Merge branch 'for-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
[linux-3.10.git] / fs / gfs2 / super.c
1 /*
2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
3  * Copyright (C) 2004-2007 Red Hat, Inc.  All rights reserved.
4  *
5  * This copyrighted material is made available to anyone wishing to use,
6  * modify, copy, or redistribute it subject to the terms and conditions
7  * of the GNU General Public License version 2.
8  */
9
10 #include <linux/bio.h>
11 #include <linux/sched.h>
12 #include <linux/slab.h>
13 #include <linux/spinlock.h>
14 #include <linux/completion.h>
15 #include <linux/buffer_head.h>
16 #include <linux/statfs.h>
17 #include <linux/seq_file.h>
18 #include <linux/mount.h>
19 #include <linux/kthread.h>
20 #include <linux/delay.h>
21 #include <linux/gfs2_ondisk.h>
22 #include <linux/crc32.h>
23 #include <linux/time.h>
24 #include <linux/wait.h>
25 #include <linux/writeback.h>
26 #include <linux/backing-dev.h>
27
28 #include "gfs2.h"
29 #include "incore.h"
30 #include "bmap.h"
31 #include "dir.h"
32 #include "glock.h"
33 #include "glops.h"
34 #include "inode.h"
35 #include "log.h"
36 #include "meta_io.h"
37 #include "quota.h"
38 #include "recovery.h"
39 #include "rgrp.h"
40 #include "super.h"
41 #include "trans.h"
42 #include "util.h"
43 #include "sys.h"
44 #include "xattr.h"
45
46 #define args_neq(a1, a2, x) ((a1)->ar_##x != (a2)->ar_##x)
47
48 enum {
49         Opt_lockproto,
50         Opt_locktable,
51         Opt_hostdata,
52         Opt_spectator,
53         Opt_ignore_local_fs,
54         Opt_localflocks,
55         Opt_localcaching,
56         Opt_debug,
57         Opt_nodebug,
58         Opt_upgrade,
59         Opt_acl,
60         Opt_noacl,
61         Opt_quota_off,
62         Opt_quota_account,
63         Opt_quota_on,
64         Opt_quota,
65         Opt_noquota,
66         Opt_suiddir,
67         Opt_nosuiddir,
68         Opt_data_writeback,
69         Opt_data_ordered,
70         Opt_meta,
71         Opt_discard,
72         Opt_nodiscard,
73         Opt_commit,
74         Opt_err_withdraw,
75         Opt_err_panic,
76         Opt_statfs_quantum,
77         Opt_statfs_percent,
78         Opt_quota_quantum,
79         Opt_barrier,
80         Opt_nobarrier,
81         Opt_rgrplvb,
82         Opt_norgrplvb,
83         Opt_error,
84 };
85
86 static const match_table_t tokens = {
87         {Opt_lockproto, "lockproto=%s"},
88         {Opt_locktable, "locktable=%s"},
89         {Opt_hostdata, "hostdata=%s"},
90         {Opt_spectator, "spectator"},
91         {Opt_spectator, "norecovery"},
92         {Opt_ignore_local_fs, "ignore_local_fs"},
93         {Opt_localflocks, "localflocks"},
94         {Opt_localcaching, "localcaching"},
95         {Opt_debug, "debug"},
96         {Opt_nodebug, "nodebug"},
97         {Opt_upgrade, "upgrade"},
98         {Opt_acl, "acl"},
99         {Opt_noacl, "noacl"},
100         {Opt_quota_off, "quota=off"},
101         {Opt_quota_account, "quota=account"},
102         {Opt_quota_on, "quota=on"},
103         {Opt_quota, "quota"},
104         {Opt_noquota, "noquota"},
105         {Opt_suiddir, "suiddir"},
106         {Opt_nosuiddir, "nosuiddir"},
107         {Opt_data_writeback, "data=writeback"},
108         {Opt_data_ordered, "data=ordered"},
109         {Opt_meta, "meta"},
110         {Opt_discard, "discard"},
111         {Opt_nodiscard, "nodiscard"},
112         {Opt_commit, "commit=%d"},
113         {Opt_err_withdraw, "errors=withdraw"},
114         {Opt_err_panic, "errors=panic"},
115         {Opt_statfs_quantum, "statfs_quantum=%d"},
116         {Opt_statfs_percent, "statfs_percent=%d"},
117         {Opt_quota_quantum, "quota_quantum=%d"},
118         {Opt_barrier, "barrier"},
119         {Opt_nobarrier, "nobarrier"},
120         {Opt_rgrplvb, "rgrplvb"},
121         {Opt_norgrplvb, "norgrplvb"},
122         {Opt_error, NULL}
123 };
124
125 /**
126  * gfs2_mount_args - Parse mount options
127  * @args: The structure into which the parsed options will be written
128  * @options: The options to parse
129  *
130  * Return: errno
131  */
132
133 int gfs2_mount_args(struct gfs2_args *args, char *options)
134 {
135         char *o;
136         int token;
137         substring_t tmp[MAX_OPT_ARGS];
138         int rv;
139
140         /* Split the options into tokens with the "," character and
141            process them */
142
143         while (1) {
144                 o = strsep(&options, ",");
145                 if (o == NULL)
146                         break;
147                 if (*o == '\0')
148                         continue;
149
150                 token = match_token(o, tokens, tmp);
151                 switch (token) {
152                 case Opt_lockproto:
153                         match_strlcpy(args->ar_lockproto, &tmp[0],
154                                       GFS2_LOCKNAME_LEN);
155                         break;
156                 case Opt_locktable:
157                         match_strlcpy(args->ar_locktable, &tmp[0],
158                                       GFS2_LOCKNAME_LEN);
159                         break;
160                 case Opt_hostdata:
161                         match_strlcpy(args->ar_hostdata, &tmp[0],
162                                       GFS2_LOCKNAME_LEN);
163                         break;
164                 case Opt_spectator:
165                         args->ar_spectator = 1;
166                         break;
167                 case Opt_ignore_local_fs:
168                         /* Retained for backwards compat only */
169                         break;
170                 case Opt_localflocks:
171                         args->ar_localflocks = 1;
172                         break;
173                 case Opt_localcaching:
174                         /* Retained for backwards compat only */
175                         break;
176                 case Opt_debug:
177                         if (args->ar_errors == GFS2_ERRORS_PANIC) {
178                                 printk(KERN_WARNING "GFS2: -o debug and -o errors=panic "
179                                        "are mutually exclusive.\n");
180                                 return -EINVAL;
181                         }
182                         args->ar_debug = 1;
183                         break;
184                 case Opt_nodebug:
185                         args->ar_debug = 0;
186                         break;
187                 case Opt_upgrade:
188                         /* Retained for backwards compat only */
189                         break;
190                 case Opt_acl:
191                         args->ar_posix_acl = 1;
192                         break;
193                 case Opt_noacl:
194                         args->ar_posix_acl = 0;
195                         break;
196                 case Opt_quota_off:
197                 case Opt_noquota:
198                         args->ar_quota = GFS2_QUOTA_OFF;
199                         break;
200                 case Opt_quota_account:
201                         args->ar_quota = GFS2_QUOTA_ACCOUNT;
202                         break;
203                 case Opt_quota_on:
204                 case Opt_quota:
205                         args->ar_quota = GFS2_QUOTA_ON;
206                         break;
207                 case Opt_suiddir:
208                         args->ar_suiddir = 1;
209                         break;
210                 case Opt_nosuiddir:
211                         args->ar_suiddir = 0;
212                         break;
213                 case Opt_data_writeback:
214                         args->ar_data = GFS2_DATA_WRITEBACK;
215                         break;
216                 case Opt_data_ordered:
217                         args->ar_data = GFS2_DATA_ORDERED;
218                         break;
219                 case Opt_meta:
220                         args->ar_meta = 1;
221                         break;
222                 case Opt_discard:
223                         args->ar_discard = 1;
224                         break;
225                 case Opt_nodiscard:
226                         args->ar_discard = 0;
227                         break;
228                 case Opt_commit:
229                         rv = match_int(&tmp[0], &args->ar_commit);
230                         if (rv || args->ar_commit <= 0) {
231                                 printk(KERN_WARNING "GFS2: commit mount option requires a positive numeric argument\n");
232                                 return rv ? rv : -EINVAL;
233                         }
234                         break;
235                 case Opt_statfs_quantum:
236                         rv = match_int(&tmp[0], &args->ar_statfs_quantum);
237                         if (rv || args->ar_statfs_quantum < 0) {
238                                 printk(KERN_WARNING "GFS2: statfs_quantum mount option requires a non-negative numeric argument\n");
239                                 return rv ? rv : -EINVAL;
240                         }
241                         break;
242                 case Opt_quota_quantum:
243                         rv = match_int(&tmp[0], &args->ar_quota_quantum);
244                         if (rv || args->ar_quota_quantum <= 0) {
245                                 printk(KERN_WARNING "GFS2: quota_quantum mount option requires a positive numeric argument\n");
246                                 return rv ? rv : -EINVAL;
247                         }
248                         break;
249                 case Opt_statfs_percent:
250                         rv = match_int(&tmp[0], &args->ar_statfs_percent);
251                         if (rv || args->ar_statfs_percent < 0 ||
252                             args->ar_statfs_percent > 100) {
253                                 printk(KERN_WARNING "statfs_percent mount option requires a numeric argument between 0 and 100\n");
254                                 return rv ? rv : -EINVAL;
255                         }
256                         break;
257                 case Opt_err_withdraw:
258                         args->ar_errors = GFS2_ERRORS_WITHDRAW;
259                         break;
260                 case Opt_err_panic:
261                         if (args->ar_debug) {
262                                 printk(KERN_WARNING "GFS2: -o debug and -o errors=panic "
263                                         "are mutually exclusive.\n");
264                                 return -EINVAL;
265                         }
266                         args->ar_errors = GFS2_ERRORS_PANIC;
267                         break;
268                 case Opt_barrier:
269                         args->ar_nobarrier = 0;
270                         break;
271                 case Opt_nobarrier:
272                         args->ar_nobarrier = 1;
273                         break;
274                 case Opt_rgrplvb:
275                         args->ar_rgrplvb = 1;
276                         break;
277                 case Opt_norgrplvb:
278                         args->ar_rgrplvb = 0;
279                         break;
280                 case Opt_error:
281                 default:
282                         printk(KERN_WARNING "GFS2: invalid mount option: %s\n", o);
283                         return -EINVAL;
284                 }
285         }
286
287         return 0;
288 }
289
290 /**
291  * gfs2_jindex_free - Clear all the journal index information
292  * @sdp: The GFS2 superblock
293  *
294  */
295
296 void gfs2_jindex_free(struct gfs2_sbd *sdp)
297 {
298         struct list_head list, *head;
299         struct gfs2_jdesc *jd;
300         struct gfs2_journal_extent *jext;
301
302         spin_lock(&sdp->sd_jindex_spin);
303         list_add(&list, &sdp->sd_jindex_list);
304         list_del_init(&sdp->sd_jindex_list);
305         sdp->sd_journals = 0;
306         spin_unlock(&sdp->sd_jindex_spin);
307
308         while (!list_empty(&list)) {
309                 jd = list_entry(list.next, struct gfs2_jdesc, jd_list);
310                 head = &jd->extent_list;
311                 while (!list_empty(head)) {
312                         jext = list_entry(head->next,
313                                           struct gfs2_journal_extent,
314                                           extent_list);
315                         list_del(&jext->extent_list);
316                         kfree(jext);
317                 }
318                 list_del(&jd->jd_list);
319                 iput(jd->jd_inode);
320                 kfree(jd);
321         }
322 }
323
324 static struct gfs2_jdesc *jdesc_find_i(struct list_head *head, unsigned int jid)
325 {
326         struct gfs2_jdesc *jd;
327         int found = 0;
328
329         list_for_each_entry(jd, head, jd_list) {
330                 if (jd->jd_jid == jid) {
331                         found = 1;
332                         break;
333                 }
334         }
335
336         if (!found)
337                 jd = NULL;
338
339         return jd;
340 }
341
342 struct gfs2_jdesc *gfs2_jdesc_find(struct gfs2_sbd *sdp, unsigned int jid)
343 {
344         struct gfs2_jdesc *jd;
345
346         spin_lock(&sdp->sd_jindex_spin);
347         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
348         spin_unlock(&sdp->sd_jindex_spin);
349
350         return jd;
351 }
352
353 int gfs2_jdesc_check(struct gfs2_jdesc *jd)
354 {
355         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
356         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
357         u64 size = i_size_read(jd->jd_inode);
358
359         if (gfs2_check_internal_file_size(jd->jd_inode, 8 << 20, 1 << 30))
360                 return -EIO;
361
362         jd->jd_blocks = size >> sdp->sd_sb.sb_bsize_shift;
363
364         if (gfs2_write_alloc_required(ip, 0, size)) {
365                 gfs2_consist_inode(ip);
366                 return -EIO;
367         }
368
369         return 0;
370 }
371
372 /**
373  * gfs2_make_fs_rw - Turn a Read-Only FS into a Read-Write one
374  * @sdp: the filesystem
375  *
376  * Returns: errno
377  */
378
379 int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
380 {
381         struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
382         struct gfs2_glock *j_gl = ip->i_gl;
383         struct gfs2_holder t_gh;
384         struct gfs2_log_header_host head;
385         int error;
386
387         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED, 0, &t_gh);
388         if (error)
389                 return error;
390
391         j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
392
393         error = gfs2_find_jhead(sdp->sd_jdesc, &head);
394         if (error)
395                 goto fail;
396
397         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
398                 gfs2_consist(sdp);
399                 error = -EIO;
400                 goto fail;
401         }
402
403         /*  Initialize some head of the log stuff  */
404         sdp->sd_log_sequence = head.lh_sequence + 1;
405         gfs2_log_pointers_init(sdp, head.lh_blkno);
406
407         error = gfs2_quota_init(sdp);
408         if (error)
409                 goto fail;
410
411         set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
412
413         gfs2_glock_dq_uninit(&t_gh);
414
415         return 0;
416
417 fail:
418         t_gh.gh_flags |= GL_NOCACHE;
419         gfs2_glock_dq_uninit(&t_gh);
420
421         return error;
422 }
423
424 void gfs2_statfs_change_in(struct gfs2_statfs_change_host *sc, const void *buf)
425 {
426         const struct gfs2_statfs_change *str = buf;
427
428         sc->sc_total = be64_to_cpu(str->sc_total);
429         sc->sc_free = be64_to_cpu(str->sc_free);
430         sc->sc_dinodes = be64_to_cpu(str->sc_dinodes);
431 }
432
433 static void gfs2_statfs_change_out(const struct gfs2_statfs_change_host *sc, void *buf)
434 {
435         struct gfs2_statfs_change *str = buf;
436
437         str->sc_total = cpu_to_be64(sc->sc_total);
438         str->sc_free = cpu_to_be64(sc->sc_free);
439         str->sc_dinodes = cpu_to_be64(sc->sc_dinodes);
440 }
441
442 int gfs2_statfs_init(struct gfs2_sbd *sdp)
443 {
444         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
445         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
446         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
447         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
448         struct buffer_head *m_bh, *l_bh;
449         struct gfs2_holder gh;
450         int error;
451
452         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
453                                    &gh);
454         if (error)
455                 return error;
456
457         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
458         if (error)
459                 goto out;
460
461         if (sdp->sd_args.ar_spectator) {
462                 spin_lock(&sdp->sd_statfs_spin);
463                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
464                                       sizeof(struct gfs2_dinode));
465                 spin_unlock(&sdp->sd_statfs_spin);
466         } else {
467                 error = gfs2_meta_inode_buffer(l_ip, &l_bh);
468                 if (error)
469                         goto out_m_bh;
470
471                 spin_lock(&sdp->sd_statfs_spin);
472                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
473                                       sizeof(struct gfs2_dinode));
474                 gfs2_statfs_change_in(l_sc, l_bh->b_data +
475                                       sizeof(struct gfs2_dinode));
476                 spin_unlock(&sdp->sd_statfs_spin);
477
478                 brelse(l_bh);
479         }
480
481 out_m_bh:
482         brelse(m_bh);
483 out:
484         gfs2_glock_dq_uninit(&gh);
485         return 0;
486 }
487
488 void gfs2_statfs_change(struct gfs2_sbd *sdp, s64 total, s64 free,
489                         s64 dinodes)
490 {
491         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
492         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
493         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
494         struct buffer_head *l_bh;
495         s64 x, y;
496         int need_sync = 0;
497         int error;
498
499         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
500         if (error)
501                 return;
502
503         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
504
505         spin_lock(&sdp->sd_statfs_spin);
506         l_sc->sc_total += total;
507         l_sc->sc_free += free;
508         l_sc->sc_dinodes += dinodes;
509         gfs2_statfs_change_out(l_sc, l_bh->b_data + sizeof(struct gfs2_dinode));
510         if (sdp->sd_args.ar_statfs_percent) {
511                 x = 100 * l_sc->sc_free;
512                 y = m_sc->sc_free * sdp->sd_args.ar_statfs_percent;
513                 if (x >= y || x <= -y)
514                         need_sync = 1;
515         }
516         spin_unlock(&sdp->sd_statfs_spin);
517
518         brelse(l_bh);
519         if (need_sync)
520                 gfs2_wake_up_statfs(sdp);
521 }
522
523 void update_statfs(struct gfs2_sbd *sdp, struct buffer_head *m_bh,
524                    struct buffer_head *l_bh)
525 {
526         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
527         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
528         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
529         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
530
531         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
532
533         spin_lock(&sdp->sd_statfs_spin);
534         m_sc->sc_total += l_sc->sc_total;
535         m_sc->sc_free += l_sc->sc_free;
536         m_sc->sc_dinodes += l_sc->sc_dinodes;
537         memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
538         memset(l_bh->b_data + sizeof(struct gfs2_dinode),
539                0, sizeof(struct gfs2_statfs_change));
540         spin_unlock(&sdp->sd_statfs_spin);
541
542         gfs2_trans_add_bh(m_ip->i_gl, m_bh, 1);
543         gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
544 }
545
546 int gfs2_statfs_sync(struct super_block *sb, int type)
547 {
548         struct gfs2_sbd *sdp = sb->s_fs_info;
549         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
550         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
551         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
552         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
553         struct gfs2_holder gh;
554         struct buffer_head *m_bh, *l_bh;
555         int error;
556
557         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
558                                    &gh);
559         if (error)
560                 return error;
561
562         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
563         if (error)
564                 goto out;
565
566         spin_lock(&sdp->sd_statfs_spin);
567         gfs2_statfs_change_in(m_sc, m_bh->b_data +
568                               sizeof(struct gfs2_dinode));
569         if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
570                 spin_unlock(&sdp->sd_statfs_spin);
571                 goto out_bh;
572         }
573         spin_unlock(&sdp->sd_statfs_spin);
574
575         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
576         if (error)
577                 goto out_bh;
578
579         error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
580         if (error)
581                 goto out_bh2;
582
583         update_statfs(sdp, m_bh, l_bh);
584         sdp->sd_statfs_force_sync = 0;
585
586         gfs2_trans_end(sdp);
587
588 out_bh2:
589         brelse(l_bh);
590 out_bh:
591         brelse(m_bh);
592 out:
593         gfs2_glock_dq_uninit(&gh);
594         return error;
595 }
596
597 struct lfcc {
598         struct list_head list;
599         struct gfs2_holder gh;
600 };
601
602 /**
603  * gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
604  *                            journals are clean
605  * @sdp: the file system
606  * @state: the state to put the transaction lock into
607  * @t_gh: the hold on the transaction lock
608  *
609  * Returns: errno
610  */
611
612 static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp,
613                                     struct gfs2_holder *t_gh)
614 {
615         struct gfs2_inode *ip;
616         struct gfs2_jdesc *jd;
617         struct lfcc *lfcc;
618         LIST_HEAD(list);
619         struct gfs2_log_header_host lh;
620         int error;
621
622         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
623                 lfcc = kmalloc(sizeof(struct lfcc), GFP_KERNEL);
624                 if (!lfcc) {
625                         error = -ENOMEM;
626                         goto out;
627                 }
628                 ip = GFS2_I(jd->jd_inode);
629                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &lfcc->gh);
630                 if (error) {
631                         kfree(lfcc);
632                         goto out;
633                 }
634                 list_add(&lfcc->list, &list);
635         }
636
637         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_DEFERRED,
638                                    GL_NOCACHE, t_gh);
639
640         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
641                 error = gfs2_jdesc_check(jd);
642                 if (error)
643                         break;
644                 error = gfs2_find_jhead(jd, &lh);
645                 if (error)
646                         break;
647                 if (!(lh.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
648                         error = -EBUSY;
649                         break;
650                 }
651         }
652
653         if (error)
654                 gfs2_glock_dq_uninit(t_gh);
655
656 out:
657         while (!list_empty(&list)) {
658                 lfcc = list_entry(list.next, struct lfcc, list);
659                 list_del(&lfcc->list);
660                 gfs2_glock_dq_uninit(&lfcc->gh);
661                 kfree(lfcc);
662         }
663         return error;
664 }
665
666 /**
667  * gfs2_freeze_fs - freezes the file system
668  * @sdp: the file system
669  *
670  * This function flushes data and meta data for all machines by
671  * acquiring the transaction log exclusively.  All journals are
672  * ensured to be in a clean state as well.
673  *
674  * Returns: errno
675  */
676
677 int gfs2_freeze_fs(struct gfs2_sbd *sdp)
678 {
679         int error = 0;
680
681         mutex_lock(&sdp->sd_freeze_lock);
682
683         if (!sdp->sd_freeze_count++) {
684                 error = gfs2_lock_fs_check_clean(sdp, &sdp->sd_freeze_gh);
685                 if (error)
686                         sdp->sd_freeze_count--;
687         }
688
689         mutex_unlock(&sdp->sd_freeze_lock);
690
691         return error;
692 }
693
694 /**
695  * gfs2_unfreeze_fs - unfreezes the file system
696  * @sdp: the file system
697  *
698  * This function allows the file system to proceed by unlocking
699  * the exclusively held transaction lock.  Other GFS2 nodes are
700  * now free to acquire the lock shared and go on with their lives.
701  *
702  */
703
704 void gfs2_unfreeze_fs(struct gfs2_sbd *sdp)
705 {
706         mutex_lock(&sdp->sd_freeze_lock);
707
708         if (sdp->sd_freeze_count && !--sdp->sd_freeze_count)
709                 gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
710
711         mutex_unlock(&sdp->sd_freeze_lock);
712 }
713
714 void gfs2_dinode_out(const struct gfs2_inode *ip, void *buf)
715 {
716         struct gfs2_dinode *str = buf;
717
718         str->di_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
719         str->di_header.mh_type = cpu_to_be32(GFS2_METATYPE_DI);
720         str->di_header.mh_format = cpu_to_be32(GFS2_FORMAT_DI);
721         str->di_num.no_addr = cpu_to_be64(ip->i_no_addr);
722         str->di_num.no_formal_ino = cpu_to_be64(ip->i_no_formal_ino);
723         str->di_mode = cpu_to_be32(ip->i_inode.i_mode);
724         str->di_uid = cpu_to_be32(ip->i_inode.i_uid);
725         str->di_gid = cpu_to_be32(ip->i_inode.i_gid);
726         str->di_nlink = cpu_to_be32(ip->i_inode.i_nlink);
727         str->di_size = cpu_to_be64(i_size_read(&ip->i_inode));
728         str->di_blocks = cpu_to_be64(gfs2_get_inode_blocks(&ip->i_inode));
729         str->di_atime = cpu_to_be64(ip->i_inode.i_atime.tv_sec);
730         str->di_mtime = cpu_to_be64(ip->i_inode.i_mtime.tv_sec);
731         str->di_ctime = cpu_to_be64(ip->i_inode.i_ctime.tv_sec);
732
733         str->di_goal_meta = cpu_to_be64(ip->i_goal);
734         str->di_goal_data = cpu_to_be64(ip->i_goal);
735         str->di_generation = cpu_to_be64(ip->i_generation);
736
737         str->di_flags = cpu_to_be32(ip->i_diskflags);
738         str->di_height = cpu_to_be16(ip->i_height);
739         str->di_payload_format = cpu_to_be32(S_ISDIR(ip->i_inode.i_mode) &&
740                                              !(ip->i_diskflags & GFS2_DIF_EXHASH) ?
741                                              GFS2_FORMAT_DE : 0);
742         str->di_depth = cpu_to_be16(ip->i_depth);
743         str->di_entries = cpu_to_be32(ip->i_entries);
744
745         str->di_eattr = cpu_to_be64(ip->i_eattr);
746         str->di_atime_nsec = cpu_to_be32(ip->i_inode.i_atime.tv_nsec);
747         str->di_mtime_nsec = cpu_to_be32(ip->i_inode.i_mtime.tv_nsec);
748         str->di_ctime_nsec = cpu_to_be32(ip->i_inode.i_ctime.tv_nsec);
749 }
750
751 /**
752  * gfs2_write_inode - Make sure the inode is stable on the disk
753  * @inode: The inode
754  * @wbc: The writeback control structure
755  *
756  * Returns: errno
757  */
758
759 static int gfs2_write_inode(struct inode *inode, struct writeback_control *wbc)
760 {
761         struct gfs2_inode *ip = GFS2_I(inode);
762         struct gfs2_sbd *sdp = GFS2_SB(inode);
763         struct address_space *metamapping = gfs2_glock2aspace(ip->i_gl);
764         struct backing_dev_info *bdi = metamapping->backing_dev_info;
765         int ret = 0;
766
767         if (wbc->sync_mode == WB_SYNC_ALL)
768                 gfs2_log_flush(GFS2_SB(inode), ip->i_gl);
769         if (bdi->dirty_exceeded)
770                 gfs2_ail1_flush(sdp, wbc);
771         else
772                 filemap_fdatawrite(metamapping);
773         if (wbc->sync_mode == WB_SYNC_ALL)
774                 ret = filemap_fdatawait(metamapping);
775         if (ret)
776                 mark_inode_dirty_sync(inode);
777         return ret;
778 }
779
780 /**
781  * gfs2_dirty_inode - check for atime updates
782  * @inode: The inode in question
783  * @flags: The type of dirty
784  *
785  * Unfortunately it can be called under any combination of inode
786  * glock and transaction lock, so we have to check carefully.
787  *
788  * At the moment this deals only with atime - it should be possible
789  * to expand that role in future, once a review of the locking has
790  * been carried out.
791  */
792
793 static void gfs2_dirty_inode(struct inode *inode, int flags)
794 {
795         struct gfs2_inode *ip = GFS2_I(inode);
796         struct gfs2_sbd *sdp = GFS2_SB(inode);
797         struct buffer_head *bh;
798         struct gfs2_holder gh;
799         int need_unlock = 0;
800         int need_endtrans = 0;
801         int ret;
802
803         if (!(flags & (I_DIRTY_DATASYNC|I_DIRTY_SYNC)))
804                 return;
805
806         if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
807                 ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
808                 if (ret) {
809                         fs_err(sdp, "dirty_inode: glock %d\n", ret);
810                         return;
811                 }
812                 need_unlock = 1;
813         }
814
815         if (current->journal_info == NULL) {
816                 ret = gfs2_trans_begin(sdp, RES_DINODE, 0);
817                 if (ret) {
818                         fs_err(sdp, "dirty_inode: gfs2_trans_begin %d\n", ret);
819                         goto out;
820                 }
821                 need_endtrans = 1;
822         }
823
824         ret = gfs2_meta_inode_buffer(ip, &bh);
825         if (ret == 0) {
826                 gfs2_trans_add_bh(ip->i_gl, bh, 1);
827                 gfs2_dinode_out(ip, bh->b_data);
828                 brelse(bh);
829         }
830
831         if (need_endtrans)
832                 gfs2_trans_end(sdp);
833 out:
834         if (need_unlock)
835                 gfs2_glock_dq_uninit(&gh);
836 }
837
838 /**
839  * gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
840  * @sdp: the filesystem
841  *
842  * Returns: errno
843  */
844
845 static int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
846 {
847         struct gfs2_holder t_gh;
848         int error;
849
850         flush_workqueue(gfs2_delete_workqueue);
851         gfs2_quota_sync(sdp->sd_vfs, 0);
852         gfs2_statfs_sync(sdp->sd_vfs, 0);
853
854         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED, GL_NOCACHE,
855                                    &t_gh);
856         if (error && !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
857                 return error;
858
859         gfs2_meta_syncfs(sdp);
860         gfs2_log_shutdown(sdp);
861
862         clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
863
864         if (t_gh.gh_gl)
865                 gfs2_glock_dq_uninit(&t_gh);
866
867         gfs2_quota_cleanup(sdp);
868
869         return error;
870 }
871
872 static int gfs2_umount_recovery_wait(void *word)
873 {
874         schedule();
875         return 0;
876 }
877
878 /**
879  * gfs2_put_super - Unmount the filesystem
880  * @sb: The VFS superblock
881  *
882  */
883
884 static void gfs2_put_super(struct super_block *sb)
885 {
886         struct gfs2_sbd *sdp = sb->s_fs_info;
887         int error;
888         struct gfs2_jdesc *jd;
889
890         /*  Unfreeze the filesystem, if we need to  */
891
892         mutex_lock(&sdp->sd_freeze_lock);
893         if (sdp->sd_freeze_count)
894                 gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
895         mutex_unlock(&sdp->sd_freeze_lock);
896
897         /* No more recovery requests */
898         set_bit(SDF_NORECOVERY, &sdp->sd_flags);
899         smp_mb();
900
901         /* Wait on outstanding recovery */
902 restart:
903         spin_lock(&sdp->sd_jindex_spin);
904         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
905                 if (!test_bit(JDF_RECOVERY, &jd->jd_flags))
906                         continue;
907                 spin_unlock(&sdp->sd_jindex_spin);
908                 wait_on_bit(&jd->jd_flags, JDF_RECOVERY,
909                             gfs2_umount_recovery_wait, TASK_UNINTERRUPTIBLE);
910                 goto restart;
911         }
912         spin_unlock(&sdp->sd_jindex_spin);
913
914         kthread_stop(sdp->sd_quotad_process);
915         kthread_stop(sdp->sd_logd_process);
916
917         if (!(sb->s_flags & MS_RDONLY)) {
918                 error = gfs2_make_fs_ro(sdp);
919                 if (error)
920                         gfs2_io_error(sdp);
921         }
922         /*  At this point, we're through modifying the disk  */
923
924         /*  Release stuff  */
925
926         iput(sdp->sd_jindex);
927         iput(sdp->sd_statfs_inode);
928         iput(sdp->sd_rindex);
929         iput(sdp->sd_quota_inode);
930
931         gfs2_glock_put(sdp->sd_rename_gl);
932         gfs2_glock_put(sdp->sd_trans_gl);
933
934         if (!sdp->sd_args.ar_spectator) {
935                 gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
936                 gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
937                 gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
938                 gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
939                 iput(sdp->sd_sc_inode);
940                 iput(sdp->sd_qc_inode);
941         }
942
943         gfs2_glock_dq_uninit(&sdp->sd_live_gh);
944         gfs2_clear_rgrpd(sdp);
945         gfs2_jindex_free(sdp);
946         /*  Take apart glock structures and buffer lists  */
947         gfs2_gl_hash_clear(sdp);
948         /*  Unmount the locking protocol  */
949         gfs2_lm_unmount(sdp);
950
951         /*  At this point, we're through participating in the lockspace  */
952         gfs2_sys_fs_del(sdp);
953 }
954
955 /**
956  * gfs2_sync_fs - sync the filesystem
957  * @sb: the superblock
958  *
959  * Flushes the log to disk.
960  */
961
962 static int gfs2_sync_fs(struct super_block *sb, int wait)
963 {
964         struct gfs2_sbd *sdp = sb->s_fs_info;
965
966         gfs2_quota_sync(sb, -1);
967         if (wait && sdp)
968                 gfs2_log_flush(sdp, NULL);
969         return 0;
970 }
971
972 /**
973  * gfs2_freeze - prevent further writes to the filesystem
974  * @sb: the VFS structure for the filesystem
975  *
976  */
977
978 static int gfs2_freeze(struct super_block *sb)
979 {
980         struct gfs2_sbd *sdp = sb->s_fs_info;
981         int error;
982
983         if (test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
984                 return -EINVAL;
985
986         for (;;) {
987                 error = gfs2_freeze_fs(sdp);
988                 if (!error)
989                         break;
990
991                 switch (error) {
992                 case -EBUSY:
993                         fs_err(sdp, "waiting for recovery before freeze\n");
994                         break;
995
996                 default:
997                         fs_err(sdp, "error freezing FS: %d\n", error);
998                         break;
999                 }
1000
1001                 fs_err(sdp, "retrying...\n");
1002                 msleep(1000);
1003         }
1004         return 0;
1005 }
1006
1007 /**
1008  * gfs2_unfreeze - reallow writes to the filesystem
1009  * @sb: the VFS structure for the filesystem
1010  *
1011  */
1012
1013 static int gfs2_unfreeze(struct super_block *sb)
1014 {
1015         gfs2_unfreeze_fs(sb->s_fs_info);
1016         return 0;
1017 }
1018
1019 /**
1020  * statfs_fill - fill in the sg for a given RG
1021  * @rgd: the RG
1022  * @sc: the sc structure
1023  *
1024  * Returns: 0 on success, -ESTALE if the LVB is invalid
1025  */
1026
1027 static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
1028                             struct gfs2_statfs_change_host *sc)
1029 {
1030         gfs2_rgrp_verify(rgd);
1031         sc->sc_total += rgd->rd_data;
1032         sc->sc_free += rgd->rd_free;
1033         sc->sc_dinodes += rgd->rd_dinodes;
1034         return 0;
1035 }
1036
1037 /**
1038  * gfs2_statfs_slow - Stat a filesystem using asynchronous locking
1039  * @sdp: the filesystem
1040  * @sc: the sc info that will be returned
1041  *
1042  * Any error (other than a signal) will cause this routine to fall back
1043  * to the synchronous version.
1044  *
1045  * FIXME: This really shouldn't busy wait like this.
1046  *
1047  * Returns: errno
1048  */
1049
1050 static int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
1051 {
1052         struct gfs2_rgrpd *rgd_next;
1053         struct gfs2_holder *gha, *gh;
1054         unsigned int slots = 64;
1055         unsigned int x;
1056         int done;
1057         int error = 0, err;
1058
1059         memset(sc, 0, sizeof(struct gfs2_statfs_change_host));
1060         gha = kcalloc(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
1061         if (!gha)
1062                 return -ENOMEM;
1063
1064         rgd_next = gfs2_rgrpd_get_first(sdp);
1065
1066         for (;;) {
1067                 done = 1;
1068
1069                 for (x = 0; x < slots; x++) {
1070                         gh = gha + x;
1071
1072                         if (gh->gh_gl && gfs2_glock_poll(gh)) {
1073                                 err = gfs2_glock_wait(gh);
1074                                 if (err) {
1075                                         gfs2_holder_uninit(gh);
1076                                         error = err;
1077                                 } else {
1078                                         if (!error)
1079                                                 error = statfs_slow_fill(
1080                                                         gh->gh_gl->gl_object, sc);
1081                                         gfs2_glock_dq_uninit(gh);
1082                                 }
1083                         }
1084
1085                         if (gh->gh_gl)
1086                                 done = 0;
1087                         else if (rgd_next && !error) {
1088                                 error = gfs2_glock_nq_init(rgd_next->rd_gl,
1089                                                            LM_ST_SHARED,
1090                                                            GL_ASYNC,
1091                                                            gh);
1092                                 rgd_next = gfs2_rgrpd_get_next(rgd_next);
1093                                 done = 0;
1094                         }
1095
1096                         if (signal_pending(current))
1097                                 error = -ERESTARTSYS;
1098                 }
1099
1100                 if (done)
1101                         break;
1102
1103                 yield();
1104         }
1105
1106         kfree(gha);
1107         return error;
1108 }
1109
1110 /**
1111  * gfs2_statfs_i - Do a statfs
1112  * @sdp: the filesystem
1113  * @sg: the sg structure
1114  *
1115  * Returns: errno
1116  */
1117
1118 static int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
1119 {
1120         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
1121         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
1122
1123         spin_lock(&sdp->sd_statfs_spin);
1124
1125         *sc = *m_sc;
1126         sc->sc_total += l_sc->sc_total;
1127         sc->sc_free += l_sc->sc_free;
1128         sc->sc_dinodes += l_sc->sc_dinodes;
1129
1130         spin_unlock(&sdp->sd_statfs_spin);
1131
1132         if (sc->sc_free < 0)
1133                 sc->sc_free = 0;
1134         if (sc->sc_free > sc->sc_total)
1135                 sc->sc_free = sc->sc_total;
1136         if (sc->sc_dinodes < 0)
1137                 sc->sc_dinodes = 0;
1138
1139         return 0;
1140 }
1141
1142 /**
1143  * gfs2_statfs - Gather and return stats about the filesystem
1144  * @sb: The superblock
1145  * @statfsbuf: The buffer
1146  *
1147  * Returns: 0 on success or error code
1148  */
1149
1150 static int gfs2_statfs(struct dentry *dentry, struct kstatfs *buf)
1151 {
1152         struct super_block *sb = dentry->d_inode->i_sb;
1153         struct gfs2_sbd *sdp = sb->s_fs_info;
1154         struct gfs2_statfs_change_host sc;
1155         int error;
1156
1157         error = gfs2_rindex_update(sdp);
1158         if (error)
1159                 return error;
1160
1161         if (gfs2_tune_get(sdp, gt_statfs_slow))
1162                 error = gfs2_statfs_slow(sdp, &sc);
1163         else
1164                 error = gfs2_statfs_i(sdp, &sc);
1165
1166         if (error)
1167                 return error;
1168
1169         buf->f_type = GFS2_MAGIC;
1170         buf->f_bsize = sdp->sd_sb.sb_bsize;
1171         buf->f_blocks = sc.sc_total;
1172         buf->f_bfree = sc.sc_free;
1173         buf->f_bavail = sc.sc_free;
1174         buf->f_files = sc.sc_dinodes + sc.sc_free;
1175         buf->f_ffree = sc.sc_free;
1176         buf->f_namelen = GFS2_FNAMESIZE;
1177
1178         return 0;
1179 }
1180
1181 /**
1182  * gfs2_remount_fs - called when the FS is remounted
1183  * @sb:  the filesystem
1184  * @flags:  the remount flags
1185  * @data:  extra data passed in (not used right now)
1186  *
1187  * Returns: errno
1188  */
1189
1190 static int gfs2_remount_fs(struct super_block *sb, int *flags, char *data)
1191 {
1192         struct gfs2_sbd *sdp = sb->s_fs_info;
1193         struct gfs2_args args = sdp->sd_args; /* Default to current settings */
1194         struct gfs2_tune *gt = &sdp->sd_tune;
1195         int error;
1196
1197         spin_lock(&gt->gt_spin);
1198         args.ar_commit = gt->gt_logd_secs;
1199         args.ar_quota_quantum = gt->gt_quota_quantum;
1200         if (gt->gt_statfs_slow)
1201                 args.ar_statfs_quantum = 0;
1202         else
1203                 args.ar_statfs_quantum = gt->gt_statfs_quantum;
1204         spin_unlock(&gt->gt_spin);
1205         error = gfs2_mount_args(&args, data);
1206         if (error)
1207                 return error;
1208
1209         /* Not allowed to change locking details */
1210         if (strcmp(args.ar_lockproto, sdp->sd_args.ar_lockproto) ||
1211             strcmp(args.ar_locktable, sdp->sd_args.ar_locktable) ||
1212             strcmp(args.ar_hostdata, sdp->sd_args.ar_hostdata))
1213                 return -EINVAL;
1214
1215         /* Some flags must not be changed */
1216         if (args_neq(&args, &sdp->sd_args, spectator) ||
1217             args_neq(&args, &sdp->sd_args, localflocks) ||
1218             args_neq(&args, &sdp->sd_args, meta))
1219                 return -EINVAL;
1220
1221         if (sdp->sd_args.ar_spectator)
1222                 *flags |= MS_RDONLY;
1223
1224         if ((sb->s_flags ^ *flags) & MS_RDONLY) {
1225                 if (*flags & MS_RDONLY)
1226                         error = gfs2_make_fs_ro(sdp);
1227                 else
1228                         error = gfs2_make_fs_rw(sdp);
1229                 if (error)
1230                         return error;
1231         }
1232
1233         sdp->sd_args = args;
1234         if (sdp->sd_args.ar_posix_acl)
1235                 sb->s_flags |= MS_POSIXACL;
1236         else
1237                 sb->s_flags &= ~MS_POSIXACL;
1238         if (sdp->sd_args.ar_nobarrier)
1239                 set_bit(SDF_NOBARRIERS, &sdp->sd_flags);
1240         else
1241                 clear_bit(SDF_NOBARRIERS, &sdp->sd_flags);
1242         spin_lock(&gt->gt_spin);
1243         gt->gt_logd_secs = args.ar_commit;
1244         gt->gt_quota_quantum = args.ar_quota_quantum;
1245         if (args.ar_statfs_quantum) {
1246                 gt->gt_statfs_slow = 0;
1247                 gt->gt_statfs_quantum = args.ar_statfs_quantum;
1248         }
1249         else {
1250                 gt->gt_statfs_slow = 1;
1251                 gt->gt_statfs_quantum = 30;
1252         }
1253         spin_unlock(&gt->gt_spin);
1254
1255         gfs2_online_uevent(sdp);
1256         return 0;
1257 }
1258
1259 /**
1260  * gfs2_drop_inode - Drop an inode (test for remote unlink)
1261  * @inode: The inode to drop
1262  *
1263  * If we've received a callback on an iopen lock then its because a
1264  * remote node tried to deallocate the inode but failed due to this node
1265  * still having the inode open. Here we mark the link count zero
1266  * since we know that it must have reached zero if the GLF_DEMOTE flag
1267  * is set on the iopen glock. If we didn't do a disk read since the
1268  * remote node removed the final link then we might otherwise miss
1269  * this event. This check ensures that this node will deallocate the
1270  * inode's blocks, or alternatively pass the baton on to another
1271  * node for later deallocation.
1272  */
1273
1274 static int gfs2_drop_inode(struct inode *inode)
1275 {
1276         struct gfs2_inode *ip = GFS2_I(inode);
1277
1278         if (inode->i_nlink) {
1279                 struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
1280                 if (gl && test_bit(GLF_DEMOTE, &gl->gl_flags))
1281                         clear_nlink(inode);
1282         }
1283         return generic_drop_inode(inode);
1284 }
1285
1286 static int is_ancestor(const struct dentry *d1, const struct dentry *d2)
1287 {
1288         do {
1289                 if (d1 == d2)
1290                         return 1;
1291                 d1 = d1->d_parent;
1292         } while (!IS_ROOT(d1));
1293         return 0;
1294 }
1295
1296 /**
1297  * gfs2_show_options - Show mount options for /proc/mounts
1298  * @s: seq_file structure
1299  * @root: root of this (sub)tree
1300  *
1301  * Returns: 0 on success or error code
1302  */
1303
1304 static int gfs2_show_options(struct seq_file *s, struct dentry *root)
1305 {
1306         struct gfs2_sbd *sdp = root->d_sb->s_fs_info;
1307         struct gfs2_args *args = &sdp->sd_args;
1308         int val;
1309
1310         if (is_ancestor(root, sdp->sd_master_dir))
1311                 seq_printf(s, ",meta");
1312         if (args->ar_lockproto[0])
1313                 seq_printf(s, ",lockproto=%s", args->ar_lockproto);
1314         if (args->ar_locktable[0])
1315                 seq_printf(s, ",locktable=%s", args->ar_locktable);
1316         if (args->ar_hostdata[0])
1317                 seq_printf(s, ",hostdata=%s", args->ar_hostdata);
1318         if (args->ar_spectator)
1319                 seq_printf(s, ",spectator");
1320         if (args->ar_localflocks)
1321                 seq_printf(s, ",localflocks");
1322         if (args->ar_debug)
1323                 seq_printf(s, ",debug");
1324         if (args->ar_posix_acl)
1325                 seq_printf(s, ",acl");
1326         if (args->ar_quota != GFS2_QUOTA_DEFAULT) {
1327                 char *state;
1328                 switch (args->ar_quota) {
1329                 case GFS2_QUOTA_OFF:
1330                         state = "off";
1331                         break;
1332                 case GFS2_QUOTA_ACCOUNT:
1333                         state = "account";
1334                         break;
1335                 case GFS2_QUOTA_ON:
1336                         state = "on";
1337                         break;
1338                 default:
1339                         state = "unknown";
1340                         break;
1341                 }
1342                 seq_printf(s, ",quota=%s", state);
1343         }
1344         if (args->ar_suiddir)
1345                 seq_printf(s, ",suiddir");
1346         if (args->ar_data != GFS2_DATA_DEFAULT) {
1347                 char *state;
1348                 switch (args->ar_data) {
1349                 case GFS2_DATA_WRITEBACK:
1350                         state = "writeback";
1351                         break;
1352                 case GFS2_DATA_ORDERED:
1353                         state = "ordered";
1354                         break;
1355                 default:
1356                         state = "unknown";
1357                         break;
1358                 }
1359                 seq_printf(s, ",data=%s", state);
1360         }
1361         if (args->ar_discard)
1362                 seq_printf(s, ",discard");
1363         val = sdp->sd_tune.gt_logd_secs;
1364         if (val != 30)
1365                 seq_printf(s, ",commit=%d", val);
1366         val = sdp->sd_tune.gt_statfs_quantum;
1367         if (val != 30)
1368                 seq_printf(s, ",statfs_quantum=%d", val);
1369         else if (sdp->sd_tune.gt_statfs_slow)
1370                 seq_puts(s, ",statfs_quantum=0");
1371         val = sdp->sd_tune.gt_quota_quantum;
1372         if (val != 60)
1373                 seq_printf(s, ",quota_quantum=%d", val);
1374         if (args->ar_statfs_percent)
1375                 seq_printf(s, ",statfs_percent=%d", args->ar_statfs_percent);
1376         if (args->ar_errors != GFS2_ERRORS_DEFAULT) {
1377                 const char *state;
1378
1379                 switch (args->ar_errors) {
1380                 case GFS2_ERRORS_WITHDRAW:
1381                         state = "withdraw";
1382                         break;
1383                 case GFS2_ERRORS_PANIC:
1384                         state = "panic";
1385                         break;
1386                 default:
1387                         state = "unknown";
1388                         break;
1389                 }
1390                 seq_printf(s, ",errors=%s", state);
1391         }
1392         if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags))
1393                 seq_printf(s, ",nobarrier");
1394         if (test_bit(SDF_DEMOTE, &sdp->sd_flags))
1395                 seq_printf(s, ",demote_interface_used");
1396         if (args->ar_rgrplvb)
1397                 seq_printf(s, ",rgrplvb");
1398         return 0;
1399 }
1400
1401 static void gfs2_final_release_pages(struct gfs2_inode *ip)
1402 {
1403         struct inode *inode = &ip->i_inode;
1404         struct gfs2_glock *gl = ip->i_gl;
1405
1406         truncate_inode_pages(gfs2_glock2aspace(ip->i_gl), 0);
1407         truncate_inode_pages(&inode->i_data, 0);
1408
1409         if (atomic_read(&gl->gl_revokes) == 0) {
1410                 clear_bit(GLF_LFLUSH, &gl->gl_flags);
1411                 clear_bit(GLF_DIRTY, &gl->gl_flags);
1412         }
1413 }
1414
1415 static int gfs2_dinode_dealloc(struct gfs2_inode *ip)
1416 {
1417         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1418         struct gfs2_rgrpd *rgd;
1419         struct gfs2_holder gh;
1420         int error;
1421
1422         if (gfs2_get_inode_blocks(&ip->i_inode) != 1) {
1423                 gfs2_consist_inode(ip);
1424                 return -EIO;
1425         }
1426
1427         error = gfs2_rindex_update(sdp);
1428         if (error)
1429                 return error;
1430
1431         error = gfs2_quota_hold(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
1432         if (error)
1433                 return error;
1434
1435         rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr, 1);
1436         if (!rgd) {
1437                 gfs2_consist_inode(ip);
1438                 error = -EIO;
1439                 goto out_qs;
1440         }
1441
1442         error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, &gh);
1443         if (error)
1444                 goto out_qs;
1445
1446         error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_STATFS + RES_QUOTA,
1447                                  sdp->sd_jdesc->jd_blocks);
1448         if (error)
1449                 goto out_rg_gunlock;
1450
1451         gfs2_free_di(rgd, ip);
1452
1453         gfs2_final_release_pages(ip);
1454
1455         gfs2_trans_end(sdp);
1456
1457 out_rg_gunlock:
1458         gfs2_glock_dq_uninit(&gh);
1459 out_qs:
1460         gfs2_quota_unhold(ip);
1461         return error;
1462 }
1463
1464 /**
1465  * gfs2_evict_inode - Remove an inode from cache
1466  * @inode: The inode to evict
1467  *
1468  * There are three cases to consider:
1469  * 1. i_nlink == 0, we are final opener (and must deallocate)
1470  * 2. i_nlink == 0, we are not the final opener (and cannot deallocate)
1471  * 3. i_nlink > 0
1472  *
1473  * If the fs is read only, then we have to treat all cases as per #3
1474  * since we are unable to do any deallocation. The inode will be
1475  * deallocated by the next read/write node to attempt an allocation
1476  * in the same resource group
1477  *
1478  * We have to (at the moment) hold the inodes main lock to cover
1479  * the gap between unlocking the shared lock on the iopen lock and
1480  * taking the exclusive lock. I'd rather do a shared -> exclusive
1481  * conversion on the iopen lock, but we can change that later. This
1482  * is safe, just less efficient.
1483  */
1484
1485 static void gfs2_evict_inode(struct inode *inode)
1486 {
1487         struct super_block *sb = inode->i_sb;
1488         struct gfs2_sbd *sdp = sb->s_fs_info;
1489         struct gfs2_inode *ip = GFS2_I(inode);
1490         struct gfs2_holder gh;
1491         int error;
1492
1493         if (inode->i_nlink || (sb->s_flags & MS_RDONLY))
1494                 goto out;
1495
1496         /* Must not read inode block until block type has been verified */
1497         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, &gh);
1498         if (unlikely(error)) {
1499                 gfs2_glock_dq_uninit(&ip->i_iopen_gh);
1500                 goto out;
1501         }
1502
1503         if (!test_bit(GIF_ALLOC_FAILED, &ip->i_flags)) {
1504                 error = gfs2_check_blk_type(sdp, ip->i_no_addr, GFS2_BLKST_UNLINKED);
1505                 if (error)
1506                         goto out_truncate;
1507         }
1508
1509         if (test_bit(GIF_INVALID, &ip->i_flags)) {
1510                 error = gfs2_inode_refresh(ip);
1511                 if (error)
1512                         goto out_truncate;
1513         }
1514
1515         ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1516         gfs2_glock_dq_wait(&ip->i_iopen_gh);
1517         gfs2_holder_reinit(LM_ST_EXCLUSIVE, LM_FLAG_TRY_1CB | GL_NOCACHE, &ip->i_iopen_gh);
1518         error = gfs2_glock_nq(&ip->i_iopen_gh);
1519         if (error)
1520                 goto out_truncate;
1521
1522         /* Case 1 starts here */
1523
1524         if (S_ISDIR(inode->i_mode) &&
1525             (ip->i_diskflags & GFS2_DIF_EXHASH)) {
1526                 error = gfs2_dir_exhash_dealloc(ip);
1527                 if (error)
1528                         goto out_unlock;
1529         }
1530
1531         if (ip->i_eattr) {
1532                 error = gfs2_ea_dealloc(ip);
1533                 if (error)
1534                         goto out_unlock;
1535         }
1536
1537         if (!gfs2_is_stuffed(ip)) {
1538                 error = gfs2_file_dealloc(ip);
1539                 if (error)
1540                         goto out_unlock;
1541         }
1542
1543         error = gfs2_dinode_dealloc(ip);
1544         goto out_unlock;
1545
1546 out_truncate:
1547         gfs2_log_flush(sdp, ip->i_gl);
1548         if (test_bit(GLF_DIRTY, &ip->i_gl->gl_flags)) {
1549                 struct address_space *metamapping = gfs2_glock2aspace(ip->i_gl);
1550                 filemap_fdatawrite(metamapping);
1551                 filemap_fdatawait(metamapping);
1552         }
1553         write_inode_now(inode, 1);
1554         gfs2_ail_flush(ip->i_gl, 0);
1555
1556         /* Case 2 starts here */
1557         error = gfs2_trans_begin(sdp, 0, sdp->sd_jdesc->jd_blocks);
1558         if (error)
1559                 goto out_unlock;
1560         /* Needs to be done before glock release & also in a transaction */
1561         truncate_inode_pages(&inode->i_data, 0);
1562         gfs2_trans_end(sdp);
1563
1564 out_unlock:
1565         /* Error path for case 1 */
1566         if (gfs2_rs_active(ip->i_res))
1567                 gfs2_rs_deltree(ip, ip->i_res);
1568
1569         if (test_bit(HIF_HOLDER, &ip->i_iopen_gh.gh_iflags))
1570                 gfs2_glock_dq(&ip->i_iopen_gh);
1571         gfs2_holder_uninit(&ip->i_iopen_gh);
1572         gfs2_glock_dq_uninit(&gh);
1573         if (error && error != GLR_TRYFAILED && error != -EROFS)
1574                 fs_warn(sdp, "gfs2_evict_inode: %d\n", error);
1575 out:
1576         /* Case 3 starts here */
1577         truncate_inode_pages(&inode->i_data, 0);
1578         gfs2_rs_delete(ip);
1579         clear_inode(inode);
1580         gfs2_dir_hash_inval(ip);
1581         ip->i_gl->gl_object = NULL;
1582         flush_delayed_work(&ip->i_gl->gl_work);
1583         gfs2_glock_add_to_lru(ip->i_gl);
1584         gfs2_glock_put(ip->i_gl);
1585         ip->i_gl = NULL;
1586         if (ip->i_iopen_gh.gh_gl) {
1587                 ip->i_iopen_gh.gh_gl->gl_object = NULL;
1588                 gfs2_glock_dq_uninit(&ip->i_iopen_gh);
1589         }
1590 }
1591
1592 static struct inode *gfs2_alloc_inode(struct super_block *sb)
1593 {
1594         struct gfs2_inode *ip;
1595
1596         ip = kmem_cache_alloc(gfs2_inode_cachep, GFP_KERNEL);
1597         if (ip) {
1598                 ip->i_flags = 0;
1599                 ip->i_gl = NULL;
1600                 ip->i_rgd = NULL;
1601                 ip->i_res = NULL;
1602         }
1603         return &ip->i_inode;
1604 }
1605
1606 static void gfs2_i_callback(struct rcu_head *head)
1607 {
1608         struct inode *inode = container_of(head, struct inode, i_rcu);
1609         kmem_cache_free(gfs2_inode_cachep, inode);
1610 }
1611
1612 static void gfs2_destroy_inode(struct inode *inode)
1613 {
1614         call_rcu(&inode->i_rcu, gfs2_i_callback);
1615 }
1616
1617 const struct super_operations gfs2_super_ops = {
1618         .alloc_inode            = gfs2_alloc_inode,
1619         .destroy_inode          = gfs2_destroy_inode,
1620         .write_inode            = gfs2_write_inode,
1621         .dirty_inode            = gfs2_dirty_inode,
1622         .evict_inode            = gfs2_evict_inode,
1623         .put_super              = gfs2_put_super,
1624         .sync_fs                = gfs2_sync_fs,
1625         .freeze_fs              = gfs2_freeze,
1626         .unfreeze_fs            = gfs2_unfreeze,
1627         .statfs                 = gfs2_statfs,
1628         .remount_fs             = gfs2_remount_fs,
1629         .drop_inode             = gfs2_drop_inode,
1630         .show_options           = gfs2_show_options,
1631 };
1632