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
nvmet_bdev_ns_enable(struct nvmet_ns * ns)19 int nvmet_bdev_ns_enable(struct nvmet_ns *ns)
20 {
21 int ret;
22
23 ns->bdev = blkdev_get_by_path(ns->device_path,
24 FMODE_READ | FMODE_WRITE, NULL);
25 if (IS_ERR(ns->bdev)) {
26 ret = PTR_ERR(ns->bdev);
27 if (ret != -ENOTBLK) {
28 pr_err("failed to open block device %s: (%ld)\n",
29 ns->device_path, PTR_ERR(ns->bdev));
30 }
31 ns->bdev = NULL;
32 return ret;
33 }
34 ns->size = i_size_read(ns->bdev->bd_inode);
35 ns->blksize_shift = blksize_bits(bdev_logical_block_size(ns->bdev));
36 return 0;
37 }
38
nvmet_bdev_ns_disable(struct nvmet_ns * ns)39 void nvmet_bdev_ns_disable(struct nvmet_ns *ns)
40 {
41 if (ns->bdev) {
42 blkdev_put(ns->bdev, FMODE_WRITE | FMODE_READ);
43 ns->bdev = NULL;
44 }
45 }
46
nvmet_bio_done(struct bio * bio)47 static void nvmet_bio_done(struct bio *bio)
48 {
49 struct nvmet_req *req = bio->bi_private;
50
51 nvmet_req_complete(req,
52 bio->bi_status ? NVME_SC_INTERNAL | NVME_SC_DNR : 0);
53
54 if (bio != &req->b.inline_bio)
55 bio_put(bio);
56 }
57
nvmet_bdev_execute_rw(struct nvmet_req * req)58 static void nvmet_bdev_execute_rw(struct nvmet_req *req)
59 {
60 int sg_cnt = req->sg_cnt;
61 struct bio *bio = &req->b.inline_bio;
62 struct scatterlist *sg;
63 sector_t sector;
64 blk_qc_t cookie;
65 int op, op_flags = 0, i;
66
67 if (!req->sg_cnt) {
68 nvmet_req_complete(req, 0);
69 return;
70 }
71
72 if (req->cmd->rw.opcode == nvme_cmd_write) {
73 op = REQ_OP_WRITE;
74 op_flags = REQ_SYNC | REQ_IDLE;
75 if (req->cmd->rw.control & cpu_to_le16(NVME_RW_FUA))
76 op_flags |= REQ_FUA;
77 } else {
78 op = REQ_OP_READ;
79 }
80
81 sector = le64_to_cpu(req->cmd->rw.slba);
82 sector <<= (req->ns->blksize_shift - 9);
83
84 bio_init(bio, req->inline_bvec, ARRAY_SIZE(req->inline_bvec));
85 bio_set_dev(bio, req->ns->bdev);
86 bio->bi_iter.bi_sector = sector;
87 bio->bi_private = req;
88 bio->bi_end_io = nvmet_bio_done;
89 bio_set_op_attrs(bio, op, op_flags);
90
91 for_each_sg(req->sg, sg, req->sg_cnt, i) {
92 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
93 != sg->length) {
94 struct bio *prev = bio;
95
96 bio = bio_alloc(GFP_KERNEL, min(sg_cnt, BIO_MAX_PAGES));
97 bio_set_dev(bio, req->ns->bdev);
98 bio->bi_iter.bi_sector = sector;
99 bio_set_op_attrs(bio, op, op_flags);
100
101 bio_chain(bio, prev);
102 submit_bio(prev);
103 }
104
105 sector += sg->length >> 9;
106 sg_cnt--;
107 }
108
109 cookie = submit_bio(bio);
110
111 blk_poll(bdev_get_queue(req->ns->bdev), cookie);
112 }
113
nvmet_bdev_execute_flush(struct nvmet_req * req)114 static void nvmet_bdev_execute_flush(struct nvmet_req *req)
115 {
116 struct bio *bio = &req->b.inline_bio;
117
118 bio_init(bio, req->inline_bvec, ARRAY_SIZE(req->inline_bvec));
119 bio_set_dev(bio, req->ns->bdev);
120 bio->bi_private = req;
121 bio->bi_end_io = nvmet_bio_done;
122 bio->bi_opf = REQ_OP_WRITE | REQ_PREFLUSH;
123
124 submit_bio(bio);
125 }
126
nvmet_bdev_flush(struct nvmet_req * req)127 u16 nvmet_bdev_flush(struct nvmet_req *req)
128 {
129 if (blkdev_issue_flush(req->ns->bdev, GFP_KERNEL, NULL))
130 return NVME_SC_INTERNAL | NVME_SC_DNR;
131 return 0;
132 }
133
nvmet_bdev_discard_range(struct nvmet_ns * ns,struct nvme_dsm_range * range,struct bio ** bio)134 static u16 nvmet_bdev_discard_range(struct nvmet_ns *ns,
135 struct nvme_dsm_range *range, struct bio **bio)
136 {
137 int ret;
138
139 ret = __blkdev_issue_discard(ns->bdev,
140 le64_to_cpu(range->slba) << (ns->blksize_shift - 9),
141 le32_to_cpu(range->nlb) << (ns->blksize_shift - 9),
142 GFP_KERNEL, 0, bio);
143 if (ret && ret != -EOPNOTSUPP)
144 return NVME_SC_INTERNAL | NVME_SC_DNR;
145 return 0;
146 }
147
nvmet_bdev_execute_discard(struct nvmet_req * req)148 static void nvmet_bdev_execute_discard(struct nvmet_req *req)
149 {
150 struct nvme_dsm_range range;
151 struct bio *bio = NULL;
152 int i;
153 u16 status;
154
155 for (i = 0; i <= le32_to_cpu(req->cmd->dsm.nr); i++) {
156 status = nvmet_copy_from_sgl(req, i * sizeof(range), &range,
157 sizeof(range));
158 if (status)
159 break;
160
161 status = nvmet_bdev_discard_range(req->ns, &range, &bio);
162 if (status)
163 break;
164 }
165
166 if (bio) {
167 bio->bi_private = req;
168 bio->bi_end_io = nvmet_bio_done;
169 if (status) {
170 bio->bi_status = BLK_STS_IOERR;
171 bio_endio(bio);
172 } else {
173 submit_bio(bio);
174 }
175 } else {
176 nvmet_req_complete(req, status);
177 }
178 }
179
nvmet_bdev_execute_dsm(struct nvmet_req * req)180 static void nvmet_bdev_execute_dsm(struct nvmet_req *req)
181 {
182 switch (le32_to_cpu(req->cmd->dsm.attributes)) {
183 case NVME_DSMGMT_AD:
184 nvmet_bdev_execute_discard(req);
185 return;
186 case NVME_DSMGMT_IDR:
187 case NVME_DSMGMT_IDW:
188 default:
189 /* Not supported yet */
190 nvmet_req_complete(req, 0);
191 return;
192 }
193 }
194
nvmet_bdev_execute_write_zeroes(struct nvmet_req * req)195 static void nvmet_bdev_execute_write_zeroes(struct nvmet_req *req)
196 {
197 struct nvme_write_zeroes_cmd *write_zeroes = &req->cmd->write_zeroes;
198 struct bio *bio = NULL;
199 u16 status = NVME_SC_SUCCESS;
200 sector_t sector;
201 sector_t nr_sector;
202
203 sector = le64_to_cpu(write_zeroes->slba) <<
204 (req->ns->blksize_shift - 9);
205 nr_sector = (((sector_t)le16_to_cpu(write_zeroes->length) + 1) <<
206 (req->ns->blksize_shift - 9));
207
208 if (__blkdev_issue_zeroout(req->ns->bdev, sector, nr_sector,
209 GFP_KERNEL, &bio, 0))
210 status = NVME_SC_INTERNAL | NVME_SC_DNR;
211
212 if (bio) {
213 bio->bi_private = req;
214 bio->bi_end_io = nvmet_bio_done;
215 submit_bio(bio);
216 } else {
217 nvmet_req_complete(req, status);
218 }
219 }
220
nvmet_bdev_parse_io_cmd(struct nvmet_req * req)221 u16 nvmet_bdev_parse_io_cmd(struct nvmet_req *req)
222 {
223 struct nvme_command *cmd = req->cmd;
224
225 switch (cmd->common.opcode) {
226 case nvme_cmd_read:
227 case nvme_cmd_write:
228 req->execute = nvmet_bdev_execute_rw;
229 req->data_len = nvmet_rw_len(req);
230 return 0;
231 case nvme_cmd_flush:
232 req->execute = nvmet_bdev_execute_flush;
233 req->data_len = 0;
234 return 0;
235 case nvme_cmd_dsm:
236 req->execute = nvmet_bdev_execute_dsm;
237 req->data_len = (le32_to_cpu(cmd->dsm.nr) + 1) *
238 sizeof(struct nvme_dsm_range);
239 return 0;
240 case nvme_cmd_write_zeroes:
241 req->execute = nvmet_bdev_execute_write_zeroes;
242 return 0;
243 default:
244 pr_err("unhandled cmd %d on qid %d\n", cmd->common.opcode,
245 req->sq->qid);
246 return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
247 }
248 }
249
