1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2000-2006 Silicon Graphics, Inc.
4  * All Rights Reserved.
5  */
6 
7 #include "xfs.h"
8 #include "xfs_fs.h"
9 #include "xfs_shared.h"
10 #include "xfs_format.h"
11 #include "xfs_log_format.h"
12 #include "xfs_trans_resv.h"
13 #include "xfs_mount.h"
14 #include "xfs_inode.h"
15 #include "xfs_trans.h"
16 #include "xfs_inode_item.h"
17 #include "xfs_btree.h"
18 #include "xfs_bmap_btree.h"
19 #include "xfs_bmap.h"
20 #include "xfs_error.h"
21 #include "xfs_trace.h"
22 #include "xfs_da_format.h"
23 #include "xfs_da_btree.h"
24 #include "xfs_dir2_priv.h"
25 #include "xfs_attr_leaf.h"
26 #include "xfs_types.h"
27 #include "xfs_errortag.h"
28 
29 struct kmem_cache *xfs_ifork_cache;
30 
31 void
xfs_init_local_fork(struct xfs_inode * ip,int whichfork,const void * data,int64_t size)32 xfs_init_local_fork(
33 	struct xfs_inode	*ip,
34 	int			whichfork,
35 	const void		*data,
36 	int64_t			size)
37 {
38 	struct xfs_ifork	*ifp = xfs_ifork_ptr(ip, whichfork);
39 	int			mem_size = size;
40 	bool			zero_terminate;
41 
42 	/*
43 	 * If we are using the local fork to store a symlink body we need to
44 	 * zero-terminate it so that we can pass it back to the VFS directly.
45 	 * Overallocate the in-memory fork by one for that and add a zero
46 	 * to terminate it below.
47 	 */
48 	zero_terminate = S_ISLNK(VFS_I(ip)->i_mode);
49 	if (zero_terminate)
50 		mem_size++;
51 
52 	if (size) {
53 		ifp->if_u1.if_data = kmem_alloc(mem_size, KM_NOFS);
54 		memcpy(ifp->if_u1.if_data, data, size);
55 		if (zero_terminate)
56 			ifp->if_u1.if_data[size] = '\0';
57 	} else {
58 		ifp->if_u1.if_data = NULL;
59 	}
60 
61 	ifp->if_bytes = size;
62 }
63 
64 /*
65  * The file is in-lined in the on-disk inode.
66  */
67 STATIC int
xfs_iformat_local(struct xfs_inode * ip,struct xfs_dinode * dip,int whichfork,int size)68 xfs_iformat_local(
69 	struct xfs_inode	*ip,
70 	struct xfs_dinode	*dip,
71 	int			whichfork,
72 	int			size)
73 {
74 	/*
75 	 * If the size is unreasonable, then something
76 	 * is wrong and we just bail out rather than crash in
77 	 * kmem_alloc() or memcpy() below.
78 	 */
79 	if (unlikely(size > XFS_DFORK_SIZE(dip, ip->i_mount, whichfork))) {
80 		xfs_warn(ip->i_mount,
81 	"corrupt inode %llu (bad size %d for local fork, size = %zd).",
82 			(unsigned long long) ip->i_ino, size,
83 			XFS_DFORK_SIZE(dip, ip->i_mount, whichfork));
84 		xfs_inode_verifier_error(ip, -EFSCORRUPTED,
85 				"xfs_iformat_local", dip, sizeof(*dip),
86 				__this_address);
87 		return -EFSCORRUPTED;
88 	}
89 
90 	xfs_init_local_fork(ip, whichfork, XFS_DFORK_PTR(dip, whichfork), size);
91 	return 0;
92 }
93 
94 /*
95  * The file consists of a set of extents all of which fit into the on-disk
96  * inode.
97  */
98 STATIC int
xfs_iformat_extents(struct xfs_inode * ip,struct xfs_dinode * dip,int whichfork)99 xfs_iformat_extents(
100 	struct xfs_inode	*ip,
101 	struct xfs_dinode	*dip,
102 	int			whichfork)
103 {
104 	struct xfs_mount	*mp = ip->i_mount;
105 	struct xfs_ifork	*ifp = xfs_ifork_ptr(ip, whichfork);
106 	int			state = xfs_bmap_fork_to_state(whichfork);
107 	xfs_extnum_t		nex = xfs_dfork_nextents(dip, whichfork);
108 	int			size = nex * sizeof(xfs_bmbt_rec_t);
109 	struct xfs_iext_cursor	icur;
110 	struct xfs_bmbt_rec	*dp;
111 	struct xfs_bmbt_irec	new;
112 	int			i;
113 
114 	/*
115 	 * If the number of extents is unreasonable, then something is wrong and
116 	 * we just bail out rather than crash in kmem_alloc() or memcpy() below.
117 	 */
118 	if (unlikely(size < 0 || size > XFS_DFORK_SIZE(dip, mp, whichfork))) {
119 		xfs_warn(ip->i_mount, "corrupt inode %llu ((a)extents = %llu).",
120 			ip->i_ino, nex);
121 		xfs_inode_verifier_error(ip, -EFSCORRUPTED,
122 				"xfs_iformat_extents(1)", dip, sizeof(*dip),
123 				__this_address);
124 		return -EFSCORRUPTED;
125 	}
126 
127 	ifp->if_bytes = 0;
128 	ifp->if_u1.if_root = NULL;
129 	ifp->if_height = 0;
130 	if (size) {
131 		dp = (xfs_bmbt_rec_t *) XFS_DFORK_PTR(dip, whichfork);
132 
133 		xfs_iext_first(ifp, &icur);
134 		for (i = 0; i < nex; i++, dp++) {
135 			xfs_failaddr_t	fa;
136 
137 			xfs_bmbt_disk_get_all(dp, &new);
138 			fa = xfs_bmap_validate_extent(ip, whichfork, &new);
139 			if (fa) {
140 				xfs_inode_verifier_error(ip, -EFSCORRUPTED,
141 						"xfs_iformat_extents(2)",
142 						dp, sizeof(*dp), fa);
143 				return -EFSCORRUPTED;
144 			}
145 
146 			xfs_iext_insert(ip, &icur, &new, state);
147 			trace_xfs_read_extent(ip, &icur, state, _THIS_IP_);
148 			xfs_iext_next(ifp, &icur);
149 		}
150 	}
151 	return 0;
152 }
153 
154 /*
155  * The file has too many extents to fit into
156  * the inode, so they are in B-tree format.
157  * Allocate a buffer for the root of the B-tree
158  * and copy the root into it.  The i_extents
159  * field will remain NULL until all of the
160  * extents are read in (when they are needed).
161  */
162 STATIC int
xfs_iformat_btree(struct xfs_inode * ip,struct xfs_dinode * dip,int whichfork)163 xfs_iformat_btree(
164 	struct xfs_inode	*ip,
165 	struct xfs_dinode	*dip,
166 	int			whichfork)
167 {
168 	struct xfs_mount	*mp = ip->i_mount;
169 	xfs_bmdr_block_t	*dfp;
170 	struct xfs_ifork	*ifp;
171 	/* REFERENCED */
172 	int			nrecs;
173 	int			size;
174 	int			level;
175 
176 	ifp = xfs_ifork_ptr(ip, whichfork);
177 	dfp = (xfs_bmdr_block_t *)XFS_DFORK_PTR(dip, whichfork);
178 	size = XFS_BMAP_BROOT_SPACE(mp, dfp);
179 	nrecs = be16_to_cpu(dfp->bb_numrecs);
180 	level = be16_to_cpu(dfp->bb_level);
181 
182 	/*
183 	 * blow out if -- fork has less extents than can fit in
184 	 * fork (fork shouldn't be a btree format), root btree
185 	 * block has more records than can fit into the fork,
186 	 * or the number of extents is greater than the number of
187 	 * blocks.
188 	 */
189 	if (unlikely(ifp->if_nextents <= XFS_IFORK_MAXEXT(ip, whichfork) ||
190 		     nrecs == 0 ||
191 		     XFS_BMDR_SPACE_CALC(nrecs) >
192 					XFS_DFORK_SIZE(dip, mp, whichfork) ||
193 		     ifp->if_nextents > ip->i_nblocks) ||
194 		     level == 0 || level > XFS_BM_MAXLEVELS(mp, whichfork)) {
195 		xfs_warn(mp, "corrupt inode %llu (btree).",
196 					(unsigned long long) ip->i_ino);
197 		xfs_inode_verifier_error(ip, -EFSCORRUPTED,
198 				"xfs_iformat_btree", dfp, size,
199 				__this_address);
200 		return -EFSCORRUPTED;
201 	}
202 
203 	ifp->if_broot_bytes = size;
204 	ifp->if_broot = kmem_alloc(size, KM_NOFS);
205 	ASSERT(ifp->if_broot != NULL);
206 	/*
207 	 * Copy and convert from the on-disk structure
208 	 * to the in-memory structure.
209 	 */
210 	xfs_bmdr_to_bmbt(ip, dfp, XFS_DFORK_SIZE(dip, ip->i_mount, whichfork),
211 			 ifp->if_broot, size);
212 
213 	ifp->if_bytes = 0;
214 	ifp->if_u1.if_root = NULL;
215 	ifp->if_height = 0;
216 	return 0;
217 }
218 
219 int
xfs_iformat_data_fork(struct xfs_inode * ip,struct xfs_dinode * dip)220 xfs_iformat_data_fork(
221 	struct xfs_inode	*ip,
222 	struct xfs_dinode	*dip)
223 {
224 	struct inode		*inode = VFS_I(ip);
225 	int			error;
226 
227 	/*
228 	 * Initialize the extent count early, as the per-format routines may
229 	 * depend on it.
230 	 */
231 	ip->i_df.if_format = dip->di_format;
232 	ip->i_df.if_nextents = xfs_dfork_data_extents(dip);
233 
234 	switch (inode->i_mode & S_IFMT) {
235 	case S_IFIFO:
236 	case S_IFCHR:
237 	case S_IFBLK:
238 	case S_IFSOCK:
239 		ip->i_disk_size = 0;
240 		inode->i_rdev = xfs_to_linux_dev_t(xfs_dinode_get_rdev(dip));
241 		return 0;
242 	case S_IFREG:
243 	case S_IFLNK:
244 	case S_IFDIR:
245 		switch (ip->i_df.if_format) {
246 		case XFS_DINODE_FMT_LOCAL:
247 			error = xfs_iformat_local(ip, dip, XFS_DATA_FORK,
248 					be64_to_cpu(dip->di_size));
249 			if (!error)
250 				error = xfs_ifork_verify_local_data(ip);
251 			return error;
252 		case XFS_DINODE_FMT_EXTENTS:
253 			return xfs_iformat_extents(ip, dip, XFS_DATA_FORK);
254 		case XFS_DINODE_FMT_BTREE:
255 			return xfs_iformat_btree(ip, dip, XFS_DATA_FORK);
256 		default:
257 			xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__,
258 					dip, sizeof(*dip), __this_address);
259 			return -EFSCORRUPTED;
260 		}
261 		break;
262 	default:
263 		xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__, dip,
264 				sizeof(*dip), __this_address);
265 		return -EFSCORRUPTED;
266 	}
267 }
268 
269 static uint16_t
xfs_dfork_attr_shortform_size(struct xfs_dinode * dip)270 xfs_dfork_attr_shortform_size(
271 	struct xfs_dinode		*dip)
272 {
273 	struct xfs_attr_shortform	*atp =
274 		(struct xfs_attr_shortform *)XFS_DFORK_APTR(dip);
275 
276 	return be16_to_cpu(atp->hdr.totsize);
277 }
278 
279 void
xfs_ifork_init_attr(struct xfs_inode * ip,enum xfs_dinode_fmt format,xfs_extnum_t nextents)280 xfs_ifork_init_attr(
281 	struct xfs_inode	*ip,
282 	enum xfs_dinode_fmt	format,
283 	xfs_extnum_t		nextents)
284 {
285 	ip->i_af.if_format = format;
286 	ip->i_af.if_nextents = nextents;
287 }
288 
289 void
xfs_ifork_zap_attr(struct xfs_inode * ip)290 xfs_ifork_zap_attr(
291 	struct xfs_inode	*ip)
292 {
293 	xfs_idestroy_fork(&ip->i_af);
294 	memset(&ip->i_af, 0, sizeof(struct xfs_ifork));
295 	ip->i_af.if_format = XFS_DINODE_FMT_EXTENTS;
296 }
297 
298 int
xfs_iformat_attr_fork(struct xfs_inode * ip,struct xfs_dinode * dip)299 xfs_iformat_attr_fork(
300 	struct xfs_inode	*ip,
301 	struct xfs_dinode	*dip)
302 {
303 	xfs_extnum_t		naextents = xfs_dfork_attr_extents(dip);
304 	int			error = 0;
305 
306 	/*
307 	 * Initialize the extent count early, as the per-format routines may
308 	 * depend on it.
309 	 */
310 	xfs_ifork_init_attr(ip, dip->di_aformat, naextents);
311 
312 	switch (ip->i_af.if_format) {
313 	case XFS_DINODE_FMT_LOCAL:
314 		error = xfs_iformat_local(ip, dip, XFS_ATTR_FORK,
315 				xfs_dfork_attr_shortform_size(dip));
316 		if (!error)
317 			error = xfs_ifork_verify_local_attr(ip);
318 		break;
319 	case XFS_DINODE_FMT_EXTENTS:
320 		error = xfs_iformat_extents(ip, dip, XFS_ATTR_FORK);
321 		break;
322 	case XFS_DINODE_FMT_BTREE:
323 		error = xfs_iformat_btree(ip, dip, XFS_ATTR_FORK);
324 		break;
325 	default:
326 		xfs_inode_verifier_error(ip, error, __func__, dip,
327 				sizeof(*dip), __this_address);
328 		error = -EFSCORRUPTED;
329 		break;
330 	}
331 
332 	if (error)
333 		xfs_ifork_zap_attr(ip);
334 	return error;
335 }
336 
337 /*
338  * Reallocate the space for if_broot based on the number of records
339  * being added or deleted as indicated in rec_diff.  Move the records
340  * and pointers in if_broot to fit the new size.  When shrinking this
341  * will eliminate holes between the records and pointers created by
342  * the caller.  When growing this will create holes to be filled in
343  * by the caller.
344  *
345  * The caller must not request to add more records than would fit in
346  * the on-disk inode root.  If the if_broot is currently NULL, then
347  * if we are adding records, one will be allocated.  The caller must also
348  * not request that the number of records go below zero, although
349  * it can go to zero.
350  *
351  * ip -- the inode whose if_broot area is changing
352  * ext_diff -- the change in the number of records, positive or negative,
353  *	 requested for the if_broot array.
354  */
355 void
xfs_iroot_realloc(xfs_inode_t * ip,int rec_diff,int whichfork)356 xfs_iroot_realloc(
357 	xfs_inode_t		*ip,
358 	int			rec_diff,
359 	int			whichfork)
360 {
361 	struct xfs_mount	*mp = ip->i_mount;
362 	int			cur_max;
363 	struct xfs_ifork	*ifp;
364 	struct xfs_btree_block	*new_broot;
365 	int			new_max;
366 	size_t			new_size;
367 	char			*np;
368 	char			*op;
369 
370 	/*
371 	 * Handle the degenerate case quietly.
372 	 */
373 	if (rec_diff == 0) {
374 		return;
375 	}
376 
377 	ifp = xfs_ifork_ptr(ip, whichfork);
378 	if (rec_diff > 0) {
379 		/*
380 		 * If there wasn't any memory allocated before, just
381 		 * allocate it now and get out.
382 		 */
383 		if (ifp->if_broot_bytes == 0) {
384 			new_size = XFS_BMAP_BROOT_SPACE_CALC(mp, rec_diff);
385 			ifp->if_broot = kmem_alloc(new_size, KM_NOFS);
386 			ifp->if_broot_bytes = (int)new_size;
387 			return;
388 		}
389 
390 		/*
391 		 * If there is already an existing if_broot, then we need
392 		 * to realloc() it and shift the pointers to their new
393 		 * location.  The records don't change location because
394 		 * they are kept butted up against the btree block header.
395 		 */
396 		cur_max = xfs_bmbt_maxrecs(mp, ifp->if_broot_bytes, 0);
397 		new_max = cur_max + rec_diff;
398 		new_size = XFS_BMAP_BROOT_SPACE_CALC(mp, new_max);
399 		ifp->if_broot = krealloc(ifp->if_broot, new_size,
400 					 GFP_NOFS | __GFP_NOFAIL);
401 		op = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1,
402 						     ifp->if_broot_bytes);
403 		np = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1,
404 						     (int)new_size);
405 		ifp->if_broot_bytes = (int)new_size;
406 		ASSERT(XFS_BMAP_BMDR_SPACE(ifp->if_broot) <=
407 			xfs_inode_fork_size(ip, whichfork));
408 		memmove(np, op, cur_max * (uint)sizeof(xfs_fsblock_t));
409 		return;
410 	}
411 
412 	/*
413 	 * rec_diff is less than 0.  In this case, we are shrinking the
414 	 * if_broot buffer.  It must already exist.  If we go to zero
415 	 * records, just get rid of the root and clear the status bit.
416 	 */
417 	ASSERT((ifp->if_broot != NULL) && (ifp->if_broot_bytes > 0));
418 	cur_max = xfs_bmbt_maxrecs(mp, ifp->if_broot_bytes, 0);
419 	new_max = cur_max + rec_diff;
420 	ASSERT(new_max >= 0);
421 	if (new_max > 0)
422 		new_size = XFS_BMAP_BROOT_SPACE_CALC(mp, new_max);
423 	else
424 		new_size = 0;
425 	if (new_size > 0) {
426 		new_broot = kmem_alloc(new_size, KM_NOFS);
427 		/*
428 		 * First copy over the btree block header.
429 		 */
430 		memcpy(new_broot, ifp->if_broot,
431 			XFS_BMBT_BLOCK_LEN(ip->i_mount));
432 	} else {
433 		new_broot = NULL;
434 	}
435 
436 	/*
437 	 * Only copy the records and pointers if there are any.
438 	 */
439 	if (new_max > 0) {
440 		/*
441 		 * First copy the records.
442 		 */
443 		op = (char *)XFS_BMBT_REC_ADDR(mp, ifp->if_broot, 1);
444 		np = (char *)XFS_BMBT_REC_ADDR(mp, new_broot, 1);
445 		memcpy(np, op, new_max * (uint)sizeof(xfs_bmbt_rec_t));
446 
447 		/*
448 		 * Then copy the pointers.
449 		 */
450 		op = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1,
451 						     ifp->if_broot_bytes);
452 		np = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, new_broot, 1,
453 						     (int)new_size);
454 		memcpy(np, op, new_max * (uint)sizeof(xfs_fsblock_t));
455 	}
456 	kmem_free(ifp->if_broot);
457 	ifp->if_broot = new_broot;
458 	ifp->if_broot_bytes = (int)new_size;
459 	if (ifp->if_broot)
460 		ASSERT(XFS_BMAP_BMDR_SPACE(ifp->if_broot) <=
461 			xfs_inode_fork_size(ip, whichfork));
462 	return;
463 }
464 
465 
466 /*
467  * This is called when the amount of space needed for if_data
468  * is increased or decreased.  The change in size is indicated by
469  * the number of bytes that need to be added or deleted in the
470  * byte_diff parameter.
471  *
472  * If the amount of space needed has decreased below the size of the
473  * inline buffer, then switch to using the inline buffer.  Otherwise,
474  * use kmem_realloc() or kmem_alloc() to adjust the size of the buffer
475  * to what is needed.
476  *
477  * ip -- the inode whose if_data area is changing
478  * byte_diff -- the change in the number of bytes, positive or negative,
479  *	 requested for the if_data array.
480  */
481 void
xfs_idata_realloc(struct xfs_inode * ip,int64_t byte_diff,int whichfork)482 xfs_idata_realloc(
483 	struct xfs_inode	*ip,
484 	int64_t			byte_diff,
485 	int			whichfork)
486 {
487 	struct xfs_ifork	*ifp = xfs_ifork_ptr(ip, whichfork);
488 	int64_t			new_size = ifp->if_bytes + byte_diff;
489 
490 	ASSERT(new_size >= 0);
491 	ASSERT(new_size <= xfs_inode_fork_size(ip, whichfork));
492 
493 	if (byte_diff == 0)
494 		return;
495 
496 	if (new_size == 0) {
497 		kmem_free(ifp->if_u1.if_data);
498 		ifp->if_u1.if_data = NULL;
499 		ifp->if_bytes = 0;
500 		return;
501 	}
502 
503 	ifp->if_u1.if_data = krealloc(ifp->if_u1.if_data, new_size,
504 				      GFP_NOFS | __GFP_NOFAIL);
505 	ifp->if_bytes = new_size;
506 }
507 
508 void
xfs_idestroy_fork(struct xfs_ifork * ifp)509 xfs_idestroy_fork(
510 	struct xfs_ifork	*ifp)
511 {
512 	if (ifp->if_broot != NULL) {
513 		kmem_free(ifp->if_broot);
514 		ifp->if_broot = NULL;
515 	}
516 
517 	switch (ifp->if_format) {
518 	case XFS_DINODE_FMT_LOCAL:
519 		kmem_free(ifp->if_u1.if_data);
520 		ifp->if_u1.if_data = NULL;
521 		break;
522 	case XFS_DINODE_FMT_EXTENTS:
523 	case XFS_DINODE_FMT_BTREE:
524 		if (ifp->if_height)
525 			xfs_iext_destroy(ifp);
526 		break;
527 	}
528 }
529 
530 /*
531  * Convert in-core extents to on-disk form
532  *
533  * In the case of the data fork, the in-core and on-disk fork sizes can be
534  * different due to delayed allocation extents. We only copy on-disk extents
535  * here, so callers must always use the physical fork size to determine the
536  * size of the buffer passed to this routine.  We will return the size actually
537  * used.
538  */
539 int
xfs_iextents_copy(struct xfs_inode * ip,struct xfs_bmbt_rec * dp,int whichfork)540 xfs_iextents_copy(
541 	struct xfs_inode	*ip,
542 	struct xfs_bmbt_rec	*dp,
543 	int			whichfork)
544 {
545 	int			state = xfs_bmap_fork_to_state(whichfork);
546 	struct xfs_ifork	*ifp = xfs_ifork_ptr(ip, whichfork);
547 	struct xfs_iext_cursor	icur;
548 	struct xfs_bmbt_irec	rec;
549 	int64_t			copied = 0;
550 
551 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL | XFS_ILOCK_SHARED));
552 	ASSERT(ifp->if_bytes > 0);
553 
554 	for_each_xfs_iext(ifp, &icur, &rec) {
555 		if (isnullstartblock(rec.br_startblock))
556 			continue;
557 		ASSERT(xfs_bmap_validate_extent(ip, whichfork, &rec) == NULL);
558 		xfs_bmbt_disk_set_all(dp, &rec);
559 		trace_xfs_write_extent(ip, &icur, state, _RET_IP_);
560 		copied += sizeof(struct xfs_bmbt_rec);
561 		dp++;
562 	}
563 
564 	ASSERT(copied > 0);
565 	ASSERT(copied <= ifp->if_bytes);
566 	return copied;
567 }
568 
569 /*
570  * Each of the following cases stores data into the same region
571  * of the on-disk inode, so only one of them can be valid at
572  * any given time. While it is possible to have conflicting formats
573  * and log flags, e.g. having XFS_ILOG_?DATA set when the fork is
574  * in EXTENTS format, this can only happen when the fork has
575  * changed formats after being modified but before being flushed.
576  * In these cases, the format always takes precedence, because the
577  * format indicates the current state of the fork.
578  */
579 void
xfs_iflush_fork(struct xfs_inode * ip,struct xfs_dinode * dip,struct xfs_inode_log_item * iip,int whichfork)580 xfs_iflush_fork(
581 	struct xfs_inode	*ip,
582 	struct xfs_dinode	*dip,
583 	struct xfs_inode_log_item *iip,
584 	int			whichfork)
585 {
586 	char			*cp;
587 	struct xfs_ifork	*ifp;
588 	xfs_mount_t		*mp;
589 	static const short	brootflag[2] =
590 		{ XFS_ILOG_DBROOT, XFS_ILOG_ABROOT };
591 	static const short	dataflag[2] =
592 		{ XFS_ILOG_DDATA, XFS_ILOG_ADATA };
593 	static const short	extflag[2] =
594 		{ XFS_ILOG_DEXT, XFS_ILOG_AEXT };
595 
596 	if (!iip)
597 		return;
598 	ifp = xfs_ifork_ptr(ip, whichfork);
599 	/*
600 	 * This can happen if we gave up in iformat in an error path,
601 	 * for the attribute fork.
602 	 */
603 	if (!ifp) {
604 		ASSERT(whichfork == XFS_ATTR_FORK);
605 		return;
606 	}
607 	cp = XFS_DFORK_PTR(dip, whichfork);
608 	mp = ip->i_mount;
609 	switch (ifp->if_format) {
610 	case XFS_DINODE_FMT_LOCAL:
611 		if ((iip->ili_fields & dataflag[whichfork]) &&
612 		    (ifp->if_bytes > 0)) {
613 			ASSERT(ifp->if_u1.if_data != NULL);
614 			ASSERT(ifp->if_bytes <= xfs_inode_fork_size(ip, whichfork));
615 			memcpy(cp, ifp->if_u1.if_data, ifp->if_bytes);
616 		}
617 		break;
618 
619 	case XFS_DINODE_FMT_EXTENTS:
620 		if ((iip->ili_fields & extflag[whichfork]) &&
621 		    (ifp->if_bytes > 0)) {
622 			ASSERT(ifp->if_nextents > 0);
623 			(void)xfs_iextents_copy(ip, (xfs_bmbt_rec_t *)cp,
624 				whichfork);
625 		}
626 		break;
627 
628 	case XFS_DINODE_FMT_BTREE:
629 		if ((iip->ili_fields & brootflag[whichfork]) &&
630 		    (ifp->if_broot_bytes > 0)) {
631 			ASSERT(ifp->if_broot != NULL);
632 			ASSERT(XFS_BMAP_BMDR_SPACE(ifp->if_broot) <=
633 			        xfs_inode_fork_size(ip, whichfork));
634 			xfs_bmbt_to_bmdr(mp, ifp->if_broot, ifp->if_broot_bytes,
635 				(xfs_bmdr_block_t *)cp,
636 				XFS_DFORK_SIZE(dip, mp, whichfork));
637 		}
638 		break;
639 
640 	case XFS_DINODE_FMT_DEV:
641 		if (iip->ili_fields & XFS_ILOG_DEV) {
642 			ASSERT(whichfork == XFS_DATA_FORK);
643 			xfs_dinode_put_rdev(dip,
644 					linux_to_xfs_dev_t(VFS_I(ip)->i_rdev));
645 		}
646 		break;
647 
648 	default:
649 		ASSERT(0);
650 		break;
651 	}
652 }
653 
654 /* Convert bmap state flags to an inode fork. */
655 struct xfs_ifork *
xfs_iext_state_to_fork(struct xfs_inode * ip,int state)656 xfs_iext_state_to_fork(
657 	struct xfs_inode	*ip,
658 	int			state)
659 {
660 	if (state & BMAP_COWFORK)
661 		return ip->i_cowfp;
662 	else if (state & BMAP_ATTRFORK)
663 		return &ip->i_af;
664 	return &ip->i_df;
665 }
666 
667 /*
668  * Initialize an inode's copy-on-write fork.
669  */
670 void
xfs_ifork_init_cow(struct xfs_inode * ip)671 xfs_ifork_init_cow(
672 	struct xfs_inode	*ip)
673 {
674 	if (ip->i_cowfp)
675 		return;
676 
677 	ip->i_cowfp = kmem_cache_zalloc(xfs_ifork_cache,
678 				       GFP_NOFS | __GFP_NOFAIL);
679 	ip->i_cowfp->if_format = XFS_DINODE_FMT_EXTENTS;
680 }
681 
682 /* Verify the inline contents of the data fork of an inode. */
683 int
xfs_ifork_verify_local_data(struct xfs_inode * ip)684 xfs_ifork_verify_local_data(
685 	struct xfs_inode	*ip)
686 {
687 	xfs_failaddr_t		fa = NULL;
688 
689 	switch (VFS_I(ip)->i_mode & S_IFMT) {
690 	case S_IFDIR:
691 		fa = xfs_dir2_sf_verify(ip);
692 		break;
693 	case S_IFLNK:
694 		fa = xfs_symlink_shortform_verify(ip);
695 		break;
696 	default:
697 		break;
698 	}
699 
700 	if (fa) {
701 		xfs_inode_verifier_error(ip, -EFSCORRUPTED, "data fork",
702 				ip->i_df.if_u1.if_data, ip->i_df.if_bytes, fa);
703 		return -EFSCORRUPTED;
704 	}
705 
706 	return 0;
707 }
708 
709 /* Verify the inline contents of the attr fork of an inode. */
710 int
xfs_ifork_verify_local_attr(struct xfs_inode * ip)711 xfs_ifork_verify_local_attr(
712 	struct xfs_inode	*ip)
713 {
714 	struct xfs_ifork	*ifp = &ip->i_af;
715 	xfs_failaddr_t		fa;
716 
717 	if (!xfs_inode_has_attr_fork(ip))
718 		fa = __this_address;
719 	else
720 		fa = xfs_attr_shortform_verify(ip);
721 
722 	if (fa) {
723 		xfs_inode_verifier_error(ip, -EFSCORRUPTED, "attr fork",
724 				ifp->if_u1.if_data, ifp->if_bytes, fa);
725 		return -EFSCORRUPTED;
726 	}
727 
728 	return 0;
729 }
730 
731 int
xfs_iext_count_may_overflow(struct xfs_inode * ip,int whichfork,int nr_to_add)732 xfs_iext_count_may_overflow(
733 	struct xfs_inode	*ip,
734 	int			whichfork,
735 	int			nr_to_add)
736 {
737 	struct xfs_ifork	*ifp = xfs_ifork_ptr(ip, whichfork);
738 	uint64_t		max_exts;
739 	uint64_t		nr_exts;
740 
741 	if (whichfork == XFS_COW_FORK)
742 		return 0;
743 
744 	max_exts = xfs_iext_max_nextents(xfs_inode_has_large_extent_counts(ip),
745 				whichfork);
746 
747 	if (XFS_TEST_ERROR(false, ip->i_mount, XFS_ERRTAG_REDUCE_MAX_IEXTENTS))
748 		max_exts = 10;
749 
750 	nr_exts = ifp->if_nextents + nr_to_add;
751 	if (nr_exts < ifp->if_nextents || nr_exts > max_exts)
752 		return -EFBIG;
753 
754 	return 0;
755 }
756 
757 /*
758  * Upgrade this inode's extent counter fields to be able to handle a potential
759  * increase in the extent count by nr_to_add.  Normally this is the same
760  * quantity that caused xfs_iext_count_may_overflow() to return -EFBIG.
761  */
762 int
xfs_iext_count_upgrade(struct xfs_trans * tp,struct xfs_inode * ip,uint nr_to_add)763 xfs_iext_count_upgrade(
764 	struct xfs_trans	*tp,
765 	struct xfs_inode	*ip,
766 	uint			nr_to_add)
767 {
768 	ASSERT(nr_to_add <= XFS_MAX_EXTCNT_UPGRADE_NR);
769 
770 	if (!xfs_has_large_extent_counts(ip->i_mount) ||
771 	    xfs_inode_has_large_extent_counts(ip) ||
772 	    XFS_TEST_ERROR(false, ip->i_mount, XFS_ERRTAG_REDUCE_MAX_IEXTENTS))
773 		return -EFBIG;
774 
775 	ip->i_diflags2 |= XFS_DIFLAG2_NREXT64;
776 	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
777 
778 	return 0;
779 }
780