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, 6 insertions, 5 deletions

diff --git a/fs/partitions/mac.c b/fs/partitions/mac.c
index d4a0fad3563b..13e27b0082f2 100644
--- a/fs/partitions/mac.c
+++ b/fs/partitions/mac.c
@@ -27,7 +27,7 @@ static inline void mac_fix_string(char *stg, int len)
                 stg[i] = 0;
 }
 
-int mac_partition(struct parsed_partitions *state, struct block_device *bdev)
+int mac_partition(struct parsed_partitions *state)
 {
         int slot = 1;
         Sector sect;
@@ -42,7 +42,7 @@ int mac_partition(struct parsed_partitions *state, struct block_device *bdev)
         struct mac_driver_desc *md;
 
         /* Get 0th block and look at the first partition map entry. */
-        md = (struct mac_driver_desc *) read_dev_sector(bdev, 0, &sect);
+        md = read_part_sector(state, 0, &sect);
         if (!md)
                 return -1;
         if (be16_to_cpu(md->signature) != MAC_DRIVER_MAGIC) {
@@ -51,7 +51,7 @@ int mac_partition(struct parsed_partitions *state, struct block_device *bdev)
         }
         secsize = be16_to_cpu(md->block_size);
         put_dev_sector(sect);
-        data = read_dev_sector(bdev, secsize/512, &sect);
+        data = read_part_sector(state, secsize/512, &sect);
         if (!data)
                 return -1;
         part = (struct mac_partition *) (data + secsize%512);
@@ -64,7 +64,7 @@ int mac_partition(struct parsed_partitions *state, struct block_device *bdev)
         for (blk = 1; blk <= blocks_in_map; ++blk) {
                 int pos = blk * secsize;
                 put_dev_sector(sect);
-                data = read_dev_sector(bdev, pos/512, &sect);
+                data = read_part_sector(state, pos/512, &sect);
                 if (!data)
                         return -1;
                 part = (struct mac_partition *) (data + pos%512);
@@ -123,7 +123,8 @@ int mac_partition(struct parsed_partitions *state, struct block_device *bdev)
         }
 #ifdef CONFIG_PPC_PMAC
         if (found_root_goodness)
-                note_bootable_part(bdev->bd_dev, found_root, found_root_goodness);
+                note_bootable_part(state->bdev->bd_dev, found_root,
+                                   found_root_goodness);
 #endif
 
         put_dev_sector(sect);