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 #include "rnbd-srv-trace.h" 18 19 MODULE_DESCRIPTION("RDMA Network Block Device Server"); 20 MODULE_LICENSE("GPL"); 21 22 static u16 port_nr = RTRS_PORT; 23 24 module_param_named(port_nr, port_nr, ushort, 0444); 25 MODULE_PARM_DESC(port_nr, 26 "The port number the server is listening on (default: " 27 __stringify(RTRS_PORT)")"); 28 29 #define DEFAULT_DEV_SEARCH_PATH "/" 30 31 static char dev_search_path[PATH_MAX] = DEFAULT_DEV_SEARCH_PATH; 32 33 static int dev_search_path_set(const char *val, const struct kernel_param *kp) 34 { 35 const char *p = strrchr(val, '\n') ? : val + strlen(val); 36 37 if (strlen(val) >= sizeof(dev_search_path)) 38 return -EINVAL; 39 40 snprintf(dev_search_path, sizeof(dev_search_path), "%.*s", 41 (int)(p - val), val); 42 43 pr_info("dev_search_path changed to '%s'\n", dev_search_path); 44 45 return 0; 46 } 47 48 static struct kparam_string dev_search_path_kparam_str = { 49 .maxlen = sizeof(dev_search_path), 50 .string = dev_search_path 51 }; 52 53 static const struct kernel_param_ops dev_search_path_ops = { 54 .set = dev_search_path_set, 55 .get = param_get_string, 56 }; 57 58 module_param_cb(dev_search_path, &dev_search_path_ops, 59 &dev_search_path_kparam_str, 0444); 60 MODULE_PARM_DESC(dev_search_path, 61 "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: " 62 DEFAULT_DEV_SEARCH_PATH ")"); 63 64 static DEFINE_MUTEX(sess_lock); 65 static DEFINE_SPINLOCK(dev_lock); 66 67 static LIST_HEAD(sess_list); 68 static LIST_HEAD(dev_list); 69 70 struct rnbd_io_private { 71 struct rtrs_srv_op *id; 72 struct rnbd_srv_sess_dev *sess_dev; 73 }; 74 75 static void rnbd_sess_dev_release(struct kref *kref) 76 { 77 struct rnbd_srv_sess_dev *sess_dev; 78 79 sess_dev = container_of(kref, struct rnbd_srv_sess_dev, kref); 80 complete(sess_dev->destroy_comp); 81 } 82 83 static inline void rnbd_put_sess_dev(struct rnbd_srv_sess_dev *sess_dev) 84 { 85 kref_put(&sess_dev->kref, rnbd_sess_dev_release); 86 } 87 88 void rnbd_endio(void *priv, int error) 89 { 90 struct rnbd_io_private *rnbd_priv = priv; 91 struct rnbd_srv_sess_dev *sess_dev = rnbd_priv->sess_dev; 92 93 rnbd_put_sess_dev(sess_dev); 94 95 rtrs_srv_resp_rdma(rnbd_priv->id, error); 96 97 kfree(priv); 98 } 99 100 static struct rnbd_srv_sess_dev * 101 rnbd_get_sess_dev(int dev_id, struct rnbd_srv_session *srv_sess) 102 { 103 struct rnbd_srv_sess_dev *sess_dev; 104 int ret = 0; 105 106 rcu_read_lock(); 107 sess_dev = xa_load(&srv_sess->index_idr, dev_id); 108 if (sess_dev) 109 ret = kref_get_unless_zero(&sess_dev->kref); 110 rcu_read_unlock(); 111 112 if (!sess_dev || !ret) 113 return ERR_PTR(-ENXIO); 114 115 return sess_dev; 116 } 117 118 static void rnbd_dev_bi_end_io(struct bio *bio) 119 { 120 rnbd_endio(bio->bi_private, blk_status_to_errno(bio->bi_status)); 121 bio_put(bio); 122 } 123 124 static int process_rdma(struct rnbd_srv_session *srv_sess, 125 struct rtrs_srv_op *id, void *data, u32 datalen, 126 const void *usr, size_t usrlen) 127 { 128 const struct rnbd_msg_io *msg = usr; 129 struct rnbd_io_private *priv; 130 struct rnbd_srv_sess_dev *sess_dev; 131 u32 dev_id; 132 int err; 133 struct bio *bio; 134 short prio; 135 136 trace_process_rdma(srv_sess, msg, id, datalen, usrlen); 137 138 priv = kmalloc(sizeof(*priv), GFP_KERNEL); 139 if (!priv) 140 return -ENOMEM; 141 142 dev_id = le32_to_cpu(msg->device_id); 143 144 sess_dev = rnbd_get_sess_dev(dev_id, srv_sess); 145 if (IS_ERR(sess_dev)) { 146 pr_err_ratelimited("Got I/O request on session %s for unknown device id %d\n", 147 srv_sess->sessname, dev_id); 148 err = -ENOTCONN; 149 goto err; 150 } 151 152 priv->sess_dev = sess_dev; 153 priv->id = id; 154 155 bio = bio_alloc(sess_dev->rnbd_dev->bdev, 1, 156 rnbd_to_bio_flags(le32_to_cpu(msg->rw)), GFP_KERNEL); 157 if (bio_add_page(bio, virt_to_page(data), datalen, 158 offset_in_page(data)) != datalen) { 159 rnbd_srv_err(sess_dev, "Failed to map data to bio\n"); 160 err = -EINVAL; 161 goto bio_put; 162 } 163 164 bio->bi_end_io = rnbd_dev_bi_end_io; 165 bio->bi_private = priv; 166 bio->bi_iter.bi_sector = le64_to_cpu(msg->sector); 167 bio->bi_iter.bi_size = le32_to_cpu(msg->bi_size); 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->id); 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 rnbd_dev_close(sess_dev->rnbd_dev); 230 mutex_lock(&sess_dev->dev->lock); 231 list_del(&sess_dev->dev_list); 232 if (sess_dev->open_flags & FMODE_WRITE) 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 int 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, 371 struct rtrs_srv_op *id, int dir, 372 void *data, size_t datalen, const void *usr, 373 size_t usrlen) 374 { 375 struct rnbd_srv_session *srv_sess = priv; 376 const struct rnbd_msg_hdr *hdr = usr; 377 int ret = 0; 378 u16 type; 379 380 if (WARN_ON_ONCE(!srv_sess)) 381 return -ENODEV; 382 383 type = le16_to_cpu(hdr->type); 384 385 switch (type) { 386 case RNBD_MSG_IO: 387 return process_rdma(srv_sess, id, data, datalen, usr, usrlen); 388 case RNBD_MSG_CLOSE: 389 process_msg_close(srv_sess, data, datalen, usr, usrlen); 390 break; 391 case RNBD_MSG_OPEN: 392 ret = process_msg_open(srv_sess, usr, usrlen, data, datalen); 393 break; 394 case RNBD_MSG_SESS_INFO: 395 ret = process_msg_sess_info(srv_sess, usr, usrlen, data, 396 datalen); 397 break; 398 default: 399 pr_warn("Received unexpected message type %d with dir %d from session %s\n", 400 type, dir, srv_sess->sessname); 401 return -EINVAL; 402 } 403 404 /* 405 * Since ret is passed to rtrs to handle the failure case, we 406 * just return 0 at the end otherwise callers in rtrs would call 407 * send_io_resp_imm again to print redundant err message. 408 */ 409 rtrs_srv_resp_rdma(id, ret); 410 return 0; 411 } 412 413 static struct rnbd_srv_sess_dev 414 *rnbd_sess_dev_alloc(struct rnbd_srv_session *srv_sess) 415 { 416 struct rnbd_srv_sess_dev *sess_dev; 417 int error; 418 419 sess_dev = kzalloc(sizeof(*sess_dev), GFP_KERNEL); 420 if (!sess_dev) 421 return ERR_PTR(-ENOMEM); 422 423 error = xa_alloc(&srv_sess->index_idr, &sess_dev->device_id, sess_dev, 424 xa_limit_32b, GFP_NOWAIT); 425 if (error < 0) { 426 pr_warn("Allocating idr failed, err: %d\n", error); 427 kfree(sess_dev); 428 return ERR_PTR(error); 429 } 430 431 return sess_dev; 432 } 433 434 static struct rnbd_srv_dev *rnbd_srv_init_srv_dev(struct block_device *bdev) 435 { 436 struct rnbd_srv_dev *dev; 437 438 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 439 if (!dev) 440 return ERR_PTR(-ENOMEM); 441 442 snprintf(dev->id, sizeof(dev->id), "%pg", bdev); 443 kref_init(&dev->kref); 444 INIT_LIST_HEAD(&dev->sess_dev_list); 445 mutex_init(&dev->lock); 446 447 return dev; 448 } 449 450 static struct rnbd_srv_dev * 451 rnbd_srv_find_or_add_srv_dev(struct rnbd_srv_dev *new_dev) 452 { 453 struct rnbd_srv_dev *dev; 454 455 spin_lock(&dev_lock); 456 list_for_each_entry(dev, &dev_list, list) { 457 if (!strncmp(dev->id, new_dev->id, sizeof(dev->id))) { 458 if (!kref_get_unless_zero(&dev->kref)) 459 /* 460 * We lost the race, device is almost dead. 461 * Continue traversing to find a valid one. 462 */ 463 continue; 464 spin_unlock(&dev_lock); 465 return dev; 466 } 467 } 468 list_add(&new_dev->list, &dev_list); 469 spin_unlock(&dev_lock); 470 471 return new_dev; 472 } 473 474 static int rnbd_srv_check_update_open_perm(struct rnbd_srv_dev *srv_dev, 475 struct rnbd_srv_session *srv_sess, 476 enum rnbd_access_mode access_mode) 477 { 478 int ret = -EPERM; 479 480 mutex_lock(&srv_dev->lock); 481 482 switch (access_mode) { 483 case RNBD_ACCESS_RO: 484 ret = 0; 485 break; 486 case RNBD_ACCESS_RW: 487 if (srv_dev->open_write_cnt == 0) { 488 srv_dev->open_write_cnt++; 489 ret = 0; 490 } else { 491 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", 492 srv_dev->id, srv_sess->sessname, 493 srv_dev->open_write_cnt, 494 rnbd_access_mode_str(access_mode)); 495 } 496 break; 497 case RNBD_ACCESS_MIGRATION: 498 if (srv_dev->open_write_cnt < 2) { 499 srv_dev->open_write_cnt++; 500 ret = 0; 501 } else { 502 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", 503 srv_dev->id, srv_sess->sessname, 504 srv_dev->open_write_cnt, 505 rnbd_access_mode_str(access_mode)); 506 } 507 break; 508 default: 509 pr_err("Received mapping request for device '%s' on session %s with invalid access mode: %d\n", 510 srv_dev->id, srv_sess->sessname, access_mode); 511 ret = -EINVAL; 512 } 513 514 mutex_unlock(&srv_dev->lock); 515 516 return ret; 517 } 518 519 static struct rnbd_srv_dev * 520 rnbd_srv_get_or_create_srv_dev(struct rnbd_dev *rnbd_dev, 521 struct rnbd_srv_session *srv_sess, 522 enum rnbd_access_mode access_mode) 523 { 524 int ret; 525 struct rnbd_srv_dev *new_dev, *dev; 526 527 new_dev = rnbd_srv_init_srv_dev(rnbd_dev->bdev); 528 if (IS_ERR(new_dev)) 529 return new_dev; 530 531 dev = rnbd_srv_find_or_add_srv_dev(new_dev); 532 if (dev != new_dev) 533 kfree(new_dev); 534 535 ret = rnbd_srv_check_update_open_perm(dev, srv_sess, access_mode); 536 if (ret) { 537 rnbd_put_srv_dev(dev); 538 return ERR_PTR(ret); 539 } 540 541 return dev; 542 } 543 544 static void rnbd_srv_fill_msg_open_rsp(struct rnbd_msg_open_rsp *rsp, 545 struct rnbd_srv_sess_dev *sess_dev) 546 { 547 struct rnbd_dev *rnbd_dev = sess_dev->rnbd_dev; 548 549 rsp->hdr.type = cpu_to_le16(RNBD_MSG_OPEN_RSP); 550 rsp->device_id = 551 cpu_to_le32(sess_dev->device_id); 552 rsp->nsectors = 553 cpu_to_le64(get_capacity(rnbd_dev->bdev->bd_disk)); 554 rsp->logical_block_size = 555 cpu_to_le16(bdev_logical_block_size(rnbd_dev->bdev)); 556 rsp->physical_block_size = 557 cpu_to_le16(bdev_physical_block_size(rnbd_dev->bdev)); 558 rsp->max_segments = 559 cpu_to_le16(rnbd_dev_get_max_segs(rnbd_dev)); 560 rsp->max_hw_sectors = 561 cpu_to_le32(rnbd_dev_get_max_hw_sects(rnbd_dev)); 562 rsp->max_write_same_sectors = 0; 563 rsp->max_discard_sectors = 564 cpu_to_le32(rnbd_dev_get_max_discard_sects(rnbd_dev)); 565 rsp->discard_granularity = 566 cpu_to_le32(rnbd_dev_get_discard_granularity(rnbd_dev)); 567 rsp->discard_alignment = 568 cpu_to_le32(rnbd_dev_get_discard_alignment(rnbd_dev)); 569 rsp->secure_discard = 570 cpu_to_le16(rnbd_dev_get_secure_discard(rnbd_dev)); 571 rsp->cache_policy = 0; 572 if (bdev_write_cache(rnbd_dev->bdev)) 573 rsp->cache_policy |= RNBD_WRITEBACK; 574 if (bdev_fua(rnbd_dev->bdev)) 575 rsp->cache_policy |= RNBD_FUA; 576 } 577 578 static struct rnbd_srv_sess_dev * 579 rnbd_srv_create_set_sess_dev(struct rnbd_srv_session *srv_sess, 580 const struct rnbd_msg_open *open_msg, 581 struct rnbd_dev *rnbd_dev, fmode_t open_flags, 582 struct rnbd_srv_dev *srv_dev) 583 { 584 struct rnbd_srv_sess_dev *sdev = rnbd_sess_dev_alloc(srv_sess); 585 586 if (IS_ERR(sdev)) 587 return sdev; 588 589 kref_init(&sdev->kref); 590 591 strscpy(sdev->pathname, open_msg->dev_name, sizeof(sdev->pathname)); 592 593 sdev->rnbd_dev = rnbd_dev; 594 sdev->sess = srv_sess; 595 sdev->dev = srv_dev; 596 sdev->open_flags = open_flags; 597 sdev->access_mode = open_msg->access_mode; 598 599 return sdev; 600 } 601 602 static char *rnbd_srv_get_full_path(struct rnbd_srv_session *srv_sess, 603 const char *dev_name) 604 { 605 char *full_path; 606 char *a, *b; 607 608 full_path = kmalloc(PATH_MAX, GFP_KERNEL); 609 if (!full_path) 610 return ERR_PTR(-ENOMEM); 611 612 /* 613 * Replace %SESSNAME% with a real session name in order to 614 * create device namespace. 615 */ 616 a = strnstr(dev_search_path, "%SESSNAME%", sizeof(dev_search_path)); 617 if (a) { 618 int len = a - dev_search_path; 619 620 len = snprintf(full_path, PATH_MAX, "%.*s/%s/%s", len, 621 dev_search_path, srv_sess->sessname, dev_name); 622 if (len >= PATH_MAX) { 623 pr_err("Too long path: %s, %s, %s\n", 624 dev_search_path, srv_sess->sessname, dev_name); 625 kfree(full_path); 626 return ERR_PTR(-EINVAL); 627 } 628 } else { 629 snprintf(full_path, PATH_MAX, "%s/%s", 630 dev_search_path, dev_name); 631 } 632 633 /* eliminitate duplicated slashes */ 634 a = strchr(full_path, '/'); 635 b = a; 636 while (*b != '\0') { 637 if (*b == '/' && *a == '/') { 638 b++; 639 } else { 640 a++; 641 *a = *b; 642 b++; 643 } 644 } 645 a++; 646 *a = '\0'; 647 648 return full_path; 649 } 650 651 static int process_msg_sess_info(struct rnbd_srv_session *srv_sess, 652 const void *msg, size_t len, 653 void *data, size_t datalen) 654 { 655 const struct rnbd_msg_sess_info *sess_info_msg = msg; 656 struct rnbd_msg_sess_info_rsp *rsp = data; 657 658 srv_sess->ver = min_t(u8, sess_info_msg->ver, RNBD_PROTO_VER_MAJOR); 659 660 trace_process_msg_sess_info(srv_sess, sess_info_msg); 661 662 rsp->hdr.type = cpu_to_le16(RNBD_MSG_SESS_INFO_RSP); 663 rsp->ver = srv_sess->ver; 664 665 return 0; 666 } 667 668 /** 669 * find_srv_sess_dev() - a dev is already opened by this name 670 * @srv_sess: the session to search. 671 * @dev_name: string containing the name of the device. 672 * 673 * Return struct rnbd_srv_sess_dev if srv_sess already opened the dev_name 674 * NULL if the session didn't open the device yet. 675 */ 676 static struct rnbd_srv_sess_dev * 677 find_srv_sess_dev(struct rnbd_srv_session *srv_sess, const char *dev_name) 678 { 679 struct rnbd_srv_sess_dev *sess_dev; 680 unsigned long index; 681 682 if (xa_empty(&srv_sess->index_idr)) 683 return NULL; 684 685 xa_for_each(&srv_sess->index_idr, index, sess_dev) 686 if (!strcmp(sess_dev->pathname, dev_name)) 687 return sess_dev; 688 689 return NULL; 690 } 691 692 static int process_msg_open(struct rnbd_srv_session *srv_sess, 693 const void *msg, size_t len, 694 void *data, size_t datalen) 695 { 696 int ret; 697 struct rnbd_srv_dev *srv_dev; 698 struct rnbd_srv_sess_dev *srv_sess_dev; 699 const struct rnbd_msg_open *open_msg = msg; 700 fmode_t open_flags; 701 char *full_path; 702 struct rnbd_dev *rnbd_dev; 703 struct rnbd_msg_open_rsp *rsp = data; 704 705 trace_process_msg_open(srv_sess, open_msg); 706 707 open_flags = FMODE_READ; 708 if (open_msg->access_mode != RNBD_ACCESS_RO) 709 open_flags |= FMODE_WRITE; 710 711 mutex_lock(&srv_sess->lock); 712 713 srv_sess_dev = find_srv_sess_dev(srv_sess, open_msg->dev_name); 714 if (srv_sess_dev) 715 goto fill_response; 716 717 if ((strlen(dev_search_path) + strlen(open_msg->dev_name)) 718 >= PATH_MAX) { 719 pr_err("Opening device for session %s failed, device path too long. '%s/%s' is longer than PATH_MAX (%d)\n", 720 srv_sess->sessname, dev_search_path, open_msg->dev_name, 721 PATH_MAX); 722 ret = -EINVAL; 723 goto reject; 724 } 725 if (strstr(open_msg->dev_name, "..")) { 726 pr_err("Opening device for session %s failed, device path %s contains relative path ..\n", 727 srv_sess->sessname, open_msg->dev_name); 728 ret = -EINVAL; 729 goto reject; 730 } 731 full_path = rnbd_srv_get_full_path(srv_sess, open_msg->dev_name); 732 if (IS_ERR(full_path)) { 733 ret = PTR_ERR(full_path); 734 pr_err("Opening device '%s' for client %s failed, failed to get device full path, err: %d\n", 735 open_msg->dev_name, srv_sess->sessname, ret); 736 goto reject; 737 } 738 739 rnbd_dev = rnbd_dev_open(full_path, open_flags); 740 if (IS_ERR(rnbd_dev)) { 741 pr_err("Opening device '%s' on session %s failed, failed to open the block device, err: %ld\n", 742 full_path, srv_sess->sessname, PTR_ERR(rnbd_dev)); 743 ret = PTR_ERR(rnbd_dev); 744 goto free_path; 745 } 746 747 srv_dev = rnbd_srv_get_or_create_srv_dev(rnbd_dev, srv_sess, 748 open_msg->access_mode); 749 if (IS_ERR(srv_dev)) { 750 pr_err("Opening device '%s' on session %s failed, creating srv_dev failed, err: %ld\n", 751 full_path, srv_sess->sessname, PTR_ERR(srv_dev)); 752 ret = PTR_ERR(srv_dev); 753 goto rnbd_dev_close; 754 } 755 756 srv_sess_dev = rnbd_srv_create_set_sess_dev(srv_sess, open_msg, 757 rnbd_dev, open_flags, 758 srv_dev); 759 if (IS_ERR(srv_sess_dev)) { 760 pr_err("Opening device '%s' on session %s failed, creating sess_dev failed, err: %ld\n", 761 full_path, srv_sess->sessname, PTR_ERR(srv_sess_dev)); 762 ret = PTR_ERR(srv_sess_dev); 763 goto srv_dev_put; 764 } 765 766 /* Create the srv_dev sysfs files if they haven't been created yet. The 767 * reason to delay the creation is not to create the sysfs files before 768 * we are sure the device can be opened. 769 */ 770 mutex_lock(&srv_dev->lock); 771 if (!srv_dev->dev_kobj.state_in_sysfs) { 772 ret = rnbd_srv_create_dev_sysfs(srv_dev, rnbd_dev->bdev); 773 if (ret) { 774 mutex_unlock(&srv_dev->lock); 775 rnbd_srv_err(srv_sess_dev, 776 "Opening device failed, failed to create device sysfs files, err: %d\n", 777 ret); 778 goto free_srv_sess_dev; 779 } 780 } 781 782 ret = rnbd_srv_create_dev_session_sysfs(srv_sess_dev); 783 if (ret) { 784 mutex_unlock(&srv_dev->lock); 785 rnbd_srv_err(srv_sess_dev, 786 "Opening device failed, failed to create dev client sysfs files, err: %d\n", 787 ret); 788 goto free_srv_sess_dev; 789 } 790 791 list_add(&srv_sess_dev->dev_list, &srv_dev->sess_dev_list); 792 mutex_unlock(&srv_dev->lock); 793 794 rnbd_srv_info(srv_sess_dev, "Opened device '%s'\n", srv_dev->id); 795 796 kfree(full_path); 797 798 fill_response: 799 rnbd_srv_fill_msg_open_rsp(rsp, srv_sess_dev); 800 mutex_unlock(&srv_sess->lock); 801 return 0; 802 803 free_srv_sess_dev: 804 xa_erase(&srv_sess->index_idr, srv_sess_dev->device_id); 805 synchronize_rcu(); 806 kfree(srv_sess_dev); 807 srv_dev_put: 808 if (open_msg->access_mode != RNBD_ACCESS_RO) { 809 mutex_lock(&srv_dev->lock); 810 srv_dev->open_write_cnt--; 811 mutex_unlock(&srv_dev->lock); 812 } 813 rnbd_put_srv_dev(srv_dev); 814 rnbd_dev_close: 815 rnbd_dev_close(rnbd_dev); 816 free_path: 817 kfree(full_path); 818 reject: 819 mutex_unlock(&srv_sess->lock); 820 return ret; 821 } 822 823 static struct rtrs_srv_ctx *rtrs_ctx; 824 825 static struct rtrs_srv_ops rtrs_ops; 826 static int __init rnbd_srv_init_module(void) 827 { 828 int err; 829 830 BUILD_BUG_ON(sizeof(struct rnbd_msg_hdr) != 4); 831 BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info) != 36); 832 BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info_rsp) != 36); 833 BUILD_BUG_ON(sizeof(struct rnbd_msg_open) != 264); 834 BUILD_BUG_ON(sizeof(struct rnbd_msg_close) != 8); 835 BUILD_BUG_ON(sizeof(struct rnbd_msg_open_rsp) != 56); 836 rtrs_ops = (struct rtrs_srv_ops) { 837 .rdma_ev = rnbd_srv_rdma_ev, 838 .link_ev = rnbd_srv_link_ev, 839 }; 840 rtrs_ctx = rtrs_srv_open(&rtrs_ops, port_nr); 841 if (IS_ERR(rtrs_ctx)) { 842 err = PTR_ERR(rtrs_ctx); 843 pr_err("rtrs_srv_open(), err: %d\n", err); 844 return err; 845 } 846 847 err = rnbd_srv_create_sysfs_files(); 848 if (err) { 849 pr_err("rnbd_srv_create_sysfs_files(), err: %d\n", err); 850 rtrs_srv_close(rtrs_ctx); 851 return err; 852 } 853 854 return 0; 855 } 856 857 static void __exit rnbd_srv_cleanup_module(void) 858 { 859 rtrs_srv_close(rtrs_ctx); 860 WARN_ON(!list_empty(&sess_list)); 861 rnbd_srv_destroy_sysfs_files(); 862 } 863 864 module_init(rnbd_srv_init_module); 865 module_exit(rnbd_srv_cleanup_module); 866