xref: /linux/fs/gfs2/inode.c (revision b1a54551dd9ed5ef1763b97b35a0999ca002b95c)
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 const struct inode_operations gfs2_file_iops;
40 static const struct inode_operations gfs2_dir_iops;
41 static const struct inode_operations gfs2_symlink_iops;
42 
43 /**
44  * gfs2_set_iop - Sets inode operations
45  * @inode: The inode with correct i_mode filled in
46  *
47  * GFS2 lookup code fills in vfs inode contents based on info obtained
48  * from directory entry inside gfs2_inode_lookup().
49  */
50 
51 static void gfs2_set_iop(struct inode *inode)
52 {
53 	struct gfs2_sbd *sdp = GFS2_SB(inode);
54 	umode_t mode = inode->i_mode;
55 
56 	if (S_ISREG(mode)) {
57 		inode->i_op = &gfs2_file_iops;
58 		if (gfs2_localflocks(sdp))
59 			inode->i_fop = &gfs2_file_fops_nolock;
60 		else
61 			inode->i_fop = &gfs2_file_fops;
62 	} else if (S_ISDIR(mode)) {
63 		inode->i_op = &gfs2_dir_iops;
64 		if (gfs2_localflocks(sdp))
65 			inode->i_fop = &gfs2_dir_fops_nolock;
66 		else
67 			inode->i_fop = &gfs2_dir_fops;
68 	} else if (S_ISLNK(mode)) {
69 		inode->i_op = &gfs2_symlink_iops;
70 	} else {
71 		inode->i_op = &gfs2_file_iops;
72 		init_special_inode(inode, inode->i_mode, inode->i_rdev);
73 	}
74 }
75 
76 static int iget_test(struct inode *inode, void *opaque)
77 {
78 	u64 no_addr = *(u64 *)opaque;
79 
80 	return GFS2_I(inode)->i_no_addr == no_addr;
81 }
82 
83 static int iget_set(struct inode *inode, void *opaque)
84 {
85 	u64 no_addr = *(u64 *)opaque;
86 
87 	GFS2_I(inode)->i_no_addr = no_addr;
88 	inode->i_ino = no_addr;
89 	return 0;
90 }
91 
92 /**
93  * gfs2_inode_lookup - Lookup an inode
94  * @sb: The super block
95  * @type: The type of the inode
96  * @no_addr: The inode number
97  * @no_formal_ino: The inode generation number
98  * @blktype: Requested block type (GFS2_BLKST_DINODE or GFS2_BLKST_UNLINKED;
99  *           GFS2_BLKST_FREE to indicate not to verify)
100  *
101  * If @type is DT_UNKNOWN, the inode type is fetched from disk.
102  *
103  * If @blktype is anything other than GFS2_BLKST_FREE (which is used as a
104  * placeholder because it doesn't otherwise make sense), the on-disk block type
105  * is verified to be @blktype.
106  *
107  * When @no_formal_ino is non-zero, this function will return ERR_PTR(-ESTALE)
108  * if it detects that @no_formal_ino doesn't match the actual inode generation
109  * number.  However, it doesn't always know unless @type is DT_UNKNOWN.
110  *
111  * Returns: A VFS inode, or an error
112  */
113 
114 struct inode *gfs2_inode_lookup(struct super_block *sb, unsigned int type,
115 				u64 no_addr, u64 no_formal_ino,
116 				unsigned int blktype)
117 {
118 	struct inode *inode;
119 	struct gfs2_inode *ip;
120 	struct gfs2_holder i_gh;
121 	int error;
122 
123 	gfs2_holder_mark_uninitialized(&i_gh);
124 	inode = iget5_locked(sb, no_addr, iget_test, iget_set, &no_addr);
125 	if (!inode)
126 		return ERR_PTR(-ENOMEM);
127 
128 	ip = GFS2_I(inode);
129 
130 	if (inode->i_state & I_NEW) {
131 		struct gfs2_sbd *sdp = GFS2_SB(inode);
132 		struct gfs2_glock *io_gl;
133 		int extra_flags = 0;
134 
135 		error = gfs2_glock_get(sdp, no_addr, &gfs2_inode_glops, CREATE,
136 				       &ip->i_gl);
137 		if (unlikely(error))
138 			goto fail;
139 
140 		error = gfs2_glock_get(sdp, no_addr, &gfs2_iopen_glops, CREATE,
141 				       &io_gl);
142 		if (unlikely(error))
143 			goto fail;
144 
145 		/*
146 		 * The only caller that sets @blktype to GFS2_BLKST_UNLINKED is
147 		 * delete_work_func().  Make sure not to cancel the delete work
148 		 * from within itself here.
149 		 */
150 		if (blktype == GFS2_BLKST_UNLINKED)
151 			extra_flags |= LM_FLAG_TRY;
152 		else
153 			gfs2_cancel_delete_work(io_gl);
154 		error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED,
155 					   GL_EXACT | GL_NOPID | extra_flags,
156 					   &ip->i_iopen_gh);
157 		gfs2_glock_put(io_gl);
158 		if (unlikely(error))
159 			goto fail;
160 
161 		if (type == DT_UNKNOWN || blktype != GFS2_BLKST_FREE) {
162 			/*
163 			 * The GL_SKIP flag indicates to skip reading the inode
164 			 * block.  We read the inode when instantiating it
165 			 * after possibly checking the block type.
166 			 */
167 			error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE,
168 						   GL_SKIP, &i_gh);
169 			if (error)
170 				goto fail;
171 
172 			error = -ESTALE;
173 			if (no_formal_ino &&
174 			    gfs2_inode_already_deleted(ip->i_gl, no_formal_ino))
175 				goto fail;
176 
177 			if (blktype != GFS2_BLKST_FREE) {
178 				error = gfs2_check_blk_type(sdp, no_addr,
179 							    blktype);
180 				if (error)
181 					goto fail;
182 			}
183 		}
184 
185 		set_bit(GLF_INSTANTIATE_NEEDED, &ip->i_gl->gl_flags);
186 
187 		/* Lowest possible timestamp; will be overwritten in gfs2_dinode_in. */
188 		inode_set_atime(inode,
189 				1LL << (8 * sizeof(inode_get_atime_sec(inode)) - 1),
190 				0);
191 
192 		glock_set_object(ip->i_gl, ip);
193 
194 		if (type == DT_UNKNOWN) {
195 			/* Inode glock must be locked already */
196 			error = gfs2_instantiate(&i_gh);
197 			if (error) {
198 				glock_clear_object(ip->i_gl, ip);
199 				goto fail;
200 			}
201 		} else {
202 			ip->i_no_formal_ino = no_formal_ino;
203 			inode->i_mode = DT2IF(type);
204 		}
205 
206 		if (gfs2_holder_initialized(&i_gh))
207 			gfs2_glock_dq_uninit(&i_gh);
208 		glock_set_object(ip->i_iopen_gh.gh_gl, ip);
209 
210 		gfs2_set_iop(inode);
211 		unlock_new_inode(inode);
212 	}
213 
214 	if (no_formal_ino && ip->i_no_formal_ino &&
215 	    no_formal_ino != ip->i_no_formal_ino) {
216 		iput(inode);
217 		return ERR_PTR(-ESTALE);
218 	}
219 
220 	return inode;
221 
222 fail:
223 	if (error == GLR_TRYFAILED)
224 		error = -EAGAIN;
225 	if (gfs2_holder_initialized(&ip->i_iopen_gh))
226 		gfs2_glock_dq_uninit(&ip->i_iopen_gh);
227 	if (gfs2_holder_initialized(&i_gh))
228 		gfs2_glock_dq_uninit(&i_gh);
229 	if (ip->i_gl) {
230 		gfs2_glock_put(ip->i_gl);
231 		ip->i_gl = NULL;
232 	}
233 	iget_failed(inode);
234 	return ERR_PTR(error);
235 }
236 
237 /**
238  * gfs2_lookup_by_inum - look up an inode by inode number
239  * @sdp: The super block
240  * @no_addr: The inode number
241  * @no_formal_ino: The inode generation number (0 for any)
242  * @blktype: Requested block type (see gfs2_inode_lookup)
243  */
244 struct inode *gfs2_lookup_by_inum(struct gfs2_sbd *sdp, u64 no_addr,
245 				  u64 no_formal_ino, unsigned int blktype)
246 {
247 	struct super_block *sb = sdp->sd_vfs;
248 	struct inode *inode;
249 	int error;
250 
251 	inode = gfs2_inode_lookup(sb, DT_UNKNOWN, no_addr, no_formal_ino,
252 				  blktype);
253 	if (IS_ERR(inode))
254 		return inode;
255 
256 	if (no_formal_ino) {
257 		error = -EIO;
258 		if (GFS2_I(inode)->i_diskflags & GFS2_DIF_SYSTEM)
259 			goto fail_iput;
260 	}
261 	return inode;
262 
263 fail_iput:
264 	iput(inode);
265 	return ERR_PTR(error);
266 }
267 
268 
269 /**
270  * gfs2_lookup_meta - Look up an inode in a metadata directory
271  * @dip: The directory
272  * @name: The name of the inode
273  */
274 struct inode *gfs2_lookup_meta(struct inode *dip, const char *name)
275 {
276 	struct qstr qstr;
277 	struct inode *inode;
278 
279 	gfs2_str2qstr(&qstr, name);
280 	inode = gfs2_lookupi(dip, &qstr, 1);
281 	if (IS_ERR_OR_NULL(inode))
282 		return inode ? inode : ERR_PTR(-ENOENT);
283 
284 	/*
285 	 * Must not call back into the filesystem when allocating
286 	 * pages in the metadata inode's address space.
287 	 */
288 	mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS);
289 
290 	return inode;
291 }
292 
293 
294 /**
295  * gfs2_lookupi - Look up a filename in a directory and return its inode
296  * @dir: The inode of the directory containing the inode to look-up
297  * @name: The name of the inode to look for
298  * @is_root: If 1, ignore the caller's permissions
299  *
300  * This can be called via the VFS filldir function when NFS is doing
301  * a readdirplus and the inode which its intending to stat isn't
302  * already in cache. In this case we must not take the directory glock
303  * again, since the readdir call will have already taken that lock.
304  *
305  * Returns: errno
306  */
307 
308 struct inode *gfs2_lookupi(struct inode *dir, const struct qstr *name,
309 			   int is_root)
310 {
311 	struct super_block *sb = dir->i_sb;
312 	struct gfs2_inode *dip = GFS2_I(dir);
313 	struct gfs2_holder d_gh;
314 	int error = 0;
315 	struct inode *inode = NULL;
316 
317 	gfs2_holder_mark_uninitialized(&d_gh);
318 	if (!name->len || name->len > GFS2_FNAMESIZE)
319 		return ERR_PTR(-ENAMETOOLONG);
320 
321 	if ((name->len == 1 && memcmp(name->name, ".", 1) == 0) ||
322 	    (name->len == 2 && memcmp(name->name, "..", 2) == 0 &&
323 	     dir == d_inode(sb->s_root))) {
324 		igrab(dir);
325 		return dir;
326 	}
327 
328 	if (gfs2_glock_is_locked_by_me(dip->i_gl) == NULL) {
329 		error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh);
330 		if (error)
331 			return ERR_PTR(error);
332 	}
333 
334 	if (!is_root) {
335 		error = gfs2_permission(&nop_mnt_idmap, dir, MAY_EXEC);
336 		if (error)
337 			goto out;
338 	}
339 
340 	inode = gfs2_dir_search(dir, name, false);
341 	if (IS_ERR(inode))
342 		error = PTR_ERR(inode);
343 out:
344 	if (gfs2_holder_initialized(&d_gh))
345 		gfs2_glock_dq_uninit(&d_gh);
346 	if (error == -ENOENT)
347 		return NULL;
348 	return inode ? inode : ERR_PTR(error);
349 }
350 
351 /**
352  * create_ok - OK to create a new on-disk inode here?
353  * @dip:  Directory in which dinode is to be created
354  * @name:  Name of new dinode
355  * @mode:
356  *
357  * Returns: errno
358  */
359 
360 static int create_ok(struct gfs2_inode *dip, const struct qstr *name,
361 		     umode_t mode)
362 {
363 	int error;
364 
365 	error = gfs2_permission(&nop_mnt_idmap, &dip->i_inode,
366 				MAY_WRITE | MAY_EXEC);
367 	if (error)
368 		return error;
369 
370 	/*  Don't create entries in an unlinked directory  */
371 	if (!dip->i_inode.i_nlink)
372 		return -ENOENT;
373 
374 	if (dip->i_entries == (u32)-1)
375 		return -EFBIG;
376 	if (S_ISDIR(mode) && dip->i_inode.i_nlink == (u32)-1)
377 		return -EMLINK;
378 
379 	return 0;
380 }
381 
382 static void munge_mode_uid_gid(const struct gfs2_inode *dip,
383 			       struct inode *inode)
384 {
385 	if (GFS2_SB(&dip->i_inode)->sd_args.ar_suiddir &&
386 	    (dip->i_inode.i_mode & S_ISUID) &&
387 	    !uid_eq(dip->i_inode.i_uid, GLOBAL_ROOT_UID)) {
388 		if (S_ISDIR(inode->i_mode))
389 			inode->i_mode |= S_ISUID;
390 		else if (!uid_eq(dip->i_inode.i_uid, current_fsuid()))
391 			inode->i_mode &= ~07111;
392 		inode->i_uid = dip->i_inode.i_uid;
393 	} else
394 		inode->i_uid = current_fsuid();
395 
396 	if (dip->i_inode.i_mode & S_ISGID) {
397 		if (S_ISDIR(inode->i_mode))
398 			inode->i_mode |= S_ISGID;
399 		inode->i_gid = dip->i_inode.i_gid;
400 	} else
401 		inode->i_gid = current_fsgid();
402 }
403 
404 static int alloc_dinode(struct gfs2_inode *ip, u32 flags, unsigned *dblocks)
405 {
406 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
407 	struct gfs2_alloc_parms ap = { .target = *dblocks, .aflags = flags, };
408 	int error;
409 
410 	error = gfs2_quota_lock_check(ip, &ap);
411 	if (error)
412 		goto out;
413 
414 	error = gfs2_inplace_reserve(ip, &ap);
415 	if (error)
416 		goto out_quota;
417 
418 	error = gfs2_trans_begin(sdp, (*dblocks * RES_RG_BIT) + RES_STATFS + RES_QUOTA, 0);
419 	if (error)
420 		goto out_ipreserv;
421 
422 	error = gfs2_alloc_blocks(ip, &ip->i_no_addr, dblocks, 1);
423 	if (error)
424 		goto out_trans_end;
425 
426 	ip->i_no_formal_ino = ip->i_generation;
427 	ip->i_inode.i_ino = ip->i_no_addr;
428 	ip->i_goal = ip->i_no_addr;
429 	if (*dblocks > 1)
430 		ip->i_eattr = ip->i_no_addr + 1;
431 
432 out_trans_end:
433 	gfs2_trans_end(sdp);
434 out_ipreserv:
435 	gfs2_inplace_release(ip);
436 out_quota:
437 	gfs2_quota_unlock(ip);
438 out:
439 	return error;
440 }
441 
442 static void gfs2_init_dir(struct buffer_head *dibh,
443 			  const struct gfs2_inode *parent)
444 {
445 	struct gfs2_dinode *di = (struct gfs2_dinode *)dibh->b_data;
446 	struct gfs2_dirent *dent = (struct gfs2_dirent *)(di+1);
447 
448 	gfs2_qstr2dirent(&gfs2_qdot, GFS2_DIRENT_SIZE(gfs2_qdot.len), dent);
449 	dent->de_inum = di->di_num; /* already GFS2 endian */
450 	dent->de_type = cpu_to_be16(DT_DIR);
451 
452 	dent = (struct gfs2_dirent *)((char*)dent + GFS2_DIRENT_SIZE(1));
453 	gfs2_qstr2dirent(&gfs2_qdotdot, dibh->b_size - GFS2_DIRENT_SIZE(1) - sizeof(struct gfs2_dinode), dent);
454 	gfs2_inum_out(parent, dent);
455 	dent->de_type = cpu_to_be16(DT_DIR);
456 
457 }
458 
459 /**
460  * gfs2_init_xattr - Initialise an xattr block for a new inode
461  * @ip: The inode in question
462  *
463  * This sets up an empty xattr block for a new inode, ready to
464  * take any ACLs, LSM xattrs, etc.
465  */
466 
467 static void gfs2_init_xattr(struct gfs2_inode *ip)
468 {
469 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
470 	struct buffer_head *bh;
471 	struct gfs2_ea_header *ea;
472 
473 	bh = gfs2_meta_new(ip->i_gl, ip->i_eattr);
474 	gfs2_trans_add_meta(ip->i_gl, bh);
475 	gfs2_metatype_set(bh, GFS2_METATYPE_EA, GFS2_FORMAT_EA);
476 	gfs2_buffer_clear_tail(bh, sizeof(struct gfs2_meta_header));
477 
478 	ea = GFS2_EA_BH2FIRST(bh);
479 	ea->ea_rec_len = cpu_to_be32(sdp->sd_jbsize);
480 	ea->ea_type = GFS2_EATYPE_UNUSED;
481 	ea->ea_flags = GFS2_EAFLAG_LAST;
482 
483 	brelse(bh);
484 }
485 
486 /**
487  * init_dinode - Fill in a new dinode structure
488  * @dip: The directory this inode is being created in
489  * @ip: The inode
490  * @symname: The symlink destination (if a symlink)
491  *
492  */
493 
494 static void init_dinode(struct gfs2_inode *dip, struct gfs2_inode *ip,
495 			const char *symname)
496 {
497 	struct gfs2_dinode *di;
498 	struct buffer_head *dibh;
499 
500 	dibh = gfs2_meta_new(ip->i_gl, ip->i_no_addr);
501 	gfs2_trans_add_meta(ip->i_gl, dibh);
502 	di = (struct gfs2_dinode *)dibh->b_data;
503 	gfs2_dinode_out(ip, di);
504 
505 	di->di_major = cpu_to_be32(imajor(&ip->i_inode));
506 	di->di_minor = cpu_to_be32(iminor(&ip->i_inode));
507 	di->__pad1 = 0;
508 	di->__pad2 = 0;
509 	di->__pad3 = 0;
510 	memset(&di->__pad4, 0, sizeof(di->__pad4));
511 	memset(&di->di_reserved, 0, sizeof(di->di_reserved));
512 	gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
513 
514 	switch(ip->i_inode.i_mode & S_IFMT) {
515 	case S_IFDIR:
516 		gfs2_init_dir(dibh, dip);
517 		break;
518 	case S_IFLNK:
519 		memcpy(dibh->b_data + sizeof(struct gfs2_dinode), symname, ip->i_inode.i_size);
520 		break;
521 	}
522 
523 	set_buffer_uptodate(dibh);
524 	brelse(dibh);
525 }
526 
527 /**
528  * gfs2_trans_da_blks - Calculate number of blocks to link inode
529  * @dip: The directory we are linking into
530  * @da: The dir add information
531  * @nr_inodes: The number of inodes involved
532  *
533  * This calculate the number of blocks we need to reserve in a
534  * transaction to link @nr_inodes into a directory. In most cases
535  * @nr_inodes will be 2 (the directory plus the inode being linked in)
536  * but in case of rename, 4 may be required.
537  *
538  * Returns: Number of blocks
539  */
540 
541 static unsigned gfs2_trans_da_blks(const struct gfs2_inode *dip,
542 				   const struct gfs2_diradd *da,
543 				   unsigned nr_inodes)
544 {
545 	return da->nr_blocks + gfs2_rg_blocks(dip, da->nr_blocks) +
546 	       (nr_inodes * RES_DINODE) + RES_QUOTA + RES_STATFS;
547 }
548 
549 static int link_dinode(struct gfs2_inode *dip, const struct qstr *name,
550 		       struct gfs2_inode *ip, struct gfs2_diradd *da)
551 {
552 	struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
553 	struct gfs2_alloc_parms ap = { .target = da->nr_blocks, };
554 	int error;
555 
556 	if (da->nr_blocks) {
557 		error = gfs2_quota_lock_check(dip, &ap);
558 		if (error)
559 			goto fail_quota_locks;
560 
561 		error = gfs2_inplace_reserve(dip, &ap);
562 		if (error)
563 			goto fail_quota_locks;
564 
565 		error = gfs2_trans_begin(sdp, gfs2_trans_da_blks(dip, da, 2), 0);
566 		if (error)
567 			goto fail_ipreserv;
568 	} else {
569 		error = gfs2_trans_begin(sdp, RES_LEAF + 2 * RES_DINODE, 0);
570 		if (error)
571 			goto fail_quota_locks;
572 	}
573 
574 	error = gfs2_dir_add(&dip->i_inode, name, ip, da);
575 
576 	gfs2_trans_end(sdp);
577 fail_ipreserv:
578 	gfs2_inplace_release(dip);
579 fail_quota_locks:
580 	gfs2_quota_unlock(dip);
581 	return error;
582 }
583 
584 static int gfs2_initxattrs(struct inode *inode, const struct xattr *xattr_array,
585 		    void *fs_info)
586 {
587 	const struct xattr *xattr;
588 	int err = 0;
589 
590 	for (xattr = xattr_array; xattr->name != NULL; xattr++) {
591 		err = __gfs2_xattr_set(inode, xattr->name, xattr->value,
592 				       xattr->value_len, 0,
593 				       GFS2_EATYPE_SECURITY);
594 		if (err < 0)
595 			break;
596 	}
597 	return err;
598 }
599 
600 /**
601  * gfs2_create_inode - Create a new inode
602  * @dir: The parent directory
603  * @dentry: The new dentry
604  * @file: If non-NULL, the file which is being opened
605  * @mode: The permissions on the new inode
606  * @dev: For device nodes, this is the device number
607  * @symname: For symlinks, this is the link destination
608  * @size: The initial size of the inode (ignored for directories)
609  * @excl: Force fail if inode exists
610  *
611  * FIXME: Change to allocate the disk blocks and write them out in the same
612  * transaction.  That way, we can no longer end up in a situation in which an
613  * inode is allocated, the node crashes, and the block looks like a valid
614  * inode.  (With atomic creates in place, we will also no longer need to zero
615  * the link count and dirty the inode here on failure.)
616  *
617  * Returns: 0 on success, or error code
618  */
619 
620 static int gfs2_create_inode(struct inode *dir, struct dentry *dentry,
621 			     struct file *file,
622 			     umode_t mode, dev_t dev, const char *symname,
623 			     unsigned int size, int excl)
624 {
625 	const struct qstr *name = &dentry->d_name;
626 	struct posix_acl *default_acl, *acl;
627 	struct gfs2_holder d_gh, gh;
628 	struct inode *inode = NULL;
629 	struct gfs2_inode *dip = GFS2_I(dir), *ip;
630 	struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
631 	struct gfs2_glock *io_gl;
632 	int error;
633 	u32 aflags = 0;
634 	unsigned blocks = 1;
635 	struct gfs2_diradd da = { .bh = NULL, .save_loc = 1, };
636 
637 	if (!name->len || name->len > GFS2_FNAMESIZE)
638 		return -ENAMETOOLONG;
639 
640 	error = gfs2_qa_get(dip);
641 	if (error)
642 		return error;
643 
644 	error = gfs2_rindex_update(sdp);
645 	if (error)
646 		goto fail;
647 
648 	error = gfs2_glock_nq_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, &d_gh);
649 	if (error)
650 		goto fail;
651 	gfs2_holder_mark_uninitialized(&gh);
652 
653 	error = create_ok(dip, name, mode);
654 	if (error)
655 		goto fail_gunlock;
656 
657 	inode = gfs2_dir_search(dir, &dentry->d_name, !S_ISREG(mode) || excl);
658 	error = PTR_ERR(inode);
659 	if (!IS_ERR(inode)) {
660 		if (S_ISDIR(inode->i_mode)) {
661 			iput(inode);
662 			inode = ERR_PTR(-EISDIR);
663 			goto fail_gunlock;
664 		}
665 		d_instantiate(dentry, inode);
666 		error = 0;
667 		if (file) {
668 			if (S_ISREG(inode->i_mode))
669 				error = finish_open(file, dentry, gfs2_open_common);
670 			else
671 				error = finish_no_open(file, NULL);
672 		}
673 		gfs2_glock_dq_uninit(&d_gh);
674 		goto fail;
675 	} else if (error != -ENOENT) {
676 		goto fail_gunlock;
677 	}
678 
679 	error = gfs2_diradd_alloc_required(dir, name, &da);
680 	if (error < 0)
681 		goto fail_gunlock;
682 
683 	inode = new_inode(sdp->sd_vfs);
684 	error = -ENOMEM;
685 	if (!inode)
686 		goto fail_gunlock;
687 	ip = GFS2_I(inode);
688 
689 	error = posix_acl_create(dir, &mode, &default_acl, &acl);
690 	if (error)
691 		goto fail_gunlock;
692 
693 	error = gfs2_qa_get(ip);
694 	if (error)
695 		goto fail_free_acls;
696 
697 	inode->i_mode = mode;
698 	set_nlink(inode, S_ISDIR(mode) ? 2 : 1);
699 	inode->i_rdev = dev;
700 	inode->i_size = size;
701 	simple_inode_init_ts(inode);
702 	munge_mode_uid_gid(dip, inode);
703 	check_and_update_goal(dip);
704 	ip->i_goal = dip->i_goal;
705 	ip->i_diskflags = 0;
706 	ip->i_eattr = 0;
707 	ip->i_height = 0;
708 	ip->i_depth = 0;
709 	ip->i_entries = 0;
710 	ip->i_no_addr = 0; /* Temporarily zero until real addr is assigned */
711 
712 	switch(mode & S_IFMT) {
713 	case S_IFREG:
714 		if ((dip->i_diskflags & GFS2_DIF_INHERIT_JDATA) ||
715 		    gfs2_tune_get(sdp, gt_new_files_jdata))
716 			ip->i_diskflags |= GFS2_DIF_JDATA;
717 		gfs2_set_aops(inode);
718 		break;
719 	case S_IFDIR:
720 		ip->i_diskflags |= (dip->i_diskflags & GFS2_DIF_INHERIT_JDATA);
721 		ip->i_diskflags |= GFS2_DIF_JDATA;
722 		ip->i_entries = 2;
723 		break;
724 	}
725 
726 	/* Force SYSTEM flag on all files and subdirs of a SYSTEM directory */
727 	if (dip->i_diskflags & GFS2_DIF_SYSTEM)
728 		ip->i_diskflags |= GFS2_DIF_SYSTEM;
729 
730 	gfs2_set_inode_flags(inode);
731 
732 	if ((GFS2_I(d_inode(sdp->sd_root_dir)) == dip) ||
733 	    (dip->i_diskflags & GFS2_DIF_TOPDIR))
734 		aflags |= GFS2_AF_ORLOV;
735 
736 	if (default_acl || acl)
737 		blocks++;
738 
739 	error = alloc_dinode(ip, aflags, &blocks);
740 	if (error)
741 		goto fail_free_inode;
742 
743 	gfs2_set_inode_blocks(inode, blocks);
744 
745 	error = gfs2_glock_get(sdp, ip->i_no_addr, &gfs2_inode_glops, CREATE, &ip->i_gl);
746 	if (error)
747 		goto fail_free_inode;
748 
749 	error = gfs2_glock_get(sdp, ip->i_no_addr, &gfs2_iopen_glops, CREATE, &io_gl);
750 	if (error)
751 		goto fail_free_inode;
752 	gfs2_cancel_delete_work(io_gl);
753 
754 retry:
755 	error = insert_inode_locked4(inode, ip->i_no_addr, iget_test, &ip->i_no_addr);
756 	if (error == -EBUSY)
757 		goto retry;
758 	if (error)
759 		goto fail_gunlock2;
760 
761 	error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED, GL_EXACT | GL_NOPID,
762 				   &ip->i_iopen_gh);
763 	if (error)
764 		goto fail_gunlock2;
765 
766 	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, &gh);
767 	if (error)
768 		goto fail_gunlock3;
769 
770 	error = gfs2_trans_begin(sdp, blocks, 0);
771 	if (error)
772 		goto fail_gunlock3;
773 
774 	if (blocks > 1)
775 		gfs2_init_xattr(ip);
776 	init_dinode(dip, ip, symname);
777 	gfs2_trans_end(sdp);
778 
779 	glock_set_object(ip->i_gl, ip);
780 	glock_set_object(io_gl, ip);
781 	gfs2_set_iop(inode);
782 
783 	if (default_acl) {
784 		error = __gfs2_set_acl(inode, default_acl, ACL_TYPE_DEFAULT);
785 		if (error)
786 			goto fail_gunlock4;
787 		posix_acl_release(default_acl);
788 		default_acl = NULL;
789 	}
790 	if (acl) {
791 		error = __gfs2_set_acl(inode, acl, ACL_TYPE_ACCESS);
792 		if (error)
793 			goto fail_gunlock4;
794 		posix_acl_release(acl);
795 		acl = NULL;
796 	}
797 
798 	error = security_inode_init_security(&ip->i_inode, &dip->i_inode, name,
799 					     &gfs2_initxattrs, NULL);
800 	if (error)
801 		goto fail_gunlock4;
802 
803 	error = link_dinode(dip, name, ip, &da);
804 	if (error)
805 		goto fail_gunlock4;
806 
807 	mark_inode_dirty(inode);
808 	d_instantiate(dentry, inode);
809 	/* After instantiate, errors should result in evict which will destroy
810 	 * both inode and iopen glocks properly. */
811 	if (file) {
812 		file->f_mode |= FMODE_CREATED;
813 		error = finish_open(file, dentry, gfs2_open_common);
814 	}
815 	gfs2_glock_dq_uninit(&d_gh);
816 	gfs2_qa_put(ip);
817 	gfs2_glock_dq_uninit(&gh);
818 	gfs2_glock_put(io_gl);
819 	gfs2_qa_put(dip);
820 	unlock_new_inode(inode);
821 	return error;
822 
823 fail_gunlock4:
824 	glock_clear_object(ip->i_gl, ip);
825 	glock_clear_object(io_gl, ip);
826 fail_gunlock3:
827 	gfs2_glock_dq_uninit(&ip->i_iopen_gh);
828 fail_gunlock2:
829 	gfs2_glock_put(io_gl);
830 fail_free_inode:
831 	if (ip->i_gl) {
832 		gfs2_glock_put(ip->i_gl);
833 		ip->i_gl = NULL;
834 	}
835 	gfs2_rs_deltree(&ip->i_res);
836 	gfs2_qa_put(ip);
837 fail_free_acls:
838 	posix_acl_release(default_acl);
839 	posix_acl_release(acl);
840 fail_gunlock:
841 	gfs2_dir_no_add(&da);
842 	gfs2_glock_dq_uninit(&d_gh);
843 	if (!IS_ERR_OR_NULL(inode)) {
844 		set_bit(GIF_ALLOC_FAILED, &ip->i_flags);
845 		clear_nlink(inode);
846 		if (ip->i_no_addr)
847 			mark_inode_dirty(inode);
848 		if (inode->i_state & I_NEW)
849 			iget_failed(inode);
850 		else
851 			iput(inode);
852 	}
853 	if (gfs2_holder_initialized(&gh))
854 		gfs2_glock_dq_uninit(&gh);
855 fail:
856 	gfs2_qa_put(dip);
857 	return error;
858 }
859 
860 /**
861  * gfs2_create - Create a file
862  * @idmap: idmap of the mount the inode was found from
863  * @dir: The directory in which to create the file
864  * @dentry: The dentry of the new file
865  * @mode: The mode of the new file
866  * @excl: Force fail if inode exists
867  *
868  * Returns: errno
869  */
870 
871 static int gfs2_create(struct mnt_idmap *idmap, struct inode *dir,
872 		       struct dentry *dentry, umode_t mode, bool excl)
873 {
874 	return gfs2_create_inode(dir, dentry, NULL, S_IFREG | mode, 0, NULL, 0, excl);
875 }
876 
877 /**
878  * __gfs2_lookup - Look up a filename in a directory and return its inode
879  * @dir: The directory inode
880  * @dentry: The dentry of the new inode
881  * @file: File to be opened
882  *
883  *
884  * Returns: errno
885  */
886 
887 static struct dentry *__gfs2_lookup(struct inode *dir, struct dentry *dentry,
888 				    struct file *file)
889 {
890 	struct inode *inode;
891 	struct dentry *d;
892 	struct gfs2_holder gh;
893 	struct gfs2_glock *gl;
894 	int error;
895 
896 	inode = gfs2_lookupi(dir, &dentry->d_name, 0);
897 	if (inode == NULL) {
898 		d_add(dentry, NULL);
899 		return NULL;
900 	}
901 	if (IS_ERR(inode))
902 		return ERR_CAST(inode);
903 
904 	gl = GFS2_I(inode)->i_gl;
905 	error = gfs2_glock_nq_init(gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
906 	if (error) {
907 		iput(inode);
908 		return ERR_PTR(error);
909 	}
910 
911 	d = d_splice_alias(inode, dentry);
912 	if (IS_ERR(d)) {
913 		gfs2_glock_dq_uninit(&gh);
914 		return d;
915 	}
916 	if (file && S_ISREG(inode->i_mode))
917 		error = finish_open(file, dentry, gfs2_open_common);
918 
919 	gfs2_glock_dq_uninit(&gh);
920 	if (error) {
921 		dput(d);
922 		return ERR_PTR(error);
923 	}
924 	return d;
925 }
926 
927 static struct dentry *gfs2_lookup(struct inode *dir, struct dentry *dentry,
928 				  unsigned flags)
929 {
930 	return __gfs2_lookup(dir, dentry, NULL);
931 }
932 
933 /**
934  * gfs2_link - Link to a file
935  * @old_dentry: The inode to link
936  * @dir: Add link to this directory
937  * @dentry: The name of the link
938  *
939  * Link the inode in "old_dentry" into the directory "dir" with the
940  * name in "dentry".
941  *
942  * Returns: errno
943  */
944 
945 static int gfs2_link(struct dentry *old_dentry, struct inode *dir,
946 		     struct dentry *dentry)
947 {
948 	struct gfs2_inode *dip = GFS2_I(dir);
949 	struct gfs2_sbd *sdp = GFS2_SB(dir);
950 	struct inode *inode = d_inode(old_dentry);
951 	struct gfs2_inode *ip = GFS2_I(inode);
952 	struct gfs2_holder d_gh, gh;
953 	struct buffer_head *dibh;
954 	struct gfs2_diradd da = { .bh = NULL, .save_loc = 1, };
955 	int error;
956 
957 	if (S_ISDIR(inode->i_mode))
958 		return -EPERM;
959 
960 	error = gfs2_qa_get(dip);
961 	if (error)
962 		return error;
963 
964 	gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, &d_gh);
965 	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
966 
967 	error = gfs2_glock_nq(&d_gh);
968 	if (error)
969 		goto out_parent;
970 
971 	error = gfs2_glock_nq(&gh);
972 	if (error)
973 		goto out_child;
974 
975 	error = -ENOENT;
976 	if (inode->i_nlink == 0)
977 		goto out_gunlock;
978 
979 	error = gfs2_permission(&nop_mnt_idmap, dir, MAY_WRITE | MAY_EXEC);
980 	if (error)
981 		goto out_gunlock;
982 
983 	error = gfs2_dir_check(dir, &dentry->d_name, NULL);
984 	switch (error) {
985 	case -ENOENT:
986 		break;
987 	case 0:
988 		error = -EEXIST;
989 		goto out_gunlock;
990 	default:
991 		goto out_gunlock;
992 	}
993 
994 	error = -EINVAL;
995 	if (!dip->i_inode.i_nlink)
996 		goto out_gunlock;
997 	error = -EFBIG;
998 	if (dip->i_entries == (u32)-1)
999 		goto out_gunlock;
1000 	error = -EPERM;
1001 	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
1002 		goto out_gunlock;
1003 	error = -EMLINK;
1004 	if (ip->i_inode.i_nlink == (u32)-1)
1005 		goto out_gunlock;
1006 
1007 	error = gfs2_diradd_alloc_required(dir, &dentry->d_name, &da);
1008 	if (error < 0)
1009 		goto out_gunlock;
1010 
1011 	if (da.nr_blocks) {
1012 		struct gfs2_alloc_parms ap = { .target = da.nr_blocks, };
1013 		error = gfs2_quota_lock_check(dip, &ap);
1014 		if (error)
1015 			goto out_gunlock;
1016 
1017 		error = gfs2_inplace_reserve(dip, &ap);
1018 		if (error)
1019 			goto out_gunlock_q;
1020 
1021 		error = gfs2_trans_begin(sdp, gfs2_trans_da_blks(dip, &da, 2), 0);
1022 		if (error)
1023 			goto out_ipres;
1024 	} else {
1025 		error = gfs2_trans_begin(sdp, 2 * RES_DINODE + RES_LEAF, 0);
1026 		if (error)
1027 			goto out_ipres;
1028 	}
1029 
1030 	error = gfs2_meta_inode_buffer(ip, &dibh);
1031 	if (error)
1032 		goto out_end_trans;
1033 
1034 	error = gfs2_dir_add(dir, &dentry->d_name, ip, &da);
1035 	if (error)
1036 		goto out_brelse;
1037 
1038 	gfs2_trans_add_meta(ip->i_gl, dibh);
1039 	inc_nlink(&ip->i_inode);
1040 	inode_set_ctime_current(&ip->i_inode);
1041 	ihold(inode);
1042 	d_instantiate(dentry, inode);
1043 	mark_inode_dirty(inode);
1044 
1045 out_brelse:
1046 	brelse(dibh);
1047 out_end_trans:
1048 	gfs2_trans_end(sdp);
1049 out_ipres:
1050 	if (da.nr_blocks)
1051 		gfs2_inplace_release(dip);
1052 out_gunlock_q:
1053 	if (da.nr_blocks)
1054 		gfs2_quota_unlock(dip);
1055 out_gunlock:
1056 	gfs2_dir_no_add(&da);
1057 	gfs2_glock_dq(&gh);
1058 out_child:
1059 	gfs2_glock_dq(&d_gh);
1060 out_parent:
1061 	gfs2_qa_put(dip);
1062 	gfs2_holder_uninit(&d_gh);
1063 	gfs2_holder_uninit(&gh);
1064 	return error;
1065 }
1066 
1067 /*
1068  * gfs2_unlink_ok - check to see that a inode is still in a directory
1069  * @dip: the directory
1070  * @name: the name of the file
1071  * @ip: the inode
1072  *
1073  * Assumes that the lock on (at least) @dip is held.
1074  *
1075  * Returns: 0 if the parent/child relationship is correct, errno if it isn't
1076  */
1077 
1078 static int gfs2_unlink_ok(struct gfs2_inode *dip, const struct qstr *name,
1079 			  const struct gfs2_inode *ip)
1080 {
1081 	int error;
1082 
1083 	if (IS_IMMUTABLE(&ip->i_inode) || IS_APPEND(&ip->i_inode))
1084 		return -EPERM;
1085 
1086 	if ((dip->i_inode.i_mode & S_ISVTX) &&
1087 	    !uid_eq(dip->i_inode.i_uid, current_fsuid()) &&
1088 	    !uid_eq(ip->i_inode.i_uid, current_fsuid()) && !capable(CAP_FOWNER))
1089 		return -EPERM;
1090 
1091 	if (IS_APPEND(&dip->i_inode))
1092 		return -EPERM;
1093 
1094 	error = gfs2_permission(&nop_mnt_idmap, &dip->i_inode,
1095 				MAY_WRITE | MAY_EXEC);
1096 	if (error)
1097 		return error;
1098 
1099 	return gfs2_dir_check(&dip->i_inode, name, ip);
1100 }
1101 
1102 /**
1103  * gfs2_unlink_inode - Removes an inode from its parent dir and unlinks it
1104  * @dip: The parent directory
1105  * @dentry: The dentry to unlink
1106  *
1107  * Called with all the locks and in a transaction. This will only be
1108  * called for a directory after it has been checked to ensure it is empty.
1109  *
1110  * Returns: 0 on success, or an error
1111  */
1112 
1113 static int gfs2_unlink_inode(struct gfs2_inode *dip,
1114 			     const struct dentry *dentry)
1115 {
1116 	struct inode *inode = d_inode(dentry);
1117 	struct gfs2_inode *ip = GFS2_I(inode);
1118 	int error;
1119 
1120 	error = gfs2_dir_del(dip, dentry);
1121 	if (error)
1122 		return error;
1123 
1124 	ip->i_entries = 0;
1125 	inode_set_ctime_current(inode);
1126 	if (S_ISDIR(inode->i_mode))
1127 		clear_nlink(inode);
1128 	else
1129 		drop_nlink(inode);
1130 	mark_inode_dirty(inode);
1131 	if (inode->i_nlink == 0)
1132 		gfs2_unlink_di(inode);
1133 	return 0;
1134 }
1135 
1136 
1137 /**
1138  * gfs2_unlink - Unlink an inode (this does rmdir as well)
1139  * @dir: The inode of the directory containing the inode to unlink
1140  * @dentry: The file itself
1141  *
1142  * This routine uses the type of the inode as a flag to figure out
1143  * whether this is an unlink or an rmdir.
1144  *
1145  * Returns: errno
1146  */
1147 
1148 static int gfs2_unlink(struct inode *dir, struct dentry *dentry)
1149 {
1150 	struct gfs2_inode *dip = GFS2_I(dir);
1151 	struct gfs2_sbd *sdp = GFS2_SB(dir);
1152 	struct inode *inode = d_inode(dentry);
1153 	struct gfs2_inode *ip = GFS2_I(inode);
1154 	struct gfs2_holder d_gh, r_gh, gh;
1155 	struct gfs2_rgrpd *rgd;
1156 	int error;
1157 
1158 	error = gfs2_rindex_update(sdp);
1159 	if (error)
1160 		return error;
1161 
1162 	error = -EROFS;
1163 
1164 	gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, &d_gh);
1165 	gfs2_holder_init(ip->i_gl,  LM_ST_EXCLUSIVE, 0, &gh);
1166 
1167 	rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr, 1);
1168 	if (!rgd)
1169 		goto out_inodes;
1170 
1171 	gfs2_holder_init(rgd->rd_gl, LM_ST_EXCLUSIVE, LM_FLAG_NODE_SCOPE, &r_gh);
1172 
1173 
1174 	error = gfs2_glock_nq(&d_gh);
1175 	if (error)
1176 		goto out_parent;
1177 
1178 	error = gfs2_glock_nq(&gh);
1179 	if (error)
1180 		goto out_child;
1181 
1182 	error = -ENOENT;
1183 	if (inode->i_nlink == 0)
1184 		goto out_rgrp;
1185 
1186 	if (S_ISDIR(inode->i_mode)) {
1187 		error = -ENOTEMPTY;
1188 		if (ip->i_entries > 2 || inode->i_nlink > 2)
1189 			goto out_rgrp;
1190 	}
1191 
1192 	error = gfs2_glock_nq(&r_gh); /* rgrp */
1193 	if (error)
1194 		goto out_rgrp;
1195 
1196 	error = gfs2_unlink_ok(dip, &dentry->d_name, ip);
1197 	if (error)
1198 		goto out_gunlock;
1199 
1200 	error = gfs2_trans_begin(sdp, 2*RES_DINODE + 3*RES_LEAF + RES_RG_BIT, 0);
1201 	if (error)
1202 		goto out_gunlock;
1203 
1204 	error = gfs2_unlink_inode(dip, dentry);
1205 	gfs2_trans_end(sdp);
1206 
1207 out_gunlock:
1208 	gfs2_glock_dq(&r_gh);
1209 out_rgrp:
1210 	gfs2_glock_dq(&gh);
1211 out_child:
1212 	gfs2_glock_dq(&d_gh);
1213 out_parent:
1214 	gfs2_holder_uninit(&r_gh);
1215 out_inodes:
1216 	gfs2_holder_uninit(&gh);
1217 	gfs2_holder_uninit(&d_gh);
1218 	return error;
1219 }
1220 
1221 /**
1222  * gfs2_symlink - Create a symlink
1223  * @idmap: idmap of the mount the inode was found from
1224  * @dir: The directory to create the symlink in
1225  * @dentry: The dentry to put the symlink in
1226  * @symname: The thing which the link points to
1227  *
1228  * Returns: errno
1229  */
1230 
1231 static int gfs2_symlink(struct mnt_idmap *idmap, struct inode *dir,
1232 			struct dentry *dentry, const char *symname)
1233 {
1234 	unsigned int size;
1235 
1236 	size = strlen(symname);
1237 	if (size >= gfs2_max_stuffed_size(GFS2_I(dir)))
1238 		return -ENAMETOOLONG;
1239 
1240 	return gfs2_create_inode(dir, dentry, NULL, S_IFLNK | S_IRWXUGO, 0, symname, size, 0);
1241 }
1242 
1243 /**
1244  * gfs2_mkdir - Make a directory
1245  * @idmap: idmap of the mount the inode was found from
1246  * @dir: The parent directory of the new one
1247  * @dentry: The dentry of the new directory
1248  * @mode: The mode of the new directory
1249  *
1250  * Returns: errno
1251  */
1252 
1253 static int gfs2_mkdir(struct mnt_idmap *idmap, struct inode *dir,
1254 		      struct dentry *dentry, umode_t mode)
1255 {
1256 	unsigned dsize = gfs2_max_stuffed_size(GFS2_I(dir));
1257 	return gfs2_create_inode(dir, dentry, NULL, S_IFDIR | mode, 0, NULL, dsize, 0);
1258 }
1259 
1260 /**
1261  * gfs2_mknod - Make a special file
1262  * @idmap: idmap of the mount the inode was found from
1263  * @dir: The directory in which the special file will reside
1264  * @dentry: The dentry of the special file
1265  * @mode: The mode of the special file
1266  * @dev: The device specification of the special file
1267  *
1268  */
1269 
1270 static int gfs2_mknod(struct mnt_idmap *idmap, struct inode *dir,
1271 		      struct dentry *dentry, umode_t mode, dev_t dev)
1272 {
1273 	return gfs2_create_inode(dir, dentry, NULL, mode, dev, NULL, 0, 0);
1274 }
1275 
1276 /**
1277  * gfs2_atomic_open - Atomically open a file
1278  * @dir: The directory
1279  * @dentry: The proposed new entry
1280  * @file: The proposed new struct file
1281  * @flags: open flags
1282  * @mode: File mode
1283  *
1284  * Returns: error code or 0 for success
1285  */
1286 
1287 static int gfs2_atomic_open(struct inode *dir, struct dentry *dentry,
1288 			    struct file *file, unsigned flags,
1289 			    umode_t mode)
1290 {
1291 	struct dentry *d;
1292 	bool excl = !!(flags & O_EXCL);
1293 
1294 	if (!d_in_lookup(dentry))
1295 		goto skip_lookup;
1296 
1297 	d = __gfs2_lookup(dir, dentry, file);
1298 	if (IS_ERR(d))
1299 		return PTR_ERR(d);
1300 	if (d != NULL)
1301 		dentry = d;
1302 	if (d_really_is_positive(dentry)) {
1303 		if (!(file->f_mode & FMODE_OPENED))
1304 			return finish_no_open(file, d);
1305 		dput(d);
1306 		return excl && (flags & O_CREAT) ? -EEXIST : 0;
1307 	}
1308 
1309 	BUG_ON(d != NULL);
1310 
1311 skip_lookup:
1312 	if (!(flags & O_CREAT))
1313 		return -ENOENT;
1314 
1315 	return gfs2_create_inode(dir, dentry, file, S_IFREG | mode, 0, NULL, 0, excl);
1316 }
1317 
1318 /*
1319  * gfs2_ok_to_move - check if it's ok to move a directory to another directory
1320  * @this: move this
1321  * @to: to here
1322  *
1323  * Follow @to back to the root and make sure we don't encounter @this
1324  * Assumes we already hold the rename lock.
1325  *
1326  * Returns: errno
1327  */
1328 
1329 static int gfs2_ok_to_move(struct gfs2_inode *this, struct gfs2_inode *to)
1330 {
1331 	struct inode *dir = &to->i_inode;
1332 	struct super_block *sb = dir->i_sb;
1333 	struct inode *tmp;
1334 	int error = 0;
1335 
1336 	igrab(dir);
1337 
1338 	for (;;) {
1339 		if (dir == &this->i_inode) {
1340 			error = -EINVAL;
1341 			break;
1342 		}
1343 		if (dir == d_inode(sb->s_root)) {
1344 			error = 0;
1345 			break;
1346 		}
1347 
1348 		tmp = gfs2_lookupi(dir, &gfs2_qdotdot, 1);
1349 		if (!tmp) {
1350 			error = -ENOENT;
1351 			break;
1352 		}
1353 		if (IS_ERR(tmp)) {
1354 			error = PTR_ERR(tmp);
1355 			break;
1356 		}
1357 
1358 		iput(dir);
1359 		dir = tmp;
1360 	}
1361 
1362 	iput(dir);
1363 
1364 	return error;
1365 }
1366 
1367 /**
1368  * update_moved_ino - Update an inode that's being moved
1369  * @ip: The inode being moved
1370  * @ndip: The parent directory of the new filename
1371  * @dir_rename: True of ip is a directory
1372  *
1373  * Returns: errno
1374  */
1375 
1376 static int update_moved_ino(struct gfs2_inode *ip, struct gfs2_inode *ndip,
1377 			    int dir_rename)
1378 {
1379 	if (dir_rename)
1380 		return gfs2_dir_mvino(ip, &gfs2_qdotdot, ndip, DT_DIR);
1381 
1382 	inode_set_ctime_current(&ip->i_inode);
1383 	mark_inode_dirty_sync(&ip->i_inode);
1384 	return 0;
1385 }
1386 
1387 
1388 /**
1389  * gfs2_rename - Rename a file
1390  * @odir: Parent directory of old file name
1391  * @odentry: The old dentry of the file
1392  * @ndir: Parent directory of new file name
1393  * @ndentry: The new dentry of the file
1394  *
1395  * Returns: errno
1396  */
1397 
1398 static int gfs2_rename(struct inode *odir, struct dentry *odentry,
1399 		       struct inode *ndir, struct dentry *ndentry)
1400 {
1401 	struct gfs2_inode *odip = GFS2_I(odir);
1402 	struct gfs2_inode *ndip = GFS2_I(ndir);
1403 	struct gfs2_inode *ip = GFS2_I(d_inode(odentry));
1404 	struct gfs2_inode *nip = NULL;
1405 	struct gfs2_sbd *sdp = GFS2_SB(odir);
1406 	struct gfs2_holder ghs[4], r_gh, rd_gh;
1407 	struct gfs2_rgrpd *nrgd;
1408 	unsigned int num_gh;
1409 	int dir_rename = 0;
1410 	struct gfs2_diradd da = { .nr_blocks = 0, .save_loc = 0, };
1411 	unsigned int x;
1412 	int error;
1413 
1414 	gfs2_holder_mark_uninitialized(&r_gh);
1415 	gfs2_holder_mark_uninitialized(&rd_gh);
1416 	if (d_really_is_positive(ndentry)) {
1417 		nip = GFS2_I(d_inode(ndentry));
1418 		if (ip == nip)
1419 			return 0;
1420 	}
1421 
1422 	error = gfs2_rindex_update(sdp);
1423 	if (error)
1424 		return error;
1425 
1426 	error = gfs2_qa_get(ndip);
1427 	if (error)
1428 		return error;
1429 
1430 	if (odip != ndip) {
1431 		error = gfs2_glock_nq_init(sdp->sd_rename_gl, LM_ST_EXCLUSIVE,
1432 					   0, &r_gh);
1433 		if (error)
1434 			goto out;
1435 
1436 		if (S_ISDIR(ip->i_inode.i_mode)) {
1437 			dir_rename = 1;
1438 			/* don't move a directory into its subdir */
1439 			error = gfs2_ok_to_move(ip, ndip);
1440 			if (error)
1441 				goto out_gunlock_r;
1442 		}
1443 	}
1444 
1445 	num_gh = 1;
1446 	gfs2_holder_init(odip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC, ghs);
1447 	if (odip != ndip) {
1448 		gfs2_holder_init(ndip->i_gl, LM_ST_EXCLUSIVE,GL_ASYNC,
1449 				 ghs + num_gh);
1450 		num_gh++;
1451 	}
1452 	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC, ghs + num_gh);
1453 	num_gh++;
1454 
1455 	if (nip) {
1456 		gfs2_holder_init(nip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC,
1457 				 ghs + num_gh);
1458 		num_gh++;
1459 	}
1460 
1461 	for (x = 0; x < num_gh; x++) {
1462 		error = gfs2_glock_nq(ghs + x);
1463 		if (error)
1464 			goto out_gunlock;
1465 	}
1466 	error = gfs2_glock_async_wait(num_gh, ghs);
1467 	if (error)
1468 		goto out_gunlock;
1469 
1470 	if (nip) {
1471 		/* Grab the resource group glock for unlink flag twiddling.
1472 		 * This is the case where the target dinode already exists
1473 		 * so we unlink before doing the rename.
1474 		 */
1475 		nrgd = gfs2_blk2rgrpd(sdp, nip->i_no_addr, 1);
1476 		if (!nrgd) {
1477 			error = -ENOENT;
1478 			goto out_gunlock;
1479 		}
1480 		error = gfs2_glock_nq_init(nrgd->rd_gl, LM_ST_EXCLUSIVE,
1481 					   LM_FLAG_NODE_SCOPE, &rd_gh);
1482 		if (error)
1483 			goto out_gunlock;
1484 	}
1485 
1486 	error = -ENOENT;
1487 	if (ip->i_inode.i_nlink == 0)
1488 		goto out_gunlock;
1489 
1490 	/* Check out the old directory */
1491 
1492 	error = gfs2_unlink_ok(odip, &odentry->d_name, ip);
1493 	if (error)
1494 		goto out_gunlock;
1495 
1496 	/* Check out the new directory */
1497 
1498 	if (nip) {
1499 		error = gfs2_unlink_ok(ndip, &ndentry->d_name, nip);
1500 		if (error)
1501 			goto out_gunlock;
1502 
1503 		if (nip->i_inode.i_nlink == 0) {
1504 			error = -EAGAIN;
1505 			goto out_gunlock;
1506 		}
1507 
1508 		if (S_ISDIR(nip->i_inode.i_mode)) {
1509 			if (nip->i_entries < 2) {
1510 				gfs2_consist_inode(nip);
1511 				error = -EIO;
1512 				goto out_gunlock;
1513 			}
1514 			if (nip->i_entries > 2) {
1515 				error = -ENOTEMPTY;
1516 				goto out_gunlock;
1517 			}
1518 		}
1519 	} else {
1520 		error = gfs2_permission(&nop_mnt_idmap, ndir,
1521 					MAY_WRITE | MAY_EXEC);
1522 		if (error)
1523 			goto out_gunlock;
1524 
1525 		error = gfs2_dir_check(ndir, &ndentry->d_name, NULL);
1526 		switch (error) {
1527 		case -ENOENT:
1528 			error = 0;
1529 			break;
1530 		case 0:
1531 			error = -EEXIST;
1532 			goto out_gunlock;
1533 		default:
1534 			goto out_gunlock;
1535 		}
1536 
1537 		if (odip != ndip) {
1538 			if (!ndip->i_inode.i_nlink) {
1539 				error = -ENOENT;
1540 				goto out_gunlock;
1541 			}
1542 			if (ndip->i_entries == (u32)-1) {
1543 				error = -EFBIG;
1544 				goto out_gunlock;
1545 			}
1546 			if (S_ISDIR(ip->i_inode.i_mode) &&
1547 			    ndip->i_inode.i_nlink == (u32)-1) {
1548 				error = -EMLINK;
1549 				goto out_gunlock;
1550 			}
1551 		}
1552 	}
1553 
1554 	/* Check out the dir to be renamed */
1555 
1556 	if (dir_rename) {
1557 		error = gfs2_permission(&nop_mnt_idmap, d_inode(odentry),
1558 					MAY_WRITE);
1559 		if (error)
1560 			goto out_gunlock;
1561 	}
1562 
1563 	if (nip == NULL) {
1564 		error = gfs2_diradd_alloc_required(ndir, &ndentry->d_name, &da);
1565 		if (error)
1566 			goto out_gunlock;
1567 	}
1568 
1569 	if (da.nr_blocks) {
1570 		struct gfs2_alloc_parms ap = { .target = da.nr_blocks, };
1571 		error = gfs2_quota_lock_check(ndip, &ap);
1572 		if (error)
1573 			goto out_gunlock;
1574 
1575 		error = gfs2_inplace_reserve(ndip, &ap);
1576 		if (error)
1577 			goto out_gunlock_q;
1578 
1579 		error = gfs2_trans_begin(sdp, gfs2_trans_da_blks(ndip, &da, 4) +
1580 					 4 * RES_LEAF + 4, 0);
1581 		if (error)
1582 			goto out_ipreserv;
1583 	} else {
1584 		error = gfs2_trans_begin(sdp, 4 * RES_DINODE +
1585 					 5 * RES_LEAF + 4, 0);
1586 		if (error)
1587 			goto out_gunlock;
1588 	}
1589 
1590 	/* Remove the target file, if it exists */
1591 
1592 	if (nip)
1593 		error = gfs2_unlink_inode(ndip, ndentry);
1594 
1595 	error = update_moved_ino(ip, ndip, dir_rename);
1596 	if (error)
1597 		goto out_end_trans;
1598 
1599 	error = gfs2_dir_del(odip, odentry);
1600 	if (error)
1601 		goto out_end_trans;
1602 
1603 	error = gfs2_dir_add(ndir, &ndentry->d_name, ip, &da);
1604 	if (error)
1605 		goto out_end_trans;
1606 
1607 out_end_trans:
1608 	gfs2_trans_end(sdp);
1609 out_ipreserv:
1610 	if (da.nr_blocks)
1611 		gfs2_inplace_release(ndip);
1612 out_gunlock_q:
1613 	if (da.nr_blocks)
1614 		gfs2_quota_unlock(ndip);
1615 out_gunlock:
1616 	gfs2_dir_no_add(&da);
1617 	if (gfs2_holder_initialized(&rd_gh))
1618 		gfs2_glock_dq_uninit(&rd_gh);
1619 
1620 	while (x--) {
1621 		if (gfs2_holder_queued(ghs + x))
1622 			gfs2_glock_dq(ghs + x);
1623 		gfs2_holder_uninit(ghs + x);
1624 	}
1625 out_gunlock_r:
1626 	if (gfs2_holder_initialized(&r_gh))
1627 		gfs2_glock_dq_uninit(&r_gh);
1628 out:
1629 	gfs2_qa_put(ndip);
1630 	return error;
1631 }
1632 
1633 /**
1634  * gfs2_exchange - exchange two files
1635  * @odir: Parent directory of old file name
1636  * @odentry: The old dentry of the file
1637  * @ndir: Parent directory of new file name
1638  * @ndentry: The new dentry of the file
1639  * @flags: The rename flags
1640  *
1641  * Returns: errno
1642  */
1643 
1644 static int gfs2_exchange(struct inode *odir, struct dentry *odentry,
1645 			 struct inode *ndir, struct dentry *ndentry,
1646 			 unsigned int flags)
1647 {
1648 	struct gfs2_inode *odip = GFS2_I(odir);
1649 	struct gfs2_inode *ndip = GFS2_I(ndir);
1650 	struct gfs2_inode *oip = GFS2_I(odentry->d_inode);
1651 	struct gfs2_inode *nip = GFS2_I(ndentry->d_inode);
1652 	struct gfs2_sbd *sdp = GFS2_SB(odir);
1653 	struct gfs2_holder ghs[4], r_gh;
1654 	unsigned int num_gh;
1655 	unsigned int x;
1656 	umode_t old_mode = oip->i_inode.i_mode;
1657 	umode_t new_mode = nip->i_inode.i_mode;
1658 	int error;
1659 
1660 	gfs2_holder_mark_uninitialized(&r_gh);
1661 	error = gfs2_rindex_update(sdp);
1662 	if (error)
1663 		return error;
1664 
1665 	if (odip != ndip) {
1666 		error = gfs2_glock_nq_init(sdp->sd_rename_gl, LM_ST_EXCLUSIVE,
1667 					   0, &r_gh);
1668 		if (error)
1669 			goto out;
1670 
1671 		if (S_ISDIR(old_mode)) {
1672 			/* don't move a directory into its subdir */
1673 			error = gfs2_ok_to_move(oip, ndip);
1674 			if (error)
1675 				goto out_gunlock_r;
1676 		}
1677 
1678 		if (S_ISDIR(new_mode)) {
1679 			/* don't move a directory into its subdir */
1680 			error = gfs2_ok_to_move(nip, odip);
1681 			if (error)
1682 				goto out_gunlock_r;
1683 		}
1684 	}
1685 
1686 	num_gh = 1;
1687 	gfs2_holder_init(odip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC, ghs);
1688 	if (odip != ndip) {
1689 		gfs2_holder_init(ndip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC,
1690 				 ghs + num_gh);
1691 		num_gh++;
1692 	}
1693 	gfs2_holder_init(oip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC, ghs + num_gh);
1694 	num_gh++;
1695 
1696 	gfs2_holder_init(nip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC, ghs + num_gh);
1697 	num_gh++;
1698 
1699 	for (x = 0; x < num_gh; x++) {
1700 		error = gfs2_glock_nq(ghs + x);
1701 		if (error)
1702 			goto out_gunlock;
1703 	}
1704 
1705 	error = gfs2_glock_async_wait(num_gh, ghs);
1706 	if (error)
1707 		goto out_gunlock;
1708 
1709 	error = -ENOENT;
1710 	if (oip->i_inode.i_nlink == 0 || nip->i_inode.i_nlink == 0)
1711 		goto out_gunlock;
1712 
1713 	error = gfs2_unlink_ok(odip, &odentry->d_name, oip);
1714 	if (error)
1715 		goto out_gunlock;
1716 	error = gfs2_unlink_ok(ndip, &ndentry->d_name, nip);
1717 	if (error)
1718 		goto out_gunlock;
1719 
1720 	if (S_ISDIR(old_mode)) {
1721 		error = gfs2_permission(&nop_mnt_idmap, odentry->d_inode,
1722 					MAY_WRITE);
1723 		if (error)
1724 			goto out_gunlock;
1725 	}
1726 	if (S_ISDIR(new_mode)) {
1727 		error = gfs2_permission(&nop_mnt_idmap, ndentry->d_inode,
1728 					MAY_WRITE);
1729 		if (error)
1730 			goto out_gunlock;
1731 	}
1732 	error = gfs2_trans_begin(sdp, 4 * RES_DINODE + 4 * RES_LEAF, 0);
1733 	if (error)
1734 		goto out_gunlock;
1735 
1736 	error = update_moved_ino(oip, ndip, S_ISDIR(old_mode));
1737 	if (error)
1738 		goto out_end_trans;
1739 
1740 	error = update_moved_ino(nip, odip, S_ISDIR(new_mode));
1741 	if (error)
1742 		goto out_end_trans;
1743 
1744 	error = gfs2_dir_mvino(ndip, &ndentry->d_name, oip,
1745 			       IF2DT(old_mode));
1746 	if (error)
1747 		goto out_end_trans;
1748 
1749 	error = gfs2_dir_mvino(odip, &odentry->d_name, nip,
1750 			       IF2DT(new_mode));
1751 	if (error)
1752 		goto out_end_trans;
1753 
1754 	if (odip != ndip) {
1755 		if (S_ISDIR(new_mode) && !S_ISDIR(old_mode)) {
1756 			inc_nlink(&odip->i_inode);
1757 			drop_nlink(&ndip->i_inode);
1758 		} else if (S_ISDIR(old_mode) && !S_ISDIR(new_mode)) {
1759 			inc_nlink(&ndip->i_inode);
1760 			drop_nlink(&odip->i_inode);
1761 		}
1762 	}
1763 	mark_inode_dirty(&ndip->i_inode);
1764 	if (odip != ndip)
1765 		mark_inode_dirty(&odip->i_inode);
1766 
1767 out_end_trans:
1768 	gfs2_trans_end(sdp);
1769 out_gunlock:
1770 	while (x--) {
1771 		if (gfs2_holder_queued(ghs + x))
1772 			gfs2_glock_dq(ghs + x);
1773 		gfs2_holder_uninit(ghs + x);
1774 	}
1775 out_gunlock_r:
1776 	if (gfs2_holder_initialized(&r_gh))
1777 		gfs2_glock_dq_uninit(&r_gh);
1778 out:
1779 	return error;
1780 }
1781 
1782 static int gfs2_rename2(struct mnt_idmap *idmap, struct inode *odir,
1783 			struct dentry *odentry, struct inode *ndir,
1784 			struct dentry *ndentry, unsigned int flags)
1785 {
1786 	flags &= ~RENAME_NOREPLACE;
1787 
1788 	if (flags & ~RENAME_EXCHANGE)
1789 		return -EINVAL;
1790 
1791 	if (flags & RENAME_EXCHANGE)
1792 		return gfs2_exchange(odir, odentry, ndir, ndentry, flags);
1793 
1794 	return gfs2_rename(odir, odentry, ndir, ndentry);
1795 }
1796 
1797 /**
1798  * gfs2_get_link - Follow a symbolic link
1799  * @dentry: The dentry of the link
1800  * @inode: The inode of the link
1801  * @done: destructor for return value
1802  *
1803  * This can handle symlinks of any size.
1804  *
1805  * Returns: 0 on success or error code
1806  */
1807 
1808 static const char *gfs2_get_link(struct dentry *dentry,
1809 				 struct inode *inode,
1810 				 struct delayed_call *done)
1811 {
1812 	struct gfs2_inode *ip = GFS2_I(inode);
1813 	struct gfs2_holder i_gh;
1814 	struct buffer_head *dibh;
1815 	unsigned int size;
1816 	char *buf;
1817 	int error;
1818 
1819 	if (!dentry)
1820 		return ERR_PTR(-ECHILD);
1821 
1822 	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
1823 	error = gfs2_glock_nq(&i_gh);
1824 	if (error) {
1825 		gfs2_holder_uninit(&i_gh);
1826 		return ERR_PTR(error);
1827 	}
1828 
1829 	size = (unsigned int)i_size_read(&ip->i_inode);
1830 	if (size == 0) {
1831 		gfs2_consist_inode(ip);
1832 		buf = ERR_PTR(-EIO);
1833 		goto out;
1834 	}
1835 
1836 	error = gfs2_meta_inode_buffer(ip, &dibh);
1837 	if (error) {
1838 		buf = ERR_PTR(error);
1839 		goto out;
1840 	}
1841 
1842 	buf = kzalloc(size + 1, GFP_NOFS);
1843 	if (!buf)
1844 		buf = ERR_PTR(-ENOMEM);
1845 	else
1846 		memcpy(buf, dibh->b_data + sizeof(struct gfs2_dinode), size);
1847 	brelse(dibh);
1848 out:
1849 	gfs2_glock_dq_uninit(&i_gh);
1850 	if (!IS_ERR(buf))
1851 		set_delayed_call(done, kfree_link, buf);
1852 	return buf;
1853 }
1854 
1855 /**
1856  * gfs2_permission
1857  * @idmap: idmap of the mount the inode was found from
1858  * @inode: The inode
1859  * @mask: The mask to be tested
1860  *
1861  * This may be called from the VFS directly, or from within GFS2 with the
1862  * inode locked, so we look to see if the glock is already locked and only
1863  * lock the glock if its not already been done.
1864  *
1865  * Returns: errno
1866  */
1867 
1868 int gfs2_permission(struct mnt_idmap *idmap, struct inode *inode,
1869 		    int mask)
1870 {
1871 	int may_not_block = mask & MAY_NOT_BLOCK;
1872 	struct gfs2_inode *ip;
1873 	struct gfs2_holder i_gh;
1874 	struct gfs2_glock *gl;
1875 	int error;
1876 
1877 	gfs2_holder_mark_uninitialized(&i_gh);
1878 	ip = GFS2_I(inode);
1879 	gl = rcu_dereference_check(ip->i_gl, !may_not_block);
1880 	if (unlikely(!gl)) {
1881 		/* inode is getting torn down, must be RCU mode */
1882 		WARN_ON_ONCE(!may_not_block);
1883 		return -ECHILD;
1884         }
1885 	if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
1886 		int noblock = may_not_block ? GL_NOBLOCK : 0;
1887 		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
1888 					   LM_FLAG_ANY | noblock, &i_gh);
1889 		if (error)
1890 			return error;
1891 	}
1892 
1893 	if ((mask & MAY_WRITE) && IS_IMMUTABLE(inode))
1894 		error = -EPERM;
1895 	else
1896 		error = generic_permission(&nop_mnt_idmap, inode, mask);
1897 	if (gfs2_holder_initialized(&i_gh))
1898 		gfs2_glock_dq_uninit(&i_gh);
1899 
1900 	return error;
1901 }
1902 
1903 static int __gfs2_setattr_simple(struct inode *inode, struct iattr *attr)
1904 {
1905 	setattr_copy(&nop_mnt_idmap, inode, attr);
1906 	mark_inode_dirty(inode);
1907 	return 0;
1908 }
1909 
1910 static int gfs2_setattr_simple(struct inode *inode, struct iattr *attr)
1911 {
1912 	int error;
1913 
1914 	if (current->journal_info)
1915 		return __gfs2_setattr_simple(inode, attr);
1916 
1917 	error = gfs2_trans_begin(GFS2_SB(inode), RES_DINODE, 0);
1918 	if (error)
1919 		return error;
1920 
1921 	error = __gfs2_setattr_simple(inode, attr);
1922 	gfs2_trans_end(GFS2_SB(inode));
1923 	return error;
1924 }
1925 
1926 static int setattr_chown(struct inode *inode, struct iattr *attr)
1927 {
1928 	struct gfs2_inode *ip = GFS2_I(inode);
1929 	struct gfs2_sbd *sdp = GFS2_SB(inode);
1930 	kuid_t ouid, nuid;
1931 	kgid_t ogid, ngid;
1932 	int error;
1933 	struct gfs2_alloc_parms ap = {};
1934 
1935 	ouid = inode->i_uid;
1936 	ogid = inode->i_gid;
1937 	nuid = attr->ia_uid;
1938 	ngid = attr->ia_gid;
1939 
1940 	if (!(attr->ia_valid & ATTR_UID) || uid_eq(ouid, nuid))
1941 		ouid = nuid = NO_UID_QUOTA_CHANGE;
1942 	if (!(attr->ia_valid & ATTR_GID) || gid_eq(ogid, ngid))
1943 		ogid = ngid = NO_GID_QUOTA_CHANGE;
1944 	error = gfs2_qa_get(ip);
1945 	if (error)
1946 		return error;
1947 
1948 	error = gfs2_rindex_update(sdp);
1949 	if (error)
1950 		goto out;
1951 
1952 	error = gfs2_quota_lock(ip, nuid, ngid);
1953 	if (error)
1954 		goto out;
1955 
1956 	ap.target = gfs2_get_inode_blocks(&ip->i_inode);
1957 
1958 	if (!uid_eq(ouid, NO_UID_QUOTA_CHANGE) ||
1959 	    !gid_eq(ogid, NO_GID_QUOTA_CHANGE)) {
1960 		error = gfs2_quota_check(ip, nuid, ngid, &ap);
1961 		if (error)
1962 			goto out_gunlock_q;
1963 	}
1964 
1965 	error = gfs2_trans_begin(sdp, RES_DINODE + 2 * RES_QUOTA, 0);
1966 	if (error)
1967 		goto out_gunlock_q;
1968 
1969 	error = gfs2_setattr_simple(inode, attr);
1970 	if (error)
1971 		goto out_end_trans;
1972 
1973 	if (!uid_eq(ouid, NO_UID_QUOTA_CHANGE) ||
1974 	    !gid_eq(ogid, NO_GID_QUOTA_CHANGE)) {
1975 		gfs2_quota_change(ip, -(s64)ap.target, ouid, ogid);
1976 		gfs2_quota_change(ip, ap.target, nuid, ngid);
1977 	}
1978 
1979 out_end_trans:
1980 	gfs2_trans_end(sdp);
1981 out_gunlock_q:
1982 	gfs2_quota_unlock(ip);
1983 out:
1984 	gfs2_qa_put(ip);
1985 	return error;
1986 }
1987 
1988 /**
1989  * gfs2_setattr - Change attributes on an inode
1990  * @idmap: idmap of the mount the inode was found from
1991  * @dentry: The dentry which is changing
1992  * @attr: The structure describing the change
1993  *
1994  * The VFS layer wants to change one or more of an inodes attributes.  Write
1995  * that change out to disk.
1996  *
1997  * Returns: errno
1998  */
1999 
2000 static int gfs2_setattr(struct mnt_idmap *idmap,
2001 			struct dentry *dentry, struct iattr *attr)
2002 {
2003 	struct inode *inode = d_inode(dentry);
2004 	struct gfs2_inode *ip = GFS2_I(inode);
2005 	struct gfs2_holder i_gh;
2006 	int error;
2007 
2008 	error = gfs2_qa_get(ip);
2009 	if (error)
2010 		return error;
2011 
2012 	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
2013 	if (error)
2014 		goto out;
2015 
2016 	error = may_setattr(&nop_mnt_idmap, inode, attr->ia_valid);
2017 	if (error)
2018 		goto error;
2019 
2020 	error = setattr_prepare(&nop_mnt_idmap, dentry, attr);
2021 	if (error)
2022 		goto error;
2023 
2024 	if (attr->ia_valid & ATTR_SIZE)
2025 		error = gfs2_setattr_size(inode, attr->ia_size);
2026 	else if (attr->ia_valid & (ATTR_UID | ATTR_GID))
2027 		error = setattr_chown(inode, attr);
2028 	else {
2029 		error = gfs2_setattr_simple(inode, attr);
2030 		if (!error && attr->ia_valid & ATTR_MODE)
2031 			error = posix_acl_chmod(&nop_mnt_idmap, dentry,
2032 						inode->i_mode);
2033 	}
2034 
2035 error:
2036 	if (!error)
2037 		mark_inode_dirty(inode);
2038 	gfs2_glock_dq_uninit(&i_gh);
2039 out:
2040 	gfs2_qa_put(ip);
2041 	return error;
2042 }
2043 
2044 /**
2045  * gfs2_getattr - Read out an inode's attributes
2046  * @idmap: idmap of the mount the inode was found from
2047  * @path: Object to query
2048  * @stat: The inode's stats
2049  * @request_mask: Mask of STATX_xxx flags indicating the caller's interests
2050  * @flags: AT_STATX_xxx setting
2051  *
2052  * This may be called from the VFS directly, or from within GFS2 with the
2053  * inode locked, so we look to see if the glock is already locked and only
2054  * lock the glock if its not already been done. Note that its the NFS
2055  * readdirplus operation which causes this to be called (from filldir)
2056  * with the glock already held.
2057  *
2058  * Returns: errno
2059  */
2060 
2061 static int gfs2_getattr(struct mnt_idmap *idmap,
2062 			const struct path *path, struct kstat *stat,
2063 			u32 request_mask, unsigned int flags)
2064 {
2065 	struct inode *inode = d_inode(path->dentry);
2066 	struct gfs2_inode *ip = GFS2_I(inode);
2067 	struct gfs2_holder gh;
2068 	u32 gfsflags;
2069 	int error;
2070 
2071 	gfs2_holder_mark_uninitialized(&gh);
2072 	if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
2073 		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
2074 		if (error)
2075 			return error;
2076 	}
2077 
2078 	gfsflags = ip->i_diskflags;
2079 	if (gfsflags & GFS2_DIF_APPENDONLY)
2080 		stat->attributes |= STATX_ATTR_APPEND;
2081 	if (gfsflags & GFS2_DIF_IMMUTABLE)
2082 		stat->attributes |= STATX_ATTR_IMMUTABLE;
2083 
2084 	stat->attributes_mask |= (STATX_ATTR_APPEND |
2085 				  STATX_ATTR_COMPRESSED |
2086 				  STATX_ATTR_ENCRYPTED |
2087 				  STATX_ATTR_IMMUTABLE |
2088 				  STATX_ATTR_NODUMP);
2089 
2090 	generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);
2091 
2092 	if (gfs2_holder_initialized(&gh))
2093 		gfs2_glock_dq_uninit(&gh);
2094 
2095 	return 0;
2096 }
2097 
2098 static int gfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2099 		       u64 start, u64 len)
2100 {
2101 	struct gfs2_inode *ip = GFS2_I(inode);
2102 	struct gfs2_holder gh;
2103 	int ret;
2104 
2105 	inode_lock_shared(inode);
2106 
2107 	ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
2108 	if (ret)
2109 		goto out;
2110 
2111 	ret = iomap_fiemap(inode, fieinfo, start, len, &gfs2_iomap_ops);
2112 
2113 	gfs2_glock_dq_uninit(&gh);
2114 
2115 out:
2116 	inode_unlock_shared(inode);
2117 	return ret;
2118 }
2119 
2120 loff_t gfs2_seek_data(struct file *file, loff_t offset)
2121 {
2122 	struct inode *inode = file->f_mapping->host;
2123 	struct gfs2_inode *ip = GFS2_I(inode);
2124 	struct gfs2_holder gh;
2125 	loff_t ret;
2126 
2127 	inode_lock_shared(inode);
2128 	ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
2129 	if (!ret)
2130 		ret = iomap_seek_data(inode, offset, &gfs2_iomap_ops);
2131 	gfs2_glock_dq_uninit(&gh);
2132 	inode_unlock_shared(inode);
2133 
2134 	if (ret < 0)
2135 		return ret;
2136 	return vfs_setpos(file, ret, inode->i_sb->s_maxbytes);
2137 }
2138 
2139 loff_t gfs2_seek_hole(struct file *file, loff_t offset)
2140 {
2141 	struct inode *inode = file->f_mapping->host;
2142 	struct gfs2_inode *ip = GFS2_I(inode);
2143 	struct gfs2_holder gh;
2144 	loff_t ret;
2145 
2146 	inode_lock_shared(inode);
2147 	ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
2148 	if (!ret)
2149 		ret = iomap_seek_hole(inode, offset, &gfs2_iomap_ops);
2150 	gfs2_glock_dq_uninit(&gh);
2151 	inode_unlock_shared(inode);
2152 
2153 	if (ret < 0)
2154 		return ret;
2155 	return vfs_setpos(file, ret, inode->i_sb->s_maxbytes);
2156 }
2157 
2158 static int gfs2_update_time(struct inode *inode, int flags)
2159 {
2160 	struct gfs2_inode *ip = GFS2_I(inode);
2161 	struct gfs2_glock *gl = ip->i_gl;
2162 	struct gfs2_holder *gh;
2163 	int error;
2164 
2165 	gh = gfs2_glock_is_locked_by_me(gl);
2166 	if (gh && gl->gl_state != LM_ST_EXCLUSIVE) {
2167 		gfs2_glock_dq(gh);
2168 		gfs2_holder_reinit(LM_ST_EXCLUSIVE, 0, gh);
2169 		error = gfs2_glock_nq(gh);
2170 		if (error)
2171 			return error;
2172 	}
2173 	generic_update_time(inode, flags);
2174 	return 0;
2175 }
2176 
2177 static const struct inode_operations gfs2_file_iops = {
2178 	.permission = gfs2_permission,
2179 	.setattr = gfs2_setattr,
2180 	.getattr = gfs2_getattr,
2181 	.listxattr = gfs2_listxattr,
2182 	.fiemap = gfs2_fiemap,
2183 	.get_inode_acl = gfs2_get_acl,
2184 	.set_acl = gfs2_set_acl,
2185 	.update_time = gfs2_update_time,
2186 	.fileattr_get = gfs2_fileattr_get,
2187 	.fileattr_set = gfs2_fileattr_set,
2188 };
2189 
2190 static const struct inode_operations gfs2_dir_iops = {
2191 	.create = gfs2_create,
2192 	.lookup = gfs2_lookup,
2193 	.link = gfs2_link,
2194 	.unlink = gfs2_unlink,
2195 	.symlink = gfs2_symlink,
2196 	.mkdir = gfs2_mkdir,
2197 	.rmdir = gfs2_unlink,
2198 	.mknod = gfs2_mknod,
2199 	.rename = gfs2_rename2,
2200 	.permission = gfs2_permission,
2201 	.setattr = gfs2_setattr,
2202 	.getattr = gfs2_getattr,
2203 	.listxattr = gfs2_listxattr,
2204 	.fiemap = gfs2_fiemap,
2205 	.get_inode_acl = gfs2_get_acl,
2206 	.set_acl = gfs2_set_acl,
2207 	.update_time = gfs2_update_time,
2208 	.atomic_open = gfs2_atomic_open,
2209 	.fileattr_get = gfs2_fileattr_get,
2210 	.fileattr_set = gfs2_fileattr_set,
2211 };
2212 
2213 static const struct inode_operations gfs2_symlink_iops = {
2214 	.get_link = gfs2_get_link,
2215 	.permission = gfs2_permission,
2216 	.setattr = gfs2_setattr,
2217 	.getattr = gfs2_getattr,
2218 	.listxattr = gfs2_listxattr,
2219 	.fiemap = gfs2_fiemap,
2220 };
2221 
2222