xref: /linux/fs/gfs2/inode.c (revision c4c11dd160a8cc98f402c4e12f94b1572e822ffd)
1 /*
2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
3  * Copyright (C) 2004-2011 Red Hat, Inc.  All rights reserved.
4  *
5  * This copyrighted material is made available to anyone wishing to use,
6  * modify, copy, or redistribute it subject to the terms and conditions
7  * of the GNU General Public License version 2.
8  */
9 
10 #include <linux/slab.h>
11 #include <linux/spinlock.h>
12 #include <linux/completion.h>
13 #include <linux/buffer_head.h>
14 #include <linux/namei.h>
15 #include <linux/mm.h>
16 #include <linux/xattr.h>
17 #include <linux/posix_acl.h>
18 #include <linux/gfs2_ondisk.h>
19 #include <linux/crc32.h>
20 #include <linux/fiemap.h>
21 #include <linux/security.h>
22 #include <asm/uaccess.h>
23 
24 #include "gfs2.h"
25 #include "incore.h"
26 #include "acl.h"
27 #include "bmap.h"
28 #include "dir.h"
29 #include "xattr.h"
30 #include "glock.h"
31 #include "inode.h"
32 #include "meta_io.h"
33 #include "quota.h"
34 #include "rgrp.h"
35 #include "trans.h"
36 #include "util.h"
37 #include "super.h"
38 #include "glops.h"
39 
40 struct gfs2_skip_data {
41 	u64 no_addr;
42 	int skipped;
43 	int non_block;
44 };
45 
46 static int iget_test(struct inode *inode, void *opaque)
47 {
48 	struct gfs2_inode *ip = GFS2_I(inode);
49 	struct gfs2_skip_data *data = opaque;
50 
51 	if (ip->i_no_addr == data->no_addr) {
52 		if (data->non_block &&
53 		    inode->i_state & (I_FREEING|I_CLEAR|I_WILL_FREE)) {
54 			data->skipped = 1;
55 			return 0;
56 		}
57 		return 1;
58 	}
59 	return 0;
60 }
61 
62 static int iget_set(struct inode *inode, void *opaque)
63 {
64 	struct gfs2_inode *ip = GFS2_I(inode);
65 	struct gfs2_skip_data *data = opaque;
66 
67 	if (data->skipped)
68 		return -ENOENT;
69 	inode->i_ino = (unsigned long)(data->no_addr);
70 	ip->i_no_addr = data->no_addr;
71 	return 0;
72 }
73 
74 struct inode *gfs2_ilookup(struct super_block *sb, u64 no_addr, int non_block)
75 {
76 	unsigned long hash = (unsigned long)no_addr;
77 	struct gfs2_skip_data data;
78 
79 	data.no_addr = no_addr;
80 	data.skipped = 0;
81 	data.non_block = non_block;
82 	return ilookup5(sb, hash, iget_test, &data);
83 }
84 
85 static struct inode *gfs2_iget(struct super_block *sb, u64 no_addr,
86 			       int non_block)
87 {
88 	struct gfs2_skip_data data;
89 	unsigned long hash = (unsigned long)no_addr;
90 
91 	data.no_addr = no_addr;
92 	data.skipped = 0;
93 	data.non_block = non_block;
94 	return iget5_locked(sb, hash, iget_test, iget_set, &data);
95 }
96 
97 /**
98  * gfs2_set_iop - Sets inode operations
99  * @inode: The inode with correct i_mode filled in
100  *
101  * GFS2 lookup code fills in vfs inode contents based on info obtained
102  * from directory entry inside gfs2_inode_lookup().
103  */
104 
105 static void gfs2_set_iop(struct inode *inode)
106 {
107 	struct gfs2_sbd *sdp = GFS2_SB(inode);
108 	umode_t mode = inode->i_mode;
109 
110 	if (S_ISREG(mode)) {
111 		inode->i_op = &gfs2_file_iops;
112 		if (gfs2_localflocks(sdp))
113 			inode->i_fop = &gfs2_file_fops_nolock;
114 		else
115 			inode->i_fop = &gfs2_file_fops;
116 	} else if (S_ISDIR(mode)) {
117 		inode->i_op = &gfs2_dir_iops;
118 		if (gfs2_localflocks(sdp))
119 			inode->i_fop = &gfs2_dir_fops_nolock;
120 		else
121 			inode->i_fop = &gfs2_dir_fops;
122 	} else if (S_ISLNK(mode)) {
123 		inode->i_op = &gfs2_symlink_iops;
124 	} else {
125 		inode->i_op = &gfs2_file_iops;
126 		init_special_inode(inode, inode->i_mode, inode->i_rdev);
127 	}
128 }
129 
130 /**
131  * gfs2_inode_lookup - Lookup an inode
132  * @sb: The super block
133  * @no_addr: The inode number
134  * @type: The type of the inode
135  * non_block: Can we block on inodes that are being freed?
136  *
137  * Returns: A VFS inode, or an error
138  */
139 
140 struct inode *gfs2_inode_lookup(struct super_block *sb, unsigned int type,
141 				u64 no_addr, u64 no_formal_ino, int non_block)
142 {
143 	struct inode *inode;
144 	struct gfs2_inode *ip;
145 	struct gfs2_glock *io_gl = NULL;
146 	int error;
147 
148 	inode = gfs2_iget(sb, no_addr, non_block);
149 	ip = GFS2_I(inode);
150 
151 	if (!inode)
152 		return ERR_PTR(-ENOBUFS);
153 
154 	if (inode->i_state & I_NEW) {
155 		struct gfs2_sbd *sdp = GFS2_SB(inode);
156 		ip->i_no_formal_ino = no_formal_ino;
157 
158 		error = gfs2_glock_get(sdp, no_addr, &gfs2_inode_glops, CREATE, &ip->i_gl);
159 		if (unlikely(error))
160 			goto fail;
161 		ip->i_gl->gl_object = ip;
162 
163 		error = gfs2_glock_get(sdp, no_addr, &gfs2_iopen_glops, CREATE, &io_gl);
164 		if (unlikely(error))
165 			goto fail_put;
166 
167 		set_bit(GIF_INVALID, &ip->i_flags);
168 		error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED, GL_EXACT, &ip->i_iopen_gh);
169 		if (unlikely(error))
170 			goto fail_iopen;
171 
172 		ip->i_iopen_gh.gh_gl->gl_object = ip;
173 		gfs2_glock_put(io_gl);
174 		io_gl = NULL;
175 
176 		if (type == DT_UNKNOWN) {
177 			/* Inode glock must be locked already */
178 			error = gfs2_inode_refresh(GFS2_I(inode));
179 			if (error)
180 				goto fail_refresh;
181 		} else {
182 			inode->i_mode = DT2IF(type);
183 		}
184 
185 		gfs2_set_iop(inode);
186 		unlock_new_inode(inode);
187 	}
188 
189 	return inode;
190 
191 fail_refresh:
192 	ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
193 	ip->i_iopen_gh.gh_gl->gl_object = NULL;
194 	gfs2_glock_dq_uninit(&ip->i_iopen_gh);
195 fail_iopen:
196 	if (io_gl)
197 		gfs2_glock_put(io_gl);
198 fail_put:
199 	ip->i_gl->gl_object = NULL;
200 	gfs2_glock_put(ip->i_gl);
201 fail:
202 	iget_failed(inode);
203 	return ERR_PTR(error);
204 }
205 
206 struct inode *gfs2_lookup_by_inum(struct gfs2_sbd *sdp, u64 no_addr,
207 				  u64 *no_formal_ino, unsigned int blktype)
208 {
209 	struct super_block *sb = sdp->sd_vfs;
210 	struct gfs2_holder i_gh;
211 	struct inode *inode = NULL;
212 	int error;
213 
214 	/* Must not read in block until block type is verified */
215 	error = gfs2_glock_nq_num(sdp, no_addr, &gfs2_inode_glops,
216 				  LM_ST_EXCLUSIVE, GL_SKIP, &i_gh);
217 	if (error)
218 		return ERR_PTR(error);
219 
220 	error = gfs2_check_blk_type(sdp, no_addr, blktype);
221 	if (error)
222 		goto fail;
223 
224 	inode = gfs2_inode_lookup(sb, DT_UNKNOWN, no_addr, 0, 1);
225 	if (IS_ERR(inode))
226 		goto fail;
227 
228 	/* Two extra checks for NFS only */
229 	if (no_formal_ino) {
230 		error = -ESTALE;
231 		if (GFS2_I(inode)->i_no_formal_ino != *no_formal_ino)
232 			goto fail_iput;
233 
234 		error = -EIO;
235 		if (GFS2_I(inode)->i_diskflags & GFS2_DIF_SYSTEM)
236 			goto fail_iput;
237 
238 		error = 0;
239 	}
240 
241 fail:
242 	gfs2_glock_dq_uninit(&i_gh);
243 	return error ? ERR_PTR(error) : inode;
244 fail_iput:
245 	iput(inode);
246 	goto fail;
247 }
248 
249 
250 struct inode *gfs2_lookup_simple(struct inode *dip, const char *name)
251 {
252 	struct qstr qstr;
253 	struct inode *inode;
254 	gfs2_str2qstr(&qstr, name);
255 	inode = gfs2_lookupi(dip, &qstr, 1);
256 	/* gfs2_lookupi has inconsistent callers: vfs
257 	 * related routines expect NULL for no entry found,
258 	 * gfs2_lookup_simple callers expect ENOENT
259 	 * and do not check for NULL.
260 	 */
261 	if (inode == NULL)
262 		return ERR_PTR(-ENOENT);
263 	else
264 		return inode;
265 }
266 
267 
268 /**
269  * gfs2_lookupi - Look up a filename in a directory and return its inode
270  * @d_gh: An initialized holder for the directory glock
271  * @name: The name of the inode to look for
272  * @is_root: If 1, ignore the caller's permissions
273  * @i_gh: An uninitialized holder for the new inode glock
274  *
275  * This can be called via the VFS filldir function when NFS is doing
276  * a readdirplus and the inode which its intending to stat isn't
277  * already in cache. In this case we must not take the directory glock
278  * again, since the readdir call will have already taken that lock.
279  *
280  * Returns: errno
281  */
282 
283 struct inode *gfs2_lookupi(struct inode *dir, const struct qstr *name,
284 			   int is_root)
285 {
286 	struct super_block *sb = dir->i_sb;
287 	struct gfs2_inode *dip = GFS2_I(dir);
288 	struct gfs2_holder d_gh;
289 	int error = 0;
290 	struct inode *inode = NULL;
291 	int unlock = 0;
292 
293 	if (!name->len || name->len > GFS2_FNAMESIZE)
294 		return ERR_PTR(-ENAMETOOLONG);
295 
296 	if ((name->len == 1 && memcmp(name->name, ".", 1) == 0) ||
297 	    (name->len == 2 && memcmp(name->name, "..", 2) == 0 &&
298 	     dir == sb->s_root->d_inode)) {
299 		igrab(dir);
300 		return dir;
301 	}
302 
303 	if (gfs2_glock_is_locked_by_me(dip->i_gl) == NULL) {
304 		error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh);
305 		if (error)
306 			return ERR_PTR(error);
307 		unlock = 1;
308 	}
309 
310 	if (!is_root) {
311 		error = gfs2_permission(dir, MAY_EXEC);
312 		if (error)
313 			goto out;
314 	}
315 
316 	inode = gfs2_dir_search(dir, name, false);
317 	if (IS_ERR(inode))
318 		error = PTR_ERR(inode);
319 out:
320 	if (unlock)
321 		gfs2_glock_dq_uninit(&d_gh);
322 	if (error == -ENOENT)
323 		return NULL;
324 	return inode ? inode : ERR_PTR(error);
325 }
326 
327 /**
328  * create_ok - OK to create a new on-disk inode here?
329  * @dip:  Directory in which dinode is to be created
330  * @name:  Name of new dinode
331  * @mode:
332  *
333  * Returns: errno
334  */
335 
336 static int create_ok(struct gfs2_inode *dip, const struct qstr *name,
337 		     umode_t mode)
338 {
339 	int error;
340 
341 	error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC);
342 	if (error)
343 		return error;
344 
345 	/*  Don't create entries in an unlinked directory  */
346 	if (!dip->i_inode.i_nlink)
347 		return -ENOENT;
348 
349 	if (dip->i_entries == (u32)-1)
350 		return -EFBIG;
351 	if (S_ISDIR(mode) && dip->i_inode.i_nlink == (u32)-1)
352 		return -EMLINK;
353 
354 	return 0;
355 }
356 
357 static void munge_mode_uid_gid(const struct gfs2_inode *dip,
358 			       struct inode *inode)
359 {
360 	if (GFS2_SB(&dip->i_inode)->sd_args.ar_suiddir &&
361 	    (dip->i_inode.i_mode & S_ISUID) &&
362 	    !uid_eq(dip->i_inode.i_uid, GLOBAL_ROOT_UID)) {
363 		if (S_ISDIR(inode->i_mode))
364 			inode->i_mode |= S_ISUID;
365 		else if (!uid_eq(dip->i_inode.i_uid, current_fsuid()))
366 			inode->i_mode &= ~07111;
367 		inode->i_uid = dip->i_inode.i_uid;
368 	} else
369 		inode->i_uid = current_fsuid();
370 
371 	if (dip->i_inode.i_mode & S_ISGID) {
372 		if (S_ISDIR(inode->i_mode))
373 			inode->i_mode |= S_ISGID;
374 		inode->i_gid = dip->i_inode.i_gid;
375 	} else
376 		inode->i_gid = current_fsgid();
377 }
378 
379 static int alloc_dinode(struct gfs2_inode *ip, u32 flags)
380 {
381 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
382 	int error;
383 	int dblocks = 1;
384 
385 	error = gfs2_quota_lock_check(ip);
386 	if (error)
387 		goto out;
388 
389 	error = gfs2_inplace_reserve(ip, RES_DINODE, flags);
390 	if (error)
391 		goto out_quota;
392 
393 	error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_STATFS + RES_QUOTA, 0);
394 	if (error)
395 		goto out_ipreserv;
396 
397 	error = gfs2_alloc_blocks(ip, &ip->i_no_addr, &dblocks, 1, &ip->i_generation);
398 	ip->i_no_formal_ino = ip->i_generation;
399 	ip->i_inode.i_ino = ip->i_no_addr;
400 	ip->i_goal = ip->i_no_addr;
401 
402 	gfs2_trans_end(sdp);
403 
404 out_ipreserv:
405 	gfs2_inplace_release(ip);
406 out_quota:
407 	gfs2_quota_unlock(ip);
408 out:
409 	return error;
410 }
411 
412 static void gfs2_init_dir(struct buffer_head *dibh,
413 			  const struct gfs2_inode *parent)
414 {
415 	struct gfs2_dinode *di = (struct gfs2_dinode *)dibh->b_data;
416 	struct gfs2_dirent *dent = (struct gfs2_dirent *)(di+1);
417 
418 	gfs2_qstr2dirent(&gfs2_qdot, GFS2_DIRENT_SIZE(gfs2_qdot.len), dent);
419 	dent->de_inum = di->di_num; /* already GFS2 endian */
420 	dent->de_type = cpu_to_be16(DT_DIR);
421 
422 	dent = (struct gfs2_dirent *)((char*)dent + GFS2_DIRENT_SIZE(1));
423 	gfs2_qstr2dirent(&gfs2_qdotdot, dibh->b_size - GFS2_DIRENT_SIZE(1) - sizeof(struct gfs2_dinode), dent);
424 	gfs2_inum_out(parent, dent);
425 	dent->de_type = cpu_to_be16(DT_DIR);
426 
427 }
428 
429 /**
430  * init_dinode - Fill in a new dinode structure
431  * @dip: The directory this inode is being created in
432  * @ip: The inode
433  * @symname: The symlink destination (if a symlink)
434  * @bhp: The buffer head (returned to caller)
435  *
436  */
437 
438 static void init_dinode(struct gfs2_inode *dip, struct gfs2_inode *ip,
439 			const char *symname)
440 {
441 	struct gfs2_dinode *di;
442 	struct buffer_head *dibh;
443 
444 	dibh = gfs2_meta_new(ip->i_gl, ip->i_no_addr);
445 	gfs2_trans_add_meta(ip->i_gl, dibh);
446 	di = (struct gfs2_dinode *)dibh->b_data;
447 	gfs2_dinode_out(ip, di);
448 
449 	di->di_major = cpu_to_be32(MAJOR(ip->i_inode.i_rdev));
450 	di->di_minor = cpu_to_be32(MINOR(ip->i_inode.i_rdev));
451 	di->__pad1 = 0;
452 	di->__pad2 = 0;
453 	di->__pad3 = 0;
454 	memset(&di->__pad4, 0, sizeof(di->__pad4));
455 	memset(&di->di_reserved, 0, sizeof(di->di_reserved));
456 	gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
457 
458 	switch(ip->i_inode.i_mode & S_IFMT) {
459 	case S_IFDIR:
460 		gfs2_init_dir(dibh, dip);
461 		break;
462 	case S_IFLNK:
463 		memcpy(dibh->b_data + sizeof(struct gfs2_dinode), symname, ip->i_inode.i_size);
464 		break;
465 	}
466 
467 	set_buffer_uptodate(dibh);
468 	brelse(dibh);
469 }
470 
471 static int link_dinode(struct gfs2_inode *dip, const struct qstr *name,
472 		       struct gfs2_inode *ip, int arq)
473 {
474 	struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
475 	int error;
476 
477 	if (arq) {
478 		error = gfs2_quota_lock_check(dip);
479 		if (error)
480 			goto fail_quota_locks;
481 
482 		error = gfs2_inplace_reserve(dip, sdp->sd_max_dirres, 0);
483 		if (error)
484 			goto fail_quota_locks;
485 
486 		error = gfs2_trans_begin(sdp, sdp->sd_max_dirres +
487 					 dip->i_rgd->rd_length +
488 					 2 * RES_DINODE +
489 					 RES_STATFS + RES_QUOTA, 0);
490 		if (error)
491 			goto fail_ipreserv;
492 	} else {
493 		error = gfs2_trans_begin(sdp, RES_LEAF + 2 * RES_DINODE, 0);
494 		if (error)
495 			goto fail_quota_locks;
496 	}
497 
498 	error = gfs2_dir_add(&dip->i_inode, name, ip);
499 	if (error)
500 		goto fail_end_trans;
501 
502 fail_end_trans:
503 	gfs2_trans_end(sdp);
504 fail_ipreserv:
505 	gfs2_inplace_release(dip);
506 fail_quota_locks:
507 	gfs2_quota_unlock(dip);
508 	return error;
509 }
510 
511 static int gfs2_initxattrs(struct inode *inode, const struct xattr *xattr_array,
512 		    void *fs_info)
513 {
514 	const struct xattr *xattr;
515 	int err = 0;
516 
517 	for (xattr = xattr_array; xattr->name != NULL; xattr++) {
518 		err = __gfs2_xattr_set(inode, xattr->name, xattr->value,
519 				       xattr->value_len, 0,
520 				       GFS2_EATYPE_SECURITY);
521 		if (err < 0)
522 			break;
523 	}
524 	return err;
525 }
526 
527 static int gfs2_security_init(struct gfs2_inode *dip, struct gfs2_inode *ip,
528 			      const struct qstr *qstr)
529 {
530 	return security_inode_init_security(&ip->i_inode, &dip->i_inode, qstr,
531 					    &gfs2_initxattrs, NULL);
532 }
533 
534 /**
535  * gfs2_create_inode - Create a new inode
536  * @dir: The parent directory
537  * @dentry: The new dentry
538  * @file: If non-NULL, the file which is being opened
539  * @mode: The permissions on the new inode
540  * @dev: For device nodes, this is the device number
541  * @symname: For symlinks, this is the link destination
542  * @size: The initial size of the inode (ignored for directories)
543  *
544  * Returns: 0 on success, or error code
545  */
546 
547 static int gfs2_create_inode(struct inode *dir, struct dentry *dentry,
548 			     struct file *file,
549 			     umode_t mode, dev_t dev, const char *symname,
550 			     unsigned int size, int excl, int *opened)
551 {
552 	const struct qstr *name = &dentry->d_name;
553 	struct gfs2_holder ghs[2];
554 	struct inode *inode = NULL;
555 	struct gfs2_inode *dip = GFS2_I(dir), *ip;
556 	struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
557 	struct gfs2_glock *io_gl;
558 	struct dentry *d;
559 	int error;
560 	u32 aflags = 0;
561 	int arq;
562 
563 	if (!name->len || name->len > GFS2_FNAMESIZE)
564 		return -ENAMETOOLONG;
565 
566 	error = gfs2_rs_alloc(dip);
567 	if (error)
568 		return error;
569 
570 	error = gfs2_rindex_update(sdp);
571 	if (error)
572 		return error;
573 
574 	error = gfs2_glock_nq_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
575 	if (error)
576 		goto fail;
577 
578 	error = create_ok(dip, name, mode);
579 	if (error)
580 		goto fail_gunlock;
581 
582 	inode = gfs2_dir_search(dir, &dentry->d_name, !S_ISREG(mode) || excl);
583 	error = PTR_ERR(inode);
584 	if (!IS_ERR(inode)) {
585 		d = d_splice_alias(inode, dentry);
586 		error = 0;
587 		if (file && !IS_ERR(d)) {
588 			if (d == NULL)
589 				d = dentry;
590 			if (S_ISREG(inode->i_mode))
591 				error = finish_open(file, d, gfs2_open_common, opened);
592 			else
593 				error = finish_no_open(file, d);
594 		}
595 		gfs2_glock_dq_uninit(ghs);
596 		if (IS_ERR(d))
597 			return PTR_RET(d);
598 		return error;
599 	} else if (error != -ENOENT) {
600 		goto fail_gunlock;
601 	}
602 
603 	arq = error = gfs2_diradd_alloc_required(dir, name);
604 	if (error < 0)
605 		goto fail_gunlock;
606 
607 	inode = new_inode(sdp->sd_vfs);
608 	error = -ENOMEM;
609 	if (!inode)
610 		goto fail_gunlock;
611 
612 	ip = GFS2_I(inode);
613 	error = gfs2_rs_alloc(ip);
614 	if (error)
615 		goto fail_free_inode;
616 
617 	inode->i_mode = mode;
618 	set_nlink(inode, S_ISDIR(mode) ? 2 : 1);
619 	inode->i_rdev = dev;
620 	inode->i_size = size;
621 	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
622 	gfs2_set_inode_blocks(inode, 1);
623 	munge_mode_uid_gid(dip, inode);
624 	ip->i_goal = dip->i_goal;
625 	ip->i_diskflags = 0;
626 	ip->i_eattr = 0;
627 	ip->i_height = 0;
628 	ip->i_depth = 0;
629 	ip->i_entries = 0;
630 
631 	switch(mode & S_IFMT) {
632 	case S_IFREG:
633 		if ((dip->i_diskflags & GFS2_DIF_INHERIT_JDATA) ||
634 		    gfs2_tune_get(sdp, gt_new_files_jdata))
635 			ip->i_diskflags |= GFS2_DIF_JDATA;
636 		gfs2_set_aops(inode);
637 		break;
638 	case S_IFDIR:
639 		ip->i_diskflags |= (dip->i_diskflags & GFS2_DIF_INHERIT_JDATA);
640 		ip->i_diskflags |= GFS2_DIF_JDATA;
641 		ip->i_entries = 2;
642 		break;
643 	}
644 	gfs2_set_inode_flags(inode);
645 
646 	if ((GFS2_I(sdp->sd_root_dir->d_inode) == dip) ||
647 	    (dip->i_diskflags & GFS2_DIF_TOPDIR))
648 		aflags |= GFS2_AF_ORLOV;
649 
650 	error = alloc_dinode(ip, aflags);
651 	if (error)
652 		goto fail_free_inode;
653 
654 	error = gfs2_glock_get(sdp, ip->i_no_addr, &gfs2_inode_glops, CREATE, &ip->i_gl);
655 	if (error)
656 		goto fail_free_inode;
657 
658 	ip->i_gl->gl_object = ip;
659 	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, ghs + 1);
660 	if (error)
661 		goto fail_free_inode;
662 
663 	error = gfs2_trans_begin(sdp, RES_DINODE, 0);
664 	if (error)
665 		goto fail_gunlock2;
666 
667 	init_dinode(dip, ip, symname);
668 	gfs2_trans_end(sdp);
669 
670 	error = gfs2_glock_get(sdp, ip->i_no_addr, &gfs2_iopen_glops, CREATE, &io_gl);
671 	if (error)
672 		goto fail_gunlock2;
673 
674 	error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED, GL_EXACT, &ip->i_iopen_gh);
675 	if (error)
676 		goto fail_gunlock2;
677 
678 	ip->i_iopen_gh.gh_gl->gl_object = ip;
679 	gfs2_glock_put(io_gl);
680 	gfs2_set_iop(inode);
681 	insert_inode_hash(inode);
682 
683 	error = gfs2_acl_create(dip, inode);
684 	if (error)
685 		goto fail_gunlock3;
686 
687 	error = gfs2_security_init(dip, ip, name);
688 	if (error)
689 		goto fail_gunlock3;
690 
691 	error = link_dinode(dip, name, ip, arq);
692 	if (error)
693 		goto fail_gunlock3;
694 
695 	mark_inode_dirty(inode);
696 	d_instantiate(dentry, inode);
697 	if (file)
698 		error = finish_open(file, dentry, gfs2_open_common, opened);
699 	gfs2_glock_dq_uninit(ghs);
700 	gfs2_glock_dq_uninit(ghs + 1);
701 	return error;
702 
703 fail_gunlock3:
704 	gfs2_glock_dq_uninit(ghs + 1);
705 	if (ip->i_gl)
706 		gfs2_glock_put(ip->i_gl);
707 	goto fail_gunlock;
708 
709 fail_gunlock2:
710 	gfs2_glock_dq_uninit(ghs + 1);
711 fail_free_inode:
712 	if (ip->i_gl)
713 		gfs2_glock_put(ip->i_gl);
714 	gfs2_rs_delete(ip);
715 	free_inode_nonrcu(inode);
716 	inode = NULL;
717 fail_gunlock:
718 	gfs2_glock_dq_uninit(ghs);
719 	if (inode && !IS_ERR(inode)) {
720 		clear_nlink(inode);
721 		mark_inode_dirty(inode);
722 		set_bit(GIF_ALLOC_FAILED, &GFS2_I(inode)->i_flags);
723 		iput(inode);
724 	}
725 fail:
726 	return error;
727 }
728 
729 /**
730  * gfs2_create - Create a file
731  * @dir: The directory in which to create the file
732  * @dentry: The dentry of the new file
733  * @mode: The mode of the new file
734  *
735  * Returns: errno
736  */
737 
738 static int gfs2_create(struct inode *dir, struct dentry *dentry,
739 		       umode_t mode, bool excl)
740 {
741 	return gfs2_create_inode(dir, dentry, NULL, S_IFREG | mode, 0, NULL, 0, excl, NULL);
742 }
743 
744 /**
745  * __gfs2_lookup - Look up a filename in a directory and return its inode
746  * @dir: The directory inode
747  * @dentry: The dentry of the new inode
748  * @file: File to be opened
749  * @opened: atomic_open flags
750  *
751  *
752  * Returns: errno
753  */
754 
755 static struct dentry *__gfs2_lookup(struct inode *dir, struct dentry *dentry,
756 				    struct file *file, int *opened)
757 {
758 	struct inode *inode;
759 	struct dentry *d;
760 	struct gfs2_holder gh;
761 	struct gfs2_glock *gl;
762 	int error;
763 
764 	inode = gfs2_lookupi(dir, &dentry->d_name, 0);
765 	if (!inode)
766 		return NULL;
767 	if (IS_ERR(inode))
768 		return ERR_CAST(inode);
769 
770 	gl = GFS2_I(inode)->i_gl;
771 	error = gfs2_glock_nq_init(gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
772 	if (error) {
773 		iput(inode);
774 		return ERR_PTR(error);
775 	}
776 
777 	d = d_splice_alias(inode, dentry);
778 	if (file && S_ISREG(inode->i_mode))
779 		error = finish_open(file, dentry, gfs2_open_common, opened);
780 
781 	gfs2_glock_dq_uninit(&gh);
782 	if (error)
783 		return ERR_PTR(error);
784 	return d;
785 }
786 
787 static struct dentry *gfs2_lookup(struct inode *dir, struct dentry *dentry,
788 				  unsigned flags)
789 {
790 	return __gfs2_lookup(dir, dentry, NULL, NULL);
791 }
792 
793 /**
794  * gfs2_link - Link to a file
795  * @old_dentry: The inode to link
796  * @dir: Add link to this directory
797  * @dentry: The name of the link
798  *
799  * Link the inode in "old_dentry" into the directory "dir" with the
800  * name in "dentry".
801  *
802  * Returns: errno
803  */
804 
805 static int gfs2_link(struct dentry *old_dentry, struct inode *dir,
806 		     struct dentry *dentry)
807 {
808 	struct gfs2_inode *dip = GFS2_I(dir);
809 	struct gfs2_sbd *sdp = GFS2_SB(dir);
810 	struct inode *inode = old_dentry->d_inode;
811 	struct gfs2_inode *ip = GFS2_I(inode);
812 	struct gfs2_holder ghs[2];
813 	struct buffer_head *dibh;
814 	int alloc_required;
815 	int error;
816 
817 	if (S_ISDIR(inode->i_mode))
818 		return -EPERM;
819 
820 	error = gfs2_rs_alloc(dip);
821 	if (error)
822 		return error;
823 
824 	gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
825 	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + 1);
826 
827 	error = gfs2_glock_nq(ghs); /* parent */
828 	if (error)
829 		goto out_parent;
830 
831 	error = gfs2_glock_nq(ghs + 1); /* child */
832 	if (error)
833 		goto out_child;
834 
835 	error = -ENOENT;
836 	if (inode->i_nlink == 0)
837 		goto out_gunlock;
838 
839 	error = gfs2_permission(dir, MAY_WRITE | MAY_EXEC);
840 	if (error)
841 		goto out_gunlock;
842 
843 	error = gfs2_dir_check(dir, &dentry->d_name, NULL);
844 	switch (error) {
845 	case -ENOENT:
846 		break;
847 	case 0:
848 		error = -EEXIST;
849 	default:
850 		goto out_gunlock;
851 	}
852 
853 	error = -EINVAL;
854 	if (!dip->i_inode.i_nlink)
855 		goto out_gunlock;
856 	error = -EFBIG;
857 	if (dip->i_entries == (u32)-1)
858 		goto out_gunlock;
859 	error = -EPERM;
860 	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
861 		goto out_gunlock;
862 	error = -EINVAL;
863 	if (!ip->i_inode.i_nlink)
864 		goto out_gunlock;
865 	error = -EMLINK;
866 	if (ip->i_inode.i_nlink == (u32)-1)
867 		goto out_gunlock;
868 
869 	alloc_required = error = gfs2_diradd_alloc_required(dir, &dentry->d_name);
870 	if (error < 0)
871 		goto out_gunlock;
872 	error = 0;
873 
874 	if (alloc_required) {
875 		error = gfs2_quota_lock_check(dip);
876 		if (error)
877 			goto out_gunlock;
878 
879 		error = gfs2_inplace_reserve(dip, sdp->sd_max_dirres, 0);
880 		if (error)
881 			goto out_gunlock_q;
882 
883 		error = gfs2_trans_begin(sdp, sdp->sd_max_dirres +
884 					 gfs2_rg_blocks(dip, sdp->sd_max_dirres) +
885 					 2 * RES_DINODE + RES_STATFS +
886 					 RES_QUOTA, 0);
887 		if (error)
888 			goto out_ipres;
889 	} else {
890 		error = gfs2_trans_begin(sdp, 2 * RES_DINODE + RES_LEAF, 0);
891 		if (error)
892 			goto out_ipres;
893 	}
894 
895 	error = gfs2_meta_inode_buffer(ip, &dibh);
896 	if (error)
897 		goto out_end_trans;
898 
899 	error = gfs2_dir_add(dir, &dentry->d_name, ip);
900 	if (error)
901 		goto out_brelse;
902 
903 	gfs2_trans_add_meta(ip->i_gl, dibh);
904 	inc_nlink(&ip->i_inode);
905 	ip->i_inode.i_ctime = CURRENT_TIME;
906 	ihold(inode);
907 	d_instantiate(dentry, inode);
908 	mark_inode_dirty(inode);
909 
910 out_brelse:
911 	brelse(dibh);
912 out_end_trans:
913 	gfs2_trans_end(sdp);
914 out_ipres:
915 	if (alloc_required)
916 		gfs2_inplace_release(dip);
917 out_gunlock_q:
918 	if (alloc_required)
919 		gfs2_quota_unlock(dip);
920 out_gunlock:
921 	gfs2_glock_dq(ghs + 1);
922 out_child:
923 	gfs2_glock_dq(ghs);
924 out_parent:
925 	gfs2_holder_uninit(ghs);
926 	gfs2_holder_uninit(ghs + 1);
927 	return error;
928 }
929 
930 /*
931  * gfs2_unlink_ok - check to see that a inode is still in a directory
932  * @dip: the directory
933  * @name: the name of the file
934  * @ip: the inode
935  *
936  * Assumes that the lock on (at least) @dip is held.
937  *
938  * Returns: 0 if the parent/child relationship is correct, errno if it isn't
939  */
940 
941 static int gfs2_unlink_ok(struct gfs2_inode *dip, const struct qstr *name,
942 			  const struct gfs2_inode *ip)
943 {
944 	int error;
945 
946 	if (IS_IMMUTABLE(&ip->i_inode) || IS_APPEND(&ip->i_inode))
947 		return -EPERM;
948 
949 	if ((dip->i_inode.i_mode & S_ISVTX) &&
950 	    !uid_eq(dip->i_inode.i_uid, current_fsuid()) &&
951 	    !uid_eq(ip->i_inode.i_uid, current_fsuid()) && !capable(CAP_FOWNER))
952 		return -EPERM;
953 
954 	if (IS_APPEND(&dip->i_inode))
955 		return -EPERM;
956 
957 	error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC);
958 	if (error)
959 		return error;
960 
961 	error = gfs2_dir_check(&dip->i_inode, name, ip);
962 	if (error)
963 		return error;
964 
965 	return 0;
966 }
967 
968 /**
969  * gfs2_unlink_inode - Removes an inode from its parent dir and unlinks it
970  * @dip: The parent directory
971  * @name: The name of the entry in the parent directory
972  * @inode: The inode to be removed
973  *
974  * Called with all the locks and in a transaction. This will only be
975  * called for a directory after it has been checked to ensure it is empty.
976  *
977  * Returns: 0 on success, or an error
978  */
979 
980 static int gfs2_unlink_inode(struct gfs2_inode *dip,
981 			     const struct dentry *dentry)
982 {
983 	struct inode *inode = dentry->d_inode;
984 	struct gfs2_inode *ip = GFS2_I(inode);
985 	int error;
986 
987 	error = gfs2_dir_del(dip, dentry);
988 	if (error)
989 		return error;
990 
991 	ip->i_entries = 0;
992 	inode->i_ctime = CURRENT_TIME;
993 	if (S_ISDIR(inode->i_mode))
994 		clear_nlink(inode);
995 	else
996 		drop_nlink(inode);
997 	mark_inode_dirty(inode);
998 	if (inode->i_nlink == 0)
999 		gfs2_unlink_di(inode);
1000 	return 0;
1001 }
1002 
1003 
1004 /**
1005  * gfs2_unlink - Unlink an inode (this does rmdir as well)
1006  * @dir: The inode of the directory containing the inode to unlink
1007  * @dentry: The file itself
1008  *
1009  * This routine uses the type of the inode as a flag to figure out
1010  * whether this is an unlink or an rmdir.
1011  *
1012  * Returns: errno
1013  */
1014 
1015 static int gfs2_unlink(struct inode *dir, struct dentry *dentry)
1016 {
1017 	struct gfs2_inode *dip = GFS2_I(dir);
1018 	struct gfs2_sbd *sdp = GFS2_SB(dir);
1019 	struct inode *inode = dentry->d_inode;
1020 	struct gfs2_inode *ip = GFS2_I(inode);
1021 	struct gfs2_holder ghs[3];
1022 	struct gfs2_rgrpd *rgd;
1023 	int error;
1024 
1025 	error = gfs2_rindex_update(sdp);
1026 	if (error)
1027 		return error;
1028 
1029 	error = -EROFS;
1030 
1031 	gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
1032 	gfs2_holder_init(ip->i_gl,  LM_ST_EXCLUSIVE, 0, ghs + 1);
1033 
1034 	rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr, 1);
1035 	if (!rgd)
1036 		goto out_inodes;
1037 
1038 	gfs2_holder_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, ghs + 2);
1039 
1040 
1041 	error = gfs2_glock_nq(ghs); /* parent */
1042 	if (error)
1043 		goto out_parent;
1044 
1045 	error = gfs2_glock_nq(ghs + 1); /* child */
1046 	if (error)
1047 		goto out_child;
1048 
1049 	error = -ENOENT;
1050 	if (inode->i_nlink == 0)
1051 		goto out_rgrp;
1052 
1053 	if (S_ISDIR(inode->i_mode)) {
1054 		error = -ENOTEMPTY;
1055 		if (ip->i_entries > 2 || inode->i_nlink > 2)
1056 			goto out_rgrp;
1057 	}
1058 
1059 	error = gfs2_glock_nq(ghs + 2); /* rgrp */
1060 	if (error)
1061 		goto out_rgrp;
1062 
1063 	error = gfs2_unlink_ok(dip, &dentry->d_name, ip);
1064 	if (error)
1065 		goto out_gunlock;
1066 
1067 	error = gfs2_trans_begin(sdp, 2*RES_DINODE + 3*RES_LEAF + RES_RG_BIT, 0);
1068 	if (error)
1069 		goto out_end_trans;
1070 
1071 	error = gfs2_unlink_inode(dip, dentry);
1072 
1073 out_end_trans:
1074 	gfs2_trans_end(sdp);
1075 out_gunlock:
1076 	gfs2_glock_dq(ghs + 2);
1077 out_rgrp:
1078 	gfs2_glock_dq(ghs + 1);
1079 out_child:
1080 	gfs2_glock_dq(ghs);
1081 out_parent:
1082 	gfs2_holder_uninit(ghs + 2);
1083 out_inodes:
1084 	gfs2_holder_uninit(ghs + 1);
1085 	gfs2_holder_uninit(ghs);
1086 	return error;
1087 }
1088 
1089 /**
1090  * gfs2_symlink - Create a symlink
1091  * @dir: The directory to create the symlink in
1092  * @dentry: The dentry to put the symlink in
1093  * @symname: The thing which the link points to
1094  *
1095  * Returns: errno
1096  */
1097 
1098 static int gfs2_symlink(struct inode *dir, struct dentry *dentry,
1099 			const char *symname)
1100 {
1101 	struct gfs2_sbd *sdp = GFS2_SB(dir);
1102 	unsigned int size;
1103 
1104 	size = strlen(symname);
1105 	if (size > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode) - 1)
1106 		return -ENAMETOOLONG;
1107 
1108 	return gfs2_create_inode(dir, dentry, NULL, S_IFLNK | S_IRWXUGO, 0, symname, size, 0, NULL);
1109 }
1110 
1111 /**
1112  * gfs2_mkdir - Make a directory
1113  * @dir: The parent directory of the new one
1114  * @dentry: The dentry of the new directory
1115  * @mode: The mode of the new directory
1116  *
1117  * Returns: errno
1118  */
1119 
1120 static int gfs2_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
1121 {
1122 	struct gfs2_sbd *sdp = GFS2_SB(dir);
1123 	unsigned dsize = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode);
1124 	return gfs2_create_inode(dir, dentry, NULL, S_IFDIR | mode, 0, NULL, dsize, 0, NULL);
1125 }
1126 
1127 /**
1128  * gfs2_mknod - Make a special file
1129  * @dir: The directory in which the special file will reside
1130  * @dentry: The dentry of the special file
1131  * @mode: The mode of the special file
1132  * @dev: The device specification of the special file
1133  *
1134  */
1135 
1136 static int gfs2_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
1137 		      dev_t dev)
1138 {
1139 	return gfs2_create_inode(dir, dentry, NULL, mode, dev, NULL, 0, 0, NULL);
1140 }
1141 
1142 /**
1143  * gfs2_atomic_open - Atomically open a file
1144  * @dir: The directory
1145  * @dentry: The proposed new entry
1146  * @file: The proposed new struct file
1147  * @flags: open flags
1148  * @mode: File mode
1149  * @opened: Flag to say whether the file has been opened or not
1150  *
1151  * Returns: error code or 0 for success
1152  */
1153 
1154 static int gfs2_atomic_open(struct inode *dir, struct dentry *dentry,
1155                             struct file *file, unsigned flags,
1156                             umode_t mode, int *opened)
1157 {
1158 	struct dentry *d;
1159 	bool excl = !!(flags & O_EXCL);
1160 
1161 	d = __gfs2_lookup(dir, dentry, file, opened);
1162 	if (IS_ERR(d))
1163 		return PTR_ERR(d);
1164 	if (d == NULL)
1165 		d = dentry;
1166 	if (d->d_inode) {
1167 		if (!(*opened & FILE_OPENED))
1168 			return finish_no_open(file, d);
1169 		return 0;
1170 	}
1171 
1172 	if (!(flags & O_CREAT))
1173 		return -ENOENT;
1174 
1175 	return gfs2_create_inode(dir, dentry, file, S_IFREG | mode, 0, NULL, 0, excl, opened);
1176 }
1177 
1178 /*
1179  * gfs2_ok_to_move - check if it's ok to move a directory to another directory
1180  * @this: move this
1181  * @to: to here
1182  *
1183  * Follow @to back to the root and make sure we don't encounter @this
1184  * Assumes we already hold the rename lock.
1185  *
1186  * Returns: errno
1187  */
1188 
1189 static int gfs2_ok_to_move(struct gfs2_inode *this, struct gfs2_inode *to)
1190 {
1191 	struct inode *dir = &to->i_inode;
1192 	struct super_block *sb = dir->i_sb;
1193 	struct inode *tmp;
1194 	int error = 0;
1195 
1196 	igrab(dir);
1197 
1198 	for (;;) {
1199 		if (dir == &this->i_inode) {
1200 			error = -EINVAL;
1201 			break;
1202 		}
1203 		if (dir == sb->s_root->d_inode) {
1204 			error = 0;
1205 			break;
1206 		}
1207 
1208 		tmp = gfs2_lookupi(dir, &gfs2_qdotdot, 1);
1209 		if (IS_ERR(tmp)) {
1210 			error = PTR_ERR(tmp);
1211 			break;
1212 		}
1213 
1214 		iput(dir);
1215 		dir = tmp;
1216 	}
1217 
1218 	iput(dir);
1219 
1220 	return error;
1221 }
1222 
1223 /**
1224  * gfs2_rename - Rename a file
1225  * @odir: Parent directory of old file name
1226  * @odentry: The old dentry of the file
1227  * @ndir: Parent directory of new file name
1228  * @ndentry: The new dentry of the file
1229  *
1230  * Returns: errno
1231  */
1232 
1233 static int gfs2_rename(struct inode *odir, struct dentry *odentry,
1234 		       struct inode *ndir, struct dentry *ndentry)
1235 {
1236 	struct gfs2_inode *odip = GFS2_I(odir);
1237 	struct gfs2_inode *ndip = GFS2_I(ndir);
1238 	struct gfs2_inode *ip = GFS2_I(odentry->d_inode);
1239 	struct gfs2_inode *nip = NULL;
1240 	struct gfs2_sbd *sdp = GFS2_SB(odir);
1241 	struct gfs2_holder ghs[5], r_gh = { .gh_gl = NULL, };
1242 	struct gfs2_rgrpd *nrgd;
1243 	unsigned int num_gh;
1244 	int dir_rename = 0;
1245 	int alloc_required = 0;
1246 	unsigned int x;
1247 	int error;
1248 
1249 	if (ndentry->d_inode) {
1250 		nip = GFS2_I(ndentry->d_inode);
1251 		if (ip == nip)
1252 			return 0;
1253 	}
1254 
1255 	error = gfs2_rindex_update(sdp);
1256 	if (error)
1257 		return error;
1258 
1259 	error = gfs2_rs_alloc(ndip);
1260 	if (error)
1261 		return error;
1262 
1263 	if (odip != ndip) {
1264 		error = gfs2_glock_nq_init(sdp->sd_rename_gl, LM_ST_EXCLUSIVE,
1265 					   0, &r_gh);
1266 		if (error)
1267 			goto out;
1268 
1269 		if (S_ISDIR(ip->i_inode.i_mode)) {
1270 			dir_rename = 1;
1271 			/* don't move a dirctory into it's subdir */
1272 			error = gfs2_ok_to_move(ip, ndip);
1273 			if (error)
1274 				goto out_gunlock_r;
1275 		}
1276 	}
1277 
1278 	num_gh = 1;
1279 	gfs2_holder_init(odip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
1280 	if (odip != ndip) {
1281 		gfs2_holder_init(ndip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
1282 		num_gh++;
1283 	}
1284 	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
1285 	num_gh++;
1286 
1287 	if (nip) {
1288 		gfs2_holder_init(nip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
1289 		num_gh++;
1290 		/* grab the resource lock for unlink flag twiddling
1291 		 * this is the case of the target file already existing
1292 		 * so we unlink before doing the rename
1293 		 */
1294 		nrgd = gfs2_blk2rgrpd(sdp, nip->i_no_addr, 1);
1295 		if (nrgd)
1296 			gfs2_holder_init(nrgd->rd_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh++);
1297 	}
1298 
1299 	for (x = 0; x < num_gh; x++) {
1300 		error = gfs2_glock_nq(ghs + x);
1301 		if (error)
1302 			goto out_gunlock;
1303 	}
1304 
1305 	error = -ENOENT;
1306 	if (ip->i_inode.i_nlink == 0)
1307 		goto out_gunlock;
1308 
1309 	/* Check out the old directory */
1310 
1311 	error = gfs2_unlink_ok(odip, &odentry->d_name, ip);
1312 	if (error)
1313 		goto out_gunlock;
1314 
1315 	/* Check out the new directory */
1316 
1317 	if (nip) {
1318 		error = gfs2_unlink_ok(ndip, &ndentry->d_name, nip);
1319 		if (error)
1320 			goto out_gunlock;
1321 
1322 		if (nip->i_inode.i_nlink == 0) {
1323 			error = -EAGAIN;
1324 			goto out_gunlock;
1325 		}
1326 
1327 		if (S_ISDIR(nip->i_inode.i_mode)) {
1328 			if (nip->i_entries < 2) {
1329 				gfs2_consist_inode(nip);
1330 				error = -EIO;
1331 				goto out_gunlock;
1332 			}
1333 			if (nip->i_entries > 2) {
1334 				error = -ENOTEMPTY;
1335 				goto out_gunlock;
1336 			}
1337 		}
1338 	} else {
1339 		error = gfs2_permission(ndir, MAY_WRITE | MAY_EXEC);
1340 		if (error)
1341 			goto out_gunlock;
1342 
1343 		error = gfs2_dir_check(ndir, &ndentry->d_name, NULL);
1344 		switch (error) {
1345 		case -ENOENT:
1346 			error = 0;
1347 			break;
1348 		case 0:
1349 			error = -EEXIST;
1350 		default:
1351 			goto out_gunlock;
1352 		};
1353 
1354 		if (odip != ndip) {
1355 			if (!ndip->i_inode.i_nlink) {
1356 				error = -ENOENT;
1357 				goto out_gunlock;
1358 			}
1359 			if (ndip->i_entries == (u32)-1) {
1360 				error = -EFBIG;
1361 				goto out_gunlock;
1362 			}
1363 			if (S_ISDIR(ip->i_inode.i_mode) &&
1364 			    ndip->i_inode.i_nlink == (u32)-1) {
1365 				error = -EMLINK;
1366 				goto out_gunlock;
1367 			}
1368 		}
1369 	}
1370 
1371 	/* Check out the dir to be renamed */
1372 
1373 	if (dir_rename) {
1374 		error = gfs2_permission(odentry->d_inode, MAY_WRITE);
1375 		if (error)
1376 			goto out_gunlock;
1377 	}
1378 
1379 	if (nip == NULL)
1380 		alloc_required = gfs2_diradd_alloc_required(ndir, &ndentry->d_name);
1381 	error = alloc_required;
1382 	if (error < 0)
1383 		goto out_gunlock;
1384 
1385 	if (alloc_required) {
1386 		error = gfs2_quota_lock_check(ndip);
1387 		if (error)
1388 			goto out_gunlock;
1389 
1390 		error = gfs2_inplace_reserve(ndip, sdp->sd_max_dirres, 0);
1391 		if (error)
1392 			goto out_gunlock_q;
1393 
1394 		error = gfs2_trans_begin(sdp, sdp->sd_max_dirres +
1395 					 gfs2_rg_blocks(ndip, sdp->sd_max_dirres) +
1396 					 4 * RES_DINODE + 4 * RES_LEAF +
1397 					 RES_STATFS + RES_QUOTA + 4, 0);
1398 		if (error)
1399 			goto out_ipreserv;
1400 	} else {
1401 		error = gfs2_trans_begin(sdp, 4 * RES_DINODE +
1402 					 5 * RES_LEAF + 4, 0);
1403 		if (error)
1404 			goto out_gunlock;
1405 	}
1406 
1407 	/* Remove the target file, if it exists */
1408 
1409 	if (nip)
1410 		error = gfs2_unlink_inode(ndip, ndentry);
1411 
1412 	if (dir_rename) {
1413 		error = gfs2_dir_mvino(ip, &gfs2_qdotdot, ndip, DT_DIR);
1414 		if (error)
1415 			goto out_end_trans;
1416 	} else {
1417 		struct buffer_head *dibh;
1418 		error = gfs2_meta_inode_buffer(ip, &dibh);
1419 		if (error)
1420 			goto out_end_trans;
1421 		ip->i_inode.i_ctime = CURRENT_TIME;
1422 		gfs2_trans_add_meta(ip->i_gl, dibh);
1423 		gfs2_dinode_out(ip, dibh->b_data);
1424 		brelse(dibh);
1425 	}
1426 
1427 	error = gfs2_dir_del(odip, odentry);
1428 	if (error)
1429 		goto out_end_trans;
1430 
1431 	error = gfs2_dir_add(ndir, &ndentry->d_name, ip);
1432 	if (error)
1433 		goto out_end_trans;
1434 
1435 out_end_trans:
1436 	gfs2_trans_end(sdp);
1437 out_ipreserv:
1438 	if (alloc_required)
1439 		gfs2_inplace_release(ndip);
1440 out_gunlock_q:
1441 	if (alloc_required)
1442 		gfs2_quota_unlock(ndip);
1443 out_gunlock:
1444 	while (x--) {
1445 		gfs2_glock_dq(ghs + x);
1446 		gfs2_holder_uninit(ghs + x);
1447 	}
1448 out_gunlock_r:
1449 	if (r_gh.gh_gl)
1450 		gfs2_glock_dq_uninit(&r_gh);
1451 out:
1452 	return error;
1453 }
1454 
1455 /**
1456  * gfs2_follow_link - Follow a symbolic link
1457  * @dentry: The dentry of the link
1458  * @nd: Data that we pass to vfs_follow_link()
1459  *
1460  * This can handle symlinks of any size.
1461  *
1462  * Returns: 0 on success or error code
1463  */
1464 
1465 static void *gfs2_follow_link(struct dentry *dentry, struct nameidata *nd)
1466 {
1467 	struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
1468 	struct gfs2_holder i_gh;
1469 	struct buffer_head *dibh;
1470 	unsigned int size;
1471 	char *buf;
1472 	int error;
1473 
1474 	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
1475 	error = gfs2_glock_nq(&i_gh);
1476 	if (error) {
1477 		gfs2_holder_uninit(&i_gh);
1478 		nd_set_link(nd, ERR_PTR(error));
1479 		return NULL;
1480 	}
1481 
1482 	size = (unsigned int)i_size_read(&ip->i_inode);
1483 	if (size == 0) {
1484 		gfs2_consist_inode(ip);
1485 		buf = ERR_PTR(-EIO);
1486 		goto out;
1487 	}
1488 
1489 	error = gfs2_meta_inode_buffer(ip, &dibh);
1490 	if (error) {
1491 		buf = ERR_PTR(error);
1492 		goto out;
1493 	}
1494 
1495 	buf = kzalloc(size + 1, GFP_NOFS);
1496 	if (!buf)
1497 		buf = ERR_PTR(-ENOMEM);
1498 	else
1499 		memcpy(buf, dibh->b_data + sizeof(struct gfs2_dinode), size);
1500 	brelse(dibh);
1501 out:
1502 	gfs2_glock_dq_uninit(&i_gh);
1503 	nd_set_link(nd, buf);
1504 	return NULL;
1505 }
1506 
1507 static void gfs2_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
1508 {
1509 	char *s = nd_get_link(nd);
1510 	if (!IS_ERR(s))
1511 		kfree(s);
1512 }
1513 
1514 /**
1515  * gfs2_permission -
1516  * @inode: The inode
1517  * @mask: The mask to be tested
1518  * @flags: Indicates whether this is an RCU path walk or not
1519  *
1520  * This may be called from the VFS directly, or from within GFS2 with the
1521  * inode locked, so we look to see if the glock is already locked and only
1522  * lock the glock if its not already been done.
1523  *
1524  * Returns: errno
1525  */
1526 
1527 int gfs2_permission(struct inode *inode, int mask)
1528 {
1529 	struct gfs2_inode *ip;
1530 	struct gfs2_holder i_gh;
1531 	int error;
1532 	int unlock = 0;
1533 
1534 
1535 	ip = GFS2_I(inode);
1536 	if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
1537 		if (mask & MAY_NOT_BLOCK)
1538 			return -ECHILD;
1539 		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
1540 		if (error)
1541 			return error;
1542 		unlock = 1;
1543 	}
1544 
1545 	if ((mask & MAY_WRITE) && IS_IMMUTABLE(inode))
1546 		error = -EACCES;
1547 	else
1548 		error = generic_permission(inode, mask);
1549 	if (unlock)
1550 		gfs2_glock_dq_uninit(&i_gh);
1551 
1552 	return error;
1553 }
1554 
1555 static int __gfs2_setattr_simple(struct inode *inode, struct iattr *attr)
1556 {
1557 	setattr_copy(inode, attr);
1558 	mark_inode_dirty(inode);
1559 	return 0;
1560 }
1561 
1562 /**
1563  * gfs2_setattr_simple -
1564  * @ip:
1565  * @attr:
1566  *
1567  * Returns: errno
1568  */
1569 
1570 int gfs2_setattr_simple(struct inode *inode, struct iattr *attr)
1571 {
1572 	int error;
1573 
1574 	if (current->journal_info)
1575 		return __gfs2_setattr_simple(inode, attr);
1576 
1577 	error = gfs2_trans_begin(GFS2_SB(inode), RES_DINODE, 0);
1578 	if (error)
1579 		return error;
1580 
1581 	error = __gfs2_setattr_simple(inode, attr);
1582 	gfs2_trans_end(GFS2_SB(inode));
1583 	return error;
1584 }
1585 
1586 static int setattr_chown(struct inode *inode, struct iattr *attr)
1587 {
1588 	struct gfs2_inode *ip = GFS2_I(inode);
1589 	struct gfs2_sbd *sdp = GFS2_SB(inode);
1590 	kuid_t ouid, nuid;
1591 	kgid_t ogid, ngid;
1592 	int error;
1593 
1594 	ouid = inode->i_uid;
1595 	ogid = inode->i_gid;
1596 	nuid = attr->ia_uid;
1597 	ngid = attr->ia_gid;
1598 
1599 	if (!(attr->ia_valid & ATTR_UID) || uid_eq(ouid, nuid))
1600 		ouid = nuid = NO_UID_QUOTA_CHANGE;
1601 	if (!(attr->ia_valid & ATTR_GID) || gid_eq(ogid, ngid))
1602 		ogid = ngid = NO_GID_QUOTA_CHANGE;
1603 
1604 	error = gfs2_quota_lock(ip, nuid, ngid);
1605 	if (error)
1606 		return error;
1607 
1608 	if (!uid_eq(ouid, NO_UID_QUOTA_CHANGE) ||
1609 	    !gid_eq(ogid, NO_GID_QUOTA_CHANGE)) {
1610 		error = gfs2_quota_check(ip, nuid, ngid);
1611 		if (error)
1612 			goto out_gunlock_q;
1613 	}
1614 
1615 	error = gfs2_trans_begin(sdp, RES_DINODE + 2 * RES_QUOTA, 0);
1616 	if (error)
1617 		goto out_gunlock_q;
1618 
1619 	error = gfs2_setattr_simple(inode, attr);
1620 	if (error)
1621 		goto out_end_trans;
1622 
1623 	if (!uid_eq(ouid, NO_UID_QUOTA_CHANGE) ||
1624 	    !gid_eq(ogid, NO_GID_QUOTA_CHANGE)) {
1625 		u64 blocks = gfs2_get_inode_blocks(&ip->i_inode);
1626 		gfs2_quota_change(ip, -blocks, ouid, ogid);
1627 		gfs2_quota_change(ip, blocks, nuid, ngid);
1628 	}
1629 
1630 out_end_trans:
1631 	gfs2_trans_end(sdp);
1632 out_gunlock_q:
1633 	gfs2_quota_unlock(ip);
1634 	return error;
1635 }
1636 
1637 /**
1638  * gfs2_setattr - Change attributes on an inode
1639  * @dentry: The dentry which is changing
1640  * @attr: The structure describing the change
1641  *
1642  * The VFS layer wants to change one or more of an inodes attributes.  Write
1643  * that change out to disk.
1644  *
1645  * Returns: errno
1646  */
1647 
1648 static int gfs2_setattr(struct dentry *dentry, struct iattr *attr)
1649 {
1650 	struct inode *inode = dentry->d_inode;
1651 	struct gfs2_inode *ip = GFS2_I(inode);
1652 	struct gfs2_holder i_gh;
1653 	int error;
1654 
1655 	error = gfs2_rs_alloc(ip);
1656 	if (error)
1657 		return error;
1658 
1659 	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1660 	if (error)
1661 		return error;
1662 
1663 	error = -EPERM;
1664 	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
1665 		goto out;
1666 
1667 	error = inode_change_ok(inode, attr);
1668 	if (error)
1669 		goto out;
1670 
1671 	if (attr->ia_valid & ATTR_SIZE)
1672 		error = gfs2_setattr_size(inode, attr->ia_size);
1673 	else if (attr->ia_valid & (ATTR_UID | ATTR_GID))
1674 		error = setattr_chown(inode, attr);
1675 	else if ((attr->ia_valid & ATTR_MODE) && IS_POSIXACL(inode))
1676 		error = gfs2_acl_chmod(ip, attr);
1677 	else
1678 		error = gfs2_setattr_simple(inode, attr);
1679 
1680 out:
1681 	if (!error)
1682 		mark_inode_dirty(inode);
1683 	gfs2_glock_dq_uninit(&i_gh);
1684 	return error;
1685 }
1686 
1687 /**
1688  * gfs2_getattr - Read out an inode's attributes
1689  * @mnt: The vfsmount the inode is being accessed from
1690  * @dentry: The dentry to stat
1691  * @stat: The inode's stats
1692  *
1693  * This may be called from the VFS directly, or from within GFS2 with the
1694  * inode locked, so we look to see if the glock is already locked and only
1695  * lock the glock if its not already been done. Note that its the NFS
1696  * readdirplus operation which causes this to be called (from filldir)
1697  * with the glock already held.
1698  *
1699  * Returns: errno
1700  */
1701 
1702 static int gfs2_getattr(struct vfsmount *mnt, struct dentry *dentry,
1703 			struct kstat *stat)
1704 {
1705 	struct inode *inode = dentry->d_inode;
1706 	struct gfs2_inode *ip = GFS2_I(inode);
1707 	struct gfs2_holder gh;
1708 	int error;
1709 	int unlock = 0;
1710 
1711 	if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
1712 		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
1713 		if (error)
1714 			return error;
1715 		unlock = 1;
1716 	}
1717 
1718 	generic_fillattr(inode, stat);
1719 	if (unlock)
1720 		gfs2_glock_dq_uninit(&gh);
1721 
1722 	return 0;
1723 }
1724 
1725 static int gfs2_setxattr(struct dentry *dentry, const char *name,
1726 			 const void *data, size_t size, int flags)
1727 {
1728 	struct inode *inode = dentry->d_inode;
1729 	struct gfs2_inode *ip = GFS2_I(inode);
1730 	struct gfs2_holder gh;
1731 	int ret;
1732 
1733 	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
1734 	ret = gfs2_glock_nq(&gh);
1735 	if (ret == 0) {
1736 		ret = gfs2_rs_alloc(ip);
1737 		if (ret == 0)
1738 			ret = generic_setxattr(dentry, name, data, size, flags);
1739 		gfs2_glock_dq(&gh);
1740 	}
1741 	gfs2_holder_uninit(&gh);
1742 	return ret;
1743 }
1744 
1745 static ssize_t gfs2_getxattr(struct dentry *dentry, const char *name,
1746 			     void *data, size_t size)
1747 {
1748 	struct inode *inode = dentry->d_inode;
1749 	struct gfs2_inode *ip = GFS2_I(inode);
1750 	struct gfs2_holder gh;
1751 	int ret;
1752 
1753 	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
1754 	ret = gfs2_glock_nq(&gh);
1755 	if (ret == 0) {
1756 		ret = generic_getxattr(dentry, name, data, size);
1757 		gfs2_glock_dq(&gh);
1758 	}
1759 	gfs2_holder_uninit(&gh);
1760 	return ret;
1761 }
1762 
1763 static int gfs2_removexattr(struct dentry *dentry, const char *name)
1764 {
1765 	struct inode *inode = dentry->d_inode;
1766 	struct gfs2_inode *ip = GFS2_I(inode);
1767 	struct gfs2_holder gh;
1768 	int ret;
1769 
1770 	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
1771 	ret = gfs2_glock_nq(&gh);
1772 	if (ret == 0) {
1773 		ret = gfs2_rs_alloc(ip);
1774 		if (ret == 0)
1775 			ret = generic_removexattr(dentry, name);
1776 		gfs2_glock_dq(&gh);
1777 	}
1778 	gfs2_holder_uninit(&gh);
1779 	return ret;
1780 }
1781 
1782 static int gfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
1783 		       u64 start, u64 len)
1784 {
1785 	struct gfs2_inode *ip = GFS2_I(inode);
1786 	struct gfs2_holder gh;
1787 	int ret;
1788 
1789 	ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC);
1790 	if (ret)
1791 		return ret;
1792 
1793 	mutex_lock(&inode->i_mutex);
1794 
1795 	ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
1796 	if (ret)
1797 		goto out;
1798 
1799 	if (gfs2_is_stuffed(ip)) {
1800 		u64 phys = ip->i_no_addr << inode->i_blkbits;
1801 		u64 size = i_size_read(inode);
1802 		u32 flags = FIEMAP_EXTENT_LAST|FIEMAP_EXTENT_NOT_ALIGNED|
1803 			    FIEMAP_EXTENT_DATA_INLINE;
1804 		phys += sizeof(struct gfs2_dinode);
1805 		phys += start;
1806 		if (start + len > size)
1807 			len = size - start;
1808 		if (start < size)
1809 			ret = fiemap_fill_next_extent(fieinfo, start, phys,
1810 						      len, flags);
1811 		if (ret == 1)
1812 			ret = 0;
1813 	} else {
1814 		ret = __generic_block_fiemap(inode, fieinfo, start, len,
1815 					     gfs2_block_map);
1816 	}
1817 
1818 	gfs2_glock_dq_uninit(&gh);
1819 out:
1820 	mutex_unlock(&inode->i_mutex);
1821 	return ret;
1822 }
1823 
1824 const struct inode_operations gfs2_file_iops = {
1825 	.permission = gfs2_permission,
1826 	.setattr = gfs2_setattr,
1827 	.getattr = gfs2_getattr,
1828 	.setxattr = gfs2_setxattr,
1829 	.getxattr = gfs2_getxattr,
1830 	.listxattr = gfs2_listxattr,
1831 	.removexattr = gfs2_removexattr,
1832 	.fiemap = gfs2_fiemap,
1833 	.get_acl = gfs2_get_acl,
1834 };
1835 
1836 const struct inode_operations gfs2_dir_iops = {
1837 	.create = gfs2_create,
1838 	.lookup = gfs2_lookup,
1839 	.link = gfs2_link,
1840 	.unlink = gfs2_unlink,
1841 	.symlink = gfs2_symlink,
1842 	.mkdir = gfs2_mkdir,
1843 	.rmdir = gfs2_unlink,
1844 	.mknod = gfs2_mknod,
1845 	.rename = gfs2_rename,
1846 	.permission = gfs2_permission,
1847 	.setattr = gfs2_setattr,
1848 	.getattr = gfs2_getattr,
1849 	.setxattr = gfs2_setxattr,
1850 	.getxattr = gfs2_getxattr,
1851 	.listxattr = gfs2_listxattr,
1852 	.removexattr = gfs2_removexattr,
1853 	.fiemap = gfs2_fiemap,
1854 	.get_acl = gfs2_get_acl,
1855 	.atomic_open = gfs2_atomic_open,
1856 };
1857 
1858 const struct inode_operations gfs2_symlink_iops = {
1859 	.readlink = generic_readlink,
1860 	.follow_link = gfs2_follow_link,
1861 	.put_link = gfs2_put_link,
1862 	.permission = gfs2_permission,
1863 	.setattr = gfs2_setattr,
1864 	.getattr = gfs2_getattr,
1865 	.setxattr = gfs2_setxattr,
1866 	.getxattr = gfs2_getxattr,
1867 	.listxattr = gfs2_listxattr,
1868 	.removexattr = gfs2_removexattr,
1869 	.fiemap = gfs2_fiemap,
1870 	.get_acl = gfs2_get_acl,
1871 };
1872 
1873