Merge tag 'for-4.19/block-20180812' of git://git.kernel.dk/linux-block
[linux-2.6-microblaze.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 DECLARE_RWSEM(nvmf_transports_rwsem);
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         strlcpy(host->nqn, hostnqn, NVMF_NQN_SIZE);
61
62         list_add_tail(&host->list, &nvmf_hosts);
63 out_unlock:
64         mutex_unlock(&nvmf_hosts_mutex);
65         return host;
66 }
67
68 static struct nvmf_host *nvmf_host_default(void)
69 {
70         struct nvmf_host *host;
71
72         host = kmalloc(sizeof(*host), GFP_KERNEL);
73         if (!host)
74                 return NULL;
75
76         kref_init(&host->ref);
77         uuid_gen(&host->id);
78         snprintf(host->nqn, NVMF_NQN_SIZE,
79                 "nqn.2014-08.org.nvmexpress:uuid:%pUb", &host->id);
80
81         mutex_lock(&nvmf_hosts_mutex);
82         list_add_tail(&host->list, &nvmf_hosts);
83         mutex_unlock(&nvmf_hosts_mutex);
84
85         return host;
86 }
87
88 static void nvmf_host_destroy(struct kref *ref)
89 {
90         struct nvmf_host *host = container_of(ref, struct nvmf_host, ref);
91
92         mutex_lock(&nvmf_hosts_mutex);
93         list_del(&host->list);
94         mutex_unlock(&nvmf_hosts_mutex);
95
96         kfree(host);
97 }
98
99 static void nvmf_host_put(struct nvmf_host *host)
100 {
101         if (host)
102                 kref_put(&host->ref, nvmf_host_destroy);
103 }
104
105 /**
106  * nvmf_get_address() -  Get address/port
107  * @ctrl:       Host NVMe controller instance which we got the address
108  * @buf:        OUTPUT parameter that will contain the address/port
109  * @size:       buffer size
110  */
111 int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size)
112 {
113         int len = 0;
114
115         if (ctrl->opts->mask & NVMF_OPT_TRADDR)
116                 len += snprintf(buf, size, "traddr=%s", ctrl->opts->traddr);
117         if (ctrl->opts->mask & NVMF_OPT_TRSVCID)
118                 len += snprintf(buf + len, size - len, "%strsvcid=%s",
119                                 (len) ? "," : "", ctrl->opts->trsvcid);
120         if (ctrl->opts->mask & NVMF_OPT_HOST_TRADDR)
121                 len += snprintf(buf + len, size - len, "%shost_traddr=%s",
122                                 (len) ? "," : "", ctrl->opts->host_traddr);
123         len += snprintf(buf + len, size - len, "\n");
124
125         return len;
126 }
127 EXPORT_SYMBOL_GPL(nvmf_get_address);
128
129 /**
130  * nvmf_reg_read32() -  NVMe Fabrics "Property Get" API function.
131  * @ctrl:       Host NVMe controller instance maintaining the admin
132  *              queue used to submit the property read command to
133  *              the allocated NVMe controller resource on the target system.
134  * @off:        Starting offset value of the targeted property
135  *              register (see the fabrics section of the NVMe standard).
136  * @val:        OUTPUT parameter that will contain the value of
137  *              the property after a successful read.
138  *
139  * Used by the host system to retrieve a 32-bit capsule property value
140  * from an NVMe controller on the target system.
141  *
142  * ("Capsule property" is an "PCIe register concept" applied to the
143  * NVMe fabrics space.)
144  *
145  * Return:
146  *      0: successful read
147  *      > 0: NVMe error status code
148  *      < 0: Linux errno error code
149  */
150 int nvmf_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val)
151 {
152         struct nvme_command cmd;
153         union nvme_result res;
154         int ret;
155
156         memset(&cmd, 0, sizeof(cmd));
157         cmd.prop_get.opcode = nvme_fabrics_command;
158         cmd.prop_get.fctype = nvme_fabrics_type_property_get;
159         cmd.prop_get.offset = cpu_to_le32(off);
160
161         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, &res, NULL, 0, 0,
162                         NVME_QID_ANY, 0, 0);
163
164         if (ret >= 0)
165                 *val = le64_to_cpu(res.u64);
166         if (unlikely(ret != 0))
167                 dev_err(ctrl->device,
168                         "Property Get error: %d, offset %#x\n",
169                         ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
170
171         return ret;
172 }
173 EXPORT_SYMBOL_GPL(nvmf_reg_read32);
174
175 /**
176  * nvmf_reg_read64() -  NVMe Fabrics "Property Get" API function.
177  * @ctrl:       Host NVMe controller instance maintaining the admin
178  *              queue used to submit the property read command to
179  *              the allocated controller resource on the target system.
180  * @off:        Starting offset value of the targeted property
181  *              register (see the fabrics section of the NVMe standard).
182  * @val:        OUTPUT parameter that will contain the value of
183  *              the property after a successful read.
184  *
185  * Used by the host system to retrieve a 64-bit capsule property value
186  * from an NVMe controller on the target system.
187  *
188  * ("Capsule property" is an "PCIe register concept" applied to the
189  * NVMe fabrics space.)
190  *
191  * Return:
192  *      0: successful read
193  *      > 0: NVMe error status code
194  *      < 0: Linux errno error code
195  */
196 int nvmf_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val)
197 {
198         struct nvme_command cmd;
199         union nvme_result res;
200         int ret;
201
202         memset(&cmd, 0, sizeof(cmd));
203         cmd.prop_get.opcode = nvme_fabrics_command;
204         cmd.prop_get.fctype = nvme_fabrics_type_property_get;
205         cmd.prop_get.attrib = 1;
206         cmd.prop_get.offset = cpu_to_le32(off);
207
208         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, &res, NULL, 0, 0,
209                         NVME_QID_ANY, 0, 0);
210
211         if (ret >= 0)
212                 *val = le64_to_cpu(res.u64);
213         if (unlikely(ret != 0))
214                 dev_err(ctrl->device,
215                         "Property Get error: %d, offset %#x\n",
216                         ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
217         return ret;
218 }
219 EXPORT_SYMBOL_GPL(nvmf_reg_read64);
220
221 /**
222  * nvmf_reg_write32() -  NVMe Fabrics "Property Write" API function.
223  * @ctrl:       Host NVMe controller instance maintaining the admin
224  *              queue used to submit the property read command to
225  *              the allocated NVMe controller resource on the target system.
226  * @off:        Starting offset value of the targeted property
227  *              register (see the fabrics section of the NVMe standard).
228  * @val:        Input parameter that contains the value to be
229  *              written to the property.
230  *
231  * Used by the NVMe host system to write a 32-bit capsule property value
232  * to an NVMe controller on the target system.
233  *
234  * ("Capsule property" is an "PCIe register concept" applied to the
235  * NVMe fabrics space.)
236  *
237  * Return:
238  *      0: successful write
239  *      > 0: NVMe error status code
240  *      < 0: Linux errno error code
241  */
242 int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val)
243 {
244         struct nvme_command cmd;
245         int ret;
246
247         memset(&cmd, 0, sizeof(cmd));
248         cmd.prop_set.opcode = nvme_fabrics_command;
249         cmd.prop_set.fctype = nvme_fabrics_type_property_set;
250         cmd.prop_set.attrib = 0;
251         cmd.prop_set.offset = cpu_to_le32(off);
252         cmd.prop_set.value = cpu_to_le64(val);
253
254         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, NULL, NULL, 0, 0,
255                         NVME_QID_ANY, 0, 0);
256         if (unlikely(ret))
257                 dev_err(ctrl->device,
258                         "Property Set error: %d, offset %#x\n",
259                         ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
260         return ret;
261 }
262 EXPORT_SYMBOL_GPL(nvmf_reg_write32);
263
264 /**
265  * nvmf_log_connect_error() - Error-parsing-diagnostic print
266  * out function for connect() errors.
267  *
268  * @ctrl: the specific /dev/nvmeX device that had the error.
269  *
270  * @errval: Error code to be decoded in a more human-friendly
271  *          printout.
272  *
273  * @offset: For use with the NVMe error code NVME_SC_CONNECT_INVALID_PARAM.
274  *
275  * @cmd: This is the SQE portion of a submission capsule.
276  *
277  * @data: This is the "Data" portion of a submission capsule.
278  */
279 static void nvmf_log_connect_error(struct nvme_ctrl *ctrl,
280                 int errval, int offset, struct nvme_command *cmd,
281                 struct nvmf_connect_data *data)
282 {
283         int err_sctype = errval & (~NVME_SC_DNR);
284
285         switch (err_sctype) {
286
287         case (NVME_SC_CONNECT_INVALID_PARAM):
288                 if (offset >> 16) {
289                         char *inv_data = "Connect Invalid Data Parameter";
290
291                         switch (offset & 0xffff) {
292                         case (offsetof(struct nvmf_connect_data, cntlid)):
293                                 dev_err(ctrl->device,
294                                         "%s, cntlid: %d\n",
295                                         inv_data, data->cntlid);
296                                 break;
297                         case (offsetof(struct nvmf_connect_data, hostnqn)):
298                                 dev_err(ctrl->device,
299                                         "%s, hostnqn \"%s\"\n",
300                                         inv_data, data->hostnqn);
301                                 break;
302                         case (offsetof(struct nvmf_connect_data, subsysnqn)):
303                                 dev_err(ctrl->device,
304                                         "%s, subsysnqn \"%s\"\n",
305                                         inv_data, data->subsysnqn);
306                                 break;
307                         default:
308                                 dev_err(ctrl->device,
309                                         "%s, starting byte offset: %d\n",
310                                        inv_data, offset & 0xffff);
311                                 break;
312                         }
313                 } else {
314                         char *inv_sqe = "Connect Invalid SQE Parameter";
315
316                         switch (offset) {
317                         case (offsetof(struct nvmf_connect_command, qid)):
318                                 dev_err(ctrl->device,
319                                        "%s, qid %d\n",
320                                         inv_sqe, cmd->connect.qid);
321                                 break;
322                         default:
323                                 dev_err(ctrl->device,
324                                         "%s, starting byte offset: %d\n",
325                                         inv_sqe, offset);
326                         }
327                 }
328                 break;
329
330         case NVME_SC_CONNECT_INVALID_HOST:
331                 dev_err(ctrl->device,
332                         "Connect for subsystem %s is not allowed, hostnqn: %s\n",
333                         data->subsysnqn, data->hostnqn);
334                 break;
335
336         case NVME_SC_CONNECT_CTRL_BUSY:
337                 dev_err(ctrl->device,
338                         "Connect command failed: controller is busy or not available\n");
339                 break;
340
341         case NVME_SC_CONNECT_FORMAT:
342                 dev_err(ctrl->device,
343                         "Connect incompatible format: %d",
344                         cmd->connect.recfmt);
345                 break;
346
347         default:
348                 dev_err(ctrl->device,
349                         "Connect command failed, error wo/DNR bit: %d\n",
350                         err_sctype);
351                 break;
352         } /* switch (err_sctype) */
353 }
354
355 /**
356  * nvmf_connect_admin_queue() - NVMe Fabrics Admin Queue "Connect"
357  *                              API function.
358  * @ctrl:       Host nvme controller instance used to request
359  *              a new NVMe controller allocation on the target
360  *              system and  establish an NVMe Admin connection to
361  *              that controller.
362  *
363  * This function enables an NVMe host device to request a new allocation of
364  * an NVMe controller resource on a target system as well establish a
365  * fabrics-protocol connection of the NVMe Admin queue between the
366  * host system device and the allocated NVMe controller on the
367  * target system via a NVMe Fabrics "Connect" command.
368  *
369  * Return:
370  *      0: success
371  *      > 0: NVMe error status code
372  *      < 0: Linux errno error code
373  *
374  */
375 int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl)
376 {
377         struct nvme_command cmd;
378         union nvme_result res;
379         struct nvmf_connect_data *data;
380         int ret;
381
382         memset(&cmd, 0, sizeof(cmd));
383         cmd.connect.opcode = nvme_fabrics_command;
384         cmd.connect.fctype = nvme_fabrics_type_connect;
385         cmd.connect.qid = 0;
386         cmd.connect.sqsize = cpu_to_le16(NVME_AQ_DEPTH - 1);
387
388         /*
389          * Set keep-alive timeout in seconds granularity (ms * 1000)
390          * and add a grace period for controller kato enforcement
391          */
392         cmd.connect.kato = ctrl->opts->discovery_nqn ? 0 :
393                 cpu_to_le32((ctrl->kato + NVME_KATO_GRACE) * 1000);
394
395         data = kzalloc(sizeof(*data), GFP_KERNEL);
396         if (!data)
397                 return -ENOMEM;
398
399         uuid_copy(&data->hostid, &ctrl->opts->host->id);
400         data->cntlid = cpu_to_le16(0xffff);
401         strncpy(data->subsysnqn, ctrl->opts->subsysnqn, NVMF_NQN_SIZE);
402         strncpy(data->hostnqn, ctrl->opts->host->nqn, NVMF_NQN_SIZE);
403
404         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, &res,
405                         data, sizeof(*data), 0, NVME_QID_ANY, 1,
406                         BLK_MQ_REQ_RESERVED | BLK_MQ_REQ_NOWAIT);
407         if (ret) {
408                 nvmf_log_connect_error(ctrl, ret, le32_to_cpu(res.u32),
409                                        &cmd, data);
410                 goto out_free_data;
411         }
412
413         ctrl->cntlid = le16_to_cpu(res.u16);
414
415 out_free_data:
416         kfree(data);
417         return ret;
418 }
419 EXPORT_SYMBOL_GPL(nvmf_connect_admin_queue);
420
421 /**
422  * nvmf_connect_io_queue() - NVMe Fabrics I/O Queue "Connect"
423  *                           API function.
424  * @ctrl:       Host nvme controller instance used to establish an
425  *              NVMe I/O queue connection to the already allocated NVMe
426  *              controller on the target system.
427  * @qid:        NVMe I/O queue number for the new I/O connection between
428  *              host and target (note qid == 0 is illegal as this is
429  *              the Admin queue, per NVMe standard).
430  *
431  * This function issues a fabrics-protocol connection
432  * of a NVMe I/O queue (via NVMe Fabrics "Connect" command)
433  * between the host system device and the allocated NVMe controller
434  * on the target system.
435  *
436  * Return:
437  *      0: success
438  *      > 0: NVMe error status code
439  *      < 0: Linux errno error code
440  */
441 int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid)
442 {
443         struct nvme_command cmd;
444         struct nvmf_connect_data *data;
445         union nvme_result res;
446         int ret;
447
448         memset(&cmd, 0, sizeof(cmd));
449         cmd.connect.opcode = nvme_fabrics_command;
450         cmd.connect.fctype = nvme_fabrics_type_connect;
451         cmd.connect.qid = cpu_to_le16(qid);
452         cmd.connect.sqsize = cpu_to_le16(ctrl->sqsize);
453
454         data = kzalloc(sizeof(*data), GFP_KERNEL);
455         if (!data)
456                 return -ENOMEM;
457
458         uuid_copy(&data->hostid, &ctrl->opts->host->id);
459         data->cntlid = cpu_to_le16(ctrl->cntlid);
460         strncpy(data->subsysnqn, ctrl->opts->subsysnqn, NVMF_NQN_SIZE);
461         strncpy(data->hostnqn, ctrl->opts->host->nqn, NVMF_NQN_SIZE);
462
463         ret = __nvme_submit_sync_cmd(ctrl->connect_q, &cmd, &res,
464                         data, sizeof(*data), 0, qid, 1,
465                         BLK_MQ_REQ_RESERVED | BLK_MQ_REQ_NOWAIT);
466         if (ret) {
467                 nvmf_log_connect_error(ctrl, ret, le32_to_cpu(res.u32),
468                                        &cmd, data);
469         }
470         kfree(data);
471         return ret;
472 }
473 EXPORT_SYMBOL_GPL(nvmf_connect_io_queue);
474
475 bool nvmf_should_reconnect(struct nvme_ctrl *ctrl)
476 {
477         if (ctrl->opts->max_reconnects == -1 ||
478             ctrl->nr_reconnects < ctrl->opts->max_reconnects)
479                 return true;
480
481         return false;
482 }
483 EXPORT_SYMBOL_GPL(nvmf_should_reconnect);
484
485 /**
486  * nvmf_register_transport() - NVMe Fabrics Library registration function.
487  * @ops:        Transport ops instance to be registered to the
488  *              common fabrics library.
489  *
490  * API function that registers the type of specific transport fabric
491  * being implemented to the common NVMe fabrics library. Part of
492  * the overall init sequence of starting up a fabrics driver.
493  */
494 int nvmf_register_transport(struct nvmf_transport_ops *ops)
495 {
496         if (!ops->create_ctrl)
497                 return -EINVAL;
498
499         down_write(&nvmf_transports_rwsem);
500         list_add_tail(&ops->entry, &nvmf_transports);
501         up_write(&nvmf_transports_rwsem);
502
503         return 0;
504 }
505 EXPORT_SYMBOL_GPL(nvmf_register_transport);
506
507 /**
508  * nvmf_unregister_transport() - NVMe Fabrics Library unregistration function.
509  * @ops:        Transport ops instance to be unregistered from the
510  *              common fabrics library.
511  *
512  * Fabrics API function that unregisters the type of specific transport
513  * fabric being implemented from the common NVMe fabrics library.
514  * Part of the overall exit sequence of unloading the implemented driver.
515  */
516 void nvmf_unregister_transport(struct nvmf_transport_ops *ops)
517 {
518         down_write(&nvmf_transports_rwsem);
519         list_del(&ops->entry);
520         up_write(&nvmf_transports_rwsem);
521 }
522 EXPORT_SYMBOL_GPL(nvmf_unregister_transport);
523
524 static struct nvmf_transport_ops *nvmf_lookup_transport(
525                 struct nvmf_ctrl_options *opts)
526 {
527         struct nvmf_transport_ops *ops;
528
529         lockdep_assert_held(&nvmf_transports_rwsem);
530
531         list_for_each_entry(ops, &nvmf_transports, entry) {
532                 if (strcmp(ops->name, opts->transport) == 0)
533                         return ops;
534         }
535
536         return NULL;
537 }
538
539 /*
540  * For something we're not in a state to send to the device the default action
541  * is to busy it and retry it after the controller state is recovered.  However,
542  * if the controller is deleting or if anything is marked for failfast or
543  * nvme multipath it is immediately failed.
544  *
545  * Note: commands used to initialize the controller will be marked for failfast.
546  * Note: nvme cli/ioctl commands are marked for failfast.
547  */
548 blk_status_t nvmf_fail_nonready_command(struct nvme_ctrl *ctrl,
549                 struct request *rq)
550 {
551         if (ctrl->state != NVME_CTRL_DELETING &&
552             ctrl->state != NVME_CTRL_DEAD &&
553             !blk_noretry_request(rq) && !(rq->cmd_flags & REQ_NVME_MPATH))
554                 return BLK_STS_RESOURCE;
555         nvme_req(rq)->status = NVME_SC_ABORT_REQ;
556         return BLK_STS_IOERR;
557 }
558 EXPORT_SYMBOL_GPL(nvmf_fail_nonready_command);
559
560 bool __nvmf_check_ready(struct nvme_ctrl *ctrl, struct request *rq,
561                 bool queue_live)
562 {
563         struct nvme_request *req = nvme_req(rq);
564
565         /*
566          * If we are in some state of setup or teardown only allow
567          * internally generated commands.
568          */
569         if (!blk_rq_is_passthrough(rq) || (req->flags & NVME_REQ_USERCMD))
570                 return false;
571
572         /*
573          * Only allow commands on a live queue, except for the connect command,
574          * which is require to set the queue live in the appropinquate states.
575          */
576         switch (ctrl->state) {
577         case NVME_CTRL_NEW:
578         case NVME_CTRL_CONNECTING:
579                 if (req->cmd->common.opcode == nvme_fabrics_command &&
580                     req->cmd->fabrics.fctype == nvme_fabrics_type_connect)
581                         return true;
582                 break;
583         default:
584                 break;
585         case NVME_CTRL_DEAD:
586                 return false;
587         }
588
589         return queue_live;
590 }
591 EXPORT_SYMBOL_GPL(__nvmf_check_ready);
592
593 static const match_table_t opt_tokens = {
594         { NVMF_OPT_TRANSPORT,           "transport=%s"          },
595         { NVMF_OPT_TRADDR,              "traddr=%s"             },
596         { NVMF_OPT_TRSVCID,             "trsvcid=%s"            },
597         { NVMF_OPT_NQN,                 "nqn=%s"                },
598         { NVMF_OPT_QUEUE_SIZE,          "queue_size=%d"         },
599         { NVMF_OPT_NR_IO_QUEUES,        "nr_io_queues=%d"       },
600         { NVMF_OPT_RECONNECT_DELAY,     "reconnect_delay=%d"    },
601         { NVMF_OPT_CTRL_LOSS_TMO,       "ctrl_loss_tmo=%d"      },
602         { NVMF_OPT_KATO,                "keep_alive_tmo=%d"     },
603         { NVMF_OPT_HOSTNQN,             "hostnqn=%s"            },
604         { NVMF_OPT_HOST_TRADDR,         "host_traddr=%s"        },
605         { NVMF_OPT_HOST_ID,             "hostid=%s"             },
606         { NVMF_OPT_DUP_CONNECT,         "duplicate_connect"     },
607         { NVMF_OPT_ERR,                 NULL                    }
608 };
609
610 static int nvmf_parse_options(struct nvmf_ctrl_options *opts,
611                 const char *buf)
612 {
613         substring_t args[MAX_OPT_ARGS];
614         char *options, *o, *p;
615         int token, ret = 0;
616         size_t nqnlen  = 0;
617         int ctrl_loss_tmo = NVMF_DEF_CTRL_LOSS_TMO;
618         uuid_t hostid;
619
620         /* Set defaults */
621         opts->queue_size = NVMF_DEF_QUEUE_SIZE;
622         opts->nr_io_queues = num_online_cpus();
623         opts->reconnect_delay = NVMF_DEF_RECONNECT_DELAY;
624         opts->kato = NVME_DEFAULT_KATO;
625         opts->duplicate_connect = false;
626
627         options = o = kstrdup(buf, GFP_KERNEL);
628         if (!options)
629                 return -ENOMEM;
630
631         uuid_gen(&hostid);
632
633         while ((p = strsep(&o, ",\n")) != NULL) {
634                 if (!*p)
635                         continue;
636
637                 token = match_token(p, opt_tokens, args);
638                 opts->mask |= token;
639                 switch (token) {
640                 case NVMF_OPT_TRANSPORT:
641                         p = match_strdup(args);
642                         if (!p) {
643                                 ret = -ENOMEM;
644                                 goto out;
645                         }
646                         kfree(opts->transport);
647                         opts->transport = p;
648                         break;
649                 case NVMF_OPT_NQN:
650                         p = match_strdup(args);
651                         if (!p) {
652                                 ret = -ENOMEM;
653                                 goto out;
654                         }
655                         kfree(opts->subsysnqn);
656                         opts->subsysnqn = p;
657                         nqnlen = strlen(opts->subsysnqn);
658                         if (nqnlen >= NVMF_NQN_SIZE) {
659                                 pr_err("%s needs to be < %d bytes\n",
660                                         opts->subsysnqn, NVMF_NQN_SIZE);
661                                 ret = -EINVAL;
662                                 goto out;
663                         }
664                         opts->discovery_nqn =
665                                 !(strcmp(opts->subsysnqn,
666                                          NVME_DISC_SUBSYS_NAME));
667                         break;
668                 case NVMF_OPT_TRADDR:
669                         p = match_strdup(args);
670                         if (!p) {
671                                 ret = -ENOMEM;
672                                 goto out;
673                         }
674                         kfree(opts->traddr);
675                         opts->traddr = p;
676                         break;
677                 case NVMF_OPT_TRSVCID:
678                         p = match_strdup(args);
679                         if (!p) {
680                                 ret = -ENOMEM;
681                                 goto out;
682                         }
683                         kfree(opts->trsvcid);
684                         opts->trsvcid = p;
685                         break;
686                 case NVMF_OPT_QUEUE_SIZE:
687                         if (match_int(args, &token)) {
688                                 ret = -EINVAL;
689                                 goto out;
690                         }
691                         if (token < NVMF_MIN_QUEUE_SIZE ||
692                             token > NVMF_MAX_QUEUE_SIZE) {
693                                 pr_err("Invalid queue_size %d\n", token);
694                                 ret = -EINVAL;
695                                 goto out;
696                         }
697                         opts->queue_size = token;
698                         break;
699                 case NVMF_OPT_NR_IO_QUEUES:
700                         if (match_int(args, &token)) {
701                                 ret = -EINVAL;
702                                 goto out;
703                         }
704                         if (token <= 0) {
705                                 pr_err("Invalid number of IOQs %d\n", token);
706                                 ret = -EINVAL;
707                                 goto out;
708                         }
709                         if (opts->discovery_nqn) {
710                                 pr_debug("Ignoring nr_io_queues value for discovery controller\n");
711                                 break;
712                         }
713
714                         opts->nr_io_queues = min_t(unsigned int,
715                                         num_online_cpus(), token);
716                         break;
717                 case NVMF_OPT_KATO:
718                         if (match_int(args, &token)) {
719                                 ret = -EINVAL;
720                                 goto out;
721                         }
722
723                         if (token < 0) {
724                                 pr_err("Invalid keep_alive_tmo %d\n", token);
725                                 ret = -EINVAL;
726                                 goto out;
727                         } else if (token == 0 && !opts->discovery_nqn) {
728                                 /* Allowed for debug */
729                                 pr_warn("keep_alive_tmo 0 won't execute keep alives!!!\n");
730                         }
731                         opts->kato = token;
732
733                         if (opts->discovery_nqn && opts->kato) {
734                                 pr_err("Discovery controllers cannot accept KATO != 0\n");
735                                 ret = -EINVAL;
736                                 goto out;
737                         }
738
739                         break;
740                 case NVMF_OPT_CTRL_LOSS_TMO:
741                         if (match_int(args, &token)) {
742                                 ret = -EINVAL;
743                                 goto out;
744                         }
745
746                         if (token < 0)
747                                 pr_warn("ctrl_loss_tmo < 0 will reconnect forever\n");
748                         ctrl_loss_tmo = token;
749                         break;
750                 case NVMF_OPT_HOSTNQN:
751                         if (opts->host) {
752                                 pr_err("hostnqn already user-assigned: %s\n",
753                                        opts->host->nqn);
754                                 ret = -EADDRINUSE;
755                                 goto out;
756                         }
757                         p = match_strdup(args);
758                         if (!p) {
759                                 ret = -ENOMEM;
760                                 goto out;
761                         }
762                         nqnlen = strlen(p);
763                         if (nqnlen >= NVMF_NQN_SIZE) {
764                                 pr_err("%s needs to be < %d bytes\n",
765                                         p, NVMF_NQN_SIZE);
766                                 kfree(p);
767                                 ret = -EINVAL;
768                                 goto out;
769                         }
770                         nvmf_host_put(opts->host);
771                         opts->host = nvmf_host_add(p);
772                         kfree(p);
773                         if (!opts->host) {
774                                 ret = -ENOMEM;
775                                 goto out;
776                         }
777                         break;
778                 case NVMF_OPT_RECONNECT_DELAY:
779                         if (match_int(args, &token)) {
780                                 ret = -EINVAL;
781                                 goto out;
782                         }
783                         if (token <= 0) {
784                                 pr_err("Invalid reconnect_delay %d\n", token);
785                                 ret = -EINVAL;
786                                 goto out;
787                         }
788                         opts->reconnect_delay = token;
789                         break;
790                 case NVMF_OPT_HOST_TRADDR:
791                         p = match_strdup(args);
792                         if (!p) {
793                                 ret = -ENOMEM;
794                                 goto out;
795                         }
796                         kfree(opts->host_traddr);
797                         opts->host_traddr = p;
798                         break;
799                 case NVMF_OPT_HOST_ID:
800                         p = match_strdup(args);
801                         if (!p) {
802                                 ret = -ENOMEM;
803                                 goto out;
804                         }
805                         ret = uuid_parse(p, &hostid);
806                         if (ret) {
807                                 pr_err("Invalid hostid %s\n", p);
808                                 ret = -EINVAL;
809                                 kfree(p);
810                                 goto out;
811                         }
812                         kfree(p);
813                         break;
814                 case NVMF_OPT_DUP_CONNECT:
815                         opts->duplicate_connect = true;
816                         break;
817                 default:
818                         pr_warn("unknown parameter or missing value '%s' in ctrl creation request\n",
819                                 p);
820                         ret = -EINVAL;
821                         goto out;
822                 }
823         }
824
825         if (opts->discovery_nqn) {
826                 opts->kato = 0;
827                 opts->nr_io_queues = 0;
828                 opts->duplicate_connect = true;
829         }
830         if (ctrl_loss_tmo < 0)
831                 opts->max_reconnects = -1;
832         else
833                 opts->max_reconnects = DIV_ROUND_UP(ctrl_loss_tmo,
834                                                 opts->reconnect_delay);
835
836         if (!opts->host) {
837                 kref_get(&nvmf_default_host->ref);
838                 opts->host = nvmf_default_host;
839         }
840
841         uuid_copy(&opts->host->id, &hostid);
842
843 out:
844         kfree(options);
845         return ret;
846 }
847
848 static int nvmf_check_required_opts(struct nvmf_ctrl_options *opts,
849                 unsigned int required_opts)
850 {
851         if ((opts->mask & required_opts) != required_opts) {
852                 int i;
853
854                 for (i = 0; i < ARRAY_SIZE(opt_tokens); i++) {
855                         if ((opt_tokens[i].token & required_opts) &&
856                             !(opt_tokens[i].token & opts->mask)) {
857                                 pr_warn("missing parameter '%s'\n",
858                                         opt_tokens[i].pattern);
859                         }
860                 }
861
862                 return -EINVAL;
863         }
864
865         return 0;
866 }
867
868 static int nvmf_check_allowed_opts(struct nvmf_ctrl_options *opts,
869                 unsigned int allowed_opts)
870 {
871         if (opts->mask & ~allowed_opts) {
872                 int i;
873
874                 for (i = 0; i < ARRAY_SIZE(opt_tokens); i++) {
875                         if ((opt_tokens[i].token & opts->mask) &&
876                             (opt_tokens[i].token & ~allowed_opts)) {
877                                 pr_warn("invalid parameter '%s'\n",
878                                         opt_tokens[i].pattern);
879                         }
880                 }
881
882                 return -EINVAL;
883         }
884
885         return 0;
886 }
887
888 void nvmf_free_options(struct nvmf_ctrl_options *opts)
889 {
890         nvmf_host_put(opts->host);
891         kfree(opts->transport);
892         kfree(opts->traddr);
893         kfree(opts->trsvcid);
894         kfree(opts->subsysnqn);
895         kfree(opts->host_traddr);
896         kfree(opts);
897 }
898 EXPORT_SYMBOL_GPL(nvmf_free_options);
899
900 #define NVMF_REQUIRED_OPTS      (NVMF_OPT_TRANSPORT | NVMF_OPT_NQN)
901 #define NVMF_ALLOWED_OPTS       (NVMF_OPT_QUEUE_SIZE | NVMF_OPT_NR_IO_QUEUES | \
902                                  NVMF_OPT_KATO | NVMF_OPT_HOSTNQN | \
903                                  NVMF_OPT_HOST_ID | NVMF_OPT_DUP_CONNECT)
904
905 static struct nvme_ctrl *
906 nvmf_create_ctrl(struct device *dev, const char *buf, size_t count)
907 {
908         struct nvmf_ctrl_options *opts;
909         struct nvmf_transport_ops *ops;
910         struct nvme_ctrl *ctrl;
911         int ret;
912
913         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
914         if (!opts)
915                 return ERR_PTR(-ENOMEM);
916
917         ret = nvmf_parse_options(opts, buf);
918         if (ret)
919                 goto out_free_opts;
920
921
922         request_module("nvme-%s", opts->transport);
923
924         /*
925          * Check the generic options first as we need a valid transport for
926          * the lookup below.  Then clear the generic flags so that transport
927          * drivers don't have to care about them.
928          */
929         ret = nvmf_check_required_opts(opts, NVMF_REQUIRED_OPTS);
930         if (ret)
931                 goto out_free_opts;
932         opts->mask &= ~NVMF_REQUIRED_OPTS;
933
934         down_read(&nvmf_transports_rwsem);
935         ops = nvmf_lookup_transport(opts);
936         if (!ops) {
937                 pr_info("no handler found for transport %s.\n",
938                         opts->transport);
939                 ret = -EINVAL;
940                 goto out_unlock;
941         }
942
943         if (!try_module_get(ops->module)) {
944                 ret = -EBUSY;
945                 goto out_unlock;
946         }
947         up_read(&nvmf_transports_rwsem);
948
949         ret = nvmf_check_required_opts(opts, ops->required_opts);
950         if (ret)
951                 goto out_module_put;
952         ret = nvmf_check_allowed_opts(opts, NVMF_ALLOWED_OPTS |
953                                 ops->allowed_opts | ops->required_opts);
954         if (ret)
955                 goto out_module_put;
956
957         ctrl = ops->create_ctrl(dev, opts);
958         if (IS_ERR(ctrl)) {
959                 ret = PTR_ERR(ctrl);
960                 goto out_module_put;
961         }
962
963         module_put(ops->module);
964         return ctrl;
965
966 out_module_put:
967         module_put(ops->module);
968         goto out_free_opts;
969 out_unlock:
970         up_read(&nvmf_transports_rwsem);
971 out_free_opts:
972         nvmf_free_options(opts);
973         return ERR_PTR(ret);
974 }
975
976 static struct class *nvmf_class;
977 static struct device *nvmf_device;
978 static DEFINE_MUTEX(nvmf_dev_mutex);
979
980 static ssize_t nvmf_dev_write(struct file *file, const char __user *ubuf,
981                 size_t count, loff_t *pos)
982 {
983         struct seq_file *seq_file = file->private_data;
984         struct nvme_ctrl *ctrl;
985         const char *buf;
986         int ret = 0;
987
988         if (count > PAGE_SIZE)
989                 return -ENOMEM;
990
991         buf = memdup_user_nul(ubuf, count);
992         if (IS_ERR(buf))
993                 return PTR_ERR(buf);
994
995         mutex_lock(&nvmf_dev_mutex);
996         if (seq_file->private) {
997                 ret = -EINVAL;
998                 goto out_unlock;
999         }
1000
1001         ctrl = nvmf_create_ctrl(nvmf_device, buf, count);
1002         if (IS_ERR(ctrl)) {
1003                 ret = PTR_ERR(ctrl);
1004                 goto out_unlock;
1005         }
1006
1007         seq_file->private = ctrl;
1008
1009 out_unlock:
1010         mutex_unlock(&nvmf_dev_mutex);
1011         kfree(buf);
1012         return ret ? ret : count;
1013 }
1014
1015 static int nvmf_dev_show(struct seq_file *seq_file, void *private)
1016 {
1017         struct nvme_ctrl *ctrl;
1018         int ret = 0;
1019
1020         mutex_lock(&nvmf_dev_mutex);
1021         ctrl = seq_file->private;
1022         if (!ctrl) {
1023                 ret = -EINVAL;
1024                 goto out_unlock;
1025         }
1026
1027         seq_printf(seq_file, "instance=%d,cntlid=%d\n",
1028                         ctrl->instance, ctrl->cntlid);
1029
1030 out_unlock:
1031         mutex_unlock(&nvmf_dev_mutex);
1032         return ret;
1033 }
1034
1035 static int nvmf_dev_open(struct inode *inode, struct file *file)
1036 {
1037         /*
1038          * The miscdevice code initializes file->private_data, but doesn't
1039          * make use of it later.
1040          */
1041         file->private_data = NULL;
1042         return single_open(file, nvmf_dev_show, NULL);
1043 }
1044
1045 static int nvmf_dev_release(struct inode *inode, struct file *file)
1046 {
1047         struct seq_file *seq_file = file->private_data;
1048         struct nvme_ctrl *ctrl = seq_file->private;
1049
1050         if (ctrl)
1051                 nvme_put_ctrl(ctrl);
1052         return single_release(inode, file);
1053 }
1054
1055 static const struct file_operations nvmf_dev_fops = {
1056         .owner          = THIS_MODULE,
1057         .write          = nvmf_dev_write,
1058         .read           = seq_read,
1059         .open           = nvmf_dev_open,
1060         .release        = nvmf_dev_release,
1061 };
1062
1063 static struct miscdevice nvmf_misc = {
1064         .minor          = MISC_DYNAMIC_MINOR,
1065         .name           = "nvme-fabrics",
1066         .fops           = &nvmf_dev_fops,
1067 };
1068
1069 static int __init nvmf_init(void)
1070 {
1071         int ret;
1072
1073         nvmf_default_host = nvmf_host_default();
1074         if (!nvmf_default_host)
1075                 return -ENOMEM;
1076
1077         nvmf_class = class_create(THIS_MODULE, "nvme-fabrics");
1078         if (IS_ERR(nvmf_class)) {
1079                 pr_err("couldn't register class nvme-fabrics\n");
1080                 ret = PTR_ERR(nvmf_class);
1081                 goto out_free_host;
1082         }
1083
1084         nvmf_device =
1085                 device_create(nvmf_class, NULL, MKDEV(0, 0), NULL, "ctl");
1086         if (IS_ERR(nvmf_device)) {
1087                 pr_err("couldn't create nvme-fabris device!\n");
1088                 ret = PTR_ERR(nvmf_device);
1089                 goto out_destroy_class;
1090         }
1091
1092         ret = misc_register(&nvmf_misc);
1093         if (ret) {
1094                 pr_err("couldn't register misc device: %d\n", ret);
1095                 goto out_destroy_device;
1096         }
1097
1098         return 0;
1099
1100 out_destroy_device:
1101         device_destroy(nvmf_class, MKDEV(0, 0));
1102 out_destroy_class:
1103         class_destroy(nvmf_class);
1104 out_free_host:
1105         nvmf_host_put(nvmf_default_host);
1106         return ret;
1107 }
1108
1109 static void __exit nvmf_exit(void)
1110 {
1111         misc_deregister(&nvmf_misc);
1112         device_destroy(nvmf_class, MKDEV(0, 0));
1113         class_destroy(nvmf_class);
1114         nvmf_host_put(nvmf_default_host);
1115
1116         BUILD_BUG_ON(sizeof(struct nvmf_connect_command) != 64);
1117         BUILD_BUG_ON(sizeof(struct nvmf_property_get_command) != 64);
1118         BUILD_BUG_ON(sizeof(struct nvmf_property_set_command) != 64);
1119         BUILD_BUG_ON(sizeof(struct nvmf_connect_data) != 1024);
1120 }
1121
1122 MODULE_LICENSE("GPL v2");
1123
1124 module_init(nvmf_init);
1125 module_exit(nvmf_exit);