ipc: unify the syscalls code

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

diff --git a/ipc/util.c b/ipc/util.c
index 2a205875d277bcce202306124a332cbb1fa07c36..03b88798f71f642e4e1a070137c97f5110d8b4da 100644 (file)
--- a/ipc/util.c
+++ b/ipc/util.c
@@ -197,7 +197,7 @@ void __init ipc_init_proc_interface(const char *path, const char *header,
  *     If key is found ipc contains its ipc structure
  */
  
-struct kern_ipc_perm *ipc_findkey(struct ipc_ids *ids, key_t key)
+static struct kern_ipc_perm *ipc_findkey(struct ipc_ids *ids, key_t key)
 {
        struct kern_ipc_perm *ipc;
        int next_id;
@@ -300,6 +300,105 @@ int ipc_addid(struct ipc_ids* ids, struct kern_ipc_perm* new, int size)
        return id;
 }
 
+/**
+ *     ipcget_new      -       create a new ipc object
+ *     @ns: namespace
+ *     @ids: identifer set
+ *     @ops: the actual creation routine to call
+ *     @params: its parameters
+ *
+ *     This routine is called sys_msgget, sys_semget() and sys_shmget() when
+ *     the key is IPC_PRIVATE
+ */
+int ipcget_new(struct ipc_namespace *ns, struct ipc_ids *ids,
+               struct ipc_ops *ops, struct ipc_params *params)
+{
+       int err;
+
+       err = idr_pre_get(&ids->ipcs_idr, GFP_KERNEL);
+
+       if (!err)
+               return -ENOMEM;
+
+       mutex_lock(&ids->mutex);
+       err = ops->getnew(ns, params);
+       mutex_unlock(&ids->mutex);
+
+       return err;
+}
+
+/**
+ *     ipc_check_perms -       check security and permissions for an IPC
+ *     @ipcp: ipc permission set
+ *     @ids: identifer set
+ *     @ops: the actual security routine to call
+ *     @params: its parameters
+ */
+static int ipc_check_perms(struct kern_ipc_perm *ipcp, struct ipc_ops *ops,
+                       struct ipc_params *params)
+{
+       int err;
+
+       if (ipcperms(ipcp, params->flg))
+               err = -EACCES;
+       else {
+               err = ops->associate(ipcp, params->flg);
+               if (!err)
+                       err = ipcp->id;
+       }
+
+       return err;
+}
+
+/**
+ *     ipcget_public   -       get an ipc object or create a new one
+ *     @ns: namespace
+ *     @ids: identifer set
+ *     @ops: the actual creation routine to call
+ *     @params: its parameters
+ *
+ *     This routine is called sys_msgget, sys_semget() and sys_shmget() when
+ *     the key is not IPC_PRIVATE
+ */
+int ipcget_public(struct ipc_namespace *ns, struct ipc_ids *ids,
+               struct ipc_ops *ops, struct ipc_params *params)
+{
+       struct kern_ipc_perm *ipcp;
+       int flg = params->flg;
+       int err;
+
+       err = idr_pre_get(&ids->ipcs_idr, GFP_KERNEL);
+
+       mutex_lock(&ids->mutex);
+       ipcp = ipc_findkey(ids, params->key);
+       if (ipcp == NULL) {
+               /* key not used */
+               if (!(flg & IPC_CREAT))
+                       err = -ENOENT;
+               else if (!err)
+                       err = -ENOMEM;
+               else
+                       err = ops->getnew(ns, params);
+       } else {
+               /* ipc object has been locked by ipc_findkey() */
+
+               if (flg & IPC_CREAT && flg & IPC_EXCL)
+                       err = -EEXIST;
+               else {
+                       err = 0;
+                       if (ops->more_checks)
+                               err = ops->more_checks(ipcp, params);
+                       if (!err)
+                               err = ipc_check_perms(ipcp, ops, params);
+               }
+               ipc_unlock(ipcp);
+       }
+       mutex_unlock(&ids->mutex);
+
+       return err;
+}
+
+
 /**
  *     ipc_rmid        -       remove an IPC identifier
  *     @ids: identifier set