summaryrefslogtreecommitdiffstats
path: root/drivers/nvme/target/discovery.c
blob: 4845d12e374acd795fb4da2bf6f5fd66856260aa (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
// SPDX-License-Identifier: GPL-2.0
/*
 * Discovery service for the NVMe over Fabrics target.
 * Copyright (C) 2016 Intel Corporation. All rights reserved.
 */
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/slab.h>
#include <generated/utsrelease.h>
#include "nvmet.h"

struct nvmet_subsys *nvmet_disc_subsys;

static u64 nvmet_genctr;

static void __nvmet_disc_changed(struct nvmet_port *port,
				 struct nvmet_ctrl *ctrl)
{
	if (ctrl->port != port)
		return;

	if (nvmet_aen_bit_disabled(ctrl, NVME_AEN_BIT_DISC_CHANGE))
		return;

	nvmet_add_async_event(ctrl, NVME_AER_TYPE_NOTICE,
			      NVME_AER_NOTICE_DISC_CHANGED, NVME_LOG_DISC);
}

void nvmet_port_disc_changed(struct nvmet_port *port,
			     struct nvmet_subsys *subsys)
{
	struct nvmet_ctrl *ctrl;

	lockdep_assert_held(&nvmet_config_sem);
	nvmet_genctr++;

	mutex_lock(&nvmet_disc_subsys->lock);
	list_for_each_entry(ctrl, &nvmet_disc_subsys->ctrls, subsys_entry) {
		if (subsys && !nvmet_host_allowed(subsys, ctrl->hostnqn))
			continue;

		__nvmet_disc_changed(port, ctrl);
	}
	mutex_unlock(&nvmet_disc_subsys->lock);

	/* If transport can signal change, notify transport */
	if (port->tr_ops && port->tr_ops->discovery_chg)
		port->tr_ops->discovery_chg(port);
}

static void __nvmet_subsys_disc_changed(struct nvmet_port *port,
					struct nvmet_subsys *subsys,
					struct nvmet_host *host)
{
	struct nvmet_ctrl *ctrl;

	mutex_lock(&nvmet_disc_subsys->lock);
	list_for_each_entry(ctrl, &nvmet_disc_subsys->ctrls, subsys_entry) {
		if (host && strcmp(nvmet_host_name(host), ctrl->hostnqn))
			continue;

		__nvmet_disc_changed(port, ctrl);
	}
	mutex_unlock(&nvmet_disc_subsys->lock);
}

void nvmet_subsys_disc_changed(struct nvmet_subsys *subsys,
			       struct nvmet_host *host)
{
	struct nvmet_port *port;
	struct nvmet_subsys_link *s;

	lockdep_assert_held(&nvmet_config_sem);
	nvmet_genctr++;

	list_for_each_entry(port, nvmet_ports, global_entry)
		list_for_each_entry(s, &port->subsystems, entry) {
			if (s->subsys != subsys)
				continue;
			__nvmet_subsys_disc_changed(port, subsys, host);
		}
}

void nvmet_referral_enable(struct nvmet_port *parent, struct nvmet_port *port)
{
	down_write(&nvmet_config_sem);
	if (list_empty(&port->entry)) {
		list_add_tail(&port->entry, &parent->referrals);
		port->enabled = true;
		nvmet_port_disc_changed(parent, NULL);
	}
	up_write(&nvmet_config_sem);
}

void nvmet_referral_disable(struct nvmet_port *parent, struct nvmet_port *port)
{
	down_write(&nvmet_config_sem);
	if (!list_empty(&port->entry)) {
		port->enabled = false;
		list_del_init(&port->entry);
		nvmet_port_disc_changed(parent, NULL);
	}
	up_write(&nvmet_config_sem);
}

static void nvmet_format_discovery_entry(struct nvmf_disc_rsp_page_hdr *hdr,
		struct nvmet_port *port, char *subsys_nqn, char *traddr,
		u8 type, u32 numrec)
{
	struct nvmf_disc_rsp_page_entry *e = &hdr->entries[numrec];

	e->trtype = port->disc_addr.trtype;
	e->adrfam = port->disc_addr.adrfam;
	e->treq = port->disc_addr.treq;
	e->portid = port->disc_addr.portid;
	/* we support only dynamic controllers */
	e->cntlid = cpu_to_le16(NVME_CNTLID_DYNAMIC);
	e->asqsz = cpu_to_le16(NVME_AQ_DEPTH);
	e->subtype = type;
	memcpy(e->trsvcid, port->disc_addr.trsvcid, NVMF_TRSVCID_SIZE);
	memcpy(e->traddr, traddr, NVMF_TRADDR_SIZE);
	memcpy(e->tsas.common, port->disc_addr.tsas.common, NVMF_TSAS_SIZE);
	strncpy(e->subnqn, subsys_nqn, NVMF_NQN_SIZE);
}

/*
 * nvmet_set_disc_traddr - set a correct discovery log entry traddr
 *
 * IP based transports (e.g RDMA) can listen on "any" ipv4/ipv6 addresses
 * (INADDR_ANY or IN6ADDR_ANY_INIT). The discovery log page traddr reply
 * must not contain that "any" IP address. If the transport implements
 * .disc_traddr, use it. this callback will set the discovery traddr
 * from the req->port address in case the port in question listens
 * "any" IP address.
 */
static void nvmet_set_disc_traddr(struct nvmet_req *req, struct nvmet_port *port,
		char *traddr)
{
	if (req->ops->disc_traddr)
		req->ops->disc_traddr(req, port, traddr);
	else
		memcpy(traddr, port->disc_addr.traddr, NVMF_TRADDR_SIZE);
}

static size_t discovery_log_entries(struct nvmet_req *req)
{
	struct nvmet_ctrl *ctrl = req->sq->ctrl;
	struct nvmet_subsys_link *p;
	struct nvmet_port *r;
	size_t entries = 0;

	list_for_each_entry(p, &req->port->subsystems, entry) {
		if (!nvmet_host_allowed(p->subsys, ctrl->hostnqn))
			continue;
		entries++;
	}
	list_for_each_entry(r, &req->port->referrals, entry)
		entries++;
	return entries;
}

static void nvmet_execute_disc_get_log_page(struct nvmet_req *req)
{
	const int entry_size = sizeof(struct nvmf_disc_rsp_page_entry);
	struct nvmet_ctrl *ctrl = req->sq->ctrl;
	struct nvmf_disc_rsp_page_hdr *hdr;
	u64 offset = nvmet_get_log_page_offset(req->cmd);
	size_t data_len = nvmet_get_log_page_len(req->cmd);
	size_t alloc_len;
	struct nvmet_subsys_link *p;
	struct nvmet_port *r;
	u32 numrec = 0;
	u16 status = 0;
	void *buffer;

	if (!nvmet_check_transfer_len(req, data_len))
		return;

	if (req->cmd->get_log_page.lid != NVME_LOG_DISC) {
		req->error_loc =
			offsetof(struct nvme_get_log_page_command, lid);
		status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
		goto out;
	}

	/* Spec requires dword aligned offsets */
	if (offset & 0x3) {
		req->error_loc =
			offsetof(struct nvme_get_log_page_command, lpo);
		status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
		goto out;
	}

	/*
	 * Make sure we're passing at least a buffer of response header size.
	 * If host provided data len is less than the header size, only the
	 * number of bytes requested by host will be sent to host.
	 */
	down_read(&nvmet_config_sem);
	alloc_len = sizeof(*hdr) + entry_size * discovery_log_entries(req);
	buffer = kzalloc(alloc_len, GFP_KERNEL);
	if (!buffer) {
		up_read(&nvmet_config_sem);
		status = NVME_SC_INTERNAL;
		goto out;
	}

	hdr = buffer;
	list_for_each_entry(p, &req->port->subsystems, entry) {
		char traddr[NVMF_TRADDR_SIZE];

		if (!nvmet_host_allowed(p->subsys, ctrl->hostnqn))
			continue;

		nvmet_set_disc_traddr(req, req->port, traddr);
		nvmet_format_discovery_entry(hdr, req->port,
				p->subsys->subsysnqn, traddr,
				NVME_NQN_NVME, numrec);
		numrec++;
	}

	list_for_each_entry(r, &req->port->referrals, entry) {
		nvmet_format_discovery_entry(hdr, r,
				NVME_DISC_SUBSYS_NAME,
				r->disc_addr.traddr,
				NVME_NQN_DISC, numrec);
		numrec++;
	}

	hdr->genctr = cpu_to_le64(nvmet_genctr);
	hdr->numrec = cpu_to_le64(numrec);
	hdr->recfmt = cpu_to_le16(0);

	nvmet_clear_aen_bit(req, NVME_AEN_BIT_DISC_CHANGE);

	up_read(&nvmet_config_sem);

	status = nvmet_copy_to_sgl(req, 0, buffer + offset, data_len);
	kfree(buffer);
out:
	nvmet_req_complete(req, status);
}

static void nvmet_execute_disc_identify(struct nvmet_req *req)
{
	struct nvmet_ctrl *ctrl = req->sq->ctrl;
	struct nvme_id_ctrl *id;
	const char model[] = "Linux";
	u16 status = 0;

	if (!nvmet_check_transfer_len(req, NVME_IDENTIFY_DATA_SIZE))
		return;

	if (req->cmd->identify.cns != NVME_ID_CNS_CTRL) {
		req->error_loc = offsetof(struct nvme_identify, cns);
		status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
		goto out;
	}

	id = kzalloc(sizeof(*id), GFP_KERNEL);
	if (!id) {
		status = NVME_SC_INTERNAL;
		goto out;
	}

	memset(id->sn, ' ', sizeof(id->sn));
	bin2hex(id->sn, &ctrl->subsys->serial,
		min(sizeof(ctrl->subsys->serial), sizeof(id->sn) / 2));
	memset(id->fr, ' ', sizeof(id->fr));
	memcpy_and_pad(id->mn, sizeof(id->mn), model, sizeof(model) - 1, ' ');
	memcpy_and_pad(id->fr, sizeof(id->fr),
		       UTS_RELEASE, strlen(UTS_RELEASE), ' ');

	/* no limit on data transfer sizes for now */
	id->mdts = 0;
	id->cntlid = cpu_to_le16(ctrl->cntlid);
	id->ver = cpu_to_le32(ctrl->subsys->ver);
	id->lpa = (1 << 2);

	/* no enforcement soft-limit for maxcmd - pick arbitrary high value */
	id->maxcmd = cpu_to_le16(NVMET_MAX_CMD);

	id->sgls = cpu_to_le32(1 << 0);	/* we always support SGLs */
	if (ctrl->ops->flags & NVMF_KEYED_SGLS)
		id->sgls |= cpu_to_le32(1 << 2);
	if (req->port->inline_data_size)
		id->sgls |= cpu_to_le32(1 << 20);

	id->oaes = cpu_to_le32(NVMET_DISC_AEN_CFG_OPTIONAL);

	strlcpy(id->subnqn, ctrl->subsys->subsysnqn, sizeof(id->subnqn));

	status = nvmet_copy_to_sgl(req, 0, id, sizeof(*id));

	kfree(id);
out:
	nvmet_req_complete(req, status);
}

static void nvmet_execute_disc_set_features(struct nvmet_req *req)
{
	u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10);
	u16 stat;

	if (!nvmet_check_transfer_len(req, 0))
		return;

	switch (cdw10 & 0xff) {
	case NVME_FEAT_KATO:
		stat = nvmet_set_feat_kato(req);
		break;
	case NVME_FEAT_ASYNC_EVENT:
		stat = nvmet_set_feat_async_event(req,
						  NVMET_DISC_AEN_CFG_OPTIONAL);
		break;
	default:
		req->error_loc =
			offsetof(struct nvme_common_command, cdw10);
		stat = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
		break;
	}

	nvmet_req_complete(req, stat);
}

static void nvmet_execute_disc_get_features(struct nvmet_req *req)
{
	u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10);
	u16 stat = 0;

	if (!nvmet_check_transfer_len(req, 0))
		return;

	switch (cdw10 & 0xff) {
	case NVME_FEAT_KATO:
		nvmet_get_feat_kato(req);
		break;
	case NVME_FEAT_ASYNC_EVENT:
		nvmet_get_feat_async_event(req);
		break;
	default:
		req->error_loc =
			offsetof(struct nvme_common_command, cdw10);
		stat = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
		break;
	}

	nvmet_req_complete(req, stat);
}

u16 nvmet_parse_discovery_cmd(struct nvmet_req *req)
{
	struct nvme_command *cmd = req->cmd;

	if (unlikely(!(req->sq->ctrl->csts & NVME_CSTS_RDY))) {
		pr_err("got cmd %d while not ready\n",
		       cmd->common.opcode);
		req->error_loc =
			offsetof(struct nvme_common_command, opcode);
		return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
	}

	switch (cmd->common.opcode) {
	case nvme_admin_set_features:
		req->execute = nvmet_execute_disc_set_features;
		return 0;
	case nvme_admin_get_features:
		req->execute = nvmet_execute_disc_get_features;
		return 0;
	case nvme_admin_async_event:
		req->execute = nvmet_execute_async_event;
		return 0;
	case nvme_admin_keep_alive:
		req->execute = nvmet_execute_keep_alive;
		return 0;
	case nvme_admin_get_log_page:
		req->execute = nvmet_execute_disc_get_log_page;
		return 0;
	case nvme_admin_identify:
		req->execute = nvmet_execute_disc_identify;
		return 0;
	default:
		pr_err("unhandled cmd %d\n", cmd->common.opcode);
		req->error_loc = offsetof(struct nvme_common_command, opcode);
		return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
	}

}

int __init nvmet_init_discovery(void)
{
	nvmet_disc_subsys =
		nvmet_subsys_alloc(NVME_DISC_SUBSYS_NAME, NVME_NQN_DISC);
	return PTR_ERR_OR_ZERO(nvmet_disc_subsys);
}

void nvmet_exit_discovery(void)
{
	nvmet_subsys_put(nvmet_disc_subsys);
}