switch inotify_user to anon_inode

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index a94e8bd..472cdf2 100644 (file)
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -29,14 +29,12 @@
 #include <linux/init.h> /* module_init */
 #include <linux/inotify.h>
 #include <linux/kernel.h> /* roundup() */
-#include <linux/magic.h> /* superblock magic number */
-#include <linux/mount.h> /* mntget */
 #include <linux/namei.h> /* LOOKUP_FOLLOW */
-#include <linux/path.h> /* struct path */
 #include <linux/sched.h> /* struct user */
 #include <linux/slab.h> /* struct kmem_cache */
 #include <linux/syscalls.h>
 #include <linux/types.h>
+#include <linux/anon_inodes.h>
 #include <linux/uaccess.h>
 #include <linux/poll.h>
 #include <linux/wait.h>
@@ -45,8 +43,6 @@
 
 #include <asm/ioctls.h>
 
-static struct vfsmount *inotify_mnt __read_mostly;
-
 /* these are configurable via /proc/sys/fs/inotify/ */
 static int inotify_max_user_instances __read_mostly;
 static int inotify_max_queued_events __read_mostly;
@@ -645,9 +641,7 @@ SYSCALL_DEFINE1(inotify_init1, int, flags)
 {
        struct fsnotify_group *group;
        struct user_struct *user;
-       struct file *filp;
-       struct path path;
-       int fd, ret;
+       int ret;
 
        /* Check the IN_* constants for consistency.  */
        BUILD_BUG_ON(IN_CLOEXEC != O_CLOEXEC);
@@ -656,10 +650,6 @@ SYSCALL_DEFINE1(inotify_init1, int, flags)
        if (flags & ~(IN_CLOEXEC | IN_NONBLOCK))
                return -EINVAL;
 
-       fd = get_unused_fd_flags(flags & O_CLOEXEC);
-       if (fd < 0)
-               return fd;
-
        user = get_current_user();
        if (unlikely(atomic_read(&user->inotify_devs) >=
                        inotify_max_user_instances)) {
@@ -676,27 +666,14 @@ SYSCALL_DEFINE1(inotify_init1, int, flags)
 
        atomic_inc(&user->inotify_devs);
 
-       path.mnt = inotify_mnt;
-       path.dentry = inotify_mnt->mnt_root;
-       path_get(&path);
-       filp = alloc_file(&path, FMODE_READ, &inotify_fops);
-       if (!filp)
-               goto Enfile;
+       ret = anon_inode_getfd("inotify", &inotify_fops, group,
+                                 O_RDONLY | flags);
+       if (ret >= 0)
+               return ret;
 
-       filp->f_flags = O_RDONLY | (flags & O_NONBLOCK);
-       filp->private_data = group;
-
-       fd_install(fd, filp);
-
-       return fd;
-
-Enfile:
-       ret = -ENFILE;
-       path_put(&path);
        atomic_dec(&user->inotify_devs);
 out_free_uid:
        free_uid(user);
-       put_unused_fd(fd);
        return ret;
 }
 
@@ -783,20 +760,6 @@ out:
        return ret;
 }
 
-static int
-inotify_get_sb(struct file_system_type *fs_type, int flags,
-              const char *dev_name, void *data, struct vfsmount *mnt)
-{
-       return get_sb_pseudo(fs_type, "inotify", NULL,
-                       INOTIFYFS_SUPER_MAGIC, mnt);
-}
-
-static struct file_system_type inotify_fs_type = {
-    .name      = "inotifyfs",
-    .get_sb    = inotify_get_sb,
-    .kill_sb   = kill_anon_super,
-};
-
 /*
  * inotify_user_setup - Our initialization function.  Note that we cannnot return
  * error because we have compiled-in VFS hooks.  So an (unlikely) failure here
@@ -804,16 +767,6 @@ static struct file_system_type inotify_fs_type = {
  */
 static int __init inotify_user_setup(void)
 {
-       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_inode_mark_cachep = KMEM_CACHE(inotify_inode_mark_entry, SLAB_PANIC);
        event_priv_cachep = KMEM_CACHE(inotify_event_private_data, SLAB_PANIC);
 

diff --git a/include/linux/magic.h b/include/linux/magic.h
index 76285e0..eb9800f 100644 (file)
--- a/include/linux/magic.h
+++ b/include/linux/magic.h
@@ -52,7 +52,6 @@
 #define CGROUP_SUPER_MAGIC     0x27e0eb
 
 #define FUTEXFS_SUPER_MAGIC    0xBAD1DEA
-#define INOTIFYFS_SUPER_MAGIC  0x2BAD1DEA
 
 #define STACK_END_MAGIC                0x57AC6E9D