--- /dev/null
+/*
+ * direct.c - NILFS direct block pointer.
+ *
+ * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
+ *
+ * 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 of the License, 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Written by Koji Sato <koji@osrg.net>.
+ */
+
+#include <linux/errno.h>
+#include "nilfs.h"
+#include "page.h"
+#include "direct.h"
+#include "alloc.h"
+
+static inline __le64 *nilfs_direct_dptrs(const struct nilfs_direct *direct)
+{
+ return (__le64 *)
+ ((struct nilfs_direct_node *)direct->d_bmap.b_u.u_data + 1);
+}
+
+static inline __u64
+nilfs_direct_get_ptr(const struct nilfs_direct *direct, __u64 key)
+{
+ return nilfs_bmap_dptr_to_ptr(*(nilfs_direct_dptrs(direct) + key));
+}
+
+static inline void nilfs_direct_set_ptr(struct nilfs_direct *direct,
+ __u64 key, __u64 ptr)
+{
+ *(nilfs_direct_dptrs(direct) + key) = nilfs_bmap_ptr_to_dptr(ptr);
+}
+
+static int nilfs_direct_lookup(const struct nilfs_bmap *bmap,
+ __u64 key, int level, __u64 *ptrp)
+{
+ struct nilfs_direct *direct;
+ __u64 ptr;
+
+ direct = (struct nilfs_direct *)bmap;
+ if ((key > NILFS_DIRECT_KEY_MAX) ||
+ (level != 1) || /* XXX: use macro for level 1 */
+ ((ptr = nilfs_direct_get_ptr(direct, key)) ==
+ NILFS_BMAP_INVALID_PTR))
+ return -ENOENT;
+
+ if (ptrp != NULL)
+ *ptrp = ptr;
+ return 0;
+}
+
+static __u64
+nilfs_direct_find_target_v(const struct nilfs_direct *direct, __u64 key)
+{
+ __u64 ptr;
+
+ ptr = nilfs_bmap_find_target_seq(&direct->d_bmap, key);
+ if (ptr != NILFS_BMAP_INVALID_PTR)
+ /* sequential access */
+ return ptr;
+ else
+ /* block group */
+ return nilfs_bmap_find_target_in_group(&direct->d_bmap);
+}
+
+static void nilfs_direct_set_target_v(struct nilfs_direct *direct,
+ __u64 key, __u64 ptr)
+{
+ direct->d_bmap.b_last_allocated_key = key;
+ direct->d_bmap.b_last_allocated_ptr = ptr;
+}
+
+static int nilfs_direct_prepare_insert(struct nilfs_direct *direct,
+ __u64 key,
+ union nilfs_bmap_ptr_req *req,
+ struct nilfs_bmap_stats *stats)
+{
+ int ret;
+
+ if (direct->d_ops->dop_find_target != NULL)
+ req->bpr_ptr = (*direct->d_ops->dop_find_target)(direct, key);
+ ret = (*direct->d_bmap.b_pops->bpop_prepare_alloc_ptr)(&direct->d_bmap,
+ req);
+ if (ret < 0)
+ return ret;
+
+ stats->bs_nblocks = 1;
+ return 0;
+}
+
+static void nilfs_direct_commit_insert(struct nilfs_direct *direct,
+ union nilfs_bmap_ptr_req *req,
+ __u64 key, __u64 ptr)
+{
+ struct buffer_head *bh;
+
+ /* ptr must be a pointer to a buffer head. */
+ bh = (struct buffer_head *)((unsigned long)ptr);
+ set_buffer_nilfs_volatile(bh);
+
+ if (direct->d_bmap.b_pops->bpop_commit_alloc_ptr != NULL)
+ (*direct->d_bmap.b_pops->bpop_commit_alloc_ptr)(
+ &direct->d_bmap, req);
+ nilfs_direct_set_ptr(direct, key, req->bpr_ptr);
+
+ if (!nilfs_bmap_dirty(&direct->d_bmap))
+ nilfs_bmap_set_dirty(&direct->d_bmap);
+
+ if (direct->d_ops->dop_set_target != NULL)
+ (*direct->d_ops->dop_set_target)(direct, key, req->bpr_ptr);
+}
+
+static int nilfs_direct_insert(struct nilfs_bmap *bmap, __u64 key, __u64 ptr)
+{
+ struct nilfs_direct *direct;
+ union nilfs_bmap_ptr_req req;
+ struct nilfs_bmap_stats stats;
+ int ret;
+
+ direct = (struct nilfs_direct *)bmap;
+ if (key > NILFS_DIRECT_KEY_MAX)
+ return -ENOENT;
+ if (nilfs_direct_get_ptr(direct, key) != NILFS_BMAP_INVALID_PTR)
+ return -EEXIST;
+
+ ret = nilfs_direct_prepare_insert(direct, key, &req, &stats);
+ if (ret < 0)
+ return ret;
+ nilfs_direct_commit_insert(direct, &req, key, ptr);
+ nilfs_bmap_add_blocks(bmap, stats.bs_nblocks);
+
+ return 0;
+}
+
+static int nilfs_direct_prepare_delete(struct nilfs_direct *direct,
+ union nilfs_bmap_ptr_req *req,
+ __u64 key,
+ struct nilfs_bmap_stats *stats)
+{
+ int ret;
+
+ if (direct->d_bmap.b_pops->bpop_prepare_end_ptr != NULL) {
+ req->bpr_ptr = nilfs_direct_get_ptr(direct, key);
+ ret = (*direct->d_bmap.b_pops->bpop_prepare_end_ptr)(
+ &direct->d_bmap, req);
+ if (ret < 0)
+ return ret;
+ }
+
+ stats->bs_nblocks = 1;
+ return 0;
+}
+
+static void nilfs_direct_commit_delete(struct nilfs_direct *direct,
+ union nilfs_bmap_ptr_req *req,
+ __u64 key)
+{
+ if (direct->d_bmap.b_pops->bpop_commit_end_ptr != NULL)
+ (*direct->d_bmap.b_pops->bpop_commit_end_ptr)(
+ &direct->d_bmap, req);
+ nilfs_direct_set_ptr(direct, key, NILFS_BMAP_INVALID_PTR);
+}
+
+static int nilfs_direct_delete(struct nilfs_bmap *bmap, __u64 key)
+{
+ struct nilfs_direct *direct;
+ union nilfs_bmap_ptr_req req;
+ struct nilfs_bmap_stats stats;
+ int ret;
+
+ direct = (struct nilfs_direct *)bmap;
+ if ((key > NILFS_DIRECT_KEY_MAX) ||
+ nilfs_direct_get_ptr(direct, key) == NILFS_BMAP_INVALID_PTR)
+ return -ENOENT;
+
+ ret = nilfs_direct_prepare_delete(direct, &req, key, &stats);
+ if (ret < 0)
+ return ret;
+ nilfs_direct_commit_delete(direct, &req, key);
+ nilfs_bmap_sub_blocks(bmap, stats.bs_nblocks);
+
+ return 0;
+}
+
+static int nilfs_direct_last_key(const struct nilfs_bmap *bmap, __u64 *keyp)
+{
+ struct nilfs_direct *direct;
+ __u64 key, lastkey;
+
+ direct = (struct nilfs_direct *)bmap;
+ lastkey = NILFS_DIRECT_KEY_MAX + 1;
+ for (key = NILFS_DIRECT_KEY_MIN; key <= NILFS_DIRECT_KEY_MAX; key++)
+ if (nilfs_direct_get_ptr(direct, key) !=
+ NILFS_BMAP_INVALID_PTR)
+ lastkey = key;
+
+ if (lastkey == NILFS_DIRECT_KEY_MAX + 1)
+ return -ENOENT;
+
+ BUG_ON(keyp == NULL);
+ *keyp = lastkey;
+
+ return 0;
+}
+
+static int nilfs_direct_check_insert(const struct nilfs_bmap *bmap, __u64 key)
+{
+ return key > NILFS_DIRECT_KEY_MAX;
+}
+
+static int nilfs_direct_gather_data(struct nilfs_bmap *bmap,
+ __u64 *keys, __u64 *ptrs, int nitems)
+{
+ struct nilfs_direct *direct;
+ __u64 key;
+ __u64 ptr;
+ int n;
+
+ direct = (struct nilfs_direct *)bmap;
+ if (nitems > NILFS_DIRECT_NBLOCKS)
+ nitems = NILFS_DIRECT_NBLOCKS;
+ n = 0;
+ for (key = 0; key < nitems; key++) {
+ ptr = nilfs_direct_get_ptr(direct, key);
+ if (ptr != NILFS_BMAP_INVALID_PTR) {
+ keys[n] = key;
+ ptrs[n] = ptr;
+ n++;
+ }
+ }
+ return n;
+}
+
+int nilfs_direct_delete_and_convert(struct nilfs_bmap *bmap,
+ __u64 key, __u64 *keys, __u64 *ptrs,
+ int n, __u64 low, __u64 high)
+{
+ struct nilfs_direct *direct;
+ __le64 *dptrs;
+ int ret, i, j;
+
+ /* no need to allocate any resource for conversion */
+
+ /* delete */
+ ret = (*bmap->b_ops->bop_delete)(bmap, key);
+ if (ret < 0)
+ return ret;
+
+ /* free resources */
+ if (bmap->b_ops->bop_clear != NULL)
+ (*bmap->b_ops->bop_clear)(bmap);
+
+ /* convert */
+ direct = (struct nilfs_direct *)bmap;
+ dptrs = nilfs_direct_dptrs(direct);
+ for (i = 0, j = 0; i < NILFS_DIRECT_NBLOCKS; i++) {
+ if ((j < n) && (i == keys[j])) {
+ dptrs[i] = (i != key) ?
+ nilfs_bmap_ptr_to_dptr(ptrs[j]) :
+ NILFS_BMAP_INVALID_PTR;
+ j++;
+ } else
+ dptrs[i] = NILFS_BMAP_INVALID_PTR;
+ }
+
+ nilfs_direct_init(bmap, low, high);
+
+ return 0;
+}
+
+static int nilfs_direct_propagate_v(struct nilfs_direct *direct,
+ struct buffer_head *bh)
+{
+ union nilfs_bmap_ptr_req oldreq, newreq;
+ __u64 key;
+ __u64 ptr;
+ int ret;
+
+ key = nilfs_bmap_data_get_key(&direct->d_bmap, bh);
+ ptr = nilfs_direct_get_ptr(direct, key);
+ if (!buffer_nilfs_volatile(bh)) {
+ oldreq.bpr_ptr = ptr;
+ newreq.bpr_ptr = ptr;
+ ret = nilfs_bmap_prepare_update(&direct->d_bmap, &oldreq,
+ &newreq);
+ if (ret < 0)
+ return ret;
+ nilfs_bmap_commit_update(&direct->d_bmap, &oldreq, &newreq);
+ set_buffer_nilfs_volatile(bh);
+ nilfs_direct_set_ptr(direct, key, newreq.bpr_ptr);
+ } else
+ ret = nilfs_bmap_mark_dirty(&direct->d_bmap, ptr);
+
+ return ret;
+}
+
+static int nilfs_direct_propagate(const struct nilfs_bmap *bmap,
+ struct buffer_head *bh)
+{
+ struct nilfs_direct *direct;
+
+ direct = (struct nilfs_direct *)bmap;
+ return (direct->d_ops->dop_propagate != NULL) ?
+ (*direct->d_ops->dop_propagate)(direct, bh) :
+ 0;
+}
+
+static int nilfs_direct_assign_v(struct nilfs_direct *direct,
+ __u64 key, __u64 ptr,
+ struct buffer_head **bh,
+ sector_t blocknr,
+ union nilfs_binfo *binfo)
+{
+ union nilfs_bmap_ptr_req req;
+ int ret;
+
+ req.bpr_ptr = ptr;
+ ret = (*direct->d_bmap.b_pops->bpop_prepare_start_ptr)(
+ &direct->d_bmap, &req);
+ if (ret < 0)
+ return ret;
+ (*direct->d_bmap.b_pops->bpop_commit_start_ptr)(&direct->d_bmap,
+ &req, blocknr);
+
+ binfo->bi_v.bi_vblocknr = nilfs_bmap_ptr_to_dptr(ptr);
+ binfo->bi_v.bi_blkoff = nilfs_bmap_key_to_dkey(key);
+
+ return 0;
+}
+
+static int nilfs_direct_assign_p(struct nilfs_direct *direct,
+ __u64 key, __u64 ptr,
+ struct buffer_head **bh,
+ sector_t blocknr,
+ union nilfs_binfo *binfo)
+{
+ nilfs_direct_set_ptr(direct, key, blocknr);
+
+ binfo->bi_dat.bi_blkoff = nilfs_bmap_key_to_dkey(key);
+ binfo->bi_dat.bi_level = 0;
+
+ return 0;
+}
+
+static int nilfs_direct_assign(struct nilfs_bmap *bmap,
+ struct buffer_head **bh,
+ sector_t blocknr,
+ union nilfs_binfo *binfo)
+{
+ struct nilfs_direct *direct;
+ __u64 key;
+ __u64 ptr;
+
+ direct = (struct nilfs_direct *)bmap;
+ key = nilfs_bmap_data_get_key(bmap, *bh);
+ BUG_ON(key > NILFS_DIRECT_KEY_MAX);
+ ptr = nilfs_direct_get_ptr(direct, key);
+ BUG_ON(ptr == NILFS_BMAP_INVALID_PTR);
+
+ return (*direct->d_ops->dop_assign)(direct, key, ptr, bh,
+ blocknr, binfo);
+}
+
+static const struct nilfs_bmap_operations nilfs_direct_ops = {
+ .bop_lookup = nilfs_direct_lookup,
+ .bop_insert = nilfs_direct_insert,
+ .bop_delete = nilfs_direct_delete,
+ .bop_clear = NULL,
+
+ .bop_propagate = nilfs_direct_propagate,
+
+ .bop_lookup_dirty_buffers = NULL,
+
+ .bop_assign = nilfs_direct_assign,
+ .bop_mark = NULL,
+
+ .bop_last_key = nilfs_direct_last_key,
+ .bop_check_insert = nilfs_direct_check_insert,
+ .bop_check_delete = NULL,
+ .bop_gather_data = nilfs_direct_gather_data,
+};
+
+
+static const struct nilfs_direct_operations nilfs_direct_ops_v = {
+ .dop_find_target = nilfs_direct_find_target_v,
+ .dop_set_target = nilfs_direct_set_target_v,
+ .dop_propagate = nilfs_direct_propagate_v,
+ .dop_assign = nilfs_direct_assign_v,
+};
+
+static const struct nilfs_direct_operations nilfs_direct_ops_p = {
+ .dop_find_target = NULL,
+ .dop_set_target = NULL,
+ .dop_propagate = NULL,
+ .dop_assign = nilfs_direct_assign_p,
+};
+
+int nilfs_direct_init(struct nilfs_bmap *bmap, __u64 low, __u64 high)
+{
+ struct nilfs_direct *direct;
+
+ direct = (struct nilfs_direct *)bmap;
+ bmap->b_ops = &nilfs_direct_ops;
+ bmap->b_low = low;
+ bmap->b_high = high;
+ switch (bmap->b_inode->i_ino) {
+ case NILFS_DAT_INO:
+ direct->d_ops = &nilfs_direct_ops_p;
+ break;
+ default:
+ direct->d_ops = &nilfs_direct_ops_v;
+ break;
+ }
+
+ return 0;
+}
--- /dev/null
+/*
+ * direct.h - NILFS direct block pointer.
+ *
+ * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
+ *
+ * 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 of the License, 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Written by Koji Sato <koji@osrg.net>.
+ */
+
+#ifndef _NILFS_DIRECT_H
+#define _NILFS_DIRECT_H
+
+#include <linux/types.h>
+#include <linux/buffer_head.h>
+#include "bmap.h"
+
+
+struct nilfs_direct;
+
+/**
+ * struct nilfs_direct_operations - direct mapping operation table
+ */
+struct nilfs_direct_operations {
+ __u64 (*dop_find_target)(const struct nilfs_direct *, __u64);
+ void (*dop_set_target)(struct nilfs_direct *, __u64, __u64);
+ int (*dop_propagate)(struct nilfs_direct *, struct buffer_head *);
+ int (*dop_assign)(struct nilfs_direct *, __u64, __u64,
+ struct buffer_head **, sector_t,
+ union nilfs_binfo *);
+};
+
+/**
+ * struct nilfs_direct_node - direct node
+ * @dn_flags: flags
+ * @dn_pad: padding
+ */
+struct nilfs_direct_node {
+ __u8 dn_flags;
+ __u8 pad[7];
+};
+
+/**
+ * struct nilfs_direct - direct mapping
+ * @d_bmap: bmap structure
+ * @d_ops: direct mapping operation table
+ */
+struct nilfs_direct {
+ struct nilfs_bmap d_bmap;
+
+ /* direct-mapping-specific members */
+ const struct nilfs_direct_operations *d_ops;
+};
+
+
+#define NILFS_DIRECT_NBLOCKS (NILFS_BMAP_SIZE / sizeof(__le64) - 1)
+#define NILFS_DIRECT_KEY_MIN 0
+#define NILFS_DIRECT_KEY_MAX (NILFS_DIRECT_NBLOCKS - 1)
+
+
+int nilfs_direct_init(struct nilfs_bmap *, __u64, __u64);
+int nilfs_direct_delete_and_convert(struct nilfs_bmap *, __u64, __u64 *,
+ __u64 *, int, __u64, __u64);
+
+
+#endif /* _NILFS_DIRECT_H */
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