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-trace.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 static struct rnbd_srv_sess_dev * 88 rnbd_get_sess_dev(int dev_id, struct rnbd_srv_session *srv_sess) 89 { 90 struct rnbd_srv_sess_dev *sess_dev; 91 int ret = 0; 92 93 rcu_read_lock(); 94 sess_dev = xa_load(&srv_sess->index_idr, dev_id); 95 if (sess_dev) 96 ret = kref_get_unless_zero(&sess_dev->kref); 97 rcu_read_unlock(); 98 99 if (!ret) 100 return ERR_PTR(-ENXIO); 101 102 return sess_dev; 103 } 104 105 static void rnbd_dev_bi_end_io(struct bio *bio) 106 { 107 struct rnbd_io_private *rnbd_priv = bio->bi_private; 108 struct rnbd_srv_sess_dev *sess_dev = rnbd_priv->sess_dev; 109 110 rnbd_put_sess_dev(sess_dev); 111 rtrs_srv_resp_rdma(rnbd_priv->id, blk_status_to_errno(bio->bi_status)); 112 113 kfree(rnbd_priv); 114 bio_put(bio); 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 bio *bio; 127 short prio; 128 129 trace_process_rdma(srv_sess, msg, id, datalen, usrlen); 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 bio = bio_alloc(sess_dev->bdev, 1, 149 rnbd_to_bio_flags(le32_to_cpu(msg->rw)), GFP_KERNEL); 150 if (bio_add_page(bio, virt_to_page(data), datalen, 151 offset_in_page(data)) != datalen) { 152 rnbd_srv_err(sess_dev, "Failed to map data to bio\n"); 153 err = -EINVAL; 154 goto bio_put; 155 } 156 157 bio->bi_end_io = rnbd_dev_bi_end_io; 158 bio->bi_private = priv; 159 bio->bi_iter.bi_sector = le64_to_cpu(msg->sector); 160 bio->bi_iter.bi_size = le32_to_cpu(msg->bi_size); 161 prio = srv_sess->ver < RNBD_PROTO_VER_MAJOR || 162 usrlen < sizeof(*msg) ? 0 : le16_to_cpu(msg->prio); 163 bio_set_prio(bio, prio); 164 165 submit_bio(bio); 166 167 return 0; 168 169 bio_put: 170 bio_put(bio); 171 rnbd_put_sess_dev(sess_dev); 172 err: 173 kfree(priv); 174 return err; 175 } 176 177 static void destroy_device(struct kref *kref) 178 { 179 struct rnbd_srv_dev *dev = container_of(kref, struct rnbd_srv_dev, kref); 180 181 WARN_ONCE(!list_empty(&dev->sess_dev_list), 182 "Device %s is being destroyed but still in use!\n", 183 dev->name); 184 185 spin_lock(&dev_lock); 186 list_del(&dev->list); 187 spin_unlock(&dev_lock); 188 189 mutex_destroy(&dev->lock); 190 if (dev->dev_kobj.state_in_sysfs) 191 /* 192 * Destroy kobj only if it was really created. 193 */ 194 rnbd_srv_destroy_dev_sysfs(dev); 195 else 196 kfree(dev); 197 } 198 199 static void rnbd_put_srv_dev(struct rnbd_srv_dev *dev) 200 { 201 kref_put(&dev->kref, destroy_device); 202 } 203 204 void rnbd_destroy_sess_dev(struct rnbd_srv_sess_dev *sess_dev, bool keep_id) 205 { 206 DECLARE_COMPLETION_ONSTACK(dc); 207 208 if (keep_id) 209 /* free the resources for the id but don't */ 210 /* allow to re-use the id itself because it */ 211 /* is still used by the client */ 212 xa_cmpxchg(&sess_dev->sess->index_idr, sess_dev->device_id, 213 sess_dev, NULL, 0); 214 else 215 xa_erase(&sess_dev->sess->index_idr, sess_dev->device_id); 216 synchronize_rcu(); 217 218 sess_dev->destroy_comp = &dc; 219 rnbd_put_sess_dev(sess_dev); 220 wait_for_completion(&dc); /* wait for inflights to drop to zero */ 221 222 blkdev_put(sess_dev->bdev, NULL); 223 mutex_lock(&sess_dev->dev->lock); 224 list_del(&sess_dev->dev_list); 225 if (!sess_dev->readonly) 226 sess_dev->dev->open_write_cnt--; 227 mutex_unlock(&sess_dev->dev->lock); 228 229 rnbd_put_srv_dev(sess_dev->dev); 230 231 rnbd_srv_info(sess_dev, "Device closed\n"); 232 kfree(sess_dev); 233 } 234 235 static void destroy_sess(struct rnbd_srv_session *srv_sess) 236 { 237 struct rnbd_srv_sess_dev *sess_dev; 238 unsigned long index; 239 240 if (xa_empty(&srv_sess->index_idr)) 241 goto out; 242 243 trace_destroy_sess(srv_sess); 244 245 mutex_lock(&srv_sess->lock); 246 xa_for_each(&srv_sess->index_idr, index, sess_dev) 247 rnbd_srv_destroy_dev_session_sysfs(sess_dev); 248 mutex_unlock(&srv_sess->lock); 249 250 out: 251 xa_destroy(&srv_sess->index_idr); 252 253 pr_info("RTRS Session %s disconnected\n", srv_sess->sessname); 254 255 mutex_lock(&sess_lock); 256 list_del(&srv_sess->list); 257 mutex_unlock(&sess_lock); 258 259 mutex_destroy(&srv_sess->lock); 260 kfree(srv_sess); 261 } 262 263 static int create_sess(struct rtrs_srv_sess *rtrs) 264 { 265 struct rnbd_srv_session *srv_sess; 266 char pathname[NAME_MAX]; 267 int err; 268 269 err = rtrs_srv_get_path_name(rtrs, pathname, sizeof(pathname)); 270 if (err) { 271 pr_err("rtrs_srv_get_path_name(%s): %d\n", pathname, err); 272 273 return err; 274 } 275 srv_sess = kzalloc(sizeof(*srv_sess), GFP_KERNEL); 276 if (!srv_sess) 277 return -ENOMEM; 278 279 srv_sess->queue_depth = rtrs_srv_get_queue_depth(rtrs); 280 xa_init_flags(&srv_sess->index_idr, XA_FLAGS_ALLOC); 281 mutex_init(&srv_sess->lock); 282 mutex_lock(&sess_lock); 283 list_add(&srv_sess->list, &sess_list); 284 mutex_unlock(&sess_lock); 285 286 srv_sess->rtrs = rtrs; 287 strscpy(srv_sess->sessname, pathname, sizeof(srv_sess->sessname)); 288 289 rtrs_srv_set_sess_priv(rtrs, srv_sess); 290 291 trace_create_sess(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 void 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 trace_process_msg_close(srv_sess, close_msg); 343 344 sess_dev = rnbd_get_sess_dev(le32_to_cpu(close_msg->device_id), 345 srv_sess); 346 if (IS_ERR(sess_dev)) 347 return; 348 349 rnbd_put_sess_dev(sess_dev); 350 mutex_lock(&srv_sess->lock); 351 rnbd_srv_destroy_dev_session_sysfs(sess_dev); 352 mutex_unlock(&srv_sess->lock); 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 void 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, struct rtrs_srv_op *id, 364 void *data, size_t datalen, 365 const void *usr, 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 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 process_msg_sess_info(srv_sess, usr, usrlen, data, datalen); 388 break; 389 default: 390 pr_warn("Received unexpected message type %d from session %s\n", 391 type, srv_sess->sessname); 392 return -EINVAL; 393 } 394 395 /* 396 * Since ret is passed to rtrs to handle the failure case, we 397 * just return 0 at the end otherwise callers in rtrs would call 398 * send_io_resp_imm again to print redundant err message. 399 */ 400 rtrs_srv_resp_rdma(id, ret); 401 return 0; 402 } 403 404 static struct rnbd_srv_sess_dev 405 *rnbd_sess_dev_alloc(struct rnbd_srv_session *srv_sess) 406 { 407 struct rnbd_srv_sess_dev *sess_dev; 408 int error; 409 410 sess_dev = kzalloc(sizeof(*sess_dev), GFP_KERNEL); 411 if (!sess_dev) 412 return ERR_PTR(-ENOMEM); 413 414 error = xa_alloc(&srv_sess->index_idr, &sess_dev->device_id, sess_dev, 415 xa_limit_32b, GFP_NOWAIT); 416 if (error < 0) { 417 pr_warn("Allocating idr failed, err: %d\n", error); 418 kfree(sess_dev); 419 return ERR_PTR(error); 420 } 421 422 return sess_dev; 423 } 424 425 static struct rnbd_srv_dev *rnbd_srv_init_srv_dev(struct block_device *bdev) 426 { 427 struct rnbd_srv_dev *dev; 428 429 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 430 if (!dev) 431 return ERR_PTR(-ENOMEM); 432 433 snprintf(dev->name, sizeof(dev->name), "%pg", bdev); 434 kref_init(&dev->kref); 435 INIT_LIST_HEAD(&dev->sess_dev_list); 436 mutex_init(&dev->lock); 437 438 return dev; 439 } 440 441 static struct rnbd_srv_dev * 442 rnbd_srv_find_or_add_srv_dev(struct rnbd_srv_dev *new_dev) 443 { 444 struct rnbd_srv_dev *dev; 445 446 spin_lock(&dev_lock); 447 list_for_each_entry(dev, &dev_list, list) { 448 if (!strncmp(dev->name, new_dev->name, sizeof(dev->name))) { 449 if (!kref_get_unless_zero(&dev->kref)) 450 /* 451 * We lost the race, device is almost dead. 452 * Continue traversing to find a valid one. 453 */ 454 continue; 455 spin_unlock(&dev_lock); 456 return dev; 457 } 458 } 459 list_add(&new_dev->list, &dev_list); 460 spin_unlock(&dev_lock); 461 462 return new_dev; 463 } 464 465 static int rnbd_srv_check_update_open_perm(struct rnbd_srv_dev *srv_dev, 466 struct rnbd_srv_session *srv_sess, 467 enum rnbd_access_mode access_mode) 468 { 469 int ret = 0; 470 471 mutex_lock(&srv_dev->lock); 472 473 switch (access_mode) { 474 case RNBD_ACCESS_RO: 475 break; 476 case RNBD_ACCESS_RW: 477 if (srv_dev->open_write_cnt == 0) { 478 srv_dev->open_write_cnt++; 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->name, srv_sess->sessname, 482 srv_dev->open_write_cnt, 483 rnbd_access_modes[access_mode].str); 484 ret = -EPERM; 485 } 486 break; 487 case RNBD_ACCESS_MIGRATION: 488 if (srv_dev->open_write_cnt < 2) { 489 srv_dev->open_write_cnt++; 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->name, srv_sess->sessname, 493 srv_dev->open_write_cnt, 494 rnbd_access_modes[access_mode].str); 495 ret = -EPERM; 496 } 497 break; 498 default: 499 pr_err("Received mapping request for device '%s' on session %s with invalid access mode: %d\n", 500 srv_dev->name, srv_sess->sessname, access_mode); 501 ret = -EINVAL; 502 } 503 504 mutex_unlock(&srv_dev->lock); 505 506 return ret; 507 } 508 509 static struct rnbd_srv_dev * 510 rnbd_srv_get_or_create_srv_dev(struct block_device *bdev, 511 struct rnbd_srv_session *srv_sess, 512 enum rnbd_access_mode access_mode) 513 { 514 int ret; 515 struct rnbd_srv_dev *new_dev, *dev; 516 517 new_dev = rnbd_srv_init_srv_dev(bdev); 518 if (IS_ERR(new_dev)) 519 return new_dev; 520 521 dev = rnbd_srv_find_or_add_srv_dev(new_dev); 522 if (dev != new_dev) 523 kfree(new_dev); 524 525 ret = rnbd_srv_check_update_open_perm(dev, srv_sess, access_mode); 526 if (ret) { 527 rnbd_put_srv_dev(dev); 528 return ERR_PTR(ret); 529 } 530 531 return dev; 532 } 533 534 static void rnbd_srv_fill_msg_open_rsp(struct rnbd_msg_open_rsp *rsp, 535 struct rnbd_srv_sess_dev *sess_dev) 536 { 537 struct block_device *bdev = sess_dev->bdev; 538 539 rsp->hdr.type = cpu_to_le16(RNBD_MSG_OPEN_RSP); 540 rsp->device_id = cpu_to_le32(sess_dev->device_id); 541 rsp->nsectors = cpu_to_le64(bdev_nr_sectors(bdev)); 542 rsp->logical_block_size = cpu_to_le16(bdev_logical_block_size(bdev)); 543 rsp->physical_block_size = cpu_to_le16(bdev_physical_block_size(bdev)); 544 rsp->max_segments = cpu_to_le16(bdev_max_segments(bdev)); 545 rsp->max_hw_sectors = 546 cpu_to_le32(queue_max_hw_sectors(bdev_get_queue(bdev))); 547 rsp->max_write_same_sectors = 0; 548 rsp->max_discard_sectors = cpu_to_le32(bdev_max_discard_sectors(bdev)); 549 rsp->discard_granularity = cpu_to_le32(bdev_discard_granularity(bdev)); 550 rsp->discard_alignment = cpu_to_le32(bdev_discard_alignment(bdev)); 551 rsp->secure_discard = cpu_to_le16(bdev_max_secure_erase_sectors(bdev)); 552 rsp->cache_policy = 0; 553 if (bdev_write_cache(bdev)) 554 rsp->cache_policy |= RNBD_WRITEBACK; 555 if (bdev_fua(bdev)) 556 rsp->cache_policy |= RNBD_FUA; 557 } 558 559 static struct rnbd_srv_sess_dev * 560 rnbd_srv_create_set_sess_dev(struct rnbd_srv_session *srv_sess, 561 const struct rnbd_msg_open *open_msg, 562 struct block_device *bdev, bool readonly, 563 struct rnbd_srv_dev *srv_dev) 564 { 565 struct rnbd_srv_sess_dev *sdev = rnbd_sess_dev_alloc(srv_sess); 566 567 if (IS_ERR(sdev)) 568 return sdev; 569 570 kref_init(&sdev->kref); 571 572 strscpy(sdev->pathname, open_msg->dev_name, sizeof(sdev->pathname)); 573 574 sdev->bdev = bdev; 575 sdev->sess = srv_sess; 576 sdev->dev = srv_dev; 577 sdev->readonly = readonly; 578 sdev->access_mode = open_msg->access_mode; 579 580 return sdev; 581 } 582 583 static char *rnbd_srv_get_full_path(struct rnbd_srv_session *srv_sess, 584 const char *dev_name) 585 { 586 char *full_path; 587 char *a, *b; 588 int len; 589 590 full_path = kmalloc(PATH_MAX, GFP_KERNEL); 591 if (!full_path) 592 return ERR_PTR(-ENOMEM); 593 594 /* 595 * Replace %SESSNAME% with a real session name in order to 596 * create device namespace. 597 */ 598 a = strnstr(dev_search_path, "%SESSNAME%", sizeof(dev_search_path)); 599 if (a) { 600 len = a - dev_search_path; 601 602 len = snprintf(full_path, PATH_MAX, "%.*s/%s/%s", len, 603 dev_search_path, srv_sess->sessname, dev_name); 604 } else { 605 len = snprintf(full_path, PATH_MAX, "%s/%s", 606 dev_search_path, dev_name); 607 } 608 if (len >= PATH_MAX) { 609 pr_err("Too long path: %s, %s, %s\n", 610 dev_search_path, srv_sess->sessname, dev_name); 611 kfree(full_path); 612 return ERR_PTR(-EINVAL); 613 } 614 615 /* eliminitate duplicated slashes */ 616 a = strchr(full_path, '/'); 617 b = a; 618 while (*b != '\0') { 619 if (*b == '/' && *a == '/') { 620 b++; 621 } else { 622 a++; 623 *a = *b; 624 b++; 625 } 626 } 627 a++; 628 *a = '\0'; 629 630 return full_path; 631 } 632 633 static void process_msg_sess_info(struct rnbd_srv_session *srv_sess, 634 const void *msg, size_t len, 635 void *data, size_t datalen) 636 { 637 const struct rnbd_msg_sess_info *sess_info_msg = msg; 638 struct rnbd_msg_sess_info_rsp *rsp = data; 639 640 srv_sess->ver = min_t(u8, sess_info_msg->ver, RNBD_PROTO_VER_MAJOR); 641 642 trace_process_msg_sess_info(srv_sess, sess_info_msg); 643 644 rsp->hdr.type = cpu_to_le16(RNBD_MSG_SESS_INFO_RSP); 645 rsp->ver = srv_sess->ver; 646 } 647 648 /** 649 * find_srv_sess_dev() - a dev is already opened by this name 650 * @srv_sess: the session to search. 651 * @dev_name: string containing the name of the device. 652 * 653 * Return struct rnbd_srv_sess_dev if srv_sess already opened the dev_name 654 * NULL if the session didn't open the device yet. 655 */ 656 static struct rnbd_srv_sess_dev * 657 find_srv_sess_dev(struct rnbd_srv_session *srv_sess, const char *dev_name) 658 { 659 struct rnbd_srv_sess_dev *sess_dev; 660 unsigned long index; 661 662 if (xa_empty(&srv_sess->index_idr)) 663 return NULL; 664 665 xa_for_each(&srv_sess->index_idr, index, sess_dev) 666 if (!strcmp(sess_dev->pathname, dev_name)) 667 return sess_dev; 668 669 return NULL; 670 } 671 672 static int process_msg_open(struct rnbd_srv_session *srv_sess, 673 const void *msg, size_t len, 674 void *data, size_t datalen) 675 { 676 int ret; 677 struct rnbd_srv_dev *srv_dev; 678 struct rnbd_srv_sess_dev *srv_sess_dev; 679 const struct rnbd_msg_open *open_msg = msg; 680 struct block_device *bdev; 681 blk_mode_t open_flags = BLK_OPEN_READ; 682 char *full_path; 683 struct rnbd_msg_open_rsp *rsp = data; 684 685 trace_process_msg_open(srv_sess, open_msg); 686 687 if (open_msg->access_mode != RNBD_ACCESS_RO) 688 open_flags |= BLK_OPEN_WRITE; 689 690 mutex_lock(&srv_sess->lock); 691 692 srv_sess_dev = find_srv_sess_dev(srv_sess, open_msg->dev_name); 693 if (srv_sess_dev) 694 goto fill_response; 695 696 if ((strlen(dev_search_path) + strlen(open_msg->dev_name)) 697 >= PATH_MAX) { 698 pr_err("Opening device for session %s failed, device path too long. '%s/%s' is longer than PATH_MAX (%d)\n", 699 srv_sess->sessname, dev_search_path, open_msg->dev_name, 700 PATH_MAX); 701 ret = -EINVAL; 702 goto reject; 703 } 704 if (strstr(open_msg->dev_name, "..")) { 705 pr_err("Opening device for session %s failed, device path %s contains relative path ..\n", 706 srv_sess->sessname, open_msg->dev_name); 707 ret = -EINVAL; 708 goto reject; 709 } 710 full_path = rnbd_srv_get_full_path(srv_sess, open_msg->dev_name); 711 if (IS_ERR(full_path)) { 712 ret = PTR_ERR(full_path); 713 pr_err("Opening device '%s' for client %s failed, failed to get device full path, err: %d\n", 714 open_msg->dev_name, srv_sess->sessname, ret); 715 goto reject; 716 } 717 718 bdev = blkdev_get_by_path(full_path, open_flags, NULL, NULL); 719 if (IS_ERR(bdev)) { 720 ret = PTR_ERR(bdev); 721 pr_err("Opening device '%s' on session %s failed, failed to open the block device, err: %d\n", 722 full_path, srv_sess->sessname, ret); 723 goto free_path; 724 } 725 726 srv_dev = rnbd_srv_get_or_create_srv_dev(bdev, srv_sess, 727 open_msg->access_mode); 728 if (IS_ERR(srv_dev)) { 729 pr_err("Opening device '%s' on session %s failed, creating srv_dev failed, err: %ld\n", 730 full_path, srv_sess->sessname, PTR_ERR(srv_dev)); 731 ret = PTR_ERR(srv_dev); 732 goto blkdev_put; 733 } 734 735 srv_sess_dev = rnbd_srv_create_set_sess_dev(srv_sess, open_msg, bdev, 736 open_msg->access_mode == RNBD_ACCESS_RO, 737 srv_dev); 738 if (IS_ERR(srv_sess_dev)) { 739 pr_err("Opening device '%s' on session %s failed, creating sess_dev failed, err: %ld\n", 740 full_path, srv_sess->sessname, PTR_ERR(srv_sess_dev)); 741 ret = PTR_ERR(srv_sess_dev); 742 goto srv_dev_put; 743 } 744 745 /* Create the srv_dev sysfs files if they haven't been created yet. The 746 * reason to delay the creation is not to create the sysfs files before 747 * we are sure the device can be opened. 748 */ 749 mutex_lock(&srv_dev->lock); 750 if (!srv_dev->dev_kobj.state_in_sysfs) { 751 ret = rnbd_srv_create_dev_sysfs(srv_dev, bdev); 752 if (ret) { 753 mutex_unlock(&srv_dev->lock); 754 rnbd_srv_err(srv_sess_dev, 755 "Opening device failed, failed to create device sysfs files, err: %d\n", 756 ret); 757 goto free_srv_sess_dev; 758 } 759 } 760 761 ret = rnbd_srv_create_dev_session_sysfs(srv_sess_dev); 762 if (ret) { 763 mutex_unlock(&srv_dev->lock); 764 rnbd_srv_err(srv_sess_dev, 765 "Opening device failed, failed to create dev client sysfs files, err: %d\n", 766 ret); 767 goto free_srv_sess_dev; 768 } 769 770 list_add(&srv_sess_dev->dev_list, &srv_dev->sess_dev_list); 771 mutex_unlock(&srv_dev->lock); 772 773 rnbd_srv_info(srv_sess_dev, "Opened device '%s'\n", srv_dev->name); 774 775 kfree(full_path); 776 777 fill_response: 778 rnbd_srv_fill_msg_open_rsp(rsp, srv_sess_dev); 779 mutex_unlock(&srv_sess->lock); 780 return 0; 781 782 free_srv_sess_dev: 783 xa_erase(&srv_sess->index_idr, srv_sess_dev->device_id); 784 synchronize_rcu(); 785 kfree(srv_sess_dev); 786 srv_dev_put: 787 if (open_msg->access_mode != RNBD_ACCESS_RO) { 788 mutex_lock(&srv_dev->lock); 789 srv_dev->open_write_cnt--; 790 mutex_unlock(&srv_dev->lock); 791 } 792 rnbd_put_srv_dev(srv_dev); 793 blkdev_put: 794 blkdev_put(bdev, NULL); 795 free_path: 796 kfree(full_path); 797 reject: 798 mutex_unlock(&srv_sess->lock); 799 return ret; 800 } 801 802 static struct rtrs_srv_ctx *rtrs_ctx; 803 804 static struct rtrs_srv_ops rtrs_ops; 805 static int __init rnbd_srv_init_module(void) 806 { 807 int err = 0; 808 809 BUILD_BUG_ON(sizeof(struct rnbd_msg_hdr) != 4); 810 BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info) != 36); 811 BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info_rsp) != 36); 812 BUILD_BUG_ON(sizeof(struct rnbd_msg_open) != 264); 813 BUILD_BUG_ON(sizeof(struct rnbd_msg_close) != 8); 814 BUILD_BUG_ON(sizeof(struct rnbd_msg_open_rsp) != 56); 815 rtrs_ops = (struct rtrs_srv_ops) { 816 .rdma_ev = rnbd_srv_rdma_ev, 817 .link_ev = rnbd_srv_link_ev, 818 }; 819 rtrs_ctx = rtrs_srv_open(&rtrs_ops, port_nr); 820 if (IS_ERR(rtrs_ctx)) { 821 pr_err("rtrs_srv_open(), err: %d\n", err); 822 return PTR_ERR(rtrs_ctx); 823 } 824 825 err = rnbd_srv_create_sysfs_files(); 826 if (err) { 827 pr_err("rnbd_srv_create_sysfs_files(), err: %d\n", err); 828 rtrs_srv_close(rtrs_ctx); 829 } 830 831 return err; 832 } 833 834 static void __exit rnbd_srv_cleanup_module(void) 835 { 836 rtrs_srv_close(rtrs_ctx); 837 WARN_ON(!list_empty(&sess_list)); 838 rnbd_srv_destroy_sysfs_files(); 839 } 840 841 module_init(rnbd_srv_init_module); 842 module_exit(rnbd_srv_cleanup_module); 843