[PATCH] inotify: misc. cleanup

Miscellaneous invariant clean up, comment fixes, and so on.  Trivial
stuff.

Signed-off-by: Robert Love <rml@novell.com>
Signed-off-by: John McCutchan <ttb@tentacle.dhs.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

fs/inotify.c

@@ -62,8 +62,8 @@ int inotify_max_queued_events;
  * Lifetimes of the three main data structures--inotify_device, inode, and
  * inotify_watch--are managed by reference count.
  *
- * inotify_device: Lifetime is from open until release.  Additional references
- * can bump the count via get_inotify_dev() and drop the count via
+ * inotify_device: Lifetime is from inotify_init() until release.  Additional
+ * references can bump the count via get_inotify_dev() and drop the count via
  * put_inotify_dev().
  *
  * inotify_watch: Lifetime is from create_watch() to destory_watch().
@@ -75,7 +75,7 @@ int inotify_max_queued_events;
  */
 
 /*
- * struct inotify_device - represents an open instance of an inotify device
+ * struct inotify_device - represents an inotify instance
  *
  * This structure is protected by the semaphore 'sem'.
  */
@@ -371,7 +371,7 @@ static int find_inode(const char __user *dirname, struct nameidata *nd)
 	/* you can only watch an inode if you have read permissions on it */
 	error = permission(nd->dentry->d_inode, MAY_READ, NULL);
 	if (error) 
-		path_release (nd);
+		path_release(nd);
 	return error;
 }
 
@@ -387,7 +387,8 @@ static struct inotify_watch *create_watch(struct inotify_device *dev,
 	struct inotify_watch *watch;
 	int ret;
 
-	if (atomic_read(&dev->user->inotify_watches) >= inotify_max_user_watches)
+	if (atomic_read(&dev->user->inotify_watches) >=
+			inotify_max_user_watches)
 		return ERR_PTR(-ENOSPC);
 
 	watch = kmem_cache_alloc(watch_cachep, GFP_KERNEL);
@@ -783,15 +784,14 @@ static int inotify_release(struct inode *ignored, struct file *file)
 		inotify_dev_event_dequeue(dev);
 	up(&dev->sem);
 
-	/* free this device: the put matching the get in inotify_open() */
+	/* free this device: the put matching the get in inotify_init() */
 	put_inotify_dev(dev);
 
 	return 0;
 }
 
 /*
- * inotify_ignore - handle the INOTIFY_IGNORE ioctl, asking that a given wd be
- * removed from the device.
+ * inotify_ignore - remove a given wd from this inotify instance.
  *
  * Can sleep.
  */
@@ -856,32 +856,24 @@ asmlinkage long sys_inotify_init(void)
 {
 	struct inotify_device *dev;
 	struct user_struct *user;
-	int ret = -ENOTTY;
-	int fd;
-	struct file *filp;
+	struct file *filp;	
+	int fd, ret;
 
 	fd = get_unused_fd();
-	if (fd < 0) {
-		ret = fd;
-		goto out;
-	}
+	if (fd < 0)
+		return fd;
 
 	filp = get_empty_filp();
 	if (!filp) {
 		put_unused_fd(fd);
 		ret = -ENFILE;
 		goto out;
 	}
-	filp->f_op = &inotify_fops;
-	filp->f_vfsmnt = mntget(inotify_mnt);
-	filp->f_dentry = dget(inotify_mnt->mnt_root);
-	filp->f_mapping = filp->f_dentry->d_inode->i_mapping;
-	filp->f_mode = FMODE_READ;
-	filp->f_flags = O_RDONLY;
 
 	user = get_uid(current->user);
 
-	if (unlikely(atomic_read(&user->inotify_devs) >= inotify_max_user_instances)) {
+	if (unlikely(atomic_read(&user->inotify_devs) >=
+			inotify_max_user_instances)) {
 		ret = -EMFILE;
 		goto out_err;
 	}
@@ -892,6 +884,14 @@ asmlinkage long sys_inotify_init(void)
 		goto out_err;
 	}
 
+	filp->f_op = &inotify_fops;
+	filp->f_vfsmnt = mntget(inotify_mnt);
+	filp->f_dentry = dget(inotify_mnt->mnt_root);
+	filp->f_mapping = filp->f_dentry->d_inode->i_mapping;
+	filp->f_mode = FMODE_READ;
+	filp->f_flags = O_RDONLY;
+	filp->private_data = dev;
+
 	idr_init(&dev->idr);
 	INIT_LIST_HEAD(&dev->events);
 	INIT_LIST_HEAD(&dev->watches);
@@ -905,9 +905,8 @@ asmlinkage long sys_inotify_init(void)
 
 	get_inotify_dev(dev);
 	atomic_inc(&user->inotify_devs);
+	fd_install(fd, filp);
 
-	filp->private_data = dev;
-	fd_install (fd, filp);
 	return fd;
 out_err:
 	put_unused_fd (fd);
@@ -917,7 +916,7 @@ asmlinkage long sys_inotify_init(void)
 	return ret;
 }
 
-asmlinkage long sys_inotify_add_watch(int fd, const char *path, u32 mask)
+asmlinkage long sys_inotify_add_watch(int fd, const char __user *path, u32 mask)
 {
 	struct inotify_watch *watch, *old;
 	struct inode *inode;
@@ -930,21 +929,20 @@ asmlinkage long sys_inotify_add_watch(int fd, const char *path, u32 mask)
 	if (!filp)
 		return -EBADF;
 
-	dev = filp->private_data;
-
-	ret = find_inode((const char __user*) path, &nd);
-	if (ret)
+	ret = find_inode(path, &nd);
+	if (unlikely(ret))
 		goto fput_and_out;
 
-	/* Held in place by reference in nd */
+	/* inode held in place by reference to nd; dev by fget on fd */
 	inode = nd.dentry->d_inode;
+	dev = filp->private_data;
 
 	down(&inode->inotify_sem);
 	down(&dev->sem);
 
 	/* don't let user-space set invalid bits: we don't want flags set */
 	mask &= IN_ALL_EVENTS;
-	if (!mask) {
+	if (unlikely(!mask)) {
 		ret = -EINVAL;
 		goto out;
 	}
@@ -1009,11 +1007,11 @@ static struct file_system_type inotify_fs_type = {
 };
 
 /*
- * inotify_init - Our initialization function.  Note that we cannnot return
+ * inotify_setup - Our initialization function.  Note that we cannnot return
  * error because we have compiled-in VFS hooks.  So an (unlikely) failure here
  * must result in panic().
  */
-static int __init inotify_init(void)
+static int __init inotify_setup(void)
 {
 	register_filesystem(&inotify_fs_type);
 	inotify_mnt = kern_mount(&inotify_fs_type);
@@ -1034,4 +1032,4 @@ static int __init inotify_init(void)
 	return 0;
 }
 
-module_init(inotify_init);
+module_init(inotify_setup);