/* * 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" /** * 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(void) { return kmem_cache_alloc(nilfs_btree_path_cache, GFP_NOFS); } static inline void nilfs_btree_free_path(struct nilfs_btree_path *path) { kmem_cache_free(nilfs_btree_path_cache, path); } static void nilfs_btree_init_path(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_release_path(struct nilfs_btree_path *path) { int level; for (level = NILFS_BTREE_LEVEL_DATA; level < NILFS_BTREE_LEVEL_MAX; level++) brelse(path[level].bp_bh); } /* * B-tree node operations */ static int nilfs_btree_get_block(const struct nilfs_btree *btree, __u64 ptr, struct buffer_head **bhp) { struct address_space *btnc = &NILFS_BMAP_I((struct nilfs_bmap *)btree)->i_btnode_cache; return nilfs_btnode_get(btnc, ptr, 0, bhp, 0); } static int nilfs_btree_get_new_block(const struct nilfs_btree *btree, __u64 ptr, struct buffer_head **bhp) { struct address_space *btnc = &NILFS_BMAP_I((struct nilfs_bmap *)btree)->i_btnode_cache; int ret; ret = nilfs_btnode_get(btnc, ptr, 0, bhp, 1); if (!ret) set_buffer_nilfs_volatile(*bhp); return ret; } static inline int nilfs_btree_node_get_flags(const struct nilfs_btree_node *node) { return node->bn_flags; } static inline void nilfs_btree_node_set_flags(struct nilfs_btree_node *node, int flags) { node->bn_flags = flags; } static inline int nilfs_btree_node_root(const struct nilfs_btree_node *node) { return nilfs_btree_node_get_flags(node) & NILFS_BTREE_NODE_ROOT; } static inline int nilfs_btree_node_get_level(const struct nilfs_btree_node *node) { return node->bn_level; } static inline void nilfs_btree_node_set_level(struct nilfs_btree_node *node, int level) { node->bn_level = level; } static inline int nilfs_btree_node_get_nchildren(const struct nilfs_btree_node *node) { return le16_to_cpu(node->bn_nchildren); } static inline void nilfs_btree_node_set_nchildren(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_node *node, const struct nilfs_btree *btree) { return nilfs_btree_node_root(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_node *node, const struct nilfs_btree *btree) { return nilfs_btree_node_root(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_node *node) { return (__le64 *)((char *)(node + 1) + (nilfs_btree_node_root(node) ? 0 : NILFS_BTREE_NODE_EXTRA_PAD_SIZE)); } static inline __le64 * nilfs_btree_node_dptrs(const struct nilfs_btree_node *node, const struct nilfs_btree *btree) { return (__le64 *)(nilfs_btree_node_dkeys(node) + nilfs_btree_node_nchildren_max(node, btree)); } static inline __u64 nilfs_btree_node_get_key(const struct nilfs_btree_node *node, int index) { return nilfs_bmap_dkey_to_key(*(nilfs_btree_node_dkeys(node) + index)); } static inline void nilfs_btree_node_set_key(struct nilfs_btree_node *node, int index, __u64 key) { *(nilfs_btree_node_dkeys(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(node, btree) + 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(node, btree) + 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(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, btree); 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(left); ldptrs = nilfs_btree_node_dptrs(left, btree); lnchildren = nilfs_btree_node_get_nchildren(left); rdkeys = nilfs_btree_node_dkeys(right); rdptrs = nilfs_btree_node_dptrs(right, btree); 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 *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(left); ldptrs = nilfs_btree_node_dptrs(left, btree); lnchildren = nilfs_btree_node_get_nchildren(left); rdkeys = nilfs_btree_node_dkeys(right); rdptrs = nilfs_btree_node_dptrs(right, btree); 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 *btree, struct nilfs_btree_node *node, __u64 key, __u64 ptr, int index) { __le64 *dkeys; __le64 *dptrs; int nchildren; dkeys = nilfs_btree_node_dkeys(node); dptrs = nilfs_btree_node_dptrs(node, btree); 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] = nilfs_bmap_key_to_dkey(key); dptrs[index] = nilfs_bmap_ptr_to_dptr(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 *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(node); dptrs = nilfs_btree_node_dptrs(node, btree); key = nilfs_bmap_dkey_to_key(dkeys[index]); ptr = nilfs_bmap_dptr_to_ptr(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; } 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_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_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(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(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; 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(btree, node, index); path[level].bp_bh = NULL; path[level].bp_index = index; for (level--; level >= minlevel; 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); BUG_ON(level != nilfs_btree_node_get_level(node)); if (!found) found = nilfs_btree_node_lookup(node, key, &index); else index = 0; if (index < nilfs_btree_node_nchildren_max(node, btree)) ptr = nilfs_btree_node_get_ptr(btree, node, index); 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_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(node) - 1; if (index < 0) return -ENOENT; level = nilfs_btree_node_get_level(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_btree_get_block(btree, ptr, &path[level].bp_bh); if (ret < 0) return ret; node = nilfs_btree_get_nonroot_node(path, level); BUG_ON(level != nilfs_btree_node_get_level(node)); index = nilfs_btree_node_get_nchildren(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(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(); if (path == NULL) return -ENOMEM; nilfs_btree_init_path(path); ret = nilfs_btree_do_lookup(btree, path, key, &ptr, level); if (ptrp != NULL) *ptrp = ptr; nilfs_btree_release_path(path); nilfs_btree_free_path(path); return ret; } static int nilfs_btree_lookup_contig(const struct nilfs_bmap *bmap, __u64 key, __u64 *ptrp, unsigned maxblocks) { struct nilfs_btree *btree = (struct nilfs_btree *)bmap; 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; path = nilfs_btree_alloc_path(); if (path == NULL) return -ENOMEM; nilfs_btree_init_path(path); ret = nilfs_btree_do_lookup(btree, path, key, &ptr, level); if (ret < 0) goto out; if (NILFS_BMAP_USE_VBN(bmap)) { dat = nilfs_bmap_get_dat(bmap); 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); 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(btree, node, index); 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 */ node = nilfs_btree_get_node(btree, path, level + 1); index = path[level + 1].bp_index + 1; if (index >= nilfs_btree_node_get_nchildren(node) || nilfs_btree_node_get_key(node, index) != key + cnt) break; ptr2 = nilfs_btree_node_get_ptr(btree, node, index); path[level + 1].bp_index = index; brelse(path[level].bp_bh); path[level].bp_bh = NULL; ret = nilfs_btree_get_block(btree, ptr2, &path[level].bp_bh); if (ret < 0) goto out; node = nilfs_btree_get_nonroot_node(path, level); index = 0; path[level].bp_index = index; } end: *ptrp = ptr; ret = cnt; out: nilfs_btree_release_path(path); nilfs_btree_free_path(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( nilfs_btree_get_nonroot_node(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(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(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(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(path, level); left = nilfs_btree_get_sib_node(path, level); nchildren = nilfs_btree_node_get_nchildren(node); lnchildren = nilfs_btree_node_get_nchildren(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(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_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(path, level); right = nilfs_btree_get_sib_node(path, level); nchildren = nilfs_btree_node_get_nchildren(node); rnchildren = nilfs_btree_node_get_nchildren(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(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_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(path, level); right = nilfs_btree_get_sib_node(path, level); nchildren = nilfs_btree_node_get_nchildren(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(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(btree, right, *keyp, *ptrp, path[level].bp_index); *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_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(path, level); n = nilfs_btree_node_get_nchildren(root); nilfs_btree_node_move_right(btree, root, child, n); nilfs_btree_node_set_level(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(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; 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->bt_bmap)) { path[level].bp_newreq.bpr_ptr = nilfs_btree_find_target_v(btree, path, key); dat = nilfs_bmap_get_dat(&btree->bt_bmap); } ret = nilfs_bmap_prepare_alloc_ptr(&btree->bt_bmap, &path[level].bp_newreq, dat); 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(path, level); if (nilfs_btree_node_get_nchildren(node) < nilfs_btree_node_nchildren_max(node, btree)) { 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_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) < nilfs_btree_node_nchildren_max(sib, btree)) { 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(btree, parent, pindex + 1); 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) < nilfs_btree_node_nchildren_max(sib, btree)) { 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->bt_bmap, &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++; 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(node) < nilfs_btree_node_nchildren_max(node, btree)) { 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->bt_bmap, &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; 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: nilfs_bmap_abort_alloc_ptr(&btree->bt_bmap, &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->bt_bmap, &path[level].bp_newreq, dat); } nilfs_bmap_abort_alloc_ptr(&btree->bt_bmap, &path[level].bp_newreq, dat); 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) { 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->bt_bmap)) { nilfs_btree_set_target_v(btree, key, ptr); dat = nilfs_bmap_get_dat(&btree->bt_bmap); } for (level = NILFS_BTREE_LEVEL_NODE_MIN; level <= maxlevel; level++) { nilfs_bmap_commit_alloc_ptr(&btree->bt_bmap, &path[level - 1].bp_newreq, dat); 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(); if (path == NULL) return -ENOMEM; nilfs_btree_init_path(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_release_path(path); nilfs_btree_free_path(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(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(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(path, level); left = nilfs_btree_get_sib_node(path, level); nchildren = nilfs_btree_node_get_nchildren(node); lnchildren = nilfs_btree_node_get_nchildren(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(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_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(path, level); right = nilfs_btree_get_sib_node(path, level); nchildren = nilfs_btree_node_get_nchildren(node); rnchildren = nilfs_btree_node_get_nchildren(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(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_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(path, level); left = nilfs_btree_get_sib_node(path, level); n = nilfs_btree_node_get_nchildren(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_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_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(path, level); right = nilfs_btree_get_sib_node(path, level); n = nilfs_btree_node_get_nchildren(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_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_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(path, level); nilfs_btree_node_delete(btree, root, NULL, NULL, 0); nilfs_btree_node_set_level(root, level); n = nilfs_btree_node_get_nchildren(child); nilfs_btree_node_move_left(btree, root, child, n); unlock_buffer(path[level].bp_bh); nilfs_btnode_delete(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 inode *dat) { 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(path, level); path[level].bp_oldreq.bpr_ptr = nilfs_btree_node_get_ptr(btree, node, path[level].bp_index); ret = nilfs_bmap_prepare_end_ptr(&btree->bt_bmap, &path[level].bp_oldreq, dat); if (ret < 0) goto err_out_child_node; if (nilfs_btree_node_get_nchildren(node) > nilfs_btree_node_nchildren_min(node, btree)) { 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_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) > nilfs_btree_node_nchildren_min(sib, btree)) { 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(btree, parent, pindex + 1); 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) > nilfs_btree_node_nchildren_min(sib, btree)) { 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 */ 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; } 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); ret = nilfs_bmap_prepare_end_ptr(&btree->bt_bmap, &path[level].bp_oldreq, dat); 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: nilfs_bmap_abort_end_ptr(&btree->bt_bmap, &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->bt_bmap, &path[level].bp_oldreq, dat); } *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, struct inode *dat) { int level; for (level = NILFS_BTREE_LEVEL_NODE_MIN; level <= maxlevel; level++) { nilfs_bmap_commit_end_ptr(&btree->bt_bmap, &path[level].bp_oldreq, dat); 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; struct inode *dat; int level, ret; btree = (struct nilfs_btree *)bmap; path = nilfs_btree_alloc_path(); if (path == NULL) return -ENOMEM; nilfs_btree_init_path(path); ret = nilfs_btree_do_lookup(btree, path, key, NULL, NILFS_BTREE_LEVEL_NODE_MIN); if (ret < 0) goto out; dat = NILFS_BMAP_USE_VBN(&btree->bt_bmap) ? nilfs_bmap_get_dat(&btree->bt_bmap) : 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_bmap_sub_blocks(bmap, stats.bs_nblocks); out: nilfs_btree_release_path(path); nilfs_btree_free_path(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(); if (path == NULL) return -ENOMEM; nilfs_btree_init_path(path); ret = nilfs_btree_do_lookup_last(btree, path, keyp, NULL); nilfs_btree_release_path(path); nilfs_btree_free_path(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(root); if (nchildren > 1) return 0; ptr = nilfs_btree_node_get_ptr(btree, root, nchildren - 1); 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 *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(root); WARN_ON(nchildren > 1); ptr = nilfs_btree_node_get_ptr(btree, root, nchildren - 1); ret = nilfs_btree_get_block(btree, ptr, &bh); if (ret < 0) return ret; node = (struct nilfs_btree_node *)bh->b_data; 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, btree); 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) brelse(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 = (struct nilfs_btree *)bmap; struct inode *dat = NULL; int ret; stats->bs_nblocks = 0; /* for data */ /* cannot find near ptr */ if (NILFS_BMAP_USE_VBN(bmap)) { dreq->bpr_ptr = nilfs_btree_find_target_v(btree, NULL, key); dat = nilfs_bmap_get_dat(bmap); } ret = nilfs_bmap_prepare_alloc_ptr(bmap, 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(bmap, 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(bmap, nreq, dat); err_out_dreq: nilfs_bmap_abort_alloc_ptr(bmap, dreq, dat); 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, union nilfs_bmap_ptr_req *dreq, union nilfs_bmap_ptr_req *nreq, struct buffer_head *bh) { struct nilfs_btree *btree = (struct nilfs_btree *)bmap; struct nilfs_btree_node *node; struct inode *dat; __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 */ dat = NILFS_BMAP_USE_VBN(bmap) ? nilfs_bmap_get_dat(bmap) : NULL; nilfs_btree_init(bmap); if (nreq != NULL) { nilfs_bmap_commit_alloc_ptr(bmap, dreq, dat); nilfs_bmap_commit_alloc_ptr(bmap, nreq, dat); /* 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); brelse(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 { nilfs_bmap_commit_alloc_ptr(bmap, dreq, dat); /* 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 (NILFS_BMAP_USE_VBN(bmap)) nilfs_btree_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 *bmap, __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 << 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, 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 inode *dat) { 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_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->bt_bmap)->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_btree *btree, struct nilfs_btree_path *path, int level, struct inode *dat) { struct nilfs_btree_node *parent; nilfs_dat_commit_update(dat, &path[level].bp_oldreq.bpr_req, &path[level].bp_newreq.bpr_req, btree->bt_bmap.b_ptr_type == NILFS_BMAP_PTR_VS); 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, 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->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, 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_btree *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_btree *btree, struct nilfs_btree_path *path, int level, struct buffer_head *bh) { int maxlevel, ret; struct nilfs_btree_node *parent; struct inode *dat = nilfs_bmap_get_dat(&btree->bt_bmap); __u64 ptr; 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); ptr = nilfs_btree_node_get_ptr(btree, parent, path[level + 1].bp_index); 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(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; WARN_ON(!buffer_dirty(bh)); btree = (struct nilfs_btree *)bmap; path = nilfs_btree_alloc_path(); if (path == NULL) return -ENOMEM; nilfs_btree_init_path(path); 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(bmap, bh); level = NILFS_BTREE_LEVEL_DATA; } ret = nilfs_btree_do_lookup(btree, path, key, NULL, level + 1); 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(bmap) ? nilfs_btree_propagate_v(btree, path, level, bh) : nilfs_btree_propagate_p(btree, path, level, bh); out: nilfs_btree_release_path(path); nilfs_btree_free_path(path); return ret; } static int nilfs_btree_propagate_gc(const struct nilfs_bmap *bmap, struct buffer_head *bh) { return nilfs_dat_mark_dirty(nilfs_bmap_get_dat(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(node, 0); level = nilfs_btree_node_get_level(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(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(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; struct inode *dat = nilfs_bmap_get_dat(&btree->bt_bmap); __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 = 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 = 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(); if (path == NULL) return -ENOMEM; nilfs_btree_init_path(path); 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(bmap, *bh); level = NILFS_BTREE_LEVEL_DATA; } ret = nilfs_btree_do_lookup(btree, path, key, NULL, level + 1); if (ret < 0) { WARN_ON(ret == -ENOENT); goto out; } ret = NILFS_BMAP_USE_VBN(bmap) ? nilfs_btree_assign_v(btree, path, level, bh, blocknr, binfo) : nilfs_btree_assign_p(btree, path, level, bh, blocknr, binfo); out: nilfs_btree_release_path(path); nilfs_btree_free_path(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_node *node; __u64 key; int ret; ret = nilfs_dat_move(nilfs_bmap_get_dat(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(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(); if (path == NULL) return -ENOMEM; nilfs_btree_init_path(path); ret = nilfs_btree_do_lookup(btree, path, key, &ptr, level + 1); 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)) nilfs_btnode_mark_dirty(bh); brelse(bh); if (!nilfs_bmap_dirty(&btree->bt_bmap)) nilfs_bmap_set_dirty(&btree->bt_bmap); out: nilfs_btree_release_path(path); 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_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_last_key = NULL, .bop_check_insert = NULL, .bop_check_delete = NULL, .bop_gather_data = NULL, }; int nilfs_btree_init(struct nilfs_bmap *bmap) { bmap->b_ops = &nilfs_btree_ops; return 0; } void nilfs_btree_init_gc(struct nilfs_bmap *bmap) { bmap->b_ops = &nilfs_btree_ops_gc; }