ipc: use kmalloc for msg_queue and shmid_kernel

msg_queue and shmid_kernel are quite small objects, no need to use
kvmalloc for them.  mhocko@: "Both of them are 256B on most 64b systems."

Previously these objects was allocated via ipc_alloc/ipc_rcu_alloc(),
common function for several ipc objects.  It had kvmalloc call inside().
Later, this function went away and was finally replaced by direct kvmalloc
call, and now we can use more suitable kmalloc/kfree for them.

Link: https://lkml.kernel.org/r/0d0b6c9b-8af3-29d8-34e2-a565c53780f3@virtuozzo.comReported-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Roman Gushchin <guro@fb.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
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/msg.c

@@ -130,7 +130,7 @@ static void msg_rcu_free(struct rcu_head *head)
 	struct msg_queue *msq = container_of(p, struct msg_queue, q_perm);
 
 	security_msg_queue_free(&msq->q_perm);
-	kvfree(msq);
+	kfree(msq);
 }
 
 /**
@@ -147,7 +147,7 @@ static int newque(struct ipc_namespace *ns, struct ipc_params *params)
 	key_t key = params->key;
 	int msgflg = params->flg;
 
-	msq = kvmalloc(sizeof(*msq), GFP_KERNEL);
+	msq = kmalloc(sizeof(*msq), GFP_KERNEL);
 	if (unlikely(!msq))
 		return -ENOMEM;
 
@@ -157,7 +157,7 @@ static int newque(struct ipc_namespace *ns, struct ipc_params *params)
 	msq->q_perm.security = NULL;
 	retval = security_msg_queue_alloc(&msq->q_perm);
 	if (retval) {
-		kvfree(msq);
+		kfree(msq);
 		return retval;
 	}
 

ipc/shm.c

@@ -222,7 +222,7 @@ static void shm_rcu_free(struct rcu_head *head)
 	struct shmid_kernel *shp = container_of(ptr, struct shmid_kernel,
 							shm_perm);
 	security_shm_free(&shp->shm_perm);
-	kvfree(shp);
+	kfree(shp);
 }
 
 static inline void shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *s)
@@ -619,7 +619,7 @@ static int newseg(struct ipc_namespace *ns, struct ipc_params *params)
 			ns->shm_tot + numpages > ns->shm_ctlall)
 		return -ENOSPC;
 
-	shp = kvmalloc(sizeof(*shp), GFP_KERNEL);
+	shp = kmalloc(sizeof(*shp), GFP_KERNEL);
 	if (unlikely(!shp))
 		return -ENOMEM;
 
@@ -630,7 +630,7 @@ static int newseg(struct ipc_namespace *ns, struct ipc_params *params)
 	shp->shm_perm.security = NULL;
 	error = security_shm_alloc(&shp->shm_perm);
 	if (error) {
-		kvfree(shp);
+		kfree(shp);
 		return error;
 	}