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 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; 242 unsigned long index; 243 244 if (xa_empty(&srv_sess->index_idr)) 245 goto out; 246 247 mutex_lock(&srv_sess->lock); 248 xa_for_each(&srv_sess->index_idr, index, sess_dev) 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); 254 255 pr_info("RTRS Session %s disconnected\n", srv_sess->sessname); 256 257 mutex_lock(&sess_lock); 258 list_del(&srv_sess->list); 259 mutex_unlock(&sess_lock); 260 261 mutex_destroy(&srv_sess->lock); 262 kfree(srv_sess); 263 } 264 265 static int create_sess(struct rtrs_srv_sess *rtrs) 266 { 267 struct rnbd_srv_session *srv_sess; 268 char pathname[NAME_MAX]; 269 int err; 270 271 err = rtrs_srv_get_path_name(rtrs, pathname, sizeof(pathname)); 272 if (err) { 273 pr_err("rtrs_srv_get_path_name(%s): %d\n", pathname, err); 274 275 return err; 276 } 277 srv_sess = kzalloc(sizeof(*srv_sess), GFP_KERNEL); 278 if (!srv_sess) 279 return -ENOMEM; 280 281 srv_sess->queue_depth = rtrs_srv_get_queue_depth(rtrs); 282 xa_init_flags(&srv_sess->index_idr, XA_FLAGS_ALLOC); 283 mutex_init(&srv_sess->lock); 284 mutex_lock(&sess_lock); 285 list_add(&srv_sess->list, &sess_list); 286 mutex_unlock(&sess_lock); 287 288 srv_sess->rtrs = rtrs; 289 strscpy(srv_sess->sessname, pathname, sizeof(srv_sess->sessname)); 290 291 rtrs_srv_set_sess_priv(rtrs, srv_sess); 292 293 return 0; 294 } 295 296 static int rnbd_srv_link_ev(struct rtrs_srv_sess *rtrs, 297 enum rtrs_srv_link_ev ev, void *priv) 298 { 299 struct rnbd_srv_session *srv_sess = priv; 300 301 switch (ev) { 302 case RTRS_SRV_LINK_EV_CONNECTED: 303 return create_sess(rtrs); 304 305 case RTRS_SRV_LINK_EV_DISCONNECTED: 306 if (WARN_ON_ONCE(!srv_sess)) 307 return -EINVAL; 308 309 destroy_sess(srv_sess); 310 return 0; 311 312 default: 313 pr_warn("Received unknown RTRS session event %d from session %s\n", 314 ev, srv_sess->sessname); 315 return -EINVAL; 316 } 317 } 318 319 void rnbd_srv_sess_dev_force_close(struct rnbd_srv_sess_dev *sess_dev, 320 struct kobj_attribute *attr) 321 { 322 struct rnbd_srv_session *sess = sess_dev->sess; 323 324 /* It is already started to close by client's close message. */ 325 if (!mutex_trylock(&sess->lock)) 326 return; 327 328 sess_dev->keep_id = true; 329 /* first remove sysfs itself to avoid deadlock */ 330 sysfs_remove_file_self(&sess_dev->kobj, &attr->attr); 331 rnbd_srv_destroy_dev_session_sysfs(sess_dev); 332 mutex_unlock(&sess->lock); 333 } 334 335 static int process_msg_close(struct rnbd_srv_session *srv_sess, 336 void *data, size_t datalen, const void *usr, 337 size_t usrlen) 338 { 339 const struct rnbd_msg_close *close_msg = usr; 340 struct rnbd_srv_sess_dev *sess_dev; 341 342 sess_dev = rnbd_get_sess_dev(le32_to_cpu(close_msg->device_id), 343 srv_sess); 344 if (IS_ERR(sess_dev)) 345 return 0; 346 347 rnbd_put_sess_dev(sess_dev); 348 mutex_lock(&srv_sess->lock); 349 rnbd_srv_destroy_dev_session_sysfs(sess_dev); 350 mutex_unlock(&srv_sess->lock); 351 return 0; 352 } 353 354 static int process_msg_open(struct rnbd_srv_session *srv_sess, 355 const void *msg, size_t len, 356 void *data, size_t datalen); 357 358 static int process_msg_sess_info(struct rnbd_srv_session *srv_sess, 359 const void *msg, size_t len, 360 void *data, size_t datalen); 361 362 static int rnbd_srv_rdma_ev(void *priv, 363 struct rtrs_srv_op *id, int dir, 364 void *data, size_t datalen, const void *usr, 365 size_t usrlen) 366 { 367 struct rnbd_srv_session *srv_sess = priv; 368 const struct rnbd_msg_hdr *hdr = usr; 369 int ret = 0; 370 u16 type; 371 372 if (WARN_ON_ONCE(!srv_sess)) 373 return -ENODEV; 374 375 type = le16_to_cpu(hdr->type); 376 377 switch (type) { 378 case RNBD_MSG_IO: 379 return process_rdma(srv_sess, id, data, datalen, usr, usrlen); 380 case RNBD_MSG_CLOSE: 381 ret = process_msg_close(srv_sess, data, datalen, usr, usrlen); 382 break; 383 case RNBD_MSG_OPEN: 384 ret = process_msg_open(srv_sess, usr, usrlen, data, datalen); 385 break; 386 case RNBD_MSG_SESS_INFO: 387 ret = process_msg_sess_info(srv_sess, usr, usrlen, data, 388 datalen); 389 break; 390 default: 391 pr_warn("Received unexpected message type %d with dir %d from session %s\n", 392 type, dir, srv_sess->sessname); 393 return -EINVAL; 394 } 395 396 rtrs_srv_resp_rdma(id, ret); 397 return 0; 398 } 399 400 static struct rnbd_srv_sess_dev 401 *rnbd_sess_dev_alloc(struct rnbd_srv_session *srv_sess) 402 { 403 struct rnbd_srv_sess_dev *sess_dev; 404 int error; 405 406 sess_dev = kzalloc(sizeof(*sess_dev), GFP_KERNEL); 407 if (!sess_dev) 408 return ERR_PTR(-ENOMEM); 409 410 error = xa_alloc(&srv_sess->index_idr, &sess_dev->device_id, sess_dev, 411 xa_limit_32b, GFP_NOWAIT); 412 if (error < 0) { 413 pr_warn("Allocating idr failed, err: %d\n", error); 414 kfree(sess_dev); 415 return ERR_PTR(error); 416 } 417 418 return sess_dev; 419 } 420 421 static struct rnbd_srv_dev *rnbd_srv_init_srv_dev(struct block_device *bdev) 422 { 423 struct rnbd_srv_dev *dev; 424 425 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 426 if (!dev) 427 return ERR_PTR(-ENOMEM); 428 429 snprintf(dev->id, sizeof(dev->id), "%pg", bdev); 430 kref_init(&dev->kref); 431 INIT_LIST_HEAD(&dev->sess_dev_list); 432 mutex_init(&dev->lock); 433 434 return dev; 435 } 436 437 static struct rnbd_srv_dev * 438 rnbd_srv_find_or_add_srv_dev(struct rnbd_srv_dev *new_dev) 439 { 440 struct rnbd_srv_dev *dev; 441 442 spin_lock(&dev_lock); 443 list_for_each_entry(dev, &dev_list, list) { 444 if (!strncmp(dev->id, new_dev->id, sizeof(dev->id))) { 445 if (!kref_get_unless_zero(&dev->kref)) 446 /* 447 * We lost the race, device is almost dead. 448 * Continue traversing to find a valid one. 449 */ 450 continue; 451 spin_unlock(&dev_lock); 452 return dev; 453 } 454 } 455 list_add(&new_dev->list, &dev_list); 456 spin_unlock(&dev_lock); 457 458 return new_dev; 459 } 460 461 static int rnbd_srv_check_update_open_perm(struct rnbd_srv_dev *srv_dev, 462 struct rnbd_srv_session *srv_sess, 463 enum rnbd_access_mode access_mode) 464 { 465 int ret = -EPERM; 466 467 mutex_lock(&srv_dev->lock); 468 469 switch (access_mode) { 470 case RNBD_ACCESS_RO: 471 ret = 0; 472 break; 473 case RNBD_ACCESS_RW: 474 if (srv_dev->open_write_cnt == 0) { 475 srv_dev->open_write_cnt++; 476 ret = 0; 477 } else { 478 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", 479 srv_dev->id, srv_sess->sessname, 480 srv_dev->open_write_cnt, 481 rnbd_access_mode_str(access_mode)); 482 } 483 break; 484 case RNBD_ACCESS_MIGRATION: 485 if (srv_dev->open_write_cnt < 2) { 486 srv_dev->open_write_cnt++; 487 ret = 0; 488 } else { 489 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", 490 srv_dev->id, srv_sess->sessname, 491 srv_dev->open_write_cnt, 492 rnbd_access_mode_str(access_mode)); 493 } 494 break; 495 default: 496 pr_err("Received mapping request for device '%s' on session %s with invalid access mode: %d\n", 497 srv_dev->id, srv_sess->sessname, access_mode); 498 ret = -EINVAL; 499 } 500 501 mutex_unlock(&srv_dev->lock); 502 503 return ret; 504 } 505 506 static struct rnbd_srv_dev * 507 rnbd_srv_get_or_create_srv_dev(struct rnbd_dev *rnbd_dev, 508 struct rnbd_srv_session *srv_sess, 509 enum rnbd_access_mode access_mode) 510 { 511 int ret; 512 struct rnbd_srv_dev *new_dev, *dev; 513 514 new_dev = rnbd_srv_init_srv_dev(rnbd_dev->bdev); 515 if (IS_ERR(new_dev)) 516 return new_dev; 517 518 dev = rnbd_srv_find_or_add_srv_dev(new_dev); 519 if (dev != new_dev) 520 kfree(new_dev); 521 522 ret = rnbd_srv_check_update_open_perm(dev, srv_sess, access_mode); 523 if (ret) { 524 rnbd_put_srv_dev(dev); 525 return ERR_PTR(ret); 526 } 527 528 return dev; 529 } 530 531 static void rnbd_srv_fill_msg_open_rsp(struct rnbd_msg_open_rsp *rsp, 532 struct rnbd_srv_sess_dev *sess_dev) 533 { 534 struct rnbd_dev *rnbd_dev = sess_dev->rnbd_dev; 535 536 rsp->hdr.type = cpu_to_le16(RNBD_MSG_OPEN_RSP); 537 rsp->device_id = 538 cpu_to_le32(sess_dev->device_id); 539 rsp->nsectors = 540 cpu_to_le64(get_capacity(rnbd_dev->bdev->bd_disk)); 541 rsp->logical_block_size = 542 cpu_to_le16(bdev_logical_block_size(rnbd_dev->bdev)); 543 rsp->physical_block_size = 544 cpu_to_le16(bdev_physical_block_size(rnbd_dev->bdev)); 545 rsp->max_segments = 546 cpu_to_le16(rnbd_dev_get_max_segs(rnbd_dev)); 547 rsp->max_hw_sectors = 548 cpu_to_le32(rnbd_dev_get_max_hw_sects(rnbd_dev)); 549 rsp->max_write_same_sectors = 0; 550 rsp->max_discard_sectors = 551 cpu_to_le32(rnbd_dev_get_max_discard_sects(rnbd_dev)); 552 rsp->discard_granularity = 553 cpu_to_le32(rnbd_dev_get_discard_granularity(rnbd_dev)); 554 rsp->discard_alignment = 555 cpu_to_le32(rnbd_dev_get_discard_alignment(rnbd_dev)); 556 rsp->secure_discard = 557 cpu_to_le16(rnbd_dev_get_secure_discard(rnbd_dev)); 558 rsp->cache_policy = 0; 559 if (bdev_write_cache(rnbd_dev->bdev)) 560 rsp->cache_policy |= RNBD_WRITEBACK; 561 if (bdev_fua(rnbd_dev->bdev)) 562 rsp->cache_policy |= RNBD_FUA; 563 } 564 565 static struct rnbd_srv_sess_dev * 566 rnbd_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 strscpy(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 } 588 589 static 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 } 637 638 static int process_msg_sess_info(struct rnbd_srv_session *srv_sess, 639 const void *msg, size_t len, 640 void *data, size_t datalen) 641 { 642 const struct rnbd_msg_sess_info *sess_info_msg = msg; 643 struct rnbd_msg_sess_info_rsp *rsp = data; 644 645 srv_sess->ver = min_t(u8, sess_info_msg->ver, RNBD_PROTO_VER_MAJOR); 646 pr_debug("Session %s using protocol version %d (client version: %d, server version: %d)\n", 647 srv_sess->sessname, srv_sess->ver, 648 sess_info_msg->ver, RNBD_PROTO_VER_MAJOR); 649 650 rsp->hdr.type = cpu_to_le16(RNBD_MSG_SESS_INFO_RSP); 651 rsp->ver = srv_sess->ver; 652 653 return 0; 654 } 655 656 /** 657 * find_srv_sess_dev() - a dev is already opened by this name 658 * @srv_sess: the session to search. 659 * @dev_name: string containing the name of the device. 660 * 661 * Return struct rnbd_srv_sess_dev if srv_sess already opened the dev_name 662 * NULL if the session didn't open the device yet. 663 */ 664 static struct rnbd_srv_sess_dev * 665 find_srv_sess_dev(struct rnbd_srv_session *srv_sess, const char *dev_name) 666 { 667 struct rnbd_srv_sess_dev *sess_dev; 668 unsigned long index; 669 670 if (xa_empty(&srv_sess->index_idr)) 671 return NULL; 672 673 xa_for_each(&srv_sess->index_idr, index, sess_dev) 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 if (ret) { 763 mutex_unlock(&srv_dev->lock); 764 rnbd_srv_err(srv_sess_dev, 765 "Opening device failed, failed to create device sysfs files, err: %d\n", 766 ret); 767 goto free_srv_sess_dev; 768 } 769 } 770 771 ret = rnbd_srv_create_dev_session_sysfs(srv_sess_dev); 772 if (ret) { 773 mutex_unlock(&srv_dev->lock); 774 rnbd_srv_err(srv_sess_dev, 775 "Opening device failed, failed to create dev client sysfs files, err: %d\n", 776 ret); 777 goto free_srv_sess_dev; 778 } 779 780 list_add(&srv_sess_dev->dev_list, &srv_dev->sess_dev_list); 781 mutex_unlock(&srv_dev->lock); 782 783 rnbd_srv_info(srv_sess_dev, "Opened device '%s'\n", srv_dev->id); 784 785 kfree(full_path); 786 787 fill_response: 788 rnbd_srv_fill_msg_open_rsp(rsp, srv_sess_dev); 789 mutex_unlock(&srv_sess->lock); 790 return 0; 791 792 free_srv_sess_dev: 793 xa_erase(&srv_sess->index_idr, srv_sess_dev->device_id); 794 synchronize_rcu(); 795 kfree(srv_sess_dev); 796 srv_dev_put: 797 if (open_msg->access_mode != RNBD_ACCESS_RO) { 798 mutex_lock(&srv_dev->lock); 799 srv_dev->open_write_cnt--; 800 mutex_unlock(&srv_dev->lock); 801 } 802 rnbd_put_srv_dev(srv_dev); 803 rnbd_dev_close: 804 rnbd_dev_close(rnbd_dev); 805 free_path: 806 kfree(full_path); 807 reject: 808 mutex_unlock(&srv_sess->lock); 809 return ret; 810 } 811 812 static struct rtrs_srv_ctx *rtrs_ctx; 813 814 static struct rtrs_srv_ops rtrs_ops; 815 static int __init rnbd_srv_init_module(void) 816 { 817 int err; 818 819 BUILD_BUG_ON(sizeof(struct rnbd_msg_hdr) != 4); 820 BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info) != 36); 821 BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info_rsp) != 36); 822 BUILD_BUG_ON(sizeof(struct rnbd_msg_open) != 264); 823 BUILD_BUG_ON(sizeof(struct rnbd_msg_close) != 8); 824 BUILD_BUG_ON(sizeof(struct rnbd_msg_open_rsp) != 56); 825 rtrs_ops = (struct rtrs_srv_ops) { 826 .rdma_ev = rnbd_srv_rdma_ev, 827 .link_ev = rnbd_srv_link_ev, 828 }; 829 rtrs_ctx = rtrs_srv_open(&rtrs_ops, port_nr); 830 if (IS_ERR(rtrs_ctx)) { 831 err = PTR_ERR(rtrs_ctx); 832 pr_err("rtrs_srv_open(), err: %d\n", err); 833 return err; 834 } 835 836 err = rnbd_srv_create_sysfs_files(); 837 if (err) { 838 pr_err("rnbd_srv_create_sysfs_files(), err: %d\n", err); 839 rtrs_srv_close(rtrs_ctx); 840 return err; 841 } 842 843 return 0; 844 } 845 846 static void __exit rnbd_srv_cleanup_module(void) 847 { 848 rtrs_srv_close(rtrs_ctx); 849 WARN_ON(!list_empty(&sess_list)); 850 rnbd_srv_destroy_sysfs_files(); 851 } 852 853 module_init(rnbd_srv_init_module); 854 module_exit(rnbd_srv_cleanup_module); 855