ipc: unify the syscalls code

[linux-2.6-block.git] / ipc / shm.c

diff --git a/ipc/shm.c b/ipc/shm.c
index dcc333239683d7d15ea427a19b236a6fd769d69d..d20cc25c5bdfb0cc7143584150f394f1f4b49901 100644 (file)
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -68,8 +68,7 @@ static struct ipc_ids init_shm_ids;
 #define shm_buildid(ns, id, seq)       \
        ipc_buildid(&shm_ids(ns), id, seq)
 
-static int newseg (struct ipc_namespace *ns, key_t key,
-               int shmflg, size_t size);
+static int newseg(struct ipc_namespace *, struct ipc_params *);
 static void shm_open(struct vm_area_struct *vma);
 static void shm_close(struct vm_area_struct *vma);
 static void shm_destroy (struct ipc_namespace *ns, struct shmid_kernel *shp);
@@ -341,8 +340,11 @@ static struct vm_operations_struct shm_vm_ops = {
 #endif
 };
 
-static int newseg (struct ipc_namespace *ns, key_t key, int shmflg, size_t size)
+static int newseg(struct ipc_namespace *ns, struct ipc_params *params)
 {
+       key_t key = params->key;
+       int shmflg = params->flg;
+       size_t size = params->u.size;
        int error;
        struct shmid_kernel *shp;
        int numpages = (size + PAGE_SIZE -1) >> PAGE_SHIFT;
@@ -423,57 +425,36 @@ no_file:
        return error;
 }
 
+static inline int shm_security(void *shp, int shmflg)
+{
+       return security_shm_associate((struct shmid_kernel *) shp, shmflg);
+}
+
+static inline int shm_more_checks(void *shp, struct ipc_params *params)
+{
+       if (((struct shmid_kernel *)shp)->shm_segsz < params->u.size)
+               return -EINVAL;
+
+       return 0;
+}
+
 asmlinkage long sys_shmget (key_t key, size_t size, int shmflg)
 {
-       struct shmid_kernel *shp;
-       int err;
        struct ipc_namespace *ns;
+       struct ipc_ops shm_ops;
+       struct ipc_params shm_params;
 
        ns = current->nsproxy->ipc_ns;
 
-       err = idr_pre_get(&shm_ids(ns).ipcs_idr, GFP_KERNEL);
+       shm_ops.getnew = newseg;
+       shm_ops.associate = shm_security;
+       shm_ops.more_checks = shm_more_checks;
 
-       if (key == IPC_PRIVATE) {
-               if (!err)
-                       err = -ENOMEM;
-               else {
-                       mutex_lock(&shm_ids(ns).mutex);
-                       err = newseg(ns, key, shmflg, size);
-                       mutex_unlock(&shm_ids(ns).mutex);
-               }
-       } else {
-               mutex_lock(&shm_ids(ns).mutex);
-               shp = (struct shmid_kernel *) ipc_findkey(&shm_ids(ns), key);
-               if (shp == NULL) {
-                       if (!(shmflg & IPC_CREAT))
-                               err = -ENOENT;
-                       else if (!err)
-                               err = -ENOMEM;
-                       else
-                               err = newseg(ns, key, shmflg, size);
-               } else {
-                       /* shp has been locked by ipc_findkey() */
-
-                       if ((shmflg & IPC_CREAT) && (shmflg & IPC_EXCL))
-                               err = -EEXIST;
-                       else {
-                               if (shp->shm_segsz < size)
-                                       err = -EINVAL;
-                               else if (ipcperms(&shp->shm_perm, shmflg))
-                                       err = -EACCES;
-                               else {
-                                       err = security_shm_associate(shp,
-                                                               shmflg);
-                                       if (!err)
-                                               err = shp->shm_perm.id;
-                               }
-                       }
-                       shm_unlock(shp);
-               }
-               mutex_unlock(&shm_ids(ns).mutex);
-       }
+       shm_params.key = key;
+       shm_params.flg = shmflg;
+       shm_params.u.size = size;
 
-       return err;
+       return ipcget(ns, &shm_ids(ns), &shm_ops, &shm_params);
 }
 
 static inline unsigned long copy_shmid_to_user(void __user *buf, struct shmid64_ds *in, int version)