linux/fs/btrfs/extent-tree.h
Filipe Manana bb3868033a btrfs: do not BUG_ON() when freeing tree block after error
When freeing a tree block, at btrfs_free_tree_block(), if we fail to
create a delayed reference we don't deal with the error and just do a
BUG_ON(). The error most likely to happen is -ENOMEM, and we have a
comment mentioning that only -ENOMEM can happen, but that is not true,
because in case qgroups are enabled any error returned from
btrfs_qgroup_trace_extent_post() (can be -EUCLEAN or anything returned
from btrfs_search_slot() for example) can be propagated back to
btrfs_free_tree_block().

So stop doing a BUG_ON() and return the error to the callers and make
them abort the transaction to prevent leaking space. Syzbot was
triggering this, likely due to memory allocation failure injection.

Reported-by: syzbot+a306f914b4d01b3958fe@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/000000000000fcba1e05e998263c@google.com/
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:26 +02:00

168 lines
5.3 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef BTRFS_EXTENT_TREE_H
#define BTRFS_EXTENT_TREE_H
#include <linux/types.h>
#include "misc.h"
#include "block-group.h"
#include "locking.h"
struct extent_buffer;
struct btrfs_free_cluster;
struct btrfs_fs_info;
struct btrfs_root;
struct btrfs_path;
struct btrfs_ref;
struct btrfs_disk_key;
struct btrfs_delayed_ref_head;
struct btrfs_delayed_ref_root;
struct btrfs_extent_inline_ref;
enum btrfs_extent_allocation_policy {
BTRFS_EXTENT_ALLOC_CLUSTERED,
BTRFS_EXTENT_ALLOC_ZONED,
};
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;
/*
* Set to true if we're retrying the allocation on this block group
* after waiting for caching progress, this is so that we retry only
* once before moving on to another block group.
*/
bool retry_uncached;
/* 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;
/* Whether or not the allocator is currently following a hint */
bool hinted;
/* Size class of block groups to prefer in early loops */
enum btrfs_block_group_size_class size_class;
};
enum btrfs_inline_ref_type {
BTRFS_REF_TYPE_INVALID,
BTRFS_REF_TYPE_BLOCK,
BTRFS_REF_TYPE_DATA,
BTRFS_REF_TYPE_ANY,
};
int btrfs_get_extent_inline_ref_type(const struct extent_buffer *eb,
struct btrfs_extent_inline_ref *iref,
enum btrfs_inline_ref_type is_data);
u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset);
int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans, u64 min_bytes);
u64 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 btrfs_lookup_data_extent(struct btrfs_fs_info *fs_info, u64 start, u64 len);
int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info, u64 bytenr,
u64 offset, int metadata, u64 *refs, u64 *flags,
u64 *owner_root);
int btrfs_pin_extent(struct btrfs_trans_handle *trans, u64 bytenr, u64 num,
int reserved);
int btrfs_pin_extent_for_log_replay(struct btrfs_trans_handle *trans,
const struct extent_buffer *eb);
int btrfs_exclude_logged_extents(struct extent_buffer *eb);
int btrfs_cross_ref_exist(struct btrfs_root *root,
u64 objectid, u64 offset, u64 bytenr, bool strict,
struct btrfs_path *path);
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,
u64 reloc_src_root,
enum btrfs_lock_nesting nest);
int btrfs_free_tree_block(struct btrfs_trans_handle *trans,
u64 root_id,
struct extent_buffer *buf,
u64 parent, int last_ref);
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);
int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
u64 root_objectid, u64 owner, u64 offset,
struct btrfs_key *ins);
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);
int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
struct extent_buffer *buf, int full_backref);
int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
struct extent_buffer *buf, int full_backref);
int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
struct extent_buffer *eb, u64 flags);
int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_ref *ref);
u64 btrfs_get_extent_owner_root(struct btrfs_fs_info *fs_info,
struct extent_buffer *leaf, int slot);
int btrfs_free_reserved_extent(struct btrfs_fs_info *fs_info,
u64 start, u64 len, int delalloc);
int btrfs_pin_reserved_extent(struct btrfs_trans_handle *trans,
const struct extent_buffer *eb);
int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans);
int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans, struct btrfs_ref *generic_ref);
int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref,
int for_reloc);
int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct extent_buffer *node,
struct extent_buffer *parent);
#endif