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 18 MODULE_DESCRIPTION("RDMA Network Block Device Server"); 19 MODULE_LICENSE("GPL"); 20 21 static u16 port_nr = RTRS_PORT; 22 23 module_param_named(port_nr, port_nr, ushort, 0444); 24 MODULE_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 30 static char dev_search_path[PATH_MAX] = DEFAULT_DEV_SEARCH_PATH; 31 32 static 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 47 static struct kparam_string dev_search_path_kparam_str = { 48 .maxlen = sizeof(dev_search_path), 49 .string = dev_search_path 50 }; 51 52 static const struct kernel_param_ops dev_search_path_ops = { 53 .set = dev_search_path_set, 54 .get = param_get_string, 55 }; 56 57 module_param_cb(dev_search_path, &dev_search_path_ops, 58 &dev_search_path_kparam_str, 0444); 59 MODULE_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 63 static DEFINE_MUTEX(sess_lock); 64 static DEFINE_SPINLOCK(dev_lock); 65 66 static LIST_HEAD(sess_list); 67 static LIST_HEAD(dev_list); 68 69 struct rnbd_io_private { 70 struct rtrs_srv_op *id; 71 struct rnbd_srv_sess_dev *sess_dev; 72 }; 73 74 static 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 82 static 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 87 void 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 99 static struct rnbd_srv_sess_dev * 100 rnbd_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 (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 } 116 117 static int process_rdma(struct rnbd_srv_session *srv_sess, 118 struct rtrs_srv_op *id, void *data, u32 datalen, 119 const void *usr, size_t usrlen) 120 { 121 const struct rnbd_msg_io *msg = usr; 122 struct rnbd_io_private *priv; 123 struct rnbd_srv_sess_dev *sess_dev; 124 u32 dev_id; 125 int err; 126 struct rnbd_dev_blk_io *io; 127 struct bio *bio; 128 short prio; 129 130 priv = kmalloc(sizeof(*priv), GFP_KERNEL); 131 if (!priv) 132 return -ENOMEM; 133 134 dev_id = le32_to_cpu(msg->device_id); 135 136 sess_dev = rnbd_get_sess_dev(dev_id, srv_sess); 137 if (IS_ERR(sess_dev)) { 138 pr_err_ratelimited("Got I/O request on session %s for unknown device id %d\n", 139 srv_sess->sessname, dev_id); 140 err = -ENOTCONN; 141 goto err; 142 } 143 144 priv->sess_dev = sess_dev; 145 priv->id = id; 146 147 /* Generate bio with pages pointing to the rdma buffer */ 148 bio = rnbd_bio_map_kern(data, sess_dev->rnbd_dev->ibd_bio_set, datalen, GFP_KERNEL); 149 if (IS_ERR(bio)) { 150 err = PTR_ERR(bio); 151 rnbd_srv_err(sess_dev, "Failed to generate bio, err: %d\n", err); 152 goto sess_dev_put; 153 } 154 155 io = container_of(bio, struct rnbd_dev_blk_io, bio); 156 io->dev = sess_dev->rnbd_dev; 157 io->priv = priv; 158 159 bio->bi_end_io = rnbd_dev_bi_end_io; 160 bio->bi_private = io; 161 bio->bi_opf = rnbd_to_bio_flags(le32_to_cpu(msg->rw)); 162 bio->bi_iter.bi_sector = le64_to_cpu(msg->sector); 163 bio->bi_iter.bi_size = le32_to_cpu(msg->bi_size); 164 prio = srv_sess->ver < RNBD_PROTO_VER_MAJOR || 165 usrlen < sizeof(*msg) ? 0 : le16_to_cpu(msg->prio); 166 bio_set_prio(bio, prio); 167 bio_set_dev(bio, sess_dev->rnbd_dev->bdev); 168 169 submit_bio(bio); 170 171 return 0; 172 173 sess_dev_put: 174 rnbd_put_sess_dev(sess_dev); 175 err: 176 kfree(priv); 177 return err; 178 } 179 180 static void destroy_device(struct kref *kref) 181 { 182 struct rnbd_srv_dev *dev = container_of(kref, struct rnbd_srv_dev, kref); 183 184 WARN_ONCE(!list_empty(&dev->sess_dev_list), 185 "Device %s is being destroyed but still in use!\n", 186 dev->id); 187 188 spin_lock(&dev_lock); 189 list_del(&dev->list); 190 spin_unlock(&dev_lock); 191 192 mutex_destroy(&dev->lock); 193 if (dev->dev_kobj.state_in_sysfs) 194 /* 195 * Destroy kobj only if it was really created. 196 */ 197 rnbd_srv_destroy_dev_sysfs(dev); 198 else 199 kfree(dev); 200 } 201 202 static void rnbd_put_srv_dev(struct rnbd_srv_dev *dev) 203 { 204 kref_put(&dev->kref, destroy_device); 205 } 206 207 void rnbd_destroy_sess_dev(struct rnbd_srv_sess_dev *sess_dev, bool keep_id) 208 { 209 DECLARE_COMPLETION_ONSTACK(dc); 210 211 if (keep_id) 212 /* free the resources for the id but don't */ 213 /* allow to re-use the id itself because it */ 214 /* is still used by the client */ 215 xa_cmpxchg(&sess_dev->sess->index_idr, sess_dev->device_id, 216 sess_dev, NULL, 0); 217 else 218 xa_erase(&sess_dev->sess->index_idr, sess_dev->device_id); 219 synchronize_rcu(); 220 221 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 } 238 239 static 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); 251 252 out: 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 } 265 266 static int create_sess(struct rtrs_srv_sess *rtrs) 267 { 268 struct rnbd_srv_session *srv_sess; 269 char pathname[NAME_MAX]; 270 int err; 271 272 err = rtrs_srv_get_path_name(rtrs, pathname, sizeof(pathname)); 273 if (err) { 274 pr_err("rtrs_srv_get_path_name(%s): %d\n", pathname, 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 path %s failed\n", 288 pathname); 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 strscpy(srv_sess->sessname, pathname, sizeof(srv_sess->sessname)); 302 303 rtrs_srv_set_sess_priv(rtrs, srv_sess); 304 305 return 0; 306 } 307 308 static int rnbd_srv_link_ev(struct rtrs_srv_sess *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 } 330 331 void rnbd_srv_sess_dev_force_close(struct rnbd_srv_sess_dev *sess_dev, 332 struct kobj_attribute *attr) 333 { 334 struct rnbd_srv_session *sess = sess_dev->sess; 335 336 sess_dev->keep_id = true; 337 /* It is already started to close by client's close message. */ 338 if (!mutex_trylock(&sess->lock)) 339 return; 340 /* first remove sysfs itself to avoid deadlock */ 341 sysfs_remove_file_self(&sess_dev->kobj, &attr->attr); 342 rnbd_srv_destroy_dev_session_sysfs(sess_dev); 343 mutex_unlock(&sess->lock); 344 } 345 346 static int process_msg_close(struct rnbd_srv_session *srv_sess, 347 void *data, size_t datalen, const void *usr, 348 size_t usrlen) 349 { 350 const struct rnbd_msg_close *close_msg = usr; 351 struct rnbd_srv_sess_dev *sess_dev; 352 353 sess_dev = rnbd_get_sess_dev(le32_to_cpu(close_msg->device_id), 354 srv_sess); 355 if (IS_ERR(sess_dev)) 356 return 0; 357 358 rnbd_put_sess_dev(sess_dev); 359 mutex_lock(&srv_sess->lock); 360 rnbd_srv_destroy_dev_session_sysfs(sess_dev); 361 mutex_unlock(&srv_sess->lock); 362 return 0; 363 } 364 365 static int process_msg_open(struct rnbd_srv_session *srv_sess, 366 const void *msg, size_t len, 367 void *data, size_t datalen); 368 369 static int process_msg_sess_info(struct rnbd_srv_session *srv_sess, 370 const void *msg, size_t len, 371 void *data, size_t datalen); 372 373 static int rnbd_srv_rdma_ev(void *priv, 374 struct rtrs_srv_op *id, int dir, 375 void *data, size_t datalen, const void *usr, 376 size_t usrlen) 377 { 378 struct rnbd_srv_session *srv_sess = priv; 379 const struct rnbd_msg_hdr *hdr = usr; 380 int ret = 0; 381 u16 type; 382 383 if (WARN_ON_ONCE(!srv_sess)) 384 return -ENODEV; 385 386 type = le16_to_cpu(hdr->type); 387 388 switch (type) { 389 case RNBD_MSG_IO: 390 return process_rdma(srv_sess, id, data, datalen, usr, usrlen); 391 case RNBD_MSG_CLOSE: 392 ret = process_msg_close(srv_sess, data, datalen, usr, usrlen); 393 break; 394 case RNBD_MSG_OPEN: 395 ret = process_msg_open(srv_sess, usr, usrlen, data, datalen); 396 break; 397 case RNBD_MSG_SESS_INFO: 398 ret = process_msg_sess_info(srv_sess, usr, usrlen, data, 399 datalen); 400 break; 401 default: 402 pr_warn("Received unexpected message type %d with dir %d from session %s\n", 403 type, dir, srv_sess->sessname); 404 return -EINVAL; 405 } 406 407 rtrs_srv_resp_rdma(id, ret); 408 return 0; 409 } 410 411 static struct rnbd_srv_sess_dev 412 *rnbd_sess_dev_alloc(struct rnbd_srv_session *srv_sess) 413 { 414 struct rnbd_srv_sess_dev *sess_dev; 415 int error; 416 417 sess_dev = kzalloc(sizeof(*sess_dev), GFP_KERNEL); 418 if (!sess_dev) 419 return ERR_PTR(-ENOMEM); 420 421 error = xa_alloc(&srv_sess->index_idr, &sess_dev->device_id, sess_dev, 422 xa_limit_32b, GFP_NOWAIT); 423 if (error < 0) { 424 pr_warn("Allocating idr failed, err: %d\n", error); 425 kfree(sess_dev); 426 return ERR_PTR(error); 427 } 428 429 return sess_dev; 430 } 431 432 static struct rnbd_srv_dev *rnbd_srv_init_srv_dev(const char *id) 433 { 434 struct rnbd_srv_dev *dev; 435 436 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 437 if (!dev) 438 return ERR_PTR(-ENOMEM); 439 440 strscpy(dev->id, id, sizeof(dev->id)); 441 kref_init(&dev->kref); 442 INIT_LIST_HEAD(&dev->sess_dev_list); 443 mutex_init(&dev->lock); 444 445 return dev; 446 } 447 448 static struct rnbd_srv_dev * 449 rnbd_srv_find_or_add_srv_dev(struct rnbd_srv_dev *new_dev) 450 { 451 struct rnbd_srv_dev *dev; 452 453 spin_lock(&dev_lock); 454 list_for_each_entry(dev, &dev_list, list) { 455 if (!strncmp(dev->id, new_dev->id, sizeof(dev->id))) { 456 if (!kref_get_unless_zero(&dev->kref)) 457 /* 458 * We lost the race, device is almost dead. 459 * Continue traversing to find a valid one. 460 */ 461 continue; 462 spin_unlock(&dev_lock); 463 return dev; 464 } 465 } 466 list_add(&new_dev->list, &dev_list); 467 spin_unlock(&dev_lock); 468 469 return new_dev; 470 } 471 472 static int rnbd_srv_check_update_open_perm(struct rnbd_srv_dev *srv_dev, 473 struct rnbd_srv_session *srv_sess, 474 enum rnbd_access_mode access_mode) 475 { 476 int ret = -EPERM; 477 478 mutex_lock(&srv_dev->lock); 479 480 switch (access_mode) { 481 case RNBD_ACCESS_RO: 482 ret = 0; 483 break; 484 case RNBD_ACCESS_RW: 485 if (srv_dev->open_write_cnt == 0) { 486 srv_dev->open_write_cnt++; 487 ret = 0; 488 } else { 489 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", 490 srv_dev->id, srv_sess->sessname, 491 srv_dev->open_write_cnt, 492 rnbd_access_mode_str(access_mode)); 493 } 494 break; 495 case RNBD_ACCESS_MIGRATION: 496 if (srv_dev->open_write_cnt < 2) { 497 srv_dev->open_write_cnt++; 498 ret = 0; 499 } else { 500 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", 501 srv_dev->id, srv_sess->sessname, 502 srv_dev->open_write_cnt, 503 rnbd_access_mode_str(access_mode)); 504 } 505 break; 506 default: 507 pr_err("Received mapping request for device '%s' on session %s with invalid access mode: %d\n", 508 srv_dev->id, srv_sess->sessname, access_mode); 509 ret = -EINVAL; 510 } 511 512 mutex_unlock(&srv_dev->lock); 513 514 return ret; 515 } 516 517 static struct rnbd_srv_dev * 518 rnbd_srv_get_or_create_srv_dev(struct rnbd_dev *rnbd_dev, 519 struct rnbd_srv_session *srv_sess, 520 enum rnbd_access_mode access_mode) 521 { 522 int ret; 523 struct rnbd_srv_dev *new_dev, *dev; 524 525 new_dev = rnbd_srv_init_srv_dev(rnbd_dev->name); 526 if (IS_ERR(new_dev)) 527 return new_dev; 528 529 dev = rnbd_srv_find_or_add_srv_dev(new_dev); 530 if (dev != new_dev) 531 kfree(new_dev); 532 533 ret = rnbd_srv_check_update_open_perm(dev, srv_sess, access_mode); 534 if (ret) { 535 rnbd_put_srv_dev(dev); 536 return ERR_PTR(ret); 537 } 538 539 return dev; 540 } 541 542 static void rnbd_srv_fill_msg_open_rsp(struct rnbd_msg_open_rsp *rsp, 543 struct rnbd_srv_sess_dev *sess_dev) 544 { 545 struct rnbd_dev *rnbd_dev = sess_dev->rnbd_dev; 546 struct request_queue *q = bdev_get_queue(rnbd_dev->bdev); 547 548 rsp->hdr.type = cpu_to_le16(RNBD_MSG_OPEN_RSP); 549 rsp->device_id = 550 cpu_to_le32(sess_dev->device_id); 551 rsp->nsectors = 552 cpu_to_le64(get_capacity(rnbd_dev->bdev->bd_disk)); 553 rsp->logical_block_size = 554 cpu_to_le16(bdev_logical_block_size(rnbd_dev->bdev)); 555 rsp->physical_block_size = 556 cpu_to_le16(bdev_physical_block_size(rnbd_dev->bdev)); 557 rsp->max_segments = 558 cpu_to_le16(rnbd_dev_get_max_segs(rnbd_dev)); 559 rsp->max_hw_sectors = 560 cpu_to_le32(rnbd_dev_get_max_hw_sects(rnbd_dev)); 561 rsp->max_write_same_sectors = 562 cpu_to_le32(bdev_write_same(rnbd_dev->bdev)); 563 rsp->max_discard_sectors = 564 cpu_to_le32(rnbd_dev_get_max_discard_sects(rnbd_dev)); 565 rsp->discard_granularity = 566 cpu_to_le32(rnbd_dev_get_discard_granularity(rnbd_dev)); 567 rsp->discard_alignment = 568 cpu_to_le32(rnbd_dev_get_discard_alignment(rnbd_dev)); 569 rsp->secure_discard = 570 cpu_to_le16(rnbd_dev_get_secure_discard(rnbd_dev)); 571 rsp->rotational = !blk_queue_nonrot(q); 572 rsp->cache_policy = 0; 573 if (test_bit(QUEUE_FLAG_WC, &q->queue_flags)) 574 rsp->cache_policy |= RNBD_WRITEBACK; 575 if (blk_queue_fua(q)) 576 rsp->cache_policy |= RNBD_FUA; 577 } 578 579 static struct rnbd_srv_sess_dev * 580 rnbd_srv_create_set_sess_dev(struct rnbd_srv_session *srv_sess, 581 const struct rnbd_msg_open *open_msg, 582 struct rnbd_dev *rnbd_dev, fmode_t open_flags, 583 struct rnbd_srv_dev *srv_dev) 584 { 585 struct rnbd_srv_sess_dev *sdev = rnbd_sess_dev_alloc(srv_sess); 586 587 if (IS_ERR(sdev)) 588 return sdev; 589 590 kref_init(&sdev->kref); 591 592 strscpy(sdev->pathname, open_msg->dev_name, sizeof(sdev->pathname)); 593 594 sdev->rnbd_dev = rnbd_dev; 595 sdev->sess = srv_sess; 596 sdev->dev = srv_dev; 597 sdev->open_flags = open_flags; 598 sdev->access_mode = open_msg->access_mode; 599 600 return sdev; 601 } 602 603 static char *rnbd_srv_get_full_path(struct rnbd_srv_session *srv_sess, 604 const char *dev_name) 605 { 606 char *full_path; 607 char *a, *b; 608 609 full_path = kmalloc(PATH_MAX, GFP_KERNEL); 610 if (!full_path) 611 return ERR_PTR(-ENOMEM); 612 613 /* 614 * Replace %SESSNAME% with a real session name in order to 615 * create device namespace. 616 */ 617 a = strnstr(dev_search_path, "%SESSNAME%", sizeof(dev_search_path)); 618 if (a) { 619 int len = a - dev_search_path; 620 621 len = snprintf(full_path, PATH_MAX, "%.*s/%s/%s", len, 622 dev_search_path, srv_sess->sessname, dev_name); 623 if (len >= PATH_MAX) { 624 pr_err("Too long path: %s, %s, %s\n", 625 dev_search_path, srv_sess->sessname, dev_name); 626 kfree(full_path); 627 return ERR_PTR(-EINVAL); 628 } 629 } else { 630 snprintf(full_path, PATH_MAX, "%s/%s", 631 dev_search_path, dev_name); 632 } 633 634 /* eliminitate duplicated slashes */ 635 a = strchr(full_path, '/'); 636 b = a; 637 while (*b != '\0') { 638 if (*b == '/' && *a == '/') { 639 b++; 640 } else { 641 a++; 642 *a = *b; 643 b++; 644 } 645 } 646 a++; 647 *a = '\0'; 648 649 return full_path; 650 } 651 652 static int process_msg_sess_info(struct rnbd_srv_session *srv_sess, 653 const void *msg, size_t len, 654 void *data, size_t datalen) 655 { 656 const struct rnbd_msg_sess_info *sess_info_msg = msg; 657 struct rnbd_msg_sess_info_rsp *rsp = data; 658 659 srv_sess->ver = min_t(u8, sess_info_msg->ver, RNBD_PROTO_VER_MAJOR); 660 pr_debug("Session %s using protocol version %d (client version: %d, server version: %d)\n", 661 srv_sess->sessname, srv_sess->ver, 662 sess_info_msg->ver, RNBD_PROTO_VER_MAJOR); 663 664 rsp->hdr.type = cpu_to_le16(RNBD_MSG_SESS_INFO_RSP); 665 rsp->ver = srv_sess->ver; 666 667 return 0; 668 } 669 670 /** 671 * find_srv_sess_dev() - a dev is already opened by this name 672 * @srv_sess: the session to search. 673 * @dev_name: string containing the name of the device. 674 * 675 * Return struct rnbd_srv_sess_dev if srv_sess already opened the dev_name 676 * NULL if the session didn't open the device yet. 677 */ 678 static struct rnbd_srv_sess_dev * 679 find_srv_sess_dev(struct rnbd_srv_session *srv_sess, const char *dev_name) 680 { 681 struct rnbd_srv_sess_dev *sess_dev; 682 683 if (list_empty(&srv_sess->sess_dev_list)) 684 return NULL; 685 686 list_for_each_entry(sess_dev, &srv_sess->sess_dev_list, sess_list) 687 if (!strcmp(sess_dev->pathname, dev_name)) 688 return sess_dev; 689 690 return NULL; 691 } 692 693 static int process_msg_open(struct rnbd_srv_session *srv_sess, 694 const void *msg, size_t len, 695 void *data, size_t datalen) 696 { 697 int ret; 698 struct rnbd_srv_dev *srv_dev; 699 struct rnbd_srv_sess_dev *srv_sess_dev; 700 const struct rnbd_msg_open *open_msg = msg; 701 fmode_t open_flags; 702 char *full_path; 703 struct rnbd_dev *rnbd_dev; 704 struct rnbd_msg_open_rsp *rsp = data; 705 706 pr_debug("Open message received: session='%s' path='%s' access_mode=%d\n", 707 srv_sess->sessname, open_msg->dev_name, 708 open_msg->access_mode); 709 open_flags = FMODE_READ; 710 if (open_msg->access_mode != RNBD_ACCESS_RO) 711 open_flags |= FMODE_WRITE; 712 713 mutex_lock(&srv_sess->lock); 714 715 srv_sess_dev = find_srv_sess_dev(srv_sess, open_msg->dev_name); 716 if (srv_sess_dev) 717 goto fill_response; 718 719 if ((strlen(dev_search_path) + strlen(open_msg->dev_name)) 720 >= PATH_MAX) { 721 pr_err("Opening device for session %s failed, device path too long. '%s/%s' is longer than PATH_MAX (%d)\n", 722 srv_sess->sessname, dev_search_path, open_msg->dev_name, 723 PATH_MAX); 724 ret = -EINVAL; 725 goto reject; 726 } 727 if (strstr(open_msg->dev_name, "..")) { 728 pr_err("Opening device for session %s failed, device path %s contains relative path ..\n", 729 srv_sess->sessname, open_msg->dev_name); 730 ret = -EINVAL; 731 goto reject; 732 } 733 full_path = rnbd_srv_get_full_path(srv_sess, open_msg->dev_name); 734 if (IS_ERR(full_path)) { 735 ret = PTR_ERR(full_path); 736 pr_err("Opening device '%s' for client %s failed, failed to get device full path, err: %d\n", 737 open_msg->dev_name, srv_sess->sessname, ret); 738 goto reject; 739 } 740 741 rnbd_dev = rnbd_dev_open(full_path, open_flags, 742 &srv_sess->sess_bio_set); 743 if (IS_ERR(rnbd_dev)) { 744 pr_err("Opening device '%s' on session %s failed, failed to open the block device, err: %ld\n", 745 full_path, srv_sess->sessname, PTR_ERR(rnbd_dev)); 746 ret = PTR_ERR(rnbd_dev); 747 goto free_path; 748 } 749 750 srv_dev = rnbd_srv_get_or_create_srv_dev(rnbd_dev, srv_sess, 751 open_msg->access_mode); 752 if (IS_ERR(srv_dev)) { 753 pr_err("Opening device '%s' on session %s failed, creating srv_dev failed, err: %ld\n", 754 full_path, srv_sess->sessname, PTR_ERR(srv_dev)); 755 ret = PTR_ERR(srv_dev); 756 goto rnbd_dev_close; 757 } 758 759 srv_sess_dev = rnbd_srv_create_set_sess_dev(srv_sess, open_msg, 760 rnbd_dev, open_flags, 761 srv_dev); 762 if (IS_ERR(srv_sess_dev)) { 763 pr_err("Opening device '%s' on session %s failed, creating sess_dev failed, err: %ld\n", 764 full_path, srv_sess->sessname, PTR_ERR(srv_sess_dev)); 765 ret = PTR_ERR(srv_sess_dev); 766 goto srv_dev_put; 767 } 768 769 /* Create the srv_dev sysfs files if they haven't been created yet. The 770 * reason to delay the creation is not to create the sysfs files before 771 * we are sure the device can be opened. 772 */ 773 mutex_lock(&srv_dev->lock); 774 if (!srv_dev->dev_kobj.state_in_sysfs) { 775 ret = rnbd_srv_create_dev_sysfs(srv_dev, rnbd_dev->bdev, 776 rnbd_dev->name); 777 if (ret) { 778 mutex_unlock(&srv_dev->lock); 779 rnbd_srv_err(srv_sess_dev, 780 "Opening device failed, failed to create device sysfs files, err: %d\n", 781 ret); 782 goto free_srv_sess_dev; 783 } 784 } 785 786 ret = rnbd_srv_create_dev_session_sysfs(srv_sess_dev); 787 if (ret) { 788 mutex_unlock(&srv_dev->lock); 789 rnbd_srv_err(srv_sess_dev, 790 "Opening device failed, failed to create dev client sysfs files, err: %d\n", 791 ret); 792 goto free_srv_sess_dev; 793 } 794 795 list_add(&srv_sess_dev->dev_list, &srv_dev->sess_dev_list); 796 mutex_unlock(&srv_dev->lock); 797 798 list_add(&srv_sess_dev->sess_list, &srv_sess->sess_dev_list); 799 800 rnbd_srv_info(srv_sess_dev, "Opened device '%s'\n", srv_dev->id); 801 802 kfree(full_path); 803 804 fill_response: 805 rnbd_srv_fill_msg_open_rsp(rsp, srv_sess_dev); 806 mutex_unlock(&srv_sess->lock); 807 return 0; 808 809 free_srv_sess_dev: 810 xa_erase(&srv_sess->index_idr, srv_sess_dev->device_id); 811 synchronize_rcu(); 812 kfree(srv_sess_dev); 813 srv_dev_put: 814 if (open_msg->access_mode != RNBD_ACCESS_RO) { 815 mutex_lock(&srv_dev->lock); 816 srv_dev->open_write_cnt--; 817 mutex_unlock(&srv_dev->lock); 818 } 819 rnbd_put_srv_dev(srv_dev); 820 rnbd_dev_close: 821 rnbd_dev_close(rnbd_dev); 822 free_path: 823 kfree(full_path); 824 reject: 825 mutex_unlock(&srv_sess->lock); 826 return ret; 827 } 828 829 static struct rtrs_srv_ctx *rtrs_ctx; 830 831 static struct rtrs_srv_ops rtrs_ops; 832 static int __init rnbd_srv_init_module(void) 833 { 834 int err; 835 836 BUILD_BUG_ON(sizeof(struct rnbd_msg_hdr) != 4); 837 BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info) != 36); 838 BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info_rsp) != 36); 839 BUILD_BUG_ON(sizeof(struct rnbd_msg_open) != 264); 840 BUILD_BUG_ON(sizeof(struct rnbd_msg_close) != 8); 841 BUILD_BUG_ON(sizeof(struct rnbd_msg_open_rsp) != 56); 842 rtrs_ops = (struct rtrs_srv_ops) { 843 .rdma_ev = rnbd_srv_rdma_ev, 844 .link_ev = rnbd_srv_link_ev, 845 }; 846 rtrs_ctx = rtrs_srv_open(&rtrs_ops, port_nr); 847 if (IS_ERR(rtrs_ctx)) { 848 err = PTR_ERR(rtrs_ctx); 849 pr_err("rtrs_srv_open(), err: %d\n", err); 850 return err; 851 } 852 853 err = rnbd_srv_create_sysfs_files(); 854 if (err) { 855 pr_err("rnbd_srv_create_sysfs_files(), err: %d\n", err); 856 rtrs_srv_close(rtrs_ctx); 857 return err; 858 } 859 860 return 0; 861 } 862 863 static void __exit rnbd_srv_cleanup_module(void) 864 { 865 rtrs_srv_close(rtrs_ctx); 866 WARN_ON(!list_empty(&sess_list)); 867 rnbd_srv_destroy_sysfs_files(); 868 } 869 870 module_init(rnbd_srv_init_module); 871 module_exit(rnbd_srv_cleanup_module); 872