ceph_common.c 15 KB

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  1. #include <linux/ceph/ceph_debug.h>
  2. #include <linux/backing-dev.h>
  3. #include <linux/ctype.h>
  4. #include <linux/fs.h>
  5. #include <linux/inet.h>
  6. #include <linux/in6.h>
  7. #include <linux/key.h>
  8. #include <keys/ceph-type.h>
  9. #include <linux/module.h>
  10. #include <linux/mount.h>
  11. #include <linux/parser.h>
  12. #include <linux/sched.h>
  13. #include <linux/seq_file.h>
  14. #include <linux/slab.h>
  15. #include <linux/statfs.h>
  16. #include <linux/string.h>
  17. #include <linux/vmalloc.h>
  18. #include <linux/nsproxy.h>
  19. #include <net/net_namespace.h>
  20. #include <linux/ceph/ceph_features.h>
  21. #include <linux/ceph/libceph.h>
  22. #include <linux/ceph/debugfs.h>
  23. #include <linux/ceph/decode.h>
  24. #include <linux/ceph/mon_client.h>
  25. #include <linux/ceph/auth.h>
  26. #include "crypto.h"
  27. /*
  28. * Module compatibility interface. For now it doesn't do anything,
  29. * but its existence signals a certain level of functionality.
  30. *
  31. * The data buffer is used to pass information both to and from
  32. * libceph. The return value indicates whether libceph determines
  33. * it is compatible with the caller (from another kernel module),
  34. * given the provided data.
  35. *
  36. * The data pointer can be null.
  37. */
  38. bool libceph_compatible(void *data)
  39. {
  40. return true;
  41. }
  42. EXPORT_SYMBOL(libceph_compatible);
  43. /*
  44. * find filename portion of a path (/foo/bar/baz -> baz)
  45. */
  46. const char *ceph_file_part(const char *s, int len)
  47. {
  48. const char *e = s + len;
  49. while (e != s && *(e-1) != '/')
  50. e--;
  51. return e;
  52. }
  53. EXPORT_SYMBOL(ceph_file_part);
  54. const char *ceph_msg_type_name(int type)
  55. {
  56. switch (type) {
  57. case CEPH_MSG_SHUTDOWN: return "shutdown";
  58. case CEPH_MSG_PING: return "ping";
  59. case CEPH_MSG_AUTH: return "auth";
  60. case CEPH_MSG_AUTH_REPLY: return "auth_reply";
  61. case CEPH_MSG_MON_MAP: return "mon_map";
  62. case CEPH_MSG_MON_GET_MAP: return "mon_get_map";
  63. case CEPH_MSG_MON_SUBSCRIBE: return "mon_subscribe";
  64. case CEPH_MSG_MON_SUBSCRIBE_ACK: return "mon_subscribe_ack";
  65. case CEPH_MSG_STATFS: return "statfs";
  66. case CEPH_MSG_STATFS_REPLY: return "statfs_reply";
  67. case CEPH_MSG_MON_GET_VERSION: return "mon_get_version";
  68. case CEPH_MSG_MON_GET_VERSION_REPLY: return "mon_get_version_reply";
  69. case CEPH_MSG_MDS_MAP: return "mds_map";
  70. case CEPH_MSG_CLIENT_SESSION: return "client_session";
  71. case CEPH_MSG_CLIENT_RECONNECT: return "client_reconnect";
  72. case CEPH_MSG_CLIENT_REQUEST: return "client_request";
  73. case CEPH_MSG_CLIENT_REQUEST_FORWARD: return "client_request_forward";
  74. case CEPH_MSG_CLIENT_REPLY: return "client_reply";
  75. case CEPH_MSG_CLIENT_CAPS: return "client_caps";
  76. case CEPH_MSG_CLIENT_CAPRELEASE: return "client_cap_release";
  77. case CEPH_MSG_CLIENT_SNAP: return "client_snap";
  78. case CEPH_MSG_CLIENT_LEASE: return "client_lease";
  79. case CEPH_MSG_OSD_MAP: return "osd_map";
  80. case CEPH_MSG_OSD_OP: return "osd_op";
  81. case CEPH_MSG_OSD_OPREPLY: return "osd_opreply";
  82. case CEPH_MSG_WATCH_NOTIFY: return "watch_notify";
  83. default: return "unknown";
  84. }
  85. }
  86. EXPORT_SYMBOL(ceph_msg_type_name);
  87. /*
  88. * Initially learn our fsid, or verify an fsid matches.
  89. */
  90. int ceph_check_fsid(struct ceph_client *client, struct ceph_fsid *fsid)
  91. {
  92. if (client->have_fsid) {
  93. if (ceph_fsid_compare(&client->fsid, fsid)) {
  94. pr_err("bad fsid, had %pU got %pU",
  95. &client->fsid, fsid);
  96. return -1;
  97. }
  98. } else {
  99. memcpy(&client->fsid, fsid, sizeof(*fsid));
  100. }
  101. return 0;
  102. }
  103. EXPORT_SYMBOL(ceph_check_fsid);
  104. static int strcmp_null(const char *s1, const char *s2)
  105. {
  106. if (!s1 && !s2)
  107. return 0;
  108. if (s1 && !s2)
  109. return -1;
  110. if (!s1 && s2)
  111. return 1;
  112. return strcmp(s1, s2);
  113. }
  114. int ceph_compare_options(struct ceph_options *new_opt,
  115. struct ceph_client *client)
  116. {
  117. struct ceph_options *opt1 = new_opt;
  118. struct ceph_options *opt2 = client->options;
  119. int ofs = offsetof(struct ceph_options, mon_addr);
  120. int i;
  121. int ret;
  122. ret = memcmp(opt1, opt2, ofs);
  123. if (ret)
  124. return ret;
  125. ret = strcmp_null(opt1->name, opt2->name);
  126. if (ret)
  127. return ret;
  128. if (opt1->key && !opt2->key)
  129. return -1;
  130. if (!opt1->key && opt2->key)
  131. return 1;
  132. if (opt1->key && opt2->key) {
  133. if (opt1->key->type != opt2->key->type)
  134. return -1;
  135. if (opt1->key->created.tv_sec != opt2->key->created.tv_sec)
  136. return -1;
  137. if (opt1->key->created.tv_nsec != opt2->key->created.tv_nsec)
  138. return -1;
  139. if (opt1->key->len != opt2->key->len)
  140. return -1;
  141. if (opt1->key->key && !opt2->key->key)
  142. return -1;
  143. if (!opt1->key->key && opt2->key->key)
  144. return 1;
  145. if (opt1->key->key && opt2->key->key) {
  146. ret = memcmp(opt1->key->key, opt2->key->key, opt1->key->len);
  147. if (ret)
  148. return ret;
  149. }
  150. }
  151. /* any matching mon ip implies a match */
  152. for (i = 0; i < opt1->num_mon; i++) {
  153. if (ceph_monmap_contains(client->monc.monmap,
  154. &opt1->mon_addr[i]))
  155. return 0;
  156. }
  157. return -1;
  158. }
  159. EXPORT_SYMBOL(ceph_compare_options);
  160. void *ceph_kvmalloc(size_t size, gfp_t flags)
  161. {
  162. if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
  163. void *ptr = kmalloc(size, flags | __GFP_NOWARN);
  164. if (ptr)
  165. return ptr;
  166. }
  167. return __vmalloc(size, flags | __GFP_HIGHMEM, PAGE_KERNEL);
  168. }
  169. static int parse_fsid(const char *str, struct ceph_fsid *fsid)
  170. {
  171. int i = 0;
  172. char tmp[3];
  173. int err = -EINVAL;
  174. int d;
  175. dout("parse_fsid '%s'\n", str);
  176. tmp[2] = 0;
  177. while (*str && i < 16) {
  178. if (ispunct(*str)) {
  179. str++;
  180. continue;
  181. }
  182. if (!isxdigit(str[0]) || !isxdigit(str[1]))
  183. break;
  184. tmp[0] = str[0];
  185. tmp[1] = str[1];
  186. if (sscanf(tmp, "%x", &d) < 1)
  187. break;
  188. fsid->fsid[i] = d & 0xff;
  189. i++;
  190. str += 2;
  191. }
  192. if (i == 16)
  193. err = 0;
  194. dout("parse_fsid ret %d got fsid %pU", err, fsid);
  195. return err;
  196. }
  197. /*
  198. * ceph options
  199. */
  200. enum {
  201. Opt_osdtimeout,
  202. Opt_osdkeepalivetimeout,
  203. Opt_mount_timeout,
  204. Opt_osd_idle_ttl,
  205. Opt_last_int,
  206. /* int args above */
  207. Opt_fsid,
  208. Opt_name,
  209. Opt_secret,
  210. Opt_key,
  211. Opt_ip,
  212. Opt_last_string,
  213. /* string args above */
  214. Opt_share,
  215. Opt_noshare,
  216. Opt_crc,
  217. Opt_nocrc,
  218. Opt_cephx_require_signatures,
  219. Opt_nocephx_require_signatures,
  220. };
  221. static match_table_t opt_tokens = {
  222. {Opt_osdtimeout, "osdtimeout=%d"},
  223. {Opt_osdkeepalivetimeout, "osdkeepalive=%d"},
  224. {Opt_mount_timeout, "mount_timeout=%d"},
  225. {Opt_osd_idle_ttl, "osd_idle_ttl=%d"},
  226. /* int args above */
  227. {Opt_fsid, "fsid=%s"},
  228. {Opt_name, "name=%s"},
  229. {Opt_secret, "secret=%s"},
  230. {Opt_key, "key=%s"},
  231. {Opt_ip, "ip=%s"},
  232. /* string args above */
  233. {Opt_share, "share"},
  234. {Opt_noshare, "noshare"},
  235. {Opt_crc, "crc"},
  236. {Opt_nocrc, "nocrc"},
  237. {Opt_cephx_require_signatures, "cephx_require_signatures"},
  238. {Opt_nocephx_require_signatures, "nocephx_require_signatures"},
  239. {-1, NULL}
  240. };
  241. void ceph_destroy_options(struct ceph_options *opt)
  242. {
  243. dout("destroy_options %p\n", opt);
  244. kfree(opt->name);
  245. if (opt->key) {
  246. ceph_crypto_key_destroy(opt->key);
  247. kfree(opt->key);
  248. }
  249. kfree(opt->mon_addr);
  250. kfree(opt);
  251. }
  252. EXPORT_SYMBOL(ceph_destroy_options);
  253. /* get secret from key store */
  254. static int get_secret(struct ceph_crypto_key *dst, const char *name) {
  255. struct key *ukey;
  256. int key_err;
  257. int err = 0;
  258. struct ceph_crypto_key *ckey;
  259. ukey = request_key(&key_type_ceph, name, NULL);
  260. if (!ukey || IS_ERR(ukey)) {
  261. /* request_key errors don't map nicely to mount(2)
  262. errors; don't even try, but still printk */
  263. key_err = PTR_ERR(ukey);
  264. switch (key_err) {
  265. case -ENOKEY:
  266. pr_warn("ceph: Mount failed due to key not found: %s\n",
  267. name);
  268. break;
  269. case -EKEYEXPIRED:
  270. pr_warn("ceph: Mount failed due to expired key: %s\n",
  271. name);
  272. break;
  273. case -EKEYREVOKED:
  274. pr_warn("ceph: Mount failed due to revoked key: %s\n",
  275. name);
  276. break;
  277. default:
  278. pr_warn("ceph: Mount failed due to unknown key error %d: %s\n",
  279. key_err, name);
  280. }
  281. err = -EPERM;
  282. goto out;
  283. }
  284. ckey = ukey->payload.data;
  285. err = ceph_crypto_key_clone(dst, ckey);
  286. if (err)
  287. goto out_key;
  288. /* pass through, err is 0 */
  289. out_key:
  290. key_put(ukey);
  291. out:
  292. return err;
  293. }
  294. struct ceph_options *
  295. ceph_parse_options(char *options, const char *dev_name,
  296. const char *dev_name_end,
  297. int (*parse_extra_token)(char *c, void *private),
  298. void *private)
  299. {
  300. struct ceph_options *opt;
  301. const char *c;
  302. int err = -ENOMEM;
  303. substring_t argstr[MAX_OPT_ARGS];
  304. if (current->nsproxy->net_ns != &init_net)
  305. return ERR_PTR(-EINVAL);
  306. opt = kzalloc(sizeof(*opt), GFP_KERNEL);
  307. if (!opt)
  308. return ERR_PTR(-ENOMEM);
  309. opt->mon_addr = kcalloc(CEPH_MAX_MON, sizeof(*opt->mon_addr),
  310. GFP_KERNEL);
  311. if (!opt->mon_addr)
  312. goto out;
  313. dout("parse_options %p options '%s' dev_name '%s'\n", opt, options,
  314. dev_name);
  315. /* start with defaults */
  316. opt->flags = CEPH_OPT_DEFAULT;
  317. opt->osd_keepalive_timeout = CEPH_OSD_KEEPALIVE_DEFAULT;
  318. opt->mount_timeout = CEPH_MOUNT_TIMEOUT_DEFAULT; /* seconds */
  319. opt->osd_idle_ttl = CEPH_OSD_IDLE_TTL_DEFAULT; /* seconds */
  320. /* get mon ip(s) */
  321. /* ip1[:port1][,ip2[:port2]...] */
  322. err = ceph_parse_ips(dev_name, dev_name_end, opt->mon_addr,
  323. CEPH_MAX_MON, &opt->num_mon);
  324. if (err < 0)
  325. goto out;
  326. /* parse mount options */
  327. while ((c = strsep(&options, ",")) != NULL) {
  328. int token, intval, ret;
  329. if (!*c)
  330. continue;
  331. err = -EINVAL;
  332. token = match_token((char *)c, opt_tokens, argstr);
  333. if (token < 0 && parse_extra_token) {
  334. /* extra? */
  335. err = parse_extra_token((char *)c, private);
  336. if (err < 0) {
  337. pr_err("bad option at '%s'\n", c);
  338. goto out;
  339. }
  340. continue;
  341. }
  342. if (token < Opt_last_int) {
  343. ret = match_int(&argstr[0], &intval);
  344. if (ret < 0) {
  345. pr_err("bad mount option arg (not int) "
  346. "at '%s'\n", c);
  347. continue;
  348. }
  349. dout("got int token %d val %d\n", token, intval);
  350. } else if (token > Opt_last_int && token < Opt_last_string) {
  351. dout("got string token %d val %s\n", token,
  352. argstr[0].from);
  353. } else {
  354. dout("got token %d\n", token);
  355. }
  356. switch (token) {
  357. case Opt_ip:
  358. err = ceph_parse_ips(argstr[0].from,
  359. argstr[0].to,
  360. &opt->my_addr,
  361. 1, NULL);
  362. if (err < 0)
  363. goto out;
  364. opt->flags |= CEPH_OPT_MYIP;
  365. break;
  366. case Opt_fsid:
  367. err = parse_fsid(argstr[0].from, &opt->fsid);
  368. if (err == 0)
  369. opt->flags |= CEPH_OPT_FSID;
  370. break;
  371. case Opt_name:
  372. opt->name = kstrndup(argstr[0].from,
  373. argstr[0].to-argstr[0].from,
  374. GFP_KERNEL);
  375. break;
  376. case Opt_secret:
  377. opt->key = kzalloc(sizeof(*opt->key), GFP_KERNEL);
  378. if (!opt->key) {
  379. err = -ENOMEM;
  380. goto out;
  381. }
  382. err = ceph_crypto_key_unarmor(opt->key, argstr[0].from);
  383. if (err < 0)
  384. goto out;
  385. break;
  386. case Opt_key:
  387. opt->key = kzalloc(sizeof(*opt->key), GFP_KERNEL);
  388. if (!opt->key) {
  389. err = -ENOMEM;
  390. goto out;
  391. }
  392. err = get_secret(opt->key, argstr[0].from);
  393. if (err < 0)
  394. goto out;
  395. break;
  396. /* misc */
  397. case Opt_osdtimeout:
  398. pr_warn("ignoring deprecated osdtimeout option\n");
  399. break;
  400. case Opt_osdkeepalivetimeout:
  401. opt->osd_keepalive_timeout = intval;
  402. break;
  403. case Opt_osd_idle_ttl:
  404. opt->osd_idle_ttl = intval;
  405. break;
  406. case Opt_mount_timeout:
  407. opt->mount_timeout = intval;
  408. break;
  409. case Opt_share:
  410. opt->flags &= ~CEPH_OPT_NOSHARE;
  411. break;
  412. case Opt_noshare:
  413. opt->flags |= CEPH_OPT_NOSHARE;
  414. break;
  415. case Opt_crc:
  416. opt->flags &= ~CEPH_OPT_NOCRC;
  417. break;
  418. case Opt_nocrc:
  419. opt->flags |= CEPH_OPT_NOCRC;
  420. break;
  421. case Opt_cephx_require_signatures:
  422. opt->flags &= ~CEPH_OPT_NOMSGAUTH;
  423. break;
  424. case Opt_nocephx_require_signatures:
  425. opt->flags |= CEPH_OPT_NOMSGAUTH;
  426. break;
  427. default:
  428. BUG_ON(token);
  429. }
  430. }
  431. /* success */
  432. return opt;
  433. out:
  434. ceph_destroy_options(opt);
  435. return ERR_PTR(err);
  436. }
  437. EXPORT_SYMBOL(ceph_parse_options);
  438. u64 ceph_client_id(struct ceph_client *client)
  439. {
  440. return client->monc.auth->global_id;
  441. }
  442. EXPORT_SYMBOL(ceph_client_id);
  443. /*
  444. * create a fresh client instance
  445. */
  446. struct ceph_client *ceph_create_client(struct ceph_options *opt, void *private,
  447. u64 supported_features,
  448. u64 required_features)
  449. {
  450. struct ceph_client *client;
  451. struct ceph_entity_addr *myaddr = NULL;
  452. int err = -ENOMEM;
  453. client = kzalloc(sizeof(*client), GFP_KERNEL);
  454. if (client == NULL)
  455. return ERR_PTR(-ENOMEM);
  456. client->private = private;
  457. client->options = opt;
  458. mutex_init(&client->mount_mutex);
  459. init_waitqueue_head(&client->auth_wq);
  460. client->auth_err = 0;
  461. if (!ceph_test_opt(client, NOMSGAUTH))
  462. required_features |= CEPH_FEATURE_MSG_AUTH;
  463. client->extra_mon_dispatch = NULL;
  464. client->supported_features = CEPH_FEATURES_SUPPORTED_DEFAULT |
  465. supported_features;
  466. client->required_features = CEPH_FEATURES_REQUIRED_DEFAULT |
  467. required_features;
  468. /* msgr */
  469. if (ceph_test_opt(client, MYIP))
  470. myaddr = &client->options->my_addr;
  471. ceph_messenger_init(&client->msgr, myaddr,
  472. client->supported_features,
  473. client->required_features,
  474. ceph_test_opt(client, NOCRC));
  475. /* subsystems */
  476. err = ceph_monc_init(&client->monc, client);
  477. if (err < 0)
  478. goto fail;
  479. err = ceph_osdc_init(&client->osdc, client);
  480. if (err < 0)
  481. goto fail_monc;
  482. return client;
  483. fail_monc:
  484. ceph_monc_stop(&client->monc);
  485. fail:
  486. kfree(client);
  487. return ERR_PTR(err);
  488. }
  489. EXPORT_SYMBOL(ceph_create_client);
  490. void ceph_destroy_client(struct ceph_client *client)
  491. {
  492. dout("destroy_client %p\n", client);
  493. atomic_set(&client->msgr.stopping, 1);
  494. /* unmount */
  495. ceph_osdc_stop(&client->osdc);
  496. ceph_monc_stop(&client->monc);
  497. ceph_debugfs_client_cleanup(client);
  498. ceph_destroy_options(client->options);
  499. kfree(client);
  500. dout("destroy_client %p done\n", client);
  501. }
  502. EXPORT_SYMBOL(ceph_destroy_client);
  503. /*
  504. * true if we have the mon map (and have thus joined the cluster)
  505. */
  506. static int have_mon_and_osd_map(struct ceph_client *client)
  507. {
  508. return client->monc.monmap && client->monc.monmap->epoch &&
  509. client->osdc.osdmap && client->osdc.osdmap->epoch;
  510. }
  511. /*
  512. * mount: join the ceph cluster, and open root directory.
  513. */
  514. int __ceph_open_session(struct ceph_client *client, unsigned long started)
  515. {
  516. int err;
  517. unsigned long timeout = client->options->mount_timeout * HZ;
  518. /* open session, and wait for mon and osd maps */
  519. err = ceph_monc_open_session(&client->monc);
  520. if (err < 0)
  521. return err;
  522. while (!have_mon_and_osd_map(client)) {
  523. err = -EIO;
  524. if (timeout && time_after_eq(jiffies, started + timeout))
  525. return err;
  526. /* wait */
  527. dout("mount waiting for mon_map\n");
  528. err = wait_event_interruptible_timeout(client->auth_wq,
  529. have_mon_and_osd_map(client) || (client->auth_err < 0),
  530. timeout);
  531. if (err == -EINTR || err == -ERESTARTSYS)
  532. return err;
  533. if (client->auth_err < 0)
  534. return client->auth_err;
  535. }
  536. return 0;
  537. }
  538. EXPORT_SYMBOL(__ceph_open_session);
  539. int ceph_open_session(struct ceph_client *client)
  540. {
  541. int ret;
  542. unsigned long started = jiffies; /* note the start time */
  543. dout("open_session start\n");
  544. mutex_lock(&client->mount_mutex);
  545. ret = __ceph_open_session(client, started);
  546. mutex_unlock(&client->mount_mutex);
  547. return ret;
  548. }
  549. EXPORT_SYMBOL(ceph_open_session);
  550. static int __init init_ceph_lib(void)
  551. {
  552. int ret = 0;
  553. ret = ceph_debugfs_init();
  554. if (ret < 0)
  555. goto out;
  556. ret = ceph_crypto_init();
  557. if (ret < 0)
  558. goto out_debugfs;
  559. ret = ceph_msgr_init();
  560. if (ret < 0)
  561. goto out_crypto;
  562. ret = ceph_osdc_setup();
  563. if (ret < 0)
  564. goto out_msgr;
  565. pr_info("loaded (mon/osd proto %d/%d)\n",
  566. CEPH_MONC_PROTOCOL, CEPH_OSDC_PROTOCOL);
  567. return 0;
  568. out_msgr:
  569. ceph_msgr_exit();
  570. out_crypto:
  571. ceph_crypto_shutdown();
  572. out_debugfs:
  573. ceph_debugfs_cleanup();
  574. out:
  575. return ret;
  576. }
  577. static void __exit exit_ceph_lib(void)
  578. {
  579. dout("exit_ceph_lib\n");
  580. ceph_osdc_cleanup();
  581. ceph_msgr_exit();
  582. ceph_crypto_shutdown();
  583. ceph_debugfs_cleanup();
  584. }
  585. module_init(init_ceph_lib);
  586. module_exit(exit_ceph_lib);
  587. MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
  588. MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
  589. MODULE_AUTHOR("Patience Warnick <patience@newdream.net>");
  590. MODULE_DESCRIPTION("Ceph filesystem for Linux");
  591. MODULE_LICENSE("GPL");