diff options
Diffstat (limited to 'fs/btrfs/backref.c')
| -rw-r--r-- | fs/btrfs/backref.c | 1308 |
1 files changed, 895 insertions, 413 deletions
diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c index 633c701a287..e25564bfcb4 100644 --- a/fs/btrfs/backref.c +++ b/fs/btrfs/backref.c @@ -16,12 +16,104 @@ * Boston, MA 021110-1307, USA. */ +#include <linux/vmalloc.h> #include "ctree.h" #include "disk-io.h" #include "backref.h" #include "ulist.h" #include "transaction.h" #include "delayed-ref.h" +#include "locking.h" + +struct extent_inode_elem { + u64 inum; + u64 offset; + struct extent_inode_elem *next; +}; + +static int check_extent_in_eb(struct btrfs_key *key, struct extent_buffer *eb, + struct btrfs_file_extent_item *fi, + u64 extent_item_pos, + struct extent_inode_elem **eie) +{ + u64 offset = 0; + struct extent_inode_elem *e; + + if (!btrfs_file_extent_compression(eb, fi) && + !btrfs_file_extent_encryption(eb, fi) && + !btrfs_file_extent_other_encoding(eb, fi)) { + u64 data_offset; + u64 data_len; + + data_offset = btrfs_file_extent_offset(eb, fi); + data_len = btrfs_file_extent_num_bytes(eb, fi); + + if (extent_item_pos < data_offset || + extent_item_pos >= data_offset + data_len) + return 1; + offset = extent_item_pos - data_offset; + } + + e = kmalloc(sizeof(*e), GFP_NOFS); + if (!e) + return -ENOMEM; + + e->next = *eie; + e->inum = key->objectid; + e->offset = key->offset + offset; + *eie = e; + + return 0; +} + +static void free_inode_elem_list(struct extent_inode_elem *eie) +{ + struct extent_inode_elem *eie_next; + + for (; eie; eie = eie_next) { + eie_next = eie->next; + kfree(eie); + } +} + +static int find_extent_in_eb(struct extent_buffer *eb, u64 wanted_disk_byte, + u64 extent_item_pos, + struct extent_inode_elem **eie) +{ + u64 disk_byte; + struct btrfs_key key; + struct btrfs_file_extent_item *fi; + int slot; + int nritems; + int extent_type; + int ret; + + /* + * from the shared data ref, we only have the leaf but we need + * the key. thus, we must look into all items and see that we + * find one (some) with a reference to our extent item. + */ + nritems = btrfs_header_nritems(eb); + for (slot = 0; slot < nritems; ++slot) { + btrfs_item_key_to_cpu(eb, &key, slot); + if (key.type != BTRFS_EXTENT_DATA_KEY) + continue; + fi = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item); + extent_type = btrfs_file_extent_type(eb, fi); + if (extent_type == BTRFS_FILE_EXTENT_INLINE) + continue; + /* don't skip BTRFS_FILE_EXTENT_PREALLOC, we can handle that */ + disk_byte = btrfs_file_extent_disk_bytenr(eb, fi); + if (disk_byte != wanted_disk_byte) + continue; + + ret = check_extent_in_eb(&key, eb, fi, extent_item_pos, eie); + if (ret < 0) + return ret; + } + + return 0; +} /* * this structure records all encountered refs on the way up to the root @@ -29,30 +121,94 @@ struct __prelim_ref { struct list_head list; u64 root_id; - struct btrfs_key key; + struct btrfs_key key_for_search; int level; int count; + struct extent_inode_elem *inode_list; u64 parent; u64 wanted_disk_byte; }; +static struct kmem_cache *btrfs_prelim_ref_cache; + +int __init btrfs_prelim_ref_init(void) +{ + btrfs_prelim_ref_cache = kmem_cache_create("btrfs_prelim_ref", + sizeof(struct __prelim_ref), + 0, + SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, + NULL); + if (!btrfs_prelim_ref_cache) + return -ENOMEM; + return 0; +} + +void btrfs_prelim_ref_exit(void) +{ + if (btrfs_prelim_ref_cache) + kmem_cache_destroy(btrfs_prelim_ref_cache); +} + +/* + * the rules for all callers of this function are: + * - obtaining the parent is the goal + * - if you add a key, you must know that it is a correct key + * - if you cannot add the parent or a correct key, then we will look into the + * block later to set a correct key + * + * delayed refs + * ============ + * backref type | shared | indirect | shared | indirect + * information | tree | tree | data | data + * --------------------+--------+----------+--------+---------- + * parent logical | y | - | - | - + * key to resolve | - | y | y | y + * tree block logical | - | - | - | - + * root for resolving | y | y | y | y + * + * - column 1: we've the parent -> done + * - column 2, 3, 4: we use the key to find the parent + * + * on disk refs (inline or keyed) + * ============================== + * backref type | shared | indirect | shared | indirect + * information | tree | tree | data | data + * --------------------+--------+----------+--------+---------- + * parent logical | y | - | y | - + * key to resolve | - | - | - | y + * tree block logical | y | y | y | y + * root for resolving | - | y | y | y + * + * - column 1, 3: we've the parent -> done + * - column 2: we take the first key from the block to find the parent + * (see __add_missing_keys) + * - column 4: we use the key to find the parent + * + * additional information that's available but not required to find the parent + * block might help in merging entries to gain some speed. + */ + static int __add_prelim_ref(struct list_head *head, u64 root_id, - struct btrfs_key *key, int level, u64 parent, - u64 wanted_disk_byte, int count) + struct btrfs_key *key, int level, + u64 parent, u64 wanted_disk_byte, int count, + gfp_t gfp_mask) { struct __prelim_ref *ref; - /* in case we're adding delayed refs, we're holding the refs spinlock */ - ref = kmalloc(sizeof(*ref), GFP_ATOMIC); + if (root_id == BTRFS_DATA_RELOC_TREE_OBJECTID) + return 0; + + ref = kmem_cache_alloc(btrfs_prelim_ref_cache, gfp_mask); if (!ref) return -ENOMEM; ref->root_id = root_id; if (key) - ref->key = *key; + ref->key_for_search = *key; else - memset(&ref->key, 0, sizeof(ref->key)); + memset(&ref->key_for_search, 0, sizeof(ref->key_for_search)); + ref->inode_list = NULL; ref->level = level; ref->count = count; ref->parent = parent; @@ -63,52 +219,84 @@ static int __add_prelim_ref(struct list_head *head, u64 root_id, } static int add_all_parents(struct btrfs_root *root, struct btrfs_path *path, - struct ulist *parents, - struct extent_buffer *eb, int level, - u64 wanted_objectid, u64 wanted_disk_byte) + struct ulist *parents, struct __prelim_ref *ref, + int level, u64 time_seq, const u64 *extent_item_pos, + u64 total_refs) { - int ret; + int ret = 0; int slot; - struct btrfs_file_extent_item *fi; + struct extent_buffer *eb; struct btrfs_key key; + struct btrfs_key *key_for_search = &ref->key_for_search; + struct btrfs_file_extent_item *fi; + struct extent_inode_elem *eie = NULL, *old = NULL; u64 disk_byte; + u64 wanted_disk_byte = ref->wanted_disk_byte; + u64 count = 0; -add_parent: - ret = ulist_add(parents, eb->start, 0, GFP_NOFS); - if (ret < 0) - return ret; - - if (level != 0) + if (level != 0) { + eb = path->nodes[level]; + ret = ulist_add(parents, eb->start, 0, GFP_NOFS); + if (ret < 0) + return ret; return 0; + } /* - * if the current leaf is full with EXTENT_DATA items, we must - * check the next one if that holds a reference as well. - * ref->count cannot be used to skip this check. - * repeat this until we don't find any additional EXTENT_DATA items. + * We normally enter this function with the path already pointing to + * the first item to check. But sometimes, we may enter it with + * slot==nritems. In that case, go to the next leaf before we continue. */ - while (1) { - ret = btrfs_next_leaf(root, path); - if (ret < 0) - return ret; - if (ret) - return 0; + if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) + ret = btrfs_next_old_leaf(root, path, time_seq); + while (!ret && count < total_refs) { eb = path->nodes[0]; - for (slot = 0; slot < btrfs_header_nritems(eb); ++slot) { - btrfs_item_key_to_cpu(eb, &key, slot); - if (key.objectid != wanted_objectid || - key.type != BTRFS_EXTENT_DATA_KEY) - return 0; - fi = btrfs_item_ptr(eb, slot, - struct btrfs_file_extent_item); - disk_byte = btrfs_file_extent_disk_bytenr(eb, fi); - if (disk_byte == wanted_disk_byte) - goto add_parent; + slot = path->slots[0]; + + btrfs_item_key_to_cpu(eb, &key, slot); + + if (key.objectid != key_for_search->objectid || + key.type != BTRFS_EXTENT_DATA_KEY) + break; + + fi = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item); + disk_byte = btrfs_file_extent_disk_bytenr(eb, fi); + + if (disk_byte == wanted_disk_byte) { + eie = NULL; + old = NULL; + count++; + if (extent_item_pos) { + ret = check_extent_in_eb(&key, eb, fi, + *extent_item_pos, + &eie); + if (ret < 0) + break; + } + if (ret > 0) + goto next; + ret = ulist_add_merge(parents, eb->start, + (uintptr_t)eie, + (u64 *)&old, GFP_NOFS); + if (ret < 0) + break; + if (!ret && extent_item_pos) { + while (old->next) + old = old->next; + old->next = eie; + } + eie = NULL; } +next: + ret = btrfs_next_old_item(root, path, time_seq); } - return 0; + if (ret > 0) + ret = 0; + else if (ret < 0) + free_inode_elem_list(eie); + return ret; } /* @@ -116,71 +304,71 @@ add_parent: * to a logical address */ static int __resolve_indirect_ref(struct btrfs_fs_info *fs_info, - struct __prelim_ref *ref, - struct ulist *parents) + struct btrfs_path *path, u64 time_seq, + struct __prelim_ref *ref, + struct ulist *parents, + const u64 *extent_item_pos, u64 total_refs) { - struct btrfs_path *path; struct btrfs_root *root; struct btrfs_key root_key; - struct btrfs_key key = {0}; struct extent_buffer *eb; int ret = 0; int root_level; int level = ref->level; - - path = btrfs_alloc_path(); - if (!path) - return -ENOMEM; + int index; root_key.objectid = ref->root_id; root_key.type = BTRFS_ROOT_ITEM_KEY; root_key.offset = (u64)-1; + + index = srcu_read_lock(&fs_info->subvol_srcu); + root = btrfs_read_fs_root_no_name(fs_info, &root_key); if (IS_ERR(root)) { + srcu_read_unlock(&fs_info->subvol_srcu, index); ret = PTR_ERR(root); goto out; } - rcu_read_lock(); - root_level = btrfs_header_level(root->node); - rcu_read_unlock(); + if (path->search_commit_root) + root_level = btrfs_header_level(root->commit_root); + else + root_level = btrfs_old_root_level(root, time_seq); - if (root_level + 1 == level) + if (root_level + 1 == level) { + srcu_read_unlock(&fs_info->subvol_srcu, index); goto out; + } path->lowest_level = level; - ret = btrfs_search_slot(NULL, root, &ref->key, path, 0, 0); + ret = btrfs_search_old_slot(root, &ref->key_for_search, path, time_seq); + + /* root node has been locked, we can release @subvol_srcu safely here */ + srcu_read_unlock(&fs_info->subvol_srcu, index); + pr_debug("search slot in root %llu (level %d, ref count %d) returned " "%d for key (%llu %u %llu)\n", - (unsigned long long)ref->root_id, level, ref->count, ret, - (unsigned long long)ref->key.objectid, ref->key.type, - (unsigned long long)ref->key.offset); + ref->root_id, level, ref->count, ret, + ref->key_for_search.objectid, ref->key_for_search.type, + ref->key_for_search.offset); if (ret < 0) goto out; eb = path->nodes[level]; - if (!eb) { - WARN_ON(1); - ret = 1; - goto out; - } - - if (level == 0) { - if (ret == 1 && path->slots[0] >= btrfs_header_nritems(eb)) { - ret = btrfs_next_leaf(root, path); - if (ret) - goto out; - eb = path->nodes[0]; + while (!eb) { + if (WARN_ON(!level)) { + ret = 1; + goto out; } - - btrfs_item_key_to_cpu(eb, &key, path->slots[0]); + level--; + eb = path->nodes[level]; } - /* the last two parameters will only be used for level == 0 */ - ret = add_all_parents(root, path, parents, eb, level, key.objectid, - ref->wanted_disk_byte); + ret = add_all_parents(root, path, parents, ref, level, time_seq, + extent_item_pos, total_refs); out: - btrfs_free_path(path); + path->lowest_level = 0; + btrfs_release_path(path); return ret; } @@ -188,7 +376,9 @@ out: * resolve all indirect backrefs from the list */ static int __resolve_indirect_refs(struct btrfs_fs_info *fs_info, - struct list_head *head) + struct btrfs_path *path, u64 time_seq, + struct list_head *head, + const u64 *extent_item_pos, u64 total_refs) { int err; int ret = 0; @@ -197,6 +387,7 @@ static int __resolve_indirect_refs(struct btrfs_fs_info *fs_info, struct __prelim_ref *new_ref; struct ulist *parents; struct ulist_node *node; + struct ulist_iterator uiter; parents = ulist_alloc(GFP_NOFS); if (!parents) @@ -212,42 +403,113 @@ static int __resolve_indirect_refs(struct btrfs_fs_info *fs_info, continue; if (ref->count == 0) continue; - err = __resolve_indirect_ref(fs_info, ref, parents); - if (err) { - if (ret == 0) - ret = err; + err = __resolve_indirect_ref(fs_info, path, time_seq, ref, + parents, extent_item_pos, + total_refs); + /* + * we can only tolerate ENOENT,otherwise,we should catch error + * and return directly. + */ + if (err == -ENOENT) { continue; + } else if (err) { + ret = err; + goto out; } /* we put the first parent into the ref at hand */ - node = ulist_next(parents, NULL); + ULIST_ITER_INIT(&uiter); + node = ulist_next(parents, &uiter); ref->parent = node ? node->val : 0; + ref->inode_list = node ? + (struct extent_inode_elem *)(uintptr_t)node->aux : NULL; /* additional parents require new refs being added here */ - while ((node = ulist_next(parents, node))) { - new_ref = kmalloc(sizeof(*new_ref), GFP_NOFS); + while ((node = ulist_next(parents, &uiter))) { + new_ref = kmem_cache_alloc(btrfs_prelim_ref_cache, + GFP_NOFS); if (!new_ref) { ret = -ENOMEM; - break; + goto out; } memcpy(new_ref, ref, sizeof(*ref)); new_ref->parent = node->val; + new_ref->inode_list = (struct extent_inode_elem *) + (uintptr_t)node->aux; list_add(&new_ref->list, &ref->list); } ulist_reinit(parents); } - +out: ulist_free(parents); return ret; } +static inline int ref_for_same_block(struct __prelim_ref *ref1, + struct __prelim_ref *ref2) +{ + if (ref1->level != ref2->level) + return 0; + if (ref1->root_id != ref2->root_id) + return 0; + if (ref1->key_for_search.type != ref2->key_for_search.type) + return 0; + if (ref1->key_for_search.objectid != ref2->key_for_search.objectid) + return 0; + if (ref1->key_for_search.offset != ref2->key_for_search.offset) + return 0; + if (ref1->parent != ref2->parent) + return 0; + + return 1; +} + +/* + * read tree blocks and add keys where required. + */ +static int __add_missing_keys(struct btrfs_fs_info *fs_info, + struct list_head *head) +{ + struct list_head *pos; + struct extent_buffer *eb; + + list_for_each(pos, head) { + struct __prelim_ref *ref; + ref = list_entry(pos, struct __prelim_ref, list); + + if (ref->parent) + continue; + if (ref->key_for_search.type) + continue; + BUG_ON(!ref->wanted_disk_byte); + eb = read_tree_block(fs_info->tree_root, ref->wanted_disk_byte, + fs_info->tree_root->leafsize, 0); + if (!eb || !extent_buffer_uptodate(eb)) { + free_extent_buffer(eb); + return -EIO; + } + btrfs_tree_read_lock(eb); + if (btrfs_header_level(eb) == 0) + btrfs_item_key_to_cpu(eb, &ref->key_for_search, 0); + else + btrfs_node_key_to_cpu(eb, &ref->key_for_search, 0); + btrfs_tree_read_unlock(eb); + free_extent_buffer(eb); + } + return 0; +} + /* * merge two lists of backrefs and adjust counts accordingly * * mode = 1: merge identical keys, if key is set + * FIXME: if we add more keys in __add_prelim_ref, we can merge more here. + * additionally, we could even add a key range for the blocks we + * looked into to merge even more (-> replace unresolved refs by those + * having a parent). * mode = 2: merge identical parents */ -static int __merge_refs(struct list_head *head, int mode) +static void __merge_refs(struct list_head *head, int mode) { struct list_head *pos1; @@ -258,32 +520,41 @@ static int __merge_refs(struct list_head *head, int mode) ref1 = list_entry(pos1, struct __prelim_ref, list); - if (mode == 1 && ref1->key.type == 0) - continue; for (pos2 = pos1->next, n2 = pos2->next; pos2 != head; pos2 = n2, n2 = pos2->next) { struct __prelim_ref *ref2; + struct __prelim_ref *xchg; + struct extent_inode_elem *eie; ref2 = list_entry(pos2, struct __prelim_ref, list); if (mode == 1) { - if (memcmp(&ref1->key, &ref2->key, - sizeof(ref1->key)) || - ref1->level != ref2->level || - ref1->root_id != ref2->root_id) + if (!ref_for_same_block(ref1, ref2)) continue; - ref1->count += ref2->count; + if (!ref1->parent && ref2->parent) { + xchg = ref1; + ref1 = ref2; + ref2 = xchg; + } } else { if (ref1->parent != ref2->parent) continue; - ref1->count += ref2->count; } + + eie = ref1->inode_list; + while (eie && eie->next) + eie = eie->next; + if (eie) + eie->next = ref2->inode_list; + else + ref1->inode_list = ref2->inode_list; + ref1->count += ref2->count; + list_del(&ref2->list); - kfree(ref2); + kmem_cache_free(btrfs_prelim_ref_cache, ref2); } } - return 0; } /* @@ -291,25 +562,25 @@ static int __merge_refs(struct list_head *head, int mode) * smaller or equal that seq to the list */ static int __add_delayed_refs(struct btrfs_delayed_ref_head *head, u64 seq, - struct btrfs_key *info_key, - struct list_head *prefs) + struct list_head *prefs, u64 *total_refs) { struct btrfs_delayed_extent_op *extent_op = head->extent_op; struct rb_node *n = &head->node.rb_node; + struct btrfs_key key; + struct btrfs_key op_key = {0}; int sgn; int ret = 0; if (extent_op && extent_op->update_key) - btrfs_disk_key_to_cpu(info_key, &extent_op->key); + btrfs_disk_key_to_cpu(&op_key, &extent_op->key); - while ((n = rb_prev(n))) { + spin_lock(&head->lock); + n = rb_first(&head->ref_root); + while (n) { struct btrfs_delayed_ref_node *node; node = rb_entry(n, struct btrfs_delayed_ref_node, rb_node); - if (node->bytenr != head->node.bytenr) - break; - WARN_ON(node->is_head); - + n = rb_next(n); if (node->seq > seq) continue; @@ -327,30 +598,29 @@ static int __add_delayed_refs(struct btrfs_delayed_ref_head *head, u64 seq, default: BUG_ON(1); } + *total_refs += (node->ref_mod * sgn); switch (node->type) { case BTRFS_TREE_BLOCK_REF_KEY: { struct btrfs_delayed_tree_ref *ref; ref = btrfs_delayed_node_to_tree_ref(node); - ret = __add_prelim_ref(prefs, ref->root, info_key, + ret = __add_prelim_ref(prefs, ref->root, &op_key, ref->level + 1, 0, node->bytenr, - node->ref_mod * sgn); + node->ref_mod * sgn, GFP_ATOMIC); break; } case BTRFS_SHARED_BLOCK_REF_KEY: { struct btrfs_delayed_tree_ref *ref; ref = btrfs_delayed_node_to_tree_ref(node); - ret = __add_prelim_ref(prefs, ref->root, info_key, + ret = __add_prelim_ref(prefs, ref->root, NULL, ref->level + 1, ref->parent, node->bytenr, - node->ref_mod * sgn); + node->ref_mod * sgn, GFP_ATOMIC); break; } case BTRFS_EXTENT_DATA_REF_KEY: { struct btrfs_delayed_data_ref *ref; - struct btrfs_key key; - ref = btrfs_delayed_node_to_data_ref(node); key.objectid = ref->objectid; @@ -358,12 +628,11 @@ static int __add_delayed_refs(struct btrfs_delayed_ref_head *head, u64 seq, key.offset = ref->offset; ret = __add_prelim_ref(prefs, ref->root, &key, 0, 0, node->bytenr, - node->ref_mod * sgn); + node->ref_mod * sgn, GFP_ATOMIC); break; } case BTRFS_SHARED_DATA_REF_KEY: { struct btrfs_delayed_data_ref *ref; - struct btrfs_key key; ref = btrfs_delayed_node_to_data_ref(node); @@ -372,16 +641,17 @@ static int __add_delayed_refs(struct btrfs_delayed_ref_head *head, u64 seq, key.offset = ref->offset; ret = __add_prelim_ref(prefs, ref->root, &key, 0, ref->parent, node->bytenr, - node->ref_mod * sgn); + node->ref_mod * sgn, GFP_ATOMIC); break; } default: WARN_ON(1); } - BUG_ON(ret); + if (ret) + break; } - - return 0; + spin_unlock(&head->lock); + return ret; } /* @@ -389,13 +659,14 @@ static int __add_delayed_refs(struct btrfs_delayed_ref_head *head, u64 seq, */ static int __add_inline_refs(struct btrfs_fs_info *fs_info, struct btrfs_path *path, u64 bytenr, - struct btrfs_key *info_key, int *info_level, - struct list_head *prefs) + int *info_level, struct list_head *prefs, + u64 *total_refs) { int ret = 0; int slot; struct extent_buffer *leaf; struct btrfs_key key; + struct btrfs_key found_key; unsigned long ptr; unsigned long end; struct btrfs_extent_item *ei; @@ -406,27 +677,29 @@ static int __add_inline_refs(struct btrfs_fs_info *fs_info, * enumerate all inline refs */ leaf = path->nodes[0]; - slot = path->slots[0] - 1; + slot = path->slots[0]; item_size = btrfs_item_size_nr(leaf, slot); BUG_ON(item_size < sizeof(*ei)); ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item); flags = btrfs_extent_flags(leaf, ei); + *total_refs += btrfs_extent_refs(leaf, ei); + btrfs_item_key_to_cpu(leaf, &found_key, slot); ptr = (unsigned long)(ei + 1); end = (unsigned long)ei + item_size; - if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { + if (found_key.type == BTRFS_EXTENT_ITEM_KEY && + flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { struct btrfs_tree_block_info *info; - struct btrfs_disk_key disk_key; info = (struct btrfs_tree_block_info *)ptr; *info_level = btrfs_tree_block_level(leaf, info); - btrfs_tree_block_key(leaf, info, &disk_key); - btrfs_disk_key_to_cpu(info_key, &disk_key); ptr += sizeof(struct btrfs_tree_block_info); BUG_ON(ptr > end); + } else if (found_key.type == BTRFS_METADATA_ITEM_KEY) { + *info_level = found_key.offset; } else { BUG_ON(!(flags & BTRFS_EXTENT_FLAG_DATA)); } @@ -442,9 +715,9 @@ static int __add_inline_refs(struct btrfs_fs_info *fs_info, switch (type) { case BTRFS_SHARED_BLOCK_REF_KEY: - ret = __add_prelim_ref(prefs, 0, info_key, + ret = __add_prelim_ref(prefs, 0, NULL, *info_level + 1, offset, - bytenr, 1); + bytenr, 1, GFP_NOFS); break; case BTRFS_SHARED_DATA_REF_KEY: { struct btrfs_shared_data_ref *sdref; @@ -453,12 +726,13 @@ static int __add_inline_refs(struct btrfs_fs_info *fs_info, sdref = (struct btrfs_shared_data_ref *)(iref + 1); count = btrfs_shared_data_ref_count(leaf, sdref); ret = __add_prelim_ref(prefs, 0, NULL, 0, offset, - bytenr, count); + bytenr, count, GFP_NOFS); break; } case BTRFS_TREE_BLOCK_REF_KEY: - ret = __add_prelim_ref(prefs, offset, info_key, - *info_level + 1, 0, bytenr, 1); + ret = __add_prelim_ref(prefs, offset, NULL, + *info_level + 1, 0, + bytenr, 1, GFP_NOFS); break; case BTRFS_EXTENT_DATA_REF_KEY: { struct btrfs_extent_data_ref *dref; @@ -472,14 +746,15 @@ static int __add_inline_refs(struct btrfs_fs_info *fs_info, key.type = BTRFS_EXTENT_DATA_KEY; key.offset = btrfs_extent_data_ref_offset(leaf, dref); root = btrfs_extent_data_ref_root(leaf, dref); - ret = __add_prelim_ref(prefs, root, &key, 0, 0, bytenr, - count); + ret = __add_prelim_ref(prefs, root, &key, 0, 0, + bytenr, count, GFP_NOFS); break; } default: WARN_ON(1); } - BUG_ON(ret); + if (ret) + return ret; ptr += btrfs_extent_inline_ref_size(type); } @@ -491,8 +766,7 @@ static int __add_inline_refs(struct btrfs_fs_info *fs_info, */ static int __add_keyed_refs(struct btrfs_fs_info *fs_info, struct btrfs_path *path, u64 bytenr, - struct btrfs_key *info_key, int info_level, - struct list_head *prefs) + int info_level, struct list_head *prefs) { struct btrfs_root *extent_root = fs_info->extent_root; int ret; @@ -522,9 +796,9 @@ static int __add_keyed_refs(struct btrfs_fs_info *fs_info, switch (key.type) { case BTRFS_SHARED_BLOCK_REF_KEY: - ret = __add_prelim_ref(prefs, 0, info_key, + ret = __add_prelim_ref(prefs, 0, NULL, info_level + 1, key.offset, - bytenr, 1); + bytenr, 1, GFP_NOFS); break; case BTRFS_SHARED_DATA_REF_KEY: { struct btrfs_shared_data_ref *sdref; @@ -534,12 +808,13 @@ static int __add_keyed_refs(struct btrfs_fs_info *fs_info, struct btrfs_shared_data_ref); count = btrfs_shared_data_ref_count(leaf, sdref); ret = __add_prelim_ref(prefs, 0, NULL, 0, key.offset, - bytenr, count); + bytenr, count, GFP_NOFS); break; } case BTRFS_TREE_BLOCK_REF_KEY: - ret = __add_prelim_ref(prefs, key.offset, info_key, - info_level + 1, 0, bytenr, 1); + ret = __add_prelim_ref(prefs, key.offset, NULL, + info_level + 1, 0, + bytenr, 1, GFP_NOFS); break; case BTRFS_EXTENT_DATA_REF_KEY: { struct btrfs_extent_data_ref *dref; @@ -555,13 +830,15 @@ static int __add_keyed_refs(struct btrfs_fs_info *fs_info, key.offset = btrfs_extent_data_ref_offset(leaf, dref); root = btrfs_extent_data_ref_root(leaf, dref); ret = __add_prelim_ref(prefs, root, &key, 0, 0, - bytenr, count); + bytenr, count, GFP_NOFS); break; } default: WARN_ON(1); } - BUG_ON(ret); + if (ret) + return ret; + } return ret; @@ -577,29 +854,38 @@ static int __add_keyed_refs(struct btrfs_fs_info *fs_info, */ static int find_parent_nodes(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info, u64 bytenr, - u64 seq, struct ulist *refs, struct ulist *roots) + u64 time_seq, struct ulist *refs, + struct ulist *roots, const u64 *extent_item_pos) { struct btrfs_key key; struct btrfs_path *path; - struct btrfs_key info_key = { 0 }; struct btrfs_delayed_ref_root *delayed_refs = NULL; - struct btrfs_delayed_ref_head *head = NULL; + struct btrfs_delayed_ref_head *head; int info_level = 0; int ret; struct list_head prefs_delayed; struct list_head prefs; struct __prelim_ref *ref; + struct extent_inode_elem *eie = NULL; + u64 total_refs = 0; INIT_LIST_HEAD(&prefs); INIT_LIST_HEAD(&prefs_delayed); key.objectid = bytenr; - key.type = BTRFS_EXTENT_ITEM_KEY; key.offset = (u64)-1; + if (btrfs_fs_incompat(fs_info, SKINNY_METADATA)) + key.type = BTRFS_METADATA_ITEM_KEY; + else + key.type = BTRFS_EXTENT_ITEM_KEY; path = btrfs_alloc_path(); if (!path) return -ENOMEM; + if (!trans) { + path->search_commit_root = 1; + path->skip_locking = 1; + } /* * grab both a lock on the path and a lock on the delayed ref head. @@ -607,53 +893,69 @@ static int find_parent_nodes(struct btrfs_trans_handle *trans, * at a specified point in time */ again: + head = NULL; + ret = btrfs_search_slot(trans, fs_info->extent_root, &key, path, 0, 0); if (ret < 0) goto out; BUG_ON(ret == 0); - /* - * look if there are updates for this ref queued and lock the head - */ - delayed_refs = &trans->transaction->delayed_refs; - spin_lock(&delayed_refs->lock); - head = btrfs_find_delayed_ref_head(trans, bytenr); - if (head) { - if (!mutex_trylock(&head->mutex)) { - atomic_inc(&head->node.refs); +#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS + if (trans && likely(trans->type != __TRANS_DUMMY)) { +#else + if (trans) { +#endif + /* + * look if there are updates for this ref queued and lock the + * head + */ + delayed_refs = &trans->transaction->delayed_refs; + spin_lock(&delayed_refs->lock); + head = btrfs_find_delayed_ref_head(trans, bytenr); + if (head) { + if (!mutex_trylock(&head->mutex)) { + atomic_inc(&head->node.refs); + spin_unlock(&delayed_refs->lock); + + btrfs_release_path(path); + + /* + * Mutex was contended, block until it's + * released and try again + */ + mutex_lock(&head->mutex); + mutex_unlock(&head->mutex); + btrfs_put_delayed_ref(&head->node); + goto again; + } spin_unlock(&delayed_refs->lock); - - btrfs_release_path(path); - - /* - * Mutex was contended, block until it's - * released and try again - */ - mutex_lock(&head->mutex); + ret = __add_delayed_refs(head, time_seq, + &prefs_delayed, &total_refs); mutex_unlock(&head->mutex); - btrfs_put_delayed_ref(&head->node); - goto again; + if (ret) + goto out; + } else { + spin_unlock(&delayed_refs->lock); } - ret = __add_delayed_refs(head, seq, &info_key, &prefs_delayed); - if (ret) - goto out; } - spin_unlock(&delayed_refs->lock); if (path->slots[0]) { struct extent_buffer *leaf; int slot; + path->slots[0]--; leaf = path->nodes[0]; - slot = path->slots[0] - 1; + slot = path->slots[0]; btrfs_item_key_to_cpu(leaf, &key, slot); if (key.objectid == bytenr && - key.type == BTRFS_EXTENT_ITEM_KEY) { + (key.type == BTRFS_EXTENT_ITEM_KEY || + key.type == BTRFS_METADATA_ITEM_KEY)) { ret = __add_inline_refs(fs_info, path, bytenr, - &info_key, &info_level, &prefs); + &info_level, &prefs, + &total_refs); if (ret) goto out; - ret = __add_keyed_refs(fs_info, path, bytenr, &info_key, + ret = __add_keyed_refs(fs_info, path, bytenr, info_level, &prefs); if (ret) goto out; @@ -661,64 +963,108 @@ again: } btrfs_release_path(path); - /* - * when adding the delayed refs above, the info_key might not have - * been known yet. Go over the list and replace the missing keys - */ - list_for_each_entry(ref, &prefs_delayed, list) { - if ((ref->key.offset | ref->key.type | ref->key.objectid) == 0) - memcpy(&ref->key, &info_key, sizeof(ref->key)); - } list_splice_init(&prefs_delayed, &prefs); - ret = __merge_refs(&prefs, 1); + ret = __add_missing_keys(fs_info, &prefs); if (ret) goto out; - ret = __resolve_indirect_refs(fs_info, &prefs); - if (ret) - goto out; + __merge_refs(&prefs, 1); - ret = __merge_refs(&prefs, 2); + ret = __resolve_indirect_refs(fs_info, path, time_seq, &prefs, + extent_item_pos, total_refs); if (ret) goto out; + __merge_refs(&prefs, 2); + while (!list_empty(&prefs)) { ref = list_first_entry(&prefs, struct __prelim_ref, list); - list_del(&ref->list); - if (ref->count < 0) - WARN_ON(1); - if (ref->count && ref->root_id && ref->parent == 0) { + WARN_ON(ref->count < 0); + if (roots && ref->count && ref->root_id && ref->parent == 0) { /* no parent == root of tree */ ret = ulist_add(roots, ref->root_id, 0, GFP_NOFS); - BUG_ON(ret < 0); + if (ret < 0) + goto out; } if (ref->count && ref->parent) { - ret = ulist_add(refs, ref->parent, 0, GFP_NOFS); - BUG_ON(ret < 0); + if (extent_item_pos && !ref->inode_list && + ref->level == 0) { + u32 bsz; + struct extent_buffer *eb; + bsz = btrfs_level_size(fs_info->extent_root, + ref->level); + eb = read_tree_block(fs_info->extent_root, + ref->parent, bsz, 0); + if (!eb || !extent_buffer_uptodate(eb)) { + free_extent_buffer(eb); + ret = -EIO; + goto out; + } + ret = find_extent_in_eb(eb, bytenr, + *extent_item_pos, &eie); + free_extent_buffer(eb); + if (ret < 0) + goto out; + ref->inode_list = eie; + } + ret = ulist_add_merge(refs, ref->parent, + (uintptr_t)ref->inode_list, + (u64 *)&eie, GFP_NOFS); + if (ret < 0) + goto out; + if (!ret && extent_item_pos) { + /* + * we've recorded that parent, so we must extend + * its inode list here + */ + BUG_ON(!eie); + while (eie->next) + eie = eie->next; + eie->next = ref->inode_list; + } + eie = NULL; } - kfree(ref); + list_del(&ref->list); + kmem_cache_free(btrfs_prelim_ref_cache, ref); } out: - if (head) - mutex_unlock(&head->mutex); btrfs_free_path(path); while (!list_empty(&prefs)) { ref = list_first_entry(&prefs, struct __prelim_ref, list); list_del(&ref->list); - kfree(ref); + kmem_cache_free(btrfs_prelim_ref_cache, ref); } while (!list_empty(&prefs_delayed)) { ref = list_first_entry(&prefs_delayed, struct __prelim_ref, list); list_del(&ref->list); - kfree(ref); + kmem_cache_free(btrfs_prelim_ref_cache, ref); } - + if (ret < 0) + free_inode_elem_list(eie); return ret; } +static void free_leaf_list(struct ulist *blocks) +{ + struct ulist_node *node = NULL; + struct extent_inode_elem *eie; + struct ulist_iterator uiter; + + ULIST_ITER_INIT(&uiter); + while ((node = ulist_next(blocks, &uiter))) { + if (!node->aux) + continue; + eie = (struct extent_inode_elem *)(uintptr_t)node->aux; + free_inode_elem_list(eie); + node->aux = 0; + } + + ulist_free(blocks); +} + /* * Finds all leafs with a reference to the specified combination of bytenr and * offset. key_list_head will point to a list of corresponding keys (caller must @@ -729,25 +1075,19 @@ out: */ static int btrfs_find_all_leafs(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info, u64 bytenr, - u64 num_bytes, u64 seq, struct ulist **leafs) + u64 time_seq, struct ulist **leafs, + const u64 *extent_item_pos) { - struct ulist *tmp; int ret; - tmp = ulist_alloc(GFP_NOFS); - if (!tmp) - return -ENOMEM; *leafs = ulist_alloc(GFP_NOFS); - if (!*leafs) { - ulist_free(tmp); + if (!*leafs) return -ENOMEM; - } - - ret = find_parent_nodes(trans, fs_info, bytenr, seq, *leafs, tmp); - ulist_free(tmp); + ret = find_parent_nodes(trans, fs_info, bytenr, + time_seq, *leafs, NULL, extent_item_pos); if (ret < 0 && ret != -ENOENT) { - ulist_free(*leafs); + free_leaf_list(*leafs); return ret; } @@ -767,12 +1107,13 @@ static int btrfs_find_all_leafs(struct btrfs_trans_handle *trans, * * returns 0 on success, < 0 on error. */ -int btrfs_find_all_roots(struct btrfs_trans_handle *trans, - struct btrfs_fs_info *fs_info, u64 bytenr, - u64 num_bytes, u64 seq, struct ulist **roots) +static int __btrfs_find_all_roots(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, u64 bytenr, + u64 time_seq, struct ulist **roots) { struct ulist *tmp; struct ulist_node *node = NULL; + struct ulist_iterator uiter; int ret; tmp = ulist_alloc(GFP_NOFS); @@ -784,54 +1125,38 @@ int btrfs_find_all_roots(struct btrfs_trans_handle *trans, return -ENOMEM; } + ULIST_ITER_INIT(&uiter); while (1) { - ret = find_parent_nodes(trans, fs_info, bytenr, seq, - tmp, *roots); + ret = find_parent_nodes(trans, fs_info, bytenr, + time_seq, tmp, *roots, NULL); if (ret < 0 && ret != -ENOENT) { ulist_free(tmp); ulist_free(*roots); return ret; } - node = ulist_next(tmp, node); + node = ulist_next(tmp, &uiter); if (!node) break; bytenr = node->val; + cond_resched(); } ulist_free(tmp); return 0; } - -static int __inode_info(u64 inum, u64 ioff, u8 key_type, - struct btrfs_root *fs_root, struct btrfs_path *path, - struct btrfs_key *found_key) +int btrfs_find_all_roots(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, u64 bytenr, + u64 time_seq, struct ulist **roots) { int ret; - struct btrfs_key key; - struct extent_buffer *eb; - - key.type = key_type; - key.objectid = inum; - key.offset = ioff; - - ret = btrfs_search_slot(NULL, fs_root, &key, path, 0, 0); - if (ret < 0) - return ret; - - eb = path->nodes[0]; - if (ret && path->slots[0] >= btrfs_header_nritems(eb)) { - ret = btrfs_next_leaf(fs_root, path); - if (ret) - return ret; - eb = path->nodes[0]; - } - - btrfs_item_key_to_cpu(eb, found_key, path->slots[0]); - if (found_key->type != key.type || found_key->objectid != key.objectid) - return 1; - return 0; + if (!trans) + down_read(&fs_info->commit_root_sem); + ret = __btrfs_find_all_roots(trans, fs_info, bytenr, time_seq, roots); + if (!trans) + up_read(&fs_info->commit_root_sem); + return ret; } /* @@ -841,21 +1166,89 @@ int inode_item_info(u64 inum, u64 ioff, struct btrfs_root *fs_root, struct btrfs_path *path) { struct btrfs_key key; - return __inode_info(inum, ioff, BTRFS_INODE_ITEM_KEY, fs_root, path, - &key); + return btrfs_find_item(fs_root, path, inum, ioff, + BTRFS_INODE_ITEM_KEY, &key); } static int inode_ref_info(u64 inum, u64 ioff, struct btrfs_root *fs_root, struct btrfs_path *path, struct btrfs_key *found_key) { - return __inode_info(inum, ioff, BTRFS_INODE_REF_KEY, fs_root, path, - found_key); + return btrfs_find_item(fs_root, path, inum, ioff, + BTRFS_INODE_REF_KEY, found_key); +} + +int btrfs_find_one_extref(struct btrfs_root *root, u64 inode_objectid, + u64 start_off, struct btrfs_path *path, + struct btrfs_inode_extref **ret_extref, + u64 *found_off) +{ + int ret, slot; + struct btrfs_key key; + struct btrfs_key found_key; + struct btrfs_inode_extref *extref; + struct extent_buffer *leaf; + unsigned long ptr; + + key.objectid = inode_objectid; + btrfs_set_key_type(&key, BTRFS_INODE_EXTREF_KEY); + key.offset = start_off; + + ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + if (ret < 0) + return ret; + + while (1) { + leaf = path->nodes[0]; + slot = path->slots[0]; + if (slot >= btrfs_header_nritems(leaf)) { + /* + * If the item at offset is not found, + * btrfs_search_slot will point us to the slot + * where it should be inserted. In our case + * that will be the slot directly before the + * next INODE_REF_KEY_V2 item. In the case + * that we're pointing to the last slot in a + * leaf, we must move one leaf over. + */ + ret = btrfs_next_leaf(root, path); + if (ret) { + if (ret >= 1) + ret = -ENOENT; + break; + } + continue; + } + + btrfs_item_key_to_cpu(leaf, &found_key, slot); + + /* + * Check that we're still looking at an extended ref key for + * this particular objectid. If we have different + * objectid or type then there are no more to be found + * in the tree and we can exit. + */ + ret = -ENOENT; + if (found_key.objectid != inode_objectid) + break; + if (btrfs_key_type(&found_key) != BTRFS_INODE_EXTREF_KEY) + break; + + ret = 0; + ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); + extref = (struct btrfs_inode_extref *)ptr; + *ret_extref = extref; + if (found_off) + *found_off = found_key.offset; + break; + } + + return ret; } /* - * this iterates to turn a btrfs_inode_ref into a full filesystem path. elements - * of the path are separated by '/' and the path is guaranteed to be + * this iterates to turn a name (from iref/extref) into a full filesystem path. + * Elements of the path are separated by '/' and the path is guaranteed to be * 0-terminated. the path is only given within the current file system. * Therefore, it never starts with a '/'. the caller is responsible to provide * "size" bytes in "dest". the dest buffer will be filled backwards. finally, @@ -867,33 +1260,39 @@ static int inode_ref_info(u64 inum, u64 ioff, struct btrfs_root *fs_root, * required for the path to fit into the buffer. in that case, the returned * value will be smaller than dest. callers must check this! */ -static char *iref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path, - struct btrfs_inode_ref *iref, - struct extent_buffer *eb_in, u64 parent, - char *dest, u32 size) +char *btrfs_ref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path, + u32 name_len, unsigned long name_off, + struct extent_buffer *eb_in, u64 parent, + char *dest, u32 size) { - u32 len; int slot; u64 next_inum; int ret; - s64 bytes_left = size - 1; + s64 bytes_left = ((s64)size) - 1; struct extent_buffer *eb = eb_in; struct btrfs_key found_key; + int leave_spinning = path->leave_spinning; + struct btrfs_inode_ref *iref; if (bytes_left >= 0) dest[bytes_left] = '\0'; + path->leave_spinning = 1; while (1) { - len = btrfs_inode_ref_name_len(eb, iref); - bytes_left -= len; + bytes_left -= name_len; if (bytes_left >= 0) read_extent_buffer(eb, dest + bytes_left, - (unsigned long)(iref + 1), len); - if (eb != eb_in) + name_off, name_len); + if (eb != eb_in) { + btrfs_tree_read_unlock_blocking(eb); free_extent_buffer(eb); + } ret = inode_ref_info(parent, 0, fs_root, path, &found_key); + if (ret > 0) + ret = -ENOENT; if (ret) break; + next_inum = found_key.offset; /* regular exit ahead */ @@ -903,11 +1302,17 @@ static char *iref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path, slot = path->slots[0]; eb = path->nodes[0]; /* make sure we can use eb after releasing the path */ - if (eb != eb_in) + if (eb != eb_in) { atomic_inc(&eb->refs); + btrfs_tree_read_lock(eb); + btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK); + } btrfs_release_path(path); - iref = btrfs_item_ptr(eb, slot, struct btrfs_inode_ref); + + name_len = btrfs_inode_ref_name_len(eb, iref); + name_off = (unsigned long)(iref + 1); + parent = next_inum; --bytes_left; if (bytes_left >= 0) @@ -915,6 +1320,7 @@ static char *iref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path, } btrfs_release_path(path); + path->leave_spinning = leave_spinning; if (ret) return ERR_PTR(ret); @@ -928,33 +1334,43 @@ static char *iref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path, * tree blocks and <0 on error. */ int extent_from_logical(struct btrfs_fs_info *fs_info, u64 logical, - struct btrfs_path *path, struct btrfs_key *found_key) + struct btrfs_path *path, struct btrfs_key *found_key, + u64 *flags_ret) { int ret; u64 flags; + u64 size = 0; u32 item_size; struct extent_buffer *eb; struct btrfs_extent_item *ei; struct btrfs_key key; - key.type = BTRFS_EXTENT_ITEM_KEY; + if (btrfs_fs_incompat(fs_info, SKINNY_METADATA)) + key.type = BTRFS_METADATA_ITEM_KEY; + else + key.type = BTRFS_EXTENT_ITEM_KEY; key.objectid = logical; key.offset = (u64)-1; ret = btrfs_search_slot(NULL, fs_info->extent_root, &key, path, 0, 0); if (ret < 0) return ret; - ret = btrfs_previous_item(fs_info->extent_root, path, - 0, BTRFS_EXTENT_ITEM_KEY); - if (ret < 0) - return ret; + ret = btrfs_previous_extent_item(fs_info->extent_root, path, 0); + if (ret) { + if (ret > 0) + ret = -ENOENT; + return ret; + } btrfs_item_key_to_cpu(path->nodes[0], found_key, path->slots[0]); - if (found_key->type != BTRFS_EXTENT_ITEM_KEY || - found_key->objectid > logical || - found_key->objectid + found_key->offset <= logical) { - pr_debug("logical %llu is not within any extent\n", - (unsigned long long)logical); + if (found_key->type == BTRFS_METADATA_ITEM_KEY) + size = fs_info->extent_root->leafsize; + else if (found_key->type == BTRFS_EXTENT_ITEM_KEY) + size = found_key->offset; + + if (found_key->objectid > logical || + found_key->objectid + size <= logical) { + pr_debug("logical %llu is not within any extent\n", logical); return -ENOENT; } @@ -967,15 +1383,19 @@ int extent_from_logical(struct btrfs_fs_info *fs_info, u64 logical, pr_debug("logical %llu is at position %llu within the extent (%llu " "EXTENT_ITEM %llu) flags %#llx size %u\n", - (unsigned long long)logical, - (unsigned long long)(logical - found_key->objectid), - (unsigned long long)found_key->objectid, - (unsigned long long)found_key->offset, - (unsigned long long)flags, item_size); - if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) - return BTRFS_EXTENT_FLAG_TREE_BLOCK; - if (flags & BTRFS_EXTENT_FLAG_DATA) - return BTRFS_EXTENT_FLAG_DATA; + logical, logical - found_key->objectid, found_key->objectid, + found_key->offset, flags, item_size); + + WARN_ON(!flags_ret); + if (flags_ret) { + if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) + *flags_ret = BTRFS_EXTENT_FLAG_TREE_BLOCK; + else if (flags & BTRFS_EXTENT_FLAG_DATA) + *flags_ret = BTRFS_EXTENT_FLAG_DATA; + else + BUG_ON(1); + return 0; + } return -EIO; } @@ -989,9 +1409,10 @@ int extent_from_logical(struct btrfs_fs_info *fs_info, u64 logical, * returns <0 on error */ static int __get_extent_inline_ref(unsigned long *ptr, struct extent_buffer *eb, - struct btrfs_extent_item *ei, u32 item_size, - struct btrfs_extent_inline_ref **out_eiref, - int *out_type) + struct btrfs_key *key, + struct btrfs_extent_item *ei, u32 item_size, + struct btrfs_extent_inline_ref **out_eiref, + int *out_type) { unsigned long end; u64 flags; @@ -1001,19 +1422,26 @@ static int __get_extent_inline_ref(unsigned long *ptr, struct extent_buffer *eb, /* first call */ flags = btrfs_extent_flags(eb, ei); if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { - info = (struct btrfs_tree_block_info *)(ei + 1); - *out_eiref = - (struct btrfs_extent_inline_ref *)(info + 1); + if (key->type == BTRFS_METADATA_ITEM_KEY) { + /* a skinny metadata extent */ + *out_eiref = + (struct btrfs_extent_inline_ref *)(ei + 1); + } else { + WARN_ON(key->type != BTRFS_EXTENT_ITEM_KEY); + info = (struct btrfs_tree_block_info *)(ei + 1); + *out_eiref = + (struct btrfs_extent_inline_ref *)(info + 1); + } } else { *out_eiref = (struct btrfs_extent_inline_ref *)(ei + 1); } *ptr = (unsigned long)*out_eiref; - if ((void *)*ptr >= (void *)ei + item_size) + if ((unsigned long)(*ptr) >= (unsigned long)ei + item_size) return -ENOENT; } end = (unsigned long)ei + item_size; - *out_eiref = (struct btrfs_extent_inline_ref *)*ptr; + *out_eiref = (struct btrfs_extent_inline_ref *)(*ptr); *out_type = btrfs_extent_inline_ref_type(eb, *out_eiref); *ptr += btrfs_extent_inline_ref_size(*out_type); @@ -1032,8 +1460,8 @@ static int __get_extent_inline_ref(unsigned long *ptr, struct extent_buffer *eb, * <0 on error. */ int tree_backref_for_extent(unsigned long *ptr, struct extent_buffer *eb, - struct btrfs_extent_item *ei, u32 item_size, - u64 *out_root, u8 *out_level) + struct btrfs_key *key, struct btrfs_extent_item *ei, + u32 item_size, u64 *out_root, u8 *out_level) { int ret; int type; @@ -1044,8 +1472,8 @@ int tree_backref_for_extent(unsigned long *ptr, struct extent_buffer *eb, return 1; while (1) { - ret = __get_extent_inline_ref(ptr, eb, ei, item_size, - &eiref, &type); + ret = __get_extent_inline_ref(ptr, eb, key, ei, item_size, + &eiref, &type); if (ret < 0) return ret; @@ -1068,68 +1496,25 @@ int tree_backref_for_extent(unsigned long *ptr, struct extent_buffer *eb, return 0; } -static int iterate_leaf_refs(struct btrfs_fs_info *fs_info, - struct btrfs_path *path, u64 logical, - u64 orig_extent_item_objectid, - u64 extent_item_pos, u64 root, +static int iterate_leaf_refs(struct extent_inode_elem *inode_list, + u64 root, u64 extent_item_objectid, iterate_extent_inodes_t *iterate, void *ctx) { - u64 disk_byte; - struct btrfs_key key; - struct btrfs_file_extent_item *fi; - struct extent_buffer *eb; - int slot; - int nritems; + struct extent_inode_elem *eie; int ret = 0; - int extent_type; - u64 data_offset; - u64 data_len; - - eb = read_tree_block(fs_info->tree_root, logical, - fs_info->tree_root->leafsize, 0); - if (!eb) - return -EIO; - - /* - * from the shared data ref, we only have the leaf but we need - * the key. thus, we must look into all items and see that we - * find one (some) with a reference to our extent item. - */ - nritems = btrfs_header_nritems(eb); - for (slot = 0; slot < nritems; ++slot) { - btrfs_item_key_to_cpu(eb, &key, slot); - if (key.type != BTRFS_EXTENT_DATA_KEY) - continue; - fi = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item); - extent_type = btrfs_file_extent_type(eb, fi); - if (extent_type == BTRFS_FILE_EXTENT_INLINE) - continue; - /* don't skip BTRFS_FILE_EXTENT_PREALLOC, we can handle that */ - disk_byte = btrfs_file_extent_disk_bytenr(eb, fi); - if (disk_byte != orig_extent_item_objectid) - continue; - - data_offset = btrfs_file_extent_offset(eb, fi); - data_len = btrfs_file_extent_num_bytes(eb, fi); - - if (extent_item_pos < data_offset || - extent_item_pos >= data_offset + data_len) - continue; + for (eie = inode_list; eie; eie = eie->next) { pr_debug("ref for %llu resolved, key (%llu EXTEND_DATA %llu), " - "root %llu\n", orig_extent_item_objectid, - key.objectid, key.offset, root); - ret = iterate(key.objectid, - key.offset + (extent_item_pos - data_offset), - root, ctx); + "root %llu\n", extent_item_objectid, + eie->inum, eie->offset, root); + ret = iterate(eie->inum, eie->offset, root, ctx); if (ret) { - pr_debug("stopping iteration because ret=%d\n", ret); + pr_debug("stopping iteration for %llu due to ret=%d\n", + extent_item_objectid, ret); break; } } - free_extent_buffer(eb); - return ret; } @@ -1137,63 +1522,69 @@ static int iterate_leaf_refs(struct btrfs_fs_info *fs_info, * calls iterate() for every inode that references the extent identified by * the given parameters. * when the iterator function returns a non-zero value, iteration stops. - * path is guaranteed to be in released state when iterate() is called. */ int iterate_extent_inodes(struct btrfs_fs_info *fs_info, - struct btrfs_path *path, u64 extent_item_objectid, u64 extent_item_pos, + int search_commit_root, iterate_extent_inodes_t *iterate, void *ctx) { int ret; - struct list_head data_refs = LIST_HEAD_INIT(data_refs); - struct list_head shared_refs = LIST_HEAD_INIT(shared_refs); - struct btrfs_trans_handle *trans; - struct ulist *refs; - struct ulist *roots; + struct btrfs_trans_handle *trans = NULL; + struct ulist *refs = NULL; + struct ulist *roots = NULL; struct ulist_node *ref_node = NULL; struct ulist_node *root_node = NULL; - struct seq_list seq_elem; - struct btrfs_delayed_ref_root *delayed_refs; - - trans = btrfs_join_transaction(fs_info->extent_root); - if (IS_ERR(trans)) - return PTR_ERR(trans); + struct seq_list tree_mod_seq_elem = {}; + struct ulist_iterator ref_uiter; + struct ulist_iterator root_uiter; pr_debug("resolving all inodes for extent %llu\n", extent_item_objectid); - delayed_refs = &trans->transaction->delayed_refs; - spin_lock(&delayed_refs->lock); - btrfs_get_delayed_seq(delayed_refs, &seq_elem); - spin_unlock(&delayed_refs->lock); + if (!search_commit_root) { + trans = btrfs_join_transaction(fs_info->extent_root); + if (IS_ERR(trans)) + return PTR_ERR(trans); + btrfs_get_tree_mod_seq(fs_info, &tree_mod_seq_elem); + } else { + down_read(&fs_info->commit_root_sem); + } ret = btrfs_find_all_leafs(trans, fs_info, extent_item_objectid, - extent_item_pos, seq_elem.seq, - &refs); - + tree_mod_seq_elem.seq, &refs, + &extent_item_pos); if (ret) goto out; - while (!ret && (ref_node = ulist_next(refs, ref_node))) { - ret = btrfs_find_all_roots(trans, fs_info, ref_node->val, -1, - seq_elem.seq, &roots); + ULIST_ITER_INIT(&ref_uiter); + while (!ret && (ref_node = ulist_next(refs, &ref_uiter))) { + ret = __btrfs_find_all_roots(trans, fs_info, ref_node->val, + tree_mod_seq_elem.seq, &roots); if (ret) break; - while (!ret && (root_node = ulist_next(roots, root_node))) { - pr_debug("root %llu references leaf %llu\n", - root_node->val, ref_node->val); - ret = iterate_leaf_refs(fs_info, path, ref_node->val, + ULIST_ITER_INIT(&root_uiter); + while (!ret && (root_node = ulist_next(roots, &root_uiter))) { + pr_debug("root %llu references leaf %llu, data list " + "%#llx\n", root_node->val, ref_node->val, + ref_node->aux); + ret = iterate_leaf_refs((struct extent_inode_elem *) + (uintptr_t)ref_node->aux, + root_node->val, extent_item_objectid, - extent_item_pos, root_node->val, iterate, ctx); } + ulist_free(roots); } - ulist_free(refs); - ulist_free(roots); + free_leaf_list(refs); out: - btrfs_put_delayed_seq(delayed_refs, &seq_elem); - btrfs_end_transaction(trans, fs_info->extent_root); + if (!search_commit_root) { + btrfs_put_tree_mod_seq(fs_info, &tree_mod_seq_elem); + btrfs_end_transaction(trans, fs_info->extent_root); + } else { + up_read(&fs_info->commit_root_sem); + } + return ret; } @@ -1203,28 +1594,33 @@ int iterate_inodes_from_logical(u64 logical, struct btrfs_fs_info *fs_info, { int ret; u64 extent_item_pos; + u64 flags = 0; struct btrfs_key found_key; + int search_commit_root = path->search_commit_root; - ret = extent_from_logical(fs_info, logical, path, - &found_key); + ret = extent_from_logical(fs_info, logical, path, &found_key, &flags); btrfs_release_path(path); - if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK) - ret = -EINVAL; if (ret < 0) return ret; + if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) + return -EINVAL; extent_item_pos = logical - found_key.objectid; - ret = iterate_extent_inodes(fs_info, path, found_key.objectid, - extent_item_pos, iterate, ctx); + ret = iterate_extent_inodes(fs_info, found_key.objectid, + extent_item_pos, search_commit_root, + iterate, ctx); return ret; } -static int iterate_irefs(u64 inum, struct btrfs_root *fs_root, - struct btrfs_path *path, - iterate_irefs_t *iterate, void *ctx) +typedef int (iterate_irefs_t)(u64 parent, u32 name_len, unsigned long name_off, + struct extent_buffer *eb, void *ctx); + +static int iterate_inode_refs(u64 inum, struct btrfs_root *fs_root, + struct btrfs_path *path, + iterate_irefs_t *iterate, void *ctx) { - int ret; + int ret = 0; int slot; u32 cur; u32 len; @@ -1236,9 +1632,9 @@ static int iterate_irefs(u64 inum, struct btrfs_root *fs_root, struct btrfs_inode_ref *iref; struct btrfs_key found_key; - while (1) { + while (!ret) { ret = inode_ref_info(inum, parent ? parent+1 : 0, fs_root, path, - &found_key); + &found_key); if (ret < 0) break; if (ret) { @@ -1249,30 +1645,103 @@ static int iterate_irefs(u64 inum, struct btrfs_root *fs_root, parent = found_key.offset; slot = path->slots[0]; - eb = path->nodes[0]; - /* make sure we can use eb after releasing the path */ - atomic_inc(&eb->refs); + eb = btrfs_clone_extent_buffer(path->nodes[0]); + if (!eb) { + ret = -ENOMEM; + break; + } + extent_buffer_get(eb); + btrfs_tree_read_lock(eb); + btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK); btrfs_release_path(path); - item = btrfs_item_nr(eb, slot); + item = btrfs_item_nr(slot); iref = btrfs_item_ptr(eb, slot, struct btrfs_inode_ref); for (cur = 0; cur < btrfs_item_size(eb, item); cur += len) { name_len = btrfs_inode_ref_name_len(eb, iref); /* path must be released before calling iterate()! */ pr_debug("following ref at offset %u for inode %llu in " - "tree %llu\n", cur, - (unsigned long long)found_key.objectid, - (unsigned long long)fs_root->objectid); - ret = iterate(parent, iref, eb, ctx); - if (ret) { - free_extent_buffer(eb); + "tree %llu\n", cur, found_key.objectid, + fs_root->objectid); + ret = iterate(parent, name_len, + (unsigned long)(iref + 1), eb, ctx); + if (ret) break; - } len = sizeof(*iref) + name_len; iref = (struct btrfs_inode_ref *)((char *)iref + len); } + btrfs_tree_read_unlock_blocking(eb); + free_extent_buffer(eb); + } + + btrfs_release_path(path); + + return ret; +} + +static int iterate_inode_extrefs(u64 inum, struct btrfs_root *fs_root, + struct btrfs_path *path, + iterate_irefs_t *iterate, void *ctx) +{ + int ret; + int slot; + u64 offset = 0; + u64 parent; + int found = 0; + struct extent_buffer *eb; + struct btrfs_inode_extref *extref; + struct extent_buffer *leaf; + u32 item_size; + u32 cur_offset; + unsigned long ptr; + + while (1) { + ret = btrfs_find_one_extref(fs_root, inum, offset, path, &extref, + &offset); + if (ret < 0) + break; + if (ret) { + ret = found ? 0 : -ENOENT; + break; + } + ++found; + + slot = path->slots[0]; + eb = btrfs_clone_extent_buffer(path->nodes[0]); + if (!eb) { + ret = -ENOMEM; + break; + } + extent_buffer_get(eb); + + btrfs_tree_read_lock(eb); + btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK); + btrfs_release_path(path); + + leaf = path->nodes[0]; + item_size = btrfs_item_size_nr(leaf, slot); + ptr = btrfs_item_ptr_offset(leaf, slot); + cur_offset = 0; + + while (cur_offset < item_size) { + u32 name_len; + + extref = (struct btrfs_inode_extref *)(ptr + cur_offset); + parent = btrfs_inode_extref_parent(eb, extref); + name_len = btrfs_inode_extref_name_len(eb, extref); + ret = iterate(parent, name_len, + (unsigned long)&extref->name, eb, ctx); + if (ret) + break; + + cur_offset += btrfs_inode_extref_name_len(leaf, extref); + cur_offset += sizeof(*extref); + } + btrfs_tree_read_unlock_blocking(eb); free_extent_buffer(eb); + + offset++; } btrfs_release_path(path); @@ -1280,12 +1749,32 @@ static int iterate_irefs(u64 inum, struct btrfs_root *fs_root, return ret; } +static int iterate_irefs(u64 inum, struct btrfs_root *fs_root, + struct btrfs_path *path, iterate_irefs_t *iterate, + void *ctx) +{ + int ret; + int found_refs = 0; + + ret = iterate_inode_refs(inum, fs_root, path, iterate, ctx); + if (!ret) + ++found_refs; + else if (ret != -ENOENT) + return ret; + + ret = iterate_inode_extrefs(inum, fs_root, path, iterate, ctx); + if (ret == -ENOENT && found_refs) + return 0; + + return ret; +} + /* * returns 0 if the path could be dumped (probably truncated) * returns <0 in case of an error */ -static int inode_to_path(u64 inum, struct btrfs_inode_ref *iref, - struct extent_buffer *eb, void *ctx) +static int inode_to_path(u64 inum, u32 name_len, unsigned long name_off, + struct extent_buffer *eb, void *ctx) { struct inode_fs_paths *ipath = ctx; char *fspath; @@ -1298,20 +1787,16 @@ static int inode_to_path(u64 inum, struct btrfs_inode_ref *iref, ipath->fspath->bytes_left - s_ptr : 0; fspath_min = (char *)ipath->fspath->val + (i + 1) * s_ptr; - fspath = iref_to_path(ipath->fs_root, ipath->btrfs_path, iref, eb, - inum, fspath_min, bytes_left); + fspath = btrfs_ref_to_path(ipath->fs_root, ipath->btrfs_path, name_len, + name_off, eb, inum, fspath_min, bytes_left); if (IS_ERR(fspath)) return PTR_ERR(fspath); if (fspath > fspath_min) { - pr_debug("path resolved: %s\n", fspath); ipath->fspath->val[i] = (u64)(unsigned long)fspath; ++ipath->fspath->elem_cnt; ipath->fspath->bytes_left = fspath - fspath_min; } else { - pr_debug("missed path, not enough space. missing bytes: %lu, " - "constructed so far: %s\n", - (unsigned long)(fspath_min - fspath), fspath_min); ++ipath->fspath->elem_missed; ipath->fspath->bytes_missing += fspath_min - fspath; ipath->fspath->bytes_left = 0; @@ -1333,22 +1818,16 @@ static int inode_to_path(u64 inum, struct btrfs_inode_ref *iref, int paths_from_inode(u64 inum, struct inode_fs_paths *ipath) { return iterate_irefs(inum, ipath->fs_root, ipath->btrfs_path, - inode_to_path, ipath); + inode_to_path, ipath); } -/* - * allocates space to return multiple file system paths for an inode. - * total_bytes to allocate are passed, note that space usable for actual path - * information will be total_bytes - sizeof(struct inode_fs_paths). - * the returned pointer must be freed with free_ipath() in the end. - */ struct btrfs_data_container *init_data_container(u32 total_bytes) { struct btrfs_data_container *data; size_t alloc_bytes; alloc_bytes = max_t(size_t, total_bytes, sizeof(*data)); - data = kmalloc(alloc_bytes, GFP_NOFS); + data = vmalloc(alloc_bytes); if (!data) return ERR_PTR(-ENOMEM); @@ -1397,5 +1876,8 @@ struct inode_fs_paths *init_ipath(s32 total_bytes, struct btrfs_root *fs_root, void free_ipath(struct inode_fs_paths *ipath) { + if (!ipath) + return; + vfree(ipath->fspath); kfree(ipath); } |