kernel/git/stable/linux.git/fs/btrfs/disk-io.h, branch master

btrfs: remove atomic parameter from btrfs_buffer_uptodate()

2026-04-07T16:56:02+00:00

That parameter was introduced by commit b9fab919b748 ("Btrfs: avoid sleeping in verify_parent_transid while atomic"). At that time we needed to lock the extent buffer range inside the io tree to avoid content changes, thus it could sleep. But that behavior is no longer there, as later commit 9e2aff90fc2a ("btrfs: stop using lock_extent in btrfs_buffer_uptodate") dropped the io tree lock. We can remove the @atomic parameter safely now. Reviewed-by: Filipe Manana Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: revalidate cached tree blocks on the uptodate path

2026-04-07T16:56:02+00:00

read_extent_buffer_pages_nowait() returns immediately when an extent buffer is already marked uptodate. On that cache-hit path, the caller supplied btrfs_tree_parent_check is not re-run. This can let read_tree_root_path() accept a cached tree block whose actual header level/owner does not match the expected value derived from the parent. E.g. a corrupted root item that points to a tree block which doesn't even belong to that root, and has mismatching level/owner. But that tree block is already read and cached, later the corrupted tree root got read from disk and hit the cached tree block. Fix this by re-validating cached extent buffers against the supplied btrfs_tree_parent_check on the uptodate path, and make read_tree_root_path() pass its check to btrfs_buffer_uptodate(). This makes cache hits and fresh reads follow the same tree-parent verification rules, and turns the corruption into a read failure instead of constructing an inconsistent root object. Signed-off-by: ZhengYuan Huang Reviewed-by: Qu Wenruo [ Resolve the conflict with extent_buffer_uptodate() helper, handle transid mismatch case ] Signed-off-by: Qu Wenruo Signed-off-by: David Sterba

btrfs: constify arguments of some functions

2026-04-07T16:55:58+00:00

There are several functions that take pointer arguments but don't need to modify the objects they point to, so add the const qualifiers. Reviewed-by: Qu Wenruo Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: remove max_mirrors argument from write_all_supers()

2026-04-07T16:55:54+00:00

There's no need to pass max_mirrors to write_all_supers() since from the given transaction handle we can infer if we are in a transaction commit or fsync context, so we can determine how many mirrors we need to use. So remove the max_mirror argument from write_all_supers() and stop adjusting it in the callees write_dev_supers() and wait_dev_supers(), simplifying them besides the parameter list for write_all_supers(). Reviewed-by: Qu Wenruo Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: pass transaction handle to write_all_supers()

2026-04-07T16:55:54+00:00

We are holding a transaction In every context we call write_all_supers(), so pass the transaction handle instead of fs_info to it. This will allow us to abort the transaction in write_all_supers() instead of calling btrfs_handle_fs_error() in a later patch. Reviewed-by: Qu Wenruo Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: headers cleanup to remove unnecessary local includes

2025-11-24T21:34:52+00:00

[BUG] When I tried to remove btrfs_bio::fs_info and use btrfs_bio::inode to grab the fs_info, the header "btrfs_inode.h" is needed to access the full btrfs_inode structure. Then btrfs will fail to compile. [CAUSE] There is a recursive including chain: "bio.h" -> "btrfs_inode.h" -> "extent_map.h" -> "compression.h" -> "bio.h" That recursive including is causing problems for btrfs. [ENHANCEMENT] To reduce the risk of recursive including: - Remove unnecessary local includes from btrfs headers Either the included header is pulled in by other headers, or is completely unnecessary. - Remove btrfs local includes if the header only requires a pointer In that case let the implementing C file to pull the required header. This is especially important for headers like "btrfs_inode.h" which pulls in a lot of other btrfs headers, thus it's a mine field of recursive including. - Remove unnecessary temporary structure definition Either if we have included the header defining the structure, or completely unused. Now including "btrfs_inode.h" inside "bio.h" is completely fine, although "btrfs_inode.h" still includes "extent_map.h", but that header only includes "fs.h", no more chain back to "bio.h". Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: convert several int parameters to bool

2025-09-22T08:54:32+00:00

We're almost done cleaning misused int/bool parameters. Convert a bunch of them, found by manual grepping. Note that btrfs_sync_fs() needs an int as it's mandated by the struct super_operations prototype. Reviewed-by: Boris Burkov Signed-off-by: David Sterba

btrfs: get rid of btrfs_read_dev_super()

2025-05-15T12:30:50+00:00

The function is introduced by commit a512bbf855ff ("Btrfs: superblock duplication") at the beginning of btrfs. It leaved a comment saying we'd need a special mount option to read all super blocks, but it's never been implemented and there was not need/request for it. The check/rescue tools are able to start from a specific copy and use it as primary eventually. This means btrfs_read_dev_super() is always reading the first super block, making all the code finding the latest super block unnecessary. Just remove that function and replace all call sites with btrfs_read_disk_super(bdev, 0, false). Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: merge btrfs_read_dev_one_super() into btrfs_read_disk_super()

2025-05-15T12:30:50+00:00

We have two functions to read a super block from a block device: - btrfs_read_dev_one_super() Exported from disk-io.c - btrfs_read_disk_super() Local to volumes.c And they have some minor differences: - btrfs_read_dev_one_super() uses @copy_num Meanwhile btrfs_read_disk_super() relies on the physical and expected bytenr passed from the caller. The parameter list of btrfs_read_dev_one_super() is more user friendly. - btrfs_read_disk_super() makes sure the label is NUL terminated We do not need two different functions doing the same job, so merge the behavior into btrfs_read_disk_super() by: - Remove btrfs_read_dev_one_super() - Export btrfs_read_disk_super() The name pairs with btrfs_release_disk_super() perfectly. - Change the parameter list of btrfs_read_disk_super() to mimic btrfs_read_dev_one_super() All existing callers are calculating the physical address and expect bytenr before calling btrfs_read_disk_super() already. Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: change return type of btree_csum_one_bio() to int

2025-05-15T12:30:48+00:00

The type blk_status_t is from block layer and not related to checksums in our context. Use int internally and do the conversions to blk_status_t as needed in btrfs_bio_csum(). Reviewed-by: Qu Wenruo Signed-off-by: David Sterba