diff options
| -rw-r--r-- | drivers/block/xen-blkback/blkback.c | 54 |
1 files changed, 24 insertions, 30 deletions
diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index 9d2261b02f2..b058de7825f 100644 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -416,12 +416,16 @@ static int xen_blkbk_map(struct blkif_request *req, 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 @@ static void xen_blk_discard(struct xen_blkif *blkif, struct blkif_request *req) 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 @@ __do_block_io_op(struct xen_blkif *blkif) /* 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 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, 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 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, * 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 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, /* 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; } /* |