diff options
| author | Amir Goldstein <amir73il@gmail.com> | 2023-11-22 14:27:14 +0200 |
|---|---|---|
| committer | Christian Brauner <brauner@kernel.org> | 2023-11-24 10:39:19 +0100 |
| commit | 3d5cd4911e04683df8f4439fddd788e00a2510a8 (patch) | |
| tree | 3b5cd5db52f10ff455df222befb343a0c7821095 | |
| parent | 8802e580ee643e3f63c6b39ff64e7c7baa4a55ba (diff) | |
fs: create file_write_started() helper
Convenience wrapper for sb_write_started(file_inode(inode)->i_sb)), which
has a single occurrence in the code right now.
Document the false negatives of those helpers, which makes them unusable
to assert that sb_start_write() is not held.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Link: https://lore.kernel.org/r/20231122122715.2561213-16-amir73il@gmail.com
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
| -rw-r--r-- | fs/read_write.c | 2 | ||||
| -rw-r--r-- | include/linux/fs.h | 21 |
2 files changed, 22 insertions, 1 deletions
diff --git a/fs/read_write.c b/fs/read_write.c index 92c68ab4f221..f791555fa246 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -1423,7 +1423,7 @@ ssize_t generic_copy_file_range(struct file *file_in, loff_t pos_in, struct file *file_out, loff_t pos_out, size_t len, unsigned int flags) { - lockdep_assert(sb_write_started(file_inode(file_out)->i_sb)); + lockdep_assert(file_write_started(file_out)); return do_splice_direct(file_in, &pos_in, file_out, &pos_out, len > MAX_RW_COUNT ? MAX_RW_COUNT : len, 0); diff --git a/include/linux/fs.h b/include/linux/fs.h index ac8b5a9b467b..75a10b632edd 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1659,12 +1659,33 @@ static inline int __sb_write_started(const struct super_block *sb, int level) return lockdep_is_held_type(sb->s_writers.rw_sem + level - 1, 1); } +/** + * sb_write_started - check if SB_FREEZE_WRITE is held + * @sb: the super we write to + * + * May be false positive with !CONFIG_LOCKDEP/LOCK_STATE_UNKNOWN. + */ static inline bool sb_write_started(const struct super_block *sb) { return __sb_write_started(sb, SB_FREEZE_WRITE); } /** + * file_write_started - check if SB_FREEZE_WRITE is held + * @file: the file we write to + * + * May be false positive with !CONFIG_LOCKDEP/LOCK_STATE_UNKNOWN. + * May be false positive with !S_ISREG, because file_start_write() has + * no effect on !S_ISREG. + */ +static inline bool file_write_started(const struct file *file) +{ + if (!S_ISREG(file_inode(file)->i_mode)) + return true; + return sb_write_started(file_inode(file)->i_sb); +} + +/** * sb_end_write - drop write access to a superblock * @sb: the super we wrote to * |