xref: /linux/fs/xfs/libxfs/xfs_attr_leaf.c (revision 9a6b55ac)
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 	 * In recovery there is a transient state where count == 0 is valid
313 	 * because we may have transitioned an empty shortform attr to a leaf
314 	 * if the attr didn't fit in shortform.
315 	 */
316 	if (!xfs_log_in_recovery(mp) && ichdr.count == 0)
317 		return __this_address;
318 
319 	/*
320 	 * firstused is the block offset of the first name info structure.
321 	 * Make sure it doesn't go off the block or crash into the header.
322 	 */
323 	if (ichdr.firstused > mp->m_attr_geo->blksize)
324 		return __this_address;
325 	if (ichdr.firstused < xfs_attr3_leaf_hdr_size(leaf))
326 		return __this_address;
327 
328 	/* Make sure the entries array doesn't crash into the name info. */
329 	entries = xfs_attr3_leaf_entryp(bp->b_addr);
330 	if ((char *)&entries[ichdr.count] >
331 	    (char *)bp->b_addr + ichdr.firstused)
332 		return __this_address;
333 
334 	buf_end = (char *)bp->b_addr + mp->m_attr_geo->blksize;
335 	for (i = 0, ent = entries; i < ichdr.count; ent++, i++) {
336 		fa = xfs_attr3_leaf_verify_entry(mp, buf_end, leaf, &ichdr,
337 				ent, i, &last_hashval);
338 		if (fa)
339 			return fa;
340 	}
341 
342 	/*
343 	 * Quickly check the freemap information.  Attribute data has to be
344 	 * aligned to 4-byte boundaries, and likewise for the free space.
345 	 *
346 	 * Note that for 64k block size filesystems, the freemap entries cannot
347 	 * overflow as they are only be16 fields. However, when checking end
348 	 * pointer of the freemap, we have to be careful to detect overflows and
349 	 * so use uint32_t for those checks.
350 	 */
351 	for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
352 		if (ichdr.freemap[i].base > mp->m_attr_geo->blksize)
353 			return __this_address;
354 		if (ichdr.freemap[i].base & 0x3)
355 			return __this_address;
356 		if (ichdr.freemap[i].size > mp->m_attr_geo->blksize)
357 			return __this_address;
358 		if (ichdr.freemap[i].size & 0x3)
359 			return __this_address;
360 
361 		/* be care of 16 bit overflows here */
362 		end = (uint32_t)ichdr.freemap[i].base + ichdr.freemap[i].size;
363 		if (end < ichdr.freemap[i].base)
364 			return __this_address;
365 		if (end > mp->m_attr_geo->blksize)
366 			return __this_address;
367 	}
368 
369 	return NULL;
370 }
371 
372 static void
373 xfs_attr3_leaf_write_verify(
374 	struct xfs_buf	*bp)
375 {
376 	struct xfs_mount	*mp = bp->b_mount;
377 	struct xfs_buf_log_item	*bip = bp->b_log_item;
378 	struct xfs_attr3_leaf_hdr *hdr3 = bp->b_addr;
379 	xfs_failaddr_t		fa;
380 
381 	fa = xfs_attr3_leaf_verify(bp);
382 	if (fa) {
383 		xfs_verifier_error(bp, -EFSCORRUPTED, fa);
384 		return;
385 	}
386 
387 	if (!xfs_sb_version_hascrc(&mp->m_sb))
388 		return;
389 
390 	if (bip)
391 		hdr3->info.lsn = cpu_to_be64(bip->bli_item.li_lsn);
392 
393 	xfs_buf_update_cksum(bp, XFS_ATTR3_LEAF_CRC_OFF);
394 }
395 
396 /*
397  * leaf/node format detection on trees is sketchy, so a node read can be done on
398  * leaf level blocks when detection identifies the tree as a node format tree
399  * incorrectly. In this case, we need to swap the verifier to match the correct
400  * format of the block being read.
401  */
402 static void
403 xfs_attr3_leaf_read_verify(
404 	struct xfs_buf		*bp)
405 {
406 	struct xfs_mount	*mp = bp->b_mount;
407 	xfs_failaddr_t		fa;
408 
409 	if (xfs_sb_version_hascrc(&mp->m_sb) &&
410 	     !xfs_buf_verify_cksum(bp, XFS_ATTR3_LEAF_CRC_OFF))
411 		xfs_verifier_error(bp, -EFSBADCRC, __this_address);
412 	else {
413 		fa = xfs_attr3_leaf_verify(bp);
414 		if (fa)
415 			xfs_verifier_error(bp, -EFSCORRUPTED, fa);
416 	}
417 }
418 
419 const struct xfs_buf_ops xfs_attr3_leaf_buf_ops = {
420 	.name = "xfs_attr3_leaf",
421 	.magic16 = { cpu_to_be16(XFS_ATTR_LEAF_MAGIC),
422 		     cpu_to_be16(XFS_ATTR3_LEAF_MAGIC) },
423 	.verify_read = xfs_attr3_leaf_read_verify,
424 	.verify_write = xfs_attr3_leaf_write_verify,
425 	.verify_struct = xfs_attr3_leaf_verify,
426 };
427 
428 int
429 xfs_attr3_leaf_read(
430 	struct xfs_trans	*tp,
431 	struct xfs_inode	*dp,
432 	xfs_dablk_t		bno,
433 	struct xfs_buf		**bpp)
434 {
435 	int			err;
436 
437 	err = xfs_da_read_buf(tp, dp, bno, 0, bpp, XFS_ATTR_FORK,
438 			&xfs_attr3_leaf_buf_ops);
439 	if (!err && tp && *bpp)
440 		xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_ATTR_LEAF_BUF);
441 	return err;
442 }
443 
444 /*========================================================================
445  * Namespace helper routines
446  *========================================================================*/
447 
448 /*
449  * If namespace bits don't match return 0.
450  * If all match then return 1.
451  */
452 STATIC int
453 xfs_attr_namesp_match(int arg_flags, int ondisk_flags)
454 {
455 	return XFS_ATTR_NSP_ONDISK(ondisk_flags) == XFS_ATTR_NSP_ARGS_TO_ONDISK(arg_flags);
456 }
457 
458 static int
459 xfs_attr_copy_value(
460 	struct xfs_da_args	*args,
461 	unsigned char		*value,
462 	int			valuelen)
463 {
464 	/*
465 	 * No copy if all we have to do is get the length
466 	 */
467 	if (args->flags & ATTR_KERNOVAL) {
468 		args->valuelen = valuelen;
469 		return 0;
470 	}
471 
472 	/*
473 	 * No copy if the length of the existing buffer is too small
474 	 */
475 	if (args->valuelen < valuelen) {
476 		args->valuelen = valuelen;
477 		return -ERANGE;
478 	}
479 
480 	if (args->op_flags & XFS_DA_OP_ALLOCVAL) {
481 		args->value = kmem_alloc_large(valuelen, 0);
482 		if (!args->value)
483 			return -ENOMEM;
484 	}
485 	args->valuelen = valuelen;
486 
487 	/* remote block xattr requires IO for copy-in */
488 	if (args->rmtblkno)
489 		return xfs_attr_rmtval_get(args);
490 
491 	/*
492 	 * This is to prevent a GCC warning because the remote xattr case
493 	 * doesn't have a value to pass in. In that case, we never reach here,
494 	 * but GCC can't work that out and so throws a "passing NULL to
495 	 * memcpy" warning.
496 	 */
497 	if (!value)
498 		return -EINVAL;
499 	memcpy(args->value, value, valuelen);
500 	return 0;
501 }
502 
503 /*========================================================================
504  * External routines when attribute fork size < XFS_LITINO(mp).
505  *========================================================================*/
506 
507 /*
508  * Query whether the requested number of additional bytes of extended
509  * attribute space will be able to fit inline.
510  *
511  * Returns zero if not, else the di_forkoff fork offset to be used in the
512  * literal area for attribute data once the new bytes have been added.
513  *
514  * di_forkoff must be 8 byte aligned, hence is stored as a >>3 value;
515  * special case for dev/uuid inodes, they have fixed size data forks.
516  */
517 int
518 xfs_attr_shortform_bytesfit(
519 	struct xfs_inode	*dp,
520 	int			bytes)
521 {
522 	struct xfs_mount	*mp = dp->i_mount;
523 	int64_t			dsize;
524 	int			minforkoff;
525 	int			maxforkoff;
526 	int			offset;
527 
528 	/* rounded down */
529 	offset = (XFS_LITINO(mp, dp->i_d.di_version) - bytes) >> 3;
530 
531 	if (dp->i_d.di_format == XFS_DINODE_FMT_DEV) {
532 		minforkoff = roundup(sizeof(xfs_dev_t), 8) >> 3;
533 		return (offset >= minforkoff) ? minforkoff : 0;
534 	}
535 
536 	/*
537 	 * If the requested numbers of bytes is smaller or equal to the
538 	 * current attribute fork size we can always proceed.
539 	 *
540 	 * Note that if_bytes in the data fork might actually be larger than
541 	 * the current data fork size is due to delalloc extents. In that
542 	 * case either the extent count will go down when they are converted
543 	 * to real extents, or the delalloc conversion will take care of the
544 	 * literal area rebalancing.
545 	 */
546 	if (bytes <= XFS_IFORK_ASIZE(dp))
547 		return dp->i_d.di_forkoff;
548 
549 	/*
550 	 * For attr2 we can try to move the forkoff if there is space in the
551 	 * literal area, but for the old format we are done if there is no
552 	 * space in the fixed attribute fork.
553 	 */
554 	if (!(mp->m_flags & XFS_MOUNT_ATTR2))
555 		return 0;
556 
557 	dsize = dp->i_df.if_bytes;
558 
559 	switch (dp->i_d.di_format) {
560 	case XFS_DINODE_FMT_EXTENTS:
561 		/*
562 		 * If there is no attr fork and the data fork is extents,
563 		 * determine if creating the default attr fork will result
564 		 * in the extents form migrating to btree. If so, the
565 		 * minimum offset only needs to be the space required for
566 		 * the btree root.
567 		 */
568 		if (!dp->i_d.di_forkoff && dp->i_df.if_bytes >
569 		    xfs_default_attroffset(dp))
570 			dsize = XFS_BMDR_SPACE_CALC(MINDBTPTRS);
571 		break;
572 	case XFS_DINODE_FMT_BTREE:
573 		/*
574 		 * If we have a data btree then keep forkoff if we have one,
575 		 * otherwise we are adding a new attr, so then we set
576 		 * minforkoff to where the btree root can finish so we have
577 		 * plenty of room for attrs
578 		 */
579 		if (dp->i_d.di_forkoff) {
580 			if (offset < dp->i_d.di_forkoff)
581 				return 0;
582 			return dp->i_d.di_forkoff;
583 		}
584 		dsize = XFS_BMAP_BROOT_SPACE(mp, dp->i_df.if_broot);
585 		break;
586 	}
587 
588 	/*
589 	 * A data fork btree root must have space for at least
590 	 * MINDBTPTRS key/ptr pairs if the data fork is small or empty.
591 	 */
592 	minforkoff = max_t(int64_t, dsize, XFS_BMDR_SPACE_CALC(MINDBTPTRS));
593 	minforkoff = roundup(minforkoff, 8) >> 3;
594 
595 	/* attr fork btree root can have at least this many key/ptr pairs */
596 	maxforkoff = XFS_LITINO(mp, dp->i_d.di_version) -
597 			XFS_BMDR_SPACE_CALC(MINABTPTRS);
598 	maxforkoff = maxforkoff >> 3;	/* rounded down */
599 
600 	if (offset >= maxforkoff)
601 		return maxforkoff;
602 	if (offset >= minforkoff)
603 		return offset;
604 	return 0;
605 }
606 
607 /*
608  * Switch on the ATTR2 superblock bit (implies also FEATURES2)
609  */
610 STATIC void
611 xfs_sbversion_add_attr2(xfs_mount_t *mp, xfs_trans_t *tp)
612 {
613 	if ((mp->m_flags & XFS_MOUNT_ATTR2) &&
614 	    !(xfs_sb_version_hasattr2(&mp->m_sb))) {
615 		spin_lock(&mp->m_sb_lock);
616 		if (!xfs_sb_version_hasattr2(&mp->m_sb)) {
617 			xfs_sb_version_addattr2(&mp->m_sb);
618 			spin_unlock(&mp->m_sb_lock);
619 			xfs_log_sb(tp);
620 		} else
621 			spin_unlock(&mp->m_sb_lock);
622 	}
623 }
624 
625 /*
626  * Create the initial contents of a shortform attribute list.
627  */
628 void
629 xfs_attr_shortform_create(xfs_da_args_t *args)
630 {
631 	xfs_attr_sf_hdr_t *hdr;
632 	xfs_inode_t *dp;
633 	struct xfs_ifork *ifp;
634 
635 	trace_xfs_attr_sf_create(args);
636 
637 	dp = args->dp;
638 	ASSERT(dp != NULL);
639 	ifp = dp->i_afp;
640 	ASSERT(ifp != NULL);
641 	ASSERT(ifp->if_bytes == 0);
642 	if (dp->i_d.di_aformat == XFS_DINODE_FMT_EXTENTS) {
643 		ifp->if_flags &= ~XFS_IFEXTENTS;	/* just in case */
644 		dp->i_d.di_aformat = XFS_DINODE_FMT_LOCAL;
645 		ifp->if_flags |= XFS_IFINLINE;
646 	} else {
647 		ASSERT(ifp->if_flags & XFS_IFINLINE);
648 	}
649 	xfs_idata_realloc(dp, sizeof(*hdr), XFS_ATTR_FORK);
650 	hdr = (xfs_attr_sf_hdr_t *)ifp->if_u1.if_data;
651 	hdr->count = 0;
652 	hdr->totsize = cpu_to_be16(sizeof(*hdr));
653 	xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE | XFS_ILOG_ADATA);
654 }
655 
656 /*
657  * Add a name/value pair to the shortform attribute list.
658  * Overflow from the inode has already been checked for.
659  */
660 void
661 xfs_attr_shortform_add(xfs_da_args_t *args, int forkoff)
662 {
663 	xfs_attr_shortform_t *sf;
664 	xfs_attr_sf_entry_t *sfe;
665 	int i, offset, size;
666 	xfs_mount_t *mp;
667 	xfs_inode_t *dp;
668 	struct xfs_ifork *ifp;
669 
670 	trace_xfs_attr_sf_add(args);
671 
672 	dp = args->dp;
673 	mp = dp->i_mount;
674 	dp->i_d.di_forkoff = forkoff;
675 
676 	ifp = dp->i_afp;
677 	ASSERT(ifp->if_flags & XFS_IFINLINE);
678 	sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
679 	sfe = &sf->list[0];
680 	for (i = 0; i < sf->hdr.count; sfe = XFS_ATTR_SF_NEXTENTRY(sfe), i++) {
681 #ifdef DEBUG
682 		if (sfe->namelen != args->namelen)
683 			continue;
684 		if (memcmp(args->name, sfe->nameval, args->namelen) != 0)
685 			continue;
686 		if (!xfs_attr_namesp_match(args->flags, sfe->flags))
687 			continue;
688 		ASSERT(0);
689 #endif
690 	}
691 
692 	offset = (char *)sfe - (char *)sf;
693 	size = XFS_ATTR_SF_ENTSIZE_BYNAME(args->namelen, args->valuelen);
694 	xfs_idata_realloc(dp, size, XFS_ATTR_FORK);
695 	sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
696 	sfe = (xfs_attr_sf_entry_t *)((char *)sf + offset);
697 
698 	sfe->namelen = args->namelen;
699 	sfe->valuelen = args->valuelen;
700 	sfe->flags = XFS_ATTR_NSP_ARGS_TO_ONDISK(args->flags);
701 	memcpy(sfe->nameval, args->name, args->namelen);
702 	memcpy(&sfe->nameval[args->namelen], args->value, args->valuelen);
703 	sf->hdr.count++;
704 	be16_add_cpu(&sf->hdr.totsize, size);
705 	xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE | XFS_ILOG_ADATA);
706 
707 	xfs_sbversion_add_attr2(mp, args->trans);
708 }
709 
710 /*
711  * After the last attribute is removed revert to original inode format,
712  * making all literal area available to the data fork once more.
713  */
714 void
715 xfs_attr_fork_remove(
716 	struct xfs_inode	*ip,
717 	struct xfs_trans	*tp)
718 {
719 	xfs_idestroy_fork(ip, XFS_ATTR_FORK);
720 	ip->i_d.di_forkoff = 0;
721 	ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
722 
723 	ASSERT(ip->i_d.di_anextents == 0);
724 	ASSERT(ip->i_afp == NULL);
725 
726 	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
727 }
728 
729 /*
730  * Remove an attribute from the shortform attribute list structure.
731  */
732 int
733 xfs_attr_shortform_remove(xfs_da_args_t *args)
734 {
735 	xfs_attr_shortform_t *sf;
736 	xfs_attr_sf_entry_t *sfe;
737 	int base, size=0, end, totsize, i;
738 	xfs_mount_t *mp;
739 	xfs_inode_t *dp;
740 
741 	trace_xfs_attr_sf_remove(args);
742 
743 	dp = args->dp;
744 	mp = dp->i_mount;
745 	base = sizeof(xfs_attr_sf_hdr_t);
746 	sf = (xfs_attr_shortform_t *)dp->i_afp->if_u1.if_data;
747 	sfe = &sf->list[0];
748 	end = sf->hdr.count;
749 	for (i = 0; i < end; sfe = XFS_ATTR_SF_NEXTENTRY(sfe),
750 					base += size, i++) {
751 		size = XFS_ATTR_SF_ENTSIZE(sfe);
752 		if (sfe->namelen != args->namelen)
753 			continue;
754 		if (memcmp(sfe->nameval, args->name, args->namelen) != 0)
755 			continue;
756 		if (!xfs_attr_namesp_match(args->flags, sfe->flags))
757 			continue;
758 		break;
759 	}
760 	if (i == end)
761 		return -ENOATTR;
762 
763 	/*
764 	 * Fix up the attribute fork data, covering the hole
765 	 */
766 	end = base + size;
767 	totsize = be16_to_cpu(sf->hdr.totsize);
768 	if (end != totsize)
769 		memmove(&((char *)sf)[base], &((char *)sf)[end], totsize - end);
770 	sf->hdr.count--;
771 	be16_add_cpu(&sf->hdr.totsize, -size);
772 
773 	/*
774 	 * Fix up the start offset of the attribute fork
775 	 */
776 	totsize -= size;
777 	if (totsize == sizeof(xfs_attr_sf_hdr_t) &&
778 	    (mp->m_flags & XFS_MOUNT_ATTR2) &&
779 	    (dp->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
780 	    !(args->op_flags & XFS_DA_OP_ADDNAME)) {
781 		xfs_attr_fork_remove(dp, args->trans);
782 	} else {
783 		xfs_idata_realloc(dp, -size, XFS_ATTR_FORK);
784 		dp->i_d.di_forkoff = xfs_attr_shortform_bytesfit(dp, totsize);
785 		ASSERT(dp->i_d.di_forkoff);
786 		ASSERT(totsize > sizeof(xfs_attr_sf_hdr_t) ||
787 				(args->op_flags & XFS_DA_OP_ADDNAME) ||
788 				!(mp->m_flags & XFS_MOUNT_ATTR2) ||
789 				dp->i_d.di_format == XFS_DINODE_FMT_BTREE);
790 		xfs_trans_log_inode(args->trans, dp,
791 					XFS_ILOG_CORE | XFS_ILOG_ADATA);
792 	}
793 
794 	xfs_sbversion_add_attr2(mp, args->trans);
795 
796 	return 0;
797 }
798 
799 /*
800  * Look up a name in a shortform attribute list structure.
801  */
802 /*ARGSUSED*/
803 int
804 xfs_attr_shortform_lookup(xfs_da_args_t *args)
805 {
806 	xfs_attr_shortform_t *sf;
807 	xfs_attr_sf_entry_t *sfe;
808 	int i;
809 	struct xfs_ifork *ifp;
810 
811 	trace_xfs_attr_sf_lookup(args);
812 
813 	ifp = args->dp->i_afp;
814 	ASSERT(ifp->if_flags & XFS_IFINLINE);
815 	sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
816 	sfe = &sf->list[0];
817 	for (i = 0; i < sf->hdr.count;
818 				sfe = XFS_ATTR_SF_NEXTENTRY(sfe), i++) {
819 		if (sfe->namelen != args->namelen)
820 			continue;
821 		if (memcmp(args->name, sfe->nameval, args->namelen) != 0)
822 			continue;
823 		if (!xfs_attr_namesp_match(args->flags, sfe->flags))
824 			continue;
825 		return -EEXIST;
826 	}
827 	return -ENOATTR;
828 }
829 
830 /*
831  * Retrieve the attribute value and length.
832  *
833  * If ATTR_KERNOVAL is specified, only the length needs to be returned.
834  * Unlike a lookup, we only return an error if the attribute does not
835  * exist or we can't retrieve the value.
836  */
837 int
838 xfs_attr_shortform_getvalue(
839 	struct xfs_da_args	*args)
840 {
841 	struct xfs_attr_shortform *sf;
842 	struct xfs_attr_sf_entry *sfe;
843 	int			i;
844 
845 	ASSERT(args->dp->i_afp->if_flags == XFS_IFINLINE);
846 	sf = (xfs_attr_shortform_t *)args->dp->i_afp->if_u1.if_data;
847 	sfe = &sf->list[0];
848 	for (i = 0; i < sf->hdr.count;
849 				sfe = XFS_ATTR_SF_NEXTENTRY(sfe), i++) {
850 		if (sfe->namelen != args->namelen)
851 			continue;
852 		if (memcmp(args->name, sfe->nameval, args->namelen) != 0)
853 			continue;
854 		if (!xfs_attr_namesp_match(args->flags, sfe->flags))
855 			continue;
856 		return xfs_attr_copy_value(args, &sfe->nameval[args->namelen],
857 						sfe->valuelen);
858 	}
859 	return -ENOATTR;
860 }
861 
862 /*
863  * Convert from using the shortform to the leaf.  On success, return the
864  * buffer so that we can keep it locked until we're totally done with it.
865  */
866 int
867 xfs_attr_shortform_to_leaf(
868 	struct xfs_da_args		*args,
869 	struct xfs_buf			**leaf_bp)
870 {
871 	struct xfs_inode		*dp;
872 	struct xfs_attr_shortform	*sf;
873 	struct xfs_attr_sf_entry	*sfe;
874 	struct xfs_da_args		nargs;
875 	char				*tmpbuffer;
876 	int				error, i, size;
877 	xfs_dablk_t			blkno;
878 	struct xfs_buf			*bp;
879 	struct xfs_ifork		*ifp;
880 
881 	trace_xfs_attr_sf_to_leaf(args);
882 
883 	dp = args->dp;
884 	ifp = dp->i_afp;
885 	sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
886 	size = be16_to_cpu(sf->hdr.totsize);
887 	tmpbuffer = kmem_alloc(size, 0);
888 	ASSERT(tmpbuffer != NULL);
889 	memcpy(tmpbuffer, ifp->if_u1.if_data, size);
890 	sf = (xfs_attr_shortform_t *)tmpbuffer;
891 
892 	xfs_idata_realloc(dp, -size, XFS_ATTR_FORK);
893 	xfs_bmap_local_to_extents_empty(args->trans, dp, XFS_ATTR_FORK);
894 
895 	bp = NULL;
896 	error = xfs_da_grow_inode(args, &blkno);
897 	if (error)
898 		goto out;
899 
900 	ASSERT(blkno == 0);
901 	error = xfs_attr3_leaf_create(args, blkno, &bp);
902 	if (error)
903 		goto out;
904 
905 	memset((char *)&nargs, 0, sizeof(nargs));
906 	nargs.dp = dp;
907 	nargs.geo = args->geo;
908 	nargs.total = args->total;
909 	nargs.whichfork = XFS_ATTR_FORK;
910 	nargs.trans = args->trans;
911 	nargs.op_flags = XFS_DA_OP_OKNOENT;
912 
913 	sfe = &sf->list[0];
914 	for (i = 0; i < sf->hdr.count; i++) {
915 		nargs.name = sfe->nameval;
916 		nargs.namelen = sfe->namelen;
917 		nargs.value = &sfe->nameval[nargs.namelen];
918 		nargs.valuelen = sfe->valuelen;
919 		nargs.hashval = xfs_da_hashname(sfe->nameval,
920 						sfe->namelen);
921 		nargs.flags = XFS_ATTR_NSP_ONDISK_TO_ARGS(sfe->flags);
922 		error = xfs_attr3_leaf_lookup_int(bp, &nargs); /* set a->index */
923 		ASSERT(error == -ENOATTR);
924 		error = xfs_attr3_leaf_add(bp, &nargs);
925 		ASSERT(error != -ENOSPC);
926 		if (error)
927 			goto out;
928 		sfe = XFS_ATTR_SF_NEXTENTRY(sfe);
929 	}
930 	error = 0;
931 	*leaf_bp = bp;
932 out:
933 	kmem_free(tmpbuffer);
934 	return error;
935 }
936 
937 /*
938  * Check a leaf attribute block to see if all the entries would fit into
939  * a shortform attribute list.
940  */
941 int
942 xfs_attr_shortform_allfit(
943 	struct xfs_buf		*bp,
944 	struct xfs_inode	*dp)
945 {
946 	struct xfs_attr_leafblock *leaf;
947 	struct xfs_attr_leaf_entry *entry;
948 	xfs_attr_leaf_name_local_t *name_loc;
949 	struct xfs_attr3_icleaf_hdr leafhdr;
950 	int			bytes;
951 	int			i;
952 	struct xfs_mount	*mp = bp->b_mount;
953 
954 	leaf = bp->b_addr;
955 	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &leafhdr, leaf);
956 	entry = xfs_attr3_leaf_entryp(leaf);
957 
958 	bytes = sizeof(struct xfs_attr_sf_hdr);
959 	for (i = 0; i < leafhdr.count; entry++, i++) {
960 		if (entry->flags & XFS_ATTR_INCOMPLETE)
961 			continue;		/* don't copy partial entries */
962 		if (!(entry->flags & XFS_ATTR_LOCAL))
963 			return 0;
964 		name_loc = xfs_attr3_leaf_name_local(leaf, i);
965 		if (name_loc->namelen >= XFS_ATTR_SF_ENTSIZE_MAX)
966 			return 0;
967 		if (be16_to_cpu(name_loc->valuelen) >= XFS_ATTR_SF_ENTSIZE_MAX)
968 			return 0;
969 		bytes += sizeof(struct xfs_attr_sf_entry) - 1
970 				+ name_loc->namelen
971 				+ be16_to_cpu(name_loc->valuelen);
972 	}
973 	if ((dp->i_mount->m_flags & XFS_MOUNT_ATTR2) &&
974 	    (dp->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
975 	    (bytes == sizeof(struct xfs_attr_sf_hdr)))
976 		return -1;
977 	return xfs_attr_shortform_bytesfit(dp, bytes);
978 }
979 
980 /* Verify the consistency of an inline attribute fork. */
981 xfs_failaddr_t
982 xfs_attr_shortform_verify(
983 	struct xfs_inode		*ip)
984 {
985 	struct xfs_attr_shortform	*sfp;
986 	struct xfs_attr_sf_entry	*sfep;
987 	struct xfs_attr_sf_entry	*next_sfep;
988 	char				*endp;
989 	struct xfs_ifork		*ifp;
990 	int				i;
991 	int64_t				size;
992 
993 	ASSERT(ip->i_d.di_aformat == XFS_DINODE_FMT_LOCAL);
994 	ifp = XFS_IFORK_PTR(ip, XFS_ATTR_FORK);
995 	sfp = (struct xfs_attr_shortform *)ifp->if_u1.if_data;
996 	size = ifp->if_bytes;
997 
998 	/*
999 	 * Give up if the attribute is way too short.
1000 	 */
1001 	if (size < sizeof(struct xfs_attr_sf_hdr))
1002 		return __this_address;
1003 
1004 	endp = (char *)sfp + size;
1005 
1006 	/* Check all reported entries */
1007 	sfep = &sfp->list[0];
1008 	for (i = 0; i < sfp->hdr.count; i++) {
1009 		/*
1010 		 * struct xfs_attr_sf_entry has a variable length.
1011 		 * Check the fixed-offset parts of the structure are
1012 		 * within the data buffer.
1013 		 */
1014 		if (((char *)sfep + sizeof(*sfep)) >= endp)
1015 			return __this_address;
1016 
1017 		/* Don't allow names with known bad length. */
1018 		if (sfep->namelen == 0)
1019 			return __this_address;
1020 
1021 		/*
1022 		 * Check that the variable-length part of the structure is
1023 		 * within the data buffer.  The next entry starts after the
1024 		 * name component, so nextentry is an acceptable test.
1025 		 */
1026 		next_sfep = XFS_ATTR_SF_NEXTENTRY(sfep);
1027 		if ((char *)next_sfep > endp)
1028 			return __this_address;
1029 
1030 		/*
1031 		 * Check for unknown flags.  Short form doesn't support
1032 		 * the incomplete or local bits, so we can use the namespace
1033 		 * mask here.
1034 		 */
1035 		if (sfep->flags & ~XFS_ATTR_NSP_ONDISK_MASK)
1036 			return __this_address;
1037 
1038 		/*
1039 		 * Check for invalid namespace combinations.  We only allow
1040 		 * one namespace flag per xattr, so we can just count the
1041 		 * bits (i.e. hweight) here.
1042 		 */
1043 		if (hweight8(sfep->flags & XFS_ATTR_NSP_ONDISK_MASK) > 1)
1044 			return __this_address;
1045 
1046 		sfep = next_sfep;
1047 	}
1048 	if ((void *)sfep != (void *)endp)
1049 		return __this_address;
1050 
1051 	return NULL;
1052 }
1053 
1054 /*
1055  * Convert a leaf attribute list to shortform attribute list
1056  */
1057 int
1058 xfs_attr3_leaf_to_shortform(
1059 	struct xfs_buf		*bp,
1060 	struct xfs_da_args	*args,
1061 	int			forkoff)
1062 {
1063 	struct xfs_attr_leafblock *leaf;
1064 	struct xfs_attr3_icleaf_hdr ichdr;
1065 	struct xfs_attr_leaf_entry *entry;
1066 	struct xfs_attr_leaf_name_local *name_loc;
1067 	struct xfs_da_args	nargs;
1068 	struct xfs_inode	*dp = args->dp;
1069 	char			*tmpbuffer;
1070 	int			error;
1071 	int			i;
1072 
1073 	trace_xfs_attr_leaf_to_sf(args);
1074 
1075 	tmpbuffer = kmem_alloc(args->geo->blksize, 0);
1076 	if (!tmpbuffer)
1077 		return -ENOMEM;
1078 
1079 	memcpy(tmpbuffer, bp->b_addr, args->geo->blksize);
1080 
1081 	leaf = (xfs_attr_leafblock_t *)tmpbuffer;
1082 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
1083 	entry = xfs_attr3_leaf_entryp(leaf);
1084 
1085 	/* XXX (dgc): buffer is about to be marked stale - why zero it? */
1086 	memset(bp->b_addr, 0, args->geo->blksize);
1087 
1088 	/*
1089 	 * Clean out the prior contents of the attribute list.
1090 	 */
1091 	error = xfs_da_shrink_inode(args, 0, bp);
1092 	if (error)
1093 		goto out;
1094 
1095 	if (forkoff == -1) {
1096 		ASSERT(dp->i_mount->m_flags & XFS_MOUNT_ATTR2);
1097 		ASSERT(dp->i_d.di_format != XFS_DINODE_FMT_BTREE);
1098 		xfs_attr_fork_remove(dp, args->trans);
1099 		goto out;
1100 	}
1101 
1102 	xfs_attr_shortform_create(args);
1103 
1104 	/*
1105 	 * Copy the attributes
1106 	 */
1107 	memset((char *)&nargs, 0, sizeof(nargs));
1108 	nargs.geo = args->geo;
1109 	nargs.dp = dp;
1110 	nargs.total = args->total;
1111 	nargs.whichfork = XFS_ATTR_FORK;
1112 	nargs.trans = args->trans;
1113 	nargs.op_flags = XFS_DA_OP_OKNOENT;
1114 
1115 	for (i = 0; i < ichdr.count; entry++, i++) {
1116 		if (entry->flags & XFS_ATTR_INCOMPLETE)
1117 			continue;	/* don't copy partial entries */
1118 		if (!entry->nameidx)
1119 			continue;
1120 		ASSERT(entry->flags & XFS_ATTR_LOCAL);
1121 		name_loc = xfs_attr3_leaf_name_local(leaf, i);
1122 		nargs.name = name_loc->nameval;
1123 		nargs.namelen = name_loc->namelen;
1124 		nargs.value = &name_loc->nameval[nargs.namelen];
1125 		nargs.valuelen = be16_to_cpu(name_loc->valuelen);
1126 		nargs.hashval = be32_to_cpu(entry->hashval);
1127 		nargs.flags = XFS_ATTR_NSP_ONDISK_TO_ARGS(entry->flags);
1128 		xfs_attr_shortform_add(&nargs, forkoff);
1129 	}
1130 	error = 0;
1131 
1132 out:
1133 	kmem_free(tmpbuffer);
1134 	return error;
1135 }
1136 
1137 /*
1138  * Convert from using a single leaf to a root node and a leaf.
1139  */
1140 int
1141 xfs_attr3_leaf_to_node(
1142 	struct xfs_da_args	*args)
1143 {
1144 	struct xfs_attr_leafblock *leaf;
1145 	struct xfs_attr3_icleaf_hdr icleafhdr;
1146 	struct xfs_attr_leaf_entry *entries;
1147 	struct xfs_da3_icnode_hdr icnodehdr;
1148 	struct xfs_da_intnode	*node;
1149 	struct xfs_inode	*dp = args->dp;
1150 	struct xfs_mount	*mp = dp->i_mount;
1151 	struct xfs_buf		*bp1 = NULL;
1152 	struct xfs_buf		*bp2 = NULL;
1153 	xfs_dablk_t		blkno;
1154 	int			error;
1155 
1156 	trace_xfs_attr_leaf_to_node(args);
1157 
1158 	error = xfs_da_grow_inode(args, &blkno);
1159 	if (error)
1160 		goto out;
1161 	error = xfs_attr3_leaf_read(args->trans, dp, 0, &bp1);
1162 	if (error)
1163 		goto out;
1164 
1165 	error = xfs_da_get_buf(args->trans, dp, blkno, &bp2, XFS_ATTR_FORK);
1166 	if (error)
1167 		goto out;
1168 
1169 	/* copy leaf to new buffer, update identifiers */
1170 	xfs_trans_buf_set_type(args->trans, bp2, XFS_BLFT_ATTR_LEAF_BUF);
1171 	bp2->b_ops = bp1->b_ops;
1172 	memcpy(bp2->b_addr, bp1->b_addr, args->geo->blksize);
1173 	if (xfs_sb_version_hascrc(&mp->m_sb)) {
1174 		struct xfs_da3_blkinfo *hdr3 = bp2->b_addr;
1175 		hdr3->blkno = cpu_to_be64(bp2->b_bn);
1176 	}
1177 	xfs_trans_log_buf(args->trans, bp2, 0, args->geo->blksize - 1);
1178 
1179 	/*
1180 	 * Set up the new root node.
1181 	 */
1182 	error = xfs_da3_node_create(args, 0, 1, &bp1, XFS_ATTR_FORK);
1183 	if (error)
1184 		goto out;
1185 	node = bp1->b_addr;
1186 	xfs_da3_node_hdr_from_disk(mp, &icnodehdr, node);
1187 
1188 	leaf = bp2->b_addr;
1189 	xfs_attr3_leaf_hdr_from_disk(args->geo, &icleafhdr, leaf);
1190 	entries = xfs_attr3_leaf_entryp(leaf);
1191 
1192 	/* both on-disk, don't endian-flip twice */
1193 	icnodehdr.btree[0].hashval = entries[icleafhdr.count - 1].hashval;
1194 	icnodehdr.btree[0].before = cpu_to_be32(blkno);
1195 	icnodehdr.count = 1;
1196 	xfs_da3_node_hdr_to_disk(dp->i_mount, node, &icnodehdr);
1197 	xfs_trans_log_buf(args->trans, bp1, 0, args->geo->blksize - 1);
1198 	error = 0;
1199 out:
1200 	return error;
1201 }
1202 
1203 /*========================================================================
1204  * Routines used for growing the Btree.
1205  *========================================================================*/
1206 
1207 /*
1208  * Create the initial contents of a leaf attribute list
1209  * or a leaf in a node attribute list.
1210  */
1211 STATIC int
1212 xfs_attr3_leaf_create(
1213 	struct xfs_da_args	*args,
1214 	xfs_dablk_t		blkno,
1215 	struct xfs_buf		**bpp)
1216 {
1217 	struct xfs_attr_leafblock *leaf;
1218 	struct xfs_attr3_icleaf_hdr ichdr;
1219 	struct xfs_inode	*dp = args->dp;
1220 	struct xfs_mount	*mp = dp->i_mount;
1221 	struct xfs_buf		*bp;
1222 	int			error;
1223 
1224 	trace_xfs_attr_leaf_create(args);
1225 
1226 	error = xfs_da_get_buf(args->trans, args->dp, blkno, &bp,
1227 					    XFS_ATTR_FORK);
1228 	if (error)
1229 		return error;
1230 	bp->b_ops = &xfs_attr3_leaf_buf_ops;
1231 	xfs_trans_buf_set_type(args->trans, bp, XFS_BLFT_ATTR_LEAF_BUF);
1232 	leaf = bp->b_addr;
1233 	memset(leaf, 0, args->geo->blksize);
1234 
1235 	memset(&ichdr, 0, sizeof(ichdr));
1236 	ichdr.firstused = args->geo->blksize;
1237 
1238 	if (xfs_sb_version_hascrc(&mp->m_sb)) {
1239 		struct xfs_da3_blkinfo *hdr3 = bp->b_addr;
1240 
1241 		ichdr.magic = XFS_ATTR3_LEAF_MAGIC;
1242 
1243 		hdr3->blkno = cpu_to_be64(bp->b_bn);
1244 		hdr3->owner = cpu_to_be64(dp->i_ino);
1245 		uuid_copy(&hdr3->uuid, &mp->m_sb.sb_meta_uuid);
1246 
1247 		ichdr.freemap[0].base = sizeof(struct xfs_attr3_leaf_hdr);
1248 	} else {
1249 		ichdr.magic = XFS_ATTR_LEAF_MAGIC;
1250 		ichdr.freemap[0].base = sizeof(struct xfs_attr_leaf_hdr);
1251 	}
1252 	ichdr.freemap[0].size = ichdr.firstused - ichdr.freemap[0].base;
1253 
1254 	xfs_attr3_leaf_hdr_to_disk(args->geo, leaf, &ichdr);
1255 	xfs_trans_log_buf(args->trans, bp, 0, args->geo->blksize - 1);
1256 
1257 	*bpp = bp;
1258 	return 0;
1259 }
1260 
1261 /*
1262  * Split the leaf node, rebalance, then add the new entry.
1263  */
1264 int
1265 xfs_attr3_leaf_split(
1266 	struct xfs_da_state	*state,
1267 	struct xfs_da_state_blk	*oldblk,
1268 	struct xfs_da_state_blk	*newblk)
1269 {
1270 	xfs_dablk_t blkno;
1271 	int error;
1272 
1273 	trace_xfs_attr_leaf_split(state->args);
1274 
1275 	/*
1276 	 * Allocate space for a new leaf node.
1277 	 */
1278 	ASSERT(oldblk->magic == XFS_ATTR_LEAF_MAGIC);
1279 	error = xfs_da_grow_inode(state->args, &blkno);
1280 	if (error)
1281 		return error;
1282 	error = xfs_attr3_leaf_create(state->args, blkno, &newblk->bp);
1283 	if (error)
1284 		return error;
1285 	newblk->blkno = blkno;
1286 	newblk->magic = XFS_ATTR_LEAF_MAGIC;
1287 
1288 	/*
1289 	 * Rebalance the entries across the two leaves.
1290 	 * NOTE: rebalance() currently depends on the 2nd block being empty.
1291 	 */
1292 	xfs_attr3_leaf_rebalance(state, oldblk, newblk);
1293 	error = xfs_da3_blk_link(state, oldblk, newblk);
1294 	if (error)
1295 		return error;
1296 
1297 	/*
1298 	 * Save info on "old" attribute for "atomic rename" ops, leaf_add()
1299 	 * modifies the index/blkno/rmtblk/rmtblkcnt fields to show the
1300 	 * "new" attrs info.  Will need the "old" info to remove it later.
1301 	 *
1302 	 * Insert the "new" entry in the correct block.
1303 	 */
1304 	if (state->inleaf) {
1305 		trace_xfs_attr_leaf_add_old(state->args);
1306 		error = xfs_attr3_leaf_add(oldblk->bp, state->args);
1307 	} else {
1308 		trace_xfs_attr_leaf_add_new(state->args);
1309 		error = xfs_attr3_leaf_add(newblk->bp, state->args);
1310 	}
1311 
1312 	/*
1313 	 * Update last hashval in each block since we added the name.
1314 	 */
1315 	oldblk->hashval = xfs_attr_leaf_lasthash(oldblk->bp, NULL);
1316 	newblk->hashval = xfs_attr_leaf_lasthash(newblk->bp, NULL);
1317 	return error;
1318 }
1319 
1320 /*
1321  * Add a name to the leaf attribute list structure.
1322  */
1323 int
1324 xfs_attr3_leaf_add(
1325 	struct xfs_buf		*bp,
1326 	struct xfs_da_args	*args)
1327 {
1328 	struct xfs_attr_leafblock *leaf;
1329 	struct xfs_attr3_icleaf_hdr ichdr;
1330 	int			tablesize;
1331 	int			entsize;
1332 	int			sum;
1333 	int			tmp;
1334 	int			i;
1335 
1336 	trace_xfs_attr_leaf_add(args);
1337 
1338 	leaf = bp->b_addr;
1339 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
1340 	ASSERT(args->index >= 0 && args->index <= ichdr.count);
1341 	entsize = xfs_attr_leaf_newentsize(args, NULL);
1342 
1343 	/*
1344 	 * Search through freemap for first-fit on new name length.
1345 	 * (may need to figure in size of entry struct too)
1346 	 */
1347 	tablesize = (ichdr.count + 1) * sizeof(xfs_attr_leaf_entry_t)
1348 					+ xfs_attr3_leaf_hdr_size(leaf);
1349 	for (sum = 0, i = XFS_ATTR_LEAF_MAPSIZE - 1; i >= 0; i--) {
1350 		if (tablesize > ichdr.firstused) {
1351 			sum += ichdr.freemap[i].size;
1352 			continue;
1353 		}
1354 		if (!ichdr.freemap[i].size)
1355 			continue;	/* no space in this map */
1356 		tmp = entsize;
1357 		if (ichdr.freemap[i].base < ichdr.firstused)
1358 			tmp += sizeof(xfs_attr_leaf_entry_t);
1359 		if (ichdr.freemap[i].size >= tmp) {
1360 			tmp = xfs_attr3_leaf_add_work(bp, &ichdr, args, i);
1361 			goto out_log_hdr;
1362 		}
1363 		sum += ichdr.freemap[i].size;
1364 	}
1365 
1366 	/*
1367 	 * If there are no holes in the address space of the block,
1368 	 * and we don't have enough freespace, then compaction will do us
1369 	 * no good and we should just give up.
1370 	 */
1371 	if (!ichdr.holes && sum < entsize)
1372 		return -ENOSPC;
1373 
1374 	/*
1375 	 * Compact the entries to coalesce free space.
1376 	 * This may change the hdr->count via dropping INCOMPLETE entries.
1377 	 */
1378 	xfs_attr3_leaf_compact(args, &ichdr, bp);
1379 
1380 	/*
1381 	 * After compaction, the block is guaranteed to have only one
1382 	 * free region, in freemap[0].  If it is not big enough, give up.
1383 	 */
1384 	if (ichdr.freemap[0].size < (entsize + sizeof(xfs_attr_leaf_entry_t))) {
1385 		tmp = -ENOSPC;
1386 		goto out_log_hdr;
1387 	}
1388 
1389 	tmp = xfs_attr3_leaf_add_work(bp, &ichdr, args, 0);
1390 
1391 out_log_hdr:
1392 	xfs_attr3_leaf_hdr_to_disk(args->geo, leaf, &ichdr);
1393 	xfs_trans_log_buf(args->trans, bp,
1394 		XFS_DA_LOGRANGE(leaf, &leaf->hdr,
1395 				xfs_attr3_leaf_hdr_size(leaf)));
1396 	return tmp;
1397 }
1398 
1399 /*
1400  * Add a name to a leaf attribute list structure.
1401  */
1402 STATIC int
1403 xfs_attr3_leaf_add_work(
1404 	struct xfs_buf		*bp,
1405 	struct xfs_attr3_icleaf_hdr *ichdr,
1406 	struct xfs_da_args	*args,
1407 	int			mapindex)
1408 {
1409 	struct xfs_attr_leafblock *leaf;
1410 	struct xfs_attr_leaf_entry *entry;
1411 	struct xfs_attr_leaf_name_local *name_loc;
1412 	struct xfs_attr_leaf_name_remote *name_rmt;
1413 	struct xfs_mount	*mp;
1414 	int			tmp;
1415 	int			i;
1416 
1417 	trace_xfs_attr_leaf_add_work(args);
1418 
1419 	leaf = bp->b_addr;
1420 	ASSERT(mapindex >= 0 && mapindex < XFS_ATTR_LEAF_MAPSIZE);
1421 	ASSERT(args->index >= 0 && args->index <= ichdr->count);
1422 
1423 	/*
1424 	 * Force open some space in the entry array and fill it in.
1425 	 */
1426 	entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
1427 	if (args->index < ichdr->count) {
1428 		tmp  = ichdr->count - args->index;
1429 		tmp *= sizeof(xfs_attr_leaf_entry_t);
1430 		memmove(entry + 1, entry, tmp);
1431 		xfs_trans_log_buf(args->trans, bp,
1432 		    XFS_DA_LOGRANGE(leaf, entry, tmp + sizeof(*entry)));
1433 	}
1434 	ichdr->count++;
1435 
1436 	/*
1437 	 * Allocate space for the new string (at the end of the run).
1438 	 */
1439 	mp = args->trans->t_mountp;
1440 	ASSERT(ichdr->freemap[mapindex].base < args->geo->blksize);
1441 	ASSERT((ichdr->freemap[mapindex].base & 0x3) == 0);
1442 	ASSERT(ichdr->freemap[mapindex].size >=
1443 		xfs_attr_leaf_newentsize(args, NULL));
1444 	ASSERT(ichdr->freemap[mapindex].size < args->geo->blksize);
1445 	ASSERT((ichdr->freemap[mapindex].size & 0x3) == 0);
1446 
1447 	ichdr->freemap[mapindex].size -= xfs_attr_leaf_newentsize(args, &tmp);
1448 
1449 	entry->nameidx = cpu_to_be16(ichdr->freemap[mapindex].base +
1450 				     ichdr->freemap[mapindex].size);
1451 	entry->hashval = cpu_to_be32(args->hashval);
1452 	entry->flags = tmp ? XFS_ATTR_LOCAL : 0;
1453 	entry->flags |= XFS_ATTR_NSP_ARGS_TO_ONDISK(args->flags);
1454 	if (args->op_flags & XFS_DA_OP_RENAME) {
1455 		entry->flags |= XFS_ATTR_INCOMPLETE;
1456 		if ((args->blkno2 == args->blkno) &&
1457 		    (args->index2 <= args->index)) {
1458 			args->index2++;
1459 		}
1460 	}
1461 	xfs_trans_log_buf(args->trans, bp,
1462 			  XFS_DA_LOGRANGE(leaf, entry, sizeof(*entry)));
1463 	ASSERT((args->index == 0) ||
1464 	       (be32_to_cpu(entry->hashval) >= be32_to_cpu((entry-1)->hashval)));
1465 	ASSERT((args->index == ichdr->count - 1) ||
1466 	       (be32_to_cpu(entry->hashval) <= be32_to_cpu((entry+1)->hashval)));
1467 
1468 	/*
1469 	 * For "remote" attribute values, simply note that we need to
1470 	 * allocate space for the "remote" value.  We can't actually
1471 	 * allocate the extents in this transaction, and we can't decide
1472 	 * which blocks they should be as we might allocate more blocks
1473 	 * as part of this transaction (a split operation for example).
1474 	 */
1475 	if (entry->flags & XFS_ATTR_LOCAL) {
1476 		name_loc = xfs_attr3_leaf_name_local(leaf, args->index);
1477 		name_loc->namelen = args->namelen;
1478 		name_loc->valuelen = cpu_to_be16(args->valuelen);
1479 		memcpy((char *)name_loc->nameval, args->name, args->namelen);
1480 		memcpy((char *)&name_loc->nameval[args->namelen], args->value,
1481 				   be16_to_cpu(name_loc->valuelen));
1482 	} else {
1483 		name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
1484 		name_rmt->namelen = args->namelen;
1485 		memcpy((char *)name_rmt->name, args->name, args->namelen);
1486 		entry->flags |= XFS_ATTR_INCOMPLETE;
1487 		/* just in case */
1488 		name_rmt->valuelen = 0;
1489 		name_rmt->valueblk = 0;
1490 		args->rmtblkno = 1;
1491 		args->rmtblkcnt = xfs_attr3_rmt_blocks(mp, args->valuelen);
1492 		args->rmtvaluelen = args->valuelen;
1493 	}
1494 	xfs_trans_log_buf(args->trans, bp,
1495 	     XFS_DA_LOGRANGE(leaf, xfs_attr3_leaf_name(leaf, args->index),
1496 				   xfs_attr_leaf_entsize(leaf, args->index)));
1497 
1498 	/*
1499 	 * Update the control info for this leaf node
1500 	 */
1501 	if (be16_to_cpu(entry->nameidx) < ichdr->firstused)
1502 		ichdr->firstused = be16_to_cpu(entry->nameidx);
1503 
1504 	ASSERT(ichdr->firstused >= ichdr->count * sizeof(xfs_attr_leaf_entry_t)
1505 					+ xfs_attr3_leaf_hdr_size(leaf));
1506 	tmp = (ichdr->count - 1) * sizeof(xfs_attr_leaf_entry_t)
1507 					+ xfs_attr3_leaf_hdr_size(leaf);
1508 
1509 	for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
1510 		if (ichdr->freemap[i].base == tmp) {
1511 			ichdr->freemap[i].base += sizeof(xfs_attr_leaf_entry_t);
1512 			ichdr->freemap[i].size -=
1513 				min_t(uint16_t, ichdr->freemap[i].size,
1514 						sizeof(xfs_attr_leaf_entry_t));
1515 		}
1516 	}
1517 	ichdr->usedbytes += xfs_attr_leaf_entsize(leaf, args->index);
1518 	return 0;
1519 }
1520 
1521 /*
1522  * Garbage collect a leaf attribute list block by copying it to a new buffer.
1523  */
1524 STATIC void
1525 xfs_attr3_leaf_compact(
1526 	struct xfs_da_args	*args,
1527 	struct xfs_attr3_icleaf_hdr *ichdr_dst,
1528 	struct xfs_buf		*bp)
1529 {
1530 	struct xfs_attr_leafblock *leaf_src;
1531 	struct xfs_attr_leafblock *leaf_dst;
1532 	struct xfs_attr3_icleaf_hdr ichdr_src;
1533 	struct xfs_trans	*trans = args->trans;
1534 	char			*tmpbuffer;
1535 
1536 	trace_xfs_attr_leaf_compact(args);
1537 
1538 	tmpbuffer = kmem_alloc(args->geo->blksize, 0);
1539 	memcpy(tmpbuffer, bp->b_addr, args->geo->blksize);
1540 	memset(bp->b_addr, 0, args->geo->blksize);
1541 	leaf_src = (xfs_attr_leafblock_t *)tmpbuffer;
1542 	leaf_dst = bp->b_addr;
1543 
1544 	/*
1545 	 * Copy the on-disk header back into the destination buffer to ensure
1546 	 * all the information in the header that is not part of the incore
1547 	 * header structure is preserved.
1548 	 */
1549 	memcpy(bp->b_addr, tmpbuffer, xfs_attr3_leaf_hdr_size(leaf_src));
1550 
1551 	/* Initialise the incore headers */
1552 	ichdr_src = *ichdr_dst;	/* struct copy */
1553 	ichdr_dst->firstused = args->geo->blksize;
1554 	ichdr_dst->usedbytes = 0;
1555 	ichdr_dst->count = 0;
1556 	ichdr_dst->holes = 0;
1557 	ichdr_dst->freemap[0].base = xfs_attr3_leaf_hdr_size(leaf_src);
1558 	ichdr_dst->freemap[0].size = ichdr_dst->firstused -
1559 						ichdr_dst->freemap[0].base;
1560 
1561 	/* write the header back to initialise the underlying buffer */
1562 	xfs_attr3_leaf_hdr_to_disk(args->geo, leaf_dst, ichdr_dst);
1563 
1564 	/*
1565 	 * Copy all entry's in the same (sorted) order,
1566 	 * but allocate name/value pairs packed and in sequence.
1567 	 */
1568 	xfs_attr3_leaf_moveents(args, leaf_src, &ichdr_src, 0,
1569 				leaf_dst, ichdr_dst, 0, ichdr_src.count);
1570 	/*
1571 	 * this logs the entire buffer, but the caller must write the header
1572 	 * back to the buffer when it is finished modifying it.
1573 	 */
1574 	xfs_trans_log_buf(trans, bp, 0, args->geo->blksize - 1);
1575 
1576 	kmem_free(tmpbuffer);
1577 }
1578 
1579 /*
1580  * Compare two leaf blocks "order".
1581  * Return 0 unless leaf2 should go before leaf1.
1582  */
1583 static int
1584 xfs_attr3_leaf_order(
1585 	struct xfs_buf	*leaf1_bp,
1586 	struct xfs_attr3_icleaf_hdr *leaf1hdr,
1587 	struct xfs_buf	*leaf2_bp,
1588 	struct xfs_attr3_icleaf_hdr *leaf2hdr)
1589 {
1590 	struct xfs_attr_leaf_entry *entries1;
1591 	struct xfs_attr_leaf_entry *entries2;
1592 
1593 	entries1 = xfs_attr3_leaf_entryp(leaf1_bp->b_addr);
1594 	entries2 = xfs_attr3_leaf_entryp(leaf2_bp->b_addr);
1595 	if (leaf1hdr->count > 0 && leaf2hdr->count > 0 &&
1596 	    ((be32_to_cpu(entries2[0].hashval) <
1597 	      be32_to_cpu(entries1[0].hashval)) ||
1598 	     (be32_to_cpu(entries2[leaf2hdr->count - 1].hashval) <
1599 	      be32_to_cpu(entries1[leaf1hdr->count - 1].hashval)))) {
1600 		return 1;
1601 	}
1602 	return 0;
1603 }
1604 
1605 int
1606 xfs_attr_leaf_order(
1607 	struct xfs_buf	*leaf1_bp,
1608 	struct xfs_buf	*leaf2_bp)
1609 {
1610 	struct xfs_attr3_icleaf_hdr ichdr1;
1611 	struct xfs_attr3_icleaf_hdr ichdr2;
1612 	struct xfs_mount *mp = leaf1_bp->b_mount;
1613 
1614 	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr1, leaf1_bp->b_addr);
1615 	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr2, leaf2_bp->b_addr);
1616 	return xfs_attr3_leaf_order(leaf1_bp, &ichdr1, leaf2_bp, &ichdr2);
1617 }
1618 
1619 /*
1620  * Redistribute the attribute list entries between two leaf nodes,
1621  * taking into account the size of the new entry.
1622  *
1623  * NOTE: if new block is empty, then it will get the upper half of the
1624  * old block.  At present, all (one) callers pass in an empty second block.
1625  *
1626  * This code adjusts the args->index/blkno and args->index2/blkno2 fields
1627  * to match what it is doing in splitting the attribute leaf block.  Those
1628  * values are used in "atomic rename" operations on attributes.  Note that
1629  * the "new" and "old" values can end up in different blocks.
1630  */
1631 STATIC void
1632 xfs_attr3_leaf_rebalance(
1633 	struct xfs_da_state	*state,
1634 	struct xfs_da_state_blk	*blk1,
1635 	struct xfs_da_state_blk	*blk2)
1636 {
1637 	struct xfs_da_args	*args;
1638 	struct xfs_attr_leafblock *leaf1;
1639 	struct xfs_attr_leafblock *leaf2;
1640 	struct xfs_attr3_icleaf_hdr ichdr1;
1641 	struct xfs_attr3_icleaf_hdr ichdr2;
1642 	struct xfs_attr_leaf_entry *entries1;
1643 	struct xfs_attr_leaf_entry *entries2;
1644 	int			count;
1645 	int			totallen;
1646 	int			max;
1647 	int			space;
1648 	int			swap;
1649 
1650 	/*
1651 	 * Set up environment.
1652 	 */
1653 	ASSERT(blk1->magic == XFS_ATTR_LEAF_MAGIC);
1654 	ASSERT(blk2->magic == XFS_ATTR_LEAF_MAGIC);
1655 	leaf1 = blk1->bp->b_addr;
1656 	leaf2 = blk2->bp->b_addr;
1657 	xfs_attr3_leaf_hdr_from_disk(state->args->geo, &ichdr1, leaf1);
1658 	xfs_attr3_leaf_hdr_from_disk(state->args->geo, &ichdr2, leaf2);
1659 	ASSERT(ichdr2.count == 0);
1660 	args = state->args;
1661 
1662 	trace_xfs_attr_leaf_rebalance(args);
1663 
1664 	/*
1665 	 * Check ordering of blocks, reverse if it makes things simpler.
1666 	 *
1667 	 * NOTE: Given that all (current) callers pass in an empty
1668 	 * second block, this code should never set "swap".
1669 	 */
1670 	swap = 0;
1671 	if (xfs_attr3_leaf_order(blk1->bp, &ichdr1, blk2->bp, &ichdr2)) {
1672 		swap(blk1, blk2);
1673 
1674 		/* swap structures rather than reconverting them */
1675 		swap(ichdr1, ichdr2);
1676 
1677 		leaf1 = blk1->bp->b_addr;
1678 		leaf2 = blk2->bp->b_addr;
1679 		swap = 1;
1680 	}
1681 
1682 	/*
1683 	 * Examine entries until we reduce the absolute difference in
1684 	 * byte usage between the two blocks to a minimum.  Then get
1685 	 * the direction to copy and the number of elements to move.
1686 	 *
1687 	 * "inleaf" is true if the new entry should be inserted into blk1.
1688 	 * If "swap" is also true, then reverse the sense of "inleaf".
1689 	 */
1690 	state->inleaf = xfs_attr3_leaf_figure_balance(state, blk1, &ichdr1,
1691 						      blk2, &ichdr2,
1692 						      &count, &totallen);
1693 	if (swap)
1694 		state->inleaf = !state->inleaf;
1695 
1696 	/*
1697 	 * Move any entries required from leaf to leaf:
1698 	 */
1699 	if (count < ichdr1.count) {
1700 		/*
1701 		 * Figure the total bytes to be added to the destination leaf.
1702 		 */
1703 		/* number entries being moved */
1704 		count = ichdr1.count - count;
1705 		space  = ichdr1.usedbytes - totallen;
1706 		space += count * sizeof(xfs_attr_leaf_entry_t);
1707 
1708 		/*
1709 		 * leaf2 is the destination, compact it if it looks tight.
1710 		 */
1711 		max  = ichdr2.firstused - xfs_attr3_leaf_hdr_size(leaf1);
1712 		max -= ichdr2.count * sizeof(xfs_attr_leaf_entry_t);
1713 		if (space > max)
1714 			xfs_attr3_leaf_compact(args, &ichdr2, blk2->bp);
1715 
1716 		/*
1717 		 * Move high entries from leaf1 to low end of leaf2.
1718 		 */
1719 		xfs_attr3_leaf_moveents(args, leaf1, &ichdr1,
1720 				ichdr1.count - count, leaf2, &ichdr2, 0, count);
1721 
1722 	} else if (count > ichdr1.count) {
1723 		/*
1724 		 * I assert that since all callers pass in an empty
1725 		 * second buffer, this code should never execute.
1726 		 */
1727 		ASSERT(0);
1728 
1729 		/*
1730 		 * Figure the total bytes to be added to the destination leaf.
1731 		 */
1732 		/* number entries being moved */
1733 		count -= ichdr1.count;
1734 		space  = totallen - ichdr1.usedbytes;
1735 		space += count * sizeof(xfs_attr_leaf_entry_t);
1736 
1737 		/*
1738 		 * leaf1 is the destination, compact it if it looks tight.
1739 		 */
1740 		max  = ichdr1.firstused - xfs_attr3_leaf_hdr_size(leaf1);
1741 		max -= ichdr1.count * sizeof(xfs_attr_leaf_entry_t);
1742 		if (space > max)
1743 			xfs_attr3_leaf_compact(args, &ichdr1, blk1->bp);
1744 
1745 		/*
1746 		 * Move low entries from leaf2 to high end of leaf1.
1747 		 */
1748 		xfs_attr3_leaf_moveents(args, leaf2, &ichdr2, 0, leaf1, &ichdr1,
1749 					ichdr1.count, count);
1750 	}
1751 
1752 	xfs_attr3_leaf_hdr_to_disk(state->args->geo, leaf1, &ichdr1);
1753 	xfs_attr3_leaf_hdr_to_disk(state->args->geo, leaf2, &ichdr2);
1754 	xfs_trans_log_buf(args->trans, blk1->bp, 0, args->geo->blksize - 1);
1755 	xfs_trans_log_buf(args->trans, blk2->bp, 0, args->geo->blksize - 1);
1756 
1757 	/*
1758 	 * Copy out last hashval in each block for B-tree code.
1759 	 */
1760 	entries1 = xfs_attr3_leaf_entryp(leaf1);
1761 	entries2 = xfs_attr3_leaf_entryp(leaf2);
1762 	blk1->hashval = be32_to_cpu(entries1[ichdr1.count - 1].hashval);
1763 	blk2->hashval = be32_to_cpu(entries2[ichdr2.count - 1].hashval);
1764 
1765 	/*
1766 	 * Adjust the expected index for insertion.
1767 	 * NOTE: this code depends on the (current) situation that the
1768 	 * second block was originally empty.
1769 	 *
1770 	 * If the insertion point moved to the 2nd block, we must adjust
1771 	 * the index.  We must also track the entry just following the
1772 	 * new entry for use in an "atomic rename" operation, that entry
1773 	 * is always the "old" entry and the "new" entry is what we are
1774 	 * inserting.  The index/blkno fields refer to the "old" entry,
1775 	 * while the index2/blkno2 fields refer to the "new" entry.
1776 	 */
1777 	if (blk1->index > ichdr1.count) {
1778 		ASSERT(state->inleaf == 0);
1779 		blk2->index = blk1->index - ichdr1.count;
1780 		args->index = args->index2 = blk2->index;
1781 		args->blkno = args->blkno2 = blk2->blkno;
1782 	} else if (blk1->index == ichdr1.count) {
1783 		if (state->inleaf) {
1784 			args->index = blk1->index;
1785 			args->blkno = blk1->blkno;
1786 			args->index2 = 0;
1787 			args->blkno2 = blk2->blkno;
1788 		} else {
1789 			/*
1790 			 * On a double leaf split, the original attr location
1791 			 * is already stored in blkno2/index2, so don't
1792 			 * overwrite it overwise we corrupt the tree.
1793 			 */
1794 			blk2->index = blk1->index - ichdr1.count;
1795 			args->index = blk2->index;
1796 			args->blkno = blk2->blkno;
1797 			if (!state->extravalid) {
1798 				/*
1799 				 * set the new attr location to match the old
1800 				 * one and let the higher level split code
1801 				 * decide where in the leaf to place it.
1802 				 */
1803 				args->index2 = blk2->index;
1804 				args->blkno2 = blk2->blkno;
1805 			}
1806 		}
1807 	} else {
1808 		ASSERT(state->inleaf == 1);
1809 		args->index = args->index2 = blk1->index;
1810 		args->blkno = args->blkno2 = blk1->blkno;
1811 	}
1812 }
1813 
1814 /*
1815  * Examine entries until we reduce the absolute difference in
1816  * byte usage between the two blocks to a minimum.
1817  * GROT: Is this really necessary?  With other than a 512 byte blocksize,
1818  * GROT: there will always be enough room in either block for a new entry.
1819  * GROT: Do a double-split for this case?
1820  */
1821 STATIC int
1822 xfs_attr3_leaf_figure_balance(
1823 	struct xfs_da_state		*state,
1824 	struct xfs_da_state_blk		*blk1,
1825 	struct xfs_attr3_icleaf_hdr	*ichdr1,
1826 	struct xfs_da_state_blk		*blk2,
1827 	struct xfs_attr3_icleaf_hdr	*ichdr2,
1828 	int				*countarg,
1829 	int				*usedbytesarg)
1830 {
1831 	struct xfs_attr_leafblock	*leaf1 = blk1->bp->b_addr;
1832 	struct xfs_attr_leafblock	*leaf2 = blk2->bp->b_addr;
1833 	struct xfs_attr_leaf_entry	*entry;
1834 	int				count;
1835 	int				max;
1836 	int				index;
1837 	int				totallen = 0;
1838 	int				half;
1839 	int				lastdelta;
1840 	int				foundit = 0;
1841 	int				tmp;
1842 
1843 	/*
1844 	 * Examine entries until we reduce the absolute difference in
1845 	 * byte usage between the two blocks to a minimum.
1846 	 */
1847 	max = ichdr1->count + ichdr2->count;
1848 	half = (max + 1) * sizeof(*entry);
1849 	half += ichdr1->usedbytes + ichdr2->usedbytes +
1850 			xfs_attr_leaf_newentsize(state->args, NULL);
1851 	half /= 2;
1852 	lastdelta = state->args->geo->blksize;
1853 	entry = xfs_attr3_leaf_entryp(leaf1);
1854 	for (count = index = 0; count < max; entry++, index++, count++) {
1855 
1856 #define XFS_ATTR_ABS(A)	(((A) < 0) ? -(A) : (A))
1857 		/*
1858 		 * The new entry is in the first block, account for it.
1859 		 */
1860 		if (count == blk1->index) {
1861 			tmp = totallen + sizeof(*entry) +
1862 				xfs_attr_leaf_newentsize(state->args, NULL);
1863 			if (XFS_ATTR_ABS(half - tmp) > lastdelta)
1864 				break;
1865 			lastdelta = XFS_ATTR_ABS(half - tmp);
1866 			totallen = tmp;
1867 			foundit = 1;
1868 		}
1869 
1870 		/*
1871 		 * Wrap around into the second block if necessary.
1872 		 */
1873 		if (count == ichdr1->count) {
1874 			leaf1 = leaf2;
1875 			entry = xfs_attr3_leaf_entryp(leaf1);
1876 			index = 0;
1877 		}
1878 
1879 		/*
1880 		 * Figure out if next leaf entry would be too much.
1881 		 */
1882 		tmp = totallen + sizeof(*entry) + xfs_attr_leaf_entsize(leaf1,
1883 									index);
1884 		if (XFS_ATTR_ABS(half - tmp) > lastdelta)
1885 			break;
1886 		lastdelta = XFS_ATTR_ABS(half - tmp);
1887 		totallen = tmp;
1888 #undef XFS_ATTR_ABS
1889 	}
1890 
1891 	/*
1892 	 * Calculate the number of usedbytes that will end up in lower block.
1893 	 * If new entry not in lower block, fix up the count.
1894 	 */
1895 	totallen -= count * sizeof(*entry);
1896 	if (foundit) {
1897 		totallen -= sizeof(*entry) +
1898 				xfs_attr_leaf_newentsize(state->args, NULL);
1899 	}
1900 
1901 	*countarg = count;
1902 	*usedbytesarg = totallen;
1903 	return foundit;
1904 }
1905 
1906 /*========================================================================
1907  * Routines used for shrinking the Btree.
1908  *========================================================================*/
1909 
1910 /*
1911  * Check a leaf block and its neighbors to see if the block should be
1912  * collapsed into one or the other neighbor.  Always keep the block
1913  * with the smaller block number.
1914  * If the current block is over 50% full, don't try to join it, return 0.
1915  * If the block is empty, fill in the state structure and return 2.
1916  * If it can be collapsed, fill in the state structure and return 1.
1917  * If nothing can be done, return 0.
1918  *
1919  * GROT: allow for INCOMPLETE entries in calculation.
1920  */
1921 int
1922 xfs_attr3_leaf_toosmall(
1923 	struct xfs_da_state	*state,
1924 	int			*action)
1925 {
1926 	struct xfs_attr_leafblock *leaf;
1927 	struct xfs_da_state_blk	*blk;
1928 	struct xfs_attr3_icleaf_hdr ichdr;
1929 	struct xfs_buf		*bp;
1930 	xfs_dablk_t		blkno;
1931 	int			bytes;
1932 	int			forward;
1933 	int			error;
1934 	int			retval;
1935 	int			i;
1936 
1937 	trace_xfs_attr_leaf_toosmall(state->args);
1938 
1939 	/*
1940 	 * Check for the degenerate case of the block being over 50% full.
1941 	 * If so, it's not worth even looking to see if we might be able
1942 	 * to coalesce with a sibling.
1943 	 */
1944 	blk = &state->path.blk[ state->path.active-1 ];
1945 	leaf = blk->bp->b_addr;
1946 	xfs_attr3_leaf_hdr_from_disk(state->args->geo, &ichdr, leaf);
1947 	bytes = xfs_attr3_leaf_hdr_size(leaf) +
1948 		ichdr.count * sizeof(xfs_attr_leaf_entry_t) +
1949 		ichdr.usedbytes;
1950 	if (bytes > (state->args->geo->blksize >> 1)) {
1951 		*action = 0;	/* blk over 50%, don't try to join */
1952 		return 0;
1953 	}
1954 
1955 	/*
1956 	 * Check for the degenerate case of the block being empty.
1957 	 * If the block is empty, we'll simply delete it, no need to
1958 	 * coalesce it with a sibling block.  We choose (arbitrarily)
1959 	 * to merge with the forward block unless it is NULL.
1960 	 */
1961 	if (ichdr.count == 0) {
1962 		/*
1963 		 * Make altpath point to the block we want to keep and
1964 		 * path point to the block we want to drop (this one).
1965 		 */
1966 		forward = (ichdr.forw != 0);
1967 		memcpy(&state->altpath, &state->path, sizeof(state->path));
1968 		error = xfs_da3_path_shift(state, &state->altpath, forward,
1969 						 0, &retval);
1970 		if (error)
1971 			return error;
1972 		if (retval) {
1973 			*action = 0;
1974 		} else {
1975 			*action = 2;
1976 		}
1977 		return 0;
1978 	}
1979 
1980 	/*
1981 	 * Examine each sibling block to see if we can coalesce with
1982 	 * at least 25% free space to spare.  We need to figure out
1983 	 * whether to merge with the forward or the backward block.
1984 	 * We prefer coalescing with the lower numbered sibling so as
1985 	 * to shrink an attribute list over time.
1986 	 */
1987 	/* start with smaller blk num */
1988 	forward = ichdr.forw < ichdr.back;
1989 	for (i = 0; i < 2; forward = !forward, i++) {
1990 		struct xfs_attr3_icleaf_hdr ichdr2;
1991 		if (forward)
1992 			blkno = ichdr.forw;
1993 		else
1994 			blkno = ichdr.back;
1995 		if (blkno == 0)
1996 			continue;
1997 		error = xfs_attr3_leaf_read(state->args->trans, state->args->dp,
1998 					blkno, &bp);
1999 		if (error)
2000 			return error;
2001 
2002 		xfs_attr3_leaf_hdr_from_disk(state->args->geo, &ichdr2, bp->b_addr);
2003 
2004 		bytes = state->args->geo->blksize -
2005 			(state->args->geo->blksize >> 2) -
2006 			ichdr.usedbytes - ichdr2.usedbytes -
2007 			((ichdr.count + ichdr2.count) *
2008 					sizeof(xfs_attr_leaf_entry_t)) -
2009 			xfs_attr3_leaf_hdr_size(leaf);
2010 
2011 		xfs_trans_brelse(state->args->trans, bp);
2012 		if (bytes >= 0)
2013 			break;	/* fits with at least 25% to spare */
2014 	}
2015 	if (i >= 2) {
2016 		*action = 0;
2017 		return 0;
2018 	}
2019 
2020 	/*
2021 	 * Make altpath point to the block we want to keep (the lower
2022 	 * numbered block) and path point to the block we want to drop.
2023 	 */
2024 	memcpy(&state->altpath, &state->path, sizeof(state->path));
2025 	if (blkno < blk->blkno) {
2026 		error = xfs_da3_path_shift(state, &state->altpath, forward,
2027 						 0, &retval);
2028 	} else {
2029 		error = xfs_da3_path_shift(state, &state->path, forward,
2030 						 0, &retval);
2031 	}
2032 	if (error)
2033 		return error;
2034 	if (retval) {
2035 		*action = 0;
2036 	} else {
2037 		*action = 1;
2038 	}
2039 	return 0;
2040 }
2041 
2042 /*
2043  * Remove a name from the leaf attribute list structure.
2044  *
2045  * Return 1 if leaf is less than 37% full, 0 if >= 37% full.
2046  * If two leaves are 37% full, when combined they will leave 25% free.
2047  */
2048 int
2049 xfs_attr3_leaf_remove(
2050 	struct xfs_buf		*bp,
2051 	struct xfs_da_args	*args)
2052 {
2053 	struct xfs_attr_leafblock *leaf;
2054 	struct xfs_attr3_icleaf_hdr ichdr;
2055 	struct xfs_attr_leaf_entry *entry;
2056 	int			before;
2057 	int			after;
2058 	int			smallest;
2059 	int			entsize;
2060 	int			tablesize;
2061 	int			tmp;
2062 	int			i;
2063 
2064 	trace_xfs_attr_leaf_remove(args);
2065 
2066 	leaf = bp->b_addr;
2067 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
2068 
2069 	ASSERT(ichdr.count > 0 && ichdr.count < args->geo->blksize / 8);
2070 	ASSERT(args->index >= 0 && args->index < ichdr.count);
2071 	ASSERT(ichdr.firstused >= ichdr.count * sizeof(*entry) +
2072 					xfs_attr3_leaf_hdr_size(leaf));
2073 
2074 	entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
2075 
2076 	ASSERT(be16_to_cpu(entry->nameidx) >= ichdr.firstused);
2077 	ASSERT(be16_to_cpu(entry->nameidx) < args->geo->blksize);
2078 
2079 	/*
2080 	 * Scan through free region table:
2081 	 *    check for adjacency of free'd entry with an existing one,
2082 	 *    find smallest free region in case we need to replace it,
2083 	 *    adjust any map that borders the entry table,
2084 	 */
2085 	tablesize = ichdr.count * sizeof(xfs_attr_leaf_entry_t)
2086 					+ xfs_attr3_leaf_hdr_size(leaf);
2087 	tmp = ichdr.freemap[0].size;
2088 	before = after = -1;
2089 	smallest = XFS_ATTR_LEAF_MAPSIZE - 1;
2090 	entsize = xfs_attr_leaf_entsize(leaf, args->index);
2091 	for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
2092 		ASSERT(ichdr.freemap[i].base < args->geo->blksize);
2093 		ASSERT(ichdr.freemap[i].size < args->geo->blksize);
2094 		if (ichdr.freemap[i].base == tablesize) {
2095 			ichdr.freemap[i].base -= sizeof(xfs_attr_leaf_entry_t);
2096 			ichdr.freemap[i].size += sizeof(xfs_attr_leaf_entry_t);
2097 		}
2098 
2099 		if (ichdr.freemap[i].base + ichdr.freemap[i].size ==
2100 				be16_to_cpu(entry->nameidx)) {
2101 			before = i;
2102 		} else if (ichdr.freemap[i].base ==
2103 				(be16_to_cpu(entry->nameidx) + entsize)) {
2104 			after = i;
2105 		} else if (ichdr.freemap[i].size < tmp) {
2106 			tmp = ichdr.freemap[i].size;
2107 			smallest = i;
2108 		}
2109 	}
2110 
2111 	/*
2112 	 * Coalesce adjacent freemap regions,
2113 	 * or replace the smallest region.
2114 	 */
2115 	if ((before >= 0) || (after >= 0)) {
2116 		if ((before >= 0) && (after >= 0)) {
2117 			ichdr.freemap[before].size += entsize;
2118 			ichdr.freemap[before].size += ichdr.freemap[after].size;
2119 			ichdr.freemap[after].base = 0;
2120 			ichdr.freemap[after].size = 0;
2121 		} else if (before >= 0) {
2122 			ichdr.freemap[before].size += entsize;
2123 		} else {
2124 			ichdr.freemap[after].base = be16_to_cpu(entry->nameidx);
2125 			ichdr.freemap[after].size += entsize;
2126 		}
2127 	} else {
2128 		/*
2129 		 * Replace smallest region (if it is smaller than free'd entry)
2130 		 */
2131 		if (ichdr.freemap[smallest].size < entsize) {
2132 			ichdr.freemap[smallest].base = be16_to_cpu(entry->nameidx);
2133 			ichdr.freemap[smallest].size = entsize;
2134 		}
2135 	}
2136 
2137 	/*
2138 	 * Did we remove the first entry?
2139 	 */
2140 	if (be16_to_cpu(entry->nameidx) == ichdr.firstused)
2141 		smallest = 1;
2142 	else
2143 		smallest = 0;
2144 
2145 	/*
2146 	 * Compress the remaining entries and zero out the removed stuff.
2147 	 */
2148 	memset(xfs_attr3_leaf_name(leaf, args->index), 0, entsize);
2149 	ichdr.usedbytes -= entsize;
2150 	xfs_trans_log_buf(args->trans, bp,
2151 	     XFS_DA_LOGRANGE(leaf, xfs_attr3_leaf_name(leaf, args->index),
2152 				   entsize));
2153 
2154 	tmp = (ichdr.count - args->index) * sizeof(xfs_attr_leaf_entry_t);
2155 	memmove(entry, entry + 1, tmp);
2156 	ichdr.count--;
2157 	xfs_trans_log_buf(args->trans, bp,
2158 	    XFS_DA_LOGRANGE(leaf, entry, tmp + sizeof(xfs_attr_leaf_entry_t)));
2159 
2160 	entry = &xfs_attr3_leaf_entryp(leaf)[ichdr.count];
2161 	memset(entry, 0, sizeof(xfs_attr_leaf_entry_t));
2162 
2163 	/*
2164 	 * If we removed the first entry, re-find the first used byte
2165 	 * in the name area.  Note that if the entry was the "firstused",
2166 	 * then we don't have a "hole" in our block resulting from
2167 	 * removing the name.
2168 	 */
2169 	if (smallest) {
2170 		tmp = args->geo->blksize;
2171 		entry = xfs_attr3_leaf_entryp(leaf);
2172 		for (i = ichdr.count - 1; i >= 0; entry++, i--) {
2173 			ASSERT(be16_to_cpu(entry->nameidx) >= ichdr.firstused);
2174 			ASSERT(be16_to_cpu(entry->nameidx) < args->geo->blksize);
2175 
2176 			if (be16_to_cpu(entry->nameidx) < tmp)
2177 				tmp = be16_to_cpu(entry->nameidx);
2178 		}
2179 		ichdr.firstused = tmp;
2180 		ASSERT(ichdr.firstused != 0);
2181 	} else {
2182 		ichdr.holes = 1;	/* mark as needing compaction */
2183 	}
2184 	xfs_attr3_leaf_hdr_to_disk(args->geo, leaf, &ichdr);
2185 	xfs_trans_log_buf(args->trans, bp,
2186 			  XFS_DA_LOGRANGE(leaf, &leaf->hdr,
2187 					  xfs_attr3_leaf_hdr_size(leaf)));
2188 
2189 	/*
2190 	 * Check if leaf is less than 50% full, caller may want to
2191 	 * "join" the leaf with a sibling if so.
2192 	 */
2193 	tmp = ichdr.usedbytes + xfs_attr3_leaf_hdr_size(leaf) +
2194 	      ichdr.count * sizeof(xfs_attr_leaf_entry_t);
2195 
2196 	return tmp < args->geo->magicpct; /* leaf is < 37% full */
2197 }
2198 
2199 /*
2200  * Move all the attribute list entries from drop_leaf into save_leaf.
2201  */
2202 void
2203 xfs_attr3_leaf_unbalance(
2204 	struct xfs_da_state	*state,
2205 	struct xfs_da_state_blk	*drop_blk,
2206 	struct xfs_da_state_blk	*save_blk)
2207 {
2208 	struct xfs_attr_leafblock *drop_leaf = drop_blk->bp->b_addr;
2209 	struct xfs_attr_leafblock *save_leaf = save_blk->bp->b_addr;
2210 	struct xfs_attr3_icleaf_hdr drophdr;
2211 	struct xfs_attr3_icleaf_hdr savehdr;
2212 	struct xfs_attr_leaf_entry *entry;
2213 
2214 	trace_xfs_attr_leaf_unbalance(state->args);
2215 
2216 	drop_leaf = drop_blk->bp->b_addr;
2217 	save_leaf = save_blk->bp->b_addr;
2218 	xfs_attr3_leaf_hdr_from_disk(state->args->geo, &drophdr, drop_leaf);
2219 	xfs_attr3_leaf_hdr_from_disk(state->args->geo, &savehdr, save_leaf);
2220 	entry = xfs_attr3_leaf_entryp(drop_leaf);
2221 
2222 	/*
2223 	 * Save last hashval from dying block for later Btree fixup.
2224 	 */
2225 	drop_blk->hashval = be32_to_cpu(entry[drophdr.count - 1].hashval);
2226 
2227 	/*
2228 	 * Check if we need a temp buffer, or can we do it in place.
2229 	 * Note that we don't check "leaf" for holes because we will
2230 	 * always be dropping it, toosmall() decided that for us already.
2231 	 */
2232 	if (savehdr.holes == 0) {
2233 		/*
2234 		 * dest leaf has no holes, so we add there.  May need
2235 		 * to make some room in the entry array.
2236 		 */
2237 		if (xfs_attr3_leaf_order(save_blk->bp, &savehdr,
2238 					 drop_blk->bp, &drophdr)) {
2239 			xfs_attr3_leaf_moveents(state->args,
2240 						drop_leaf, &drophdr, 0,
2241 						save_leaf, &savehdr, 0,
2242 						drophdr.count);
2243 		} else {
2244 			xfs_attr3_leaf_moveents(state->args,
2245 						drop_leaf, &drophdr, 0,
2246 						save_leaf, &savehdr,
2247 						savehdr.count, drophdr.count);
2248 		}
2249 	} else {
2250 		/*
2251 		 * Destination has holes, so we make a temporary copy
2252 		 * of the leaf and add them both to that.
2253 		 */
2254 		struct xfs_attr_leafblock *tmp_leaf;
2255 		struct xfs_attr3_icleaf_hdr tmphdr;
2256 
2257 		tmp_leaf = kmem_zalloc(state->args->geo->blksize, 0);
2258 
2259 		/*
2260 		 * Copy the header into the temp leaf so that all the stuff
2261 		 * not in the incore header is present and gets copied back in
2262 		 * once we've moved all the entries.
2263 		 */
2264 		memcpy(tmp_leaf, save_leaf, xfs_attr3_leaf_hdr_size(save_leaf));
2265 
2266 		memset(&tmphdr, 0, sizeof(tmphdr));
2267 		tmphdr.magic = savehdr.magic;
2268 		tmphdr.forw = savehdr.forw;
2269 		tmphdr.back = savehdr.back;
2270 		tmphdr.firstused = state->args->geo->blksize;
2271 
2272 		/* write the header to the temp buffer to initialise it */
2273 		xfs_attr3_leaf_hdr_to_disk(state->args->geo, tmp_leaf, &tmphdr);
2274 
2275 		if (xfs_attr3_leaf_order(save_blk->bp, &savehdr,
2276 					 drop_blk->bp, &drophdr)) {
2277 			xfs_attr3_leaf_moveents(state->args,
2278 						drop_leaf, &drophdr, 0,
2279 						tmp_leaf, &tmphdr, 0,
2280 						drophdr.count);
2281 			xfs_attr3_leaf_moveents(state->args,
2282 						save_leaf, &savehdr, 0,
2283 						tmp_leaf, &tmphdr, tmphdr.count,
2284 						savehdr.count);
2285 		} else {
2286 			xfs_attr3_leaf_moveents(state->args,
2287 						save_leaf, &savehdr, 0,
2288 						tmp_leaf, &tmphdr, 0,
2289 						savehdr.count);
2290 			xfs_attr3_leaf_moveents(state->args,
2291 						drop_leaf, &drophdr, 0,
2292 						tmp_leaf, &tmphdr, tmphdr.count,
2293 						drophdr.count);
2294 		}
2295 		memcpy(save_leaf, tmp_leaf, state->args->geo->blksize);
2296 		savehdr = tmphdr; /* struct copy */
2297 		kmem_free(tmp_leaf);
2298 	}
2299 
2300 	xfs_attr3_leaf_hdr_to_disk(state->args->geo, save_leaf, &savehdr);
2301 	xfs_trans_log_buf(state->args->trans, save_blk->bp, 0,
2302 					   state->args->geo->blksize - 1);
2303 
2304 	/*
2305 	 * Copy out last hashval in each block for B-tree code.
2306 	 */
2307 	entry = xfs_attr3_leaf_entryp(save_leaf);
2308 	save_blk->hashval = be32_to_cpu(entry[savehdr.count - 1].hashval);
2309 }
2310 
2311 /*========================================================================
2312  * Routines used for finding things in the Btree.
2313  *========================================================================*/
2314 
2315 /*
2316  * Look up a name in a leaf attribute list structure.
2317  * This is the internal routine, it uses the caller's buffer.
2318  *
2319  * Note that duplicate keys are allowed, but only check within the
2320  * current leaf node.  The Btree code must check in adjacent leaf nodes.
2321  *
2322  * Return in args->index the index into the entry[] array of either
2323  * the found entry, or where the entry should have been (insert before
2324  * that entry).
2325  *
2326  * Don't change the args->value unless we find the attribute.
2327  */
2328 int
2329 xfs_attr3_leaf_lookup_int(
2330 	struct xfs_buf		*bp,
2331 	struct xfs_da_args	*args)
2332 {
2333 	struct xfs_attr_leafblock *leaf;
2334 	struct xfs_attr3_icleaf_hdr ichdr;
2335 	struct xfs_attr_leaf_entry *entry;
2336 	struct xfs_attr_leaf_entry *entries;
2337 	struct xfs_attr_leaf_name_local *name_loc;
2338 	struct xfs_attr_leaf_name_remote *name_rmt;
2339 	xfs_dahash_t		hashval;
2340 	int			probe;
2341 	int			span;
2342 
2343 	trace_xfs_attr_leaf_lookup(args);
2344 
2345 	leaf = bp->b_addr;
2346 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
2347 	entries = xfs_attr3_leaf_entryp(leaf);
2348 	if (ichdr.count >= args->geo->blksize / 8) {
2349 		xfs_buf_corruption_error(bp);
2350 		return -EFSCORRUPTED;
2351 	}
2352 
2353 	/*
2354 	 * Binary search.  (note: small blocks will skip this loop)
2355 	 */
2356 	hashval = args->hashval;
2357 	probe = span = ichdr.count / 2;
2358 	for (entry = &entries[probe]; span > 4; entry = &entries[probe]) {
2359 		span /= 2;
2360 		if (be32_to_cpu(entry->hashval) < hashval)
2361 			probe += span;
2362 		else if (be32_to_cpu(entry->hashval) > hashval)
2363 			probe -= span;
2364 		else
2365 			break;
2366 	}
2367 	if (!(probe >= 0 && (!ichdr.count || probe < ichdr.count))) {
2368 		xfs_buf_corruption_error(bp);
2369 		return -EFSCORRUPTED;
2370 	}
2371 	if (!(span <= 4 || be32_to_cpu(entry->hashval) == hashval)) {
2372 		xfs_buf_corruption_error(bp);
2373 		return -EFSCORRUPTED;
2374 	}
2375 
2376 	/*
2377 	 * Since we may have duplicate hashval's, find the first matching
2378 	 * hashval in the leaf.
2379 	 */
2380 	while (probe > 0 && be32_to_cpu(entry->hashval) >= hashval) {
2381 		entry--;
2382 		probe--;
2383 	}
2384 	while (probe < ichdr.count &&
2385 	       be32_to_cpu(entry->hashval) < hashval) {
2386 		entry++;
2387 		probe++;
2388 	}
2389 	if (probe == ichdr.count || be32_to_cpu(entry->hashval) != hashval) {
2390 		args->index = probe;
2391 		return -ENOATTR;
2392 	}
2393 
2394 	/*
2395 	 * Duplicate keys may be present, so search all of them for a match.
2396 	 */
2397 	for (; probe < ichdr.count && (be32_to_cpu(entry->hashval) == hashval);
2398 			entry++, probe++) {
2399 /*
2400  * GROT: Add code to remove incomplete entries.
2401  */
2402 		/*
2403 		 * If we are looking for INCOMPLETE entries, show only those.
2404 		 * If we are looking for complete entries, show only those.
2405 		 */
2406 		if ((args->flags & XFS_ATTR_INCOMPLETE) !=
2407 		    (entry->flags & XFS_ATTR_INCOMPLETE)) {
2408 			continue;
2409 		}
2410 		if (entry->flags & XFS_ATTR_LOCAL) {
2411 			name_loc = xfs_attr3_leaf_name_local(leaf, probe);
2412 			if (name_loc->namelen != args->namelen)
2413 				continue;
2414 			if (memcmp(args->name, name_loc->nameval,
2415 							args->namelen) != 0)
2416 				continue;
2417 			if (!xfs_attr_namesp_match(args->flags, entry->flags))
2418 				continue;
2419 			args->index = probe;
2420 			return -EEXIST;
2421 		} else {
2422 			name_rmt = xfs_attr3_leaf_name_remote(leaf, probe);
2423 			if (name_rmt->namelen != args->namelen)
2424 				continue;
2425 			if (memcmp(args->name, name_rmt->name,
2426 							args->namelen) != 0)
2427 				continue;
2428 			if (!xfs_attr_namesp_match(args->flags, entry->flags))
2429 				continue;
2430 			args->index = probe;
2431 			args->rmtvaluelen = be32_to_cpu(name_rmt->valuelen);
2432 			args->rmtblkno = be32_to_cpu(name_rmt->valueblk);
2433 			args->rmtblkcnt = xfs_attr3_rmt_blocks(
2434 							args->dp->i_mount,
2435 							args->rmtvaluelen);
2436 			return -EEXIST;
2437 		}
2438 	}
2439 	args->index = probe;
2440 	return -ENOATTR;
2441 }
2442 
2443 /*
2444  * Get the value associated with an attribute name from a leaf attribute
2445  * list structure.
2446  *
2447  * If ATTR_KERNOVAL is specified, only the length needs to be returned.
2448  * Unlike a lookup, we only return an error if the attribute does not
2449  * exist or we can't retrieve the value.
2450  */
2451 int
2452 xfs_attr3_leaf_getvalue(
2453 	struct xfs_buf		*bp,
2454 	struct xfs_da_args	*args)
2455 {
2456 	struct xfs_attr_leafblock *leaf;
2457 	struct xfs_attr3_icleaf_hdr ichdr;
2458 	struct xfs_attr_leaf_entry *entry;
2459 	struct xfs_attr_leaf_name_local *name_loc;
2460 	struct xfs_attr_leaf_name_remote *name_rmt;
2461 
2462 	leaf = bp->b_addr;
2463 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
2464 	ASSERT(ichdr.count < args->geo->blksize / 8);
2465 	ASSERT(args->index < ichdr.count);
2466 
2467 	entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
2468 	if (entry->flags & XFS_ATTR_LOCAL) {
2469 		name_loc = xfs_attr3_leaf_name_local(leaf, args->index);
2470 		ASSERT(name_loc->namelen == args->namelen);
2471 		ASSERT(memcmp(args->name, name_loc->nameval, args->namelen) == 0);
2472 		return xfs_attr_copy_value(args,
2473 					&name_loc->nameval[args->namelen],
2474 					be16_to_cpu(name_loc->valuelen));
2475 	}
2476 
2477 	name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
2478 	ASSERT(name_rmt->namelen == args->namelen);
2479 	ASSERT(memcmp(args->name, name_rmt->name, args->namelen) == 0);
2480 	args->rmtvaluelen = be32_to_cpu(name_rmt->valuelen);
2481 	args->rmtblkno = be32_to_cpu(name_rmt->valueblk);
2482 	args->rmtblkcnt = xfs_attr3_rmt_blocks(args->dp->i_mount,
2483 					       args->rmtvaluelen);
2484 	return xfs_attr_copy_value(args, NULL, args->rmtvaluelen);
2485 }
2486 
2487 /*========================================================================
2488  * Utility routines.
2489  *========================================================================*/
2490 
2491 /*
2492  * Move the indicated entries from one leaf to another.
2493  * NOTE: this routine modifies both source and destination leaves.
2494  */
2495 /*ARGSUSED*/
2496 STATIC void
2497 xfs_attr3_leaf_moveents(
2498 	struct xfs_da_args		*args,
2499 	struct xfs_attr_leafblock	*leaf_s,
2500 	struct xfs_attr3_icleaf_hdr	*ichdr_s,
2501 	int				start_s,
2502 	struct xfs_attr_leafblock	*leaf_d,
2503 	struct xfs_attr3_icleaf_hdr	*ichdr_d,
2504 	int				start_d,
2505 	int				count)
2506 {
2507 	struct xfs_attr_leaf_entry	*entry_s;
2508 	struct xfs_attr_leaf_entry	*entry_d;
2509 	int				desti;
2510 	int				tmp;
2511 	int				i;
2512 
2513 	/*
2514 	 * Check for nothing to do.
2515 	 */
2516 	if (count == 0)
2517 		return;
2518 
2519 	/*
2520 	 * Set up environment.
2521 	 */
2522 	ASSERT(ichdr_s->magic == XFS_ATTR_LEAF_MAGIC ||
2523 	       ichdr_s->magic == XFS_ATTR3_LEAF_MAGIC);
2524 	ASSERT(ichdr_s->magic == ichdr_d->magic);
2525 	ASSERT(ichdr_s->count > 0 && ichdr_s->count < args->geo->blksize / 8);
2526 	ASSERT(ichdr_s->firstused >= (ichdr_s->count * sizeof(*entry_s))
2527 					+ xfs_attr3_leaf_hdr_size(leaf_s));
2528 	ASSERT(ichdr_d->count < args->geo->blksize / 8);
2529 	ASSERT(ichdr_d->firstused >= (ichdr_d->count * sizeof(*entry_d))
2530 					+ xfs_attr3_leaf_hdr_size(leaf_d));
2531 
2532 	ASSERT(start_s < ichdr_s->count);
2533 	ASSERT(start_d <= ichdr_d->count);
2534 	ASSERT(count <= ichdr_s->count);
2535 
2536 
2537 	/*
2538 	 * Move the entries in the destination leaf up to make a hole?
2539 	 */
2540 	if (start_d < ichdr_d->count) {
2541 		tmp  = ichdr_d->count - start_d;
2542 		tmp *= sizeof(xfs_attr_leaf_entry_t);
2543 		entry_s = &xfs_attr3_leaf_entryp(leaf_d)[start_d];
2544 		entry_d = &xfs_attr3_leaf_entryp(leaf_d)[start_d + count];
2545 		memmove(entry_d, entry_s, tmp);
2546 	}
2547 
2548 	/*
2549 	 * Copy all entry's in the same (sorted) order,
2550 	 * but allocate attribute info packed and in sequence.
2551 	 */
2552 	entry_s = &xfs_attr3_leaf_entryp(leaf_s)[start_s];
2553 	entry_d = &xfs_attr3_leaf_entryp(leaf_d)[start_d];
2554 	desti = start_d;
2555 	for (i = 0; i < count; entry_s++, entry_d++, desti++, i++) {
2556 		ASSERT(be16_to_cpu(entry_s->nameidx) >= ichdr_s->firstused);
2557 		tmp = xfs_attr_leaf_entsize(leaf_s, start_s + i);
2558 #ifdef GROT
2559 		/*
2560 		 * Code to drop INCOMPLETE entries.  Difficult to use as we
2561 		 * may also need to change the insertion index.  Code turned
2562 		 * off for 6.2, should be revisited later.
2563 		 */
2564 		if (entry_s->flags & XFS_ATTR_INCOMPLETE) { /* skip partials? */
2565 			memset(xfs_attr3_leaf_name(leaf_s, start_s + i), 0, tmp);
2566 			ichdr_s->usedbytes -= tmp;
2567 			ichdr_s->count -= 1;
2568 			entry_d--;	/* to compensate for ++ in loop hdr */
2569 			desti--;
2570 			if ((start_s + i) < offset)
2571 				result++;	/* insertion index adjustment */
2572 		} else {
2573 #endif /* GROT */
2574 			ichdr_d->firstused -= tmp;
2575 			/* both on-disk, don't endian flip twice */
2576 			entry_d->hashval = entry_s->hashval;
2577 			entry_d->nameidx = cpu_to_be16(ichdr_d->firstused);
2578 			entry_d->flags = entry_s->flags;
2579 			ASSERT(be16_to_cpu(entry_d->nameidx) + tmp
2580 							<= args->geo->blksize);
2581 			memmove(xfs_attr3_leaf_name(leaf_d, desti),
2582 				xfs_attr3_leaf_name(leaf_s, start_s + i), tmp);
2583 			ASSERT(be16_to_cpu(entry_s->nameidx) + tmp
2584 							<= args->geo->blksize);
2585 			memset(xfs_attr3_leaf_name(leaf_s, start_s + i), 0, tmp);
2586 			ichdr_s->usedbytes -= tmp;
2587 			ichdr_d->usedbytes += tmp;
2588 			ichdr_s->count -= 1;
2589 			ichdr_d->count += 1;
2590 			tmp = ichdr_d->count * sizeof(xfs_attr_leaf_entry_t)
2591 					+ xfs_attr3_leaf_hdr_size(leaf_d);
2592 			ASSERT(ichdr_d->firstused >= tmp);
2593 #ifdef GROT
2594 		}
2595 #endif /* GROT */
2596 	}
2597 
2598 	/*
2599 	 * Zero out the entries we just copied.
2600 	 */
2601 	if (start_s == ichdr_s->count) {
2602 		tmp = count * sizeof(xfs_attr_leaf_entry_t);
2603 		entry_s = &xfs_attr3_leaf_entryp(leaf_s)[start_s];
2604 		ASSERT(((char *)entry_s + tmp) <=
2605 		       ((char *)leaf_s + args->geo->blksize));
2606 		memset(entry_s, 0, tmp);
2607 	} else {
2608 		/*
2609 		 * Move the remaining entries down to fill the hole,
2610 		 * then zero the entries at the top.
2611 		 */
2612 		tmp  = (ichdr_s->count - count) * sizeof(xfs_attr_leaf_entry_t);
2613 		entry_s = &xfs_attr3_leaf_entryp(leaf_s)[start_s + count];
2614 		entry_d = &xfs_attr3_leaf_entryp(leaf_s)[start_s];
2615 		memmove(entry_d, entry_s, tmp);
2616 
2617 		tmp = count * sizeof(xfs_attr_leaf_entry_t);
2618 		entry_s = &xfs_attr3_leaf_entryp(leaf_s)[ichdr_s->count];
2619 		ASSERT(((char *)entry_s + tmp) <=
2620 		       ((char *)leaf_s + args->geo->blksize));
2621 		memset(entry_s, 0, tmp);
2622 	}
2623 
2624 	/*
2625 	 * Fill in the freemap information
2626 	 */
2627 	ichdr_d->freemap[0].base = xfs_attr3_leaf_hdr_size(leaf_d);
2628 	ichdr_d->freemap[0].base += ichdr_d->count * sizeof(xfs_attr_leaf_entry_t);
2629 	ichdr_d->freemap[0].size = ichdr_d->firstused - ichdr_d->freemap[0].base;
2630 	ichdr_d->freemap[1].base = 0;
2631 	ichdr_d->freemap[2].base = 0;
2632 	ichdr_d->freemap[1].size = 0;
2633 	ichdr_d->freemap[2].size = 0;
2634 	ichdr_s->holes = 1;	/* leaf may not be compact */
2635 }
2636 
2637 /*
2638  * Pick up the last hashvalue from a leaf block.
2639  */
2640 xfs_dahash_t
2641 xfs_attr_leaf_lasthash(
2642 	struct xfs_buf	*bp,
2643 	int		*count)
2644 {
2645 	struct xfs_attr3_icleaf_hdr ichdr;
2646 	struct xfs_attr_leaf_entry *entries;
2647 	struct xfs_mount *mp = bp->b_mount;
2648 
2649 	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, bp->b_addr);
2650 	entries = xfs_attr3_leaf_entryp(bp->b_addr);
2651 	if (count)
2652 		*count = ichdr.count;
2653 	if (!ichdr.count)
2654 		return 0;
2655 	return be32_to_cpu(entries[ichdr.count - 1].hashval);
2656 }
2657 
2658 /*
2659  * Calculate the number of bytes used to store the indicated attribute
2660  * (whether local or remote only calculate bytes in this block).
2661  */
2662 STATIC int
2663 xfs_attr_leaf_entsize(xfs_attr_leafblock_t *leaf, int index)
2664 {
2665 	struct xfs_attr_leaf_entry *entries;
2666 	xfs_attr_leaf_name_local_t *name_loc;
2667 	xfs_attr_leaf_name_remote_t *name_rmt;
2668 	int size;
2669 
2670 	entries = xfs_attr3_leaf_entryp(leaf);
2671 	if (entries[index].flags & XFS_ATTR_LOCAL) {
2672 		name_loc = xfs_attr3_leaf_name_local(leaf, index);
2673 		size = xfs_attr_leaf_entsize_local(name_loc->namelen,
2674 						   be16_to_cpu(name_loc->valuelen));
2675 	} else {
2676 		name_rmt = xfs_attr3_leaf_name_remote(leaf, index);
2677 		size = xfs_attr_leaf_entsize_remote(name_rmt->namelen);
2678 	}
2679 	return size;
2680 }
2681 
2682 /*
2683  * Calculate the number of bytes that would be required to store the new
2684  * attribute (whether local or remote only calculate bytes in this block).
2685  * This routine decides as a side effect whether the attribute will be
2686  * a "local" or a "remote" attribute.
2687  */
2688 int
2689 xfs_attr_leaf_newentsize(
2690 	struct xfs_da_args	*args,
2691 	int			*local)
2692 {
2693 	int			size;
2694 
2695 	size = xfs_attr_leaf_entsize_local(args->namelen, args->valuelen);
2696 	if (size < xfs_attr_leaf_entsize_local_max(args->geo->blksize)) {
2697 		if (local)
2698 			*local = 1;
2699 		return size;
2700 	}
2701 	if (local)
2702 		*local = 0;
2703 	return xfs_attr_leaf_entsize_remote(args->namelen);
2704 }
2705 
2706 
2707 /*========================================================================
2708  * Manage the INCOMPLETE flag in a leaf entry
2709  *========================================================================*/
2710 
2711 /*
2712  * Clear the INCOMPLETE flag on an entry in a leaf block.
2713  */
2714 int
2715 xfs_attr3_leaf_clearflag(
2716 	struct xfs_da_args	*args)
2717 {
2718 	struct xfs_attr_leafblock *leaf;
2719 	struct xfs_attr_leaf_entry *entry;
2720 	struct xfs_attr_leaf_name_remote *name_rmt;
2721 	struct xfs_buf		*bp;
2722 	int			error;
2723 #ifdef DEBUG
2724 	struct xfs_attr3_icleaf_hdr ichdr;
2725 	xfs_attr_leaf_name_local_t *name_loc;
2726 	int namelen;
2727 	char *name;
2728 #endif /* DEBUG */
2729 
2730 	trace_xfs_attr_leaf_clearflag(args);
2731 	/*
2732 	 * Set up the operation.
2733 	 */
2734 	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, &bp);
2735 	if (error)
2736 		return error;
2737 
2738 	leaf = bp->b_addr;
2739 	entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
2740 	ASSERT(entry->flags & XFS_ATTR_INCOMPLETE);
2741 
2742 #ifdef DEBUG
2743 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
2744 	ASSERT(args->index < ichdr.count);
2745 	ASSERT(args->index >= 0);
2746 
2747 	if (entry->flags & XFS_ATTR_LOCAL) {
2748 		name_loc = xfs_attr3_leaf_name_local(leaf, args->index);
2749 		namelen = name_loc->namelen;
2750 		name = (char *)name_loc->nameval;
2751 	} else {
2752 		name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
2753 		namelen = name_rmt->namelen;
2754 		name = (char *)name_rmt->name;
2755 	}
2756 	ASSERT(be32_to_cpu(entry->hashval) == args->hashval);
2757 	ASSERT(namelen == args->namelen);
2758 	ASSERT(memcmp(name, args->name, namelen) == 0);
2759 #endif /* DEBUG */
2760 
2761 	entry->flags &= ~XFS_ATTR_INCOMPLETE;
2762 	xfs_trans_log_buf(args->trans, bp,
2763 			 XFS_DA_LOGRANGE(leaf, entry, sizeof(*entry)));
2764 
2765 	if (args->rmtblkno) {
2766 		ASSERT((entry->flags & XFS_ATTR_LOCAL) == 0);
2767 		name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
2768 		name_rmt->valueblk = cpu_to_be32(args->rmtblkno);
2769 		name_rmt->valuelen = cpu_to_be32(args->rmtvaluelen);
2770 		xfs_trans_log_buf(args->trans, bp,
2771 			 XFS_DA_LOGRANGE(leaf, name_rmt, sizeof(*name_rmt)));
2772 	}
2773 
2774 	/*
2775 	 * Commit the flag value change and start the next trans in series.
2776 	 */
2777 	return xfs_trans_roll_inode(&args->trans, args->dp);
2778 }
2779 
2780 /*
2781  * Set the INCOMPLETE flag on an entry in a leaf block.
2782  */
2783 int
2784 xfs_attr3_leaf_setflag(
2785 	struct xfs_da_args	*args)
2786 {
2787 	struct xfs_attr_leafblock *leaf;
2788 	struct xfs_attr_leaf_entry *entry;
2789 	struct xfs_attr_leaf_name_remote *name_rmt;
2790 	struct xfs_buf		*bp;
2791 	int error;
2792 #ifdef DEBUG
2793 	struct xfs_attr3_icleaf_hdr ichdr;
2794 #endif
2795 
2796 	trace_xfs_attr_leaf_setflag(args);
2797 
2798 	/*
2799 	 * Set up the operation.
2800 	 */
2801 	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, &bp);
2802 	if (error)
2803 		return error;
2804 
2805 	leaf = bp->b_addr;
2806 #ifdef DEBUG
2807 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
2808 	ASSERT(args->index < ichdr.count);
2809 	ASSERT(args->index >= 0);
2810 #endif
2811 	entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
2812 
2813 	ASSERT((entry->flags & XFS_ATTR_INCOMPLETE) == 0);
2814 	entry->flags |= XFS_ATTR_INCOMPLETE;
2815 	xfs_trans_log_buf(args->trans, bp,
2816 			XFS_DA_LOGRANGE(leaf, entry, sizeof(*entry)));
2817 	if ((entry->flags & XFS_ATTR_LOCAL) == 0) {
2818 		name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
2819 		name_rmt->valueblk = 0;
2820 		name_rmt->valuelen = 0;
2821 		xfs_trans_log_buf(args->trans, bp,
2822 			 XFS_DA_LOGRANGE(leaf, name_rmt, sizeof(*name_rmt)));
2823 	}
2824 
2825 	/*
2826 	 * Commit the flag value change and start the next trans in series.
2827 	 */
2828 	return xfs_trans_roll_inode(&args->trans, args->dp);
2829 }
2830 
2831 /*
2832  * In a single transaction, clear the INCOMPLETE flag on the leaf entry
2833  * given by args->blkno/index and set the INCOMPLETE flag on the leaf
2834  * entry given by args->blkno2/index2.
2835  *
2836  * Note that they could be in different blocks, or in the same block.
2837  */
2838 int
2839 xfs_attr3_leaf_flipflags(
2840 	struct xfs_da_args	*args)
2841 {
2842 	struct xfs_attr_leafblock *leaf1;
2843 	struct xfs_attr_leafblock *leaf2;
2844 	struct xfs_attr_leaf_entry *entry1;
2845 	struct xfs_attr_leaf_entry *entry2;
2846 	struct xfs_attr_leaf_name_remote *name_rmt;
2847 	struct xfs_buf		*bp1;
2848 	struct xfs_buf		*bp2;
2849 	int error;
2850 #ifdef DEBUG
2851 	struct xfs_attr3_icleaf_hdr ichdr1;
2852 	struct xfs_attr3_icleaf_hdr ichdr2;
2853 	xfs_attr_leaf_name_local_t *name_loc;
2854 	int namelen1, namelen2;
2855 	char *name1, *name2;
2856 #endif /* DEBUG */
2857 
2858 	trace_xfs_attr_leaf_flipflags(args);
2859 
2860 	/*
2861 	 * Read the block containing the "old" attr
2862 	 */
2863 	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, &bp1);
2864 	if (error)
2865 		return error;
2866 
2867 	/*
2868 	 * Read the block containing the "new" attr, if it is different
2869 	 */
2870 	if (args->blkno2 != args->blkno) {
2871 		error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno2,
2872 					   &bp2);
2873 		if (error)
2874 			return error;
2875 	} else {
2876 		bp2 = bp1;
2877 	}
2878 
2879 	leaf1 = bp1->b_addr;
2880 	entry1 = &xfs_attr3_leaf_entryp(leaf1)[args->index];
2881 
2882 	leaf2 = bp2->b_addr;
2883 	entry2 = &xfs_attr3_leaf_entryp(leaf2)[args->index2];
2884 
2885 #ifdef DEBUG
2886 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr1, leaf1);
2887 	ASSERT(args->index < ichdr1.count);
2888 	ASSERT(args->index >= 0);
2889 
2890 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr2, leaf2);
2891 	ASSERT(args->index2 < ichdr2.count);
2892 	ASSERT(args->index2 >= 0);
2893 
2894 	if (entry1->flags & XFS_ATTR_LOCAL) {
2895 		name_loc = xfs_attr3_leaf_name_local(leaf1, args->index);
2896 		namelen1 = name_loc->namelen;
2897 		name1 = (char *)name_loc->nameval;
2898 	} else {
2899 		name_rmt = xfs_attr3_leaf_name_remote(leaf1, args->index);
2900 		namelen1 = name_rmt->namelen;
2901 		name1 = (char *)name_rmt->name;
2902 	}
2903 	if (entry2->flags & XFS_ATTR_LOCAL) {
2904 		name_loc = xfs_attr3_leaf_name_local(leaf2, args->index2);
2905 		namelen2 = name_loc->namelen;
2906 		name2 = (char *)name_loc->nameval;
2907 	} else {
2908 		name_rmt = xfs_attr3_leaf_name_remote(leaf2, args->index2);
2909 		namelen2 = name_rmt->namelen;
2910 		name2 = (char *)name_rmt->name;
2911 	}
2912 	ASSERT(be32_to_cpu(entry1->hashval) == be32_to_cpu(entry2->hashval));
2913 	ASSERT(namelen1 == namelen2);
2914 	ASSERT(memcmp(name1, name2, namelen1) == 0);
2915 #endif /* DEBUG */
2916 
2917 	ASSERT(entry1->flags & XFS_ATTR_INCOMPLETE);
2918 	ASSERT((entry2->flags & XFS_ATTR_INCOMPLETE) == 0);
2919 
2920 	entry1->flags &= ~XFS_ATTR_INCOMPLETE;
2921 	xfs_trans_log_buf(args->trans, bp1,
2922 			  XFS_DA_LOGRANGE(leaf1, entry1, sizeof(*entry1)));
2923 	if (args->rmtblkno) {
2924 		ASSERT((entry1->flags & XFS_ATTR_LOCAL) == 0);
2925 		name_rmt = xfs_attr3_leaf_name_remote(leaf1, args->index);
2926 		name_rmt->valueblk = cpu_to_be32(args->rmtblkno);
2927 		name_rmt->valuelen = cpu_to_be32(args->rmtvaluelen);
2928 		xfs_trans_log_buf(args->trans, bp1,
2929 			 XFS_DA_LOGRANGE(leaf1, name_rmt, sizeof(*name_rmt)));
2930 	}
2931 
2932 	entry2->flags |= XFS_ATTR_INCOMPLETE;
2933 	xfs_trans_log_buf(args->trans, bp2,
2934 			  XFS_DA_LOGRANGE(leaf2, entry2, sizeof(*entry2)));
2935 	if ((entry2->flags & XFS_ATTR_LOCAL) == 0) {
2936 		name_rmt = xfs_attr3_leaf_name_remote(leaf2, args->index2);
2937 		name_rmt->valueblk = 0;
2938 		name_rmt->valuelen = 0;
2939 		xfs_trans_log_buf(args->trans, bp2,
2940 			 XFS_DA_LOGRANGE(leaf2, name_rmt, sizeof(*name_rmt)));
2941 	}
2942 
2943 	/*
2944 	 * Commit the flag value change and start the next trans in series.
2945 	 */
2946 	error = xfs_trans_roll_inode(&args->trans, args->dp);
2947 
2948 	return error;
2949 }
2950