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authorLinus Torvalds <torvalds@g5.osdl.org>2006-07-05 13:05:15 -0700
committerLinus Torvalds <torvalds@g5.osdl.org>2006-07-05 13:05:15 -0700
commita942b57b9577f30da46a9f16ea0ef2c372cb15a4 (patch)
treee62017f1b154dc1ffe0c2a95fc654fb16e98fe5c /fs/locks.c
parent887e5d5fcc96e3a7c91e19d9bb419c10196ffdc1 (diff)
parent72dbac37e3a0acf8e8f07fc65e34e83de83e0b28 (diff)
downloadlwn-a942b57b9577f30da46a9f16ea0ef2c372cb15a4.tar.gz
lwn-a942b57b9577f30da46a9f16ea0ef2c372cb15a4.zip
Merge git://git.linux-nfs.org/pub/linux/nfs-2.6
* git://git.linux-nfs.org/pub/linux/nfs-2.6: NLM,NFSv4: Wait on local locks before we put RPC calls on the wire VFS: Add support for the FL_ACCESS flag to flock_lock_file() NFSv4: Ensure nfs4_lock_expired() caches delegated locks NLM,NFSv4: Don't put UNLOCK requests on the wire unless we hold a lock VFS: Allow caller to determine if BSD or posix locks were actually freed NFS: Optimise away an excessive GETATTR call when a file is symlinked This fixes a panic doing the first READDIR or READDIRPLUS call when: NFS: Fix NFS page_state usage Revert "Merge branch 'odirect'"
Diffstat (limited to 'fs/locks.c')
-rw-r--r--fs/locks.c23
1 files changed, 21 insertions, 2 deletions
diff --git a/fs/locks.c b/fs/locks.c
index 1ad29c9b6252..b0b41a64e10b 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -725,6 +725,10 @@ next_task:
/* Try to create a FLOCK lock on filp. We always insert new FLOCK locks
* at the head of the list, but that's secret knowledge known only to
* flock_lock_file and posix_lock_file.
+ *
+ * Note that if called with an FL_EXISTS argument, the caller may determine
+ * whether or not a lock was successfully freed by testing the return
+ * value for -ENOENT.
*/
static int flock_lock_file(struct file *filp, struct file_lock *request)
{
@@ -735,6 +739,8 @@ static int flock_lock_file(struct file *filp, struct file_lock *request)
int found = 0;
lock_kernel();
+ if (request->fl_flags & FL_ACCESS)
+ goto find_conflict;
for_each_lock(inode, before) {
struct file_lock *fl = *before;
if (IS_POSIX(fl))
@@ -750,8 +756,11 @@ static int flock_lock_file(struct file *filp, struct file_lock *request)
break;
}
- if (request->fl_type == F_UNLCK)
+ if (request->fl_type == F_UNLCK) {
+ if ((request->fl_flags & FL_EXISTS) && !found)
+ error = -ENOENT;
goto out;
+ }
error = -ENOMEM;
new_fl = locks_alloc_lock();
@@ -764,6 +773,7 @@ static int flock_lock_file(struct file *filp, struct file_lock *request)
if (found)
cond_resched();
+find_conflict:
for_each_lock(inode, before) {
struct file_lock *fl = *before;
if (IS_POSIX(fl))
@@ -777,6 +787,8 @@ static int flock_lock_file(struct file *filp, struct file_lock *request)
locks_insert_block(fl, request);
goto out;
}
+ if (request->fl_flags & FL_ACCESS)
+ goto out;
locks_copy_lock(new_fl, request);
locks_insert_lock(&inode->i_flock, new_fl);
new_fl = NULL;
@@ -948,8 +960,11 @@ static int __posix_lock_file_conf(struct inode *inode, struct file_lock *request
error = 0;
if (!added) {
- if (request->fl_type == F_UNLCK)
+ if (request->fl_type == F_UNLCK) {
+ if (request->fl_flags & FL_EXISTS)
+ error = -ENOENT;
goto out;
+ }
if (!new_fl) {
error = -ENOLCK;
@@ -996,6 +1011,10 @@ static int __posix_lock_file_conf(struct inode *inode, struct file_lock *request
* Add a POSIX style lock to a file.
* We merge adjacent & overlapping locks whenever possible.
* POSIX locks are sorted by owner task, then by starting address
+ *
+ * Note that if called with an FL_EXISTS argument, the caller may determine
+ * whether or not a lock was successfully freed by testing the return
+ * value for -ENOENT.
*/
int posix_lock_file(struct file *filp, struct file_lock *fl)
{