1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2015 Intel Corporation
4 * Keith Busch <kbusch@kernel.org>
5 */
6#include <linux/blkdev.h>
7#include <linux/pr.h>
8#include <asm/unaligned.h>
9
10#include "nvme.h"
11
12static enum nvme_pr_type nvme_pr_type_from_blk(enum pr_type type)
13{
14 switch (type) {
15 case PR_WRITE_EXCLUSIVE:
16 return NVME_PR_WRITE_EXCLUSIVE;
17 case PR_EXCLUSIVE_ACCESS:
18 return NVME_PR_EXCLUSIVE_ACCESS;
19 case PR_WRITE_EXCLUSIVE_REG_ONLY:
20 return NVME_PR_WRITE_EXCLUSIVE_REG_ONLY;
21 case PR_EXCLUSIVE_ACCESS_REG_ONLY:
22 return NVME_PR_EXCLUSIVE_ACCESS_REG_ONLY;
23 case PR_WRITE_EXCLUSIVE_ALL_REGS:
24 return NVME_PR_WRITE_EXCLUSIVE_ALL_REGS;
25 case PR_EXCLUSIVE_ACCESS_ALL_REGS:
26 return NVME_PR_EXCLUSIVE_ACCESS_ALL_REGS;
27 }
28
29 return 0;
30}
31
32static enum pr_type block_pr_type_from_nvme(enum nvme_pr_type type)
33{
34 switch (type) {
35 case NVME_PR_WRITE_EXCLUSIVE:
36 return PR_WRITE_EXCLUSIVE;
37 case NVME_PR_EXCLUSIVE_ACCESS:
38 return PR_EXCLUSIVE_ACCESS;
39 case NVME_PR_WRITE_EXCLUSIVE_REG_ONLY:
40 return PR_WRITE_EXCLUSIVE_REG_ONLY;
41 case NVME_PR_EXCLUSIVE_ACCESS_REG_ONLY:
42 return PR_EXCLUSIVE_ACCESS_REG_ONLY;
43 case NVME_PR_WRITE_EXCLUSIVE_ALL_REGS:
44 return PR_WRITE_EXCLUSIVE_ALL_REGS;
45 case NVME_PR_EXCLUSIVE_ACCESS_ALL_REGS:
46 return PR_EXCLUSIVE_ACCESS_ALL_REGS;
47 }
48
49 return 0;
50}
51
52static int nvme_send_ns_head_pr_command(struct block_device *bdev,
53 struct nvme_command *c, void *data, unsigned int data_len)
54{
55 struct nvme_ns_head *head = bdev->bd_disk->private_data;
56 int srcu_idx = srcu_read_lock(ssp: &head->srcu);
57 struct nvme_ns *ns = nvme_find_path(head);
58 int ret = -EWOULDBLOCK;
59
60 if (ns) {
61 c->common.nsid = cpu_to_le32(ns->head->ns_id);
62 ret = nvme_submit_sync_cmd(q: ns->queue, cmd: c, buf: data, bufflen: data_len);
63 }
64 srcu_read_unlock(ssp: &head->srcu, idx: srcu_idx);
65 return ret;
66}
67
68static int nvme_send_ns_pr_command(struct nvme_ns *ns, struct nvme_command *c,
69 void *data, unsigned int data_len)
70{
71 c->common.nsid = cpu_to_le32(ns->head->ns_id);
72 return nvme_submit_sync_cmd(q: ns->queue, cmd: c, buf: data, bufflen: data_len);
73}
74
75static int nvme_sc_to_pr_err(int nvme_sc)
76{
77 if (nvme_is_path_error(status: nvme_sc))
78 return PR_STS_PATH_FAILED;
79
80 switch (nvme_sc) {
81 case NVME_SC_SUCCESS:
82 return PR_STS_SUCCESS;
83 case NVME_SC_RESERVATION_CONFLICT:
84 return PR_STS_RESERVATION_CONFLICT;
85 case NVME_SC_ONCS_NOT_SUPPORTED:
86 return -EOPNOTSUPP;
87 case NVME_SC_BAD_ATTRIBUTES:
88 case NVME_SC_INVALID_OPCODE:
89 case NVME_SC_INVALID_FIELD:
90 case NVME_SC_INVALID_NS:
91 return -EINVAL;
92 default:
93 return PR_STS_IOERR;
94 }
95}
96
97static int nvme_send_pr_command(struct block_device *bdev,
98 struct nvme_command *c, void *data, unsigned int data_len)
99{
100 if (nvme_disk_is_ns_head(disk: bdev->bd_disk))
101 return nvme_send_ns_head_pr_command(bdev, c, data, data_len);
102
103 return nvme_send_ns_pr_command(ns: bdev->bd_disk->private_data, c, data,
104 data_len);
105}
106
107static int nvme_pr_command(struct block_device *bdev, u32 cdw10,
108 u64 key, u64 sa_key, u8 op)
109{
110 struct nvme_command c = { };
111 u8 data[16] = { 0, };
112 int ret;
113
114 put_unaligned_le64(val: key, p: &data[0]);
115 put_unaligned_le64(val: sa_key, p: &data[8]);
116
117 c.common.opcode = op;
118 c.common.cdw10 = cpu_to_le32(cdw10);
119
120 ret = nvme_send_pr_command(bdev, c: &c, data, data_len: sizeof(data));
121 if (ret < 0)
122 return ret;
123
124 return nvme_sc_to_pr_err(nvme_sc: ret);
125}
126
127static int nvme_pr_register(struct block_device *bdev, u64 old,
128 u64 new, unsigned flags)
129{
130 u32 cdw10;
131
132 if (flags & ~PR_FL_IGNORE_KEY)
133 return -EOPNOTSUPP;
134
135 cdw10 = old ? 2 : 0;
136 cdw10 |= (flags & PR_FL_IGNORE_KEY) ? 1 << 3 : 0;
137 cdw10 |= (1 << 30) | (1 << 31); /* PTPL=1 */
138 return nvme_pr_command(bdev, cdw10, key: old, sa_key: new, op: nvme_cmd_resv_register);
139}
140
141static int nvme_pr_reserve(struct block_device *bdev, u64 key,
142 enum pr_type type, unsigned flags)
143{
144 u32 cdw10;
145
146 if (flags & ~PR_FL_IGNORE_KEY)
147 return -EOPNOTSUPP;
148
149 cdw10 = nvme_pr_type_from_blk(type) << 8;
150 cdw10 |= ((flags & PR_FL_IGNORE_KEY) ? 1 << 3 : 0);
151 return nvme_pr_command(bdev, cdw10, key, sa_key: 0, op: nvme_cmd_resv_acquire);
152}
153
154static int nvme_pr_preempt(struct block_device *bdev, u64 old, u64 new,
155 enum pr_type type, bool abort)
156{
157 u32 cdw10 = nvme_pr_type_from_blk(type) << 8 | (abort ? 2 : 1);
158
159 return nvme_pr_command(bdev, cdw10, key: old, sa_key: new, op: nvme_cmd_resv_acquire);
160}
161
162static int nvme_pr_clear(struct block_device *bdev, u64 key)
163{
164 u32 cdw10 = 1 | (key ? 0 : 1 << 3);
165
166 return nvme_pr_command(bdev, cdw10, key, sa_key: 0, op: nvme_cmd_resv_release);
167}
168
169static int nvme_pr_release(struct block_device *bdev, u64 key, enum pr_type type)
170{
171 u32 cdw10 = nvme_pr_type_from_blk(type) << 8 | (key ? 0 : 1 << 3);
172
173 return nvme_pr_command(bdev, cdw10, key, sa_key: 0, op: nvme_cmd_resv_release);
174}
175
176static int nvme_pr_resv_report(struct block_device *bdev, void *data,
177 u32 data_len, bool *eds)
178{
179 struct nvme_command c = { };
180 int ret;
181
182 c.common.opcode = nvme_cmd_resv_report;
183 c.common.cdw10 = cpu_to_le32(nvme_bytes_to_numd(data_len));
184 c.common.cdw11 = cpu_to_le32(NVME_EXTENDED_DATA_STRUCT);
185 *eds = true;
186
187retry:
188 ret = nvme_send_pr_command(bdev, c: &c, data, data_len);
189 if (ret == NVME_SC_HOST_ID_INCONSIST &&
190 c.common.cdw11 == cpu_to_le32(NVME_EXTENDED_DATA_STRUCT)) {
191 c.common.cdw11 = 0;
192 *eds = false;
193 goto retry;
194 }
195
196 if (ret < 0)
197 return ret;
198
199 return nvme_sc_to_pr_err(nvme_sc: ret);
200}
201
202static int nvme_pr_read_keys(struct block_device *bdev,
203 struct pr_keys *keys_info)
204{
205 u32 rse_len, num_keys = keys_info->num_keys;
206 struct nvme_reservation_status_ext *rse;
207 int ret, i;
208 bool eds;
209
210 /*
211 * Assume we are using 128-bit host IDs and allocate a buffer large
212 * enough to get enough keys to fill the return keys buffer.
213 */
214 rse_len = struct_size(rse, regctl_eds, num_keys);
215 rse = kzalloc(size: rse_len, GFP_KERNEL);
216 if (!rse)
217 return -ENOMEM;
218
219 ret = nvme_pr_resv_report(bdev, data: rse, data_len: rse_len, eds: &eds);
220 if (ret)
221 goto free_rse;
222
223 keys_info->generation = le32_to_cpu(rse->gen);
224 keys_info->num_keys = get_unaligned_le16(p: &rse->regctl);
225
226 num_keys = min(num_keys, keys_info->num_keys);
227 for (i = 0; i < num_keys; i++) {
228 if (eds) {
229 keys_info->keys[i] =
230 le64_to_cpu(rse->regctl_eds[i].rkey);
231 } else {
232 struct nvme_reservation_status *rs;
233
234 rs = (struct nvme_reservation_status *)rse;
235 keys_info->keys[i] = le64_to_cpu(rs->regctl_ds[i].rkey);
236 }
237 }
238
239free_rse:
240 kfree(objp: rse);
241 return ret;
242}
243
244static int nvme_pr_read_reservation(struct block_device *bdev,
245 struct pr_held_reservation *resv)
246{
247 struct nvme_reservation_status_ext tmp_rse, *rse;
248 int ret, i, num_regs;
249 u32 rse_len;
250 bool eds;
251
252get_num_regs:
253 /*
254 * Get the number of registrations so we know how big to allocate
255 * the response buffer.
256 */
257 ret = nvme_pr_resv_report(bdev, data: &tmp_rse, data_len: sizeof(tmp_rse), eds: &eds);
258 if (ret)
259 return ret;
260
261 num_regs = get_unaligned_le16(p: &tmp_rse.regctl);
262 if (!num_regs) {
263 resv->generation = le32_to_cpu(tmp_rse.gen);
264 return 0;
265 }
266
267 rse_len = struct_size(rse, regctl_eds, num_regs);
268 rse = kzalloc(size: rse_len, GFP_KERNEL);
269 if (!rse)
270 return -ENOMEM;
271
272 ret = nvme_pr_resv_report(bdev, data: rse, data_len: rse_len, eds: &eds);
273 if (ret)
274 goto free_rse;
275
276 if (num_regs != get_unaligned_le16(p: &rse->regctl)) {
277 kfree(objp: rse);
278 goto get_num_regs;
279 }
280
281 resv->generation = le32_to_cpu(rse->gen);
282 resv->type = block_pr_type_from_nvme(type: rse->rtype);
283
284 for (i = 0; i < num_regs; i++) {
285 if (eds) {
286 if (rse->regctl_eds[i].rcsts) {
287 resv->key = le64_to_cpu(rse->regctl_eds[i].rkey);
288 break;
289 }
290 } else {
291 struct nvme_reservation_status *rs;
292
293 rs = (struct nvme_reservation_status *)rse;
294 if (rs->regctl_ds[i].rcsts) {
295 resv->key = le64_to_cpu(rs->regctl_ds[i].rkey);
296 break;
297 }
298 }
299 }
300
301free_rse:
302 kfree(objp: rse);
303 return ret;
304}
305
306const struct pr_ops nvme_pr_ops = {
307 .pr_register = nvme_pr_register,
308 .pr_reserve = nvme_pr_reserve,
309 .pr_release = nvme_pr_release,
310 .pr_preempt = nvme_pr_preempt,
311 .pr_clear = nvme_pr_clear,
312 .pr_read_keys = nvme_pr_read_keys,
313 .pr_read_reservation = nvme_pr_read_reservation,
314};
315

source code of linux/drivers/nvme/host/pr.c