Commit b2e607fe authored by Christoph Hellwig's avatar Christoph Hellwig
Browse files

nvme: refactor the atomic write unit detection 



Move all the code out of nvme_update_disk_info into the helper, and
rename the helper to have a somewhat less clumsy name.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarLuis Chamberlain <mcgrof@kernel.org>
Reviewed-by: default avatarJohn Garry <john.g.garry@oracle.com>
parent dd2c1854

drivers/nvme/host/core.c

+38 −34
Original line number Diff line number Diff line
@@ -2015,21 +2015,51 @@ static void nvme_configure_metadata(struct nvme_ctrl *ctrl, 
}





static void nvme_update_atomic_write_disk_info(struct nvme_ns *ns,

			struct nvme_id_ns *id, struct queue_limits *lim,

			u32 bs, u32 atomic_bs)

static u32 nvme_configure_atomic_write(struct nvme_ns *ns,

		struct nvme_id_ns *id, struct queue_limits *lim, u32 bs)

{

	unsigned int boundary = 0;

	u32 atomic_bs, boundary = 0;



	if (id->nsfeat & NVME_NS_FEAT_ATOMICS && id->nawupf) {

		if (le16_to_cpu(id->nabspf))

	/*

	 * We do not support an offset for the atomic boundaries.

	 */

	if (id->nabo)

		return bs;



	if ((id->nsfeat & NVME_NS_FEAT_ATOMICS) && id->nawupf) {

		/*

		 * Use the per-namespace atomic write unit when available.

		 */

		atomic_bs = (1 + le16_to_cpu(id->nawupf)) * bs;

		if (id->nabspf)

			boundary = (le16_to_cpu(id->nabspf) + 1) * bs;

	} else {

		/*

		 * Use the controller wide atomic write unit.  This sucks

		 * because the limit is defined in terms of logical blocks while

		 * namespaces can have different formats, and because there is

		 * no clear language in the specification prohibiting different

		 * values for different controllers in the subsystem.

		 */

		atomic_bs = (1 + ns->ctrl->awupf) * bs;

	}



	if (!ns->ctrl->subsys->atomic_bs) {

		ns->ctrl->subsys->atomic_bs = atomic_bs;

	} else if (ns->ctrl->subsys->atomic_bs != atomic_bs) {

		dev_err_ratelimited(ns->ctrl->device,

			"%s: Inconsistent Atomic Write Size, Namespace will not be added: Subsystem=%d bytes, Controller/Namespace=%d bytes\n",

			ns->disk ? ns->disk->disk_name : "?",

			ns->ctrl->subsys->atomic_bs,

			atomic_bs);

	}



	lim->atomic_write_hw_max = atomic_bs;

	lim->atomic_write_hw_boundary = boundary;

	lim->atomic_write_hw_unit_min = bs;

	lim->atomic_write_hw_unit_max = rounddown_pow_of_two(atomic_bs);

	lim->features |= BLK_FEAT_ATOMIC_WRITES;

	return atomic_bs;

}



static u32 nvme_max_drv_segments(struct nvme_ctrl *ctrl)
@@ -2067,34 +2097,8 @@ static bool nvme_update_disk_info(struct nvme_ns *ns, struct nvme_id_ns *id, 
		valid = false;

	}



	atomic_bs = phys_bs = bs;

	if (id->nabo == 0) {

		/*

		 * Bit 1 indicates whether NAWUPF is defined for this namespace

		 * and whether it should be used instead of AWUPF. If NAWUPF ==

		 * 0 then AWUPF must be used instead.

		 */

		if (id->nsfeat & NVME_NS_FEAT_ATOMICS && id->nawupf)

			atomic_bs = (1 + le16_to_cpu(id->nawupf)) * bs;

		else

			atomic_bs = (1 + ns->ctrl->awupf) * bs;



		/*

		 * Set subsystem atomic bs.

		 */

		if (ns->ctrl->subsys->atomic_bs) {

			if (atomic_bs != ns->ctrl->subsys->atomic_bs) {

				dev_err_ratelimited(ns->ctrl->device,

					"%s: Inconsistent Atomic Write Size, Namespace will not be added: Subsystem=%d bytes, Controller/Namespace=%d bytes\n",

					ns->disk ? ns->disk->disk_name : "?",

					ns->ctrl->subsys->atomic_bs,

					atomic_bs);

			}

		} else

			ns->ctrl->subsys->atomic_bs = atomic_bs;



		nvme_update_atomic_write_disk_info(ns, id, lim, bs, atomic_bs);

	}

	phys_bs = bs;

	atomic_bs = nvme_configure_atomic_write(ns, id, lim, bs);



	if (id->nsfeat & NVME_NS_FEAT_IO_OPT) {

		/* NPWG = Namespace Preferred Write Granularity */