ipc: rename ids->rw_mutex

Since in some situations the lock can be shared for readers, we shouldn't
be calling it a mutex, rename it to rwsem.

Signed-off-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

6 files changed, 68 insertions, 68 deletions

diff --git a/ipc/msg.c b/ipc/msg.c
index b65fdf1a09dd..8203e71bcfbc 100644
--- a/ipc/msg.c
+++ b/ipc/msg.c
@@ -172,7 +172,7 @@ static inline void msg_rmid(struct ipc_namespace *ns, struct msg_queue *s)
  * @ns: namespace
  * @params: ptr to the structure that contains the key and msgflg
  *
- * Called with msg_ids.rw_mutex held (writer)
+ * Called with msg_ids.rwsem held (writer)
  */
 static int newque(struct ipc_namespace *ns, struct ipc_params *params)
 {
@@ -259,8 +259,8 @@ static void expunge_all(struct msg_queue *msq, int res)
  * removes the message queue from message queue ID IDR, and cleans up all the
  * messages associated with this queue.
  *
- * msg_ids.rw_mutex (writer) and the spinlock for this message queue are held
- * before freeque() is called. msg_ids.rw_mutex remains locked on exit.
+ * msg_ids.rwsem (writer) and the spinlock for this message queue are held
+ * before freeque() is called. msg_ids.rwsem remains locked on exit.
  */
 static void freeque(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
 {
@@ -282,7 +282,7 @@ static void freeque(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
 }
 
 /*
- * Called with msg_ids.rw_mutex and ipcp locked.
+ * Called with msg_ids.rwsem and ipcp locked.
  */
 static inline int msg_security(struct kern_ipc_perm *ipcp, int msgflg)
 {
@@ -386,9 +386,9 @@ copy_msqid_from_user(struct msqid64_ds *out, void __user *buf, int version)
 }
 
 /*
- * This function handles some msgctl commands which require the rw_mutex
+ * This function handles some msgctl commands which require the rwsem
  * to be held in write mode.
- * NOTE: no locks must be held, the rw_mutex is taken inside this function.
+ * NOTE: no locks must be held, the rwsem is taken inside this function.
  */
 static int msgctl_down(struct ipc_namespace *ns, int msqid, int cmd,
                        struct msqid_ds __user *buf, int version)
@@ -403,7 +403,7 @@ static int msgctl_down(struct ipc_namespace *ns, int msqid, int cmd,
                         return -EFAULT;
         }
 
-        down_write(&msg_ids(ns).rw_mutex);
+        down_write(&msg_ids(ns).rwsem);
         rcu_read_lock();
 
         ipcp = ipcctl_pre_down_nolock(ns, &msg_ids(ns), msqid, cmd,
@@ -459,7 +459,7 @@ out_unlock0:
 out_unlock1:
         rcu_read_unlock();
 out_up:
-        up_write(&msg_ids(ns).rw_mutex);
+        up_write(&msg_ids(ns).rwsem);
         return err;
 }
 
@@ -494,7 +494,7 @@ static int msgctl_nolock(struct ipc_namespace *ns, int msqid,
                 msginfo.msgmnb = ns->msg_ctlmnb;
                 msginfo.msgssz = MSGSSZ;
                 msginfo.msgseg = MSGSEG;
-                down_read(&msg_ids(ns).rw_mutex);
+                down_read(&msg_ids(ns).rwsem);
                 if (cmd == MSG_INFO) {
                         msginfo.msgpool = msg_ids(ns).in_use;
                         msginfo.msgmap = atomic_read(&ns->msg_hdrs);
@@ -505,7 +505,7 @@ static int msgctl_nolock(struct ipc_namespace *ns, int msqid,
                         msginfo.msgtql = MSGTQL;
                 }
                 max_id = ipc_get_maxid(&msg_ids(ns));
-                up_read(&msg_ids(ns).rw_mutex);
+                up_read(&msg_ids(ns).rwsem);
                 if (copy_to_user(buf, &msginfo, sizeof(struct msginfo)))
                         return -EFAULT;
                 return (max_id < 0) ? 0 : max_id;
diff --git a/ipc/namespace.c b/ipc/namespace.c
index 4be6581d3b7f..d43d9384bb2d 100644
--- a/ipc/namespace.c
+++ b/ipc/namespace.c
@@ -81,7 +81,7 @@ void free_ipcs(struct ipc_namespace *ns, struct ipc_ids *ids,
         int next_id;
         int total, in_use;
 
-        down_write(&ids->rw_mutex);
+        down_write(&ids->rwsem);
 
         in_use = ids->in_use;
 
@@ -93,7 +93,7 @@ void free_ipcs(struct ipc_namespace *ns, struct ipc_ids *ids,
                 free(ns, perm);
                 total++;
         }
-        up_write(&ids->rw_mutex);
+        up_write(&ids->rwsem);
 }
 
 static void free_ipc_ns(struct ipc_namespace *ns)
diff --git a/ipc/sem.c b/ipc/sem.c
index 41088899783d..69b6a21f3844 100644
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -322,7 +322,7 @@ static inline void sem_unlock(struct sem_array *sma, int locknum)
 }
 
 /*
- * sem_lock_(check_) routines are called in the paths where the rw_mutex
+ * sem_lock_(check_) routines are called in the paths where the rwsem
  * is not held.
  *
  * The caller holds the RCU read lock.
@@ -426,7 +426,7 @@ static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s)
  * @ns: namespace
  * @params: ptr to the structure that contains key, semflg and nsems
  *
- * Called with sem_ids.rw_mutex held (as a writer)
+ * Called with sem_ids.rwsem held (as a writer)
  */
 
 static int newary(struct ipc_namespace *ns, struct ipc_params *params)
@@ -492,7 +492,7 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params)
 
 
 /*
- * Called with sem_ids.rw_mutex and ipcp locked.
+ * Called with sem_ids.rwsem and ipcp locked.
  */
 static inline int sem_security(struct kern_ipc_perm *ipcp, int semflg)
 {
@@ -503,7 +503,7 @@ static inline int sem_security(struct kern_ipc_perm *ipcp, int semflg)
 }
 
 /*
- * Called with sem_ids.rw_mutex and ipcp locked.
+ * Called with sem_ids.rwsem and ipcp locked.
  */
 static inline int sem_more_checks(struct kern_ipc_perm *ipcp,
                                 struct ipc_params *params)
@@ -994,8 +994,8 @@ static int count_semzcnt (struct sem_array * sma, ushort semnum)
         return semzcnt;
 }
 
-/* Free a semaphore set. freeary() is called with sem_ids.rw_mutex locked
- * as a writer and the spinlock for this semaphore set hold. sem_ids.rw_mutex
+/* Free a semaphore set. freeary() is called with sem_ids.rwsem locked
+ * as a writer and the spinlock for this semaphore set hold. sem_ids.rwsem
  * remains locked on exit.
  */
 static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
@@ -1116,7 +1116,7 @@ static int semctl_nolock(struct ipc_namespace *ns, int semid,
                 seminfo.semmnu = SEMMNU;
                 seminfo.semmap = SEMMAP;
                 seminfo.semume = SEMUME;
-                down_read(&sem_ids(ns).rw_mutex);
+                down_read(&sem_ids(ns).rwsem);
                 if (cmd == SEM_INFO) {
                         seminfo.semusz = sem_ids(ns).in_use;
                         seminfo.semaem = ns->used_sems;
@@ -1125,7 +1125,7 @@ static int semctl_nolock(struct ipc_namespace *ns, int semid,
                         seminfo.semaem = SEMAEM;
                 }
                 max_id = ipc_get_maxid(&sem_ids(ns));
-                up_read(&sem_ids(ns).rw_mutex);
+                up_read(&sem_ids(ns).rwsem);
                 if (copy_to_user(p, &seminfo, sizeof(struct seminfo))) 
                         return -EFAULT;
                 return (max_id < 0) ? 0: max_id;
@@ -1431,9 +1431,9 @@ copy_semid_from_user(struct semid64_ds *out, void __user *buf, int version)
 }
 
 /*
- * This function handles some semctl commands which require the rw_mutex
+ * This function handles some semctl commands which require the rwsem
  * to be held in write mode.
- * NOTE: no locks must be held, the rw_mutex is taken inside this function.
+ * NOTE: no locks must be held, the rwsem is taken inside this function.
  */
 static int semctl_down(struct ipc_namespace *ns, int semid,
                        int cmd, int version, void __user *p)
@@ -1448,7 +1448,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid,
                         return -EFAULT;
         }
 
-        down_write(&sem_ids(ns).rw_mutex);
+        down_write(&sem_ids(ns).rwsem);
         rcu_read_lock();
 
         ipcp = ipcctl_pre_down_nolock(ns, &sem_ids(ns), semid, cmd,
@@ -1487,7 +1487,7 @@ out_unlock0:
 out_unlock1:
         rcu_read_unlock();
 out_up:
-        up_write(&sem_ids(ns).rw_mutex);
+        up_write(&sem_ids(ns).rwsem);
         return err;
 }
 
diff --git a/ipc/shm.c b/ipc/shm.c
index 28d19f4ece4b..cb2cedaa8808 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -83,8 +83,8 @@ void shm_init_ns(struct ipc_namespace *ns)
 }
 
 /*
- * Called with shm_ids.rw_mutex (writer) and the shp structure locked.
- * Only shm_ids.rw_mutex remains locked on exit.
+ * Called with shm_ids.rwsem (writer) and the shp structure locked.
+ * Only shm_ids.rwsem remains locked on exit.
  */
 static void do_shm_rmid(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
 {
@@ -148,7 +148,7 @@ static inline struct shmid_kernel *shm_obtain_object_check(struct ipc_namespace
 }
 
 /*
- * shm_lock_(check_) routines are called in the paths where the rw_mutex
+ * shm_lock_(check_) routines are called in the paths where the rwsem
  * is not necessarily held.
  */
 static inline struct shmid_kernel *shm_lock(struct ipc_namespace *ns, int id)
@@ -205,7 +205,7 @@ static void shm_open(struct vm_area_struct *vma)
  * @ns: namespace
  * @shp: struct to free
  *
- * It has to be called with shp and shm_ids.rw_mutex (writer) locked,
+ * It has to be called with shp and shm_ids.rwsem (writer) locked,
  * but returns with shp unlocked and freed.
  */
 static void shm_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp)
@@ -253,7 +253,7 @@ static void shm_close(struct vm_area_struct *vma)
         struct shmid_kernel *shp;
         struct ipc_namespace *ns = sfd->ns;
 
-        down_write(&shm_ids(ns).rw_mutex);
+        down_write(&shm_ids(ns).rwsem);
         /* remove from the list of attaches of the shm segment */
         shp = shm_lock(ns, sfd->id);
         BUG_ON(IS_ERR(shp));
@@ -264,10 +264,10 @@ static void shm_close(struct vm_area_struct *vma)
                 shm_destroy(ns, shp);
         else
                 shm_unlock(shp);
-        up_write(&shm_ids(ns).rw_mutex);
+        up_write(&shm_ids(ns).rwsem);
 }
 
-/* Called with ns->shm_ids(ns).rw_mutex locked */
+/* Called with ns->shm_ids(ns).rwsem locked */
 static int shm_try_destroy_current(int id, void *p, void *data)
 {
         struct ipc_namespace *ns = data;
@@ -298,7 +298,7 @@ static int shm_try_destroy_current(int id, void *p, void *data)
         return 0;
 }
 
-/* Called with ns->shm_ids(ns).rw_mutex locked */
+/* Called with ns->shm_ids(ns).rwsem locked */
 static int shm_try_destroy_orphaned(int id, void *p, void *data)
 {
         struct ipc_namespace *ns = data;
@@ -309,7 +309,7 @@ static int shm_try_destroy_orphaned(int id, void *p, void *data)
          * We want to destroy segments without users and with already
          * exit'ed originating process.
          *
-         * As shp->* are changed under rw_mutex, it's safe to skip shp locking.
+         * As shp->* are changed under rwsem, it's safe to skip shp locking.
          */
         if (shp->shm_creator != NULL)
                 return 0;
@@ -323,10 +323,10 @@ static int shm_try_destroy_orphaned(int id, void *p, void *data)
 
 void shm_destroy_orphaned(struct ipc_namespace *ns)
 {
-        down_write(&shm_ids(ns).rw_mutex);
+        down_write(&shm_ids(ns).rwsem);
         if (shm_ids(ns).in_use)
                 idr_for_each(&shm_ids(ns).ipcs_idr, &shm_try_destroy_orphaned, ns);
-        up_write(&shm_ids(ns).rw_mutex);
+        up_write(&shm_ids(ns).rwsem);
 }
 
 
@@ -338,10 +338,10 @@ void exit_shm(struct task_struct *task)
                 return;
 
         /* Destroy all already created segments, but not mapped yet */
-        down_write(&shm_ids(ns).rw_mutex);
+        down_write(&shm_ids(ns).rwsem);
         if (shm_ids(ns).in_use)
                 idr_for_each(&shm_ids(ns).ipcs_idr, &shm_try_destroy_current, ns);
-        up_write(&shm_ids(ns).rw_mutex);
+        up_write(&shm_ids(ns).rwsem);
 }
 
 static int shm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
@@ -475,7 +475,7 @@ static const struct vm_operations_struct shm_vm_ops = {
  * @ns: namespace
  * @params: ptr to the structure that contains key, size and shmflg
  *
- * Called with shm_ids.rw_mutex held as a writer.
+ * Called with shm_ids.rwsem held as a writer.
  */
 
 static int newseg(struct ipc_namespace *ns, struct ipc_params *params)
@@ -583,7 +583,7 @@ no_file:
 }
 
 /*
- * Called with shm_ids.rw_mutex and ipcp locked.
+ * Called with shm_ids.rwsem and ipcp locked.
  */
 static inline int shm_security(struct kern_ipc_perm *ipcp, int shmflg)
 {
@@ -594,7 +594,7 @@ static inline int shm_security(struct kern_ipc_perm *ipcp, int shmflg)
 }
 
 /*
- * Called with shm_ids.rw_mutex and ipcp locked.
+ * Called with shm_ids.rwsem and ipcp locked.
  */
 static inline int shm_more_checks(struct kern_ipc_perm *ipcp,
                                 struct ipc_params *params)
@@ -707,7 +707,7 @@ static inline unsigned long copy_shminfo_to_user(void __user *buf, struct shminf
 
 /*
  * Calculate and add used RSS and swap pages of a shm.
- * Called with shm_ids.rw_mutex held as a reader
+ * Called with shm_ids.rwsem held as a reader
  */
 static void shm_add_rss_swap(struct shmid_kernel *shp,
         unsigned long *rss_add, unsigned long *swp_add)
@@ -734,7 +734,7 @@ static void shm_add_rss_swap(struct shmid_kernel *shp,
 }
 
 /*
- * Called with shm_ids.rw_mutex held as a reader
+ * Called with shm_ids.rwsem held as a reader
  */
 static void shm_get_stat(struct ipc_namespace *ns, unsigned long *rss,
                 unsigned long *swp)
@@ -763,9 +763,9 @@ static void shm_get_stat(struct ipc_namespace *ns, unsigned long *rss,
 }
 
 /*
- * This function handles some shmctl commands which require the rw_mutex
+ * This function handles some shmctl commands which require the rwsem
  * to be held in write mode.
- * NOTE: no locks must be held, the rw_mutex is taken inside this function.
+ * NOTE: no locks must be held, the rwsem is taken inside this function.
  */
 static int shmctl_down(struct ipc_namespace *ns, int shmid, int cmd,
                        struct shmid_ds __user *buf, int version)
@@ -780,7 +780,7 @@ static int shmctl_down(struct ipc_namespace *ns, int shmid, int cmd,
                         return -EFAULT;
         }
 
-        down_write(&shm_ids(ns).rw_mutex);
+        down_write(&shm_ids(ns).rwsem);
         rcu_read_lock();
 
         ipcp = ipcctl_pre_down_nolock(ns, &shm_ids(ns), shmid, cmd,
@@ -819,7 +819,7 @@ out_unlock0:
 out_unlock1:
         rcu_read_unlock();
 out_up:
-        up_write(&shm_ids(ns).rw_mutex);
+        up_write(&shm_ids(ns).rwsem);
         return err;
 }
 
@@ -850,9 +850,9 @@ static int shmctl_nolock(struct ipc_namespace *ns, int shmid,
                 if(copy_shminfo_to_user (buf, &shminfo, version))
                         return -EFAULT;
 
-                down_read(&shm_ids(ns).rw_mutex);
+                down_read(&shm_ids(ns).rwsem);
                 err = ipc_get_maxid(&shm_ids(ns));
-                up_read(&shm_ids(ns).rw_mutex);
+                up_read(&shm_ids(ns).rwsem);
 
                 if(err<0)
                         err = 0;
@@ -863,14 +863,14 @@ static int shmctl_nolock(struct ipc_namespace *ns, int shmid,
                 struct shm_info shm_info;
 
                 memset(&shm_info, 0, sizeof(shm_info));
-                down_read(&shm_ids(ns).rw_mutex);
+                down_read(&shm_ids(ns).rwsem);
                 shm_info.used_ids = shm_ids(ns).in_use;
                 shm_get_stat (ns, &shm_info.shm_rss, &shm_info.shm_swp);
                 shm_info.shm_tot = ns->shm_tot;
                 shm_info.swap_attempts = 0;
                 shm_info.swap_successes = 0;
                 err = ipc_get_maxid(&shm_ids(ns));
-                up_read(&shm_ids(ns).rw_mutex);
+                up_read(&shm_ids(ns).rwsem);
                 if (copy_to_user(buf, &shm_info, sizeof(shm_info))) {
                         err = -EFAULT;
                         goto out;
@@ -1169,7 +1169,7 @@ out_fput:
         fput(file);
 
 out_nattch:
-        down_write(&shm_ids(ns).rw_mutex);
+        down_write(&shm_ids(ns).rwsem);
         shp = shm_lock(ns, shmid);
         BUG_ON(IS_ERR(shp));
         shp->shm_nattch--;
@@ -1177,7 +1177,7 @@ out_nattch:
                 shm_destroy(ns, shp);
         else
                 shm_unlock(shp);
-        up_write(&shm_ids(ns).rw_mutex);
+        up_write(&shm_ids(ns).rwsem);
         return err;
 
 out_unlock:
diff --git a/ipc/util.c b/ipc/util.c
index 2c8a93b380ba..9a1d779a20e2 100644
--- a/ipc/util.c
+++ b/ipc/util.c
@@ -119,7 +119,7 @@ __initcall(ipc_init);
  
 void ipc_init_ids(struct ipc_ids *ids)
 {
-        init_rwsem(&ids->rw_mutex);
+        init_rwsem(&ids->rwsem);
 
         ids->in_use = 0;
         ids->seq = 0;
@@ -174,7 +174,7 @@ void __init ipc_init_proc_interface(const char *path, const char *header,
  *      @ids: Identifier set
  *      @key: The key to find
  *      
- *      Requires ipc_ids.rw_mutex locked.
+ *      Requires ipc_ids.rwsem locked.
  *      Returns the LOCKED pointer to the ipc structure if found or NULL
  *      if not.
  *      If key is found ipc points to the owning ipc structure
@@ -208,7 +208,7 @@ static struct kern_ipc_perm *ipc_findkey(struct ipc_ids *ids, key_t key)
  *      ipc_get_maxid   -       get the last assigned id
  *      @ids: IPC identifier set
  *
- *      Called with ipc_ids.rw_mutex held.
+ *      Called with ipc_ids.rwsem held.
  */
 
 int ipc_get_maxid(struct ipc_ids *ids)
@@ -246,7 +246,7 @@ int ipc_get_maxid(struct ipc_ids *ids)
  *      is returned. The 'new' entry is returned in a locked state on success.
  *      On failure the entry is not locked and a negative err-code is returned.
  *
- *      Called with writer ipc_ids.rw_mutex held.
+ *      Called with writer ipc_ids.rwsem held.
  */
 int ipc_addid(struct ipc_ids* ids, struct kern_ipc_perm* new, int size)
 {
@@ -312,9 +312,9 @@ static int ipcget_new(struct ipc_namespace *ns, struct ipc_ids *ids,
 {
         int err;
 
-        down_write(&ids->rw_mutex);
+        down_write(&ids->rwsem);
         err = ops->getnew(ns, params);
-        up_write(&ids->rw_mutex);
+        up_write(&ids->rwsem);
         return err;
 }
 
@@ -331,7 +331,7 @@ static int ipcget_new(struct ipc_namespace *ns, struct ipc_ids *ids,
  *
  *      On success, the IPC id is returned.
  *
- *      It is called with ipc_ids.rw_mutex and ipcp->lock held.
+ *      It is called with ipc_ids.rwsem and ipcp->lock held.
  */
 static int ipc_check_perms(struct ipc_namespace *ns,
                            struct kern_ipc_perm *ipcp,
@@ -376,7 +376,7 @@ static int ipcget_public(struct ipc_namespace *ns, struct ipc_ids *ids,
          * Take the lock as a writer since we are potentially going to add
          * a new entry + read locks are not "upgradable"
          */
-        down_write(&ids->rw_mutex);
+        down_write(&ids->rwsem);
         ipcp = ipc_findkey(ids, params->key);
         if (ipcp == NULL) {
                 /* key not used */
@@ -402,7 +402,7 @@ static int ipcget_public(struct ipc_namespace *ns, struct ipc_ids *ids,
                 }
                 ipc_unlock(ipcp);
         }
-        up_write(&ids->rw_mutex);
+        up_write(&ids->rwsem);
 
         return err;
 }
@@ -413,7 +413,7 @@ static int ipcget_public(struct ipc_namespace *ns, struct ipc_ids *ids,
  *      @ids: IPC identifier set
  *      @ipcp: ipc perm structure containing the identifier to remove
  *
- *      ipc_ids.rw_mutex (as a writer) and the spinlock for this ID are held
+ *      ipc_ids.rwsem (as a writer) and the spinlock for this ID are held
  *      before this function is called, and remain locked on the exit.
  */
  
@@ -621,7 +621,7 @@ struct kern_ipc_perm *ipc_obtain_object(struct ipc_ids *ids, int id)
 }
 
 /**
- * ipc_lock - Lock an ipc structure without rw_mutex held
+ * ipc_lock - Lock an ipc structure without rwsem held
  * @ids: IPC identifier set
  * @id: ipc id to look for
  *
@@ -748,7 +748,7 @@ int ipc_update_perm(struct ipc64_perm *in, struct kern_ipc_perm *out)
  *  - performs some audit and permission check, depending on the given cmd
  *  - returns a pointer to the ipc object or otherwise, the corresponding error.
  *
- * Call holding the both the rw_mutex and the rcu read lock.
+ * Call holding the both the rwsem and the rcu read lock.
  */
 struct kern_ipc_perm *ipcctl_pre_down_nolock(struct ipc_namespace *ns,
                                         struct ipc_ids *ids, int id, int cmd,
@@ -868,7 +868,7 @@ static void *sysvipc_proc_start(struct seq_file *s, loff_t *pos)
          * Take the lock - this will be released by the corresponding
          * call to stop().
          */
-        down_read(&ids->rw_mutex);
+        down_read(&ids->rwsem);
 
         /* pos < 0 is invalid */
         if (*pos < 0)
@@ -895,7 +895,7 @@ static void sysvipc_proc_stop(struct seq_file *s, void *it)
 
         ids = &iter->ns->ids[iface->ids];
         /* Release the lock we took in start() */
-        up_read(&ids->rw_mutex);
+        up_read(&ids->rwsem);
 }
 
 static int sysvipc_proc_show(struct seq_file *s, void *it)
diff --git a/ipc/util.h b/ipc/util.h
index 41a6c4d26399..0a362ffca972 100644
--- a/ipc/util.h
+++ b/ipc/util.h
@@ -94,10 +94,10 @@ void __init ipc_init_proc_interface(const char *path, const char *header,
 #define ipcid_to_idx(id) ((id) % SEQ_MULTIPLIER)
 #define ipcid_to_seqx(id) ((id) / SEQ_MULTIPLIER)
 
-/* must be called with ids->rw_mutex acquired for writing */
+/* must be called with ids->rwsem acquired for writing */
 int ipc_addid(struct ipc_ids *, struct kern_ipc_perm *, int);
 
-/* must be called with ids->rw_mutex acquired for reading */
+/* must be called with ids->rwsem acquired for reading */
 int ipc_get_maxid(struct ipc_ids *);
 
 /* must be called with both locks acquired. */