From: Keith Busch <[email protected]>
The driver needs to verify there is a payload with a command before
seeing if it should use SGLs to map it.
Fixes: 955b1b5a00ba ("nvme-pci: move use_sgl initialization to nvme_init_iod()")
Reported-by: Paul Menzel <[email protected]>
Reviewed-by: Paul Menzel <[email protected]>
Signed-off-by: Keith Busch <[email protected]>
Signed-off-by: Christoph Hellwig <[email protected]>
---
drivers/nvme/host/pci.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index d53550e612bc..a7e94cc3c70e 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -451,10 +451,13 @@ static void **nvme_pci_iod_list(struct request *req)
static inline bool nvme_pci_use_sgls(struct nvme_dev *dev, struct request *req)
{
struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
+ int nseg = blk_rq_nr_phys_segments(req);
unsigned int avg_seg_size;
- avg_seg_size = DIV_ROUND_UP(blk_rq_payload_bytes(req),
- blk_rq_nr_phys_segments(req));
+ if (nseg == 0)
+ return false;
+
+ avg_seg_size = DIV_ROUND_UP(blk_rq_payload_bytes(req), nseg);
if (!(dev->ctrl.sgls & ((1 << 0) | (1 << 1))))
return false;
--
2.14.2
