[PATCH] update block_device_operations documentation

[PATCH] update block_device_operations documentation

[Christoph Hellwig]

Updated Documentation/filesystems/Locking to match the code.

Signed-off-by: Christoph Hellwig <hch@lst.de>

Index: linux-2.6/Documentation/filesystems/Locking
===================================================================
--- linux-2.6.orig/Documentation/filesystems/Locking	2010-09-20 17:43:52.944444174 +0200
+++ linux-2.6/Documentation/filesystems/Locking	2010-09-22 11:34:48.213032570 +0200
@@ -349,21 +349,36 @@ call this method upon the IO completion.
 
 --------------------------- block_device_operations -----------------------
 prototypes:
-	int (*open) (struct inode *, struct file *);
-	int (*release) (struct inode *, struct file *);
-	int (*ioctl) (struct inode *, struct file *, unsigned, unsigned long);
+	int (*open) (struct block_device *, fmode_t);
+	int (*release) (struct gendisk *, fmode_t);
+	int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
+	int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
+	int (*direct_access) (struct block_device *, sector_t, void **, unsigned long *);
 	int (*media_changed) (struct gendisk *);
+	void (*unlock_native_capacity) (struct gendisk *);
 	int (*revalidate_disk) (struct gendisk *);
+	int (*getgeo)(struct block_device *, struct hd_geometry *);
+	void (*swap_slot_free_notify) (struct block_device *, unsigned long);
 
 locking rules:
-			BKL	bd_sem
-open:			yes	yes
-release:		yes	yes
-ioctl:			yes	no
+			BKL	bd_mutex
+open:			no	yes
+release:		no	yes
+ioctl:			no	no
+compat_ioctl:		no	no
+direct_access:		no	no
 media_changed:		no	no
+unlock_native_capacity:	no	no
 revalidate_disk:	no	no
+getgeo:			no	no
+swap_slot_free_notify:	no	no	(see below)
+
+media_changed, unlock_native_capacity and revalidate_disk are called only from
+check_disk_change().
+
+swap_slot_free_notify is called with swap_lock and sometimes the page lock
+held.
 
-The last two are called only from check_disk_change().
 
 --------------------------- file_operations -------------------------------
 prototypes: