From 976222e05ea5a9959ccf880d7a24efbf79b3c6cf Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Fri, 15 Apr 2011 11:38:29 -0400 Subject: [PATCH] xen/blkback: Move the check for misaligned I/O higher. We move it up higher to be in same loop that actually computes the sector number. This way, all of the code that deals with verifying that the request is correct is all done before we do any of the page mapping, I/O submission, etc. Signed-off-by: Konrad Rzeszutek Wilk --- drivers/xen/blkback/blkback.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/drivers/xen/blkback/blkback.c b/drivers/xen/blkback/blkback.c index 211b2005f963..9598e0fd0f9e 100644 --- a/drivers/xen/blkback/blkback.c +++ b/drivers/xen/blkback/blkback.c @@ -521,6 +521,13 @@ static void dispatch_rw_block_io(struct blkif_st *blkif, (req->u.rw.seg[i].last_sect < req->u.rw.seg[i].first_sect)) goto fail_response; preq.nr_sects += seg[i].nsec; + + if (((int)preq.sector_number|(int)seg[i].nsec) & + ((bdev_logical_block_size(preq.bdev) >> 9) - 1)) { + DPRINTK("Misaligned I/O request from domain %d", + blkif->domid); + goto fail_response; + } } if (vbd_translate(&preq, blkif, operation) != 0) { @@ -542,13 +549,6 @@ static void dispatch_rw_block_io(struct blkif_st *blkif, blkif_get(blkif); for (i = 0; i < nseg; i++) { - if (((int)preq.sector_number|(int)seg[i].nsec) & - ((bdev_logical_block_size(preq.bdev) >> 9) - 1)) { - DPRINTK("Misaligned I/O request from domain %d", - blkif->domid); - goto fail_put_bio; - } - while ((bio == NULL) || (bio_add_page(bio, blkbk->pending_page(pending_req, i),