From 4dda41d3d76747414586a4bad5615b550e0986b1 Mon Sep 17 00:00:00 2001 From: Alex Elder Date: Wed, 20 Feb 2013 21:59:33 -0600 Subject: [PATCH] rbd: ignore zero-length requests The old request code simply ignored zero-length requests. We should still operate that same way to avoid any changes in behavior. We can implement handling for special zero-length requests separately (see http://tracker.ceph.com/issues/4236). Add some assertions based on this new constraint. This resolves: http://tracker.ceph.com/issues/4237 Signed-off-by: Alex Elder Reviewed-by: Josh Durgin --- drivers/block/rbd.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index b0eea3eaee93..3cc003b26610 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -1560,6 +1560,7 @@ static int rbd_img_request_fill_bio(struct rbd_img_request *img_request, image_offset = img_request->offset; rbd_assert(image_offset == bio_list->bi_sector << SECTOR_SHIFT); resid = img_request->length; + rbd_assert(resid > 0); while (resid) { const char *object_name; unsigned int clone_size; @@ -1627,8 +1628,10 @@ static void rbd_img_obj_callback(struct rbd_obj_request *obj_request) bool more = true; img_request = obj_request->img_request; + rbd_assert(img_request != NULL); rbd_assert(img_request->rq != NULL); + rbd_assert(img_request->obj_request_count > 0); rbd_assert(which != BAD_WHICH); rbd_assert(which < img_request->obj_request_count); rbd_assert(which >= img_request->next_completion); @@ -1918,6 +1921,19 @@ static void rbd_request_fn(struct request_queue *q) /* Ignore any non-FS requests that filter through. */ if (rq->cmd_type != REQ_TYPE_FS) { + dout("%s: non-fs request type %d\n", __func__, + (int) rq->cmd_type); + __blk_end_request_all(rq, 0); + continue; + } + + /* Ignore/skip any zero-length requests */ + + offset = (u64) blk_rq_pos(rq) << SECTOR_SHIFT; + length = (u64) blk_rq_bytes(rq); + + if (!length) { + dout("%s: zero-length request\n", __func__); __blk_end_request_all(rq, 0); continue; } @@ -1947,9 +1963,6 @@ static void rbd_request_fn(struct request_queue *q) goto end_request; } - offset = (u64) blk_rq_pos(rq) << SECTOR_SHIFT; - length = (u64) blk_rq_bytes(rq); - result = -EINVAL; if (WARN_ON(offset && length > U64_MAX - offset + 1)) goto end_request; /* Shouldn't happen */