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-rw-r--r--kernel/fs/nilfs2/btree.c2414
1 files changed, 2414 insertions, 0 deletions
diff --git a/kernel/fs/nilfs2/btree.c b/kernel/fs/nilfs2/btree.c
new file mode 100644
index 000000000..919fd5bb1
--- /dev/null
+++ b/kernel/fs/nilfs2/btree.c
@@ -0,0 +1,2414 @@
+/*
+ * btree.c - NILFS B-tree.
+ *
+ * Copyright (C) 2005-2008 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/slab.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/pagevec.h>
+#include "nilfs.h"
+#include "page.h"
+#include "btnode.h"
+#include "btree.h"
+#include "alloc.h"
+#include "dat.h"
+
+static void __nilfs_btree_init(struct nilfs_bmap *bmap);
+
+static struct nilfs_btree_path *nilfs_btree_alloc_path(void)
+{
+ struct nilfs_btree_path *path;
+ int level = NILFS_BTREE_LEVEL_DATA;
+
+ path = kmem_cache_alloc(nilfs_btree_path_cache, GFP_NOFS);
+ if (path == NULL)
+ goto out;
+
+ for (; level < NILFS_BTREE_LEVEL_MAX; level++) {
+ path[level].bp_bh = NULL;
+ path[level].bp_sib_bh = NULL;
+ path[level].bp_index = 0;
+ path[level].bp_oldreq.bpr_ptr = NILFS_BMAP_INVALID_PTR;
+ path[level].bp_newreq.bpr_ptr = NILFS_BMAP_INVALID_PTR;
+ path[level].bp_op = NULL;
+ }
+
+out:
+ return path;
+}
+
+static void nilfs_btree_free_path(struct nilfs_btree_path *path)
+{
+ int level = NILFS_BTREE_LEVEL_DATA;
+
+ for (; level < NILFS_BTREE_LEVEL_MAX; level++)
+ brelse(path[level].bp_bh);
+
+ kmem_cache_free(nilfs_btree_path_cache, path);
+}
+
+/*
+ * B-tree node operations
+ */
+static int nilfs_btree_get_new_block(const struct nilfs_bmap *btree,
+ __u64 ptr, struct buffer_head **bhp)
+{
+ struct address_space *btnc = &NILFS_BMAP_I(btree)->i_btnode_cache;
+ struct buffer_head *bh;
+
+ bh = nilfs_btnode_create_block(btnc, ptr);
+ if (!bh)
+ return -ENOMEM;
+
+ set_buffer_nilfs_volatile(bh);
+ *bhp = bh;
+ return 0;
+}
+
+static int nilfs_btree_node_get_flags(const struct nilfs_btree_node *node)
+{
+ return node->bn_flags;
+}
+
+static void
+nilfs_btree_node_set_flags(struct nilfs_btree_node *node, int flags)
+{
+ node->bn_flags = flags;
+}
+
+static int nilfs_btree_node_root(const struct nilfs_btree_node *node)
+{
+ return nilfs_btree_node_get_flags(node) & NILFS_BTREE_NODE_ROOT;
+}
+
+static int nilfs_btree_node_get_level(const struct nilfs_btree_node *node)
+{
+ return node->bn_level;
+}
+
+static void
+nilfs_btree_node_set_level(struct nilfs_btree_node *node, int level)
+{
+ node->bn_level = level;
+}
+
+static int nilfs_btree_node_get_nchildren(const struct nilfs_btree_node *node)
+{
+ return le16_to_cpu(node->bn_nchildren);
+}
+
+static void
+nilfs_btree_node_set_nchildren(struct nilfs_btree_node *node, int nchildren)
+{
+ node->bn_nchildren = cpu_to_le16(nchildren);
+}
+
+static int nilfs_btree_node_size(const struct nilfs_bmap *btree)
+{
+ return 1 << btree->b_inode->i_blkbits;
+}
+
+static int nilfs_btree_nchildren_per_block(const struct nilfs_bmap *btree)
+{
+ return btree->b_nchildren_per_block;
+}
+
+static __le64 *
+nilfs_btree_node_dkeys(const struct nilfs_btree_node *node)
+{
+ return (__le64 *)((char *)(node + 1) +
+ (nilfs_btree_node_root(node) ?
+ 0 : NILFS_BTREE_NODE_EXTRA_PAD_SIZE));
+}
+
+static __le64 *
+nilfs_btree_node_dptrs(const struct nilfs_btree_node *node, int ncmax)
+{
+ return (__le64 *)(nilfs_btree_node_dkeys(node) + ncmax);
+}
+
+static __u64
+nilfs_btree_node_get_key(const struct nilfs_btree_node *node, int index)
+{
+ return le64_to_cpu(*(nilfs_btree_node_dkeys(node) + index));
+}
+
+static void
+nilfs_btree_node_set_key(struct nilfs_btree_node *node, int index, __u64 key)
+{
+ *(nilfs_btree_node_dkeys(node) + index) = cpu_to_le64(key);
+}
+
+static __u64
+nilfs_btree_node_get_ptr(const struct nilfs_btree_node *node, int index,
+ int ncmax)
+{
+ return le64_to_cpu(*(nilfs_btree_node_dptrs(node, ncmax) + index));
+}
+
+static void
+nilfs_btree_node_set_ptr(struct nilfs_btree_node *node, int index, __u64 ptr,
+ int ncmax)
+{
+ *(nilfs_btree_node_dptrs(node, ncmax) + index) = cpu_to_le64(ptr);
+}
+
+static void nilfs_btree_node_init(struct nilfs_btree_node *node, int flags,
+ int level, int nchildren, int ncmax,
+ const __u64 *keys, const __u64 *ptrs)
+{
+ __le64 *dkeys;
+ __le64 *dptrs;
+ int i;
+
+ nilfs_btree_node_set_flags(node, flags);
+ nilfs_btree_node_set_level(node, level);
+ nilfs_btree_node_set_nchildren(node, nchildren);
+
+ dkeys = nilfs_btree_node_dkeys(node);
+ dptrs = nilfs_btree_node_dptrs(node, ncmax);
+ for (i = 0; i < nchildren; i++) {
+ dkeys[i] = cpu_to_le64(keys[i]);
+ dptrs[i] = cpu_to_le64(ptrs[i]);
+ }
+}
+
+/* Assume the buffer heads corresponding to left and right are locked. */
+static void nilfs_btree_node_move_left(struct nilfs_btree_node *left,
+ struct nilfs_btree_node *right,
+ int n, int lncmax, int rncmax)
+{
+ __le64 *ldkeys, *rdkeys;
+ __le64 *ldptrs, *rdptrs;
+ int lnchildren, rnchildren;
+
+ ldkeys = nilfs_btree_node_dkeys(left);
+ ldptrs = nilfs_btree_node_dptrs(left, lncmax);
+ lnchildren = nilfs_btree_node_get_nchildren(left);
+
+ rdkeys = nilfs_btree_node_dkeys(right);
+ rdptrs = nilfs_btree_node_dptrs(right, rncmax);
+ rnchildren = nilfs_btree_node_get_nchildren(right);
+
+ memcpy(ldkeys + lnchildren, rdkeys, n * sizeof(*rdkeys));
+ memcpy(ldptrs + lnchildren, rdptrs, n * sizeof(*rdptrs));
+ memmove(rdkeys, rdkeys + n, (rnchildren - n) * sizeof(*rdkeys));
+ memmove(rdptrs, rdptrs + n, (rnchildren - n) * sizeof(*rdptrs));
+
+ lnchildren += n;
+ rnchildren -= n;
+ nilfs_btree_node_set_nchildren(left, lnchildren);
+ nilfs_btree_node_set_nchildren(right, rnchildren);
+}
+
+/* Assume that the buffer heads corresponding to left and right are locked. */
+static void nilfs_btree_node_move_right(struct nilfs_btree_node *left,
+ struct nilfs_btree_node *right,
+ int n, int lncmax, int rncmax)
+{
+ __le64 *ldkeys, *rdkeys;
+ __le64 *ldptrs, *rdptrs;
+ int lnchildren, rnchildren;
+
+ ldkeys = nilfs_btree_node_dkeys(left);
+ ldptrs = nilfs_btree_node_dptrs(left, lncmax);
+ lnchildren = nilfs_btree_node_get_nchildren(left);
+
+ rdkeys = nilfs_btree_node_dkeys(right);
+ rdptrs = nilfs_btree_node_dptrs(right, rncmax);
+ rnchildren = nilfs_btree_node_get_nchildren(right);
+
+ memmove(rdkeys + n, rdkeys, rnchildren * sizeof(*rdkeys));
+ memmove(rdptrs + n, rdptrs, rnchildren * sizeof(*rdptrs));
+ memcpy(rdkeys, ldkeys + lnchildren - n, n * sizeof(*rdkeys));
+ memcpy(rdptrs, ldptrs + lnchildren - n, n * sizeof(*rdptrs));
+
+ lnchildren -= n;
+ rnchildren += n;
+ nilfs_btree_node_set_nchildren(left, lnchildren);
+ nilfs_btree_node_set_nchildren(right, rnchildren);
+}
+
+/* Assume that the buffer head corresponding to node is locked. */
+static void nilfs_btree_node_insert(struct nilfs_btree_node *node, int index,
+ __u64 key, __u64 ptr, int ncmax)
+{
+ __le64 *dkeys;
+ __le64 *dptrs;
+ int nchildren;
+
+ dkeys = nilfs_btree_node_dkeys(node);
+ dptrs = nilfs_btree_node_dptrs(node, ncmax);
+ nchildren = nilfs_btree_node_get_nchildren(node);
+ if (index < nchildren) {
+ memmove(dkeys + index + 1, dkeys + index,
+ (nchildren - index) * sizeof(*dkeys));
+ memmove(dptrs + index + 1, dptrs + index,
+ (nchildren - index) * sizeof(*dptrs));
+ }
+ dkeys[index] = cpu_to_le64(key);
+ dptrs[index] = cpu_to_le64(ptr);
+ nchildren++;
+ nilfs_btree_node_set_nchildren(node, nchildren);
+}
+
+/* Assume that the buffer head corresponding to node is locked. */
+static void nilfs_btree_node_delete(struct nilfs_btree_node *node, int index,
+ __u64 *keyp, __u64 *ptrp, int ncmax)
+{
+ __u64 key;
+ __u64 ptr;
+ __le64 *dkeys;
+ __le64 *dptrs;
+ int nchildren;
+
+ dkeys = nilfs_btree_node_dkeys(node);
+ dptrs = nilfs_btree_node_dptrs(node, ncmax);
+ key = le64_to_cpu(dkeys[index]);
+ ptr = le64_to_cpu(dptrs[index]);
+ nchildren = nilfs_btree_node_get_nchildren(node);
+ if (keyp != NULL)
+ *keyp = key;
+ if (ptrp != NULL)
+ *ptrp = ptr;
+
+ if (index < nchildren - 1) {
+ memmove(dkeys + index, dkeys + index + 1,
+ (nchildren - index - 1) * sizeof(*dkeys));
+ memmove(dptrs + index, dptrs + index + 1,
+ (nchildren - index - 1) * sizeof(*dptrs));
+ }
+ nchildren--;
+ nilfs_btree_node_set_nchildren(node, nchildren);
+}
+
+static int nilfs_btree_node_lookup(const struct nilfs_btree_node *node,
+ __u64 key, int *indexp)
+{
+ __u64 nkey;
+ int index, low, high, s;
+
+ /* binary search */
+ low = 0;
+ high = nilfs_btree_node_get_nchildren(node) - 1;
+ index = 0;
+ s = 0;
+ while (low <= high) {
+ index = (low + high) / 2;
+ nkey = nilfs_btree_node_get_key(node, index);
+ if (nkey == key) {
+ s = 0;
+ goto out;
+ } else if (nkey < key) {
+ low = index + 1;
+ s = -1;
+ } else {
+ high = index - 1;
+ s = 1;
+ }
+ }
+
+ /* adjust index */
+ if (nilfs_btree_node_get_level(node) > NILFS_BTREE_LEVEL_NODE_MIN) {
+ if (s > 0 && index > 0)
+ index--;
+ } else if (s < 0)
+ index++;
+
+ out:
+ *indexp = index;
+
+ return s == 0;
+}
+
+/**
+ * nilfs_btree_node_broken - verify consistency of btree node
+ * @node: btree node block to be examined
+ * @size: node size (in bytes)
+ * @blocknr: block number
+ *
+ * Return Value: If node is broken, 1 is returned. Otherwise, 0 is returned.
+ */
+static int nilfs_btree_node_broken(const struct nilfs_btree_node *node,
+ size_t size, sector_t blocknr)
+{
+ int level, flags, nchildren;
+ int ret = 0;
+
+ level = nilfs_btree_node_get_level(node);
+ flags = nilfs_btree_node_get_flags(node);
+ nchildren = nilfs_btree_node_get_nchildren(node);
+
+ if (unlikely(level < NILFS_BTREE_LEVEL_NODE_MIN ||
+ level >= NILFS_BTREE_LEVEL_MAX ||
+ (flags & NILFS_BTREE_NODE_ROOT) ||
+ nchildren < 0 ||
+ nchildren > NILFS_BTREE_NODE_NCHILDREN_MAX(size))) {
+ printk(KERN_CRIT "NILFS: bad btree node (blocknr=%llu): "
+ "level = %d, flags = 0x%x, nchildren = %d\n",
+ (unsigned long long)blocknr, level, flags, nchildren);
+ ret = 1;
+ }
+ return ret;
+}
+
+/**
+ * nilfs_btree_root_broken - verify consistency of btree root node
+ * @node: btree root node to be examined
+ * @ino: inode number
+ *
+ * Return Value: If node is broken, 1 is returned. Otherwise, 0 is returned.
+ */
+static int nilfs_btree_root_broken(const struct nilfs_btree_node *node,
+ unsigned long ino)
+{
+ int level, flags, nchildren;
+ int ret = 0;
+
+ level = nilfs_btree_node_get_level(node);
+ flags = nilfs_btree_node_get_flags(node);
+ nchildren = nilfs_btree_node_get_nchildren(node);
+
+ if (unlikely(level < NILFS_BTREE_LEVEL_NODE_MIN ||
+ level >= NILFS_BTREE_LEVEL_MAX ||
+ nchildren < 0 ||
+ nchildren > NILFS_BTREE_ROOT_NCHILDREN_MAX)) {
+ pr_crit("NILFS: bad btree root (inode number=%lu): level = %d, flags = 0x%x, nchildren = %d\n",
+ ino, level, flags, nchildren);
+ ret = 1;
+ }
+ return ret;
+}
+
+int nilfs_btree_broken_node_block(struct buffer_head *bh)
+{
+ int ret;
+
+ if (buffer_nilfs_checked(bh))
+ return 0;
+
+ ret = nilfs_btree_node_broken((struct nilfs_btree_node *)bh->b_data,
+ bh->b_size, bh->b_blocknr);
+ if (likely(!ret))
+ set_buffer_nilfs_checked(bh);
+ return ret;
+}
+
+static struct nilfs_btree_node *
+nilfs_btree_get_root(const struct nilfs_bmap *btree)
+{
+ return (struct nilfs_btree_node *)btree->b_u.u_data;
+}
+
+static struct nilfs_btree_node *
+nilfs_btree_get_nonroot_node(const struct nilfs_btree_path *path, int level)
+{
+ return (struct nilfs_btree_node *)path[level].bp_bh->b_data;
+}
+
+static struct nilfs_btree_node *
+nilfs_btree_get_sib_node(const struct nilfs_btree_path *path, int level)
+{
+ return (struct nilfs_btree_node *)path[level].bp_sib_bh->b_data;
+}
+
+static int nilfs_btree_height(const struct nilfs_bmap *btree)
+{
+ return nilfs_btree_node_get_level(nilfs_btree_get_root(btree)) + 1;
+}
+
+static struct nilfs_btree_node *
+nilfs_btree_get_node(const struct nilfs_bmap *btree,
+ const struct nilfs_btree_path *path,
+ int level, int *ncmaxp)
+{
+ struct nilfs_btree_node *node;
+
+ if (level == nilfs_btree_height(btree) - 1) {
+ node = nilfs_btree_get_root(btree);
+ *ncmaxp = NILFS_BTREE_ROOT_NCHILDREN_MAX;
+ } else {
+ node = nilfs_btree_get_nonroot_node(path, level);
+ *ncmaxp = nilfs_btree_nchildren_per_block(btree);
+ }
+ return node;
+}
+
+static int
+nilfs_btree_bad_node(struct nilfs_btree_node *node, int level)
+{
+ if (unlikely(nilfs_btree_node_get_level(node) != level)) {
+ dump_stack();
+ printk(KERN_CRIT "NILFS: btree level mismatch: %d != %d\n",
+ nilfs_btree_node_get_level(node), level);
+ return 1;
+ }
+ return 0;
+}
+
+struct nilfs_btree_readahead_info {
+ struct nilfs_btree_node *node; /* parent node */
+ int max_ra_blocks; /* max nof blocks to read ahead */
+ int index; /* current index on the parent node */
+ int ncmax; /* nof children in the parent node */
+};
+
+static int __nilfs_btree_get_block(const struct nilfs_bmap *btree, __u64 ptr,
+ struct buffer_head **bhp,
+ const struct nilfs_btree_readahead_info *ra)
+{
+ struct address_space *btnc = &NILFS_BMAP_I(btree)->i_btnode_cache;
+ struct buffer_head *bh, *ra_bh;
+ sector_t submit_ptr = 0;
+ int ret;
+
+ ret = nilfs_btnode_submit_block(btnc, ptr, 0, READ, &bh, &submit_ptr);
+ if (ret) {
+ if (ret != -EEXIST)
+ return ret;
+ goto out_check;
+ }
+
+ if (ra) {
+ int i, n;
+ __u64 ptr2;
+
+ /* read ahead sibling nodes */
+ for (n = ra->max_ra_blocks, i = ra->index + 1;
+ n > 0 && i < ra->ncmax; n--, i++) {
+ ptr2 = nilfs_btree_node_get_ptr(ra->node, i, ra->ncmax);
+
+ ret = nilfs_btnode_submit_block(btnc, ptr2, 0, READA,
+ &ra_bh, &submit_ptr);
+ if (likely(!ret || ret == -EEXIST))
+ brelse(ra_bh);
+ else if (ret != -EBUSY)
+ break;
+ if (!buffer_locked(bh))
+ goto out_no_wait;
+ }
+ }
+
+ wait_on_buffer(bh);
+
+ out_no_wait:
+ if (!buffer_uptodate(bh)) {
+ brelse(bh);
+ return -EIO;
+ }
+
+ out_check:
+ if (nilfs_btree_broken_node_block(bh)) {
+ clear_buffer_uptodate(bh);
+ brelse(bh);
+ return -EINVAL;
+ }
+
+ *bhp = bh;
+ return 0;
+}
+
+static int nilfs_btree_get_block(const struct nilfs_bmap *btree, __u64 ptr,
+ struct buffer_head **bhp)
+{
+ return __nilfs_btree_get_block(btree, ptr, bhp, NULL);
+}
+
+static int nilfs_btree_do_lookup(const struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ __u64 key, __u64 *ptrp, int minlevel,
+ int readahead)
+{
+ struct nilfs_btree_node *node;
+ struct nilfs_btree_readahead_info p, *ra;
+ __u64 ptr;
+ int level, index, found, ncmax, ret;
+
+ node = nilfs_btree_get_root(btree);
+ level = nilfs_btree_node_get_level(node);
+ if (level < minlevel || nilfs_btree_node_get_nchildren(node) <= 0)
+ return -ENOENT;
+
+ found = nilfs_btree_node_lookup(node, key, &index);
+ ptr = nilfs_btree_node_get_ptr(node, index,
+ NILFS_BTREE_ROOT_NCHILDREN_MAX);
+ path[level].bp_bh = NULL;
+ path[level].bp_index = index;
+
+ ncmax = nilfs_btree_nchildren_per_block(btree);
+
+ while (--level >= minlevel) {
+ ra = NULL;
+ if (level == NILFS_BTREE_LEVEL_NODE_MIN && readahead) {
+ p.node = nilfs_btree_get_node(btree, path, level + 1,
+ &p.ncmax);
+ p.index = index;
+ p.max_ra_blocks = 7;
+ ra = &p;
+ }
+ ret = __nilfs_btree_get_block(btree, ptr, &path[level].bp_bh,
+ ra);
+ if (ret < 0)
+ return ret;
+
+ node = nilfs_btree_get_nonroot_node(path, level);
+ if (nilfs_btree_bad_node(node, level))
+ return -EINVAL;
+ if (!found)
+ found = nilfs_btree_node_lookup(node, key, &index);
+ else
+ index = 0;
+ if (index < ncmax) {
+ ptr = nilfs_btree_node_get_ptr(node, index, ncmax);
+ } else {
+ WARN_ON(found || level != NILFS_BTREE_LEVEL_NODE_MIN);
+ /* insert */
+ ptr = NILFS_BMAP_INVALID_PTR;
+ }
+ path[level].bp_index = index;
+ }
+ if (!found)
+ return -ENOENT;
+
+ if (ptrp != NULL)
+ *ptrp = ptr;
+
+ return 0;
+}
+
+static int nilfs_btree_do_lookup_last(const struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ __u64 *keyp, __u64 *ptrp)
+{
+ struct nilfs_btree_node *node;
+ __u64 ptr;
+ int index, level, ncmax, ret;
+
+ node = nilfs_btree_get_root(btree);
+ index = nilfs_btree_node_get_nchildren(node) - 1;
+ if (index < 0)
+ return -ENOENT;
+ level = nilfs_btree_node_get_level(node);
+ ptr = nilfs_btree_node_get_ptr(node, index,
+ NILFS_BTREE_ROOT_NCHILDREN_MAX);
+ path[level].bp_bh = NULL;
+ path[level].bp_index = index;
+ ncmax = nilfs_btree_nchildren_per_block(btree);
+
+ for (level--; level > 0; level--) {
+ ret = nilfs_btree_get_block(btree, ptr, &path[level].bp_bh);
+ if (ret < 0)
+ return ret;
+ node = nilfs_btree_get_nonroot_node(path, level);
+ if (nilfs_btree_bad_node(node, level))
+ return -EINVAL;
+ index = nilfs_btree_node_get_nchildren(node) - 1;
+ ptr = nilfs_btree_node_get_ptr(node, index, ncmax);
+ path[level].bp_index = index;
+ }
+
+ if (keyp != NULL)
+ *keyp = nilfs_btree_node_get_key(node, index);
+ if (ptrp != NULL)
+ *ptrp = ptr;
+
+ return 0;
+}
+
+/**
+ * nilfs_btree_get_next_key - get next valid key from btree path array
+ * @btree: bmap struct of btree
+ * @path: array of nilfs_btree_path struct
+ * @minlevel: start level
+ * @nextkey: place to store the next valid key
+ *
+ * Return Value: If a next key was found, 0 is returned. Otherwise,
+ * -ENOENT is returned.
+ */
+static int nilfs_btree_get_next_key(const struct nilfs_bmap *btree,
+ const struct nilfs_btree_path *path,
+ int minlevel, __u64 *nextkey)
+{
+ struct nilfs_btree_node *node;
+ int maxlevel = nilfs_btree_height(btree) - 1;
+ int index, next_adj, level;
+
+ /* Next index is already set to bp_index for leaf nodes. */
+ next_adj = 0;
+ for (level = minlevel; level <= maxlevel; level++) {
+ if (level == maxlevel)
+ node = nilfs_btree_get_root(btree);
+ else
+ node = nilfs_btree_get_nonroot_node(path, level);
+
+ index = path[level].bp_index + next_adj;
+ if (index < nilfs_btree_node_get_nchildren(node)) {
+ /* Next key is in this node */
+ *nextkey = nilfs_btree_node_get_key(node, index);
+ return 0;
+ }
+ /* For non-leaf nodes, next index is stored at bp_index + 1. */
+ next_adj = 1;
+ }
+ return -ENOENT;
+}
+
+static int nilfs_btree_lookup(const struct nilfs_bmap *btree,
+ __u64 key, int level, __u64 *ptrp)
+{
+ struct nilfs_btree_path *path;
+ int ret;
+
+ path = nilfs_btree_alloc_path();
+ if (path == NULL)
+ return -ENOMEM;
+
+ ret = nilfs_btree_do_lookup(btree, path, key, ptrp, level, 0);
+
+ nilfs_btree_free_path(path);
+
+ return ret;
+}
+
+static int nilfs_btree_lookup_contig(const struct nilfs_bmap *btree,
+ __u64 key, __u64 *ptrp, unsigned maxblocks)
+{
+ struct nilfs_btree_path *path;
+ struct nilfs_btree_node *node;
+ struct inode *dat = NULL;
+ __u64 ptr, ptr2;
+ sector_t blocknr;
+ int level = NILFS_BTREE_LEVEL_NODE_MIN;
+ int ret, cnt, index, maxlevel, ncmax;
+ struct nilfs_btree_readahead_info p;
+
+ path = nilfs_btree_alloc_path();
+ if (path == NULL)
+ return -ENOMEM;
+
+ ret = nilfs_btree_do_lookup(btree, path, key, &ptr, level, 1);
+ if (ret < 0)
+ goto out;
+
+ if (NILFS_BMAP_USE_VBN(btree)) {
+ dat = nilfs_bmap_get_dat(btree);
+ ret = nilfs_dat_translate(dat, ptr, &blocknr);
+ if (ret < 0)
+ goto out;
+ ptr = blocknr;
+ }
+ cnt = 1;
+ if (cnt == maxblocks)
+ goto end;
+
+ maxlevel = nilfs_btree_height(btree) - 1;
+ node = nilfs_btree_get_node(btree, path, level, &ncmax);
+ index = path[level].bp_index + 1;
+ for (;;) {
+ while (index < nilfs_btree_node_get_nchildren(node)) {
+ if (nilfs_btree_node_get_key(node, index) !=
+ key + cnt)
+ goto end;
+ ptr2 = nilfs_btree_node_get_ptr(node, index, ncmax);
+ if (dat) {
+ ret = nilfs_dat_translate(dat, ptr2, &blocknr);
+ if (ret < 0)
+ goto out;
+ ptr2 = blocknr;
+ }
+ if (ptr2 != ptr + cnt || ++cnt == maxblocks)
+ goto end;
+ index++;
+ continue;
+ }
+ if (level == maxlevel)
+ break;
+
+ /* look-up right sibling node */
+ p.node = nilfs_btree_get_node(btree, path, level + 1, &p.ncmax);
+ p.index = path[level + 1].bp_index + 1;
+ p.max_ra_blocks = 7;
+ if (p.index >= nilfs_btree_node_get_nchildren(p.node) ||
+ nilfs_btree_node_get_key(p.node, p.index) != key + cnt)
+ break;
+ ptr2 = nilfs_btree_node_get_ptr(p.node, p.index, p.ncmax);
+ path[level + 1].bp_index = p.index;
+
+ brelse(path[level].bp_bh);
+ path[level].bp_bh = NULL;
+
+ ret = __nilfs_btree_get_block(btree, ptr2, &path[level].bp_bh,
+ &p);
+ if (ret < 0)
+ goto out;
+ node = nilfs_btree_get_nonroot_node(path, level);
+ ncmax = nilfs_btree_nchildren_per_block(btree);
+ index = 0;
+ path[level].bp_index = index;
+ }
+ end:
+ *ptrp = ptr;
+ ret = cnt;
+ out:
+ nilfs_btree_free_path(path);
+ return ret;
+}
+
+static void nilfs_btree_promote_key(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 key)
+{
+ if (level < nilfs_btree_height(btree) - 1) {
+ do {
+ nilfs_btree_node_set_key(
+ nilfs_btree_get_nonroot_node(path, level),
+ path[level].bp_index, key);
+ if (!buffer_dirty(path[level].bp_bh))
+ mark_buffer_dirty(path[level].bp_bh);
+ } while ((path[level].bp_index == 0) &&
+ (++level < nilfs_btree_height(btree) - 1));
+ }
+
+ /* root */
+ if (level == nilfs_btree_height(btree) - 1) {
+ nilfs_btree_node_set_key(nilfs_btree_get_root(btree),
+ path[level].bp_index, key);
+ }
+}
+
+static void nilfs_btree_do_insert(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 *keyp, __u64 *ptrp)
+{
+ struct nilfs_btree_node *node;
+ int ncblk;
+
+ if (level < nilfs_btree_height(btree) - 1) {
+ node = nilfs_btree_get_nonroot_node(path, level);
+ ncblk = nilfs_btree_nchildren_per_block(btree);
+ nilfs_btree_node_insert(node, path[level].bp_index,
+ *keyp, *ptrp, ncblk);
+ if (!buffer_dirty(path[level].bp_bh))
+ mark_buffer_dirty(path[level].bp_bh);
+
+ if (path[level].bp_index == 0)
+ nilfs_btree_promote_key(btree, path, level + 1,
+ nilfs_btree_node_get_key(node,
+ 0));
+ } else {
+ node = nilfs_btree_get_root(btree);
+ nilfs_btree_node_insert(node, path[level].bp_index,
+ *keyp, *ptrp,
+ NILFS_BTREE_ROOT_NCHILDREN_MAX);
+ }
+}
+
+static void nilfs_btree_carry_left(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 *keyp, __u64 *ptrp)
+{
+ struct nilfs_btree_node *node, *left;
+ int nchildren, lnchildren, n, move, ncblk;
+
+ node = nilfs_btree_get_nonroot_node(path, level);
+ left = nilfs_btree_get_sib_node(path, level);
+ nchildren = nilfs_btree_node_get_nchildren(node);
+ lnchildren = nilfs_btree_node_get_nchildren(left);
+ ncblk = nilfs_btree_nchildren_per_block(btree);
+ move = 0;
+
+ n = (nchildren + lnchildren + 1) / 2 - lnchildren;
+ if (n > path[level].bp_index) {
+ /* move insert point */
+ n--;
+ move = 1;
+ }
+
+ nilfs_btree_node_move_left(left, node, n, ncblk, ncblk);
+
+ if (!buffer_dirty(path[level].bp_bh))
+ mark_buffer_dirty(path[level].bp_bh);
+ if (!buffer_dirty(path[level].bp_sib_bh))
+ mark_buffer_dirty(path[level].bp_sib_bh);
+
+ nilfs_btree_promote_key(btree, path, level + 1,
+ nilfs_btree_node_get_key(node, 0));
+
+ if (move) {
+ brelse(path[level].bp_bh);
+ path[level].bp_bh = path[level].bp_sib_bh;
+ path[level].bp_sib_bh = NULL;
+ path[level].bp_index += lnchildren;
+ path[level + 1].bp_index--;
+ } else {
+ brelse(path[level].bp_sib_bh);
+ path[level].bp_sib_bh = NULL;
+ path[level].bp_index -= n;
+ }
+
+ nilfs_btree_do_insert(btree, path, level, keyp, ptrp);
+}
+
+static void nilfs_btree_carry_right(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 *keyp, __u64 *ptrp)
+{
+ struct nilfs_btree_node *node, *right;
+ int nchildren, rnchildren, n, move, ncblk;
+
+ node = nilfs_btree_get_nonroot_node(path, level);
+ right = nilfs_btree_get_sib_node(path, level);
+ nchildren = nilfs_btree_node_get_nchildren(node);
+ rnchildren = nilfs_btree_node_get_nchildren(right);
+ ncblk = nilfs_btree_nchildren_per_block(btree);
+ move = 0;
+
+ n = (nchildren + rnchildren + 1) / 2 - rnchildren;
+ if (n > nchildren - path[level].bp_index) {
+ /* move insert point */
+ n--;
+ move = 1;
+ }
+
+ nilfs_btree_node_move_right(node, right, n, ncblk, ncblk);
+
+ if (!buffer_dirty(path[level].bp_bh))
+ mark_buffer_dirty(path[level].bp_bh);
+ if (!buffer_dirty(path[level].bp_sib_bh))
+ mark_buffer_dirty(path[level].bp_sib_bh);
+
+ path[level + 1].bp_index++;
+ nilfs_btree_promote_key(btree, path, level + 1,
+ nilfs_btree_node_get_key(right, 0));
+ path[level + 1].bp_index--;
+
+ if (move) {
+ brelse(path[level].bp_bh);
+ path[level].bp_bh = path[level].bp_sib_bh;
+ path[level].bp_sib_bh = NULL;
+ path[level].bp_index -= nilfs_btree_node_get_nchildren(node);
+ path[level + 1].bp_index++;
+ } else {
+ brelse(path[level].bp_sib_bh);
+ path[level].bp_sib_bh = NULL;
+ }
+
+ nilfs_btree_do_insert(btree, path, level, keyp, ptrp);
+}
+
+static void nilfs_btree_split(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 *keyp, __u64 *ptrp)
+{
+ struct nilfs_btree_node *node, *right;
+ __u64 newkey;
+ __u64 newptr;
+ int nchildren, n, move, ncblk;
+
+ node = nilfs_btree_get_nonroot_node(path, level);
+ right = nilfs_btree_get_sib_node(path, level);
+ nchildren = nilfs_btree_node_get_nchildren(node);
+ ncblk = nilfs_btree_nchildren_per_block(btree);
+ move = 0;
+
+ n = (nchildren + 1) / 2;
+ if (n > nchildren - path[level].bp_index) {
+ n--;
+ move = 1;
+ }
+
+ nilfs_btree_node_move_right(node, right, n, ncblk, ncblk);
+
+ if (!buffer_dirty(path[level].bp_bh))
+ mark_buffer_dirty(path[level].bp_bh);
+ if (!buffer_dirty(path[level].bp_sib_bh))
+ mark_buffer_dirty(path[level].bp_sib_bh);
+
+ newkey = nilfs_btree_node_get_key(right, 0);
+ newptr = path[level].bp_newreq.bpr_ptr;
+
+ if (move) {
+ path[level].bp_index -= nilfs_btree_node_get_nchildren(node);
+ nilfs_btree_node_insert(right, path[level].bp_index,
+ *keyp, *ptrp, ncblk);
+
+ *keyp = nilfs_btree_node_get_key(right, 0);
+ *ptrp = path[level].bp_newreq.bpr_ptr;
+
+ brelse(path[level].bp_bh);
+ path[level].bp_bh = path[level].bp_sib_bh;
+ path[level].bp_sib_bh = NULL;
+ } else {
+ nilfs_btree_do_insert(btree, path, level, keyp, ptrp);
+
+ *keyp = nilfs_btree_node_get_key(right, 0);
+ *ptrp = path[level].bp_newreq.bpr_ptr;
+
+ brelse(path[level].bp_sib_bh);
+ path[level].bp_sib_bh = NULL;
+ }
+
+ path[level + 1].bp_index++;
+}
+
+static void nilfs_btree_grow(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 *keyp, __u64 *ptrp)
+{
+ struct nilfs_btree_node *root, *child;
+ int n, ncblk;
+
+ root = nilfs_btree_get_root(btree);
+ child = nilfs_btree_get_sib_node(path, level);
+ ncblk = nilfs_btree_nchildren_per_block(btree);
+
+ n = nilfs_btree_node_get_nchildren(root);
+
+ nilfs_btree_node_move_right(root, child, n,
+ NILFS_BTREE_ROOT_NCHILDREN_MAX, ncblk);
+ nilfs_btree_node_set_level(root, level + 1);
+
+ if (!buffer_dirty(path[level].bp_sib_bh))
+ mark_buffer_dirty(path[level].bp_sib_bh);
+
+ path[level].bp_bh = path[level].bp_sib_bh;
+ path[level].bp_sib_bh = NULL;
+
+ nilfs_btree_do_insert(btree, path, level, keyp, ptrp);
+
+ *keyp = nilfs_btree_node_get_key(child, 0);
+ *ptrp = path[level].bp_newreq.bpr_ptr;
+}
+
+static __u64 nilfs_btree_find_near(const struct nilfs_bmap *btree,
+ const struct nilfs_btree_path *path)
+{
+ struct nilfs_btree_node *node;
+ int level, ncmax;
+
+ if (path == NULL)
+ return NILFS_BMAP_INVALID_PTR;
+
+ /* left sibling */
+ level = NILFS_BTREE_LEVEL_NODE_MIN;
+ if (path[level].bp_index > 0) {
+ node = nilfs_btree_get_node(btree, path, level, &ncmax);
+ return nilfs_btree_node_get_ptr(node,
+ path[level].bp_index - 1,
+ ncmax);
+ }
+
+ /* parent */
+ level = NILFS_BTREE_LEVEL_NODE_MIN + 1;
+ if (level <= nilfs_btree_height(btree) - 1) {
+ node = nilfs_btree_get_node(btree, path, level, &ncmax);
+ return nilfs_btree_node_get_ptr(node, path[level].bp_index,
+ ncmax);
+ }
+
+ return NILFS_BMAP_INVALID_PTR;
+}
+
+static __u64 nilfs_btree_find_target_v(const struct nilfs_bmap *btree,
+ const struct nilfs_btree_path *path,
+ __u64 key)
+{
+ __u64 ptr;
+
+ ptr = nilfs_bmap_find_target_seq(btree, key);
+ if (ptr != NILFS_BMAP_INVALID_PTR)
+ /* sequential access */
+ return ptr;
+ else {
+ ptr = nilfs_btree_find_near(btree, path);
+ if (ptr != NILFS_BMAP_INVALID_PTR)
+ /* near */
+ return ptr;
+ }
+ /* block group */
+ return nilfs_bmap_find_target_in_group(btree);
+}
+
+static int nilfs_btree_prepare_insert(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int *levelp, __u64 key, __u64 ptr,
+ struct nilfs_bmap_stats *stats)
+{
+ struct buffer_head *bh;
+ struct nilfs_btree_node *node, *parent, *sib;
+ __u64 sibptr;
+ int pindex, level, ncmax, ncblk, ret;
+ struct inode *dat = NULL;
+
+ stats->bs_nblocks = 0;
+ level = NILFS_BTREE_LEVEL_DATA;
+
+ /* allocate a new ptr for data block */
+ if (NILFS_BMAP_USE_VBN(btree)) {
+ path[level].bp_newreq.bpr_ptr =
+ nilfs_btree_find_target_v(btree, path, key);
+ dat = nilfs_bmap_get_dat(btree);
+ }
+
+ ret = nilfs_bmap_prepare_alloc_ptr(btree, &path[level].bp_newreq, dat);
+ if (ret < 0)
+ goto err_out_data;
+
+ ncblk = nilfs_btree_nchildren_per_block(btree);
+
+ for (level = NILFS_BTREE_LEVEL_NODE_MIN;
+ level < nilfs_btree_height(btree) - 1;
+ level++) {
+ node = nilfs_btree_get_nonroot_node(path, level);
+ if (nilfs_btree_node_get_nchildren(node) < ncblk) {
+ path[level].bp_op = nilfs_btree_do_insert;
+ stats->bs_nblocks++;
+ goto out;
+ }
+
+ parent = nilfs_btree_get_node(btree, path, level + 1, &ncmax);
+ pindex = path[level + 1].bp_index;
+
+ /* left sibling */
+ if (pindex > 0) {
+ sibptr = nilfs_btree_node_get_ptr(parent, pindex - 1,
+ ncmax);
+ ret = nilfs_btree_get_block(btree, sibptr, &bh);
+ if (ret < 0)
+ goto err_out_child_node;
+ sib = (struct nilfs_btree_node *)bh->b_data;
+ if (nilfs_btree_node_get_nchildren(sib) < ncblk) {
+ path[level].bp_sib_bh = bh;
+ path[level].bp_op = nilfs_btree_carry_left;
+ stats->bs_nblocks++;
+ goto out;
+ } else {
+ brelse(bh);
+ }
+ }
+
+ /* right sibling */
+ if (pindex < nilfs_btree_node_get_nchildren(parent) - 1) {
+ sibptr = nilfs_btree_node_get_ptr(parent, pindex + 1,
+ ncmax);
+ ret = nilfs_btree_get_block(btree, sibptr, &bh);
+ if (ret < 0)
+ goto err_out_child_node;
+ sib = (struct nilfs_btree_node *)bh->b_data;
+ if (nilfs_btree_node_get_nchildren(sib) < ncblk) {
+ path[level].bp_sib_bh = bh;
+ path[level].bp_op = nilfs_btree_carry_right;
+ stats->bs_nblocks++;
+ goto out;
+ } else {
+ brelse(bh);
+ }
+ }
+
+ /* split */
+ path[level].bp_newreq.bpr_ptr =
+ path[level - 1].bp_newreq.bpr_ptr + 1;
+ ret = nilfs_bmap_prepare_alloc_ptr(btree,
+ &path[level].bp_newreq, dat);
+ if (ret < 0)
+ goto err_out_child_node;
+ ret = nilfs_btree_get_new_block(btree,
+ path[level].bp_newreq.bpr_ptr,
+ &bh);
+ if (ret < 0)
+ goto err_out_curr_node;
+
+ stats->bs_nblocks++;
+
+ sib = (struct nilfs_btree_node *)bh->b_data;
+ nilfs_btree_node_init(sib, 0, level, 0, ncblk, NULL, NULL);
+ path[level].bp_sib_bh = bh;
+ path[level].bp_op = nilfs_btree_split;
+ }
+
+ /* root */
+ node = nilfs_btree_get_root(btree);
+ if (nilfs_btree_node_get_nchildren(node) <
+ NILFS_BTREE_ROOT_NCHILDREN_MAX) {
+ path[level].bp_op = nilfs_btree_do_insert;
+ stats->bs_nblocks++;
+ goto out;
+ }
+
+ /* grow */
+ path[level].bp_newreq.bpr_ptr = path[level - 1].bp_newreq.bpr_ptr + 1;
+ ret = nilfs_bmap_prepare_alloc_ptr(btree, &path[level].bp_newreq, dat);
+ if (ret < 0)
+ goto err_out_child_node;
+ ret = nilfs_btree_get_new_block(btree, path[level].bp_newreq.bpr_ptr,
+ &bh);
+ if (ret < 0)
+ goto err_out_curr_node;
+
+ nilfs_btree_node_init((struct nilfs_btree_node *)bh->b_data,
+ 0, level, 0, ncblk, NULL, NULL);
+ path[level].bp_sib_bh = bh;
+ path[level].bp_op = nilfs_btree_grow;
+
+ level++;
+ path[level].bp_op = nilfs_btree_do_insert;
+
+ /* a newly-created node block and a data block are added */
+ stats->bs_nblocks += 2;
+
+ /* success */
+ out:
+ *levelp = level;
+ return ret;
+
+ /* error */
+ err_out_curr_node:
+ nilfs_bmap_abort_alloc_ptr(btree, &path[level].bp_newreq, dat);
+ err_out_child_node:
+ for (level--; level > NILFS_BTREE_LEVEL_DATA; level--) {
+ nilfs_btnode_delete(path[level].bp_sib_bh);
+ nilfs_bmap_abort_alloc_ptr(btree, &path[level].bp_newreq, dat);
+
+ }
+
+ nilfs_bmap_abort_alloc_ptr(btree, &path[level].bp_newreq, dat);
+ err_out_data:
+ *levelp = level;
+ stats->bs_nblocks = 0;
+ return ret;
+}
+
+static void nilfs_btree_commit_insert(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int maxlevel, __u64 key, __u64 ptr)
+{
+ struct inode *dat = NULL;
+ int level;
+
+ set_buffer_nilfs_volatile((struct buffer_head *)((unsigned long)ptr));
+ ptr = path[NILFS_BTREE_LEVEL_DATA].bp_newreq.bpr_ptr;
+ if (NILFS_BMAP_USE_VBN(btree)) {
+ nilfs_bmap_set_target_v(btree, key, ptr);
+ dat = nilfs_bmap_get_dat(btree);
+ }
+
+ for (level = NILFS_BTREE_LEVEL_NODE_MIN; level <= maxlevel; level++) {
+ nilfs_bmap_commit_alloc_ptr(btree,
+ &path[level - 1].bp_newreq, dat);
+ path[level].bp_op(btree, path, level, &key, &ptr);
+ }
+
+ if (!nilfs_bmap_dirty(btree))
+ nilfs_bmap_set_dirty(btree);
+}
+
+static int nilfs_btree_insert(struct nilfs_bmap *btree, __u64 key, __u64 ptr)
+{
+ struct nilfs_btree_path *path;
+ struct nilfs_bmap_stats stats;
+ int level, ret;
+
+ path = nilfs_btree_alloc_path();
+ if (path == NULL)
+ return -ENOMEM;
+
+ ret = nilfs_btree_do_lookup(btree, path, key, NULL,
+ NILFS_BTREE_LEVEL_NODE_MIN, 0);
+ if (ret != -ENOENT) {
+ if (ret == 0)
+ ret = -EEXIST;
+ goto out;
+ }
+
+ ret = nilfs_btree_prepare_insert(btree, path, &level, key, ptr, &stats);
+ if (ret < 0)
+ goto out;
+ nilfs_btree_commit_insert(btree, path, level, key, ptr);
+ nilfs_inode_add_blocks(btree->b_inode, stats.bs_nblocks);
+
+ out:
+ nilfs_btree_free_path(path);
+ return ret;
+}
+
+static void nilfs_btree_do_delete(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 *keyp, __u64 *ptrp)
+{
+ struct nilfs_btree_node *node;
+ int ncblk;
+
+ if (level < nilfs_btree_height(btree) - 1) {
+ node = nilfs_btree_get_nonroot_node(path, level);
+ ncblk = nilfs_btree_nchildren_per_block(btree);
+ nilfs_btree_node_delete(node, path[level].bp_index,
+ keyp, ptrp, ncblk);
+ if (!buffer_dirty(path[level].bp_bh))
+ mark_buffer_dirty(path[level].bp_bh);
+ if (path[level].bp_index == 0)
+ nilfs_btree_promote_key(btree, path, level + 1,
+ nilfs_btree_node_get_key(node, 0));
+ } else {
+ node = nilfs_btree_get_root(btree);
+ nilfs_btree_node_delete(node, path[level].bp_index,
+ keyp, ptrp,
+ NILFS_BTREE_ROOT_NCHILDREN_MAX);
+ }
+}
+
+static void nilfs_btree_borrow_left(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 *keyp, __u64 *ptrp)
+{
+ struct nilfs_btree_node *node, *left;
+ int nchildren, lnchildren, n, ncblk;
+
+ nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
+
+ node = nilfs_btree_get_nonroot_node(path, level);
+ left = nilfs_btree_get_sib_node(path, level);
+ nchildren = nilfs_btree_node_get_nchildren(node);
+ lnchildren = nilfs_btree_node_get_nchildren(left);
+ ncblk = nilfs_btree_nchildren_per_block(btree);
+
+ n = (nchildren + lnchildren) / 2 - nchildren;
+
+ nilfs_btree_node_move_right(left, node, n, ncblk, ncblk);
+
+ if (!buffer_dirty(path[level].bp_bh))
+ mark_buffer_dirty(path[level].bp_bh);
+ if (!buffer_dirty(path[level].bp_sib_bh))
+ mark_buffer_dirty(path[level].bp_sib_bh);
+
+ nilfs_btree_promote_key(btree, path, level + 1,
+ nilfs_btree_node_get_key(node, 0));
+
+ brelse(path[level].bp_sib_bh);
+ path[level].bp_sib_bh = NULL;
+ path[level].bp_index += n;
+}
+
+static void nilfs_btree_borrow_right(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 *keyp, __u64 *ptrp)
+{
+ struct nilfs_btree_node *node, *right;
+ int nchildren, rnchildren, n, ncblk;
+
+ nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
+
+ node = nilfs_btree_get_nonroot_node(path, level);
+ right = nilfs_btree_get_sib_node(path, level);
+ nchildren = nilfs_btree_node_get_nchildren(node);
+ rnchildren = nilfs_btree_node_get_nchildren(right);
+ ncblk = nilfs_btree_nchildren_per_block(btree);
+
+ n = (nchildren + rnchildren) / 2 - nchildren;
+
+ nilfs_btree_node_move_left(node, right, n, ncblk, ncblk);
+
+ if (!buffer_dirty(path[level].bp_bh))
+ mark_buffer_dirty(path[level].bp_bh);
+ if (!buffer_dirty(path[level].bp_sib_bh))
+ mark_buffer_dirty(path[level].bp_sib_bh);
+
+ path[level + 1].bp_index++;
+ nilfs_btree_promote_key(btree, path, level + 1,
+ nilfs_btree_node_get_key(right, 0));
+ path[level + 1].bp_index--;
+
+ brelse(path[level].bp_sib_bh);
+ path[level].bp_sib_bh = NULL;
+}
+
+static void nilfs_btree_concat_left(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 *keyp, __u64 *ptrp)
+{
+ struct nilfs_btree_node *node, *left;
+ int n, ncblk;
+
+ nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
+
+ node = nilfs_btree_get_nonroot_node(path, level);
+ left = nilfs_btree_get_sib_node(path, level);
+ ncblk = nilfs_btree_nchildren_per_block(btree);
+
+ n = nilfs_btree_node_get_nchildren(node);
+
+ nilfs_btree_node_move_left(left, node, n, ncblk, ncblk);
+
+ if (!buffer_dirty(path[level].bp_sib_bh))
+ mark_buffer_dirty(path[level].bp_sib_bh);
+
+ nilfs_btnode_delete(path[level].bp_bh);
+ path[level].bp_bh = path[level].bp_sib_bh;
+ path[level].bp_sib_bh = NULL;
+ path[level].bp_index += nilfs_btree_node_get_nchildren(left);
+}
+
+static void nilfs_btree_concat_right(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 *keyp, __u64 *ptrp)
+{
+ struct nilfs_btree_node *node, *right;
+ int n, ncblk;
+
+ nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
+
+ node = nilfs_btree_get_nonroot_node(path, level);
+ right = nilfs_btree_get_sib_node(path, level);
+ ncblk = nilfs_btree_nchildren_per_block(btree);
+
+ n = nilfs_btree_node_get_nchildren(right);
+
+ nilfs_btree_node_move_left(node, right, n, ncblk, ncblk);
+
+ if (!buffer_dirty(path[level].bp_bh))
+ mark_buffer_dirty(path[level].bp_bh);
+
+ nilfs_btnode_delete(path[level].bp_sib_bh);
+ path[level].bp_sib_bh = NULL;
+ path[level + 1].bp_index++;
+}
+
+static void nilfs_btree_shrink(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 *keyp, __u64 *ptrp)
+{
+ struct nilfs_btree_node *root, *child;
+ int n, ncblk;
+
+ nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
+
+ root = nilfs_btree_get_root(btree);
+ child = nilfs_btree_get_nonroot_node(path, level);
+ ncblk = nilfs_btree_nchildren_per_block(btree);
+
+ nilfs_btree_node_delete(root, 0, NULL, NULL,
+ NILFS_BTREE_ROOT_NCHILDREN_MAX);
+ nilfs_btree_node_set_level(root, level);
+ n = nilfs_btree_node_get_nchildren(child);
+ nilfs_btree_node_move_left(root, child, n,
+ NILFS_BTREE_ROOT_NCHILDREN_MAX, ncblk);
+
+ nilfs_btnode_delete(path[level].bp_bh);
+ path[level].bp_bh = NULL;
+}
+
+static void nilfs_btree_nop(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 *keyp, __u64 *ptrp)
+{
+}
+
+static int nilfs_btree_prepare_delete(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int *levelp,
+ struct nilfs_bmap_stats *stats,
+ struct inode *dat)
+{
+ struct buffer_head *bh;
+ struct nilfs_btree_node *node, *parent, *sib;
+ __u64 sibptr;
+ int pindex, dindex, level, ncmin, ncmax, ncblk, ret;
+
+ ret = 0;
+ stats->bs_nblocks = 0;
+ ncmin = NILFS_BTREE_NODE_NCHILDREN_MIN(nilfs_btree_node_size(btree));
+ ncblk = nilfs_btree_nchildren_per_block(btree);
+
+ for (level = NILFS_BTREE_LEVEL_NODE_MIN, dindex = path[level].bp_index;
+ level < nilfs_btree_height(btree) - 1;
+ level++) {
+ node = nilfs_btree_get_nonroot_node(path, level);
+ path[level].bp_oldreq.bpr_ptr =
+ nilfs_btree_node_get_ptr(node, dindex, ncblk);
+ ret = nilfs_bmap_prepare_end_ptr(btree,
+ &path[level].bp_oldreq, dat);
+ if (ret < 0)
+ goto err_out_child_node;
+
+ if (nilfs_btree_node_get_nchildren(node) > ncmin) {
+ path[level].bp_op = nilfs_btree_do_delete;
+ stats->bs_nblocks++;
+ goto out;
+ }
+
+ parent = nilfs_btree_get_node(btree, path, level + 1, &ncmax);
+ pindex = path[level + 1].bp_index;
+ dindex = pindex;
+
+ if (pindex > 0) {
+ /* left sibling */
+ sibptr = nilfs_btree_node_get_ptr(parent, pindex - 1,
+ ncmax);
+ ret = nilfs_btree_get_block(btree, sibptr, &bh);
+ if (ret < 0)
+ goto err_out_curr_node;
+ sib = (struct nilfs_btree_node *)bh->b_data;
+ if (nilfs_btree_node_get_nchildren(sib) > ncmin) {
+ path[level].bp_sib_bh = bh;
+ path[level].bp_op = nilfs_btree_borrow_left;
+ stats->bs_nblocks++;
+ goto out;
+ } else {
+ path[level].bp_sib_bh = bh;
+ path[level].bp_op = nilfs_btree_concat_left;
+ stats->bs_nblocks++;
+ /* continue; */
+ }
+ } else if (pindex <
+ nilfs_btree_node_get_nchildren(parent) - 1) {
+ /* right sibling */
+ sibptr = nilfs_btree_node_get_ptr(parent, pindex + 1,
+ ncmax);
+ ret = nilfs_btree_get_block(btree, sibptr, &bh);
+ if (ret < 0)
+ goto err_out_curr_node;
+ sib = (struct nilfs_btree_node *)bh->b_data;
+ if (nilfs_btree_node_get_nchildren(sib) > ncmin) {
+ path[level].bp_sib_bh = bh;
+ path[level].bp_op = nilfs_btree_borrow_right;
+ stats->bs_nblocks++;
+ goto out;
+ } else {
+ path[level].bp_sib_bh = bh;
+ path[level].bp_op = nilfs_btree_concat_right;
+ stats->bs_nblocks++;
+ /*
+ * When merging right sibling node
+ * into the current node, pointer to
+ * the right sibling node must be
+ * terminated instead. The adjustment
+ * below is required for that.
+ */
+ dindex = pindex + 1;
+ /* continue; */
+ }
+ } else {
+ /* no siblings */
+ /* the only child of the root node */
+ WARN_ON(level != nilfs_btree_height(btree) - 2);
+ if (nilfs_btree_node_get_nchildren(node) - 1 <=
+ NILFS_BTREE_ROOT_NCHILDREN_MAX) {
+ path[level].bp_op = nilfs_btree_shrink;
+ stats->bs_nblocks += 2;
+ level++;
+ path[level].bp_op = nilfs_btree_nop;
+ goto shrink_root_child;
+ } else {
+ path[level].bp_op = nilfs_btree_do_delete;
+ stats->bs_nblocks++;
+ goto out;
+ }
+ }
+ }
+
+ /* child of the root node is deleted */
+ path[level].bp_op = nilfs_btree_do_delete;
+ stats->bs_nblocks++;
+
+shrink_root_child:
+ node = nilfs_btree_get_root(btree);
+ path[level].bp_oldreq.bpr_ptr =
+ nilfs_btree_node_get_ptr(node, dindex,
+ NILFS_BTREE_ROOT_NCHILDREN_MAX);
+
+ ret = nilfs_bmap_prepare_end_ptr(btree, &path[level].bp_oldreq, dat);
+ if (ret < 0)
+ goto err_out_child_node;
+
+ /* success */
+ out:
+ *levelp = level;
+ return ret;
+
+ /* error */
+ err_out_curr_node:
+ nilfs_bmap_abort_end_ptr(btree, &path[level].bp_oldreq, dat);
+ err_out_child_node:
+ for (level--; level >= NILFS_BTREE_LEVEL_NODE_MIN; level--) {
+ brelse(path[level].bp_sib_bh);
+ nilfs_bmap_abort_end_ptr(btree, &path[level].bp_oldreq, dat);
+ }
+ *levelp = level;
+ stats->bs_nblocks = 0;
+ return ret;
+}
+
+static void nilfs_btree_commit_delete(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int maxlevel, struct inode *dat)
+{
+ int level;
+
+ for (level = NILFS_BTREE_LEVEL_NODE_MIN; level <= maxlevel; level++) {
+ nilfs_bmap_commit_end_ptr(btree, &path[level].bp_oldreq, dat);
+ path[level].bp_op(btree, path, level, NULL, NULL);
+ }
+
+ if (!nilfs_bmap_dirty(btree))
+ nilfs_bmap_set_dirty(btree);
+}
+
+static int nilfs_btree_delete(struct nilfs_bmap *btree, __u64 key)
+
+{
+ struct nilfs_btree_path *path;
+ struct nilfs_bmap_stats stats;
+ struct inode *dat;
+ int level, ret;
+
+ path = nilfs_btree_alloc_path();
+ if (path == NULL)
+ return -ENOMEM;
+
+ ret = nilfs_btree_do_lookup(btree, path, key, NULL,
+ NILFS_BTREE_LEVEL_NODE_MIN, 0);
+ if (ret < 0)
+ goto out;
+
+
+ dat = NILFS_BMAP_USE_VBN(btree) ? nilfs_bmap_get_dat(btree) : NULL;
+
+ ret = nilfs_btree_prepare_delete(btree, path, &level, &stats, dat);
+ if (ret < 0)
+ goto out;
+ nilfs_btree_commit_delete(btree, path, level, dat);
+ nilfs_inode_sub_blocks(btree->b_inode, stats.bs_nblocks);
+
+out:
+ nilfs_btree_free_path(path);
+ return ret;
+}
+
+static int nilfs_btree_seek_key(const struct nilfs_bmap *btree, __u64 start,
+ __u64 *keyp)
+{
+ struct nilfs_btree_path *path;
+ const int minlevel = NILFS_BTREE_LEVEL_NODE_MIN;
+ int ret;
+
+ path = nilfs_btree_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ ret = nilfs_btree_do_lookup(btree, path, start, NULL, minlevel, 0);
+ if (!ret)
+ *keyp = start;
+ else if (ret == -ENOENT)
+ ret = nilfs_btree_get_next_key(btree, path, minlevel, keyp);
+
+ nilfs_btree_free_path(path);
+ return ret;
+}
+
+static int nilfs_btree_last_key(const struct nilfs_bmap *btree, __u64 *keyp)
+{
+ struct nilfs_btree_path *path;
+ int ret;
+
+ path = nilfs_btree_alloc_path();
+ if (path == NULL)
+ return -ENOMEM;
+
+ ret = nilfs_btree_do_lookup_last(btree, path, keyp, NULL);
+
+ nilfs_btree_free_path(path);
+
+ return ret;
+}
+
+static int nilfs_btree_check_delete(struct nilfs_bmap *btree, __u64 key)
+{
+ struct buffer_head *bh;
+ struct nilfs_btree_node *root, *node;
+ __u64 maxkey, nextmaxkey;
+ __u64 ptr;
+ int nchildren, ret;
+
+ root = nilfs_btree_get_root(btree);
+ switch (nilfs_btree_height(btree)) {
+ case 2:
+ bh = NULL;
+ node = root;
+ break;
+ case 3:
+ nchildren = nilfs_btree_node_get_nchildren(root);
+ if (nchildren > 1)
+ return 0;
+ ptr = nilfs_btree_node_get_ptr(root, nchildren - 1,
+ NILFS_BTREE_ROOT_NCHILDREN_MAX);
+ ret = nilfs_btree_get_block(btree, ptr, &bh);
+ if (ret < 0)
+ return ret;
+ node = (struct nilfs_btree_node *)bh->b_data;
+ break;
+ default:
+ return 0;
+ }
+
+ nchildren = nilfs_btree_node_get_nchildren(node);
+ maxkey = nilfs_btree_node_get_key(node, nchildren - 1);
+ nextmaxkey = (nchildren > 1) ?
+ nilfs_btree_node_get_key(node, nchildren - 2) : 0;
+ if (bh != NULL)
+ brelse(bh);
+
+ return (maxkey == key) && (nextmaxkey < NILFS_BMAP_LARGE_LOW);
+}
+
+static int nilfs_btree_gather_data(struct nilfs_bmap *btree,
+ __u64 *keys, __u64 *ptrs, int nitems)
+{
+ struct buffer_head *bh;
+ struct nilfs_btree_node *node, *root;
+ __le64 *dkeys;
+ __le64 *dptrs;
+ __u64 ptr;
+ int nchildren, ncmax, i, ret;
+
+ root = nilfs_btree_get_root(btree);
+ switch (nilfs_btree_height(btree)) {
+ case 2:
+ bh = NULL;
+ node = root;
+ ncmax = NILFS_BTREE_ROOT_NCHILDREN_MAX;
+ break;
+ case 3:
+ nchildren = nilfs_btree_node_get_nchildren(root);
+ WARN_ON(nchildren > 1);
+ ptr = nilfs_btree_node_get_ptr(root, nchildren - 1,
+ NILFS_BTREE_ROOT_NCHILDREN_MAX);
+ ret = nilfs_btree_get_block(btree, ptr, &bh);
+ if (ret < 0)
+ return ret;
+ node = (struct nilfs_btree_node *)bh->b_data;
+ ncmax = nilfs_btree_nchildren_per_block(btree);
+ break;
+ default:
+ node = NULL;
+ return -EINVAL;
+ }
+
+ nchildren = nilfs_btree_node_get_nchildren(node);
+ if (nchildren < nitems)
+ nitems = nchildren;
+ dkeys = nilfs_btree_node_dkeys(node);
+ dptrs = nilfs_btree_node_dptrs(node, ncmax);
+ for (i = 0; i < nitems; i++) {
+ keys[i] = le64_to_cpu(dkeys[i]);
+ ptrs[i] = le64_to_cpu(dptrs[i]);
+ }
+
+ if (bh != NULL)
+ brelse(bh);
+
+ return nitems;
+}
+
+static int
+nilfs_btree_prepare_convert_and_insert(struct nilfs_bmap *btree, __u64 key,
+ union nilfs_bmap_ptr_req *dreq,
+ union nilfs_bmap_ptr_req *nreq,
+ struct buffer_head **bhp,
+ struct nilfs_bmap_stats *stats)
+{
+ struct buffer_head *bh;
+ struct inode *dat = NULL;
+ int ret;
+
+ stats->bs_nblocks = 0;
+
+ /* for data */
+ /* cannot find near ptr */
+ if (NILFS_BMAP_USE_VBN(btree)) {
+ dreq->bpr_ptr = nilfs_btree_find_target_v(btree, NULL, key);
+ dat = nilfs_bmap_get_dat(btree);
+ }
+
+ ret = nilfs_bmap_prepare_alloc_ptr(btree, dreq, dat);
+ if (ret < 0)
+ return ret;
+
+ *bhp = NULL;
+ stats->bs_nblocks++;
+ if (nreq != NULL) {
+ nreq->bpr_ptr = dreq->bpr_ptr + 1;
+ ret = nilfs_bmap_prepare_alloc_ptr(btree, nreq, dat);
+ if (ret < 0)
+ goto err_out_dreq;
+
+ ret = nilfs_btree_get_new_block(btree, nreq->bpr_ptr, &bh);
+ if (ret < 0)
+ goto err_out_nreq;
+
+ *bhp = bh;
+ stats->bs_nblocks++;
+ }
+
+ /* success */
+ return 0;
+
+ /* error */
+ err_out_nreq:
+ nilfs_bmap_abort_alloc_ptr(btree, nreq, dat);
+ err_out_dreq:
+ nilfs_bmap_abort_alloc_ptr(btree, dreq, dat);
+ stats->bs_nblocks = 0;
+ return ret;
+
+}
+
+static void
+nilfs_btree_commit_convert_and_insert(struct nilfs_bmap *btree,
+ __u64 key, __u64 ptr,
+ const __u64 *keys, const __u64 *ptrs,
+ int n,
+ union nilfs_bmap_ptr_req *dreq,
+ union nilfs_bmap_ptr_req *nreq,
+ struct buffer_head *bh)
+{
+ struct nilfs_btree_node *node;
+ struct inode *dat;
+ __u64 tmpptr;
+ int ncblk;
+
+ /* free resources */
+ if (btree->b_ops->bop_clear != NULL)
+ btree->b_ops->bop_clear(btree);
+
+ /* ptr must be a pointer to a buffer head. */
+ set_buffer_nilfs_volatile((struct buffer_head *)((unsigned long)ptr));
+
+ /* convert and insert */
+ dat = NILFS_BMAP_USE_VBN(btree) ? nilfs_bmap_get_dat(btree) : NULL;
+ __nilfs_btree_init(btree);
+ if (nreq != NULL) {
+ nilfs_bmap_commit_alloc_ptr(btree, dreq, dat);
+ nilfs_bmap_commit_alloc_ptr(btree, nreq, dat);
+
+ /* create child node at level 1 */
+ node = (struct nilfs_btree_node *)bh->b_data;
+ ncblk = nilfs_btree_nchildren_per_block(btree);
+ nilfs_btree_node_init(node, 0, 1, n, ncblk, keys, ptrs);
+ nilfs_btree_node_insert(node, n, key, dreq->bpr_ptr, ncblk);
+ if (!buffer_dirty(bh))
+ mark_buffer_dirty(bh);
+ if (!nilfs_bmap_dirty(btree))
+ nilfs_bmap_set_dirty(btree);
+
+ brelse(bh);
+
+ /* create root node at level 2 */
+ node = nilfs_btree_get_root(btree);
+ tmpptr = nreq->bpr_ptr;
+ nilfs_btree_node_init(node, NILFS_BTREE_NODE_ROOT, 2, 1,
+ NILFS_BTREE_ROOT_NCHILDREN_MAX,
+ &keys[0], &tmpptr);
+ } else {
+ nilfs_bmap_commit_alloc_ptr(btree, dreq, dat);
+
+ /* create root node at level 1 */
+ node = nilfs_btree_get_root(btree);
+ nilfs_btree_node_init(node, NILFS_BTREE_NODE_ROOT, 1, n,
+ NILFS_BTREE_ROOT_NCHILDREN_MAX,
+ keys, ptrs);
+ nilfs_btree_node_insert(node, n, key, dreq->bpr_ptr,
+ NILFS_BTREE_ROOT_NCHILDREN_MAX);
+ if (!nilfs_bmap_dirty(btree))
+ nilfs_bmap_set_dirty(btree);
+ }
+
+ if (NILFS_BMAP_USE_VBN(btree))
+ nilfs_bmap_set_target_v(btree, key, dreq->bpr_ptr);
+}
+
+/**
+ * nilfs_btree_convert_and_insert -
+ * @bmap:
+ * @key:
+ * @ptr:
+ * @keys:
+ * @ptrs:
+ * @n:
+ */
+int nilfs_btree_convert_and_insert(struct nilfs_bmap *btree,
+ __u64 key, __u64 ptr,
+ const __u64 *keys, const __u64 *ptrs, int n)
+{
+ struct buffer_head *bh;
+ union nilfs_bmap_ptr_req dreq, nreq, *di, *ni;
+ struct nilfs_bmap_stats stats;
+ int ret;
+
+ if (n + 1 <= NILFS_BTREE_ROOT_NCHILDREN_MAX) {
+ di = &dreq;
+ ni = NULL;
+ } else if ((n + 1) <= NILFS_BTREE_NODE_NCHILDREN_MAX(
+ 1 << btree->b_inode->i_blkbits)) {
+ di = &dreq;
+ ni = &nreq;
+ } else {
+ di = NULL;
+ ni = NULL;
+ BUG();
+ }
+
+ ret = nilfs_btree_prepare_convert_and_insert(btree, key, di, ni, &bh,
+ &stats);
+ if (ret < 0)
+ return ret;
+ nilfs_btree_commit_convert_and_insert(btree, key, ptr, keys, ptrs, n,
+ di, ni, bh);
+ nilfs_inode_add_blocks(btree->b_inode, stats.bs_nblocks);
+ return 0;
+}
+
+static int nilfs_btree_propagate_p(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int level,
+ struct buffer_head *bh)
+{
+ while ((++level < nilfs_btree_height(btree) - 1) &&
+ !buffer_dirty(path[level].bp_bh))
+ mark_buffer_dirty(path[level].bp_bh);
+
+ return 0;
+}
+
+static int nilfs_btree_prepare_update_v(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int level, struct inode *dat)
+{
+ struct nilfs_btree_node *parent;
+ int ncmax, ret;
+
+ parent = nilfs_btree_get_node(btree, path, level + 1, &ncmax);
+ path[level].bp_oldreq.bpr_ptr =
+ nilfs_btree_node_get_ptr(parent, path[level + 1].bp_index,
+ ncmax);
+ path[level].bp_newreq.bpr_ptr = path[level].bp_oldreq.bpr_ptr + 1;
+ ret = nilfs_dat_prepare_update(dat, &path[level].bp_oldreq.bpr_req,
+ &path[level].bp_newreq.bpr_req);
+ if (ret < 0)
+ return ret;
+
+ if (buffer_nilfs_node(path[level].bp_bh)) {
+ path[level].bp_ctxt.oldkey = path[level].bp_oldreq.bpr_ptr;
+ path[level].bp_ctxt.newkey = path[level].bp_newreq.bpr_ptr;
+ path[level].bp_ctxt.bh = path[level].bp_bh;
+ ret = nilfs_btnode_prepare_change_key(
+ &NILFS_BMAP_I(btree)->i_btnode_cache,
+ &path[level].bp_ctxt);
+ if (ret < 0) {
+ nilfs_dat_abort_update(dat,
+ &path[level].bp_oldreq.bpr_req,
+ &path[level].bp_newreq.bpr_req);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static void nilfs_btree_commit_update_v(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int level, struct inode *dat)
+{
+ struct nilfs_btree_node *parent;
+ int ncmax;
+
+ nilfs_dat_commit_update(dat, &path[level].bp_oldreq.bpr_req,
+ &path[level].bp_newreq.bpr_req,
+ btree->b_ptr_type == NILFS_BMAP_PTR_VS);
+
+ if (buffer_nilfs_node(path[level].bp_bh)) {
+ nilfs_btnode_commit_change_key(
+ &NILFS_BMAP_I(btree)->i_btnode_cache,
+ &path[level].bp_ctxt);
+ path[level].bp_bh = path[level].bp_ctxt.bh;
+ }
+ set_buffer_nilfs_volatile(path[level].bp_bh);
+
+ parent = nilfs_btree_get_node(btree, path, level + 1, &ncmax);
+ nilfs_btree_node_set_ptr(parent, path[level + 1].bp_index,
+ path[level].bp_newreq.bpr_ptr, ncmax);
+}
+
+static void nilfs_btree_abort_update_v(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int level, struct inode *dat)
+{
+ nilfs_dat_abort_update(dat, &path[level].bp_oldreq.bpr_req,
+ &path[level].bp_newreq.bpr_req);
+ if (buffer_nilfs_node(path[level].bp_bh))
+ nilfs_btnode_abort_change_key(
+ &NILFS_BMAP_I(btree)->i_btnode_cache,
+ &path[level].bp_ctxt);
+}
+
+static int nilfs_btree_prepare_propagate_v(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int minlevel, int *maxlevelp,
+ struct inode *dat)
+{
+ int level, ret;
+
+ level = minlevel;
+ if (!buffer_nilfs_volatile(path[level].bp_bh)) {
+ ret = nilfs_btree_prepare_update_v(btree, path, level, dat);
+ if (ret < 0)
+ return ret;
+ }
+ while ((++level < nilfs_btree_height(btree) - 1) &&
+ !buffer_dirty(path[level].bp_bh)) {
+
+ WARN_ON(buffer_nilfs_volatile(path[level].bp_bh));
+ ret = nilfs_btree_prepare_update_v(btree, path, level, dat);
+ if (ret < 0)
+ goto out;
+ }
+
+ /* success */
+ *maxlevelp = level - 1;
+ return 0;
+
+ /* error */
+ out:
+ while (--level > minlevel)
+ nilfs_btree_abort_update_v(btree, path, level, dat);
+ if (!buffer_nilfs_volatile(path[level].bp_bh))
+ nilfs_btree_abort_update_v(btree, path, level, dat);
+ return ret;
+}
+
+static void nilfs_btree_commit_propagate_v(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int minlevel, int maxlevel,
+ struct buffer_head *bh,
+ struct inode *dat)
+{
+ int level;
+
+ if (!buffer_nilfs_volatile(path[minlevel].bp_bh))
+ nilfs_btree_commit_update_v(btree, path, minlevel, dat);
+
+ for (level = minlevel + 1; level <= maxlevel; level++)
+ nilfs_btree_commit_update_v(btree, path, level, dat);
+}
+
+static int nilfs_btree_propagate_v(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int level, struct buffer_head *bh)
+{
+ int maxlevel = 0, ret;
+ struct nilfs_btree_node *parent;
+ struct inode *dat = nilfs_bmap_get_dat(btree);
+ __u64 ptr;
+ int ncmax;
+
+ get_bh(bh);
+ path[level].bp_bh = bh;
+ ret = nilfs_btree_prepare_propagate_v(btree, path, level, &maxlevel,
+ dat);
+ if (ret < 0)
+ goto out;
+
+ if (buffer_nilfs_volatile(path[level].bp_bh)) {
+ parent = nilfs_btree_get_node(btree, path, level + 1, &ncmax);
+ ptr = nilfs_btree_node_get_ptr(parent,
+ path[level + 1].bp_index,
+ ncmax);
+ ret = nilfs_dat_mark_dirty(dat, ptr);
+ if (ret < 0)
+ goto out;
+ }
+
+ nilfs_btree_commit_propagate_v(btree, path, level, maxlevel, bh, dat);
+
+ out:
+ brelse(path[level].bp_bh);
+ path[level].bp_bh = NULL;
+ return ret;
+}
+
+static int nilfs_btree_propagate(struct nilfs_bmap *btree,
+ struct buffer_head *bh)
+{
+ struct nilfs_btree_path *path;
+ struct nilfs_btree_node *node;
+ __u64 key;
+ int level, ret;
+
+ WARN_ON(!buffer_dirty(bh));
+
+ path = nilfs_btree_alloc_path();
+ if (path == NULL)
+ return -ENOMEM;
+
+ if (buffer_nilfs_node(bh)) {
+ node = (struct nilfs_btree_node *)bh->b_data;
+ key = nilfs_btree_node_get_key(node, 0);
+ level = nilfs_btree_node_get_level(node);
+ } else {
+ key = nilfs_bmap_data_get_key(btree, bh);
+ level = NILFS_BTREE_LEVEL_DATA;
+ }
+
+ ret = nilfs_btree_do_lookup(btree, path, key, NULL, level + 1, 0);
+ if (ret < 0) {
+ if (unlikely(ret == -ENOENT))
+ printk(KERN_CRIT "%s: key = %llu, level == %d\n",
+ __func__, (unsigned long long)key, level);
+ goto out;
+ }
+
+ ret = NILFS_BMAP_USE_VBN(btree) ?
+ nilfs_btree_propagate_v(btree, path, level, bh) :
+ nilfs_btree_propagate_p(btree, path, level, bh);
+
+ out:
+ nilfs_btree_free_path(path);
+
+ return ret;
+}
+
+static int nilfs_btree_propagate_gc(struct nilfs_bmap *btree,
+ struct buffer_head *bh)
+{
+ return nilfs_dat_mark_dirty(nilfs_bmap_get_dat(btree), bh->b_blocknr);
+}
+
+static void nilfs_btree_add_dirty_buffer(struct nilfs_bmap *btree,
+ struct list_head *lists,
+ struct buffer_head *bh)
+{
+ struct list_head *head;
+ struct buffer_head *cbh;
+ struct nilfs_btree_node *node, *cnode;
+ __u64 key, ckey;
+ int level;
+
+ get_bh(bh);
+ node = (struct nilfs_btree_node *)bh->b_data;
+ key = nilfs_btree_node_get_key(node, 0);
+ level = nilfs_btree_node_get_level(node);
+ if (level < NILFS_BTREE_LEVEL_NODE_MIN ||
+ level >= NILFS_BTREE_LEVEL_MAX) {
+ dump_stack();
+ printk(KERN_WARNING
+ "%s: invalid btree level: %d (key=%llu, ino=%lu, "
+ "blocknr=%llu)\n",
+ __func__, level, (unsigned long long)key,
+ NILFS_BMAP_I(btree)->vfs_inode.i_ino,
+ (unsigned long long)bh->b_blocknr);
+ return;
+ }
+
+ list_for_each(head, &lists[level]) {
+ cbh = list_entry(head, struct buffer_head, b_assoc_buffers);
+ cnode = (struct nilfs_btree_node *)cbh->b_data;
+ ckey = nilfs_btree_node_get_key(cnode, 0);
+ if (key < ckey)
+ break;
+ }
+ list_add_tail(&bh->b_assoc_buffers, head);
+}
+
+static void nilfs_btree_lookup_dirty_buffers(struct nilfs_bmap *btree,
+ struct list_head *listp)
+{
+ struct address_space *btcache = &NILFS_BMAP_I(btree)->i_btnode_cache;
+ struct list_head lists[NILFS_BTREE_LEVEL_MAX];
+ struct pagevec pvec;
+ struct buffer_head *bh, *head;
+ pgoff_t index = 0;
+ int level, i;
+
+ for (level = NILFS_BTREE_LEVEL_NODE_MIN;
+ level < NILFS_BTREE_LEVEL_MAX;
+ level++)
+ INIT_LIST_HEAD(&lists[level]);
+
+ pagevec_init(&pvec, 0);
+
+ while (pagevec_lookup_tag(&pvec, btcache, &index, PAGECACHE_TAG_DIRTY,
+ PAGEVEC_SIZE)) {
+ for (i = 0; i < pagevec_count(&pvec); i++) {
+ bh = head = page_buffers(pvec.pages[i]);
+ do {
+ if (buffer_dirty(bh))
+ nilfs_btree_add_dirty_buffer(btree,
+ lists, bh);
+ } while ((bh = bh->b_this_page) != head);
+ }
+ pagevec_release(&pvec);
+ cond_resched();
+ }
+
+ for (level = NILFS_BTREE_LEVEL_NODE_MIN;
+ level < NILFS_BTREE_LEVEL_MAX;
+ level++)
+ list_splice_tail(&lists[level], listp);
+}
+
+static int nilfs_btree_assign_p(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int level,
+ struct buffer_head **bh,
+ sector_t blocknr,
+ union nilfs_binfo *binfo)
+{
+ struct nilfs_btree_node *parent;
+ __u64 key;
+ __u64 ptr;
+ int ncmax, ret;
+
+ parent = nilfs_btree_get_node(btree, path, level + 1, &ncmax);
+ ptr = nilfs_btree_node_get_ptr(parent, path[level + 1].bp_index,
+ ncmax);
+ if (buffer_nilfs_node(*bh)) {
+ path[level].bp_ctxt.oldkey = ptr;
+ path[level].bp_ctxt.newkey = blocknr;
+ path[level].bp_ctxt.bh = *bh;
+ ret = nilfs_btnode_prepare_change_key(
+ &NILFS_BMAP_I(btree)->i_btnode_cache,
+ &path[level].bp_ctxt);
+ if (ret < 0)
+ return ret;
+ nilfs_btnode_commit_change_key(
+ &NILFS_BMAP_I(btree)->i_btnode_cache,
+ &path[level].bp_ctxt);
+ *bh = path[level].bp_ctxt.bh;
+ }
+
+ nilfs_btree_node_set_ptr(parent, path[level + 1].bp_index, blocknr,
+ ncmax);
+
+ key = nilfs_btree_node_get_key(parent, path[level + 1].bp_index);
+ /* on-disk format */
+ binfo->bi_dat.bi_blkoff = cpu_to_le64(key);
+ binfo->bi_dat.bi_level = level;
+
+ return 0;
+}
+
+static int nilfs_btree_assign_v(struct nilfs_bmap *btree,
+ struct nilfs_btree_path *path,
+ int level,
+ struct buffer_head **bh,
+ sector_t blocknr,
+ union nilfs_binfo *binfo)
+{
+ struct nilfs_btree_node *parent;
+ struct inode *dat = nilfs_bmap_get_dat(btree);
+ __u64 key;
+ __u64 ptr;
+ union nilfs_bmap_ptr_req req;
+ int ncmax, ret;
+
+ parent = nilfs_btree_get_node(btree, path, level + 1, &ncmax);
+ ptr = nilfs_btree_node_get_ptr(parent, path[level + 1].bp_index,
+ ncmax);
+ req.bpr_ptr = ptr;
+ ret = nilfs_dat_prepare_start(dat, &req.bpr_req);
+ if (ret < 0)
+ return ret;
+ nilfs_dat_commit_start(dat, &req.bpr_req, blocknr);
+
+ key = nilfs_btree_node_get_key(parent, path[level + 1].bp_index);
+ /* on-disk format */
+ binfo->bi_v.bi_vblocknr = cpu_to_le64(ptr);
+ binfo->bi_v.bi_blkoff = cpu_to_le64(key);
+
+ return 0;
+}
+
+static int nilfs_btree_assign(struct nilfs_bmap *btree,
+ struct buffer_head **bh,
+ sector_t blocknr,
+ union nilfs_binfo *binfo)
+{
+ struct nilfs_btree_path *path;
+ struct nilfs_btree_node *node;
+ __u64 key;
+ int level, ret;
+
+ path = nilfs_btree_alloc_path();
+ if (path == NULL)
+ return -ENOMEM;
+
+ if (buffer_nilfs_node(*bh)) {
+ node = (struct nilfs_btree_node *)(*bh)->b_data;
+ key = nilfs_btree_node_get_key(node, 0);
+ level = nilfs_btree_node_get_level(node);
+ } else {
+ key = nilfs_bmap_data_get_key(btree, *bh);
+ level = NILFS_BTREE_LEVEL_DATA;
+ }
+
+ ret = nilfs_btree_do_lookup(btree, path, key, NULL, level + 1, 0);
+ if (ret < 0) {
+ WARN_ON(ret == -ENOENT);
+ goto out;
+ }
+
+ ret = NILFS_BMAP_USE_VBN(btree) ?
+ nilfs_btree_assign_v(btree, path, level, bh, blocknr, binfo) :
+ nilfs_btree_assign_p(btree, path, level, bh, blocknr, binfo);
+
+ out:
+ nilfs_btree_free_path(path);
+
+ return ret;
+}
+
+static int nilfs_btree_assign_gc(struct nilfs_bmap *btree,
+ struct buffer_head **bh,
+ sector_t blocknr,
+ union nilfs_binfo *binfo)
+{
+ struct nilfs_btree_node *node;
+ __u64 key;
+ int ret;
+
+ ret = nilfs_dat_move(nilfs_bmap_get_dat(btree), (*bh)->b_blocknr,
+ blocknr);
+ if (ret < 0)
+ return ret;
+
+ if (buffer_nilfs_node(*bh)) {
+ node = (struct nilfs_btree_node *)(*bh)->b_data;
+ key = nilfs_btree_node_get_key(node, 0);
+ } else
+ key = nilfs_bmap_data_get_key(btree, *bh);
+
+ /* on-disk format */
+ binfo->bi_v.bi_vblocknr = cpu_to_le64((*bh)->b_blocknr);
+ binfo->bi_v.bi_blkoff = cpu_to_le64(key);
+
+ return 0;
+}
+
+static int nilfs_btree_mark(struct nilfs_bmap *btree, __u64 key, int level)
+{
+ struct buffer_head *bh;
+ struct nilfs_btree_path *path;
+ __u64 ptr;
+ int ret;
+
+ path = nilfs_btree_alloc_path();
+ if (path == NULL)
+ return -ENOMEM;
+
+ ret = nilfs_btree_do_lookup(btree, path, key, &ptr, level + 1, 0);
+ if (ret < 0) {
+ WARN_ON(ret == -ENOENT);
+ goto out;
+ }
+ ret = nilfs_btree_get_block(btree, ptr, &bh);
+ if (ret < 0) {
+ WARN_ON(ret == -ENOENT);
+ goto out;
+ }
+
+ if (!buffer_dirty(bh))
+ mark_buffer_dirty(bh);
+ brelse(bh);
+ if (!nilfs_bmap_dirty(btree))
+ nilfs_bmap_set_dirty(btree);
+
+ out:
+ nilfs_btree_free_path(path);
+ return ret;
+}
+
+static const struct nilfs_bmap_operations nilfs_btree_ops = {
+ .bop_lookup = nilfs_btree_lookup,
+ .bop_lookup_contig = nilfs_btree_lookup_contig,
+ .bop_insert = nilfs_btree_insert,
+ .bop_delete = nilfs_btree_delete,
+ .bop_clear = NULL,
+
+ .bop_propagate = nilfs_btree_propagate,
+
+ .bop_lookup_dirty_buffers = nilfs_btree_lookup_dirty_buffers,
+
+ .bop_assign = nilfs_btree_assign,
+ .bop_mark = nilfs_btree_mark,
+
+ .bop_seek_key = nilfs_btree_seek_key,
+ .bop_last_key = nilfs_btree_last_key,
+
+ .bop_check_insert = NULL,
+ .bop_check_delete = nilfs_btree_check_delete,
+ .bop_gather_data = nilfs_btree_gather_data,
+};
+
+static const struct nilfs_bmap_operations nilfs_btree_ops_gc = {
+ .bop_lookup = NULL,
+ .bop_lookup_contig = NULL,
+ .bop_insert = NULL,
+ .bop_delete = NULL,
+ .bop_clear = NULL,
+
+ .bop_propagate = nilfs_btree_propagate_gc,
+
+ .bop_lookup_dirty_buffers = nilfs_btree_lookup_dirty_buffers,
+
+ .bop_assign = nilfs_btree_assign_gc,
+ .bop_mark = NULL,
+
+ .bop_seek_key = NULL,
+ .bop_last_key = NULL,
+
+ .bop_check_insert = NULL,
+ .bop_check_delete = NULL,
+ .bop_gather_data = NULL,
+};
+
+static void __nilfs_btree_init(struct nilfs_bmap *bmap)
+{
+ bmap->b_ops = &nilfs_btree_ops;
+ bmap->b_nchildren_per_block =
+ NILFS_BTREE_NODE_NCHILDREN_MAX(nilfs_btree_node_size(bmap));
+}
+
+int nilfs_btree_init(struct nilfs_bmap *bmap)
+{
+ int ret = 0;
+
+ __nilfs_btree_init(bmap);
+
+ if (nilfs_btree_root_broken(nilfs_btree_get_root(bmap),
+ bmap->b_inode->i_ino))
+ ret = -EIO;
+ return ret;
+}
+
+void nilfs_btree_init_gc(struct nilfs_bmap *bmap)
+{
+ bmap->b_ops = &nilfs_btree_ops_gc;
+ bmap->b_nchildren_per_block =
+ NILFS_BTREE_NODE_NCHILDREN_MAX(nilfs_btree_node_size(bmap));
+}