xref: /openbmc/linux/fs/ceph/super.c (revision 2fa5ebe3)
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 #include <uapi/linux/magic.h>
31 
32 static DEFINE_SPINLOCK(ceph_fsc_lock);
33 static LIST_HEAD(ceph_fsc_list);
34 
35 /*
36  * Ceph superblock operations
37  *
38  * Handle the basics of mounting, unmounting.
39  */
40 
41 /*
42  * super ops
43  */
44 static void ceph_put_super(struct super_block *s)
45 {
46 	struct ceph_fs_client *fsc = ceph_sb_to_client(s);
47 
48 	dout("put_super\n");
49 	ceph_mdsc_close_sessions(fsc->mdsc);
50 }
51 
52 static int ceph_statfs(struct dentry *dentry, struct kstatfs *buf)
53 {
54 	struct ceph_fs_client *fsc = ceph_inode_to_client(d_inode(dentry));
55 	struct ceph_mon_client *monc = &fsc->client->monc;
56 	struct ceph_statfs st;
57 	int i, err;
58 	u64 data_pool;
59 
60 	if (fsc->mdsc->mdsmap->m_num_data_pg_pools == 1) {
61 		data_pool = fsc->mdsc->mdsmap->m_data_pg_pools[0];
62 	} else {
63 		data_pool = CEPH_NOPOOL;
64 	}
65 
66 	dout("statfs\n");
67 	err = ceph_monc_do_statfs(monc, data_pool, &st);
68 	if (err < 0)
69 		return err;
70 
71 	/* fill in kstatfs */
72 	buf->f_type = CEPH_SUPER_MAGIC;  /* ?? */
73 
74 	/*
75 	 * Express utilization in terms of large blocks to avoid
76 	 * overflow on 32-bit machines.
77 	 */
78 	buf->f_frsize = 1 << CEPH_BLOCK_SHIFT;
79 
80 	/*
81 	 * By default use root quota for stats; fallback to overall filesystem
82 	 * usage if using 'noquotadf' mount option or if the root dir doesn't
83 	 * have max_bytes quota set.
84 	 */
85 	if (ceph_test_mount_opt(fsc, NOQUOTADF) ||
86 	    !ceph_quota_update_statfs(fsc, buf)) {
87 		buf->f_blocks = le64_to_cpu(st.kb) >> (CEPH_BLOCK_SHIFT-10);
88 		buf->f_bfree = le64_to_cpu(st.kb_avail) >> (CEPH_BLOCK_SHIFT-10);
89 		buf->f_bavail = le64_to_cpu(st.kb_avail) >> (CEPH_BLOCK_SHIFT-10);
90 	}
91 
92 	/*
93 	 * NOTE: for the time being, we make bsize == frsize to humor
94 	 * not-yet-ancient versions of glibc that are broken.
95 	 * Someday, we will probably want to report a real block
96 	 * size...  whatever that may mean for a network file system!
97 	 */
98 	buf->f_bsize = buf->f_frsize;
99 
100 	buf->f_files = le64_to_cpu(st.num_objects);
101 	buf->f_ffree = -1;
102 	buf->f_namelen = NAME_MAX;
103 
104 	/* Must convert the fsid, for consistent values across arches */
105 	buf->f_fsid.val[0] = 0;
106 	mutex_lock(&monc->mutex);
107 	for (i = 0 ; i < sizeof(monc->monmap->fsid) / sizeof(__le32) ; ++i)
108 		buf->f_fsid.val[0] ^= le32_to_cpu(((__le32 *)&monc->monmap->fsid)[i]);
109 	mutex_unlock(&monc->mutex);
110 
111 	/* fold the fs_cluster_id into the upper bits */
112 	buf->f_fsid.val[1] = monc->fs_cluster_id;
113 
114 	return 0;
115 }
116 
117 static int ceph_sync_fs(struct super_block *sb, int wait)
118 {
119 	struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
120 
121 	if (!wait) {
122 		dout("sync_fs (non-blocking)\n");
123 		ceph_flush_dirty_caps(fsc->mdsc);
124 		dout("sync_fs (non-blocking) done\n");
125 		return 0;
126 	}
127 
128 	dout("sync_fs (blocking)\n");
129 	ceph_osdc_sync(&fsc->client->osdc);
130 	ceph_mdsc_sync(fsc->mdsc);
131 	dout("sync_fs (blocking) done\n");
132 	return 0;
133 }
134 
135 /*
136  * mount options
137  */
138 enum {
139 	Opt_wsize,
140 	Opt_rsize,
141 	Opt_rasize,
142 	Opt_caps_wanted_delay_min,
143 	Opt_caps_wanted_delay_max,
144 	Opt_caps_max,
145 	Opt_readdir_max_entries,
146 	Opt_readdir_max_bytes,
147 	Opt_congestion_kb,
148 	/* int args above */
149 	Opt_snapdirname,
150 	Opt_mds_namespace,
151 	Opt_recover_session,
152 	Opt_source,
153 	Opt_mon_addr,
154 	/* string args above */
155 	Opt_dirstat,
156 	Opt_rbytes,
157 	Opt_asyncreaddir,
158 	Opt_dcache,
159 	Opt_ino32,
160 	Opt_fscache,
161 	Opt_poolperm,
162 	Opt_require_active_mds,
163 	Opt_acl,
164 	Opt_quotadf,
165 	Opt_copyfrom,
166 	Opt_wsync,
167 	Opt_pagecache,
168 };
169 
170 enum ceph_recover_session_mode {
171 	ceph_recover_session_no,
172 	ceph_recover_session_clean
173 };
174 
175 static const struct constant_table ceph_param_recover[] = {
176 	{ "no",		ceph_recover_session_no },
177 	{ "clean",	ceph_recover_session_clean },
178 	{}
179 };
180 
181 static const struct fs_parameter_spec ceph_mount_parameters[] = {
182 	fsparam_flag_no ("acl",				Opt_acl),
183 	fsparam_flag_no ("asyncreaddir",		Opt_asyncreaddir),
184 	fsparam_s32	("caps_max",			Opt_caps_max),
185 	fsparam_u32	("caps_wanted_delay_max",	Opt_caps_wanted_delay_max),
186 	fsparam_u32	("caps_wanted_delay_min",	Opt_caps_wanted_delay_min),
187 	fsparam_u32	("write_congestion_kb",		Opt_congestion_kb),
188 	fsparam_flag_no ("copyfrom",			Opt_copyfrom),
189 	fsparam_flag_no ("dcache",			Opt_dcache),
190 	fsparam_flag_no ("dirstat",			Opt_dirstat),
191 	fsparam_flag_no	("fsc",				Opt_fscache), // fsc|nofsc
192 	fsparam_string	("fsc",				Opt_fscache), // fsc=...
193 	fsparam_flag_no ("ino32",			Opt_ino32),
194 	fsparam_string	("mds_namespace",		Opt_mds_namespace),
195 	fsparam_flag_no ("poolperm",			Opt_poolperm),
196 	fsparam_flag_no ("quotadf",			Opt_quotadf),
197 	fsparam_u32	("rasize",			Opt_rasize),
198 	fsparam_flag_no ("rbytes",			Opt_rbytes),
199 	fsparam_u32	("readdir_max_bytes",		Opt_readdir_max_bytes),
200 	fsparam_u32	("readdir_max_entries",		Opt_readdir_max_entries),
201 	fsparam_enum	("recover_session",		Opt_recover_session, ceph_param_recover),
202 	fsparam_flag_no ("require_active_mds",		Opt_require_active_mds),
203 	fsparam_u32	("rsize",			Opt_rsize),
204 	fsparam_string	("snapdirname",			Opt_snapdirname),
205 	fsparam_string	("source",			Opt_source),
206 	fsparam_string	("mon_addr",			Opt_mon_addr),
207 	fsparam_u32	("wsize",			Opt_wsize),
208 	fsparam_flag_no	("wsync",			Opt_wsync),
209 	fsparam_flag_no	("pagecache",			Opt_pagecache),
210 	{}
211 };
212 
213 struct ceph_parse_opts_ctx {
214 	struct ceph_options		*copts;
215 	struct ceph_mount_options	*opts;
216 };
217 
218 /*
219  * Remove adjacent slashes and then the trailing slash, unless it is
220  * the only remaining character.
221  *
222  * E.g. "//dir1////dir2///" --> "/dir1/dir2", "///" --> "/".
223  */
224 static void canonicalize_path(char *path)
225 {
226 	int i, j = 0;
227 
228 	for (i = 0; path[i] != '\0'; i++) {
229 		if (path[i] != '/' || j < 1 || path[j - 1] != '/')
230 			path[j++] = path[i];
231 	}
232 
233 	if (j > 1 && path[j - 1] == '/')
234 		j--;
235 	path[j] = '\0';
236 }
237 
238 /*
239  * Check if the mds namespace in ceph_mount_options matches
240  * the passed in namespace string. First time match (when
241  * ->mds_namespace is NULL) is treated specially, since
242  * ->mds_namespace needs to be initialized by the caller.
243  */
244 static int namespace_equals(struct ceph_mount_options *fsopt,
245 			    const char *namespace, size_t len)
246 {
247 	return !(fsopt->mds_namespace &&
248 		 (strlen(fsopt->mds_namespace) != len ||
249 		  strncmp(fsopt->mds_namespace, namespace, len)));
250 }
251 
252 static int ceph_parse_old_source(const char *dev_name, const char *dev_name_end,
253 				 struct fs_context *fc)
254 {
255 	int r;
256 	struct ceph_parse_opts_ctx *pctx = fc->fs_private;
257 	struct ceph_mount_options *fsopt = pctx->opts;
258 
259 	if (*dev_name_end != ':')
260 		return invalfc(fc, "separator ':' missing in source");
261 
262 	r = ceph_parse_mon_ips(dev_name, dev_name_end - dev_name,
263 			       pctx->copts, fc->log.log, ',');
264 	if (r)
265 		return r;
266 
267 	fsopt->new_dev_syntax = false;
268 	return 0;
269 }
270 
271 static int ceph_parse_new_source(const char *dev_name, const char *dev_name_end,
272 				 struct fs_context *fc)
273 {
274 	size_t len;
275 	struct ceph_fsid fsid;
276 	struct ceph_parse_opts_ctx *pctx = fc->fs_private;
277 	struct ceph_mount_options *fsopt = pctx->opts;
278 	char *fsid_start, *fs_name_start;
279 
280 	if (*dev_name_end != '=') {
281 		dout("separator '=' missing in source");
282 		return -EINVAL;
283 	}
284 
285 	fsid_start = strchr(dev_name, '@');
286 	if (!fsid_start)
287 		return invalfc(fc, "missing cluster fsid");
288 	++fsid_start; /* start of cluster fsid */
289 
290 	fs_name_start = strchr(fsid_start, '.');
291 	if (!fs_name_start)
292 		return invalfc(fc, "missing file system name");
293 
294 	if (ceph_parse_fsid(fsid_start, &fsid))
295 		return invalfc(fc, "Invalid FSID");
296 
297 	++fs_name_start; /* start of file system name */
298 	len = dev_name_end - fs_name_start;
299 
300 	if (!namespace_equals(fsopt, fs_name_start, len))
301 		return invalfc(fc, "Mismatching mds_namespace");
302 	kfree(fsopt->mds_namespace);
303 	fsopt->mds_namespace = kstrndup(fs_name_start, len, GFP_KERNEL);
304 	if (!fsopt->mds_namespace)
305 		return -ENOMEM;
306 	dout("file system (mds namespace) '%s'\n", fsopt->mds_namespace);
307 
308 	fsopt->new_dev_syntax = true;
309 	return 0;
310 }
311 
312 /*
313  * Parse the source parameter for new device format. Distinguish the device
314  * spec from the path. Try parsing new device format and fallback to old
315  * format if needed.
316  *
317  * New device syntax will looks like:
318  *     <device_spec>=/<path>
319  * where
320  *     <device_spec> is name@fsid.fsname
321  *     <path> is optional, but if present must begin with '/'
322  * (monitor addresses are passed via mount option)
323  *
324  * Old device syntax is:
325  *     <server_spec>[,<server_spec>...]:[<path>]
326  * where
327  *     <server_spec> is <ip>[:<port>]
328  *     <path> is optional, but if present must begin with '/'
329  */
330 static int ceph_parse_source(struct fs_parameter *param, struct fs_context *fc)
331 {
332 	struct ceph_parse_opts_ctx *pctx = fc->fs_private;
333 	struct ceph_mount_options *fsopt = pctx->opts;
334 	char *dev_name = param->string, *dev_name_end;
335 	int ret;
336 
337 	dout("%s '%s'\n", __func__, dev_name);
338 	if (!dev_name || !*dev_name)
339 		return invalfc(fc, "Empty source");
340 
341 	dev_name_end = strchr(dev_name, '/');
342 	if (dev_name_end) {
343 		/*
344 		 * The server_path will include the whole chars from userland
345 		 * including the leading '/'.
346 		 */
347 		kfree(fsopt->server_path);
348 		fsopt->server_path = kstrdup(dev_name_end, GFP_KERNEL);
349 		if (!fsopt->server_path)
350 			return -ENOMEM;
351 
352 		canonicalize_path(fsopt->server_path);
353 	} else {
354 		dev_name_end = dev_name + strlen(dev_name);
355 	}
356 
357 	dev_name_end--;		/* back up to separator */
358 	if (dev_name_end < dev_name)
359 		return invalfc(fc, "Path missing in source");
360 
361 	dout("device name '%.*s'\n", (int)(dev_name_end - dev_name), dev_name);
362 	if (fsopt->server_path)
363 		dout("server path '%s'\n", fsopt->server_path);
364 
365 	dout("trying new device syntax");
366 	ret = ceph_parse_new_source(dev_name, dev_name_end, fc);
367 	if (ret) {
368 		if (ret != -EINVAL)
369 			return ret;
370 		dout("trying old device syntax");
371 		ret = ceph_parse_old_source(dev_name, dev_name_end, fc);
372 		if (ret)
373 			return ret;
374 	}
375 
376 	fc->source = param->string;
377 	param->string = NULL;
378 	return 0;
379 }
380 
381 static int ceph_parse_mon_addr(struct fs_parameter *param,
382 			       struct fs_context *fc)
383 {
384 	struct ceph_parse_opts_ctx *pctx = fc->fs_private;
385 	struct ceph_mount_options *fsopt = pctx->opts;
386 
387 	kfree(fsopt->mon_addr);
388 	fsopt->mon_addr = param->string;
389 	param->string = NULL;
390 
391 	return ceph_parse_mon_ips(fsopt->mon_addr, strlen(fsopt->mon_addr),
392 				  pctx->copts, fc->log.log, '/');
393 }
394 
395 static int ceph_parse_mount_param(struct fs_context *fc,
396 				  struct fs_parameter *param)
397 {
398 	struct ceph_parse_opts_ctx *pctx = fc->fs_private;
399 	struct ceph_mount_options *fsopt = pctx->opts;
400 	struct fs_parse_result result;
401 	unsigned int mode;
402 	int token, ret;
403 
404 	ret = ceph_parse_param(param, pctx->copts, fc->log.log);
405 	if (ret != -ENOPARAM)
406 		return ret;
407 
408 	token = fs_parse(fc, ceph_mount_parameters, param, &result);
409 	dout("%s fs_parse '%s' token %d\n", __func__, param->key, token);
410 	if (token < 0)
411 		return token;
412 
413 	switch (token) {
414 	case Opt_snapdirname:
415 		kfree(fsopt->snapdir_name);
416 		fsopt->snapdir_name = param->string;
417 		param->string = NULL;
418 		break;
419 	case Opt_mds_namespace:
420 		if (!namespace_equals(fsopt, param->string, strlen(param->string)))
421 			return invalfc(fc, "Mismatching mds_namespace");
422 		kfree(fsopt->mds_namespace);
423 		fsopt->mds_namespace = param->string;
424 		param->string = NULL;
425 		break;
426 	case Opt_recover_session:
427 		mode = result.uint_32;
428 		if (mode == ceph_recover_session_no)
429 			fsopt->flags &= ~CEPH_MOUNT_OPT_CLEANRECOVER;
430 		else if (mode == ceph_recover_session_clean)
431 			fsopt->flags |= CEPH_MOUNT_OPT_CLEANRECOVER;
432 		else
433 			BUG();
434 		break;
435 	case Opt_source:
436 		if (fc->source)
437 			return invalfc(fc, "Multiple sources specified");
438 		return ceph_parse_source(param, fc);
439 	case Opt_mon_addr:
440 		return ceph_parse_mon_addr(param, fc);
441 	case Opt_wsize:
442 		if (result.uint_32 < PAGE_SIZE ||
443 		    result.uint_32 > CEPH_MAX_WRITE_SIZE)
444 			goto out_of_range;
445 		fsopt->wsize = ALIGN(result.uint_32, PAGE_SIZE);
446 		break;
447 	case Opt_rsize:
448 		if (result.uint_32 < PAGE_SIZE ||
449 		    result.uint_32 > CEPH_MAX_READ_SIZE)
450 			goto out_of_range;
451 		fsopt->rsize = ALIGN(result.uint_32, PAGE_SIZE);
452 		break;
453 	case Opt_rasize:
454 		fsopt->rasize = ALIGN(result.uint_32, PAGE_SIZE);
455 		break;
456 	case Opt_caps_wanted_delay_min:
457 		if (result.uint_32 < 1)
458 			goto out_of_range;
459 		fsopt->caps_wanted_delay_min = result.uint_32;
460 		break;
461 	case Opt_caps_wanted_delay_max:
462 		if (result.uint_32 < 1)
463 			goto out_of_range;
464 		fsopt->caps_wanted_delay_max = result.uint_32;
465 		break;
466 	case Opt_caps_max:
467 		if (result.int_32 < 0)
468 			goto out_of_range;
469 		fsopt->caps_max = result.int_32;
470 		break;
471 	case Opt_readdir_max_entries:
472 		if (result.uint_32 < 1)
473 			goto out_of_range;
474 		fsopt->max_readdir = result.uint_32;
475 		break;
476 	case Opt_readdir_max_bytes:
477 		if (result.uint_32 < PAGE_SIZE && result.uint_32 != 0)
478 			goto out_of_range;
479 		fsopt->max_readdir_bytes = result.uint_32;
480 		break;
481 	case Opt_congestion_kb:
482 		if (result.uint_32 < 1024) /* at least 1M */
483 			goto out_of_range;
484 		fsopt->congestion_kb = result.uint_32;
485 		break;
486 	case Opt_dirstat:
487 		if (!result.negated)
488 			fsopt->flags |= CEPH_MOUNT_OPT_DIRSTAT;
489 		else
490 			fsopt->flags &= ~CEPH_MOUNT_OPT_DIRSTAT;
491 		break;
492 	case Opt_rbytes:
493 		if (!result.negated)
494 			fsopt->flags |= CEPH_MOUNT_OPT_RBYTES;
495 		else
496 			fsopt->flags &= ~CEPH_MOUNT_OPT_RBYTES;
497 		break;
498 	case Opt_asyncreaddir:
499 		if (!result.negated)
500 			fsopt->flags &= ~CEPH_MOUNT_OPT_NOASYNCREADDIR;
501 		else
502 			fsopt->flags |= CEPH_MOUNT_OPT_NOASYNCREADDIR;
503 		break;
504 	case Opt_dcache:
505 		if (!result.negated)
506 			fsopt->flags |= CEPH_MOUNT_OPT_DCACHE;
507 		else
508 			fsopt->flags &= ~CEPH_MOUNT_OPT_DCACHE;
509 		break;
510 	case Opt_ino32:
511 		if (!result.negated)
512 			fsopt->flags |= CEPH_MOUNT_OPT_INO32;
513 		else
514 			fsopt->flags &= ~CEPH_MOUNT_OPT_INO32;
515 		break;
516 
517 	case Opt_fscache:
518 #ifdef CONFIG_CEPH_FSCACHE
519 		kfree(fsopt->fscache_uniq);
520 		fsopt->fscache_uniq = NULL;
521 		if (result.negated) {
522 			fsopt->flags &= ~CEPH_MOUNT_OPT_FSCACHE;
523 		} else {
524 			fsopt->flags |= CEPH_MOUNT_OPT_FSCACHE;
525 			fsopt->fscache_uniq = param->string;
526 			param->string = NULL;
527 		}
528 		break;
529 #else
530 		return invalfc(fc, "fscache support is disabled");
531 #endif
532 	case Opt_poolperm:
533 		if (!result.negated)
534 			fsopt->flags &= ~CEPH_MOUNT_OPT_NOPOOLPERM;
535 		else
536 			fsopt->flags |= CEPH_MOUNT_OPT_NOPOOLPERM;
537 		break;
538 	case Opt_require_active_mds:
539 		if (!result.negated)
540 			fsopt->flags &= ~CEPH_MOUNT_OPT_MOUNTWAIT;
541 		else
542 			fsopt->flags |= CEPH_MOUNT_OPT_MOUNTWAIT;
543 		break;
544 	case Opt_quotadf:
545 		if (!result.negated)
546 			fsopt->flags &= ~CEPH_MOUNT_OPT_NOQUOTADF;
547 		else
548 			fsopt->flags |= CEPH_MOUNT_OPT_NOQUOTADF;
549 		break;
550 	case Opt_copyfrom:
551 		if (!result.negated)
552 			fsopt->flags &= ~CEPH_MOUNT_OPT_NOCOPYFROM;
553 		else
554 			fsopt->flags |= CEPH_MOUNT_OPT_NOCOPYFROM;
555 		break;
556 	case Opt_acl:
557 		if (!result.negated) {
558 #ifdef CONFIG_CEPH_FS_POSIX_ACL
559 			fc->sb_flags |= SB_POSIXACL;
560 #else
561 			return invalfc(fc, "POSIX ACL support is disabled");
562 #endif
563 		} else {
564 			fc->sb_flags &= ~SB_POSIXACL;
565 		}
566 		break;
567 	case Opt_wsync:
568 		if (!result.negated)
569 			fsopt->flags &= ~CEPH_MOUNT_OPT_ASYNC_DIROPS;
570 		else
571 			fsopt->flags |= CEPH_MOUNT_OPT_ASYNC_DIROPS;
572 		break;
573 	case Opt_pagecache:
574 		if (result.negated)
575 			fsopt->flags |= CEPH_MOUNT_OPT_NOPAGECACHE;
576 		else
577 			fsopt->flags &= ~CEPH_MOUNT_OPT_NOPAGECACHE;
578 		break;
579 	default:
580 		BUG();
581 	}
582 	return 0;
583 
584 out_of_range:
585 	return invalfc(fc, "%s out of range", param->key);
586 }
587 
588 static void destroy_mount_options(struct ceph_mount_options *args)
589 {
590 	dout("destroy_mount_options %p\n", args);
591 	if (!args)
592 		return;
593 
594 	kfree(args->snapdir_name);
595 	kfree(args->mds_namespace);
596 	kfree(args->server_path);
597 	kfree(args->fscache_uniq);
598 	kfree(args->mon_addr);
599 	kfree(args);
600 }
601 
602 static int strcmp_null(const char *s1, const char *s2)
603 {
604 	if (!s1 && !s2)
605 		return 0;
606 	if (s1 && !s2)
607 		return -1;
608 	if (!s1 && s2)
609 		return 1;
610 	return strcmp(s1, s2);
611 }
612 
613 static int compare_mount_options(struct ceph_mount_options *new_fsopt,
614 				 struct ceph_options *new_opt,
615 				 struct ceph_fs_client *fsc)
616 {
617 	struct ceph_mount_options *fsopt1 = new_fsopt;
618 	struct ceph_mount_options *fsopt2 = fsc->mount_options;
619 	int ofs = offsetof(struct ceph_mount_options, snapdir_name);
620 	int ret;
621 
622 	ret = memcmp(fsopt1, fsopt2, ofs);
623 	if (ret)
624 		return ret;
625 
626 	ret = strcmp_null(fsopt1->snapdir_name, fsopt2->snapdir_name);
627 	if (ret)
628 		return ret;
629 
630 	ret = strcmp_null(fsopt1->mds_namespace, fsopt2->mds_namespace);
631 	if (ret)
632 		return ret;
633 
634 	ret = strcmp_null(fsopt1->server_path, fsopt2->server_path);
635 	if (ret)
636 		return ret;
637 
638 	ret = strcmp_null(fsopt1->fscache_uniq, fsopt2->fscache_uniq);
639 	if (ret)
640 		return ret;
641 
642 	ret = strcmp_null(fsopt1->mon_addr, fsopt2->mon_addr);
643 	if (ret)
644 		return ret;
645 
646 	return ceph_compare_options(new_opt, fsc->client);
647 }
648 
649 /**
650  * ceph_show_options - Show mount options in /proc/mounts
651  * @m: seq_file to write to
652  * @root: root of that (sub)tree
653  */
654 static int ceph_show_options(struct seq_file *m, struct dentry *root)
655 {
656 	struct ceph_fs_client *fsc = ceph_sb_to_client(root->d_sb);
657 	struct ceph_mount_options *fsopt = fsc->mount_options;
658 	size_t pos;
659 	int ret;
660 
661 	/* a comma between MNT/MS and client options */
662 	seq_putc(m, ',');
663 	pos = m->count;
664 
665 	ret = ceph_print_client_options(m, fsc->client, false);
666 	if (ret)
667 		return ret;
668 
669 	/* retract our comma if no client options */
670 	if (m->count == pos)
671 		m->count--;
672 
673 	if (fsopt->flags & CEPH_MOUNT_OPT_DIRSTAT)
674 		seq_puts(m, ",dirstat");
675 	if ((fsopt->flags & CEPH_MOUNT_OPT_RBYTES))
676 		seq_puts(m, ",rbytes");
677 	if (fsopt->flags & CEPH_MOUNT_OPT_NOASYNCREADDIR)
678 		seq_puts(m, ",noasyncreaddir");
679 	if ((fsopt->flags & CEPH_MOUNT_OPT_DCACHE) == 0)
680 		seq_puts(m, ",nodcache");
681 	if (fsopt->flags & CEPH_MOUNT_OPT_INO32)
682 		seq_puts(m, ",ino32");
683 	if (fsopt->flags & CEPH_MOUNT_OPT_FSCACHE) {
684 		seq_show_option(m, "fsc", fsopt->fscache_uniq);
685 	}
686 	if (fsopt->flags & CEPH_MOUNT_OPT_NOPOOLPERM)
687 		seq_puts(m, ",nopoolperm");
688 	if (fsopt->flags & CEPH_MOUNT_OPT_NOQUOTADF)
689 		seq_puts(m, ",noquotadf");
690 
691 #ifdef CONFIG_CEPH_FS_POSIX_ACL
692 	if (root->d_sb->s_flags & SB_POSIXACL)
693 		seq_puts(m, ",acl");
694 	else
695 		seq_puts(m, ",noacl");
696 #endif
697 
698 	if ((fsopt->flags & CEPH_MOUNT_OPT_NOCOPYFROM) == 0)
699 		seq_puts(m, ",copyfrom");
700 
701 	/* dump mds_namespace when old device syntax is in use */
702 	if (fsopt->mds_namespace && !fsopt->new_dev_syntax)
703 		seq_show_option(m, "mds_namespace", fsopt->mds_namespace);
704 
705 	if (fsopt->mon_addr)
706 		seq_printf(m, ",mon_addr=%s", fsopt->mon_addr);
707 
708 	if (fsopt->flags & CEPH_MOUNT_OPT_CLEANRECOVER)
709 		seq_show_option(m, "recover_session", "clean");
710 
711 	if (!(fsopt->flags & CEPH_MOUNT_OPT_ASYNC_DIROPS))
712 		seq_puts(m, ",wsync");
713 
714 	if (fsopt->flags & CEPH_MOUNT_OPT_NOPAGECACHE)
715 		seq_puts(m, ",nopagecache");
716 
717 	if (fsopt->wsize != CEPH_MAX_WRITE_SIZE)
718 		seq_printf(m, ",wsize=%u", fsopt->wsize);
719 	if (fsopt->rsize != CEPH_MAX_READ_SIZE)
720 		seq_printf(m, ",rsize=%u", fsopt->rsize);
721 	if (fsopt->rasize != CEPH_RASIZE_DEFAULT)
722 		seq_printf(m, ",rasize=%u", fsopt->rasize);
723 	if (fsopt->congestion_kb != default_congestion_kb())
724 		seq_printf(m, ",write_congestion_kb=%u", fsopt->congestion_kb);
725 	if (fsopt->caps_max)
726 		seq_printf(m, ",caps_max=%d", fsopt->caps_max);
727 	if (fsopt->caps_wanted_delay_min != CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT)
728 		seq_printf(m, ",caps_wanted_delay_min=%u",
729 			 fsopt->caps_wanted_delay_min);
730 	if (fsopt->caps_wanted_delay_max != CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT)
731 		seq_printf(m, ",caps_wanted_delay_max=%u",
732 			   fsopt->caps_wanted_delay_max);
733 	if (fsopt->max_readdir != CEPH_MAX_READDIR_DEFAULT)
734 		seq_printf(m, ",readdir_max_entries=%u", fsopt->max_readdir);
735 	if (fsopt->max_readdir_bytes != CEPH_MAX_READDIR_BYTES_DEFAULT)
736 		seq_printf(m, ",readdir_max_bytes=%u", fsopt->max_readdir_bytes);
737 	if (strcmp(fsopt->snapdir_name, CEPH_SNAPDIRNAME_DEFAULT))
738 		seq_show_option(m, "snapdirname", fsopt->snapdir_name);
739 
740 	return 0;
741 }
742 
743 /*
744  * handle any mon messages the standard library doesn't understand.
745  * return error if we don't either.
746  */
747 static int extra_mon_dispatch(struct ceph_client *client, struct ceph_msg *msg)
748 {
749 	struct ceph_fs_client *fsc = client->private;
750 	int type = le16_to_cpu(msg->hdr.type);
751 
752 	switch (type) {
753 	case CEPH_MSG_MDS_MAP:
754 		ceph_mdsc_handle_mdsmap(fsc->mdsc, msg);
755 		return 0;
756 	case CEPH_MSG_FS_MAP_USER:
757 		ceph_mdsc_handle_fsmap(fsc->mdsc, msg);
758 		return 0;
759 	default:
760 		return -1;
761 	}
762 }
763 
764 /*
765  * create a new fs client
766  *
767  * Success or not, this function consumes @fsopt and @opt.
768  */
769 static struct ceph_fs_client *create_fs_client(struct ceph_mount_options *fsopt,
770 					struct ceph_options *opt)
771 {
772 	struct ceph_fs_client *fsc;
773 	int err;
774 
775 	fsc = kzalloc(sizeof(*fsc), GFP_KERNEL);
776 	if (!fsc) {
777 		err = -ENOMEM;
778 		goto fail;
779 	}
780 
781 	fsc->client = ceph_create_client(opt, fsc);
782 	if (IS_ERR(fsc->client)) {
783 		err = PTR_ERR(fsc->client);
784 		goto fail;
785 	}
786 	opt = NULL; /* fsc->client now owns this */
787 
788 	fsc->client->extra_mon_dispatch = extra_mon_dispatch;
789 	ceph_set_opt(fsc->client, ABORT_ON_FULL);
790 
791 	if (!fsopt->mds_namespace) {
792 		ceph_monc_want_map(&fsc->client->monc, CEPH_SUB_MDSMAP,
793 				   0, true);
794 	} else {
795 		ceph_monc_want_map(&fsc->client->monc, CEPH_SUB_FSMAP,
796 				   0, false);
797 	}
798 
799 	fsc->mount_options = fsopt;
800 
801 	fsc->sb = NULL;
802 	fsc->mount_state = CEPH_MOUNT_MOUNTING;
803 	fsc->filp_gen = 1;
804 	fsc->have_copy_from2 = true;
805 
806 	atomic_long_set(&fsc->writeback_count, 0);
807 	fsc->write_congested = false;
808 
809 	err = -ENOMEM;
810 	/*
811 	 * The number of concurrent works can be high but they don't need
812 	 * to be processed in parallel, limit concurrency.
813 	 */
814 	fsc->inode_wq = alloc_workqueue("ceph-inode", WQ_UNBOUND, 0);
815 	if (!fsc->inode_wq)
816 		goto fail_client;
817 	fsc->cap_wq = alloc_workqueue("ceph-cap", 0, 1);
818 	if (!fsc->cap_wq)
819 		goto fail_inode_wq;
820 
821 	hash_init(fsc->async_unlink_conflict);
822 	spin_lock_init(&fsc->async_unlink_conflict_lock);
823 
824 	spin_lock(&ceph_fsc_lock);
825 	list_add_tail(&fsc->metric_wakeup, &ceph_fsc_list);
826 	spin_unlock(&ceph_fsc_lock);
827 
828 	return fsc;
829 
830 fail_inode_wq:
831 	destroy_workqueue(fsc->inode_wq);
832 fail_client:
833 	ceph_destroy_client(fsc->client);
834 fail:
835 	kfree(fsc);
836 	if (opt)
837 		ceph_destroy_options(opt);
838 	destroy_mount_options(fsopt);
839 	return ERR_PTR(err);
840 }
841 
842 static void flush_fs_workqueues(struct ceph_fs_client *fsc)
843 {
844 	flush_workqueue(fsc->inode_wq);
845 	flush_workqueue(fsc->cap_wq);
846 }
847 
848 static void destroy_fs_client(struct ceph_fs_client *fsc)
849 {
850 	dout("destroy_fs_client %p\n", fsc);
851 
852 	spin_lock(&ceph_fsc_lock);
853 	list_del(&fsc->metric_wakeup);
854 	spin_unlock(&ceph_fsc_lock);
855 
856 	ceph_mdsc_destroy(fsc);
857 	destroy_workqueue(fsc->inode_wq);
858 	destroy_workqueue(fsc->cap_wq);
859 
860 	destroy_mount_options(fsc->mount_options);
861 
862 	ceph_destroy_client(fsc->client);
863 
864 	kfree(fsc);
865 	dout("destroy_fs_client %p done\n", fsc);
866 }
867 
868 /*
869  * caches
870  */
871 struct kmem_cache *ceph_inode_cachep;
872 struct kmem_cache *ceph_cap_cachep;
873 struct kmem_cache *ceph_cap_snap_cachep;
874 struct kmem_cache *ceph_cap_flush_cachep;
875 struct kmem_cache *ceph_dentry_cachep;
876 struct kmem_cache *ceph_file_cachep;
877 struct kmem_cache *ceph_dir_file_cachep;
878 struct kmem_cache *ceph_mds_request_cachep;
879 mempool_t *ceph_wb_pagevec_pool;
880 
881 static void ceph_inode_init_once(void *foo)
882 {
883 	struct ceph_inode_info *ci = foo;
884 	inode_init_once(&ci->netfs.inode);
885 }
886 
887 static int __init init_caches(void)
888 {
889 	int error = -ENOMEM;
890 
891 	ceph_inode_cachep = kmem_cache_create("ceph_inode_info",
892 				      sizeof(struct ceph_inode_info),
893 				      __alignof__(struct ceph_inode_info),
894 				      SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
895 				      SLAB_ACCOUNT, ceph_inode_init_once);
896 	if (!ceph_inode_cachep)
897 		return -ENOMEM;
898 
899 	ceph_cap_cachep = KMEM_CACHE(ceph_cap, SLAB_MEM_SPREAD);
900 	if (!ceph_cap_cachep)
901 		goto bad_cap;
902 	ceph_cap_snap_cachep = KMEM_CACHE(ceph_cap_snap, SLAB_MEM_SPREAD);
903 	if (!ceph_cap_snap_cachep)
904 		goto bad_cap_snap;
905 	ceph_cap_flush_cachep = KMEM_CACHE(ceph_cap_flush,
906 					   SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
907 	if (!ceph_cap_flush_cachep)
908 		goto bad_cap_flush;
909 
910 	ceph_dentry_cachep = KMEM_CACHE(ceph_dentry_info,
911 					SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
912 	if (!ceph_dentry_cachep)
913 		goto bad_dentry;
914 
915 	ceph_file_cachep = KMEM_CACHE(ceph_file_info, SLAB_MEM_SPREAD);
916 	if (!ceph_file_cachep)
917 		goto bad_file;
918 
919 	ceph_dir_file_cachep = KMEM_CACHE(ceph_dir_file_info, SLAB_MEM_SPREAD);
920 	if (!ceph_dir_file_cachep)
921 		goto bad_dir_file;
922 
923 	ceph_mds_request_cachep = KMEM_CACHE(ceph_mds_request, SLAB_MEM_SPREAD);
924 	if (!ceph_mds_request_cachep)
925 		goto bad_mds_req;
926 
927 	ceph_wb_pagevec_pool = mempool_create_kmalloc_pool(10, CEPH_MAX_WRITE_SIZE >> PAGE_SHIFT);
928 	if (!ceph_wb_pagevec_pool)
929 		goto bad_pagevec_pool;
930 
931 	return 0;
932 
933 bad_pagevec_pool:
934 	kmem_cache_destroy(ceph_mds_request_cachep);
935 bad_mds_req:
936 	kmem_cache_destroy(ceph_dir_file_cachep);
937 bad_dir_file:
938 	kmem_cache_destroy(ceph_file_cachep);
939 bad_file:
940 	kmem_cache_destroy(ceph_dentry_cachep);
941 bad_dentry:
942 	kmem_cache_destroy(ceph_cap_flush_cachep);
943 bad_cap_flush:
944 	kmem_cache_destroy(ceph_cap_snap_cachep);
945 bad_cap_snap:
946 	kmem_cache_destroy(ceph_cap_cachep);
947 bad_cap:
948 	kmem_cache_destroy(ceph_inode_cachep);
949 	return error;
950 }
951 
952 static void destroy_caches(void)
953 {
954 	/*
955 	 * Make sure all delayed rcu free inodes are flushed before we
956 	 * destroy cache.
957 	 */
958 	rcu_barrier();
959 
960 	kmem_cache_destroy(ceph_inode_cachep);
961 	kmem_cache_destroy(ceph_cap_cachep);
962 	kmem_cache_destroy(ceph_cap_snap_cachep);
963 	kmem_cache_destroy(ceph_cap_flush_cachep);
964 	kmem_cache_destroy(ceph_dentry_cachep);
965 	kmem_cache_destroy(ceph_file_cachep);
966 	kmem_cache_destroy(ceph_dir_file_cachep);
967 	kmem_cache_destroy(ceph_mds_request_cachep);
968 	mempool_destroy(ceph_wb_pagevec_pool);
969 }
970 
971 static void __ceph_umount_begin(struct ceph_fs_client *fsc)
972 {
973 	ceph_osdc_abort_requests(&fsc->client->osdc, -EIO);
974 	ceph_mdsc_force_umount(fsc->mdsc);
975 	fsc->filp_gen++; // invalidate open files
976 }
977 
978 /*
979  * ceph_umount_begin - initiate forced umount.  Tear down the
980  * mount, skipping steps that may hang while waiting for server(s).
981  */
982 void ceph_umount_begin(struct super_block *sb)
983 {
984 	struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
985 
986 	dout("ceph_umount_begin - starting forced umount\n");
987 	if (!fsc)
988 		return;
989 	fsc->mount_state = CEPH_MOUNT_SHUTDOWN;
990 	__ceph_umount_begin(fsc);
991 }
992 
993 static const struct super_operations ceph_super_ops = {
994 	.alloc_inode	= ceph_alloc_inode,
995 	.free_inode	= ceph_free_inode,
996 	.write_inode    = ceph_write_inode,
997 	.drop_inode	= generic_delete_inode,
998 	.evict_inode	= ceph_evict_inode,
999 	.sync_fs        = ceph_sync_fs,
1000 	.put_super	= ceph_put_super,
1001 	.show_options   = ceph_show_options,
1002 	.statfs		= ceph_statfs,
1003 	.umount_begin   = ceph_umount_begin,
1004 };
1005 
1006 /*
1007  * Bootstrap mount by opening the root directory.  Note the mount
1008  * @started time from caller, and time out if this takes too long.
1009  */
1010 static struct dentry *open_root_dentry(struct ceph_fs_client *fsc,
1011 				       const char *path,
1012 				       unsigned long started)
1013 {
1014 	struct ceph_mds_client *mdsc = fsc->mdsc;
1015 	struct ceph_mds_request *req = NULL;
1016 	int err;
1017 	struct dentry *root;
1018 
1019 	/* open dir */
1020 	dout("open_root_inode opening '%s'\n", path);
1021 	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_GETATTR, USE_ANY_MDS);
1022 	if (IS_ERR(req))
1023 		return ERR_CAST(req);
1024 	req->r_path1 = kstrdup(path, GFP_NOFS);
1025 	if (!req->r_path1) {
1026 		root = ERR_PTR(-ENOMEM);
1027 		goto out;
1028 	}
1029 
1030 	req->r_ino1.ino = CEPH_INO_ROOT;
1031 	req->r_ino1.snap = CEPH_NOSNAP;
1032 	req->r_started = started;
1033 	req->r_timeout = fsc->client->options->mount_timeout;
1034 	req->r_args.getattr.mask = cpu_to_le32(CEPH_STAT_CAP_INODE);
1035 	req->r_num_caps = 2;
1036 	err = ceph_mdsc_do_request(mdsc, NULL, req);
1037 	if (err == 0) {
1038 		struct inode *inode = req->r_target_inode;
1039 		req->r_target_inode = NULL;
1040 		dout("open_root_inode success\n");
1041 		root = d_make_root(inode);
1042 		if (!root) {
1043 			root = ERR_PTR(-ENOMEM);
1044 			goto out;
1045 		}
1046 		dout("open_root_inode success, root dentry is %p\n", root);
1047 	} else {
1048 		root = ERR_PTR(err);
1049 	}
1050 out:
1051 	ceph_mdsc_put_request(req);
1052 	return root;
1053 }
1054 
1055 /*
1056  * mount: join the ceph cluster, and open root directory.
1057  */
1058 static struct dentry *ceph_real_mount(struct ceph_fs_client *fsc,
1059 				      struct fs_context *fc)
1060 {
1061 	int err;
1062 	unsigned long started = jiffies;  /* note the start time */
1063 	struct dentry *root;
1064 
1065 	dout("mount start %p\n", fsc);
1066 	mutex_lock(&fsc->client->mount_mutex);
1067 
1068 	if (!fsc->sb->s_root) {
1069 		const char *path = fsc->mount_options->server_path ?
1070 				     fsc->mount_options->server_path + 1 : "";
1071 
1072 		err = __ceph_open_session(fsc->client, started);
1073 		if (err < 0)
1074 			goto out;
1075 
1076 		/* setup fscache */
1077 		if (fsc->mount_options->flags & CEPH_MOUNT_OPT_FSCACHE) {
1078 			err = ceph_fscache_register_fs(fsc, fc);
1079 			if (err < 0)
1080 				goto out;
1081 		}
1082 
1083 		dout("mount opening path '%s'\n", path);
1084 
1085 		ceph_fs_debugfs_init(fsc);
1086 
1087 		root = open_root_dentry(fsc, path, started);
1088 		if (IS_ERR(root)) {
1089 			err = PTR_ERR(root);
1090 			goto out;
1091 		}
1092 		fsc->sb->s_root = dget(root);
1093 	} else {
1094 		root = dget(fsc->sb->s_root);
1095 	}
1096 
1097 	fsc->mount_state = CEPH_MOUNT_MOUNTED;
1098 	dout("mount success\n");
1099 	mutex_unlock(&fsc->client->mount_mutex);
1100 	return root;
1101 
1102 out:
1103 	mutex_unlock(&fsc->client->mount_mutex);
1104 	return ERR_PTR(err);
1105 }
1106 
1107 static int ceph_set_super(struct super_block *s, struct fs_context *fc)
1108 {
1109 	struct ceph_fs_client *fsc = s->s_fs_info;
1110 	int ret;
1111 
1112 	dout("set_super %p\n", s);
1113 
1114 	s->s_maxbytes = MAX_LFS_FILESIZE;
1115 
1116 	s->s_xattr = ceph_xattr_handlers;
1117 	fsc->sb = s;
1118 	fsc->max_file_size = 1ULL << 40; /* temp value until we get mdsmap */
1119 
1120 	s->s_op = &ceph_super_ops;
1121 	s->s_d_op = &ceph_dentry_ops;
1122 	s->s_export_op = &ceph_export_ops;
1123 
1124 	s->s_time_gran = 1;
1125 	s->s_time_min = 0;
1126 	s->s_time_max = U32_MAX;
1127 	s->s_flags |= SB_NODIRATIME | SB_NOATIME;
1128 
1129 	ret = set_anon_super_fc(s, fc);
1130 	if (ret != 0)
1131 		fsc->sb = NULL;
1132 	return ret;
1133 }
1134 
1135 /*
1136  * share superblock if same fs AND options
1137  */
1138 static int ceph_compare_super(struct super_block *sb, struct fs_context *fc)
1139 {
1140 	struct ceph_fs_client *new = fc->s_fs_info;
1141 	struct ceph_mount_options *fsopt = new->mount_options;
1142 	struct ceph_options *opt = new->client->options;
1143 	struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
1144 
1145 	dout("ceph_compare_super %p\n", sb);
1146 
1147 	if (compare_mount_options(fsopt, opt, fsc)) {
1148 		dout("monitor(s)/mount options don't match\n");
1149 		return 0;
1150 	}
1151 	if ((opt->flags & CEPH_OPT_FSID) &&
1152 	    ceph_fsid_compare(&opt->fsid, &fsc->client->fsid)) {
1153 		dout("fsid doesn't match\n");
1154 		return 0;
1155 	}
1156 	if (fc->sb_flags != (sb->s_flags & ~SB_BORN)) {
1157 		dout("flags differ\n");
1158 		return 0;
1159 	}
1160 
1161 	if (fsc->blocklisted && !ceph_test_mount_opt(fsc, CLEANRECOVER)) {
1162 		dout("client is blocklisted (and CLEANRECOVER is not set)\n");
1163 		return 0;
1164 	}
1165 
1166 	if (fsc->mount_state == CEPH_MOUNT_SHUTDOWN) {
1167 		dout("client has been forcibly unmounted\n");
1168 		return 0;
1169 	}
1170 
1171 	return 1;
1172 }
1173 
1174 /*
1175  * construct our own bdi so we can control readahead, etc.
1176  */
1177 static atomic_long_t bdi_seq = ATOMIC_LONG_INIT(0);
1178 
1179 static int ceph_setup_bdi(struct super_block *sb, struct ceph_fs_client *fsc)
1180 {
1181 	int err;
1182 
1183 	err = super_setup_bdi_name(sb, "ceph-%ld",
1184 				   atomic_long_inc_return(&bdi_seq));
1185 	if (err)
1186 		return err;
1187 
1188 	/* set ra_pages based on rasize mount option? */
1189 	sb->s_bdi->ra_pages = fsc->mount_options->rasize >> PAGE_SHIFT;
1190 
1191 	/* set io_pages based on max osd read size */
1192 	sb->s_bdi->io_pages = fsc->mount_options->rsize >> PAGE_SHIFT;
1193 
1194 	return 0;
1195 }
1196 
1197 static int ceph_get_tree(struct fs_context *fc)
1198 {
1199 	struct ceph_parse_opts_ctx *pctx = fc->fs_private;
1200 	struct ceph_mount_options *fsopt = pctx->opts;
1201 	struct super_block *sb;
1202 	struct ceph_fs_client *fsc;
1203 	struct dentry *res;
1204 	int (*compare_super)(struct super_block *, struct fs_context *) =
1205 		ceph_compare_super;
1206 	int err;
1207 
1208 	dout("ceph_get_tree\n");
1209 
1210 	if (!fc->source)
1211 		return invalfc(fc, "No source");
1212 	if (fsopt->new_dev_syntax && !fsopt->mon_addr)
1213 		return invalfc(fc, "No monitor address");
1214 
1215 	/* create client (which we may/may not use) */
1216 	fsc = create_fs_client(pctx->opts, pctx->copts);
1217 	pctx->opts = NULL;
1218 	pctx->copts = NULL;
1219 	if (IS_ERR(fsc)) {
1220 		err = PTR_ERR(fsc);
1221 		goto out_final;
1222 	}
1223 
1224 	err = ceph_mdsc_init(fsc);
1225 	if (err < 0)
1226 		goto out;
1227 
1228 	if (ceph_test_opt(fsc->client, NOSHARE))
1229 		compare_super = NULL;
1230 
1231 	fc->s_fs_info = fsc;
1232 	sb = sget_fc(fc, compare_super, ceph_set_super);
1233 	fc->s_fs_info = NULL;
1234 	if (IS_ERR(sb)) {
1235 		err = PTR_ERR(sb);
1236 		goto out;
1237 	}
1238 
1239 	if (ceph_sb_to_client(sb) != fsc) {
1240 		destroy_fs_client(fsc);
1241 		fsc = ceph_sb_to_client(sb);
1242 		dout("get_sb got existing client %p\n", fsc);
1243 	} else {
1244 		dout("get_sb using new client %p\n", fsc);
1245 		err = ceph_setup_bdi(sb, fsc);
1246 		if (err < 0)
1247 			goto out_splat;
1248 	}
1249 
1250 	res = ceph_real_mount(fsc, fc);
1251 	if (IS_ERR(res)) {
1252 		err = PTR_ERR(res);
1253 		goto out_splat;
1254 	}
1255 	dout("root %p inode %p ino %llx.%llx\n", res,
1256 	     d_inode(res), ceph_vinop(d_inode(res)));
1257 	fc->root = fsc->sb->s_root;
1258 	return 0;
1259 
1260 out_splat:
1261 	if (!ceph_mdsmap_is_cluster_available(fsc->mdsc->mdsmap)) {
1262 		pr_info("No mds server is up or the cluster is laggy\n");
1263 		err = -EHOSTUNREACH;
1264 	}
1265 
1266 	ceph_mdsc_close_sessions(fsc->mdsc);
1267 	deactivate_locked_super(sb);
1268 	goto out_final;
1269 
1270 out:
1271 	destroy_fs_client(fsc);
1272 out_final:
1273 	dout("ceph_get_tree fail %d\n", err);
1274 	return err;
1275 }
1276 
1277 static void ceph_free_fc(struct fs_context *fc)
1278 {
1279 	struct ceph_parse_opts_ctx *pctx = fc->fs_private;
1280 
1281 	if (pctx) {
1282 		destroy_mount_options(pctx->opts);
1283 		ceph_destroy_options(pctx->copts);
1284 		kfree(pctx);
1285 	}
1286 }
1287 
1288 static int ceph_reconfigure_fc(struct fs_context *fc)
1289 {
1290 	struct ceph_parse_opts_ctx *pctx = fc->fs_private;
1291 	struct ceph_mount_options *fsopt = pctx->opts;
1292 	struct ceph_fs_client *fsc = ceph_sb_to_client(fc->root->d_sb);
1293 
1294 	if (fsopt->flags & CEPH_MOUNT_OPT_ASYNC_DIROPS)
1295 		ceph_set_mount_opt(fsc, ASYNC_DIROPS);
1296 	else
1297 		ceph_clear_mount_opt(fsc, ASYNC_DIROPS);
1298 
1299 	if (strcmp_null(fsc->mount_options->mon_addr, fsopt->mon_addr)) {
1300 		kfree(fsc->mount_options->mon_addr);
1301 		fsc->mount_options->mon_addr = fsopt->mon_addr;
1302 		fsopt->mon_addr = NULL;
1303 		pr_notice("ceph: monitor addresses recorded, but not used for reconnection");
1304 	}
1305 
1306 	sync_filesystem(fc->root->d_sb);
1307 	return 0;
1308 }
1309 
1310 static const struct fs_context_operations ceph_context_ops = {
1311 	.free		= ceph_free_fc,
1312 	.parse_param	= ceph_parse_mount_param,
1313 	.get_tree	= ceph_get_tree,
1314 	.reconfigure	= ceph_reconfigure_fc,
1315 };
1316 
1317 /*
1318  * Set up the filesystem mount context.
1319  */
1320 static int ceph_init_fs_context(struct fs_context *fc)
1321 {
1322 	struct ceph_parse_opts_ctx *pctx;
1323 	struct ceph_mount_options *fsopt;
1324 
1325 	pctx = kzalloc(sizeof(*pctx), GFP_KERNEL);
1326 	if (!pctx)
1327 		return -ENOMEM;
1328 
1329 	pctx->copts = ceph_alloc_options();
1330 	if (!pctx->copts)
1331 		goto nomem;
1332 
1333 	pctx->opts = kzalloc(sizeof(*pctx->opts), GFP_KERNEL);
1334 	if (!pctx->opts)
1335 		goto nomem;
1336 
1337 	fsopt = pctx->opts;
1338 	fsopt->flags = CEPH_MOUNT_OPT_DEFAULT;
1339 
1340 	fsopt->wsize = CEPH_MAX_WRITE_SIZE;
1341 	fsopt->rsize = CEPH_MAX_READ_SIZE;
1342 	fsopt->rasize = CEPH_RASIZE_DEFAULT;
1343 	fsopt->snapdir_name = kstrdup(CEPH_SNAPDIRNAME_DEFAULT, GFP_KERNEL);
1344 	if (!fsopt->snapdir_name)
1345 		goto nomem;
1346 
1347 	fsopt->caps_wanted_delay_min = CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT;
1348 	fsopt->caps_wanted_delay_max = CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT;
1349 	fsopt->max_readdir = CEPH_MAX_READDIR_DEFAULT;
1350 	fsopt->max_readdir_bytes = CEPH_MAX_READDIR_BYTES_DEFAULT;
1351 	fsopt->congestion_kb = default_congestion_kb();
1352 
1353 #ifdef CONFIG_CEPH_FS_POSIX_ACL
1354 	fc->sb_flags |= SB_POSIXACL;
1355 #endif
1356 
1357 	fc->fs_private = pctx;
1358 	fc->ops = &ceph_context_ops;
1359 	return 0;
1360 
1361 nomem:
1362 	destroy_mount_options(pctx->opts);
1363 	ceph_destroy_options(pctx->copts);
1364 	kfree(pctx);
1365 	return -ENOMEM;
1366 }
1367 
1368 static void ceph_kill_sb(struct super_block *s)
1369 {
1370 	struct ceph_fs_client *fsc = ceph_sb_to_client(s);
1371 
1372 	dout("kill_sb %p\n", s);
1373 
1374 	ceph_mdsc_pre_umount(fsc->mdsc);
1375 	flush_fs_workqueues(fsc);
1376 
1377 	kill_anon_super(s);
1378 
1379 	fsc->client->extra_mon_dispatch = NULL;
1380 	ceph_fs_debugfs_cleanup(fsc);
1381 
1382 	ceph_fscache_unregister_fs(fsc);
1383 
1384 	destroy_fs_client(fsc);
1385 }
1386 
1387 static struct file_system_type ceph_fs_type = {
1388 	.owner		= THIS_MODULE,
1389 	.name		= "ceph",
1390 	.init_fs_context = ceph_init_fs_context,
1391 	.kill_sb	= ceph_kill_sb,
1392 	.fs_flags	= FS_RENAME_DOES_D_MOVE,
1393 };
1394 MODULE_ALIAS_FS("ceph");
1395 
1396 int ceph_force_reconnect(struct super_block *sb)
1397 {
1398 	struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
1399 	int err = 0;
1400 
1401 	fsc->mount_state = CEPH_MOUNT_RECOVER;
1402 	__ceph_umount_begin(fsc);
1403 
1404 	/* Make sure all page caches get invalidated.
1405 	 * see remove_session_caps_cb() */
1406 	flush_workqueue(fsc->inode_wq);
1407 
1408 	/* In case that we were blocklisted. This also reset
1409 	 * all mon/osd connections */
1410 	ceph_reset_client_addr(fsc->client);
1411 
1412 	ceph_osdc_clear_abort_err(&fsc->client->osdc);
1413 
1414 	fsc->blocklisted = false;
1415 	fsc->mount_state = CEPH_MOUNT_MOUNTED;
1416 
1417 	if (sb->s_root) {
1418 		err = __ceph_do_getattr(d_inode(sb->s_root), NULL,
1419 					CEPH_STAT_CAP_INODE, true);
1420 	}
1421 	return err;
1422 }
1423 
1424 static int __init init_ceph(void)
1425 {
1426 	int ret = init_caches();
1427 	if (ret)
1428 		goto out;
1429 
1430 	ceph_flock_init();
1431 	ret = register_filesystem(&ceph_fs_type);
1432 	if (ret)
1433 		goto out_caches;
1434 
1435 	pr_info("loaded (mds proto %d)\n", CEPH_MDSC_PROTOCOL);
1436 
1437 	return 0;
1438 
1439 out_caches:
1440 	destroy_caches();
1441 out:
1442 	return ret;
1443 }
1444 
1445 static void __exit exit_ceph(void)
1446 {
1447 	dout("exit_ceph\n");
1448 	unregister_filesystem(&ceph_fs_type);
1449 	destroy_caches();
1450 }
1451 
1452 static int param_set_metrics(const char *val, const struct kernel_param *kp)
1453 {
1454 	struct ceph_fs_client *fsc;
1455 	int ret;
1456 
1457 	ret = param_set_bool(val, kp);
1458 	if (ret) {
1459 		pr_err("Failed to parse sending metrics switch value '%s'\n",
1460 		       val);
1461 		return ret;
1462 	} else if (!disable_send_metrics) {
1463 		// wake up all the mds clients
1464 		spin_lock(&ceph_fsc_lock);
1465 		list_for_each_entry(fsc, &ceph_fsc_list, metric_wakeup) {
1466 			metric_schedule_delayed(&fsc->mdsc->metric);
1467 		}
1468 		spin_unlock(&ceph_fsc_lock);
1469 	}
1470 
1471 	return 0;
1472 }
1473 
1474 static const struct kernel_param_ops param_ops_metrics = {
1475 	.set = param_set_metrics,
1476 	.get = param_get_bool,
1477 };
1478 
1479 bool disable_send_metrics = false;
1480 module_param_cb(disable_send_metrics, &param_ops_metrics, &disable_send_metrics, 0644);
1481 MODULE_PARM_DESC(disable_send_metrics, "Enable sending perf metrics to ceph cluster (default: on)");
1482 
1483 /* for both v1 and v2 syntax */
1484 static bool mount_support = true;
1485 static const struct kernel_param_ops param_ops_mount_syntax = {
1486 	.get = param_get_bool,
1487 };
1488 module_param_cb(mount_syntax_v1, &param_ops_mount_syntax, &mount_support, 0444);
1489 module_param_cb(mount_syntax_v2, &param_ops_mount_syntax, &mount_support, 0444);
1490 
1491 module_init(init_ceph);
1492 module_exit(exit_ceph);
1493 
1494 MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
1495 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
1496 MODULE_AUTHOR("Patience Warnick <patience@newdream.net>");
1497 MODULE_DESCRIPTION("Ceph filesystem for Linux");
1498 MODULE_LICENSE("GPL");
1499