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 static struct rnbd_srv_sess_dev * 89 rnbd_get_sess_dev(int dev_id, struct rnbd_srv_session *srv_sess) 90 { 91 struct rnbd_srv_sess_dev *sess_dev; 92 int ret = 0; 93 94 rcu_read_lock(); 95 sess_dev = xa_load(&srv_sess->index_idr, dev_id); 96 if (sess_dev) 97 ret = kref_get_unless_zero(&sess_dev->kref); 98 rcu_read_unlock(); 99 100 if (!sess_dev || !ret) 101 return ERR_PTR(-ENXIO); 102 103 return sess_dev; 104 } 105 106 static void rnbd_dev_bi_end_io(struct bio *bio) 107 { 108 struct rnbd_io_private *rnbd_priv = bio->bi_private; 109 struct rnbd_srv_sess_dev *sess_dev = rnbd_priv->sess_dev; 110 111 rnbd_put_sess_dev(sess_dev); 112 rtrs_srv_resp_rdma(rnbd_priv->id, blk_status_to_errno(bio->bi_status)); 113 114 kfree(rnbd_priv); 115 bio_put(bio); 116 } 117 118 static int process_rdma(struct rnbd_srv_session *srv_sess, 119 struct rtrs_srv_op *id, void *data, u32 datalen, 120 const void *usr, size_t usrlen) 121 { 122 const struct rnbd_msg_io *msg = usr; 123 struct rnbd_io_private *priv; 124 struct rnbd_srv_sess_dev *sess_dev; 125 u32 dev_id; 126 int err; 127 struct bio *bio; 128 short prio; 129 130 trace_process_rdma(srv_sess, msg, id, datalen, usrlen); 131 132 priv = kmalloc(sizeof(*priv), GFP_KERNEL); 133 if (!priv) 134 return -ENOMEM; 135 136 dev_id = le32_to_cpu(msg->device_id); 137 138 sess_dev = rnbd_get_sess_dev(dev_id, srv_sess); 139 if (IS_ERR(sess_dev)) { 140 pr_err_ratelimited("Got I/O request on session %s for unknown device id %d\n", 141 srv_sess->sessname, dev_id); 142 err = -ENOTCONN; 143 goto err; 144 } 145 146 priv->sess_dev = sess_dev; 147 priv->id = id; 148 149 bio = bio_alloc(sess_dev->rnbd_dev->bdev, 1, 150 rnbd_to_bio_flags(le32_to_cpu(msg->rw)), GFP_KERNEL); 151 if (bio_add_page(bio, virt_to_page(data), datalen, 152 offset_in_page(data)) != datalen) { 153 rnbd_srv_err(sess_dev, "Failed to map data to bio\n"); 154 err = -EINVAL; 155 goto bio_put; 156 } 157 158 bio->bi_end_io = rnbd_dev_bi_end_io; 159 bio->bi_private = priv; 160 bio->bi_iter.bi_sector = le64_to_cpu(msg->sector); 161 bio->bi_iter.bi_size = le32_to_cpu(msg->bi_size); 162 prio = srv_sess->ver < RNBD_PROTO_VER_MAJOR || 163 usrlen < sizeof(*msg) ? 0 : le16_to_cpu(msg->prio); 164 bio_set_prio(bio, prio); 165 166 submit_bio(bio); 167 168 return 0; 169 170 bio_put: 171 bio_put(bio); 172 rnbd_put_sess_dev(sess_dev); 173 err: 174 kfree(priv); 175 return err; 176 } 177 178 static void destroy_device(struct kref *kref) 179 { 180 struct rnbd_srv_dev *dev = container_of(kref, struct rnbd_srv_dev, kref); 181 182 WARN_ONCE(!list_empty(&dev->sess_dev_list), 183 "Device %s is being destroyed but still in use!\n", 184 dev->id); 185 186 spin_lock(&dev_lock); 187 list_del(&dev->list); 188 spin_unlock(&dev_lock); 189 190 mutex_destroy(&dev->lock); 191 if (dev->dev_kobj.state_in_sysfs) 192 /* 193 * Destroy kobj only if it was really created. 194 */ 195 rnbd_srv_destroy_dev_sysfs(dev); 196 else 197 kfree(dev); 198 } 199 200 static void rnbd_put_srv_dev(struct rnbd_srv_dev *dev) 201 { 202 kref_put(&dev->kref, destroy_device); 203 } 204 205 void rnbd_destroy_sess_dev(struct rnbd_srv_sess_dev *sess_dev, bool keep_id) 206 { 207 DECLARE_COMPLETION_ONSTACK(dc); 208 209 if (keep_id) 210 /* free the resources for the id but don't */ 211 /* allow to re-use the id itself because it */ 212 /* is still used by the client */ 213 xa_cmpxchg(&sess_dev->sess->index_idr, sess_dev->device_id, 214 sess_dev, NULL, 0); 215 else 216 xa_erase(&sess_dev->sess->index_idr, sess_dev->device_id); 217 synchronize_rcu(); 218 219 sess_dev->destroy_comp = &dc; 220 rnbd_put_sess_dev(sess_dev); 221 wait_for_completion(&dc); /* wait for inflights to drop to zero */ 222 223 rnbd_dev_close(sess_dev->rnbd_dev); 224 mutex_lock(&sess_dev->dev->lock); 225 list_del(&sess_dev->dev_list); 226 if (sess_dev->open_flags & FMODE_WRITE) 227 sess_dev->dev->open_write_cnt--; 228 mutex_unlock(&sess_dev->dev->lock); 229 230 rnbd_put_srv_dev(sess_dev->dev); 231 232 rnbd_srv_info(sess_dev, "Device closed\n"); 233 kfree(sess_dev); 234 } 235 236 static void destroy_sess(struct rnbd_srv_session *srv_sess) 237 { 238 struct rnbd_srv_sess_dev *sess_dev; 239 unsigned long index; 240 241 if (xa_empty(&srv_sess->index_idr)) 242 goto out; 243 244 trace_destroy_sess(srv_sess); 245 246 mutex_lock(&srv_sess->lock); 247 xa_for_each(&srv_sess->index_idr, index, sess_dev) 248 rnbd_srv_destroy_dev_session_sysfs(sess_dev); 249 mutex_unlock(&srv_sess->lock); 250 251 out: 252 xa_destroy(&srv_sess->index_idr); 253 254 pr_info("RTRS Session %s disconnected\n", srv_sess->sessname); 255 256 mutex_lock(&sess_lock); 257 list_del(&srv_sess->list); 258 mutex_unlock(&sess_lock); 259 260 mutex_destroy(&srv_sess->lock); 261 kfree(srv_sess); 262 } 263 264 static int create_sess(struct rtrs_srv_sess *rtrs) 265 { 266 struct rnbd_srv_session *srv_sess; 267 char pathname[NAME_MAX]; 268 int err; 269 270 err = rtrs_srv_get_path_name(rtrs, pathname, sizeof(pathname)); 271 if (err) { 272 pr_err("rtrs_srv_get_path_name(%s): %d\n", pathname, err); 273 274 return err; 275 } 276 srv_sess = kzalloc(sizeof(*srv_sess), GFP_KERNEL); 277 if (!srv_sess) 278 return -ENOMEM; 279 280 srv_sess->queue_depth = rtrs_srv_get_queue_depth(rtrs); 281 xa_init_flags(&srv_sess->index_idr, XA_FLAGS_ALLOC); 282 mutex_init(&srv_sess->lock); 283 mutex_lock(&sess_lock); 284 list_add(&srv_sess->list, &sess_list); 285 mutex_unlock(&sess_lock); 286 287 srv_sess->rtrs = rtrs; 288 strscpy(srv_sess->sessname, pathname, sizeof(srv_sess->sessname)); 289 290 rtrs_srv_set_sess_priv(rtrs, srv_sess); 291 292 trace_create_sess(srv_sess); 293 294 return 0; 295 } 296 297 static int rnbd_srv_link_ev(struct rtrs_srv_sess *rtrs, 298 enum rtrs_srv_link_ev ev, void *priv) 299 { 300 struct rnbd_srv_session *srv_sess = priv; 301 302 switch (ev) { 303 case RTRS_SRV_LINK_EV_CONNECTED: 304 return create_sess(rtrs); 305 306 case RTRS_SRV_LINK_EV_DISCONNECTED: 307 if (WARN_ON_ONCE(!srv_sess)) 308 return -EINVAL; 309 310 destroy_sess(srv_sess); 311 return 0; 312 313 default: 314 pr_warn("Received unknown RTRS session event %d from session %s\n", 315 ev, srv_sess->sessname); 316 return -EINVAL; 317 } 318 } 319 320 void rnbd_srv_sess_dev_force_close(struct rnbd_srv_sess_dev *sess_dev, 321 struct kobj_attribute *attr) 322 { 323 struct rnbd_srv_session *sess = sess_dev->sess; 324 325 /* It is already started to close by client's close message. */ 326 if (!mutex_trylock(&sess->lock)) 327 return; 328 329 sess_dev->keep_id = true; 330 /* first remove sysfs itself to avoid deadlock */ 331 sysfs_remove_file_self(&sess_dev->kobj, &attr->attr); 332 rnbd_srv_destroy_dev_session_sysfs(sess_dev); 333 mutex_unlock(&sess->lock); 334 } 335 336 static void process_msg_close(struct rnbd_srv_session *srv_sess, 337 void *data, size_t datalen, const void *usr, 338 size_t usrlen) 339 { 340 const struct rnbd_msg_close *close_msg = usr; 341 struct rnbd_srv_sess_dev *sess_dev; 342 343 trace_process_msg_close(srv_sess, close_msg); 344 345 sess_dev = rnbd_get_sess_dev(le32_to_cpu(close_msg->device_id), 346 srv_sess); 347 if (IS_ERR(sess_dev)) 348 return; 349 350 rnbd_put_sess_dev(sess_dev); 351 mutex_lock(&srv_sess->lock); 352 rnbd_srv_destroy_dev_session_sysfs(sess_dev); 353 mutex_unlock(&srv_sess->lock); 354 } 355 356 static int process_msg_open(struct rnbd_srv_session *srv_sess, 357 const void *msg, size_t len, 358 void *data, size_t datalen); 359 360 static int process_msg_sess_info(struct rnbd_srv_session *srv_sess, 361 const void *msg, size_t len, 362 void *data, size_t datalen); 363 364 static int rnbd_srv_rdma_ev(void *priv, 365 struct rtrs_srv_op *id, int dir, 366 void *data, size_t datalen, const void *usr, 367 size_t usrlen) 368 { 369 struct rnbd_srv_session *srv_sess = priv; 370 const struct rnbd_msg_hdr *hdr = usr; 371 int ret = 0; 372 u16 type; 373 374 if (WARN_ON_ONCE(!srv_sess)) 375 return -ENODEV; 376 377 type = le16_to_cpu(hdr->type); 378 379 switch (type) { 380 case RNBD_MSG_IO: 381 return process_rdma(srv_sess, id, data, datalen, usr, usrlen); 382 case RNBD_MSG_CLOSE: 383 process_msg_close(srv_sess, data, datalen, usr, usrlen); 384 break; 385 case RNBD_MSG_OPEN: 386 ret = process_msg_open(srv_sess, usr, usrlen, data, datalen); 387 break; 388 case RNBD_MSG_SESS_INFO: 389 ret = process_msg_sess_info(srv_sess, usr, usrlen, data, 390 datalen); 391 break; 392 default: 393 pr_warn("Received unexpected message type %d with dir %d from session %s\n", 394 type, dir, srv_sess->sessname); 395 return -EINVAL; 396 } 397 398 /* 399 * Since ret is passed to rtrs to handle the failure case, we 400 * just return 0 at the end otherwise callers in rtrs would call 401 * send_io_resp_imm again to print redundant err message. 402 */ 403 rtrs_srv_resp_rdma(id, ret); 404 return 0; 405 } 406 407 static struct rnbd_srv_sess_dev 408 *rnbd_sess_dev_alloc(struct rnbd_srv_session *srv_sess) 409 { 410 struct rnbd_srv_sess_dev *sess_dev; 411 int error; 412 413 sess_dev = kzalloc(sizeof(*sess_dev), GFP_KERNEL); 414 if (!sess_dev) 415 return ERR_PTR(-ENOMEM); 416 417 error = xa_alloc(&srv_sess->index_idr, &sess_dev->device_id, sess_dev, 418 xa_limit_32b, GFP_NOWAIT); 419 if (error < 0) { 420 pr_warn("Allocating idr failed, err: %d\n", error); 421 kfree(sess_dev); 422 return ERR_PTR(error); 423 } 424 425 return sess_dev; 426 } 427 428 static struct rnbd_srv_dev *rnbd_srv_init_srv_dev(struct block_device *bdev) 429 { 430 struct rnbd_srv_dev *dev; 431 432 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 433 if (!dev) 434 return ERR_PTR(-ENOMEM); 435 436 snprintf(dev->id, sizeof(dev->id), "%pg", bdev); 437 kref_init(&dev->kref); 438 INIT_LIST_HEAD(&dev->sess_dev_list); 439 mutex_init(&dev->lock); 440 441 return dev; 442 } 443 444 static struct rnbd_srv_dev * 445 rnbd_srv_find_or_add_srv_dev(struct rnbd_srv_dev *new_dev) 446 { 447 struct rnbd_srv_dev *dev; 448 449 spin_lock(&dev_lock); 450 list_for_each_entry(dev, &dev_list, list) { 451 if (!strncmp(dev->id, new_dev->id, sizeof(dev->id))) { 452 if (!kref_get_unless_zero(&dev->kref)) 453 /* 454 * We lost the race, device is almost dead. 455 * Continue traversing to find a valid one. 456 */ 457 continue; 458 spin_unlock(&dev_lock); 459 return dev; 460 } 461 } 462 list_add(&new_dev->list, &dev_list); 463 spin_unlock(&dev_lock); 464 465 return new_dev; 466 } 467 468 static int rnbd_srv_check_update_open_perm(struct rnbd_srv_dev *srv_dev, 469 struct rnbd_srv_session *srv_sess, 470 enum rnbd_access_mode access_mode) 471 { 472 int ret = -EPERM; 473 474 mutex_lock(&srv_dev->lock); 475 476 switch (access_mode) { 477 case RNBD_ACCESS_RO: 478 ret = 0; 479 break; 480 case RNBD_ACCESS_RW: 481 if (srv_dev->open_write_cnt == 0) { 482 srv_dev->open_write_cnt++; 483 ret = 0; 484 } else { 485 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", 486 srv_dev->id, srv_sess->sessname, 487 srv_dev->open_write_cnt, 488 rnbd_access_mode_str(access_mode)); 489 } 490 break; 491 case RNBD_ACCESS_MIGRATION: 492 if (srv_dev->open_write_cnt < 2) { 493 srv_dev->open_write_cnt++; 494 ret = 0; 495 } else { 496 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", 497 srv_dev->id, srv_sess->sessname, 498 srv_dev->open_write_cnt, 499 rnbd_access_mode_str(access_mode)); 500 } 501 break; 502 default: 503 pr_err("Received mapping request for device '%s' on session %s with invalid access mode: %d\n", 504 srv_dev->id, srv_sess->sessname, access_mode); 505 ret = -EINVAL; 506 } 507 508 mutex_unlock(&srv_dev->lock); 509 510 return ret; 511 } 512 513 static struct rnbd_srv_dev * 514 rnbd_srv_get_or_create_srv_dev(struct rnbd_dev *rnbd_dev, 515 struct rnbd_srv_session *srv_sess, 516 enum rnbd_access_mode access_mode) 517 { 518 int ret; 519 struct rnbd_srv_dev *new_dev, *dev; 520 521 new_dev = rnbd_srv_init_srv_dev(rnbd_dev->bdev); 522 if (IS_ERR(new_dev)) 523 return new_dev; 524 525 dev = rnbd_srv_find_or_add_srv_dev(new_dev); 526 if (dev != new_dev) 527 kfree(new_dev); 528 529 ret = rnbd_srv_check_update_open_perm(dev, srv_sess, access_mode); 530 if (ret) { 531 rnbd_put_srv_dev(dev); 532 return ERR_PTR(ret); 533 } 534 535 return dev; 536 } 537 538 static void rnbd_srv_fill_msg_open_rsp(struct rnbd_msg_open_rsp *rsp, 539 struct rnbd_srv_sess_dev *sess_dev) 540 { 541 struct block_device *bdev = sess_dev->rnbd_dev->bdev; 542 543 rsp->hdr.type = cpu_to_le16(RNBD_MSG_OPEN_RSP); 544 rsp->device_id = cpu_to_le32(sess_dev->device_id); 545 rsp->nsectors = cpu_to_le64(bdev_nr_sectors(bdev)); 546 rsp->logical_block_size = cpu_to_le16(bdev_logical_block_size(bdev)); 547 rsp->physical_block_size = cpu_to_le16(bdev_physical_block_size(bdev)); 548 rsp->max_segments = cpu_to_le16(bdev_max_segments(bdev)); 549 rsp->max_hw_sectors = 550 cpu_to_le32(queue_max_hw_sectors(bdev_get_queue(bdev))); 551 rsp->max_write_same_sectors = 0; 552 rsp->max_discard_sectors = cpu_to_le32(bdev_max_discard_sectors(bdev)); 553 rsp->discard_granularity = cpu_to_le32(bdev_discard_granularity(bdev)); 554 rsp->discard_alignment = cpu_to_le32(bdev_discard_alignment(bdev)); 555 rsp->secure_discard = cpu_to_le16(bdev_max_secure_erase_sectors(bdev)); 556 rsp->cache_policy = 0; 557 if (bdev_write_cache(bdev)) 558 rsp->cache_policy |= RNBD_WRITEBACK; 559 if (bdev_fua(bdev)) 560 rsp->cache_policy |= RNBD_FUA; 561 } 562 563 static struct rnbd_srv_sess_dev * 564 rnbd_srv_create_set_sess_dev(struct rnbd_srv_session *srv_sess, 565 const struct rnbd_msg_open *open_msg, 566 struct rnbd_dev *rnbd_dev, fmode_t open_flags, 567 struct rnbd_srv_dev *srv_dev) 568 { 569 struct rnbd_srv_sess_dev *sdev = rnbd_sess_dev_alloc(srv_sess); 570 571 if (IS_ERR(sdev)) 572 return sdev; 573 574 kref_init(&sdev->kref); 575 576 strscpy(sdev->pathname, open_msg->dev_name, sizeof(sdev->pathname)); 577 578 sdev->rnbd_dev = rnbd_dev; 579 sdev->sess = srv_sess; 580 sdev->dev = srv_dev; 581 sdev->open_flags = open_flags; 582 sdev->access_mode = open_msg->access_mode; 583 584 return sdev; 585 } 586 587 static char *rnbd_srv_get_full_path(struct rnbd_srv_session *srv_sess, 588 const char *dev_name) 589 { 590 char *full_path; 591 char *a, *b; 592 593 full_path = kmalloc(PATH_MAX, GFP_KERNEL); 594 if (!full_path) 595 return ERR_PTR(-ENOMEM); 596 597 /* 598 * Replace %SESSNAME% with a real session name in order to 599 * create device namespace. 600 */ 601 a = strnstr(dev_search_path, "%SESSNAME%", sizeof(dev_search_path)); 602 if (a) { 603 int len = a - dev_search_path; 604 605 len = snprintf(full_path, PATH_MAX, "%.*s/%s/%s", len, 606 dev_search_path, srv_sess->sessname, dev_name); 607 if (len >= PATH_MAX) { 608 pr_err("Too long path: %s, %s, %s\n", 609 dev_search_path, srv_sess->sessname, dev_name); 610 kfree(full_path); 611 return ERR_PTR(-EINVAL); 612 } 613 } else { 614 snprintf(full_path, PATH_MAX, "%s/%s", 615 dev_search_path, dev_name); 616 } 617 618 /* eliminitate duplicated slashes */ 619 a = strchr(full_path, '/'); 620 b = a; 621 while (*b != '\0') { 622 if (*b == '/' && *a == '/') { 623 b++; 624 } else { 625 a++; 626 *a = *b; 627 b++; 628 } 629 } 630 a++; 631 *a = '\0'; 632 633 return full_path; 634 } 635 636 static int process_msg_sess_info(struct rnbd_srv_session *srv_sess, 637 const void *msg, size_t len, 638 void *data, size_t datalen) 639 { 640 const struct rnbd_msg_sess_info *sess_info_msg = msg; 641 struct rnbd_msg_sess_info_rsp *rsp = data; 642 643 srv_sess->ver = min_t(u8, sess_info_msg->ver, RNBD_PROTO_VER_MAJOR); 644 645 trace_process_msg_sess_info(srv_sess, sess_info_msg); 646 647 rsp->hdr.type = cpu_to_le16(RNBD_MSG_SESS_INFO_RSP); 648 rsp->ver = srv_sess->ver; 649 650 return 0; 651 } 652 653 /** 654 * find_srv_sess_dev() - a dev is already opened by this name 655 * @srv_sess: the session to search. 656 * @dev_name: string containing the name of the device. 657 * 658 * Return struct rnbd_srv_sess_dev if srv_sess already opened the dev_name 659 * NULL if the session didn't open the device yet. 660 */ 661 static struct rnbd_srv_sess_dev * 662 find_srv_sess_dev(struct rnbd_srv_session *srv_sess, const char *dev_name) 663 { 664 struct rnbd_srv_sess_dev *sess_dev; 665 unsigned long index; 666 667 if (xa_empty(&srv_sess->index_idr)) 668 return NULL; 669 670 xa_for_each(&srv_sess->index_idr, index, sess_dev) 671 if (!strcmp(sess_dev->pathname, dev_name)) 672 return sess_dev; 673 674 return NULL; 675 } 676 677 static int process_msg_open(struct rnbd_srv_session *srv_sess, 678 const void *msg, size_t len, 679 void *data, size_t datalen) 680 { 681 int ret; 682 struct rnbd_srv_dev *srv_dev; 683 struct rnbd_srv_sess_dev *srv_sess_dev; 684 const struct rnbd_msg_open *open_msg = msg; 685 fmode_t open_flags; 686 char *full_path; 687 struct rnbd_dev *rnbd_dev; 688 struct rnbd_msg_open_rsp *rsp = data; 689 690 trace_process_msg_open(srv_sess, open_msg); 691 692 open_flags = FMODE_READ; 693 if (open_msg->access_mode != RNBD_ACCESS_RO) 694 open_flags |= FMODE_WRITE; 695 696 mutex_lock(&srv_sess->lock); 697 698 srv_sess_dev = find_srv_sess_dev(srv_sess, open_msg->dev_name); 699 if (srv_sess_dev) 700 goto fill_response; 701 702 if ((strlen(dev_search_path) + strlen(open_msg->dev_name)) 703 >= PATH_MAX) { 704 pr_err("Opening device for session %s failed, device path too long. '%s/%s' is longer than PATH_MAX (%d)\n", 705 srv_sess->sessname, dev_search_path, open_msg->dev_name, 706 PATH_MAX); 707 ret = -EINVAL; 708 goto reject; 709 } 710 if (strstr(open_msg->dev_name, "..")) { 711 pr_err("Opening device for session %s failed, device path %s contains relative path ..\n", 712 srv_sess->sessname, open_msg->dev_name); 713 ret = -EINVAL; 714 goto reject; 715 } 716 full_path = rnbd_srv_get_full_path(srv_sess, open_msg->dev_name); 717 if (IS_ERR(full_path)) { 718 ret = PTR_ERR(full_path); 719 pr_err("Opening device '%s' for client %s failed, failed to get device full path, err: %d\n", 720 open_msg->dev_name, srv_sess->sessname, ret); 721 goto reject; 722 } 723 724 rnbd_dev = rnbd_dev_open(full_path, open_flags); 725 if (IS_ERR(rnbd_dev)) { 726 pr_err("Opening device '%s' on session %s failed, failed to open the block device, err: %ld\n", 727 full_path, srv_sess->sessname, PTR_ERR(rnbd_dev)); 728 ret = PTR_ERR(rnbd_dev); 729 goto free_path; 730 } 731 732 srv_dev = rnbd_srv_get_or_create_srv_dev(rnbd_dev, srv_sess, 733 open_msg->access_mode); 734 if (IS_ERR(srv_dev)) { 735 pr_err("Opening device '%s' on session %s failed, creating srv_dev failed, err: %ld\n", 736 full_path, srv_sess->sessname, PTR_ERR(srv_dev)); 737 ret = PTR_ERR(srv_dev); 738 goto rnbd_dev_close; 739 } 740 741 srv_sess_dev = rnbd_srv_create_set_sess_dev(srv_sess, open_msg, 742 rnbd_dev, open_flags, 743 srv_dev); 744 if (IS_ERR(srv_sess_dev)) { 745 pr_err("Opening device '%s' on session %s failed, creating sess_dev failed, err: %ld\n", 746 full_path, srv_sess->sessname, PTR_ERR(srv_sess_dev)); 747 ret = PTR_ERR(srv_sess_dev); 748 goto srv_dev_put; 749 } 750 751 /* Create the srv_dev sysfs files if they haven't been created yet. The 752 * reason to delay the creation is not to create the sysfs files before 753 * we are sure the device can be opened. 754 */ 755 mutex_lock(&srv_dev->lock); 756 if (!srv_dev->dev_kobj.state_in_sysfs) { 757 ret = rnbd_srv_create_dev_sysfs(srv_dev, rnbd_dev->bdev); 758 if (ret) { 759 mutex_unlock(&srv_dev->lock); 760 rnbd_srv_err(srv_sess_dev, 761 "Opening device failed, failed to create device sysfs files, err: %d\n", 762 ret); 763 goto free_srv_sess_dev; 764 } 765 } 766 767 ret = rnbd_srv_create_dev_session_sysfs(srv_sess_dev); 768 if (ret) { 769 mutex_unlock(&srv_dev->lock); 770 rnbd_srv_err(srv_sess_dev, 771 "Opening device failed, failed to create dev client sysfs files, err: %d\n", 772 ret); 773 goto free_srv_sess_dev; 774 } 775 776 list_add(&srv_sess_dev->dev_list, &srv_dev->sess_dev_list); 777 mutex_unlock(&srv_dev->lock); 778 779 rnbd_srv_info(srv_sess_dev, "Opened device '%s'\n", srv_dev->id); 780 781 kfree(full_path); 782 783 fill_response: 784 rnbd_srv_fill_msg_open_rsp(rsp, srv_sess_dev); 785 mutex_unlock(&srv_sess->lock); 786 return 0; 787 788 free_srv_sess_dev: 789 xa_erase(&srv_sess->index_idr, srv_sess_dev->device_id); 790 synchronize_rcu(); 791 kfree(srv_sess_dev); 792 srv_dev_put: 793 if (open_msg->access_mode != RNBD_ACCESS_RO) { 794 mutex_lock(&srv_dev->lock); 795 srv_dev->open_write_cnt--; 796 mutex_unlock(&srv_dev->lock); 797 } 798 rnbd_put_srv_dev(srv_dev); 799 rnbd_dev_close: 800 rnbd_dev_close(rnbd_dev); 801 free_path: 802 kfree(full_path); 803 reject: 804 mutex_unlock(&srv_sess->lock); 805 return ret; 806 } 807 808 static struct rtrs_srv_ctx *rtrs_ctx; 809 810 static struct rtrs_srv_ops rtrs_ops; 811 static int __init rnbd_srv_init_module(void) 812 { 813 int err; 814 815 BUILD_BUG_ON(sizeof(struct rnbd_msg_hdr) != 4); 816 BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info) != 36); 817 BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info_rsp) != 36); 818 BUILD_BUG_ON(sizeof(struct rnbd_msg_open) != 264); 819 BUILD_BUG_ON(sizeof(struct rnbd_msg_close) != 8); 820 BUILD_BUG_ON(sizeof(struct rnbd_msg_open_rsp) != 56); 821 rtrs_ops = (struct rtrs_srv_ops) { 822 .rdma_ev = rnbd_srv_rdma_ev, 823 .link_ev = rnbd_srv_link_ev, 824 }; 825 rtrs_ctx = rtrs_srv_open(&rtrs_ops, port_nr); 826 if (IS_ERR(rtrs_ctx)) { 827 err = PTR_ERR(rtrs_ctx); 828 pr_err("rtrs_srv_open(), err: %d\n", err); 829 return err; 830 } 831 832 err = rnbd_srv_create_sysfs_files(); 833 if (err) { 834 pr_err("rnbd_srv_create_sysfs_files(), err: %d\n", err); 835 rtrs_srv_close(rtrs_ctx); 836 return err; 837 } 838 839 return 0; 840 } 841 842 static void __exit rnbd_srv_cleanup_module(void) 843 { 844 rtrs_srv_close(rtrs_ctx); 845 WARN_ON(!list_empty(&sess_list)); 846 rnbd_srv_destroy_sysfs_files(); 847 } 848 849 module_init(rnbd_srv_init_module); 850 module_exit(rnbd_srv_cleanup_module); 851