ipc: rename ids->rw_mutex
Since in some situations the lock can be shared for readers, we shouldn't
be calling it a mutex, rename it to rwsem.
Signed-off-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/ipc/util.c b/ipc/util.c
index 2c8a93b..9a1d779 100644
--- a/ipc/util.c
+++ b/ipc/util.c
@@ -119,7 +119,7 @@
void ipc_init_ids(struct ipc_ids *ids)
{
- init_rwsem(&ids->rw_mutex);
+ init_rwsem(&ids->rwsem);
ids->in_use = 0;
ids->seq = 0;
@@ -174,7 +174,7 @@
* @ids: Identifier set
* @key: The key to find
*
- * Requires ipc_ids.rw_mutex locked.
+ * Requires ipc_ids.rwsem locked.
* Returns the LOCKED pointer to the ipc structure if found or NULL
* if not.
* If key is found ipc points to the owning ipc structure
@@ -208,7 +208,7 @@
* ipc_get_maxid - get the last assigned id
* @ids: IPC identifier set
*
- * Called with ipc_ids.rw_mutex held.
+ * Called with ipc_ids.rwsem held.
*/
int ipc_get_maxid(struct ipc_ids *ids)
@@ -246,7 +246,7 @@
* is returned. The 'new' entry is returned in a locked state on success.
* On failure the entry is not locked and a negative err-code is returned.
*
- * Called with writer ipc_ids.rw_mutex held.
+ * Called with writer ipc_ids.rwsem held.
*/
int ipc_addid(struct ipc_ids* ids, struct kern_ipc_perm* new, int size)
{
@@ -312,9 +312,9 @@
{
int err;
- down_write(&ids->rw_mutex);
+ down_write(&ids->rwsem);
err = ops->getnew(ns, params);
- up_write(&ids->rw_mutex);
+ up_write(&ids->rwsem);
return err;
}
@@ -331,7 +331,7 @@
*
* On success, the IPC id is returned.
*
- * It is called with ipc_ids.rw_mutex and ipcp->lock held.
+ * It is called with ipc_ids.rwsem and ipcp->lock held.
*/
static int ipc_check_perms(struct ipc_namespace *ns,
struct kern_ipc_perm *ipcp,
@@ -376,7 +376,7 @@
* Take the lock as a writer since we are potentially going to add
* a new entry + read locks are not "upgradable"
*/
- down_write(&ids->rw_mutex);
+ down_write(&ids->rwsem);
ipcp = ipc_findkey(ids, params->key);
if (ipcp == NULL) {
/* key not used */
@@ -402,7 +402,7 @@
}
ipc_unlock(ipcp);
}
- up_write(&ids->rw_mutex);
+ up_write(&ids->rwsem);
return err;
}
@@ -413,7 +413,7 @@
* @ids: IPC identifier set
* @ipcp: ipc perm structure containing the identifier to remove
*
- * ipc_ids.rw_mutex (as a writer) and the spinlock for this ID are held
+ * ipc_ids.rwsem (as a writer) and the spinlock for this ID are held
* before this function is called, and remain locked on the exit.
*/
@@ -621,7 +621,7 @@
}
/**
- * ipc_lock - Lock an ipc structure without rw_mutex held
+ * ipc_lock - Lock an ipc structure without rwsem held
* @ids: IPC identifier set
* @id: ipc id to look for
*
@@ -748,7 +748,7 @@
* - performs some audit and permission check, depending on the given cmd
* - returns a pointer to the ipc object or otherwise, the corresponding error.
*
- * Call holding the both the rw_mutex and the rcu read lock.
+ * Call holding the both the rwsem and the rcu read lock.
*/
struct kern_ipc_perm *ipcctl_pre_down_nolock(struct ipc_namespace *ns,
struct ipc_ids *ids, int id, int cmd,
@@ -868,7 +868,7 @@
* Take the lock - this will be released by the corresponding
* call to stop().
*/
- down_read(&ids->rw_mutex);
+ down_read(&ids->rwsem);
/* pos < 0 is invalid */
if (*pos < 0)
@@ -895,7 +895,7 @@
ids = &iter->ns->ids[iface->ids];
/* Release the lock we took in start() */
- up_read(&ids->rw_mutex);
+ up_read(&ids->rwsem);
}
static int sysvipc_proc_show(struct seq_file *s, void *it)