drivers/block/rnbd/rnbd-clt-sysfs.c

   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
  10 #undef pr_fmt
  11 #define pr_fmt(fmt) KBUILD_MODNAME " L" __stringify(__LINE__) ": " fmt
  12
  13 #include <linux/types.h>
  14 #include <linux/ctype.h>
  15 #include <linux/parser.h>
  16 #include <linux/module.h>
  17 #include <linux/in6.h>
  18 #include <linux/fs.h>
  19 #include <linux/uaccess.h>
  20 #include <linux/device.h>
  21 #include <rdma/ib.h>
  22 #include <rdma/rdma_cm.h>
  23
  24 #include "rnbd-clt.h"
  25
  26 static struct device *rnbd_dev;
  27 static struct class *rnbd_dev_class;
  28 static struct kobject *rnbd_devs_kobj;
  29
  30 enum {
  31         RNBD_OPT_ERR            = 0,
  32         RNBD_OPT_DEST_PORT      = 1 << 0,
  33         RNBD_OPT_PATH           = 1 << 1,
  34         RNBD_OPT_DEV_PATH       = 1 << 2,
  35         RNBD_OPT_ACCESS_MODE    = 1 << 3,
  36         RNBD_OPT_SESSNAME       = 1 << 6,
  37 };
  38
  39 static const unsigned int rnbd_opt_mandatory[] = {
  40         RNBD_OPT_DEV_PATH,
  41         RNBD_OPT_SESSNAME,
  42 };
  43
  44 static const match_table_t rnbd_opt_tokens = {
  45         {RNBD_OPT_PATH,         "path=%s"       },
  46         {RNBD_OPT_DEV_PATH,     "device_path=%s"},
  47         {RNBD_OPT_DEST_PORT,    "dest_port=%d"  },
  48         {RNBD_OPT_ACCESS_MODE,  "access_mode=%s"},
  49         {RNBD_OPT_SESSNAME,     "sessname=%s"   },
  50         {RNBD_OPT_ERR,          NULL            },
  51 };
  52
  53 struct rnbd_map_options {
  54         char *sessname;
  55         struct rtrs_addr *paths;
  56         size_t *path_cnt;
  57         char *pathname;
  58         u16 *dest_port;
  59         enum rnbd_access_mode *access_mode;
  60 };
  61
  62 static int rnbd_clt_parse_map_options(const char *buf, size_t max_path_cnt,
  63                                        struct rnbd_map_options *opt)
  64 {
  65         char *options, *sep_opt;
  66         char *p;
  67         substring_t args[MAX_OPT_ARGS];
  68         int opt_mask = 0;
  69         int token;
  70         int ret = -EINVAL;
  71         int i, dest_port;
  72         int p_cnt = 0;
  73
  74         options = kstrdup(buf, GFP_KERNEL);
  75         if (!options)
  76                 return -ENOMEM;
  77
  78         sep_opt = strstrip(options);
  79         while ((p = strsep(&sep_opt, " ")) != NULL) {
  80                 if (!*p)
  81                         continue;
  82
  83                 token = match_token(p, rnbd_opt_tokens, args);
  84                 opt_mask |= token;
  85
  86                 switch (token) {
  87                 case RNBD_OPT_SESSNAME:
  88                         p = match_strdup(args);
  89                         if (!p) {
  90                                 ret = -ENOMEM;
  91                                 goto out;
  92                         }
  93                         if (strlen(p) > NAME_MAX) {
  94                                 pr_err("map_device: sessname too long\n");
  95                                 ret = -EINVAL;
  96                                 kfree(p);
  97                                 goto out;
  98                         }
  99                         strlcpy(opt->sessname, p, NAME_MAX);
 100                         kfree(p);
 101                         break;
 102
 103                 case RNBD_OPT_PATH:
 104                         if (p_cnt >= max_path_cnt) {
 105                                 pr_err("map_device: too many (> %zu) paths provided\n",
 106                                        max_path_cnt);
 107                                 ret = -ENOMEM;
 108                                 goto out;
 109                         }
 110                         p = match_strdup(args);
 111                         if (!p) {
 112                                 ret = -ENOMEM;
 113                                 goto out;
 114                         }
 115
 116                         ret = rtrs_addr_to_sockaddr(p, strlen(p),
 117                                                     *opt->dest_port,
 118                                                     &opt->paths[p_cnt]);
 119                         if (ret) {
 120                                 pr_err("Can't parse path %s: %d\n", p, ret);
 121                                 kfree(p);
 122                                 goto out;
 123                         }
 124
 125                         p_cnt++;
 126
 127                         kfree(p);
 128                         break;
 129
 130                 case RNBD_OPT_DEV_PATH:
 131                         p = match_strdup(args);
 132                         if (!p) {
 133                                 ret = -ENOMEM;
 134                                 goto out;
 135                         }
 136                         if (strlen(p) > NAME_MAX) {
 137                                 pr_err("map_device: Device path too long\n");
 138                                 ret = -EINVAL;
 139                                 kfree(p);
 140                                 goto out;
 141                         }
 142                         strlcpy(opt->pathname, p, NAME_MAX);
 143                         kfree(p);
 144                         break;
 145
 146                 case RNBD_OPT_DEST_PORT:
 147                         if (match_int(args, &dest_port) || dest_port < 0 ||
 148                             dest_port > 65535) {
 149                                 pr_err("bad destination port number parameter '%d'\n",
 150                                        dest_port);
 151                                 ret = -EINVAL;
 152                                 goto out;
 153                         }
 154                         *opt->dest_port = dest_port;
 155                         break;
 156
 157                 case RNBD_OPT_ACCESS_MODE:
 158                         p = match_strdup(args);
 159                         if (!p) {
 160                                 ret = -ENOMEM;
 161                                 goto out;
 162                         }
 163
 164                         if (!strcmp(p, "ro")) {
 165                                 *opt->access_mode = RNBD_ACCESS_RO;
 166                         } else if (!strcmp(p, "rw")) {
 167                                 *opt->access_mode = RNBD_ACCESS_RW;
 168                         } else if (!strcmp(p, "migration")) {
 169                                 *opt->access_mode = RNBD_ACCESS_MIGRATION;
 170                         } else {
 171                                 pr_err("map_device: Invalid access_mode: '%s'\n",
 172                                        p);
 173                                 ret = -EINVAL;
 174                                 kfree(p);
 175                                 goto out;
 176                         }
 177
 178                         kfree(p);
 179                         break;
 180
 181                 default:
 182                         pr_err("map_device: Unknown parameter or missing value '%s'\n",
 183                                p);
 184                         ret = -EINVAL;
 185                         goto out;
 186                 }
 187         }
 188
 189         for (i = 0; i < ARRAY_SIZE(rnbd_opt_mandatory); i++) {
 190                 if ((opt_mask & rnbd_opt_mandatory[i])) {
 191                         ret = 0;
 192                 } else {
 193                         pr_err("map_device: Parameters missing\n");
 194                         ret = -EINVAL;
 195                         break;
 196                 }
 197         }
 198
 199 out:
 200         *opt->path_cnt = p_cnt;
 201         kfree(options);
 202         return ret;
 203 }
 204
 205 static ssize_t state_show(struct kobject *kobj,
 206                           struct kobj_attribute *attr, char *page)
 207 {
 208         struct rnbd_clt_dev *dev;
 209
 210         dev = container_of(kobj, struct rnbd_clt_dev, kobj);
 211
 212         switch (dev->dev_state) {
 213         case DEV_STATE_INIT:
 214                 return snprintf(page, PAGE_SIZE, "init\n");
 215         case DEV_STATE_MAPPED:
 216                 /* TODO fix cli tool before changing to proper state */
 217                 return snprintf(page, PAGE_SIZE, "open\n");
 218         case DEV_STATE_MAPPED_DISCONNECTED:
 219                 /* TODO fix cli tool before changing to proper state */
 220                 return snprintf(page, PAGE_SIZE, "closed\n");
 221         case DEV_STATE_UNMAPPED:
 222                 return snprintf(page, PAGE_SIZE, "unmapped\n");
 223         default:
 224                 return snprintf(page, PAGE_SIZE, "unknown\n");
 225         }
 226 }
 227
 228 static struct kobj_attribute rnbd_clt_state_attr = __ATTR_RO(state);
 229
 230 static ssize_t mapping_path_show(struct kobject *kobj,
 231                                  struct kobj_attribute *attr, char *page)
 232 {
 233         struct rnbd_clt_dev *dev;
 234
 235         dev = container_of(kobj, struct rnbd_clt_dev, kobj);
 236
 237         return scnprintf(page, PAGE_SIZE, "%s\n", dev->pathname);
 238 }
 239
 240 static struct kobj_attribute rnbd_clt_mapping_path_attr =
 241         __ATTR_RO(mapping_path);
 242
 243 static ssize_t access_mode_show(struct kobject *kobj,
 244                                 struct kobj_attribute *attr, char *page)
 245 {
 246         struct rnbd_clt_dev *dev;
 247
 248         dev = container_of(kobj, struct rnbd_clt_dev, kobj);
 249
 250         return snprintf(page, PAGE_SIZE, "%s\n",
 251                         rnbd_access_mode_str(dev->access_mode));
 252 }
 253
 254 static struct kobj_attribute rnbd_clt_access_mode =
 255         __ATTR_RO(access_mode);
 256
 257 static ssize_t rnbd_clt_unmap_dev_show(struct kobject *kobj,
 258                                         struct kobj_attribute *attr, char *page)
 259 {
 260         return scnprintf(page, PAGE_SIZE, "Usage: echo <normal|force> > %s\n",
 261                          attr->attr.name);
 262 }
 263
 264 static ssize_t rnbd_clt_unmap_dev_store(struct kobject *kobj,
 265                                          struct kobj_attribute *attr,
 266                                          const char *buf, size_t count)
 267 {
 268         struct rnbd_clt_dev *dev;
 269         char *opt, *options;
 270         bool force;
 271         int err;
 272
 273         opt = kstrdup(buf, GFP_KERNEL);
 274         if (!opt)
 275                 return -ENOMEM;
 276
 277         options = strstrip(opt);
 278         dev = container_of(kobj, struct rnbd_clt_dev, kobj);
 279         if (sysfs_streq(options, "normal")) {
 280                 force = false;
 281         } else if (sysfs_streq(options, "force")) {
 282                 force = true;
 283         } else {
 284                 rnbd_clt_err(dev,
 285                               "unmap_device: Invalid value: %s\n",
 286                               options);
 287                 err = -EINVAL;
 288                 goto out;
 289         }
 290
 291         rnbd_clt_info(dev, "Unmapping device, option: %s.\n",
 292                        force ? "force" : "normal");
 293
 294         /*
 295          * We take explicit module reference only for one reason: do not
 296          * race with lockless rnbd_destroy_sessions().
 297          */
 298         if (!try_module_get(THIS_MODULE)) {
 299                 err = -ENODEV;
 300                 goto out;
 301         }
 302         err = rnbd_clt_unmap_device(dev, force, &attr->attr);
 303         if (err) {
 304                 if (err != -EALREADY)
 305                         rnbd_clt_err(dev, "unmap_device: %d\n",  err);
 306                 goto module_put;
 307         }
 308
 309         /*
 310          * Here device can be vanished!
 311          */
 312
 313         err = count;
 314
 315 module_put:
 316         module_put(THIS_MODULE);
 317 out:
 318         kfree(opt);
 319
 320         return err;
 321 }
 322
 323 static struct kobj_attribute rnbd_clt_unmap_device_attr =
 324         __ATTR(unmap_device, 0644, rnbd_clt_unmap_dev_show,
 325                rnbd_clt_unmap_dev_store);
 326
 327 static ssize_t rnbd_clt_resize_dev_show(struct kobject *kobj,
 328                                          struct kobj_attribute *attr,
 329                                          char *page)
 330 {
 331         return scnprintf(page, PAGE_SIZE,
 332                          "Usage: echo <new size in sectors> > %s\n",
 333                          attr->attr.name);
 334 }
 335
 336 static ssize_t rnbd_clt_resize_dev_store(struct kobject *kobj,
 337                                           struct kobj_attribute *attr,
 338                                           const char *buf, size_t count)
 339 {
 340         int ret;
 341         unsigned long sectors;
 342         struct rnbd_clt_dev *dev;
 343
 344         dev = container_of(kobj, struct rnbd_clt_dev, kobj);
 345
 346         ret = kstrtoul(buf, 0, &sectors);
 347         if (ret)
 348                 return ret;
 349
 350         ret = rnbd_clt_resize_disk(dev, (size_t)sectors);
 351         if (ret)
 352                 return ret;
 353
 354         return count;
 355 }
 356
 357 static struct kobj_attribute rnbd_clt_resize_dev_attr =
 358         __ATTR(resize, 0644, rnbd_clt_resize_dev_show,
 359                rnbd_clt_resize_dev_store);
 360
 361 static ssize_t rnbd_clt_remap_dev_show(struct kobject *kobj,
 362                                         struct kobj_attribute *attr, char *page)
 363 {
 364         return scnprintf(page, PAGE_SIZE, "Usage: echo <1> > %s\n",
 365                          attr->attr.name);
 366 }
 367
 368 static ssize_t rnbd_clt_remap_dev_store(struct kobject *kobj,
 369                                          struct kobj_attribute *attr,
 370                                          const char *buf, size_t count)
 371 {
 372         struct rnbd_clt_dev *dev;
 373         char *opt, *options;
 374         int err;
 375
 376         opt = kstrdup(buf, GFP_KERNEL);
 377         if (!opt)
 378                 return -ENOMEM;
 379
 380         options = strstrip(opt);
 381         dev = container_of(kobj, struct rnbd_clt_dev, kobj);
 382         if (!sysfs_streq(options, "1")) {
 383                 rnbd_clt_err(dev,
 384                               "remap_device: Invalid value: %s\n",
 385                               options);
 386                 err = -EINVAL;
 387                 goto out;
 388         }
 389         err = rnbd_clt_remap_device(dev);
 390         if (likely(!err))
 391                 err = count;
 392
 393 out:
 394         kfree(opt);
 395
 396         return err;
 397 }
 398
 399 static struct kobj_attribute rnbd_clt_remap_device_attr =
 400         __ATTR(remap_device, 0644, rnbd_clt_remap_dev_show,
 401                rnbd_clt_remap_dev_store);
 402
 403 static ssize_t session_show(struct kobject *kobj, struct kobj_attribute *attr,
 404                             char *page)
 405 {
 406         struct rnbd_clt_dev *dev;
 407
 408         dev = container_of(kobj, struct rnbd_clt_dev, kobj);
 409
 410         return scnprintf(page, PAGE_SIZE, "%s\n", dev->sess->sessname);
 411 }
 412
 413 static struct kobj_attribute rnbd_clt_session_attr =
 414         __ATTR_RO(session);
 415
 416 static struct attribute *rnbd_dev_attrs[] = {
 417         &rnbd_clt_unmap_device_attr.attr,
 418         &rnbd_clt_resize_dev_attr.attr,
 419         &rnbd_clt_remap_device_attr.attr,
 420         &rnbd_clt_mapping_path_attr.attr,
 421         &rnbd_clt_state_attr.attr,
 422         &rnbd_clt_session_attr.attr,
 423         &rnbd_clt_access_mode.attr,
 424         NULL,
 425 };
 426
 427 void rnbd_clt_remove_dev_symlink(struct rnbd_clt_dev *dev)
 428 {
 429         /*
 430          * The module unload rnbd_client_exit path is racing with unmapping of
 431          * the last single device from the sysfs manually
 432          * i.e. rnbd_clt_unmap_dev_store() leading to a sysfs warning because
 433          * of sysfs link already was removed already.
 434          */
 435         if (strlen(dev->blk_symlink_name) && try_module_get(THIS_MODULE)) {
 436                 sysfs_remove_link(rnbd_devs_kobj, dev->blk_symlink_name);
 437                 kfree(dev->blk_symlink_name);
 438                 module_put(THIS_MODULE);
 439         }
 440 }
 441
 442 static struct kobj_type rnbd_dev_ktype = {
 443         .sysfs_ops      = &kobj_sysfs_ops,
 444         .default_attrs  = rnbd_dev_attrs,
 445 };
 446
 447 static int rnbd_clt_add_dev_kobj(struct rnbd_clt_dev *dev)
 448 {
 449         int ret;
 450         struct kobject *gd_kobj = &disk_to_dev(dev->gd)->kobj;
 451
 452         ret = kobject_init_and_add(&dev->kobj, &rnbd_dev_ktype, gd_kobj, "%s",
 453                                    "rnbd");
 454         if (ret) {
 455                 rnbd_clt_err(dev, "Failed to create device sysfs dir, err: %d\n",
 456                               ret);
 457                 kobject_put(&dev->kobj);
 458         }
 459
 460         return ret;
 461 }
 462
 463 static ssize_t rnbd_clt_map_device_show(struct kobject *kobj,
 464                                          struct kobj_attribute *attr,
 465                                          char *page)
 466 {
 467         return scnprintf(page, PAGE_SIZE,
 468                          "Usage: echo \"[dest_port=server port number] sessname=<name of the rtrs session> path=<[srcaddr@]dstaddr> [path=<[srcaddr@]dstaddr>] device_path=<full path on remote side> [access_mode=<ro|rw|migration>]\" > %s\n\naddr ::= [ ip:<ipv4> | ip:<ipv6> | gid:<gid> ]\n",
 469                          attr->attr.name);
 470 }
 471
 472 static int rnbd_clt_get_path_name(struct rnbd_clt_dev *dev, char *buf,
 473                                    size_t len)
 474 {
 475         int ret;
 476         char pathname[NAME_MAX], *s;
 477
 478         strlcpy(pathname, dev->pathname, sizeof(pathname));
 479         while ((s = strchr(pathname, '/')))
 480                 s[0] = '!';
 481
 482         ret = snprintf(buf, len, "%s", pathname);
 483         if (ret >= len)
 484                 return -ENAMETOOLONG;
 485
 486         ret = snprintf(buf, len, "%s@%s", buf, dev->sess->sessname);
 487         if (ret >= len)
 488                 return -ENAMETOOLONG;
 489
 490         return 0;
 491 }
 492
 493 static int rnbd_clt_add_dev_symlink(struct rnbd_clt_dev *dev)
 494 {
 495         struct kobject *gd_kobj = &disk_to_dev(dev->gd)->kobj;
 496         int ret, len;
 497
 498         len = strlen(dev->pathname) + strlen(dev->sess->sessname) + 2;
 499         dev->blk_symlink_name = kzalloc(len, GFP_KERNEL);
 500         if (!dev->blk_symlink_name) {
 501                 rnbd_clt_err(dev, "Failed to allocate memory for blk_symlink_name\n");
 502                 return -ENOMEM;
 503         }
 504
 505         ret = rnbd_clt_get_path_name(dev, dev->blk_symlink_name,
 506                                       len);
 507         if (ret) {
 508                 rnbd_clt_err(dev, "Failed to get /sys/block symlink path, err: %d\n",
 509                               ret);
 510                 goto out_err;
 511         }
 512
 513         ret = sysfs_create_link(rnbd_devs_kobj, gd_kobj,
 514                                 dev->blk_symlink_name);
 515         if (ret) {
 516                 rnbd_clt_err(dev, "Creating /sys/block symlink failed, err: %d\n",
 517                               ret);
 518                 goto out_err;
 519         }
 520
 521         return 0;
 522
 523 out_err:
 524         dev->blk_symlink_name[0] = '\0';
 525         return ret;
 526 }
 527
 528 static ssize_t rnbd_clt_map_device_store(struct kobject *kobj,
 529                                           struct kobj_attribute *attr,
 530                                           const char *buf, size_t count)
 531 {
 532         struct rnbd_clt_dev *dev;
 533         struct rnbd_map_options opt;
 534         int ret;
 535         char pathname[NAME_MAX];
 536         char sessname[NAME_MAX];
 537         enum rnbd_access_mode access_mode = RNBD_ACCESS_RW;
 538         u16 port_nr = RTRS_PORT;
 539
 540         struct sockaddr_storage *addrs;
 541         struct rtrs_addr paths[6];
 542         size_t path_cnt;
 543
 544         opt.sessname = sessname;
 545         opt.paths = paths;
 546         opt.path_cnt = &path_cnt;
 547         opt.pathname = pathname;
 548         opt.dest_port = &port_nr;
 549         opt.access_mode = &access_mode;
 550         addrs = kcalloc(ARRAY_SIZE(paths) * 2, sizeof(*addrs), GFP_KERNEL);
 551         if (!addrs)
 552                 return -ENOMEM;
 553
 554         for (path_cnt = 0; path_cnt < ARRAY_SIZE(paths); path_cnt++) {
 555                 paths[path_cnt].src = &addrs[path_cnt * 2];
 556                 paths[path_cnt].dst = &addrs[path_cnt * 2 + 1];
 557         }
 558
 559         ret = rnbd_clt_parse_map_options(buf, ARRAY_SIZE(paths), &opt);
 560         if (ret)
 561                 goto out;
 562
 563         pr_info("Mapping device %s on session %s, (access_mode: %s)\n",
 564                 pathname, sessname,
 565                 rnbd_access_mode_str(access_mode));
 566
 567         dev = rnbd_clt_map_device(sessname, paths, path_cnt, port_nr, pathname,
 568                                   access_mode);
 569         if (IS_ERR(dev)) {
 570                 ret = PTR_ERR(dev);
 571                 goto out;
 572         }
 573
 574         ret = rnbd_clt_add_dev_kobj(dev);
 575         if (ret)
 576                 goto unmap_dev;
 577
 578         ret = rnbd_clt_add_dev_symlink(dev);
 579         if (ret)
 580                 goto unmap_dev;
 581
 582         kfree(addrs);
 583         return count;
 584
 585 unmap_dev:
 586         rnbd_clt_unmap_device(dev, true, NULL);
 587 out:
 588         kfree(addrs);
 589         return ret;
 590 }
 591
 592 static struct kobj_attribute rnbd_clt_map_device_attr =
 593         __ATTR(map_device, 0644,
 594                rnbd_clt_map_device_show, rnbd_clt_map_device_store);
 595
 596 static struct attribute *default_attrs[] = {
 597         &rnbd_clt_map_device_attr.attr,
 598         NULL,
 599 };
 600
 601 static struct attribute_group default_attr_group = {
 602         .attrs = default_attrs,
 603 };
 604
 605 static const struct attribute_group *default_attr_groups[] = {
 606         &default_attr_group,
 607         NULL,
 608 };
 609
 610 int rnbd_clt_create_sysfs_files(void)
 611 {
 612         int err;
 613
 614         rnbd_dev_class = class_create(THIS_MODULE, "rnbd-client");
 615         if (IS_ERR(rnbd_dev_class))
 616                 return PTR_ERR(rnbd_dev_class);
 617
 618         rnbd_dev = device_create_with_groups(rnbd_dev_class, NULL,
 619                                               MKDEV(0, 0), NULL,
 620                                               default_attr_groups, "ctl");
 621         if (IS_ERR(rnbd_dev)) {
 622                 err = PTR_ERR(rnbd_dev);
 623                 goto cls_destroy;
 624         }
 625         rnbd_devs_kobj = kobject_create_and_add("devices", &rnbd_dev->kobj);
 626         if (!rnbd_devs_kobj) {
 627                 err = -ENOMEM;
 628                 goto dev_destroy;
 629         }
 630
 631         return 0;
 632
 633 dev_destroy:
 634         device_destroy(rnbd_dev_class, MKDEV(0, 0));
 635 cls_destroy:
 636         class_destroy(rnbd_dev_class);
 637
 638         return err;
 639 }
 640
 641 void rnbd_clt_destroy_default_group(void)
 642 {
 643         sysfs_remove_group(&rnbd_dev->kobj, &default_attr_group);
 644 }
 645
 646 void rnbd_clt_destroy_sysfs_files(void)
 647 {
 648         kobject_del(rnbd_devs_kobj);
 649         kobject_put(rnbd_devs_kobj);
 650         device_destroy(rnbd_dev_class, MKDEV(0, 0));
 651         class_destroy(rnbd_dev_class);
 652 }