ipc: drop ipcctl_pre_down

Now that sem, msgque and shm, through *_down(), all use the lockless
variant of ipcctl_pre_down(), go ahead and delete it.

[akpm@linux-foundation.org: fix function name in kerneldoc, cleanups]
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>

ipc/util.c

@@ -733,7 +733,7 @@ int ipc_update_perm(struct ipc64_perm *in, struct kern_ipc_perm *out)
 }
 
 /**
- * ipcctl_pre_down - retrieve an ipc and check permissions for some IPC_XXX cmd
+ * ipcctl_pre_down_nolock - retrieve an ipc and check permissions for some IPC_XXX cmd
  * @ns:  the ipc namespace
  * @ids:  the table of ids where to look for the ipc
  * @id:   the id of the ipc to retrieve
@@ -746,29 +746,13 @@ int ipc_update_perm(struct ipc64_perm *in, struct kern_ipc_perm *out)
  * It must be called without any lock held and
  *  - retrieves the ipc with the given id in the given table.
  *  - performs some audit and permission check, depending on the given cmd
- *  - returns the ipc with the ipc lock held in case of success
- *    or an err-code without any lock held otherwise.
+ *  - returns a pointer to the ipc object or otherwise, the corresponding error.
  *
  * Call holding the both the rw_mutex and the rcu read lock.
  */
-struct kern_ipc_perm *ipcctl_pre_down(struct ipc_namespace *ns,
-				      struct ipc_ids *ids, int id, int cmd,
-				      struct ipc64_perm *perm, int extra_perm)
-{
-	struct kern_ipc_perm *ipcp;
-
-	ipcp = ipcctl_pre_down_nolock(ns, ids, id, cmd, perm, extra_perm);
-	if (IS_ERR(ipcp))
-		goto out;
-
-	spin_lock(&ipcp->lock);
-out:
-	return ipcp;
-}
-
 struct kern_ipc_perm *ipcctl_pre_down_nolock(struct ipc_namespace *ns,
-					     struct ipc_ids *ids, int id, int cmd,
-					     struct ipc64_perm *perm, int extra_perm)
+					struct ipc_ids *ids, int id, int cmd,
+					struct ipc64_perm *perm, int extra_perm)
 {
 	kuid_t euid;
 	int err = -EPERM;

ipc/util.h

@@ -131,9 +131,6 @@ int ipc_update_perm(struct ipc64_perm *in, struct kern_ipc_perm *out);
 struct kern_ipc_perm *ipcctl_pre_down_nolock(struct ipc_namespace *ns,
 					     struct ipc_ids *ids, int id, int cmd,
 					     struct ipc64_perm *perm, int extra_perm);
-struct kern_ipc_perm *ipcctl_pre_down(struct ipc_namespace *ns,
-				      struct ipc_ids *ids, int id, int cmd,
-				      struct ipc64_perm *perm, int extra_perm);
 
 #ifndef CONFIG_ARCH_WANT_IPC_PARSE_VERSION
   /* On IA-64, we always use the "64-bit version" of the IPC structures.  */