xref: /openbmc/linux/fs/ceph/super.c (revision f94909ce)
1 // SPDX-License-Identifier: GPL-2.0-only
2 
3 #include <linux/ceph/ceph_debug.h>
4 
5 #include <linux/backing-dev.h>
6 #include <linux/ctype.h>
7 #include <linux/fs.h>
8 #include <linux/inet.h>
9 #include <linux/in6.h>
10 #include <linux/module.h>
11 #include <linux/mount.h>
12 #include <linux/fs_context.h>
13 #include <linux/fs_parser.h>
14 #include <linux/sched.h>
15 #include <linux/seq_file.h>
16 #include <linux/slab.h>
17 #include <linux/statfs.h>
18 #include <linux/string.h>
19 
20 #include "super.h"
21 #include "mds_client.h"
22 #include "cache.h"
23 
24 #include <linux/ceph/ceph_features.h>
25 #include <linux/ceph/decode.h>
26 #include <linux/ceph/mon_client.h>
27 #include <linux/ceph/auth.h>
28 #include <linux/ceph/debugfs.h>
29 
30 static DEFINE_SPINLOCK(ceph_fsc_lock);
31 static LIST_HEAD(ceph_fsc_list);
32 
33 /*
34  * Ceph superblock operations
35  *
36  * Handle the basics of mounting, unmounting.
37  */
38 
39 /*
40  * super ops
41  */
42 static void ceph_put_super(struct super_block *s)
43 {
44 	struct ceph_fs_client *fsc = ceph_sb_to_client(s);
45 
46 	dout("put_super\n");
47 	ceph_mdsc_close_sessions(fsc->mdsc);
48 }
49 
50 static int ceph_statfs(struct dentry *dentry, struct kstatfs *buf)
51 {
52 	struct ceph_fs_client *fsc = ceph_inode_to_client(d_inode(dentry));
53 	struct ceph_mon_client *monc = &fsc->client->monc;
54 	struct ceph_statfs st;
55 	int i, err;
56 	u64 data_pool;
57 
58 	if (fsc->mdsc->mdsmap->m_num_data_pg_pools == 1) {
59 		data_pool = fsc->mdsc->mdsmap->m_data_pg_pools[0];
60 	} else {
61 		data_pool = CEPH_NOPOOL;
62 	}
63 
64 	dout("statfs\n");
65 	err = ceph_monc_do_statfs(monc, data_pool, &st);
66 	if (err < 0)
67 		return err;
68 
69 	/* fill in kstatfs */
70 	buf->f_type = CEPH_SUPER_MAGIC;  /* ?? */
71 
72 	/*
73 	 * express utilization in terms of large blocks to avoid
74 	 * overflow on 32-bit machines.
75 	 *
76 	 * NOTE: for the time being, we make bsize == frsize to humor
77 	 * not-yet-ancient versions of glibc that are broken.
78 	 * Someday, we will probably want to report a real block
79 	 * size...  whatever that may mean for a network file system!
80 	 */
81 	buf->f_bsize = 1 << CEPH_BLOCK_SHIFT;
82 	buf->f_frsize = 1 << CEPH_BLOCK_SHIFT;
83 
84 	/*
85 	 * By default use root quota for stats; fallback to overall filesystem
86 	 * usage if using 'noquotadf' mount option or if the root dir doesn't
87 	 * have max_bytes quota set.
88 	 */
89 	if (ceph_test_mount_opt(fsc, NOQUOTADF) ||
90 	    !ceph_quota_update_statfs(fsc, buf)) {
91 		buf->f_blocks = le64_to_cpu(st.kb) >> (CEPH_BLOCK_SHIFT-10);
92 		buf->f_bfree = le64_to_cpu(st.kb_avail) >> (CEPH_BLOCK_SHIFT-10);
93 		buf->f_bavail = le64_to_cpu(st.kb_avail) >> (CEPH_BLOCK_SHIFT-10);
94 	}
95 
96 	buf->f_files = le64_to_cpu(st.num_objects);
97 	buf->f_ffree = -1;
98 	buf->f_namelen = NAME_MAX;
99 
100 	/* Must convert the fsid, for consistent values across arches */
101 	buf->f_fsid.val[0] = 0;
102 	mutex_lock(&monc->mutex);
103 	for (i = 0 ; i < sizeof(monc->monmap->fsid) / sizeof(__le32) ; ++i)
104 		buf->f_fsid.val[0] ^= le32_to_cpu(((__le32 *)&monc->monmap->fsid)[i]);
105 	mutex_unlock(&monc->mutex);
106 
107 	/* fold the fs_cluster_id into the upper bits */
108 	buf->f_fsid.val[1] = monc->fs_cluster_id;
109 
110 	return 0;
111 }
112 
113 static int ceph_sync_fs(struct super_block *sb, int wait)
114 {
115 	struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
116 
117 	if (!wait) {
118 		dout("sync_fs (non-blocking)\n");
119 		ceph_flush_dirty_caps(fsc->mdsc);
120 		dout("sync_fs (non-blocking) done\n");
121 		return 0;
122 	}
123 
124 	dout("sync_fs (blocking)\n");
125 	ceph_osdc_sync(&fsc->client->osdc);
126 	ceph_mdsc_sync(fsc->mdsc);
127 	dout("sync_fs (blocking) done\n");
128 	return 0;
129 }
130 
131 /*
132  * mount options
133  */
134 enum {
135 	Opt_wsize,
136 	Opt_rsize,
137 	Opt_rasize,
138 	Opt_caps_wanted_delay_min,
139 	Opt_caps_wanted_delay_max,
140 	Opt_caps_max,
141 	Opt_readdir_max_entries,
142 	Opt_readdir_max_bytes,
143 	Opt_congestion_kb,
144 	/* int args above */
145 	Opt_snapdirname,
146 	Opt_mds_namespace,
147 	Opt_recover_session,
148 	Opt_source,
149 	/* string args above */
150 	Opt_dirstat,
151 	Opt_rbytes,
152 	Opt_asyncreaddir,
153 	Opt_dcache,
154 	Opt_ino32,
155 	Opt_fscache,
156 	Opt_poolperm,
157 	Opt_require_active_mds,
158 	Opt_acl,
159 	Opt_quotadf,
160 	Opt_copyfrom,
161 	Opt_wsync,
162 };
163 
164 enum ceph_recover_session_mode {
165 	ceph_recover_session_no,
166 	ceph_recover_session_clean
167 };
168 
169 static const struct constant_table ceph_param_recover[] = {
170 	{ "no",		ceph_recover_session_no },
171 	{ "clean",	ceph_recover_session_clean },
172 	{}
173 };
174 
175 static const struct fs_parameter_spec ceph_mount_parameters[] = {
176 	fsparam_flag_no ("acl",				Opt_acl),
177 	fsparam_flag_no ("asyncreaddir",		Opt_asyncreaddir),
178 	fsparam_s32	("caps_max",			Opt_caps_max),
179 	fsparam_u32	("caps_wanted_delay_max",	Opt_caps_wanted_delay_max),
180 	fsparam_u32	("caps_wanted_delay_min",	Opt_caps_wanted_delay_min),
181 	fsparam_u32	("write_congestion_kb",		Opt_congestion_kb),
182 	fsparam_flag_no ("copyfrom",			Opt_copyfrom),
183 	fsparam_flag_no ("dcache",			Opt_dcache),
184 	fsparam_flag_no ("dirstat",			Opt_dirstat),
185 	fsparam_flag_no	("fsc",				Opt_fscache), // fsc|nofsc
186 	fsparam_string	("fsc",				Opt_fscache), // fsc=...
187 	fsparam_flag_no ("ino32",			Opt_ino32),
188 	fsparam_string	("mds_namespace",		Opt_mds_namespace),
189 	fsparam_flag_no ("poolperm",			Opt_poolperm),
190 	fsparam_flag_no ("quotadf",			Opt_quotadf),
191 	fsparam_u32	("rasize",			Opt_rasize),
192 	fsparam_flag_no ("rbytes",			Opt_rbytes),
193 	fsparam_u32	("readdir_max_bytes",		Opt_readdir_max_bytes),
194 	fsparam_u32	("readdir_max_entries",		Opt_readdir_max_entries),
195 	fsparam_enum	("recover_session",		Opt_recover_session, ceph_param_recover),
196 	fsparam_flag_no ("require_active_mds",		Opt_require_active_mds),
197 	fsparam_u32	("rsize",			Opt_rsize),
198 	fsparam_string	("snapdirname",			Opt_snapdirname),
199 	fsparam_string	("source",			Opt_source),
200 	fsparam_u32	("wsize",			Opt_wsize),
201 	fsparam_flag_no	("wsync",			Opt_wsync),
202 	{}
203 };
204 
205 struct ceph_parse_opts_ctx {
206 	struct ceph_options		*copts;
207 	struct ceph_mount_options	*opts;
208 };
209 
210 /*
211  * Remove adjacent slashes and then the trailing slash, unless it is
212  * the only remaining character.
213  *
214  * E.g. "//dir1////dir2///" --> "/dir1/dir2", "///" --> "/".
215  */
216 static void canonicalize_path(char *path)
217 {
218 	int i, j = 0;
219 
220 	for (i = 0; path[i] != '\0'; i++) {
221 		if (path[i] != '/' || j < 1 || path[j - 1] != '/')
222 			path[j++] = path[i];
223 	}
224 
225 	if (j > 1 && path[j - 1] == '/')
226 		j--;
227 	path[j] = '\0';
228 }
229 
230 /*
231  * Parse the source parameter.  Distinguish the server list from the path.
232  *
233  * The source will look like:
234  *     <server_spec>[,<server_spec>...]:[<path>]
235  * where
236  *     <server_spec> is <ip>[:<port>]
237  *     <path> is optional, but if present must begin with '/'
238  */
239 static int ceph_parse_source(struct fs_parameter *param, struct fs_context *fc)
240 {
241 	struct ceph_parse_opts_ctx *pctx = fc->fs_private;
242 	struct ceph_mount_options *fsopt = pctx->opts;
243 	char *dev_name = param->string, *dev_name_end;
244 	int ret;
245 
246 	dout("%s '%s'\n", __func__, dev_name);
247 	if (!dev_name || !*dev_name)
248 		return invalfc(fc, "Empty source");
249 
250 	dev_name_end = strchr(dev_name, '/');
251 	if (dev_name_end) {
252 		/*
253 		 * The server_path will include the whole chars from userland
254 		 * including the leading '/'.
255 		 */
256 		kfree(fsopt->server_path);
257 		fsopt->server_path = kstrdup(dev_name_end, GFP_KERNEL);
258 		if (!fsopt->server_path)
259 			return -ENOMEM;
260 
261 		canonicalize_path(fsopt->server_path);
262 	} else {
263 		dev_name_end = dev_name + strlen(dev_name);
264 	}
265 
266 	dev_name_end--;		/* back up to ':' separator */
267 	if (dev_name_end < dev_name || *dev_name_end != ':')
268 		return invalfc(fc, "No path or : separator in source");
269 
270 	dout("device name '%.*s'\n", (int)(dev_name_end - dev_name), dev_name);
271 	if (fsopt->server_path)
272 		dout("server path '%s'\n", fsopt->server_path);
273 
274 	ret = ceph_parse_mon_ips(param->string, dev_name_end - dev_name,
275 				 pctx->copts, fc->log.log);
276 	if (ret)
277 		return ret;
278 
279 	fc->source = param->string;
280 	param->string = NULL;
281 	return 0;
282 }
283 
284 static int ceph_parse_mount_param(struct fs_context *fc,
285 				  struct fs_parameter *param)
286 {
287 	struct ceph_parse_opts_ctx *pctx = fc->fs_private;
288 	struct ceph_mount_options *fsopt = pctx->opts;
289 	struct fs_parse_result result;
290 	unsigned int mode;
291 	int token, ret;
292 
293 	ret = ceph_parse_param(param, pctx->copts, fc->log.log);
294 	if (ret != -ENOPARAM)
295 		return ret;
296 
297 	token = fs_parse(fc, ceph_mount_parameters, param, &result);
298 	dout("%s fs_parse '%s' token %d\n", __func__, param->key, token);
299 	if (token < 0)
300 		return token;
301 
302 	switch (token) {
303 	case Opt_snapdirname:
304 		kfree(fsopt->snapdir_name);
305 		fsopt->snapdir_name = param->string;
306 		param->string = NULL;
307 		break;
308 	case Opt_mds_namespace:
309 		kfree(fsopt->mds_namespace);
310 		fsopt->mds_namespace = param->string;
311 		param->string = NULL;
312 		break;
313 	case Opt_recover_session:
314 		mode = result.uint_32;
315 		if (mode == ceph_recover_session_no)
316 			fsopt->flags &= ~CEPH_MOUNT_OPT_CLEANRECOVER;
317 		else if (mode == ceph_recover_session_clean)
318 			fsopt->flags |= CEPH_MOUNT_OPT_CLEANRECOVER;
319 		else
320 			BUG();
321 		break;
322 	case Opt_source:
323 		if (fc->source)
324 			return invalfc(fc, "Multiple sources specified");
325 		return ceph_parse_source(param, fc);
326 	case Opt_wsize:
327 		if (result.uint_32 < PAGE_SIZE ||
328 		    result.uint_32 > CEPH_MAX_WRITE_SIZE)
329 			goto out_of_range;
330 		fsopt->wsize = ALIGN(result.uint_32, PAGE_SIZE);
331 		break;
332 	case Opt_rsize:
333 		if (result.uint_32 < PAGE_SIZE ||
334 		    result.uint_32 > CEPH_MAX_READ_SIZE)
335 			goto out_of_range;
336 		fsopt->rsize = ALIGN(result.uint_32, PAGE_SIZE);
337 		break;
338 	case Opt_rasize:
339 		fsopt->rasize = ALIGN(result.uint_32, PAGE_SIZE);
340 		break;
341 	case Opt_caps_wanted_delay_min:
342 		if (result.uint_32 < 1)
343 			goto out_of_range;
344 		fsopt->caps_wanted_delay_min = result.uint_32;
345 		break;
346 	case Opt_caps_wanted_delay_max:
347 		if (result.uint_32 < 1)
348 			goto out_of_range;
349 		fsopt->caps_wanted_delay_max = result.uint_32;
350 		break;
351 	case Opt_caps_max:
352 		if (result.int_32 < 0)
353 			goto out_of_range;
354 		fsopt->caps_max = result.int_32;
355 		break;
356 	case Opt_readdir_max_entries:
357 		if (result.uint_32 < 1)
358 			goto out_of_range;
359 		fsopt->max_readdir = result.uint_32;
360 		break;
361 	case Opt_readdir_max_bytes:
362 		if (result.uint_32 < PAGE_SIZE && result.uint_32 != 0)
363 			goto out_of_range;
364 		fsopt->max_readdir_bytes = result.uint_32;
365 		break;
366 	case Opt_congestion_kb:
367 		if (result.uint_32 < 1024) /* at least 1M */
368 			goto out_of_range;
369 		fsopt->congestion_kb = result.uint_32;
370 		break;
371 	case Opt_dirstat:
372 		if (!result.negated)
373 			fsopt->flags |= CEPH_MOUNT_OPT_DIRSTAT;
374 		else
375 			fsopt->flags &= ~CEPH_MOUNT_OPT_DIRSTAT;
376 		break;
377 	case Opt_rbytes:
378 		if (!result.negated)
379 			fsopt->flags |= CEPH_MOUNT_OPT_RBYTES;
380 		else
381 			fsopt->flags &= ~CEPH_MOUNT_OPT_RBYTES;
382 		break;
383 	case Opt_asyncreaddir:
384 		if (!result.negated)
385 			fsopt->flags &= ~CEPH_MOUNT_OPT_NOASYNCREADDIR;
386 		else
387 			fsopt->flags |= CEPH_MOUNT_OPT_NOASYNCREADDIR;
388 		break;
389 	case Opt_dcache:
390 		if (!result.negated)
391 			fsopt->flags |= CEPH_MOUNT_OPT_DCACHE;
392 		else
393 			fsopt->flags &= ~CEPH_MOUNT_OPT_DCACHE;
394 		break;
395 	case Opt_ino32:
396 		if (!result.negated)
397 			fsopt->flags |= CEPH_MOUNT_OPT_INO32;
398 		else
399 			fsopt->flags &= ~CEPH_MOUNT_OPT_INO32;
400 		break;
401 
402 	case Opt_fscache:
403 #ifdef CONFIG_CEPH_FSCACHE
404 		kfree(fsopt->fscache_uniq);
405 		fsopt->fscache_uniq = NULL;
406 		if (result.negated) {
407 			fsopt->flags &= ~CEPH_MOUNT_OPT_FSCACHE;
408 		} else {
409 			fsopt->flags |= CEPH_MOUNT_OPT_FSCACHE;
410 			fsopt->fscache_uniq = param->string;
411 			param->string = NULL;
412 		}
413 		break;
414 #else
415 		return invalfc(fc, "fscache support is disabled");
416 #endif
417 	case Opt_poolperm:
418 		if (!result.negated)
419 			fsopt->flags &= ~CEPH_MOUNT_OPT_NOPOOLPERM;
420 		else
421 			fsopt->flags |= CEPH_MOUNT_OPT_NOPOOLPERM;
422 		break;
423 	case Opt_require_active_mds:
424 		if (!result.negated)
425 			fsopt->flags &= ~CEPH_MOUNT_OPT_MOUNTWAIT;
426 		else
427 			fsopt->flags |= CEPH_MOUNT_OPT_MOUNTWAIT;
428 		break;
429 	case Opt_quotadf:
430 		if (!result.negated)
431 			fsopt->flags &= ~CEPH_MOUNT_OPT_NOQUOTADF;
432 		else
433 			fsopt->flags |= CEPH_MOUNT_OPT_NOQUOTADF;
434 		break;
435 	case Opt_copyfrom:
436 		if (!result.negated)
437 			fsopt->flags &= ~CEPH_MOUNT_OPT_NOCOPYFROM;
438 		else
439 			fsopt->flags |= CEPH_MOUNT_OPT_NOCOPYFROM;
440 		break;
441 	case Opt_acl:
442 		if (!result.negated) {
443 #ifdef CONFIG_CEPH_FS_POSIX_ACL
444 			fc->sb_flags |= SB_POSIXACL;
445 #else
446 			return invalfc(fc, "POSIX ACL support is disabled");
447 #endif
448 		} else {
449 			fc->sb_flags &= ~SB_POSIXACL;
450 		}
451 		break;
452 	case Opt_wsync:
453 		if (!result.negated)
454 			fsopt->flags &= ~CEPH_MOUNT_OPT_ASYNC_DIROPS;
455 		else
456 			fsopt->flags |= CEPH_MOUNT_OPT_ASYNC_DIROPS;
457 		break;
458 	default:
459 		BUG();
460 	}
461 	return 0;
462 
463 out_of_range:
464 	return invalfc(fc, "%s out of range", param->key);
465 }
466 
467 static void destroy_mount_options(struct ceph_mount_options *args)
468 {
469 	dout("destroy_mount_options %p\n", args);
470 	if (!args)
471 		return;
472 
473 	kfree(args->snapdir_name);
474 	kfree(args->mds_namespace);
475 	kfree(args->server_path);
476 	kfree(args->fscache_uniq);
477 	kfree(args);
478 }
479 
480 static int strcmp_null(const char *s1, const char *s2)
481 {
482 	if (!s1 && !s2)
483 		return 0;
484 	if (s1 && !s2)
485 		return -1;
486 	if (!s1 && s2)
487 		return 1;
488 	return strcmp(s1, s2);
489 }
490 
491 static int compare_mount_options(struct ceph_mount_options *new_fsopt,
492 				 struct ceph_options *new_opt,
493 				 struct ceph_fs_client *fsc)
494 {
495 	struct ceph_mount_options *fsopt1 = new_fsopt;
496 	struct ceph_mount_options *fsopt2 = fsc->mount_options;
497 	int ofs = offsetof(struct ceph_mount_options, snapdir_name);
498 	int ret;
499 
500 	ret = memcmp(fsopt1, fsopt2, ofs);
501 	if (ret)
502 		return ret;
503 
504 	ret = strcmp_null(fsopt1->snapdir_name, fsopt2->snapdir_name);
505 	if (ret)
506 		return ret;
507 
508 	ret = strcmp_null(fsopt1->mds_namespace, fsopt2->mds_namespace);
509 	if (ret)
510 		return ret;
511 
512 	ret = strcmp_null(fsopt1->server_path, fsopt2->server_path);
513 	if (ret)
514 		return ret;
515 
516 	ret = strcmp_null(fsopt1->fscache_uniq, fsopt2->fscache_uniq);
517 	if (ret)
518 		return ret;
519 
520 	return ceph_compare_options(new_opt, fsc->client);
521 }
522 
523 /**
524  * ceph_show_options - Show mount options in /proc/mounts
525  * @m: seq_file to write to
526  * @root: root of that (sub)tree
527  */
528 static int ceph_show_options(struct seq_file *m, struct dentry *root)
529 {
530 	struct ceph_fs_client *fsc = ceph_sb_to_client(root->d_sb);
531 	struct ceph_mount_options *fsopt = fsc->mount_options;
532 	size_t pos;
533 	int ret;
534 
535 	/* a comma between MNT/MS and client options */
536 	seq_putc(m, ',');
537 	pos = m->count;
538 
539 	ret = ceph_print_client_options(m, fsc->client, false);
540 	if (ret)
541 		return ret;
542 
543 	/* retract our comma if no client options */
544 	if (m->count == pos)
545 		m->count--;
546 
547 	if (fsopt->flags & CEPH_MOUNT_OPT_DIRSTAT)
548 		seq_puts(m, ",dirstat");
549 	if ((fsopt->flags & CEPH_MOUNT_OPT_RBYTES))
550 		seq_puts(m, ",rbytes");
551 	if (fsopt->flags & CEPH_MOUNT_OPT_NOASYNCREADDIR)
552 		seq_puts(m, ",noasyncreaddir");
553 	if ((fsopt->flags & CEPH_MOUNT_OPT_DCACHE) == 0)
554 		seq_puts(m, ",nodcache");
555 	if (fsopt->flags & CEPH_MOUNT_OPT_INO32)
556 		seq_puts(m, ",ino32");
557 	if (fsopt->flags & CEPH_MOUNT_OPT_FSCACHE) {
558 		seq_show_option(m, "fsc", fsopt->fscache_uniq);
559 	}
560 	if (fsopt->flags & CEPH_MOUNT_OPT_NOPOOLPERM)
561 		seq_puts(m, ",nopoolperm");
562 	if (fsopt->flags & CEPH_MOUNT_OPT_NOQUOTADF)
563 		seq_puts(m, ",noquotadf");
564 
565 #ifdef CONFIG_CEPH_FS_POSIX_ACL
566 	if (root->d_sb->s_flags & SB_POSIXACL)
567 		seq_puts(m, ",acl");
568 	else
569 		seq_puts(m, ",noacl");
570 #endif
571 
572 	if ((fsopt->flags & CEPH_MOUNT_OPT_NOCOPYFROM) == 0)
573 		seq_puts(m, ",copyfrom");
574 
575 	if (fsopt->mds_namespace)
576 		seq_show_option(m, "mds_namespace", fsopt->mds_namespace);
577 
578 	if (fsopt->flags & CEPH_MOUNT_OPT_CLEANRECOVER)
579 		seq_show_option(m, "recover_session", "clean");
580 
581 	if (!(fsopt->flags & CEPH_MOUNT_OPT_ASYNC_DIROPS))
582 		seq_puts(m, ",wsync");
583 
584 	if (fsopt->wsize != CEPH_MAX_WRITE_SIZE)
585 		seq_printf(m, ",wsize=%u", fsopt->wsize);
586 	if (fsopt->rsize != CEPH_MAX_READ_SIZE)
587 		seq_printf(m, ",rsize=%u", fsopt->rsize);
588 	if (fsopt->rasize != CEPH_RASIZE_DEFAULT)
589 		seq_printf(m, ",rasize=%u", fsopt->rasize);
590 	if (fsopt->congestion_kb != default_congestion_kb())
591 		seq_printf(m, ",write_congestion_kb=%u", fsopt->congestion_kb);
592 	if (fsopt->caps_max)
593 		seq_printf(m, ",caps_max=%d", fsopt->caps_max);
594 	if (fsopt->caps_wanted_delay_min != CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT)
595 		seq_printf(m, ",caps_wanted_delay_min=%u",
596 			 fsopt->caps_wanted_delay_min);
597 	if (fsopt->caps_wanted_delay_max != CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT)
598 		seq_printf(m, ",caps_wanted_delay_max=%u",
599 			   fsopt->caps_wanted_delay_max);
600 	if (fsopt->max_readdir != CEPH_MAX_READDIR_DEFAULT)
601 		seq_printf(m, ",readdir_max_entries=%u", fsopt->max_readdir);
602 	if (fsopt->max_readdir_bytes != CEPH_MAX_READDIR_BYTES_DEFAULT)
603 		seq_printf(m, ",readdir_max_bytes=%u", fsopt->max_readdir_bytes);
604 	if (strcmp(fsopt->snapdir_name, CEPH_SNAPDIRNAME_DEFAULT))
605 		seq_show_option(m, "snapdirname", fsopt->snapdir_name);
606 
607 	return 0;
608 }
609 
610 /*
611  * handle any mon messages the standard library doesn't understand.
612  * return error if we don't either.
613  */
614 static int extra_mon_dispatch(struct ceph_client *client, struct ceph_msg *msg)
615 {
616 	struct ceph_fs_client *fsc = client->private;
617 	int type = le16_to_cpu(msg->hdr.type);
618 
619 	switch (type) {
620 	case CEPH_MSG_MDS_MAP:
621 		ceph_mdsc_handle_mdsmap(fsc->mdsc, msg);
622 		return 0;
623 	case CEPH_MSG_FS_MAP_USER:
624 		ceph_mdsc_handle_fsmap(fsc->mdsc, msg);
625 		return 0;
626 	default:
627 		return -1;
628 	}
629 }
630 
631 /*
632  * create a new fs client
633  *
634  * Success or not, this function consumes @fsopt and @opt.
635  */
636 static struct ceph_fs_client *create_fs_client(struct ceph_mount_options *fsopt,
637 					struct ceph_options *opt)
638 {
639 	struct ceph_fs_client *fsc;
640 	int err;
641 
642 	fsc = kzalloc(sizeof(*fsc), GFP_KERNEL);
643 	if (!fsc) {
644 		err = -ENOMEM;
645 		goto fail;
646 	}
647 
648 	fsc->client = ceph_create_client(opt, fsc);
649 	if (IS_ERR(fsc->client)) {
650 		err = PTR_ERR(fsc->client);
651 		goto fail;
652 	}
653 	opt = NULL; /* fsc->client now owns this */
654 
655 	fsc->client->extra_mon_dispatch = extra_mon_dispatch;
656 	ceph_set_opt(fsc->client, ABORT_ON_FULL);
657 
658 	if (!fsopt->mds_namespace) {
659 		ceph_monc_want_map(&fsc->client->monc, CEPH_SUB_MDSMAP,
660 				   0, true);
661 	} else {
662 		ceph_monc_want_map(&fsc->client->monc, CEPH_SUB_FSMAP,
663 				   0, false);
664 	}
665 
666 	fsc->mount_options = fsopt;
667 
668 	fsc->sb = NULL;
669 	fsc->mount_state = CEPH_MOUNT_MOUNTING;
670 	fsc->filp_gen = 1;
671 	fsc->have_copy_from2 = true;
672 
673 	atomic_long_set(&fsc->writeback_count, 0);
674 
675 	err = -ENOMEM;
676 	/*
677 	 * The number of concurrent works can be high but they don't need
678 	 * to be processed in parallel, limit concurrency.
679 	 */
680 	fsc->inode_wq = alloc_workqueue("ceph-inode", WQ_UNBOUND, 0);
681 	if (!fsc->inode_wq)
682 		goto fail_client;
683 	fsc->cap_wq = alloc_workqueue("ceph-cap", 0, 1);
684 	if (!fsc->cap_wq)
685 		goto fail_inode_wq;
686 
687 	spin_lock(&ceph_fsc_lock);
688 	list_add_tail(&fsc->metric_wakeup, &ceph_fsc_list);
689 	spin_unlock(&ceph_fsc_lock);
690 
691 	return fsc;
692 
693 fail_inode_wq:
694 	destroy_workqueue(fsc->inode_wq);
695 fail_client:
696 	ceph_destroy_client(fsc->client);
697 fail:
698 	kfree(fsc);
699 	if (opt)
700 		ceph_destroy_options(opt);
701 	destroy_mount_options(fsopt);
702 	return ERR_PTR(err);
703 }
704 
705 static void flush_fs_workqueues(struct ceph_fs_client *fsc)
706 {
707 	flush_workqueue(fsc->inode_wq);
708 	flush_workqueue(fsc->cap_wq);
709 }
710 
711 static void destroy_fs_client(struct ceph_fs_client *fsc)
712 {
713 	dout("destroy_fs_client %p\n", fsc);
714 
715 	spin_lock(&ceph_fsc_lock);
716 	list_del(&fsc->metric_wakeup);
717 	spin_unlock(&ceph_fsc_lock);
718 
719 	ceph_mdsc_destroy(fsc);
720 	destroy_workqueue(fsc->inode_wq);
721 	destroy_workqueue(fsc->cap_wq);
722 
723 	destroy_mount_options(fsc->mount_options);
724 
725 	ceph_destroy_client(fsc->client);
726 
727 	kfree(fsc);
728 	dout("destroy_fs_client %p done\n", fsc);
729 }
730 
731 /*
732  * caches
733  */
734 struct kmem_cache *ceph_inode_cachep;
735 struct kmem_cache *ceph_cap_cachep;
736 struct kmem_cache *ceph_cap_flush_cachep;
737 struct kmem_cache *ceph_dentry_cachep;
738 struct kmem_cache *ceph_file_cachep;
739 struct kmem_cache *ceph_dir_file_cachep;
740 struct kmem_cache *ceph_mds_request_cachep;
741 mempool_t *ceph_wb_pagevec_pool;
742 
743 static void ceph_inode_init_once(void *foo)
744 {
745 	struct ceph_inode_info *ci = foo;
746 	inode_init_once(&ci->vfs_inode);
747 }
748 
749 static int __init init_caches(void)
750 {
751 	int error = -ENOMEM;
752 
753 	ceph_inode_cachep = kmem_cache_create("ceph_inode_info",
754 				      sizeof(struct ceph_inode_info),
755 				      __alignof__(struct ceph_inode_info),
756 				      SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
757 				      SLAB_ACCOUNT, ceph_inode_init_once);
758 	if (!ceph_inode_cachep)
759 		return -ENOMEM;
760 
761 	ceph_cap_cachep = KMEM_CACHE(ceph_cap, SLAB_MEM_SPREAD);
762 	if (!ceph_cap_cachep)
763 		goto bad_cap;
764 	ceph_cap_flush_cachep = KMEM_CACHE(ceph_cap_flush,
765 					   SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
766 	if (!ceph_cap_flush_cachep)
767 		goto bad_cap_flush;
768 
769 	ceph_dentry_cachep = KMEM_CACHE(ceph_dentry_info,
770 					SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
771 	if (!ceph_dentry_cachep)
772 		goto bad_dentry;
773 
774 	ceph_file_cachep = KMEM_CACHE(ceph_file_info, SLAB_MEM_SPREAD);
775 	if (!ceph_file_cachep)
776 		goto bad_file;
777 
778 	ceph_dir_file_cachep = KMEM_CACHE(ceph_dir_file_info, SLAB_MEM_SPREAD);
779 	if (!ceph_dir_file_cachep)
780 		goto bad_dir_file;
781 
782 	ceph_mds_request_cachep = KMEM_CACHE(ceph_mds_request, SLAB_MEM_SPREAD);
783 	if (!ceph_mds_request_cachep)
784 		goto bad_mds_req;
785 
786 	ceph_wb_pagevec_pool = mempool_create_kmalloc_pool(10, CEPH_MAX_WRITE_SIZE >> PAGE_SHIFT);
787 	if (!ceph_wb_pagevec_pool)
788 		goto bad_pagevec_pool;
789 
790 	error = ceph_fscache_register();
791 	if (error)
792 		goto bad_fscache;
793 
794 	return 0;
795 
796 bad_fscache:
797 	kmem_cache_destroy(ceph_mds_request_cachep);
798 bad_pagevec_pool:
799 	mempool_destroy(ceph_wb_pagevec_pool);
800 bad_mds_req:
801 	kmem_cache_destroy(ceph_dir_file_cachep);
802 bad_dir_file:
803 	kmem_cache_destroy(ceph_file_cachep);
804 bad_file:
805 	kmem_cache_destroy(ceph_dentry_cachep);
806 bad_dentry:
807 	kmem_cache_destroy(ceph_cap_flush_cachep);
808 bad_cap_flush:
809 	kmem_cache_destroy(ceph_cap_cachep);
810 bad_cap:
811 	kmem_cache_destroy(ceph_inode_cachep);
812 	return error;
813 }
814 
815 static void destroy_caches(void)
816 {
817 	/*
818 	 * Make sure all delayed rcu free inodes are flushed before we
819 	 * destroy cache.
820 	 */
821 	rcu_barrier();
822 
823 	kmem_cache_destroy(ceph_inode_cachep);
824 	kmem_cache_destroy(ceph_cap_cachep);
825 	kmem_cache_destroy(ceph_cap_flush_cachep);
826 	kmem_cache_destroy(ceph_dentry_cachep);
827 	kmem_cache_destroy(ceph_file_cachep);
828 	kmem_cache_destroy(ceph_dir_file_cachep);
829 	kmem_cache_destroy(ceph_mds_request_cachep);
830 	mempool_destroy(ceph_wb_pagevec_pool);
831 
832 	ceph_fscache_unregister();
833 }
834 
835 static void __ceph_umount_begin(struct ceph_fs_client *fsc)
836 {
837 	ceph_osdc_abort_requests(&fsc->client->osdc, -EIO);
838 	ceph_mdsc_force_umount(fsc->mdsc);
839 	fsc->filp_gen++; // invalidate open files
840 }
841 
842 /*
843  * ceph_umount_begin - initiate forced umount.  Tear down the
844  * mount, skipping steps that may hang while waiting for server(s).
845  */
846 void ceph_umount_begin(struct super_block *sb)
847 {
848 	struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
849 
850 	dout("ceph_umount_begin - starting forced umount\n");
851 	if (!fsc)
852 		return;
853 	fsc->mount_state = CEPH_MOUNT_SHUTDOWN;
854 	__ceph_umount_begin(fsc);
855 }
856 
857 static const struct super_operations ceph_super_ops = {
858 	.alloc_inode	= ceph_alloc_inode,
859 	.free_inode	= ceph_free_inode,
860 	.write_inode    = ceph_write_inode,
861 	.drop_inode	= generic_delete_inode,
862 	.evict_inode	= ceph_evict_inode,
863 	.sync_fs        = ceph_sync_fs,
864 	.put_super	= ceph_put_super,
865 	.show_options   = ceph_show_options,
866 	.statfs		= ceph_statfs,
867 	.umount_begin   = ceph_umount_begin,
868 };
869 
870 /*
871  * Bootstrap mount by opening the root directory.  Note the mount
872  * @started time from caller, and time out if this takes too long.
873  */
874 static struct dentry *open_root_dentry(struct ceph_fs_client *fsc,
875 				       const char *path,
876 				       unsigned long started)
877 {
878 	struct ceph_mds_client *mdsc = fsc->mdsc;
879 	struct ceph_mds_request *req = NULL;
880 	int err;
881 	struct dentry *root;
882 
883 	/* open dir */
884 	dout("open_root_inode opening '%s'\n", path);
885 	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_GETATTR, USE_ANY_MDS);
886 	if (IS_ERR(req))
887 		return ERR_CAST(req);
888 	req->r_path1 = kstrdup(path, GFP_NOFS);
889 	if (!req->r_path1) {
890 		root = ERR_PTR(-ENOMEM);
891 		goto out;
892 	}
893 
894 	req->r_ino1.ino = CEPH_INO_ROOT;
895 	req->r_ino1.snap = CEPH_NOSNAP;
896 	req->r_started = started;
897 	req->r_timeout = fsc->client->options->mount_timeout;
898 	req->r_args.getattr.mask = cpu_to_le32(CEPH_STAT_CAP_INODE);
899 	req->r_num_caps = 2;
900 	err = ceph_mdsc_do_request(mdsc, NULL, req);
901 	if (err == 0) {
902 		struct inode *inode = req->r_target_inode;
903 		req->r_target_inode = NULL;
904 		dout("open_root_inode success\n");
905 		root = d_make_root(inode);
906 		if (!root) {
907 			root = ERR_PTR(-ENOMEM);
908 			goto out;
909 		}
910 		dout("open_root_inode success, root dentry is %p\n", root);
911 	} else {
912 		root = ERR_PTR(err);
913 	}
914 out:
915 	ceph_mdsc_put_request(req);
916 	return root;
917 }
918 
919 /*
920  * mount: join the ceph cluster, and open root directory.
921  */
922 static struct dentry *ceph_real_mount(struct ceph_fs_client *fsc,
923 				      struct fs_context *fc)
924 {
925 	int err;
926 	unsigned long started = jiffies;  /* note the start time */
927 	struct dentry *root;
928 
929 	dout("mount start %p\n", fsc);
930 	mutex_lock(&fsc->client->mount_mutex);
931 
932 	if (!fsc->sb->s_root) {
933 		const char *path = fsc->mount_options->server_path ?
934 				     fsc->mount_options->server_path + 1 : "";
935 
936 		err = __ceph_open_session(fsc->client, started);
937 		if (err < 0)
938 			goto out;
939 
940 		/* setup fscache */
941 		if (fsc->mount_options->flags & CEPH_MOUNT_OPT_FSCACHE) {
942 			err = ceph_fscache_register_fs(fsc, fc);
943 			if (err < 0)
944 				goto out;
945 		}
946 
947 		dout("mount opening path '%s'\n", path);
948 
949 		ceph_fs_debugfs_init(fsc);
950 
951 		root = open_root_dentry(fsc, path, started);
952 		if (IS_ERR(root)) {
953 			err = PTR_ERR(root);
954 			goto out;
955 		}
956 		fsc->sb->s_root = dget(root);
957 	} else {
958 		root = dget(fsc->sb->s_root);
959 	}
960 
961 	fsc->mount_state = CEPH_MOUNT_MOUNTED;
962 	dout("mount success\n");
963 	mutex_unlock(&fsc->client->mount_mutex);
964 	return root;
965 
966 out:
967 	mutex_unlock(&fsc->client->mount_mutex);
968 	return ERR_PTR(err);
969 }
970 
971 static int ceph_set_super(struct super_block *s, struct fs_context *fc)
972 {
973 	struct ceph_fs_client *fsc = s->s_fs_info;
974 	int ret;
975 
976 	dout("set_super %p\n", s);
977 
978 	s->s_maxbytes = MAX_LFS_FILESIZE;
979 
980 	s->s_xattr = ceph_xattr_handlers;
981 	fsc->sb = s;
982 	fsc->max_file_size = 1ULL << 40; /* temp value until we get mdsmap */
983 
984 	s->s_op = &ceph_super_ops;
985 	s->s_d_op = &ceph_dentry_ops;
986 	s->s_export_op = &ceph_export_ops;
987 
988 	s->s_time_gran = 1;
989 	s->s_time_min = 0;
990 	s->s_time_max = U32_MAX;
991 
992 	ret = set_anon_super_fc(s, fc);
993 	if (ret != 0)
994 		fsc->sb = NULL;
995 	return ret;
996 }
997 
998 /*
999  * share superblock if same fs AND options
1000  */
1001 static int ceph_compare_super(struct super_block *sb, struct fs_context *fc)
1002 {
1003 	struct ceph_fs_client *new = fc->s_fs_info;
1004 	struct ceph_mount_options *fsopt = new->mount_options;
1005 	struct ceph_options *opt = new->client->options;
1006 	struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
1007 
1008 	dout("ceph_compare_super %p\n", sb);
1009 
1010 	if (compare_mount_options(fsopt, opt, fsc)) {
1011 		dout("monitor(s)/mount options don't match\n");
1012 		return 0;
1013 	}
1014 	if ((opt->flags & CEPH_OPT_FSID) &&
1015 	    ceph_fsid_compare(&opt->fsid, &fsc->client->fsid)) {
1016 		dout("fsid doesn't match\n");
1017 		return 0;
1018 	}
1019 	if (fc->sb_flags != (sb->s_flags & ~SB_BORN)) {
1020 		dout("flags differ\n");
1021 		return 0;
1022 	}
1023 
1024 	if (fsc->blocklisted && !ceph_test_mount_opt(fsc, CLEANRECOVER)) {
1025 		dout("client is blocklisted (and CLEANRECOVER is not set)\n");
1026 		return 0;
1027 	}
1028 
1029 	if (fsc->mount_state == CEPH_MOUNT_SHUTDOWN) {
1030 		dout("client has been forcibly unmounted\n");
1031 		return 0;
1032 	}
1033 
1034 	return 1;
1035 }
1036 
1037 /*
1038  * construct our own bdi so we can control readahead, etc.
1039  */
1040 static atomic_long_t bdi_seq = ATOMIC_LONG_INIT(0);
1041 
1042 static int ceph_setup_bdi(struct super_block *sb, struct ceph_fs_client *fsc)
1043 {
1044 	int err;
1045 
1046 	err = super_setup_bdi_name(sb, "ceph-%ld",
1047 				   atomic_long_inc_return(&bdi_seq));
1048 	if (err)
1049 		return err;
1050 
1051 	/* set ra_pages based on rasize mount option? */
1052 	sb->s_bdi->ra_pages = fsc->mount_options->rasize >> PAGE_SHIFT;
1053 
1054 	/* set io_pages based on max osd read size */
1055 	sb->s_bdi->io_pages = fsc->mount_options->rsize >> PAGE_SHIFT;
1056 
1057 	return 0;
1058 }
1059 
1060 static int ceph_get_tree(struct fs_context *fc)
1061 {
1062 	struct ceph_parse_opts_ctx *pctx = fc->fs_private;
1063 	struct super_block *sb;
1064 	struct ceph_fs_client *fsc;
1065 	struct dentry *res;
1066 	int (*compare_super)(struct super_block *, struct fs_context *) =
1067 		ceph_compare_super;
1068 	int err;
1069 
1070 	dout("ceph_get_tree\n");
1071 
1072 	if (!fc->source)
1073 		return invalfc(fc, "No source");
1074 
1075 	/* create client (which we may/may not use) */
1076 	fsc = create_fs_client(pctx->opts, pctx->copts);
1077 	pctx->opts = NULL;
1078 	pctx->copts = NULL;
1079 	if (IS_ERR(fsc)) {
1080 		err = PTR_ERR(fsc);
1081 		goto out_final;
1082 	}
1083 
1084 	err = ceph_mdsc_init(fsc);
1085 	if (err < 0)
1086 		goto out;
1087 
1088 	if (ceph_test_opt(fsc->client, NOSHARE))
1089 		compare_super = NULL;
1090 
1091 	fc->s_fs_info = fsc;
1092 	sb = sget_fc(fc, compare_super, ceph_set_super);
1093 	fc->s_fs_info = NULL;
1094 	if (IS_ERR(sb)) {
1095 		err = PTR_ERR(sb);
1096 		goto out;
1097 	}
1098 
1099 	if (ceph_sb_to_client(sb) != fsc) {
1100 		destroy_fs_client(fsc);
1101 		fsc = ceph_sb_to_client(sb);
1102 		dout("get_sb got existing client %p\n", fsc);
1103 	} else {
1104 		dout("get_sb using new client %p\n", fsc);
1105 		err = ceph_setup_bdi(sb, fsc);
1106 		if (err < 0)
1107 			goto out_splat;
1108 	}
1109 
1110 	res = ceph_real_mount(fsc, fc);
1111 	if (IS_ERR(res)) {
1112 		err = PTR_ERR(res);
1113 		goto out_splat;
1114 	}
1115 	dout("root %p inode %p ino %llx.%llx\n", res,
1116 	     d_inode(res), ceph_vinop(d_inode(res)));
1117 	fc->root = fsc->sb->s_root;
1118 	return 0;
1119 
1120 out_splat:
1121 	if (!ceph_mdsmap_is_cluster_available(fsc->mdsc->mdsmap)) {
1122 		pr_info("No mds server is up or the cluster is laggy\n");
1123 		err = -EHOSTUNREACH;
1124 	}
1125 
1126 	ceph_mdsc_close_sessions(fsc->mdsc);
1127 	deactivate_locked_super(sb);
1128 	goto out_final;
1129 
1130 out:
1131 	destroy_fs_client(fsc);
1132 out_final:
1133 	dout("ceph_get_tree fail %d\n", err);
1134 	return err;
1135 }
1136 
1137 static void ceph_free_fc(struct fs_context *fc)
1138 {
1139 	struct ceph_parse_opts_ctx *pctx = fc->fs_private;
1140 
1141 	if (pctx) {
1142 		destroy_mount_options(pctx->opts);
1143 		ceph_destroy_options(pctx->copts);
1144 		kfree(pctx);
1145 	}
1146 }
1147 
1148 static int ceph_reconfigure_fc(struct fs_context *fc)
1149 {
1150 	struct ceph_parse_opts_ctx *pctx = fc->fs_private;
1151 	struct ceph_mount_options *fsopt = pctx->opts;
1152 	struct ceph_fs_client *fsc = ceph_sb_to_client(fc->root->d_sb);
1153 
1154 	if (fsopt->flags & CEPH_MOUNT_OPT_ASYNC_DIROPS)
1155 		ceph_set_mount_opt(fsc, ASYNC_DIROPS);
1156 	else
1157 		ceph_clear_mount_opt(fsc, ASYNC_DIROPS);
1158 
1159 	sync_filesystem(fc->root->d_sb);
1160 	return 0;
1161 }
1162 
1163 static const struct fs_context_operations ceph_context_ops = {
1164 	.free		= ceph_free_fc,
1165 	.parse_param	= ceph_parse_mount_param,
1166 	.get_tree	= ceph_get_tree,
1167 	.reconfigure	= ceph_reconfigure_fc,
1168 };
1169 
1170 /*
1171  * Set up the filesystem mount context.
1172  */
1173 static int ceph_init_fs_context(struct fs_context *fc)
1174 {
1175 	struct ceph_parse_opts_ctx *pctx;
1176 	struct ceph_mount_options *fsopt;
1177 
1178 	pctx = kzalloc(sizeof(*pctx), GFP_KERNEL);
1179 	if (!pctx)
1180 		return -ENOMEM;
1181 
1182 	pctx->copts = ceph_alloc_options();
1183 	if (!pctx->copts)
1184 		goto nomem;
1185 
1186 	pctx->opts = kzalloc(sizeof(*pctx->opts), GFP_KERNEL);
1187 	if (!pctx->opts)
1188 		goto nomem;
1189 
1190 	fsopt = pctx->opts;
1191 	fsopt->flags = CEPH_MOUNT_OPT_DEFAULT;
1192 
1193 	fsopt->wsize = CEPH_MAX_WRITE_SIZE;
1194 	fsopt->rsize = CEPH_MAX_READ_SIZE;
1195 	fsopt->rasize = CEPH_RASIZE_DEFAULT;
1196 	fsopt->snapdir_name = kstrdup(CEPH_SNAPDIRNAME_DEFAULT, GFP_KERNEL);
1197 	if (!fsopt->snapdir_name)
1198 		goto nomem;
1199 
1200 	fsopt->caps_wanted_delay_min = CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT;
1201 	fsopt->caps_wanted_delay_max = CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT;
1202 	fsopt->max_readdir = CEPH_MAX_READDIR_DEFAULT;
1203 	fsopt->max_readdir_bytes = CEPH_MAX_READDIR_BYTES_DEFAULT;
1204 	fsopt->congestion_kb = default_congestion_kb();
1205 
1206 #ifdef CONFIG_CEPH_FS_POSIX_ACL
1207 	fc->sb_flags |= SB_POSIXACL;
1208 #endif
1209 
1210 	fc->fs_private = pctx;
1211 	fc->ops = &ceph_context_ops;
1212 	return 0;
1213 
1214 nomem:
1215 	destroy_mount_options(pctx->opts);
1216 	ceph_destroy_options(pctx->copts);
1217 	kfree(pctx);
1218 	return -ENOMEM;
1219 }
1220 
1221 static void ceph_kill_sb(struct super_block *s)
1222 {
1223 	struct ceph_fs_client *fsc = ceph_sb_to_client(s);
1224 
1225 	dout("kill_sb %p\n", s);
1226 
1227 	ceph_mdsc_pre_umount(fsc->mdsc);
1228 	flush_fs_workqueues(fsc);
1229 
1230 	kill_anon_super(s);
1231 
1232 	fsc->client->extra_mon_dispatch = NULL;
1233 	ceph_fs_debugfs_cleanup(fsc);
1234 
1235 	ceph_fscache_unregister_fs(fsc);
1236 
1237 	destroy_fs_client(fsc);
1238 }
1239 
1240 static struct file_system_type ceph_fs_type = {
1241 	.owner		= THIS_MODULE,
1242 	.name		= "ceph",
1243 	.init_fs_context = ceph_init_fs_context,
1244 	.kill_sb	= ceph_kill_sb,
1245 	.fs_flags	= FS_RENAME_DOES_D_MOVE,
1246 };
1247 MODULE_ALIAS_FS("ceph");
1248 
1249 int ceph_force_reconnect(struct super_block *sb)
1250 {
1251 	struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
1252 	int err = 0;
1253 
1254 	fsc->mount_state = CEPH_MOUNT_RECOVER;
1255 	__ceph_umount_begin(fsc);
1256 
1257 	/* Make sure all page caches get invalidated.
1258 	 * see remove_session_caps_cb() */
1259 	flush_workqueue(fsc->inode_wq);
1260 
1261 	/* In case that we were blocklisted. This also reset
1262 	 * all mon/osd connections */
1263 	ceph_reset_client_addr(fsc->client);
1264 
1265 	ceph_osdc_clear_abort_err(&fsc->client->osdc);
1266 
1267 	fsc->blocklisted = false;
1268 	fsc->mount_state = CEPH_MOUNT_MOUNTED;
1269 
1270 	if (sb->s_root) {
1271 		err = __ceph_do_getattr(d_inode(sb->s_root), NULL,
1272 					CEPH_STAT_CAP_INODE, true);
1273 	}
1274 	return err;
1275 }
1276 
1277 static int __init init_ceph(void)
1278 {
1279 	int ret = init_caches();
1280 	if (ret)
1281 		goto out;
1282 
1283 	ceph_flock_init();
1284 	ret = register_filesystem(&ceph_fs_type);
1285 	if (ret)
1286 		goto out_caches;
1287 
1288 	pr_info("loaded (mds proto %d)\n", CEPH_MDSC_PROTOCOL);
1289 
1290 	return 0;
1291 
1292 out_caches:
1293 	destroy_caches();
1294 out:
1295 	return ret;
1296 }
1297 
1298 static void __exit exit_ceph(void)
1299 {
1300 	dout("exit_ceph\n");
1301 	unregister_filesystem(&ceph_fs_type);
1302 	destroy_caches();
1303 }
1304 
1305 static int param_set_metrics(const char *val, const struct kernel_param *kp)
1306 {
1307 	struct ceph_fs_client *fsc;
1308 	int ret;
1309 
1310 	ret = param_set_bool(val, kp);
1311 	if (ret) {
1312 		pr_err("Failed to parse sending metrics switch value '%s'\n",
1313 		       val);
1314 		return ret;
1315 	} else if (!disable_send_metrics) {
1316 		// wake up all the mds clients
1317 		spin_lock(&ceph_fsc_lock);
1318 		list_for_each_entry(fsc, &ceph_fsc_list, metric_wakeup) {
1319 			metric_schedule_delayed(&fsc->mdsc->metric);
1320 		}
1321 		spin_unlock(&ceph_fsc_lock);
1322 	}
1323 
1324 	return 0;
1325 }
1326 
1327 static const struct kernel_param_ops param_ops_metrics = {
1328 	.set = param_set_metrics,
1329 	.get = param_get_bool,
1330 };
1331 
1332 bool disable_send_metrics = false;
1333 module_param_cb(disable_send_metrics, &param_ops_metrics, &disable_send_metrics, 0644);
1334 MODULE_PARM_DESC(disable_send_metrics, "Enable sending perf metrics to ceph cluster (default: on)");
1335 
1336 module_init(init_ceph);
1337 module_exit(exit_ceph);
1338 
1339 MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
1340 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
1341 MODULE_AUTHOR("Patience Warnick <patience@newdream.net>");
1342 MODULE_DESCRIPTION("Ceph filesystem for Linux");
1343 MODULE_LICENSE("GPL");
1344