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: J. Bruce Fields <bfields@citi.umich.edu>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
This commit is contained in:
J. Bruce Fields 2008-04-24 10:08:22 -04:00
parent 17efa372cf
commit 1a747ee0cc
4 changed files with 4 additions and 6 deletions

View file

@ -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);
}
}

View file

@ -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;

View file

@ -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! */

View file

@ -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 *);