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-rw-r--r--fs/inotify.c66
1 files changed, 32 insertions, 34 deletions
diff --git a/fs/inotify.c b/fs/inotify.c
index 54757be..a879265 100644
--- a/fs/inotify.c
+++ b/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.
*/
@@ -856,15 +856,12 @@ 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) {
@@ -872,16 +869,11 @@ asmlinkage long sys_inotify_init(void)
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 @@ out:
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);
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