nilfs2: B-tree based block mapping
This adds declarations and functions of NILFS2 B-tree.
Two variants are integrated in the NILFS2 B-tree. The B-tree for the most
files points to the child nodes or data blocks with virtual block
addresses, whereas the B-tree of the DAT uses actual block addresses.
Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/nilfs2/btree.c b/fs/nilfs2/btree.c
new file mode 100644
index 0000000..893f019
--- /dev/null
+++ b/fs/nilfs2/btree.c
@@ -0,0 +1,2276 @@
+/*
+ * 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"
+
+/**
+ * struct nilfs_btree_path - A path on which B-tree operations are executed
+ * @bp_bh: buffer head of node block
+ * @bp_sib_bh: buffer head of sibling node block
+ * @bp_index: index of child node
+ * @bp_oldreq: ptr end request for old ptr
+ * @bp_newreq: ptr alloc request for new ptr
+ * @bp_op: rebalance operation
+ */
+struct nilfs_btree_path {
+ struct buffer_head *bp_bh;
+ struct buffer_head *bp_sib_bh;
+ int bp_index;
+ union nilfs_bmap_ptr_req bp_oldreq;
+ union nilfs_bmap_ptr_req bp_newreq;
+ struct nilfs_btnode_chkey_ctxt bp_ctxt;
+ void (*bp_op)(struct nilfs_btree *, struct nilfs_btree_path *,
+ int, __u64 *, __u64 *);
+};
+
+/*
+ * B-tree path operations
+ */
+
+static struct kmem_cache *nilfs_btree_path_cache;
+
+int __init nilfs_btree_path_cache_init(void)
+{
+ nilfs_btree_path_cache =
+ kmem_cache_create("nilfs2_btree_path_cache",
+ sizeof(struct nilfs_btree_path) *
+ NILFS_BTREE_LEVEL_MAX, 0, 0, NULL);
+ return (nilfs_btree_path_cache != NULL) ? 0 : -ENOMEM;
+}
+
+void nilfs_btree_path_cache_destroy(void)
+{
+ kmem_cache_destroy(nilfs_btree_path_cache);
+}
+
+static inline struct nilfs_btree_path *
+nilfs_btree_alloc_path(const struct nilfs_btree *btree)
+{
+ return (struct nilfs_btree_path *)
+ kmem_cache_alloc(nilfs_btree_path_cache, GFP_NOFS);
+}
+
+static inline void nilfs_btree_free_path(const struct nilfs_btree *btree,
+ struct nilfs_btree_path *path)
+{
+ kmem_cache_free(nilfs_btree_path_cache, path);
+}
+
+static void nilfs_btree_init_path(const struct nilfs_btree *btree,
+ struct nilfs_btree_path *path)
+{
+ int level;
+
+ for (level = NILFS_BTREE_LEVEL_DATA;
+ 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;
+ }
+}
+
+static void nilfs_btree_clear_path(const struct nilfs_btree *btree,
+ struct nilfs_btree_path *path)
+{
+ int level;
+
+ for (level = NILFS_BTREE_LEVEL_DATA;
+ level < NILFS_BTREE_LEVEL_MAX;
+ level++) {
+ if (path[level].bp_bh != NULL) {
+ nilfs_bmap_put_block(&btree->bt_bmap,
+ path[level].bp_bh);
+ path[level].bp_bh = NULL;
+ }
+ /* sib_bh is released or deleted by prepare or commit
+ * operations. */
+ 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;
+ }
+}
+
+
+/*
+ * B-tree node operations
+ */
+
+static inline int
+nilfs_btree_node_get_flags(const struct nilfs_btree *btree,
+ const struct nilfs_btree_node *node)
+{
+ return node->bn_flags;
+}
+
+static inline void
+nilfs_btree_node_set_flags(struct nilfs_btree *btree,
+ struct nilfs_btree_node *node,
+ int flags)
+{
+ node->bn_flags = flags;
+}
+
+static inline int nilfs_btree_node_root(const struct nilfs_btree *btree,
+ const struct nilfs_btree_node *node)
+{
+ return nilfs_btree_node_get_flags(btree, node) & NILFS_BTREE_NODE_ROOT;
+}
+
+static inline int
+nilfs_btree_node_get_level(const struct nilfs_btree *btree,
+ const struct nilfs_btree_node *node)
+{
+ return node->bn_level;
+}
+
+static inline void
+nilfs_btree_node_set_level(struct nilfs_btree *btree,
+ struct nilfs_btree_node *node,
+ int level)
+{
+ node->bn_level = level;
+}
+
+static inline int
+nilfs_btree_node_get_nchildren(const struct nilfs_btree *btree,
+ const struct nilfs_btree_node *node)
+{
+ return le16_to_cpu(node->bn_nchildren);
+}
+
+static inline void
+nilfs_btree_node_set_nchildren(struct nilfs_btree *btree,
+ struct nilfs_btree_node *node,
+ int nchildren)
+{
+ node->bn_nchildren = cpu_to_le16(nchildren);
+}
+
+static inline int
+nilfs_btree_node_size(const struct nilfs_btree *btree)
+{
+ return 1 << btree->bt_bmap.b_inode->i_blkbits;
+}
+
+static inline int
+nilfs_btree_node_nchildren_min(const struct nilfs_btree *btree,
+ const struct nilfs_btree_node *node)
+{
+ return nilfs_btree_node_root(btree, node) ?
+ NILFS_BTREE_ROOT_NCHILDREN_MIN :
+ NILFS_BTREE_NODE_NCHILDREN_MIN(nilfs_btree_node_size(btree));
+}
+
+static inline int
+nilfs_btree_node_nchildren_max(const struct nilfs_btree *btree,
+ const struct nilfs_btree_node *node)
+{
+ return nilfs_btree_node_root(btree, node) ?
+ NILFS_BTREE_ROOT_NCHILDREN_MAX :
+ NILFS_BTREE_NODE_NCHILDREN_MAX(nilfs_btree_node_size(btree));
+}
+
+static inline __le64 *
+nilfs_btree_node_dkeys(const struct nilfs_btree *btree,
+ const struct nilfs_btree_node *node)
+{
+ return (__le64 *)((char *)(node + 1) +
+ (nilfs_btree_node_root(btree, node) ?
+ 0 : NILFS_BTREE_NODE_EXTRA_PAD_SIZE));
+}
+
+static inline __le64 *
+nilfs_btree_node_dptrs(const struct nilfs_btree *btree,
+ const struct nilfs_btree_node *node)
+{
+ return (__le64 *)(nilfs_btree_node_dkeys(btree, node) +
+ nilfs_btree_node_nchildren_max(btree, node));
+}
+
+static inline __u64
+nilfs_btree_node_get_key(const struct nilfs_btree *btree,
+ const struct nilfs_btree_node *node, int index)
+{
+ return nilfs_bmap_dkey_to_key(*(nilfs_btree_node_dkeys(btree, node) +
+ index));
+}
+
+static inline void
+nilfs_btree_node_set_key(struct nilfs_btree *btree,
+ struct nilfs_btree_node *node, int index, __u64 key)
+{
+ *(nilfs_btree_node_dkeys(btree, node) + index) =
+ nilfs_bmap_key_to_dkey(key);
+}
+
+static inline __u64
+nilfs_btree_node_get_ptr(const struct nilfs_btree *btree,
+ const struct nilfs_btree_node *node,
+ int index)
+{
+ return nilfs_bmap_dptr_to_ptr(*(nilfs_btree_node_dptrs(btree, node) +
+ index));
+}
+
+static inline void
+nilfs_btree_node_set_ptr(struct nilfs_btree *btree,
+ struct nilfs_btree_node *node,
+ int index,
+ __u64 ptr)
+{
+ *(nilfs_btree_node_dptrs(btree, node) + index) =
+ nilfs_bmap_ptr_to_dptr(ptr);
+}
+
+static void nilfs_btree_node_init(struct nilfs_btree *btree,
+ struct nilfs_btree_node *node,
+ int flags, int level, int nchildren,
+ const __u64 *keys, const __u64 *ptrs)
+{
+ __le64 *dkeys;
+ __le64 *dptrs;
+ int i;
+
+ nilfs_btree_node_set_flags(btree, node, flags);
+ nilfs_btree_node_set_level(btree, node, level);
+ nilfs_btree_node_set_nchildren(btree, node, nchildren);
+
+ dkeys = nilfs_btree_node_dkeys(btree, node);
+ dptrs = nilfs_btree_node_dptrs(btree, node);
+ for (i = 0; i < nchildren; i++) {
+ dkeys[i] = nilfs_bmap_key_to_dkey(keys[i]);
+ dptrs[i] = nilfs_bmap_ptr_to_dptr(ptrs[i]);
+ }
+}
+
+/* Assume the buffer heads corresponding to left and right are locked. */
+static void nilfs_btree_node_move_left(struct nilfs_btree *btree,
+ struct nilfs_btree_node *left,
+ struct nilfs_btree_node *right,
+ int n)
+{
+ __le64 *ldkeys, *rdkeys;
+ __le64 *ldptrs, *rdptrs;
+ int lnchildren, rnchildren;
+
+ ldkeys = nilfs_btree_node_dkeys(btree, left);
+ ldptrs = nilfs_btree_node_dptrs(btree, left);
+ lnchildren = nilfs_btree_node_get_nchildren(btree, left);
+
+ rdkeys = nilfs_btree_node_dkeys(btree, right);
+ rdptrs = nilfs_btree_node_dptrs(btree, right);
+ rnchildren = nilfs_btree_node_get_nchildren(btree, 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(btree, left, lnchildren);
+ nilfs_btree_node_set_nchildren(btree, right, rnchildren);
+}
+
+/* Assume that the buffer heads corresponding to left and right are locked. */
+static void nilfs_btree_node_move_right(struct nilfs_btree *btree,
+ struct nilfs_btree_node *left,
+ struct nilfs_btree_node *right,
+ int n)
+{
+ __le64 *ldkeys, *rdkeys;
+ __le64 *ldptrs, *rdptrs;
+ int lnchildren, rnchildren;
+
+ ldkeys = nilfs_btree_node_dkeys(btree, left);
+ ldptrs = nilfs_btree_node_dptrs(btree, left);
+ lnchildren = nilfs_btree_node_get_nchildren(btree, left);
+
+ rdkeys = nilfs_btree_node_dkeys(btree, right);
+ rdptrs = nilfs_btree_node_dptrs(btree, right);
+ rnchildren = nilfs_btree_node_get_nchildren(btree, 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(btree, left, lnchildren);
+ nilfs_btree_node_set_nchildren(btree, right, rnchildren);
+}
+
+/* Assume that the buffer head corresponding to node is locked. */
+static void nilfs_btree_node_insert(struct nilfs_btree *btree,
+ struct nilfs_btree_node *node,
+ __u64 key, __u64 ptr, int index)
+{
+ __le64 *dkeys;
+ __le64 *dptrs;
+ int nchildren;
+
+ dkeys = nilfs_btree_node_dkeys(btree, node);
+ dptrs = nilfs_btree_node_dptrs(btree, node);
+ nchildren = nilfs_btree_node_get_nchildren(btree, 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] = nilfs_bmap_key_to_dkey(key);
+ dptrs[index] = nilfs_bmap_ptr_to_dptr(ptr);
+ nchildren++;
+ nilfs_btree_node_set_nchildren(btree, node, nchildren);
+}
+
+/* Assume that the buffer head corresponding to node is locked. */
+static void nilfs_btree_node_delete(struct nilfs_btree *btree,
+ struct nilfs_btree_node *node,
+ __u64 *keyp, __u64 *ptrp, int index)
+{
+ __u64 key;
+ __u64 ptr;
+ __le64 *dkeys;
+ __le64 *dptrs;
+ int nchildren;
+
+ dkeys = nilfs_btree_node_dkeys(btree, node);
+ dptrs = nilfs_btree_node_dptrs(btree, node);
+ key = nilfs_bmap_dkey_to_key(dkeys[index]);
+ ptr = nilfs_bmap_dptr_to_ptr(dptrs[index]);
+ nchildren = nilfs_btree_node_get_nchildren(btree, 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(btree, node, nchildren);
+}
+
+static int nilfs_btree_node_lookup(const struct nilfs_btree *btree,
+ 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(btree, node) - 1;
+ index = 0;
+ s = 0;
+ while (low <= high) {
+ index = (low + high) / 2;
+ nkey = nilfs_btree_node_get_key(btree, 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(btree, node) >
+ NILFS_BTREE_LEVEL_NODE_MIN) {
+ if ((s > 0) && (index > 0))
+ index--;
+ } else if (s < 0)
+ index++;
+
+ out:
+ BUG_ON(indexp == NULL);
+ *indexp = index;
+
+ return s == 0;
+}
+
+static inline struct nilfs_btree_node *
+nilfs_btree_get_root(const struct nilfs_btree *btree)
+{
+ return (struct nilfs_btree_node *)btree->bt_bmap.b_u.u_data;
+}
+
+static inline struct nilfs_btree_node *
+nilfs_btree_get_nonroot_node(const struct nilfs_btree *btree,
+ const struct nilfs_btree_path *path,
+ int level)
+{
+ return (struct nilfs_btree_node *)path[level].bp_bh->b_data;
+}
+
+static inline struct nilfs_btree_node *
+nilfs_btree_get_sib_node(const struct nilfs_btree *btree,
+ const struct nilfs_btree_path *path,
+ int level)
+{
+ return (struct nilfs_btree_node *)path[level].bp_sib_bh->b_data;
+}
+
+static inline int nilfs_btree_height(const struct nilfs_btree *btree)
+{
+ return nilfs_btree_node_get_level(btree, nilfs_btree_get_root(btree))
+ + 1;
+}
+
+static inline struct nilfs_btree_node *
+nilfs_btree_get_node(const struct nilfs_btree *btree,
+ const struct nilfs_btree_path *path,
+ int level)
+{
+ return (level == nilfs_btree_height(btree) - 1) ?
+ nilfs_btree_get_root(btree) :
+ nilfs_btree_get_nonroot_node(btree, path, level);
+}
+
+static int nilfs_btree_do_lookup(const struct nilfs_btree *btree,
+ struct nilfs_btree_path *path,
+ __u64 key, __u64 *ptrp, int minlevel)
+{
+ struct nilfs_btree_node *node;
+ __u64 ptr;
+ int level, index, found, ret;
+
+ BUG_ON(minlevel <= NILFS_BTREE_LEVEL_DATA);
+
+ node = nilfs_btree_get_root(btree);
+ level = nilfs_btree_node_get_level(btree, node);
+ if ((level < minlevel) ||
+ (nilfs_btree_node_get_nchildren(btree, node) <= 0))
+ return -ENOENT;
+
+ found = nilfs_btree_node_lookup(btree, node, key, &index);
+ ptr = nilfs_btree_node_get_ptr(btree, node, index);
+ path[level].bp_bh = NULL;
+ path[level].bp_index = index;
+
+ for (level--; level >= minlevel; level--) {
+ ret = nilfs_bmap_get_block(&btree->bt_bmap, ptr,
+ &path[level].bp_bh);
+ if (ret < 0)
+ return ret;
+ node = nilfs_btree_get_nonroot_node(btree, path, level);
+ BUG_ON(level != nilfs_btree_node_get_level(btree, node));
+ if (!found)
+ found = nilfs_btree_node_lookup(btree, node, key,
+ &index);
+ else
+ index = 0;
+ if (index < nilfs_btree_node_nchildren_max(btree, node))
+ ptr = nilfs_btree_node_get_ptr(btree, node, index);
+ else {
+ BUG_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_btree *btree,
+ struct nilfs_btree_path *path,
+ __u64 *keyp, __u64 *ptrp)
+{
+ struct nilfs_btree_node *node;
+ __u64 ptr;
+ int index, level, ret;
+
+ node = nilfs_btree_get_root(btree);
+ index = nilfs_btree_node_get_nchildren(btree, node) - 1;
+ if (index < 0)
+ return -ENOENT;
+ level = nilfs_btree_node_get_level(btree, node);
+ ptr = nilfs_btree_node_get_ptr(btree, node, index);
+ path[level].bp_bh = NULL;
+ path[level].bp_index = index;
+
+ for (level--; level > 0; level--) {
+ ret = nilfs_bmap_get_block(&btree->bt_bmap, ptr,
+ &path[level].bp_bh);
+ if (ret < 0)
+ return ret;
+ node = nilfs_btree_get_nonroot_node(btree, path, level);
+ BUG_ON(level != nilfs_btree_node_get_level(btree, node));
+ index = nilfs_btree_node_get_nchildren(btree, node) - 1;
+ ptr = nilfs_btree_node_get_ptr(btree, node, index);
+ path[level].bp_index = index;
+ }
+
+ if (keyp != NULL)
+ *keyp = nilfs_btree_node_get_key(btree, node, index);
+ if (ptrp != NULL)
+ *ptrp = ptr;
+
+ return 0;
+}
+
+static int nilfs_btree_lookup(const struct nilfs_bmap *bmap,
+ __u64 key, int level, __u64 *ptrp)
+{
+ struct nilfs_btree *btree;
+ struct nilfs_btree_path *path;
+ __u64 ptr;
+ int ret;
+
+ btree = (struct nilfs_btree *)bmap;
+ path = nilfs_btree_alloc_path(btree);
+ if (path == NULL)
+ return -ENOMEM;
+ nilfs_btree_init_path(btree, path);
+
+ ret = nilfs_btree_do_lookup(btree, path, key, &ptr, level);
+
+ if (ptrp != NULL)
+ *ptrp = ptr;
+
+ nilfs_btree_clear_path(btree, path);
+ nilfs_btree_free_path(btree, path);
+
+ return ret;
+}
+
+static void nilfs_btree_promote_key(struct nilfs_btree *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 key)
+{
+ if (level < nilfs_btree_height(btree) - 1) {
+ do {
+ lock_buffer(path[level].bp_bh);
+ nilfs_btree_node_set_key(
+ btree,
+ nilfs_btree_get_nonroot_node(
+ btree, path, level),
+ path[level].bp_index, key);
+ if (!buffer_dirty(path[level].bp_bh))
+ nilfs_btnode_mark_dirty(path[level].bp_bh);
+ unlock_buffer(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(btree,
+ nilfs_btree_get_root(btree),
+ path[level].bp_index, key);
+ }
+}
+
+static void nilfs_btree_do_insert(struct nilfs_btree *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 *keyp, __u64 *ptrp)
+{
+ struct nilfs_btree_node *node;
+
+ if (level < nilfs_btree_height(btree) - 1) {
+ lock_buffer(path[level].bp_bh);
+ node = nilfs_btree_get_nonroot_node(btree, path, level);
+ nilfs_btree_node_insert(btree, node, *keyp, *ptrp,
+ path[level].bp_index);
+ if (!buffer_dirty(path[level].bp_bh))
+ nilfs_btnode_mark_dirty(path[level].bp_bh);
+ unlock_buffer(path[level].bp_bh);
+
+ if (path[level].bp_index == 0)
+ nilfs_btree_promote_key(btree, path, level + 1,
+ nilfs_btree_node_get_key(
+ btree, node, 0));
+ } else {
+ node = nilfs_btree_get_root(btree);
+ nilfs_btree_node_insert(btree, node, *keyp, *ptrp,
+ path[level].bp_index);
+ }
+}
+
+static void nilfs_btree_carry_left(struct nilfs_btree *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 *keyp, __u64 *ptrp)
+{
+ struct nilfs_btree_node *node, *left;
+ int nchildren, lnchildren, n, move;
+
+ lock_buffer(path[level].bp_bh);
+ lock_buffer(path[level].bp_sib_bh);
+
+ node = nilfs_btree_get_nonroot_node(btree, path, level);
+ left = nilfs_btree_get_sib_node(btree, path, level);
+ nchildren = nilfs_btree_node_get_nchildren(btree, node);
+ lnchildren = nilfs_btree_node_get_nchildren(btree, left);
+ 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(btree, left, node, n);
+
+ if (!buffer_dirty(path[level].bp_bh))
+ nilfs_btnode_mark_dirty(path[level].bp_bh);
+ if (!buffer_dirty(path[level].bp_sib_bh))
+ nilfs_btnode_mark_dirty(path[level].bp_sib_bh);
+
+ unlock_buffer(path[level].bp_bh);
+ unlock_buffer(path[level].bp_sib_bh);
+
+ nilfs_btree_promote_key(btree, path, level + 1,
+ nilfs_btree_node_get_key(btree, node, 0));
+
+ if (move) {
+ nilfs_bmap_put_block(&btree->bt_bmap, 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 {
+ nilfs_bmap_put_block(&btree->bt_bmap, 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_btree *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 *keyp, __u64 *ptrp)
+{
+ struct nilfs_btree_node *node, *right;
+ int nchildren, rnchildren, n, move;
+
+ lock_buffer(path[level].bp_bh);
+ lock_buffer(path[level].bp_sib_bh);
+
+ node = nilfs_btree_get_nonroot_node(btree, path, level);
+ right = nilfs_btree_get_sib_node(btree, path, level);
+ nchildren = nilfs_btree_node_get_nchildren(btree, node);
+ rnchildren = nilfs_btree_node_get_nchildren(btree, right);
+ 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(btree, node, right, n);
+
+ if (!buffer_dirty(path[level].bp_bh))
+ nilfs_btnode_mark_dirty(path[level].bp_bh);
+ if (!buffer_dirty(path[level].bp_sib_bh))
+ nilfs_btnode_mark_dirty(path[level].bp_sib_bh);
+
+ unlock_buffer(path[level].bp_bh);
+ unlock_buffer(path[level].bp_sib_bh);
+
+ path[level + 1].bp_index++;
+ nilfs_btree_promote_key(btree, path, level + 1,
+ nilfs_btree_node_get_key(btree, right, 0));
+ path[level + 1].bp_index--;
+
+ if (move) {
+ nilfs_bmap_put_block(&btree->bt_bmap, 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(btree, node);
+ path[level + 1].bp_index++;
+ } else {
+ nilfs_bmap_put_block(&btree->bt_bmap, 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_btree *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;
+
+ lock_buffer(path[level].bp_bh);
+ lock_buffer(path[level].bp_sib_bh);
+
+ node = nilfs_btree_get_nonroot_node(btree, path, level);
+ right = nilfs_btree_get_sib_node(btree, path, level);
+ nchildren = nilfs_btree_node_get_nchildren(btree, node);
+ move = 0;
+
+ n = (nchildren + 1) / 2;
+ if (n > nchildren - path[level].bp_index) {
+ n--;
+ move = 1;
+ }
+
+ nilfs_btree_node_move_right(btree, node, right, n);
+
+ if (!buffer_dirty(path[level].bp_bh))
+ nilfs_btnode_mark_dirty(path[level].bp_bh);
+ if (!buffer_dirty(path[level].bp_sib_bh))
+ nilfs_btnode_mark_dirty(path[level].bp_sib_bh);
+
+ unlock_buffer(path[level].bp_bh);
+ unlock_buffer(path[level].bp_sib_bh);
+
+ newkey = nilfs_btree_node_get_key(btree, right, 0);
+ newptr = path[level].bp_newreq.bpr_ptr;
+
+ if (move) {
+ path[level].bp_index -=
+ nilfs_btree_node_get_nchildren(btree, node);
+ nilfs_btree_node_insert(btree, right, *keyp, *ptrp,
+ path[level].bp_index);
+
+ *keyp = nilfs_btree_node_get_key(btree, right, 0);
+ *ptrp = path[level].bp_newreq.bpr_ptr;
+
+ nilfs_bmap_put_block(&btree->bt_bmap, 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(btree, right, 0);
+ *ptrp = path[level].bp_newreq.bpr_ptr;
+
+ nilfs_bmap_put_block(&btree->bt_bmap, path[level].bp_sib_bh);
+ path[level].bp_sib_bh = NULL;
+ }
+
+ path[level + 1].bp_index++;
+}
+
+static void nilfs_btree_grow(struct nilfs_btree *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 *keyp, __u64 *ptrp)
+{
+ struct nilfs_btree_node *root, *child;
+ int n;
+
+ lock_buffer(path[level].bp_sib_bh);
+
+ root = nilfs_btree_get_root(btree);
+ child = nilfs_btree_get_sib_node(btree, path, level);
+
+ n = nilfs_btree_node_get_nchildren(btree, root);
+
+ nilfs_btree_node_move_right(btree, root, child, n);
+ nilfs_btree_node_set_level(btree, root, level + 1);
+
+ if (!buffer_dirty(path[level].bp_sib_bh))
+ nilfs_btnode_mark_dirty(path[level].bp_sib_bh);
+
+ unlock_buffer(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(btree, child, 0);
+ *ptrp = path[level].bp_newreq.bpr_ptr;
+}
+
+static __u64 nilfs_btree_find_near(const struct nilfs_btree *btree,
+ const struct nilfs_btree_path *path)
+{
+ struct nilfs_btree_node *node;
+ int level;
+
+ 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);
+ return nilfs_btree_node_get_ptr(btree, node,
+ path[level].bp_index - 1);
+ }
+
+ /* parent */
+ level = NILFS_BTREE_LEVEL_NODE_MIN + 1;
+ if (level <= nilfs_btree_height(btree) - 1) {
+ node = nilfs_btree_get_node(btree, path, level);
+ return nilfs_btree_node_get_ptr(btree, node,
+ path[level].bp_index);
+ }
+
+ return NILFS_BMAP_INVALID_PTR;
+}
+
+static __u64 nilfs_btree_find_target_v(const struct nilfs_btree *btree,
+ const struct nilfs_btree_path *path,
+ __u64 key)
+{
+ __u64 ptr;
+
+ ptr = nilfs_bmap_find_target_seq(&btree->bt_bmap, 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->bt_bmap);
+}
+
+static void nilfs_btree_set_target_v(struct nilfs_btree *btree, __u64 key,
+ __u64 ptr)
+{
+ btree->bt_bmap.b_last_allocated_key = key;
+ btree->bt_bmap.b_last_allocated_ptr = ptr;
+}
+
+static int nilfs_btree_prepare_insert(struct nilfs_btree *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, ret;
+
+ stats->bs_nblocks = 0;
+ level = NILFS_BTREE_LEVEL_DATA;
+
+ /* allocate a new ptr for data block */
+ if (btree->bt_ops->btop_find_target != NULL)
+ path[level].bp_newreq.bpr_ptr =
+ (*btree->bt_ops->btop_find_target)(btree, path, key);
+
+ ret = (*btree->bt_bmap.b_pops->bpop_prepare_alloc_ptr)(
+ &btree->bt_bmap, &path[level].bp_newreq);
+ if (ret < 0)
+ goto err_out_data;
+
+ for (level = NILFS_BTREE_LEVEL_NODE_MIN;
+ level < nilfs_btree_height(btree) - 1;
+ level++) {
+ node = nilfs_btree_get_nonroot_node(btree, path, level);
+ if (nilfs_btree_node_get_nchildren(btree, node) <
+ nilfs_btree_node_nchildren_max(btree, node)) {
+ path[level].bp_op = nilfs_btree_do_insert;
+ stats->bs_nblocks++;
+ goto out;
+ }
+
+ parent = nilfs_btree_get_node(btree, path, level + 1);
+ pindex = path[level + 1].bp_index;
+
+ /* left sibling */
+ if (pindex > 0) {
+ sibptr = nilfs_btree_node_get_ptr(btree, parent,
+ pindex - 1);
+ ret = nilfs_bmap_get_block(&btree->bt_bmap, sibptr,
+ &bh);
+ if (ret < 0)
+ goto err_out_child_node;
+ sib = (struct nilfs_btree_node *)bh->b_data;
+ if (nilfs_btree_node_get_nchildren(btree, sib) <
+ nilfs_btree_node_nchildren_max(btree, sib)) {
+ path[level].bp_sib_bh = bh;
+ path[level].bp_op = nilfs_btree_carry_left;
+ stats->bs_nblocks++;
+ goto out;
+ } else
+ nilfs_bmap_put_block(&btree->bt_bmap, bh);
+ }
+
+ /* right sibling */
+ if (pindex <
+ nilfs_btree_node_get_nchildren(btree, parent) - 1) {
+ sibptr = nilfs_btree_node_get_ptr(btree, parent,
+ pindex + 1);
+ ret = nilfs_bmap_get_block(&btree->bt_bmap, sibptr,
+ &bh);
+ if (ret < 0)
+ goto err_out_child_node;
+ sib = (struct nilfs_btree_node *)bh->b_data;
+ if (nilfs_btree_node_get_nchildren(btree, sib) <
+ nilfs_btree_node_nchildren_max(btree, sib)) {
+ path[level].bp_sib_bh = bh;
+ path[level].bp_op = nilfs_btree_carry_right;
+ stats->bs_nblocks++;
+ goto out;
+ } else
+ nilfs_bmap_put_block(&btree->bt_bmap, bh);
+ }
+
+ /* split */
+ path[level].bp_newreq.bpr_ptr =
+ path[level - 1].bp_newreq.bpr_ptr + 1;
+ ret = (*btree->bt_bmap.b_pops->bpop_prepare_alloc_ptr)(
+ &btree->bt_bmap, &path[level].bp_newreq);
+ if (ret < 0)
+ goto err_out_child_node;
+ ret = nilfs_bmap_get_new_block(&btree->bt_bmap,
+ path[level].bp_newreq.bpr_ptr,
+ &bh);
+ if (ret < 0)
+ goto err_out_curr_node;
+
+ stats->bs_nblocks++;
+
+ lock_buffer(bh);
+ nilfs_btree_node_init(btree,
+ (struct nilfs_btree_node *)bh->b_data,
+ 0, level, 0, NULL, NULL);
+ unlock_buffer(bh);
+ 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(btree, node) <
+ nilfs_btree_node_nchildren_max(btree, node)) {
+ 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 = (*btree->bt_bmap.b_pops->bpop_prepare_alloc_ptr)(
+ &btree->bt_bmap, &path[level].bp_newreq);
+ if (ret < 0)
+ goto err_out_child_node;
+ ret = nilfs_bmap_get_new_block(&btree->bt_bmap,
+ path[level].bp_newreq.bpr_ptr, &bh);
+ if (ret < 0)
+ goto err_out_curr_node;
+
+ lock_buffer(bh);
+ nilfs_btree_node_init(btree, (struct nilfs_btree_node *)bh->b_data,
+ 0, level, 0, NULL, NULL);
+ unlock_buffer(bh);
+ 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:
+ (*btree->bt_bmap.b_pops->bpop_abort_alloc_ptr)(&btree->bt_bmap,
+ &path[level].bp_newreq);
+ err_out_child_node:
+ for (level--; level > NILFS_BTREE_LEVEL_DATA; level--) {
+ nilfs_bmap_delete_block(&btree->bt_bmap, path[level].bp_sib_bh);
+ (*btree->bt_bmap.b_pops->bpop_abort_alloc_ptr)(
+ &btree->bt_bmap, &path[level].bp_newreq);
+
+ }
+
+ (*btree->bt_bmap.b_pops->bpop_abort_alloc_ptr)(&btree->bt_bmap,
+ &path[level].bp_newreq);
+ err_out_data:
+ *levelp = level;
+ stats->bs_nblocks = 0;
+ return ret;
+}
+
+static void nilfs_btree_commit_insert(struct nilfs_btree *btree,
+ struct nilfs_btree_path *path,
+ int maxlevel, __u64 key, __u64 ptr)
+{
+ int level;
+
+ set_buffer_nilfs_volatile((struct buffer_head *)((unsigned long)ptr));
+ ptr = path[NILFS_BTREE_LEVEL_DATA].bp_newreq.bpr_ptr;
+ if (btree->bt_ops->btop_set_target != NULL)
+ (*btree->bt_ops->btop_set_target)(btree, key, ptr);
+
+ for (level = NILFS_BTREE_LEVEL_NODE_MIN; level <= maxlevel; level++) {
+ if (btree->bt_bmap.b_pops->bpop_commit_alloc_ptr != NULL) {
+ (*btree->bt_bmap.b_pops->bpop_commit_alloc_ptr)(
+ &btree->bt_bmap, &path[level - 1].bp_newreq);
+ }
+ (*path[level].bp_op)(btree, path, level, &key, &ptr);
+ }
+
+ if (!nilfs_bmap_dirty(&btree->bt_bmap))
+ nilfs_bmap_set_dirty(&btree->bt_bmap);
+}
+
+static int nilfs_btree_insert(struct nilfs_bmap *bmap, __u64 key, __u64 ptr)
+{
+ struct nilfs_btree *btree;
+ struct nilfs_btree_path *path;
+ struct nilfs_bmap_stats stats;
+ int level, ret;
+
+ btree = (struct nilfs_btree *)bmap;
+ path = nilfs_btree_alloc_path(btree);
+ if (path == NULL)
+ return -ENOMEM;
+ nilfs_btree_init_path(btree, path);
+
+ ret = nilfs_btree_do_lookup(btree, path, key, NULL,
+ NILFS_BTREE_LEVEL_NODE_MIN);
+ 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_bmap_add_blocks(bmap, stats.bs_nblocks);
+
+ out:
+ nilfs_btree_clear_path(btree, path);
+ nilfs_btree_free_path(btree, path);
+ return ret;
+}
+
+static void nilfs_btree_do_delete(struct nilfs_btree *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 *keyp, __u64 *ptrp)
+{
+ struct nilfs_btree_node *node;
+
+ if (level < nilfs_btree_height(btree) - 1) {
+ lock_buffer(path[level].bp_bh);
+ node = nilfs_btree_get_nonroot_node(btree, path, level);
+ nilfs_btree_node_delete(btree, node, keyp, ptrp,
+ path[level].bp_index);
+ if (!buffer_dirty(path[level].bp_bh))
+ nilfs_btnode_mark_dirty(path[level].bp_bh);
+ unlock_buffer(path[level].bp_bh);
+ if (path[level].bp_index == 0)
+ nilfs_btree_promote_key(btree, path, level + 1,
+ nilfs_btree_node_get_key(btree, node, 0));
+ } else {
+ node = nilfs_btree_get_root(btree);
+ nilfs_btree_node_delete(btree, node, keyp, ptrp,
+ path[level].bp_index);
+ }
+}
+
+static void nilfs_btree_borrow_left(struct nilfs_btree *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 *keyp, __u64 *ptrp)
+{
+ struct nilfs_btree_node *node, *left;
+ int nchildren, lnchildren, n;
+
+ nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
+
+ lock_buffer(path[level].bp_bh);
+ lock_buffer(path[level].bp_sib_bh);
+
+ node = nilfs_btree_get_nonroot_node(btree, path, level);
+ left = nilfs_btree_get_sib_node(btree, path, level);
+ nchildren = nilfs_btree_node_get_nchildren(btree, node);
+ lnchildren = nilfs_btree_node_get_nchildren(btree, left);
+
+ n = (nchildren + lnchildren) / 2 - nchildren;
+
+ nilfs_btree_node_move_right(btree, left, node, n);
+
+ if (!buffer_dirty(path[level].bp_bh))
+ nilfs_btnode_mark_dirty(path[level].bp_bh);
+ if (!buffer_dirty(path[level].bp_sib_bh))
+ nilfs_btnode_mark_dirty(path[level].bp_sib_bh);
+
+ unlock_buffer(path[level].bp_bh);
+ unlock_buffer(path[level].bp_sib_bh);
+
+ nilfs_btree_promote_key(btree, path, level + 1,
+ nilfs_btree_node_get_key(btree, node, 0));
+
+ nilfs_bmap_put_block(&btree->bt_bmap, path[level].bp_sib_bh);
+ path[level].bp_sib_bh = NULL;
+ path[level].bp_index += n;
+}
+
+static void nilfs_btree_borrow_right(struct nilfs_btree *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 *keyp, __u64 *ptrp)
+{
+ struct nilfs_btree_node *node, *right;
+ int nchildren, rnchildren, n;
+
+ nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
+
+ lock_buffer(path[level].bp_bh);
+ lock_buffer(path[level].bp_sib_bh);
+
+ node = nilfs_btree_get_nonroot_node(btree, path, level);
+ right = nilfs_btree_get_sib_node(btree, path, level);
+ nchildren = nilfs_btree_node_get_nchildren(btree, node);
+ rnchildren = nilfs_btree_node_get_nchildren(btree, right);
+
+ n = (nchildren + rnchildren) / 2 - nchildren;
+
+ nilfs_btree_node_move_left(btree, node, right, n);
+
+ if (!buffer_dirty(path[level].bp_bh))
+ nilfs_btnode_mark_dirty(path[level].bp_bh);
+ if (!buffer_dirty(path[level].bp_sib_bh))
+ nilfs_btnode_mark_dirty(path[level].bp_sib_bh);
+
+ unlock_buffer(path[level].bp_bh);
+ unlock_buffer(path[level].bp_sib_bh);
+
+ path[level + 1].bp_index++;
+ nilfs_btree_promote_key(btree, path, level + 1,
+ nilfs_btree_node_get_key(btree, right, 0));
+ path[level + 1].bp_index--;
+
+ nilfs_bmap_put_block(&btree->bt_bmap, path[level].bp_sib_bh);
+ path[level].bp_sib_bh = NULL;
+}
+
+static void nilfs_btree_concat_left(struct nilfs_btree *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 *keyp, __u64 *ptrp)
+{
+ struct nilfs_btree_node *node, *left;
+ int n;
+
+ nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
+
+ lock_buffer(path[level].bp_bh);
+ lock_buffer(path[level].bp_sib_bh);
+
+ node = nilfs_btree_get_nonroot_node(btree, path, level);
+ left = nilfs_btree_get_sib_node(btree, path, level);
+
+ n = nilfs_btree_node_get_nchildren(btree, node);
+
+ nilfs_btree_node_move_left(btree, left, node, n);
+
+ if (!buffer_dirty(path[level].bp_sib_bh))
+ nilfs_btnode_mark_dirty(path[level].bp_sib_bh);
+
+ unlock_buffer(path[level].bp_bh);
+ unlock_buffer(path[level].bp_sib_bh);
+
+ nilfs_bmap_delete_block(&btree->bt_bmap, 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(btree, left);
+}
+
+static void nilfs_btree_concat_right(struct nilfs_btree *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 *keyp, __u64 *ptrp)
+{
+ struct nilfs_btree_node *node, *right;
+ int n;
+
+ nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
+
+ lock_buffer(path[level].bp_bh);
+ lock_buffer(path[level].bp_sib_bh);
+
+ node = nilfs_btree_get_nonroot_node(btree, path, level);
+ right = nilfs_btree_get_sib_node(btree, path, level);
+
+ n = nilfs_btree_node_get_nchildren(btree, right);
+
+ nilfs_btree_node_move_left(btree, node, right, n);
+
+ if (!buffer_dirty(path[level].bp_bh))
+ nilfs_btnode_mark_dirty(path[level].bp_bh);
+
+ unlock_buffer(path[level].bp_bh);
+ unlock_buffer(path[level].bp_sib_bh);
+
+ nilfs_bmap_delete_block(&btree->bt_bmap, path[level].bp_sib_bh);
+ path[level].bp_sib_bh = NULL;
+ path[level + 1].bp_index++;
+}
+
+static void nilfs_btree_shrink(struct nilfs_btree *btree,
+ struct nilfs_btree_path *path,
+ int level, __u64 *keyp, __u64 *ptrp)
+{
+ struct nilfs_btree_node *root, *child;
+ int n;
+
+ nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
+
+ lock_buffer(path[level].bp_bh);
+ root = nilfs_btree_get_root(btree);
+ child = nilfs_btree_get_nonroot_node(btree, path, level);
+
+ nilfs_btree_node_delete(btree, root, NULL, NULL, 0);
+ nilfs_btree_node_set_level(btree, root, level);
+ n = nilfs_btree_node_get_nchildren(btree, child);
+ nilfs_btree_node_move_left(btree, root, child, n);
+ unlock_buffer(path[level].bp_bh);
+
+ nilfs_bmap_delete_block(&btree->bt_bmap, path[level].bp_bh);
+ path[level].bp_bh = NULL;
+}
+
+
+static int nilfs_btree_prepare_delete(struct nilfs_btree *btree,
+ struct nilfs_btree_path *path,
+ int *levelp,
+ struct nilfs_bmap_stats *stats)
+{
+ struct buffer_head *bh;
+ struct nilfs_btree_node *node, *parent, *sib;
+ __u64 sibptr;
+ int pindex, level, ret;
+
+ ret = 0;
+ stats->bs_nblocks = 0;
+ for (level = NILFS_BTREE_LEVEL_NODE_MIN;
+ level < nilfs_btree_height(btree) - 1;
+ level++) {
+ node = nilfs_btree_get_nonroot_node(btree, path, level);
+ path[level].bp_oldreq.bpr_ptr =
+ nilfs_btree_node_get_ptr(btree, node,
+ path[level].bp_index);
+ if (btree->bt_bmap.b_pops->bpop_prepare_end_ptr != NULL) {
+ ret = (*btree->bt_bmap.b_pops->bpop_prepare_end_ptr)(
+ &btree->bt_bmap, &path[level].bp_oldreq);
+ if (ret < 0)
+ goto err_out_child_node;
+ }
+
+ if (nilfs_btree_node_get_nchildren(btree, node) >
+ nilfs_btree_node_nchildren_min(btree, node)) {
+ path[level].bp_op = nilfs_btree_do_delete;
+ stats->bs_nblocks++;
+ goto out;
+ }
+
+ parent = nilfs_btree_get_node(btree, path, level + 1);
+ pindex = path[level + 1].bp_index;
+
+ if (pindex > 0) {
+ /* left sibling */
+ sibptr = nilfs_btree_node_get_ptr(btree, parent,
+ pindex - 1);
+ ret = nilfs_bmap_get_block(&btree->bt_bmap, sibptr,
+ &bh);
+ if (ret < 0)
+ goto err_out_curr_node;
+ sib = (struct nilfs_btree_node *)bh->b_data;
+ if (nilfs_btree_node_get_nchildren(btree, sib) >
+ nilfs_btree_node_nchildren_min(btree, sib)) {
+ 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(btree, parent) - 1) {
+ /* right sibling */
+ sibptr = nilfs_btree_node_get_ptr(btree, parent,
+ pindex + 1);
+ ret = nilfs_bmap_get_block(&btree->bt_bmap, sibptr,
+ &bh);
+ if (ret < 0)
+ goto err_out_curr_node;
+ sib = (struct nilfs_btree_node *)bh->b_data;
+ if (nilfs_btree_node_get_nchildren(btree, sib) >
+ nilfs_btree_node_nchildren_min(btree, sib)) {
+ 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++;
+ /* continue; */
+ }
+ } else {
+ /* no siblings */
+ /* the only child of the root node */
+ BUG_ON(level != nilfs_btree_height(btree) - 2);
+ if (nilfs_btree_node_get_nchildren(btree, node) - 1 <=
+ NILFS_BTREE_ROOT_NCHILDREN_MAX) {
+ path[level].bp_op = nilfs_btree_shrink;
+ stats->bs_nblocks += 2;
+ } else {
+ path[level].bp_op = nilfs_btree_do_delete;
+ stats->bs_nblocks++;
+ }
+
+ goto out;
+
+ }
+ }
+
+ node = nilfs_btree_get_root(btree);
+ path[level].bp_oldreq.bpr_ptr =
+ nilfs_btree_node_get_ptr(btree, node, path[level].bp_index);
+ if (btree->bt_bmap.b_pops->bpop_prepare_end_ptr != NULL) {
+ ret = (*btree->bt_bmap.b_pops->bpop_prepare_end_ptr)(
+ &btree->bt_bmap, &path[level].bp_oldreq);
+ if (ret < 0)
+ goto err_out_child_node;
+ }
+ /* child of the root node is deleted */
+ path[level].bp_op = nilfs_btree_do_delete;
+ stats->bs_nblocks++;
+
+ /* success */
+ out:
+ *levelp = level;
+ return ret;
+
+ /* error */
+ err_out_curr_node:
+ if (btree->bt_bmap.b_pops->bpop_abort_end_ptr != NULL)
+ (*btree->bt_bmap.b_pops->bpop_abort_end_ptr)(
+ &btree->bt_bmap, &path[level].bp_oldreq);
+ err_out_child_node:
+ for (level--; level >= NILFS_BTREE_LEVEL_NODE_MIN; level--) {
+ nilfs_bmap_put_block(&btree->bt_bmap, path[level].bp_sib_bh);
+ if (btree->bt_bmap.b_pops->bpop_abort_end_ptr != NULL)
+ (*btree->bt_bmap.b_pops->bpop_abort_end_ptr)(
+ &btree->bt_bmap, &path[level].bp_oldreq);
+ }
+ *levelp = level;
+ stats->bs_nblocks = 0;
+ return ret;
+}
+
+static void nilfs_btree_commit_delete(struct nilfs_btree *btree,
+ struct nilfs_btree_path *path,
+ int maxlevel)
+{
+ int level;
+
+ for (level = NILFS_BTREE_LEVEL_NODE_MIN; level <= maxlevel; level++) {
+ if (btree->bt_bmap.b_pops->bpop_commit_end_ptr != NULL)
+ (*btree->bt_bmap.b_pops->bpop_commit_end_ptr)(
+ &btree->bt_bmap, &path[level].bp_oldreq);
+ (*path[level].bp_op)(btree, path, level, NULL, NULL);
+ }
+
+ if (!nilfs_bmap_dirty(&btree->bt_bmap))
+ nilfs_bmap_set_dirty(&btree->bt_bmap);
+}
+
+static int nilfs_btree_delete(struct nilfs_bmap *bmap, __u64 key)
+
+{
+ struct nilfs_btree *btree;
+ struct nilfs_btree_path *path;
+ struct nilfs_bmap_stats stats;
+ int level, ret;
+
+ btree = (struct nilfs_btree *)bmap;
+ path = nilfs_btree_alloc_path(btree);
+ if (path == NULL)
+ return -ENOMEM;
+ nilfs_btree_init_path(btree, path);
+ ret = nilfs_btree_do_lookup(btree, path, key, NULL,
+ NILFS_BTREE_LEVEL_NODE_MIN);
+ if (ret < 0)
+ goto out;
+
+ ret = nilfs_btree_prepare_delete(btree, path, &level, &stats);
+ if (ret < 0)
+ goto out;
+ nilfs_btree_commit_delete(btree, path, level);
+ nilfs_bmap_sub_blocks(bmap, stats.bs_nblocks);
+
+out:
+ nilfs_btree_clear_path(btree, path);
+ nilfs_btree_free_path(btree, path);
+ return ret;
+}
+
+static int nilfs_btree_last_key(const struct nilfs_bmap *bmap, __u64 *keyp)
+{
+ struct nilfs_btree *btree;
+ struct nilfs_btree_path *path;
+ int ret;
+
+ btree = (struct nilfs_btree *)bmap;
+ path = nilfs_btree_alloc_path(btree);
+ if (path == NULL)
+ return -ENOMEM;
+ nilfs_btree_init_path(btree, path);
+
+ ret = nilfs_btree_do_lookup_last(btree, path, keyp, NULL);
+
+ nilfs_btree_clear_path(btree, path);
+ nilfs_btree_free_path(btree, path);
+
+ return ret;
+}
+
+static int nilfs_btree_check_delete(struct nilfs_bmap *bmap, __u64 key)
+{
+ struct buffer_head *bh;
+ struct nilfs_btree *btree;
+ struct nilfs_btree_node *root, *node;
+ __u64 maxkey, nextmaxkey;
+ __u64 ptr;
+ int nchildren, ret;
+
+ btree = (struct nilfs_btree *)bmap;
+ 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(btree, root);
+ if (nchildren > 1)
+ return 0;
+ ptr = nilfs_btree_node_get_ptr(btree, root, nchildren - 1);
+ ret = nilfs_bmap_get_block(bmap, 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(btree, node);
+ maxkey = nilfs_btree_node_get_key(btree, node, nchildren - 1);
+ nextmaxkey = (nchildren > 1) ?
+ nilfs_btree_node_get_key(btree, node, nchildren - 2) : 0;
+ if (bh != NULL)
+ nilfs_bmap_put_block(bmap, bh);
+
+ return (maxkey == key) && (nextmaxkey < bmap->b_low);
+}
+
+static int nilfs_btree_gather_data(struct nilfs_bmap *bmap,
+ __u64 *keys, __u64 *ptrs, int nitems)
+{
+ struct buffer_head *bh;
+ struct nilfs_btree *btree;
+ struct nilfs_btree_node *node, *root;
+ __le64 *dkeys;
+ __le64 *dptrs;
+ __u64 ptr;
+ int nchildren, i, ret;
+
+ btree = (struct nilfs_btree *)bmap;
+ 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(btree, root);
+ BUG_ON(nchildren > 1);
+ ptr = nilfs_btree_node_get_ptr(btree, root, nchildren - 1);
+ ret = nilfs_bmap_get_block(bmap, ptr, &bh);
+ if (ret < 0)
+ return ret;
+ node = (struct nilfs_btree_node *)bh->b_data;
+ break;
+ default:
+ node = NULL;
+ BUG();
+ }
+
+ nchildren = nilfs_btree_node_get_nchildren(btree, node);
+ if (nchildren < nitems)
+ nitems = nchildren;
+ dkeys = nilfs_btree_node_dkeys(btree, node);
+ dptrs = nilfs_btree_node_dptrs(btree, node);
+ for (i = 0; i < nitems; i++) {
+ keys[i] = nilfs_bmap_dkey_to_key(dkeys[i]);
+ ptrs[i] = nilfs_bmap_dptr_to_ptr(dptrs[i]);
+ }
+
+ if (bh != NULL)
+ nilfs_bmap_put_block(bmap, bh);
+
+ return nitems;
+}
+
+static int
+nilfs_btree_prepare_convert_and_insert(struct nilfs_bmap *bmap, __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 nilfs_btree *btree;
+ int ret;
+
+ btree = (struct nilfs_btree *)bmap;
+ stats->bs_nblocks = 0;
+
+ /* for data */
+ /* cannot find near ptr */
+ if (btree->bt_ops->btop_find_target != NULL)
+ dreq->bpr_ptr
+ = (*btree->bt_ops->btop_find_target)(btree, NULL, key);
+ ret = (*bmap->b_pops->bpop_prepare_alloc_ptr)(bmap, dreq);
+ if (ret < 0)
+ return ret;
+
+ *bhp = NULL;
+ stats->bs_nblocks++;
+ if (nreq != NULL) {
+ nreq->bpr_ptr = dreq->bpr_ptr + 1;
+ ret = (*bmap->b_pops->bpop_prepare_alloc_ptr)(bmap, nreq);
+ if (ret < 0)
+ goto err_out_dreq;
+
+ ret = nilfs_bmap_get_new_block(bmap, nreq->bpr_ptr, &bh);
+ if (ret < 0)
+ goto err_out_nreq;
+
+ *bhp = bh;
+ stats->bs_nblocks++;
+ }
+
+ /* success */
+ return 0;
+
+ /* error */
+ err_out_nreq:
+ (*bmap->b_pops->bpop_abort_alloc_ptr)(bmap, nreq);
+ err_out_dreq:
+ (*bmap->b_pops->bpop_abort_alloc_ptr)(bmap, dreq);
+ stats->bs_nblocks = 0;
+ return ret;
+
+}
+
+static void
+nilfs_btree_commit_convert_and_insert(struct nilfs_bmap *bmap,
+ __u64 key, __u64 ptr,
+ const __u64 *keys, const __u64 *ptrs,
+ int n, __u64 low, __u64 high,
+ union nilfs_bmap_ptr_req *dreq,
+ union nilfs_bmap_ptr_req *nreq,
+ struct buffer_head *bh)
+{
+ struct nilfs_btree *btree;
+ struct nilfs_btree_node *node;
+ __u64 tmpptr;
+
+ /* free resources */
+ if (bmap->b_ops->bop_clear != NULL)
+ (*bmap->b_ops->bop_clear)(bmap);
+
+ /* ptr must be a pointer to a buffer head. */
+ set_buffer_nilfs_volatile((struct buffer_head *)((unsigned long)ptr));
+
+ /* convert and insert */
+ btree = (struct nilfs_btree *)bmap;
+ nilfs_btree_init(bmap, low, high);
+ if (nreq != NULL) {
+ if (bmap->b_pops->bpop_commit_alloc_ptr != NULL) {
+ (*bmap->b_pops->bpop_commit_alloc_ptr)(bmap, dreq);
+ (*bmap->b_pops->bpop_commit_alloc_ptr)(bmap, nreq);
+ }
+
+ /* create child node at level 1 */
+ lock_buffer(bh);
+ node = (struct nilfs_btree_node *)bh->b_data;
+ nilfs_btree_node_init(btree, node, 0, 1, n, keys, ptrs);
+ nilfs_btree_node_insert(btree, node,
+ key, dreq->bpr_ptr, n);
+ if (!buffer_dirty(bh))
+ nilfs_btnode_mark_dirty(bh);
+ if (!nilfs_bmap_dirty(bmap))
+ nilfs_bmap_set_dirty(bmap);
+
+ unlock_buffer(bh);
+ nilfs_bmap_put_block(bmap, bh);
+
+ /* create root node at level 2 */
+ node = nilfs_btree_get_root(btree);
+ tmpptr = nreq->bpr_ptr;
+ nilfs_btree_node_init(btree, node, NILFS_BTREE_NODE_ROOT,
+ 2, 1, &keys[0], &tmpptr);
+ } else {
+ if (bmap->b_pops->bpop_commit_alloc_ptr != NULL)
+ (*bmap->b_pops->bpop_commit_alloc_ptr)(bmap, dreq);
+
+ /* create root node at level 1 */
+ node = nilfs_btree_get_root(btree);
+ nilfs_btree_node_init(btree, node, NILFS_BTREE_NODE_ROOT,
+ 1, n, keys, ptrs);
+ nilfs_btree_node_insert(btree, node,
+ key, dreq->bpr_ptr, n);
+ if (!nilfs_bmap_dirty(bmap))
+ nilfs_bmap_set_dirty(bmap);
+ }
+
+ if (btree->bt_ops->btop_set_target != NULL)
+ (*btree->bt_ops->btop_set_target)(btree, key, dreq->bpr_ptr);
+}
+
+/**
+ * nilfs_btree_convert_and_insert -
+ * @bmap:
+ * @key:
+ * @ptr:
+ * @keys:
+ * @ptrs:
+ * @n:
+ * @low:
+ * @high:
+ */
+int nilfs_btree_convert_and_insert(struct nilfs_bmap *bmap,
+ __u64 key, __u64 ptr,
+ const __u64 *keys, const __u64 *ptrs,
+ int n, __u64 low, __u64 high)
+{
+ 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 << bmap->b_inode->i_blkbits)) {
+ di = &dreq;
+ ni = &nreq;
+ } else {
+ di = NULL;
+ ni = NULL;
+ BUG();
+ }
+
+ ret = nilfs_btree_prepare_convert_and_insert(bmap, key, di, ni, &bh,
+ &stats);
+ if (ret < 0)
+ return ret;
+ nilfs_btree_commit_convert_and_insert(bmap, key, ptr, keys, ptrs, n,
+ low, high, di, ni, bh);
+ nilfs_bmap_add_blocks(bmap, stats.bs_nblocks);
+ return 0;
+}
+
+static int nilfs_btree_propagate_p(struct nilfs_btree *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))
+ nilfs_btnode_mark_dirty(path[level].bp_bh);
+
+ return 0;
+}
+
+static int nilfs_btree_prepare_update_v(struct nilfs_btree *btree,
+ struct nilfs_btree_path *path,
+ int level)
+{
+ struct nilfs_btree_node *parent;
+ int ret;
+
+ parent = nilfs_btree_get_node(btree, path, level + 1);
+ path[level].bp_oldreq.bpr_ptr =
+ nilfs_btree_node_get_ptr(btree, parent,
+ path[level + 1].bp_index);
+ path[level].bp_newreq.bpr_ptr = path[level].bp_oldreq.bpr_ptr + 1;
+ ret = nilfs_bmap_prepare_update(&btree->bt_bmap,
+ &path[level].bp_oldreq,
+ &path[level].bp_newreq);
+ 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->bt_bmap)->i_btnode_cache,
+ &path[level].bp_ctxt);
+ if (ret < 0) {
+ nilfs_bmap_abort_update(&btree->bt_bmap,
+ &path[level].bp_oldreq,
+ &path[level].bp_newreq);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static void nilfs_btree_commit_update_v(struct nilfs_btree *btree,
+ struct nilfs_btree_path *path,
+ int level)
+{
+ struct nilfs_btree_node *parent;
+
+ nilfs_bmap_commit_update(&btree->bt_bmap,
+ &path[level].bp_oldreq,
+ &path[level].bp_newreq);
+
+ if (buffer_nilfs_node(path[level].bp_bh)) {
+ nilfs_btnode_commit_change_key(
+ &NILFS_BMAP_I(&btree->bt_bmap)->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);
+ nilfs_btree_node_set_ptr(btree, parent, path[level + 1].bp_index,
+ path[level].bp_newreq.bpr_ptr);
+}
+
+static void nilfs_btree_abort_update_v(struct nilfs_btree *btree,
+ struct nilfs_btree_path *path,
+ int level)
+{
+ nilfs_bmap_abort_update(&btree->bt_bmap,
+ &path[level].bp_oldreq,
+ &path[level].bp_newreq);
+ if (buffer_nilfs_node(path[level].bp_bh))
+ nilfs_btnode_abort_change_key(
+ &NILFS_BMAP_I(&btree->bt_bmap)->i_btnode_cache,
+ &path[level].bp_ctxt);
+}
+
+static int nilfs_btree_prepare_propagate_v(struct nilfs_btree *btree,
+ struct nilfs_btree_path *path,
+ int minlevel,
+ int *maxlevelp)
+{
+ int level, ret;
+
+ level = minlevel;
+ if (!buffer_nilfs_volatile(path[level].bp_bh)) {
+ ret = nilfs_btree_prepare_update_v(btree, path, level);
+ if (ret < 0)
+ return ret;
+ }
+ while ((++level < nilfs_btree_height(btree) - 1) &&
+ !buffer_dirty(path[level].bp_bh)) {
+
+ BUG_ON(buffer_nilfs_volatile(path[level].bp_bh));
+ ret = nilfs_btree_prepare_update_v(btree, path, level);
+ if (ret < 0)
+ goto out;
+ }
+
+ /* success */
+ BUG_ON(maxlevelp == NULL);
+ *maxlevelp = level - 1;
+ return 0;
+
+ /* error */
+ out:
+ while (--level > minlevel)
+ nilfs_btree_abort_update_v(btree, path, level);
+ if (!buffer_nilfs_volatile(path[level].bp_bh))
+ nilfs_btree_abort_update_v(btree, path, level);
+ return ret;
+}
+
+static void nilfs_btree_commit_propagate_v(struct nilfs_btree *btree,
+ struct nilfs_btree_path *path,
+ int minlevel,
+ int maxlevel,
+ struct buffer_head *bh)
+{
+ int level;
+
+ if (!buffer_nilfs_volatile(path[minlevel].bp_bh))
+ nilfs_btree_commit_update_v(btree, path, minlevel);
+
+ for (level = minlevel + 1; level <= maxlevel; level++)
+ nilfs_btree_commit_update_v(btree, path, level);
+}
+
+static int nilfs_btree_propagate_v(struct nilfs_btree *btree,
+ struct nilfs_btree_path *path,
+ int level,
+ struct buffer_head *bh)
+{
+ int maxlevel, ret;
+ struct nilfs_btree_node *parent;
+ __u64 ptr;
+
+ get_bh(bh);
+ path[level].bp_bh = bh;
+ ret = nilfs_btree_prepare_propagate_v(btree, path, level, &maxlevel);
+ if (ret < 0)
+ goto out;
+
+ if (buffer_nilfs_volatile(path[level].bp_bh)) {
+ parent = nilfs_btree_get_node(btree, path, level + 1);
+ ptr = nilfs_btree_node_get_ptr(btree, parent,
+ path[level + 1].bp_index);
+ ret = nilfs_bmap_mark_dirty(&btree->bt_bmap, ptr);
+ if (ret < 0)
+ goto out;
+ }
+
+ nilfs_btree_commit_propagate_v(btree, path, level, maxlevel, bh);
+
+ out:
+ brelse(path[level].bp_bh);
+ path[level].bp_bh = NULL;
+ return ret;
+}
+
+static int nilfs_btree_propagate(const struct nilfs_bmap *bmap,
+ struct buffer_head *bh)
+{
+ struct nilfs_btree *btree;
+ struct nilfs_btree_path *path;
+ struct nilfs_btree_node *node;
+ __u64 key;
+ int level, ret;
+
+ BUG_ON(!buffer_dirty(bh));
+
+ btree = (struct nilfs_btree *)bmap;
+ path = nilfs_btree_alloc_path(btree);
+ if (path == NULL)
+ return -ENOMEM;
+ nilfs_btree_init_path(btree, path);
+
+ if (buffer_nilfs_node(bh)) {
+ node = (struct nilfs_btree_node *)bh->b_data;
+ key = nilfs_btree_node_get_key(btree, node, 0);
+ level = nilfs_btree_node_get_level(btree, node);
+ } else {
+ key = nilfs_bmap_data_get_key(bmap, bh);
+ level = NILFS_BTREE_LEVEL_DATA;
+ }
+
+ ret = nilfs_btree_do_lookup(btree, path, key, NULL, level + 1);
+ if (ret < 0) {
+ /* BUG_ON(ret == -ENOENT); */
+ if (ret == -ENOENT) {
+ printk(KERN_CRIT "%s: key = %llu, level == %d\n",
+ __func__, (unsigned long long)key, level);
+ BUG();
+ }
+ goto out;
+ }
+
+ ret = (*btree->bt_ops->btop_propagate)(btree, path, level, bh);
+
+ out:
+ nilfs_btree_clear_path(btree, path);
+ nilfs_btree_free_path(btree, path);
+
+ return ret;
+}
+
+static int nilfs_btree_propagate_gc(const struct nilfs_bmap *bmap,
+ struct buffer_head *bh)
+{
+ return nilfs_bmap_mark_dirty(bmap, bh->b_blocknr);
+}
+
+static void nilfs_btree_add_dirty_buffer(struct nilfs_btree *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(btree, node, 0);
+ level = nilfs_btree_node_get_level(btree, node);
+ 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(btree, cnode, 0);
+ if (key < ckey)
+ break;
+ }
+ list_add_tail(&bh->b_assoc_buffers, head);
+}
+
+static void nilfs_btree_lookup_dirty_buffers(struct nilfs_bmap *bmap,
+ struct list_head *listp)
+{
+ struct nilfs_btree *btree = (struct nilfs_btree *)bmap;
+ struct address_space *btcache = &NILFS_BMAP_I(bmap)->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(&lists[level], listp->prev);
+}
+
+static int nilfs_btree_assign_p(struct nilfs_btree *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 ret;
+
+ parent = nilfs_btree_get_node(btree, path, level + 1);
+ ptr = nilfs_btree_node_get_ptr(btree, parent,
+ path[level + 1].bp_index);
+ 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->bt_bmap)->i_btnode_cache,
+ &path[level].bp_ctxt);
+ if (ret < 0)
+ return ret;
+ nilfs_btnode_commit_change_key(
+ &NILFS_BMAP_I(&btree->bt_bmap)->i_btnode_cache,
+ &path[level].bp_ctxt);
+ *bh = path[level].bp_ctxt.bh;
+ }
+
+ nilfs_btree_node_set_ptr(btree, parent,
+ path[level + 1].bp_index, blocknr);
+
+ key = nilfs_btree_node_get_key(btree, parent,
+ path[level + 1].bp_index);
+ /* on-disk format */
+ binfo->bi_dat.bi_blkoff = nilfs_bmap_key_to_dkey(key);
+ binfo->bi_dat.bi_level = level;
+
+ return 0;
+}
+
+static int nilfs_btree_assign_v(struct nilfs_btree *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;
+ union nilfs_bmap_ptr_req req;
+ int ret;
+
+ parent = nilfs_btree_get_node(btree, path, level + 1);
+ ptr = nilfs_btree_node_get_ptr(btree, parent,
+ path[level + 1].bp_index);
+ req.bpr_ptr = ptr;
+ ret = (*btree->bt_bmap.b_pops->bpop_prepare_start_ptr)(&btree->bt_bmap,
+ &req);
+ if (ret < 0)
+ return ret;
+ (*btree->bt_bmap.b_pops->bpop_commit_start_ptr)(&btree->bt_bmap,
+ &req, blocknr);
+
+ key = nilfs_btree_node_get_key(btree, parent,
+ path[level + 1].bp_index);
+ /* on-disk format */
+ 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_btree_assign(struct nilfs_bmap *bmap,
+ struct buffer_head **bh,
+ sector_t blocknr,
+ union nilfs_binfo *binfo)
+{
+ struct nilfs_btree *btree;
+ struct nilfs_btree_path *path;
+ struct nilfs_btree_node *node;
+ __u64 key;
+ int level, ret;
+
+ btree = (struct nilfs_btree *)bmap;
+ path = nilfs_btree_alloc_path(btree);
+ if (path == NULL)
+ return -ENOMEM;
+ nilfs_btree_init_path(btree, path);
+
+ if (buffer_nilfs_node(*bh)) {
+ node = (struct nilfs_btree_node *)(*bh)->b_data;
+ key = nilfs_btree_node_get_key(btree, node, 0);
+ level = nilfs_btree_node_get_level(btree, node);
+ } else {
+ key = nilfs_bmap_data_get_key(bmap, *bh);
+ level = NILFS_BTREE_LEVEL_DATA;
+ }
+
+ ret = nilfs_btree_do_lookup(btree, path, key, NULL, level + 1);
+ if (ret < 0) {
+ BUG_ON(ret == -ENOENT);
+ goto out;
+ }
+
+ ret = (*btree->bt_ops->btop_assign)(btree, path, level, bh,
+ blocknr, binfo);
+
+ out:
+ nilfs_btree_clear_path(btree, path);
+ nilfs_btree_free_path(btree, path);
+
+ return ret;
+}
+
+static int nilfs_btree_assign_gc(struct nilfs_bmap *bmap,
+ struct buffer_head **bh,
+ sector_t blocknr,
+ union nilfs_binfo *binfo)
+{
+ struct nilfs_btree *btree;
+ struct nilfs_btree_node *node;
+ __u64 key;
+ int ret;
+
+ btree = (struct nilfs_btree *)bmap;
+ ret = nilfs_bmap_move_v(bmap, (*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(btree, node, 0);
+ } else
+ key = nilfs_bmap_data_get_key(bmap, *bh);
+
+ /* on-disk format */
+ binfo->bi_v.bi_vblocknr = cpu_to_le64((*bh)->b_blocknr);
+ binfo->bi_v.bi_blkoff = nilfs_bmap_key_to_dkey(key);
+
+ return 0;
+}
+
+static int nilfs_btree_mark(struct nilfs_bmap *bmap, __u64 key, int level)
+{
+ struct buffer_head *bh;
+ struct nilfs_btree *btree;
+ struct nilfs_btree_path *path;
+ __u64 ptr;
+ int ret;
+
+ btree = (struct nilfs_btree *)bmap;
+ path = nilfs_btree_alloc_path(btree);
+ if (path == NULL)
+ return -ENOMEM;
+ nilfs_btree_init_path(btree, path);
+
+ ret = nilfs_btree_do_lookup(btree, path, key, &ptr, level + 1);
+ if (ret < 0) {
+ BUG_ON(ret == -ENOENT);
+ goto out;
+ }
+ ret = nilfs_bmap_get_block(&btree->bt_bmap, ptr, &bh);
+ if (ret < 0) {
+ BUG_ON(ret == -ENOENT);
+ goto out;
+ }
+
+ if (!buffer_dirty(bh))
+ nilfs_btnode_mark_dirty(bh);
+ nilfs_bmap_put_block(&btree->bt_bmap, bh);
+ if (!nilfs_bmap_dirty(&btree->bt_bmap))
+ nilfs_bmap_set_dirty(&btree->bt_bmap);
+
+ out:
+ nilfs_btree_clear_path(btree, path);
+ nilfs_btree_free_path(btree, path);
+ return ret;
+}
+
+static const struct nilfs_bmap_operations nilfs_btree_ops = {
+ .bop_lookup = nilfs_btree_lookup,
+ .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_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_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_last_key = NULL,
+ .bop_check_insert = NULL,
+ .bop_check_delete = NULL,
+ .bop_gather_data = NULL,
+};
+
+static const struct nilfs_btree_operations nilfs_btree_ops_v = {
+ .btop_find_target = nilfs_btree_find_target_v,
+ .btop_set_target = nilfs_btree_set_target_v,
+ .btop_propagate = nilfs_btree_propagate_v,
+ .btop_assign = nilfs_btree_assign_v,
+};
+
+static const struct nilfs_btree_operations nilfs_btree_ops_p = {
+ .btop_find_target = NULL,
+ .btop_set_target = NULL,
+ .btop_propagate = nilfs_btree_propagate_p,
+ .btop_assign = nilfs_btree_assign_p,
+};
+
+int nilfs_btree_init(struct nilfs_bmap *bmap, __u64 low, __u64 high)
+{
+ struct nilfs_btree *btree;
+
+ btree = (struct nilfs_btree *)bmap;
+ bmap->b_ops = &nilfs_btree_ops;
+ bmap->b_low = low;
+ bmap->b_high = high;
+ switch (bmap->b_inode->i_ino) {
+ case NILFS_DAT_INO:
+ btree->bt_ops = &nilfs_btree_ops_p;
+ break;
+ default:
+ btree->bt_ops = &nilfs_btree_ops_v;
+ break;
+ }
+
+ return 0;
+}
+
+void nilfs_btree_init_gc(struct nilfs_bmap *bmap)
+{
+ bmap->b_low = NILFS_BMAP_LARGE_LOW;
+ bmap->b_high = NILFS_BMAP_LARGE_HIGH;
+ bmap->b_ops = &nilfs_btree_ops_gc;
+}