xref: /openbmc/linux/fs/gfs2/inode.c (revision 305c8388)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
4  * Copyright (C) 2004-2011 Red Hat, Inc.  All rights reserved.
5  */
6 
7 #include <linux/slab.h>
8 #include <linux/spinlock.h>
9 #include <linux/completion.h>
10 #include <linux/buffer_head.h>
11 #include <linux/namei.h>
12 #include <linux/mm.h>
13 #include <linux/cred.h>
14 #include <linux/xattr.h>
15 #include <linux/posix_acl.h>
16 #include <linux/gfs2_ondisk.h>
17 #include <linux/crc32.h>
18 #include <linux/iomap.h>
19 #include <linux/security.h>
20 #include <linux/fiemap.h>
21 #include <linux/uaccess.h>
22 
23 #include "gfs2.h"
24 #include "incore.h"
25 #include "acl.h"
26 #include "bmap.h"
27 #include "dir.h"
28 #include "xattr.h"
29 #include "glock.h"
30 #include "inode.h"
31 #include "meta_io.h"
32 #include "quota.h"
33 #include "rgrp.h"
34 #include "trans.h"
35 #include "util.h"
36 #include "super.h"
37 #include "glops.h"
38 
39 static int iget_test(struct inode *inode, void *opaque)
40 {
41 	u64 no_addr = *(u64 *)opaque;
42 
43 	return GFS2_I(inode)->i_no_addr == no_addr;
44 }
45 
46 static int iget_set(struct inode *inode, void *opaque)
47 {
48 	u64 no_addr = *(u64 *)opaque;
49 
50 	GFS2_I(inode)->i_no_addr = no_addr;
51 	inode->i_ino = no_addr;
52 	return 0;
53 }
54 
55 static struct inode *gfs2_iget(struct super_block *sb, u64 no_addr)
56 {
57 	struct inode *inode;
58 
59 repeat:
60 	inode = iget5_locked(sb, no_addr, iget_test, iget_set, &no_addr);
61 	if (!inode)
62 		return inode;
63 	if (is_bad_inode(inode)) {
64 		iput(inode);
65 		goto repeat;
66 	}
67 	return inode;
68 }
69 
70 /**
71  * gfs2_set_iop - Sets inode operations
72  * @inode: The inode with correct i_mode filled in
73  *
74  * GFS2 lookup code fills in vfs inode contents based on info obtained
75  * from directory entry inside gfs2_inode_lookup().
76  */
77 
78 static void gfs2_set_iop(struct inode *inode)
79 {
80 	struct gfs2_sbd *sdp = GFS2_SB(inode);
81 	umode_t mode = inode->i_mode;
82 
83 	if (S_ISREG(mode)) {
84 		inode->i_op = &gfs2_file_iops;
85 		if (gfs2_localflocks(sdp))
86 			inode->i_fop = &gfs2_file_fops_nolock;
87 		else
88 			inode->i_fop = &gfs2_file_fops;
89 	} else if (S_ISDIR(mode)) {
90 		inode->i_op = &gfs2_dir_iops;
91 		if (gfs2_localflocks(sdp))
92 			inode->i_fop = &gfs2_dir_fops_nolock;
93 		else
94 			inode->i_fop = &gfs2_dir_fops;
95 	} else if (S_ISLNK(mode)) {
96 		inode->i_op = &gfs2_symlink_iops;
97 	} else {
98 		inode->i_op = &gfs2_file_iops;
99 		init_special_inode(inode, inode->i_mode, inode->i_rdev);
100 	}
101 }
102 
103 /**
104  * gfs2_inode_lookup - Lookup an inode
105  * @sb: The super block
106  * @type: The type of the inode
107  * @no_addr: The inode number
108  * @no_formal_ino: The inode generation number
109  * @blktype: Requested block type (GFS2_BLKST_DINODE or GFS2_BLKST_UNLINKED;
110  *           GFS2_BLKST_FREE to indicate not to verify)
111  *
112  * If @type is DT_UNKNOWN, the inode type is fetched from disk.
113  *
114  * If @blktype is anything other than GFS2_BLKST_FREE (which is used as a
115  * placeholder because it doesn't otherwise make sense), the on-disk block type
116  * is verified to be @blktype.
117  *
118  * When @no_formal_ino is non-zero, this function will return ERR_PTR(-ESTALE)
119  * if it detects that @no_formal_ino doesn't match the actual inode generation
120  * number.  However, it doesn't always know unless @type is DT_UNKNOWN.
121  *
122  * Returns: A VFS inode, or an error
123  */
124 
125 struct inode *gfs2_inode_lookup(struct super_block *sb, unsigned int type,
126 				u64 no_addr, u64 no_formal_ino,
127 				unsigned int blktype)
128 {
129 	struct inode *inode;
130 	struct gfs2_inode *ip;
131 	struct gfs2_glock *io_gl = NULL;
132 	struct gfs2_holder i_gh;
133 	int error;
134 
135 	gfs2_holder_mark_uninitialized(&i_gh);
136 	inode = gfs2_iget(sb, no_addr);
137 	if (!inode)
138 		return ERR_PTR(-ENOMEM);
139 
140 	ip = GFS2_I(inode);
141 
142 	if (inode->i_state & I_NEW) {
143 		struct gfs2_sbd *sdp = GFS2_SB(inode);
144 
145 		error = gfs2_glock_get(sdp, no_addr, &gfs2_inode_glops, CREATE, &ip->i_gl);
146 		if (unlikely(error))
147 			goto fail;
148 		flush_delayed_work(&ip->i_gl->gl_work);
149 
150 		error = gfs2_glock_get(sdp, no_addr, &gfs2_iopen_glops, CREATE, &io_gl);
151 		if (unlikely(error))
152 			goto fail;
153 
154 		if (type == DT_UNKNOWN || blktype != GFS2_BLKST_FREE) {
155 			/*
156 			 * The GL_SKIP flag indicates to skip reading the inode
157 			 * block.  We read the inode with gfs2_inode_refresh
158 			 * after possibly checking the block type.
159 			 */
160 			error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE,
161 						   GL_SKIP, &i_gh);
162 			if (error)
163 				goto fail;
164 
165 			error = -ESTALE;
166 			if (no_formal_ino &&
167 			    gfs2_inode_already_deleted(ip->i_gl, no_formal_ino))
168 				goto fail;
169 
170 			if (blktype != GFS2_BLKST_FREE) {
171 				error = gfs2_check_blk_type(sdp, no_addr,
172 							    blktype);
173 				if (error)
174 					goto fail;
175 			}
176 		}
177 
178 		glock_set_object(ip->i_gl, ip);
179 		set_bit(GIF_INVALID, &ip->i_flags);
180 		error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED, GL_EXACT, &ip->i_iopen_gh);
181 		if (unlikely(error))
182 			goto fail;
183 		gfs2_cancel_delete_work(ip->i_iopen_gh.gh_gl);
184 		glock_set_object(ip->i_iopen_gh.gh_gl, ip);
185 		gfs2_glock_put(io_gl);
186 		io_gl = NULL;
187 
188 		/* Lowest possible timestamp; will be overwritten in gfs2_dinode_in. */
189 		inode->i_atime.tv_sec = 1LL << (8 * sizeof(inode->i_atime.tv_sec) - 1);
190 		inode->i_atime.tv_nsec = 0;
191 
192 		if (type == DT_UNKNOWN) {
193 			/* Inode glock must be locked already */
194 			error = gfs2_inode_refresh(GFS2_I(inode));
195 			if (error)
196 				goto fail;
197 		} else {
198 			ip->i_no_formal_ino = no_formal_ino;
199 			inode->i_mode = DT2IF(type);
200 		}
201 
202 		if (gfs2_holder_initialized(&i_gh))
203 			gfs2_glock_dq_uninit(&i_gh);
204 
205 		gfs2_set_iop(inode);
206 	}
207 
208 	if (no_formal_ino && ip->i_no_formal_ino &&
209 	    no_formal_ino != ip->i_no_formal_ino) {
210 		if (inode->i_state & I_NEW)
211 			goto fail;
212 		iput(inode);
213 		return ERR_PTR(-ESTALE);
214 	}
215 
216 	if (inode->i_state & I_NEW)
217 		unlock_new_inode(inode);
218 
219 	return inode;
220 
221 fail:
222 	if (io_gl)
223 		gfs2_glock_put(io_gl);
224 	if (gfs2_holder_initialized(&i_gh))
225 		gfs2_glock_dq_uninit(&i_gh);
226 	iget_failed(inode);
227 	return ERR_PTR(error);
228 }
229 
230 /**
231  * gfs2_lookup_by_inum - look up an inode by inode number
232  * @sdp: The super block
233  * @no_addr: The inode number
234  * @no_formal_ino: The inode generation number (0 for any)
235  * @blktype: Requested block type (see gfs2_inode_lookup)
236  */
237 struct inode *gfs2_lookup_by_inum(struct gfs2_sbd *sdp, u64 no_addr,
238 				  u64 no_formal_ino, unsigned int blktype)
239 {
240 	struct super_block *sb = sdp->sd_vfs;
241 	struct inode *inode;
242 	int error;
243 
244 	inode = gfs2_inode_lookup(sb, DT_UNKNOWN, no_addr, no_formal_ino,
245 				  blktype);
246 	if (IS_ERR(inode))
247 		return inode;
248 
249 	if (no_formal_ino) {
250 		error = -EIO;
251 		if (GFS2_I(inode)->i_diskflags & GFS2_DIF_SYSTEM)
252 			goto fail_iput;
253 	}
254 	return inode;
255 
256 fail_iput:
257 	iput(inode);
258 	return ERR_PTR(error);
259 }
260 
261 
262 struct inode *gfs2_lookup_simple(struct inode *dip, const char *name)
263 {
264 	struct qstr qstr;
265 	struct inode *inode;
266 	gfs2_str2qstr(&qstr, name);
267 	inode = gfs2_lookupi(dip, &qstr, 1);
268 	/* gfs2_lookupi has inconsistent callers: vfs
269 	 * related routines expect NULL for no entry found,
270 	 * gfs2_lookup_simple callers expect ENOENT
271 	 * and do not check for NULL.
272 	 */
273 	if (inode == NULL)
274 		return ERR_PTR(-ENOENT);
275 	else
276 		return inode;
277 }
278 
279 
280 /**
281  * gfs2_lookupi - Look up a filename in a directory and return its inode
282  * @d_gh: An initialized holder for the directory glock
283  * @name: The name of the inode to look for
284  * @is_root: If 1, ignore the caller's permissions
285  * @i_gh: An uninitialized holder for the new inode glock
286  *
287  * This can be called via the VFS filldir function when NFS is doing
288  * a readdirplus and the inode which its intending to stat isn't
289  * already in cache. In this case we must not take the directory glock
290  * again, since the readdir call will have already taken that lock.
291  *
292  * Returns: errno
293  */
294 
295 struct inode *gfs2_lookupi(struct inode *dir, const struct qstr *name,
296 			   int is_root)
297 {
298 	struct super_block *sb = dir->i_sb;
299 	struct gfs2_inode *dip = GFS2_I(dir);
300 	struct gfs2_holder d_gh;
301 	int error = 0;
302 	struct inode *inode = NULL;
303 
304 	gfs2_holder_mark_uninitialized(&d_gh);
305 	if (!name->len || name->len > GFS2_FNAMESIZE)
306 		return ERR_PTR(-ENAMETOOLONG);
307 
308 	if ((name->len == 1 && memcmp(name->name, ".", 1) == 0) ||
309 	    (name->len == 2 && memcmp(name->name, "..", 2) == 0 &&
310 	     dir == d_inode(sb->s_root))) {
311 		igrab(dir);
312 		return dir;
313 	}
314 
315 	if (gfs2_glock_is_locked_by_me(dip->i_gl) == NULL) {
316 		error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh);
317 		if (error)
318 			return ERR_PTR(error);
319 	}
320 
321 	if (!is_root) {
322 		error = gfs2_permission(dir, MAY_EXEC);
323 		if (error)
324 			goto out;
325 	}
326 
327 	inode = gfs2_dir_search(dir, name, false);
328 	if (IS_ERR(inode))
329 		error = PTR_ERR(inode);
330 out:
331 	if (gfs2_holder_initialized(&d_gh))
332 		gfs2_glock_dq_uninit(&d_gh);
333 	if (error == -ENOENT)
334 		return NULL;
335 	return inode ? inode : ERR_PTR(error);
336 }
337 
338 /**
339  * create_ok - OK to create a new on-disk inode here?
340  * @dip:  Directory in which dinode is to be created
341  * @name:  Name of new dinode
342  * @mode:
343  *
344  * Returns: errno
345  */
346 
347 static int create_ok(struct gfs2_inode *dip, const struct qstr *name,
348 		     umode_t mode)
349 {
350 	int error;
351 
352 	error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC);
353 	if (error)
354 		return error;
355 
356 	/*  Don't create entries in an unlinked directory  */
357 	if (!dip->i_inode.i_nlink)
358 		return -ENOENT;
359 
360 	if (dip->i_entries == (u32)-1)
361 		return -EFBIG;
362 	if (S_ISDIR(mode) && dip->i_inode.i_nlink == (u32)-1)
363 		return -EMLINK;
364 
365 	return 0;
366 }
367 
368 static void munge_mode_uid_gid(const struct gfs2_inode *dip,
369 			       struct inode *inode)
370 {
371 	if (GFS2_SB(&dip->i_inode)->sd_args.ar_suiddir &&
372 	    (dip->i_inode.i_mode & S_ISUID) &&
373 	    !uid_eq(dip->i_inode.i_uid, GLOBAL_ROOT_UID)) {
374 		if (S_ISDIR(inode->i_mode))
375 			inode->i_mode |= S_ISUID;
376 		else if (!uid_eq(dip->i_inode.i_uid, current_fsuid()))
377 			inode->i_mode &= ~07111;
378 		inode->i_uid = dip->i_inode.i_uid;
379 	} else
380 		inode->i_uid = current_fsuid();
381 
382 	if (dip->i_inode.i_mode & S_ISGID) {
383 		if (S_ISDIR(inode->i_mode))
384 			inode->i_mode |= S_ISGID;
385 		inode->i_gid = dip->i_inode.i_gid;
386 	} else
387 		inode->i_gid = current_fsgid();
388 }
389 
390 static int alloc_dinode(struct gfs2_inode *ip, u32 flags, unsigned *dblocks)
391 {
392 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
393 	struct gfs2_alloc_parms ap = { .target = *dblocks, .aflags = flags, };
394 	int error;
395 
396 	error = gfs2_quota_lock_check(ip, &ap);
397 	if (error)
398 		goto out;
399 
400 	error = gfs2_inplace_reserve(ip, &ap);
401 	if (error)
402 		goto out_quota;
403 
404 	error = gfs2_trans_begin(sdp, (*dblocks * RES_RG_BIT) + RES_STATFS + RES_QUOTA, 0);
405 	if (error)
406 		goto out_ipreserv;
407 
408 	error = gfs2_alloc_blocks(ip, &ip->i_no_addr, dblocks, 1, &ip->i_generation);
409 	ip->i_no_formal_ino = ip->i_generation;
410 	ip->i_inode.i_ino = ip->i_no_addr;
411 	ip->i_goal = ip->i_no_addr;
412 
413 	gfs2_trans_end(sdp);
414 
415 out_ipreserv:
416 	gfs2_inplace_release(ip);
417 out_quota:
418 	gfs2_quota_unlock(ip);
419 out:
420 	return error;
421 }
422 
423 static void gfs2_init_dir(struct buffer_head *dibh,
424 			  const struct gfs2_inode *parent)
425 {
426 	struct gfs2_dinode *di = (struct gfs2_dinode *)dibh->b_data;
427 	struct gfs2_dirent *dent = (struct gfs2_dirent *)(di+1);
428 
429 	gfs2_qstr2dirent(&gfs2_qdot, GFS2_DIRENT_SIZE(gfs2_qdot.len), dent);
430 	dent->de_inum = di->di_num; /* already GFS2 endian */
431 	dent->de_type = cpu_to_be16(DT_DIR);
432 
433 	dent = (struct gfs2_dirent *)((char*)dent + GFS2_DIRENT_SIZE(1));
434 	gfs2_qstr2dirent(&gfs2_qdotdot, dibh->b_size - GFS2_DIRENT_SIZE(1) - sizeof(struct gfs2_dinode), dent);
435 	gfs2_inum_out(parent, dent);
436 	dent->de_type = cpu_to_be16(DT_DIR);
437 
438 }
439 
440 /**
441  * gfs2_init_xattr - Initialise an xattr block for a new inode
442  * @ip: The inode in question
443  *
444  * This sets up an empty xattr block for a new inode, ready to
445  * take any ACLs, LSM xattrs, etc.
446  */
447 
448 static void gfs2_init_xattr(struct gfs2_inode *ip)
449 {
450 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
451 	struct buffer_head *bh;
452 	struct gfs2_ea_header *ea;
453 
454 	bh = gfs2_meta_new(ip->i_gl, ip->i_eattr);
455 	gfs2_trans_add_meta(ip->i_gl, bh);
456 	gfs2_metatype_set(bh, GFS2_METATYPE_EA, GFS2_FORMAT_EA);
457 	gfs2_buffer_clear_tail(bh, sizeof(struct gfs2_meta_header));
458 
459 	ea = GFS2_EA_BH2FIRST(bh);
460 	ea->ea_rec_len = cpu_to_be32(sdp->sd_jbsize);
461 	ea->ea_type = GFS2_EATYPE_UNUSED;
462 	ea->ea_flags = GFS2_EAFLAG_LAST;
463 
464 	brelse(bh);
465 }
466 
467 /**
468  * init_dinode - Fill in a new dinode structure
469  * @dip: The directory this inode is being created in
470  * @ip: The inode
471  * @symname: The symlink destination (if a symlink)
472  * @bhp: The buffer head (returned to caller)
473  *
474  */
475 
476 static void init_dinode(struct gfs2_inode *dip, struct gfs2_inode *ip,
477 			const char *symname)
478 {
479 	struct gfs2_dinode *di;
480 	struct buffer_head *dibh;
481 
482 	dibh = gfs2_meta_new(ip->i_gl, ip->i_no_addr);
483 	gfs2_trans_add_meta(ip->i_gl, dibh);
484 	di = (struct gfs2_dinode *)dibh->b_data;
485 	gfs2_dinode_out(ip, di);
486 
487 	di->di_major = cpu_to_be32(MAJOR(ip->i_inode.i_rdev));
488 	di->di_minor = cpu_to_be32(MINOR(ip->i_inode.i_rdev));
489 	di->__pad1 = 0;
490 	di->__pad2 = 0;
491 	di->__pad3 = 0;
492 	memset(&di->__pad4, 0, sizeof(di->__pad4));
493 	memset(&di->di_reserved, 0, sizeof(di->di_reserved));
494 	gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
495 
496 	switch(ip->i_inode.i_mode & S_IFMT) {
497 	case S_IFDIR:
498 		gfs2_init_dir(dibh, dip);
499 		break;
500 	case S_IFLNK:
501 		memcpy(dibh->b_data + sizeof(struct gfs2_dinode), symname, ip->i_inode.i_size);
502 		break;
503 	}
504 
505 	set_buffer_uptodate(dibh);
506 	brelse(dibh);
507 }
508 
509 /**
510  * gfs2_trans_da_blocks - Calculate number of blocks to link inode
511  * @dip: The directory we are linking into
512  * @da: The dir add information
513  * @nr_inodes: The number of inodes involved
514  *
515  * This calculate the number of blocks we need to reserve in a
516  * transaction to link @nr_inodes into a directory. In most cases
517  * @nr_inodes will be 2 (the directory plus the inode being linked in)
518  * but in case of rename, 4 may be required.
519  *
520  * Returns: Number of blocks
521  */
522 
523 static unsigned gfs2_trans_da_blks(const struct gfs2_inode *dip,
524 				   const struct gfs2_diradd *da,
525 				   unsigned nr_inodes)
526 {
527 	return da->nr_blocks + gfs2_rg_blocks(dip, da->nr_blocks) +
528 	       (nr_inodes * RES_DINODE) + RES_QUOTA + RES_STATFS;
529 }
530 
531 static int link_dinode(struct gfs2_inode *dip, const struct qstr *name,
532 		       struct gfs2_inode *ip, struct gfs2_diradd *da)
533 {
534 	struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
535 	struct gfs2_alloc_parms ap = { .target = da->nr_blocks, };
536 	int error;
537 
538 	if (da->nr_blocks) {
539 		error = gfs2_quota_lock_check(dip, &ap);
540 		if (error)
541 			goto fail_quota_locks;
542 
543 		error = gfs2_inplace_reserve(dip, &ap);
544 		if (error)
545 			goto fail_quota_locks;
546 
547 		error = gfs2_trans_begin(sdp, gfs2_trans_da_blks(dip, da, 2), 0);
548 		if (error)
549 			goto fail_ipreserv;
550 	} else {
551 		error = gfs2_trans_begin(sdp, RES_LEAF + 2 * RES_DINODE, 0);
552 		if (error)
553 			goto fail_quota_locks;
554 	}
555 
556 	error = gfs2_dir_add(&dip->i_inode, name, ip, da);
557 
558 	gfs2_trans_end(sdp);
559 fail_ipreserv:
560 	gfs2_inplace_release(dip);
561 fail_quota_locks:
562 	gfs2_quota_unlock(dip);
563 	return error;
564 }
565 
566 static int gfs2_initxattrs(struct inode *inode, const struct xattr *xattr_array,
567 		    void *fs_info)
568 {
569 	const struct xattr *xattr;
570 	int err = 0;
571 
572 	for (xattr = xattr_array; xattr->name != NULL; xattr++) {
573 		err = __gfs2_xattr_set(inode, xattr->name, xattr->value,
574 				       xattr->value_len, 0,
575 				       GFS2_EATYPE_SECURITY);
576 		if (err < 0)
577 			break;
578 	}
579 	return err;
580 }
581 
582 /**
583  * gfs2_create_inode - Create a new inode
584  * @dir: The parent directory
585  * @dentry: The new dentry
586  * @file: If non-NULL, the file which is being opened
587  * @mode: The permissions on the new inode
588  * @dev: For device nodes, this is the device number
589  * @symname: For symlinks, this is the link destination
590  * @size: The initial size of the inode (ignored for directories)
591  *
592  * Returns: 0 on success, or error code
593  */
594 
595 static int gfs2_create_inode(struct inode *dir, struct dentry *dentry,
596 			     struct file *file,
597 			     umode_t mode, dev_t dev, const char *symname,
598 			     unsigned int size, int excl)
599 {
600 	const struct qstr *name = &dentry->d_name;
601 	struct posix_acl *default_acl, *acl;
602 	struct gfs2_holder ghs[2];
603 	struct inode *inode = NULL;
604 	struct gfs2_inode *dip = GFS2_I(dir), *ip;
605 	struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
606 	struct gfs2_glock *io_gl = NULL;
607 	int error, free_vfs_inode = 1;
608 	u32 aflags = 0;
609 	unsigned blocks = 1;
610 	struct gfs2_diradd da = { .bh = NULL, .save_loc = 1, };
611 
612 	if (!name->len || name->len > GFS2_FNAMESIZE)
613 		return -ENAMETOOLONG;
614 
615 	error = gfs2_qa_get(dip);
616 	if (error)
617 		return error;
618 
619 	error = gfs2_rindex_update(sdp);
620 	if (error)
621 		goto fail;
622 
623 	error = gfs2_glock_nq_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
624 	if (error)
625 		goto fail;
626 	gfs2_holder_mark_uninitialized(ghs + 1);
627 
628 	error = create_ok(dip, name, mode);
629 	if (error)
630 		goto fail_gunlock;
631 
632 	inode = gfs2_dir_search(dir, &dentry->d_name, !S_ISREG(mode) || excl);
633 	error = PTR_ERR(inode);
634 	if (!IS_ERR(inode)) {
635 		if (S_ISDIR(inode->i_mode)) {
636 			iput(inode);
637 			inode = ERR_PTR(-EISDIR);
638 			goto fail_gunlock;
639 		}
640 		d_instantiate(dentry, inode);
641 		error = 0;
642 		if (file) {
643 			if (S_ISREG(inode->i_mode))
644 				error = finish_open(file, dentry, gfs2_open_common);
645 			else
646 				error = finish_no_open(file, NULL);
647 		}
648 		gfs2_glock_dq_uninit(ghs);
649 		goto fail;
650 	} else if (error != -ENOENT) {
651 		goto fail_gunlock;
652 	}
653 
654 	error = gfs2_diradd_alloc_required(dir, name, &da);
655 	if (error < 0)
656 		goto fail_gunlock;
657 
658 	inode = new_inode(sdp->sd_vfs);
659 	error = -ENOMEM;
660 	if (!inode)
661 		goto fail_gunlock;
662 
663 	error = posix_acl_create(dir, &mode, &default_acl, &acl);
664 	if (error)
665 		goto fail_gunlock;
666 
667 	ip = GFS2_I(inode);
668 	error = gfs2_qa_get(ip);
669 	if (error)
670 		goto fail_free_acls;
671 
672 	inode->i_mode = mode;
673 	set_nlink(inode, S_ISDIR(mode) ? 2 : 1);
674 	inode->i_rdev = dev;
675 	inode->i_size = size;
676 	inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
677 	munge_mode_uid_gid(dip, inode);
678 	check_and_update_goal(dip);
679 	ip->i_goal = dip->i_goal;
680 	ip->i_diskflags = 0;
681 	ip->i_eattr = 0;
682 	ip->i_height = 0;
683 	ip->i_depth = 0;
684 	ip->i_entries = 0;
685 	ip->i_no_addr = 0; /* Temporarily zero until real addr is assigned */
686 
687 	switch(mode & S_IFMT) {
688 	case S_IFREG:
689 		if ((dip->i_diskflags & GFS2_DIF_INHERIT_JDATA) ||
690 		    gfs2_tune_get(sdp, gt_new_files_jdata))
691 			ip->i_diskflags |= GFS2_DIF_JDATA;
692 		gfs2_set_aops(inode);
693 		break;
694 	case S_IFDIR:
695 		ip->i_diskflags |= (dip->i_diskflags & GFS2_DIF_INHERIT_JDATA);
696 		ip->i_diskflags |= GFS2_DIF_JDATA;
697 		ip->i_entries = 2;
698 		break;
699 	}
700 
701 	/* Force SYSTEM flag on all files and subdirs of a SYSTEM directory */
702 	if (dip->i_diskflags & GFS2_DIF_SYSTEM)
703 		ip->i_diskflags |= GFS2_DIF_SYSTEM;
704 
705 	gfs2_set_inode_flags(inode);
706 
707 	if ((GFS2_I(d_inode(sdp->sd_root_dir)) == dip) ||
708 	    (dip->i_diskflags & GFS2_DIF_TOPDIR))
709 		aflags |= GFS2_AF_ORLOV;
710 
711 	if (default_acl || acl)
712 		blocks++;
713 
714 	error = alloc_dinode(ip, aflags, &blocks);
715 	if (error)
716 		goto fail_free_inode;
717 
718 	gfs2_set_inode_blocks(inode, blocks);
719 
720 	error = gfs2_glock_get(sdp, ip->i_no_addr, &gfs2_inode_glops, CREATE, &ip->i_gl);
721 	if (error)
722 		goto fail_free_inode;
723 	flush_delayed_work(&ip->i_gl->gl_work);
724 	glock_set_object(ip->i_gl, ip);
725 
726 	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, ghs + 1);
727 	if (error)
728 		goto fail_free_inode;
729 
730 	error = gfs2_trans_begin(sdp, blocks, 0);
731 	if (error)
732 		goto fail_free_inode;
733 
734 	if (blocks > 1) {
735 		ip->i_eattr = ip->i_no_addr + 1;
736 		gfs2_init_xattr(ip);
737 	}
738 	init_dinode(dip, ip, symname);
739 	gfs2_trans_end(sdp);
740 
741 	error = gfs2_glock_get(sdp, ip->i_no_addr, &gfs2_iopen_glops, CREATE, &io_gl);
742 	if (error)
743 		goto fail_free_inode;
744 
745 	BUG_ON(test_and_set_bit(GLF_INODE_CREATING, &io_gl->gl_flags));
746 
747 	error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED, GL_EXACT, &ip->i_iopen_gh);
748 	if (error)
749 		goto fail_gunlock2;
750 
751 	gfs2_cancel_delete_work(ip->i_iopen_gh.gh_gl);
752 	glock_set_object(ip->i_iopen_gh.gh_gl, ip);
753 	gfs2_set_iop(inode);
754 	insert_inode_hash(inode);
755 
756 	free_vfs_inode = 0; /* After this point, the inode is no longer
757 			       considered free. Any failures need to undo
758 			       the gfs2 structures. */
759 	if (default_acl) {
760 		error = __gfs2_set_acl(inode, default_acl, ACL_TYPE_DEFAULT);
761 		if (error)
762 			goto fail_gunlock3;
763 		posix_acl_release(default_acl);
764 		default_acl = NULL;
765 	}
766 	if (acl) {
767 		error = __gfs2_set_acl(inode, acl, ACL_TYPE_ACCESS);
768 		if (error)
769 			goto fail_gunlock3;
770 		posix_acl_release(acl);
771 		acl = NULL;
772 	}
773 
774 	error = security_inode_init_security(&ip->i_inode, &dip->i_inode, name,
775 					     &gfs2_initxattrs, NULL);
776 	if (error)
777 		goto fail_gunlock3;
778 
779 	error = link_dinode(dip, name, ip, &da);
780 	if (error)
781 		goto fail_gunlock3;
782 
783 	mark_inode_dirty(inode);
784 	d_instantiate(dentry, inode);
785 	/* After instantiate, errors should result in evict which will destroy
786 	 * both inode and iopen glocks properly. */
787 	if (file) {
788 		file->f_mode |= FMODE_CREATED;
789 		error = finish_open(file, dentry, gfs2_open_common);
790 	}
791 	gfs2_glock_dq_uninit(ghs);
792 	gfs2_qa_put(ip);
793 	gfs2_glock_dq_uninit(ghs + 1);
794 	clear_bit(GLF_INODE_CREATING, &io_gl->gl_flags);
795 	gfs2_glock_put(io_gl);
796 	gfs2_qa_put(dip);
797 	return error;
798 
799 fail_gunlock3:
800 	glock_clear_object(io_gl, ip);
801 	gfs2_glock_dq_uninit(&ip->i_iopen_gh);
802 fail_gunlock2:
803 	clear_bit(GLF_INODE_CREATING, &io_gl->gl_flags);
804 	gfs2_glock_put(io_gl);
805 fail_free_inode:
806 	if (ip->i_gl) {
807 		glock_clear_object(ip->i_gl, ip);
808 		if (free_vfs_inode) /* else evict will do the put for us */
809 			gfs2_glock_put(ip->i_gl);
810 	}
811 	gfs2_rs_delete(ip, NULL);
812 	gfs2_qa_put(ip);
813 fail_free_acls:
814 	posix_acl_release(default_acl);
815 	posix_acl_release(acl);
816 fail_gunlock:
817 	gfs2_dir_no_add(&da);
818 	gfs2_glock_dq_uninit(ghs);
819 	if (!IS_ERR_OR_NULL(inode)) {
820 		clear_nlink(inode);
821 		if (!free_vfs_inode)
822 			mark_inode_dirty(inode);
823 		set_bit(free_vfs_inode ? GIF_FREE_VFS_INODE : GIF_ALLOC_FAILED,
824 			&GFS2_I(inode)->i_flags);
825 		iput(inode);
826 	}
827 	if (gfs2_holder_initialized(ghs + 1))
828 		gfs2_glock_dq_uninit(ghs + 1);
829 fail:
830 	gfs2_qa_put(dip);
831 	return error;
832 }
833 
834 /**
835  * gfs2_create - Create a file
836  * @dir: The directory in which to create the file
837  * @dentry: The dentry of the new file
838  * @mode: The mode of the new file
839  *
840  * Returns: errno
841  */
842 
843 static int gfs2_create(struct inode *dir, struct dentry *dentry,
844 		       umode_t mode, bool excl)
845 {
846 	return gfs2_create_inode(dir, dentry, NULL, S_IFREG | mode, 0, NULL, 0, excl);
847 }
848 
849 /**
850  * __gfs2_lookup - Look up a filename in a directory and return its inode
851  * @dir: The directory inode
852  * @dentry: The dentry of the new inode
853  * @file: File to be opened
854  *
855  *
856  * Returns: errno
857  */
858 
859 static struct dentry *__gfs2_lookup(struct inode *dir, struct dentry *dentry,
860 				    struct file *file)
861 {
862 	struct inode *inode;
863 	struct dentry *d;
864 	struct gfs2_holder gh;
865 	struct gfs2_glock *gl;
866 	int error;
867 
868 	inode = gfs2_lookupi(dir, &dentry->d_name, 0);
869 	if (inode == NULL) {
870 		d_add(dentry, NULL);
871 		return NULL;
872 	}
873 	if (IS_ERR(inode))
874 		return ERR_CAST(inode);
875 
876 	gl = GFS2_I(inode)->i_gl;
877 	error = gfs2_glock_nq_init(gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
878 	if (error) {
879 		iput(inode);
880 		return ERR_PTR(error);
881 	}
882 
883 	d = d_splice_alias(inode, dentry);
884 	if (IS_ERR(d)) {
885 		gfs2_glock_dq_uninit(&gh);
886 		return d;
887 	}
888 	if (file && S_ISREG(inode->i_mode))
889 		error = finish_open(file, dentry, gfs2_open_common);
890 
891 	gfs2_glock_dq_uninit(&gh);
892 	if (error) {
893 		dput(d);
894 		return ERR_PTR(error);
895 	}
896 	return d;
897 }
898 
899 static struct dentry *gfs2_lookup(struct inode *dir, struct dentry *dentry,
900 				  unsigned flags)
901 {
902 	return __gfs2_lookup(dir, dentry, NULL);
903 }
904 
905 /**
906  * gfs2_link - Link to a file
907  * @old_dentry: The inode to link
908  * @dir: Add link to this directory
909  * @dentry: The name of the link
910  *
911  * Link the inode in "old_dentry" into the directory "dir" with the
912  * name in "dentry".
913  *
914  * Returns: errno
915  */
916 
917 static int gfs2_link(struct dentry *old_dentry, struct inode *dir,
918 		     struct dentry *dentry)
919 {
920 	struct gfs2_inode *dip = GFS2_I(dir);
921 	struct gfs2_sbd *sdp = GFS2_SB(dir);
922 	struct inode *inode = d_inode(old_dentry);
923 	struct gfs2_inode *ip = GFS2_I(inode);
924 	struct gfs2_holder ghs[2];
925 	struct buffer_head *dibh;
926 	struct gfs2_diradd da = { .bh = NULL, .save_loc = 1, };
927 	int error;
928 
929 	if (S_ISDIR(inode->i_mode))
930 		return -EPERM;
931 
932 	error = gfs2_qa_get(dip);
933 	if (error)
934 		return error;
935 
936 	gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
937 	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + 1);
938 
939 	error = gfs2_glock_nq(ghs); /* parent */
940 	if (error)
941 		goto out_parent;
942 
943 	error = gfs2_glock_nq(ghs + 1); /* child */
944 	if (error)
945 		goto out_child;
946 
947 	error = -ENOENT;
948 	if (inode->i_nlink == 0)
949 		goto out_gunlock;
950 
951 	error = gfs2_permission(dir, MAY_WRITE | MAY_EXEC);
952 	if (error)
953 		goto out_gunlock;
954 
955 	error = gfs2_dir_check(dir, &dentry->d_name, NULL);
956 	switch (error) {
957 	case -ENOENT:
958 		break;
959 	case 0:
960 		error = -EEXIST;
961 	default:
962 		goto out_gunlock;
963 	}
964 
965 	error = -EINVAL;
966 	if (!dip->i_inode.i_nlink)
967 		goto out_gunlock;
968 	error = -EFBIG;
969 	if (dip->i_entries == (u32)-1)
970 		goto out_gunlock;
971 	error = -EPERM;
972 	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
973 		goto out_gunlock;
974 	error = -EINVAL;
975 	if (!ip->i_inode.i_nlink)
976 		goto out_gunlock;
977 	error = -EMLINK;
978 	if (ip->i_inode.i_nlink == (u32)-1)
979 		goto out_gunlock;
980 
981 	error = gfs2_diradd_alloc_required(dir, &dentry->d_name, &da);
982 	if (error < 0)
983 		goto out_gunlock;
984 
985 	if (da.nr_blocks) {
986 		struct gfs2_alloc_parms ap = { .target = da.nr_blocks, };
987 		error = gfs2_quota_lock_check(dip, &ap);
988 		if (error)
989 			goto out_gunlock;
990 
991 		error = gfs2_inplace_reserve(dip, &ap);
992 		if (error)
993 			goto out_gunlock_q;
994 
995 		error = gfs2_trans_begin(sdp, gfs2_trans_da_blks(dip, &da, 2), 0);
996 		if (error)
997 			goto out_ipres;
998 	} else {
999 		error = gfs2_trans_begin(sdp, 2 * RES_DINODE + RES_LEAF, 0);
1000 		if (error)
1001 			goto out_ipres;
1002 	}
1003 
1004 	error = gfs2_meta_inode_buffer(ip, &dibh);
1005 	if (error)
1006 		goto out_end_trans;
1007 
1008 	error = gfs2_dir_add(dir, &dentry->d_name, ip, &da);
1009 	if (error)
1010 		goto out_brelse;
1011 
1012 	gfs2_trans_add_meta(ip->i_gl, dibh);
1013 	inc_nlink(&ip->i_inode);
1014 	ip->i_inode.i_ctime = current_time(&ip->i_inode);
1015 	ihold(inode);
1016 	d_instantiate(dentry, inode);
1017 	mark_inode_dirty(inode);
1018 
1019 out_brelse:
1020 	brelse(dibh);
1021 out_end_trans:
1022 	gfs2_trans_end(sdp);
1023 out_ipres:
1024 	if (da.nr_blocks)
1025 		gfs2_inplace_release(dip);
1026 out_gunlock_q:
1027 	if (da.nr_blocks)
1028 		gfs2_quota_unlock(dip);
1029 out_gunlock:
1030 	gfs2_dir_no_add(&da);
1031 	gfs2_glock_dq(ghs + 1);
1032 out_child:
1033 	gfs2_glock_dq(ghs);
1034 out_parent:
1035 	gfs2_qa_put(dip);
1036 	gfs2_holder_uninit(ghs);
1037 	gfs2_holder_uninit(ghs + 1);
1038 	return error;
1039 }
1040 
1041 /*
1042  * gfs2_unlink_ok - check to see that a inode is still in a directory
1043  * @dip: the directory
1044  * @name: the name of the file
1045  * @ip: the inode
1046  *
1047  * Assumes that the lock on (at least) @dip is held.
1048  *
1049  * Returns: 0 if the parent/child relationship is correct, errno if it isn't
1050  */
1051 
1052 static int gfs2_unlink_ok(struct gfs2_inode *dip, const struct qstr *name,
1053 			  const struct gfs2_inode *ip)
1054 {
1055 	int error;
1056 
1057 	if (IS_IMMUTABLE(&ip->i_inode) || IS_APPEND(&ip->i_inode))
1058 		return -EPERM;
1059 
1060 	if ((dip->i_inode.i_mode & S_ISVTX) &&
1061 	    !uid_eq(dip->i_inode.i_uid, current_fsuid()) &&
1062 	    !uid_eq(ip->i_inode.i_uid, current_fsuid()) && !capable(CAP_FOWNER))
1063 		return -EPERM;
1064 
1065 	if (IS_APPEND(&dip->i_inode))
1066 		return -EPERM;
1067 
1068 	error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC);
1069 	if (error)
1070 		return error;
1071 
1072 	return gfs2_dir_check(&dip->i_inode, name, ip);
1073 }
1074 
1075 /**
1076  * gfs2_unlink_inode - Removes an inode from its parent dir and unlinks it
1077  * @dip: The parent directory
1078  * @name: The name of the entry in the parent directory
1079  * @inode: The inode to be removed
1080  *
1081  * Called with all the locks and in a transaction. This will only be
1082  * called for a directory after it has been checked to ensure it is empty.
1083  *
1084  * Returns: 0 on success, or an error
1085  */
1086 
1087 static int gfs2_unlink_inode(struct gfs2_inode *dip,
1088 			     const struct dentry *dentry)
1089 {
1090 	struct inode *inode = d_inode(dentry);
1091 	struct gfs2_inode *ip = GFS2_I(inode);
1092 	int error;
1093 
1094 	error = gfs2_dir_del(dip, dentry);
1095 	if (error)
1096 		return error;
1097 
1098 	ip->i_entries = 0;
1099 	inode->i_ctime = current_time(inode);
1100 	if (S_ISDIR(inode->i_mode))
1101 		clear_nlink(inode);
1102 	else
1103 		drop_nlink(inode);
1104 	mark_inode_dirty(inode);
1105 	if (inode->i_nlink == 0)
1106 		gfs2_unlink_di(inode);
1107 	return 0;
1108 }
1109 
1110 
1111 /**
1112  * gfs2_unlink - Unlink an inode (this does rmdir as well)
1113  * @dir: The inode of the directory containing the inode to unlink
1114  * @dentry: The file itself
1115  *
1116  * This routine uses the type of the inode as a flag to figure out
1117  * whether this is an unlink or an rmdir.
1118  *
1119  * Returns: errno
1120  */
1121 
1122 static int gfs2_unlink(struct inode *dir, struct dentry *dentry)
1123 {
1124 	struct gfs2_inode *dip = GFS2_I(dir);
1125 	struct gfs2_sbd *sdp = GFS2_SB(dir);
1126 	struct inode *inode = d_inode(dentry);
1127 	struct gfs2_inode *ip = GFS2_I(inode);
1128 	struct gfs2_holder ghs[3];
1129 	struct gfs2_rgrpd *rgd;
1130 	int error;
1131 
1132 	error = gfs2_rindex_update(sdp);
1133 	if (error)
1134 		return error;
1135 
1136 	error = -EROFS;
1137 
1138 	gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
1139 	gfs2_holder_init(ip->i_gl,  LM_ST_EXCLUSIVE, 0, ghs + 1);
1140 
1141 	rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr, 1);
1142 	if (!rgd)
1143 		goto out_inodes;
1144 
1145 	gfs2_holder_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, ghs + 2);
1146 
1147 
1148 	error = gfs2_glock_nq(ghs); /* parent */
1149 	if (error)
1150 		goto out_parent;
1151 
1152 	error = gfs2_glock_nq(ghs + 1); /* child */
1153 	if (error)
1154 		goto out_child;
1155 
1156 	error = -ENOENT;
1157 	if (inode->i_nlink == 0)
1158 		goto out_rgrp;
1159 
1160 	if (S_ISDIR(inode->i_mode)) {
1161 		error = -ENOTEMPTY;
1162 		if (ip->i_entries > 2 || inode->i_nlink > 2)
1163 			goto out_rgrp;
1164 	}
1165 
1166 	error = gfs2_glock_nq(ghs + 2); /* rgrp */
1167 	if (error)
1168 		goto out_rgrp;
1169 
1170 	error = gfs2_unlink_ok(dip, &dentry->d_name, ip);
1171 	if (error)
1172 		goto out_gunlock;
1173 
1174 	error = gfs2_trans_begin(sdp, 2*RES_DINODE + 3*RES_LEAF + RES_RG_BIT, 0);
1175 	if (error)
1176 		goto out_gunlock;
1177 
1178 	error = gfs2_unlink_inode(dip, dentry);
1179 	gfs2_trans_end(sdp);
1180 
1181 out_gunlock:
1182 	gfs2_glock_dq(ghs + 2);
1183 out_rgrp:
1184 	gfs2_glock_dq(ghs + 1);
1185 out_child:
1186 	gfs2_glock_dq(ghs);
1187 out_parent:
1188 	gfs2_holder_uninit(ghs + 2);
1189 out_inodes:
1190 	gfs2_holder_uninit(ghs + 1);
1191 	gfs2_holder_uninit(ghs);
1192 	return error;
1193 }
1194 
1195 /**
1196  * gfs2_symlink - Create a symlink
1197  * @dir: The directory to create the symlink in
1198  * @dentry: The dentry to put the symlink in
1199  * @symname: The thing which the link points to
1200  *
1201  * Returns: errno
1202  */
1203 
1204 static int gfs2_symlink(struct inode *dir, struct dentry *dentry,
1205 			const char *symname)
1206 {
1207 	unsigned int size;
1208 
1209 	size = strlen(symname);
1210 	if (size >= gfs2_max_stuffed_size(GFS2_I(dir)))
1211 		return -ENAMETOOLONG;
1212 
1213 	return gfs2_create_inode(dir, dentry, NULL, S_IFLNK | S_IRWXUGO, 0, symname, size, 0);
1214 }
1215 
1216 /**
1217  * gfs2_mkdir - Make a directory
1218  * @dir: The parent directory of the new one
1219  * @dentry: The dentry of the new directory
1220  * @mode: The mode of the new directory
1221  *
1222  * Returns: errno
1223  */
1224 
1225 static int gfs2_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
1226 {
1227 	unsigned dsize = gfs2_max_stuffed_size(GFS2_I(dir));
1228 	return gfs2_create_inode(dir, dentry, NULL, S_IFDIR | mode, 0, NULL, dsize, 0);
1229 }
1230 
1231 /**
1232  * gfs2_mknod - Make a special file
1233  * @dir: The directory in which the special file will reside
1234  * @dentry: The dentry of the special file
1235  * @mode: The mode of the special file
1236  * @dev: The device specification of the special file
1237  *
1238  */
1239 
1240 static int gfs2_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
1241 		      dev_t dev)
1242 {
1243 	return gfs2_create_inode(dir, dentry, NULL, mode, dev, NULL, 0, 0);
1244 }
1245 
1246 /**
1247  * gfs2_atomic_open - Atomically open a file
1248  * @dir: The directory
1249  * @dentry: The proposed new entry
1250  * @file: The proposed new struct file
1251  * @flags: open flags
1252  * @mode: File mode
1253  *
1254  * Returns: error code or 0 for success
1255  */
1256 
1257 static int gfs2_atomic_open(struct inode *dir, struct dentry *dentry,
1258 			    struct file *file, unsigned flags,
1259 			    umode_t mode)
1260 {
1261 	struct dentry *d;
1262 	bool excl = !!(flags & O_EXCL);
1263 
1264 	if (!d_in_lookup(dentry))
1265 		goto skip_lookup;
1266 
1267 	d = __gfs2_lookup(dir, dentry, file);
1268 	if (IS_ERR(d))
1269 		return PTR_ERR(d);
1270 	if (d != NULL)
1271 		dentry = d;
1272 	if (d_really_is_positive(dentry)) {
1273 		if (!(file->f_mode & FMODE_OPENED))
1274 			return finish_no_open(file, d);
1275 		dput(d);
1276 		return excl && (flags & O_CREAT) ? -EEXIST : 0;
1277 	}
1278 
1279 	BUG_ON(d != NULL);
1280 
1281 skip_lookup:
1282 	if (!(flags & O_CREAT))
1283 		return -ENOENT;
1284 
1285 	return gfs2_create_inode(dir, dentry, file, S_IFREG | mode, 0, NULL, 0, excl);
1286 }
1287 
1288 /*
1289  * gfs2_ok_to_move - check if it's ok to move a directory to another directory
1290  * @this: move this
1291  * @to: to here
1292  *
1293  * Follow @to back to the root and make sure we don't encounter @this
1294  * Assumes we already hold the rename lock.
1295  *
1296  * Returns: errno
1297  */
1298 
1299 static int gfs2_ok_to_move(struct gfs2_inode *this, struct gfs2_inode *to)
1300 {
1301 	struct inode *dir = &to->i_inode;
1302 	struct super_block *sb = dir->i_sb;
1303 	struct inode *tmp;
1304 	int error = 0;
1305 
1306 	igrab(dir);
1307 
1308 	for (;;) {
1309 		if (dir == &this->i_inode) {
1310 			error = -EINVAL;
1311 			break;
1312 		}
1313 		if (dir == d_inode(sb->s_root)) {
1314 			error = 0;
1315 			break;
1316 		}
1317 
1318 		tmp = gfs2_lookupi(dir, &gfs2_qdotdot, 1);
1319 		if (!tmp) {
1320 			error = -ENOENT;
1321 			break;
1322 		}
1323 		if (IS_ERR(tmp)) {
1324 			error = PTR_ERR(tmp);
1325 			break;
1326 		}
1327 
1328 		iput(dir);
1329 		dir = tmp;
1330 	}
1331 
1332 	iput(dir);
1333 
1334 	return error;
1335 }
1336 
1337 /**
1338  * update_moved_ino - Update an inode that's being moved
1339  * @ip: The inode being moved
1340  * @ndip: The parent directory of the new filename
1341  * @dir_rename: True of ip is a directory
1342  *
1343  * Returns: errno
1344  */
1345 
1346 static int update_moved_ino(struct gfs2_inode *ip, struct gfs2_inode *ndip,
1347 			    int dir_rename)
1348 {
1349 	if (dir_rename)
1350 		return gfs2_dir_mvino(ip, &gfs2_qdotdot, ndip, DT_DIR);
1351 
1352 	ip->i_inode.i_ctime = current_time(&ip->i_inode);
1353 	mark_inode_dirty_sync(&ip->i_inode);
1354 	return 0;
1355 }
1356 
1357 
1358 /**
1359  * gfs2_rename - Rename a file
1360  * @odir: Parent directory of old file name
1361  * @odentry: The old dentry of the file
1362  * @ndir: Parent directory of new file name
1363  * @ndentry: The new dentry of the file
1364  *
1365  * Returns: errno
1366  */
1367 
1368 static int gfs2_rename(struct inode *odir, struct dentry *odentry,
1369 		       struct inode *ndir, struct dentry *ndentry)
1370 {
1371 	struct gfs2_inode *odip = GFS2_I(odir);
1372 	struct gfs2_inode *ndip = GFS2_I(ndir);
1373 	struct gfs2_inode *ip = GFS2_I(d_inode(odentry));
1374 	struct gfs2_inode *nip = NULL;
1375 	struct gfs2_sbd *sdp = GFS2_SB(odir);
1376 	struct gfs2_holder ghs[4], r_gh, rd_gh;
1377 	struct gfs2_rgrpd *nrgd;
1378 	unsigned int num_gh;
1379 	int dir_rename = 0;
1380 	struct gfs2_diradd da = { .nr_blocks = 0, .save_loc = 0, };
1381 	unsigned int x;
1382 	int error;
1383 
1384 	gfs2_holder_mark_uninitialized(&r_gh);
1385 	gfs2_holder_mark_uninitialized(&rd_gh);
1386 	if (d_really_is_positive(ndentry)) {
1387 		nip = GFS2_I(d_inode(ndentry));
1388 		if (ip == nip)
1389 			return 0;
1390 	}
1391 
1392 	error = gfs2_rindex_update(sdp);
1393 	if (error)
1394 		return error;
1395 
1396 	error = gfs2_qa_get(ndip);
1397 	if (error)
1398 		return error;
1399 
1400 	if (odip != ndip) {
1401 		error = gfs2_glock_nq_init(sdp->sd_rename_gl, LM_ST_EXCLUSIVE,
1402 					   0, &r_gh);
1403 		if (error)
1404 			goto out;
1405 
1406 		if (S_ISDIR(ip->i_inode.i_mode)) {
1407 			dir_rename = 1;
1408 			/* don't move a directory into its subdir */
1409 			error = gfs2_ok_to_move(ip, ndip);
1410 			if (error)
1411 				goto out_gunlock_r;
1412 		}
1413 	}
1414 
1415 	num_gh = 1;
1416 	gfs2_holder_init(odip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC, ghs);
1417 	if (odip != ndip) {
1418 		gfs2_holder_init(ndip->i_gl, LM_ST_EXCLUSIVE,GL_ASYNC,
1419 				 ghs + num_gh);
1420 		num_gh++;
1421 	}
1422 	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC, ghs + num_gh);
1423 	num_gh++;
1424 
1425 	if (nip) {
1426 		gfs2_holder_init(nip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC,
1427 				 ghs + num_gh);
1428 		num_gh++;
1429 	}
1430 
1431 	for (x = 0; x < num_gh; x++) {
1432 		error = gfs2_glock_nq(ghs + x);
1433 		if (error)
1434 			goto out_gunlock;
1435 	}
1436 	error = gfs2_glock_async_wait(num_gh, ghs);
1437 	if (error)
1438 		goto out_gunlock;
1439 
1440 	if (nip) {
1441 		/* Grab the resource group glock for unlink flag twiddling.
1442 		 * This is the case where the target dinode already exists
1443 		 * so we unlink before doing the rename.
1444 		 */
1445 		nrgd = gfs2_blk2rgrpd(sdp, nip->i_no_addr, 1);
1446 		if (!nrgd) {
1447 			error = -ENOENT;
1448 			goto out_gunlock;
1449 		}
1450 		error = gfs2_glock_nq_init(nrgd->rd_gl, LM_ST_EXCLUSIVE, 0,
1451 					   &rd_gh);
1452 		if (error)
1453 			goto out_gunlock;
1454 	}
1455 
1456 	error = -ENOENT;
1457 	if (ip->i_inode.i_nlink == 0)
1458 		goto out_gunlock;
1459 
1460 	/* Check out the old directory */
1461 
1462 	error = gfs2_unlink_ok(odip, &odentry->d_name, ip);
1463 	if (error)
1464 		goto out_gunlock;
1465 
1466 	/* Check out the new directory */
1467 
1468 	if (nip) {
1469 		error = gfs2_unlink_ok(ndip, &ndentry->d_name, nip);
1470 		if (error)
1471 			goto out_gunlock;
1472 
1473 		if (nip->i_inode.i_nlink == 0) {
1474 			error = -EAGAIN;
1475 			goto out_gunlock;
1476 		}
1477 
1478 		if (S_ISDIR(nip->i_inode.i_mode)) {
1479 			if (nip->i_entries < 2) {
1480 				gfs2_consist_inode(nip);
1481 				error = -EIO;
1482 				goto out_gunlock;
1483 			}
1484 			if (nip->i_entries > 2) {
1485 				error = -ENOTEMPTY;
1486 				goto out_gunlock;
1487 			}
1488 		}
1489 	} else {
1490 		error = gfs2_permission(ndir, MAY_WRITE | MAY_EXEC);
1491 		if (error)
1492 			goto out_gunlock;
1493 
1494 		error = gfs2_dir_check(ndir, &ndentry->d_name, NULL);
1495 		switch (error) {
1496 		case -ENOENT:
1497 			error = 0;
1498 			break;
1499 		case 0:
1500 			error = -EEXIST;
1501 		default:
1502 			goto out_gunlock;
1503 		}
1504 
1505 		if (odip != ndip) {
1506 			if (!ndip->i_inode.i_nlink) {
1507 				error = -ENOENT;
1508 				goto out_gunlock;
1509 			}
1510 			if (ndip->i_entries == (u32)-1) {
1511 				error = -EFBIG;
1512 				goto out_gunlock;
1513 			}
1514 			if (S_ISDIR(ip->i_inode.i_mode) &&
1515 			    ndip->i_inode.i_nlink == (u32)-1) {
1516 				error = -EMLINK;
1517 				goto out_gunlock;
1518 			}
1519 		}
1520 	}
1521 
1522 	/* Check out the dir to be renamed */
1523 
1524 	if (dir_rename) {
1525 		error = gfs2_permission(d_inode(odentry), MAY_WRITE);
1526 		if (error)
1527 			goto out_gunlock;
1528 	}
1529 
1530 	if (nip == NULL) {
1531 		error = gfs2_diradd_alloc_required(ndir, &ndentry->d_name, &da);
1532 		if (error)
1533 			goto out_gunlock;
1534 	}
1535 
1536 	if (da.nr_blocks) {
1537 		struct gfs2_alloc_parms ap = { .target = da.nr_blocks, };
1538 		error = gfs2_quota_lock_check(ndip, &ap);
1539 		if (error)
1540 			goto out_gunlock;
1541 
1542 		error = gfs2_inplace_reserve(ndip, &ap);
1543 		if (error)
1544 			goto out_gunlock_q;
1545 
1546 		error = gfs2_trans_begin(sdp, gfs2_trans_da_blks(ndip, &da, 4) +
1547 					 4 * RES_LEAF + 4, 0);
1548 		if (error)
1549 			goto out_ipreserv;
1550 	} else {
1551 		error = gfs2_trans_begin(sdp, 4 * RES_DINODE +
1552 					 5 * RES_LEAF + 4, 0);
1553 		if (error)
1554 			goto out_gunlock;
1555 	}
1556 
1557 	/* Remove the target file, if it exists */
1558 
1559 	if (nip)
1560 		error = gfs2_unlink_inode(ndip, ndentry);
1561 
1562 	error = update_moved_ino(ip, ndip, dir_rename);
1563 	if (error)
1564 		goto out_end_trans;
1565 
1566 	error = gfs2_dir_del(odip, odentry);
1567 	if (error)
1568 		goto out_end_trans;
1569 
1570 	error = gfs2_dir_add(ndir, &ndentry->d_name, ip, &da);
1571 	if (error)
1572 		goto out_end_trans;
1573 
1574 out_end_trans:
1575 	gfs2_trans_end(sdp);
1576 out_ipreserv:
1577 	if (da.nr_blocks)
1578 		gfs2_inplace_release(ndip);
1579 out_gunlock_q:
1580 	if (da.nr_blocks)
1581 		gfs2_quota_unlock(ndip);
1582 out_gunlock:
1583 	gfs2_dir_no_add(&da);
1584 	if (gfs2_holder_initialized(&rd_gh))
1585 		gfs2_glock_dq_uninit(&rd_gh);
1586 
1587 	while (x--) {
1588 		if (gfs2_holder_queued(ghs + x))
1589 			gfs2_glock_dq(ghs + x);
1590 		gfs2_holder_uninit(ghs + x);
1591 	}
1592 out_gunlock_r:
1593 	if (gfs2_holder_initialized(&r_gh))
1594 		gfs2_glock_dq_uninit(&r_gh);
1595 out:
1596 	gfs2_qa_put(ndip);
1597 	return error;
1598 }
1599 
1600 /**
1601  * gfs2_exchange - exchange two files
1602  * @odir: Parent directory of old file name
1603  * @odentry: The old dentry of the file
1604  * @ndir: Parent directory of new file name
1605  * @ndentry: The new dentry of the file
1606  * @flags: The rename flags
1607  *
1608  * Returns: errno
1609  */
1610 
1611 static int gfs2_exchange(struct inode *odir, struct dentry *odentry,
1612 			 struct inode *ndir, struct dentry *ndentry,
1613 			 unsigned int flags)
1614 {
1615 	struct gfs2_inode *odip = GFS2_I(odir);
1616 	struct gfs2_inode *ndip = GFS2_I(ndir);
1617 	struct gfs2_inode *oip = GFS2_I(odentry->d_inode);
1618 	struct gfs2_inode *nip = GFS2_I(ndentry->d_inode);
1619 	struct gfs2_sbd *sdp = GFS2_SB(odir);
1620 	struct gfs2_holder ghs[4], r_gh;
1621 	unsigned int num_gh;
1622 	unsigned int x;
1623 	umode_t old_mode = oip->i_inode.i_mode;
1624 	umode_t new_mode = nip->i_inode.i_mode;
1625 	int error;
1626 
1627 	gfs2_holder_mark_uninitialized(&r_gh);
1628 	error = gfs2_rindex_update(sdp);
1629 	if (error)
1630 		return error;
1631 
1632 	if (odip != ndip) {
1633 		error = gfs2_glock_nq_init(sdp->sd_rename_gl, LM_ST_EXCLUSIVE,
1634 					   0, &r_gh);
1635 		if (error)
1636 			goto out;
1637 
1638 		if (S_ISDIR(old_mode)) {
1639 			/* don't move a directory into its subdir */
1640 			error = gfs2_ok_to_move(oip, ndip);
1641 			if (error)
1642 				goto out_gunlock_r;
1643 		}
1644 
1645 		if (S_ISDIR(new_mode)) {
1646 			/* don't move a directory into its subdir */
1647 			error = gfs2_ok_to_move(nip, odip);
1648 			if (error)
1649 				goto out_gunlock_r;
1650 		}
1651 	}
1652 
1653 	num_gh = 1;
1654 	gfs2_holder_init(odip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC, ghs);
1655 	if (odip != ndip) {
1656 		gfs2_holder_init(ndip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC,
1657 				 ghs + num_gh);
1658 		num_gh++;
1659 	}
1660 	gfs2_holder_init(oip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC, ghs + num_gh);
1661 	num_gh++;
1662 
1663 	gfs2_holder_init(nip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC, ghs + num_gh);
1664 	num_gh++;
1665 
1666 	for (x = 0; x < num_gh; x++) {
1667 		error = gfs2_glock_nq(ghs + x);
1668 		if (error)
1669 			goto out_gunlock;
1670 	}
1671 
1672 	error = gfs2_glock_async_wait(num_gh, ghs);
1673 	if (error)
1674 		goto out_gunlock;
1675 
1676 	error = -ENOENT;
1677 	if (oip->i_inode.i_nlink == 0 || nip->i_inode.i_nlink == 0)
1678 		goto out_gunlock;
1679 
1680 	error = gfs2_unlink_ok(odip, &odentry->d_name, oip);
1681 	if (error)
1682 		goto out_gunlock;
1683 	error = gfs2_unlink_ok(ndip, &ndentry->d_name, nip);
1684 	if (error)
1685 		goto out_gunlock;
1686 
1687 	if (S_ISDIR(old_mode)) {
1688 		error = gfs2_permission(odentry->d_inode, MAY_WRITE);
1689 		if (error)
1690 			goto out_gunlock;
1691 	}
1692 	if (S_ISDIR(new_mode)) {
1693 		error = gfs2_permission(ndentry->d_inode, MAY_WRITE);
1694 		if (error)
1695 			goto out_gunlock;
1696 	}
1697 	error = gfs2_trans_begin(sdp, 4 * RES_DINODE + 4 * RES_LEAF, 0);
1698 	if (error)
1699 		goto out_gunlock;
1700 
1701 	error = update_moved_ino(oip, ndip, S_ISDIR(old_mode));
1702 	if (error)
1703 		goto out_end_trans;
1704 
1705 	error = update_moved_ino(nip, odip, S_ISDIR(new_mode));
1706 	if (error)
1707 		goto out_end_trans;
1708 
1709 	error = gfs2_dir_mvino(ndip, &ndentry->d_name, oip,
1710 			       IF2DT(old_mode));
1711 	if (error)
1712 		goto out_end_trans;
1713 
1714 	error = gfs2_dir_mvino(odip, &odentry->d_name, nip,
1715 			       IF2DT(new_mode));
1716 	if (error)
1717 		goto out_end_trans;
1718 
1719 	if (odip != ndip) {
1720 		if (S_ISDIR(new_mode) && !S_ISDIR(old_mode)) {
1721 			inc_nlink(&odip->i_inode);
1722 			drop_nlink(&ndip->i_inode);
1723 		} else if (S_ISDIR(old_mode) && !S_ISDIR(new_mode)) {
1724 			inc_nlink(&ndip->i_inode);
1725 			drop_nlink(&odip->i_inode);
1726 		}
1727 	}
1728 	mark_inode_dirty(&ndip->i_inode);
1729 	if (odip != ndip)
1730 		mark_inode_dirty(&odip->i_inode);
1731 
1732 out_end_trans:
1733 	gfs2_trans_end(sdp);
1734 out_gunlock:
1735 	while (x--) {
1736 		if (gfs2_holder_queued(ghs + x))
1737 			gfs2_glock_dq(ghs + x);
1738 		gfs2_holder_uninit(ghs + x);
1739 	}
1740 out_gunlock_r:
1741 	if (gfs2_holder_initialized(&r_gh))
1742 		gfs2_glock_dq_uninit(&r_gh);
1743 out:
1744 	return error;
1745 }
1746 
1747 static int gfs2_rename2(struct inode *odir, struct dentry *odentry,
1748 			struct inode *ndir, struct dentry *ndentry,
1749 			unsigned int flags)
1750 {
1751 	flags &= ~RENAME_NOREPLACE;
1752 
1753 	if (flags & ~RENAME_EXCHANGE)
1754 		return -EINVAL;
1755 
1756 	if (flags & RENAME_EXCHANGE)
1757 		return gfs2_exchange(odir, odentry, ndir, ndentry, flags);
1758 
1759 	return gfs2_rename(odir, odentry, ndir, ndentry);
1760 }
1761 
1762 /**
1763  * gfs2_get_link - Follow a symbolic link
1764  * @dentry: The dentry of the link
1765  * @inode: The inode of the link
1766  * @done: destructor for return value
1767  *
1768  * This can handle symlinks of any size.
1769  *
1770  * Returns: 0 on success or error code
1771  */
1772 
1773 static const char *gfs2_get_link(struct dentry *dentry,
1774 				 struct inode *inode,
1775 				 struct delayed_call *done)
1776 {
1777 	struct gfs2_inode *ip = GFS2_I(inode);
1778 	struct gfs2_holder i_gh;
1779 	struct buffer_head *dibh;
1780 	unsigned int size;
1781 	char *buf;
1782 	int error;
1783 
1784 	if (!dentry)
1785 		return ERR_PTR(-ECHILD);
1786 
1787 	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
1788 	error = gfs2_glock_nq(&i_gh);
1789 	if (error) {
1790 		gfs2_holder_uninit(&i_gh);
1791 		return ERR_PTR(error);
1792 	}
1793 
1794 	size = (unsigned int)i_size_read(&ip->i_inode);
1795 	if (size == 0) {
1796 		gfs2_consist_inode(ip);
1797 		buf = ERR_PTR(-EIO);
1798 		goto out;
1799 	}
1800 
1801 	error = gfs2_meta_inode_buffer(ip, &dibh);
1802 	if (error) {
1803 		buf = ERR_PTR(error);
1804 		goto out;
1805 	}
1806 
1807 	buf = kzalloc(size + 1, GFP_NOFS);
1808 	if (!buf)
1809 		buf = ERR_PTR(-ENOMEM);
1810 	else
1811 		memcpy(buf, dibh->b_data + sizeof(struct gfs2_dinode), size);
1812 	brelse(dibh);
1813 out:
1814 	gfs2_glock_dq_uninit(&i_gh);
1815 	if (!IS_ERR(buf))
1816 		set_delayed_call(done, kfree_link, buf);
1817 	return buf;
1818 }
1819 
1820 /**
1821  * gfs2_permission -
1822  * @inode: The inode
1823  * @mask: The mask to be tested
1824  * @flags: Indicates whether this is an RCU path walk or not
1825  *
1826  * This may be called from the VFS directly, or from within GFS2 with the
1827  * inode locked, so we look to see if the glock is already locked and only
1828  * lock the glock if its not already been done.
1829  *
1830  * Returns: errno
1831  */
1832 
1833 int gfs2_permission(struct inode *inode, int mask)
1834 {
1835 	struct gfs2_inode *ip;
1836 	struct gfs2_holder i_gh;
1837 	int error;
1838 
1839 	gfs2_holder_mark_uninitialized(&i_gh);
1840 	ip = GFS2_I(inode);
1841 	if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
1842 		if (mask & MAY_NOT_BLOCK)
1843 			return -ECHILD;
1844 		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
1845 		if (error)
1846 			return error;
1847 	}
1848 
1849 	if ((mask & MAY_WRITE) && IS_IMMUTABLE(inode))
1850 		error = -EPERM;
1851 	else
1852 		error = generic_permission(inode, mask);
1853 	if (gfs2_holder_initialized(&i_gh))
1854 		gfs2_glock_dq_uninit(&i_gh);
1855 
1856 	return error;
1857 }
1858 
1859 static int __gfs2_setattr_simple(struct inode *inode, struct iattr *attr)
1860 {
1861 	setattr_copy(inode, attr);
1862 	mark_inode_dirty(inode);
1863 	return 0;
1864 }
1865 
1866 /**
1867  * gfs2_setattr_simple -
1868  * @ip:
1869  * @attr:
1870  *
1871  * Returns: errno
1872  */
1873 
1874 int gfs2_setattr_simple(struct inode *inode, struct iattr *attr)
1875 {
1876 	int error;
1877 
1878 	if (current->journal_info)
1879 		return __gfs2_setattr_simple(inode, attr);
1880 
1881 	error = gfs2_trans_begin(GFS2_SB(inode), RES_DINODE, 0);
1882 	if (error)
1883 		return error;
1884 
1885 	error = __gfs2_setattr_simple(inode, attr);
1886 	gfs2_trans_end(GFS2_SB(inode));
1887 	return error;
1888 }
1889 
1890 static int setattr_chown(struct inode *inode, struct iattr *attr)
1891 {
1892 	struct gfs2_inode *ip = GFS2_I(inode);
1893 	struct gfs2_sbd *sdp = GFS2_SB(inode);
1894 	kuid_t ouid, nuid;
1895 	kgid_t ogid, ngid;
1896 	int error;
1897 	struct gfs2_alloc_parms ap;
1898 
1899 	ouid = inode->i_uid;
1900 	ogid = inode->i_gid;
1901 	nuid = attr->ia_uid;
1902 	ngid = attr->ia_gid;
1903 
1904 	if (!(attr->ia_valid & ATTR_UID) || uid_eq(ouid, nuid))
1905 		ouid = nuid = NO_UID_QUOTA_CHANGE;
1906 	if (!(attr->ia_valid & ATTR_GID) || gid_eq(ogid, ngid))
1907 		ogid = ngid = NO_GID_QUOTA_CHANGE;
1908 	error = gfs2_qa_get(ip);
1909 	if (error)
1910 		return error;
1911 
1912 	error = gfs2_rindex_update(sdp);
1913 	if (error)
1914 		goto out;
1915 
1916 	error = gfs2_quota_lock(ip, nuid, ngid);
1917 	if (error)
1918 		goto out;
1919 
1920 	ap.target = gfs2_get_inode_blocks(&ip->i_inode);
1921 
1922 	if (!uid_eq(ouid, NO_UID_QUOTA_CHANGE) ||
1923 	    !gid_eq(ogid, NO_GID_QUOTA_CHANGE)) {
1924 		error = gfs2_quota_check(ip, nuid, ngid, &ap);
1925 		if (error)
1926 			goto out_gunlock_q;
1927 	}
1928 
1929 	error = gfs2_trans_begin(sdp, RES_DINODE + 2 * RES_QUOTA, 0);
1930 	if (error)
1931 		goto out_gunlock_q;
1932 
1933 	error = gfs2_setattr_simple(inode, attr);
1934 	if (error)
1935 		goto out_end_trans;
1936 
1937 	if (!uid_eq(ouid, NO_UID_QUOTA_CHANGE) ||
1938 	    !gid_eq(ogid, NO_GID_QUOTA_CHANGE)) {
1939 		gfs2_quota_change(ip, -(s64)ap.target, ouid, ogid);
1940 		gfs2_quota_change(ip, ap.target, nuid, ngid);
1941 	}
1942 
1943 out_end_trans:
1944 	gfs2_trans_end(sdp);
1945 out_gunlock_q:
1946 	gfs2_quota_unlock(ip);
1947 out:
1948 	gfs2_qa_put(ip);
1949 	return error;
1950 }
1951 
1952 /**
1953  * gfs2_setattr - Change attributes on an inode
1954  * @dentry: The dentry which is changing
1955  * @attr: The structure describing the change
1956  *
1957  * The VFS layer wants to change one or more of an inodes attributes.  Write
1958  * that change out to disk.
1959  *
1960  * Returns: errno
1961  */
1962 
1963 static int gfs2_setattr(struct dentry *dentry, struct iattr *attr)
1964 {
1965 	struct inode *inode = d_inode(dentry);
1966 	struct gfs2_inode *ip = GFS2_I(inode);
1967 	struct gfs2_holder i_gh;
1968 	int error;
1969 
1970 	error = gfs2_qa_get(ip);
1971 	if (error)
1972 		return error;
1973 
1974 	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1975 	if (error)
1976 		goto out;
1977 
1978 	error = -EPERM;
1979 	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
1980 		goto error;
1981 
1982 	error = setattr_prepare(dentry, attr);
1983 	if (error)
1984 		goto error;
1985 
1986 	if (attr->ia_valid & ATTR_SIZE)
1987 		error = gfs2_setattr_size(inode, attr->ia_size);
1988 	else if (attr->ia_valid & (ATTR_UID | ATTR_GID))
1989 		error = setattr_chown(inode, attr);
1990 	else {
1991 		error = gfs2_setattr_simple(inode, attr);
1992 		if (!error && attr->ia_valid & ATTR_MODE)
1993 			error = posix_acl_chmod(inode, inode->i_mode);
1994 	}
1995 
1996 error:
1997 	if (!error)
1998 		mark_inode_dirty(inode);
1999 	gfs2_glock_dq_uninit(&i_gh);
2000 out:
2001 	gfs2_qa_put(ip);
2002 	return error;
2003 }
2004 
2005 /**
2006  * gfs2_getattr - Read out an inode's attributes
2007  * @path: Object to query
2008  * @stat: The inode's stats
2009  * @request_mask: Mask of STATX_xxx flags indicating the caller's interests
2010  * @flags: AT_STATX_xxx setting
2011  *
2012  * This may be called from the VFS directly, or from within GFS2 with the
2013  * inode locked, so we look to see if the glock is already locked and only
2014  * lock the glock if its not already been done. Note that its the NFS
2015  * readdirplus operation which causes this to be called (from filldir)
2016  * with the glock already held.
2017  *
2018  * Returns: errno
2019  */
2020 
2021 static int gfs2_getattr(const struct path *path, struct kstat *stat,
2022 			u32 request_mask, unsigned int flags)
2023 {
2024 	struct inode *inode = d_inode(path->dentry);
2025 	struct gfs2_inode *ip = GFS2_I(inode);
2026 	struct gfs2_holder gh;
2027 	u32 gfsflags;
2028 	int error;
2029 
2030 	gfs2_holder_mark_uninitialized(&gh);
2031 	if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
2032 		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
2033 		if (error)
2034 			return error;
2035 	}
2036 
2037 	gfsflags = ip->i_diskflags;
2038 	if (gfsflags & GFS2_DIF_APPENDONLY)
2039 		stat->attributes |= STATX_ATTR_APPEND;
2040 	if (gfsflags & GFS2_DIF_IMMUTABLE)
2041 		stat->attributes |= STATX_ATTR_IMMUTABLE;
2042 
2043 	stat->attributes_mask |= (STATX_ATTR_APPEND |
2044 				  STATX_ATTR_COMPRESSED |
2045 				  STATX_ATTR_ENCRYPTED |
2046 				  STATX_ATTR_IMMUTABLE |
2047 				  STATX_ATTR_NODUMP);
2048 
2049 	generic_fillattr(inode, stat);
2050 
2051 	if (gfs2_holder_initialized(&gh))
2052 		gfs2_glock_dq_uninit(&gh);
2053 
2054 	return 0;
2055 }
2056 
2057 static int gfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2058 		       u64 start, u64 len)
2059 {
2060 	struct gfs2_inode *ip = GFS2_I(inode);
2061 	struct gfs2_holder gh;
2062 	int ret;
2063 
2064 	inode_lock_shared(inode);
2065 
2066 	ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
2067 	if (ret)
2068 		goto out;
2069 
2070 	ret = iomap_fiemap(inode, fieinfo, start, len, &gfs2_iomap_ops);
2071 
2072 	gfs2_glock_dq_uninit(&gh);
2073 
2074 out:
2075 	inode_unlock_shared(inode);
2076 	return ret;
2077 }
2078 
2079 loff_t gfs2_seek_data(struct file *file, loff_t offset)
2080 {
2081 	struct inode *inode = file->f_mapping->host;
2082 	struct gfs2_inode *ip = GFS2_I(inode);
2083 	struct gfs2_holder gh;
2084 	loff_t ret;
2085 
2086 	inode_lock_shared(inode);
2087 	ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
2088 	if (!ret)
2089 		ret = iomap_seek_data(inode, offset, &gfs2_iomap_ops);
2090 	gfs2_glock_dq_uninit(&gh);
2091 	inode_unlock_shared(inode);
2092 
2093 	if (ret < 0)
2094 		return ret;
2095 	return vfs_setpos(file, ret, inode->i_sb->s_maxbytes);
2096 }
2097 
2098 loff_t gfs2_seek_hole(struct file *file, loff_t offset)
2099 {
2100 	struct inode *inode = file->f_mapping->host;
2101 	struct gfs2_inode *ip = GFS2_I(inode);
2102 	struct gfs2_holder gh;
2103 	loff_t ret;
2104 
2105 	inode_lock_shared(inode);
2106 	ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
2107 	if (!ret)
2108 		ret = iomap_seek_hole(inode, offset, &gfs2_iomap_ops);
2109 	gfs2_glock_dq_uninit(&gh);
2110 	inode_unlock_shared(inode);
2111 
2112 	if (ret < 0)
2113 		return ret;
2114 	return vfs_setpos(file, ret, inode->i_sb->s_maxbytes);
2115 }
2116 
2117 const struct inode_operations gfs2_file_iops = {
2118 	.permission = gfs2_permission,
2119 	.setattr = gfs2_setattr,
2120 	.getattr = gfs2_getattr,
2121 	.listxattr = gfs2_listxattr,
2122 	.fiemap = gfs2_fiemap,
2123 	.get_acl = gfs2_get_acl,
2124 	.set_acl = gfs2_set_acl,
2125 };
2126 
2127 const struct inode_operations gfs2_dir_iops = {
2128 	.create = gfs2_create,
2129 	.lookup = gfs2_lookup,
2130 	.link = gfs2_link,
2131 	.unlink = gfs2_unlink,
2132 	.symlink = gfs2_symlink,
2133 	.mkdir = gfs2_mkdir,
2134 	.rmdir = gfs2_unlink,
2135 	.mknod = gfs2_mknod,
2136 	.rename = gfs2_rename2,
2137 	.permission = gfs2_permission,
2138 	.setattr = gfs2_setattr,
2139 	.getattr = gfs2_getattr,
2140 	.listxattr = gfs2_listxattr,
2141 	.fiemap = gfs2_fiemap,
2142 	.get_acl = gfs2_get_acl,
2143 	.set_acl = gfs2_set_acl,
2144 	.atomic_open = gfs2_atomic_open,
2145 };
2146 
2147 const struct inode_operations gfs2_symlink_iops = {
2148 	.get_link = gfs2_get_link,
2149 	.permission = gfs2_permission,
2150 	.setattr = gfs2_setattr,
2151 	.getattr = gfs2_getattr,
2152 	.listxattr = gfs2_listxattr,
2153 	.fiemap = gfs2_fiemap,
2154 };
2155 
2156