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), !!datalen, 149 rnbd_to_bio_flags(le32_to_cpu(msg->rw)), GFP_KERNEL); 150 if (unlikely(!bio)) { 151 err = -ENOMEM; 152 goto put_sess_dev; 153 } 154 155 if (!datalen) { 156 /* 157 * For special requests like DISCARD and WRITE_ZEROES, the datalen is zero. 158 */ 159 bio->bi_iter.bi_size = le32_to_cpu(msg->bi_size); 160 } else { 161 bio_add_virt_nofail(bio, data, datalen); 162 bio->bi_opf = rnbd_to_bio_flags(le32_to_cpu(msg->rw)); 163 if (bio->bi_iter.bi_size != le32_to_cpu(msg->bi_size)) { 164 rnbd_srv_err_rl(sess_dev, 165 "Datalen mismatch: bio bi_size (%u), bi_size (%u)\n", 166 bio->bi_iter.bi_size, msg->bi_size); 167 err = -EINVAL; 168 goto bio_put; 169 } 170 } 171 172 bio->bi_end_io = rnbd_dev_bi_end_io; 173 bio->bi_private = priv; 174 bio->bi_iter.bi_sector = le64_to_cpu(msg->sector); 175 prio = srv_sess->ver < RNBD_PROTO_VER_MAJOR || 176 usrlen < sizeof(*msg) ? 0 : le16_to_cpu(msg->prio); 177 bio->bi_ioprio = prio; 178 179 submit_bio(bio); 180 181 return 0; 182 183 bio_put: 184 bio_put(bio); 185 put_sess_dev: 186 rnbd_put_sess_dev(sess_dev); 187 err: 188 kfree(priv); 189 return err; 190 } 191 192 static void destroy_device(struct kref *kref) 193 { 194 struct rnbd_srv_dev *dev = container_of(kref, struct rnbd_srv_dev, kref); 195 196 WARN_ONCE(!list_empty(&dev->sess_dev_list), 197 "Device %s is being destroyed but still in use!\n", 198 dev->name); 199 200 spin_lock(&dev_lock); 201 list_del(&dev->list); 202 spin_unlock(&dev_lock); 203 204 mutex_destroy(&dev->lock); 205 if (dev->dev_kobj.state_in_sysfs) 206 /* 207 * Destroy kobj only if it was really created. 208 */ 209 rnbd_srv_destroy_dev_sysfs(dev); 210 else 211 kfree(dev); 212 } 213 214 static void rnbd_put_srv_dev(struct rnbd_srv_dev *dev) 215 { 216 kref_put(&dev->kref, destroy_device); 217 } 218 219 void rnbd_destroy_sess_dev(struct rnbd_srv_sess_dev *sess_dev, bool keep_id) 220 { 221 DECLARE_COMPLETION_ONSTACK(dc); 222 223 if (keep_id) 224 /* free the resources for the id but don't */ 225 /* allow to re-use the id itself because it */ 226 /* is still used by the client */ 227 xa_cmpxchg(&sess_dev->sess->index_idr, sess_dev->device_id, 228 sess_dev, NULL, 0); 229 else 230 xa_erase(&sess_dev->sess->index_idr, sess_dev->device_id); 231 synchronize_rcu(); 232 233 sess_dev->destroy_comp = &dc; 234 rnbd_put_sess_dev(sess_dev); 235 wait_for_completion(&dc); /* wait for inflights to drop to zero */ 236 237 fput(sess_dev->bdev_file); 238 mutex_lock(&sess_dev->dev->lock); 239 list_del(&sess_dev->dev_list); 240 if (!sess_dev->readonly) 241 sess_dev->dev->open_write_cnt--; 242 mutex_unlock(&sess_dev->dev->lock); 243 244 rnbd_put_srv_dev(sess_dev->dev); 245 246 rnbd_srv_info(sess_dev, "Device closed\n"); 247 kfree(sess_dev); 248 } 249 250 static void destroy_sess(struct rnbd_srv_session *srv_sess) 251 { 252 struct rnbd_srv_sess_dev *sess_dev; 253 unsigned long index; 254 255 if (xa_empty(&srv_sess->index_idr)) 256 goto out; 257 258 trace_destroy_sess(srv_sess); 259 260 mutex_lock(&srv_sess->lock); 261 xa_for_each(&srv_sess->index_idr, index, sess_dev) 262 rnbd_srv_destroy_dev_session_sysfs(sess_dev); 263 mutex_unlock(&srv_sess->lock); 264 265 out: 266 xa_destroy(&srv_sess->index_idr); 267 268 pr_info("RTRS Session %s disconnected\n", srv_sess->sessname); 269 270 mutex_lock(&sess_lock); 271 list_del(&srv_sess->list); 272 mutex_unlock(&sess_lock); 273 274 mutex_destroy(&srv_sess->lock); 275 kfree(srv_sess); 276 } 277 278 static int create_sess(struct rtrs_srv_sess *rtrs) 279 { 280 struct rnbd_srv_session *srv_sess; 281 char pathname[NAME_MAX]; 282 int err; 283 284 err = rtrs_srv_get_path_name(rtrs, pathname, sizeof(pathname)); 285 if (err) { 286 pr_err("rtrs_srv_get_path_name(%s): %d\n", pathname, err); 287 288 return err; 289 } 290 srv_sess = kzalloc(sizeof(*srv_sess), GFP_KERNEL); 291 if (!srv_sess) 292 return -ENOMEM; 293 294 srv_sess->queue_depth = rtrs_srv_get_queue_depth(rtrs); 295 xa_init_flags(&srv_sess->index_idr, XA_FLAGS_ALLOC); 296 mutex_init(&srv_sess->lock); 297 mutex_lock(&sess_lock); 298 list_add(&srv_sess->list, &sess_list); 299 mutex_unlock(&sess_lock); 300 301 srv_sess->rtrs = rtrs; 302 strscpy(srv_sess->sessname, pathname, sizeof(srv_sess->sessname)); 303 304 rtrs_srv_set_sess_priv(rtrs, srv_sess); 305 306 trace_create_sess(srv_sess); 307 308 return 0; 309 } 310 311 static int rnbd_srv_link_ev(struct rtrs_srv_sess *rtrs, 312 enum rtrs_srv_link_ev ev, void *priv) 313 { 314 struct rnbd_srv_session *srv_sess = priv; 315 316 switch (ev) { 317 case RTRS_SRV_LINK_EV_CONNECTED: 318 return create_sess(rtrs); 319 320 case RTRS_SRV_LINK_EV_DISCONNECTED: 321 if (WARN_ON_ONCE(!srv_sess)) 322 return -EINVAL; 323 324 destroy_sess(srv_sess); 325 return 0; 326 327 default: 328 pr_warn("Received unknown RTRS session event %d from session %s\n", 329 ev, srv_sess->sessname); 330 return -EINVAL; 331 } 332 } 333 334 void rnbd_srv_sess_dev_force_close(struct rnbd_srv_sess_dev *sess_dev, 335 struct kobj_attribute *attr) 336 { 337 struct rnbd_srv_session *sess = sess_dev->sess; 338 339 /* It is already started to close by client's close message. */ 340 if (!mutex_trylock(&sess->lock)) 341 return; 342 343 sess_dev->keep_id = true; 344 /* first remove sysfs itself to avoid deadlock */ 345 sysfs_remove_file_self(&sess_dev->kobj, &attr->attr); 346 rnbd_srv_destroy_dev_session_sysfs(sess_dev); 347 mutex_unlock(&sess->lock); 348 } 349 350 static void process_msg_close(struct rnbd_srv_session *srv_sess, 351 void *data, size_t datalen, const void *usr, 352 size_t usrlen) 353 { 354 const struct rnbd_msg_close *close_msg = usr; 355 struct rnbd_srv_sess_dev *sess_dev; 356 357 trace_process_msg_close(srv_sess, close_msg); 358 359 sess_dev = rnbd_get_sess_dev(le32_to_cpu(close_msg->device_id), 360 srv_sess); 361 if (IS_ERR(sess_dev)) 362 return; 363 364 rnbd_put_sess_dev(sess_dev); 365 mutex_lock(&srv_sess->lock); 366 rnbd_srv_destroy_dev_session_sysfs(sess_dev); 367 mutex_unlock(&srv_sess->lock); 368 } 369 370 static int process_msg_open(struct rnbd_srv_session *srv_sess, 371 const void *msg, size_t len, 372 void *data, size_t datalen); 373 374 static void process_msg_sess_info(struct rnbd_srv_session *srv_sess, 375 const void *msg, size_t len, 376 void *data, size_t datalen); 377 378 static int rnbd_srv_rdma_ev(void *priv, struct rtrs_srv_op *id, 379 void *data, size_t datalen, 380 const void *usr, size_t usrlen) 381 { 382 struct rnbd_srv_session *srv_sess = priv; 383 const struct rnbd_msg_hdr *hdr = usr; 384 int ret = 0; 385 u16 type; 386 387 if (WARN_ON_ONCE(!srv_sess)) 388 return -ENODEV; 389 390 type = le16_to_cpu(hdr->type); 391 392 switch (type) { 393 case RNBD_MSG_IO: 394 return process_rdma(srv_sess, id, data, datalen, usr, usrlen); 395 case RNBD_MSG_CLOSE: 396 process_msg_close(srv_sess, data, datalen, usr, usrlen); 397 break; 398 case RNBD_MSG_OPEN: 399 ret = process_msg_open(srv_sess, usr, usrlen, data, datalen); 400 break; 401 case RNBD_MSG_SESS_INFO: 402 process_msg_sess_info(srv_sess, usr, usrlen, data, datalen); 403 break; 404 default: 405 pr_warn("Received unexpected message type %d from session %s\n", 406 type, srv_sess->sessname); 407 return -EINVAL; 408 } 409 410 /* 411 * Since ret is passed to rtrs to handle the failure case, we 412 * just return 0 at the end otherwise callers in rtrs would call 413 * send_io_resp_imm again to print redundant err message. 414 */ 415 rtrs_srv_resp_rdma(id, ret); 416 return 0; 417 } 418 419 static struct rnbd_srv_sess_dev 420 *rnbd_sess_dev_alloc(struct rnbd_srv_session *srv_sess) 421 { 422 struct rnbd_srv_sess_dev *sess_dev; 423 int error; 424 425 sess_dev = kzalloc(sizeof(*sess_dev), GFP_KERNEL); 426 if (!sess_dev) 427 return ERR_PTR(-ENOMEM); 428 429 error = xa_alloc(&srv_sess->index_idr, &sess_dev->device_id, sess_dev, 430 xa_limit_32b, GFP_NOWAIT); 431 if (error < 0) { 432 pr_warn("Allocating idr failed, err: %d\n", error); 433 kfree(sess_dev); 434 return ERR_PTR(error); 435 } 436 437 return sess_dev; 438 } 439 440 static struct rnbd_srv_dev *rnbd_srv_init_srv_dev(struct block_device *bdev) 441 { 442 struct rnbd_srv_dev *dev; 443 444 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 445 if (!dev) 446 return ERR_PTR(-ENOMEM); 447 448 snprintf(dev->name, sizeof(dev->name), "%pg", bdev); 449 kref_init(&dev->kref); 450 INIT_LIST_HEAD(&dev->sess_dev_list); 451 mutex_init(&dev->lock); 452 453 return dev; 454 } 455 456 static struct rnbd_srv_dev * 457 rnbd_srv_find_or_add_srv_dev(struct rnbd_srv_dev *new_dev) 458 { 459 struct rnbd_srv_dev *dev; 460 461 spin_lock(&dev_lock); 462 list_for_each_entry(dev, &dev_list, list) { 463 if (!strncmp(dev->name, new_dev->name, sizeof(dev->name))) { 464 if (!kref_get_unless_zero(&dev->kref)) 465 /* 466 * We lost the race, device is almost dead. 467 * Continue traversing to find a valid one. 468 */ 469 continue; 470 spin_unlock(&dev_lock); 471 return dev; 472 } 473 } 474 list_add(&new_dev->list, &dev_list); 475 spin_unlock(&dev_lock); 476 477 return new_dev; 478 } 479 480 static int rnbd_srv_check_update_open_perm(struct rnbd_srv_dev *srv_dev, 481 struct rnbd_srv_session *srv_sess, 482 enum rnbd_access_mode access_mode) 483 { 484 int ret = 0; 485 486 mutex_lock(&srv_dev->lock); 487 488 switch (access_mode) { 489 case RNBD_ACCESS_RO: 490 break; 491 case RNBD_ACCESS_RW: 492 if (srv_dev->open_write_cnt == 0) { 493 srv_dev->open_write_cnt++; 494 } else { 495 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", 496 srv_dev->name, srv_sess->sessname, 497 srv_dev->open_write_cnt, 498 rnbd_access_modes[access_mode].str); 499 ret = -EPERM; 500 } 501 break; 502 case RNBD_ACCESS_MIGRATION: 503 if (srv_dev->open_write_cnt < 2) { 504 srv_dev->open_write_cnt++; 505 } else { 506 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", 507 srv_dev->name, srv_sess->sessname, 508 srv_dev->open_write_cnt, 509 rnbd_access_modes[access_mode].str); 510 ret = -EPERM; 511 } 512 break; 513 default: 514 pr_err("Received mapping request for device '%s' on session %s with invalid access mode: %d\n", 515 srv_dev->name, srv_sess->sessname, access_mode); 516 ret = -EINVAL; 517 } 518 519 mutex_unlock(&srv_dev->lock); 520 521 return ret; 522 } 523 524 static struct rnbd_srv_dev * 525 rnbd_srv_get_or_create_srv_dev(struct block_device *bdev, 526 struct rnbd_srv_session *srv_sess, 527 enum rnbd_access_mode access_mode) 528 { 529 int ret; 530 struct rnbd_srv_dev *new_dev, *dev; 531 532 new_dev = rnbd_srv_init_srv_dev(bdev); 533 if (IS_ERR(new_dev)) 534 return new_dev; 535 536 dev = rnbd_srv_find_or_add_srv_dev(new_dev); 537 if (dev != new_dev) 538 kfree(new_dev); 539 540 ret = rnbd_srv_check_update_open_perm(dev, srv_sess, access_mode); 541 if (ret) { 542 rnbd_put_srv_dev(dev); 543 return ERR_PTR(ret); 544 } 545 546 return dev; 547 } 548 549 static void rnbd_srv_fill_msg_open_rsp(struct rnbd_msg_open_rsp *rsp, 550 struct rnbd_srv_sess_dev *sess_dev) 551 { 552 struct block_device *bdev = file_bdev(sess_dev->bdev_file); 553 554 memset(rsp, 0, sizeof(*rsp)); 555 556 rsp->hdr.type = cpu_to_le16(RNBD_MSG_OPEN_RSP); 557 rsp->device_id = cpu_to_le32(sess_dev->device_id); 558 rsp->nsectors = cpu_to_le64(bdev_nr_sectors(bdev)); 559 rsp->logical_block_size = cpu_to_le16(bdev_logical_block_size(bdev)); 560 rsp->physical_block_size = cpu_to_le16(bdev_physical_block_size(bdev)); 561 rsp->max_segments = cpu_to_le16(bdev_max_segments(bdev)); 562 rsp->max_hw_sectors = 563 cpu_to_le32(queue_max_hw_sectors(bdev_get_queue(bdev))); 564 rsp->max_write_zeroes_sectors = 565 cpu_to_le32(bdev_write_zeroes_sectors(bdev)); 566 rsp->max_discard_sectors = cpu_to_le32(bdev_max_discard_sectors(bdev)); 567 rsp->discard_granularity = cpu_to_le32(bdev_discard_granularity(bdev)); 568 rsp->discard_alignment = cpu_to_le32(bdev_discard_alignment(bdev)); 569 rsp->secure_discard = cpu_to_le16(bdev_max_secure_erase_sectors(bdev)); 570 rsp->cache_policy = 0; 571 if (bdev_write_cache(bdev)) 572 rsp->cache_policy |= RNBD_WRITEBACK; 573 if (bdev_fua(bdev)) 574 rsp->cache_policy |= RNBD_FUA; 575 } 576 577 static struct rnbd_srv_sess_dev * 578 rnbd_srv_create_set_sess_dev(struct rnbd_srv_session *srv_sess, 579 const struct rnbd_msg_open *open_msg, 580 struct file *bdev_file, bool readonly, 581 struct rnbd_srv_dev *srv_dev) 582 { 583 struct rnbd_srv_sess_dev *sdev = rnbd_sess_dev_alloc(srv_sess); 584 585 if (IS_ERR(sdev)) 586 return sdev; 587 588 kref_init(&sdev->kref); 589 590 strscpy(sdev->pathname, open_msg->dev_name, sizeof(sdev->pathname)); 591 592 sdev->bdev_file = bdev_file; 593 sdev->sess = srv_sess; 594 sdev->dev = srv_dev; 595 sdev->readonly = readonly; 596 sdev->access_mode = open_msg->access_mode; 597 598 return sdev; 599 } 600 601 static char *rnbd_srv_get_full_path(struct rnbd_srv_session *srv_sess, 602 const char *dev_name) 603 { 604 char *full_path; 605 char *a, *b; 606 int len; 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 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 } else { 623 len = snprintf(full_path, PATH_MAX, "%s/%s", 624 dev_search_path, dev_name); 625 } 626 if (len >= PATH_MAX) { 627 pr_err("Too long path: %s, %s, %s\n", 628 dev_search_path, srv_sess->sessname, dev_name); 629 kfree(full_path); 630 return ERR_PTR(-EINVAL); 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 void 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 memset(rsp, 0, sizeof(*rsp)); 663 rsp->hdr.type = cpu_to_le16(RNBD_MSG_SESS_INFO_RSP); 664 rsp->ver = srv_sess->ver; 665 } 666 667 /** 668 * find_srv_sess_dev() - a dev is already opened by this name 669 * @srv_sess: the session to search. 670 * @dev_name: string containing the name of the device. 671 * 672 * Return struct rnbd_srv_sess_dev if srv_sess already opened the dev_name 673 * NULL if the session didn't open the device yet. 674 */ 675 static struct rnbd_srv_sess_dev * 676 find_srv_sess_dev(struct rnbd_srv_session *srv_sess, const char *dev_name) 677 { 678 struct rnbd_srv_sess_dev *sess_dev; 679 unsigned long index; 680 681 if (xa_empty(&srv_sess->index_idr)) 682 return NULL; 683 684 xa_for_each(&srv_sess->index_idr, index, sess_dev) 685 if (!strcmp(sess_dev->pathname, dev_name)) 686 return sess_dev; 687 688 return NULL; 689 } 690 691 static int process_msg_open(struct rnbd_srv_session *srv_sess, 692 const void *msg, size_t len, 693 void *data, size_t datalen) 694 { 695 int ret; 696 struct rnbd_srv_dev *srv_dev; 697 struct rnbd_srv_sess_dev *srv_sess_dev; 698 const struct rnbd_msg_open *open_msg = msg; 699 struct file *bdev_file; 700 blk_mode_t open_flags = BLK_OPEN_READ; 701 char *full_path; 702 struct rnbd_msg_open_rsp *rsp = data; 703 704 trace_process_msg_open(srv_sess, open_msg); 705 706 if (open_msg->access_mode != RNBD_ACCESS_RO) 707 open_flags |= BLK_OPEN_WRITE; 708 709 mutex_lock(&srv_sess->lock); 710 711 srv_sess_dev = find_srv_sess_dev(srv_sess, open_msg->dev_name); 712 if (srv_sess_dev) 713 goto fill_response; 714 715 if ((strlen(dev_search_path) + strlen(open_msg->dev_name)) 716 >= PATH_MAX) { 717 pr_err("Opening device for session %s failed, device path too long. '%s/%s' is longer than PATH_MAX (%d)\n", 718 srv_sess->sessname, dev_search_path, open_msg->dev_name, 719 PATH_MAX); 720 ret = -EINVAL; 721 goto reject; 722 } 723 if (strstr(open_msg->dev_name, "..")) { 724 pr_err("Opening device for session %s failed, device path %s contains relative path ..\n", 725 srv_sess->sessname, open_msg->dev_name); 726 ret = -EINVAL; 727 goto reject; 728 } 729 full_path = rnbd_srv_get_full_path(srv_sess, open_msg->dev_name); 730 if (IS_ERR(full_path)) { 731 ret = PTR_ERR(full_path); 732 pr_err("Opening device '%s' for client %s failed, failed to get device full path, err: %pe\n", 733 open_msg->dev_name, srv_sess->sessname, full_path); 734 goto reject; 735 } 736 737 bdev_file = bdev_file_open_by_path(full_path, open_flags, NULL, NULL); 738 if (IS_ERR(bdev_file)) { 739 ret = PTR_ERR(bdev_file); 740 pr_err("Opening device '%s' on session %s failed, failed to open the block device, err: %pe\n", 741 full_path, srv_sess->sessname, bdev_file); 742 goto free_path; 743 } 744 745 srv_dev = rnbd_srv_get_or_create_srv_dev(file_bdev(bdev_file), srv_sess, 746 open_msg->access_mode); 747 if (IS_ERR(srv_dev)) { 748 pr_err("Opening device '%s' on session %s failed, creating srv_dev failed, err: %pe\n", 749 full_path, srv_sess->sessname, srv_dev); 750 ret = PTR_ERR(srv_dev); 751 goto blkdev_put; 752 } 753 754 srv_sess_dev = rnbd_srv_create_set_sess_dev(srv_sess, open_msg, 755 bdev_file, 756 open_msg->access_mode == RNBD_ACCESS_RO, 757 srv_dev); 758 if (IS_ERR(srv_sess_dev)) { 759 pr_err("Opening device '%s' on session %s failed, creating sess_dev failed, err: %pe\n", 760 full_path, srv_sess->sessname, srv_sess_dev); 761 ret = PTR_ERR(srv_sess_dev); 762 goto srv_dev_put; 763 } 764 765 /* Create the srv_dev sysfs files if they haven't been created yet. The 766 * reason to delay the creation is not to create the sysfs files before 767 * we are sure the device can be opened. 768 */ 769 mutex_lock(&srv_dev->lock); 770 if (!srv_dev->dev_kobj.state_in_sysfs) { 771 ret = rnbd_srv_create_dev_sysfs(srv_dev, file_bdev(bdev_file)); 772 if (ret) { 773 mutex_unlock(&srv_dev->lock); 774 rnbd_srv_err(srv_sess_dev, 775 "Opening device failed, failed to create device sysfs files, err: %d\n", 776 ret); 777 goto free_srv_sess_dev; 778 } 779 } 780 781 ret = rnbd_srv_create_dev_session_sysfs(srv_sess_dev); 782 if (ret) { 783 mutex_unlock(&srv_dev->lock); 784 rnbd_srv_err(srv_sess_dev, 785 "Opening device failed, failed to create dev client sysfs files, err: %d\n", 786 ret); 787 goto free_srv_sess_dev; 788 } 789 790 list_add(&srv_sess_dev->dev_list, &srv_dev->sess_dev_list); 791 mutex_unlock(&srv_dev->lock); 792 793 rnbd_srv_info(srv_sess_dev, "Opened device '%s'\n", srv_dev->name); 794 795 kfree(full_path); 796 797 fill_response: 798 rnbd_srv_fill_msg_open_rsp(rsp, srv_sess_dev); 799 mutex_unlock(&srv_sess->lock); 800 return 0; 801 802 free_srv_sess_dev: 803 xa_erase(&srv_sess->index_idr, srv_sess_dev->device_id); 804 synchronize_rcu(); 805 kfree(srv_sess_dev); 806 srv_dev_put: 807 if (open_msg->access_mode != RNBD_ACCESS_RO) { 808 mutex_lock(&srv_dev->lock); 809 srv_dev->open_write_cnt--; 810 mutex_unlock(&srv_dev->lock); 811 } 812 rnbd_put_srv_dev(srv_dev); 813 blkdev_put: 814 fput(bdev_file); 815 free_path: 816 kfree(full_path); 817 reject: 818 mutex_unlock(&srv_sess->lock); 819 return ret; 820 } 821 822 static struct rtrs_srv_ctx *rtrs_ctx; 823 824 static struct rtrs_srv_ops rtrs_ops; 825 static int __init rnbd_srv_init_module(void) 826 { 827 int err = 0; 828 829 BUILD_BUG_ON(sizeof(struct rnbd_msg_hdr) != 4); 830 BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info) != 36); 831 BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info_rsp) != 36); 832 BUILD_BUG_ON(sizeof(struct rnbd_msg_open) != 264); 833 BUILD_BUG_ON(sizeof(struct rnbd_msg_close) != 8); 834 BUILD_BUG_ON(sizeof(struct rnbd_msg_open_rsp) != 56); 835 rtrs_ops = (struct rtrs_srv_ops) { 836 .rdma_ev = rnbd_srv_rdma_ev, 837 .link_ev = rnbd_srv_link_ev, 838 }; 839 rtrs_ctx = rtrs_srv_open(&rtrs_ops, port_nr); 840 if (IS_ERR(rtrs_ctx)) { 841 pr_err("rtrs_srv_open(), err: %pe\n", rtrs_ctx); 842 return PTR_ERR(rtrs_ctx); 843 } 844 845 err = rnbd_srv_create_sysfs_files(); 846 if (err) { 847 pr_err("rnbd_srv_create_sysfs_files(), err: %d\n", err); 848 rtrs_srv_close(rtrs_ctx); 849 } 850 851 return err; 852 } 853 854 static void __exit rnbd_srv_cleanup_module(void) 855 { 856 rtrs_srv_close(rtrs_ctx); 857 WARN_ON(!list_empty(&sess_list)); 858 rnbd_srv_destroy_sysfs_files(); 859 } 860 861 module_init(rnbd_srv_init_module); 862 module_exit(rnbd_srv_cleanup_module); 863