locks: allow {vfs,posix}_lock_file to return conflicting lock
The nfsv4 protocol's lock operation, in the case of a conflict, returns
information about the conflicting lock.
It's unclear how clients can use this, so for now we're not going so far as to
add a filesystem method that can return a conflicting lock, but we may as well
return something in the local case when it's easy to.
Signed-off-by: Marc Eshel <eshel@almaden.ibm.com>
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index e42c7a0..03b0578 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -2657,6 +2657,7 @@
struct file_lock conflock;
__be32 status = 0;
unsigned int strhashval;
+ unsigned int cmd;
int err;
dprintk("NFSD: nfsd4_lock: start=%Ld length=%Ld\n",
@@ -2739,10 +2740,12 @@
case NFS4_READ_LT:
case NFS4_READW_LT:
file_lock.fl_type = F_RDLCK;
+ cmd = F_SETLK;
break;
case NFS4_WRITE_LT:
case NFS4_WRITEW_LT:
file_lock.fl_type = F_WRLCK;
+ cmd = F_SETLK;
break;
default:
status = nfserr_inval;
@@ -2769,9 +2772,8 @@
/* XXX?: Just to divert the locks_release_private at the start of
* locks_copy_lock: */
- conflock.fl_ops = NULL;
- conflock.fl_lmops = NULL;
- err = posix_lock_file_conf(filp, &file_lock, &conflock);
+ locks_init_lock(&conflock);
+ err = posix_lock_file(filp, &file_lock, &conflock);
switch (-err) {
case 0: /* success! */
update_stateid(&lock_stp->st_stateid);
@@ -2933,7 +2935,7 @@
/*
* Try to unlock the file in the VFS.
*/
- err = posix_lock_file(filp, &file_lock);
+ err = posix_lock_file(filp, &file_lock, NULL);
if (err) {
dprintk("NFSD: nfs4_locku: posix_lock_file failed!\n");
goto out_nfserr;