xref: /openbmc/linux/fs/gfs2/inode.c (revision 0d0d1107)
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) {
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 		return error;
597 	} else if (error != -ENOENT) {
598 		goto fail_gunlock;
599 	}
600 
601 	arq = error = gfs2_diradd_alloc_required(dir, name);
602 	if (error < 0)
603 		goto fail_gunlock;
604 
605 	inode = new_inode(sdp->sd_vfs);
606 	error = -ENOMEM;
607 	if (!inode)
608 		goto fail_gunlock;
609 
610 	ip = GFS2_I(inode);
611 	error = gfs2_rs_alloc(ip);
612 	if (error)
613 		goto fail_free_inode;
614 
615 	inode->i_mode = mode;
616 	set_nlink(inode, S_ISDIR(mode) ? 2 : 1);
617 	inode->i_rdev = dev;
618 	inode->i_size = size;
619 	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
620 	gfs2_set_inode_blocks(inode, 1);
621 	munge_mode_uid_gid(dip, inode);
622 	ip->i_goal = dip->i_goal;
623 	ip->i_diskflags = 0;
624 	ip->i_eattr = 0;
625 	ip->i_height = 0;
626 	ip->i_depth = 0;
627 	ip->i_entries = 0;
628 
629 	switch(mode & S_IFMT) {
630 	case S_IFREG:
631 		if ((dip->i_diskflags & GFS2_DIF_INHERIT_JDATA) ||
632 		    gfs2_tune_get(sdp, gt_new_files_jdata))
633 			ip->i_diskflags |= GFS2_DIF_JDATA;
634 		gfs2_set_aops(inode);
635 		break;
636 	case S_IFDIR:
637 		ip->i_diskflags |= (dip->i_diskflags & GFS2_DIF_INHERIT_JDATA);
638 		ip->i_diskflags |= GFS2_DIF_JDATA;
639 		ip->i_entries = 2;
640 		break;
641 	}
642 	gfs2_set_inode_flags(inode);
643 
644 	if ((GFS2_I(sdp->sd_root_dir->d_inode) == dip) ||
645 	    (dip->i_diskflags & GFS2_DIF_TOPDIR))
646 		aflags |= GFS2_AF_ORLOV;
647 
648 	error = alloc_dinode(ip, aflags);
649 	if (error)
650 		goto fail_free_inode;
651 
652 	error = gfs2_glock_get(sdp, ip->i_no_addr, &gfs2_inode_glops, CREATE, &ip->i_gl);
653 	if (error)
654 		goto fail_free_inode;
655 
656 	ip->i_gl->gl_object = ip;
657 	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, ghs + 1);
658 	if (error)
659 		goto fail_free_inode;
660 
661 	error = gfs2_trans_begin(sdp, RES_DINODE, 0);
662 	if (error)
663 		goto fail_gunlock2;
664 
665 	init_dinode(dip, ip, symname);
666 	gfs2_trans_end(sdp);
667 
668 	error = gfs2_glock_get(sdp, ip->i_no_addr, &gfs2_iopen_glops, CREATE, &io_gl);
669 	if (error)
670 		goto fail_gunlock2;
671 
672 	error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED, GL_EXACT, &ip->i_iopen_gh);
673 	if (error)
674 		goto fail_gunlock2;
675 
676 	ip->i_iopen_gh.gh_gl->gl_object = ip;
677 	gfs2_glock_put(io_gl);
678 	gfs2_set_iop(inode);
679 	insert_inode_hash(inode);
680 
681 	error = gfs2_acl_create(dip, inode);
682 	if (error)
683 		goto fail_gunlock3;
684 
685 	error = gfs2_security_init(dip, ip, name);
686 	if (error)
687 		goto fail_gunlock3;
688 
689 	error = link_dinode(dip, name, ip, arq);
690 	if (error)
691 		goto fail_gunlock3;
692 
693 	mark_inode_dirty(inode);
694 	d_instantiate(dentry, inode);
695 	if (file)
696 		error = finish_open(file, dentry, gfs2_open_common, opened);
697 	gfs2_glock_dq_uninit(ghs);
698 	gfs2_glock_dq_uninit(ghs + 1);
699 	return error;
700 
701 fail_gunlock3:
702 	gfs2_glock_dq_uninit(ghs + 1);
703 	if (ip->i_gl)
704 		gfs2_glock_put(ip->i_gl);
705 	goto fail_gunlock;
706 
707 fail_gunlock2:
708 	gfs2_glock_dq_uninit(ghs + 1);
709 fail_free_inode:
710 	if (ip->i_gl)
711 		gfs2_glock_put(ip->i_gl);
712 	gfs2_rs_delete(ip);
713 	free_inode_nonrcu(inode);
714 	inode = NULL;
715 fail_gunlock:
716 	gfs2_glock_dq_uninit(ghs);
717 	if (inode && !IS_ERR(inode)) {
718 		clear_nlink(inode);
719 		mark_inode_dirty(inode);
720 		set_bit(GIF_ALLOC_FAILED, &GFS2_I(inode)->i_flags);
721 		iput(inode);
722 	}
723 fail:
724 	return error;
725 }
726 
727 /**
728  * gfs2_create - Create a file
729  * @dir: The directory in which to create the file
730  * @dentry: The dentry of the new file
731  * @mode: The mode of the new file
732  *
733  * Returns: errno
734  */
735 
736 static int gfs2_create(struct inode *dir, struct dentry *dentry,
737 		       umode_t mode, bool excl)
738 {
739 	return gfs2_create_inode(dir, dentry, NULL, S_IFREG | mode, 0, NULL, 0, excl, NULL);
740 }
741 
742 /**
743  * __gfs2_lookup - Look up a filename in a directory and return its inode
744  * @dir: The directory inode
745  * @dentry: The dentry of the new inode
746  * @file: File to be opened
747  * @opened: atomic_open flags
748  *
749  *
750  * Returns: errno
751  */
752 
753 static struct dentry *__gfs2_lookup(struct inode *dir, struct dentry *dentry,
754 				    struct file *file, int *opened)
755 {
756 	struct inode *inode;
757 	struct dentry *d;
758 	struct gfs2_holder gh;
759 	struct gfs2_glock *gl;
760 	int error;
761 
762 	inode = gfs2_lookupi(dir, &dentry->d_name, 0);
763 	if (!inode)
764 		return NULL;
765 	if (IS_ERR(inode))
766 		return ERR_CAST(inode);
767 
768 	gl = GFS2_I(inode)->i_gl;
769 	error = gfs2_glock_nq_init(gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
770 	if (error) {
771 		iput(inode);
772 		return ERR_PTR(error);
773 	}
774 
775 	d = d_splice_alias(inode, dentry);
776 	if (file && S_ISREG(inode->i_mode))
777 		error = finish_open(file, dentry, gfs2_open_common, opened);
778 
779 	gfs2_glock_dq_uninit(&gh);
780 	if (error)
781 		return ERR_PTR(error);
782 	return d;
783 }
784 
785 static struct dentry *gfs2_lookup(struct inode *dir, struct dentry *dentry,
786 				  unsigned flags)
787 {
788 	return __gfs2_lookup(dir, dentry, NULL, NULL);
789 }
790 
791 /**
792  * gfs2_link - Link to a file
793  * @old_dentry: The inode to link
794  * @dir: Add link to this directory
795  * @dentry: The name of the link
796  *
797  * Link the inode in "old_dentry" into the directory "dir" with the
798  * name in "dentry".
799  *
800  * Returns: errno
801  */
802 
803 static int gfs2_link(struct dentry *old_dentry, struct inode *dir,
804 		     struct dentry *dentry)
805 {
806 	struct gfs2_inode *dip = GFS2_I(dir);
807 	struct gfs2_sbd *sdp = GFS2_SB(dir);
808 	struct inode *inode = old_dentry->d_inode;
809 	struct gfs2_inode *ip = GFS2_I(inode);
810 	struct gfs2_holder ghs[2];
811 	struct buffer_head *dibh;
812 	int alloc_required;
813 	int error;
814 
815 	if (S_ISDIR(inode->i_mode))
816 		return -EPERM;
817 
818 	error = gfs2_rs_alloc(dip);
819 	if (error)
820 		return error;
821 
822 	gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
823 	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + 1);
824 
825 	error = gfs2_glock_nq(ghs); /* parent */
826 	if (error)
827 		goto out_parent;
828 
829 	error = gfs2_glock_nq(ghs + 1); /* child */
830 	if (error)
831 		goto out_child;
832 
833 	error = -ENOENT;
834 	if (inode->i_nlink == 0)
835 		goto out_gunlock;
836 
837 	error = gfs2_permission(dir, MAY_WRITE | MAY_EXEC);
838 	if (error)
839 		goto out_gunlock;
840 
841 	error = gfs2_dir_check(dir, &dentry->d_name, NULL);
842 	switch (error) {
843 	case -ENOENT:
844 		break;
845 	case 0:
846 		error = -EEXIST;
847 	default:
848 		goto out_gunlock;
849 	}
850 
851 	error = -EINVAL;
852 	if (!dip->i_inode.i_nlink)
853 		goto out_gunlock;
854 	error = -EFBIG;
855 	if (dip->i_entries == (u32)-1)
856 		goto out_gunlock;
857 	error = -EPERM;
858 	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
859 		goto out_gunlock;
860 	error = -EINVAL;
861 	if (!ip->i_inode.i_nlink)
862 		goto out_gunlock;
863 	error = -EMLINK;
864 	if (ip->i_inode.i_nlink == (u32)-1)
865 		goto out_gunlock;
866 
867 	alloc_required = error = gfs2_diradd_alloc_required(dir, &dentry->d_name);
868 	if (error < 0)
869 		goto out_gunlock;
870 	error = 0;
871 
872 	if (alloc_required) {
873 		error = gfs2_quota_lock_check(dip);
874 		if (error)
875 			goto out_gunlock;
876 
877 		error = gfs2_inplace_reserve(dip, sdp->sd_max_dirres, 0);
878 		if (error)
879 			goto out_gunlock_q;
880 
881 		error = gfs2_trans_begin(sdp, sdp->sd_max_dirres +
882 					 gfs2_rg_blocks(dip, sdp->sd_max_dirres) +
883 					 2 * RES_DINODE + RES_STATFS +
884 					 RES_QUOTA, 0);
885 		if (error)
886 			goto out_ipres;
887 	} else {
888 		error = gfs2_trans_begin(sdp, 2 * RES_DINODE + RES_LEAF, 0);
889 		if (error)
890 			goto out_ipres;
891 	}
892 
893 	error = gfs2_meta_inode_buffer(ip, &dibh);
894 	if (error)
895 		goto out_end_trans;
896 
897 	error = gfs2_dir_add(dir, &dentry->d_name, ip);
898 	if (error)
899 		goto out_brelse;
900 
901 	gfs2_trans_add_meta(ip->i_gl, dibh);
902 	inc_nlink(&ip->i_inode);
903 	ip->i_inode.i_ctime = CURRENT_TIME;
904 	ihold(inode);
905 	d_instantiate(dentry, inode);
906 	mark_inode_dirty(inode);
907 
908 out_brelse:
909 	brelse(dibh);
910 out_end_trans:
911 	gfs2_trans_end(sdp);
912 out_ipres:
913 	if (alloc_required)
914 		gfs2_inplace_release(dip);
915 out_gunlock_q:
916 	if (alloc_required)
917 		gfs2_quota_unlock(dip);
918 out_gunlock:
919 	gfs2_glock_dq(ghs + 1);
920 out_child:
921 	gfs2_glock_dq(ghs);
922 out_parent:
923 	gfs2_holder_uninit(ghs);
924 	gfs2_holder_uninit(ghs + 1);
925 	return error;
926 }
927 
928 /*
929  * gfs2_unlink_ok - check to see that a inode is still in a directory
930  * @dip: the directory
931  * @name: the name of the file
932  * @ip: the inode
933  *
934  * Assumes that the lock on (at least) @dip is held.
935  *
936  * Returns: 0 if the parent/child relationship is correct, errno if it isn't
937  */
938 
939 static int gfs2_unlink_ok(struct gfs2_inode *dip, const struct qstr *name,
940 			  const struct gfs2_inode *ip)
941 {
942 	int error;
943 
944 	if (IS_IMMUTABLE(&ip->i_inode) || IS_APPEND(&ip->i_inode))
945 		return -EPERM;
946 
947 	if ((dip->i_inode.i_mode & S_ISVTX) &&
948 	    !uid_eq(dip->i_inode.i_uid, current_fsuid()) &&
949 	    !uid_eq(ip->i_inode.i_uid, current_fsuid()) && !capable(CAP_FOWNER))
950 		return -EPERM;
951 
952 	if (IS_APPEND(&dip->i_inode))
953 		return -EPERM;
954 
955 	error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC);
956 	if (error)
957 		return error;
958 
959 	error = gfs2_dir_check(&dip->i_inode, name, ip);
960 	if (error)
961 		return error;
962 
963 	return 0;
964 }
965 
966 /**
967  * gfs2_unlink_inode - Removes an inode from its parent dir and unlinks it
968  * @dip: The parent directory
969  * @name: The name of the entry in the parent directory
970  * @inode: The inode to be removed
971  *
972  * Called with all the locks and in a transaction. This will only be
973  * called for a directory after it has been checked to ensure it is empty.
974  *
975  * Returns: 0 on success, or an error
976  */
977 
978 static int gfs2_unlink_inode(struct gfs2_inode *dip,
979 			     const struct dentry *dentry)
980 {
981 	struct inode *inode = dentry->d_inode;
982 	struct gfs2_inode *ip = GFS2_I(inode);
983 	int error;
984 
985 	error = gfs2_dir_del(dip, dentry);
986 	if (error)
987 		return error;
988 
989 	ip->i_entries = 0;
990 	inode->i_ctime = CURRENT_TIME;
991 	if (S_ISDIR(inode->i_mode))
992 		clear_nlink(inode);
993 	else
994 		drop_nlink(inode);
995 	mark_inode_dirty(inode);
996 	if (inode->i_nlink == 0)
997 		gfs2_unlink_di(inode);
998 	return 0;
999 }
1000 
1001 
1002 /**
1003  * gfs2_unlink - Unlink an inode (this does rmdir as well)
1004  * @dir: The inode of the directory containing the inode to unlink
1005  * @dentry: The file itself
1006  *
1007  * This routine uses the type of the inode as a flag to figure out
1008  * whether this is an unlink or an rmdir.
1009  *
1010  * Returns: errno
1011  */
1012 
1013 static int gfs2_unlink(struct inode *dir, struct dentry *dentry)
1014 {
1015 	struct gfs2_inode *dip = GFS2_I(dir);
1016 	struct gfs2_sbd *sdp = GFS2_SB(dir);
1017 	struct inode *inode = dentry->d_inode;
1018 	struct gfs2_inode *ip = GFS2_I(inode);
1019 	struct gfs2_holder ghs[3];
1020 	struct gfs2_rgrpd *rgd;
1021 	int error;
1022 
1023 	error = gfs2_rindex_update(sdp);
1024 	if (error)
1025 		return error;
1026 
1027 	error = -EROFS;
1028 
1029 	gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
1030 	gfs2_holder_init(ip->i_gl,  LM_ST_EXCLUSIVE, 0, ghs + 1);
1031 
1032 	rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr, 1);
1033 	if (!rgd)
1034 		goto out_inodes;
1035 
1036 	gfs2_holder_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, ghs + 2);
1037 
1038 
1039 	error = gfs2_glock_nq(ghs); /* parent */
1040 	if (error)
1041 		goto out_parent;
1042 
1043 	error = gfs2_glock_nq(ghs + 1); /* child */
1044 	if (error)
1045 		goto out_child;
1046 
1047 	error = -ENOENT;
1048 	if (inode->i_nlink == 0)
1049 		goto out_rgrp;
1050 
1051 	if (S_ISDIR(inode->i_mode)) {
1052 		error = -ENOTEMPTY;
1053 		if (ip->i_entries > 2 || inode->i_nlink > 2)
1054 			goto out_rgrp;
1055 	}
1056 
1057 	error = gfs2_glock_nq(ghs + 2); /* rgrp */
1058 	if (error)
1059 		goto out_rgrp;
1060 
1061 	error = gfs2_unlink_ok(dip, &dentry->d_name, ip);
1062 	if (error)
1063 		goto out_gunlock;
1064 
1065 	error = gfs2_trans_begin(sdp, 2*RES_DINODE + 3*RES_LEAF + RES_RG_BIT, 0);
1066 	if (error)
1067 		goto out_end_trans;
1068 
1069 	error = gfs2_unlink_inode(dip, dentry);
1070 
1071 out_end_trans:
1072 	gfs2_trans_end(sdp);
1073 out_gunlock:
1074 	gfs2_glock_dq(ghs + 2);
1075 out_rgrp:
1076 	gfs2_glock_dq(ghs + 1);
1077 out_child:
1078 	gfs2_glock_dq(ghs);
1079 out_parent:
1080 	gfs2_holder_uninit(ghs + 2);
1081 out_inodes:
1082 	gfs2_holder_uninit(ghs + 1);
1083 	gfs2_holder_uninit(ghs);
1084 	return error;
1085 }
1086 
1087 /**
1088  * gfs2_symlink - Create a symlink
1089  * @dir: The directory to create the symlink in
1090  * @dentry: The dentry to put the symlink in
1091  * @symname: The thing which the link points to
1092  *
1093  * Returns: errno
1094  */
1095 
1096 static int gfs2_symlink(struct inode *dir, struct dentry *dentry,
1097 			const char *symname)
1098 {
1099 	struct gfs2_sbd *sdp = GFS2_SB(dir);
1100 	unsigned int size;
1101 
1102 	size = strlen(symname);
1103 	if (size > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode) - 1)
1104 		return -ENAMETOOLONG;
1105 
1106 	return gfs2_create_inode(dir, dentry, NULL, S_IFLNK | S_IRWXUGO, 0, symname, size, 0, NULL);
1107 }
1108 
1109 /**
1110  * gfs2_mkdir - Make a directory
1111  * @dir: The parent directory of the new one
1112  * @dentry: The dentry of the new directory
1113  * @mode: The mode of the new directory
1114  *
1115  * Returns: errno
1116  */
1117 
1118 static int gfs2_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
1119 {
1120 	struct gfs2_sbd *sdp = GFS2_SB(dir);
1121 	unsigned dsize = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode);
1122 	return gfs2_create_inode(dir, dentry, NULL, S_IFDIR | mode, 0, NULL, dsize, 0, NULL);
1123 }
1124 
1125 /**
1126  * gfs2_mknod - Make a special file
1127  * @dir: The directory in which the special file will reside
1128  * @dentry: The dentry of the special file
1129  * @mode: The mode of the special file
1130  * @dev: The device specification of the special file
1131  *
1132  */
1133 
1134 static int gfs2_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
1135 		      dev_t dev)
1136 {
1137 	return gfs2_create_inode(dir, dentry, NULL, mode, dev, NULL, 0, 0, NULL);
1138 }
1139 
1140 /**
1141  * gfs2_atomic_open - Atomically open a file
1142  * @dir: The directory
1143  * @dentry: The proposed new entry
1144  * @file: The proposed new struct file
1145  * @flags: open flags
1146  * @mode: File mode
1147  * @opened: Flag to say whether the file has been opened or not
1148  *
1149  * Returns: error code or 0 for success
1150  */
1151 
1152 static int gfs2_atomic_open(struct inode *dir, struct dentry *dentry,
1153                             struct file *file, unsigned flags,
1154                             umode_t mode, int *opened)
1155 {
1156 	struct dentry *d;
1157 	bool excl = !!(flags & O_EXCL);
1158 
1159 	d = __gfs2_lookup(dir, dentry, file, opened);
1160 	if (IS_ERR(d))
1161 		return PTR_ERR(d);
1162 	if (d == NULL)
1163 		d = dentry;
1164 	if (d->d_inode) {
1165 		if (!(*opened & FILE_OPENED))
1166 			return finish_no_open(file, d);
1167 		return 0;
1168 	}
1169 
1170 	if (!(flags & O_CREAT))
1171 		return -ENOENT;
1172 
1173 	return gfs2_create_inode(dir, dentry, file, S_IFREG | mode, 0, NULL, 0, excl, opened);
1174 }
1175 
1176 /*
1177  * gfs2_ok_to_move - check if it's ok to move a directory to another directory
1178  * @this: move this
1179  * @to: to here
1180  *
1181  * Follow @to back to the root and make sure we don't encounter @this
1182  * Assumes we already hold the rename lock.
1183  *
1184  * Returns: errno
1185  */
1186 
1187 static int gfs2_ok_to_move(struct gfs2_inode *this, struct gfs2_inode *to)
1188 {
1189 	struct inode *dir = &to->i_inode;
1190 	struct super_block *sb = dir->i_sb;
1191 	struct inode *tmp;
1192 	int error = 0;
1193 
1194 	igrab(dir);
1195 
1196 	for (;;) {
1197 		if (dir == &this->i_inode) {
1198 			error = -EINVAL;
1199 			break;
1200 		}
1201 		if (dir == sb->s_root->d_inode) {
1202 			error = 0;
1203 			break;
1204 		}
1205 
1206 		tmp = gfs2_lookupi(dir, &gfs2_qdotdot, 1);
1207 		if (IS_ERR(tmp)) {
1208 			error = PTR_ERR(tmp);
1209 			break;
1210 		}
1211 
1212 		iput(dir);
1213 		dir = tmp;
1214 	}
1215 
1216 	iput(dir);
1217 
1218 	return error;
1219 }
1220 
1221 /**
1222  * gfs2_rename - Rename a file
1223  * @odir: Parent directory of old file name
1224  * @odentry: The old dentry of the file
1225  * @ndir: Parent directory of new file name
1226  * @ndentry: The new dentry of the file
1227  *
1228  * Returns: errno
1229  */
1230 
1231 static int gfs2_rename(struct inode *odir, struct dentry *odentry,
1232 		       struct inode *ndir, struct dentry *ndentry)
1233 {
1234 	struct gfs2_inode *odip = GFS2_I(odir);
1235 	struct gfs2_inode *ndip = GFS2_I(ndir);
1236 	struct gfs2_inode *ip = GFS2_I(odentry->d_inode);
1237 	struct gfs2_inode *nip = NULL;
1238 	struct gfs2_sbd *sdp = GFS2_SB(odir);
1239 	struct gfs2_holder ghs[5], r_gh = { .gh_gl = NULL, };
1240 	struct gfs2_rgrpd *nrgd;
1241 	unsigned int num_gh;
1242 	int dir_rename = 0;
1243 	int alloc_required = 0;
1244 	unsigned int x;
1245 	int error;
1246 
1247 	if (ndentry->d_inode) {
1248 		nip = GFS2_I(ndentry->d_inode);
1249 		if (ip == nip)
1250 			return 0;
1251 	}
1252 
1253 	error = gfs2_rindex_update(sdp);
1254 	if (error)
1255 		return error;
1256 
1257 	error = gfs2_rs_alloc(ndip);
1258 	if (error)
1259 		return error;
1260 
1261 	if (odip != ndip) {
1262 		error = gfs2_glock_nq_init(sdp->sd_rename_gl, LM_ST_EXCLUSIVE,
1263 					   0, &r_gh);
1264 		if (error)
1265 			goto out;
1266 
1267 		if (S_ISDIR(ip->i_inode.i_mode)) {
1268 			dir_rename = 1;
1269 			/* don't move a dirctory into it's subdir */
1270 			error = gfs2_ok_to_move(ip, ndip);
1271 			if (error)
1272 				goto out_gunlock_r;
1273 		}
1274 	}
1275 
1276 	num_gh = 1;
1277 	gfs2_holder_init(odip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
1278 	if (odip != ndip) {
1279 		gfs2_holder_init(ndip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
1280 		num_gh++;
1281 	}
1282 	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
1283 	num_gh++;
1284 
1285 	if (nip) {
1286 		gfs2_holder_init(nip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
1287 		num_gh++;
1288 		/* grab the resource lock for unlink flag twiddling
1289 		 * this is the case of the target file already existing
1290 		 * so we unlink before doing the rename
1291 		 */
1292 		nrgd = gfs2_blk2rgrpd(sdp, nip->i_no_addr, 1);
1293 		if (nrgd)
1294 			gfs2_holder_init(nrgd->rd_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh++);
1295 	}
1296 
1297 	for (x = 0; x < num_gh; x++) {
1298 		error = gfs2_glock_nq(ghs + x);
1299 		if (error)
1300 			goto out_gunlock;
1301 	}
1302 
1303 	error = -ENOENT;
1304 	if (ip->i_inode.i_nlink == 0)
1305 		goto out_gunlock;
1306 
1307 	/* Check out the old directory */
1308 
1309 	error = gfs2_unlink_ok(odip, &odentry->d_name, ip);
1310 	if (error)
1311 		goto out_gunlock;
1312 
1313 	/* Check out the new directory */
1314 
1315 	if (nip) {
1316 		error = gfs2_unlink_ok(ndip, &ndentry->d_name, nip);
1317 		if (error)
1318 			goto out_gunlock;
1319 
1320 		if (nip->i_inode.i_nlink == 0) {
1321 			error = -EAGAIN;
1322 			goto out_gunlock;
1323 		}
1324 
1325 		if (S_ISDIR(nip->i_inode.i_mode)) {
1326 			if (nip->i_entries < 2) {
1327 				gfs2_consist_inode(nip);
1328 				error = -EIO;
1329 				goto out_gunlock;
1330 			}
1331 			if (nip->i_entries > 2) {
1332 				error = -ENOTEMPTY;
1333 				goto out_gunlock;
1334 			}
1335 		}
1336 	} else {
1337 		error = gfs2_permission(ndir, MAY_WRITE | MAY_EXEC);
1338 		if (error)
1339 			goto out_gunlock;
1340 
1341 		error = gfs2_dir_check(ndir, &ndentry->d_name, NULL);
1342 		switch (error) {
1343 		case -ENOENT:
1344 			error = 0;
1345 			break;
1346 		case 0:
1347 			error = -EEXIST;
1348 		default:
1349 			goto out_gunlock;
1350 		};
1351 
1352 		if (odip != ndip) {
1353 			if (!ndip->i_inode.i_nlink) {
1354 				error = -ENOENT;
1355 				goto out_gunlock;
1356 			}
1357 			if (ndip->i_entries == (u32)-1) {
1358 				error = -EFBIG;
1359 				goto out_gunlock;
1360 			}
1361 			if (S_ISDIR(ip->i_inode.i_mode) &&
1362 			    ndip->i_inode.i_nlink == (u32)-1) {
1363 				error = -EMLINK;
1364 				goto out_gunlock;
1365 			}
1366 		}
1367 	}
1368 
1369 	/* Check out the dir to be renamed */
1370 
1371 	if (dir_rename) {
1372 		error = gfs2_permission(odentry->d_inode, MAY_WRITE);
1373 		if (error)
1374 			goto out_gunlock;
1375 	}
1376 
1377 	if (nip == NULL)
1378 		alloc_required = gfs2_diradd_alloc_required(ndir, &ndentry->d_name);
1379 	error = alloc_required;
1380 	if (error < 0)
1381 		goto out_gunlock;
1382 
1383 	if (alloc_required) {
1384 		error = gfs2_quota_lock_check(ndip);
1385 		if (error)
1386 			goto out_gunlock;
1387 
1388 		error = gfs2_inplace_reserve(ndip, sdp->sd_max_dirres, 0);
1389 		if (error)
1390 			goto out_gunlock_q;
1391 
1392 		error = gfs2_trans_begin(sdp, sdp->sd_max_dirres +
1393 					 gfs2_rg_blocks(ndip, sdp->sd_max_dirres) +
1394 					 4 * RES_DINODE + 4 * RES_LEAF +
1395 					 RES_STATFS + RES_QUOTA + 4, 0);
1396 		if (error)
1397 			goto out_ipreserv;
1398 	} else {
1399 		error = gfs2_trans_begin(sdp, 4 * RES_DINODE +
1400 					 5 * RES_LEAF + 4, 0);
1401 		if (error)
1402 			goto out_gunlock;
1403 	}
1404 
1405 	/* Remove the target file, if it exists */
1406 
1407 	if (nip)
1408 		error = gfs2_unlink_inode(ndip, ndentry);
1409 
1410 	if (dir_rename) {
1411 		error = gfs2_dir_mvino(ip, &gfs2_qdotdot, ndip, DT_DIR);
1412 		if (error)
1413 			goto out_end_trans;
1414 	} else {
1415 		struct buffer_head *dibh;
1416 		error = gfs2_meta_inode_buffer(ip, &dibh);
1417 		if (error)
1418 			goto out_end_trans;
1419 		ip->i_inode.i_ctime = CURRENT_TIME;
1420 		gfs2_trans_add_meta(ip->i_gl, dibh);
1421 		gfs2_dinode_out(ip, dibh->b_data);
1422 		brelse(dibh);
1423 	}
1424 
1425 	error = gfs2_dir_del(odip, odentry);
1426 	if (error)
1427 		goto out_end_trans;
1428 
1429 	error = gfs2_dir_add(ndir, &ndentry->d_name, ip);
1430 	if (error)
1431 		goto out_end_trans;
1432 
1433 out_end_trans:
1434 	gfs2_trans_end(sdp);
1435 out_ipreserv:
1436 	if (alloc_required)
1437 		gfs2_inplace_release(ndip);
1438 out_gunlock_q:
1439 	if (alloc_required)
1440 		gfs2_quota_unlock(ndip);
1441 out_gunlock:
1442 	while (x--) {
1443 		gfs2_glock_dq(ghs + x);
1444 		gfs2_holder_uninit(ghs + x);
1445 	}
1446 out_gunlock_r:
1447 	if (r_gh.gh_gl)
1448 		gfs2_glock_dq_uninit(&r_gh);
1449 out:
1450 	return error;
1451 }
1452 
1453 /**
1454  * gfs2_follow_link - Follow a symbolic link
1455  * @dentry: The dentry of the link
1456  * @nd: Data that we pass to vfs_follow_link()
1457  *
1458  * This can handle symlinks of any size.
1459  *
1460  * Returns: 0 on success or error code
1461  */
1462 
1463 static void *gfs2_follow_link(struct dentry *dentry, struct nameidata *nd)
1464 {
1465 	struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
1466 	struct gfs2_holder i_gh;
1467 	struct buffer_head *dibh;
1468 	unsigned int size;
1469 	char *buf;
1470 	int error;
1471 
1472 	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
1473 	error = gfs2_glock_nq(&i_gh);
1474 	if (error) {
1475 		gfs2_holder_uninit(&i_gh);
1476 		nd_set_link(nd, ERR_PTR(error));
1477 		return NULL;
1478 	}
1479 
1480 	size = (unsigned int)i_size_read(&ip->i_inode);
1481 	if (size == 0) {
1482 		gfs2_consist_inode(ip);
1483 		buf = ERR_PTR(-EIO);
1484 		goto out;
1485 	}
1486 
1487 	error = gfs2_meta_inode_buffer(ip, &dibh);
1488 	if (error) {
1489 		buf = ERR_PTR(error);
1490 		goto out;
1491 	}
1492 
1493 	buf = kzalloc(size + 1, GFP_NOFS);
1494 	if (!buf)
1495 		buf = ERR_PTR(-ENOMEM);
1496 	else
1497 		memcpy(buf, dibh->b_data + sizeof(struct gfs2_dinode), size);
1498 	brelse(dibh);
1499 out:
1500 	gfs2_glock_dq_uninit(&i_gh);
1501 	nd_set_link(nd, buf);
1502 	return NULL;
1503 }
1504 
1505 static void gfs2_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
1506 {
1507 	char *s = nd_get_link(nd);
1508 	if (!IS_ERR(s))
1509 		kfree(s);
1510 }
1511 
1512 /**
1513  * gfs2_permission -
1514  * @inode: The inode
1515  * @mask: The mask to be tested
1516  * @flags: Indicates whether this is an RCU path walk or not
1517  *
1518  * This may be called from the VFS directly, or from within GFS2 with the
1519  * inode locked, so we look to see if the glock is already locked and only
1520  * lock the glock if its not already been done.
1521  *
1522  * Returns: errno
1523  */
1524 
1525 int gfs2_permission(struct inode *inode, int mask)
1526 {
1527 	struct gfs2_inode *ip;
1528 	struct gfs2_holder i_gh;
1529 	int error;
1530 	int unlock = 0;
1531 
1532 
1533 	ip = GFS2_I(inode);
1534 	if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
1535 		if (mask & MAY_NOT_BLOCK)
1536 			return -ECHILD;
1537 		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
1538 		if (error)
1539 			return error;
1540 		unlock = 1;
1541 	}
1542 
1543 	if ((mask & MAY_WRITE) && IS_IMMUTABLE(inode))
1544 		error = -EACCES;
1545 	else
1546 		error = generic_permission(inode, mask);
1547 	if (unlock)
1548 		gfs2_glock_dq_uninit(&i_gh);
1549 
1550 	return error;
1551 }
1552 
1553 static int __gfs2_setattr_simple(struct inode *inode, struct iattr *attr)
1554 {
1555 	setattr_copy(inode, attr);
1556 	mark_inode_dirty(inode);
1557 	return 0;
1558 }
1559 
1560 /**
1561  * gfs2_setattr_simple -
1562  * @ip:
1563  * @attr:
1564  *
1565  * Returns: errno
1566  */
1567 
1568 int gfs2_setattr_simple(struct inode *inode, struct iattr *attr)
1569 {
1570 	int error;
1571 
1572 	if (current->journal_info)
1573 		return __gfs2_setattr_simple(inode, attr);
1574 
1575 	error = gfs2_trans_begin(GFS2_SB(inode), RES_DINODE, 0);
1576 	if (error)
1577 		return error;
1578 
1579 	error = __gfs2_setattr_simple(inode, attr);
1580 	gfs2_trans_end(GFS2_SB(inode));
1581 	return error;
1582 }
1583 
1584 static int setattr_chown(struct inode *inode, struct iattr *attr)
1585 {
1586 	struct gfs2_inode *ip = GFS2_I(inode);
1587 	struct gfs2_sbd *sdp = GFS2_SB(inode);
1588 	kuid_t ouid, nuid;
1589 	kgid_t ogid, ngid;
1590 	int error;
1591 
1592 	ouid = inode->i_uid;
1593 	ogid = inode->i_gid;
1594 	nuid = attr->ia_uid;
1595 	ngid = attr->ia_gid;
1596 
1597 	if (!(attr->ia_valid & ATTR_UID) || uid_eq(ouid, nuid))
1598 		ouid = nuid = NO_UID_QUOTA_CHANGE;
1599 	if (!(attr->ia_valid & ATTR_GID) || gid_eq(ogid, ngid))
1600 		ogid = ngid = NO_GID_QUOTA_CHANGE;
1601 
1602 	error = gfs2_quota_lock(ip, nuid, ngid);
1603 	if (error)
1604 		return error;
1605 
1606 	if (!uid_eq(ouid, NO_UID_QUOTA_CHANGE) ||
1607 	    !gid_eq(ogid, NO_GID_QUOTA_CHANGE)) {
1608 		error = gfs2_quota_check(ip, nuid, ngid);
1609 		if (error)
1610 			goto out_gunlock_q;
1611 	}
1612 
1613 	error = gfs2_trans_begin(sdp, RES_DINODE + 2 * RES_QUOTA, 0);
1614 	if (error)
1615 		goto out_gunlock_q;
1616 
1617 	error = gfs2_setattr_simple(inode, attr);
1618 	if (error)
1619 		goto out_end_trans;
1620 
1621 	if (!uid_eq(ouid, NO_UID_QUOTA_CHANGE) ||
1622 	    !gid_eq(ogid, NO_GID_QUOTA_CHANGE)) {
1623 		u64 blocks = gfs2_get_inode_blocks(&ip->i_inode);
1624 		gfs2_quota_change(ip, -blocks, ouid, ogid);
1625 		gfs2_quota_change(ip, blocks, nuid, ngid);
1626 	}
1627 
1628 out_end_trans:
1629 	gfs2_trans_end(sdp);
1630 out_gunlock_q:
1631 	gfs2_quota_unlock(ip);
1632 	return error;
1633 }
1634 
1635 /**
1636  * gfs2_setattr - Change attributes on an inode
1637  * @dentry: The dentry which is changing
1638  * @attr: The structure describing the change
1639  *
1640  * The VFS layer wants to change one or more of an inodes attributes.  Write
1641  * that change out to disk.
1642  *
1643  * Returns: errno
1644  */
1645 
1646 static int gfs2_setattr(struct dentry *dentry, struct iattr *attr)
1647 {
1648 	struct inode *inode = dentry->d_inode;
1649 	struct gfs2_inode *ip = GFS2_I(inode);
1650 	struct gfs2_holder i_gh;
1651 	int error;
1652 
1653 	error = gfs2_rs_alloc(ip);
1654 	if (error)
1655 		return error;
1656 
1657 	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1658 	if (error)
1659 		return error;
1660 
1661 	error = -EPERM;
1662 	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
1663 		goto out;
1664 
1665 	error = inode_change_ok(inode, attr);
1666 	if (error)
1667 		goto out;
1668 
1669 	if (attr->ia_valid & ATTR_SIZE)
1670 		error = gfs2_setattr_size(inode, attr->ia_size);
1671 	else if (attr->ia_valid & (ATTR_UID | ATTR_GID))
1672 		error = setattr_chown(inode, attr);
1673 	else if ((attr->ia_valid & ATTR_MODE) && IS_POSIXACL(inode))
1674 		error = gfs2_acl_chmod(ip, attr);
1675 	else
1676 		error = gfs2_setattr_simple(inode, attr);
1677 
1678 out:
1679 	if (!error)
1680 		mark_inode_dirty(inode);
1681 	gfs2_glock_dq_uninit(&i_gh);
1682 	return error;
1683 }
1684 
1685 /**
1686  * gfs2_getattr - Read out an inode's attributes
1687  * @mnt: The vfsmount the inode is being accessed from
1688  * @dentry: The dentry to stat
1689  * @stat: The inode's stats
1690  *
1691  * This may be called from the VFS directly, or from within GFS2 with the
1692  * inode locked, so we look to see if the glock is already locked and only
1693  * lock the glock if its not already been done. Note that its the NFS
1694  * readdirplus operation which causes this to be called (from filldir)
1695  * with the glock already held.
1696  *
1697  * Returns: errno
1698  */
1699 
1700 static int gfs2_getattr(struct vfsmount *mnt, struct dentry *dentry,
1701 			struct kstat *stat)
1702 {
1703 	struct inode *inode = dentry->d_inode;
1704 	struct gfs2_inode *ip = GFS2_I(inode);
1705 	struct gfs2_holder gh;
1706 	int error;
1707 	int unlock = 0;
1708 
1709 	if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
1710 		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
1711 		if (error)
1712 			return error;
1713 		unlock = 1;
1714 	}
1715 
1716 	generic_fillattr(inode, stat);
1717 	if (unlock)
1718 		gfs2_glock_dq_uninit(&gh);
1719 
1720 	return 0;
1721 }
1722 
1723 static int gfs2_setxattr(struct dentry *dentry, const char *name,
1724 			 const void *data, size_t size, int flags)
1725 {
1726 	struct inode *inode = dentry->d_inode;
1727 	struct gfs2_inode *ip = GFS2_I(inode);
1728 	struct gfs2_holder gh;
1729 	int ret;
1730 
1731 	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
1732 	ret = gfs2_glock_nq(&gh);
1733 	if (ret == 0) {
1734 		ret = gfs2_rs_alloc(ip);
1735 		if (ret == 0)
1736 			ret = generic_setxattr(dentry, name, data, size, flags);
1737 		gfs2_glock_dq(&gh);
1738 	}
1739 	gfs2_holder_uninit(&gh);
1740 	return ret;
1741 }
1742 
1743 static ssize_t gfs2_getxattr(struct dentry *dentry, const char *name,
1744 			     void *data, size_t size)
1745 {
1746 	struct inode *inode = dentry->d_inode;
1747 	struct gfs2_inode *ip = GFS2_I(inode);
1748 	struct gfs2_holder gh;
1749 	int ret;
1750 
1751 	/* For selinux during lookup */
1752 	if (gfs2_glock_is_locked_by_me(ip->i_gl))
1753 		return generic_getxattr(dentry, name, data, size);
1754 
1755 	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
1756 	ret = gfs2_glock_nq(&gh);
1757 	if (ret == 0) {
1758 		ret = generic_getxattr(dentry, name, data, size);
1759 		gfs2_glock_dq(&gh);
1760 	}
1761 	gfs2_holder_uninit(&gh);
1762 	return ret;
1763 }
1764 
1765 static int gfs2_removexattr(struct dentry *dentry, const char *name)
1766 {
1767 	struct inode *inode = dentry->d_inode;
1768 	struct gfs2_inode *ip = GFS2_I(inode);
1769 	struct gfs2_holder gh;
1770 	int ret;
1771 
1772 	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
1773 	ret = gfs2_glock_nq(&gh);
1774 	if (ret == 0) {
1775 		ret = gfs2_rs_alloc(ip);
1776 		if (ret == 0)
1777 			ret = generic_removexattr(dentry, name);
1778 		gfs2_glock_dq(&gh);
1779 	}
1780 	gfs2_holder_uninit(&gh);
1781 	return ret;
1782 }
1783 
1784 static int gfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
1785 		       u64 start, u64 len)
1786 {
1787 	struct gfs2_inode *ip = GFS2_I(inode);
1788 	struct gfs2_holder gh;
1789 	int ret;
1790 
1791 	ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC);
1792 	if (ret)
1793 		return ret;
1794 
1795 	mutex_lock(&inode->i_mutex);
1796 
1797 	ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
1798 	if (ret)
1799 		goto out;
1800 
1801 	if (gfs2_is_stuffed(ip)) {
1802 		u64 phys = ip->i_no_addr << inode->i_blkbits;
1803 		u64 size = i_size_read(inode);
1804 		u32 flags = FIEMAP_EXTENT_LAST|FIEMAP_EXTENT_NOT_ALIGNED|
1805 			    FIEMAP_EXTENT_DATA_INLINE;
1806 		phys += sizeof(struct gfs2_dinode);
1807 		phys += start;
1808 		if (start + len > size)
1809 			len = size - start;
1810 		if (start < size)
1811 			ret = fiemap_fill_next_extent(fieinfo, start, phys,
1812 						      len, flags);
1813 		if (ret == 1)
1814 			ret = 0;
1815 	} else {
1816 		ret = __generic_block_fiemap(inode, fieinfo, start, len,
1817 					     gfs2_block_map);
1818 	}
1819 
1820 	gfs2_glock_dq_uninit(&gh);
1821 out:
1822 	mutex_unlock(&inode->i_mutex);
1823 	return ret;
1824 }
1825 
1826 const struct inode_operations gfs2_file_iops = {
1827 	.permission = gfs2_permission,
1828 	.setattr = gfs2_setattr,
1829 	.getattr = gfs2_getattr,
1830 	.setxattr = gfs2_setxattr,
1831 	.getxattr = gfs2_getxattr,
1832 	.listxattr = gfs2_listxattr,
1833 	.removexattr = gfs2_removexattr,
1834 	.fiemap = gfs2_fiemap,
1835 	.get_acl = gfs2_get_acl,
1836 };
1837 
1838 const struct inode_operations gfs2_dir_iops = {
1839 	.create = gfs2_create,
1840 	.lookup = gfs2_lookup,
1841 	.link = gfs2_link,
1842 	.unlink = gfs2_unlink,
1843 	.symlink = gfs2_symlink,
1844 	.mkdir = gfs2_mkdir,
1845 	.rmdir = gfs2_unlink,
1846 	.mknod = gfs2_mknod,
1847 	.rename = gfs2_rename,
1848 	.permission = gfs2_permission,
1849 	.setattr = gfs2_setattr,
1850 	.getattr = gfs2_getattr,
1851 	.setxattr = gfs2_setxattr,
1852 	.getxattr = gfs2_getxattr,
1853 	.listxattr = gfs2_listxattr,
1854 	.removexattr = gfs2_removexattr,
1855 	.fiemap = gfs2_fiemap,
1856 	.get_acl = gfs2_get_acl,
1857 	.atomic_open = gfs2_atomic_open,
1858 };
1859 
1860 const struct inode_operations gfs2_symlink_iops = {
1861 	.readlink = generic_readlink,
1862 	.follow_link = gfs2_follow_link,
1863 	.put_link = gfs2_put_link,
1864 	.permission = gfs2_permission,
1865 	.setattr = gfs2_setattr,
1866 	.getattr = gfs2_getattr,
1867 	.setxattr = gfs2_setxattr,
1868 	.getxattr = gfs2_getxattr,
1869 	.listxattr = gfs2_listxattr,
1870 	.removexattr = gfs2_removexattr,
1871 	.fiemap = gfs2_fiemap,
1872 	.get_acl = gfs2_get_acl,
1873 };
1874 
1875