xref: /openbmc/linux/fs/xfs/libxfs/xfs_attr_leaf.c (revision 40ddb537)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
4  * Copyright (c) 2013 Red Hat, Inc.
5  * All Rights Reserved.
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_sb.h"
14 #include "xfs_mount.h"
15 #include "xfs_da_format.h"
16 #include "xfs_da_btree.h"
17 #include "xfs_inode.h"
18 #include "xfs_trans.h"
19 #include "xfs_bmap_btree.h"
20 #include "xfs_bmap.h"
21 #include "xfs_attr_sf.h"
22 #include "xfs_attr_remote.h"
23 #include "xfs_attr.h"
24 #include "xfs_attr_leaf.h"
25 #include "xfs_error.h"
26 #include "xfs_trace.h"
27 #include "xfs_buf_item.h"
28 #include "xfs_dir2.h"
29 #include "xfs_log.h"
30 
31 
32 /*
33  * xfs_attr_leaf.c
34  *
35  * Routines to implement leaf blocks of attributes as Btrees of hashed names.
36  */
37 
38 /*========================================================================
39  * Function prototypes for the kernel.
40  *========================================================================*/
41 
42 /*
43  * Routines used for growing the Btree.
44  */
45 STATIC int xfs_attr3_leaf_create(struct xfs_da_args *args,
46 				 xfs_dablk_t which_block, struct xfs_buf **bpp);
47 STATIC int xfs_attr3_leaf_add_work(struct xfs_buf *leaf_buffer,
48 				   struct xfs_attr3_icleaf_hdr *ichdr,
49 				   struct xfs_da_args *args, int freemap_index);
50 STATIC void xfs_attr3_leaf_compact(struct xfs_da_args *args,
51 				   struct xfs_attr3_icleaf_hdr *ichdr,
52 				   struct xfs_buf *leaf_buffer);
53 STATIC void xfs_attr3_leaf_rebalance(xfs_da_state_t *state,
54 						   xfs_da_state_blk_t *blk1,
55 						   xfs_da_state_blk_t *blk2);
56 STATIC int xfs_attr3_leaf_figure_balance(xfs_da_state_t *state,
57 			xfs_da_state_blk_t *leaf_blk_1,
58 			struct xfs_attr3_icleaf_hdr *ichdr1,
59 			xfs_da_state_blk_t *leaf_blk_2,
60 			struct xfs_attr3_icleaf_hdr *ichdr2,
61 			int *number_entries_in_blk1,
62 			int *number_usedbytes_in_blk1);
63 
64 /*
65  * Utility routines.
66  */
67 STATIC void xfs_attr3_leaf_moveents(struct xfs_da_args *args,
68 			struct xfs_attr_leafblock *src_leaf,
69 			struct xfs_attr3_icleaf_hdr *src_ichdr, int src_start,
70 			struct xfs_attr_leafblock *dst_leaf,
71 			struct xfs_attr3_icleaf_hdr *dst_ichdr, int dst_start,
72 			int move_count);
73 STATIC int xfs_attr_leaf_entsize(xfs_attr_leafblock_t *leaf, int index);
74 
75 /*
76  * attr3 block 'firstused' conversion helpers.
77  *
78  * firstused refers to the offset of the first used byte of the nameval region
79  * of an attr leaf block. The region starts at the tail of the block and expands
80  * backwards towards the middle. As such, firstused is initialized to the block
81  * size for an empty leaf block and is reduced from there.
82  *
83  * The attr3 block size is pegged to the fsb size and the maximum fsb is 64k.
84  * The in-core firstused field is 32-bit and thus supports the maximum fsb size.
85  * The on-disk field is only 16-bit, however, and overflows at 64k. Since this
86  * only occurs at exactly 64k, we use zero as a magic on-disk value to represent
87  * the attr block size. The following helpers manage the conversion between the
88  * in-core and on-disk formats.
89  */
90 
91 static void
92 xfs_attr3_leaf_firstused_from_disk(
93 	struct xfs_da_geometry		*geo,
94 	struct xfs_attr3_icleaf_hdr	*to,
95 	struct xfs_attr_leafblock	*from)
96 {
97 	struct xfs_attr3_leaf_hdr	*hdr3;
98 
99 	if (from->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC)) {
100 		hdr3 = (struct xfs_attr3_leaf_hdr *) from;
101 		to->firstused = be16_to_cpu(hdr3->firstused);
102 	} else {
103 		to->firstused = be16_to_cpu(from->hdr.firstused);
104 	}
105 
106 	/*
107 	 * Convert from the magic fsb size value to actual blocksize. This
108 	 * should only occur for empty blocks when the block size overflows
109 	 * 16-bits.
110 	 */
111 	if (to->firstused == XFS_ATTR3_LEAF_NULLOFF) {
112 		ASSERT(!to->count && !to->usedbytes);
113 		ASSERT(geo->blksize > USHRT_MAX);
114 		to->firstused = geo->blksize;
115 	}
116 }
117 
118 static void
119 xfs_attr3_leaf_firstused_to_disk(
120 	struct xfs_da_geometry		*geo,
121 	struct xfs_attr_leafblock	*to,
122 	struct xfs_attr3_icleaf_hdr	*from)
123 {
124 	struct xfs_attr3_leaf_hdr	*hdr3;
125 	uint32_t			firstused;
126 
127 	/* magic value should only be seen on disk */
128 	ASSERT(from->firstused != XFS_ATTR3_LEAF_NULLOFF);
129 
130 	/*
131 	 * Scale down the 32-bit in-core firstused value to the 16-bit on-disk
132 	 * value. This only overflows at the max supported value of 64k. Use the
133 	 * magic on-disk value to represent block size in this case.
134 	 */
135 	firstused = from->firstused;
136 	if (firstused > USHRT_MAX) {
137 		ASSERT(from->firstused == geo->blksize);
138 		firstused = XFS_ATTR3_LEAF_NULLOFF;
139 	}
140 
141 	if (from->magic == XFS_ATTR3_LEAF_MAGIC) {
142 		hdr3 = (struct xfs_attr3_leaf_hdr *) to;
143 		hdr3->firstused = cpu_to_be16(firstused);
144 	} else {
145 		to->hdr.firstused = cpu_to_be16(firstused);
146 	}
147 }
148 
149 void
150 xfs_attr3_leaf_hdr_from_disk(
151 	struct xfs_da_geometry		*geo,
152 	struct xfs_attr3_icleaf_hdr	*to,
153 	struct xfs_attr_leafblock	*from)
154 {
155 	int	i;
156 
157 	ASSERT(from->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC) ||
158 	       from->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC));
159 
160 	if (from->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC)) {
161 		struct xfs_attr3_leaf_hdr *hdr3 = (struct xfs_attr3_leaf_hdr *)from;
162 
163 		to->forw = be32_to_cpu(hdr3->info.hdr.forw);
164 		to->back = be32_to_cpu(hdr3->info.hdr.back);
165 		to->magic = be16_to_cpu(hdr3->info.hdr.magic);
166 		to->count = be16_to_cpu(hdr3->count);
167 		to->usedbytes = be16_to_cpu(hdr3->usedbytes);
168 		xfs_attr3_leaf_firstused_from_disk(geo, to, from);
169 		to->holes = hdr3->holes;
170 
171 		for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
172 			to->freemap[i].base = be16_to_cpu(hdr3->freemap[i].base);
173 			to->freemap[i].size = be16_to_cpu(hdr3->freemap[i].size);
174 		}
175 		return;
176 	}
177 	to->forw = be32_to_cpu(from->hdr.info.forw);
178 	to->back = be32_to_cpu(from->hdr.info.back);
179 	to->magic = be16_to_cpu(from->hdr.info.magic);
180 	to->count = be16_to_cpu(from->hdr.count);
181 	to->usedbytes = be16_to_cpu(from->hdr.usedbytes);
182 	xfs_attr3_leaf_firstused_from_disk(geo, to, from);
183 	to->holes = from->hdr.holes;
184 
185 	for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
186 		to->freemap[i].base = be16_to_cpu(from->hdr.freemap[i].base);
187 		to->freemap[i].size = be16_to_cpu(from->hdr.freemap[i].size);
188 	}
189 }
190 
191 void
192 xfs_attr3_leaf_hdr_to_disk(
193 	struct xfs_da_geometry		*geo,
194 	struct xfs_attr_leafblock	*to,
195 	struct xfs_attr3_icleaf_hdr	*from)
196 {
197 	int				i;
198 
199 	ASSERT(from->magic == XFS_ATTR_LEAF_MAGIC ||
200 	       from->magic == XFS_ATTR3_LEAF_MAGIC);
201 
202 	if (from->magic == XFS_ATTR3_LEAF_MAGIC) {
203 		struct xfs_attr3_leaf_hdr *hdr3 = (struct xfs_attr3_leaf_hdr *)to;
204 
205 		hdr3->info.hdr.forw = cpu_to_be32(from->forw);
206 		hdr3->info.hdr.back = cpu_to_be32(from->back);
207 		hdr3->info.hdr.magic = cpu_to_be16(from->magic);
208 		hdr3->count = cpu_to_be16(from->count);
209 		hdr3->usedbytes = cpu_to_be16(from->usedbytes);
210 		xfs_attr3_leaf_firstused_to_disk(geo, to, from);
211 		hdr3->holes = from->holes;
212 		hdr3->pad1 = 0;
213 
214 		for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
215 			hdr3->freemap[i].base = cpu_to_be16(from->freemap[i].base);
216 			hdr3->freemap[i].size = cpu_to_be16(from->freemap[i].size);
217 		}
218 		return;
219 	}
220 	to->hdr.info.forw = cpu_to_be32(from->forw);
221 	to->hdr.info.back = cpu_to_be32(from->back);
222 	to->hdr.info.magic = cpu_to_be16(from->magic);
223 	to->hdr.count = cpu_to_be16(from->count);
224 	to->hdr.usedbytes = cpu_to_be16(from->usedbytes);
225 	xfs_attr3_leaf_firstused_to_disk(geo, to, from);
226 	to->hdr.holes = from->holes;
227 	to->hdr.pad1 = 0;
228 
229 	for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
230 		to->hdr.freemap[i].base = cpu_to_be16(from->freemap[i].base);
231 		to->hdr.freemap[i].size = cpu_to_be16(from->freemap[i].size);
232 	}
233 }
234 
235 static xfs_failaddr_t
236 xfs_attr3_leaf_verify_entry(
237 	struct xfs_mount			*mp,
238 	char					*buf_end,
239 	struct xfs_attr_leafblock		*leaf,
240 	struct xfs_attr3_icleaf_hdr		*leafhdr,
241 	struct xfs_attr_leaf_entry		*ent,
242 	int					idx,
243 	__u32					*last_hashval)
244 {
245 	struct xfs_attr_leaf_name_local		*lentry;
246 	struct xfs_attr_leaf_name_remote	*rentry;
247 	char					*name_end;
248 	unsigned int				nameidx;
249 	unsigned int				namesize;
250 	__u32					hashval;
251 
252 	/* hash order check */
253 	hashval = be32_to_cpu(ent->hashval);
254 	if (hashval < *last_hashval)
255 		return __this_address;
256 	*last_hashval = hashval;
257 
258 	nameidx = be16_to_cpu(ent->nameidx);
259 	if (nameidx < leafhdr->firstused || nameidx >= mp->m_attr_geo->blksize)
260 		return __this_address;
261 
262 	/*
263 	 * Check the name information.  The namelen fields are u8 so we can't
264 	 * possibly exceed the maximum name length of 255 bytes.
265 	 */
266 	if (ent->flags & XFS_ATTR_LOCAL) {
267 		lentry = xfs_attr3_leaf_name_local(leaf, idx);
268 		namesize = xfs_attr_leaf_entsize_local(lentry->namelen,
269 				be16_to_cpu(lentry->valuelen));
270 		name_end = (char *)lentry + namesize;
271 		if (lentry->namelen == 0)
272 			return __this_address;
273 	} else {
274 		rentry = xfs_attr3_leaf_name_remote(leaf, idx);
275 		namesize = xfs_attr_leaf_entsize_remote(rentry->namelen);
276 		name_end = (char *)rentry + namesize;
277 		if (rentry->namelen == 0)
278 			return __this_address;
279 		if (!(ent->flags & XFS_ATTR_INCOMPLETE) &&
280 		    rentry->valueblk == 0)
281 			return __this_address;
282 	}
283 
284 	if (name_end > buf_end)
285 		return __this_address;
286 
287 	return NULL;
288 }
289 
290 static xfs_failaddr_t
291 xfs_attr3_leaf_verify(
292 	struct xfs_buf			*bp)
293 {
294 	struct xfs_attr3_icleaf_hdr	ichdr;
295 	struct xfs_mount		*mp = bp->b_mount;
296 	struct xfs_attr_leafblock	*leaf = bp->b_addr;
297 	struct xfs_attr_leaf_entry	*entries;
298 	struct xfs_attr_leaf_entry	*ent;
299 	char				*buf_end;
300 	uint32_t			end;	/* must be 32bit - see below */
301 	__u32				last_hashval = 0;
302 	int				i;
303 	xfs_failaddr_t			fa;
304 
305 	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf);
306 
307 	fa = xfs_da3_blkinfo_verify(bp, bp->b_addr);
308 	if (fa)
309 		return fa;
310 
311 	/*
312 	 * firstused is the block offset of the first name info structure.
313 	 * Make sure it doesn't go off the block or crash into the header.
314 	 */
315 	if (ichdr.firstused > mp->m_attr_geo->blksize)
316 		return __this_address;
317 	if (ichdr.firstused < xfs_attr3_leaf_hdr_size(leaf))
318 		return __this_address;
319 
320 	/* Make sure the entries array doesn't crash into the name info. */
321 	entries = xfs_attr3_leaf_entryp(bp->b_addr);
322 	if ((char *)&entries[ichdr.count] >
323 	    (char *)bp->b_addr + ichdr.firstused)
324 		return __this_address;
325 
326 	/*
327 	 * NOTE: This verifier historically failed empty leaf buffers because
328 	 * we expect the fork to be in another format. Empty attr fork format
329 	 * conversions are possible during xattr set, however, and format
330 	 * conversion is not atomic with the xattr set that triggers it. We
331 	 * cannot assume leaf blocks are non-empty until that is addressed.
332 	*/
333 	buf_end = (char *)bp->b_addr + mp->m_attr_geo->blksize;
334 	for (i = 0, ent = entries; i < ichdr.count; ent++, i++) {
335 		fa = xfs_attr3_leaf_verify_entry(mp, buf_end, leaf, &ichdr,
336 				ent, i, &last_hashval);
337 		if (fa)
338 			return fa;
339 	}
340 
341 	/*
342 	 * Quickly check the freemap information.  Attribute data has to be
343 	 * aligned to 4-byte boundaries, and likewise for the free space.
344 	 *
345 	 * Note that for 64k block size filesystems, the freemap entries cannot
346 	 * overflow as they are only be16 fields. However, when checking end
347 	 * pointer of the freemap, we have to be careful to detect overflows and
348 	 * so use uint32_t for those checks.
349 	 */
350 	for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
351 		if (ichdr.freemap[i].base > mp->m_attr_geo->blksize)
352 			return __this_address;
353 		if (ichdr.freemap[i].base & 0x3)
354 			return __this_address;
355 		if (ichdr.freemap[i].size > mp->m_attr_geo->blksize)
356 			return __this_address;
357 		if (ichdr.freemap[i].size & 0x3)
358 			return __this_address;
359 
360 		/* be care of 16 bit overflows here */
361 		end = (uint32_t)ichdr.freemap[i].base + ichdr.freemap[i].size;
362 		if (end < ichdr.freemap[i].base)
363 			return __this_address;
364 		if (end > mp->m_attr_geo->blksize)
365 			return __this_address;
366 	}
367 
368 	return NULL;
369 }
370 
371 static void
372 xfs_attr3_leaf_write_verify(
373 	struct xfs_buf	*bp)
374 {
375 	struct xfs_mount	*mp = bp->b_mount;
376 	struct xfs_buf_log_item	*bip = bp->b_log_item;
377 	struct xfs_attr3_leaf_hdr *hdr3 = bp->b_addr;
378 	xfs_failaddr_t		fa;
379 
380 	fa = xfs_attr3_leaf_verify(bp);
381 	if (fa) {
382 		xfs_verifier_error(bp, -EFSCORRUPTED, fa);
383 		return;
384 	}
385 
386 	if (!xfs_sb_version_hascrc(&mp->m_sb))
387 		return;
388 
389 	if (bip)
390 		hdr3->info.lsn = cpu_to_be64(bip->bli_item.li_lsn);
391 
392 	xfs_buf_update_cksum(bp, XFS_ATTR3_LEAF_CRC_OFF);
393 }
394 
395 /*
396  * leaf/node format detection on trees is sketchy, so a node read can be done on
397  * leaf level blocks when detection identifies the tree as a node format tree
398  * incorrectly. In this case, we need to swap the verifier to match the correct
399  * format of the block being read.
400  */
401 static void
402 xfs_attr3_leaf_read_verify(
403 	struct xfs_buf		*bp)
404 {
405 	struct xfs_mount	*mp = bp->b_mount;
406 	xfs_failaddr_t		fa;
407 
408 	if (xfs_sb_version_hascrc(&mp->m_sb) &&
409 	     !xfs_buf_verify_cksum(bp, XFS_ATTR3_LEAF_CRC_OFF))
410 		xfs_verifier_error(bp, -EFSBADCRC, __this_address);
411 	else {
412 		fa = xfs_attr3_leaf_verify(bp);
413 		if (fa)
414 			xfs_verifier_error(bp, -EFSCORRUPTED, fa);
415 	}
416 }
417 
418 const struct xfs_buf_ops xfs_attr3_leaf_buf_ops = {
419 	.name = "xfs_attr3_leaf",
420 	.magic16 = { cpu_to_be16(XFS_ATTR_LEAF_MAGIC),
421 		     cpu_to_be16(XFS_ATTR3_LEAF_MAGIC) },
422 	.verify_read = xfs_attr3_leaf_read_verify,
423 	.verify_write = xfs_attr3_leaf_write_verify,
424 	.verify_struct = xfs_attr3_leaf_verify,
425 };
426 
427 int
428 xfs_attr3_leaf_read(
429 	struct xfs_trans	*tp,
430 	struct xfs_inode	*dp,
431 	xfs_dablk_t		bno,
432 	struct xfs_buf		**bpp)
433 {
434 	int			err;
435 
436 	err = xfs_da_read_buf(tp, dp, bno, 0, bpp, XFS_ATTR_FORK,
437 			&xfs_attr3_leaf_buf_ops);
438 	if (!err && tp && *bpp)
439 		xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_ATTR_LEAF_BUF);
440 	return err;
441 }
442 
443 /*========================================================================
444  * Namespace helper routines
445  *========================================================================*/
446 
447 static bool
448 xfs_attr_match(
449 	struct xfs_da_args	*args,
450 	uint8_t			namelen,
451 	unsigned char		*name,
452 	int			flags)
453 {
454 	if (args->namelen != namelen)
455 		return false;
456 	if (memcmp(args->name, name, namelen) != 0)
457 		return false;
458 	/*
459 	 * If we are looking for incomplete entries, show only those, else only
460 	 * show complete entries.
461 	 */
462 	if (args->attr_filter !=
463 	    (flags & (XFS_ATTR_NSP_ONDISK_MASK | XFS_ATTR_INCOMPLETE)))
464 		return false;
465 	return true;
466 }
467 
468 static int
469 xfs_attr_copy_value(
470 	struct xfs_da_args	*args,
471 	unsigned char		*value,
472 	int			valuelen)
473 {
474 	/*
475 	 * No copy if all we have to do is get the length
476 	 */
477 	if (!args->valuelen) {
478 		args->valuelen = valuelen;
479 		return 0;
480 	}
481 
482 	/*
483 	 * No copy if the length of the existing buffer is too small
484 	 */
485 	if (args->valuelen < valuelen) {
486 		args->valuelen = valuelen;
487 		return -ERANGE;
488 	}
489 
490 	if (!args->value) {
491 		args->value = kmem_alloc_large(valuelen, KM_NOLOCKDEP);
492 		if (!args->value)
493 			return -ENOMEM;
494 	}
495 	args->valuelen = valuelen;
496 
497 	/* remote block xattr requires IO for copy-in */
498 	if (args->rmtblkno)
499 		return xfs_attr_rmtval_get(args);
500 
501 	/*
502 	 * This is to prevent a GCC warning because the remote xattr case
503 	 * doesn't have a value to pass in. In that case, we never reach here,
504 	 * but GCC can't work that out and so throws a "passing NULL to
505 	 * memcpy" warning.
506 	 */
507 	if (!value)
508 		return -EINVAL;
509 	memcpy(args->value, value, valuelen);
510 	return 0;
511 }
512 
513 /*========================================================================
514  * External routines when attribute fork size < XFS_LITINO(mp).
515  *========================================================================*/
516 
517 /*
518  * Query whether the total requested number of attr fork bytes of extended
519  * attribute space will be able to fit inline.
520  *
521  * Returns zero if not, else the di_forkoff fork offset to be used in the
522  * literal area for attribute data once the new bytes have been added.
523  *
524  * di_forkoff must be 8 byte aligned, hence is stored as a >>3 value;
525  * special case for dev/uuid inodes, they have fixed size data forks.
526  */
527 int
528 xfs_attr_shortform_bytesfit(
529 	struct xfs_inode	*dp,
530 	int			bytes)
531 {
532 	struct xfs_mount	*mp = dp->i_mount;
533 	int64_t			dsize;
534 	int			minforkoff;
535 	int			maxforkoff;
536 	int			offset;
537 
538 	/*
539 	 * Check if the new size could fit at all first:
540 	 */
541 	if (bytes > XFS_LITINO(mp))
542 		return 0;
543 
544 	/* rounded down */
545 	offset = (XFS_LITINO(mp) - bytes) >> 3;
546 
547 	if (dp->i_df.if_format == XFS_DINODE_FMT_DEV) {
548 		minforkoff = roundup(sizeof(xfs_dev_t), 8) >> 3;
549 		return (offset >= minforkoff) ? minforkoff : 0;
550 	}
551 
552 	/*
553 	 * If the requested numbers of bytes is smaller or equal to the
554 	 * current attribute fork size we can always proceed.
555 	 *
556 	 * Note that if_bytes in the data fork might actually be larger than
557 	 * the current data fork size is due to delalloc extents. In that
558 	 * case either the extent count will go down when they are converted
559 	 * to real extents, or the delalloc conversion will take care of the
560 	 * literal area rebalancing.
561 	 */
562 	if (bytes <= XFS_IFORK_ASIZE(dp))
563 		return dp->i_d.di_forkoff;
564 
565 	/*
566 	 * For attr2 we can try to move the forkoff if there is space in the
567 	 * literal area, but for the old format we are done if there is no
568 	 * space in the fixed attribute fork.
569 	 */
570 	if (!(mp->m_flags & XFS_MOUNT_ATTR2))
571 		return 0;
572 
573 	dsize = dp->i_df.if_bytes;
574 
575 	switch (dp->i_df.if_format) {
576 	case XFS_DINODE_FMT_EXTENTS:
577 		/*
578 		 * If there is no attr fork and the data fork is extents,
579 		 * determine if creating the default attr fork will result
580 		 * in the extents form migrating to btree. If so, the
581 		 * minimum offset only needs to be the space required for
582 		 * the btree root.
583 		 */
584 		if (!dp->i_d.di_forkoff && dp->i_df.if_bytes >
585 		    xfs_default_attroffset(dp))
586 			dsize = XFS_BMDR_SPACE_CALC(MINDBTPTRS);
587 		break;
588 	case XFS_DINODE_FMT_BTREE:
589 		/*
590 		 * If we have a data btree then keep forkoff if we have one,
591 		 * otherwise we are adding a new attr, so then we set
592 		 * minforkoff to where the btree root can finish so we have
593 		 * plenty of room for attrs
594 		 */
595 		if (dp->i_d.di_forkoff) {
596 			if (offset < dp->i_d.di_forkoff)
597 				return 0;
598 			return dp->i_d.di_forkoff;
599 		}
600 		dsize = XFS_BMAP_BROOT_SPACE(mp, dp->i_df.if_broot);
601 		break;
602 	}
603 
604 	/*
605 	 * A data fork btree root must have space for at least
606 	 * MINDBTPTRS key/ptr pairs if the data fork is small or empty.
607 	 */
608 	minforkoff = max_t(int64_t, dsize, XFS_BMDR_SPACE_CALC(MINDBTPTRS));
609 	minforkoff = roundup(minforkoff, 8) >> 3;
610 
611 	/* attr fork btree root can have at least this many key/ptr pairs */
612 	maxforkoff = XFS_LITINO(mp) - XFS_BMDR_SPACE_CALC(MINABTPTRS);
613 	maxforkoff = maxforkoff >> 3;	/* rounded down */
614 
615 	if (offset >= maxforkoff)
616 		return maxforkoff;
617 	if (offset >= minforkoff)
618 		return offset;
619 	return 0;
620 }
621 
622 /*
623  * Switch on the ATTR2 superblock bit (implies also FEATURES2)
624  */
625 STATIC void
626 xfs_sbversion_add_attr2(xfs_mount_t *mp, xfs_trans_t *tp)
627 {
628 	if ((mp->m_flags & XFS_MOUNT_ATTR2) &&
629 	    !(xfs_sb_version_hasattr2(&mp->m_sb))) {
630 		spin_lock(&mp->m_sb_lock);
631 		if (!xfs_sb_version_hasattr2(&mp->m_sb)) {
632 			xfs_sb_version_addattr2(&mp->m_sb);
633 			spin_unlock(&mp->m_sb_lock);
634 			xfs_log_sb(tp);
635 		} else
636 			spin_unlock(&mp->m_sb_lock);
637 	}
638 }
639 
640 /*
641  * Create the initial contents of a shortform attribute list.
642  */
643 void
644 xfs_attr_shortform_create(
645 	struct xfs_da_args	*args)
646 {
647 	struct xfs_inode	*dp = args->dp;
648 	struct xfs_ifork	*ifp = dp->i_afp;
649 	struct xfs_attr_sf_hdr	*hdr;
650 
651 	trace_xfs_attr_sf_create(args);
652 
653 	ASSERT(ifp->if_bytes == 0);
654 	if (ifp->if_format == XFS_DINODE_FMT_EXTENTS) {
655 		ifp->if_flags &= ~XFS_IFEXTENTS;	/* just in case */
656 		ifp->if_format = XFS_DINODE_FMT_LOCAL;
657 		ifp->if_flags |= XFS_IFINLINE;
658 	} else {
659 		ASSERT(ifp->if_flags & XFS_IFINLINE);
660 	}
661 	xfs_idata_realloc(dp, sizeof(*hdr), XFS_ATTR_FORK);
662 	hdr = (struct xfs_attr_sf_hdr *)ifp->if_u1.if_data;
663 	memset(hdr, 0, sizeof(*hdr));
664 	hdr->totsize = cpu_to_be16(sizeof(*hdr));
665 	xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE | XFS_ILOG_ADATA);
666 }
667 
668 /*
669  * Return -EEXIST if attr is found, or -ENOATTR if not
670  * args:  args containing attribute name and namelen
671  * sfep:  If not null, pointer will be set to the last attr entry found on
672 	  -EEXIST.  On -ENOATTR pointer is left at the last entry in the list
673  * basep: If not null, pointer is set to the byte offset of the entry in the
674  *	  list on -EEXIST.  On -ENOATTR, pointer is left at the byte offset of
675  *	  the last entry in the list
676  */
677 int
678 xfs_attr_sf_findname(
679 	struct xfs_da_args	 *args,
680 	struct xfs_attr_sf_entry **sfep,
681 	unsigned int		 *basep)
682 {
683 	struct xfs_attr_shortform *sf;
684 	struct xfs_attr_sf_entry *sfe;
685 	unsigned int		base = sizeof(struct xfs_attr_sf_hdr);
686 	int			size = 0;
687 	int			end;
688 	int			i;
689 
690 	sf = (struct xfs_attr_shortform *)args->dp->i_afp->if_u1.if_data;
691 	sfe = &sf->list[0];
692 	end = sf->hdr.count;
693 	for (i = 0; i < end; sfe = xfs_attr_sf_nextentry(sfe),
694 			     base += size, i++) {
695 		size = xfs_attr_sf_entsize(sfe);
696 		if (!xfs_attr_match(args, sfe->namelen, sfe->nameval,
697 				    sfe->flags))
698 			continue;
699 		break;
700 	}
701 
702 	if (sfep != NULL)
703 		*sfep = sfe;
704 
705 	if (basep != NULL)
706 		*basep = base;
707 
708 	if (i == end)
709 		return -ENOATTR;
710 	return -EEXIST;
711 }
712 
713 /*
714  * Add a name/value pair to the shortform attribute list.
715  * Overflow from the inode has already been checked for.
716  */
717 void
718 xfs_attr_shortform_add(
719 	struct xfs_da_args		*args,
720 	int				forkoff)
721 {
722 	struct xfs_attr_shortform	*sf;
723 	struct xfs_attr_sf_entry	*sfe;
724 	int				offset, size;
725 	struct xfs_mount		*mp;
726 	struct xfs_inode		*dp;
727 	struct xfs_ifork		*ifp;
728 
729 	trace_xfs_attr_sf_add(args);
730 
731 	dp = args->dp;
732 	mp = dp->i_mount;
733 	dp->i_d.di_forkoff = forkoff;
734 
735 	ifp = dp->i_afp;
736 	ASSERT(ifp->if_flags & XFS_IFINLINE);
737 	sf = (struct xfs_attr_shortform *)ifp->if_u1.if_data;
738 	if (xfs_attr_sf_findname(args, &sfe, NULL) == -EEXIST)
739 		ASSERT(0);
740 
741 	offset = (char *)sfe - (char *)sf;
742 	size = xfs_attr_sf_entsize_byname(args->namelen, args->valuelen);
743 	xfs_idata_realloc(dp, size, XFS_ATTR_FORK);
744 	sf = (struct xfs_attr_shortform *)ifp->if_u1.if_data;
745 	sfe = (struct xfs_attr_sf_entry *)((char *)sf + offset);
746 
747 	sfe->namelen = args->namelen;
748 	sfe->valuelen = args->valuelen;
749 	sfe->flags = args->attr_filter;
750 	memcpy(sfe->nameval, args->name, args->namelen);
751 	memcpy(&sfe->nameval[args->namelen], args->value, args->valuelen);
752 	sf->hdr.count++;
753 	be16_add_cpu(&sf->hdr.totsize, size);
754 	xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE | XFS_ILOG_ADATA);
755 
756 	xfs_sbversion_add_attr2(mp, args->trans);
757 }
758 
759 /*
760  * After the last attribute is removed revert to original inode format,
761  * making all literal area available to the data fork once more.
762  */
763 void
764 xfs_attr_fork_remove(
765 	struct xfs_inode	*ip,
766 	struct xfs_trans	*tp)
767 {
768 	ASSERT(ip->i_afp->if_nextents == 0);
769 
770 	xfs_idestroy_fork(ip->i_afp);
771 	kmem_cache_free(xfs_ifork_zone, ip->i_afp);
772 	ip->i_afp = NULL;
773 	ip->i_d.di_forkoff = 0;
774 	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
775 }
776 
777 /*
778  * Remove an attribute from the shortform attribute list structure.
779  */
780 int
781 xfs_attr_shortform_remove(
782 	struct xfs_da_args		*args)
783 {
784 	struct xfs_attr_shortform	*sf;
785 	struct xfs_attr_sf_entry	*sfe;
786 	int				size = 0, end, totsize;
787 	unsigned int			base;
788 	struct xfs_mount		*mp;
789 	struct xfs_inode		*dp;
790 	int				error;
791 
792 	trace_xfs_attr_sf_remove(args);
793 
794 	dp = args->dp;
795 	mp = dp->i_mount;
796 	sf = (struct xfs_attr_shortform *)dp->i_afp->if_u1.if_data;
797 
798 	error = xfs_attr_sf_findname(args, &sfe, &base);
799 	if (error != -EEXIST)
800 		return error;
801 	size = xfs_attr_sf_entsize(sfe);
802 
803 	/*
804 	 * Fix up the attribute fork data, covering the hole
805 	 */
806 	end = base + size;
807 	totsize = be16_to_cpu(sf->hdr.totsize);
808 	if (end != totsize)
809 		memmove(&((char *)sf)[base], &((char *)sf)[end], totsize - end);
810 	sf->hdr.count--;
811 	be16_add_cpu(&sf->hdr.totsize, -size);
812 
813 	/*
814 	 * Fix up the start offset of the attribute fork
815 	 */
816 	totsize -= size;
817 	if (totsize == sizeof(xfs_attr_sf_hdr_t) &&
818 	    (mp->m_flags & XFS_MOUNT_ATTR2) &&
819 	    (dp->i_df.if_format != XFS_DINODE_FMT_BTREE) &&
820 	    !(args->op_flags & XFS_DA_OP_ADDNAME)) {
821 		xfs_attr_fork_remove(dp, args->trans);
822 	} else {
823 		xfs_idata_realloc(dp, -size, XFS_ATTR_FORK);
824 		dp->i_d.di_forkoff = xfs_attr_shortform_bytesfit(dp, totsize);
825 		ASSERT(dp->i_d.di_forkoff);
826 		ASSERT(totsize > sizeof(xfs_attr_sf_hdr_t) ||
827 				(args->op_flags & XFS_DA_OP_ADDNAME) ||
828 				!(mp->m_flags & XFS_MOUNT_ATTR2) ||
829 				dp->i_df.if_format == XFS_DINODE_FMT_BTREE);
830 		xfs_trans_log_inode(args->trans, dp,
831 					XFS_ILOG_CORE | XFS_ILOG_ADATA);
832 	}
833 
834 	xfs_sbversion_add_attr2(mp, args->trans);
835 
836 	return 0;
837 }
838 
839 /*
840  * Look up a name in a shortform attribute list structure.
841  */
842 /*ARGSUSED*/
843 int
844 xfs_attr_shortform_lookup(xfs_da_args_t *args)
845 {
846 	struct xfs_attr_shortform *sf;
847 	struct xfs_attr_sf_entry *sfe;
848 	int i;
849 	struct xfs_ifork *ifp;
850 
851 	trace_xfs_attr_sf_lookup(args);
852 
853 	ifp = args->dp->i_afp;
854 	ASSERT(ifp->if_flags & XFS_IFINLINE);
855 	sf = (struct xfs_attr_shortform *)ifp->if_u1.if_data;
856 	sfe = &sf->list[0];
857 	for (i = 0; i < sf->hdr.count;
858 				sfe = xfs_attr_sf_nextentry(sfe), i++) {
859 		if (xfs_attr_match(args, sfe->namelen, sfe->nameval,
860 				sfe->flags))
861 			return -EEXIST;
862 	}
863 	return -ENOATTR;
864 }
865 
866 /*
867  * Retrieve the attribute value and length.
868  *
869  * If args->valuelen is zero, only the length needs to be returned.  Unlike a
870  * lookup, we only return an error if the attribute does not exist or we can't
871  * retrieve the value.
872  */
873 int
874 xfs_attr_shortform_getvalue(
875 	struct xfs_da_args	*args)
876 {
877 	struct xfs_attr_shortform *sf;
878 	struct xfs_attr_sf_entry *sfe;
879 	int			i;
880 
881 	ASSERT(args->dp->i_afp->if_flags == XFS_IFINLINE);
882 	sf = (struct xfs_attr_shortform *)args->dp->i_afp->if_u1.if_data;
883 	sfe = &sf->list[0];
884 	for (i = 0; i < sf->hdr.count;
885 				sfe = xfs_attr_sf_nextentry(sfe), i++) {
886 		if (xfs_attr_match(args, sfe->namelen, sfe->nameval,
887 				sfe->flags))
888 			return xfs_attr_copy_value(args,
889 				&sfe->nameval[args->namelen], sfe->valuelen);
890 	}
891 	return -ENOATTR;
892 }
893 
894 /*
895  * Convert from using the shortform to the leaf.  On success, return the
896  * buffer so that we can keep it locked until we're totally done with it.
897  */
898 int
899 xfs_attr_shortform_to_leaf(
900 	struct xfs_da_args		*args,
901 	struct xfs_buf			**leaf_bp)
902 {
903 	struct xfs_inode		*dp;
904 	struct xfs_attr_shortform	*sf;
905 	struct xfs_attr_sf_entry	*sfe;
906 	struct xfs_da_args		nargs;
907 	char				*tmpbuffer;
908 	int				error, i, size;
909 	xfs_dablk_t			blkno;
910 	struct xfs_buf			*bp;
911 	struct xfs_ifork		*ifp;
912 
913 	trace_xfs_attr_sf_to_leaf(args);
914 
915 	dp = args->dp;
916 	ifp = dp->i_afp;
917 	sf = (struct xfs_attr_shortform *)ifp->if_u1.if_data;
918 	size = be16_to_cpu(sf->hdr.totsize);
919 	tmpbuffer = kmem_alloc(size, 0);
920 	ASSERT(tmpbuffer != NULL);
921 	memcpy(tmpbuffer, ifp->if_u1.if_data, size);
922 	sf = (struct xfs_attr_shortform *)tmpbuffer;
923 
924 	xfs_idata_realloc(dp, -size, XFS_ATTR_FORK);
925 	xfs_bmap_local_to_extents_empty(args->trans, dp, XFS_ATTR_FORK);
926 
927 	bp = NULL;
928 	error = xfs_da_grow_inode(args, &blkno);
929 	if (error)
930 		goto out;
931 
932 	ASSERT(blkno == 0);
933 	error = xfs_attr3_leaf_create(args, blkno, &bp);
934 	if (error)
935 		goto out;
936 
937 	memset((char *)&nargs, 0, sizeof(nargs));
938 	nargs.dp = dp;
939 	nargs.geo = args->geo;
940 	nargs.total = args->total;
941 	nargs.whichfork = XFS_ATTR_FORK;
942 	nargs.trans = args->trans;
943 	nargs.op_flags = XFS_DA_OP_OKNOENT;
944 
945 	sfe = &sf->list[0];
946 	for (i = 0; i < sf->hdr.count; i++) {
947 		nargs.name = sfe->nameval;
948 		nargs.namelen = sfe->namelen;
949 		nargs.value = &sfe->nameval[nargs.namelen];
950 		nargs.valuelen = sfe->valuelen;
951 		nargs.hashval = xfs_da_hashname(sfe->nameval,
952 						sfe->namelen);
953 		nargs.attr_filter = sfe->flags & XFS_ATTR_NSP_ONDISK_MASK;
954 		error = xfs_attr3_leaf_lookup_int(bp, &nargs); /* set a->index */
955 		ASSERT(error == -ENOATTR);
956 		error = xfs_attr3_leaf_add(bp, &nargs);
957 		ASSERT(error != -ENOSPC);
958 		if (error)
959 			goto out;
960 		sfe = xfs_attr_sf_nextentry(sfe);
961 	}
962 	error = 0;
963 	*leaf_bp = bp;
964 out:
965 	kmem_free(tmpbuffer);
966 	return error;
967 }
968 
969 /*
970  * Check a leaf attribute block to see if all the entries would fit into
971  * a shortform attribute list.
972  */
973 int
974 xfs_attr_shortform_allfit(
975 	struct xfs_buf		*bp,
976 	struct xfs_inode	*dp)
977 {
978 	struct xfs_attr_leafblock *leaf;
979 	struct xfs_attr_leaf_entry *entry;
980 	xfs_attr_leaf_name_local_t *name_loc;
981 	struct xfs_attr3_icleaf_hdr leafhdr;
982 	int			bytes;
983 	int			i;
984 	struct xfs_mount	*mp = bp->b_mount;
985 
986 	leaf = bp->b_addr;
987 	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &leafhdr, leaf);
988 	entry = xfs_attr3_leaf_entryp(leaf);
989 
990 	bytes = sizeof(struct xfs_attr_sf_hdr);
991 	for (i = 0; i < leafhdr.count; entry++, i++) {
992 		if (entry->flags & XFS_ATTR_INCOMPLETE)
993 			continue;		/* don't copy partial entries */
994 		if (!(entry->flags & XFS_ATTR_LOCAL))
995 			return 0;
996 		name_loc = xfs_attr3_leaf_name_local(leaf, i);
997 		if (name_loc->namelen >= XFS_ATTR_SF_ENTSIZE_MAX)
998 			return 0;
999 		if (be16_to_cpu(name_loc->valuelen) >= XFS_ATTR_SF_ENTSIZE_MAX)
1000 			return 0;
1001 		bytes += xfs_attr_sf_entsize_byname(name_loc->namelen,
1002 					be16_to_cpu(name_loc->valuelen));
1003 	}
1004 	if ((dp->i_mount->m_flags & XFS_MOUNT_ATTR2) &&
1005 	    (dp->i_df.if_format != XFS_DINODE_FMT_BTREE) &&
1006 	    (bytes == sizeof(struct xfs_attr_sf_hdr)))
1007 		return -1;
1008 	return xfs_attr_shortform_bytesfit(dp, bytes);
1009 }
1010 
1011 /* Verify the consistency of an inline attribute fork. */
1012 xfs_failaddr_t
1013 xfs_attr_shortform_verify(
1014 	struct xfs_inode		*ip)
1015 {
1016 	struct xfs_attr_shortform	*sfp;
1017 	struct xfs_attr_sf_entry	*sfep;
1018 	struct xfs_attr_sf_entry	*next_sfep;
1019 	char				*endp;
1020 	struct xfs_ifork		*ifp;
1021 	int				i;
1022 	int64_t				size;
1023 
1024 	ASSERT(ip->i_afp->if_format == XFS_DINODE_FMT_LOCAL);
1025 	ifp = XFS_IFORK_PTR(ip, XFS_ATTR_FORK);
1026 	sfp = (struct xfs_attr_shortform *)ifp->if_u1.if_data;
1027 	size = ifp->if_bytes;
1028 
1029 	/*
1030 	 * Give up if the attribute is way too short.
1031 	 */
1032 	if (size < sizeof(struct xfs_attr_sf_hdr))
1033 		return __this_address;
1034 
1035 	endp = (char *)sfp + size;
1036 
1037 	/* Check all reported entries */
1038 	sfep = &sfp->list[0];
1039 	for (i = 0; i < sfp->hdr.count; i++) {
1040 		/*
1041 		 * struct xfs_attr_sf_entry has a variable length.
1042 		 * Check the fixed-offset parts of the structure are
1043 		 * within the data buffer.
1044 		 * xfs_attr_sf_entry is defined with a 1-byte variable
1045 		 * array at the end, so we must subtract that off.
1046 		 */
1047 		if (((char *)sfep + sizeof(*sfep)) >= endp)
1048 			return __this_address;
1049 
1050 		/* Don't allow names with known bad length. */
1051 		if (sfep->namelen == 0)
1052 			return __this_address;
1053 
1054 		/*
1055 		 * Check that the variable-length part of the structure is
1056 		 * within the data buffer.  The next entry starts after the
1057 		 * name component, so nextentry is an acceptable test.
1058 		 */
1059 		next_sfep = xfs_attr_sf_nextentry(sfep);
1060 		if ((char *)next_sfep > endp)
1061 			return __this_address;
1062 
1063 		/*
1064 		 * Check for unknown flags.  Short form doesn't support
1065 		 * the incomplete or local bits, so we can use the namespace
1066 		 * mask here.
1067 		 */
1068 		if (sfep->flags & ~XFS_ATTR_NSP_ONDISK_MASK)
1069 			return __this_address;
1070 
1071 		/*
1072 		 * Check for invalid namespace combinations.  We only allow
1073 		 * one namespace flag per xattr, so we can just count the
1074 		 * bits (i.e. hweight) here.
1075 		 */
1076 		if (hweight8(sfep->flags & XFS_ATTR_NSP_ONDISK_MASK) > 1)
1077 			return __this_address;
1078 
1079 		sfep = next_sfep;
1080 	}
1081 	if ((void *)sfep != (void *)endp)
1082 		return __this_address;
1083 
1084 	return NULL;
1085 }
1086 
1087 /*
1088  * Convert a leaf attribute list to shortform attribute list
1089  */
1090 int
1091 xfs_attr3_leaf_to_shortform(
1092 	struct xfs_buf		*bp,
1093 	struct xfs_da_args	*args,
1094 	int			forkoff)
1095 {
1096 	struct xfs_attr_leafblock *leaf;
1097 	struct xfs_attr3_icleaf_hdr ichdr;
1098 	struct xfs_attr_leaf_entry *entry;
1099 	struct xfs_attr_leaf_name_local *name_loc;
1100 	struct xfs_da_args	nargs;
1101 	struct xfs_inode	*dp = args->dp;
1102 	char			*tmpbuffer;
1103 	int			error;
1104 	int			i;
1105 
1106 	trace_xfs_attr_leaf_to_sf(args);
1107 
1108 	tmpbuffer = kmem_alloc(args->geo->blksize, 0);
1109 	if (!tmpbuffer)
1110 		return -ENOMEM;
1111 
1112 	memcpy(tmpbuffer, bp->b_addr, args->geo->blksize);
1113 
1114 	leaf = (xfs_attr_leafblock_t *)tmpbuffer;
1115 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
1116 	entry = xfs_attr3_leaf_entryp(leaf);
1117 
1118 	/* XXX (dgc): buffer is about to be marked stale - why zero it? */
1119 	memset(bp->b_addr, 0, args->geo->blksize);
1120 
1121 	/*
1122 	 * Clean out the prior contents of the attribute list.
1123 	 */
1124 	error = xfs_da_shrink_inode(args, 0, bp);
1125 	if (error)
1126 		goto out;
1127 
1128 	if (forkoff == -1) {
1129 		ASSERT(dp->i_mount->m_flags & XFS_MOUNT_ATTR2);
1130 		ASSERT(dp->i_df.if_format != XFS_DINODE_FMT_BTREE);
1131 		xfs_attr_fork_remove(dp, args->trans);
1132 		goto out;
1133 	}
1134 
1135 	xfs_attr_shortform_create(args);
1136 
1137 	/*
1138 	 * Copy the attributes
1139 	 */
1140 	memset((char *)&nargs, 0, sizeof(nargs));
1141 	nargs.geo = args->geo;
1142 	nargs.dp = dp;
1143 	nargs.total = args->total;
1144 	nargs.whichfork = XFS_ATTR_FORK;
1145 	nargs.trans = args->trans;
1146 	nargs.op_flags = XFS_DA_OP_OKNOENT;
1147 
1148 	for (i = 0; i < ichdr.count; entry++, i++) {
1149 		if (entry->flags & XFS_ATTR_INCOMPLETE)
1150 			continue;	/* don't copy partial entries */
1151 		if (!entry->nameidx)
1152 			continue;
1153 		ASSERT(entry->flags & XFS_ATTR_LOCAL);
1154 		name_loc = xfs_attr3_leaf_name_local(leaf, i);
1155 		nargs.name = name_loc->nameval;
1156 		nargs.namelen = name_loc->namelen;
1157 		nargs.value = &name_loc->nameval[nargs.namelen];
1158 		nargs.valuelen = be16_to_cpu(name_loc->valuelen);
1159 		nargs.hashval = be32_to_cpu(entry->hashval);
1160 		nargs.attr_filter = entry->flags & XFS_ATTR_NSP_ONDISK_MASK;
1161 		xfs_attr_shortform_add(&nargs, forkoff);
1162 	}
1163 	error = 0;
1164 
1165 out:
1166 	kmem_free(tmpbuffer);
1167 	return error;
1168 }
1169 
1170 /*
1171  * Convert from using a single leaf to a root node and a leaf.
1172  */
1173 int
1174 xfs_attr3_leaf_to_node(
1175 	struct xfs_da_args	*args)
1176 {
1177 	struct xfs_attr_leafblock *leaf;
1178 	struct xfs_attr3_icleaf_hdr icleafhdr;
1179 	struct xfs_attr_leaf_entry *entries;
1180 	struct xfs_da3_icnode_hdr icnodehdr;
1181 	struct xfs_da_intnode	*node;
1182 	struct xfs_inode	*dp = args->dp;
1183 	struct xfs_mount	*mp = dp->i_mount;
1184 	struct xfs_buf		*bp1 = NULL;
1185 	struct xfs_buf		*bp2 = NULL;
1186 	xfs_dablk_t		blkno;
1187 	int			error;
1188 
1189 	trace_xfs_attr_leaf_to_node(args);
1190 
1191 	error = xfs_da_grow_inode(args, &blkno);
1192 	if (error)
1193 		goto out;
1194 	error = xfs_attr3_leaf_read(args->trans, dp, 0, &bp1);
1195 	if (error)
1196 		goto out;
1197 
1198 	error = xfs_da_get_buf(args->trans, dp, blkno, &bp2, XFS_ATTR_FORK);
1199 	if (error)
1200 		goto out;
1201 
1202 	/* copy leaf to new buffer, update identifiers */
1203 	xfs_trans_buf_set_type(args->trans, bp2, XFS_BLFT_ATTR_LEAF_BUF);
1204 	bp2->b_ops = bp1->b_ops;
1205 	memcpy(bp2->b_addr, bp1->b_addr, args->geo->blksize);
1206 	if (xfs_sb_version_hascrc(&mp->m_sb)) {
1207 		struct xfs_da3_blkinfo *hdr3 = bp2->b_addr;
1208 		hdr3->blkno = cpu_to_be64(bp2->b_bn);
1209 	}
1210 	xfs_trans_log_buf(args->trans, bp2, 0, args->geo->blksize - 1);
1211 
1212 	/*
1213 	 * Set up the new root node.
1214 	 */
1215 	error = xfs_da3_node_create(args, 0, 1, &bp1, XFS_ATTR_FORK);
1216 	if (error)
1217 		goto out;
1218 	node = bp1->b_addr;
1219 	xfs_da3_node_hdr_from_disk(mp, &icnodehdr, node);
1220 
1221 	leaf = bp2->b_addr;
1222 	xfs_attr3_leaf_hdr_from_disk(args->geo, &icleafhdr, leaf);
1223 	entries = xfs_attr3_leaf_entryp(leaf);
1224 
1225 	/* both on-disk, don't endian-flip twice */
1226 	icnodehdr.btree[0].hashval = entries[icleafhdr.count - 1].hashval;
1227 	icnodehdr.btree[0].before = cpu_to_be32(blkno);
1228 	icnodehdr.count = 1;
1229 	xfs_da3_node_hdr_to_disk(dp->i_mount, node, &icnodehdr);
1230 	xfs_trans_log_buf(args->trans, bp1, 0, args->geo->blksize - 1);
1231 	error = 0;
1232 out:
1233 	return error;
1234 }
1235 
1236 /*========================================================================
1237  * Routines used for growing the Btree.
1238  *========================================================================*/
1239 
1240 /*
1241  * Create the initial contents of a leaf attribute list
1242  * or a leaf in a node attribute list.
1243  */
1244 STATIC int
1245 xfs_attr3_leaf_create(
1246 	struct xfs_da_args	*args,
1247 	xfs_dablk_t		blkno,
1248 	struct xfs_buf		**bpp)
1249 {
1250 	struct xfs_attr_leafblock *leaf;
1251 	struct xfs_attr3_icleaf_hdr ichdr;
1252 	struct xfs_inode	*dp = args->dp;
1253 	struct xfs_mount	*mp = dp->i_mount;
1254 	struct xfs_buf		*bp;
1255 	int			error;
1256 
1257 	trace_xfs_attr_leaf_create(args);
1258 
1259 	error = xfs_da_get_buf(args->trans, args->dp, blkno, &bp,
1260 					    XFS_ATTR_FORK);
1261 	if (error)
1262 		return error;
1263 	bp->b_ops = &xfs_attr3_leaf_buf_ops;
1264 	xfs_trans_buf_set_type(args->trans, bp, XFS_BLFT_ATTR_LEAF_BUF);
1265 	leaf = bp->b_addr;
1266 	memset(leaf, 0, args->geo->blksize);
1267 
1268 	memset(&ichdr, 0, sizeof(ichdr));
1269 	ichdr.firstused = args->geo->blksize;
1270 
1271 	if (xfs_sb_version_hascrc(&mp->m_sb)) {
1272 		struct xfs_da3_blkinfo *hdr3 = bp->b_addr;
1273 
1274 		ichdr.magic = XFS_ATTR3_LEAF_MAGIC;
1275 
1276 		hdr3->blkno = cpu_to_be64(bp->b_bn);
1277 		hdr3->owner = cpu_to_be64(dp->i_ino);
1278 		uuid_copy(&hdr3->uuid, &mp->m_sb.sb_meta_uuid);
1279 
1280 		ichdr.freemap[0].base = sizeof(struct xfs_attr3_leaf_hdr);
1281 	} else {
1282 		ichdr.magic = XFS_ATTR_LEAF_MAGIC;
1283 		ichdr.freemap[0].base = sizeof(struct xfs_attr_leaf_hdr);
1284 	}
1285 	ichdr.freemap[0].size = ichdr.firstused - ichdr.freemap[0].base;
1286 
1287 	xfs_attr3_leaf_hdr_to_disk(args->geo, leaf, &ichdr);
1288 	xfs_trans_log_buf(args->trans, bp, 0, args->geo->blksize - 1);
1289 
1290 	*bpp = bp;
1291 	return 0;
1292 }
1293 
1294 /*
1295  * Split the leaf node, rebalance, then add the new entry.
1296  */
1297 int
1298 xfs_attr3_leaf_split(
1299 	struct xfs_da_state	*state,
1300 	struct xfs_da_state_blk	*oldblk,
1301 	struct xfs_da_state_blk	*newblk)
1302 {
1303 	xfs_dablk_t blkno;
1304 	int error;
1305 
1306 	trace_xfs_attr_leaf_split(state->args);
1307 
1308 	/*
1309 	 * Allocate space for a new leaf node.
1310 	 */
1311 	ASSERT(oldblk->magic == XFS_ATTR_LEAF_MAGIC);
1312 	error = xfs_da_grow_inode(state->args, &blkno);
1313 	if (error)
1314 		return error;
1315 	error = xfs_attr3_leaf_create(state->args, blkno, &newblk->bp);
1316 	if (error)
1317 		return error;
1318 	newblk->blkno = blkno;
1319 	newblk->magic = XFS_ATTR_LEAF_MAGIC;
1320 
1321 	/*
1322 	 * Rebalance the entries across the two leaves.
1323 	 * NOTE: rebalance() currently depends on the 2nd block being empty.
1324 	 */
1325 	xfs_attr3_leaf_rebalance(state, oldblk, newblk);
1326 	error = xfs_da3_blk_link(state, oldblk, newblk);
1327 	if (error)
1328 		return error;
1329 
1330 	/*
1331 	 * Save info on "old" attribute for "atomic rename" ops, leaf_add()
1332 	 * modifies the index/blkno/rmtblk/rmtblkcnt fields to show the
1333 	 * "new" attrs info.  Will need the "old" info to remove it later.
1334 	 *
1335 	 * Insert the "new" entry in the correct block.
1336 	 */
1337 	if (state->inleaf) {
1338 		trace_xfs_attr_leaf_add_old(state->args);
1339 		error = xfs_attr3_leaf_add(oldblk->bp, state->args);
1340 	} else {
1341 		trace_xfs_attr_leaf_add_new(state->args);
1342 		error = xfs_attr3_leaf_add(newblk->bp, state->args);
1343 	}
1344 
1345 	/*
1346 	 * Update last hashval in each block since we added the name.
1347 	 */
1348 	oldblk->hashval = xfs_attr_leaf_lasthash(oldblk->bp, NULL);
1349 	newblk->hashval = xfs_attr_leaf_lasthash(newblk->bp, NULL);
1350 	return error;
1351 }
1352 
1353 /*
1354  * Add a name to the leaf attribute list structure.
1355  */
1356 int
1357 xfs_attr3_leaf_add(
1358 	struct xfs_buf		*bp,
1359 	struct xfs_da_args	*args)
1360 {
1361 	struct xfs_attr_leafblock *leaf;
1362 	struct xfs_attr3_icleaf_hdr ichdr;
1363 	int			tablesize;
1364 	int			entsize;
1365 	int			sum;
1366 	int			tmp;
1367 	int			i;
1368 
1369 	trace_xfs_attr_leaf_add(args);
1370 
1371 	leaf = bp->b_addr;
1372 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
1373 	ASSERT(args->index >= 0 && args->index <= ichdr.count);
1374 	entsize = xfs_attr_leaf_newentsize(args, NULL);
1375 
1376 	/*
1377 	 * Search through freemap for first-fit on new name length.
1378 	 * (may need to figure in size of entry struct too)
1379 	 */
1380 	tablesize = (ichdr.count + 1) * sizeof(xfs_attr_leaf_entry_t)
1381 					+ xfs_attr3_leaf_hdr_size(leaf);
1382 	for (sum = 0, i = XFS_ATTR_LEAF_MAPSIZE - 1; i >= 0; i--) {
1383 		if (tablesize > ichdr.firstused) {
1384 			sum += ichdr.freemap[i].size;
1385 			continue;
1386 		}
1387 		if (!ichdr.freemap[i].size)
1388 			continue;	/* no space in this map */
1389 		tmp = entsize;
1390 		if (ichdr.freemap[i].base < ichdr.firstused)
1391 			tmp += sizeof(xfs_attr_leaf_entry_t);
1392 		if (ichdr.freemap[i].size >= tmp) {
1393 			tmp = xfs_attr3_leaf_add_work(bp, &ichdr, args, i);
1394 			goto out_log_hdr;
1395 		}
1396 		sum += ichdr.freemap[i].size;
1397 	}
1398 
1399 	/*
1400 	 * If there are no holes in the address space of the block,
1401 	 * and we don't have enough freespace, then compaction will do us
1402 	 * no good and we should just give up.
1403 	 */
1404 	if (!ichdr.holes && sum < entsize)
1405 		return -ENOSPC;
1406 
1407 	/*
1408 	 * Compact the entries to coalesce free space.
1409 	 * This may change the hdr->count via dropping INCOMPLETE entries.
1410 	 */
1411 	xfs_attr3_leaf_compact(args, &ichdr, bp);
1412 
1413 	/*
1414 	 * After compaction, the block is guaranteed to have only one
1415 	 * free region, in freemap[0].  If it is not big enough, give up.
1416 	 */
1417 	if (ichdr.freemap[0].size < (entsize + sizeof(xfs_attr_leaf_entry_t))) {
1418 		tmp = -ENOSPC;
1419 		goto out_log_hdr;
1420 	}
1421 
1422 	tmp = xfs_attr3_leaf_add_work(bp, &ichdr, args, 0);
1423 
1424 out_log_hdr:
1425 	xfs_attr3_leaf_hdr_to_disk(args->geo, leaf, &ichdr);
1426 	xfs_trans_log_buf(args->trans, bp,
1427 		XFS_DA_LOGRANGE(leaf, &leaf->hdr,
1428 				xfs_attr3_leaf_hdr_size(leaf)));
1429 	return tmp;
1430 }
1431 
1432 /*
1433  * Add a name to a leaf attribute list structure.
1434  */
1435 STATIC int
1436 xfs_attr3_leaf_add_work(
1437 	struct xfs_buf		*bp,
1438 	struct xfs_attr3_icleaf_hdr *ichdr,
1439 	struct xfs_da_args	*args,
1440 	int			mapindex)
1441 {
1442 	struct xfs_attr_leafblock *leaf;
1443 	struct xfs_attr_leaf_entry *entry;
1444 	struct xfs_attr_leaf_name_local *name_loc;
1445 	struct xfs_attr_leaf_name_remote *name_rmt;
1446 	struct xfs_mount	*mp;
1447 	int			tmp;
1448 	int			i;
1449 
1450 	trace_xfs_attr_leaf_add_work(args);
1451 
1452 	leaf = bp->b_addr;
1453 	ASSERT(mapindex >= 0 && mapindex < XFS_ATTR_LEAF_MAPSIZE);
1454 	ASSERT(args->index >= 0 && args->index <= ichdr->count);
1455 
1456 	/*
1457 	 * Force open some space in the entry array and fill it in.
1458 	 */
1459 	entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
1460 	if (args->index < ichdr->count) {
1461 		tmp  = ichdr->count - args->index;
1462 		tmp *= sizeof(xfs_attr_leaf_entry_t);
1463 		memmove(entry + 1, entry, tmp);
1464 		xfs_trans_log_buf(args->trans, bp,
1465 		    XFS_DA_LOGRANGE(leaf, entry, tmp + sizeof(*entry)));
1466 	}
1467 	ichdr->count++;
1468 
1469 	/*
1470 	 * Allocate space for the new string (at the end of the run).
1471 	 */
1472 	mp = args->trans->t_mountp;
1473 	ASSERT(ichdr->freemap[mapindex].base < args->geo->blksize);
1474 	ASSERT((ichdr->freemap[mapindex].base & 0x3) == 0);
1475 	ASSERT(ichdr->freemap[mapindex].size >=
1476 		xfs_attr_leaf_newentsize(args, NULL));
1477 	ASSERT(ichdr->freemap[mapindex].size < args->geo->blksize);
1478 	ASSERT((ichdr->freemap[mapindex].size & 0x3) == 0);
1479 
1480 	ichdr->freemap[mapindex].size -= xfs_attr_leaf_newentsize(args, &tmp);
1481 
1482 	entry->nameidx = cpu_to_be16(ichdr->freemap[mapindex].base +
1483 				     ichdr->freemap[mapindex].size);
1484 	entry->hashval = cpu_to_be32(args->hashval);
1485 	entry->flags = args->attr_filter;
1486 	if (tmp)
1487 		entry->flags |= XFS_ATTR_LOCAL;
1488 	if (args->op_flags & XFS_DA_OP_RENAME) {
1489 		entry->flags |= XFS_ATTR_INCOMPLETE;
1490 		if ((args->blkno2 == args->blkno) &&
1491 		    (args->index2 <= args->index)) {
1492 			args->index2++;
1493 		}
1494 	}
1495 	xfs_trans_log_buf(args->trans, bp,
1496 			  XFS_DA_LOGRANGE(leaf, entry, sizeof(*entry)));
1497 	ASSERT((args->index == 0) ||
1498 	       (be32_to_cpu(entry->hashval) >= be32_to_cpu((entry-1)->hashval)));
1499 	ASSERT((args->index == ichdr->count - 1) ||
1500 	       (be32_to_cpu(entry->hashval) <= be32_to_cpu((entry+1)->hashval)));
1501 
1502 	/*
1503 	 * For "remote" attribute values, simply note that we need to
1504 	 * allocate space for the "remote" value.  We can't actually
1505 	 * allocate the extents in this transaction, and we can't decide
1506 	 * which blocks they should be as we might allocate more blocks
1507 	 * as part of this transaction (a split operation for example).
1508 	 */
1509 	if (entry->flags & XFS_ATTR_LOCAL) {
1510 		name_loc = xfs_attr3_leaf_name_local(leaf, args->index);
1511 		name_loc->namelen = args->namelen;
1512 		name_loc->valuelen = cpu_to_be16(args->valuelen);
1513 		memcpy((char *)name_loc->nameval, args->name, args->namelen);
1514 		memcpy((char *)&name_loc->nameval[args->namelen], args->value,
1515 				   be16_to_cpu(name_loc->valuelen));
1516 	} else {
1517 		name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
1518 		name_rmt->namelen = args->namelen;
1519 		memcpy((char *)name_rmt->name, args->name, args->namelen);
1520 		entry->flags |= XFS_ATTR_INCOMPLETE;
1521 		/* just in case */
1522 		name_rmt->valuelen = 0;
1523 		name_rmt->valueblk = 0;
1524 		args->rmtblkno = 1;
1525 		args->rmtblkcnt = xfs_attr3_rmt_blocks(mp, args->valuelen);
1526 		args->rmtvaluelen = args->valuelen;
1527 	}
1528 	xfs_trans_log_buf(args->trans, bp,
1529 	     XFS_DA_LOGRANGE(leaf, xfs_attr3_leaf_name(leaf, args->index),
1530 				   xfs_attr_leaf_entsize(leaf, args->index)));
1531 
1532 	/*
1533 	 * Update the control info for this leaf node
1534 	 */
1535 	if (be16_to_cpu(entry->nameidx) < ichdr->firstused)
1536 		ichdr->firstused = be16_to_cpu(entry->nameidx);
1537 
1538 	ASSERT(ichdr->firstused >= ichdr->count * sizeof(xfs_attr_leaf_entry_t)
1539 					+ xfs_attr3_leaf_hdr_size(leaf));
1540 	tmp = (ichdr->count - 1) * sizeof(xfs_attr_leaf_entry_t)
1541 					+ xfs_attr3_leaf_hdr_size(leaf);
1542 
1543 	for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
1544 		if (ichdr->freemap[i].base == tmp) {
1545 			ichdr->freemap[i].base += sizeof(xfs_attr_leaf_entry_t);
1546 			ichdr->freemap[i].size -=
1547 				min_t(uint16_t, ichdr->freemap[i].size,
1548 						sizeof(xfs_attr_leaf_entry_t));
1549 		}
1550 	}
1551 	ichdr->usedbytes += xfs_attr_leaf_entsize(leaf, args->index);
1552 	return 0;
1553 }
1554 
1555 /*
1556  * Garbage collect a leaf attribute list block by copying it to a new buffer.
1557  */
1558 STATIC void
1559 xfs_attr3_leaf_compact(
1560 	struct xfs_da_args	*args,
1561 	struct xfs_attr3_icleaf_hdr *ichdr_dst,
1562 	struct xfs_buf		*bp)
1563 {
1564 	struct xfs_attr_leafblock *leaf_src;
1565 	struct xfs_attr_leafblock *leaf_dst;
1566 	struct xfs_attr3_icleaf_hdr ichdr_src;
1567 	struct xfs_trans	*trans = args->trans;
1568 	char			*tmpbuffer;
1569 
1570 	trace_xfs_attr_leaf_compact(args);
1571 
1572 	tmpbuffer = kmem_alloc(args->geo->blksize, 0);
1573 	memcpy(tmpbuffer, bp->b_addr, args->geo->blksize);
1574 	memset(bp->b_addr, 0, args->geo->blksize);
1575 	leaf_src = (xfs_attr_leafblock_t *)tmpbuffer;
1576 	leaf_dst = bp->b_addr;
1577 
1578 	/*
1579 	 * Copy the on-disk header back into the destination buffer to ensure
1580 	 * all the information in the header that is not part of the incore
1581 	 * header structure is preserved.
1582 	 */
1583 	memcpy(bp->b_addr, tmpbuffer, xfs_attr3_leaf_hdr_size(leaf_src));
1584 
1585 	/* Initialise the incore headers */
1586 	ichdr_src = *ichdr_dst;	/* struct copy */
1587 	ichdr_dst->firstused = args->geo->blksize;
1588 	ichdr_dst->usedbytes = 0;
1589 	ichdr_dst->count = 0;
1590 	ichdr_dst->holes = 0;
1591 	ichdr_dst->freemap[0].base = xfs_attr3_leaf_hdr_size(leaf_src);
1592 	ichdr_dst->freemap[0].size = ichdr_dst->firstused -
1593 						ichdr_dst->freemap[0].base;
1594 
1595 	/* write the header back to initialise the underlying buffer */
1596 	xfs_attr3_leaf_hdr_to_disk(args->geo, leaf_dst, ichdr_dst);
1597 
1598 	/*
1599 	 * Copy all entry's in the same (sorted) order,
1600 	 * but allocate name/value pairs packed and in sequence.
1601 	 */
1602 	xfs_attr3_leaf_moveents(args, leaf_src, &ichdr_src, 0,
1603 				leaf_dst, ichdr_dst, 0, ichdr_src.count);
1604 	/*
1605 	 * this logs the entire buffer, but the caller must write the header
1606 	 * back to the buffer when it is finished modifying it.
1607 	 */
1608 	xfs_trans_log_buf(trans, bp, 0, args->geo->blksize - 1);
1609 
1610 	kmem_free(tmpbuffer);
1611 }
1612 
1613 /*
1614  * Compare two leaf blocks "order".
1615  * Return 0 unless leaf2 should go before leaf1.
1616  */
1617 static int
1618 xfs_attr3_leaf_order(
1619 	struct xfs_buf	*leaf1_bp,
1620 	struct xfs_attr3_icleaf_hdr *leaf1hdr,
1621 	struct xfs_buf	*leaf2_bp,
1622 	struct xfs_attr3_icleaf_hdr *leaf2hdr)
1623 {
1624 	struct xfs_attr_leaf_entry *entries1;
1625 	struct xfs_attr_leaf_entry *entries2;
1626 
1627 	entries1 = xfs_attr3_leaf_entryp(leaf1_bp->b_addr);
1628 	entries2 = xfs_attr3_leaf_entryp(leaf2_bp->b_addr);
1629 	if (leaf1hdr->count > 0 && leaf2hdr->count > 0 &&
1630 	    ((be32_to_cpu(entries2[0].hashval) <
1631 	      be32_to_cpu(entries1[0].hashval)) ||
1632 	     (be32_to_cpu(entries2[leaf2hdr->count - 1].hashval) <
1633 	      be32_to_cpu(entries1[leaf1hdr->count - 1].hashval)))) {
1634 		return 1;
1635 	}
1636 	return 0;
1637 }
1638 
1639 int
1640 xfs_attr_leaf_order(
1641 	struct xfs_buf	*leaf1_bp,
1642 	struct xfs_buf	*leaf2_bp)
1643 {
1644 	struct xfs_attr3_icleaf_hdr ichdr1;
1645 	struct xfs_attr3_icleaf_hdr ichdr2;
1646 	struct xfs_mount *mp = leaf1_bp->b_mount;
1647 
1648 	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr1, leaf1_bp->b_addr);
1649 	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr2, leaf2_bp->b_addr);
1650 	return xfs_attr3_leaf_order(leaf1_bp, &ichdr1, leaf2_bp, &ichdr2);
1651 }
1652 
1653 /*
1654  * Redistribute the attribute list entries between two leaf nodes,
1655  * taking into account the size of the new entry.
1656  *
1657  * NOTE: if new block is empty, then it will get the upper half of the
1658  * old block.  At present, all (one) callers pass in an empty second block.
1659  *
1660  * This code adjusts the args->index/blkno and args->index2/blkno2 fields
1661  * to match what it is doing in splitting the attribute leaf block.  Those
1662  * values are used in "atomic rename" operations on attributes.  Note that
1663  * the "new" and "old" values can end up in different blocks.
1664  */
1665 STATIC void
1666 xfs_attr3_leaf_rebalance(
1667 	struct xfs_da_state	*state,
1668 	struct xfs_da_state_blk	*blk1,
1669 	struct xfs_da_state_blk	*blk2)
1670 {
1671 	struct xfs_da_args	*args;
1672 	struct xfs_attr_leafblock *leaf1;
1673 	struct xfs_attr_leafblock *leaf2;
1674 	struct xfs_attr3_icleaf_hdr ichdr1;
1675 	struct xfs_attr3_icleaf_hdr ichdr2;
1676 	struct xfs_attr_leaf_entry *entries1;
1677 	struct xfs_attr_leaf_entry *entries2;
1678 	int			count;
1679 	int			totallen;
1680 	int			max;
1681 	int			space;
1682 	int			swap;
1683 
1684 	/*
1685 	 * Set up environment.
1686 	 */
1687 	ASSERT(blk1->magic == XFS_ATTR_LEAF_MAGIC);
1688 	ASSERT(blk2->magic == XFS_ATTR_LEAF_MAGIC);
1689 	leaf1 = blk1->bp->b_addr;
1690 	leaf2 = blk2->bp->b_addr;
1691 	xfs_attr3_leaf_hdr_from_disk(state->args->geo, &ichdr1, leaf1);
1692 	xfs_attr3_leaf_hdr_from_disk(state->args->geo, &ichdr2, leaf2);
1693 	ASSERT(ichdr2.count == 0);
1694 	args = state->args;
1695 
1696 	trace_xfs_attr_leaf_rebalance(args);
1697 
1698 	/*
1699 	 * Check ordering of blocks, reverse if it makes things simpler.
1700 	 *
1701 	 * NOTE: Given that all (current) callers pass in an empty
1702 	 * second block, this code should never set "swap".
1703 	 */
1704 	swap = 0;
1705 	if (xfs_attr3_leaf_order(blk1->bp, &ichdr1, blk2->bp, &ichdr2)) {
1706 		swap(blk1, blk2);
1707 
1708 		/* swap structures rather than reconverting them */
1709 		swap(ichdr1, ichdr2);
1710 
1711 		leaf1 = blk1->bp->b_addr;
1712 		leaf2 = blk2->bp->b_addr;
1713 		swap = 1;
1714 	}
1715 
1716 	/*
1717 	 * Examine entries until we reduce the absolute difference in
1718 	 * byte usage between the two blocks to a minimum.  Then get
1719 	 * the direction to copy and the number of elements to move.
1720 	 *
1721 	 * "inleaf" is true if the new entry should be inserted into blk1.
1722 	 * If "swap" is also true, then reverse the sense of "inleaf".
1723 	 */
1724 	state->inleaf = xfs_attr3_leaf_figure_balance(state, blk1, &ichdr1,
1725 						      blk2, &ichdr2,
1726 						      &count, &totallen);
1727 	if (swap)
1728 		state->inleaf = !state->inleaf;
1729 
1730 	/*
1731 	 * Move any entries required from leaf to leaf:
1732 	 */
1733 	if (count < ichdr1.count) {
1734 		/*
1735 		 * Figure the total bytes to be added to the destination leaf.
1736 		 */
1737 		/* number entries being moved */
1738 		count = ichdr1.count - count;
1739 		space  = ichdr1.usedbytes - totallen;
1740 		space += count * sizeof(xfs_attr_leaf_entry_t);
1741 
1742 		/*
1743 		 * leaf2 is the destination, compact it if it looks tight.
1744 		 */
1745 		max  = ichdr2.firstused - xfs_attr3_leaf_hdr_size(leaf1);
1746 		max -= ichdr2.count * sizeof(xfs_attr_leaf_entry_t);
1747 		if (space > max)
1748 			xfs_attr3_leaf_compact(args, &ichdr2, blk2->bp);
1749 
1750 		/*
1751 		 * Move high entries from leaf1 to low end of leaf2.
1752 		 */
1753 		xfs_attr3_leaf_moveents(args, leaf1, &ichdr1,
1754 				ichdr1.count - count, leaf2, &ichdr2, 0, count);
1755 
1756 	} else if (count > ichdr1.count) {
1757 		/*
1758 		 * I assert that since all callers pass in an empty
1759 		 * second buffer, this code should never execute.
1760 		 */
1761 		ASSERT(0);
1762 
1763 		/*
1764 		 * Figure the total bytes to be added to the destination leaf.
1765 		 */
1766 		/* number entries being moved */
1767 		count -= ichdr1.count;
1768 		space  = totallen - ichdr1.usedbytes;
1769 		space += count * sizeof(xfs_attr_leaf_entry_t);
1770 
1771 		/*
1772 		 * leaf1 is the destination, compact it if it looks tight.
1773 		 */
1774 		max  = ichdr1.firstused - xfs_attr3_leaf_hdr_size(leaf1);
1775 		max -= ichdr1.count * sizeof(xfs_attr_leaf_entry_t);
1776 		if (space > max)
1777 			xfs_attr3_leaf_compact(args, &ichdr1, blk1->bp);
1778 
1779 		/*
1780 		 * Move low entries from leaf2 to high end of leaf1.
1781 		 */
1782 		xfs_attr3_leaf_moveents(args, leaf2, &ichdr2, 0, leaf1, &ichdr1,
1783 					ichdr1.count, count);
1784 	}
1785 
1786 	xfs_attr3_leaf_hdr_to_disk(state->args->geo, leaf1, &ichdr1);
1787 	xfs_attr3_leaf_hdr_to_disk(state->args->geo, leaf2, &ichdr2);
1788 	xfs_trans_log_buf(args->trans, blk1->bp, 0, args->geo->blksize - 1);
1789 	xfs_trans_log_buf(args->trans, blk2->bp, 0, args->geo->blksize - 1);
1790 
1791 	/*
1792 	 * Copy out last hashval in each block for B-tree code.
1793 	 */
1794 	entries1 = xfs_attr3_leaf_entryp(leaf1);
1795 	entries2 = xfs_attr3_leaf_entryp(leaf2);
1796 	blk1->hashval = be32_to_cpu(entries1[ichdr1.count - 1].hashval);
1797 	blk2->hashval = be32_to_cpu(entries2[ichdr2.count - 1].hashval);
1798 
1799 	/*
1800 	 * Adjust the expected index for insertion.
1801 	 * NOTE: this code depends on the (current) situation that the
1802 	 * second block was originally empty.
1803 	 *
1804 	 * If the insertion point moved to the 2nd block, we must adjust
1805 	 * the index.  We must also track the entry just following the
1806 	 * new entry for use in an "atomic rename" operation, that entry
1807 	 * is always the "old" entry and the "new" entry is what we are
1808 	 * inserting.  The index/blkno fields refer to the "old" entry,
1809 	 * while the index2/blkno2 fields refer to the "new" entry.
1810 	 */
1811 	if (blk1->index > ichdr1.count) {
1812 		ASSERT(state->inleaf == 0);
1813 		blk2->index = blk1->index - ichdr1.count;
1814 		args->index = args->index2 = blk2->index;
1815 		args->blkno = args->blkno2 = blk2->blkno;
1816 	} else if (blk1->index == ichdr1.count) {
1817 		if (state->inleaf) {
1818 			args->index = blk1->index;
1819 			args->blkno = blk1->blkno;
1820 			args->index2 = 0;
1821 			args->blkno2 = blk2->blkno;
1822 		} else {
1823 			/*
1824 			 * On a double leaf split, the original attr location
1825 			 * is already stored in blkno2/index2, so don't
1826 			 * overwrite it overwise we corrupt the tree.
1827 			 */
1828 			blk2->index = blk1->index - ichdr1.count;
1829 			args->index = blk2->index;
1830 			args->blkno = blk2->blkno;
1831 			if (!state->extravalid) {
1832 				/*
1833 				 * set the new attr location to match the old
1834 				 * one and let the higher level split code
1835 				 * decide where in the leaf to place it.
1836 				 */
1837 				args->index2 = blk2->index;
1838 				args->blkno2 = blk2->blkno;
1839 			}
1840 		}
1841 	} else {
1842 		ASSERT(state->inleaf == 1);
1843 		args->index = args->index2 = blk1->index;
1844 		args->blkno = args->blkno2 = blk1->blkno;
1845 	}
1846 }
1847 
1848 /*
1849  * Examine entries until we reduce the absolute difference in
1850  * byte usage between the two blocks to a minimum.
1851  * GROT: Is this really necessary?  With other than a 512 byte blocksize,
1852  * GROT: there will always be enough room in either block for a new entry.
1853  * GROT: Do a double-split for this case?
1854  */
1855 STATIC int
1856 xfs_attr3_leaf_figure_balance(
1857 	struct xfs_da_state		*state,
1858 	struct xfs_da_state_blk		*blk1,
1859 	struct xfs_attr3_icleaf_hdr	*ichdr1,
1860 	struct xfs_da_state_blk		*blk2,
1861 	struct xfs_attr3_icleaf_hdr	*ichdr2,
1862 	int				*countarg,
1863 	int				*usedbytesarg)
1864 {
1865 	struct xfs_attr_leafblock	*leaf1 = blk1->bp->b_addr;
1866 	struct xfs_attr_leafblock	*leaf2 = blk2->bp->b_addr;
1867 	struct xfs_attr_leaf_entry	*entry;
1868 	int				count;
1869 	int				max;
1870 	int				index;
1871 	int				totallen = 0;
1872 	int				half;
1873 	int				lastdelta;
1874 	int				foundit = 0;
1875 	int				tmp;
1876 
1877 	/*
1878 	 * Examine entries until we reduce the absolute difference in
1879 	 * byte usage between the two blocks to a minimum.
1880 	 */
1881 	max = ichdr1->count + ichdr2->count;
1882 	half = (max + 1) * sizeof(*entry);
1883 	half += ichdr1->usedbytes + ichdr2->usedbytes +
1884 			xfs_attr_leaf_newentsize(state->args, NULL);
1885 	half /= 2;
1886 	lastdelta = state->args->geo->blksize;
1887 	entry = xfs_attr3_leaf_entryp(leaf1);
1888 	for (count = index = 0; count < max; entry++, index++, count++) {
1889 
1890 #define XFS_ATTR_ABS(A)	(((A) < 0) ? -(A) : (A))
1891 		/*
1892 		 * The new entry is in the first block, account for it.
1893 		 */
1894 		if (count == blk1->index) {
1895 			tmp = totallen + sizeof(*entry) +
1896 				xfs_attr_leaf_newentsize(state->args, NULL);
1897 			if (XFS_ATTR_ABS(half - tmp) > lastdelta)
1898 				break;
1899 			lastdelta = XFS_ATTR_ABS(half - tmp);
1900 			totallen = tmp;
1901 			foundit = 1;
1902 		}
1903 
1904 		/*
1905 		 * Wrap around into the second block if necessary.
1906 		 */
1907 		if (count == ichdr1->count) {
1908 			leaf1 = leaf2;
1909 			entry = xfs_attr3_leaf_entryp(leaf1);
1910 			index = 0;
1911 		}
1912 
1913 		/*
1914 		 * Figure out if next leaf entry would be too much.
1915 		 */
1916 		tmp = totallen + sizeof(*entry) + xfs_attr_leaf_entsize(leaf1,
1917 									index);
1918 		if (XFS_ATTR_ABS(half - tmp) > lastdelta)
1919 			break;
1920 		lastdelta = XFS_ATTR_ABS(half - tmp);
1921 		totallen = tmp;
1922 #undef XFS_ATTR_ABS
1923 	}
1924 
1925 	/*
1926 	 * Calculate the number of usedbytes that will end up in lower block.
1927 	 * If new entry not in lower block, fix up the count.
1928 	 */
1929 	totallen -= count * sizeof(*entry);
1930 	if (foundit) {
1931 		totallen -= sizeof(*entry) +
1932 				xfs_attr_leaf_newentsize(state->args, NULL);
1933 	}
1934 
1935 	*countarg = count;
1936 	*usedbytesarg = totallen;
1937 	return foundit;
1938 }
1939 
1940 /*========================================================================
1941  * Routines used for shrinking the Btree.
1942  *========================================================================*/
1943 
1944 /*
1945  * Check a leaf block and its neighbors to see if the block should be
1946  * collapsed into one or the other neighbor.  Always keep the block
1947  * with the smaller block number.
1948  * If the current block is over 50% full, don't try to join it, return 0.
1949  * If the block is empty, fill in the state structure and return 2.
1950  * If it can be collapsed, fill in the state structure and return 1.
1951  * If nothing can be done, return 0.
1952  *
1953  * GROT: allow for INCOMPLETE entries in calculation.
1954  */
1955 int
1956 xfs_attr3_leaf_toosmall(
1957 	struct xfs_da_state	*state,
1958 	int			*action)
1959 {
1960 	struct xfs_attr_leafblock *leaf;
1961 	struct xfs_da_state_blk	*blk;
1962 	struct xfs_attr3_icleaf_hdr ichdr;
1963 	struct xfs_buf		*bp;
1964 	xfs_dablk_t		blkno;
1965 	int			bytes;
1966 	int			forward;
1967 	int			error;
1968 	int			retval;
1969 	int			i;
1970 
1971 	trace_xfs_attr_leaf_toosmall(state->args);
1972 
1973 	/*
1974 	 * Check for the degenerate case of the block being over 50% full.
1975 	 * If so, it's not worth even looking to see if we might be able
1976 	 * to coalesce with a sibling.
1977 	 */
1978 	blk = &state->path.blk[ state->path.active-1 ];
1979 	leaf = blk->bp->b_addr;
1980 	xfs_attr3_leaf_hdr_from_disk(state->args->geo, &ichdr, leaf);
1981 	bytes = xfs_attr3_leaf_hdr_size(leaf) +
1982 		ichdr.count * sizeof(xfs_attr_leaf_entry_t) +
1983 		ichdr.usedbytes;
1984 	if (bytes > (state->args->geo->blksize >> 1)) {
1985 		*action = 0;	/* blk over 50%, don't try to join */
1986 		return 0;
1987 	}
1988 
1989 	/*
1990 	 * Check for the degenerate case of the block being empty.
1991 	 * If the block is empty, we'll simply delete it, no need to
1992 	 * coalesce it with a sibling block.  We choose (arbitrarily)
1993 	 * to merge with the forward block unless it is NULL.
1994 	 */
1995 	if (ichdr.count == 0) {
1996 		/*
1997 		 * Make altpath point to the block we want to keep and
1998 		 * path point to the block we want to drop (this one).
1999 		 */
2000 		forward = (ichdr.forw != 0);
2001 		memcpy(&state->altpath, &state->path, sizeof(state->path));
2002 		error = xfs_da3_path_shift(state, &state->altpath, forward,
2003 						 0, &retval);
2004 		if (error)
2005 			return error;
2006 		if (retval) {
2007 			*action = 0;
2008 		} else {
2009 			*action = 2;
2010 		}
2011 		return 0;
2012 	}
2013 
2014 	/*
2015 	 * Examine each sibling block to see if we can coalesce with
2016 	 * at least 25% free space to spare.  We need to figure out
2017 	 * whether to merge with the forward or the backward block.
2018 	 * We prefer coalescing with the lower numbered sibling so as
2019 	 * to shrink an attribute list over time.
2020 	 */
2021 	/* start with smaller blk num */
2022 	forward = ichdr.forw < ichdr.back;
2023 	for (i = 0; i < 2; forward = !forward, i++) {
2024 		struct xfs_attr3_icleaf_hdr ichdr2;
2025 		if (forward)
2026 			blkno = ichdr.forw;
2027 		else
2028 			blkno = ichdr.back;
2029 		if (blkno == 0)
2030 			continue;
2031 		error = xfs_attr3_leaf_read(state->args->trans, state->args->dp,
2032 					blkno, &bp);
2033 		if (error)
2034 			return error;
2035 
2036 		xfs_attr3_leaf_hdr_from_disk(state->args->geo, &ichdr2, bp->b_addr);
2037 
2038 		bytes = state->args->geo->blksize -
2039 			(state->args->geo->blksize >> 2) -
2040 			ichdr.usedbytes - ichdr2.usedbytes -
2041 			((ichdr.count + ichdr2.count) *
2042 					sizeof(xfs_attr_leaf_entry_t)) -
2043 			xfs_attr3_leaf_hdr_size(leaf);
2044 
2045 		xfs_trans_brelse(state->args->trans, bp);
2046 		if (bytes >= 0)
2047 			break;	/* fits with at least 25% to spare */
2048 	}
2049 	if (i >= 2) {
2050 		*action = 0;
2051 		return 0;
2052 	}
2053 
2054 	/*
2055 	 * Make altpath point to the block we want to keep (the lower
2056 	 * numbered block) and path point to the block we want to drop.
2057 	 */
2058 	memcpy(&state->altpath, &state->path, sizeof(state->path));
2059 	if (blkno < blk->blkno) {
2060 		error = xfs_da3_path_shift(state, &state->altpath, forward,
2061 						 0, &retval);
2062 	} else {
2063 		error = xfs_da3_path_shift(state, &state->path, forward,
2064 						 0, &retval);
2065 	}
2066 	if (error)
2067 		return error;
2068 	if (retval) {
2069 		*action = 0;
2070 	} else {
2071 		*action = 1;
2072 	}
2073 	return 0;
2074 }
2075 
2076 /*
2077  * Remove a name from the leaf attribute list structure.
2078  *
2079  * Return 1 if leaf is less than 37% full, 0 if >= 37% full.
2080  * If two leaves are 37% full, when combined they will leave 25% free.
2081  */
2082 int
2083 xfs_attr3_leaf_remove(
2084 	struct xfs_buf		*bp,
2085 	struct xfs_da_args	*args)
2086 {
2087 	struct xfs_attr_leafblock *leaf;
2088 	struct xfs_attr3_icleaf_hdr ichdr;
2089 	struct xfs_attr_leaf_entry *entry;
2090 	int			before;
2091 	int			after;
2092 	int			smallest;
2093 	int			entsize;
2094 	int			tablesize;
2095 	int			tmp;
2096 	int			i;
2097 
2098 	trace_xfs_attr_leaf_remove(args);
2099 
2100 	leaf = bp->b_addr;
2101 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
2102 
2103 	ASSERT(ichdr.count > 0 && ichdr.count < args->geo->blksize / 8);
2104 	ASSERT(args->index >= 0 && args->index < ichdr.count);
2105 	ASSERT(ichdr.firstused >= ichdr.count * sizeof(*entry) +
2106 					xfs_attr3_leaf_hdr_size(leaf));
2107 
2108 	entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
2109 
2110 	ASSERT(be16_to_cpu(entry->nameidx) >= ichdr.firstused);
2111 	ASSERT(be16_to_cpu(entry->nameidx) < args->geo->blksize);
2112 
2113 	/*
2114 	 * Scan through free region table:
2115 	 *    check for adjacency of free'd entry with an existing one,
2116 	 *    find smallest free region in case we need to replace it,
2117 	 *    adjust any map that borders the entry table,
2118 	 */
2119 	tablesize = ichdr.count * sizeof(xfs_attr_leaf_entry_t)
2120 					+ xfs_attr3_leaf_hdr_size(leaf);
2121 	tmp = ichdr.freemap[0].size;
2122 	before = after = -1;
2123 	smallest = XFS_ATTR_LEAF_MAPSIZE - 1;
2124 	entsize = xfs_attr_leaf_entsize(leaf, args->index);
2125 	for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
2126 		ASSERT(ichdr.freemap[i].base < args->geo->blksize);
2127 		ASSERT(ichdr.freemap[i].size < args->geo->blksize);
2128 		if (ichdr.freemap[i].base == tablesize) {
2129 			ichdr.freemap[i].base -= sizeof(xfs_attr_leaf_entry_t);
2130 			ichdr.freemap[i].size += sizeof(xfs_attr_leaf_entry_t);
2131 		}
2132 
2133 		if (ichdr.freemap[i].base + ichdr.freemap[i].size ==
2134 				be16_to_cpu(entry->nameidx)) {
2135 			before = i;
2136 		} else if (ichdr.freemap[i].base ==
2137 				(be16_to_cpu(entry->nameidx) + entsize)) {
2138 			after = i;
2139 		} else if (ichdr.freemap[i].size < tmp) {
2140 			tmp = ichdr.freemap[i].size;
2141 			smallest = i;
2142 		}
2143 	}
2144 
2145 	/*
2146 	 * Coalesce adjacent freemap regions,
2147 	 * or replace the smallest region.
2148 	 */
2149 	if ((before >= 0) || (after >= 0)) {
2150 		if ((before >= 0) && (after >= 0)) {
2151 			ichdr.freemap[before].size += entsize;
2152 			ichdr.freemap[before].size += ichdr.freemap[after].size;
2153 			ichdr.freemap[after].base = 0;
2154 			ichdr.freemap[after].size = 0;
2155 		} else if (before >= 0) {
2156 			ichdr.freemap[before].size += entsize;
2157 		} else {
2158 			ichdr.freemap[after].base = be16_to_cpu(entry->nameidx);
2159 			ichdr.freemap[after].size += entsize;
2160 		}
2161 	} else {
2162 		/*
2163 		 * Replace smallest region (if it is smaller than free'd entry)
2164 		 */
2165 		if (ichdr.freemap[smallest].size < entsize) {
2166 			ichdr.freemap[smallest].base = be16_to_cpu(entry->nameidx);
2167 			ichdr.freemap[smallest].size = entsize;
2168 		}
2169 	}
2170 
2171 	/*
2172 	 * Did we remove the first entry?
2173 	 */
2174 	if (be16_to_cpu(entry->nameidx) == ichdr.firstused)
2175 		smallest = 1;
2176 	else
2177 		smallest = 0;
2178 
2179 	/*
2180 	 * Compress the remaining entries and zero out the removed stuff.
2181 	 */
2182 	memset(xfs_attr3_leaf_name(leaf, args->index), 0, entsize);
2183 	ichdr.usedbytes -= entsize;
2184 	xfs_trans_log_buf(args->trans, bp,
2185 	     XFS_DA_LOGRANGE(leaf, xfs_attr3_leaf_name(leaf, args->index),
2186 				   entsize));
2187 
2188 	tmp = (ichdr.count - args->index) * sizeof(xfs_attr_leaf_entry_t);
2189 	memmove(entry, entry + 1, tmp);
2190 	ichdr.count--;
2191 	xfs_trans_log_buf(args->trans, bp,
2192 	    XFS_DA_LOGRANGE(leaf, entry, tmp + sizeof(xfs_attr_leaf_entry_t)));
2193 
2194 	entry = &xfs_attr3_leaf_entryp(leaf)[ichdr.count];
2195 	memset(entry, 0, sizeof(xfs_attr_leaf_entry_t));
2196 
2197 	/*
2198 	 * If we removed the first entry, re-find the first used byte
2199 	 * in the name area.  Note that if the entry was the "firstused",
2200 	 * then we don't have a "hole" in our block resulting from
2201 	 * removing the name.
2202 	 */
2203 	if (smallest) {
2204 		tmp = args->geo->blksize;
2205 		entry = xfs_attr3_leaf_entryp(leaf);
2206 		for (i = ichdr.count - 1; i >= 0; entry++, i--) {
2207 			ASSERT(be16_to_cpu(entry->nameidx) >= ichdr.firstused);
2208 			ASSERT(be16_to_cpu(entry->nameidx) < args->geo->blksize);
2209 
2210 			if (be16_to_cpu(entry->nameidx) < tmp)
2211 				tmp = be16_to_cpu(entry->nameidx);
2212 		}
2213 		ichdr.firstused = tmp;
2214 		ASSERT(ichdr.firstused != 0);
2215 	} else {
2216 		ichdr.holes = 1;	/* mark as needing compaction */
2217 	}
2218 	xfs_attr3_leaf_hdr_to_disk(args->geo, leaf, &ichdr);
2219 	xfs_trans_log_buf(args->trans, bp,
2220 			  XFS_DA_LOGRANGE(leaf, &leaf->hdr,
2221 					  xfs_attr3_leaf_hdr_size(leaf)));
2222 
2223 	/*
2224 	 * Check if leaf is less than 50% full, caller may want to
2225 	 * "join" the leaf with a sibling if so.
2226 	 */
2227 	tmp = ichdr.usedbytes + xfs_attr3_leaf_hdr_size(leaf) +
2228 	      ichdr.count * sizeof(xfs_attr_leaf_entry_t);
2229 
2230 	return tmp < args->geo->magicpct; /* leaf is < 37% full */
2231 }
2232 
2233 /*
2234  * Move all the attribute list entries from drop_leaf into save_leaf.
2235  */
2236 void
2237 xfs_attr3_leaf_unbalance(
2238 	struct xfs_da_state	*state,
2239 	struct xfs_da_state_blk	*drop_blk,
2240 	struct xfs_da_state_blk	*save_blk)
2241 {
2242 	struct xfs_attr_leafblock *drop_leaf = drop_blk->bp->b_addr;
2243 	struct xfs_attr_leafblock *save_leaf = save_blk->bp->b_addr;
2244 	struct xfs_attr3_icleaf_hdr drophdr;
2245 	struct xfs_attr3_icleaf_hdr savehdr;
2246 	struct xfs_attr_leaf_entry *entry;
2247 
2248 	trace_xfs_attr_leaf_unbalance(state->args);
2249 
2250 	drop_leaf = drop_blk->bp->b_addr;
2251 	save_leaf = save_blk->bp->b_addr;
2252 	xfs_attr3_leaf_hdr_from_disk(state->args->geo, &drophdr, drop_leaf);
2253 	xfs_attr3_leaf_hdr_from_disk(state->args->geo, &savehdr, save_leaf);
2254 	entry = xfs_attr3_leaf_entryp(drop_leaf);
2255 
2256 	/*
2257 	 * Save last hashval from dying block for later Btree fixup.
2258 	 */
2259 	drop_blk->hashval = be32_to_cpu(entry[drophdr.count - 1].hashval);
2260 
2261 	/*
2262 	 * Check if we need a temp buffer, or can we do it in place.
2263 	 * Note that we don't check "leaf" for holes because we will
2264 	 * always be dropping it, toosmall() decided that for us already.
2265 	 */
2266 	if (savehdr.holes == 0) {
2267 		/*
2268 		 * dest leaf has no holes, so we add there.  May need
2269 		 * to make some room in the entry array.
2270 		 */
2271 		if (xfs_attr3_leaf_order(save_blk->bp, &savehdr,
2272 					 drop_blk->bp, &drophdr)) {
2273 			xfs_attr3_leaf_moveents(state->args,
2274 						drop_leaf, &drophdr, 0,
2275 						save_leaf, &savehdr, 0,
2276 						drophdr.count);
2277 		} else {
2278 			xfs_attr3_leaf_moveents(state->args,
2279 						drop_leaf, &drophdr, 0,
2280 						save_leaf, &savehdr,
2281 						savehdr.count, drophdr.count);
2282 		}
2283 	} else {
2284 		/*
2285 		 * Destination has holes, so we make a temporary copy
2286 		 * of the leaf and add them both to that.
2287 		 */
2288 		struct xfs_attr_leafblock *tmp_leaf;
2289 		struct xfs_attr3_icleaf_hdr tmphdr;
2290 
2291 		tmp_leaf = kmem_zalloc(state->args->geo->blksize, 0);
2292 
2293 		/*
2294 		 * Copy the header into the temp leaf so that all the stuff
2295 		 * not in the incore header is present and gets copied back in
2296 		 * once we've moved all the entries.
2297 		 */
2298 		memcpy(tmp_leaf, save_leaf, xfs_attr3_leaf_hdr_size(save_leaf));
2299 
2300 		memset(&tmphdr, 0, sizeof(tmphdr));
2301 		tmphdr.magic = savehdr.magic;
2302 		tmphdr.forw = savehdr.forw;
2303 		tmphdr.back = savehdr.back;
2304 		tmphdr.firstused = state->args->geo->blksize;
2305 
2306 		/* write the header to the temp buffer to initialise it */
2307 		xfs_attr3_leaf_hdr_to_disk(state->args->geo, tmp_leaf, &tmphdr);
2308 
2309 		if (xfs_attr3_leaf_order(save_blk->bp, &savehdr,
2310 					 drop_blk->bp, &drophdr)) {
2311 			xfs_attr3_leaf_moveents(state->args,
2312 						drop_leaf, &drophdr, 0,
2313 						tmp_leaf, &tmphdr, 0,
2314 						drophdr.count);
2315 			xfs_attr3_leaf_moveents(state->args,
2316 						save_leaf, &savehdr, 0,
2317 						tmp_leaf, &tmphdr, tmphdr.count,
2318 						savehdr.count);
2319 		} else {
2320 			xfs_attr3_leaf_moveents(state->args,
2321 						save_leaf, &savehdr, 0,
2322 						tmp_leaf, &tmphdr, 0,
2323 						savehdr.count);
2324 			xfs_attr3_leaf_moveents(state->args,
2325 						drop_leaf, &drophdr, 0,
2326 						tmp_leaf, &tmphdr, tmphdr.count,
2327 						drophdr.count);
2328 		}
2329 		memcpy(save_leaf, tmp_leaf, state->args->geo->blksize);
2330 		savehdr = tmphdr; /* struct copy */
2331 		kmem_free(tmp_leaf);
2332 	}
2333 
2334 	xfs_attr3_leaf_hdr_to_disk(state->args->geo, save_leaf, &savehdr);
2335 	xfs_trans_log_buf(state->args->trans, save_blk->bp, 0,
2336 					   state->args->geo->blksize - 1);
2337 
2338 	/*
2339 	 * Copy out last hashval in each block for B-tree code.
2340 	 */
2341 	entry = xfs_attr3_leaf_entryp(save_leaf);
2342 	save_blk->hashval = be32_to_cpu(entry[savehdr.count - 1].hashval);
2343 }
2344 
2345 /*========================================================================
2346  * Routines used for finding things in the Btree.
2347  *========================================================================*/
2348 
2349 /*
2350  * Look up a name in a leaf attribute list structure.
2351  * This is the internal routine, it uses the caller's buffer.
2352  *
2353  * Note that duplicate keys are allowed, but only check within the
2354  * current leaf node.  The Btree code must check in adjacent leaf nodes.
2355  *
2356  * Return in args->index the index into the entry[] array of either
2357  * the found entry, or where the entry should have been (insert before
2358  * that entry).
2359  *
2360  * Don't change the args->value unless we find the attribute.
2361  */
2362 int
2363 xfs_attr3_leaf_lookup_int(
2364 	struct xfs_buf		*bp,
2365 	struct xfs_da_args	*args)
2366 {
2367 	struct xfs_attr_leafblock *leaf;
2368 	struct xfs_attr3_icleaf_hdr ichdr;
2369 	struct xfs_attr_leaf_entry *entry;
2370 	struct xfs_attr_leaf_entry *entries;
2371 	struct xfs_attr_leaf_name_local *name_loc;
2372 	struct xfs_attr_leaf_name_remote *name_rmt;
2373 	xfs_dahash_t		hashval;
2374 	int			probe;
2375 	int			span;
2376 
2377 	trace_xfs_attr_leaf_lookup(args);
2378 
2379 	leaf = bp->b_addr;
2380 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
2381 	entries = xfs_attr3_leaf_entryp(leaf);
2382 	if (ichdr.count >= args->geo->blksize / 8) {
2383 		xfs_buf_mark_corrupt(bp);
2384 		return -EFSCORRUPTED;
2385 	}
2386 
2387 	/*
2388 	 * Binary search.  (note: small blocks will skip this loop)
2389 	 */
2390 	hashval = args->hashval;
2391 	probe = span = ichdr.count / 2;
2392 	for (entry = &entries[probe]; span > 4; entry = &entries[probe]) {
2393 		span /= 2;
2394 		if (be32_to_cpu(entry->hashval) < hashval)
2395 			probe += span;
2396 		else if (be32_to_cpu(entry->hashval) > hashval)
2397 			probe -= span;
2398 		else
2399 			break;
2400 	}
2401 	if (!(probe >= 0 && (!ichdr.count || probe < ichdr.count))) {
2402 		xfs_buf_mark_corrupt(bp);
2403 		return -EFSCORRUPTED;
2404 	}
2405 	if (!(span <= 4 || be32_to_cpu(entry->hashval) == hashval)) {
2406 		xfs_buf_mark_corrupt(bp);
2407 		return -EFSCORRUPTED;
2408 	}
2409 
2410 	/*
2411 	 * Since we may have duplicate hashval's, find the first matching
2412 	 * hashval in the leaf.
2413 	 */
2414 	while (probe > 0 && be32_to_cpu(entry->hashval) >= hashval) {
2415 		entry--;
2416 		probe--;
2417 	}
2418 	while (probe < ichdr.count &&
2419 	       be32_to_cpu(entry->hashval) < hashval) {
2420 		entry++;
2421 		probe++;
2422 	}
2423 	if (probe == ichdr.count || be32_to_cpu(entry->hashval) != hashval) {
2424 		args->index = probe;
2425 		return -ENOATTR;
2426 	}
2427 
2428 	/*
2429 	 * Duplicate keys may be present, so search all of them for a match.
2430 	 */
2431 	for (; probe < ichdr.count && (be32_to_cpu(entry->hashval) == hashval);
2432 			entry++, probe++) {
2433 /*
2434  * GROT: Add code to remove incomplete entries.
2435  */
2436 		if (entry->flags & XFS_ATTR_LOCAL) {
2437 			name_loc = xfs_attr3_leaf_name_local(leaf, probe);
2438 			if (!xfs_attr_match(args, name_loc->namelen,
2439 					name_loc->nameval, entry->flags))
2440 				continue;
2441 			args->index = probe;
2442 			return -EEXIST;
2443 		} else {
2444 			name_rmt = xfs_attr3_leaf_name_remote(leaf, probe);
2445 			if (!xfs_attr_match(args, name_rmt->namelen,
2446 					name_rmt->name, entry->flags))
2447 				continue;
2448 			args->index = probe;
2449 			args->rmtvaluelen = be32_to_cpu(name_rmt->valuelen);
2450 			args->rmtblkno = be32_to_cpu(name_rmt->valueblk);
2451 			args->rmtblkcnt = xfs_attr3_rmt_blocks(
2452 							args->dp->i_mount,
2453 							args->rmtvaluelen);
2454 			return -EEXIST;
2455 		}
2456 	}
2457 	args->index = probe;
2458 	return -ENOATTR;
2459 }
2460 
2461 /*
2462  * Get the value associated with an attribute name from a leaf attribute
2463  * list structure.
2464  *
2465  * If args->valuelen is zero, only the length needs to be returned.  Unlike a
2466  * lookup, we only return an error if the attribute does not exist or we can't
2467  * retrieve the value.
2468  */
2469 int
2470 xfs_attr3_leaf_getvalue(
2471 	struct xfs_buf		*bp,
2472 	struct xfs_da_args	*args)
2473 {
2474 	struct xfs_attr_leafblock *leaf;
2475 	struct xfs_attr3_icleaf_hdr ichdr;
2476 	struct xfs_attr_leaf_entry *entry;
2477 	struct xfs_attr_leaf_name_local *name_loc;
2478 	struct xfs_attr_leaf_name_remote *name_rmt;
2479 
2480 	leaf = bp->b_addr;
2481 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
2482 	ASSERT(ichdr.count < args->geo->blksize / 8);
2483 	ASSERT(args->index < ichdr.count);
2484 
2485 	entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
2486 	if (entry->flags & XFS_ATTR_LOCAL) {
2487 		name_loc = xfs_attr3_leaf_name_local(leaf, args->index);
2488 		ASSERT(name_loc->namelen == args->namelen);
2489 		ASSERT(memcmp(args->name, name_loc->nameval, args->namelen) == 0);
2490 		return xfs_attr_copy_value(args,
2491 					&name_loc->nameval[args->namelen],
2492 					be16_to_cpu(name_loc->valuelen));
2493 	}
2494 
2495 	name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
2496 	ASSERT(name_rmt->namelen == args->namelen);
2497 	ASSERT(memcmp(args->name, name_rmt->name, args->namelen) == 0);
2498 	args->rmtvaluelen = be32_to_cpu(name_rmt->valuelen);
2499 	args->rmtblkno = be32_to_cpu(name_rmt->valueblk);
2500 	args->rmtblkcnt = xfs_attr3_rmt_blocks(args->dp->i_mount,
2501 					       args->rmtvaluelen);
2502 	return xfs_attr_copy_value(args, NULL, args->rmtvaluelen);
2503 }
2504 
2505 /*========================================================================
2506  * Utility routines.
2507  *========================================================================*/
2508 
2509 /*
2510  * Move the indicated entries from one leaf to another.
2511  * NOTE: this routine modifies both source and destination leaves.
2512  */
2513 /*ARGSUSED*/
2514 STATIC void
2515 xfs_attr3_leaf_moveents(
2516 	struct xfs_da_args		*args,
2517 	struct xfs_attr_leafblock	*leaf_s,
2518 	struct xfs_attr3_icleaf_hdr	*ichdr_s,
2519 	int				start_s,
2520 	struct xfs_attr_leafblock	*leaf_d,
2521 	struct xfs_attr3_icleaf_hdr	*ichdr_d,
2522 	int				start_d,
2523 	int				count)
2524 {
2525 	struct xfs_attr_leaf_entry	*entry_s;
2526 	struct xfs_attr_leaf_entry	*entry_d;
2527 	int				desti;
2528 	int				tmp;
2529 	int				i;
2530 
2531 	/*
2532 	 * Check for nothing to do.
2533 	 */
2534 	if (count == 0)
2535 		return;
2536 
2537 	/*
2538 	 * Set up environment.
2539 	 */
2540 	ASSERT(ichdr_s->magic == XFS_ATTR_LEAF_MAGIC ||
2541 	       ichdr_s->magic == XFS_ATTR3_LEAF_MAGIC);
2542 	ASSERT(ichdr_s->magic == ichdr_d->magic);
2543 	ASSERT(ichdr_s->count > 0 && ichdr_s->count < args->geo->blksize / 8);
2544 	ASSERT(ichdr_s->firstused >= (ichdr_s->count * sizeof(*entry_s))
2545 					+ xfs_attr3_leaf_hdr_size(leaf_s));
2546 	ASSERT(ichdr_d->count < args->geo->blksize / 8);
2547 	ASSERT(ichdr_d->firstused >= (ichdr_d->count * sizeof(*entry_d))
2548 					+ xfs_attr3_leaf_hdr_size(leaf_d));
2549 
2550 	ASSERT(start_s < ichdr_s->count);
2551 	ASSERT(start_d <= ichdr_d->count);
2552 	ASSERT(count <= ichdr_s->count);
2553 
2554 
2555 	/*
2556 	 * Move the entries in the destination leaf up to make a hole?
2557 	 */
2558 	if (start_d < ichdr_d->count) {
2559 		tmp  = ichdr_d->count - start_d;
2560 		tmp *= sizeof(xfs_attr_leaf_entry_t);
2561 		entry_s = &xfs_attr3_leaf_entryp(leaf_d)[start_d];
2562 		entry_d = &xfs_attr3_leaf_entryp(leaf_d)[start_d + count];
2563 		memmove(entry_d, entry_s, tmp);
2564 	}
2565 
2566 	/*
2567 	 * Copy all entry's in the same (sorted) order,
2568 	 * but allocate attribute info packed and in sequence.
2569 	 */
2570 	entry_s = &xfs_attr3_leaf_entryp(leaf_s)[start_s];
2571 	entry_d = &xfs_attr3_leaf_entryp(leaf_d)[start_d];
2572 	desti = start_d;
2573 	for (i = 0; i < count; entry_s++, entry_d++, desti++, i++) {
2574 		ASSERT(be16_to_cpu(entry_s->nameidx) >= ichdr_s->firstused);
2575 		tmp = xfs_attr_leaf_entsize(leaf_s, start_s + i);
2576 #ifdef GROT
2577 		/*
2578 		 * Code to drop INCOMPLETE entries.  Difficult to use as we
2579 		 * may also need to change the insertion index.  Code turned
2580 		 * off for 6.2, should be revisited later.
2581 		 */
2582 		if (entry_s->flags & XFS_ATTR_INCOMPLETE) { /* skip partials? */
2583 			memset(xfs_attr3_leaf_name(leaf_s, start_s + i), 0, tmp);
2584 			ichdr_s->usedbytes -= tmp;
2585 			ichdr_s->count -= 1;
2586 			entry_d--;	/* to compensate for ++ in loop hdr */
2587 			desti--;
2588 			if ((start_s + i) < offset)
2589 				result++;	/* insertion index adjustment */
2590 		} else {
2591 #endif /* GROT */
2592 			ichdr_d->firstused -= tmp;
2593 			/* both on-disk, don't endian flip twice */
2594 			entry_d->hashval = entry_s->hashval;
2595 			entry_d->nameidx = cpu_to_be16(ichdr_d->firstused);
2596 			entry_d->flags = entry_s->flags;
2597 			ASSERT(be16_to_cpu(entry_d->nameidx) + tmp
2598 							<= args->geo->blksize);
2599 			memmove(xfs_attr3_leaf_name(leaf_d, desti),
2600 				xfs_attr3_leaf_name(leaf_s, start_s + i), tmp);
2601 			ASSERT(be16_to_cpu(entry_s->nameidx) + tmp
2602 							<= args->geo->blksize);
2603 			memset(xfs_attr3_leaf_name(leaf_s, start_s + i), 0, tmp);
2604 			ichdr_s->usedbytes -= tmp;
2605 			ichdr_d->usedbytes += tmp;
2606 			ichdr_s->count -= 1;
2607 			ichdr_d->count += 1;
2608 			tmp = ichdr_d->count * sizeof(xfs_attr_leaf_entry_t)
2609 					+ xfs_attr3_leaf_hdr_size(leaf_d);
2610 			ASSERT(ichdr_d->firstused >= tmp);
2611 #ifdef GROT
2612 		}
2613 #endif /* GROT */
2614 	}
2615 
2616 	/*
2617 	 * Zero out the entries we just copied.
2618 	 */
2619 	if (start_s == ichdr_s->count) {
2620 		tmp = count * sizeof(xfs_attr_leaf_entry_t);
2621 		entry_s = &xfs_attr3_leaf_entryp(leaf_s)[start_s];
2622 		ASSERT(((char *)entry_s + tmp) <=
2623 		       ((char *)leaf_s + args->geo->blksize));
2624 		memset(entry_s, 0, tmp);
2625 	} else {
2626 		/*
2627 		 * Move the remaining entries down to fill the hole,
2628 		 * then zero the entries at the top.
2629 		 */
2630 		tmp  = (ichdr_s->count - count) * sizeof(xfs_attr_leaf_entry_t);
2631 		entry_s = &xfs_attr3_leaf_entryp(leaf_s)[start_s + count];
2632 		entry_d = &xfs_attr3_leaf_entryp(leaf_s)[start_s];
2633 		memmove(entry_d, entry_s, tmp);
2634 
2635 		tmp = count * sizeof(xfs_attr_leaf_entry_t);
2636 		entry_s = &xfs_attr3_leaf_entryp(leaf_s)[ichdr_s->count];
2637 		ASSERT(((char *)entry_s + tmp) <=
2638 		       ((char *)leaf_s + args->geo->blksize));
2639 		memset(entry_s, 0, tmp);
2640 	}
2641 
2642 	/*
2643 	 * Fill in the freemap information
2644 	 */
2645 	ichdr_d->freemap[0].base = xfs_attr3_leaf_hdr_size(leaf_d);
2646 	ichdr_d->freemap[0].base += ichdr_d->count * sizeof(xfs_attr_leaf_entry_t);
2647 	ichdr_d->freemap[0].size = ichdr_d->firstused - ichdr_d->freemap[0].base;
2648 	ichdr_d->freemap[1].base = 0;
2649 	ichdr_d->freemap[2].base = 0;
2650 	ichdr_d->freemap[1].size = 0;
2651 	ichdr_d->freemap[2].size = 0;
2652 	ichdr_s->holes = 1;	/* leaf may not be compact */
2653 }
2654 
2655 /*
2656  * Pick up the last hashvalue from a leaf block.
2657  */
2658 xfs_dahash_t
2659 xfs_attr_leaf_lasthash(
2660 	struct xfs_buf	*bp,
2661 	int		*count)
2662 {
2663 	struct xfs_attr3_icleaf_hdr ichdr;
2664 	struct xfs_attr_leaf_entry *entries;
2665 	struct xfs_mount *mp = bp->b_mount;
2666 
2667 	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, bp->b_addr);
2668 	entries = xfs_attr3_leaf_entryp(bp->b_addr);
2669 	if (count)
2670 		*count = ichdr.count;
2671 	if (!ichdr.count)
2672 		return 0;
2673 	return be32_to_cpu(entries[ichdr.count - 1].hashval);
2674 }
2675 
2676 /*
2677  * Calculate the number of bytes used to store the indicated attribute
2678  * (whether local or remote only calculate bytes in this block).
2679  */
2680 STATIC int
2681 xfs_attr_leaf_entsize(xfs_attr_leafblock_t *leaf, int index)
2682 {
2683 	struct xfs_attr_leaf_entry *entries;
2684 	xfs_attr_leaf_name_local_t *name_loc;
2685 	xfs_attr_leaf_name_remote_t *name_rmt;
2686 	int size;
2687 
2688 	entries = xfs_attr3_leaf_entryp(leaf);
2689 	if (entries[index].flags & XFS_ATTR_LOCAL) {
2690 		name_loc = xfs_attr3_leaf_name_local(leaf, index);
2691 		size = xfs_attr_leaf_entsize_local(name_loc->namelen,
2692 						   be16_to_cpu(name_loc->valuelen));
2693 	} else {
2694 		name_rmt = xfs_attr3_leaf_name_remote(leaf, index);
2695 		size = xfs_attr_leaf_entsize_remote(name_rmt->namelen);
2696 	}
2697 	return size;
2698 }
2699 
2700 /*
2701  * Calculate the number of bytes that would be required to store the new
2702  * attribute (whether local or remote only calculate bytes in this block).
2703  * This routine decides as a side effect whether the attribute will be
2704  * a "local" or a "remote" attribute.
2705  */
2706 int
2707 xfs_attr_leaf_newentsize(
2708 	struct xfs_da_args	*args,
2709 	int			*local)
2710 {
2711 	int			size;
2712 
2713 	size = xfs_attr_leaf_entsize_local(args->namelen, args->valuelen);
2714 	if (size < xfs_attr_leaf_entsize_local_max(args->geo->blksize)) {
2715 		if (local)
2716 			*local = 1;
2717 		return size;
2718 	}
2719 	if (local)
2720 		*local = 0;
2721 	return xfs_attr_leaf_entsize_remote(args->namelen);
2722 }
2723 
2724 
2725 /*========================================================================
2726  * Manage the INCOMPLETE flag in a leaf entry
2727  *========================================================================*/
2728 
2729 /*
2730  * Clear the INCOMPLETE flag on an entry in a leaf block.
2731  */
2732 int
2733 xfs_attr3_leaf_clearflag(
2734 	struct xfs_da_args	*args)
2735 {
2736 	struct xfs_attr_leafblock *leaf;
2737 	struct xfs_attr_leaf_entry *entry;
2738 	struct xfs_attr_leaf_name_remote *name_rmt;
2739 	struct xfs_buf		*bp;
2740 	int			error;
2741 #ifdef DEBUG
2742 	struct xfs_attr3_icleaf_hdr ichdr;
2743 	xfs_attr_leaf_name_local_t *name_loc;
2744 	int namelen;
2745 	char *name;
2746 #endif /* DEBUG */
2747 
2748 	trace_xfs_attr_leaf_clearflag(args);
2749 	/*
2750 	 * Set up the operation.
2751 	 */
2752 	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, &bp);
2753 	if (error)
2754 		return error;
2755 
2756 	leaf = bp->b_addr;
2757 	entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
2758 	ASSERT(entry->flags & XFS_ATTR_INCOMPLETE);
2759 
2760 #ifdef DEBUG
2761 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
2762 	ASSERT(args->index < ichdr.count);
2763 	ASSERT(args->index >= 0);
2764 
2765 	if (entry->flags & XFS_ATTR_LOCAL) {
2766 		name_loc = xfs_attr3_leaf_name_local(leaf, args->index);
2767 		namelen = name_loc->namelen;
2768 		name = (char *)name_loc->nameval;
2769 	} else {
2770 		name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
2771 		namelen = name_rmt->namelen;
2772 		name = (char *)name_rmt->name;
2773 	}
2774 	ASSERT(be32_to_cpu(entry->hashval) == args->hashval);
2775 	ASSERT(namelen == args->namelen);
2776 	ASSERT(memcmp(name, args->name, namelen) == 0);
2777 #endif /* DEBUG */
2778 
2779 	entry->flags &= ~XFS_ATTR_INCOMPLETE;
2780 	xfs_trans_log_buf(args->trans, bp,
2781 			 XFS_DA_LOGRANGE(leaf, entry, sizeof(*entry)));
2782 
2783 	if (args->rmtblkno) {
2784 		ASSERT((entry->flags & XFS_ATTR_LOCAL) == 0);
2785 		name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
2786 		name_rmt->valueblk = cpu_to_be32(args->rmtblkno);
2787 		name_rmt->valuelen = cpu_to_be32(args->rmtvaluelen);
2788 		xfs_trans_log_buf(args->trans, bp,
2789 			 XFS_DA_LOGRANGE(leaf, name_rmt, sizeof(*name_rmt)));
2790 	}
2791 
2792 	return 0;
2793 }
2794 
2795 /*
2796  * Set the INCOMPLETE flag on an entry in a leaf block.
2797  */
2798 int
2799 xfs_attr3_leaf_setflag(
2800 	struct xfs_da_args	*args)
2801 {
2802 	struct xfs_attr_leafblock *leaf;
2803 	struct xfs_attr_leaf_entry *entry;
2804 	struct xfs_attr_leaf_name_remote *name_rmt;
2805 	struct xfs_buf		*bp;
2806 	int error;
2807 #ifdef DEBUG
2808 	struct xfs_attr3_icleaf_hdr ichdr;
2809 #endif
2810 
2811 	trace_xfs_attr_leaf_setflag(args);
2812 
2813 	/*
2814 	 * Set up the operation.
2815 	 */
2816 	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, &bp);
2817 	if (error)
2818 		return error;
2819 
2820 	leaf = bp->b_addr;
2821 #ifdef DEBUG
2822 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
2823 	ASSERT(args->index < ichdr.count);
2824 	ASSERT(args->index >= 0);
2825 #endif
2826 	entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
2827 
2828 	ASSERT((entry->flags & XFS_ATTR_INCOMPLETE) == 0);
2829 	entry->flags |= XFS_ATTR_INCOMPLETE;
2830 	xfs_trans_log_buf(args->trans, bp,
2831 			XFS_DA_LOGRANGE(leaf, entry, sizeof(*entry)));
2832 	if ((entry->flags & XFS_ATTR_LOCAL) == 0) {
2833 		name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
2834 		name_rmt->valueblk = 0;
2835 		name_rmt->valuelen = 0;
2836 		xfs_trans_log_buf(args->trans, bp,
2837 			 XFS_DA_LOGRANGE(leaf, name_rmt, sizeof(*name_rmt)));
2838 	}
2839 
2840 	return 0;
2841 }
2842 
2843 /*
2844  * In a single transaction, clear the INCOMPLETE flag on the leaf entry
2845  * given by args->blkno/index and set the INCOMPLETE flag on the leaf
2846  * entry given by args->blkno2/index2.
2847  *
2848  * Note that they could be in different blocks, or in the same block.
2849  */
2850 int
2851 xfs_attr3_leaf_flipflags(
2852 	struct xfs_da_args	*args)
2853 {
2854 	struct xfs_attr_leafblock *leaf1;
2855 	struct xfs_attr_leafblock *leaf2;
2856 	struct xfs_attr_leaf_entry *entry1;
2857 	struct xfs_attr_leaf_entry *entry2;
2858 	struct xfs_attr_leaf_name_remote *name_rmt;
2859 	struct xfs_buf		*bp1;
2860 	struct xfs_buf		*bp2;
2861 	int error;
2862 #ifdef DEBUG
2863 	struct xfs_attr3_icleaf_hdr ichdr1;
2864 	struct xfs_attr3_icleaf_hdr ichdr2;
2865 	xfs_attr_leaf_name_local_t *name_loc;
2866 	int namelen1, namelen2;
2867 	char *name1, *name2;
2868 #endif /* DEBUG */
2869 
2870 	trace_xfs_attr_leaf_flipflags(args);
2871 
2872 	/*
2873 	 * Read the block containing the "old" attr
2874 	 */
2875 	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, &bp1);
2876 	if (error)
2877 		return error;
2878 
2879 	/*
2880 	 * Read the block containing the "new" attr, if it is different
2881 	 */
2882 	if (args->blkno2 != args->blkno) {
2883 		error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno2,
2884 					   &bp2);
2885 		if (error)
2886 			return error;
2887 	} else {
2888 		bp2 = bp1;
2889 	}
2890 
2891 	leaf1 = bp1->b_addr;
2892 	entry1 = &xfs_attr3_leaf_entryp(leaf1)[args->index];
2893 
2894 	leaf2 = bp2->b_addr;
2895 	entry2 = &xfs_attr3_leaf_entryp(leaf2)[args->index2];
2896 
2897 #ifdef DEBUG
2898 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr1, leaf1);
2899 	ASSERT(args->index < ichdr1.count);
2900 	ASSERT(args->index >= 0);
2901 
2902 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr2, leaf2);
2903 	ASSERT(args->index2 < ichdr2.count);
2904 	ASSERT(args->index2 >= 0);
2905 
2906 	if (entry1->flags & XFS_ATTR_LOCAL) {
2907 		name_loc = xfs_attr3_leaf_name_local(leaf1, args->index);
2908 		namelen1 = name_loc->namelen;
2909 		name1 = (char *)name_loc->nameval;
2910 	} else {
2911 		name_rmt = xfs_attr3_leaf_name_remote(leaf1, args->index);
2912 		namelen1 = name_rmt->namelen;
2913 		name1 = (char *)name_rmt->name;
2914 	}
2915 	if (entry2->flags & XFS_ATTR_LOCAL) {
2916 		name_loc = xfs_attr3_leaf_name_local(leaf2, args->index2);
2917 		namelen2 = name_loc->namelen;
2918 		name2 = (char *)name_loc->nameval;
2919 	} else {
2920 		name_rmt = xfs_attr3_leaf_name_remote(leaf2, args->index2);
2921 		namelen2 = name_rmt->namelen;
2922 		name2 = (char *)name_rmt->name;
2923 	}
2924 	ASSERT(be32_to_cpu(entry1->hashval) == be32_to_cpu(entry2->hashval));
2925 	ASSERT(namelen1 == namelen2);
2926 	ASSERT(memcmp(name1, name2, namelen1) == 0);
2927 #endif /* DEBUG */
2928 
2929 	ASSERT(entry1->flags & XFS_ATTR_INCOMPLETE);
2930 	ASSERT((entry2->flags & XFS_ATTR_INCOMPLETE) == 0);
2931 
2932 	entry1->flags &= ~XFS_ATTR_INCOMPLETE;
2933 	xfs_trans_log_buf(args->trans, bp1,
2934 			  XFS_DA_LOGRANGE(leaf1, entry1, sizeof(*entry1)));
2935 	if (args->rmtblkno) {
2936 		ASSERT((entry1->flags & XFS_ATTR_LOCAL) == 0);
2937 		name_rmt = xfs_attr3_leaf_name_remote(leaf1, args->index);
2938 		name_rmt->valueblk = cpu_to_be32(args->rmtblkno);
2939 		name_rmt->valuelen = cpu_to_be32(args->rmtvaluelen);
2940 		xfs_trans_log_buf(args->trans, bp1,
2941 			 XFS_DA_LOGRANGE(leaf1, name_rmt, sizeof(*name_rmt)));
2942 	}
2943 
2944 	entry2->flags |= XFS_ATTR_INCOMPLETE;
2945 	xfs_trans_log_buf(args->trans, bp2,
2946 			  XFS_DA_LOGRANGE(leaf2, entry2, sizeof(*entry2)));
2947 	if ((entry2->flags & XFS_ATTR_LOCAL) == 0) {
2948 		name_rmt = xfs_attr3_leaf_name_remote(leaf2, args->index2);
2949 		name_rmt->valueblk = 0;
2950 		name_rmt->valuelen = 0;
2951 		xfs_trans_log_buf(args->trans, bp2,
2952 			 XFS_DA_LOGRANGE(leaf2, name_rmt, sizeof(*name_rmt)));
2953 	}
2954 
2955 	return 0;
2956 }
2957