xref: /openbmc/linux/fs/gfs2/inode.c (revision 36327521)
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, int need_lock)
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 	if (need_lock) {
316 		error = gfs2_glock_nq_init(io_gl,
317 					   io_state, GL_LOCAL_EXCL | GL_EXACT,
318 					   &ip->i_iopen_gh);
319 		if (error)
320 			goto fail;
321 	}
322 	ip->i_iopen_gh.gh_owner = NULL;
323 
324 	spin_lock(&io_gl->gl_spin);
325 	gfs2_glock_hold(i_gl);
326 	io_gl->gl_object = i_gl;
327 	spin_unlock(&io_gl->gl_spin);
328 
329 	gfs2_glock_hold(i_gl);
330 	i_gl->gl_object = ip;
331 
332 	atomic_inc(&sdp->sd_inode_count);
333 
334 	*ipp = ip;
335 
336 	return 0;
337 
338  fail:
339 	gfs2_meta_cache_flush(ip);
340 	kmem_cache_free(gfs2_inode_cachep, ip);
341 	*ipp = NULL;
342 
343 	return error;
344 }
345 
346 /**
347  * gfs2_inode_get - Create or get a reference on an inode
348  * @i_gl: The glock covering the inode
349  * @inum: The inode number
350  * @create:
351  * @ipp: pointer to put the returned inode in
352  *
353  * Returns: errno
354  */
355 
356 int gfs2_inode_get(struct gfs2_glock *i_gl, const struct gfs2_inum *inum,
357 		   int create, struct gfs2_inode **ipp)
358 {
359 	struct gfs2_sbd *sdp = i_gl->gl_sbd;
360 	struct gfs2_glock *io_gl;
361 	int error = 0;
362 
363 	gfs2_glmutex_lock(i_gl);
364 
365 	*ipp = i_gl->gl_object;
366 	if (*ipp) {
367 		error = -ESTALE;
368 		if ((*ipp)->i_num.no_formal_ino != inum->no_formal_ino)
369 			goto out;
370 		atomic_inc(&(*ipp)->i_count);
371 		error = 0;
372 		goto out;
373 	}
374 
375 	if (!create)
376 		goto out;
377 
378 	error = gfs2_glock_get(sdp, inum->no_addr, &gfs2_iopen_glops,
379 			       CREATE, &io_gl);
380 	if (!error) {
381 		error = inode_create(i_gl, inum, io_gl, LM_ST_SHARED, ipp, 1);
382 		gfs2_glock_put(io_gl);
383 	}
384 
385  out:
386 	gfs2_glmutex_unlock(i_gl);
387 
388 	return error;
389 }
390 
391 void gfs2_inode_hold(struct gfs2_inode *ip)
392 {
393 	gfs2_assert(ip->i_sbd, atomic_read(&ip->i_count) > 0);
394 	atomic_inc(&ip->i_count);
395 }
396 
397 void gfs2_inode_put(struct gfs2_inode *ip)
398 {
399 	gfs2_assert(ip->i_sbd, atomic_read(&ip->i_count) > 0);
400 	atomic_dec(&ip->i_count);
401 }
402 
403 void gfs2_inode_destroy(struct gfs2_inode *ip, int unlock)
404 {
405 	struct gfs2_sbd *sdp = ip->i_sbd;
406 	struct gfs2_glock *i_gl = ip->i_gl;
407 
408 	gfs2_assert_warn(sdp, !atomic_read(&ip->i_count));
409 	if (unlock) {
410 		struct gfs2_glock *io_gl = ip->i_iopen_gh.gh_gl;
411 		gfs2_assert(sdp, io_gl->gl_object == i_gl);
412 
413 		spin_lock(&io_gl->gl_spin);
414 		io_gl->gl_object = NULL;
415 		spin_unlock(&io_gl->gl_spin);
416 		gfs2_glock_put(i_gl);
417 
418 		gfs2_glock_dq_uninit(&ip->i_iopen_gh);
419 	}
420 
421 	gfs2_meta_cache_flush(ip);
422 	kmem_cache_free(gfs2_inode_cachep, ip);
423 
424 	i_gl->gl_object = NULL;
425 	gfs2_glock_put(i_gl);
426 
427 	atomic_dec(&sdp->sd_inode_count);
428 }
429 
430 static int dinode_dealloc(struct gfs2_inode *ip, struct gfs2_unlinked *ul)
431 {
432 	struct gfs2_sbd *sdp = ip->i_sbd;
433 	struct gfs2_alloc *al;
434 	struct gfs2_rgrpd *rgd;
435 	int error;
436 
437 	if (ip->i_di.di_blocks != 1) {
438 		if (gfs2_consist_inode(ip))
439 			gfs2_dinode_print(&ip->i_di);
440 		return -EIO;
441 	}
442 
443 	al = gfs2_alloc_get(ip);
444 
445 	error = gfs2_quota_hold(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
446 	if (error)
447 		goto out;
448 
449 	error = gfs2_rindex_hold(sdp, &al->al_ri_gh);
450 	if (error)
451 		goto out_qs;
452 
453 	rgd = gfs2_blk2rgrpd(sdp, ip->i_num.no_addr);
454 	if (!rgd) {
455 		gfs2_consist_inode(ip);
456 		error = -EIO;
457 		goto out_rindex_relse;
458 	}
459 
460 	error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0,
461 				   &al->al_rgd_gh);
462 	if (error)
463 		goto out_rindex_relse;
464 
465 	error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_UNLINKED +
466 				 RES_STATFS + RES_QUOTA, 1);
467 	if (error)
468 		goto out_rg_gunlock;
469 
470 	gfs2_trans_add_gl(ip->i_gl);
471 
472 	gfs2_free_di(rgd, ip);
473 
474 	error = gfs2_unlinked_ondisk_rm(sdp, ul);
475 
476 	gfs2_trans_end(sdp);
477 	clear_bit(GLF_STICKY, &ip->i_gl->gl_flags);
478 
479  out_rg_gunlock:
480 	gfs2_glock_dq_uninit(&al->al_rgd_gh);
481 
482  out_rindex_relse:
483 	gfs2_glock_dq_uninit(&al->al_ri_gh);
484 
485  out_qs:
486 	gfs2_quota_unhold(ip);
487 
488  out:
489 	gfs2_alloc_put(ip);
490 
491 	return error;
492 }
493 
494 /**
495  * inode_dealloc - Deallocate all on-disk blocks for an inode (dinode)
496  * @sdp: the filesystem
497  * @inum: the inode number to deallocate
498  * @io_gh: a holder for the iopen glock for this inode
499  *
500  * N.B. When we enter this we already hold the iopen glock and getting
501  * the glock for the inode means that we are grabbing the locks in the
502  * "wrong" order so we must only so a try lock operation and fail if we
503  * don't get the lock. Thats ok, since if we fail it means someone else
504  * is using the inode still and thus we shouldn't be deallocating it
505  * anyway.
506  *
507  * Returns: errno
508  */
509 
510 static int inode_dealloc(struct gfs2_sbd *sdp, struct gfs2_unlinked *ul,
511 			 struct gfs2_holder *io_gh)
512 {
513 	struct gfs2_inode *ip;
514 	struct gfs2_holder i_gh;
515 	int error;
516 
517 	error = gfs2_glock_nq_num(sdp, ul->ul_ut.ut_inum.no_addr,
518 				  &gfs2_inode_glops, LM_ST_EXCLUSIVE,
519 				  LM_FLAG_TRY_1CB, &i_gh);
520 	switch(error) {
521 	case 0:
522 		break;
523 	case GLR_TRYFAILED:
524 		return 1; /* or back off and relock in different order? */
525 	default:
526 		return error;
527 	}
528 
529 	gfs2_assert_warn(sdp, !i_gh.gh_gl->gl_object);
530 	error = inode_create(i_gh.gh_gl, &ul->ul_ut.ut_inum, io_gh->gh_gl,
531 			     LM_ST_EXCLUSIVE, &ip, 0);
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, 0);
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 	int error = 0;
592 	struct gfs2_holder iogh;
593 
594 	gfs2_try_toss_inode(sdp, &ul->ul_ut.ut_inum);
595 	error = gfs2_glock_nq_num(sdp, ul->ul_ut.ut_inum.no_addr,
596 				  &gfs2_iopen_glops, LM_ST_EXCLUSIVE,
597 				  LM_FLAG_TRY_1CB, &iogh);
598 	switch (error) {
599 	case 0:
600 		break;
601 	case GLR_TRYFAILED:
602 		return 1;
603 	default:
604 		return error;
605 	}
606 
607 	error = inode_dealloc(sdp, ul, &iogh);
608 	gfs2_glock_dq_uninit(&iogh);
609 
610 	return error;
611 }
612 
613 static int inode_dealloc_uninit(struct gfs2_sbd *sdp, struct gfs2_unlinked *ul)
614 {
615 	struct gfs2_rgrpd *rgd;
616 	struct gfs2_holder ri_gh, rgd_gh;
617 	int error;
618 
619 	error = gfs2_rindex_hold(sdp, &ri_gh);
620 	if (error)
621 		return error;
622 
623 	rgd = gfs2_blk2rgrpd(sdp, ul->ul_ut.ut_inum.no_addr);
624 	if (!rgd) {
625 		gfs2_consist(sdp);
626 		error = -EIO;
627 		goto out;
628 	}
629 
630 	error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, &rgd_gh);
631 	if (error)
632 		goto out;
633 
634 	error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_UNLINKED + RES_STATFS, 0);
635 	if (error)
636 		goto out_gunlock;
637 
638 	gfs2_free_uninit_di(rgd, ul->ul_ut.ut_inum.no_addr);
639 	gfs2_unlinked_ondisk_rm(sdp, ul);
640 
641 	gfs2_trans_end(sdp);
642 
643  out_gunlock:
644 	gfs2_glock_dq_uninit(&rgd_gh);
645  out:
646 	gfs2_glock_dq_uninit(&ri_gh);
647 
648 	return error;
649 }
650 
651 int gfs2_inode_dealloc(struct gfs2_sbd *sdp, struct gfs2_unlinked *ul)
652 {
653 	if (ul->ul_ut.ut_flags & GFS2_UTF_UNINIT)
654 		return inode_dealloc_uninit(sdp, ul);
655 	else
656 		return try_inode_dealloc(sdp, ul);
657 }
658 
659 /**
660  * gfs2_change_nlink - Change nlink count on inode
661  * @ip: The GFS2 inode
662  * @diff: The change in the nlink count required
663  *
664  * Returns: errno
665  */
666 
667 int gfs2_change_nlink(struct gfs2_inode *ip, int diff)
668 {
669 	struct buffer_head *dibh;
670 	uint32_t nlink;
671 	int error;
672 
673 	nlink = ip->i_di.di_nlink + diff;
674 
675 	/* If we are reducing the nlink count, but the new value ends up being
676 	   bigger than the old one, we must have underflowed. */
677 	if (diff < 0 && nlink > ip->i_di.di_nlink) {
678 		if (gfs2_consist_inode(ip))
679 			gfs2_dinode_print(&ip->i_di);
680 		return -EIO;
681 	}
682 
683 	error = gfs2_meta_inode_buffer(ip, &dibh);
684 	if (error)
685 		return error;
686 
687 	ip->i_di.di_nlink = nlink;
688 	ip->i_di.di_ctime = get_seconds();
689 
690 	gfs2_trans_add_bh(ip->i_gl, dibh, 1);
691 	gfs2_dinode_out(&ip->i_di, dibh->b_data);
692 	brelse(dibh);
693 
694 	return 0;
695 }
696 
697 struct inode *gfs2_lookup_simple(struct inode *dip, const char *name)
698 {
699 	struct qstr qstr;
700 	gfs2_str2qstr(&qstr, name);
701 	return gfs2_lookupi(dip, &qstr, 1, NULL);
702 }
703 
704 
705 /**
706  * gfs2_lookupi - Look up a filename in a directory and return its inode
707  * @d_gh: An initialized holder for the directory glock
708  * @name: The name of the inode to look for
709  * @is_root: If 1, ignore the caller's permissions
710  * @i_gh: An uninitialized holder for the new inode glock
711  *
712  * There will always be a vnode (Linux VFS inode) for the d_gh inode unless
713  * @is_root is true.
714  *
715  * Returns: errno
716  */
717 
718 struct inode *gfs2_lookupi(struct inode *dir, struct qstr *name, int is_root,
719 			   struct nameidata *nd)
720 
721 {
722 	struct super_block *sb = dir->i_sb;
723 	struct gfs2_inode *ipp;
724 	struct gfs2_inode *dip = dir->u.generic_ip;
725 	struct gfs2_sbd *sdp = dip->i_sbd;
726 	struct gfs2_holder d_gh;
727 	struct gfs2_inum inum;
728 	unsigned int type;
729 	struct gfs2_glock *gl;
730 	int error = 0;
731 	struct inode *inode = NULL;
732 
733 	if (!name->len || name->len > GFS2_FNAMESIZE)
734 		return ERR_PTR(-ENAMETOOLONG);
735 
736 	if ((name->len == 1 && memcmp(name->name, ".", 1) == 0) ||
737 	    (name->len == 2 && memcmp(name->name, "..", 2) == 0 &&
738 	     dir == sb->s_root->d_inode)) {
739 		gfs2_inode_hold(dip);
740 		ipp = dip;
741 		goto done;
742 	}
743 
744 	error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh);
745 	if (error)
746 		return ERR_PTR(error);
747 
748 	if (!is_root) {
749 		error = gfs2_repermission(dip->i_vnode, MAY_EXEC, NULL);
750 		if (error)
751 			goto out;
752 	}
753 
754 	error = gfs2_dir_search(dir, name, &inum, &type);
755 	if (error)
756 		goto out;
757 
758 	error = gfs2_glock_get(sdp, inum.no_addr, &gfs2_inode_glops,
759 			       CREATE, &gl);
760 	if (error)
761 		goto out;
762 
763 	error = gfs2_inode_get(gl, &inum, CREATE, &ipp);
764 	if (!error)
765 		gfs2_inode_min_init(ipp, type);
766 
767 	gfs2_glock_put(gl);
768 
769 out:
770 	gfs2_glock_dq_uninit(&d_gh);
771 done:
772 	if (error == -ENOENT)
773 		return NULL;
774 	if (error == 0) {
775 		inode = gfs2_ip2v(ipp);
776 		gfs2_inode_put(ipp);
777 		if (!inode)
778 			return ERR_PTR(-ENOMEM);
779 		return inode;
780 	}
781 	return ERR_PTR(error);
782 }
783 
784 static int pick_formal_ino_1(struct gfs2_sbd *sdp, uint64_t *formal_ino)
785 {
786 	struct gfs2_inode *ip = sdp->sd_ir_inode->u.generic_ip;
787 	struct buffer_head *bh;
788 	struct gfs2_inum_range ir;
789 	int error;
790 
791 	error = gfs2_trans_begin(sdp, RES_DINODE, 0);
792 	if (error)
793 		return error;
794 	mutex_lock(&sdp->sd_inum_mutex);
795 
796 	error = gfs2_meta_inode_buffer(ip, &bh);
797 	if (error) {
798 		mutex_unlock(&sdp->sd_inum_mutex);
799 		gfs2_trans_end(sdp);
800 		return error;
801 	}
802 
803 	gfs2_inum_range_in(&ir, bh->b_data + sizeof(struct gfs2_dinode));
804 
805 	if (ir.ir_length) {
806 		*formal_ino = ir.ir_start++;
807 		ir.ir_length--;
808 		gfs2_trans_add_bh(ip->i_gl, bh, 1);
809 		gfs2_inum_range_out(&ir,
810 				    bh->b_data + sizeof(struct gfs2_dinode));
811 		brelse(bh);
812 		mutex_unlock(&sdp->sd_inum_mutex);
813 		gfs2_trans_end(sdp);
814 		return 0;
815 	}
816 
817 	brelse(bh);
818 
819 	mutex_unlock(&sdp->sd_inum_mutex);
820 	gfs2_trans_end(sdp);
821 
822 	return 1;
823 }
824 
825 static int pick_formal_ino_2(struct gfs2_sbd *sdp, uint64_t *formal_ino)
826 {
827 	struct gfs2_inode *ip = sdp->sd_ir_inode->u.generic_ip;
828 	struct gfs2_inode *m_ip = sdp->sd_inum_inode->u.generic_ip;
829 	struct gfs2_holder gh;
830 	struct buffer_head *bh;
831 	struct gfs2_inum_range ir;
832 	int error;
833 
834 	error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
835 	if (error)
836 		return error;
837 
838 	error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
839 	if (error)
840 		goto out;
841 	mutex_lock(&sdp->sd_inum_mutex);
842 
843 	error = gfs2_meta_inode_buffer(ip, &bh);
844 	if (error)
845 		goto out_end_trans;
846 
847 	gfs2_inum_range_in(&ir, bh->b_data + sizeof(struct gfs2_dinode));
848 
849 	if (!ir.ir_length) {
850 		struct buffer_head *m_bh;
851 		uint64_t x, y;
852 
853 		error = gfs2_meta_inode_buffer(m_ip, &m_bh);
854 		if (error)
855 			goto out_brelse;
856 
857 		x = *(uint64_t *)(m_bh->b_data + sizeof(struct gfs2_dinode));
858 		x = y = be64_to_cpu(x);
859 		ir.ir_start = x;
860 		ir.ir_length = GFS2_INUM_QUANTUM;
861 		x += GFS2_INUM_QUANTUM;
862 		if (x < y)
863 			gfs2_consist_inode(m_ip);
864 		x = cpu_to_be64(x);
865 		gfs2_trans_add_bh(m_ip->i_gl, m_bh, 1);
866 		*(uint64_t *)(m_bh->b_data + sizeof(struct gfs2_dinode)) = x;
867 
868 		brelse(m_bh);
869 	}
870 
871 	*formal_ino = ir.ir_start++;
872 	ir.ir_length--;
873 
874 	gfs2_trans_add_bh(ip->i_gl, bh, 1);
875 	gfs2_inum_range_out(&ir, bh->b_data + sizeof(struct gfs2_dinode));
876 
877  out_brelse:
878 	brelse(bh);
879 
880  out_end_trans:
881 	mutex_unlock(&sdp->sd_inum_mutex);
882 	gfs2_trans_end(sdp);
883 
884  out:
885 	gfs2_glock_dq_uninit(&gh);
886 
887 	return error;
888 }
889 
890 static int pick_formal_ino(struct gfs2_sbd *sdp, uint64_t *inum)
891 {
892 	int error;
893 
894 	error = pick_formal_ino_1(sdp, inum);
895 	if (error <= 0)
896 		return error;
897 
898 	error = pick_formal_ino_2(sdp, inum);
899 
900 	return error;
901 }
902 
903 /**
904  * create_ok - OK to create a new on-disk inode here?
905  * @dip:  Directory in which dinode is to be created
906  * @name:  Name of new dinode
907  * @mode:
908  *
909  * Returns: errno
910  */
911 
912 static int create_ok(struct gfs2_inode *dip, struct qstr *name,
913 		     unsigned int mode)
914 {
915 	int error;
916 
917 	error = gfs2_repermission(dip->i_vnode, MAY_WRITE | MAY_EXEC, NULL);
918 	if (error)
919 		return error;
920 
921 	/*  Don't create entries in an unlinked directory  */
922 	if (!dip->i_di.di_nlink)
923 		return -EPERM;
924 
925 	error = gfs2_dir_search(dip->i_vnode, name, NULL, NULL);
926 	switch (error) {
927 	case -ENOENT:
928 		error = 0;
929 		break;
930 	case 0:
931 		return -EEXIST;
932 	default:
933 		return error;
934 	}
935 
936 	if (dip->i_di.di_entries == (uint32_t)-1)
937 		return -EFBIG;
938 	if (S_ISDIR(mode) && dip->i_di.di_nlink == (uint32_t)-1)
939 		return -EMLINK;
940 
941 	return 0;
942 }
943 
944 static void munge_mode_uid_gid(struct gfs2_inode *dip, unsigned int *mode,
945 			       unsigned int *uid, unsigned int *gid)
946 {
947 	if (dip->i_sbd->sd_args.ar_suiddir &&
948 	    (dip->i_di.di_mode & S_ISUID) &&
949 	    dip->i_di.di_uid) {
950 		if (S_ISDIR(*mode))
951 			*mode |= S_ISUID;
952 		else if (dip->i_di.di_uid != current->fsuid)
953 			*mode &= ~07111;
954 		*uid = dip->i_di.di_uid;
955 	} else
956 		*uid = current->fsuid;
957 
958 	if (dip->i_di.di_mode & S_ISGID) {
959 		if (S_ISDIR(*mode))
960 			*mode |= S_ISGID;
961 		*gid = dip->i_di.di_gid;
962 	} else
963 		*gid = current->fsgid;
964 }
965 
966 static int alloc_dinode(struct gfs2_inode *dip, struct gfs2_unlinked *ul)
967 {
968 	struct gfs2_sbd *sdp = dip->i_sbd;
969 	int error;
970 
971 	gfs2_alloc_get(dip);
972 
973 	dip->i_alloc.al_requested = RES_DINODE;
974 	error = gfs2_inplace_reserve(dip);
975 	if (error)
976 		goto out;
977 
978 	error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_UNLINKED +
979 				 RES_STATFS, 0);
980 	if (error)
981 		goto out_ipreserv;
982 
983 	ul->ul_ut.ut_inum.no_addr = gfs2_alloc_di(dip);
984 
985 	ul->ul_ut.ut_flags = GFS2_UTF_UNINIT;
986 	error = gfs2_unlinked_ondisk_add(sdp, ul);
987 
988 	gfs2_trans_end(sdp);
989 
990  out_ipreserv:
991 	gfs2_inplace_release(dip);
992 
993  out:
994 	gfs2_alloc_put(dip);
995 
996 	return error;
997 }
998 
999 /**
1000  * init_dinode - Fill in a new dinode structure
1001  * @dip: the directory this inode is being created in
1002  * @gl: The glock covering the new inode
1003  * @inum: the inode number
1004  * @mode: the file permissions
1005  * @uid:
1006  * @gid:
1007  *
1008  */
1009 
1010 static void init_dinode(struct gfs2_inode *dip, struct gfs2_glock *gl,
1011 			struct gfs2_inum *inum, unsigned int mode,
1012 			unsigned int uid, unsigned int gid)
1013 {
1014 	struct gfs2_sbd *sdp = dip->i_sbd;
1015 	struct gfs2_dinode *di;
1016 	struct buffer_head *dibh;
1017 
1018 	dibh = gfs2_meta_new(gl, inum->no_addr);
1019 	gfs2_trans_add_bh(gl, dibh, 1);
1020 	gfs2_metatype_set(dibh, GFS2_METATYPE_DI, GFS2_FORMAT_DI);
1021 	gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
1022 	di = (struct gfs2_dinode *)dibh->b_data;
1023 
1024 	di->di_num.no_formal_ino = cpu_to_be64(inum->no_formal_ino);
1025 	di->di_num.no_addr = cpu_to_be64(inum->no_addr);
1026 	di->di_mode = cpu_to_be32(mode);
1027 	di->di_uid = cpu_to_be32(uid);
1028 	di->di_gid = cpu_to_be32(gid);
1029 	di->di_nlink = cpu_to_be32(0);
1030 	di->di_size = cpu_to_be64(0);
1031 	di->di_blocks = cpu_to_be64(1);
1032 	di->di_atime = di->di_mtime = di->di_ctime = cpu_to_be64(get_seconds());
1033 	di->di_major = di->di_minor = cpu_to_be32(0);
1034 	di->di_goal_meta = di->di_goal_data = cpu_to_be64(inum->no_addr);
1035 	di->__pad[0] = di->__pad[1] = 0;
1036 	di->di_flags = cpu_to_be32(0);
1037 
1038 	if (S_ISREG(mode)) {
1039 		if ((dip->i_di.di_flags & GFS2_DIF_INHERIT_JDATA) ||
1040 		    gfs2_tune_get(sdp, gt_new_files_jdata))
1041 			di->di_flags |= cpu_to_be32(GFS2_DIF_JDATA);
1042 		if ((dip->i_di.di_flags & GFS2_DIF_INHERIT_DIRECTIO) ||
1043 		    gfs2_tune_get(sdp, gt_new_files_directio))
1044 			di->di_flags |= cpu_to_be32(GFS2_DIF_DIRECTIO);
1045 	} else if (S_ISDIR(mode)) {
1046 		di->di_flags |= cpu_to_be32(dip->i_di.di_flags &
1047 					    GFS2_DIF_INHERIT_DIRECTIO);
1048 		di->di_flags |= cpu_to_be32(dip->i_di.di_flags &
1049 					    GFS2_DIF_INHERIT_JDATA);
1050 	}
1051 
1052 	di->__pad1 = 0;
1053 	di->di_height = cpu_to_be32(0);
1054 	di->__pad2 = 0;
1055 	di->__pad3 = 0;
1056 	di->di_depth = cpu_to_be16(0);
1057 	di->di_entries = cpu_to_be32(0);
1058 	memset(&di->__pad4, 0, sizeof(di->__pad4));
1059 	di->di_eattr = cpu_to_be64(0);
1060 	memset(&di->di_reserved, 0, sizeof(di->di_reserved));
1061 
1062 	brelse(dibh);
1063 }
1064 
1065 static int make_dinode(struct gfs2_inode *dip, struct gfs2_glock *gl,
1066 		       unsigned int mode, struct gfs2_unlinked *ul)
1067 {
1068 	struct gfs2_sbd *sdp = dip->i_sbd;
1069 	unsigned int uid, gid;
1070 	int error;
1071 
1072 	munge_mode_uid_gid(dip, &mode, &uid, &gid);
1073 
1074 	gfs2_alloc_get(dip);
1075 
1076 	error = gfs2_quota_lock(dip, uid, gid);
1077 	if (error)
1078 		goto out;
1079 
1080 	error = gfs2_quota_check(dip, uid, gid);
1081 	if (error)
1082 		goto out_quota;
1083 
1084 	error = gfs2_trans_begin(sdp, RES_DINODE + RES_UNLINKED +
1085 				 RES_QUOTA, 0);
1086 	if (error)
1087 		goto out_quota;
1088 
1089 	ul->ul_ut.ut_flags = 0;
1090 	error = gfs2_unlinked_ondisk_munge(sdp, ul);
1091 
1092 	init_dinode(dip, gl, &ul->ul_ut.ut_inum,
1093 		     mode, uid, gid);
1094 
1095 	gfs2_quota_change(dip, +1, uid, gid);
1096 
1097 	gfs2_trans_end(sdp);
1098 
1099  out_quota:
1100 	gfs2_quota_unlock(dip);
1101 
1102  out:
1103 	gfs2_alloc_put(dip);
1104 
1105 	return error;
1106 }
1107 
1108 static int link_dinode(struct gfs2_inode *dip, struct qstr *name,
1109 		       struct gfs2_inode *ip, struct gfs2_unlinked *ul)
1110 {
1111 	struct gfs2_sbd *sdp = dip->i_sbd;
1112 	struct gfs2_alloc *al;
1113 	int alloc_required;
1114 	struct buffer_head *dibh;
1115 	int error;
1116 
1117 	al = gfs2_alloc_get(dip);
1118 
1119 	error = gfs2_quota_lock(dip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
1120 	if (error)
1121 		goto fail;
1122 
1123 	error = alloc_required = gfs2_diradd_alloc_required(dip->i_vnode, name);
1124 	if (alloc_required < 0)
1125 		goto fail;
1126 	if (alloc_required) {
1127 		error = gfs2_quota_check(dip, dip->i_di.di_uid,
1128 					 dip->i_di.di_gid);
1129 		if (error)
1130 			goto fail_quota_locks;
1131 
1132 		al->al_requested = sdp->sd_max_dirres;
1133 
1134 		error = gfs2_inplace_reserve(dip);
1135 		if (error)
1136 			goto fail_quota_locks;
1137 
1138 		error = gfs2_trans_begin(sdp,
1139 					 sdp->sd_max_dirres +
1140 					 al->al_rgd->rd_ri.ri_length +
1141 					 2 * RES_DINODE + RES_UNLINKED +
1142 					 RES_STATFS + RES_QUOTA, 0);
1143 		if (error)
1144 			goto fail_ipreserv;
1145 	} else {
1146 		error = gfs2_trans_begin(sdp,
1147 					 RES_LEAF +
1148 					 2 * RES_DINODE +
1149 					 RES_UNLINKED, 0);
1150 		if (error)
1151 			goto fail_quota_locks;
1152 	}
1153 
1154 	error = gfs2_dir_add(dip->i_vnode, name, &ip->i_num, IF2DT(ip->i_di.di_mode));
1155 	if (error)
1156 		goto fail_end_trans;
1157 
1158 	error = gfs2_meta_inode_buffer(ip, &dibh);
1159 	if (error)
1160 		goto fail_end_trans;
1161 	ip->i_di.di_nlink = 1;
1162 	gfs2_trans_add_bh(ip->i_gl, dibh, 1);
1163 	gfs2_dinode_out(&ip->i_di, dibh->b_data);
1164 	brelse(dibh);
1165 
1166 	error = gfs2_unlinked_ondisk_rm(sdp, ul);
1167 	if (error)
1168 		goto fail_end_trans;
1169 
1170 	return 0;
1171 
1172  fail_end_trans:
1173 	gfs2_trans_end(sdp);
1174 
1175  fail_ipreserv:
1176 	if (dip->i_alloc.al_rgd)
1177 		gfs2_inplace_release(dip);
1178 
1179  fail_quota_locks:
1180 	gfs2_quota_unlock(dip);
1181 
1182  fail:
1183 	gfs2_alloc_put(dip);
1184 
1185 	return error;
1186 }
1187 
1188 /**
1189  * gfs2_createi - Create a new inode
1190  * @ghs: An array of two holders
1191  * @name: The name of the new file
1192  * @mode: the permissions on the new inode
1193  *
1194  * @ghs[0] is an initialized holder for the directory
1195  * @ghs[1] is the holder for the inode lock
1196  *
1197  * If the return value is not NULL, the glocks on both the directory and the new
1198  * file are held.  A transaction has been started and an inplace reservation
1199  * is held, as well.
1200  *
1201  * Returns: An inode
1202  */
1203 
1204 struct inode *gfs2_createi(struct gfs2_holder *ghs, struct qstr *name,
1205 			   unsigned int mode)
1206 {
1207 	struct inode *inode;
1208 	struct gfs2_inode *dip = ghs->gh_gl->gl_object;
1209 	struct gfs2_sbd *sdp = dip->i_sbd;
1210 	struct gfs2_unlinked *ul;
1211 	struct gfs2_inode *ip;
1212 	int error;
1213 
1214 	if (!name->len || name->len > GFS2_FNAMESIZE)
1215 		return ERR_PTR(-ENAMETOOLONG);
1216 
1217 	error = gfs2_unlinked_get(sdp, &ul);
1218 	if (error)
1219 		return ERR_PTR(error);
1220 
1221 	gfs2_holder_reinit(LM_ST_EXCLUSIVE, 0, ghs);
1222 	error = gfs2_glock_nq(ghs);
1223 	if (error)
1224 		goto fail;
1225 
1226 	error = create_ok(dip, name, mode);
1227 	if (error)
1228 		goto fail_gunlock;
1229 
1230 	error = pick_formal_ino(sdp, &ul->ul_ut.ut_inum.no_formal_ino);
1231 	if (error)
1232 		goto fail_gunlock;
1233 
1234 	error = alloc_dinode(dip, ul);
1235 	if (error)
1236 		goto fail_gunlock;
1237 
1238 	if (ul->ul_ut.ut_inum.no_addr < dip->i_num.no_addr) {
1239 		gfs2_glock_dq(ghs);
1240 
1241 		error = gfs2_glock_nq_num(sdp,
1242 					  ul->ul_ut.ut_inum.no_addr,
1243 					  &gfs2_inode_glops,
1244 					  LM_ST_EXCLUSIVE, GL_SKIP,
1245 					  ghs + 1);
1246 		if (error) {
1247 			gfs2_unlinked_put(sdp, ul);
1248 			return ERR_PTR(error);
1249 		}
1250 
1251 		gfs2_holder_reinit(LM_ST_EXCLUSIVE, 0, ghs);
1252 		error = gfs2_glock_nq(ghs);
1253 		if (error) {
1254 			gfs2_glock_dq_uninit(ghs + 1);
1255 			gfs2_unlinked_put(sdp, ul);
1256 			return ERR_PTR(error);
1257 		}
1258 
1259 		error = create_ok(dip, name, mode);
1260 		if (error)
1261 			goto fail_gunlock2;
1262 	} else {
1263 		error = gfs2_glock_nq_num(sdp,
1264 					  ul->ul_ut.ut_inum.no_addr,
1265 					  &gfs2_inode_glops,
1266 					  LM_ST_EXCLUSIVE, GL_SKIP,
1267 					  ghs + 1);
1268 		if (error)
1269 			goto fail_gunlock;
1270 	}
1271 
1272 	error = make_dinode(dip, ghs[1].gh_gl, mode, ul);
1273 	if (error)
1274 		goto fail_gunlock2;
1275 
1276 	error = gfs2_inode_get(ghs[1].gh_gl, &ul->ul_ut.ut_inum, CREATE, &ip);
1277 	if (error)
1278 		goto fail_gunlock2;
1279 
1280 	error = gfs2_inode_refresh(ip);
1281 	if (error)
1282 		goto fail_iput;
1283 
1284 	error = gfs2_acl_create(dip, ip);
1285 	if (error)
1286 		goto fail_iput;
1287 
1288 	error = link_dinode(dip, name, ip, ul);
1289 	if (error)
1290 		goto fail_iput;
1291 
1292 	gfs2_unlinked_put(sdp, ul);
1293 
1294 	inode = gfs2_ip2v(ip);
1295 	gfs2_inode_put(ip);
1296 	if (!inode)
1297 		return ERR_PTR(-ENOMEM);
1298 	return inode;
1299 
1300  fail_iput:
1301 	gfs2_inode_put(ip);
1302 
1303  fail_gunlock2:
1304 	gfs2_glock_dq_uninit(ghs + 1);
1305 
1306  fail_gunlock:
1307 	gfs2_glock_dq(ghs);
1308 
1309  fail:
1310 	gfs2_unlinked_put(sdp, ul);
1311 
1312 	return ERR_PTR(error);
1313 }
1314 
1315 /**
1316  * gfs2_unlinki - Unlink a file
1317  * @dip: The inode of the directory
1318  * @name: The name of the file to be unlinked
1319  * @ip: The inode of the file to be removed
1320  *
1321  * Assumes Glocks on both dip and ip are held.
1322  *
1323  * Returns: errno
1324  */
1325 
1326 int gfs2_unlinki(struct gfs2_inode *dip, struct qstr *name,
1327 		 struct gfs2_inode *ip, struct gfs2_unlinked *ul)
1328 {
1329 	struct gfs2_sbd *sdp = dip->i_sbd;
1330 	int error;
1331 
1332 	error = gfs2_dir_del(dip, name);
1333 	if (error)
1334 		return error;
1335 
1336 	error = gfs2_change_nlink(ip, -1);
1337 	if (error)
1338 		return error;
1339 
1340 	/* If this inode is being unlinked from the directory structure,
1341 	   we need to mark that in the log so that it isn't lost during
1342 	   a crash. */
1343 
1344 	if (!ip->i_di.di_nlink) {
1345 		ul->ul_ut.ut_inum = ip->i_num;
1346 		error = gfs2_unlinked_ondisk_add(sdp, ul);
1347 		if (!error)
1348 			set_bit(GLF_STICKY, &ip->i_gl->gl_flags);
1349 	}
1350 
1351 	return error;
1352 }
1353 
1354 /**
1355  * gfs2_rmdiri - Remove a directory
1356  * @dip: The parent directory of the directory to be removed
1357  * @name: The name of the directory to be removed
1358  * @ip: The GFS2 inode of the directory to be removed
1359  *
1360  * Assumes Glocks on dip and ip are held
1361  *
1362  * Returns: errno
1363  */
1364 
1365 int gfs2_rmdiri(struct gfs2_inode *dip, struct qstr *name,
1366 		struct gfs2_inode *ip, struct gfs2_unlinked *ul)
1367 {
1368 	struct gfs2_sbd *sdp = dip->i_sbd;
1369 	struct qstr dotname;
1370 	int error;
1371 
1372 	if (ip->i_di.di_entries != 2) {
1373 		if (gfs2_consist_inode(ip))
1374 			gfs2_dinode_print(&ip->i_di);
1375 		return -EIO;
1376 	}
1377 
1378 	error = gfs2_dir_del(dip, name);
1379 	if (error)
1380 		return error;
1381 
1382 	error = gfs2_change_nlink(dip, -1);
1383 	if (error)
1384 		return error;
1385 
1386 	gfs2_str2qstr(&dotname, ".");
1387 	error = gfs2_dir_del(ip, &dotname);
1388 	if (error)
1389 		return error;
1390 
1391 	dotname.len = 2;
1392 	dotname.name = "..";
1393 	dotname.hash = gfs2_disk_hash(dotname.name, dotname.len);
1394 	error = gfs2_dir_del(ip, &dotname);
1395 	if (error)
1396 		return error;
1397 
1398 	error = gfs2_change_nlink(ip, -2);
1399 	if (error)
1400 		return error;
1401 
1402 	/* This inode is being unlinked from the directory structure and
1403 	   we need to mark that in the log so that it isn't lost during
1404 	   a crash. */
1405 
1406 	ul->ul_ut.ut_inum = ip->i_num;
1407 	error = gfs2_unlinked_ondisk_add(sdp, ul);
1408 	if (!error)
1409 		set_bit(GLF_STICKY, &ip->i_gl->gl_flags);
1410 
1411 	return error;
1412 }
1413 
1414 /*
1415  * gfs2_unlink_ok - check to see that a inode is still in a directory
1416  * @dip: the directory
1417  * @name: the name of the file
1418  * @ip: the inode
1419  *
1420  * Assumes that the lock on (at least) @dip is held.
1421  *
1422  * Returns: 0 if the parent/child relationship is correct, errno if it isn't
1423  */
1424 
1425 int gfs2_unlink_ok(struct gfs2_inode *dip, struct qstr *name,
1426 		   struct gfs2_inode *ip)
1427 {
1428 	struct gfs2_inum inum;
1429 	unsigned int type;
1430 	int error;
1431 
1432 	if (IS_IMMUTABLE(ip->i_vnode) || IS_APPEND(ip->i_vnode))
1433 		return -EPERM;
1434 
1435 	if ((dip->i_di.di_mode & S_ISVTX) &&
1436 	    dip->i_di.di_uid != current->fsuid &&
1437 	    ip->i_di.di_uid != current->fsuid &&
1438 	    !capable(CAP_FOWNER))
1439 		return -EPERM;
1440 
1441 	if (IS_APPEND(dip->i_vnode))
1442 		return -EPERM;
1443 
1444 	error = gfs2_repermission(dip->i_vnode, MAY_WRITE | MAY_EXEC, NULL);
1445 	if (error)
1446 		return error;
1447 
1448 	error = gfs2_dir_search(dip->i_vnode, name, &inum, &type);
1449 	if (error)
1450 		return error;
1451 
1452 	if (!gfs2_inum_equal(&inum, &ip->i_num))
1453 		return -ENOENT;
1454 
1455 	if (IF2DT(ip->i_di.di_mode) != type) {
1456 		gfs2_consist_inode(dip);
1457 		return -EIO;
1458 	}
1459 
1460 	return 0;
1461 }
1462 
1463 /*
1464  * gfs2_ok_to_move - check if it's ok to move a directory to another directory
1465  * @this: move this
1466  * @to: to here
1467  *
1468  * Follow @to back to the root and make sure we don't encounter @this
1469  * Assumes we already hold the rename lock.
1470  *
1471  * Returns: errno
1472  */
1473 
1474 int gfs2_ok_to_move(struct gfs2_inode *this, struct gfs2_inode *to)
1475 {
1476 	struct inode *dir = to->i_vnode;
1477 	struct super_block *sb = dir->i_sb;
1478 	struct inode *tmp;
1479 	struct qstr dotdot;
1480 	int error = 0;
1481 
1482 	gfs2_str2qstr(&dotdot, "..");
1483 
1484 	igrab(dir);
1485 
1486 	for (;;) {
1487 		if (dir == this->i_vnode) {
1488 			error = -EINVAL;
1489 			break;
1490 		}
1491 		if (dir == sb->s_root->d_inode) {
1492 			error = 0;
1493 			break;
1494 		}
1495 
1496 		tmp = gfs2_lookupi(dir, &dotdot, 1, NULL);
1497 		if (IS_ERR(tmp)) {
1498 			error = PTR_ERR(tmp);
1499 			break;
1500 		}
1501 
1502 		iput(dir);
1503 		dir = tmp;
1504 	}
1505 
1506 	iput(dir);
1507 
1508 	return error;
1509 }
1510 
1511 /**
1512  * gfs2_readlinki - return the contents of a symlink
1513  * @ip: the symlink's inode
1514  * @buf: a pointer to the buffer to be filled
1515  * @len: a pointer to the length of @buf
1516  *
1517  * If @buf is too small, a piece of memory is kmalloc()ed and needs
1518  * to be freed by the caller.
1519  *
1520  * Returns: errno
1521  */
1522 
1523 int gfs2_readlinki(struct gfs2_inode *ip, char **buf, unsigned int *len)
1524 {
1525 	struct gfs2_holder i_gh;
1526 	struct buffer_head *dibh;
1527 	unsigned int x;
1528 	int error;
1529 
1530 	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &i_gh);
1531 	error = gfs2_glock_nq_atime(&i_gh);
1532 	if (error) {
1533 		gfs2_holder_uninit(&i_gh);
1534 		return error;
1535 	}
1536 
1537 	if (!ip->i_di.di_size) {
1538 		gfs2_consist_inode(ip);
1539 		error = -EIO;
1540 		goto out;
1541 	}
1542 
1543 	error = gfs2_meta_inode_buffer(ip, &dibh);
1544 	if (error)
1545 		goto out;
1546 
1547 	x = ip->i_di.di_size + 1;
1548 	if (x > *len) {
1549 		*buf = kmalloc(x, GFP_KERNEL);
1550 		if (!*buf) {
1551 			error = -ENOMEM;
1552 			goto out_brelse;
1553 		}
1554 	}
1555 
1556 	memcpy(*buf, dibh->b_data + sizeof(struct gfs2_dinode), x);
1557 	*len = x;
1558 
1559  out_brelse:
1560 	brelse(dibh);
1561 
1562  out:
1563 	gfs2_glock_dq_uninit(&i_gh);
1564 
1565 	return error;
1566 }
1567 
1568 /**
1569  * gfs2_glock_nq_atime - Acquire a hold on an inode's glock, and
1570  *       conditionally update the inode's atime
1571  * @gh: the holder to acquire
1572  *
1573  * Tests atime (access time) for gfs2_read, gfs2_readdir and gfs2_mmap
1574  * Update if the difference between the current time and the inode's current
1575  * atime is greater than an interval specified at mount.
1576  *
1577  * Returns: errno
1578  */
1579 
1580 int gfs2_glock_nq_atime(struct gfs2_holder *gh)
1581 {
1582 	struct gfs2_glock *gl = gh->gh_gl;
1583 	struct gfs2_sbd *sdp = gl->gl_sbd;
1584 	struct gfs2_inode *ip = gl->gl_object;
1585 	int64_t curtime, quantum = gfs2_tune_get(sdp, gt_atime_quantum);
1586 	unsigned int state;
1587 	int flags;
1588 	int error;
1589 
1590 	if (gfs2_assert_warn(sdp, gh->gh_flags & GL_ATIME) ||
1591 	    gfs2_assert_warn(sdp, !(gh->gh_flags & GL_ASYNC)) ||
1592 	    gfs2_assert_warn(sdp, gl->gl_ops == &gfs2_inode_glops))
1593 		return -EINVAL;
1594 
1595 	state = gh->gh_state;
1596 	flags = gh->gh_flags;
1597 
1598 	error = gfs2_glock_nq(gh);
1599 	if (error)
1600 		return error;
1601 
1602 	if (test_bit(SDF_NOATIME, &sdp->sd_flags) ||
1603 	    (sdp->sd_vfs->s_flags & MS_RDONLY))
1604 		return 0;
1605 
1606 	curtime = get_seconds();
1607 	if (curtime - ip->i_di.di_atime >= quantum) {
1608 		gfs2_glock_dq(gh);
1609 		gfs2_holder_reinit(LM_ST_EXCLUSIVE,
1610 				  gh->gh_flags & ~LM_FLAG_ANY,
1611 				  gh);
1612 		error = gfs2_glock_nq(gh);
1613 		if (error)
1614 			return error;
1615 
1616 		/* Verify that atime hasn't been updated while we were
1617 		   trying to get exclusive lock. */
1618 
1619 		curtime = get_seconds();
1620 		if (curtime - ip->i_di.di_atime >= quantum) {
1621 			struct buffer_head *dibh;
1622 
1623 			error = gfs2_trans_begin(sdp, RES_DINODE, 0);
1624 			if (error == -EROFS)
1625 				return 0;
1626 			if (error)
1627 				goto fail;
1628 
1629 			error = gfs2_meta_inode_buffer(ip, &dibh);
1630 			if (error)
1631 				goto fail_end_trans;
1632 
1633 			ip->i_di.di_atime = curtime;
1634 
1635 			gfs2_trans_add_bh(ip->i_gl, dibh, 1);
1636 			gfs2_dinode_out(&ip->i_di, dibh->b_data);
1637 			brelse(dibh);
1638 
1639 			gfs2_trans_end(sdp);
1640 		}
1641 
1642 		/* If someone else has asked for the glock,
1643 		   unlock and let them have it. Then reacquire
1644 		   in the original state. */
1645 		if (gfs2_glock_is_blocking(gl)) {
1646 			gfs2_glock_dq(gh);
1647 			gfs2_holder_reinit(state, flags, gh);
1648 			return gfs2_glock_nq(gh);
1649 		}
1650 	}
1651 
1652 	return 0;
1653 
1654  fail_end_trans:
1655 	gfs2_trans_end(sdp);
1656 
1657  fail:
1658 	gfs2_glock_dq(gh);
1659 
1660 	return error;
1661 }
1662 
1663 /**
1664  * glock_compare_atime - Compare two struct gfs2_glock structures for sort
1665  * @arg_a: the first structure
1666  * @arg_b: the second structure
1667  *
1668  * Returns: 1 if A > B
1669  *         -1 if A < B
1670  *          0 if A = B
1671  */
1672 
1673 static int glock_compare_atime(const void *arg_a, const void *arg_b)
1674 {
1675 	struct gfs2_holder *gh_a = *(struct gfs2_holder **)arg_a;
1676 	struct gfs2_holder *gh_b = *(struct gfs2_holder **)arg_b;
1677 	struct lm_lockname *a = &gh_a->gh_gl->gl_name;
1678 	struct lm_lockname *b = &gh_b->gh_gl->gl_name;
1679 	int ret = 0;
1680 
1681 	if (a->ln_number > b->ln_number)
1682 		ret = 1;
1683 	else if (a->ln_number < b->ln_number)
1684 		ret = -1;
1685 	else {
1686 		if (gh_a->gh_state == LM_ST_SHARED &&
1687 		    gh_b->gh_state == LM_ST_EXCLUSIVE)
1688 			ret = 1;
1689 		else if (gh_a->gh_state == LM_ST_SHARED &&
1690 			 (gh_b->gh_flags & GL_ATIME))
1691 			ret = 1;
1692 	}
1693 
1694 	return ret;
1695 }
1696 
1697 /**
1698  * gfs2_glock_nq_m_atime - acquire multiple glocks where one may need an
1699  *      atime update
1700  * @num_gh: the number of structures
1701  * @ghs: an array of struct gfs2_holder structures
1702  *
1703  * Returns: 0 on success (all glocks acquired),
1704  *          errno on failure (no glocks acquired)
1705  */
1706 
1707 int gfs2_glock_nq_m_atime(unsigned int num_gh, struct gfs2_holder *ghs)
1708 {
1709 	struct gfs2_holder **p;
1710 	unsigned int x;
1711 	int error = 0;
1712 
1713 	if (!num_gh)
1714 		return 0;
1715 
1716 	if (num_gh == 1) {
1717 		ghs->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC);
1718 		if (ghs->gh_flags & GL_ATIME)
1719 			error = gfs2_glock_nq_atime(ghs);
1720 		else
1721 			error = gfs2_glock_nq(ghs);
1722 		return error;
1723 	}
1724 
1725 	p = kcalloc(num_gh, sizeof(struct gfs2_holder *), GFP_KERNEL);
1726 	if (!p)
1727 		return -ENOMEM;
1728 
1729 	for (x = 0; x < num_gh; x++)
1730 		p[x] = &ghs[x];
1731 
1732 	sort(p, num_gh, sizeof(struct gfs2_holder *), glock_compare_atime,NULL);
1733 
1734 	for (x = 0; x < num_gh; x++) {
1735 		p[x]->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC);
1736 
1737 		if (p[x]->gh_flags & GL_ATIME)
1738 			error = gfs2_glock_nq_atime(p[x]);
1739 		else
1740 			error = gfs2_glock_nq(p[x]);
1741 
1742 		if (error) {
1743 			while (x--)
1744 				gfs2_glock_dq(p[x]);
1745 			break;
1746 		}
1747 	}
1748 
1749 	kfree(p);
1750 
1751 	return error;
1752 }
1753 
1754 /**
1755  * gfs2_try_toss_vnode - See if we can toss a vnode from memory
1756  * @ip: the inode
1757  *
1758  * Returns:  1 if the vnode was tossed
1759  */
1760 
1761 void gfs2_try_toss_vnode(struct gfs2_inode *ip)
1762 {
1763 	struct inode *inode;
1764 
1765 	inode = gfs2_ip2v_lookup(ip);
1766 	if (!inode)
1767 		return;
1768 
1769 	d_prune_aliases(inode);
1770 
1771 	if (S_ISDIR(ip->i_di.di_mode)) {
1772 		struct list_head *head = &inode->i_dentry;
1773 		struct dentry *d = NULL;
1774 
1775 		spin_lock(&dcache_lock);
1776 		if (list_empty(head))
1777 			spin_unlock(&dcache_lock);
1778 		else {
1779 			d = list_entry(head->next, struct dentry, d_alias);
1780 			dget_locked(d);
1781 			spin_unlock(&dcache_lock);
1782 
1783 			if (have_submounts(d))
1784 				dput(d);
1785 			else {
1786 				shrink_dcache_parent(d);
1787 				dput(d);
1788 				d_prune_aliases(inode);
1789 			}
1790 		}
1791 	}
1792 
1793 	inode->i_nlink = 0;
1794 	iput(inode);
1795 }
1796 
1797 
1798 static int
1799 __gfs2_setattr_simple(struct gfs2_inode *ip, struct iattr *attr)
1800 {
1801 	struct buffer_head *dibh;
1802 	int error;
1803 
1804 	error = gfs2_meta_inode_buffer(ip, &dibh);
1805 	if (!error) {
1806 		error = inode_setattr(ip->i_vnode, attr);
1807 		gfs2_assert_warn(ip->i_sbd, !error);
1808 		gfs2_inode_attr_out(ip);
1809 
1810 		gfs2_trans_add_bh(ip->i_gl, dibh, 1);
1811 		gfs2_dinode_out(&ip->i_di, dibh->b_data);
1812 		brelse(dibh);
1813 	}
1814 	return error;
1815 }
1816 
1817 /**
1818  * gfs2_setattr_simple -
1819  * @ip:
1820  * @attr:
1821  *
1822  * Called with a reference on the vnode.
1823  *
1824  * Returns: errno
1825  */
1826 
1827 int gfs2_setattr_simple(struct gfs2_inode *ip, struct iattr *attr)
1828 {
1829 	int error;
1830 
1831 	if (current->journal_info)
1832 		return __gfs2_setattr_simple(ip, attr);
1833 
1834 	error = gfs2_trans_begin(ip->i_sbd, RES_DINODE, 0);
1835 	if (error)
1836 		return error;
1837 
1838 	error = __gfs2_setattr_simple(ip, attr);
1839 
1840 	gfs2_trans_end(ip->i_sbd);
1841 
1842 	return error;
1843 }
1844 
1845 int gfs2_repermission(struct inode *inode, int mask, struct nameidata *nd)
1846 {
1847 	return permission(inode, mask, nd);
1848 }
1849 
1850