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 void rnbd_dev_bi_end_io(struct bio *bio) 118 { 119 rnbd_endio(bio->bi_private, blk_status_to_errno(bio->bi_status)); 120 bio_put(bio); 121 } 122 123 static int process_rdma(struct rnbd_srv_session *srv_sess, 124 struct rtrs_srv_op *id, void *data, u32 datalen, 125 const void *usr, size_t usrlen) 126 { 127 const struct rnbd_msg_io *msg = usr; 128 struct rnbd_io_private *priv; 129 struct rnbd_srv_sess_dev *sess_dev; 130 u32 dev_id; 131 int err; 132 struct bio *bio; 133 short prio; 134 135 priv = kmalloc(sizeof(*priv), GFP_KERNEL); 136 if (!priv) 137 return -ENOMEM; 138 139 dev_id = le32_to_cpu(msg->device_id); 140 141 sess_dev = rnbd_get_sess_dev(dev_id, srv_sess); 142 if (IS_ERR(sess_dev)) { 143 pr_err_ratelimited("Got I/O request on session %s for unknown device id %d\n", 144 srv_sess->sessname, dev_id); 145 err = -ENOTCONN; 146 goto err; 147 } 148 149 priv->sess_dev = sess_dev; 150 priv->id = id; 151 152 bio = bio_alloc(sess_dev->rnbd_dev->bdev, 1, 153 rnbd_to_bio_flags(le32_to_cpu(msg->rw)), GFP_KERNEL); 154 if (bio_add_page(bio, virt_to_page(data), datalen, 155 offset_in_page(data)) != datalen) { 156 rnbd_srv_err(sess_dev, "Failed to map data to bio\n"); 157 err = -EINVAL; 158 goto bio_put; 159 } 160 161 bio->bi_end_io = rnbd_dev_bi_end_io; 162 bio->bi_private = priv; 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); 168 169 submit_bio(bio); 170 171 return 0; 172 173 bio_put: 174 bio_put(bio); 175 rnbd_put_sess_dev(sess_dev); 176 err: 177 kfree(priv); 178 return err; 179 } 180 181 static void destroy_device(struct kref *kref) 182 { 183 struct rnbd_srv_dev *dev = container_of(kref, struct rnbd_srv_dev, kref); 184 185 WARN_ONCE(!list_empty(&dev->sess_dev_list), 186 "Device %s is being destroyed but still in use!\n", 187 dev->id); 188 189 spin_lock(&dev_lock); 190 list_del(&dev->list); 191 spin_unlock(&dev_lock); 192 193 mutex_destroy(&dev->lock); 194 if (dev->dev_kobj.state_in_sysfs) 195 /* 196 * Destroy kobj only if it was really created. 197 */ 198 rnbd_srv_destroy_dev_sysfs(dev); 199 else 200 kfree(dev); 201 } 202 203 static void rnbd_put_srv_dev(struct rnbd_srv_dev *dev) 204 { 205 kref_put(&dev->kref, destroy_device); 206 } 207 208 void rnbd_destroy_sess_dev(struct rnbd_srv_sess_dev *sess_dev, bool keep_id) 209 { 210 DECLARE_COMPLETION_ONSTACK(dc); 211 212 if (keep_id) 213 /* free the resources for the id but don't */ 214 /* allow to re-use the id itself because it */ 215 /* is still used by the client */ 216 xa_cmpxchg(&sess_dev->sess->index_idr, sess_dev->device_id, 217 sess_dev, NULL, 0); 218 else 219 xa_erase(&sess_dev->sess->index_idr, sess_dev->device_id); 220 synchronize_rcu(); 221 222 sess_dev->destroy_comp = &dc; 223 rnbd_put_sess_dev(sess_dev); 224 wait_for_completion(&dc); /* wait for inflights to drop to zero */ 225 226 rnbd_dev_close(sess_dev->rnbd_dev); 227 list_del(&sess_dev->sess_list); 228 mutex_lock(&sess_dev->dev->lock); 229 list_del(&sess_dev->dev_list); 230 if (sess_dev->open_flags & FMODE_WRITE) 231 sess_dev->dev->open_write_cnt--; 232 mutex_unlock(&sess_dev->dev->lock); 233 234 rnbd_put_srv_dev(sess_dev->dev); 235 236 rnbd_srv_info(sess_dev, "Device closed\n"); 237 kfree(sess_dev); 238 } 239 240 static void destroy_sess(struct rnbd_srv_session *srv_sess) 241 { 242 struct rnbd_srv_sess_dev *sess_dev, *tmp; 243 244 if (list_empty(&srv_sess->sess_dev_list)) 245 goto out; 246 247 mutex_lock(&srv_sess->lock); 248 list_for_each_entry_safe(sess_dev, tmp, &srv_sess->sess_dev_list, 249 sess_list) 250 rnbd_srv_destroy_dev_session_sysfs(sess_dev); 251 mutex_unlock(&srv_sess->lock); 252 253 out: 254 xa_destroy(&srv_sess->index_idr); 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 xa_init_flags(&srv_sess->index_idr, XA_FLAGS_ALLOC); 284 INIT_LIST_HEAD(&srv_sess->sess_dev_list); 285 mutex_init(&srv_sess->lock); 286 mutex_lock(&sess_lock); 287 list_add(&srv_sess->list, &sess_list); 288 mutex_unlock(&sess_lock); 289 290 srv_sess->rtrs = rtrs; 291 strscpy(srv_sess->sessname, pathname, sizeof(srv_sess->sessname)); 292 293 rtrs_srv_set_sess_priv(rtrs, srv_sess); 294 295 return 0; 296 } 297 298 static int rnbd_srv_link_ev(struct rtrs_srv_sess *rtrs, 299 enum rtrs_srv_link_ev ev, void *priv) 300 { 301 struct rnbd_srv_session *srv_sess = priv; 302 303 switch (ev) { 304 case RTRS_SRV_LINK_EV_CONNECTED: 305 return create_sess(rtrs); 306 307 case RTRS_SRV_LINK_EV_DISCONNECTED: 308 if (WARN_ON_ONCE(!srv_sess)) 309 return -EINVAL; 310 311 destroy_sess(srv_sess); 312 return 0; 313 314 default: 315 pr_warn("Received unknown RTRS session event %d from session %s\n", 316 ev, srv_sess->sessname); 317 return -EINVAL; 318 } 319 } 320 321 void rnbd_srv_sess_dev_force_close(struct rnbd_srv_sess_dev *sess_dev, 322 struct kobj_attribute *attr) 323 { 324 struct rnbd_srv_session *sess = sess_dev->sess; 325 326 sess_dev->keep_id = true; 327 /* It is already started to close by client's close message. */ 328 if (!mutex_trylock(&sess->lock)) 329 return; 330 /* first remove sysfs itself to avoid deadlock */ 331 sysfs_remove_file_self(&sess_dev->kobj, &attr->attr); 332 rnbd_srv_destroy_dev_session_sysfs(sess_dev); 333 mutex_unlock(&sess->lock); 334 } 335 336 static int process_msg_close(struct rnbd_srv_session *srv_sess, 337 void *data, size_t datalen, const void *usr, 338 size_t usrlen) 339 { 340 const struct rnbd_msg_close *close_msg = usr; 341 struct rnbd_srv_sess_dev *sess_dev; 342 343 sess_dev = rnbd_get_sess_dev(le32_to_cpu(close_msg->device_id), 344 srv_sess); 345 if (IS_ERR(sess_dev)) 346 return 0; 347 348 rnbd_put_sess_dev(sess_dev); 349 mutex_lock(&srv_sess->lock); 350 rnbd_srv_destroy_dev_session_sysfs(sess_dev); 351 mutex_unlock(&srv_sess->lock); 352 return 0; 353 } 354 355 static int process_msg_open(struct rnbd_srv_session *srv_sess, 356 const void *msg, size_t len, 357 void *data, size_t datalen); 358 359 static int process_msg_sess_info(struct rnbd_srv_session *srv_sess, 360 const void *msg, size_t len, 361 void *data, size_t datalen); 362 363 static int rnbd_srv_rdma_ev(void *priv, 364 struct rtrs_srv_op *id, int dir, 365 void *data, size_t datalen, const void *usr, 366 size_t usrlen) 367 { 368 struct rnbd_srv_session *srv_sess = priv; 369 const struct rnbd_msg_hdr *hdr = usr; 370 int ret = 0; 371 u16 type; 372 373 if (WARN_ON_ONCE(!srv_sess)) 374 return -ENODEV; 375 376 type = le16_to_cpu(hdr->type); 377 378 switch (type) { 379 case RNBD_MSG_IO: 380 return process_rdma(srv_sess, id, data, datalen, usr, usrlen); 381 case RNBD_MSG_CLOSE: 382 ret = process_msg_close(srv_sess, data, datalen, usr, usrlen); 383 break; 384 case RNBD_MSG_OPEN: 385 ret = process_msg_open(srv_sess, usr, usrlen, data, datalen); 386 break; 387 case RNBD_MSG_SESS_INFO: 388 ret = process_msg_sess_info(srv_sess, usr, usrlen, data, 389 datalen); 390 break; 391 default: 392 pr_warn("Received unexpected message type %d with dir %d from session %s\n", 393 type, dir, srv_sess->sessname); 394 return -EINVAL; 395 } 396 397 rtrs_srv_resp_rdma(id, ret); 398 return 0; 399 } 400 401 static struct rnbd_srv_sess_dev 402 *rnbd_sess_dev_alloc(struct rnbd_srv_session *srv_sess) 403 { 404 struct rnbd_srv_sess_dev *sess_dev; 405 int error; 406 407 sess_dev = kzalloc(sizeof(*sess_dev), GFP_KERNEL); 408 if (!sess_dev) 409 return ERR_PTR(-ENOMEM); 410 411 error = xa_alloc(&srv_sess->index_idr, &sess_dev->device_id, sess_dev, 412 xa_limit_32b, GFP_NOWAIT); 413 if (error < 0) { 414 pr_warn("Allocating idr failed, err: %d\n", error); 415 kfree(sess_dev); 416 return ERR_PTR(error); 417 } 418 419 return sess_dev; 420 } 421 422 static struct rnbd_srv_dev *rnbd_srv_init_srv_dev(const char *id) 423 { 424 struct rnbd_srv_dev *dev; 425 426 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 427 if (!dev) 428 return ERR_PTR(-ENOMEM); 429 430 strscpy(dev->id, id, sizeof(dev->id)); 431 kref_init(&dev->kref); 432 INIT_LIST_HEAD(&dev->sess_dev_list); 433 mutex_init(&dev->lock); 434 435 return dev; 436 } 437 438 static struct rnbd_srv_dev * 439 rnbd_srv_find_or_add_srv_dev(struct rnbd_srv_dev *new_dev) 440 { 441 struct rnbd_srv_dev *dev; 442 443 spin_lock(&dev_lock); 444 list_for_each_entry(dev, &dev_list, list) { 445 if (!strncmp(dev->id, new_dev->id, sizeof(dev->id))) { 446 if (!kref_get_unless_zero(&dev->kref)) 447 /* 448 * We lost the race, device is almost dead. 449 * Continue traversing to find a valid one. 450 */ 451 continue; 452 spin_unlock(&dev_lock); 453 return dev; 454 } 455 } 456 list_add(&new_dev->list, &dev_list); 457 spin_unlock(&dev_lock); 458 459 return new_dev; 460 } 461 462 static int rnbd_srv_check_update_open_perm(struct rnbd_srv_dev *srv_dev, 463 struct rnbd_srv_session *srv_sess, 464 enum rnbd_access_mode access_mode) 465 { 466 int ret = -EPERM; 467 468 mutex_lock(&srv_dev->lock); 469 470 switch (access_mode) { 471 case RNBD_ACCESS_RO: 472 ret = 0; 473 break; 474 case RNBD_ACCESS_RW: 475 if (srv_dev->open_write_cnt == 0) { 476 srv_dev->open_write_cnt++; 477 ret = 0; 478 } else { 479 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", 480 srv_dev->id, srv_sess->sessname, 481 srv_dev->open_write_cnt, 482 rnbd_access_mode_str(access_mode)); 483 } 484 break; 485 case RNBD_ACCESS_MIGRATION: 486 if (srv_dev->open_write_cnt < 2) { 487 srv_dev->open_write_cnt++; 488 ret = 0; 489 } else { 490 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", 491 srv_dev->id, srv_sess->sessname, 492 srv_dev->open_write_cnt, 493 rnbd_access_mode_str(access_mode)); 494 } 495 break; 496 default: 497 pr_err("Received mapping request for device '%s' on session %s with invalid access mode: %d\n", 498 srv_dev->id, srv_sess->sessname, access_mode); 499 ret = -EINVAL; 500 } 501 502 mutex_unlock(&srv_dev->lock); 503 504 return ret; 505 } 506 507 static struct rnbd_srv_dev * 508 rnbd_srv_get_or_create_srv_dev(struct rnbd_dev *rnbd_dev, 509 struct rnbd_srv_session *srv_sess, 510 enum rnbd_access_mode access_mode) 511 { 512 int ret; 513 struct rnbd_srv_dev *new_dev, *dev; 514 515 new_dev = rnbd_srv_init_srv_dev(rnbd_dev->name); 516 if (IS_ERR(new_dev)) 517 return new_dev; 518 519 dev = rnbd_srv_find_or_add_srv_dev(new_dev); 520 if (dev != new_dev) 521 kfree(new_dev); 522 523 ret = rnbd_srv_check_update_open_perm(dev, srv_sess, access_mode); 524 if (ret) { 525 rnbd_put_srv_dev(dev); 526 return ERR_PTR(ret); 527 } 528 529 return dev; 530 } 531 532 static void rnbd_srv_fill_msg_open_rsp(struct rnbd_msg_open_rsp *rsp, 533 struct rnbd_srv_sess_dev *sess_dev) 534 { 535 struct rnbd_dev *rnbd_dev = sess_dev->rnbd_dev; 536 537 rsp->hdr.type = cpu_to_le16(RNBD_MSG_OPEN_RSP); 538 rsp->device_id = 539 cpu_to_le32(sess_dev->device_id); 540 rsp->nsectors = 541 cpu_to_le64(get_capacity(rnbd_dev->bdev->bd_disk)); 542 rsp->logical_block_size = 543 cpu_to_le16(bdev_logical_block_size(rnbd_dev->bdev)); 544 rsp->physical_block_size = 545 cpu_to_le16(bdev_physical_block_size(rnbd_dev->bdev)); 546 rsp->max_segments = 547 cpu_to_le16(rnbd_dev_get_max_segs(rnbd_dev)); 548 rsp->max_hw_sectors = 549 cpu_to_le32(rnbd_dev_get_max_hw_sects(rnbd_dev)); 550 rsp->max_write_same_sectors = 0; 551 rsp->max_discard_sectors = 552 cpu_to_le32(rnbd_dev_get_max_discard_sects(rnbd_dev)); 553 rsp->discard_granularity = 554 cpu_to_le32(rnbd_dev_get_discard_granularity(rnbd_dev)); 555 rsp->discard_alignment = 556 cpu_to_le32(rnbd_dev_get_discard_alignment(rnbd_dev)); 557 rsp->secure_discard = 558 cpu_to_le16(rnbd_dev_get_secure_discard(rnbd_dev)); 559 rsp->cache_policy = 0; 560 if (bdev_write_cache(rnbd_dev->bdev)) 561 rsp->cache_policy |= RNBD_WRITEBACK; 562 if (bdev_fua(rnbd_dev->bdev)) 563 rsp->cache_policy |= RNBD_FUA; 564 } 565 566 static struct rnbd_srv_sess_dev * 567 rnbd_srv_create_set_sess_dev(struct rnbd_srv_session *srv_sess, 568 const struct rnbd_msg_open *open_msg, 569 struct rnbd_dev *rnbd_dev, fmode_t open_flags, 570 struct rnbd_srv_dev *srv_dev) 571 { 572 struct rnbd_srv_sess_dev *sdev = rnbd_sess_dev_alloc(srv_sess); 573 574 if (IS_ERR(sdev)) 575 return sdev; 576 577 kref_init(&sdev->kref); 578 579 strscpy(sdev->pathname, open_msg->dev_name, sizeof(sdev->pathname)); 580 581 sdev->rnbd_dev = rnbd_dev; 582 sdev->sess = srv_sess; 583 sdev->dev = srv_dev; 584 sdev->open_flags = open_flags; 585 sdev->access_mode = open_msg->access_mode; 586 587 return sdev; 588 } 589 590 static char *rnbd_srv_get_full_path(struct rnbd_srv_session *srv_sess, 591 const char *dev_name) 592 { 593 char *full_path; 594 char *a, *b; 595 596 full_path = kmalloc(PATH_MAX, GFP_KERNEL); 597 if (!full_path) 598 return ERR_PTR(-ENOMEM); 599 600 /* 601 * Replace %SESSNAME% with a real session name in order to 602 * create device namespace. 603 */ 604 a = strnstr(dev_search_path, "%SESSNAME%", sizeof(dev_search_path)); 605 if (a) { 606 int len = a - dev_search_path; 607 608 len = snprintf(full_path, PATH_MAX, "%.*s/%s/%s", len, 609 dev_search_path, srv_sess->sessname, dev_name); 610 if (len >= PATH_MAX) { 611 pr_err("Too long path: %s, %s, %s\n", 612 dev_search_path, srv_sess->sessname, dev_name); 613 kfree(full_path); 614 return ERR_PTR(-EINVAL); 615 } 616 } else { 617 snprintf(full_path, PATH_MAX, "%s/%s", 618 dev_search_path, dev_name); 619 } 620 621 /* eliminitate duplicated slashes */ 622 a = strchr(full_path, '/'); 623 b = a; 624 while (*b != '\0') { 625 if (*b == '/' && *a == '/') { 626 b++; 627 } else { 628 a++; 629 *a = *b; 630 b++; 631 } 632 } 633 a++; 634 *a = '\0'; 635 636 return full_path; 637 } 638 639 static int process_msg_sess_info(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 */ 665 static struct rnbd_srv_sess_dev * 666 find_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 } 679 680 static int process_msg_open(struct rnbd_srv_session *srv_sess, 681 const void *msg, size_t len, 682 void *data, size_t datalen) 683 { 684 int ret; 685 struct rnbd_srv_dev *srv_dev; 686 struct rnbd_srv_sess_dev *srv_sess_dev; 687 const struct rnbd_msg_open *open_msg = msg; 688 fmode_t open_flags; 689 char *full_path; 690 struct rnbd_dev *rnbd_dev; 691 struct rnbd_msg_open_rsp *rsp = data; 692 693 pr_debug("Open message received: session='%s' path='%s' access_mode=%d\n", 694 srv_sess->sessname, open_msg->dev_name, 695 open_msg->access_mode); 696 open_flags = FMODE_READ; 697 if (open_msg->access_mode != RNBD_ACCESS_RO) 698 open_flags |= FMODE_WRITE; 699 700 mutex_lock(&srv_sess->lock); 701 702 srv_sess_dev = find_srv_sess_dev(srv_sess, open_msg->dev_name); 703 if (srv_sess_dev) 704 goto fill_response; 705 706 if ((strlen(dev_search_path) + strlen(open_msg->dev_name)) 707 >= PATH_MAX) { 708 pr_err("Opening device for session %s failed, device path too long. '%s/%s' is longer than PATH_MAX (%d)\n", 709 srv_sess->sessname, dev_search_path, open_msg->dev_name, 710 PATH_MAX); 711 ret = -EINVAL; 712 goto reject; 713 } 714 if (strstr(open_msg->dev_name, "..")) { 715 pr_err("Opening device for session %s failed, device path %s contains relative path ..\n", 716 srv_sess->sessname, open_msg->dev_name); 717 ret = -EINVAL; 718 goto reject; 719 } 720 full_path = rnbd_srv_get_full_path(srv_sess, open_msg->dev_name); 721 if (IS_ERR(full_path)) { 722 ret = PTR_ERR(full_path); 723 pr_err("Opening device '%s' for client %s failed, failed to get device full path, err: %d\n", 724 open_msg->dev_name, srv_sess->sessname, ret); 725 goto reject; 726 } 727 728 rnbd_dev = rnbd_dev_open(full_path, open_flags); 729 if (IS_ERR(rnbd_dev)) { 730 pr_err("Opening device '%s' on session %s failed, failed to open the block device, err: %ld\n", 731 full_path, srv_sess->sessname, PTR_ERR(rnbd_dev)); 732 ret = PTR_ERR(rnbd_dev); 733 goto free_path; 734 } 735 736 srv_dev = rnbd_srv_get_or_create_srv_dev(rnbd_dev, srv_sess, 737 open_msg->access_mode); 738 if (IS_ERR(srv_dev)) { 739 pr_err("Opening device '%s' on session %s failed, creating srv_dev failed, err: %ld\n", 740 full_path, srv_sess->sessname, PTR_ERR(srv_dev)); 741 ret = PTR_ERR(srv_dev); 742 goto rnbd_dev_close; 743 } 744 745 srv_sess_dev = rnbd_srv_create_set_sess_dev(srv_sess, open_msg, 746 rnbd_dev, open_flags, 747 srv_dev); 748 if (IS_ERR(srv_sess_dev)) { 749 pr_err("Opening device '%s' on session %s failed, creating sess_dev failed, err: %ld\n", 750 full_path, srv_sess->sessname, PTR_ERR(srv_sess_dev)); 751 ret = PTR_ERR(srv_sess_dev); 752 goto srv_dev_put; 753 } 754 755 /* Create the srv_dev sysfs files if they haven't been created yet. The 756 * reason to delay the creation is not to create the sysfs files before 757 * we are sure the device can be opened. 758 */ 759 mutex_lock(&srv_dev->lock); 760 if (!srv_dev->dev_kobj.state_in_sysfs) { 761 ret = rnbd_srv_create_dev_sysfs(srv_dev, rnbd_dev->bdev, 762 rnbd_dev->name); 763 if (ret) { 764 mutex_unlock(&srv_dev->lock); 765 rnbd_srv_err(srv_sess_dev, 766 "Opening device failed, failed to create device sysfs files, err: %d\n", 767 ret); 768 goto free_srv_sess_dev; 769 } 770 } 771 772 ret = rnbd_srv_create_dev_session_sysfs(srv_sess_dev); 773 if (ret) { 774 mutex_unlock(&srv_dev->lock); 775 rnbd_srv_err(srv_sess_dev, 776 "Opening device failed, failed to create dev client sysfs files, err: %d\n", 777 ret); 778 goto free_srv_sess_dev; 779 } 780 781 list_add(&srv_sess_dev->dev_list, &srv_dev->sess_dev_list); 782 mutex_unlock(&srv_dev->lock); 783 784 list_add(&srv_sess_dev->sess_list, &srv_sess->sess_dev_list); 785 786 rnbd_srv_info(srv_sess_dev, "Opened device '%s'\n", srv_dev->id); 787 788 kfree(full_path); 789 790 fill_response: 791 rnbd_srv_fill_msg_open_rsp(rsp, srv_sess_dev); 792 mutex_unlock(&srv_sess->lock); 793 return 0; 794 795 free_srv_sess_dev: 796 xa_erase(&srv_sess->index_idr, srv_sess_dev->device_id); 797 synchronize_rcu(); 798 kfree(srv_sess_dev); 799 srv_dev_put: 800 if (open_msg->access_mode != RNBD_ACCESS_RO) { 801 mutex_lock(&srv_dev->lock); 802 srv_dev->open_write_cnt--; 803 mutex_unlock(&srv_dev->lock); 804 } 805 rnbd_put_srv_dev(srv_dev); 806 rnbd_dev_close: 807 rnbd_dev_close(rnbd_dev); 808 free_path: 809 kfree(full_path); 810 reject: 811 mutex_unlock(&srv_sess->lock); 812 return ret; 813 } 814 815 static struct rtrs_srv_ctx *rtrs_ctx; 816 817 static struct rtrs_srv_ops rtrs_ops; 818 static int __init rnbd_srv_init_module(void) 819 { 820 int err; 821 822 BUILD_BUG_ON(sizeof(struct rnbd_msg_hdr) != 4); 823 BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info) != 36); 824 BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info_rsp) != 36); 825 BUILD_BUG_ON(sizeof(struct rnbd_msg_open) != 264); 826 BUILD_BUG_ON(sizeof(struct rnbd_msg_close) != 8); 827 BUILD_BUG_ON(sizeof(struct rnbd_msg_open_rsp) != 56); 828 rtrs_ops = (struct rtrs_srv_ops) { 829 .rdma_ev = rnbd_srv_rdma_ev, 830 .link_ev = rnbd_srv_link_ev, 831 }; 832 rtrs_ctx = rtrs_srv_open(&rtrs_ops, port_nr); 833 if (IS_ERR(rtrs_ctx)) { 834 err = PTR_ERR(rtrs_ctx); 835 pr_err("rtrs_srv_open(), err: %d\n", err); 836 return err; 837 } 838 839 err = rnbd_srv_create_sysfs_files(); 840 if (err) { 841 pr_err("rnbd_srv_create_sysfs_files(), err: %d\n", err); 842 rtrs_srv_close(rtrs_ctx); 843 return err; 844 } 845 846 return 0; 847 } 848 849 static void __exit rnbd_srv_cleanup_module(void) 850 { 851 rtrs_srv_close(rtrs_ctx); 852 WARN_ON(!list_empty(&sess_list)); 853 rnbd_srv_destroy_sysfs_files(); 854 } 855 856 module_init(rnbd_srv_init_module); 857 module_exit(rnbd_srv_cleanup_module); 858