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 bio_add_virt_nofail(bio, data, datalen); 151 152 bio->bi_opf = rnbd_to_bio_flags(le32_to_cpu(msg->rw)); 153 if (bio_has_data(bio) && 154 bio->bi_iter.bi_size != le32_to_cpu(msg->bi_size)) { 155 rnbd_srv_err_rl(sess_dev, "Datalen mismatch: bio bi_size (%u), bi_size (%u)\n", 156 bio->bi_iter.bi_size, msg->bi_size); 157 err = -EINVAL; 158 goto bio_put; 159 } 160 bio->bi_end_io = rnbd_dev_bi_end_io; 161 bio->bi_private = priv; 162 bio->bi_iter.bi_sector = le64_to_cpu(msg->sector); 163 prio = srv_sess->ver < RNBD_PROTO_VER_MAJOR || 164 usrlen < sizeof(*msg) ? 0 : le16_to_cpu(msg->prio); 165 bio->bi_ioprio = prio; 166 167 submit_bio(bio); 168 169 return 0; 170 171 bio_put: 172 bio_put(bio); 173 rnbd_put_sess_dev(sess_dev); 174 err: 175 kfree(priv); 176 return err; 177 } 178 179 static void destroy_device(struct kref *kref) 180 { 181 struct rnbd_srv_dev *dev = container_of(kref, struct rnbd_srv_dev, kref); 182 183 WARN_ONCE(!list_empty(&dev->sess_dev_list), 184 "Device %s is being destroyed but still in use!\n", 185 dev->name); 186 187 spin_lock(&dev_lock); 188 list_del(&dev->list); 189 spin_unlock(&dev_lock); 190 191 mutex_destroy(&dev->lock); 192 if (dev->dev_kobj.state_in_sysfs) 193 /* 194 * Destroy kobj only if it was really created. 195 */ 196 rnbd_srv_destroy_dev_sysfs(dev); 197 else 198 kfree(dev); 199 } 200 201 static void rnbd_put_srv_dev(struct rnbd_srv_dev *dev) 202 { 203 kref_put(&dev->kref, destroy_device); 204 } 205 206 void rnbd_destroy_sess_dev(struct rnbd_srv_sess_dev *sess_dev, bool keep_id) 207 { 208 DECLARE_COMPLETION_ONSTACK(dc); 209 210 if (keep_id) 211 /* free the resources for the id but don't */ 212 /* allow to re-use the id itself because it */ 213 /* is still used by the client */ 214 xa_cmpxchg(&sess_dev->sess->index_idr, sess_dev->device_id, 215 sess_dev, NULL, 0); 216 else 217 xa_erase(&sess_dev->sess->index_idr, sess_dev->device_id); 218 synchronize_rcu(); 219 220 sess_dev->destroy_comp = &dc; 221 rnbd_put_sess_dev(sess_dev); 222 wait_for_completion(&dc); /* wait for inflights to drop to zero */ 223 224 fput(sess_dev->bdev_file); 225 mutex_lock(&sess_dev->dev->lock); 226 list_del(&sess_dev->dev_list); 227 if (!sess_dev->readonly) 228 sess_dev->dev->open_write_cnt--; 229 mutex_unlock(&sess_dev->dev->lock); 230 231 rnbd_put_srv_dev(sess_dev->dev); 232 233 rnbd_srv_info(sess_dev, "Device closed\n"); 234 kfree(sess_dev); 235 } 236 237 static void destroy_sess(struct rnbd_srv_session *srv_sess) 238 { 239 struct rnbd_srv_sess_dev *sess_dev; 240 unsigned long index; 241 242 if (xa_empty(&srv_sess->index_idr)) 243 goto out; 244 245 trace_destroy_sess(srv_sess); 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 trace_create_sess(srv_sess); 294 295 return 0; 296 } 297 298 static int rnbd_srv_link_ev(struct rtrs_srv_sess *rtrs, 299 enum rtrs_srv_link_ev ev, void *priv) 300 { 301 struct rnbd_srv_session *srv_sess = priv; 302 303 switch (ev) { 304 case RTRS_SRV_LINK_EV_CONNECTED: 305 return create_sess(rtrs); 306 307 case RTRS_SRV_LINK_EV_DISCONNECTED: 308 if (WARN_ON_ONCE(!srv_sess)) 309 return -EINVAL; 310 311 destroy_sess(srv_sess); 312 return 0; 313 314 default: 315 pr_warn("Received unknown RTRS session event %d from session %s\n", 316 ev, srv_sess->sessname); 317 return -EINVAL; 318 } 319 } 320 321 void rnbd_srv_sess_dev_force_close(struct rnbd_srv_sess_dev *sess_dev, 322 struct kobj_attribute *attr) 323 { 324 struct rnbd_srv_session *sess = sess_dev->sess; 325 326 /* It is already started to close by client's close message. */ 327 if (!mutex_trylock(&sess->lock)) 328 return; 329 330 sess_dev->keep_id = true; 331 /* first remove sysfs itself to avoid deadlock */ 332 sysfs_remove_file_self(&sess_dev->kobj, &attr->attr); 333 rnbd_srv_destroy_dev_session_sysfs(sess_dev); 334 mutex_unlock(&sess->lock); 335 } 336 337 static void process_msg_close(struct rnbd_srv_session *srv_sess, 338 void *data, size_t datalen, const void *usr, 339 size_t usrlen) 340 { 341 const struct rnbd_msg_close *close_msg = usr; 342 struct rnbd_srv_sess_dev *sess_dev; 343 344 trace_process_msg_close(srv_sess, close_msg); 345 346 sess_dev = rnbd_get_sess_dev(le32_to_cpu(close_msg->device_id), 347 srv_sess); 348 if (IS_ERR(sess_dev)) 349 return; 350 351 rnbd_put_sess_dev(sess_dev); 352 mutex_lock(&srv_sess->lock); 353 rnbd_srv_destroy_dev_session_sysfs(sess_dev); 354 mutex_unlock(&srv_sess->lock); 355 } 356 357 static int process_msg_open(struct rnbd_srv_session *srv_sess, 358 const void *msg, size_t len, 359 void *data, size_t datalen); 360 361 static void process_msg_sess_info(struct rnbd_srv_session *srv_sess, 362 const void *msg, size_t len, 363 void *data, size_t datalen); 364 365 static int rnbd_srv_rdma_ev(void *priv, struct rtrs_srv_op *id, 366 void *data, size_t datalen, 367 const void *usr, 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 process_msg_sess_info(srv_sess, usr, usrlen, data, datalen); 390 break; 391 default: 392 pr_warn("Received unexpected message type %d from session %s\n", 393 type, srv_sess->sessname); 394 return -EINVAL; 395 } 396 397 /* 398 * Since ret is passed to rtrs to handle the failure case, we 399 * just return 0 at the end otherwise callers in rtrs would call 400 * send_io_resp_imm again to print redundant err message. 401 */ 402 rtrs_srv_resp_rdma(id, ret); 403 return 0; 404 } 405 406 static struct rnbd_srv_sess_dev 407 *rnbd_sess_dev_alloc(struct rnbd_srv_session *srv_sess) 408 { 409 struct rnbd_srv_sess_dev *sess_dev; 410 int error; 411 412 sess_dev = kzalloc(sizeof(*sess_dev), GFP_KERNEL); 413 if (!sess_dev) 414 return ERR_PTR(-ENOMEM); 415 416 error = xa_alloc(&srv_sess->index_idr, &sess_dev->device_id, sess_dev, 417 xa_limit_32b, GFP_NOWAIT); 418 if (error < 0) { 419 pr_warn("Allocating idr failed, err: %d\n", error); 420 kfree(sess_dev); 421 return ERR_PTR(error); 422 } 423 424 return sess_dev; 425 } 426 427 static struct rnbd_srv_dev *rnbd_srv_init_srv_dev(struct block_device *bdev) 428 { 429 struct rnbd_srv_dev *dev; 430 431 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 432 if (!dev) 433 return ERR_PTR(-ENOMEM); 434 435 snprintf(dev->name, sizeof(dev->name), "%pg", bdev); 436 kref_init(&dev->kref); 437 INIT_LIST_HEAD(&dev->sess_dev_list); 438 mutex_init(&dev->lock); 439 440 return dev; 441 } 442 443 static struct rnbd_srv_dev * 444 rnbd_srv_find_or_add_srv_dev(struct rnbd_srv_dev *new_dev) 445 { 446 struct rnbd_srv_dev *dev; 447 448 spin_lock(&dev_lock); 449 list_for_each_entry(dev, &dev_list, list) { 450 if (!strncmp(dev->name, new_dev->name, sizeof(dev->name))) { 451 if (!kref_get_unless_zero(&dev->kref)) 452 /* 453 * We lost the race, device is almost dead. 454 * Continue traversing to find a valid one. 455 */ 456 continue; 457 spin_unlock(&dev_lock); 458 return dev; 459 } 460 } 461 list_add(&new_dev->list, &dev_list); 462 spin_unlock(&dev_lock); 463 464 return new_dev; 465 } 466 467 static int rnbd_srv_check_update_open_perm(struct rnbd_srv_dev *srv_dev, 468 struct rnbd_srv_session *srv_sess, 469 enum rnbd_access_mode access_mode) 470 { 471 int ret = 0; 472 473 mutex_lock(&srv_dev->lock); 474 475 switch (access_mode) { 476 case RNBD_ACCESS_RO: 477 break; 478 case RNBD_ACCESS_RW: 479 if (srv_dev->open_write_cnt == 0) { 480 srv_dev->open_write_cnt++; 481 } else { 482 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", 483 srv_dev->name, srv_sess->sessname, 484 srv_dev->open_write_cnt, 485 rnbd_access_modes[access_mode].str); 486 ret = -EPERM; 487 } 488 break; 489 case RNBD_ACCESS_MIGRATION: 490 if (srv_dev->open_write_cnt < 2) { 491 srv_dev->open_write_cnt++; 492 } else { 493 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", 494 srv_dev->name, srv_sess->sessname, 495 srv_dev->open_write_cnt, 496 rnbd_access_modes[access_mode].str); 497 ret = -EPERM; 498 } 499 break; 500 default: 501 pr_err("Received mapping request for device '%s' on session %s with invalid access mode: %d\n", 502 srv_dev->name, srv_sess->sessname, access_mode); 503 ret = -EINVAL; 504 } 505 506 mutex_unlock(&srv_dev->lock); 507 508 return ret; 509 } 510 511 static struct rnbd_srv_dev * 512 rnbd_srv_get_or_create_srv_dev(struct block_device *bdev, 513 struct rnbd_srv_session *srv_sess, 514 enum rnbd_access_mode access_mode) 515 { 516 int ret; 517 struct rnbd_srv_dev *new_dev, *dev; 518 519 new_dev = rnbd_srv_init_srv_dev(bdev); 520 if (IS_ERR(new_dev)) 521 return new_dev; 522 523 dev = rnbd_srv_find_or_add_srv_dev(new_dev); 524 if (dev != new_dev) 525 kfree(new_dev); 526 527 ret = rnbd_srv_check_update_open_perm(dev, srv_sess, access_mode); 528 if (ret) { 529 rnbd_put_srv_dev(dev); 530 return ERR_PTR(ret); 531 } 532 533 return dev; 534 } 535 536 static void rnbd_srv_fill_msg_open_rsp(struct rnbd_msg_open_rsp *rsp, 537 struct rnbd_srv_sess_dev *sess_dev) 538 { 539 struct block_device *bdev = file_bdev(sess_dev->bdev_file); 540 541 rsp->hdr.type = cpu_to_le16(RNBD_MSG_OPEN_RSP); 542 rsp->device_id = cpu_to_le32(sess_dev->device_id); 543 rsp->nsectors = cpu_to_le64(bdev_nr_sectors(bdev)); 544 rsp->logical_block_size = cpu_to_le16(bdev_logical_block_size(bdev)); 545 rsp->physical_block_size = cpu_to_le16(bdev_physical_block_size(bdev)); 546 rsp->max_segments = cpu_to_le16(bdev_max_segments(bdev)); 547 rsp->max_hw_sectors = 548 cpu_to_le32(queue_max_hw_sectors(bdev_get_queue(bdev))); 549 rsp->max_write_zeroes_sectors = 550 cpu_to_le32(bdev_write_zeroes_sectors(bdev)); 551 rsp->max_discard_sectors = cpu_to_le32(bdev_max_discard_sectors(bdev)); 552 rsp->discard_granularity = cpu_to_le32(bdev_discard_granularity(bdev)); 553 rsp->discard_alignment = cpu_to_le32(bdev_discard_alignment(bdev)); 554 rsp->secure_discard = cpu_to_le16(bdev_max_secure_erase_sectors(bdev)); 555 rsp->cache_policy = 0; 556 if (bdev_write_cache(bdev)) 557 rsp->cache_policy |= RNBD_WRITEBACK; 558 if (bdev_fua(bdev)) 559 rsp->cache_policy |= RNBD_FUA; 560 } 561 562 static struct rnbd_srv_sess_dev * 563 rnbd_srv_create_set_sess_dev(struct rnbd_srv_session *srv_sess, 564 const struct rnbd_msg_open *open_msg, 565 struct file *bdev_file, bool readonly, 566 struct rnbd_srv_dev *srv_dev) 567 { 568 struct rnbd_srv_sess_dev *sdev = rnbd_sess_dev_alloc(srv_sess); 569 570 if (IS_ERR(sdev)) 571 return sdev; 572 573 kref_init(&sdev->kref); 574 575 strscpy(sdev->pathname, open_msg->dev_name, sizeof(sdev->pathname)); 576 577 sdev->bdev_file = bdev_file; 578 sdev->sess = srv_sess; 579 sdev->dev = srv_dev; 580 sdev->readonly = readonly; 581 sdev->access_mode = open_msg->access_mode; 582 583 return sdev; 584 } 585 586 static char *rnbd_srv_get_full_path(struct rnbd_srv_session *srv_sess, 587 const char *dev_name) 588 { 589 char *full_path; 590 char *a, *b; 591 int len; 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 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 } else { 608 len = snprintf(full_path, PATH_MAX, "%s/%s", 609 dev_search_path, dev_name); 610 } 611 if (len >= PATH_MAX) { 612 pr_err("Too long path: %s, %s, %s\n", 613 dev_search_path, srv_sess->sessname, dev_name); 614 kfree(full_path); 615 return ERR_PTR(-EINVAL); 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 void 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 } 650 651 /** 652 * find_srv_sess_dev() - a dev is already opened by this name 653 * @srv_sess: the session to search. 654 * @dev_name: string containing the name of the device. 655 * 656 * Return struct rnbd_srv_sess_dev if srv_sess already opened the dev_name 657 * NULL if the session didn't open the device yet. 658 */ 659 static struct rnbd_srv_sess_dev * 660 find_srv_sess_dev(struct rnbd_srv_session *srv_sess, const char *dev_name) 661 { 662 struct rnbd_srv_sess_dev *sess_dev; 663 unsigned long index; 664 665 if (xa_empty(&srv_sess->index_idr)) 666 return NULL; 667 668 xa_for_each(&srv_sess->index_idr, index, sess_dev) 669 if (!strcmp(sess_dev->pathname, dev_name)) 670 return sess_dev; 671 672 return NULL; 673 } 674 675 static int process_msg_open(struct rnbd_srv_session *srv_sess, 676 const void *msg, size_t len, 677 void *data, size_t datalen) 678 { 679 int ret; 680 struct rnbd_srv_dev *srv_dev; 681 struct rnbd_srv_sess_dev *srv_sess_dev; 682 const struct rnbd_msg_open *open_msg = msg; 683 struct file *bdev_file; 684 blk_mode_t open_flags = BLK_OPEN_READ; 685 char *full_path; 686 struct rnbd_msg_open_rsp *rsp = data; 687 688 trace_process_msg_open(srv_sess, open_msg); 689 690 if (open_msg->access_mode != RNBD_ACCESS_RO) 691 open_flags |= BLK_OPEN_WRITE; 692 693 mutex_lock(&srv_sess->lock); 694 695 srv_sess_dev = find_srv_sess_dev(srv_sess, open_msg->dev_name); 696 if (srv_sess_dev) 697 goto fill_response; 698 699 if ((strlen(dev_search_path) + strlen(open_msg->dev_name)) 700 >= PATH_MAX) { 701 pr_err("Opening device for session %s failed, device path too long. '%s/%s' is longer than PATH_MAX (%d)\n", 702 srv_sess->sessname, dev_search_path, open_msg->dev_name, 703 PATH_MAX); 704 ret = -EINVAL; 705 goto reject; 706 } 707 if (strstr(open_msg->dev_name, "..")) { 708 pr_err("Opening device for session %s failed, device path %s contains relative path ..\n", 709 srv_sess->sessname, open_msg->dev_name); 710 ret = -EINVAL; 711 goto reject; 712 } 713 full_path = rnbd_srv_get_full_path(srv_sess, open_msg->dev_name); 714 if (IS_ERR(full_path)) { 715 ret = PTR_ERR(full_path); 716 pr_err("Opening device '%s' for client %s failed, failed to get device full path, err: %pe\n", 717 open_msg->dev_name, srv_sess->sessname, full_path); 718 goto reject; 719 } 720 721 bdev_file = bdev_file_open_by_path(full_path, open_flags, NULL, NULL); 722 if (IS_ERR(bdev_file)) { 723 ret = PTR_ERR(bdev_file); 724 pr_err("Opening device '%s' on session %s failed, failed to open the block device, err: %pe\n", 725 full_path, srv_sess->sessname, bdev_file); 726 goto free_path; 727 } 728 729 srv_dev = rnbd_srv_get_or_create_srv_dev(file_bdev(bdev_file), srv_sess, 730 open_msg->access_mode); 731 if (IS_ERR(srv_dev)) { 732 pr_err("Opening device '%s' on session %s failed, creating srv_dev failed, err: %pe\n", 733 full_path, srv_sess->sessname, srv_dev); 734 ret = PTR_ERR(srv_dev); 735 goto blkdev_put; 736 } 737 738 srv_sess_dev = rnbd_srv_create_set_sess_dev(srv_sess, open_msg, 739 bdev_file, 740 open_msg->access_mode == RNBD_ACCESS_RO, 741 srv_dev); 742 if (IS_ERR(srv_sess_dev)) { 743 pr_err("Opening device '%s' on session %s failed, creating sess_dev failed, err: %pe\n", 744 full_path, srv_sess->sessname, srv_sess_dev); 745 ret = PTR_ERR(srv_sess_dev); 746 goto srv_dev_put; 747 } 748 749 /* Create the srv_dev sysfs files if they haven't been created yet. The 750 * reason to delay the creation is not to create the sysfs files before 751 * we are sure the device can be opened. 752 */ 753 mutex_lock(&srv_dev->lock); 754 if (!srv_dev->dev_kobj.state_in_sysfs) { 755 ret = rnbd_srv_create_dev_sysfs(srv_dev, file_bdev(bdev_file)); 756 if (ret) { 757 mutex_unlock(&srv_dev->lock); 758 rnbd_srv_err(srv_sess_dev, 759 "Opening device failed, failed to create device sysfs files, err: %d\n", 760 ret); 761 goto free_srv_sess_dev; 762 } 763 } 764 765 ret = rnbd_srv_create_dev_session_sysfs(srv_sess_dev); 766 if (ret) { 767 mutex_unlock(&srv_dev->lock); 768 rnbd_srv_err(srv_sess_dev, 769 "Opening device failed, failed to create dev client sysfs files, err: %d\n", 770 ret); 771 goto free_srv_sess_dev; 772 } 773 774 list_add(&srv_sess_dev->dev_list, &srv_dev->sess_dev_list); 775 mutex_unlock(&srv_dev->lock); 776 777 rnbd_srv_info(srv_sess_dev, "Opened device '%s'\n", srv_dev->name); 778 779 kfree(full_path); 780 781 fill_response: 782 rnbd_srv_fill_msg_open_rsp(rsp, srv_sess_dev); 783 mutex_unlock(&srv_sess->lock); 784 return 0; 785 786 free_srv_sess_dev: 787 xa_erase(&srv_sess->index_idr, srv_sess_dev->device_id); 788 synchronize_rcu(); 789 kfree(srv_sess_dev); 790 srv_dev_put: 791 if (open_msg->access_mode != RNBD_ACCESS_RO) { 792 mutex_lock(&srv_dev->lock); 793 srv_dev->open_write_cnt--; 794 mutex_unlock(&srv_dev->lock); 795 } 796 rnbd_put_srv_dev(srv_dev); 797 blkdev_put: 798 fput(bdev_file); 799 free_path: 800 kfree(full_path); 801 reject: 802 mutex_unlock(&srv_sess->lock); 803 return ret; 804 } 805 806 static struct rtrs_srv_ctx *rtrs_ctx; 807 808 static struct rtrs_srv_ops rtrs_ops; 809 static int __init rnbd_srv_init_module(void) 810 { 811 int err = 0; 812 813 BUILD_BUG_ON(sizeof(struct rnbd_msg_hdr) != 4); 814 BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info) != 36); 815 BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info_rsp) != 36); 816 BUILD_BUG_ON(sizeof(struct rnbd_msg_open) != 264); 817 BUILD_BUG_ON(sizeof(struct rnbd_msg_close) != 8); 818 BUILD_BUG_ON(sizeof(struct rnbd_msg_open_rsp) != 56); 819 rtrs_ops = (struct rtrs_srv_ops) { 820 .rdma_ev = rnbd_srv_rdma_ev, 821 .link_ev = rnbd_srv_link_ev, 822 }; 823 rtrs_ctx = rtrs_srv_open(&rtrs_ops, port_nr); 824 if (IS_ERR(rtrs_ctx)) { 825 pr_err("rtrs_srv_open(), err: %pe\n", rtrs_ctx); 826 return PTR_ERR(rtrs_ctx); 827 } 828 829 err = rnbd_srv_create_sysfs_files(); 830 if (err) { 831 pr_err("rnbd_srv_create_sysfs_files(), err: %d\n", err); 832 rtrs_srv_close(rtrs_ctx); 833 } 834 835 return err; 836 } 837 838 static void __exit rnbd_srv_cleanup_module(void) 839 { 840 rtrs_srv_close(rtrs_ctx); 841 WARN_ON(!list_empty(&sess_list)); 842 rnbd_srv_destroy_sysfs_files(); 843 } 844 845 module_init(rnbd_srv_init_module); 846 module_exit(rnbd_srv_cleanup_module); 847