ceph: fix cap_wanted_delay_{min,max} mount option initialization
[linux-3.10.git] / 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
21 #include <linux/ceph/decode.h>
22 #include <linux/ceph/mon_client.h>
23 #include <linux/ceph/auth.h>
24 #include <linux/ceph/debugfs.h>
25
26 /*
27  * Ceph superblock operations
28  *
29  * Handle the basics of mounting, unmounting.
30  */
31
32 /*
33  * super ops
34  */
35 static void ceph_put_super(struct super_block *s)
36 {
37         struct ceph_fs_client *fsc = ceph_sb_to_client(s);
38
39         dout("put_super\n");
40         ceph_mdsc_close_sessions(fsc->mdsc);
41
42         /*
43          * ensure we release the bdi before put_anon_super releases
44          * the device name.
45          */
46         if (s->s_bdi == &fsc->backing_dev_info) {
47                 bdi_unregister(&fsc->backing_dev_info);
48                 s->s_bdi = NULL;
49         }
50
51         return;
52 }
53
54 static int ceph_statfs(struct dentry *dentry, struct kstatfs *buf)
55 {
56         struct ceph_fs_client *fsc = ceph_inode_to_client(dentry->d_inode);
57         struct ceph_monmap *monmap = fsc->client->monc.monmap;
58         struct ceph_statfs st;
59         u64 fsid;
60         int err;
61
62         dout("statfs\n");
63         err = ceph_monc_do_statfs(&fsc->client->monc, &st);
64         if (err < 0)
65                 return err;
66
67         /* fill in kstatfs */
68         buf->f_type = CEPH_SUPER_MAGIC;  /* ?? */
69
70         /*
71          * express utilization in terms of large blocks to avoid
72          * overflow on 32-bit machines.
73          */
74         buf->f_bsize = 1 << CEPH_BLOCK_SHIFT;
75         buf->f_blocks = le64_to_cpu(st.kb) >> (CEPH_BLOCK_SHIFT-10);
76         buf->f_bfree = (le64_to_cpu(st.kb) - le64_to_cpu(st.kb_used)) >>
77                 (CEPH_BLOCK_SHIFT-10);
78         buf->f_bavail = le64_to_cpu(st.kb_avail) >> (CEPH_BLOCK_SHIFT-10);
79
80         buf->f_files = le64_to_cpu(st.num_objects);
81         buf->f_ffree = -1;
82         buf->f_namelen = NAME_MAX;
83         buf->f_frsize = PAGE_CACHE_SIZE;
84
85         /* leave fsid little-endian, regardless of host endianness */
86         fsid = *(u64 *)(&monmap->fsid) ^ *((u64 *)&monmap->fsid + 1);
87         buf->f_fsid.val[0] = fsid & 0xffffffff;
88         buf->f_fsid.val[1] = fsid >> 32;
89
90         return 0;
91 }
92
93
94 static int ceph_sync_fs(struct super_block *sb, int wait)
95 {
96         struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
97
98         if (!wait) {
99                 dout("sync_fs (non-blocking)\n");
100                 ceph_flush_dirty_caps(fsc->mdsc);
101                 dout("sync_fs (non-blocking) done\n");
102                 return 0;
103         }
104
105         dout("sync_fs (blocking)\n");
106         ceph_osdc_sync(&fsc->client->osdc);
107         ceph_mdsc_sync(fsc->mdsc);
108         dout("sync_fs (blocking) done\n");
109         return 0;
110 }
111
112 /*
113  * mount options
114  */
115 enum {
116         Opt_wsize,
117         Opt_rsize,
118         Opt_caps_wanted_delay_min,
119         Opt_caps_wanted_delay_max,
120         Opt_cap_release_safety,
121         Opt_readdir_max_entries,
122         Opt_readdir_max_bytes,
123         Opt_congestion_kb,
124         Opt_last_int,
125         /* int args above */
126         Opt_snapdirname,
127         Opt_last_string,
128         /* string args above */
129         Opt_dirstat,
130         Opt_nodirstat,
131         Opt_rbytes,
132         Opt_norbytes,
133         Opt_noasyncreaddir,
134 };
135
136 static match_table_t fsopt_tokens = {
137         {Opt_wsize, "wsize=%d"},
138         {Opt_rsize, "rsize=%d"},
139         {Opt_caps_wanted_delay_min, "caps_wanted_delay_min=%d"},
140         {Opt_caps_wanted_delay_max, "caps_wanted_delay_max=%d"},
141         {Opt_cap_release_safety, "cap_release_safety=%d"},
142         {Opt_readdir_max_entries, "readdir_max_entries=%d"},
143         {Opt_readdir_max_bytes, "readdir_max_bytes=%d"},
144         {Opt_congestion_kb, "write_congestion_kb=%d"},
145         /* int args above */
146         {Opt_snapdirname, "snapdirname=%s"},
147         /* string args above */
148         {Opt_dirstat, "dirstat"},
149         {Opt_nodirstat, "nodirstat"},
150         {Opt_rbytes, "rbytes"},
151         {Opt_norbytes, "norbytes"},
152         {Opt_noasyncreaddir, "noasyncreaddir"},
153         {-1, NULL}
154 };
155
156 static int parse_fsopt_token(char *c, void *private)
157 {
158         struct ceph_mount_options *fsopt = private;
159         substring_t argstr[MAX_OPT_ARGS];
160         int token, intval, ret;
161
162         token = match_token((char *)c, fsopt_tokens, argstr);
163         if (token < 0)
164                 return -EINVAL;
165
166         if (token < Opt_last_int) {
167                 ret = match_int(&argstr[0], &intval);
168                 if (ret < 0) {
169                         pr_err("bad mount option arg (not int) "
170                                "at '%s'\n", c);
171                         return ret;
172                 }
173                 dout("got int token %d val %d\n", token, intval);
174         } else if (token > Opt_last_int && token < Opt_last_string) {
175                 dout("got string token %d val %s\n", token,
176                      argstr[0].from);
177         } else {
178                 dout("got token %d\n", token);
179         }
180
181         switch (token) {
182         case Opt_snapdirname:
183                 kfree(fsopt->snapdir_name);
184                 fsopt->snapdir_name = kstrndup(argstr[0].from,
185                                                argstr[0].to-argstr[0].from,
186                                                GFP_KERNEL);
187                 if (!fsopt->snapdir_name)
188                         return -ENOMEM;
189                 break;
190
191                 /* misc */
192         case Opt_wsize:
193                 fsopt->wsize = intval;
194                 break;
195         case Opt_rsize:
196                 fsopt->rsize = intval;
197                 break;
198         case Opt_caps_wanted_delay_min:
199                 fsopt->caps_wanted_delay_min = intval;
200                 break;
201         case Opt_caps_wanted_delay_max:
202                 fsopt->caps_wanted_delay_max = intval;
203                 break;
204         case Opt_readdir_max_entries:
205                 fsopt->max_readdir = intval;
206                 break;
207         case Opt_readdir_max_bytes:
208                 fsopt->max_readdir_bytes = intval;
209                 break;
210         case Opt_congestion_kb:
211                 fsopt->congestion_kb = intval;
212                 break;
213         case Opt_dirstat:
214                 fsopt->flags |= CEPH_MOUNT_OPT_DIRSTAT;
215                 break;
216         case Opt_nodirstat:
217                 fsopt->flags &= ~CEPH_MOUNT_OPT_DIRSTAT;
218                 break;
219         case Opt_rbytes:
220                 fsopt->flags |= CEPH_MOUNT_OPT_RBYTES;
221                 break;
222         case Opt_norbytes:
223                 fsopt->flags &= ~CEPH_MOUNT_OPT_RBYTES;
224                 break;
225         case Opt_noasyncreaddir:
226                 fsopt->flags |= CEPH_MOUNT_OPT_NOASYNCREADDIR;
227                 break;
228         default:
229                 BUG_ON(token);
230         }
231         return 0;
232 }
233
234 static void destroy_mount_options(struct ceph_mount_options *args)
235 {
236         dout("destroy_mount_options %p\n", args);
237         kfree(args->snapdir_name);
238         kfree(args);
239 }
240
241 static int strcmp_null(const char *s1, const char *s2)
242 {
243         if (!s1 && !s2)
244                 return 0;
245         if (s1 && !s2)
246                 return -1;
247         if (!s1 && s2)
248                 return 1;
249         return strcmp(s1, s2);
250 }
251
252 static int compare_mount_options(struct ceph_mount_options *new_fsopt,
253                                  struct ceph_options *new_opt,
254                                  struct ceph_fs_client *fsc)
255 {
256         struct ceph_mount_options *fsopt1 = new_fsopt;
257         struct ceph_mount_options *fsopt2 = fsc->mount_options;
258         int ofs = offsetof(struct ceph_mount_options, snapdir_name);
259         int ret;
260
261         ret = memcmp(fsopt1, fsopt2, ofs);
262         if (ret)
263                 return ret;
264
265         ret = strcmp_null(fsopt1->snapdir_name, fsopt2->snapdir_name);
266         if (ret)
267                 return ret;
268
269         return ceph_compare_options(new_opt, fsc->client);
270 }
271
272 static int parse_mount_options(struct ceph_mount_options **pfsopt,
273                                struct ceph_options **popt,
274                                int flags, char *options,
275                                const char *dev_name,
276                                const char **path)
277 {
278         struct ceph_mount_options *fsopt;
279         const char *dev_name_end;
280         int err = -ENOMEM;
281
282         fsopt = kzalloc(sizeof(*fsopt), GFP_KERNEL);
283         if (!fsopt)
284                 return -ENOMEM;
285
286         dout("parse_mount_options %p, dev_name '%s'\n", fsopt, dev_name);
287
288         fsopt->sb_flags = flags;
289         fsopt->flags = CEPH_MOUNT_OPT_DEFAULT;
290
291         fsopt->rsize = CEPH_MOUNT_RSIZE_DEFAULT;
292         fsopt->snapdir_name = kstrdup(CEPH_SNAPDIRNAME_DEFAULT, GFP_KERNEL);
293         fsopt->caps_wanted_delay_min = CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT;
294         fsopt->caps_wanted_delay_max = CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT;
295         fsopt->cap_release_safety = CEPH_CAP_RELEASE_SAFETY_DEFAULT;
296         fsopt->max_readdir = CEPH_MAX_READDIR_DEFAULT;
297         fsopt->max_readdir_bytes = CEPH_MAX_READDIR_BYTES_DEFAULT;
298         fsopt->congestion_kb = default_congestion_kb();
299         
300         /* ip1[:port1][,ip2[:port2]...]:/subdir/in/fs */
301         err = -EINVAL;
302         if (!dev_name)
303                 goto out;
304         *path = strstr(dev_name, ":/");
305         if (*path == NULL) {
306                 pr_err("device name is missing path (no :/ in %s)\n",
307                        dev_name);
308                 goto out;
309         }
310         dev_name_end = *path;
311         dout("device name '%.*s'\n", (int)(dev_name_end - dev_name), dev_name);
312
313         /* path on server */
314         *path += 2;
315         dout("server path '%s'\n", *path);
316
317         err = ceph_parse_options(popt, options, dev_name, dev_name_end,
318                                  parse_fsopt_token, (void *)fsopt);
319         if (err)
320                 goto out;
321
322         /* success */
323         *pfsopt = fsopt;
324         return 0;
325
326 out:
327         destroy_mount_options(fsopt);
328         return err;
329 }
330
331 /**
332  * ceph_show_options - Show mount options in /proc/mounts
333  * @m: seq_file to write to
334  * @mnt: mount descriptor
335  */
336 static int ceph_show_options(struct seq_file *m, struct vfsmount *mnt)
337 {
338         struct ceph_fs_client *fsc = ceph_sb_to_client(mnt->mnt_sb);
339         struct ceph_mount_options *fsopt = fsc->mount_options;
340         struct ceph_options *opt = fsc->client->options;
341
342         if (opt->flags & CEPH_OPT_FSID)
343                 seq_printf(m, ",fsid=%pU", &opt->fsid);
344         if (opt->flags & CEPH_OPT_NOSHARE)
345                 seq_puts(m, ",noshare");
346         if (opt->flags & CEPH_OPT_NOCRC)
347                 seq_puts(m, ",nocrc");
348
349         if (opt->name)
350                 seq_printf(m, ",name=%s", opt->name);
351         if (opt->secret)
352                 seq_puts(m, ",secret=<hidden>");
353
354         if (opt->mount_timeout != CEPH_MOUNT_TIMEOUT_DEFAULT)
355                 seq_printf(m, ",mount_timeout=%d", opt->mount_timeout);
356         if (opt->osd_idle_ttl != CEPH_OSD_IDLE_TTL_DEFAULT)
357                 seq_printf(m, ",osd_idle_ttl=%d", opt->osd_idle_ttl);
358         if (opt->osd_timeout != CEPH_OSD_TIMEOUT_DEFAULT)
359                 seq_printf(m, ",osdtimeout=%d", opt->osd_timeout);
360         if (opt->osd_keepalive_timeout != CEPH_OSD_KEEPALIVE_DEFAULT)
361                 seq_printf(m, ",osdkeepalivetimeout=%d",
362                            opt->osd_keepalive_timeout);
363
364         if (fsopt->flags & CEPH_MOUNT_OPT_DIRSTAT)
365                 seq_puts(m, ",dirstat");
366         if ((fsopt->flags & CEPH_MOUNT_OPT_RBYTES) == 0)
367                 seq_puts(m, ",norbytes");
368         if (fsopt->flags & CEPH_MOUNT_OPT_NOASYNCREADDIR)
369                 seq_puts(m, ",noasyncreaddir");
370
371         if (fsopt->wsize)
372                 seq_printf(m, ",wsize=%d", fsopt->wsize);
373         if (fsopt->rsize != CEPH_MOUNT_RSIZE_DEFAULT)
374                 seq_printf(m, ",rsize=%d", fsopt->rsize);
375         if (fsopt->congestion_kb != default_congestion_kb())
376                 seq_printf(m, ",write_congestion_kb=%d", fsopt->congestion_kb);
377         if (fsopt->caps_wanted_delay_min != CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT)
378                 seq_printf(m, ",caps_wanted_delay_min=%d",
379                          fsopt->caps_wanted_delay_min);
380         if (fsopt->caps_wanted_delay_max != CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT)
381                 seq_printf(m, ",caps_wanted_delay_max=%d",
382                            fsopt->caps_wanted_delay_max);
383         if (fsopt->cap_release_safety != CEPH_CAP_RELEASE_SAFETY_DEFAULT)
384                 seq_printf(m, ",cap_release_safety=%d",
385                            fsopt->cap_release_safety);
386         if (fsopt->max_readdir != CEPH_MAX_READDIR_DEFAULT)
387                 seq_printf(m, ",readdir_max_entries=%d", fsopt->max_readdir);
388         if (fsopt->max_readdir_bytes != CEPH_MAX_READDIR_BYTES_DEFAULT)
389                 seq_printf(m, ",readdir_max_bytes=%d", fsopt->max_readdir_bytes);
390         if (strcmp(fsopt->snapdir_name, CEPH_SNAPDIRNAME_DEFAULT))
391                 seq_printf(m, ",snapdirname=%s", fsopt->snapdir_name);
392         return 0;
393 }
394
395 /*
396  * handle any mon messages the standard library doesn't understand.
397  * return error if we don't either.
398  */
399 static int extra_mon_dispatch(struct ceph_client *client, struct ceph_msg *msg)
400 {
401         struct ceph_fs_client *fsc = client->private;
402         int type = le16_to_cpu(msg->hdr.type);
403
404         switch (type) {
405         case CEPH_MSG_MDS_MAP:
406                 ceph_mdsc_handle_map(fsc->mdsc, msg);
407                 return 0;
408
409         default:
410                 return -1;
411         }
412 }
413
414 /*
415  * create a new fs client
416  */
417 struct ceph_fs_client *create_fs_client(struct ceph_mount_options *fsopt,
418                                         struct ceph_options *opt)
419 {
420         struct ceph_fs_client *fsc;
421         int err = -ENOMEM;
422
423         fsc = kzalloc(sizeof(*fsc), GFP_KERNEL);
424         if (!fsc)
425                 return ERR_PTR(-ENOMEM);
426
427         fsc->client = ceph_create_client(opt, fsc);
428         if (IS_ERR(fsc->client)) {
429                 err = PTR_ERR(fsc->client);
430                 goto fail;
431         }
432         fsc->client->extra_mon_dispatch = extra_mon_dispatch;
433         fsc->client->supported_features |= CEPH_FEATURE_FLOCK |
434                 CEPH_FEATURE_DIRLAYOUTHASH;
435         fsc->client->monc.want_mdsmap = 1;
436
437         fsc->mount_options = fsopt;
438
439         fsc->sb = NULL;
440         fsc->mount_state = CEPH_MOUNT_MOUNTING;
441
442         atomic_long_set(&fsc->writeback_count, 0);
443
444         err = bdi_init(&fsc->backing_dev_info);
445         if (err < 0)
446                 goto fail_client;
447
448         err = -ENOMEM;
449         /*
450          * The number of concurrent works can be high but they don't need
451          * to be processed in parallel, limit concurrency.
452          */
453         fsc->wb_wq = alloc_workqueue("ceph-writeback", 0, 1);
454         if (fsc->wb_wq == NULL)
455                 goto fail_bdi;
456         fsc->pg_inv_wq = alloc_workqueue("ceph-pg-invalid", 0, 1);
457         if (fsc->pg_inv_wq == NULL)
458                 goto fail_wb_wq;
459         fsc->trunc_wq = alloc_workqueue("ceph-trunc", 0, 1);
460         if (fsc->trunc_wq == NULL)
461                 goto fail_pg_inv_wq;
462
463         /* set up mempools */
464         err = -ENOMEM;
465         fsc->wb_pagevec_pool = mempool_create_kmalloc_pool(10,
466                               fsc->mount_options->wsize >> PAGE_CACHE_SHIFT);
467         if (!fsc->wb_pagevec_pool)
468                 goto fail_trunc_wq;
469
470         /* caps */
471         fsc->min_caps = fsopt->max_readdir;
472
473         return fsc;
474
475 fail_trunc_wq:
476         destroy_workqueue(fsc->trunc_wq);
477 fail_pg_inv_wq:
478         destroy_workqueue(fsc->pg_inv_wq);
479 fail_wb_wq:
480         destroy_workqueue(fsc->wb_wq);
481 fail_bdi:
482         bdi_destroy(&fsc->backing_dev_info);
483 fail_client:
484         ceph_destroy_client(fsc->client);
485 fail:
486         kfree(fsc);
487         return ERR_PTR(err);
488 }
489
490 void destroy_fs_client(struct ceph_fs_client *fsc)
491 {
492         dout("destroy_fs_client %p\n", fsc);
493
494         destroy_workqueue(fsc->wb_wq);
495         destroy_workqueue(fsc->pg_inv_wq);
496         destroy_workqueue(fsc->trunc_wq);
497
498         bdi_destroy(&fsc->backing_dev_info);
499
500         mempool_destroy(fsc->wb_pagevec_pool);
501
502         destroy_mount_options(fsc->mount_options);
503
504         ceph_fs_debugfs_cleanup(fsc);
505
506         ceph_destroy_client(fsc->client);
507
508         kfree(fsc);
509         dout("destroy_fs_client %p done\n", fsc);
510 }
511
512 /*
513  * caches
514  */
515 struct kmem_cache *ceph_inode_cachep;
516 struct kmem_cache *ceph_cap_cachep;
517 struct kmem_cache *ceph_dentry_cachep;
518 struct kmem_cache *ceph_file_cachep;
519
520 static void ceph_inode_init_once(void *foo)
521 {
522         struct ceph_inode_info *ci = foo;
523         inode_init_once(&ci->vfs_inode);
524 }
525
526 static int __init init_caches(void)
527 {
528         ceph_inode_cachep = kmem_cache_create("ceph_inode_info",
529                                       sizeof(struct ceph_inode_info),
530                                       __alignof__(struct ceph_inode_info),
531                                       (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD),
532                                       ceph_inode_init_once);
533         if (ceph_inode_cachep == NULL)
534                 return -ENOMEM;
535
536         ceph_cap_cachep = KMEM_CACHE(ceph_cap,
537                                      SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
538         if (ceph_cap_cachep == NULL)
539                 goto bad_cap;
540
541         ceph_dentry_cachep = KMEM_CACHE(ceph_dentry_info,
542                                         SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
543         if (ceph_dentry_cachep == NULL)
544                 goto bad_dentry;
545
546         ceph_file_cachep = KMEM_CACHE(ceph_file_info,
547                                       SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
548         if (ceph_file_cachep == NULL)
549                 goto bad_file;
550
551         return 0;
552
553 bad_file:
554         kmem_cache_destroy(ceph_dentry_cachep);
555 bad_dentry:
556         kmem_cache_destroy(ceph_cap_cachep);
557 bad_cap:
558         kmem_cache_destroy(ceph_inode_cachep);
559         return -ENOMEM;
560 }
561
562 static void destroy_caches(void)
563 {
564         kmem_cache_destroy(ceph_inode_cachep);
565         kmem_cache_destroy(ceph_cap_cachep);
566         kmem_cache_destroy(ceph_dentry_cachep);
567         kmem_cache_destroy(ceph_file_cachep);
568 }
569
570
571 /*
572  * ceph_umount_begin - initiate forced umount.  Tear down down the
573  * mount, skipping steps that may hang while waiting for server(s).
574  */
575 static void ceph_umount_begin(struct super_block *sb)
576 {
577         struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
578
579         dout("ceph_umount_begin - starting forced umount\n");
580         if (!fsc)
581                 return;
582         fsc->mount_state = CEPH_MOUNT_SHUTDOWN;
583         return;
584 }
585
586 static const struct super_operations ceph_super_ops = {
587         .alloc_inode    = ceph_alloc_inode,
588         .destroy_inode  = ceph_destroy_inode,
589         .write_inode    = ceph_write_inode,
590         .sync_fs        = ceph_sync_fs,
591         .put_super      = ceph_put_super,
592         .show_options   = ceph_show_options,
593         .statfs         = ceph_statfs,
594         .umount_begin   = ceph_umount_begin,
595 };
596
597 /*
598  * Bootstrap mount by opening the root directory.  Note the mount
599  * @started time from caller, and time out if this takes too long.
600  */
601 static struct dentry *open_root_dentry(struct ceph_fs_client *fsc,
602                                        const char *path,
603                                        unsigned long started)
604 {
605         struct ceph_mds_client *mdsc = fsc->mdsc;
606         struct ceph_mds_request *req = NULL;
607         int err;
608         struct dentry *root;
609
610         /* open dir */
611         dout("open_root_inode opening '%s'\n", path);
612         req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_GETATTR, USE_ANY_MDS);
613         if (IS_ERR(req))
614                 return ERR_CAST(req);
615         req->r_path1 = kstrdup(path, GFP_NOFS);
616         req->r_ino1.ino = CEPH_INO_ROOT;
617         req->r_ino1.snap = CEPH_NOSNAP;
618         req->r_started = started;
619         req->r_timeout = fsc->client->options->mount_timeout * HZ;
620         req->r_args.getattr.mask = cpu_to_le32(CEPH_STAT_CAP_INODE);
621         req->r_num_caps = 2;
622         err = ceph_mdsc_do_request(mdsc, NULL, req);
623         if (err == 0) {
624                 dout("open_root_inode success\n");
625                 if (ceph_ino(req->r_target_inode) == CEPH_INO_ROOT &&
626                     fsc->sb->s_root == NULL)
627                         root = d_alloc_root(req->r_target_inode);
628                 else
629                         root = d_obtain_alias(req->r_target_inode);
630                 req->r_target_inode = NULL;
631                 dout("open_root_inode success, root dentry is %p\n", root);
632         } else {
633                 root = ERR_PTR(err);
634         }
635         ceph_mdsc_put_request(req);
636         return root;
637 }
638
639
640
641
642 /*
643  * mount: join the ceph cluster, and open root directory.
644  */
645 static struct dentry *ceph_real_mount(struct ceph_fs_client *fsc,
646                       const char *path)
647 {
648         int err;
649         unsigned long started = jiffies;  /* note the start time */
650         struct dentry *root;
651         int first = 0;   /* first vfsmount for this super_block */
652
653         dout("mount start\n");
654         mutex_lock(&fsc->client->mount_mutex);
655
656         err = __ceph_open_session(fsc->client, started);
657         if (err < 0)
658                 goto out;
659
660         dout("mount opening root\n");
661         root = open_root_dentry(fsc, "", started);
662         if (IS_ERR(root)) {
663                 err = PTR_ERR(root);
664                 goto out;
665         }
666         if (fsc->sb->s_root) {
667                 dput(root);
668         } else {
669                 fsc->sb->s_root = root;
670                 first = 1;
671
672                 err = ceph_fs_debugfs_init(fsc);
673                 if (err < 0)
674                         goto fail;
675         }
676
677         if (path[0] == 0) {
678                 dget(root);
679         } else {
680                 dout("mount opening base mountpoint\n");
681                 root = open_root_dentry(fsc, path, started);
682                 if (IS_ERR(root)) {
683                         err = PTR_ERR(root);
684                         goto fail;
685                 }
686         }
687
688         fsc->mount_state = CEPH_MOUNT_MOUNTED;
689         dout("mount success\n");
690         mutex_unlock(&fsc->client->mount_mutex);
691         return root;
692
693 out:
694         mutex_unlock(&fsc->client->mount_mutex);
695         return ERR_PTR(err);
696
697 fail:
698         if (first) {
699                 dput(fsc->sb->s_root);
700                 fsc->sb->s_root = NULL;
701         }
702         goto out;
703 }
704
705 static int ceph_set_super(struct super_block *s, void *data)
706 {
707         struct ceph_fs_client *fsc = data;
708         int ret;
709
710         dout("set_super %p data %p\n", s, data);
711
712         s->s_flags = fsc->mount_options->sb_flags;
713         s->s_maxbytes = 1ULL << 40;  /* temp value until we get mdsmap */
714
715         s->s_fs_info = fsc;
716         fsc->sb = s;
717
718         s->s_op = &ceph_super_ops;
719         s->s_export_op = &ceph_export_ops;
720
721         s->s_time_gran = 1000;  /* 1000 ns == 1 us */
722
723         ret = set_anon_super(s, NULL);  /* what is that second arg for? */
724         if (ret != 0)
725                 goto fail;
726
727         return ret;
728
729 fail:
730         s->s_fs_info = NULL;
731         fsc->sb = NULL;
732         return ret;
733 }
734
735 /*
736  * share superblock if same fs AND options
737  */
738 static int ceph_compare_super(struct super_block *sb, void *data)
739 {
740         struct ceph_fs_client *new = data;
741         struct ceph_mount_options *fsopt = new->mount_options;
742         struct ceph_options *opt = new->client->options;
743         struct ceph_fs_client *other = ceph_sb_to_client(sb);
744
745         dout("ceph_compare_super %p\n", sb);
746
747         if (compare_mount_options(fsopt, opt, other)) {
748                 dout("monitor(s)/mount options don't match\n");
749                 return 0;
750         }
751         if ((opt->flags & CEPH_OPT_FSID) &&
752             ceph_fsid_compare(&opt->fsid, &other->client->fsid)) {
753                 dout("fsid doesn't match\n");
754                 return 0;
755         }
756         if (fsopt->sb_flags != other->mount_options->sb_flags) {
757                 dout("flags differ\n");
758                 return 0;
759         }
760         return 1;
761 }
762
763 /*
764  * construct our own bdi so we can control readahead, etc.
765  */
766 static atomic_long_t bdi_seq = ATOMIC_LONG_INIT(0);
767
768 static int ceph_register_bdi(struct super_block *sb,
769                              struct ceph_fs_client *fsc)
770 {
771         int err;
772
773         /* set ra_pages based on rsize mount option? */
774         if (fsc->mount_options->rsize >= PAGE_CACHE_SIZE)
775                 fsc->backing_dev_info.ra_pages =
776                         (fsc->mount_options->rsize + PAGE_CACHE_SIZE - 1)
777                         >> PAGE_SHIFT;
778         err = bdi_register(&fsc->backing_dev_info, NULL, "ceph-%d",
779                            atomic_long_inc_return(&bdi_seq));
780         if (!err)
781                 sb->s_bdi = &fsc->backing_dev_info;
782         return err;
783 }
784
785 static struct dentry *ceph_mount(struct file_system_type *fs_type,
786                        int flags, const char *dev_name, void *data)
787 {
788         struct super_block *sb;
789         struct ceph_fs_client *fsc;
790         struct dentry *res;
791         int err;
792         int (*compare_super)(struct super_block *, void *) = ceph_compare_super;
793         const char *path = NULL;
794         struct ceph_mount_options *fsopt = NULL;
795         struct ceph_options *opt = NULL;
796
797         dout("ceph_mount\n");
798         err = parse_mount_options(&fsopt, &opt, flags, data, dev_name, &path);
799         if (err < 0) {
800                 res = ERR_PTR(err);
801                 goto out_final;
802         }
803
804         /* create client (which we may/may not use) */
805         fsc = create_fs_client(fsopt, opt);
806         if (IS_ERR(fsc)) {
807                 res = ERR_CAST(fsc);
808                 kfree(fsopt);
809                 kfree(opt);
810                 goto out_final;
811         }
812
813         err = ceph_mdsc_init(fsc);
814         if (err < 0) {
815                 res = ERR_PTR(err);
816                 goto out;
817         }
818
819         if (ceph_test_opt(fsc->client, NOSHARE))
820                 compare_super = NULL;
821         sb = sget(fs_type, compare_super, ceph_set_super, fsc);
822         if (IS_ERR(sb)) {
823                 res = ERR_CAST(sb);
824                 goto out;
825         }
826
827         if (ceph_sb_to_client(sb) != fsc) {
828                 ceph_mdsc_destroy(fsc);
829                 destroy_fs_client(fsc);
830                 fsc = ceph_sb_to_client(sb);
831                 dout("get_sb got existing client %p\n", fsc);
832         } else {
833                 dout("get_sb using new client %p\n", fsc);
834                 err = ceph_register_bdi(sb, fsc);
835                 if (err < 0) {
836                         res = ERR_PTR(err);
837                         goto out_splat;
838                 }
839         }
840
841         res = ceph_real_mount(fsc, path);
842         if (IS_ERR(res))
843                 goto out_splat;
844         dout("root %p inode %p ino %llx.%llx\n", res,
845              res->d_inode, ceph_vinop(res->d_inode));
846         return res;
847
848 out_splat:
849         ceph_mdsc_close_sessions(fsc->mdsc);
850         deactivate_locked_super(sb);
851         goto out_final;
852
853 out:
854         ceph_mdsc_destroy(fsc);
855         destroy_fs_client(fsc);
856 out_final:
857         dout("ceph_mount fail %ld\n", PTR_ERR(res));
858         return res;
859 }
860
861 static void ceph_kill_sb(struct super_block *s)
862 {
863         struct ceph_fs_client *fsc = ceph_sb_to_client(s);
864         dout("kill_sb %p\n", s);
865         ceph_mdsc_pre_umount(fsc->mdsc);
866         kill_anon_super(s);    /* will call put_super after sb is r/o */
867         ceph_mdsc_destroy(fsc);
868         destroy_fs_client(fsc);
869 }
870
871 static struct file_system_type ceph_fs_type = {
872         .owner          = THIS_MODULE,
873         .name           = "ceph",
874         .mount          = ceph_mount,
875         .kill_sb        = ceph_kill_sb,
876         .fs_flags       = FS_RENAME_DOES_D_MOVE,
877 };
878
879 #define _STRINGIFY(x) #x
880 #define STRINGIFY(x) _STRINGIFY(x)
881
882 static int __init init_ceph(void)
883 {
884         int ret = init_caches();
885         if (ret)
886                 goto out;
887
888         ret = register_filesystem(&ceph_fs_type);
889         if (ret)
890                 goto out_icache;
891
892         pr_info("loaded (mds proto %d)\n", CEPH_MDSC_PROTOCOL);
893
894         return 0;
895
896 out_icache:
897         destroy_caches();
898 out:
899         return ret;
900 }
901
902 static void __exit exit_ceph(void)
903 {
904         dout("exit_ceph\n");
905         unregister_filesystem(&ceph_fs_type);
906         destroy_caches();
907 }
908
909 module_init(init_ceph);
910 module_exit(exit_ceph);
911
912 MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
913 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
914 MODULE_AUTHOR("Patience Warnick <patience@newdream.net>");
915 MODULE_DESCRIPTION("Ceph filesystem for Linux");
916 MODULE_LICENSE("GPL");