*/
static bool v9fs_is_cache_enabled(struct inode *inode)
{
- struct fscache_cookie *cookie = v9fs_inode_cookie(V9FS_I(inode));
-
- return fscache_cookie_enabled(cookie) && !hlist_empty(&cookie->backing_objects);
+ return fscache_cookie_enabled(v9fs_inode_cookie(V9FS_I(inode)));
}
/**
*/
static int v9fs_begin_cache_operation(struct netfs_read_request *rreq)
{
+#ifdef CONFIG_9P_FSCACHE
struct fscache_cookie *cookie = v9fs_inode_cookie(V9FS_I(rreq->inode));
return fscache_begin_read_operation(rreq, cookie);
+#else
+ return -ENOBUFS;
+#endif
}
static const struct netfs_read_request_ops v9fs_req_ops = {
# Do not add any filesystems before this line
obj-$(CONFIG_NETFS_SUPPORT) += netfs/
-obj-$(CONFIG_FSCACHE) += fscache/
obj-$(CONFIG_REISERFS_FS) += reiserfs/
obj-$(CONFIG_EXT4_FS) += ext4/
# We place ext4 before ext2 so that clean ext3 root fs's do NOT mount using the
static bool afs_is_cache_enabled(struct inode *inode)
{
- struct fscache_cookie *cookie = afs_vnode_cache(AFS_FS_I(inode));
-
- return fscache_cookie_enabled(cookie) && !hlist_empty(&cookie->backing_objects);
+ return fscache_cookie_enabled(afs_vnode_cache(AFS_FS_I(inode)));
}
static int afs_begin_cache_operation(struct netfs_read_request *rreq)
{
+#ifdef CONFIG_AFS_FSCACHE
struct afs_vnode *vnode = AFS_FS_I(rreq->inode);
return fscache_begin_read_operation(rreq, afs_vnode_cache(vnode));
+#else
+ return -ENOBUFS;
+#endif
}
static int afs_check_write_begin(struct file *file, loff_t pos, unsigned len,
# SPDX-License-Identifier: GPL-2.0-only
-config FSCACHE
- tristate "General filesystem local caching manager"
- select NETFS_SUPPORT
- help
- This option enables a generic filesystem caching manager that can be
- used by various network and other filesystems to cache data locally.
- Different sorts of caches can be plugged in, depending on the
- resources available.
-
- See Documentation/filesystems/caching/fscache.rst for more information.
-
-config FSCACHE_STATS
- bool "Gather statistical information on local caching"
- depends on FSCACHE && PROC_FS
- select NETFS_STATS
- help
- This option causes statistical information to be gathered on local
- caching and exported through file:
-
- /proc/fs/fscache/stats
-
- The gathering of statistics adds a certain amount of overhead to
- execution as there are a quite a few stats gathered, and on a
- multi-CPU system these may be on cachelines that keep bouncing
- between CPUs. On the other hand, the stats are very useful for
- debugging purposes. Saying 'Y' here is recommended.
-
- See Documentation/filesystems/caching/fscache.rst for more information.
-
-config FSCACHE_DEBUG
- bool "Debug FS-Cache"
- depends on FSCACHE
- help
- This permits debugging to be dynamically enabled in the local caching
- management module. If this is set, the debugging output may be
- enabled by setting bits in /sys/modules/fscache/parameter/debug.
-
- See Documentation/filesystems/caching/fscache.rst for more information.
-
config FSCACHE_OLD_API
bool
+++ /dev/null
-# SPDX-License-Identifier: GPL-2.0
-#
-# Makefile for general filesystem caching code
-#
-
-fscache-y := \
- cache.o \
- cookie.o \
- fsdef.o \
- io.o \
- main.o \
- netfs.o \
- object.o \
- operation.o \
- page.o
-
-fscache-$(CONFIG_PROC_FS) += proc.o
-fscache-$(CONFIG_FSCACHE_STATS) += stats.o
-
-obj-$(CONFIG_FSCACHE) := fscache.o
+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* FS-Cache cache handling
- *
- * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- */
-
-#define FSCACHE_DEBUG_LEVEL CACHE
-#include <linux/module.h>
-#include <linux/slab.h>
-#include "internal.h"
-
-LIST_HEAD(fscache_cache_list);
-DECLARE_RWSEM(fscache_addremove_sem);
-DECLARE_WAIT_QUEUE_HEAD(fscache_cache_cleared_wq);
-EXPORT_SYMBOL(fscache_cache_cleared_wq);
-
-static LIST_HEAD(fscache_cache_tag_list);
-
-/*
- * look up a cache tag
- */
-struct fscache_cache_tag *__fscache_lookup_cache_tag(const char *name)
-{
- struct fscache_cache_tag *tag, *xtag;
-
- /* firstly check for the existence of the tag under read lock */
- down_read(&fscache_addremove_sem);
-
- list_for_each_entry(tag, &fscache_cache_tag_list, link) {
- if (strcmp(tag->name, name) == 0) {
- atomic_inc(&tag->usage);
- up_read(&fscache_addremove_sem);
- return tag;
- }
- }
-
- up_read(&fscache_addremove_sem);
-
- /* the tag does not exist - create a candidate */
- xtag = kzalloc(sizeof(*xtag) + strlen(name) + 1, GFP_KERNEL);
- if (!xtag)
- /* return a dummy tag if out of memory */
- return ERR_PTR(-ENOMEM);
-
- atomic_set(&xtag->usage, 1);
- strcpy(xtag->name, name);
-
- /* write lock, search again and add if still not present */
- down_write(&fscache_addremove_sem);
-
- list_for_each_entry(tag, &fscache_cache_tag_list, link) {
- if (strcmp(tag->name, name) == 0) {
- atomic_inc(&tag->usage);
- up_write(&fscache_addremove_sem);
- kfree(xtag);
- return tag;
- }
- }
-
- list_add_tail(&xtag->link, &fscache_cache_tag_list);
- up_write(&fscache_addremove_sem);
- return xtag;
-}
-
-/*
- * release a reference to a cache tag
- */
-void __fscache_release_cache_tag(struct fscache_cache_tag *tag)
-{
- if (tag != ERR_PTR(-ENOMEM)) {
- down_write(&fscache_addremove_sem);
-
- if (atomic_dec_and_test(&tag->usage))
- list_del_init(&tag->link);
- else
- tag = NULL;
-
- up_write(&fscache_addremove_sem);
-
- kfree(tag);
- }
-}
-
-/*
- * select a cache in which to store an object
- * - the cache addremove semaphore must be at least read-locked by the caller
- * - the object will never be an index
- */
-struct fscache_cache *fscache_select_cache_for_object(
- struct fscache_cookie *cookie)
-{
- struct fscache_cache_tag *tag;
- struct fscache_object *object;
- struct fscache_cache *cache;
-
- _enter("");
-
- if (list_empty(&fscache_cache_list)) {
- _leave(" = NULL [no cache]");
- return NULL;
- }
-
- /* we check the parent to determine the cache to use */
- spin_lock(&cookie->lock);
-
- /* the first in the parent's backing list should be the preferred
- * cache */
- if (!hlist_empty(&cookie->backing_objects)) {
- object = hlist_entry(cookie->backing_objects.first,
- struct fscache_object, cookie_link);
-
- cache = object->cache;
- if (fscache_object_is_dying(object) ||
- test_bit(FSCACHE_IOERROR, &cache->flags))
- cache = NULL;
-
- spin_unlock(&cookie->lock);
- _leave(" = %s [parent]", cache ? cache->tag->name : "NULL");
- return cache;
- }
-
- /* the parent is unbacked */
- if (cookie->type != FSCACHE_COOKIE_TYPE_INDEX) {
- /* cookie not an index and is unbacked */
- spin_unlock(&cookie->lock);
- _leave(" = NULL [cookie ub,ni]");
- return NULL;
- }
-
- spin_unlock(&cookie->lock);
-
- if (!cookie->def->select_cache)
- goto no_preference;
-
- /* ask the netfs for its preference */
- tag = cookie->def->select_cache(cookie->parent->netfs_data,
- cookie->netfs_data);
- if (!tag)
- goto no_preference;
-
- if (tag == ERR_PTR(-ENOMEM)) {
- _leave(" = NULL [nomem tag]");
- return NULL;
- }
-
- if (!tag->cache) {
- _leave(" = NULL [unbacked tag]");
- return NULL;
- }
-
- if (test_bit(FSCACHE_IOERROR, &tag->cache->flags))
- return NULL;
-
- _leave(" = %s [specific]", tag->name);
- return tag->cache;
-
-no_preference:
- /* netfs has no preference - just select first cache */
- cache = list_entry(fscache_cache_list.next,
- struct fscache_cache, link);
- _leave(" = %s [first]", cache->tag->name);
- return cache;
-}
-
-/**
- * fscache_init_cache - Initialise a cache record
- * @cache: The cache record to be initialised
- * @ops: The cache operations to be installed in that record
- * @idfmt: Format string to define identifier
- * @...: sprintf-style arguments
- *
- * Initialise a record of a cache and fill in the name.
- *
- * See Documentation/filesystems/caching/backend-api.rst for a complete
- * description.
- */
-void fscache_init_cache(struct fscache_cache *cache,
- const struct fscache_cache_ops *ops,
- const char *idfmt,
- ...)
-{
- va_list va;
-
- memset(cache, 0, sizeof(*cache));
-
- cache->ops = ops;
-
- va_start(va, idfmt);
- vsnprintf(cache->identifier, sizeof(cache->identifier), idfmt, va);
- va_end(va);
-
- INIT_WORK(&cache->op_gc, fscache_operation_gc);
- INIT_LIST_HEAD(&cache->link);
- INIT_LIST_HEAD(&cache->object_list);
- INIT_LIST_HEAD(&cache->op_gc_list);
- spin_lock_init(&cache->object_list_lock);
- spin_lock_init(&cache->op_gc_list_lock);
-}
-EXPORT_SYMBOL(fscache_init_cache);
-
-/**
- * fscache_add_cache - Declare a cache as being open for business
- * @cache: The record describing the cache
- * @ifsdef: The record of the cache object describing the top-level index
- * @tagname: The tag describing this cache
- *
- * Add a cache to the system, making it available for netfs's to use.
- *
- * See Documentation/filesystems/caching/backend-api.rst for a complete
- * description.
- */
-int fscache_add_cache(struct fscache_cache *cache,
- struct fscache_object *ifsdef,
- const char *tagname)
-{
- struct fscache_cache_tag *tag;
-
- ASSERTCMP(ifsdef->cookie, ==, &fscache_fsdef_index);
- BUG_ON(!cache->ops);
- BUG_ON(!ifsdef);
-
- cache->flags = 0;
- ifsdef->event_mask =
- ((1 << NR_FSCACHE_OBJECT_EVENTS) - 1) &
- ~(1 << FSCACHE_OBJECT_EV_CLEARED);
- __set_bit(FSCACHE_OBJECT_IS_AVAILABLE, &ifsdef->flags);
-
- if (!tagname)
- tagname = cache->identifier;
-
- BUG_ON(!tagname[0]);
-
- _enter("{%s.%s},,%s", cache->ops->name, cache->identifier, tagname);
-
- /* we use the cache tag to uniquely identify caches */
- tag = __fscache_lookup_cache_tag(tagname);
- if (IS_ERR(tag))
- goto nomem;
-
- if (test_and_set_bit(FSCACHE_TAG_RESERVED, &tag->flags))
- goto tag_in_use;
-
- cache->kobj = kobject_create_and_add(tagname, fscache_root);
- if (!cache->kobj)
- goto error;
-
- ifsdef->cache = cache;
- cache->fsdef = ifsdef;
-
- down_write(&fscache_addremove_sem);
-
- tag->cache = cache;
- cache->tag = tag;
-
- /* add the cache to the list */
- list_add(&cache->link, &fscache_cache_list);
-
- /* add the cache's netfs definition index object to the cache's
- * list */
- spin_lock(&cache->object_list_lock);
- list_add_tail(&ifsdef->cache_link, &cache->object_list);
- spin_unlock(&cache->object_list_lock);
-
- /* add the cache's netfs definition index object to the top level index
- * cookie as a known backing object */
- spin_lock(&fscache_fsdef_index.lock);
-
- hlist_add_head(&ifsdef->cookie_link,
- &fscache_fsdef_index.backing_objects);
-
- refcount_inc(&fscache_fsdef_index.ref);
-
- /* done */
- spin_unlock(&fscache_fsdef_index.lock);
- up_write(&fscache_addremove_sem);
-
- pr_notice("Cache \"%s\" added (type %s)\n",
- cache->tag->name, cache->ops->name);
- kobject_uevent(cache->kobj, KOBJ_ADD);
-
- _leave(" = 0 [%s]", cache->identifier);
- return 0;
-
-tag_in_use:
- pr_err("Cache tag '%s' already in use\n", tagname);
- __fscache_release_cache_tag(tag);
- _leave(" = -EXIST");
- return -EEXIST;
-
-error:
- __fscache_release_cache_tag(tag);
- _leave(" = -EINVAL");
- return -EINVAL;
-
-nomem:
- _leave(" = -ENOMEM");
- return -ENOMEM;
-}
-EXPORT_SYMBOL(fscache_add_cache);
-
-/**
- * fscache_io_error - Note a cache I/O error
- * @cache: The record describing the cache
- *
- * Note that an I/O error occurred in a cache and that it should no longer be
- * used for anything. This also reports the error into the kernel log.
- *
- * See Documentation/filesystems/caching/backend-api.rst for a complete
- * description.
- */
-void fscache_io_error(struct fscache_cache *cache)
-{
- if (!test_and_set_bit(FSCACHE_IOERROR, &cache->flags))
- pr_err("Cache '%s' stopped due to I/O error\n",
- cache->ops->name);
-}
-EXPORT_SYMBOL(fscache_io_error);
-
-/*
- * request withdrawal of all the objects in a cache
- * - all the objects being withdrawn are moved onto the supplied list
- */
-static void fscache_withdraw_all_objects(struct fscache_cache *cache,
- struct list_head *dying_objects)
-{
- struct fscache_object *object;
-
- while (!list_empty(&cache->object_list)) {
- spin_lock(&cache->object_list_lock);
-
- if (!list_empty(&cache->object_list)) {
- object = list_entry(cache->object_list.next,
- struct fscache_object, cache_link);
- list_move_tail(&object->cache_link, dying_objects);
-
- _debug("withdraw %x", object->cookie->debug_id);
-
- /* This must be done under object_list_lock to prevent
- * a race with fscache_drop_object().
- */
- fscache_raise_event(object, FSCACHE_OBJECT_EV_KILL);
- }
-
- spin_unlock(&cache->object_list_lock);
- cond_resched();
- }
-}
-
-/**
- * fscache_withdraw_cache - Withdraw a cache from the active service
- * @cache: The record describing the cache
- *
- * Withdraw a cache from service, unbinding all its cache objects from the
- * netfs cookies they're currently representing.
- *
- * See Documentation/filesystems/caching/backend-api.rst for a complete
- * description.
- */
-void fscache_withdraw_cache(struct fscache_cache *cache)
-{
- LIST_HEAD(dying_objects);
-
- _enter("");
-
- pr_notice("Withdrawing cache \"%s\"\n",
- cache->tag->name);
-
- /* make the cache unavailable for cookie acquisition */
- if (test_and_set_bit(FSCACHE_CACHE_WITHDRAWN, &cache->flags))
- BUG();
-
- down_write(&fscache_addremove_sem);
- list_del_init(&cache->link);
- cache->tag->cache = NULL;
- up_write(&fscache_addremove_sem);
-
- /* make sure all pages pinned by operations on behalf of the netfs are
- * written to disk */
- fscache_stat(&fscache_n_cop_sync_cache);
- cache->ops->sync_cache(cache);
- fscache_stat_d(&fscache_n_cop_sync_cache);
-
- /* dissociate all the netfs pages backed by this cache from the block
- * mappings in the cache */
- fscache_stat(&fscache_n_cop_dissociate_pages);
- cache->ops->dissociate_pages(cache);
- fscache_stat_d(&fscache_n_cop_dissociate_pages);
-
- /* we now have to destroy all the active objects pertaining to this
- * cache - which we do by passing them off to thread pool to be
- * disposed of */
- _debug("destroy");
-
- fscache_withdraw_all_objects(cache, &dying_objects);
-
- /* wait for all extant objects to finish their outstanding operations
- * and go away */
- _debug("wait for finish");
- wait_event(fscache_cache_cleared_wq,
- atomic_read(&cache->object_count) == 0);
- _debug("wait for clearance");
- wait_event(fscache_cache_cleared_wq,
- list_empty(&cache->object_list));
- _debug("cleared");
- ASSERT(list_empty(&dying_objects));
-
- kobject_put(cache->kobj);
-
- clear_bit(FSCACHE_TAG_RESERVED, &cache->tag->flags);
- fscache_release_cache_tag(cache->tag);
- cache->tag = NULL;
-
- _leave("");
-}
-EXPORT_SYMBOL(fscache_withdraw_cache);
+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* netfs cookie management
- *
- * Copyright (C) 2004-2007 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- *
- * See Documentation/filesystems/caching/netfs-api.rst for more information on
- * the netfs API.
- */
-
-#define FSCACHE_DEBUG_LEVEL COOKIE
-#include <linux/module.h>
-#include <linux/slab.h>
-#include "internal.h"
-
-struct kmem_cache *fscache_cookie_jar;
-
-static atomic_t fscache_object_debug_id = ATOMIC_INIT(0);
-
-#define fscache_cookie_hash_shift 15
-static struct hlist_bl_head fscache_cookie_hash[1 << fscache_cookie_hash_shift];
-static LIST_HEAD(fscache_cookies);
-static DEFINE_RWLOCK(fscache_cookies_lock);
-
-static int fscache_acquire_non_index_cookie(struct fscache_cookie *cookie,
- loff_t object_size);
-static int fscache_alloc_object(struct fscache_cache *cache,
- struct fscache_cookie *cookie);
-static int fscache_attach_object(struct fscache_cookie *cookie,
- struct fscache_object *object);
-
-static void fscache_print_cookie(struct fscache_cookie *cookie, char prefix)
-{
- struct fscache_object *object;
- struct hlist_node *o;
- const u8 *k;
- unsigned loop;
-
- pr_err("%c-cookie c=%08x [p=%08x fl=%lx nc=%u na=%u]\n",
- prefix,
- cookie->debug_id,
- cookie->parent ? cookie->parent->debug_id : 0,
- cookie->flags,
- atomic_read(&cookie->n_children),
- atomic_read(&cookie->n_active));
- pr_err("%c-cookie d=%p{%s} n=%p\n",
- prefix,
- cookie->def,
- cookie->def ? cookie->def->name : "?",
- cookie->netfs_data);
-
- o = READ_ONCE(cookie->backing_objects.first);
- if (o) {
- object = hlist_entry(o, struct fscache_object, cookie_link);
- pr_err("%c-cookie o=%u\n", prefix, object->debug_id);
- }
-
- pr_err("%c-key=[%u] '", prefix, cookie->key_len);
- k = (cookie->key_len <= sizeof(cookie->inline_key)) ?
- cookie->inline_key : cookie->key;
- for (loop = 0; loop < cookie->key_len; loop++)
- pr_cont("%02x", k[loop]);
- pr_cont("'\n");
-}
-
-void fscache_free_cookie(struct fscache_cookie *cookie)
-{
- if (cookie) {
- BUG_ON(!hlist_empty(&cookie->backing_objects));
- write_lock(&fscache_cookies_lock);
- list_del(&cookie->proc_link);
- write_unlock(&fscache_cookies_lock);
- if (cookie->aux_len > sizeof(cookie->inline_aux))
- kfree(cookie->aux);
- if (cookie->key_len > sizeof(cookie->inline_key))
- kfree(cookie->key);
- kmem_cache_free(fscache_cookie_jar, cookie);
- }
-}
-
-/*
- * Set the index key in a cookie. The cookie struct has space for a 16-byte
- * key plus length and hash, but if that's not big enough, it's instead a
- * pointer to a buffer containing 3 bytes of hash, 1 byte of length and then
- * the key data.
- */
-static int fscache_set_key(struct fscache_cookie *cookie,
- const void *index_key, size_t index_key_len)
-{
- u32 *buf;
- int bufs;
-
- bufs = DIV_ROUND_UP(index_key_len, sizeof(*buf));
-
- if (index_key_len > sizeof(cookie->inline_key)) {
- buf = kcalloc(bufs, sizeof(*buf), GFP_KERNEL);
- if (!buf)
- return -ENOMEM;
- cookie->key = buf;
- } else {
- buf = (u32 *)cookie->inline_key;
- }
-
- memcpy(buf, index_key, index_key_len);
- cookie->key_hash = fscache_hash(0, buf, bufs);
- return 0;
-}
-
-static long fscache_compare_cookie(const struct fscache_cookie *a,
- const struct fscache_cookie *b)
-{
- const void *ka, *kb;
-
- if (a->key_hash != b->key_hash)
- return (long)a->key_hash - (long)b->key_hash;
- if (a->parent != b->parent)
- return (long)a->parent - (long)b->parent;
- if (a->key_len != b->key_len)
- return (long)a->key_len - (long)b->key_len;
- if (a->type != b->type)
- return (long)a->type - (long)b->type;
-
- if (a->key_len <= sizeof(a->inline_key)) {
- ka = &a->inline_key;
- kb = &b->inline_key;
- } else {
- ka = a->key;
- kb = b->key;
- }
- return memcmp(ka, kb, a->key_len);
-}
-
-static atomic_t fscache_cookie_debug_id = ATOMIC_INIT(1);
-
-/*
- * Allocate a cookie.
- */
-struct fscache_cookie *fscache_alloc_cookie(
- struct fscache_cookie *parent,
- const struct fscache_cookie_def *def,
- const void *index_key, size_t index_key_len,
- const void *aux_data, size_t aux_data_len,
- void *netfs_data,
- loff_t object_size)
-{
- struct fscache_cookie *cookie;
-
- /* allocate and initialise a cookie */
- cookie = kmem_cache_zalloc(fscache_cookie_jar, GFP_KERNEL);
- if (!cookie)
- return NULL;
-
- cookie->key_len = index_key_len;
- cookie->aux_len = aux_data_len;
-
- if (fscache_set_key(cookie, index_key, index_key_len) < 0)
- goto nomem;
-
- if (cookie->aux_len <= sizeof(cookie->inline_aux)) {
- memcpy(cookie->inline_aux, aux_data, cookie->aux_len);
- } else {
- cookie->aux = kmemdup(aux_data, cookie->aux_len, GFP_KERNEL);
- if (!cookie->aux)
- goto nomem;
- }
-
- refcount_set(&cookie->ref, 1);
- atomic_set(&cookie->n_children, 0);
- cookie->debug_id = atomic_inc_return(&fscache_cookie_debug_id);
-
- /* We keep the active count elevated until relinquishment to prevent an
- * attempt to wake up every time the object operations queue quiesces.
- */
- atomic_set(&cookie->n_active, 1);
-
- cookie->def = def;
- cookie->parent = parent;
- cookie->netfs_data = netfs_data;
- cookie->flags = (1 << FSCACHE_COOKIE_NO_DATA_YET);
- cookie->type = def->type;
- spin_lock_init(&cookie->lock);
- spin_lock_init(&cookie->stores_lock);
- INIT_HLIST_HEAD(&cookie->backing_objects);
-
- /* radix tree insertion won't use the preallocation pool unless it's
- * told it may not wait */
- INIT_RADIX_TREE(&cookie->stores, GFP_NOFS & ~__GFP_DIRECT_RECLAIM);
-
- write_lock(&fscache_cookies_lock);
- list_add_tail(&cookie->proc_link, &fscache_cookies);
- write_unlock(&fscache_cookies_lock);
- return cookie;
-
-nomem:
- fscache_free_cookie(cookie);
- return NULL;
-}
-
-/*
- * Attempt to insert the new cookie into the hash. If there's a collision, we
- * return the old cookie if it's not in use and an error otherwise.
- */
-struct fscache_cookie *fscache_hash_cookie(struct fscache_cookie *candidate)
-{
- struct fscache_cookie *cursor;
- struct hlist_bl_head *h;
- struct hlist_bl_node *p;
- unsigned int bucket;
-
- bucket = candidate->key_hash & (ARRAY_SIZE(fscache_cookie_hash) - 1);
- h = &fscache_cookie_hash[bucket];
-
- hlist_bl_lock(h);
- hlist_bl_for_each_entry(cursor, p, h, hash_link) {
- if (fscache_compare_cookie(candidate, cursor) == 0)
- goto collision;
- }
-
- __set_bit(FSCACHE_COOKIE_ACQUIRED, &candidate->flags);
- fscache_cookie_get(candidate->parent, fscache_cookie_get_acquire_parent);
- atomic_inc(&candidate->parent->n_children);
- hlist_bl_add_head(&candidate->hash_link, h);
- hlist_bl_unlock(h);
- return candidate;
-
-collision:
- if (test_and_set_bit(FSCACHE_COOKIE_ACQUIRED, &cursor->flags)) {
- trace_fscache_cookie(cursor->debug_id, refcount_read(&cursor->ref),
- fscache_cookie_collision);
- pr_err("Duplicate cookie detected\n");
- fscache_print_cookie(cursor, 'O');
- fscache_print_cookie(candidate, 'N');
- hlist_bl_unlock(h);
- return NULL;
- }
-
- fscache_cookie_get(cursor, fscache_cookie_get_reacquire);
- hlist_bl_unlock(h);
- return cursor;
-}
-
-/*
- * request a cookie to represent an object (index, datafile, xattr, etc)
- * - parent specifies the parent object
- * - the top level index cookie for each netfs is stored in the fscache_netfs
- * struct upon registration
- * - def points to the definition
- * - the netfs_data will be passed to the functions pointed to in *def
- * - all attached caches will be searched to see if they contain this object
- * - index objects aren't stored on disk until there's a dependent file that
- * needs storing
- * - other objects are stored in a selected cache immediately, and all the
- * indices forming the path to it are instantiated if necessary
- * - we never let on to the netfs about errors
- * - we may set a negative cookie pointer, but that's okay
- */
-struct fscache_cookie *__fscache_acquire_cookie(
- struct fscache_cookie *parent,
- const struct fscache_cookie_def *def,
- const void *index_key, size_t index_key_len,
- const void *aux_data, size_t aux_data_len,
- void *netfs_data,
- loff_t object_size,
- bool enable)
-{
- struct fscache_cookie *candidate, *cookie;
-
- BUG_ON(!def);
-
- _enter("{%s},{%s},%p,%u",
- parent ? (char *) parent->def->name : "<no-parent>",
- def->name, netfs_data, enable);
-
- if (!index_key || !index_key_len || index_key_len > 255 || aux_data_len > 255)
- return NULL;
- if (!aux_data || !aux_data_len) {
- aux_data = NULL;
- aux_data_len = 0;
- }
-
- fscache_stat(&fscache_n_acquires);
-
- /* if there's no parent cookie, then we don't create one here either */
- if (!parent) {
- fscache_stat(&fscache_n_acquires_null);
- _leave(" [no parent]");
- return NULL;
- }
-
- /* validate the definition */
- BUG_ON(!def->name[0]);
-
- BUG_ON(def->type == FSCACHE_COOKIE_TYPE_INDEX &&
- parent->type != FSCACHE_COOKIE_TYPE_INDEX);
-
- candidate = fscache_alloc_cookie(parent, def,
- index_key, index_key_len,
- aux_data, aux_data_len,
- netfs_data, object_size);
- if (!candidate) {
- fscache_stat(&fscache_n_acquires_oom);
- _leave(" [ENOMEM]");
- return NULL;
- }
-
- cookie = fscache_hash_cookie(candidate);
- if (!cookie) {
- trace_fscache_cookie(candidate->debug_id, 1,
- fscache_cookie_discard);
- goto out;
- }
-
- if (cookie == candidate)
- candidate = NULL;
-
- switch (cookie->type) {
- case FSCACHE_COOKIE_TYPE_INDEX:
- fscache_stat(&fscache_n_cookie_index);
- break;
- case FSCACHE_COOKIE_TYPE_DATAFILE:
- fscache_stat(&fscache_n_cookie_data);
- break;
- default:
- fscache_stat(&fscache_n_cookie_special);
- break;
- }
-
- trace_fscache_acquire(cookie);
-
- if (enable) {
- /* if the object is an index then we need do nothing more here
- * - we create indices on disk when we need them as an index
- * may exist in multiple caches */
- if (cookie->type != FSCACHE_COOKIE_TYPE_INDEX) {
- if (fscache_acquire_non_index_cookie(cookie, object_size) == 0) {
- set_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags);
- } else {
- atomic_dec(&parent->n_children);
- fscache_cookie_put(cookie,
- fscache_cookie_put_acquire_nobufs);
- fscache_stat(&fscache_n_acquires_nobufs);
- _leave(" = NULL");
- return NULL;
- }
- } else {
- set_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags);
- }
- }
-
- fscache_stat(&fscache_n_acquires_ok);
-
-out:
- fscache_free_cookie(candidate);
- return cookie;
-}
-EXPORT_SYMBOL(__fscache_acquire_cookie);
-
-/*
- * Enable a cookie to permit it to accept new operations.
- */
-void __fscache_enable_cookie(struct fscache_cookie *cookie,
- const void *aux_data,
- loff_t object_size,
- bool (*can_enable)(void *data),
- void *data)
-{
- _enter("%x", cookie->debug_id);
-
- trace_fscache_enable(cookie);
-
- wait_on_bit_lock(&cookie->flags, FSCACHE_COOKIE_ENABLEMENT_LOCK,
- TASK_UNINTERRUPTIBLE);
-
- fscache_update_aux(cookie, aux_data);
-
- if (test_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags))
- goto out_unlock;
-
- if (can_enable && !can_enable(data)) {
- /* The netfs decided it didn't want to enable after all */
- } else if (cookie->type != FSCACHE_COOKIE_TYPE_INDEX) {
- /* Wait for outstanding disablement to complete */
- __fscache_wait_on_invalidate(cookie);
-
- if (fscache_acquire_non_index_cookie(cookie, object_size) == 0)
- set_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags);
- } else {
- set_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags);
- }
-
-out_unlock:
- clear_bit_unlock(FSCACHE_COOKIE_ENABLEMENT_LOCK, &cookie->flags);
- wake_up_bit(&cookie->flags, FSCACHE_COOKIE_ENABLEMENT_LOCK);
-}
-EXPORT_SYMBOL(__fscache_enable_cookie);
-
-/*
- * acquire a non-index cookie
- * - this must make sure the index chain is instantiated and instantiate the
- * object representation too
- */
-static int fscache_acquire_non_index_cookie(struct fscache_cookie *cookie,
- loff_t object_size)
-{
- struct fscache_object *object;
- struct fscache_cache *cache;
- int ret;
-
- _enter("");
-
- set_bit(FSCACHE_COOKIE_UNAVAILABLE, &cookie->flags);
-
- /* now we need to see whether the backing objects for this cookie yet
- * exist, if not there'll be nothing to search */
- down_read(&fscache_addremove_sem);
-
- if (list_empty(&fscache_cache_list)) {
- up_read(&fscache_addremove_sem);
- _leave(" = 0 [no caches]");
- return 0;
- }
-
- /* select a cache in which to store the object */
- cache = fscache_select_cache_for_object(cookie->parent);
- if (!cache) {
- up_read(&fscache_addremove_sem);
- fscache_stat(&fscache_n_acquires_no_cache);
- _leave(" = -ENOMEDIUM [no cache]");
- return -ENOMEDIUM;
- }
-
- _debug("cache %s", cache->tag->name);
-
- set_bit(FSCACHE_COOKIE_LOOKING_UP, &cookie->flags);
-
- /* ask the cache to allocate objects for this cookie and its parent
- * chain */
- ret = fscache_alloc_object(cache, cookie);
- if (ret < 0) {
- up_read(&fscache_addremove_sem);
- _leave(" = %d", ret);
- return ret;
- }
-
- spin_lock(&cookie->lock);
- if (hlist_empty(&cookie->backing_objects)) {
- spin_unlock(&cookie->lock);
- goto unavailable;
- }
-
- object = hlist_entry(cookie->backing_objects.first,
- struct fscache_object, cookie_link);
-
- fscache_set_store_limit(object, object_size);
-
- /* initiate the process of looking up all the objects in the chain
- * (done by fscache_initialise_object()) */
- fscache_raise_event(object, FSCACHE_OBJECT_EV_NEW_CHILD);
-
- spin_unlock(&cookie->lock);
-
- /* we may be required to wait for lookup to complete at this point */
- if (!fscache_defer_lookup) {
- wait_on_bit(&cookie->flags, FSCACHE_COOKIE_LOOKING_UP,
- TASK_UNINTERRUPTIBLE);
- if (test_bit(FSCACHE_COOKIE_UNAVAILABLE, &cookie->flags))
- goto unavailable;
- }
-
- up_read(&fscache_addremove_sem);
- _leave(" = 0 [deferred]");
- return 0;
-
-unavailable:
- up_read(&fscache_addremove_sem);
- _leave(" = -ENOBUFS");
- return -ENOBUFS;
-}
-
-/*
- * recursively allocate cache object records for a cookie/cache combination
- * - caller must be holding the addremove sem
- */
-static int fscache_alloc_object(struct fscache_cache *cache,
- struct fscache_cookie *cookie)
-{
- struct fscache_object *object;
- int ret;
-
- _enter("%s,%x{%s}", cache->tag->name, cookie->debug_id, cookie->def->name);
-
- spin_lock(&cookie->lock);
- hlist_for_each_entry(object, &cookie->backing_objects,
- cookie_link) {
- if (object->cache == cache)
- goto object_already_extant;
- }
- spin_unlock(&cookie->lock);
-
- /* ask the cache to allocate an object (we may end up with duplicate
- * objects at this stage, but we sort that out later) */
- fscache_stat(&fscache_n_cop_alloc_object);
- object = cache->ops->alloc_object(cache, cookie);
- fscache_stat_d(&fscache_n_cop_alloc_object);
- if (IS_ERR(object)) {
- fscache_stat(&fscache_n_object_no_alloc);
- ret = PTR_ERR(object);
- goto error;
- }
-
- ASSERTCMP(object->cookie, ==, cookie);
- fscache_stat(&fscache_n_object_alloc);
-
- object->debug_id = atomic_inc_return(&fscache_object_debug_id);
-
- _debug("ALLOC OBJ%x: %s {%lx}",
- object->debug_id, cookie->def->name, object->events);
-
- ret = fscache_alloc_object(cache, cookie->parent);
- if (ret < 0)
- goto error_put;
-
- /* only attach if we managed to allocate all we needed, otherwise
- * discard the object we just allocated and instead use the one
- * attached to the cookie */
- if (fscache_attach_object(cookie, object) < 0) {
- fscache_stat(&fscache_n_cop_put_object);
- cache->ops->put_object(object, fscache_obj_put_attach_fail);
- fscache_stat_d(&fscache_n_cop_put_object);
- }
-
- _leave(" = 0");
- return 0;
-
-object_already_extant:
- ret = -ENOBUFS;
- if (fscache_object_is_dying(object) ||
- fscache_cache_is_broken(object)) {
- spin_unlock(&cookie->lock);
- goto error;
- }
- spin_unlock(&cookie->lock);
- _leave(" = 0 [found]");
- return 0;
-
-error_put:
- fscache_stat(&fscache_n_cop_put_object);
- cache->ops->put_object(object, fscache_obj_put_alloc_fail);
- fscache_stat_d(&fscache_n_cop_put_object);
-error:
- _leave(" = %d", ret);
- return ret;
-}
-
-/*
- * attach a cache object to a cookie
- */
-static int fscache_attach_object(struct fscache_cookie *cookie,
- struct fscache_object *object)
-{
- struct fscache_object *p;
- struct fscache_cache *cache = object->cache;
- int ret;
-
- _enter("{%s},{OBJ%x}", cookie->def->name, object->debug_id);
-
- ASSERTCMP(object->cookie, ==, cookie);
-
- spin_lock(&cookie->lock);
-
- /* there may be multiple initial creations of this object, but we only
- * want one */
- ret = -EEXIST;
- hlist_for_each_entry(p, &cookie->backing_objects, cookie_link) {
- if (p->cache == object->cache) {
- if (fscache_object_is_dying(p))
- ret = -ENOBUFS;
- goto cant_attach_object;
- }
- }
-
- /* pin the parent object */
- spin_lock_nested(&cookie->parent->lock, 1);
- hlist_for_each_entry(p, &cookie->parent->backing_objects,
- cookie_link) {
- if (p->cache == object->cache) {
- if (fscache_object_is_dying(p)) {
- ret = -ENOBUFS;
- spin_unlock(&cookie->parent->lock);
- goto cant_attach_object;
- }
- object->parent = p;
- spin_lock(&p->lock);
- p->n_children++;
- spin_unlock(&p->lock);
- break;
- }
- }
- spin_unlock(&cookie->parent->lock);
-
- /* attach to the cache's object list */
- if (list_empty(&object->cache_link)) {
- spin_lock(&cache->object_list_lock);
- list_add(&object->cache_link, &cache->object_list);
- spin_unlock(&cache->object_list_lock);
- }
-
- /* Attach to the cookie. The object already has a ref on it. */
- hlist_add_head(&object->cookie_link, &cookie->backing_objects);
- ret = 0;
-
-cant_attach_object:
- spin_unlock(&cookie->lock);
- _leave(" = %d", ret);
- return ret;
-}
-
-/*
- * Invalidate an object. Callable with spinlocks held.
- */
-void __fscache_invalidate(struct fscache_cookie *cookie)
-{
- struct fscache_object *object;
-
- _enter("{%s}", cookie->def->name);
-
- fscache_stat(&fscache_n_invalidates);
-
- /* Only permit invalidation of data files. Invalidating an index will
- * require the caller to release all its attachments to the tree rooted
- * there, and if it's doing that, it may as well just retire the
- * cookie.
- */
- ASSERTCMP(cookie->type, ==, FSCACHE_COOKIE_TYPE_DATAFILE);
-
- /* If there's an object, we tell the object state machine to handle the
- * invalidation on our behalf, otherwise there's nothing to do.
- */
- if (!hlist_empty(&cookie->backing_objects)) {
- spin_lock(&cookie->lock);
-
- if (fscache_cookie_enabled(cookie) &&
- !hlist_empty(&cookie->backing_objects) &&
- !test_and_set_bit(FSCACHE_COOKIE_INVALIDATING,
- &cookie->flags)) {
- object = hlist_entry(cookie->backing_objects.first,
- struct fscache_object,
- cookie_link);
- if (fscache_object_is_live(object))
- fscache_raise_event(
- object, FSCACHE_OBJECT_EV_INVALIDATE);
- }
-
- spin_unlock(&cookie->lock);
- }
-
- _leave("");
-}
-EXPORT_SYMBOL(__fscache_invalidate);
-
-/*
- * Wait for object invalidation to complete.
- */
-void __fscache_wait_on_invalidate(struct fscache_cookie *cookie)
-{
- _enter("%x", cookie->debug_id);
-
- wait_on_bit(&cookie->flags, FSCACHE_COOKIE_INVALIDATING,
- TASK_UNINTERRUPTIBLE);
-
- _leave("");
-}
-EXPORT_SYMBOL(__fscache_wait_on_invalidate);
-
-/*
- * update the index entries backing a cookie
- */
-void __fscache_update_cookie(struct fscache_cookie *cookie, const void *aux_data)
-{
- struct fscache_object *object;
-
- fscache_stat(&fscache_n_updates);
-
- if (!cookie) {
- fscache_stat(&fscache_n_updates_null);
- _leave(" [no cookie]");
- return;
- }
-
- _enter("{%s}", cookie->def->name);
-
- spin_lock(&cookie->lock);
-
- fscache_update_aux(cookie, aux_data);
-
- if (fscache_cookie_enabled(cookie)) {
- /* update the index entry on disk in each cache backing this
- * cookie.
- */
- hlist_for_each_entry(object,
- &cookie->backing_objects, cookie_link) {
- fscache_raise_event(object, FSCACHE_OBJECT_EV_UPDATE);
- }
- }
-
- spin_unlock(&cookie->lock);
- _leave("");
-}
-EXPORT_SYMBOL(__fscache_update_cookie);
-
-/*
- * Disable a cookie to stop it from accepting new requests from the netfs.
- */
-void __fscache_disable_cookie(struct fscache_cookie *cookie,
- const void *aux_data,
- bool invalidate)
-{
- struct fscache_object *object;
- bool awaken = false;
-
- _enter("%x,%u", cookie->debug_id, invalidate);
-
- trace_fscache_disable(cookie);
-
- ASSERTCMP(atomic_read(&cookie->n_active), >, 0);
-
- if (atomic_read(&cookie->n_children) != 0) {
- pr_err("Cookie '%s' still has children\n",
- cookie->def->name);
- BUG();
- }
-
- wait_on_bit_lock(&cookie->flags, FSCACHE_COOKIE_ENABLEMENT_LOCK,
- TASK_UNINTERRUPTIBLE);
-
- fscache_update_aux(cookie, aux_data);
-
- if (!test_and_clear_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags))
- goto out_unlock_enable;
-
- /* If the cookie is being invalidated, wait for that to complete first
- * so that we can reuse the flag.
- */
- __fscache_wait_on_invalidate(cookie);
-
- /* Dispose of the backing objects */
- set_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags);
-
- spin_lock(&cookie->lock);
- if (!hlist_empty(&cookie->backing_objects)) {
- hlist_for_each_entry(object, &cookie->backing_objects, cookie_link) {
- if (invalidate)
- set_bit(FSCACHE_OBJECT_RETIRED, &object->flags);
- clear_bit(FSCACHE_OBJECT_PENDING_WRITE, &object->flags);
- fscache_raise_event(object, FSCACHE_OBJECT_EV_KILL);
- }
- } else {
- if (test_and_clear_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags))
- awaken = true;
- }
- spin_unlock(&cookie->lock);
- if (awaken)
- wake_up_bit(&cookie->flags, FSCACHE_COOKIE_INVALIDATING);
-
- /* Wait for cessation of activity requiring access to the netfs (when
- * n_active reaches 0). This makes sure outstanding reads and writes
- * have completed.
- */
- if (!atomic_dec_and_test(&cookie->n_active)) {
- wait_var_event(&cookie->n_active,
- !atomic_read(&cookie->n_active));
- }
-
- /* Make sure any pending writes are cancelled. */
- if (cookie->type != FSCACHE_COOKIE_TYPE_INDEX)
- fscache_invalidate_writes(cookie);
-
- /* Reset the cookie state if it wasn't relinquished */
- if (!test_bit(FSCACHE_COOKIE_RELINQUISHED, &cookie->flags)) {
- atomic_inc(&cookie->n_active);
- set_bit(FSCACHE_COOKIE_NO_DATA_YET, &cookie->flags);
- }
-
-out_unlock_enable:
- clear_bit_unlock(FSCACHE_COOKIE_ENABLEMENT_LOCK, &cookie->flags);
- wake_up_bit(&cookie->flags, FSCACHE_COOKIE_ENABLEMENT_LOCK);
- _leave("");
-}
-EXPORT_SYMBOL(__fscache_disable_cookie);
-
-/*
- * release a cookie back to the cache
- * - the object will be marked as recyclable on disk if retire is true
- * - all dependents of this cookie must have already been unregistered
- * (indices/files/pages)
- */
-void __fscache_relinquish_cookie(struct fscache_cookie *cookie,
- const void *aux_data,
- bool retire)
-{
- fscache_stat(&fscache_n_relinquishes);
- if (retire)
- fscache_stat(&fscache_n_relinquishes_retire);
-
- if (!cookie) {
- fscache_stat(&fscache_n_relinquishes_null);
- _leave(" [no cookie]");
- return;
- }
-
- _enter("%x{%s,%d},%d",
- cookie->debug_id, cookie->def->name,
- atomic_read(&cookie->n_active), retire);
-
- trace_fscache_relinquish(cookie, retire);
-
- /* No further netfs-accessing operations on this cookie permitted */
- if (test_and_set_bit(FSCACHE_COOKIE_RELINQUISHED, &cookie->flags))
- BUG();
-
- __fscache_disable_cookie(cookie, aux_data, retire);
-
- /* Clear pointers back to the netfs */
- cookie->netfs_data = NULL;
- cookie->def = NULL;
- BUG_ON(!radix_tree_empty(&cookie->stores));
-
- if (cookie->parent) {
- ASSERTCMP(refcount_read(&cookie->parent->ref), >, 0);
- ASSERTCMP(atomic_read(&cookie->parent->n_children), >, 0);
- atomic_dec(&cookie->parent->n_children);
- }
-
- /* Dispose of the netfs's link to the cookie */
- fscache_cookie_put(cookie, fscache_cookie_put_relinquish);
-
- _leave("");
-}
-EXPORT_SYMBOL(__fscache_relinquish_cookie);
-
-/*
- * Remove a cookie from the hash table.
- */
-static void fscache_unhash_cookie(struct fscache_cookie *cookie)
-{
- struct hlist_bl_head *h;
- unsigned int bucket;
-
- bucket = cookie->key_hash & (ARRAY_SIZE(fscache_cookie_hash) - 1);
- h = &fscache_cookie_hash[bucket];
-
- hlist_bl_lock(h);
- hlist_bl_del(&cookie->hash_link);
- hlist_bl_unlock(h);
-}
-
-/*
- * Drop a reference to a cookie.
- */
-void fscache_cookie_put(struct fscache_cookie *cookie,
- enum fscache_cookie_trace where)
-{
- struct fscache_cookie *parent;
- int ref;
-
- _enter("%x", cookie->debug_id);
-
- do {
- unsigned int cookie_debug_id = cookie->debug_id;
- bool zero = __refcount_dec_and_test(&cookie->ref, &ref);
-
- trace_fscache_cookie(cookie_debug_id, ref - 1, where);
- if (!zero)
- return;
-
- parent = cookie->parent;
- fscache_unhash_cookie(cookie);
- fscache_free_cookie(cookie);
-
- cookie = parent;
- where = fscache_cookie_put_parent;
- } while (cookie);
-
- _leave("");
-}
-
-/*
- * Get a reference to a cookie.
- */
-struct fscache_cookie *fscache_cookie_get(struct fscache_cookie *cookie,
- enum fscache_cookie_trace where)
-{
- int ref;
-
- __refcount_inc(&cookie->ref, &ref);
- trace_fscache_cookie(cookie->debug_id, ref + 1, where);
- return cookie;
-}
-
-/*
- * check the consistency between the netfs inode and the backing cache
- *
- * NOTE: it only serves no-index type
- */
-int __fscache_check_consistency(struct fscache_cookie *cookie,
- const void *aux_data)
-{
- struct fscache_operation *op;
- struct fscache_object *object;
- bool wake_cookie = false;
- int ret;
-
- _enter("%p,", cookie);
-
- ASSERTCMP(cookie->type, ==, FSCACHE_COOKIE_TYPE_DATAFILE);
-
- if (fscache_wait_for_deferred_lookup(cookie) < 0)
- return -ERESTARTSYS;
-
- if (hlist_empty(&cookie->backing_objects))
- return 0;
-
- op = kzalloc(sizeof(*op), GFP_NOIO | __GFP_NOMEMALLOC | __GFP_NORETRY);
- if (!op)
- return -ENOMEM;
-
- fscache_operation_init(cookie, op, NULL, NULL, NULL);
- op->flags = FSCACHE_OP_MYTHREAD |
- (1 << FSCACHE_OP_WAITING) |
- (1 << FSCACHE_OP_UNUSE_COOKIE);
- trace_fscache_page_op(cookie, NULL, op, fscache_page_op_check_consistency);
-
- spin_lock(&cookie->lock);
-
- fscache_update_aux(cookie, aux_data);
-
- if (!fscache_cookie_enabled(cookie) ||
- hlist_empty(&cookie->backing_objects))
- goto inconsistent;
- object = hlist_entry(cookie->backing_objects.first,
- struct fscache_object, cookie_link);
- if (test_bit(FSCACHE_IOERROR, &object->cache->flags))
- goto inconsistent;
-
- op->debug_id = atomic_inc_return(&fscache_op_debug_id);
-
- __fscache_use_cookie(cookie);
- if (fscache_submit_op(object, op) < 0)
- goto submit_failed;
-
- /* the work queue now carries its own ref on the object */
- spin_unlock(&cookie->lock);
-
- ret = fscache_wait_for_operation_activation(object, op, NULL, NULL);
- if (ret == 0) {
- /* ask the cache to honour the operation */
- ret = object->cache->ops->check_consistency(op);
- fscache_op_complete(op, false);
- } else if (ret == -ENOBUFS) {
- ret = 0;
- }
-
- fscache_put_operation(op);
- _leave(" = %d", ret);
- return ret;
-
-submit_failed:
- wake_cookie = __fscache_unuse_cookie(cookie);
-inconsistent:
- spin_unlock(&cookie->lock);
- if (wake_cookie)
- __fscache_wake_unused_cookie(cookie);
- kfree(op);
- _leave(" = -ESTALE");
- return -ESTALE;
-}
-EXPORT_SYMBOL(__fscache_check_consistency);
-
-/*
- * Generate a list of extant cookies in /proc/fs/fscache/cookies
- */
-static int fscache_cookies_seq_show(struct seq_file *m, void *v)
-{
- struct fscache_cookie *cookie;
- unsigned int keylen = 0, auxlen = 0;
- char _type[3], *type;
- u8 *p;
-
- if (v == &fscache_cookies) {
- seq_puts(m,
- "COOKIE PARENT USAGE CHILD ACT TY FL DEF NETFS_DATA\n"
- "======== ======== ===== ===== === == === ================ ==========\n"
- );
- return 0;
- }
-
- cookie = list_entry(v, struct fscache_cookie, proc_link);
-
- switch (cookie->type) {
- case 0:
- type = "IX";
- break;
- case 1:
- type = "DT";
- break;
- default:
- snprintf(_type, sizeof(_type), "%02u",
- cookie->type);
- type = _type;
- break;
- }
-
- seq_printf(m,
- "%08x %08x %5u %5u %3u %s %03lx %-16s %px",
- cookie->debug_id,
- cookie->parent ? cookie->parent->debug_id : 0,
- refcount_read(&cookie->ref),
- atomic_read(&cookie->n_children),
- atomic_read(&cookie->n_active),
- type,
- cookie->flags,
- cookie->def->name,
- cookie->netfs_data);
-
- keylen = cookie->key_len;
- auxlen = cookie->aux_len;
-
- if (keylen > 0 || auxlen > 0) {
- seq_puts(m, " ");
- p = keylen <= sizeof(cookie->inline_key) ?
- cookie->inline_key : cookie->key;
- for (; keylen > 0; keylen--)
- seq_printf(m, "%02x", *p++);
- if (auxlen > 0) {
- seq_puts(m, ", ");
- p = auxlen <= sizeof(cookie->inline_aux) ?
- cookie->inline_aux : cookie->aux;
- for (; auxlen > 0; auxlen--)
- seq_printf(m, "%02x", *p++);
- }
- }
-
- seq_puts(m, "\n");
- return 0;
-}
-
-static void *fscache_cookies_seq_start(struct seq_file *m, loff_t *_pos)
- __acquires(fscache_cookies_lock)
-{
- read_lock(&fscache_cookies_lock);
- return seq_list_start_head(&fscache_cookies, *_pos);
-}
-
-static void *fscache_cookies_seq_next(struct seq_file *m, void *v, loff_t *_pos)
-{
- return seq_list_next(v, &fscache_cookies, _pos);
-}
-
-static void fscache_cookies_seq_stop(struct seq_file *m, void *v)
- __releases(rcu)
-{
- read_unlock(&fscache_cookies_lock);
-}
-
-
-const struct seq_operations fscache_cookies_seq_ops = {
- .start = fscache_cookies_seq_start,
- .next = fscache_cookies_seq_next,
- .stop = fscache_cookies_seq_stop,
- .show = fscache_cookies_seq_show,
-};
+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* Filesystem index definition
- *
- * Copyright (C) 2004-2007 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- */
-
-#define FSCACHE_DEBUG_LEVEL CACHE
-#include <linux/module.h>
-#include "internal.h"
-
-static
-enum fscache_checkaux fscache_fsdef_netfs_check_aux(void *cookie_netfs_data,
- const void *data,
- uint16_t datalen,
- loff_t object_size);
-
-/*
- * The root index is owned by FS-Cache itself.
- *
- * When a netfs requests caching facilities, FS-Cache will, if one doesn't
- * already exist, create an entry in the root index with the key being the name
- * of the netfs ("AFS" for example), and the auxiliary data holding the index
- * structure version supplied by the netfs:
- *
- * FSDEF
- * |
- * +-----------+
- * | |
- * NFS AFS
- * [v=1] [v=1]
- *
- * If an entry with the appropriate name does already exist, the version is
- * compared. If the version is different, the entire subtree from that entry
- * will be discarded and a new entry created.
- *
- * The new entry will be an index, and a cookie referring to it will be passed
- * to the netfs. This is then the root handle by which the netfs accesses the
- * cache. It can create whatever objects it likes in that index, including
- * further indices.
- */
-static struct fscache_cookie_def fscache_fsdef_index_def = {
- .name = ".FS-Cache",
- .type = FSCACHE_COOKIE_TYPE_INDEX,
-};
-
-struct fscache_cookie fscache_fsdef_index = {
- .debug_id = 1,
- .ref = REFCOUNT_INIT(1),
- .n_active = ATOMIC_INIT(1),
- .lock = __SPIN_LOCK_UNLOCKED(fscache_fsdef_index.lock),
- .backing_objects = HLIST_HEAD_INIT,
- .def = &fscache_fsdef_index_def,
- .flags = 1 << FSCACHE_COOKIE_ENABLED,
- .type = FSCACHE_COOKIE_TYPE_INDEX,
-};
-EXPORT_SYMBOL(fscache_fsdef_index);
-
-/*
- * Definition of an entry in the root index. Each entry is an index, keyed to
- * a specific netfs and only applicable to a particular version of the index
- * structure used by that netfs.
- */
-struct fscache_cookie_def fscache_fsdef_netfs_def = {
- .name = "FSDEF.netfs",
- .type = FSCACHE_COOKIE_TYPE_INDEX,
- .check_aux = fscache_fsdef_netfs_check_aux,
-};
-
-/*
- * check that the index structure version number stored in the auxiliary data
- * matches the one the netfs gave us
- */
-static enum fscache_checkaux fscache_fsdef_netfs_check_aux(
- void *cookie_netfs_data,
- const void *data,
- uint16_t datalen,
- loff_t object_size)
-{
- struct fscache_netfs *netfs = cookie_netfs_data;
- uint32_t version;
-
- _enter("{%s},,%hu", netfs->name, datalen);
-
- if (datalen != sizeof(version)) {
- _leave(" = OBSOLETE [dl=%d v=%zu]", datalen, sizeof(version));
- return FSCACHE_CHECKAUX_OBSOLETE;
- }
-
- memcpy(&version, data, sizeof(version));
- if (version != netfs->version) {
- _leave(" = OBSOLETE [ver=%x net=%x]", version, netfs->version);
- return FSCACHE_CHECKAUX_OBSOLETE;
- }
-
- _leave(" = OKAY");
- return FSCACHE_CHECKAUX_OKAY;
-}
+++ /dev/null
-/* SPDX-License-Identifier: GPL-2.0-or-later */
-/* Internal definitions for FS-Cache
- *
- * Copyright (C) 2004-2007 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- */
-
-/*
- * Lock order, in the order in which multiple locks should be obtained:
- * - fscache_addremove_sem
- * - cookie->lock
- * - cookie->parent->lock
- * - cache->object_list_lock
- * - object->lock
- * - object->parent->lock
- * - cookie->stores_lock
- * - fscache_thread_lock
- *
- */
-
-#ifdef pr_fmt
-#undef pr_fmt
-#endif
-
-#define pr_fmt(fmt) "FS-Cache: " fmt
-
-#include <linux/fscache-cache.h>
-#include <trace/events/fscache.h>
-#include <linux/sched.h>
-#include <linux/seq_file.h>
-
-#define FSCACHE_MIN_THREADS 4
-#define FSCACHE_MAX_THREADS 32
-
-/*
- * cache.c
- */
-extern struct list_head fscache_cache_list;
-extern struct rw_semaphore fscache_addremove_sem;
-
-extern struct fscache_cache *fscache_select_cache_for_object(
- struct fscache_cookie *);
-
-/*
- * cookie.c
- */
-extern struct kmem_cache *fscache_cookie_jar;
-extern const struct seq_operations fscache_cookies_seq_ops;
-
-extern void fscache_free_cookie(struct fscache_cookie *);
-extern struct fscache_cookie *fscache_alloc_cookie(struct fscache_cookie *,
- const struct fscache_cookie_def *,
- const void *, size_t,
- const void *, size_t,
- void *, loff_t);
-extern struct fscache_cookie *fscache_hash_cookie(struct fscache_cookie *);
-extern struct fscache_cookie *fscache_cookie_get(struct fscache_cookie *,
- enum fscache_cookie_trace);
-extern void fscache_cookie_put(struct fscache_cookie *,
- enum fscache_cookie_trace);
-
-static inline void fscache_cookie_see(struct fscache_cookie *cookie,
- enum fscache_cookie_trace where)
-{
- trace_fscache_cookie(cookie->debug_id, refcount_read(&cookie->ref),
- where);
-}
-
-/*
- * fsdef.c
- */
-extern struct fscache_cookie fscache_fsdef_index;
-extern struct fscache_cookie_def fscache_fsdef_netfs_def;
-
-/*
- * main.c
- */
-extern unsigned fscache_defer_lookup;
-extern unsigned fscache_defer_create;
-extern unsigned fscache_debug;
-extern struct kobject *fscache_root;
-extern struct workqueue_struct *fscache_object_wq;
-extern struct workqueue_struct *fscache_op_wq;
-DECLARE_PER_CPU(wait_queue_head_t, fscache_object_cong_wait);
-
-extern unsigned int fscache_hash(unsigned int salt, unsigned int *data, unsigned int n);
-
-static inline bool fscache_object_congested(void)
-{
- return workqueue_congested(WORK_CPU_UNBOUND, fscache_object_wq);
-}
-
-/*
- * object.c
- */
-extern void fscache_enqueue_object(struct fscache_object *);
-
-/*
- * operation.c
- */
-extern int fscache_submit_exclusive_op(struct fscache_object *,
- struct fscache_operation *);
-extern int fscache_submit_op(struct fscache_object *,
- struct fscache_operation *);
-extern int fscache_cancel_op(struct fscache_operation *, bool);
-extern void fscache_cancel_all_ops(struct fscache_object *);
-extern void fscache_abort_object(struct fscache_object *);
-extern void fscache_start_operations(struct fscache_object *);
-extern void fscache_operation_gc(struct work_struct *);
-
-/*
- * page.c
- */
-extern int fscache_wait_for_deferred_lookup(struct fscache_cookie *);
-extern int fscache_wait_for_operation_activation(struct fscache_object *,
- struct fscache_operation *,
- atomic_t *,
- atomic_t *);
-extern void fscache_invalidate_writes(struct fscache_cookie *);
-struct fscache_retrieval *fscache_alloc_retrieval(struct fscache_cookie *cookie,
- struct address_space *mapping,
- fscache_rw_complete_t end_io_func,
- void *context);
-
-/*
- * proc.c
- */
-#ifdef CONFIG_PROC_FS
-extern int __init fscache_proc_init(void);
-extern void fscache_proc_cleanup(void);
-#else
-#define fscache_proc_init() (0)
-#define fscache_proc_cleanup() do {} while (0)
-#endif
-
-/*
- * stats.c
- */
-#ifdef CONFIG_FSCACHE_STATS
-extern atomic_t fscache_n_ops_processed[FSCACHE_MAX_THREADS];
-extern atomic_t fscache_n_objs_processed[FSCACHE_MAX_THREADS];
-
-extern atomic_t fscache_n_op_pend;
-extern atomic_t fscache_n_op_run;
-extern atomic_t fscache_n_op_enqueue;
-extern atomic_t fscache_n_op_deferred_release;
-extern atomic_t fscache_n_op_initialised;
-extern atomic_t fscache_n_op_release;
-extern atomic_t fscache_n_op_gc;
-extern atomic_t fscache_n_op_cancelled;
-extern atomic_t fscache_n_op_rejected;
-
-extern atomic_t fscache_n_attr_changed;
-extern atomic_t fscache_n_attr_changed_ok;
-extern atomic_t fscache_n_attr_changed_nobufs;
-extern atomic_t fscache_n_attr_changed_nomem;
-extern atomic_t fscache_n_attr_changed_calls;
-
-extern atomic_t fscache_n_allocs;
-extern atomic_t fscache_n_allocs_ok;
-extern atomic_t fscache_n_allocs_wait;
-extern atomic_t fscache_n_allocs_nobufs;
-extern atomic_t fscache_n_allocs_intr;
-extern atomic_t fscache_n_allocs_object_dead;
-extern atomic_t fscache_n_alloc_ops;
-extern atomic_t fscache_n_alloc_op_waits;
-
-extern atomic_t fscache_n_retrievals;
-extern atomic_t fscache_n_retrievals_ok;
-extern atomic_t fscache_n_retrievals_wait;
-extern atomic_t fscache_n_retrievals_nodata;
-extern atomic_t fscache_n_retrievals_nobufs;
-extern atomic_t fscache_n_retrievals_intr;
-extern atomic_t fscache_n_retrievals_nomem;
-extern atomic_t fscache_n_retrievals_object_dead;
-extern atomic_t fscache_n_retrieval_ops;
-extern atomic_t fscache_n_retrieval_op_waits;
-
-extern atomic_t fscache_n_stores;
-extern atomic_t fscache_n_stores_ok;
-extern atomic_t fscache_n_stores_again;
-extern atomic_t fscache_n_stores_nobufs;
-extern atomic_t fscache_n_stores_oom;
-extern atomic_t fscache_n_store_ops;
-extern atomic_t fscache_n_store_calls;
-extern atomic_t fscache_n_store_pages;
-extern atomic_t fscache_n_store_radix_deletes;
-extern atomic_t fscache_n_store_pages_over_limit;
-
-extern atomic_t fscache_n_store_vmscan_not_storing;
-extern atomic_t fscache_n_store_vmscan_gone;
-extern atomic_t fscache_n_store_vmscan_busy;
-extern atomic_t fscache_n_store_vmscan_cancelled;
-extern atomic_t fscache_n_store_vmscan_wait;
-
-extern atomic_t fscache_n_marks;
-extern atomic_t fscache_n_uncaches;
-
-extern atomic_t fscache_n_acquires;
-extern atomic_t fscache_n_acquires_null;
-extern atomic_t fscache_n_acquires_no_cache;
-extern atomic_t fscache_n_acquires_ok;
-extern atomic_t fscache_n_acquires_nobufs;
-extern atomic_t fscache_n_acquires_oom;
-
-extern atomic_t fscache_n_invalidates;
-extern atomic_t fscache_n_invalidates_run;
-
-extern atomic_t fscache_n_updates;
-extern atomic_t fscache_n_updates_null;
-extern atomic_t fscache_n_updates_run;
-
-extern atomic_t fscache_n_relinquishes;
-extern atomic_t fscache_n_relinquishes_null;
-extern atomic_t fscache_n_relinquishes_waitcrt;
-extern atomic_t fscache_n_relinquishes_retire;
-
-extern atomic_t fscache_n_cookie_index;
-extern atomic_t fscache_n_cookie_data;
-extern atomic_t fscache_n_cookie_special;
-
-extern atomic_t fscache_n_object_alloc;
-extern atomic_t fscache_n_object_no_alloc;
-extern atomic_t fscache_n_object_lookups;
-extern atomic_t fscache_n_object_lookups_negative;
-extern atomic_t fscache_n_object_lookups_positive;
-extern atomic_t fscache_n_object_lookups_timed_out;
-extern atomic_t fscache_n_object_created;
-extern atomic_t fscache_n_object_avail;
-extern atomic_t fscache_n_object_dead;
-
-extern atomic_t fscache_n_checkaux_none;
-extern atomic_t fscache_n_checkaux_okay;
-extern atomic_t fscache_n_checkaux_update;
-extern atomic_t fscache_n_checkaux_obsolete;
-
-extern atomic_t fscache_n_cop_alloc_object;
-extern atomic_t fscache_n_cop_lookup_object;
-extern atomic_t fscache_n_cop_lookup_complete;
-extern atomic_t fscache_n_cop_grab_object;
-extern atomic_t fscache_n_cop_invalidate_object;
-extern atomic_t fscache_n_cop_update_object;
-extern atomic_t fscache_n_cop_drop_object;
-extern atomic_t fscache_n_cop_put_object;
-extern atomic_t fscache_n_cop_sync_cache;
-extern atomic_t fscache_n_cop_attr_changed;
-extern atomic_t fscache_n_cop_read_or_alloc_page;
-extern atomic_t fscache_n_cop_read_or_alloc_pages;
-extern atomic_t fscache_n_cop_allocate_page;
-extern atomic_t fscache_n_cop_allocate_pages;
-extern atomic_t fscache_n_cop_write_page;
-extern atomic_t fscache_n_cop_uncache_page;
-extern atomic_t fscache_n_cop_dissociate_pages;
-
-extern atomic_t fscache_n_cache_no_space_reject;
-extern atomic_t fscache_n_cache_stale_objects;
-extern atomic_t fscache_n_cache_retired_objects;
-extern atomic_t fscache_n_cache_culled_objects;
-
-static inline void fscache_stat(atomic_t *stat)
-{
- atomic_inc(stat);
-}
-
-static inline void fscache_stat_d(atomic_t *stat)
-{
- atomic_dec(stat);
-}
-
-#define __fscache_stat(stat) (stat)
-
-int fscache_stats_show(struct seq_file *m, void *v);
-#else
-
-#define __fscache_stat(stat) (NULL)
-#define fscache_stat(stat) do {} while (0)
-#define fscache_stat_d(stat) do {} while (0)
-#endif
-
-/*
- * raise an event on an object
- * - if the event is not masked for that object, then the object is
- * queued for attention by the thread pool.
- */
-static inline void fscache_raise_event(struct fscache_object *object,
- unsigned event)
-{
- BUG_ON(event >= NR_FSCACHE_OBJECT_EVENTS);
-#if 0
- printk("*** fscache_raise_event(OBJ%d{%lx},%x)\n",
- object->debug_id, object->event_mask, (1 << event));
-#endif
- if (!test_and_set_bit(event, &object->events) &&
- test_bit(event, &object->event_mask))
- fscache_enqueue_object(object);
-}
-
-/*
- * get an extra reference to a netfs retrieval context
- */
-static inline
-void *fscache_get_context(struct fscache_cookie *cookie, void *context)
-{
- if (cookie->def->get_context)
- cookie->def->get_context(cookie->netfs_data, context);
- return context;
-}
-
-/*
- * release a reference to a netfs retrieval context
- */
-static inline
-void fscache_put_context(struct fscache_cookie *cookie, void *context)
-{
- if (cookie->def->put_context)
- cookie->def->put_context(cookie->netfs_data, context);
-}
-
-/*
- * Update the auxiliary data on a cookie.
- */
-static inline
-void fscache_update_aux(struct fscache_cookie *cookie, const void *aux_data)
-{
- void *p;
-
- if (!aux_data)
- return;
- if (cookie->aux_len <= sizeof(cookie->inline_aux))
- p = cookie->inline_aux;
- else
- p = cookie->aux;
-
- if (memcmp(p, aux_data, cookie->aux_len) != 0) {
- memcpy(p, aux_data, cookie->aux_len);
- set_bit(FSCACHE_COOKIE_AUX_UPDATED, &cookie->flags);
- }
-}
-
-/*****************************************************************************/
-/*
- * debug tracing
- */
-#define dbgprintk(FMT, ...) \
- printk(KERN_DEBUG "[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)
-
-#define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
-#define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
-#define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__)
-
-#define kjournal(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
-
-#ifdef __KDEBUG
-#define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__)
-#define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__)
-#define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__)
-
-#elif defined(CONFIG_FSCACHE_DEBUG)
-#define _enter(FMT, ...) \
-do { \
- if (__do_kdebug(ENTER)) \
- kenter(FMT, ##__VA_ARGS__); \
-} while (0)
-
-#define _leave(FMT, ...) \
-do { \
- if (__do_kdebug(LEAVE)) \
- kleave(FMT, ##__VA_ARGS__); \
-} while (0)
-
-#define _debug(FMT, ...) \
-do { \
- if (__do_kdebug(DEBUG)) \
- kdebug(FMT, ##__VA_ARGS__); \
-} while (0)
-
-#else
-#define _enter(FMT, ...) no_printk("==> %s("FMT")", __func__, ##__VA_ARGS__)
-#define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
-#define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
-#endif
-
-/*
- * determine whether a particular optional debugging point should be logged
- * - we need to go through three steps to persuade cpp to correctly join the
- * shorthand in FSCACHE_DEBUG_LEVEL with its prefix
- */
-#define ____do_kdebug(LEVEL, POINT) \
- unlikely((fscache_debug & \
- (FSCACHE_POINT_##POINT << (FSCACHE_DEBUG_ ## LEVEL * 3))))
-#define ___do_kdebug(LEVEL, POINT) \
- ____do_kdebug(LEVEL, POINT)
-#define __do_kdebug(POINT) \
- ___do_kdebug(FSCACHE_DEBUG_LEVEL, POINT)
-
-#define FSCACHE_DEBUG_CACHE 0
-#define FSCACHE_DEBUG_COOKIE 1
-#define FSCACHE_DEBUG_PAGE 2
-#define FSCACHE_DEBUG_OPERATION 3
-
-#define FSCACHE_POINT_ENTER 1
-#define FSCACHE_POINT_LEAVE 2
-#define FSCACHE_POINT_DEBUG 4
-
-#ifndef FSCACHE_DEBUG_LEVEL
-#define FSCACHE_DEBUG_LEVEL CACHE
-#endif
-
-/*
- * assertions
- */
-#if 1 /* defined(__KDEBUGALL) */
-
-#define ASSERT(X) \
-do { \
- if (unlikely(!(X))) { \
- pr_err("\n"); \
- pr_err("Assertion failed\n"); \
- BUG(); \
- } \
-} while (0)
-
-#define ASSERTCMP(X, OP, Y) \
-do { \
- if (unlikely(!((X) OP (Y)))) { \
- pr_err("\n"); \
- pr_err("Assertion failed\n"); \
- pr_err("%lx " #OP " %lx is false\n", \
- (unsigned long)(X), (unsigned long)(Y)); \
- BUG(); \
- } \
-} while (0)
-
-#define ASSERTIF(C, X) \
-do { \
- if (unlikely((C) && !(X))) { \
- pr_err("\n"); \
- pr_err("Assertion failed\n"); \
- BUG(); \
- } \
-} while (0)
-
-#define ASSERTIFCMP(C, X, OP, Y) \
-do { \
- if (unlikely((C) && !((X) OP (Y)))) { \
- pr_err("\n"); \
- pr_err("Assertion failed\n"); \
- pr_err("%lx " #OP " %lx is false\n", \
- (unsigned long)(X), (unsigned long)(Y)); \
- BUG(); \
- } \
-} while (0)
-
-#else
-
-#define ASSERT(X) do {} while (0)
-#define ASSERTCMP(X, OP, Y) do {} while (0)
-#define ASSERTIF(C, X) do {} while (0)
-#define ASSERTIFCMP(C, X, OP, Y) do {} while (0)
-
-#endif /* assert or not */
+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* Cache data I/O routines
- *
- * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- */
-
-#define FSCACHE_DEBUG_LEVEL PAGE
-#include <linux/module.h>
-#define FSCACHE_USE_NEW_IO_API
-#include <linux/fscache-cache.h>
-#include <linux/slab.h>
-#include <linux/netfs.h>
-#include "internal.h"
-
-/*
- * Start a cache read operation.
- * - we return:
- * -ENOMEM - out of memory, some pages may be being read
- * -ERESTARTSYS - interrupted, some pages may be being read
- * -ENOBUFS - no backing object or space available in which to cache any
- * pages not being read
- * -ENODATA - no data available in the backing object for some or all of
- * the pages
- * 0 - dispatched a read on all pages
- */
-int __fscache_begin_read_operation(struct netfs_read_request *rreq,
- struct fscache_cookie *cookie)
-{
- struct fscache_retrieval *op;
- struct fscache_object *object;
- bool wake_cookie = false;
- int ret;
-
- _enter("rr=%08x", rreq->debug_id);
-
- fscache_stat(&fscache_n_retrievals);
-
- if (hlist_empty(&cookie->backing_objects))
- goto nobufs;
-
- if (test_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags)) {
- _leave(" = -ENOBUFS [invalidating]");
- return -ENOBUFS;
- }
-
- ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX);
-
- if (fscache_wait_for_deferred_lookup(cookie) < 0)
- return -ERESTARTSYS;
-
- op = fscache_alloc_retrieval(cookie, NULL, NULL, NULL);
- if (!op)
- return -ENOMEM;
- trace_fscache_page_op(cookie, NULL, &op->op, fscache_page_op_retr_multi);
-
- spin_lock(&cookie->lock);
-
- if (!fscache_cookie_enabled(cookie) ||
- hlist_empty(&cookie->backing_objects))
- goto nobufs_unlock;
- object = hlist_entry(cookie->backing_objects.first,
- struct fscache_object, cookie_link);
-
- __fscache_use_cookie(cookie);
- atomic_inc(&object->n_reads);
- __set_bit(FSCACHE_OP_DEC_READ_CNT, &op->op.flags);
-
- if (fscache_submit_op(object, &op->op) < 0)
- goto nobufs_unlock_dec;
- spin_unlock(&cookie->lock);
-
- fscache_stat(&fscache_n_retrieval_ops);
-
- /* we wait for the operation to become active, and then process it
- * *here*, in this thread, and not in the thread pool */
- ret = fscache_wait_for_operation_activation(
- object, &op->op,
- __fscache_stat(&fscache_n_retrieval_op_waits),
- __fscache_stat(&fscache_n_retrievals_object_dead));
- if (ret < 0)
- goto error;
-
- /* ask the cache to honour the operation */
- ret = object->cache->ops->begin_read_operation(rreq, op);
-
-error:
- if (ret == -ENOMEM)
- fscache_stat(&fscache_n_retrievals_nomem);
- else if (ret == -ERESTARTSYS)
- fscache_stat(&fscache_n_retrievals_intr);
- else if (ret == -ENODATA)
- fscache_stat(&fscache_n_retrievals_nodata);
- else if (ret < 0)
- fscache_stat(&fscache_n_retrievals_nobufs);
- else
- fscache_stat(&fscache_n_retrievals_ok);
-
- fscache_put_retrieval(op);
- _leave(" = %d", ret);
- return ret;
-
-nobufs_unlock_dec:
- atomic_dec(&object->n_reads);
- wake_cookie = __fscache_unuse_cookie(cookie);
-nobufs_unlock:
- spin_unlock(&cookie->lock);
- fscache_put_retrieval(op);
- if (wake_cookie)
- __fscache_wake_unused_cookie(cookie);
-nobufs:
- fscache_stat(&fscache_n_retrievals_nobufs);
- _leave(" = -ENOBUFS");
- return -ENOBUFS;
-}
-EXPORT_SYMBOL(__fscache_begin_read_operation);
+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* General filesystem local caching manager
- *
- * Copyright (C) 2004-2007 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- */
-
-#define FSCACHE_DEBUG_LEVEL CACHE
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/sched.h>
-#include <linux/completion.h>
-#include <linux/slab.h>
-#include <linux/seq_file.h>
-#define CREATE_TRACE_POINTS
-#include "internal.h"
-
-MODULE_DESCRIPTION("FS Cache Manager");
-MODULE_AUTHOR("Red Hat, Inc.");
-MODULE_LICENSE("GPL");
-
-unsigned fscache_defer_lookup = 1;
-module_param_named(defer_lookup, fscache_defer_lookup, uint,
- S_IWUSR | S_IRUGO);
-MODULE_PARM_DESC(fscache_defer_lookup,
- "Defer cookie lookup to background thread");
-
-unsigned fscache_defer_create = 1;
-module_param_named(defer_create, fscache_defer_create, uint,
- S_IWUSR | S_IRUGO);
-MODULE_PARM_DESC(fscache_defer_create,
- "Defer cookie creation to background thread");
-
-unsigned fscache_debug;
-module_param_named(debug, fscache_debug, uint,
- S_IWUSR | S_IRUGO);
-MODULE_PARM_DESC(fscache_debug,
- "FS-Cache debugging mask");
-
-struct kobject *fscache_root;
-struct workqueue_struct *fscache_object_wq;
-struct workqueue_struct *fscache_op_wq;
-
-DEFINE_PER_CPU(wait_queue_head_t, fscache_object_cong_wait);
-
-/* these values serve as lower bounds, will be adjusted in fscache_init() */
-static unsigned fscache_object_max_active = 4;
-static unsigned fscache_op_max_active = 2;
-
-#ifdef CONFIG_SYSCTL
-static struct ctl_table_header *fscache_sysctl_header;
-
-static int fscache_max_active_sysctl(struct ctl_table *table, int write,
- void *buffer, size_t *lenp, loff_t *ppos)
-{
- struct workqueue_struct **wqp = table->extra1;
- unsigned int *datap = table->data;
- int ret;
-
- ret = proc_dointvec(table, write, buffer, lenp, ppos);
- if (ret == 0)
- workqueue_set_max_active(*wqp, *datap);
- return ret;
-}
-
-static struct ctl_table fscache_sysctls[] = {
- {
- .procname = "object_max_active",
- .data = &fscache_object_max_active,
- .maxlen = sizeof(unsigned),
- .mode = 0644,
- .proc_handler = fscache_max_active_sysctl,
- .extra1 = &fscache_object_wq,
- },
- {
- .procname = "operation_max_active",
- .data = &fscache_op_max_active,
- .maxlen = sizeof(unsigned),
- .mode = 0644,
- .proc_handler = fscache_max_active_sysctl,
- .extra1 = &fscache_op_wq,
- },
- {}
-};
-
-static struct ctl_table fscache_sysctls_root[] = {
- {
- .procname = "fscache",
- .mode = 0555,
- .child = fscache_sysctls,
- },
- {}
-};
-#endif
-
-/*
- * Mixing scores (in bits) for (7,20):
- * Input delta: 1-bit 2-bit
- * 1 round: 330.3 9201.6
- * 2 rounds: 1246.4 25475.4
- * 3 rounds: 1907.1 31295.1
- * 4 rounds: 2042.3 31718.6
- * Perfect: 2048 31744
- * (32*64) (32*31/2 * 64)
- */
-#define HASH_MIX(x, y, a) \
- ( x ^= (a), \
- y ^= x, x = rol32(x, 7),\
- x += y, y = rol32(y,20),\
- y *= 9 )
-
-static inline unsigned int fold_hash(unsigned long x, unsigned long y)
-{
- /* Use arch-optimized multiply if one exists */
- return __hash_32(y ^ __hash_32(x));
-}
-
-/*
- * Generate a hash. This is derived from full_name_hash(), but we want to be
- * sure it is arch independent and that it doesn't change as bits of the
- * computed hash value might appear on disk. The caller also guarantees that
- * the hashed data will be a series of aligned 32-bit words.
- */
-unsigned int fscache_hash(unsigned int salt, unsigned int *data, unsigned int n)
-{
- unsigned int a, x = 0, y = salt;
-
- for (; n; n--) {
- a = *data++;
- HASH_MIX(x, y, a);
- }
- return fold_hash(x, y);
-}
-
-/*
- * initialise the fs caching module
- */
-static int __init fscache_init(void)
-{
- unsigned int nr_cpus = num_possible_cpus();
- unsigned int cpu;
- int ret;
-
- fscache_object_max_active =
- clamp_val(nr_cpus,
- fscache_object_max_active, WQ_UNBOUND_MAX_ACTIVE);
-
- ret = -ENOMEM;
- fscache_object_wq = alloc_workqueue("fscache_object", WQ_UNBOUND,
- fscache_object_max_active);
- if (!fscache_object_wq)
- goto error_object_wq;
-
- fscache_op_max_active =
- clamp_val(fscache_object_max_active / 2,
- fscache_op_max_active, WQ_UNBOUND_MAX_ACTIVE);
-
- ret = -ENOMEM;
- fscache_op_wq = alloc_workqueue("fscache_operation", WQ_UNBOUND,
- fscache_op_max_active);
- if (!fscache_op_wq)
- goto error_op_wq;
-
- for_each_possible_cpu(cpu)
- init_waitqueue_head(&per_cpu(fscache_object_cong_wait, cpu));
-
- ret = fscache_proc_init();
- if (ret < 0)
- goto error_proc;
-
-#ifdef CONFIG_SYSCTL
- ret = -ENOMEM;
- fscache_sysctl_header = register_sysctl_table(fscache_sysctls_root);
- if (!fscache_sysctl_header)
- goto error_sysctl;
-#endif
-
- fscache_cookie_jar = kmem_cache_create("fscache_cookie_jar",
- sizeof(struct fscache_cookie),
- 0, 0, NULL);
- if (!fscache_cookie_jar) {
- pr_notice("Failed to allocate a cookie jar\n");
- ret = -ENOMEM;
- goto error_cookie_jar;
- }
-
- fscache_root = kobject_create_and_add("fscache", kernel_kobj);
- if (!fscache_root)
- goto error_kobj;
-
- pr_notice("Loaded\n");
- return 0;
-
-error_kobj:
- kmem_cache_destroy(fscache_cookie_jar);
-error_cookie_jar:
-#ifdef CONFIG_SYSCTL
- unregister_sysctl_table(fscache_sysctl_header);
-error_sysctl:
-#endif
- fscache_proc_cleanup();
-error_proc:
- destroy_workqueue(fscache_op_wq);
-error_op_wq:
- destroy_workqueue(fscache_object_wq);
-error_object_wq:
- return ret;
-}
-
-fs_initcall(fscache_init);
-
-/*
- * clean up on module removal
- */
-static void __exit fscache_exit(void)
-{
- _enter("");
-
- kobject_put(fscache_root);
- kmem_cache_destroy(fscache_cookie_jar);
-#ifdef CONFIG_SYSCTL
- unregister_sysctl_table(fscache_sysctl_header);
-#endif
- fscache_proc_cleanup();
- destroy_workqueue(fscache_op_wq);
- destroy_workqueue(fscache_object_wq);
- pr_notice("Unloaded\n");
-}
-
-module_exit(fscache_exit);
+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* FS-Cache netfs (client) registration
- *
- * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- */
-
-#define FSCACHE_DEBUG_LEVEL COOKIE
-#include <linux/module.h>
-#include <linux/slab.h>
-#include "internal.h"
-
-/*
- * register a network filesystem for caching
- */
-int __fscache_register_netfs(struct fscache_netfs *netfs)
-{
- struct fscache_cookie *candidate, *cookie;
-
- _enter("{%s}", netfs->name);
-
- /* allocate a cookie for the primary index */
- candidate = fscache_alloc_cookie(&fscache_fsdef_index,
- &fscache_fsdef_netfs_def,
- netfs->name, strlen(netfs->name),
- &netfs->version, sizeof(netfs->version),
- netfs, 0);
- if (!candidate) {
- _leave(" = -ENOMEM");
- return -ENOMEM;
- }
-
- candidate->flags = 1 << FSCACHE_COOKIE_ENABLED;
-
- /* check the netfs type is not already present */
- cookie = fscache_hash_cookie(candidate);
- if (!cookie)
- goto already_registered;
- if (cookie != candidate) {
- trace_fscache_cookie(candidate->debug_id, 1, fscache_cookie_discard);
- fscache_free_cookie(candidate);
- }
-
- fscache_cookie_get(cookie->parent, fscache_cookie_get_register_netfs);
- atomic_inc(&cookie->parent->n_children);
-
- netfs->primary_index = cookie;
-
- pr_notice("Netfs '%s' registered for caching\n", netfs->name);
- trace_fscache_netfs(netfs);
- _leave(" = 0");
- return 0;
-
-already_registered:
- fscache_cookie_put(candidate, fscache_cookie_put_dup_netfs);
- _leave(" = -EEXIST");
- return -EEXIST;
-}
-EXPORT_SYMBOL(__fscache_register_netfs);
-
-/*
- * unregister a network filesystem from the cache
- * - all cookies must have been released first
- */
-void __fscache_unregister_netfs(struct fscache_netfs *netfs)
-{
- _enter("{%s.%u}", netfs->name, netfs->version);
-
- fscache_relinquish_cookie(netfs->primary_index, NULL, false);
- pr_notice("Netfs '%s' unregistered from caching\n", netfs->name);
-
- _leave("");
-}
-EXPORT_SYMBOL(__fscache_unregister_netfs);
+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* FS-Cache object state machine handler
- *
- * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- *
- * See Documentation/filesystems/caching/object.rst for a description of the
- * object state machine and the in-kernel representations.
- */
-
-#define FSCACHE_DEBUG_LEVEL COOKIE
-#include <linux/module.h>
-#include <linux/slab.h>
-#include <linux/prefetch.h>
-#include "internal.h"
-
-static const struct fscache_state *fscache_abort_initialisation(struct fscache_object *, int);
-static const struct fscache_state *fscache_kill_dependents(struct fscache_object *, int);
-static const struct fscache_state *fscache_drop_object(struct fscache_object *, int);
-static const struct fscache_state *fscache_initialise_object(struct fscache_object *, int);
-static const struct fscache_state *fscache_invalidate_object(struct fscache_object *, int);
-static const struct fscache_state *fscache_jumpstart_dependents(struct fscache_object *, int);
-static const struct fscache_state *fscache_kill_object(struct fscache_object *, int);
-static const struct fscache_state *fscache_lookup_failure(struct fscache_object *, int);
-static const struct fscache_state *fscache_look_up_object(struct fscache_object *, int);
-static const struct fscache_state *fscache_object_available(struct fscache_object *, int);
-static const struct fscache_state *fscache_parent_ready(struct fscache_object *, int);
-static const struct fscache_state *fscache_update_object(struct fscache_object *, int);
-static const struct fscache_state *fscache_object_dead(struct fscache_object *, int);
-
-#define __STATE_NAME(n) fscache_osm_##n
-#define STATE(n) (&__STATE_NAME(n))
-
-/*
- * Define a work state. Work states are execution states. No event processing
- * is performed by them. The function attached to a work state returns a
- * pointer indicating the next state to which the state machine should
- * transition. Returning NO_TRANSIT repeats the current state, but goes back
- * to the scheduler first.
- */
-#define WORK_STATE(n, sn, f) \
- const struct fscache_state __STATE_NAME(n) = { \
- .name = #n, \
- .short_name = sn, \
- .work = f \
- }
-
-/*
- * Returns from work states.
- */
-#define transit_to(state) ({ prefetch(&STATE(state)->work); STATE(state); })
-
-#define NO_TRANSIT ((struct fscache_state *)NULL)
-
-/*
- * Define a wait state. Wait states are event processing states. No execution
- * is performed by them. Wait states are just tables of "if event X occurs,
- * clear it and transition to state Y". The dispatcher returns to the
- * scheduler if none of the events in which the wait state has an interest are
- * currently pending.
- */
-#define WAIT_STATE(n, sn, ...) \
- const struct fscache_state __STATE_NAME(n) = { \
- .name = #n, \
- .short_name = sn, \
- .work = NULL, \
- .transitions = { __VA_ARGS__, { 0, NULL } } \
- }
-
-#define TRANSIT_TO(state, emask) \
- { .events = (emask), .transit_to = STATE(state) }
-
-/*
- * The object state machine.
- */
-static WORK_STATE(INIT_OBJECT, "INIT", fscache_initialise_object);
-static WORK_STATE(PARENT_READY, "PRDY", fscache_parent_ready);
-static WORK_STATE(ABORT_INIT, "ABRT", fscache_abort_initialisation);
-static WORK_STATE(LOOK_UP_OBJECT, "LOOK", fscache_look_up_object);
-static WORK_STATE(OBJECT_AVAILABLE, "AVBL", fscache_object_available);
-static WORK_STATE(JUMPSTART_DEPS, "JUMP", fscache_jumpstart_dependents);
-
-static WORK_STATE(INVALIDATE_OBJECT, "INVL", fscache_invalidate_object);
-static WORK_STATE(UPDATE_OBJECT, "UPDT", fscache_update_object);
-
-static WORK_STATE(LOOKUP_FAILURE, "LCFL", fscache_lookup_failure);
-static WORK_STATE(KILL_OBJECT, "KILL", fscache_kill_object);
-static WORK_STATE(KILL_DEPENDENTS, "KDEP", fscache_kill_dependents);
-static WORK_STATE(DROP_OBJECT, "DROP", fscache_drop_object);
-static WORK_STATE(OBJECT_DEAD, "DEAD", fscache_object_dead);
-
-static WAIT_STATE(WAIT_FOR_INIT, "?INI",
- TRANSIT_TO(INIT_OBJECT, 1 << FSCACHE_OBJECT_EV_NEW_CHILD));
-
-static WAIT_STATE(WAIT_FOR_PARENT, "?PRN",
- TRANSIT_TO(PARENT_READY, 1 << FSCACHE_OBJECT_EV_PARENT_READY));
-
-static WAIT_STATE(WAIT_FOR_CMD, "?CMD",
- TRANSIT_TO(INVALIDATE_OBJECT, 1 << FSCACHE_OBJECT_EV_INVALIDATE),
- TRANSIT_TO(UPDATE_OBJECT, 1 << FSCACHE_OBJECT_EV_UPDATE),
- TRANSIT_TO(JUMPSTART_DEPS, 1 << FSCACHE_OBJECT_EV_NEW_CHILD));
-
-static WAIT_STATE(WAIT_FOR_CLEARANCE, "?CLR",
- TRANSIT_TO(KILL_OBJECT, 1 << FSCACHE_OBJECT_EV_CLEARED));
-
-/*
- * Out-of-band event transition tables. These are for handling unexpected
- * events, such as an I/O error. If an OOB event occurs, the state machine
- * clears and disables the event and forces a transition to the nominated work
- * state (acurrently executing work states will complete first).
- *
- * In such a situation, object->state remembers the state the machine should
- * have been in/gone to and returning NO_TRANSIT returns to that.
- */
-static const struct fscache_transition fscache_osm_init_oob[] = {
- TRANSIT_TO(ABORT_INIT,
- (1 << FSCACHE_OBJECT_EV_ERROR) |
- (1 << FSCACHE_OBJECT_EV_KILL)),
- { 0, NULL }
-};
-
-static const struct fscache_transition fscache_osm_lookup_oob[] = {
- TRANSIT_TO(LOOKUP_FAILURE,
- (1 << FSCACHE_OBJECT_EV_ERROR) |
- (1 << FSCACHE_OBJECT_EV_KILL)),
- { 0, NULL }
-};
-
-static const struct fscache_transition fscache_osm_run_oob[] = {
- TRANSIT_TO(KILL_OBJECT,
- (1 << FSCACHE_OBJECT_EV_ERROR) |
- (1 << FSCACHE_OBJECT_EV_KILL)),
- { 0, NULL }
-};
-
-static int fscache_get_object(struct fscache_object *,
- enum fscache_obj_ref_trace);
-static void fscache_put_object(struct fscache_object *,
- enum fscache_obj_ref_trace);
-static bool fscache_enqueue_dependents(struct fscache_object *, int);
-static void fscache_dequeue_object(struct fscache_object *);
-static void fscache_update_aux_data(struct fscache_object *);
-
-/*
- * we need to notify the parent when an op completes that we had outstanding
- * upon it
- */
-static inline void fscache_done_parent_op(struct fscache_object *object)
-{
- struct fscache_object *parent = object->parent;
-
- _enter("OBJ%x {OBJ%x,%x}",
- object->debug_id, parent->debug_id, parent->n_ops);
-
- spin_lock_nested(&parent->lock, 1);
- parent->n_obj_ops--;
- parent->n_ops--;
- if (parent->n_ops == 0)
- fscache_raise_event(parent, FSCACHE_OBJECT_EV_CLEARED);
- spin_unlock(&parent->lock);
-}
-
-/*
- * Object state machine dispatcher.
- */
-static void fscache_object_sm_dispatcher(struct fscache_object *object)
-{
- const struct fscache_transition *t;
- const struct fscache_state *state, *new_state;
- unsigned long events, event_mask;
- bool oob;
- int event = -1;
-
- ASSERT(object != NULL);
-
- _enter("{OBJ%x,%s,%lx}",
- object->debug_id, object->state->name, object->events);
-
- event_mask = object->event_mask;
-restart:
- object->event_mask = 0; /* Mask normal event handling */
- state = object->state;
-restart_masked:
- events = object->events;
-
- /* Handle any out-of-band events (typically an error) */
- if (events & object->oob_event_mask) {
- _debug("{OBJ%x} oob %lx",
- object->debug_id, events & object->oob_event_mask);
- oob = true;
- for (t = object->oob_table; t->events; t++) {
- if (events & t->events) {
- state = t->transit_to;
- ASSERT(state->work != NULL);
- event = fls(events & t->events) - 1;
- __clear_bit(event, &object->oob_event_mask);
- clear_bit(event, &object->events);
- goto execute_work_state;
- }
- }
- }
- oob = false;
-
- /* Wait states are just transition tables */
- if (!state->work) {
- if (events & event_mask) {
- for (t = state->transitions; t->events; t++) {
- if (events & t->events) {
- new_state = t->transit_to;
- event = fls(events & t->events) - 1;
- trace_fscache_osm(object, state,
- true, false, event);
- clear_bit(event, &object->events);
- _debug("{OBJ%x} ev %d: %s -> %s",
- object->debug_id, event,
- state->name, new_state->name);
- object->state = state = new_state;
- goto execute_work_state;
- }
- }
-
- /* The event mask didn't include all the tabled bits */
- BUG();
- }
- /* Randomly woke up */
- goto unmask_events;
- }
-
-execute_work_state:
- _debug("{OBJ%x} exec %s", object->debug_id, state->name);
-
- trace_fscache_osm(object, state, false, oob, event);
- new_state = state->work(object, event);
- event = -1;
- if (new_state == NO_TRANSIT) {
- _debug("{OBJ%x} %s notrans", object->debug_id, state->name);
- if (unlikely(state == STATE(OBJECT_DEAD))) {
- _leave(" [dead]");
- return;
- }
- fscache_enqueue_object(object);
- event_mask = object->oob_event_mask;
- goto unmask_events;
- }
-
- _debug("{OBJ%x} %s -> %s",
- object->debug_id, state->name, new_state->name);
- object->state = state = new_state;
-
- if (state->work) {
- if (unlikely(state == STATE(OBJECT_DEAD))) {
- _leave(" [dead]");
- return;
- }
- goto restart_masked;
- }
-
- /* Transited to wait state */
- event_mask = object->oob_event_mask;
- for (t = state->transitions; t->events; t++)
- event_mask |= t->events;
-
-unmask_events:
- object->event_mask = event_mask;
- smp_mb();
- events = object->events;
- if (events & event_mask)
- goto restart;
- _leave(" [msk %lx]", event_mask);
-}
-
-/*
- * execute an object
- */
-static void fscache_object_work_func(struct work_struct *work)
-{
- struct fscache_object *object =
- container_of(work, struct fscache_object, work);
-
- _enter("{OBJ%x}", object->debug_id);
-
- fscache_object_sm_dispatcher(object);
- fscache_put_object(object, fscache_obj_put_work);
-}
-
-/**
- * fscache_object_init - Initialise a cache object description
- * @object: Object description
- * @cookie: Cookie object will be attached to
- * @cache: Cache in which backing object will be found
- *
- * Initialise a cache object description to its basic values.
- *
- * See Documentation/filesystems/caching/backend-api.rst for a complete
- * description.
- */
-void fscache_object_init(struct fscache_object *object,
- struct fscache_cookie *cookie,
- struct fscache_cache *cache)
-{
- const struct fscache_transition *t;
-
- atomic_inc(&cache->object_count);
-
- object->state = STATE(WAIT_FOR_INIT);
- object->oob_table = fscache_osm_init_oob;
- object->flags = 1 << FSCACHE_OBJECT_IS_LIVE;
- spin_lock_init(&object->lock);
- INIT_LIST_HEAD(&object->cache_link);
- INIT_HLIST_NODE(&object->cookie_link);
- INIT_WORK(&object->work, fscache_object_work_func);
- INIT_LIST_HEAD(&object->dependents);
- INIT_LIST_HEAD(&object->dep_link);
- INIT_LIST_HEAD(&object->pending_ops);
- object->n_children = 0;
- object->n_ops = object->n_in_progress = object->n_exclusive = 0;
- object->events = 0;
- object->store_limit = 0;
- object->store_limit_l = 0;
- object->cache = cache;
- object->cookie = cookie;
- fscache_cookie_get(cookie, fscache_cookie_get_attach_object);
- object->parent = NULL;
-#ifdef CONFIG_FSCACHE_OBJECT_LIST
- RB_CLEAR_NODE(&object->objlist_link);
-#endif
-
- object->oob_event_mask = 0;
- for (t = object->oob_table; t->events; t++)
- object->oob_event_mask |= t->events;
- object->event_mask = object->oob_event_mask;
- for (t = object->state->transitions; t->events; t++)
- object->event_mask |= t->events;
-}
-EXPORT_SYMBOL(fscache_object_init);
-
-/*
- * Mark the object as no longer being live, making sure that we synchronise
- * against op submission.
- */
-static inline void fscache_mark_object_dead(struct fscache_object *object)
-{
- spin_lock(&object->lock);
- clear_bit(FSCACHE_OBJECT_IS_LIVE, &object->flags);
- spin_unlock(&object->lock);
-}
-
-/*
- * Abort object initialisation before we start it.
- */
-static const struct fscache_state *fscache_abort_initialisation(struct fscache_object *object,
- int event)
-{
- _enter("{OBJ%x},%d", object->debug_id, event);
-
- object->oob_event_mask = 0;
- fscache_dequeue_object(object);
- return transit_to(KILL_OBJECT);
-}
-
-/*
- * initialise an object
- * - check the specified object's parent to see if we can make use of it
- * immediately to do a creation
- * - we may need to start the process of creating a parent and we need to wait
- * for the parent's lookup and creation to complete if it's not there yet
- */
-static const struct fscache_state *fscache_initialise_object(struct fscache_object *object,
- int event)
-{
- struct fscache_object *parent;
- bool success;
-
- _enter("{OBJ%x},%d", object->debug_id, event);
-
- ASSERT(list_empty(&object->dep_link));
-
- parent = object->parent;
- if (!parent) {
- _leave(" [no parent]");
- return transit_to(DROP_OBJECT);
- }
-
- _debug("parent: %s of:%lx", parent->state->name, parent->flags);
-
- if (fscache_object_is_dying(parent)) {
- _leave(" [bad parent]");
- return transit_to(DROP_OBJECT);
- }
-
- if (fscache_object_is_available(parent)) {
- _leave(" [ready]");
- return transit_to(PARENT_READY);
- }
-
- _debug("wait");
-
- spin_lock(&parent->lock);
- fscache_stat(&fscache_n_cop_grab_object);
- success = false;
- if (fscache_object_is_live(parent) &&
- object->cache->ops->grab_object(object, fscache_obj_get_add_to_deps)) {
- list_add(&object->dep_link, &parent->dependents);
- success = true;
- }
- fscache_stat_d(&fscache_n_cop_grab_object);
- spin_unlock(&parent->lock);
- if (!success) {
- _leave(" [grab failed]");
- return transit_to(DROP_OBJECT);
- }
-
- /* fscache_acquire_non_index_cookie() uses this
- * to wake the chain up */
- fscache_raise_event(parent, FSCACHE_OBJECT_EV_NEW_CHILD);
- _leave(" [wait]");
- return transit_to(WAIT_FOR_PARENT);
-}
-
-/*
- * Once the parent object is ready, we should kick off our lookup op.
- */
-static const struct fscache_state *fscache_parent_ready(struct fscache_object *object,
- int event)
-{
- struct fscache_object *parent = object->parent;
-
- _enter("{OBJ%x},%d", object->debug_id, event);
-
- ASSERT(parent != NULL);
-
- spin_lock(&parent->lock);
- parent->n_ops++;
- parent->n_obj_ops++;
- spin_unlock(&parent->lock);
-
- _leave("");
- return transit_to(LOOK_UP_OBJECT);
-}
-
-/*
- * look an object up in the cache from which it was allocated
- * - we hold an "access lock" on the parent object, so the parent object cannot
- * be withdrawn by either party till we've finished
- */
-static const struct fscache_state *fscache_look_up_object(struct fscache_object *object,
- int event)
-{
- struct fscache_cookie *cookie = object->cookie;
- struct fscache_object *parent = object->parent;
- int ret;
-
- _enter("{OBJ%x},%d", object->debug_id, event);
-
- object->oob_table = fscache_osm_lookup_oob;
-
- ASSERT(parent != NULL);
- ASSERTCMP(parent->n_ops, >, 0);
- ASSERTCMP(parent->n_obj_ops, >, 0);
-
- /* make sure the parent is still available */
- ASSERT(fscache_object_is_available(parent));
-
- if (fscache_object_is_dying(parent) ||
- test_bit(FSCACHE_IOERROR, &object->cache->flags) ||
- !fscache_use_cookie(object)) {
- _leave(" [unavailable]");
- return transit_to(LOOKUP_FAILURE);
- }
-
- _debug("LOOKUP \"%s\" in \"%s\"",
- cookie->def->name, object->cache->tag->name);
-
- fscache_stat(&fscache_n_object_lookups);
- fscache_stat(&fscache_n_cop_lookup_object);
- ret = object->cache->ops->lookup_object(object);
- fscache_stat_d(&fscache_n_cop_lookup_object);
-
- fscache_unuse_cookie(object);
-
- if (ret == -ETIMEDOUT) {
- /* probably stuck behind another object, so move this one to
- * the back of the queue */
- fscache_stat(&fscache_n_object_lookups_timed_out);
- _leave(" [timeout]");
- return NO_TRANSIT;
- }
-
- if (ret < 0) {
- _leave(" [error]");
- return transit_to(LOOKUP_FAILURE);
- }
-
- _leave(" [ok]");
- return transit_to(OBJECT_AVAILABLE);
-}
-
-/**
- * fscache_object_lookup_negative - Note negative cookie lookup
- * @object: Object pointing to cookie to mark
- *
- * Note negative lookup, permitting those waiting to read data from an already
- * existing backing object to continue as there's no data for them to read.
- */
-void fscache_object_lookup_negative(struct fscache_object *object)
-{
- struct fscache_cookie *cookie = object->cookie;
-
- _enter("{OBJ%x,%s}", object->debug_id, object->state->name);
-
- if (!test_and_set_bit(FSCACHE_OBJECT_IS_LOOKED_UP, &object->flags)) {
- fscache_stat(&fscache_n_object_lookups_negative);
-
- /* Allow write requests to begin stacking up and read requests to begin
- * returning ENODATA.
- */
- set_bit(FSCACHE_COOKIE_NO_DATA_YET, &cookie->flags);
- clear_bit(FSCACHE_COOKIE_UNAVAILABLE, &cookie->flags);
-
- clear_bit_unlock(FSCACHE_COOKIE_LOOKING_UP, &cookie->flags);
- wake_up_bit(&cookie->flags, FSCACHE_COOKIE_LOOKING_UP);
- }
- _leave("");
-}
-EXPORT_SYMBOL(fscache_object_lookup_negative);
-
-/**
- * fscache_obtained_object - Note successful object lookup or creation
- * @object: Object pointing to cookie to mark
- *
- * Note successful lookup and/or creation, permitting those waiting to write
- * data to a backing object to continue.
- *
- * Note that after calling this, an object's cookie may be relinquished by the
- * netfs, and so must be accessed with object lock held.
- */
-void fscache_obtained_object(struct fscache_object *object)
-{
- struct fscache_cookie *cookie = object->cookie;
-
- _enter("{OBJ%x,%s}", object->debug_id, object->state->name);
-
- /* if we were still looking up, then we must have a positive lookup
- * result, in which case there may be data available */
- if (!test_and_set_bit(FSCACHE_OBJECT_IS_LOOKED_UP, &object->flags)) {
- fscache_stat(&fscache_n_object_lookups_positive);
-
- /* We do (presumably) have data */
- clear_bit_unlock(FSCACHE_COOKIE_NO_DATA_YET, &cookie->flags);
- clear_bit(FSCACHE_COOKIE_UNAVAILABLE, &cookie->flags);
-
- /* Allow write requests to begin stacking up and read requests
- * to begin shovelling data.
- */
- clear_bit_unlock(FSCACHE_COOKIE_LOOKING_UP, &cookie->flags);
- wake_up_bit(&cookie->flags, FSCACHE_COOKIE_LOOKING_UP);
- } else {
- fscache_stat(&fscache_n_object_created);
- }
-
- set_bit(FSCACHE_OBJECT_IS_AVAILABLE, &object->flags);
- _leave("");
-}
-EXPORT_SYMBOL(fscache_obtained_object);
-
-/*
- * handle an object that has just become available
- */
-static const struct fscache_state *fscache_object_available(struct fscache_object *object,
- int event)
-{
- _enter("{OBJ%x},%d", object->debug_id, event);
-
- object->oob_table = fscache_osm_run_oob;
-
- spin_lock(&object->lock);
-
- fscache_done_parent_op(object);
- if (object->n_in_progress == 0) {
- if (object->n_ops > 0) {
- ASSERTCMP(object->n_ops, >=, object->n_obj_ops);
- fscache_start_operations(object);
- } else {
- ASSERT(list_empty(&object->pending_ops));
- }
- }
- spin_unlock(&object->lock);
-
- fscache_stat(&fscache_n_cop_lookup_complete);
- object->cache->ops->lookup_complete(object);
- fscache_stat_d(&fscache_n_cop_lookup_complete);
-
- fscache_stat(&fscache_n_object_avail);
-
- _leave("");
- return transit_to(JUMPSTART_DEPS);
-}
-
-/*
- * Wake up this object's dependent objects now that we've become available.
- */
-static const struct fscache_state *fscache_jumpstart_dependents(struct fscache_object *object,
- int event)
-{
- _enter("{OBJ%x},%d", object->debug_id, event);
-
- if (!fscache_enqueue_dependents(object, FSCACHE_OBJECT_EV_PARENT_READY))
- return NO_TRANSIT; /* Not finished; requeue */
- return transit_to(WAIT_FOR_CMD);
-}
-
-/*
- * Handle lookup or creation failute.
- */
-static const struct fscache_state *fscache_lookup_failure(struct fscache_object *object,
- int event)
-{
- struct fscache_cookie *cookie;
-
- _enter("{OBJ%x},%d", object->debug_id, event);
-
- object->oob_event_mask = 0;
-
- fscache_stat(&fscache_n_cop_lookup_complete);
- object->cache->ops->lookup_complete(object);
- fscache_stat_d(&fscache_n_cop_lookup_complete);
-
- set_bit(FSCACHE_OBJECT_KILLED_BY_CACHE, &object->flags);
-
- cookie = object->cookie;
- set_bit(FSCACHE_COOKIE_UNAVAILABLE, &cookie->flags);
- if (test_and_clear_bit(FSCACHE_COOKIE_LOOKING_UP, &cookie->flags))
- wake_up_bit(&cookie->flags, FSCACHE_COOKIE_LOOKING_UP);
-
- fscache_done_parent_op(object);
- return transit_to(KILL_OBJECT);
-}
-
-/*
- * Wait for completion of all active operations on this object and the death of
- * all child objects of this object.
- */
-static const struct fscache_state *fscache_kill_object(struct fscache_object *object,
- int event)
-{
- _enter("{OBJ%x,%d,%d},%d",
- object->debug_id, object->n_ops, object->n_children, event);
-
- fscache_mark_object_dead(object);
- object->oob_event_mask = 0;
-
- if (test_bit(FSCACHE_OBJECT_RETIRED, &object->flags)) {
- /* Reject any new read/write ops and abort any that are pending. */
- clear_bit(FSCACHE_OBJECT_PENDING_WRITE, &object->flags);
- fscache_cancel_all_ops(object);
- }
-
- if (list_empty(&object->dependents) &&
- object->n_ops == 0 &&
- object->n_children == 0)
- return transit_to(DROP_OBJECT);
-
- if (object->n_in_progress == 0) {
- spin_lock(&object->lock);
- if (object->n_ops > 0 && object->n_in_progress == 0)
- fscache_start_operations(object);
- spin_unlock(&object->lock);
- }
-
- if (!list_empty(&object->dependents))
- return transit_to(KILL_DEPENDENTS);
-
- return transit_to(WAIT_FOR_CLEARANCE);
-}
-
-/*
- * Kill dependent objects.
- */
-static const struct fscache_state *fscache_kill_dependents(struct fscache_object *object,
- int event)
-{
- _enter("{OBJ%x},%d", object->debug_id, event);
-
- if (!fscache_enqueue_dependents(object, FSCACHE_OBJECT_EV_KILL))
- return NO_TRANSIT; /* Not finished */
- return transit_to(WAIT_FOR_CLEARANCE);
-}
-
-/*
- * Drop an object's attachments
- */
-static const struct fscache_state *fscache_drop_object(struct fscache_object *object,
- int event)
-{
- struct fscache_object *parent = object->parent;
- struct fscache_cookie *cookie = object->cookie;
- struct fscache_cache *cache = object->cache;
- bool awaken = false;
-
- _enter("{OBJ%x,%d},%d", object->debug_id, object->n_children, event);
-
- ASSERT(cookie != NULL);
- ASSERT(!hlist_unhashed(&object->cookie_link));
-
- if (test_bit(FSCACHE_COOKIE_AUX_UPDATED, &cookie->flags)) {
- _debug("final update");
- fscache_update_aux_data(object);
- }
-
- /* Make sure the cookie no longer points here and that the netfs isn't
- * waiting for us.
- */
- spin_lock(&cookie->lock);
- hlist_del_init(&object->cookie_link);
- if (hlist_empty(&cookie->backing_objects) &&
- test_and_clear_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags))
- awaken = true;
- spin_unlock(&cookie->lock);
-
- if (awaken)
- wake_up_bit(&cookie->flags, FSCACHE_COOKIE_INVALIDATING);
- if (test_and_clear_bit(FSCACHE_COOKIE_LOOKING_UP, &cookie->flags))
- wake_up_bit(&cookie->flags, FSCACHE_COOKIE_LOOKING_UP);
-
-
- /* Prevent a race with our last child, which has to signal EV_CLEARED
- * before dropping our spinlock.
- */
- spin_lock(&object->lock);
- spin_unlock(&object->lock);
-
- /* Discard from the cache's collection of objects */
- spin_lock(&cache->object_list_lock);
- list_del_init(&object->cache_link);
- spin_unlock(&cache->object_list_lock);
-
- fscache_stat(&fscache_n_cop_drop_object);
- cache->ops->drop_object(object);
- fscache_stat_d(&fscache_n_cop_drop_object);
-
- /* The parent object wants to know when all it dependents have gone */
- if (parent) {
- _debug("release parent OBJ%x {%d}",
- parent->debug_id, parent->n_children);
-
- spin_lock(&parent->lock);
- parent->n_children--;
- if (parent->n_children == 0)
- fscache_raise_event(parent, FSCACHE_OBJECT_EV_CLEARED);
- spin_unlock(&parent->lock);
- object->parent = NULL;
- }
-
- /* this just shifts the object release to the work processor */
- fscache_put_object(object, fscache_obj_put_drop_obj);
- fscache_stat(&fscache_n_object_dead);
-
- _leave("");
- return transit_to(OBJECT_DEAD);
-}
-
-/*
- * get a ref on an object
- */
-static int fscache_get_object(struct fscache_object *object,
- enum fscache_obj_ref_trace why)
-{
- int ret;
-
- fscache_stat(&fscache_n_cop_grab_object);
- ret = object->cache->ops->grab_object(object, why) ? 0 : -EAGAIN;
- fscache_stat_d(&fscache_n_cop_grab_object);
- return ret;
-}
-
-/*
- * Discard a ref on an object
- */
-static void fscache_put_object(struct fscache_object *object,
- enum fscache_obj_ref_trace why)
-{
- fscache_stat(&fscache_n_cop_put_object);
- object->cache->ops->put_object(object, why);
- fscache_stat_d(&fscache_n_cop_put_object);
-}
-
-/**
- * fscache_object_destroy - Note that a cache object is about to be destroyed
- * @object: The object to be destroyed
- *
- * Note the imminent destruction and deallocation of a cache object record.
- */
-void fscache_object_destroy(struct fscache_object *object)
-{
- /* We can get rid of the cookie now */
- fscache_cookie_put(object->cookie, fscache_cookie_put_object);
- object->cookie = NULL;
-}
-EXPORT_SYMBOL(fscache_object_destroy);
-
-/*
- * enqueue an object for metadata-type processing
- */
-void fscache_enqueue_object(struct fscache_object *object)
-{
- _enter("{OBJ%x}", object->debug_id);
-
- if (fscache_get_object(object, fscache_obj_get_queue) >= 0) {
- wait_queue_head_t *cong_wq =
- &get_cpu_var(fscache_object_cong_wait);
-
- if (queue_work(fscache_object_wq, &object->work)) {
- if (fscache_object_congested())
- wake_up(cong_wq);
- } else
- fscache_put_object(object, fscache_obj_put_queue);
-
- put_cpu_var(fscache_object_cong_wait);
- }
-}
-
-/**
- * fscache_object_sleep_till_congested - Sleep until object wq is congested
- * @timeoutp: Scheduler sleep timeout
- *
- * Allow an object handler to sleep until the object workqueue is congested.
- *
- * The caller must set up a wake up event before calling this and must have set
- * the appropriate sleep mode (such as TASK_UNINTERRUPTIBLE) and tested its own
- * condition before calling this function as no test is made here.
- *
- * %true is returned if the object wq is congested, %false otherwise.
- */
-bool fscache_object_sleep_till_congested(signed long *timeoutp)
-{
- wait_queue_head_t *cong_wq = this_cpu_ptr(&fscache_object_cong_wait);
- DEFINE_WAIT(wait);
-
- if (fscache_object_congested())
- return true;
-
- add_wait_queue_exclusive(cong_wq, &wait);
- if (!fscache_object_congested())
- *timeoutp = schedule_timeout(*timeoutp);
- finish_wait(cong_wq, &wait);
-
- return fscache_object_congested();
-}
-EXPORT_SYMBOL_GPL(fscache_object_sleep_till_congested);
-
-/*
- * Enqueue the dependents of an object for metadata-type processing.
- *
- * If we don't manage to finish the list before the scheduler wants to run
- * again then return false immediately. We return true if the list was
- * cleared.
- */
-static bool fscache_enqueue_dependents(struct fscache_object *object, int event)
-{
- struct fscache_object *dep;
- bool ret = true;
-
- _enter("{OBJ%x}", object->debug_id);
-
- if (list_empty(&object->dependents))
- return true;
-
- spin_lock(&object->lock);
-
- while (!list_empty(&object->dependents)) {
- dep = list_entry(object->dependents.next,
- struct fscache_object, dep_link);
- list_del_init(&dep->dep_link);
-
- fscache_raise_event(dep, event);
- fscache_put_object(dep, fscache_obj_put_enq_dep);
-
- if (!list_empty(&object->dependents) && need_resched()) {
- ret = false;
- break;
- }
- }
-
- spin_unlock(&object->lock);
- return ret;
-}
-
-/*
- * remove an object from whatever queue it's waiting on
- */
-static void fscache_dequeue_object(struct fscache_object *object)
-{
- _enter("{OBJ%x}", object->debug_id);
-
- if (!list_empty(&object->dep_link)) {
- spin_lock(&object->parent->lock);
- list_del_init(&object->dep_link);
- spin_unlock(&object->parent->lock);
- }
-
- _leave("");
-}
-
-/**
- * fscache_check_aux - Ask the netfs whether an object on disk is still valid
- * @object: The object to ask about
- * @data: The auxiliary data for the object
- * @datalen: The size of the auxiliary data
- * @object_size: The size of the object according to the server.
- *
- * This function consults the netfs about the coherency state of an object.
- * The caller must be holding a ref on cookie->n_active (held by
- * fscache_look_up_object() on behalf of the cache backend during object lookup
- * and creation).
- */
-enum fscache_checkaux fscache_check_aux(struct fscache_object *object,
- const void *data, uint16_t datalen,
- loff_t object_size)
-{
- enum fscache_checkaux result;
-
- if (!object->cookie->def->check_aux) {
- fscache_stat(&fscache_n_checkaux_none);
- return FSCACHE_CHECKAUX_OKAY;
- }
-
- result = object->cookie->def->check_aux(object->cookie->netfs_data,
- data, datalen, object_size);
- switch (result) {
- /* entry okay as is */
- case FSCACHE_CHECKAUX_OKAY:
- fscache_stat(&fscache_n_checkaux_okay);
- break;
-
- /* entry requires update */
- case FSCACHE_CHECKAUX_NEEDS_UPDATE:
- fscache_stat(&fscache_n_checkaux_update);
- break;
-
- /* entry requires deletion */
- case FSCACHE_CHECKAUX_OBSOLETE:
- fscache_stat(&fscache_n_checkaux_obsolete);
- break;
-
- default:
- BUG();
- }
-
- return result;
-}
-EXPORT_SYMBOL(fscache_check_aux);
-
-/*
- * Asynchronously invalidate an object.
- */
-static const struct fscache_state *_fscache_invalidate_object(struct fscache_object *object,
- int event)
-{
- struct fscache_operation *op;
- struct fscache_cookie *cookie = object->cookie;
-
- _enter("{OBJ%x},%d", object->debug_id, event);
-
- /* We're going to need the cookie. If the cookie is not available then
- * retire the object instead.
- */
- if (!fscache_use_cookie(object)) {
- ASSERT(radix_tree_empty(&object->cookie->stores));
- set_bit(FSCACHE_OBJECT_RETIRED, &object->flags);
- _leave(" [no cookie]");
- return transit_to(KILL_OBJECT);
- }
-
- /* Reject any new read/write ops and abort any that are pending. */
- fscache_invalidate_writes(cookie);
- clear_bit(FSCACHE_OBJECT_PENDING_WRITE, &object->flags);
- fscache_cancel_all_ops(object);
-
- /* Now we have to wait for in-progress reads and writes */
- op = kzalloc(sizeof(*op), GFP_KERNEL);
- if (!op)
- goto nomem;
-
- fscache_operation_init(cookie, op, object->cache->ops->invalidate_object,
- NULL, NULL);
- op->flags = FSCACHE_OP_ASYNC |
- (1 << FSCACHE_OP_EXCLUSIVE) |
- (1 << FSCACHE_OP_UNUSE_COOKIE);
- trace_fscache_page_op(cookie, NULL, op, fscache_page_op_invalidate);
-
- spin_lock(&cookie->lock);
- if (fscache_submit_exclusive_op(object, op) < 0)
- goto submit_op_failed;
- spin_unlock(&cookie->lock);
- fscache_put_operation(op);
-
- /* Once we've completed the invalidation, we know there will be no data
- * stored in the cache and thus we can reinstate the data-check-skip
- * optimisation.
- */
- set_bit(FSCACHE_COOKIE_NO_DATA_YET, &cookie->flags);
-
- /* We can allow read and write requests to come in once again. They'll
- * queue up behind our exclusive invalidation operation.
- */
- if (test_and_clear_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags))
- wake_up_bit(&cookie->flags, FSCACHE_COOKIE_INVALIDATING);
- _leave(" [ok]");
- return transit_to(UPDATE_OBJECT);
-
-nomem:
- fscache_mark_object_dead(object);
- fscache_unuse_cookie(object);
- _leave(" [ENOMEM]");
- return transit_to(KILL_OBJECT);
-
-submit_op_failed:
- fscache_mark_object_dead(object);
- spin_unlock(&cookie->lock);
- fscache_unuse_cookie(object);
- kfree(op);
- _leave(" [EIO]");
- return transit_to(KILL_OBJECT);
-}
-
-static const struct fscache_state *fscache_invalidate_object(struct fscache_object *object,
- int event)
-{
- const struct fscache_state *s;
-
- fscache_stat(&fscache_n_invalidates_run);
- fscache_stat(&fscache_n_cop_invalidate_object);
- s = _fscache_invalidate_object(object, event);
- fscache_stat_d(&fscache_n_cop_invalidate_object);
- return s;
-}
-
-/*
- * Update auxiliary data.
- */
-static void fscache_update_aux_data(struct fscache_object *object)
-{
- fscache_stat(&fscache_n_updates_run);
- fscache_stat(&fscache_n_cop_update_object);
- object->cache->ops->update_object(object);
- fscache_stat_d(&fscache_n_cop_update_object);
-}
-
-/*
- * Asynchronously update an object.
- */
-static const struct fscache_state *fscache_update_object(struct fscache_object *object,
- int event)
-{
- _enter("{OBJ%x},%d", object->debug_id, event);
-
- fscache_update_aux_data(object);
-
- _leave("");
- return transit_to(WAIT_FOR_CMD);
-}
-
-/**
- * fscache_object_retrying_stale - Note retrying stale object
- * @object: The object that will be retried
- *
- * Note that an object lookup found an on-disk object that was adjudged to be
- * stale and has been deleted. The lookup will be retried.
- */
-void fscache_object_retrying_stale(struct fscache_object *object)
-{
- fscache_stat(&fscache_n_cache_no_space_reject);
-}
-EXPORT_SYMBOL(fscache_object_retrying_stale);
-
-/**
- * fscache_object_mark_killed - Note that an object was killed
- * @object: The object that was culled
- * @why: The reason the object was killed.
- *
- * Note that an object was killed. Returns true if the object was
- * already marked killed, false if it wasn't.
- */
-void fscache_object_mark_killed(struct fscache_object *object,
- enum fscache_why_object_killed why)
-{
- if (test_and_set_bit(FSCACHE_OBJECT_KILLED_BY_CACHE, &object->flags)) {
- pr_err("Error: Object already killed by cache [%s]\n",
- object->cache->identifier);
- return;
- }
-
- switch (why) {
- case FSCACHE_OBJECT_NO_SPACE:
- fscache_stat(&fscache_n_cache_no_space_reject);
- break;
- case FSCACHE_OBJECT_IS_STALE:
- fscache_stat(&fscache_n_cache_stale_objects);
- break;
- case FSCACHE_OBJECT_WAS_RETIRED:
- fscache_stat(&fscache_n_cache_retired_objects);
- break;
- case FSCACHE_OBJECT_WAS_CULLED:
- fscache_stat(&fscache_n_cache_culled_objects);
- break;
- }
-}
-EXPORT_SYMBOL(fscache_object_mark_killed);
-
-/*
- * The object is dead. We can get here if an object gets queued by an event
- * that would lead to its death (such as EV_KILL) when the dispatcher is
- * already running (and so can be requeued) but hasn't yet cleared the event
- * mask.
- */
-static const struct fscache_state *fscache_object_dead(struct fscache_object *object,
- int event)
-{
- if (!test_and_set_bit(FSCACHE_OBJECT_RUN_AFTER_DEAD,
- &object->flags))
- return NO_TRANSIT;
-
- WARN(true, "FS-Cache object redispatched after death");
- return NO_TRANSIT;
-}
+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* FS-Cache worker operation management routines
- *
- * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- *
- * See Documentation/filesystems/caching/operations.rst
- */
-
-#define FSCACHE_DEBUG_LEVEL OPERATION
-#include <linux/module.h>
-#include <linux/seq_file.h>
-#include <linux/slab.h>
-#include "internal.h"
-
-atomic_t fscache_op_debug_id;
-EXPORT_SYMBOL(fscache_op_debug_id);
-
-static void fscache_operation_dummy_cancel(struct fscache_operation *op)
-{
-}
-
-/**
- * fscache_operation_init - Do basic initialisation of an operation
- * @cookie: The cookie to operate on
- * @op: The operation to initialise
- * @processor: The function to perform the operation
- * @cancel: A function to handle operation cancellation
- * @release: The release function to assign
- *
- * Do basic initialisation of an operation. The caller must still set flags,
- * object and processor if needed.
- */
-void fscache_operation_init(struct fscache_cookie *cookie,
- struct fscache_operation *op,
- fscache_operation_processor_t processor,
- fscache_operation_cancel_t cancel,
- fscache_operation_release_t release)
-{
- INIT_WORK(&op->work, fscache_op_work_func);
- atomic_set(&op->usage, 1);
- op->state = FSCACHE_OP_ST_INITIALISED;
- op->debug_id = atomic_inc_return(&fscache_op_debug_id);
- op->processor = processor;
- op->cancel = cancel ?: fscache_operation_dummy_cancel;
- op->release = release;
- INIT_LIST_HEAD(&op->pend_link);
- fscache_stat(&fscache_n_op_initialised);
- trace_fscache_op(cookie, op, fscache_op_init);
-}
-EXPORT_SYMBOL(fscache_operation_init);
-
-/**
- * fscache_enqueue_operation - Enqueue an operation for processing
- * @op: The operation to enqueue
- *
- * Enqueue an operation for processing by the FS-Cache thread pool.
- *
- * This will get its own ref on the object.
- */
-void fscache_enqueue_operation(struct fscache_operation *op)
-{
- struct fscache_cookie *cookie = op->object->cookie;
-
- _enter("{OBJ%x OP%x,%u}",
- op->object->debug_id, op->debug_id, atomic_read(&op->usage));
-
- ASSERT(list_empty(&op->pend_link));
- ASSERT(op->processor != NULL);
- ASSERT(fscache_object_is_available(op->object));
- ASSERTCMP(atomic_read(&op->usage), >, 0);
- ASSERTIFCMP(op->state != FSCACHE_OP_ST_IN_PROGRESS,
- op->state, ==, FSCACHE_OP_ST_CANCELLED);
-
- fscache_stat(&fscache_n_op_enqueue);
- switch (op->flags & FSCACHE_OP_TYPE) {
- case FSCACHE_OP_ASYNC:
- trace_fscache_op(cookie, op, fscache_op_enqueue_async);
- _debug("queue async");
- atomic_inc(&op->usage);
- if (!queue_work(fscache_op_wq, &op->work))
- fscache_put_operation(op);
- break;
- case FSCACHE_OP_MYTHREAD:
- trace_fscache_op(cookie, op, fscache_op_enqueue_mythread);
- _debug("queue for caller's attention");
- break;
- default:
- pr_err("Unexpected op type %lx", op->flags);
- BUG();
- break;
- }
-}
-EXPORT_SYMBOL(fscache_enqueue_operation);
-
-/*
- * start an op running
- */
-static void fscache_run_op(struct fscache_object *object,
- struct fscache_operation *op)
-{
- ASSERTCMP(op->state, ==, FSCACHE_OP_ST_PENDING);
-
- op->state = FSCACHE_OP_ST_IN_PROGRESS;
- object->n_in_progress++;
- if (test_and_clear_bit(FSCACHE_OP_WAITING, &op->flags))
- wake_up_bit(&op->flags, FSCACHE_OP_WAITING);
- if (op->processor)
- fscache_enqueue_operation(op);
- else
- trace_fscache_op(object->cookie, op, fscache_op_run);
- fscache_stat(&fscache_n_op_run);
-}
-
-/*
- * report an unexpected submission
- */
-static void fscache_report_unexpected_submission(struct fscache_object *object,
- struct fscache_operation *op,
- const struct fscache_state *ostate)
-{
- static bool once_only;
- struct fscache_operation *p;
- unsigned n;
-
- if (once_only)
- return;
- once_only = true;
-
- kdebug("unexpected submission OP%x [OBJ%x %s]",
- op->debug_id, object->debug_id, object->state->name);
- kdebug("objstate=%s [%s]", object->state->name, ostate->name);
- kdebug("objflags=%lx", object->flags);
- kdebug("objevent=%lx [%lx]", object->events, object->event_mask);
- kdebug("ops=%u inp=%u exc=%u",
- object->n_ops, object->n_in_progress, object->n_exclusive);
-
- if (!list_empty(&object->pending_ops)) {
- n = 0;
- list_for_each_entry(p, &object->pending_ops, pend_link) {
- ASSERTCMP(p->object, ==, object);
- kdebug("%p %p", op->processor, op->release);
- n++;
- }
-
- kdebug("n=%u", n);
- }
-
- dump_stack();
-}
-
-/*
- * submit an exclusive operation for an object
- * - other ops are excluded from running simultaneously with this one
- * - this gets any extra refs it needs on an op
- */
-int fscache_submit_exclusive_op(struct fscache_object *object,
- struct fscache_operation *op)
-{
- const struct fscache_state *ostate;
- unsigned long flags;
- int ret;
-
- _enter("{OBJ%x OP%x},", object->debug_id, op->debug_id);
-
- trace_fscache_op(object->cookie, op, fscache_op_submit_ex);
-
- ASSERTCMP(op->state, ==, FSCACHE_OP_ST_INITIALISED);
- ASSERTCMP(atomic_read(&op->usage), >, 0);
-
- spin_lock(&object->lock);
- ASSERTCMP(object->n_ops, >=, object->n_in_progress);
- ASSERTCMP(object->n_ops, >=, object->n_exclusive);
- ASSERT(list_empty(&op->pend_link));
-
- ostate = object->state;
- smp_rmb();
-
- op->state = FSCACHE_OP_ST_PENDING;
- flags = READ_ONCE(object->flags);
- if (unlikely(!(flags & BIT(FSCACHE_OBJECT_IS_LIVE)))) {
- fscache_stat(&fscache_n_op_rejected);
- op->cancel(op);
- op->state = FSCACHE_OP_ST_CANCELLED;
- ret = -ENOBUFS;
- } else if (unlikely(fscache_cache_is_broken(object))) {
- op->cancel(op);
- op->state = FSCACHE_OP_ST_CANCELLED;
- ret = -EIO;
- } else if (flags & BIT(FSCACHE_OBJECT_IS_AVAILABLE)) {
- op->object = object;
- object->n_ops++;
- object->n_exclusive++; /* reads and writes must wait */
-
- if (object->n_in_progress > 0) {
- atomic_inc(&op->usage);
- list_add_tail(&op->pend_link, &object->pending_ops);
- fscache_stat(&fscache_n_op_pend);
- } else if (!list_empty(&object->pending_ops)) {
- atomic_inc(&op->usage);
- list_add_tail(&op->pend_link, &object->pending_ops);
- fscache_stat(&fscache_n_op_pend);
- fscache_start_operations(object);
- } else {
- ASSERTCMP(object->n_in_progress, ==, 0);
- fscache_run_op(object, op);
- }
-
- /* need to issue a new write op after this */
- clear_bit(FSCACHE_OBJECT_PENDING_WRITE, &object->flags);
- ret = 0;
- } else if (flags & BIT(FSCACHE_OBJECT_IS_LOOKED_UP)) {
- op->object = object;
- object->n_ops++;
- object->n_exclusive++; /* reads and writes must wait */
- atomic_inc(&op->usage);
- list_add_tail(&op->pend_link, &object->pending_ops);
- fscache_stat(&fscache_n_op_pend);
- ret = 0;
- } else if (flags & BIT(FSCACHE_OBJECT_KILLED_BY_CACHE)) {
- op->cancel(op);
- op->state = FSCACHE_OP_ST_CANCELLED;
- ret = -ENOBUFS;
- } else {
- fscache_report_unexpected_submission(object, op, ostate);
- op->cancel(op);
- op->state = FSCACHE_OP_ST_CANCELLED;
- ret = -ENOBUFS;
- }
-
- spin_unlock(&object->lock);
- return ret;
-}
-
-/*
- * submit an operation for an object
- * - objects may be submitted only in the following states:
- * - during object creation (write ops may be submitted)
- * - whilst the object is active
- * - after an I/O error incurred in one of the two above states (op rejected)
- * - this gets any extra refs it needs on an op
- */
-int fscache_submit_op(struct fscache_object *object,
- struct fscache_operation *op)
-{
- const struct fscache_state *ostate;
- unsigned long flags;
- int ret;
-
- _enter("{OBJ%x OP%x},{%u}",
- object->debug_id, op->debug_id, atomic_read(&op->usage));
-
- trace_fscache_op(object->cookie, op, fscache_op_submit);
-
- ASSERTCMP(op->state, ==, FSCACHE_OP_ST_INITIALISED);
- ASSERTCMP(atomic_read(&op->usage), >, 0);
-
- spin_lock(&object->lock);
- ASSERTCMP(object->n_ops, >=, object->n_in_progress);
- ASSERTCMP(object->n_ops, >=, object->n_exclusive);
- ASSERT(list_empty(&op->pend_link));
-
- ostate = object->state;
- smp_rmb();
-
- op->state = FSCACHE_OP_ST_PENDING;
- flags = READ_ONCE(object->flags);
- if (unlikely(!(flags & BIT(FSCACHE_OBJECT_IS_LIVE)))) {
- fscache_stat(&fscache_n_op_rejected);
- op->cancel(op);
- op->state = FSCACHE_OP_ST_CANCELLED;
- ret = -ENOBUFS;
- } else if (unlikely(fscache_cache_is_broken(object))) {
- op->cancel(op);
- op->state = FSCACHE_OP_ST_CANCELLED;
- ret = -EIO;
- } else if (flags & BIT(FSCACHE_OBJECT_IS_AVAILABLE)) {
- op->object = object;
- object->n_ops++;
-
- if (object->n_exclusive > 0) {
- atomic_inc(&op->usage);
- list_add_tail(&op->pend_link, &object->pending_ops);
- fscache_stat(&fscache_n_op_pend);
- } else if (!list_empty(&object->pending_ops)) {
- atomic_inc(&op->usage);
- list_add_tail(&op->pend_link, &object->pending_ops);
- fscache_stat(&fscache_n_op_pend);
- fscache_start_operations(object);
- } else {
- ASSERTCMP(object->n_exclusive, ==, 0);
- fscache_run_op(object, op);
- }
- ret = 0;
- } else if (flags & BIT(FSCACHE_OBJECT_IS_LOOKED_UP)) {
- op->object = object;
- object->n_ops++;
- atomic_inc(&op->usage);
- list_add_tail(&op->pend_link, &object->pending_ops);
- fscache_stat(&fscache_n_op_pend);
- ret = 0;
- } else if (flags & BIT(FSCACHE_OBJECT_KILLED_BY_CACHE)) {
- op->cancel(op);
- op->state = FSCACHE_OP_ST_CANCELLED;
- ret = -ENOBUFS;
- } else {
- fscache_report_unexpected_submission(object, op, ostate);
- ASSERT(!fscache_object_is_active(object));
- op->cancel(op);
- op->state = FSCACHE_OP_ST_CANCELLED;
- ret = -ENOBUFS;
- }
-
- spin_unlock(&object->lock);
- return ret;
-}
-
-/*
- * queue an object for withdrawal on error, aborting all following asynchronous
- * operations
- */
-void fscache_abort_object(struct fscache_object *object)
-{
- _enter("{OBJ%x}", object->debug_id);
-
- fscache_raise_event(object, FSCACHE_OBJECT_EV_ERROR);
-}
-
-/*
- * Jump start the operation processing on an object. The caller must hold
- * object->lock.
- */
-void fscache_start_operations(struct fscache_object *object)
-{
- struct fscache_operation *op;
- bool stop = false;
-
- while (!list_empty(&object->pending_ops) && !stop) {
- op = list_entry(object->pending_ops.next,
- struct fscache_operation, pend_link);
-
- if (test_bit(FSCACHE_OP_EXCLUSIVE, &op->flags)) {
- if (object->n_in_progress > 0)
- break;
- stop = true;
- }
- list_del_init(&op->pend_link);
- fscache_run_op(object, op);
-
- /* the pending queue was holding a ref on the object */
- fscache_put_operation(op);
- }
-
- ASSERTCMP(object->n_in_progress, <=, object->n_ops);
-
- _debug("woke %d ops on OBJ%x",
- object->n_in_progress, object->debug_id);
-}
-
-/*
- * cancel an operation that's pending on an object
- */
-int fscache_cancel_op(struct fscache_operation *op,
- bool cancel_in_progress_op)
-{
- struct fscache_object *object = op->object;
- bool put = false;
- int ret;
-
- _enter("OBJ%x OP%x}", op->object->debug_id, op->debug_id);
-
- trace_fscache_op(object->cookie, op, fscache_op_cancel);
-
- ASSERTCMP(op->state, >=, FSCACHE_OP_ST_PENDING);
- ASSERTCMP(op->state, !=, FSCACHE_OP_ST_CANCELLED);
- ASSERTCMP(atomic_read(&op->usage), >, 0);
-
- spin_lock(&object->lock);
-
- ret = -EBUSY;
- if (op->state == FSCACHE_OP_ST_PENDING) {
- ASSERT(!list_empty(&op->pend_link));
- list_del_init(&op->pend_link);
- put = true;
-
- fscache_stat(&fscache_n_op_cancelled);
- op->cancel(op);
- op->state = FSCACHE_OP_ST_CANCELLED;
- if (test_bit(FSCACHE_OP_EXCLUSIVE, &op->flags))
- object->n_exclusive--;
- if (test_and_clear_bit(FSCACHE_OP_WAITING, &op->flags))
- wake_up_bit(&op->flags, FSCACHE_OP_WAITING);
- ret = 0;
- } else if (op->state == FSCACHE_OP_ST_IN_PROGRESS && cancel_in_progress_op) {
- ASSERTCMP(object->n_in_progress, >, 0);
- if (test_bit(FSCACHE_OP_EXCLUSIVE, &op->flags))
- object->n_exclusive--;
- object->n_in_progress--;
- if (object->n_in_progress == 0)
- fscache_start_operations(object);
-
- fscache_stat(&fscache_n_op_cancelled);
- op->cancel(op);
- op->state = FSCACHE_OP_ST_CANCELLED;
- if (test_bit(FSCACHE_OP_EXCLUSIVE, &op->flags))
- object->n_exclusive--;
- if (test_and_clear_bit(FSCACHE_OP_WAITING, &op->flags))
- wake_up_bit(&op->flags, FSCACHE_OP_WAITING);
- ret = 0;
- }
-
- if (put)
- fscache_put_operation(op);
- spin_unlock(&object->lock);
- _leave(" = %d", ret);
- return ret;
-}
-
-/*
- * Cancel all pending operations on an object
- */
-void fscache_cancel_all_ops(struct fscache_object *object)
-{
- struct fscache_operation *op;
-
- _enter("OBJ%x", object->debug_id);
-
- spin_lock(&object->lock);
-
- while (!list_empty(&object->pending_ops)) {
- op = list_entry(object->pending_ops.next,
- struct fscache_operation, pend_link);
- fscache_stat(&fscache_n_op_cancelled);
- list_del_init(&op->pend_link);
-
- trace_fscache_op(object->cookie, op, fscache_op_cancel_all);
-
- ASSERTCMP(op->state, ==, FSCACHE_OP_ST_PENDING);
- op->cancel(op);
- op->state = FSCACHE_OP_ST_CANCELLED;
-
- if (test_bit(FSCACHE_OP_EXCLUSIVE, &op->flags))
- object->n_exclusive--;
- if (test_and_clear_bit(FSCACHE_OP_WAITING, &op->flags))
- wake_up_bit(&op->flags, FSCACHE_OP_WAITING);
- fscache_put_operation(op);
- cond_resched_lock(&object->lock);
- }
-
- spin_unlock(&object->lock);
- _leave("");
-}
-
-/*
- * Record the completion or cancellation of an in-progress operation.
- */
-void fscache_op_complete(struct fscache_operation *op, bool cancelled)
-{
- struct fscache_object *object = op->object;
-
- _enter("OBJ%x", object->debug_id);
-
- ASSERTCMP(op->state, ==, FSCACHE_OP_ST_IN_PROGRESS);
- ASSERTCMP(object->n_in_progress, >, 0);
- ASSERTIFCMP(test_bit(FSCACHE_OP_EXCLUSIVE, &op->flags),
- object->n_exclusive, >, 0);
- ASSERTIFCMP(test_bit(FSCACHE_OP_EXCLUSIVE, &op->flags),
- object->n_in_progress, ==, 1);
-
- spin_lock(&object->lock);
-
- if (!cancelled) {
- trace_fscache_op(object->cookie, op, fscache_op_completed);
- op->state = FSCACHE_OP_ST_COMPLETE;
- } else {
- op->cancel(op);
- trace_fscache_op(object->cookie, op, fscache_op_cancelled);
- op->state = FSCACHE_OP_ST_CANCELLED;
- }
-
- if (test_bit(FSCACHE_OP_EXCLUSIVE, &op->flags))
- object->n_exclusive--;
- object->n_in_progress--;
- if (object->n_in_progress == 0)
- fscache_start_operations(object);
-
- spin_unlock(&object->lock);
- _leave("");
-}
-EXPORT_SYMBOL(fscache_op_complete);
-
-/*
- * release an operation
- * - queues pending ops if this is the last in-progress op
- */
-void fscache_put_operation(struct fscache_operation *op)
-{
- struct fscache_object *object;
- struct fscache_cache *cache;
-
- _enter("{OBJ%x OP%x,%d}",
- op->object ? op->object->debug_id : 0,
- op->debug_id, atomic_read(&op->usage));
-
- ASSERTCMP(atomic_read(&op->usage), >, 0);
-
- if (!atomic_dec_and_test(&op->usage))
- return;
-
- trace_fscache_op(op->object ? op->object->cookie : NULL, op, fscache_op_put);
-
- _debug("PUT OP");
- ASSERTIFCMP(op->state != FSCACHE_OP_ST_INITIALISED &&
- op->state != FSCACHE_OP_ST_COMPLETE,
- op->state, ==, FSCACHE_OP_ST_CANCELLED);
-
- fscache_stat(&fscache_n_op_release);
-
- if (op->release) {
- op->release(op);
- op->release = NULL;
- }
- op->state = FSCACHE_OP_ST_DEAD;
-
- object = op->object;
- if (likely(object)) {
- if (test_bit(FSCACHE_OP_DEC_READ_CNT, &op->flags))
- atomic_dec(&object->n_reads);
- if (test_bit(FSCACHE_OP_UNUSE_COOKIE, &op->flags))
- fscache_unuse_cookie(object);
-
- /* now... we may get called with the object spinlock held, so we
- * complete the cleanup here only if we can immediately acquire the
- * lock, and defer it otherwise */
- if (!spin_trylock(&object->lock)) {
- _debug("defer put");
- fscache_stat(&fscache_n_op_deferred_release);
-
- cache = object->cache;
- spin_lock(&cache->op_gc_list_lock);
- list_add_tail(&op->pend_link, &cache->op_gc_list);
- spin_unlock(&cache->op_gc_list_lock);
- schedule_work(&cache->op_gc);
- _leave(" [defer]");
- return;
- }
-
- ASSERTCMP(object->n_ops, >, 0);
- object->n_ops--;
- if (object->n_ops == 0)
- fscache_raise_event(object, FSCACHE_OBJECT_EV_CLEARED);
-
- spin_unlock(&object->lock);
- }
-
- kfree(op);
- _leave(" [done]");
-}
-EXPORT_SYMBOL(fscache_put_operation);
-
-/*
- * garbage collect operations that have had their release deferred
- */
-void fscache_operation_gc(struct work_struct *work)
-{
- struct fscache_operation *op;
- struct fscache_object *object;
- struct fscache_cache *cache =
- container_of(work, struct fscache_cache, op_gc);
- int count = 0;
-
- _enter("");
-
- do {
- spin_lock(&cache->op_gc_list_lock);
- if (list_empty(&cache->op_gc_list)) {
- spin_unlock(&cache->op_gc_list_lock);
- break;
- }
-
- op = list_entry(cache->op_gc_list.next,
- struct fscache_operation, pend_link);
- list_del(&op->pend_link);
- spin_unlock(&cache->op_gc_list_lock);
-
- object = op->object;
- trace_fscache_op(object->cookie, op, fscache_op_gc);
-
- spin_lock(&object->lock);
-
- _debug("GC DEFERRED REL OBJ%x OP%x",
- object->debug_id, op->debug_id);
- fscache_stat(&fscache_n_op_gc);
-
- ASSERTCMP(atomic_read(&op->usage), ==, 0);
- ASSERTCMP(op->state, ==, FSCACHE_OP_ST_DEAD);
-
- ASSERTCMP(object->n_ops, >, 0);
- object->n_ops--;
- if (object->n_ops == 0)
- fscache_raise_event(object, FSCACHE_OBJECT_EV_CLEARED);
-
- spin_unlock(&object->lock);
- kfree(op);
-
- } while (count++ < 20);
-
- if (!list_empty(&cache->op_gc_list))
- schedule_work(&cache->op_gc);
-
- _leave("");
-}
-
-/*
- * execute an operation using fs_op_wq to provide processing context -
- * the caller holds a ref to this object, so we don't need to hold one
- */
-void fscache_op_work_func(struct work_struct *work)
-{
- struct fscache_operation *op =
- container_of(work, struct fscache_operation, work);
-
- _enter("{OBJ%x OP%x,%d}",
- op->object->debug_id, op->debug_id, atomic_read(&op->usage));
-
- trace_fscache_op(op->object->cookie, op, fscache_op_work);
-
- ASSERT(op->processor != NULL);
- op->processor(op);
- fscache_put_operation(op);
-
- _leave("");
-}
+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* Cache page management and data I/O routines
- *
- * Copyright (C) 2004-2008 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- */
-
-#define FSCACHE_DEBUG_LEVEL PAGE
-#include <linux/module.h>
-#include <linux/fscache-cache.h>
-#include <linux/buffer_head.h>
-#include <linux/pagevec.h>
-#include <linux/slab.h>
-#include "internal.h"
-
-/*
- * check to see if a page is being written to the cache
- */
-bool __fscache_check_page_write(struct fscache_cookie *cookie, struct page *page)
-{
- void *val;
-
- rcu_read_lock();
- val = radix_tree_lookup(&cookie->stores, page->index);
- rcu_read_unlock();
- trace_fscache_check_page(cookie, page, val, 0);
-
- return val != NULL;
-}
-EXPORT_SYMBOL(__fscache_check_page_write);
-
-/*
- * wait for a page to finish being written to the cache
- */
-void __fscache_wait_on_page_write(struct fscache_cookie *cookie, struct page *page)
-{
- wait_queue_head_t *wq = bit_waitqueue(&cookie->flags, 0);
-
- trace_fscache_page(cookie, page, fscache_page_write_wait);
-
- wait_event(*wq, !__fscache_check_page_write(cookie, page));
-}
-EXPORT_SYMBOL(__fscache_wait_on_page_write);
-
-/*
- * wait for a page to finish being written to the cache. Put a timeout here
- * since we might be called recursively via parent fs.
- */
-static
-bool release_page_wait_timeout(struct fscache_cookie *cookie, struct page *page)
-{
- wait_queue_head_t *wq = bit_waitqueue(&cookie->flags, 0);
-
- return wait_event_timeout(*wq, !__fscache_check_page_write(cookie, page),
- HZ);
-}
-
-/*
- * decide whether a page can be released, possibly by cancelling a store to it
- * - we're allowed to sleep if __GFP_DIRECT_RECLAIM is flagged
- */
-bool __fscache_maybe_release_page(struct fscache_cookie *cookie,
- struct page *page,
- gfp_t gfp)
-{
- struct page *xpage;
- void *val;
-
- _enter("%p,%p,%x", cookie, page, gfp);
-
- trace_fscache_page(cookie, page, fscache_page_maybe_release);
-
-try_again:
- rcu_read_lock();
- val = radix_tree_lookup(&cookie->stores, page->index);
- if (!val) {
- rcu_read_unlock();
- fscache_stat(&fscache_n_store_vmscan_not_storing);
- __fscache_uncache_page(cookie, page);
- return true;
- }
-
- /* see if the page is actually undergoing storage - if so we can't get
- * rid of it till the cache has finished with it */
- if (radix_tree_tag_get(&cookie->stores, page->index,
- FSCACHE_COOKIE_STORING_TAG)) {
- rcu_read_unlock();
- goto page_busy;
- }
-
- /* the page is pending storage, so we attempt to cancel the store and
- * discard the store request so that the page can be reclaimed */
- spin_lock(&cookie->stores_lock);
- rcu_read_unlock();
-
- if (radix_tree_tag_get(&cookie->stores, page->index,
- FSCACHE_COOKIE_STORING_TAG)) {
- /* the page started to undergo storage whilst we were looking,
- * so now we can only wait or return */
- spin_unlock(&cookie->stores_lock);
- goto page_busy;
- }
-
- xpage = radix_tree_delete(&cookie->stores, page->index);
- trace_fscache_page(cookie, page, fscache_page_radix_delete);
- spin_unlock(&cookie->stores_lock);
-
- if (xpage) {
- fscache_stat(&fscache_n_store_vmscan_cancelled);
- fscache_stat(&fscache_n_store_radix_deletes);
- ASSERTCMP(xpage, ==, page);
- } else {
- fscache_stat(&fscache_n_store_vmscan_gone);
- }
-
- wake_up_bit(&cookie->flags, 0);
- trace_fscache_wake_cookie(cookie);
- if (xpage)
- put_page(xpage);
- __fscache_uncache_page(cookie, page);
- return true;
-
-page_busy:
- /* We will wait here if we're allowed to, but that could deadlock the
- * allocator as the work threads writing to the cache may all end up
- * sleeping on memory allocation, so we may need to impose a timeout
- * too. */
- if (!(gfp & __GFP_DIRECT_RECLAIM) || !(gfp & __GFP_FS)) {
- fscache_stat(&fscache_n_store_vmscan_busy);
- return false;
- }
-
- fscache_stat(&fscache_n_store_vmscan_wait);
- if (!release_page_wait_timeout(cookie, page))
- _debug("fscache writeout timeout page: %p{%lx}",
- page, page->index);
-
- gfp &= ~__GFP_DIRECT_RECLAIM;
- goto try_again;
-}
-EXPORT_SYMBOL(__fscache_maybe_release_page);
-
-/*
- * note that a page has finished being written to the cache
- */
-static void fscache_end_page_write(struct fscache_object *object,
- struct page *page)
-{
- struct fscache_cookie *cookie;
- struct page *xpage = NULL, *val;
-
- spin_lock(&object->lock);
- cookie = object->cookie;
- if (cookie) {
- /* delete the page from the tree if it is now no longer
- * pending */
- spin_lock(&cookie->stores_lock);
- radix_tree_tag_clear(&cookie->stores, page->index,
- FSCACHE_COOKIE_STORING_TAG);
- trace_fscache_page(cookie, page, fscache_page_radix_clear_store);
- if (!radix_tree_tag_get(&cookie->stores, page->index,
- FSCACHE_COOKIE_PENDING_TAG)) {
- fscache_stat(&fscache_n_store_radix_deletes);
- xpage = radix_tree_delete(&cookie->stores, page->index);
- trace_fscache_page(cookie, page, fscache_page_radix_delete);
- trace_fscache_page(cookie, page, fscache_page_write_end);
-
- val = radix_tree_lookup(&cookie->stores, page->index);
- trace_fscache_check_page(cookie, page, val, 1);
- } else {
- trace_fscache_page(cookie, page, fscache_page_write_end_pend);
- }
- spin_unlock(&cookie->stores_lock);
- wake_up_bit(&cookie->flags, 0);
- trace_fscache_wake_cookie(cookie);
- } else {
- trace_fscache_page(cookie, page, fscache_page_write_end_noc);
- }
- spin_unlock(&object->lock);
- if (xpage)
- put_page(xpage);
-}
-
-/*
- * actually apply the changed attributes to a cache object
- */
-static void fscache_attr_changed_op(struct fscache_operation *op)
-{
- struct fscache_object *object = op->object;
- int ret;
-
- _enter("{OBJ%x OP%x}", object->debug_id, op->debug_id);
-
- fscache_stat(&fscache_n_attr_changed_calls);
-
- if (fscache_object_is_active(object)) {
- fscache_stat(&fscache_n_cop_attr_changed);
- ret = object->cache->ops->attr_changed(object);
- fscache_stat_d(&fscache_n_cop_attr_changed);
- if (ret < 0)
- fscache_abort_object(object);
- fscache_op_complete(op, ret < 0);
- } else {
- fscache_op_complete(op, true);
- }
-
- _leave("");
-}
-
-/*
- * notification that the attributes on an object have changed
- */
-int __fscache_attr_changed(struct fscache_cookie *cookie)
-{
- struct fscache_operation *op;
- struct fscache_object *object;
- bool wake_cookie = false;
-
- _enter("%p", cookie);
-
- ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX);
-
- fscache_stat(&fscache_n_attr_changed);
-
- op = kzalloc(sizeof(*op), GFP_KERNEL);
- if (!op) {
- fscache_stat(&fscache_n_attr_changed_nomem);
- _leave(" = -ENOMEM");
- return -ENOMEM;
- }
-
- fscache_operation_init(cookie, op, fscache_attr_changed_op, NULL, NULL);
- trace_fscache_page_op(cookie, NULL, op, fscache_page_op_attr_changed);
- op->flags = FSCACHE_OP_ASYNC |
- (1 << FSCACHE_OP_EXCLUSIVE) |
- (1 << FSCACHE_OP_UNUSE_COOKIE);
-
- spin_lock(&cookie->lock);
-
- if (!fscache_cookie_enabled(cookie) ||
- hlist_empty(&cookie->backing_objects))
- goto nobufs;
- object = hlist_entry(cookie->backing_objects.first,
- struct fscache_object, cookie_link);
-
- __fscache_use_cookie(cookie);
- if (fscache_submit_exclusive_op(object, op) < 0)
- goto nobufs_dec;
- spin_unlock(&cookie->lock);
- fscache_stat(&fscache_n_attr_changed_ok);
- fscache_put_operation(op);
- _leave(" = 0");
- return 0;
-
-nobufs_dec:
- wake_cookie = __fscache_unuse_cookie(cookie);
-nobufs:
- spin_unlock(&cookie->lock);
- fscache_put_operation(op);
- if (wake_cookie)
- __fscache_wake_unused_cookie(cookie);
- fscache_stat(&fscache_n_attr_changed_nobufs);
- _leave(" = %d", -ENOBUFS);
- return -ENOBUFS;
-}
-EXPORT_SYMBOL(__fscache_attr_changed);
-
-/*
- * Handle cancellation of a pending retrieval op
- */
-static void fscache_do_cancel_retrieval(struct fscache_operation *_op)
-{
- struct fscache_retrieval *op =
- container_of(_op, struct fscache_retrieval, op);
-
- atomic_set(&op->n_pages, 0);
-}
-
-/*
- * release a retrieval op reference
- */
-static void fscache_release_retrieval_op(struct fscache_operation *_op)
-{
- struct fscache_retrieval *op =
- container_of(_op, struct fscache_retrieval, op);
-
- _enter("{OP%x}", op->op.debug_id);
-
- ASSERTIFCMP(op->op.state != FSCACHE_OP_ST_INITIALISED,
- atomic_read(&op->n_pages), ==, 0);
-
- if (op->context)
- fscache_put_context(op->cookie, op->context);
-
- _leave("");
-}
-
-/*
- * allocate a retrieval op
- */
-struct fscache_retrieval *fscache_alloc_retrieval(
- struct fscache_cookie *cookie,
- struct address_space *mapping,
- fscache_rw_complete_t end_io_func,
- void *context)
-{
- struct fscache_retrieval *op;
-
- /* allocate a retrieval operation and attempt to submit it */
- op = kzalloc(sizeof(*op), GFP_NOIO);
- if (!op) {
- fscache_stat(&fscache_n_retrievals_nomem);
- return NULL;
- }
-
- fscache_operation_init(cookie, &op->op, NULL,
- fscache_do_cancel_retrieval,
- fscache_release_retrieval_op);
- op->op.flags = FSCACHE_OP_MYTHREAD |
- (1UL << FSCACHE_OP_WAITING) |
- (1UL << FSCACHE_OP_UNUSE_COOKIE);
- op->cookie = cookie;
- op->mapping = mapping;
- op->end_io_func = end_io_func;
- op->context = context;
- INIT_LIST_HEAD(&op->to_do);
-
- /* Pin the netfs read context in case we need to do the actual netfs
- * read because we've encountered a cache read failure.
- */
- if (context)
- fscache_get_context(op->cookie, context);
- return op;
-}
-
-/*
- * wait for a deferred lookup to complete
- */
-int fscache_wait_for_deferred_lookup(struct fscache_cookie *cookie)
-{
- _enter("");
-
- if (!test_bit(FSCACHE_COOKIE_LOOKING_UP, &cookie->flags)) {
- _leave(" = 0 [imm]");
- return 0;
- }
-
- fscache_stat(&fscache_n_retrievals_wait);
-
- if (wait_on_bit(&cookie->flags, FSCACHE_COOKIE_LOOKING_UP,
- TASK_INTERRUPTIBLE) != 0) {
- fscache_stat(&fscache_n_retrievals_intr);
- _leave(" = -ERESTARTSYS");
- return -ERESTARTSYS;
- }
-
- ASSERT(!test_bit(FSCACHE_COOKIE_LOOKING_UP, &cookie->flags));
-
- smp_rmb();
- _leave(" = 0 [dly]");
- return 0;
-}
-
-/*
- * wait for an object to become active (or dead)
- */
-int fscache_wait_for_operation_activation(struct fscache_object *object,
- struct fscache_operation *op,
- atomic_t *stat_op_waits,
- atomic_t *stat_object_dead)
-{
- int ret;
-
- if (!test_bit(FSCACHE_OP_WAITING, &op->flags))
- goto check_if_dead;
-
- _debug(">>> WT");
- if (stat_op_waits)
- fscache_stat(stat_op_waits);
- if (wait_on_bit(&op->flags, FSCACHE_OP_WAITING,
- TASK_INTERRUPTIBLE) != 0) {
- trace_fscache_op(object->cookie, op, fscache_op_signal);
- ret = fscache_cancel_op(op, false);
- if (ret == 0)
- return -ERESTARTSYS;
-
- /* it's been removed from the pending queue by another party,
- * so we should get to run shortly */
- wait_on_bit(&op->flags, FSCACHE_OP_WAITING,
- TASK_UNINTERRUPTIBLE);
- }
- _debug("<<< GO");
-
-check_if_dead:
- if (op->state == FSCACHE_OP_ST_CANCELLED) {
- if (stat_object_dead)
- fscache_stat(stat_object_dead);
- _leave(" = -ENOBUFS [cancelled]");
- return -ENOBUFS;
- }
- if (unlikely(fscache_object_is_dying(object) ||
- fscache_cache_is_broken(object))) {
- enum fscache_operation_state state = op->state;
- trace_fscache_op(object->cookie, op, fscache_op_signal);
- fscache_cancel_op(op, true);
- if (stat_object_dead)
- fscache_stat(stat_object_dead);
- _leave(" = -ENOBUFS [obj dead %d]", state);
- return -ENOBUFS;
- }
- return 0;
-}
-
-/*
- * read a page from the cache or allocate a block in which to store it
- * - we return:
- * -ENOMEM - out of memory, nothing done
- * -ERESTARTSYS - interrupted
- * -ENOBUFS - no backing object available in which to cache the block
- * -ENODATA - no data available in the backing object for this block
- * 0 - dispatched a read - it'll call end_io_func() when finished
- */
-int __fscache_read_or_alloc_page(struct fscache_cookie *cookie,
- struct page *page,
- fscache_rw_complete_t end_io_func,
- void *context,
- gfp_t gfp)
-{
- struct fscache_retrieval *op;
- struct fscache_object *object;
- bool wake_cookie = false;
- int ret;
-
- _enter("%p,%p,,,", cookie, page);
-
- fscache_stat(&fscache_n_retrievals);
-
- if (hlist_empty(&cookie->backing_objects))
- goto nobufs;
-
- if (test_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags)) {
- _leave(" = -ENOBUFS [invalidating]");
- return -ENOBUFS;
- }
-
- ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX);
- ASSERTCMP(page, !=, NULL);
-
- if (fscache_wait_for_deferred_lookup(cookie) < 0)
- return -ERESTARTSYS;
-
- op = fscache_alloc_retrieval(cookie, page->mapping,
- end_io_func, context);
- if (!op) {
- _leave(" = -ENOMEM");
- return -ENOMEM;
- }
- atomic_set(&op->n_pages, 1);
- trace_fscache_page_op(cookie, page, &op->op, fscache_page_op_retr_one);
-
- spin_lock(&cookie->lock);
-
- if (!fscache_cookie_enabled(cookie) ||
- hlist_empty(&cookie->backing_objects))
- goto nobufs_unlock;
- object = hlist_entry(cookie->backing_objects.first,
- struct fscache_object, cookie_link);
-
- ASSERT(test_bit(FSCACHE_OBJECT_IS_LOOKED_UP, &object->flags));
-
- __fscache_use_cookie(cookie);
- atomic_inc(&object->n_reads);
- __set_bit(FSCACHE_OP_DEC_READ_CNT, &op->op.flags);
-
- if (fscache_submit_op(object, &op->op) < 0)
- goto nobufs_unlock_dec;
- spin_unlock(&cookie->lock);
-
- fscache_stat(&fscache_n_retrieval_ops);
-
- /* we wait for the operation to become active, and then process it
- * *here*, in this thread, and not in the thread pool */
- ret = fscache_wait_for_operation_activation(
- object, &op->op,
- __fscache_stat(&fscache_n_retrieval_op_waits),
- __fscache_stat(&fscache_n_retrievals_object_dead));
- if (ret < 0)
- goto error;
-
- /* ask the cache to honour the operation */
- if (test_bit(FSCACHE_COOKIE_NO_DATA_YET, &object->cookie->flags)) {
- fscache_stat(&fscache_n_cop_allocate_page);
- ret = object->cache->ops->allocate_page(op, page, gfp);
- fscache_stat_d(&fscache_n_cop_allocate_page);
- if (ret == 0)
- ret = -ENODATA;
- } else {
- fscache_stat(&fscache_n_cop_read_or_alloc_page);
- ret = object->cache->ops->read_or_alloc_page(op, page, gfp);
- fscache_stat_d(&fscache_n_cop_read_or_alloc_page);
- }
-
-error:
- if (ret == -ENOMEM)
- fscache_stat(&fscache_n_retrievals_nomem);
- else if (ret == -ERESTARTSYS)
- fscache_stat(&fscache_n_retrievals_intr);
- else if (ret == -ENODATA)
- fscache_stat(&fscache_n_retrievals_nodata);
- else if (ret < 0)
- fscache_stat(&fscache_n_retrievals_nobufs);
- else
- fscache_stat(&fscache_n_retrievals_ok);
-
- fscache_put_retrieval(op);
- _leave(" = %d", ret);
- return ret;
-
-nobufs_unlock_dec:
- atomic_dec(&object->n_reads);
- wake_cookie = __fscache_unuse_cookie(cookie);
-nobufs_unlock:
- spin_unlock(&cookie->lock);
- if (wake_cookie)
- __fscache_wake_unused_cookie(cookie);
- fscache_put_retrieval(op);
-nobufs:
- fscache_stat(&fscache_n_retrievals_nobufs);
- _leave(" = -ENOBUFS");
- return -ENOBUFS;
-}
-EXPORT_SYMBOL(__fscache_read_or_alloc_page);
-
-/*
- * read a list of page from the cache or allocate a block in which to store
- * them
- * - we return:
- * -ENOMEM - out of memory, some pages may be being read
- * -ERESTARTSYS - interrupted, some pages may be being read
- * -ENOBUFS - no backing object or space available in which to cache any
- * pages not being read
- * -ENODATA - no data available in the backing object for some or all of
- * the pages
- * 0 - dispatched a read on all pages
- *
- * end_io_func() will be called for each page read from the cache as it is
- * finishes being read
- *
- * any pages for which a read is dispatched will be removed from pages and
- * nr_pages
- */
-int __fscache_read_or_alloc_pages(struct fscache_cookie *cookie,
- struct address_space *mapping,
- struct list_head *pages,
- unsigned *nr_pages,
- fscache_rw_complete_t end_io_func,
- void *context,
- gfp_t gfp)
-{
- struct fscache_retrieval *op;
- struct fscache_object *object;
- bool wake_cookie = false;
- int ret;
-
- _enter("%p,,%d,,,", cookie, *nr_pages);
-
- fscache_stat(&fscache_n_retrievals);
-
- if (hlist_empty(&cookie->backing_objects))
- goto nobufs;
-
- if (test_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags)) {
- _leave(" = -ENOBUFS [invalidating]");
- return -ENOBUFS;
- }
-
- ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX);
- ASSERTCMP(*nr_pages, >, 0);
- ASSERT(!list_empty(pages));
-
- if (fscache_wait_for_deferred_lookup(cookie) < 0)
- return -ERESTARTSYS;
-
- op = fscache_alloc_retrieval(cookie, mapping, end_io_func, context);
- if (!op)
- return -ENOMEM;
- atomic_set(&op->n_pages, *nr_pages);
- trace_fscache_page_op(cookie, NULL, &op->op, fscache_page_op_retr_multi);
-
- spin_lock(&cookie->lock);
-
- if (!fscache_cookie_enabled(cookie) ||
- hlist_empty(&cookie->backing_objects))
- goto nobufs_unlock;
- object = hlist_entry(cookie->backing_objects.first,
- struct fscache_object, cookie_link);
-
- __fscache_use_cookie(cookie);
- atomic_inc(&object->n_reads);
- __set_bit(FSCACHE_OP_DEC_READ_CNT, &op->op.flags);
-
- if (fscache_submit_op(object, &op->op) < 0)
- goto nobufs_unlock_dec;
- spin_unlock(&cookie->lock);
-
- fscache_stat(&fscache_n_retrieval_ops);
-
- /* we wait for the operation to become active, and then process it
- * *here*, in this thread, and not in the thread pool */
- ret = fscache_wait_for_operation_activation(
- object, &op->op,
- __fscache_stat(&fscache_n_retrieval_op_waits),
- __fscache_stat(&fscache_n_retrievals_object_dead));
- if (ret < 0)
- goto error;
-
- /* ask the cache to honour the operation */
- if (test_bit(FSCACHE_COOKIE_NO_DATA_YET, &object->cookie->flags)) {
- fscache_stat(&fscache_n_cop_allocate_pages);
- ret = object->cache->ops->allocate_pages(
- op, pages, nr_pages, gfp);
- fscache_stat_d(&fscache_n_cop_allocate_pages);
- } else {
- fscache_stat(&fscache_n_cop_read_or_alloc_pages);
- ret = object->cache->ops->read_or_alloc_pages(
- op, pages, nr_pages, gfp);
- fscache_stat_d(&fscache_n_cop_read_or_alloc_pages);
- }
-
-error:
- if (ret == -ENOMEM)
- fscache_stat(&fscache_n_retrievals_nomem);
- else if (ret == -ERESTARTSYS)
- fscache_stat(&fscache_n_retrievals_intr);
- else if (ret == -ENODATA)
- fscache_stat(&fscache_n_retrievals_nodata);
- else if (ret < 0)
- fscache_stat(&fscache_n_retrievals_nobufs);
- else
- fscache_stat(&fscache_n_retrievals_ok);
-
- fscache_put_retrieval(op);
- _leave(" = %d", ret);
- return ret;
-
-nobufs_unlock_dec:
- atomic_dec(&object->n_reads);
- wake_cookie = __fscache_unuse_cookie(cookie);
-nobufs_unlock:
- spin_unlock(&cookie->lock);
- fscache_put_retrieval(op);
- if (wake_cookie)
- __fscache_wake_unused_cookie(cookie);
-nobufs:
- fscache_stat(&fscache_n_retrievals_nobufs);
- _leave(" = -ENOBUFS");
- return -ENOBUFS;
-}
-EXPORT_SYMBOL(__fscache_read_or_alloc_pages);
-
-/*
- * allocate a block in the cache on which to store a page
- * - we return:
- * -ENOMEM - out of memory, nothing done
- * -ERESTARTSYS - interrupted
- * -ENOBUFS - no backing object available in which to cache the block
- * 0 - block allocated
- */
-int __fscache_alloc_page(struct fscache_cookie *cookie,
- struct page *page,
- gfp_t gfp)
-{
- struct fscache_retrieval *op;
- struct fscache_object *object;
- bool wake_cookie = false;
- int ret;
-
- _enter("%p,%p,,,", cookie, page);
-
- fscache_stat(&fscache_n_allocs);
-
- if (hlist_empty(&cookie->backing_objects))
- goto nobufs;
-
- ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX);
- ASSERTCMP(page, !=, NULL);
-
- if (test_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags)) {
- _leave(" = -ENOBUFS [invalidating]");
- return -ENOBUFS;
- }
-
- if (fscache_wait_for_deferred_lookup(cookie) < 0)
- return -ERESTARTSYS;
-
- op = fscache_alloc_retrieval(cookie, page->mapping, NULL, NULL);
- if (!op)
- return -ENOMEM;
- atomic_set(&op->n_pages, 1);
- trace_fscache_page_op(cookie, page, &op->op, fscache_page_op_alloc_one);
-
- spin_lock(&cookie->lock);
-
- if (!fscache_cookie_enabled(cookie) ||
- hlist_empty(&cookie->backing_objects))
- goto nobufs_unlock;
- object = hlist_entry(cookie->backing_objects.first,
- struct fscache_object, cookie_link);
-
- __fscache_use_cookie(cookie);
- if (fscache_submit_op(object, &op->op) < 0)
- goto nobufs_unlock_dec;
- spin_unlock(&cookie->lock);
-
- fscache_stat(&fscache_n_alloc_ops);
-
- ret = fscache_wait_for_operation_activation(
- object, &op->op,
- __fscache_stat(&fscache_n_alloc_op_waits),
- __fscache_stat(&fscache_n_allocs_object_dead));
- if (ret < 0)
- goto error;
-
- /* ask the cache to honour the operation */
- fscache_stat(&fscache_n_cop_allocate_page);
- ret = object->cache->ops->allocate_page(op, page, gfp);
- fscache_stat_d(&fscache_n_cop_allocate_page);
-
-error:
- if (ret == -ERESTARTSYS)
- fscache_stat(&fscache_n_allocs_intr);
- else if (ret < 0)
- fscache_stat(&fscache_n_allocs_nobufs);
- else
- fscache_stat(&fscache_n_allocs_ok);
-
- fscache_put_retrieval(op);
- _leave(" = %d", ret);
- return ret;
-
-nobufs_unlock_dec:
- wake_cookie = __fscache_unuse_cookie(cookie);
-nobufs_unlock:
- spin_unlock(&cookie->lock);
- fscache_put_retrieval(op);
- if (wake_cookie)
- __fscache_wake_unused_cookie(cookie);
-nobufs:
- fscache_stat(&fscache_n_allocs_nobufs);
- _leave(" = -ENOBUFS");
- return -ENOBUFS;
-}
-EXPORT_SYMBOL(__fscache_alloc_page);
-
-/*
- * Unmark pages allocate in the readahead code path (via:
- * fscache_readpages_or_alloc) after delegating to the base filesystem
- */
-void __fscache_readpages_cancel(struct fscache_cookie *cookie,
- struct list_head *pages)
-{
- struct page *page;
-
- list_for_each_entry(page, pages, lru) {
- if (PageFsCache(page))
- __fscache_uncache_page(cookie, page);
- }
-}
-EXPORT_SYMBOL(__fscache_readpages_cancel);
-
-/*
- * release a write op reference
- */
-static void fscache_release_write_op(struct fscache_operation *_op)
-{
- _enter("{OP%x}", _op->debug_id);
-}
-
-/*
- * perform the background storage of a page into the cache
- */
-static void fscache_write_op(struct fscache_operation *_op)
-{
- struct fscache_storage *op =
- container_of(_op, struct fscache_storage, op);
- struct fscache_object *object = op->op.object;
- struct fscache_cookie *cookie;
- struct page *page;
- unsigned n;
- void *results[1];
- int ret;
-
- _enter("{OP%x,%d}", op->op.debug_id, atomic_read(&op->op.usage));
-
-again:
- spin_lock(&object->lock);
- cookie = object->cookie;
-
- if (!fscache_object_is_active(object)) {
- /* If we get here, then the on-disk cache object likely no
- * longer exists, so we should just cancel this write
- * operation.
- */
- spin_unlock(&object->lock);
- fscache_op_complete(&op->op, true);
- _leave(" [inactive]");
- return;
- }
-
- if (!cookie) {
- /* If we get here, then the cookie belonging to the object was
- * detached, probably by the cookie being withdrawn due to
- * memory pressure, which means that the pages we might write
- * to the cache from no longer exist - therefore, we can just
- * cancel this write operation.
- */
- spin_unlock(&object->lock);
- fscache_op_complete(&op->op, true);
- _leave(" [cancel] op{f=%lx s=%u} obj{s=%s f=%lx}",
- _op->flags, _op->state, object->state->short_name,
- object->flags);
- return;
- }
-
- spin_lock(&cookie->stores_lock);
-
- fscache_stat(&fscache_n_store_calls);
-
- /* find a page to store */
- results[0] = NULL;
- page = NULL;
- n = radix_tree_gang_lookup_tag(&cookie->stores, results, 0, 1,
- FSCACHE_COOKIE_PENDING_TAG);
- trace_fscache_gang_lookup(cookie, &op->op, results, n, op->store_limit);
- if (n != 1)
- goto superseded;
- page = results[0];
- _debug("gang %d [%lx]", n, page->index);
-
- radix_tree_tag_set(&cookie->stores, page->index,
- FSCACHE_COOKIE_STORING_TAG);
- radix_tree_tag_clear(&cookie->stores, page->index,
- FSCACHE_COOKIE_PENDING_TAG);
- trace_fscache_page(cookie, page, fscache_page_radix_pend2store);
-
- spin_unlock(&cookie->stores_lock);
- spin_unlock(&object->lock);
-
- if (page->index >= op->store_limit)
- goto discard_page;
-
- fscache_stat(&fscache_n_store_pages);
- fscache_stat(&fscache_n_cop_write_page);
- ret = object->cache->ops->write_page(op, page);
- fscache_stat_d(&fscache_n_cop_write_page);
- trace_fscache_wrote_page(cookie, page, &op->op, ret);
- fscache_end_page_write(object, page);
- if (ret < 0) {
- fscache_abort_object(object);
- fscache_op_complete(&op->op, true);
- } else {
- fscache_enqueue_operation(&op->op);
- }
-
- _leave("");
- return;
-
-discard_page:
- fscache_stat(&fscache_n_store_pages_over_limit);
- trace_fscache_wrote_page(cookie, page, &op->op, -ENOBUFS);
- fscache_end_page_write(object, page);
- goto again;
-
-superseded:
- /* this writer is going away and there aren't any more things to
- * write */
- _debug("cease");
- spin_unlock(&cookie->stores_lock);
- clear_bit(FSCACHE_OBJECT_PENDING_WRITE, &object->flags);
- spin_unlock(&object->lock);
- fscache_op_complete(&op->op, false);
- _leave("");
-}
-
-/*
- * Clear the pages pending writing for invalidation
- */
-void fscache_invalidate_writes(struct fscache_cookie *cookie)
-{
- struct page *page;
- void *results[16];
- int n, i;
-
- _enter("");
-
- for (;;) {
- spin_lock(&cookie->stores_lock);
- n = radix_tree_gang_lookup_tag(&cookie->stores, results, 0,
- ARRAY_SIZE(results),
- FSCACHE_COOKIE_PENDING_TAG);
- if (n == 0) {
- spin_unlock(&cookie->stores_lock);
- break;
- }
-
- for (i = n - 1; i >= 0; i--) {
- page = results[i];
- radix_tree_delete(&cookie->stores, page->index);
- trace_fscache_page(cookie, page, fscache_page_radix_delete);
- trace_fscache_page(cookie, page, fscache_page_inval);
- }
-
- spin_unlock(&cookie->stores_lock);
-
- for (i = n - 1; i >= 0; i--)
- put_page(results[i]);
- }
-
- wake_up_bit(&cookie->flags, 0);
- trace_fscache_wake_cookie(cookie);
-
- _leave("");
-}
-
-/*
- * request a page be stored in the cache
- * - returns:
- * -ENOMEM - out of memory, nothing done
- * -ENOBUFS - no backing object available in which to cache the page
- * 0 - dispatched a write - it'll call end_io_func() when finished
- *
- * if the cookie still has a backing object at this point, that object can be
- * in one of a few states with respect to storage processing:
- *
- * (1) negative lookup, object not yet created (FSCACHE_COOKIE_CREATING is
- * set)
- *
- * (a) no writes yet
- *
- * (b) writes deferred till post-creation (mark page for writing and
- * return immediately)
- *
- * (2) negative lookup, object created, initial fill being made from netfs
- *
- * (a) fill point not yet reached this page (mark page for writing and
- * return)
- *
- * (b) fill point passed this page (queue op to store this page)
- *
- * (3) object extant (queue op to store this page)
- *
- * any other state is invalid
- */
-int __fscache_write_page(struct fscache_cookie *cookie,
- struct page *page,
- loff_t object_size,
- gfp_t gfp)
-{
- struct fscache_storage *op;
- struct fscache_object *object;
- bool wake_cookie = false;
- int ret;
-
- _enter("%p,%x,", cookie, (u32) page->flags);
-
- ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX);
- ASSERT(PageFsCache(page));
-
- fscache_stat(&fscache_n_stores);
-
- if (test_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags)) {
- _leave(" = -ENOBUFS [invalidating]");
- return -ENOBUFS;
- }
-
- op = kzalloc(sizeof(*op), GFP_NOIO | __GFP_NOMEMALLOC | __GFP_NORETRY);
- if (!op)
- goto nomem;
-
- fscache_operation_init(cookie, &op->op, fscache_write_op, NULL,
- fscache_release_write_op);
- op->op.flags = FSCACHE_OP_ASYNC |
- (1 << FSCACHE_OP_WAITING) |
- (1 << FSCACHE_OP_UNUSE_COOKIE);
-
- ret = radix_tree_maybe_preload(gfp & ~__GFP_HIGHMEM);
- if (ret < 0)
- goto nomem_free;
-
- trace_fscache_page_op(cookie, page, &op->op, fscache_page_op_write_one);
-
- ret = -ENOBUFS;
- spin_lock(&cookie->lock);
-
- if (!fscache_cookie_enabled(cookie) ||
- hlist_empty(&cookie->backing_objects))
- goto nobufs;
- object = hlist_entry(cookie->backing_objects.first,
- struct fscache_object, cookie_link);
- if (test_bit(FSCACHE_IOERROR, &object->cache->flags))
- goto nobufs;
-
- trace_fscache_page(cookie, page, fscache_page_write);
-
- /* add the page to the pending-storage radix tree on the backing
- * object */
- spin_lock(&object->lock);
-
- if (object->store_limit_l != object_size)
- fscache_set_store_limit(object, object_size);
-
- spin_lock(&cookie->stores_lock);
-
- _debug("store limit %llx", (unsigned long long) object->store_limit);
-
- ret = radix_tree_insert(&cookie->stores, page->index, page);
- if (ret < 0) {
- if (ret == -EEXIST)
- goto already_queued;
- _debug("insert failed %d", ret);
- goto nobufs_unlock_obj;
- }
-
- trace_fscache_page(cookie, page, fscache_page_radix_insert);
- radix_tree_tag_set(&cookie->stores, page->index,
- FSCACHE_COOKIE_PENDING_TAG);
- trace_fscache_page(cookie, page, fscache_page_radix_set_pend);
- get_page(page);
-
- /* we only want one writer at a time, but we do need to queue new
- * writers after exclusive ops */
- if (test_and_set_bit(FSCACHE_OBJECT_PENDING_WRITE, &object->flags))
- goto already_pending;
-
- spin_unlock(&cookie->stores_lock);
- spin_unlock(&object->lock);
-
- op->op.debug_id = atomic_inc_return(&fscache_op_debug_id);
- op->store_limit = object->store_limit;
-
- __fscache_use_cookie(cookie);
- if (fscache_submit_op(object, &op->op) < 0)
- goto submit_failed;
-
- spin_unlock(&cookie->lock);
- radix_tree_preload_end();
- fscache_stat(&fscache_n_store_ops);
- fscache_stat(&fscache_n_stores_ok);
-
- /* the work queue now carries its own ref on the object */
- fscache_put_operation(&op->op);
- _leave(" = 0");
- return 0;
-
-already_queued:
- fscache_stat(&fscache_n_stores_again);
-already_pending:
- spin_unlock(&cookie->stores_lock);
- spin_unlock(&object->lock);
- spin_unlock(&cookie->lock);
- radix_tree_preload_end();
- fscache_put_operation(&op->op);
- fscache_stat(&fscache_n_stores_ok);
- _leave(" = 0");
- return 0;
-
-submit_failed:
- spin_lock(&cookie->stores_lock);
- radix_tree_delete(&cookie->stores, page->index);
- trace_fscache_page(cookie, page, fscache_page_radix_delete);
- spin_unlock(&cookie->stores_lock);
- wake_cookie = __fscache_unuse_cookie(cookie);
- put_page(page);
- ret = -ENOBUFS;
- goto nobufs;
-
-nobufs_unlock_obj:
- spin_unlock(&cookie->stores_lock);
- spin_unlock(&object->lock);
-nobufs:
- spin_unlock(&cookie->lock);
- radix_tree_preload_end();
- fscache_put_operation(&op->op);
- if (wake_cookie)
- __fscache_wake_unused_cookie(cookie);
- fscache_stat(&fscache_n_stores_nobufs);
- _leave(" = -ENOBUFS");
- return -ENOBUFS;
-
-nomem_free:
- fscache_put_operation(&op->op);
-nomem:
- fscache_stat(&fscache_n_stores_oom);
- _leave(" = -ENOMEM");
- return -ENOMEM;
-}
-EXPORT_SYMBOL(__fscache_write_page);
-
-/*
- * remove a page from the cache
- */
-void __fscache_uncache_page(struct fscache_cookie *cookie, struct page *page)
-{
- struct fscache_object *object;
-
- _enter(",%p", page);
-
- ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX);
- ASSERTCMP(page, !=, NULL);
-
- fscache_stat(&fscache_n_uncaches);
-
- /* cache withdrawal may beat us to it */
- if (!PageFsCache(page))
- goto done;
-
- trace_fscache_page(cookie, page, fscache_page_uncache);
-
- /* get the object */
- spin_lock(&cookie->lock);
-
- if (hlist_empty(&cookie->backing_objects)) {
- ClearPageFsCache(page);
- goto done_unlock;
- }
-
- object = hlist_entry(cookie->backing_objects.first,
- struct fscache_object, cookie_link);
-
- /* there might now be stuff on disk we could read */
- clear_bit(FSCACHE_COOKIE_NO_DATA_YET, &cookie->flags);
-
- /* only invoke the cache backend if we managed to mark the page
- * uncached here; this deals with synchronisation vs withdrawal */
- if (TestClearPageFsCache(page) &&
- object->cache->ops->uncache_page) {
- /* the cache backend releases the cookie lock */
- fscache_stat(&fscache_n_cop_uncache_page);
- object->cache->ops->uncache_page(object, page);
- fscache_stat_d(&fscache_n_cop_uncache_page);
- goto done;
- }
-
-done_unlock:
- spin_unlock(&cookie->lock);
-done:
- _leave("");
-}
-EXPORT_SYMBOL(__fscache_uncache_page);
-
-/**
- * fscache_mark_page_cached - Mark a page as being cached
- * @op: The retrieval op pages are being marked for
- * @page: The page to be marked
- *
- * Mark a netfs page as being cached. After this is called, the netfs
- * must call fscache_uncache_page() to remove the mark.
- */
-void fscache_mark_page_cached(struct fscache_retrieval *op, struct page *page)
-{
- struct fscache_cookie *cookie = op->op.object->cookie;
-
-#ifdef CONFIG_FSCACHE_STATS
- atomic_inc(&fscache_n_marks);
-#endif
-
- trace_fscache_page(cookie, page, fscache_page_cached);
-
- _debug("- mark %p{%lx}", page, page->index);
- if (TestSetPageFsCache(page)) {
- static bool once_only;
- if (!once_only) {
- once_only = true;
- pr_warn("Cookie type %s marked page %lx multiple times\n",
- cookie->def->name, page->index);
- }
- }
-
- if (cookie->def->mark_page_cached)
- cookie->def->mark_page_cached(cookie->netfs_data,
- op->mapping, page);
-}
-EXPORT_SYMBOL(fscache_mark_page_cached);
-
-/**
- * fscache_mark_pages_cached - Mark pages as being cached
- * @op: The retrieval op pages are being marked for
- * @pagevec: The pages to be marked
- *
- * Mark a bunch of netfs pages as being cached. After this is called,
- * the netfs must call fscache_uncache_page() to remove the mark.
- */
-void fscache_mark_pages_cached(struct fscache_retrieval *op,
- struct pagevec *pagevec)
-{
- unsigned long loop;
-
- for (loop = 0; loop < pagevec->nr; loop++)
- fscache_mark_page_cached(op, pagevec->pages[loop]);
-
- pagevec_reinit(pagevec);
-}
-EXPORT_SYMBOL(fscache_mark_pages_cached);
-
-/*
- * Uncache all the pages in an inode that are marked PG_fscache, assuming them
- * to be associated with the given cookie.
- */
-void __fscache_uncache_all_inode_pages(struct fscache_cookie *cookie,
- struct inode *inode)
-{
- struct address_space *mapping = inode->i_mapping;
- struct pagevec pvec;
- pgoff_t next;
- int i;
-
- _enter("%p,%p", cookie, inode);
-
- if (!mapping || mapping->nrpages == 0) {
- _leave(" [no pages]");
- return;
- }
-
- pagevec_init(&pvec);
- next = 0;
- do {
- if (!pagevec_lookup(&pvec, mapping, &next))
- break;
- for (i = 0; i < pagevec_count(&pvec); i++) {
- struct page *page = pvec.pages[i];
- if (PageFsCache(page)) {
- __fscache_wait_on_page_write(cookie, page);
- __fscache_uncache_page(cookie, page);
- }
- }
- pagevec_release(&pvec);
- cond_resched();
- } while (next);
-
- _leave("");
-}
-EXPORT_SYMBOL(__fscache_uncache_all_inode_pages);
+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* FS-Cache statistics viewing interface
- *
- * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- */
-
-#define FSCACHE_DEBUG_LEVEL OPERATION
-#include <linux/module.h>
-#include <linux/proc_fs.h>
-#include <linux/seq_file.h>
-#include "internal.h"
-
-/*
- * initialise the /proc/fs/fscache/ directory
- */
-int __init fscache_proc_init(void)
-{
- _enter("");
-
- if (!proc_mkdir("fs/fscache", NULL))
- goto error_dir;
-
- if (!proc_create_seq("fs/fscache/cookies", S_IFREG | 0444, NULL,
- &fscache_cookies_seq_ops))
- goto error_cookies;
-
-#ifdef CONFIG_FSCACHE_STATS
- if (!proc_create_single("fs/fscache/stats", S_IFREG | 0444, NULL,
- fscache_stats_show))
- goto error_stats;
-#endif
-
-#ifdef CONFIG_FSCACHE_OBJECT_LIST
- if (!proc_create("fs/fscache/objects", S_IFREG | 0444, NULL,
- &fscache_objlist_proc_ops))
- goto error_objects;
-#endif
-
- _leave(" = 0");
- return 0;
-
-#ifdef CONFIG_FSCACHE_OBJECT_LIST
-error_objects:
-#endif
-#ifdef CONFIG_FSCACHE_STATS
- remove_proc_entry("fs/fscache/stats", NULL);
-error_stats:
-#endif
- remove_proc_entry("fs/fscache/cookies", NULL);
-error_cookies:
- remove_proc_entry("fs/fscache", NULL);
-error_dir:
- _leave(" = -ENOMEM");
- return -ENOMEM;
-}
-
-/*
- * clean up the /proc/fs/fscache/ directory
- */
-void fscache_proc_cleanup(void)
-{
-#ifdef CONFIG_FSCACHE_OBJECT_LIST
- remove_proc_entry("fs/fscache/objects", NULL);
-#endif
-#ifdef CONFIG_FSCACHE_STATS
- remove_proc_entry("fs/fscache/stats", NULL);
-#endif
- remove_proc_entry("fs/fscache/cookies", NULL);
- remove_proc_entry("fs/fscache", NULL);
-}
+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* FS-Cache statistics
- *
- * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- */
-
-#define FSCACHE_DEBUG_LEVEL THREAD
-#include <linux/module.h>
-#include <linux/proc_fs.h>
-#include <linux/seq_file.h>
-#include "internal.h"
-
-/*
- * operation counters
- */
-atomic_t fscache_n_op_pend;
-atomic_t fscache_n_op_run;
-atomic_t fscache_n_op_enqueue;
-atomic_t fscache_n_op_deferred_release;
-atomic_t fscache_n_op_initialised;
-atomic_t fscache_n_op_release;
-atomic_t fscache_n_op_gc;
-atomic_t fscache_n_op_cancelled;
-atomic_t fscache_n_op_rejected;
-
-atomic_t fscache_n_attr_changed;
-atomic_t fscache_n_attr_changed_ok;
-atomic_t fscache_n_attr_changed_nobufs;
-atomic_t fscache_n_attr_changed_nomem;
-atomic_t fscache_n_attr_changed_calls;
-
-atomic_t fscache_n_allocs;
-atomic_t fscache_n_allocs_ok;
-atomic_t fscache_n_allocs_wait;
-atomic_t fscache_n_allocs_nobufs;
-atomic_t fscache_n_allocs_intr;
-atomic_t fscache_n_allocs_object_dead;
-atomic_t fscache_n_alloc_ops;
-atomic_t fscache_n_alloc_op_waits;
-
-atomic_t fscache_n_retrievals;
-atomic_t fscache_n_retrievals_ok;
-atomic_t fscache_n_retrievals_wait;
-atomic_t fscache_n_retrievals_nodata;
-atomic_t fscache_n_retrievals_nobufs;
-atomic_t fscache_n_retrievals_intr;
-atomic_t fscache_n_retrievals_nomem;
-atomic_t fscache_n_retrievals_object_dead;
-atomic_t fscache_n_retrieval_ops;
-atomic_t fscache_n_retrieval_op_waits;
-
-atomic_t fscache_n_stores;
-atomic_t fscache_n_stores_ok;
-atomic_t fscache_n_stores_again;
-atomic_t fscache_n_stores_nobufs;
-atomic_t fscache_n_stores_oom;
-atomic_t fscache_n_store_ops;
-atomic_t fscache_n_store_calls;
-atomic_t fscache_n_store_pages;
-atomic_t fscache_n_store_radix_deletes;
-atomic_t fscache_n_store_pages_over_limit;
-
-atomic_t fscache_n_store_vmscan_not_storing;
-atomic_t fscache_n_store_vmscan_gone;
-atomic_t fscache_n_store_vmscan_busy;
-atomic_t fscache_n_store_vmscan_cancelled;
-atomic_t fscache_n_store_vmscan_wait;
-
-atomic_t fscache_n_marks;
-atomic_t fscache_n_uncaches;
-
-atomic_t fscache_n_acquires;
-atomic_t fscache_n_acquires_null;
-atomic_t fscache_n_acquires_no_cache;
-atomic_t fscache_n_acquires_ok;
-atomic_t fscache_n_acquires_nobufs;
-atomic_t fscache_n_acquires_oom;
-
-atomic_t fscache_n_invalidates;
-atomic_t fscache_n_invalidates_run;
-
-atomic_t fscache_n_updates;
-atomic_t fscache_n_updates_null;
-atomic_t fscache_n_updates_run;
-
-atomic_t fscache_n_relinquishes;
-atomic_t fscache_n_relinquishes_null;
-atomic_t fscache_n_relinquishes_waitcrt;
-atomic_t fscache_n_relinquishes_retire;
-
-atomic_t fscache_n_cookie_index;
-atomic_t fscache_n_cookie_data;
-atomic_t fscache_n_cookie_special;
-
-atomic_t fscache_n_object_alloc;
-atomic_t fscache_n_object_no_alloc;
-atomic_t fscache_n_object_lookups;
-atomic_t fscache_n_object_lookups_negative;
-atomic_t fscache_n_object_lookups_positive;
-atomic_t fscache_n_object_lookups_timed_out;
-atomic_t fscache_n_object_created;
-atomic_t fscache_n_object_avail;
-atomic_t fscache_n_object_dead;
-
-atomic_t fscache_n_checkaux_none;
-atomic_t fscache_n_checkaux_okay;
-atomic_t fscache_n_checkaux_update;
-atomic_t fscache_n_checkaux_obsolete;
-
-atomic_t fscache_n_cop_alloc_object;
-atomic_t fscache_n_cop_lookup_object;
-atomic_t fscache_n_cop_lookup_complete;
-atomic_t fscache_n_cop_grab_object;
-atomic_t fscache_n_cop_invalidate_object;
-atomic_t fscache_n_cop_update_object;
-atomic_t fscache_n_cop_drop_object;
-atomic_t fscache_n_cop_put_object;
-atomic_t fscache_n_cop_sync_cache;
-atomic_t fscache_n_cop_attr_changed;
-atomic_t fscache_n_cop_read_or_alloc_page;
-atomic_t fscache_n_cop_read_or_alloc_pages;
-atomic_t fscache_n_cop_allocate_page;
-atomic_t fscache_n_cop_allocate_pages;
-atomic_t fscache_n_cop_write_page;
-atomic_t fscache_n_cop_uncache_page;
-atomic_t fscache_n_cop_dissociate_pages;
-
-atomic_t fscache_n_cache_no_space_reject;
-atomic_t fscache_n_cache_stale_objects;
-atomic_t fscache_n_cache_retired_objects;
-atomic_t fscache_n_cache_culled_objects;
-
-/*
- * display the general statistics
- */
-int fscache_stats_show(struct seq_file *m, void *v)
-{
- seq_puts(m, "FS-Cache statistics\n");
-
- seq_printf(m, "Cookies: idx=%u dat=%u spc=%u\n",
- atomic_read(&fscache_n_cookie_index),
- atomic_read(&fscache_n_cookie_data),
- atomic_read(&fscache_n_cookie_special));
-
- seq_printf(m, "Objects: alc=%u nal=%u avl=%u ded=%u\n",
- atomic_read(&fscache_n_object_alloc),
- atomic_read(&fscache_n_object_no_alloc),
- atomic_read(&fscache_n_object_avail),
- atomic_read(&fscache_n_object_dead));
- seq_printf(m, "ChkAux : non=%u ok=%u upd=%u obs=%u\n",
- atomic_read(&fscache_n_checkaux_none),
- atomic_read(&fscache_n_checkaux_okay),
- atomic_read(&fscache_n_checkaux_update),
- atomic_read(&fscache_n_checkaux_obsolete));
-
- seq_printf(m, "Pages : mrk=%u unc=%u\n",
- atomic_read(&fscache_n_marks),
- atomic_read(&fscache_n_uncaches));
-
- seq_printf(m, "Acquire: n=%u nul=%u noc=%u ok=%u nbf=%u"
- " oom=%u\n",
- atomic_read(&fscache_n_acquires),
- atomic_read(&fscache_n_acquires_null),
- atomic_read(&fscache_n_acquires_no_cache),
- atomic_read(&fscache_n_acquires_ok),
- atomic_read(&fscache_n_acquires_nobufs),
- atomic_read(&fscache_n_acquires_oom));
-
- seq_printf(m, "Lookups: n=%u neg=%u pos=%u crt=%u tmo=%u\n",
- atomic_read(&fscache_n_object_lookups),
- atomic_read(&fscache_n_object_lookups_negative),
- atomic_read(&fscache_n_object_lookups_positive),
- atomic_read(&fscache_n_object_created),
- atomic_read(&fscache_n_object_lookups_timed_out));
-
- seq_printf(m, "Invals : n=%u run=%u\n",
- atomic_read(&fscache_n_invalidates),
- atomic_read(&fscache_n_invalidates_run));
-
- seq_printf(m, "Updates: n=%u nul=%u run=%u\n",
- atomic_read(&fscache_n_updates),
- atomic_read(&fscache_n_updates_null),
- atomic_read(&fscache_n_updates_run));
-
- seq_printf(m, "Relinqs: n=%u nul=%u wcr=%u rtr=%u\n",
- atomic_read(&fscache_n_relinquishes),
- atomic_read(&fscache_n_relinquishes_null),
- atomic_read(&fscache_n_relinquishes_waitcrt),
- atomic_read(&fscache_n_relinquishes_retire));
-
- seq_printf(m, "AttrChg: n=%u ok=%u nbf=%u oom=%u run=%u\n",
- atomic_read(&fscache_n_attr_changed),
- atomic_read(&fscache_n_attr_changed_ok),
- atomic_read(&fscache_n_attr_changed_nobufs),
- atomic_read(&fscache_n_attr_changed_nomem),
- atomic_read(&fscache_n_attr_changed_calls));
-
- seq_printf(m, "Allocs : n=%u ok=%u wt=%u nbf=%u int=%u\n",
- atomic_read(&fscache_n_allocs),
- atomic_read(&fscache_n_allocs_ok),
- atomic_read(&fscache_n_allocs_wait),
- atomic_read(&fscache_n_allocs_nobufs),
- atomic_read(&fscache_n_allocs_intr));
- seq_printf(m, "Allocs : ops=%u owt=%u abt=%u\n",
- atomic_read(&fscache_n_alloc_ops),
- atomic_read(&fscache_n_alloc_op_waits),
- atomic_read(&fscache_n_allocs_object_dead));
-
- seq_printf(m, "Retrvls: n=%u ok=%u wt=%u nod=%u nbf=%u"
- " int=%u oom=%u\n",
- atomic_read(&fscache_n_retrievals),
- atomic_read(&fscache_n_retrievals_ok),
- atomic_read(&fscache_n_retrievals_wait),
- atomic_read(&fscache_n_retrievals_nodata),
- atomic_read(&fscache_n_retrievals_nobufs),
- atomic_read(&fscache_n_retrievals_intr),
- atomic_read(&fscache_n_retrievals_nomem));
- seq_printf(m, "Retrvls: ops=%u owt=%u abt=%u\n",
- atomic_read(&fscache_n_retrieval_ops),
- atomic_read(&fscache_n_retrieval_op_waits),
- atomic_read(&fscache_n_retrievals_object_dead));
-
- seq_printf(m, "Stores : n=%u ok=%u agn=%u nbf=%u oom=%u\n",
- atomic_read(&fscache_n_stores),
- atomic_read(&fscache_n_stores_ok),
- atomic_read(&fscache_n_stores_again),
- atomic_read(&fscache_n_stores_nobufs),
- atomic_read(&fscache_n_stores_oom));
- seq_printf(m, "Stores : ops=%u run=%u pgs=%u rxd=%u olm=%u\n",
- atomic_read(&fscache_n_store_ops),
- atomic_read(&fscache_n_store_calls),
- atomic_read(&fscache_n_store_pages),
- atomic_read(&fscache_n_store_radix_deletes),
- atomic_read(&fscache_n_store_pages_over_limit));
-
- seq_printf(m, "VmScan : nos=%u gon=%u bsy=%u can=%u wt=%u\n",
- atomic_read(&fscache_n_store_vmscan_not_storing),
- atomic_read(&fscache_n_store_vmscan_gone),
- atomic_read(&fscache_n_store_vmscan_busy),
- atomic_read(&fscache_n_store_vmscan_cancelled),
- atomic_read(&fscache_n_store_vmscan_wait));
-
- seq_printf(m, "Ops : pend=%u run=%u enq=%u can=%u rej=%u\n",
- atomic_read(&fscache_n_op_pend),
- atomic_read(&fscache_n_op_run),
- atomic_read(&fscache_n_op_enqueue),
- atomic_read(&fscache_n_op_cancelled),
- atomic_read(&fscache_n_op_rejected));
- seq_printf(m, "Ops : ini=%u dfr=%u rel=%u gc=%u\n",
- atomic_read(&fscache_n_op_initialised),
- atomic_read(&fscache_n_op_deferred_release),
- atomic_read(&fscache_n_op_release),
- atomic_read(&fscache_n_op_gc));
-
- seq_printf(m, "CacheOp: alo=%d luo=%d luc=%d gro=%d\n",
- atomic_read(&fscache_n_cop_alloc_object),
- atomic_read(&fscache_n_cop_lookup_object),
- atomic_read(&fscache_n_cop_lookup_complete),
- atomic_read(&fscache_n_cop_grab_object));
- seq_printf(m, "CacheOp: inv=%d upo=%d dro=%d pto=%d atc=%d syn=%d\n",
- atomic_read(&fscache_n_cop_invalidate_object),
- atomic_read(&fscache_n_cop_update_object),
- atomic_read(&fscache_n_cop_drop_object),
- atomic_read(&fscache_n_cop_put_object),
- atomic_read(&fscache_n_cop_attr_changed),
- atomic_read(&fscache_n_cop_sync_cache));
- seq_printf(m, "CacheOp: rap=%d ras=%d alp=%d als=%d wrp=%d ucp=%d dsp=%d\n",
- atomic_read(&fscache_n_cop_read_or_alloc_page),
- atomic_read(&fscache_n_cop_read_or_alloc_pages),
- atomic_read(&fscache_n_cop_allocate_page),
- atomic_read(&fscache_n_cop_allocate_pages),
- atomic_read(&fscache_n_cop_write_page),
- atomic_read(&fscache_n_cop_uncache_page),
- atomic_read(&fscache_n_cop_dissociate_pages));
- seq_printf(m, "CacheEv: nsp=%d stl=%d rtr=%d cul=%d\n",
- atomic_read(&fscache_n_cache_no_space_reject),
- atomic_read(&fscache_n_cache_stale_objects),
- atomic_read(&fscache_n_cache_retired_objects),
- atomic_read(&fscache_n_cache_culled_objects));
- netfs_stats_show(m);
- return 0;
-}
/* SPDX-License-Identifier: GPL-2.0-or-later */
/* General filesystem caching backing cache interface
*
- * Copyright (C) 2004-2007 Red Hat, Inc. All Rights Reserved.
+ * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* NOTE!!! See:
#define _LINUX_FSCACHE_CACHE_H
#include <linux/fscache.h>
-#include <linux/sched.h>
-#include <linux/workqueue.h>
-
-#define NR_MAXCACHES BITS_PER_LONG
-
-struct fscache_cache;
-struct fscache_cache_ops;
-struct fscache_object;
-struct fscache_operation;
-
-enum fscache_obj_ref_trace {
- fscache_obj_get_add_to_deps,
- fscache_obj_get_queue,
- fscache_obj_put_alloc_fail,
- fscache_obj_put_attach_fail,
- fscache_obj_put_drop_obj,
- fscache_obj_put_enq_dep,
- fscache_obj_put_queue,
- fscache_obj_put_work,
- fscache_obj_ref__nr_traces
-};
-
-/*
- * cache tag definition
- */
-struct fscache_cache_tag {
- struct list_head link;
- struct fscache_cache *cache; /* cache referred to by this tag */
- unsigned long flags;
-#define FSCACHE_TAG_RESERVED 0 /* T if tag is reserved for a cache */
- atomic_t usage;
- char name[]; /* tag name */
-};
-
-/*
- * cache definition
- */
-struct fscache_cache {
- const struct fscache_cache_ops *ops;
- struct fscache_cache_tag *tag; /* tag representing this cache */
- struct kobject *kobj; /* system representation of this cache */
- struct list_head link; /* link in list of caches */
- size_t max_index_size; /* maximum size of index data */
- char identifier[36]; /* cache label */
-
- /* node management */
- struct work_struct op_gc; /* operation garbage collector */
- struct list_head object_list; /* list of data/index objects */
- struct list_head op_gc_list; /* list of ops to be deleted */
- spinlock_t object_list_lock;
- spinlock_t op_gc_list_lock;
- atomic_t object_count; /* no. of live objects in this cache */
- struct fscache_object *fsdef; /* object for the fsdef index */
- unsigned long flags;
-#define FSCACHE_IOERROR 0 /* cache stopped on I/O error */
-#define FSCACHE_CACHE_WITHDRAWN 1 /* cache has been withdrawn */
-};
-
-extern wait_queue_head_t fscache_cache_cleared_wq;
-
-/*
- * operation to be applied to a cache object
- * - retrieval initiation operations are done in the context of the process
- * that issued them, and not in an async thread pool
- */
-typedef void (*fscache_operation_release_t)(struct fscache_operation *op);
-typedef void (*fscache_operation_processor_t)(struct fscache_operation *op);
-typedef void (*fscache_operation_cancel_t)(struct fscache_operation *op);
-
-enum fscache_operation_state {
- FSCACHE_OP_ST_BLANK, /* Op is not yet submitted */
- FSCACHE_OP_ST_INITIALISED, /* Op is initialised */
- FSCACHE_OP_ST_PENDING, /* Op is blocked from running */
- FSCACHE_OP_ST_IN_PROGRESS, /* Op is in progress */
- FSCACHE_OP_ST_COMPLETE, /* Op is complete */
- FSCACHE_OP_ST_CANCELLED, /* Op has been cancelled */
- FSCACHE_OP_ST_DEAD /* Op is now dead */
-};
-
-struct fscache_operation {
- struct work_struct work; /* record for async ops */
- struct list_head pend_link; /* link in object->pending_ops */
- struct fscache_object *object; /* object to be operated upon */
-
- unsigned long flags;
-#define FSCACHE_OP_TYPE 0x000f /* operation type */
-#define FSCACHE_OP_ASYNC 0x0001 /* - async op, processor may sleep for disk */
-#define FSCACHE_OP_MYTHREAD 0x0002 /* - processing is done be issuing thread, not pool */
-#define FSCACHE_OP_WAITING 4 /* cleared when op is woken */
-#define FSCACHE_OP_EXCLUSIVE 5 /* exclusive op, other ops must wait */
-#define FSCACHE_OP_DEC_READ_CNT 6 /* decrement object->n_reads on destruction */
-#define FSCACHE_OP_UNUSE_COOKIE 7 /* call fscache_unuse_cookie() on completion */
-#define FSCACHE_OP_KEEP_FLAGS 0x00f0 /* flags to keep when repurposing an op */
-
- enum fscache_operation_state state;
- atomic_t usage;
- unsigned debug_id; /* debugging ID */
-
- /* operation processor callback
- * - can be NULL if FSCACHE_OP_WAITING is going to be used to perform
- * the op in a non-pool thread */
- fscache_operation_processor_t processor;
-
- /* Operation cancellation cleanup (optional) */
- fscache_operation_cancel_t cancel;
-
- /* operation releaser */
- fscache_operation_release_t release;
-};
-
-extern atomic_t fscache_op_debug_id;
-extern void fscache_op_work_func(struct work_struct *work);
-
-extern void fscache_enqueue_operation(struct fscache_operation *);
-extern void fscache_op_complete(struct fscache_operation *, bool);
-extern void fscache_put_operation(struct fscache_operation *);
-extern void fscache_operation_init(struct fscache_cookie *,
- struct fscache_operation *,
- fscache_operation_processor_t,
- fscache_operation_cancel_t,
- fscache_operation_release_t);
-
-/*
- * data read operation
- */
-struct fscache_retrieval {
- struct fscache_operation op;
- struct fscache_cookie *cookie; /* The netfs cookie */
- struct address_space *mapping; /* netfs pages */
- fscache_rw_complete_t end_io_func; /* function to call on I/O completion */
- void *context; /* netfs read context (pinned) */
- struct list_head to_do; /* list of things to be done by the backend */
- atomic_t n_pages; /* number of pages to be retrieved */
-};
-
-typedef int (*fscache_page_retrieval_func_t)(struct fscache_retrieval *op,
- struct page *page,
- gfp_t gfp);
-
-typedef int (*fscache_pages_retrieval_func_t)(struct fscache_retrieval *op,
- struct list_head *pages,
- unsigned *nr_pages,
- gfp_t gfp);
-
-/**
- * fscache_get_retrieval - Get an extra reference on a retrieval operation
- * @op: The retrieval operation to get a reference on
- *
- * Get an extra reference on a retrieval operation.
- */
-static inline
-struct fscache_retrieval *fscache_get_retrieval(struct fscache_retrieval *op)
-{
- atomic_inc(&op->op.usage);
- return op;
-}
-
-/**
- * fscache_enqueue_retrieval - Enqueue a retrieval operation for processing
- * @op: The retrieval operation affected
- *
- * Enqueue a retrieval operation for processing by the FS-Cache thread pool.
- */
-static inline void fscache_enqueue_retrieval(struct fscache_retrieval *op)
-{
- fscache_enqueue_operation(&op->op);
-}
-
-/**
- * fscache_retrieval_complete - Record (partial) completion of a retrieval
- * @op: The retrieval operation affected
- * @n_pages: The number of pages to account for
- */
-static inline void fscache_retrieval_complete(struct fscache_retrieval *op,
- int n_pages)
-{
- if (atomic_sub_return_relaxed(n_pages, &op->n_pages) <= 0)
- fscache_op_complete(&op->op, false);
-}
-
-/**
- * fscache_put_retrieval - Drop a reference to a retrieval operation
- * @op: The retrieval operation affected
- *
- * Drop a reference to a retrieval operation.
- */
-static inline void fscache_put_retrieval(struct fscache_retrieval *op)
-{
- fscache_put_operation(&op->op);
-}
-
-/*
- * cached page storage work item
- * - used to do three things:
- * - batch writes to the cache
- * - do cache writes asynchronously
- * - defer writes until cache object lookup completion
- */
-struct fscache_storage {
- struct fscache_operation op;
- pgoff_t store_limit; /* don't write more than this */
-};
-
-/*
- * cache operations
- */
-struct fscache_cache_ops {
- /* name of cache provider */
- const char *name;
-
- /* allocate an object record for a cookie */
- struct fscache_object *(*alloc_object)(struct fscache_cache *cache,
- struct fscache_cookie *cookie);
-
- /* look up the object for a cookie
- * - return -ETIMEDOUT to be requeued
- */
- int (*lookup_object)(struct fscache_object *object);
-
- /* finished looking up */
- void (*lookup_complete)(struct fscache_object *object);
-
- /* increment the usage count on this object (may fail if unmounting) */
- struct fscache_object *(*grab_object)(struct fscache_object *object,
- enum fscache_obj_ref_trace why);
-
- /* pin an object in the cache */
- int (*pin_object)(struct fscache_object *object);
-
- /* unpin an object in the cache */
- void (*unpin_object)(struct fscache_object *object);
-
- /* check the consistency between the backing cache and the FS-Cache
- * cookie */
- int (*check_consistency)(struct fscache_operation *op);
-
- /* store the updated auxiliary data on an object */
- void (*update_object)(struct fscache_object *object);
-
- /* Invalidate an object */
- void (*invalidate_object)(struct fscache_operation *op);
-
- /* discard the resources pinned by an object and effect retirement if
- * necessary */
- void (*drop_object)(struct fscache_object *object);
-
- /* dispose of a reference to an object */
- void (*put_object)(struct fscache_object *object,
- enum fscache_obj_ref_trace why);
-
- /* sync a cache */
- void (*sync_cache)(struct fscache_cache *cache);
-
- /* notification that the attributes of a non-index object (such as
- * i_size) have changed */
- int (*attr_changed)(struct fscache_object *object);
-
- /* reserve space for an object's data and associated metadata */
- int (*reserve_space)(struct fscache_object *object, loff_t i_size);
-
- /* request a backing block for a page be read or allocated in the
- * cache */
- fscache_page_retrieval_func_t read_or_alloc_page;
-
- /* request backing blocks for a list of pages be read or allocated in
- * the cache */
- fscache_pages_retrieval_func_t read_or_alloc_pages;
-
- /* request a backing block for a page be allocated in the cache so that
- * it can be written directly */
- fscache_page_retrieval_func_t allocate_page;
-
- /* request backing blocks for pages be allocated in the cache so that
- * they can be written directly */
- fscache_pages_retrieval_func_t allocate_pages;
-
- /* write a page to its backing block in the cache */
- int (*write_page)(struct fscache_storage *op, struct page *page);
-
- /* detach backing block from a page (optional)
- * - must release the cookie lock before returning
- * - may sleep
- */
- void (*uncache_page)(struct fscache_object *object,
- struct page *page);
-
- /* dissociate a cache from all the pages it was backing */
- void (*dissociate_pages)(struct fscache_cache *cache);
-
- /* Begin a read operation for the netfs lib */
- int (*begin_read_operation)(struct netfs_read_request *rreq,
- struct fscache_retrieval *op);
-};
-
-extern struct fscache_cookie fscache_fsdef_index;
-
-/*
- * Event list for fscache_object::{event_mask,events}
- */
-enum {
- FSCACHE_OBJECT_EV_NEW_CHILD, /* T if object has a new child */
- FSCACHE_OBJECT_EV_PARENT_READY, /* T if object's parent is ready */
- FSCACHE_OBJECT_EV_UPDATE, /* T if object should be updated */
- FSCACHE_OBJECT_EV_INVALIDATE, /* T if cache requested object invalidation */
- FSCACHE_OBJECT_EV_CLEARED, /* T if accessors all gone */
- FSCACHE_OBJECT_EV_ERROR, /* T if fatal error occurred during processing */
- FSCACHE_OBJECT_EV_KILL, /* T if netfs relinquished or cache withdrew object */
- NR_FSCACHE_OBJECT_EVENTS
-};
-
-#define FSCACHE_OBJECT_EVENTS_MASK ((1UL << NR_FSCACHE_OBJECT_EVENTS) - 1)
-
-/*
- * States for object state machine.
- */
-struct fscache_transition {
- unsigned long events;
- const struct fscache_state *transit_to;
-};
-
-struct fscache_state {
- char name[24];
- char short_name[8];
- const struct fscache_state *(*work)(struct fscache_object *object,
- int event);
- const struct fscache_transition transitions[];
-};
-
-/*
- * on-disk cache file or index handle
- */
-struct fscache_object {
- const struct fscache_state *state; /* Object state machine state */
- const struct fscache_transition *oob_table; /* OOB state transition table */
- int debug_id; /* debugging ID */
- int n_children; /* number of child objects */
- int n_ops; /* number of extant ops on object */
- int n_obj_ops; /* number of object ops outstanding on object */
- int n_in_progress; /* number of ops in progress */
- int n_exclusive; /* number of exclusive ops queued or in progress */
- atomic_t n_reads; /* number of read ops in progress */
- spinlock_t lock; /* state and operations lock */
-
- unsigned long lookup_jif; /* time at which lookup started */
- unsigned long oob_event_mask; /* OOB events this object is interested in */
- unsigned long event_mask; /* events this object is interested in */
- unsigned long events; /* events to be processed by this object
- * (order is important - using fls) */
-
- unsigned long flags;
-#define FSCACHE_OBJECT_LOCK 0 /* T if object is busy being processed */
-#define FSCACHE_OBJECT_PENDING_WRITE 1 /* T if object has pending write */
-#define FSCACHE_OBJECT_WAITING 2 /* T if object is waiting on its parent */
-#define FSCACHE_OBJECT_IS_LIVE 3 /* T if object is not withdrawn or relinquished */
-#define FSCACHE_OBJECT_IS_LOOKED_UP 4 /* T if object has been looked up */
-#define FSCACHE_OBJECT_IS_AVAILABLE 5 /* T if object has become active */
-#define FSCACHE_OBJECT_RETIRED 6 /* T if object was retired on relinquishment */
-#define FSCACHE_OBJECT_KILLED_BY_CACHE 7 /* T if object was killed by the cache */
-#define FSCACHE_OBJECT_RUN_AFTER_DEAD 8 /* T if object has been dispatched after death */
-
- struct list_head cache_link; /* link in cache->object_list */
- struct hlist_node cookie_link; /* link in cookie->backing_objects */
- struct fscache_cache *cache; /* cache that supplied this object */
- struct fscache_cookie *cookie; /* netfs's file/index object */
- struct fscache_object *parent; /* parent object */
- struct work_struct work; /* attention scheduling record */
- struct list_head dependents; /* FIFO of dependent objects */
- struct list_head dep_link; /* link in parent's dependents list */
- struct list_head pending_ops; /* unstarted operations on this object */
- pgoff_t store_limit; /* current storage limit */
- loff_t store_limit_l; /* current storage limit */
-};
-
-extern void fscache_object_init(struct fscache_object *, struct fscache_cookie *,
- struct fscache_cache *);
-extern void fscache_object_destroy(struct fscache_object *);
-
-extern void fscache_object_lookup_negative(struct fscache_object *object);
-extern void fscache_obtained_object(struct fscache_object *object);
-
-static inline bool fscache_object_is_live(struct fscache_object *object)
-{
- return test_bit(FSCACHE_OBJECT_IS_LIVE, &object->flags);
-}
-
-static inline bool fscache_object_is_dying(struct fscache_object *object)
-{
- return !fscache_object_is_live(object);
-}
-
-static inline bool fscache_object_is_available(struct fscache_object *object)
-{
- return test_bit(FSCACHE_OBJECT_IS_AVAILABLE, &object->flags);
-}
-
-static inline bool fscache_cache_is_broken(struct fscache_object *object)
-{
- return test_bit(FSCACHE_IOERROR, &object->cache->flags);
-}
-
-static inline bool fscache_object_is_active(struct fscache_object *object)
-{
- return fscache_object_is_available(object) &&
- fscache_object_is_live(object) &&
- !fscache_cache_is_broken(object);
-}
-
-/**
- * fscache_object_destroyed - Note destruction of an object in a cache
- * @cache: The cache from which the object came
- *
- * Note the destruction and deallocation of an object record in a cache.
- */
-static inline void fscache_object_destroyed(struct fscache_cache *cache)
-{
- if (atomic_dec_and_test(&cache->object_count))
- wake_up_all(&fscache_cache_cleared_wq);
-}
-
-/**
- * fscache_object_lookup_error - Note an object encountered an error
- * @object: The object on which the error was encountered
- *
- * Note that an object encountered a fatal error (usually an I/O error) and
- * that it should be withdrawn as soon as possible.
- */
-static inline void fscache_object_lookup_error(struct fscache_object *object)
-{
- set_bit(FSCACHE_OBJECT_EV_ERROR, &object->events);
-}
-
-/**
- * fscache_set_store_limit - Set the maximum size to be stored in an object
- * @object: The object to set the maximum on
- * @i_size: The limit to set in bytes
- *
- * Set the maximum size an object is permitted to reach, implying the highest
- * byte that may be written. Intended to be called by the attr_changed() op.
- *
- * See Documentation/filesystems/caching/backend-api.rst for a complete
- * description.
- */
-static inline
-void fscache_set_store_limit(struct fscache_object *object, loff_t i_size)
-{
- object->store_limit_l = i_size;
- object->store_limit = i_size >> PAGE_SHIFT;
- if (i_size & ~PAGE_MASK)
- object->store_limit++;
-}
-
-/**
- * fscache_end_io - End a retrieval operation on a page
- * @op: The FS-Cache operation covering the retrieval
- * @page: The page that was to be fetched
- * @error: The error code (0 if successful)
- *
- * Note the end of an operation to retrieve a page, as covered by a particular
- * operation record.
- */
-static inline void fscache_end_io(struct fscache_retrieval *op,
- struct page *page, int error)
-{
- op->end_io_func(page, op->context, error);
-}
-
-static inline void __fscache_use_cookie(struct fscache_cookie *cookie)
-{
- atomic_inc(&cookie->n_active);
-}
-
-/**
- * fscache_use_cookie - Request usage of cookie attached to an object
- * @object: Object description
- *
- * Request usage of the cookie attached to an object. NULL is returned if the
- * relinquishment had reduced the cookie usage count to 0.
- */
-static inline bool fscache_use_cookie(struct fscache_object *object)
-{
- struct fscache_cookie *cookie = object->cookie;
- return atomic_inc_not_zero(&cookie->n_active) != 0;
-}
-
-static inline bool __fscache_unuse_cookie(struct fscache_cookie *cookie)
-{
- return atomic_dec_and_test(&cookie->n_active);
-}
-
-static inline void __fscache_wake_unused_cookie(struct fscache_cookie *cookie)
-{
- wake_up_var(&cookie->n_active);
-}
-
-/**
- * fscache_unuse_cookie - Cease usage of cookie attached to an object
- * @object: Object description
- *
- * Cease usage of the cookie attached to an object. When the users count
- * reaches zero then the cookie relinquishment will be permitted to proceed.
- */
-static inline void fscache_unuse_cookie(struct fscache_object *object)
-{
- struct fscache_cookie *cookie = object->cookie;
- if (__fscache_unuse_cookie(cookie))
- __fscache_wake_unused_cookie(cookie);
-}
-
-/*
- * out-of-line cache backend functions
- */
-extern __printf(3, 4)
-void fscache_init_cache(struct fscache_cache *cache,
- const struct fscache_cache_ops *ops,
- const char *idfmt, ...);
-
-extern int fscache_add_cache(struct fscache_cache *cache,
- struct fscache_object *fsdef,
- const char *tagname);
-extern void fscache_withdraw_cache(struct fscache_cache *cache);
-
-extern void fscache_io_error(struct fscache_cache *cache);
-
-extern void fscache_mark_page_cached(struct fscache_retrieval *op,
- struct page *page);
-
-extern void fscache_mark_pages_cached(struct fscache_retrieval *op,
- struct pagevec *pagevec);
-
-extern bool fscache_object_sleep_till_congested(signed long *timeoutp);
-
-extern enum fscache_checkaux fscache_check_aux(struct fscache_object *object,
- const void *data,
- uint16_t datalen,
- loff_t object_size);
-
-extern void fscache_object_retrying_stale(struct fscache_object *object);
-
-enum fscache_why_object_killed {
- FSCACHE_OBJECT_IS_STALE,
- FSCACHE_OBJECT_NO_SPACE,
- FSCACHE_OBJECT_WAS_RETIRED,
- FSCACHE_OBJECT_WAS_CULLED,
-};
-extern void fscache_object_mark_killed(struct fscache_object *object,
- enum fscache_why_object_killed why);
#endif /* _LINUX_FSCACHE_CACHE_H */
#define _LINUX_FSCACHE_H
#include <linux/fs.h>
-#include <linux/list.h>
-#include <linux/pagemap.h>
-#include <linux/pagevec.h>
-#include <linux/list_bl.h>
#include <linux/netfs.h>
#if defined(CONFIG_FSCACHE) || defined(CONFIG_FSCACHE_MODULE)
-#define fscache_available() (1)
#define fscache_cookie_valid(cookie) (cookie)
+#define fscache_cookie_enabled(cookie) (cookie)
#else
-#define fscache_available() (0)
#define fscache_cookie_valid(cookie) (0)
+#define fscache_cookie_enabled(cookie) (0)
#endif
-
-/* pattern used to fill dead space in an index entry */
-#define FSCACHE_INDEX_DEADFILL_PATTERN 0x79
-
-struct pagevec;
-struct fscache_cache_tag;
-struct fscache_cookie;
-struct fscache_netfs;
-struct netfs_read_request;
-
-typedef void (*fscache_rw_complete_t)(struct page *page,
- void *context,
- int error);
-
-/* result of index entry consultation */
-enum fscache_checkaux {
- FSCACHE_CHECKAUX_OKAY, /* entry okay as is */
- FSCACHE_CHECKAUX_NEEDS_UPDATE, /* entry requires update */
- FSCACHE_CHECKAUX_OBSOLETE, /* entry requires deletion */
-};
-
-/*
- * fscache cookie definition
- */
-struct fscache_cookie_def {
- /* name of cookie type */
- char name[16];
-
- /* cookie type */
- uint8_t type;
-#define FSCACHE_COOKIE_TYPE_INDEX 0
-#define FSCACHE_COOKIE_TYPE_DATAFILE 1
-
- /* select the cache into which to insert an entry in this index
- * - optional
- * - should return a cache identifier or NULL to cause the cache to be
- * inherited from the parent if possible or the first cache picked
- * for a non-index file if not
- */
- struct fscache_cache_tag *(*select_cache)(
- const void *parent_netfs_data,
- const void *cookie_netfs_data);
-
- /* consult the netfs about the state of an object
- * - this function can be absent if the index carries no state data
- * - the netfs data from the cookie being used as the target is
- * presented, as is the auxiliary data and the object size
- */
- enum fscache_checkaux (*check_aux)(void *cookie_netfs_data,
- const void *data,
- uint16_t datalen,
- loff_t object_size);
-
- /* get an extra reference on a read context
- * - this function can be absent if the completion function doesn't
- * require a context
- */
- void (*get_context)(void *cookie_netfs_data, void *context);
-
- /* release an extra reference on a read context
- * - this function can be absent if the completion function doesn't
- * require a context
- */
- void (*put_context)(void *cookie_netfs_data, void *context);
-
- /* indicate page that now have cache metadata retained
- * - this function should mark the specified page as now being cached
- * - the page will have been marked with PG_fscache before this is
- * called, so this is optional
- */
- void (*mark_page_cached)(void *cookie_netfs_data,
- struct address_space *mapping,
- struct page *page);
-};
-
-/*
- * fscache cached network filesystem type
- * - name, version and ops must be filled in before registration
- * - all other fields will be set during registration
- */
-struct fscache_netfs {
- uint32_t version; /* indexing version */
- const char *name; /* filesystem name */
- struct fscache_cookie *primary_index;
-};
-
-/*
- * data file or index object cookie
- * - a file will only appear in one cache
- * - a request to cache a file may or may not be honoured, subject to
- * constraints such as disk space
- * - indices are created on disk just-in-time
- */
-struct fscache_cookie {
- refcount_t ref; /* number of users of this cookie */
- atomic_t n_children; /* number of children of this cookie */
- atomic_t n_active; /* number of active users of netfs ptrs */
- unsigned int debug_id;
- spinlock_t lock;
- spinlock_t stores_lock; /* lock on page store tree */
- struct hlist_head backing_objects; /* object(s) backing this file/index */
- const struct fscache_cookie_def *def; /* definition */
- struct fscache_cookie *parent; /* parent of this entry */
- struct hlist_bl_node hash_link; /* Link in hash table */
- struct list_head proc_link; /* Link in proc list */
- void *netfs_data; /* back pointer to netfs */
- struct radix_tree_root stores; /* pages to be stored on this cookie */
-#define FSCACHE_COOKIE_PENDING_TAG 0 /* pages tag: pending write to cache */
-#define FSCACHE_COOKIE_STORING_TAG 1 /* pages tag: writing to cache */
-
- unsigned long flags;
-#define FSCACHE_COOKIE_LOOKING_UP 0 /* T if non-index cookie being looked up still */
-#define FSCACHE_COOKIE_NO_DATA_YET 1 /* T if new object with no cached data yet */
-#define FSCACHE_COOKIE_UNAVAILABLE 2 /* T if cookie is unavailable (error, etc) */
-#define FSCACHE_COOKIE_INVALIDATING 3 /* T if cookie is being invalidated */
-#define FSCACHE_COOKIE_RELINQUISHED 4 /* T if cookie has been relinquished */
-#define FSCACHE_COOKIE_ENABLED 5 /* T if cookie is enabled */
-#define FSCACHE_COOKIE_ENABLEMENT_LOCK 6 /* T if cookie is being en/disabled */
-#define FSCACHE_COOKIE_AUX_UPDATED 8 /* T if the auxiliary data was updated */
-#define FSCACHE_COOKIE_ACQUIRED 9 /* T if cookie is in use */
-#define FSCACHE_COOKIE_RELINQUISHING 10 /* T if cookie is being relinquished */
-
- u8 type; /* Type of object */
- u8 key_len; /* Length of index key */
- u8 aux_len; /* Length of auxiliary data */
- u32 key_hash; /* Hash of parent, type, key, len */
- union {
- void *key; /* Index key */
- u8 inline_key[16]; /* - If the key is short enough */
- };
- union {
- void *aux; /* Auxiliary data */
- u8 inline_aux[8]; /* - If the aux data is short enough */
- };
-};
-
-static inline bool fscache_cookie_enabled(struct fscache_cookie *cookie)
-{
- return fscache_cookie_valid(cookie) && test_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags);
-}
-
-/*
- * slow-path functions for when there is actually caching available, and the
- * netfs does actually have a valid token
- * - these are not to be called directly
- * - these are undefined symbols when FS-Cache is not configured and the
- * optimiser takes care of not using them
- */
-extern int __fscache_register_netfs(struct fscache_netfs *);
-extern void __fscache_unregister_netfs(struct fscache_netfs *);
-extern struct fscache_cache_tag *__fscache_lookup_cache_tag(const char *);
-extern void __fscache_release_cache_tag(struct fscache_cache_tag *);
-
-extern struct fscache_cookie *__fscache_acquire_cookie(
- struct fscache_cookie *,
- const struct fscache_cookie_def *,
- const void *, size_t,
- const void *, size_t,
- void *, loff_t, bool);
-extern void __fscache_relinquish_cookie(struct fscache_cookie *, const void *, bool);
-extern int __fscache_check_consistency(struct fscache_cookie *, const void *);
-extern void __fscache_update_cookie(struct fscache_cookie *, const void *);
-extern int __fscache_attr_changed(struct fscache_cookie *);
-extern void __fscache_invalidate(struct fscache_cookie *);
-extern void __fscache_wait_on_invalidate(struct fscache_cookie *);
-
-#ifdef FSCACHE_USE_NEW_IO_API
-extern int __fscache_begin_read_operation(struct netfs_read_request *, struct fscache_cookie *);
-#else
-extern int __fscache_read_or_alloc_page(struct fscache_cookie *,
- struct page *,
- fscache_rw_complete_t,
- void *,
- gfp_t);
-extern int __fscache_read_or_alloc_pages(struct fscache_cookie *,
- struct address_space *,
- struct list_head *,
- unsigned *,
- fscache_rw_complete_t,
- void *,
- gfp_t);
-extern int __fscache_alloc_page(struct fscache_cookie *, struct page *, gfp_t);
-extern int __fscache_write_page(struct fscache_cookie *, struct page *, loff_t, gfp_t);
-extern void __fscache_uncache_page(struct fscache_cookie *, struct page *);
-extern bool __fscache_check_page_write(struct fscache_cookie *, struct page *);
-extern void __fscache_wait_on_page_write(struct fscache_cookie *, struct page *);
-extern bool __fscache_maybe_release_page(struct fscache_cookie *, struct page *,
- gfp_t);
-extern void __fscache_uncache_all_inode_pages(struct fscache_cookie *,
- struct inode *);
-extern void __fscache_readpages_cancel(struct fscache_cookie *cookie,
- struct list_head *pages);
-#endif /* FSCACHE_USE_NEW_IO_API */
-
-extern void __fscache_disable_cookie(struct fscache_cookie *, const void *, bool);
-extern void __fscache_enable_cookie(struct fscache_cookie *, const void *, loff_t,
- bool (*)(void *), void *);
-
-/**
- * fscache_register_netfs - Register a filesystem as desiring caching services
- * @netfs: The description of the filesystem
- *
- * Register a filesystem as desiring caching services if they're available.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-int fscache_register_netfs(struct fscache_netfs *netfs)
-{
- if (fscache_available())
- return __fscache_register_netfs(netfs);
- else
- return 0;
-}
-
-/**
- * fscache_unregister_netfs - Indicate that a filesystem no longer desires
- * caching services
- * @netfs: The description of the filesystem
- *
- * Indicate that a filesystem no longer desires caching services for the
- * moment.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-void fscache_unregister_netfs(struct fscache_netfs *netfs)
-{
- if (fscache_available())
- __fscache_unregister_netfs(netfs);
-}
-
-/**
- * fscache_lookup_cache_tag - Look up a cache tag
- * @name: The name of the tag to search for
- *
- * Acquire a specific cache referral tag that can be used to select a specific
- * cache in which to cache an index.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-struct fscache_cache_tag *fscache_lookup_cache_tag(const char *name)
-{
- if (fscache_available())
- return __fscache_lookup_cache_tag(name);
- else
- return NULL;
-}
-
-/**
- * fscache_release_cache_tag - Release a cache tag
- * @tag: The tag to release
- *
- * Release a reference to a cache referral tag previously looked up.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-void fscache_release_cache_tag(struct fscache_cache_tag *tag)
-{
- if (fscache_available())
- __fscache_release_cache_tag(tag);
-}
-
-/**
- * fscache_acquire_cookie - Acquire a cookie to represent a cache object
- * @parent: The cookie that's to be the parent of this one
- * @def: A description of the cache object, including callback operations
- * @index_key: The index key for this cookie
- * @index_key_len: Size of the index key
- * @aux_data: The auxiliary data for the cookie (may be NULL)
- * @aux_data_len: Size of the auxiliary data buffer
- * @netfs_data: An arbitrary piece of data to be kept in the cookie to
- * represent the cache object to the netfs
- * @object_size: The initial size of object
- * @enable: Whether or not to enable a data cookie immediately
- *
- * This function is used to inform FS-Cache about part of an index hierarchy
- * that can be used to locate files. This is done by requesting a cookie for
- * each index in the path to the file.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-struct fscache_cookie *fscache_acquire_cookie(
- struct fscache_cookie *parent,
- const struct fscache_cookie_def *def,
- const void *index_key,
- size_t index_key_len,
- const void *aux_data,
- size_t aux_data_len,
- void *netfs_data,
- loff_t object_size,
- bool enable)
-{
- if (fscache_cookie_valid(parent) && fscache_cookie_enabled(parent))
- return __fscache_acquire_cookie(parent, def,
- index_key, index_key_len,
- aux_data, aux_data_len,
- netfs_data, object_size, enable);
- else
- return NULL;
-}
-
-/**
- * fscache_relinquish_cookie - Return the cookie to the cache, maybe discarding
- * it
- * @cookie: The cookie being returned
- * @aux_data: The updated auxiliary data for the cookie (may be NULL)
- * @retire: True if the cache object the cookie represents is to be discarded
- *
- * This function returns a cookie to the cache, forcibly discarding the
- * associated cache object if retire is set to true. The opportunity is
- * provided to update the auxiliary data in the cache before the object is
- * disconnected.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-void fscache_relinquish_cookie(struct fscache_cookie *cookie,
- const void *aux_data,
- bool retire)
-{
- if (fscache_cookie_valid(cookie))
- __fscache_relinquish_cookie(cookie, aux_data, retire);
-}
-
-/**
- * fscache_check_consistency - Request validation of a cache's auxiliary data
- * @cookie: The cookie representing the cache object
- * @aux_data: The updated auxiliary data for the cookie (may be NULL)
- *
- * Request an consistency check from fscache, which passes the request to the
- * backing cache. The auxiliary data on the cookie will be updated first if
- * @aux_data is set.
- *
- * Returns 0 if consistent and -ESTALE if inconsistent. May also
- * return -ENOMEM and -ERESTARTSYS.
- */
-static inline
-int fscache_check_consistency(struct fscache_cookie *cookie,
- const void *aux_data)
-{
- if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
- return __fscache_check_consistency(cookie, aux_data);
- else
- return 0;
-}
-
-/**
- * fscache_update_cookie - Request that a cache object be updated
- * @cookie: The cookie representing the cache object
- * @aux_data: The updated auxiliary data for the cookie (may be NULL)
- *
- * Request an update of the index data for the cache object associated with the
- * cookie. The auxiliary data on the cookie will be updated first if @aux_data
- * is set.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-void fscache_update_cookie(struct fscache_cookie *cookie, const void *aux_data)
-{
- if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
- __fscache_update_cookie(cookie, aux_data);
-}
-
-/**
- * fscache_pin_cookie - Pin a data-storage cache object in its cache
- * @cookie: The cookie representing the cache object
- *
- * Permit data-storage cache objects to be pinned in the cache.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-int fscache_pin_cookie(struct fscache_cookie *cookie)
-{
- return -ENOBUFS;
-}
-
-/**
- * fscache_pin_cookie - Unpin a data-storage cache object in its cache
- * @cookie: The cookie representing the cache object
- *
- * Permit data-storage cache objects to be unpinned from the cache.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-void fscache_unpin_cookie(struct fscache_cookie *cookie)
-{
-}
-
-/**
- * fscache_attr_changed - Notify cache that an object's attributes changed
- * @cookie: The cookie representing the cache object
- *
- * Send a notification to the cache indicating that an object's attributes have
- * changed. This includes the data size. These attributes will be obtained
- * through the get_attr() cookie definition op.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-int fscache_attr_changed(struct fscache_cookie *cookie)
-{
- if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
- return __fscache_attr_changed(cookie);
- else
- return -ENOBUFS;
-}
-
-/**
- * fscache_invalidate - Notify cache that an object needs invalidation
- * @cookie: The cookie representing the cache object
- *
- * Notify the cache that an object is needs to be invalidated and that it
- * should abort any retrievals or stores it is doing on the cache. The object
- * is then marked non-caching until such time as the invalidation is complete.
- *
- * This can be called with spinlocks held.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-void fscache_invalidate(struct fscache_cookie *cookie)
-{
- if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
- __fscache_invalidate(cookie);
-}
-
-/**
- * fscache_wait_on_invalidate - Wait for invalidation to complete
- * @cookie: The cookie representing the cache object
- *
- * Wait for the invalidation of an object to complete.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-void fscache_wait_on_invalidate(struct fscache_cookie *cookie)
-{
- if (fscache_cookie_valid(cookie))
- __fscache_wait_on_invalidate(cookie);
-}
-
-/**
- * fscache_reserve_space - Reserve data space for a cached object
- * @cookie: The cookie representing the cache object
- * @i_size: The amount of space to be reserved
- *
- * Reserve an amount of space in the cache for the cache object attached to a
- * cookie so that a write to that object within the space can always be
- * honoured.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-int fscache_reserve_space(struct fscache_cookie *cookie, loff_t size)
-{
- return -ENOBUFS;
-}
-
-#ifdef FSCACHE_USE_NEW_IO_API
-
-/**
- * fscache_begin_read_operation - Begin a read operation for the netfs lib
- * @rreq: The read request being undertaken
- * @cookie: The cookie representing the cache object
- *
- * Begin a read operation on behalf of the netfs helper library. @rreq
- * indicates the read request to which the operation state should be attached;
- * @cookie indicates the cache object that will be accessed.
- *
- * This is intended to be called from the ->begin_cache_operation() netfs lib
- * operation as implemented by the network filesystem.
- *
- * Returns:
- * * 0 - Success
- * * -ENOBUFS - No caching available
- * * Other error code from the cache, such as -ENOMEM.
- */
-static inline
-int fscache_begin_read_operation(struct netfs_read_request *rreq,
- struct fscache_cookie *cookie)
-{
- if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
- return __fscache_begin_read_operation(rreq, cookie);
- return -ENOBUFS;
-}
-
-#else /* FSCACHE_USE_NEW_IO_API */
-
-/**
- * fscache_read_or_alloc_page - Read a page from the cache or allocate a block
- * in which to store it
- * @cookie: The cookie representing the cache object
- * @page: The netfs page to fill if possible
- * @end_io_func: The callback to invoke when and if the page is filled
- * @context: An arbitrary piece of data to pass on to end_io_func()
- * @gfp: The conditions under which memory allocation should be made
- *
- * Read a page from the cache, or if that's not possible make a potential
- * one-block reservation in the cache into which the page may be stored once
- * fetched from the server.
- *
- * If the page is not backed by the cache object, or if it there's some reason
- * it can't be, -ENOBUFS will be returned and nothing more will be done for
- * that page.
- *
- * Else, if that page is backed by the cache, a read will be initiated directly
- * to the netfs's page and 0 will be returned by this function. The
- * end_io_func() callback will be invoked when the operation terminates on a
- * completion or failure. Note that the callback may be invoked before the
- * return.
- *
- * Else, if the page is unbacked, -ENODATA is returned and a block may have
- * been allocated in the cache.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-int fscache_read_or_alloc_page(struct fscache_cookie *cookie,
- struct page *page,
- fscache_rw_complete_t end_io_func,
- void *context,
- gfp_t gfp)
-{
- if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
- return __fscache_read_or_alloc_page(cookie, page, end_io_func,
- context, gfp);
- else
- return -ENOBUFS;
-}
-
-/**
- * fscache_read_or_alloc_pages - Read pages from the cache and/or allocate
- * blocks in which to store them
- * @cookie: The cookie representing the cache object
- * @mapping: The netfs inode mapping to which the pages will be attached
- * @pages: A list of potential netfs pages to be filled
- * @nr_pages: Number of pages to be read and/or allocated
- * @end_io_func: The callback to invoke when and if each page is filled
- * @context: An arbitrary piece of data to pass on to end_io_func()
- * @gfp: The conditions under which memory allocation should be made
- *
- * Read a set of pages from the cache, or if that's not possible, attempt to
- * make a potential one-block reservation for each page in the cache into which
- * that page may be stored once fetched from the server.
- *
- * If some pages are not backed by the cache object, or if it there's some
- * reason they can't be, -ENOBUFS will be returned and nothing more will be
- * done for that pages.
- *
- * Else, if some of the pages are backed by the cache, a read will be initiated
- * directly to the netfs's page and 0 will be returned by this function. The
- * end_io_func() callback will be invoked when the operation terminates on a
- * completion or failure. Note that the callback may be invoked before the
- * return.
- *
- * Else, if a page is unbacked, -ENODATA is returned and a block may have
- * been allocated in the cache.
- *
- * Because the function may want to return all of -ENOBUFS, -ENODATA and 0 in
- * regard to different pages, the return values are prioritised in that order.
- * Any pages submitted for reading are removed from the pages list.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-int fscache_read_or_alloc_pages(struct fscache_cookie *cookie,
- struct address_space *mapping,
- struct list_head *pages,
- unsigned *nr_pages,
- fscache_rw_complete_t end_io_func,
- void *context,
- gfp_t gfp)
-{
- if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
- return __fscache_read_or_alloc_pages(cookie, mapping, pages,
- nr_pages, end_io_func,
- context, gfp);
- else
- return -ENOBUFS;
-}
-
-/**
- * fscache_alloc_page - Allocate a block in which to store a page
- * @cookie: The cookie representing the cache object
- * @page: The netfs page to allocate a page for
- * @gfp: The conditions under which memory allocation should be made
- *
- * Request Allocation a block in the cache in which to store a netfs page
- * without retrieving any contents from the cache.
- *
- * If the page is not backed by a file then -ENOBUFS will be returned and
- * nothing more will be done, and no reservation will be made.
- *
- * Else, a block will be allocated if one wasn't already, and 0 will be
- * returned
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-int fscache_alloc_page(struct fscache_cookie *cookie,
- struct page *page,
- gfp_t gfp)
-{
- if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
- return __fscache_alloc_page(cookie, page, gfp);
- else
- return -ENOBUFS;
-}
-
-/**
- * fscache_readpages_cancel - Cancel read/alloc on pages
- * @cookie: The cookie representing the inode's cache object.
- * @pages: The netfs pages that we canceled write on in readpages()
- *
- * Uncache/unreserve the pages reserved earlier in readpages() via
- * fscache_readpages_or_alloc() and similar. In most successful caches in
- * readpages() this doesn't do anything. In cases when the underlying netfs's
- * readahead failed we need to clean up the pagelist (unmark and uncache).
- *
- * This function may sleep as it may have to clean up disk state.
- */
-static inline
-void fscache_readpages_cancel(struct fscache_cookie *cookie,
- struct list_head *pages)
-{
- if (fscache_cookie_valid(cookie))
- __fscache_readpages_cancel(cookie, pages);
-}
-
-/**
- * fscache_write_page - Request storage of a page in the cache
- * @cookie: The cookie representing the cache object
- * @page: The netfs page to store
- * @object_size: Updated size of object
- * @gfp: The conditions under which memory allocation should be made
- *
- * Request the contents of the netfs page be written into the cache. This
- * request may be ignored if no cache block is currently allocated, in which
- * case it will return -ENOBUFS.
- *
- * If a cache block was already allocated, a write will be initiated and 0 will
- * be returned. The PG_fscache_write page bit is set immediately and will then
- * be cleared at the completion of the write to indicate the success or failure
- * of the operation. Note that the completion may happen before the return.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-int fscache_write_page(struct fscache_cookie *cookie,
- struct page *page,
- loff_t object_size,
- gfp_t gfp)
-{
- if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
- return __fscache_write_page(cookie, page, object_size, gfp);
- else
- return -ENOBUFS;
-}
-
-/**
- * fscache_uncache_page - Indicate that caching is no longer required on a page
- * @cookie: The cookie representing the cache object
- * @page: The netfs page that was being cached.
- *
- * Tell the cache that we no longer want a page to be cached and that it should
- * remove any knowledge of the netfs page it may have.
- *
- * Note that this cannot cancel any outstanding I/O operations between this
- * page and the cache.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-void fscache_uncache_page(struct fscache_cookie *cookie,
- struct page *page)
-{
- if (fscache_cookie_valid(cookie))
- __fscache_uncache_page(cookie, page);
-}
-
-/**
- * fscache_check_page_write - Ask if a page is being writing to the cache
- * @cookie: The cookie representing the cache object
- * @page: The netfs page that is being cached.
- *
- * Ask the cache if a page is being written to the cache.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-bool fscache_check_page_write(struct fscache_cookie *cookie,
- struct page *page)
-{
- if (fscache_cookie_valid(cookie))
- return __fscache_check_page_write(cookie, page);
- return false;
-}
-
-/**
- * fscache_wait_on_page_write - Wait for a page to complete writing to the cache
- * @cookie: The cookie representing the cache object
- * @page: The netfs page that is being cached.
- *
- * Ask the cache to wake us up when a page is no longer being written to the
- * cache.
- *
- * See Documentation/filesystems/caching/netfs-api.rst for a complete
- * description.
- */
-static inline
-void fscache_wait_on_page_write(struct fscache_cookie *cookie,
- struct page *page)
-{
- if (fscache_cookie_valid(cookie))
- __fscache_wait_on_page_write(cookie, page);
-}
-
-/**
- * fscache_maybe_release_page - Consider releasing a page, cancelling a store
- * @cookie: The cookie representing the cache object
- * @page: The netfs page that is being cached.
- * @gfp: The gfp flags passed to releasepage()
- *
- * Consider releasing a page for the vmscan algorithm, on behalf of the netfs's
- * releasepage() call. A storage request on the page may cancelled if it is
- * not currently being processed.
- *
- * The function returns true if the page no longer has a storage request on it,
- * and false if a storage request is left in place. If true is returned, the
- * page will have been passed to fscache_uncache_page(). If false is returned
- * the page cannot be freed yet.
- */
-static inline
-bool fscache_maybe_release_page(struct fscache_cookie *cookie,
- struct page *page,
- gfp_t gfp)
-{
- if (fscache_cookie_valid(cookie) && PageFsCache(page))
- return __fscache_maybe_release_page(cookie, page, gfp);
- return true;
-}
-
-/**
- * fscache_uncache_all_inode_pages - Uncache all an inode's pages
- * @cookie: The cookie representing the inode's cache object.
- * @inode: The inode to uncache pages from.
- *
- * Uncache all the pages in an inode that are marked PG_fscache, assuming them
- * to be associated with the given cookie.
- *
- * This function may sleep. It will wait for pages that are being written out
- * and will wait whilst the PG_fscache mark is removed by the cache.
- */
-static inline
-void fscache_uncache_all_inode_pages(struct fscache_cookie *cookie,
- struct inode *inode)
-{
- if (fscache_cookie_valid(cookie))
- __fscache_uncache_all_inode_pages(cookie, inode);
-}
-
-#endif /* FSCACHE_USE_NEW_IO_API */
-
-/**
- * fscache_disable_cookie - Disable a cookie
- * @cookie: The cookie representing the cache object
- * @aux_data: The updated auxiliary data for the cookie (may be NULL)
- * @invalidate: Invalidate the backing object
- *
- * Disable a cookie from accepting further alloc, read, write, invalidate,
- * update or acquire operations. Outstanding operations can still be waited
- * upon and pages can still be uncached and the cookie relinquished.
- *
- * This will not return until all outstanding operations have completed.
- *
- * If @invalidate is set, then the backing object will be invalidated and
- * detached, otherwise it will just be detached.
- *
- * If @aux_data is set, then auxiliary data will be updated from that.
- */
-static inline
-void fscache_disable_cookie(struct fscache_cookie *cookie,
- const void *aux_data,
- bool invalidate)
-{
- if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
- __fscache_disable_cookie(cookie, aux_data, invalidate);
-}
-
-/**
- * fscache_enable_cookie - Reenable a cookie
- * @cookie: The cookie representing the cache object
- * @aux_data: The updated auxiliary data for the cookie (may be NULL)
- * @object_size: Current size of object
- * @can_enable: A function to permit enablement once lock is held
- * @data: Data for can_enable()
- *
- * Reenable a previously disabled cookie, allowing it to accept further alloc,
- * read, write, invalidate, update or acquire operations. An attempt will be
- * made to immediately reattach the cookie to a backing object. If @aux_data
- * is set, the auxiliary data attached to the cookie will be updated.
- *
- * The can_enable() function is called (if not NULL) once the enablement lock
- * is held to rule on whether enablement is still permitted to go ahead.
- */
-static inline
-void fscache_enable_cookie(struct fscache_cookie *cookie,
- const void *aux_data,
- loff_t object_size,
- bool (*can_enable)(void *data),
- void *data)
-{
- if (fscache_cookie_valid(cookie) && !fscache_cookie_enabled(cookie))
- __fscache_enable_cookie(cookie, aux_data, object_size,
- can_enable, data);
-}
-
#endif /* _LINUX_FSCACHE_H */
+++ /dev/null
-/* SPDX-License-Identifier: GPL-2.0-or-later */
-/* FS-Cache tracepoints
- *
- * Copyright (C) 2016 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- */
-#undef TRACE_SYSTEM
-#define TRACE_SYSTEM fscache
-
-#if !defined(_TRACE_FSCACHE_H) || defined(TRACE_HEADER_MULTI_READ)
-#define _TRACE_FSCACHE_H
-
-#include <linux/fscache.h>
-#include <linux/tracepoint.h>
-
-/*
- * Define enums for tracing information.
- */
-#ifndef __FSCACHE_DECLARE_TRACE_ENUMS_ONCE_ONLY
-#define __FSCACHE_DECLARE_TRACE_ENUMS_ONCE_ONLY
-
-enum fscache_cookie_trace {
- fscache_cookie_collision,
- fscache_cookie_discard,
- fscache_cookie_get_acquire_parent,
- fscache_cookie_get_attach_object,
- fscache_cookie_get_reacquire,
- fscache_cookie_get_register_netfs,
- fscache_cookie_put_acquire_nobufs,
- fscache_cookie_put_dup_netfs,
- fscache_cookie_put_relinquish,
- fscache_cookie_put_object,
- fscache_cookie_put_parent,
-};
-
-enum fscache_page_trace {
- fscache_page_cached,
- fscache_page_inval,
- fscache_page_maybe_release,
- fscache_page_radix_clear_store,
- fscache_page_radix_delete,
- fscache_page_radix_insert,
- fscache_page_radix_pend2store,
- fscache_page_radix_set_pend,
- fscache_page_uncache,
- fscache_page_write,
- fscache_page_write_end,
- fscache_page_write_end_pend,
- fscache_page_write_end_noc,
- fscache_page_write_wait,
- fscache_page_trace__nr
-};
-
-enum fscache_op_trace {
- fscache_op_cancel,
- fscache_op_cancel_all,
- fscache_op_cancelled,
- fscache_op_completed,
- fscache_op_enqueue_async,
- fscache_op_enqueue_mythread,
- fscache_op_gc,
- fscache_op_init,
- fscache_op_put,
- fscache_op_run,
- fscache_op_signal,
- fscache_op_submit,
- fscache_op_submit_ex,
- fscache_op_work,
- fscache_op_trace__nr
-};
-
-enum fscache_page_op_trace {
- fscache_page_op_alloc_one,
- fscache_page_op_attr_changed,
- fscache_page_op_check_consistency,
- fscache_page_op_invalidate,
- fscache_page_op_retr_multi,
- fscache_page_op_retr_one,
- fscache_page_op_write_one,
- fscache_page_op_trace__nr
-};
-
-#endif
-
-/*
- * Declare tracing information enums and their string mappings for display.
- */
-#define fscache_cookie_traces \
- EM(fscache_cookie_collision, "*COLLISION*") \
- EM(fscache_cookie_discard, "DISCARD") \
- EM(fscache_cookie_get_acquire_parent, "GET prn") \
- EM(fscache_cookie_get_attach_object, "GET obj") \
- EM(fscache_cookie_get_reacquire, "GET raq") \
- EM(fscache_cookie_get_register_netfs, "GET net") \
- EM(fscache_cookie_put_acquire_nobufs, "PUT nbf") \
- EM(fscache_cookie_put_dup_netfs, "PUT dnt") \
- EM(fscache_cookie_put_relinquish, "PUT rlq") \
- EM(fscache_cookie_put_object, "PUT obj") \
- E_(fscache_cookie_put_parent, "PUT prn")
-
-#define fscache_page_traces \
- EM(fscache_page_cached, "Cached ") \
- EM(fscache_page_inval, "InvalPg") \
- EM(fscache_page_maybe_release, "MayRels") \
- EM(fscache_page_uncache, "Uncache") \
- EM(fscache_page_radix_clear_store, "RxCStr ") \
- EM(fscache_page_radix_delete, "RxDel ") \
- EM(fscache_page_radix_insert, "RxIns ") \
- EM(fscache_page_radix_pend2store, "RxP2S ") \
- EM(fscache_page_radix_set_pend, "RxSPend ") \
- EM(fscache_page_write, "WritePg") \
- EM(fscache_page_write_end, "EndPgWr") \
- EM(fscache_page_write_end_pend, "EndPgWP") \
- EM(fscache_page_write_end_noc, "EndPgNC") \
- E_(fscache_page_write_wait, "WtOnWrt")
-
-#define fscache_op_traces \
- EM(fscache_op_cancel, "Cancel1") \
- EM(fscache_op_cancel_all, "CancelA") \
- EM(fscache_op_cancelled, "Canclld") \
- EM(fscache_op_completed, "Complet") \
- EM(fscache_op_enqueue_async, "EnqAsyn") \
- EM(fscache_op_enqueue_mythread, "EnqMyTh") \
- EM(fscache_op_gc, "GC ") \
- EM(fscache_op_init, "Init ") \
- EM(fscache_op_put, "Put ") \
- EM(fscache_op_run, "Run ") \
- EM(fscache_op_signal, "Signal ") \
- EM(fscache_op_submit, "Submit ") \
- EM(fscache_op_submit_ex, "SubmitX") \
- E_(fscache_op_work, "Work ")
-
-#define fscache_page_op_traces \
- EM(fscache_page_op_alloc_one, "Alloc1 ") \
- EM(fscache_page_op_attr_changed, "AttrChg") \
- EM(fscache_page_op_check_consistency, "CheckCn") \
- EM(fscache_page_op_invalidate, "Inval ") \
- EM(fscache_page_op_retr_multi, "RetrMul") \
- EM(fscache_page_op_retr_one, "Retr1 ") \
- E_(fscache_page_op_write_one, "Write1 ")
-
-/*
- * Export enum symbols via userspace.
- */
-#undef EM
-#undef E_
-#define EM(a, b) TRACE_DEFINE_ENUM(a);
-#define E_(a, b) TRACE_DEFINE_ENUM(a);
-
-fscache_cookie_traces;
-
-/*
- * Now redefine the EM() and E_() macros to map the enums to the strings that
- * will be printed in the output.
- */
-#undef EM
-#undef E_
-#define EM(a, b) { a, b },
-#define E_(a, b) { a, b }
-
-
-TRACE_EVENT(fscache_cookie,
- TP_PROTO(unsigned int cookie_debug_id,
- int ref,
- enum fscache_cookie_trace where),
-
- TP_ARGS(cookie_debug_id, ref, where),
-
- TP_STRUCT__entry(
- __field(unsigned int, cookie )
- __field(enum fscache_cookie_trace, where )
- __field(int, ref )
- ),
-
- TP_fast_assign(
- __entry->cookie = cookie_debug_id;
- __entry->where = where;
- __entry->ref = ref;
- ),
-
- TP_printk("%s c=%08x r=%d",
- __print_symbolic(__entry->where, fscache_cookie_traces),
- __entry->cookie, __entry->ref)
- );
-
-TRACE_EVENT(fscache_netfs,
- TP_PROTO(struct fscache_netfs *netfs),
-
- TP_ARGS(netfs),
-
- TP_STRUCT__entry(
- __field(unsigned int, cookie )
- __array(char, name, 8 )
- ),
-
- TP_fast_assign(
- __entry->cookie = netfs->primary_index->debug_id;
- strncpy(__entry->name, netfs->name, 8);
- __entry->name[7] = 0;
- ),
-
- TP_printk("c=%08x n=%s",
- __entry->cookie, __entry->name)
- );
-
-TRACE_EVENT(fscache_acquire,
- TP_PROTO(struct fscache_cookie *cookie),
-
- TP_ARGS(cookie),
-
- TP_STRUCT__entry(
- __field(unsigned int, cookie )
- __field(unsigned int, parent )
- __array(char, name, 8 )
- __field(int, p_ref )
- __field(int, p_n_children )
- __field(u8, p_flags )
- ),
-
- TP_fast_assign(
- __entry->cookie = cookie->debug_id;
- __entry->parent = cookie->parent->debug_id;
- __entry->p_ref = refcount_read(&cookie->parent->ref);
- __entry->p_n_children = atomic_read(&cookie->parent->n_children);
- __entry->p_flags = cookie->parent->flags;
- memcpy(__entry->name, cookie->def->name, 8);
- __entry->name[7] = 0;
- ),
-
- TP_printk("c=%08x p=%08x pr=%d pc=%d pf=%02x n=%s",
- __entry->cookie, __entry->parent, __entry->p_ref,
- __entry->p_n_children, __entry->p_flags, __entry->name)
- );
-
-TRACE_EVENT(fscache_relinquish,
- TP_PROTO(struct fscache_cookie *cookie, bool retire),
-
- TP_ARGS(cookie, retire),
-
- TP_STRUCT__entry(
- __field(unsigned int, cookie )
- __field(unsigned int, parent )
- __field(int, ref )
- __field(int, n_children )
- __field(int, n_active )
- __field(u8, flags )
- __field(bool, retire )
- ),
-
- TP_fast_assign(
- __entry->cookie = cookie->debug_id;
- __entry->parent = cookie->parent->debug_id;
- __entry->ref = refcount_read(&cookie->ref);
- __entry->n_children = atomic_read(&cookie->n_children);
- __entry->n_active = atomic_read(&cookie->n_active);
- __entry->flags = cookie->flags;
- __entry->retire = retire;
- ),
-
- TP_printk("c=%08x r=%d p=%08x Nc=%d Na=%d f=%02x r=%u",
- __entry->cookie, __entry->ref,
- __entry->parent, __entry->n_children, __entry->n_active,
- __entry->flags, __entry->retire)
- );
-
-TRACE_EVENT(fscache_enable,
- TP_PROTO(struct fscache_cookie *cookie),
-
- TP_ARGS(cookie),
-
- TP_STRUCT__entry(
- __field(unsigned int, cookie )
- __field(int, ref )
- __field(int, n_children )
- __field(int, n_active )
- __field(u8, flags )
- ),
-
- TP_fast_assign(
- __entry->cookie = cookie->debug_id;
- __entry->ref = refcount_read(&cookie->ref);
- __entry->n_children = atomic_read(&cookie->n_children);
- __entry->n_active = atomic_read(&cookie->n_active);
- __entry->flags = cookie->flags;
- ),
-
- TP_printk("c=%08x r=%d Nc=%d Na=%d f=%02x",
- __entry->cookie, __entry->ref,
- __entry->n_children, __entry->n_active, __entry->flags)
- );
-
-TRACE_EVENT(fscache_disable,
- TP_PROTO(struct fscache_cookie *cookie),
-
- TP_ARGS(cookie),
-
- TP_STRUCT__entry(
- __field(unsigned int, cookie )
- __field(int, ref )
- __field(int, n_children )
- __field(int, n_active )
- __field(u8, flags )
- ),
-
- TP_fast_assign(
- __entry->cookie = cookie->debug_id;
- __entry->ref = refcount_read(&cookie->ref);
- __entry->n_children = atomic_read(&cookie->n_children);
- __entry->n_active = atomic_read(&cookie->n_active);
- __entry->flags = cookie->flags;
- ),
-
- TP_printk("c=%08x r=%d Nc=%d Na=%d f=%02x",
- __entry->cookie, __entry->ref,
- __entry->n_children, __entry->n_active, __entry->flags)
- );
-
-TRACE_EVENT(fscache_osm,
- TP_PROTO(struct fscache_object *object,
- const struct fscache_state *state,
- bool wait, bool oob, s8 event_num),
-
- TP_ARGS(object, state, wait, oob, event_num),
-
- TP_STRUCT__entry(
- __field(unsigned int, cookie )
- __field(unsigned int, object )
- __array(char, state, 8 )
- __field(bool, wait )
- __field(bool, oob )
- __field(s8, event_num )
- ),
-
- TP_fast_assign(
- __entry->cookie = object->cookie->debug_id;
- __entry->object = object->debug_id;
- __entry->wait = wait;
- __entry->oob = oob;
- __entry->event_num = event_num;
- memcpy(__entry->state, state->short_name, 8);
- ),
-
- TP_printk("c=%08x o=%08d %s %s%sev=%d",
- __entry->cookie,
- __entry->object,
- __entry->state,
- __print_symbolic(__entry->wait,
- { true, "WAIT" },
- { false, "WORK" }),
- __print_symbolic(__entry->oob,
- { true, " OOB " },
- { false, " " }),
- __entry->event_num)
- );
-
-TRACE_EVENT(fscache_page,
- TP_PROTO(struct fscache_cookie *cookie, struct page *page,
- enum fscache_page_trace why),
-
- TP_ARGS(cookie, page, why),
-
- TP_STRUCT__entry(
- __field(unsigned int, cookie )
- __field(pgoff_t, page )
- __field(enum fscache_page_trace, why )
- ),
-
- TP_fast_assign(
- __entry->cookie = cookie->debug_id;
- __entry->page = page->index;
- __entry->why = why;
- ),
-
- TP_printk("c=%08x %s pg=%lx",
- __entry->cookie,
- __print_symbolic(__entry->why, fscache_page_traces),
- __entry->page)
- );
-
-TRACE_EVENT(fscache_check_page,
- TP_PROTO(struct fscache_cookie *cookie, struct page *page,
- void *val, int n),
-
- TP_ARGS(cookie, page, val, n),
-
- TP_STRUCT__entry(
- __field(unsigned int, cookie )
- __field(void *, page )
- __field(void *, val )
- __field(int, n )
- ),
-
- TP_fast_assign(
- __entry->cookie = cookie->debug_id;
- __entry->page = page;
- __entry->val = val;
- __entry->n = n;
- ),
-
- TP_printk("c=%08x pg=%p val=%p n=%d",
- __entry->cookie, __entry->page, __entry->val, __entry->n)
- );
-
-TRACE_EVENT(fscache_wake_cookie,
- TP_PROTO(struct fscache_cookie *cookie),
-
- TP_ARGS(cookie),
-
- TP_STRUCT__entry(
- __field(unsigned int, cookie )
- ),
-
- TP_fast_assign(
- __entry->cookie = cookie->debug_id;
- ),
-
- TP_printk("c=%08x", __entry->cookie)
- );
-
-TRACE_EVENT(fscache_op,
- TP_PROTO(struct fscache_cookie *cookie, struct fscache_operation *op,
- enum fscache_op_trace why),
-
- TP_ARGS(cookie, op, why),
-
- TP_STRUCT__entry(
- __field(unsigned int, cookie )
- __field(unsigned int, op )
- __field(enum fscache_op_trace, why )
- ),
-
- TP_fast_assign(
- __entry->cookie = cookie ? cookie->debug_id : 0;
- __entry->op = op->debug_id;
- __entry->why = why;
- ),
-
- TP_printk("c=%08x op=%08x %s",
- __entry->cookie, __entry->op,
- __print_symbolic(__entry->why, fscache_op_traces))
- );
-
-TRACE_EVENT(fscache_page_op,
- TP_PROTO(struct fscache_cookie *cookie, struct page *page,
- struct fscache_operation *op, enum fscache_page_op_trace what),
-
- TP_ARGS(cookie, page, op, what),
-
- TP_STRUCT__entry(
- __field(unsigned int, cookie )
- __field(unsigned int, op )
- __field(pgoff_t, page )
- __field(enum fscache_page_op_trace, what )
- ),
-
- TP_fast_assign(
- __entry->cookie = cookie->debug_id;
- __entry->page = page ? page->index : 0;
- __entry->op = op->debug_id;
- __entry->what = what;
- ),
-
- TP_printk("c=%08x %s pg=%lx op=%08x",
- __entry->cookie,
- __print_symbolic(__entry->what, fscache_page_op_traces),
- __entry->page, __entry->op)
- );
-
-TRACE_EVENT(fscache_wrote_page,
- TP_PROTO(struct fscache_cookie *cookie, struct page *page,
- struct fscache_operation *op, int ret),
-
- TP_ARGS(cookie, page, op, ret),
-
- TP_STRUCT__entry(
- __field(unsigned int, cookie )
- __field(unsigned int, op )
- __field(pgoff_t, page )
- __field(int, ret )
- ),
-
- TP_fast_assign(
- __entry->cookie = cookie->debug_id;
- __entry->page = page->index;
- __entry->op = op->debug_id;
- __entry->ret = ret;
- ),
-
- TP_printk("c=%08x pg=%lx op=%08x ret=%d",
- __entry->cookie, __entry->page, __entry->op, __entry->ret)
- );
-
-TRACE_EVENT(fscache_gang_lookup,
- TP_PROTO(struct fscache_cookie *cookie, struct fscache_operation *op,
- void **results, int n, pgoff_t store_limit),
-
- TP_ARGS(cookie, op, results, n, store_limit),
-
- TP_STRUCT__entry(
- __field(unsigned int, cookie )
- __field(unsigned int, op )
- __field(pgoff_t, results0 )
- __field(int, n )
- __field(pgoff_t, store_limit )
- ),
-
- TP_fast_assign(
- __entry->cookie = cookie->debug_id;
- __entry->op = op->debug_id;
- __entry->results0 = results[0] ? ((struct page *)results[0])->index : (pgoff_t)-1;
- __entry->n = n;
- __entry->store_limit = store_limit;
- ),
-
- TP_printk("c=%08x op=%08x r0=%lx n=%d sl=%lx",
- __entry->cookie, __entry->op, __entry->results0, __entry->n,
- __entry->store_limit)
- );
-
-#endif /* _TRACE_FSCACHE_H */
-
-/* This part must be outside protection */
-#include <trace/define_trace.h>