Commit 4d6b1c95 authored by Revanth Rajashekar's avatar Revanth Rajashekar Committed by Christoph Hellwig
Browse files

nvme: check the PRINFO bit before deciding the host buffer length 



According to NVMe spec v1.4, section 8.3.1, the PRINFO bit and
the metadata size play a vital role in deteriming the host buffer size.

If PRIFNO bit is set and MS==8, the host doesn't add the metadata buffer,
instead the controller adds it.

Signed-off-by: default avatarRevanth Rajashekar <revanth.rajashekar@intel.com>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
parent b4f66425

drivers/nvme/host/core.c

+15 −2
Original line number Diff line number Diff line
@@ -1543,8 +1543,21 @@ static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio) 
	}



	length = (io.nblocks + 1) << ns->lba_shift;



	if ((io.control & NVME_RW_PRINFO_PRACT) &&

	    ns->ms == sizeof(struct t10_pi_tuple)) {

		/*

		 * Protection information is stripped/inserted by the

		 * controller.

		 */

		if (nvme_to_user_ptr(io.metadata))

			return -EINVAL;

		meta_len = 0;

		metadata = NULL;

	} else {

		meta_len = (io.nblocks + 1) * ns->ms;

		metadata = nvme_to_user_ptr(io.metadata);

	}



	if (ns->features & NVME_NS_EXT_LBAS) {

		length += meta_len;