xref: /openbmc/linux/fs/gfs2/inode.c (revision 71b86f56)
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 <linux/gfs2_ondisk.h>
18 #include <linux/crc32.h>
19 #include <asm/semaphore.h>
20 
21 #include "gfs2.h"
22 #include "lm_interface.h"
23 #include "incore.h"
24 #include "acl.h"
25 #include "bmap.h"
26 #include "dir.h"
27 #include "eattr.h"
28 #include "glock.h"
29 #include "glops.h"
30 #include "inode.h"
31 #include "log.h"
32 #include "meta_io.h"
33 #include "ops_address.h"
34 #include "ops_file.h"
35 #include "ops_inode.h"
36 #include "quota.h"
37 #include "rgrp.h"
38 #include "trans.h"
39 #include "unlinked.h"
40 #include "util.h"
41 
42 /**
43  * inode_attr_in - Copy attributes from the dinode into the VFS inode
44  * @ip: The GFS2 inode (with embedded disk inode data)
45  * @inode:  The Linux VFS inode
46  *
47  */
48 
49 static void inode_attr_in(struct gfs2_inode *ip, struct inode *inode)
50 {
51 	inode->i_ino = ip->i_num.no_formal_ino;
52 
53 	switch (ip->i_di.di_mode & S_IFMT) {
54 	case S_IFBLK:
55 	case S_IFCHR:
56 		inode->i_rdev = MKDEV(ip->i_di.di_major, ip->i_di.di_minor);
57 		break;
58 	default:
59 		inode->i_rdev = 0;
60 		break;
61 	};
62 
63 	inode->i_mode = ip->i_di.di_mode;
64 	inode->i_nlink = ip->i_di.di_nlink;
65 	inode->i_uid = ip->i_di.di_uid;
66 	inode->i_gid = ip->i_di.di_gid;
67 	i_size_write(inode, ip->i_di.di_size);
68 	inode->i_atime.tv_sec = ip->i_di.di_atime;
69 	inode->i_mtime.tv_sec = ip->i_di.di_mtime;
70 	inode->i_ctime.tv_sec = ip->i_di.di_ctime;
71 	inode->i_atime.tv_nsec = 0;
72 	inode->i_mtime.tv_nsec = 0;
73 	inode->i_ctime.tv_nsec = 0;
74 	inode->i_blksize = PAGE_SIZE;
75 	inode->i_blocks = ip->i_di.di_blocks <<
76 		(ip->i_sbd->sd_sb.sb_bsize_shift - GFS2_BASIC_BLOCK_SHIFT);
77 
78 	if (ip->i_di.di_flags & GFS2_DIF_IMMUTABLE)
79 		inode->i_flags |= S_IMMUTABLE;
80 	else
81 		inode->i_flags &= ~S_IMMUTABLE;
82 
83 	if (ip->i_di.di_flags & GFS2_DIF_APPENDONLY)
84 		inode->i_flags |= S_APPEND;
85 	else
86 		inode->i_flags &= ~S_APPEND;
87 }
88 
89 /**
90  * gfs2_inode_attr_in - Copy attributes from the dinode into the VFS inode
91  * @ip: The GFS2 inode (with embedded disk inode data)
92  *
93  */
94 
95 void gfs2_inode_attr_in(struct gfs2_inode *ip)
96 {
97 	struct inode *inode;
98 
99 	inode = gfs2_ip2v_lookup(ip);
100 	if (inode) {
101 		inode_attr_in(ip, inode);
102 		iput(inode);
103 	}
104 }
105 
106 /**
107  * gfs2_inode_attr_out - Copy attributes from VFS inode into the dinode
108  * @ip: The GFS2 inode
109  *
110  * Only copy out the attributes that we want the VFS layer
111  * to be able to modify.
112  */
113 
114 void gfs2_inode_attr_out(struct gfs2_inode *ip)
115 {
116 	struct inode *inode = ip->i_vnode;
117 
118 	gfs2_assert_withdraw(ip->i_sbd,
119 		(ip->i_di.di_mode & S_IFMT) == (inode->i_mode & S_IFMT));
120 	ip->i_di.di_mode = inode->i_mode;
121 	ip->i_di.di_uid = inode->i_uid;
122 	ip->i_di.di_gid = inode->i_gid;
123 	ip->i_di.di_atime = inode->i_atime.tv_sec;
124 	ip->i_di.di_mtime = inode->i_mtime.tv_sec;
125 	ip->i_di.di_ctime = inode->i_ctime.tv_sec;
126 }
127 
128 /**
129  * gfs2_ip2v_lookup - Get the struct inode for a struct gfs2_inode
130  * @ip: the struct gfs2_inode to get the struct inode for
131  *
132  * Returns: A VFS inode, or NULL if none
133  */
134 
135 struct inode *gfs2_ip2v_lookup(struct gfs2_inode *ip)
136 {
137 	struct inode *inode = NULL;
138 
139 	gfs2_assert_warn(ip->i_sbd, test_bit(GIF_MIN_INIT, &ip->i_flags));
140 
141 	spin_lock(&ip->i_spin);
142 	if (ip->i_vnode)
143 		inode = igrab(ip->i_vnode);
144 	spin_unlock(&ip->i_spin);
145 
146 	return inode;
147 }
148 
149 /**
150  * gfs2_ip2v - Get/Create a struct inode for a struct gfs2_inode
151  * @ip: the struct gfs2_inode to get the struct inode for
152  *
153  * Returns: A VFS inode, or NULL if no mem
154  */
155 
156 struct inode *gfs2_ip2v(struct gfs2_inode *ip)
157 {
158 	struct inode *inode, *tmp;
159 
160 	inode = gfs2_ip2v_lookup(ip);
161 	if (inode)
162 		return inode;
163 
164 	tmp = new_inode(ip->i_sbd->sd_vfs);
165 	if (!tmp)
166 		return NULL;
167 
168 	inode_attr_in(ip, tmp);
169 
170 	if (S_ISREG(ip->i_di.di_mode)) {
171 		tmp->i_op = &gfs2_file_iops;
172 		tmp->i_fop = &gfs2_file_fops;
173 		tmp->i_mapping->a_ops = &gfs2_file_aops;
174 	} else if (S_ISDIR(ip->i_di.di_mode)) {
175 		tmp->i_op = &gfs2_dir_iops;
176 		tmp->i_fop = &gfs2_dir_fops;
177 	} else if (S_ISLNK(ip->i_di.di_mode)) {
178 		tmp->i_op = &gfs2_symlink_iops;
179 	} else {
180 		tmp->i_op = &gfs2_dev_iops;
181 		init_special_inode(tmp, tmp->i_mode, tmp->i_rdev);
182 	}
183 
184 	tmp->u.generic_ip = NULL;
185 
186 	for (;;) {
187 		spin_lock(&ip->i_spin);
188 		if (!ip->i_vnode)
189 			break;
190 		inode = igrab(ip->i_vnode);
191 		spin_unlock(&ip->i_spin);
192 
193 		if (inode) {
194 			iput(tmp);
195 			return inode;
196 		}
197 		yield();
198 	}
199 
200 	inode = tmp;
201 
202 	gfs2_inode_hold(ip);
203 	ip->i_vnode = inode;
204 	inode->u.generic_ip = ip;
205 
206 	spin_unlock(&ip->i_spin);
207 
208 	insert_inode_hash(inode);
209 
210 	return inode;
211 }
212 
213 static int iget_test(struct inode *inode, void *opaque)
214 {
215 	struct gfs2_inode *ip = inode->u.generic_ip;
216 	struct gfs2_inum *inum = (struct gfs2_inum *)opaque;
217 
218 	if (ip && ip->i_num.no_addr == inum->no_addr)
219 		return 1;
220 
221 	return 0;
222 }
223 
224 struct inode *gfs2_iget(struct super_block *sb, struct gfs2_inum *inum)
225 {
226 	return ilookup5(sb, (unsigned long)inum->no_formal_ino,
227 			iget_test, inum);
228 }
229 
230 void gfs2_inode_min_init(struct gfs2_inode *ip, unsigned int type)
231 {
232 	if (!test_and_set_bit(GIF_MIN_INIT, &ip->i_flags)) {
233 		ip->i_di.di_nlink = 1;
234 		ip->i_di.di_mode = DT2IF(type);
235 	}
236 }
237 
238 /**
239  * gfs2_inode_refresh - Refresh the incore copy of the dinode
240  * @ip: The GFS2 inode
241  *
242  * Returns: errno
243  */
244 
245 int gfs2_inode_refresh(struct gfs2_inode *ip)
246 {
247 	struct buffer_head *dibh;
248 	int error;
249 
250 	error = gfs2_meta_inode_buffer(ip, &dibh);
251 	if (error)
252 		return error;
253 
254 	if (gfs2_metatype_check(ip->i_sbd, dibh, GFS2_METATYPE_DI)) {
255 		brelse(dibh);
256 		return -EIO;
257 	}
258 
259 	gfs2_dinode_in(&ip->i_di, dibh->b_data);
260 	set_bit(GIF_MIN_INIT, &ip->i_flags);
261 
262 	brelse(dibh);
263 
264 	if (ip->i_num.no_addr != ip->i_di.di_num.no_addr) {
265 		if (gfs2_consist_inode(ip))
266 			gfs2_dinode_print(&ip->i_di);
267 		return -EIO;
268 	}
269 	if (ip->i_num.no_formal_ino != ip->i_di.di_num.no_formal_ino)
270 		return -ESTALE;
271 
272 	ip->i_vn = ip->i_gl->gl_vn;
273 
274 	return 0;
275 }
276 
277 /**
278  * inode_create - create a struct gfs2_inode
279  * @i_gl: The glock covering the inode
280  * @inum: The inode number
281  * @io_gl: the iopen glock to acquire/hold (using holder in new gfs2_inode)
282  * @io_state: the state the iopen glock should be acquired in
283  * @ipp: pointer to put the returned inode in
284  *
285  * Returns: errno
286  */
287 
288 static int inode_create(struct gfs2_glock *i_gl, const struct gfs2_inum *inum,
289 			struct gfs2_glock *io_gl, unsigned int io_state,
290 			struct gfs2_inode **ipp)
291 {
292 	struct gfs2_sbd *sdp = i_gl->gl_sbd;
293 	struct gfs2_inode *ip;
294 	int error = 0;
295 
296 	ip = kmem_cache_alloc(gfs2_inode_cachep, GFP_KERNEL);
297 	if (!ip)
298 		return -ENOMEM;
299 	memset(ip, 0, sizeof(struct gfs2_inode));
300 
301 	ip->i_num = *inum;
302 
303 	atomic_set(&ip->i_count, 1);
304 
305 	ip->i_vn = i_gl->gl_vn - 1;
306 
307 	ip->i_gl = i_gl;
308 	ip->i_sbd = sdp;
309 
310 	spin_lock_init(&ip->i_spin);
311 	init_rwsem(&ip->i_rw_mutex);
312 
313 	ip->i_greedy = gfs2_tune_get(sdp, gt_greedy_default);
314 
315 	error = gfs2_glock_nq_init(io_gl,
316 				   io_state, GL_LOCAL_EXCL | GL_EXACT,
317 				   &ip->i_iopen_gh);
318 	if (error)
319 		goto fail;
320 	ip->i_iopen_gh.gh_owner = NULL;
321 
322 	spin_lock(&io_gl->gl_spin);
323 	gfs2_glock_hold(i_gl);
324 	io_gl->gl_object = i_gl;
325 	spin_unlock(&io_gl->gl_spin);
326 
327 	gfs2_glock_hold(i_gl);
328 	i_gl->gl_object = ip;
329 
330 	atomic_inc(&sdp->sd_inode_count);
331 
332 	*ipp = ip;
333 
334 	return 0;
335 
336  fail:
337 	gfs2_meta_cache_flush(ip);
338 	kmem_cache_free(gfs2_inode_cachep, ip);
339 	*ipp = NULL;
340 
341 	return error;
342 }
343 
344 /**
345  * gfs2_inode_get - Create or get a reference on an inode
346  * @i_gl: The glock covering the inode
347  * @inum: The inode number
348  * @create:
349  * @ipp: pointer to put the returned inode in
350  *
351  * Returns: errno
352  */
353 
354 int gfs2_inode_get(struct gfs2_glock *i_gl, const struct gfs2_inum *inum,
355 		   int create, struct gfs2_inode **ipp)
356 {
357 	struct gfs2_sbd *sdp = i_gl->gl_sbd;
358 	struct gfs2_glock *io_gl;
359 	int error = 0;
360 
361 	gfs2_glmutex_lock(i_gl);
362 
363 	*ipp = i_gl->gl_object;
364 	if (*ipp) {
365 		error = -ESTALE;
366 		if ((*ipp)->i_num.no_formal_ino != inum->no_formal_ino)
367 			goto out;
368 		atomic_inc(&(*ipp)->i_count);
369 		error = 0;
370 		goto out;
371 	}
372 
373 	if (!create)
374 		goto out;
375 
376 	error = gfs2_glock_get(sdp, inum->no_addr, &gfs2_iopen_glops,
377 			       CREATE, &io_gl);
378 	if (!error) {
379 		error = inode_create(i_gl, inum, io_gl, LM_ST_SHARED, ipp);
380 		gfs2_glock_put(io_gl);
381 	}
382 
383  out:
384 	gfs2_glmutex_unlock(i_gl);
385 
386 	return error;
387 }
388 
389 void gfs2_inode_hold(struct gfs2_inode *ip)
390 {
391 	gfs2_assert(ip->i_sbd, atomic_read(&ip->i_count) > 0);
392 	atomic_inc(&ip->i_count);
393 }
394 
395 void gfs2_inode_put(struct gfs2_inode *ip)
396 {
397 	gfs2_assert(ip->i_sbd, atomic_read(&ip->i_count) > 0);
398 	atomic_dec(&ip->i_count);
399 }
400 
401 void gfs2_inode_destroy(struct gfs2_inode *ip)
402 {
403 	struct gfs2_sbd *sdp = ip->i_sbd;
404 	struct gfs2_glock *io_gl = ip->i_iopen_gh.gh_gl;
405 	struct gfs2_glock *i_gl = ip->i_gl;
406 
407 	gfs2_assert_warn(sdp, !atomic_read(&ip->i_count));
408 	gfs2_assert(sdp, io_gl->gl_object == i_gl);
409 
410 	spin_lock(&io_gl->gl_spin);
411 	io_gl->gl_object = NULL;
412 	gfs2_glock_put(i_gl);
413 	spin_unlock(&io_gl->gl_spin);
414 
415 	gfs2_glock_dq_uninit(&ip->i_iopen_gh);
416 
417 	gfs2_meta_cache_flush(ip);
418 	kmem_cache_free(gfs2_inode_cachep, ip);
419 
420 	i_gl->gl_object = NULL;
421 	gfs2_glock_put(i_gl);
422 
423 	atomic_dec(&sdp->sd_inode_count);
424 }
425 
426 static int dinode_dealloc(struct gfs2_inode *ip, struct gfs2_unlinked *ul)
427 {
428 	struct gfs2_sbd *sdp = ip->i_sbd;
429 	struct gfs2_alloc *al;
430 	struct gfs2_rgrpd *rgd;
431 	int error;
432 
433 	if (ip->i_di.di_blocks != 1) {
434 		if (gfs2_consist_inode(ip))
435 			gfs2_dinode_print(&ip->i_di);
436 		return -EIO;
437 	}
438 
439 	al = gfs2_alloc_get(ip);
440 
441 	error = gfs2_quota_hold(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
442 	if (error)
443 		goto out;
444 
445 	error = gfs2_rindex_hold(sdp, &al->al_ri_gh);
446 	if (error)
447 		goto out_qs;
448 
449 	rgd = gfs2_blk2rgrpd(sdp, ip->i_num.no_addr);
450 	if (!rgd) {
451 		gfs2_consist_inode(ip);
452 		error = -EIO;
453 		goto out_rindex_relse;
454 	}
455 
456 	error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0,
457 				   &al->al_rgd_gh);
458 	if (error)
459 		goto out_rindex_relse;
460 
461 	error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_UNLINKED +
462 				 RES_STATFS + RES_QUOTA, 1);
463 	if (error)
464 		goto out_rg_gunlock;
465 
466 	gfs2_trans_add_gl(ip->i_gl);
467 
468 	gfs2_free_di(rgd, ip);
469 
470 	error = gfs2_unlinked_ondisk_rm(sdp, ul);
471 
472 	gfs2_trans_end(sdp);
473 	clear_bit(GLF_STICKY, &ip->i_gl->gl_flags);
474 
475  out_rg_gunlock:
476 	gfs2_glock_dq_uninit(&al->al_rgd_gh);
477 
478  out_rindex_relse:
479 	gfs2_glock_dq_uninit(&al->al_ri_gh);
480 
481  out_qs:
482 	gfs2_quota_unhold(ip);
483 
484  out:
485 	gfs2_alloc_put(ip);
486 
487 	return error;
488 }
489 
490 /**
491  * inode_dealloc - Deallocate all on-disk blocks for an inode (dinode)
492  * @sdp: the filesystem
493  * @inum: the inode number to deallocate
494  * @io_gh: a holder for the iopen glock for this inode
495  *
496  * Returns: errno
497  */
498 
499 static int inode_dealloc(struct gfs2_sbd *sdp, struct gfs2_unlinked *ul,
500 			 struct gfs2_holder *io_gh)
501 {
502 	struct gfs2_inode *ip;
503 	struct gfs2_holder i_gh;
504 	int error;
505 
506 	error = gfs2_glock_nq_num(sdp,
507 				  ul->ul_ut.ut_inum.no_addr, &gfs2_inode_glops,
508 				  LM_ST_EXCLUSIVE, 0, &i_gh);
509 	if (error)
510 		return error;
511 
512 	/* We reacquire the iopen lock here to avoid a race with the NFS server
513 	   calling gfs2_read_inode() with the inode number of a inode we're in
514 	   the process of deallocating.  And we can't keep our hold on the lock
515 	   from inode_dealloc_init() for deadlock reasons. */
516 
517 	gfs2_holder_reinit(LM_ST_EXCLUSIVE, LM_FLAG_TRY, io_gh);
518 	error = gfs2_glock_nq(io_gh);
519 	switch (error) {
520 	case 0:
521 		break;
522 	case GLR_TRYFAILED:
523 		error = 1;
524 	default:
525 		goto out;
526 	}
527 
528 	gfs2_assert_warn(sdp, !i_gh.gh_gl->gl_object);
529 	error = inode_create(i_gh.gh_gl, &ul->ul_ut.ut_inum, io_gh->gh_gl,
530 			     LM_ST_EXCLUSIVE, &ip);
531 
532 	gfs2_glock_dq(io_gh);
533 
534 	if (error)
535 		goto out;
536 
537 	error = gfs2_inode_refresh(ip);
538 	if (error)
539 		goto out_iput;
540 
541 	if (ip->i_di.di_nlink) {
542 		if (gfs2_consist_inode(ip))
543 			gfs2_dinode_print(&ip->i_di);
544 		error = -EIO;
545 		goto out_iput;
546 	}
547 
548 	if (S_ISDIR(ip->i_di.di_mode) &&
549 	    (ip->i_di.di_flags & GFS2_DIF_EXHASH)) {
550 		error = gfs2_dir_exhash_dealloc(ip);
551 		if (error)
552 			goto out_iput;
553 	}
554 
555 	if (ip->i_di.di_eattr) {
556 		error = gfs2_ea_dealloc(ip);
557 		if (error)
558 			goto out_iput;
559 	}
560 
561 	if (!gfs2_is_stuffed(ip)) {
562 		error = gfs2_file_dealloc(ip);
563 		if (error)
564 			goto out_iput;
565 	}
566 
567 	error = dinode_dealloc(ip, ul);
568 	if (error)
569 		goto out_iput;
570 
571  out_iput:
572 	gfs2_glmutex_lock(i_gh.gh_gl);
573 	gfs2_inode_put(ip);
574 	gfs2_inode_destroy(ip);
575 	gfs2_glmutex_unlock(i_gh.gh_gl);
576 
577  out:
578 	gfs2_glock_dq_uninit(&i_gh);
579 
580 	return error;
581 }
582 
583 /**
584  * try_inode_dealloc - Try to deallocate an inode and all its blocks
585  * @sdp: the filesystem
586  *
587  * Returns: 0 on success, -errno on error, 1 on busy (inode open)
588  */
589 
590 static int try_inode_dealloc(struct gfs2_sbd *sdp, struct gfs2_unlinked *ul)
591 {
592 	struct gfs2_holder io_gh;
593 	int error = 0;
594 
595 	gfs2_try_toss_inode(sdp, &ul->ul_ut.ut_inum);
596 
597 	error = gfs2_glock_nq_num(sdp,
598 				  ul->ul_ut.ut_inum.no_addr, &gfs2_iopen_glops,
599 				  LM_ST_EXCLUSIVE, LM_FLAG_TRY_1CB, &io_gh);
600 	switch (error) {
601 	case 0:
602 		break;
603 	case GLR_TRYFAILED:
604 		return 1;
605 	default:
606 		return error;
607 	}
608 
609 	gfs2_glock_dq(&io_gh);
610 	error = inode_dealloc(sdp, ul, &io_gh);
611 	gfs2_holder_uninit(&io_gh);
612 
613 	return error;
614 }
615 
616 static int inode_dealloc_uninit(struct gfs2_sbd *sdp, struct gfs2_unlinked *ul)
617 {
618 	struct gfs2_rgrpd *rgd;
619 	struct gfs2_holder ri_gh, rgd_gh;
620 	int error;
621 
622 	error = gfs2_rindex_hold(sdp, &ri_gh);
623 	if (error)
624 		return error;
625 
626 	rgd = gfs2_blk2rgrpd(sdp, ul->ul_ut.ut_inum.no_addr);
627 	if (!rgd) {
628 		gfs2_consist(sdp);
629 		error = -EIO;
630 		goto out;
631 	}
632 
633 	error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, &rgd_gh);
634 	if (error)
635 		goto out;
636 
637 	error = gfs2_trans_begin(sdp,
638 				 RES_RG_BIT + RES_UNLINKED + RES_STATFS,
639 				 0);
640 	if (error)
641 		goto out_gunlock;
642 
643 	gfs2_free_uninit_di(rgd, ul->ul_ut.ut_inum.no_addr);
644 	gfs2_unlinked_ondisk_rm(sdp, ul);
645 
646 	gfs2_trans_end(sdp);
647 
648  out_gunlock:
649 	gfs2_glock_dq_uninit(&rgd_gh);
650  out:
651 	gfs2_glock_dq_uninit(&ri_gh);
652 
653 	return error;
654 }
655 
656 int gfs2_inode_dealloc(struct gfs2_sbd *sdp, struct gfs2_unlinked *ul)
657 {
658 	if (ul->ul_ut.ut_flags & GFS2_UTF_UNINIT)
659 		return inode_dealloc_uninit(sdp, ul);
660 	else
661 		return try_inode_dealloc(sdp, ul);
662 }
663 
664 /**
665  * gfs2_change_nlink - Change nlink count on inode
666  * @ip: The GFS2 inode
667  * @diff: The change in the nlink count required
668  *
669  * Returns: errno
670  */
671 
672 int gfs2_change_nlink(struct gfs2_inode *ip, int diff)
673 {
674 	struct buffer_head *dibh;
675 	uint32_t nlink;
676 	int error;
677 
678 	nlink = ip->i_di.di_nlink + diff;
679 
680 	/* If we are reducing the nlink count, but the new value ends up being
681 	   bigger than the old one, we must have underflowed. */
682 	if (diff < 0 && nlink > ip->i_di.di_nlink) {
683 		if (gfs2_consist_inode(ip))
684 			gfs2_dinode_print(&ip->i_di);
685 		return -EIO;
686 	}
687 
688 	error = gfs2_meta_inode_buffer(ip, &dibh);
689 	if (error)
690 		return error;
691 
692 	ip->i_di.di_nlink = nlink;
693 	ip->i_di.di_ctime = get_seconds();
694 
695 	gfs2_trans_add_bh(ip->i_gl, dibh, 1);
696 	gfs2_dinode_out(&ip->i_di, dibh->b_data);
697 	brelse(dibh);
698 
699 	return 0;
700 }
701 
702 struct inode *gfs2_lookup_simple(struct inode *dip, const char *name)
703 {
704 	struct qstr qstr;
705 	gfs2_str2qstr(&qstr, name);
706 	return gfs2_lookupi(dip, &qstr, 1, NULL);
707 }
708 
709 
710 /**
711  * gfs2_lookupi - Look up a filename in a directory and return its inode
712  * @d_gh: An initialized holder for the directory glock
713  * @name: The name of the inode to look for
714  * @is_root: If 1, ignore the caller's permissions
715  * @i_gh: An uninitialized holder for the new inode glock
716  *
717  * There will always be a vnode (Linux VFS inode) for the d_gh inode unless
718  * @is_root is true.
719  *
720  * Returns: errno
721  */
722 
723 struct inode *gfs2_lookupi(struct inode *dir, struct qstr *name, int is_root,
724 			   struct nameidata *nd)
725 
726 {
727 	struct super_block *sb = dir->i_sb;
728 	struct gfs2_inode *ipp;
729 	struct gfs2_inode *dip = dir->u.generic_ip;
730 	struct gfs2_sbd *sdp = dip->i_sbd;
731 	struct gfs2_holder d_gh;
732 	struct gfs2_inum inum;
733 	unsigned int type;
734 	struct gfs2_glock *gl;
735 	int error = 0;
736 	struct inode *inode = NULL;
737 
738 	if (!name->len || name->len > GFS2_FNAMESIZE)
739 		return ERR_PTR(-ENAMETOOLONG);
740 
741 	if ((name->len == 1 && memcmp(name->name, ".", 1) == 0) ||
742 	    (name->len == 2 && memcmp(name->name, "..", 2) == 0 &&
743 	     dir == sb->s_root->d_inode)) {
744 		gfs2_inode_hold(dip);
745 		ipp = dip;
746 		goto done;
747 	}
748 
749 	error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh);
750 	if (error)
751 		return ERR_PTR(error);
752 
753 	if (!is_root) {
754 		error = gfs2_repermission(dip->i_vnode, MAY_EXEC, NULL);
755 		if (error)
756 			goto out;
757 	}
758 
759 	error = gfs2_dir_search(dir, name, &inum, &type);
760 	if (error)
761 		goto out;
762 
763 	error = gfs2_glock_get(sdp, inum.no_addr, &gfs2_inode_glops,
764 			       CREATE, &gl);
765 	if (error)
766 		goto out;
767 
768 	error = gfs2_inode_get(gl, &inum, CREATE, &ipp);
769 	if (!error)
770 		gfs2_inode_min_init(ipp, type);
771 
772 	gfs2_glock_put(gl);
773 
774 out:
775 	gfs2_glock_dq_uninit(&d_gh);
776 done:
777 	if (error == -ENOENT)
778 		return NULL;
779 	if (error == 0) {
780 		inode = gfs2_ip2v(ipp);
781 		gfs2_inode_put(ipp);
782 		if (!inode)
783 			return ERR_PTR(-ENOMEM);
784 		return inode;
785 	}
786 	return ERR_PTR(error);
787 }
788 
789 static int pick_formal_ino_1(struct gfs2_sbd *sdp, uint64_t *formal_ino)
790 {
791 	struct gfs2_inode *ip = sdp->sd_ir_inode->u.generic_ip;
792 	struct buffer_head *bh;
793 	struct gfs2_inum_range ir;
794 	int error;
795 
796 	error = gfs2_trans_begin(sdp, RES_DINODE, 0);
797 	if (error)
798 		return error;
799 	mutex_lock(&sdp->sd_inum_mutex);
800 
801 	error = gfs2_meta_inode_buffer(ip, &bh);
802 	if (error) {
803 		mutex_unlock(&sdp->sd_inum_mutex);
804 		gfs2_trans_end(sdp);
805 		return error;
806 	}
807 
808 	gfs2_inum_range_in(&ir, bh->b_data + sizeof(struct gfs2_dinode));
809 
810 	if (ir.ir_length) {
811 		*formal_ino = ir.ir_start++;
812 		ir.ir_length--;
813 		gfs2_trans_add_bh(ip->i_gl, bh, 1);
814 		gfs2_inum_range_out(&ir,
815 				    bh->b_data + sizeof(struct gfs2_dinode));
816 		brelse(bh);
817 		mutex_unlock(&sdp->sd_inum_mutex);
818 		gfs2_trans_end(sdp);
819 		return 0;
820 	}
821 
822 	brelse(bh);
823 
824 	mutex_unlock(&sdp->sd_inum_mutex);
825 	gfs2_trans_end(sdp);
826 
827 	return 1;
828 }
829 
830 static int pick_formal_ino_2(struct gfs2_sbd *sdp, uint64_t *formal_ino)
831 {
832 	struct gfs2_inode *ip = sdp->sd_ir_inode->u.generic_ip;
833 	struct gfs2_inode *m_ip = sdp->sd_inum_inode->u.generic_ip;
834 	struct gfs2_holder gh;
835 	struct buffer_head *bh;
836 	struct gfs2_inum_range ir;
837 	int error;
838 
839 	error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
840 	if (error)
841 		return error;
842 
843 	error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
844 	if (error)
845 		goto out;
846 	mutex_lock(&sdp->sd_inum_mutex);
847 
848 	error = gfs2_meta_inode_buffer(ip, &bh);
849 	if (error)
850 		goto out_end_trans;
851 
852 	gfs2_inum_range_in(&ir, bh->b_data + sizeof(struct gfs2_dinode));
853 
854 	if (!ir.ir_length) {
855 		struct buffer_head *m_bh;
856 		uint64_t x, y;
857 
858 		error = gfs2_meta_inode_buffer(m_ip, &m_bh);
859 		if (error)
860 			goto out_brelse;
861 
862 		x = *(uint64_t *)(m_bh->b_data + sizeof(struct gfs2_dinode));
863 		x = y = be64_to_cpu(x);
864 		ir.ir_start = x;
865 		ir.ir_length = GFS2_INUM_QUANTUM;
866 		x += GFS2_INUM_QUANTUM;
867 		if (x < y)
868 			gfs2_consist_inode(m_ip);
869 		x = cpu_to_be64(x);
870 		gfs2_trans_add_bh(m_ip->i_gl, m_bh, 1);
871 		*(uint64_t *)(m_bh->b_data + sizeof(struct gfs2_dinode)) = x;
872 
873 		brelse(m_bh);
874 	}
875 
876 	*formal_ino = ir.ir_start++;
877 	ir.ir_length--;
878 
879 	gfs2_trans_add_bh(ip->i_gl, bh, 1);
880 	gfs2_inum_range_out(&ir, bh->b_data + sizeof(struct gfs2_dinode));
881 
882  out_brelse:
883 	brelse(bh);
884 
885  out_end_trans:
886 	mutex_unlock(&sdp->sd_inum_mutex);
887 	gfs2_trans_end(sdp);
888 
889  out:
890 	gfs2_glock_dq_uninit(&gh);
891 
892 	return error;
893 }
894 
895 static int pick_formal_ino(struct gfs2_sbd *sdp, uint64_t *inum)
896 {
897 	int error;
898 
899 	error = pick_formal_ino_1(sdp, inum);
900 	if (error <= 0)
901 		return error;
902 
903 	error = pick_formal_ino_2(sdp, inum);
904 
905 	return error;
906 }
907 
908 /**
909  * create_ok - OK to create a new on-disk inode here?
910  * @dip:  Directory in which dinode is to be created
911  * @name:  Name of new dinode
912  * @mode:
913  *
914  * Returns: errno
915  */
916 
917 static int create_ok(struct gfs2_inode *dip, struct qstr *name,
918 		     unsigned int mode)
919 {
920 	int error;
921 
922 	error = gfs2_repermission(dip->i_vnode, MAY_WRITE | MAY_EXEC, NULL);
923 	if (error)
924 		return error;
925 
926 	/*  Don't create entries in an unlinked directory  */
927 	if (!dip->i_di.di_nlink)
928 		return -EPERM;
929 
930 	error = gfs2_dir_search(dip->i_vnode, name, NULL, NULL);
931 	switch (error) {
932 	case -ENOENT:
933 		error = 0;
934 		break;
935 	case 0:
936 		return -EEXIST;
937 	default:
938 		return error;
939 	}
940 
941 	if (dip->i_di.di_entries == (uint32_t)-1)
942 		return -EFBIG;
943 	if (S_ISDIR(mode) && dip->i_di.di_nlink == (uint32_t)-1)
944 		return -EMLINK;
945 
946 	return 0;
947 }
948 
949 static void munge_mode_uid_gid(struct gfs2_inode *dip, unsigned int *mode,
950 			       unsigned int *uid, unsigned int *gid)
951 {
952 	if (dip->i_sbd->sd_args.ar_suiddir &&
953 	    (dip->i_di.di_mode & S_ISUID) &&
954 	    dip->i_di.di_uid) {
955 		if (S_ISDIR(*mode))
956 			*mode |= S_ISUID;
957 		else if (dip->i_di.di_uid != current->fsuid)
958 			*mode &= ~07111;
959 		*uid = dip->i_di.di_uid;
960 	} else
961 		*uid = current->fsuid;
962 
963 	if (dip->i_di.di_mode & S_ISGID) {
964 		if (S_ISDIR(*mode))
965 			*mode |= S_ISGID;
966 		*gid = dip->i_di.di_gid;
967 	} else
968 		*gid = current->fsgid;
969 }
970 
971 static int alloc_dinode(struct gfs2_inode *dip, struct gfs2_unlinked *ul)
972 {
973 	struct gfs2_sbd *sdp = dip->i_sbd;
974 	int error;
975 
976 	gfs2_alloc_get(dip);
977 
978 	dip->i_alloc.al_requested = RES_DINODE;
979 	error = gfs2_inplace_reserve(dip);
980 	if (error)
981 		goto out;
982 
983 	error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_UNLINKED +
984 				 RES_STATFS, 0);
985 	if (error)
986 		goto out_ipreserv;
987 
988 	ul->ul_ut.ut_inum.no_addr = gfs2_alloc_di(dip);
989 
990 	ul->ul_ut.ut_flags = GFS2_UTF_UNINIT;
991 	error = gfs2_unlinked_ondisk_add(sdp, ul);
992 
993 	gfs2_trans_end(sdp);
994 
995  out_ipreserv:
996 	gfs2_inplace_release(dip);
997 
998  out:
999 	gfs2_alloc_put(dip);
1000 
1001 	return error;
1002 }
1003 
1004 /**
1005  * init_dinode - Fill in a new dinode structure
1006  * @dip: the directory this inode is being created in
1007  * @gl: The glock covering the new inode
1008  * @inum: the inode number
1009  * @mode: the file permissions
1010  * @uid:
1011  * @gid:
1012  *
1013  */
1014 
1015 static void init_dinode(struct gfs2_inode *dip, struct gfs2_glock *gl,
1016 			struct gfs2_inum *inum, unsigned int mode,
1017 			unsigned int uid, unsigned int gid)
1018 {
1019 	struct gfs2_sbd *sdp = dip->i_sbd;
1020 	struct gfs2_dinode *di;
1021 	struct buffer_head *dibh;
1022 
1023 	dibh = gfs2_meta_new(gl, inum->no_addr);
1024 	gfs2_trans_add_bh(gl, dibh, 1);
1025 	gfs2_metatype_set(dibh, GFS2_METATYPE_DI, GFS2_FORMAT_DI);
1026 	gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
1027 	di = (struct gfs2_dinode *)dibh->b_data;
1028 
1029 	di->di_num.no_formal_ino = cpu_to_be64(inum->no_formal_ino);
1030 	di->di_num.no_addr = cpu_to_be64(inum->no_addr);
1031 	di->di_mode = cpu_to_be32(mode);
1032 	di->di_uid = cpu_to_be32(uid);
1033 	di->di_gid = cpu_to_be32(gid);
1034 	di->di_nlink = cpu_to_be32(0);
1035 	di->di_size = cpu_to_be64(0);
1036 	di->di_blocks = cpu_to_be64(1);
1037 	di->di_atime = di->di_mtime = di->di_ctime = cpu_to_be64(get_seconds());
1038 	di->di_major = di->di_minor = cpu_to_be32(0);
1039 	di->di_goal_meta = di->di_goal_data = cpu_to_be64(inum->no_addr);
1040 	di->__pad[0] = di->__pad[1] = 0;
1041 	di->di_flags = cpu_to_be32(0);
1042 
1043 	if (S_ISREG(mode)) {
1044 		if ((dip->i_di.di_flags & GFS2_DIF_INHERIT_JDATA) ||
1045 		    gfs2_tune_get(sdp, gt_new_files_jdata))
1046 			di->di_flags |= cpu_to_be32(GFS2_DIF_JDATA);
1047 		if ((dip->i_di.di_flags & GFS2_DIF_INHERIT_DIRECTIO) ||
1048 		    gfs2_tune_get(sdp, gt_new_files_directio))
1049 			di->di_flags |= cpu_to_be32(GFS2_DIF_DIRECTIO);
1050 	} else if (S_ISDIR(mode)) {
1051 		di->di_flags |= cpu_to_be32(dip->i_di.di_flags &
1052 					    GFS2_DIF_INHERIT_DIRECTIO);
1053 		di->di_flags |= cpu_to_be32(dip->i_di.di_flags &
1054 					    GFS2_DIF_INHERIT_JDATA);
1055 	}
1056 
1057 	di->__pad1 = 0;
1058 	di->di_height = cpu_to_be32(0);
1059 	di->__pad2 = 0;
1060 	di->__pad3 = 0;
1061 	di->di_depth = cpu_to_be16(0);
1062 	di->di_entries = cpu_to_be32(0);
1063 	memset(&di->__pad4, 0, sizeof(di->__pad4));
1064 	di->di_eattr = cpu_to_be64(0);
1065 	memset(&di->di_reserved, 0, sizeof(di->di_reserved));
1066 
1067 	brelse(dibh);
1068 }
1069 
1070 static int make_dinode(struct gfs2_inode *dip, struct gfs2_glock *gl,
1071 		       unsigned int mode, struct gfs2_unlinked *ul)
1072 {
1073 	struct gfs2_sbd *sdp = dip->i_sbd;
1074 	unsigned int uid, gid;
1075 	int error;
1076 
1077 	munge_mode_uid_gid(dip, &mode, &uid, &gid);
1078 
1079 	gfs2_alloc_get(dip);
1080 
1081 	error = gfs2_quota_lock(dip, uid, gid);
1082 	if (error)
1083 		goto out;
1084 
1085 	error = gfs2_quota_check(dip, uid, gid);
1086 	if (error)
1087 		goto out_quota;
1088 
1089 	error = gfs2_trans_begin(sdp, RES_DINODE + RES_UNLINKED +
1090 				 RES_QUOTA, 0);
1091 	if (error)
1092 		goto out_quota;
1093 
1094 	ul->ul_ut.ut_flags = 0;
1095 	error = gfs2_unlinked_ondisk_munge(sdp, ul);
1096 
1097 	init_dinode(dip, gl, &ul->ul_ut.ut_inum,
1098 		     mode, uid, gid);
1099 
1100 	gfs2_quota_change(dip, +1, uid, gid);
1101 
1102 	gfs2_trans_end(sdp);
1103 
1104  out_quota:
1105 	gfs2_quota_unlock(dip);
1106 
1107  out:
1108 	gfs2_alloc_put(dip);
1109 
1110 	return error;
1111 }
1112 
1113 static int link_dinode(struct gfs2_inode *dip, struct qstr *name,
1114 		       struct gfs2_inode *ip, struct gfs2_unlinked *ul)
1115 {
1116 	struct gfs2_sbd *sdp = dip->i_sbd;
1117 	struct gfs2_alloc *al;
1118 	int alloc_required;
1119 	struct buffer_head *dibh;
1120 	int error;
1121 
1122 	al = gfs2_alloc_get(dip);
1123 
1124 	error = gfs2_quota_lock(dip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
1125 	if (error)
1126 		goto fail;
1127 
1128 	error = alloc_required = gfs2_diradd_alloc_required(dip->i_vnode, name);
1129 	if (alloc_required < 0)
1130 		goto fail;
1131 	if (alloc_required) {
1132 		error = gfs2_quota_check(dip, dip->i_di.di_uid,
1133 					 dip->i_di.di_gid);
1134 		if (error)
1135 			goto fail_quota_locks;
1136 
1137 		al->al_requested = sdp->sd_max_dirres;
1138 
1139 		error = gfs2_inplace_reserve(dip);
1140 		if (error)
1141 			goto fail_quota_locks;
1142 
1143 		error = gfs2_trans_begin(sdp,
1144 					 sdp->sd_max_dirres +
1145 					 al->al_rgd->rd_ri.ri_length +
1146 					 2 * RES_DINODE + RES_UNLINKED +
1147 					 RES_STATFS + RES_QUOTA, 0);
1148 		if (error)
1149 			goto fail_ipreserv;
1150 	} else {
1151 		error = gfs2_trans_begin(sdp,
1152 					 RES_LEAF +
1153 					 2 * RES_DINODE +
1154 					 RES_UNLINKED, 0);
1155 		if (error)
1156 			goto fail_quota_locks;
1157 	}
1158 
1159 	error = gfs2_dir_add(dip->i_vnode, name, &ip->i_num, IF2DT(ip->i_di.di_mode));
1160 	if (error)
1161 		goto fail_end_trans;
1162 
1163 	error = gfs2_meta_inode_buffer(ip, &dibh);
1164 	if (error)
1165 		goto fail_end_trans;
1166 	ip->i_di.di_nlink = 1;
1167 	gfs2_trans_add_bh(ip->i_gl, dibh, 1);
1168 	gfs2_dinode_out(&ip->i_di, dibh->b_data);
1169 	brelse(dibh);
1170 
1171 	error = gfs2_unlinked_ondisk_rm(sdp, ul);
1172 	if (error)
1173 		goto fail_end_trans;
1174 
1175 	return 0;
1176 
1177  fail_end_trans:
1178 	gfs2_trans_end(sdp);
1179 
1180  fail_ipreserv:
1181 	if (dip->i_alloc.al_rgd)
1182 		gfs2_inplace_release(dip);
1183 
1184  fail_quota_locks:
1185 	gfs2_quota_unlock(dip);
1186 
1187  fail:
1188 	gfs2_alloc_put(dip);
1189 
1190 	return error;
1191 }
1192 
1193 /**
1194  * gfs2_createi - Create a new inode
1195  * @ghs: An array of two holders
1196  * @name: The name of the new file
1197  * @mode: the permissions on the new inode
1198  *
1199  * @ghs[0] is an initialized holder for the directory
1200  * @ghs[1] is the holder for the inode lock
1201  *
1202  * If the return value is not NULL, the glocks on both the directory and the new
1203  * file are held.  A transaction has been started and an inplace reservation
1204  * is held, as well.
1205  *
1206  * Returns: An inode
1207  */
1208 
1209 struct inode *gfs2_createi(struct gfs2_holder *ghs, struct qstr *name,
1210 			   unsigned int mode)
1211 {
1212 	struct inode *inode;
1213 	struct gfs2_inode *dip = ghs->gh_gl->gl_object;
1214 	struct gfs2_sbd *sdp = dip->i_sbd;
1215 	struct gfs2_unlinked *ul;
1216 	struct gfs2_inode *ip;
1217 	int error;
1218 
1219 	if (!name->len || name->len > GFS2_FNAMESIZE)
1220 		return ERR_PTR(-ENAMETOOLONG);
1221 
1222 	error = gfs2_unlinked_get(sdp, &ul);
1223 	if (error)
1224 		return ERR_PTR(error);
1225 
1226 	gfs2_holder_reinit(LM_ST_EXCLUSIVE, 0, ghs);
1227 	error = gfs2_glock_nq(ghs);
1228 	if (error)
1229 		goto fail;
1230 
1231 	error = create_ok(dip, name, mode);
1232 	if (error)
1233 		goto fail_gunlock;
1234 
1235 	error = pick_formal_ino(sdp, &ul->ul_ut.ut_inum.no_formal_ino);
1236 	if (error)
1237 		goto fail_gunlock;
1238 
1239 	error = alloc_dinode(dip, ul);
1240 	if (error)
1241 		goto fail_gunlock;
1242 
1243 	if (ul->ul_ut.ut_inum.no_addr < dip->i_num.no_addr) {
1244 		gfs2_glock_dq(ghs);
1245 
1246 		error = gfs2_glock_nq_num(sdp,
1247 					  ul->ul_ut.ut_inum.no_addr,
1248 					  &gfs2_inode_glops,
1249 					  LM_ST_EXCLUSIVE, GL_SKIP,
1250 					  ghs + 1);
1251 		if (error) {
1252 			gfs2_unlinked_put(sdp, ul);
1253 			return ERR_PTR(error);
1254 		}
1255 
1256 		gfs2_holder_reinit(LM_ST_EXCLUSIVE, 0, ghs);
1257 		error = gfs2_glock_nq(ghs);
1258 		if (error) {
1259 			gfs2_glock_dq_uninit(ghs + 1);
1260 			gfs2_unlinked_put(sdp, ul);
1261 			return ERR_PTR(error);
1262 		}
1263 
1264 		error = create_ok(dip, name, mode);
1265 		if (error)
1266 			goto fail_gunlock2;
1267 	} else {
1268 		error = gfs2_glock_nq_num(sdp,
1269 					  ul->ul_ut.ut_inum.no_addr,
1270 					  &gfs2_inode_glops,
1271 					  LM_ST_EXCLUSIVE, GL_SKIP,
1272 					  ghs + 1);
1273 		if (error)
1274 			goto fail_gunlock;
1275 	}
1276 
1277 	error = make_dinode(dip, ghs[1].gh_gl, mode, ul);
1278 	if (error)
1279 		goto fail_gunlock2;
1280 
1281 	error = gfs2_inode_get(ghs[1].gh_gl, &ul->ul_ut.ut_inum, CREATE, &ip);
1282 	if (error)
1283 		goto fail_gunlock2;
1284 
1285 	error = gfs2_inode_refresh(ip);
1286 	if (error)
1287 		goto fail_iput;
1288 
1289 	error = gfs2_acl_create(dip, ip);
1290 	if (error)
1291 		goto fail_iput;
1292 
1293 	error = link_dinode(dip, name, ip, ul);
1294 	if (error)
1295 		goto fail_iput;
1296 
1297 	gfs2_unlinked_put(sdp, ul);
1298 
1299 	inode = gfs2_ip2v(ip);
1300 	gfs2_inode_put(ip);
1301 	if (!inode)
1302 		return ERR_PTR(-ENOMEM);
1303 	return inode;
1304 
1305  fail_iput:
1306 	gfs2_inode_put(ip);
1307 
1308  fail_gunlock2:
1309 	gfs2_glock_dq_uninit(ghs + 1);
1310 
1311  fail_gunlock:
1312 	gfs2_glock_dq(ghs);
1313 
1314  fail:
1315 	gfs2_unlinked_put(sdp, ul);
1316 
1317 	return ERR_PTR(error);
1318 }
1319 
1320 /**
1321  * gfs2_unlinki - Unlink a file
1322  * @dip: The inode of the directory
1323  * @name: The name of the file to be unlinked
1324  * @ip: The inode of the file to be removed
1325  *
1326  * Assumes Glocks on both dip and ip are held.
1327  *
1328  * Returns: errno
1329  */
1330 
1331 int gfs2_unlinki(struct gfs2_inode *dip, struct qstr *name,
1332 		 struct gfs2_inode *ip, struct gfs2_unlinked *ul)
1333 {
1334 	struct gfs2_sbd *sdp = dip->i_sbd;
1335 	int error;
1336 
1337 	error = gfs2_dir_del(dip, name);
1338 	if (error)
1339 		return error;
1340 
1341 	error = gfs2_change_nlink(ip, -1);
1342 	if (error)
1343 		return error;
1344 
1345 	/* If this inode is being unlinked from the directory structure,
1346 	   we need to mark that in the log so that it isn't lost during
1347 	   a crash. */
1348 
1349 	if (!ip->i_di.di_nlink) {
1350 		ul->ul_ut.ut_inum = ip->i_num;
1351 		error = gfs2_unlinked_ondisk_add(sdp, ul);
1352 		if (!error)
1353 			set_bit(GLF_STICKY, &ip->i_gl->gl_flags);
1354 	}
1355 
1356 	return error;
1357 }
1358 
1359 /**
1360  * gfs2_rmdiri - Remove a directory
1361  * @dip: The parent directory of the directory to be removed
1362  * @name: The name of the directory to be removed
1363  * @ip: The GFS2 inode of the directory to be removed
1364  *
1365  * Assumes Glocks on dip and ip are held
1366  *
1367  * Returns: errno
1368  */
1369 
1370 int gfs2_rmdiri(struct gfs2_inode *dip, struct qstr *name,
1371 		struct gfs2_inode *ip, struct gfs2_unlinked *ul)
1372 {
1373 	struct gfs2_sbd *sdp = dip->i_sbd;
1374 	struct qstr dotname;
1375 	int error;
1376 
1377 	if (ip->i_di.di_entries != 2) {
1378 		if (gfs2_consist_inode(ip))
1379 			gfs2_dinode_print(&ip->i_di);
1380 		return -EIO;
1381 	}
1382 
1383 	error = gfs2_dir_del(dip, name);
1384 	if (error)
1385 		return error;
1386 
1387 	error = gfs2_change_nlink(dip, -1);
1388 	if (error)
1389 		return error;
1390 
1391 	gfs2_str2qstr(&dotname, ".");
1392 	error = gfs2_dir_del(ip, &dotname);
1393 	if (error)
1394 		return error;
1395 
1396 	dotname.len = 2;
1397 	dotname.name = "..";
1398 	dotname.hash = gfs2_disk_hash(dotname.name, dotname.len);
1399 	error = gfs2_dir_del(ip, &dotname);
1400 	if (error)
1401 		return error;
1402 
1403 	error = gfs2_change_nlink(ip, -2);
1404 	if (error)
1405 		return error;
1406 
1407 	/* This inode is being unlinked from the directory structure and
1408 	   we need to mark that in the log so that it isn't lost during
1409 	   a crash. */
1410 
1411 	ul->ul_ut.ut_inum = ip->i_num;
1412 	error = gfs2_unlinked_ondisk_add(sdp, ul);
1413 	if (!error)
1414 		set_bit(GLF_STICKY, &ip->i_gl->gl_flags);
1415 
1416 	return error;
1417 }
1418 
1419 /*
1420  * gfs2_unlink_ok - check to see that a inode is still in a directory
1421  * @dip: the directory
1422  * @name: the name of the file
1423  * @ip: the inode
1424  *
1425  * Assumes that the lock on (at least) @dip is held.
1426  *
1427  * Returns: 0 if the parent/child relationship is correct, errno if it isn't
1428  */
1429 
1430 int gfs2_unlink_ok(struct gfs2_inode *dip, struct qstr *name,
1431 		   struct gfs2_inode *ip)
1432 {
1433 	struct gfs2_inum inum;
1434 	unsigned int type;
1435 	int error;
1436 
1437 	if (IS_IMMUTABLE(ip->i_vnode) || IS_APPEND(ip->i_vnode))
1438 		return -EPERM;
1439 
1440 	if ((dip->i_di.di_mode & S_ISVTX) &&
1441 	    dip->i_di.di_uid != current->fsuid &&
1442 	    ip->i_di.di_uid != current->fsuid &&
1443 	    !capable(CAP_FOWNER))
1444 		return -EPERM;
1445 
1446 	if (IS_APPEND(dip->i_vnode))
1447 		return -EPERM;
1448 
1449 	error = gfs2_repermission(dip->i_vnode, MAY_WRITE | MAY_EXEC, NULL);
1450 	if (error)
1451 		return error;
1452 
1453 	error = gfs2_dir_search(dip->i_vnode, name, &inum, &type);
1454 	if (error)
1455 		return error;
1456 
1457 	if (!gfs2_inum_equal(&inum, &ip->i_num))
1458 		return -ENOENT;
1459 
1460 	if (IF2DT(ip->i_di.di_mode) != type) {
1461 		gfs2_consist_inode(dip);
1462 		return -EIO;
1463 	}
1464 
1465 	return 0;
1466 }
1467 
1468 /*
1469  * gfs2_ok_to_move - check if it's ok to move a directory to another directory
1470  * @this: move this
1471  * @to: to here
1472  *
1473  * Follow @to back to the root and make sure we don't encounter @this
1474  * Assumes we already hold the rename lock.
1475  *
1476  * Returns: errno
1477  */
1478 
1479 int gfs2_ok_to_move(struct gfs2_inode *this, struct gfs2_inode *to)
1480 {
1481 	struct inode *dir = to->i_vnode;
1482 	struct super_block *sb = dir->i_sb;
1483 	struct inode *tmp;
1484 	struct qstr dotdot;
1485 	int error = 0;
1486 
1487 	gfs2_str2qstr(&dotdot, "..");
1488 
1489 	igrab(dir);
1490 
1491 	for (;;) {
1492 		if (dir == this->i_vnode) {
1493 			error = -EINVAL;
1494 			break;
1495 		}
1496 		if (dir == sb->s_root->d_inode) {
1497 			error = 0;
1498 			break;
1499 		}
1500 
1501 		tmp = gfs2_lookupi(dir, &dotdot, 1, NULL);
1502 		if (IS_ERR(tmp)) {
1503 			error = PTR_ERR(tmp);
1504 			break;
1505 		}
1506 
1507 		iput(dir);
1508 		dir = tmp;
1509 	}
1510 
1511 	iput(dir);
1512 
1513 	return error;
1514 }
1515 
1516 /**
1517  * gfs2_readlinki - return the contents of a symlink
1518  * @ip: the symlink's inode
1519  * @buf: a pointer to the buffer to be filled
1520  * @len: a pointer to the length of @buf
1521  *
1522  * If @buf is too small, a piece of memory is kmalloc()ed and needs
1523  * to be freed by the caller.
1524  *
1525  * Returns: errno
1526  */
1527 
1528 int gfs2_readlinki(struct gfs2_inode *ip, char **buf, unsigned int *len)
1529 {
1530 	struct gfs2_holder i_gh;
1531 	struct buffer_head *dibh;
1532 	unsigned int x;
1533 	int error;
1534 
1535 	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &i_gh);
1536 	error = gfs2_glock_nq_atime(&i_gh);
1537 	if (error) {
1538 		gfs2_holder_uninit(&i_gh);
1539 		return error;
1540 	}
1541 
1542 	if (!ip->i_di.di_size) {
1543 		gfs2_consist_inode(ip);
1544 		error = -EIO;
1545 		goto out;
1546 	}
1547 
1548 	error = gfs2_meta_inode_buffer(ip, &dibh);
1549 	if (error)
1550 		goto out;
1551 
1552 	x = ip->i_di.di_size + 1;
1553 	if (x > *len) {
1554 		*buf = kmalloc(x, GFP_KERNEL);
1555 		if (!*buf) {
1556 			error = -ENOMEM;
1557 			goto out_brelse;
1558 		}
1559 	}
1560 
1561 	memcpy(*buf, dibh->b_data + sizeof(struct gfs2_dinode), x);
1562 	*len = x;
1563 
1564  out_brelse:
1565 	brelse(dibh);
1566 
1567  out:
1568 	gfs2_glock_dq_uninit(&i_gh);
1569 
1570 	return error;
1571 }
1572 
1573 /**
1574  * gfs2_glock_nq_atime - Acquire a hold on an inode's glock, and
1575  *       conditionally update the inode's atime
1576  * @gh: the holder to acquire
1577  *
1578  * Tests atime (access time) for gfs2_read, gfs2_readdir and gfs2_mmap
1579  * Update if the difference between the current time and the inode's current
1580  * atime is greater than an interval specified at mount.
1581  *
1582  * Returns: errno
1583  */
1584 
1585 int gfs2_glock_nq_atime(struct gfs2_holder *gh)
1586 {
1587 	struct gfs2_glock *gl = gh->gh_gl;
1588 	struct gfs2_sbd *sdp = gl->gl_sbd;
1589 	struct gfs2_inode *ip = gl->gl_object;
1590 	int64_t curtime, quantum = gfs2_tune_get(sdp, gt_atime_quantum);
1591 	unsigned int state;
1592 	int flags;
1593 	int error;
1594 
1595 	if (gfs2_assert_warn(sdp, gh->gh_flags & GL_ATIME) ||
1596 	    gfs2_assert_warn(sdp, !(gh->gh_flags & GL_ASYNC)) ||
1597 	    gfs2_assert_warn(sdp, gl->gl_ops == &gfs2_inode_glops))
1598 		return -EINVAL;
1599 
1600 	state = gh->gh_state;
1601 	flags = gh->gh_flags;
1602 
1603 	error = gfs2_glock_nq(gh);
1604 	if (error)
1605 		return error;
1606 
1607 	if (test_bit(SDF_NOATIME, &sdp->sd_flags) ||
1608 	    (sdp->sd_vfs->s_flags & MS_RDONLY))
1609 		return 0;
1610 
1611 	curtime = get_seconds();
1612 	if (curtime - ip->i_di.di_atime >= quantum) {
1613 		gfs2_glock_dq(gh);
1614 		gfs2_holder_reinit(LM_ST_EXCLUSIVE,
1615 				  gh->gh_flags & ~LM_FLAG_ANY,
1616 				  gh);
1617 		error = gfs2_glock_nq(gh);
1618 		if (error)
1619 			return error;
1620 
1621 		/* Verify that atime hasn't been updated while we were
1622 		   trying to get exclusive lock. */
1623 
1624 		curtime = get_seconds();
1625 		if (curtime - ip->i_di.di_atime >= quantum) {
1626 			struct buffer_head *dibh;
1627 
1628 			error = gfs2_trans_begin(sdp, RES_DINODE, 0);
1629 			if (error == -EROFS)
1630 				return 0;
1631 			if (error)
1632 				goto fail;
1633 
1634 			error = gfs2_meta_inode_buffer(ip, &dibh);
1635 			if (error)
1636 				goto fail_end_trans;
1637 
1638 			ip->i_di.di_atime = curtime;
1639 
1640 			gfs2_trans_add_bh(ip->i_gl, dibh, 1);
1641 			gfs2_dinode_out(&ip->i_di, dibh->b_data);
1642 			brelse(dibh);
1643 
1644 			gfs2_trans_end(sdp);
1645 		}
1646 
1647 		/* If someone else has asked for the glock,
1648 		   unlock and let them have it. Then reacquire
1649 		   in the original state. */
1650 		if (gfs2_glock_is_blocking(gl)) {
1651 			gfs2_glock_dq(gh);
1652 			gfs2_holder_reinit(state, flags, gh);
1653 			return gfs2_glock_nq(gh);
1654 		}
1655 	}
1656 
1657 	return 0;
1658 
1659  fail_end_trans:
1660 	gfs2_trans_end(sdp);
1661 
1662  fail:
1663 	gfs2_glock_dq(gh);
1664 
1665 	return error;
1666 }
1667 
1668 /**
1669  * glock_compare_atime - Compare two struct gfs2_glock structures for sort
1670  * @arg_a: the first structure
1671  * @arg_b: the second structure
1672  *
1673  * Returns: 1 if A > B
1674  *         -1 if A < B
1675  *          0 if A = B
1676  */
1677 
1678 static int glock_compare_atime(const void *arg_a, const void *arg_b)
1679 {
1680 	struct gfs2_holder *gh_a = *(struct gfs2_holder **)arg_a;
1681 	struct gfs2_holder *gh_b = *(struct gfs2_holder **)arg_b;
1682 	struct lm_lockname *a = &gh_a->gh_gl->gl_name;
1683 	struct lm_lockname *b = &gh_b->gh_gl->gl_name;
1684 	int ret = 0;
1685 
1686 	if (a->ln_number > b->ln_number)
1687 		ret = 1;
1688 	else if (a->ln_number < b->ln_number)
1689 		ret = -1;
1690 	else {
1691 		if (gh_a->gh_state == LM_ST_SHARED &&
1692 		    gh_b->gh_state == LM_ST_EXCLUSIVE)
1693 			ret = 1;
1694 		else if (gh_a->gh_state == LM_ST_SHARED &&
1695 			 (gh_b->gh_flags & GL_ATIME))
1696 			ret = 1;
1697 	}
1698 
1699 	return ret;
1700 }
1701 
1702 /**
1703  * gfs2_glock_nq_m_atime - acquire multiple glocks where one may need an
1704  *      atime update
1705  * @num_gh: the number of structures
1706  * @ghs: an array of struct gfs2_holder structures
1707  *
1708  * Returns: 0 on success (all glocks acquired),
1709  *          errno on failure (no glocks acquired)
1710  */
1711 
1712 int gfs2_glock_nq_m_atime(unsigned int num_gh, struct gfs2_holder *ghs)
1713 {
1714 	struct gfs2_holder **p;
1715 	unsigned int x;
1716 	int error = 0;
1717 
1718 	if (!num_gh)
1719 		return 0;
1720 
1721 	if (num_gh == 1) {
1722 		ghs->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC);
1723 		if (ghs->gh_flags & GL_ATIME)
1724 			error = gfs2_glock_nq_atime(ghs);
1725 		else
1726 			error = gfs2_glock_nq(ghs);
1727 		return error;
1728 	}
1729 
1730 	p = kcalloc(num_gh, sizeof(struct gfs2_holder *), GFP_KERNEL);
1731 	if (!p)
1732 		return -ENOMEM;
1733 
1734 	for (x = 0; x < num_gh; x++)
1735 		p[x] = &ghs[x];
1736 
1737 	sort(p, num_gh, sizeof(struct gfs2_holder *), glock_compare_atime,NULL);
1738 
1739 	for (x = 0; x < num_gh; x++) {
1740 		p[x]->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC);
1741 
1742 		if (p[x]->gh_flags & GL_ATIME)
1743 			error = gfs2_glock_nq_atime(p[x]);
1744 		else
1745 			error = gfs2_glock_nq(p[x]);
1746 
1747 		if (error) {
1748 			while (x--)
1749 				gfs2_glock_dq(p[x]);
1750 			break;
1751 		}
1752 	}
1753 
1754 	kfree(p);
1755 
1756 	return error;
1757 }
1758 
1759 /**
1760  * gfs2_try_toss_vnode - See if we can toss a vnode from memory
1761  * @ip: the inode
1762  *
1763  * Returns:  1 if the vnode was tossed
1764  */
1765 
1766 void gfs2_try_toss_vnode(struct gfs2_inode *ip)
1767 {
1768 	struct inode *inode;
1769 
1770 	inode = gfs2_ip2v_lookup(ip);
1771 	if (!inode)
1772 		return;
1773 
1774 	d_prune_aliases(inode);
1775 
1776 	if (S_ISDIR(ip->i_di.di_mode)) {
1777 		struct list_head *head = &inode->i_dentry;
1778 		struct dentry *d = NULL;
1779 
1780 		spin_lock(&dcache_lock);
1781 		if (list_empty(head))
1782 			spin_unlock(&dcache_lock);
1783 		else {
1784 			d = list_entry(head->next, struct dentry, d_alias);
1785 			dget_locked(d);
1786 			spin_unlock(&dcache_lock);
1787 
1788 			if (have_submounts(d))
1789 				dput(d);
1790 			else {
1791 				shrink_dcache_parent(d);
1792 				dput(d);
1793 				d_prune_aliases(inode);
1794 			}
1795 		}
1796 	}
1797 
1798 	inode->i_nlink = 0;
1799 	iput(inode);
1800 }
1801 
1802 
1803 static int
1804 __gfs2_setattr_simple(struct gfs2_inode *ip, struct iattr *attr)
1805 {
1806 	struct buffer_head *dibh;
1807 	int error;
1808 
1809 	error = gfs2_meta_inode_buffer(ip, &dibh);
1810 	if (!error) {
1811 		error = inode_setattr(ip->i_vnode, attr);
1812 		gfs2_assert_warn(ip->i_sbd, !error);
1813 		gfs2_inode_attr_out(ip);
1814 
1815 		gfs2_trans_add_bh(ip->i_gl, dibh, 1);
1816 		gfs2_dinode_out(&ip->i_di, dibh->b_data);
1817 		brelse(dibh);
1818 	}
1819 	return error;
1820 }
1821 
1822 /**
1823  * gfs2_setattr_simple -
1824  * @ip:
1825  * @attr:
1826  *
1827  * Called with a reference on the vnode.
1828  *
1829  * Returns: errno
1830  */
1831 
1832 int gfs2_setattr_simple(struct gfs2_inode *ip, struct iattr *attr)
1833 {
1834 	int error;
1835 
1836 	if (current->journal_info)
1837 		return __gfs2_setattr_simple(ip, attr);
1838 
1839 	error = gfs2_trans_begin(ip->i_sbd, RES_DINODE, 0);
1840 	if (error)
1841 		return error;
1842 
1843 	error = __gfs2_setattr_simple(ip, attr);
1844 
1845 	gfs2_trans_end(ip->i_sbd);
1846 
1847 	return error;
1848 }
1849 
1850 int gfs2_repermission(struct inode *inode, int mask, struct nameidata *nd)
1851 {
1852 	return permission(inode, mask, nd);
1853 }
1854 
1855