xref: /openbmc/linux/fs/xfs/xfs_iops.c (revision 05955a70)
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_trace.h"
21 #include "xfs_icache.h"
22 #include "xfs_symlink.h"
23 #include "xfs_dir2.h"
24 #include "xfs_iomap.h"
25 #include "xfs_error.h"
26 #include "xfs_ioctl.h"
27 #include "xfs_xattr.h"
28 
29 #include <linux/posix_acl.h>
30 #include <linux/security.h>
31 #include <linux/iversion.h>
32 #include <linux/fiemap.h>
33 
34 /*
35  * Directories have different lock order w.r.t. mmap_lock compared to regular
36  * files. This is due to readdir potentially triggering page faults on a user
37  * buffer inside filldir(), and this happens with the ilock on the directory
38  * held. For regular files, the lock order is the other way around - the
39  * mmap_lock is taken during the page fault, and then we lock the ilock to do
40  * block mapping. Hence we need a different class for the directory ilock so
41  * that lockdep can tell them apart.
42  */
43 static struct lock_class_key xfs_nondir_ilock_class;
44 static struct lock_class_key xfs_dir_ilock_class;
45 
46 static int
xfs_initxattrs(struct inode * inode,const struct xattr * xattr_array,void * fs_info)47 xfs_initxattrs(
48 	struct inode		*inode,
49 	const struct xattr	*xattr_array,
50 	void			*fs_info)
51 {
52 	const struct xattr	*xattr;
53 	struct xfs_inode	*ip = XFS_I(inode);
54 	int			error = 0;
55 
56 	for (xattr = xattr_array; xattr->name != NULL; xattr++) {
57 		struct xfs_da_args	args = {
58 			.dp		= ip,
59 			.attr_filter	= XFS_ATTR_SECURE,
60 			.name		= xattr->name,
61 			.namelen	= strlen(xattr->name),
62 			.value		= xattr->value,
63 			.valuelen	= xattr->value_len,
64 		};
65 		error = xfs_attr_change(&args);
66 		if (error < 0)
67 			break;
68 	}
69 	return error;
70 }
71 
72 /*
73  * Hook in SELinux.  This is not quite correct yet, what we really need
74  * here (as we do for default ACLs) is a mechanism by which creation of
75  * these attrs can be journalled at inode creation time (along with the
76  * inode, of course, such that log replay can't cause these to be lost).
77  */
78 int
xfs_inode_init_security(struct inode * inode,struct inode * dir,const struct qstr * qstr)79 xfs_inode_init_security(
80 	struct inode	*inode,
81 	struct inode	*dir,
82 	const struct qstr *qstr)
83 {
84 	return security_inode_init_security(inode, dir, qstr,
85 					     &xfs_initxattrs, NULL);
86 }
87 
88 static void
xfs_dentry_to_name(struct xfs_name * namep,struct dentry * dentry)89 xfs_dentry_to_name(
90 	struct xfs_name	*namep,
91 	struct dentry	*dentry)
92 {
93 	namep->name = dentry->d_name.name;
94 	namep->len = dentry->d_name.len;
95 	namep->type = XFS_DIR3_FT_UNKNOWN;
96 }
97 
98 static int
xfs_dentry_mode_to_name(struct xfs_name * namep,struct dentry * dentry,int mode)99 xfs_dentry_mode_to_name(
100 	struct xfs_name	*namep,
101 	struct dentry	*dentry,
102 	int		mode)
103 {
104 	namep->name = dentry->d_name.name;
105 	namep->len = dentry->d_name.len;
106 	namep->type = xfs_mode_to_ftype(mode);
107 
108 	if (unlikely(namep->type == XFS_DIR3_FT_UNKNOWN))
109 		return -EFSCORRUPTED;
110 
111 	return 0;
112 }
113 
114 STATIC void
xfs_cleanup_inode(struct inode * dir,struct inode * inode,struct dentry * dentry)115 xfs_cleanup_inode(
116 	struct inode	*dir,
117 	struct inode	*inode,
118 	struct dentry	*dentry)
119 {
120 	struct xfs_name	teardown;
121 
122 	/* Oh, the horror.
123 	 * If we can't add the ACL or we fail in
124 	 * xfs_inode_init_security we must back out.
125 	 * ENOSPC can hit here, among other things.
126 	 */
127 	xfs_dentry_to_name(&teardown, dentry);
128 
129 	xfs_remove(XFS_I(dir), &teardown, XFS_I(inode));
130 }
131 
132 /*
133  * Check to see if we are likely to need an extended attribute to be added to
134  * the inode we are about to allocate. This allows the attribute fork to be
135  * created during the inode allocation, reducing the number of transactions we
136  * need to do in this fast path.
137  *
138  * The security checks are optimistic, but not guaranteed. The two LSMs that
139  * require xattrs to be added here (selinux and smack) are also the only two
140  * LSMs that add a sb->s_security structure to the superblock. Hence if security
141  * is enabled and sb->s_security is set, we have a pretty good idea that we are
142  * going to be asked to add a security xattr immediately after allocating the
143  * xfs inode and instantiating the VFS inode.
144  */
145 static inline bool
xfs_create_need_xattr(struct inode * dir,struct posix_acl * default_acl,struct posix_acl * acl)146 xfs_create_need_xattr(
147 	struct inode	*dir,
148 	struct posix_acl *default_acl,
149 	struct posix_acl *acl)
150 {
151 	if (acl)
152 		return true;
153 	if (default_acl)
154 		return true;
155 #if IS_ENABLED(CONFIG_SECURITY)
156 	if (dir->i_sb->s_security)
157 		return true;
158 #endif
159 	return false;
160 }
161 
162 
163 STATIC int
xfs_generic_create(struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,umode_t mode,dev_t rdev,struct file * tmpfile)164 xfs_generic_create(
165 	struct mnt_idmap	*idmap,
166 	struct inode		*dir,
167 	struct dentry		*dentry,
168 	umode_t			mode,
169 	dev_t			rdev,
170 	struct file		*tmpfile)	/* unnamed file */
171 {
172 	struct inode	*inode;
173 	struct xfs_inode *ip = NULL;
174 	struct posix_acl *default_acl, *acl;
175 	struct xfs_name	name;
176 	int		error;
177 
178 	/*
179 	 * Irix uses Missed'em'V split, but doesn't want to see
180 	 * the upper 5 bits of (14bit) major.
181 	 */
182 	if (S_ISCHR(mode) || S_ISBLK(mode)) {
183 		if (unlikely(!sysv_valid_dev(rdev) || MAJOR(rdev) & ~0x1ff))
184 			return -EINVAL;
185 	} else {
186 		rdev = 0;
187 	}
188 
189 	error = posix_acl_create(dir, &mode, &default_acl, &acl);
190 	if (error)
191 		return error;
192 
193 	/* Verify mode is valid also for tmpfile case */
194 	error = xfs_dentry_mode_to_name(&name, dentry, mode);
195 	if (unlikely(error))
196 		goto out_free_acl;
197 
198 	if (!tmpfile) {
199 		error = xfs_create(idmap, XFS_I(dir), &name, mode, rdev,
200 				xfs_create_need_xattr(dir, default_acl, acl),
201 				&ip);
202 	} else {
203 		error = xfs_create_tmpfile(idmap, XFS_I(dir), mode, &ip);
204 	}
205 	if (unlikely(error))
206 		goto out_free_acl;
207 
208 	inode = VFS_I(ip);
209 
210 	error = xfs_inode_init_security(inode, dir, &dentry->d_name);
211 	if (unlikely(error))
212 		goto out_cleanup_inode;
213 
214 	if (default_acl) {
215 		error = __xfs_set_acl(inode, default_acl, ACL_TYPE_DEFAULT);
216 		if (error)
217 			goto out_cleanup_inode;
218 	}
219 	if (acl) {
220 		error = __xfs_set_acl(inode, acl, ACL_TYPE_ACCESS);
221 		if (error)
222 			goto out_cleanup_inode;
223 	}
224 
225 	xfs_setup_iops(ip);
226 
227 	if (tmpfile) {
228 		/*
229 		 * The VFS requires that any inode fed to d_tmpfile must have
230 		 * nlink == 1 so that it can decrement the nlink in d_tmpfile.
231 		 * However, we created the temp file with nlink == 0 because
232 		 * we're not allowed to put an inode with nlink > 0 on the
233 		 * unlinked list.  Therefore we have to set nlink to 1 so that
234 		 * d_tmpfile can immediately set it back to zero.
235 		 */
236 		set_nlink(inode, 1);
237 		d_tmpfile(tmpfile, inode);
238 	} else
239 		d_instantiate(dentry, inode);
240 
241 	xfs_finish_inode_setup(ip);
242 
243  out_free_acl:
244 	posix_acl_release(default_acl);
245 	posix_acl_release(acl);
246 	return error;
247 
248  out_cleanup_inode:
249 	xfs_finish_inode_setup(ip);
250 	if (!tmpfile)
251 		xfs_cleanup_inode(dir, inode, dentry);
252 	xfs_irele(ip);
253 	goto out_free_acl;
254 }
255 
256 STATIC int
xfs_vn_mknod(struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,umode_t mode,dev_t rdev)257 xfs_vn_mknod(
258 	struct mnt_idmap	*idmap,
259 	struct inode		*dir,
260 	struct dentry		*dentry,
261 	umode_t			mode,
262 	dev_t			rdev)
263 {
264 	return xfs_generic_create(idmap, dir, dentry, mode, rdev, NULL);
265 }
266 
267 STATIC int
xfs_vn_create(struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,umode_t mode,bool flags)268 xfs_vn_create(
269 	struct mnt_idmap	*idmap,
270 	struct inode		*dir,
271 	struct dentry		*dentry,
272 	umode_t			mode,
273 	bool			flags)
274 {
275 	return xfs_generic_create(idmap, dir, dentry, mode, 0, NULL);
276 }
277 
278 STATIC int
xfs_vn_mkdir(struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,umode_t mode)279 xfs_vn_mkdir(
280 	struct mnt_idmap	*idmap,
281 	struct inode		*dir,
282 	struct dentry		*dentry,
283 	umode_t			mode)
284 {
285 	return xfs_generic_create(idmap, dir, dentry, mode | S_IFDIR, 0, NULL);
286 }
287 
288 STATIC struct dentry *
xfs_vn_lookup(struct inode * dir,struct dentry * dentry,unsigned int flags)289 xfs_vn_lookup(
290 	struct inode	*dir,
291 	struct dentry	*dentry,
292 	unsigned int flags)
293 {
294 	struct inode *inode;
295 	struct xfs_inode *cip;
296 	struct xfs_name	name;
297 	int		error;
298 
299 	if (dentry->d_name.len >= MAXNAMELEN)
300 		return ERR_PTR(-ENAMETOOLONG);
301 
302 	xfs_dentry_to_name(&name, dentry);
303 	error = xfs_lookup(XFS_I(dir), &name, &cip, NULL);
304 	if (likely(!error))
305 		inode = VFS_I(cip);
306 	else if (likely(error == -ENOENT))
307 		inode = NULL;
308 	else
309 		inode = ERR_PTR(error);
310 	return d_splice_alias(inode, dentry);
311 }
312 
313 STATIC struct dentry *
xfs_vn_ci_lookup(struct inode * dir,struct dentry * dentry,unsigned int flags)314 xfs_vn_ci_lookup(
315 	struct inode	*dir,
316 	struct dentry	*dentry,
317 	unsigned int flags)
318 {
319 	struct xfs_inode *ip;
320 	struct xfs_name	xname;
321 	struct xfs_name ci_name;
322 	struct qstr	dname;
323 	int		error;
324 
325 	if (dentry->d_name.len >= MAXNAMELEN)
326 		return ERR_PTR(-ENAMETOOLONG);
327 
328 	xfs_dentry_to_name(&xname, dentry);
329 	error = xfs_lookup(XFS_I(dir), &xname, &ip, &ci_name);
330 	if (unlikely(error)) {
331 		if (unlikely(error != -ENOENT))
332 			return ERR_PTR(error);
333 		/*
334 		 * call d_add(dentry, NULL) here when d_drop_negative_children
335 		 * is called in xfs_vn_mknod (ie. allow negative dentries
336 		 * with CI filesystems).
337 		 */
338 		return NULL;
339 	}
340 
341 	/* if exact match, just splice and exit */
342 	if (!ci_name.name)
343 		return d_splice_alias(VFS_I(ip), dentry);
344 
345 	/* else case-insensitive match... */
346 	dname.name = ci_name.name;
347 	dname.len = ci_name.len;
348 	dentry = d_add_ci(dentry, VFS_I(ip), &dname);
349 	kmem_free(ci_name.name);
350 	return dentry;
351 }
352 
353 STATIC int
xfs_vn_link(struct dentry * old_dentry,struct inode * dir,struct dentry * dentry)354 xfs_vn_link(
355 	struct dentry	*old_dentry,
356 	struct inode	*dir,
357 	struct dentry	*dentry)
358 {
359 	struct inode	*inode = d_inode(old_dentry);
360 	struct xfs_name	name;
361 	int		error;
362 
363 	error = xfs_dentry_mode_to_name(&name, dentry, inode->i_mode);
364 	if (unlikely(error))
365 		return error;
366 
367 	error = xfs_link(XFS_I(dir), XFS_I(inode), &name);
368 	if (unlikely(error))
369 		return error;
370 
371 	ihold(inode);
372 	d_instantiate(dentry, inode);
373 	return 0;
374 }
375 
376 STATIC int
xfs_vn_unlink(struct inode * dir,struct dentry * dentry)377 xfs_vn_unlink(
378 	struct inode	*dir,
379 	struct dentry	*dentry)
380 {
381 	struct xfs_name	name;
382 	int		error;
383 
384 	xfs_dentry_to_name(&name, dentry);
385 
386 	error = xfs_remove(XFS_I(dir), &name, XFS_I(d_inode(dentry)));
387 	if (error)
388 		return error;
389 
390 	/*
391 	 * With unlink, the VFS makes the dentry "negative": no inode,
392 	 * but still hashed. This is incompatible with case-insensitive
393 	 * mode, so invalidate (unhash) the dentry in CI-mode.
394 	 */
395 	if (xfs_has_asciici(XFS_M(dir->i_sb)))
396 		d_invalidate(dentry);
397 	return 0;
398 }
399 
400 STATIC int
xfs_vn_symlink(struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,const char * symname)401 xfs_vn_symlink(
402 	struct mnt_idmap	*idmap,
403 	struct inode		*dir,
404 	struct dentry		*dentry,
405 	const char		*symname)
406 {
407 	struct inode	*inode;
408 	struct xfs_inode *cip = NULL;
409 	struct xfs_name	name;
410 	int		error;
411 	umode_t		mode;
412 
413 	mode = S_IFLNK |
414 		(irix_symlink_mode ? 0777 & ~current_umask() : S_IRWXUGO);
415 	error = xfs_dentry_mode_to_name(&name, dentry, mode);
416 	if (unlikely(error))
417 		goto out;
418 
419 	error = xfs_symlink(idmap, XFS_I(dir), &name, symname, mode, &cip);
420 	if (unlikely(error))
421 		goto out;
422 
423 	inode = VFS_I(cip);
424 
425 	error = xfs_inode_init_security(inode, dir, &dentry->d_name);
426 	if (unlikely(error))
427 		goto out_cleanup_inode;
428 
429 	xfs_setup_iops(cip);
430 
431 	d_instantiate(dentry, inode);
432 	xfs_finish_inode_setup(cip);
433 	return 0;
434 
435  out_cleanup_inode:
436 	xfs_finish_inode_setup(cip);
437 	xfs_cleanup_inode(dir, inode, dentry);
438 	xfs_irele(cip);
439  out:
440 	return error;
441 }
442 
443 STATIC int
xfs_vn_rename(struct mnt_idmap * idmap,struct inode * odir,struct dentry * odentry,struct inode * ndir,struct dentry * ndentry,unsigned int flags)444 xfs_vn_rename(
445 	struct mnt_idmap	*idmap,
446 	struct inode		*odir,
447 	struct dentry		*odentry,
448 	struct inode		*ndir,
449 	struct dentry		*ndentry,
450 	unsigned int		flags)
451 {
452 	struct inode	*new_inode = d_inode(ndentry);
453 	int		omode = 0;
454 	int		error;
455 	struct xfs_name	oname;
456 	struct xfs_name	nname;
457 
458 	if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))
459 		return -EINVAL;
460 
461 	/* if we are exchanging files, we need to set i_mode of both files */
462 	if (flags & RENAME_EXCHANGE)
463 		omode = d_inode(ndentry)->i_mode;
464 
465 	error = xfs_dentry_mode_to_name(&oname, odentry, omode);
466 	if (omode && unlikely(error))
467 		return error;
468 
469 	error = xfs_dentry_mode_to_name(&nname, ndentry,
470 					d_inode(odentry)->i_mode);
471 	if (unlikely(error))
472 		return error;
473 
474 	return xfs_rename(idmap, XFS_I(odir), &oname,
475 			  XFS_I(d_inode(odentry)), XFS_I(ndir), &nname,
476 			  new_inode ? XFS_I(new_inode) : NULL, flags);
477 }
478 
479 /*
480  * careful here - this function can get called recursively, so
481  * we need to be very careful about how much stack we use.
482  * uio is kmalloced for this reason...
483  */
484 STATIC const char *
xfs_vn_get_link(struct dentry * dentry,struct inode * inode,struct delayed_call * done)485 xfs_vn_get_link(
486 	struct dentry		*dentry,
487 	struct inode		*inode,
488 	struct delayed_call	*done)
489 {
490 	char			*link;
491 	int			error = -ENOMEM;
492 
493 	if (!dentry)
494 		return ERR_PTR(-ECHILD);
495 
496 	link = kmalloc(XFS_SYMLINK_MAXLEN+1, GFP_KERNEL);
497 	if (!link)
498 		goto out_err;
499 
500 	error = xfs_readlink(XFS_I(d_inode(dentry)), link);
501 	if (unlikely(error))
502 		goto out_kfree;
503 
504 	set_delayed_call(done, kfree_link, link);
505 	return link;
506 
507  out_kfree:
508 	kfree(link);
509  out_err:
510 	return ERR_PTR(error);
511 }
512 
513 static uint32_t
xfs_stat_blksize(struct xfs_inode * ip)514 xfs_stat_blksize(
515 	struct xfs_inode	*ip)
516 {
517 	struct xfs_mount	*mp = ip->i_mount;
518 
519 	/*
520 	 * If the file blocks are being allocated from a realtime volume, then
521 	 * always return the realtime extent size.
522 	 */
523 	if (XFS_IS_REALTIME_INODE(ip))
524 		return XFS_FSB_TO_B(mp, xfs_get_extsz_hint(ip));
525 
526 	/*
527 	 * Allow large block sizes to be reported to userspace programs if the
528 	 * "largeio" mount option is used.
529 	 *
530 	 * If compatibility mode is specified, simply return the basic unit of
531 	 * caching so that we don't get inefficient read/modify/write I/O from
532 	 * user apps. Otherwise....
533 	 *
534 	 * If the underlying volume is a stripe, then return the stripe width in
535 	 * bytes as the recommended I/O size. It is not a stripe and we've set a
536 	 * default buffered I/O size, return that, otherwise return the compat
537 	 * default.
538 	 */
539 	if (xfs_has_large_iosize(mp)) {
540 		if (mp->m_swidth)
541 			return XFS_FSB_TO_B(mp, mp->m_swidth);
542 		if (xfs_has_allocsize(mp))
543 			return 1U << mp->m_allocsize_log;
544 	}
545 
546 	return PAGE_SIZE;
547 }
548 
549 STATIC int
xfs_vn_getattr(struct mnt_idmap * idmap,const struct path * path,struct kstat * stat,u32 request_mask,unsigned int query_flags)550 xfs_vn_getattr(
551 	struct mnt_idmap	*idmap,
552 	const struct path	*path,
553 	struct kstat		*stat,
554 	u32			request_mask,
555 	unsigned int		query_flags)
556 {
557 	struct inode		*inode = d_inode(path->dentry);
558 	struct xfs_inode	*ip = XFS_I(inode);
559 	struct xfs_mount	*mp = ip->i_mount;
560 	vfsuid_t		vfsuid = i_uid_into_vfsuid(idmap, inode);
561 	vfsgid_t		vfsgid = i_gid_into_vfsgid(idmap, inode);
562 
563 	trace_xfs_getattr(ip);
564 
565 	if (xfs_is_shutdown(mp))
566 		return -EIO;
567 
568 	stat->size = XFS_ISIZE(ip);
569 	stat->dev = inode->i_sb->s_dev;
570 	stat->mode = inode->i_mode;
571 	stat->nlink = inode->i_nlink;
572 	stat->uid = vfsuid_into_kuid(vfsuid);
573 	stat->gid = vfsgid_into_kgid(vfsgid);
574 	stat->ino = ip->i_ino;
575 	stat->atime = inode->i_atime;
576 	stat->mtime = inode->i_mtime;
577 	stat->ctime = inode_get_ctime(inode);
578 	stat->blocks = XFS_FSB_TO_BB(mp, ip->i_nblocks + ip->i_delayed_blks);
579 
580 	if (xfs_has_v3inodes(mp)) {
581 		if (request_mask & STATX_BTIME) {
582 			stat->result_mask |= STATX_BTIME;
583 			stat->btime = ip->i_crtime;
584 		}
585 	}
586 
587 	if ((request_mask & STATX_CHANGE_COOKIE) && IS_I_VERSION(inode)) {
588 		stat->change_cookie = inode_query_iversion(inode);
589 		stat->result_mask |= STATX_CHANGE_COOKIE;
590 	}
591 
592 	/*
593 	 * Note: If you add another clause to set an attribute flag, please
594 	 * update attributes_mask below.
595 	 */
596 	if (ip->i_diflags & XFS_DIFLAG_IMMUTABLE)
597 		stat->attributes |= STATX_ATTR_IMMUTABLE;
598 	if (ip->i_diflags & XFS_DIFLAG_APPEND)
599 		stat->attributes |= STATX_ATTR_APPEND;
600 	if (ip->i_diflags & XFS_DIFLAG_NODUMP)
601 		stat->attributes |= STATX_ATTR_NODUMP;
602 
603 	stat->attributes_mask |= (STATX_ATTR_IMMUTABLE |
604 				  STATX_ATTR_APPEND |
605 				  STATX_ATTR_NODUMP);
606 
607 	switch (inode->i_mode & S_IFMT) {
608 	case S_IFBLK:
609 	case S_IFCHR:
610 		stat->blksize = BLKDEV_IOSIZE;
611 		stat->rdev = inode->i_rdev;
612 		break;
613 	case S_IFREG:
614 		if (request_mask & STATX_DIOALIGN) {
615 			struct xfs_buftarg	*target = xfs_inode_buftarg(ip);
616 			struct block_device	*bdev = target->bt_bdev;
617 
618 			stat->result_mask |= STATX_DIOALIGN;
619 			stat->dio_mem_align = bdev_dma_alignment(bdev) + 1;
620 			stat->dio_offset_align = bdev_logical_block_size(bdev);
621 		}
622 		fallthrough;
623 	default:
624 		stat->blksize = xfs_stat_blksize(ip);
625 		stat->rdev = 0;
626 		break;
627 	}
628 
629 	return 0;
630 }
631 
632 static int
xfs_vn_change_ok(struct mnt_idmap * idmap,struct dentry * dentry,struct iattr * iattr)633 xfs_vn_change_ok(
634 	struct mnt_idmap	*idmap,
635 	struct dentry		*dentry,
636 	struct iattr		*iattr)
637 {
638 	struct xfs_mount	*mp = XFS_I(d_inode(dentry))->i_mount;
639 
640 	if (xfs_is_readonly(mp))
641 		return -EROFS;
642 
643 	if (xfs_is_shutdown(mp))
644 		return -EIO;
645 
646 	return setattr_prepare(idmap, dentry, iattr);
647 }
648 
649 /*
650  * Set non-size attributes of an inode.
651  *
652  * Caution: The caller of this function is responsible for calling
653  * setattr_prepare() or otherwise verifying the change is fine.
654  */
655 static int
xfs_setattr_nonsize(struct mnt_idmap * idmap,struct dentry * dentry,struct xfs_inode * ip,struct iattr * iattr)656 xfs_setattr_nonsize(
657 	struct mnt_idmap	*idmap,
658 	struct dentry		*dentry,
659 	struct xfs_inode	*ip,
660 	struct iattr		*iattr)
661 {
662 	xfs_mount_t		*mp = ip->i_mount;
663 	struct inode		*inode = VFS_I(ip);
664 	int			mask = iattr->ia_valid;
665 	xfs_trans_t		*tp;
666 	int			error;
667 	kuid_t			uid = GLOBAL_ROOT_UID;
668 	kgid_t			gid = GLOBAL_ROOT_GID;
669 	struct xfs_dquot	*udqp = NULL, *gdqp = NULL;
670 	struct xfs_dquot	*old_udqp = NULL, *old_gdqp = NULL;
671 
672 	ASSERT((mask & ATTR_SIZE) == 0);
673 
674 	/*
675 	 * If disk quotas is on, we make sure that the dquots do exist on disk,
676 	 * before we start any other transactions. Trying to do this later
677 	 * is messy. We don't care to take a readlock to look at the ids
678 	 * in inode here, because we can't hold it across the trans_reserve.
679 	 * If the IDs do change before we take the ilock, we're covered
680 	 * because the i_*dquot fields will get updated anyway.
681 	 */
682 	if (XFS_IS_QUOTA_ON(mp) && (mask & (ATTR_UID|ATTR_GID))) {
683 		uint	qflags = 0;
684 
685 		if ((mask & ATTR_UID) && XFS_IS_UQUOTA_ON(mp)) {
686 			uid = from_vfsuid(idmap, i_user_ns(inode),
687 					  iattr->ia_vfsuid);
688 			qflags |= XFS_QMOPT_UQUOTA;
689 		} else {
690 			uid = inode->i_uid;
691 		}
692 		if ((mask & ATTR_GID) && XFS_IS_GQUOTA_ON(mp)) {
693 			gid = from_vfsgid(idmap, i_user_ns(inode),
694 					  iattr->ia_vfsgid);
695 			qflags |= XFS_QMOPT_GQUOTA;
696 		}  else {
697 			gid = inode->i_gid;
698 		}
699 
700 		/*
701 		 * We take a reference when we initialize udqp and gdqp,
702 		 * so it is important that we never blindly double trip on
703 		 * the same variable. See xfs_create() for an example.
704 		 */
705 		ASSERT(udqp == NULL);
706 		ASSERT(gdqp == NULL);
707 		error = xfs_qm_vop_dqalloc(ip, uid, gid, ip->i_projid,
708 					   qflags, &udqp, &gdqp, NULL);
709 		if (error)
710 			return error;
711 	}
712 
713 	error = xfs_trans_alloc_ichange(ip, udqp, gdqp, NULL,
714 			has_capability_noaudit(current, CAP_FOWNER), &tp);
715 	if (error)
716 		goto out_dqrele;
717 
718 	/*
719 	 * Register quota modifications in the transaction.  Must be the owner
720 	 * or privileged.  These IDs could have changed since we last looked at
721 	 * them.  But, we're assured that if the ownership did change while we
722 	 * didn't have the inode locked, inode's dquot(s) would have changed
723 	 * also.
724 	 */
725 	if (XFS_IS_UQUOTA_ON(mp) &&
726 	    i_uid_needs_update(idmap, iattr, inode)) {
727 		ASSERT(udqp);
728 		old_udqp = xfs_qm_vop_chown(tp, ip, &ip->i_udquot, udqp);
729 	}
730 	if (XFS_IS_GQUOTA_ON(mp) &&
731 	    i_gid_needs_update(idmap, iattr, inode)) {
732 		ASSERT(xfs_has_pquotino(mp) || !XFS_IS_PQUOTA_ON(mp));
733 		ASSERT(gdqp);
734 		old_gdqp = xfs_qm_vop_chown(tp, ip, &ip->i_gdquot, gdqp);
735 	}
736 
737 	setattr_copy(idmap, inode, iattr);
738 	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
739 
740 	XFS_STATS_INC(mp, xs_ig_attrchg);
741 
742 	if (xfs_has_wsync(mp))
743 		xfs_trans_set_sync(tp);
744 	error = xfs_trans_commit(tp);
745 
746 	/*
747 	 * Release any dquot(s) the inode had kept before chown.
748 	 */
749 	xfs_qm_dqrele(old_udqp);
750 	xfs_qm_dqrele(old_gdqp);
751 	xfs_qm_dqrele(udqp);
752 	xfs_qm_dqrele(gdqp);
753 
754 	if (error)
755 		return error;
756 
757 	/*
758 	 * XXX(hch): Updating the ACL entries is not atomic vs the i_mode
759 	 * 	     update.  We could avoid this with linked transactions
760 	 * 	     and passing down the transaction pointer all the way
761 	 *	     to attr_set.  No previous user of the generic
762 	 * 	     Posix ACL code seems to care about this issue either.
763 	 */
764 	if (mask & ATTR_MODE) {
765 		error = posix_acl_chmod(idmap, dentry, inode->i_mode);
766 		if (error)
767 			return error;
768 	}
769 
770 	return 0;
771 
772 out_dqrele:
773 	xfs_qm_dqrele(udqp);
774 	xfs_qm_dqrele(gdqp);
775 	return error;
776 }
777 
778 /*
779  * Truncate file.  Must have write permission and not be a directory.
780  *
781  * Caution: The caller of this function is responsible for calling
782  * setattr_prepare() or otherwise verifying the change is fine.
783  */
784 STATIC int
xfs_setattr_size(struct mnt_idmap * idmap,struct dentry * dentry,struct xfs_inode * ip,struct iattr * iattr)785 xfs_setattr_size(
786 	struct mnt_idmap	*idmap,
787 	struct dentry		*dentry,
788 	struct xfs_inode	*ip,
789 	struct iattr		*iattr)
790 {
791 	struct xfs_mount	*mp = ip->i_mount;
792 	struct inode		*inode = VFS_I(ip);
793 	xfs_off_t		oldsize, newsize;
794 	struct xfs_trans	*tp;
795 	int			error;
796 	uint			lock_flags = 0;
797 	bool			did_zeroing = false;
798 
799 	ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
800 	ASSERT(xfs_isilocked(ip, XFS_MMAPLOCK_EXCL));
801 	ASSERT(S_ISREG(inode->i_mode));
802 	ASSERT((iattr->ia_valid & (ATTR_UID|ATTR_GID|ATTR_ATIME|ATTR_ATIME_SET|
803 		ATTR_MTIME_SET|ATTR_TIMES_SET)) == 0);
804 
805 	oldsize = inode->i_size;
806 	newsize = iattr->ia_size;
807 
808 	/*
809 	 * Short circuit the truncate case for zero length files.
810 	 */
811 	if (newsize == 0 && oldsize == 0 && ip->i_df.if_nextents == 0) {
812 		if (!(iattr->ia_valid & (ATTR_CTIME|ATTR_MTIME)))
813 			return 0;
814 
815 		/*
816 		 * Use the regular setattr path to update the timestamps.
817 		 */
818 		iattr->ia_valid &= ~ATTR_SIZE;
819 		return xfs_setattr_nonsize(idmap, dentry, ip, iattr);
820 	}
821 
822 	/*
823 	 * Make sure that the dquots are attached to the inode.
824 	 */
825 	error = xfs_qm_dqattach(ip);
826 	if (error)
827 		return error;
828 
829 	/*
830 	 * Wait for all direct I/O to complete.
831 	 */
832 	inode_dio_wait(inode);
833 
834 	/*
835 	 * File data changes must be complete before we start the transaction to
836 	 * modify the inode.  This needs to be done before joining the inode to
837 	 * the transaction because the inode cannot be unlocked once it is a
838 	 * part of the transaction.
839 	 *
840 	 * Start with zeroing any data beyond EOF that we may expose on file
841 	 * extension, or zeroing out the rest of the block on a downward
842 	 * truncate.
843 	 */
844 	if (newsize > oldsize) {
845 		trace_xfs_zero_eof(ip, oldsize, newsize - oldsize);
846 		error = xfs_zero_range(ip, oldsize, newsize - oldsize,
847 				&did_zeroing);
848 	} else {
849 		/*
850 		 * iomap won't detect a dirty page over an unwritten block (or a
851 		 * cow block over a hole) and subsequently skips zeroing the
852 		 * newly post-EOF portion of the page. Flush the new EOF to
853 		 * convert the block before the pagecache truncate.
854 		 */
855 		error = filemap_write_and_wait_range(inode->i_mapping, newsize,
856 						     newsize);
857 		if (error)
858 			return error;
859 		error = xfs_truncate_page(ip, newsize, &did_zeroing);
860 	}
861 
862 	if (error)
863 		return error;
864 
865 	/*
866 	 * We've already locked out new page faults, so now we can safely remove
867 	 * pages from the page cache knowing they won't get refaulted until we
868 	 * drop the XFS_MMAP_EXCL lock after the extent manipulations are
869 	 * complete. The truncate_setsize() call also cleans partial EOF page
870 	 * PTEs on extending truncates and hence ensures sub-page block size
871 	 * filesystems are correctly handled, too.
872 	 *
873 	 * We have to do all the page cache truncate work outside the
874 	 * transaction context as the "lock" order is page lock->log space
875 	 * reservation as defined by extent allocation in the writeback path.
876 	 * Hence a truncate can fail with ENOMEM from xfs_trans_alloc(), but
877 	 * having already truncated the in-memory version of the file (i.e. made
878 	 * user visible changes). There's not much we can do about this, except
879 	 * to hope that the caller sees ENOMEM and retries the truncate
880 	 * operation.
881 	 *
882 	 * And we update in-core i_size and truncate page cache beyond newsize
883 	 * before writeback the [i_disk_size, newsize] range, so we're
884 	 * guaranteed not to write stale data past the new EOF on truncate down.
885 	 */
886 	truncate_setsize(inode, newsize);
887 
888 	/*
889 	 * We are going to log the inode size change in this transaction so
890 	 * any previous writes that are beyond the on disk EOF and the new
891 	 * EOF that have not been written out need to be written here.  If we
892 	 * do not write the data out, we expose ourselves to the null files
893 	 * problem. Note that this includes any block zeroing we did above;
894 	 * otherwise those blocks may not be zeroed after a crash.
895 	 */
896 	if (did_zeroing ||
897 	    (newsize > ip->i_disk_size && oldsize != ip->i_disk_size)) {
898 		error = filemap_write_and_wait_range(VFS_I(ip)->i_mapping,
899 						ip->i_disk_size, newsize - 1);
900 		if (error)
901 			return error;
902 	}
903 
904 	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp);
905 	if (error)
906 		return error;
907 
908 	lock_flags |= XFS_ILOCK_EXCL;
909 	xfs_ilock(ip, XFS_ILOCK_EXCL);
910 	xfs_trans_ijoin(tp, ip, 0);
911 
912 	/*
913 	 * Only change the c/mtime if we are changing the size or we are
914 	 * explicitly asked to change it.  This handles the semantic difference
915 	 * between truncate() and ftruncate() as implemented in the VFS.
916 	 *
917 	 * The regular truncate() case without ATTR_CTIME and ATTR_MTIME is a
918 	 * special case where we need to update the times despite not having
919 	 * these flags set.  For all other operations the VFS set these flags
920 	 * explicitly if it wants a timestamp update.
921 	 */
922 	if (newsize != oldsize &&
923 	    !(iattr->ia_valid & (ATTR_CTIME | ATTR_MTIME))) {
924 		iattr->ia_ctime = iattr->ia_mtime =
925 			current_time(inode);
926 		iattr->ia_valid |= ATTR_CTIME | ATTR_MTIME;
927 	}
928 
929 	/*
930 	 * The first thing we do is set the size to new_size permanently on
931 	 * disk.  This way we don't have to worry about anyone ever being able
932 	 * to look at the data being freed even in the face of a crash.
933 	 * What we're getting around here is the case where we free a block, it
934 	 * is allocated to another file, it is written to, and then we crash.
935 	 * If the new data gets written to the file but the log buffers
936 	 * containing the free and reallocation don't, then we'd end up with
937 	 * garbage in the blocks being freed.  As long as we make the new size
938 	 * permanent before actually freeing any blocks it doesn't matter if
939 	 * they get written to.
940 	 */
941 	ip->i_disk_size = newsize;
942 	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
943 
944 	if (newsize <= oldsize) {
945 		error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, newsize);
946 		if (error)
947 			goto out_trans_cancel;
948 
949 		/*
950 		 * Truncated "down", so we're removing references to old data
951 		 * here - if we delay flushing for a long time, we expose
952 		 * ourselves unduly to the notorious NULL files problem.  So,
953 		 * we mark this inode and flush it when the file is closed,
954 		 * and do not wait the usual (long) time for writeout.
955 		 */
956 		xfs_iflags_set(ip, XFS_ITRUNCATED);
957 
958 		/* A truncate down always removes post-EOF blocks. */
959 		xfs_inode_clear_eofblocks_tag(ip);
960 	}
961 
962 	ASSERT(!(iattr->ia_valid & (ATTR_UID | ATTR_GID)));
963 	setattr_copy(idmap, inode, iattr);
964 	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
965 
966 	XFS_STATS_INC(mp, xs_ig_attrchg);
967 
968 	if (xfs_has_wsync(mp))
969 		xfs_trans_set_sync(tp);
970 
971 	error = xfs_trans_commit(tp);
972 out_unlock:
973 	if (lock_flags)
974 		xfs_iunlock(ip, lock_flags);
975 	return error;
976 
977 out_trans_cancel:
978 	xfs_trans_cancel(tp);
979 	goto out_unlock;
980 }
981 
982 int
xfs_vn_setattr_size(struct mnt_idmap * idmap,struct dentry * dentry,struct iattr * iattr)983 xfs_vn_setattr_size(
984 	struct mnt_idmap	*idmap,
985 	struct dentry		*dentry,
986 	struct iattr		*iattr)
987 {
988 	struct xfs_inode	*ip = XFS_I(d_inode(dentry));
989 	int error;
990 
991 	trace_xfs_setattr(ip);
992 
993 	error = xfs_vn_change_ok(idmap, dentry, iattr);
994 	if (error)
995 		return error;
996 	return xfs_setattr_size(idmap, dentry, ip, iattr);
997 }
998 
999 STATIC int
xfs_vn_setattr(struct mnt_idmap * idmap,struct dentry * dentry,struct iattr * iattr)1000 xfs_vn_setattr(
1001 	struct mnt_idmap	*idmap,
1002 	struct dentry		*dentry,
1003 	struct iattr		*iattr)
1004 {
1005 	struct inode		*inode = d_inode(dentry);
1006 	struct xfs_inode	*ip = XFS_I(inode);
1007 	int			error;
1008 
1009 	if (iattr->ia_valid & ATTR_SIZE) {
1010 		uint			iolock;
1011 
1012 		xfs_ilock(ip, XFS_MMAPLOCK_EXCL);
1013 		iolock = XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL;
1014 
1015 		error = xfs_break_layouts(inode, &iolock, BREAK_UNMAP);
1016 		if (error) {
1017 			xfs_iunlock(ip, XFS_MMAPLOCK_EXCL);
1018 			return error;
1019 		}
1020 
1021 		error = xfs_vn_setattr_size(idmap, dentry, iattr);
1022 		xfs_iunlock(ip, XFS_MMAPLOCK_EXCL);
1023 	} else {
1024 		trace_xfs_setattr(ip);
1025 
1026 		error = xfs_vn_change_ok(idmap, dentry, iattr);
1027 		if (!error)
1028 			error = xfs_setattr_nonsize(idmap, dentry, ip, iattr);
1029 	}
1030 
1031 	return error;
1032 }
1033 
1034 STATIC int
xfs_vn_update_time(struct inode * inode,int flags)1035 xfs_vn_update_time(
1036 	struct inode		*inode,
1037 	int			flags)
1038 {
1039 	struct xfs_inode	*ip = XFS_I(inode);
1040 	struct xfs_mount	*mp = ip->i_mount;
1041 	int			log_flags = XFS_ILOG_TIMESTAMP;
1042 	struct xfs_trans	*tp;
1043 	int			error;
1044 	struct timespec64	now;
1045 
1046 	trace_xfs_update_time(ip);
1047 
1048 	if (inode->i_sb->s_flags & SB_LAZYTIME) {
1049 		if (!((flags & S_VERSION) &&
1050 		      inode_maybe_inc_iversion(inode, false))) {
1051 			generic_update_time(inode, flags);
1052 			return 0;
1053 		}
1054 
1055 		/* Capture the iversion update that just occurred */
1056 		log_flags |= XFS_ILOG_CORE;
1057 	}
1058 
1059 	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_fsyncts, 0, 0, 0, &tp);
1060 	if (error)
1061 		return error;
1062 
1063 	xfs_ilock(ip, XFS_ILOCK_EXCL);
1064 	if (flags & (S_CTIME|S_MTIME))
1065 		now = inode_set_ctime_current(inode);
1066 	else
1067 		now = current_time(inode);
1068 
1069 	if (flags & S_MTIME)
1070 		inode->i_mtime = now;
1071 	if (flags & S_ATIME)
1072 		inode->i_atime = now;
1073 
1074 	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
1075 	xfs_trans_log_inode(tp, ip, log_flags);
1076 	return xfs_trans_commit(tp);
1077 }
1078 
1079 STATIC int
xfs_vn_fiemap(struct inode * inode,struct fiemap_extent_info * fieinfo,u64 start,u64 length)1080 xfs_vn_fiemap(
1081 	struct inode		*inode,
1082 	struct fiemap_extent_info *fieinfo,
1083 	u64			start,
1084 	u64			length)
1085 {
1086 	int			error;
1087 
1088 	xfs_ilock(XFS_I(inode), XFS_IOLOCK_SHARED);
1089 	if (fieinfo->fi_flags & FIEMAP_FLAG_XATTR) {
1090 		fieinfo->fi_flags &= ~FIEMAP_FLAG_XATTR;
1091 		error = iomap_fiemap(inode, fieinfo, start, length,
1092 				&xfs_xattr_iomap_ops);
1093 	} else {
1094 		error = iomap_fiemap(inode, fieinfo, start, length,
1095 				&xfs_read_iomap_ops);
1096 	}
1097 	xfs_iunlock(XFS_I(inode), XFS_IOLOCK_SHARED);
1098 
1099 	return error;
1100 }
1101 
1102 STATIC int
xfs_vn_tmpfile(struct mnt_idmap * idmap,struct inode * dir,struct file * file,umode_t mode)1103 xfs_vn_tmpfile(
1104 	struct mnt_idmap	*idmap,
1105 	struct inode		*dir,
1106 	struct file		*file,
1107 	umode_t			mode)
1108 {
1109 	int err = xfs_generic_create(idmap, dir, file->f_path.dentry, mode, 0, file);
1110 
1111 	return finish_open_simple(file, err);
1112 }
1113 
1114 static const struct inode_operations xfs_inode_operations = {
1115 	.get_inode_acl		= xfs_get_acl,
1116 	.set_acl		= xfs_set_acl,
1117 	.getattr		= xfs_vn_getattr,
1118 	.setattr		= xfs_vn_setattr,
1119 	.listxattr		= xfs_vn_listxattr,
1120 	.fiemap			= xfs_vn_fiemap,
1121 	.update_time		= xfs_vn_update_time,
1122 	.fileattr_get		= xfs_fileattr_get,
1123 	.fileattr_set		= xfs_fileattr_set,
1124 };
1125 
1126 static const struct inode_operations xfs_dir_inode_operations = {
1127 	.create			= xfs_vn_create,
1128 	.lookup			= xfs_vn_lookup,
1129 	.link			= xfs_vn_link,
1130 	.unlink			= xfs_vn_unlink,
1131 	.symlink		= xfs_vn_symlink,
1132 	.mkdir			= xfs_vn_mkdir,
1133 	/*
1134 	 * Yes, XFS uses the same method for rmdir and unlink.
1135 	 *
1136 	 * There are some subtile differences deeper in the code,
1137 	 * but we use S_ISDIR to check for those.
1138 	 */
1139 	.rmdir			= xfs_vn_unlink,
1140 	.mknod			= xfs_vn_mknod,
1141 	.rename			= xfs_vn_rename,
1142 	.get_inode_acl		= xfs_get_acl,
1143 	.set_acl		= xfs_set_acl,
1144 	.getattr		= xfs_vn_getattr,
1145 	.setattr		= xfs_vn_setattr,
1146 	.listxattr		= xfs_vn_listxattr,
1147 	.update_time		= xfs_vn_update_time,
1148 	.tmpfile		= xfs_vn_tmpfile,
1149 	.fileattr_get		= xfs_fileattr_get,
1150 	.fileattr_set		= xfs_fileattr_set,
1151 };
1152 
1153 static const struct inode_operations xfs_dir_ci_inode_operations = {
1154 	.create			= xfs_vn_create,
1155 	.lookup			= xfs_vn_ci_lookup,
1156 	.link			= xfs_vn_link,
1157 	.unlink			= xfs_vn_unlink,
1158 	.symlink		= xfs_vn_symlink,
1159 	.mkdir			= xfs_vn_mkdir,
1160 	/*
1161 	 * Yes, XFS uses the same method for rmdir and unlink.
1162 	 *
1163 	 * There are some subtile differences deeper in the code,
1164 	 * but we use S_ISDIR to check for those.
1165 	 */
1166 	.rmdir			= xfs_vn_unlink,
1167 	.mknod			= xfs_vn_mknod,
1168 	.rename			= xfs_vn_rename,
1169 	.get_inode_acl		= xfs_get_acl,
1170 	.set_acl		= xfs_set_acl,
1171 	.getattr		= xfs_vn_getattr,
1172 	.setattr		= xfs_vn_setattr,
1173 	.listxattr		= xfs_vn_listxattr,
1174 	.update_time		= xfs_vn_update_time,
1175 	.tmpfile		= xfs_vn_tmpfile,
1176 	.fileattr_get		= xfs_fileattr_get,
1177 	.fileattr_set		= xfs_fileattr_set,
1178 };
1179 
1180 static const struct inode_operations xfs_symlink_inode_operations = {
1181 	.get_link		= xfs_vn_get_link,
1182 	.getattr		= xfs_vn_getattr,
1183 	.setattr		= xfs_vn_setattr,
1184 	.listxattr		= xfs_vn_listxattr,
1185 	.update_time		= xfs_vn_update_time,
1186 };
1187 
1188 /* Figure out if this file actually supports DAX. */
1189 static bool
xfs_inode_supports_dax(struct xfs_inode * ip)1190 xfs_inode_supports_dax(
1191 	struct xfs_inode	*ip)
1192 {
1193 	struct xfs_mount	*mp = ip->i_mount;
1194 
1195 	/* Only supported on regular files. */
1196 	if (!S_ISREG(VFS_I(ip)->i_mode))
1197 		return false;
1198 
1199 	/* Block size must match page size */
1200 	if (mp->m_sb.sb_blocksize != PAGE_SIZE)
1201 		return false;
1202 
1203 	/* Device has to support DAX too. */
1204 	return xfs_inode_buftarg(ip)->bt_daxdev != NULL;
1205 }
1206 
1207 static bool
xfs_inode_should_enable_dax(struct xfs_inode * ip)1208 xfs_inode_should_enable_dax(
1209 	struct xfs_inode *ip)
1210 {
1211 	if (!IS_ENABLED(CONFIG_FS_DAX))
1212 		return false;
1213 	if (xfs_has_dax_never(ip->i_mount))
1214 		return false;
1215 	if (!xfs_inode_supports_dax(ip))
1216 		return false;
1217 	if (xfs_has_dax_always(ip->i_mount))
1218 		return true;
1219 	if (ip->i_diflags2 & XFS_DIFLAG2_DAX)
1220 		return true;
1221 	return false;
1222 }
1223 
1224 void
xfs_diflags_to_iflags(struct xfs_inode * ip,bool init)1225 xfs_diflags_to_iflags(
1226 	struct xfs_inode	*ip,
1227 	bool init)
1228 {
1229 	struct inode            *inode = VFS_I(ip);
1230 	unsigned int            xflags = xfs_ip2xflags(ip);
1231 	unsigned int            flags = 0;
1232 
1233 	ASSERT(!(IS_DAX(inode) && init));
1234 
1235 	if (xflags & FS_XFLAG_IMMUTABLE)
1236 		flags |= S_IMMUTABLE;
1237 	if (xflags & FS_XFLAG_APPEND)
1238 		flags |= S_APPEND;
1239 	if (xflags & FS_XFLAG_SYNC)
1240 		flags |= S_SYNC;
1241 	if (xflags & FS_XFLAG_NOATIME)
1242 		flags |= S_NOATIME;
1243 	if (init && xfs_inode_should_enable_dax(ip))
1244 		flags |= S_DAX;
1245 
1246 	/*
1247 	 * S_DAX can only be set during inode initialization and is never set by
1248 	 * the VFS, so we cannot mask off S_DAX in i_flags.
1249 	 */
1250 	inode->i_flags &= ~(S_IMMUTABLE | S_APPEND | S_SYNC | S_NOATIME);
1251 	inode->i_flags |= flags;
1252 }
1253 
1254 /*
1255  * Initialize the Linux inode.
1256  *
1257  * When reading existing inodes from disk this is called directly from xfs_iget,
1258  * when creating a new inode it is called from xfs_init_new_inode after setting
1259  * up the inode. These callers have different criteria for clearing XFS_INEW, so
1260  * leave it up to the caller to deal with unlocking the inode appropriately.
1261  */
1262 void
xfs_setup_inode(struct xfs_inode * ip)1263 xfs_setup_inode(
1264 	struct xfs_inode	*ip)
1265 {
1266 	struct inode		*inode = &ip->i_vnode;
1267 	gfp_t			gfp_mask;
1268 
1269 	inode->i_ino = ip->i_ino;
1270 	inode->i_state |= I_NEW;
1271 
1272 	inode_sb_list_add(inode);
1273 	/* make the inode look hashed for the writeback code */
1274 	inode_fake_hash(inode);
1275 
1276 	i_size_write(inode, ip->i_disk_size);
1277 	xfs_diflags_to_iflags(ip, true);
1278 
1279 	if (S_ISDIR(inode->i_mode)) {
1280 		/*
1281 		 * We set the i_rwsem class here to avoid potential races with
1282 		 * lockdep_annotate_inode_mutex_key() reinitialising the lock
1283 		 * after a filehandle lookup has already found the inode in
1284 		 * cache before it has been unlocked via unlock_new_inode().
1285 		 */
1286 		lockdep_set_class(&inode->i_rwsem,
1287 				  &inode->i_sb->s_type->i_mutex_dir_key);
1288 		lockdep_set_class(&ip->i_lock.mr_lock, &xfs_dir_ilock_class);
1289 	} else {
1290 		lockdep_set_class(&ip->i_lock.mr_lock, &xfs_nondir_ilock_class);
1291 	}
1292 
1293 	/*
1294 	 * Ensure all page cache allocations are done from GFP_NOFS context to
1295 	 * prevent direct reclaim recursion back into the filesystem and blowing
1296 	 * stacks or deadlocking.
1297 	 */
1298 	gfp_mask = mapping_gfp_mask(inode->i_mapping);
1299 	mapping_set_gfp_mask(inode->i_mapping, (gfp_mask & ~(__GFP_FS)));
1300 
1301 	/*
1302 	 * For real-time inodes update the stable write flags to that of the RT
1303 	 * device instead of the data device.
1304 	 */
1305 	if (S_ISREG(inode->i_mode) && XFS_IS_REALTIME_INODE(ip))
1306 		xfs_update_stable_writes(ip);
1307 
1308 	/*
1309 	 * If there is no attribute fork no ACL can exist on this inode,
1310 	 * and it can't have any file capabilities attached to it either.
1311 	 */
1312 	if (!xfs_inode_has_attr_fork(ip)) {
1313 		inode_has_no_xattr(inode);
1314 		cache_no_acl(inode);
1315 	}
1316 }
1317 
1318 void
xfs_setup_iops(struct xfs_inode * ip)1319 xfs_setup_iops(
1320 	struct xfs_inode	*ip)
1321 {
1322 	struct inode		*inode = &ip->i_vnode;
1323 
1324 	switch (inode->i_mode & S_IFMT) {
1325 	case S_IFREG:
1326 		inode->i_op = &xfs_inode_operations;
1327 		inode->i_fop = &xfs_file_operations;
1328 		if (IS_DAX(inode))
1329 			inode->i_mapping->a_ops = &xfs_dax_aops;
1330 		else
1331 			inode->i_mapping->a_ops = &xfs_address_space_operations;
1332 		break;
1333 	case S_IFDIR:
1334 		if (xfs_has_asciici(XFS_M(inode->i_sb)))
1335 			inode->i_op = &xfs_dir_ci_inode_operations;
1336 		else
1337 			inode->i_op = &xfs_dir_inode_operations;
1338 		inode->i_fop = &xfs_dir_file_operations;
1339 		break;
1340 	case S_IFLNK:
1341 		inode->i_op = &xfs_symlink_inode_operations;
1342 		break;
1343 	default:
1344 		inode->i_op = &xfs_inode_operations;
1345 		init_special_inode(inode, inode->i_mode, inode->i_rdev);
1346 		break;
1347 	}
1348 }
1349