xref: /openbmc/linux/fs/gfs2/super.c (revision 22fd411a)
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 
27 #include "gfs2.h"
28 #include "incore.h"
29 #include "bmap.h"
30 #include "dir.h"
31 #include "glock.h"
32 #include "glops.h"
33 #include "inode.h"
34 #include "log.h"
35 #include "meta_io.h"
36 #include "quota.h"
37 #include "recovery.h"
38 #include "rgrp.h"
39 #include "super.h"
40 #include "trans.h"
41 #include "util.h"
42 #include "sys.h"
43 #include "xattr.h"
44 
45 #define args_neq(a1, a2, x) ((a1)->ar_##x != (a2)->ar_##x)
46 
47 enum {
48 	Opt_lockproto,
49 	Opt_locktable,
50 	Opt_hostdata,
51 	Opt_spectator,
52 	Opt_ignore_local_fs,
53 	Opt_localflocks,
54 	Opt_localcaching,
55 	Opt_debug,
56 	Opt_nodebug,
57 	Opt_upgrade,
58 	Opt_acl,
59 	Opt_noacl,
60 	Opt_quota_off,
61 	Opt_quota_account,
62 	Opt_quota_on,
63 	Opt_quota,
64 	Opt_noquota,
65 	Opt_suiddir,
66 	Opt_nosuiddir,
67 	Opt_data_writeback,
68 	Opt_data_ordered,
69 	Opt_meta,
70 	Opt_discard,
71 	Opt_nodiscard,
72 	Opt_commit,
73 	Opt_err_withdraw,
74 	Opt_err_panic,
75 	Opt_statfs_quantum,
76 	Opt_statfs_percent,
77 	Opt_quota_quantum,
78 	Opt_barrier,
79 	Opt_nobarrier,
80 	Opt_error,
81 };
82 
83 static const match_table_t tokens = {
84 	{Opt_lockproto, "lockproto=%s"},
85 	{Opt_locktable, "locktable=%s"},
86 	{Opt_hostdata, "hostdata=%s"},
87 	{Opt_spectator, "spectator"},
88 	{Opt_spectator, "norecovery"},
89 	{Opt_ignore_local_fs, "ignore_local_fs"},
90 	{Opt_localflocks, "localflocks"},
91 	{Opt_localcaching, "localcaching"},
92 	{Opt_debug, "debug"},
93 	{Opt_nodebug, "nodebug"},
94 	{Opt_upgrade, "upgrade"},
95 	{Opt_acl, "acl"},
96 	{Opt_noacl, "noacl"},
97 	{Opt_quota_off, "quota=off"},
98 	{Opt_quota_account, "quota=account"},
99 	{Opt_quota_on, "quota=on"},
100 	{Opt_quota, "quota"},
101 	{Opt_noquota, "noquota"},
102 	{Opt_suiddir, "suiddir"},
103 	{Opt_nosuiddir, "nosuiddir"},
104 	{Opt_data_writeback, "data=writeback"},
105 	{Opt_data_ordered, "data=ordered"},
106 	{Opt_meta, "meta"},
107 	{Opt_discard, "discard"},
108 	{Opt_nodiscard, "nodiscard"},
109 	{Opt_commit, "commit=%d"},
110 	{Opt_err_withdraw, "errors=withdraw"},
111 	{Opt_err_panic, "errors=panic"},
112 	{Opt_statfs_quantum, "statfs_quantum=%d"},
113 	{Opt_statfs_percent, "statfs_percent=%d"},
114 	{Opt_quota_quantum, "quota_quantum=%d"},
115 	{Opt_barrier, "barrier"},
116 	{Opt_nobarrier, "nobarrier"},
117 	{Opt_error, NULL}
118 };
119 
120 /**
121  * gfs2_mount_args - Parse mount options
122  * @args: The structure into which the parsed options will be written
123  * @options: The options to parse
124  *
125  * Return: errno
126  */
127 
128 int gfs2_mount_args(struct gfs2_args *args, char *options)
129 {
130 	char *o;
131 	int token;
132 	substring_t tmp[MAX_OPT_ARGS];
133 	int rv;
134 
135 	/* Split the options into tokens with the "," character and
136 	   process them */
137 
138 	while (1) {
139 		o = strsep(&options, ",");
140 		if (o == NULL)
141 			break;
142 		if (*o == '\0')
143 			continue;
144 
145 		token = match_token(o, tokens, tmp);
146 		switch (token) {
147 		case Opt_lockproto:
148 			match_strlcpy(args->ar_lockproto, &tmp[0],
149 				      GFS2_LOCKNAME_LEN);
150 			break;
151 		case Opt_locktable:
152 			match_strlcpy(args->ar_locktable, &tmp[0],
153 				      GFS2_LOCKNAME_LEN);
154 			break;
155 		case Opt_hostdata:
156 			match_strlcpy(args->ar_hostdata, &tmp[0],
157 				      GFS2_LOCKNAME_LEN);
158 			break;
159 		case Opt_spectator:
160 			args->ar_spectator = 1;
161 			break;
162 		case Opt_ignore_local_fs:
163 			/* Retained for backwards compat only */
164 			break;
165 		case Opt_localflocks:
166 			args->ar_localflocks = 1;
167 			break;
168 		case Opt_localcaching:
169 			/* Retained for backwards compat only */
170 			break;
171 		case Opt_debug:
172 			if (args->ar_errors == GFS2_ERRORS_PANIC) {
173 				printk(KERN_WARNING "GFS2: -o debug and -o errors=panic "
174 				       "are mutually exclusive.\n");
175 				return -EINVAL;
176 			}
177 			args->ar_debug = 1;
178 			break;
179 		case Opt_nodebug:
180 			args->ar_debug = 0;
181 			break;
182 		case Opt_upgrade:
183 			/* Retained for backwards compat only */
184 			break;
185 		case Opt_acl:
186 			args->ar_posix_acl = 1;
187 			break;
188 		case Opt_noacl:
189 			args->ar_posix_acl = 0;
190 			break;
191 		case Opt_quota_off:
192 		case Opt_noquota:
193 			args->ar_quota = GFS2_QUOTA_OFF;
194 			break;
195 		case Opt_quota_account:
196 			args->ar_quota = GFS2_QUOTA_ACCOUNT;
197 			break;
198 		case Opt_quota_on:
199 		case Opt_quota:
200 			args->ar_quota = GFS2_QUOTA_ON;
201 			break;
202 		case Opt_suiddir:
203 			args->ar_suiddir = 1;
204 			break;
205 		case Opt_nosuiddir:
206 			args->ar_suiddir = 0;
207 			break;
208 		case Opt_data_writeback:
209 			args->ar_data = GFS2_DATA_WRITEBACK;
210 			break;
211 		case Opt_data_ordered:
212 			args->ar_data = GFS2_DATA_ORDERED;
213 			break;
214 		case Opt_meta:
215 			args->ar_meta = 1;
216 			break;
217 		case Opt_discard:
218 			args->ar_discard = 1;
219 			break;
220 		case Opt_nodiscard:
221 			args->ar_discard = 0;
222 			break;
223 		case Opt_commit:
224 			rv = match_int(&tmp[0], &args->ar_commit);
225 			if (rv || args->ar_commit <= 0) {
226 				printk(KERN_WARNING "GFS2: commit mount option requires a positive numeric argument\n");
227 				return rv ? rv : -EINVAL;
228 			}
229 			break;
230 		case Opt_statfs_quantum:
231 			rv = match_int(&tmp[0], &args->ar_statfs_quantum);
232 			if (rv || args->ar_statfs_quantum < 0) {
233 				printk(KERN_WARNING "GFS2: statfs_quantum mount option requires a non-negative numeric argument\n");
234 				return rv ? rv : -EINVAL;
235 			}
236 			break;
237 		case Opt_quota_quantum:
238 			rv = match_int(&tmp[0], &args->ar_quota_quantum);
239 			if (rv || args->ar_quota_quantum <= 0) {
240 				printk(KERN_WARNING "GFS2: quota_quantum mount option requires a positive numeric argument\n");
241 				return rv ? rv : -EINVAL;
242 			}
243 			break;
244 		case Opt_statfs_percent:
245 			rv = match_int(&tmp[0], &args->ar_statfs_percent);
246 			if (rv || args->ar_statfs_percent < 0 ||
247 			    args->ar_statfs_percent > 100) {
248 				printk(KERN_WARNING "statfs_percent mount option requires a numeric argument between 0 and 100\n");
249 				return rv ? rv : -EINVAL;
250 			}
251 			break;
252 		case Opt_err_withdraw:
253 			args->ar_errors = GFS2_ERRORS_WITHDRAW;
254 			break;
255 		case Opt_err_panic:
256 			if (args->ar_debug) {
257 				printk(KERN_WARNING "GFS2: -o debug and -o errors=panic "
258 					"are mutually exclusive.\n");
259 				return -EINVAL;
260 			}
261 			args->ar_errors = GFS2_ERRORS_PANIC;
262 			break;
263 		case Opt_barrier:
264 			args->ar_nobarrier = 0;
265 			break;
266 		case Opt_nobarrier:
267 			args->ar_nobarrier = 1;
268 			break;
269 		case Opt_error:
270 		default:
271 			printk(KERN_WARNING "GFS2: invalid mount option: %s\n", o);
272 			return -EINVAL;
273 		}
274 	}
275 
276 	return 0;
277 }
278 
279 /**
280  * gfs2_jindex_free - Clear all the journal index information
281  * @sdp: The GFS2 superblock
282  *
283  */
284 
285 void gfs2_jindex_free(struct gfs2_sbd *sdp)
286 {
287 	struct list_head list, *head;
288 	struct gfs2_jdesc *jd;
289 	struct gfs2_journal_extent *jext;
290 
291 	spin_lock(&sdp->sd_jindex_spin);
292 	list_add(&list, &sdp->sd_jindex_list);
293 	list_del_init(&sdp->sd_jindex_list);
294 	sdp->sd_journals = 0;
295 	spin_unlock(&sdp->sd_jindex_spin);
296 
297 	while (!list_empty(&list)) {
298 		jd = list_entry(list.next, struct gfs2_jdesc, jd_list);
299 		head = &jd->extent_list;
300 		while (!list_empty(head)) {
301 			jext = list_entry(head->next,
302 					  struct gfs2_journal_extent,
303 					  extent_list);
304 			list_del(&jext->extent_list);
305 			kfree(jext);
306 		}
307 		list_del(&jd->jd_list);
308 		iput(jd->jd_inode);
309 		kfree(jd);
310 	}
311 }
312 
313 static struct gfs2_jdesc *jdesc_find_i(struct list_head *head, unsigned int jid)
314 {
315 	struct gfs2_jdesc *jd;
316 	int found = 0;
317 
318 	list_for_each_entry(jd, head, jd_list) {
319 		if (jd->jd_jid == jid) {
320 			found = 1;
321 			break;
322 		}
323 	}
324 
325 	if (!found)
326 		jd = NULL;
327 
328 	return jd;
329 }
330 
331 struct gfs2_jdesc *gfs2_jdesc_find(struct gfs2_sbd *sdp, unsigned int jid)
332 {
333 	struct gfs2_jdesc *jd;
334 
335 	spin_lock(&sdp->sd_jindex_spin);
336 	jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
337 	spin_unlock(&sdp->sd_jindex_spin);
338 
339 	return jd;
340 }
341 
342 int gfs2_jdesc_check(struct gfs2_jdesc *jd)
343 {
344 	struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
345 	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
346 	u64 size = i_size_read(jd->jd_inode);
347 
348 	if (gfs2_check_internal_file_size(jd->jd_inode, 8 << 20, 1 << 30))
349 		return -EIO;
350 
351 	jd->jd_blocks = size >> sdp->sd_sb.sb_bsize_shift;
352 
353 	if (gfs2_write_alloc_required(ip, 0, size)) {
354 		gfs2_consist_inode(ip);
355 		return -EIO;
356 	}
357 
358 	return 0;
359 }
360 
361 /**
362  * gfs2_make_fs_rw - Turn a Read-Only FS into a Read-Write one
363  * @sdp: the filesystem
364  *
365  * Returns: errno
366  */
367 
368 int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
369 {
370 	struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
371 	struct gfs2_glock *j_gl = ip->i_gl;
372 	struct gfs2_holder t_gh;
373 	struct gfs2_log_header_host head;
374 	int error;
375 
376 	error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED, 0, &t_gh);
377 	if (error)
378 		return error;
379 
380 	j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
381 
382 	error = gfs2_find_jhead(sdp->sd_jdesc, &head);
383 	if (error)
384 		goto fail;
385 
386 	if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
387 		gfs2_consist(sdp);
388 		error = -EIO;
389 		goto fail;
390 	}
391 
392 	/*  Initialize some head of the log stuff  */
393 	sdp->sd_log_sequence = head.lh_sequence + 1;
394 	gfs2_log_pointers_init(sdp, head.lh_blkno);
395 
396 	error = gfs2_quota_init(sdp);
397 	if (error)
398 		goto fail;
399 
400 	set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
401 
402 	gfs2_glock_dq_uninit(&t_gh);
403 
404 	return 0;
405 
406 fail:
407 	t_gh.gh_flags |= GL_NOCACHE;
408 	gfs2_glock_dq_uninit(&t_gh);
409 
410 	return error;
411 }
412 
413 void gfs2_statfs_change_in(struct gfs2_statfs_change_host *sc, const void *buf)
414 {
415 	const struct gfs2_statfs_change *str = buf;
416 
417 	sc->sc_total = be64_to_cpu(str->sc_total);
418 	sc->sc_free = be64_to_cpu(str->sc_free);
419 	sc->sc_dinodes = be64_to_cpu(str->sc_dinodes);
420 }
421 
422 static void gfs2_statfs_change_out(const struct gfs2_statfs_change_host *sc, void *buf)
423 {
424 	struct gfs2_statfs_change *str = buf;
425 
426 	str->sc_total = cpu_to_be64(sc->sc_total);
427 	str->sc_free = cpu_to_be64(sc->sc_free);
428 	str->sc_dinodes = cpu_to_be64(sc->sc_dinodes);
429 }
430 
431 int gfs2_statfs_init(struct gfs2_sbd *sdp)
432 {
433 	struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
434 	struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
435 	struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
436 	struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
437 	struct buffer_head *m_bh, *l_bh;
438 	struct gfs2_holder gh;
439 	int error;
440 
441 	error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
442 				   &gh);
443 	if (error)
444 		return error;
445 
446 	error = gfs2_meta_inode_buffer(m_ip, &m_bh);
447 	if (error)
448 		goto out;
449 
450 	if (sdp->sd_args.ar_spectator) {
451 		spin_lock(&sdp->sd_statfs_spin);
452 		gfs2_statfs_change_in(m_sc, m_bh->b_data +
453 				      sizeof(struct gfs2_dinode));
454 		spin_unlock(&sdp->sd_statfs_spin);
455 	} else {
456 		error = gfs2_meta_inode_buffer(l_ip, &l_bh);
457 		if (error)
458 			goto out_m_bh;
459 
460 		spin_lock(&sdp->sd_statfs_spin);
461 		gfs2_statfs_change_in(m_sc, m_bh->b_data +
462 				      sizeof(struct gfs2_dinode));
463 		gfs2_statfs_change_in(l_sc, l_bh->b_data +
464 				      sizeof(struct gfs2_dinode));
465 		spin_unlock(&sdp->sd_statfs_spin);
466 
467 		brelse(l_bh);
468 	}
469 
470 out_m_bh:
471 	brelse(m_bh);
472 out:
473 	gfs2_glock_dq_uninit(&gh);
474 	return 0;
475 }
476 
477 void gfs2_statfs_change(struct gfs2_sbd *sdp, s64 total, s64 free,
478 			s64 dinodes)
479 {
480 	struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
481 	struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
482 	struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
483 	struct buffer_head *l_bh;
484 	s64 x, y;
485 	int need_sync = 0;
486 	int error;
487 
488 	error = gfs2_meta_inode_buffer(l_ip, &l_bh);
489 	if (error)
490 		return;
491 
492 	gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
493 
494 	spin_lock(&sdp->sd_statfs_spin);
495 	l_sc->sc_total += total;
496 	l_sc->sc_free += free;
497 	l_sc->sc_dinodes += dinodes;
498 	gfs2_statfs_change_out(l_sc, l_bh->b_data + sizeof(struct gfs2_dinode));
499 	if (sdp->sd_args.ar_statfs_percent) {
500 		x = 100 * l_sc->sc_free;
501 		y = m_sc->sc_free * sdp->sd_args.ar_statfs_percent;
502 		if (x >= y || x <= -y)
503 			need_sync = 1;
504 	}
505 	spin_unlock(&sdp->sd_statfs_spin);
506 
507 	brelse(l_bh);
508 	if (need_sync)
509 		gfs2_wake_up_statfs(sdp);
510 }
511 
512 void update_statfs(struct gfs2_sbd *sdp, struct buffer_head *m_bh,
513 		   struct buffer_head *l_bh)
514 {
515 	struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
516 	struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
517 	struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
518 	struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
519 
520 	gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
521 
522 	spin_lock(&sdp->sd_statfs_spin);
523 	m_sc->sc_total += l_sc->sc_total;
524 	m_sc->sc_free += l_sc->sc_free;
525 	m_sc->sc_dinodes += l_sc->sc_dinodes;
526 	memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
527 	memset(l_bh->b_data + sizeof(struct gfs2_dinode),
528 	       0, sizeof(struct gfs2_statfs_change));
529 	spin_unlock(&sdp->sd_statfs_spin);
530 
531 	gfs2_trans_add_bh(m_ip->i_gl, m_bh, 1);
532 	gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
533 }
534 
535 int gfs2_statfs_sync(struct super_block *sb, int type)
536 {
537 	struct gfs2_sbd *sdp = sb->s_fs_info;
538 	struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
539 	struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
540 	struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
541 	struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
542 	struct gfs2_holder gh;
543 	struct buffer_head *m_bh, *l_bh;
544 	int error;
545 
546 	error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
547 				   &gh);
548 	if (error)
549 		return error;
550 
551 	error = gfs2_meta_inode_buffer(m_ip, &m_bh);
552 	if (error)
553 		goto out;
554 
555 	spin_lock(&sdp->sd_statfs_spin);
556 	gfs2_statfs_change_in(m_sc, m_bh->b_data +
557 			      sizeof(struct gfs2_dinode));
558 	if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
559 		spin_unlock(&sdp->sd_statfs_spin);
560 		goto out_bh;
561 	}
562 	spin_unlock(&sdp->sd_statfs_spin);
563 
564 	error = gfs2_meta_inode_buffer(l_ip, &l_bh);
565 	if (error)
566 		goto out_bh;
567 
568 	error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
569 	if (error)
570 		goto out_bh2;
571 
572 	update_statfs(sdp, m_bh, l_bh);
573 	sdp->sd_statfs_force_sync = 0;
574 
575 	gfs2_trans_end(sdp);
576 
577 out_bh2:
578 	brelse(l_bh);
579 out_bh:
580 	brelse(m_bh);
581 out:
582 	gfs2_glock_dq_uninit(&gh);
583 	return error;
584 }
585 
586 struct lfcc {
587 	struct list_head list;
588 	struct gfs2_holder gh;
589 };
590 
591 /**
592  * gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
593  *                            journals are clean
594  * @sdp: the file system
595  * @state: the state to put the transaction lock into
596  * @t_gh: the hold on the transaction lock
597  *
598  * Returns: errno
599  */
600 
601 static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp,
602 				    struct gfs2_holder *t_gh)
603 {
604 	struct gfs2_inode *ip;
605 	struct gfs2_jdesc *jd;
606 	struct lfcc *lfcc;
607 	LIST_HEAD(list);
608 	struct gfs2_log_header_host lh;
609 	int error;
610 
611 	list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
612 		lfcc = kmalloc(sizeof(struct lfcc), GFP_KERNEL);
613 		if (!lfcc) {
614 			error = -ENOMEM;
615 			goto out;
616 		}
617 		ip = GFS2_I(jd->jd_inode);
618 		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &lfcc->gh);
619 		if (error) {
620 			kfree(lfcc);
621 			goto out;
622 		}
623 		list_add(&lfcc->list, &list);
624 	}
625 
626 	error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_DEFERRED,
627 				   GL_NOCACHE, t_gh);
628 
629 	list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
630 		error = gfs2_jdesc_check(jd);
631 		if (error)
632 			break;
633 		error = gfs2_find_jhead(jd, &lh);
634 		if (error)
635 			break;
636 		if (!(lh.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
637 			error = -EBUSY;
638 			break;
639 		}
640 	}
641 
642 	if (error)
643 		gfs2_glock_dq_uninit(t_gh);
644 
645 out:
646 	while (!list_empty(&list)) {
647 		lfcc = list_entry(list.next, struct lfcc, list);
648 		list_del(&lfcc->list);
649 		gfs2_glock_dq_uninit(&lfcc->gh);
650 		kfree(lfcc);
651 	}
652 	return error;
653 }
654 
655 /**
656  * gfs2_freeze_fs - freezes the file system
657  * @sdp: the file system
658  *
659  * This function flushes data and meta data for all machines by
660  * aquiring the transaction log exclusively.  All journals are
661  * ensured to be in a clean state as well.
662  *
663  * Returns: errno
664  */
665 
666 int gfs2_freeze_fs(struct gfs2_sbd *sdp)
667 {
668 	int error = 0;
669 
670 	mutex_lock(&sdp->sd_freeze_lock);
671 
672 	if (!sdp->sd_freeze_count++) {
673 		error = gfs2_lock_fs_check_clean(sdp, &sdp->sd_freeze_gh);
674 		if (error)
675 			sdp->sd_freeze_count--;
676 	}
677 
678 	mutex_unlock(&sdp->sd_freeze_lock);
679 
680 	return error;
681 }
682 
683 /**
684  * gfs2_unfreeze_fs - unfreezes the file system
685  * @sdp: the file system
686  *
687  * This function allows the file system to proceed by unlocking
688  * the exclusively held transaction lock.  Other GFS2 nodes are
689  * now free to acquire the lock shared and go on with their lives.
690  *
691  */
692 
693 void gfs2_unfreeze_fs(struct gfs2_sbd *sdp)
694 {
695 	mutex_lock(&sdp->sd_freeze_lock);
696 
697 	if (sdp->sd_freeze_count && !--sdp->sd_freeze_count)
698 		gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
699 
700 	mutex_unlock(&sdp->sd_freeze_lock);
701 }
702 
703 
704 /**
705  * gfs2_write_inode - Make sure the inode is stable on the disk
706  * @inode: The inode
707  * @sync: synchronous write flag
708  *
709  * Returns: errno
710  */
711 
712 static int gfs2_write_inode(struct inode *inode, struct writeback_control *wbc)
713 {
714 	struct gfs2_inode *ip = GFS2_I(inode);
715 	struct gfs2_sbd *sdp = GFS2_SB(inode);
716 	struct gfs2_holder gh;
717 	struct buffer_head *bh;
718 	struct timespec atime;
719 	struct gfs2_dinode *di;
720 	int ret = 0;
721 
722 	/* Check this is a "normal" inode, etc */
723 	if (current->flags & PF_MEMALLOC)
724 		return 0;
725 	ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
726 	if (ret)
727 		goto do_flush;
728 	ret = gfs2_trans_begin(sdp, RES_DINODE, 0);
729 	if (ret)
730 		goto do_unlock;
731 	ret = gfs2_meta_inode_buffer(ip, &bh);
732 	if (ret == 0) {
733 		di = (struct gfs2_dinode *)bh->b_data;
734 		atime.tv_sec = be64_to_cpu(di->di_atime);
735 		atime.tv_nsec = be32_to_cpu(di->di_atime_nsec);
736 		if (timespec_compare(&inode->i_atime, &atime) > 0) {
737 			gfs2_trans_add_bh(ip->i_gl, bh, 1);
738 			gfs2_dinode_out(ip, bh->b_data);
739 		}
740 		brelse(bh);
741 	}
742 	gfs2_trans_end(sdp);
743 do_unlock:
744 	gfs2_glock_dq_uninit(&gh);
745 do_flush:
746 	if (wbc->sync_mode == WB_SYNC_ALL)
747 		gfs2_log_flush(GFS2_SB(inode), ip->i_gl);
748 	return ret;
749 }
750 
751 /**
752  * gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
753  * @sdp: the filesystem
754  *
755  * Returns: errno
756  */
757 
758 static int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
759 {
760 	struct gfs2_holder t_gh;
761 	int error;
762 
763 	flush_workqueue(gfs2_delete_workqueue);
764 	gfs2_quota_sync(sdp->sd_vfs, 0, 1);
765 	gfs2_statfs_sync(sdp->sd_vfs, 0);
766 
767 	error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED, GL_NOCACHE,
768 				   &t_gh);
769 	if (error && !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
770 		return error;
771 
772 	gfs2_meta_syncfs(sdp);
773 	gfs2_log_shutdown(sdp);
774 
775 	clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
776 
777 	if (t_gh.gh_gl)
778 		gfs2_glock_dq_uninit(&t_gh);
779 
780 	gfs2_quota_cleanup(sdp);
781 
782 	return error;
783 }
784 
785 static int gfs2_umount_recovery_wait(void *word)
786 {
787 	schedule();
788 	return 0;
789 }
790 
791 /**
792  * gfs2_put_super - Unmount the filesystem
793  * @sb: The VFS superblock
794  *
795  */
796 
797 static void gfs2_put_super(struct super_block *sb)
798 {
799 	struct gfs2_sbd *sdp = sb->s_fs_info;
800 	int error;
801 	struct gfs2_jdesc *jd;
802 
803 	/*  Unfreeze the filesystem, if we need to  */
804 
805 	mutex_lock(&sdp->sd_freeze_lock);
806 	if (sdp->sd_freeze_count)
807 		gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
808 	mutex_unlock(&sdp->sd_freeze_lock);
809 
810 	/* No more recovery requests */
811 	set_bit(SDF_NORECOVERY, &sdp->sd_flags);
812 	smp_mb();
813 
814 	/* Wait on outstanding recovery */
815 restart:
816 	spin_lock(&sdp->sd_jindex_spin);
817 	list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
818 		if (!test_bit(JDF_RECOVERY, &jd->jd_flags))
819 			continue;
820 		spin_unlock(&sdp->sd_jindex_spin);
821 		wait_on_bit(&jd->jd_flags, JDF_RECOVERY,
822 			    gfs2_umount_recovery_wait, TASK_UNINTERRUPTIBLE);
823 		goto restart;
824 	}
825 	spin_unlock(&sdp->sd_jindex_spin);
826 
827 	kthread_stop(sdp->sd_quotad_process);
828 	kthread_stop(sdp->sd_logd_process);
829 
830 	if (!(sb->s_flags & MS_RDONLY)) {
831 		error = gfs2_make_fs_ro(sdp);
832 		if (error)
833 			gfs2_io_error(sdp);
834 	}
835 	/*  At this point, we're through modifying the disk  */
836 
837 	/*  Release stuff  */
838 
839 	iput(sdp->sd_jindex);
840 	iput(sdp->sd_statfs_inode);
841 	iput(sdp->sd_rindex);
842 	iput(sdp->sd_quota_inode);
843 
844 	gfs2_glock_put(sdp->sd_rename_gl);
845 	gfs2_glock_put(sdp->sd_trans_gl);
846 
847 	if (!sdp->sd_args.ar_spectator) {
848 		gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
849 		gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
850 		gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
851 		gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
852 		iput(sdp->sd_sc_inode);
853 		iput(sdp->sd_qc_inode);
854 	}
855 
856 	gfs2_glock_dq_uninit(&sdp->sd_live_gh);
857 	gfs2_clear_rgrpd(sdp);
858 	gfs2_jindex_free(sdp);
859 	/*  Take apart glock structures and buffer lists  */
860 	gfs2_gl_hash_clear(sdp);
861 	/*  Unmount the locking protocol  */
862 	gfs2_lm_unmount(sdp);
863 
864 	/*  At this point, we're through participating in the lockspace  */
865 	gfs2_sys_fs_del(sdp);
866 }
867 
868 /**
869  * gfs2_sync_fs - sync the filesystem
870  * @sb: the superblock
871  *
872  * Flushes the log to disk.
873  */
874 
875 static int gfs2_sync_fs(struct super_block *sb, int wait)
876 {
877 	if (wait && sb->s_fs_info)
878 		gfs2_log_flush(sb->s_fs_info, NULL);
879 	return 0;
880 }
881 
882 /**
883  * gfs2_freeze - prevent further writes to the filesystem
884  * @sb: the VFS structure for the filesystem
885  *
886  */
887 
888 static int gfs2_freeze(struct super_block *sb)
889 {
890 	struct gfs2_sbd *sdp = sb->s_fs_info;
891 	int error;
892 
893 	if (test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
894 		return -EINVAL;
895 
896 	for (;;) {
897 		error = gfs2_freeze_fs(sdp);
898 		if (!error)
899 			break;
900 
901 		switch (error) {
902 		case -EBUSY:
903 			fs_err(sdp, "waiting for recovery before freeze\n");
904 			break;
905 
906 		default:
907 			fs_err(sdp, "error freezing FS: %d\n", error);
908 			break;
909 		}
910 
911 		fs_err(sdp, "retrying...\n");
912 		msleep(1000);
913 	}
914 	return 0;
915 }
916 
917 /**
918  * gfs2_unfreeze - reallow writes to the filesystem
919  * @sb: the VFS structure for the filesystem
920  *
921  */
922 
923 static int gfs2_unfreeze(struct super_block *sb)
924 {
925 	gfs2_unfreeze_fs(sb->s_fs_info);
926 	return 0;
927 }
928 
929 /**
930  * statfs_fill - fill in the sg for a given RG
931  * @rgd: the RG
932  * @sc: the sc structure
933  *
934  * Returns: 0 on success, -ESTALE if the LVB is invalid
935  */
936 
937 static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
938 			    struct gfs2_statfs_change_host *sc)
939 {
940 	gfs2_rgrp_verify(rgd);
941 	sc->sc_total += rgd->rd_data;
942 	sc->sc_free += rgd->rd_free;
943 	sc->sc_dinodes += rgd->rd_dinodes;
944 	return 0;
945 }
946 
947 /**
948  * gfs2_statfs_slow - Stat a filesystem using asynchronous locking
949  * @sdp: the filesystem
950  * @sc: the sc info that will be returned
951  *
952  * Any error (other than a signal) will cause this routine to fall back
953  * to the synchronous version.
954  *
955  * FIXME: This really shouldn't busy wait like this.
956  *
957  * Returns: errno
958  */
959 
960 static int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
961 {
962 	struct gfs2_holder ri_gh;
963 	struct gfs2_rgrpd *rgd_next;
964 	struct gfs2_holder *gha, *gh;
965 	unsigned int slots = 64;
966 	unsigned int x;
967 	int done;
968 	int error = 0, err;
969 
970 	memset(sc, 0, sizeof(struct gfs2_statfs_change_host));
971 	gha = kcalloc(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
972 	if (!gha)
973 		return -ENOMEM;
974 
975 	error = gfs2_rindex_hold(sdp, &ri_gh);
976 	if (error)
977 		goto out;
978 
979 	rgd_next = gfs2_rgrpd_get_first(sdp);
980 
981 	for (;;) {
982 		done = 1;
983 
984 		for (x = 0; x < slots; x++) {
985 			gh = gha + x;
986 
987 			if (gh->gh_gl && gfs2_glock_poll(gh)) {
988 				err = gfs2_glock_wait(gh);
989 				if (err) {
990 					gfs2_holder_uninit(gh);
991 					error = err;
992 				} else {
993 					if (!error)
994 						error = statfs_slow_fill(
995 							gh->gh_gl->gl_object, sc);
996 					gfs2_glock_dq_uninit(gh);
997 				}
998 			}
999 
1000 			if (gh->gh_gl)
1001 				done = 0;
1002 			else if (rgd_next && !error) {
1003 				error = gfs2_glock_nq_init(rgd_next->rd_gl,
1004 							   LM_ST_SHARED,
1005 							   GL_ASYNC,
1006 							   gh);
1007 				rgd_next = gfs2_rgrpd_get_next(rgd_next);
1008 				done = 0;
1009 			}
1010 
1011 			if (signal_pending(current))
1012 				error = -ERESTARTSYS;
1013 		}
1014 
1015 		if (done)
1016 			break;
1017 
1018 		yield();
1019 	}
1020 
1021 	gfs2_glock_dq_uninit(&ri_gh);
1022 
1023 out:
1024 	kfree(gha);
1025 	return error;
1026 }
1027 
1028 /**
1029  * gfs2_statfs_i - Do a statfs
1030  * @sdp: the filesystem
1031  * @sg: the sg structure
1032  *
1033  * Returns: errno
1034  */
1035 
1036 static int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
1037 {
1038 	struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
1039 	struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
1040 
1041 	spin_lock(&sdp->sd_statfs_spin);
1042 
1043 	*sc = *m_sc;
1044 	sc->sc_total += l_sc->sc_total;
1045 	sc->sc_free += l_sc->sc_free;
1046 	sc->sc_dinodes += l_sc->sc_dinodes;
1047 
1048 	spin_unlock(&sdp->sd_statfs_spin);
1049 
1050 	if (sc->sc_free < 0)
1051 		sc->sc_free = 0;
1052 	if (sc->sc_free > sc->sc_total)
1053 		sc->sc_free = sc->sc_total;
1054 	if (sc->sc_dinodes < 0)
1055 		sc->sc_dinodes = 0;
1056 
1057 	return 0;
1058 }
1059 
1060 /**
1061  * gfs2_statfs - Gather and return stats about the filesystem
1062  * @sb: The superblock
1063  * @statfsbuf: The buffer
1064  *
1065  * Returns: 0 on success or error code
1066  */
1067 
1068 static int gfs2_statfs(struct dentry *dentry, struct kstatfs *buf)
1069 {
1070 	struct super_block *sb = dentry->d_inode->i_sb;
1071 	struct gfs2_sbd *sdp = sb->s_fs_info;
1072 	struct gfs2_statfs_change_host sc;
1073 	int error;
1074 
1075 	if (gfs2_tune_get(sdp, gt_statfs_slow))
1076 		error = gfs2_statfs_slow(sdp, &sc);
1077 	else
1078 		error = gfs2_statfs_i(sdp, &sc);
1079 
1080 	if (error)
1081 		return error;
1082 
1083 	buf->f_type = GFS2_MAGIC;
1084 	buf->f_bsize = sdp->sd_sb.sb_bsize;
1085 	buf->f_blocks = sc.sc_total;
1086 	buf->f_bfree = sc.sc_free;
1087 	buf->f_bavail = sc.sc_free;
1088 	buf->f_files = sc.sc_dinodes + sc.sc_free;
1089 	buf->f_ffree = sc.sc_free;
1090 	buf->f_namelen = GFS2_FNAMESIZE;
1091 
1092 	return 0;
1093 }
1094 
1095 /**
1096  * gfs2_remount_fs - called when the FS is remounted
1097  * @sb:  the filesystem
1098  * @flags:  the remount flags
1099  * @data:  extra data passed in (not used right now)
1100  *
1101  * Returns: errno
1102  */
1103 
1104 static int gfs2_remount_fs(struct super_block *sb, int *flags, char *data)
1105 {
1106 	struct gfs2_sbd *sdp = sb->s_fs_info;
1107 	struct gfs2_args args = sdp->sd_args; /* Default to current settings */
1108 	struct gfs2_tune *gt = &sdp->sd_tune;
1109 	int error;
1110 
1111 	spin_lock(&gt->gt_spin);
1112 	args.ar_commit = gt->gt_logd_secs;
1113 	args.ar_quota_quantum = gt->gt_quota_quantum;
1114 	if (gt->gt_statfs_slow)
1115 		args.ar_statfs_quantum = 0;
1116 	else
1117 		args.ar_statfs_quantum = gt->gt_statfs_quantum;
1118 	spin_unlock(&gt->gt_spin);
1119 	error = gfs2_mount_args(&args, data);
1120 	if (error)
1121 		return error;
1122 
1123 	/* Not allowed to change locking details */
1124 	if (strcmp(args.ar_lockproto, sdp->sd_args.ar_lockproto) ||
1125 	    strcmp(args.ar_locktable, sdp->sd_args.ar_locktable) ||
1126 	    strcmp(args.ar_hostdata, sdp->sd_args.ar_hostdata))
1127 		return -EINVAL;
1128 
1129 	/* Some flags must not be changed */
1130 	if (args_neq(&args, &sdp->sd_args, spectator) ||
1131 	    args_neq(&args, &sdp->sd_args, localflocks) ||
1132 	    args_neq(&args, &sdp->sd_args, meta))
1133 		return -EINVAL;
1134 
1135 	if (sdp->sd_args.ar_spectator)
1136 		*flags |= MS_RDONLY;
1137 
1138 	if ((sb->s_flags ^ *flags) & MS_RDONLY) {
1139 		if (*flags & MS_RDONLY)
1140 			error = gfs2_make_fs_ro(sdp);
1141 		else
1142 			error = gfs2_make_fs_rw(sdp);
1143 		if (error)
1144 			return error;
1145 	}
1146 
1147 	sdp->sd_args = args;
1148 	if (sdp->sd_args.ar_posix_acl)
1149 		sb->s_flags |= MS_POSIXACL;
1150 	else
1151 		sb->s_flags &= ~MS_POSIXACL;
1152 	if (sdp->sd_args.ar_nobarrier)
1153 		set_bit(SDF_NOBARRIERS, &sdp->sd_flags);
1154 	else
1155 		clear_bit(SDF_NOBARRIERS, &sdp->sd_flags);
1156 	spin_lock(&gt->gt_spin);
1157 	gt->gt_logd_secs = args.ar_commit;
1158 	gt->gt_quota_quantum = args.ar_quota_quantum;
1159 	if (args.ar_statfs_quantum) {
1160 		gt->gt_statfs_slow = 0;
1161 		gt->gt_statfs_quantum = args.ar_statfs_quantum;
1162 	}
1163 	else {
1164 		gt->gt_statfs_slow = 1;
1165 		gt->gt_statfs_quantum = 30;
1166 	}
1167 	spin_unlock(&gt->gt_spin);
1168 
1169 	gfs2_online_uevent(sdp);
1170 	return 0;
1171 }
1172 
1173 /**
1174  * gfs2_drop_inode - Drop an inode (test for remote unlink)
1175  * @inode: The inode to drop
1176  *
1177  * If we've received a callback on an iopen lock then its because a
1178  * remote node tried to deallocate the inode but failed due to this node
1179  * still having the inode open. Here we mark the link count zero
1180  * since we know that it must have reached zero if the GLF_DEMOTE flag
1181  * is set on the iopen glock. If we didn't do a disk read since the
1182  * remote node removed the final link then we might otherwise miss
1183  * this event. This check ensures that this node will deallocate the
1184  * inode's blocks, or alternatively pass the baton on to another
1185  * node for later deallocation.
1186  */
1187 
1188 static int gfs2_drop_inode(struct inode *inode)
1189 {
1190 	struct gfs2_inode *ip = GFS2_I(inode);
1191 
1192 	if (inode->i_nlink) {
1193 		struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
1194 		if (gl && test_bit(GLF_DEMOTE, &gl->gl_flags))
1195 			clear_nlink(inode);
1196 	}
1197 	return generic_drop_inode(inode);
1198 }
1199 
1200 static int is_ancestor(const struct dentry *d1, const struct dentry *d2)
1201 {
1202 	do {
1203 		if (d1 == d2)
1204 			return 1;
1205 		d1 = d1->d_parent;
1206 	} while (!IS_ROOT(d1));
1207 	return 0;
1208 }
1209 
1210 /**
1211  * gfs2_show_options - Show mount options for /proc/mounts
1212  * @s: seq_file structure
1213  * @mnt: vfsmount
1214  *
1215  * Returns: 0 on success or error code
1216  */
1217 
1218 static int gfs2_show_options(struct seq_file *s, struct vfsmount *mnt)
1219 {
1220 	struct gfs2_sbd *sdp = mnt->mnt_sb->s_fs_info;
1221 	struct gfs2_args *args = &sdp->sd_args;
1222 	int val;
1223 
1224 	if (is_ancestor(mnt->mnt_root, sdp->sd_master_dir))
1225 		seq_printf(s, ",meta");
1226 	if (args->ar_lockproto[0])
1227 		seq_printf(s, ",lockproto=%s", args->ar_lockproto);
1228 	if (args->ar_locktable[0])
1229 		seq_printf(s, ",locktable=%s", args->ar_locktable);
1230 	if (args->ar_hostdata[0])
1231 		seq_printf(s, ",hostdata=%s", args->ar_hostdata);
1232 	if (args->ar_spectator)
1233 		seq_printf(s, ",spectator");
1234 	if (args->ar_localflocks)
1235 		seq_printf(s, ",localflocks");
1236 	if (args->ar_debug)
1237 		seq_printf(s, ",debug");
1238 	if (args->ar_posix_acl)
1239 		seq_printf(s, ",acl");
1240 	if (args->ar_quota != GFS2_QUOTA_DEFAULT) {
1241 		char *state;
1242 		switch (args->ar_quota) {
1243 		case GFS2_QUOTA_OFF:
1244 			state = "off";
1245 			break;
1246 		case GFS2_QUOTA_ACCOUNT:
1247 			state = "account";
1248 			break;
1249 		case GFS2_QUOTA_ON:
1250 			state = "on";
1251 			break;
1252 		default:
1253 			state = "unknown";
1254 			break;
1255 		}
1256 		seq_printf(s, ",quota=%s", state);
1257 	}
1258 	if (args->ar_suiddir)
1259 		seq_printf(s, ",suiddir");
1260 	if (args->ar_data != GFS2_DATA_DEFAULT) {
1261 		char *state;
1262 		switch (args->ar_data) {
1263 		case GFS2_DATA_WRITEBACK:
1264 			state = "writeback";
1265 			break;
1266 		case GFS2_DATA_ORDERED:
1267 			state = "ordered";
1268 			break;
1269 		default:
1270 			state = "unknown";
1271 			break;
1272 		}
1273 		seq_printf(s, ",data=%s", state);
1274 	}
1275 	if (args->ar_discard)
1276 		seq_printf(s, ",discard");
1277 	val = sdp->sd_tune.gt_logd_secs;
1278 	if (val != 30)
1279 		seq_printf(s, ",commit=%d", val);
1280 	val = sdp->sd_tune.gt_statfs_quantum;
1281 	if (val != 30)
1282 		seq_printf(s, ",statfs_quantum=%d", val);
1283 	val = sdp->sd_tune.gt_quota_quantum;
1284 	if (val != 60)
1285 		seq_printf(s, ",quota_quantum=%d", val);
1286 	if (args->ar_statfs_percent)
1287 		seq_printf(s, ",statfs_percent=%d", args->ar_statfs_percent);
1288 	if (args->ar_errors != GFS2_ERRORS_DEFAULT) {
1289 		const char *state;
1290 
1291 		switch (args->ar_errors) {
1292 		case GFS2_ERRORS_WITHDRAW:
1293 			state = "withdraw";
1294 			break;
1295 		case GFS2_ERRORS_PANIC:
1296 			state = "panic";
1297 			break;
1298 		default:
1299 			state = "unknown";
1300 			break;
1301 		}
1302 		seq_printf(s, ",errors=%s", state);
1303 	}
1304 	if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags))
1305 		seq_printf(s, ",nobarrier");
1306 	if (test_bit(SDF_DEMOTE, &sdp->sd_flags))
1307 		seq_printf(s, ",demote_interface_used");
1308 	return 0;
1309 }
1310 
1311 /*
1312  * We have to (at the moment) hold the inodes main lock to cover
1313  * the gap between unlocking the shared lock on the iopen lock and
1314  * taking the exclusive lock. I'd rather do a shared -> exclusive
1315  * conversion on the iopen lock, but we can change that later. This
1316  * is safe, just less efficient.
1317  */
1318 
1319 static void gfs2_evict_inode(struct inode *inode)
1320 {
1321 	struct gfs2_sbd *sdp = inode->i_sb->s_fs_info;
1322 	struct gfs2_inode *ip = GFS2_I(inode);
1323 	struct gfs2_holder gh;
1324 	int error;
1325 
1326 	if (inode->i_nlink)
1327 		goto out;
1328 
1329 	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
1330 	if (unlikely(error)) {
1331 		gfs2_glock_dq_uninit(&ip->i_iopen_gh);
1332 		goto out;
1333 	}
1334 
1335 	error = gfs2_check_blk_type(sdp, ip->i_no_addr, GFS2_BLKST_UNLINKED);
1336 	if (error)
1337 		goto out_truncate;
1338 
1339 	ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1340 	gfs2_glock_dq_wait(&ip->i_iopen_gh);
1341 	gfs2_holder_reinit(LM_ST_EXCLUSIVE, LM_FLAG_TRY_1CB | GL_NOCACHE, &ip->i_iopen_gh);
1342 	error = gfs2_glock_nq(&ip->i_iopen_gh);
1343 	if (error)
1344 		goto out_truncate;
1345 
1346 	if (S_ISDIR(inode->i_mode) &&
1347 	    (ip->i_diskflags & GFS2_DIF_EXHASH)) {
1348 		error = gfs2_dir_exhash_dealloc(ip);
1349 		if (error)
1350 			goto out_unlock;
1351 	}
1352 
1353 	if (ip->i_eattr) {
1354 		error = gfs2_ea_dealloc(ip);
1355 		if (error)
1356 			goto out_unlock;
1357 	}
1358 
1359 	if (!gfs2_is_stuffed(ip)) {
1360 		error = gfs2_file_dealloc(ip);
1361 		if (error)
1362 			goto out_unlock;
1363 	}
1364 
1365 	error = gfs2_dinode_dealloc(ip);
1366 	if (error)
1367 		goto out_unlock;
1368 
1369 out_truncate:
1370 	error = gfs2_trans_begin(sdp, 0, sdp->sd_jdesc->jd_blocks);
1371 	if (error)
1372 		goto out_unlock;
1373 	/* Needs to be done before glock release & also in a transaction */
1374 	truncate_inode_pages(&inode->i_data, 0);
1375 	gfs2_trans_end(sdp);
1376 
1377 out_unlock:
1378 	if (test_bit(HIF_HOLDER, &ip->i_iopen_gh.gh_iflags))
1379 		gfs2_glock_dq(&ip->i_iopen_gh);
1380 	gfs2_holder_uninit(&ip->i_iopen_gh);
1381 	gfs2_glock_dq_uninit(&gh);
1382 	if (error && error != GLR_TRYFAILED && error != -EROFS)
1383 		fs_warn(sdp, "gfs2_evict_inode: %d\n", error);
1384 out:
1385 	truncate_inode_pages(&inode->i_data, 0);
1386 	end_writeback(inode);
1387 
1388 	ip->i_gl->gl_object = NULL;
1389 	gfs2_glock_put(ip->i_gl);
1390 	ip->i_gl = NULL;
1391 	if (ip->i_iopen_gh.gh_gl) {
1392 		ip->i_iopen_gh.gh_gl->gl_object = NULL;
1393 		gfs2_glock_dq_uninit(&ip->i_iopen_gh);
1394 	}
1395 }
1396 
1397 static struct inode *gfs2_alloc_inode(struct super_block *sb)
1398 {
1399 	struct gfs2_inode *ip;
1400 
1401 	ip = kmem_cache_alloc(gfs2_inode_cachep, GFP_KERNEL);
1402 	if (ip) {
1403 		ip->i_flags = 0;
1404 		ip->i_gl = NULL;
1405 	}
1406 	return &ip->i_inode;
1407 }
1408 
1409 static void gfs2_i_callback(struct rcu_head *head)
1410 {
1411 	struct inode *inode = container_of(head, struct inode, i_rcu);
1412 	INIT_LIST_HEAD(&inode->i_dentry);
1413 	kmem_cache_free(gfs2_inode_cachep, inode);
1414 }
1415 
1416 static void gfs2_destroy_inode(struct inode *inode)
1417 {
1418 	call_rcu(&inode->i_rcu, gfs2_i_callback);
1419 }
1420 
1421 const struct super_operations gfs2_super_ops = {
1422 	.alloc_inode		= gfs2_alloc_inode,
1423 	.destroy_inode		= gfs2_destroy_inode,
1424 	.write_inode		= gfs2_write_inode,
1425 	.evict_inode		= gfs2_evict_inode,
1426 	.put_super		= gfs2_put_super,
1427 	.sync_fs		= gfs2_sync_fs,
1428 	.freeze_fs 		= gfs2_freeze,
1429 	.unfreeze_fs		= gfs2_unfreeze,
1430 	.statfs			= gfs2_statfs,
1431 	.remount_fs		= gfs2_remount_fs,
1432 	.drop_inode		= gfs2_drop_inode,
1433 	.show_options		= gfs2_show_options,
1434 };
1435 
1436