xref: /linux/fs/gfs2/inode.c (revision 87c9c16317882dd6dbbc07e349bc3223e14f3244)
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 static int iget_test(struct inode *inode, void *opaque)
44 {
45 	u64 no_addr = *(u64 *)opaque;
46 
47 	return GFS2_I(inode)->i_no_addr == no_addr;
48 }
49 
50 static int iget_set(struct inode *inode, void *opaque)
51 {
52 	u64 no_addr = *(u64 *)opaque;
53 
54 	GFS2_I(inode)->i_no_addr = no_addr;
55 	inode->i_ino = no_addr;
56 	return 0;
57 }
58 
59 static struct inode *gfs2_iget(struct super_block *sb, u64 no_addr)
60 {
61 	struct inode *inode;
62 
63 repeat:
64 	inode = iget5_locked(sb, no_addr, iget_test, iget_set, &no_addr);
65 	if (!inode)
66 		return inode;
67 	if (is_bad_inode(inode)) {
68 		iput(inode);
69 		goto repeat;
70 	}
71 	return inode;
72 }
73 
74 /**
75  * gfs2_set_iop - Sets inode operations
76  * @inode: The inode with correct i_mode filled in
77  *
78  * GFS2 lookup code fills in vfs inode contents based on info obtained
79  * from directory entry inside gfs2_inode_lookup().
80  */
81 
82 static void gfs2_set_iop(struct inode *inode)
83 {
84 	struct gfs2_sbd *sdp = GFS2_SB(inode);
85 	umode_t mode = inode->i_mode;
86 
87 	if (S_ISREG(mode)) {
88 		inode->i_op = &gfs2_file_iops;
89 		if (gfs2_localflocks(sdp))
90 			inode->i_fop = &gfs2_file_fops_nolock;
91 		else
92 			inode->i_fop = &gfs2_file_fops;
93 	} else if (S_ISDIR(mode)) {
94 		inode->i_op = &gfs2_dir_iops;
95 		if (gfs2_localflocks(sdp))
96 			inode->i_fop = &gfs2_dir_fops_nolock;
97 		else
98 			inode->i_fop = &gfs2_dir_fops;
99 	} else if (S_ISLNK(mode)) {
100 		inode->i_op = &gfs2_symlink_iops;
101 	} else {
102 		inode->i_op = &gfs2_file_iops;
103 		init_special_inode(inode, inode->i_mode, inode->i_rdev);
104 	}
105 }
106 
107 /**
108  * gfs2_inode_lookup - Lookup an inode
109  * @sb: The super block
110  * @type: The type of the inode
111  * @no_addr: The inode number
112  * @no_formal_ino: The inode generation number
113  * @blktype: Requested block type (GFS2_BLKST_DINODE or GFS2_BLKST_UNLINKED;
114  *           GFS2_BLKST_FREE to indicate not to verify)
115  *
116  * If @type is DT_UNKNOWN, the inode type is fetched from disk.
117  *
118  * If @blktype is anything other than GFS2_BLKST_FREE (which is used as a
119  * placeholder because it doesn't otherwise make sense), the on-disk block type
120  * is verified to be @blktype.
121  *
122  * When @no_formal_ino is non-zero, this function will return ERR_PTR(-ESTALE)
123  * if it detects that @no_formal_ino doesn't match the actual inode generation
124  * number.  However, it doesn't always know unless @type is DT_UNKNOWN.
125  *
126  * Returns: A VFS inode, or an error
127  */
128 
129 struct inode *gfs2_inode_lookup(struct super_block *sb, unsigned int type,
130 				u64 no_addr, u64 no_formal_ino,
131 				unsigned int blktype)
132 {
133 	struct inode *inode;
134 	struct gfs2_inode *ip;
135 	struct gfs2_glock *io_gl = NULL;
136 	struct gfs2_holder i_gh;
137 	int error;
138 
139 	gfs2_holder_mark_uninitialized(&i_gh);
140 	inode = gfs2_iget(sb, no_addr);
141 	if (!inode)
142 		return ERR_PTR(-ENOMEM);
143 
144 	ip = GFS2_I(inode);
145 
146 	if (inode->i_state & I_NEW) {
147 		struct gfs2_sbd *sdp = GFS2_SB(inode);
148 
149 		error = gfs2_glock_get(sdp, no_addr, &gfs2_inode_glops, CREATE, &ip->i_gl);
150 		if (unlikely(error))
151 			goto fail;
152 		flush_delayed_work(&ip->i_gl->gl_work);
153 
154 		error = gfs2_glock_get(sdp, no_addr, &gfs2_iopen_glops, CREATE, &io_gl);
155 		if (unlikely(error))
156 			goto fail;
157 		if (blktype != GFS2_BLKST_UNLINKED)
158 			gfs2_cancel_delete_work(io_gl);
159 
160 		if (type == DT_UNKNOWN || blktype != GFS2_BLKST_FREE) {
161 			/*
162 			 * The GL_SKIP flag indicates to skip reading the inode
163 			 * block.  We read the inode with gfs2_inode_refresh
164 			 * after possibly checking the block type.
165 			 */
166 			error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE,
167 						   GL_SKIP, &i_gh);
168 			if (error)
169 				goto fail;
170 
171 			error = -ESTALE;
172 			if (no_formal_ino &&
173 			    gfs2_inode_already_deleted(ip->i_gl, no_formal_ino))
174 				goto fail;
175 
176 			if (blktype != GFS2_BLKST_FREE) {
177 				error = gfs2_check_blk_type(sdp, no_addr,
178 							    blktype);
179 				if (error)
180 					goto fail;
181 			}
182 		}
183 
184 		glock_set_object(ip->i_gl, ip);
185 		set_bit(GIF_INVALID, &ip->i_flags);
186 		error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED, GL_EXACT, &ip->i_iopen_gh);
187 		if (unlikely(error))
188 			goto fail;
189 		glock_set_object(ip->i_iopen_gh.gh_gl, ip);
190 		gfs2_glock_put(io_gl);
191 		io_gl = NULL;
192 
193 		/* Lowest possible timestamp; will be overwritten in gfs2_dinode_in. */
194 		inode->i_atime.tv_sec = 1LL << (8 * sizeof(inode->i_atime.tv_sec) - 1);
195 		inode->i_atime.tv_nsec = 0;
196 
197 		if (type == DT_UNKNOWN) {
198 			/* Inode glock must be locked already */
199 			error = gfs2_inode_refresh(GFS2_I(inode));
200 			if (error)
201 				goto fail;
202 		} else {
203 			ip->i_no_formal_ino = no_formal_ino;
204 			inode->i_mode = DT2IF(type);
205 		}
206 
207 		if (gfs2_holder_initialized(&i_gh))
208 			gfs2_glock_dq_uninit(&i_gh);
209 
210 		gfs2_set_iop(inode);
211 	}
212 
213 	if (no_formal_ino && ip->i_no_formal_ino &&
214 	    no_formal_ino != ip->i_no_formal_ino) {
215 		error = -ESTALE;
216 		if (inode->i_state & I_NEW)
217 			goto fail;
218 		iput(inode);
219 		return ERR_PTR(error);
220 	}
221 
222 	if (inode->i_state & I_NEW)
223 		unlock_new_inode(inode);
224 
225 	return inode;
226 
227 fail:
228 	if (io_gl)
229 		gfs2_glock_put(io_gl);
230 	if (gfs2_holder_initialized(&i_gh))
231 		gfs2_glock_dq_uninit(&i_gh);
232 	iget_failed(inode);
233 	return ERR_PTR(error);
234 }
235 
236 /**
237  * gfs2_lookup_by_inum - look up an inode by inode number
238  * @sdp: The super block
239  * @no_addr: The inode number
240  * @no_formal_ino: The inode generation number (0 for any)
241  * @blktype: Requested block type (see gfs2_inode_lookup)
242  */
243 struct inode *gfs2_lookup_by_inum(struct gfs2_sbd *sdp, u64 no_addr,
244 				  u64 no_formal_ino, unsigned int blktype)
245 {
246 	struct super_block *sb = sdp->sd_vfs;
247 	struct inode *inode;
248 	int error;
249 
250 	inode = gfs2_inode_lookup(sb, DT_UNKNOWN, no_addr, no_formal_ino,
251 				  blktype);
252 	if (IS_ERR(inode))
253 		return inode;
254 
255 	if (no_formal_ino) {
256 		error = -EIO;
257 		if (GFS2_I(inode)->i_diskflags & GFS2_DIF_SYSTEM)
258 			goto fail_iput;
259 	}
260 	return inode;
261 
262 fail_iput:
263 	iput(inode);
264 	return ERR_PTR(error);
265 }
266 
267 
268 struct inode *gfs2_lookup_simple(struct inode *dip, const char *name)
269 {
270 	struct qstr qstr;
271 	struct inode *inode;
272 	gfs2_str2qstr(&qstr, name);
273 	inode = gfs2_lookupi(dip, &qstr, 1);
274 	/* gfs2_lookupi has inconsistent callers: vfs
275 	 * related routines expect NULL for no entry found,
276 	 * gfs2_lookup_simple callers expect ENOENT
277 	 * and do not check for NULL.
278 	 */
279 	if (inode == NULL)
280 		return ERR_PTR(-ENOENT);
281 	else
282 		return inode;
283 }
284 
285 
286 /**
287  * gfs2_lookupi - Look up a filename in a directory and return its inode
288  * @dir: The inode of the directory containing the inode to look-up
289  * @name: The name of the inode to look for
290  * @is_root: If 1, ignore the caller's permissions
291  *
292  * This can be called via the VFS filldir function when NFS is doing
293  * a readdirplus and the inode which its intending to stat isn't
294  * already in cache. In this case we must not take the directory glock
295  * again, since the readdir call will have already taken that lock.
296  *
297  * Returns: errno
298  */
299 
300 struct inode *gfs2_lookupi(struct inode *dir, const struct qstr *name,
301 			   int is_root)
302 {
303 	struct super_block *sb = dir->i_sb;
304 	struct gfs2_inode *dip = GFS2_I(dir);
305 	struct gfs2_holder d_gh;
306 	int error = 0;
307 	struct inode *inode = NULL;
308 
309 	gfs2_holder_mark_uninitialized(&d_gh);
310 	if (!name->len || name->len > GFS2_FNAMESIZE)
311 		return ERR_PTR(-ENAMETOOLONG);
312 
313 	if ((name->len == 1 && memcmp(name->name, ".", 1) == 0) ||
314 	    (name->len == 2 && memcmp(name->name, "..", 2) == 0 &&
315 	     dir == d_inode(sb->s_root))) {
316 		igrab(dir);
317 		return dir;
318 	}
319 
320 	if (gfs2_glock_is_locked_by_me(dip->i_gl) == NULL) {
321 		error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh);
322 		if (error)
323 			return ERR_PTR(error);
324 	}
325 
326 	if (!is_root) {
327 		error = gfs2_permission(&init_user_ns, dir, MAY_EXEC);
328 		if (error)
329 			goto out;
330 	}
331 
332 	inode = gfs2_dir_search(dir, name, false);
333 	if (IS_ERR(inode))
334 		error = PTR_ERR(inode);
335 out:
336 	if (gfs2_holder_initialized(&d_gh))
337 		gfs2_glock_dq_uninit(&d_gh);
338 	if (error == -ENOENT)
339 		return NULL;
340 	return inode ? inode : ERR_PTR(error);
341 }
342 
343 /**
344  * create_ok - OK to create a new on-disk inode here?
345  * @dip:  Directory in which dinode is to be created
346  * @name:  Name of new dinode
347  * @mode:
348  *
349  * Returns: errno
350  */
351 
352 static int create_ok(struct gfs2_inode *dip, const struct qstr *name,
353 		     umode_t mode)
354 {
355 	int error;
356 
357 	error = gfs2_permission(&init_user_ns, &dip->i_inode,
358 				MAY_WRITE | MAY_EXEC);
359 	if (error)
360 		return error;
361 
362 	/*  Don't create entries in an unlinked directory  */
363 	if (!dip->i_inode.i_nlink)
364 		return -ENOENT;
365 
366 	if (dip->i_entries == (u32)-1)
367 		return -EFBIG;
368 	if (S_ISDIR(mode) && dip->i_inode.i_nlink == (u32)-1)
369 		return -EMLINK;
370 
371 	return 0;
372 }
373 
374 static void munge_mode_uid_gid(const struct gfs2_inode *dip,
375 			       struct inode *inode)
376 {
377 	if (GFS2_SB(&dip->i_inode)->sd_args.ar_suiddir &&
378 	    (dip->i_inode.i_mode & S_ISUID) &&
379 	    !uid_eq(dip->i_inode.i_uid, GLOBAL_ROOT_UID)) {
380 		if (S_ISDIR(inode->i_mode))
381 			inode->i_mode |= S_ISUID;
382 		else if (!uid_eq(dip->i_inode.i_uid, current_fsuid()))
383 			inode->i_mode &= ~07111;
384 		inode->i_uid = dip->i_inode.i_uid;
385 	} else
386 		inode->i_uid = current_fsuid();
387 
388 	if (dip->i_inode.i_mode & S_ISGID) {
389 		if (S_ISDIR(inode->i_mode))
390 			inode->i_mode |= S_ISGID;
391 		inode->i_gid = dip->i_inode.i_gid;
392 	} else
393 		inode->i_gid = current_fsgid();
394 }
395 
396 static int alloc_dinode(struct gfs2_inode *ip, u32 flags, unsigned *dblocks)
397 {
398 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
399 	struct gfs2_alloc_parms ap = { .target = *dblocks, .aflags = flags, };
400 	int error;
401 
402 	error = gfs2_quota_lock_check(ip, &ap);
403 	if (error)
404 		goto out;
405 
406 	error = gfs2_inplace_reserve(ip, &ap);
407 	if (error)
408 		goto out_quota;
409 
410 	error = gfs2_trans_begin(sdp, (*dblocks * RES_RG_BIT) + RES_STATFS + RES_QUOTA, 0);
411 	if (error)
412 		goto out_ipreserv;
413 
414 	error = gfs2_alloc_blocks(ip, &ip->i_no_addr, dblocks, 1, &ip->i_generation);
415 	ip->i_no_formal_ino = ip->i_generation;
416 	ip->i_inode.i_ino = ip->i_no_addr;
417 	ip->i_goal = ip->i_no_addr;
418 
419 	gfs2_trans_end(sdp);
420 
421 out_ipreserv:
422 	gfs2_inplace_release(ip);
423 out_quota:
424 	gfs2_quota_unlock(ip);
425 out:
426 	return error;
427 }
428 
429 static void gfs2_init_dir(struct buffer_head *dibh,
430 			  const struct gfs2_inode *parent)
431 {
432 	struct gfs2_dinode *di = (struct gfs2_dinode *)dibh->b_data;
433 	struct gfs2_dirent *dent = (struct gfs2_dirent *)(di+1);
434 
435 	gfs2_qstr2dirent(&gfs2_qdot, GFS2_DIRENT_SIZE(gfs2_qdot.len), dent);
436 	dent->de_inum = di->di_num; /* already GFS2 endian */
437 	dent->de_type = cpu_to_be16(DT_DIR);
438 
439 	dent = (struct gfs2_dirent *)((char*)dent + GFS2_DIRENT_SIZE(1));
440 	gfs2_qstr2dirent(&gfs2_qdotdot, dibh->b_size - GFS2_DIRENT_SIZE(1) - sizeof(struct gfs2_dinode), dent);
441 	gfs2_inum_out(parent, dent);
442 	dent->de_type = cpu_to_be16(DT_DIR);
443 
444 }
445 
446 /**
447  * gfs2_init_xattr - Initialise an xattr block for a new inode
448  * @ip: The inode in question
449  *
450  * This sets up an empty xattr block for a new inode, ready to
451  * take any ACLs, LSM xattrs, etc.
452  */
453 
454 static void gfs2_init_xattr(struct gfs2_inode *ip)
455 {
456 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
457 	struct buffer_head *bh;
458 	struct gfs2_ea_header *ea;
459 
460 	bh = gfs2_meta_new(ip->i_gl, ip->i_eattr);
461 	gfs2_trans_add_meta(ip->i_gl, bh);
462 	gfs2_metatype_set(bh, GFS2_METATYPE_EA, GFS2_FORMAT_EA);
463 	gfs2_buffer_clear_tail(bh, sizeof(struct gfs2_meta_header));
464 
465 	ea = GFS2_EA_BH2FIRST(bh);
466 	ea->ea_rec_len = cpu_to_be32(sdp->sd_jbsize);
467 	ea->ea_type = GFS2_EATYPE_UNUSED;
468 	ea->ea_flags = GFS2_EAFLAG_LAST;
469 
470 	brelse(bh);
471 }
472 
473 /**
474  * init_dinode - Fill in a new dinode structure
475  * @dip: The directory this inode is being created in
476  * @ip: The inode
477  * @symname: The symlink destination (if a symlink)
478  *
479  */
480 
481 static void init_dinode(struct gfs2_inode *dip, struct gfs2_inode *ip,
482 			const char *symname)
483 {
484 	struct gfs2_dinode *di;
485 	struct buffer_head *dibh;
486 
487 	dibh = gfs2_meta_new(ip->i_gl, ip->i_no_addr);
488 	gfs2_trans_add_meta(ip->i_gl, dibh);
489 	di = (struct gfs2_dinode *)dibh->b_data;
490 	gfs2_dinode_out(ip, di);
491 
492 	di->di_major = cpu_to_be32(imajor(&ip->i_inode));
493 	di->di_minor = cpu_to_be32(iminor(&ip->i_inode));
494 	di->__pad1 = 0;
495 	di->__pad2 = 0;
496 	di->__pad3 = 0;
497 	memset(&di->__pad4, 0, sizeof(di->__pad4));
498 	memset(&di->di_reserved, 0, sizeof(di->di_reserved));
499 	gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
500 
501 	switch(ip->i_inode.i_mode & S_IFMT) {
502 	case S_IFDIR:
503 		gfs2_init_dir(dibh, dip);
504 		break;
505 	case S_IFLNK:
506 		memcpy(dibh->b_data + sizeof(struct gfs2_dinode), symname, ip->i_inode.i_size);
507 		break;
508 	}
509 
510 	set_buffer_uptodate(dibh);
511 	brelse(dibh);
512 }
513 
514 /**
515  * gfs2_trans_da_blks - Calculate number of blocks to link inode
516  * @dip: The directory we are linking into
517  * @da: The dir add information
518  * @nr_inodes: The number of inodes involved
519  *
520  * This calculate the number of blocks we need to reserve in a
521  * transaction to link @nr_inodes into a directory. In most cases
522  * @nr_inodes will be 2 (the directory plus the inode being linked in)
523  * but in case of rename, 4 may be required.
524  *
525  * Returns: Number of blocks
526  */
527 
528 static unsigned gfs2_trans_da_blks(const struct gfs2_inode *dip,
529 				   const struct gfs2_diradd *da,
530 				   unsigned nr_inodes)
531 {
532 	return da->nr_blocks + gfs2_rg_blocks(dip, da->nr_blocks) +
533 	       (nr_inodes * RES_DINODE) + RES_QUOTA + RES_STATFS;
534 }
535 
536 static int link_dinode(struct gfs2_inode *dip, const struct qstr *name,
537 		       struct gfs2_inode *ip, struct gfs2_diradd *da)
538 {
539 	struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
540 	struct gfs2_alloc_parms ap = { .target = da->nr_blocks, };
541 	int error;
542 
543 	if (da->nr_blocks) {
544 		error = gfs2_quota_lock_check(dip, &ap);
545 		if (error)
546 			goto fail_quota_locks;
547 
548 		error = gfs2_inplace_reserve(dip, &ap);
549 		if (error)
550 			goto fail_quota_locks;
551 
552 		error = gfs2_trans_begin(sdp, gfs2_trans_da_blks(dip, da, 2), 0);
553 		if (error)
554 			goto fail_ipreserv;
555 	} else {
556 		error = gfs2_trans_begin(sdp, RES_LEAF + 2 * RES_DINODE, 0);
557 		if (error)
558 			goto fail_quota_locks;
559 	}
560 
561 	error = gfs2_dir_add(&dip->i_inode, name, ip, da);
562 
563 	gfs2_trans_end(sdp);
564 fail_ipreserv:
565 	gfs2_inplace_release(dip);
566 fail_quota_locks:
567 	gfs2_quota_unlock(dip);
568 	return error;
569 }
570 
571 static int gfs2_initxattrs(struct inode *inode, const struct xattr *xattr_array,
572 		    void *fs_info)
573 {
574 	const struct xattr *xattr;
575 	int err = 0;
576 
577 	for (xattr = xattr_array; xattr->name != NULL; xattr++) {
578 		err = __gfs2_xattr_set(inode, xattr->name, xattr->value,
579 				       xattr->value_len, 0,
580 				       GFS2_EATYPE_SECURITY);
581 		if (err < 0)
582 			break;
583 	}
584 	return err;
585 }
586 
587 /**
588  * gfs2_create_inode - Create a new inode
589  * @dir: The parent directory
590  * @dentry: The new dentry
591  * @file: If non-NULL, the file which is being opened
592  * @mode: The permissions on the new inode
593  * @dev: For device nodes, this is the device number
594  * @symname: For symlinks, this is the link destination
595  * @size: The initial size of the inode (ignored for directories)
596  * @excl: Force fail if inode exists
597  *
598  * Returns: 0 on success, or error code
599  */
600 
601 static int gfs2_create_inode(struct inode *dir, struct dentry *dentry,
602 			     struct file *file,
603 			     umode_t mode, dev_t dev, const char *symname,
604 			     unsigned int size, int excl)
605 {
606 	const struct qstr *name = &dentry->d_name;
607 	struct posix_acl *default_acl, *acl;
608 	struct gfs2_holder ghs[2];
609 	struct inode *inode = NULL;
610 	struct gfs2_inode *dip = GFS2_I(dir), *ip;
611 	struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
612 	struct gfs2_glock *io_gl;
613 	int error, free_vfs_inode = 1;
614 	u32 aflags = 0;
615 	unsigned blocks = 1;
616 	struct gfs2_diradd da = { .bh = NULL, .save_loc = 1, };
617 
618 	if (!name->len || name->len > GFS2_FNAMESIZE)
619 		return -ENAMETOOLONG;
620 
621 	error = gfs2_qa_get(dip);
622 	if (error)
623 		return error;
624 
625 	error = gfs2_rindex_update(sdp);
626 	if (error)
627 		goto fail;
628 
629 	error = gfs2_glock_nq_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
630 	if (error)
631 		goto fail;
632 	gfs2_holder_mark_uninitialized(ghs + 1);
633 
634 	error = create_ok(dip, name, mode);
635 	if (error)
636 		goto fail_gunlock;
637 
638 	inode = gfs2_dir_search(dir, &dentry->d_name, !S_ISREG(mode) || excl);
639 	error = PTR_ERR(inode);
640 	if (!IS_ERR(inode)) {
641 		if (S_ISDIR(inode->i_mode)) {
642 			iput(inode);
643 			inode = ERR_PTR(-EISDIR);
644 			goto fail_gunlock;
645 		}
646 		d_instantiate(dentry, inode);
647 		error = 0;
648 		if (file) {
649 			if (S_ISREG(inode->i_mode))
650 				error = finish_open(file, dentry, gfs2_open_common);
651 			else
652 				error = finish_no_open(file, NULL);
653 		}
654 		gfs2_glock_dq_uninit(ghs);
655 		goto fail;
656 	} else if (error != -ENOENT) {
657 		goto fail_gunlock;
658 	}
659 
660 	error = gfs2_diradd_alloc_required(dir, name, &da);
661 	if (error < 0)
662 		goto fail_gunlock;
663 
664 	inode = new_inode(sdp->sd_vfs);
665 	error = -ENOMEM;
666 	if (!inode)
667 		goto fail_gunlock;
668 
669 	error = posix_acl_create(dir, &mode, &default_acl, &acl);
670 	if (error)
671 		goto fail_gunlock;
672 
673 	ip = GFS2_I(inode);
674 	error = gfs2_qa_get(ip);
675 	if (error)
676 		goto fail_free_acls;
677 
678 	inode->i_mode = mode;
679 	set_nlink(inode, S_ISDIR(mode) ? 2 : 1);
680 	inode->i_rdev = dev;
681 	inode->i_size = size;
682 	inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
683 	munge_mode_uid_gid(dip, inode);
684 	check_and_update_goal(dip);
685 	ip->i_goal = dip->i_goal;
686 	ip->i_diskflags = 0;
687 	ip->i_eattr = 0;
688 	ip->i_height = 0;
689 	ip->i_depth = 0;
690 	ip->i_entries = 0;
691 	ip->i_no_addr = 0; /* Temporarily zero until real addr is assigned */
692 
693 	switch(mode & S_IFMT) {
694 	case S_IFREG:
695 		if ((dip->i_diskflags & GFS2_DIF_INHERIT_JDATA) ||
696 		    gfs2_tune_get(sdp, gt_new_files_jdata))
697 			ip->i_diskflags |= GFS2_DIF_JDATA;
698 		gfs2_set_aops(inode);
699 		break;
700 	case S_IFDIR:
701 		ip->i_diskflags |= (dip->i_diskflags & GFS2_DIF_INHERIT_JDATA);
702 		ip->i_diskflags |= GFS2_DIF_JDATA;
703 		ip->i_entries = 2;
704 		break;
705 	}
706 
707 	/* Force SYSTEM flag on all files and subdirs of a SYSTEM directory */
708 	if (dip->i_diskflags & GFS2_DIF_SYSTEM)
709 		ip->i_diskflags |= GFS2_DIF_SYSTEM;
710 
711 	gfs2_set_inode_flags(inode);
712 
713 	if ((GFS2_I(d_inode(sdp->sd_root_dir)) == dip) ||
714 	    (dip->i_diskflags & GFS2_DIF_TOPDIR))
715 		aflags |= GFS2_AF_ORLOV;
716 
717 	if (default_acl || acl)
718 		blocks++;
719 
720 	error = alloc_dinode(ip, aflags, &blocks);
721 	if (error)
722 		goto fail_free_inode;
723 
724 	gfs2_set_inode_blocks(inode, blocks);
725 
726 	error = gfs2_glock_get(sdp, ip->i_no_addr, &gfs2_inode_glops, CREATE, &ip->i_gl);
727 	if (error)
728 		goto fail_free_inode;
729 	flush_delayed_work(&ip->i_gl->gl_work);
730 	glock_set_object(ip->i_gl, ip);
731 
732 	error = gfs2_glock_get(sdp, ip->i_no_addr, &gfs2_iopen_glops, CREATE, &io_gl);
733 	if (error)
734 		goto fail_free_inode;
735 	gfs2_cancel_delete_work(io_gl);
736 	glock_set_object(io_gl, ip);
737 
738 	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, ghs + 1);
739 	if (error)
740 		goto fail_gunlock2;
741 
742 	error = gfs2_trans_begin(sdp, blocks, 0);
743 	if (error)
744 		goto fail_gunlock2;
745 
746 	if (blocks > 1) {
747 		ip->i_eattr = ip->i_no_addr + 1;
748 		gfs2_init_xattr(ip);
749 	}
750 	init_dinode(dip, ip, symname);
751 	gfs2_trans_end(sdp);
752 
753 	error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED, GL_EXACT, &ip->i_iopen_gh);
754 	if (error)
755 		goto fail_gunlock2;
756 
757 	gfs2_set_iop(inode);
758 	insert_inode_hash(inode);
759 
760 	free_vfs_inode = 0; /* After this point, the inode is no longer
761 			       considered free. Any failures need to undo
762 			       the gfs2 structures. */
763 	if (default_acl) {
764 		error = __gfs2_set_acl(inode, default_acl, ACL_TYPE_DEFAULT);
765 		if (error)
766 			goto fail_gunlock3;
767 		posix_acl_release(default_acl);
768 		default_acl = NULL;
769 	}
770 	if (acl) {
771 		error = __gfs2_set_acl(inode, acl, ACL_TYPE_ACCESS);
772 		if (error)
773 			goto fail_gunlock3;
774 		posix_acl_release(acl);
775 		acl = NULL;
776 	}
777 
778 	error = security_inode_init_security(&ip->i_inode, &dip->i_inode, name,
779 					     &gfs2_initxattrs, NULL);
780 	if (error)
781 		goto fail_gunlock3;
782 
783 	error = link_dinode(dip, name, ip, &da);
784 	if (error)
785 		goto fail_gunlock3;
786 
787 	mark_inode_dirty(inode);
788 	d_instantiate(dentry, inode);
789 	/* After instantiate, errors should result in evict which will destroy
790 	 * both inode and iopen glocks properly. */
791 	if (file) {
792 		file->f_mode |= FMODE_CREATED;
793 		error = finish_open(file, dentry, gfs2_open_common);
794 	}
795 	gfs2_glock_dq_uninit(ghs);
796 	gfs2_qa_put(ip);
797 	gfs2_glock_dq_uninit(ghs + 1);
798 	gfs2_glock_put(io_gl);
799 	gfs2_qa_put(dip);
800 	return error;
801 
802 fail_gunlock3:
803 	glock_clear_object(io_gl, ip);
804 	gfs2_glock_dq_uninit(&ip->i_iopen_gh);
805 fail_gunlock2:
806 	glock_clear_object(io_gl, ip);
807 	gfs2_glock_put(io_gl);
808 fail_free_inode:
809 	if (ip->i_gl) {
810 		glock_clear_object(ip->i_gl, ip);
811 		if (free_vfs_inode) /* else evict will do the put for us */
812 			gfs2_glock_put(ip->i_gl);
813 	}
814 	gfs2_rs_delete(ip, NULL);
815 	gfs2_qa_put(ip);
816 fail_free_acls:
817 	posix_acl_release(default_acl);
818 	posix_acl_release(acl);
819 fail_gunlock:
820 	gfs2_dir_no_add(&da);
821 	gfs2_glock_dq_uninit(ghs);
822 	if (!IS_ERR_OR_NULL(inode)) {
823 		clear_nlink(inode);
824 		if (!free_vfs_inode)
825 			mark_inode_dirty(inode);
826 		set_bit(free_vfs_inode ? GIF_FREE_VFS_INODE : GIF_ALLOC_FAILED,
827 			&GFS2_I(inode)->i_flags);
828 		iput(inode);
829 	}
830 	if (gfs2_holder_initialized(ghs + 1))
831 		gfs2_glock_dq_uninit(ghs + 1);
832 fail:
833 	gfs2_qa_put(dip);
834 	return error;
835 }
836 
837 /**
838  * gfs2_create - Create a file
839  * @mnt_userns: User namespace of the mount the inode was found from
840  * @dir: The directory in which to create the file
841  * @dentry: The dentry of the new file
842  * @mode: The mode of the new file
843  * @excl: Force fail if inode exists
844  *
845  * Returns: errno
846  */
847 
848 static int gfs2_create(struct user_namespace *mnt_userns, struct inode *dir,
849 		       struct dentry *dentry, umode_t mode, bool excl)
850 {
851 	return gfs2_create_inode(dir, dentry, NULL, S_IFREG | mode, 0, NULL, 0, excl);
852 }
853 
854 /**
855  * __gfs2_lookup - Look up a filename in a directory and return its inode
856  * @dir: The directory inode
857  * @dentry: The dentry of the new inode
858  * @file: File to be opened
859  *
860  *
861  * Returns: errno
862  */
863 
864 static struct dentry *__gfs2_lookup(struct inode *dir, struct dentry *dentry,
865 				    struct file *file)
866 {
867 	struct inode *inode;
868 	struct dentry *d;
869 	struct gfs2_holder gh;
870 	struct gfs2_glock *gl;
871 	int error;
872 
873 	inode = gfs2_lookupi(dir, &dentry->d_name, 0);
874 	if (inode == NULL) {
875 		d_add(dentry, NULL);
876 		return NULL;
877 	}
878 	if (IS_ERR(inode))
879 		return ERR_CAST(inode);
880 
881 	gl = GFS2_I(inode)->i_gl;
882 	error = gfs2_glock_nq_init(gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
883 	if (error) {
884 		iput(inode);
885 		return ERR_PTR(error);
886 	}
887 
888 	d = d_splice_alias(inode, dentry);
889 	if (IS_ERR(d)) {
890 		gfs2_glock_dq_uninit(&gh);
891 		return d;
892 	}
893 	if (file && S_ISREG(inode->i_mode))
894 		error = finish_open(file, dentry, gfs2_open_common);
895 
896 	gfs2_glock_dq_uninit(&gh);
897 	if (error) {
898 		dput(d);
899 		return ERR_PTR(error);
900 	}
901 	return d;
902 }
903 
904 static struct dentry *gfs2_lookup(struct inode *dir, struct dentry *dentry,
905 				  unsigned flags)
906 {
907 	return __gfs2_lookup(dir, dentry, NULL);
908 }
909 
910 /**
911  * gfs2_link - Link to a file
912  * @old_dentry: The inode to link
913  * @dir: Add link to this directory
914  * @dentry: The name of the link
915  *
916  * Link the inode in "old_dentry" into the directory "dir" with the
917  * name in "dentry".
918  *
919  * Returns: errno
920  */
921 
922 static int gfs2_link(struct dentry *old_dentry, struct inode *dir,
923 		     struct dentry *dentry)
924 {
925 	struct gfs2_inode *dip = GFS2_I(dir);
926 	struct gfs2_sbd *sdp = GFS2_SB(dir);
927 	struct inode *inode = d_inode(old_dentry);
928 	struct gfs2_inode *ip = GFS2_I(inode);
929 	struct gfs2_holder ghs[2];
930 	struct buffer_head *dibh;
931 	struct gfs2_diradd da = { .bh = NULL, .save_loc = 1, };
932 	int error;
933 
934 	if (S_ISDIR(inode->i_mode))
935 		return -EPERM;
936 
937 	error = gfs2_qa_get(dip);
938 	if (error)
939 		return error;
940 
941 	gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
942 	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + 1);
943 
944 	error = gfs2_glock_nq(ghs); /* parent */
945 	if (error)
946 		goto out_parent;
947 
948 	error = gfs2_glock_nq(ghs + 1); /* child */
949 	if (error)
950 		goto out_child;
951 
952 	error = -ENOENT;
953 	if (inode->i_nlink == 0)
954 		goto out_gunlock;
955 
956 	error = gfs2_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
957 	if (error)
958 		goto out_gunlock;
959 
960 	error = gfs2_dir_check(dir, &dentry->d_name, NULL);
961 	switch (error) {
962 	case -ENOENT:
963 		break;
964 	case 0:
965 		error = -EEXIST;
966 		goto out_gunlock;
967 	default:
968 		goto out_gunlock;
969 	}
970 
971 	error = -EINVAL;
972 	if (!dip->i_inode.i_nlink)
973 		goto out_gunlock;
974 	error = -EFBIG;
975 	if (dip->i_entries == (u32)-1)
976 		goto out_gunlock;
977 	error = -EPERM;
978 	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
979 		goto out_gunlock;
980 	error = -EINVAL;
981 	if (!ip->i_inode.i_nlink)
982 		goto out_gunlock;
983 	error = -EMLINK;
984 	if (ip->i_inode.i_nlink == (u32)-1)
985 		goto out_gunlock;
986 
987 	error = gfs2_diradd_alloc_required(dir, &dentry->d_name, &da);
988 	if (error < 0)
989 		goto out_gunlock;
990 
991 	if (da.nr_blocks) {
992 		struct gfs2_alloc_parms ap = { .target = da.nr_blocks, };
993 		error = gfs2_quota_lock_check(dip, &ap);
994 		if (error)
995 			goto out_gunlock;
996 
997 		error = gfs2_inplace_reserve(dip, &ap);
998 		if (error)
999 			goto out_gunlock_q;
1000 
1001 		error = gfs2_trans_begin(sdp, gfs2_trans_da_blks(dip, &da, 2), 0);
1002 		if (error)
1003 			goto out_ipres;
1004 	} else {
1005 		error = gfs2_trans_begin(sdp, 2 * RES_DINODE + RES_LEAF, 0);
1006 		if (error)
1007 			goto out_ipres;
1008 	}
1009 
1010 	error = gfs2_meta_inode_buffer(ip, &dibh);
1011 	if (error)
1012 		goto out_end_trans;
1013 
1014 	error = gfs2_dir_add(dir, &dentry->d_name, ip, &da);
1015 	if (error)
1016 		goto out_brelse;
1017 
1018 	gfs2_trans_add_meta(ip->i_gl, dibh);
1019 	inc_nlink(&ip->i_inode);
1020 	ip->i_inode.i_ctime = current_time(&ip->i_inode);
1021 	ihold(inode);
1022 	d_instantiate(dentry, inode);
1023 	mark_inode_dirty(inode);
1024 
1025 out_brelse:
1026 	brelse(dibh);
1027 out_end_trans:
1028 	gfs2_trans_end(sdp);
1029 out_ipres:
1030 	if (da.nr_blocks)
1031 		gfs2_inplace_release(dip);
1032 out_gunlock_q:
1033 	if (da.nr_blocks)
1034 		gfs2_quota_unlock(dip);
1035 out_gunlock:
1036 	gfs2_dir_no_add(&da);
1037 	gfs2_glock_dq(ghs + 1);
1038 out_child:
1039 	gfs2_glock_dq(ghs);
1040 out_parent:
1041 	gfs2_qa_put(dip);
1042 	gfs2_holder_uninit(ghs);
1043 	gfs2_holder_uninit(ghs + 1);
1044 	return error;
1045 }
1046 
1047 /*
1048  * gfs2_unlink_ok - check to see that a inode is still in a directory
1049  * @dip: the directory
1050  * @name: the name of the file
1051  * @ip: the inode
1052  *
1053  * Assumes that the lock on (at least) @dip is held.
1054  *
1055  * Returns: 0 if the parent/child relationship is correct, errno if it isn't
1056  */
1057 
1058 static int gfs2_unlink_ok(struct gfs2_inode *dip, const struct qstr *name,
1059 			  const struct gfs2_inode *ip)
1060 {
1061 	int error;
1062 
1063 	if (IS_IMMUTABLE(&ip->i_inode) || IS_APPEND(&ip->i_inode))
1064 		return -EPERM;
1065 
1066 	if ((dip->i_inode.i_mode & S_ISVTX) &&
1067 	    !uid_eq(dip->i_inode.i_uid, current_fsuid()) &&
1068 	    !uid_eq(ip->i_inode.i_uid, current_fsuid()) && !capable(CAP_FOWNER))
1069 		return -EPERM;
1070 
1071 	if (IS_APPEND(&dip->i_inode))
1072 		return -EPERM;
1073 
1074 	error = gfs2_permission(&init_user_ns, &dip->i_inode,
1075 				MAY_WRITE | MAY_EXEC);
1076 	if (error)
1077 		return error;
1078 
1079 	return gfs2_dir_check(&dip->i_inode, name, ip);
1080 }
1081 
1082 /**
1083  * gfs2_unlink_inode - Removes an inode from its parent dir and unlinks it
1084  * @dip: The parent directory
1085  * @dentry: The dentry to unlink
1086  *
1087  * Called with all the locks and in a transaction. This will only be
1088  * called for a directory after it has been checked to ensure it is empty.
1089  *
1090  * Returns: 0 on success, or an error
1091  */
1092 
1093 static int gfs2_unlink_inode(struct gfs2_inode *dip,
1094 			     const struct dentry *dentry)
1095 {
1096 	struct inode *inode = d_inode(dentry);
1097 	struct gfs2_inode *ip = GFS2_I(inode);
1098 	int error;
1099 
1100 	error = gfs2_dir_del(dip, dentry);
1101 	if (error)
1102 		return error;
1103 
1104 	ip->i_entries = 0;
1105 	inode->i_ctime = current_time(inode);
1106 	if (S_ISDIR(inode->i_mode))
1107 		clear_nlink(inode);
1108 	else
1109 		drop_nlink(inode);
1110 	mark_inode_dirty(inode);
1111 	if (inode->i_nlink == 0)
1112 		gfs2_unlink_di(inode);
1113 	return 0;
1114 }
1115 
1116 
1117 /**
1118  * gfs2_unlink - Unlink an inode (this does rmdir as well)
1119  * @dir: The inode of the directory containing the inode to unlink
1120  * @dentry: The file itself
1121  *
1122  * This routine uses the type of the inode as a flag to figure out
1123  * whether this is an unlink or an rmdir.
1124  *
1125  * Returns: errno
1126  */
1127 
1128 static int gfs2_unlink(struct inode *dir, struct dentry *dentry)
1129 {
1130 	struct gfs2_inode *dip = GFS2_I(dir);
1131 	struct gfs2_sbd *sdp = GFS2_SB(dir);
1132 	struct inode *inode = d_inode(dentry);
1133 	struct gfs2_inode *ip = GFS2_I(inode);
1134 	struct gfs2_holder ghs[3];
1135 	struct gfs2_rgrpd *rgd;
1136 	int error;
1137 
1138 	error = gfs2_rindex_update(sdp);
1139 	if (error)
1140 		return error;
1141 
1142 	error = -EROFS;
1143 
1144 	gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
1145 	gfs2_holder_init(ip->i_gl,  LM_ST_EXCLUSIVE, 0, ghs + 1);
1146 
1147 	rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr, 1);
1148 	if (!rgd)
1149 		goto out_inodes;
1150 
1151 	gfs2_holder_init(rgd->rd_gl, LM_ST_EXCLUSIVE, LM_FLAG_NODE_SCOPE, ghs + 2);
1152 
1153 
1154 	error = gfs2_glock_nq(ghs); /* parent */
1155 	if (error)
1156 		goto out_parent;
1157 
1158 	error = gfs2_glock_nq(ghs + 1); /* child */
1159 	if (error)
1160 		goto out_child;
1161 
1162 	error = -ENOENT;
1163 	if (inode->i_nlink == 0)
1164 		goto out_rgrp;
1165 
1166 	if (S_ISDIR(inode->i_mode)) {
1167 		error = -ENOTEMPTY;
1168 		if (ip->i_entries > 2 || inode->i_nlink > 2)
1169 			goto out_rgrp;
1170 	}
1171 
1172 	error = gfs2_glock_nq(ghs + 2); /* rgrp */
1173 	if (error)
1174 		goto out_rgrp;
1175 
1176 	error = gfs2_unlink_ok(dip, &dentry->d_name, ip);
1177 	if (error)
1178 		goto out_gunlock;
1179 
1180 	error = gfs2_trans_begin(sdp, 2*RES_DINODE + 3*RES_LEAF + RES_RG_BIT, 0);
1181 	if (error)
1182 		goto out_gunlock;
1183 
1184 	error = gfs2_unlink_inode(dip, dentry);
1185 	gfs2_trans_end(sdp);
1186 
1187 out_gunlock:
1188 	gfs2_glock_dq(ghs + 2);
1189 out_rgrp:
1190 	gfs2_glock_dq(ghs + 1);
1191 out_child:
1192 	gfs2_glock_dq(ghs);
1193 out_parent:
1194 	gfs2_holder_uninit(ghs + 2);
1195 out_inodes:
1196 	gfs2_holder_uninit(ghs + 1);
1197 	gfs2_holder_uninit(ghs);
1198 	return error;
1199 }
1200 
1201 /**
1202  * gfs2_symlink - Create a symlink
1203  * @mnt_userns: User namespace of the mount the inode was found from
1204  * @dir: The directory to create the symlink in
1205  * @dentry: The dentry to put the symlink in
1206  * @symname: The thing which the link points to
1207  *
1208  * Returns: errno
1209  */
1210 
1211 static int gfs2_symlink(struct user_namespace *mnt_userns, struct inode *dir,
1212 			struct dentry *dentry, const char *symname)
1213 {
1214 	unsigned int size;
1215 
1216 	size = strlen(symname);
1217 	if (size >= gfs2_max_stuffed_size(GFS2_I(dir)))
1218 		return -ENAMETOOLONG;
1219 
1220 	return gfs2_create_inode(dir, dentry, NULL, S_IFLNK | S_IRWXUGO, 0, symname, size, 0);
1221 }
1222 
1223 /**
1224  * gfs2_mkdir - Make a directory
1225  * @mnt_userns: User namespace of the mount the inode was found from
1226  * @dir: The parent directory of the new one
1227  * @dentry: The dentry of the new directory
1228  * @mode: The mode of the new directory
1229  *
1230  * Returns: errno
1231  */
1232 
1233 static int gfs2_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
1234 		      struct dentry *dentry, umode_t mode)
1235 {
1236 	unsigned dsize = gfs2_max_stuffed_size(GFS2_I(dir));
1237 	return gfs2_create_inode(dir, dentry, NULL, S_IFDIR | mode, 0, NULL, dsize, 0);
1238 }
1239 
1240 /**
1241  * gfs2_mknod - Make a special file
1242  * @mnt_userns: User namespace of the mount the inode was found from
1243  * @dir: The directory in which the special file will reside
1244  * @dentry: The dentry of the special file
1245  * @mode: The mode of the special file
1246  * @dev: The device specification of the special file
1247  *
1248  */
1249 
1250 static int gfs2_mknod(struct user_namespace *mnt_userns, struct inode *dir,
1251 		      struct dentry *dentry, umode_t mode, dev_t dev)
1252 {
1253 	return gfs2_create_inode(dir, dentry, NULL, mode, dev, NULL, 0, 0);
1254 }
1255 
1256 /**
1257  * gfs2_atomic_open - Atomically open a file
1258  * @dir: The directory
1259  * @dentry: The proposed new entry
1260  * @file: The proposed new struct file
1261  * @flags: open flags
1262  * @mode: File mode
1263  *
1264  * Returns: error code or 0 for success
1265  */
1266 
1267 static int gfs2_atomic_open(struct inode *dir, struct dentry *dentry,
1268 			    struct file *file, unsigned flags,
1269 			    umode_t mode)
1270 {
1271 	struct dentry *d;
1272 	bool excl = !!(flags & O_EXCL);
1273 
1274 	if (!d_in_lookup(dentry))
1275 		goto skip_lookup;
1276 
1277 	d = __gfs2_lookup(dir, dentry, file);
1278 	if (IS_ERR(d))
1279 		return PTR_ERR(d);
1280 	if (d != NULL)
1281 		dentry = d;
1282 	if (d_really_is_positive(dentry)) {
1283 		if (!(file->f_mode & FMODE_OPENED))
1284 			return finish_no_open(file, d);
1285 		dput(d);
1286 		return excl && (flags & O_CREAT) ? -EEXIST : 0;
1287 	}
1288 
1289 	BUG_ON(d != NULL);
1290 
1291 skip_lookup:
1292 	if (!(flags & O_CREAT))
1293 		return -ENOENT;
1294 
1295 	return gfs2_create_inode(dir, dentry, file, S_IFREG | mode, 0, NULL, 0, excl);
1296 }
1297 
1298 /*
1299  * gfs2_ok_to_move - check if it's ok to move a directory to another directory
1300  * @this: move this
1301  * @to: to here
1302  *
1303  * Follow @to back to the root and make sure we don't encounter @this
1304  * Assumes we already hold the rename lock.
1305  *
1306  * Returns: errno
1307  */
1308 
1309 static int gfs2_ok_to_move(struct gfs2_inode *this, struct gfs2_inode *to)
1310 {
1311 	struct inode *dir = &to->i_inode;
1312 	struct super_block *sb = dir->i_sb;
1313 	struct inode *tmp;
1314 	int error = 0;
1315 
1316 	igrab(dir);
1317 
1318 	for (;;) {
1319 		if (dir == &this->i_inode) {
1320 			error = -EINVAL;
1321 			break;
1322 		}
1323 		if (dir == d_inode(sb->s_root)) {
1324 			error = 0;
1325 			break;
1326 		}
1327 
1328 		tmp = gfs2_lookupi(dir, &gfs2_qdotdot, 1);
1329 		if (!tmp) {
1330 			error = -ENOENT;
1331 			break;
1332 		}
1333 		if (IS_ERR(tmp)) {
1334 			error = PTR_ERR(tmp);
1335 			break;
1336 		}
1337 
1338 		iput(dir);
1339 		dir = tmp;
1340 	}
1341 
1342 	iput(dir);
1343 
1344 	return error;
1345 }
1346 
1347 /**
1348  * update_moved_ino - Update an inode that's being moved
1349  * @ip: The inode being moved
1350  * @ndip: The parent directory of the new filename
1351  * @dir_rename: True of ip is a directory
1352  *
1353  * Returns: errno
1354  */
1355 
1356 static int update_moved_ino(struct gfs2_inode *ip, struct gfs2_inode *ndip,
1357 			    int dir_rename)
1358 {
1359 	if (dir_rename)
1360 		return gfs2_dir_mvino(ip, &gfs2_qdotdot, ndip, DT_DIR);
1361 
1362 	ip->i_inode.i_ctime = current_time(&ip->i_inode);
1363 	mark_inode_dirty_sync(&ip->i_inode);
1364 	return 0;
1365 }
1366 
1367 
1368 /**
1369  * gfs2_rename - Rename a file
1370  * @odir: Parent directory of old file name
1371  * @odentry: The old dentry of the file
1372  * @ndir: Parent directory of new file name
1373  * @ndentry: The new dentry of the file
1374  *
1375  * Returns: errno
1376  */
1377 
1378 static int gfs2_rename(struct inode *odir, struct dentry *odentry,
1379 		       struct inode *ndir, struct dentry *ndentry)
1380 {
1381 	struct gfs2_inode *odip = GFS2_I(odir);
1382 	struct gfs2_inode *ndip = GFS2_I(ndir);
1383 	struct gfs2_inode *ip = GFS2_I(d_inode(odentry));
1384 	struct gfs2_inode *nip = NULL;
1385 	struct gfs2_sbd *sdp = GFS2_SB(odir);
1386 	struct gfs2_holder ghs[4], r_gh, rd_gh;
1387 	struct gfs2_rgrpd *nrgd;
1388 	unsigned int num_gh;
1389 	int dir_rename = 0;
1390 	struct gfs2_diradd da = { .nr_blocks = 0, .save_loc = 0, };
1391 	unsigned int x;
1392 	int error;
1393 
1394 	gfs2_holder_mark_uninitialized(&r_gh);
1395 	gfs2_holder_mark_uninitialized(&rd_gh);
1396 	if (d_really_is_positive(ndentry)) {
1397 		nip = GFS2_I(d_inode(ndentry));
1398 		if (ip == nip)
1399 			return 0;
1400 	}
1401 
1402 	error = gfs2_rindex_update(sdp);
1403 	if (error)
1404 		return error;
1405 
1406 	error = gfs2_qa_get(ndip);
1407 	if (error)
1408 		return error;
1409 
1410 	if (odip != ndip) {
1411 		error = gfs2_glock_nq_init(sdp->sd_rename_gl, LM_ST_EXCLUSIVE,
1412 					   0, &r_gh);
1413 		if (error)
1414 			goto out;
1415 
1416 		if (S_ISDIR(ip->i_inode.i_mode)) {
1417 			dir_rename = 1;
1418 			/* don't move a directory into its subdir */
1419 			error = gfs2_ok_to_move(ip, ndip);
1420 			if (error)
1421 				goto out_gunlock_r;
1422 		}
1423 	}
1424 
1425 	num_gh = 1;
1426 	gfs2_holder_init(odip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC, ghs);
1427 	if (odip != ndip) {
1428 		gfs2_holder_init(ndip->i_gl, LM_ST_EXCLUSIVE,GL_ASYNC,
1429 				 ghs + num_gh);
1430 		num_gh++;
1431 	}
1432 	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC, ghs + num_gh);
1433 	num_gh++;
1434 
1435 	if (nip) {
1436 		gfs2_holder_init(nip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC,
1437 				 ghs + num_gh);
1438 		num_gh++;
1439 	}
1440 
1441 	for (x = 0; x < num_gh; x++) {
1442 		error = gfs2_glock_nq(ghs + x);
1443 		if (error)
1444 			goto out_gunlock;
1445 	}
1446 	error = gfs2_glock_async_wait(num_gh, ghs);
1447 	if (error)
1448 		goto out_gunlock;
1449 
1450 	if (nip) {
1451 		/* Grab the resource group glock for unlink flag twiddling.
1452 		 * This is the case where the target dinode already exists
1453 		 * so we unlink before doing the rename.
1454 		 */
1455 		nrgd = gfs2_blk2rgrpd(sdp, nip->i_no_addr, 1);
1456 		if (!nrgd) {
1457 			error = -ENOENT;
1458 			goto out_gunlock;
1459 		}
1460 		error = gfs2_glock_nq_init(nrgd->rd_gl, LM_ST_EXCLUSIVE,
1461 					   LM_FLAG_NODE_SCOPE, &rd_gh);
1462 		if (error)
1463 			goto out_gunlock;
1464 	}
1465 
1466 	error = -ENOENT;
1467 	if (ip->i_inode.i_nlink == 0)
1468 		goto out_gunlock;
1469 
1470 	/* Check out the old directory */
1471 
1472 	error = gfs2_unlink_ok(odip, &odentry->d_name, ip);
1473 	if (error)
1474 		goto out_gunlock;
1475 
1476 	/* Check out the new directory */
1477 
1478 	if (nip) {
1479 		error = gfs2_unlink_ok(ndip, &ndentry->d_name, nip);
1480 		if (error)
1481 			goto out_gunlock;
1482 
1483 		if (nip->i_inode.i_nlink == 0) {
1484 			error = -EAGAIN;
1485 			goto out_gunlock;
1486 		}
1487 
1488 		if (S_ISDIR(nip->i_inode.i_mode)) {
1489 			if (nip->i_entries < 2) {
1490 				gfs2_consist_inode(nip);
1491 				error = -EIO;
1492 				goto out_gunlock;
1493 			}
1494 			if (nip->i_entries > 2) {
1495 				error = -ENOTEMPTY;
1496 				goto out_gunlock;
1497 			}
1498 		}
1499 	} else {
1500 		error = gfs2_permission(&init_user_ns, ndir,
1501 					MAY_WRITE | MAY_EXEC);
1502 		if (error)
1503 			goto out_gunlock;
1504 
1505 		error = gfs2_dir_check(ndir, &ndentry->d_name, NULL);
1506 		switch (error) {
1507 		case -ENOENT:
1508 			error = 0;
1509 			break;
1510 		case 0:
1511 			error = -EEXIST;
1512 			goto out_gunlock;
1513 		default:
1514 			goto out_gunlock;
1515 		}
1516 
1517 		if (odip != ndip) {
1518 			if (!ndip->i_inode.i_nlink) {
1519 				error = -ENOENT;
1520 				goto out_gunlock;
1521 			}
1522 			if (ndip->i_entries == (u32)-1) {
1523 				error = -EFBIG;
1524 				goto out_gunlock;
1525 			}
1526 			if (S_ISDIR(ip->i_inode.i_mode) &&
1527 			    ndip->i_inode.i_nlink == (u32)-1) {
1528 				error = -EMLINK;
1529 				goto out_gunlock;
1530 			}
1531 		}
1532 	}
1533 
1534 	/* Check out the dir to be renamed */
1535 
1536 	if (dir_rename) {
1537 		error = gfs2_permission(&init_user_ns, d_inode(odentry),
1538 					MAY_WRITE);
1539 		if (error)
1540 			goto out_gunlock;
1541 	}
1542 
1543 	if (nip == NULL) {
1544 		error = gfs2_diradd_alloc_required(ndir, &ndentry->d_name, &da);
1545 		if (error)
1546 			goto out_gunlock;
1547 	}
1548 
1549 	if (da.nr_blocks) {
1550 		struct gfs2_alloc_parms ap = { .target = da.nr_blocks, };
1551 		error = gfs2_quota_lock_check(ndip, &ap);
1552 		if (error)
1553 			goto out_gunlock;
1554 
1555 		error = gfs2_inplace_reserve(ndip, &ap);
1556 		if (error)
1557 			goto out_gunlock_q;
1558 
1559 		error = gfs2_trans_begin(sdp, gfs2_trans_da_blks(ndip, &da, 4) +
1560 					 4 * RES_LEAF + 4, 0);
1561 		if (error)
1562 			goto out_ipreserv;
1563 	} else {
1564 		error = gfs2_trans_begin(sdp, 4 * RES_DINODE +
1565 					 5 * RES_LEAF + 4, 0);
1566 		if (error)
1567 			goto out_gunlock;
1568 	}
1569 
1570 	/* Remove the target file, if it exists */
1571 
1572 	if (nip)
1573 		error = gfs2_unlink_inode(ndip, ndentry);
1574 
1575 	error = update_moved_ino(ip, ndip, dir_rename);
1576 	if (error)
1577 		goto out_end_trans;
1578 
1579 	error = gfs2_dir_del(odip, odentry);
1580 	if (error)
1581 		goto out_end_trans;
1582 
1583 	error = gfs2_dir_add(ndir, &ndentry->d_name, ip, &da);
1584 	if (error)
1585 		goto out_end_trans;
1586 
1587 out_end_trans:
1588 	gfs2_trans_end(sdp);
1589 out_ipreserv:
1590 	if (da.nr_blocks)
1591 		gfs2_inplace_release(ndip);
1592 out_gunlock_q:
1593 	if (da.nr_blocks)
1594 		gfs2_quota_unlock(ndip);
1595 out_gunlock:
1596 	gfs2_dir_no_add(&da);
1597 	if (gfs2_holder_initialized(&rd_gh))
1598 		gfs2_glock_dq_uninit(&rd_gh);
1599 
1600 	while (x--) {
1601 		if (gfs2_holder_queued(ghs + x))
1602 			gfs2_glock_dq(ghs + x);
1603 		gfs2_holder_uninit(ghs + x);
1604 	}
1605 out_gunlock_r:
1606 	if (gfs2_holder_initialized(&r_gh))
1607 		gfs2_glock_dq_uninit(&r_gh);
1608 out:
1609 	gfs2_qa_put(ndip);
1610 	return error;
1611 }
1612 
1613 /**
1614  * gfs2_exchange - exchange two files
1615  * @odir: Parent directory of old file name
1616  * @odentry: The old dentry of the file
1617  * @ndir: Parent directory of new file name
1618  * @ndentry: The new dentry of the file
1619  * @flags: The rename flags
1620  *
1621  * Returns: errno
1622  */
1623 
1624 static int gfs2_exchange(struct inode *odir, struct dentry *odentry,
1625 			 struct inode *ndir, struct dentry *ndentry,
1626 			 unsigned int flags)
1627 {
1628 	struct gfs2_inode *odip = GFS2_I(odir);
1629 	struct gfs2_inode *ndip = GFS2_I(ndir);
1630 	struct gfs2_inode *oip = GFS2_I(odentry->d_inode);
1631 	struct gfs2_inode *nip = GFS2_I(ndentry->d_inode);
1632 	struct gfs2_sbd *sdp = GFS2_SB(odir);
1633 	struct gfs2_holder ghs[4], r_gh;
1634 	unsigned int num_gh;
1635 	unsigned int x;
1636 	umode_t old_mode = oip->i_inode.i_mode;
1637 	umode_t new_mode = nip->i_inode.i_mode;
1638 	int error;
1639 
1640 	gfs2_holder_mark_uninitialized(&r_gh);
1641 	error = gfs2_rindex_update(sdp);
1642 	if (error)
1643 		return error;
1644 
1645 	if (odip != ndip) {
1646 		error = gfs2_glock_nq_init(sdp->sd_rename_gl, LM_ST_EXCLUSIVE,
1647 					   0, &r_gh);
1648 		if (error)
1649 			goto out;
1650 
1651 		if (S_ISDIR(old_mode)) {
1652 			/* don't move a directory into its subdir */
1653 			error = gfs2_ok_to_move(oip, ndip);
1654 			if (error)
1655 				goto out_gunlock_r;
1656 		}
1657 
1658 		if (S_ISDIR(new_mode)) {
1659 			/* don't move a directory into its subdir */
1660 			error = gfs2_ok_to_move(nip, odip);
1661 			if (error)
1662 				goto out_gunlock_r;
1663 		}
1664 	}
1665 
1666 	num_gh = 1;
1667 	gfs2_holder_init(odip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC, ghs);
1668 	if (odip != ndip) {
1669 		gfs2_holder_init(ndip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC,
1670 				 ghs + num_gh);
1671 		num_gh++;
1672 	}
1673 	gfs2_holder_init(oip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC, ghs + num_gh);
1674 	num_gh++;
1675 
1676 	gfs2_holder_init(nip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC, ghs + num_gh);
1677 	num_gh++;
1678 
1679 	for (x = 0; x < num_gh; x++) {
1680 		error = gfs2_glock_nq(ghs + x);
1681 		if (error)
1682 			goto out_gunlock;
1683 	}
1684 
1685 	error = gfs2_glock_async_wait(num_gh, ghs);
1686 	if (error)
1687 		goto out_gunlock;
1688 
1689 	error = -ENOENT;
1690 	if (oip->i_inode.i_nlink == 0 || nip->i_inode.i_nlink == 0)
1691 		goto out_gunlock;
1692 
1693 	error = gfs2_unlink_ok(odip, &odentry->d_name, oip);
1694 	if (error)
1695 		goto out_gunlock;
1696 	error = gfs2_unlink_ok(ndip, &ndentry->d_name, nip);
1697 	if (error)
1698 		goto out_gunlock;
1699 
1700 	if (S_ISDIR(old_mode)) {
1701 		error = gfs2_permission(&init_user_ns, odentry->d_inode,
1702 					MAY_WRITE);
1703 		if (error)
1704 			goto out_gunlock;
1705 	}
1706 	if (S_ISDIR(new_mode)) {
1707 		error = gfs2_permission(&init_user_ns, ndentry->d_inode,
1708 					MAY_WRITE);
1709 		if (error)
1710 			goto out_gunlock;
1711 	}
1712 	error = gfs2_trans_begin(sdp, 4 * RES_DINODE + 4 * RES_LEAF, 0);
1713 	if (error)
1714 		goto out_gunlock;
1715 
1716 	error = update_moved_ino(oip, ndip, S_ISDIR(old_mode));
1717 	if (error)
1718 		goto out_end_trans;
1719 
1720 	error = update_moved_ino(nip, odip, S_ISDIR(new_mode));
1721 	if (error)
1722 		goto out_end_trans;
1723 
1724 	error = gfs2_dir_mvino(ndip, &ndentry->d_name, oip,
1725 			       IF2DT(old_mode));
1726 	if (error)
1727 		goto out_end_trans;
1728 
1729 	error = gfs2_dir_mvino(odip, &odentry->d_name, nip,
1730 			       IF2DT(new_mode));
1731 	if (error)
1732 		goto out_end_trans;
1733 
1734 	if (odip != ndip) {
1735 		if (S_ISDIR(new_mode) && !S_ISDIR(old_mode)) {
1736 			inc_nlink(&odip->i_inode);
1737 			drop_nlink(&ndip->i_inode);
1738 		} else if (S_ISDIR(old_mode) && !S_ISDIR(new_mode)) {
1739 			inc_nlink(&ndip->i_inode);
1740 			drop_nlink(&odip->i_inode);
1741 		}
1742 	}
1743 	mark_inode_dirty(&ndip->i_inode);
1744 	if (odip != ndip)
1745 		mark_inode_dirty(&odip->i_inode);
1746 
1747 out_end_trans:
1748 	gfs2_trans_end(sdp);
1749 out_gunlock:
1750 	while (x--) {
1751 		if (gfs2_holder_queued(ghs + x))
1752 			gfs2_glock_dq(ghs + x);
1753 		gfs2_holder_uninit(ghs + x);
1754 	}
1755 out_gunlock_r:
1756 	if (gfs2_holder_initialized(&r_gh))
1757 		gfs2_glock_dq_uninit(&r_gh);
1758 out:
1759 	return error;
1760 }
1761 
1762 static int gfs2_rename2(struct user_namespace *mnt_userns, struct inode *odir,
1763 			struct dentry *odentry, struct inode *ndir,
1764 			struct dentry *ndentry, unsigned int flags)
1765 {
1766 	flags &= ~RENAME_NOREPLACE;
1767 
1768 	if (flags & ~RENAME_EXCHANGE)
1769 		return -EINVAL;
1770 
1771 	if (flags & RENAME_EXCHANGE)
1772 		return gfs2_exchange(odir, odentry, ndir, ndentry, flags);
1773 
1774 	return gfs2_rename(odir, odentry, ndir, ndentry);
1775 }
1776 
1777 /**
1778  * gfs2_get_link - Follow a symbolic link
1779  * @dentry: The dentry of the link
1780  * @inode: The inode of the link
1781  * @done: destructor for return value
1782  *
1783  * This can handle symlinks of any size.
1784  *
1785  * Returns: 0 on success or error code
1786  */
1787 
1788 static const char *gfs2_get_link(struct dentry *dentry,
1789 				 struct inode *inode,
1790 				 struct delayed_call *done)
1791 {
1792 	struct gfs2_inode *ip = GFS2_I(inode);
1793 	struct gfs2_holder i_gh;
1794 	struct buffer_head *dibh;
1795 	unsigned int size;
1796 	char *buf;
1797 	int error;
1798 
1799 	if (!dentry)
1800 		return ERR_PTR(-ECHILD);
1801 
1802 	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
1803 	error = gfs2_glock_nq(&i_gh);
1804 	if (error) {
1805 		gfs2_holder_uninit(&i_gh);
1806 		return ERR_PTR(error);
1807 	}
1808 
1809 	size = (unsigned int)i_size_read(&ip->i_inode);
1810 	if (size == 0) {
1811 		gfs2_consist_inode(ip);
1812 		buf = ERR_PTR(-EIO);
1813 		goto out;
1814 	}
1815 
1816 	error = gfs2_meta_inode_buffer(ip, &dibh);
1817 	if (error) {
1818 		buf = ERR_PTR(error);
1819 		goto out;
1820 	}
1821 
1822 	buf = kzalloc(size + 1, GFP_NOFS);
1823 	if (!buf)
1824 		buf = ERR_PTR(-ENOMEM);
1825 	else
1826 		memcpy(buf, dibh->b_data + sizeof(struct gfs2_dinode), size);
1827 	brelse(dibh);
1828 out:
1829 	gfs2_glock_dq_uninit(&i_gh);
1830 	if (!IS_ERR(buf))
1831 		set_delayed_call(done, kfree_link, buf);
1832 	return buf;
1833 }
1834 
1835 /**
1836  * gfs2_permission
1837  * @mnt_userns: User namespace of the mount the inode was found from
1838  * @inode: The inode
1839  * @mask: The mask to be tested
1840  *
1841  * This may be called from the VFS directly, or from within GFS2 with the
1842  * inode locked, so we look to see if the glock is already locked and only
1843  * lock the glock if its not already been done.
1844  *
1845  * Returns: errno
1846  */
1847 
1848 int gfs2_permission(struct user_namespace *mnt_userns, struct inode *inode,
1849 		    int mask)
1850 {
1851 	struct gfs2_inode *ip;
1852 	struct gfs2_holder i_gh;
1853 	int error;
1854 
1855 	gfs2_holder_mark_uninitialized(&i_gh);
1856 	ip = GFS2_I(inode);
1857 	if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
1858 		if (mask & MAY_NOT_BLOCK)
1859 			return -ECHILD;
1860 		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
1861 		if (error)
1862 			return error;
1863 	}
1864 
1865 	if ((mask & MAY_WRITE) && IS_IMMUTABLE(inode))
1866 		error = -EPERM;
1867 	else
1868 		error = generic_permission(&init_user_ns, inode, mask);
1869 	if (gfs2_holder_initialized(&i_gh))
1870 		gfs2_glock_dq_uninit(&i_gh);
1871 
1872 	return error;
1873 }
1874 
1875 static int __gfs2_setattr_simple(struct inode *inode, struct iattr *attr)
1876 {
1877 	setattr_copy(&init_user_ns, inode, attr);
1878 	mark_inode_dirty(inode);
1879 	return 0;
1880 }
1881 
1882 static int gfs2_setattr_simple(struct inode *inode, struct iattr *attr)
1883 {
1884 	int error;
1885 
1886 	if (current->journal_info)
1887 		return __gfs2_setattr_simple(inode, attr);
1888 
1889 	error = gfs2_trans_begin(GFS2_SB(inode), RES_DINODE, 0);
1890 	if (error)
1891 		return error;
1892 
1893 	error = __gfs2_setattr_simple(inode, attr);
1894 	gfs2_trans_end(GFS2_SB(inode));
1895 	return error;
1896 }
1897 
1898 static int setattr_chown(struct inode *inode, struct iattr *attr)
1899 {
1900 	struct gfs2_inode *ip = GFS2_I(inode);
1901 	struct gfs2_sbd *sdp = GFS2_SB(inode);
1902 	kuid_t ouid, nuid;
1903 	kgid_t ogid, ngid;
1904 	int error;
1905 	struct gfs2_alloc_parms ap;
1906 
1907 	ouid = inode->i_uid;
1908 	ogid = inode->i_gid;
1909 	nuid = attr->ia_uid;
1910 	ngid = attr->ia_gid;
1911 
1912 	if (!(attr->ia_valid & ATTR_UID) || uid_eq(ouid, nuid))
1913 		ouid = nuid = NO_UID_QUOTA_CHANGE;
1914 	if (!(attr->ia_valid & ATTR_GID) || gid_eq(ogid, ngid))
1915 		ogid = ngid = NO_GID_QUOTA_CHANGE;
1916 	error = gfs2_qa_get(ip);
1917 	if (error)
1918 		return error;
1919 
1920 	error = gfs2_rindex_update(sdp);
1921 	if (error)
1922 		goto out;
1923 
1924 	error = gfs2_quota_lock(ip, nuid, ngid);
1925 	if (error)
1926 		goto out;
1927 
1928 	ap.target = gfs2_get_inode_blocks(&ip->i_inode);
1929 
1930 	if (!uid_eq(ouid, NO_UID_QUOTA_CHANGE) ||
1931 	    !gid_eq(ogid, NO_GID_QUOTA_CHANGE)) {
1932 		error = gfs2_quota_check(ip, nuid, ngid, &ap);
1933 		if (error)
1934 			goto out_gunlock_q;
1935 	}
1936 
1937 	error = gfs2_trans_begin(sdp, RES_DINODE + 2 * RES_QUOTA, 0);
1938 	if (error)
1939 		goto out_gunlock_q;
1940 
1941 	error = gfs2_setattr_simple(inode, attr);
1942 	if (error)
1943 		goto out_end_trans;
1944 
1945 	if (!uid_eq(ouid, NO_UID_QUOTA_CHANGE) ||
1946 	    !gid_eq(ogid, NO_GID_QUOTA_CHANGE)) {
1947 		gfs2_quota_change(ip, -(s64)ap.target, ouid, ogid);
1948 		gfs2_quota_change(ip, ap.target, nuid, ngid);
1949 	}
1950 
1951 out_end_trans:
1952 	gfs2_trans_end(sdp);
1953 out_gunlock_q:
1954 	gfs2_quota_unlock(ip);
1955 out:
1956 	gfs2_qa_put(ip);
1957 	return error;
1958 }
1959 
1960 /**
1961  * gfs2_setattr - Change attributes on an inode
1962  * @mnt_userns: User namespace of the mount the inode was found from
1963  * @dentry: The dentry which is changing
1964  * @attr: The structure describing the change
1965  *
1966  * The VFS layer wants to change one or more of an inodes attributes.  Write
1967  * that change out to disk.
1968  *
1969  * Returns: errno
1970  */
1971 
1972 static int gfs2_setattr(struct user_namespace *mnt_userns,
1973 			struct dentry *dentry, struct iattr *attr)
1974 {
1975 	struct inode *inode = d_inode(dentry);
1976 	struct gfs2_inode *ip = GFS2_I(inode);
1977 	struct gfs2_holder i_gh;
1978 	int error;
1979 
1980 	error = gfs2_qa_get(ip);
1981 	if (error)
1982 		return error;
1983 
1984 	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1985 	if (error)
1986 		goto out;
1987 
1988 	error = -EPERM;
1989 	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
1990 		goto error;
1991 
1992 	error = setattr_prepare(&init_user_ns, dentry, attr);
1993 	if (error)
1994 		goto error;
1995 
1996 	if (attr->ia_valid & ATTR_SIZE)
1997 		error = gfs2_setattr_size(inode, attr->ia_size);
1998 	else if (attr->ia_valid & (ATTR_UID | ATTR_GID))
1999 		error = setattr_chown(inode, attr);
2000 	else {
2001 		error = gfs2_setattr_simple(inode, attr);
2002 		if (!error && attr->ia_valid & ATTR_MODE)
2003 			error = posix_acl_chmod(&init_user_ns, inode,
2004 						inode->i_mode);
2005 	}
2006 
2007 error:
2008 	if (!error)
2009 		mark_inode_dirty(inode);
2010 	gfs2_glock_dq_uninit(&i_gh);
2011 out:
2012 	gfs2_qa_put(ip);
2013 	return error;
2014 }
2015 
2016 /**
2017  * gfs2_getattr - Read out an inode's attributes
2018  * @mnt_userns:	user namespace of the mount the inode was found from
2019  * @path: Object to query
2020  * @stat: The inode's stats
2021  * @request_mask: Mask of STATX_xxx flags indicating the caller's interests
2022  * @flags: AT_STATX_xxx setting
2023  *
2024  * This may be called from the VFS directly, or from within GFS2 with the
2025  * inode locked, so we look to see if the glock is already locked and only
2026  * lock the glock if its not already been done. Note that its the NFS
2027  * readdirplus operation which causes this to be called (from filldir)
2028  * with the glock already held.
2029  *
2030  * Returns: errno
2031  */
2032 
2033 static int gfs2_getattr(struct user_namespace *mnt_userns,
2034 			const struct path *path, struct kstat *stat,
2035 			u32 request_mask, unsigned int flags)
2036 {
2037 	struct inode *inode = d_inode(path->dentry);
2038 	struct gfs2_inode *ip = GFS2_I(inode);
2039 	struct gfs2_holder gh;
2040 	u32 gfsflags;
2041 	int error;
2042 
2043 	gfs2_holder_mark_uninitialized(&gh);
2044 	if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
2045 		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
2046 		if (error)
2047 			return error;
2048 	}
2049 
2050 	gfsflags = ip->i_diskflags;
2051 	if (gfsflags & GFS2_DIF_APPENDONLY)
2052 		stat->attributes |= STATX_ATTR_APPEND;
2053 	if (gfsflags & GFS2_DIF_IMMUTABLE)
2054 		stat->attributes |= STATX_ATTR_IMMUTABLE;
2055 
2056 	stat->attributes_mask |= (STATX_ATTR_APPEND |
2057 				  STATX_ATTR_COMPRESSED |
2058 				  STATX_ATTR_ENCRYPTED |
2059 				  STATX_ATTR_IMMUTABLE |
2060 				  STATX_ATTR_NODUMP);
2061 
2062 	generic_fillattr(&init_user_ns, inode, stat);
2063 
2064 	if (gfs2_holder_initialized(&gh))
2065 		gfs2_glock_dq_uninit(&gh);
2066 
2067 	return 0;
2068 }
2069 
2070 static int gfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2071 		       u64 start, u64 len)
2072 {
2073 	struct gfs2_inode *ip = GFS2_I(inode);
2074 	struct gfs2_holder gh;
2075 	int ret;
2076 
2077 	inode_lock_shared(inode);
2078 
2079 	ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
2080 	if (ret)
2081 		goto out;
2082 
2083 	ret = iomap_fiemap(inode, fieinfo, start, len, &gfs2_iomap_ops);
2084 
2085 	gfs2_glock_dq_uninit(&gh);
2086 
2087 out:
2088 	inode_unlock_shared(inode);
2089 	return ret;
2090 }
2091 
2092 loff_t gfs2_seek_data(struct file *file, loff_t offset)
2093 {
2094 	struct inode *inode = file->f_mapping->host;
2095 	struct gfs2_inode *ip = GFS2_I(inode);
2096 	struct gfs2_holder gh;
2097 	loff_t ret;
2098 
2099 	inode_lock_shared(inode);
2100 	ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
2101 	if (!ret)
2102 		ret = iomap_seek_data(inode, offset, &gfs2_iomap_ops);
2103 	gfs2_glock_dq_uninit(&gh);
2104 	inode_unlock_shared(inode);
2105 
2106 	if (ret < 0)
2107 		return ret;
2108 	return vfs_setpos(file, ret, inode->i_sb->s_maxbytes);
2109 }
2110 
2111 loff_t gfs2_seek_hole(struct file *file, loff_t offset)
2112 {
2113 	struct inode *inode = file->f_mapping->host;
2114 	struct gfs2_inode *ip = GFS2_I(inode);
2115 	struct gfs2_holder gh;
2116 	loff_t ret;
2117 
2118 	inode_lock_shared(inode);
2119 	ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
2120 	if (!ret)
2121 		ret = iomap_seek_hole(inode, offset, &gfs2_iomap_ops);
2122 	gfs2_glock_dq_uninit(&gh);
2123 	inode_unlock_shared(inode);
2124 
2125 	if (ret < 0)
2126 		return ret;
2127 	return vfs_setpos(file, ret, inode->i_sb->s_maxbytes);
2128 }
2129 
2130 static int gfs2_update_time(struct inode *inode, struct timespec64 *time,
2131 			    int flags)
2132 {
2133 	struct gfs2_inode *ip = GFS2_I(inode);
2134 	struct gfs2_glock *gl = ip->i_gl;
2135 	struct gfs2_holder *gh;
2136 	int error;
2137 
2138 	gh = gfs2_glock_is_locked_by_me(gl);
2139 	if (gh && !gfs2_glock_is_held_excl(gl)) {
2140 		gfs2_glock_dq(gh);
2141 		gfs2_holder_reinit(LM_ST_EXCLUSIVE, 0, gh);
2142 		error = gfs2_glock_nq(gh);
2143 		if (error)
2144 			return error;
2145 	}
2146 	return generic_update_time(inode, time, flags);
2147 }
2148 
2149 static const struct inode_operations gfs2_file_iops = {
2150 	.permission = gfs2_permission,
2151 	.setattr = gfs2_setattr,
2152 	.getattr = gfs2_getattr,
2153 	.listxattr = gfs2_listxattr,
2154 	.fiemap = gfs2_fiemap,
2155 	.get_acl = gfs2_get_acl,
2156 	.set_acl = gfs2_set_acl,
2157 	.update_time = gfs2_update_time,
2158 	.fileattr_get = gfs2_fileattr_get,
2159 	.fileattr_set = gfs2_fileattr_set,
2160 };
2161 
2162 static const struct inode_operations gfs2_dir_iops = {
2163 	.create = gfs2_create,
2164 	.lookup = gfs2_lookup,
2165 	.link = gfs2_link,
2166 	.unlink = gfs2_unlink,
2167 	.symlink = gfs2_symlink,
2168 	.mkdir = gfs2_mkdir,
2169 	.rmdir = gfs2_unlink,
2170 	.mknod = gfs2_mknod,
2171 	.rename = gfs2_rename2,
2172 	.permission = gfs2_permission,
2173 	.setattr = gfs2_setattr,
2174 	.getattr = gfs2_getattr,
2175 	.listxattr = gfs2_listxattr,
2176 	.fiemap = gfs2_fiemap,
2177 	.get_acl = gfs2_get_acl,
2178 	.set_acl = gfs2_set_acl,
2179 	.update_time = gfs2_update_time,
2180 	.atomic_open = gfs2_atomic_open,
2181 	.fileattr_get = gfs2_fileattr_get,
2182 	.fileattr_set = gfs2_fileattr_set,
2183 };
2184 
2185 static const struct inode_operations gfs2_symlink_iops = {
2186 	.get_link = gfs2_get_link,
2187 	.permission = gfs2_permission,
2188 	.setattr = gfs2_setattr,
2189 	.getattr = gfs2_getattr,
2190 	.listxattr = gfs2_listxattr,
2191 	.fiemap = gfs2_fiemap,
2192 };
2193 
2194