Commit 1a747ee0 authored by J. Bruce Fields's avatar J. Bruce Fields
Browse files

locks: don't call ->copy_lock methods on return of conflicting locks 



The file_lock structure is used both as a heavy-weight representation of
an active lock, with pointers to reference-counted structures, etc., and
as a simple container for parameters that describe a file lock.

The conflicting lock returned from __posix_lock_file is an example of
the latter; so don't call the filesystem or lock manager callbacks when
copying to it.  This also saves the need for an unnecessary
locks_init_lock in the nfsv4 server.

Thanks to Trond for pointing out the error.

Signed-off-by: default avatarJ. Bruce Fields <bfields@citi.umich.edu>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
parent 17efa372

fs/lockd/svclock.c

+1 −1
Original line number Diff line number Diff line
@@ -632,7 +632,7 @@ nlmsvc_update_deferred_block(struct nlm_block *block, struct file_lock *conf, 
		block->b_flags |= B_TIMED_OUT;

	if (conf) {

		if (block->b_fl)

			locks_copy_lock(block->b_fl, conf);

			__locks_copy_lock(block->b_fl, conf);

	}

}

fs/locks.c

+2 −2
Original line number Diff line number Diff line
@@ -224,7 +224,7 @@ static void locks_copy_private(struct file_lock *new, struct file_lock *fl) 
/*

 * Initialize a new lock from an existing file_lock structure.

 */

static void __locks_copy_lock(struct file_lock *new, const struct file_lock *fl)

void __locks_copy_lock(struct file_lock *new, const struct file_lock *fl)

{

	new->fl_owner = fl->fl_owner;

	new->fl_pid = fl->fl_pid;
@@ -833,7 +833,7 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request, str 
			if (!posix_locks_conflict(request, fl))

				continue;

			if (conflock)

				locks_copy_lock(conflock, fl);

				__locks_copy_lock(conflock, fl);

			error = -EAGAIN;

			if (!(request->fl_flags & FL_SLEEP))

				goto out;

fs/nfsd/nfs4state.c

+0 −3
Original line number Diff line number Diff line
@@ -2712,9 +2712,6 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, 
	* Note: locks.c uses the BKL to protect the inode's lock list.

	*/



	/* XXX?: Just to divert the locks_release_private at the start of

	 * locks_copy_lock: */

	locks_init_lock(&conflock);

	err = vfs_lock_file(filp, cmd, &file_lock, &conflock);

	switch (-err) {

	case 0: /* success! */

include/linux/fs.h

+1 −0
Original line number Diff line number Diff line
@@ -973,6 +973,7 @@ extern int do_sync_mapping_range(struct address_space *mapping, loff_t offset, 
/* fs/locks.c */

extern void locks_init_lock(struct file_lock *);

extern void locks_copy_lock(struct file_lock *, struct file_lock *);

extern void __locks_copy_lock(struct file_lock *, const struct file_lock *);

extern void locks_remove_posix(struct file *, fl_owner_t);

extern void locks_remove_flock(struct file *);

extern void posix_test_lock(struct file *, struct file_lock *);

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