Linux 3.2.82

[pandora-kernel.git] / drivers / md / dm-io.c

diff --git a/drivers/md/dm-io.c b/drivers/md/dm-io.c
index 629083b..b8ed01b 100644 (file)
--- a/drivers/md/dm-io.c
+++ b/drivers/md/dm-io.c
@@ -299,11 +299,15 @@ static void do_region(int rw, unsigned region, struct dm_io_region *where,
        sector_t remaining = where->count;
        struct request_queue *q = bdev_get_queue(where->bdev);
        sector_t discard_sectors;
+       unsigned int uninitialized_var(special_cmd_max_sectors);
 
        /* Reject unsupported discard requests */
-       if ((rw & REQ_DISCARD) && !blk_queue_discard(q)) {
-               dec_count(io, region, -EOPNOTSUPP);
-               return;
+       if (rw & REQ_DISCARD) {
+               special_cmd_max_sectors = q->limits.max_discard_sectors;
+               if (special_cmd_max_sectors == 0) {
+                       dec_count(io, region, -EOPNOTSUPP);
+                       return;
+               }
        }
 
        /*
@@ -328,7 +332,7 @@ static void do_region(int rw, unsigned region, struct dm_io_region *where,
                store_io_and_region_in_bio(bio, io, region);
 
                if (rw & REQ_DISCARD) {
-                       discard_sectors = min_t(sector_t, q->limits.max_discard_sectors, remaining);
+                       discard_sectors = min_t(sector_t, special_cmd_max_sectors, remaining);
                        bio->bi_size = discard_sectors << SECTOR_SHIFT;
                        remaining -= discard_sectors;
                } else while (remaining) {