/* * 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 #include "kerncompat.h" #include "kernel-lib/radix-tree.h" #include "kernel-lib/rbtree.h" #include "kernel-shared/ctree.h" #include "kernel-shared/disk-io.h" #include "kernel-shared/print-tree.h" #include "kernel-shared/transaction.h" #include "crypto/crc32c.h" #include "kernel-shared/volumes.h" #include "kernel-shared/free-space-cache.h" #include "kernel-shared/free-space-tree.h" #include "common/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 __free_extent(struct btrfs_trans_handle *trans, u64 bytenr, u64 num_bytes, u64 parent, u64 root_objectid, u64 owner_objectid, u64 owner_offset, int refs_to_drop); static struct btrfs_block_group * btrfs_find_block_group(struct btrfs_root *root, struct btrfs_block_group *hint, u64 search_start, int data, int owner); static int remove_sb_from_cache(struct btrfs_root *root, struct btrfs_block_group *cache) { u64 bytenr; u64 *logical; int stripe_len; int i, nr, ret; struct btrfs_fs_info *fs_info = root->fs_info; struct extent_io_tree *free_space_cache; free_space_cache = &fs_info->free_space_cache; for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) { bytenr = btrfs_sb_offset(i); ret = btrfs_rmap_block(fs_info, cache->start, bytenr, &logical, &nr, &stripe_len); BUG_ON(ret); while (nr--) { clear_extent_dirty(free_space_cache, logical[nr], logical[nr] + stripe_len - 1); } kfree(logical); } return 0; } static int cache_block_group(struct btrfs_root *root, struct btrfs_block_group *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 = READA_FORWARD; last = max_t(u64, block_group->start, 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->start) { goto next; } if (key.objectid >= block_group->start + block_group->length) { 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); } if (key.type == BTRFS_METADATA_ITEM_KEY) last = key.objectid + root->fs_info->nodesize; else last = key.objectid + key.offset; } next: path->slots[0]++; } if (block_group->start + block_group->length > last) { hole_size = block_group->start + block_group->length - last; set_extent_dirty(free_space_cache, last, last + hole_size - 1); } remove_sb_from_cache(root, block_group); block_group->cached = 1; err: btrfs_free_path(path); return 0; } /* * This adds the block group to the fs_info rb tree for the block group cache */ static int btrfs_add_block_group_cache(struct btrfs_fs_info *info, struct btrfs_block_group *block_group) { struct rb_node **p; struct rb_node *parent = NULL; struct btrfs_block_group *cache; ASSERT(block_group->length != 0); p = &info->block_group_cache_tree.rb_node; while (*p) { parent = *p; cache = rb_entry(parent, struct btrfs_block_group, cache_node); if (block_group->start < cache->start) p = &(*p)->rb_left; else if (block_group->start > cache->start) p = &(*p)->rb_right; else return -EEXIST; } rb_link_node(&block_group->cache_node, parent, p); rb_insert_color(&block_group->cache_node, &info->block_group_cache_tree); return 0; } /* * This will return the block group which contains @bytenr if it exists. * If found nothing, the return depends on @next. * * @next: * if 0, return NULL if there's no block group containing the bytenr. * if 1, return the block group which starts after @bytenr. */ static struct btrfs_block_group *block_group_cache_tree_search( struct btrfs_fs_info *info, u64 bytenr, int next) { struct btrfs_block_group *cache, *ret = NULL; struct rb_node *n; u64 end, start; n = info->block_group_cache_tree.rb_node; while (n) { cache = rb_entry(n, struct btrfs_block_group, cache_node); end = cache->start + cache->length - 1; start = cache->start; if (bytenr < start) { if (next && (!ret || start < ret->start)) ret = cache; n = n->rb_left; } else if (bytenr > start) { if (bytenr <= end) { ret = cache; break; } n = n->rb_right; } else { ret = cache; break; } } return ret; } /* * Return the block group that contains @bytenr, otherwise return the next one * that starts after @bytenr */ struct btrfs_block_group *btrfs_lookup_first_block_group( struct btrfs_fs_info *info, u64 bytenr) { return block_group_cache_tree_search(info, bytenr, 1); } /* * Return the block group that contains the given bytenr */ struct btrfs_block_group *btrfs_lookup_block_group( struct btrfs_fs_info *info, u64 bytenr) { return block_group_cache_tree_search(info, bytenr, 0); } static int block_group_bits(struct btrfs_block_group *cache, u64 bits) { return (cache->flags & bits) == bits; } static int noinline find_search_start(struct btrfs_root *root, struct btrfs_block_group **cache_ret, u64 *start_ret, int num, int data) { int ret; struct btrfs_block_group *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->start); 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->start + cache->length) { 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); return -ENOENT; } return -ENOSPC; new_group: last = cache->start + cache->length; 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 struct btrfs_block_group * btrfs_find_block_group(struct btrfs_root *root, struct btrfs_block_group *hint, u64 search_start, int data, int owner) { struct btrfs_block_group *cache; struct btrfs_block_group *found_group = NULL; struct btrfs_fs_info *info = root->fs_info; u64 used; u64 last = 0; u64 hint_last; u64 free_check; int full_search = 0; int factor = 10; if (!owner) factor = 10; if (search_start) { struct btrfs_block_group *shint; shint = btrfs_lookup_block_group(info, search_start); if (shint && !shint->ro && block_group_bits(shint, data)) { used = shint->used; if (used + shint->pinned < div_factor(shint->length, factor)) { return shint; } } } if (hint && !hint->ro && block_group_bits(hint, data)) { used = hint->used; if (used + hint->pinned < div_factor(hint->length, factor)) { return hint; } last = hint->start + hint->length; hint_last = last; } else { if (hint) hint_last = max(hint->start , search_start); else hint_last = search_start; last = hint_last; } again: while(1) { cache = btrfs_lookup_first_block_group(info, last); if (!cache) break; last = cache->start + cache->length; used = cache->used; if (!cache->ro && block_group_bits(cache, data)) { if (full_search) free_check = cache->length; else free_check = div_factor(cache->length, 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. */ 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; 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); } 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); btrfs_mark_buffer_dirty(leaf); } return ret; } static noinline u32 extent_data_ref_count(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); } 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; 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, 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) { 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]); 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(leaf); return -EINVAL; } 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_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(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(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(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; 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); /* 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); BUG_ON(err); return err; } int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info, 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(fs_info, SKINNY_METADATA)) { offset = fs_info->nodesize; metadata = 0; } path = btrfs_alloc_path(); if (!path) return -ENOMEM; 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, 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 == fs_info->nodesize) ret = 0; } if (ret) { btrfs_release_path(path); key.type = BTRFS_EXTENT_ITEM_KEY; key.offset = fs_info->nodesize; 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 { BUG(); } 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, u64 bytenr, int level, u64 flags) { struct btrfs_fs_info *fs_info = trans->fs_info; 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(fs_info, SKINNY_METADATA); path = btrfs_alloc_path(); if (!path) return -ENOMEM; key.objectid = bytenr; if (skinny_metadata) { key.offset = level; key.type = BTRFS_METADATA_ITEM_KEY; } else { key.offset = fs_info->nodesize; key.type = BTRFS_EXTENT_ITEM_KEY; } again: ret = btrfs_search_slot(trans, 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 == fs_info->nodesize && key.type == BTRFS_EXTENT_ITEM_KEY) ret = 0; } if (ret) { btrfs_release_path(path); key.offset = fs_info->nodesize; key.type = BTRFS_EXTENT_ITEM_KEY; goto again; } } if (ret != 0) { btrfs_print_leaf(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]); if (item_size < sizeof(*item)) { error( "unsupported or corrupted extent item, item size=%u expect minimal size=%zu", item_size, sizeof(*item)); ret = -EUCLEAN; goto out; } 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); 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 (key.type != 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 = root->fs_info->nodesize; 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 update_block_group_item(struct btrfs_trans_handle *trans, struct btrfs_path *path, struct btrfs_block_group *cache) { int ret; struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_root *root = fs_info->extent_root; unsigned long bi; struct btrfs_block_group_item bgi; struct extent_buffer *leaf; struct btrfs_key key; key.objectid = cache->start; key.type = BTRFS_BLOCK_GROUP_ITEM_KEY; key.offset = cache->length; ret = btrfs_search_slot(trans, root, &key, path, 0, 1); if (ret > 0) ret = -ENOENT; if (ret < 0) goto fail; leaf = path->nodes[0]; bi = btrfs_item_ptr_offset(leaf, path->slots[0]); btrfs_set_stack_block_group_used(&bgi, cache->used); btrfs_set_stack_block_group_flags(&bgi, cache->flags); btrfs_set_stack_block_group_chunk_objectid(&bgi, BTRFS_FIRST_CHUNK_TREE_OBJECTID); write_extent_buffer(leaf, &bgi, bi, sizeof(bgi)); btrfs_mark_buffer_dirty(leaf); fail: btrfs_release_path(path); return ret; } int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans) { struct btrfs_block_group *cache; struct btrfs_path *path; int ret = 0; path = btrfs_alloc_path(); if (!path) return -ENOMEM; while (!list_empty(&trans->dirty_bgs)) { cache = list_first_entry(&trans->dirty_bgs, struct btrfs_block_group, dirty_list); list_del_init(&cache->dirty_list); ret = update_block_group_item(trans, path, cache); if (ret) break; } btrfs_free_path(path); return ret; } 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 free_space_info(struct btrfs_fs_info *fs_info, u64 flags, u64 total_bytes, u64 bytes_used, struct btrfs_space_info **space_info) { struct btrfs_space_info *found; /* only support free block group which is empty */ if (bytes_used) return -ENOTEMPTY; found = __find_space_info(fs_info, flags); if (!found) return -ENOENT; if (found->total_bytes < total_bytes) { fprintf(stderr, "WARNING: bad space info to free %llu only have %llu\n", total_bytes, found->total_bytes); return -EINVAL; } found->total_bytes -= total_bytes; if (space_info) *space_info = found; return 0; } 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->bytes_reserved = 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_RAID1C3 | BTRFS_BLOCK_GROUP_RAID1C4 | 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_fs_info *fs_info, 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(fs_info, flags); if (!space_info) { ret = update_space_info(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 + space_info->bytes_reserved + alloc_bytes) < thresh) return 0; /* * Avoid allocating given chunk type */ if (fs_info->avoid_meta_chunk_alloc && (flags & BTRFS_BLOCK_GROUP_METADATA)) return 0; if (fs_info->avoid_sys_chunk_alloc && (flags & BTRFS_BLOCK_GROUP_SYSTEM)) return 0; /* * We're going to allocate new chunk, during the process, we will * allocate new tree blocks, which can trigger new chunk allocation * again. Avoid the recursion. */ if (trans->allocating_chunk) return 0; trans->allocating_chunk = 1; /* * The space_info only has block group type (data/meta/sys), doesn't * have the proper profile. * While we still want to handle mixed block groups properly. * So here add the extra bits for mixed profile. */ flags |= space_info->flags; ret = btrfs_alloc_chunk(trans, fs_info, &start, &num_bytes, flags); if (ret == -ENOSPC) { space_info->full = 1; trans->allocating_chunk = 0; return 0; } BUG_ON(ret); ret = btrfs_make_block_group(trans, fs_info, 0, flags, start, num_bytes); BUG_ON(ret); trans->allocating_chunk = 0; return 0; } static int update_block_group(struct btrfs_trans_handle *trans, u64 bytenr, u64 num_bytes, int alloc, int mark_free) { struct btrfs_fs_info *info = trans->fs_info; struct btrfs_block_group *cache; u64 total = num_bytes; u64 old_val; u64 byte_in_group; /* 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); while(total) { cache = btrfs_lookup_block_group(info, bytenr); if (!cache) { return -1; } byte_in_group = bytenr - cache->start; WARN_ON(byte_in_group > cache->length); if (list_empty(&cache->dirty_list)) list_add_tail(&cache->dirty_list, &trans->dirty_bgs); old_val = cache->used; num_bytes = min(total, cache->length- 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); } } cache->used = old_val; total -= num_bytes; bytenr += num_bytes; } return 0; } static int update_pinned_extents(struct btrfs_fs_info *fs_info, u64 bytenr, u64 num, int pin) { u64 len; struct btrfs_block_group *cache; if (pin) { set_extent_dirty(&fs_info->pinned_extents, bytenr, bytenr + num - 1); } else { clear_extent_dirty(&fs_info->pinned_extents, bytenr, bytenr + num - 1); } while (num > 0) { cache = btrfs_lookup_block_group(fs_info, bytenr); if (!cache) { len = min((u64)fs_info->sectorsize, num); goto next; } WARN_ON(!cache); len = min(num, cache->length - (bytenr - cache->start)); 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; } void btrfs_finish_extent_commit(struct btrfs_trans_handle *trans) { u64 start; u64 end; int ret; struct btrfs_fs_info *fs_info = trans->fs_info; struct extent_io_tree *free_space_cache = &fs_info->free_space_cache; struct extent_io_tree *pinned_extents = &fs_info->pinned_extents; while(1) { ret = find_first_extent_bit(pinned_extents, 0, &start, &end, EXTENT_DIRTY); if (ret) break; update_pinned_extents(trans->fs_info, start, end + 1 - start, 0); clear_extent_dirty(pinned_extents, start, end); set_extent_dirty(free_space_cache, start, end); } } static int pin_down_bytes(struct btrfs_trans_handle *trans, 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(trans->fs_info, 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(buf); free_extent_buffer(buf); return 1; } } free_extent_buffer(buf); pinit: update_pinned_extents(trans->fs_info, 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, bytenr, num_bytes, 1); } void btrfs_unpin_extent(struct btrfs_fs_info *fs_info, u64 bytenr, u64 num_bytes) { update_pinned_extents(fs_info, bytenr, num_bytes, 0); } /* * remove an extent from the root, returns 0 on success */ static int __free_extent(struct btrfs_trans_handle *trans, 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_root *extent_root = trans->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, SKINNY_METADATA); if (trans->fs_info->free_extent_hook) { trans->fs_info->free_extent_hook(bytenr, num_bytes, parent, root_objectid, owner_objectid, owner_offset, refs_to_drop); } path = btrfs_alloc_path(); if (!path) return -ENOMEM; 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--; } 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(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); printf("path->slots[0]: %d path->nodes[0]:\n", path->slots[0]); btrfs_print_leaf(path->nodes[0]); ret = -EIO; goto fail; } leaf = path->nodes[0]; item_size = btrfs_item_size_nr(leaf, extent_slot); if (item_size < sizeof(*ei)) { error( "unsupported or corrupted extent item, item size=%u expect minimal size=%zu", item_size, sizeof(*ei)); ret = -EUCLEAN; goto fail; } 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; if (found_extent) { BUG_ON(is_data && refs_to_drop != extent_data_ref_count(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; } } ret = pin_down_bytes(trans, 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, bytenr, num_bytes); BUG_ON(ret); } ret = add_to_free_space_tree(trans, bytenr, num_bytes); if (ret) { goto fail; } update_block_group(trans, bytenr, num_bytes, 0, mark_free); } fail: btrfs_free_path(path); return ret; } int btrfs_free_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct extent_buffer *buf, u64 parent, int last_ref) { return btrfs_free_extent(trans, root, buf->start, buf->len, parent, root->root_key.objectid, btrfs_header_level(buf), 0); } /* * 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) { int ret; WARN_ON(num_bytes < root->fs_info->sectorsize); /* * tree log blocks never actually go into the extent allocation * tree, just update pinning info and exit early. */ if (root_objectid == BTRFS_TREE_LOG_OBJECTID) { printf("PINNING EXTENTS IN LOG TREE\n"); WARN_ON(owner >= BTRFS_FIRST_FREE_OBJECTID); btrfs_pin_extent(trans->fs_info, bytenr, num_bytes); ret = 0; } else if (owner < BTRFS_FIRST_FREE_OBJECTID) { BUG_ON(offset); ret = btrfs_add_delayed_tree_ref(trans->fs_info, trans, bytenr, num_bytes, parent, root_objectid, (int)owner, BTRFS_DROP_DELAYED_REF, NULL, NULL, NULL); } else { ret = __free_extent(trans, bytenr, num_bytes, parent, root_objectid, owner, offset, 1); } return ret; } static u64 stripe_align(struct btrfs_root *root, u64 val) { return round_up(val, (u64)root->fs_info->stripesize); } /* * 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 *block_group; int full_scan = 0; int wrapped = 0; WARN_ON(num_bytes < info->sectorsize); ins->type = 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->start + block_group->length) { search_start = block_group->start + block_group->length; 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 (info->excluded_extents && test_range_bit(info->excluded_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)) { if (check_crossing_stripes(info, ins->objectid, num_bytes)) { struct btrfs_block_group *bg_cache; u64 bg_offset; bg_cache = btrfs_lookup_block_group(info, ins->objectid); if (!bg_cache) goto no_bg_cache; bg_offset = ins->objectid - bg_cache->start; search_start = round_up( bg_offset + num_bytes, BTRFS_STRIPE_LEN) + bg_cache->start; goto new_group; } no_bg_cache: 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, bool is_data) { int ret; u64 search_start = 0; u64 alloc_profile; u64 profile; struct btrfs_fs_info *info = root->fs_info; if (is_data) { alloc_profile = info->avail_data_alloc_bits & info->data_alloc_profile; profile = BTRFS_BLOCK_GROUP_DATA | alloc_profile; } else if (info->system_allocs == 1 || root == info->chunk_root) { alloc_profile = info->avail_system_alloc_bits & info->system_alloc_profile; profile = BTRFS_BLOCK_GROUP_SYSTEM | alloc_profile; } else { alloc_profile = info->avail_metadata_alloc_bits & info->metadata_alloc_profile; profile = BTRFS_BLOCK_GROUP_METADATA | alloc_profile; } /* * Also preallocate metadata for csum tree and fs trees (root->ref_cows * already set), as they can consume a lot of metadata space. * Pre-allocate to avoid unexpected ENOSPC. */ if (root->ref_cows || root->root_key.objectid == BTRFS_CSUM_TREE_OBJECTID) { if (!(profile & BTRFS_BLOCK_GROUP_METADATA)) { ret = do_chunk_alloc(trans, info, num_bytes, BTRFS_BLOCK_GROUP_METADATA); BUG_ON(ret); } ret = do_chunk_alloc(trans, info, num_bytes + SZ_2M, profile); BUG_ON(ret); } WARN_ON(num_bytes < info->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, profile); if (ret < 0) return ret; clear_extent_dirty(&info->free_space_cache, ins->objectid, ins->objectid + ins->offset - 1); return ret; } static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans, struct btrfs_delayed_ref_node *node, struct btrfs_delayed_extent_op *extent_op) { struct btrfs_delayed_tree_ref *ref = btrfs_delayed_node_to_tree_ref(node); bool skinny_metadata = btrfs_fs_incompat(trans->fs_info, SKINNY_METADATA); struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_extent_item *extent_item; struct btrfs_extent_inline_ref *iref; struct btrfs_space_info *sinfo; struct extent_buffer *leaf; struct btrfs_path *path; struct btrfs_key ins; u32 size = sizeof(*extent_item) + sizeof(*iref); u64 start, end; int ret; sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA); ASSERT(sinfo); ins.objectid = node->bytenr; if (skinny_metadata) { ins.offset = ref->level; ins.type = BTRFS_METADATA_ITEM_KEY; } else { ins.offset = node->num_bytes; ins.type = BTRFS_EXTENT_ITEM_KEY; size += sizeof(struct btrfs_tree_block_info); } if (ref->root == BTRFS_EXTENT_TREE_OBJECTID) { ret = find_first_extent_bit(&trans->fs_info->extent_ins, node->bytenr, &start, &end, EXTENT_LOCKED); ASSERT(!ret); ASSERT(start == node->bytenr); ASSERT(end == node->bytenr + node->num_bytes - 1); } path = btrfs_alloc_path(); if (!path) return -ENOMEM; ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path, &ins, size); if (ret) return 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, trans->transid); btrfs_set_extent_flags(leaf, extent_item, extent_op->flags_to_set | BTRFS_EXTENT_FLAG_TREE_BLOCK); if (skinny_metadata) { iref = (struct btrfs_extent_inline_ref *)(extent_item + 1); } else { struct btrfs_tree_block_info *block_info; block_info = (struct btrfs_tree_block_info *)(extent_item + 1); btrfs_set_tree_block_key(leaf, block_info, &extent_op->key); btrfs_set_tree_block_level(leaf, block_info, ref->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, ref->root); btrfs_mark_buffer_dirty(leaf); btrfs_free_path(path); ret = remove_from_free_space_tree(trans, ins.objectid, fs_info->nodesize); if (ret) return ret; ret = update_block_group(trans, ins.objectid, fs_info->nodesize, 1, 0); if (sinfo) { if (fs_info->nodesize > sinfo->bytes_reserved) { WARN_ON(1); sinfo->bytes_reserved = 0; } else { sinfo->bytes_reserved -= fs_info->nodesize; } } if (ref->root == BTRFS_EXTENT_TREE_OBJECTID) { clear_extent_bits(&trans->fs_info->extent_ins, start, end, EXTENT_LOCKED); } 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; u64 extent_size; struct btrfs_delayed_extent_op *extent_op; struct btrfs_space_info *sinfo; struct btrfs_fs_info *fs_info = root->fs_info; bool skinny_metadata = btrfs_fs_incompat(root->fs_info, SKINNY_METADATA); extent_op = btrfs_alloc_delayed_extent_op(); if (!extent_op) return -ENOMEM; sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA); if (!sinfo) { error("Corrupted fs, no valid METADATA block group found"); return -EUCLEAN; } ret = btrfs_reserve_extent(trans, root, num_bytes, empty_size, hint_byte, search_end, ins, 0); if (ret < 0) return ret; if (key) memcpy(&extent_op->key, key, sizeof(extent_op->key)); else memset(&extent_op->key, 0, sizeof(extent_op->key)); extent_op->flags_to_set = flags; extent_op->update_key = skinny_metadata ? false : true; extent_op->update_flags = true; extent_op->is_data = false; extent_op->level = level; extent_size = ins->offset; if (btrfs_fs_incompat(root->fs_info, SKINNY_METADATA)) { ins->offset = level; ins->type = BTRFS_METADATA_ITEM_KEY; } /* Ensure this reserved extent is not found by the allocator */ if (root_objectid == BTRFS_EXTENT_TREE_OBJECTID) { ret = set_extent_bits(&trans->fs_info->extent_ins, ins->objectid, ins->objectid + extent_size - 1, EXTENT_LOCKED); BUG_ON(ret); } sinfo->bytes_reserved += extent_size; ret = btrfs_add_delayed_tree_ref(root->fs_info, trans, ins->objectid, extent_size, 0, root_objectid, level, BTRFS_ADD_DELAYED_EXTENT, extent_op, NULL, NULL); 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->fs_info, ins.objectid); 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; } int btrfs_free_block_groups(struct btrfs_fs_info *info) { struct btrfs_space_info *sinfo; struct btrfs_block_group *cache, *next; u64 start; u64 end; int ret; rbtree_postorder_for_each_entry_safe(cache, next, &info->block_group_cache_tree, cache_node) { if (!list_empty(&cache->dirty_list)) list_del_init(&cache->dirty_list); RB_CLEAR_NODE(&cache->cache_node); if (cache->free_space_ctl) { btrfs_remove_free_space_cache(cache); kfree(cache->free_space_ctl); } kfree(cache); } 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); } while (!list_empty(&info->space_info)) { sinfo = list_entry(info->space_info.next, struct btrfs_space_info, list); list_del_init(&sinfo->list); if (sinfo->bytes_reserved) warning( "reserved space leaked, flag=0x%llx bytes_reserved=%llu", sinfo->flags, sinfo->bytes_reserved); kfree(sinfo); } return 0; } /* * Find a block group which starts >= @key->objectid in extent tree. * * Return 0 for found * Return >0 for not found * Return <0 for error */ 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 = 1; error: return ret; } static int read_block_group_item(struct btrfs_block_group *cache, struct btrfs_path *path, const struct btrfs_key *key) { struct extent_buffer *leaf = path->nodes[0]; struct btrfs_block_group_item bgi; int slot = path->slots[0]; ASSERT(key->type == BTRFS_BLOCK_GROUP_ITEM_KEY); cache->start = key->objectid; cache->length = key->offset; read_extent_buffer(leaf, &bgi, btrfs_item_ptr_offset(leaf, slot), sizeof(bgi)); cache->used = btrfs_stack_block_group_used(&bgi); cache->flags = btrfs_stack_block_group_flags(&bgi); return 0; } /* * Read out one BLOCK_GROUP_ITEM and insert it into block group cache. * * Return 0 if nothing wrong (either insert the bg cache or skip 0 sized bg) * Return <0 for error. */ static int read_one_block_group(struct btrfs_fs_info *fs_info, struct btrfs_path *path) { struct extent_buffer *leaf = path->nodes[0]; struct btrfs_space_info *space_info; struct btrfs_block_group *cache; struct btrfs_key key; int slot = path->slots[0]; int ret; btrfs_item_key_to_cpu(leaf, &key, slot); ASSERT(key.type == BTRFS_BLOCK_GROUP_ITEM_KEY); /* * Skip 0 sized block group, don't insert them into block group cache * tree, as its length is 0, it won't get freed at close_ctree() time. */ if (key.offset == 0) return 0; cache = kzalloc(sizeof(*cache), GFP_NOFS); if (!cache) return -ENOMEM; ret = read_block_group_item(cache, path, &key); if (ret < 0) { free(cache); return ret; } INIT_LIST_HEAD(&cache->dirty_list); set_avail_alloc_bits(fs_info, cache->flags); ret = btrfs_chunk_readonly(fs_info, cache->start); if (ret < 0) { free(cache); return ret; } if (ret) cache->ro = 1; exclude_super_stripes(fs_info, cache); ret = update_space_info(fs_info, cache->flags, cache->length, cache->used, &space_info); if (ret < 0) { free(cache); return ret; } cache->space_info = space_info; btrfs_add_block_group_cache(fs_info, cache); return 0; } int btrfs_read_block_groups(struct btrfs_fs_info *fs_info) { struct btrfs_path path; struct btrfs_root *root; int ret; struct btrfs_key key; root = fs_info->extent_root; key.objectid = 0; key.offset = 0; key.type = BTRFS_BLOCK_GROUP_ITEM_KEY; btrfs_init_path(&path); while(1) { ret = find_first_block_group(root, &path, &key); if (ret > 0) { ret = 0; goto error; } if (ret != 0) { goto error; } btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]); ret = read_one_block_group(fs_info, &path); if (ret < 0 && ret != -ENOENT) goto error; if (key.offset == 0) key.objectid++; else key.objectid = key.objectid + key.offset; key.offset = 0; btrfs_release_path(&path); } ret = 0; error: btrfs_release_path(&path); return ret; } struct btrfs_block_group * btrfs_add_block_group(struct btrfs_fs_info *fs_info, u64 bytes_used, u64 type, u64 chunk_offset, u64 size) { int ret; struct btrfs_block_group *cache; cache = kzalloc(sizeof(*cache), GFP_NOFS); BUG_ON(!cache); cache->start = chunk_offset; cache->length = size; cache->used = bytes_used; cache->flags = type; INIT_LIST_HEAD(&cache->dirty_list); exclude_super_stripes(fs_info, cache); ret = update_space_info(fs_info, cache->flags, size, bytes_used, &cache->space_info); BUG_ON(ret); ret = btrfs_add_block_group_cache(fs_info, 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_fs_info *fs_info, u64 bytes_used, u64 type, u64 chunk_offset, u64 size) { int ret; struct btrfs_root *extent_root = fs_info->extent_root; struct btrfs_block_group *cache; struct btrfs_block_group_item bgi; struct btrfs_key key; cache = btrfs_add_block_group(fs_info, bytes_used, type, chunk_offset, size); btrfs_set_stack_block_group_used(&bgi, cache->used); btrfs_set_stack_block_group_flags(&bgi, cache->flags); btrfs_set_stack_block_group_chunk_objectid(&bgi, BTRFS_FIRST_CHUNK_TREE_OBJECTID); key.objectid = cache->start; key.type = BTRFS_BLOCK_GROUP_ITEM_KEY; key.offset = cache->length; ret = btrfs_insert_item(trans, extent_root, &key, &bgi, sizeof(bgi)); BUG_ON(ret); return 0; } static int insert_block_group_item(struct btrfs_trans_handle *trans, struct btrfs_block_group *block_group) { struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_block_group_item bgi; struct btrfs_root *root; struct btrfs_key key; btrfs_set_stack_block_group_used(&bgi, block_group->used); btrfs_set_stack_block_group_chunk_objectid(&bgi, BTRFS_FIRST_CHUNK_TREE_OBJECTID); btrfs_set_stack_block_group_flags(&bgi, block_group->flags); key.objectid = block_group->start; key.type = BTRFS_BLOCK_GROUP_ITEM_KEY; key.offset = block_group->length; root = fs_info->extent_root; return btrfs_insert_item(trans, root, &key, &bgi, sizeof(bgi)); } /* * 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_fs_info *fs_info) { u64 total_bytes; u64 cur_start; u64 group_type; u64 group_size; u64 group_align; u64 total_data = 0; u64 total_metadata = 0; int ret; struct btrfs_block_group *cache; total_bytes = btrfs_super_total_bytes(fs_info->super_copy); group_align = 64 * fs_info->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) { group_type = BTRFS_BLOCK_GROUP_SYSTEM; group_size /= 4; group_size &= ~(group_align - 1); group_size = max_t(u64, group_size, SZ_8M); group_size = min_t(u64, group_size, SZ_32M); } 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, SZ_1G); total_metadata += group_size; } else { group_type = BTRFS_BLOCK_GROUP_DATA; group_size = min_t(u64, group_size, 5ULL * SZ_1G); 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->start = cur_start; cache->length = group_size; cache->used = 0; cache->flags = group_type; INIT_LIST_HEAD(&cache->dirty_list); ret = update_space_info(fs_info, group_type, group_size, 0, &cache->space_info); BUG_ON(ret); set_avail_alloc_bits(fs_info, group_type); btrfs_add_block_group_cache(fs_info, cache); cur_start += group_size; } /* then insert all the items */ cur_start = 0; while(cur_start < total_bytes) { cache = btrfs_lookup_block_group(fs_info, cur_start); BUG_ON(!cache); ret = insert_block_group_item(trans, cache); BUG_ON(ret); cur_start = cache->start + cache->length; } return 0; } int btrfs_update_block_group(struct btrfs_trans_handle *trans, u64 bytenr, u64 num_bytes, int alloc, int mark_free) { return update_block_group(trans, bytenr, num_bytes, alloc, mark_free); } /* * Just remove a block group item in extent tree * Caller should ensure the block group is empty and all space is pinned. * Or new tree block/data may be allocated into it. */ static int remove_block_group_item(struct btrfs_trans_handle *trans, struct btrfs_path *path, struct btrfs_block_group *block_group) { struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_key key; struct btrfs_root *root = fs_info->extent_root; int ret = 0; key.objectid = block_group->start; key.offset = block_group->length; key.type = BTRFS_BLOCK_GROUP_ITEM_KEY; ret = btrfs_search_slot(trans, root, &key, path, -1, 1); if (ret > 0) ret = -ENOENT; if (ret < 0) return ret; return btrfs_del_item(trans, root, path); } static int free_dev_extent_item(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info, u64 devid, u64 dev_offset) { struct btrfs_root *root = fs_info->dev_root; struct btrfs_path *path; struct btrfs_key key; int ret; path = btrfs_alloc_path(); if (!path) return -ENOMEM; key.objectid = devid; key.type = BTRFS_DEV_EXTENT_KEY; key.offset = dev_offset; ret = btrfs_search_slot(trans, root, &key, path, -1, 1); if (ret < 0) goto out; if (ret > 0) { ret = -ENOENT; goto out; } ret = btrfs_del_item(trans, root, path); out: btrfs_free_path(path); return ret; } static int free_chunk_dev_extent_items(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info, u64 chunk_offset) { struct btrfs_chunk *chunk = NULL; struct btrfs_root *root= fs_info->chunk_root; struct btrfs_path *path; struct btrfs_key key; u16 num_stripes; int i; int ret; path = btrfs_alloc_path(); if (!path) return -ENOMEM; key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; key.type = BTRFS_CHUNK_ITEM_KEY; key.offset = chunk_offset; ret = btrfs_search_slot(trans, root, &key, path, 0, 0); if (ret < 0) goto out; if (ret > 0) { ret = -ENOENT; goto out; } chunk = btrfs_item_ptr(path->nodes[0], path->slots[0], struct btrfs_chunk); num_stripes = btrfs_chunk_num_stripes(path->nodes[0], chunk); for (i = 0; i < num_stripes; i++) { ret = free_dev_extent_item(trans, fs_info, btrfs_stripe_devid_nr(path->nodes[0], chunk, i), btrfs_stripe_offset_nr(path->nodes[0], chunk, i)); if (ret < 0) goto out; } out: btrfs_free_path(path); return ret; } static int free_system_chunk_item(struct btrfs_super_block *super, struct btrfs_key *key) { struct btrfs_disk_key *disk_key; struct btrfs_key cpu_key; u32 array_size = btrfs_super_sys_array_size(super); char *ptr = (char *)super->sys_chunk_array; int cur = 0; int ret = -ENOENT; while (cur < btrfs_super_sys_array_size(super)) { struct btrfs_chunk *chunk; u32 num_stripes; u32 chunk_len; disk_key = (struct btrfs_disk_key *)(ptr + cur); btrfs_disk_key_to_cpu(&cpu_key, disk_key); if (cpu_key.type != BTRFS_CHUNK_ITEM_KEY) { /* just in case */ ret = -EIO; goto out; } chunk = (struct btrfs_chunk *)(ptr + cur + sizeof(*disk_key)); num_stripes = btrfs_stack_chunk_num_stripes(chunk); chunk_len = btrfs_chunk_item_size(num_stripes) + sizeof(*disk_key); if (key->objectid == cpu_key.objectid && key->offset == cpu_key.offset && key->type == cpu_key.type) { memmove(ptr + cur, ptr + cur + chunk_len, array_size - cur - chunk_len); array_size -= chunk_len; btrfs_set_super_sys_array_size(super, array_size); ret = 0; goto out; } cur += chunk_len; } out: return ret; } static int free_chunk_item(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info, u64 bytenr) { struct btrfs_path *path; struct btrfs_key key; struct btrfs_root *root = fs_info->chunk_root; struct btrfs_chunk *chunk; u64 chunk_type; int ret; key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; key.offset = bytenr; key.type = BTRFS_CHUNK_ITEM_KEY; path = btrfs_alloc_path(); if (!path) return -ENOMEM; ret = btrfs_search_slot(trans, root, &key, path, -1, 1); if (ret > 0) { ret = -ENOENT; goto out; } if (ret < 0) goto out; chunk = btrfs_item_ptr(path->nodes[0], path->slots[0], struct btrfs_chunk); chunk_type = btrfs_chunk_type(path->nodes[0], chunk); ret = btrfs_del_item(trans, root, path); if (ret < 0) goto out; if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) ret = free_system_chunk_item(fs_info->super_copy, &key); out: btrfs_free_path(path); return ret; } static u64 get_dev_extent_len(struct map_lookup *map) { int div; switch (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) { case 0: /* Single */ case BTRFS_BLOCK_GROUP_DUP: case BTRFS_BLOCK_GROUP_RAID1: case BTRFS_BLOCK_GROUP_RAID1C3: case BTRFS_BLOCK_GROUP_RAID1C4: div = 1; break; case BTRFS_BLOCK_GROUP_RAID5: div = (map->num_stripes - 1); break; case BTRFS_BLOCK_GROUP_RAID6: div = (map->num_stripes - 2); break; case BTRFS_BLOCK_GROUP_RAID10: div = (map->num_stripes / map->sub_stripes); break; default: /* normally, read chunk security hook should handled it */ BUG_ON(1); } return map->ce.size / div; } /* free block group/chunk related caches */ static int free_block_group_cache(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info, u64 bytenr, u64 len) { struct btrfs_block_group *cache; struct cache_extent *ce; struct map_lookup *map; int ret; int i; u64 flags; /* Free block group cache first */ cache = btrfs_lookup_block_group(fs_info, bytenr); if (!cache) return -ENOENT; flags = cache->flags; if (cache->free_space_ctl) { btrfs_remove_free_space_cache(cache); kfree(cache->free_space_ctl); } if (!list_empty(&cache->dirty_list)) list_del(&cache->dirty_list); rb_erase(&cache->cache_node, &fs_info->block_group_cache_tree); ret = free_space_info(fs_info, flags, len, 0, NULL); if (ret < 0) goto out; kfree(cache); /* Then free mapping info and dev usage info */ ce = search_cache_extent(&fs_info->mapping_tree.cache_tree, bytenr); if (!ce || ce->start != bytenr) { ret = -ENOENT; goto out; } map = container_of(ce, struct map_lookup, ce); for (i = 0; i < map->num_stripes; i++) { struct btrfs_device *device; device = map->stripes[i].dev; device->bytes_used -= get_dev_extent_len(map); ret = btrfs_update_device(trans, device); if (ret < 0) goto out; } remove_cache_extent(&fs_info->mapping_tree.cache_tree, ce); free(map); out: return ret; } int btrfs_remove_block_group(struct btrfs_trans_handle *trans, u64 bytenr, u64 len) { struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_block_group *block_group; struct btrfs_path path; int ret = 0; block_group = btrfs_lookup_block_group(fs_info, bytenr); if (!block_group || block_group->start != bytenr || block_group->length != len) return -ENOENT; /* Double check the block group to ensure it's empty */ if (block_group->used) { fprintf(stderr, "WARNING: block group [%llu,%llu) is not empty\n", bytenr, bytenr + len); return -EUCLEAN; } /* * Now pin all space in the block group, to prevent further transaction * allocate space from it. * Every operation needs a transaction must be in the range. */ btrfs_pin_extent(fs_info, bytenr, len); btrfs_init_path(&path); /* delete block group item and chunk item */ ret = remove_block_group_item(trans, &path, block_group); btrfs_release_path(&path); if (ret < 0) { fprintf(stderr, "failed to free block group item for [%llu,%llu)\n", bytenr, bytenr + len); btrfs_unpin_extent(fs_info, bytenr, len); return ret; } ret = free_chunk_dev_extent_items(trans, fs_info, bytenr); if (ret < 0) { fprintf(stderr, "failed to dev extents belongs to [%llu,%llu)\n", bytenr, bytenr + len); btrfs_unpin_extent(fs_info, bytenr, len); return ret; } ret = free_chunk_item(trans, fs_info, bytenr); if (ret < 0) { fprintf(stderr, "failed to free chunk for [%llu,%llu)\n", bytenr, bytenr + len); btrfs_unpin_extent(fs_info, bytenr, len); return ret; } /* Now release the block_group_cache */ ret = free_block_group_cache(trans, fs_info, bytenr, len); btrfs_unpin_extent(fs_info, bytenr, len); return ret; } /* * 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) { int ret = 0; 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; struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_root *root = fs_info->extent_root; ret = btrfs_run_delayed_refs(trans, -1); if (ret) return ret; while(1) { cache = btrfs_lookup_first_block_group(fs_info, start); if (!cache) break; start = cache->start + cache->length; cache->used = 0; cache->space_info->bytes_used = 0; if (list_empty(&cache->dirty_list)) list_add_tail(&cache->dirty_list, &trans->dirty_bgs); } btrfs_init_path(&path); key.offset = 0; key.objectid = 0; key.type = 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, key.objectid, key.offset, 1, 0); BUG_ON(ret); } else if (key.type == BTRFS_METADATA_ITEM_KEY) { bytes_used += fs_info->nodesize; ret = btrfs_update_block_group(trans, key.objectid, fs_info->nodesize, 1, 0); if (ret) goto out; } path.slots[0]++; } btrfs_set_super_bytes_used(root->fs_info->super_copy, bytes_used); ret = 0; out: btrfs_release_path(&path); return ret; } static void __get_extent_size(struct btrfs_root *root, struct btrfs_path *path, u64 *start, u64 *len) { struct btrfs_key key; btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); BUG_ON(!(key.type == BTRFS_EXTENT_ITEM_KEY || key.type == BTRFS_METADATA_ITEM_KEY)); *start = key.objectid; if (key.type == BTRFS_EXTENT_ITEM_KEY) *len = key.offset; else *len = root->fs_info->nodesize; } /* * Find first overlap extent for range [bytenr, bytenr + len) * Return 0 for found and point path to it. * Return >0 for not found. * Return <0 for err */ static int btrfs_search_overlap_extent(struct btrfs_root *root, struct btrfs_path *path, u64 bytenr, u64 len) { struct btrfs_key key; u64 cur_start; u64 cur_len; int ret; key.objectid = bytenr; key.type = BTRFS_EXTENT_DATA_KEY; key.offset = (u64)-1; ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); if (ret < 0) return ret; BUG_ON(ret == 0); ret = btrfs_previous_extent_item(root, path, 0); if (ret < 0) return ret; /* no previous, check next extent */ if (ret > 0) goto next; __get_extent_size(root, path, &cur_start, &cur_len); /* Tail overlap */ if (cur_start + cur_len > bytenr) return 1; next: ret = btrfs_next_extent_item(root, path, bytenr + len); if (ret < 0) return ret; /* No next, prev already checked, no overlap */ if (ret > 0) return 0; __get_extent_size(root, path, &cur_start, &cur_len); /* head overlap*/ if (cur_start < bytenr + len) return 1; return 0; } static 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 *ret_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; u64 extent_num_bytes; u64 extent_bytenr; u64 extent_offset; u64 num_bytes = *ret_num_bytes; /* * All supported file system should not use its 0 extent. * As it's for hole * * And hole extent has no size limit, no need to loop. */ if (disk_bytenr == 0) { ret = btrfs_insert_file_extent(trans, root, objectid, file_pos, disk_bytenr, num_bytes, num_bytes); return ret; } num_bytes = min_t(u64, num_bytes, BTRFS_MAX_EXTENT_SIZE); path = btrfs_alloc_path(); if (!path) return -ENOMEM; /* First to check extent overlap */ ret = btrfs_search_overlap_extent(extent_root, path, disk_bytenr, num_bytes); if (ret < 0) goto fail; if (ret > 0) { /* Found overlap */ u64 cur_start; u64 cur_len; __get_extent_size(extent_root, path, &cur_start, &cur_len); /* * For convert case, this extent should be a subset of * existing one. */ BUG_ON(disk_bytenr < cur_start); extent_bytenr = cur_start; extent_num_bytes = cur_len; extent_offset = disk_bytenr - extent_bytenr; } else { /* No overlap, create new extent */ 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, disk_bytenr, num_bytes, 1, 0); if (ret) goto fail; } else if (ret != -EEXIST) { goto fail; } btrfs_run_delayed_refs(trans, -1); extent_bytenr = disk_bytenr; extent_num_bytes = num_bytes; extent_offset = 0; } btrfs_release_path(path); ins_key.objectid = objectid; ins_key.offset = file_pos; ins_key.type = 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, extent_bytenr); btrfs_set_file_extent_disk_num_bytes(leaf, fi, extent_num_bytes); btrfs_set_file_extent_offset(leaf, fi, extent_offset); btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes); btrfs_set_file_extent_ram_bytes(leaf, fi, extent_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); ret = btrfs_inc_extent_ref(trans, root, extent_bytenr, extent_num_bytes, 0, root->root_key.objectid, objectid, file_pos - extent_offset); if (ret) goto fail; ret = 0; *ret_num_bytes = min(extent_num_bytes - extent_offset, num_bytes); fail: btrfs_free_path(path); return ret; } /* * 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) { u64 cur_disk_bytenr = disk_bytenr; u64 cur_file_pos = file_pos; u64 cur_num_bytes = num_bytes; int ret = 0; while (num_bytes > 0) { ret = __btrfs_record_file_extent(trans, root, objectid, inode, cur_file_pos, cur_disk_bytenr, &cur_num_bytes); if (ret < 0) break; cur_disk_bytenr += cur_num_bytes; cur_file_pos += cur_num_bytes; num_bytes -= cur_num_bytes; } return ret; } static int add_excluded_extent(struct btrfs_fs_info *fs_info, u64 start, u64 num_bytes) { u64 end = start + num_bytes - 1; set_extent_bits(&fs_info->pinned_extents, start, end, EXTENT_UPTODATE); return 0; } void free_excluded_extents(struct btrfs_fs_info *fs_info, struct btrfs_block_group *cache) { u64 start, end; start = cache->start; end = start + cache->length - 1; clear_extent_bits(&fs_info->pinned_extents, start, end, EXTENT_UPTODATE); } int exclude_super_stripes(struct btrfs_fs_info *fs_info, struct btrfs_block_group *cache) { u64 bytenr; u64 *logical; int stripe_len; int i, nr, ret; if (cache->start < BTRFS_SUPER_INFO_OFFSET) { stripe_len = BTRFS_SUPER_INFO_OFFSET - cache->start; cache->bytes_super += stripe_len; ret = add_excluded_extent(fs_info, cache->start, stripe_len); if (ret) return ret; } for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) { bytenr = btrfs_sb_offset(i); ret = btrfs_rmap_block(fs_info, cache->start, bytenr, &logical, &nr, &stripe_len); if (ret) return ret; while (nr--) { u64 start, len; if (logical[nr] >= cache->start + cache->length) continue; if (logical[nr] + stripe_len <= cache->start) continue; start = logical[nr]; if (start < cache->start) { start = cache->start; len = (logical[nr] + stripe_len) - start; } else { len = min_t(u64, stripe_len, cache->start + cache->length - start); } cache->bytes_super += len; ret = add_excluded_extent(fs_info, start, len); if (ret) { kfree(logical); return ret; } } kfree(logical); } return 0; } u64 add_new_free_space(struct btrfs_block_group *block_group, struct btrfs_fs_info *info, u64 start, u64 end) { u64 extent_start, extent_end, size, total_added = 0; int ret; while (start < end) { ret = find_first_extent_bit(&info->pinned_extents, start, &extent_start, &extent_end, EXTENT_DIRTY | EXTENT_UPTODATE); if (ret) break; if (extent_start <= start) { start = extent_end + 1; } else if (extent_start > start && extent_start < end) { size = extent_start - start; total_added += size; ret = btrfs_add_free_space(block_group->free_space_ctl, start, size); BUG_ON(ret); /* -ENOMEM or logic error */ start = extent_end + 1; } else { break; } } if (start < end) { size = end - start; total_added += size; ret = btrfs_add_free_space(block_group->free_space_ctl, start, size); BUG_ON(ret); /* -ENOMEM or logic error */ } return total_added; } static void cleanup_extent_op(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info, struct btrfs_delayed_ref_head *head) { struct btrfs_delayed_extent_op *extent_op = head->extent_op; if (!extent_op) return; head->extent_op = NULL; btrfs_free_delayed_extent_op(extent_op); } static void unselect_delayed_ref_head(struct btrfs_delayed_ref_root *delayed_refs, struct btrfs_delayed_ref_head *head) { head->processing = 0; delayed_refs->num_heads_ready++; } int cleanup_ref_head(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info, struct btrfs_delayed_ref_head *head) { struct btrfs_delayed_ref_root *delayed_refs; delayed_refs = &trans->delayed_refs; cleanup_extent_op(trans, fs_info, head); /* * Need to drop our head ref lock and re-acquire the delayed ref lock * and then re-check to make sure nobody got added. */ if (!RB_EMPTY_ROOT(&head->ref_tree) || head->extent_op) return 1; delayed_refs->num_heads--; rb_erase(&head->href_node, &delayed_refs->href_root); RB_CLEAR_NODE(&head->href_node); if (head->must_insert_reserved) { btrfs_pin_extent(fs_info, head->bytenr, head->num_bytes); if (!head->is_data) { struct btrfs_space_info *sinfo; sinfo = __find_space_info(trans->fs_info, BTRFS_BLOCK_GROUP_METADATA); ASSERT(sinfo); sinfo->bytes_reserved -= head->num_bytes; } } btrfs_put_delayed_ref_head(head); return 0; } static inline struct btrfs_delayed_ref_node * select_delayed_ref(struct btrfs_delayed_ref_head *head) { struct btrfs_delayed_ref_node *ref; if (RB_EMPTY_ROOT(&head->ref_tree)) return NULL; /* * Select a delayed ref of type BTRFS_ADD_DELAYED_REF first. * This is to prevent a ref count from going down to zero, which deletes * the extent item from the extent tree, when there still are references * to add, which would fail because they would not find the extent item. */ if (!list_empty(&head->ref_add_list)) return list_first_entry(&head->ref_add_list, struct btrfs_delayed_ref_node, add_list); ref = rb_entry(rb_first(&head->ref_tree), struct btrfs_delayed_ref_node, ref_node); ASSERT(list_empty(&ref->add_list)); return ref; } static int run_delayed_tree_ref(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info, struct btrfs_delayed_ref_node *node, struct btrfs_delayed_extent_op *extent_op, int insert_reserved) { int ret = 0; struct btrfs_delayed_tree_ref *ref; u64 parent = 0; u64 ref_root = 0; ref = btrfs_delayed_node_to_tree_ref(node); if (node->type == BTRFS_SHARED_BLOCK_REF_KEY) parent = ref->parent; ref_root = ref->root; if (node->ref_mod != 1) { printf("btree block(%llu) has %d references rather than 1: action %u ref_root %llu parent %llu", node->bytenr, node->ref_mod, node->action, ref_root, parent); return -EIO; } if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) { BUG_ON(!extent_op || !extent_op->update_flags); ret = alloc_reserved_tree_block(trans, node, extent_op); } else if (node->action == BTRFS_DROP_DELAYED_REF) { struct btrfs_delayed_tree_ref *ref = btrfs_delayed_node_to_tree_ref(node); ret = __free_extent(trans, node->bytenr, node->num_bytes, ref->parent, ref->root, ref->level, 0, 1); } else { BUG(); } return ret; } /* helper function to actually process a single delayed ref entry */ static int run_one_delayed_ref(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info, struct btrfs_delayed_ref_node *node, struct btrfs_delayed_extent_op *extent_op, int insert_reserved) { int ret = 0; if (node->type == BTRFS_TREE_BLOCK_REF_KEY || node->type == BTRFS_SHARED_BLOCK_REF_KEY) { ret = run_delayed_tree_ref(trans, fs_info, node, extent_op, insert_reserved); } else BUG(); return ret; } int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans, unsigned long nr) { struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_delayed_ref_root *delayed_refs; struct btrfs_delayed_ref_node *ref; struct btrfs_delayed_ref_head *locked_ref = NULL; struct btrfs_delayed_extent_op *extent_op; int ret; int must_insert_reserved = 0; delayed_refs = &trans->delayed_refs; while (1) { if (!locked_ref) { locked_ref = btrfs_select_ref_head(trans); if (!locked_ref) break; } /* * We need to try and merge add/drops of the same ref since we * can run into issues with relocate dropping the implicit ref * and then it being added back again before the drop can * finish. If we merged anything we need to re-loop so we can * get a good ref. * Or we can get node references of the same type that weren't * merged when created due to bumps in the tree mod seq, and * we need to merge them to prevent adding an inline extent * backref before dropping it (triggering a BUG_ON at * insert_inline_extent_backref()). */ btrfs_merge_delayed_refs(trans, delayed_refs, locked_ref); ref = select_delayed_ref(locked_ref); /* * We're done processing refs in this ref_head, clean everything * up and move on to the next ref_head. */ if (!ref) { ret = cleanup_ref_head(trans, fs_info, locked_ref); if (ret > 0 ) { /* We dropped our lock, we need to loop. */ ret = 0; continue; } locked_ref = NULL; continue; } ref->in_tree = 0; rb_erase(&ref->ref_node, &locked_ref->ref_tree); RB_CLEAR_NODE(&ref->ref_node); if (!list_empty(&ref->add_list)) list_del(&ref->add_list); /* * When we play the delayed ref, also correct the ref_mod on * head */ switch (ref->action) { case BTRFS_ADD_DELAYED_REF: case BTRFS_ADD_DELAYED_EXTENT: locked_ref->ref_mod -= ref->ref_mod; break; case BTRFS_DROP_DELAYED_REF: locked_ref->ref_mod += ref->ref_mod; break; default: WARN_ON(1); } /* * Record the must-insert_reserved flag before we drop the spin * lock. */ must_insert_reserved = locked_ref->must_insert_reserved; locked_ref->must_insert_reserved = 0; extent_op = locked_ref->extent_op; locked_ref->extent_op = NULL; ret = run_one_delayed_ref(trans, fs_info, ref, extent_op, must_insert_reserved); btrfs_free_delayed_extent_op(extent_op); /* * If we are re-initing extent tree in this transaction * failure in freeing old roots are expected (because we don't * have the old extent tree, hence backref resolution will * return -EIO). */ if (ret && (!trans->reinit_extent_tree || ref->action != BTRFS_DROP_DELAYED_REF)) { unselect_delayed_ref_head(delayed_refs, locked_ref); btrfs_put_delayed_ref(ref); return ret; } btrfs_put_delayed_ref(ref); } return 0; }