xref: /linux/fs/xfs/xfs_iops.c (revision 364eeb79a213fcf9164208b53764223ad522d6b3)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
4  * All Rights Reserved.
5  */
6 #include "xfs.h"
7 #include "xfs_fs.h"
8 #include "xfs_shared.h"
9 #include "xfs_format.h"
10 #include "xfs_log_format.h"
11 #include "xfs_trans_resv.h"
12 #include "xfs_mount.h"
13 #include "xfs_inode.h"
14 #include "xfs_acl.h"
15 #include "xfs_quota.h"
16 #include "xfs_da_format.h"
17 #include "xfs_da_btree.h"
18 #include "xfs_attr.h"
19 #include "xfs_trans.h"
20 #include "xfs_trans_space.h"
21 #include "xfs_bmap_btree.h"
22 #include "xfs_trace.h"
23 #include "xfs_icache.h"
24 #include "xfs_symlink.h"
25 #include "xfs_dir2.h"
26 #include "xfs_iomap.h"
27 #include "xfs_error.h"
28 #include "xfs_ioctl.h"
29 #include "xfs_xattr.h"
30 #include "xfs_file.h"
31 #include "xfs_bmap.h"
32 
33 #include <linux/posix_acl.h>
34 #include <linux/security.h>
35 #include <linux/iversion.h>
36 #include <linux/fiemap.h>
37 
38 /*
39  * Directories have different lock order w.r.t. mmap_lock compared to regular
40  * files. This is due to readdir potentially triggering page faults on a user
41  * buffer inside filldir(), and this happens with the ilock on the directory
42  * held. For regular files, the lock order is the other way around - the
43  * mmap_lock is taken during the page fault, and then we lock the ilock to do
44  * block mapping. Hence we need a different class for the directory ilock so
45  * that lockdep can tell them apart.
46  */
47 static struct lock_class_key xfs_nondir_ilock_class;
48 static struct lock_class_key xfs_dir_ilock_class;
49 
50 static int
51 xfs_initxattrs(
52 	struct inode		*inode,
53 	const struct xattr	*xattr_array,
54 	void			*fs_info)
55 {
56 	const struct xattr	*xattr;
57 	struct xfs_inode	*ip = XFS_I(inode);
58 	int			error = 0;
59 
60 	for (xattr = xattr_array; xattr->name != NULL; xattr++) {
61 		struct xfs_da_args	args = {
62 			.dp		= ip,
63 			.attr_filter	= XFS_ATTR_SECURE,
64 			.name		= xattr->name,
65 			.namelen	= strlen(xattr->name),
66 			.value		= xattr->value,
67 			.valuelen	= xattr->value_len,
68 		};
69 		error = xfs_attr_change(&args, XFS_ATTRUPDATE_UPSERT);
70 		if (error < 0)
71 			break;
72 	}
73 	return error;
74 }
75 
76 /*
77  * Hook in SELinux.  This is not quite correct yet, what we really need
78  * here (as we do for default ACLs) is a mechanism by which creation of
79  * these attrs can be journalled at inode creation time (along with the
80  * inode, of course, such that log replay can't cause these to be lost).
81  */
82 int
83 xfs_inode_init_security(
84 	struct inode	*inode,
85 	struct inode	*dir,
86 	const struct qstr *qstr)
87 {
88 	return security_inode_init_security(inode, dir, qstr,
89 					     &xfs_initxattrs, NULL);
90 }
91 
92 static void
93 xfs_dentry_to_name(
94 	struct xfs_name	*namep,
95 	struct dentry	*dentry)
96 {
97 	namep->name = dentry->d_name.name;
98 	namep->len = dentry->d_name.len;
99 	namep->type = XFS_DIR3_FT_UNKNOWN;
100 }
101 
102 static int
103 xfs_dentry_mode_to_name(
104 	struct xfs_name	*namep,
105 	struct dentry	*dentry,
106 	int		mode)
107 {
108 	namep->name = dentry->d_name.name;
109 	namep->len = dentry->d_name.len;
110 	namep->type = xfs_mode_to_ftype(mode);
111 
112 	if (unlikely(namep->type == XFS_DIR3_FT_UNKNOWN))
113 		return -EFSCORRUPTED;
114 
115 	return 0;
116 }
117 
118 STATIC void
119 xfs_cleanup_inode(
120 	struct inode	*dir,
121 	struct inode	*inode,
122 	struct dentry	*dentry)
123 {
124 	struct xfs_name	teardown;
125 
126 	/* Oh, the horror.
127 	 * If we can't add the ACL or we fail in
128 	 * xfs_inode_init_security we must back out.
129 	 * ENOSPC can hit here, among other things.
130 	 */
131 	xfs_dentry_to_name(&teardown, dentry);
132 
133 	xfs_remove(XFS_I(dir), &teardown, XFS_I(inode));
134 }
135 
136 /*
137  * Check to see if we are likely to need an extended attribute to be added to
138  * the inode we are about to allocate. This allows the attribute fork to be
139  * created during the inode allocation, reducing the number of transactions we
140  * need to do in this fast path.
141  *
142  * The security checks are optimistic, but not guaranteed. The two LSMs that
143  * require xattrs to be added here (selinux and smack) are also the only two
144  * LSMs that add a sb->s_security structure to the superblock. Hence if security
145  * is enabled and sb->s_security is set, we have a pretty good idea that we are
146  * going to be asked to add a security xattr immediately after allocating the
147  * xfs inode and instantiating the VFS inode.
148  */
149 static inline bool
150 xfs_create_need_xattr(
151 	struct inode	*dir,
152 	struct posix_acl *default_acl,
153 	struct posix_acl *acl)
154 {
155 	if (acl)
156 		return true;
157 	if (default_acl)
158 		return true;
159 #if IS_ENABLED(CONFIG_SECURITY)
160 	if (dir->i_sb->s_security)
161 		return true;
162 #endif
163 	return false;
164 }
165 
166 
167 STATIC int
168 xfs_generic_create(
169 	struct mnt_idmap	*idmap,
170 	struct inode		*dir,
171 	struct dentry		*dentry,
172 	umode_t			mode,
173 	dev_t			rdev,
174 	struct file		*tmpfile)	/* unnamed file */
175 {
176 	struct xfs_icreate_args	args = {
177 		.idmap		= idmap,
178 		.pip		= XFS_I(dir),
179 		.rdev		= rdev,
180 		.mode		= mode,
181 	};
182 	struct inode		*inode;
183 	struct xfs_inode	*ip = NULL;
184 	struct posix_acl	*default_acl, *acl;
185 	struct xfs_name		name;
186 	int			error;
187 
188 	/*
189 	 * Irix uses Missed'em'V split, but doesn't want to see
190 	 * the upper 5 bits of (14bit) major.
191 	 */
192 	if (S_ISCHR(args.mode) || S_ISBLK(args.mode)) {
193 		if (unlikely(!sysv_valid_dev(args.rdev) ||
194 			     MAJOR(args.rdev) & ~0x1ff))
195 			return -EINVAL;
196 	} else {
197 		args.rdev = 0;
198 	}
199 
200 	error = posix_acl_create(dir, &args.mode, &default_acl, &acl);
201 	if (error)
202 		return error;
203 
204 	/* Verify mode is valid also for tmpfile case */
205 	error = xfs_dentry_mode_to_name(&name, dentry, args.mode);
206 	if (unlikely(error))
207 		goto out_free_acl;
208 
209 	if (!tmpfile) {
210 		if (xfs_create_need_xattr(dir, default_acl, acl))
211 			args.flags |= XFS_ICREATE_INIT_XATTRS;
212 
213 		error = xfs_create(&args, &name, &ip);
214 	} else {
215 		args.flags |= XFS_ICREATE_TMPFILE;
216 
217 		/*
218 		 * If this temporary file will not be linkable, don't bother
219 		 * creating an attr fork to receive a parent pointer.
220 		 */
221 		if (tmpfile->f_flags & O_EXCL)
222 			args.flags |= XFS_ICREATE_UNLINKABLE;
223 
224 		error = xfs_create_tmpfile(&args, &ip);
225 	}
226 	if (unlikely(error))
227 		goto out_free_acl;
228 
229 	inode = VFS_I(ip);
230 
231 	error = xfs_inode_init_security(inode, dir, &dentry->d_name);
232 	if (unlikely(error))
233 		goto out_cleanup_inode;
234 
235 	if (default_acl) {
236 		error = __xfs_set_acl(inode, default_acl, ACL_TYPE_DEFAULT);
237 		if (error)
238 			goto out_cleanup_inode;
239 	}
240 	if (acl) {
241 		error = __xfs_set_acl(inode, acl, ACL_TYPE_ACCESS);
242 		if (error)
243 			goto out_cleanup_inode;
244 	}
245 
246 	xfs_setup_iops(ip);
247 
248 	if (tmpfile) {
249 		/*
250 		 * The VFS requires that any inode fed to d_tmpfile must have
251 		 * nlink == 1 so that it can decrement the nlink in d_tmpfile.
252 		 * However, we created the temp file with nlink == 0 because
253 		 * we're not allowed to put an inode with nlink > 0 on the
254 		 * unlinked list.  Therefore we have to set nlink to 1 so that
255 		 * d_tmpfile can immediately set it back to zero.
256 		 */
257 		set_nlink(inode, 1);
258 		d_tmpfile(tmpfile, inode);
259 	} else
260 		d_instantiate(dentry, inode);
261 
262 	xfs_finish_inode_setup(ip);
263 
264  out_free_acl:
265 	posix_acl_release(default_acl);
266 	posix_acl_release(acl);
267 	return error;
268 
269  out_cleanup_inode:
270 	xfs_finish_inode_setup(ip);
271 	if (!tmpfile)
272 		xfs_cleanup_inode(dir, inode, dentry);
273 	xfs_irele(ip);
274 	goto out_free_acl;
275 }
276 
277 STATIC int
278 xfs_vn_mknod(
279 	struct mnt_idmap	*idmap,
280 	struct inode		*dir,
281 	struct dentry		*dentry,
282 	umode_t			mode,
283 	dev_t			rdev)
284 {
285 	return xfs_generic_create(idmap, dir, dentry, mode, rdev, NULL);
286 }
287 
288 STATIC int
289 xfs_vn_create(
290 	struct mnt_idmap	*idmap,
291 	struct inode		*dir,
292 	struct dentry		*dentry,
293 	umode_t			mode,
294 	bool			flags)
295 {
296 	return xfs_generic_create(idmap, dir, dentry, mode, 0, NULL);
297 }
298 
299 STATIC int
300 xfs_vn_mkdir(
301 	struct mnt_idmap	*idmap,
302 	struct inode		*dir,
303 	struct dentry		*dentry,
304 	umode_t			mode)
305 {
306 	return xfs_generic_create(idmap, dir, dentry, mode | S_IFDIR, 0, NULL);
307 }
308 
309 STATIC struct dentry *
310 xfs_vn_lookup(
311 	struct inode	*dir,
312 	struct dentry	*dentry,
313 	unsigned int flags)
314 {
315 	struct inode *inode;
316 	struct xfs_inode *cip;
317 	struct xfs_name	name;
318 	int		error;
319 
320 	if (dentry->d_name.len >= MAXNAMELEN)
321 		return ERR_PTR(-ENAMETOOLONG);
322 
323 	xfs_dentry_to_name(&name, dentry);
324 	error = xfs_lookup(XFS_I(dir), &name, &cip, NULL);
325 	if (likely(!error))
326 		inode = VFS_I(cip);
327 	else if (likely(error == -ENOENT))
328 		inode = NULL;
329 	else
330 		inode = ERR_PTR(error);
331 	return d_splice_alias(inode, dentry);
332 }
333 
334 STATIC struct dentry *
335 xfs_vn_ci_lookup(
336 	struct inode	*dir,
337 	struct dentry	*dentry,
338 	unsigned int flags)
339 {
340 	struct xfs_inode *ip;
341 	struct xfs_name	xname;
342 	struct xfs_name ci_name;
343 	struct qstr	dname;
344 	int		error;
345 
346 	if (dentry->d_name.len >= MAXNAMELEN)
347 		return ERR_PTR(-ENAMETOOLONG);
348 
349 	xfs_dentry_to_name(&xname, dentry);
350 	error = xfs_lookup(XFS_I(dir), &xname, &ip, &ci_name);
351 	if (unlikely(error)) {
352 		if (unlikely(error != -ENOENT))
353 			return ERR_PTR(error);
354 		/*
355 		 * call d_add(dentry, NULL) here when d_drop_negative_children
356 		 * is called in xfs_vn_mknod (ie. allow negative dentries
357 		 * with CI filesystems).
358 		 */
359 		return NULL;
360 	}
361 
362 	/* if exact match, just splice and exit */
363 	if (!ci_name.name)
364 		return d_splice_alias(VFS_I(ip), dentry);
365 
366 	/* else case-insensitive match... */
367 	dname.name = ci_name.name;
368 	dname.len = ci_name.len;
369 	dentry = d_add_ci(dentry, VFS_I(ip), &dname);
370 	kfree(ci_name.name);
371 	return dentry;
372 }
373 
374 STATIC int
375 xfs_vn_link(
376 	struct dentry	*old_dentry,
377 	struct inode	*dir,
378 	struct dentry	*dentry)
379 {
380 	struct inode	*inode = d_inode(old_dentry);
381 	struct xfs_name	name;
382 	int		error;
383 
384 	error = xfs_dentry_mode_to_name(&name, dentry, inode->i_mode);
385 	if (unlikely(error))
386 		return error;
387 
388 	if (IS_PRIVATE(inode))
389 		return -EPERM;
390 
391 	error = xfs_link(XFS_I(dir), XFS_I(inode), &name);
392 	if (unlikely(error))
393 		return error;
394 
395 	ihold(inode);
396 	d_instantiate(dentry, inode);
397 	return 0;
398 }
399 
400 STATIC int
401 xfs_vn_unlink(
402 	struct inode	*dir,
403 	struct dentry	*dentry)
404 {
405 	struct xfs_name	name;
406 	int		error;
407 
408 	xfs_dentry_to_name(&name, dentry);
409 
410 	error = xfs_remove(XFS_I(dir), &name, XFS_I(d_inode(dentry)));
411 	if (error)
412 		return error;
413 
414 	/*
415 	 * With unlink, the VFS makes the dentry "negative": no inode,
416 	 * but still hashed. This is incompatible with case-insensitive
417 	 * mode, so invalidate (unhash) the dentry in CI-mode.
418 	 */
419 	if (xfs_has_asciici(XFS_M(dir->i_sb)))
420 		d_invalidate(dentry);
421 	return 0;
422 }
423 
424 STATIC int
425 xfs_vn_symlink(
426 	struct mnt_idmap	*idmap,
427 	struct inode		*dir,
428 	struct dentry		*dentry,
429 	const char		*symname)
430 {
431 	struct inode	*inode;
432 	struct xfs_inode *cip = NULL;
433 	struct xfs_name	name;
434 	int		error;
435 	umode_t		mode;
436 
437 	mode = S_IFLNK |
438 		(irix_symlink_mode ? 0777 & ~current_umask() : S_IRWXUGO);
439 	error = xfs_dentry_mode_to_name(&name, dentry, mode);
440 	if (unlikely(error))
441 		goto out;
442 
443 	error = xfs_symlink(idmap, XFS_I(dir), &name, symname, mode, &cip);
444 	if (unlikely(error))
445 		goto out;
446 
447 	inode = VFS_I(cip);
448 
449 	error = xfs_inode_init_security(inode, dir, &dentry->d_name);
450 	if (unlikely(error))
451 		goto out_cleanup_inode;
452 
453 	xfs_setup_iops(cip);
454 
455 	d_instantiate(dentry, inode);
456 	xfs_finish_inode_setup(cip);
457 	return 0;
458 
459  out_cleanup_inode:
460 	xfs_finish_inode_setup(cip);
461 	xfs_cleanup_inode(dir, inode, dentry);
462 	xfs_irele(cip);
463  out:
464 	return error;
465 }
466 
467 STATIC int
468 xfs_vn_rename(
469 	struct mnt_idmap	*idmap,
470 	struct inode		*odir,
471 	struct dentry		*odentry,
472 	struct inode		*ndir,
473 	struct dentry		*ndentry,
474 	unsigned int		flags)
475 {
476 	struct inode	*new_inode = d_inode(ndentry);
477 	int		omode = 0;
478 	int		error;
479 	struct xfs_name	oname;
480 	struct xfs_name	nname;
481 
482 	if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))
483 		return -EINVAL;
484 
485 	/* if we are exchanging files, we need to set i_mode of both files */
486 	if (flags & RENAME_EXCHANGE)
487 		omode = d_inode(ndentry)->i_mode;
488 
489 	error = xfs_dentry_mode_to_name(&oname, odentry, omode);
490 	if (omode && unlikely(error))
491 		return error;
492 
493 	error = xfs_dentry_mode_to_name(&nname, ndentry,
494 					d_inode(odentry)->i_mode);
495 	if (unlikely(error))
496 		return error;
497 
498 	return xfs_rename(idmap, XFS_I(odir), &oname,
499 			  XFS_I(d_inode(odentry)), XFS_I(ndir), &nname,
500 			  new_inode ? XFS_I(new_inode) : NULL, flags);
501 }
502 
503 /*
504  * careful here - this function can get called recursively, so
505  * we need to be very careful about how much stack we use.
506  * uio is kmalloced for this reason...
507  */
508 STATIC const char *
509 xfs_vn_get_link(
510 	struct dentry		*dentry,
511 	struct inode		*inode,
512 	struct delayed_call	*done)
513 {
514 	char			*link;
515 	int			error = -ENOMEM;
516 
517 	if (!dentry)
518 		return ERR_PTR(-ECHILD);
519 
520 	link = kmalloc(XFS_SYMLINK_MAXLEN+1, GFP_KERNEL);
521 	if (!link)
522 		goto out_err;
523 
524 	error = xfs_readlink(XFS_I(d_inode(dentry)), link);
525 	if (unlikely(error))
526 		goto out_kfree;
527 
528 	set_delayed_call(done, kfree_link, link);
529 	return link;
530 
531  out_kfree:
532 	kfree(link);
533  out_err:
534 	return ERR_PTR(error);
535 }
536 
537 static uint32_t
538 xfs_stat_blksize(
539 	struct xfs_inode	*ip)
540 {
541 	struct xfs_mount	*mp = ip->i_mount;
542 
543 	/*
544 	 * If the file blocks are being allocated from a realtime volume, then
545 	 * always return the realtime extent size.
546 	 */
547 	if (XFS_IS_REALTIME_INODE(ip))
548 		return XFS_FSB_TO_B(mp, xfs_get_extsz_hint(ip) ? : 1);
549 
550 	/*
551 	 * Allow large block sizes to be reported to userspace programs if the
552 	 * "largeio" mount option is used.
553 	 *
554 	 * If compatibility mode is specified, simply return the basic unit of
555 	 * caching so that we don't get inefficient read/modify/write I/O from
556 	 * user apps. Otherwise....
557 	 *
558 	 * If the underlying volume is a stripe, then return the stripe width in
559 	 * bytes as the recommended I/O size. It is not a stripe and we've set a
560 	 * default buffered I/O size, return that, otherwise return the compat
561 	 * default.
562 	 */
563 	if (xfs_has_large_iosize(mp)) {
564 		if (mp->m_swidth)
565 			return XFS_FSB_TO_B(mp, mp->m_swidth);
566 		if (xfs_has_allocsize(mp))
567 			return 1U << mp->m_allocsize_log;
568 	}
569 
570 	return max_t(uint32_t, PAGE_SIZE, mp->m_sb.sb_blocksize);
571 }
572 
573 static void
574 xfs_get_atomic_write_attr(
575 	struct xfs_inode	*ip,
576 	unsigned int		*unit_min,
577 	unsigned int		*unit_max)
578 {
579 	if (!xfs_inode_can_atomicwrite(ip)) {
580 		*unit_min = *unit_max = 0;
581 		return;
582 	}
583 
584 	*unit_min = *unit_max = ip->i_mount->m_sb.sb_blocksize;
585 }
586 
587 STATIC int
588 xfs_vn_getattr(
589 	struct mnt_idmap	*idmap,
590 	const struct path	*path,
591 	struct kstat		*stat,
592 	u32			request_mask,
593 	unsigned int		query_flags)
594 {
595 	struct inode		*inode = d_inode(path->dentry);
596 	struct xfs_inode	*ip = XFS_I(inode);
597 	struct xfs_mount	*mp = ip->i_mount;
598 	vfsuid_t		vfsuid = i_uid_into_vfsuid(idmap, inode);
599 	vfsgid_t		vfsgid = i_gid_into_vfsgid(idmap, inode);
600 
601 	trace_xfs_getattr(ip);
602 
603 	if (xfs_is_shutdown(mp))
604 		return -EIO;
605 
606 	stat->size = XFS_ISIZE(ip);
607 	stat->dev = inode->i_sb->s_dev;
608 	stat->mode = inode->i_mode;
609 	stat->nlink = inode->i_nlink;
610 	stat->uid = vfsuid_into_kuid(vfsuid);
611 	stat->gid = vfsgid_into_kgid(vfsgid);
612 	stat->ino = ip->i_ino;
613 	stat->atime = inode_get_atime(inode);
614 
615 	fill_mg_cmtime(stat, request_mask, inode);
616 
617 	stat->blocks = XFS_FSB_TO_BB(mp, ip->i_nblocks + ip->i_delayed_blks);
618 
619 	if (xfs_has_v3inodes(mp)) {
620 		if (request_mask & STATX_BTIME) {
621 			stat->result_mask |= STATX_BTIME;
622 			stat->btime = ip->i_crtime;
623 		}
624 	}
625 
626 	/*
627 	 * Note: If you add another clause to set an attribute flag, please
628 	 * update attributes_mask below.
629 	 */
630 	if (ip->i_diflags & XFS_DIFLAG_IMMUTABLE)
631 		stat->attributes |= STATX_ATTR_IMMUTABLE;
632 	if (ip->i_diflags & XFS_DIFLAG_APPEND)
633 		stat->attributes |= STATX_ATTR_APPEND;
634 	if (ip->i_diflags & XFS_DIFLAG_NODUMP)
635 		stat->attributes |= STATX_ATTR_NODUMP;
636 
637 	stat->attributes_mask |= (STATX_ATTR_IMMUTABLE |
638 				  STATX_ATTR_APPEND |
639 				  STATX_ATTR_NODUMP);
640 
641 	switch (inode->i_mode & S_IFMT) {
642 	case S_IFBLK:
643 	case S_IFCHR:
644 		stat->blksize = BLKDEV_IOSIZE;
645 		stat->rdev = inode->i_rdev;
646 		break;
647 	case S_IFREG:
648 		if (request_mask & STATX_DIOALIGN) {
649 			struct xfs_buftarg	*target = xfs_inode_buftarg(ip);
650 			struct block_device	*bdev = target->bt_bdev;
651 
652 			stat->result_mask |= STATX_DIOALIGN;
653 			stat->dio_mem_align = bdev_dma_alignment(bdev) + 1;
654 			stat->dio_offset_align = bdev_logical_block_size(bdev);
655 		}
656 		if (request_mask & STATX_WRITE_ATOMIC) {
657 			unsigned int	unit_min, unit_max;
658 
659 			xfs_get_atomic_write_attr(ip, &unit_min,
660 					&unit_max);
661 			generic_fill_statx_atomic_writes(stat,
662 					unit_min, unit_max);
663 		}
664 		fallthrough;
665 	default:
666 		stat->blksize = xfs_stat_blksize(ip);
667 		stat->rdev = 0;
668 		break;
669 	}
670 
671 	return 0;
672 }
673 
674 static int
675 xfs_vn_change_ok(
676 	struct mnt_idmap	*idmap,
677 	struct dentry		*dentry,
678 	struct iattr		*iattr)
679 {
680 	struct xfs_mount	*mp = XFS_I(d_inode(dentry))->i_mount;
681 
682 	if (xfs_is_readonly(mp))
683 		return -EROFS;
684 
685 	if (xfs_is_shutdown(mp))
686 		return -EIO;
687 
688 	return setattr_prepare(idmap, dentry, iattr);
689 }
690 
691 /*
692  * Set non-size attributes of an inode.
693  *
694  * Caution: The caller of this function is responsible for calling
695  * setattr_prepare() or otherwise verifying the change is fine.
696  */
697 static int
698 xfs_setattr_nonsize(
699 	struct mnt_idmap	*idmap,
700 	struct dentry		*dentry,
701 	struct xfs_inode	*ip,
702 	struct iattr		*iattr)
703 {
704 	xfs_mount_t		*mp = ip->i_mount;
705 	struct inode		*inode = VFS_I(ip);
706 	int			mask = iattr->ia_valid;
707 	xfs_trans_t		*tp;
708 	int			error;
709 	kuid_t			uid = GLOBAL_ROOT_UID;
710 	kgid_t			gid = GLOBAL_ROOT_GID;
711 	struct xfs_dquot	*udqp = NULL, *gdqp = NULL;
712 	struct xfs_dquot	*old_udqp = NULL, *old_gdqp = NULL;
713 
714 	ASSERT((mask & ATTR_SIZE) == 0);
715 
716 	/*
717 	 * If disk quotas is on, we make sure that the dquots do exist on disk,
718 	 * before we start any other transactions. Trying to do this later
719 	 * is messy. We don't care to take a readlock to look at the ids
720 	 * in inode here, because we can't hold it across the trans_reserve.
721 	 * If the IDs do change before we take the ilock, we're covered
722 	 * because the i_*dquot fields will get updated anyway.
723 	 */
724 	if (XFS_IS_QUOTA_ON(mp) && (mask & (ATTR_UID|ATTR_GID))) {
725 		uint	qflags = 0;
726 
727 		if ((mask & ATTR_UID) && XFS_IS_UQUOTA_ON(mp)) {
728 			uid = from_vfsuid(idmap, i_user_ns(inode),
729 					  iattr->ia_vfsuid);
730 			qflags |= XFS_QMOPT_UQUOTA;
731 		} else {
732 			uid = inode->i_uid;
733 		}
734 		if ((mask & ATTR_GID) && XFS_IS_GQUOTA_ON(mp)) {
735 			gid = from_vfsgid(idmap, i_user_ns(inode),
736 					  iattr->ia_vfsgid);
737 			qflags |= XFS_QMOPT_GQUOTA;
738 		}  else {
739 			gid = inode->i_gid;
740 		}
741 
742 		/*
743 		 * We take a reference when we initialize udqp and gdqp,
744 		 * so it is important that we never blindly double trip on
745 		 * the same variable. See xfs_create() for an example.
746 		 */
747 		ASSERT(udqp == NULL);
748 		ASSERT(gdqp == NULL);
749 		error = xfs_qm_vop_dqalloc(ip, uid, gid, ip->i_projid,
750 					   qflags, &udqp, &gdqp, NULL);
751 		if (error)
752 			return error;
753 	}
754 
755 	error = xfs_trans_alloc_ichange(ip, udqp, gdqp, NULL,
756 			has_capability_noaudit(current, CAP_FOWNER), &tp);
757 	if (error)
758 		goto out_dqrele;
759 
760 	/*
761 	 * Register quota modifications in the transaction.  Must be the owner
762 	 * or privileged.  These IDs could have changed since we last looked at
763 	 * them.  But, we're assured that if the ownership did change while we
764 	 * didn't have the inode locked, inode's dquot(s) would have changed
765 	 * also.
766 	 */
767 	if (XFS_IS_UQUOTA_ON(mp) &&
768 	    i_uid_needs_update(idmap, iattr, inode)) {
769 		ASSERT(udqp);
770 		old_udqp = xfs_qm_vop_chown(tp, ip, &ip->i_udquot, udqp);
771 	}
772 	if (XFS_IS_GQUOTA_ON(mp) &&
773 	    i_gid_needs_update(idmap, iattr, inode)) {
774 		ASSERT(xfs_has_pquotino(mp) || !XFS_IS_PQUOTA_ON(mp));
775 		ASSERT(gdqp);
776 		old_gdqp = xfs_qm_vop_chown(tp, ip, &ip->i_gdquot, gdqp);
777 	}
778 
779 	setattr_copy(idmap, inode, iattr);
780 	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
781 
782 	XFS_STATS_INC(mp, xs_ig_attrchg);
783 
784 	if (xfs_has_wsync(mp))
785 		xfs_trans_set_sync(tp);
786 	error = xfs_trans_commit(tp);
787 
788 	/*
789 	 * Release any dquot(s) the inode had kept before chown.
790 	 */
791 	xfs_qm_dqrele(old_udqp);
792 	xfs_qm_dqrele(old_gdqp);
793 	xfs_qm_dqrele(udqp);
794 	xfs_qm_dqrele(gdqp);
795 
796 	if (error)
797 		return error;
798 
799 	/*
800 	 * XXX(hch): Updating the ACL entries is not atomic vs the i_mode
801 	 * 	     update.  We could avoid this with linked transactions
802 	 * 	     and passing down the transaction pointer all the way
803 	 *	     to attr_set.  No previous user of the generic
804 	 * 	     Posix ACL code seems to care about this issue either.
805 	 */
806 	if (mask & ATTR_MODE) {
807 		error = posix_acl_chmod(idmap, dentry, inode->i_mode);
808 		if (error)
809 			return error;
810 	}
811 
812 	return 0;
813 
814 out_dqrele:
815 	xfs_qm_dqrele(udqp);
816 	xfs_qm_dqrele(gdqp);
817 	return error;
818 }
819 
820 /*
821  * Truncate file.  Must have write permission and not be a directory.
822  *
823  * Caution: The caller of this function is responsible for calling
824  * setattr_prepare() or otherwise verifying the change is fine.
825  */
826 STATIC int
827 xfs_setattr_size(
828 	struct mnt_idmap	*idmap,
829 	struct dentry		*dentry,
830 	struct xfs_inode	*ip,
831 	struct iattr		*iattr)
832 {
833 	struct xfs_mount	*mp = ip->i_mount;
834 	struct inode		*inode = VFS_I(ip);
835 	xfs_off_t		oldsize, newsize;
836 	struct xfs_trans	*tp;
837 	int			error;
838 	uint			lock_flags = 0;
839 	uint			resblks = 0;
840 	bool			did_zeroing = false;
841 
842 	xfs_assert_ilocked(ip, XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL);
843 	ASSERT(S_ISREG(inode->i_mode));
844 	ASSERT((iattr->ia_valid & (ATTR_UID|ATTR_GID|ATTR_ATIME|ATTR_ATIME_SET|
845 		ATTR_MTIME_SET|ATTR_TIMES_SET)) == 0);
846 
847 	oldsize = inode->i_size;
848 	newsize = iattr->ia_size;
849 
850 	/*
851 	 * Short circuit the truncate case for zero length files.
852 	 */
853 	if (newsize == 0 && oldsize == 0 && ip->i_df.if_nextents == 0) {
854 		if (!(iattr->ia_valid & (ATTR_CTIME|ATTR_MTIME)))
855 			return 0;
856 
857 		/*
858 		 * Use the regular setattr path to update the timestamps.
859 		 */
860 		iattr->ia_valid &= ~ATTR_SIZE;
861 		return xfs_setattr_nonsize(idmap, dentry, ip, iattr);
862 	}
863 
864 	/*
865 	 * Make sure that the dquots are attached to the inode.
866 	 */
867 	error = xfs_qm_dqattach(ip);
868 	if (error)
869 		return error;
870 
871 	/*
872 	 * Wait for all direct I/O to complete.
873 	 */
874 	inode_dio_wait(inode);
875 
876 	/*
877 	 * File data changes must be complete before we start the transaction to
878 	 * modify the inode.  This needs to be done before joining the inode to
879 	 * the transaction because the inode cannot be unlocked once it is a
880 	 * part of the transaction.
881 	 *
882 	 * Start with zeroing any data beyond EOF that we may expose on file
883 	 * extension, or zeroing out the rest of the block on a downward
884 	 * truncate.
885 	 */
886 	if (newsize > oldsize) {
887 		trace_xfs_zero_eof(ip, oldsize, newsize - oldsize);
888 		error = xfs_zero_range(ip, oldsize, newsize - oldsize,
889 				&did_zeroing);
890 	} else {
891 		error = xfs_truncate_page(ip, newsize, &did_zeroing);
892 	}
893 
894 	if (error)
895 		return error;
896 
897 	/*
898 	 * We've already locked out new page faults, so now we can safely remove
899 	 * pages from the page cache knowing they won't get refaulted until we
900 	 * drop the XFS_MMAP_EXCL lock after the extent manipulations are
901 	 * complete. The truncate_setsize() call also cleans partial EOF page
902 	 * PTEs on extending truncates and hence ensures sub-page block size
903 	 * filesystems are correctly handled, too.
904 	 *
905 	 * We have to do all the page cache truncate work outside the
906 	 * transaction context as the "lock" order is page lock->log space
907 	 * reservation as defined by extent allocation in the writeback path.
908 	 * Hence a truncate can fail with ENOMEM from xfs_trans_alloc(), but
909 	 * having already truncated the in-memory version of the file (i.e. made
910 	 * user visible changes). There's not much we can do about this, except
911 	 * to hope that the caller sees ENOMEM and retries the truncate
912 	 * operation.
913 	 *
914 	 * And we update in-core i_size and truncate page cache beyond newsize
915 	 * before writeback the [i_disk_size, newsize] range, so we're
916 	 * guaranteed not to write stale data past the new EOF on truncate down.
917 	 */
918 	truncate_setsize(inode, newsize);
919 
920 	/*
921 	 * We are going to log the inode size change in this transaction so
922 	 * any previous writes that are beyond the on disk EOF and the new
923 	 * EOF that have not been written out need to be written here.  If we
924 	 * do not write the data out, we expose ourselves to the null files
925 	 * problem. Note that this includes any block zeroing we did above;
926 	 * otherwise those blocks may not be zeroed after a crash.
927 	 */
928 	if (did_zeroing ||
929 	    (newsize > ip->i_disk_size && oldsize != ip->i_disk_size)) {
930 		error = filemap_write_and_wait_range(VFS_I(ip)->i_mapping,
931 						ip->i_disk_size, newsize - 1);
932 		if (error)
933 			return error;
934 	}
935 
936 	/*
937 	 * For realtime inode with more than one block rtextsize, we need the
938 	 * block reservation for bmap btree block allocations/splits that can
939 	 * happen since it could split the tail written extent and convert the
940 	 * right beyond EOF one to unwritten.
941 	 */
942 	if (xfs_inode_has_bigrtalloc(ip))
943 		resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
944 
945 	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, resblks,
946 				0, 0, &tp);
947 	if (error)
948 		return error;
949 
950 	lock_flags |= XFS_ILOCK_EXCL;
951 	xfs_ilock(ip, XFS_ILOCK_EXCL);
952 	xfs_trans_ijoin(tp, ip, 0);
953 
954 	/*
955 	 * Only change the c/mtime if we are changing the size or we are
956 	 * explicitly asked to change it.  This handles the semantic difference
957 	 * between truncate() and ftruncate() as implemented in the VFS.
958 	 *
959 	 * The regular truncate() case without ATTR_CTIME and ATTR_MTIME is a
960 	 * special case where we need to update the times despite not having
961 	 * these flags set.  For all other operations the VFS set these flags
962 	 * explicitly if it wants a timestamp update.
963 	 */
964 	if (newsize != oldsize &&
965 	    !(iattr->ia_valid & (ATTR_CTIME | ATTR_MTIME))) {
966 		iattr->ia_ctime = iattr->ia_mtime =
967 			current_time(inode);
968 		iattr->ia_valid |= ATTR_CTIME | ATTR_MTIME;
969 	}
970 
971 	/*
972 	 * The first thing we do is set the size to new_size permanently on
973 	 * disk.  This way we don't have to worry about anyone ever being able
974 	 * to look at the data being freed even in the face of a crash.
975 	 * What we're getting around here is the case where we free a block, it
976 	 * is allocated to another file, it is written to, and then we crash.
977 	 * If the new data gets written to the file but the log buffers
978 	 * containing the free and reallocation don't, then we'd end up with
979 	 * garbage in the blocks being freed.  As long as we make the new size
980 	 * permanent before actually freeing any blocks it doesn't matter if
981 	 * they get written to.
982 	 */
983 	ip->i_disk_size = newsize;
984 	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
985 
986 	if (newsize <= oldsize) {
987 		error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, newsize);
988 		if (error)
989 			goto out_trans_cancel;
990 
991 		/*
992 		 * Truncated "down", so we're removing references to old data
993 		 * here - if we delay flushing for a long time, we expose
994 		 * ourselves unduly to the notorious NULL files problem.  So,
995 		 * we mark this inode and flush it when the file is closed,
996 		 * and do not wait the usual (long) time for writeout.
997 		 */
998 		xfs_iflags_set(ip, XFS_ITRUNCATED);
999 
1000 		/* A truncate down always removes post-EOF blocks. */
1001 		xfs_inode_clear_eofblocks_tag(ip);
1002 	}
1003 
1004 	ASSERT(!(iattr->ia_valid & (ATTR_UID | ATTR_GID)));
1005 	setattr_copy(idmap, inode, iattr);
1006 	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1007 
1008 	XFS_STATS_INC(mp, xs_ig_attrchg);
1009 
1010 	if (xfs_has_wsync(mp))
1011 		xfs_trans_set_sync(tp);
1012 
1013 	error = xfs_trans_commit(tp);
1014 out_unlock:
1015 	if (lock_flags)
1016 		xfs_iunlock(ip, lock_flags);
1017 	return error;
1018 
1019 out_trans_cancel:
1020 	xfs_trans_cancel(tp);
1021 	goto out_unlock;
1022 }
1023 
1024 int
1025 xfs_vn_setattr_size(
1026 	struct mnt_idmap	*idmap,
1027 	struct dentry		*dentry,
1028 	struct iattr		*iattr)
1029 {
1030 	struct xfs_inode	*ip = XFS_I(d_inode(dentry));
1031 	int error;
1032 
1033 	trace_xfs_setattr(ip);
1034 
1035 	error = xfs_vn_change_ok(idmap, dentry, iattr);
1036 	if (error)
1037 		return error;
1038 	return xfs_setattr_size(idmap, dentry, ip, iattr);
1039 }
1040 
1041 STATIC int
1042 xfs_vn_setattr(
1043 	struct mnt_idmap	*idmap,
1044 	struct dentry		*dentry,
1045 	struct iattr		*iattr)
1046 {
1047 	struct inode		*inode = d_inode(dentry);
1048 	struct xfs_inode	*ip = XFS_I(inode);
1049 	int			error;
1050 
1051 	if (iattr->ia_valid & ATTR_SIZE) {
1052 		uint			iolock;
1053 
1054 		xfs_ilock(ip, XFS_MMAPLOCK_EXCL);
1055 		iolock = XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL;
1056 
1057 		error = xfs_break_layouts(inode, &iolock, BREAK_UNMAP);
1058 		if (error) {
1059 			xfs_iunlock(ip, XFS_MMAPLOCK_EXCL);
1060 			return error;
1061 		}
1062 
1063 		error = xfs_vn_setattr_size(idmap, dentry, iattr);
1064 		xfs_iunlock(ip, XFS_MMAPLOCK_EXCL);
1065 	} else {
1066 		trace_xfs_setattr(ip);
1067 
1068 		error = xfs_vn_change_ok(idmap, dentry, iattr);
1069 		if (!error)
1070 			error = xfs_setattr_nonsize(idmap, dentry, ip, iattr);
1071 	}
1072 
1073 	return error;
1074 }
1075 
1076 STATIC int
1077 xfs_vn_update_time(
1078 	struct inode		*inode,
1079 	int			flags)
1080 {
1081 	struct xfs_inode	*ip = XFS_I(inode);
1082 	struct xfs_mount	*mp = ip->i_mount;
1083 	int			log_flags = XFS_ILOG_TIMESTAMP;
1084 	struct xfs_trans	*tp;
1085 	int			error;
1086 	struct timespec64	now;
1087 
1088 	trace_xfs_update_time(ip);
1089 
1090 	if (inode->i_sb->s_flags & SB_LAZYTIME) {
1091 		if (!((flags & S_VERSION) &&
1092 		      inode_maybe_inc_iversion(inode, false))) {
1093 			generic_update_time(inode, flags);
1094 			return 0;
1095 		}
1096 
1097 		/* Capture the iversion update that just occurred */
1098 		log_flags |= XFS_ILOG_CORE;
1099 	}
1100 
1101 	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_fsyncts, 0, 0, 0, &tp);
1102 	if (error)
1103 		return error;
1104 
1105 	xfs_ilock(ip, XFS_ILOCK_EXCL);
1106 	if (flags & (S_CTIME|S_MTIME))
1107 		now = inode_set_ctime_current(inode);
1108 	else
1109 		now = current_time(inode);
1110 
1111 	if (flags & S_MTIME)
1112 		inode_set_mtime_to_ts(inode, now);
1113 	if (flags & S_ATIME)
1114 		inode_set_atime_to_ts(inode, now);
1115 
1116 	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
1117 	xfs_trans_log_inode(tp, ip, log_flags);
1118 	return xfs_trans_commit(tp);
1119 }
1120 
1121 STATIC int
1122 xfs_vn_fiemap(
1123 	struct inode		*inode,
1124 	struct fiemap_extent_info *fieinfo,
1125 	u64			start,
1126 	u64			length)
1127 {
1128 	int			error;
1129 
1130 	xfs_ilock(XFS_I(inode), XFS_IOLOCK_SHARED);
1131 	if (fieinfo->fi_flags & FIEMAP_FLAG_XATTR) {
1132 		fieinfo->fi_flags &= ~FIEMAP_FLAG_XATTR;
1133 		error = iomap_fiemap(inode, fieinfo, start, length,
1134 				&xfs_xattr_iomap_ops);
1135 	} else {
1136 		error = iomap_fiemap(inode, fieinfo, start, length,
1137 				&xfs_read_iomap_ops);
1138 	}
1139 	xfs_iunlock(XFS_I(inode), XFS_IOLOCK_SHARED);
1140 
1141 	return error;
1142 }
1143 
1144 STATIC int
1145 xfs_vn_tmpfile(
1146 	struct mnt_idmap	*idmap,
1147 	struct inode		*dir,
1148 	struct file		*file,
1149 	umode_t			mode)
1150 {
1151 	int err = xfs_generic_create(idmap, dir, file->f_path.dentry, mode, 0, file);
1152 
1153 	return finish_open_simple(file, err);
1154 }
1155 
1156 static const struct inode_operations xfs_inode_operations = {
1157 	.get_inode_acl		= xfs_get_acl,
1158 	.set_acl		= xfs_set_acl,
1159 	.getattr		= xfs_vn_getattr,
1160 	.setattr		= xfs_vn_setattr,
1161 	.listxattr		= xfs_vn_listxattr,
1162 	.fiemap			= xfs_vn_fiemap,
1163 	.update_time		= xfs_vn_update_time,
1164 	.fileattr_get		= xfs_fileattr_get,
1165 	.fileattr_set		= xfs_fileattr_set,
1166 };
1167 
1168 static const struct inode_operations xfs_dir_inode_operations = {
1169 	.create			= xfs_vn_create,
1170 	.lookup			= xfs_vn_lookup,
1171 	.link			= xfs_vn_link,
1172 	.unlink			= xfs_vn_unlink,
1173 	.symlink		= xfs_vn_symlink,
1174 	.mkdir			= xfs_vn_mkdir,
1175 	/*
1176 	 * Yes, XFS uses the same method for rmdir and unlink.
1177 	 *
1178 	 * There are some subtile differences deeper in the code,
1179 	 * but we use S_ISDIR to check for those.
1180 	 */
1181 	.rmdir			= xfs_vn_unlink,
1182 	.mknod			= xfs_vn_mknod,
1183 	.rename			= xfs_vn_rename,
1184 	.get_inode_acl		= xfs_get_acl,
1185 	.set_acl		= xfs_set_acl,
1186 	.getattr		= xfs_vn_getattr,
1187 	.setattr		= xfs_vn_setattr,
1188 	.listxattr		= xfs_vn_listxattr,
1189 	.update_time		= xfs_vn_update_time,
1190 	.tmpfile		= xfs_vn_tmpfile,
1191 	.fileattr_get		= xfs_fileattr_get,
1192 	.fileattr_set		= xfs_fileattr_set,
1193 };
1194 
1195 static const struct inode_operations xfs_dir_ci_inode_operations = {
1196 	.create			= xfs_vn_create,
1197 	.lookup			= xfs_vn_ci_lookup,
1198 	.link			= xfs_vn_link,
1199 	.unlink			= xfs_vn_unlink,
1200 	.symlink		= xfs_vn_symlink,
1201 	.mkdir			= xfs_vn_mkdir,
1202 	/*
1203 	 * Yes, XFS uses the same method for rmdir and unlink.
1204 	 *
1205 	 * There are some subtile differences deeper in the code,
1206 	 * but we use S_ISDIR to check for those.
1207 	 */
1208 	.rmdir			= xfs_vn_unlink,
1209 	.mknod			= xfs_vn_mknod,
1210 	.rename			= xfs_vn_rename,
1211 	.get_inode_acl		= xfs_get_acl,
1212 	.set_acl		= xfs_set_acl,
1213 	.getattr		= xfs_vn_getattr,
1214 	.setattr		= xfs_vn_setattr,
1215 	.listxattr		= xfs_vn_listxattr,
1216 	.update_time		= xfs_vn_update_time,
1217 	.tmpfile		= xfs_vn_tmpfile,
1218 	.fileattr_get		= xfs_fileattr_get,
1219 	.fileattr_set		= xfs_fileattr_set,
1220 };
1221 
1222 static const struct inode_operations xfs_symlink_inode_operations = {
1223 	.get_link		= xfs_vn_get_link,
1224 	.getattr		= xfs_vn_getattr,
1225 	.setattr		= xfs_vn_setattr,
1226 	.listxattr		= xfs_vn_listxattr,
1227 	.update_time		= xfs_vn_update_time,
1228 };
1229 
1230 /* Figure out if this file actually supports DAX. */
1231 static bool
1232 xfs_inode_supports_dax(
1233 	struct xfs_inode	*ip)
1234 {
1235 	struct xfs_mount	*mp = ip->i_mount;
1236 
1237 	/* Only supported on regular files. */
1238 	if (!S_ISREG(VFS_I(ip)->i_mode))
1239 		return false;
1240 
1241 	/* Block size must match page size */
1242 	if (mp->m_sb.sb_blocksize != PAGE_SIZE)
1243 		return false;
1244 
1245 	/* Device has to support DAX too. */
1246 	return xfs_inode_buftarg(ip)->bt_daxdev != NULL;
1247 }
1248 
1249 static bool
1250 xfs_inode_should_enable_dax(
1251 	struct xfs_inode *ip)
1252 {
1253 	if (!IS_ENABLED(CONFIG_FS_DAX))
1254 		return false;
1255 	if (xfs_has_dax_never(ip->i_mount))
1256 		return false;
1257 	if (!xfs_inode_supports_dax(ip))
1258 		return false;
1259 	if (xfs_has_dax_always(ip->i_mount))
1260 		return true;
1261 	if (ip->i_diflags2 & XFS_DIFLAG2_DAX)
1262 		return true;
1263 	return false;
1264 }
1265 
1266 void
1267 xfs_diflags_to_iflags(
1268 	struct xfs_inode	*ip,
1269 	bool init)
1270 {
1271 	struct inode            *inode = VFS_I(ip);
1272 	unsigned int            xflags = xfs_ip2xflags(ip);
1273 	unsigned int            flags = 0;
1274 
1275 	ASSERT(!(IS_DAX(inode) && init));
1276 
1277 	if (xflags & FS_XFLAG_IMMUTABLE)
1278 		flags |= S_IMMUTABLE;
1279 	if (xflags & FS_XFLAG_APPEND)
1280 		flags |= S_APPEND;
1281 	if (xflags & FS_XFLAG_SYNC)
1282 		flags |= S_SYNC;
1283 	if (xflags & FS_XFLAG_NOATIME)
1284 		flags |= S_NOATIME;
1285 	if (init && xfs_inode_should_enable_dax(ip))
1286 		flags |= S_DAX;
1287 
1288 	/*
1289 	 * S_DAX can only be set during inode initialization and is never set by
1290 	 * the VFS, so we cannot mask off S_DAX in i_flags.
1291 	 */
1292 	inode->i_flags &= ~(S_IMMUTABLE | S_APPEND | S_SYNC | S_NOATIME);
1293 	inode->i_flags |= flags;
1294 }
1295 
1296 /*
1297  * Initialize the Linux inode.
1298  *
1299  * When reading existing inodes from disk this is called directly from xfs_iget,
1300  * when creating a new inode it is called from xfs_init_new_inode after setting
1301  * up the inode. These callers have different criteria for clearing XFS_INEW, so
1302  * leave it up to the caller to deal with unlocking the inode appropriately.
1303  */
1304 void
1305 xfs_setup_inode(
1306 	struct xfs_inode	*ip)
1307 {
1308 	struct inode		*inode = &ip->i_vnode;
1309 	gfp_t			gfp_mask;
1310 
1311 	inode->i_ino = ip->i_ino;
1312 	inode->i_state |= I_NEW;
1313 
1314 	inode_sb_list_add(inode);
1315 	/* make the inode look hashed for the writeback code */
1316 	inode_fake_hash(inode);
1317 
1318 	i_size_write(inode, ip->i_disk_size);
1319 	xfs_diflags_to_iflags(ip, true);
1320 
1321 	if (S_ISDIR(inode->i_mode)) {
1322 		/*
1323 		 * We set the i_rwsem class here to avoid potential races with
1324 		 * lockdep_annotate_inode_mutex_key() reinitialising the lock
1325 		 * after a filehandle lookup has already found the inode in
1326 		 * cache before it has been unlocked via unlock_new_inode().
1327 		 */
1328 		lockdep_set_class(&inode->i_rwsem,
1329 				  &inode->i_sb->s_type->i_mutex_dir_key);
1330 		lockdep_set_class(&ip->i_lock, &xfs_dir_ilock_class);
1331 	} else {
1332 		lockdep_set_class(&ip->i_lock, &xfs_nondir_ilock_class);
1333 	}
1334 
1335 	/*
1336 	 * Ensure all page cache allocations are done from GFP_NOFS context to
1337 	 * prevent direct reclaim recursion back into the filesystem and blowing
1338 	 * stacks or deadlocking.
1339 	 */
1340 	gfp_mask = mapping_gfp_mask(inode->i_mapping);
1341 	mapping_set_gfp_mask(inode->i_mapping, (gfp_mask & ~(__GFP_FS)));
1342 
1343 	/*
1344 	 * For real-time inodes update the stable write flags to that of the RT
1345 	 * device instead of the data device.
1346 	 */
1347 	if (S_ISREG(inode->i_mode) && XFS_IS_REALTIME_INODE(ip))
1348 		xfs_update_stable_writes(ip);
1349 
1350 	/*
1351 	 * If there is no attribute fork no ACL can exist on this inode,
1352 	 * and it can't have any file capabilities attached to it either.
1353 	 */
1354 	if (!xfs_inode_has_attr_fork(ip)) {
1355 		inode_has_no_xattr(inode);
1356 		cache_no_acl(inode);
1357 	}
1358 }
1359 
1360 void
1361 xfs_setup_iops(
1362 	struct xfs_inode	*ip)
1363 {
1364 	struct inode		*inode = &ip->i_vnode;
1365 
1366 	switch (inode->i_mode & S_IFMT) {
1367 	case S_IFREG:
1368 		inode->i_op = &xfs_inode_operations;
1369 		inode->i_fop = &xfs_file_operations;
1370 		if (IS_DAX(inode))
1371 			inode->i_mapping->a_ops = &xfs_dax_aops;
1372 		else
1373 			inode->i_mapping->a_ops = &xfs_address_space_operations;
1374 		break;
1375 	case S_IFDIR:
1376 		if (xfs_has_asciici(XFS_M(inode->i_sb)))
1377 			inode->i_op = &xfs_dir_ci_inode_operations;
1378 		else
1379 			inode->i_op = &xfs_dir_inode_operations;
1380 		inode->i_fop = &xfs_dir_file_operations;
1381 		break;
1382 	case S_IFLNK:
1383 		inode->i_op = &xfs_symlink_inode_operations;
1384 		break;
1385 	default:
1386 		inode->i_op = &xfs_inode_operations;
1387 		init_special_inode(inode, inode->i_mode, inode->i_rdev);
1388 		break;
1389 	}
1390 }
1391