xref: /linux/drivers/nvme/target/admin-cmd.c (revision 071bf69a0220253a44acb8b2a27f7a262b9a46bf)
1 /*
2  * NVMe admin 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/module.h>
16 #include <linux/random.h>
17 #include <generated/utsrelease.h>
18 #include "nvmet.h"
19 
20 u32 nvmet_get_log_page_len(struct nvme_command *cmd)
21 {
22 	u32 len = le16_to_cpu(cmd->get_log_page.numdu);
23 
24 	len <<= 16;
25 	len += le16_to_cpu(cmd->get_log_page.numdl);
26 	/* NUMD is a 0's based value */
27 	len += 1;
28 	len *= sizeof(u32);
29 
30 	return len;
31 }
32 
33 static void nvmet_execute_get_log_page(struct nvmet_req *req)
34 {
35 	size_t data_len = nvmet_get_log_page_len(req->cmd);
36 	void *buf;
37 	u16 status = 0;
38 
39 	buf = kzalloc(data_len, GFP_KERNEL);
40 	if (!buf) {
41 		status = NVME_SC_INTERNAL;
42 		goto out;
43 	}
44 
45 	switch (req->cmd->get_log_page.lid) {
46 	case 0x01:
47 		/*
48 		 * We currently never set the More bit in the status field,
49 		 * so all error log entries are invalid and can be zeroed out.
50 		 * This is called a minum viable implementation (TM) of this
51 		 * mandatory log page.
52 		 */
53 		break;
54 	case 0x02:
55 		/*
56 		 * XXX: fill out actual smart log
57 		 *
58 		 * We might have a hard time coming up with useful values for
59 		 * many of the fields, and even when we have useful data
60 		 * available (e.g. units or commands read/written) those aren't
61 		 * persistent over power loss.
62 		 */
63 		break;
64 	case 0x03:
65 		/*
66 		 * We only support a single firmware slot which always is
67 		 * active, so we can zero out the whole firmware slot log and
68 		 * still claim to fully implement this mandatory log page.
69 		 */
70 		break;
71 	default:
72 		BUG();
73 	}
74 
75 	status = nvmet_copy_to_sgl(req, 0, buf, data_len);
76 
77 	kfree(buf);
78 out:
79 	nvmet_req_complete(req, status);
80 }
81 
82 static void nvmet_execute_identify_ctrl(struct nvmet_req *req)
83 {
84 	struct nvmet_ctrl *ctrl = req->sq->ctrl;
85 	struct nvme_id_ctrl *id;
86 	u64 serial;
87 	u16 status = 0;
88 
89 	id = kzalloc(sizeof(*id), GFP_KERNEL);
90 	if (!id) {
91 		status = NVME_SC_INTERNAL;
92 		goto out;
93 	}
94 
95 	/* XXX: figure out how to assign real vendors IDs. */
96 	id->vid = 0;
97 	id->ssvid = 0;
98 
99 	/* generate a random serial number as our controllers are ephemeral: */
100 	get_random_bytes(&serial, sizeof(serial));
101 	memset(id->sn, ' ', sizeof(id->sn));
102 	snprintf(id->sn, sizeof(id->sn), "%llx", serial);
103 
104 	memset(id->mn, ' ', sizeof(id->mn));
105 	strncpy((char *)id->mn, "Linux", sizeof(id->mn));
106 
107 	memset(id->fr, ' ', sizeof(id->fr));
108 	strncpy((char *)id->fr, UTS_RELEASE, sizeof(id->fr));
109 
110 	id->rab = 6;
111 
112 	/*
113 	 * XXX: figure out how we can assign a IEEE OUI, but until then
114 	 * the safest is to leave it as zeroes.
115 	 */
116 
117 	/* we support multiple ports and multiples hosts: */
118 	id->mic = (1 << 0) | (1 << 1);
119 
120 	/* no limit on data transfer sizes for now */
121 	id->mdts = 0;
122 	id->cntlid = cpu_to_le16(ctrl->cntlid);
123 	id->ver = cpu_to_le32(ctrl->subsys->ver);
124 
125 	/* XXX: figure out what to do about RTD3R/RTD3 */
126 	id->oaes = cpu_to_le32(1 << 8);
127 	id->ctratt = cpu_to_le32(1 << 0);
128 
129 	id->oacs = 0;
130 
131 	/*
132 	 * We don't really have a practical limit on the number of abort
133 	 * comands.  But we don't do anything useful for abort either, so
134 	 * no point in allowing more abort commands than the spec requires.
135 	 */
136 	id->acl = 3;
137 
138 	id->aerl = NVMET_ASYNC_EVENTS - 1;
139 
140 	/* first slot is read-only, only one slot supported */
141 	id->frmw = (1 << 0) | (1 << 1);
142 	id->lpa = (1 << 0) | (1 << 2);
143 	id->elpe = NVMET_ERROR_LOG_SLOTS - 1;
144 	id->npss = 0;
145 
146 	/* We support keep-alive timeout in granularity of seconds */
147 	id->kas = cpu_to_le16(NVMET_KAS);
148 
149 	id->sqes = (0x6 << 4) | 0x6;
150 	id->cqes = (0x4 << 4) | 0x4;
151 
152 	/* no enforcement soft-limit for maxcmd - pick arbitrary high value */
153 	id->maxcmd = cpu_to_le16(NVMET_MAX_CMD);
154 
155 	id->nn = cpu_to_le32(ctrl->subsys->max_nsid);
156 	id->oncs = cpu_to_le16(NVME_CTRL_ONCS_DSM);
157 
158 	/* XXX: don't report vwc if the underlying device is write through */
159 	id->vwc = NVME_CTRL_VWC_PRESENT;
160 
161 	/*
162 	 * We can't support atomic writes bigger than a LBA without support
163 	 * from the backend device.
164 	 */
165 	id->awun = 0;
166 	id->awupf = 0;
167 
168 	id->sgls = cpu_to_le32(1 << 0);	/* we always support SGLs */
169 	if (ctrl->ops->has_keyed_sgls)
170 		id->sgls |= cpu_to_le32(1 << 2);
171 	if (ctrl->ops->sqe_inline_size)
172 		id->sgls |= cpu_to_le32(1 << 20);
173 
174 	strcpy(id->subnqn, ctrl->subsys->subsysnqn);
175 
176 	/* Max command capsule size is sqe + single page of in-capsule data */
177 	id->ioccsz = cpu_to_le32((sizeof(struct nvme_command) +
178 				  ctrl->ops->sqe_inline_size) / 16);
179 	/* Max response capsule size is cqe */
180 	id->iorcsz = cpu_to_le32(sizeof(struct nvme_completion) / 16);
181 
182 	id->msdbd = ctrl->ops->msdbd;
183 
184 	/*
185 	 * Meh, we don't really support any power state.  Fake up the same
186 	 * values that qemu does.
187 	 */
188 	id->psd[0].max_power = cpu_to_le16(0x9c4);
189 	id->psd[0].entry_lat = cpu_to_le32(0x10);
190 	id->psd[0].exit_lat = cpu_to_le32(0x4);
191 
192 	status = nvmet_copy_to_sgl(req, 0, id, sizeof(*id));
193 
194 	kfree(id);
195 out:
196 	nvmet_req_complete(req, status);
197 }
198 
199 static void nvmet_execute_identify_ns(struct nvmet_req *req)
200 {
201 	struct nvmet_ns *ns;
202 	struct nvme_id_ns *id;
203 	u16 status = 0;
204 
205 	ns = nvmet_find_namespace(req->sq->ctrl, req->cmd->identify.nsid);
206 	if (!ns) {
207 		status = NVME_SC_INVALID_NS | NVME_SC_DNR;
208 		goto out;
209 	}
210 
211 	id = kzalloc(sizeof(*id), GFP_KERNEL);
212 	if (!id) {
213 		status = NVME_SC_INTERNAL;
214 		goto out_put_ns;
215 	}
216 
217 	/*
218 	 * nuse = ncap = nsze isn't aways true, but we have no way to find
219 	 * that out from the underlying device.
220 	 */
221 	id->ncap = id->nuse = id->nsze =
222 		cpu_to_le64(ns->size >> ns->blksize_shift);
223 
224 	/*
225 	 * We just provide a single LBA format that matches what the
226 	 * underlying device reports.
227 	 */
228 	id->nlbaf = 0;
229 	id->flbas = 0;
230 
231 	/*
232 	 * Our namespace might always be shared.  Not just with other
233 	 * controllers, but also with any other user of the block device.
234 	 */
235 	id->nmic = (1 << 0);
236 
237 	memcpy(&id->nguid, &ns->nguid, sizeof(uuid_le));
238 
239 	id->lbaf[0].ds = ns->blksize_shift;
240 
241 	status = nvmet_copy_to_sgl(req, 0, id, sizeof(*id));
242 
243 	kfree(id);
244 out_put_ns:
245 	nvmet_put_namespace(ns);
246 out:
247 	nvmet_req_complete(req, status);
248 }
249 
250 static void nvmet_execute_identify_nslist(struct nvmet_req *req)
251 {
252 	static const int buf_size = 4096;
253 	struct nvmet_ctrl *ctrl = req->sq->ctrl;
254 	struct nvmet_ns *ns;
255 	u32 min_nsid = le32_to_cpu(req->cmd->identify.nsid);
256 	__le32 *list;
257 	u16 status = 0;
258 	int i = 0;
259 
260 	list = kzalloc(buf_size, GFP_KERNEL);
261 	if (!list) {
262 		status = NVME_SC_INTERNAL;
263 		goto out;
264 	}
265 
266 	rcu_read_lock();
267 	list_for_each_entry_rcu(ns, &ctrl->subsys->namespaces, dev_link) {
268 		if (ns->nsid <= min_nsid)
269 			continue;
270 		list[i++] = cpu_to_le32(ns->nsid);
271 		if (i == buf_size / sizeof(__le32))
272 			break;
273 	}
274 	rcu_read_unlock();
275 
276 	status = nvmet_copy_to_sgl(req, 0, list, buf_size);
277 
278 	kfree(list);
279 out:
280 	nvmet_req_complete(req, status);
281 }
282 
283 /*
284  * A "mimimum viable" abort implementation: the command is mandatory in the
285  * spec, but we are not required to do any useful work.  We couldn't really
286  * do a useful abort, so don't bother even with waiting for the command
287  * to be exectuted and return immediately telling the command to abort
288  * wasn't found.
289  */
290 static void nvmet_execute_abort(struct nvmet_req *req)
291 {
292 	nvmet_set_result(req, 1);
293 	nvmet_req_complete(req, 0);
294 }
295 
296 static void nvmet_execute_set_features(struct nvmet_req *req)
297 {
298 	struct nvmet_subsys *subsys = req->sq->ctrl->subsys;
299 	u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10[0]);
300 	u64 val;
301 	u32 val32;
302 	u16 status = 0;
303 
304 	switch (cdw10 & 0xf) {
305 	case NVME_FEAT_NUM_QUEUES:
306 		nvmet_set_result(req,
307 			(subsys->max_qid - 1) | ((subsys->max_qid - 1) << 16));
308 		break;
309 	case NVME_FEAT_KATO:
310 		val = le64_to_cpu(req->cmd->prop_set.value);
311 		val32 = val & 0xffff;
312 		req->sq->ctrl->kato = DIV_ROUND_UP(val32, 1000);
313 		nvmet_set_result(req, req->sq->ctrl->kato);
314 		break;
315 	default:
316 		status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
317 		break;
318 	}
319 
320 	nvmet_req_complete(req, status);
321 }
322 
323 static void nvmet_execute_get_features(struct nvmet_req *req)
324 {
325 	struct nvmet_subsys *subsys = req->sq->ctrl->subsys;
326 	u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10[0]);
327 	u16 status = 0;
328 
329 	switch (cdw10 & 0xf) {
330 	/*
331 	 * These features are mandatory in the spec, but we don't
332 	 * have a useful way to implement them.  We'll eventually
333 	 * need to come up with some fake values for these.
334 	 */
335 #if 0
336 	case NVME_FEAT_ARBITRATION:
337 		break;
338 	case NVME_FEAT_POWER_MGMT:
339 		break;
340 	case NVME_FEAT_TEMP_THRESH:
341 		break;
342 	case NVME_FEAT_ERR_RECOVERY:
343 		break;
344 	case NVME_FEAT_IRQ_COALESCE:
345 		break;
346 	case NVME_FEAT_IRQ_CONFIG:
347 		break;
348 	case NVME_FEAT_WRITE_ATOMIC:
349 		break;
350 	case NVME_FEAT_ASYNC_EVENT:
351 		break;
352 #endif
353 	case NVME_FEAT_VOLATILE_WC:
354 		nvmet_set_result(req, 1);
355 		break;
356 	case NVME_FEAT_NUM_QUEUES:
357 		nvmet_set_result(req,
358 			(subsys->max_qid-1) | ((subsys->max_qid-1) << 16));
359 		break;
360 	case NVME_FEAT_KATO:
361 		nvmet_set_result(req, req->sq->ctrl->kato * 1000);
362 		break;
363 	default:
364 		status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
365 		break;
366 	}
367 
368 	nvmet_req_complete(req, status);
369 }
370 
371 static void nvmet_execute_async_event(struct nvmet_req *req)
372 {
373 	struct nvmet_ctrl *ctrl = req->sq->ctrl;
374 
375 	mutex_lock(&ctrl->lock);
376 	if (ctrl->nr_async_event_cmds >= NVMET_ASYNC_EVENTS) {
377 		mutex_unlock(&ctrl->lock);
378 		nvmet_req_complete(req, NVME_SC_ASYNC_LIMIT | NVME_SC_DNR);
379 		return;
380 	}
381 	ctrl->async_event_cmds[ctrl->nr_async_event_cmds++] = req;
382 	mutex_unlock(&ctrl->lock);
383 
384 	schedule_work(&ctrl->async_event_work);
385 }
386 
387 static void nvmet_execute_keep_alive(struct nvmet_req *req)
388 {
389 	struct nvmet_ctrl *ctrl = req->sq->ctrl;
390 
391 	pr_debug("ctrl %d update keep-alive timer for %d secs\n",
392 		ctrl->cntlid, ctrl->kato);
393 
394 	mod_delayed_work(system_wq, &ctrl->ka_work, ctrl->kato * HZ);
395 	nvmet_req_complete(req, 0);
396 }
397 
398 int nvmet_parse_admin_cmd(struct nvmet_req *req)
399 {
400 	struct nvme_command *cmd = req->cmd;
401 
402 	req->ns = NULL;
403 
404 	if (unlikely(!(req->sq->ctrl->cc & NVME_CC_ENABLE))) {
405 		pr_err("nvmet: got admin cmd %d while CC.EN == 0\n",
406 				cmd->common.opcode);
407 		return NVME_SC_CMD_SEQ_ERROR | NVME_SC_DNR;
408 	}
409 	if (unlikely(!(req->sq->ctrl->csts & NVME_CSTS_RDY))) {
410 		pr_err("nvmet: got admin cmd %d while CSTS.RDY == 0\n",
411 				cmd->common.opcode);
412 		return NVME_SC_CMD_SEQ_ERROR | NVME_SC_DNR;
413 	}
414 
415 	switch (cmd->common.opcode) {
416 	case nvme_admin_get_log_page:
417 		req->data_len = nvmet_get_log_page_len(cmd);
418 
419 		switch (cmd->get_log_page.lid) {
420 		case 0x01:
421 		case 0x02:
422 		case 0x03:
423 			req->execute = nvmet_execute_get_log_page;
424 			return 0;
425 		}
426 		break;
427 	case nvme_admin_identify:
428 		req->data_len = 4096;
429 		switch (le32_to_cpu(cmd->identify.cns)) {
430 		case 0x00:
431 			req->execute = nvmet_execute_identify_ns;
432 			return 0;
433 		case 0x01:
434 			req->execute = nvmet_execute_identify_ctrl;
435 			return 0;
436 		case 0x02:
437 			req->execute = nvmet_execute_identify_nslist;
438 			return 0;
439 		}
440 		break;
441 	case nvme_admin_abort_cmd:
442 		req->execute = nvmet_execute_abort;
443 		req->data_len = 0;
444 		return 0;
445 	case nvme_admin_set_features:
446 		req->execute = nvmet_execute_set_features;
447 		req->data_len = 0;
448 		return 0;
449 	case nvme_admin_get_features:
450 		req->execute = nvmet_execute_get_features;
451 		req->data_len = 0;
452 		return 0;
453 	case nvme_admin_async_event:
454 		req->execute = nvmet_execute_async_event;
455 		req->data_len = 0;
456 		return 0;
457 	case nvme_admin_keep_alive:
458 		req->execute = nvmet_execute_keep_alive;
459 		req->data_len = 0;
460 		return 0;
461 	}
462 
463 	pr_err("nvmet: unhandled cmd %d\n", cmd->common.opcode);
464 	return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
465 }
466