Linux-libre 4.9.46-gnu
[librecmc/linux-libre.git] / drivers / nvme / host / fabrics.c
1 /*
2  * NVMe over Fabrics common host code.
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/init.h>
16 #include <linux/miscdevice.h>
17 #include <linux/module.h>
18 #include <linux/mutex.h>
19 #include <linux/parser.h>
20 #include <linux/seq_file.h>
21 #include "nvme.h"
22 #include "fabrics.h"
23
24 static LIST_HEAD(nvmf_transports);
25 static DEFINE_MUTEX(nvmf_transports_mutex);
26
27 static LIST_HEAD(nvmf_hosts);
28 static DEFINE_MUTEX(nvmf_hosts_mutex);
29
30 static struct nvmf_host *nvmf_default_host;
31
32 static struct nvmf_host *__nvmf_host_find(const char *hostnqn)
33 {
34         struct nvmf_host *host;
35
36         list_for_each_entry(host, &nvmf_hosts, list) {
37                 if (!strcmp(host->nqn, hostnqn))
38                         return host;
39         }
40
41         return NULL;
42 }
43
44 static struct nvmf_host *nvmf_host_add(const char *hostnqn)
45 {
46         struct nvmf_host *host;
47
48         mutex_lock(&nvmf_hosts_mutex);
49         host = __nvmf_host_find(hostnqn);
50         if (host) {
51                 kref_get(&host->ref);
52                 goto out_unlock;
53         }
54
55         host = kmalloc(sizeof(*host), GFP_KERNEL);
56         if (!host)
57                 goto out_unlock;
58
59         kref_init(&host->ref);
60         memcpy(host->nqn, hostnqn, NVMF_NQN_SIZE);
61         uuid_be_gen(&host->id);
62
63         list_add_tail(&host->list, &nvmf_hosts);
64 out_unlock:
65         mutex_unlock(&nvmf_hosts_mutex);
66         return host;
67 }
68
69 static struct nvmf_host *nvmf_host_default(void)
70 {
71         struct nvmf_host *host;
72
73         host = kmalloc(sizeof(*host), GFP_KERNEL);
74         if (!host)
75                 return NULL;
76
77         kref_init(&host->ref);
78         uuid_be_gen(&host->id);
79         snprintf(host->nqn, NVMF_NQN_SIZE,
80                 "nqn.2014-08.org.nvmexpress:NVMf:uuid:%pUb", &host->id);
81
82         mutex_lock(&nvmf_hosts_mutex);
83         list_add_tail(&host->list, &nvmf_hosts);
84         mutex_unlock(&nvmf_hosts_mutex);
85
86         return host;
87 }
88
89 static void nvmf_host_destroy(struct kref *ref)
90 {
91         struct nvmf_host *host = container_of(ref, struct nvmf_host, ref);
92
93         mutex_lock(&nvmf_hosts_mutex);
94         list_del(&host->list);
95         mutex_unlock(&nvmf_hosts_mutex);
96
97         kfree(host);
98 }
99
100 static void nvmf_host_put(struct nvmf_host *host)
101 {
102         if (host)
103                 kref_put(&host->ref, nvmf_host_destroy);
104 }
105
106 /**
107  * nvmf_get_address() -  Get address/port
108  * @ctrl:       Host NVMe controller instance which we got the address
109  * @buf:        OUTPUT parameter that will contain the address/port
110  * @size:       buffer size
111  */
112 int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size)
113 {
114         int len = 0;
115
116         if (ctrl->opts->mask & NVMF_OPT_TRADDR)
117                 len += snprintf(buf, size, "traddr=%s", ctrl->opts->traddr);
118         if (ctrl->opts->mask & NVMF_OPT_TRSVCID)
119                 len += snprintf(buf + len, size - len, "%strsvcid=%s",
120                                 (len) ? "," : "", ctrl->opts->trsvcid);
121         if (ctrl->opts->mask & NVMF_OPT_HOST_TRADDR)
122                 len += snprintf(buf + len, size - len, "%shost_traddr=%s",
123                                 (len) ? "," : "", ctrl->opts->host_traddr);
124         len += snprintf(buf + len, size - len, "\n");
125
126         return len;
127 }
128 EXPORT_SYMBOL_GPL(nvmf_get_address);
129
130 /**
131  * nvmf_get_subsysnqn() - Get subsystem NQN
132  * @ctrl:       Host NVMe controller instance which we got the NQN
133  */
134 const char *nvmf_get_subsysnqn(struct nvme_ctrl *ctrl)
135 {
136         return ctrl->opts->subsysnqn;
137 }
138 EXPORT_SYMBOL_GPL(nvmf_get_subsysnqn);
139
140 /**
141  * nvmf_reg_read32() -  NVMe Fabrics "Property Get" API function.
142  * @ctrl:       Host NVMe controller instance maintaining the admin
143  *              queue used to submit the property read command to
144  *              the allocated NVMe controller resource on the target system.
145  * @off:        Starting offset value of the targeted property
146  *              register (see the fabrics section of the NVMe standard).
147  * @val:        OUTPUT parameter that will contain the value of
148  *              the property after a successful read.
149  *
150  * Used by the host system to retrieve a 32-bit capsule property value
151  * from an NVMe controller on the target system.
152  *
153  * ("Capsule property" is an "PCIe register concept" applied to the
154  * NVMe fabrics space.)
155  *
156  * Return:
157  *      0: successful read
158  *      > 0: NVMe error status code
159  *      < 0: Linux errno error code
160  */
161 int nvmf_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val)
162 {
163         struct nvme_command cmd;
164         struct nvme_completion cqe;
165         int ret;
166
167         memset(&cmd, 0, sizeof(cmd));
168         cmd.prop_get.opcode = nvme_fabrics_command;
169         cmd.prop_get.fctype = nvme_fabrics_type_property_get;
170         cmd.prop_get.offset = cpu_to_le32(off);
171
172         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, &cqe, NULL, 0, 0,
173                         NVME_QID_ANY, 0, 0);
174
175         if (ret >= 0)
176                 *val = le64_to_cpu(cqe.result64);
177         if (unlikely(ret != 0))
178                 dev_err(ctrl->device,
179                         "Property Get error: %d, offset %#x\n",
180                         ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
181
182         return ret;
183 }
184 EXPORT_SYMBOL_GPL(nvmf_reg_read32);
185
186 /**
187  * nvmf_reg_read64() -  NVMe Fabrics "Property Get" API function.
188  * @ctrl:       Host NVMe controller instance maintaining the admin
189  *              queue used to submit the property read command to
190  *              the allocated controller resource on the target system.
191  * @off:        Starting offset value of the targeted property
192  *              register (see the fabrics section of the NVMe standard).
193  * @val:        OUTPUT parameter that will contain the value of
194  *              the property after a successful read.
195  *
196  * Used by the host system to retrieve a 64-bit capsule property value
197  * from an NVMe controller on the target system.
198  *
199  * ("Capsule property" is an "PCIe register concept" applied to the
200  * NVMe fabrics space.)
201  *
202  * Return:
203  *      0: successful read
204  *      > 0: NVMe error status code
205  *      < 0: Linux errno error code
206  */
207 int nvmf_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val)
208 {
209         struct nvme_command cmd;
210         struct nvme_completion cqe;
211         int ret;
212
213         memset(&cmd, 0, sizeof(cmd));
214         cmd.prop_get.opcode = nvme_fabrics_command;
215         cmd.prop_get.fctype = nvme_fabrics_type_property_get;
216         cmd.prop_get.attrib = 1;
217         cmd.prop_get.offset = cpu_to_le32(off);
218
219         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, &cqe, NULL, 0, 0,
220                         NVME_QID_ANY, 0, 0);
221
222         if (ret >= 0)
223                 *val = le64_to_cpu(cqe.result64);
224         if (unlikely(ret != 0))
225                 dev_err(ctrl->device,
226                         "Property Get error: %d, offset %#x\n",
227                         ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
228         return ret;
229 }
230 EXPORT_SYMBOL_GPL(nvmf_reg_read64);
231
232 /**
233  * nvmf_reg_write32() -  NVMe Fabrics "Property Write" API function.
234  * @ctrl:       Host NVMe controller instance maintaining the admin
235  *              queue used to submit the property read command to
236  *              the allocated NVMe controller resource on the target system.
237  * @off:        Starting offset value of the targeted property
238  *              register (see the fabrics section of the NVMe standard).
239  * @val:        Input parameter that contains the value to be
240  *              written to the property.
241  *
242  * Used by the NVMe host system to write a 32-bit capsule property value
243  * to an NVMe controller on the target system.
244  *
245  * ("Capsule property" is an "PCIe register concept" applied to the
246  * NVMe fabrics space.)
247  *
248  * Return:
249  *      0: successful write
250  *      > 0: NVMe error status code
251  *      < 0: Linux errno error code
252  */
253 int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val)
254 {
255         struct nvme_command cmd;
256         int ret;
257
258         memset(&cmd, 0, sizeof(cmd));
259         cmd.prop_set.opcode = nvme_fabrics_command;
260         cmd.prop_set.fctype = nvme_fabrics_type_property_set;
261         cmd.prop_set.attrib = 0;
262         cmd.prop_set.offset = cpu_to_le32(off);
263         cmd.prop_set.value = cpu_to_le64(val);
264
265         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, NULL, NULL, 0, 0,
266                         NVME_QID_ANY, 0, 0);
267         if (unlikely(ret))
268                 dev_err(ctrl->device,
269                         "Property Set error: %d, offset %#x\n",
270                         ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
271         return ret;
272 }
273 EXPORT_SYMBOL_GPL(nvmf_reg_write32);
274
275 /**
276  * nvmf_log_connect_error() - Error-parsing-diagnostic print
277  * out function for connect() errors.
278  *
279  * @ctrl: the specific /dev/nvmeX device that had the error.
280  *
281  * @errval: Error code to be decoded in a more human-friendly
282  *          printout.
283  *
284  * @offset: For use with the NVMe error code NVME_SC_CONNECT_INVALID_PARAM.
285  *
286  * @cmd: This is the SQE portion of a submission capsule.
287  *
288  * @data: This is the "Data" portion of a submission capsule.
289  */
290 static void nvmf_log_connect_error(struct nvme_ctrl *ctrl,
291                 int errval, int offset, struct nvme_command *cmd,
292                 struct nvmf_connect_data *data)
293 {
294         int err_sctype = errval & (~NVME_SC_DNR);
295
296         switch (err_sctype) {
297
298         case (NVME_SC_CONNECT_INVALID_PARAM):
299                 if (offset >> 16) {
300                         char *inv_data = "Connect Invalid Data Parameter";
301
302                         switch (offset & 0xffff) {
303                         case (offsetof(struct nvmf_connect_data, cntlid)):
304                                 dev_err(ctrl->device,
305                                         "%s, cntlid: %d\n",
306                                         inv_data, data->cntlid);
307                                 break;
308                         case (offsetof(struct nvmf_connect_data, hostnqn)):
309                                 dev_err(ctrl->device,
310                                         "%s, hostnqn \"%s\"\n",
311                                         inv_data, data->hostnqn);
312                                 break;
313                         case (offsetof(struct nvmf_connect_data, subsysnqn)):
314                                 dev_err(ctrl->device,
315                                         "%s, subsysnqn \"%s\"\n",
316                                         inv_data, data->subsysnqn);
317                                 break;
318                         default:
319                                 dev_err(ctrl->device,
320                                         "%s, starting byte offset: %d\n",
321                                        inv_data, offset & 0xffff);
322                                 break;
323                         }
324                 } else {
325                         char *inv_sqe = "Connect Invalid SQE Parameter";
326
327                         switch (offset) {
328                         case (offsetof(struct nvmf_connect_command, qid)):
329                                 dev_err(ctrl->device,
330                                        "%s, qid %d\n",
331                                         inv_sqe, cmd->connect.qid);
332                                 break;
333                         default:
334                                 dev_err(ctrl->device,
335                                         "%s, starting byte offset: %d\n",
336                                         inv_sqe, offset);
337                         }
338                 }
339                 break;
340         default:
341                 dev_err(ctrl->device,
342                         "Connect command failed, error wo/DNR bit: %d\n",
343                         err_sctype);
344                 break;
345         } /* switch (err_sctype) */
346 }
347
348 /**
349  * nvmf_connect_admin_queue() - NVMe Fabrics Admin Queue "Connect"
350  *                              API function.
351  * @ctrl:       Host nvme controller instance used to request
352  *              a new NVMe controller allocation on the target
353  *              system and  establish an NVMe Admin connection to
354  *              that controller.
355  *
356  * This function enables an NVMe host device to request a new allocation of
357  * an NVMe controller resource on a target system as well establish a
358  * fabrics-protocol connection of the NVMe Admin queue between the
359  * host system device and the allocated NVMe controller on the
360  * target system via a NVMe Fabrics "Connect" command.
361  *
362  * Return:
363  *      0: success
364  *      > 0: NVMe error status code
365  *      < 0: Linux errno error code
366  *
367  */
368 int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl)
369 {
370         struct nvme_command cmd;
371         struct nvme_completion cqe;
372         struct nvmf_connect_data *data;
373         int ret;
374
375         memset(&cmd, 0, sizeof(cmd));
376         cmd.connect.opcode = nvme_fabrics_command;
377         cmd.connect.fctype = nvme_fabrics_type_connect;
378         cmd.connect.qid = 0;
379
380         /*
381          * fabrics spec sets a minimum of depth 32 for admin queue,
382          * so set the queue with this depth always until
383          * justification otherwise.
384          */
385         cmd.connect.sqsize = cpu_to_le16(NVMF_AQ_DEPTH - 1);
386
387         /*
388          * Set keep-alive timeout in seconds granularity (ms * 1000)
389          * and add a grace period for controller kato enforcement
390          */
391         cmd.connect.kato = ctrl->opts->discovery_nqn ? 0 :
392                 cpu_to_le32((ctrl->kato + NVME_KATO_GRACE) * 1000);
393
394         data = kzalloc(sizeof(*data), GFP_KERNEL);
395         if (!data)
396                 return -ENOMEM;
397
398         memcpy(&data->hostid, &ctrl->opts->host->id, sizeof(uuid_be));
399         data->cntlid = cpu_to_le16(0xffff);
400         strncpy(data->subsysnqn, ctrl->opts->subsysnqn, NVMF_NQN_SIZE);
401         strncpy(data->hostnqn, ctrl->opts->host->nqn, NVMF_NQN_SIZE);
402
403         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, &cqe,
404                         data, sizeof(*data), 0, NVME_QID_ANY, 1,
405                         BLK_MQ_REQ_RESERVED | BLK_MQ_REQ_NOWAIT);
406         if (ret) {
407                 nvmf_log_connect_error(ctrl, ret, le32_to_cpu(cqe.result),
408                                        &cmd, data);
409                 goto out_free_data;
410         }
411
412         ctrl->cntlid = le16_to_cpu(cqe.result16);
413
414 out_free_data:
415         kfree(data);
416         return ret;
417 }
418 EXPORT_SYMBOL_GPL(nvmf_connect_admin_queue);
419
420 /**
421  * nvmf_connect_io_queue() - NVMe Fabrics I/O Queue "Connect"
422  *                           API function.
423  * @ctrl:       Host nvme controller instance used to establish an
424  *              NVMe I/O queue connection to the already allocated NVMe
425  *              controller on the target system.
426  * @qid:        NVMe I/O queue number for the new I/O connection between
427  *              host and target (note qid == 0 is illegal as this is
428  *              the Admin queue, per NVMe standard).
429  *
430  * This function issues a fabrics-protocol connection
431  * of a NVMe I/O queue (via NVMe Fabrics "Connect" command)
432  * between the host system device and the allocated NVMe controller
433  * on the target system.
434  *
435  * Return:
436  *      0: success
437  *      > 0: NVMe error status code
438  *      < 0: Linux errno error code
439  */
440 int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid)
441 {
442         struct nvme_command cmd;
443         struct nvmf_connect_data *data;
444         struct nvme_completion cqe;
445         int ret;
446
447         memset(&cmd, 0, sizeof(cmd));
448         cmd.connect.opcode = nvme_fabrics_command;
449         cmd.connect.fctype = nvme_fabrics_type_connect;
450         cmd.connect.qid = cpu_to_le16(qid);
451         cmd.connect.sqsize = cpu_to_le16(ctrl->sqsize);
452
453         data = kzalloc(sizeof(*data), GFP_KERNEL);
454         if (!data)
455                 return -ENOMEM;
456
457         memcpy(&data->hostid, &ctrl->opts->host->id, sizeof(uuid_be));
458         data->cntlid = cpu_to_le16(ctrl->cntlid);
459         strncpy(data->subsysnqn, ctrl->opts->subsysnqn, NVMF_NQN_SIZE);
460         strncpy(data->hostnqn, ctrl->opts->host->nqn, NVMF_NQN_SIZE);
461
462         ret = __nvme_submit_sync_cmd(ctrl->connect_q, &cmd, &cqe,
463                         data, sizeof(*data), 0, qid, 1,
464                         BLK_MQ_REQ_RESERVED | BLK_MQ_REQ_NOWAIT);
465         if (ret) {
466                 nvmf_log_connect_error(ctrl, ret, le32_to_cpu(cqe.result),
467                                        &cmd, data);
468         }
469         kfree(data);
470         return ret;
471 }
472 EXPORT_SYMBOL_GPL(nvmf_connect_io_queue);
473
474 /**
475  * nvmf_register_transport() - NVMe Fabrics Library registration function.
476  * @ops:        Transport ops instance to be registered to the
477  *              common fabrics library.
478  *
479  * API function that registers the type of specific transport fabric
480  * being implemented to the common NVMe fabrics library. Part of
481  * the overall init sequence of starting up a fabrics driver.
482  */
483 void nvmf_register_transport(struct nvmf_transport_ops *ops)
484 {
485         mutex_lock(&nvmf_transports_mutex);
486         list_add_tail(&ops->entry, &nvmf_transports);
487         mutex_unlock(&nvmf_transports_mutex);
488 }
489 EXPORT_SYMBOL_GPL(nvmf_register_transport);
490
491 /**
492  * nvmf_unregister_transport() - NVMe Fabrics Library unregistration function.
493  * @ops:        Transport ops instance to be unregistered from the
494  *              common fabrics library.
495  *
496  * Fabrics API function that unregisters the type of specific transport
497  * fabric being implemented from the common NVMe fabrics library.
498  * Part of the overall exit sequence of unloading the implemented driver.
499  */
500 void nvmf_unregister_transport(struct nvmf_transport_ops *ops)
501 {
502         mutex_lock(&nvmf_transports_mutex);
503         list_del(&ops->entry);
504         mutex_unlock(&nvmf_transports_mutex);
505 }
506 EXPORT_SYMBOL_GPL(nvmf_unregister_transport);
507
508 static struct nvmf_transport_ops *nvmf_lookup_transport(
509                 struct nvmf_ctrl_options *opts)
510 {
511         struct nvmf_transport_ops *ops;
512
513         lockdep_assert_held(&nvmf_transports_mutex);
514
515         list_for_each_entry(ops, &nvmf_transports, entry) {
516                 if (strcmp(ops->name, opts->transport) == 0)
517                         return ops;
518         }
519
520         return NULL;
521 }
522
523 static const match_table_t opt_tokens = {
524         { NVMF_OPT_TRANSPORT,           "transport=%s"          },
525         { NVMF_OPT_TRADDR,              "traddr=%s"             },
526         { NVMF_OPT_TRSVCID,             "trsvcid=%s"            },
527         { NVMF_OPT_NQN,                 "nqn=%s"                },
528         { NVMF_OPT_QUEUE_SIZE,          "queue_size=%d"         },
529         { NVMF_OPT_NR_IO_QUEUES,        "nr_io_queues=%d"       },
530         { NVMF_OPT_RECONNECT_DELAY,     "reconnect_delay=%d"    },
531         { NVMF_OPT_KATO,                "keep_alive_tmo=%d"     },
532         { NVMF_OPT_HOSTNQN,             "hostnqn=%s"            },
533         { NVMF_OPT_HOST_TRADDR,         "host_traddr=%s"        },
534         { NVMF_OPT_ERR,                 NULL                    }
535 };
536
537 static int nvmf_parse_options(struct nvmf_ctrl_options *opts,
538                 const char *buf)
539 {
540         substring_t args[MAX_OPT_ARGS];
541         char *options, *o, *p;
542         int token, ret = 0;
543         size_t nqnlen  = 0;
544
545         /* Set defaults */
546         opts->queue_size = NVMF_DEF_QUEUE_SIZE;
547         opts->nr_io_queues = num_online_cpus();
548         opts->reconnect_delay = NVMF_DEF_RECONNECT_DELAY;
549
550         options = o = kstrdup(buf, GFP_KERNEL);
551         if (!options)
552                 return -ENOMEM;
553
554         while ((p = strsep(&o, ",\n")) != NULL) {
555                 if (!*p)
556                         continue;
557
558                 token = match_token(p, opt_tokens, args);
559                 opts->mask |= token;
560                 switch (token) {
561                 case NVMF_OPT_TRANSPORT:
562                         p = match_strdup(args);
563                         if (!p) {
564                                 ret = -ENOMEM;
565                                 goto out;
566                         }
567                         opts->transport = p;
568                         break;
569                 case NVMF_OPT_NQN:
570                         p = match_strdup(args);
571                         if (!p) {
572                                 ret = -ENOMEM;
573                                 goto out;
574                         }
575                         opts->subsysnqn = p;
576                         nqnlen = strlen(opts->subsysnqn);
577                         if (nqnlen >= NVMF_NQN_SIZE) {
578                                 pr_err("%s needs to be < %d bytes\n",
579                                 opts->subsysnqn, NVMF_NQN_SIZE);
580                                 ret = -EINVAL;
581                                 goto out;
582                         }
583                         opts->discovery_nqn =
584                                 !(strcmp(opts->subsysnqn,
585                                          NVME_DISC_SUBSYS_NAME));
586                         if (opts->discovery_nqn)
587                                 opts->nr_io_queues = 0;
588                         break;
589                 case NVMF_OPT_TRADDR:
590                         p = match_strdup(args);
591                         if (!p) {
592                                 ret = -ENOMEM;
593                                 goto out;
594                         }
595                         opts->traddr = p;
596                         break;
597                 case NVMF_OPT_TRSVCID:
598                         p = match_strdup(args);
599                         if (!p) {
600                                 ret = -ENOMEM;
601                                 goto out;
602                         }
603                         opts->trsvcid = p;
604                         break;
605                 case NVMF_OPT_QUEUE_SIZE:
606                         if (match_int(args, &token)) {
607                                 ret = -EINVAL;
608                                 goto out;
609                         }
610                         if (token < NVMF_MIN_QUEUE_SIZE ||
611                             token > NVMF_MAX_QUEUE_SIZE) {
612                                 pr_err("Invalid queue_size %d\n", token);
613                                 ret = -EINVAL;
614                                 goto out;
615                         }
616                         opts->queue_size = token;
617                         break;
618                 case NVMF_OPT_NR_IO_QUEUES:
619                         if (match_int(args, &token)) {
620                                 ret = -EINVAL;
621                                 goto out;
622                         }
623                         if (token <= 0) {
624                                 pr_err("Invalid number of IOQs %d\n", token);
625                                 ret = -EINVAL;
626                                 goto out;
627                         }
628                         opts->nr_io_queues = min_t(unsigned int,
629                                         num_online_cpus(), token);
630                         break;
631                 case NVMF_OPT_KATO:
632                         if (match_int(args, &token)) {
633                                 ret = -EINVAL;
634                                 goto out;
635                         }
636
637                         if (opts->discovery_nqn) {
638                                 pr_err("Discovery controllers cannot accept keep_alive_tmo != 0\n");
639                                 ret = -EINVAL;
640                                 goto out;
641                         }
642
643                         if (token < 0) {
644                                 pr_err("Invalid keep_alive_tmo %d\n", token);
645                                 ret = -EINVAL;
646                                 goto out;
647                         } else if (token == 0) {
648                                 /* Allowed for debug */
649                                 pr_warn("keep_alive_tmo 0 won't execute keep alives!!!\n");
650                         }
651                         opts->kato = token;
652                         break;
653                 case NVMF_OPT_HOSTNQN:
654                         if (opts->host) {
655                                 pr_err("hostnqn already user-assigned: %s\n",
656                                        opts->host->nqn);
657                                 ret = -EADDRINUSE;
658                                 goto out;
659                         }
660                         p = match_strdup(args);
661                         if (!p) {
662                                 ret = -ENOMEM;
663                                 goto out;
664                         }
665                         nqnlen = strlen(p);
666                         if (nqnlen >= NVMF_NQN_SIZE) {
667                                 pr_err("%s needs to be < %d bytes\n",
668                                         p, NVMF_NQN_SIZE);
669                                 ret = -EINVAL;
670                                 goto out;
671                         }
672                         opts->host = nvmf_host_add(p);
673                         if (!opts->host) {
674                                 ret = -ENOMEM;
675                                 goto out;
676                         }
677                         break;
678                 case NVMF_OPT_RECONNECT_DELAY:
679                         if (match_int(args, &token)) {
680                                 ret = -EINVAL;
681                                 goto out;
682                         }
683                         if (token <= 0) {
684                                 pr_err("Invalid reconnect_delay %d\n", token);
685                                 ret = -EINVAL;
686                                 goto out;
687                         }
688                         opts->reconnect_delay = token;
689                         break;
690                 case NVMF_OPT_HOST_TRADDR:
691                         p = match_strdup(args);
692                         if (!p) {
693                                 ret = -ENOMEM;
694                                 goto out;
695                         }
696                         opts->host_traddr = p;
697                         break;
698                 default:
699                         pr_warn("unknown parameter or missing value '%s' in ctrl creation request\n",
700                                 p);
701                         ret = -EINVAL;
702                         goto out;
703                 }
704         }
705
706         if (!opts->host) {
707                 kref_get(&nvmf_default_host->ref);
708                 opts->host = nvmf_default_host;
709         }
710
711 out:
712         if (!opts->discovery_nqn && !opts->kato)
713                 opts->kato = NVME_DEFAULT_KATO;
714         kfree(options);
715         return ret;
716 }
717
718 static int nvmf_check_required_opts(struct nvmf_ctrl_options *opts,
719                 unsigned int required_opts)
720 {
721         if ((opts->mask & required_opts) != required_opts) {
722                 int i;
723
724                 for (i = 0; i < ARRAY_SIZE(opt_tokens); i++) {
725                         if ((opt_tokens[i].token & required_opts) &&
726                             !(opt_tokens[i].token & opts->mask)) {
727                                 pr_warn("missing parameter '%s'\n",
728                                         opt_tokens[i].pattern);
729                         }
730                 }
731
732                 return -EINVAL;
733         }
734
735         return 0;
736 }
737
738 static int nvmf_check_allowed_opts(struct nvmf_ctrl_options *opts,
739                 unsigned int allowed_opts)
740 {
741         if (opts->mask & ~allowed_opts) {
742                 int i;
743
744                 for (i = 0; i < ARRAY_SIZE(opt_tokens); i++) {
745                         if (opt_tokens[i].token & ~allowed_opts) {
746                                 pr_warn("invalid parameter '%s'\n",
747                                         opt_tokens[i].pattern);
748                         }
749                 }
750
751                 return -EINVAL;
752         }
753
754         return 0;
755 }
756
757 void nvmf_free_options(struct nvmf_ctrl_options *opts)
758 {
759         nvmf_host_put(opts->host);
760         kfree(opts->transport);
761         kfree(opts->traddr);
762         kfree(opts->trsvcid);
763         kfree(opts->subsysnqn);
764         kfree(opts->host_traddr);
765         kfree(opts);
766 }
767 EXPORT_SYMBOL_GPL(nvmf_free_options);
768
769 #define NVMF_REQUIRED_OPTS      (NVMF_OPT_TRANSPORT | NVMF_OPT_NQN)
770 #define NVMF_ALLOWED_OPTS       (NVMF_OPT_QUEUE_SIZE | NVMF_OPT_NR_IO_QUEUES | \
771                                  NVMF_OPT_KATO | NVMF_OPT_HOSTNQN)
772
773 static struct nvme_ctrl *
774 nvmf_create_ctrl(struct device *dev, const char *buf, size_t count)
775 {
776         struct nvmf_ctrl_options *opts;
777         struct nvmf_transport_ops *ops;
778         struct nvme_ctrl *ctrl;
779         int ret;
780
781         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
782         if (!opts)
783                 return ERR_PTR(-ENOMEM);
784
785         ret = nvmf_parse_options(opts, buf);
786         if (ret)
787                 goto out_free_opts;
788
789         /*
790          * Check the generic options first as we need a valid transport for
791          * the lookup below.  Then clear the generic flags so that transport
792          * drivers don't have to care about them.
793          */
794         ret = nvmf_check_required_opts(opts, NVMF_REQUIRED_OPTS);
795         if (ret)
796                 goto out_free_opts;
797         opts->mask &= ~NVMF_REQUIRED_OPTS;
798
799         mutex_lock(&nvmf_transports_mutex);
800         ops = nvmf_lookup_transport(opts);
801         if (!ops) {
802                 pr_info("no handler found for transport %s.\n",
803                         opts->transport);
804                 ret = -EINVAL;
805                 goto out_unlock;
806         }
807
808         ret = nvmf_check_required_opts(opts, ops->required_opts);
809         if (ret)
810                 goto out_unlock;
811         ret = nvmf_check_allowed_opts(opts, NVMF_ALLOWED_OPTS |
812                                 ops->allowed_opts | ops->required_opts);
813         if (ret)
814                 goto out_unlock;
815
816         ctrl = ops->create_ctrl(dev, opts);
817         if (IS_ERR(ctrl)) {
818                 ret = PTR_ERR(ctrl);
819                 goto out_unlock;
820         }
821
822         mutex_unlock(&nvmf_transports_mutex);
823         return ctrl;
824
825 out_unlock:
826         mutex_unlock(&nvmf_transports_mutex);
827 out_free_opts:
828         nvmf_host_put(opts->host);
829         kfree(opts);
830         return ERR_PTR(ret);
831 }
832
833 static struct class *nvmf_class;
834 static struct device *nvmf_device;
835 static DEFINE_MUTEX(nvmf_dev_mutex);
836
837 static ssize_t nvmf_dev_write(struct file *file, const char __user *ubuf,
838                 size_t count, loff_t *pos)
839 {
840         struct seq_file *seq_file = file->private_data;
841         struct nvme_ctrl *ctrl;
842         const char *buf;
843         int ret = 0;
844
845         if (count > PAGE_SIZE)
846                 return -ENOMEM;
847
848         buf = memdup_user_nul(ubuf, count);
849         if (IS_ERR(buf))
850                 return PTR_ERR(buf);
851
852         mutex_lock(&nvmf_dev_mutex);
853         if (seq_file->private) {
854                 ret = -EINVAL;
855                 goto out_unlock;
856         }
857
858         ctrl = nvmf_create_ctrl(nvmf_device, buf, count);
859         if (IS_ERR(ctrl)) {
860                 ret = PTR_ERR(ctrl);
861                 goto out_unlock;
862         }
863
864         seq_file->private = ctrl;
865
866 out_unlock:
867         mutex_unlock(&nvmf_dev_mutex);
868         kfree(buf);
869         return ret ? ret : count;
870 }
871
872 static int nvmf_dev_show(struct seq_file *seq_file, void *private)
873 {
874         struct nvme_ctrl *ctrl;
875         int ret = 0;
876
877         mutex_lock(&nvmf_dev_mutex);
878         ctrl = seq_file->private;
879         if (!ctrl) {
880                 ret = -EINVAL;
881                 goto out_unlock;
882         }
883
884         seq_printf(seq_file, "instance=%d,cntlid=%d\n",
885                         ctrl->instance, ctrl->cntlid);
886
887 out_unlock:
888         mutex_unlock(&nvmf_dev_mutex);
889         return ret;
890 }
891
892 static int nvmf_dev_open(struct inode *inode, struct file *file)
893 {
894         /*
895          * The miscdevice code initializes file->private_data, but doesn't
896          * make use of it later.
897          */
898         file->private_data = NULL;
899         return single_open(file, nvmf_dev_show, NULL);
900 }
901
902 static int nvmf_dev_release(struct inode *inode, struct file *file)
903 {
904         struct seq_file *seq_file = file->private_data;
905         struct nvme_ctrl *ctrl = seq_file->private;
906
907         if (ctrl)
908                 nvme_put_ctrl(ctrl);
909         return single_release(inode, file);
910 }
911
912 static const struct file_operations nvmf_dev_fops = {
913         .owner          = THIS_MODULE,
914         .write          = nvmf_dev_write,
915         .read           = seq_read,
916         .open           = nvmf_dev_open,
917         .release        = nvmf_dev_release,
918 };
919
920 static struct miscdevice nvmf_misc = {
921         .minor          = MISC_DYNAMIC_MINOR,
922         .name           = "nvme-fabrics",
923         .fops           = &nvmf_dev_fops,
924 };
925
926 static int __init nvmf_init(void)
927 {
928         int ret;
929
930         nvmf_default_host = nvmf_host_default();
931         if (!nvmf_default_host)
932                 return -ENOMEM;
933
934         nvmf_class = class_create(THIS_MODULE, "nvme-fabrics");
935         if (IS_ERR(nvmf_class)) {
936                 pr_err("couldn't register class nvme-fabrics\n");
937                 ret = PTR_ERR(nvmf_class);
938                 goto out_free_host;
939         }
940
941         nvmf_device =
942                 device_create(nvmf_class, NULL, MKDEV(0, 0), NULL, "ctl");
943         if (IS_ERR(nvmf_device)) {
944                 pr_err("couldn't create nvme-fabris device!\n");
945                 ret = PTR_ERR(nvmf_device);
946                 goto out_destroy_class;
947         }
948
949         ret = misc_register(&nvmf_misc);
950         if (ret) {
951                 pr_err("couldn't register misc device: %d\n", ret);
952                 goto out_destroy_device;
953         }
954
955         return 0;
956
957 out_destroy_device:
958         device_destroy(nvmf_class, MKDEV(0, 0));
959 out_destroy_class:
960         class_destroy(nvmf_class);
961 out_free_host:
962         nvmf_host_put(nvmf_default_host);
963         return ret;
964 }
965
966 static void __exit nvmf_exit(void)
967 {
968         misc_deregister(&nvmf_misc);
969         device_destroy(nvmf_class, MKDEV(0, 0));
970         class_destroy(nvmf_class);
971         nvmf_host_put(nvmf_default_host);
972
973         BUILD_BUG_ON(sizeof(struct nvmf_connect_command) != 64);
974         BUILD_BUG_ON(sizeof(struct nvmf_property_get_command) != 64);
975         BUILD_BUG_ON(sizeof(struct nvmf_property_set_command) != 64);
976         BUILD_BUG_ON(sizeof(struct nvmf_connect_data) != 1024);
977 }
978
979 MODULE_LICENSE("GPL v2");
980
981 module_init(nvmf_init);
982 module_exit(nvmf_exit);