xen/blkback: Move processing of BLKIF_OP_DISCARD from dispatch_rw_block_io
.. and move it to its own function that will deal with the
discard operation.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c
index 9d2261b..b058de7 100644
--- a/drivers/block/xen-blkback/blkback.c
+++ b/drivers/block/xen-blkback/blkback.c
@@ -416,12 +416,16 @@
return ret;
}
-static void xen_blk_discard(struct xen_blkif *blkif, struct blkif_request *req)
+static int dispatch_discard_io(struct xen_blkif *blkif,
+ struct blkif_request *req)
{
int err = 0;
int status = BLKIF_RSP_OKAY;
struct block_device *bdev = blkif->vbd.bdev;
+ blkif->st_ds_req++;
+
+ xen_blkif_get(blkif);
if (blkif->blk_backend_type == BLKIF_BACKEND_PHY) {
unsigned long secure = (blkif->vbd.discard_secure &&
(req->u.discard.flag & BLKIF_DISCARD_SECURE)) ?
@@ -453,6 +457,8 @@
status = BLKIF_RSP_ERROR;
make_response(blkif, req->u.discard.id, req->operation, status);
+ xen_blkif_put(blkif);
+ return err;
}
static void xen_blk_drain_io(struct xen_blkif *blkif)
@@ -576,8 +582,11 @@
/* Apply all sanity checks to /private copy/ of request. */
barrier();
-
- if (dispatch_rw_block_io(blkif, &req, pending_req))
+ if (unlikely(req.operation == BLKIF_OP_DISCARD)) {
+ free_req(pending_req);
+ if (dispatch_discard_io(blkif, &req))
+ break;
+ } else if (dispatch_rw_block_io(blkif, &req, pending_req))
break;
/* Yield point for this unbounded loop. */
@@ -636,24 +645,16 @@
blkif->st_f_req++;
operation = WRITE_FLUSH;
break;
- case BLKIF_OP_DISCARD:
- blkif->st_ds_req++;
- operation = REQ_DISCARD;
- break;
default:
operation = 0; /* make gcc happy */
goto fail_response;
break;
}
- if (unlikely(operation == REQ_DISCARD))
- nseg = 0;
- else
- /* Check that the number of segments is sane. */
- nseg = req->u.rw.nr_segments;
+ /* Check that the number of segments is sane. */
+ nseg = req->u.rw.nr_segments;
- if (unlikely(nseg == 0 && operation != WRITE_FLUSH &&
- operation != REQ_DISCARD) ||
+ if (unlikely(nseg == 0 && operation != WRITE_FLUSH) ||
unlikely(nseg > BLKIF_MAX_SEGMENTS_PER_REQUEST)) {
pr_debug(DRV_PFX "Bad number of segments in request (%d)\n",
nseg);
@@ -714,7 +715,7 @@
* the hypercall to unmap the grants - that is all done in
* xen_blkbk_unmap.
*/
- if (nseg && xen_blkbk_map(req, pending_req, seg))
+ if (xen_blkbk_map(req, pending_req, seg))
goto fail_flush;
/*
@@ -746,23 +747,16 @@
/* This will be hit if the operation was a flush or discard. */
if (!bio) {
- BUG_ON(operation != WRITE_FLUSH && operation != REQ_DISCARD);
+ BUG_ON(operation != WRITE_FLUSH);
- if (operation == WRITE_FLUSH) {
- bio = bio_alloc(GFP_KERNEL, 0);
- if (unlikely(bio == NULL))
- goto fail_put_bio;
+ bio = bio_alloc(GFP_KERNEL, 0);
+ if (unlikely(bio == NULL))
+ goto fail_put_bio;
- biolist[nbio++] = bio;
- bio->bi_bdev = preq.bdev;
- bio->bi_private = pending_req;
- bio->bi_end_io = end_block_io_op;
- } else if (operation == REQ_DISCARD) {
- xen_blk_discard(blkif, req);
- xen_blkif_put(blkif);
- free_req(pending_req);
- return 0;
- }
+ biolist[nbio++] = bio;
+ bio->bi_bdev = preq.bdev;
+ bio->bi_private = pending_req;
+ bio->bi_end_io = end_block_io_op;
}
/*