xref: /openbmc/linux/fs/ceph/super.c (revision 242cdad8)
1 
2 #include <linux/ceph/ceph_debug.h>
3 
4 #include <linux/backing-dev.h>
5 #include <linux/ctype.h>
6 #include <linux/fs.h>
7 #include <linux/inet.h>
8 #include <linux/in6.h>
9 #include <linux/module.h>
10 #include <linux/mount.h>
11 #include <linux/parser.h>
12 #include <linux/sched.h>
13 #include <linux/seq_file.h>
14 #include <linux/slab.h>
15 #include <linux/statfs.h>
16 #include <linux/string.h>
17 
18 #include "super.h"
19 #include "mds_client.h"
20 #include "cache.h"
21 
22 #include <linux/ceph/ceph_features.h>
23 #include <linux/ceph/decode.h>
24 #include <linux/ceph/mon_client.h>
25 #include <linux/ceph/auth.h>
26 #include <linux/ceph/debugfs.h>
27 
28 /*
29  * Ceph superblock operations
30  *
31  * Handle the basics of mounting, unmounting.
32  */
33 
34 /*
35  * super ops
36  */
37 static void ceph_put_super(struct super_block *s)
38 {
39 	struct ceph_fs_client *fsc = ceph_sb_to_client(s);
40 
41 	dout("put_super\n");
42 	ceph_mdsc_close_sessions(fsc->mdsc);
43 }
44 
45 static int ceph_statfs(struct dentry *dentry, struct kstatfs *buf)
46 {
47 	struct ceph_fs_client *fsc = ceph_inode_to_client(d_inode(dentry));
48 	struct ceph_mon_client *monc = &fsc->client->monc;
49 	struct ceph_statfs st;
50 	u64 fsid;
51 	int err;
52 	u64 data_pool;
53 
54 	if (fsc->mdsc->mdsmap->m_num_data_pg_pools == 1) {
55 		data_pool = fsc->mdsc->mdsmap->m_data_pg_pools[0];
56 	} else {
57 		data_pool = CEPH_NOPOOL;
58 	}
59 
60 	dout("statfs\n");
61 	err = ceph_monc_do_statfs(monc, data_pool, &st);
62 	if (err < 0)
63 		return err;
64 
65 	/* fill in kstatfs */
66 	buf->f_type = CEPH_SUPER_MAGIC;  /* ?? */
67 
68 	/*
69 	 * express utilization in terms of large blocks to avoid
70 	 * overflow on 32-bit machines.
71 	 *
72 	 * NOTE: for the time being, we make bsize == frsize to humor
73 	 * not-yet-ancient versions of glibc that are broken.
74 	 * Someday, we will probably want to report a real block
75 	 * size...  whatever that may mean for a network file system!
76 	 */
77 	buf->f_bsize = 1 << CEPH_BLOCK_SHIFT;
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 	buf->f_files = le64_to_cpu(st.num_objects);
93 	buf->f_ffree = -1;
94 	buf->f_namelen = NAME_MAX;
95 
96 	/* Must convert the fsid, for consistent values across arches */
97 	mutex_lock(&monc->mutex);
98 	fsid = le64_to_cpu(*(__le64 *)(&monc->monmap->fsid)) ^
99 	       le64_to_cpu(*((__le64 *)&monc->monmap->fsid + 1));
100 	mutex_unlock(&monc->mutex);
101 
102 	buf->f_fsid.val[0] = fsid & 0xffffffff;
103 	buf->f_fsid.val[1] = fsid >> 32;
104 
105 	return 0;
106 }
107 
108 
109 static int ceph_sync_fs(struct super_block *sb, int wait)
110 {
111 	struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
112 
113 	if (!wait) {
114 		dout("sync_fs (non-blocking)\n");
115 		ceph_flush_dirty_caps(fsc->mdsc);
116 		dout("sync_fs (non-blocking) done\n");
117 		return 0;
118 	}
119 
120 	dout("sync_fs (blocking)\n");
121 	ceph_osdc_sync(&fsc->client->osdc);
122 	ceph_mdsc_sync(fsc->mdsc);
123 	dout("sync_fs (blocking) done\n");
124 	return 0;
125 }
126 
127 /*
128  * mount options
129  */
130 enum {
131 	Opt_wsize,
132 	Opt_rsize,
133 	Opt_rasize,
134 	Opt_caps_wanted_delay_min,
135 	Opt_caps_wanted_delay_max,
136 	Opt_readdir_max_entries,
137 	Opt_readdir_max_bytes,
138 	Opt_congestion_kb,
139 	Opt_last_int,
140 	/* int args above */
141 	Opt_snapdirname,
142 	Opt_mds_namespace,
143 	Opt_fscache_uniq,
144 	Opt_last_string,
145 	/* string args above */
146 	Opt_dirstat,
147 	Opt_nodirstat,
148 	Opt_rbytes,
149 	Opt_norbytes,
150 	Opt_asyncreaddir,
151 	Opt_noasyncreaddir,
152 	Opt_dcache,
153 	Opt_nodcache,
154 	Opt_ino32,
155 	Opt_noino32,
156 	Opt_fscache,
157 	Opt_nofscache,
158 	Opt_poolperm,
159 	Opt_nopoolperm,
160 	Opt_require_active_mds,
161 	Opt_norequire_active_mds,
162 #ifdef CONFIG_CEPH_FS_POSIX_ACL
163 	Opt_acl,
164 #endif
165 	Opt_noacl,
166 	Opt_quotadf,
167 	Opt_noquotadf,
168 };
169 
170 static match_table_t fsopt_tokens = {
171 	{Opt_wsize, "wsize=%d"},
172 	{Opt_rsize, "rsize=%d"},
173 	{Opt_rasize, "rasize=%d"},
174 	{Opt_caps_wanted_delay_min, "caps_wanted_delay_min=%d"},
175 	{Opt_caps_wanted_delay_max, "caps_wanted_delay_max=%d"},
176 	{Opt_readdir_max_entries, "readdir_max_entries=%d"},
177 	{Opt_readdir_max_bytes, "readdir_max_bytes=%d"},
178 	{Opt_congestion_kb, "write_congestion_kb=%d"},
179 	/* int args above */
180 	{Opt_snapdirname, "snapdirname=%s"},
181 	{Opt_mds_namespace, "mds_namespace=%s"},
182 	{Opt_fscache_uniq, "fsc=%s"},
183 	/* string args above */
184 	{Opt_dirstat, "dirstat"},
185 	{Opt_nodirstat, "nodirstat"},
186 	{Opt_rbytes, "rbytes"},
187 	{Opt_norbytes, "norbytes"},
188 	{Opt_asyncreaddir, "asyncreaddir"},
189 	{Opt_noasyncreaddir, "noasyncreaddir"},
190 	{Opt_dcache, "dcache"},
191 	{Opt_nodcache, "nodcache"},
192 	{Opt_ino32, "ino32"},
193 	{Opt_noino32, "noino32"},
194 	{Opt_fscache, "fsc"},
195 	{Opt_nofscache, "nofsc"},
196 	{Opt_poolperm, "poolperm"},
197 	{Opt_nopoolperm, "nopoolperm"},
198 	{Opt_require_active_mds, "require_active_mds"},
199 	{Opt_norequire_active_mds, "norequire_active_mds"},
200 #ifdef CONFIG_CEPH_FS_POSIX_ACL
201 	{Opt_acl, "acl"},
202 #endif
203 	{Opt_noacl, "noacl"},
204 	{Opt_quotadf, "quotadf"},
205 	{Opt_noquotadf, "noquotadf"},
206 	{-1, NULL}
207 };
208 
209 static int parse_fsopt_token(char *c, void *private)
210 {
211 	struct ceph_mount_options *fsopt = private;
212 	substring_t argstr[MAX_OPT_ARGS];
213 	int token, intval, ret;
214 
215 	token = match_token((char *)c, fsopt_tokens, argstr);
216 	if (token < 0)
217 		return -EINVAL;
218 
219 	if (token < Opt_last_int) {
220 		ret = match_int(&argstr[0], &intval);
221 		if (ret < 0) {
222 			pr_err("bad option arg (not int) at '%s'\n", c);
223 			return ret;
224 		}
225 		dout("got int token %d val %d\n", token, intval);
226 	} else if (token > Opt_last_int && token < Opt_last_string) {
227 		dout("got string token %d val %s\n", token,
228 		     argstr[0].from);
229 	} else {
230 		dout("got token %d\n", token);
231 	}
232 
233 	switch (token) {
234 	case Opt_snapdirname:
235 		kfree(fsopt->snapdir_name);
236 		fsopt->snapdir_name = kstrndup(argstr[0].from,
237 					       argstr[0].to-argstr[0].from,
238 					       GFP_KERNEL);
239 		if (!fsopt->snapdir_name)
240 			return -ENOMEM;
241 		break;
242 	case Opt_mds_namespace:
243 		kfree(fsopt->mds_namespace);
244 		fsopt->mds_namespace = kstrndup(argstr[0].from,
245 						argstr[0].to-argstr[0].from,
246 						GFP_KERNEL);
247 		if (!fsopt->mds_namespace)
248 			return -ENOMEM;
249 		break;
250 	case Opt_fscache_uniq:
251 		kfree(fsopt->fscache_uniq);
252 		fsopt->fscache_uniq = kstrndup(argstr[0].from,
253 					       argstr[0].to-argstr[0].from,
254 					       GFP_KERNEL);
255 		if (!fsopt->fscache_uniq)
256 			return -ENOMEM;
257 		fsopt->flags |= CEPH_MOUNT_OPT_FSCACHE;
258 		break;
259 		/* misc */
260 	case Opt_wsize:
261 		if (intval < (int)PAGE_SIZE || intval > CEPH_MAX_WRITE_SIZE)
262 			return -EINVAL;
263 		fsopt->wsize = ALIGN(intval, PAGE_SIZE);
264 		break;
265 	case Opt_rsize:
266 		if (intval < (int)PAGE_SIZE || intval > CEPH_MAX_READ_SIZE)
267 			return -EINVAL;
268 		fsopt->rsize = ALIGN(intval, PAGE_SIZE);
269 		break;
270 	case Opt_rasize:
271 		if (intval < 0)
272 			return -EINVAL;
273 		fsopt->rasize = ALIGN(intval, PAGE_SIZE);
274 		break;
275 	case Opt_caps_wanted_delay_min:
276 		if (intval < 1)
277 			return -EINVAL;
278 		fsopt->caps_wanted_delay_min = intval;
279 		break;
280 	case Opt_caps_wanted_delay_max:
281 		if (intval < 1)
282 			return -EINVAL;
283 		fsopt->caps_wanted_delay_max = intval;
284 		break;
285 	case Opt_readdir_max_entries:
286 		if (intval < 1)
287 			return -EINVAL;
288 		fsopt->max_readdir = intval;
289 		break;
290 	case Opt_readdir_max_bytes:
291 		if (intval < (int)PAGE_SIZE && intval != 0)
292 			return -EINVAL;
293 		fsopt->max_readdir_bytes = intval;
294 		break;
295 	case Opt_congestion_kb:
296 		if (intval < 1024) /* at least 1M */
297 			return -EINVAL;
298 		fsopt->congestion_kb = intval;
299 		break;
300 	case Opt_dirstat:
301 		fsopt->flags |= CEPH_MOUNT_OPT_DIRSTAT;
302 		break;
303 	case Opt_nodirstat:
304 		fsopt->flags &= ~CEPH_MOUNT_OPT_DIRSTAT;
305 		break;
306 	case Opt_rbytes:
307 		fsopt->flags |= CEPH_MOUNT_OPT_RBYTES;
308 		break;
309 	case Opt_norbytes:
310 		fsopt->flags &= ~CEPH_MOUNT_OPT_RBYTES;
311 		break;
312 	case Opt_asyncreaddir:
313 		fsopt->flags &= ~CEPH_MOUNT_OPT_NOASYNCREADDIR;
314 		break;
315 	case Opt_noasyncreaddir:
316 		fsopt->flags |= CEPH_MOUNT_OPT_NOASYNCREADDIR;
317 		break;
318 	case Opt_dcache:
319 		fsopt->flags |= CEPH_MOUNT_OPT_DCACHE;
320 		break;
321 	case Opt_nodcache:
322 		fsopt->flags &= ~CEPH_MOUNT_OPT_DCACHE;
323 		break;
324 	case Opt_ino32:
325 		fsopt->flags |= CEPH_MOUNT_OPT_INO32;
326 		break;
327 	case Opt_noino32:
328 		fsopt->flags &= ~CEPH_MOUNT_OPT_INO32;
329 		break;
330 	case Opt_fscache:
331 		fsopt->flags |= CEPH_MOUNT_OPT_FSCACHE;
332 		kfree(fsopt->fscache_uniq);
333 		fsopt->fscache_uniq = NULL;
334 		break;
335 	case Opt_nofscache:
336 		fsopt->flags &= ~CEPH_MOUNT_OPT_FSCACHE;
337 		kfree(fsopt->fscache_uniq);
338 		fsopt->fscache_uniq = NULL;
339 		break;
340 	case Opt_poolperm:
341 		fsopt->flags &= ~CEPH_MOUNT_OPT_NOPOOLPERM;
342 		break;
343 	case Opt_nopoolperm:
344 		fsopt->flags |= CEPH_MOUNT_OPT_NOPOOLPERM;
345 		break;
346 	case Opt_require_active_mds:
347 		fsopt->flags &= ~CEPH_MOUNT_OPT_MOUNTWAIT;
348 		break;
349 	case Opt_norequire_active_mds:
350 		fsopt->flags |= CEPH_MOUNT_OPT_MOUNTWAIT;
351 		break;
352 	case Opt_quotadf:
353 		fsopt->flags &= ~CEPH_MOUNT_OPT_NOQUOTADF;
354 		break;
355 	case Opt_noquotadf:
356 		fsopt->flags |= CEPH_MOUNT_OPT_NOQUOTADF;
357 		break;
358 #ifdef CONFIG_CEPH_FS_POSIX_ACL
359 	case Opt_acl:
360 		fsopt->sb_flags |= SB_POSIXACL;
361 		break;
362 #endif
363 	case Opt_noacl:
364 		fsopt->sb_flags &= ~SB_POSIXACL;
365 		break;
366 	default:
367 		BUG_ON(token);
368 	}
369 	return 0;
370 }
371 
372 static void destroy_mount_options(struct ceph_mount_options *args)
373 {
374 	dout("destroy_mount_options %p\n", args);
375 	kfree(args->snapdir_name);
376 	kfree(args->mds_namespace);
377 	kfree(args->server_path);
378 	kfree(args->fscache_uniq);
379 	kfree(args);
380 }
381 
382 static int strcmp_null(const char *s1, const char *s2)
383 {
384 	if (!s1 && !s2)
385 		return 0;
386 	if (s1 && !s2)
387 		return -1;
388 	if (!s1 && s2)
389 		return 1;
390 	return strcmp(s1, s2);
391 }
392 
393 static int compare_mount_options(struct ceph_mount_options *new_fsopt,
394 				 struct ceph_options *new_opt,
395 				 struct ceph_fs_client *fsc)
396 {
397 	struct ceph_mount_options *fsopt1 = new_fsopt;
398 	struct ceph_mount_options *fsopt2 = fsc->mount_options;
399 	int ofs = offsetof(struct ceph_mount_options, snapdir_name);
400 	int ret;
401 
402 	ret = memcmp(fsopt1, fsopt2, ofs);
403 	if (ret)
404 		return ret;
405 
406 	ret = strcmp_null(fsopt1->snapdir_name, fsopt2->snapdir_name);
407 	if (ret)
408 		return ret;
409 	ret = strcmp_null(fsopt1->mds_namespace, fsopt2->mds_namespace);
410 	if (ret)
411 		return ret;
412 	ret = strcmp_null(fsopt1->server_path, fsopt2->server_path);
413 	if (ret)
414 		return ret;
415 	ret = strcmp_null(fsopt1->fscache_uniq, fsopt2->fscache_uniq);
416 	if (ret)
417 		return ret;
418 
419 	return ceph_compare_options(new_opt, fsc->client);
420 }
421 
422 static int parse_mount_options(struct ceph_mount_options **pfsopt,
423 			       struct ceph_options **popt,
424 			       int flags, char *options,
425 			       const char *dev_name)
426 {
427 	struct ceph_mount_options *fsopt;
428 	const char *dev_name_end;
429 	int err;
430 
431 	if (!dev_name || !*dev_name)
432 		return -EINVAL;
433 
434 	fsopt = kzalloc(sizeof(*fsopt), GFP_KERNEL);
435 	if (!fsopt)
436 		return -ENOMEM;
437 
438 	dout("parse_mount_options %p, dev_name '%s'\n", fsopt, dev_name);
439 
440 	fsopt->sb_flags = flags;
441 	fsopt->flags = CEPH_MOUNT_OPT_DEFAULT;
442 
443 	fsopt->wsize = CEPH_MAX_WRITE_SIZE;
444 	fsopt->rsize = CEPH_MAX_READ_SIZE;
445 	fsopt->rasize = CEPH_RASIZE_DEFAULT;
446 	fsopt->snapdir_name = kstrdup(CEPH_SNAPDIRNAME_DEFAULT, GFP_KERNEL);
447 	if (!fsopt->snapdir_name) {
448 		err = -ENOMEM;
449 		goto out;
450 	}
451 
452 	fsopt->caps_wanted_delay_min = CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT;
453 	fsopt->caps_wanted_delay_max = CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT;
454 	fsopt->max_readdir = CEPH_MAX_READDIR_DEFAULT;
455 	fsopt->max_readdir_bytes = CEPH_MAX_READDIR_BYTES_DEFAULT;
456 	fsopt->congestion_kb = default_congestion_kb();
457 
458 	/*
459 	 * Distinguish the server list from the path in "dev_name".
460 	 * Internally we do not include the leading '/' in the path.
461 	 *
462 	 * "dev_name" will look like:
463 	 *     <server_spec>[,<server_spec>...]:[<path>]
464 	 * where
465 	 *     <server_spec> is <ip>[:<port>]
466 	 *     <path> is optional, but if present must begin with '/'
467 	 */
468 	dev_name_end = strchr(dev_name, '/');
469 	if (dev_name_end) {
470 		if (strlen(dev_name_end) > 1) {
471 			fsopt->server_path = kstrdup(dev_name_end, GFP_KERNEL);
472 			if (!fsopt->server_path) {
473 				err = -ENOMEM;
474 				goto out;
475 			}
476 		}
477 	} else {
478 		dev_name_end = dev_name + strlen(dev_name);
479 	}
480 	err = -EINVAL;
481 	dev_name_end--;		/* back up to ':' separator */
482 	if (dev_name_end < dev_name || *dev_name_end != ':') {
483 		pr_err("device name is missing path (no : separator in %s)\n",
484 				dev_name);
485 		goto out;
486 	}
487 	dout("device name '%.*s'\n", (int)(dev_name_end - dev_name), dev_name);
488 	if (fsopt->server_path)
489 		dout("server path '%s'\n", fsopt->server_path);
490 
491 	*popt = ceph_parse_options(options, dev_name, dev_name_end,
492 				 parse_fsopt_token, (void *)fsopt);
493 	if (IS_ERR(*popt)) {
494 		err = PTR_ERR(*popt);
495 		goto out;
496 	}
497 
498 	/* success */
499 	*pfsopt = fsopt;
500 	return 0;
501 
502 out:
503 	destroy_mount_options(fsopt);
504 	return err;
505 }
506 
507 /**
508  * ceph_show_options - Show mount options in /proc/mounts
509  * @m: seq_file to write to
510  * @root: root of that (sub)tree
511  */
512 static int ceph_show_options(struct seq_file *m, struct dentry *root)
513 {
514 	struct ceph_fs_client *fsc = ceph_sb_to_client(root->d_sb);
515 	struct ceph_mount_options *fsopt = fsc->mount_options;
516 	size_t pos;
517 	int ret;
518 
519 	/* a comma between MNT/MS and client options */
520 	seq_putc(m, ',');
521 	pos = m->count;
522 
523 	ret = ceph_print_client_options(m, fsc->client);
524 	if (ret)
525 		return ret;
526 
527 	/* retract our comma if no client options */
528 	if (m->count == pos)
529 		m->count--;
530 
531 	if (fsopt->flags & CEPH_MOUNT_OPT_DIRSTAT)
532 		seq_puts(m, ",dirstat");
533 	if ((fsopt->flags & CEPH_MOUNT_OPT_RBYTES))
534 		seq_puts(m, ",rbytes");
535 	if (fsopt->flags & CEPH_MOUNT_OPT_NOASYNCREADDIR)
536 		seq_puts(m, ",noasyncreaddir");
537 	if ((fsopt->flags & CEPH_MOUNT_OPT_DCACHE) == 0)
538 		seq_puts(m, ",nodcache");
539 	if (fsopt->flags & CEPH_MOUNT_OPT_INO32)
540 		seq_puts(m, ",ino32");
541 	if (fsopt->flags & CEPH_MOUNT_OPT_FSCACHE) {
542 		seq_show_option(m, "fsc", fsopt->fscache_uniq);
543 	}
544 	if (fsopt->flags & CEPH_MOUNT_OPT_NOPOOLPERM)
545 		seq_puts(m, ",nopoolperm");
546 	if (fsopt->flags & CEPH_MOUNT_OPT_NOQUOTADF)
547 		seq_puts(m, ",noquotadf");
548 
549 #ifdef CONFIG_CEPH_FS_POSIX_ACL
550 	if (fsopt->sb_flags & SB_POSIXACL)
551 		seq_puts(m, ",acl");
552 	else
553 		seq_puts(m, ",noacl");
554 #endif
555 
556 	if (fsopt->mds_namespace)
557 		seq_show_option(m, "mds_namespace", fsopt->mds_namespace);
558 	if (fsopt->wsize != CEPH_MAX_WRITE_SIZE)
559 		seq_printf(m, ",wsize=%d", fsopt->wsize);
560 	if (fsopt->rsize != CEPH_MAX_READ_SIZE)
561 		seq_printf(m, ",rsize=%d", fsopt->rsize);
562 	if (fsopt->rasize != CEPH_RASIZE_DEFAULT)
563 		seq_printf(m, ",rasize=%d", fsopt->rasize);
564 	if (fsopt->congestion_kb != default_congestion_kb())
565 		seq_printf(m, ",write_congestion_kb=%d", fsopt->congestion_kb);
566 	if (fsopt->caps_wanted_delay_min != CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT)
567 		seq_printf(m, ",caps_wanted_delay_min=%d",
568 			 fsopt->caps_wanted_delay_min);
569 	if (fsopt->caps_wanted_delay_max != CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT)
570 		seq_printf(m, ",caps_wanted_delay_max=%d",
571 			   fsopt->caps_wanted_delay_max);
572 	if (fsopt->max_readdir != CEPH_MAX_READDIR_DEFAULT)
573 		seq_printf(m, ",readdir_max_entries=%d", fsopt->max_readdir);
574 	if (fsopt->max_readdir_bytes != CEPH_MAX_READDIR_BYTES_DEFAULT)
575 		seq_printf(m, ",readdir_max_bytes=%d", fsopt->max_readdir_bytes);
576 	if (strcmp(fsopt->snapdir_name, CEPH_SNAPDIRNAME_DEFAULT))
577 		seq_show_option(m, "snapdirname", fsopt->snapdir_name);
578 
579 	return 0;
580 }
581 
582 /*
583  * handle any mon messages the standard library doesn't understand.
584  * return error if we don't either.
585  */
586 static int extra_mon_dispatch(struct ceph_client *client, struct ceph_msg *msg)
587 {
588 	struct ceph_fs_client *fsc = client->private;
589 	int type = le16_to_cpu(msg->hdr.type);
590 
591 	switch (type) {
592 	case CEPH_MSG_MDS_MAP:
593 		ceph_mdsc_handle_mdsmap(fsc->mdsc, msg);
594 		return 0;
595 	case CEPH_MSG_FS_MAP_USER:
596 		ceph_mdsc_handle_fsmap(fsc->mdsc, msg);
597 		return 0;
598 	default:
599 		return -1;
600 	}
601 }
602 
603 /*
604  * create a new fs client
605  *
606  * Success or not, this function consumes @fsopt and @opt.
607  */
608 static struct ceph_fs_client *create_fs_client(struct ceph_mount_options *fsopt,
609 					struct ceph_options *opt)
610 {
611 	struct ceph_fs_client *fsc;
612 	int page_count;
613 	size_t size;
614 	int err;
615 
616 	fsc = kzalloc(sizeof(*fsc), GFP_KERNEL);
617 	if (!fsc) {
618 		err = -ENOMEM;
619 		goto fail;
620 	}
621 
622 	fsc->client = ceph_create_client(opt, fsc);
623 	if (IS_ERR(fsc->client)) {
624 		err = PTR_ERR(fsc->client);
625 		goto fail;
626 	}
627 	opt = NULL; /* fsc->client now owns this */
628 
629 	fsc->client->extra_mon_dispatch = extra_mon_dispatch;
630 	fsc->client->osdc.abort_on_full = true;
631 
632 	if (!fsopt->mds_namespace) {
633 		ceph_monc_want_map(&fsc->client->monc, CEPH_SUB_MDSMAP,
634 				   0, true);
635 	} else {
636 		ceph_monc_want_map(&fsc->client->monc, CEPH_SUB_FSMAP,
637 				   0, false);
638 	}
639 
640 	fsc->mount_options = fsopt;
641 
642 	fsc->sb = NULL;
643 	fsc->mount_state = CEPH_MOUNT_MOUNTING;
644 
645 	atomic_long_set(&fsc->writeback_count, 0);
646 
647 	err = -ENOMEM;
648 	/*
649 	 * The number of concurrent works can be high but they don't need
650 	 * to be processed in parallel, limit concurrency.
651 	 */
652 	fsc->wb_wq = alloc_workqueue("ceph-writeback", 0, 1);
653 	if (!fsc->wb_wq)
654 		goto fail_client;
655 	fsc->pg_inv_wq = alloc_workqueue("ceph-pg-invalid", 0, 1);
656 	if (!fsc->pg_inv_wq)
657 		goto fail_wb_wq;
658 	fsc->trunc_wq = alloc_workqueue("ceph-trunc", 0, 1);
659 	if (!fsc->trunc_wq)
660 		goto fail_pg_inv_wq;
661 
662 	/* set up mempools */
663 	err = -ENOMEM;
664 	page_count = fsc->mount_options->wsize >> PAGE_SHIFT;
665 	size = sizeof (struct page *) * (page_count ? page_count : 1);
666 	fsc->wb_pagevec_pool = mempool_create_kmalloc_pool(10, size);
667 	if (!fsc->wb_pagevec_pool)
668 		goto fail_trunc_wq;
669 
670 	/* caps */
671 	fsc->min_caps = fsopt->max_readdir;
672 
673 	return fsc;
674 
675 fail_trunc_wq:
676 	destroy_workqueue(fsc->trunc_wq);
677 fail_pg_inv_wq:
678 	destroy_workqueue(fsc->pg_inv_wq);
679 fail_wb_wq:
680 	destroy_workqueue(fsc->wb_wq);
681 fail_client:
682 	ceph_destroy_client(fsc->client);
683 fail:
684 	kfree(fsc);
685 	if (opt)
686 		ceph_destroy_options(opt);
687 	destroy_mount_options(fsopt);
688 	return ERR_PTR(err);
689 }
690 
691 static void flush_fs_workqueues(struct ceph_fs_client *fsc)
692 {
693 	flush_workqueue(fsc->wb_wq);
694 	flush_workqueue(fsc->pg_inv_wq);
695 	flush_workqueue(fsc->trunc_wq);
696 }
697 
698 static void destroy_fs_client(struct ceph_fs_client *fsc)
699 {
700 	dout("destroy_fs_client %p\n", fsc);
701 
702 	destroy_workqueue(fsc->wb_wq);
703 	destroy_workqueue(fsc->pg_inv_wq);
704 	destroy_workqueue(fsc->trunc_wq);
705 
706 	mempool_destroy(fsc->wb_pagevec_pool);
707 
708 	destroy_mount_options(fsc->mount_options);
709 
710 	ceph_destroy_client(fsc->client);
711 
712 	kfree(fsc);
713 	dout("destroy_fs_client %p done\n", fsc);
714 }
715 
716 /*
717  * caches
718  */
719 struct kmem_cache *ceph_inode_cachep;
720 struct kmem_cache *ceph_cap_cachep;
721 struct kmem_cache *ceph_cap_flush_cachep;
722 struct kmem_cache *ceph_dentry_cachep;
723 struct kmem_cache *ceph_file_cachep;
724 struct kmem_cache *ceph_dir_file_cachep;
725 
726 static void ceph_inode_init_once(void *foo)
727 {
728 	struct ceph_inode_info *ci = foo;
729 	inode_init_once(&ci->vfs_inode);
730 }
731 
732 static int __init init_caches(void)
733 {
734 	int error = -ENOMEM;
735 
736 	ceph_inode_cachep = kmem_cache_create("ceph_inode_info",
737 				      sizeof(struct ceph_inode_info),
738 				      __alignof__(struct ceph_inode_info),
739 				      SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
740 				      SLAB_ACCOUNT, ceph_inode_init_once);
741 	if (!ceph_inode_cachep)
742 		return -ENOMEM;
743 
744 	ceph_cap_cachep = KMEM_CACHE(ceph_cap, SLAB_MEM_SPREAD);
745 	if (!ceph_cap_cachep)
746 		goto bad_cap;
747 	ceph_cap_flush_cachep = KMEM_CACHE(ceph_cap_flush,
748 					   SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
749 	if (!ceph_cap_flush_cachep)
750 		goto bad_cap_flush;
751 
752 	ceph_dentry_cachep = KMEM_CACHE(ceph_dentry_info,
753 					SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
754 	if (!ceph_dentry_cachep)
755 		goto bad_dentry;
756 
757 	ceph_file_cachep = KMEM_CACHE(ceph_file_info, SLAB_MEM_SPREAD);
758 	if (!ceph_file_cachep)
759 		goto bad_file;
760 
761 	ceph_dir_file_cachep = KMEM_CACHE(ceph_dir_file_info, SLAB_MEM_SPREAD);
762 	if (!ceph_dir_file_cachep)
763 		goto bad_dir_file;
764 
765 	error = ceph_fscache_register();
766 	if (error)
767 		goto bad_fscache;
768 
769 	return 0;
770 
771 bad_fscache:
772 	kmem_cache_destroy(ceph_dir_file_cachep);
773 bad_dir_file:
774 	kmem_cache_destroy(ceph_file_cachep);
775 bad_file:
776 	kmem_cache_destroy(ceph_dentry_cachep);
777 bad_dentry:
778 	kmem_cache_destroy(ceph_cap_flush_cachep);
779 bad_cap_flush:
780 	kmem_cache_destroy(ceph_cap_cachep);
781 bad_cap:
782 	kmem_cache_destroy(ceph_inode_cachep);
783 	return error;
784 }
785 
786 static void destroy_caches(void)
787 {
788 	/*
789 	 * Make sure all delayed rcu free inodes are flushed before we
790 	 * destroy cache.
791 	 */
792 	rcu_barrier();
793 
794 	kmem_cache_destroy(ceph_inode_cachep);
795 	kmem_cache_destroy(ceph_cap_cachep);
796 	kmem_cache_destroy(ceph_cap_flush_cachep);
797 	kmem_cache_destroy(ceph_dentry_cachep);
798 	kmem_cache_destroy(ceph_file_cachep);
799 	kmem_cache_destroy(ceph_dir_file_cachep);
800 
801 	ceph_fscache_unregister();
802 }
803 
804 
805 /*
806  * ceph_umount_begin - initiate forced umount.  Tear down down the
807  * mount, skipping steps that may hang while waiting for server(s).
808  */
809 static void ceph_umount_begin(struct super_block *sb)
810 {
811 	struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
812 
813 	dout("ceph_umount_begin - starting forced umount\n");
814 	if (!fsc)
815 		return;
816 	fsc->mount_state = CEPH_MOUNT_SHUTDOWN;
817 	ceph_osdc_abort_requests(&fsc->client->osdc, -EIO);
818 	ceph_mdsc_force_umount(fsc->mdsc);
819 	return;
820 }
821 
822 static const struct super_operations ceph_super_ops = {
823 	.alloc_inode	= ceph_alloc_inode,
824 	.destroy_inode	= ceph_destroy_inode,
825 	.write_inode    = ceph_write_inode,
826 	.drop_inode	= ceph_drop_inode,
827 	.sync_fs        = ceph_sync_fs,
828 	.put_super	= ceph_put_super,
829 	.show_options   = ceph_show_options,
830 	.statfs		= ceph_statfs,
831 	.umount_begin   = ceph_umount_begin,
832 };
833 
834 /*
835  * Bootstrap mount by opening the root directory.  Note the mount
836  * @started time from caller, and time out if this takes too long.
837  */
838 static struct dentry *open_root_dentry(struct ceph_fs_client *fsc,
839 				       const char *path,
840 				       unsigned long started)
841 {
842 	struct ceph_mds_client *mdsc = fsc->mdsc;
843 	struct ceph_mds_request *req = NULL;
844 	int err;
845 	struct dentry *root;
846 
847 	/* open dir */
848 	dout("open_root_inode opening '%s'\n", path);
849 	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_GETATTR, USE_ANY_MDS);
850 	if (IS_ERR(req))
851 		return ERR_CAST(req);
852 	req->r_path1 = kstrdup(path, GFP_NOFS);
853 	if (!req->r_path1) {
854 		root = ERR_PTR(-ENOMEM);
855 		goto out;
856 	}
857 
858 	req->r_ino1.ino = CEPH_INO_ROOT;
859 	req->r_ino1.snap = CEPH_NOSNAP;
860 	req->r_started = started;
861 	req->r_timeout = fsc->client->options->mount_timeout;
862 	req->r_args.getattr.mask = cpu_to_le32(CEPH_STAT_CAP_INODE);
863 	req->r_num_caps = 2;
864 	err = ceph_mdsc_do_request(mdsc, NULL, req);
865 	if (err == 0) {
866 		struct inode *inode = req->r_target_inode;
867 		req->r_target_inode = NULL;
868 		dout("open_root_inode success\n");
869 		root = d_make_root(inode);
870 		if (!root) {
871 			root = ERR_PTR(-ENOMEM);
872 			goto out;
873 		}
874 		dout("open_root_inode success, root dentry is %p\n", root);
875 	} else {
876 		root = ERR_PTR(err);
877 	}
878 out:
879 	ceph_mdsc_put_request(req);
880 	return root;
881 }
882 
883 
884 
885 
886 /*
887  * mount: join the ceph cluster, and open root directory.
888  */
889 static struct dentry *ceph_real_mount(struct ceph_fs_client *fsc)
890 {
891 	int err;
892 	unsigned long started = jiffies;  /* note the start time */
893 	struct dentry *root;
894 
895 	dout("mount start %p\n", fsc);
896 	mutex_lock(&fsc->client->mount_mutex);
897 
898 	if (!fsc->sb->s_root) {
899 		const char *path;
900 		err = __ceph_open_session(fsc->client, started);
901 		if (err < 0)
902 			goto out;
903 
904 		/* setup fscache */
905 		if (fsc->mount_options->flags & CEPH_MOUNT_OPT_FSCACHE) {
906 			err = ceph_fscache_register_fs(fsc);
907 			if (err < 0)
908 				goto out;
909 		}
910 
911 		if (!fsc->mount_options->server_path) {
912 			path = "";
913 			dout("mount opening path \\t\n");
914 		} else {
915 			path = fsc->mount_options->server_path + 1;
916 			dout("mount opening path %s\n", path);
917 		}
918 
919 		err = ceph_fs_debugfs_init(fsc);
920 		if (err < 0)
921 			goto out;
922 
923 		root = open_root_dentry(fsc, path, started);
924 		if (IS_ERR(root)) {
925 			err = PTR_ERR(root);
926 			goto out;
927 		}
928 		fsc->sb->s_root = dget(root);
929 	} else {
930 		root = dget(fsc->sb->s_root);
931 	}
932 
933 	fsc->mount_state = CEPH_MOUNT_MOUNTED;
934 	dout("mount success\n");
935 	mutex_unlock(&fsc->client->mount_mutex);
936 	return root;
937 
938 out:
939 	mutex_unlock(&fsc->client->mount_mutex);
940 	return ERR_PTR(err);
941 }
942 
943 static int ceph_set_super(struct super_block *s, void *data)
944 {
945 	struct ceph_fs_client *fsc = data;
946 	int ret;
947 
948 	dout("set_super %p data %p\n", s, data);
949 
950 	s->s_flags = fsc->mount_options->sb_flags;
951 	s->s_maxbytes = MAX_LFS_FILESIZE;
952 
953 	s->s_xattr = ceph_xattr_handlers;
954 	s->s_fs_info = fsc;
955 	fsc->sb = s;
956 	fsc->max_file_size = 1ULL << 40; /* temp value until we get mdsmap */
957 
958 	s->s_op = &ceph_super_ops;
959 	s->s_d_op = &ceph_dentry_ops;
960 	s->s_export_op = &ceph_export_ops;
961 
962 	s->s_time_gran = 1000;  /* 1000 ns == 1 us */
963 
964 	ret = set_anon_super(s, NULL);  /* what is that second arg for? */
965 	if (ret != 0)
966 		goto fail;
967 
968 	return ret;
969 
970 fail:
971 	s->s_fs_info = NULL;
972 	fsc->sb = NULL;
973 	return ret;
974 }
975 
976 /*
977  * share superblock if same fs AND options
978  */
979 static int ceph_compare_super(struct super_block *sb, void *data)
980 {
981 	struct ceph_fs_client *new = data;
982 	struct ceph_mount_options *fsopt = new->mount_options;
983 	struct ceph_options *opt = new->client->options;
984 	struct ceph_fs_client *other = ceph_sb_to_client(sb);
985 
986 	dout("ceph_compare_super %p\n", sb);
987 
988 	if (compare_mount_options(fsopt, opt, other)) {
989 		dout("monitor(s)/mount options don't match\n");
990 		return 0;
991 	}
992 	if ((opt->flags & CEPH_OPT_FSID) &&
993 	    ceph_fsid_compare(&opt->fsid, &other->client->fsid)) {
994 		dout("fsid doesn't match\n");
995 		return 0;
996 	}
997 	if (fsopt->sb_flags != other->mount_options->sb_flags) {
998 		dout("flags differ\n");
999 		return 0;
1000 	}
1001 	return 1;
1002 }
1003 
1004 /*
1005  * construct our own bdi so we can control readahead, etc.
1006  */
1007 static atomic_long_t bdi_seq = ATOMIC_LONG_INIT(0);
1008 
1009 static int ceph_setup_bdi(struct super_block *sb, struct ceph_fs_client *fsc)
1010 {
1011 	int err;
1012 
1013 	err = super_setup_bdi_name(sb, "ceph-%ld",
1014 				   atomic_long_inc_return(&bdi_seq));
1015 	if (err)
1016 		return err;
1017 
1018 	/* set ra_pages based on rasize mount option? */
1019 	sb->s_bdi->ra_pages = fsc->mount_options->rasize >> PAGE_SHIFT;
1020 
1021 	/* set io_pages based on max osd read size */
1022 	sb->s_bdi->io_pages = fsc->mount_options->rsize >> PAGE_SHIFT;
1023 
1024 	return 0;
1025 }
1026 
1027 static struct dentry *ceph_mount(struct file_system_type *fs_type,
1028 		       int flags, const char *dev_name, void *data)
1029 {
1030 	struct super_block *sb;
1031 	struct ceph_fs_client *fsc;
1032 	struct dentry *res;
1033 	int err;
1034 	int (*compare_super)(struct super_block *, void *) = ceph_compare_super;
1035 	struct ceph_mount_options *fsopt = NULL;
1036 	struct ceph_options *opt = NULL;
1037 
1038 	dout("ceph_mount\n");
1039 
1040 #ifdef CONFIG_CEPH_FS_POSIX_ACL
1041 	flags |= SB_POSIXACL;
1042 #endif
1043 	err = parse_mount_options(&fsopt, &opt, flags, data, dev_name);
1044 	if (err < 0) {
1045 		res = ERR_PTR(err);
1046 		goto out_final;
1047 	}
1048 
1049 	/* create client (which we may/may not use) */
1050 	fsc = create_fs_client(fsopt, opt);
1051 	if (IS_ERR(fsc)) {
1052 		res = ERR_CAST(fsc);
1053 		goto out_final;
1054 	}
1055 
1056 	err = ceph_mdsc_init(fsc);
1057 	if (err < 0) {
1058 		res = ERR_PTR(err);
1059 		goto out;
1060 	}
1061 
1062 	if (ceph_test_opt(fsc->client, NOSHARE))
1063 		compare_super = NULL;
1064 	sb = sget(fs_type, compare_super, ceph_set_super, flags, fsc);
1065 	if (IS_ERR(sb)) {
1066 		res = ERR_CAST(sb);
1067 		goto out;
1068 	}
1069 
1070 	if (ceph_sb_to_client(sb) != fsc) {
1071 		ceph_mdsc_destroy(fsc);
1072 		destroy_fs_client(fsc);
1073 		fsc = ceph_sb_to_client(sb);
1074 		dout("get_sb got existing client %p\n", fsc);
1075 	} else {
1076 		dout("get_sb using new client %p\n", fsc);
1077 		err = ceph_setup_bdi(sb, fsc);
1078 		if (err < 0) {
1079 			res = ERR_PTR(err);
1080 			goto out_splat;
1081 		}
1082 	}
1083 
1084 	res = ceph_real_mount(fsc);
1085 	if (IS_ERR(res))
1086 		goto out_splat;
1087 	dout("root %p inode %p ino %llx.%llx\n", res,
1088 	     d_inode(res), ceph_vinop(d_inode(res)));
1089 	return res;
1090 
1091 out_splat:
1092 	ceph_mdsc_close_sessions(fsc->mdsc);
1093 	deactivate_locked_super(sb);
1094 	goto out_final;
1095 
1096 out:
1097 	ceph_mdsc_destroy(fsc);
1098 	destroy_fs_client(fsc);
1099 out_final:
1100 	dout("ceph_mount fail %ld\n", PTR_ERR(res));
1101 	return res;
1102 }
1103 
1104 static void ceph_kill_sb(struct super_block *s)
1105 {
1106 	struct ceph_fs_client *fsc = ceph_sb_to_client(s);
1107 	dev_t dev = s->s_dev;
1108 
1109 	dout("kill_sb %p\n", s);
1110 
1111 	ceph_mdsc_pre_umount(fsc->mdsc);
1112 	flush_fs_workqueues(fsc);
1113 
1114 	generic_shutdown_super(s);
1115 
1116 	fsc->client->extra_mon_dispatch = NULL;
1117 	ceph_fs_debugfs_cleanup(fsc);
1118 
1119 	ceph_fscache_unregister_fs(fsc);
1120 
1121 	ceph_mdsc_destroy(fsc);
1122 
1123 	destroy_fs_client(fsc);
1124 	free_anon_bdev(dev);
1125 }
1126 
1127 static struct file_system_type ceph_fs_type = {
1128 	.owner		= THIS_MODULE,
1129 	.name		= "ceph",
1130 	.mount		= ceph_mount,
1131 	.kill_sb	= ceph_kill_sb,
1132 	.fs_flags	= FS_RENAME_DOES_D_MOVE,
1133 };
1134 MODULE_ALIAS_FS("ceph");
1135 
1136 static int __init init_ceph(void)
1137 {
1138 	int ret = init_caches();
1139 	if (ret)
1140 		goto out;
1141 
1142 	ceph_flock_init();
1143 	ceph_xattr_init();
1144 	ret = register_filesystem(&ceph_fs_type);
1145 	if (ret)
1146 		goto out_xattr;
1147 
1148 	pr_info("loaded (mds proto %d)\n", CEPH_MDSC_PROTOCOL);
1149 
1150 	return 0;
1151 
1152 out_xattr:
1153 	ceph_xattr_exit();
1154 	destroy_caches();
1155 out:
1156 	return ret;
1157 }
1158 
1159 static void __exit exit_ceph(void)
1160 {
1161 	dout("exit_ceph\n");
1162 	unregister_filesystem(&ceph_fs_type);
1163 	ceph_xattr_exit();
1164 	destroy_caches();
1165 }
1166 
1167 module_init(init_ceph);
1168 module_exit(exit_ceph);
1169 
1170 MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
1171 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
1172 MODULE_AUTHOR("Patience Warnick <patience@newdream.net>");
1173 MODULE_DESCRIPTION("Ceph filesystem for Linux");
1174 MODULE_LICENSE("GPL");
1175