[mirror_ubuntu-artful-kernel.git] / drivers / nvme / target / io-cmd.c

/*
 * NVMe I/O command implementation.
 * Copyright (c) 2015-2016 HGST, a Western Digital Company.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 */
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/blkdev.h>
#include <linux/module.h>
#include "nvmet.h"

static void nvmet_bio_done(struct bio *bio)
{
	struct nvmet_req *req = bio->bi_private;

	nvmet_req_complete(req,
		bio->bi_error ? NVME_SC_INTERNAL | NVME_SC_DNR : 0);

	if (bio != &req->inline_bio)
		bio_put(bio);
}

static inline u32 nvmet_rw_len(struct nvmet_req *req)
{
	return ((u32)le16_to_cpu(req->cmd->rw.length) + 1) <<
			req->ns->blksize_shift;
}

static void nvmet_inline_bio_init(struct nvmet_req *req)
{
	struct bio *bio = &req->inline_bio;

	bio_init(bio);
	bio->bi_max_vecs = NVMET_MAX_INLINE_BIOVEC;
	bio->bi_io_vec = req->inline_bvec;
}

static void nvmet_execute_rw(struct nvmet_req *req)
{
	int sg_cnt = req->sg_cnt;
	struct scatterlist *sg;
	struct bio *bio;
	sector_t sector;
	blk_qc_t cookie;
	int op, op_flags = 0, i;

	if (!req->sg_cnt) {
		nvmet_req_complete(req, 0);
		return;
	}

	if (req->cmd->rw.opcode == nvme_cmd_write) {
		op = REQ_OP_WRITE;
		op_flags = REQ_SYNC | REQ_IDLE;
		if (req->cmd->rw.control & cpu_to_le16(NVME_RW_FUA))
			op_flags |= REQ_FUA;
	} else {
		op = REQ_OP_READ;
	}

	sector = le64_to_cpu(req->cmd->rw.slba);
	sector <<= (req->ns->blksize_shift - 9);

	nvmet_inline_bio_init(req);
	bio = &req->inline_bio;
	bio->bi_bdev = req->ns->bdev;
	bio->bi_iter.bi_sector = sector;
	bio->bi_private = req;
	bio->bi_end_io = nvmet_bio_done;
	bio_set_op_attrs(bio, op, op_flags);

	for_each_sg(req->sg, sg, req->sg_cnt, i) {
		while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
				!= sg->length) {
			struct bio *prev = bio;

			bio = bio_alloc(GFP_KERNEL, min(sg_cnt, BIO_MAX_PAGES));
			bio->bi_bdev = req->ns->bdev;
			bio->bi_iter.bi_sector = sector;
			bio_set_op_attrs(bio, op, op_flags);

			bio_chain(bio, prev);
			cookie = submit_bio(prev);
		}

		sector += sg->length >> 9;
		sg_cnt--;
	}

	cookie = submit_bio(bio);

	blk_poll(bdev_get_queue(req->ns->bdev), cookie);
}

static void nvmet_execute_flush(struct nvmet_req *req)
{
	struct bio *bio;

	nvmet_inline_bio_init(req);
	bio = &req->inline_bio;

	bio->bi_bdev = req->ns->bdev;
	bio->bi_private = req;
	bio->bi_end_io = nvmet_bio_done;
	bio->bi_opf = REQ_OP_WRITE | REQ_PREFLUSH;

	submit_bio(bio);
}

static u16 nvmet_discard_range(struct nvmet_ns *ns,
		struct nvme_dsm_range *range, struct bio **bio)
{
	if (__blkdev_issue_discard(ns->bdev,
			le64_to_cpu(range->slba) << (ns->blksize_shift - 9),
			le32_to_cpu(range->nlb) << (ns->blksize_shift - 9),
			GFP_KERNEL, 0, bio))
		return NVME_SC_INTERNAL | NVME_SC_DNR;
	return 0;
}

static void nvmet_execute_discard(struct nvmet_req *req)
{
	struct nvme_dsm_range range;
	struct bio *bio = NULL;
	int i;
	u16 status;

	for (i = 0; i <= le32_to_cpu(req->cmd->dsm.nr); i++) {
		status = nvmet_copy_from_sgl(req, i * sizeof(range), &range,
				sizeof(range));
		if (status)
			break;

		status = nvmet_discard_range(req->ns, &range, &bio);
		if (status)
			break;
	}

	if (bio) {
		bio->bi_private = req;
		bio->bi_end_io = nvmet_bio_done;
		if (status) {
			bio->bi_error = -EIO;
			bio_endio(bio);
		} else {
			submit_bio(bio);
		}
	} else {
		nvmet_req_complete(req, status);
	}
}

static void nvmet_execute_dsm(struct nvmet_req *req)
{
	switch (le32_to_cpu(req->cmd->dsm.attributes)) {
	case NVME_DSMGMT_AD:
		nvmet_execute_discard(req);
		return;
	case NVME_DSMGMT_IDR:
	case NVME_DSMGMT_IDW:
	default:
		/* Not supported yet */
		nvmet_req_complete(req, 0);
		return;
	}
}

int nvmet_parse_io_cmd(struct nvmet_req *req)
{
	struct nvme_command *cmd = req->cmd;

	if (unlikely(!(req->sq->ctrl->cc & NVME_CC_ENABLE))) {
		pr_err("nvmet: got io cmd %d while CC.EN == 0\n",
				cmd->common.opcode);
		req->ns = NULL;
		return NVME_SC_CMD_SEQ_ERROR | NVME_SC_DNR;
	}

	if (unlikely(!(req->sq->ctrl->csts & NVME_CSTS_RDY))) {
		pr_err("nvmet: got io cmd %d while CSTS.RDY == 0\n",
				cmd->common.opcode);
		req->ns = NULL;
		return NVME_SC_CMD_SEQ_ERROR | NVME_SC_DNR;
	}

	req->ns = nvmet_find_namespace(req->sq->ctrl, cmd->rw.nsid);
	if (!req->ns)
		return NVME_SC_INVALID_NS | NVME_SC_DNR;

	switch (cmd->common.opcode) {
	case nvme_cmd_read:
	case nvme_cmd_write:
		req->execute = nvmet_execute_rw;
		req->data_len = nvmet_rw_len(req);
		return 0;
	case nvme_cmd_flush:
		req->execute = nvmet_execute_flush;
		req->data_len = 0;
		return 0;
	case nvme_cmd_dsm:
		req->execute = nvmet_execute_dsm;
		req->data_len = le32_to_cpu(cmd->dsm.nr + 1) *
			sizeof(struct nvme_dsm_range);
		return 0;
	default:
		pr_err("nvmet: unhandled cmd %d\n", cmd->common.opcode);
		return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
	}
}
Commit	Line	Data
a07b4970 CH	1	/*
	2	* NVMe I/O command implementation.
	3	* Copyright (c) 2015-2016 HGST, a Western Digital Company.
	4	*
	5	* This program is free software; you can redistribute it and/or modify it
	6	* under the terms and conditions of the GNU General Public License,
	7	* version 2, as published by the Free Software Foundation.
	8	*
	9	* This program is distributed in the hope it will be useful, but WITHOUT
	10	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	11	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	12	* more details.
	13	*/
	14	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
	15	#include <linux/blkdev.h>
	16	#include <linux/module.h>
	17	#include "nvmet.h"
	18
	19	static void nvmet_bio_done(struct bio *bio)
	20	{
	21	struct nvmet_req *req = bio->bi_private;
	22
	23	nvmet_req_complete(req,
	24	bio->bi_error ? NVME_SC_INTERNAL \| NVME_SC_DNR : 0);
	25
	26	if (bio != &req->inline_bio)
	27	bio_put(bio);
	28	}
	29
	30	static inline u32 nvmet_rw_len(struct nvmet_req *req)
	31	{
	32	return ((u32)le16_to_cpu(req->cmd->rw.length) + 1) <<
	33	req->ns->blksize_shift;
	34	}
	35
	36	static void nvmet_inline_bio_init(struct nvmet_req *req)
	37	{
	38	struct bio *bio = &req->inline_bio;
	39
	40	bio_init(bio);
	41	bio->bi_max_vecs = NVMET_MAX_INLINE_BIOVEC;
	42	bio->bi_io_vec = req->inline_bvec;
	43	}
	44
	45	static void nvmet_execute_rw(struct nvmet_req *req)
	46	{
	47	int sg_cnt = req->sg_cnt;
	48	struct scatterlist *sg;
	49	struct bio *bio;
	50	sector_t sector;
	51	blk_qc_t cookie;
	52	int op, op_flags = 0, i;
	53
	54	if (!req->sg_cnt) {
	55	nvmet_req_complete(req, 0);
	56	return;
	57	}
	58
	59	if (req->cmd->rw.opcode == nvme_cmd_write) {
	60	op = REQ_OP_WRITE;
70fd7614	61	op_flags = REQ_SYNC \| REQ_IDLE;
a07b4970 CH	62	if (req->cmd->rw.control & cpu_to_le16(NVME_RW_FUA))
	63	op_flags \|= REQ_FUA;
	64	} else {
	65	op = REQ_OP_READ;
	66	}
	67
	68	sector = le64_to_cpu(req->cmd->rw.slba);
	69	sector <<= (req->ns->blksize_shift - 9);
	70
	71	nvmet_inline_bio_init(req);
	72	bio = &req->inline_bio;
	73	bio->bi_bdev = req->ns->bdev;
	74	bio->bi_iter.bi_sector = sector;
	75	bio->bi_private = req;
	76	bio->bi_end_io = nvmet_bio_done;
	77	bio_set_op_attrs(bio, op, op_flags);
	78
	79	for_each_sg(req->sg, sg, req->sg_cnt, i) {
	80	while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
	81	!= sg->length) {
	82	struct bio *prev = bio;
	83
	84	bio = bio_alloc(GFP_KERNEL, min(sg_cnt, BIO_MAX_PAGES));
	85	bio->bi_bdev = req->ns->bdev;
	86	bio->bi_iter.bi_sector = sector;
	87	bio_set_op_attrs(bio, op, op_flags);
	88
	89	bio_chain(bio, prev);
	90	cookie = submit_bio(prev);
	91	}
	92
	93	sector += sg->length >> 9;
	94	sg_cnt--;
	95	}
	96
	97	cookie = submit_bio(bio);
	98
	99	blk_poll(bdev_get_queue(req->ns->bdev), cookie);
	100	}
	101
	102	static void nvmet_execute_flush(struct nvmet_req *req)
	103	{
	104	struct bio *bio;
	105
	106	nvmet_inline_bio_init(req);
	107	bio = &req->inline_bio;
	108
	109	bio->bi_bdev = req->ns->bdev;
	110	bio->bi_private = req;
	111	bio->bi_end_io = nvmet_bio_done;
70fd7614	112	bio->bi_opf = REQ_OP_WRITE \| REQ_PREFLUSH;
a07b4970 CH	113
	114	submit_bio(bio);
	115	}
	116
	117	static u16 nvmet_discard_range(struct nvmet_ns *ns,
	118	struct nvme_dsm_range range, struct bio *bio)
	119	{
	120	if (__blkdev_issue_discard(ns->bdev,
	121	le64_to_cpu(range->slba) << (ns->blksize_shift - 9),
	122	le32_to_cpu(range->nlb) << (ns->blksize_shift - 9),
	123	GFP_KERNEL, 0, bio))
	124	return NVME_SC_INTERNAL \| NVME_SC_DNR;
	125	return 0;
	126	}
	127
	128	static void nvmet_execute_discard(struct nvmet_req *req)
	129	{
	130	struct nvme_dsm_range range;
	131	struct bio *bio = NULL;
	132	int i;
	133	u16 status;
	134
	135	for (i = 0; i <= le32_to_cpu(req->cmd->dsm.nr); i++) {
	136	status = nvmet_copy_from_sgl(req, i * sizeof(range), &range,
	137	sizeof(range));
	138	if (status)
	139	break;
	140
	141	status = nvmet_discard_range(req->ns, &range, &bio);
	142	if (status)
	143	break;
	144	}
	145
	146	if (bio) {
	147	bio->bi_private = req;
	148	bio->bi_end_io = nvmet_bio_done;
	149	if (status) {
	150	bio->bi_error = -EIO;
	151	bio_endio(bio);
	152	} else {
	153	submit_bio(bio);
	154	}
	155	} else {
	156	nvmet_req_complete(req, status);
	157	}
	158	}
	159
	160	static void nvmet_execute_dsm(struct nvmet_req *req)
	161	{
	162	switch (le32_to_cpu(req->cmd->dsm.attributes)) {
	163	case NVME_DSMGMT_AD:
	164	nvmet_execute_discard(req);
	165	return;
	166	case NVME_DSMGMT_IDR:
	167	case NVME_DSMGMT_IDW:
	168	default:
	169	/* Not supported yet */
	170	nvmet_req_complete(req, 0);
	171	return;
	172	}
	173	}
	174
	175	int nvmet_parse_io_cmd(struct nvmet_req *req)
	176	{
177	struct nvme_command *cmd = req->cmd;
178
179	if (unlikely(!(req->sq->ctrl->cc & NVME_CC_ENABLE))) {
180	pr_err("nvmet: got io cmd %d while CC.EN == 0\n",
181	cmd->common.opcode);
182	req->ns = NULL;
183	return NVME_SC_CMD_SEQ_ERROR \| NVME_SC_DNR;
184	}
185
186	if (unlikely(!(req->sq->ctrl->csts & NVME_CSTS_RDY))) {
187	pr_err("nvmet: got io cmd %d while CSTS.RDY == 0\n",
188	cmd->common.opcode);
189	req->ns = NULL;
190	return NVME_SC_CMD_SEQ_ERROR \| NVME_SC_DNR;
191	}
192
193	req->ns = nvmet_find_namespace(req->sq->ctrl, cmd->rw.nsid);
194	if (!req->ns)
195	return NVME_SC_INVALID_NS \| NVME_SC_DNR;
196
197	switch (cmd->common.opcode) {
198	case nvme_cmd_read:
199	case nvme_cmd_write:
200	req->execute = nvmet_execute_rw;
201	req->data_len = nvmet_rw_len(req);
202	return 0;
203	case nvme_cmd_flush:
204	req->execute = nvmet_execute_flush;
205	req->data_len = 0;
206	return 0;
207	case nvme_cmd_dsm:
208	req->execute = nvmet_execute_dsm;
2e5d0baa	209	req->data_len = le32_to_cpu(cmd->dsm.nr + 1) *
a07b4970 CH	210	sizeof(struct nvme_dsm_range);
	211	return 0;
	212	default:
	213	pr_err("nvmet: unhandled cmd %d\n", cmd->common.opcode);
	214	return NVME_SC_INVALID_OPCODE \| NVME_SC_DNR;
	215	}
	216	}