block: factor out __blkdev_issue_zero_pages()

[mirror_ubuntu-artful-kernel.git] / block / blk-lib.c

diff --git a/block/blk-lib.c b/block/blk-lib.c
index 3fe0aec90597294a15e04b1f89144631b976ab94..4ef942c27ad2bc5c135a69ae712a84c13e3c0a48 100644 (file)
--- 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(bytes >> PAGE_SHIFT, (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->bi_bdev = 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->bi_bdev   = bdev;
-               bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
+               return ret;
 
-               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;
-out:
-       return ret;
+       return __blkdev_issue_zero_pages(bdev, sector, nr_sects, gfp_mask,
+                                        biop);
 }
 EXPORT_SYMBOL(__blkdev_issue_zeroout);