block: factor out __blkdev_issue_zero_pages()

blkdev_issue_zeroout() will use this in !BLKDEV_ZERO_NOFALLBACK case.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 37 insertions, 26 deletions

diff --git a/block/blk-lib.c b/block/blk-lib.c
index 62240f8832ca..9d2ab8bba52a 100644
--- a/block/blk-lib.c
+++ b/block/blk-lib.c
@@ -274,6 +274,40 @@ static unsigned int __blkdev_sectors_to_bio_pages(sector_t nr_sects)
         return min(pages, (sector_t)BIO_MAX_PAGES);
 }
 
+static int __blkdev_issue_zero_pages(struct block_device *bdev,
+                sector_t sector, sector_t nr_sects, gfp_t gfp_mask,
+                struct bio **biop)
+{
+        struct request_queue *q = bdev_get_queue(bdev);
+        struct bio *bio = *biop;
+        int bi_size = 0;
+        unsigned int sz;
+
+        if (!q)
+                return -ENXIO;
+
+        while (nr_sects != 0) {
+                bio = next_bio(bio, __blkdev_sectors_to_bio_pages(nr_sects),
+                               gfp_mask);
+                bio->bi_iter.bi_sector = sector;
+                bio_set_dev(bio, bdev);
+                bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
+
+                while (nr_sects != 0) {
+                        sz = min((sector_t) PAGE_SIZE, nr_sects << 9);
+                        bi_size = bio_add_page(bio, ZERO_PAGE(0), sz, 0);
+                        nr_sects -= bi_size >> 9;
+                        sector += bi_size >> 9;
+                        if (bi_size < sz)
+                                break;
+                }
+                cond_resched();
+        }
+
+        *biop = bio;
+        return 0;
+}
+
 /**
  * __blkdev_issue_zeroout - generate number of zero filed write bios
  * @bdev:       blockdev to issue
@@ -304,9 +338,6 @@ int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
                 unsigned flags)
 {
         int ret;
-        int bi_size = 0;
-        struct bio *bio = *biop;
-        unsigned int sz;
         sector_t bs_mask;
 
         bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
@@ -316,30 +347,10 @@ int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
         ret = __blkdev_issue_write_zeroes(bdev, sector, nr_sects, gfp_mask,
                         biop, flags);
         if (ret != -EOPNOTSUPP || (flags & BLKDEV_ZERO_NOFALLBACK))
-                goto out;
-
-        ret = 0;
-        while (nr_sects != 0) {
-                bio = next_bio(bio, __blkdev_sectors_to_bio_pages(nr_sects),
-                               gfp_mask);
-                bio->bi_iter.bi_sector = sector;
-                bio_set_dev(bio, bdev);
-                bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
-
-                while (nr_sects != 0) {
-                        sz = min((sector_t) PAGE_SIZE, nr_sects << 9);
-                        bi_size = bio_add_page(bio, ZERO_PAGE(0), sz, 0);
-                        nr_sects -= bi_size >> 9;
-                        sector += bi_size >> 9;
-                        if (bi_size < sz)
-                                break;
-                }
-                cond_resched();
-        }
+                return ret;
 
-        *biop = bio;
-out:
-        return ret;
+        return __blkdev_issue_zero_pages(bdev, sector, nr_sects, gfp_mask,
+                                         biop);
 }
 EXPORT_SYMBOL(__blkdev_issue_zeroout);