From: Ken Preslan <kpreslan@redhat.com>
On Mon, Aug 30, 2004 at 07:05:29PM -0400, Trond Myklebust wrote:
> ...
> Firstly, it would be nice to throw out the existing wait loop in
> sys_flock(), and replace it with a call to this new
> flock_lock_file_wait(). I suppose that can be done in a separate cleanup
> patch, though...
> ...
> One solution that I've already suggested to Ken & co is to use a
> separate f_op->flock() call. That would be my preference, since the
> filesystems have to treat flock and posix locks differently anyway.
> ...
Thanks for the suggestions. Below is a patch that implements both of
them.
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/fs/locks.c | 28 ++++++++--------------------
25-akpm/include/linux/fs.h | 1 +
2 files changed, 9 insertions(+), 20 deletions(-)
diff -puN fs/locks.c~allow-cluster-wide-flock-update fs/locks.c
--- 25/fs/locks.c~allow-cluster-wide-flock-update 2004-09-02 21:05:16.450700032 -0700
+++ 25-akpm/fs/locks.c 2004-09-02 21:05:16.457698968 -0700
@@ -1392,24 +1392,12 @@ asmlinkage long sys_flock(unsigned int f
if (error)
goto out_free;
- if (filp->f_op && filp->f_op->lock) {
- error = filp->f_op->lock(filp,
- (can_sleep) ? F_SETLKW : F_SETLK,
- lock);
- goto out_free;
- }
-
- for (;;) {
- error = flock_lock_file(filp, lock);
- if ((error != -EAGAIN) || !can_sleep)
- break;
- error = wait_event_interruptible(lock->fl_wait, !lock->fl_next);
- if (!error)
- continue;
-
- locks_delete_block(lock);
- break;
- }
+ if (filp->f_op && filp->f_op->flock)
+ error = filp->f_op->flock(filp,
+ (can_sleep) ? F_SETLKW : F_SETLK,
+ lock);
+ else
+ error = flock_lock_file_wait(filp, lock);
out_free:
if (list_empty(&lock->fl_link)) {
@@ -1766,10 +1754,10 @@ void locks_remove_flock(struct file *fil
if (!inode->i_flock)
return;
- if (filp->f_op && filp->f_op->lock) {
+ if (filp->f_op && filp->f_op->flock) {
struct file_lock fl = { .fl_flags = FL_FLOCK,
.fl_type = F_UNLCK };
- filp->f_op->lock(filp, F_SETLKW, &fl);
+ filp->f_op->flock(filp, F_SETLKW, &fl);
}
lock_kernel();
diff -puN include/linux/fs.h~allow-cluster-wide-flock-update include/linux/fs.h
--- 25/include/linux/fs.h~allow-cluster-wide-flock-update 2004-09-02 21:05:16.452699728 -0700
+++ 25-akpm/include/linux/fs.h 2004-09-02 21:05:16.459698664 -0700
@@ -983,6 +983,7 @@ struct file_operations {
unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
int (*check_flags)(int);
int (*dir_notify)(struct file *filp, unsigned long arg);
+ int (*flock) (struct file *, int, struct file_lock *);
};
struct inode_operations {
_