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 kmem_zone_t *xfs_ifork_zone;
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, real_size = 0;
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 		real_size = roundup(mem_size, 4);
54 		ifp->if_u1.if_data = kmem_alloc(real_size, KM_NOFS);
55 		memcpy(ifp->if_u1.if_data, data, size);
56 		if (zero_terminate)
57 			ifp->if_u1.if_data[size] = '\0';
58 	} else {
59 		ifp->if_u1.if_data = NULL;
60 	}
61 
62 	ifp->if_bytes = size;
63 }
64 
65 /*
66  * The file is in-lined in the on-disk inode.
67  */
68 STATIC int
xfs_iformat_local(xfs_inode_t * ip,xfs_dinode_t * dip,int whichfork,int size)69 xfs_iformat_local(
70 	xfs_inode_t	*ip,
71 	xfs_dinode_t	*dip,
72 	int		whichfork,
73 	int		size)
74 {
75 	/*
76 	 * If the size is unreasonable, then something
77 	 * is wrong and we just bail out rather than crash in
78 	 * kmem_alloc() or memcpy() below.
79 	 */
80 	if (unlikely(size > XFS_DFORK_SIZE(dip, ip->i_mount, whichfork))) {
81 		xfs_warn(ip->i_mount,
82 	"corrupt inode %Lu (bad size %d for local fork, size = %zd).",
83 			(unsigned long long) ip->i_ino, size,
84 			XFS_DFORK_SIZE(dip, ip->i_mount, whichfork));
85 		xfs_inode_verifier_error(ip, -EFSCORRUPTED,
86 				"xfs_iformat_local", dip, sizeof(*dip),
87 				__this_address);
88 		return -EFSCORRUPTED;
89 	}
90 
91 	xfs_init_local_fork(ip, whichfork, XFS_DFORK_PTR(dip, whichfork), size);
92 	return 0;
93 }
94 
95 /*
96  * The file consists of a set of extents all of which fit into the on-disk
97  * inode.
98  */
99 STATIC int
xfs_iformat_extents(struct xfs_inode * ip,struct xfs_dinode * dip,int whichfork)100 xfs_iformat_extents(
101 	struct xfs_inode	*ip,
102 	struct xfs_dinode	*dip,
103 	int			whichfork)
104 {
105 	struct xfs_mount	*mp = ip->i_mount;
106 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);
107 	int			state = xfs_bmap_fork_to_state(whichfork);
108 	int			nex = XFS_DFORK_NEXTENTS(dip, whichfork);
109 	int			size = nex * sizeof(xfs_bmbt_rec_t);
110 	struct xfs_iext_cursor	icur;
111 	struct xfs_bmbt_rec	*dp;
112 	struct xfs_bmbt_irec	new;
113 	int			i;
114 
115 	/*
116 	 * If the number of extents is unreasonable, then something is wrong and
117 	 * we just bail out rather than crash in kmem_alloc() or memcpy() below.
118 	 */
119 	if (unlikely(size < 0 || size > XFS_DFORK_SIZE(dip, mp, whichfork))) {
120 		xfs_warn(ip->i_mount, "corrupt inode %Lu ((a)extents = %d).",
121 			(unsigned long long) ip->i_ino, nex);
122 		xfs_inode_verifier_error(ip, -EFSCORRUPTED,
123 				"xfs_iformat_extents(1)", dip, sizeof(*dip),
124 				__this_address);
125 		return -EFSCORRUPTED;
126 	}
127 
128 	ifp->if_bytes = 0;
129 	ifp->if_u1.if_root = NULL;
130 	ifp->if_height = 0;
131 	if (size) {
132 		dp = (xfs_bmbt_rec_t *) XFS_DFORK_PTR(dip, whichfork);
133 
134 		xfs_iext_first(ifp, &icur);
135 		for (i = 0; i < nex; i++, dp++) {
136 			xfs_failaddr_t	fa;
137 
138 			xfs_bmbt_disk_get_all(dp, &new);
139 			fa = xfs_bmap_validate_extent(ip, whichfork, &new);
140 			if (fa) {
141 				xfs_inode_verifier_error(ip, -EFSCORRUPTED,
142 						"xfs_iformat_extents(2)",
143 						dp, sizeof(*dp), fa);
144 				return -EFSCORRUPTED;
145 			}
146 
147 			xfs_iext_insert(ip, &icur, &new, state);
148 			trace_xfs_read_extent(ip, &icur, state, _THIS_IP_);
149 			xfs_iext_next(ifp, &icur);
150 		}
151 	}
152 	return 0;
153 }
154 
155 /*
156  * The file has too many extents to fit into
157  * the inode, so they are in B-tree format.
158  * Allocate a buffer for the root of the B-tree
159  * and copy the root into it.  The i_extents
160  * field will remain NULL until all of the
161  * extents are read in (when they are needed).
162  */
163 STATIC int
xfs_iformat_btree(xfs_inode_t * ip,xfs_dinode_t * dip,int whichfork)164 xfs_iformat_btree(
165 	xfs_inode_t		*ip,
166 	xfs_dinode_t		*dip,
167 	int			whichfork)
168 {
169 	struct xfs_mount	*mp = ip->i_mount;
170 	xfs_bmdr_block_t	*dfp;
171 	struct xfs_ifork	*ifp;
172 	/* REFERENCED */
173 	int			nrecs;
174 	int			size;
175 	int			level;
176 
177 	ifp = XFS_IFORK_PTR(ip, whichfork);
178 	dfp = (xfs_bmdr_block_t *)XFS_DFORK_PTR(dip, whichfork);
179 	size = XFS_BMAP_BROOT_SPACE(mp, dfp);
180 	nrecs = be16_to_cpu(dfp->bb_numrecs);
181 	level = be16_to_cpu(dfp->bb_level);
182 
183 	/*
184 	 * blow out if -- fork has less extents than can fit in
185 	 * fork (fork shouldn't be a btree format), root btree
186 	 * block has more records than can fit into the fork,
187 	 * or the number of extents is greater than the number of
188 	 * blocks.
189 	 */
190 	if (unlikely(ifp->if_nextents <= XFS_IFORK_MAXEXT(ip, whichfork) ||
191 		     nrecs == 0 ||
192 		     XFS_BMDR_SPACE_CALC(nrecs) >
193 					XFS_DFORK_SIZE(dip, mp, whichfork) ||
194 		     ifp->if_nextents > ip->i_nblocks) ||
195 		     level == 0 || level > XFS_BM_MAXLEVELS(mp, whichfork)) {
196 		xfs_warn(mp, "corrupt inode %Lu (btree).",
197 					(unsigned long long) ip->i_ino);
198 		xfs_inode_verifier_error(ip, -EFSCORRUPTED,
199 				"xfs_iformat_btree", dfp, size,
200 				__this_address);
201 		return -EFSCORRUPTED;
202 	}
203 
204 	ifp->if_broot_bytes = size;
205 	ifp->if_broot = kmem_alloc(size, KM_NOFS);
206 	ASSERT(ifp->if_broot != NULL);
207 	/*
208 	 * Copy and convert from the on-disk structure
209 	 * to the in-memory structure.
210 	 */
211 	xfs_bmdr_to_bmbt(ip, dfp, XFS_DFORK_SIZE(dip, ip->i_mount, whichfork),
212 			 ifp->if_broot, size);
213 
214 	ifp->if_bytes = 0;
215 	ifp->if_u1.if_root = NULL;
216 	ifp->if_height = 0;
217 	return 0;
218 }
219 
220 int
xfs_iformat_data_fork(struct xfs_inode * ip,struct xfs_dinode * dip)221 xfs_iformat_data_fork(
222 	struct xfs_inode	*ip,
223 	struct xfs_dinode	*dip)
224 {
225 	struct inode		*inode = VFS_I(ip);
226 	int			error;
227 
228 	/*
229 	 * Initialize the extent count early, as the per-format routines may
230 	 * depend on it.
231 	 */
232 	ip->i_df.if_format = dip->di_format;
233 	ip->i_df.if_nextents = be32_to_cpu(dip->di_nextents);
234 
235 	switch (inode->i_mode & S_IFMT) {
236 	case S_IFIFO:
237 	case S_IFCHR:
238 	case S_IFBLK:
239 	case S_IFSOCK:
240 		ip->i_disk_size = 0;
241 		inode->i_rdev = xfs_to_linux_dev_t(xfs_dinode_get_rdev(dip));
242 		return 0;
243 	case S_IFREG:
244 	case S_IFLNK:
245 	case S_IFDIR:
246 		switch (ip->i_df.if_format) {
247 		case XFS_DINODE_FMT_LOCAL:
248 			error = xfs_iformat_local(ip, dip, XFS_DATA_FORK,
249 					be64_to_cpu(dip->di_size));
250 			if (!error)
251 				error = xfs_ifork_verify_local_data(ip);
252 			return error;
253 		case XFS_DINODE_FMT_EXTENTS:
254 			return xfs_iformat_extents(ip, dip, XFS_DATA_FORK);
255 		case XFS_DINODE_FMT_BTREE:
256 			return xfs_iformat_btree(ip, dip, XFS_DATA_FORK);
257 		default:
258 			xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__,
259 					dip, sizeof(*dip), __this_address);
260 			return -EFSCORRUPTED;
261 		}
262 		break;
263 	default:
264 		xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__, dip,
265 				sizeof(*dip), __this_address);
266 		return -EFSCORRUPTED;
267 	}
268 }
269 
270 static uint16_t
xfs_dfork_attr_shortform_size(struct xfs_dinode * dip)271 xfs_dfork_attr_shortform_size(
272 	struct xfs_dinode		*dip)
273 {
274 	struct xfs_attr_shortform	*atp =
275 		(struct xfs_attr_shortform *)XFS_DFORK_APTR(dip);
276 
277 	return be16_to_cpu(atp->hdr.totsize);
278 }
279 
280 struct xfs_ifork *
xfs_ifork_alloc(enum xfs_dinode_fmt format,xfs_extnum_t nextents)281 xfs_ifork_alloc(
282 	enum xfs_dinode_fmt	format,
283 	xfs_extnum_t		nextents)
284 {
285 	struct xfs_ifork	*ifp;
286 
287 	ifp = kmem_cache_zalloc(xfs_ifork_zone, GFP_NOFS | __GFP_NOFAIL);
288 	ifp->if_format = format;
289 	ifp->if_nextents = nextents;
290 	return ifp;
291 }
292 
293 int
xfs_iformat_attr_fork(struct xfs_inode * ip,struct xfs_dinode * dip)294 xfs_iformat_attr_fork(
295 	struct xfs_inode	*ip,
296 	struct xfs_dinode	*dip)
297 {
298 	int			error = 0;
299 
300 	/*
301 	 * Initialize the extent count early, as the per-format routines may
302 	 * depend on it.
303 	 */
304 	ip->i_afp = xfs_ifork_alloc(dip->di_aformat,
305 				be16_to_cpu(dip->di_anextents));
306 
307 	switch (ip->i_afp->if_format) {
308 	case XFS_DINODE_FMT_LOCAL:
309 		error = xfs_iformat_local(ip, dip, XFS_ATTR_FORK,
310 				xfs_dfork_attr_shortform_size(dip));
311 		if (!error)
312 			error = xfs_ifork_verify_local_attr(ip);
313 		break;
314 	case XFS_DINODE_FMT_EXTENTS:
315 		error = xfs_iformat_extents(ip, dip, XFS_ATTR_FORK);
316 		break;
317 	case XFS_DINODE_FMT_BTREE:
318 		error = xfs_iformat_btree(ip, dip, XFS_ATTR_FORK);
319 		break;
320 	default:
321 		xfs_inode_verifier_error(ip, error, __func__, dip,
322 				sizeof(*dip), __this_address);
323 		error = -EFSCORRUPTED;
324 		break;
325 	}
326 
327 	if (error) {
328 		kmem_cache_free(xfs_ifork_zone, ip->i_afp);
329 		ip->i_afp = NULL;
330 	}
331 	return error;
332 }
333 
334 /*
335  * Reallocate the space for if_broot based on the number of records
336  * being added or deleted as indicated in rec_diff.  Move the records
337  * and pointers in if_broot to fit the new size.  When shrinking this
338  * will eliminate holes between the records and pointers created by
339  * the caller.  When growing this will create holes to be filled in
340  * by the caller.
341  *
342  * The caller must not request to add more records than would fit in
343  * the on-disk inode root.  If the if_broot is currently NULL, then
344  * if we are adding records, one will be allocated.  The caller must also
345  * not request that the number of records go below zero, although
346  * it can go to zero.
347  *
348  * ip -- the inode whose if_broot area is changing
349  * ext_diff -- the change in the number of records, positive or negative,
350  *	 requested for the if_broot array.
351  */
352 void
xfs_iroot_realloc(xfs_inode_t * ip,int rec_diff,int whichfork)353 xfs_iroot_realloc(
354 	xfs_inode_t		*ip,
355 	int			rec_diff,
356 	int			whichfork)
357 {
358 	struct xfs_mount	*mp = ip->i_mount;
359 	int			cur_max;
360 	struct xfs_ifork	*ifp;
361 	struct xfs_btree_block	*new_broot;
362 	int			new_max;
363 	size_t			new_size;
364 	char			*np;
365 	char			*op;
366 
367 	/*
368 	 * Handle the degenerate case quietly.
369 	 */
370 	if (rec_diff == 0) {
371 		return;
372 	}
373 
374 	ifp = XFS_IFORK_PTR(ip, whichfork);
375 	if (rec_diff > 0) {
376 		/*
377 		 * If there wasn't any memory allocated before, just
378 		 * allocate it now and get out.
379 		 */
380 		if (ifp->if_broot_bytes == 0) {
381 			new_size = XFS_BMAP_BROOT_SPACE_CALC(mp, rec_diff);
382 			ifp->if_broot = kmem_alloc(new_size, KM_NOFS);
383 			ifp->if_broot_bytes = (int)new_size;
384 			return;
385 		}
386 
387 		/*
388 		 * If there is already an existing if_broot, then we need
389 		 * to realloc() it and shift the pointers to their new
390 		 * location.  The records don't change location because
391 		 * they are kept butted up against the btree block header.
392 		 */
393 		cur_max = xfs_bmbt_maxrecs(mp, ifp->if_broot_bytes, 0);
394 		new_max = cur_max + rec_diff;
395 		new_size = XFS_BMAP_BROOT_SPACE_CALC(mp, new_max);
396 		ifp->if_broot = krealloc(ifp->if_broot, new_size,
397 					 GFP_NOFS | __GFP_NOFAIL);
398 		op = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1,
399 						     ifp->if_broot_bytes);
400 		np = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1,
401 						     (int)new_size);
402 		ifp->if_broot_bytes = (int)new_size;
403 		ASSERT(XFS_BMAP_BMDR_SPACE(ifp->if_broot) <=
404 			XFS_IFORK_SIZE(ip, whichfork));
405 		memmove(np, op, cur_max * (uint)sizeof(xfs_fsblock_t));
406 		return;
407 	}
408 
409 	/*
410 	 * rec_diff is less than 0.  In this case, we are shrinking the
411 	 * if_broot buffer.  It must already exist.  If we go to zero
412 	 * records, just get rid of the root and clear the status bit.
413 	 */
414 	ASSERT((ifp->if_broot != NULL) && (ifp->if_broot_bytes > 0));
415 	cur_max = xfs_bmbt_maxrecs(mp, ifp->if_broot_bytes, 0);
416 	new_max = cur_max + rec_diff;
417 	ASSERT(new_max >= 0);
418 	if (new_max > 0)
419 		new_size = XFS_BMAP_BROOT_SPACE_CALC(mp, new_max);
420 	else
421 		new_size = 0;
422 	if (new_size > 0) {
423 		new_broot = kmem_alloc(new_size, KM_NOFS);
424 		/*
425 		 * First copy over the btree block header.
426 		 */
427 		memcpy(new_broot, ifp->if_broot,
428 			XFS_BMBT_BLOCK_LEN(ip->i_mount));
429 	} else {
430 		new_broot = NULL;
431 	}
432 
433 	/*
434 	 * Only copy the records and pointers if there are any.
435 	 */
436 	if (new_max > 0) {
437 		/*
438 		 * First copy the records.
439 		 */
440 		op = (char *)XFS_BMBT_REC_ADDR(mp, ifp->if_broot, 1);
441 		np = (char *)XFS_BMBT_REC_ADDR(mp, new_broot, 1);
442 		memcpy(np, op, new_max * (uint)sizeof(xfs_bmbt_rec_t));
443 
444 		/*
445 		 * Then copy the pointers.
446 		 */
447 		op = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1,
448 						     ifp->if_broot_bytes);
449 		np = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, new_broot, 1,
450 						     (int)new_size);
451 		memcpy(np, op, new_max * (uint)sizeof(xfs_fsblock_t));
452 	}
453 	kmem_free(ifp->if_broot);
454 	ifp->if_broot = new_broot;
455 	ifp->if_broot_bytes = (int)new_size;
456 	if (ifp->if_broot)
457 		ASSERT(XFS_BMAP_BMDR_SPACE(ifp->if_broot) <=
458 			XFS_IFORK_SIZE(ip, whichfork));
459 	return;
460 }
461 
462 
463 /*
464  * This is called when the amount of space needed for if_data
465  * is increased or decreased.  The change in size is indicated by
466  * the number of bytes that need to be added or deleted in the
467  * byte_diff parameter.
468  *
469  * If the amount of space needed has decreased below the size of the
470  * inline buffer, then switch to using the inline buffer.  Otherwise,
471  * use kmem_realloc() or kmem_alloc() to adjust the size of the buffer
472  * to what is needed.
473  *
474  * ip -- the inode whose if_data area is changing
475  * byte_diff -- the change in the number of bytes, positive or negative,
476  *	 requested for the if_data array.
477  */
478 void
xfs_idata_realloc(struct xfs_inode * ip,int64_t byte_diff,int whichfork)479 xfs_idata_realloc(
480 	struct xfs_inode	*ip,
481 	int64_t			byte_diff,
482 	int			whichfork)
483 {
484 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);
485 	int64_t			new_size = ifp->if_bytes + byte_diff;
486 
487 	ASSERT(new_size >= 0);
488 	ASSERT(new_size <= XFS_IFORK_SIZE(ip, whichfork));
489 
490 	if (byte_diff == 0)
491 		return;
492 
493 	if (new_size == 0) {
494 		kmem_free(ifp->if_u1.if_data);
495 		ifp->if_u1.if_data = NULL;
496 		ifp->if_bytes = 0;
497 		return;
498 	}
499 
500 	/*
501 	 * For inline data, the underlying buffer must be a multiple of 4 bytes
502 	 * in size so that it can be logged and stay on word boundaries.
503 	 * We enforce that here.
504 	 */
505 	ifp->if_u1.if_data = krealloc(ifp->if_u1.if_data, roundup(new_size, 4),
506 				      GFP_NOFS | __GFP_NOFAIL);
507 	ifp->if_bytes = new_size;
508 }
509 
510 void
xfs_idestroy_fork(struct xfs_ifork * ifp)511 xfs_idestroy_fork(
512 	struct xfs_ifork	*ifp)
513 {
514 	if (ifp->if_broot != NULL) {
515 		kmem_free(ifp->if_broot);
516 		ifp->if_broot = NULL;
517 	}
518 
519 	switch (ifp->if_format) {
520 	case XFS_DINODE_FMT_LOCAL:
521 		kmem_free(ifp->if_u1.if_data);
522 		ifp->if_u1.if_data = NULL;
523 		break;
524 	case XFS_DINODE_FMT_EXTENTS:
525 	case XFS_DINODE_FMT_BTREE:
526 		if (ifp->if_height)
527 			xfs_iext_destroy(ifp);
528 		break;
529 	}
530 }
531 
532 /*
533  * Convert in-core extents to on-disk form
534  *
535  * In the case of the data fork, the in-core and on-disk fork sizes can be
536  * different due to delayed allocation extents. We only copy on-disk extents
537  * here, so callers must always use the physical fork size to determine the
538  * size of the buffer passed to this routine.  We will return the size actually
539  * used.
540  */
541 int
xfs_iextents_copy(struct xfs_inode * ip,struct xfs_bmbt_rec * dp,int whichfork)542 xfs_iextents_copy(
543 	struct xfs_inode	*ip,
544 	struct xfs_bmbt_rec	*dp,
545 	int			whichfork)
546 {
547 	int			state = xfs_bmap_fork_to_state(whichfork);
548 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);
549 	struct xfs_iext_cursor	icur;
550 	struct xfs_bmbt_irec	rec;
551 	int64_t			copied = 0;
552 
553 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL | XFS_ILOCK_SHARED));
554 	ASSERT(ifp->if_bytes > 0);
555 
556 	for_each_xfs_iext(ifp, &icur, &rec) {
557 		if (isnullstartblock(rec.br_startblock))
558 			continue;
559 		ASSERT(xfs_bmap_validate_extent(ip, whichfork, &rec) == NULL);
560 		xfs_bmbt_disk_set_all(dp, &rec);
561 		trace_xfs_write_extent(ip, &icur, state, _RET_IP_);
562 		copied += sizeof(struct xfs_bmbt_rec);
563 		dp++;
564 	}
565 
566 	ASSERT(copied > 0);
567 	ASSERT(copied <= ifp->if_bytes);
568 	return copied;
569 }
570 
571 /*
572  * Each of the following cases stores data into the same region
573  * of the on-disk inode, so only one of them can be valid at
574  * any given time. While it is possible to have conflicting formats
575  * and log flags, e.g. having XFS_ILOG_?DATA set when the fork is
576  * in EXTENTS format, this can only happen when the fork has
577  * changed formats after being modified but before being flushed.
578  * In these cases, the format always takes precedence, because the
579  * format indicates the current state of the fork.
580  */
581 void
xfs_iflush_fork(xfs_inode_t * ip,xfs_dinode_t * dip,struct xfs_inode_log_item * iip,int whichfork)582 xfs_iflush_fork(
583 	xfs_inode_t		*ip,
584 	xfs_dinode_t		*dip,
585 	struct xfs_inode_log_item *iip,
586 	int			whichfork)
587 {
588 	char			*cp;
589 	struct xfs_ifork	*ifp;
590 	xfs_mount_t		*mp;
591 	static const short	brootflag[2] =
592 		{ XFS_ILOG_DBROOT, XFS_ILOG_ABROOT };
593 	static const short	dataflag[2] =
594 		{ XFS_ILOG_DDATA, XFS_ILOG_ADATA };
595 	static const short	extflag[2] =
596 		{ XFS_ILOG_DEXT, XFS_ILOG_AEXT };
597 
598 	if (!iip)
599 		return;
600 	ifp = XFS_IFORK_PTR(ip, whichfork);
601 	/*
602 	 * This can happen if we gave up in iformat in an error path,
603 	 * for the attribute fork.
604 	 */
605 	if (!ifp) {
606 		ASSERT(whichfork == XFS_ATTR_FORK);
607 		return;
608 	}
609 	cp = XFS_DFORK_PTR(dip, whichfork);
610 	mp = ip->i_mount;
611 	switch (ifp->if_format) {
612 	case XFS_DINODE_FMT_LOCAL:
613 		if ((iip->ili_fields & dataflag[whichfork]) &&
614 		    (ifp->if_bytes > 0)) {
615 			ASSERT(ifp->if_u1.if_data != NULL);
616 			ASSERT(ifp->if_bytes <= XFS_IFORK_SIZE(ip, whichfork));
617 			memcpy(cp, ifp->if_u1.if_data, ifp->if_bytes);
618 		}
619 		break;
620 
621 	case XFS_DINODE_FMT_EXTENTS:
622 		if ((iip->ili_fields & extflag[whichfork]) &&
623 		    (ifp->if_bytes > 0)) {
624 			ASSERT(ifp->if_nextents > 0);
625 			(void)xfs_iextents_copy(ip, (xfs_bmbt_rec_t *)cp,
626 				whichfork);
627 		}
628 		break;
629 
630 	case XFS_DINODE_FMT_BTREE:
631 		if ((iip->ili_fields & brootflag[whichfork]) &&
632 		    (ifp->if_broot_bytes > 0)) {
633 			ASSERT(ifp->if_broot != NULL);
634 			ASSERT(XFS_BMAP_BMDR_SPACE(ifp->if_broot) <=
635 			        XFS_IFORK_SIZE(ip, whichfork));
636 			xfs_bmbt_to_bmdr(mp, ifp->if_broot, ifp->if_broot_bytes,
637 				(xfs_bmdr_block_t *)cp,
638 				XFS_DFORK_SIZE(dip, mp, whichfork));
639 		}
640 		break;
641 
642 	case XFS_DINODE_FMT_DEV:
643 		if (iip->ili_fields & XFS_ILOG_DEV) {
644 			ASSERT(whichfork == XFS_DATA_FORK);
645 			xfs_dinode_put_rdev(dip,
646 					linux_to_xfs_dev_t(VFS_I(ip)->i_rdev));
647 		}
648 		break;
649 
650 	default:
651 		ASSERT(0);
652 		break;
653 	}
654 }
655 
656 /* Convert bmap state flags to an inode fork. */
657 struct xfs_ifork *
xfs_iext_state_to_fork(struct xfs_inode * ip,int state)658 xfs_iext_state_to_fork(
659 	struct xfs_inode	*ip,
660 	int			state)
661 {
662 	if (state & BMAP_COWFORK)
663 		return ip->i_cowfp;
664 	else if (state & BMAP_ATTRFORK)
665 		return ip->i_afp;
666 	return &ip->i_df;
667 }
668 
669 /*
670  * Initialize an inode's copy-on-write fork.
671  */
672 void
xfs_ifork_init_cow(struct xfs_inode * ip)673 xfs_ifork_init_cow(
674 	struct xfs_inode	*ip)
675 {
676 	if (ip->i_cowfp)
677 		return;
678 
679 	ip->i_cowfp = kmem_cache_zalloc(xfs_ifork_zone,
680 				       GFP_NOFS | __GFP_NOFAIL);
681 	ip->i_cowfp->if_format = XFS_DINODE_FMT_EXTENTS;
682 }
683 
684 /* Verify the inline contents of the data fork of an inode. */
685 int
xfs_ifork_verify_local_data(struct xfs_inode * ip)686 xfs_ifork_verify_local_data(
687 	struct xfs_inode	*ip)
688 {
689 	xfs_failaddr_t		fa = NULL;
690 
691 	switch (VFS_I(ip)->i_mode & S_IFMT) {
692 	case S_IFDIR:
693 		fa = xfs_dir2_sf_verify(ip);
694 		break;
695 	case S_IFLNK:
696 		fa = xfs_symlink_shortform_verify(ip);
697 		break;
698 	default:
699 		break;
700 	}
701 
702 	if (fa) {
703 		xfs_inode_verifier_error(ip, -EFSCORRUPTED, "data fork",
704 				ip->i_df.if_u1.if_data, ip->i_df.if_bytes, fa);
705 		return -EFSCORRUPTED;
706 	}
707 
708 	return 0;
709 }
710 
711 /* Verify the inline contents of the attr fork of an inode. */
712 int
xfs_ifork_verify_local_attr(struct xfs_inode * ip)713 xfs_ifork_verify_local_attr(
714 	struct xfs_inode	*ip)
715 {
716 	struct xfs_ifork	*ifp = ip->i_afp;
717 	xfs_failaddr_t		fa;
718 
719 	if (!ifp)
720 		fa = __this_address;
721 	else
722 		fa = xfs_attr_shortform_verify(ip);
723 
724 	if (fa) {
725 		xfs_inode_verifier_error(ip, -EFSCORRUPTED, "attr fork",
726 				ifp ? ifp->if_u1.if_data : NULL,
727 				ifp ? ifp->if_bytes : 0, fa);
728 		return -EFSCORRUPTED;
729 	}
730 
731 	return 0;
732 }
733 
734 int
xfs_iext_count_may_overflow(struct xfs_inode * ip,int whichfork,int nr_to_add)735 xfs_iext_count_may_overflow(
736 	struct xfs_inode	*ip,
737 	int			whichfork,
738 	int			nr_to_add)
739 {
740 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);
741 	uint64_t		max_exts;
742 	uint64_t		nr_exts;
743 
744 	if (whichfork == XFS_COW_FORK)
745 		return 0;
746 
747 	max_exts = (whichfork == XFS_ATTR_FORK) ? MAXAEXTNUM : MAXEXTNUM;
748 
749 	if (XFS_TEST_ERROR(false, ip->i_mount, XFS_ERRTAG_REDUCE_MAX_IEXTENTS))
750 		max_exts = 10;
751 
752 	nr_exts = ifp->if_nextents + nr_to_add;
753 	if (nr_exts < ifp->if_nextents || nr_exts > max_exts)
754 		return -EFBIG;
755 
756 	return 0;
757 }
758