xref: /openbmc/linux/fs/ceph/super.c (revision f7d84fa7)
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_monmap *monmap = fsc->client->monc.monmap;
49 	struct ceph_statfs st;
50 	u64 fsid;
51 	int err;
52 
53 	dout("statfs\n");
54 	err = ceph_monc_do_statfs(&fsc->client->monc, &st);
55 	if (err < 0)
56 		return err;
57 
58 	/* fill in kstatfs */
59 	buf->f_type = CEPH_SUPER_MAGIC;  /* ?? */
60 
61 	/*
62 	 * express utilization in terms of large blocks to avoid
63 	 * overflow on 32-bit machines.
64 	 *
65 	 * NOTE: for the time being, we make bsize == frsize to humor
66 	 * not-yet-ancient versions of glibc that are broken.
67 	 * Someday, we will probably want to report a real block
68 	 * size...  whatever that may mean for a network file system!
69 	 */
70 	buf->f_bsize = 1 << CEPH_BLOCK_SHIFT;
71 	buf->f_frsize = 1 << CEPH_BLOCK_SHIFT;
72 	buf->f_blocks = le64_to_cpu(st.kb) >> (CEPH_BLOCK_SHIFT-10);
73 	buf->f_bfree = le64_to_cpu(st.kb_avail) >> (CEPH_BLOCK_SHIFT-10);
74 	buf->f_bavail = le64_to_cpu(st.kb_avail) >> (CEPH_BLOCK_SHIFT-10);
75 
76 	buf->f_files = le64_to_cpu(st.num_objects);
77 	buf->f_ffree = -1;
78 	buf->f_namelen = NAME_MAX;
79 
80 	/* leave fsid little-endian, regardless of host endianness */
81 	fsid = *(u64 *)(&monmap->fsid) ^ *((u64 *)&monmap->fsid + 1);
82 	buf->f_fsid.val[0] = fsid & 0xffffffff;
83 	buf->f_fsid.val[1] = fsid >> 32;
84 
85 	return 0;
86 }
87 
88 
89 static int ceph_sync_fs(struct super_block *sb, int wait)
90 {
91 	struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
92 
93 	if (!wait) {
94 		dout("sync_fs (non-blocking)\n");
95 		ceph_flush_dirty_caps(fsc->mdsc);
96 		dout("sync_fs (non-blocking) done\n");
97 		return 0;
98 	}
99 
100 	dout("sync_fs (blocking)\n");
101 	ceph_osdc_sync(&fsc->client->osdc);
102 	ceph_mdsc_sync(fsc->mdsc);
103 	dout("sync_fs (blocking) done\n");
104 	return 0;
105 }
106 
107 /*
108  * mount options
109  */
110 enum {
111 	Opt_wsize,
112 	Opt_rsize,
113 	Opt_rasize,
114 	Opt_caps_wanted_delay_min,
115 	Opt_caps_wanted_delay_max,
116 	Opt_cap_release_safety,
117 	Opt_readdir_max_entries,
118 	Opt_readdir_max_bytes,
119 	Opt_congestion_kb,
120 	Opt_last_int,
121 	/* int args above */
122 	Opt_snapdirname,
123 	Opt_mds_namespace,
124 	Opt_last_string,
125 	/* string args above */
126 	Opt_dirstat,
127 	Opt_nodirstat,
128 	Opt_rbytes,
129 	Opt_norbytes,
130 	Opt_asyncreaddir,
131 	Opt_noasyncreaddir,
132 	Opt_dcache,
133 	Opt_nodcache,
134 	Opt_ino32,
135 	Opt_noino32,
136 	Opt_fscache,
137 	Opt_nofscache,
138 	Opt_poolperm,
139 	Opt_nopoolperm,
140 	Opt_require_active_mds,
141 	Opt_norequire_active_mds,
142 #ifdef CONFIG_CEPH_FS_POSIX_ACL
143 	Opt_acl,
144 #endif
145 	Opt_noacl,
146 };
147 
148 static match_table_t fsopt_tokens = {
149 	{Opt_wsize, "wsize=%d"},
150 	{Opt_rsize, "rsize=%d"},
151 	{Opt_rasize, "rasize=%d"},
152 	{Opt_caps_wanted_delay_min, "caps_wanted_delay_min=%d"},
153 	{Opt_caps_wanted_delay_max, "caps_wanted_delay_max=%d"},
154 	{Opt_cap_release_safety, "cap_release_safety=%d"},
155 	{Opt_readdir_max_entries, "readdir_max_entries=%d"},
156 	{Opt_readdir_max_bytes, "readdir_max_bytes=%d"},
157 	{Opt_congestion_kb, "write_congestion_kb=%d"},
158 	/* int args above */
159 	{Opt_snapdirname, "snapdirname=%s"},
160 	{Opt_mds_namespace, "mds_namespace=%s"},
161 	/* string args above */
162 	{Opt_dirstat, "dirstat"},
163 	{Opt_nodirstat, "nodirstat"},
164 	{Opt_rbytes, "rbytes"},
165 	{Opt_norbytes, "norbytes"},
166 	{Opt_asyncreaddir, "asyncreaddir"},
167 	{Opt_noasyncreaddir, "noasyncreaddir"},
168 	{Opt_dcache, "dcache"},
169 	{Opt_nodcache, "nodcache"},
170 	{Opt_ino32, "ino32"},
171 	{Opt_noino32, "noino32"},
172 	{Opt_fscache, "fsc"},
173 	{Opt_nofscache, "nofsc"},
174 	{Opt_poolperm, "poolperm"},
175 	{Opt_nopoolperm, "nopoolperm"},
176 	{Opt_require_active_mds, "require_active_mds"},
177 	{Opt_norequire_active_mds, "norequire_active_mds"},
178 #ifdef CONFIG_CEPH_FS_POSIX_ACL
179 	{Opt_acl, "acl"},
180 #endif
181 	{Opt_noacl, "noacl"},
182 	{-1, NULL}
183 };
184 
185 static int parse_fsopt_token(char *c, void *private)
186 {
187 	struct ceph_mount_options *fsopt = private;
188 	substring_t argstr[MAX_OPT_ARGS];
189 	int token, intval, ret;
190 
191 	token = match_token((char *)c, fsopt_tokens, argstr);
192 	if (token < 0)
193 		return -EINVAL;
194 
195 	if (token < Opt_last_int) {
196 		ret = match_int(&argstr[0], &intval);
197 		if (ret < 0) {
198 			pr_err("bad mount option arg (not int) "
199 			       "at '%s'\n", c);
200 			return ret;
201 		}
202 		dout("got int token %d val %d\n", token, intval);
203 	} else if (token > Opt_last_int && token < Opt_last_string) {
204 		dout("got string token %d val %s\n", token,
205 		     argstr[0].from);
206 	} else {
207 		dout("got token %d\n", token);
208 	}
209 
210 	switch (token) {
211 	case Opt_snapdirname:
212 		kfree(fsopt->snapdir_name);
213 		fsopt->snapdir_name = kstrndup(argstr[0].from,
214 					       argstr[0].to-argstr[0].from,
215 					       GFP_KERNEL);
216 		if (!fsopt->snapdir_name)
217 			return -ENOMEM;
218 		break;
219 	case Opt_mds_namespace:
220 		fsopt->mds_namespace = kstrndup(argstr[0].from,
221 						argstr[0].to-argstr[0].from,
222 						GFP_KERNEL);
223 		if (!fsopt->mds_namespace)
224 			return -ENOMEM;
225 		break;
226 		/* misc */
227 	case Opt_wsize:
228 		fsopt->wsize = intval;
229 		break;
230 	case Opt_rsize:
231 		fsopt->rsize = intval;
232 		break;
233 	case Opt_rasize:
234 		fsopt->rasize = intval;
235 		break;
236 	case Opt_caps_wanted_delay_min:
237 		fsopt->caps_wanted_delay_min = intval;
238 		break;
239 	case Opt_caps_wanted_delay_max:
240 		fsopt->caps_wanted_delay_max = intval;
241 		break;
242 	case Opt_readdir_max_entries:
243 		fsopt->max_readdir = intval;
244 		break;
245 	case Opt_readdir_max_bytes:
246 		fsopt->max_readdir_bytes = intval;
247 		break;
248 	case Opt_congestion_kb:
249 		fsopt->congestion_kb = intval;
250 		break;
251 	case Opt_dirstat:
252 		fsopt->flags |= CEPH_MOUNT_OPT_DIRSTAT;
253 		break;
254 	case Opt_nodirstat:
255 		fsopt->flags &= ~CEPH_MOUNT_OPT_DIRSTAT;
256 		break;
257 	case Opt_rbytes:
258 		fsopt->flags |= CEPH_MOUNT_OPT_RBYTES;
259 		break;
260 	case Opt_norbytes:
261 		fsopt->flags &= ~CEPH_MOUNT_OPT_RBYTES;
262 		break;
263 	case Opt_asyncreaddir:
264 		fsopt->flags &= ~CEPH_MOUNT_OPT_NOASYNCREADDIR;
265 		break;
266 	case Opt_noasyncreaddir:
267 		fsopt->flags |= CEPH_MOUNT_OPT_NOASYNCREADDIR;
268 		break;
269 	case Opt_dcache:
270 		fsopt->flags |= CEPH_MOUNT_OPT_DCACHE;
271 		break;
272 	case Opt_nodcache:
273 		fsopt->flags &= ~CEPH_MOUNT_OPT_DCACHE;
274 		break;
275 	case Opt_ino32:
276 		fsopt->flags |= CEPH_MOUNT_OPT_INO32;
277 		break;
278 	case Opt_noino32:
279 		fsopt->flags &= ~CEPH_MOUNT_OPT_INO32;
280 		break;
281 	case Opt_fscache:
282 		fsopt->flags |= CEPH_MOUNT_OPT_FSCACHE;
283 		break;
284 	case Opt_nofscache:
285 		fsopt->flags &= ~CEPH_MOUNT_OPT_FSCACHE;
286 		break;
287 	case Opt_poolperm:
288 		fsopt->flags &= ~CEPH_MOUNT_OPT_NOPOOLPERM;
289 		printk ("pool perm");
290 		break;
291 	case Opt_nopoolperm:
292 		fsopt->flags |= CEPH_MOUNT_OPT_NOPOOLPERM;
293 		break;
294 	case Opt_require_active_mds:
295 		fsopt->flags &= ~CEPH_MOUNT_OPT_MOUNTWAIT;
296 		break;
297 	case Opt_norequire_active_mds:
298 		fsopt->flags |= CEPH_MOUNT_OPT_MOUNTWAIT;
299 		break;
300 #ifdef CONFIG_CEPH_FS_POSIX_ACL
301 	case Opt_acl:
302 		fsopt->sb_flags |= MS_POSIXACL;
303 		break;
304 #endif
305 	case Opt_noacl:
306 		fsopt->sb_flags &= ~MS_POSIXACL;
307 		break;
308 	default:
309 		BUG_ON(token);
310 	}
311 	return 0;
312 }
313 
314 static void destroy_mount_options(struct ceph_mount_options *args)
315 {
316 	dout("destroy_mount_options %p\n", args);
317 	kfree(args->snapdir_name);
318 	kfree(args->mds_namespace);
319 	kfree(args->server_path);
320 	kfree(args);
321 }
322 
323 static int strcmp_null(const char *s1, const char *s2)
324 {
325 	if (!s1 && !s2)
326 		return 0;
327 	if (s1 && !s2)
328 		return -1;
329 	if (!s1 && s2)
330 		return 1;
331 	return strcmp(s1, s2);
332 }
333 
334 static int compare_mount_options(struct ceph_mount_options *new_fsopt,
335 				 struct ceph_options *new_opt,
336 				 struct ceph_fs_client *fsc)
337 {
338 	struct ceph_mount_options *fsopt1 = new_fsopt;
339 	struct ceph_mount_options *fsopt2 = fsc->mount_options;
340 	int ofs = offsetof(struct ceph_mount_options, snapdir_name);
341 	int ret;
342 
343 	ret = memcmp(fsopt1, fsopt2, ofs);
344 	if (ret)
345 		return ret;
346 
347 	ret = strcmp_null(fsopt1->snapdir_name, fsopt2->snapdir_name);
348 	if (ret)
349 		return ret;
350 	ret = strcmp_null(fsopt1->mds_namespace, fsopt2->mds_namespace);
351 	if (ret)
352 		return ret;
353 
354 	ret = strcmp_null(fsopt1->server_path, fsopt2->server_path);
355 	if (ret)
356 		return ret;
357 
358 	return ceph_compare_options(new_opt, fsc->client);
359 }
360 
361 static int parse_mount_options(struct ceph_mount_options **pfsopt,
362 			       struct ceph_options **popt,
363 			       int flags, char *options,
364 			       const char *dev_name)
365 {
366 	struct ceph_mount_options *fsopt;
367 	const char *dev_name_end;
368 	int err;
369 
370 	if (!dev_name || !*dev_name)
371 		return -EINVAL;
372 
373 	fsopt = kzalloc(sizeof(*fsopt), GFP_KERNEL);
374 	if (!fsopt)
375 		return -ENOMEM;
376 
377 	dout("parse_mount_options %p, dev_name '%s'\n", fsopt, dev_name);
378 
379 	fsopt->sb_flags = flags;
380 	fsopt->flags = CEPH_MOUNT_OPT_DEFAULT;
381 
382 	fsopt->rsize = CEPH_RSIZE_DEFAULT;
383 	fsopt->rasize = CEPH_RASIZE_DEFAULT;
384 	fsopt->snapdir_name = kstrdup(CEPH_SNAPDIRNAME_DEFAULT, GFP_KERNEL);
385 	if (!fsopt->snapdir_name) {
386 		err = -ENOMEM;
387 		goto out;
388 	}
389 
390 	fsopt->caps_wanted_delay_min = CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT;
391 	fsopt->caps_wanted_delay_max = CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT;
392 	fsopt->cap_release_safety = CEPH_CAP_RELEASE_SAFETY_DEFAULT;
393 	fsopt->max_readdir = CEPH_MAX_READDIR_DEFAULT;
394 	fsopt->max_readdir_bytes = CEPH_MAX_READDIR_BYTES_DEFAULT;
395 	fsopt->congestion_kb = default_congestion_kb();
396 
397 	/*
398 	 * Distinguish the server list from the path in "dev_name".
399 	 * Internally we do not include the leading '/' in the path.
400 	 *
401 	 * "dev_name" will look like:
402 	 *     <server_spec>[,<server_spec>...]:[<path>]
403 	 * where
404 	 *     <server_spec> is <ip>[:<port>]
405 	 *     <path> is optional, but if present must begin with '/'
406 	 */
407 	dev_name_end = strchr(dev_name, '/');
408 	if (dev_name_end) {
409 		if (strlen(dev_name_end) > 1) {
410 			fsopt->server_path = kstrdup(dev_name_end, GFP_KERNEL);
411 			if (!fsopt->server_path) {
412 				err = -ENOMEM;
413 				goto out;
414 			}
415 		}
416 	} else {
417 		dev_name_end = dev_name + strlen(dev_name);
418 	}
419 	err = -EINVAL;
420 	dev_name_end--;		/* back up to ':' separator */
421 	if (dev_name_end < dev_name || *dev_name_end != ':') {
422 		pr_err("device name is missing path (no : separator in %s)\n",
423 				dev_name);
424 		goto out;
425 	}
426 	dout("device name '%.*s'\n", (int)(dev_name_end - dev_name), dev_name);
427 	if (fsopt->server_path)
428 		dout("server path '%s'\n", fsopt->server_path);
429 
430 	*popt = ceph_parse_options(options, dev_name, dev_name_end,
431 				 parse_fsopt_token, (void *)fsopt);
432 	if (IS_ERR(*popt)) {
433 		err = PTR_ERR(*popt);
434 		goto out;
435 	}
436 
437 	/* success */
438 	*pfsopt = fsopt;
439 	return 0;
440 
441 out:
442 	destroy_mount_options(fsopt);
443 	return err;
444 }
445 
446 /**
447  * ceph_show_options - Show mount options in /proc/mounts
448  * @m: seq_file to write to
449  * @root: root of that (sub)tree
450  */
451 static int ceph_show_options(struct seq_file *m, struct dentry *root)
452 {
453 	struct ceph_fs_client *fsc = ceph_sb_to_client(root->d_sb);
454 	struct ceph_mount_options *fsopt = fsc->mount_options;
455 	size_t pos;
456 	int ret;
457 
458 	/* a comma between MNT/MS and client options */
459 	seq_putc(m, ',');
460 	pos = m->count;
461 
462 	ret = ceph_print_client_options(m, fsc->client);
463 	if (ret)
464 		return ret;
465 
466 	/* retract our comma if no client options */
467 	if (m->count == pos)
468 		m->count--;
469 
470 	if (fsopt->flags & CEPH_MOUNT_OPT_DIRSTAT)
471 		seq_puts(m, ",dirstat");
472 	if ((fsopt->flags & CEPH_MOUNT_OPT_RBYTES))
473 		seq_puts(m, ",rbytes");
474 	if (fsopt->flags & CEPH_MOUNT_OPT_NOASYNCREADDIR)
475 		seq_puts(m, ",noasyncreaddir");
476 	if ((fsopt->flags & CEPH_MOUNT_OPT_DCACHE) == 0)
477 		seq_puts(m, ",nodcache");
478 	if (fsopt->flags & CEPH_MOUNT_OPT_FSCACHE)
479 		seq_puts(m, ",fsc");
480 	if (fsopt->flags & CEPH_MOUNT_OPT_NOPOOLPERM)
481 		seq_puts(m, ",nopoolperm");
482 
483 #ifdef CONFIG_CEPH_FS_POSIX_ACL
484 	if (fsopt->sb_flags & MS_POSIXACL)
485 		seq_puts(m, ",acl");
486 	else
487 		seq_puts(m, ",noacl");
488 #endif
489 
490 	if (fsopt->mds_namespace)
491 		seq_printf(m, ",mds_namespace=%s", fsopt->mds_namespace);
492 	if (fsopt->wsize)
493 		seq_printf(m, ",wsize=%d", fsopt->wsize);
494 	if (fsopt->rsize != CEPH_RSIZE_DEFAULT)
495 		seq_printf(m, ",rsize=%d", fsopt->rsize);
496 	if (fsopt->rasize != CEPH_RASIZE_DEFAULT)
497 		seq_printf(m, ",rasize=%d", fsopt->rasize);
498 	if (fsopt->congestion_kb != default_congestion_kb())
499 		seq_printf(m, ",write_congestion_kb=%d", fsopt->congestion_kb);
500 	if (fsopt->caps_wanted_delay_min != CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT)
501 		seq_printf(m, ",caps_wanted_delay_min=%d",
502 			 fsopt->caps_wanted_delay_min);
503 	if (fsopt->caps_wanted_delay_max != CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT)
504 		seq_printf(m, ",caps_wanted_delay_max=%d",
505 			   fsopt->caps_wanted_delay_max);
506 	if (fsopt->cap_release_safety != CEPH_CAP_RELEASE_SAFETY_DEFAULT)
507 		seq_printf(m, ",cap_release_safety=%d",
508 			   fsopt->cap_release_safety);
509 	if (fsopt->max_readdir != CEPH_MAX_READDIR_DEFAULT)
510 		seq_printf(m, ",readdir_max_entries=%d", fsopt->max_readdir);
511 	if (fsopt->max_readdir_bytes != CEPH_MAX_READDIR_BYTES_DEFAULT)
512 		seq_printf(m, ",readdir_max_bytes=%d", fsopt->max_readdir_bytes);
513 	if (strcmp(fsopt->snapdir_name, CEPH_SNAPDIRNAME_DEFAULT))
514 		seq_show_option(m, "snapdirname", fsopt->snapdir_name);
515 
516 	return 0;
517 }
518 
519 /*
520  * handle any mon messages the standard library doesn't understand.
521  * return error if we don't either.
522  */
523 static int extra_mon_dispatch(struct ceph_client *client, struct ceph_msg *msg)
524 {
525 	struct ceph_fs_client *fsc = client->private;
526 	int type = le16_to_cpu(msg->hdr.type);
527 
528 	switch (type) {
529 	case CEPH_MSG_MDS_MAP:
530 		ceph_mdsc_handle_mdsmap(fsc->mdsc, msg);
531 		return 0;
532 	case CEPH_MSG_FS_MAP_USER:
533 		ceph_mdsc_handle_fsmap(fsc->mdsc, msg);
534 		return 0;
535 	default:
536 		return -1;
537 	}
538 }
539 
540 /*
541  * create a new fs client
542  */
543 static struct ceph_fs_client *create_fs_client(struct ceph_mount_options *fsopt,
544 					struct ceph_options *opt)
545 {
546 	struct ceph_fs_client *fsc;
547 	int page_count;
548 	size_t size;
549 	int err = -ENOMEM;
550 
551 	fsc = kzalloc(sizeof(*fsc), GFP_KERNEL);
552 	if (!fsc)
553 		return ERR_PTR(-ENOMEM);
554 
555 	fsc->client = ceph_create_client(opt, fsc);
556 	if (IS_ERR(fsc->client)) {
557 		err = PTR_ERR(fsc->client);
558 		goto fail;
559 	}
560 	fsc->client->extra_mon_dispatch = extra_mon_dispatch;
561 
562 	if (fsopt->mds_namespace == NULL) {
563 		ceph_monc_want_map(&fsc->client->monc, CEPH_SUB_MDSMAP,
564 				   0, true);
565 	} else {
566 		ceph_monc_want_map(&fsc->client->monc, CEPH_SUB_FSMAP,
567 				   0, false);
568 	}
569 
570 	fsc->mount_options = fsopt;
571 
572 	fsc->sb = NULL;
573 	fsc->mount_state = CEPH_MOUNT_MOUNTING;
574 
575 	atomic_long_set(&fsc->writeback_count, 0);
576 
577 	err = -ENOMEM;
578 	/*
579 	 * The number of concurrent works can be high but they don't need
580 	 * to be processed in parallel, limit concurrency.
581 	 */
582 	fsc->wb_wq = alloc_workqueue("ceph-writeback", 0, 1);
583 	if (fsc->wb_wq == NULL)
584 		goto fail_client;
585 	fsc->pg_inv_wq = alloc_workqueue("ceph-pg-invalid", 0, 1);
586 	if (fsc->pg_inv_wq == NULL)
587 		goto fail_wb_wq;
588 	fsc->trunc_wq = alloc_workqueue("ceph-trunc", 0, 1);
589 	if (fsc->trunc_wq == NULL)
590 		goto fail_pg_inv_wq;
591 
592 	/* set up mempools */
593 	err = -ENOMEM;
594 	page_count = fsc->mount_options->wsize >> PAGE_SHIFT;
595 	size = sizeof (struct page *) * (page_count ? page_count : 1);
596 	fsc->wb_pagevec_pool = mempool_create_kmalloc_pool(10, size);
597 	if (!fsc->wb_pagevec_pool)
598 		goto fail_trunc_wq;
599 
600 	/* setup fscache */
601 	if ((fsopt->flags & CEPH_MOUNT_OPT_FSCACHE) &&
602 	    (ceph_fscache_register_fs(fsc) != 0))
603 		goto fail_fscache;
604 
605 	/* caps */
606 	fsc->min_caps = fsopt->max_readdir;
607 
608 	return fsc;
609 
610 fail_fscache:
611 	ceph_fscache_unregister_fs(fsc);
612 fail_trunc_wq:
613 	destroy_workqueue(fsc->trunc_wq);
614 fail_pg_inv_wq:
615 	destroy_workqueue(fsc->pg_inv_wq);
616 fail_wb_wq:
617 	destroy_workqueue(fsc->wb_wq);
618 fail_client:
619 	ceph_destroy_client(fsc->client);
620 fail:
621 	kfree(fsc);
622 	return ERR_PTR(err);
623 }
624 
625 static void destroy_fs_client(struct ceph_fs_client *fsc)
626 {
627 	dout("destroy_fs_client %p\n", fsc);
628 
629 	ceph_fscache_unregister_fs(fsc);
630 
631 	destroy_workqueue(fsc->wb_wq);
632 	destroy_workqueue(fsc->pg_inv_wq);
633 	destroy_workqueue(fsc->trunc_wq);
634 
635 	mempool_destroy(fsc->wb_pagevec_pool);
636 
637 	destroy_mount_options(fsc->mount_options);
638 
639 	ceph_fs_debugfs_cleanup(fsc);
640 
641 	ceph_destroy_client(fsc->client);
642 
643 	kfree(fsc);
644 	dout("destroy_fs_client %p done\n", fsc);
645 }
646 
647 /*
648  * caches
649  */
650 struct kmem_cache *ceph_inode_cachep;
651 struct kmem_cache *ceph_cap_cachep;
652 struct kmem_cache *ceph_cap_flush_cachep;
653 struct kmem_cache *ceph_dentry_cachep;
654 struct kmem_cache *ceph_file_cachep;
655 
656 static void ceph_inode_init_once(void *foo)
657 {
658 	struct ceph_inode_info *ci = foo;
659 	inode_init_once(&ci->vfs_inode);
660 }
661 
662 static int __init init_caches(void)
663 {
664 	int error = -ENOMEM;
665 
666 	ceph_inode_cachep = kmem_cache_create("ceph_inode_info",
667 				      sizeof(struct ceph_inode_info),
668 				      __alignof__(struct ceph_inode_info),
669 				      SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
670 				      SLAB_ACCOUNT, ceph_inode_init_once);
671 	if (ceph_inode_cachep == NULL)
672 		return -ENOMEM;
673 
674 	ceph_cap_cachep = KMEM_CACHE(ceph_cap,
675 				     SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
676 	if (ceph_cap_cachep == NULL)
677 		goto bad_cap;
678 	ceph_cap_flush_cachep = KMEM_CACHE(ceph_cap_flush,
679 					   SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
680 	if (ceph_cap_flush_cachep == NULL)
681 		goto bad_cap_flush;
682 
683 	ceph_dentry_cachep = KMEM_CACHE(ceph_dentry_info,
684 					SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
685 	if (ceph_dentry_cachep == NULL)
686 		goto bad_dentry;
687 
688 	ceph_file_cachep = KMEM_CACHE(ceph_file_info, SLAB_MEM_SPREAD);
689 
690 	if (ceph_file_cachep == NULL)
691 		goto bad_file;
692 
693 	if ((error = ceph_fscache_register()))
694 		goto bad_file;
695 
696 	return 0;
697 bad_file:
698 	kmem_cache_destroy(ceph_dentry_cachep);
699 bad_dentry:
700 	kmem_cache_destroy(ceph_cap_flush_cachep);
701 bad_cap_flush:
702 	kmem_cache_destroy(ceph_cap_cachep);
703 bad_cap:
704 	kmem_cache_destroy(ceph_inode_cachep);
705 	return error;
706 }
707 
708 static void destroy_caches(void)
709 {
710 	/*
711 	 * Make sure all delayed rcu free inodes are flushed before we
712 	 * destroy cache.
713 	 */
714 	rcu_barrier();
715 
716 	kmem_cache_destroy(ceph_inode_cachep);
717 	kmem_cache_destroy(ceph_cap_cachep);
718 	kmem_cache_destroy(ceph_cap_flush_cachep);
719 	kmem_cache_destroy(ceph_dentry_cachep);
720 	kmem_cache_destroy(ceph_file_cachep);
721 
722 	ceph_fscache_unregister();
723 }
724 
725 
726 /*
727  * ceph_umount_begin - initiate forced umount.  Tear down down the
728  * mount, skipping steps that may hang while waiting for server(s).
729  */
730 static void ceph_umount_begin(struct super_block *sb)
731 {
732 	struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
733 
734 	dout("ceph_umount_begin - starting forced umount\n");
735 	if (!fsc)
736 		return;
737 	fsc->mount_state = CEPH_MOUNT_SHUTDOWN;
738 	ceph_mdsc_force_umount(fsc->mdsc);
739 	return;
740 }
741 
742 static const struct super_operations ceph_super_ops = {
743 	.alloc_inode	= ceph_alloc_inode,
744 	.destroy_inode	= ceph_destroy_inode,
745 	.write_inode    = ceph_write_inode,
746 	.drop_inode	= ceph_drop_inode,
747 	.sync_fs        = ceph_sync_fs,
748 	.put_super	= ceph_put_super,
749 	.show_options   = ceph_show_options,
750 	.statfs		= ceph_statfs,
751 	.umount_begin   = ceph_umount_begin,
752 };
753 
754 /*
755  * Bootstrap mount by opening the root directory.  Note the mount
756  * @started time from caller, and time out if this takes too long.
757  */
758 static struct dentry *open_root_dentry(struct ceph_fs_client *fsc,
759 				       const char *path,
760 				       unsigned long started)
761 {
762 	struct ceph_mds_client *mdsc = fsc->mdsc;
763 	struct ceph_mds_request *req = NULL;
764 	int err;
765 	struct dentry *root;
766 
767 	/* open dir */
768 	dout("open_root_inode opening '%s'\n", path);
769 	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_GETATTR, USE_ANY_MDS);
770 	if (IS_ERR(req))
771 		return ERR_CAST(req);
772 	req->r_path1 = kstrdup(path, GFP_NOFS);
773 	if (!req->r_path1) {
774 		root = ERR_PTR(-ENOMEM);
775 		goto out;
776 	}
777 
778 	req->r_ino1.ino = CEPH_INO_ROOT;
779 	req->r_ino1.snap = CEPH_NOSNAP;
780 	req->r_started = started;
781 	req->r_timeout = fsc->client->options->mount_timeout;
782 	req->r_args.getattr.mask = cpu_to_le32(CEPH_STAT_CAP_INODE);
783 	req->r_num_caps = 2;
784 	err = ceph_mdsc_do_request(mdsc, NULL, req);
785 	if (err == 0) {
786 		struct inode *inode = req->r_target_inode;
787 		req->r_target_inode = NULL;
788 		dout("open_root_inode success\n");
789 		root = d_make_root(inode);
790 		if (!root) {
791 			root = ERR_PTR(-ENOMEM);
792 			goto out;
793 		}
794 		dout("open_root_inode success, root dentry is %p\n", root);
795 	} else {
796 		root = ERR_PTR(err);
797 	}
798 out:
799 	ceph_mdsc_put_request(req);
800 	return root;
801 }
802 
803 
804 
805 
806 /*
807  * mount: join the ceph cluster, and open root directory.
808  */
809 static struct dentry *ceph_real_mount(struct ceph_fs_client *fsc)
810 {
811 	int err;
812 	unsigned long started = jiffies;  /* note the start time */
813 	struct dentry *root;
814 	int first = 0;   /* first vfsmount for this super_block */
815 
816 	dout("mount start %p\n", fsc);
817 	mutex_lock(&fsc->client->mount_mutex);
818 
819 	if (!fsc->sb->s_root) {
820 		const char *path;
821 		err = __ceph_open_session(fsc->client, started);
822 		if (err < 0)
823 			goto out;
824 
825 		if (!fsc->mount_options->server_path) {
826 			path = "";
827 			dout("mount opening path \\t\n");
828 		} else {
829 			path = fsc->mount_options->server_path + 1;
830 			dout("mount opening path %s\n", path);
831 		}
832 		root = open_root_dentry(fsc, path, started);
833 		if (IS_ERR(root)) {
834 			err = PTR_ERR(root);
835 			goto out;
836 		}
837 		fsc->sb->s_root = dget(root);
838 		first = 1;
839 
840 		err = ceph_fs_debugfs_init(fsc);
841 		if (err < 0)
842 			goto fail;
843 	} else {
844 		root = dget(fsc->sb->s_root);
845 	}
846 
847 	fsc->mount_state = CEPH_MOUNT_MOUNTED;
848 	dout("mount success\n");
849 	mutex_unlock(&fsc->client->mount_mutex);
850 	return root;
851 
852 fail:
853 	if (first) {
854 		dput(fsc->sb->s_root);
855 		fsc->sb->s_root = NULL;
856 	}
857 out:
858 	mutex_unlock(&fsc->client->mount_mutex);
859 	return ERR_PTR(err);
860 }
861 
862 static int ceph_set_super(struct super_block *s, void *data)
863 {
864 	struct ceph_fs_client *fsc = data;
865 	int ret;
866 
867 	dout("set_super %p data %p\n", s, data);
868 
869 	s->s_flags = fsc->mount_options->sb_flags;
870 	s->s_maxbytes = 1ULL << 40;  /* temp value until we get mdsmap */
871 
872 	s->s_xattr = ceph_xattr_handlers;
873 	s->s_fs_info = fsc;
874 	fsc->sb = s;
875 
876 	s->s_op = &ceph_super_ops;
877 	s->s_d_op = &ceph_dentry_ops;
878 	s->s_export_op = &ceph_export_ops;
879 
880 	s->s_time_gran = 1000;  /* 1000 ns == 1 us */
881 
882 	ret = set_anon_super(s, NULL);  /* what is that second arg for? */
883 	if (ret != 0)
884 		goto fail;
885 
886 	return ret;
887 
888 fail:
889 	s->s_fs_info = NULL;
890 	fsc->sb = NULL;
891 	return ret;
892 }
893 
894 /*
895  * share superblock if same fs AND options
896  */
897 static int ceph_compare_super(struct super_block *sb, void *data)
898 {
899 	struct ceph_fs_client *new = data;
900 	struct ceph_mount_options *fsopt = new->mount_options;
901 	struct ceph_options *opt = new->client->options;
902 	struct ceph_fs_client *other = ceph_sb_to_client(sb);
903 
904 	dout("ceph_compare_super %p\n", sb);
905 
906 	if (compare_mount_options(fsopt, opt, other)) {
907 		dout("monitor(s)/mount options don't match\n");
908 		return 0;
909 	}
910 	if ((opt->flags & CEPH_OPT_FSID) &&
911 	    ceph_fsid_compare(&opt->fsid, &other->client->fsid)) {
912 		dout("fsid doesn't match\n");
913 		return 0;
914 	}
915 	if (fsopt->sb_flags != other->mount_options->sb_flags) {
916 		dout("flags differ\n");
917 		return 0;
918 	}
919 	return 1;
920 }
921 
922 /*
923  * construct our own bdi so we can control readahead, etc.
924  */
925 static atomic_long_t bdi_seq = ATOMIC_LONG_INIT(0);
926 
927 static int ceph_setup_bdi(struct super_block *sb, struct ceph_fs_client *fsc)
928 {
929 	int err;
930 
931 	err = super_setup_bdi_name(sb, "ceph-%ld",
932 				   atomic_long_inc_return(&bdi_seq));
933 	if (err)
934 		return err;
935 
936 	/* set ra_pages based on rasize mount option? */
937 	if (fsc->mount_options->rasize >= PAGE_SIZE)
938 		sb->s_bdi->ra_pages =
939 			(fsc->mount_options->rasize + PAGE_SIZE - 1)
940 			>> PAGE_SHIFT;
941 	else
942 		sb->s_bdi->ra_pages = VM_MAX_READAHEAD * 1024 / PAGE_SIZE;
943 
944 	if (fsc->mount_options->rsize > fsc->mount_options->rasize &&
945 	    fsc->mount_options->rsize >= PAGE_SIZE)
946 		sb->s_bdi->io_pages =
947 			(fsc->mount_options->rsize + PAGE_SIZE - 1)
948 			>> PAGE_SHIFT;
949 	else if (fsc->mount_options->rsize == 0)
950 		sb->s_bdi->io_pages = ULONG_MAX;
951 
952 	return 0;
953 }
954 
955 static struct dentry *ceph_mount(struct file_system_type *fs_type,
956 		       int flags, const char *dev_name, void *data)
957 {
958 	struct super_block *sb;
959 	struct ceph_fs_client *fsc;
960 	struct dentry *res;
961 	int err;
962 	int (*compare_super)(struct super_block *, void *) = ceph_compare_super;
963 	struct ceph_mount_options *fsopt = NULL;
964 	struct ceph_options *opt = NULL;
965 
966 	dout("ceph_mount\n");
967 
968 #ifdef CONFIG_CEPH_FS_POSIX_ACL
969 	flags |= MS_POSIXACL;
970 #endif
971 	err = parse_mount_options(&fsopt, &opt, flags, data, dev_name);
972 	if (err < 0) {
973 		res = ERR_PTR(err);
974 		goto out_final;
975 	}
976 
977 	/* create client (which we may/may not use) */
978 	fsc = create_fs_client(fsopt, opt);
979 	if (IS_ERR(fsc)) {
980 		res = ERR_CAST(fsc);
981 		destroy_mount_options(fsopt);
982 		ceph_destroy_options(opt);
983 		goto out_final;
984 	}
985 
986 	err = ceph_mdsc_init(fsc);
987 	if (err < 0) {
988 		res = ERR_PTR(err);
989 		goto out;
990 	}
991 
992 	if (ceph_test_opt(fsc->client, NOSHARE))
993 		compare_super = NULL;
994 	sb = sget(fs_type, compare_super, ceph_set_super, flags, fsc);
995 	if (IS_ERR(sb)) {
996 		res = ERR_CAST(sb);
997 		goto out;
998 	}
999 
1000 	if (ceph_sb_to_client(sb) != fsc) {
1001 		ceph_mdsc_destroy(fsc);
1002 		destroy_fs_client(fsc);
1003 		fsc = ceph_sb_to_client(sb);
1004 		dout("get_sb got existing client %p\n", fsc);
1005 	} else {
1006 		dout("get_sb using new client %p\n", fsc);
1007 		err = ceph_setup_bdi(sb, fsc);
1008 		if (err < 0) {
1009 			res = ERR_PTR(err);
1010 			goto out_splat;
1011 		}
1012 	}
1013 
1014 	res = ceph_real_mount(fsc);
1015 	if (IS_ERR(res))
1016 		goto out_splat;
1017 	dout("root %p inode %p ino %llx.%llx\n", res,
1018 	     d_inode(res), ceph_vinop(d_inode(res)));
1019 	return res;
1020 
1021 out_splat:
1022 	ceph_mdsc_close_sessions(fsc->mdsc);
1023 	deactivate_locked_super(sb);
1024 	goto out_final;
1025 
1026 out:
1027 	ceph_mdsc_destroy(fsc);
1028 	destroy_fs_client(fsc);
1029 out_final:
1030 	dout("ceph_mount fail %ld\n", PTR_ERR(res));
1031 	return res;
1032 }
1033 
1034 static void ceph_kill_sb(struct super_block *s)
1035 {
1036 	struct ceph_fs_client *fsc = ceph_sb_to_client(s);
1037 	dev_t dev = s->s_dev;
1038 
1039 	dout("kill_sb %p\n", s);
1040 
1041 	ceph_mdsc_pre_umount(fsc->mdsc);
1042 	generic_shutdown_super(s);
1043 	ceph_mdsc_destroy(fsc);
1044 
1045 	destroy_fs_client(fsc);
1046 	free_anon_bdev(dev);
1047 }
1048 
1049 static struct file_system_type ceph_fs_type = {
1050 	.owner		= THIS_MODULE,
1051 	.name		= "ceph",
1052 	.mount		= ceph_mount,
1053 	.kill_sb	= ceph_kill_sb,
1054 	.fs_flags	= FS_RENAME_DOES_D_MOVE,
1055 };
1056 MODULE_ALIAS_FS("ceph");
1057 
1058 static int __init init_ceph(void)
1059 {
1060 	int ret = init_caches();
1061 	if (ret)
1062 		goto out;
1063 
1064 	ceph_flock_init();
1065 	ceph_xattr_init();
1066 	ret = register_filesystem(&ceph_fs_type);
1067 	if (ret)
1068 		goto out_xattr;
1069 
1070 	pr_info("loaded (mds proto %d)\n", CEPH_MDSC_PROTOCOL);
1071 
1072 	return 0;
1073 
1074 out_xattr:
1075 	ceph_xattr_exit();
1076 	destroy_caches();
1077 out:
1078 	return ret;
1079 }
1080 
1081 static void __exit exit_ceph(void)
1082 {
1083 	dout("exit_ceph\n");
1084 	unregister_filesystem(&ceph_fs_type);
1085 	ceph_xattr_exit();
1086 	destroy_caches();
1087 }
1088 
1089 module_init(init_ceph);
1090 module_exit(exit_ceph);
1091 
1092 MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
1093 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
1094 MODULE_AUTHOR("Patience Warnick <patience@newdream.net>");
1095 MODULE_DESCRIPTION("Ceph filesystem for Linux");
1096 MODULE_LICENSE("GPL");
1097