block: simplify submit_bio_checks a bit

Merge a few checks for whole devices vs partitions to streamline the
sanity checks.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/blk-core.c b/block/blk-core.c
index a3a54cd86c9c00ca40d25a5ac186023eb7a00a90..64f69022de96277d932d29e7522789be43dd4c95 100644 (file)
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -692,9 +692,9 @@ static inline bool should_fail_request(struct block_device *part,
 
 #endif /* CONFIG_FAIL_MAKE_REQUEST */
 
-static inline bool bio_check_ro(struct bio *bio, struct block_device *part)
+static inline bool bio_check_ro(struct bio *bio)
 {
-       if (op_is_write(bio_op(bio)) && bdev_read_only(part)) {
+       if (op_is_write(bio_op(bio)) && bdev_read_only(bio->bi_bdev)) {
                char b[BDEVNAME_SIZE];
 
                if (op_is_flush(bio->bi_opf) && !bio_sectors(bio))
@@ -702,7 +702,7 @@ static inline bool bio_check_ro(struct bio *bio, struct block_device *part)
 
                WARN_ONCE(1,
                       "Trying to write to read-only block-device %s (partno %d)\n",
-                       bio_devname(bio, b), part->bd_partno);
+                       bio_devname(bio, b), bio->bi_bdev->bd_partno);
                /* Older lvm-tools actually trigger this */
                return false;
        }
@@ -723,8 +723,9 @@ ALLOW_ERROR_INJECTION(should_fail_bio, ERRNO);
  * This may well happen - the kernel calls bread() without checking the size of
  * the device, e.g., when mounting a file system.
  */
-static inline int bio_check_eod(struct bio *bio, sector_t maxsector)
+static inline int bio_check_eod(struct bio *bio)
 {
+       sector_t maxsector = bdev_nr_sectors(bio->bi_bdev);
        unsigned int nr_sectors = bio_sectors(bio);
 
        if (nr_sectors && maxsector &&
@@ -739,28 +740,20 @@ static inline int bio_check_eod(struct bio *bio, sector_t maxsector)
 /*
  * Remap block n of partition p to block n+start(p) of the disk.
  */
-static inline int blk_partition_remap(struct bio *bio)
+static int blk_partition_remap(struct bio *bio)
 {
        struct block_device *p = bio->bi_bdev;
-       int ret = -EIO;
 
        if (unlikely(should_fail_request(p, bio->bi_iter.bi_size)))
-               goto out;
-       if (unlikely(bio_check_ro(bio, p)))
-               goto out;
-
+               return -EIO;
        if (bio_sectors(bio)) {
-               if (bio_check_eod(bio, bdev_nr_sectors(p)))
-                       goto out;
                bio->bi_iter.bi_sector += p->bd_start_sect;
                trace_block_bio_remap(bio, p->bd_dev,
                                      bio->bi_iter.bi_sector -
                                      p->bd_start_sect);
        }
        bio->bi_bdev = bdev_whole(p);
-       ret = 0;
-out:
-       return ret;
+       return 0;
 }
 
 /*
@@ -820,16 +813,12 @@ static noinline_for_stack bool submit_bio_checks(struct bio *bio)
 
        if (should_fail_bio(bio))
                goto end_io;
-
-       if (bio->bi_bdev->bd_partno) {
-               if (unlikely(blk_partition_remap(bio)))
-                       goto end_io;
-       } else {
-               if (unlikely(bio_check_ro(bio, bdev_whole(bdev))))
-                       goto end_io;
-               if (unlikely(bio_check_eod(bio, get_capacity(bdev->bd_disk))))
-                       goto end_io;
-       }
+       if (unlikely(bio_check_ro(bio)))
+               goto end_io;
+       if (unlikely(bio_check_eod(bio)))
+               goto end_io;
+       if (bio->bi_bdev->bd_partno && unlikely(blk_partition_remap(bio)))
+               goto end_io;
 
        /*
         * Filter flush bio's early so that bio based drivers without flush