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, struct rtrs_srv_op *id, 363 void *data, size_t datalen, 364 const void *usr, size_t usrlen) 365 { 366 struct rnbd_srv_session *srv_sess = priv; 367 const struct rnbd_msg_hdr *hdr = usr; 368 int ret = 0; 369 u16 type; 370 371 if (WARN_ON_ONCE(!srv_sess)) 372 return -ENODEV; 373 374 type = le16_to_cpu(hdr->type); 375 376 switch (type) { 377 case RNBD_MSG_IO: 378 return process_rdma(srv_sess, id, data, datalen, usr, usrlen); 379 case RNBD_MSG_CLOSE: 380 ret = process_msg_close(srv_sess, data, datalen, usr, usrlen); 381 break; 382 case RNBD_MSG_OPEN: 383 ret = process_msg_open(srv_sess, usr, usrlen, data, datalen); 384 break; 385 case RNBD_MSG_SESS_INFO: 386 ret = process_msg_sess_info(srv_sess, usr, usrlen, data, 387 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 rtrs_srv_resp_rdma(id, ret); 396 return 0; 397 } 398 399 static struct rnbd_srv_sess_dev 400 *rnbd_sess_dev_alloc(struct rnbd_srv_session *srv_sess) 401 { 402 struct rnbd_srv_sess_dev *sess_dev; 403 int error; 404 405 sess_dev = kzalloc(sizeof(*sess_dev), GFP_KERNEL); 406 if (!sess_dev) 407 return ERR_PTR(-ENOMEM); 408 409 error = xa_alloc(&srv_sess->index_idr, &sess_dev->device_id, sess_dev, 410 xa_limit_32b, GFP_NOWAIT); 411 if (error < 0) { 412 pr_warn("Allocating idr failed, err: %d\n", error); 413 kfree(sess_dev); 414 return ERR_PTR(error); 415 } 416 417 return sess_dev; 418 } 419 420 static struct rnbd_srv_dev *rnbd_srv_init_srv_dev(struct block_device *bdev) 421 { 422 struct rnbd_srv_dev *dev; 423 424 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 425 if (!dev) 426 return ERR_PTR(-ENOMEM); 427 428 snprintf(dev->id, sizeof(dev->id), "%pg", bdev); 429 kref_init(&dev->kref); 430 INIT_LIST_HEAD(&dev->sess_dev_list); 431 mutex_init(&dev->lock); 432 433 return dev; 434 } 435 436 static struct rnbd_srv_dev * 437 rnbd_srv_find_or_add_srv_dev(struct rnbd_srv_dev *new_dev) 438 { 439 struct rnbd_srv_dev *dev; 440 441 spin_lock(&dev_lock); 442 list_for_each_entry(dev, &dev_list, list) { 443 if (!strncmp(dev->id, new_dev->id, sizeof(dev->id))) { 444 if (!kref_get_unless_zero(&dev->kref)) 445 /* 446 * We lost the race, device is almost dead. 447 * Continue traversing to find a valid one. 448 */ 449 continue; 450 spin_unlock(&dev_lock); 451 return dev; 452 } 453 } 454 list_add(&new_dev->list, &dev_list); 455 spin_unlock(&dev_lock); 456 457 return new_dev; 458 } 459 460 static int rnbd_srv_check_update_open_perm(struct rnbd_srv_dev *srv_dev, 461 struct rnbd_srv_session *srv_sess, 462 enum rnbd_access_mode access_mode) 463 { 464 int ret = -EPERM; 465 466 mutex_lock(&srv_dev->lock); 467 468 switch (access_mode) { 469 case RNBD_ACCESS_RO: 470 ret = 0; 471 break; 472 case RNBD_ACCESS_RW: 473 if (srv_dev->open_write_cnt == 0) { 474 srv_dev->open_write_cnt++; 475 ret = 0; 476 } else { 477 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", 478 srv_dev->id, srv_sess->sessname, 479 srv_dev->open_write_cnt, 480 rnbd_access_mode_str(access_mode)); 481 } 482 break; 483 case RNBD_ACCESS_MIGRATION: 484 if (srv_dev->open_write_cnt < 2) { 485 srv_dev->open_write_cnt++; 486 ret = 0; 487 } else { 488 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", 489 srv_dev->id, srv_sess->sessname, 490 srv_dev->open_write_cnt, 491 rnbd_access_mode_str(access_mode)); 492 } 493 break; 494 default: 495 pr_err("Received mapping request for device '%s' on session %s with invalid access mode: %d\n", 496 srv_dev->id, srv_sess->sessname, access_mode); 497 ret = -EINVAL; 498 } 499 500 mutex_unlock(&srv_dev->lock); 501 502 return ret; 503 } 504 505 static struct rnbd_srv_dev * 506 rnbd_srv_get_or_create_srv_dev(struct rnbd_dev *rnbd_dev, 507 struct rnbd_srv_session *srv_sess, 508 enum rnbd_access_mode access_mode) 509 { 510 int ret; 511 struct rnbd_srv_dev *new_dev, *dev; 512 513 new_dev = rnbd_srv_init_srv_dev(rnbd_dev->bdev); 514 if (IS_ERR(new_dev)) 515 return new_dev; 516 517 dev = rnbd_srv_find_or_add_srv_dev(new_dev); 518 if (dev != new_dev) 519 kfree(new_dev); 520 521 ret = rnbd_srv_check_update_open_perm(dev, srv_sess, access_mode); 522 if (ret) { 523 rnbd_put_srv_dev(dev); 524 return ERR_PTR(ret); 525 } 526 527 return dev; 528 } 529 530 static void rnbd_srv_fill_msg_open_rsp(struct rnbd_msg_open_rsp *rsp, 531 struct rnbd_srv_sess_dev *sess_dev) 532 { 533 struct rnbd_dev *rnbd_dev = sess_dev->rnbd_dev; 534 535 rsp->hdr.type = cpu_to_le16(RNBD_MSG_OPEN_RSP); 536 rsp->device_id = 537 cpu_to_le32(sess_dev->device_id); 538 rsp->nsectors = 539 cpu_to_le64(get_capacity(rnbd_dev->bdev->bd_disk)); 540 rsp->logical_block_size = 541 cpu_to_le16(bdev_logical_block_size(rnbd_dev->bdev)); 542 rsp->physical_block_size = 543 cpu_to_le16(bdev_physical_block_size(rnbd_dev->bdev)); 544 rsp->max_segments = 545 cpu_to_le16(rnbd_dev_get_max_segs(rnbd_dev)); 546 rsp->max_hw_sectors = 547 cpu_to_le32(rnbd_dev_get_max_hw_sects(rnbd_dev)); 548 rsp->max_write_same_sectors = 0; 549 rsp->max_discard_sectors = 550 cpu_to_le32(rnbd_dev_get_max_discard_sects(rnbd_dev)); 551 rsp->discard_granularity = 552 cpu_to_le32(rnbd_dev_get_discard_granularity(rnbd_dev)); 553 rsp->discard_alignment = 554 cpu_to_le32(rnbd_dev_get_discard_alignment(rnbd_dev)); 555 rsp->secure_discard = 556 cpu_to_le16(rnbd_dev_get_secure_discard(rnbd_dev)); 557 rsp->cache_policy = 0; 558 if (bdev_write_cache(rnbd_dev->bdev)) 559 rsp->cache_policy |= RNBD_WRITEBACK; 560 if (bdev_fua(rnbd_dev->bdev)) 561 rsp->cache_policy |= RNBD_FUA; 562 } 563 564 static struct rnbd_srv_sess_dev * 565 rnbd_srv_create_set_sess_dev(struct rnbd_srv_session *srv_sess, 566 const struct rnbd_msg_open *open_msg, 567 struct rnbd_dev *rnbd_dev, fmode_t open_flags, 568 struct rnbd_srv_dev *srv_dev) 569 { 570 struct rnbd_srv_sess_dev *sdev = rnbd_sess_dev_alloc(srv_sess); 571 572 if (IS_ERR(sdev)) 573 return sdev; 574 575 kref_init(&sdev->kref); 576 577 strscpy(sdev->pathname, open_msg->dev_name, sizeof(sdev->pathname)); 578 579 sdev->rnbd_dev = rnbd_dev; 580 sdev->sess = srv_sess; 581 sdev->dev = srv_dev; 582 sdev->open_flags = open_flags; 583 sdev->access_mode = open_msg->access_mode; 584 585 return sdev; 586 } 587 588 static char *rnbd_srv_get_full_path(struct rnbd_srv_session *srv_sess, 589 const char *dev_name) 590 { 591 char *full_path; 592 char *a, *b; 593 594 full_path = kmalloc(PATH_MAX, GFP_KERNEL); 595 if (!full_path) 596 return ERR_PTR(-ENOMEM); 597 598 /* 599 * Replace %SESSNAME% with a real session name in order to 600 * create device namespace. 601 */ 602 a = strnstr(dev_search_path, "%SESSNAME%", sizeof(dev_search_path)); 603 if (a) { 604 int len = a - dev_search_path; 605 606 len = snprintf(full_path, PATH_MAX, "%.*s/%s/%s", len, 607 dev_search_path, srv_sess->sessname, dev_name); 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 } else { 615 snprintf(full_path, PATH_MAX, "%s/%s", 616 dev_search_path, dev_name); 617 } 618 619 /* eliminitate duplicated slashes */ 620 a = strchr(full_path, '/'); 621 b = a; 622 while (*b != '\0') { 623 if (*b == '/' && *a == '/') { 624 b++; 625 } else { 626 a++; 627 *a = *b; 628 b++; 629 } 630 } 631 a++; 632 *a = '\0'; 633 634 return full_path; 635 } 636 637 static int process_msg_sess_info(struct rnbd_srv_session *srv_sess, 638 const void *msg, size_t len, 639 void *data, size_t datalen) 640 { 641 const struct rnbd_msg_sess_info *sess_info_msg = msg; 642 struct rnbd_msg_sess_info_rsp *rsp = data; 643 644 srv_sess->ver = min_t(u8, sess_info_msg->ver, RNBD_PROTO_VER_MAJOR); 645 pr_debug("Session %s using protocol version %d (client version: %d, server version: %d)\n", 646 srv_sess->sessname, srv_sess->ver, 647 sess_info_msg->ver, RNBD_PROTO_VER_MAJOR); 648 649 rsp->hdr.type = cpu_to_le16(RNBD_MSG_SESS_INFO_RSP); 650 rsp->ver = srv_sess->ver; 651 652 return 0; 653 } 654 655 /** 656 * find_srv_sess_dev() - a dev is already opened by this name 657 * @srv_sess: the session to search. 658 * @dev_name: string containing the name of the device. 659 * 660 * Return struct rnbd_srv_sess_dev if srv_sess already opened the dev_name 661 * NULL if the session didn't open the device yet. 662 */ 663 static struct rnbd_srv_sess_dev * 664 find_srv_sess_dev(struct rnbd_srv_session *srv_sess, const char *dev_name) 665 { 666 struct rnbd_srv_sess_dev *sess_dev; 667 unsigned long index; 668 669 if (xa_empty(&srv_sess->index_idr)) 670 return NULL; 671 672 xa_for_each(&srv_sess->index_idr, index, sess_dev) 673 if (!strcmp(sess_dev->pathname, dev_name)) 674 return sess_dev; 675 676 return NULL; 677 } 678 679 static int process_msg_open(struct rnbd_srv_session *srv_sess, 680 const void *msg, size_t len, 681 void *data, size_t datalen) 682 { 683 int ret; 684 struct rnbd_srv_dev *srv_dev; 685 struct rnbd_srv_sess_dev *srv_sess_dev; 686 const struct rnbd_msg_open *open_msg = msg; 687 fmode_t open_flags; 688 char *full_path; 689 struct rnbd_dev *rnbd_dev; 690 struct rnbd_msg_open_rsp *rsp = data; 691 692 pr_debug("Open message received: session='%s' path='%s' access_mode=%d\n", 693 srv_sess->sessname, open_msg->dev_name, 694 open_msg->access_mode); 695 open_flags = FMODE_READ; 696 if (open_msg->access_mode != RNBD_ACCESS_RO) 697 open_flags |= FMODE_WRITE; 698 699 mutex_lock(&srv_sess->lock); 700 701 srv_sess_dev = find_srv_sess_dev(srv_sess, open_msg->dev_name); 702 if (srv_sess_dev) 703 goto fill_response; 704 705 if ((strlen(dev_search_path) + strlen(open_msg->dev_name)) 706 >= PATH_MAX) { 707 pr_err("Opening device for session %s failed, device path too long. '%s/%s' is longer than PATH_MAX (%d)\n", 708 srv_sess->sessname, dev_search_path, open_msg->dev_name, 709 PATH_MAX); 710 ret = -EINVAL; 711 goto reject; 712 } 713 if (strstr(open_msg->dev_name, "..")) { 714 pr_err("Opening device for session %s failed, device path %s contains relative path ..\n", 715 srv_sess->sessname, open_msg->dev_name); 716 ret = -EINVAL; 717 goto reject; 718 } 719 full_path = rnbd_srv_get_full_path(srv_sess, open_msg->dev_name); 720 if (IS_ERR(full_path)) { 721 ret = PTR_ERR(full_path); 722 pr_err("Opening device '%s' for client %s failed, failed to get device full path, err: %d\n", 723 open_msg->dev_name, srv_sess->sessname, ret); 724 goto reject; 725 } 726 727 rnbd_dev = rnbd_dev_open(full_path, open_flags); 728 if (IS_ERR(rnbd_dev)) { 729 pr_err("Opening device '%s' on session %s failed, failed to open the block device, err: %ld\n", 730 full_path, srv_sess->sessname, PTR_ERR(rnbd_dev)); 731 ret = PTR_ERR(rnbd_dev); 732 goto free_path; 733 } 734 735 srv_dev = rnbd_srv_get_or_create_srv_dev(rnbd_dev, srv_sess, 736 open_msg->access_mode); 737 if (IS_ERR(srv_dev)) { 738 pr_err("Opening device '%s' on session %s failed, creating srv_dev failed, err: %ld\n", 739 full_path, srv_sess->sessname, PTR_ERR(srv_dev)); 740 ret = PTR_ERR(srv_dev); 741 goto rnbd_dev_close; 742 } 743 744 srv_sess_dev = rnbd_srv_create_set_sess_dev(srv_sess, open_msg, 745 rnbd_dev, open_flags, 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: %ld\n", 749 full_path, srv_sess->sessname, PTR_ERR(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, rnbd_dev->bdev); 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->id); 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 rnbd_dev_close: 803 rnbd_dev_close(rnbd_dev); 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; 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 err = PTR_ERR(rtrs_ctx); 831 pr_err("rtrs_srv_open(), err: %d\n", err); 832 return err; 833 } 834 835 err = rnbd_srv_create_sysfs_files(); 836 if (err) { 837 pr_err("rnbd_srv_create_sysfs_files(), err: %d\n", err); 838 rtrs_srv_close(rtrs_ctx); 839 return err; 840 } 841 842 return 0; 843 } 844 845 static void __exit rnbd_srv_cleanup_module(void) 846 { 847 rtrs_srv_close(rtrs_ctx); 848 WARN_ON(!list_empty(&sess_list)); 849 rnbd_srv_destroy_sysfs_files(); 850 } 851 852 module_init(rnbd_srv_init_module); 853 module_exit(rnbd_srv_cleanup_module); 854