2006-09-02 21:36:52

by Roland Dreier

Subject: [PATCH][CIFS] Convert new lock_sem to a mutex

The recent change to "allow Windows blocking locks to be cancelled via
a CANCEL_LOCK call" introduced a new semaphore in struct cifsFileInfo,
lock_sem. However, semaphores used as mutexes are deprecated these
days, and there's no reason to add a new one to the kernel.
Therefore, convert lock_sem to a struct mutex (and also fix one
indentation glitch on one of the lines changed anyway).

Compile tested only, since I don't use CIFS.

Signed-off-by: Roland Dreier <[email protected]>

---

diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index b24006c..5d7048a 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -306,7 +306,7 @@ struct cifsFileInfo {
/* lock scope id (0 if none) */
struct file * pfile; /* needed for writepage */
struct inode * pInode; /* needed for oplock break */
- struct semaphore lock_sem;
+ struct mutex lock_mutex;
struct list_head llist; /* list of byte range locks we have. */
unsigned closePend:1; /* file is marked to close */
unsigned invalidHandle:1; /* file closed via session abend */
diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c
index 914239d..58042f5 100644
--- a/fs/cifs/dir.c
+++ b/fs/cifs/dir.c
@@ -267,7 +267,7 @@ cifs_create(struct inode *inode, struct
pCifsFile->invalidHandle = FALSE;
pCifsFile->closePend = FALSE;
init_MUTEX(&pCifsFile->fh_sem);
- init_MUTEX(&pCifsFile->lock_sem);
+ mutex_init(&pCifsFile->lock_mutex);
INIT_LIST_HEAD(&pCifsFile->llist);
atomic_set(&pCifsFile->wrtPending,0);

diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index e9c5ba9..e27f077 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -48,7 +48,7 @@ static inline struct cifsFileInfo *cifs_
private_data->netfid = netfid;
private_data->pid = current->tgid;
init_MUTEX(&private_data->fh_sem);
- init_MUTEX(&private_data->lock_sem);
+ mutex_init(&private_data->lock_mutex);
INIT_LIST_HEAD(&private_data->llist);
private_data->pfile = file; /* needed for writepage */
private_data->pInode = inode;
@@ -504,12 +504,12 @@ int cifs_close(struct inode *inode, stru

/* Delete any outstanding lock records.
We'll lose them when the file is closed anyway. */
- down(&pSMBFile->lock_sem);
+ mutex_lock(&pSMBFile->lock_mutex);
list_for_each_entry_safe(li, tmp, &pSMBFile->llist, llist) {
list_del(&li->llist);
kfree(li);
}
- up(&pSMBFile->lock_sem);
+ mutex_unlock(&pSMBFile->lock_mutex);

write_lock(&GlobalSMBSeslock);
list_del(&pSMBFile->flist);
@@ -594,9 +594,9 @@ static int store_file_lock(struct cifsFi
li->offset = offset;
li->length = len;
li->type = lockType;
- down(&fid->lock_sem);
+ mutex_lock(&fid->lock_mutex);
list_add(&li->llist, &fid->llist);
- up(&fid->lock_sem);
+ mutex_unlock(&fid->lock_mutex);
return 0;
}

@@ -752,7 +752,7 @@ int cifs_lock(struct file *file, int cmd
int stored_rc = 0;
struct cifsLockInfo *li, *tmp;

- down(&fid->lock_sem);
+ mutex_lock(&fid->lock_mutex);
list_for_each_entry_safe(li, tmp, &fid->llist, llist) {
if (pfLock->fl_start <= li->offset &&
length >= li->length) {
@@ -766,7 +766,7 @@ int cifs_lock(struct file *file, int cmd
kfree(li);
}
}
- up(&fid->lock_sem);
+ mutex_unlock(&fid->lock_mutex);
}
}


--
VGER BF report: H 2.74101e-05

2007-01-15 16:46:48

by Jan Engelhardt

Subject: Re: [PATCH][CIFS] Convert new lock_sem to a mutex

On Sep 2 2006 14:36, Roland Dreier wrote:

>Date: Sat, 02 Sep 2006 14:36:46 -0700
>From: Roland Dreier <[email protected]>
>To: [email protected]
>Cc: [email protected], [email protected]
>Subject: [PATCH][CIFS] Convert new lock_sem to a mutex

A bit dated, however...

since 2.6.20-rc5 still happens to use lock_sem, I tried
this patch (in 2.6.18). Works fine, nothing seemed to
break.


-`J'
--