+++ /dev/null
-/*
- * fs/inotify.c - inode-based file event notifications
- *
- * Authors:
- * John McCutchan <ttb@tentacle.dhs.org>
- * Robert Love <rml@novell.com>
- *
- * Kernel API added by: Amy Griffis <amy.griffis@hp.com>
- *
- * Copyright (C) 2005 John McCutchan
- * Copyright 2006 Hewlett-Packard Development Company, L.P.
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the
- * Free Software Foundation; either version 2, or (at your option) any
- * later version.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- */
-
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/spinlock.h>
-#include <linux/idr.h>
-#include <linux/slab.h>
-#include <linux/fs.h>
-#include <linux/sched.h>
-#include <linux/init.h>
-#include <linux/list.h>
-#include <linux/writeback.h>
-#include <linux/inotify.h>
-#include <linux/fsnotify_backend.h>
-
-static atomic_t inotify_cookie;
-
-/*
- * Lock ordering:
- *
- * dentry->d_lock (used to keep d_move() away from dentry->d_parent)
- * iprune_mutex (synchronize shrink_icache_memory())
- * inode_lock (protects the super_block->s_inodes list)
- * inode->inotify_mutex (protects inode->inotify_watches and watches->i_list)
- * inotify_handle->mutex (protects inotify_handle and watches->h_list)
- *
- * The inode->inotify_mutex and inotify_handle->mutex and held during execution
- * of a caller's event handler. Thus, the caller must not hold any locks
- * taken in their event handler while calling any of the published inotify
- * interfaces.
- */
-
-/*
- * Lifetimes of the three main data structures--inotify_handle, inode, and
- * inotify_watch--are managed by reference count.
- *
- * inotify_handle: Lifetime is from inotify_init() to inotify_destroy().
- * Additional references can bump the count via get_inotify_handle() and drop
- * the count via put_inotify_handle().
- *
- * inotify_watch: for inotify's purposes, lifetime is from inotify_add_watch()
- * to remove_watch_no_event(). Additional references can bump the count via
- * get_inotify_watch() and drop the count via put_inotify_watch(). The caller
- * is reponsible for the final put after receiving IN_IGNORED, or when using
- * IN_ONESHOT after receiving the first event. Inotify does the final put if
- * inotify_destroy() is called.
- *
- * inode: Pinned so long as the inode is associated with a watch, from
- * inotify_add_watch() to the final put_inotify_watch().
- */
-
-/*
- * struct inotify_handle - represents an inotify instance
- *
- * This structure is protected by the mutex 'mutex'.
- */
-struct inotify_handle {
- struct idr idr; /* idr mapping wd -> watch */
- struct mutex mutex; /* protects this bad boy */
- struct list_head watches; /* list of watches */
- atomic_t count; /* reference count */
- u32 last_wd; /* the last wd allocated */
- const struct inotify_operations *in_ops; /* inotify caller operations */
-};
-
-static inline void get_inotify_handle(struct inotify_handle *ih)
-{
- atomic_inc(&ih->count);
-}
-
-static inline void put_inotify_handle(struct inotify_handle *ih)
-{
- if (atomic_dec_and_test(&ih->count)) {
- idr_destroy(&ih->idr);
- kfree(ih);
- }
-}
-
-/**
- * get_inotify_watch - grab a reference to an inotify_watch
- * @watch: watch to grab
- */
-void get_inotify_watch(struct inotify_watch *watch)
-{
- atomic_inc(&watch->count);
-}
-EXPORT_SYMBOL_GPL(get_inotify_watch);
-
-int pin_inotify_watch(struct inotify_watch *watch)
-{
- struct super_block *sb = watch->inode->i_sb;
- if (atomic_inc_not_zero(&sb->s_active)) {
- atomic_inc(&watch->count);
- return 1;
- }
- return 0;
-}
-
-/**
- * put_inotify_watch - decrements the ref count on a given watch. cleans up
- * watch references if the count reaches zero. inotify_watch is freed by
- * inotify callers via the destroy_watch() op.
- * @watch: watch to release
- */
-void put_inotify_watch(struct inotify_watch *watch)
-{
- if (atomic_dec_and_test(&watch->count)) {
- struct inotify_handle *ih = watch->ih;
-
- iput(watch->inode);
- ih->in_ops->destroy_watch(watch);
- put_inotify_handle(ih);
- }
-}
-EXPORT_SYMBOL_GPL(put_inotify_watch);
-
-void unpin_inotify_watch(struct inotify_watch *watch)
-{
- struct super_block *sb = watch->inode->i_sb;
- put_inotify_watch(watch);
- deactivate_super(sb);
-}
-
-/*
- * inotify_handle_get_wd - returns the next WD for use by the given handle
- *
- * Callers must hold ih->mutex. This function can sleep.
- */
-static int inotify_handle_get_wd(struct inotify_handle *ih,
- struct inotify_watch *watch)
-{
- int ret;
-
- do {
- if (unlikely(!idr_pre_get(&ih->idr, GFP_NOFS)))
- return -ENOSPC;
- ret = idr_get_new_above(&ih->idr, watch, ih->last_wd+1, &watch->wd);
- } while (ret == -EAGAIN);
-
- if (likely(!ret))
- ih->last_wd = watch->wd;
-
- return ret;
-}
-
-/*
- * inotify_inode_watched - returns nonzero if there are watches on this inode
- * and zero otherwise. We call this lockless, we do not care if we race.
- */
-static inline int inotify_inode_watched(struct inode *inode)
-{
- return !list_empty(&inode->inotify_watches);
-}
-
-/*
- * Get child dentry flag into synch with parent inode.
- * Flag should always be clear for negative dentrys.
- */
-static void set_dentry_child_flags(struct inode *inode, int watched)
-{
- struct dentry *alias;
-
- spin_lock(&dcache_lock);
- list_for_each_entry(alias, &inode->i_dentry, d_alias) {
- struct dentry *child;
-
- list_for_each_entry(child, &alias->d_subdirs, d_u.d_child) {
- if (!child->d_inode)
- continue;
-
- spin_lock(&child->d_lock);
- if (watched)
- child->d_flags |= DCACHE_INOTIFY_PARENT_WATCHED;
- else
- child->d_flags &=~DCACHE_INOTIFY_PARENT_WATCHED;
- spin_unlock(&child->d_lock);
- }
- }
- spin_unlock(&dcache_lock);
-}
-
-/*
- * inotify_find_handle - find the watch associated with the given inode and
- * handle
- *
- * Callers must hold inode->inotify_mutex.
- */
-static struct inotify_watch *inode_find_handle(struct inode *inode,
- struct inotify_handle *ih)
-{
- struct inotify_watch *watch;
-
- list_for_each_entry(watch, &inode->inotify_watches, i_list) {
- if (watch->ih == ih)
- return watch;
- }
-
- return NULL;
-}
-
-/*
- * remove_watch_no_event - remove watch without the IN_IGNORED event.
- *
- * Callers must hold both inode->inotify_mutex and ih->mutex.
- */
-static void remove_watch_no_event(struct inotify_watch *watch,
- struct inotify_handle *ih)
-{
- list_del(&watch->i_list);
- list_del(&watch->h_list);
-
- if (!inotify_inode_watched(watch->inode))
- set_dentry_child_flags(watch->inode, 0);
-
- idr_remove(&ih->idr, watch->wd);
-}
-
-/**
- * inotify_remove_watch_locked - Remove a watch from both the handle and the
- * inode. Sends the IN_IGNORED event signifying that the inode is no longer
- * watched. May be invoked from a caller's event handler.
- * @ih: inotify handle associated with watch
- * @watch: watch to remove
- *
- * Callers must hold both inode->inotify_mutex and ih->mutex.
- */
-void inotify_remove_watch_locked(struct inotify_handle *ih,
- struct inotify_watch *watch)
-{
- remove_watch_no_event(watch, ih);
- ih->in_ops->handle_event(watch, watch->wd, IN_IGNORED, 0, NULL, NULL);
-}
-EXPORT_SYMBOL_GPL(inotify_remove_watch_locked);
-
-/* Kernel API for producing events */
-
-/*
- * inotify_d_instantiate - instantiate dcache entry for inode
- */
-void inotify_d_instantiate(struct dentry *entry, struct inode *inode)
-{
- struct dentry *parent;
-
- if (!inode)
- return;
-
- spin_lock(&entry->d_lock);
- parent = entry->d_parent;
- if (parent->d_inode && inotify_inode_watched(parent->d_inode))
- entry->d_flags |= DCACHE_INOTIFY_PARENT_WATCHED;
- spin_unlock(&entry->d_lock);
-}
-
-/*
- * inotify_d_move - dcache entry has been moved
- */
-void inotify_d_move(struct dentry *entry)
-{
- struct dentry *parent;
-
- parent = entry->d_parent;
- if (inotify_inode_watched(parent->d_inode))
- entry->d_flags |= DCACHE_INOTIFY_PARENT_WATCHED;
- else
- entry->d_flags &= ~DCACHE_INOTIFY_PARENT_WATCHED;
-}
-
-/**
- * inotify_inode_queue_event - queue an event to all watches on this inode
- * @inode: inode event is originating from
- * @mask: event mask describing this event
- * @cookie: cookie for synchronization, or zero
- * @name: filename, if any
- * @n_inode: inode associated with name
- */
-void inotify_inode_queue_event(struct inode *inode, u32 mask, u32 cookie,
- const char *name, struct inode *n_inode)
-{
- struct inotify_watch *watch, *next;
-
- if (!inotify_inode_watched(inode))
- return;
-
- mutex_lock(&inode->inotify_mutex);
- list_for_each_entry_safe(watch, next, &inode->inotify_watches, i_list) {
- u32 watch_mask = watch->mask;
- if (watch_mask & mask) {
- struct inotify_handle *ih= watch->ih;
- mutex_lock(&ih->mutex);
- if (watch_mask & IN_ONESHOT)
- remove_watch_no_event(watch, ih);
- ih->in_ops->handle_event(watch, watch->wd, mask, cookie,
- name, n_inode);
- mutex_unlock(&ih->mutex);
- }
- }
- mutex_unlock(&inode->inotify_mutex);
-}
-EXPORT_SYMBOL_GPL(inotify_inode_queue_event);
-
-/**
- * inotify_dentry_parent_queue_event - queue an event to a dentry's parent
- * @dentry: the dentry in question, we queue against this dentry's parent
- * @mask: event mask describing this event
- * @cookie: cookie for synchronization, or zero
- * @name: filename, if any
- */
-void inotify_dentry_parent_queue_event(struct dentry *dentry, u32 mask,
- u32 cookie, const char *name)
-{
- struct dentry *parent;
- struct inode *inode;
-
- if (!(dentry->d_flags & DCACHE_INOTIFY_PARENT_WATCHED))
- return;
-
- spin_lock(&dentry->d_lock);
- parent = dentry->d_parent;
- inode = parent->d_inode;
-
- if (inotify_inode_watched(inode)) {
- dget(parent);
- spin_unlock(&dentry->d_lock);
- inotify_inode_queue_event(inode, mask, cookie, name,
- dentry->d_inode);
- dput(parent);
- } else
- spin_unlock(&dentry->d_lock);
-}
-EXPORT_SYMBOL_GPL(inotify_dentry_parent_queue_event);
-
-/**
- * inotify_get_cookie - return a unique cookie for use in synchronizing events.
- */
-u32 inotify_get_cookie(void)
-{
- return atomic_inc_return(&inotify_cookie);
-}
-EXPORT_SYMBOL_GPL(inotify_get_cookie);
-
-/**
- * inotify_unmount_inodes - an sb is unmounting. handle any watched inodes.
- * @list: list of inodes being unmounted (sb->s_inodes)
- *
- * Called with inode_lock held, protecting the unmounting super block's list
- * of inodes, and with iprune_mutex held, keeping shrink_icache_memory() at bay.
- * We temporarily drop inode_lock, however, and CAN block.
- */
-void inotify_unmount_inodes(struct list_head *list)
-{
- struct inode *inode, *next_i, *need_iput = NULL;
-
- list_for_each_entry_safe(inode, next_i, list, i_sb_list) {
- struct inotify_watch *watch, *next_w;
- struct inode *need_iput_tmp;
- struct list_head *watches;
-
- /*
- * We cannot __iget() an inode in state I_CLEAR, I_FREEING,
- * I_WILL_FREE, or I_NEW which is fine because by that point
- * the inode cannot have any associated watches.
- */
- if (inode->i_state & (I_CLEAR|I_FREEING|I_WILL_FREE|I_NEW))
- continue;
-
- /*
- * If i_count is zero, the inode cannot have any watches and
- * doing an __iget/iput with MS_ACTIVE clear would actually
- * evict all inodes with zero i_count from icache which is
- * unnecessarily violent and may in fact be illegal to do.
- */
- if (!atomic_read(&inode->i_count))
- continue;
-
- need_iput_tmp = need_iput;
- need_iput = NULL;
- /* In case inotify_remove_watch_locked() drops a reference. */
- if (inode != need_iput_tmp)
- __iget(inode);
- else
- need_iput_tmp = NULL;
- /* In case the dropping of a reference would nuke next_i. */
- if ((&next_i->i_sb_list != list) &&
- atomic_read(&next_i->i_count) &&
- !(next_i->i_state & (I_CLEAR | I_FREEING |
- I_WILL_FREE))) {
- __iget(next_i);
- need_iput = next_i;
- }
-
- /*
- * We can safely drop inode_lock here because we hold
- * references on both inode and next_i. Also no new inodes
- * will be added since the umount has begun. Finally,
- * iprune_mutex keeps shrink_icache_memory() away.
- */
- spin_unlock(&inode_lock);
-
- if (need_iput_tmp)
- iput(need_iput_tmp);
-
- /* for each watch, send IN_UNMOUNT and then remove it */
- mutex_lock(&inode->inotify_mutex);
- watches = &inode->inotify_watches;
- list_for_each_entry_safe(watch, next_w, watches, i_list) {
- struct inotify_handle *ih= watch->ih;
- get_inotify_watch(watch);
- mutex_lock(&ih->mutex);
- ih->in_ops->handle_event(watch, watch->wd, IN_UNMOUNT, 0,
- NULL, NULL);
- inotify_remove_watch_locked(ih, watch);
- mutex_unlock(&ih->mutex);
- put_inotify_watch(watch);
- }
- mutex_unlock(&inode->inotify_mutex);
- iput(inode);
-
- spin_lock(&inode_lock);
- }
-}
-EXPORT_SYMBOL_GPL(inotify_unmount_inodes);
-
-/**
- * inotify_inode_is_dead - an inode has been deleted, cleanup any watches
- * @inode: inode that is about to be removed
- */
-void inotify_inode_is_dead(struct inode *inode)
-{
- struct inotify_watch *watch, *next;
-
- mutex_lock(&inode->inotify_mutex);
- list_for_each_entry_safe(watch, next, &inode->inotify_watches, i_list) {
- struct inotify_handle *ih = watch->ih;
- mutex_lock(&ih->mutex);
- inotify_remove_watch_locked(ih, watch);
- mutex_unlock(&ih->mutex);
- }
- mutex_unlock(&inode->inotify_mutex);
-}
-EXPORT_SYMBOL_GPL(inotify_inode_is_dead);
-
-/* Kernel Consumer API */
-
-/**
- * inotify_init - allocate and initialize an inotify instance
- * @ops: caller's inotify operations
- */
-struct inotify_handle *inotify_init(const struct inotify_operations *ops)
-{
- struct inotify_handle *ih;
-
- ih = kmalloc(sizeof(struct inotify_handle), GFP_KERNEL);
- if (unlikely(!ih))
- return ERR_PTR(-ENOMEM);
-
- idr_init(&ih->idr);
- INIT_LIST_HEAD(&ih->watches);
- mutex_init(&ih->mutex);
- ih->last_wd = 0;
- ih->in_ops = ops;
- atomic_set(&ih->count, 0);
- get_inotify_handle(ih);
-
- return ih;
-}
-EXPORT_SYMBOL_GPL(inotify_init);
-
-/**
- * inotify_init_watch - initialize an inotify watch
- * @watch: watch to initialize
- */
-void inotify_init_watch(struct inotify_watch *watch)
-{
- INIT_LIST_HEAD(&watch->h_list);
- INIT_LIST_HEAD(&watch->i_list);
- atomic_set(&watch->count, 0);
- get_inotify_watch(watch); /* initial get */
-}
-EXPORT_SYMBOL_GPL(inotify_init_watch);
-
-/*
- * Watch removals suck violently. To kick the watch out we need (in this
- * order) inode->inotify_mutex and ih->mutex. That's fine if we have
- * a hold on inode; however, for all other cases we need to make damn sure
- * we don't race with umount. We can *NOT* just grab a reference to a
- * watch - inotify_unmount_inodes() will happily sail past it and we'll end
- * with reference to inode potentially outliving its superblock. Ideally
- * we just want to grab an active reference to superblock if we can; that
- * will make sure we won't go into inotify_umount_inodes() until we are
- * done. Cleanup is just deactivate_super(). However, that leaves a messy
- * case - what if we *are* racing with umount() and active references to
- * superblock can't be acquired anymore? We can bump ->s_count, grab
- * ->s_umount, which will wait until the superblock is shut down and the
- * watch in question is pining for fjords.
- *
- * And yes, this is far beyond mere "not very pretty"; so's the entire
- * concept of inotify to start with.
- */
-
-/**
- * pin_to_kill - pin the watch down for removal
- * @ih: inotify handle
- * @watch: watch to kill
- *
- * Called with ih->mutex held, drops it. Possible return values:
- * 0 - nothing to do, it has died
- * 1 - remove it, drop the reference and deactivate_super()
- */
-static int pin_to_kill(struct inotify_handle *ih, struct inotify_watch *watch)
-{
- struct super_block *sb = watch->inode->i_sb;
-
- if (atomic_inc_not_zero(&sb->s_active)) {
- get_inotify_watch(watch);
- mutex_unlock(&ih->mutex);
- return 1; /* the best outcome */
- }
- spin_lock(&sb_lock);
- sb->s_count++;
- spin_unlock(&sb_lock);
- mutex_unlock(&ih->mutex); /* can't grab ->s_umount under it */
- down_read(&sb->s_umount);
- /* fs is already shut down; the watch is dead */
- drop_super(sb);
- return 0;
-}
-
-static void unpin_and_kill(struct inotify_watch *watch)
-{
- struct super_block *sb = watch->inode->i_sb;
- put_inotify_watch(watch);
- deactivate_super(sb);
-}
-
-/**
- * inotify_destroy - clean up and destroy an inotify instance
- * @ih: inotify handle
- */
-void inotify_destroy(struct inotify_handle *ih)
-{
- /*
- * Destroy all of the watches for this handle. Unfortunately, not very
- * pretty. We cannot do a simple iteration over the list, because we
- * do not know the inode until we iterate to the watch. But we need to
- * hold inode->inotify_mutex before ih->mutex. The following works.
- *
- * AV: it had to become even uglier to start working ;-/
- */
- while (1) {
- struct inotify_watch *watch;
- struct list_head *watches;
- struct super_block *sb;
- struct inode *inode;
-
- mutex_lock(&ih->mutex);
- watches = &ih->watches;
- if (list_empty(watches)) {
- mutex_unlock(&ih->mutex);
- break;
- }
- watch = list_first_entry(watches, struct inotify_watch, h_list);
- sb = watch->inode->i_sb;
- if (!pin_to_kill(ih, watch))
- continue;
-
- inode = watch->inode;
- mutex_lock(&inode->inotify_mutex);
- mutex_lock(&ih->mutex);
-
- /* make sure we didn't race with another list removal */
- if (likely(idr_find(&ih->idr, watch->wd))) {
- remove_watch_no_event(watch, ih);
- put_inotify_watch(watch);
- }
-
- mutex_unlock(&ih->mutex);
- mutex_unlock(&inode->inotify_mutex);
- unpin_and_kill(watch);
- }
-
- /* free this handle: the put matching the get in inotify_init() */
- put_inotify_handle(ih);
-}
-EXPORT_SYMBOL_GPL(inotify_destroy);
-
-/**
- * inotify_find_watch - find an existing watch for an (ih,inode) pair
- * @ih: inotify handle
- * @inode: inode to watch
- * @watchp: pointer to existing inotify_watch
- *
- * Caller must pin given inode (via nameidata).
- */
-s32 inotify_find_watch(struct inotify_handle *ih, struct inode *inode,
- struct inotify_watch **watchp)
-{
- struct inotify_watch *old;
- int ret = -ENOENT;
-
- mutex_lock(&inode->inotify_mutex);
- mutex_lock(&ih->mutex);
-
- old = inode_find_handle(inode, ih);
- if (unlikely(old)) {
- get_inotify_watch(old); /* caller must put watch */
- *watchp = old;
- ret = old->wd;
- }
-
- mutex_unlock(&ih->mutex);
- mutex_unlock(&inode->inotify_mutex);
-
- return ret;
-}
-EXPORT_SYMBOL_GPL(inotify_find_watch);
-
-/**
- * inotify_find_update_watch - find and update the mask of an existing watch
- * @ih: inotify handle
- * @inode: inode's watch to update
- * @mask: mask of events to watch
- *
- * Caller must pin given inode (via nameidata).
- */
-s32 inotify_find_update_watch(struct inotify_handle *ih, struct inode *inode,
- u32 mask)
-{
- struct inotify_watch *old;
- int mask_add = 0;
- int ret;
-
- if (mask & IN_MASK_ADD)
- mask_add = 1;
-
- /* don't allow invalid bits: we don't want flags set */
- mask &= IN_ALL_EVENTS | IN_ONESHOT;
- if (unlikely(!mask))
- return -EINVAL;
-
- mutex_lock(&inode->inotify_mutex);
- mutex_lock(&ih->mutex);
-
- /*
- * Handle the case of re-adding a watch on an (inode,ih) pair that we
- * are already watching. We just update the mask and return its wd.
- */
- old = inode_find_handle(inode, ih);
- if (unlikely(!old)) {
- ret = -ENOENT;
- goto out;
- }
-
- if (mask_add)
- old->mask |= mask;
- else
- old->mask = mask;
- ret = old->wd;
-out:
- mutex_unlock(&ih->mutex);
- mutex_unlock(&inode->inotify_mutex);
- return ret;
-}
-EXPORT_SYMBOL_GPL(inotify_find_update_watch);
-
-/**
- * inotify_add_watch - add a watch to an inotify instance
- * @ih: inotify handle
- * @watch: caller allocated watch structure
- * @inode: inode to watch
- * @mask: mask of events to watch
- *
- * Caller must pin given inode (via nameidata).
- * Caller must ensure it only calls inotify_add_watch() once per watch.
- * Calls inotify_handle_get_wd() so may sleep.
- */
-s32 inotify_add_watch(struct inotify_handle *ih, struct inotify_watch *watch,
- struct inode *inode, u32 mask)
-{
- int ret = 0;
- int newly_watched;
-
- /* don't allow invalid bits: we don't want flags set */
- mask &= IN_ALL_EVENTS | IN_ONESHOT;
- if (unlikely(!mask))
- return -EINVAL;
- watch->mask = mask;
-
- mutex_lock(&inode->inotify_mutex);
- mutex_lock(&ih->mutex);
-
- /* Initialize a new watch */
- ret = inotify_handle_get_wd(ih, watch);
- if (unlikely(ret))
- goto out;
- ret = watch->wd;
-
- /* save a reference to handle and bump the count to make it official */
- get_inotify_handle(ih);
- watch->ih = ih;
-
- /*
- * Save a reference to the inode and bump the ref count to make it
- * official. We hold a reference to nameidata, which makes this safe.
- */
- watch->inode = igrab(inode);
-
- /* Add the watch to the handle's and the inode's list */
- newly_watched = !inotify_inode_watched(inode);
- list_add(&watch->h_list, &ih->watches);
- list_add(&watch->i_list, &inode->inotify_watches);
- /*
- * Set child flags _after_ adding the watch, so there is no race
- * windows where newly instantiated children could miss their parent's
- * watched flag.
- */
- if (newly_watched)
- set_dentry_child_flags(inode, 1);
-
-out:
- mutex_unlock(&ih->mutex);
- mutex_unlock(&inode->inotify_mutex);
- return ret;
-}
-EXPORT_SYMBOL_GPL(inotify_add_watch);
-
-/**
- * inotify_clone_watch - put the watch next to existing one
- * @old: already installed watch
- * @new: new watch
- *
- * Caller must hold the inotify_mutex of inode we are dealing with;
- * it is expected to remove the old watch before unlocking the inode.
- */
-s32 inotify_clone_watch(struct inotify_watch *old, struct inotify_watch *new)
-{
- struct inotify_handle *ih = old->ih;
- int ret = 0;
-
- new->mask = old->mask;
- new->ih = ih;
-
- mutex_lock(&ih->mutex);
-
- /* Initialize a new watch */
- ret = inotify_handle_get_wd(ih, new);
- if (unlikely(ret))
- goto out;
- ret = new->wd;
-
- get_inotify_handle(ih);
-
- new->inode = igrab(old->inode);
-
- list_add(&new->h_list, &ih->watches);
- list_add(&new->i_list, &old->inode->inotify_watches);
-out:
- mutex_unlock(&ih->mutex);
- return ret;
-}
-
-void inotify_evict_watch(struct inotify_watch *watch)
-{
- get_inotify_watch(watch);
- mutex_lock(&watch->ih->mutex);
- inotify_remove_watch_locked(watch->ih, watch);
- mutex_unlock(&watch->ih->mutex);
-}
-
-/**
- * inotify_rm_wd - remove a watch from an inotify instance
- * @ih: inotify handle
- * @wd: watch descriptor to remove
- *
- * Can sleep.
- */
-int inotify_rm_wd(struct inotify_handle *ih, u32 wd)
-{
- struct inotify_watch *watch;
- struct super_block *sb;
- struct inode *inode;
-
- mutex_lock(&ih->mutex);
- watch = idr_find(&ih->idr, wd);
- if (unlikely(!watch)) {
- mutex_unlock(&ih->mutex);
- return -EINVAL;
- }
- sb = watch->inode->i_sb;
- if (!pin_to_kill(ih, watch))
- return 0;
-
- inode = watch->inode;
-
- mutex_lock(&inode->inotify_mutex);
- mutex_lock(&ih->mutex);
-
- /* make sure that we did not race */
- if (likely(idr_find(&ih->idr, wd) == watch))
- inotify_remove_watch_locked(ih, watch);
-
- mutex_unlock(&ih->mutex);
- mutex_unlock(&inode->inotify_mutex);
- unpin_and_kill(watch);
-
- return 0;
-}
-EXPORT_SYMBOL_GPL(inotify_rm_wd);
-
-/**
- * inotify_rm_watch - remove a watch from an inotify instance
- * @ih: inotify handle
- * @watch: watch to remove
- *
- * Can sleep.
- */
-int inotify_rm_watch(struct inotify_handle *ih,
- struct inotify_watch *watch)
-{
- return inotify_rm_wd(ih, watch->wd);
-}
-EXPORT_SYMBOL_GPL(inotify_rm_watch);
-
-/*
- * inotify_setup - core initialization function
- */
-static int __init inotify_setup(void)
-{
- BUILD_BUG_ON(IN_ACCESS != FS_ACCESS);
- BUILD_BUG_ON(IN_MODIFY != FS_MODIFY);
- BUILD_BUG_ON(IN_ATTRIB != FS_ATTRIB);
- BUILD_BUG_ON(IN_CLOSE_WRITE != FS_CLOSE_WRITE);
- BUILD_BUG_ON(IN_CLOSE_NOWRITE != FS_CLOSE_NOWRITE);
- BUILD_BUG_ON(IN_OPEN != FS_OPEN);
- BUILD_BUG_ON(IN_MOVED_FROM != FS_MOVED_FROM);
- BUILD_BUG_ON(IN_MOVED_TO != FS_MOVED_TO);
- BUILD_BUG_ON(IN_CREATE != FS_CREATE);
- BUILD_BUG_ON(IN_DELETE != FS_DELETE);
- BUILD_BUG_ON(IN_DELETE_SELF != FS_DELETE_SELF);
- BUILD_BUG_ON(IN_MOVE_SELF != FS_MOVE_SELF);
- BUILD_BUG_ON(IN_Q_OVERFLOW != FS_Q_OVERFLOW);
-
- BUILD_BUG_ON(IN_UNMOUNT != FS_UNMOUNT);
- BUILD_BUG_ON(IN_ISDIR != FS_IN_ISDIR);
- BUILD_BUG_ON(IN_IGNORED != FS_IN_IGNORED);
- BUILD_BUG_ON(IN_ONESHOT != FS_IN_ONESHOT);
-
- atomic_set(&inotify_cookie, 0);
-
- return 0;
-}
-
-module_init(inotify_setup);
* (C) Copyright 2005 Robert Love
*/
-#include <linux/dnotify.h>
-#include <linux/inotify.h>
#include <linux/fsnotify_backend.h>
#include <linux/audit.h>
#include <linux/slab.h>
struct inode *inode)
{
__fsnotify_d_instantiate(entry, inode);
-
- inotify_d_instantiate(entry, inode);
}
/* Notify this dentry's parent about a child's events. */
static inline void fsnotify_parent(struct dentry *dentry, __u32 mask)
{
__fsnotify_parent(dentry, mask);
-
- inotify_dentry_parent_queue_event(dentry, mask, 0, dentry->d_name.name);
}
/*
* cares about events from this entry.
*/
__fsnotify_update_dcache_flags(entry);
-
- inotify_d_move(entry);
}
/*
*/
static inline void fsnotify_link_count(struct inode *inode)
{
- inotify_inode_queue_event(inode, IN_ATTRIB, 0, NULL, NULL);
-
fsnotify(inode, FS_ATTRIB, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
}
int isdir, struct inode *target, struct dentry *moved)
{
struct inode *source = moved->d_inode;
- u32 in_cookie = inotify_get_cookie();
u32 fs_cookie = fsnotify_get_cookie();
__u32 old_dir_mask = (FS_EVENT_ON_CHILD | FS_MOVED_FROM);
__u32 new_dir_mask = (FS_EVENT_ON_CHILD | FS_MOVED_TO);
old_dir_mask |= FS_DN_RENAME;
if (isdir) {
- isdir = IN_ISDIR;
old_dir_mask |= FS_IN_ISDIR;
new_dir_mask |= FS_IN_ISDIR;
}
- inotify_inode_queue_event(old_dir, IN_MOVED_FROM|isdir, in_cookie, old_name,
- source);
- inotify_inode_queue_event(new_dir, IN_MOVED_TO|isdir, in_cookie, new_name,
- source);
-
fsnotify(old_dir, old_dir_mask, old_dir, FSNOTIFY_EVENT_INODE, old_name, fs_cookie);
fsnotify(new_dir, new_dir_mask, new_dir, FSNOTIFY_EVENT_INODE, new_name, fs_cookie);
- if (target) {
- inotify_inode_queue_event(target, IN_DELETE_SELF, 0, NULL, NULL);
- inotify_inode_is_dead(target);
-
- /* this is really a link_count change not a removal */
+ if (target)
fsnotify_link_count(target);
- }
- if (source) {
- inotify_inode_queue_event(source, IN_MOVE_SELF, 0, NULL, NULL);
+ if (source)
fsnotify(source, FS_MOVE_SELF, moved->d_inode, FSNOTIFY_EVENT_INODE, NULL, 0);
- }
audit_inode_child(moved, new_dir);
}
*/
static inline void fsnotify_inoderemove(struct inode *inode)
{
- inotify_inode_queue_event(inode, IN_DELETE_SELF, 0, NULL, NULL);
- inotify_inode_is_dead(inode);
-
fsnotify(inode, FS_DELETE_SELF, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
__fsnotify_inode_delete(inode);
}
*/
static inline void fsnotify_create(struct inode *inode, struct dentry *dentry)
{
- inotify_inode_queue_event(inode, IN_CREATE, 0, dentry->d_name.name,
- dentry->d_inode);
audit_inode_child(dentry, inode);
fsnotify(inode, FS_CREATE, dentry->d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0);
*/
static inline void fsnotify_link(struct inode *dir, struct inode *inode, struct dentry *new_dentry)
{
- inotify_inode_queue_event(dir, IN_CREATE, 0, new_dentry->d_name.name,
- inode);
fsnotify_link_count(inode);
audit_inode_child(new_dentry, dir);
__u32 mask = (FS_CREATE | FS_IN_ISDIR);
struct inode *d_inode = dentry->d_inode;
- inotify_inode_queue_event(inode, mask, 0, dentry->d_name.name, d_inode);
audit_inode_child(dentry, inode);
fsnotify(inode, mask, d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0);
if (S_ISDIR(inode->i_mode))
mask |= FS_IN_ISDIR;
- inotify_inode_queue_event(inode, mask, 0, NULL, NULL);
-
fsnotify_parent(dentry, mask);
fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
}
if (S_ISDIR(inode->i_mode))
mask |= FS_IN_ISDIR;
- inotify_inode_queue_event(inode, mask, 0, NULL, NULL);
-
fsnotify_parent(dentry, mask);
fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
}
if (S_ISDIR(inode->i_mode))
mask |= FS_IN_ISDIR;
- inotify_inode_queue_event(inode, mask, 0, NULL, NULL);
-
fsnotify_parent(dentry, mask);
fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
}
if (S_ISDIR(inode->i_mode))
mask |= FS_IN_ISDIR;
- inotify_inode_queue_event(inode, mask, 0, NULL, NULL);
-
fsnotify_parent(dentry, mask);
fsnotify(inode, mask, file, FSNOTIFY_EVENT_FILE, NULL, 0);
}
if (S_ISDIR(inode->i_mode))
mask |= FS_IN_ISDIR;
- inotify_inode_queue_event(inode, mask, 0, NULL, NULL);
-
fsnotify_parent(dentry, mask);
fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
}
if (mask) {
if (S_ISDIR(inode->i_mode))
mask |= FS_IN_ISDIR;
- inotify_inode_queue_event(inode, mask, 0, NULL, NULL);
-
fsnotify_parent(dentry, mask);
fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
}
}
-#if defined(CONFIG_INOTIFY) || defined(CONFIG_FSNOTIFY) /* notify helpers */
+#if defined(CONFIG_FSNOTIFY) /* notify helpers */
/*
* fsnotify_oldname_init - save off the old filename before we change it
#define IN_CLOEXEC O_CLOEXEC
#define IN_NONBLOCK O_NONBLOCK
-#ifdef __KERNEL__
-
-#include <linux/dcache.h>
-#include <linux/fs.h>
-
-/*
- * struct inotify_watch - represents a watch request on a specific inode
- *
- * h_list is protected by ih->mutex of the associated inotify_handle.
- * i_list, mask are protected by inode->inotify_mutex of the associated inode.
- * ih, inode, and wd are never written to once the watch is created.
- *
- * Callers must use the established inotify interfaces to access inotify_watch
- * contents. The content of this structure is private to the inotify
- * implementation.
- */
-struct inotify_watch {
- struct list_head h_list; /* entry in inotify_handle's list */
- struct list_head i_list; /* entry in inode's list */
- atomic_t count; /* reference count */
- struct inotify_handle *ih; /* associated inotify handle */
- struct inode *inode; /* associated inode */
- __s32 wd; /* watch descriptor */
- __u32 mask; /* event mask for this watch */
-};
-
-struct inotify_operations {
- void (*handle_event)(struct inotify_watch *, u32, u32, u32,
- const char *, struct inode *);
- void (*destroy_watch)(struct inotify_watch *);
-};
-
-#ifdef CONFIG_INOTIFY
-
-/* Kernel API for producing events */
-
-extern void inotify_d_instantiate(struct dentry *, struct inode *);
-extern void inotify_d_move(struct dentry *);
-extern void inotify_inode_queue_event(struct inode *, __u32, __u32,
- const char *, struct inode *);
-extern void inotify_dentry_parent_queue_event(struct dentry *, __u32, __u32,
- const char *);
-extern void inotify_unmount_inodes(struct list_head *);
-extern void inotify_inode_is_dead(struct inode *);
-extern u32 inotify_get_cookie(void);
-
-/* Kernel Consumer API */
-
-extern struct inotify_handle *inotify_init(const struct inotify_operations *);
-extern void inotify_init_watch(struct inotify_watch *);
-extern void inotify_destroy(struct inotify_handle *);
-extern __s32 inotify_find_watch(struct inotify_handle *, struct inode *,
- struct inotify_watch **);
-extern __s32 inotify_find_update_watch(struct inotify_handle *, struct inode *,
- u32);
-extern __s32 inotify_add_watch(struct inotify_handle *, struct inotify_watch *,
- struct inode *, __u32);
-extern __s32 inotify_clone_watch(struct inotify_watch *, struct inotify_watch *);
-extern void inotify_evict_watch(struct inotify_watch *);
-extern int inotify_rm_watch(struct inotify_handle *, struct inotify_watch *);
-extern int inotify_rm_wd(struct inotify_handle *, __u32);
-extern void inotify_remove_watch_locked(struct inotify_handle *,
- struct inotify_watch *);
-extern void get_inotify_watch(struct inotify_watch *);
-extern void put_inotify_watch(struct inotify_watch *);
-extern int pin_inotify_watch(struct inotify_watch *);
-extern void unpin_inotify_watch(struct inotify_watch *);
-
-#else
-
-static inline void inotify_d_instantiate(struct dentry *dentry,
- struct inode *inode)
-{
-}
-
-static inline void inotify_d_move(struct dentry *dentry)
-{
-}
-
-static inline void inotify_inode_queue_event(struct inode *inode,
- __u32 mask, __u32 cookie,
- const char *filename,
- struct inode *n_inode)
-{
-}
-
-static inline void inotify_dentry_parent_queue_event(struct dentry *dentry,
- __u32 mask, __u32 cookie,
- const char *filename)
-{
-}
-
-static inline void inotify_unmount_inodes(struct list_head *list)
-{
-}
-
-static inline void inotify_inode_is_dead(struct inode *inode)
-{
-}
-
-static inline u32 inotify_get_cookie(void)
-{
- return 0;
-}
-
-static inline struct inotify_handle *inotify_init(const struct inotify_operations *ops)
-{
- return ERR_PTR(-EOPNOTSUPP);
-}
-
-static inline void inotify_init_watch(struct inotify_watch *watch)
-{
-}
-
-static inline void inotify_destroy(struct inotify_handle *ih)
-{
-}
-
-static inline __s32 inotify_find_watch(struct inotify_handle *ih, struct inode *inode,
- struct inotify_watch **watchp)
-{
- return -EOPNOTSUPP;
-}
-
-static inline __s32 inotify_find_update_watch(struct inotify_handle *ih,
- struct inode *inode, u32 mask)
-{
- return -EOPNOTSUPP;
-}
-
-static inline __s32 inotify_add_watch(struct inotify_handle *ih,
- struct inotify_watch *watch,
- struct inode *inode, __u32 mask)
-{
- return -EOPNOTSUPP;
-}
-
-static inline int inotify_rm_watch(struct inotify_handle *ih,
- struct inotify_watch *watch)
-{
- return -EOPNOTSUPP;
-}
-
-static inline int inotify_rm_wd(struct inotify_handle *ih, __u32 wd)
-{
- return -EOPNOTSUPP;
-}
-
-static inline void inotify_remove_watch_locked(struct inotify_handle *ih,
- struct inotify_watch *watch)
-{
-}
-
-static inline void get_inotify_watch(struct inotify_watch *watch)
-{
-}
-
-static inline void put_inotify_watch(struct inotify_watch *watch)
-{
-}
-
-extern inline int pin_inotify_watch(struct inotify_watch *watch)
-{
- return 0;
-}
-
-extern inline void unpin_inotify_watch(struct inotify_watch *watch)
-{
-}
-
-#endif /* CONFIG_INOTIFY */
-
-#endif /* __KERNEL __ */
-
#endif /* _LINUX_INOTIFY_H */
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