/* * Copyright (C) 2007 Oracle. All rights reserved. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public * License v2 as published by the Free Software Foundation. * * 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., 59 Temple Place - Suite 330, * Boston, MA 021110-1307, USA. */ #include #include #include #include "kerncompat.h" #include "radix-tree.h" #include "ctree.h" #include "disk-io.h" #include "print-tree.h" #include "transaction.h" #include "crc32c.h" #include "volumes.h" #include "free-space-cache.h" #include "math.h" #include "utils.h" #define PENDING_EXTENT_INSERT 0 #define PENDING_EXTENT_DELETE 1 #define PENDING_BACKREF_UPDATE 2 struct pending_extent_op { int type; u64 bytenr; u64 num_bytes; u64 flags; struct btrfs_disk_key key; int level; }; static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 root_objectid, u64 generation, u64 flags, struct btrfs_disk_key *key, int level, struct btrfs_key *ins); static int __free_extent(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 bytenr, u64 num_bytes, u64 parent, u64 root_objectid, u64 owner_objectid, u64 owner_offset, int refs_to_drop); static int finish_current_insert(struct btrfs_trans_handle *trans, struct btrfs_root *extent_root); static int del_pending_extents(struct btrfs_trans_handle *trans, struct btrfs_root *extent_root); static struct btrfs_block_group_cache * btrfs_find_block_group(struct btrfs_root *root, struct btrfs_block_group_cache *hint, u64 search_start, int data, int owner); static int remove_sb_from_cache(struct btrfs_root *root, struct btrfs_block_group_cache *cache) { u64 bytenr; u64 *logical; int stripe_len; int i, nr, ret; struct extent_io_tree *free_space_cache; free_space_cache = &root->fs_info->free_space_cache; for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) { bytenr = btrfs_sb_offset(i); ret = btrfs_rmap_block(&root->fs_info->mapping_tree, cache->key.objectid, bytenr, 0, &logical, &nr, &stripe_len); BUG_ON(ret); while (nr--) { clear_extent_dirty(free_space_cache, logical[nr], logical[nr] + stripe_len - 1, GFP_NOFS); } kfree(logical); } return 0; } static int cache_block_group(struct btrfs_root *root, struct btrfs_block_group_cache *block_group) { struct btrfs_path *path; int ret; struct btrfs_key key; struct extent_buffer *leaf; struct extent_io_tree *free_space_cache; int slot; u64 last; u64 hole_size; if (!block_group) return 0; root = root->fs_info->extent_root; free_space_cache = &root->fs_info->free_space_cache; if (block_group->cached) return 0; path = btrfs_alloc_path(); if (!path) return -ENOMEM; path->reada = 2; last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET); key.objectid = last; key.offset = 0; key.type = 0; ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); if (ret < 0) goto err; while(1) { leaf = path->nodes[0]; slot = path->slots[0]; if (slot >= btrfs_header_nritems(leaf)) { ret = btrfs_next_leaf(root, path); if (ret < 0) goto err; if (ret == 0) { continue; } else { break; } } btrfs_item_key_to_cpu(leaf, &key, slot); if (key.objectid < block_group->key.objectid) { goto next; } if (key.objectid >= block_group->key.objectid + block_group->key.offset) { break; } if (key.type == BTRFS_EXTENT_ITEM_KEY || key.type == BTRFS_METADATA_ITEM_KEY) { if (key.objectid > last) { hole_size = key.objectid - last; set_extent_dirty(free_space_cache, last, last + hole_size - 1, GFP_NOFS); } if (key.type == BTRFS_METADATA_ITEM_KEY) last = key.objectid + root->leafsize; else last = key.objectid + key.offset; } next: path->slots[0]++; } if (block_group->key.objectid + block_group->key.offset > last) { hole_size = block_group->key.objectid + block_group->key.offset - last; set_extent_dirty(free_space_cache, last, last + hole_size - 1, GFP_NOFS); } remove_sb_from_cache(root, block_group); block_group->cached = 1; err: btrfs_free_path(path); return 0; } struct btrfs_block_group_cache *btrfs_lookup_first_block_group(struct btrfs_fs_info *info, u64 bytenr) { struct extent_io_tree *block_group_cache; struct btrfs_block_group_cache *block_group = NULL; u64 ptr; u64 start; u64 end; int ret; bytenr = max_t(u64, bytenr, BTRFS_SUPER_INFO_OFFSET + BTRFS_SUPER_INFO_SIZE); block_group_cache = &info->block_group_cache; ret = find_first_extent_bit(block_group_cache, bytenr, &start, &end, BLOCK_GROUP_DATA | BLOCK_GROUP_METADATA | BLOCK_GROUP_SYSTEM); if (ret) { return NULL; } ret = get_state_private(block_group_cache, start, &ptr); if (ret) return NULL; block_group = (struct btrfs_block_group_cache *)(unsigned long)ptr; return block_group; } struct btrfs_block_group_cache *btrfs_lookup_block_group(struct btrfs_fs_info *info, u64 bytenr) { struct extent_io_tree *block_group_cache; struct btrfs_block_group_cache *block_group = NULL; u64 ptr; u64 start; u64 end; int ret; block_group_cache = &info->block_group_cache; ret = find_first_extent_bit(block_group_cache, bytenr, &start, &end, BLOCK_GROUP_DATA | BLOCK_GROUP_METADATA | BLOCK_GROUP_SYSTEM); if (ret) { return NULL; } ret = get_state_private(block_group_cache, start, &ptr); if (ret) return NULL; block_group = (struct btrfs_block_group_cache *)(unsigned long)ptr; if (block_group->key.objectid <= bytenr && bytenr < block_group->key.objectid + block_group->key.offset) return block_group; return NULL; } static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits) { return (cache->flags & bits) == bits; } static int noinline find_search_start(struct btrfs_root *root, struct btrfs_block_group_cache **cache_ret, u64 *start_ret, int num, int data) { int ret; struct btrfs_block_group_cache *cache = *cache_ret; u64 last = *start_ret; u64 start = 0; u64 end = 0; u64 search_start = *start_ret; int wrapped = 0; if (!cache) goto out; again: ret = cache_block_group(root, cache); if (ret) goto out; last = max(search_start, cache->key.objectid); if (cache->ro || !block_group_bits(cache, data)) goto new_group; while(1) { ret = find_first_extent_bit(&root->fs_info->free_space_cache, last, &start, &end, EXTENT_DIRTY); if (ret) { goto new_group; } start = max(last, start); last = end + 1; if (last - start < num) { continue; } if (start + num > cache->key.objectid + cache->key.offset) { goto new_group; } *start_ret = start; return 0; } out: *start_ret = last; cache = btrfs_lookup_block_group(root->fs_info, search_start); if (!cache) { printk("Unable to find block group for %llu\n", (unsigned long long)search_start); WARN_ON(1); } return -ENOSPC; new_group: last = cache->key.objectid + cache->key.offset; wrapped: cache = btrfs_lookup_first_block_group(root->fs_info, last); if (!cache) { if (!wrapped) { wrapped = 1; last = search_start; goto wrapped; } goto out; } *cache_ret = cache; goto again; } static int block_group_state_bits(u64 flags) { int bits = 0; if (flags & BTRFS_BLOCK_GROUP_DATA) bits |= BLOCK_GROUP_DATA; if (flags & BTRFS_BLOCK_GROUP_METADATA) bits |= BLOCK_GROUP_METADATA; if (flags & BTRFS_BLOCK_GROUP_SYSTEM) bits |= BLOCK_GROUP_SYSTEM; return bits; } static struct btrfs_block_group_cache * btrfs_find_block_group(struct btrfs_root *root, struct btrfs_block_group_cache *hint, u64 search_start, int data, int owner) { struct btrfs_block_group_cache *cache; struct extent_io_tree *block_group_cache; struct btrfs_block_group_cache *found_group = NULL; struct btrfs_fs_info *info = root->fs_info; u64 used; u64 last = 0; u64 hint_last; u64 start; u64 end; u64 free_check; u64 ptr; int bit; int ret; int full_search = 0; int factor = 10; block_group_cache = &info->block_group_cache; if (!owner) factor = 10; bit = block_group_state_bits(data); if (search_start) { struct btrfs_block_group_cache *shint; shint = btrfs_lookup_block_group(info, search_start); if (shint && !shint->ro && block_group_bits(shint, data)) { used = btrfs_block_group_used(&shint->item); if (used + shint->pinned < div_factor(shint->key.offset, factor)) { return shint; } } } if (hint && !hint->ro && block_group_bits(hint, data)) { used = btrfs_block_group_used(&hint->item); if (used + hint->pinned < div_factor(hint->key.offset, factor)) { return hint; } last = hint->key.objectid + hint->key.offset; hint_last = last; } else { if (hint) hint_last = max(hint->key.objectid, search_start); else hint_last = search_start; last = hint_last; } again: while(1) { ret = find_first_extent_bit(block_group_cache, last, &start, &end, bit); if (ret) break; ret = get_state_private(block_group_cache, start, &ptr); if (ret) break; cache = (struct btrfs_block_group_cache *)(unsigned long)ptr; last = cache->key.objectid + cache->key.offset; used = btrfs_block_group_used(&cache->item); if (!cache->ro && block_group_bits(cache, data)) { if (full_search) free_check = cache->key.offset; else free_check = div_factor(cache->key.offset, factor); if (used + cache->pinned < free_check) { found_group = cache; goto found; } } cond_resched(); } if (!full_search) { last = search_start; full_search = 1; goto again; } found: return found_group; } /* * Back reference rules. Back refs have three main goals: * * 1) differentiate between all holders of references to an extent so that * when a reference is dropped we can make sure it was a valid reference * before freeing the extent. * * 2) Provide enough information to quickly find the holders of an extent * if we notice a given block is corrupted or bad. * * 3) Make it easy to migrate blocks for FS shrinking or storage pool * maintenance. This is actually the same as #2, but with a slightly * different use case. * * There are two kinds of back refs. The implicit back refs is optimized * for pointers in non-shared tree blocks. For a given pointer in a block, * back refs of this kind provide information about the block's owner tree * and the pointer's key. These information allow us to find the block by * b-tree searching. The full back refs is for pointers in tree blocks not * referenced by their owner trees. The location of tree block is recorded * in the back refs. Actually the full back refs is generic, and can be * used in all cases the implicit back refs is used. The major shortcoming * of the full back refs is its overhead. Every time a tree block gets * COWed, we have to update back refs entry for all pointers in it. * * For a newly allocated tree block, we use implicit back refs for * pointers in it. This means most tree related operations only involve * implicit back refs. For a tree block created in old transaction, the * only way to drop a reference to it is COW it. So we can detect the * event that tree block loses its owner tree's reference and do the * back refs conversion. * * When a tree block is COW'd through a tree, there are four cases: * * The reference count of the block is one and the tree is the block's * owner tree. Nothing to do in this case. * * The reference count of the block is one and the tree is not the * block's owner tree. In this case, full back refs is used for pointers * in the block. Remove these full back refs, add implicit back refs for * every pointers in the new block. * * The reference count of the block is greater than one and the tree is * the block's owner tree. In this case, implicit back refs is used for * pointers in the block. Add full back refs for every pointers in the * block, increase lower level extents' reference counts. The original * implicit back refs are entailed to the new block. * * The reference count of the block is greater than one and the tree is * not the block's owner tree. Add implicit back refs for every pointer in * the new block, increase lower level extents' reference count. * * Back Reference Key composing: * * The key objectid corresponds to the first byte in the extent, * The key type is used to differentiate between types of back refs. * There are different meanings of the key offset for different types * of back refs. * * File extents can be referenced by: * * - multiple snapshots, subvolumes, or different generations in one subvol * - different files inside a single subvolume * - different offsets inside a file (bookend extents in file.c) * * The extent ref structure for the implicit back refs has fields for: * * - Objectid of the subvolume root * - objectid of the file holding the reference * - original offset in the file * - how many bookend extents * * The key offset for the implicit back refs is hash of the first * three fields. * * The extent ref structure for the full back refs has field for: * * - number of pointers in the tree leaf * * The key offset for the implicit back refs is the first byte of * the tree leaf * * When a file extent is allocated, The implicit back refs is used. * the fields are filled in: * * (root_key.objectid, inode objectid, offset in file, 1) * * When a file extent is removed file truncation, we find the * corresponding implicit back refs and check the following fields: * * (btrfs_header_owner(leaf), inode objectid, offset in file) * * Btree extents can be referenced by: * * - Different subvolumes * * Both the implicit back refs and the full back refs for tree blocks * only consist of key. The key offset for the implicit back refs is * objectid of block's owner tree. The key offset for the full back refs * is the first byte of parent block. * * When implicit back refs is used, information about the lowest key and * level of the tree block are required. These information are stored in * tree block info structure. */ #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 static int convert_extent_item_v0(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, u64 owner, u32 extra_size) { struct btrfs_extent_item *item; struct btrfs_extent_item_v0 *ei0; struct btrfs_extent_ref_v0 *ref0; struct btrfs_tree_block_info *bi; struct extent_buffer *leaf; struct btrfs_key key; struct btrfs_key found_key; u32 new_size = sizeof(*item); u64 refs; int ret; leaf = path->nodes[0]; BUG_ON(btrfs_item_size_nr(leaf, path->slots[0]) != sizeof(*ei0)); btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); ei0 = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item_v0); refs = btrfs_extent_refs_v0(leaf, ei0); if (owner == (u64)-1) { while (1) { if (path->slots[0] >= btrfs_header_nritems(leaf)) { ret = btrfs_next_leaf(root, path); if (ret < 0) return ret; BUG_ON(ret > 0); leaf = path->nodes[0]; } btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); BUG_ON(key.objectid != found_key.objectid); if (found_key.type != BTRFS_EXTENT_REF_V0_KEY) { path->slots[0]++; continue; } ref0 = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_ref_v0); owner = btrfs_ref_objectid_v0(leaf, ref0); break; } } btrfs_release_path(path); if (owner < BTRFS_FIRST_FREE_OBJECTID) new_size += sizeof(*bi); new_size -= sizeof(*ei0); ret = btrfs_search_slot(trans, root, &key, path, new_size, 1); if (ret < 0) return ret; BUG_ON(ret); ret = btrfs_extend_item(trans, root, path, new_size); BUG_ON(ret); leaf = path->nodes[0]; item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item); btrfs_set_extent_refs(leaf, item, refs); /* FIXME: get real generation */ btrfs_set_extent_generation(leaf, item, 0); if (owner < BTRFS_FIRST_FREE_OBJECTID) { btrfs_set_extent_flags(leaf, item, BTRFS_EXTENT_FLAG_TREE_BLOCK | BTRFS_BLOCK_FLAG_FULL_BACKREF); bi = (struct btrfs_tree_block_info *)(item + 1); /* FIXME: get first key of the block */ memset_extent_buffer(leaf, 0, (unsigned long)bi, sizeof(*bi)); btrfs_set_tree_block_level(leaf, bi, (int)owner); } else { btrfs_set_extent_flags(leaf, item, BTRFS_EXTENT_FLAG_DATA); } btrfs_mark_buffer_dirty(leaf); return 0; } #endif static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset) { u32 high_crc = ~(u32)0; u32 low_crc = ~(u32)0; __le64 lenum; lenum = cpu_to_le64(root_objectid); high_crc = btrfs_crc32c(high_crc, &lenum, sizeof(lenum)); lenum = cpu_to_le64(owner); low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum)); lenum = cpu_to_le64(offset); low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum)); return ((u64)high_crc << 31) ^ (u64)low_crc; } static u64 hash_extent_data_ref_item(struct extent_buffer *leaf, struct btrfs_extent_data_ref *ref) { return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf, ref), btrfs_extent_data_ref_objectid(leaf, ref), btrfs_extent_data_ref_offset(leaf, ref)); } static int match_extent_data_ref(struct extent_buffer *leaf, struct btrfs_extent_data_ref *ref, u64 root_objectid, u64 owner, u64 offset) { if (btrfs_extent_data_ref_root(leaf, ref) != root_objectid || btrfs_extent_data_ref_objectid(leaf, ref) != owner || btrfs_extent_data_ref_offset(leaf, ref) != offset) return 0; return 1; } static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, u64 bytenr, u64 parent, u64 root_objectid, u64 owner, u64 offset) { struct btrfs_key key; struct btrfs_extent_data_ref *ref; struct extent_buffer *leaf; u32 nritems; int ret; int recow; int err = -ENOENT; key.objectid = bytenr; if (parent) { key.type = BTRFS_SHARED_DATA_REF_KEY; key.offset = parent; } else { key.type = BTRFS_EXTENT_DATA_REF_KEY; key.offset = hash_extent_data_ref(root_objectid, owner, offset); } again: recow = 0; ret = btrfs_search_slot(trans, root, &key, path, -1, 1); if (ret < 0) { err = ret; goto fail; } if (parent) { if (!ret) return 0; #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 key.type = BTRFS_EXTENT_REF_V0_KEY; btrfs_release_path(path); ret = btrfs_search_slot(trans, root, &key, path, -1, 1); if (ret < 0) { err = ret; goto fail; } if (!ret) return 0; #endif goto fail; } leaf = path->nodes[0]; nritems = btrfs_header_nritems(leaf); while (1) { if (path->slots[0] >= nritems) { ret = btrfs_next_leaf(root, path); if (ret < 0) err = ret; if (ret) goto fail; leaf = path->nodes[0]; nritems = btrfs_header_nritems(leaf); recow = 1; } btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); if (key.objectid != bytenr || key.type != BTRFS_EXTENT_DATA_REF_KEY) goto fail; ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_data_ref); if (match_extent_data_ref(leaf, ref, root_objectid, owner, offset)) { if (recow) { btrfs_release_path(path); goto again; } err = 0; break; } path->slots[0]++; } fail: return err; } static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, u64 bytenr, u64 parent, u64 root_objectid, u64 owner, u64 offset, int refs_to_add) { struct btrfs_key key; struct extent_buffer *leaf; u32 size; u32 num_refs; int ret; key.objectid = bytenr; if (parent) { key.type = BTRFS_SHARED_DATA_REF_KEY; key.offset = parent; size = sizeof(struct btrfs_shared_data_ref); } else { key.type = BTRFS_EXTENT_DATA_REF_KEY; key.offset = hash_extent_data_ref(root_objectid, owner, offset); size = sizeof(struct btrfs_extent_data_ref); } ret = btrfs_insert_empty_item(trans, root, path, &key, size); if (ret && ret != -EEXIST) goto fail; leaf = path->nodes[0]; if (parent) { struct btrfs_shared_data_ref *ref; ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_shared_data_ref); if (ret == 0) { btrfs_set_shared_data_ref_count(leaf, ref, refs_to_add); } else { num_refs = btrfs_shared_data_ref_count(leaf, ref); num_refs += refs_to_add; btrfs_set_shared_data_ref_count(leaf, ref, num_refs); } } else { struct btrfs_extent_data_ref *ref; while (ret == -EEXIST) { ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_data_ref); if (match_extent_data_ref(leaf, ref, root_objectid, owner, offset)) break; btrfs_release_path(path); key.offset++; ret = btrfs_insert_empty_item(trans, root, path, &key, size); if (ret && ret != -EEXIST) goto fail; leaf = path->nodes[0]; } ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_data_ref); if (ret == 0) { btrfs_set_extent_data_ref_root(leaf, ref, root_objectid); btrfs_set_extent_data_ref_objectid(leaf, ref, owner); btrfs_set_extent_data_ref_offset(leaf, ref, offset); btrfs_set_extent_data_ref_count(leaf, ref, refs_to_add); } else { num_refs = btrfs_extent_data_ref_count(leaf, ref); num_refs += refs_to_add; btrfs_set_extent_data_ref_count(leaf, ref, num_refs); } } btrfs_mark_buffer_dirty(leaf); ret = 0; fail: btrfs_release_path(path); return ret; } static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, int refs_to_drop) { struct btrfs_key key; struct btrfs_extent_data_ref *ref1 = NULL; struct btrfs_shared_data_ref *ref2 = NULL; struct extent_buffer *leaf; u32 num_refs = 0; int ret = 0; leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); if (key.type == BTRFS_EXTENT_DATA_REF_KEY) { ref1 = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_data_ref); num_refs = btrfs_extent_data_ref_count(leaf, ref1); } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) { ref2 = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_shared_data_ref); num_refs = btrfs_shared_data_ref_count(leaf, ref2); #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) { struct btrfs_extent_ref_v0 *ref0; ref0 = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_ref_v0); num_refs = btrfs_ref_count_v0(leaf, ref0); #endif } else { BUG(); } BUG_ON(num_refs < refs_to_drop); num_refs -= refs_to_drop; if (num_refs == 0) { ret = btrfs_del_item(trans, root, path); } else { if (key.type == BTRFS_EXTENT_DATA_REF_KEY) btrfs_set_extent_data_ref_count(leaf, ref1, num_refs); else if (key.type == BTRFS_SHARED_DATA_REF_KEY) btrfs_set_shared_data_ref_count(leaf, ref2, num_refs); #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 else { struct btrfs_extent_ref_v0 *ref0; ref0 = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_ref_v0); btrfs_set_ref_count_v0(leaf, ref0, num_refs); } #endif btrfs_mark_buffer_dirty(leaf); } return ret; } static noinline u32 extent_data_ref_count(struct btrfs_root *root, struct btrfs_path *path, struct btrfs_extent_inline_ref *iref) { struct btrfs_key key; struct extent_buffer *leaf; struct btrfs_extent_data_ref *ref1; struct btrfs_shared_data_ref *ref2; u32 num_refs = 0; leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); if (iref) { if (btrfs_extent_inline_ref_type(leaf, iref) == BTRFS_EXTENT_DATA_REF_KEY) { ref1 = (struct btrfs_extent_data_ref *)(&iref->offset); num_refs = btrfs_extent_data_ref_count(leaf, ref1); } else { ref2 = (struct btrfs_shared_data_ref *)(iref + 1); num_refs = btrfs_shared_data_ref_count(leaf, ref2); } } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) { ref1 = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_data_ref); num_refs = btrfs_extent_data_ref_count(leaf, ref1); } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) { ref2 = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_shared_data_ref); num_refs = btrfs_shared_data_ref_count(leaf, ref2); #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) { struct btrfs_extent_ref_v0 *ref0; ref0 = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_ref_v0); num_refs = btrfs_ref_count_v0(leaf, ref0); #endif } else { BUG(); } return num_refs; } static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, u64 bytenr, u64 parent, u64 root_objectid) { struct btrfs_key key; int ret; key.objectid = bytenr; if (parent) { key.type = BTRFS_SHARED_BLOCK_REF_KEY; key.offset = parent; } else { key.type = BTRFS_TREE_BLOCK_REF_KEY; key.offset = root_objectid; } ret = btrfs_search_slot(trans, root, &key, path, -1, 1); if (ret > 0) ret = -ENOENT; #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 if (ret == -ENOENT && parent) { btrfs_release_path(path); key.type = BTRFS_EXTENT_REF_V0_KEY; ret = btrfs_search_slot(trans, root, &key, path, -1, 1); if (ret > 0) ret = -ENOENT; } #endif return ret; } static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, u64 bytenr, u64 parent, u64 root_objectid) { struct btrfs_key key; int ret; key.objectid = bytenr; if (parent) { key.type = BTRFS_SHARED_BLOCK_REF_KEY; key.offset = parent; } else { key.type = BTRFS_TREE_BLOCK_REF_KEY; key.offset = root_objectid; } ret = btrfs_insert_empty_item(trans, root, path, &key, 0); btrfs_release_path(path); return ret; } static inline int extent_ref_type(u64 parent, u64 owner) { int type; if (owner < BTRFS_FIRST_FREE_OBJECTID) { if (parent > 0) type = BTRFS_SHARED_BLOCK_REF_KEY; else type = BTRFS_TREE_BLOCK_REF_KEY; } else { if (parent > 0) type = BTRFS_SHARED_DATA_REF_KEY; else type = BTRFS_EXTENT_DATA_REF_KEY; } return type; } static int lookup_inline_extent_backref(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, struct btrfs_extent_inline_ref **ref_ret, u64 bytenr, u64 num_bytes, u64 parent, u64 root_objectid, u64 owner, u64 offset, int insert) { struct btrfs_key key; struct extent_buffer *leaf; struct btrfs_extent_item *ei; struct btrfs_extent_inline_ref *iref; u64 flags; u32 item_size; unsigned long ptr; unsigned long end; int extra_size; int type; int want; int ret; int err = 0; int skinny_metadata = btrfs_fs_incompat(root->fs_info, BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA); key.objectid = bytenr; key.type = BTRFS_EXTENT_ITEM_KEY; key.offset = num_bytes; want = extent_ref_type(parent, owner); if (insert) extra_size = btrfs_extent_inline_ref_size(want); else extra_size = -1; if (owner < BTRFS_FIRST_FREE_OBJECTID && skinny_metadata) { skinny_metadata = 1; key.type = BTRFS_METADATA_ITEM_KEY; key.offset = owner; } else if (skinny_metadata) { skinny_metadata = 0; } again: ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1); if (ret < 0) { err = ret; goto out; } /* * We may be a newly converted file system which still has the old fat * extent entries for metadata, so try and see if we have one of those. */ if (ret > 0 && skinny_metadata) { skinny_metadata = 0; if (path->slots[0]) { path->slots[0]--; btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); if (key.objectid == bytenr && key.type == BTRFS_EXTENT_ITEM_KEY && key.offset == num_bytes) ret = 0; } if (ret) { key.type = BTRFS_EXTENT_ITEM_KEY; key.offset = num_bytes; btrfs_release_path(path); goto again; } } if (ret) { printf("Failed to find [%llu, %u, %llu]\n", key.objectid, key.type, key.offset); return -ENOENT; } BUG_ON(ret); leaf = path->nodes[0]; item_size = btrfs_item_size_nr(leaf, path->slots[0]); #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 if (item_size < sizeof(*ei)) { if (!insert) { err = -ENOENT; goto out; } ret = convert_extent_item_v0(trans, root, path, owner, extra_size); if (ret < 0) { err = ret; goto out; } leaf = path->nodes[0]; item_size = btrfs_item_size_nr(leaf, path->slots[0]); } #endif if (item_size < sizeof(*ei)) { printf("Size is %u, needs to be %u, slot %d\n", (unsigned)item_size, (unsigned)sizeof(*ei), path->slots[0]); btrfs_print_leaf(root, leaf); return -EINVAL; } BUG_ON(item_size < sizeof(*ei)); ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item); flags = btrfs_extent_flags(leaf, ei); ptr = (unsigned long)(ei + 1); end = (unsigned long)ei + item_size; if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK && !skinny_metadata) { ptr += sizeof(struct btrfs_tree_block_info); BUG_ON(ptr > end); } else if (!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) { if (!(flags & BTRFS_EXTENT_FLAG_DATA)) { return -EIO; } } err = -ENOENT; while (1) { if (ptr >= end) { WARN_ON(ptr > end); break; } iref = (struct btrfs_extent_inline_ref *)ptr; type = btrfs_extent_inline_ref_type(leaf, iref); if (want < type) break; if (want > type) { ptr += btrfs_extent_inline_ref_size(type); continue; } if (type == BTRFS_EXTENT_DATA_REF_KEY) { struct btrfs_extent_data_ref *dref; dref = (struct btrfs_extent_data_ref *)(&iref->offset); if (match_extent_data_ref(leaf, dref, root_objectid, owner, offset)) { err = 0; break; } if (hash_extent_data_ref_item(leaf, dref) < hash_extent_data_ref(root_objectid, owner, offset)) break; } else { u64 ref_offset; ref_offset = btrfs_extent_inline_ref_offset(leaf, iref); if (parent > 0) { if (parent == ref_offset) { err = 0; break; } if (ref_offset < parent) break; } else { if (root_objectid == ref_offset) { err = 0; break; } if (ref_offset < root_objectid) break; } } ptr += btrfs_extent_inline_ref_size(type); } if (err == -ENOENT && insert) { if (item_size + extra_size >= BTRFS_MAX_EXTENT_ITEM_SIZE(root)) { err = -EAGAIN; goto out; } /* * To add new inline back ref, we have to make sure * there is no corresponding back ref item. * For simplicity, we just do not add new inline back * ref if there is any back ref item. */ if (find_next_key(path, &key) == 0 && key.objectid == bytenr && key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) { err = -EAGAIN; goto out; } } *ref_ret = (struct btrfs_extent_inline_ref *)ptr; out: return err; } static int setup_inline_extent_backref(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, struct btrfs_extent_inline_ref *iref, u64 parent, u64 root_objectid, u64 owner, u64 offset, int refs_to_add) { struct extent_buffer *leaf; struct btrfs_extent_item *ei; unsigned long ptr; unsigned long end; unsigned long item_offset; u64 refs; int size; int type; int ret; leaf = path->nodes[0]; ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item); item_offset = (unsigned long)iref - (unsigned long)ei; type = extent_ref_type(parent, owner); size = btrfs_extent_inline_ref_size(type); ret = btrfs_extend_item(trans, root, path, size); BUG_ON(ret); ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item); refs = btrfs_extent_refs(leaf, ei); refs += refs_to_add; btrfs_set_extent_refs(leaf, ei, refs); ptr = (unsigned long)ei + item_offset; end = (unsigned long)ei + btrfs_item_size_nr(leaf, path->slots[0]); if (ptr < end - size) memmove_extent_buffer(leaf, ptr + size, ptr, end - size - ptr); iref = (struct btrfs_extent_inline_ref *)ptr; btrfs_set_extent_inline_ref_type(leaf, iref, type); if (type == BTRFS_EXTENT_DATA_REF_KEY) { struct btrfs_extent_data_ref *dref; dref = (struct btrfs_extent_data_ref *)(&iref->offset); btrfs_set_extent_data_ref_root(leaf, dref, root_objectid); btrfs_set_extent_data_ref_objectid(leaf, dref, owner); btrfs_set_extent_data_ref_offset(leaf, dref, offset); btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add); } else if (type == BTRFS_SHARED_DATA_REF_KEY) { struct btrfs_shared_data_ref *sref; sref = (struct btrfs_shared_data_ref *)(iref + 1); btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add); btrfs_set_extent_inline_ref_offset(leaf, iref, parent); } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) { btrfs_set_extent_inline_ref_offset(leaf, iref, parent); } else { btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid); } btrfs_mark_buffer_dirty(leaf); return 0; } static int lookup_extent_backref(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, struct btrfs_extent_inline_ref **ref_ret, u64 bytenr, u64 num_bytes, u64 parent, u64 root_objectid, u64 owner, u64 offset) { int ret; ret = lookup_inline_extent_backref(trans, root, path, ref_ret, bytenr, num_bytes, parent, root_objectid, owner, offset, 0); if (ret != -ENOENT) return ret; btrfs_release_path(path); *ref_ret = NULL; if (owner < BTRFS_FIRST_FREE_OBJECTID) { ret = lookup_tree_block_ref(trans, root, path, bytenr, parent, root_objectid); } else { ret = lookup_extent_data_ref(trans, root, path, bytenr, parent, root_objectid, owner, offset); } return ret; } static int update_inline_extent_backref(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, struct btrfs_extent_inline_ref *iref, int refs_to_mod) { struct extent_buffer *leaf; struct btrfs_extent_item *ei; struct btrfs_extent_data_ref *dref = NULL; struct btrfs_shared_data_ref *sref = NULL; unsigned long ptr; unsigned long end; u32 item_size; int size; int type; int ret; u64 refs; leaf = path->nodes[0]; ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item); refs = btrfs_extent_refs(leaf, ei); WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0); refs += refs_to_mod; btrfs_set_extent_refs(leaf, ei, refs); type = btrfs_extent_inline_ref_type(leaf, iref); if (type == BTRFS_EXTENT_DATA_REF_KEY) { dref = (struct btrfs_extent_data_ref *)(&iref->offset); refs = btrfs_extent_data_ref_count(leaf, dref); } else if (type == BTRFS_SHARED_DATA_REF_KEY) { sref = (struct btrfs_shared_data_ref *)(iref + 1); refs = btrfs_shared_data_ref_count(leaf, sref); } else { refs = 1; BUG_ON(refs_to_mod != -1); } BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod); refs += refs_to_mod; if (refs > 0) { if (type == BTRFS_EXTENT_DATA_REF_KEY) btrfs_set_extent_data_ref_count(leaf, dref, refs); else btrfs_set_shared_data_ref_count(leaf, sref, refs); } else { size = btrfs_extent_inline_ref_size(type); item_size = btrfs_item_size_nr(leaf, path->slots[0]); ptr = (unsigned long)iref; end = (unsigned long)ei + item_size; if (ptr + size < end) memmove_extent_buffer(leaf, ptr, ptr + size, end - ptr - size); item_size -= size; ret = btrfs_truncate_item(trans, root, path, item_size, 1); BUG_ON(ret); } btrfs_mark_buffer_dirty(leaf); return 0; } static int insert_inline_extent_backref(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, u64 bytenr, u64 num_bytes, u64 parent, u64 root_objectid, u64 owner, u64 offset, int refs_to_add) { struct btrfs_extent_inline_ref *iref; int ret; ret = lookup_inline_extent_backref(trans, root, path, &iref, bytenr, num_bytes, parent, root_objectid, owner, offset, 1); if (ret == 0) { BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID); ret = update_inline_extent_backref(trans, root, path, iref, refs_to_add); } else if (ret == -ENOENT) { ret = setup_inline_extent_backref(trans, root, path, iref, parent, root_objectid, owner, offset, refs_to_add); } return ret; } static int insert_extent_backref(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, u64 bytenr, u64 parent, u64 root_objectid, u64 owner, u64 offset, int refs_to_add) { int ret; if (owner >= BTRFS_FIRST_FREE_OBJECTID) { ret = insert_extent_data_ref(trans, root, path, bytenr, parent, root_objectid, owner, offset, refs_to_add); } else { BUG_ON(refs_to_add != 1); ret = insert_tree_block_ref(trans, root, path, bytenr, parent, root_objectid); } return ret; } static int remove_extent_backref(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, struct btrfs_extent_inline_ref *iref, int refs_to_drop, int is_data) { int ret; BUG_ON(!is_data && refs_to_drop != 1); if (iref) { ret = update_inline_extent_backref(trans, root, path, iref, -refs_to_drop); } else if (is_data) { ret = remove_extent_data_ref(trans, root, path, refs_to_drop); } else { ret = btrfs_del_item(trans, root, path); } return ret; } int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 bytenr, u64 num_bytes, u64 parent, u64 root_objectid, u64 owner, u64 offset) { struct btrfs_path *path; struct extent_buffer *leaf; struct btrfs_extent_item *item; u64 refs; int ret; int err = 0; path = btrfs_alloc_path(); if (!path) return -ENOMEM; path->reada = 1; ret = insert_inline_extent_backref(trans, root->fs_info->extent_root, path, bytenr, num_bytes, parent, root_objectid, owner, offset, 1); if (ret == 0) goto out; if (ret != -EAGAIN) { err = ret; goto out; } leaf = path->nodes[0]; item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item); refs = btrfs_extent_refs(leaf, item); btrfs_set_extent_refs(leaf, item, refs + 1); btrfs_mark_buffer_dirty(leaf); btrfs_release_path(path); path->reada = 1; /* now insert the actual backref */ ret = insert_extent_backref(trans, root->fs_info->extent_root, path, bytenr, parent, root_objectid, owner, offset, 1); if (ret) err = ret; out: btrfs_free_path(path); finish_current_insert(trans, root->fs_info->extent_root); del_pending_extents(trans, root->fs_info->extent_root); BUG_ON(err); return err; } int btrfs_extent_post_op(struct btrfs_trans_handle *trans, struct btrfs_root *root) { finish_current_insert(trans, root->fs_info->extent_root); del_pending_extents(trans, root->fs_info->extent_root); return 0; } int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 bytenr, u64 offset, int metadata, u64 *refs, u64 *flags) { struct btrfs_path *path; int ret; struct btrfs_key key; struct extent_buffer *l; struct btrfs_extent_item *item; u32 item_size; u64 num_refs; u64 extent_flags; if (metadata && !btrfs_fs_incompat(root->fs_info, BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA)) { offset = root->leafsize; metadata = 0; } path = btrfs_alloc_path(); if (!path) return -ENOMEM; path->reada = 1; key.objectid = bytenr; key.offset = offset; if (metadata) key.type = BTRFS_METADATA_ITEM_KEY; else key.type = BTRFS_EXTENT_ITEM_KEY; again: ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path, 0, 0); if (ret < 0) goto out; /* * Deal with the fact that we may have mixed SKINNY and normal refs. If * we didn't find what we wanted check and see if we have a normal ref * right next to us, or re-search if we are on the edge of the leaf just * to make sure. */ if (ret > 0 && metadata) { if (path->slots[0]) { path->slots[0]--; btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); if (key.objectid == bytenr && key.type == BTRFS_EXTENT_ITEM_KEY && key.offset == root->leafsize) ret = 0; } if (ret) { btrfs_release_path(path); key.type = BTRFS_EXTENT_ITEM_KEY; key.offset = root->leafsize; metadata = 0; goto again; } } if (ret != 0) { ret = -EIO; goto out; } l = path->nodes[0]; item_size = btrfs_item_size_nr(l, path->slots[0]); if (item_size >= sizeof(*item)) { item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item); num_refs = btrfs_extent_refs(l, item); extent_flags = btrfs_extent_flags(l, item); } else { #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 struct btrfs_extent_item_v0 *ei0; BUG_ON(item_size != sizeof(*ei0)); ei0 = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item_v0); num_refs = btrfs_extent_refs_v0(l, ei0); /* FIXME: this isn't correct for data */ extent_flags = BTRFS_BLOCK_FLAG_FULL_BACKREF; #else BUG(); #endif } item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item); if (refs) *refs = num_refs; if (flags) *flags = extent_flags; out: btrfs_free_path(path); return ret; } int btrfs_set_block_flags(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 bytenr, int level, u64 flags) { struct btrfs_path *path; int ret; struct btrfs_key key; struct extent_buffer *l; struct btrfs_extent_item *item; u32 item_size; int skinny_metadata = btrfs_fs_incompat(root->fs_info, BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA); path = btrfs_alloc_path(); if (!path) return -ENOMEM; path->reada = 1; key.objectid = bytenr; if (skinny_metadata) { key.offset = level; key.type = BTRFS_METADATA_ITEM_KEY; } else { key.offset = root->leafsize; key.type = BTRFS_EXTENT_ITEM_KEY; } again: ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path, 0, 0); if (ret < 0) goto out; if (ret > 0 && skinny_metadata) { skinny_metadata = 0; if (path->slots[0]) { path->slots[0]--; btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); if (key.objectid == bytenr && key.offset == root->leafsize && key.type == BTRFS_EXTENT_ITEM_KEY) ret = 0; } if (ret) { btrfs_release_path(path); key.offset = root->leafsize; key.type = BTRFS_EXTENT_ITEM_KEY; goto again; } } if (ret != 0) { btrfs_print_leaf(root, path->nodes[0]); printk("failed to find block number %Lu\n", (unsigned long long)bytenr); BUG(); } l = path->nodes[0]; item_size = btrfs_item_size_nr(l, path->slots[0]); #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 if (item_size < sizeof(*item)) { ret = convert_extent_item_v0(trans, root->fs_info->extent_root, path, (u64)-1, 0); if (ret < 0) goto out; l = path->nodes[0]; item_size = btrfs_item_size_nr(l, path->slots[0]); } #endif BUG_ON(item_size < sizeof(*item)); item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item); flags |= btrfs_extent_flags(l, item); btrfs_set_extent_flags(l, item, flags); out: btrfs_free_path(path); finish_current_insert(trans, root->fs_info->extent_root); del_pending_extents(trans, root->fs_info->extent_root); return ret; } static int __btrfs_mod_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct extent_buffer *buf, int record_parent, int inc) { u64 bytenr; u64 num_bytes; u64 parent; u64 ref_root; u32 nritems; struct btrfs_key key; struct btrfs_file_extent_item *fi; int i; int level; int ret = 0; int (*process_func)(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64, u64, u64, u64, u64, u64); ref_root = btrfs_header_owner(buf); nritems = btrfs_header_nritems(buf); level = btrfs_header_level(buf); if (!root->ref_cows && level == 0) return 0; if (inc) process_func = btrfs_inc_extent_ref; else process_func = btrfs_free_extent; if (record_parent) parent = buf->start; else parent = 0; for (i = 0; i < nritems; i++) { cond_resched(); if (level == 0) { btrfs_item_key_to_cpu(buf, &key, i); if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) continue; fi = btrfs_item_ptr(buf, i, struct btrfs_file_extent_item); if (btrfs_file_extent_type(buf, fi) == BTRFS_FILE_EXTENT_INLINE) continue; bytenr = btrfs_file_extent_disk_bytenr(buf, fi); if (bytenr == 0) continue; num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi); key.offset -= btrfs_file_extent_offset(buf, fi); ret = process_func(trans, root, bytenr, num_bytes, parent, ref_root, key.objectid, key.offset); if (ret) { WARN_ON(1); goto fail; } } else { bytenr = btrfs_node_blockptr(buf, i); num_bytes = btrfs_level_size(root, level - 1); ret = process_func(trans, root, bytenr, num_bytes, parent, ref_root, level - 1, 0); if (ret) { WARN_ON(1); goto fail; } } } return 0; fail: WARN_ON(1); return ret; } int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct extent_buffer *buf, int record_parent) { return __btrfs_mod_ref(trans, root, buf, record_parent, 1); } int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct extent_buffer *buf, int record_parent) { return __btrfs_mod_ref(trans, root, buf, record_parent, 0); } static int write_one_cache_group(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, struct btrfs_block_group_cache *cache) { int ret; int pending_ret; struct btrfs_root *extent_root = root->fs_info->extent_root; unsigned long bi; struct extent_buffer *leaf; ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1); if (ret < 0) goto fail; BUG_ON(ret); leaf = path->nodes[0]; bi = btrfs_item_ptr_offset(leaf, path->slots[0]); write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item)); btrfs_mark_buffer_dirty(leaf); btrfs_release_path(path); fail: finish_current_insert(trans, extent_root); pending_ret = del_pending_extents(trans, extent_root); if (ret) return ret; if (pending_ret) return pending_ret; return 0; } int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans, struct btrfs_root *root) { struct extent_io_tree *block_group_cache; struct btrfs_block_group_cache *cache; int ret; struct btrfs_path *path; u64 last = 0; u64 start; u64 end; u64 ptr; block_group_cache = &root->fs_info->block_group_cache; path = btrfs_alloc_path(); if (!path) return -ENOMEM; while(1) { ret = find_first_extent_bit(block_group_cache, last, &start, &end, BLOCK_GROUP_DIRTY); if (ret) { if (last == 0) break; last = 0; continue; } last = end + 1; ret = get_state_private(block_group_cache, start, &ptr); BUG_ON(ret); clear_extent_bits(block_group_cache, start, end, BLOCK_GROUP_DIRTY, GFP_NOFS); cache = (struct btrfs_block_group_cache *)(unsigned long)ptr; ret = write_one_cache_group(trans, root, path, cache); } btrfs_free_path(path); return 0; } static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info, u64 flags) { struct btrfs_space_info *found; flags &= BTRFS_BLOCK_GROUP_TYPE_MASK; list_for_each_entry(found, &info->space_info, list) { if (found->flags & flags) return found; } return NULL; } static int update_space_info(struct btrfs_fs_info *info, u64 flags, u64 total_bytes, u64 bytes_used, struct btrfs_space_info **space_info) { struct btrfs_space_info *found; found = __find_space_info(info, flags); if (found) { found->total_bytes += total_bytes; found->bytes_used += bytes_used; if (found->total_bytes < found->bytes_used) { fprintf(stderr, "warning, bad space info total_bytes " "%llu used %llu\n", (unsigned long long)found->total_bytes, (unsigned long long)found->bytes_used); } *space_info = found; return 0; } found = kmalloc(sizeof(*found), GFP_NOFS); if (!found) return -ENOMEM; list_add(&found->list, &info->space_info); found->flags = flags & BTRFS_BLOCK_GROUP_TYPE_MASK; found->total_bytes = total_bytes; found->bytes_used = bytes_used; found->bytes_pinned = 0; found->full = 0; *space_info = found; return 0; } static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags) { u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10 | BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6 | BTRFS_BLOCK_GROUP_DUP); if (extra_flags) { if (flags & BTRFS_BLOCK_GROUP_DATA) fs_info->avail_data_alloc_bits |= extra_flags; if (flags & BTRFS_BLOCK_GROUP_METADATA) fs_info->avail_metadata_alloc_bits |= extra_flags; if (flags & BTRFS_BLOCK_GROUP_SYSTEM) fs_info->avail_system_alloc_bits |= extra_flags; } } static int do_chunk_alloc(struct btrfs_trans_handle *trans, struct btrfs_root *extent_root, u64 alloc_bytes, u64 flags) { struct btrfs_space_info *space_info; u64 thresh; u64 start; u64 num_bytes; int ret; space_info = __find_space_info(extent_root->fs_info, flags); if (!space_info) { ret = update_space_info(extent_root->fs_info, flags, 0, 0, &space_info); BUG_ON(ret); } BUG_ON(!space_info); if (space_info->full) return 0; thresh = div_factor(space_info->total_bytes, 7); if ((space_info->bytes_used + space_info->bytes_pinned + alloc_bytes) < thresh) return 0; ret = btrfs_alloc_chunk(trans, extent_root, &start, &num_bytes, space_info->flags); if (ret == -ENOSPC) { space_info->full = 1; return 0; } BUG_ON(ret); ret = btrfs_make_block_group(trans, extent_root, 0, space_info->flags, BTRFS_FIRST_CHUNK_TREE_OBJECTID, start, num_bytes); BUG_ON(ret); return 0; } static int update_block_group(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 bytenr, u64 num_bytes, int alloc, int mark_free) { struct btrfs_block_group_cache *cache; struct btrfs_fs_info *info = root->fs_info; u64 total = num_bytes; u64 old_val; u64 byte_in_group; u64 start; u64 end; /* block accounting for super block */ old_val = btrfs_super_bytes_used(info->super_copy); if (alloc) old_val += num_bytes; else old_val -= num_bytes; btrfs_set_super_bytes_used(info->super_copy, old_val); /* block accounting for root item */ old_val = btrfs_root_used(&root->root_item); if (alloc) old_val += num_bytes; else old_val -= num_bytes; btrfs_set_root_used(&root->root_item, old_val); while(total) { cache = btrfs_lookup_block_group(info, bytenr); if (!cache) { return -1; } byte_in_group = bytenr - cache->key.objectid; WARN_ON(byte_in_group > cache->key.offset); start = cache->key.objectid; end = start + cache->key.offset - 1; set_extent_bits(&info->block_group_cache, start, end, BLOCK_GROUP_DIRTY, GFP_NOFS); old_val = btrfs_block_group_used(&cache->item); num_bytes = min(total, cache->key.offset - byte_in_group); if (alloc) { old_val += num_bytes; cache->space_info->bytes_used += num_bytes; } else { old_val -= num_bytes; cache->space_info->bytes_used -= num_bytes; if (mark_free) { set_extent_dirty(&info->free_space_cache, bytenr, bytenr + num_bytes - 1, GFP_NOFS); } } btrfs_set_block_group_used(&cache->item, old_val); total -= num_bytes; bytenr += num_bytes; } return 0; } static int update_pinned_extents(struct btrfs_root *root, u64 bytenr, u64 num, int pin) { u64 len; struct btrfs_block_group_cache *cache; struct btrfs_fs_info *fs_info = root->fs_info; if (pin) { set_extent_dirty(&fs_info->pinned_extents, bytenr, bytenr + num - 1, GFP_NOFS); } else { clear_extent_dirty(&fs_info->pinned_extents, bytenr, bytenr + num - 1, GFP_NOFS); } while (num > 0) { cache = btrfs_lookup_block_group(fs_info, bytenr); if (!cache) { len = min((u64)root->sectorsize, num); goto next; } WARN_ON(!cache); len = min(num, cache->key.offset - (bytenr - cache->key.objectid)); if (pin) { cache->pinned += len; cache->space_info->bytes_pinned += len; fs_info->total_pinned += len; } else { cache->pinned -= len; cache->space_info->bytes_pinned -= len; fs_info->total_pinned -= len; } next: bytenr += len; num -= len; } return 0; } int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct extent_io_tree *unpin) { u64 start; u64 end; int ret; struct extent_io_tree *free_space_cache; free_space_cache = &root->fs_info->free_space_cache; while(1) { ret = find_first_extent_bit(unpin, 0, &start, &end, EXTENT_DIRTY); if (ret) break; update_pinned_extents(root, start, end + 1 - start, 0); clear_extent_dirty(unpin, start, end, GFP_NOFS); set_extent_dirty(free_space_cache, start, end, GFP_NOFS); } return 0; } static int extent_root_pending_ops(struct btrfs_fs_info *info) { u64 start; u64 end; int ret; ret = find_first_extent_bit(&info->extent_ins, 0, &start, &end, EXTENT_LOCKED); if (!ret) { ret = find_first_extent_bit(&info->pending_del, 0, &start, &end, EXTENT_LOCKED); } return ret == 0; } static int finish_current_insert(struct btrfs_trans_handle *trans, struct btrfs_root *extent_root) { u64 start; u64 end; u64 priv; struct btrfs_fs_info *info = extent_root->fs_info; struct pending_extent_op *extent_op; struct btrfs_key key; int ret; int skinny_metadata = btrfs_fs_incompat(extent_root->fs_info, BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA); while(1) { ret = find_first_extent_bit(&info->extent_ins, 0, &start, &end, EXTENT_LOCKED); if (ret) break; ret = get_state_private(&info->extent_ins, start, &priv); BUG_ON(ret); extent_op = (struct pending_extent_op *)(unsigned long)priv; if (extent_op->type == PENDING_EXTENT_INSERT) { key.objectid = start; if (skinny_metadata) { key.offset = extent_op->level; key.type = BTRFS_METADATA_ITEM_KEY; } else { key.offset = extent_op->num_bytes; key.type = BTRFS_EXTENT_ITEM_KEY; } ret = alloc_reserved_tree_block(trans, extent_root, extent_root->root_key.objectid, trans->transid, extent_op->flags, &extent_op->key, extent_op->level, &key); BUG_ON(ret); } else { BUG_ON(1); } clear_extent_bits(&info->extent_ins, start, end, EXTENT_LOCKED, GFP_NOFS); kfree(extent_op); } return 0; } static int pin_down_bytes(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 bytenr, u64 num_bytes, int is_data) { int err = 0; struct extent_buffer *buf; if (is_data) goto pinit; buf = btrfs_find_tree_block(root, bytenr, num_bytes); if (!buf) goto pinit; /* we can reuse a block if it hasn't been written * and it is from this transaction. We can't * reuse anything from the tree log root because * it has tiny sub-transactions. */ if (btrfs_buffer_uptodate(buf, 0)) { u64 header_owner = btrfs_header_owner(buf); u64 header_transid = btrfs_header_generation(buf); if (header_owner != BTRFS_TREE_LOG_OBJECTID && header_transid == trans->transid && !btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) { clean_tree_block(NULL, root, buf); free_extent_buffer(buf); return 1; } } free_extent_buffer(buf); pinit: update_pinned_extents(root, bytenr, num_bytes, 1); BUG_ON(err < 0); return 0; } void btrfs_pin_extent(struct btrfs_fs_info *fs_info, u64 bytenr, u64 num_bytes) { update_pinned_extents(fs_info->extent_root, bytenr, num_bytes, 1); } void btrfs_unpin_extent(struct btrfs_fs_info *fs_info, u64 bytenr, u64 num_bytes) { update_pinned_extents(fs_info->extent_root, bytenr, num_bytes, 0); } /* * remove an extent from the root, returns 0 on success */ static int __free_extent(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 bytenr, u64 num_bytes, u64 parent, u64 root_objectid, u64 owner_objectid, u64 owner_offset, int refs_to_drop) { struct btrfs_key key; struct btrfs_path *path; struct btrfs_extent_ops *ops = root->fs_info->extent_ops; struct btrfs_root *extent_root = root->fs_info->extent_root; struct extent_buffer *leaf; struct btrfs_extent_item *ei; struct btrfs_extent_inline_ref *iref; int ret; int is_data; int extent_slot = 0; int found_extent = 0; int num_to_del = 1; u32 item_size; u64 refs; int skinny_metadata = btrfs_fs_incompat(extent_root->fs_info, BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA); if (root->fs_info->free_extent_hook) { root->fs_info->free_extent_hook(trans, root, bytenr, num_bytes, parent, root_objectid, owner_objectid, owner_offset, refs_to_drop); } path = btrfs_alloc_path(); if (!path) return -ENOMEM; path->reada = 1; is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID; if (is_data) skinny_metadata = 0; BUG_ON(!is_data && refs_to_drop != 1); ret = lookup_extent_backref(trans, extent_root, path, &iref, bytenr, num_bytes, parent, root_objectid, owner_objectid, owner_offset); if (ret == 0) { extent_slot = path->slots[0]; while (extent_slot >= 0) { btrfs_item_key_to_cpu(path->nodes[0], &key, extent_slot); if (key.objectid != bytenr) break; if (key.type == BTRFS_EXTENT_ITEM_KEY && key.offset == num_bytes) { found_extent = 1; break; } if (key.type == BTRFS_METADATA_ITEM_KEY && key.offset == owner_objectid) { found_extent = 1; break; } if (path->slots[0] - extent_slot > 5) break; extent_slot--; } #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 item_size = btrfs_item_size_nr(path->nodes[0], extent_slot); if (found_extent && item_size < sizeof(*ei)) found_extent = 0; #endif if (!found_extent) { BUG_ON(iref); ret = remove_extent_backref(trans, extent_root, path, NULL, refs_to_drop, is_data); BUG_ON(ret); btrfs_release_path(path); key.objectid = bytenr; if (skinny_metadata) { key.type = BTRFS_METADATA_ITEM_KEY; key.offset = owner_objectid; } else { key.type = BTRFS_EXTENT_ITEM_KEY; key.offset = num_bytes; } ret = btrfs_search_slot(trans, extent_root, &key, path, -1, 1); if (ret > 0 && skinny_metadata && path->slots[0]) { path->slots[0]--; btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); if (key.objectid == bytenr && key.type == BTRFS_EXTENT_ITEM_KEY && key.offset == num_bytes) ret = 0; } if (ret > 0 && skinny_metadata) { skinny_metadata = 0; btrfs_release_path(path); key.type = BTRFS_EXTENT_ITEM_KEY; key.offset = num_bytes; ret = btrfs_search_slot(trans, extent_root, &key, path, -1, 1); } if (ret) { printk(KERN_ERR "umm, got %d back from search" ", was looking for %llu\n", ret, (unsigned long long)bytenr); btrfs_print_leaf(extent_root, path->nodes[0]); } BUG_ON(ret); extent_slot = path->slots[0]; } } else { printk(KERN_ERR "btrfs unable to find ref byte nr %llu " "parent %llu root %llu owner %llu offset %llu\n", (unsigned long long)bytenr, (unsigned long long)parent, (unsigned long long)root_objectid, (unsigned long long)owner_objectid, (unsigned long long)owner_offset); ret = -EIO; goto fail; } leaf = path->nodes[0]; item_size = btrfs_item_size_nr(leaf, extent_slot); #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 if (item_size < sizeof(*ei)) { BUG_ON(found_extent || extent_slot != path->slots[0]); ret = convert_extent_item_v0(trans, extent_root, path, owner_objectid, 0); BUG_ON(ret < 0); btrfs_release_path(path); key.objectid = bytenr; key.type = BTRFS_EXTENT_ITEM_KEY; key.offset = num_bytes; ret = btrfs_search_slot(trans, extent_root, &key, path, -1, 1); if (ret) { printk(KERN_ERR "umm, got %d back from search" ", was looking for %llu\n", ret, (unsigned long long)bytenr); btrfs_print_leaf(extent_root, path->nodes[0]); } BUG_ON(ret); extent_slot = path->slots[0]; leaf = path->nodes[0]; item_size = btrfs_item_size_nr(leaf, extent_slot); } #endif BUG_ON(item_size < sizeof(*ei)); ei = btrfs_item_ptr(leaf, extent_slot, struct btrfs_extent_item); if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID && key.type == BTRFS_EXTENT_ITEM_KEY) { struct btrfs_tree_block_info *bi; BUG_ON(item_size < sizeof(*ei) + sizeof(*bi)); bi = (struct btrfs_tree_block_info *)(ei + 1); WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi)); } refs = btrfs_extent_refs(leaf, ei); BUG_ON(refs < refs_to_drop); refs -= refs_to_drop; if (refs > 0) { /* * In the case of inline back ref, reference count will * be updated by remove_extent_backref */ if (iref) { BUG_ON(!found_extent); } else { btrfs_set_extent_refs(leaf, ei, refs); btrfs_mark_buffer_dirty(leaf); } if (found_extent) { ret = remove_extent_backref(trans, extent_root, path, iref, refs_to_drop, is_data); BUG_ON(ret); } } else { int mark_free = 0; int pin = 1; if (found_extent) { BUG_ON(is_data && refs_to_drop != extent_data_ref_count(root, path, iref)); if (iref) { BUG_ON(path->slots[0] != extent_slot); } else { BUG_ON(path->slots[0] != extent_slot + 1); path->slots[0] = extent_slot; num_to_del = 2; } } if (ops && ops->free_extent) { ret = ops->free_extent(root, bytenr, num_bytes); if (ret > 0) { pin = 0; mark_free = 0; } } if (pin) { ret = pin_down_bytes(trans, root, bytenr, num_bytes, is_data); if (ret > 0) mark_free = 1; BUG_ON(ret < 0); } ret = btrfs_del_items(trans, extent_root, path, path->slots[0], num_to_del); BUG_ON(ret); btrfs_release_path(path); if (is_data) { ret = btrfs_del_csums(trans, root, bytenr, num_bytes); BUG_ON(ret); } update_block_group(trans, root, bytenr, num_bytes, 0, mark_free); } fail: btrfs_free_path(path); finish_current_insert(trans, extent_root); return ret; } /* * find all the blocks marked as pending in the radix tree and remove * them from the extent map */ static int del_pending_extents(struct btrfs_trans_handle *trans, struct btrfs_root *extent_root) { int ret; int err = 0; u64 start; u64 end; u64 priv; struct extent_io_tree *pending_del; struct extent_io_tree *extent_ins; struct pending_extent_op *extent_op; extent_ins = &extent_root->fs_info->extent_ins; pending_del = &extent_root->fs_info->pending_del; while(1) { ret = find_first_extent_bit(pending_del, 0, &start, &end, EXTENT_LOCKED); if (ret) break; ret = get_state_private(pending_del, start, &priv); BUG_ON(ret); extent_op = (struct pending_extent_op *)(unsigned long)priv; clear_extent_bits(pending_del, start, end, EXTENT_LOCKED, GFP_NOFS); if (!test_range_bit(extent_ins, start, end, EXTENT_LOCKED, 0)) { ret = __free_extent(trans, extent_root, start, end + 1 - start, 0, extent_root->root_key.objectid, extent_op->level, 0, 1); kfree(extent_op); } else { kfree(extent_op); ret = get_state_private(extent_ins, start, &priv); BUG_ON(ret); extent_op = (struct pending_extent_op *) (unsigned long)priv; clear_extent_bits(extent_ins, start, end, EXTENT_LOCKED, GFP_NOFS); if (extent_op->type == PENDING_BACKREF_UPDATE) BUG_ON(1); kfree(extent_op); } if (ret) err = ret; } return err; } /* * remove an extent from the root, returns 0 on success */ int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 bytenr, u64 num_bytes, u64 parent, u64 root_objectid, u64 owner, u64 offset) { struct btrfs_root *extent_root = root->fs_info->extent_root; int pending_ret; int ret; WARN_ON(num_bytes < root->sectorsize); if (root == extent_root) { struct pending_extent_op *extent_op; extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS); BUG_ON(!extent_op); extent_op->type = PENDING_EXTENT_DELETE; extent_op->bytenr = bytenr; extent_op->num_bytes = num_bytes; extent_op->level = (int)owner; set_extent_bits(&root->fs_info->pending_del, bytenr, bytenr + num_bytes - 1, EXTENT_LOCKED, GFP_NOFS); set_state_private(&root->fs_info->pending_del, bytenr, (unsigned long)extent_op); return 0; } ret = __free_extent(trans, root, bytenr, num_bytes, parent, root_objectid, owner, offset, 1); pending_ret = del_pending_extents(trans, root->fs_info->extent_root); return ret ? ret : pending_ret; } static u64 stripe_align(struct btrfs_root *root, u64 val) { u64 mask = ((u64)root->stripesize - 1); u64 ret = (val + mask) & ~mask; return ret; } /* * walks the btree of allocated extents and find a hole of a given size. * The key ins is changed to record the hole: * ins->objectid == block start * ins->flags = BTRFS_EXTENT_ITEM_KEY * ins->offset == number of blocks * Any available blocks before search_start are skipped. */ static int noinline find_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root *orig_root, u64 num_bytes, u64 empty_size, u64 search_start, u64 search_end, u64 hint_byte, struct btrfs_key *ins, u64 exclude_start, u64 exclude_nr, int data) { int ret; u64 orig_search_start = search_start; struct btrfs_root * root = orig_root->fs_info->extent_root; struct btrfs_fs_info *info = root->fs_info; u64 total_needed = num_bytes; struct btrfs_block_group_cache *block_group; int full_scan = 0; int wrapped = 0; WARN_ON(num_bytes < root->sectorsize); btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY); search_start = stripe_align(root, search_start); if (hint_byte) { block_group = btrfs_lookup_first_block_group(info, hint_byte); if (!block_group) hint_byte = search_start; block_group = btrfs_find_block_group(root, block_group, hint_byte, data, 1); } else { block_group = btrfs_find_block_group(root, trans->block_group, search_start, data, 1); } total_needed += empty_size; check_failed: search_start = stripe_align(root, search_start); if (!block_group) { block_group = btrfs_lookup_first_block_group(info, search_start); if (!block_group) block_group = btrfs_lookup_first_block_group(info, orig_search_start); } ret = find_search_start(root, &block_group, &search_start, total_needed, data); if (ret) goto new_group; ins->objectid = search_start; ins->offset = num_bytes; if (ins->objectid + num_bytes > block_group->key.objectid + block_group->key.offset) { search_start = block_group->key.objectid + block_group->key.offset; goto new_group; } if (test_range_bit(&info->extent_ins, ins->objectid, ins->objectid + num_bytes -1, EXTENT_LOCKED, 0)) { search_start = ins->objectid + num_bytes; goto new_group; } if (test_range_bit(&info->pinned_extents, ins->objectid, ins->objectid + num_bytes -1, EXTENT_DIRTY, 0)) { search_start = ins->objectid + num_bytes; goto new_group; } if (exclude_nr > 0 && (ins->objectid + num_bytes > exclude_start && ins->objectid < exclude_start + exclude_nr)) { search_start = exclude_start + exclude_nr; goto new_group; } if (!(data & BTRFS_BLOCK_GROUP_DATA)) { block_group = btrfs_lookup_block_group(info, ins->objectid); if (block_group) trans->block_group = block_group; } ins->offset = num_bytes; return 0; new_group: block_group = btrfs_lookup_first_block_group(info, search_start); if (!block_group) { search_start = orig_search_start; if (full_scan) { ret = -ENOSPC; goto error; } if (wrapped) { if (!full_scan) total_needed -= empty_size; full_scan = 1; } else wrapped = 1; } cond_resched(); block_group = btrfs_find_block_group(root, block_group, search_start, data, 0); goto check_failed; error: return ret; } int btrfs_reserve_extent(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 num_bytes, u64 empty_size, u64 hint_byte, u64 search_end, struct btrfs_key *ins, int data) { int ret; u64 search_start = 0; u64 alloc_profile; struct btrfs_fs_info *info = root->fs_info; if (info->extent_ops) { struct btrfs_extent_ops *ops = info->extent_ops; ret = ops->alloc_extent(root, num_bytes, hint_byte, ins); BUG_ON(ret); goto found; } if (data) { alloc_profile = info->avail_data_alloc_bits & info->data_alloc_profile; data = BTRFS_BLOCK_GROUP_DATA | alloc_profile; } else if ((info->system_allocs > 0 || root == info->chunk_root) && info->system_allocs >= 0) { alloc_profile = info->avail_system_alloc_bits & info->system_alloc_profile; data = BTRFS_BLOCK_GROUP_SYSTEM | alloc_profile; } else { alloc_profile = info->avail_metadata_alloc_bits & info->metadata_alloc_profile; data = BTRFS_BLOCK_GROUP_METADATA | alloc_profile; } if (root->ref_cows) { if (!(data & BTRFS_BLOCK_GROUP_METADATA)) { ret = do_chunk_alloc(trans, root->fs_info->extent_root, num_bytes, BTRFS_BLOCK_GROUP_METADATA); BUG_ON(ret); } ret = do_chunk_alloc(trans, root->fs_info->extent_root, num_bytes + 2 * 1024 * 1024, data); BUG_ON(ret); } WARN_ON(num_bytes < root->sectorsize); ret = find_free_extent(trans, root, num_bytes, empty_size, search_start, search_end, hint_byte, ins, trans->alloc_exclude_start, trans->alloc_exclude_nr, data); BUG_ON(ret); found: clear_extent_dirty(&root->fs_info->free_space_cache, ins->objectid, ins->objectid + ins->offset - 1, GFP_NOFS); return ret; } static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 root_objectid, u64 generation, u64 flags, struct btrfs_disk_key *key, int level, struct btrfs_key *ins) { int ret; struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_extent_item *extent_item; struct btrfs_tree_block_info *block_info; struct btrfs_extent_inline_ref *iref; struct btrfs_path *path; struct extent_buffer *leaf; u32 size = sizeof(*extent_item) + sizeof(*iref); int skinny_metadata = btrfs_fs_incompat(fs_info, BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA); if (!skinny_metadata) size += sizeof(*block_info); path = btrfs_alloc_path(); BUG_ON(!path); ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path, ins, size); BUG_ON(ret); leaf = path->nodes[0]; extent_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item); btrfs_set_extent_refs(leaf, extent_item, 1); btrfs_set_extent_generation(leaf, extent_item, generation); btrfs_set_extent_flags(leaf, extent_item, flags | BTRFS_EXTENT_FLAG_TREE_BLOCK); if (skinny_metadata) { iref = (struct btrfs_extent_inline_ref *)(extent_item + 1); } else { block_info = (struct btrfs_tree_block_info *)(extent_item + 1); btrfs_set_tree_block_key(leaf, block_info, key); btrfs_set_tree_block_level(leaf, block_info, level); iref = (struct btrfs_extent_inline_ref *)(block_info + 1); } btrfs_set_extent_inline_ref_type(leaf, iref, BTRFS_TREE_BLOCK_REF_KEY); btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid); btrfs_mark_buffer_dirty(leaf); btrfs_free_path(path); ret = update_block_group(trans, root, ins->objectid, root->leafsize, 1, 0); return ret; } static int alloc_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 num_bytes, u64 root_objectid, u64 generation, u64 flags, struct btrfs_disk_key *key, int level, u64 empty_size, u64 hint_byte, u64 search_end, struct btrfs_key *ins) { int ret; ret = btrfs_reserve_extent(trans, root, num_bytes, empty_size, hint_byte, search_end, ins, 0); BUG_ON(ret); if (root_objectid == BTRFS_EXTENT_TREE_OBJECTID) { struct pending_extent_op *extent_op; extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS); BUG_ON(!extent_op); extent_op->type = PENDING_EXTENT_INSERT; extent_op->bytenr = ins->objectid; extent_op->num_bytes = ins->offset; extent_op->level = level; extent_op->flags = flags; memcpy(&extent_op->key, key, sizeof(*key)); set_extent_bits(&root->fs_info->extent_ins, ins->objectid, ins->objectid + ins->offset - 1, EXTENT_LOCKED, GFP_NOFS); set_state_private(&root->fs_info->extent_ins, ins->objectid, (unsigned long)extent_op); } else { if (btrfs_fs_incompat(root->fs_info, BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA)) { ins->offset = level; ins->type = BTRFS_METADATA_ITEM_KEY; } ret = alloc_reserved_tree_block(trans, root, root_objectid, generation, flags, key, level, ins); finish_current_insert(trans, root->fs_info->extent_root); del_pending_extents(trans, root->fs_info->extent_root); } return ret; } /* * helper function to allocate a block for a given tree * returns the tree buffer or NULL. */ struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans, struct btrfs_root *root, u32 blocksize, u64 root_objectid, struct btrfs_disk_key *key, int level, u64 hint, u64 empty_size) { struct btrfs_key ins; int ret; struct extent_buffer *buf; ret = alloc_tree_block(trans, root, blocksize, root_objectid, trans->transid, 0, key, level, empty_size, hint, (u64)-1, &ins); if (ret) { BUG_ON(ret > 0); return ERR_PTR(ret); } buf = btrfs_find_create_tree_block(root, ins.objectid, blocksize); if (!buf) { btrfs_free_extent(trans, root, ins.objectid, ins.offset, 0, root->root_key.objectid, level, 0); BUG_ON(1); return ERR_PTR(-ENOMEM); } btrfs_set_buffer_uptodate(buf); trans->blocks_used++; return buf; } #if 0 static int noinline drop_leaf_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct extent_buffer *leaf) { u64 leaf_owner; u64 leaf_generation; struct btrfs_key key; struct btrfs_file_extent_item *fi; int i; int nritems; int ret; BUG_ON(!btrfs_is_leaf(leaf)); nritems = btrfs_header_nritems(leaf); leaf_owner = btrfs_header_owner(leaf); leaf_generation = btrfs_header_generation(leaf); for (i = 0; i < nritems; i++) { u64 disk_bytenr; btrfs_item_key_to_cpu(leaf, &key, i); if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) continue; fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item); if (btrfs_file_extent_type(leaf, fi) == BTRFS_FILE_EXTENT_INLINE) continue; /* * FIXME make sure to insert a trans record that * repeats the snapshot del on crash */ disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); if (disk_bytenr == 0) continue; ret = btrfs_free_extent(trans, root, disk_bytenr, btrfs_file_extent_disk_num_bytes(leaf, fi), leaf->start, leaf_owner, leaf_generation, key.objectid, 0); BUG_ON(ret); } return 0; } static void noinline reada_walk_down(struct btrfs_root *root, struct extent_buffer *node, int slot) { u64 bytenr; u64 last = 0; u32 nritems; u32 refs; u32 blocksize; int ret; int i; int level; int skipped = 0; nritems = btrfs_header_nritems(node); level = btrfs_header_level(node); if (level) return; for (i = slot; i < nritems && skipped < 32; i++) { bytenr = btrfs_node_blockptr(node, i); if (last && ((bytenr > last && bytenr - last > 32 * 1024) || (last > bytenr && last - bytenr > 32 * 1024))) { skipped++; continue; } blocksize = btrfs_level_size(root, level - 1); if (i != slot) { ret = btrfs_lookup_extent_ref(NULL, root, bytenr, blocksize, &refs); BUG_ON(ret); if (refs != 1) { skipped++; continue; } } mutex_unlock(&root->fs_info->fs_mutex); ret = readahead_tree_block(root, bytenr, blocksize, btrfs_node_ptr_generation(node, i)); last = bytenr + blocksize; cond_resched(); mutex_lock(&root->fs_info->fs_mutex); if (ret) break; } } /* * helper function for drop_snapshot, this walks down the tree dropping ref * counts as it goes. */ static int noinline walk_down_tree(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, int *level) { u64 root_owner; u64 root_gen; u64 bytenr; u64 ptr_gen; struct extent_buffer *next; struct extent_buffer *cur; struct extent_buffer *parent; u32 blocksize; int ret; u32 refs; WARN_ON(*level < 0); WARN_ON(*level >= BTRFS_MAX_LEVEL); ret = btrfs_lookup_extent_ref(trans, root, path->nodes[*level]->start, path->nodes[*level]->len, &refs); BUG_ON(ret); if (refs > 1) goto out; /* * walk down to the last node level and free all the leaves */ while(*level >= 0) { WARN_ON(*level < 0); WARN_ON(*level >= BTRFS_MAX_LEVEL); cur = path->nodes[*level]; if (btrfs_header_level(cur) != *level) WARN_ON(1); if (path->slots[*level] >= btrfs_header_nritems(cur)) break; if (*level == 0) { ret = drop_leaf_ref(trans, root, cur); BUG_ON(ret); break; } bytenr = btrfs_node_blockptr(cur, path->slots[*level]); ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]); blocksize = btrfs_level_size(root, *level - 1); ret = btrfs_lookup_extent_ref(trans, root, bytenr, blocksize, &refs); BUG_ON(ret); if (refs != 1) { parent = path->nodes[*level]; root_owner = btrfs_header_owner(parent); root_gen = btrfs_header_generation(parent); path->slots[*level]++; ret = btrfs_free_extent(trans, root, bytenr, blocksize, parent->start, root_owner, root_gen, *level - 1, 1); BUG_ON(ret); continue; } next = btrfs_find_tree_block(root, bytenr, blocksize); if (!next || !btrfs_buffer_uptodate(next, ptr_gen)) { free_extent_buffer(next); reada_walk_down(root, cur, path->slots[*level]); mutex_unlock(&root->fs_info->fs_mutex); next = read_tree_block(root, bytenr, blocksize, ptr_gen); mutex_lock(&root->fs_info->fs_mutex); if (!extent_buffer_uptodate(next)) { if (IS_ERR(next)) ret = PTR_ERR(next); else ret = -EIO; break; } } WARN_ON(*level <= 0); if (path->nodes[*level-1]) free_extent_buffer(path->nodes[*level-1]); path->nodes[*level-1] = next; *level = btrfs_header_level(next); path->slots[*level] = 0; } out: WARN_ON(*level < 0); WARN_ON(*level >= BTRFS_MAX_LEVEL); if (path->nodes[*level] == root->node) { root_owner = root->root_key.objectid; parent = path->nodes[*level]; } else { parent = path->nodes[*level + 1]; root_owner = btrfs_header_owner(parent); } root_gen = btrfs_header_generation(parent); ret = btrfs_free_extent(trans, root, path->nodes[*level]->start, path->nodes[*level]->len, parent->start, root_owner, root_gen, *level, 1); free_extent_buffer(path->nodes[*level]); path->nodes[*level] = NULL; *level += 1; BUG_ON(ret); return 0; } /* * helper for dropping snapshots. This walks back up the tree in the path * to find the first node higher up where we haven't yet gone through * all the slots */ static int noinline walk_up_tree(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, int *level) { u64 root_owner; u64 root_gen; struct btrfs_root_item *root_item = &root->root_item; int i; int slot; int ret; for(i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) { slot = path->slots[i]; if (slot < btrfs_header_nritems(path->nodes[i]) - 1) { struct extent_buffer *node; struct btrfs_disk_key disk_key; node = path->nodes[i]; path->slots[i]++; *level = i; WARN_ON(*level == 0); btrfs_node_key(node, &disk_key, path->slots[i]); memcpy(&root_item->drop_progress, &disk_key, sizeof(disk_key)); root_item->drop_level = i; return 0; } else { struct extent_buffer *parent; if (path->nodes[*level] == root->node) parent = path->nodes[*level]; else parent = path->nodes[*level + 1]; root_owner = btrfs_header_owner(parent); root_gen = btrfs_header_generation(parent); ret = btrfs_free_extent(trans, root, path->nodes[*level]->start, path->nodes[*level]->len, parent->start, root_owner, root_gen, *level, 1); BUG_ON(ret); free_extent_buffer(path->nodes[*level]); path->nodes[*level] = NULL; *level = i + 1; } } return 1; } #endif int btrfs_free_block_groups(struct btrfs_fs_info *info) { struct btrfs_space_info *sinfo; struct btrfs_block_group_cache *cache; u64 start; u64 end; u64 ptr; int ret; while(1) { ret = find_first_extent_bit(&info->block_group_cache, 0, &start, &end, (unsigned int)-1); if (ret) break; ret = get_state_private(&info->block_group_cache, start, &ptr); if (!ret) { cache = u64_to_ptr(ptr); if (cache->free_space_ctl) { btrfs_remove_free_space_cache(cache); kfree(cache->free_space_ctl); } kfree(cache); } clear_extent_bits(&info->block_group_cache, start, end, (unsigned int)-1, GFP_NOFS); } while(1) { ret = find_first_extent_bit(&info->free_space_cache, 0, &start, &end, EXTENT_DIRTY); if (ret) break; clear_extent_dirty(&info->free_space_cache, start, end, GFP_NOFS); } while (!list_empty(&info->space_info)) { sinfo = list_entry(info->space_info.next, struct btrfs_space_info, list); list_del_init(&sinfo->list); kfree(sinfo); } return 0; } static int find_first_block_group(struct btrfs_root *root, struct btrfs_path *path, struct btrfs_key *key) { int ret; struct btrfs_key found_key; struct extent_buffer *leaf; int slot; ret = btrfs_search_slot(NULL, root, key, path, 0, 0); if (ret < 0) return ret; while(1) { slot = path->slots[0]; leaf = path->nodes[0]; if (slot >= btrfs_header_nritems(leaf)) { ret = btrfs_next_leaf(root, path); if (ret == 0) continue; if (ret < 0) goto error; break; } btrfs_item_key_to_cpu(leaf, &found_key, slot); if (found_key.objectid >= key->objectid && found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) return 0; path->slots[0]++; } ret = -ENOENT; error: return ret; } int btrfs_read_block_groups(struct btrfs_root *root) { struct btrfs_path *path; int ret; int bit; struct btrfs_block_group_cache *cache; struct btrfs_fs_info *info = root->fs_info; struct btrfs_space_info *space_info; struct extent_io_tree *block_group_cache; struct btrfs_key key; struct btrfs_key found_key; struct extent_buffer *leaf; block_group_cache = &info->block_group_cache; root = info->extent_root; key.objectid = 0; key.offset = 0; btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY); path = btrfs_alloc_path(); if (!path) return -ENOMEM; while(1) { ret = find_first_block_group(root, path, &key); if (ret > 0) { ret = 0; goto error; } if (ret != 0) { goto error; } leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); cache = kzalloc(sizeof(*cache), GFP_NOFS); if (!cache) { ret = -ENOMEM; break; } read_extent_buffer(leaf, &cache->item, btrfs_item_ptr_offset(leaf, path->slots[0]), sizeof(cache->item)); memcpy(&cache->key, &found_key, sizeof(found_key)); cache->cached = 0; cache->pinned = 0; key.objectid = found_key.objectid + found_key.offset; btrfs_release_path(path); cache->flags = btrfs_block_group_flags(&cache->item); bit = 0; if (cache->flags & BTRFS_BLOCK_GROUP_DATA) { bit = BLOCK_GROUP_DATA; } else if (cache->flags & BTRFS_BLOCK_GROUP_SYSTEM) { bit = BLOCK_GROUP_SYSTEM; } else if (cache->flags & BTRFS_BLOCK_GROUP_METADATA) { bit = BLOCK_GROUP_METADATA; } set_avail_alloc_bits(info, cache->flags); if (btrfs_chunk_readonly(root, cache->key.objectid)) cache->ro = 1; ret = update_space_info(info, cache->flags, found_key.offset, btrfs_block_group_used(&cache->item), &space_info); BUG_ON(ret); cache->space_info = space_info; /* use EXTENT_LOCKED to prevent merging */ set_extent_bits(block_group_cache, found_key.objectid, found_key.objectid + found_key.offset - 1, bit | EXTENT_LOCKED, GFP_NOFS); set_state_private(block_group_cache, found_key.objectid, (unsigned long)cache); } ret = 0; error: btrfs_free_path(path); return ret; } struct btrfs_block_group_cache * btrfs_add_block_group(struct btrfs_fs_info *fs_info, u64 bytes_used, u64 type, u64 chunk_objectid, u64 chunk_offset, u64 size) { int ret; int bit = 0; struct btrfs_block_group_cache *cache; struct extent_io_tree *block_group_cache; block_group_cache = &fs_info->block_group_cache; cache = kzalloc(sizeof(*cache), GFP_NOFS); BUG_ON(!cache); cache->key.objectid = chunk_offset; cache->key.offset = size; btrfs_set_key_type(&cache->key, BTRFS_BLOCK_GROUP_ITEM_KEY); btrfs_set_block_group_used(&cache->item, bytes_used); btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid); cache->flags = type; btrfs_set_block_group_flags(&cache->item, type); ret = update_space_info(fs_info, cache->flags, size, bytes_used, &cache->space_info); BUG_ON(ret); bit = block_group_state_bits(type); ret = set_extent_bits(block_group_cache, chunk_offset, chunk_offset + size - 1, bit | EXTENT_LOCKED, GFP_NOFS); BUG_ON(ret); ret = set_state_private(block_group_cache, chunk_offset, (unsigned long)cache); BUG_ON(ret); set_avail_alloc_bits(fs_info, type); return cache; } int btrfs_make_block_group(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 bytes_used, u64 type, u64 chunk_objectid, u64 chunk_offset, u64 size) { int ret; struct btrfs_root *extent_root; struct btrfs_block_group_cache *cache; cache = btrfs_add_block_group(root->fs_info, bytes_used, type, chunk_objectid, chunk_offset, size); extent_root = root->fs_info->extent_root; ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item, sizeof(cache->item)); BUG_ON(ret); ret = finish_current_insert(trans, extent_root); BUG_ON(ret); ret = del_pending_extents(trans, extent_root); BUG_ON(ret); return 0; } /* * This is for converter use only. * * In that case, we don't know where are free blocks located. * Therefore all block group cache entries must be setup properly * before doing any block allocation. */ int btrfs_make_block_groups(struct btrfs_trans_handle *trans, struct btrfs_root *root) { u64 total_bytes; u64 cur_start; u64 group_type; u64 group_size; u64 group_align; u64 total_data = 0; u64 total_metadata = 0; u64 chunk_objectid; int ret; int bit; struct btrfs_root *extent_root; struct btrfs_block_group_cache *cache; struct extent_io_tree *block_group_cache; extent_root = root->fs_info->extent_root; block_group_cache = &root->fs_info->block_group_cache; chunk_objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; total_bytes = btrfs_super_total_bytes(root->fs_info->super_copy); group_align = 64 * root->sectorsize; cur_start = 0; while (cur_start < total_bytes) { group_size = total_bytes / 12; group_size = min_t(u64, group_size, total_bytes - cur_start); if (cur_start == 0) { bit = BLOCK_GROUP_SYSTEM; group_type = BTRFS_BLOCK_GROUP_SYSTEM; group_size /= 4; group_size &= ~(group_align - 1); group_size = max_t(u64, group_size, 8 * 1024 * 1024); group_size = min_t(u64, group_size, 32 * 1024 * 1024); } else { group_size &= ~(group_align - 1); if (total_data >= total_metadata * 2) { group_type = BTRFS_BLOCK_GROUP_METADATA; group_size = min_t(u64, group_size, 1ULL * 1024 * 1024 * 1024); total_metadata += group_size; } else { group_type = BTRFS_BLOCK_GROUP_DATA; group_size = min_t(u64, group_size, 5ULL * 1024 * 1024 * 1024); total_data += group_size; } if ((total_bytes - cur_start) * 4 < group_size * 5) group_size = total_bytes - cur_start; } cache = kzalloc(sizeof(*cache), GFP_NOFS); BUG_ON(!cache); cache->key.objectid = cur_start; cache->key.offset = group_size; btrfs_set_key_type(&cache->key, BTRFS_BLOCK_GROUP_ITEM_KEY); btrfs_set_block_group_used(&cache->item, 0); btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid); btrfs_set_block_group_flags(&cache->item, group_type); cache->flags = group_type; ret = update_space_info(root->fs_info, group_type, group_size, 0, &cache->space_info); BUG_ON(ret); set_avail_alloc_bits(extent_root->fs_info, group_type); set_extent_bits(block_group_cache, cur_start, cur_start + group_size - 1, bit | EXTENT_LOCKED, GFP_NOFS); set_state_private(block_group_cache, cur_start, (unsigned long)cache); cur_start += group_size; } /* then insert all the items */ cur_start = 0; while(cur_start < total_bytes) { cache = btrfs_lookup_block_group(root->fs_info, cur_start); BUG_ON(!cache); ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item, sizeof(cache->item)); BUG_ON(ret); finish_current_insert(trans, extent_root); ret = del_pending_extents(trans, extent_root); BUG_ON(ret); cur_start = cache->key.objectid + cache->key.offset; } return 0; } int btrfs_update_block_group(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 bytenr, u64 num_bytes, int alloc, int mark_free) { return update_block_group(trans, root, bytenr, num_bytes, alloc, mark_free); } /* * Fixup block accounting. The initial block accounting created by * make_block_groups isn't accuracy in this case. */ int btrfs_fix_block_accounting(struct btrfs_trans_handle *trans, struct btrfs_root *root) { int ret; int slot; u64 start = 0; u64 bytes_used = 0; struct btrfs_path path; struct btrfs_key key; struct extent_buffer *leaf; struct btrfs_block_group_cache *cache; struct btrfs_fs_info *fs_info = root->fs_info; root = root->fs_info->extent_root; while(extent_root_pending_ops(fs_info)) { ret = finish_current_insert(trans, root); if (ret) return ret; ret = del_pending_extents(trans, root); if (ret) return ret; } while(1) { cache = btrfs_lookup_first_block_group(fs_info, start); if (!cache) break; start = cache->key.objectid + cache->key.offset; btrfs_set_block_group_used(&cache->item, 0); cache->space_info->bytes_used = 0; set_extent_bits(&root->fs_info->block_group_cache, cache->key.objectid, cache->key.objectid + cache->key.offset -1, BLOCK_GROUP_DIRTY, GFP_NOFS); } btrfs_init_path(&path); key.offset = 0; key.objectid = 0; btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY); ret = btrfs_search_slot(trans, root->fs_info->extent_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)) { ret = btrfs_next_leaf(root, &path); if (ret < 0) return ret; if (ret > 0) break; leaf = path.nodes[0]; slot = path.slots[0]; } btrfs_item_key_to_cpu(leaf, &key, slot); if (key.type == BTRFS_EXTENT_ITEM_KEY) { bytes_used += key.offset; ret = btrfs_update_block_group(trans, root, key.objectid, key.offset, 1, 0); BUG_ON(ret); } else if (key.type == BTRFS_METADATA_ITEM_KEY) { bytes_used += root->leafsize; ret = btrfs_update_block_group(trans, root, key.objectid, root->leafsize, 1, 0); BUG_ON(ret); } path.slots[0]++; } btrfs_set_super_bytes_used(root->fs_info->super_copy, bytes_used); btrfs_release_path(&path); return 0; } /* * Record a file extent. Do all the required works, such as inserting * file extent item, inserting extent item and backref item into extent * tree and updating block accounting. */ int btrfs_record_file_extent(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 objectid, struct btrfs_inode_item *inode, u64 file_pos, u64 disk_bytenr, u64 num_bytes) { int ret; struct btrfs_fs_info *info = root->fs_info; struct btrfs_root *extent_root = info->extent_root; struct extent_buffer *leaf; struct btrfs_file_extent_item *fi; struct btrfs_key ins_key; struct btrfs_path path; struct btrfs_extent_item *ei; u64 nbytes; if (disk_bytenr == 0) { ret = btrfs_insert_file_extent(trans, root, objectid, file_pos, disk_bytenr, num_bytes, num_bytes); return ret; } btrfs_init_path(&path); ins_key.objectid = objectid; ins_key.offset = file_pos; btrfs_set_key_type(&ins_key, BTRFS_EXTENT_DATA_KEY); ret = btrfs_insert_empty_item(trans, root, &path, &ins_key, sizeof(*fi)); if (ret) goto fail; leaf = path.nodes[0]; fi = btrfs_item_ptr(leaf, path.slots[0], struct btrfs_file_extent_item); btrfs_set_file_extent_generation(leaf, fi, trans->transid); btrfs_set_file_extent_type(leaf, fi, BTRFS_FILE_EXTENT_REG); btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr); btrfs_set_file_extent_disk_num_bytes(leaf, fi, num_bytes); btrfs_set_file_extent_offset(leaf, fi, 0); btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes); btrfs_set_file_extent_ram_bytes(leaf, fi, num_bytes); btrfs_set_file_extent_compression(leaf, fi, 0); btrfs_set_file_extent_encryption(leaf, fi, 0); btrfs_set_file_extent_other_encoding(leaf, fi, 0); btrfs_mark_buffer_dirty(leaf); nbytes = btrfs_stack_inode_nbytes(inode) + num_bytes; btrfs_set_stack_inode_nbytes(inode, nbytes); btrfs_release_path(&path); ins_key.objectid = disk_bytenr; ins_key.offset = num_bytes; ins_key.type = BTRFS_EXTENT_ITEM_KEY; ret = btrfs_insert_empty_item(trans, extent_root, &path, &ins_key, sizeof(*ei)); if (ret == 0) { leaf = path.nodes[0]; ei = btrfs_item_ptr(leaf, path.slots[0], struct btrfs_extent_item); btrfs_set_extent_refs(leaf, ei, 0); btrfs_set_extent_generation(leaf, ei, 0); btrfs_set_extent_flags(leaf, ei, BTRFS_EXTENT_FLAG_DATA); btrfs_mark_buffer_dirty(leaf); ret = btrfs_update_block_group(trans, root, disk_bytenr, num_bytes, 1, 0); if (ret) goto fail; } else if (ret != -EEXIST) { goto fail; } btrfs_extent_post_op(trans, extent_root); ret = btrfs_inc_extent_ref(trans, root, disk_bytenr, num_bytes, 0, root->root_key.objectid, objectid, file_pos); if (ret) goto fail; ret = 0; fail: btrfs_release_path(&path); return ret; }