5.10-stable review patch. If anyone has any objections, please let me know.
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From: Dai Ngo dai.ngo@oracle.com
[ Upstream commit 591502c5cb325b1c6ec59ab161927d606b918aa0 ]
Add helper locks_owner_has_blockers to check if there is any blockers for a given lockowner.
Reviewed-by: J. Bruce Fields bfields@fieldses.org Signed-off-by: Dai Ngo dai.ngo@oracle.com Signed-off-by: Chuck Lever chuck.lever@oracle.com Reviewed-by: Jeff Layton jlayton@kernel.org Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/locks.c | 28 ++++++++++++++++++++++++++++ include/linux/fs.h | 7 +++++++ 2 files changed, 35 insertions(+)
diff --git a/fs/locks.c b/fs/locks.c index 101867933e4d3..118df2812f8aa 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -376,6 +376,34 @@ void locks_release_private(struct file_lock *fl) } EXPORT_SYMBOL_GPL(locks_release_private);
+/** + * locks_owner_has_blockers - Check for blocking lock requests + * @flctx: file lock context + * @owner: lock owner + * + * Return values: + * %true: @owner has at least one blocker + * %false: @owner has no blockers + */ +bool locks_owner_has_blockers(struct file_lock_context *flctx, + fl_owner_t owner) +{ + struct file_lock *fl; + + spin_lock(&flctx->flc_lock); + list_for_each_entry(fl, &flctx->flc_posix, fl_list) { + if (fl->fl_owner != owner) + continue; + if (!list_empty(&fl->fl_blocked_requests)) { + spin_unlock(&flctx->flc_lock); + return true; + } + } + spin_unlock(&flctx->flc_lock); + return false; +} +EXPORT_SYMBOL_GPL(locks_owner_has_blockers); + /* Free a lock which is not in use. */ void locks_free_lock(struct file_lock *fl) { diff --git a/include/linux/fs.h b/include/linux/fs.h index c0459446e1440..17dc1ee8c6cb2 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1163,6 +1163,8 @@ extern void lease_unregister_notifier(struct notifier_block *); struct files_struct; extern void show_fd_locks(struct seq_file *f, struct file *filp, struct files_struct *files); +extern bool locks_owner_has_blockers(struct file_lock_context *flctx, + fl_owner_t owner); #else /* !CONFIG_FILE_LOCKING */ static inline int fcntl_getlk(struct file *file, unsigned int cmd, struct flock __user *user) @@ -1303,6 +1305,11 @@ static inline int lease_modify(struct file_lock *fl, int arg, struct files_struct; static inline void show_fd_locks(struct seq_file *f, struct file *filp, struct files_struct *files) {} +static inline bool locks_owner_has_blockers(struct file_lock_context *flctx, + fl_owner_t owner) +{ + return false; +} #endif /* !CONFIG_FILE_LOCKING */
static inline struct inode *file_inode(const struct file *f)