X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=fs%2Finotify.c;h=2fd97ef547ffcac2b35a3bcee5a37667b8e51ef4;hb=8191151d0933d65fb6b659ffbd765479f0f200e1;hp=a87926584cd284c9aa1d94230cc2a659dc2d86db;hpb=b680716ed28baf549f777fb125fc23ba975985c5;p=linux-2.6

diff --git a/fs/inotify.c b/fs/inotify.c
index a87926584c..2fd97ef547 100644
--- a/fs/inotify.c
+++ b/fs/inotify.c
@@ -37,6 +37,7 @@
 #include <asm/ioctls.h>
 
 static atomic_t inotify_cookie;
+static atomic_t inotify_watches;
 
 static kmem_cache_t *watch_cachep;
 static kmem_cache_t *event_cachep;
@@ -90,6 +91,7 @@ struct inotify_device {
 	unsigned int		queue_size;	/* size of the queue (bytes) */
 	unsigned int		event_count;	/* number of pending events */
 	unsigned int		max_events;	/* maximum number of events */
+	u32			last_wd;	/* the last wd allocated */
 };
 
 /*
@@ -352,7 +354,7 @@ static int inotify_dev_get_wd(struct inotify_device *dev,
 	do {
 		if (unlikely(!idr_pre_get(&dev->idr, GFP_KERNEL)))
 			return -ENOSPC;
-		ret = idr_get_new(&dev->idr, watch, &watch->wd);
+		ret = idr_get_new_above(&dev->idr, watch, dev->last_wd+1, &watch->wd);
 	} while (ret == -EAGAIN);
 
 	return ret;
@@ -401,6 +403,7 @@ static struct inotify_watch *create_watch(struct inotify_device *dev,
 		return ERR_PTR(ret);
 	}
 
+	dev->last_wd = watch->wd;
 	watch->mask = mask;
 	atomic_set(&watch->count, 0);
 	INIT_LIST_HEAD(&watch->d_list);
@@ -420,6 +423,7 @@ static struct inotify_watch *create_watch(struct inotify_device *dev,
 	get_inotify_watch(watch);
 
 	atomic_inc(&dev->user->inotify_watches);
+	atomic_inc(&inotify_watches);
 
 	return watch;
 }
@@ -452,6 +456,7 @@ static void remove_watch_no_event(struct inotify_watch *watch,
 	list_del(&watch->d_list);
 
 	atomic_dec(&dev->user->inotify_watches);
+	atomic_dec(&inotify_watches);
 	idr_remove(&dev->idr, watch->wd);
 	put_inotify_watch(watch);
 }
@@ -530,6 +535,9 @@ void inotify_dentry_parent_queue_event(struct dentry *dentry, u32 mask,
 	struct dentry *parent;
 	struct inode *inode;
 
+	if (!atomic_read (&inotify_watches))
+		return;
+
 	spin_lock(&dentry->d_lock);
 	parent = dentry->d_parent;
 	inode = parent->d_inode;
@@ -865,23 +873,21 @@ asmlinkage long sys_inotify_init(void)
 
 	filp = get_empty_filp();
 	if (!filp) {
-		put_unused_fd(fd);
 		ret = -ENFILE;
-		goto out;
+		goto out_put_fd;
 	}
 
 	user = get_uid(current->user);
-
 	if (unlikely(atomic_read(&user->inotify_devs) >=
 			inotify_max_user_instances)) {
 		ret = -EMFILE;
-		goto out_err;
+		goto out_free_uid;
 	}
 
 	dev = kmalloc(sizeof(struct inotify_device), GFP_KERNEL);
 	if (unlikely(!dev)) {
 		ret = -ENOMEM;
-		goto out_err;
+		goto out_free_uid;
 	}
 
 	filp->f_op = &inotify_fops;
@@ -901,6 +907,7 @@ asmlinkage long sys_inotify_init(void)
 	dev->queue_size = 0;
 	dev->max_events = inotify_max_queued_events;
 	dev->user = user;
+	dev->last_wd = 0;
 	atomic_set(&dev->count, 0);
 
 	get_inotify_dev(dev);
@@ -908,11 +915,11 @@ asmlinkage long sys_inotify_init(void)
 	fd_install(fd, filp);
 
 	return fd;
-out_err:
-	put_unused_fd (fd);
-	put_filp (filp);
+out_free_uid:
 	free_uid(user);
-out:
+	put_filp(filp);
+out_put_fd:
+	put_unused_fd(fd);
 	return ret;
 }
 
@@ -923,12 +930,18 @@ asmlinkage long sys_inotify_add_watch(int fd, const char __user *path, u32 mask)
 	struct inotify_device *dev;
 	struct nameidata nd;
 	struct file *filp;
-	int ret;
+	int ret, fput_needed;
 
-	filp = fget(fd);
-	if (!filp)
+	filp = fget_light(fd, &fput_needed);
+	if (unlikely(!filp))
 		return -EBADF;
 
+	/* verify that this is indeed an inotify instance */
+	if (unlikely(filp->f_op != &inotify_fops)) {
+		ret = -EINVAL;
+		goto fput_and_out;
+	}
+
 	ret = find_inode(path, &nd);
 	if (unlikely(ret))
 		goto fput_and_out;
@@ -969,11 +982,11 @@ 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:
-	path_release (&nd);
 	up(&dev->sem);
 	up(&inode->inotify_sem);
+	path_release(&nd);
 fput_and_out:
-	fput(filp);
+	fput_light(filp, fput_needed);
 	return ret;
 }
 
@@ -981,15 +994,23 @@ asmlinkage long sys_inotify_rm_watch(int fd, u32 wd)
 {
 	struct file *filp;
 	struct inotify_device *dev;
-	int ret;
+	int ret, fput_needed;
 
-	filp = fget(fd);
-	if (!filp)
+	filp = fget_light(fd, &fput_needed);
+	if (unlikely(!filp))
 		return -EBADF;
+
+	/* verify that this is indeed an inotify instance */
+	if (unlikely(filp->f_op != &inotify_fops)) {
+		ret = -EINVAL;
+		goto out;
+	}
+
 	dev = filp->private_data;
 	ret = inotify_ignore(dev, wd);
-	fput(filp);
 
+out:
+	fput_light(filp, fput_needed);
 	return ret;
 }
 
@@ -1013,14 +1034,22 @@ static struct file_system_type inotify_fs_type = {
  */
 static int __init inotify_setup(void)
 {
-	register_filesystem(&inotify_fs_type);
+	int ret;
+
+	ret = register_filesystem(&inotify_fs_type);
+	if (unlikely(ret))
+		panic("inotify: register_filesystem returned %d!\n", ret);
+
 	inotify_mnt = kern_mount(&inotify_fs_type);
+	if (IS_ERR(inotify_mnt))
+		panic("inotify: kern_mount ret %ld!\n", PTR_ERR(inotify_mnt));
 
-	inotify_max_queued_events = 8192;
-	inotify_max_user_instances = 8;
+	inotify_max_queued_events = 16384;
+	inotify_max_user_instances = 128;
 	inotify_max_user_watches = 8192;
 
 	atomic_set(&inotify_cookie, 0);
+	atomic_set(&inotify_watches, 0);
 
 	watch_cachep = kmem_cache_create("inotify_watch_cache",
 					 sizeof(struct inotify_watch),