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6179 lines
167 KiB
6179 lines
167 KiB
// SPDX-License-Identifier: GPL-2.0 |
|
/* |
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* Copyright (C) 2007 Oracle. All rights reserved. |
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*/ |
|
|
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#include <linux/sched.h> |
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#include <linux/sched/signal.h> |
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#include <linux/pagemap.h> |
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#include <linux/writeback.h> |
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#include <linux/blkdev.h> |
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#include <linux/sort.h> |
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#include <linux/rcupdate.h> |
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#include <linux/kthread.h> |
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#include <linux/slab.h> |
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#include <linux/ratelimit.h> |
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#include <linux/percpu_counter.h> |
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#include <linux/lockdep.h> |
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#include <linux/crc32c.h> |
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#include "misc.h" |
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#include "tree-log.h" |
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#include "disk-io.h" |
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#include "print-tree.h" |
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#include "volumes.h" |
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#include "raid56.h" |
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#include "locking.h" |
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#include "free-space-cache.h" |
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#include "free-space-tree.h" |
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#include "sysfs.h" |
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#include "qgroup.h" |
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#include "ref-verify.h" |
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#include "space-info.h" |
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#include "block-rsv.h" |
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#include "delalloc-space.h" |
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#include "block-group.h" |
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#include "discard.h" |
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#include "rcu-string.h" |
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#include "zoned.h" |
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#include "dev-replace.h" |
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|
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#undef SCRAMBLE_DELAYED_REFS |
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|
|
|
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static int __btrfs_free_extent(struct btrfs_trans_handle *trans, |
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struct btrfs_delayed_ref_node *node, u64 parent, |
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u64 root_objectid, u64 owner_objectid, |
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u64 owner_offset, int refs_to_drop, |
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struct btrfs_delayed_extent_op *extra_op); |
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static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op, |
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struct extent_buffer *leaf, |
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struct btrfs_extent_item *ei); |
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static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans, |
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u64 parent, u64 root_objectid, |
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u64 flags, u64 owner, u64 offset, |
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struct btrfs_key *ins, int ref_mod); |
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static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans, |
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struct btrfs_delayed_ref_node *node, |
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struct btrfs_delayed_extent_op *extent_op); |
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static int find_next_key(struct btrfs_path *path, int level, |
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struct btrfs_key *key); |
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|
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static int block_group_bits(struct btrfs_block_group *cache, u64 bits) |
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{ |
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return (cache->flags & bits) == bits; |
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} |
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|
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int btrfs_add_excluded_extent(struct btrfs_fs_info *fs_info, |
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u64 start, u64 num_bytes) |
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{ |
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u64 end = start + num_bytes - 1; |
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set_extent_bits(&fs_info->excluded_extents, start, end, |
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EXTENT_UPTODATE); |
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return 0; |
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} |
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|
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void btrfs_free_excluded_extents(struct btrfs_block_group *cache) |
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{ |
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struct btrfs_fs_info *fs_info = cache->fs_info; |
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u64 start, end; |
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|
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start = cache->start; |
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end = start + cache->length - 1; |
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|
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clear_extent_bits(&fs_info->excluded_extents, start, end, |
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EXTENT_UPTODATE); |
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} |
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|
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/* simple helper to search for an existing data extent at a given offset */ |
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int btrfs_lookup_data_extent(struct btrfs_fs_info *fs_info, u64 start, u64 len) |
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{ |
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struct btrfs_root *root = btrfs_extent_root(fs_info, start); |
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int ret; |
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struct btrfs_key key; |
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struct btrfs_path *path; |
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|
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path = btrfs_alloc_path(); |
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if (!path) |
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return -ENOMEM; |
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|
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key.objectid = start; |
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key.offset = len; |
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key.type = BTRFS_EXTENT_ITEM_KEY; |
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ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
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btrfs_free_path(path); |
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return ret; |
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} |
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|
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/* |
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* helper function to lookup reference count and flags of a tree block. |
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* |
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* the head node for delayed ref is used to store the sum of all the |
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* reference count modifications queued up in the rbtree. the head |
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* node may also store the extent flags to set. This way you can check |
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* to see what the reference count and extent flags would be if all of |
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* the delayed refs are not processed. |
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*/ |
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int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans, |
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struct btrfs_fs_info *fs_info, u64 bytenr, |
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u64 offset, int metadata, u64 *refs, u64 *flags) |
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{ |
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struct btrfs_root *extent_root; |
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struct btrfs_delayed_ref_head *head; |
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struct btrfs_delayed_ref_root *delayed_refs; |
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struct btrfs_path *path; |
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struct btrfs_extent_item *ei; |
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struct extent_buffer *leaf; |
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struct btrfs_key key; |
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u32 item_size; |
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u64 num_refs; |
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u64 extent_flags; |
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int ret; |
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|
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/* |
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* If we don't have skinny metadata, don't bother doing anything |
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* different |
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*/ |
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if (metadata && !btrfs_fs_incompat(fs_info, SKINNY_METADATA)) { |
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offset = fs_info->nodesize; |
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metadata = 0; |
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} |
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|
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path = btrfs_alloc_path(); |
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if (!path) |
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return -ENOMEM; |
|
|
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if (!trans) { |
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path->skip_locking = 1; |
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path->search_commit_root = 1; |
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} |
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|
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search_again: |
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key.objectid = bytenr; |
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key.offset = offset; |
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if (metadata) |
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key.type = BTRFS_METADATA_ITEM_KEY; |
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else |
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key.type = BTRFS_EXTENT_ITEM_KEY; |
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|
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extent_root = btrfs_extent_root(fs_info, bytenr); |
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ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0); |
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if (ret < 0) |
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goto out_free; |
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|
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if (ret > 0 && metadata && key.type == BTRFS_METADATA_ITEM_KEY) { |
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if (path->slots[0]) { |
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path->slots[0]--; |
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btrfs_item_key_to_cpu(path->nodes[0], &key, |
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path->slots[0]); |
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if (key.objectid == bytenr && |
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key.type == BTRFS_EXTENT_ITEM_KEY && |
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key.offset == fs_info->nodesize) |
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ret = 0; |
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} |
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} |
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|
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if (ret == 0) { |
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leaf = path->nodes[0]; |
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item_size = btrfs_item_size(leaf, path->slots[0]); |
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if (item_size >= sizeof(*ei)) { |
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ei = btrfs_item_ptr(leaf, path->slots[0], |
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struct btrfs_extent_item); |
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num_refs = btrfs_extent_refs(leaf, ei); |
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extent_flags = btrfs_extent_flags(leaf, ei); |
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} else { |
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ret = -EINVAL; |
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btrfs_print_v0_err(fs_info); |
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if (trans) |
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btrfs_abort_transaction(trans, ret); |
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else |
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btrfs_handle_fs_error(fs_info, ret, NULL); |
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|
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goto out_free; |
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} |
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|
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BUG_ON(num_refs == 0); |
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} else { |
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num_refs = 0; |
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extent_flags = 0; |
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ret = 0; |
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} |
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|
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if (!trans) |
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goto out; |
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|
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delayed_refs = &trans->transaction->delayed_refs; |
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spin_lock(&delayed_refs->lock); |
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head = btrfs_find_delayed_ref_head(delayed_refs, bytenr); |
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if (head) { |
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if (!mutex_trylock(&head->mutex)) { |
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refcount_inc(&head->refs); |
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spin_unlock(&delayed_refs->lock); |
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|
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btrfs_release_path(path); |
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|
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/* |
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* Mutex was contended, block until it's released and try |
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* again |
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*/ |
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mutex_lock(&head->mutex); |
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mutex_unlock(&head->mutex); |
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btrfs_put_delayed_ref_head(head); |
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goto search_again; |
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} |
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spin_lock(&head->lock); |
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if (head->extent_op && head->extent_op->update_flags) |
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extent_flags |= head->extent_op->flags_to_set; |
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else |
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BUG_ON(num_refs == 0); |
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|
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num_refs += head->ref_mod; |
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spin_unlock(&head->lock); |
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mutex_unlock(&head->mutex); |
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} |
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spin_unlock(&delayed_refs->lock); |
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out: |
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WARN_ON(num_refs == 0); |
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if (refs) |
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*refs = num_refs; |
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if (flags) |
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*flags = extent_flags; |
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out_free: |
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btrfs_free_path(path); |
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return ret; |
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} |
|
|
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/* |
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* Back reference rules. Back refs have three main goals: |
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* |
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* 1) differentiate between all holders of references to an extent so that |
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* when a reference is dropped we can make sure it was a valid reference |
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* before freeing the extent. |
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* |
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* 2) Provide enough information to quickly find the holders of an extent |
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* if we notice a given block is corrupted or bad. |
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* |
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* 3) Make it easy to migrate blocks for FS shrinking or storage pool |
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* maintenance. This is actually the same as #2, but with a slightly |
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* different use case. |
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* |
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* There are two kinds of back refs. The implicit back refs is optimized |
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* for pointers in non-shared tree blocks. For a given pointer in a block, |
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* back refs of this kind provide information about the block's owner tree |
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* and the pointer's key. These information allow us to find the block by |
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* b-tree searching. The full back refs is for pointers in tree blocks not |
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* referenced by their owner trees. The location of tree block is recorded |
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* in the back refs. Actually the full back refs is generic, and can be |
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* used in all cases the implicit back refs is used. The major shortcoming |
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* of the full back refs is its overhead. Every time a tree block gets |
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* COWed, we have to update back refs entry for all pointers in it. |
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* |
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* For a newly allocated tree block, we use implicit back refs for |
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* pointers in it. This means most tree related operations only involve |
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* implicit back refs. For a tree block created in old transaction, the |
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* only way to drop a reference to it is COW it. So we can detect the |
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* event that tree block loses its owner tree's reference and do the |
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* back refs conversion. |
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* |
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* When a tree block is COWed through a tree, there are four cases: |
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* |
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* The reference count of the block is one and the tree is the block's |
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* owner tree. Nothing to do in this case. |
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* |
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* The reference count of the block is one and the tree is not the |
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* block's owner tree. In this case, full back refs is used for pointers |
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* in the block. Remove these full back refs, add implicit back refs for |
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* every pointers in the new block. |
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* |
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* The reference count of the block is greater than one and the tree is |
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* the block's owner tree. In this case, implicit back refs is used for |
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* pointers in the block. Add full back refs for every pointers in the |
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* block, increase lower level extents' reference counts. The original |
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* implicit back refs are entailed to the new block. |
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* |
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* The reference count of the block is greater than one and the tree is |
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* not the block's owner tree. Add implicit back refs for every pointer in |
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* the new block, increase lower level extents' reference count. |
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* |
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* Back Reference Key composing: |
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* |
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* The key objectid corresponds to the first byte in the extent, |
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* The key type is used to differentiate between types of back refs. |
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* There are different meanings of the key offset for different types |
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* of back refs. |
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* |
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* File extents can be referenced by: |
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* |
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* - multiple snapshots, subvolumes, or different generations in one subvol |
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* - different files inside a single subvolume |
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* - different offsets inside a file (bookend extents in file.c) |
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* |
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* The extent ref structure for the implicit back refs has fields for: |
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* |
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* - Objectid of the subvolume root |
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* - objectid of the file holding the reference |
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* - original offset in the file |
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* - how many bookend extents |
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* |
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* The key offset for the implicit back refs is hash of the first |
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* three fields. |
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* |
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* The extent ref structure for the full back refs has field for: |
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* |
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* - number of pointers in the tree leaf |
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* |
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* The key offset for the implicit back refs is the first byte of |
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* the tree leaf |
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* |
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* When a file extent is allocated, The implicit back refs is used. |
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* the fields are filled in: |
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* |
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* (root_key.objectid, inode objectid, offset in file, 1) |
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* |
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* When a file extent is removed file truncation, we find the |
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* corresponding implicit back refs and check the following fields: |
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* |
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* (btrfs_header_owner(leaf), inode objectid, offset in file) |
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* |
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* Btree extents can be referenced by: |
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* |
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* - Different subvolumes |
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* |
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* 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 |
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* is the first byte of parent block. |
|
* |
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* When implicit back refs is used, information about the lowest key and |
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* level of the tree block are required. These information are stored in |
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* tree block info structure. |
|
*/ |
|
|
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/* |
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* is_data == BTRFS_REF_TYPE_BLOCK, tree block type is required, |
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* is_data == BTRFS_REF_TYPE_DATA, data type is requiried, |
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* is_data == BTRFS_REF_TYPE_ANY, either type is OK. |
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*/ |
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int btrfs_get_extent_inline_ref_type(const struct extent_buffer *eb, |
|
struct btrfs_extent_inline_ref *iref, |
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enum btrfs_inline_ref_type is_data) |
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{ |
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int type = btrfs_extent_inline_ref_type(eb, iref); |
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u64 offset = btrfs_extent_inline_ref_offset(eb, iref); |
|
|
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if (type == BTRFS_TREE_BLOCK_REF_KEY || |
|
type == BTRFS_SHARED_BLOCK_REF_KEY || |
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type == BTRFS_SHARED_DATA_REF_KEY || |
|
type == BTRFS_EXTENT_DATA_REF_KEY) { |
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if (is_data == BTRFS_REF_TYPE_BLOCK) { |
|
if (type == BTRFS_TREE_BLOCK_REF_KEY) |
|
return type; |
|
if (type == BTRFS_SHARED_BLOCK_REF_KEY) { |
|
ASSERT(eb->fs_info); |
|
/* |
|
* Every shared one has parent tree block, |
|
* which must be aligned to sector size. |
|
*/ |
|
if (offset && |
|
IS_ALIGNED(offset, eb->fs_info->sectorsize)) |
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return type; |
|
} |
|
} else if (is_data == BTRFS_REF_TYPE_DATA) { |
|
if (type == BTRFS_EXTENT_DATA_REF_KEY) |
|
return type; |
|
if (type == BTRFS_SHARED_DATA_REF_KEY) { |
|
ASSERT(eb->fs_info); |
|
/* |
|
* Every shared one has parent tree block, |
|
* which must be aligned to sector size. |
|
*/ |
|
if (offset && |
|
IS_ALIGNED(offset, eb->fs_info->sectorsize)) |
|
return type; |
|
} |
|
} else { |
|
ASSERT(is_data == BTRFS_REF_TYPE_ANY); |
|
return type; |
|
} |
|
} |
|
|
|
btrfs_print_leaf((struct extent_buffer *)eb); |
|
btrfs_err(eb->fs_info, |
|
"eb %llu iref 0x%lx invalid extent inline ref type %d", |
|
eb->start, (unsigned long)iref, type); |
|
WARN_ON(1); |
|
|
|
return BTRFS_REF_TYPE_INVALID; |
|
} |
|
|
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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_path *path, |
|
u64 bytenr, u64 parent, |
|
u64 root_objectid, |
|
u64 owner, u64 offset) |
|
{ |
|
struct btrfs_root *root = btrfs_extent_root(trans->fs_info, bytenr); |
|
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_path *path, |
|
u64 bytenr, u64 parent, |
|
u64 root_objectid, u64 owner, |
|
u64 offset, int refs_to_add) |
|
{ |
|
struct btrfs_root *root = btrfs_extent_root(trans->fs_info, bytenr); |
|
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, int *last_ref) |
|
{ |
|
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 if (unlikely(key.type == BTRFS_EXTENT_REF_V0_KEY)) { |
|
btrfs_print_v0_err(trans->fs_info); |
|
btrfs_abort_transaction(trans, -EINVAL); |
|
return -EINVAL; |
|
} 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); |
|
*last_ref = 1; |
|
} 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; |
|
int type; |
|
|
|
leaf = path->nodes[0]; |
|
btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); |
|
|
|
BUG_ON(key.type == BTRFS_EXTENT_REF_V0_KEY); |
|
if (iref) { |
|
/* |
|
* If type is invalid, we should have bailed out earlier than |
|
* this call. |
|
*/ |
|
type = btrfs_get_extent_inline_ref_type(leaf, iref, BTRFS_REF_TYPE_DATA); |
|
ASSERT(type != BTRFS_REF_TYPE_INVALID); |
|
if (type == 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 { |
|
WARN_ON(1); |
|
} |
|
return num_refs; |
|
} |
|
|
|
static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans, |
|
struct btrfs_path *path, |
|
u64 bytenr, u64 parent, |
|
u64 root_objectid) |
|
{ |
|
struct btrfs_root *root = btrfs_extent_root(trans->fs_info, bytenr); |
|
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_path *path, |
|
u64 bytenr, u64 parent, |
|
u64 root_objectid) |
|
{ |
|
struct btrfs_root *root = btrfs_extent_root(trans->fs_info, bytenr); |
|
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 find_next_key(struct btrfs_path *path, int level, |
|
struct btrfs_key *key) |
|
|
|
{ |
|
for (; level < BTRFS_MAX_LEVEL; level++) { |
|
if (!path->nodes[level]) |
|
break; |
|
if (path->slots[level] + 1 >= |
|
btrfs_header_nritems(path->nodes[level])) |
|
continue; |
|
if (level == 0) |
|
btrfs_item_key_to_cpu(path->nodes[level], key, |
|
path->slots[level] + 1); |
|
else |
|
btrfs_node_key_to_cpu(path->nodes[level], key, |
|
path->slots[level] + 1); |
|
return 0; |
|
} |
|
return 1; |
|
} |
|
|
|
/* |
|
* look for inline back ref. if back ref is found, *ref_ret is set |
|
* to the address of inline back ref, and 0 is returned. |
|
* |
|
* if back ref isn't found, *ref_ret is set to the address where it |
|
* should be inserted, and -ENOENT is returned. |
|
* |
|
* if insert is true and there are too many inline back refs, the path |
|
* points to the extent item, and -EAGAIN is returned. |
|
* |
|
* NOTE: inline back refs are ordered in the same way that back ref |
|
* items in the tree are ordered. |
|
*/ |
|
static noinline_for_stack |
|
int lookup_inline_extent_backref(struct btrfs_trans_handle *trans, |
|
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_fs_info *fs_info = trans->fs_info; |
|
struct btrfs_root *root = btrfs_extent_root(fs_info, bytenr); |
|
struct btrfs_key key; |
|
struct extent_buffer *leaf; |
|
struct btrfs_extent_item *ei; |
|
struct btrfs_extent_inline_ref *iref; |
|
u64 flags; |
|
u64 item_size; |
|
unsigned long ptr; |
|
unsigned long end; |
|
int extra_size; |
|
int type; |
|
int want; |
|
int ret; |
|
int err = 0; |
|
bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA); |
|
int needed; |
|
|
|
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); |
|
path->search_for_extension = 1; |
|
path->keep_locks = 1; |
|
} else |
|
extra_size = -1; |
|
|
|
/* |
|
* Owner is our level, so we can just add one to get the level for the |
|
* block we are interested in. |
|
*/ |
|
if (skinny_metadata && owner < BTRFS_FIRST_FREE_OBJECTID) { |
|
key.type = BTRFS_METADATA_ITEM_KEY; |
|
key.offset = owner; |
|
} |
|
|
|
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 = false; |
|
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.objectid = bytenr; |
|
key.type = BTRFS_EXTENT_ITEM_KEY; |
|
key.offset = num_bytes; |
|
btrfs_release_path(path); |
|
goto again; |
|
} |
|
} |
|
|
|
if (ret && !insert) { |
|
err = -ENOENT; |
|
goto out; |
|
} else if (WARN_ON(ret)) { |
|
err = -EIO; |
|
goto out; |
|
} |
|
|
|
leaf = path->nodes[0]; |
|
item_size = btrfs_item_size(leaf, path->slots[0]); |
|
if (unlikely(item_size < sizeof(*ei))) { |
|
err = -EINVAL; |
|
btrfs_print_v0_err(fs_info); |
|
btrfs_abort_transaction(trans, err); |
|
goto out; |
|
} |
|
|
|
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); |
|
} |
|
|
|
if (owner >= BTRFS_FIRST_FREE_OBJECTID) |
|
needed = BTRFS_REF_TYPE_DATA; |
|
else |
|
needed = BTRFS_REF_TYPE_BLOCK; |
|
|
|
err = -ENOENT; |
|
while (1) { |
|
if (ptr >= end) { |
|
WARN_ON(ptr > end); |
|
break; |
|
} |
|
iref = (struct btrfs_extent_inline_ref *)ptr; |
|
type = btrfs_get_extent_inline_ref_type(leaf, iref, needed); |
|
if (type == BTRFS_REF_TYPE_INVALID) { |
|
err = -EUCLEAN; |
|
goto out; |
|
} |
|
|
|
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 kind of item for this block |
|
*/ |
|
if (find_next_key(path, 0, &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: |
|
if (insert) { |
|
path->keep_locks = 0; |
|
path->search_for_extension = 0; |
|
btrfs_unlock_up_safe(path, 1); |
|
} |
|
return err; |
|
} |
|
|
|
/* |
|
* helper to add new inline back ref |
|
*/ |
|
static noinline_for_stack |
|
void setup_inline_extent_backref(struct btrfs_fs_info *fs_info, |
|
struct btrfs_path *path, |
|
struct btrfs_extent_inline_ref *iref, |
|
u64 parent, u64 root_objectid, |
|
u64 owner, u64 offset, int refs_to_add, |
|
struct btrfs_delayed_extent_op *extent_op) |
|
{ |
|
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; |
|
|
|
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); |
|
|
|
btrfs_extend_item(path, size); |
|
|
|
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); |
|
if (extent_op) |
|
__run_delayed_extent_op(extent_op, leaf, ei); |
|
|
|
ptr = (unsigned long)ei + item_offset; |
|
end = (unsigned long)ei + btrfs_item_size(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); |
|
} |
|
|
|
static int lookup_extent_backref(struct btrfs_trans_handle *trans, |
|
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, 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, path, bytenr, parent, |
|
root_objectid); |
|
} else { |
|
ret = lookup_extent_data_ref(trans, path, bytenr, parent, |
|
root_objectid, owner, offset); |
|
} |
|
return ret; |
|
} |
|
|
|
/* |
|
* helper to update/remove inline back ref |
|
*/ |
|
static noinline_for_stack |
|
void update_inline_extent_backref(struct btrfs_path *path, |
|
struct btrfs_extent_inline_ref *iref, |
|
int refs_to_mod, |
|
struct btrfs_delayed_extent_op *extent_op, |
|
int *last_ref) |
|
{ |
|
struct extent_buffer *leaf = path->nodes[0]; |
|
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; |
|
u64 refs; |
|
|
|
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); |
|
if (extent_op) |
|
__run_delayed_extent_op(extent_op, leaf, ei); |
|
|
|
/* |
|
* If type is invalid, we should have bailed out after |
|
* lookup_inline_extent_backref(). |
|
*/ |
|
type = btrfs_get_extent_inline_ref_type(leaf, iref, BTRFS_REF_TYPE_ANY); |
|
ASSERT(type != BTRFS_REF_TYPE_INVALID); |
|
|
|
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 { |
|
*last_ref = 1; |
|
size = btrfs_extent_inline_ref_size(type); |
|
item_size = btrfs_item_size(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; |
|
btrfs_truncate_item(path, item_size, 1); |
|
} |
|
btrfs_mark_buffer_dirty(leaf); |
|
} |
|
|
|
static noinline_for_stack |
|
int insert_inline_extent_backref(struct btrfs_trans_handle *trans, |
|
struct btrfs_path *path, |
|
u64 bytenr, u64 num_bytes, u64 parent, |
|
u64 root_objectid, u64 owner, |
|
u64 offset, int refs_to_add, |
|
struct btrfs_delayed_extent_op *extent_op) |
|
{ |
|
struct btrfs_extent_inline_ref *iref; |
|
int ret; |
|
|
|
ret = lookup_inline_extent_backref(trans, path, &iref, bytenr, |
|
num_bytes, parent, root_objectid, |
|
owner, offset, 1); |
|
if (ret == 0) { |
|
/* |
|
* We're adding refs to a tree block we already own, this |
|
* should not happen at all. |
|
*/ |
|
if (owner < BTRFS_FIRST_FREE_OBJECTID) { |
|
btrfs_crit(trans->fs_info, |
|
"adding refs to an existing tree ref, bytenr %llu num_bytes %llu root_objectid %llu", |
|
bytenr, num_bytes, root_objectid); |
|
if (IS_ENABLED(CONFIG_BTRFS_DEBUG)) { |
|
WARN_ON(1); |
|
btrfs_crit(trans->fs_info, |
|
"path->slots[0]=%d path->nodes[0]:", path->slots[0]); |
|
btrfs_print_leaf(path->nodes[0]); |
|
} |
|
return -EUCLEAN; |
|
} |
|
update_inline_extent_backref(path, iref, refs_to_add, |
|
extent_op, NULL); |
|
} else if (ret == -ENOENT) { |
|
setup_inline_extent_backref(trans->fs_info, path, iref, parent, |
|
root_objectid, owner, offset, |
|
refs_to_add, extent_op); |
|
ret = 0; |
|
} |
|
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 *last_ref) |
|
{ |
|
int ret = 0; |
|
|
|
BUG_ON(!is_data && refs_to_drop != 1); |
|
if (iref) { |
|
update_inline_extent_backref(path, iref, -refs_to_drop, NULL, |
|
last_ref); |
|
} else if (is_data) { |
|
ret = remove_extent_data_ref(trans, root, path, refs_to_drop, |
|
last_ref); |
|
} else { |
|
*last_ref = 1; |
|
ret = btrfs_del_item(trans, root, path); |
|
} |
|
return ret; |
|
} |
|
|
|
static int btrfs_issue_discard(struct block_device *bdev, u64 start, u64 len, |
|
u64 *discarded_bytes) |
|
{ |
|
int j, ret = 0; |
|
u64 bytes_left, end; |
|
u64 aligned_start = ALIGN(start, 1 << 9); |
|
|
|
if (WARN_ON(start != aligned_start)) { |
|
len -= aligned_start - start; |
|
len = round_down(len, 1 << 9); |
|
start = aligned_start; |
|
} |
|
|
|
*discarded_bytes = 0; |
|
|
|
if (!len) |
|
return 0; |
|
|
|
end = start + len; |
|
bytes_left = len; |
|
|
|
/* Skip any superblocks on this device. */ |
|
for (j = 0; j < BTRFS_SUPER_MIRROR_MAX; j++) { |
|
u64 sb_start = btrfs_sb_offset(j); |
|
u64 sb_end = sb_start + BTRFS_SUPER_INFO_SIZE; |
|
u64 size = sb_start - start; |
|
|
|
if (!in_range(sb_start, start, bytes_left) && |
|
!in_range(sb_end, start, bytes_left) && |
|
!in_range(start, sb_start, BTRFS_SUPER_INFO_SIZE)) |
|
continue; |
|
|
|
/* |
|
* Superblock spans beginning of range. Adjust start and |
|
* try again. |
|
*/ |
|
if (sb_start <= start) { |
|
start += sb_end - start; |
|
if (start > end) { |
|
bytes_left = 0; |
|
break; |
|
} |
|
bytes_left = end - start; |
|
continue; |
|
} |
|
|
|
if (size) { |
|
ret = blkdev_issue_discard(bdev, start >> 9, size >> 9, |
|
GFP_NOFS, 0); |
|
if (!ret) |
|
*discarded_bytes += size; |
|
else if (ret != -EOPNOTSUPP) |
|
return ret; |
|
} |
|
|
|
start = sb_end; |
|
if (start > end) { |
|
bytes_left = 0; |
|
break; |
|
} |
|
bytes_left = end - start; |
|
} |
|
|
|
if (bytes_left) { |
|
ret = blkdev_issue_discard(bdev, start >> 9, bytes_left >> 9, |
|
GFP_NOFS, 0); |
|
if (!ret) |
|
*discarded_bytes += bytes_left; |
|
} |
|
return ret; |
|
} |
|
|
|
static int do_discard_extent(struct btrfs_io_stripe *stripe, u64 *bytes) |
|
{ |
|
struct btrfs_device *dev = stripe->dev; |
|
struct btrfs_fs_info *fs_info = dev->fs_info; |
|
struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; |
|
u64 phys = stripe->physical; |
|
u64 len = stripe->length; |
|
u64 discarded = 0; |
|
int ret = 0; |
|
|
|
/* Zone reset on a zoned filesystem */ |
|
if (btrfs_can_zone_reset(dev, phys, len)) { |
|
u64 src_disc; |
|
|
|
ret = btrfs_reset_device_zone(dev, phys, len, &discarded); |
|
if (ret) |
|
goto out; |
|
|
|
if (!btrfs_dev_replace_is_ongoing(dev_replace) || |
|
dev != dev_replace->srcdev) |
|
goto out; |
|
|
|
src_disc = discarded; |
|
|
|
/* Send to replace target as well */ |
|
ret = btrfs_reset_device_zone(dev_replace->tgtdev, phys, len, |
|
&discarded); |
|
discarded += src_disc; |
|
} else if (blk_queue_discard(bdev_get_queue(stripe->dev->bdev))) { |
|
ret = btrfs_issue_discard(dev->bdev, phys, len, &discarded); |
|
} else { |
|
ret = 0; |
|
*bytes = 0; |
|
} |
|
|
|
out: |
|
*bytes = discarded; |
|
return ret; |
|
} |
|
|
|
int btrfs_discard_extent(struct btrfs_fs_info *fs_info, u64 bytenr, |
|
u64 num_bytes, u64 *actual_bytes) |
|
{ |
|
int ret = 0; |
|
u64 discarded_bytes = 0; |
|
u64 end = bytenr + num_bytes; |
|
u64 cur = bytenr; |
|
struct btrfs_io_context *bioc = NULL; |
|
|
|
/* |
|
* Avoid races with device replace and make sure our bioc has devices |
|
* associated to its stripes that don't go away while we are discarding. |
|
*/ |
|
btrfs_bio_counter_inc_blocked(fs_info); |
|
while (cur < end) { |
|
struct btrfs_io_stripe *stripe; |
|
int i; |
|
|
|
num_bytes = end - cur; |
|
/* Tell the block device(s) that the sectors can be discarded */ |
|
ret = btrfs_map_block(fs_info, BTRFS_MAP_DISCARD, cur, |
|
&num_bytes, &bioc, 0); |
|
/* |
|
* Error can be -ENOMEM, -ENOENT (no such chunk mapping) or |
|
* -EOPNOTSUPP. For any such error, @num_bytes is not updated, |
|
* thus we can't continue anyway. |
|
*/ |
|
if (ret < 0) |
|
goto out; |
|
|
|
stripe = bioc->stripes; |
|
for (i = 0; i < bioc->num_stripes; i++, stripe++) { |
|
u64 bytes; |
|
struct btrfs_device *device = stripe->dev; |
|
|
|
if (!device->bdev) { |
|
ASSERT(btrfs_test_opt(fs_info, DEGRADED)); |
|
continue; |
|
} |
|
|
|
if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) |
|
continue; |
|
|
|
ret = do_discard_extent(stripe, &bytes); |
|
if (!ret) { |
|
discarded_bytes += bytes; |
|
} else if (ret != -EOPNOTSUPP) { |
|
/* |
|
* Logic errors or -ENOMEM, or -EIO, but |
|
* unlikely to happen. |
|
* |
|
* And since there are two loops, explicitly |
|
* go to out to avoid confusion. |
|
*/ |
|
btrfs_put_bioc(bioc); |
|
goto out; |
|
} |
|
|
|
/* |
|
* Just in case we get back EOPNOTSUPP for some reason, |
|
* just ignore the return value so we don't screw up |
|
* people calling discard_extent. |
|
*/ |
|
ret = 0; |
|
} |
|
btrfs_put_bioc(bioc); |
|
cur += num_bytes; |
|
} |
|
out: |
|
btrfs_bio_counter_dec(fs_info); |
|
|
|
if (actual_bytes) |
|
*actual_bytes = discarded_bytes; |
|
|
|
|
|
if (ret == -EOPNOTSUPP) |
|
ret = 0; |
|
return ret; |
|
} |
|
|
|
/* Can return -ENOMEM */ |
|
int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans, |
|
struct btrfs_ref *generic_ref) |
|
{ |
|
struct btrfs_fs_info *fs_info = trans->fs_info; |
|
int ret; |
|
|
|
ASSERT(generic_ref->type != BTRFS_REF_NOT_SET && |
|
generic_ref->action); |
|
BUG_ON(generic_ref->type == BTRFS_REF_METADATA && |
|
generic_ref->tree_ref.owning_root == BTRFS_TREE_LOG_OBJECTID); |
|
|
|
if (generic_ref->type == BTRFS_REF_METADATA) |
|
ret = btrfs_add_delayed_tree_ref(trans, generic_ref, NULL); |
|
else |
|
ret = btrfs_add_delayed_data_ref(trans, generic_ref, 0); |
|
|
|
btrfs_ref_tree_mod(fs_info, generic_ref); |
|
|
|
return ret; |
|
} |
|
|
|
/* |
|
* __btrfs_inc_extent_ref - insert backreference for a given extent |
|
* |
|
* The counterpart is in __btrfs_free_extent(), with examples and more details |
|
* how it works. |
|
* |
|
* @trans: Handle of transaction |
|
* |
|
* @node: The delayed ref node used to get the bytenr/length for |
|
* extent whose references are incremented. |
|
* |
|
* @parent: If this is a shared extent (BTRFS_SHARED_DATA_REF_KEY/ |
|
* BTRFS_SHARED_BLOCK_REF_KEY) then it holds the logical |
|
* bytenr of the parent block. Since new extents are always |
|
* created with indirect references, this will only be the case |
|
* when relocating a shared extent. In that case, root_objectid |
|
* will be BTRFS_TREE_RELOC_OBJECTID. Otherwise, parent must |
|
* be 0 |
|
* |
|
* @root_objectid: The id of the root where this modification has originated, |
|
* this can be either one of the well-known metadata trees or |
|
* the subvolume id which references this extent. |
|
* |
|
* @owner: For data extents it is the inode number of the owning file. |
|
* For metadata extents this parameter holds the level in the |
|
* tree of the extent. |
|
* |
|
* @offset: For metadata extents the offset is ignored and is currently |
|
* always passed as 0. For data extents it is the fileoffset |
|
* this extent belongs to. |
|
* |
|
* @refs_to_add Number of references to add |
|
* |
|
* @extent_op Pointer to a structure, holding information necessary when |
|
* updating a tree block's flags |
|
* |
|
*/ |
|
static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans, |
|
struct btrfs_delayed_ref_node *node, |
|
u64 parent, u64 root_objectid, |
|
u64 owner, u64 offset, int refs_to_add, |
|
struct btrfs_delayed_extent_op *extent_op) |
|
{ |
|
struct btrfs_path *path; |
|
struct extent_buffer *leaf; |
|
struct btrfs_extent_item *item; |
|
struct btrfs_key key; |
|
u64 bytenr = node->bytenr; |
|
u64 num_bytes = node->num_bytes; |
|
u64 refs; |
|
int ret; |
|
|
|
path = btrfs_alloc_path(); |
|
if (!path) |
|
return -ENOMEM; |
|
|
|
/* this will setup the path even if it fails to insert the back ref */ |
|
ret = insert_inline_extent_backref(trans, path, bytenr, num_bytes, |
|
parent, root_objectid, owner, |
|
offset, refs_to_add, extent_op); |
|
if ((ret < 0 && ret != -EAGAIN) || !ret) |
|
goto out; |
|
|
|
/* |
|
* Ok we had -EAGAIN which means we didn't have space to insert and |
|
* inline extent ref, so just update the reference count and add a |
|
* normal backref. |
|
*/ |
|
leaf = path->nodes[0]; |
|
btrfs_item_key_to_cpu(leaf, &key, path->slots[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 + refs_to_add); |
|
if (extent_op) |
|
__run_delayed_extent_op(extent_op, leaf, item); |
|
|
|
btrfs_mark_buffer_dirty(leaf); |
|
btrfs_release_path(path); |
|
|
|
/* now insert the actual backref */ |
|
if (owner < BTRFS_FIRST_FREE_OBJECTID) { |
|
BUG_ON(refs_to_add != 1); |
|
ret = insert_tree_block_ref(trans, path, bytenr, parent, |
|
root_objectid); |
|
} else { |
|
ret = insert_extent_data_ref(trans, path, bytenr, parent, |
|
root_objectid, owner, offset, |
|
refs_to_add); |
|
} |
|
if (ret) |
|
btrfs_abort_transaction(trans, ret); |
|
out: |
|
btrfs_free_path(path); |
|
return ret; |
|
} |
|
|
|
static int run_delayed_data_ref(struct btrfs_trans_handle *trans, |
|
struct btrfs_delayed_ref_node *node, |
|
struct btrfs_delayed_extent_op *extent_op, |
|
int insert_reserved) |
|
{ |
|
int ret = 0; |
|
struct btrfs_delayed_data_ref *ref; |
|
struct btrfs_key ins; |
|
u64 parent = 0; |
|
u64 ref_root = 0; |
|
u64 flags = 0; |
|
|
|
ins.objectid = node->bytenr; |
|
ins.offset = node->num_bytes; |
|
ins.type = BTRFS_EXTENT_ITEM_KEY; |
|
|
|
ref = btrfs_delayed_node_to_data_ref(node); |
|
trace_run_delayed_data_ref(trans->fs_info, node, ref, node->action); |
|
|
|
if (node->type == BTRFS_SHARED_DATA_REF_KEY) |
|
parent = ref->parent; |
|
ref_root = ref->root; |
|
|
|
if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) { |
|
if (extent_op) |
|
flags |= extent_op->flags_to_set; |
|
ret = alloc_reserved_file_extent(trans, parent, ref_root, |
|
flags, ref->objectid, |
|
ref->offset, &ins, |
|
node->ref_mod); |
|
} else if (node->action == BTRFS_ADD_DELAYED_REF) { |
|
ret = __btrfs_inc_extent_ref(trans, node, parent, ref_root, |
|
ref->objectid, ref->offset, |
|
node->ref_mod, extent_op); |
|
} else if (node->action == BTRFS_DROP_DELAYED_REF) { |
|
ret = __btrfs_free_extent(trans, node, parent, |
|
ref_root, ref->objectid, |
|
ref->offset, node->ref_mod, |
|
extent_op); |
|
} else { |
|
BUG(); |
|
} |
|
return ret; |
|
} |
|
|
|
static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op, |
|
struct extent_buffer *leaf, |
|
struct btrfs_extent_item *ei) |
|
{ |
|
u64 flags = btrfs_extent_flags(leaf, ei); |
|
if (extent_op->update_flags) { |
|
flags |= extent_op->flags_to_set; |
|
btrfs_set_extent_flags(leaf, ei, flags); |
|
} |
|
|
|
if (extent_op->update_key) { |
|
struct btrfs_tree_block_info *bi; |
|
BUG_ON(!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)); |
|
bi = (struct btrfs_tree_block_info *)(ei + 1); |
|
btrfs_set_tree_block_key(leaf, bi, &extent_op->key); |
|
} |
|
} |
|
|
|
static int run_delayed_extent_op(struct btrfs_trans_handle *trans, |
|
struct btrfs_delayed_ref_head *head, |
|
struct btrfs_delayed_extent_op *extent_op) |
|
{ |
|
struct btrfs_fs_info *fs_info = trans->fs_info; |
|
struct btrfs_root *root; |
|
struct btrfs_key key; |
|
struct btrfs_path *path; |
|
struct btrfs_extent_item *ei; |
|
struct extent_buffer *leaf; |
|
u32 item_size; |
|
int ret; |
|
int err = 0; |
|
int metadata = !extent_op->is_data; |
|
|
|
if (TRANS_ABORTED(trans)) |
|
return 0; |
|
|
|
if (metadata && !btrfs_fs_incompat(fs_info, SKINNY_METADATA)) |
|
metadata = 0; |
|
|
|
path = btrfs_alloc_path(); |
|
if (!path) |
|
return -ENOMEM; |
|
|
|
key.objectid = head->bytenr; |
|
|
|
if (metadata) { |
|
key.type = BTRFS_METADATA_ITEM_KEY; |
|
key.offset = extent_op->level; |
|
} else { |
|
key.type = BTRFS_EXTENT_ITEM_KEY; |
|
key.offset = head->num_bytes; |
|
} |
|
|
|
root = btrfs_extent_root(fs_info, key.objectid); |
|
again: |
|
ret = btrfs_search_slot(trans, root, &key, path, 0, 1); |
|
if (ret < 0) { |
|
err = ret; |
|
goto out; |
|
} |
|
if (ret > 0) { |
|
if (metadata) { |
|
if (path->slots[0] > 0) { |
|
path->slots[0]--; |
|
btrfs_item_key_to_cpu(path->nodes[0], &key, |
|
path->slots[0]); |
|
if (key.objectid == head->bytenr && |
|
key.type == BTRFS_EXTENT_ITEM_KEY && |
|
key.offset == head->num_bytes) |
|
ret = 0; |
|
} |
|
if (ret > 0) { |
|
btrfs_release_path(path); |
|
metadata = 0; |
|
|
|
key.objectid = head->bytenr; |
|
key.offset = head->num_bytes; |
|
key.type = BTRFS_EXTENT_ITEM_KEY; |
|
goto again; |
|
} |
|
} else { |
|
err = -EIO; |
|
goto out; |
|
} |
|
} |
|
|
|
leaf = path->nodes[0]; |
|
item_size = btrfs_item_size(leaf, path->slots[0]); |
|
|
|
if (unlikely(item_size < sizeof(*ei))) { |
|
err = -EINVAL; |
|
btrfs_print_v0_err(fs_info); |
|
btrfs_abort_transaction(trans, err); |
|
goto out; |
|
} |
|
|
|
ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item); |
|
__run_delayed_extent_op(extent_op, leaf, ei); |
|
|
|
btrfs_mark_buffer_dirty(leaf); |
|
out: |
|
btrfs_free_path(path); |
|
return err; |
|
} |
|
|
|
static int run_delayed_tree_ref(struct btrfs_trans_handle *trans, |
|
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); |
|
trace_run_delayed_tree_ref(trans->fs_info, node, ref, node->action); |
|
|
|
if (node->type == BTRFS_SHARED_BLOCK_REF_KEY) |
|
parent = ref->parent; |
|
ref_root = ref->root; |
|
|
|
if (node->ref_mod != 1) { |
|
btrfs_err(trans->fs_info, |
|
"btree block(%llu) has %d references rather than 1: action %d 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_ADD_DELAYED_REF) { |
|
ret = __btrfs_inc_extent_ref(trans, node, parent, ref_root, |
|
ref->level, 0, 1, extent_op); |
|
} else if (node->action == BTRFS_DROP_DELAYED_REF) { |
|
ret = __btrfs_free_extent(trans, node, parent, ref_root, |
|
ref->level, 0, 1, extent_op); |
|
} 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_delayed_ref_node *node, |
|
struct btrfs_delayed_extent_op *extent_op, |
|
int insert_reserved) |
|
{ |
|
int ret = 0; |
|
|
|
if (TRANS_ABORTED(trans)) { |
|
if (insert_reserved) |
|
btrfs_pin_extent(trans, node->bytenr, node->num_bytes, 1); |
|
return 0; |
|
} |
|
|
|
if (node->type == BTRFS_TREE_BLOCK_REF_KEY || |
|
node->type == BTRFS_SHARED_BLOCK_REF_KEY) |
|
ret = run_delayed_tree_ref(trans, node, extent_op, |
|
insert_reserved); |
|
else if (node->type == BTRFS_EXTENT_DATA_REF_KEY || |
|
node->type == BTRFS_SHARED_DATA_REF_KEY) |
|
ret = run_delayed_data_ref(trans, node, extent_op, |
|
insert_reserved); |
|
else |
|
BUG(); |
|
if (ret && insert_reserved) |
|
btrfs_pin_extent(trans, node->bytenr, node->num_bytes, 1); |
|
return ret; |
|
} |
|
|
|
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.rb_root)) |
|
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_cached(&head->ref_tree), |
|
struct btrfs_delayed_ref_node, ref_node); |
|
ASSERT(list_empty(&ref->add_list)); |
|
return ref; |
|
} |
|
|
|
static void unselect_delayed_ref_head(struct btrfs_delayed_ref_root *delayed_refs, |
|
struct btrfs_delayed_ref_head *head) |
|
{ |
|
spin_lock(&delayed_refs->lock); |
|
head->processing = 0; |
|
delayed_refs->num_heads_ready++; |
|
spin_unlock(&delayed_refs->lock); |
|
btrfs_delayed_ref_unlock(head); |
|
} |
|
|
|
static struct btrfs_delayed_extent_op *cleanup_extent_op( |
|
struct btrfs_delayed_ref_head *head) |
|
{ |
|
struct btrfs_delayed_extent_op *extent_op = head->extent_op; |
|
|
|
if (!extent_op) |
|
return NULL; |
|
|
|
if (head->must_insert_reserved) { |
|
head->extent_op = NULL; |
|
btrfs_free_delayed_extent_op(extent_op); |
|
return NULL; |
|
} |
|
return extent_op; |
|
} |
|
|
|
static int run_and_cleanup_extent_op(struct btrfs_trans_handle *trans, |
|
struct btrfs_delayed_ref_head *head) |
|
{ |
|
struct btrfs_delayed_extent_op *extent_op; |
|
int ret; |
|
|
|
extent_op = cleanup_extent_op(head); |
|
if (!extent_op) |
|
return 0; |
|
head->extent_op = NULL; |
|
spin_unlock(&head->lock); |
|
ret = run_delayed_extent_op(trans, head, extent_op); |
|
btrfs_free_delayed_extent_op(extent_op); |
|
return ret ? ret : 1; |
|
} |
|
|
|
void btrfs_cleanup_ref_head_accounting(struct btrfs_fs_info *fs_info, |
|
struct btrfs_delayed_ref_root *delayed_refs, |
|
struct btrfs_delayed_ref_head *head) |
|
{ |
|
int nr_items = 1; /* Dropping this ref head update. */ |
|
|
|
/* |
|
* We had csum deletions accounted for in our delayed refs rsv, we need |
|
* to drop the csum leaves for this update from our delayed_refs_rsv. |
|
*/ |
|
if (head->total_ref_mod < 0 && head->is_data) { |
|
spin_lock(&delayed_refs->lock); |
|
delayed_refs->pending_csums -= head->num_bytes; |
|
spin_unlock(&delayed_refs->lock); |
|
nr_items += btrfs_csum_bytes_to_leaves(fs_info, head->num_bytes); |
|
} |
|
|
|
btrfs_delayed_refs_rsv_release(fs_info, nr_items); |
|
} |
|
|
|
static int cleanup_ref_head(struct btrfs_trans_handle *trans, |
|
struct btrfs_delayed_ref_head *head) |
|
{ |
|
|
|
struct btrfs_fs_info *fs_info = trans->fs_info; |
|
struct btrfs_delayed_ref_root *delayed_refs; |
|
int ret; |
|
|
|
delayed_refs = &trans->transaction->delayed_refs; |
|
|
|
ret = run_and_cleanup_extent_op(trans, head); |
|
if (ret < 0) { |
|
unselect_delayed_ref_head(delayed_refs, head); |
|
btrfs_debug(fs_info, "run_delayed_extent_op returned %d", ret); |
|
return ret; |
|
} else if (ret) { |
|
return ret; |
|
} |
|
|
|
/* |
|
* Need to drop our head ref lock and re-acquire the delayed ref lock |
|
* and then re-check to make sure nobody got added. |
|
*/ |
|
spin_unlock(&head->lock); |
|
spin_lock(&delayed_refs->lock); |
|
spin_lock(&head->lock); |
|
if (!RB_EMPTY_ROOT(&head->ref_tree.rb_root) || head->extent_op) { |
|
spin_unlock(&head->lock); |
|
spin_unlock(&delayed_refs->lock); |
|
return 1; |
|
} |
|
btrfs_delete_ref_head(delayed_refs, head); |
|
spin_unlock(&head->lock); |
|
spin_unlock(&delayed_refs->lock); |
|
|
|
if (head->must_insert_reserved) { |
|
btrfs_pin_extent(trans, head->bytenr, head->num_bytes, 1); |
|
if (head->is_data) { |
|
struct btrfs_root *csum_root; |
|
|
|
csum_root = btrfs_csum_root(fs_info, head->bytenr); |
|
ret = btrfs_del_csums(trans, csum_root, head->bytenr, |
|
head->num_bytes); |
|
} |
|
} |
|
|
|
btrfs_cleanup_ref_head_accounting(fs_info, delayed_refs, head); |
|
|
|
trace_run_delayed_ref_head(fs_info, head, 0); |
|
btrfs_delayed_ref_unlock(head); |
|
btrfs_put_delayed_ref_head(head); |
|
return ret; |
|
} |
|
|
|
static struct btrfs_delayed_ref_head *btrfs_obtain_ref_head( |
|
struct btrfs_trans_handle *trans) |
|
{ |
|
struct btrfs_delayed_ref_root *delayed_refs = |
|
&trans->transaction->delayed_refs; |
|
struct btrfs_delayed_ref_head *head = NULL; |
|
int ret; |
|
|
|
spin_lock(&delayed_refs->lock); |
|
head = btrfs_select_ref_head(delayed_refs); |
|
if (!head) { |
|
spin_unlock(&delayed_refs->lock); |
|
return head; |
|
} |
|
|
|
/* |
|
* Grab the lock that says we are going to process all the refs for |
|
* this head |
|
*/ |
|
ret = btrfs_delayed_ref_lock(delayed_refs, head); |
|
spin_unlock(&delayed_refs->lock); |
|
|
|
/* |
|
* We may have dropped the spin lock to get the head mutex lock, and |
|
* that might have given someone else time to free the head. If that's |
|
* true, it has been removed from our list and we can move on. |
|
*/ |
|
if (ret == -EAGAIN) |
|
head = ERR_PTR(-EAGAIN); |
|
|
|
return head; |
|
} |
|
|
|
static int btrfs_run_delayed_refs_for_head(struct btrfs_trans_handle *trans, |
|
struct btrfs_delayed_ref_head *locked_ref, |
|
unsigned long *run_refs) |
|
{ |
|
struct btrfs_fs_info *fs_info = trans->fs_info; |
|
struct btrfs_delayed_ref_root *delayed_refs; |
|
struct btrfs_delayed_extent_op *extent_op; |
|
struct btrfs_delayed_ref_node *ref; |
|
int must_insert_reserved = 0; |
|
int ret; |
|
|
|
delayed_refs = &trans->transaction->delayed_refs; |
|
|
|
lockdep_assert_held(&locked_ref->mutex); |
|
lockdep_assert_held(&locked_ref->lock); |
|
|
|
while ((ref = select_delayed_ref(locked_ref))) { |
|
if (ref->seq && |
|
btrfs_check_delayed_seq(fs_info, ref->seq)) { |
|
spin_unlock(&locked_ref->lock); |
|
unselect_delayed_ref_head(delayed_refs, locked_ref); |
|
return -EAGAIN; |
|
} |
|
|
|
(*run_refs)++; |
|
ref->in_tree = 0; |
|
rb_erase_cached(&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); |
|
} |
|
atomic_dec(&delayed_refs->num_entries); |
|
|
|
/* |
|
* 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; |
|
spin_unlock(&locked_ref->lock); |
|
|
|
ret = run_one_delayed_ref(trans, ref, extent_op, |
|
must_insert_reserved); |
|
|
|
btrfs_free_delayed_extent_op(extent_op); |
|
if (ret) { |
|
unselect_delayed_ref_head(delayed_refs, locked_ref); |
|
btrfs_put_delayed_ref(ref); |
|
btrfs_debug(fs_info, "run_one_delayed_ref returned %d", |
|
ret); |
|
return ret; |
|
} |
|
|
|
btrfs_put_delayed_ref(ref); |
|
cond_resched(); |
|
|
|
spin_lock(&locked_ref->lock); |
|
btrfs_merge_delayed_refs(trans, delayed_refs, locked_ref); |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
/* |
|
* Returns 0 on success or if called with an already aborted transaction. |
|
* Returns -ENOMEM or -EIO on failure and will abort the transaction. |
|
*/ |
|
static noinline 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_head *locked_ref = NULL; |
|
ktime_t start = ktime_get(); |
|
int ret; |
|
unsigned long count = 0; |
|
unsigned long actual_count = 0; |
|
|
|
delayed_refs = &trans->transaction->delayed_refs; |
|
do { |
|
if (!locked_ref) { |
|
locked_ref = btrfs_obtain_ref_head(trans); |
|
if (IS_ERR_OR_NULL(locked_ref)) { |
|
if (PTR_ERR(locked_ref) == -EAGAIN) { |
|
continue; |
|
} else { |
|
break; |
|
} |
|
} |
|
count++; |
|
} |
|
/* |
|
* 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()). |
|
*/ |
|
spin_lock(&locked_ref->lock); |
|
btrfs_merge_delayed_refs(trans, delayed_refs, locked_ref); |
|
|
|
ret = btrfs_run_delayed_refs_for_head(trans, locked_ref, |
|
&actual_count); |
|
if (ret < 0 && ret != -EAGAIN) { |
|
/* |
|
* Error, btrfs_run_delayed_refs_for_head already |
|
* unlocked everything so just bail out |
|
*/ |
|
return ret; |
|
} else if (!ret) { |
|
/* |
|
* Success, perform the usual cleanup of a processed |
|
* head |
|
*/ |
|
ret = cleanup_ref_head(trans, locked_ref); |
|
if (ret > 0 ) { |
|
/* We dropped our lock, we need to loop. */ |
|
ret = 0; |
|
continue; |
|
} else if (ret) { |
|
return ret; |
|
} |
|
} |
|
|
|
/* |
|
* Either success case or btrfs_run_delayed_refs_for_head |
|
* returned -EAGAIN, meaning we need to select another head |
|
*/ |
|
|
|
locked_ref = NULL; |
|
cond_resched(); |
|
} while ((nr != -1 && count < nr) || locked_ref); |
|
|
|
/* |
|
* We don't want to include ref heads since we can have empty ref heads |
|
* and those will drastically skew our runtime down since we just do |
|
* accounting, no actual extent tree updates. |
|
*/ |
|
if (actual_count > 0) { |
|
u64 runtime = ktime_to_ns(ktime_sub(ktime_get(), start)); |
|
u64 avg; |
|
|
|
/* |
|
* We weigh the current average higher than our current runtime |
|
* to avoid large swings in the average. |
|
*/ |
|
spin_lock(&delayed_refs->lock); |
|
avg = fs_info->avg_delayed_ref_runtime * 3 + runtime; |
|
fs_info->avg_delayed_ref_runtime = avg >> 2; /* div by 4 */ |
|
spin_unlock(&delayed_refs->lock); |
|
} |
|
return 0; |
|
} |
|
|
|
#ifdef SCRAMBLE_DELAYED_REFS |
|
/* |
|
* Normally delayed refs get processed in ascending bytenr order. This |
|
* correlates in most cases to the order added. To expose dependencies on this |
|
* order, we start to process the tree in the middle instead of the beginning |
|
*/ |
|
static u64 find_middle(struct rb_root *root) |
|
{ |
|
struct rb_node *n = root->rb_node; |
|
struct btrfs_delayed_ref_node *entry; |
|
int alt = 1; |
|
u64 middle; |
|
u64 first = 0, last = 0; |
|
|
|
n = rb_first(root); |
|
if (n) { |
|
entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node); |
|
first = entry->bytenr; |
|
} |
|
n = rb_last(root); |
|
if (n) { |
|
entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node); |
|
last = entry->bytenr; |
|
} |
|
n = root->rb_node; |
|
|
|
while (n) { |
|
entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node); |
|
WARN_ON(!entry->in_tree); |
|
|
|
middle = entry->bytenr; |
|
|
|
if (alt) |
|
n = n->rb_left; |
|
else |
|
n = n->rb_right; |
|
|
|
alt = 1 - alt; |
|
} |
|
return middle; |
|
} |
|
#endif |
|
|
|
/* |
|
* this starts processing the delayed reference count updates and |
|
* extent insertions we have queued up so far. count can be |
|
* 0, which means to process everything in the tree at the start |
|
* of the run (but not newly added entries), or it can be some target |
|
* number you'd like to process. |
|
* |
|
* Returns 0 on success or if called with an aborted transaction |
|
* Returns <0 on error and aborts the transaction |
|
*/ |
|
int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans, |
|
unsigned long count) |
|
{ |
|
struct btrfs_fs_info *fs_info = trans->fs_info; |
|
struct rb_node *node; |
|
struct btrfs_delayed_ref_root *delayed_refs; |
|
struct btrfs_delayed_ref_head *head; |
|
int ret; |
|
int run_all = count == (unsigned long)-1; |
|
|
|
/* We'll clean this up in btrfs_cleanup_transaction */ |
|
if (TRANS_ABORTED(trans)) |
|
return 0; |
|
|
|
if (test_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags)) |
|
return 0; |
|
|
|
delayed_refs = &trans->transaction->delayed_refs; |
|
if (count == 0) |
|
count = delayed_refs->num_heads_ready; |
|
|
|
again: |
|
#ifdef SCRAMBLE_DELAYED_REFS |
|
delayed_refs->run_delayed_start = find_middle(&delayed_refs->root); |
|
#endif |
|
ret = __btrfs_run_delayed_refs(trans, count); |
|
if (ret < 0) { |
|
btrfs_abort_transaction(trans, ret); |
|
return ret; |
|
} |
|
|
|
if (run_all) { |
|
btrfs_create_pending_block_groups(trans); |
|
|
|
spin_lock(&delayed_refs->lock); |
|
node = rb_first_cached(&delayed_refs->href_root); |
|
if (!node) { |
|
spin_unlock(&delayed_refs->lock); |
|
goto out; |
|
} |
|
head = rb_entry(node, struct btrfs_delayed_ref_head, |
|
href_node); |
|
refcount_inc(&head->refs); |
|
spin_unlock(&delayed_refs->lock); |
|
|
|
/* Mutex was contended, block until it's released and retry. */ |
|
mutex_lock(&head->mutex); |
|
mutex_unlock(&head->mutex); |
|
|
|
btrfs_put_delayed_ref_head(head); |
|
cond_resched(); |
|
goto again; |
|
} |
|
out: |
|
return 0; |
|
} |
|
|
|
int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans, |
|
struct extent_buffer *eb, u64 flags, |
|
int level, int is_data) |
|
{ |
|
struct btrfs_delayed_extent_op *extent_op; |
|
int ret; |
|
|
|
extent_op = btrfs_alloc_delayed_extent_op(); |
|
if (!extent_op) |
|
return -ENOMEM; |
|
|
|
extent_op->flags_to_set = flags; |
|
extent_op->update_flags = true; |
|
extent_op->update_key = false; |
|
extent_op->is_data = is_data ? true : false; |
|
extent_op->level = level; |
|
|
|
ret = btrfs_add_delayed_extent_op(trans, eb->start, eb->len, extent_op); |
|
if (ret) |
|
btrfs_free_delayed_extent_op(extent_op); |
|
return ret; |
|
} |
|
|
|
static noinline int check_delayed_ref(struct btrfs_root *root, |
|
struct btrfs_path *path, |
|
u64 objectid, u64 offset, u64 bytenr) |
|
{ |
|
struct btrfs_delayed_ref_head *head; |
|
struct btrfs_delayed_ref_node *ref; |
|
struct btrfs_delayed_data_ref *data_ref; |
|
struct btrfs_delayed_ref_root *delayed_refs; |
|
struct btrfs_transaction *cur_trans; |
|
struct rb_node *node; |
|
int ret = 0; |
|
|
|
spin_lock(&root->fs_info->trans_lock); |
|
cur_trans = root->fs_info->running_transaction; |
|
if (cur_trans) |
|
refcount_inc(&cur_trans->use_count); |
|
spin_unlock(&root->fs_info->trans_lock); |
|
if (!cur_trans) |
|
return 0; |
|
|
|
delayed_refs = &cur_trans->delayed_refs; |
|
spin_lock(&delayed_refs->lock); |
|
head = btrfs_find_delayed_ref_head(delayed_refs, bytenr); |
|
if (!head) { |
|
spin_unlock(&delayed_refs->lock); |
|
btrfs_put_transaction(cur_trans); |
|
return 0; |
|
} |
|
|
|
if (!mutex_trylock(&head->mutex)) { |
|
refcount_inc(&head->refs); |
|
spin_unlock(&delayed_refs->lock); |
|
|
|
btrfs_release_path(path); |
|
|
|
/* |
|
* Mutex was contended, block until it's released and let |
|
* caller try again |
|
*/ |
|
mutex_lock(&head->mutex); |
|
mutex_unlock(&head->mutex); |
|
btrfs_put_delayed_ref_head(head); |
|
btrfs_put_transaction(cur_trans); |
|
return -EAGAIN; |
|
} |
|
spin_unlock(&delayed_refs->lock); |
|
|
|
spin_lock(&head->lock); |
|
/* |
|
* XXX: We should replace this with a proper search function in the |
|
* future. |
|
*/ |
|
for (node = rb_first_cached(&head->ref_tree); node; |
|
node = rb_next(node)) { |
|
ref = rb_entry(node, struct btrfs_delayed_ref_node, ref_node); |
|
/* If it's a shared ref we know a cross reference exists */ |
|
if (ref->type != BTRFS_EXTENT_DATA_REF_KEY) { |
|
ret = 1; |
|
break; |
|
} |
|
|
|
data_ref = btrfs_delayed_node_to_data_ref(ref); |
|
|
|
/* |
|
* If our ref doesn't match the one we're currently looking at |
|
* then we have a cross reference. |
|
*/ |
|
if (data_ref->root != root->root_key.objectid || |
|
data_ref->objectid != objectid || |
|
data_ref->offset != offset) { |
|
ret = 1; |
|
break; |
|
} |
|
} |
|
spin_unlock(&head->lock); |
|
mutex_unlock(&head->mutex); |
|
btrfs_put_transaction(cur_trans); |
|
return ret; |
|
} |
|
|
|
static noinline int check_committed_ref(struct btrfs_root *root, |
|
struct btrfs_path *path, |
|
u64 objectid, u64 offset, u64 bytenr, |
|
bool strict) |
|
{ |
|
struct btrfs_fs_info *fs_info = root->fs_info; |
|
struct btrfs_root *extent_root = btrfs_extent_root(fs_info, bytenr); |
|
struct extent_buffer *leaf; |
|
struct btrfs_extent_data_ref *ref; |
|
struct btrfs_extent_inline_ref *iref; |
|
struct btrfs_extent_item *ei; |
|
struct btrfs_key key; |
|
u32 item_size; |
|
int type; |
|
int ret; |
|
|
|
key.objectid = bytenr; |
|
key.offset = (u64)-1; |
|
key.type = BTRFS_EXTENT_ITEM_KEY; |
|
|
|
ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0); |
|
if (ret < 0) |
|
goto out; |
|
BUG_ON(ret == 0); /* Corruption */ |
|
|
|
ret = -ENOENT; |
|
if (path->slots[0] == 0) |
|
goto out; |
|
|
|
path->slots[0]--; |
|
leaf = path->nodes[0]; |
|
btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); |
|
|
|
if (key.objectid != bytenr || key.type != BTRFS_EXTENT_ITEM_KEY) |
|
goto out; |
|
|
|
ret = 1; |
|
item_size = btrfs_item_size(leaf, path->slots[0]); |
|
ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item); |
|
|
|
/* If extent item has more than 1 inline ref then it's shared */ |
|
if (item_size != sizeof(*ei) + |
|
btrfs_extent_inline_ref_size(BTRFS_EXTENT_DATA_REF_KEY)) |
|
goto out; |
|
|
|
/* |
|
* If extent created before last snapshot => it's shared unless the |
|
* snapshot has been deleted. Use the heuristic if strict is false. |
|
*/ |
|
if (!strict && |
|
(btrfs_extent_generation(leaf, ei) <= |
|
btrfs_root_last_snapshot(&root->root_item))) |
|
goto out; |
|
|
|
iref = (struct btrfs_extent_inline_ref *)(ei + 1); |
|
|
|
/* If this extent has SHARED_DATA_REF then it's shared */ |
|
type = btrfs_get_extent_inline_ref_type(leaf, iref, BTRFS_REF_TYPE_DATA); |
|
if (type != BTRFS_EXTENT_DATA_REF_KEY) |
|
goto out; |
|
|
|
ref = (struct btrfs_extent_data_ref *)(&iref->offset); |
|
if (btrfs_extent_refs(leaf, ei) != |
|
btrfs_extent_data_ref_count(leaf, ref) || |
|
btrfs_extent_data_ref_root(leaf, ref) != |
|
root->root_key.objectid || |
|
btrfs_extent_data_ref_objectid(leaf, ref) != objectid || |
|
btrfs_extent_data_ref_offset(leaf, ref) != offset) |
|
goto out; |
|
|
|
ret = 0; |
|
out: |
|
return ret; |
|
} |
|
|
|
int btrfs_cross_ref_exist(struct btrfs_root *root, u64 objectid, u64 offset, |
|
u64 bytenr, bool strict) |
|
{ |
|
struct btrfs_path *path; |
|
int ret; |
|
|
|
path = btrfs_alloc_path(); |
|
if (!path) |
|
return -ENOMEM; |
|
|
|
do { |
|
ret = check_committed_ref(root, path, objectid, |
|
offset, bytenr, strict); |
|
if (ret && ret != -ENOENT) |
|
goto out; |
|
|
|
ret = check_delayed_ref(root, path, objectid, offset, bytenr); |
|
} while (ret == -EAGAIN); |
|
|
|
out: |
|
btrfs_free_path(path); |
|
if (btrfs_is_data_reloc_root(root)) |
|
WARN_ON(ret > 0); |
|
return ret; |
|
} |
|
|
|
static int __btrfs_mod_ref(struct btrfs_trans_handle *trans, |
|
struct btrfs_root *root, |
|
struct extent_buffer *buf, |
|
int full_backref, int inc) |
|
{ |
|
struct btrfs_fs_info *fs_info = root->fs_info; |
|
u64 bytenr; |
|
u64 num_bytes; |
|
u64 parent; |
|
u64 ref_root; |
|
u32 nritems; |
|
struct btrfs_key key; |
|
struct btrfs_file_extent_item *fi; |
|
struct btrfs_ref generic_ref = { 0 }; |
|
bool for_reloc = btrfs_header_flag(buf, BTRFS_HEADER_FLAG_RELOC); |
|
int i; |
|
int action; |
|
int level; |
|
int ret = 0; |
|
|
|
if (btrfs_is_testing(fs_info)) |
|
return 0; |
|
|
|
ref_root = btrfs_header_owner(buf); |
|
nritems = btrfs_header_nritems(buf); |
|
level = btrfs_header_level(buf); |
|
|
|
if (!test_bit(BTRFS_ROOT_SHAREABLE, &root->state) && level == 0) |
|
return 0; |
|
|
|
if (full_backref) |
|
parent = buf->start; |
|
else |
|
parent = 0; |
|
if (inc) |
|
action = BTRFS_ADD_DELAYED_REF; |
|
else |
|
action = BTRFS_DROP_DELAYED_REF; |
|
|
|
for (i = 0; i < nritems; i++) { |
|
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); |
|
btrfs_init_generic_ref(&generic_ref, action, bytenr, |
|
num_bytes, parent); |
|
btrfs_init_data_ref(&generic_ref, ref_root, key.objectid, |
|
key.offset, root->root_key.objectid, |
|
for_reloc); |
|
if (inc) |
|
ret = btrfs_inc_extent_ref(trans, &generic_ref); |
|
else |
|
ret = btrfs_free_extent(trans, &generic_ref); |
|
if (ret) |
|
goto fail; |
|
} else { |
|
bytenr = btrfs_node_blockptr(buf, i); |
|
num_bytes = fs_info->nodesize; |
|
btrfs_init_generic_ref(&generic_ref, action, bytenr, |
|
num_bytes, parent); |
|
btrfs_init_tree_ref(&generic_ref, level - 1, ref_root, |
|
root->root_key.objectid, for_reloc); |
|
if (inc) |
|
ret = btrfs_inc_extent_ref(trans, &generic_ref); |
|
else |
|
ret = btrfs_free_extent(trans, &generic_ref); |
|
if (ret) |
|
goto fail; |
|
} |
|
} |
|
return 0; |
|
fail: |
|
return ret; |
|
} |
|
|
|
int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
|
struct extent_buffer *buf, int full_backref) |
|
{ |
|
return __btrfs_mod_ref(trans, root, buf, full_backref, 1); |
|
} |
|
|
|
int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
|
struct extent_buffer *buf, int full_backref) |
|
{ |
|
return __btrfs_mod_ref(trans, root, buf, full_backref, 0); |
|
} |
|
|
|
static u64 get_alloc_profile_by_root(struct btrfs_root *root, int data) |
|
{ |
|
struct btrfs_fs_info *fs_info = root->fs_info; |
|
u64 flags; |
|
u64 ret; |
|
|
|
if (data) |
|
flags = BTRFS_BLOCK_GROUP_DATA; |
|
else if (root == fs_info->chunk_root) |
|
flags = BTRFS_BLOCK_GROUP_SYSTEM; |
|
else |
|
flags = BTRFS_BLOCK_GROUP_METADATA; |
|
|
|
ret = btrfs_get_alloc_profile(fs_info, flags); |
|
return ret; |
|
} |
|
|
|
static u64 first_logical_byte(struct btrfs_fs_info *fs_info, u64 search_start) |
|
{ |
|
struct btrfs_block_group *cache; |
|
u64 bytenr; |
|
|
|
spin_lock(&fs_info->block_group_cache_lock); |
|
bytenr = fs_info->first_logical_byte; |
|
spin_unlock(&fs_info->block_group_cache_lock); |
|
|
|
if (bytenr < (u64)-1) |
|
return bytenr; |
|
|
|
cache = btrfs_lookup_first_block_group(fs_info, search_start); |
|
if (!cache) |
|
return 0; |
|
|
|
bytenr = cache->start; |
|
btrfs_put_block_group(cache); |
|
|
|
return bytenr; |
|
} |
|
|
|
static int pin_down_extent(struct btrfs_trans_handle *trans, |
|
struct btrfs_block_group *cache, |
|
u64 bytenr, u64 num_bytes, int reserved) |
|
{ |
|
struct btrfs_fs_info *fs_info = cache->fs_info; |
|
|
|
spin_lock(&cache->space_info->lock); |
|
spin_lock(&cache->lock); |
|
cache->pinned += num_bytes; |
|
btrfs_space_info_update_bytes_pinned(fs_info, cache->space_info, |
|
num_bytes); |
|
if (reserved) { |
|
cache->reserved -= num_bytes; |
|
cache->space_info->bytes_reserved -= num_bytes; |
|
} |
|
spin_unlock(&cache->lock); |
|
spin_unlock(&cache->space_info->lock); |
|
|
|
set_extent_dirty(&trans->transaction->pinned_extents, bytenr, |
|
bytenr + num_bytes - 1, GFP_NOFS | __GFP_NOFAIL); |
|
return 0; |
|
} |
|
|
|
int btrfs_pin_extent(struct btrfs_trans_handle *trans, |
|
u64 bytenr, u64 num_bytes, int reserved) |
|
{ |
|
struct btrfs_block_group *cache; |
|
|
|
cache = btrfs_lookup_block_group(trans->fs_info, bytenr); |
|
BUG_ON(!cache); /* Logic error */ |
|
|
|
pin_down_extent(trans, cache, bytenr, num_bytes, reserved); |
|
|
|
btrfs_put_block_group(cache); |
|
return 0; |
|
} |
|
|
|
/* |
|
* this function must be called within transaction |
|
*/ |
|
int btrfs_pin_extent_for_log_replay(struct btrfs_trans_handle *trans, |
|
u64 bytenr, u64 num_bytes) |
|
{ |
|
struct btrfs_block_group *cache; |
|
int ret; |
|
|
|
cache = btrfs_lookup_block_group(trans->fs_info, bytenr); |
|
if (!cache) |
|
return -EINVAL; |
|
|
|
/* |
|
* pull in the free space cache (if any) so that our pin |
|
* removes the free space from the cache. We have load_only set |
|
* to one because the slow code to read in the free extents does check |
|
* the pinned extents. |
|
*/ |
|
btrfs_cache_block_group(cache, 1); |
|
/* |
|
* Make sure we wait until the cache is completely built in case it is |
|
* missing or is invalid and therefore needs to be rebuilt. |
|
*/ |
|
ret = btrfs_wait_block_group_cache_done(cache); |
|
if (ret) |
|
goto out; |
|
|
|
pin_down_extent(trans, cache, bytenr, num_bytes, 0); |
|
|
|
/* remove us from the free space cache (if we're there at all) */ |
|
ret = btrfs_remove_free_space(cache, bytenr, num_bytes); |
|
out: |
|
btrfs_put_block_group(cache); |
|
return ret; |
|
} |
|
|
|
static int __exclude_logged_extent(struct btrfs_fs_info *fs_info, |
|
u64 start, u64 num_bytes) |
|
{ |
|
int ret; |
|
struct btrfs_block_group *block_group; |
|
|
|
block_group = btrfs_lookup_block_group(fs_info, start); |
|
if (!block_group) |
|
return -EINVAL; |
|
|
|
btrfs_cache_block_group(block_group, 1); |
|
/* |
|
* Make sure we wait until the cache is completely built in case it is |
|
* missing or is invalid and therefore needs to be rebuilt. |
|
*/ |
|
ret = btrfs_wait_block_group_cache_done(block_group); |
|
if (ret) |
|
goto out; |
|
|
|
ret = btrfs_remove_free_space(block_group, start, num_bytes); |
|
out: |
|
btrfs_put_block_group(block_group); |
|
return ret; |
|
} |
|
|
|
int btrfs_exclude_logged_extents(struct extent_buffer *eb) |
|
{ |
|
struct btrfs_fs_info *fs_info = eb->fs_info; |
|
struct btrfs_file_extent_item *item; |
|
struct btrfs_key key; |
|
int found_type; |
|
int i; |
|
int ret = 0; |
|
|
|
if (!btrfs_fs_incompat(fs_info, MIXED_GROUPS)) |
|
return 0; |
|
|
|
for (i = 0; i < btrfs_header_nritems(eb); i++) { |
|
btrfs_item_key_to_cpu(eb, &key, i); |
|
if (key.type != BTRFS_EXTENT_DATA_KEY) |
|
continue; |
|
item = btrfs_item_ptr(eb, i, struct btrfs_file_extent_item); |
|
found_type = btrfs_file_extent_type(eb, item); |
|
if (found_type == BTRFS_FILE_EXTENT_INLINE) |
|
continue; |
|
if (btrfs_file_extent_disk_bytenr(eb, item) == 0) |
|
continue; |
|
key.objectid = btrfs_file_extent_disk_bytenr(eb, item); |
|
key.offset = btrfs_file_extent_disk_num_bytes(eb, item); |
|
ret = __exclude_logged_extent(fs_info, key.objectid, key.offset); |
|
if (ret) |
|
break; |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
static void |
|
btrfs_inc_block_group_reservations(struct btrfs_block_group *bg) |
|
{ |
|
atomic_inc(&bg->reservations); |
|
} |
|
|
|
/* |
|
* Returns the free cluster for the given space info and sets empty_cluster to |
|
* what it should be based on the mount options. |
|
*/ |
|
static struct btrfs_free_cluster * |
|
fetch_cluster_info(struct btrfs_fs_info *fs_info, |
|
struct btrfs_space_info *space_info, u64 *empty_cluster) |
|
{ |
|
struct btrfs_free_cluster *ret = NULL; |
|
|
|
*empty_cluster = 0; |
|
if (btrfs_mixed_space_info(space_info)) |
|
return ret; |
|
|
|
if (space_info->flags & BTRFS_BLOCK_GROUP_METADATA) { |
|
ret = &fs_info->meta_alloc_cluster; |
|
if (btrfs_test_opt(fs_info, SSD)) |
|
*empty_cluster = SZ_2M; |
|
else |
|
*empty_cluster = SZ_64K; |
|
} else if ((space_info->flags & BTRFS_BLOCK_GROUP_DATA) && |
|
btrfs_test_opt(fs_info, SSD_SPREAD)) { |
|
*empty_cluster = SZ_2M; |
|
ret = &fs_info->data_alloc_cluster; |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
static int unpin_extent_range(struct btrfs_fs_info *fs_info, |
|
u64 start, u64 end, |
|
const bool return_free_space) |
|
{ |
|
struct btrfs_block_group *cache = NULL; |
|
struct btrfs_space_info *space_info; |
|
struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv; |
|
struct btrfs_free_cluster *cluster = NULL; |
|
u64 len; |
|
u64 total_unpinned = 0; |
|
u64 empty_cluster = 0; |
|
bool readonly; |
|
|
|
while (start <= end) { |
|
readonly = false; |
|
if (!cache || |
|
start >= cache->start + cache->length) { |
|
if (cache) |
|
btrfs_put_block_group(cache); |
|
total_unpinned = 0; |
|
cache = btrfs_lookup_block_group(fs_info, start); |
|
BUG_ON(!cache); /* Logic error */ |
|
|
|
cluster = fetch_cluster_info(fs_info, |
|
cache->space_info, |
|
&empty_cluster); |
|
empty_cluster <<= 1; |
|
} |
|
|
|
len = cache->start + cache->length - start; |
|
len = min(len, end + 1 - start); |
|
|
|
down_read(&fs_info->commit_root_sem); |
|
if (start < cache->last_byte_to_unpin && return_free_space) { |
|
u64 add_len = min(len, cache->last_byte_to_unpin - start); |
|
|
|
btrfs_add_free_space(cache, start, add_len); |
|
} |
|
up_read(&fs_info->commit_root_sem); |
|
|
|
start += len; |
|
total_unpinned += len; |
|
space_info = cache->space_info; |
|
|
|
/* |
|
* If this space cluster has been marked as fragmented and we've |
|
* unpinned enough in this block group to potentially allow a |
|
* cluster to be created inside of it go ahead and clear the |
|
* fragmented check. |
|
*/ |
|
if (cluster && cluster->fragmented && |
|
total_unpinned > empty_cluster) { |
|
spin_lock(&cluster->lock); |
|
cluster->fragmented = 0; |
|
spin_unlock(&cluster->lock); |
|
} |
|
|
|
spin_lock(&space_info->lock); |
|
spin_lock(&cache->lock); |
|
cache->pinned -= len; |
|
btrfs_space_info_update_bytes_pinned(fs_info, space_info, -len); |
|
space_info->max_extent_size = 0; |
|
if (cache->ro) { |
|
space_info->bytes_readonly += len; |
|
readonly = true; |
|
} else if (btrfs_is_zoned(fs_info)) { |
|
/* Need reset before reusing in a zoned block group */ |
|
space_info->bytes_zone_unusable += len; |
|
readonly = true; |
|
} |
|
spin_unlock(&cache->lock); |
|
if (!readonly && return_free_space && |
|
global_rsv->space_info == space_info) { |
|
u64 to_add = len; |
|
|
|
spin_lock(&global_rsv->lock); |
|
if (!global_rsv->full) { |
|
to_add = min(len, global_rsv->size - |
|
global_rsv->reserved); |
|
global_rsv->reserved += to_add; |
|
btrfs_space_info_update_bytes_may_use(fs_info, |
|
space_info, to_add); |
|
if (global_rsv->reserved >= global_rsv->size) |
|
global_rsv->full = 1; |
|
len -= to_add; |
|
} |
|
spin_unlock(&global_rsv->lock); |
|
} |
|
/* Add to any tickets we may have */ |
|
if (!readonly && return_free_space && len) |
|
btrfs_try_granting_tickets(fs_info, space_info); |
|
spin_unlock(&space_info->lock); |
|
} |
|
|
|
if (cache) |
|
btrfs_put_block_group(cache); |
|
return 0; |
|
} |
|
|
|
int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans) |
|
{ |
|
struct btrfs_fs_info *fs_info = trans->fs_info; |
|
struct btrfs_block_group *block_group, *tmp; |
|
struct list_head *deleted_bgs; |
|
struct extent_io_tree *unpin; |
|
u64 start; |
|
u64 end; |
|
int ret; |
|
|
|
unpin = &trans->transaction->pinned_extents; |
|
|
|
while (!TRANS_ABORTED(trans)) { |
|
struct extent_state *cached_state = NULL; |
|
|
|
mutex_lock(&fs_info->unused_bg_unpin_mutex); |
|
ret = find_first_extent_bit(unpin, 0, &start, &end, |
|
EXTENT_DIRTY, &cached_state); |
|
if (ret) { |
|
mutex_unlock(&fs_info->unused_bg_unpin_mutex); |
|
break; |
|
} |
|
|
|
if (btrfs_test_opt(fs_info, DISCARD_SYNC)) |
|
ret = btrfs_discard_extent(fs_info, start, |
|
end + 1 - start, NULL); |
|
|
|
clear_extent_dirty(unpin, start, end, &cached_state); |
|
unpin_extent_range(fs_info, start, end, true); |
|
mutex_unlock(&fs_info->unused_bg_unpin_mutex); |
|
free_extent_state(cached_state); |
|
cond_resched(); |
|
} |
|
|
|
if (btrfs_test_opt(fs_info, DISCARD_ASYNC)) { |
|
btrfs_discard_calc_delay(&fs_info->discard_ctl); |
|
btrfs_discard_schedule_work(&fs_info->discard_ctl, true); |
|
} |
|
|
|
/* |
|
* Transaction is finished. We don't need the lock anymore. We |
|
* do need to clean up the block groups in case of a transaction |
|
* abort. |
|
*/ |
|
deleted_bgs = &trans->transaction->deleted_bgs; |
|
list_for_each_entry_safe(block_group, tmp, deleted_bgs, bg_list) { |
|
u64 trimmed = 0; |
|
|
|
ret = -EROFS; |
|
if (!TRANS_ABORTED(trans)) |
|
ret = btrfs_discard_extent(fs_info, |
|
block_group->start, |
|
block_group->length, |
|
&trimmed); |
|
|
|
list_del_init(&block_group->bg_list); |
|
btrfs_unfreeze_block_group(block_group); |
|
btrfs_put_block_group(block_group); |
|
|
|
if (ret) { |
|
const char *errstr = btrfs_decode_error(ret); |
|
btrfs_warn(fs_info, |
|
"discard failed while removing blockgroup: errno=%d %s", |
|
ret, errstr); |
|
} |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
/* |
|
* Drop one or more refs of @node. |
|
* |
|
* 1. Locate the extent refs. |
|
* It's either inline in EXTENT/METADATA_ITEM or in keyed SHARED_* item. |
|
* Locate it, then reduce the refs number or remove the ref line completely. |
|
* |
|
* 2. Update the refs count in EXTENT/METADATA_ITEM |
|
* |
|
* Inline backref case: |
|
* |
|
* in extent tree we have: |
|
* |
|
* item 0 key (13631488 EXTENT_ITEM 1048576) itemoff 16201 itemsize 82 |
|
* refs 2 gen 6 flags DATA |
|
* extent data backref root FS_TREE objectid 258 offset 0 count 1 |
|
* extent data backref root FS_TREE objectid 257 offset 0 count 1 |
|
* |
|
* This function gets called with: |
|
* |
|
* node->bytenr = 13631488 |
|
* node->num_bytes = 1048576 |
|
* root_objectid = FS_TREE |
|
* owner_objectid = 257 |
|
* owner_offset = 0 |
|
* refs_to_drop = 1 |
|
* |
|
* Then we should get some like: |
|
* |
|
* item 0 key (13631488 EXTENT_ITEM 1048576) itemoff 16201 itemsize 82 |
|
* refs 1 gen 6 flags DATA |
|
* extent data backref root FS_TREE objectid 258 offset 0 count 1 |
|
* |
|
* Keyed backref case: |
|
* |
|
* in extent tree we have: |
|
* |
|
* item 0 key (13631488 EXTENT_ITEM 1048576) itemoff 3971 itemsize 24 |
|
* refs 754 gen 6 flags DATA |
|
* [...] |
|
* item 2 key (13631488 EXTENT_DATA_REF <HASH>) itemoff 3915 itemsize 28 |
|
* extent data backref root FS_TREE objectid 866 offset 0 count 1 |
|
* |
|
* This function get called with: |
|
* |
|
* node->bytenr = 13631488 |
|
* node->num_bytes = 1048576 |
|
* root_objectid = FS_TREE |
|
* owner_objectid = 866 |
|
* owner_offset = 0 |
|
* refs_to_drop = 1 |
|
* |
|
* Then we should get some like: |
|
* |
|
* item 0 key (13631488 EXTENT_ITEM 1048576) itemoff 3971 itemsize 24 |
|
* refs 753 gen 6 flags DATA |
|
* |
|
* And that (13631488 EXTENT_DATA_REF <HASH>) gets removed. |
|
*/ |
|
static int __btrfs_free_extent(struct btrfs_trans_handle *trans, |
|
struct btrfs_delayed_ref_node *node, u64 parent, |
|
u64 root_objectid, u64 owner_objectid, |
|
u64 owner_offset, int refs_to_drop, |
|
struct btrfs_delayed_extent_op *extent_op) |
|
{ |
|
struct btrfs_fs_info *info = trans->fs_info; |
|
struct btrfs_key key; |
|
struct btrfs_path *path; |
|
struct btrfs_root *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; |
|
u64 bytenr = node->bytenr; |
|
u64 num_bytes = node->num_bytes; |
|
int last_ref = 0; |
|
bool skinny_metadata = btrfs_fs_incompat(info, SKINNY_METADATA); |
|
|
|
extent_root = btrfs_extent_root(info, bytenr); |
|
ASSERT(extent_root); |
|
|
|
path = btrfs_alloc_path(); |
|
if (!path) |
|
return -ENOMEM; |
|
|
|
is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID; |
|
|
|
if (!is_data && refs_to_drop != 1) { |
|
btrfs_crit(info, |
|
"invalid refs_to_drop, dropping more than 1 refs for tree block %llu refs_to_drop %u", |
|
node->bytenr, refs_to_drop); |
|
ret = -EINVAL; |
|
btrfs_abort_transaction(trans, ret); |
|
goto out; |
|
} |
|
|
|
if (is_data) |
|
skinny_metadata = false; |
|
|
|
ret = lookup_extent_backref(trans, path, &iref, bytenr, num_bytes, |
|
parent, root_objectid, owner_objectid, |
|
owner_offset); |
|
if (ret == 0) { |
|
/* |
|
* Either the inline backref or the SHARED_DATA_REF/ |
|
* SHARED_BLOCK_REF is found |
|
* |
|
* Here is a quick path to locate EXTENT/METADATA_ITEM. |
|
* It's possible the EXTENT/METADATA_ITEM is near current slot. |
|
*/ |
|
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; |
|
} |
|
|
|
/* Quick path didn't find the EXTEMT/METADATA_ITEM */ |
|
if (path->slots[0] - extent_slot > 5) |
|
break; |
|
extent_slot--; |
|
} |
|
|
|
if (!found_extent) { |
|
if (iref) { |
|
btrfs_crit(info, |
|
"invalid iref, no EXTENT/METADATA_ITEM found but has inline extent ref"); |
|
btrfs_abort_transaction(trans, -EUCLEAN); |
|
goto err_dump; |
|
} |
|
/* Must be SHARED_* item, remove the backref first */ |
|
ret = remove_extent_backref(trans, extent_root, path, |
|
NULL, refs_to_drop, is_data, |
|
&last_ref); |
|
if (ret) { |
|
btrfs_abort_transaction(trans, ret); |
|
goto out; |
|
} |
|
btrfs_release_path(path); |
|
|
|
/* Slow path to locate EXTENT/METADATA_ITEM */ |
|
key.objectid = bytenr; |
|
key.type = BTRFS_EXTENT_ITEM_KEY; |
|
key.offset = num_bytes; |
|
|
|
if (!is_data && skinny_metadata) { |
|
key.type = BTRFS_METADATA_ITEM_KEY; |
|
key.offset = owner_objectid; |
|
} |
|
|
|
ret = btrfs_search_slot(trans, extent_root, |
|
&key, path, -1, 1); |
|
if (ret > 0 && skinny_metadata && path->slots[0]) { |
|
/* |
|
* Couldn't find our skinny metadata item, |
|
* see if we have ye olde extent item. |
|
*/ |
|
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 = false; |
|
key.objectid = bytenr; |
|
key.type = BTRFS_EXTENT_ITEM_KEY; |
|
key.offset = num_bytes; |
|
btrfs_release_path(path); |
|
ret = btrfs_search_slot(trans, extent_root, |
|
&key, path, -1, 1); |
|
} |
|
|
|
if (ret) { |
|
btrfs_err(info, |
|
"umm, got %d back from search, was looking for %llu", |
|
ret, bytenr); |
|
if (ret > 0) |
|
btrfs_print_leaf(path->nodes[0]); |
|
} |
|
if (ret < 0) { |
|
btrfs_abort_transaction(trans, ret); |
|
goto out; |
|
} |
|
extent_slot = path->slots[0]; |
|
} |
|
} else if (WARN_ON(ret == -ENOENT)) { |
|
btrfs_print_leaf(path->nodes[0]); |
|
btrfs_err(info, |
|
"unable to find ref byte nr %llu parent %llu root %llu owner %llu offset %llu", |
|
bytenr, parent, root_objectid, owner_objectid, |
|
owner_offset); |
|
btrfs_abort_transaction(trans, ret); |
|
goto out; |
|
} else { |
|
btrfs_abort_transaction(trans, ret); |
|
goto out; |
|
} |
|
|
|
leaf = path->nodes[0]; |
|
item_size = btrfs_item_size(leaf, extent_slot); |
|
if (unlikely(item_size < sizeof(*ei))) { |
|
ret = -EINVAL; |
|
btrfs_print_v0_err(info); |
|
btrfs_abort_transaction(trans, ret); |
|
goto out; |
|
} |
|
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; |
|
if (item_size < sizeof(*ei) + sizeof(*bi)) { |
|
btrfs_crit(info, |
|
"invalid extent item size for key (%llu, %u, %llu) owner %llu, has %u expect >= %zu", |
|
key.objectid, key.type, key.offset, |
|
owner_objectid, item_size, |
|
sizeof(*ei) + sizeof(*bi)); |
|
btrfs_abort_transaction(trans, -EUCLEAN); |
|
goto err_dump; |
|
} |
|
bi = (struct btrfs_tree_block_info *)(ei + 1); |
|
WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi)); |
|
} |
|
|
|
refs = btrfs_extent_refs(leaf, ei); |
|
if (refs < refs_to_drop) { |
|
btrfs_crit(info, |
|
"trying to drop %d refs but we only have %llu for bytenr %llu", |
|
refs_to_drop, refs, bytenr); |
|
btrfs_abort_transaction(trans, -EUCLEAN); |
|
goto err_dump; |
|
} |
|
refs -= refs_to_drop; |
|
|
|
if (refs > 0) { |
|
if (extent_op) |
|
__run_delayed_extent_op(extent_op, leaf, ei); |
|
/* |
|
* In the case of inline back ref, reference count will |
|
* be updated by remove_extent_backref |
|
*/ |
|
if (iref) { |
|
if (!found_extent) { |
|
btrfs_crit(info, |
|
"invalid iref, got inlined extent ref but no EXTENT/METADATA_ITEM found"); |
|
btrfs_abort_transaction(trans, -EUCLEAN); |
|
goto err_dump; |
|
} |
|
} 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, |
|
&last_ref); |
|
if (ret) { |
|
btrfs_abort_transaction(trans, ret); |
|
goto out; |
|
} |
|
} |
|
} else { |
|
/* In this branch refs == 1 */ |
|
if (found_extent) { |
|
if (is_data && refs_to_drop != |
|
extent_data_ref_count(path, iref)) { |
|
btrfs_crit(info, |
|
"invalid refs_to_drop, current refs %u refs_to_drop %u", |
|
extent_data_ref_count(path, iref), |
|
refs_to_drop); |
|
btrfs_abort_transaction(trans, -EUCLEAN); |
|
goto err_dump; |
|
} |
|
if (iref) { |
|
if (path->slots[0] != extent_slot) { |
|
btrfs_crit(info, |
|
"invalid iref, extent item key (%llu %u %llu) doesn't have wanted iref", |
|
key.objectid, key.type, |
|
key.offset); |
|
btrfs_abort_transaction(trans, -EUCLEAN); |
|
goto err_dump; |
|
} |
|
} else { |
|
/* |
|
* No inline ref, we must be at SHARED_* item, |
|
* And it's single ref, it must be: |
|
* | extent_slot ||extent_slot + 1| |
|
* [ EXTENT/METADATA_ITEM ][ SHARED_* ITEM ] |
|
*/ |
|
if (path->slots[0] != extent_slot + 1) { |
|
btrfs_crit(info, |
|
"invalid SHARED_* item, previous item is not EXTENT/METADATA_ITEM"); |
|
btrfs_abort_transaction(trans, -EUCLEAN); |
|
goto err_dump; |
|
} |
|
path->slots[0] = extent_slot; |
|
num_to_del = 2; |
|
} |
|
} |
|
|
|
last_ref = 1; |
|
ret = btrfs_del_items(trans, extent_root, path, path->slots[0], |
|
num_to_del); |
|
if (ret) { |
|
btrfs_abort_transaction(trans, ret); |
|
goto out; |
|
} |
|
btrfs_release_path(path); |
|
|
|
if (is_data) { |
|
struct btrfs_root *csum_root; |
|
csum_root = btrfs_csum_root(info, bytenr); |
|
ret = btrfs_del_csums(trans, csum_root, bytenr, |
|
num_bytes); |
|
if (ret) { |
|
btrfs_abort_transaction(trans, ret); |
|
goto out; |
|
} |
|
} |
|
|
|
ret = add_to_free_space_tree(trans, bytenr, num_bytes); |
|
if (ret) { |
|
btrfs_abort_transaction(trans, ret); |
|
goto out; |
|
} |
|
|
|
ret = btrfs_update_block_group(trans, bytenr, num_bytes, false); |
|
if (ret) { |
|
btrfs_abort_transaction(trans, ret); |
|
goto out; |
|
} |
|
} |
|
btrfs_release_path(path); |
|
|
|
out: |
|
btrfs_free_path(path); |
|
return ret; |
|
err_dump: |
|
/* |
|
* Leaf dump can take up a lot of log buffer, so we only do full leaf |
|
* dump for debug build. |
|
*/ |
|
if (IS_ENABLED(CONFIG_BTRFS_DEBUG)) { |
|
btrfs_crit(info, "path->slots[0]=%d extent_slot=%d", |
|
path->slots[0], extent_slot); |
|
btrfs_print_leaf(path->nodes[0]); |
|
} |
|
|
|
btrfs_free_path(path); |
|
return -EUCLEAN; |
|
} |
|
|
|
/* |
|
* when we free an block, it is possible (and likely) that we free the last |
|
* delayed ref for that extent as well. This searches the delayed ref tree for |
|
* a given extent, and if there are no other delayed refs to be processed, it |
|
* removes it from the tree. |
|
*/ |
|
static noinline int check_ref_cleanup(struct btrfs_trans_handle *trans, |
|
u64 bytenr) |
|
{ |
|
struct btrfs_delayed_ref_head *head; |
|
struct btrfs_delayed_ref_root *delayed_refs; |
|
int ret = 0; |
|
|
|
delayed_refs = &trans->transaction->delayed_refs; |
|
spin_lock(&delayed_refs->lock); |
|
head = btrfs_find_delayed_ref_head(delayed_refs, bytenr); |
|
if (!head) |
|
goto out_delayed_unlock; |
|
|
|
spin_lock(&head->lock); |
|
if (!RB_EMPTY_ROOT(&head->ref_tree.rb_root)) |
|
goto out; |
|
|
|
if (cleanup_extent_op(head) != NULL) |
|
goto out; |
|
|
|
/* |
|
* waiting for the lock here would deadlock. If someone else has it |
|
* locked they are already in the process of dropping it anyway |
|
*/ |
|
if (!mutex_trylock(&head->mutex)) |
|
goto out; |
|
|
|
btrfs_delete_ref_head(delayed_refs, head); |
|
head->processing = 0; |
|
|
|
spin_unlock(&head->lock); |
|
spin_unlock(&delayed_refs->lock); |
|
|
|
BUG_ON(head->extent_op); |
|
if (head->must_insert_reserved) |
|
ret = 1; |
|
|
|
btrfs_cleanup_ref_head_accounting(trans->fs_info, delayed_refs, head); |
|
mutex_unlock(&head->mutex); |
|
btrfs_put_delayed_ref_head(head); |
|
return ret; |
|
out: |
|
spin_unlock(&head->lock); |
|
|
|
out_delayed_unlock: |
|
spin_unlock(&delayed_refs->lock); |
|
return 0; |
|
} |
|
|
|
void btrfs_free_tree_block(struct btrfs_trans_handle *trans, |
|
u64 root_id, |
|
struct extent_buffer *buf, |
|
u64 parent, int last_ref) |
|
{ |
|
struct btrfs_fs_info *fs_info = trans->fs_info; |
|
struct btrfs_ref generic_ref = { 0 }; |
|
int ret; |
|
|
|
btrfs_init_generic_ref(&generic_ref, BTRFS_DROP_DELAYED_REF, |
|
buf->start, buf->len, parent); |
|
btrfs_init_tree_ref(&generic_ref, btrfs_header_level(buf), |
|
root_id, 0, false); |
|
|
|
if (root_id != BTRFS_TREE_LOG_OBJECTID) { |
|
btrfs_ref_tree_mod(fs_info, &generic_ref); |
|
ret = btrfs_add_delayed_tree_ref(trans, &generic_ref, NULL); |
|
BUG_ON(ret); /* -ENOMEM */ |
|
} |
|
|
|
if (last_ref && btrfs_header_generation(buf) == trans->transid) { |
|
struct btrfs_block_group *cache; |
|
bool must_pin = false; |
|
|
|
if (root_id != BTRFS_TREE_LOG_OBJECTID) { |
|
ret = check_ref_cleanup(trans, buf->start); |
|
if (!ret) { |
|
btrfs_redirty_list_add(trans->transaction, buf); |
|
goto out; |
|
} |
|
} |
|
|
|
cache = btrfs_lookup_block_group(fs_info, buf->start); |
|
|
|
if (btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) { |
|
pin_down_extent(trans, cache, buf->start, buf->len, 1); |
|
btrfs_put_block_group(cache); |
|
goto out; |
|
} |
|
|
|
/* |
|
* If this is a leaf and there are tree mod log users, we may |
|
* have recorded mod log operations that point to this leaf. |
|
* So we must make sure no one reuses this leaf's extent before |
|
* mod log operations are applied to a node, otherwise after |
|
* rewinding a node using the mod log operations we get an |
|
* inconsistent btree, as the leaf's extent may now be used as |
|
* a node or leaf for another different btree. |
|
* We are safe from races here because at this point no other |
|
* node or root points to this extent buffer, so if after this |
|
* check a new tree mod log user joins, it will not be able to |
|
* find a node pointing to this leaf and record operations that |
|
* point to this leaf. |
|
*/ |
|
if (btrfs_header_level(buf) == 0 && |
|
test_bit(BTRFS_FS_TREE_MOD_LOG_USERS, &fs_info->flags)) |
|
must_pin = true; |
|
|
|
if (must_pin || btrfs_is_zoned(fs_info)) { |
|
btrfs_redirty_list_add(trans->transaction, buf); |
|
pin_down_extent(trans, cache, buf->start, buf->len, 1); |
|
btrfs_put_block_group(cache); |
|
goto out; |
|
} |
|
|
|
WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)); |
|
|
|
btrfs_add_free_space(cache, buf->start, buf->len); |
|
btrfs_free_reserved_bytes(cache, buf->len, 0); |
|
btrfs_put_block_group(cache); |
|
trace_btrfs_reserved_extent_free(fs_info, buf->start, buf->len); |
|
} |
|
out: |
|
if (last_ref) { |
|
/* |
|
* Deleting the buffer, clear the corrupt flag since it doesn't |
|
* matter anymore. |
|
*/ |
|
clear_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags); |
|
} |
|
} |
|
|
|
/* Can return -ENOMEM */ |
|
int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_ref *ref) |
|
{ |
|
struct btrfs_fs_info *fs_info = trans->fs_info; |
|
int ret; |
|
|
|
if (btrfs_is_testing(fs_info)) |
|
return 0; |
|
|
|
/* |
|
* tree log blocks never actually go into the extent allocation |
|
* tree, just update pinning info and exit early. |
|
*/ |
|
if ((ref->type == BTRFS_REF_METADATA && |
|
ref->tree_ref.owning_root == BTRFS_TREE_LOG_OBJECTID) || |
|
(ref->type == BTRFS_REF_DATA && |
|
ref->data_ref.owning_root == BTRFS_TREE_LOG_OBJECTID)) { |
|
/* unlocks the pinned mutex */ |
|
btrfs_pin_extent(trans, ref->bytenr, ref->len, 1); |
|
ret = 0; |
|
} else if (ref->type == BTRFS_REF_METADATA) { |
|
ret = btrfs_add_delayed_tree_ref(trans, ref, NULL); |
|
} else { |
|
ret = btrfs_add_delayed_data_ref(trans, ref, 0); |
|
} |
|
|
|
if (!((ref->type == BTRFS_REF_METADATA && |
|
ref->tree_ref.owning_root == BTRFS_TREE_LOG_OBJECTID) || |
|
(ref->type == BTRFS_REF_DATA && |
|
ref->data_ref.owning_root == BTRFS_TREE_LOG_OBJECTID))) |
|
btrfs_ref_tree_mod(fs_info, ref); |
|
|
|
return ret; |
|
} |
|
|
|
enum btrfs_loop_type { |
|
LOOP_CACHING_NOWAIT, |
|
LOOP_CACHING_WAIT, |
|
LOOP_ALLOC_CHUNK, |
|
LOOP_NO_EMPTY_SIZE, |
|
}; |
|
|
|
static inline void |
|
btrfs_lock_block_group(struct btrfs_block_group *cache, |
|
int delalloc) |
|
{ |
|
if (delalloc) |
|
down_read(&cache->data_rwsem); |
|
} |
|
|
|
static inline void btrfs_grab_block_group(struct btrfs_block_group *cache, |
|
int delalloc) |
|
{ |
|
btrfs_get_block_group(cache); |
|
if (delalloc) |
|
down_read(&cache->data_rwsem); |
|
} |
|
|
|
static struct btrfs_block_group *btrfs_lock_cluster( |
|
struct btrfs_block_group *block_group, |
|
struct btrfs_free_cluster *cluster, |
|
int delalloc) |
|
__acquires(&cluster->refill_lock) |
|
{ |
|
struct btrfs_block_group *used_bg = NULL; |
|
|
|
spin_lock(&cluster->refill_lock); |
|
while (1) { |
|
used_bg = cluster->block_group; |
|
if (!used_bg) |
|
return NULL; |
|
|
|
if (used_bg == block_group) |
|
return used_bg; |
|
|
|
btrfs_get_block_group(used_bg); |
|
|
|
if (!delalloc) |
|
return used_bg; |
|
|
|
if (down_read_trylock(&used_bg->data_rwsem)) |
|
return used_bg; |
|
|
|
spin_unlock(&cluster->refill_lock); |
|
|
|
/* We should only have one-level nested. */ |
|
down_read_nested(&used_bg->data_rwsem, SINGLE_DEPTH_NESTING); |
|
|
|
spin_lock(&cluster->refill_lock); |
|
if (used_bg == cluster->block_group) |
|
return used_bg; |
|
|
|
up_read(&used_bg->data_rwsem); |
|
btrfs_put_block_group(used_bg); |
|
} |
|
} |
|
|
|
static inline void |
|
btrfs_release_block_group(struct btrfs_block_group *cache, |
|
int delalloc) |
|
{ |
|
if (delalloc) |
|
up_read(&cache->data_rwsem); |
|
btrfs_put_block_group(cache); |
|
} |
|
|
|
enum btrfs_extent_allocation_policy { |
|
BTRFS_EXTENT_ALLOC_CLUSTERED, |
|
BTRFS_EXTENT_ALLOC_ZONED, |
|
}; |
|
|
|
/* |
|
* Structure used internally for find_free_extent() function. Wraps needed |
|
* parameters. |
|
*/ |
|
struct find_free_extent_ctl { |
|
/* Basic allocation info */ |
|
u64 ram_bytes; |
|
u64 num_bytes; |
|
u64 min_alloc_size; |
|
u64 empty_size; |
|
u64 flags; |
|
int delalloc; |
|
|
|
/* Where to start the search inside the bg */ |
|
u64 search_start; |
|
|
|
/* For clustered allocation */ |
|
u64 empty_cluster; |
|
struct btrfs_free_cluster *last_ptr; |
|
bool use_cluster; |
|
|
|
bool have_caching_bg; |
|
bool orig_have_caching_bg; |
|
|
|
/* Allocation is called for tree-log */ |
|
bool for_treelog; |
|
|
|
/* Allocation is called for data relocation */ |
|
bool for_data_reloc; |
|
|
|
/* RAID index, converted from flags */ |
|
int index; |
|
|
|
/* |
|
* Current loop number, check find_free_extent_update_loop() for details |
|
*/ |
|
int loop; |
|
|
|
/* |
|
* Whether we're refilling a cluster, if true we need to re-search |
|
* current block group but don't try to refill the cluster again. |
|
*/ |
|
bool retry_clustered; |
|
|
|
/* |
|
* Whether we're updating free space cache, if true we need to re-search |
|
* current block group but don't try updating free space cache again. |
|
*/ |
|
bool retry_unclustered; |
|
|
|
/* If current block group is cached */ |
|
int cached; |
|
|
|
/* Max contiguous hole found */ |
|
u64 max_extent_size; |
|
|
|
/* Total free space from free space cache, not always contiguous */ |
|
u64 total_free_space; |
|
|
|
/* Found result */ |
|
u64 found_offset; |
|
|
|
/* Hint where to start looking for an empty space */ |
|
u64 hint_byte; |
|
|
|
/* Allocation policy */ |
|
enum btrfs_extent_allocation_policy policy; |
|
}; |
|
|
|
|
|
/* |
|
* Helper function for find_free_extent(). |
|
* |
|
* Return -ENOENT to inform caller that we need fallback to unclustered mode. |
|
* Return -EAGAIN to inform caller that we need to re-search this block group |
|
* Return >0 to inform caller that we find nothing |
|
* Return 0 means we have found a location and set ffe_ctl->found_offset. |
|
*/ |
|
static int find_free_extent_clustered(struct btrfs_block_group *bg, |
|
struct find_free_extent_ctl *ffe_ctl, |
|
struct btrfs_block_group **cluster_bg_ret) |
|
{ |
|
struct btrfs_block_group *cluster_bg; |
|
struct btrfs_free_cluster *last_ptr = ffe_ctl->last_ptr; |
|
u64 aligned_cluster; |
|
u64 offset; |
|
int ret; |
|
|
|
cluster_bg = btrfs_lock_cluster(bg, last_ptr, ffe_ctl->delalloc); |
|
if (!cluster_bg) |
|
goto refill_cluster; |
|
if (cluster_bg != bg && (cluster_bg->ro || |
|
!block_group_bits(cluster_bg, ffe_ctl->flags))) |
|
goto release_cluster; |
|
|
|
offset = btrfs_alloc_from_cluster(cluster_bg, last_ptr, |
|
ffe_ctl->num_bytes, cluster_bg->start, |
|
&ffe_ctl->max_extent_size); |
|
if (offset) { |
|
/* We have a block, we're done */ |
|
spin_unlock(&last_ptr->refill_lock); |
|
trace_btrfs_reserve_extent_cluster(cluster_bg, |
|
ffe_ctl->search_start, ffe_ctl->num_bytes); |
|
*cluster_bg_ret = cluster_bg; |
|
ffe_ctl->found_offset = offset; |
|
return 0; |
|
} |
|
WARN_ON(last_ptr->block_group != cluster_bg); |
|
|
|
release_cluster: |
|
/* |
|
* If we are on LOOP_NO_EMPTY_SIZE, we can't set up a new clusters, so |
|
* lets just skip it and let the allocator find whatever block it can |
|
* find. If we reach this point, we will have tried the cluster |
|
* allocator plenty of times and not have found anything, so we are |
|
* likely way too fragmented for the clustering stuff to find anything. |
|
* |
|
* However, if the cluster is taken from the current block group, |
|
* release the cluster first, so that we stand a better chance of |
|
* succeeding in the unclustered allocation. |
|
*/ |
|
if (ffe_ctl->loop >= LOOP_NO_EMPTY_SIZE && cluster_bg != bg) { |
|
spin_unlock(&last_ptr->refill_lock); |
|
btrfs_release_block_group(cluster_bg, ffe_ctl->delalloc); |
|
return -ENOENT; |
|
} |
|
|
|
/* This cluster didn't work out, free it and start over */ |
|
btrfs_return_cluster_to_free_space(NULL, last_ptr); |
|
|
|
if (cluster_bg != bg) |
|
btrfs_release_block_group(cluster_bg, ffe_ctl->delalloc); |
|
|
|
refill_cluster: |
|
if (ffe_ctl->loop >= LOOP_NO_EMPTY_SIZE) { |
|
spin_unlock(&last_ptr->refill_lock); |
|
return -ENOENT; |
|
} |
|
|
|
aligned_cluster = max_t(u64, |
|
ffe_ctl->empty_cluster + ffe_ctl->empty_size, |
|
bg->full_stripe_len); |
|
ret = btrfs_find_space_cluster(bg, last_ptr, ffe_ctl->search_start, |
|
ffe_ctl->num_bytes, aligned_cluster); |
|
if (ret == 0) { |
|
/* Now pull our allocation out of this cluster */ |
|
offset = btrfs_alloc_from_cluster(bg, last_ptr, |
|
ffe_ctl->num_bytes, ffe_ctl->search_start, |
|
&ffe_ctl->max_extent_size); |
|
if (offset) { |
|
/* We found one, proceed */ |
|
spin_unlock(&last_ptr->refill_lock); |
|
trace_btrfs_reserve_extent_cluster(bg, |
|
ffe_ctl->search_start, |
|
ffe_ctl->num_bytes); |
|
ffe_ctl->found_offset = offset; |
|
return 0; |
|
} |
|
} else if (!ffe_ctl->cached && ffe_ctl->loop > LOOP_CACHING_NOWAIT && |
|
!ffe_ctl->retry_clustered) { |
|
spin_unlock(&last_ptr->refill_lock); |
|
|
|
ffe_ctl->retry_clustered = true; |
|
btrfs_wait_block_group_cache_progress(bg, ffe_ctl->num_bytes + |
|
ffe_ctl->empty_cluster + ffe_ctl->empty_size); |
|
return -EAGAIN; |
|
} |
|
/* |
|
* At this point we either didn't find a cluster or we weren't able to |
|
* allocate a block from our cluster. Free the cluster we've been |
|
* trying to use, and go to the next block group. |
|
*/ |
|
btrfs_return_cluster_to_free_space(NULL, last_ptr); |
|
spin_unlock(&last_ptr->refill_lock); |
|
return 1; |
|
} |
|
|
|
/* |
|
* Return >0 to inform caller that we find nothing |
|
* Return 0 when we found an free extent and set ffe_ctrl->found_offset |
|
* Return -EAGAIN to inform caller that we need to re-search this block group |
|
*/ |
|
static int find_free_extent_unclustered(struct btrfs_block_group *bg, |
|
struct find_free_extent_ctl *ffe_ctl) |
|
{ |
|
struct btrfs_free_cluster *last_ptr = ffe_ctl->last_ptr; |
|
u64 offset; |
|
|
|
/* |
|
* We are doing an unclustered allocation, set the fragmented flag so |
|
* we don't bother trying to setup a cluster again until we get more |
|
* space. |
|
*/ |
|
if (unlikely(last_ptr)) { |
|
spin_lock(&last_ptr->lock); |
|
last_ptr->fragmented = 1; |
|
spin_unlock(&last_ptr->lock); |
|
} |
|
if (ffe_ctl->cached) { |
|
struct btrfs_free_space_ctl *free_space_ctl; |
|
|
|
free_space_ctl = bg->free_space_ctl; |
|
spin_lock(&free_space_ctl->tree_lock); |
|
if (free_space_ctl->free_space < |
|
ffe_ctl->num_bytes + ffe_ctl->empty_cluster + |
|
ffe_ctl->empty_size) { |
|
ffe_ctl->total_free_space = max_t(u64, |
|
ffe_ctl->total_free_space, |
|
free_space_ctl->free_space); |
|
spin_unlock(&free_space_ctl->tree_lock); |
|
return 1; |
|
} |
|
spin_unlock(&free_space_ctl->tree_lock); |
|
} |
|
|
|
offset = btrfs_find_space_for_alloc(bg, ffe_ctl->search_start, |
|
ffe_ctl->num_bytes, ffe_ctl->empty_size, |
|
&ffe_ctl->max_extent_size); |
|
|
|
/* |
|
* If we didn't find a chunk, and we haven't failed on this block group |
|
* before, and this block group is in the middle of caching and we are |
|
* ok with waiting, then go ahead and wait for progress to be made, and |
|
* set @retry_unclustered to true. |
|
* |
|
* If @retry_unclustered is true then we've already waited on this |
|
* block group once and should move on to the next block group. |
|
*/ |
|
if (!offset && !ffe_ctl->retry_unclustered && !ffe_ctl->cached && |
|
ffe_ctl->loop > LOOP_CACHING_NOWAIT) { |
|
btrfs_wait_block_group_cache_progress(bg, ffe_ctl->num_bytes + |
|
ffe_ctl->empty_size); |
|
ffe_ctl->retry_unclustered = true; |
|
return -EAGAIN; |
|
} else if (!offset) { |
|
return 1; |
|
} |
|
ffe_ctl->found_offset = offset; |
|
return 0; |
|
} |
|
|
|
static int do_allocation_clustered(struct btrfs_block_group *block_group, |
|
struct find_free_extent_ctl *ffe_ctl, |
|
struct btrfs_block_group **bg_ret) |
|
{ |
|
int ret; |
|
|
|
/* We want to try and use the cluster allocator, so lets look there */ |
|
if (ffe_ctl->last_ptr && ffe_ctl->use_cluster) { |
|
ret = find_free_extent_clustered(block_group, ffe_ctl, bg_ret); |
|
if (ret >= 0 || ret == -EAGAIN) |
|
return ret; |
|
/* ret == -ENOENT case falls through */ |
|
} |
|
|
|
return find_free_extent_unclustered(block_group, ffe_ctl); |
|
} |
|
|
|
/* |
|
* Tree-log block group locking |
|
* ============================ |
|
* |
|
* fs_info::treelog_bg_lock protects the fs_info::treelog_bg which |
|
* indicates the starting address of a block group, which is reserved only |
|
* for tree-log metadata. |
|
* |
|
* Lock nesting |
|
* ============ |
|
* |
|
* space_info::lock |
|
* block_group::lock |
|
* fs_info::treelog_bg_lock |
|
*/ |
|
|
|
/* |
|
* Simple allocator for sequential-only block group. It only allows sequential |
|
* allocation. No need to play with trees. This function also reserves the |
|
* bytes as in btrfs_add_reserved_bytes. |
|
*/ |
|
static int do_allocation_zoned(struct btrfs_block_group *block_group, |
|
struct find_free_extent_ctl *ffe_ctl, |
|
struct btrfs_block_group **bg_ret) |
|
{ |
|
struct btrfs_fs_info *fs_info = block_group->fs_info; |
|
struct btrfs_space_info *space_info = block_group->space_info; |
|
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl; |
|
u64 start = block_group->start; |
|
u64 num_bytes = ffe_ctl->num_bytes; |
|
u64 avail; |
|
u64 bytenr = block_group->start; |
|
u64 log_bytenr; |
|
u64 data_reloc_bytenr; |
|
int ret = 0; |
|
bool skip = false; |
|
|
|
ASSERT(btrfs_is_zoned(block_group->fs_info)); |
|
|
|
/* |
|
* Do not allow non-tree-log blocks in the dedicated tree-log block |
|
* group, and vice versa. |
|
*/ |
|
spin_lock(&fs_info->treelog_bg_lock); |
|
log_bytenr = fs_info->treelog_bg; |
|
if (log_bytenr && ((ffe_ctl->for_treelog && bytenr != log_bytenr) || |
|
(!ffe_ctl->for_treelog && bytenr == log_bytenr))) |
|
skip = true; |
|
spin_unlock(&fs_info->treelog_bg_lock); |
|
if (skip) |
|
return 1; |
|
|
|
/* |
|
* Do not allow non-relocation blocks in the dedicated relocation block |
|
* group, and vice versa. |
|
*/ |
|
spin_lock(&fs_info->relocation_bg_lock); |
|
data_reloc_bytenr = fs_info->data_reloc_bg; |
|
if (data_reloc_bytenr && |
|
((ffe_ctl->for_data_reloc && bytenr != data_reloc_bytenr) || |
|
(!ffe_ctl->for_data_reloc && bytenr == data_reloc_bytenr))) |
|
skip = true; |
|
spin_unlock(&fs_info->relocation_bg_lock); |
|
if (skip) |
|
return 1; |
|
|
|
/* Check RO and no space case before trying to activate it */ |
|
spin_lock(&block_group->lock); |
|
if (block_group->ro || |
|
block_group->alloc_offset == block_group->zone_capacity) { |
|
ret = 1; |
|
/* |
|
* May need to clear fs_info->{treelog,data_reloc}_bg. |
|
* Return the error after taking the locks. |
|
*/ |
|
} |
|
spin_unlock(&block_group->lock); |
|
|
|
if (!ret && !btrfs_zone_activate(block_group)) { |
|
ret = 1; |
|
/* |
|
* May need to clear fs_info->{treelog,data_reloc}_bg. |
|
* Return the error after taking the locks. |
|
*/ |
|
} |
|
|
|
spin_lock(&space_info->lock); |
|
spin_lock(&block_group->lock); |
|
spin_lock(&fs_info->treelog_bg_lock); |
|
spin_lock(&fs_info->relocation_bg_lock); |
|
|
|
if (ret) |
|
goto out; |
|
|
|
ASSERT(!ffe_ctl->for_treelog || |
|
block_group->start == fs_info->treelog_bg || |
|
fs_info->treelog_bg == 0); |
|
ASSERT(!ffe_ctl->for_data_reloc || |
|
block_group->start == fs_info->data_reloc_bg || |
|
fs_info->data_reloc_bg == 0); |
|
|
|
if (block_group->ro) { |
|
ret = 1; |
|
goto out; |
|
} |
|
|
|
/* |
|
* Do not allow currently using block group to be tree-log dedicated |
|
* block group. |
|
*/ |
|
if (ffe_ctl->for_treelog && !fs_info->treelog_bg && |
|
(block_group->used || block_group->reserved)) { |
|
ret = 1; |
|
goto out; |
|
} |
|
|
|
/* |
|
* Do not allow currently used block group to be the data relocation |
|
* dedicated block group. |
|
*/ |
|
if (ffe_ctl->for_data_reloc && !fs_info->data_reloc_bg && |
|
(block_group->used || block_group->reserved)) { |
|
ret = 1; |
|
goto out; |
|
} |
|
|
|
WARN_ON_ONCE(block_group->alloc_offset > block_group->zone_capacity); |
|
avail = block_group->zone_capacity - block_group->alloc_offset; |
|
if (avail < num_bytes) { |
|
if (ffe_ctl->max_extent_size < avail) { |
|
/* |
|
* With sequential allocator, free space is always |
|
* contiguous |
|
*/ |
|
ffe_ctl->max_extent_size = avail; |
|
ffe_ctl->total_free_space = avail; |
|
} |
|
ret = 1; |
|
goto out; |
|
} |
|
|
|
if (ffe_ctl->for_treelog && !fs_info->treelog_bg) |
|
fs_info->treelog_bg = block_group->start; |
|
|
|
if (ffe_ctl->for_data_reloc && !fs_info->data_reloc_bg) |
|
fs_info->data_reloc_bg = block_group->start; |
|
|
|
ffe_ctl->found_offset = start + block_group->alloc_offset; |
|
block_group->alloc_offset += num_bytes; |
|
spin_lock(&ctl->tree_lock); |
|
ctl->free_space -= num_bytes; |
|
spin_unlock(&ctl->tree_lock); |
|
|
|
/* |
|
* We do not check if found_offset is aligned to stripesize. The |
|
* address is anyway rewritten when using zone append writing. |
|
*/ |
|
|
|
ffe_ctl->search_start = ffe_ctl->found_offset; |
|
|
|
out: |
|
if (ret && ffe_ctl->for_treelog) |
|
fs_info->treelog_bg = 0; |
|
if (ret && ffe_ctl->for_data_reloc) |
|
fs_info->data_reloc_bg = 0; |
|
spin_unlock(&fs_info->relocation_bg_lock); |
|
spin_unlock(&fs_info->treelog_bg_lock); |
|
spin_unlock(&block_group->lock); |
|
spin_unlock(&space_info->lock); |
|
return ret; |
|
} |
|
|
|
static int do_allocation(struct btrfs_block_group *block_group, |
|
struct find_free_extent_ctl *ffe_ctl, |
|
struct btrfs_block_group **bg_ret) |
|
{ |
|
switch (ffe_ctl->policy) { |
|
case BTRFS_EXTENT_ALLOC_CLUSTERED: |
|
return do_allocation_clustered(block_group, ffe_ctl, bg_ret); |
|
case BTRFS_EXTENT_ALLOC_ZONED: |
|
return do_allocation_zoned(block_group, ffe_ctl, bg_ret); |
|
default: |
|
BUG(); |
|
} |
|
} |
|
|
|
static void release_block_group(struct btrfs_block_group *block_group, |
|
struct find_free_extent_ctl *ffe_ctl, |
|
int delalloc) |
|
{ |
|
switch (ffe_ctl->policy) { |
|
case BTRFS_EXTENT_ALLOC_CLUSTERED: |
|
ffe_ctl->retry_clustered = false; |
|
ffe_ctl->retry_unclustered = false; |
|
break; |
|
case BTRFS_EXTENT_ALLOC_ZONED: |
|
/* Nothing to do */ |
|
break; |
|
default: |
|
BUG(); |
|
} |
|
|
|
BUG_ON(btrfs_bg_flags_to_raid_index(block_group->flags) != |
|
ffe_ctl->index); |
|
btrfs_release_block_group(block_group, delalloc); |
|
} |
|
|
|
static void found_extent_clustered(struct find_free_extent_ctl *ffe_ctl, |
|
struct btrfs_key *ins) |
|
{ |
|
struct btrfs_free_cluster *last_ptr = ffe_ctl->last_ptr; |
|
|
|
if (!ffe_ctl->use_cluster && last_ptr) { |
|
spin_lock(&last_ptr->lock); |
|
last_ptr->window_start = ins->objectid; |
|
spin_unlock(&last_ptr->lock); |
|
} |
|
} |
|
|
|
static void found_extent(struct find_free_extent_ctl *ffe_ctl, |
|
struct btrfs_key *ins) |
|
{ |
|
switch (ffe_ctl->policy) { |
|
case BTRFS_EXTENT_ALLOC_CLUSTERED: |
|
found_extent_clustered(ffe_ctl, ins); |
|
break; |
|
case BTRFS_EXTENT_ALLOC_ZONED: |
|
/* Nothing to do */ |
|
break; |
|
default: |
|
BUG(); |
|
} |
|
} |
|
|
|
static bool can_allocate_chunk(struct btrfs_fs_info *fs_info, |
|
struct find_free_extent_ctl *ffe_ctl) |
|
{ |
|
switch (ffe_ctl->policy) { |
|
case BTRFS_EXTENT_ALLOC_CLUSTERED: |
|
return true; |
|
case BTRFS_EXTENT_ALLOC_ZONED: |
|
/* |
|
* If we have enough free space left in an already |
|
* active block group and we can't activate any other |
|
* zone now, do not allow allocating a new chunk and |
|
* let find_free_extent() retry with a smaller size. |
|
*/ |
|
if (ffe_ctl->max_extent_size >= ffe_ctl->min_alloc_size && |
|
!btrfs_can_activate_zone(fs_info->fs_devices, ffe_ctl->flags)) |
|
return false; |
|
return true; |
|
default: |
|
BUG(); |
|
} |
|
} |
|
|
|
static int chunk_allocation_failed(struct find_free_extent_ctl *ffe_ctl) |
|
{ |
|
switch (ffe_ctl->policy) { |
|
case BTRFS_EXTENT_ALLOC_CLUSTERED: |
|
/* |
|
* If we can't allocate a new chunk we've already looped through |
|
* at least once, move on to the NO_EMPTY_SIZE case. |
|
*/ |
|
ffe_ctl->loop = LOOP_NO_EMPTY_SIZE; |
|
return 0; |
|
case BTRFS_EXTENT_ALLOC_ZONED: |
|
/* Give up here */ |
|
return -ENOSPC; |
|
default: |
|
BUG(); |
|
} |
|
} |
|
|
|
/* |
|
* Return >0 means caller needs to re-search for free extent |
|
* Return 0 means we have the needed free extent. |
|
* Return <0 means we failed to locate any free extent. |
|
*/ |
|
static int find_free_extent_update_loop(struct btrfs_fs_info *fs_info, |
|
struct btrfs_key *ins, |
|
struct find_free_extent_ctl *ffe_ctl, |
|
bool full_search) |
|
{ |
|
struct btrfs_root *root = fs_info->chunk_root; |
|
int ret; |
|
|
|
if ((ffe_ctl->loop == LOOP_CACHING_NOWAIT) && |
|
ffe_ctl->have_caching_bg && !ffe_ctl->orig_have_caching_bg) |
|
ffe_ctl->orig_have_caching_bg = true; |
|
|
|
if (ins->objectid) { |
|
found_extent(ffe_ctl, ins); |
|
return 0; |
|
} |
|
|
|
if (ffe_ctl->loop >= LOOP_CACHING_WAIT && ffe_ctl->have_caching_bg) |
|
return 1; |
|
|
|
ffe_ctl->index++; |
|
if (ffe_ctl->index < BTRFS_NR_RAID_TYPES) |
|
return 1; |
|
|
|
/* |
|
* LOOP_CACHING_NOWAIT, search partially cached block groups, kicking |
|
* caching kthreads as we move along |
|
* LOOP_CACHING_WAIT, search everything, and wait if our bg is caching |
|
* LOOP_ALLOC_CHUNK, force a chunk allocation and try again |
|
* LOOP_NO_EMPTY_SIZE, set empty_size and empty_cluster to 0 and try |
|
* again |
|
*/ |
|
if (ffe_ctl->loop < LOOP_NO_EMPTY_SIZE) { |
|
ffe_ctl->index = 0; |
|
if (ffe_ctl->loop == LOOP_CACHING_NOWAIT) { |
|
/* |
|
* We want to skip the LOOP_CACHING_WAIT step if we |
|
* don't have any uncached bgs and we've already done a |
|
* full search through. |
|
*/ |
|
if (ffe_ctl->orig_have_caching_bg || !full_search) |
|
ffe_ctl->loop = LOOP_CACHING_WAIT; |
|
else |
|
ffe_ctl->loop = LOOP_ALLOC_CHUNK; |
|
} else { |
|
ffe_ctl->loop++; |
|
} |
|
|
|
if (ffe_ctl->loop == LOOP_ALLOC_CHUNK) { |
|
struct btrfs_trans_handle *trans; |
|
int exist = 0; |
|
|
|
/*Check if allocation policy allows to create a new chunk */ |
|
if (!can_allocate_chunk(fs_info, ffe_ctl)) |
|
return -ENOSPC; |
|
|
|
trans = current->journal_info; |
|
if (trans) |
|
exist = 1; |
|
else |
|
trans = btrfs_join_transaction(root); |
|
|
|
if (IS_ERR(trans)) { |
|
ret = PTR_ERR(trans); |
|
return ret; |
|
} |
|
|
|
ret = btrfs_chunk_alloc(trans, ffe_ctl->flags, |
|
CHUNK_ALLOC_FORCE); |
|
|
|
/* Do not bail out on ENOSPC since we can do more. */ |
|
if (ret == -ENOSPC) |
|
ret = chunk_allocation_failed(ffe_ctl); |
|
else if (ret < 0) |
|
btrfs_abort_transaction(trans, ret); |
|
else |
|
ret = 0; |
|
if (!exist) |
|
btrfs_end_transaction(trans); |
|
if (ret) |
|
return ret; |
|
} |
|
|
|
if (ffe_ctl->loop == LOOP_NO_EMPTY_SIZE) { |
|
if (ffe_ctl->policy != BTRFS_EXTENT_ALLOC_CLUSTERED) |
|
return -ENOSPC; |
|
|
|
/* |
|
* Don't loop again if we already have no empty_size and |
|
* no empty_cluster. |
|
*/ |
|
if (ffe_ctl->empty_size == 0 && |
|
ffe_ctl->empty_cluster == 0) |
|
return -ENOSPC; |
|
ffe_ctl->empty_size = 0; |
|
ffe_ctl->empty_cluster = 0; |
|
} |
|
return 1; |
|
} |
|
return -ENOSPC; |
|
} |
|
|
|
static int prepare_allocation_clustered(struct btrfs_fs_info *fs_info, |
|
struct find_free_extent_ctl *ffe_ctl, |
|
struct btrfs_space_info *space_info, |
|
struct btrfs_key *ins) |
|
{ |
|
/* |
|
* If our free space is heavily fragmented we may not be able to make |
|
* big contiguous allocations, so instead of doing the expensive search |
|
* for free space, simply return ENOSPC with our max_extent_size so we |
|
* can go ahead and search for a more manageable chunk. |
|
* |
|
* If our max_extent_size is large enough for our allocation simply |
|
* disable clustering since we will likely not be able to find enough |
|
* space to create a cluster and induce latency trying. |
|
*/ |
|
if (space_info->max_extent_size) { |
|
spin_lock(&space_info->lock); |
|
if (space_info->max_extent_size && |
|
ffe_ctl->num_bytes > space_info->max_extent_size) { |
|
ins->offset = space_info->max_extent_size; |
|
spin_unlock(&space_info->lock); |
|
return -ENOSPC; |
|
} else if (space_info->max_extent_size) { |
|
ffe_ctl->use_cluster = false; |
|
} |
|
spin_unlock(&space_info->lock); |
|
} |
|
|
|
ffe_ctl->last_ptr = fetch_cluster_info(fs_info, space_info, |
|
&ffe_ctl->empty_cluster); |
|
if (ffe_ctl->last_ptr) { |
|
struct btrfs_free_cluster *last_ptr = ffe_ctl->last_ptr; |
|
|
|
spin_lock(&last_ptr->lock); |
|
if (last_ptr->block_group) |
|
ffe_ctl->hint_byte = last_ptr->window_start; |
|
if (last_ptr->fragmented) { |
|
/* |
|
* We still set window_start so we can keep track of the |
|
* last place we found an allocation to try and save |
|
* some time. |
|
*/ |
|
ffe_ctl->hint_byte = last_ptr->window_start; |
|
ffe_ctl->use_cluster = false; |
|
} |
|
spin_unlock(&last_ptr->lock); |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static int prepare_allocation(struct btrfs_fs_info *fs_info, |
|
struct find_free_extent_ctl *ffe_ctl, |
|
struct btrfs_space_info *space_info, |
|
struct btrfs_key *ins) |
|
{ |
|
switch (ffe_ctl->policy) { |
|
case BTRFS_EXTENT_ALLOC_CLUSTERED: |
|
return prepare_allocation_clustered(fs_info, ffe_ctl, |
|
space_info, ins); |
|
case BTRFS_EXTENT_ALLOC_ZONED: |
|
if (ffe_ctl->for_treelog) { |
|
spin_lock(&fs_info->treelog_bg_lock); |
|
if (fs_info->treelog_bg) |
|
ffe_ctl->hint_byte = fs_info->treelog_bg; |
|
spin_unlock(&fs_info->treelog_bg_lock); |
|
} |
|
if (ffe_ctl->for_data_reloc) { |
|
spin_lock(&fs_info->relocation_bg_lock); |
|
if (fs_info->data_reloc_bg) |
|
ffe_ctl->hint_byte = fs_info->data_reloc_bg; |
|
spin_unlock(&fs_info->relocation_bg_lock); |
|
} |
|
return 0; |
|
default: |
|
BUG(); |
|
} |
|
} |
|
|
|
/* |
|
* 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 == start position |
|
* ins->flags = BTRFS_EXTENT_ITEM_KEY |
|
* ins->offset == the size of the hole. |
|
* Any available blocks before search_start are skipped. |
|
* |
|
* If there is no suitable free space, we will record the max size of |
|
* the free space extent currently. |
|
* |
|
* The overall logic and call chain: |
|
* |
|
* find_free_extent() |
|
* |- Iterate through all block groups |
|
* | |- Get a valid block group |
|
* | |- Try to do clustered allocation in that block group |
|
* | |- Try to do unclustered allocation in that block group |
|
* | |- Check if the result is valid |
|
* | | |- If valid, then exit |
|
* | |- Jump to next block group |
|
* | |
|
* |- Push harder to find free extents |
|
* |- If not found, re-iterate all block groups |
|
*/ |
|
static noinline int find_free_extent(struct btrfs_root *root, |
|
struct btrfs_key *ins, |
|
struct find_free_extent_ctl *ffe_ctl) |
|
{ |
|
struct btrfs_fs_info *fs_info = root->fs_info; |
|
int ret = 0; |
|
int cache_block_group_error = 0; |
|
struct btrfs_block_group *block_group = NULL; |
|
struct btrfs_space_info *space_info; |
|
bool full_search = false; |
|
|
|
WARN_ON(ffe_ctl->num_bytes < fs_info->sectorsize); |
|
|
|
ffe_ctl->search_start = 0; |
|
/* For clustered allocation */ |
|
ffe_ctl->empty_cluster = 0; |
|
ffe_ctl->last_ptr = NULL; |
|
ffe_ctl->use_cluster = true; |
|
ffe_ctl->have_caching_bg = false; |
|
ffe_ctl->orig_have_caching_bg = false; |
|
ffe_ctl->index = btrfs_bg_flags_to_raid_index(ffe_ctl->flags); |
|
ffe_ctl->loop = 0; |
|
/* For clustered allocation */ |
|
ffe_ctl->retry_clustered = false; |
|
ffe_ctl->retry_unclustered = false; |
|
ffe_ctl->cached = 0; |
|
ffe_ctl->max_extent_size = 0; |
|
ffe_ctl->total_free_space = 0; |
|
ffe_ctl->found_offset = 0; |
|
ffe_ctl->policy = BTRFS_EXTENT_ALLOC_CLUSTERED; |
|
|
|
if (btrfs_is_zoned(fs_info)) |
|
ffe_ctl->policy = BTRFS_EXTENT_ALLOC_ZONED; |
|
|
|
ins->type = BTRFS_EXTENT_ITEM_KEY; |
|
ins->objectid = 0; |
|
ins->offset = 0; |
|
|
|
trace_find_free_extent(root, ffe_ctl->num_bytes, ffe_ctl->empty_size, |
|
ffe_ctl->flags); |
|
|
|
space_info = btrfs_find_space_info(fs_info, ffe_ctl->flags); |
|
if (!space_info) { |
|
btrfs_err(fs_info, "No space info for %llu", ffe_ctl->flags); |
|
return -ENOSPC; |
|
} |
|
|
|
ret = prepare_allocation(fs_info, ffe_ctl, space_info, ins); |
|
if (ret < 0) |
|
return ret; |
|
|
|
ffe_ctl->search_start = max(ffe_ctl->search_start, |
|
first_logical_byte(fs_info, 0)); |
|
ffe_ctl->search_start = max(ffe_ctl->search_start, ffe_ctl->hint_byte); |
|
if (ffe_ctl->search_start == ffe_ctl->hint_byte) { |
|
block_group = btrfs_lookup_block_group(fs_info, |
|
ffe_ctl->search_start); |
|
/* |
|
* we don't want to use the block group if it doesn't match our |
|
* allocation bits, or if its not cached. |
|
* |
|
* However if we are re-searching with an ideal block group |
|
* picked out then we don't care that the block group is cached. |
|
*/ |
|
if (block_group && block_group_bits(block_group, ffe_ctl->flags) && |
|
block_group->cached != BTRFS_CACHE_NO) { |
|
down_read(&space_info->groups_sem); |
|
if (list_empty(&block_group->list) || |
|
block_group->ro) { |
|
/* |
|
* someone is removing this block group, |
|
* we can't jump into the have_block_group |
|
* target because our list pointers are not |
|
* valid |
|
*/ |
|
btrfs_put_block_group(block_group); |
|
up_read(&space_info->groups_sem); |
|
} else { |
|
ffe_ctl->index = btrfs_bg_flags_to_raid_index( |
|
block_group->flags); |
|
btrfs_lock_block_group(block_group, |
|
ffe_ctl->delalloc); |
|
goto have_block_group; |
|
} |
|
} else if (block_group) { |
|
btrfs_put_block_group(block_group); |
|
} |
|
} |
|
search: |
|
ffe_ctl->have_caching_bg = false; |
|
if (ffe_ctl->index == btrfs_bg_flags_to_raid_index(ffe_ctl->flags) || |
|
ffe_ctl->index == 0) |
|
full_search = true; |
|
down_read(&space_info->groups_sem); |
|
list_for_each_entry(block_group, |
|
&space_info->block_groups[ffe_ctl->index], list) { |
|
struct btrfs_block_group *bg_ret; |
|
|
|
/* If the block group is read-only, we can skip it entirely. */ |
|
if (unlikely(block_group->ro)) { |
|
if (ffe_ctl->for_treelog) |
|
btrfs_clear_treelog_bg(block_group); |
|
if (ffe_ctl->for_data_reloc) |
|
btrfs_clear_data_reloc_bg(block_group); |
|
continue; |
|
} |
|
|
|
btrfs_grab_block_group(block_group, ffe_ctl->delalloc); |
|
ffe_ctl->search_start = block_group->start; |
|
|
|
/* |
|
* this can happen if we end up cycling through all the |
|
* raid types, but we want to make sure we only allocate |
|
* for the proper type. |
|
*/ |
|
if (!block_group_bits(block_group, ffe_ctl->flags)) { |
|
u64 extra = BTRFS_BLOCK_GROUP_DUP | |
|
BTRFS_BLOCK_GROUP_RAID1_MASK | |
|
BTRFS_BLOCK_GROUP_RAID56_MASK | |
|
BTRFS_BLOCK_GROUP_RAID10; |
|
|
|
/* |
|
* if they asked for extra copies and this block group |
|
* doesn't provide them, bail. This does allow us to |
|
* fill raid0 from raid1. |
|
*/ |
|
if ((ffe_ctl->flags & extra) && !(block_group->flags & extra)) |
|
goto loop; |
|
|
|
/* |
|
* This block group has different flags than we want. |
|
* It's possible that we have MIXED_GROUP flag but no |
|
* block group is mixed. Just skip such block group. |
|
*/ |
|
btrfs_release_block_group(block_group, ffe_ctl->delalloc); |
|
continue; |
|
} |
|
|
|
have_block_group: |
|
ffe_ctl->cached = btrfs_block_group_done(block_group); |
|
if (unlikely(!ffe_ctl->cached)) { |
|
ffe_ctl->have_caching_bg = true; |
|
ret = btrfs_cache_block_group(block_group, 0); |
|
|
|
/* |
|
* If we get ENOMEM here or something else we want to |
|
* try other block groups, because it may not be fatal. |
|
* However if we can't find anything else we need to |
|
* save our return here so that we return the actual |
|
* error that caused problems, not ENOSPC. |
|
*/ |
|
if (ret < 0) { |
|
if (!cache_block_group_error) |
|
cache_block_group_error = ret; |
|
ret = 0; |
|
goto loop; |
|
} |
|
ret = 0; |
|
} |
|
|
|
if (unlikely(block_group->cached == BTRFS_CACHE_ERROR)) |
|
goto loop; |
|
|
|
bg_ret = NULL; |
|
ret = do_allocation(block_group, ffe_ctl, &bg_ret); |
|
if (ret == 0) { |
|
if (bg_ret && bg_ret != block_group) { |
|
btrfs_release_block_group(block_group, |
|
ffe_ctl->delalloc); |
|
block_group = bg_ret; |
|
} |
|
} else if (ret == -EAGAIN) { |
|
goto have_block_group; |
|
} else if (ret > 0) { |
|
goto loop; |
|
} |
|
|
|
/* Checks */ |
|
ffe_ctl->search_start = round_up(ffe_ctl->found_offset, |
|
fs_info->stripesize); |
|
|
|
/* move on to the next group */ |
|
if (ffe_ctl->search_start + ffe_ctl->num_bytes > |
|
block_group->start + block_group->length) { |
|
btrfs_add_free_space_unused(block_group, |
|
ffe_ctl->found_offset, |
|
ffe_ctl->num_bytes); |
|
goto loop; |
|
} |
|
|
|
if (ffe_ctl->found_offset < ffe_ctl->search_start) |
|
btrfs_add_free_space_unused(block_group, |
|
ffe_ctl->found_offset, |
|
ffe_ctl->search_start - ffe_ctl->found_offset); |
|
|
|
ret = btrfs_add_reserved_bytes(block_group, ffe_ctl->ram_bytes, |
|
ffe_ctl->num_bytes, |
|
ffe_ctl->delalloc); |
|
if (ret == -EAGAIN) { |
|
btrfs_add_free_space_unused(block_group, |
|
ffe_ctl->found_offset, |
|
ffe_ctl->num_bytes); |
|
goto loop; |
|
} |
|
btrfs_inc_block_group_reservations(block_group); |
|
|
|
/* we are all good, lets return */ |
|
ins->objectid = ffe_ctl->search_start; |
|
ins->offset = ffe_ctl->num_bytes; |
|
|
|
trace_btrfs_reserve_extent(block_group, ffe_ctl->search_start, |
|
ffe_ctl->num_bytes); |
|
btrfs_release_block_group(block_group, ffe_ctl->delalloc); |
|
break; |
|
loop: |
|
release_block_group(block_group, ffe_ctl, ffe_ctl->delalloc); |
|
cond_resched(); |
|
} |
|
up_read(&space_info->groups_sem); |
|
|
|
ret = find_free_extent_update_loop(fs_info, ins, ffe_ctl, full_search); |
|
if (ret > 0) |
|
goto search; |
|
|
|
if (ret == -ENOSPC && !cache_block_group_error) { |
|
/* |
|
* Use ffe_ctl->total_free_space as fallback if we can't find |
|
* any contiguous hole. |
|
*/ |
|
if (!ffe_ctl->max_extent_size) |
|
ffe_ctl->max_extent_size = ffe_ctl->total_free_space; |
|
spin_lock(&space_info->lock); |
|
space_info->max_extent_size = ffe_ctl->max_extent_size; |
|
spin_unlock(&space_info->lock); |
|
ins->offset = ffe_ctl->max_extent_size; |
|
} else if (ret == -ENOSPC) { |
|
ret = cache_block_group_error; |
|
} |
|
return ret; |
|
} |
|
|
|
/* |
|
* btrfs_reserve_extent - entry point to the extent allocator. Tries to find a |
|
* hole that is at least as big as @num_bytes. |
|
* |
|
* @root - The root that will contain this extent |
|
* |
|
* @ram_bytes - The amount of space in ram that @num_bytes take. This |
|
* is used for accounting purposes. This value differs |
|
* from @num_bytes only in the case of compressed extents. |
|
* |
|
* @num_bytes - Number of bytes to allocate on-disk. |
|
* |
|
* @min_alloc_size - Indicates the minimum amount of space that the |
|
* allocator should try to satisfy. In some cases |
|
* @num_bytes may be larger than what is required and if |
|
* the filesystem is fragmented then allocation fails. |
|
* However, the presence of @min_alloc_size gives a |
|
* chance to try and satisfy the smaller allocation. |
|
* |
|
* @empty_size - A hint that you plan on doing more COW. This is the |
|
* size in bytes the allocator should try to find free |
|
* next to the block it returns. This is just a hint and |
|
* may be ignored by the allocator. |
|
* |
|
* @hint_byte - Hint to the allocator to start searching above the byte |
|
* address passed. It might be ignored. |
|
* |
|
* @ins - This key is modified to record the found hole. It will |
|
* have the following values: |
|
* ins->objectid == start position |
|
* ins->flags = BTRFS_EXTENT_ITEM_KEY |
|
* ins->offset == the size of the hole. |
|
* |
|
* @is_data - Boolean flag indicating whether an extent is |
|
* allocated for data (true) or metadata (false) |
|
* |
|
* @delalloc - Boolean flag indicating whether this allocation is for |
|
* delalloc or not. If 'true' data_rwsem of block groups |
|
* is going to be acquired. |
|
* |
|
* |
|
* Returns 0 when an allocation succeeded or < 0 when an error occurred. In |
|
* case -ENOSPC is returned then @ins->offset will contain the size of the |
|
* largest available hole the allocator managed to find. |
|
*/ |
|
int btrfs_reserve_extent(struct btrfs_root *root, u64 ram_bytes, |
|
u64 num_bytes, u64 min_alloc_size, |
|
u64 empty_size, u64 hint_byte, |
|
struct btrfs_key *ins, int is_data, int delalloc) |
|
{ |
|
struct btrfs_fs_info *fs_info = root->fs_info; |
|
struct find_free_extent_ctl ffe_ctl = {}; |
|
bool final_tried = num_bytes == min_alloc_size; |
|
u64 flags; |
|
int ret; |
|
bool for_treelog = (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID); |
|
bool for_data_reloc = (btrfs_is_data_reloc_root(root) && is_data); |
|
|
|
flags = get_alloc_profile_by_root(root, is_data); |
|
again: |
|
WARN_ON(num_bytes < fs_info->sectorsize); |
|
|
|
ffe_ctl.ram_bytes = ram_bytes; |
|
ffe_ctl.num_bytes = num_bytes; |
|
ffe_ctl.min_alloc_size = min_alloc_size; |
|
ffe_ctl.empty_size = empty_size; |
|
ffe_ctl.flags = flags; |
|
ffe_ctl.delalloc = delalloc; |
|
ffe_ctl.hint_byte = hint_byte; |
|
ffe_ctl.for_treelog = for_treelog; |
|
ffe_ctl.for_data_reloc = for_data_reloc; |
|
|
|
ret = find_free_extent(root, ins, &ffe_ctl); |
|
if (!ret && !is_data) { |
|
btrfs_dec_block_group_reservations(fs_info, ins->objectid); |
|
} else if (ret == -ENOSPC) { |
|
if (!final_tried && ins->offset) { |
|
num_bytes = min(num_bytes >> 1, ins->offset); |
|
num_bytes = round_down(num_bytes, |
|
fs_info->sectorsize); |
|
num_bytes = max(num_bytes, min_alloc_size); |
|
ram_bytes = num_bytes; |
|
if (num_bytes == min_alloc_size) |
|
final_tried = true; |
|
goto again; |
|
} else if (btrfs_test_opt(fs_info, ENOSPC_DEBUG)) { |
|
struct btrfs_space_info *sinfo; |
|
|
|
sinfo = btrfs_find_space_info(fs_info, flags); |
|
btrfs_err(fs_info, |
|
"allocation failed flags %llu, wanted %llu tree-log %d, relocation: %d", |
|
flags, num_bytes, for_treelog, for_data_reloc); |
|
if (sinfo) |
|
btrfs_dump_space_info(fs_info, sinfo, |
|
num_bytes, 1); |
|
} |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
int btrfs_free_reserved_extent(struct btrfs_fs_info *fs_info, |
|
u64 start, u64 len, int delalloc) |
|
{ |
|
struct btrfs_block_group *cache; |
|
|
|
cache = btrfs_lookup_block_group(fs_info, start); |
|
if (!cache) { |
|
btrfs_err(fs_info, "Unable to find block group for %llu", |
|
start); |
|
return -ENOSPC; |
|
} |
|
|
|
btrfs_add_free_space(cache, start, len); |
|
btrfs_free_reserved_bytes(cache, len, delalloc); |
|
trace_btrfs_reserved_extent_free(fs_info, start, len); |
|
|
|
btrfs_put_block_group(cache); |
|
return 0; |
|
} |
|
|
|
int btrfs_pin_reserved_extent(struct btrfs_trans_handle *trans, u64 start, |
|
u64 len) |
|
{ |
|
struct btrfs_block_group *cache; |
|
int ret = 0; |
|
|
|
cache = btrfs_lookup_block_group(trans->fs_info, start); |
|
if (!cache) { |
|
btrfs_err(trans->fs_info, "unable to find block group for %llu", |
|
start); |
|
return -ENOSPC; |
|
} |
|
|
|
ret = pin_down_extent(trans, cache, start, len, 1); |
|
btrfs_put_block_group(cache); |
|
return ret; |
|
} |
|
|
|
static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans, |
|
u64 parent, u64 root_objectid, |
|
u64 flags, u64 owner, u64 offset, |
|
struct btrfs_key *ins, int ref_mod) |
|
{ |
|
struct btrfs_fs_info *fs_info = trans->fs_info; |
|
struct btrfs_root *extent_root; |
|
int ret; |
|
struct btrfs_extent_item *extent_item; |
|
struct btrfs_extent_inline_ref *iref; |
|
struct btrfs_path *path; |
|
struct extent_buffer *leaf; |
|
int type; |
|
u32 size; |
|
|
|
if (parent > 0) |
|
type = BTRFS_SHARED_DATA_REF_KEY; |
|
else |
|
type = BTRFS_EXTENT_DATA_REF_KEY; |
|
|
|
size = sizeof(*extent_item) + btrfs_extent_inline_ref_size(type); |
|
|
|
path = btrfs_alloc_path(); |
|
if (!path) |
|
return -ENOMEM; |
|
|
|
extent_root = btrfs_extent_root(fs_info, ins->objectid); |
|
ret = btrfs_insert_empty_item(trans, extent_root, path, ins, size); |
|
if (ret) { |
|
btrfs_free_path(path); |
|
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, ref_mod); |
|
btrfs_set_extent_generation(leaf, extent_item, trans->transid); |
|
btrfs_set_extent_flags(leaf, extent_item, |
|
flags | BTRFS_EXTENT_FLAG_DATA); |
|
|
|
iref = (struct btrfs_extent_inline_ref *)(extent_item + 1); |
|
btrfs_set_extent_inline_ref_type(leaf, iref, type); |
|
if (parent > 0) { |
|
struct btrfs_shared_data_ref *ref; |
|
ref = (struct btrfs_shared_data_ref *)(iref + 1); |
|
btrfs_set_extent_inline_ref_offset(leaf, iref, parent); |
|
btrfs_set_shared_data_ref_count(leaf, ref, ref_mod); |
|
} else { |
|
struct btrfs_extent_data_ref *ref; |
|
ref = (struct btrfs_extent_data_ref *)(&iref->offset); |
|
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, ref_mod); |
|
} |
|
|
|
btrfs_mark_buffer_dirty(path->nodes[0]); |
|
btrfs_free_path(path); |
|
|
|
ret = remove_from_free_space_tree(trans, ins->objectid, ins->offset); |
|
if (ret) |
|
return ret; |
|
|
|
ret = btrfs_update_block_group(trans, ins->objectid, ins->offset, true); |
|
if (ret) { /* -ENOENT, logic error */ |
|
btrfs_err(fs_info, "update block group failed for %llu %llu", |
|
ins->objectid, ins->offset); |
|
BUG(); |
|
} |
|
trace_btrfs_reserved_extent_alloc(fs_info, ins->objectid, ins->offset); |
|
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_fs_info *fs_info = trans->fs_info; |
|
struct btrfs_root *extent_root; |
|
int ret; |
|
struct btrfs_extent_item *extent_item; |
|
struct btrfs_key extent_key; |
|
struct btrfs_tree_block_info *block_info; |
|
struct btrfs_extent_inline_ref *iref; |
|
struct btrfs_path *path; |
|
struct extent_buffer *leaf; |
|
struct btrfs_delayed_tree_ref *ref; |
|
u32 size = sizeof(*extent_item) + sizeof(*iref); |
|
u64 num_bytes; |
|
u64 flags = extent_op->flags_to_set; |
|
bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA); |
|
|
|
ref = btrfs_delayed_node_to_tree_ref(node); |
|
|
|
extent_key.objectid = node->bytenr; |
|
if (skinny_metadata) { |
|
extent_key.offset = ref->level; |
|
extent_key.type = BTRFS_METADATA_ITEM_KEY; |
|
num_bytes = fs_info->nodesize; |
|
} else { |
|
extent_key.offset = node->num_bytes; |
|
extent_key.type = BTRFS_EXTENT_ITEM_KEY; |
|
size += sizeof(*block_info); |
|
num_bytes = node->num_bytes; |
|
} |
|
|
|
path = btrfs_alloc_path(); |
|
if (!path) |
|
return -ENOMEM; |
|
|
|
extent_root = btrfs_extent_root(fs_info, extent_key.objectid); |
|
ret = btrfs_insert_empty_item(trans, extent_root, path, &extent_key, |
|
size); |
|
if (ret) { |
|
btrfs_free_path(path); |
|
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, |
|
flags | BTRFS_EXTENT_FLAG_TREE_BLOCK); |
|
|
|
if (skinny_metadata) { |
|
iref = (struct btrfs_extent_inline_ref *)(extent_item + 1); |
|
} else { |
|
block_info = (struct btrfs_tree_block_info *)(extent_item + 1); |
|
btrfs_set_tree_block_key(leaf, block_info, &extent_op->key); |
|
btrfs_set_tree_block_level(leaf, block_info, ref->level); |
|
iref = (struct btrfs_extent_inline_ref *)(block_info + 1); |
|
} |
|
|
|
if (node->type == BTRFS_SHARED_BLOCK_REF_KEY) { |
|
btrfs_set_extent_inline_ref_type(leaf, iref, |
|
BTRFS_SHARED_BLOCK_REF_KEY); |
|
btrfs_set_extent_inline_ref_offset(leaf, iref, ref->parent); |
|
} else { |
|
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, extent_key.objectid, |
|
num_bytes); |
|
if (ret) |
|
return ret; |
|
|
|
ret = btrfs_update_block_group(trans, extent_key.objectid, |
|
fs_info->nodesize, true); |
|
if (ret) { /* -ENOENT, logic error */ |
|
btrfs_err(fs_info, "update block group failed for %llu %llu", |
|
extent_key.objectid, extent_key.offset); |
|
BUG(); |
|
} |
|
|
|
trace_btrfs_reserved_extent_alloc(fs_info, extent_key.objectid, |
|
fs_info->nodesize); |
|
return ret; |
|
} |
|
|
|
int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans, |
|
struct btrfs_root *root, u64 owner, |
|
u64 offset, u64 ram_bytes, |
|
struct btrfs_key *ins) |
|
{ |
|
struct btrfs_ref generic_ref = { 0 }; |
|
|
|
BUG_ON(root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID); |
|
|
|
btrfs_init_generic_ref(&generic_ref, BTRFS_ADD_DELAYED_EXTENT, |
|
ins->objectid, ins->offset, 0); |
|
btrfs_init_data_ref(&generic_ref, root->root_key.objectid, owner, |
|
offset, 0, false); |
|
btrfs_ref_tree_mod(root->fs_info, &generic_ref); |
|
|
|
return btrfs_add_delayed_data_ref(trans, &generic_ref, ram_bytes); |
|
} |
|
|
|
/* |
|
* this is used by the tree logging recovery code. It records that |
|
* an extent has been allocated and makes sure to clear the free |
|
* space cache bits as well |
|
*/ |
|
int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans, |
|
u64 root_objectid, u64 owner, u64 offset, |
|
struct btrfs_key *ins) |
|
{ |
|
struct btrfs_fs_info *fs_info = trans->fs_info; |
|
int ret; |
|
struct btrfs_block_group *block_group; |
|
struct btrfs_space_info *space_info; |
|
|
|
/* |
|
* Mixed block groups will exclude before processing the log so we only |
|
* need to do the exclude dance if this fs isn't mixed. |
|
*/ |
|
if (!btrfs_fs_incompat(fs_info, MIXED_GROUPS)) { |
|
ret = __exclude_logged_extent(fs_info, ins->objectid, |
|
ins->offset); |
|
if (ret) |
|
return ret; |
|
} |
|
|
|
block_group = btrfs_lookup_block_group(fs_info, ins->objectid); |
|
if (!block_group) |
|
return -EINVAL; |
|
|
|
space_info = block_group->space_info; |
|
spin_lock(&space_info->lock); |
|
spin_lock(&block_group->lock); |
|
space_info->bytes_reserved += ins->offset; |
|
block_group->reserved += ins->offset; |
|
spin_unlock(&block_group->lock); |
|
spin_unlock(&space_info->lock); |
|
|
|
ret = alloc_reserved_file_extent(trans, 0, root_objectid, 0, owner, |
|
offset, ins, 1); |
|
if (ret) |
|
btrfs_pin_extent(trans, ins->objectid, ins->offset, 1); |
|
btrfs_put_block_group(block_group); |
|
return ret; |
|
} |
|
|
|
static struct extent_buffer * |
|
btrfs_init_new_buffer(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
|
u64 bytenr, int level, u64 owner, |
|
enum btrfs_lock_nesting nest) |
|
{ |
|
struct btrfs_fs_info *fs_info = root->fs_info; |
|
struct extent_buffer *buf; |
|
|
|
buf = btrfs_find_create_tree_block(fs_info, bytenr, owner, level); |
|
if (IS_ERR(buf)) |
|
return buf; |
|
|
|
/* |
|
* Extra safety check in case the extent tree is corrupted and extent |
|
* allocator chooses to use a tree block which is already used and |
|
* locked. |
|
*/ |
|
if (buf->lock_owner == current->pid) { |
|
btrfs_err_rl(fs_info, |
|
"tree block %llu owner %llu already locked by pid=%d, extent tree corruption detected", |
|
buf->start, btrfs_header_owner(buf), current->pid); |
|
free_extent_buffer(buf); |
|
return ERR_PTR(-EUCLEAN); |
|
} |
|
|
|
/* |
|
* This needs to stay, because we could allocate a freed block from an |
|
* old tree into a new tree, so we need to make sure this new block is |
|
* set to the appropriate level and owner. |
|
*/ |
|
btrfs_set_buffer_lockdep_class(owner, buf, level); |
|
__btrfs_tree_lock(buf, nest); |
|
btrfs_clean_tree_block(buf); |
|
clear_bit(EXTENT_BUFFER_STALE, &buf->bflags); |
|
clear_bit(EXTENT_BUFFER_NO_CHECK, &buf->bflags); |
|
|
|
set_extent_buffer_uptodate(buf); |
|
|
|
memzero_extent_buffer(buf, 0, sizeof(struct btrfs_header)); |
|
btrfs_set_header_level(buf, level); |
|
btrfs_set_header_bytenr(buf, buf->start); |
|
btrfs_set_header_generation(buf, trans->transid); |
|
btrfs_set_header_backref_rev(buf, BTRFS_MIXED_BACKREF_REV); |
|
btrfs_set_header_owner(buf, owner); |
|
write_extent_buffer_fsid(buf, fs_info->fs_devices->metadata_uuid); |
|
write_extent_buffer_chunk_tree_uuid(buf, fs_info->chunk_tree_uuid); |
|
if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) { |
|
buf->log_index = root->log_transid % 2; |
|
/* |
|
* we allow two log transactions at a time, use different |
|
* EXTENT bit to differentiate dirty pages. |
|
*/ |
|
if (buf->log_index == 0) |
|
set_extent_dirty(&root->dirty_log_pages, buf->start, |
|
buf->start + buf->len - 1, GFP_NOFS); |
|
else |
|
set_extent_new(&root->dirty_log_pages, buf->start, |
|
buf->start + buf->len - 1); |
|
} else { |
|
buf->log_index = -1; |
|
set_extent_dirty(&trans->transaction->dirty_pages, buf->start, |
|
buf->start + buf->len - 1, GFP_NOFS); |
|
} |
|
/* this returns a buffer locked for blocking */ |
|
return buf; |
|
} |
|
|
|
/* |
|
* finds a free extent and does all the dirty work required for allocation |
|
* returns the tree buffer or an ERR_PTR on error. |
|
*/ |
|
struct extent_buffer *btrfs_alloc_tree_block(struct btrfs_trans_handle *trans, |
|
struct btrfs_root *root, |
|
u64 parent, u64 root_objectid, |
|
const struct btrfs_disk_key *key, |
|
int level, u64 hint, |
|
u64 empty_size, |
|
enum btrfs_lock_nesting nest) |
|
{ |
|
struct btrfs_fs_info *fs_info = root->fs_info; |
|
struct btrfs_key ins; |
|
struct btrfs_block_rsv *block_rsv; |
|
struct extent_buffer *buf; |
|
struct btrfs_delayed_extent_op *extent_op; |
|
struct btrfs_ref generic_ref = { 0 }; |
|
u64 flags = 0; |
|
int ret; |
|
u32 blocksize = fs_info->nodesize; |
|
bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA); |
|
|
|
#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS |
|
if (btrfs_is_testing(fs_info)) { |
|
buf = btrfs_init_new_buffer(trans, root, root->alloc_bytenr, |
|
level, root_objectid, nest); |
|
if (!IS_ERR(buf)) |
|
root->alloc_bytenr += blocksize; |
|
return buf; |
|
} |
|
#endif |
|
|
|
block_rsv = btrfs_use_block_rsv(trans, root, blocksize); |
|
if (IS_ERR(block_rsv)) |
|
return ERR_CAST(block_rsv); |
|
|
|
ret = btrfs_reserve_extent(root, blocksize, blocksize, blocksize, |
|
empty_size, hint, &ins, 0, 0); |
|
if (ret) |
|
goto out_unuse; |
|
|
|
buf = btrfs_init_new_buffer(trans, root, ins.objectid, level, |
|
root_objectid, nest); |
|
if (IS_ERR(buf)) { |
|
ret = PTR_ERR(buf); |
|
goto out_free_reserved; |
|
} |
|
|
|
if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) { |
|
if (parent == 0) |
|
parent = ins.objectid; |
|
flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF; |
|
} else |
|
BUG_ON(parent > 0); |
|
|
|
if (root_objectid != BTRFS_TREE_LOG_OBJECTID) { |
|
extent_op = btrfs_alloc_delayed_extent_op(); |
|
if (!extent_op) { |
|
ret = -ENOMEM; |
|
goto out_free_buf; |
|
} |
|
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; |
|
|
|
btrfs_init_generic_ref(&generic_ref, BTRFS_ADD_DELAYED_EXTENT, |
|
ins.objectid, ins.offset, parent); |
|
btrfs_init_tree_ref(&generic_ref, level, root_objectid, |
|
root->root_key.objectid, false); |
|
btrfs_ref_tree_mod(fs_info, &generic_ref); |
|
ret = btrfs_add_delayed_tree_ref(trans, &generic_ref, extent_op); |
|
if (ret) |
|
goto out_free_delayed; |
|
} |
|
return buf; |
|
|
|
out_free_delayed: |
|
btrfs_free_delayed_extent_op(extent_op); |
|
out_free_buf: |
|
btrfs_tree_unlock(buf); |
|
free_extent_buffer(buf); |
|
out_free_reserved: |
|
btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 0); |
|
out_unuse: |
|
btrfs_unuse_block_rsv(fs_info, block_rsv, blocksize); |
|
return ERR_PTR(ret); |
|
} |
|
|
|
struct walk_control { |
|
u64 refs[BTRFS_MAX_LEVEL]; |
|
u64 flags[BTRFS_MAX_LEVEL]; |
|
struct btrfs_key update_progress; |
|
struct btrfs_key drop_progress; |
|
int drop_level; |
|
int stage; |
|
int level; |
|
int shared_level; |
|
int update_ref; |
|
int keep_locks; |
|
int reada_slot; |
|
int reada_count; |
|
int restarted; |
|
}; |
|
|
|
#define DROP_REFERENCE 1 |
|
#define UPDATE_BACKREF 2 |
|
|
|
static noinline void reada_walk_down(struct btrfs_trans_handle *trans, |
|
struct btrfs_root *root, |
|
struct walk_control *wc, |
|
struct btrfs_path *path) |
|
{ |
|
struct btrfs_fs_info *fs_info = root->fs_info; |
|
u64 bytenr; |
|
u64 generation; |
|
u64 refs; |
|
u64 flags; |
|
u32 nritems; |
|
struct btrfs_key key; |
|
struct extent_buffer *eb; |
|
int ret; |
|
int slot; |
|
int nread = 0; |
|
|
|
if (path->slots[wc->level] < wc->reada_slot) { |
|
wc->reada_count = wc->reada_count * 2 / 3; |
|
wc->reada_count = max(wc->reada_count, 2); |
|
} else { |
|
wc->reada_count = wc->reada_count * 3 / 2; |
|
wc->reada_count = min_t(int, wc->reada_count, |
|
BTRFS_NODEPTRS_PER_BLOCK(fs_info)); |
|
} |
|
|
|
eb = path->nodes[wc->level]; |
|
nritems = btrfs_header_nritems(eb); |
|
|
|
for (slot = path->slots[wc->level]; slot < nritems; slot++) { |
|
if (nread >= wc->reada_count) |
|
break; |
|
|
|
cond_resched(); |
|
bytenr = btrfs_node_blockptr(eb, slot); |
|
generation = btrfs_node_ptr_generation(eb, slot); |
|
|
|
if (slot == path->slots[wc->level]) |
|
goto reada; |
|
|
|
if (wc->stage == UPDATE_BACKREF && |
|
generation <= root->root_key.offset) |
|
continue; |
|
|
|
/* We don't lock the tree block, it's OK to be racy here */ |
|
ret = btrfs_lookup_extent_info(trans, fs_info, bytenr, |
|
wc->level - 1, 1, &refs, |
|
&flags); |
|
/* We don't care about errors in readahead. */ |
|
if (ret < 0) |
|
continue; |
|
BUG_ON(refs == 0); |
|
|
|
if (wc->stage == DROP_REFERENCE) { |
|
if (refs == 1) |
|
goto reada; |
|
|
|
if (wc->level == 1 && |
|
(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)) |
|
continue; |
|
if (!wc->update_ref || |
|
generation <= root->root_key.offset) |
|
continue; |
|
btrfs_node_key_to_cpu(eb, &key, slot); |
|
ret = btrfs_comp_cpu_keys(&key, |
|
&wc->update_progress); |
|
if (ret < 0) |
|
continue; |
|
} else { |
|
if (wc->level == 1 && |
|
(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)) |
|
continue; |
|
} |
|
reada: |
|
btrfs_readahead_node_child(eb, slot); |
|
nread++; |
|
} |
|
wc->reada_slot = slot; |
|
} |
|
|
|
/* |
|
* helper to process tree block while walking down the tree. |
|
* |
|
* when wc->stage == UPDATE_BACKREF, this function updates |
|
* back refs for pointers in the block. |
|
* |
|
* NOTE: return value 1 means we should stop walking down. |
|
*/ |
|
static noinline int walk_down_proc(struct btrfs_trans_handle *trans, |
|
struct btrfs_root *root, |
|
struct btrfs_path *path, |
|
struct walk_control *wc, int lookup_info) |
|
{ |
|
struct btrfs_fs_info *fs_info = root->fs_info; |
|
int level = wc->level; |
|
struct extent_buffer *eb = path->nodes[level]; |
|
u64 flag = BTRFS_BLOCK_FLAG_FULL_BACKREF; |
|
int ret; |
|
|
|
if (wc->stage == UPDATE_BACKREF && |
|
btrfs_header_owner(eb) != root->root_key.objectid) |
|
return 1; |
|
|
|
/* |
|
* when reference count of tree block is 1, it won't increase |
|
* again. once full backref flag is set, we never clear it. |
|
*/ |
|
if (lookup_info && |
|
((wc->stage == DROP_REFERENCE && wc->refs[level] != 1) || |
|
(wc->stage == UPDATE_BACKREF && !(wc->flags[level] & flag)))) { |
|
BUG_ON(!path->locks[level]); |
|
ret = btrfs_lookup_extent_info(trans, fs_info, |
|
eb->start, level, 1, |
|
&wc->refs[level], |
|
&wc->flags[level]); |
|
BUG_ON(ret == -ENOMEM); |
|
if (ret) |
|
return ret; |
|
BUG_ON(wc->refs[level] == 0); |
|
} |
|
|
|
if (wc->stage == DROP_REFERENCE) { |
|
if (wc->refs[level] > 1) |
|
return 1; |
|
|
|
if (path->locks[level] && !wc->keep_locks) { |
|
btrfs_tree_unlock_rw(eb, path->locks[level]); |
|
path->locks[level] = 0; |
|
} |
|
return 0; |
|
} |
|
|
|
/* wc->stage == UPDATE_BACKREF */ |
|
if (!(wc->flags[level] & flag)) { |
|
BUG_ON(!path->locks[level]); |
|
ret = btrfs_inc_ref(trans, root, eb, 1); |
|
BUG_ON(ret); /* -ENOMEM */ |
|
ret = btrfs_dec_ref(trans, root, eb, 0); |
|
BUG_ON(ret); /* -ENOMEM */ |
|
ret = btrfs_set_disk_extent_flags(trans, eb, flag, |
|
btrfs_header_level(eb), 0); |
|
BUG_ON(ret); /* -ENOMEM */ |
|
wc->flags[level] |= flag; |
|
} |
|
|
|
/* |
|
* the block is shared by multiple trees, so it's not good to |
|
* keep the tree lock |
|
*/ |
|
if (path->locks[level] && level > 0) { |
|
btrfs_tree_unlock_rw(eb, path->locks[level]); |
|
path->locks[level] = 0; |
|
} |
|
return 0; |
|
} |
|
|
|
/* |
|
* This is used to verify a ref exists for this root to deal with a bug where we |
|
* would have a drop_progress key that hadn't been updated properly. |
|
*/ |
|
static int check_ref_exists(struct btrfs_trans_handle *trans, |
|
struct btrfs_root *root, u64 bytenr, u64 parent, |
|
int level) |
|
{ |
|
struct btrfs_path *path; |
|
struct btrfs_extent_inline_ref *iref; |
|
int ret; |
|
|
|
path = btrfs_alloc_path(); |
|
if (!path) |
|
return -ENOMEM; |
|
|
|
ret = lookup_extent_backref(trans, path, &iref, bytenr, |
|
root->fs_info->nodesize, parent, |
|
root->root_key.objectid, level, 0); |
|
btrfs_free_path(path); |
|
if (ret == -ENOENT) |
|
return 0; |
|
if (ret < 0) |
|
return ret; |
|
return 1; |
|
} |
|
|
|
/* |
|
* helper to process tree block pointer. |
|
* |
|
* when wc->stage == DROP_REFERENCE, this function checks |
|
* reference count of the block pointed to. if the block |
|
* is shared and we need update back refs for the subtree |
|
* rooted at the block, this function changes wc->stage to |
|
* UPDATE_BACKREF. if the block is shared and there is no |
|
* need to update back, this function drops the reference |
|
* to the block. |
|
* |
|
* NOTE: return value 1 means we should stop walking down. |
|
*/ |
|
static noinline int do_walk_down(struct btrfs_trans_handle *trans, |
|
struct btrfs_root *root, |
|
struct btrfs_path *path, |
|
struct walk_control *wc, int *lookup_info) |
|
{ |
|
struct btrfs_fs_info *fs_info = root->fs_info; |
|
u64 bytenr; |
|
u64 generation; |
|
u64 parent; |
|
struct btrfs_key key; |
|
struct btrfs_key first_key; |
|
struct btrfs_ref ref = { 0 }; |
|
struct extent_buffer *next; |
|
int level = wc->level; |
|
int reada = 0; |
|
int ret = 0; |
|
bool need_account = false; |
|
|
|
generation = btrfs_node_ptr_generation(path->nodes[level], |
|
path->slots[level]); |
|
/* |
|
* if the lower level block was created before the snapshot |
|
* was created, we know there is no need to update back refs |
|
* for the subtree |
|
*/ |
|
if (wc->stage == UPDATE_BACKREF && |
|
generation <= root->root_key.offset) { |
|
*lookup_info = 1; |
|
return 1; |
|
} |
|
|
|
bytenr = btrfs_node_blockptr(path->nodes[level], path->slots[level]); |
|
btrfs_node_key_to_cpu(path->nodes[level], &first_key, |
|
path->slots[level]); |
|
|
|
next = find_extent_buffer(fs_info, bytenr); |
|
if (!next) { |
|
next = btrfs_find_create_tree_block(fs_info, bytenr, |
|
root->root_key.objectid, level - 1); |
|
if (IS_ERR(next)) |
|
return PTR_ERR(next); |
|
reada = 1; |
|
} |
|
btrfs_tree_lock(next); |
|
|
|
ret = btrfs_lookup_extent_info(trans, fs_info, bytenr, level - 1, 1, |
|
&wc->refs[level - 1], |
|
&wc->flags[level - 1]); |
|
if (ret < 0) |
|
goto out_unlock; |
|
|
|
if (unlikely(wc->refs[level - 1] == 0)) { |
|
btrfs_err(fs_info, "Missing references."); |
|
ret = -EIO; |
|
goto out_unlock; |
|
} |
|
*lookup_info = 0; |
|
|
|
if (wc->stage == DROP_REFERENCE) { |
|
if (wc->refs[level - 1] > 1) { |
|
need_account = true; |
|
if (level == 1 && |
|
(wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF)) |
|
goto skip; |
|
|
|
if (!wc->update_ref || |
|
generation <= root->root_key.offset) |
|
goto skip; |
|
|
|
btrfs_node_key_to_cpu(path->nodes[level], &key, |
|
path->slots[level]); |
|
ret = btrfs_comp_cpu_keys(&key, &wc->update_progress); |
|
if (ret < 0) |
|
goto skip; |
|
|
|
wc->stage = UPDATE_BACKREF; |
|
wc->shared_level = level - 1; |
|
} |
|
} else { |
|
if (level == 1 && |
|
(wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF)) |
|
goto skip; |
|
} |
|
|
|
if (!btrfs_buffer_uptodate(next, generation, 0)) { |
|
btrfs_tree_unlock(next); |
|
free_extent_buffer(next); |
|
next = NULL; |
|
*lookup_info = 1; |
|
} |
|
|
|
if (!next) { |
|
if (reada && level == 1) |
|
reada_walk_down(trans, root, wc, path); |
|
next = read_tree_block(fs_info, bytenr, root->root_key.objectid, |
|
generation, level - 1, &first_key); |
|
if (IS_ERR(next)) { |
|
return PTR_ERR(next); |
|
} else if (!extent_buffer_uptodate(next)) { |
|
free_extent_buffer(next); |
|
return -EIO; |
|
} |
|
btrfs_tree_lock(next); |
|
} |
|
|
|
level--; |
|
ASSERT(level == btrfs_header_level(next)); |
|
if (level != btrfs_header_level(next)) { |
|
btrfs_err(root->fs_info, "mismatched level"); |
|
ret = -EIO; |
|
goto out_unlock; |
|
} |
|
path->nodes[level] = next; |
|
path->slots[level] = 0; |
|
path->locks[level] = BTRFS_WRITE_LOCK; |
|
wc->level = level; |
|
if (wc->level == 1) |
|
wc->reada_slot = 0; |
|
return 0; |
|
skip: |
|
wc->refs[level - 1] = 0; |
|
wc->flags[level - 1] = 0; |
|
if (wc->stage == DROP_REFERENCE) { |
|
if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) { |
|
parent = path->nodes[level]->start; |
|
} else { |
|
ASSERT(root->root_key.objectid == |
|
btrfs_header_owner(path->nodes[level])); |
|
if (root->root_key.objectid != |
|
btrfs_header_owner(path->nodes[level])) { |
|
btrfs_err(root->fs_info, |
|
"mismatched block owner"); |
|
ret = -EIO; |
|
goto out_unlock; |
|
} |
|
parent = 0; |
|
} |
|
|
|
/* |
|
* If we had a drop_progress we need to verify the refs are set |
|
* as expected. If we find our ref then we know that from here |
|
* on out everything should be correct, and we can clear the |
|
* ->restarted flag. |
|
*/ |
|
if (wc->restarted) { |
|
ret = check_ref_exists(trans, root, bytenr, parent, |
|
level - 1); |
|
if (ret < 0) |
|
goto out_unlock; |
|
if (ret == 0) |
|
goto no_delete; |
|
ret = 0; |
|
wc->restarted = 0; |
|
} |
|
|
|
/* |
|
* Reloc tree doesn't contribute to qgroup numbers, and we have |
|
* already accounted them at merge time (replace_path), |
|
* thus we could skip expensive subtree trace here. |
|
*/ |
|
if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID && |
|
need_account) { |
|
ret = btrfs_qgroup_trace_subtree(trans, next, |
|
generation, level - 1); |
|
if (ret) { |
|
btrfs_err_rl(fs_info, |
|
"Error %d accounting shared subtree. Quota is out of sync, rescan required.", |
|
ret); |
|
} |
|
} |
|
|
|
/* |
|
* We need to update the next key in our walk control so we can |
|
* update the drop_progress key accordingly. We don't care if |
|
* find_next_key doesn't find a key because that means we're at |
|
* the end and are going to clean up now. |
|
*/ |
|
wc->drop_level = level; |
|
find_next_key(path, level, &wc->drop_progress); |
|
|
|
btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, bytenr, |
|
fs_info->nodesize, parent); |
|
btrfs_init_tree_ref(&ref, level - 1, root->root_key.objectid, |
|
0, false); |
|
ret = btrfs_free_extent(trans, &ref); |
|
if (ret) |
|
goto out_unlock; |
|
} |
|
no_delete: |
|
*lookup_info = 1; |
|
ret = 1; |
|
|
|
out_unlock: |
|
btrfs_tree_unlock(next); |
|
free_extent_buffer(next); |
|
|
|
return ret; |
|
} |
|
|
|
/* |
|
* helper to process tree block while walking up the tree. |
|
* |
|
* when wc->stage == DROP_REFERENCE, this function drops |
|
* reference count on the block. |
|
* |
|
* when wc->stage == UPDATE_BACKREF, this function changes |
|
* wc->stage back to DROP_REFERENCE if we changed wc->stage |
|
* to UPDATE_BACKREF previously while processing the block. |
|
* |
|
* NOTE: return value 1 means we should stop walking up. |
|
*/ |
|
static noinline int walk_up_proc(struct btrfs_trans_handle *trans, |
|
struct btrfs_root *root, |
|
struct btrfs_path *path, |
|
struct walk_control *wc) |
|
{ |
|
struct btrfs_fs_info *fs_info = root->fs_info; |
|
int ret; |
|
int level = wc->level; |
|
struct extent_buffer *eb = path->nodes[level]; |
|
u64 parent = 0; |
|
|
|
if (wc->stage == UPDATE_BACKREF) { |
|
BUG_ON(wc->shared_level < level); |
|
if (level < wc->shared_level) |
|
goto out; |
|
|
|
ret = find_next_key(path, level + 1, &wc->update_progress); |
|
if (ret > 0) |
|
wc->update_ref = 0; |
|
|
|
wc->stage = DROP_REFERENCE; |
|
wc->shared_level = -1; |
|
path->slots[level] = 0; |
|
|
|
/* |
|
* check reference count again if the block isn't locked. |
|
* we should start walking down the tree again if reference |
|
* count is one. |
|
*/ |
|
if (!path->locks[level]) { |
|
BUG_ON(level == 0); |
|
btrfs_tree_lock(eb); |
|
path->locks[level] = BTRFS_WRITE_LOCK; |
|
|
|
ret = btrfs_lookup_extent_info(trans, fs_info, |
|
eb->start, level, 1, |
|
&wc->refs[level], |
|
&wc->flags[level]); |
|
if (ret < 0) { |
|
btrfs_tree_unlock_rw(eb, path->locks[level]); |
|
path->locks[level] = 0; |
|
return ret; |
|
} |
|
BUG_ON(wc->refs[level] == 0); |
|
if (wc->refs[level] == 1) { |
|
btrfs_tree_unlock_rw(eb, path->locks[level]); |
|
path->locks[level] = 0; |
|
return 1; |
|
} |
|
} |
|
} |
|
|
|
/* wc->stage == DROP_REFERENCE */ |
|
BUG_ON(wc->refs[level] > 1 && !path->locks[level]); |
|
|
|
if (wc->refs[level] == 1) { |
|
if (level == 0) { |
|
if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) |
|
ret = btrfs_dec_ref(trans, root, eb, 1); |
|
else |
|
ret = btrfs_dec_ref(trans, root, eb, 0); |
|
BUG_ON(ret); /* -ENOMEM */ |
|
if (is_fstree(root->root_key.objectid)) { |
|
ret = btrfs_qgroup_trace_leaf_items(trans, eb); |
|
if (ret) { |
|
btrfs_err_rl(fs_info, |
|
"error %d accounting leaf items, quota is out of sync, rescan required", |
|
ret); |
|
} |
|
} |
|
} |
|
/* make block locked assertion in btrfs_clean_tree_block happy */ |
|
if (!path->locks[level] && |
|
btrfs_header_generation(eb) == trans->transid) { |
|
btrfs_tree_lock(eb); |
|
path->locks[level] = BTRFS_WRITE_LOCK; |
|
} |
|
btrfs_clean_tree_block(eb); |
|
} |
|
|
|
if (eb == root->node) { |
|
if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) |
|
parent = eb->start; |
|
else if (root->root_key.objectid != btrfs_header_owner(eb)) |
|
goto owner_mismatch; |
|
} else { |
|
if (wc->flags[level + 1] & BTRFS_BLOCK_FLAG_FULL_BACKREF) |
|
parent = path->nodes[level + 1]->start; |
|
else if (root->root_key.objectid != |
|
btrfs_header_owner(path->nodes[level + 1])) |
|
goto owner_mismatch; |
|
} |
|
|
|
btrfs_free_tree_block(trans, btrfs_root_id(root), eb, parent, |
|
wc->refs[level] == 1); |
|
out: |
|
wc->refs[level] = 0; |
|
wc->flags[level] = 0; |
|
return 0; |
|
|
|
owner_mismatch: |
|
btrfs_err_rl(fs_info, "unexpected tree owner, have %llu expect %llu", |
|
btrfs_header_owner(eb), root->root_key.objectid); |
|
return -EUCLEAN; |
|
} |
|
|
|
static noinline int walk_down_tree(struct btrfs_trans_handle *trans, |
|
struct btrfs_root *root, |
|
struct btrfs_path *path, |
|
struct walk_control *wc) |
|
{ |
|
int level = wc->level; |
|
int lookup_info = 1; |
|
int ret; |
|
|
|
while (level >= 0) { |
|
ret = walk_down_proc(trans, root, path, wc, lookup_info); |
|
if (ret > 0) |
|
break; |
|
|
|
if (level == 0) |
|
break; |
|
|
|
if (path->slots[level] >= |
|
btrfs_header_nritems(path->nodes[level])) |
|
break; |
|
|
|
ret = do_walk_down(trans, root, path, wc, &lookup_info); |
|
if (ret > 0) { |
|
path->slots[level]++; |
|
continue; |
|
} else if (ret < 0) |
|
return ret; |
|
level = wc->level; |
|
} |
|
return 0; |
|
} |
|
|
|
static noinline int walk_up_tree(struct btrfs_trans_handle *trans, |
|
struct btrfs_root *root, |
|
struct btrfs_path *path, |
|
struct walk_control *wc, int max_level) |
|
{ |
|
int level = wc->level; |
|
int ret; |
|
|
|
path->slots[level] = btrfs_header_nritems(path->nodes[level]); |
|
while (level < max_level && path->nodes[level]) { |
|
wc->level = level; |
|
if (path->slots[level] + 1 < |
|
btrfs_header_nritems(path->nodes[level])) { |
|
path->slots[level]++; |
|
return 0; |
|
} else { |
|
ret = walk_up_proc(trans, root, path, wc); |
|
if (ret > 0) |
|
return 0; |
|
if (ret < 0) |
|
return ret; |
|
|
|
if (path->locks[level]) { |
|
btrfs_tree_unlock_rw(path->nodes[level], |
|
path->locks[level]); |
|
path->locks[level] = 0; |
|
} |
|
free_extent_buffer(path->nodes[level]); |
|
path->nodes[level] = NULL; |
|
level++; |
|
} |
|
} |
|
return 1; |
|
} |
|
|
|
/* |
|
* drop a subvolume tree. |
|
* |
|
* this function traverses the tree freeing any blocks that only |
|
* referenced by the tree. |
|
* |
|
* when a shared tree block is found. this function decreases its |
|
* reference count by one. if update_ref is true, this function |
|
* also make sure backrefs for the shared block and all lower level |
|
* blocks are properly updated. |
|
* |
|
* If called with for_reloc == 0, may exit early with -EAGAIN |
|
*/ |
|
int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref, int for_reloc) |
|
{ |
|
struct btrfs_fs_info *fs_info = root->fs_info; |
|
struct btrfs_path *path; |
|
struct btrfs_trans_handle *trans; |
|
struct btrfs_root *tree_root = fs_info->tree_root; |
|
struct btrfs_root_item *root_item = &root->root_item; |
|
struct walk_control *wc; |
|
struct btrfs_key key; |
|
int err = 0; |
|
int ret; |
|
int level; |
|
bool root_dropped = false; |
|
|
|
btrfs_debug(fs_info, "Drop subvolume %llu", root->root_key.objectid); |
|
|
|
path = btrfs_alloc_path(); |
|
if (!path) { |
|
err = -ENOMEM; |
|
goto out; |
|
} |
|
|
|
wc = kzalloc(sizeof(*wc), GFP_NOFS); |
|
if (!wc) { |
|
btrfs_free_path(path); |
|
err = -ENOMEM; |
|
goto out; |
|
} |
|
|
|
/* |
|
* Use join to avoid potential EINTR from transaction start. See |
|
* wait_reserve_ticket and the whole reservation callchain. |
|
*/ |
|
if (for_reloc) |
|
trans = btrfs_join_transaction(tree_root); |
|
else |
|
trans = btrfs_start_transaction(tree_root, 0); |
|
if (IS_ERR(trans)) { |
|
err = PTR_ERR(trans); |
|
goto out_free; |
|
} |
|
|
|
err = btrfs_run_delayed_items(trans); |
|
if (err) |
|
goto out_end_trans; |
|
|
|
/* |
|
* This will help us catch people modifying the fs tree while we're |
|
* dropping it. It is unsafe to mess with the fs tree while it's being |
|
* dropped as we unlock the root node and parent nodes as we walk down |
|
* the tree, assuming nothing will change. If something does change |
|
* then we'll have stale information and drop references to blocks we've |
|
* already dropped. |
|
*/ |
|
set_bit(BTRFS_ROOT_DELETING, &root->state); |
|
if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) { |
|
level = btrfs_header_level(root->node); |
|
path->nodes[level] = btrfs_lock_root_node(root); |
|
path->slots[level] = 0; |
|
path->locks[level] = BTRFS_WRITE_LOCK; |
|
memset(&wc->update_progress, 0, |
|
sizeof(wc->update_progress)); |
|
} else { |
|
btrfs_disk_key_to_cpu(&key, &root_item->drop_progress); |
|
memcpy(&wc->update_progress, &key, |
|
sizeof(wc->update_progress)); |
|
|
|
level = btrfs_root_drop_level(root_item); |
|
BUG_ON(level == 0); |
|
path->lowest_level = level; |
|
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
|
path->lowest_level = 0; |
|
if (ret < 0) { |
|
err = ret; |
|
goto out_end_trans; |
|
} |
|
WARN_ON(ret > 0); |
|
|
|
/* |
|
* unlock our path, this is safe because only this |
|
* function is allowed to delete this snapshot |
|
*/ |
|
btrfs_unlock_up_safe(path, 0); |
|
|
|
level = btrfs_header_level(root->node); |
|
while (1) { |
|
btrfs_tree_lock(path->nodes[level]); |
|
path->locks[level] = BTRFS_WRITE_LOCK; |
|
|
|
ret = btrfs_lookup_extent_info(trans, fs_info, |
|
path->nodes[level]->start, |
|
level, 1, &wc->refs[level], |
|
&wc->flags[level]); |
|
if (ret < 0) { |
|
err = ret; |
|
goto out_end_trans; |
|
} |
|
BUG_ON(wc->refs[level] == 0); |
|
|
|
if (level == btrfs_root_drop_level(root_item)) |
|
break; |
|
|
|
btrfs_tree_unlock(path->nodes[level]); |
|
path->locks[level] = 0; |
|
WARN_ON(wc->refs[level] != 1); |
|
level--; |
|
} |
|
} |
|
|
|
wc->restarted = test_bit(BTRFS_ROOT_DEAD_TREE, &root->state); |
|
wc->level = level; |
|
wc->shared_level = -1; |
|
wc->stage = DROP_REFERENCE; |
|
wc->update_ref = update_ref; |
|
wc->keep_locks = 0; |
|
wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(fs_info); |
|
|
|
while (1) { |
|
|
|
ret = walk_down_tree(trans, root, path, wc); |
|
if (ret < 0) { |
|
err = ret; |
|
break; |
|
} |
|
|
|
ret = walk_up_tree(trans, root, path, wc, BTRFS_MAX_LEVEL); |
|
if (ret < 0) { |
|
err = ret; |
|
break; |
|
} |
|
|
|
if (ret > 0) { |
|
BUG_ON(wc->stage != DROP_REFERENCE); |
|
break; |
|
} |
|
|
|
if (wc->stage == DROP_REFERENCE) { |
|
wc->drop_level = wc->level; |
|
btrfs_node_key_to_cpu(path->nodes[wc->drop_level], |
|
&wc->drop_progress, |
|
path->slots[wc->drop_level]); |
|
} |
|
btrfs_cpu_key_to_disk(&root_item->drop_progress, |
|
&wc->drop_progress); |
|
btrfs_set_root_drop_level(root_item, wc->drop_level); |
|
|
|
BUG_ON(wc->level == 0); |
|
if (btrfs_should_end_transaction(trans) || |
|
(!for_reloc && btrfs_need_cleaner_sleep(fs_info))) { |
|
ret = btrfs_update_root(trans, tree_root, |
|
&root->root_key, |
|
root_item); |
|
if (ret) { |
|
btrfs_abort_transaction(trans, ret); |
|
err = ret; |
|
goto out_end_trans; |
|
} |
|
|
|
btrfs_end_transaction_throttle(trans); |
|
if (!for_reloc && btrfs_need_cleaner_sleep(fs_info)) { |
|
btrfs_debug(fs_info, |
|
"drop snapshot early exit"); |
|
err = -EAGAIN; |
|
goto out_free; |
|
} |
|
|
|
/* |
|
* Use join to avoid potential EINTR from transaction |
|
* start. See wait_reserve_ticket and the whole |
|
* reservation callchain. |
|
*/ |
|
if (for_reloc) |
|
trans = btrfs_join_transaction(tree_root); |
|
else |
|
trans = btrfs_start_transaction(tree_root, 0); |
|
if (IS_ERR(trans)) { |
|
err = PTR_ERR(trans); |
|
goto out_free; |
|
} |
|
} |
|
} |
|
btrfs_release_path(path); |
|
if (err) |
|
goto out_end_trans; |
|
|
|
ret = btrfs_del_root(trans, &root->root_key); |
|
if (ret) { |
|
btrfs_abort_transaction(trans, ret); |
|
err = ret; |
|
goto out_end_trans; |
|
} |
|
|
|
if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) { |
|
ret = btrfs_find_root(tree_root, &root->root_key, path, |
|
NULL, NULL); |
|
if (ret < 0) { |
|
btrfs_abort_transaction(trans, ret); |
|
err = ret; |
|
goto out_end_trans; |
|
} else if (ret > 0) { |
|
/* if we fail to delete the orphan item this time |
|
* around, it'll get picked up the next time. |
|
* |
|
* The most common failure here is just -ENOENT. |
|
*/ |
|
btrfs_del_orphan_item(trans, tree_root, |
|
root->root_key.objectid); |
|
} |
|
} |
|
|
|
/* |
|
* This subvolume is going to be completely dropped, and won't be |
|
* recorded as dirty roots, thus pertrans meta rsv will not be freed at |
|
* commit transaction time. So free it here manually. |
|
*/ |
|
btrfs_qgroup_convert_reserved_meta(root, INT_MAX); |
|
btrfs_qgroup_free_meta_all_pertrans(root); |
|
|
|
if (test_bit(BTRFS_ROOT_IN_RADIX, &root->state)) |
|
btrfs_add_dropped_root(trans, root); |
|
else |
|
btrfs_put_root(root); |
|
root_dropped = true; |
|
out_end_trans: |
|
btrfs_end_transaction_throttle(trans); |
|
out_free: |
|
kfree(wc); |
|
btrfs_free_path(path); |
|
out: |
|
/* |
|
* So if we need to stop dropping the snapshot for whatever reason we |
|
* need to make sure to add it back to the dead root list so that we |
|
* keep trying to do the work later. This also cleans up roots if we |
|
* don't have it in the radix (like when we recover after a power fail |
|
* or unmount) so we don't leak memory. |
|
*/ |
|
if (!for_reloc && !root_dropped) |
|
btrfs_add_dead_root(root); |
|
return err; |
|
} |
|
|
|
/* |
|
* drop subtree rooted at tree block 'node'. |
|
* |
|
* NOTE: this function will unlock and release tree block 'node' |
|
* only used by relocation code |
|
*/ |
|
int btrfs_drop_subtree(struct btrfs_trans_handle *trans, |
|
struct btrfs_root *root, |
|
struct extent_buffer *node, |
|
struct extent_buffer *parent) |
|
{ |
|
struct btrfs_fs_info *fs_info = root->fs_info; |
|
struct btrfs_path *path; |
|
struct walk_control *wc; |
|
int level; |
|
int parent_level; |
|
int ret = 0; |
|
int wret; |
|
|
|
BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID); |
|
|
|
path = btrfs_alloc_path(); |
|
if (!path) |
|
return -ENOMEM; |
|
|
|
wc = kzalloc(sizeof(*wc), GFP_NOFS); |
|
if (!wc) { |
|
btrfs_free_path(path); |
|
return -ENOMEM; |
|
} |
|
|
|
btrfs_assert_tree_write_locked(parent); |
|
parent_level = btrfs_header_level(parent); |
|
atomic_inc(&parent->refs); |
|
path->nodes[parent_level] = parent; |
|
path->slots[parent_level] = btrfs_header_nritems(parent); |
|
|
|
btrfs_assert_tree_write_locked(node); |
|
level = btrfs_header_level(node); |
|
path->nodes[level] = node; |
|
path->slots[level] = 0; |
|
path->locks[level] = BTRFS_WRITE_LOCK; |
|
|
|
wc->refs[parent_level] = 1; |
|
wc->flags[parent_level] = BTRFS_BLOCK_FLAG_FULL_BACKREF; |
|
wc->level = level; |
|
wc->shared_level = -1; |
|
wc->stage = DROP_REFERENCE; |
|
wc->update_ref = 0; |
|
wc->keep_locks = 1; |
|
wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(fs_info); |
|
|
|
while (1) { |
|
wret = walk_down_tree(trans, root, path, wc); |
|
if (wret < 0) { |
|
ret = wret; |
|
break; |
|
} |
|
|
|
wret = walk_up_tree(trans, root, path, wc, parent_level); |
|
if (wret < 0) |
|
ret = wret; |
|
if (wret != 0) |
|
break; |
|
} |
|
|
|
kfree(wc); |
|
btrfs_free_path(path); |
|
return ret; |
|
} |
|
|
|
/* |
|
* helper to account the unused space of all the readonly block group in the |
|
* space_info. takes mirrors into account. |
|
*/ |
|
u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo) |
|
{ |
|
struct btrfs_block_group *block_group; |
|
u64 free_bytes = 0; |
|
int factor; |
|
|
|
/* It's df, we don't care if it's racy */ |
|
if (list_empty(&sinfo->ro_bgs)) |
|
return 0; |
|
|
|
spin_lock(&sinfo->lock); |
|
list_for_each_entry(block_group, &sinfo->ro_bgs, ro_list) { |
|
spin_lock(&block_group->lock); |
|
|
|
if (!block_group->ro) { |
|
spin_unlock(&block_group->lock); |
|
continue; |
|
} |
|
|
|
factor = btrfs_bg_type_to_factor(block_group->flags); |
|
free_bytes += (block_group->length - |
|
block_group->used) * factor; |
|
|
|
spin_unlock(&block_group->lock); |
|
} |
|
spin_unlock(&sinfo->lock); |
|
|
|
return free_bytes; |
|
} |
|
|
|
int btrfs_error_unpin_extent_range(struct btrfs_fs_info *fs_info, |
|
u64 start, u64 end) |
|
{ |
|
return unpin_extent_range(fs_info, start, end, false); |
|
} |
|
|
|
/* |
|
* It used to be that old block groups would be left around forever. |
|
* Iterating over them would be enough to trim unused space. Since we |
|
* now automatically remove them, we also need to iterate over unallocated |
|
* space. |
|
* |
|
* We don't want a transaction for this since the discard may take a |
|
* substantial amount of time. We don't require that a transaction be |
|
* running, but we do need to take a running transaction into account |
|
* to ensure that we're not discarding chunks that were released or |
|
* allocated in the current transaction. |
|
* |
|
* Holding the chunks lock will prevent other threads from allocating |
|
* or releasing chunks, but it won't prevent a running transaction |
|
* from committing and releasing the memory that the pending chunks |
|
* list head uses. For that, we need to take a reference to the |
|
* transaction and hold the commit root sem. We only need to hold |
|
* it while performing the free space search since we have already |
|
* held back allocations. |
|
*/ |
|
static int btrfs_trim_free_extents(struct btrfs_device *device, u64 *trimmed) |
|
{ |
|
u64 start = SZ_1M, len = 0, end = 0; |
|
int ret; |
|
|
|
*trimmed = 0; |
|
|
|
/* Discard not supported = nothing to do. */ |
|
if (!blk_queue_discard(bdev_get_queue(device->bdev))) |
|
return 0; |
|
|
|
/* Not writable = nothing to do. */ |
|
if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) |
|
return 0; |
|
|
|
/* No free space = nothing to do. */ |
|
if (device->total_bytes <= device->bytes_used) |
|
return 0; |
|
|
|
ret = 0; |
|
|
|
while (1) { |
|
struct btrfs_fs_info *fs_info = device->fs_info; |
|
u64 bytes; |
|
|
|
ret = mutex_lock_interruptible(&fs_info->chunk_mutex); |
|
if (ret) |
|
break; |
|
|
|
find_first_clear_extent_bit(&device->alloc_state, start, |
|
&start, &end, |
|
CHUNK_TRIMMED | CHUNK_ALLOCATED); |
|
|
|
/* Check if there are any CHUNK_* bits left */ |
|
if (start > device->total_bytes) { |
|
WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG)); |
|
btrfs_warn_in_rcu(fs_info, |
|
"ignoring attempt to trim beyond device size: offset %llu length %llu device %s device size %llu", |
|
start, end - start + 1, |
|
rcu_str_deref(device->name), |
|
device->total_bytes); |
|
mutex_unlock(&fs_info->chunk_mutex); |
|
ret = 0; |
|
break; |
|
} |
|
|
|
/* Ensure we skip the reserved area in the first 1M */ |
|
start = max_t(u64, start, SZ_1M); |
|
|
|
/* |
|
* If find_first_clear_extent_bit find a range that spans the |
|
* end of the device it will set end to -1, in this case it's up |
|
* to the caller to trim the value to the size of the device. |
|
*/ |
|
end = min(end, device->total_bytes - 1); |
|
|
|
len = end - start + 1; |
|
|
|
/* We didn't find any extents */ |
|
if (!len) { |
|
mutex_unlock(&fs_info->chunk_mutex); |
|
ret = 0; |
|
break; |
|
} |
|
|
|
ret = btrfs_issue_discard(device->bdev, start, len, |
|
&bytes); |
|
if (!ret) |
|
set_extent_bits(&device->alloc_state, start, |
|
start + bytes - 1, |
|
CHUNK_TRIMMED); |
|
mutex_unlock(&fs_info->chunk_mutex); |
|
|
|
if (ret) |
|
break; |
|
|
|
start += len; |
|
*trimmed += bytes; |
|
|
|
if (fatal_signal_pending(current)) { |
|
ret = -ERESTARTSYS; |
|
break; |
|
} |
|
|
|
cond_resched(); |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
/* |
|
* Trim the whole filesystem by: |
|
* 1) trimming the free space in each block group |
|
* 2) trimming the unallocated space on each device |
|
* |
|
* This will also continue trimming even if a block group or device encounters |
|
* an error. The return value will be the last error, or 0 if nothing bad |
|
* happens. |
|
*/ |
|
int btrfs_trim_fs(struct btrfs_fs_info *fs_info, struct fstrim_range *range) |
|
{ |
|
struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; |
|
struct btrfs_block_group *cache = NULL; |
|
struct btrfs_device *device; |
|
u64 group_trimmed; |
|
u64 range_end = U64_MAX; |
|
u64 start; |
|
u64 end; |
|
u64 trimmed = 0; |
|
u64 bg_failed = 0; |
|
u64 dev_failed = 0; |
|
int bg_ret = 0; |
|
int dev_ret = 0; |
|
int ret = 0; |
|
|
|
if (range->start == U64_MAX) |
|
return -EINVAL; |
|
|
|
/* |
|
* Check range overflow if range->len is set. |
|
* The default range->len is U64_MAX. |
|
*/ |
|
if (range->len != U64_MAX && |
|
check_add_overflow(range->start, range->len, &range_end)) |
|
return -EINVAL; |
|
|
|
cache = btrfs_lookup_first_block_group(fs_info, range->start); |
|
for (; cache; cache = btrfs_next_block_group(cache)) { |
|
if (cache->start >= range_end) { |
|
btrfs_put_block_group(cache); |
|
break; |
|
} |
|
|
|
start = max(range->start, cache->start); |
|
end = min(range_end, cache->start + cache->length); |
|
|
|
if (end - start >= range->minlen) { |
|
if (!btrfs_block_group_done(cache)) { |
|
ret = btrfs_cache_block_group(cache, 0); |
|
if (ret) { |
|
bg_failed++; |
|
bg_ret = ret; |
|
continue; |
|
} |
|
ret = btrfs_wait_block_group_cache_done(cache); |
|
if (ret) { |
|
bg_failed++; |
|
bg_ret = ret; |
|
continue; |
|
} |
|
} |
|
ret = btrfs_trim_block_group(cache, |
|
&group_trimmed, |
|
start, |
|
end, |
|
range->minlen); |
|
|
|
trimmed += group_trimmed; |
|
if (ret) { |
|
bg_failed++; |
|
bg_ret = ret; |
|
continue; |
|
} |
|
} |
|
} |
|
|
|
if (bg_failed) |
|
btrfs_warn(fs_info, |
|
"failed to trim %llu block group(s), last error %d", |
|
bg_failed, bg_ret); |
|
|
|
mutex_lock(&fs_devices->device_list_mutex); |
|
list_for_each_entry(device, &fs_devices->devices, dev_list) { |
|
if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) |
|
continue; |
|
|
|
ret = btrfs_trim_free_extents(device, &group_trimmed); |
|
if (ret) { |
|
dev_failed++; |
|
dev_ret = ret; |
|
break; |
|
} |
|
|
|
trimmed += group_trimmed; |
|
} |
|
mutex_unlock(&fs_devices->device_list_mutex); |
|
|
|
if (dev_failed) |
|
btrfs_warn(fs_info, |
|
"failed to trim %llu device(s), last error %d", |
|
dev_failed, dev_ret); |
|
range->len = trimmed; |
|
if (bg_ret) |
|
return bg_ret; |
|
return dev_ret; |
|
}
|
|
|