Storing ipcs into IDRs
This patch converts casts of struct kern_ipc_perm to
. struct msg_queue
. struct sem_array
. struct shmid_kernel
into the equivalent container_of() macro. It improves code maintenance
because the code need not change if kern_ipc_perm is no longer at the
beginning of the containing struct.
Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/ipc/shm.c b/ipc/shm.c
index 8241264..e2de16e 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -139,13 +139,17 @@
static inline struct shmid_kernel *shm_lock(struct ipc_namespace *ns, int id)
{
- return (struct shmid_kernel *) ipc_lock(&shm_ids(ns), id);
+ struct kern_ipc_perm *ipcp = ipc_lock(&shm_ids(ns), id);
+
+ return container_of(ipcp, struct shmid_kernel, shm_perm);
}
static inline struct shmid_kernel *shm_lock_check(struct ipc_namespace *ns,
int id)
{
- return (struct shmid_kernel *) ipc_lock_check(&shm_ids(ns), id);
+ struct kern_ipc_perm *ipcp = ipc_lock_check(&shm_ids(ns), id);
+
+ return container_of(ipcp, struct shmid_kernel, shm_perm);
}
static inline void shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *s)
@@ -424,14 +428,21 @@
return error;
}
-static inline int shm_security(void *shp, int shmflg)
+static inline int shm_security(struct kern_ipc_perm *ipcp, int shmflg)
{
- return security_shm_associate((struct shmid_kernel *) shp, shmflg);
+ struct shmid_kernel *shp;
+
+ shp = container_of(ipcp, struct shmid_kernel, shm_perm);
+ return security_shm_associate(shp, shmflg);
}
-static inline int shm_more_checks(void *shp, struct ipc_params *params)
+static inline int shm_more_checks(struct kern_ipc_perm *ipcp,
+ struct ipc_params *params)
{
- if (((struct shmid_kernel *)shp)->shm_segsz < params->u.size)
+ struct shmid_kernel *shp;
+
+ shp = container_of(ipcp, struct shmid_kernel, shm_perm);
+ if (shp->shm_segsz < params->u.size)
return -EINVAL;
return 0;