block: use struct parsed_partitions *state universally in partition check code

Make the following changes to partition check code.

* Add ->bdev to struct parsed_partitions.

* Introduce read_part_sector() which is a simple wrapper around
  read_dev_sector() which takes struct parsed_partitions *state
  instead of @bdev.

* For functions which used to take @state and @bdev, drop @bdev.  For
  functions which used to take @bdev, replace it with @state.

* While updating, drop superflous checks on NULL state/bdev in ldm.c.

This cleans up the API a bit and enables better handling of IO errors
during partition check as the generic partition check code now has
much better visibility into what went wrong in the low level code
paths.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ben Hutchings <ben@decadent.org.uk>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/fs/partitions/sgi.c b/fs/partitions/sgi.c
index ed5ac83fe83a..43b1df9aa16c 100644
--- a/fs/partitions/sgi.c
+++ b/fs/partitions/sgi.c
@@ -27,7 +27,7 @@ struct sgi_disklabel {
 	__be32 _unused1;			/* Padding */
 };
 
-int sgi_partition(struct parsed_partitions *state, struct block_device *bdev)
+int sgi_partition(struct parsed_partitions *state)
 {
 	int i, csum;
 	__be32 magic;
@@ -39,7 +39,7 @@ int sgi_partition(struct parsed_partitions *state, struct block_device *bdev)
 	struct sgi_partition *p;
 	char b[BDEVNAME_SIZE];
 
-	label = (struct sgi_disklabel *) read_dev_sector(bdev, 0, &sect);
+	label = read_part_sector(state, 0, &sect);
 	if (!label)
 		return -1;
 	p = &label->partitions[0];
@@ -57,7 +57,7 @@ int sgi_partition(struct parsed_partitions *state, struct block_device *bdev)
 	}
 	if(csum) {
 		printk(KERN_WARNING "Dev %s SGI disklabel: csum bad, label corrupted\n",
-		       bdevname(bdev, b));
+		       bdevname(state->bdev, b));
 		put_dev_sector(sect);
 		return 0;
 	}