These changes are a raw update to a vanilla kernel 4.1.10, with the
[kvmfornfv.git] / kernel / fs / ceph / super.c
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_last_string,
124         /* string args above */
125         Opt_dirstat,
126         Opt_nodirstat,
127         Opt_rbytes,
128         Opt_norbytes,
129         Opt_asyncreaddir,
130         Opt_noasyncreaddir,
131         Opt_dcache,
132         Opt_nodcache,
133         Opt_ino32,
134         Opt_noino32,
135         Opt_fscache,
136         Opt_nofscache,
137 #ifdef CONFIG_CEPH_FS_POSIX_ACL
138         Opt_acl,
139 #endif
140         Opt_noacl
141 };
142
143 static match_table_t fsopt_tokens = {
144         {Opt_wsize, "wsize=%d"},
145         {Opt_rsize, "rsize=%d"},
146         {Opt_rasize, "rasize=%d"},
147         {Opt_caps_wanted_delay_min, "caps_wanted_delay_min=%d"},
148         {Opt_caps_wanted_delay_max, "caps_wanted_delay_max=%d"},
149         {Opt_cap_release_safety, "cap_release_safety=%d"},
150         {Opt_readdir_max_entries, "readdir_max_entries=%d"},
151         {Opt_readdir_max_bytes, "readdir_max_bytes=%d"},
152         {Opt_congestion_kb, "write_congestion_kb=%d"},
153         /* int args above */
154         {Opt_snapdirname, "snapdirname=%s"},
155         /* string args above */
156         {Opt_dirstat, "dirstat"},
157         {Opt_nodirstat, "nodirstat"},
158         {Opt_rbytes, "rbytes"},
159         {Opt_norbytes, "norbytes"},
160         {Opt_asyncreaddir, "asyncreaddir"},
161         {Opt_noasyncreaddir, "noasyncreaddir"},
162         {Opt_dcache, "dcache"},
163         {Opt_nodcache, "nodcache"},
164         {Opt_ino32, "ino32"},
165         {Opt_noino32, "noino32"},
166         {Opt_fscache, "fsc"},
167         {Opt_nofscache, "nofsc"},
168 #ifdef CONFIG_CEPH_FS_POSIX_ACL
169         {Opt_acl, "acl"},
170 #endif
171         {Opt_noacl, "noacl"},
172         {-1, NULL}
173 };
174
175 static int parse_fsopt_token(char *c, void *private)
176 {
177         struct ceph_mount_options *fsopt = private;
178         substring_t argstr[MAX_OPT_ARGS];
179         int token, intval, ret;
180
181         token = match_token((char *)c, fsopt_tokens, argstr);
182         if (token < 0)
183                 return -EINVAL;
184
185         if (token < Opt_last_int) {
186                 ret = match_int(&argstr[0], &intval);
187                 if (ret < 0) {
188                         pr_err("bad mount option arg (not int) "
189                                "at '%s'\n", c);
190                         return ret;
191                 }
192                 dout("got int token %d val %d\n", token, intval);
193         } else if (token > Opt_last_int && token < Opt_last_string) {
194                 dout("got string token %d val %s\n", token,
195                      argstr[0].from);
196         } else {
197                 dout("got token %d\n", token);
198         }
199
200         switch (token) {
201         case Opt_snapdirname:
202                 kfree(fsopt->snapdir_name);
203                 fsopt->snapdir_name = kstrndup(argstr[0].from,
204                                                argstr[0].to-argstr[0].from,
205                                                GFP_KERNEL);
206                 if (!fsopt->snapdir_name)
207                         return -ENOMEM;
208                 break;
209
210                 /* misc */
211         case Opt_wsize:
212                 fsopt->wsize = intval;
213                 break;
214         case Opt_rsize:
215                 fsopt->rsize = intval;
216                 break;
217         case Opt_rasize:
218                 fsopt->rasize = intval;
219                 break;
220         case Opt_caps_wanted_delay_min:
221                 fsopt->caps_wanted_delay_min = intval;
222                 break;
223         case Opt_caps_wanted_delay_max:
224                 fsopt->caps_wanted_delay_max = intval;
225                 break;
226         case Opt_readdir_max_entries:
227                 fsopt->max_readdir = intval;
228                 break;
229         case Opt_readdir_max_bytes:
230                 fsopt->max_readdir_bytes = intval;
231                 break;
232         case Opt_congestion_kb:
233                 fsopt->congestion_kb = intval;
234                 break;
235         case Opt_dirstat:
236                 fsopt->flags |= CEPH_MOUNT_OPT_DIRSTAT;
237                 break;
238         case Opt_nodirstat:
239                 fsopt->flags &= ~CEPH_MOUNT_OPT_DIRSTAT;
240                 break;
241         case Opt_rbytes:
242                 fsopt->flags |= CEPH_MOUNT_OPT_RBYTES;
243                 break;
244         case Opt_norbytes:
245                 fsopt->flags &= ~CEPH_MOUNT_OPT_RBYTES;
246                 break;
247         case Opt_asyncreaddir:
248                 fsopt->flags &= ~CEPH_MOUNT_OPT_NOASYNCREADDIR;
249                 break;
250         case Opt_noasyncreaddir:
251                 fsopt->flags |= CEPH_MOUNT_OPT_NOASYNCREADDIR;
252                 break;
253         case Opt_dcache:
254                 fsopt->flags |= CEPH_MOUNT_OPT_DCACHE;
255                 break;
256         case Opt_nodcache:
257                 fsopt->flags &= ~CEPH_MOUNT_OPT_DCACHE;
258                 break;
259         case Opt_ino32:
260                 fsopt->flags |= CEPH_MOUNT_OPT_INO32;
261                 break;
262         case Opt_noino32:
263                 fsopt->flags &= ~CEPH_MOUNT_OPT_INO32;
264                 break;
265         case Opt_fscache:
266                 fsopt->flags |= CEPH_MOUNT_OPT_FSCACHE;
267                 break;
268         case Opt_nofscache:
269                 fsopt->flags &= ~CEPH_MOUNT_OPT_FSCACHE;
270                 break;
271 #ifdef CONFIG_CEPH_FS_POSIX_ACL
272         case Opt_acl:
273                 fsopt->sb_flags |= MS_POSIXACL;
274                 break;
275 #endif
276         case Opt_noacl:
277                 fsopt->sb_flags &= ~MS_POSIXACL;
278                 break;
279         default:
280                 BUG_ON(token);
281         }
282         return 0;
283 }
284
285 static void destroy_mount_options(struct ceph_mount_options *args)
286 {
287         dout("destroy_mount_options %p\n", args);
288         kfree(args->snapdir_name);
289         kfree(args);
290 }
291
292 static int strcmp_null(const char *s1, const char *s2)
293 {
294         if (!s1 && !s2)
295                 return 0;
296         if (s1 && !s2)
297                 return -1;
298         if (!s1 && s2)
299                 return 1;
300         return strcmp(s1, s2);
301 }
302
303 static int compare_mount_options(struct ceph_mount_options *new_fsopt,
304                                  struct ceph_options *new_opt,
305                                  struct ceph_fs_client *fsc)
306 {
307         struct ceph_mount_options *fsopt1 = new_fsopt;
308         struct ceph_mount_options *fsopt2 = fsc->mount_options;
309         int ofs = offsetof(struct ceph_mount_options, snapdir_name);
310         int ret;
311
312         ret = memcmp(fsopt1, fsopt2, ofs);
313         if (ret)
314                 return ret;
315
316         ret = strcmp_null(fsopt1->snapdir_name, fsopt2->snapdir_name);
317         if (ret)
318                 return ret;
319
320         return ceph_compare_options(new_opt, fsc->client);
321 }
322
323 static int parse_mount_options(struct ceph_mount_options **pfsopt,
324                                struct ceph_options **popt,
325                                int flags, char *options,
326                                const char *dev_name,
327                                const char **path)
328 {
329         struct ceph_mount_options *fsopt;
330         const char *dev_name_end;
331         int err;
332
333         if (!dev_name || !*dev_name)
334                 return -EINVAL;
335
336         fsopt = kzalloc(sizeof(*fsopt), GFP_KERNEL);
337         if (!fsopt)
338                 return -ENOMEM;
339
340         dout("parse_mount_options %p, dev_name '%s'\n", fsopt, dev_name);
341
342         fsopt->sb_flags = flags;
343         fsopt->flags = CEPH_MOUNT_OPT_DEFAULT;
344
345         fsopt->rsize = CEPH_RSIZE_DEFAULT;
346         fsopt->rasize = CEPH_RASIZE_DEFAULT;
347         fsopt->snapdir_name = kstrdup(CEPH_SNAPDIRNAME_DEFAULT, GFP_KERNEL);
348         if (!fsopt->snapdir_name) {
349                 err = -ENOMEM;
350                 goto out;
351         }
352
353         fsopt->caps_wanted_delay_min = CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT;
354         fsopt->caps_wanted_delay_max = CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT;
355         fsopt->cap_release_safety = CEPH_CAP_RELEASE_SAFETY_DEFAULT;
356         fsopt->max_readdir = CEPH_MAX_READDIR_DEFAULT;
357         fsopt->max_readdir_bytes = CEPH_MAX_READDIR_BYTES_DEFAULT;
358         fsopt->congestion_kb = default_congestion_kb();
359
360         /*
361          * Distinguish the server list from the path in "dev_name".
362          * Internally we do not include the leading '/' in the path.
363          *
364          * "dev_name" will look like:
365          *     <server_spec>[,<server_spec>...]:[<path>]
366          * where
367          *     <server_spec> is <ip>[:<port>]
368          *     <path> is optional, but if present must begin with '/'
369          */
370         dev_name_end = strchr(dev_name, '/');
371         if (dev_name_end) {
372                 /* skip over leading '/' for path */
373                 *path = dev_name_end + 1;
374         } else {
375                 /* path is empty */
376                 dev_name_end = dev_name + strlen(dev_name);
377                 *path = dev_name_end;
378         }
379         err = -EINVAL;
380         dev_name_end--;         /* back up to ':' separator */
381         if (dev_name_end < dev_name || *dev_name_end != ':') {
382                 pr_err("device name is missing path (no : separator in %s)\n",
383                                 dev_name);
384                 goto out;
385         }
386         dout("device name '%.*s'\n", (int)(dev_name_end - dev_name), dev_name);
387         dout("server path '%s'\n", *path);
388
389         *popt = ceph_parse_options(options, dev_name, dev_name_end,
390                                  parse_fsopt_token, (void *)fsopt);
391         if (IS_ERR(*popt)) {
392                 err = PTR_ERR(*popt);
393                 goto out;
394         }
395
396         /* success */
397         *pfsopt = fsopt;
398         return 0;
399
400 out:
401         destroy_mount_options(fsopt);
402         return err;
403 }
404
405 /**
406  * ceph_show_options - Show mount options in /proc/mounts
407  * @m: seq_file to write to
408  * @root: root of that (sub)tree
409  */
410 static int ceph_show_options(struct seq_file *m, struct dentry *root)
411 {
412         struct ceph_fs_client *fsc = ceph_sb_to_client(root->d_sb);
413         struct ceph_mount_options *fsopt = fsc->mount_options;
414         size_t pos;
415         int ret;
416
417         /* a comma between MNT/MS and client options */
418         seq_putc(m, ',');
419         pos = m->count;
420
421         ret = ceph_print_client_options(m, fsc->client);
422         if (ret)
423                 return ret;
424
425         /* retract our comma if no client options */
426         if (m->count == pos)
427                 m->count--;
428
429         if (fsopt->flags & CEPH_MOUNT_OPT_DIRSTAT)
430                 seq_puts(m, ",dirstat");
431         if ((fsopt->flags & CEPH_MOUNT_OPT_RBYTES) == 0)
432                 seq_puts(m, ",norbytes");
433         if (fsopt->flags & CEPH_MOUNT_OPT_NOASYNCREADDIR)
434                 seq_puts(m, ",noasyncreaddir");
435         if ((fsopt->flags & CEPH_MOUNT_OPT_DCACHE) == 0)
436                 seq_puts(m, ",nodcache");
437         if (fsopt->flags & CEPH_MOUNT_OPT_FSCACHE)
438                 seq_puts(m, ",fsc");
439
440 #ifdef CONFIG_CEPH_FS_POSIX_ACL
441         if (fsopt->sb_flags & MS_POSIXACL)
442                 seq_puts(m, ",acl");
443         else
444                 seq_puts(m, ",noacl");
445 #endif
446
447         if (fsopt->wsize)
448                 seq_printf(m, ",wsize=%d", fsopt->wsize);
449         if (fsopt->rsize != CEPH_RSIZE_DEFAULT)
450                 seq_printf(m, ",rsize=%d", fsopt->rsize);
451         if (fsopt->rasize != CEPH_RASIZE_DEFAULT)
452                 seq_printf(m, ",rasize=%d", fsopt->rasize);
453         if (fsopt->congestion_kb != default_congestion_kb())
454                 seq_printf(m, ",write_congestion_kb=%d", fsopt->congestion_kb);
455         if (fsopt->caps_wanted_delay_min != CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT)
456                 seq_printf(m, ",caps_wanted_delay_min=%d",
457                          fsopt->caps_wanted_delay_min);
458         if (fsopt->caps_wanted_delay_max != CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT)
459                 seq_printf(m, ",caps_wanted_delay_max=%d",
460                            fsopt->caps_wanted_delay_max);
461         if (fsopt->cap_release_safety != CEPH_CAP_RELEASE_SAFETY_DEFAULT)
462                 seq_printf(m, ",cap_release_safety=%d",
463                            fsopt->cap_release_safety);
464         if (fsopt->max_readdir != CEPH_MAX_READDIR_DEFAULT)
465                 seq_printf(m, ",readdir_max_entries=%d", fsopt->max_readdir);
466         if (fsopt->max_readdir_bytes != CEPH_MAX_READDIR_BYTES_DEFAULT)
467                 seq_printf(m, ",readdir_max_bytes=%d", fsopt->max_readdir_bytes);
468         if (strcmp(fsopt->snapdir_name, CEPH_SNAPDIRNAME_DEFAULT))
469                 seq_show_option(m, "snapdirname", fsopt->snapdir_name);
470
471         return 0;
472 }
473
474 /*
475  * handle any mon messages the standard library doesn't understand.
476  * return error if we don't either.
477  */
478 static int extra_mon_dispatch(struct ceph_client *client, struct ceph_msg *msg)
479 {
480         struct ceph_fs_client *fsc = client->private;
481         int type = le16_to_cpu(msg->hdr.type);
482
483         switch (type) {
484         case CEPH_MSG_MDS_MAP:
485                 ceph_mdsc_handle_map(fsc->mdsc, msg);
486                 return 0;
487
488         default:
489                 return -1;
490         }
491 }
492
493 /*
494  * create a new fs client
495  */
496 static struct ceph_fs_client *create_fs_client(struct ceph_mount_options *fsopt,
497                                         struct ceph_options *opt)
498 {
499         struct ceph_fs_client *fsc;
500         const u64 supported_features =
501                 CEPH_FEATURE_FLOCK |
502                 CEPH_FEATURE_DIRLAYOUTHASH |
503                 CEPH_FEATURE_MDS_INLINE_DATA;
504         const u64 required_features = 0;
505         int page_count;
506         size_t size;
507         int err = -ENOMEM;
508
509         fsc = kzalloc(sizeof(*fsc), GFP_KERNEL);
510         if (!fsc)
511                 return ERR_PTR(-ENOMEM);
512
513         fsc->client = ceph_create_client(opt, fsc, supported_features,
514                                          required_features);
515         if (IS_ERR(fsc->client)) {
516                 err = PTR_ERR(fsc->client);
517                 goto fail;
518         }
519         fsc->client->extra_mon_dispatch = extra_mon_dispatch;
520         fsc->client->monc.want_mdsmap = 1;
521
522         fsc->mount_options = fsopt;
523
524         fsc->sb = NULL;
525         fsc->mount_state = CEPH_MOUNT_MOUNTING;
526
527         atomic_long_set(&fsc->writeback_count, 0);
528
529         err = bdi_init(&fsc->backing_dev_info);
530         if (err < 0)
531                 goto fail_client;
532
533         err = -ENOMEM;
534         /*
535          * The number of concurrent works can be high but they don't need
536          * to be processed in parallel, limit concurrency.
537          */
538         fsc->wb_wq = alloc_workqueue("ceph-writeback", 0, 1);
539         if (fsc->wb_wq == NULL)
540                 goto fail_bdi;
541         fsc->pg_inv_wq = alloc_workqueue("ceph-pg-invalid", 0, 1);
542         if (fsc->pg_inv_wq == NULL)
543                 goto fail_wb_wq;
544         fsc->trunc_wq = alloc_workqueue("ceph-trunc", 0, 1);
545         if (fsc->trunc_wq == NULL)
546                 goto fail_pg_inv_wq;
547
548         /* set up mempools */
549         err = -ENOMEM;
550         page_count = fsc->mount_options->wsize >> PAGE_CACHE_SHIFT;
551         size = sizeof (struct page *) * (page_count ? page_count : 1);
552         fsc->wb_pagevec_pool = mempool_create_kmalloc_pool(10, size);
553         if (!fsc->wb_pagevec_pool)
554                 goto fail_trunc_wq;
555
556         /* setup fscache */
557         if ((fsopt->flags & CEPH_MOUNT_OPT_FSCACHE) &&
558             (ceph_fscache_register_fs(fsc) != 0))
559                 goto fail_fscache;
560
561         /* caps */
562         fsc->min_caps = fsopt->max_readdir;
563
564         return fsc;
565
566 fail_fscache:
567         ceph_fscache_unregister_fs(fsc);
568 fail_trunc_wq:
569         destroy_workqueue(fsc->trunc_wq);
570 fail_pg_inv_wq:
571         destroy_workqueue(fsc->pg_inv_wq);
572 fail_wb_wq:
573         destroy_workqueue(fsc->wb_wq);
574 fail_bdi:
575         bdi_destroy(&fsc->backing_dev_info);
576 fail_client:
577         ceph_destroy_client(fsc->client);
578 fail:
579         kfree(fsc);
580         return ERR_PTR(err);
581 }
582
583 static void destroy_fs_client(struct ceph_fs_client *fsc)
584 {
585         dout("destroy_fs_client %p\n", fsc);
586
587         ceph_fscache_unregister_fs(fsc);
588
589         destroy_workqueue(fsc->wb_wq);
590         destroy_workqueue(fsc->pg_inv_wq);
591         destroy_workqueue(fsc->trunc_wq);
592
593         bdi_destroy(&fsc->backing_dev_info);
594
595         mempool_destroy(fsc->wb_pagevec_pool);
596
597         destroy_mount_options(fsc->mount_options);
598
599         ceph_fs_debugfs_cleanup(fsc);
600
601         ceph_destroy_client(fsc->client);
602
603         kfree(fsc);
604         dout("destroy_fs_client %p done\n", fsc);
605 }
606
607 /*
608  * caches
609  */
610 struct kmem_cache *ceph_inode_cachep;
611 struct kmem_cache *ceph_cap_cachep;
612 struct kmem_cache *ceph_dentry_cachep;
613 struct kmem_cache *ceph_file_cachep;
614
615 static void ceph_inode_init_once(void *foo)
616 {
617         struct ceph_inode_info *ci = foo;
618         inode_init_once(&ci->vfs_inode);
619 }
620
621 static int __init init_caches(void)
622 {
623         int error = -ENOMEM;
624
625         ceph_inode_cachep = kmem_cache_create("ceph_inode_info",
626                                       sizeof(struct ceph_inode_info),
627                                       __alignof__(struct ceph_inode_info),
628                                       (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD),
629                                       ceph_inode_init_once);
630         if (ceph_inode_cachep == NULL)
631                 return -ENOMEM;
632
633         ceph_cap_cachep = KMEM_CACHE(ceph_cap,
634                                      SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
635         if (ceph_cap_cachep == NULL)
636                 goto bad_cap;
637
638         ceph_dentry_cachep = KMEM_CACHE(ceph_dentry_info,
639                                         SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
640         if (ceph_dentry_cachep == NULL)
641                 goto bad_dentry;
642
643         ceph_file_cachep = KMEM_CACHE(ceph_file_info,
644                                       SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
645         if (ceph_file_cachep == NULL)
646                 goto bad_file;
647
648         if ((error = ceph_fscache_register()))
649                 goto bad_file;
650
651         return 0;
652 bad_file:
653         kmem_cache_destroy(ceph_dentry_cachep);
654 bad_dentry:
655         kmem_cache_destroy(ceph_cap_cachep);
656 bad_cap:
657         kmem_cache_destroy(ceph_inode_cachep);
658         return error;
659 }
660
661 static void destroy_caches(void)
662 {
663         /*
664          * Make sure all delayed rcu free inodes are flushed before we
665          * destroy cache.
666          */
667         rcu_barrier();
668
669         kmem_cache_destroy(ceph_inode_cachep);
670         kmem_cache_destroy(ceph_cap_cachep);
671         kmem_cache_destroy(ceph_dentry_cachep);
672         kmem_cache_destroy(ceph_file_cachep);
673
674         ceph_fscache_unregister();
675 }
676
677
678 /*
679  * ceph_umount_begin - initiate forced umount.  Tear down down the
680  * mount, skipping steps that may hang while waiting for server(s).
681  */
682 static void ceph_umount_begin(struct super_block *sb)
683 {
684         struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
685
686         dout("ceph_umount_begin - starting forced umount\n");
687         if (!fsc)
688                 return;
689         fsc->mount_state = CEPH_MOUNT_SHUTDOWN;
690         return;
691 }
692
693 static const struct super_operations ceph_super_ops = {
694         .alloc_inode    = ceph_alloc_inode,
695         .destroy_inode  = ceph_destroy_inode,
696         .write_inode    = ceph_write_inode,
697         .drop_inode     = ceph_drop_inode,
698         .sync_fs        = ceph_sync_fs,
699         .put_super      = ceph_put_super,
700         .show_options   = ceph_show_options,
701         .statfs         = ceph_statfs,
702         .umount_begin   = ceph_umount_begin,
703 };
704
705 /*
706  * Bootstrap mount by opening the root directory.  Note the mount
707  * @started time from caller, and time out if this takes too long.
708  */
709 static struct dentry *open_root_dentry(struct ceph_fs_client *fsc,
710                                        const char *path,
711                                        unsigned long started)
712 {
713         struct ceph_mds_client *mdsc = fsc->mdsc;
714         struct ceph_mds_request *req = NULL;
715         int err;
716         struct dentry *root;
717
718         /* open dir */
719         dout("open_root_inode opening '%s'\n", path);
720         req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_GETATTR, USE_ANY_MDS);
721         if (IS_ERR(req))
722                 return ERR_CAST(req);
723         req->r_path1 = kstrdup(path, GFP_NOFS);
724         if (!req->r_path1) {
725                 root = ERR_PTR(-ENOMEM);
726                 goto out;
727         }
728
729         req->r_ino1.ino = CEPH_INO_ROOT;
730         req->r_ino1.snap = CEPH_NOSNAP;
731         req->r_started = started;
732         req->r_timeout = fsc->client->options->mount_timeout * HZ;
733         req->r_args.getattr.mask = cpu_to_le32(CEPH_STAT_CAP_INODE);
734         req->r_num_caps = 2;
735         err = ceph_mdsc_do_request(mdsc, NULL, req);
736         if (err == 0) {
737                 struct inode *inode = req->r_target_inode;
738                 req->r_target_inode = NULL;
739                 dout("open_root_inode success\n");
740                 if (ceph_ino(inode) == CEPH_INO_ROOT &&
741                     fsc->sb->s_root == NULL) {
742                         root = d_make_root(inode);
743                         if (!root) {
744                                 root = ERR_PTR(-ENOMEM);
745                                 goto out;
746                         }
747                 } else {
748                         root = d_obtain_root(inode);
749                 }
750                 ceph_init_dentry(root);
751                 dout("open_root_inode success, root dentry is %p\n", root);
752         } else {
753                 root = ERR_PTR(err);
754         }
755 out:
756         ceph_mdsc_put_request(req);
757         return root;
758 }
759
760
761
762
763 /*
764  * mount: join the ceph cluster, and open root directory.
765  */
766 static struct dentry *ceph_real_mount(struct ceph_fs_client *fsc,
767                       const char *path)
768 {
769         int err;
770         unsigned long started = jiffies;  /* note the start time */
771         struct dentry *root;
772         int first = 0;   /* first vfsmount for this super_block */
773
774         dout("mount start\n");
775         mutex_lock(&fsc->client->mount_mutex);
776
777         err = __ceph_open_session(fsc->client, started);
778         if (err < 0)
779                 goto out;
780
781         dout("mount opening root\n");
782         root = open_root_dentry(fsc, "", started);
783         if (IS_ERR(root)) {
784                 err = PTR_ERR(root);
785                 goto out;
786         }
787         if (fsc->sb->s_root) {
788                 dput(root);
789         } else {
790                 fsc->sb->s_root = root;
791                 first = 1;
792
793                 err = ceph_fs_debugfs_init(fsc);
794                 if (err < 0)
795                         goto fail;
796         }
797
798         if (path[0] == 0) {
799                 dget(root);
800         } else {
801                 dout("mount opening base mountpoint\n");
802                 root = open_root_dentry(fsc, path, started);
803                 if (IS_ERR(root)) {
804                         err = PTR_ERR(root);
805                         goto fail;
806                 }
807         }
808
809         fsc->mount_state = CEPH_MOUNT_MOUNTED;
810         dout("mount success\n");
811         mutex_unlock(&fsc->client->mount_mutex);
812         return root;
813
814 out:
815         mutex_unlock(&fsc->client->mount_mutex);
816         return ERR_PTR(err);
817
818 fail:
819         if (first) {
820                 dput(fsc->sb->s_root);
821                 fsc->sb->s_root = NULL;
822         }
823         goto out;
824 }
825
826 static int ceph_set_super(struct super_block *s, void *data)
827 {
828         struct ceph_fs_client *fsc = data;
829         int ret;
830
831         dout("set_super %p data %p\n", s, data);
832
833         s->s_flags = fsc->mount_options->sb_flags;
834         s->s_maxbytes = 1ULL << 40;  /* temp value until we get mdsmap */
835
836         s->s_xattr = ceph_xattr_handlers;
837         s->s_fs_info = fsc;
838         fsc->sb = s;
839
840         s->s_op = &ceph_super_ops;
841         s->s_export_op = &ceph_export_ops;
842
843         s->s_time_gran = 1000;  /* 1000 ns == 1 us */
844
845         ret = set_anon_super(s, NULL);  /* what is that second arg for? */
846         if (ret != 0)
847                 goto fail;
848
849         return ret;
850
851 fail:
852         s->s_fs_info = NULL;
853         fsc->sb = NULL;
854         return ret;
855 }
856
857 /*
858  * share superblock if same fs AND options
859  */
860 static int ceph_compare_super(struct super_block *sb, void *data)
861 {
862         struct ceph_fs_client *new = data;
863         struct ceph_mount_options *fsopt = new->mount_options;
864         struct ceph_options *opt = new->client->options;
865         struct ceph_fs_client *other = ceph_sb_to_client(sb);
866
867         dout("ceph_compare_super %p\n", sb);
868
869         if (compare_mount_options(fsopt, opt, other)) {
870                 dout("monitor(s)/mount options don't match\n");
871                 return 0;
872         }
873         if ((opt->flags & CEPH_OPT_FSID) &&
874             ceph_fsid_compare(&opt->fsid, &other->client->fsid)) {
875                 dout("fsid doesn't match\n");
876                 return 0;
877         }
878         if (fsopt->sb_flags != other->mount_options->sb_flags) {
879                 dout("flags differ\n");
880                 return 0;
881         }
882         return 1;
883 }
884
885 /*
886  * construct our own bdi so we can control readahead, etc.
887  */
888 static atomic_long_t bdi_seq = ATOMIC_LONG_INIT(0);
889
890 static int ceph_register_bdi(struct super_block *sb,
891                              struct ceph_fs_client *fsc)
892 {
893         int err;
894
895         /* set ra_pages based on rasize mount option? */
896         if (fsc->mount_options->rasize >= PAGE_CACHE_SIZE)
897                 fsc->backing_dev_info.ra_pages =
898                         (fsc->mount_options->rasize + PAGE_CACHE_SIZE - 1)
899                         >> PAGE_SHIFT;
900         else
901                 fsc->backing_dev_info.ra_pages =
902                         VM_MAX_READAHEAD * 1024 / PAGE_CACHE_SIZE;
903
904         err = bdi_register(&fsc->backing_dev_info, NULL, "ceph-%ld",
905                            atomic_long_inc_return(&bdi_seq));
906         if (!err)
907                 sb->s_bdi = &fsc->backing_dev_info;
908         return err;
909 }
910
911 static struct dentry *ceph_mount(struct file_system_type *fs_type,
912                        int flags, const char *dev_name, void *data)
913 {
914         struct super_block *sb;
915         struct ceph_fs_client *fsc;
916         struct dentry *res;
917         int err;
918         int (*compare_super)(struct super_block *, void *) = ceph_compare_super;
919         const char *path = NULL;
920         struct ceph_mount_options *fsopt = NULL;
921         struct ceph_options *opt = NULL;
922
923         dout("ceph_mount\n");
924
925 #ifdef CONFIG_CEPH_FS_POSIX_ACL
926         flags |= MS_POSIXACL;
927 #endif
928         err = parse_mount_options(&fsopt, &opt, flags, data, dev_name, &path);
929         if (err < 0) {
930                 res = ERR_PTR(err);
931                 goto out_final;
932         }
933
934         /* create client (which we may/may not use) */
935         fsc = create_fs_client(fsopt, opt);
936         if (IS_ERR(fsc)) {
937                 res = ERR_CAST(fsc);
938                 destroy_mount_options(fsopt);
939                 ceph_destroy_options(opt);
940                 goto out_final;
941         }
942
943         err = ceph_mdsc_init(fsc);
944         if (err < 0) {
945                 res = ERR_PTR(err);
946                 goto out;
947         }
948
949         if (ceph_test_opt(fsc->client, NOSHARE))
950                 compare_super = NULL;
951         sb = sget(fs_type, compare_super, ceph_set_super, flags, fsc);
952         if (IS_ERR(sb)) {
953                 res = ERR_CAST(sb);
954                 goto out;
955         }
956
957         if (ceph_sb_to_client(sb) != fsc) {
958                 ceph_mdsc_destroy(fsc);
959                 destroy_fs_client(fsc);
960                 fsc = ceph_sb_to_client(sb);
961                 dout("get_sb got existing client %p\n", fsc);
962         } else {
963                 dout("get_sb using new client %p\n", fsc);
964                 err = ceph_register_bdi(sb, fsc);
965                 if (err < 0) {
966                         res = ERR_PTR(err);
967                         goto out_splat;
968                 }
969         }
970
971         res = ceph_real_mount(fsc, path);
972         if (IS_ERR(res))
973                 goto out_splat;
974         dout("root %p inode %p ino %llx.%llx\n", res,
975              d_inode(res), ceph_vinop(d_inode(res)));
976         return res;
977
978 out_splat:
979         ceph_mdsc_close_sessions(fsc->mdsc);
980         deactivate_locked_super(sb);
981         goto out_final;
982
983 out:
984         ceph_mdsc_destroy(fsc);
985         destroy_fs_client(fsc);
986 out_final:
987         dout("ceph_mount fail %ld\n", PTR_ERR(res));
988         return res;
989 }
990
991 static void ceph_kill_sb(struct super_block *s)
992 {
993         struct ceph_fs_client *fsc = ceph_sb_to_client(s);
994         dev_t dev = s->s_dev;
995
996         dout("kill_sb %p\n", s);
997
998         ceph_mdsc_pre_umount(fsc->mdsc);
999         generic_shutdown_super(s);
1000         ceph_mdsc_destroy(fsc);
1001
1002         destroy_fs_client(fsc);
1003         free_anon_bdev(dev);
1004 }
1005
1006 static struct file_system_type ceph_fs_type = {
1007         .owner          = THIS_MODULE,
1008         .name           = "ceph",
1009         .mount          = ceph_mount,
1010         .kill_sb        = ceph_kill_sb,
1011         .fs_flags       = FS_RENAME_DOES_D_MOVE,
1012 };
1013 MODULE_ALIAS_FS("ceph");
1014
1015 static int __init init_ceph(void)
1016 {
1017         int ret = init_caches();
1018         if (ret)
1019                 goto out;
1020
1021         ceph_flock_init();
1022         ceph_xattr_init();
1023         ret = ceph_snap_init();
1024         if (ret)
1025                 goto out_xattr;
1026         ret = register_filesystem(&ceph_fs_type);
1027         if (ret)
1028                 goto out_snap;
1029
1030         pr_info("loaded (mds proto %d)\n", CEPH_MDSC_PROTOCOL);
1031
1032         return 0;
1033
1034 out_snap:
1035         ceph_snap_exit();
1036 out_xattr:
1037         ceph_xattr_exit();
1038         destroy_caches();
1039 out:
1040         return ret;
1041 }
1042
1043 static void __exit exit_ceph(void)
1044 {
1045         dout("exit_ceph\n");
1046         unregister_filesystem(&ceph_fs_type);
1047         ceph_snap_exit();
1048         ceph_xattr_exit();
1049         destroy_caches();
1050 }
1051
1052 module_init(init_ceph);
1053 module_exit(exit_ceph);
1054
1055 MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
1056 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
1057 MODULE_AUTHOR("Patience Warnick <patience@newdream.net>");
1058 MODULE_DESCRIPTION("Ceph filesystem for Linux");
1059 MODULE_LICENSE("GPL");