[PATCH] sem2mutex: inotify

Semaphore to mutex conversion.

The conversion was generated via scripts, and the result was validated
automatically via a script as well.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: John McCutchan <ttb@tentacle.dhs.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Acked-by: Robert Love <rml@novell.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

fs/inode.c

@@ -206,7 +206,7 @@ void inode_init_once(struct inode *inode)
 	i_size_ordered_init(inode);
 #ifdef CONFIG_INOTIFY
 	INIT_LIST_HEAD(&inode->inotify_watches);
-	sema_init(&inode->inotify_sem, 1);
+	mutex_init(&inode->inotify_mutex);
 #endif
 }
 

fs/inotify.c

@@ -56,8 +56,8 @@ int inotify_max_queued_events;
  * dentry->d_lock (used to keep d_move() away from dentry->d_parent)
  * iprune_sem (synchronize shrink_icache_memory())
  * 	inode_lock (protects the super_block->s_inodes list)
- * 	inode->inotify_sem (protects inode->inotify_watches and watches->i_list)
+ * 	inode->inotify_mutex (protects inode->inotify_watches and watches->i_list)
- * 		inotify_dev->sem (protects inotify_device and watches->d_list)
+ * 		inotify_dev->mutex (protects inotify_device and watches->d_list)
  */
 
 /*
@@ -79,12 +79,12 @@ int inotify_max_queued_events;
 /*
  * struct inotify_device - represents an inotify instance
  *
- * This structure is protected by the semaphore 'sem'.
+ * This structure is protected by the mutex 'mutex'.
  */
 struct inotify_device {
 	wait_queue_head_t 	wq;		/* wait queue for i/o */
 	struct idr		idr;		/* idr mapping wd -> watch */
-	struct semaphore	sem;		/* protects this bad boy */
+	struct mutex		mutex;		/* protects this bad boy */
 	struct list_head 	events;		/* list of queued events */
 	struct list_head	watches;	/* list of watches */
 	atomic_t		count;		/* reference count */
@@ -101,7 +101,7 @@ struct inotify_device {
  * device.  In read(), this list is walked and all events that can fit in the
  * buffer are returned.
  *
- * Protected by dev->sem of the device in which we are queued.
+ * Protected by dev->mutex of the device in which we are queued.
  */
 struct inotify_kernel_event {
 	struct inotify_event	event;	/* the user-space event */
@@ -112,8 +112,8 @@ struct inotify_kernel_event {
 /*
  * struct inotify_watch - represents a watch request on a specific inode
  *
- * d_list is protected by dev->sem of the associated watch->dev.
+ * d_list is protected by dev->mutex of the associated watch->dev.
- * i_list and mask are protected by inode->inotify_sem of the associated inode.
+ * i_list and mask are protected by inode->inotify_mutex of the associated inode.
  * dev, inode, and wd are never written to once the watch is created.
  */
 struct inotify_watch {
@@ -261,7 +261,7 @@ static struct inotify_kernel_event * kernel_event(s32 wd, u32 mask, u32 cookie,
 /*
  * inotify_dev_get_event - return the next event in the given dev's queue
  *
- * Caller must hold dev->sem.
+ * Caller must hold dev->mutex.
  */
 static inline struct inotify_kernel_event *
 inotify_dev_get_event(struct inotify_device *dev)
@@ -272,7 +272,7 @@ inotify_dev_get_event(struct inotify_device *dev)
 /*
  * inotify_dev_queue_event - add a new event to the given device
  *
- * Caller must hold dev->sem.  Can sleep (calls kernel_event()).
+ * Caller must hold dev->mutex.  Can sleep (calls kernel_event()).
  */
 static void inotify_dev_queue_event(struct inotify_device *dev,
 				    struct inotify_watch *watch, u32 mask,
@@ -315,7 +315,7 @@ static void inotify_dev_queue_event(struct inotify_device *dev,
 /*
  * remove_kevent - cleans up and ultimately frees the given kevent
  *
- * Caller must hold dev->sem.
+ * Caller must hold dev->mutex.
  */
 static void remove_kevent(struct inotify_device *dev,
 			  struct inotify_kernel_event *kevent)
@@ -332,7 +332,7 @@ static void remove_kevent(struct inotify_device *dev,
 /*
  * inotify_dev_event_dequeue - destroy an event on the given device
  *
- * Caller must hold dev->sem.
+ * Caller must hold dev->mutex.
  */
 static void inotify_dev_event_dequeue(struct inotify_device *dev)
 {
@@ -346,7 +346,7 @@ static void inotify_dev_event_dequeue(struct inotify_device *dev)
 /*
  * inotify_dev_get_wd - returns the next WD for use by the given dev
  *
- * Callers must hold dev->sem.  This function can sleep.
+ * Callers must hold dev->mutex.  This function can sleep.
  */
 static int inotify_dev_get_wd(struct inotify_device *dev,
 			      struct inotify_watch *watch)
@@ -383,7 +383,7 @@ static int find_inode(const char __user *dirname, struct nameidata *nd,
 /*
  * create_watch - creates a watch on the given device.
  *
- * Callers must hold dev->sem.  Calls inotify_dev_get_wd() so may sleep.
+ * Callers must hold dev->mutex.  Calls inotify_dev_get_wd() so may sleep.
  * Both 'dev' and 'inode' (by way of nameidata) need to be pinned.
  */
 static struct inotify_watch *create_watch(struct inotify_device *dev,
@@ -434,7 +434,7 @@ static struct inotify_watch *create_watch(struct inotify_device *dev,
 /*
  * inotify_find_dev - find the watch associated with the given inode and dev
  *
- * Callers must hold inode->inotify_sem.
+ * Callers must hold inode->inotify_mutex.
  */
 static struct inotify_watch *inode_find_dev(struct inode *inode,
 					    struct inotify_device *dev)
@@ -469,7 +469,7 @@ static void remove_watch_no_event(struct inotify_watch *watch,
  * the IN_IGNORED event to the given device signifying that the inode is no
  * longer watched.
  *
- * Callers must hold both inode->inotify_sem and dev->sem.  We drop a
+ * Callers must hold both inode->inotify_mutex and dev->mutex.  We drop a
  * reference to the inode before returning.
  *
  * The inode is not iput() so as to remain atomic.  If the inode needs to be
@@ -507,21 +507,21 @@ void inotify_inode_queue_event(struct inode *inode, u32 mask, u32 cookie,
 	if (!inotify_inode_watched(inode))
 		return;
 
-	down(&inode->inotify_sem);
+	mutex_lock(&inode->inotify_mutex);
 	list_for_each_entry_safe(watch, next, &inode->inotify_watches, i_list) {
 		u32 watch_mask = watch->mask;
 		if (watch_mask & mask) {
 			struct inotify_device *dev = watch->dev;
 			get_inotify_watch(watch);
-			down(&dev->sem);
+			mutex_lock(&dev->mutex);
 			inotify_dev_queue_event(dev, watch, mask, cookie, name);
 			if (watch_mask & IN_ONESHOT)
 				remove_watch_no_event(watch, dev);
-			up(&dev->sem);
+			mutex_unlock(&dev->mutex);
 			put_inotify_watch(watch);
 		}
 	}
-	up(&inode->inotify_sem);
+	mutex_unlock(&inode->inotify_mutex);
 }
 EXPORT_SYMBOL_GPL(inotify_inode_queue_event);
 
@@ -626,16 +626,16 @@ void inotify_unmount_inodes(struct list_head *list)
 			iput(need_iput_tmp);
 
 		/* for each watch, send IN_UNMOUNT and then remove it */
-		down(&inode->inotify_sem);
+		mutex_lock(&inode->inotify_mutex);
 		watches = &inode->inotify_watches;
 		list_for_each_entry_safe(watch, next_w, watches, i_list) {
 			struct inotify_device *dev = watch->dev;
-			down(&dev->sem);
+			mutex_lock(&dev->mutex);
 			inotify_dev_queue_event(dev, watch, IN_UNMOUNT,0,NULL);
 			remove_watch(watch, dev);
-			up(&dev->sem);
+			mutex_unlock(&dev->mutex);
 		}
-		up(&inode->inotify_sem);
+		mutex_unlock(&inode->inotify_mutex);
 		iput(inode);		
 
 		spin_lock(&inode_lock);
@@ -651,14 +651,14 @@ void inotify_inode_is_dead(struct inode *inode)
 {
 	struct inotify_watch *watch, *next;
 
-	down(&inode->inotify_sem);
+	mutex_lock(&inode->inotify_mutex);
 	list_for_each_entry_safe(watch, next, &inode->inotify_watches, i_list) {
 		struct inotify_device *dev = watch->dev;
-		down(&dev->sem);
+		mutex_lock(&dev->mutex);
 		remove_watch(watch, dev);
-		up(&dev->sem);
+		mutex_unlock(&dev->mutex);
 	}
-	up(&inode->inotify_sem);
+	mutex_unlock(&inode->inotify_mutex);
 }
 EXPORT_SYMBOL_GPL(inotify_inode_is_dead);
 
@@ -670,10 +670,10 @@ static unsigned int inotify_poll(struct file *file, poll_table *wait)
 	int ret = 0;
 
 	poll_wait(file, &dev->wq, wait);
-	down(&dev->sem);
+	mutex_lock(&dev->mutex);
 	if (!list_empty(&dev->events))
 		ret = POLLIN | POLLRDNORM;
-	up(&dev->sem);
+	mutex_unlock(&dev->mutex);
 
 	return ret;
 }
@@ -695,9 +695,9 @@ static ssize_t inotify_read(struct file *file, char __user *buf,
 
 		prepare_to_wait(&dev->wq, &wait, TASK_INTERRUPTIBLE);
 
-		down(&dev->sem);
+		mutex_lock(&dev->mutex);
 		events = !list_empty(&dev->events);
-		up(&dev->sem);
+		mutex_unlock(&dev->mutex);
 		if (events) {
 			ret = 0;
 			break;
@@ -720,7 +720,7 @@ static ssize_t inotify_read(struct file *file, char __user *buf,
 	if (ret)
 		return ret;
 
-	down(&dev->sem);
+	mutex_lock(&dev->mutex);
 	while (1) {
 		struct inotify_kernel_event *kevent;
 
@@ -750,7 +750,7 @@ static ssize_t inotify_read(struct file *file, char __user *buf,
 
 		remove_kevent(dev, kevent);
 	}
-	up(&dev->sem);
+	mutex_unlock(&dev->mutex);
 
 	return ret;
 }
@@ -763,37 +763,37 @@ static int inotify_release(struct inode *ignored, struct file *file)
 	 * Destroy all of the watches on this device.  Unfortunately, not very
 	 * pretty.  We cannot do a simple iteration over the list, because we
 	 * do not know the inode until we iterate to the watch.  But we need to
-	 * hold inode->inotify_sem before dev->sem.  The following works.
+	 * hold inode->inotify_mutex before dev->mutex.  The following works.
 	 */
 	while (1) {
 		struct inotify_watch *watch;
 		struct list_head *watches;
 		struct inode *inode;
 
-		down(&dev->sem);
+		mutex_lock(&dev->mutex);
 		watches = &dev->watches;
 		if (list_empty(watches)) {
-			up(&dev->sem);
+			mutex_unlock(&dev->mutex);
 			break;
 		}
 		watch = list_entry(watches->next, struct inotify_watch, d_list);
 		get_inotify_watch(watch);
-		up(&dev->sem);
+		mutex_unlock(&dev->mutex);
 
 		inode = watch->inode;
-		down(&inode->inotify_sem);
+		mutex_lock(&inode->inotify_mutex);
-		down(&dev->sem);
+		mutex_lock(&dev->mutex);
 		remove_watch_no_event(watch, dev);
-		up(&dev->sem);
+		mutex_unlock(&dev->mutex);
-		up(&inode->inotify_sem);
+		mutex_unlock(&inode->inotify_mutex);
 		put_inotify_watch(watch);
 	}
 
 	/* destroy all of the events on this device */
-	down(&dev->sem);
+	mutex_lock(&dev->mutex);
 	while (!list_empty(&dev->events))
 		inotify_dev_event_dequeue(dev);
-	up(&dev->sem);
+	mutex_unlock(&dev->mutex);
 
 	/* free this device: the put matching the get in inotify_init() */
 	put_inotify_dev(dev);
@@ -811,26 +811,26 @@ static int inotify_ignore(struct inotify_device *dev, s32 wd)
 	struct inotify_watch *watch;
 	struct inode *inode;
 
-	down(&dev->sem);
+	mutex_lock(&dev->mutex);
 	watch = idr_find(&dev->idr, wd);
 	if (unlikely(!watch)) {
-		up(&dev->sem);
+		mutex_unlock(&dev->mutex);
 		return -EINVAL;
 	}
 	get_inotify_watch(watch);
 	inode = watch->inode;
-	up(&dev->sem);
+	mutex_unlock(&dev->mutex);
 
-	down(&inode->inotify_sem);
+	mutex_lock(&inode->inotify_mutex);
-	down(&dev->sem);
+	mutex_lock(&dev->mutex);
 
 	/* make sure that we did not race */
 	watch = idr_find(&dev->idr, wd);
 	if (likely(watch))
 		remove_watch(watch, dev);
 
-	up(&dev->sem);
+	mutex_unlock(&dev->mutex);
-	up(&inode->inotify_sem);
+	mutex_unlock(&inode->inotify_mutex);
 	put_inotify_watch(watch);
 
 	return 0;
@@ -905,7 +905,7 @@ asmlinkage long sys_inotify_init(void)
 	INIT_LIST_HEAD(&dev->events);
 	INIT_LIST_HEAD(&dev->watches);
 	init_waitqueue_head(&dev->wq);
-	sema_init(&dev->sem, 1);
+	mutex_init(&dev->mutex);
 	dev->event_count = 0;
 	dev->queue_size = 0;
 	dev->max_events = inotify_max_queued_events;
@@ -960,8 +960,8 @@ asmlinkage long sys_inotify_add_watch(int fd, const char __user *path, u32 mask)
 	inode = nd.dentry->d_inode;
 	dev = filp->private_data;
 
-	down(&inode->inotify_sem);
+	mutex_lock(&inode->inotify_mutex);
-	down(&dev->sem);
+	mutex_lock(&dev->mutex);
 
 	if (mask & IN_MASK_ADD)
 		mask_add = 1;
@@ -998,8 +998,8 @@ asmlinkage long sys_inotify_add_watch(int fd, const char __user *path, u32 mask)
 	list_add(&watch->i_list, &inode->inotify_watches);
 	ret = watch->wd;
 out:
-	up(&dev->sem);
+	mutex_unlock(&dev->mutex);
-	up(&inode->inotify_sem);
+	mutex_unlock(&inode->inotify_mutex);
 	path_release(&nd);
 fput_and_out:
 	fput_light(filp, fput_needed);

include/linux/fs.h

@@ -509,7 +509,7 @@ struct inode {
 
 #ifdef CONFIG_INOTIFY
 	struct list_head	inotify_watches; /* watches on this inode */
-	struct semaphore	inotify_sem;	/* protects the watches list */
+	struct mutex		inotify_mutex;	/* protects the watches list */
 #endif
 
 	unsigned long		i_state;