blkdev: Submit discard bio in batches in blkdev_issue_discard()

[linux-2.6-block.git] / block / blk-lib.c

diff --git a/block/blk-lib.c b/block/blk-lib.c
index 25de73e4759b82d624c2a89b545baf6ea859f624..9260cb0b209b66f316aac1e21d2211d1ee6f7f0d 100644 (file)
--- a/block/blk-lib.c
+++ b/block/blk-lib.c
@@ -9,17 +9,23 @@
 
 #include "blk.h"
 
-static void blkdev_discard_end_io(struct bio *bio, int err)
+struct bio_batch {
+       atomic_t                done;
+       unsigned long           flags;
+       struct completion       *wait;
+};
+
+static void bio_batch_end_io(struct bio *bio, int err)
 {
+       struct bio_batch *bb = bio->bi_private;
+
        if (err) {
                if (err == -EOPNOTSUPP)
-                       set_bit(BIO_EOPNOTSUPP, &bio->bi_flags);
-               clear_bit(BIO_UPTODATE, &bio->bi_flags);
+                       set_bit(BIO_EOPNOTSUPP, &bb->flags);
+               clear_bit(BIO_UPTODATE, &bb->flags);
        }
-
-       if (bio->bi_private)
-               complete(bio->bi_private);
-
+       if (atomic_dec_and_test(&bb->done))
+               complete(bb->wait);
        bio_put(bio);
 }
 
@@ -41,6 +47,7 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
        struct request_queue *q = bdev_get_queue(bdev);
        int type = REQ_WRITE | REQ_DISCARD;
        unsigned int max_discard_sectors;
+       struct bio_batch bb;
        struct bio *bio;
        int ret = 0;
 
@@ -67,7 +74,11 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
                type |= REQ_SECURE;
        }
 
-       while (nr_sects && !ret) {
+       atomic_set(&bb.done, 1);
+       bb.flags = 1 << BIO_UPTODATE;
+       bb.wait = &wait;
+
+       while (nr_sects) {
                bio = bio_alloc(gfp_mask, 1);
                if (!bio) {
                        ret = -ENOMEM;
@@ -75,9 +86,9 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
                }
 
                bio->bi_sector = sector;
-               bio->bi_end_io = blkdev_discard_end_io;
+               bio->bi_end_io = bio_batch_end_io;
                bio->bi_bdev = bdev;
-               bio->bi_private = &wait;
+               bio->bi_private = &bb;
 
                if (nr_sects > max_discard_sectors) {
                        bio->bi_size = max_discard_sectors << 9;
@@ -88,45 +99,23 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
                        nr_sects = 0;
                }
 
-               bio_get(bio);
+               atomic_inc(&bb.done);
                submit_bio(type, bio);
+       }
 
+       /* Wait for bios in-flight */
+       if (!atomic_dec_and_test(&bb.done))
                wait_for_completion(&wait);
 
-               if (bio_flagged(bio, BIO_EOPNOTSUPP))
-                       ret = -EOPNOTSUPP;
-               else if (!bio_flagged(bio, BIO_UPTODATE))
-                       ret = -EIO;
-               bio_put(bio);
-       }
+       if (test_bit(BIO_EOPNOTSUPP, &bb.flags))
+               ret = -EOPNOTSUPP;
+       else if (!test_bit(BIO_UPTODATE, &bb.flags))
+               ret = -EIO;
 
        return ret;
 }
 EXPORT_SYMBOL(blkdev_issue_discard);
 
-struct bio_batch
-{
-       atomic_t                done;
-       unsigned long           flags;
-       struct completion       *wait;
-};
-
-static void bio_batch_end_io(struct bio *bio, int err)
-{
-       struct bio_batch *bb = bio->bi_private;
-
-       if (err) {
-               if (err == -EOPNOTSUPP)
-                       set_bit(BIO_EOPNOTSUPP, &bb->flags);
-               else
-                       clear_bit(BIO_UPTODATE, &bb->flags);
-       }
-       if (bb)
-               if (atomic_dec_and_test(&bb->done))
-                       complete(bb->wait);
-       bio_put(bio);
-}
-
 /**
  * blkdev_issue_zeroout - generate number of zero filed write bios
  * @bdev:      blockdev to issue