update VFS documentation for method changes.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index 96d4293..bbcc156 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -92,8 +92,8 @@
 	void (*destroy_inode)(struct inode *);
 	void (*dirty_inode) (struct inode *);
 	int (*write_inode) (struct inode *, int);
-	void (*drop_inode) (struct inode *);
-	void (*delete_inode) (struct inode *);
+	int (*drop_inode) (struct inode *);
+	void (*evict_inode) (struct inode *);
 	void (*put_super) (struct super_block *);
 	void (*write_super) (struct super_block *);
 	int (*sync_fs)(struct super_block *sb, int wait);
@@ -101,14 +101,13 @@
 	int (*unfreeze_fs) (struct super_block *);
 	int (*statfs) (struct dentry *, struct kstatfs *);
 	int (*remount_fs) (struct super_block *, int *, char *);
-	void (*clear_inode) (struct inode *);
 	void (*umount_begin) (struct super_block *);
 	int (*show_options)(struct seq_file *, struct vfsmount *);
 	ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t);
 	ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
 
 locking rules:
-	All may block.
+	All may block [not true, see below]
 	None have BKL
 			s_umount
 alloc_inode:
@@ -116,22 +115,25 @@
 dirty_inode:				(must not sleep)
 write_inode:
 drop_inode:				!!!inode_lock!!!
-delete_inode:
+evict_inode:
 put_super:		write
 write_super:		read
 sync_fs:		read
 freeze_fs:		read
 unfreeze_fs:		read
-statfs:			no
-remount_fs:		maybe		(see below)
-clear_inode:
+statfs:			maybe(read)	(see below)
+remount_fs:		write
 umount_begin:		no
 show_options:		no		(namespace_sem)
 quota_read:		no		(see below)
 quota_write:		no		(see below)
 
-->remount_fs() will have the s_umount exclusive lock if it's already mounted.
-When called from get_sb_single, it does NOT have the s_umount lock.
+->statfs() has s_umount (shared) when called by ustat(2) (native or
+compat), but that's an accident of bad API; s_umount is used to pin
+the superblock down when we only have dev_t given us by userland to
+identify the superblock.  Everything else (statfs(), fstatfs(), etc.)
+doesn't hold it when calling ->statfs() - superblock is pinned down
+by resolving the pathname passed to syscall.
 ->quota_read() and ->quota_write() functions are both guaranteed to
 be the only ones operating on the quota file by the quota code (via
 dqio_sem) (unless an admin really wants to screw up something and