[PATCH] Add block_device_operations.getgeo block device method

HDIO_GETGEO is implemented in most block drivers, and all of them have to
duplicate the code to copy the structure to userspace, as well as getting
the start sector.  This patch moves that to common code [1] and adds a
->getgeo method to fill out the raw kernel hd_geometry structure.  For many
drivers this means ->ioctl can go away now.

[1] the s390 block drivers are odd in this respect.  xpram sets ->start
    to 4 always which seems more than odd, and the dasd driver shifts
    the start offset around, probably because of it's non-standard
    sector size.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Jens Axboe <axboe@suse.de>
Cc: <mike.miller@hp.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Cc: Bartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Cc: Markus Lidel <Markus.Lidel@shadowconnect.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 11 insertions, 19 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 1b76fb2..e423a16 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -3598,12 +3598,21 @@ static int set_disk_faulty(mddev_t *mddev, dev_t dev)
 	return 0;
 }
 
+static int md_getgeo(struct block_device *bdev, struct hd_geometry *geo)
+{
+	mddev_t *mddev = bdev->bd_disk->private_data;
+
+	geo->heads = 2;
+	geo->sectors = 4;
+	geo->cylinders = get_capacity(mddev->gendisk) / 8;
+	return 0;
+}
+
 static int md_ioctl(struct inode *inode, struct file *file,
 			unsigned int cmd, unsigned long arg)
 {
 	int err = 0;
 	void __user *argp = (void __user *)arg;
-	struct hd_geometry __user *loc = argp;
 	mddev_t *mddev = NULL;
 
 	if (!capable(CAP_SYS_ADMIN))
@@ -3765,24 +3774,6 @@ static int md_ioctl(struct inode *inode, struct file *file,
 	 * 4 sectors (with a BIG number of cylinders...). This drives
 	 * dosfs just mad... ;-)
 	 */
-		case HDIO_GETGEO:
-			if (!loc) {
-				err = -EINVAL;
-				goto abort_unlock;
-			}
-			err = put_user (2, (char __user *) &loc->heads);
-			if (err)
-				goto abort_unlock;
-			err = put_user (4, (char __user *) &loc->sectors);
-			if (err)
-				goto abort_unlock;
-			err = put_user(get_capacity(mddev->gendisk)/8,
-					(short __user *) &loc->cylinders);
-			if (err)
-				goto abort_unlock;
-			err = put_user (get_start_sect(inode->i_bdev),
-						(long __user *) &loc->start);
-			goto done_unlock;
 	}
 
 	/*
@@ -3911,6 +3902,7 @@ static struct block_device_operations md_fops =
 	.open		= md_open,
 	.release	= md_release,
 	.ioctl		= md_ioctl,
+	.getgeo		= md_getgeo,
 	.media_changed	= md_media_changed,
 	.revalidate_disk= md_revalidate,
 };