block: split discard into aligned requests

[linux-2.6-block.git] / include / linux / blkdev.h

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 4e72a9d48232d513b5b2fe44d973de8dfeb1e9e4..281516ae8b4ef37256af453e00c1c098d315f769 100644 (file)
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1139,6 +1139,16 @@ static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector
                & (lim->discard_granularity - 1);
 }
 
+static inline int bdev_discard_alignment(struct block_device *bdev)
+{
+       struct request_queue *q = bdev_get_queue(bdev);
+
+       if (bdev != bdev->bd_contains)
+               return bdev->bd_part->discard_alignment;
+
+       return q->limits.discard_alignment;
+}
+
 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q)
 {
        if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1)