Commit 20469a37 authored Jan 17, 2018 by Keith Busch Committed by Jens Axboe Jan 17, 2018

nvme-pci: check segement valid for SGL use



The driver needs to verify there is a payload with a command before
seeing if it should use SGLs to map it.

Fixes: 955b1b5a ("nvme-pci: move use_sgl initialization to nvme_init_iod()")
Reported-by: Paul Menzel <pmenzel+linux-nvme@molgen.mpg.de>
Reviewed-by: Paul Menzel <pmenzel+linux-nvme@molgen.mpg.de>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

parent 32835a07

drivers/nvme/host/pci.c

+5 −2

Original line number	Diff line number	Diff line
		@@ -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;