xref: /openbmc/linux/fs/gfs2/inode.c (revision f55ab26a)
1 /*
2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
3  * Copyright (C) 2004-2005 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 v.2.
8  */
9 
10 #include <linux/sched.h>
11 #include <linux/slab.h>
12 #include <linux/spinlock.h>
13 #include <linux/completion.h>
14 #include <linux/buffer_head.h>
15 #include <linux/posix_acl.h>
16 #include <linux/sort.h>
17 #include <asm/semaphore.h>
18 
19 #include "gfs2.h"
20 #include "acl.h"
21 #include "bmap.h"
22 #include "dir.h"
23 #include "eattr.h"
24 #include "glock.h"
25 #include "glops.h"
26 #include "inode.h"
27 #include "log.h"
28 #include "meta_io.h"
29 #include "ops_address.h"
30 #include "ops_file.h"
31 #include "ops_inode.h"
32 #include "quota.h"
33 #include "rgrp.h"
34 #include "trans.h"
35 #include "unlinked.h"
36 
37 /**
38  * inode_attr_in - Copy attributes from the dinode into the VFS inode
39  * @ip: The GFS2 inode (with embedded disk inode data)
40  * @inode:  The Linux VFS inode
41  *
42  */
43 
44 static void inode_attr_in(struct gfs2_inode *ip, struct inode *inode)
45 {
46 	inode->i_ino = ip->i_num.no_formal_ino;
47 
48 	switch (ip->i_di.di_mode & S_IFMT) {
49 	case S_IFBLK:
50 	case S_IFCHR:
51 		inode->i_rdev = MKDEV(ip->i_di.di_major, ip->i_di.di_minor);
52 		break;
53 	default:
54 		inode->i_rdev = 0;
55 		break;
56 	};
57 
58 	inode->i_mode = ip->i_di.di_mode;
59 	inode->i_nlink = ip->i_di.di_nlink;
60 	inode->i_uid = ip->i_di.di_uid;
61 	inode->i_gid = ip->i_di.di_gid;
62 	i_size_write(inode, ip->i_di.di_size);
63 	inode->i_atime.tv_sec = ip->i_di.di_atime;
64 	inode->i_mtime.tv_sec = ip->i_di.di_mtime;
65 	inode->i_ctime.tv_sec = ip->i_di.di_ctime;
66 	inode->i_atime.tv_nsec = 0;
67 	inode->i_mtime.tv_nsec = 0;
68 	inode->i_ctime.tv_nsec = 0;
69 	inode->i_blksize = PAGE_SIZE;
70 	inode->i_blocks = ip->i_di.di_blocks <<
71 		(ip->i_sbd->sd_sb.sb_bsize_shift - GFS2_BASIC_BLOCK_SHIFT);
72 
73 	if (ip->i_di.di_flags & GFS2_DIF_IMMUTABLE)
74 		inode->i_flags |= S_IMMUTABLE;
75 	else
76 		inode->i_flags &= ~S_IMMUTABLE;
77 
78 	if (ip->i_di.di_flags & GFS2_DIF_APPENDONLY)
79 		inode->i_flags |= S_APPEND;
80 	else
81 		inode->i_flags &= ~S_APPEND;
82 }
83 
84 /**
85  * gfs2_inode_attr_in - Copy attributes from the dinode into the VFS inode
86  * @ip: The GFS2 inode (with embedded disk inode data)
87  *
88  */
89 
90 void gfs2_inode_attr_in(struct gfs2_inode *ip)
91 {
92 	struct inode *inode;
93 
94 	inode = gfs2_ip2v_lookup(ip);
95 	if (inode) {
96 		inode_attr_in(ip, inode);
97 		iput(inode);
98 	}
99 }
100 
101 /**
102  * gfs2_inode_attr_out - Copy attributes from VFS inode into the dinode
103  * @ip: The GFS2 inode
104  *
105  * Only copy out the attributes that we want the VFS layer
106  * to be able to modify.
107  */
108 
109 void gfs2_inode_attr_out(struct gfs2_inode *ip)
110 {
111 	struct inode *inode = ip->i_vnode;
112 
113 	gfs2_assert_withdraw(ip->i_sbd,
114 		(ip->i_di.di_mode & S_IFMT) == (inode->i_mode & S_IFMT));
115 	ip->i_di.di_mode = inode->i_mode;
116 	ip->i_di.di_uid = inode->i_uid;
117 	ip->i_di.di_gid = inode->i_gid;
118 	ip->i_di.di_atime = inode->i_atime.tv_sec;
119 	ip->i_di.di_mtime = inode->i_mtime.tv_sec;
120 	ip->i_di.di_ctime = inode->i_ctime.tv_sec;
121 }
122 
123 /**
124  * gfs2_ip2v_lookup - Get the struct inode for a struct gfs2_inode
125  * @ip: the struct gfs2_inode to get the struct inode for
126  *
127  * Returns: A VFS inode, or NULL if none
128  */
129 
130 struct inode *gfs2_ip2v_lookup(struct gfs2_inode *ip)
131 {
132 	struct inode *inode = NULL;
133 
134 	gfs2_assert_warn(ip->i_sbd, test_bit(GIF_MIN_INIT, &ip->i_flags));
135 
136 	spin_lock(&ip->i_spin);
137 	if (ip->i_vnode)
138 		inode = igrab(ip->i_vnode);
139 	spin_unlock(&ip->i_spin);
140 
141 	return inode;
142 }
143 
144 /**
145  * gfs2_ip2v - Get/Create a struct inode for a struct gfs2_inode
146  * @ip: the struct gfs2_inode to get the struct inode for
147  *
148  * Returns: A VFS inode, or NULL if no mem
149  */
150 
151 struct inode *gfs2_ip2v(struct gfs2_inode *ip)
152 {
153 	struct inode *inode, *tmp;
154 
155 	inode = gfs2_ip2v_lookup(ip);
156 	if (inode)
157 		return inode;
158 
159 	tmp = new_inode(ip->i_sbd->sd_vfs);
160 	if (!tmp)
161 		return NULL;
162 
163 	inode_attr_in(ip, tmp);
164 
165 	if (S_ISREG(ip->i_di.di_mode)) {
166 		tmp->i_op = &gfs2_file_iops;
167 		tmp->i_fop = &gfs2_file_fops;
168 		tmp->i_mapping->a_ops = &gfs2_file_aops;
169 	} else if (S_ISDIR(ip->i_di.di_mode)) {
170 		tmp->i_op = &gfs2_dir_iops;
171 		tmp->i_fop = &gfs2_dir_fops;
172 	} else if (S_ISLNK(ip->i_di.di_mode)) {
173 		tmp->i_op = &gfs2_symlink_iops;
174 	} else {
175 		tmp->i_op = &gfs2_dev_iops;
176 		init_special_inode(tmp, tmp->i_mode, tmp->i_rdev);
177 	}
178 
179 	set_v2ip(tmp, NULL);
180 
181 	for (;;) {
182 		spin_lock(&ip->i_spin);
183 		if (!ip->i_vnode)
184 			break;
185 		inode = igrab(ip->i_vnode);
186 		spin_unlock(&ip->i_spin);
187 
188 		if (inode) {
189 			iput(tmp);
190 			return inode;
191 		}
192 		yield();
193 	}
194 
195 	inode = tmp;
196 
197 	gfs2_inode_hold(ip);
198 	ip->i_vnode = inode;
199 	set_v2ip(inode, ip);
200 
201 	spin_unlock(&ip->i_spin);
202 
203 	insert_inode_hash(inode);
204 
205 	return inode;
206 }
207 
208 static int iget_test(struct inode *inode, void *opaque)
209 {
210 	struct gfs2_inode *ip = get_v2ip(inode);
211 	struct gfs2_inum *inum = (struct gfs2_inum *)opaque;
212 
213 	if (ip && ip->i_num.no_addr == inum->no_addr)
214 		return 1;
215 
216 	return 0;
217 }
218 
219 struct inode *gfs2_iget(struct super_block *sb, struct gfs2_inum *inum)
220 {
221 	return ilookup5(sb, (unsigned long)inum->no_formal_ino,
222 			iget_test, inum);
223 }
224 
225 void gfs2_inode_min_init(struct gfs2_inode *ip, unsigned int type)
226 {
227 	spin_lock(&ip->i_spin);
228 	if (!test_and_set_bit(GIF_MIN_INIT, &ip->i_flags)) {
229 		ip->i_di.di_nlink = 1;
230 		ip->i_di.di_mode = DT2IF(type);
231 	}
232 	spin_unlock(&ip->i_spin);
233 }
234 
235 /**
236  * gfs2_inode_refresh - Refresh the incore copy of the dinode
237  * @ip: The GFS2 inode
238  *
239  * Returns: errno
240  */
241 
242 int gfs2_inode_refresh(struct gfs2_inode *ip)
243 {
244 	struct buffer_head *dibh;
245 	int error;
246 
247 	error = gfs2_meta_inode_buffer(ip, &dibh);
248 	if (error)
249 		return error;
250 
251 	if (gfs2_metatype_check(ip->i_sbd, dibh, GFS2_METATYPE_DI)) {
252 		brelse(dibh);
253 		return -EIO;
254 	}
255 
256 	spin_lock(&ip->i_spin);
257 	gfs2_dinode_in(&ip->i_di, dibh->b_data);
258 	set_bit(GIF_MIN_INIT, &ip->i_flags);
259 	spin_unlock(&ip->i_spin);
260 
261 	brelse(dibh);
262 
263 	if (ip->i_num.no_addr != ip->i_di.di_num.no_addr) {
264 		if (gfs2_consist_inode(ip))
265 			gfs2_dinode_print(&ip->i_di);
266 		return -EIO;
267 	}
268 	if (ip->i_num.no_formal_ino != ip->i_di.di_num.no_formal_ino)
269 		return -ESTALE;
270 
271 	ip->i_vn = ip->i_gl->gl_vn;
272 
273 	return 0;
274 }
275 
276 /**
277  * inode_create - create a struct gfs2_inode
278  * @i_gl: The glock covering the inode
279  * @inum: The inode number
280  * @io_gl: the iopen glock to acquire/hold (using holder in new gfs2_inode)
281  * @io_state: the state the iopen glock should be acquired in
282  * @ipp: pointer to put the returned inode in
283  *
284  * Returns: errno
285  */
286 
287 static int inode_create(struct gfs2_glock *i_gl, struct gfs2_inum *inum,
288 			struct gfs2_glock *io_gl, unsigned int io_state,
289 			struct gfs2_inode **ipp)
290 {
291 	struct gfs2_sbd *sdp = i_gl->gl_sbd;
292 	struct gfs2_inode *ip;
293 	int error = 0;
294 
295 	ip = kmem_cache_alloc(gfs2_inode_cachep, GFP_KERNEL);
296 	if (!ip)
297 		return -ENOMEM;
298 	memset(ip, 0, sizeof(struct gfs2_inode));
299 
300 	ip->i_num = *inum;
301 
302 	atomic_set(&ip->i_count, 1);
303 
304 	ip->i_vn = i_gl->gl_vn - 1;
305 
306 	ip->i_gl = i_gl;
307 	ip->i_sbd = sdp;
308 
309 	spin_lock_init(&ip->i_spin);
310 	init_rwsem(&ip->i_rw_mutex);
311 
312 	ip->i_greedy = gfs2_tune_get(sdp, gt_greedy_default);
313 
314 	error = gfs2_glock_nq_init(io_gl,
315 				   io_state, GL_LOCAL_EXCL | GL_EXACT,
316 				   &ip->i_iopen_gh);
317 	if (error)
318 		goto fail;
319 	ip->i_iopen_gh.gh_owner = NULL;
320 
321 	spin_lock(&io_gl->gl_spin);
322 	gfs2_glock_hold(i_gl);
323 	set_gl2gl(io_gl, i_gl);
324 	spin_unlock(&io_gl->gl_spin);
325 
326 	gfs2_glock_hold(i_gl);
327 	set_gl2ip(i_gl, ip);
328 
329 	atomic_inc(&sdp->sd_inode_count);
330 
331 	*ipp = ip;
332 
333 	return 0;
334 
335  fail:
336 	gfs2_meta_cache_flush(ip);
337 	kmem_cache_free(gfs2_inode_cachep, ip);
338 	*ipp = NULL;
339 
340 	return error;
341 }
342 
343 /**
344  * gfs2_inode_get - Create or get a reference on an inode
345  * @i_gl: The glock covering the inode
346  * @inum: The inode number
347  * @create:
348  * @ipp: pointer to put the returned inode in
349  *
350  * Returns: errno
351  */
352 
353 int gfs2_inode_get(struct gfs2_glock *i_gl, struct gfs2_inum *inum, int create,
354 		   struct gfs2_inode **ipp)
355 {
356 	struct gfs2_sbd *sdp = i_gl->gl_sbd;
357 	struct gfs2_glock *io_gl;
358 	int error = 0;
359 
360 	gfs2_glmutex_lock(i_gl);
361 
362 	*ipp = get_gl2ip(i_gl);
363 	if (*ipp) {
364 		error = -ESTALE;
365 		if ((*ipp)->i_num.no_formal_ino != inum->no_formal_ino)
366 			goto out;
367 		atomic_inc(&(*ipp)->i_count);
368 		error = 0;
369 		goto out;
370 	}
371 
372 	if (!create)
373 		goto out;
374 
375 	error = gfs2_glock_get(sdp, inum->no_addr, &gfs2_iopen_glops,
376 			       CREATE, &io_gl);
377 	if (!error) {
378 		error = inode_create(i_gl, inum, io_gl, LM_ST_SHARED, ipp);
379 		gfs2_glock_put(io_gl);
380 	}
381 
382  out:
383 	gfs2_glmutex_unlock(i_gl);
384 
385 	return error;
386 }
387 
388 void gfs2_inode_hold(struct gfs2_inode *ip)
389 {
390 	gfs2_assert(ip->i_sbd, atomic_read(&ip->i_count) > 0);
391 	atomic_inc(&ip->i_count);
392 }
393 
394 void gfs2_inode_put(struct gfs2_inode *ip)
395 {
396 	gfs2_assert(ip->i_sbd, atomic_read(&ip->i_count) > 0);
397 	atomic_dec(&ip->i_count);
398 }
399 
400 void gfs2_inode_destroy(struct gfs2_inode *ip)
401 {
402 	struct gfs2_sbd *sdp = ip->i_sbd;
403 	struct gfs2_glock *io_gl = ip->i_iopen_gh.gh_gl;
404 	struct gfs2_glock *i_gl = ip->i_gl;
405 
406 	gfs2_assert_warn(sdp, !atomic_read(&ip->i_count));
407 	gfs2_assert(sdp, get_gl2gl(io_gl) == i_gl);
408 
409 	spin_lock(&io_gl->gl_spin);
410 	set_gl2gl(io_gl, NULL);
411 	gfs2_glock_put(i_gl);
412 	spin_unlock(&io_gl->gl_spin);
413 
414 	gfs2_glock_dq_uninit(&ip->i_iopen_gh);
415 
416 	gfs2_meta_cache_flush(ip);
417 	kmem_cache_free(gfs2_inode_cachep, ip);
418 
419 	set_gl2ip(i_gl, NULL);
420 	gfs2_glock_put(i_gl);
421 
422 	atomic_dec(&sdp->sd_inode_count);
423 }
424 
425 static int dinode_dealloc(struct gfs2_inode *ip, struct gfs2_unlinked *ul)
426 {
427 	struct gfs2_sbd *sdp = ip->i_sbd;
428 	struct gfs2_alloc *al;
429 	struct gfs2_rgrpd *rgd;
430 	int error;
431 
432 	if (ip->i_di.di_blocks != 1) {
433 		if (gfs2_consist_inode(ip))
434 			gfs2_dinode_print(&ip->i_di);
435 		return -EIO;
436 	}
437 
438 	al = gfs2_alloc_get(ip);
439 
440 	error = gfs2_quota_hold(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
441 	if (error)
442 		goto out;
443 
444 	error = gfs2_rindex_hold(sdp, &al->al_ri_gh);
445 	if (error)
446 		goto out_qs;
447 
448 	rgd = gfs2_blk2rgrpd(sdp, ip->i_num.no_addr);
449 	if (!rgd) {
450 		gfs2_consist_inode(ip);
451 		error = -EIO;
452 		goto out_rindex_relse;
453 	}
454 
455 	error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0,
456 				   &al->al_rgd_gh);
457 	if (error)
458 		goto out_rindex_relse;
459 
460 	error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_UNLINKED +
461 				 RES_STATFS + RES_QUOTA, 1);
462 	if (error)
463 		goto out_rg_gunlock;
464 
465 	gfs2_trans_add_gl(ip->i_gl);
466 
467 	gfs2_free_di(rgd, ip);
468 
469 	error = gfs2_unlinked_ondisk_rm(sdp, ul);
470 
471 	gfs2_trans_end(sdp);
472 	clear_bit(GLF_STICKY, &ip->i_gl->gl_flags);
473 
474  out_rg_gunlock:
475 	gfs2_glock_dq_uninit(&al->al_rgd_gh);
476 
477  out_rindex_relse:
478 	gfs2_glock_dq_uninit(&al->al_ri_gh);
479 
480  out_qs:
481 	gfs2_quota_unhold(ip);
482 
483  out:
484 	gfs2_alloc_put(ip);
485 
486 	return error;
487 }
488 
489 /**
490  * inode_dealloc - Deallocate all on-disk blocks for an inode (dinode)
491  * @sdp: the filesystem
492  * @inum: the inode number to deallocate
493  * @io_gh: a holder for the iopen glock for this inode
494  *
495  * Returns: errno
496  */
497 
498 static int inode_dealloc(struct gfs2_sbd *sdp, struct gfs2_unlinked *ul,
499 			 struct gfs2_holder *io_gh)
500 {
501 	struct gfs2_inode *ip;
502 	struct gfs2_holder i_gh;
503 	int error;
504 
505 	error = gfs2_glock_nq_num(sdp,
506 				  ul->ul_ut.ut_inum.no_addr, &gfs2_inode_glops,
507 				  LM_ST_EXCLUSIVE, 0, &i_gh);
508 	if (error)
509 		return error;
510 
511 	/* We reacquire the iopen lock here to avoid a race with the NFS server
512 	   calling gfs2_read_inode() with the inode number of a inode we're in
513 	   the process of deallocating.  And we can't keep our hold on the lock
514 	   from inode_dealloc_init() for deadlock reasons. */
515 
516 	gfs2_holder_reinit(LM_ST_EXCLUSIVE, LM_FLAG_TRY, io_gh);
517 	error = gfs2_glock_nq(io_gh);
518 	switch (error) {
519 	case 0:
520 		break;
521 	case GLR_TRYFAILED:
522 		error = 1;
523 	default:
524 		goto out;
525 	}
526 
527 	gfs2_assert_warn(sdp, !get_gl2ip(i_gh.gh_gl));
528 	error = inode_create(i_gh.gh_gl, &ul->ul_ut.ut_inum, io_gh->gh_gl,
529 			     LM_ST_EXCLUSIVE, &ip);
530 
531 	gfs2_glock_dq(io_gh);
532 
533 	if (error)
534 		goto out;
535 
536 	error = gfs2_inode_refresh(ip);
537 	if (error)
538 		goto out_iput;
539 
540 	if (ip->i_di.di_nlink) {
541 		if (gfs2_consist_inode(ip))
542 			gfs2_dinode_print(&ip->i_di);
543 		error = -EIO;
544 		goto out_iput;
545 	}
546 
547 	if (S_ISDIR(ip->i_di.di_mode) &&
548 	    (ip->i_di.di_flags & GFS2_DIF_EXHASH)) {
549 		error = gfs2_dir_exhash_dealloc(ip);
550 		if (error)
551 			goto out_iput;
552 	}
553 
554 	if (ip->i_di.di_eattr) {
555 		error = gfs2_ea_dealloc(ip);
556 		if (error)
557 			goto out_iput;
558 	}
559 
560 	if (!gfs2_is_stuffed(ip)) {
561 		error = gfs2_file_dealloc(ip);
562 		if (error)
563 			goto out_iput;
564 	}
565 
566 	error = dinode_dealloc(ip, ul);
567 	if (error)
568 		goto out_iput;
569 
570  out_iput:
571 	gfs2_glmutex_lock(i_gh.gh_gl);
572 	gfs2_inode_put(ip);
573 	gfs2_inode_destroy(ip);
574 	gfs2_glmutex_unlock(i_gh.gh_gl);
575 
576  out:
577 	gfs2_glock_dq_uninit(&i_gh);
578 
579 	return error;
580 }
581 
582 /**
583  * try_inode_dealloc - Try to deallocate an inode and all its blocks
584  * @sdp: the filesystem
585  *
586  * Returns: 0 on success, -errno on error, 1 on busy (inode open)
587  */
588 
589 static int try_inode_dealloc(struct gfs2_sbd *sdp, struct gfs2_unlinked *ul)
590 {
591 	struct gfs2_holder io_gh;
592 	int error = 0;
593 
594 	gfs2_try_toss_inode(sdp, &ul->ul_ut.ut_inum);
595 
596 	error = gfs2_glock_nq_num(sdp,
597 				  ul->ul_ut.ut_inum.no_addr, &gfs2_iopen_glops,
598 				  LM_ST_EXCLUSIVE, LM_FLAG_TRY_1CB, &io_gh);
599 	switch (error) {
600 	case 0:
601 		break;
602 	case GLR_TRYFAILED:
603 		return 1;
604 	default:
605 		return error;
606 	}
607 
608 	gfs2_glock_dq(&io_gh);
609 	error = inode_dealloc(sdp, ul, &io_gh);
610 	gfs2_holder_uninit(&io_gh);
611 
612 	return error;
613 }
614 
615 static int inode_dealloc_uninit(struct gfs2_sbd *sdp, struct gfs2_unlinked *ul)
616 {
617 	struct gfs2_rgrpd *rgd;
618 	struct gfs2_holder ri_gh, rgd_gh;
619 	int error;
620 
621 	error = gfs2_rindex_hold(sdp, &ri_gh);
622 	if (error)
623 		return error;
624 
625 	rgd = gfs2_blk2rgrpd(sdp, ul->ul_ut.ut_inum.no_addr);
626 	if (!rgd) {
627 		gfs2_consist(sdp);
628 		error = -EIO;
629 		goto out;
630 	}
631 
632 	error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, &rgd_gh);
633 	if (error)
634 		goto out;
635 
636 	error = gfs2_trans_begin(sdp,
637 				 RES_RG_BIT + RES_UNLINKED + RES_STATFS,
638 				 0);
639 	if (error)
640 		goto out_gunlock;
641 
642 	gfs2_free_uninit_di(rgd, ul->ul_ut.ut_inum.no_addr);
643 	gfs2_unlinked_ondisk_rm(sdp, ul);
644 
645 	gfs2_trans_end(sdp);
646 
647  out_gunlock:
648 	gfs2_glock_dq_uninit(&rgd_gh);
649  out:
650 	gfs2_glock_dq_uninit(&ri_gh);
651 
652 	return error;
653 }
654 
655 int gfs2_inode_dealloc(struct gfs2_sbd *sdp, struct gfs2_unlinked *ul)
656 {
657 	if (ul->ul_ut.ut_flags & GFS2_UTF_UNINIT)
658 		return inode_dealloc_uninit(sdp, ul);
659 	else
660 		return try_inode_dealloc(sdp, ul);
661 }
662 
663 /**
664  * gfs2_change_nlink - Change nlink count on inode
665  * @ip: The GFS2 inode
666  * @diff: The change in the nlink count required
667  *
668  * Returns: errno
669  */
670 
671 int gfs2_change_nlink(struct gfs2_inode *ip, int diff)
672 {
673 	struct buffer_head *dibh;
674 	uint32_t nlink;
675 	int error;
676 
677 	nlink = ip->i_di.di_nlink + diff;
678 
679 	/* If we are reducing the nlink count, but the new value ends up being
680 	   bigger than the old one, we must have underflowed. */
681 	if (diff < 0 && nlink > ip->i_di.di_nlink) {
682 		if (gfs2_consist_inode(ip))
683 			gfs2_dinode_print(&ip->i_di);
684 		return -EIO;
685 	}
686 
687 	error = gfs2_meta_inode_buffer(ip, &dibh);
688 	if (error)
689 		return error;
690 
691 	ip->i_di.di_nlink = nlink;
692 	ip->i_di.di_ctime = get_seconds();
693 
694 	gfs2_trans_add_bh(ip->i_gl, dibh, 1);
695 	gfs2_dinode_out(&ip->i_di, dibh->b_data);
696 	brelse(dibh);
697 
698 	return 0;
699 }
700 
701 /**
702  * gfs2_lookupi - Look up a filename in a directory and return its inode
703  * @d_gh: An initialized holder for the directory glock
704  * @name: The name of the inode to look for
705  * @is_root: If 1, ignore the caller's permissions
706  * @i_gh: An uninitialized holder for the new inode glock
707  *
708  * There will always be a vnode (Linux VFS inode) for the d_gh inode unless
709  * @is_root is true.
710  *
711  * Returns: errno
712  */
713 
714 int gfs2_lookupi(struct inode *dir, struct qstr *name, int is_root,
715 		 struct inode **inodep)
716 {
717 	struct gfs2_inode *ipp;
718 	struct gfs2_inode *dip = get_v2ip(dir);
719 	struct gfs2_sbd *sdp = dip->i_sbd;
720 	struct gfs2_holder d_gh;
721 	struct gfs2_inum inum;
722 	unsigned int type;
723 	struct gfs2_glock *gl;
724 	int error = 0;
725 
726 	*inodep = NULL;
727 
728 	if (!name->len || name->len > GFS2_FNAMESIZE)
729 		return -ENAMETOOLONG;
730 
731 	if (gfs2_filecmp(name, ".", 1) ||
732 	    (gfs2_filecmp(name, "..", 2) && dir == sdp->sd_root_dir)) {
733 		gfs2_inode_hold(dip);
734 		ipp = dip;
735 		goto done;
736 	}
737 
738 	error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh);
739 	if (error)
740 		return error;
741 
742 	if (!is_root) {
743 		error = gfs2_repermission(dip->i_vnode, MAY_EXEC, NULL);
744 		if (error)
745 			goto out;
746 	}
747 
748 	error = gfs2_dir_search(dip, name, &inum, &type);
749 	if (error)
750 		goto out;
751 
752 	error = gfs2_glock_get(sdp, inum.no_addr, &gfs2_inode_glops,
753 			       CREATE, &gl);
754 	if (error)
755 		goto out;
756 
757 	error = gfs2_inode_get(gl, &inum, CREATE, &ipp);
758 	if (!error)
759 		gfs2_inode_min_init(ipp, type);
760 
761 	gfs2_glock_put(gl);
762 
763 out:
764 	gfs2_glock_dq_uninit(&d_gh);
765 done:
766 	if (error == 0) {
767 		*inodep = gfs2_ip2v(ipp);
768 		if (!*inodep)
769 			error = -ENOMEM;
770 		gfs2_inode_put(ipp);
771 	}
772 	return error;
773 }
774 
775 static int pick_formal_ino_1(struct gfs2_sbd *sdp, uint64_t *formal_ino)
776 {
777 	struct gfs2_inode *ip = get_v2ip(sdp->sd_ir_inode);
778 	struct buffer_head *bh;
779 	struct gfs2_inum_range ir;
780 	int error;
781 
782 	error = gfs2_trans_begin(sdp, RES_DINODE, 0);
783 	if (error)
784 		return error;
785 	mutex_lock(&sdp->sd_inum_mutex);
786 
787 	error = gfs2_meta_inode_buffer(ip, &bh);
788 	if (error) {
789 		mutex_unlock(&sdp->sd_inum_mutex);
790 		gfs2_trans_end(sdp);
791 		return error;
792 	}
793 
794 	gfs2_inum_range_in(&ir, bh->b_data + sizeof(struct gfs2_dinode));
795 
796 	if (ir.ir_length) {
797 		*formal_ino = ir.ir_start++;
798 		ir.ir_length--;
799 		gfs2_trans_add_bh(ip->i_gl, bh, 1);
800 		gfs2_inum_range_out(&ir,
801 				    bh->b_data + sizeof(struct gfs2_dinode));
802 		brelse(bh);
803 		mutex_unlock(&sdp->sd_inum_mutex);
804 		gfs2_trans_end(sdp);
805 		return 0;
806 	}
807 
808 	brelse(bh);
809 
810 	mutex_unlock(&sdp->sd_inum_mutex);
811 	gfs2_trans_end(sdp);
812 
813 	return 1;
814 }
815 
816 static int pick_formal_ino_2(struct gfs2_sbd *sdp, uint64_t *formal_ino)
817 {
818 	struct gfs2_inode *ip = get_v2ip(sdp->sd_ir_inode);
819 	struct gfs2_inode *m_ip = get_v2ip(sdp->sd_inum_inode);
820 	struct gfs2_holder gh;
821 	struct buffer_head *bh;
822 	struct gfs2_inum_range ir;
823 	int error;
824 
825 	error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
826 	if (error)
827 		return error;
828 
829 	error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
830 	if (error)
831 		goto out;
832 	mutex_lock(&sdp->sd_inum_mutex);
833 
834 	error = gfs2_meta_inode_buffer(ip, &bh);
835 	if (error)
836 		goto out_end_trans;
837 
838 	gfs2_inum_range_in(&ir, bh->b_data + sizeof(struct gfs2_dinode));
839 
840 	if (!ir.ir_length) {
841 		struct buffer_head *m_bh;
842 		uint64_t x, y;
843 
844 		error = gfs2_meta_inode_buffer(m_ip, &m_bh);
845 		if (error)
846 			goto out_brelse;
847 
848 		x = *(uint64_t *)(m_bh->b_data + sizeof(struct gfs2_dinode));
849 		x = y = be64_to_cpu(x);
850 		ir.ir_start = x;
851 		ir.ir_length = GFS2_INUM_QUANTUM;
852 		x += GFS2_INUM_QUANTUM;
853 		if (x < y)
854 			gfs2_consist_inode(m_ip);
855 		x = cpu_to_be64(x);
856 		gfs2_trans_add_bh(m_ip->i_gl, m_bh, 1);
857 		*(uint64_t *)(m_bh->b_data + sizeof(struct gfs2_dinode)) = x;
858 
859 		brelse(m_bh);
860 	}
861 
862 	*formal_ino = ir.ir_start++;
863 	ir.ir_length--;
864 
865 	gfs2_trans_add_bh(ip->i_gl, bh, 1);
866 	gfs2_inum_range_out(&ir, bh->b_data + sizeof(struct gfs2_dinode));
867 
868  out_brelse:
869 	brelse(bh);
870 
871  out_end_trans:
872 	mutex_unlock(&sdp->sd_inum_mutex);
873 	gfs2_trans_end(sdp);
874 
875  out:
876 	gfs2_glock_dq_uninit(&gh);
877 
878 	return error;
879 }
880 
881 static int pick_formal_ino(struct gfs2_sbd *sdp, uint64_t *inum)
882 {
883 	int error;
884 
885 	error = pick_formal_ino_1(sdp, inum);
886 	if (error <= 0)
887 		return error;
888 
889 	error = pick_formal_ino_2(sdp, inum);
890 
891 	return error;
892 }
893 
894 /**
895  * create_ok - OK to create a new on-disk inode here?
896  * @dip:  Directory in which dinode is to be created
897  * @name:  Name of new dinode
898  * @mode:
899  *
900  * Returns: errno
901  */
902 
903 static int create_ok(struct gfs2_inode *dip, struct qstr *name,
904 		     unsigned int mode)
905 {
906 	int error;
907 
908 	error = gfs2_repermission(dip->i_vnode, MAY_WRITE | MAY_EXEC, NULL);
909 	if (error)
910 		return error;
911 
912 	/*  Don't create entries in an unlinked directory  */
913 	if (!dip->i_di.di_nlink)
914 		return -EPERM;
915 
916 	error = gfs2_dir_search(dip, name, NULL, NULL);
917 	switch (error) {
918 	case -ENOENT:
919 		error = 0;
920 		break;
921 	case 0:
922 		return -EEXIST;
923 	default:
924 		return error;
925 	}
926 
927 	if (dip->i_di.di_entries == (uint32_t)-1)
928 		return -EFBIG;
929 	if (S_ISDIR(mode) && dip->i_di.di_nlink == (uint32_t)-1)
930 		return -EMLINK;
931 
932 	return 0;
933 }
934 
935 static void munge_mode_uid_gid(struct gfs2_inode *dip, unsigned int *mode,
936 			       unsigned int *uid, unsigned int *gid)
937 {
938 	if (dip->i_sbd->sd_args.ar_suiddir &&
939 	    (dip->i_di.di_mode & S_ISUID) &&
940 	    dip->i_di.di_uid) {
941 		if (S_ISDIR(*mode))
942 			*mode |= S_ISUID;
943 		else if (dip->i_di.di_uid != current->fsuid)
944 			*mode &= ~07111;
945 		*uid = dip->i_di.di_uid;
946 	} else
947 		*uid = current->fsuid;
948 
949 	if (dip->i_di.di_mode & S_ISGID) {
950 		if (S_ISDIR(*mode))
951 			*mode |= S_ISGID;
952 		*gid = dip->i_di.di_gid;
953 	} else
954 		*gid = current->fsgid;
955 }
956 
957 static int alloc_dinode(struct gfs2_inode *dip, struct gfs2_unlinked *ul)
958 {
959 	struct gfs2_sbd *sdp = dip->i_sbd;
960 	int error;
961 
962 	gfs2_alloc_get(dip);
963 
964 	dip->i_alloc.al_requested = RES_DINODE;
965 	error = gfs2_inplace_reserve(dip);
966 	if (error)
967 		goto out;
968 
969 	error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_UNLINKED +
970 				 RES_STATFS, 0);
971 	if (error)
972 		goto out_ipreserv;
973 
974 	ul->ul_ut.ut_inum.no_addr = gfs2_alloc_di(dip);
975 
976 	ul->ul_ut.ut_flags = GFS2_UTF_UNINIT;
977 	error = gfs2_unlinked_ondisk_add(sdp, ul);
978 
979 	gfs2_trans_end(sdp);
980 
981  out_ipreserv:
982 	gfs2_inplace_release(dip);
983 
984  out:
985 	gfs2_alloc_put(dip);
986 
987 	return error;
988 }
989 
990 /**
991  * init_dinode - Fill in a new dinode structure
992  * @dip: the directory this inode is being created in
993  * @gl: The glock covering the new inode
994  * @inum: the inode number
995  * @mode: the file permissions
996  * @uid:
997  * @gid:
998  *
999  */
1000 
1001 static void init_dinode(struct gfs2_inode *dip, struct gfs2_glock *gl,
1002 			struct gfs2_inum *inum, unsigned int mode,
1003 			unsigned int uid, unsigned int gid)
1004 {
1005 	struct gfs2_sbd *sdp = dip->i_sbd;
1006 	struct gfs2_dinode *di;
1007 	struct buffer_head *dibh;
1008 
1009 	dibh = gfs2_meta_new(gl, inum->no_addr);
1010 	gfs2_trans_add_bh(gl, dibh, 1);
1011 	gfs2_metatype_set(dibh, GFS2_METATYPE_DI, GFS2_FORMAT_DI);
1012 	gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
1013 	di = (struct gfs2_dinode *)dibh->b_data;
1014 
1015 	di->di_num.no_formal_ino = cpu_to_be64(inum->no_formal_ino);
1016 	di->di_num.no_addr = cpu_to_be64(inum->no_addr);
1017 	di->di_mode = cpu_to_be32(mode);
1018 	di->di_uid = cpu_to_be32(uid);
1019 	di->di_gid = cpu_to_be32(gid);
1020 	di->di_nlink = cpu_to_be32(0);
1021 	di->di_size = cpu_to_be64(0);
1022 	di->di_blocks = cpu_to_be64(1);
1023 	di->di_atime = di->di_mtime = di->di_ctime = cpu_to_be64(get_seconds());
1024 	di->di_major = di->di_minor = cpu_to_be32(0);
1025 	di->di_goal_meta = di->di_goal_data = cpu_to_be64(inum->no_addr);
1026 	di->__pad[0] = di->__pad[1] = 0;
1027 	di->di_flags = cpu_to_be32(0);
1028 
1029 	if (S_ISREG(mode)) {
1030 		if ((dip->i_di.di_flags & GFS2_DIF_INHERIT_JDATA) ||
1031 		    gfs2_tune_get(sdp, gt_new_files_jdata))
1032 			di->di_flags |= cpu_to_be32(GFS2_DIF_JDATA);
1033 		if ((dip->i_di.di_flags & GFS2_DIF_INHERIT_DIRECTIO) ||
1034 		    gfs2_tune_get(sdp, gt_new_files_directio))
1035 			di->di_flags |= cpu_to_be32(GFS2_DIF_DIRECTIO);
1036 	} else if (S_ISDIR(mode)) {
1037 		di->di_flags |= cpu_to_be32(dip->i_di.di_flags & GFS2_DIF_INHERIT_DIRECTIO);
1038 		di->di_flags |= cpu_to_be32(dip->i_di.di_flags & GFS2_DIF_INHERIT_JDATA);
1039 	}
1040 
1041 	di->__pad1 = 0;
1042 	di->di_height = cpu_to_be32(0);
1043 	di->__pad2 = 0;
1044 	di->__pad3 = 0;
1045 	di->di_depth = cpu_to_be16(0);
1046 	di->di_entries = cpu_to_be32(0);
1047 	memset(&di->__pad4, 0, sizeof(di->__pad4));
1048 	di->di_eattr = cpu_to_be64(0);
1049 	memset(&di->di_reserved, 0, sizeof(di->di_reserved));
1050 
1051 	brelse(dibh);
1052 }
1053 
1054 static int make_dinode(struct gfs2_inode *dip, struct gfs2_glock *gl,
1055 		       unsigned int mode, struct gfs2_unlinked *ul)
1056 {
1057 	struct gfs2_sbd *sdp = dip->i_sbd;
1058 	unsigned int uid, gid;
1059 	int error;
1060 
1061 	munge_mode_uid_gid(dip, &mode, &uid, &gid);
1062 
1063 	gfs2_alloc_get(dip);
1064 
1065 	error = gfs2_quota_lock(dip, uid, gid);
1066 	if (error)
1067 		goto out;
1068 
1069 	error = gfs2_quota_check(dip, uid, gid);
1070 	if (error)
1071 		goto out_quota;
1072 
1073 	error = gfs2_trans_begin(sdp, RES_DINODE + RES_UNLINKED +
1074 				 RES_QUOTA, 0);
1075 	if (error)
1076 		goto out_quota;
1077 
1078 	ul->ul_ut.ut_flags = 0;
1079 	error = gfs2_unlinked_ondisk_munge(sdp, ul);
1080 
1081 	init_dinode(dip, gl, &ul->ul_ut.ut_inum,
1082 		     mode, uid, gid);
1083 
1084 	gfs2_quota_change(dip, +1, uid, gid);
1085 
1086 	gfs2_trans_end(sdp);
1087 
1088  out_quota:
1089 	gfs2_quota_unlock(dip);
1090 
1091  out:
1092 	gfs2_alloc_put(dip);
1093 
1094 	return error;
1095 }
1096 
1097 static int link_dinode(struct gfs2_inode *dip, struct qstr *name,
1098 		       struct gfs2_inode *ip, struct gfs2_unlinked *ul)
1099 {
1100 	struct gfs2_sbd *sdp = dip->i_sbd;
1101 	struct gfs2_alloc *al;
1102 	int alloc_required;
1103 	struct buffer_head *dibh;
1104 	int error;
1105 
1106 	al = gfs2_alloc_get(dip);
1107 
1108 	error = gfs2_quota_lock(dip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
1109 	if (error)
1110 		goto fail;
1111 
1112 	error = gfs2_diradd_alloc_required(dip, name, &alloc_required);
1113 	if (alloc_required) {
1114 		error = gfs2_quota_check(dip, dip->i_di.di_uid,
1115 					 dip->i_di.di_gid);
1116 		if (error)
1117 			goto fail_quota_locks;
1118 
1119 		al->al_requested = sdp->sd_max_dirres;
1120 
1121 		error = gfs2_inplace_reserve(dip);
1122 		if (error)
1123 			goto fail_quota_locks;
1124 
1125 		error = gfs2_trans_begin(sdp,
1126 					 sdp->sd_max_dirres +
1127 					 al->al_rgd->rd_ri.ri_length +
1128 					 2 * RES_DINODE + RES_UNLINKED +
1129 					 RES_STATFS + RES_QUOTA, 0);
1130 		if (error)
1131 			goto fail_ipreserv;
1132 	} else {
1133 		error = gfs2_trans_begin(sdp,
1134 					 RES_LEAF +
1135 					 2 * RES_DINODE +
1136 					 RES_UNLINKED, 0);
1137 		if (error)
1138 			goto fail_quota_locks;
1139 	}
1140 
1141 	error = gfs2_dir_add(dip, name, &ip->i_num, IF2DT(ip->i_di.di_mode));
1142 	if (error)
1143 		goto fail_end_trans;
1144 
1145 	error = gfs2_meta_inode_buffer(ip, &dibh);
1146 	if (error)
1147 		goto fail_end_trans;
1148 	ip->i_di.di_nlink = 1;
1149 	gfs2_trans_add_bh(ip->i_gl, dibh, 1);
1150 	gfs2_dinode_out(&ip->i_di, dibh->b_data);
1151 	brelse(dibh);
1152 
1153 	error = gfs2_unlinked_ondisk_rm(sdp, ul);
1154 	if (error)
1155 		goto fail_end_trans;
1156 
1157 	return 0;
1158 
1159  fail_end_trans:
1160 	gfs2_trans_end(sdp);
1161 
1162  fail_ipreserv:
1163 	if (dip->i_alloc.al_rgd)
1164 		gfs2_inplace_release(dip);
1165 
1166  fail_quota_locks:
1167 	gfs2_quota_unlock(dip);
1168 
1169  fail:
1170 	gfs2_alloc_put(dip);
1171 
1172 	return error;
1173 }
1174 
1175 /**
1176  * gfs2_createi - Create a new inode
1177  * @ghs: An array of two holders
1178  * @name: The name of the new file
1179  * @mode: the permissions on the new inode
1180  *
1181  * @ghs[0] is an initialized holder for the directory
1182  * @ghs[1] is the holder for the inode lock
1183  *
1184  * If the return value is not NULL, the glocks on both the directory and the new
1185  * file are held.  A transaction has been started and an inplace reservation
1186  * is held, as well.
1187  *
1188  * Returns: An inode
1189  */
1190 
1191 struct inode *gfs2_createi(struct gfs2_holder *ghs, struct qstr *name, unsigned int mode)
1192 {
1193 	struct inode *inode;
1194 	struct gfs2_inode *dip = get_gl2ip(ghs->gh_gl);
1195 	struct gfs2_sbd *sdp = dip->i_sbd;
1196 	struct gfs2_unlinked *ul;
1197 	struct gfs2_inode *ip;
1198 	int error;
1199 
1200 	if (!name->len || name->len > GFS2_FNAMESIZE)
1201 		return ERR_PTR(-ENAMETOOLONG);
1202 
1203 	error = gfs2_unlinked_get(sdp, &ul);
1204 	if (error)
1205 		return ERR_PTR(error);
1206 
1207 	gfs2_holder_reinit(LM_ST_EXCLUSIVE, 0, ghs);
1208 	error = gfs2_glock_nq(ghs);
1209 	if (error)
1210 		goto fail;
1211 
1212 	error = create_ok(dip, name, mode);
1213 	if (error)
1214 		goto fail_gunlock;
1215 
1216 	error = pick_formal_ino(sdp, &ul->ul_ut.ut_inum.no_formal_ino);
1217 	if (error)
1218 		goto fail_gunlock;
1219 
1220 	error = alloc_dinode(dip, ul);
1221 	if (error)
1222 		goto fail_gunlock;
1223 
1224 	if (ul->ul_ut.ut_inum.no_addr < dip->i_num.no_addr) {
1225 		gfs2_glock_dq(ghs);
1226 
1227 		error = gfs2_glock_nq_num(sdp,
1228 					  ul->ul_ut.ut_inum.no_addr,
1229 					  &gfs2_inode_glops,
1230 					  LM_ST_EXCLUSIVE, GL_SKIP,
1231 					  ghs + 1);
1232 		if (error) {
1233 			gfs2_unlinked_put(sdp, ul);
1234 			return ERR_PTR(error);
1235 		}
1236 
1237 		gfs2_holder_reinit(LM_ST_EXCLUSIVE, 0, ghs);
1238 		error = gfs2_glock_nq(ghs);
1239 		if (error) {
1240 			gfs2_glock_dq_uninit(ghs + 1);
1241 			gfs2_unlinked_put(sdp, ul);
1242 			return ERR_PTR(error);
1243 		}
1244 
1245 		error = create_ok(dip, name, mode);
1246 		if (error)
1247 			goto fail_gunlock2;
1248 	} else {
1249 		error = gfs2_glock_nq_num(sdp,
1250 					  ul->ul_ut.ut_inum.no_addr,
1251 					  &gfs2_inode_glops,
1252 					  LM_ST_EXCLUSIVE, GL_SKIP,
1253 					  ghs + 1);
1254 		if (error)
1255 			goto fail_gunlock;
1256 	}
1257 
1258 	error = make_dinode(dip, ghs[1].gh_gl, mode, ul);
1259 	if (error)
1260 		goto fail_gunlock2;
1261 
1262 	error = gfs2_inode_get(ghs[1].gh_gl, &ul->ul_ut.ut_inum, CREATE, &ip);
1263 	if (error)
1264 		goto fail_gunlock2;
1265 
1266 	error = gfs2_inode_refresh(ip);
1267 	if (error)
1268 		goto fail_iput;
1269 
1270 	error = gfs2_acl_create(dip, ip);
1271 	if (error)
1272 		goto fail_iput;
1273 
1274 	error = link_dinode(dip, name, ip, ul);
1275 	if (error)
1276 		goto fail_iput;
1277 
1278 	gfs2_unlinked_put(sdp, ul);
1279 
1280 	inode = gfs2_ip2v(ip);
1281 	gfs2_inode_put(ip);
1282 	if (!inode)
1283 		return ERR_PTR(-ENOMEM);
1284 	return inode;
1285 
1286  fail_iput:
1287 	gfs2_inode_put(ip);
1288 
1289  fail_gunlock2:
1290 	gfs2_glock_dq_uninit(ghs + 1);
1291 
1292  fail_gunlock:
1293 	gfs2_glock_dq(ghs);
1294 
1295  fail:
1296 	gfs2_unlinked_put(sdp, ul);
1297 
1298 	return ERR_PTR(error);
1299 }
1300 
1301 /**
1302  * gfs2_unlinki - Unlink a file
1303  * @dip: The inode of the directory
1304  * @name: The name of the file to be unlinked
1305  * @ip: The inode of the file to be removed
1306  *
1307  * Assumes Glocks on both dip and ip are held.
1308  *
1309  * Returns: errno
1310  */
1311 
1312 int gfs2_unlinki(struct gfs2_inode *dip, struct qstr *name,
1313 		 struct gfs2_inode *ip, struct gfs2_unlinked *ul)
1314 {
1315 	struct gfs2_sbd *sdp = dip->i_sbd;
1316 	int error;
1317 
1318 	error = gfs2_dir_del(dip, name);
1319 	if (error)
1320 		return error;
1321 
1322 	error = gfs2_change_nlink(ip, -1);
1323 	if (error)
1324 		return error;
1325 
1326 	/* If this inode is being unlinked from the directory structure,
1327 	   we need to mark that in the log so that it isn't lost during
1328 	   a crash. */
1329 
1330 	if (!ip->i_di.di_nlink) {
1331 		ul->ul_ut.ut_inum = ip->i_num;
1332 		error = gfs2_unlinked_ondisk_add(sdp, ul);
1333 		if (!error)
1334 			set_bit(GLF_STICKY, &ip->i_gl->gl_flags);
1335 	}
1336 
1337 	return error;
1338 }
1339 
1340 /**
1341  * gfs2_rmdiri - Remove a directory
1342  * @dip: The parent directory of the directory to be removed
1343  * @name: The name of the directory to be removed
1344  * @ip: The GFS2 inode of the directory to be removed
1345  *
1346  * Assumes Glocks on dip and ip are held
1347  *
1348  * Returns: errno
1349  */
1350 
1351 int gfs2_rmdiri(struct gfs2_inode *dip, struct qstr *name,
1352 		struct gfs2_inode *ip, struct gfs2_unlinked *ul)
1353 {
1354 	struct gfs2_sbd *sdp = dip->i_sbd;
1355 	struct qstr dotname;
1356 	int error;
1357 
1358 	if (ip->i_di.di_entries != 2) {
1359 		if (gfs2_consist_inode(ip))
1360 			gfs2_dinode_print(&ip->i_di);
1361 		return -EIO;
1362 	}
1363 
1364 	error = gfs2_dir_del(dip, name);
1365 	if (error)
1366 		return error;
1367 
1368 	error = gfs2_change_nlink(dip, -1);
1369 	if (error)
1370 		return error;
1371 
1372 	dotname.len = 1;
1373 	dotname.name = ".";
1374 	error = gfs2_dir_del(ip, &dotname);
1375 	if (error)
1376 		return error;
1377 
1378 	dotname.len = 2;
1379 	dotname.name = "..";
1380 	error = gfs2_dir_del(ip, &dotname);
1381 	if (error)
1382 		return error;
1383 
1384 	error = gfs2_change_nlink(ip, -2);
1385 	if (error)
1386 		return error;
1387 
1388 	/* This inode is being unlinked from the directory structure and
1389 	   we need to mark that in the log so that it isn't lost during
1390 	   a crash. */
1391 
1392 	ul->ul_ut.ut_inum = ip->i_num;
1393 	error = gfs2_unlinked_ondisk_add(sdp, ul);
1394 	if (!error)
1395 		set_bit(GLF_STICKY, &ip->i_gl->gl_flags);
1396 
1397 	return error;
1398 }
1399 
1400 /*
1401  * gfs2_unlink_ok - check to see that a inode is still in a directory
1402  * @dip: the directory
1403  * @name: the name of the file
1404  * @ip: the inode
1405  *
1406  * Assumes that the lock on (at least) @dip is held.
1407  *
1408  * Returns: 0 if the parent/child relationship is correct, errno if it isn't
1409  */
1410 
1411 int gfs2_unlink_ok(struct gfs2_inode *dip, struct qstr *name,
1412 		   struct gfs2_inode *ip)
1413 {
1414 	struct gfs2_inum inum;
1415 	unsigned int type;
1416 	int error;
1417 
1418 	if (IS_IMMUTABLE(ip->i_vnode) || IS_APPEND(ip->i_vnode))
1419 		return -EPERM;
1420 
1421 	if ((dip->i_di.di_mode & S_ISVTX) &&
1422 	    dip->i_di.di_uid != current->fsuid &&
1423 	    ip->i_di.di_uid != current->fsuid &&
1424 	    !capable(CAP_FOWNER))
1425 		return -EPERM;
1426 
1427 	if (IS_APPEND(dip->i_vnode))
1428 		return -EPERM;
1429 
1430 	error = gfs2_repermission(dip->i_vnode, MAY_WRITE | MAY_EXEC, NULL);
1431 	if (error)
1432 		return error;
1433 
1434 	error = gfs2_dir_search(dip, name, &inum, &type);
1435 	if (error)
1436 		return error;
1437 
1438 	if (!gfs2_inum_equal(&inum, &ip->i_num))
1439 		return -ENOENT;
1440 
1441 	if (IF2DT(ip->i_di.di_mode) != type) {
1442 		gfs2_consist_inode(dip);
1443 		return -EIO;
1444 	}
1445 
1446 	return 0;
1447 }
1448 
1449 /*
1450  * gfs2_ok_to_move - check if it's ok to move a directory to another directory
1451  * @this: move this
1452  * @to: to here
1453  *
1454  * Follow @to back to the root and make sure we don't encounter @this
1455  * Assumes we already hold the rename lock.
1456  *
1457  * Returns: errno
1458  */
1459 
1460 int gfs2_ok_to_move(struct gfs2_inode *this, struct gfs2_inode *to)
1461 {
1462 	struct gfs2_sbd *sdp = this->i_sbd;
1463 	struct inode *dir = to->i_vnode;
1464 	struct inode *tmp;
1465 	struct qstr dotdot;
1466 	int error = 0;
1467 
1468 	memset(&dotdot, 0, sizeof(struct qstr));
1469 	dotdot.name = "..";
1470 	dotdot.len = 2;
1471 
1472 	igrab(dir);
1473 
1474 	for (;;) {
1475 		if (dir == this->i_vnode) {
1476 			error = -EINVAL;
1477 			break;
1478 		}
1479 		if (dir == sdp->sd_root_dir) {
1480 			error = 0;
1481 			break;
1482 		}
1483 
1484 		error = gfs2_lookupi(dir, &dotdot, 1, &tmp);
1485 		if (error)
1486 			break;
1487 
1488 		iput(dir);
1489 		dir = tmp;
1490 	}
1491 
1492 	iput(dir);
1493 
1494 	return error;
1495 }
1496 
1497 /**
1498  * gfs2_readlinki - return the contents of a symlink
1499  * @ip: the symlink's inode
1500  * @buf: a pointer to the buffer to be filled
1501  * @len: a pointer to the length of @buf
1502  *
1503  * If @buf is too small, a piece of memory is kmalloc()ed and needs
1504  * to be freed by the caller.
1505  *
1506  * Returns: errno
1507  */
1508 
1509 int gfs2_readlinki(struct gfs2_inode *ip, char **buf, unsigned int *len)
1510 {
1511 	struct gfs2_holder i_gh;
1512 	struct buffer_head *dibh;
1513 	unsigned int x;
1514 	int error;
1515 
1516 	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &i_gh);
1517 	error = gfs2_glock_nq_atime(&i_gh);
1518 	if (error) {
1519 		gfs2_holder_uninit(&i_gh);
1520 		return error;
1521 	}
1522 
1523 	if (!ip->i_di.di_size) {
1524 		gfs2_consist_inode(ip);
1525 		error = -EIO;
1526 		goto out;
1527 	}
1528 
1529 	error = gfs2_meta_inode_buffer(ip, &dibh);
1530 	if (error)
1531 		goto out;
1532 
1533 	x = ip->i_di.di_size + 1;
1534 	if (x > *len) {
1535 		*buf = kmalloc(x, GFP_KERNEL);
1536 		if (!*buf) {
1537 			error = -ENOMEM;
1538 			goto out_brelse;
1539 		}
1540 	}
1541 
1542 	memcpy(*buf, dibh->b_data + sizeof(struct gfs2_dinode), x);
1543 	*len = x;
1544 
1545  out_brelse:
1546 	brelse(dibh);
1547 
1548  out:
1549 	gfs2_glock_dq_uninit(&i_gh);
1550 
1551 	return error;
1552 }
1553 
1554 /**
1555  * gfs2_glock_nq_atime - Acquire a hold on an inode's glock, and
1556  *       conditionally update the inode's atime
1557  * @gh: the holder to acquire
1558  *
1559  * Tests atime (access time) for gfs2_read, gfs2_readdir and gfs2_mmap
1560  * Update if the difference between the current time and the inode's current
1561  * atime is greater than an interval specified at mount.
1562  *
1563  * Returns: errno
1564  */
1565 
1566 int gfs2_glock_nq_atime(struct gfs2_holder *gh)
1567 {
1568 	struct gfs2_glock *gl = gh->gh_gl;
1569 	struct gfs2_sbd *sdp = gl->gl_sbd;
1570 	struct gfs2_inode *ip = get_gl2ip(gl);
1571 	int64_t curtime, quantum = gfs2_tune_get(sdp, gt_atime_quantum);
1572 	unsigned int state;
1573 	int flags;
1574 	int error;
1575 
1576 	if (gfs2_assert_warn(sdp, gh->gh_flags & GL_ATIME) ||
1577 	    gfs2_assert_warn(sdp, !(gh->gh_flags & GL_ASYNC)) ||
1578 	    gfs2_assert_warn(sdp, gl->gl_ops == &gfs2_inode_glops))
1579 		return -EINVAL;
1580 
1581 	state = gh->gh_state;
1582 	flags = gh->gh_flags;
1583 
1584 	error = gfs2_glock_nq(gh);
1585 	if (error)
1586 		return error;
1587 
1588 	if (test_bit(SDF_NOATIME, &sdp->sd_flags) ||
1589 	    (sdp->sd_vfs->s_flags & MS_RDONLY))
1590 		return 0;
1591 
1592 	curtime = get_seconds();
1593 	if (curtime - ip->i_di.di_atime >= quantum) {
1594 		gfs2_glock_dq(gh);
1595 		gfs2_holder_reinit(LM_ST_EXCLUSIVE,
1596 				  gh->gh_flags & ~LM_FLAG_ANY,
1597 				  gh);
1598 		error = gfs2_glock_nq(gh);
1599 		if (error)
1600 			return error;
1601 
1602 		/* Verify that atime hasn't been updated while we were
1603 		   trying to get exclusive lock. */
1604 
1605 		curtime = get_seconds();
1606 		if (curtime - ip->i_di.di_atime >= quantum) {
1607 			struct buffer_head *dibh;
1608 
1609 			error = gfs2_trans_begin(sdp, RES_DINODE, 0);
1610 			if (error == -EROFS)
1611 				return 0;
1612 			if (error)
1613 				goto fail;
1614 
1615 			error = gfs2_meta_inode_buffer(ip, &dibh);
1616 			if (error)
1617 				goto fail_end_trans;
1618 
1619 			ip->i_di.di_atime = curtime;
1620 
1621 			gfs2_trans_add_bh(ip->i_gl, dibh, 1);
1622 			gfs2_dinode_out(&ip->i_di, dibh->b_data);
1623 			brelse(dibh);
1624 
1625 			gfs2_trans_end(sdp);
1626 		}
1627 
1628 		/* If someone else has asked for the glock,
1629 		   unlock and let them have it. Then reacquire
1630 		   in the original state. */
1631 		if (gfs2_glock_is_blocking(gl)) {
1632 			gfs2_glock_dq(gh);
1633 			gfs2_holder_reinit(state, flags, gh);
1634 			return gfs2_glock_nq(gh);
1635 		}
1636 	}
1637 
1638 	return 0;
1639 
1640  fail_end_trans:
1641 	gfs2_trans_end(sdp);
1642 
1643  fail:
1644 	gfs2_glock_dq(gh);
1645 
1646 	return error;
1647 }
1648 
1649 /**
1650  * glock_compare_atime - Compare two struct gfs2_glock structures for sort
1651  * @arg_a: the first structure
1652  * @arg_b: the second structure
1653  *
1654  * Returns: 1 if A > B
1655  *         -1 if A < B
1656  *          0 if A = B
1657  */
1658 
1659 static int glock_compare_atime(const void *arg_a, const void *arg_b)
1660 {
1661 	struct gfs2_holder *gh_a = *(struct gfs2_holder **)arg_a;
1662 	struct gfs2_holder *gh_b = *(struct gfs2_holder **)arg_b;
1663 	struct lm_lockname *a = &gh_a->gh_gl->gl_name;
1664 	struct lm_lockname *b = &gh_b->gh_gl->gl_name;
1665 	int ret = 0;
1666 
1667 	if (a->ln_number > b->ln_number)
1668 		ret = 1;
1669 	else if (a->ln_number < b->ln_number)
1670 		ret = -1;
1671 	else {
1672 		if (gh_a->gh_state == LM_ST_SHARED &&
1673 		    gh_b->gh_state == LM_ST_EXCLUSIVE)
1674 			ret = 1;
1675 		else if (gh_a->gh_state == LM_ST_SHARED &&
1676 			 (gh_b->gh_flags & GL_ATIME))
1677 			ret = 1;
1678 	}
1679 
1680 	return ret;
1681 }
1682 
1683 /**
1684  * gfs2_glock_nq_m_atime - acquire multiple glocks where one may need an
1685  *      atime update
1686  * @num_gh: the number of structures
1687  * @ghs: an array of struct gfs2_holder structures
1688  *
1689  * Returns: 0 on success (all glocks acquired),
1690  *          errno on failure (no glocks acquired)
1691  */
1692 
1693 int gfs2_glock_nq_m_atime(unsigned int num_gh, struct gfs2_holder *ghs)
1694 {
1695 	struct gfs2_holder **p;
1696 	unsigned int x;
1697 	int error = 0;
1698 
1699 	if (!num_gh)
1700 		return 0;
1701 
1702 	if (num_gh == 1) {
1703 		ghs->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC);
1704 		if (ghs->gh_flags & GL_ATIME)
1705 			error = gfs2_glock_nq_atime(ghs);
1706 		else
1707 			error = gfs2_glock_nq(ghs);
1708 		return error;
1709 	}
1710 
1711 	p = kcalloc(num_gh, sizeof(struct gfs2_holder *), GFP_KERNEL);
1712 	if (!p)
1713 		return -ENOMEM;
1714 
1715 	for (x = 0; x < num_gh; x++)
1716 		p[x] = &ghs[x];
1717 
1718 	sort(p, num_gh, sizeof(struct gfs2_holder *), glock_compare_atime,NULL);
1719 
1720 	for (x = 0; x < num_gh; x++) {
1721 		p[x]->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC);
1722 
1723 		if (p[x]->gh_flags & GL_ATIME)
1724 			error = gfs2_glock_nq_atime(p[x]);
1725 		else
1726 			error = gfs2_glock_nq(p[x]);
1727 
1728 		if (error) {
1729 			while (x--)
1730 				gfs2_glock_dq(p[x]);
1731 			break;
1732 		}
1733 	}
1734 
1735 	kfree(p);
1736 
1737 	return error;
1738 }
1739 
1740 /**
1741  * gfs2_try_toss_vnode - See if we can toss a vnode from memory
1742  * @ip: the inode
1743  *
1744  * Returns:  1 if the vnode was tossed
1745  */
1746 
1747 void gfs2_try_toss_vnode(struct gfs2_inode *ip)
1748 {
1749 	struct inode *inode;
1750 
1751 	inode = gfs2_ip2v_lookup(ip);
1752 	if (!inode)
1753 		return;
1754 
1755 	d_prune_aliases(inode);
1756 
1757 	if (S_ISDIR(ip->i_di.di_mode)) {
1758 		struct list_head *head = &inode->i_dentry;
1759 		struct dentry *d = NULL;
1760 
1761 		spin_lock(&dcache_lock);
1762 		if (list_empty(head))
1763 			spin_unlock(&dcache_lock);
1764 		else {
1765 			d = list_entry(head->next, struct dentry, d_alias);
1766 			dget_locked(d);
1767 			spin_unlock(&dcache_lock);
1768 
1769 			if (have_submounts(d))
1770 				dput(d);
1771 			else {
1772 				shrink_dcache_parent(d);
1773 				dput(d);
1774 				d_prune_aliases(inode);
1775 			}
1776 		}
1777 	}
1778 
1779 	inode->i_nlink = 0;
1780 	iput(inode);
1781 }
1782 
1783 
1784 static int
1785 __gfs2_setattr_simple(struct gfs2_inode *ip, struct iattr *attr)
1786 {
1787 	struct buffer_head *dibh;
1788 	int error;
1789 
1790 	error = gfs2_meta_inode_buffer(ip, &dibh);
1791 	if (!error) {
1792 		error = inode_setattr(ip->i_vnode, attr);
1793 		gfs2_assert_warn(ip->i_sbd, !error);
1794 		gfs2_inode_attr_out(ip);
1795 
1796 		gfs2_trans_add_bh(ip->i_gl, dibh, 1);
1797 		gfs2_dinode_out(&ip->i_di, dibh->b_data);
1798 		brelse(dibh);
1799 	}
1800 	return error;
1801 }
1802 
1803 /**
1804  * gfs2_setattr_simple -
1805  * @ip:
1806  * @attr:
1807  *
1808  * Called with a reference on the vnode.
1809  *
1810  * Returns: errno
1811  */
1812 
1813 int gfs2_setattr_simple(struct gfs2_inode *ip, struct iattr *attr)
1814 {
1815 	int error;
1816 
1817 	if (get_transaction)
1818 		return __gfs2_setattr_simple(ip, attr);
1819 
1820 	error = gfs2_trans_begin(ip->i_sbd, RES_DINODE, 0);
1821 	if (error)
1822 		return error;
1823 
1824 	error = __gfs2_setattr_simple(ip, attr);
1825 
1826 	gfs2_trans_end(ip->i_sbd);
1827 
1828 	return error;
1829 }
1830 
1831 int gfs2_repermission(struct inode *inode, int mask, struct nameidata *nd)
1832 {
1833 	return permission(inode, mask, nd);
1834 }
1835 
1836