xref: /openbmc/linux/fs/ceph/super.c (revision 34fa67e7)
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 	return 0;
791 
792 bad_pagevec_pool:
793 	kmem_cache_destroy(ceph_mds_request_cachep);
794 bad_mds_req:
795 	kmem_cache_destroy(ceph_dir_file_cachep);
796 bad_dir_file:
797 	kmem_cache_destroy(ceph_file_cachep);
798 bad_file:
799 	kmem_cache_destroy(ceph_dentry_cachep);
800 bad_dentry:
801 	kmem_cache_destroy(ceph_cap_flush_cachep);
802 bad_cap_flush:
803 	kmem_cache_destroy(ceph_cap_cachep);
804 bad_cap:
805 	kmem_cache_destroy(ceph_inode_cachep);
806 	return error;
807 }
808 
809 static void destroy_caches(void)
810 {
811 	/*
812 	 * Make sure all delayed rcu free inodes are flushed before we
813 	 * destroy cache.
814 	 */
815 	rcu_barrier();
816 
817 	kmem_cache_destroy(ceph_inode_cachep);
818 	kmem_cache_destroy(ceph_cap_cachep);
819 	kmem_cache_destroy(ceph_cap_flush_cachep);
820 	kmem_cache_destroy(ceph_dentry_cachep);
821 	kmem_cache_destroy(ceph_file_cachep);
822 	kmem_cache_destroy(ceph_dir_file_cachep);
823 	kmem_cache_destroy(ceph_mds_request_cachep);
824 	mempool_destroy(ceph_wb_pagevec_pool);
825 }
826 
827 static void __ceph_umount_begin(struct ceph_fs_client *fsc)
828 {
829 	ceph_osdc_abort_requests(&fsc->client->osdc, -EIO);
830 	ceph_mdsc_force_umount(fsc->mdsc);
831 	fsc->filp_gen++; // invalidate open files
832 }
833 
834 /*
835  * ceph_umount_begin - initiate forced umount.  Tear down the
836  * mount, skipping steps that may hang while waiting for server(s).
837  */
838 void ceph_umount_begin(struct super_block *sb)
839 {
840 	struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
841 
842 	dout("ceph_umount_begin - starting forced umount\n");
843 	if (!fsc)
844 		return;
845 	fsc->mount_state = CEPH_MOUNT_SHUTDOWN;
846 	__ceph_umount_begin(fsc);
847 }
848 
849 static const struct super_operations ceph_super_ops = {
850 	.alloc_inode	= ceph_alloc_inode,
851 	.free_inode	= ceph_free_inode,
852 	.write_inode    = ceph_write_inode,
853 	.drop_inode	= generic_delete_inode,
854 	.evict_inode	= ceph_evict_inode,
855 	.sync_fs        = ceph_sync_fs,
856 	.put_super	= ceph_put_super,
857 	.show_options   = ceph_show_options,
858 	.statfs		= ceph_statfs,
859 	.umount_begin   = ceph_umount_begin,
860 };
861 
862 /*
863  * Bootstrap mount by opening the root directory.  Note the mount
864  * @started time from caller, and time out if this takes too long.
865  */
866 static struct dentry *open_root_dentry(struct ceph_fs_client *fsc,
867 				       const char *path,
868 				       unsigned long started)
869 {
870 	struct ceph_mds_client *mdsc = fsc->mdsc;
871 	struct ceph_mds_request *req = NULL;
872 	int err;
873 	struct dentry *root;
874 
875 	/* open dir */
876 	dout("open_root_inode opening '%s'\n", path);
877 	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_GETATTR, USE_ANY_MDS);
878 	if (IS_ERR(req))
879 		return ERR_CAST(req);
880 	req->r_path1 = kstrdup(path, GFP_NOFS);
881 	if (!req->r_path1) {
882 		root = ERR_PTR(-ENOMEM);
883 		goto out;
884 	}
885 
886 	req->r_ino1.ino = CEPH_INO_ROOT;
887 	req->r_ino1.snap = CEPH_NOSNAP;
888 	req->r_started = started;
889 	req->r_timeout = fsc->client->options->mount_timeout;
890 	req->r_args.getattr.mask = cpu_to_le32(CEPH_STAT_CAP_INODE);
891 	req->r_num_caps = 2;
892 	err = ceph_mdsc_do_request(mdsc, NULL, req);
893 	if (err == 0) {
894 		struct inode *inode = req->r_target_inode;
895 		req->r_target_inode = NULL;
896 		dout("open_root_inode success\n");
897 		root = d_make_root(inode);
898 		if (!root) {
899 			root = ERR_PTR(-ENOMEM);
900 			goto out;
901 		}
902 		dout("open_root_inode success, root dentry is %p\n", root);
903 	} else {
904 		root = ERR_PTR(err);
905 	}
906 out:
907 	ceph_mdsc_put_request(req);
908 	return root;
909 }
910 
911 /*
912  * mount: join the ceph cluster, and open root directory.
913  */
914 static struct dentry *ceph_real_mount(struct ceph_fs_client *fsc,
915 				      struct fs_context *fc)
916 {
917 	int err;
918 	unsigned long started = jiffies;  /* note the start time */
919 	struct dentry *root;
920 
921 	dout("mount start %p\n", fsc);
922 	mutex_lock(&fsc->client->mount_mutex);
923 
924 	if (!fsc->sb->s_root) {
925 		const char *path = fsc->mount_options->server_path ?
926 				     fsc->mount_options->server_path + 1 : "";
927 
928 		err = __ceph_open_session(fsc->client, started);
929 		if (err < 0)
930 			goto out;
931 
932 		/* setup fscache */
933 		if (fsc->mount_options->flags & CEPH_MOUNT_OPT_FSCACHE) {
934 			err = ceph_fscache_register_fs(fsc, fc);
935 			if (err < 0)
936 				goto out;
937 		}
938 
939 		dout("mount opening path '%s'\n", path);
940 
941 		ceph_fs_debugfs_init(fsc);
942 
943 		root = open_root_dentry(fsc, path, started);
944 		if (IS_ERR(root)) {
945 			err = PTR_ERR(root);
946 			goto out;
947 		}
948 		fsc->sb->s_root = dget(root);
949 	} else {
950 		root = dget(fsc->sb->s_root);
951 	}
952 
953 	fsc->mount_state = CEPH_MOUNT_MOUNTED;
954 	dout("mount success\n");
955 	mutex_unlock(&fsc->client->mount_mutex);
956 	return root;
957 
958 out:
959 	mutex_unlock(&fsc->client->mount_mutex);
960 	return ERR_PTR(err);
961 }
962 
963 static int ceph_set_super(struct super_block *s, struct fs_context *fc)
964 {
965 	struct ceph_fs_client *fsc = s->s_fs_info;
966 	int ret;
967 
968 	dout("set_super %p\n", s);
969 
970 	s->s_maxbytes = MAX_LFS_FILESIZE;
971 
972 	s->s_xattr = ceph_xattr_handlers;
973 	fsc->sb = s;
974 	fsc->max_file_size = 1ULL << 40; /* temp value until we get mdsmap */
975 
976 	s->s_op = &ceph_super_ops;
977 	s->s_d_op = &ceph_dentry_ops;
978 	s->s_export_op = &ceph_export_ops;
979 
980 	s->s_time_gran = 1;
981 	s->s_time_min = 0;
982 	s->s_time_max = U32_MAX;
983 
984 	ret = set_anon_super_fc(s, fc);
985 	if (ret != 0)
986 		fsc->sb = NULL;
987 	return ret;
988 }
989 
990 /*
991  * share superblock if same fs AND options
992  */
993 static int ceph_compare_super(struct super_block *sb, struct fs_context *fc)
994 {
995 	struct ceph_fs_client *new = fc->s_fs_info;
996 	struct ceph_mount_options *fsopt = new->mount_options;
997 	struct ceph_options *opt = new->client->options;
998 	struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
999 
1000 	dout("ceph_compare_super %p\n", sb);
1001 
1002 	if (compare_mount_options(fsopt, opt, fsc)) {
1003 		dout("monitor(s)/mount options don't match\n");
1004 		return 0;
1005 	}
1006 	if ((opt->flags & CEPH_OPT_FSID) &&
1007 	    ceph_fsid_compare(&opt->fsid, &fsc->client->fsid)) {
1008 		dout("fsid doesn't match\n");
1009 		return 0;
1010 	}
1011 	if (fc->sb_flags != (sb->s_flags & ~SB_BORN)) {
1012 		dout("flags differ\n");
1013 		return 0;
1014 	}
1015 
1016 	if (fsc->blocklisted && !ceph_test_mount_opt(fsc, CLEANRECOVER)) {
1017 		dout("client is blocklisted (and CLEANRECOVER is not set)\n");
1018 		return 0;
1019 	}
1020 
1021 	if (fsc->mount_state == CEPH_MOUNT_SHUTDOWN) {
1022 		dout("client has been forcibly unmounted\n");
1023 		return 0;
1024 	}
1025 
1026 	return 1;
1027 }
1028 
1029 /*
1030  * construct our own bdi so we can control readahead, etc.
1031  */
1032 static atomic_long_t bdi_seq = ATOMIC_LONG_INIT(0);
1033 
1034 static int ceph_setup_bdi(struct super_block *sb, struct ceph_fs_client *fsc)
1035 {
1036 	int err;
1037 
1038 	err = super_setup_bdi_name(sb, "ceph-%ld",
1039 				   atomic_long_inc_return(&bdi_seq));
1040 	if (err)
1041 		return err;
1042 
1043 	/* set ra_pages based on rasize mount option? */
1044 	sb->s_bdi->ra_pages = fsc->mount_options->rasize >> PAGE_SHIFT;
1045 
1046 	/* set io_pages based on max osd read size */
1047 	sb->s_bdi->io_pages = fsc->mount_options->rsize >> PAGE_SHIFT;
1048 
1049 	return 0;
1050 }
1051 
1052 static int ceph_get_tree(struct fs_context *fc)
1053 {
1054 	struct ceph_parse_opts_ctx *pctx = fc->fs_private;
1055 	struct super_block *sb;
1056 	struct ceph_fs_client *fsc;
1057 	struct dentry *res;
1058 	int (*compare_super)(struct super_block *, struct fs_context *) =
1059 		ceph_compare_super;
1060 	int err;
1061 
1062 	dout("ceph_get_tree\n");
1063 
1064 	if (!fc->source)
1065 		return invalfc(fc, "No source");
1066 
1067 	/* create client (which we may/may not use) */
1068 	fsc = create_fs_client(pctx->opts, pctx->copts);
1069 	pctx->opts = NULL;
1070 	pctx->copts = NULL;
1071 	if (IS_ERR(fsc)) {
1072 		err = PTR_ERR(fsc);
1073 		goto out_final;
1074 	}
1075 
1076 	err = ceph_mdsc_init(fsc);
1077 	if (err < 0)
1078 		goto out;
1079 
1080 	if (ceph_test_opt(fsc->client, NOSHARE))
1081 		compare_super = NULL;
1082 
1083 	fc->s_fs_info = fsc;
1084 	sb = sget_fc(fc, compare_super, ceph_set_super);
1085 	fc->s_fs_info = NULL;
1086 	if (IS_ERR(sb)) {
1087 		err = PTR_ERR(sb);
1088 		goto out;
1089 	}
1090 
1091 	if (ceph_sb_to_client(sb) != fsc) {
1092 		destroy_fs_client(fsc);
1093 		fsc = ceph_sb_to_client(sb);
1094 		dout("get_sb got existing client %p\n", fsc);
1095 	} else {
1096 		dout("get_sb using new client %p\n", fsc);
1097 		err = ceph_setup_bdi(sb, fsc);
1098 		if (err < 0)
1099 			goto out_splat;
1100 	}
1101 
1102 	res = ceph_real_mount(fsc, fc);
1103 	if (IS_ERR(res)) {
1104 		err = PTR_ERR(res);
1105 		goto out_splat;
1106 	}
1107 	dout("root %p inode %p ino %llx.%llx\n", res,
1108 	     d_inode(res), ceph_vinop(d_inode(res)));
1109 	fc->root = fsc->sb->s_root;
1110 	return 0;
1111 
1112 out_splat:
1113 	if (!ceph_mdsmap_is_cluster_available(fsc->mdsc->mdsmap)) {
1114 		pr_info("No mds server is up or the cluster is laggy\n");
1115 		err = -EHOSTUNREACH;
1116 	}
1117 
1118 	ceph_mdsc_close_sessions(fsc->mdsc);
1119 	deactivate_locked_super(sb);
1120 	goto out_final;
1121 
1122 out:
1123 	destroy_fs_client(fsc);
1124 out_final:
1125 	dout("ceph_get_tree fail %d\n", err);
1126 	return err;
1127 }
1128 
1129 static void ceph_free_fc(struct fs_context *fc)
1130 {
1131 	struct ceph_parse_opts_ctx *pctx = fc->fs_private;
1132 
1133 	if (pctx) {
1134 		destroy_mount_options(pctx->opts);
1135 		ceph_destroy_options(pctx->copts);
1136 		kfree(pctx);
1137 	}
1138 }
1139 
1140 static int ceph_reconfigure_fc(struct fs_context *fc)
1141 {
1142 	struct ceph_parse_opts_ctx *pctx = fc->fs_private;
1143 	struct ceph_mount_options *fsopt = pctx->opts;
1144 	struct ceph_fs_client *fsc = ceph_sb_to_client(fc->root->d_sb);
1145 
1146 	if (fsopt->flags & CEPH_MOUNT_OPT_ASYNC_DIROPS)
1147 		ceph_set_mount_opt(fsc, ASYNC_DIROPS);
1148 	else
1149 		ceph_clear_mount_opt(fsc, ASYNC_DIROPS);
1150 
1151 	sync_filesystem(fc->root->d_sb);
1152 	return 0;
1153 }
1154 
1155 static const struct fs_context_operations ceph_context_ops = {
1156 	.free		= ceph_free_fc,
1157 	.parse_param	= ceph_parse_mount_param,
1158 	.get_tree	= ceph_get_tree,
1159 	.reconfigure	= ceph_reconfigure_fc,
1160 };
1161 
1162 /*
1163  * Set up the filesystem mount context.
1164  */
1165 static int ceph_init_fs_context(struct fs_context *fc)
1166 {
1167 	struct ceph_parse_opts_ctx *pctx;
1168 	struct ceph_mount_options *fsopt;
1169 
1170 	pctx = kzalloc(sizeof(*pctx), GFP_KERNEL);
1171 	if (!pctx)
1172 		return -ENOMEM;
1173 
1174 	pctx->copts = ceph_alloc_options();
1175 	if (!pctx->copts)
1176 		goto nomem;
1177 
1178 	pctx->opts = kzalloc(sizeof(*pctx->opts), GFP_KERNEL);
1179 	if (!pctx->opts)
1180 		goto nomem;
1181 
1182 	fsopt = pctx->opts;
1183 	fsopt->flags = CEPH_MOUNT_OPT_DEFAULT;
1184 
1185 	fsopt->wsize = CEPH_MAX_WRITE_SIZE;
1186 	fsopt->rsize = CEPH_MAX_READ_SIZE;
1187 	fsopt->rasize = CEPH_RASIZE_DEFAULT;
1188 	fsopt->snapdir_name = kstrdup(CEPH_SNAPDIRNAME_DEFAULT, GFP_KERNEL);
1189 	if (!fsopt->snapdir_name)
1190 		goto nomem;
1191 
1192 	fsopt->caps_wanted_delay_min = CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT;
1193 	fsopt->caps_wanted_delay_max = CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT;
1194 	fsopt->max_readdir = CEPH_MAX_READDIR_DEFAULT;
1195 	fsopt->max_readdir_bytes = CEPH_MAX_READDIR_BYTES_DEFAULT;
1196 	fsopt->congestion_kb = default_congestion_kb();
1197 
1198 #ifdef CONFIG_CEPH_FS_POSIX_ACL
1199 	fc->sb_flags |= SB_POSIXACL;
1200 #endif
1201 
1202 	fc->fs_private = pctx;
1203 	fc->ops = &ceph_context_ops;
1204 	return 0;
1205 
1206 nomem:
1207 	destroy_mount_options(pctx->opts);
1208 	ceph_destroy_options(pctx->copts);
1209 	kfree(pctx);
1210 	return -ENOMEM;
1211 }
1212 
1213 static void ceph_kill_sb(struct super_block *s)
1214 {
1215 	struct ceph_fs_client *fsc = ceph_sb_to_client(s);
1216 
1217 	dout("kill_sb %p\n", s);
1218 
1219 	ceph_mdsc_pre_umount(fsc->mdsc);
1220 	flush_fs_workqueues(fsc);
1221 
1222 	kill_anon_super(s);
1223 
1224 	fsc->client->extra_mon_dispatch = NULL;
1225 	ceph_fs_debugfs_cleanup(fsc);
1226 
1227 	ceph_fscache_unregister_fs(fsc);
1228 
1229 	destroy_fs_client(fsc);
1230 }
1231 
1232 static struct file_system_type ceph_fs_type = {
1233 	.owner		= THIS_MODULE,
1234 	.name		= "ceph",
1235 	.init_fs_context = ceph_init_fs_context,
1236 	.kill_sb	= ceph_kill_sb,
1237 	.fs_flags	= FS_RENAME_DOES_D_MOVE,
1238 };
1239 MODULE_ALIAS_FS("ceph");
1240 
1241 int ceph_force_reconnect(struct super_block *sb)
1242 {
1243 	struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
1244 	int err = 0;
1245 
1246 	fsc->mount_state = CEPH_MOUNT_RECOVER;
1247 	__ceph_umount_begin(fsc);
1248 
1249 	/* Make sure all page caches get invalidated.
1250 	 * see remove_session_caps_cb() */
1251 	flush_workqueue(fsc->inode_wq);
1252 
1253 	/* In case that we were blocklisted. This also reset
1254 	 * all mon/osd connections */
1255 	ceph_reset_client_addr(fsc->client);
1256 
1257 	ceph_osdc_clear_abort_err(&fsc->client->osdc);
1258 
1259 	fsc->blocklisted = false;
1260 	fsc->mount_state = CEPH_MOUNT_MOUNTED;
1261 
1262 	if (sb->s_root) {
1263 		err = __ceph_do_getattr(d_inode(sb->s_root), NULL,
1264 					CEPH_STAT_CAP_INODE, true);
1265 	}
1266 	return err;
1267 }
1268 
1269 static int __init init_ceph(void)
1270 {
1271 	int ret = init_caches();
1272 	if (ret)
1273 		goto out;
1274 
1275 	ceph_flock_init();
1276 	ret = register_filesystem(&ceph_fs_type);
1277 	if (ret)
1278 		goto out_caches;
1279 
1280 	pr_info("loaded (mds proto %d)\n", CEPH_MDSC_PROTOCOL);
1281 
1282 	return 0;
1283 
1284 out_caches:
1285 	destroy_caches();
1286 out:
1287 	return ret;
1288 }
1289 
1290 static void __exit exit_ceph(void)
1291 {
1292 	dout("exit_ceph\n");
1293 	unregister_filesystem(&ceph_fs_type);
1294 	destroy_caches();
1295 }
1296 
1297 static int param_set_metrics(const char *val, const struct kernel_param *kp)
1298 {
1299 	struct ceph_fs_client *fsc;
1300 	int ret;
1301 
1302 	ret = param_set_bool(val, kp);
1303 	if (ret) {
1304 		pr_err("Failed to parse sending metrics switch value '%s'\n",
1305 		       val);
1306 		return ret;
1307 	} else if (!disable_send_metrics) {
1308 		// wake up all the mds clients
1309 		spin_lock(&ceph_fsc_lock);
1310 		list_for_each_entry(fsc, &ceph_fsc_list, metric_wakeup) {
1311 			metric_schedule_delayed(&fsc->mdsc->metric);
1312 		}
1313 		spin_unlock(&ceph_fsc_lock);
1314 	}
1315 
1316 	return 0;
1317 }
1318 
1319 static const struct kernel_param_ops param_ops_metrics = {
1320 	.set = param_set_metrics,
1321 	.get = param_get_bool,
1322 };
1323 
1324 bool disable_send_metrics = false;
1325 module_param_cb(disable_send_metrics, &param_ops_metrics, &disable_send_metrics, 0644);
1326 MODULE_PARM_DESC(disable_send_metrics, "Enable sending perf metrics to ceph cluster (default: on)");
1327 
1328 module_init(init_ceph);
1329 module_exit(exit_ceph);
1330 
1331 MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
1332 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
1333 MODULE_AUTHOR("Patience Warnick <patience@newdream.net>");
1334 MODULE_DESCRIPTION("Ceph filesystem for Linux");
1335 MODULE_LICENSE("GPL");
1336