| Message ID | 1651526367-1522-5-git-send-email-dai.ngo@oracle.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | NFSD: Initial implementation of NFSv4 Courteous Server | expand |
On Mon, 2022-05-02 at 14:19 -0700, Dai Ngo wrote: > 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> > --- > 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 8c6df10cd9ed..c369841ef7d1 100644 > --- a/fs/locks.c > +++ b/fs/locks.c > @@ -300,6 +300,34 @@ 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 bbde95387a23..b8ed7f974fb4 100644 > --- a/include/linux/fs.h > +++ b/include/linux/fs.h > @@ -1174,6 +1174,8 @@ 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) > @@ -1309,6 +1311,11 @@ 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) Reviewed-by: Jeff Layton <jlayton@kernel.org>
diff --git a/fs/locks.c b/fs/locks.c index 8c6df10cd9ed..c369841ef7d1 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -300,6 +300,34 @@ 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 bbde95387a23..b8ed7f974fb4 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1174,6 +1174,8 @@ 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) @@ -1309,6 +1311,11 @@ 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)