block: unexport read_dev_sector and put_dev_sector

read_dev_sector and put_dev_sector are now only used by the partition
parsing code.  Remove the export for read_dev_sector and merge it into
the only caller.  Clean the mess up a bit by using goto labels and
the SECTOR_SHIFT constant.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/partition-generic.c

@@ -484,22 +484,29 @@ int blk_add_partitions(struct gendisk *disk, struct block_device *bdev)
 	return ret;
 }
 
-unsigned char *read_dev_sector(struct block_device *bdev, sector_t n, Sector *p)
+void *read_part_sector(struct parsed_partitions *state, sector_t n, Sector *p)
 {
-	struct address_space *mapping = bdev->bd_inode->i_mapping;
+	struct address_space *mapping = state->bdev->bd_inode->i_mapping;
 	struct page *page;
 
-	page = read_mapping_page(mapping, (pgoff_t)(n >> (PAGE_SHIFT-9)), NULL);
-	if (!IS_ERR(page)) {
-		if (PageError(page))
-			goto fail;
-		p->v = page;
-		return (unsigned char *)page_address(page) +  ((n & ((1 << (PAGE_SHIFT - 9)) - 1)) << 9);
-fail:
-		put_page(page);
+	if (n >= get_capacity(state->bdev->bd_disk)) {
+		state->access_beyond_eod = true;
+		return NULL;
 	}
+
+	page = read_mapping_page(mapping,
+			(pgoff_t)(n >> (PAGE_SHIFT - 9)), NULL);
+	if (IS_ERR(page))
+		goto out;
+	if (PageError(page))
+		goto out_put_page;
+
+	p->v = page;
+	return (unsigned char *)page_address(page) +
+			((n & ((1 << (PAGE_SHIFT - 9)) - 1)) << SECTOR_SHIFT);
+out_put_page:
+	put_page(page);
+out:
 	p->v = NULL;
 	return NULL;
 }
-
-EXPORT_SYMBOL(read_dev_sector);

block/partitions/check.h

@@ -28,14 +28,14 @@ void free_partitions(struct parsed_partitions *state);
 struct parsed_partitions *
 check_partition(struct gendisk *, struct block_device *);
 
-static inline void *read_part_sector(struct parsed_partitions *state,
-				     sector_t n, Sector *p)
+typedef struct {
+	struct page *v;
+} Sector;
+
+void *read_part_sector(struct parsed_partitions *state, sector_t n, Sector *p);
+static inline void put_dev_sector(Sector p)
 {
-	if (n >= get_capacity(state->bdev->bd_disk)) {
-		state->access_beyond_eod = true;
-		return NULL;
-	}
-	return read_dev_sector(state->bdev, n, p);
+	put_page(p.v);
 }
 
 static inline void

include/linux/blkdev.h

@@ -1484,15 +1484,6 @@ static inline unsigned int block_size(struct block_device *bdev)
 	return bdev->bd_block_size;
 }
 
-typedef struct {struct page *v;} Sector;
-
-unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
-
-static inline void put_dev_sector(Sector p)
-{
-	put_page(p.v);
-}
-
 int kblockd_schedule_work(struct work_struct *work);
 int kblockd_mod_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);