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: %pe\n", 140 srv_sess->sessname, dev_id, sess_dev); 141 err = -ENOTCONN; 142 goto err; 143 } 144 145 priv->sess_dev = sess_dev; 146 priv->id = id; 147 148 bio = bio_alloc(file_bdev(sess_dev->bdev_file), 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_rl(sess_dev, "Failed to map data to bio\n"); 153 err = -EINVAL; 154 goto bio_put; 155 } 156 157 bio->bi_opf = rnbd_to_bio_flags(le32_to_cpu(msg->rw)); 158 if (bio_has_data(bio) && 159 bio->bi_iter.bi_size != le32_to_cpu(msg->bi_size)) { 160 rnbd_srv_err_rl(sess_dev, "Datalen mismatch: bio bi_size (%u), bi_size (%u)\n", 161 bio->bi_iter.bi_size, msg->bi_size); 162 err = -EINVAL; 163 goto bio_put; 164 } 165 bio->bi_end_io = rnbd_dev_bi_end_io; 166 bio->bi_private = priv; 167 bio->bi_iter.bi_sector = le64_to_cpu(msg->sector); 168 prio = srv_sess->ver < RNBD_PROTO_VER_MAJOR || 169 usrlen < sizeof(*msg) ? 0 : le16_to_cpu(msg->prio); 170 bio_set_prio(bio, prio); 171 172 submit_bio(bio); 173 174 return 0; 175 176 bio_put: 177 bio_put(bio); 178 rnbd_put_sess_dev(sess_dev); 179 err: 180 kfree(priv); 181 return err; 182 } 183 184 static void destroy_device(struct kref *kref) 185 { 186 struct rnbd_srv_dev *dev = container_of(kref, struct rnbd_srv_dev, kref); 187 188 WARN_ONCE(!list_empty(&dev->sess_dev_list), 189 "Device %s is being destroyed but still in use!\n", 190 dev->name); 191 192 spin_lock(&dev_lock); 193 list_del(&dev->list); 194 spin_unlock(&dev_lock); 195 196 mutex_destroy(&dev->lock); 197 if (dev->dev_kobj.state_in_sysfs) 198 /* 199 * Destroy kobj only if it was really created. 200 */ 201 rnbd_srv_destroy_dev_sysfs(dev); 202 else 203 kfree(dev); 204 } 205 206 static void rnbd_put_srv_dev(struct rnbd_srv_dev *dev) 207 { 208 kref_put(&dev->kref, destroy_device); 209 } 210 211 void rnbd_destroy_sess_dev(struct rnbd_srv_sess_dev *sess_dev, bool keep_id) 212 { 213 DECLARE_COMPLETION_ONSTACK(dc); 214 215 if (keep_id) 216 /* free the resources for the id but don't */ 217 /* allow to re-use the id itself because it */ 218 /* is still used by the client */ 219 xa_cmpxchg(&sess_dev->sess->index_idr, sess_dev->device_id, 220 sess_dev, NULL, 0); 221 else 222 xa_erase(&sess_dev->sess->index_idr, sess_dev->device_id); 223 synchronize_rcu(); 224 225 sess_dev->destroy_comp = &dc; 226 rnbd_put_sess_dev(sess_dev); 227 wait_for_completion(&dc); /* wait for inflights to drop to zero */ 228 229 fput(sess_dev->bdev_file); 230 mutex_lock(&sess_dev->dev->lock); 231 list_del(&sess_dev->dev_list); 232 if (!sess_dev->readonly) 233 sess_dev->dev->open_write_cnt--; 234 mutex_unlock(&sess_dev->dev->lock); 235 236 rnbd_put_srv_dev(sess_dev->dev); 237 238 rnbd_srv_info(sess_dev, "Device closed\n"); 239 kfree(sess_dev); 240 } 241 242 static void destroy_sess(struct rnbd_srv_session *srv_sess) 243 { 244 struct rnbd_srv_sess_dev *sess_dev; 245 unsigned long index; 246 247 if (xa_empty(&srv_sess->index_idr)) 248 goto out; 249 250 trace_destroy_sess(srv_sess); 251 252 mutex_lock(&srv_sess->lock); 253 xa_for_each(&srv_sess->index_idr, index, sess_dev) 254 rnbd_srv_destroy_dev_session_sysfs(sess_dev); 255 mutex_unlock(&srv_sess->lock); 256 257 out: 258 xa_destroy(&srv_sess->index_idr); 259 260 pr_info("RTRS Session %s disconnected\n", srv_sess->sessname); 261 262 mutex_lock(&sess_lock); 263 list_del(&srv_sess->list); 264 mutex_unlock(&sess_lock); 265 266 mutex_destroy(&srv_sess->lock); 267 kfree(srv_sess); 268 } 269 270 static int create_sess(struct rtrs_srv_sess *rtrs) 271 { 272 struct rnbd_srv_session *srv_sess; 273 char pathname[NAME_MAX]; 274 int err; 275 276 err = rtrs_srv_get_path_name(rtrs, pathname, sizeof(pathname)); 277 if (err) { 278 pr_err("rtrs_srv_get_path_name(%s): %d\n", pathname, err); 279 280 return err; 281 } 282 srv_sess = kzalloc(sizeof(*srv_sess), GFP_KERNEL); 283 if (!srv_sess) 284 return -ENOMEM; 285 286 srv_sess->queue_depth = rtrs_srv_get_queue_depth(rtrs); 287 xa_init_flags(&srv_sess->index_idr, XA_FLAGS_ALLOC); 288 mutex_init(&srv_sess->lock); 289 mutex_lock(&sess_lock); 290 list_add(&srv_sess->list, &sess_list); 291 mutex_unlock(&sess_lock); 292 293 srv_sess->rtrs = rtrs; 294 strscpy(srv_sess->sessname, pathname, sizeof(srv_sess->sessname)); 295 296 rtrs_srv_set_sess_priv(rtrs, srv_sess); 297 298 trace_create_sess(srv_sess); 299 300 return 0; 301 } 302 303 static int rnbd_srv_link_ev(struct rtrs_srv_sess *rtrs, 304 enum rtrs_srv_link_ev ev, void *priv) 305 { 306 struct rnbd_srv_session *srv_sess = priv; 307 308 switch (ev) { 309 case RTRS_SRV_LINK_EV_CONNECTED: 310 return create_sess(rtrs); 311 312 case RTRS_SRV_LINK_EV_DISCONNECTED: 313 if (WARN_ON_ONCE(!srv_sess)) 314 return -EINVAL; 315 316 destroy_sess(srv_sess); 317 return 0; 318 319 default: 320 pr_warn("Received unknown RTRS session event %d from session %s\n", 321 ev, srv_sess->sessname); 322 return -EINVAL; 323 } 324 } 325 326 void rnbd_srv_sess_dev_force_close(struct rnbd_srv_sess_dev *sess_dev, 327 struct kobj_attribute *attr) 328 { 329 struct rnbd_srv_session *sess = sess_dev->sess; 330 331 /* It is already started to close by client's close message. */ 332 if (!mutex_trylock(&sess->lock)) 333 return; 334 335 sess_dev->keep_id = true; 336 /* first remove sysfs itself to avoid deadlock */ 337 sysfs_remove_file_self(&sess_dev->kobj, &attr->attr); 338 rnbd_srv_destroy_dev_session_sysfs(sess_dev); 339 mutex_unlock(&sess->lock); 340 } 341 342 static void process_msg_close(struct rnbd_srv_session *srv_sess, 343 void *data, size_t datalen, const void *usr, 344 size_t usrlen) 345 { 346 const struct rnbd_msg_close *close_msg = usr; 347 struct rnbd_srv_sess_dev *sess_dev; 348 349 trace_process_msg_close(srv_sess, close_msg); 350 351 sess_dev = rnbd_get_sess_dev(le32_to_cpu(close_msg->device_id), 352 srv_sess); 353 if (IS_ERR(sess_dev)) 354 return; 355 356 rnbd_put_sess_dev(sess_dev); 357 mutex_lock(&srv_sess->lock); 358 rnbd_srv_destroy_dev_session_sysfs(sess_dev); 359 mutex_unlock(&srv_sess->lock); 360 } 361 362 static int process_msg_open(struct rnbd_srv_session *srv_sess, 363 const void *msg, size_t len, 364 void *data, size_t datalen); 365 366 static void process_msg_sess_info(struct rnbd_srv_session *srv_sess, 367 const void *msg, size_t len, 368 void *data, size_t datalen); 369 370 static int rnbd_srv_rdma_ev(void *priv, struct rtrs_srv_op *id, 371 void *data, size_t datalen, 372 const void *usr, size_t usrlen) 373 { 374 struct rnbd_srv_session *srv_sess = priv; 375 const struct rnbd_msg_hdr *hdr = usr; 376 int ret = 0; 377 u16 type; 378 379 if (WARN_ON_ONCE(!srv_sess)) 380 return -ENODEV; 381 382 type = le16_to_cpu(hdr->type); 383 384 switch (type) { 385 case RNBD_MSG_IO: 386 return process_rdma(srv_sess, id, data, datalen, usr, usrlen); 387 case RNBD_MSG_CLOSE: 388 process_msg_close(srv_sess, data, datalen, usr, usrlen); 389 break; 390 case RNBD_MSG_OPEN: 391 ret = process_msg_open(srv_sess, usr, usrlen, data, datalen); 392 break; 393 case RNBD_MSG_SESS_INFO: 394 process_msg_sess_info(srv_sess, usr, usrlen, data, datalen); 395 break; 396 default: 397 pr_warn("Received unexpected message type %d from session %s\n", 398 type, srv_sess->sessname); 399 return -EINVAL; 400 } 401 402 /* 403 * Since ret is passed to rtrs to handle the failure case, we 404 * just return 0 at the end otherwise callers in rtrs would call 405 * send_io_resp_imm again to print redundant err message. 406 */ 407 rtrs_srv_resp_rdma(id, ret); 408 return 0; 409 } 410 411 static struct rnbd_srv_sess_dev 412 *rnbd_sess_dev_alloc(struct rnbd_srv_session *srv_sess) 413 { 414 struct rnbd_srv_sess_dev *sess_dev; 415 int error; 416 417 sess_dev = kzalloc(sizeof(*sess_dev), GFP_KERNEL); 418 if (!sess_dev) 419 return ERR_PTR(-ENOMEM); 420 421 error = xa_alloc(&srv_sess->index_idr, &sess_dev->device_id, sess_dev, 422 xa_limit_32b, GFP_NOWAIT); 423 if (error < 0) { 424 pr_warn("Allocating idr failed, err: %d\n", error); 425 kfree(sess_dev); 426 return ERR_PTR(error); 427 } 428 429 return sess_dev; 430 } 431 432 static struct rnbd_srv_dev *rnbd_srv_init_srv_dev(struct block_device *bdev) 433 { 434 struct rnbd_srv_dev *dev; 435 436 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 437 if (!dev) 438 return ERR_PTR(-ENOMEM); 439 440 snprintf(dev->name, sizeof(dev->name), "%pg", bdev); 441 kref_init(&dev->kref); 442 INIT_LIST_HEAD(&dev->sess_dev_list); 443 mutex_init(&dev->lock); 444 445 return dev; 446 } 447 448 static struct rnbd_srv_dev * 449 rnbd_srv_find_or_add_srv_dev(struct rnbd_srv_dev *new_dev) 450 { 451 struct rnbd_srv_dev *dev; 452 453 spin_lock(&dev_lock); 454 list_for_each_entry(dev, &dev_list, list) { 455 if (!strncmp(dev->name, new_dev->name, sizeof(dev->name))) { 456 if (!kref_get_unless_zero(&dev->kref)) 457 /* 458 * We lost the race, device is almost dead. 459 * Continue traversing to find a valid one. 460 */ 461 continue; 462 spin_unlock(&dev_lock); 463 return dev; 464 } 465 } 466 list_add(&new_dev->list, &dev_list); 467 spin_unlock(&dev_lock); 468 469 return new_dev; 470 } 471 472 static int rnbd_srv_check_update_open_perm(struct rnbd_srv_dev *srv_dev, 473 struct rnbd_srv_session *srv_sess, 474 enum rnbd_access_mode access_mode) 475 { 476 int ret = 0; 477 478 mutex_lock(&srv_dev->lock); 479 480 switch (access_mode) { 481 case RNBD_ACCESS_RO: 482 break; 483 case RNBD_ACCESS_RW: 484 if (srv_dev->open_write_cnt == 0) { 485 srv_dev->open_write_cnt++; 486 } else { 487 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", 488 srv_dev->name, srv_sess->sessname, 489 srv_dev->open_write_cnt, 490 rnbd_access_modes[access_mode].str); 491 ret = -EPERM; 492 } 493 break; 494 case RNBD_ACCESS_MIGRATION: 495 if (srv_dev->open_write_cnt < 2) { 496 srv_dev->open_write_cnt++; 497 } else { 498 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", 499 srv_dev->name, srv_sess->sessname, 500 srv_dev->open_write_cnt, 501 rnbd_access_modes[access_mode].str); 502 ret = -EPERM; 503 } 504 break; 505 default: 506 pr_err("Received mapping request for device '%s' on session %s with invalid access mode: %d\n", 507 srv_dev->name, srv_sess->sessname, access_mode); 508 ret = -EINVAL; 509 } 510 511 mutex_unlock(&srv_dev->lock); 512 513 return ret; 514 } 515 516 static struct rnbd_srv_dev * 517 rnbd_srv_get_or_create_srv_dev(struct block_device *bdev, 518 struct rnbd_srv_session *srv_sess, 519 enum rnbd_access_mode access_mode) 520 { 521 int ret; 522 struct rnbd_srv_dev *new_dev, *dev; 523 524 new_dev = rnbd_srv_init_srv_dev(bdev); 525 if (IS_ERR(new_dev)) 526 return new_dev; 527 528 dev = rnbd_srv_find_or_add_srv_dev(new_dev); 529 if (dev != new_dev) 530 kfree(new_dev); 531 532 ret = rnbd_srv_check_update_open_perm(dev, srv_sess, access_mode); 533 if (ret) { 534 rnbd_put_srv_dev(dev); 535 return ERR_PTR(ret); 536 } 537 538 return dev; 539 } 540 541 static void rnbd_srv_fill_msg_open_rsp(struct rnbd_msg_open_rsp *rsp, 542 struct rnbd_srv_sess_dev *sess_dev) 543 { 544 struct block_device *bdev = file_bdev(sess_dev->bdev_file); 545 546 rsp->hdr.type = cpu_to_le16(RNBD_MSG_OPEN_RSP); 547 rsp->device_id = cpu_to_le32(sess_dev->device_id); 548 rsp->nsectors = cpu_to_le64(bdev_nr_sectors(bdev)); 549 rsp->logical_block_size = cpu_to_le16(bdev_logical_block_size(bdev)); 550 rsp->physical_block_size = cpu_to_le16(bdev_physical_block_size(bdev)); 551 rsp->max_segments = cpu_to_le16(bdev_max_segments(bdev)); 552 rsp->max_hw_sectors = 553 cpu_to_le32(queue_max_hw_sectors(bdev_get_queue(bdev))); 554 rsp->max_write_zeroes_sectors = 555 cpu_to_le32(bdev_write_zeroes_sectors(bdev)); 556 rsp->max_discard_sectors = cpu_to_le32(bdev_max_discard_sectors(bdev)); 557 rsp->discard_granularity = cpu_to_le32(bdev_discard_granularity(bdev)); 558 rsp->discard_alignment = cpu_to_le32(bdev_discard_alignment(bdev)); 559 rsp->secure_discard = cpu_to_le16(bdev_max_secure_erase_sectors(bdev)); 560 rsp->cache_policy = 0; 561 if (bdev_write_cache(bdev)) 562 rsp->cache_policy |= RNBD_WRITEBACK; 563 if (bdev_fua(bdev)) 564 rsp->cache_policy |= RNBD_FUA; 565 } 566 567 static struct rnbd_srv_sess_dev * 568 rnbd_srv_create_set_sess_dev(struct rnbd_srv_session *srv_sess, 569 const struct rnbd_msg_open *open_msg, 570 struct file *bdev_file, bool readonly, 571 struct rnbd_srv_dev *srv_dev) 572 { 573 struct rnbd_srv_sess_dev *sdev = rnbd_sess_dev_alloc(srv_sess); 574 575 if (IS_ERR(sdev)) 576 return sdev; 577 578 kref_init(&sdev->kref); 579 580 strscpy(sdev->pathname, open_msg->dev_name, sizeof(sdev->pathname)); 581 582 sdev->bdev_file = bdev_file; 583 sdev->sess = srv_sess; 584 sdev->dev = srv_dev; 585 sdev->readonly = readonly; 586 sdev->access_mode = open_msg->access_mode; 587 588 return sdev; 589 } 590 591 static char *rnbd_srv_get_full_path(struct rnbd_srv_session *srv_sess, 592 const char *dev_name) 593 { 594 char *full_path; 595 char *a, *b; 596 int len; 597 598 full_path = kmalloc(PATH_MAX, GFP_KERNEL); 599 if (!full_path) 600 return ERR_PTR(-ENOMEM); 601 602 /* 603 * Replace %SESSNAME% with a real session name in order to 604 * create device namespace. 605 */ 606 a = strnstr(dev_search_path, "%SESSNAME%", sizeof(dev_search_path)); 607 if (a) { 608 len = a - dev_search_path; 609 610 len = snprintf(full_path, PATH_MAX, "%.*s/%s/%s", len, 611 dev_search_path, srv_sess->sessname, dev_name); 612 } else { 613 len = snprintf(full_path, PATH_MAX, "%s/%s", 614 dev_search_path, dev_name); 615 } 616 if (len >= PATH_MAX) { 617 pr_err("Too long path: %s, %s, %s\n", 618 dev_search_path, srv_sess->sessname, dev_name); 619 kfree(full_path); 620 return ERR_PTR(-EINVAL); 621 } 622 623 /* eliminitate duplicated slashes */ 624 a = strchr(full_path, '/'); 625 b = a; 626 while (*b != '\0') { 627 if (*b == '/' && *a == '/') { 628 b++; 629 } else { 630 a++; 631 *a = *b; 632 b++; 633 } 634 } 635 a++; 636 *a = '\0'; 637 638 return full_path; 639 } 640 641 static void process_msg_sess_info(struct rnbd_srv_session *srv_sess, 642 const void *msg, size_t len, 643 void *data, size_t datalen) 644 { 645 const struct rnbd_msg_sess_info *sess_info_msg = msg; 646 struct rnbd_msg_sess_info_rsp *rsp = data; 647 648 srv_sess->ver = min_t(u8, sess_info_msg->ver, RNBD_PROTO_VER_MAJOR); 649 650 trace_process_msg_sess_info(srv_sess, sess_info_msg); 651 652 rsp->hdr.type = cpu_to_le16(RNBD_MSG_SESS_INFO_RSP); 653 rsp->ver = srv_sess->ver; 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 struct file *bdev_file; 689 blk_mode_t open_flags = BLK_OPEN_READ; 690 char *full_path; 691 struct rnbd_msg_open_rsp *rsp = data; 692 693 trace_process_msg_open(srv_sess, open_msg); 694 695 if (open_msg->access_mode != RNBD_ACCESS_RO) 696 open_flags |= BLK_OPEN_WRITE; 697 698 mutex_lock(&srv_sess->lock); 699 700 srv_sess_dev = find_srv_sess_dev(srv_sess, open_msg->dev_name); 701 if (srv_sess_dev) 702 goto fill_response; 703 704 if ((strlen(dev_search_path) + strlen(open_msg->dev_name)) 705 >= PATH_MAX) { 706 pr_err("Opening device for session %s failed, device path too long. '%s/%s' is longer than PATH_MAX (%d)\n", 707 srv_sess->sessname, dev_search_path, open_msg->dev_name, 708 PATH_MAX); 709 ret = -EINVAL; 710 goto reject; 711 } 712 if (strstr(open_msg->dev_name, "..")) { 713 pr_err("Opening device for session %s failed, device path %s contains relative path ..\n", 714 srv_sess->sessname, open_msg->dev_name); 715 ret = -EINVAL; 716 goto reject; 717 } 718 full_path = rnbd_srv_get_full_path(srv_sess, open_msg->dev_name); 719 if (IS_ERR(full_path)) { 720 ret = PTR_ERR(full_path); 721 pr_err("Opening device '%s' for client %s failed, failed to get device full path, err: %pe\n", 722 open_msg->dev_name, srv_sess->sessname, full_path); 723 goto reject; 724 } 725 726 bdev_file = bdev_file_open_by_path(full_path, open_flags, NULL, NULL); 727 if (IS_ERR(bdev_file)) { 728 ret = PTR_ERR(bdev_file); 729 pr_err("Opening device '%s' on session %s failed, failed to open the block device, err: %pe\n", 730 full_path, srv_sess->sessname, bdev_file); 731 goto free_path; 732 } 733 734 srv_dev = rnbd_srv_get_or_create_srv_dev(file_bdev(bdev_file), srv_sess, 735 open_msg->access_mode); 736 if (IS_ERR(srv_dev)) { 737 pr_err("Opening device '%s' on session %s failed, creating srv_dev failed, err: %pe\n", 738 full_path, srv_sess->sessname, srv_dev); 739 ret = PTR_ERR(srv_dev); 740 goto blkdev_put; 741 } 742 743 srv_sess_dev = rnbd_srv_create_set_sess_dev(srv_sess, open_msg, 744 bdev_file, 745 open_msg->access_mode == RNBD_ACCESS_RO, 746 srv_dev); 747 if (IS_ERR(srv_sess_dev)) { 748 pr_err("Opening device '%s' on session %s failed, creating sess_dev failed, err: %pe\n", 749 full_path, srv_sess->sessname, srv_sess_dev); 750 ret = PTR_ERR(srv_sess_dev); 751 goto srv_dev_put; 752 } 753 754 /* Create the srv_dev sysfs files if they haven't been created yet. The 755 * reason to delay the creation is not to create the sysfs files before 756 * we are sure the device can be opened. 757 */ 758 mutex_lock(&srv_dev->lock); 759 if (!srv_dev->dev_kobj.state_in_sysfs) { 760 ret = rnbd_srv_create_dev_sysfs(srv_dev, file_bdev(bdev_file)); 761 if (ret) { 762 mutex_unlock(&srv_dev->lock); 763 rnbd_srv_err(srv_sess_dev, 764 "Opening device failed, failed to create device sysfs files, err: %d\n", 765 ret); 766 goto free_srv_sess_dev; 767 } 768 } 769 770 ret = rnbd_srv_create_dev_session_sysfs(srv_sess_dev); 771 if (ret) { 772 mutex_unlock(&srv_dev->lock); 773 rnbd_srv_err(srv_sess_dev, 774 "Opening device failed, failed to create dev client sysfs files, err: %d\n", 775 ret); 776 goto free_srv_sess_dev; 777 } 778 779 list_add(&srv_sess_dev->dev_list, &srv_dev->sess_dev_list); 780 mutex_unlock(&srv_dev->lock); 781 782 rnbd_srv_info(srv_sess_dev, "Opened device '%s'\n", srv_dev->name); 783 784 kfree(full_path); 785 786 fill_response: 787 rnbd_srv_fill_msg_open_rsp(rsp, srv_sess_dev); 788 mutex_unlock(&srv_sess->lock); 789 return 0; 790 791 free_srv_sess_dev: 792 xa_erase(&srv_sess->index_idr, srv_sess_dev->device_id); 793 synchronize_rcu(); 794 kfree(srv_sess_dev); 795 srv_dev_put: 796 if (open_msg->access_mode != RNBD_ACCESS_RO) { 797 mutex_lock(&srv_dev->lock); 798 srv_dev->open_write_cnt--; 799 mutex_unlock(&srv_dev->lock); 800 } 801 rnbd_put_srv_dev(srv_dev); 802 blkdev_put: 803 fput(bdev_file); 804 free_path: 805 kfree(full_path); 806 reject: 807 mutex_unlock(&srv_sess->lock); 808 return ret; 809 } 810 811 static struct rtrs_srv_ctx *rtrs_ctx; 812 813 static struct rtrs_srv_ops rtrs_ops; 814 static int __init rnbd_srv_init_module(void) 815 { 816 int err = 0; 817 818 BUILD_BUG_ON(sizeof(struct rnbd_msg_hdr) != 4); 819 BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info) != 36); 820 BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info_rsp) != 36); 821 BUILD_BUG_ON(sizeof(struct rnbd_msg_open) != 264); 822 BUILD_BUG_ON(sizeof(struct rnbd_msg_close) != 8); 823 BUILD_BUG_ON(sizeof(struct rnbd_msg_open_rsp) != 56); 824 rtrs_ops = (struct rtrs_srv_ops) { 825 .rdma_ev = rnbd_srv_rdma_ev, 826 .link_ev = rnbd_srv_link_ev, 827 }; 828 rtrs_ctx = rtrs_srv_open(&rtrs_ops, port_nr); 829 if (IS_ERR(rtrs_ctx)) { 830 pr_err("rtrs_srv_open(), err: %pe\n", rtrs_ctx); 831 return PTR_ERR(rtrs_ctx); 832 } 833 834 err = rnbd_srv_create_sysfs_files(); 835 if (err) { 836 pr_err("rnbd_srv_create_sysfs_files(), err: %d\n", err); 837 rtrs_srv_close(rtrs_ctx); 838 } 839 840 return err; 841 } 842 843 static void __exit rnbd_srv_cleanup_module(void) 844 { 845 rtrs_srv_close(rtrs_ctx); 846 WARN_ON(!list_empty(&sess_list)); 847 rnbd_srv_destroy_sysfs_files(); 848 } 849 850 module_init(rnbd_srv_init_module); 851 module_exit(rnbd_srv_cleanup_module); 852