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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * RDMA Network Block Driver
4 *
5 * Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved.
6 * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
7 * Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved.
8 */
9#undef pr_fmt
10#define pr_fmt(fmt) KBUILD_MODNAME " L" __stringify(__LINE__) ": " fmt
11
12#include <linux/module.h>
13#include <linux/blkdev.h>
14
15#include "rnbd-srv.h"
16#include "rnbd-srv-dev.h"
17
18MODULE_DESCRIPTION("RDMA Network Block Device Server");
19MODULE_LICENSE("GPL");
20
21static u16 port_nr = RTRS_PORT;
22
23module_param_named(port_nr, port_nr, ushort, 0444);
24MODULE_PARM_DESC(port_nr,
25 "The port number the server is listening on (default: "
26 __stringify(RTRS_PORT)")");
27
28#define DEFAULT_DEV_SEARCH_PATH "/"
29
30static char dev_search_path[PATH_MAX] = DEFAULT_DEV_SEARCH_PATH;
31
32static int dev_search_path_set(const char *val, const struct kernel_param *kp)
33{
34 const char *p = strrchr(val, '\n') ? : val + strlen(val);
35
36 if (strlen(val) >= sizeof(dev_search_path))
37 return -EINVAL;
38
39 snprintf(dev_search_path, sizeof(dev_search_path), "%.*s",
40 (int)(p - val), val);
41
42 pr_info("dev_search_path changed to '%s'\n", dev_search_path);
43
44 return 0;
45}
46
47static struct kparam_string dev_search_path_kparam_str = {
48 .maxlen = sizeof(dev_search_path),
49 .string = dev_search_path
50};
51
52static const struct kernel_param_ops dev_search_path_ops = {
53 .set = dev_search_path_set,
54 .get = param_get_string,
55};
56
57module_param_cb(dev_search_path, &dev_search_path_ops,
58 &dev_search_path_kparam_str, 0444);
59MODULE_PARM_DESC(dev_search_path,
60 "Sets the dev_search_path. When a device is mapped this path is prepended to the device path from the map device operation. If %SESSNAME% is specified in a path, then device will be searched in a session namespace. (default: "
61 DEFAULT_DEV_SEARCH_PATH ")");
62
63static DEFINE_MUTEX(sess_lock);
64static DEFINE_SPINLOCK(dev_lock);
65
66static LIST_HEAD(sess_list);
67static LIST_HEAD(dev_list);
68
69struct rnbd_io_private {
70 struct rtrs_srv_op *id;
71 struct rnbd_srv_sess_dev *sess_dev;
72};
73
74static void rnbd_sess_dev_release(struct kref *kref)
75{
76 struct rnbd_srv_sess_dev *sess_dev;
77
78 sess_dev = container_of(kref, struct rnbd_srv_sess_dev, kref);
79 complete(sess_dev->destroy_comp);
80}
81
82static inline void rnbd_put_sess_dev(struct rnbd_srv_sess_dev *sess_dev)
83{
84 kref_put(&sess_dev->kref, rnbd_sess_dev_release);
85}
86
87void rnbd_endio(void *priv, int error)
88{
89 struct rnbd_io_private *rnbd_priv = priv;
90 struct rnbd_srv_sess_dev *sess_dev = rnbd_priv->sess_dev;
91
92 rnbd_put_sess_dev(sess_dev);
93
94 rtrs_srv_resp_rdma(rnbd_priv->id, error);
95
96 kfree(priv);
97}
98
99static struct rnbd_srv_sess_dev *
100rnbd_get_sess_dev(int dev_id, struct rnbd_srv_session *srv_sess)
101{
102 struct rnbd_srv_sess_dev *sess_dev;
103 int ret = 0;
104
105 rcu_read_lock();
106 sess_dev = xa_load(&srv_sess->index_idr, dev_id);
107 if (likely(sess_dev))
108 ret = kref_get_unless_zero(&sess_dev->kref);
109 rcu_read_unlock();
110
111 if (!sess_dev || !ret)
112 return ERR_PTR(-ENXIO);
113
114 return sess_dev;
115}
116
117static int process_rdma(struct rtrs_srv *sess,
118 struct rnbd_srv_session *srv_sess,
119 struct rtrs_srv_op *id, void *data, u32 datalen,
120 const void *usr, size_t usrlen)
121{
122 const struct rnbd_msg_io *msg = usr;
123 struct rnbd_io_private *priv;
124 struct rnbd_srv_sess_dev *sess_dev;
125 u32 dev_id;
126 int err;
127 struct rnbd_dev_blk_io *io;
128 struct bio *bio;
129 short prio;
130
131 priv = kmalloc(sizeof(*priv), GFP_KERNEL);
132 if (!priv)
133 return -ENOMEM;
134
135 dev_id = le32_to_cpu(msg->device_id);
136
137 sess_dev = rnbd_get_sess_dev(dev_id, srv_sess);
138 if (IS_ERR(sess_dev)) {
139 pr_err_ratelimited("Got I/O request on session %s for unknown device id %d\n",
140 srv_sess->sessname, dev_id);
141 err = -ENOTCONN;
142 goto err;
143 }
144
145 priv->sess_dev = sess_dev;
146 priv->id = id;
147
148 /* Generate bio with pages pointing to the rdma buffer */
149 bio = rnbd_bio_map_kern(data, sess_dev->rnbd_dev->ibd_bio_set, datalen, GFP_KERNEL);
150 if (IS_ERR(bio)) {
151 err = PTR_ERR(bio);
152 rnbd_srv_err(sess_dev, "Failed to generate bio, err: %d\n", err);
153 goto sess_dev_put;
154 }
155
156 io = container_of(bio, struct rnbd_dev_blk_io, bio);
157 io->dev = sess_dev->rnbd_dev;
158 io->priv = priv;
159
160 bio->bi_end_io = rnbd_dev_bi_end_io;
161 bio->bi_private = io;
162 bio->bi_opf = rnbd_to_bio_flags(le32_to_cpu(msg->rw));
163 bio->bi_iter.bi_sector = le64_to_cpu(msg->sector);
164 bio->bi_iter.bi_size = le32_to_cpu(msg->bi_size);
165 prio = srv_sess->ver < RNBD_PROTO_VER_MAJOR ||
166 usrlen < sizeof(*msg) ? 0 : le16_to_cpu(msg->prio);
167 bio_set_prio(bio, prio);
168 bio_set_dev(bio, sess_dev->rnbd_dev->bdev);
169
170 submit_bio(bio);
171
172 return 0;
173
174sess_dev_put:
175 rnbd_put_sess_dev(sess_dev);
176err:
177 kfree(priv);
178 return err;
179}
180
181static void destroy_device(struct rnbd_srv_dev *dev)
182{
183 WARN_ONCE(!list_empty(&dev->sess_dev_list),
184 "Device %s is being destroyed but still in use!\n",
185 dev->id);
186
187 spin_lock(&dev_lock);
188 list_del(&dev->list);
189 spin_unlock(&dev_lock);
190
191 mutex_destroy(&dev->lock);
192 if (dev->dev_kobj.state_in_sysfs)
193 /*
194 * Destroy kobj only if it was really created.
195 */
196 rnbd_srv_destroy_dev_sysfs(dev);
197 else
198 kfree(dev);
199}
200
201static void destroy_device_cb(struct kref *kref)
202{
203 struct rnbd_srv_dev *dev;
204
205 dev = container_of(kref, struct rnbd_srv_dev, kref);
206
207 destroy_device(dev);
208}
209
210static void rnbd_put_srv_dev(struct rnbd_srv_dev *dev)
211{
212 kref_put(&dev->kref, destroy_device_cb);
213}
214
215void rnbd_destroy_sess_dev(struct rnbd_srv_sess_dev *sess_dev)
216{
217 DECLARE_COMPLETION_ONSTACK(dc);
218
219 xa_erase(&sess_dev->sess->index_idr, sess_dev->device_id);
220 synchronize_rcu();
221 sess_dev->destroy_comp = &dc;
222 rnbd_put_sess_dev(sess_dev);
223 wait_for_completion(&dc); /* wait for inflights to drop to zero */
224
225 rnbd_dev_close(sess_dev->rnbd_dev);
226 list_del(&sess_dev->sess_list);
227 mutex_lock(&sess_dev->dev->lock);
228 list_del(&sess_dev->dev_list);
229 if (sess_dev->open_flags & FMODE_WRITE)
230 sess_dev->dev->open_write_cnt--;
231 mutex_unlock(&sess_dev->dev->lock);
232
233 rnbd_put_srv_dev(sess_dev->dev);
234
235 rnbd_srv_info(sess_dev, "Device closed\n");
236 kfree(sess_dev);
237}
238
239static void destroy_sess(struct rnbd_srv_session *srv_sess)
240{
241 struct rnbd_srv_sess_dev *sess_dev, *tmp;
242
243 if (list_empty(&srv_sess->sess_dev_list))
244 goto out;
245
246 mutex_lock(&srv_sess->lock);
247 list_for_each_entry_safe(sess_dev, tmp, &srv_sess->sess_dev_list,
248 sess_list)
249 rnbd_srv_destroy_dev_session_sysfs(sess_dev);
250 mutex_unlock(&srv_sess->lock);
251
252out:
253 xa_destroy(&srv_sess->index_idr);
254 bioset_exit(&srv_sess->sess_bio_set);
255
256 pr_info("RTRS Session %s disconnected\n", srv_sess->sessname);
257
258 mutex_lock(&sess_lock);
259 list_del(&srv_sess->list);
260 mutex_unlock(&sess_lock);
261
262 mutex_destroy(&srv_sess->lock);
263 kfree(srv_sess);
264}
265
266static int create_sess(struct rtrs_srv *rtrs)
267{
268 struct rnbd_srv_session *srv_sess;
269 char sessname[NAME_MAX];
270 int err;
271
272 err = rtrs_srv_get_sess_name(rtrs, sessname, sizeof(sessname));
273 if (err) {
274 pr_err("rtrs_srv_get_sess_name(%s): %d\n", sessname, err);
275
276 return err;
277 }
278 srv_sess = kzalloc(sizeof(*srv_sess), GFP_KERNEL);
279 if (!srv_sess)
280 return -ENOMEM;
281
282 srv_sess->queue_depth = rtrs_srv_get_queue_depth(rtrs);
283 err = bioset_init(&srv_sess->sess_bio_set, srv_sess->queue_depth,
284 offsetof(struct rnbd_dev_blk_io, bio),
285 BIOSET_NEED_BVECS);
286 if (err) {
287 pr_err("Allocating srv_session for session %s failed\n",
288 sessname);
289 kfree(srv_sess);
290 return err;
291 }
292
293 xa_init_flags(&srv_sess->index_idr, XA_FLAGS_ALLOC);
294 INIT_LIST_HEAD(&srv_sess->sess_dev_list);
295 mutex_init(&srv_sess->lock);
296 mutex_lock(&sess_lock);
297 list_add(&srv_sess->list, &sess_list);
298 mutex_unlock(&sess_lock);
299
300 srv_sess->rtrs = rtrs;
301 strlcpy(srv_sess->sessname, sessname, sizeof(srv_sess->sessname));
302
303 rtrs_srv_set_sess_priv(rtrs, srv_sess);
304
305 return 0;
306}
307
308static int rnbd_srv_link_ev(struct rtrs_srv *rtrs,
309 enum rtrs_srv_link_ev ev, void *priv)
310{
311 struct rnbd_srv_session *srv_sess = priv;
312
313 switch (ev) {
314 case RTRS_SRV_LINK_EV_CONNECTED:
315 return create_sess(rtrs);
316
317 case RTRS_SRV_LINK_EV_DISCONNECTED:
318 if (WARN_ON_ONCE(!srv_sess))
319 return -EINVAL;
320
321 destroy_sess(srv_sess);
322 return 0;
323
324 default:
325 pr_warn("Received unknown RTRS session event %d from session %s\n",
326 ev, srv_sess->sessname);
327 return -EINVAL;
328 }
329}
330
331static int process_msg_close(struct rtrs_srv *rtrs,
332 struct rnbd_srv_session *srv_sess,
333 void *data, size_t datalen, const void *usr,
334 size_t usrlen)
335{
336 const struct rnbd_msg_close *close_msg = usr;
337 struct rnbd_srv_sess_dev *sess_dev;
338
339 sess_dev = rnbd_get_sess_dev(le32_to_cpu(close_msg->device_id),
340 srv_sess);
341 if (IS_ERR(sess_dev))
342 return 0;
343
344 rnbd_put_sess_dev(sess_dev);
345 mutex_lock(&srv_sess->lock);
346 rnbd_srv_destroy_dev_session_sysfs(sess_dev);
347 mutex_unlock(&srv_sess->lock);
348 return 0;
349}
350
351static int process_msg_open(struct rtrs_srv *rtrs,
352 struct rnbd_srv_session *srv_sess,
353 const void *msg, size_t len,
354 void *data, size_t datalen);
355
356static int process_msg_sess_info(struct rtrs_srv *rtrs,
357 struct rnbd_srv_session *srv_sess,
358 const void *msg, size_t len,
359 void *data, size_t datalen);
360
361static int rnbd_srv_rdma_ev(struct rtrs_srv *rtrs, void *priv,
362 struct rtrs_srv_op *id, int dir,
363 void *data, size_t datalen, const void *usr,
364 size_t usrlen)
365{
366 struct rnbd_srv_session *srv_sess = priv;
367 const struct rnbd_msg_hdr *hdr = usr;
368 int ret = 0;
369 u16 type;
370
371 if (WARN_ON_ONCE(!srv_sess))
372 return -ENODEV;
373
374 type = le16_to_cpu(hdr->type);
375
376 switch (type) {
377 case RNBD_MSG_IO:
378 return process_rdma(rtrs, srv_sess, id, data, datalen, usr,
379 usrlen);
380 case RNBD_MSG_CLOSE:
381 ret = process_msg_close(rtrs, srv_sess, data, datalen,
382 usr, usrlen);
383 break;
384 case RNBD_MSG_OPEN:
385 ret = process_msg_open(rtrs, srv_sess, usr, usrlen,
386 data, datalen);
387 break;
388 case RNBD_MSG_SESS_INFO:
389 ret = process_msg_sess_info(rtrs, srv_sess, usr, usrlen,
390 data, datalen);
391 break;
392 default:
393 pr_warn("Received unexpected message type %d with dir %d from session %s\n",
394 type, dir, srv_sess->sessname);
395 return -EINVAL;
396 }
397
398 rtrs_srv_resp_rdma(id, ret);
399 return 0;
400}
401
402static struct rnbd_srv_sess_dev
403*rnbd_sess_dev_alloc(struct rnbd_srv_session *srv_sess)
404{
405 struct rnbd_srv_sess_dev *sess_dev;
406 int error;
407
408 sess_dev = kzalloc(sizeof(*sess_dev), GFP_KERNEL);
409 if (!sess_dev)
410 return ERR_PTR(-ENOMEM);
411
412 error = xa_alloc(&srv_sess->index_idr, &sess_dev->device_id, sess_dev,
413 xa_limit_32b, GFP_NOWAIT);
414 if (error < 0) {
415 pr_warn("Allocating idr failed, err: %d\n", error);
416 kfree(sess_dev);
417 return ERR_PTR(error);
418 }
419
420 return sess_dev;
421}
422
423static struct rnbd_srv_dev *rnbd_srv_init_srv_dev(const char *id)
424{
425 struct rnbd_srv_dev *dev;
426
427 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
428 if (!dev)
429 return ERR_PTR(-ENOMEM);
430
431 strlcpy(dev->id, id, sizeof(dev->id));
432 kref_init(&dev->kref);
433 INIT_LIST_HEAD(&dev->sess_dev_list);
434 mutex_init(&dev->lock);
435
436 return dev;
437}
438
439static struct rnbd_srv_dev *
440rnbd_srv_find_or_add_srv_dev(struct rnbd_srv_dev *new_dev)
441{
442 struct rnbd_srv_dev *dev;
443
444 spin_lock(&dev_lock);
445 list_for_each_entry(dev, &dev_list, list) {
446 if (!strncmp(dev->id, new_dev->id, sizeof(dev->id))) {
447 if (!kref_get_unless_zero(&dev->kref))
448 /*
449 * We lost the race, device is almost dead.
450 * Continue traversing to find a valid one.
451 */
452 continue;
453 spin_unlock(&dev_lock);
454 return dev;
455 }
456 }
457 list_add(&new_dev->list, &dev_list);
458 spin_unlock(&dev_lock);
459
460 return new_dev;
461}
462
463static int rnbd_srv_check_update_open_perm(struct rnbd_srv_dev *srv_dev,
464 struct rnbd_srv_session *srv_sess,
465 enum rnbd_access_mode access_mode)
466{
467 int ret = -EPERM;
468
469 mutex_lock(&srv_dev->lock);
470
471 switch (access_mode) {
472 case RNBD_ACCESS_RO:
473 ret = 0;
474 break;
475 case RNBD_ACCESS_RW:
476 if (srv_dev->open_write_cnt == 0) {
477 srv_dev->open_write_cnt++;
478 ret = 0;
479 } else {
480 pr_err("Mapping device '%s' for session %s with RW permissions failed. Device already opened as 'RW' by %d client(s), access mode %s.\n",
481 srv_dev->id, srv_sess->sessname,
482 srv_dev->open_write_cnt,
483 rnbd_access_mode_str(access_mode));
484 }
485 break;
486 case RNBD_ACCESS_MIGRATION:
487 if (srv_dev->open_write_cnt < 2) {
488 srv_dev->open_write_cnt++;
489 ret = 0;
490 } else {
491 pr_err("Mapping device '%s' for session %s with migration permissions failed. Device already opened as 'RW' by %d client(s), access mode %s.\n",
492 srv_dev->id, srv_sess->sessname,
493 srv_dev->open_write_cnt,
494 rnbd_access_mode_str(access_mode));
495 }
496 break;
497 default:
498 pr_err("Received mapping request for device '%s' on session %s with invalid access mode: %d\n",
499 srv_dev->id, srv_sess->sessname, access_mode);
500 ret = -EINVAL;
501 }
502
503 mutex_unlock(&srv_dev->lock);
504
505 return ret;
506}
507
508static struct rnbd_srv_dev *
509rnbd_srv_get_or_create_srv_dev(struct rnbd_dev *rnbd_dev,
510 struct rnbd_srv_session *srv_sess,
511 enum rnbd_access_mode access_mode)
512{
513 int ret;
514 struct rnbd_srv_dev *new_dev, *dev;
515
516 new_dev = rnbd_srv_init_srv_dev(rnbd_dev->name);
517 if (IS_ERR(new_dev))
518 return new_dev;
519
520 dev = rnbd_srv_find_or_add_srv_dev(new_dev);
521 if (dev != new_dev)
522 kfree(new_dev);
523
524 ret = rnbd_srv_check_update_open_perm(dev, srv_sess, access_mode);
525 if (ret) {
526 rnbd_put_srv_dev(dev);
527 return ERR_PTR(ret);
528 }
529
530 return dev;
531}
532
533static void rnbd_srv_fill_msg_open_rsp(struct rnbd_msg_open_rsp *rsp,
534 struct rnbd_srv_sess_dev *sess_dev)
535{
536 struct rnbd_dev *rnbd_dev = sess_dev->rnbd_dev;
537
538 rsp->hdr.type = cpu_to_le16(RNBD_MSG_OPEN_RSP);
539 rsp->device_id =
540 cpu_to_le32(sess_dev->device_id);
541 rsp->nsectors =
542 cpu_to_le64(get_capacity(rnbd_dev->bdev->bd_disk));
543 rsp->logical_block_size =
544 cpu_to_le16(bdev_logical_block_size(rnbd_dev->bdev));
545 rsp->physical_block_size =
546 cpu_to_le16(bdev_physical_block_size(rnbd_dev->bdev));
547 rsp->max_segments =
548 cpu_to_le16(rnbd_dev_get_max_segs(rnbd_dev));
549 rsp->max_hw_sectors =
550 cpu_to_le32(rnbd_dev_get_max_hw_sects(rnbd_dev));
551 rsp->max_write_same_sectors =
552 cpu_to_le32(bdev_write_same(rnbd_dev->bdev));
553 rsp->max_discard_sectors =
554 cpu_to_le32(rnbd_dev_get_max_discard_sects(rnbd_dev));
555 rsp->discard_granularity =
556 cpu_to_le32(rnbd_dev_get_discard_granularity(rnbd_dev));
557 rsp->discard_alignment =
558 cpu_to_le32(rnbd_dev_get_discard_alignment(rnbd_dev));
559 rsp->secure_discard =
560 cpu_to_le16(rnbd_dev_get_secure_discard(rnbd_dev));
561 rsp->rotational =
562 !blk_queue_nonrot(bdev_get_queue(rnbd_dev->bdev));
563}
564
565static struct rnbd_srv_sess_dev *
566rnbd_srv_create_set_sess_dev(struct rnbd_srv_session *srv_sess,
567 const struct rnbd_msg_open *open_msg,
568 struct rnbd_dev *rnbd_dev, fmode_t open_flags,
569 struct rnbd_srv_dev *srv_dev)
570{
571 struct rnbd_srv_sess_dev *sdev = rnbd_sess_dev_alloc(srv_sess);
572
573 if (IS_ERR(sdev))
574 return sdev;
575
576 kref_init(&sdev->kref);
577
578 strlcpy(sdev->pathname, open_msg->dev_name, sizeof(sdev->pathname));
579
580 sdev->rnbd_dev = rnbd_dev;
581 sdev->sess = srv_sess;
582 sdev->dev = srv_dev;
583 sdev->open_flags = open_flags;
584 sdev->access_mode = open_msg->access_mode;
585
586 return sdev;
587}
588
589static char *rnbd_srv_get_full_path(struct rnbd_srv_session *srv_sess,
590 const char *dev_name)
591{
592 char *full_path;
593 char *a, *b;
594
595 full_path = kmalloc(PATH_MAX, GFP_KERNEL);
596 if (!full_path)
597 return ERR_PTR(-ENOMEM);
598
599 /*
600 * Replace %SESSNAME% with a real session name in order to
601 * create device namespace.
602 */
603 a = strnstr(dev_search_path, "%SESSNAME%", sizeof(dev_search_path));
604 if (a) {
605 int len = a - dev_search_path;
606
607 len = snprintf(full_path, PATH_MAX, "%.*s/%s/%s", len,
608 dev_search_path, srv_sess->sessname, dev_name);
609 if (len >= PATH_MAX) {
610 pr_err("Too long path: %s, %s, %s\n",
611 dev_search_path, srv_sess->sessname, dev_name);
612 kfree(full_path);
613 return ERR_PTR(-EINVAL);
614 }
615 } else {
616 snprintf(full_path, PATH_MAX, "%s/%s",
617 dev_search_path, dev_name);
618 }
619
620 /* eliminitate duplicated slashes */
621 a = strchr(full_path, '/');
622 b = a;
623 while (*b != '\0') {
624 if (*b == '/' && *a == '/') {
625 b++;
626 } else {
627 a++;
628 *a = *b;
629 b++;
630 }
631 }
632 a++;
633 *a = '\0';
634
635 return full_path;
636}
637
638static int process_msg_sess_info(struct rtrs_srv *rtrs,
639 struct rnbd_srv_session *srv_sess,
640 const void *msg, size_t len,
641 void *data, size_t datalen)
642{
643 const struct rnbd_msg_sess_info *sess_info_msg = msg;
644 struct rnbd_msg_sess_info_rsp *rsp = data;
645
646 srv_sess->ver = min_t(u8, sess_info_msg->ver, RNBD_PROTO_VER_MAJOR);
647 pr_debug("Session %s using protocol version %d (client version: %d, server version: %d)\n",
648 srv_sess->sessname, srv_sess->ver,
649 sess_info_msg->ver, RNBD_PROTO_VER_MAJOR);
650
651 rsp->hdr.type = cpu_to_le16(RNBD_MSG_SESS_INFO_RSP);
652 rsp->ver = srv_sess->ver;
653
654 return 0;
655}
656
657/**
658 * find_srv_sess_dev() - a dev is already opened by this name
659 * @srv_sess: the session to search.
660 * @dev_name: string containing the name of the device.
661 *
662 * Return struct rnbd_srv_sess_dev if srv_sess already opened the dev_name
663 * NULL if the session didn't open the device yet.
664 */
665static struct rnbd_srv_sess_dev *
666find_srv_sess_dev(struct rnbd_srv_session *srv_sess, const char *dev_name)
667{
668 struct rnbd_srv_sess_dev *sess_dev;
669
670 if (list_empty(&srv_sess->sess_dev_list))
671 return NULL;
672
673 list_for_each_entry(sess_dev, &srv_sess->sess_dev_list, sess_list)
674 if (!strcmp(sess_dev->pathname, dev_name))
675 return sess_dev;
676
677 return NULL;
678}
679
680static int process_msg_open(struct rtrs_srv *rtrs,
681 struct rnbd_srv_session *srv_sess,
682 const void *msg, size_t len,
683 void *data, size_t datalen)
684{
685 int ret;
686 struct rnbd_srv_dev *srv_dev;
687 struct rnbd_srv_sess_dev *srv_sess_dev;
688 const struct rnbd_msg_open *open_msg = msg;
689 fmode_t open_flags;
690 char *full_path;
691 struct rnbd_dev *rnbd_dev;
692 struct rnbd_msg_open_rsp *rsp = data;
693
694 pr_debug("Open message received: session='%s' path='%s' access_mode=%d\n",
695 srv_sess->sessname, open_msg->dev_name,
696 open_msg->access_mode);
697 open_flags = FMODE_READ;
698 if (open_msg->access_mode != RNBD_ACCESS_RO)
699 open_flags |= FMODE_WRITE;
700
701 mutex_lock(&srv_sess->lock);
702
703 srv_sess_dev = find_srv_sess_dev(srv_sess, open_msg->dev_name);
704 if (srv_sess_dev)
705 goto fill_response;
706
707 if ((strlen(dev_search_path) + strlen(open_msg->dev_name))
708 >= PATH_MAX) {
709 pr_err("Opening device for session %s failed, device path too long. '%s/%s' is longer than PATH_MAX (%d)\n",
710 srv_sess->sessname, dev_search_path, open_msg->dev_name,
711 PATH_MAX);
712 ret = -EINVAL;
713 goto reject;
714 }
715 if (strstr(open_msg->dev_name, "..")) {
716 pr_err("Opening device for session %s failed, device path %s contains relative path ..\n",
717 srv_sess->sessname, open_msg->dev_name);
718 ret = -EINVAL;
719 goto reject;
720 }
721 full_path = rnbd_srv_get_full_path(srv_sess, open_msg->dev_name);
722 if (IS_ERR(full_path)) {
723 ret = PTR_ERR(full_path);
724 pr_err("Opening device '%s' for client %s failed, failed to get device full path, err: %d\n",
725 open_msg->dev_name, srv_sess->sessname, ret);
726 goto reject;
727 }
728
729 rnbd_dev = rnbd_dev_open(full_path, open_flags,
730 &srv_sess->sess_bio_set);
731 if (IS_ERR(rnbd_dev)) {
732 pr_err("Opening device '%s' on session %s failed, failed to open the block device, err: %ld\n",
733 full_path, srv_sess->sessname, PTR_ERR(rnbd_dev));
734 ret = PTR_ERR(rnbd_dev);
735 goto free_path;
736 }
737
738 srv_dev = rnbd_srv_get_or_create_srv_dev(rnbd_dev, srv_sess,
739 open_msg->access_mode);
740 if (IS_ERR(srv_dev)) {
741 pr_err("Opening device '%s' on session %s failed, creating srv_dev failed, err: %ld\n",
742 full_path, srv_sess->sessname, PTR_ERR(srv_dev));
743 ret = PTR_ERR(srv_dev);
744 goto rnbd_dev_close;
745 }
746
747 srv_sess_dev = rnbd_srv_create_set_sess_dev(srv_sess, open_msg,
748 rnbd_dev, open_flags,
749 srv_dev);
750 if (IS_ERR(srv_sess_dev)) {
751 pr_err("Opening device '%s' on session %s failed, creating sess_dev failed, err: %ld\n",
752 full_path, srv_sess->sessname, PTR_ERR(srv_sess_dev));
753 ret = PTR_ERR(srv_sess_dev);
754 goto srv_dev_put;
755 }
756
757 /* Create the srv_dev sysfs files if they haven't been created yet. The
758 * reason to delay the creation is not to create the sysfs files before
759 * we are sure the device can be opened.
760 */
761 mutex_lock(&srv_dev->lock);
762 if (!srv_dev->dev_kobj.state_in_sysfs) {
763 ret = rnbd_srv_create_dev_sysfs(srv_dev, rnbd_dev->bdev,
764 rnbd_dev->name);
765 if (ret) {
766 mutex_unlock(&srv_dev->lock);
767 rnbd_srv_err(srv_sess_dev,
768 "Opening device failed, failed to create device sysfs files, err: %d\n",
769 ret);
770 goto free_srv_sess_dev;
771 }
772 }
773
774 ret = rnbd_srv_create_dev_session_sysfs(srv_sess_dev);
775 if (ret) {
776 mutex_unlock(&srv_dev->lock);
777 rnbd_srv_err(srv_sess_dev,
778 "Opening device failed, failed to create dev client sysfs files, err: %d\n",
779 ret);
780 goto free_srv_sess_dev;
781 }
782
783 list_add(&srv_sess_dev->dev_list, &srv_dev->sess_dev_list);
784 mutex_unlock(&srv_dev->lock);
785
786 list_add(&srv_sess_dev->sess_list, &srv_sess->sess_dev_list);
787
788 rnbd_srv_info(srv_sess_dev, "Opened device '%s'\n", srv_dev->id);
789
790 kfree(full_path);
791
792fill_response:
793 rnbd_srv_fill_msg_open_rsp(rsp, srv_sess_dev);
794 mutex_unlock(&srv_sess->lock);
795 return 0;
796
797free_srv_sess_dev:
798 xa_erase(&srv_sess->index_idr, srv_sess_dev->device_id);
799 synchronize_rcu();
800 kfree(srv_sess_dev);
801srv_dev_put:
802 if (open_msg->access_mode != RNBD_ACCESS_RO) {
803 mutex_lock(&srv_dev->lock);
804 srv_dev->open_write_cnt--;
805 mutex_unlock(&srv_dev->lock);
806 }
807 rnbd_put_srv_dev(srv_dev);
808rnbd_dev_close:
809 rnbd_dev_close(rnbd_dev);
810free_path:
811 kfree(full_path);
812reject:
813 mutex_unlock(&srv_sess->lock);
814 return ret;
815}
816
817static struct rtrs_srv_ctx *rtrs_ctx;
818
819static struct rtrs_srv_ops rtrs_ops;
820static int __init rnbd_srv_init_module(void)
821{
822 int err;
823
824 BUILD_BUG_ON(sizeof(struct rnbd_msg_hdr) != 4);
825 BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info) != 36);
826 BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info_rsp) != 36);
827 BUILD_BUG_ON(sizeof(struct rnbd_msg_open) != 264);
828 BUILD_BUG_ON(sizeof(struct rnbd_msg_close) != 8);
829 BUILD_BUG_ON(sizeof(struct rnbd_msg_open_rsp) != 56);
830 rtrs_ops = (struct rtrs_srv_ops) {
831 .rdma_ev = rnbd_srv_rdma_ev,
832 .link_ev = rnbd_srv_link_ev,
833 };
834 rtrs_ctx = rtrs_srv_open(&rtrs_ops, port_nr);
835 if (IS_ERR(rtrs_ctx)) {
836 err = PTR_ERR(rtrs_ctx);
837 pr_err("rtrs_srv_open(), err: %d\n", err);
838 return err;
839 }
840
841 err = rnbd_srv_create_sysfs_files();
842 if (err) {
843 pr_err("rnbd_srv_create_sysfs_files(), err: %d\n", err);
844 rtrs_srv_close(rtrs_ctx);
845 return err;
846 }
847
848 return 0;
849}
850
851static void __exit rnbd_srv_cleanup_module(void)
852{
853 rtrs_srv_close(rtrs_ctx);
854 WARN_ON(!list_empty(&sess_list));
855 rnbd_srv_destroy_sysfs_files();
856}
857
858module_init(rnbd_srv_init_module);
859module_exit(rnbd_srv_cleanup_module);