These changes are a raw update to a vanilla kernel 4.1.10, with the
[kvmfornfv.git] / kernel / 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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11
12 #include <linux/bio.h>
13 #include <linux/sched.h>
14 #include <linux/slab.h>
15 #include <linux/spinlock.h>
16 #include <linux/completion.h>
17 #include <linux/buffer_head.h>
18 #include <linux/statfs.h>
19 #include <linux/seq_file.h>
20 #include <linux/mount.h>
21 #include <linux/kthread.h>
22 #include <linux/delay.h>
23 #include <linux/gfs2_ondisk.h>
24 #include <linux/crc32.h>
25 #include <linux/time.h>
26 #include <linux/wait.h>
27 #include <linux/writeback.h>
28 #include <linux/backing-dev.h>
29 #include <linux/kernel.h>
30
31 #include "gfs2.h"
32 #include "incore.h"
33 #include "bmap.h"
34 #include "dir.h"
35 #include "glock.h"
36 #include "glops.h"
37 #include "inode.h"
38 #include "log.h"
39 #include "meta_io.h"
40 #include "quota.h"
41 #include "recovery.h"
42 #include "rgrp.h"
43 #include "super.h"
44 #include "trans.h"
45 #include "util.h"
46 #include "sys.h"
47 #include "xattr.h"
48
49 #define args_neq(a1, a2, x) ((a1)->ar_##x != (a2)->ar_##x)
50
51 enum {
52         Opt_lockproto,
53         Opt_locktable,
54         Opt_hostdata,
55         Opt_spectator,
56         Opt_ignore_local_fs,
57         Opt_localflocks,
58         Opt_localcaching,
59         Opt_debug,
60         Opt_nodebug,
61         Opt_upgrade,
62         Opt_acl,
63         Opt_noacl,
64         Opt_quota_off,
65         Opt_quota_account,
66         Opt_quota_on,
67         Opt_quota,
68         Opt_noquota,
69         Opt_suiddir,
70         Opt_nosuiddir,
71         Opt_data_writeback,
72         Opt_data_ordered,
73         Opt_meta,
74         Opt_discard,
75         Opt_nodiscard,
76         Opt_commit,
77         Opt_err_withdraw,
78         Opt_err_panic,
79         Opt_statfs_quantum,
80         Opt_statfs_percent,
81         Opt_quota_quantum,
82         Opt_barrier,
83         Opt_nobarrier,
84         Opt_rgrplvb,
85         Opt_norgrplvb,
86         Opt_error,
87 };
88
89 static const match_table_t tokens = {
90         {Opt_lockproto, "lockproto=%s"},
91         {Opt_locktable, "locktable=%s"},
92         {Opt_hostdata, "hostdata=%s"},
93         {Opt_spectator, "spectator"},
94         {Opt_spectator, "norecovery"},
95         {Opt_ignore_local_fs, "ignore_local_fs"},
96         {Opt_localflocks, "localflocks"},
97         {Opt_localcaching, "localcaching"},
98         {Opt_debug, "debug"},
99         {Opt_nodebug, "nodebug"},
100         {Opt_upgrade, "upgrade"},
101         {Opt_acl, "acl"},
102         {Opt_noacl, "noacl"},
103         {Opt_quota_off, "quota=off"},
104         {Opt_quota_account, "quota=account"},
105         {Opt_quota_on, "quota=on"},
106         {Opt_quota, "quota"},
107         {Opt_noquota, "noquota"},
108         {Opt_suiddir, "suiddir"},
109         {Opt_nosuiddir, "nosuiddir"},
110         {Opt_data_writeback, "data=writeback"},
111         {Opt_data_ordered, "data=ordered"},
112         {Opt_meta, "meta"},
113         {Opt_discard, "discard"},
114         {Opt_nodiscard, "nodiscard"},
115         {Opt_commit, "commit=%d"},
116         {Opt_err_withdraw, "errors=withdraw"},
117         {Opt_err_panic, "errors=panic"},
118         {Opt_statfs_quantum, "statfs_quantum=%d"},
119         {Opt_statfs_percent, "statfs_percent=%d"},
120         {Opt_quota_quantum, "quota_quantum=%d"},
121         {Opt_barrier, "barrier"},
122         {Opt_nobarrier, "nobarrier"},
123         {Opt_rgrplvb, "rgrplvb"},
124         {Opt_norgrplvb, "norgrplvb"},
125         {Opt_error, NULL}
126 };
127
128 /**
129  * gfs2_mount_args - Parse mount options
130  * @args: The structure into which the parsed options will be written
131  * @options: The options to parse
132  *
133  * Return: errno
134  */
135
136 int gfs2_mount_args(struct gfs2_args *args, char *options)
137 {
138         char *o;
139         int token;
140         substring_t tmp[MAX_OPT_ARGS];
141         int rv;
142
143         /* Split the options into tokens with the "," character and
144            process them */
145
146         while (1) {
147                 o = strsep(&options, ",");
148                 if (o == NULL)
149                         break;
150                 if (*o == '\0')
151                         continue;
152
153                 token = match_token(o, tokens, tmp);
154                 switch (token) {
155                 case Opt_lockproto:
156                         match_strlcpy(args->ar_lockproto, &tmp[0],
157                                       GFS2_LOCKNAME_LEN);
158                         break;
159                 case Opt_locktable:
160                         match_strlcpy(args->ar_locktable, &tmp[0],
161                                       GFS2_LOCKNAME_LEN);
162                         break;
163                 case Opt_hostdata:
164                         match_strlcpy(args->ar_hostdata, &tmp[0],
165                                       GFS2_LOCKNAME_LEN);
166                         break;
167                 case Opt_spectator:
168                         args->ar_spectator = 1;
169                         break;
170                 case Opt_ignore_local_fs:
171                         /* Retained for backwards compat only */
172                         break;
173                 case Opt_localflocks:
174                         args->ar_localflocks = 1;
175                         break;
176                 case Opt_localcaching:
177                         /* Retained for backwards compat only */
178                         break;
179                 case Opt_debug:
180                         if (args->ar_errors == GFS2_ERRORS_PANIC) {
181                                 pr_warn("-o debug and -o errors=panic are mutually exclusive\n");
182                                 return -EINVAL;
183                         }
184                         args->ar_debug = 1;
185                         break;
186                 case Opt_nodebug:
187                         args->ar_debug = 0;
188                         break;
189                 case Opt_upgrade:
190                         /* Retained for backwards compat only */
191                         break;
192                 case Opt_acl:
193                         args->ar_posix_acl = 1;
194                         break;
195                 case Opt_noacl:
196                         args->ar_posix_acl = 0;
197                         break;
198                 case Opt_quota_off:
199                 case Opt_noquota:
200                         args->ar_quota = GFS2_QUOTA_OFF;
201                         break;
202                 case Opt_quota_account:
203                         args->ar_quota = GFS2_QUOTA_ACCOUNT;
204                         break;
205                 case Opt_quota_on:
206                 case Opt_quota:
207                         args->ar_quota = GFS2_QUOTA_ON;
208                         break;
209                 case Opt_suiddir:
210                         args->ar_suiddir = 1;
211                         break;
212                 case Opt_nosuiddir:
213                         args->ar_suiddir = 0;
214                         break;
215                 case Opt_data_writeback:
216                         args->ar_data = GFS2_DATA_WRITEBACK;
217                         break;
218                 case Opt_data_ordered:
219                         args->ar_data = GFS2_DATA_ORDERED;
220                         break;
221                 case Opt_meta:
222                         args->ar_meta = 1;
223                         break;
224                 case Opt_discard:
225                         args->ar_discard = 1;
226                         break;
227                 case Opt_nodiscard:
228                         args->ar_discard = 0;
229                         break;
230                 case Opt_commit:
231                         rv = match_int(&tmp[0], &args->ar_commit);
232                         if (rv || args->ar_commit <= 0) {
233                                 pr_warn("commit mount option requires a positive numeric argument\n");
234                                 return rv ? rv : -EINVAL;
235                         }
236                         break;
237                 case Opt_statfs_quantum:
238                         rv = match_int(&tmp[0], &args->ar_statfs_quantum);
239                         if (rv || args->ar_statfs_quantum < 0) {
240                                 pr_warn("statfs_quantum mount option requires a non-negative numeric argument\n");
241                                 return rv ? rv : -EINVAL;
242                         }
243                         break;
244                 case Opt_quota_quantum:
245                         rv = match_int(&tmp[0], &args->ar_quota_quantum);
246                         if (rv || args->ar_quota_quantum <= 0) {
247                                 pr_warn("quota_quantum mount option requires a positive numeric argument\n");
248                                 return rv ? rv : -EINVAL;
249                         }
250                         break;
251                 case Opt_statfs_percent:
252                         rv = match_int(&tmp[0], &args->ar_statfs_percent);
253                         if (rv || args->ar_statfs_percent < 0 ||
254                             args->ar_statfs_percent > 100) {
255                                 pr_warn("statfs_percent mount option requires a numeric argument between 0 and 100\n");
256                                 return rv ? rv : -EINVAL;
257                         }
258                         break;
259                 case Opt_err_withdraw:
260                         args->ar_errors = GFS2_ERRORS_WITHDRAW;
261                         break;
262                 case Opt_err_panic:
263                         if (args->ar_debug) {
264                                 pr_warn("-o debug and -o errors=panic are mutually exclusive\n");
265                                 return -EINVAL;
266                         }
267                         args->ar_errors = GFS2_ERRORS_PANIC;
268                         break;
269                 case Opt_barrier:
270                         args->ar_nobarrier = 0;
271                         break;
272                 case Opt_nobarrier:
273                         args->ar_nobarrier = 1;
274                         break;
275                 case Opt_rgrplvb:
276                         args->ar_rgrplvb = 1;
277                         break;
278                 case Opt_norgrplvb:
279                         args->ar_rgrplvb = 0;
280                         break;
281                 case Opt_error:
282                 default:
283                         pr_warn("invalid mount option: %s\n", o);
284                         return -EINVAL;
285                 }
286         }
287
288         return 0;
289 }
290
291 /**
292  * gfs2_jindex_free - Clear all the journal index information
293  * @sdp: The GFS2 superblock
294  *
295  */
296
297 void gfs2_jindex_free(struct gfs2_sbd *sdp)
298 {
299         struct list_head list;
300         struct gfs2_jdesc *jd;
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                 gfs2_free_journal_extents(jd);
311                 list_del(&jd->jd_list);
312                 iput(jd->jd_inode);
313                 kfree(jd);
314         }
315 }
316
317 static struct gfs2_jdesc *jdesc_find_i(struct list_head *head, unsigned int jid)
318 {
319         struct gfs2_jdesc *jd;
320         int found = 0;
321
322         list_for_each_entry(jd, head, jd_list) {
323                 if (jd->jd_jid == jid) {
324                         found = 1;
325                         break;
326                 }
327         }
328
329         if (!found)
330                 jd = NULL;
331
332         return jd;
333 }
334
335 struct gfs2_jdesc *gfs2_jdesc_find(struct gfs2_sbd *sdp, unsigned int jid)
336 {
337         struct gfs2_jdesc *jd;
338
339         spin_lock(&sdp->sd_jindex_spin);
340         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
341         spin_unlock(&sdp->sd_jindex_spin);
342
343         return jd;
344 }
345
346 int gfs2_jdesc_check(struct gfs2_jdesc *jd)
347 {
348         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
349         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
350         u64 size = i_size_read(jd->jd_inode);
351
352         if (gfs2_check_internal_file_size(jd->jd_inode, 8 << 20, 1 << 30))
353                 return -EIO;
354
355         jd->jd_blocks = size >> sdp->sd_sb.sb_bsize_shift;
356
357         if (gfs2_write_alloc_required(ip, 0, size)) {
358                 gfs2_consist_inode(ip);
359                 return -EIO;
360         }
361
362         return 0;
363 }
364
365 static int init_threads(struct gfs2_sbd *sdp)
366 {
367         struct task_struct *p;
368         int error = 0;
369
370         p = kthread_run(gfs2_logd, sdp, "gfs2_logd");
371         if (IS_ERR(p)) {
372                 error = PTR_ERR(p);
373                 fs_err(sdp, "can't start logd thread: %d\n", error);
374                 return error;
375         }
376         sdp->sd_logd_process = p;
377
378         p = kthread_run(gfs2_quotad, sdp, "gfs2_quotad");
379         if (IS_ERR(p)) {
380                 error = PTR_ERR(p);
381                 fs_err(sdp, "can't start quotad thread: %d\n", error);
382                 goto fail;
383         }
384         sdp->sd_quotad_process = p;
385         return 0;
386
387 fail:
388         kthread_stop(sdp->sd_logd_process);
389         return error;
390 }
391
392 /**
393  * gfs2_make_fs_rw - Turn a Read-Only FS into a Read-Write one
394  * @sdp: the filesystem
395  *
396  * Returns: errno
397  */
398
399 int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
400 {
401         struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
402         struct gfs2_glock *j_gl = ip->i_gl;
403         struct gfs2_holder freeze_gh;
404         struct gfs2_log_header_host head;
405         int error;
406
407         error = init_threads(sdp);
408         if (error)
409                 return error;
410
411         error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED, 0,
412                                    &freeze_gh);
413         if (error)
414                 goto fail_threads;
415
416         j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
417
418         error = gfs2_find_jhead(sdp->sd_jdesc, &head);
419         if (error)
420                 goto fail;
421
422         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
423                 gfs2_consist(sdp);
424                 error = -EIO;
425                 goto fail;
426         }
427
428         /*  Initialize some head of the log stuff  */
429         sdp->sd_log_sequence = head.lh_sequence + 1;
430         gfs2_log_pointers_init(sdp, head.lh_blkno);
431
432         error = gfs2_quota_init(sdp);
433         if (error)
434                 goto fail;
435
436         set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
437
438         gfs2_glock_dq_uninit(&freeze_gh);
439
440         return 0;
441
442 fail:
443         freeze_gh.gh_flags |= GL_NOCACHE;
444         gfs2_glock_dq_uninit(&freeze_gh);
445 fail_threads:
446         kthread_stop(sdp->sd_quotad_process);
447         kthread_stop(sdp->sd_logd_process);
448         return error;
449 }
450
451 void gfs2_statfs_change_in(struct gfs2_statfs_change_host *sc, const void *buf)
452 {
453         const struct gfs2_statfs_change *str = buf;
454
455         sc->sc_total = be64_to_cpu(str->sc_total);
456         sc->sc_free = be64_to_cpu(str->sc_free);
457         sc->sc_dinodes = be64_to_cpu(str->sc_dinodes);
458 }
459
460 static void gfs2_statfs_change_out(const struct gfs2_statfs_change_host *sc, void *buf)
461 {
462         struct gfs2_statfs_change *str = buf;
463
464         str->sc_total = cpu_to_be64(sc->sc_total);
465         str->sc_free = cpu_to_be64(sc->sc_free);
466         str->sc_dinodes = cpu_to_be64(sc->sc_dinodes);
467 }
468
469 int gfs2_statfs_init(struct gfs2_sbd *sdp)
470 {
471         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
472         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
473         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
474         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
475         struct buffer_head *m_bh, *l_bh;
476         struct gfs2_holder gh;
477         int error;
478
479         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
480                                    &gh);
481         if (error)
482                 return error;
483
484         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
485         if (error)
486                 goto out;
487
488         if (sdp->sd_args.ar_spectator) {
489                 spin_lock(&sdp->sd_statfs_spin);
490                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
491                                       sizeof(struct gfs2_dinode));
492                 spin_unlock(&sdp->sd_statfs_spin);
493         } else {
494                 error = gfs2_meta_inode_buffer(l_ip, &l_bh);
495                 if (error)
496                         goto out_m_bh;
497
498                 spin_lock(&sdp->sd_statfs_spin);
499                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
500                                       sizeof(struct gfs2_dinode));
501                 gfs2_statfs_change_in(l_sc, l_bh->b_data +
502                                       sizeof(struct gfs2_dinode));
503                 spin_unlock(&sdp->sd_statfs_spin);
504
505                 brelse(l_bh);
506         }
507
508 out_m_bh:
509         brelse(m_bh);
510 out:
511         gfs2_glock_dq_uninit(&gh);
512         return 0;
513 }
514
515 void gfs2_statfs_change(struct gfs2_sbd *sdp, s64 total, s64 free,
516                         s64 dinodes)
517 {
518         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
519         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
520         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
521         struct buffer_head *l_bh;
522         s64 x, y;
523         int need_sync = 0;
524         int error;
525
526         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
527         if (error)
528                 return;
529
530         gfs2_trans_add_meta(l_ip->i_gl, l_bh);
531
532         spin_lock(&sdp->sd_statfs_spin);
533         l_sc->sc_total += total;
534         l_sc->sc_free += free;
535         l_sc->sc_dinodes += dinodes;
536         gfs2_statfs_change_out(l_sc, l_bh->b_data + sizeof(struct gfs2_dinode));
537         if (sdp->sd_args.ar_statfs_percent) {
538                 x = 100 * l_sc->sc_free;
539                 y = m_sc->sc_free * sdp->sd_args.ar_statfs_percent;
540                 if (x >= y || x <= -y)
541                         need_sync = 1;
542         }
543         spin_unlock(&sdp->sd_statfs_spin);
544
545         brelse(l_bh);
546         if (need_sync)
547                 gfs2_wake_up_statfs(sdp);
548 }
549
550 void update_statfs(struct gfs2_sbd *sdp, struct buffer_head *m_bh,
551                    struct buffer_head *l_bh)
552 {
553         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
554         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
555         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
556         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
557
558         gfs2_trans_add_meta(l_ip->i_gl, l_bh);
559
560         spin_lock(&sdp->sd_statfs_spin);
561         m_sc->sc_total += l_sc->sc_total;
562         m_sc->sc_free += l_sc->sc_free;
563         m_sc->sc_dinodes += l_sc->sc_dinodes;
564         memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
565         memset(l_bh->b_data + sizeof(struct gfs2_dinode),
566                0, sizeof(struct gfs2_statfs_change));
567         spin_unlock(&sdp->sd_statfs_spin);
568
569         gfs2_trans_add_meta(m_ip->i_gl, m_bh);
570         gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
571 }
572
573 int gfs2_statfs_sync(struct super_block *sb, int type)
574 {
575         struct gfs2_sbd *sdp = sb->s_fs_info;
576         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
577         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
578         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
579         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
580         struct gfs2_holder gh;
581         struct buffer_head *m_bh, *l_bh;
582         int error;
583
584         sb_start_write(sb);
585         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
586                                    &gh);
587         if (error)
588                 goto out;
589
590         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
591         if (error)
592                 goto out_unlock;
593
594         spin_lock(&sdp->sd_statfs_spin);
595         gfs2_statfs_change_in(m_sc, m_bh->b_data +
596                               sizeof(struct gfs2_dinode));
597         if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
598                 spin_unlock(&sdp->sd_statfs_spin);
599                 goto out_bh;
600         }
601         spin_unlock(&sdp->sd_statfs_spin);
602
603         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
604         if (error)
605                 goto out_bh;
606
607         error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
608         if (error)
609                 goto out_bh2;
610
611         update_statfs(sdp, m_bh, l_bh);
612         sdp->sd_statfs_force_sync = 0;
613
614         gfs2_trans_end(sdp);
615
616 out_bh2:
617         brelse(l_bh);
618 out_bh:
619         brelse(m_bh);
620 out_unlock:
621         gfs2_glock_dq_uninit(&gh);
622 out:
623         sb_end_write(sb);
624         return error;
625 }
626
627 struct lfcc {
628         struct list_head list;
629         struct gfs2_holder gh;
630 };
631
632 /**
633  * gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
634  *                            journals are clean
635  * @sdp: the file system
636  * @state: the state to put the transaction lock into
637  * @t_gh: the hold on the transaction lock
638  *
639  * Returns: errno
640  */
641
642 static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp,
643                                     struct gfs2_holder *freeze_gh)
644 {
645         struct gfs2_inode *ip;
646         struct gfs2_jdesc *jd;
647         struct lfcc *lfcc;
648         LIST_HEAD(list);
649         struct gfs2_log_header_host lh;
650         int error;
651
652         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
653                 lfcc = kmalloc(sizeof(struct lfcc), GFP_KERNEL);
654                 if (!lfcc) {
655                         error = -ENOMEM;
656                         goto out;
657                 }
658                 ip = GFS2_I(jd->jd_inode);
659                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &lfcc->gh);
660                 if (error) {
661                         kfree(lfcc);
662                         goto out;
663                 }
664                 list_add(&lfcc->list, &list);
665         }
666
667         error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_EXCLUSIVE,
668                                    GL_NOCACHE, freeze_gh);
669
670         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
671                 error = gfs2_jdesc_check(jd);
672                 if (error)
673                         break;
674                 error = gfs2_find_jhead(jd, &lh);
675                 if (error)
676                         break;
677                 if (!(lh.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
678                         error = -EBUSY;
679                         break;
680                 }
681         }
682
683         if (error)
684                 gfs2_glock_dq_uninit(freeze_gh);
685
686 out:
687         while (!list_empty(&list)) {
688                 lfcc = list_entry(list.next, struct lfcc, list);
689                 list_del(&lfcc->list);
690                 gfs2_glock_dq_uninit(&lfcc->gh);
691                 kfree(lfcc);
692         }
693         return error;
694 }
695
696 void gfs2_dinode_out(const struct gfs2_inode *ip, void *buf)
697 {
698         struct gfs2_dinode *str = buf;
699
700         str->di_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
701         str->di_header.mh_type = cpu_to_be32(GFS2_METATYPE_DI);
702         str->di_header.mh_format = cpu_to_be32(GFS2_FORMAT_DI);
703         str->di_num.no_addr = cpu_to_be64(ip->i_no_addr);
704         str->di_num.no_formal_ino = cpu_to_be64(ip->i_no_formal_ino);
705         str->di_mode = cpu_to_be32(ip->i_inode.i_mode);
706         str->di_uid = cpu_to_be32(i_uid_read(&ip->i_inode));
707         str->di_gid = cpu_to_be32(i_gid_read(&ip->i_inode));
708         str->di_nlink = cpu_to_be32(ip->i_inode.i_nlink);
709         str->di_size = cpu_to_be64(i_size_read(&ip->i_inode));
710         str->di_blocks = cpu_to_be64(gfs2_get_inode_blocks(&ip->i_inode));
711         str->di_atime = cpu_to_be64(ip->i_inode.i_atime.tv_sec);
712         str->di_mtime = cpu_to_be64(ip->i_inode.i_mtime.tv_sec);
713         str->di_ctime = cpu_to_be64(ip->i_inode.i_ctime.tv_sec);
714
715         str->di_goal_meta = cpu_to_be64(ip->i_goal);
716         str->di_goal_data = cpu_to_be64(ip->i_goal);
717         str->di_generation = cpu_to_be64(ip->i_generation);
718
719         str->di_flags = cpu_to_be32(ip->i_diskflags);
720         str->di_height = cpu_to_be16(ip->i_height);
721         str->di_payload_format = cpu_to_be32(S_ISDIR(ip->i_inode.i_mode) &&
722                                              !(ip->i_diskflags & GFS2_DIF_EXHASH) ?
723                                              GFS2_FORMAT_DE : 0);
724         str->di_depth = cpu_to_be16(ip->i_depth);
725         str->di_entries = cpu_to_be32(ip->i_entries);
726
727         str->di_eattr = cpu_to_be64(ip->i_eattr);
728         str->di_atime_nsec = cpu_to_be32(ip->i_inode.i_atime.tv_nsec);
729         str->di_mtime_nsec = cpu_to_be32(ip->i_inode.i_mtime.tv_nsec);
730         str->di_ctime_nsec = cpu_to_be32(ip->i_inode.i_ctime.tv_nsec);
731 }
732
733 /**
734  * gfs2_write_inode - Make sure the inode is stable on the disk
735  * @inode: The inode
736  * @wbc: The writeback control structure
737  *
738  * Returns: errno
739  */
740
741 static int gfs2_write_inode(struct inode *inode, struct writeback_control *wbc)
742 {
743         struct gfs2_inode *ip = GFS2_I(inode);
744         struct gfs2_sbd *sdp = GFS2_SB(inode);
745         struct address_space *metamapping = gfs2_glock2aspace(ip->i_gl);
746         struct backing_dev_info *bdi = inode_to_bdi(metamapping->host);
747         int ret = 0;
748
749         if (wbc->sync_mode == WB_SYNC_ALL)
750                 gfs2_log_flush(GFS2_SB(inode), ip->i_gl, NORMAL_FLUSH);
751         if (bdi->dirty_exceeded)
752                 gfs2_ail1_flush(sdp, wbc);
753         else
754                 filemap_fdatawrite(metamapping);
755         if (wbc->sync_mode == WB_SYNC_ALL)
756                 ret = filemap_fdatawait(metamapping);
757         if (ret)
758                 mark_inode_dirty_sync(inode);
759         return ret;
760 }
761
762 /**
763  * gfs2_dirty_inode - check for atime updates
764  * @inode: The inode in question
765  * @flags: The type of dirty
766  *
767  * Unfortunately it can be called under any combination of inode
768  * glock and transaction lock, so we have to check carefully.
769  *
770  * At the moment this deals only with atime - it should be possible
771  * to expand that role in future, once a review of the locking has
772  * been carried out.
773  */
774
775 static void gfs2_dirty_inode(struct inode *inode, int flags)
776 {
777         struct gfs2_inode *ip = GFS2_I(inode);
778         struct gfs2_sbd *sdp = GFS2_SB(inode);
779         struct buffer_head *bh;
780         struct gfs2_holder gh;
781         int need_unlock = 0;
782         int need_endtrans = 0;
783         int ret;
784
785         if (!(flags & (I_DIRTY_DATASYNC|I_DIRTY_SYNC)))
786                 return;
787
788         if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
789                 ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
790                 if (ret) {
791                         fs_err(sdp, "dirty_inode: glock %d\n", ret);
792                         return;
793                 }
794                 need_unlock = 1;
795         } else if (WARN_ON_ONCE(ip->i_gl->gl_state != LM_ST_EXCLUSIVE))
796                 return;
797
798         if (current->journal_info == NULL) {
799                 ret = gfs2_trans_begin(sdp, RES_DINODE, 0);
800                 if (ret) {
801                         fs_err(sdp, "dirty_inode: gfs2_trans_begin %d\n", ret);
802                         goto out;
803                 }
804                 need_endtrans = 1;
805         }
806
807         ret = gfs2_meta_inode_buffer(ip, &bh);
808         if (ret == 0) {
809                 gfs2_trans_add_meta(ip->i_gl, bh);
810                 gfs2_dinode_out(ip, bh->b_data);
811                 brelse(bh);
812         }
813
814         if (need_endtrans)
815                 gfs2_trans_end(sdp);
816 out:
817         if (need_unlock)
818                 gfs2_glock_dq_uninit(&gh);
819 }
820
821 /**
822  * gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
823  * @sdp: the filesystem
824  *
825  * Returns: errno
826  */
827
828 static int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
829 {
830         struct gfs2_holder freeze_gh;
831         int error;
832
833         error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED, GL_NOCACHE,
834                                    &freeze_gh);
835         if (error && !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
836                 return error;
837
838         kthread_stop(sdp->sd_quotad_process);
839         kthread_stop(sdp->sd_logd_process);
840
841         flush_workqueue(gfs2_delete_workqueue);
842         gfs2_quota_sync(sdp->sd_vfs, 0);
843         gfs2_statfs_sync(sdp->sd_vfs, 0);
844
845         down_write(&sdp->sd_log_flush_lock);
846         clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
847         up_write(&sdp->sd_log_flush_lock);
848
849         gfs2_log_flush(sdp, NULL, SHUTDOWN_FLUSH);
850         wait_event(sdp->sd_reserving_log_wait, atomic_read(&sdp->sd_reserving_log) == 0);
851         gfs2_assert_warn(sdp, atomic_read(&sdp->sd_log_blks_free) == sdp->sd_jdesc->jd_blocks);
852
853         if (freeze_gh.gh_gl)
854                 gfs2_glock_dq_uninit(&freeze_gh);
855
856         gfs2_quota_cleanup(sdp);
857
858         return error;
859 }
860
861 /**
862  * gfs2_put_super - Unmount the filesystem
863  * @sb: The VFS superblock
864  *
865  */
866
867 static void gfs2_put_super(struct super_block *sb)
868 {
869         struct gfs2_sbd *sdp = sb->s_fs_info;
870         int error;
871         struct gfs2_jdesc *jd;
872
873         /* No more recovery requests */
874         set_bit(SDF_NORECOVERY, &sdp->sd_flags);
875         smp_mb();
876
877         /* Wait on outstanding recovery */
878 restart:
879         spin_lock(&sdp->sd_jindex_spin);
880         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
881                 if (!test_bit(JDF_RECOVERY, &jd->jd_flags))
882                         continue;
883                 spin_unlock(&sdp->sd_jindex_spin);
884                 wait_on_bit(&jd->jd_flags, JDF_RECOVERY,
885                             TASK_UNINTERRUPTIBLE);
886                 goto restart;
887         }
888         spin_unlock(&sdp->sd_jindex_spin);
889
890         if (!(sb->s_flags & MS_RDONLY)) {
891                 error = gfs2_make_fs_ro(sdp);
892                 if (error)
893                         gfs2_io_error(sdp);
894         }
895         /*  At this point, we're through modifying the disk  */
896
897         /*  Release stuff  */
898
899         iput(sdp->sd_jindex);
900         iput(sdp->sd_statfs_inode);
901         iput(sdp->sd_rindex);
902         iput(sdp->sd_quota_inode);
903
904         gfs2_glock_put(sdp->sd_rename_gl);
905         gfs2_glock_put(sdp->sd_freeze_gl);
906
907         if (!sdp->sd_args.ar_spectator) {
908                 gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
909                 gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
910                 gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
911                 gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
912                 iput(sdp->sd_sc_inode);
913                 iput(sdp->sd_qc_inode);
914         }
915
916         gfs2_glock_dq_uninit(&sdp->sd_live_gh);
917         gfs2_clear_rgrpd(sdp);
918         gfs2_jindex_free(sdp);
919         /*  Take apart glock structures and buffer lists  */
920         gfs2_gl_hash_clear(sdp);
921         /*  Unmount the locking protocol  */
922         gfs2_lm_unmount(sdp);
923
924         /*  At this point, we're through participating in the lockspace  */
925         gfs2_sys_fs_del(sdp);
926 }
927
928 /**
929  * gfs2_sync_fs - sync the filesystem
930  * @sb: the superblock
931  *
932  * Flushes the log to disk.
933  */
934
935 static int gfs2_sync_fs(struct super_block *sb, int wait)
936 {
937         struct gfs2_sbd *sdp = sb->s_fs_info;
938
939         gfs2_quota_sync(sb, -1);
940         if (wait && sdp)
941                 gfs2_log_flush(sdp, NULL, NORMAL_FLUSH);
942         return 0;
943 }
944
945 void gfs2_freeze_func(struct work_struct *work)
946 {
947         int error;
948         struct gfs2_holder freeze_gh;
949         struct gfs2_sbd *sdp = container_of(work, struct gfs2_sbd, sd_freeze_work);
950         struct super_block *sb = sdp->sd_vfs;
951
952         atomic_inc(&sb->s_active);
953         error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED, 0,
954                                    &freeze_gh);
955         if (error) {
956                 printk(KERN_INFO "GFS2: couln't get freeze lock : %d\n", error);
957                 gfs2_assert_withdraw(sdp, 0);
958         }
959         else {
960                 atomic_set(&sdp->sd_freeze_state, SFS_UNFROZEN);
961                 error = thaw_super(sb);
962                 if (error) {
963                         printk(KERN_INFO "GFS2: couldn't thaw filesystem: %d\n",
964                                error);
965                         gfs2_assert_withdraw(sdp, 0);
966                 }
967                 if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
968                         freeze_gh.gh_flags |= GL_NOCACHE;
969                 gfs2_glock_dq_uninit(&freeze_gh);
970         }
971         deactivate_super(sb);
972         return;
973 }
974
975 /**
976  * gfs2_freeze - prevent further writes to the filesystem
977  * @sb: the VFS structure for the filesystem
978  *
979  */
980
981 static int gfs2_freeze(struct super_block *sb)
982 {
983         struct gfs2_sbd *sdp = sb->s_fs_info;
984         int error = 0;
985
986         mutex_lock(&sdp->sd_freeze_mutex);
987         if (atomic_read(&sdp->sd_freeze_state) != SFS_UNFROZEN)
988                 goto out;
989
990         if (test_bit(SDF_SHUTDOWN, &sdp->sd_flags)) {
991                 error = -EINVAL;
992                 goto out;
993         }
994
995         for (;;) {
996                 error = gfs2_lock_fs_check_clean(sdp, &sdp->sd_freeze_gh);
997                 if (!error)
998                         break;
999
1000                 switch (error) {
1001                 case -EBUSY:
1002                         fs_err(sdp, "waiting for recovery before freeze\n");
1003                         break;
1004
1005                 default:
1006                         fs_err(sdp, "error freezing FS: %d\n", error);
1007                         break;
1008                 }
1009
1010                 fs_err(sdp, "retrying...\n");
1011                 msleep(1000);
1012         }
1013         error = 0;
1014 out:
1015         mutex_unlock(&sdp->sd_freeze_mutex);
1016         return error;
1017 }
1018
1019 /**
1020  * gfs2_unfreeze - reallow writes to the filesystem
1021  * @sb: the VFS structure for the filesystem
1022  *
1023  */
1024
1025 static int gfs2_unfreeze(struct super_block *sb)
1026 {
1027         struct gfs2_sbd *sdp = sb->s_fs_info;
1028
1029         mutex_lock(&sdp->sd_freeze_mutex);
1030         if (atomic_read(&sdp->sd_freeze_state) != SFS_FROZEN ||
1031             sdp->sd_freeze_gh.gh_gl == NULL) {
1032                 mutex_unlock(&sdp->sd_freeze_mutex);
1033                 return 0;
1034         }
1035
1036         gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
1037         mutex_unlock(&sdp->sd_freeze_mutex);
1038         return 0;
1039 }
1040
1041 /**
1042  * statfs_fill - fill in the sg for a given RG
1043  * @rgd: the RG
1044  * @sc: the sc structure
1045  *
1046  * Returns: 0 on success, -ESTALE if the LVB is invalid
1047  */
1048
1049 static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
1050                             struct gfs2_statfs_change_host *sc)
1051 {
1052         gfs2_rgrp_verify(rgd);
1053         sc->sc_total += rgd->rd_data;
1054         sc->sc_free += rgd->rd_free;
1055         sc->sc_dinodes += rgd->rd_dinodes;
1056         return 0;
1057 }
1058
1059 /**
1060  * gfs2_statfs_slow - Stat a filesystem using asynchronous locking
1061  * @sdp: the filesystem
1062  * @sc: the sc info that will be returned
1063  *
1064  * Any error (other than a signal) will cause this routine to fall back
1065  * to the synchronous version.
1066  *
1067  * FIXME: This really shouldn't busy wait like this.
1068  *
1069  * Returns: errno
1070  */
1071
1072 static int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
1073 {
1074         struct gfs2_rgrpd *rgd_next;
1075         struct gfs2_holder *gha, *gh;
1076         unsigned int slots = 64;
1077         unsigned int x;
1078         int done;
1079         int error = 0, err;
1080
1081         memset(sc, 0, sizeof(struct gfs2_statfs_change_host));
1082         gha = kcalloc(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
1083         if (!gha)
1084                 return -ENOMEM;
1085
1086         rgd_next = gfs2_rgrpd_get_first(sdp);
1087
1088         for (;;) {
1089                 done = 1;
1090
1091                 for (x = 0; x < slots; x++) {
1092                         gh = gha + x;
1093
1094                         if (gh->gh_gl && gfs2_glock_poll(gh)) {
1095                                 err = gfs2_glock_wait(gh);
1096                                 if (err) {
1097                                         gfs2_holder_uninit(gh);
1098                                         error = err;
1099                                 } else {
1100                                         if (!error)
1101                                                 error = statfs_slow_fill(
1102                                                         gh->gh_gl->gl_object, sc);
1103                                         gfs2_glock_dq_uninit(gh);
1104                                 }
1105                         }
1106
1107                         if (gh->gh_gl)
1108                                 done = 0;
1109                         else if (rgd_next && !error) {
1110                                 error = gfs2_glock_nq_init(rgd_next->rd_gl,
1111                                                            LM_ST_SHARED,
1112                                                            GL_ASYNC,
1113                                                            gh);
1114                                 rgd_next = gfs2_rgrpd_get_next(rgd_next);
1115                                 done = 0;
1116                         }
1117
1118                         if (signal_pending(current))
1119                                 error = -ERESTARTSYS;
1120                 }
1121
1122                 if (done)
1123                         break;
1124
1125                 yield();
1126         }
1127
1128         kfree(gha);
1129         return error;
1130 }
1131
1132 /**
1133  * gfs2_statfs_i - Do a statfs
1134  * @sdp: the filesystem
1135  * @sg: the sg structure
1136  *
1137  * Returns: errno
1138  */
1139
1140 static int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
1141 {
1142         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
1143         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
1144
1145         spin_lock(&sdp->sd_statfs_spin);
1146
1147         *sc = *m_sc;
1148         sc->sc_total += l_sc->sc_total;
1149         sc->sc_free += l_sc->sc_free;
1150         sc->sc_dinodes += l_sc->sc_dinodes;
1151
1152         spin_unlock(&sdp->sd_statfs_spin);
1153
1154         if (sc->sc_free < 0)
1155                 sc->sc_free = 0;
1156         if (sc->sc_free > sc->sc_total)
1157                 sc->sc_free = sc->sc_total;
1158         if (sc->sc_dinodes < 0)
1159                 sc->sc_dinodes = 0;
1160
1161         return 0;
1162 }
1163
1164 /**
1165  * gfs2_statfs - Gather and return stats about the filesystem
1166  * @sb: The superblock
1167  * @statfsbuf: The buffer
1168  *
1169  * Returns: 0 on success or error code
1170  */
1171
1172 static int gfs2_statfs(struct dentry *dentry, struct kstatfs *buf)
1173 {
1174         struct super_block *sb = d_inode(dentry)->i_sb;
1175         struct gfs2_sbd *sdp = sb->s_fs_info;
1176         struct gfs2_statfs_change_host sc;
1177         int error;
1178
1179         error = gfs2_rindex_update(sdp);
1180         if (error)
1181                 return error;
1182
1183         if (gfs2_tune_get(sdp, gt_statfs_slow))
1184                 error = gfs2_statfs_slow(sdp, &sc);
1185         else
1186                 error = gfs2_statfs_i(sdp, &sc);
1187
1188         if (error)
1189                 return error;
1190
1191         buf->f_type = GFS2_MAGIC;
1192         buf->f_bsize = sdp->sd_sb.sb_bsize;
1193         buf->f_blocks = sc.sc_total;
1194         buf->f_bfree = sc.sc_free;
1195         buf->f_bavail = sc.sc_free;
1196         buf->f_files = sc.sc_dinodes + sc.sc_free;
1197         buf->f_ffree = sc.sc_free;
1198         buf->f_namelen = GFS2_FNAMESIZE;
1199
1200         return 0;
1201 }
1202
1203 /**
1204  * gfs2_remount_fs - called when the FS is remounted
1205  * @sb:  the filesystem
1206  * @flags:  the remount flags
1207  * @data:  extra data passed in (not used right now)
1208  *
1209  * Returns: errno
1210  */
1211
1212 static int gfs2_remount_fs(struct super_block *sb, int *flags, char *data)
1213 {
1214         struct gfs2_sbd *sdp = sb->s_fs_info;
1215         struct gfs2_args args = sdp->sd_args; /* Default to current settings */
1216         struct gfs2_tune *gt = &sdp->sd_tune;
1217         int error;
1218
1219         sync_filesystem(sb);
1220
1221         spin_lock(&gt->gt_spin);
1222         args.ar_commit = gt->gt_logd_secs;
1223         args.ar_quota_quantum = gt->gt_quota_quantum;
1224         if (gt->gt_statfs_slow)
1225                 args.ar_statfs_quantum = 0;
1226         else
1227                 args.ar_statfs_quantum = gt->gt_statfs_quantum;
1228         spin_unlock(&gt->gt_spin);
1229         error = gfs2_mount_args(&args, data);
1230         if (error)
1231                 return error;
1232
1233         /* Not allowed to change locking details */
1234         if (strcmp(args.ar_lockproto, sdp->sd_args.ar_lockproto) ||
1235             strcmp(args.ar_locktable, sdp->sd_args.ar_locktable) ||
1236             strcmp(args.ar_hostdata, sdp->sd_args.ar_hostdata))
1237                 return -EINVAL;
1238
1239         /* Some flags must not be changed */
1240         if (args_neq(&args, &sdp->sd_args, spectator) ||
1241             args_neq(&args, &sdp->sd_args, localflocks) ||
1242             args_neq(&args, &sdp->sd_args, meta))
1243                 return -EINVAL;
1244
1245         if (sdp->sd_args.ar_spectator)
1246                 *flags |= MS_RDONLY;
1247
1248         if ((sb->s_flags ^ *flags) & MS_RDONLY) {
1249                 if (*flags & MS_RDONLY)
1250                         error = gfs2_make_fs_ro(sdp);
1251                 else
1252                         error = gfs2_make_fs_rw(sdp);
1253                 if (error)
1254                         return error;
1255         }
1256
1257         sdp->sd_args = args;
1258         if (sdp->sd_args.ar_posix_acl)
1259                 sb->s_flags |= MS_POSIXACL;
1260         else
1261                 sb->s_flags &= ~MS_POSIXACL;
1262         if (sdp->sd_args.ar_nobarrier)
1263                 set_bit(SDF_NOBARRIERS, &sdp->sd_flags);
1264         else
1265                 clear_bit(SDF_NOBARRIERS, &sdp->sd_flags);
1266         spin_lock(&gt->gt_spin);
1267         gt->gt_logd_secs = args.ar_commit;
1268         gt->gt_quota_quantum = args.ar_quota_quantum;
1269         if (args.ar_statfs_quantum) {
1270                 gt->gt_statfs_slow = 0;
1271                 gt->gt_statfs_quantum = args.ar_statfs_quantum;
1272         }
1273         else {
1274                 gt->gt_statfs_slow = 1;
1275                 gt->gt_statfs_quantum = 30;
1276         }
1277         spin_unlock(&gt->gt_spin);
1278
1279         gfs2_online_uevent(sdp);
1280         return 0;
1281 }
1282
1283 /**
1284  * gfs2_drop_inode - Drop an inode (test for remote unlink)
1285  * @inode: The inode to drop
1286  *
1287  * If we've received a callback on an iopen lock then its because a
1288  * remote node tried to deallocate the inode but failed due to this node
1289  * still having the inode open. Here we mark the link count zero
1290  * since we know that it must have reached zero if the GLF_DEMOTE flag
1291  * is set on the iopen glock. If we didn't do a disk read since the
1292  * remote node removed the final link then we might otherwise miss
1293  * this event. This check ensures that this node will deallocate the
1294  * inode's blocks, or alternatively pass the baton on to another
1295  * node for later deallocation.
1296  */
1297
1298 static int gfs2_drop_inode(struct inode *inode)
1299 {
1300         struct gfs2_inode *ip = GFS2_I(inode);
1301
1302         if (!test_bit(GIF_FREE_VFS_INODE, &ip->i_flags) && inode->i_nlink) {
1303                 struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
1304                 if (gl && test_bit(GLF_DEMOTE, &gl->gl_flags))
1305                         clear_nlink(inode);
1306         }
1307         return generic_drop_inode(inode);
1308 }
1309
1310 static int is_ancestor(const struct dentry *d1, const struct dentry *d2)
1311 {
1312         do {
1313                 if (d1 == d2)
1314                         return 1;
1315                 d1 = d1->d_parent;
1316         } while (!IS_ROOT(d1));
1317         return 0;
1318 }
1319
1320 /**
1321  * gfs2_show_options - Show mount options for /proc/mounts
1322  * @s: seq_file structure
1323  * @root: root of this (sub)tree
1324  *
1325  * Returns: 0 on success or error code
1326  */
1327
1328 static int gfs2_show_options(struct seq_file *s, struct dentry *root)
1329 {
1330         struct gfs2_sbd *sdp = root->d_sb->s_fs_info;
1331         struct gfs2_args *args = &sdp->sd_args;
1332         int val;
1333
1334         if (is_ancestor(root, sdp->sd_master_dir))
1335                 seq_puts(s, ",meta");
1336         if (args->ar_lockproto[0])
1337                 seq_show_option(s, "lockproto", args->ar_lockproto);
1338         if (args->ar_locktable[0])
1339                 seq_show_option(s, "locktable", args->ar_locktable);
1340         if (args->ar_hostdata[0])
1341                 seq_show_option(s, "hostdata", args->ar_hostdata);
1342         if (args->ar_spectator)
1343                 seq_puts(s, ",spectator");
1344         if (args->ar_localflocks)
1345                 seq_puts(s, ",localflocks");
1346         if (args->ar_debug)
1347                 seq_puts(s, ",debug");
1348         if (args->ar_posix_acl)
1349                 seq_puts(s, ",acl");
1350         if (args->ar_quota != GFS2_QUOTA_DEFAULT) {
1351                 char *state;
1352                 switch (args->ar_quota) {
1353                 case GFS2_QUOTA_OFF:
1354                         state = "off";
1355                         break;
1356                 case GFS2_QUOTA_ACCOUNT:
1357                         state = "account";
1358                         break;
1359                 case GFS2_QUOTA_ON:
1360                         state = "on";
1361                         break;
1362                 default:
1363                         state = "unknown";
1364                         break;
1365                 }
1366                 seq_printf(s, ",quota=%s", state);
1367         }
1368         if (args->ar_suiddir)
1369                 seq_puts(s, ",suiddir");
1370         if (args->ar_data != GFS2_DATA_DEFAULT) {
1371                 char *state;
1372                 switch (args->ar_data) {
1373                 case GFS2_DATA_WRITEBACK:
1374                         state = "writeback";
1375                         break;
1376                 case GFS2_DATA_ORDERED:
1377                         state = "ordered";
1378                         break;
1379                 default:
1380                         state = "unknown";
1381                         break;
1382                 }
1383                 seq_printf(s, ",data=%s", state);
1384         }
1385         if (args->ar_discard)
1386                 seq_puts(s, ",discard");
1387         val = sdp->sd_tune.gt_logd_secs;
1388         if (val != 30)
1389                 seq_printf(s, ",commit=%d", val);
1390         val = sdp->sd_tune.gt_statfs_quantum;
1391         if (val != 30)
1392                 seq_printf(s, ",statfs_quantum=%d", val);
1393         else if (sdp->sd_tune.gt_statfs_slow)
1394                 seq_puts(s, ",statfs_quantum=0");
1395         val = sdp->sd_tune.gt_quota_quantum;
1396         if (val != 60)
1397                 seq_printf(s, ",quota_quantum=%d", val);
1398         if (args->ar_statfs_percent)
1399                 seq_printf(s, ",statfs_percent=%d", args->ar_statfs_percent);
1400         if (args->ar_errors != GFS2_ERRORS_DEFAULT) {
1401                 const char *state;
1402
1403                 switch (args->ar_errors) {
1404                 case GFS2_ERRORS_WITHDRAW:
1405                         state = "withdraw";
1406                         break;
1407                 case GFS2_ERRORS_PANIC:
1408                         state = "panic";
1409                         break;
1410                 default:
1411                         state = "unknown";
1412                         break;
1413                 }
1414                 seq_printf(s, ",errors=%s", state);
1415         }
1416         if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags))
1417                 seq_puts(s, ",nobarrier");
1418         if (test_bit(SDF_DEMOTE, &sdp->sd_flags))
1419                 seq_puts(s, ",demote_interface_used");
1420         if (args->ar_rgrplvb)
1421                 seq_puts(s, ",rgrplvb");
1422         return 0;
1423 }
1424
1425 static void gfs2_final_release_pages(struct gfs2_inode *ip)
1426 {
1427         struct inode *inode = &ip->i_inode;
1428         struct gfs2_glock *gl = ip->i_gl;
1429
1430         truncate_inode_pages(gfs2_glock2aspace(ip->i_gl), 0);
1431         truncate_inode_pages(&inode->i_data, 0);
1432
1433         if (atomic_read(&gl->gl_revokes) == 0) {
1434                 clear_bit(GLF_LFLUSH, &gl->gl_flags);
1435                 clear_bit(GLF_DIRTY, &gl->gl_flags);
1436         }
1437 }
1438
1439 static int gfs2_dinode_dealloc(struct gfs2_inode *ip)
1440 {
1441         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1442         struct gfs2_rgrpd *rgd;
1443         struct gfs2_holder gh;
1444         int error;
1445
1446         if (gfs2_get_inode_blocks(&ip->i_inode) != 1) {
1447                 gfs2_consist_inode(ip);
1448                 return -EIO;
1449         }
1450
1451         error = gfs2_rindex_update(sdp);
1452         if (error)
1453                 return error;
1454
1455         error = gfs2_quota_hold(ip, NO_UID_QUOTA_CHANGE, NO_GID_QUOTA_CHANGE);
1456         if (error)
1457                 return error;
1458
1459         rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr, 1);
1460         if (!rgd) {
1461                 gfs2_consist_inode(ip);
1462                 error = -EIO;
1463                 goto out_qs;
1464         }
1465
1466         error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, &gh);
1467         if (error)
1468                 goto out_qs;
1469
1470         error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_STATFS + RES_QUOTA,
1471                                  sdp->sd_jdesc->jd_blocks);
1472         if (error)
1473                 goto out_rg_gunlock;
1474
1475         gfs2_free_di(rgd, ip);
1476
1477         gfs2_final_release_pages(ip);
1478
1479         gfs2_trans_end(sdp);
1480
1481 out_rg_gunlock:
1482         gfs2_glock_dq_uninit(&gh);
1483 out_qs:
1484         gfs2_quota_unhold(ip);
1485         return error;
1486 }
1487
1488 /**
1489  * gfs2_evict_inode - Remove an inode from cache
1490  * @inode: The inode to evict
1491  *
1492  * There are three cases to consider:
1493  * 1. i_nlink == 0, we are final opener (and must deallocate)
1494  * 2. i_nlink == 0, we are not the final opener (and cannot deallocate)
1495  * 3. i_nlink > 0
1496  *
1497  * If the fs is read only, then we have to treat all cases as per #3
1498  * since we are unable to do any deallocation. The inode will be
1499  * deallocated by the next read/write node to attempt an allocation
1500  * in the same resource group
1501  *
1502  * We have to (at the moment) hold the inodes main lock to cover
1503  * the gap between unlocking the shared lock on the iopen lock and
1504  * taking the exclusive lock. I'd rather do a shared -> exclusive
1505  * conversion on the iopen lock, but we can change that later. This
1506  * is safe, just less efficient.
1507  */
1508
1509 static void gfs2_evict_inode(struct inode *inode)
1510 {
1511         struct super_block *sb = inode->i_sb;
1512         struct gfs2_sbd *sdp = sb->s_fs_info;
1513         struct gfs2_inode *ip = GFS2_I(inode);
1514         struct gfs2_holder gh;
1515         int error;
1516
1517         if (test_bit(GIF_FREE_VFS_INODE, &ip->i_flags)) {
1518                 clear_inode(inode);
1519                 return;
1520         }
1521
1522         if (inode->i_nlink || (sb->s_flags & MS_RDONLY))
1523                 goto out;
1524
1525         /* Must not read inode block until block type has been verified */
1526         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, &gh);
1527         if (unlikely(error)) {
1528                 ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1529                 gfs2_glock_dq_uninit(&ip->i_iopen_gh);
1530                 goto out;
1531         }
1532
1533         if (!test_bit(GIF_ALLOC_FAILED, &ip->i_flags)) {
1534                 error = gfs2_check_blk_type(sdp, ip->i_no_addr, GFS2_BLKST_UNLINKED);
1535                 if (error)
1536                         goto out_truncate;
1537         }
1538
1539         if (test_bit(GIF_INVALID, &ip->i_flags)) {
1540                 error = gfs2_inode_refresh(ip);
1541                 if (error)
1542                         goto out_truncate;
1543         }
1544
1545         ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1546         gfs2_glock_dq_wait(&ip->i_iopen_gh);
1547         gfs2_holder_reinit(LM_ST_EXCLUSIVE, LM_FLAG_TRY_1CB | GL_NOCACHE, &ip->i_iopen_gh);
1548         error = gfs2_glock_nq(&ip->i_iopen_gh);
1549         if (error)
1550                 goto out_truncate;
1551
1552         /* Case 1 starts here */
1553
1554         if (S_ISDIR(inode->i_mode) &&
1555             (ip->i_diskflags & GFS2_DIF_EXHASH)) {
1556                 error = gfs2_dir_exhash_dealloc(ip);
1557                 if (error)
1558                         goto out_unlock;
1559         }
1560
1561         if (ip->i_eattr) {
1562                 error = gfs2_ea_dealloc(ip);
1563                 if (error)
1564                         goto out_unlock;
1565         }
1566
1567         if (!gfs2_is_stuffed(ip)) {
1568                 error = gfs2_file_dealloc(ip);
1569                 if (error)
1570                         goto out_unlock;
1571         }
1572
1573         error = gfs2_dinode_dealloc(ip);
1574         goto out_unlock;
1575
1576 out_truncate:
1577         gfs2_log_flush(sdp, ip->i_gl, NORMAL_FLUSH);
1578         if (test_bit(GLF_DIRTY, &ip->i_gl->gl_flags)) {
1579                 struct address_space *metamapping = gfs2_glock2aspace(ip->i_gl);
1580                 filemap_fdatawrite(metamapping);
1581                 filemap_fdatawait(metamapping);
1582         }
1583         write_inode_now(inode, 1);
1584         gfs2_ail_flush(ip->i_gl, 0);
1585
1586         /* Case 2 starts here */
1587         error = gfs2_trans_begin(sdp, 0, sdp->sd_jdesc->jd_blocks);
1588         if (error)
1589                 goto out_unlock;
1590         /* Needs to be done before glock release & also in a transaction */
1591         truncate_inode_pages(&inode->i_data, 0);
1592         gfs2_trans_end(sdp);
1593
1594 out_unlock:
1595         /* Error path for case 1 */
1596         if (gfs2_rs_active(ip->i_res))
1597                 gfs2_rs_deltree(ip->i_res);
1598
1599         if (test_bit(HIF_HOLDER, &ip->i_iopen_gh.gh_iflags)) {
1600                 ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1601                 gfs2_glock_dq(&ip->i_iopen_gh);
1602         }
1603         gfs2_holder_uninit(&ip->i_iopen_gh);
1604         gfs2_glock_dq_uninit(&gh);
1605         if (error && error != GLR_TRYFAILED && error != -EROFS)
1606                 fs_warn(sdp, "gfs2_evict_inode: %d\n", error);
1607 out:
1608         /* Case 3 starts here */
1609         truncate_inode_pages_final(&inode->i_data);
1610         gfs2_rs_delete(ip, NULL);
1611         gfs2_ordered_del_inode(ip);
1612         clear_inode(inode);
1613         gfs2_dir_hash_inval(ip);
1614         ip->i_gl->gl_object = NULL;
1615         flush_delayed_work(&ip->i_gl->gl_work);
1616         gfs2_glock_add_to_lru(ip->i_gl);
1617         gfs2_glock_put(ip->i_gl);
1618         ip->i_gl = NULL;
1619         if (ip->i_iopen_gh.gh_gl) {
1620                 ip->i_iopen_gh.gh_gl->gl_object = NULL;
1621                 ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1622                 gfs2_glock_dq_uninit(&ip->i_iopen_gh);
1623         }
1624 }
1625
1626 static struct inode *gfs2_alloc_inode(struct super_block *sb)
1627 {
1628         struct gfs2_inode *ip;
1629
1630         ip = kmem_cache_alloc(gfs2_inode_cachep, GFP_KERNEL);
1631         if (ip) {
1632                 ip->i_flags = 0;
1633                 ip->i_gl = NULL;
1634                 ip->i_rgd = NULL;
1635                 ip->i_res = NULL;
1636         }
1637         return &ip->i_inode;
1638 }
1639
1640 static void gfs2_i_callback(struct rcu_head *head)
1641 {
1642         struct inode *inode = container_of(head, struct inode, i_rcu);
1643         kmem_cache_free(gfs2_inode_cachep, inode);
1644 }
1645
1646 static void gfs2_destroy_inode(struct inode *inode)
1647 {
1648         call_rcu(&inode->i_rcu, gfs2_i_callback);
1649 }
1650
1651 const struct super_operations gfs2_super_ops = {
1652         .alloc_inode            = gfs2_alloc_inode,
1653         .destroy_inode          = gfs2_destroy_inode,
1654         .write_inode            = gfs2_write_inode,
1655         .dirty_inode            = gfs2_dirty_inode,
1656         .evict_inode            = gfs2_evict_inode,
1657         .put_super              = gfs2_put_super,
1658         .sync_fs                = gfs2_sync_fs,
1659         .freeze_super           = gfs2_freeze,
1660         .thaw_super             = gfs2_unfreeze,
1661         .statfs                 = gfs2_statfs,
1662         .remount_fs             = gfs2_remount_fs,
1663         .drop_inode             = gfs2_drop_inode,
1664         .show_options           = gfs2_show_options,
1665 };
1666