switch inotify_user to anon_inode

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

switch inotify_user to anon_inode
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Al Viro
1 parent cccc6bba3f
Showing 2 changed files with 6 additions and 54 deletions Side-by-side Diff
fs/notify/inotify/inotify_user.c
include/linux/magic.h
@@ -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 @@
 {
 	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 @@
 	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 @@
  
 	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 @@
 	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 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);
  
@@ -52,7 +52,6 @@
 #define CGROUP_SUPER_MAGIC	0x27e0eb
  
 #define FUTEXFS_SUPER_MAGIC	0xBAD1DEA
-#define INOTIFYFS_SUPER_MAGIC	0x2BAD1DEA
  
 #define STACK_END_MAGIC		0x57AC6E9D
...	...	@@ -29,14 +29,12 @@
29	29	#include <linux/init.h> /* module_init */
30	30	#include <linux/inotify.h>
31	31	#include <linux/kernel.h> /* roundup() */
32		-#include <linux/magic.h> /* superblock magic number */
33		-#include <linux/mount.h> /* mntget */
34	32	#include <linux/namei.h> /* LOOKUP_FOLLOW */
35		-#include <linux/path.h> /* struct path */
36	33	#include <linux/sched.h> /* struct user */
37	34	#include <linux/slab.h> /* struct kmem_cache */
38	35	#include <linux/syscalls.h>
39	36	#include <linux/types.h>
	37	+#include <linux/anon_inodes.h>
40	38	#include <linux/uaccess.h>
41	39	#include <linux/poll.h>
42	40	#include <linux/wait.h>
...	...	@@ -45,8 +43,6 @@
45	43
46	44	#include <asm/ioctls.h>
47	45
48		-static struct vfsmount *inotify_mnt __read_mostly;
49		-
50	46	/* these are configurable via /proc/sys/fs/inotify/ */
51	47	static int inotify_max_user_instances __read_mostly;
52	48	static int inotify_max_queued_events __read_mostly;
...	...	@@ -645,9 +641,7 @@
645	641	{
646	642	struct fsnotify_group *group;
647	643	struct user_struct *user;
648		- struct file *filp;
649		- struct path path;
650		- int fd, ret;
	644	+ int ret;
651	645
652	646	/* Check the IN_* constants for consistency. */
653	647	BUILD_BUG_ON(IN_CLOEXEC != O_CLOEXEC);
...	...	@@ -656,10 +650,6 @@
656	650	if (flags & ~(IN_CLOEXEC \| IN_NONBLOCK))
657	651	return -EINVAL;
658	652
659		- fd = get_unused_fd_flags(flags & O_CLOEXEC);
660		- if (fd < 0)
661		- return fd;
662		-
663	653	user = get_current_user();
664	654	if (unlikely(atomic_read(&user->inotify_devs) >=
665	655	inotify_max_user_instances)) {
666	656
667	657
...	...	@@ -676,27 +666,14 @@
676	666
677	667	atomic_inc(&user->inotify_devs);
678	668
679		- path.mnt = inotify_mnt;
680		- path.dentry = inotify_mnt->mnt_root;
681		- path_get(&path);
682		- filp = alloc_file(&path, FMODE_READ, &inotify_fops);
683		- if (!filp)
684		- goto Enfile;
	669	+ ret = anon_inode_getfd("inotify", &inotify_fops, group,
	670	+ O_RDONLY \| flags);
	671	+ if (ret >= 0)
	672	+ return ret;
685	673
686		- filp->f_flags = O_RDONLY \| (flags & O_NONBLOCK);
687		- filp->private_data = group;
688		-
689		- fd_install(fd, filp);
690		-
691		- return fd;
692		-
693		-Enfile:
694		- ret = -ENFILE;
695		- path_put(&path);
696	674	atomic_dec(&user->inotify_devs);
697	675	out_free_uid:
698	676	free_uid(user);
699		- put_unused_fd(fd);
700	677	return ret;
701	678	}
702	679
...	...	@@ -783,20 +760,6 @@
783	760	return ret;
784	761	}
785	762
786		-static int
787		-inotify_get_sb(struct file_system_type *fs_type, int flags,
788		- const char dev_name, void data, struct vfsmount *mnt)
789		-{
790		- return get_sb_pseudo(fs_type, "inotify", NULL,
791		- INOTIFYFS_SUPER_MAGIC, mnt);
792		-}
793		-
794		-static struct file_system_type inotify_fs_type = {
795		- .name = "inotifyfs",
796		- .get_sb = inotify_get_sb,
797		- .kill_sb = kill_anon_super,
798		-};
799		-
800	763	/*
801	764	* inotify_user_setup - Our initialization function. Note that we cannnot return
802	765	* error because we have compiled-in VFS hooks. So an (unlikely) failure here
...	...	@@ -804,16 +767,6 @@
804	767	*/
805	768	static int __init inotify_user_setup(void)
806	769	{
807		- int ret;
808		-
809		- ret = register_filesystem(&inotify_fs_type);
810		- if (unlikely(ret))
811		- panic("inotify: register_filesystem returned %d!\n", ret);
812		-
813		- inotify_mnt = kern_mount(&inotify_fs_type);
814		- if (IS_ERR(inotify_mnt))
815		- panic("inotify: kern_mount ret %ld!\n", PTR_ERR(inotify_mnt));
816		-
817	770	inotify_inode_mark_cachep = KMEM_CACHE(inotify_inode_mark_entry, SLAB_PANIC);
818	771	event_priv_cachep = KMEM_CACHE(inotify_event_private_data, SLAB_PANIC);
819	772
...	...	@@ -52,7 +52,6 @@
52	52	#define CGROUP_SUPER_MAGIC 0x27e0eb
53	53
54	54	#define FUTEXFS_SUPER_MAGIC 0xBAD1DEA
55		-#define INOTIFYFS_SUPER_MAGIC 0x2BAD1DEA
56	55
57	56	#define STACK_END_MAGIC 0x57AC6E9D
58	57