diff options
Diffstat (limited to 'fs/btrfs/tree-mod-log.c')
| -rw-r--r-- | fs/btrfs/tree-mod-log.c | 364 |
1 files changed, 288 insertions, 76 deletions
diff --git a/fs/btrfs/tree-mod-log.c b/fs/btrfs/tree-mod-log.c index a555baa0143a..9e8cb3b7c064 100644 --- a/fs/btrfs/tree-mod-log.c +++ b/fs/btrfs/tree-mod-log.c @@ -27,24 +27,35 @@ struct tree_mod_elem { /* This is used for BTRFS_MOD_LOG_KEY* and BTRFS_MOD_LOG_ROOT_REPLACE. */ u64 generation; - /* Those are used for op == BTRFS_MOD_LOG_KEY_{REPLACE,REMOVE}. */ - struct btrfs_disk_key key; - u64 blockptr; - - /* This is used for op == BTRFS_MOD_LOG_MOVE_KEYS. */ - struct { - int dst_slot; - int nr_items; - } move; - - /* This is used for op == BTRFS_MOD_LOG_ROOT_REPLACE. */ - struct tree_mod_root old_root; + union { + /* + * This is used for the following op types: + * + * BTRFS_MOD_LOG_KEY_REMOVE_WHILE_FREEING + * BTRFS_MOD_LOG_KEY_REMOVE_WHILE_MOVING + * BTRFS_MOD_LOG_KEY_REMOVE + * BTRFS_MOD_LOG_KEY_REPLACE + */ + struct { + struct btrfs_disk_key key; + u64 blockptr; + } slot_change; + + /* This is used for op == BTRFS_MOD_LOG_MOVE_KEYS. */ + struct { + int dst_slot; + int nr_items; + } move; + + /* This is used for op == BTRFS_MOD_LOG_ROOT_REPLACE. */ + struct tree_mod_root old_root; + }; }; /* * Pull a new tree mod seq number for our operation. */ -static inline u64 btrfs_inc_tree_mod_seq(struct btrfs_fs_info *fs_info) +static u64 btrfs_inc_tree_mod_seq(struct btrfs_fs_info *fs_info) { return atomic64_inc_return(&fs_info->tree_mod_seq); } @@ -164,18 +175,41 @@ static noinline int tree_mod_log_insert(struct btrfs_fs_info *fs_info, return 0; } +static inline bool skip_eb_logging(const struct extent_buffer *eb) +{ + const u64 owner = btrfs_header_owner(eb); + + if (btrfs_header_level(eb) == 0) + return true; + + /* + * Tree mod logging exists so that there's a consistent view of the + * extents and backrefs of inodes even if while a task is iterating over + * them other tasks are modifying subvolume trees and the extent tree + * (including running delayed refs). So we only need to log extent + * buffers from the extent tree and subvolume trees. + */ + + if (owner == BTRFS_EXTENT_TREE_OBJECTID) + return false; + + if (btrfs_is_fstree(owner)) + return false; + + return true; +} + /* * Determines if logging can be omitted. Returns true if it can. Otherwise, it * returns false with the tree_mod_log_lock acquired. The caller must hold * this until all tree mod log insertions are recorded in the rb tree and then * write unlock fs_info::tree_mod_log_lock. */ -static inline bool tree_mod_dont_log(struct btrfs_fs_info *fs_info, - struct extent_buffer *eb) +static bool tree_mod_dont_log(struct btrfs_fs_info *fs_info, const struct extent_buffer *eb) { if (!test_bit(BTRFS_FS_TREE_MOD_LOG_USERS, &fs_info->flags)) return true; - if (eb && btrfs_header_level(eb) == 0) + if (eb && skip_eb_logging(eb)) return true; write_lock(&fs_info->tree_mod_log_lock); @@ -188,32 +222,34 @@ static inline bool tree_mod_dont_log(struct btrfs_fs_info *fs_info, } /* Similar to tree_mod_dont_log, but doesn't acquire any locks. */ -static inline bool tree_mod_need_log(const struct btrfs_fs_info *fs_info, - struct extent_buffer *eb) +static bool tree_mod_need_log(const struct btrfs_fs_info *fs_info, + const struct extent_buffer *eb) { if (!test_bit(BTRFS_FS_TREE_MOD_LOG_USERS, &fs_info->flags)) return false; - if (eb && btrfs_header_level(eb) == 0) + if (eb && skip_eb_logging(eb)) return false; return true; } -static struct tree_mod_elem *alloc_tree_mod_elem(struct extent_buffer *eb, +static struct tree_mod_elem *alloc_tree_mod_elem(const struct extent_buffer *eb, int slot, enum btrfs_mod_log_op op) { struct tree_mod_elem *tm; + /* Can't be one of these types, due to union in struct tree_mod_elem. */ + ASSERT(op != BTRFS_MOD_LOG_MOVE_KEYS); + ASSERT(op != BTRFS_MOD_LOG_ROOT_REPLACE); + tm = kzalloc(sizeof(*tm), GFP_NOFS); if (!tm) return NULL; tm->logical = eb->start; - if (op != BTRFS_MOD_LOG_KEY_ADD) { - btrfs_node_key(eb, &tm->key, slot); - tm->blockptr = btrfs_node_blockptr(eb, slot); - } + btrfs_node_key(eb, &tm->slot_change.key, slot); + tm->slot_change.blockptr = btrfs_node_blockptr(eb, slot); tm->op = op; tm->slot = slot; tm->generation = btrfs_node_ptr_generation(eb, slot); @@ -222,25 +258,36 @@ static struct tree_mod_elem *alloc_tree_mod_elem(struct extent_buffer *eb, return tm; } -int btrfs_tree_mod_log_insert_key(struct extent_buffer *eb, int slot, +int btrfs_tree_mod_log_insert_key(const struct extent_buffer *eb, int slot, enum btrfs_mod_log_op op) { struct tree_mod_elem *tm; - int ret; + int ret = 0; if (!tree_mod_need_log(eb->fs_info, eb)) return 0; tm = alloc_tree_mod_elem(eb, slot, op); if (!tm) - return -ENOMEM; + ret = -ENOMEM; if (tree_mod_dont_log(eb->fs_info, eb)) { kfree(tm); + /* + * Don't error if we failed to allocate memory because we don't + * need to log. + */ return 0; + } else if (ret != 0) { + /* + * We previously failed to allocate memory and we need to log, + * so we have to fail. + */ + goto out_unlock; } ret = tree_mod_log_insert(eb->fs_info, tm); +out_unlock: write_unlock(&eb->fs_info->tree_mod_log_lock); if (ret) kfree(tm); @@ -248,7 +295,27 @@ int btrfs_tree_mod_log_insert_key(struct extent_buffer *eb, int slot, return ret; } -int btrfs_tree_mod_log_insert_move(struct extent_buffer *eb, +static struct tree_mod_elem *tree_mod_log_alloc_move(const struct extent_buffer *eb, + int dst_slot, int src_slot, + int nr_items) +{ + struct tree_mod_elem *tm; + + tm = kzalloc(sizeof(*tm), GFP_NOFS); + if (!tm) + return ERR_PTR(-ENOMEM); + + tm->logical = eb->start; + tm->slot = src_slot; + tm->move.dst_slot = dst_slot; + tm->move.nr_items = nr_items; + tm->op = BTRFS_MOD_LOG_MOVE_KEYS; + RB_CLEAR_NODE(&tm->node); + + return tm; +} + +int btrfs_tree_mod_log_insert_move(const struct extent_buffer *eb, int dst_slot, int src_slot, int nr_items) { @@ -262,35 +329,46 @@ int btrfs_tree_mod_log_insert_move(struct extent_buffer *eb, return 0; tm_list = kcalloc(nr_items, sizeof(struct tree_mod_elem *), GFP_NOFS); - if (!tm_list) - return -ENOMEM; - - tm = kzalloc(sizeof(*tm), GFP_NOFS); - if (!tm) { + if (!tm_list) { ret = -ENOMEM; - goto free_tms; + goto lock; } - tm->logical = eb->start; - tm->slot = src_slot; - tm->move.dst_slot = dst_slot; - tm->move.nr_items = nr_items; - tm->op = BTRFS_MOD_LOG_MOVE_KEYS; + tm = tree_mod_log_alloc_move(eb, dst_slot, src_slot, nr_items); + if (IS_ERR(tm)) { + ret = PTR_ERR(tm); + tm = NULL; + goto lock; + } for (i = 0; i + dst_slot < src_slot && i < nr_items; i++) { tm_list[i] = alloc_tree_mod_elem(eb, i + dst_slot, BTRFS_MOD_LOG_KEY_REMOVE_WHILE_MOVING); if (!tm_list[i]) { ret = -ENOMEM; - goto free_tms; + goto lock; } } - if (tree_mod_dont_log(eb->fs_info, eb)) +lock: + if (tree_mod_dont_log(eb->fs_info, eb)) { + /* + * Don't error if we failed to allocate memory because we don't + * need to log. + */ + ret = 0; goto free_tms; + } locked = true; /* + * We previously failed to allocate memory and we need to log, so we + * have to fail. + */ + if (ret != 0) + goto free_tms; + + /* * When we override something during the move, we log these removals. * This can only happen when we move towards the beginning of the * buffer, i.e. dst_slot < src_slot. @@ -310,10 +388,12 @@ int btrfs_tree_mod_log_insert_move(struct extent_buffer *eb, return 0; free_tms: - for (i = 0; i < nr_items; i++) { - if (tm_list[i] && !RB_EMPTY_NODE(&tm_list[i]->node)) - rb_erase(&tm_list[i]->node, &eb->fs_info->tree_mod_log); - kfree(tm_list[i]); + if (tm_list) { + for (i = 0; i < nr_items; i++) { + if (tm_list[i] && !RB_EMPTY_NODE(&tm_list[i]->node)) + rb_erase(&tm_list[i]->node, &eb->fs_info->tree_mod_log); + kfree(tm_list[i]); + } } if (locked) write_unlock(&eb->fs_info->tree_mod_log_lock); @@ -323,9 +403,9 @@ free_tms: return ret; } -static inline int tree_mod_log_free_eb(struct btrfs_fs_info *fs_info, - struct tree_mod_elem **tm_list, - int nritems) +static int tree_mod_log_free_eb(struct btrfs_fs_info *fs_info, + struct tree_mod_elem **tm_list, + int nritems) { int i, j; int ret; @@ -363,14 +443,14 @@ int btrfs_tree_mod_log_insert_root(struct extent_buffer *old_root, GFP_NOFS); if (!tm_list) { ret = -ENOMEM; - goto free_tms; + goto lock; } for (i = 0; i < nritems; i++) { tm_list[i] = alloc_tree_mod_elem(old_root, i, BTRFS_MOD_LOG_KEY_REMOVE_WHILE_FREEING); if (!tm_list[i]) { ret = -ENOMEM; - goto free_tms; + goto lock; } } } @@ -378,7 +458,7 @@ int btrfs_tree_mod_log_insert_root(struct extent_buffer *old_root, tm = kzalloc(sizeof(*tm), GFP_NOFS); if (!tm) { ret = -ENOMEM; - goto free_tms; + goto lock; } tm->logical = new_root->start; @@ -387,14 +467,28 @@ int btrfs_tree_mod_log_insert_root(struct extent_buffer *old_root, tm->generation = btrfs_header_generation(old_root); tm->op = BTRFS_MOD_LOG_ROOT_REPLACE; - if (tree_mod_dont_log(fs_info, NULL)) +lock: + if (tree_mod_dont_log(fs_info, NULL)) { + /* + * Don't error if we failed to allocate memory because we don't + * need to log. + */ + ret = 0; goto free_tms; + } else if (ret != 0) { + /* + * We previously failed to allocate memory and we need to log, + * so we have to fail. + */ + goto out_unlock; + } if (tm_list) ret = tree_mod_log_free_eb(fs_info, tm_list, nritems); if (!ret) ret = tree_mod_log_insert(fs_info, tm); +out_unlock: write_unlock(&fs_info->tree_mod_log_lock); if (ret) goto free_tms; @@ -478,7 +572,7 @@ static struct tree_mod_elem *tree_mod_log_search(struct btrfs_fs_info *fs_info, } int btrfs_tree_mod_log_eb_copy(struct extent_buffer *dst, - struct extent_buffer *src, + const struct extent_buffer *src, unsigned long dst_offset, unsigned long src_offset, int nr_items) @@ -486,9 +580,14 @@ int btrfs_tree_mod_log_eb_copy(struct extent_buffer *dst, struct btrfs_fs_info *fs_info = dst->fs_info; int ret = 0; struct tree_mod_elem **tm_list = NULL; - struct tree_mod_elem **tm_list_add, **tm_list_rem; + struct tree_mod_elem **tm_list_add = NULL; + struct tree_mod_elem **tm_list_rem = NULL; int i; bool locked = false; + struct tree_mod_elem *dst_move_tm = NULL; + struct tree_mod_elem *src_move_tm = NULL; + u32 dst_move_nr_items = btrfs_header_nritems(dst) - dst_offset; + u32 src_move_nr_items = btrfs_header_nritems(src) - (src_offset + nr_items); if (!tree_mod_need_log(fs_info, NULL)) return 0; @@ -498,8 +597,30 @@ int btrfs_tree_mod_log_eb_copy(struct extent_buffer *dst, tm_list = kcalloc(nr_items * 2, sizeof(struct tree_mod_elem *), GFP_NOFS); - if (!tm_list) - return -ENOMEM; + if (!tm_list) { + ret = -ENOMEM; + goto lock; + } + + if (dst_move_nr_items) { + dst_move_tm = tree_mod_log_alloc_move(dst, dst_offset + nr_items, + dst_offset, dst_move_nr_items); + if (IS_ERR(dst_move_tm)) { + ret = PTR_ERR(dst_move_tm); + dst_move_tm = NULL; + goto lock; + } + } + if (src_move_nr_items) { + src_move_tm = tree_mod_log_alloc_move(src, src_offset, + src_offset + nr_items, + src_move_nr_items); + if (IS_ERR(src_move_tm)) { + ret = PTR_ERR(src_move_tm); + src_move_tm = NULL; + goto lock; + } + } tm_list_add = tm_list; tm_list_rem = tm_list + nr_items; @@ -508,21 +629,40 @@ int btrfs_tree_mod_log_eb_copy(struct extent_buffer *dst, BTRFS_MOD_LOG_KEY_REMOVE); if (!tm_list_rem[i]) { ret = -ENOMEM; - goto free_tms; + goto lock; } tm_list_add[i] = alloc_tree_mod_elem(dst, i + dst_offset, BTRFS_MOD_LOG_KEY_ADD); if (!tm_list_add[i]) { ret = -ENOMEM; - goto free_tms; + goto lock; } } - if (tree_mod_dont_log(fs_info, NULL)) +lock: + if (tree_mod_dont_log(fs_info, NULL)) { + /* + * Don't error if we failed to allocate memory because we don't + * need to log. + */ + ret = 0; goto free_tms; + } locked = true; + /* + * We previously failed to allocate memory and we need to log, so we + * have to fail. + */ + if (ret != 0) + goto free_tms; + + if (dst_move_tm) { + ret = tree_mod_log_insert(fs_info, dst_move_tm); + if (ret) + goto free_tms; + } for (i = 0; i < nr_items; i++) { ret = tree_mod_log_insert(fs_info, tm_list_rem[i]); if (ret) @@ -531,6 +671,11 @@ int btrfs_tree_mod_log_eb_copy(struct extent_buffer *dst, if (ret) goto free_tms; } + if (src_move_tm) { + ret = tree_mod_log_insert(fs_info, src_move_tm); + if (ret) + goto free_tms; + } write_unlock(&fs_info->tree_mod_log_lock); kfree(tm_list); @@ -538,10 +683,18 @@ int btrfs_tree_mod_log_eb_copy(struct extent_buffer *dst, return 0; free_tms: - for (i = 0; i < nr_items * 2; i++) { - if (tm_list[i] && !RB_EMPTY_NODE(&tm_list[i]->node)) - rb_erase(&tm_list[i]->node, &fs_info->tree_mod_log); - kfree(tm_list[i]); + if (dst_move_tm && !RB_EMPTY_NODE(&dst_move_tm->node)) + rb_erase(&dst_move_tm->node, &fs_info->tree_mod_log); + kfree(dst_move_tm); + if (src_move_tm && !RB_EMPTY_NODE(&src_move_tm->node)) + rb_erase(&src_move_tm->node, &fs_info->tree_mod_log); + kfree(src_move_tm); + if (tm_list) { + for (i = 0; i < nr_items * 2; i++) { + if (tm_list[i] && !RB_EMPTY_NODE(&tm_list[i]->node)) + rb_erase(&tm_list[i]->node, &fs_info->tree_mod_log); + kfree(tm_list[i]); + } } if (locked) write_unlock(&fs_info->tree_mod_log_lock); @@ -562,22 +715,38 @@ int btrfs_tree_mod_log_free_eb(struct extent_buffer *eb) nritems = btrfs_header_nritems(eb); tm_list = kcalloc(nritems, sizeof(struct tree_mod_elem *), GFP_NOFS); - if (!tm_list) - return -ENOMEM; + if (!tm_list) { + ret = -ENOMEM; + goto lock; + } for (i = 0; i < nritems; i++) { tm_list[i] = alloc_tree_mod_elem(eb, i, BTRFS_MOD_LOG_KEY_REMOVE_WHILE_FREEING); if (!tm_list[i]) { ret = -ENOMEM; - goto free_tms; + goto lock; } } - if (tree_mod_dont_log(eb->fs_info, eb)) +lock: + if (tree_mod_dont_log(eb->fs_info, eb)) { + /* + * Don't error if we failed to allocate memory because we don't + * need to log. + */ + ret = 0; goto free_tms; + } else if (ret != 0) { + /* + * We previously failed to allocate memory and we need to log, + * so we have to fail. + */ + goto out_unlock; + } ret = tree_mod_log_free_eb(eb->fs_info, tm_list, nritems); +out_unlock: write_unlock(&eb->fs_info->tree_mod_log_lock); if (ret) goto free_tms; @@ -586,9 +755,11 @@ int btrfs_tree_mod_log_free_eb(struct extent_buffer *eb) return 0; free_tms: - for (i = 0; i < nritems; i++) - kfree(tm_list[i]); - kfree(tm_list); + if (tm_list) { + for (i = 0; i < nritems; i++) + kfree(tm_list[i]); + kfree(tm_list); + } return ret; } @@ -664,10 +835,27 @@ static void tree_mod_log_rewind(struct btrfs_fs_info *fs_info, unsigned long o_dst; unsigned long o_src; unsigned long p_size = sizeof(struct btrfs_key_ptr); + /* + * max_slot tracks the maximum valid slot of the rewind eb at every + * step of the rewind. This is in contrast with 'n' which eventually + * matches the number of items, but can be wrong during moves or if + * removes overlap on already valid slots (which is probably separately + * a bug). We do this to validate the offsets of memmoves for rewinding + * moves and detect invalid memmoves. + * + * Since a rewind eb can start empty, max_slot is a signed integer with + * a special meaning for -1, which is that no slot is valid to move out + * of. Any other negative value is invalid. + */ + int max_slot; + int move_src_end_slot; + int move_dst_end_slot; n = btrfs_header_nritems(eb); + max_slot = n - 1; read_lock(&fs_info->tree_mod_log_lock); while (tm && tm->seq >= time_seq) { + ASSERT(max_slot >= -1); /* * All the operations are recorded with the operator used for * the modification. As we're going backwards, we do the @@ -679,28 +867,53 @@ static void tree_mod_log_rewind(struct btrfs_fs_info *fs_info, fallthrough; case BTRFS_MOD_LOG_KEY_REMOVE_WHILE_MOVING: case BTRFS_MOD_LOG_KEY_REMOVE: - btrfs_set_node_key(eb, &tm->key, tm->slot); - btrfs_set_node_blockptr(eb, tm->slot, tm->blockptr); + btrfs_set_node_key(eb, &tm->slot_change.key, tm->slot); + btrfs_set_node_blockptr(eb, tm->slot, tm->slot_change.blockptr); btrfs_set_node_ptr_generation(eb, tm->slot, tm->generation); n++; + if (tm->slot > max_slot) + max_slot = tm->slot; break; case BTRFS_MOD_LOG_KEY_REPLACE: BUG_ON(tm->slot >= n); - btrfs_set_node_key(eb, &tm->key, tm->slot); - btrfs_set_node_blockptr(eb, tm->slot, tm->blockptr); + btrfs_set_node_key(eb, &tm->slot_change.key, tm->slot); + btrfs_set_node_blockptr(eb, tm->slot, tm->slot_change.blockptr); btrfs_set_node_ptr_generation(eb, tm->slot, tm->generation); break; case BTRFS_MOD_LOG_KEY_ADD: + /* + * It is possible we could have already removed keys + * behind the known max slot, so this will be an + * overestimate. In practice, the copy operation + * inserts them in increasing order, and overestimating + * just means we miss some warnings, so it's OK. It + * isn't worth carefully tracking the full array of + * valid slots to check against when moving. + */ + if (tm->slot == max_slot) + max_slot--; /* if a move operation is needed it's in the log */ n--; break; case BTRFS_MOD_LOG_MOVE_KEYS: + ASSERT(tm->move.nr_items > 0); + move_src_end_slot = tm->move.dst_slot + tm->move.nr_items - 1; + move_dst_end_slot = tm->slot + tm->move.nr_items - 1; o_dst = btrfs_node_key_ptr_offset(eb, tm->slot); o_src = btrfs_node_key_ptr_offset(eb, tm->move.dst_slot); + if (WARN_ON(move_src_end_slot > max_slot || + tm->move.nr_items <= 0)) { + btrfs_warn(fs_info, +"move from invalid tree mod log slot eb %llu slot %d dst_slot %d nr_items %d seq %llu n %u max_slot %d", + eb->start, tm->slot, + tm->move.dst_slot, tm->move.nr_items, + tm->seq, n, max_slot); + } memmove_extent_buffer(eb, o_dst, o_src, tm->move.nr_items * p_size); + max_slot = move_dst_end_slot; break; case BTRFS_MOD_LOG_ROOT_REPLACE: /* @@ -733,7 +946,6 @@ static void tree_mod_log_rewind(struct btrfs_fs_info *fs_info, * is freed (its refcount is decremented). */ struct extent_buffer *btrfs_tree_mod_log_rewind(struct btrfs_fs_info *fs_info, - struct btrfs_path *path, struct extent_buffer *eb, u64 time_seq) { @@ -828,7 +1040,7 @@ struct extent_buffer *btrfs_get_old_root(struct btrfs_root *root, u64 time_seq) free_extent_buffer(eb_root); check.level = level; - check.owner_root = root->root_key.objectid; + check.owner_root = btrfs_root_id(root); old = read_tree_block(fs_info, logical, &check); if (WARN_ON(IS_ERR(old) || !extent_buffer_uptodate(old))) { |
