block/xen-blkfront: Remove invalid comment

Since commit b764915 "xen-blkfront: use a different scatterlist for each
request", biovec has been replaced by scatterlist when copying back the
data during a completion request.

Signed-off-by: Julien Grall <julien.grall@citrix.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit ee4b7179fc9bf19fd22f9d17757a86582c40229e)
Signed-off-by: Elena Ufimtseva <elena.ufimtseva@oracle.com>

diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index 44b33d39441b1235150a87486359cea2f304d329..7a8a73f1fc0462feab5bad706573ff6eb4536ef7 100644 (file)
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -1075,12 +1075,6 @@ static void blkif_completion(struct blk_shadow *s, struct blkfront_info *info,
                s->req.u.indirect.nr_segments : s->req.u.rw.nr_segments;
 
        if (bret->operation == BLKIF_OP_READ && info->feature_persistent) {
-               /*
-                * Copy the data received from the backend into the bvec.
-                * Since bv_offset can be different than 0, and bv_len different
-                * than PAGE_SIZE, we have to keep track of the current offset,
-                * to be sure we are copying the data from the right shared page.
-                */
                for_each_sg(s->sg, sg, nseg, i) {
                        BUG_ON(sg->offset + sg->length > PAGE_SIZE);
                        shared_data = kmap_atomic(