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->id); 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, sess_dev->open_flags); 223 mutex_lock(&sess_dev->dev->lock); 224 list_del(&sess_dev->dev_list); 225 if (sess_dev->open_flags & FMODE_WRITE) 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 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, 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 ret = process_msg_sess_info(srv_sess, usr, usrlen, data, 388 datalen); 389 break; 390 default: 391 pr_warn("Received unexpected message type %d from session %s\n", 392 type, srv_sess->sessname); 393 return -EINVAL; 394 } 395 396 /* 397 * Since ret is passed to rtrs to handle the failure case, we 398 * just return 0 at the end otherwise callers in rtrs would call 399 * send_io_resp_imm again to print redundant err message. 400 */ 401 rtrs_srv_resp_rdma(id, ret); 402 return 0; 403 } 404 405 static struct rnbd_srv_sess_dev 406 *rnbd_sess_dev_alloc(struct rnbd_srv_session *srv_sess) 407 { 408 struct rnbd_srv_sess_dev *sess_dev; 409 int error; 410 411 sess_dev = kzalloc(sizeof(*sess_dev), GFP_KERNEL); 412 if (!sess_dev) 413 return ERR_PTR(-ENOMEM); 414 415 error = xa_alloc(&srv_sess->index_idr, &sess_dev->device_id, sess_dev, 416 xa_limit_32b, GFP_NOWAIT); 417 if (error < 0) { 418 pr_warn("Allocating idr failed, err: %d\n", error); 419 kfree(sess_dev); 420 return ERR_PTR(error); 421 } 422 423 return sess_dev; 424 } 425 426 static struct rnbd_srv_dev *rnbd_srv_init_srv_dev(struct block_device *bdev) 427 { 428 struct rnbd_srv_dev *dev; 429 430 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 431 if (!dev) 432 return ERR_PTR(-ENOMEM); 433 434 snprintf(dev->id, sizeof(dev->id), "%pg", bdev); 435 kref_init(&dev->kref); 436 INIT_LIST_HEAD(&dev->sess_dev_list); 437 mutex_init(&dev->lock); 438 439 return dev; 440 } 441 442 static struct rnbd_srv_dev * 443 rnbd_srv_find_or_add_srv_dev(struct rnbd_srv_dev *new_dev) 444 { 445 struct rnbd_srv_dev *dev; 446 447 spin_lock(&dev_lock); 448 list_for_each_entry(dev, &dev_list, list) { 449 if (!strncmp(dev->id, new_dev->id, sizeof(dev->id))) { 450 if (!kref_get_unless_zero(&dev->kref)) 451 /* 452 * We lost the race, device is almost dead. 453 * Continue traversing to find a valid one. 454 */ 455 continue; 456 spin_unlock(&dev_lock); 457 return dev; 458 } 459 } 460 list_add(&new_dev->list, &dev_list); 461 spin_unlock(&dev_lock); 462 463 return new_dev; 464 } 465 466 static int rnbd_srv_check_update_open_perm(struct rnbd_srv_dev *srv_dev, 467 struct rnbd_srv_session *srv_sess, 468 enum rnbd_access_mode access_mode) 469 { 470 int ret = -EPERM; 471 472 mutex_lock(&srv_dev->lock); 473 474 switch (access_mode) { 475 case RNBD_ACCESS_RO: 476 ret = 0; 477 break; 478 case RNBD_ACCESS_RW: 479 if (srv_dev->open_write_cnt == 0) { 480 srv_dev->open_write_cnt++; 481 ret = 0; 482 } else { 483 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", 484 srv_dev->id, srv_sess->sessname, 485 srv_dev->open_write_cnt, 486 rnbd_access_modes[access_mode].str); 487 } 488 break; 489 case RNBD_ACCESS_MIGRATION: 490 if (srv_dev->open_write_cnt < 2) { 491 srv_dev->open_write_cnt++; 492 ret = 0; 493 } else { 494 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", 495 srv_dev->id, srv_sess->sessname, 496 srv_dev->open_write_cnt, 497 rnbd_access_modes[access_mode].str); 498 } 499 break; 500 default: 501 pr_err("Received mapping request for device '%s' on session %s with invalid access mode: %d\n", 502 srv_dev->id, srv_sess->sessname, access_mode); 503 ret = -EINVAL; 504 } 505 506 mutex_unlock(&srv_dev->lock); 507 508 return ret; 509 } 510 511 static struct rnbd_srv_dev * 512 rnbd_srv_get_or_create_srv_dev(struct block_device *bdev, 513 struct rnbd_srv_session *srv_sess, 514 enum rnbd_access_mode access_mode) 515 { 516 int ret; 517 struct rnbd_srv_dev *new_dev, *dev; 518 519 new_dev = rnbd_srv_init_srv_dev(bdev); 520 if (IS_ERR(new_dev)) 521 return new_dev; 522 523 dev = rnbd_srv_find_or_add_srv_dev(new_dev); 524 if (dev != new_dev) 525 kfree(new_dev); 526 527 ret = rnbd_srv_check_update_open_perm(dev, srv_sess, access_mode); 528 if (ret) { 529 rnbd_put_srv_dev(dev); 530 return ERR_PTR(ret); 531 } 532 533 return dev; 534 } 535 536 static void rnbd_srv_fill_msg_open_rsp(struct rnbd_msg_open_rsp *rsp, 537 struct rnbd_srv_sess_dev *sess_dev) 538 { 539 struct block_device *bdev = sess_dev->bdev; 540 541 rsp->hdr.type = cpu_to_le16(RNBD_MSG_OPEN_RSP); 542 rsp->device_id = cpu_to_le32(sess_dev->device_id); 543 rsp->nsectors = cpu_to_le64(bdev_nr_sectors(bdev)); 544 rsp->logical_block_size = cpu_to_le16(bdev_logical_block_size(bdev)); 545 rsp->physical_block_size = cpu_to_le16(bdev_physical_block_size(bdev)); 546 rsp->max_segments = cpu_to_le16(bdev_max_segments(bdev)); 547 rsp->max_hw_sectors = 548 cpu_to_le32(queue_max_hw_sectors(bdev_get_queue(bdev))); 549 rsp->max_write_same_sectors = 0; 550 rsp->max_discard_sectors = cpu_to_le32(bdev_max_discard_sectors(bdev)); 551 rsp->discard_granularity = cpu_to_le32(bdev_discard_granularity(bdev)); 552 rsp->discard_alignment = cpu_to_le32(bdev_discard_alignment(bdev)); 553 rsp->secure_discard = cpu_to_le16(bdev_max_secure_erase_sectors(bdev)); 554 rsp->cache_policy = 0; 555 if (bdev_write_cache(bdev)) 556 rsp->cache_policy |= RNBD_WRITEBACK; 557 if (bdev_fua(bdev)) 558 rsp->cache_policy |= RNBD_FUA; 559 } 560 561 static struct rnbd_srv_sess_dev * 562 rnbd_srv_create_set_sess_dev(struct rnbd_srv_session *srv_sess, 563 const struct rnbd_msg_open *open_msg, 564 struct block_device *bdev, fmode_t open_flags, 565 struct rnbd_srv_dev *srv_dev) 566 { 567 struct rnbd_srv_sess_dev *sdev = rnbd_sess_dev_alloc(srv_sess); 568 569 if (IS_ERR(sdev)) 570 return sdev; 571 572 kref_init(&sdev->kref); 573 574 strscpy(sdev->pathname, open_msg->dev_name, sizeof(sdev->pathname)); 575 576 sdev->bdev = bdev; 577 sdev->sess = srv_sess; 578 sdev->dev = srv_dev; 579 sdev->open_flags = open_flags; 580 sdev->access_mode = open_msg->access_mode; 581 582 return sdev; 583 } 584 585 static char *rnbd_srv_get_full_path(struct rnbd_srv_session *srv_sess, 586 const char *dev_name) 587 { 588 char *full_path; 589 char *a, *b; 590 591 full_path = kmalloc(PATH_MAX, GFP_KERNEL); 592 if (!full_path) 593 return ERR_PTR(-ENOMEM); 594 595 /* 596 * Replace %SESSNAME% with a real session name in order to 597 * create device namespace. 598 */ 599 a = strnstr(dev_search_path, "%SESSNAME%", sizeof(dev_search_path)); 600 if (a) { 601 int len = a - dev_search_path; 602 603 len = snprintf(full_path, PATH_MAX, "%.*s/%s/%s", len, 604 dev_search_path, srv_sess->sessname, dev_name); 605 if (len >= PATH_MAX) { 606 pr_err("Too long path: %s, %s, %s\n", 607 dev_search_path, srv_sess->sessname, dev_name); 608 kfree(full_path); 609 return ERR_PTR(-EINVAL); 610 } 611 } else { 612 snprintf(full_path, PATH_MAX, "%s/%s", 613 dev_search_path, dev_name); 614 } 615 616 /* eliminitate duplicated slashes */ 617 a = strchr(full_path, '/'); 618 b = a; 619 while (*b != '\0') { 620 if (*b == '/' && *a == '/') { 621 b++; 622 } else { 623 a++; 624 *a = *b; 625 b++; 626 } 627 } 628 a++; 629 *a = '\0'; 630 631 return full_path; 632 } 633 634 static int process_msg_sess_info(struct rnbd_srv_session *srv_sess, 635 const void *msg, size_t len, 636 void *data, size_t datalen) 637 { 638 const struct rnbd_msg_sess_info *sess_info_msg = msg; 639 struct rnbd_msg_sess_info_rsp *rsp = data; 640 641 srv_sess->ver = min_t(u8, sess_info_msg->ver, RNBD_PROTO_VER_MAJOR); 642 643 trace_process_msg_sess_info(srv_sess, sess_info_msg); 644 645 rsp->hdr.type = cpu_to_le16(RNBD_MSG_SESS_INFO_RSP); 646 rsp->ver = srv_sess->ver; 647 648 return 0; 649 } 650 651 /** 652 * find_srv_sess_dev() - a dev is already opened by this name 653 * @srv_sess: the session to search. 654 * @dev_name: string containing the name of the device. 655 * 656 * Return struct rnbd_srv_sess_dev if srv_sess already opened the dev_name 657 * NULL if the session didn't open the device yet. 658 */ 659 static struct rnbd_srv_sess_dev * 660 find_srv_sess_dev(struct rnbd_srv_session *srv_sess, const char *dev_name) 661 { 662 struct rnbd_srv_sess_dev *sess_dev; 663 unsigned long index; 664 665 if (xa_empty(&srv_sess->index_idr)) 666 return NULL; 667 668 xa_for_each(&srv_sess->index_idr, index, sess_dev) 669 if (!strcmp(sess_dev->pathname, dev_name)) 670 return sess_dev; 671 672 return NULL; 673 } 674 675 static int process_msg_open(struct rnbd_srv_session *srv_sess, 676 const void *msg, size_t len, 677 void *data, size_t datalen) 678 { 679 int ret; 680 struct rnbd_srv_dev *srv_dev; 681 struct rnbd_srv_sess_dev *srv_sess_dev; 682 const struct rnbd_msg_open *open_msg = msg; 683 struct block_device *bdev; 684 fmode_t open_flags; 685 char *full_path; 686 struct rnbd_msg_open_rsp *rsp = data; 687 688 trace_process_msg_open(srv_sess, open_msg); 689 690 open_flags = FMODE_READ; 691 if (open_msg->access_mode != RNBD_ACCESS_RO) 692 open_flags |= FMODE_WRITE; 693 694 mutex_lock(&srv_sess->lock); 695 696 srv_sess_dev = find_srv_sess_dev(srv_sess, open_msg->dev_name); 697 if (srv_sess_dev) 698 goto fill_response; 699 700 if ((strlen(dev_search_path) + strlen(open_msg->dev_name)) 701 >= PATH_MAX) { 702 pr_err("Opening device for session %s failed, device path too long. '%s/%s' is longer than PATH_MAX (%d)\n", 703 srv_sess->sessname, dev_search_path, open_msg->dev_name, 704 PATH_MAX); 705 ret = -EINVAL; 706 goto reject; 707 } 708 if (strstr(open_msg->dev_name, "..")) { 709 pr_err("Opening device for session %s failed, device path %s contains relative path ..\n", 710 srv_sess->sessname, open_msg->dev_name); 711 ret = -EINVAL; 712 goto reject; 713 } 714 full_path = rnbd_srv_get_full_path(srv_sess, open_msg->dev_name); 715 if (IS_ERR(full_path)) { 716 ret = PTR_ERR(full_path); 717 pr_err("Opening device '%s' for client %s failed, failed to get device full path, err: %d\n", 718 open_msg->dev_name, srv_sess->sessname, ret); 719 goto reject; 720 } 721 722 bdev = blkdev_get_by_path(full_path, open_flags, THIS_MODULE, NULL); 723 if (IS_ERR(bdev)) { 724 ret = PTR_ERR(bdev); 725 pr_err("Opening device '%s' on session %s failed, failed to open the block device, err: %d\n", 726 full_path, srv_sess->sessname, ret); 727 goto free_path; 728 } 729 730 srv_dev = rnbd_srv_get_or_create_srv_dev(bdev, srv_sess, 731 open_msg->access_mode); 732 if (IS_ERR(srv_dev)) { 733 pr_err("Opening device '%s' on session %s failed, creating srv_dev failed, err: %ld\n", 734 full_path, srv_sess->sessname, PTR_ERR(srv_dev)); 735 ret = PTR_ERR(srv_dev); 736 goto blkdev_put; 737 } 738 739 srv_sess_dev = rnbd_srv_create_set_sess_dev(srv_sess, open_msg, 740 bdev, open_flags, 741 srv_dev); 742 if (IS_ERR(srv_sess_dev)) { 743 pr_err("Opening device '%s' on session %s failed, creating sess_dev failed, err: %ld\n", 744 full_path, srv_sess->sessname, PTR_ERR(srv_sess_dev)); 745 ret = PTR_ERR(srv_sess_dev); 746 goto srv_dev_put; 747 } 748 749 /* Create the srv_dev sysfs files if they haven't been created yet. The 750 * reason to delay the creation is not to create the sysfs files before 751 * we are sure the device can be opened. 752 */ 753 mutex_lock(&srv_dev->lock); 754 if (!srv_dev->dev_kobj.state_in_sysfs) { 755 ret = rnbd_srv_create_dev_sysfs(srv_dev, bdev); 756 if (ret) { 757 mutex_unlock(&srv_dev->lock); 758 rnbd_srv_err(srv_sess_dev, 759 "Opening device failed, failed to create device sysfs files, err: %d\n", 760 ret); 761 goto free_srv_sess_dev; 762 } 763 } 764 765 ret = rnbd_srv_create_dev_session_sysfs(srv_sess_dev); 766 if (ret) { 767 mutex_unlock(&srv_dev->lock); 768 rnbd_srv_err(srv_sess_dev, 769 "Opening device failed, failed to create dev client sysfs files, err: %d\n", 770 ret); 771 goto free_srv_sess_dev; 772 } 773 774 list_add(&srv_sess_dev->dev_list, &srv_dev->sess_dev_list); 775 mutex_unlock(&srv_dev->lock); 776 777 rnbd_srv_info(srv_sess_dev, "Opened device '%s'\n", srv_dev->id); 778 779 kfree(full_path); 780 781 fill_response: 782 rnbd_srv_fill_msg_open_rsp(rsp, srv_sess_dev); 783 mutex_unlock(&srv_sess->lock); 784 return 0; 785 786 free_srv_sess_dev: 787 xa_erase(&srv_sess->index_idr, srv_sess_dev->device_id); 788 synchronize_rcu(); 789 kfree(srv_sess_dev); 790 srv_dev_put: 791 if (open_msg->access_mode != RNBD_ACCESS_RO) { 792 mutex_lock(&srv_dev->lock); 793 srv_dev->open_write_cnt--; 794 mutex_unlock(&srv_dev->lock); 795 } 796 rnbd_put_srv_dev(srv_dev); 797 blkdev_put: 798 blkdev_put(bdev, open_flags); 799 free_path: 800 kfree(full_path); 801 reject: 802 mutex_unlock(&srv_sess->lock); 803 return ret; 804 } 805 806 static struct rtrs_srv_ctx *rtrs_ctx; 807 808 static struct rtrs_srv_ops rtrs_ops; 809 static int __init rnbd_srv_init_module(void) 810 { 811 int err; 812 813 BUILD_BUG_ON(sizeof(struct rnbd_msg_hdr) != 4); 814 BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info) != 36); 815 BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info_rsp) != 36); 816 BUILD_BUG_ON(sizeof(struct rnbd_msg_open) != 264); 817 BUILD_BUG_ON(sizeof(struct rnbd_msg_close) != 8); 818 BUILD_BUG_ON(sizeof(struct rnbd_msg_open_rsp) != 56); 819 rtrs_ops = (struct rtrs_srv_ops) { 820 .rdma_ev = rnbd_srv_rdma_ev, 821 .link_ev = rnbd_srv_link_ev, 822 }; 823 rtrs_ctx = rtrs_srv_open(&rtrs_ops, port_nr); 824 if (IS_ERR(rtrs_ctx)) { 825 err = PTR_ERR(rtrs_ctx); 826 pr_err("rtrs_srv_open(), err: %d\n", err); 827 return err; 828 } 829 830 err = rnbd_srv_create_sysfs_files(); 831 if (err) { 832 pr_err("rnbd_srv_create_sysfs_files(), err: %d\n", err); 833 rtrs_srv_close(rtrs_ctx); 834 return err; 835 } 836 837 return 0; 838 } 839 840 static void __exit rnbd_srv_cleanup_module(void) 841 { 842 rtrs_srv_close(rtrs_ctx); 843 WARN_ON(!list_empty(&sess_list)); 844 rnbd_srv_destroy_sysfs_files(); 845 } 846 847 module_init(rnbd_srv_init_module); 848 module_exit(rnbd_srv_cleanup_module); 849