X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=ipc%2Futil.h;h=f37d160c98fe7c5c42b44d9611979a4a79d793fc;hb=7e59128f31e0c57d52e86d57730d4c9281494dda;hp=1546eda7d99e84f3d07ec6f1b481d3fab7fae0a6;hpb=637c36634029e4e7c81112796dafc32d56355b4a;p=linux-2.6-omap-h63xx.git

diff --git a/ipc/util.h b/ipc/util.h
index 1546eda7d99..f37d160c98f 100644
--- a/ipc/util.h
+++ b/ipc/util.h
@@ -10,7 +10,7 @@
 #ifndef _IPC_UTIL_H
 #define _IPC_UTIL_H
 
-#include <linux/idr.h>
+#include <linux/err.h>
 
 #define USHRT_MAX 0xffff
 #define SEQ_MULTIPLIER	(IPCMNI)
@@ -19,22 +19,16 @@ void sem_init (void);
 void msg_init (void);
 void shm_init (void);
 
-int sem_init_ns(struct ipc_namespace *ns);
-int msg_init_ns(struct ipc_namespace *ns);
-int shm_init_ns(struct ipc_namespace *ns);
+struct ipc_namespace;
+
+void sem_init_ns(struct ipc_namespace *ns);
+void msg_init_ns(struct ipc_namespace *ns);
+void shm_init_ns(struct ipc_namespace *ns);
 
 void sem_exit_ns(struct ipc_namespace *ns);
 void msg_exit_ns(struct ipc_namespace *ns);
 void shm_exit_ns(struct ipc_namespace *ns);
 
-struct ipc_ids {
-	int in_use;
-	unsigned short seq;
-	unsigned short seq_max;
-	struct mutex mutex;
-	struct idr ipcs_idr;
-};
-
 /*
  * Structure that holds the parameters needed by the ipc operations
  * (see after)
@@ -53,18 +47,19 @@ struct ipc_params {
  * the calls to sys_msgget(), sys_semget(), sys_shmget()
  *      . routine to call to create a new ipc object. Can be one of newque,
  *        newary, newseg
- *      . routine to call to call to check permissions for a new ipc object.
+ *      . routine to call to check permissions for a new ipc object.
  *        Can be one of security_msg_associate, security_sem_associate,
  *        security_shm_associate
  *      . routine to call for an extra check if needed
  */
 struct ipc_ops {
 	int (*getnew) (struct ipc_namespace *, struct ipc_params *);
-	int (*associate) (void *, int);
-	int (*more_checks) (void *, struct ipc_params *);
+	int (*associate) (struct kern_ipc_perm *, int);
+	int (*more_checks) (struct kern_ipc_perm *, struct ipc_params *);
 };
 
 struct seq_file;
+struct ipc_ids;
 
 void ipc_init_ids(struct ipc_ids *);
 #ifdef CONFIG_PROC_FS
@@ -78,14 +73,19 @@ void __init ipc_init_proc_interface(const char *path, const char *header,
 #define IPC_MSG_IDS	1
 #define IPC_SHM_IDS	2
 
-/* must be called with ids->mutex acquired.*/
+#define ipcid_to_idx(id) ((id) % SEQ_MULTIPLIER)
+
+/* must be called with ids->rw_mutex acquired for writing */
 int ipc_addid(struct ipc_ids *, struct kern_ipc_perm *, int);
+
+/* must be called with ids->rw_mutex acquired for reading */
 int ipc_get_maxid(struct ipc_ids *);
 
 /* must be called with both locks acquired. */
 void ipc_rmid(struct ipc_ids *, struct kern_ipc_perm *);
 
-int ipcperms (struct kern_ipc_perm *ipcp, short flg);
+/* must be called with ipcp locked */
+int ipcperms(struct kern_ipc_perm *ipcp, short flg);
 
 /* for rare, potentially huge allocations.
  * both function can sleep
@@ -103,11 +103,12 @@ void* ipc_rcu_alloc(int size);
 void ipc_rcu_getref(void *ptr);
 void ipc_rcu_putref(void *ptr);
 
-struct kern_ipc_perm* ipc_lock(struct ipc_ids* ids, int id);
-void ipc_lock_by_ptr(struct kern_ipc_perm *ipcp);
-void ipc_unlock(struct kern_ipc_perm* perm);
-int ipc_buildid(struct ipc_ids* ids, int id, int seq);
-int ipc_checkid(struct ipc_ids* ids, struct kern_ipc_perm* ipcp, int uid);
+/*
+ * ipc_lock_down: called with rw_mutex held
+ * ipc_lock: called without that lock held
+ */
+struct kern_ipc_perm *ipc_lock_down(struct ipc_ids *, int);
+struct kern_ipc_perm *ipc_lock(struct ipc_ids *, int);
 
 void kernel_to_ipc64_perm(struct kern_ipc_perm *in, struct ipc64_perm *out);
 void ipc64_perm_to_ipc_perm(struct ipc64_perm *in, struct ipc_perm *out);
@@ -122,18 +123,37 @@ int ipc_parse_version (int *cmd);
 extern void free_msg(struct msg_msg *msg);
 extern struct msg_msg *load_msg(const void __user *src, int len);
 extern int store_msg(void __user *dest, struct msg_msg *msg, int len);
-extern int ipcget_new(struct ipc_namespace *, struct ipc_ids *,
-			struct ipc_ops *, struct ipc_params *);
-extern int ipcget_public(struct ipc_namespace *, struct ipc_ids *,
-			struct ipc_ops *, struct ipc_params *);
 
-static inline int ipcget(struct ipc_namespace *ns, struct ipc_ids *ids,
-			struct ipc_ops *ops, struct ipc_params *params)
+static inline int ipc_buildid(int id, int seq)
 {
-	if (params->key == IPC_PRIVATE)
-		return ipcget_new(ns, ids, ops, params);
-	else
-		return ipcget_public(ns, ids, ops, params);
+	return SEQ_MULTIPLIER * seq + id;
 }
 
+/*
+ * Must be called with ipcp locked
+ */
+static inline int ipc_checkid(struct kern_ipc_perm *ipcp, int uid)
+{
+	if (uid / SEQ_MULTIPLIER != ipcp->seq)
+		return 1;
+	return 0;
+}
+
+static inline void ipc_lock_by_ptr(struct kern_ipc_perm *perm)
+{
+	rcu_read_lock();
+	spin_lock(&perm->lock);
+}
+
+static inline void ipc_unlock(struct kern_ipc_perm *perm)
+{
+	spin_unlock(&perm->lock);
+	rcu_read_unlock();
+}
+
+struct kern_ipc_perm *ipc_lock_check_down(struct ipc_ids *ids, int id);
+struct kern_ipc_perm *ipc_lock_check(struct ipc_ids *ids, int id);
+int ipcget(struct ipc_namespace *ns, struct ipc_ids *ids,
+			struct ipc_ops *ops, struct ipc_params *params);
+
 #endif