xref: /openbmc/linux/fs/xfs/libxfs/xfs_attr_leaf.c (revision ae213c44)
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_bit.h"
14 #include "xfs_sb.h"
15 #include "xfs_mount.h"
16 #include "xfs_da_format.h"
17 #include "xfs_da_btree.h"
18 #include "xfs_inode.h"
19 #include "xfs_trans.h"
20 #include "xfs_inode_item.h"
21 #include "xfs_bmap_btree.h"
22 #include "xfs_bmap.h"
23 #include "xfs_attr_sf.h"
24 #include "xfs_attr_remote.h"
25 #include "xfs_attr.h"
26 #include "xfs_attr_leaf.h"
27 #include "xfs_error.h"
28 #include "xfs_trace.h"
29 #include "xfs_buf_item.h"
30 #include "xfs_cksum.h"
31 #include "xfs_dir2.h"
32 #include "xfs_log.h"
33 
34 
35 /*
36  * xfs_attr_leaf.c
37  *
38  * Routines to implement leaf blocks of attributes as Btrees of hashed names.
39  */
40 
41 /*========================================================================
42  * Function prototypes for the kernel.
43  *========================================================================*/
44 
45 /*
46  * Routines used for growing the Btree.
47  */
48 STATIC int xfs_attr3_leaf_create(struct xfs_da_args *args,
49 				 xfs_dablk_t which_block, struct xfs_buf **bpp);
50 STATIC int xfs_attr3_leaf_add_work(struct xfs_buf *leaf_buffer,
51 				   struct xfs_attr3_icleaf_hdr *ichdr,
52 				   struct xfs_da_args *args, int freemap_index);
53 STATIC void xfs_attr3_leaf_compact(struct xfs_da_args *args,
54 				   struct xfs_attr3_icleaf_hdr *ichdr,
55 				   struct xfs_buf *leaf_buffer);
56 STATIC void xfs_attr3_leaf_rebalance(xfs_da_state_t *state,
57 						   xfs_da_state_blk_t *blk1,
58 						   xfs_da_state_blk_t *blk2);
59 STATIC int xfs_attr3_leaf_figure_balance(xfs_da_state_t *state,
60 			xfs_da_state_blk_t *leaf_blk_1,
61 			struct xfs_attr3_icleaf_hdr *ichdr1,
62 			xfs_da_state_blk_t *leaf_blk_2,
63 			struct xfs_attr3_icleaf_hdr *ichdr2,
64 			int *number_entries_in_blk1,
65 			int *number_usedbytes_in_blk1);
66 
67 /*
68  * Utility routines.
69  */
70 STATIC void xfs_attr3_leaf_moveents(struct xfs_da_args *args,
71 			struct xfs_attr_leafblock *src_leaf,
72 			struct xfs_attr3_icleaf_hdr *src_ichdr, int src_start,
73 			struct xfs_attr_leafblock *dst_leaf,
74 			struct xfs_attr3_icleaf_hdr *dst_ichdr, int dst_start,
75 			int move_count);
76 STATIC int xfs_attr_leaf_entsize(xfs_attr_leafblock_t *leaf, int index);
77 
78 /*
79  * attr3 block 'firstused' conversion helpers.
80  *
81  * firstused refers to the offset of the first used byte of the nameval region
82  * of an attr leaf block. The region starts at the tail of the block and expands
83  * backwards towards the middle. As such, firstused is initialized to the block
84  * size for an empty leaf block and is reduced from there.
85  *
86  * The attr3 block size is pegged to the fsb size and the maximum fsb is 64k.
87  * The in-core firstused field is 32-bit and thus supports the maximum fsb size.
88  * The on-disk field is only 16-bit, however, and overflows at 64k. Since this
89  * only occurs at exactly 64k, we use zero as a magic on-disk value to represent
90  * the attr block size. The following helpers manage the conversion between the
91  * in-core and on-disk formats.
92  */
93 
94 static void
95 xfs_attr3_leaf_firstused_from_disk(
96 	struct xfs_da_geometry		*geo,
97 	struct xfs_attr3_icleaf_hdr	*to,
98 	struct xfs_attr_leafblock	*from)
99 {
100 	struct xfs_attr3_leaf_hdr	*hdr3;
101 
102 	if (from->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC)) {
103 		hdr3 = (struct xfs_attr3_leaf_hdr *) from;
104 		to->firstused = be16_to_cpu(hdr3->firstused);
105 	} else {
106 		to->firstused = be16_to_cpu(from->hdr.firstused);
107 	}
108 
109 	/*
110 	 * Convert from the magic fsb size value to actual blocksize. This
111 	 * should only occur for empty blocks when the block size overflows
112 	 * 16-bits.
113 	 */
114 	if (to->firstused == XFS_ATTR3_LEAF_NULLOFF) {
115 		ASSERT(!to->count && !to->usedbytes);
116 		ASSERT(geo->blksize > USHRT_MAX);
117 		to->firstused = geo->blksize;
118 	}
119 }
120 
121 static void
122 xfs_attr3_leaf_firstused_to_disk(
123 	struct xfs_da_geometry		*geo,
124 	struct xfs_attr_leafblock	*to,
125 	struct xfs_attr3_icleaf_hdr	*from)
126 {
127 	struct xfs_attr3_leaf_hdr	*hdr3;
128 	uint32_t			firstused;
129 
130 	/* magic value should only be seen on disk */
131 	ASSERT(from->firstused != XFS_ATTR3_LEAF_NULLOFF);
132 
133 	/*
134 	 * Scale down the 32-bit in-core firstused value to the 16-bit on-disk
135 	 * value. This only overflows at the max supported value of 64k. Use the
136 	 * magic on-disk value to represent block size in this case.
137 	 */
138 	firstused = from->firstused;
139 	if (firstused > USHRT_MAX) {
140 		ASSERT(from->firstused == geo->blksize);
141 		firstused = XFS_ATTR3_LEAF_NULLOFF;
142 	}
143 
144 	if (from->magic == XFS_ATTR3_LEAF_MAGIC) {
145 		hdr3 = (struct xfs_attr3_leaf_hdr *) to;
146 		hdr3->firstused = cpu_to_be16(firstused);
147 	} else {
148 		to->hdr.firstused = cpu_to_be16(firstused);
149 	}
150 }
151 
152 void
153 xfs_attr3_leaf_hdr_from_disk(
154 	struct xfs_da_geometry		*geo,
155 	struct xfs_attr3_icleaf_hdr	*to,
156 	struct xfs_attr_leafblock	*from)
157 {
158 	int	i;
159 
160 	ASSERT(from->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC) ||
161 	       from->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC));
162 
163 	if (from->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC)) {
164 		struct xfs_attr3_leaf_hdr *hdr3 = (struct xfs_attr3_leaf_hdr *)from;
165 
166 		to->forw = be32_to_cpu(hdr3->info.hdr.forw);
167 		to->back = be32_to_cpu(hdr3->info.hdr.back);
168 		to->magic = be16_to_cpu(hdr3->info.hdr.magic);
169 		to->count = be16_to_cpu(hdr3->count);
170 		to->usedbytes = be16_to_cpu(hdr3->usedbytes);
171 		xfs_attr3_leaf_firstused_from_disk(geo, to, from);
172 		to->holes = hdr3->holes;
173 
174 		for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
175 			to->freemap[i].base = be16_to_cpu(hdr3->freemap[i].base);
176 			to->freemap[i].size = be16_to_cpu(hdr3->freemap[i].size);
177 		}
178 		return;
179 	}
180 	to->forw = be32_to_cpu(from->hdr.info.forw);
181 	to->back = be32_to_cpu(from->hdr.info.back);
182 	to->magic = be16_to_cpu(from->hdr.info.magic);
183 	to->count = be16_to_cpu(from->hdr.count);
184 	to->usedbytes = be16_to_cpu(from->hdr.usedbytes);
185 	xfs_attr3_leaf_firstused_from_disk(geo, to, from);
186 	to->holes = from->hdr.holes;
187 
188 	for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
189 		to->freemap[i].base = be16_to_cpu(from->hdr.freemap[i].base);
190 		to->freemap[i].size = be16_to_cpu(from->hdr.freemap[i].size);
191 	}
192 }
193 
194 void
195 xfs_attr3_leaf_hdr_to_disk(
196 	struct xfs_da_geometry		*geo,
197 	struct xfs_attr_leafblock	*to,
198 	struct xfs_attr3_icleaf_hdr	*from)
199 {
200 	int				i;
201 
202 	ASSERT(from->magic == XFS_ATTR_LEAF_MAGIC ||
203 	       from->magic == XFS_ATTR3_LEAF_MAGIC);
204 
205 	if (from->magic == XFS_ATTR3_LEAF_MAGIC) {
206 		struct xfs_attr3_leaf_hdr *hdr3 = (struct xfs_attr3_leaf_hdr *)to;
207 
208 		hdr3->info.hdr.forw = cpu_to_be32(from->forw);
209 		hdr3->info.hdr.back = cpu_to_be32(from->back);
210 		hdr3->info.hdr.magic = cpu_to_be16(from->magic);
211 		hdr3->count = cpu_to_be16(from->count);
212 		hdr3->usedbytes = cpu_to_be16(from->usedbytes);
213 		xfs_attr3_leaf_firstused_to_disk(geo, to, from);
214 		hdr3->holes = from->holes;
215 		hdr3->pad1 = 0;
216 
217 		for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
218 			hdr3->freemap[i].base = cpu_to_be16(from->freemap[i].base);
219 			hdr3->freemap[i].size = cpu_to_be16(from->freemap[i].size);
220 		}
221 		return;
222 	}
223 	to->hdr.info.forw = cpu_to_be32(from->forw);
224 	to->hdr.info.back = cpu_to_be32(from->back);
225 	to->hdr.info.magic = cpu_to_be16(from->magic);
226 	to->hdr.count = cpu_to_be16(from->count);
227 	to->hdr.usedbytes = cpu_to_be16(from->usedbytes);
228 	xfs_attr3_leaf_firstused_to_disk(geo, to, from);
229 	to->hdr.holes = from->holes;
230 	to->hdr.pad1 = 0;
231 
232 	for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
233 		to->hdr.freemap[i].base = cpu_to_be16(from->freemap[i].base);
234 		to->hdr.freemap[i].size = cpu_to_be16(from->freemap[i].size);
235 	}
236 }
237 
238 static xfs_failaddr_t
239 xfs_attr3_leaf_verify(
240 	struct xfs_buf			*bp)
241 {
242 	struct xfs_attr3_icleaf_hdr	ichdr;
243 	struct xfs_mount		*mp = bp->b_target->bt_mount;
244 	struct xfs_attr_leafblock	*leaf = bp->b_addr;
245 	struct xfs_attr_leaf_entry	*entries;
246 	uint32_t			end;	/* must be 32bit - see below */
247 	int				i;
248 	xfs_failaddr_t			fa;
249 
250 	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf);
251 
252 	fa = xfs_da3_blkinfo_verify(bp, bp->b_addr);
253 	if (fa)
254 		return fa;
255 
256 	/*
257 	 * In recovery there is a transient state where count == 0 is valid
258 	 * because we may have transitioned an empty shortform attr to a leaf
259 	 * if the attr didn't fit in shortform.
260 	 */
261 	if (!xfs_log_in_recovery(mp) && ichdr.count == 0)
262 		return __this_address;
263 
264 	/*
265 	 * firstused is the block offset of the first name info structure.
266 	 * Make sure it doesn't go off the block or crash into the header.
267 	 */
268 	if (ichdr.firstused > mp->m_attr_geo->blksize)
269 		return __this_address;
270 	if (ichdr.firstused < xfs_attr3_leaf_hdr_size(leaf))
271 		return __this_address;
272 
273 	/* Make sure the entries array doesn't crash into the name info. */
274 	entries = xfs_attr3_leaf_entryp(bp->b_addr);
275 	if ((char *)&entries[ichdr.count] >
276 	    (char *)bp->b_addr + ichdr.firstused)
277 		return __this_address;
278 
279 	/* XXX: need to range check rest of attr header values */
280 	/* XXX: hash order check? */
281 
282 	/*
283 	 * Quickly check the freemap information.  Attribute data has to be
284 	 * aligned to 4-byte boundaries, and likewise for the free space.
285 	 *
286 	 * Note that for 64k block size filesystems, the freemap entries cannot
287 	 * overflow as they are only be16 fields. However, when checking end
288 	 * pointer of the freemap, we have to be careful to detect overflows and
289 	 * so use uint32_t for those checks.
290 	 */
291 	for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
292 		if (ichdr.freemap[i].base > mp->m_attr_geo->blksize)
293 			return __this_address;
294 		if (ichdr.freemap[i].base & 0x3)
295 			return __this_address;
296 		if (ichdr.freemap[i].size > mp->m_attr_geo->blksize)
297 			return __this_address;
298 		if (ichdr.freemap[i].size & 0x3)
299 			return __this_address;
300 
301 		/* be care of 16 bit overflows here */
302 		end = (uint32_t)ichdr.freemap[i].base + ichdr.freemap[i].size;
303 		if (end < ichdr.freemap[i].base)
304 			return __this_address;
305 		if (end > mp->m_attr_geo->blksize)
306 			return __this_address;
307 	}
308 
309 	return NULL;
310 }
311 
312 static void
313 xfs_attr3_leaf_write_verify(
314 	struct xfs_buf	*bp)
315 {
316 	struct xfs_mount	*mp = bp->b_target->bt_mount;
317 	struct xfs_buf_log_item	*bip = bp->b_log_item;
318 	struct xfs_attr3_leaf_hdr *hdr3 = bp->b_addr;
319 	xfs_failaddr_t		fa;
320 
321 	fa = xfs_attr3_leaf_verify(bp);
322 	if (fa) {
323 		xfs_verifier_error(bp, -EFSCORRUPTED, fa);
324 		return;
325 	}
326 
327 	if (!xfs_sb_version_hascrc(&mp->m_sb))
328 		return;
329 
330 	if (bip)
331 		hdr3->info.lsn = cpu_to_be64(bip->bli_item.li_lsn);
332 
333 	xfs_buf_update_cksum(bp, XFS_ATTR3_LEAF_CRC_OFF);
334 }
335 
336 /*
337  * leaf/node format detection on trees is sketchy, so a node read can be done on
338  * leaf level blocks when detection identifies the tree as a node format tree
339  * incorrectly. In this case, we need to swap the verifier to match the correct
340  * format of the block being read.
341  */
342 static void
343 xfs_attr3_leaf_read_verify(
344 	struct xfs_buf		*bp)
345 {
346 	struct xfs_mount	*mp = bp->b_target->bt_mount;
347 	xfs_failaddr_t		fa;
348 
349 	if (xfs_sb_version_hascrc(&mp->m_sb) &&
350 	     !xfs_buf_verify_cksum(bp, XFS_ATTR3_LEAF_CRC_OFF))
351 		xfs_verifier_error(bp, -EFSBADCRC, __this_address);
352 	else {
353 		fa = xfs_attr3_leaf_verify(bp);
354 		if (fa)
355 			xfs_verifier_error(bp, -EFSCORRUPTED, fa);
356 	}
357 }
358 
359 const struct xfs_buf_ops xfs_attr3_leaf_buf_ops = {
360 	.name = "xfs_attr3_leaf",
361 	.magic16 = { cpu_to_be16(XFS_ATTR_LEAF_MAGIC),
362 		     cpu_to_be16(XFS_ATTR3_LEAF_MAGIC) },
363 	.verify_read = xfs_attr3_leaf_read_verify,
364 	.verify_write = xfs_attr3_leaf_write_verify,
365 	.verify_struct = xfs_attr3_leaf_verify,
366 };
367 
368 int
369 xfs_attr3_leaf_read(
370 	struct xfs_trans	*tp,
371 	struct xfs_inode	*dp,
372 	xfs_dablk_t		bno,
373 	xfs_daddr_t		mappedbno,
374 	struct xfs_buf		**bpp)
375 {
376 	int			err;
377 
378 	err = xfs_da_read_buf(tp, dp, bno, mappedbno, bpp,
379 				XFS_ATTR_FORK, &xfs_attr3_leaf_buf_ops);
380 	if (!err && tp && *bpp)
381 		xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_ATTR_LEAF_BUF);
382 	return err;
383 }
384 
385 /*========================================================================
386  * Namespace helper routines
387  *========================================================================*/
388 
389 /*
390  * If namespace bits don't match return 0.
391  * If all match then return 1.
392  */
393 STATIC int
394 xfs_attr_namesp_match(int arg_flags, int ondisk_flags)
395 {
396 	return XFS_ATTR_NSP_ONDISK(ondisk_flags) == XFS_ATTR_NSP_ARGS_TO_ONDISK(arg_flags);
397 }
398 
399 
400 /*========================================================================
401  * External routines when attribute fork size < XFS_LITINO(mp).
402  *========================================================================*/
403 
404 /*
405  * Query whether the requested number of additional bytes of extended
406  * attribute space will be able to fit inline.
407  *
408  * Returns zero if not, else the di_forkoff fork offset to be used in the
409  * literal area for attribute data once the new bytes have been added.
410  *
411  * di_forkoff must be 8 byte aligned, hence is stored as a >>3 value;
412  * special case for dev/uuid inodes, they have fixed size data forks.
413  */
414 int
415 xfs_attr_shortform_bytesfit(xfs_inode_t *dp, int bytes)
416 {
417 	int offset;
418 	int minforkoff;	/* lower limit on valid forkoff locations */
419 	int maxforkoff;	/* upper limit on valid forkoff locations */
420 	int dsize;
421 	xfs_mount_t *mp = dp->i_mount;
422 
423 	/* rounded down */
424 	offset = (XFS_LITINO(mp, dp->i_d.di_version) - bytes) >> 3;
425 
426 	if (dp->i_d.di_format == XFS_DINODE_FMT_DEV) {
427 		minforkoff = roundup(sizeof(xfs_dev_t), 8) >> 3;
428 		return (offset >= minforkoff) ? minforkoff : 0;
429 	}
430 
431 	/*
432 	 * If the requested numbers of bytes is smaller or equal to the
433 	 * current attribute fork size we can always proceed.
434 	 *
435 	 * Note that if_bytes in the data fork might actually be larger than
436 	 * the current data fork size is due to delalloc extents. In that
437 	 * case either the extent count will go down when they are converted
438 	 * to real extents, or the delalloc conversion will take care of the
439 	 * literal area rebalancing.
440 	 */
441 	if (bytes <= XFS_IFORK_ASIZE(dp))
442 		return dp->i_d.di_forkoff;
443 
444 	/*
445 	 * For attr2 we can try to move the forkoff if there is space in the
446 	 * literal area, but for the old format we are done if there is no
447 	 * space in the fixed attribute fork.
448 	 */
449 	if (!(mp->m_flags & XFS_MOUNT_ATTR2))
450 		return 0;
451 
452 	dsize = dp->i_df.if_bytes;
453 
454 	switch (dp->i_d.di_format) {
455 	case XFS_DINODE_FMT_EXTENTS:
456 		/*
457 		 * If there is no attr fork and the data fork is extents,
458 		 * determine if creating the default attr fork will result
459 		 * in the extents form migrating to btree. If so, the
460 		 * minimum offset only needs to be the space required for
461 		 * the btree root.
462 		 */
463 		if (!dp->i_d.di_forkoff && dp->i_df.if_bytes >
464 		    xfs_default_attroffset(dp))
465 			dsize = XFS_BMDR_SPACE_CALC(MINDBTPTRS);
466 		break;
467 	case XFS_DINODE_FMT_BTREE:
468 		/*
469 		 * If we have a data btree then keep forkoff if we have one,
470 		 * otherwise we are adding a new attr, so then we set
471 		 * minforkoff to where the btree root can finish so we have
472 		 * plenty of room for attrs
473 		 */
474 		if (dp->i_d.di_forkoff) {
475 			if (offset < dp->i_d.di_forkoff)
476 				return 0;
477 			return dp->i_d.di_forkoff;
478 		}
479 		dsize = XFS_BMAP_BROOT_SPACE(mp, dp->i_df.if_broot);
480 		break;
481 	}
482 
483 	/*
484 	 * A data fork btree root must have space for at least
485 	 * MINDBTPTRS key/ptr pairs if the data fork is small or empty.
486 	 */
487 	minforkoff = max(dsize, XFS_BMDR_SPACE_CALC(MINDBTPTRS));
488 	minforkoff = roundup(minforkoff, 8) >> 3;
489 
490 	/* attr fork btree root can have at least this many key/ptr pairs */
491 	maxforkoff = XFS_LITINO(mp, dp->i_d.di_version) -
492 			XFS_BMDR_SPACE_CALC(MINABTPTRS);
493 	maxforkoff = maxforkoff >> 3;	/* rounded down */
494 
495 	if (offset >= maxforkoff)
496 		return maxforkoff;
497 	if (offset >= minforkoff)
498 		return offset;
499 	return 0;
500 }
501 
502 /*
503  * Switch on the ATTR2 superblock bit (implies also FEATURES2)
504  */
505 STATIC void
506 xfs_sbversion_add_attr2(xfs_mount_t *mp, xfs_trans_t *tp)
507 {
508 	if ((mp->m_flags & XFS_MOUNT_ATTR2) &&
509 	    !(xfs_sb_version_hasattr2(&mp->m_sb))) {
510 		spin_lock(&mp->m_sb_lock);
511 		if (!xfs_sb_version_hasattr2(&mp->m_sb)) {
512 			xfs_sb_version_addattr2(&mp->m_sb);
513 			spin_unlock(&mp->m_sb_lock);
514 			xfs_log_sb(tp);
515 		} else
516 			spin_unlock(&mp->m_sb_lock);
517 	}
518 }
519 
520 /*
521  * Create the initial contents of a shortform attribute list.
522  */
523 void
524 xfs_attr_shortform_create(xfs_da_args_t *args)
525 {
526 	xfs_attr_sf_hdr_t *hdr;
527 	xfs_inode_t *dp;
528 	struct xfs_ifork *ifp;
529 
530 	trace_xfs_attr_sf_create(args);
531 
532 	dp = args->dp;
533 	ASSERT(dp != NULL);
534 	ifp = dp->i_afp;
535 	ASSERT(ifp != NULL);
536 	ASSERT(ifp->if_bytes == 0);
537 	if (dp->i_d.di_aformat == XFS_DINODE_FMT_EXTENTS) {
538 		ifp->if_flags &= ~XFS_IFEXTENTS;	/* just in case */
539 		dp->i_d.di_aformat = XFS_DINODE_FMT_LOCAL;
540 		ifp->if_flags |= XFS_IFINLINE;
541 	} else {
542 		ASSERT(ifp->if_flags & XFS_IFINLINE);
543 	}
544 	xfs_idata_realloc(dp, sizeof(*hdr), XFS_ATTR_FORK);
545 	hdr = (xfs_attr_sf_hdr_t *)ifp->if_u1.if_data;
546 	hdr->count = 0;
547 	hdr->totsize = cpu_to_be16(sizeof(*hdr));
548 	xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE | XFS_ILOG_ADATA);
549 }
550 
551 /*
552  * Add a name/value pair to the shortform attribute list.
553  * Overflow from the inode has already been checked for.
554  */
555 void
556 xfs_attr_shortform_add(xfs_da_args_t *args, int forkoff)
557 {
558 	xfs_attr_shortform_t *sf;
559 	xfs_attr_sf_entry_t *sfe;
560 	int i, offset, size;
561 	xfs_mount_t *mp;
562 	xfs_inode_t *dp;
563 	struct xfs_ifork *ifp;
564 
565 	trace_xfs_attr_sf_add(args);
566 
567 	dp = args->dp;
568 	mp = dp->i_mount;
569 	dp->i_d.di_forkoff = forkoff;
570 
571 	ifp = dp->i_afp;
572 	ASSERT(ifp->if_flags & XFS_IFINLINE);
573 	sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
574 	sfe = &sf->list[0];
575 	for (i = 0; i < sf->hdr.count; sfe = XFS_ATTR_SF_NEXTENTRY(sfe), i++) {
576 #ifdef DEBUG
577 		if (sfe->namelen != args->namelen)
578 			continue;
579 		if (memcmp(args->name, sfe->nameval, args->namelen) != 0)
580 			continue;
581 		if (!xfs_attr_namesp_match(args->flags, sfe->flags))
582 			continue;
583 		ASSERT(0);
584 #endif
585 	}
586 
587 	offset = (char *)sfe - (char *)sf;
588 	size = XFS_ATTR_SF_ENTSIZE_BYNAME(args->namelen, args->valuelen);
589 	xfs_idata_realloc(dp, size, XFS_ATTR_FORK);
590 	sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
591 	sfe = (xfs_attr_sf_entry_t *)((char *)sf + offset);
592 
593 	sfe->namelen = args->namelen;
594 	sfe->valuelen = args->valuelen;
595 	sfe->flags = XFS_ATTR_NSP_ARGS_TO_ONDISK(args->flags);
596 	memcpy(sfe->nameval, args->name, args->namelen);
597 	memcpy(&sfe->nameval[args->namelen], args->value, args->valuelen);
598 	sf->hdr.count++;
599 	be16_add_cpu(&sf->hdr.totsize, size);
600 	xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE | XFS_ILOG_ADATA);
601 
602 	xfs_sbversion_add_attr2(mp, args->trans);
603 }
604 
605 /*
606  * After the last attribute is removed revert to original inode format,
607  * making all literal area available to the data fork once more.
608  */
609 void
610 xfs_attr_fork_remove(
611 	struct xfs_inode	*ip,
612 	struct xfs_trans	*tp)
613 {
614 	xfs_idestroy_fork(ip, XFS_ATTR_FORK);
615 	ip->i_d.di_forkoff = 0;
616 	ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
617 
618 	ASSERT(ip->i_d.di_anextents == 0);
619 	ASSERT(ip->i_afp == NULL);
620 
621 	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
622 }
623 
624 /*
625  * Remove an attribute from the shortform attribute list structure.
626  */
627 int
628 xfs_attr_shortform_remove(xfs_da_args_t *args)
629 {
630 	xfs_attr_shortform_t *sf;
631 	xfs_attr_sf_entry_t *sfe;
632 	int base, size=0, end, totsize, i;
633 	xfs_mount_t *mp;
634 	xfs_inode_t *dp;
635 
636 	trace_xfs_attr_sf_remove(args);
637 
638 	dp = args->dp;
639 	mp = dp->i_mount;
640 	base = sizeof(xfs_attr_sf_hdr_t);
641 	sf = (xfs_attr_shortform_t *)dp->i_afp->if_u1.if_data;
642 	sfe = &sf->list[0];
643 	end = sf->hdr.count;
644 	for (i = 0; i < end; sfe = XFS_ATTR_SF_NEXTENTRY(sfe),
645 					base += size, i++) {
646 		size = XFS_ATTR_SF_ENTSIZE(sfe);
647 		if (sfe->namelen != args->namelen)
648 			continue;
649 		if (memcmp(sfe->nameval, args->name, args->namelen) != 0)
650 			continue;
651 		if (!xfs_attr_namesp_match(args->flags, sfe->flags))
652 			continue;
653 		break;
654 	}
655 	if (i == end)
656 		return -ENOATTR;
657 
658 	/*
659 	 * Fix up the attribute fork data, covering the hole
660 	 */
661 	end = base + size;
662 	totsize = be16_to_cpu(sf->hdr.totsize);
663 	if (end != totsize)
664 		memmove(&((char *)sf)[base], &((char *)sf)[end], totsize - end);
665 	sf->hdr.count--;
666 	be16_add_cpu(&sf->hdr.totsize, -size);
667 
668 	/*
669 	 * Fix up the start offset of the attribute fork
670 	 */
671 	totsize -= size;
672 	if (totsize == sizeof(xfs_attr_sf_hdr_t) &&
673 	    (mp->m_flags & XFS_MOUNT_ATTR2) &&
674 	    (dp->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
675 	    !(args->op_flags & XFS_DA_OP_ADDNAME)) {
676 		xfs_attr_fork_remove(dp, args->trans);
677 	} else {
678 		xfs_idata_realloc(dp, -size, XFS_ATTR_FORK);
679 		dp->i_d.di_forkoff = xfs_attr_shortform_bytesfit(dp, totsize);
680 		ASSERT(dp->i_d.di_forkoff);
681 		ASSERT(totsize > sizeof(xfs_attr_sf_hdr_t) ||
682 				(args->op_flags & XFS_DA_OP_ADDNAME) ||
683 				!(mp->m_flags & XFS_MOUNT_ATTR2) ||
684 				dp->i_d.di_format == XFS_DINODE_FMT_BTREE);
685 		xfs_trans_log_inode(args->trans, dp,
686 					XFS_ILOG_CORE | XFS_ILOG_ADATA);
687 	}
688 
689 	xfs_sbversion_add_attr2(mp, args->trans);
690 
691 	return 0;
692 }
693 
694 /*
695  * Look up a name in a shortform attribute list structure.
696  */
697 /*ARGSUSED*/
698 int
699 xfs_attr_shortform_lookup(xfs_da_args_t *args)
700 {
701 	xfs_attr_shortform_t *sf;
702 	xfs_attr_sf_entry_t *sfe;
703 	int i;
704 	struct xfs_ifork *ifp;
705 
706 	trace_xfs_attr_sf_lookup(args);
707 
708 	ifp = args->dp->i_afp;
709 	ASSERT(ifp->if_flags & XFS_IFINLINE);
710 	sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
711 	sfe = &sf->list[0];
712 	for (i = 0; i < sf->hdr.count;
713 				sfe = XFS_ATTR_SF_NEXTENTRY(sfe), i++) {
714 		if (sfe->namelen != args->namelen)
715 			continue;
716 		if (memcmp(args->name, sfe->nameval, args->namelen) != 0)
717 			continue;
718 		if (!xfs_attr_namesp_match(args->flags, sfe->flags))
719 			continue;
720 		return -EEXIST;
721 	}
722 	return -ENOATTR;
723 }
724 
725 /*
726  * Look up a name in a shortform attribute list structure.
727  */
728 /*ARGSUSED*/
729 int
730 xfs_attr_shortform_getvalue(xfs_da_args_t *args)
731 {
732 	xfs_attr_shortform_t *sf;
733 	xfs_attr_sf_entry_t *sfe;
734 	int i;
735 
736 	ASSERT(args->dp->i_afp->if_flags == XFS_IFINLINE);
737 	sf = (xfs_attr_shortform_t *)args->dp->i_afp->if_u1.if_data;
738 	sfe = &sf->list[0];
739 	for (i = 0; i < sf->hdr.count;
740 				sfe = XFS_ATTR_SF_NEXTENTRY(sfe), i++) {
741 		if (sfe->namelen != args->namelen)
742 			continue;
743 		if (memcmp(args->name, sfe->nameval, args->namelen) != 0)
744 			continue;
745 		if (!xfs_attr_namesp_match(args->flags, sfe->flags))
746 			continue;
747 		if (args->flags & ATTR_KERNOVAL) {
748 			args->valuelen = sfe->valuelen;
749 			return -EEXIST;
750 		}
751 		if (args->valuelen < sfe->valuelen) {
752 			args->valuelen = sfe->valuelen;
753 			return -ERANGE;
754 		}
755 		args->valuelen = sfe->valuelen;
756 		memcpy(args->value, &sfe->nameval[args->namelen],
757 						    args->valuelen);
758 		return -EEXIST;
759 	}
760 	return -ENOATTR;
761 }
762 
763 /*
764  * Convert from using the shortform to the leaf.  On success, return the
765  * buffer so that we can keep it locked until we're totally done with it.
766  */
767 int
768 xfs_attr_shortform_to_leaf(
769 	struct xfs_da_args		*args,
770 	struct xfs_buf			**leaf_bp)
771 {
772 	struct xfs_inode		*dp;
773 	struct xfs_attr_shortform	*sf;
774 	struct xfs_attr_sf_entry	*sfe;
775 	struct xfs_da_args		nargs;
776 	char				*tmpbuffer;
777 	int				error, i, size;
778 	xfs_dablk_t			blkno;
779 	struct xfs_buf			*bp;
780 	struct xfs_ifork		*ifp;
781 
782 	trace_xfs_attr_sf_to_leaf(args);
783 
784 	dp = args->dp;
785 	ifp = dp->i_afp;
786 	sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
787 	size = be16_to_cpu(sf->hdr.totsize);
788 	tmpbuffer = kmem_alloc(size, KM_SLEEP);
789 	ASSERT(tmpbuffer != NULL);
790 	memcpy(tmpbuffer, ifp->if_u1.if_data, size);
791 	sf = (xfs_attr_shortform_t *)tmpbuffer;
792 
793 	xfs_idata_realloc(dp, -size, XFS_ATTR_FORK);
794 	xfs_bmap_local_to_extents_empty(dp, XFS_ATTR_FORK);
795 
796 	bp = NULL;
797 	error = xfs_da_grow_inode(args, &blkno);
798 	if (error) {
799 		/*
800 		 * If we hit an IO error middle of the transaction inside
801 		 * grow_inode(), we may have inconsistent data. Bail out.
802 		 */
803 		if (error == -EIO)
804 			goto out;
805 		xfs_idata_realloc(dp, size, XFS_ATTR_FORK);	/* try to put */
806 		memcpy(ifp->if_u1.if_data, tmpbuffer, size);	/* it back */
807 		goto out;
808 	}
809 
810 	ASSERT(blkno == 0);
811 	error = xfs_attr3_leaf_create(args, blkno, &bp);
812 	if (error) {
813 		/* xfs_attr3_leaf_create may not have instantiated a block */
814 		if (bp && (xfs_da_shrink_inode(args, 0, bp) != 0))
815 			goto out;
816 		xfs_idata_realloc(dp, size, XFS_ATTR_FORK);	/* try to put */
817 		memcpy(ifp->if_u1.if_data, tmpbuffer, size);	/* it back */
818 		goto out;
819 	}
820 
821 	memset((char *)&nargs, 0, sizeof(nargs));
822 	nargs.dp = dp;
823 	nargs.geo = args->geo;
824 	nargs.total = args->total;
825 	nargs.whichfork = XFS_ATTR_FORK;
826 	nargs.trans = args->trans;
827 	nargs.op_flags = XFS_DA_OP_OKNOENT;
828 
829 	sfe = &sf->list[0];
830 	for (i = 0; i < sf->hdr.count; i++) {
831 		nargs.name = sfe->nameval;
832 		nargs.namelen = sfe->namelen;
833 		nargs.value = &sfe->nameval[nargs.namelen];
834 		nargs.valuelen = sfe->valuelen;
835 		nargs.hashval = xfs_da_hashname(sfe->nameval,
836 						sfe->namelen);
837 		nargs.flags = XFS_ATTR_NSP_ONDISK_TO_ARGS(sfe->flags);
838 		error = xfs_attr3_leaf_lookup_int(bp, &nargs); /* set a->index */
839 		ASSERT(error == -ENOATTR);
840 		error = xfs_attr3_leaf_add(bp, &nargs);
841 		ASSERT(error != -ENOSPC);
842 		if (error)
843 			goto out;
844 		sfe = XFS_ATTR_SF_NEXTENTRY(sfe);
845 	}
846 	error = 0;
847 	*leaf_bp = bp;
848 out:
849 	kmem_free(tmpbuffer);
850 	return error;
851 }
852 
853 /*
854  * Check a leaf attribute block to see if all the entries would fit into
855  * a shortform attribute list.
856  */
857 int
858 xfs_attr_shortform_allfit(
859 	struct xfs_buf		*bp,
860 	struct xfs_inode	*dp)
861 {
862 	struct xfs_attr_leafblock *leaf;
863 	struct xfs_attr_leaf_entry *entry;
864 	xfs_attr_leaf_name_local_t *name_loc;
865 	struct xfs_attr3_icleaf_hdr leafhdr;
866 	int			bytes;
867 	int			i;
868 	struct xfs_mount	*mp = bp->b_target->bt_mount;
869 
870 	leaf = bp->b_addr;
871 	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &leafhdr, leaf);
872 	entry = xfs_attr3_leaf_entryp(leaf);
873 
874 	bytes = sizeof(struct xfs_attr_sf_hdr);
875 	for (i = 0; i < leafhdr.count; entry++, i++) {
876 		if (entry->flags & XFS_ATTR_INCOMPLETE)
877 			continue;		/* don't copy partial entries */
878 		if (!(entry->flags & XFS_ATTR_LOCAL))
879 			return 0;
880 		name_loc = xfs_attr3_leaf_name_local(leaf, i);
881 		if (name_loc->namelen >= XFS_ATTR_SF_ENTSIZE_MAX)
882 			return 0;
883 		if (be16_to_cpu(name_loc->valuelen) >= XFS_ATTR_SF_ENTSIZE_MAX)
884 			return 0;
885 		bytes += sizeof(struct xfs_attr_sf_entry) - 1
886 				+ name_loc->namelen
887 				+ be16_to_cpu(name_loc->valuelen);
888 	}
889 	if ((dp->i_mount->m_flags & XFS_MOUNT_ATTR2) &&
890 	    (dp->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
891 	    (bytes == sizeof(struct xfs_attr_sf_hdr)))
892 		return -1;
893 	return xfs_attr_shortform_bytesfit(dp, bytes);
894 }
895 
896 /* Verify the consistency of an inline attribute fork. */
897 xfs_failaddr_t
898 xfs_attr_shortform_verify(
899 	struct xfs_inode		*ip)
900 {
901 	struct xfs_attr_shortform	*sfp;
902 	struct xfs_attr_sf_entry	*sfep;
903 	struct xfs_attr_sf_entry	*next_sfep;
904 	char				*endp;
905 	struct xfs_ifork		*ifp;
906 	int				i;
907 	int				size;
908 
909 	ASSERT(ip->i_d.di_aformat == XFS_DINODE_FMT_LOCAL);
910 	ifp = XFS_IFORK_PTR(ip, XFS_ATTR_FORK);
911 	sfp = (struct xfs_attr_shortform *)ifp->if_u1.if_data;
912 	size = ifp->if_bytes;
913 
914 	/*
915 	 * Give up if the attribute is way too short.
916 	 */
917 	if (size < sizeof(struct xfs_attr_sf_hdr))
918 		return __this_address;
919 
920 	endp = (char *)sfp + size;
921 
922 	/* Check all reported entries */
923 	sfep = &sfp->list[0];
924 	for (i = 0; i < sfp->hdr.count; i++) {
925 		/*
926 		 * struct xfs_attr_sf_entry has a variable length.
927 		 * Check the fixed-offset parts of the structure are
928 		 * within the data buffer.
929 		 */
930 		if (((char *)sfep + sizeof(*sfep)) >= endp)
931 			return __this_address;
932 
933 		/* Don't allow names with known bad length. */
934 		if (sfep->namelen == 0)
935 			return __this_address;
936 
937 		/*
938 		 * Check that the variable-length part of the structure is
939 		 * within the data buffer.  The next entry starts after the
940 		 * name component, so nextentry is an acceptable test.
941 		 */
942 		next_sfep = XFS_ATTR_SF_NEXTENTRY(sfep);
943 		if ((char *)next_sfep > endp)
944 			return __this_address;
945 
946 		/*
947 		 * Check for unknown flags.  Short form doesn't support
948 		 * the incomplete or local bits, so we can use the namespace
949 		 * mask here.
950 		 */
951 		if (sfep->flags & ~XFS_ATTR_NSP_ONDISK_MASK)
952 			return __this_address;
953 
954 		/*
955 		 * Check for invalid namespace combinations.  We only allow
956 		 * one namespace flag per xattr, so we can just count the
957 		 * bits (i.e. hweight) here.
958 		 */
959 		if (hweight8(sfep->flags & XFS_ATTR_NSP_ONDISK_MASK) > 1)
960 			return __this_address;
961 
962 		sfep = next_sfep;
963 	}
964 	if ((void *)sfep != (void *)endp)
965 		return __this_address;
966 
967 	return NULL;
968 }
969 
970 /*
971  * Convert a leaf attribute list to shortform attribute list
972  */
973 int
974 xfs_attr3_leaf_to_shortform(
975 	struct xfs_buf		*bp,
976 	struct xfs_da_args	*args,
977 	int			forkoff)
978 {
979 	struct xfs_attr_leafblock *leaf;
980 	struct xfs_attr3_icleaf_hdr ichdr;
981 	struct xfs_attr_leaf_entry *entry;
982 	struct xfs_attr_leaf_name_local *name_loc;
983 	struct xfs_da_args	nargs;
984 	struct xfs_inode	*dp = args->dp;
985 	char			*tmpbuffer;
986 	int			error;
987 	int			i;
988 
989 	trace_xfs_attr_leaf_to_sf(args);
990 
991 	tmpbuffer = kmem_alloc(args->geo->blksize, KM_SLEEP);
992 	if (!tmpbuffer)
993 		return -ENOMEM;
994 
995 	memcpy(tmpbuffer, bp->b_addr, args->geo->blksize);
996 
997 	leaf = (xfs_attr_leafblock_t *)tmpbuffer;
998 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
999 	entry = xfs_attr3_leaf_entryp(leaf);
1000 
1001 	/* XXX (dgc): buffer is about to be marked stale - why zero it? */
1002 	memset(bp->b_addr, 0, args->geo->blksize);
1003 
1004 	/*
1005 	 * Clean out the prior contents of the attribute list.
1006 	 */
1007 	error = xfs_da_shrink_inode(args, 0, bp);
1008 	if (error)
1009 		goto out;
1010 
1011 	if (forkoff == -1) {
1012 		ASSERT(dp->i_mount->m_flags & XFS_MOUNT_ATTR2);
1013 		ASSERT(dp->i_d.di_format != XFS_DINODE_FMT_BTREE);
1014 		xfs_attr_fork_remove(dp, args->trans);
1015 		goto out;
1016 	}
1017 
1018 	xfs_attr_shortform_create(args);
1019 
1020 	/*
1021 	 * Copy the attributes
1022 	 */
1023 	memset((char *)&nargs, 0, sizeof(nargs));
1024 	nargs.geo = args->geo;
1025 	nargs.dp = dp;
1026 	nargs.total = args->total;
1027 	nargs.whichfork = XFS_ATTR_FORK;
1028 	nargs.trans = args->trans;
1029 	nargs.op_flags = XFS_DA_OP_OKNOENT;
1030 
1031 	for (i = 0; i < ichdr.count; entry++, i++) {
1032 		if (entry->flags & XFS_ATTR_INCOMPLETE)
1033 			continue;	/* don't copy partial entries */
1034 		if (!entry->nameidx)
1035 			continue;
1036 		ASSERT(entry->flags & XFS_ATTR_LOCAL);
1037 		name_loc = xfs_attr3_leaf_name_local(leaf, i);
1038 		nargs.name = name_loc->nameval;
1039 		nargs.namelen = name_loc->namelen;
1040 		nargs.value = &name_loc->nameval[nargs.namelen];
1041 		nargs.valuelen = be16_to_cpu(name_loc->valuelen);
1042 		nargs.hashval = be32_to_cpu(entry->hashval);
1043 		nargs.flags = XFS_ATTR_NSP_ONDISK_TO_ARGS(entry->flags);
1044 		xfs_attr_shortform_add(&nargs, forkoff);
1045 	}
1046 	error = 0;
1047 
1048 out:
1049 	kmem_free(tmpbuffer);
1050 	return error;
1051 }
1052 
1053 /*
1054  * Convert from using a single leaf to a root node and a leaf.
1055  */
1056 int
1057 xfs_attr3_leaf_to_node(
1058 	struct xfs_da_args	*args)
1059 {
1060 	struct xfs_attr_leafblock *leaf;
1061 	struct xfs_attr3_icleaf_hdr icleafhdr;
1062 	struct xfs_attr_leaf_entry *entries;
1063 	struct xfs_da_node_entry *btree;
1064 	struct xfs_da3_icnode_hdr icnodehdr;
1065 	struct xfs_da_intnode	*node;
1066 	struct xfs_inode	*dp = args->dp;
1067 	struct xfs_mount	*mp = dp->i_mount;
1068 	struct xfs_buf		*bp1 = NULL;
1069 	struct xfs_buf		*bp2 = NULL;
1070 	xfs_dablk_t		blkno;
1071 	int			error;
1072 
1073 	trace_xfs_attr_leaf_to_node(args);
1074 
1075 	error = xfs_da_grow_inode(args, &blkno);
1076 	if (error)
1077 		goto out;
1078 	error = xfs_attr3_leaf_read(args->trans, dp, 0, -1, &bp1);
1079 	if (error)
1080 		goto out;
1081 
1082 	error = xfs_da_get_buf(args->trans, dp, blkno, -1, &bp2, XFS_ATTR_FORK);
1083 	if (error)
1084 		goto out;
1085 
1086 	/* copy leaf to new buffer, update identifiers */
1087 	xfs_trans_buf_set_type(args->trans, bp2, XFS_BLFT_ATTR_LEAF_BUF);
1088 	bp2->b_ops = bp1->b_ops;
1089 	memcpy(bp2->b_addr, bp1->b_addr, args->geo->blksize);
1090 	if (xfs_sb_version_hascrc(&mp->m_sb)) {
1091 		struct xfs_da3_blkinfo *hdr3 = bp2->b_addr;
1092 		hdr3->blkno = cpu_to_be64(bp2->b_bn);
1093 	}
1094 	xfs_trans_log_buf(args->trans, bp2, 0, args->geo->blksize - 1);
1095 
1096 	/*
1097 	 * Set up the new root node.
1098 	 */
1099 	error = xfs_da3_node_create(args, 0, 1, &bp1, XFS_ATTR_FORK);
1100 	if (error)
1101 		goto out;
1102 	node = bp1->b_addr;
1103 	dp->d_ops->node_hdr_from_disk(&icnodehdr, node);
1104 	btree = dp->d_ops->node_tree_p(node);
1105 
1106 	leaf = bp2->b_addr;
1107 	xfs_attr3_leaf_hdr_from_disk(args->geo, &icleafhdr, leaf);
1108 	entries = xfs_attr3_leaf_entryp(leaf);
1109 
1110 	/* both on-disk, don't endian-flip twice */
1111 	btree[0].hashval = entries[icleafhdr.count - 1].hashval;
1112 	btree[0].before = cpu_to_be32(blkno);
1113 	icnodehdr.count = 1;
1114 	dp->d_ops->node_hdr_to_disk(node, &icnodehdr);
1115 	xfs_trans_log_buf(args->trans, bp1, 0, args->geo->blksize - 1);
1116 	error = 0;
1117 out:
1118 	return error;
1119 }
1120 
1121 /*========================================================================
1122  * Routines used for growing the Btree.
1123  *========================================================================*/
1124 
1125 /*
1126  * Create the initial contents of a leaf attribute list
1127  * or a leaf in a node attribute list.
1128  */
1129 STATIC int
1130 xfs_attr3_leaf_create(
1131 	struct xfs_da_args	*args,
1132 	xfs_dablk_t		blkno,
1133 	struct xfs_buf		**bpp)
1134 {
1135 	struct xfs_attr_leafblock *leaf;
1136 	struct xfs_attr3_icleaf_hdr ichdr;
1137 	struct xfs_inode	*dp = args->dp;
1138 	struct xfs_mount	*mp = dp->i_mount;
1139 	struct xfs_buf		*bp;
1140 	int			error;
1141 
1142 	trace_xfs_attr_leaf_create(args);
1143 
1144 	error = xfs_da_get_buf(args->trans, args->dp, blkno, -1, &bp,
1145 					    XFS_ATTR_FORK);
1146 	if (error)
1147 		return error;
1148 	bp->b_ops = &xfs_attr3_leaf_buf_ops;
1149 	xfs_trans_buf_set_type(args->trans, bp, XFS_BLFT_ATTR_LEAF_BUF);
1150 	leaf = bp->b_addr;
1151 	memset(leaf, 0, args->geo->blksize);
1152 
1153 	memset(&ichdr, 0, sizeof(ichdr));
1154 	ichdr.firstused = args->geo->blksize;
1155 
1156 	if (xfs_sb_version_hascrc(&mp->m_sb)) {
1157 		struct xfs_da3_blkinfo *hdr3 = bp->b_addr;
1158 
1159 		ichdr.magic = XFS_ATTR3_LEAF_MAGIC;
1160 
1161 		hdr3->blkno = cpu_to_be64(bp->b_bn);
1162 		hdr3->owner = cpu_to_be64(dp->i_ino);
1163 		uuid_copy(&hdr3->uuid, &mp->m_sb.sb_meta_uuid);
1164 
1165 		ichdr.freemap[0].base = sizeof(struct xfs_attr3_leaf_hdr);
1166 	} else {
1167 		ichdr.magic = XFS_ATTR_LEAF_MAGIC;
1168 		ichdr.freemap[0].base = sizeof(struct xfs_attr_leaf_hdr);
1169 	}
1170 	ichdr.freemap[0].size = ichdr.firstused - ichdr.freemap[0].base;
1171 
1172 	xfs_attr3_leaf_hdr_to_disk(args->geo, leaf, &ichdr);
1173 	xfs_trans_log_buf(args->trans, bp, 0, args->geo->blksize - 1);
1174 
1175 	*bpp = bp;
1176 	return 0;
1177 }
1178 
1179 /*
1180  * Split the leaf node, rebalance, then add the new entry.
1181  */
1182 int
1183 xfs_attr3_leaf_split(
1184 	struct xfs_da_state	*state,
1185 	struct xfs_da_state_blk	*oldblk,
1186 	struct xfs_da_state_blk	*newblk)
1187 {
1188 	xfs_dablk_t blkno;
1189 	int error;
1190 
1191 	trace_xfs_attr_leaf_split(state->args);
1192 
1193 	/*
1194 	 * Allocate space for a new leaf node.
1195 	 */
1196 	ASSERT(oldblk->magic == XFS_ATTR_LEAF_MAGIC);
1197 	error = xfs_da_grow_inode(state->args, &blkno);
1198 	if (error)
1199 		return error;
1200 	error = xfs_attr3_leaf_create(state->args, blkno, &newblk->bp);
1201 	if (error)
1202 		return error;
1203 	newblk->blkno = blkno;
1204 	newblk->magic = XFS_ATTR_LEAF_MAGIC;
1205 
1206 	/*
1207 	 * Rebalance the entries across the two leaves.
1208 	 * NOTE: rebalance() currently depends on the 2nd block being empty.
1209 	 */
1210 	xfs_attr3_leaf_rebalance(state, oldblk, newblk);
1211 	error = xfs_da3_blk_link(state, oldblk, newblk);
1212 	if (error)
1213 		return error;
1214 
1215 	/*
1216 	 * Save info on "old" attribute for "atomic rename" ops, leaf_add()
1217 	 * modifies the index/blkno/rmtblk/rmtblkcnt fields to show the
1218 	 * "new" attrs info.  Will need the "old" info to remove it later.
1219 	 *
1220 	 * Insert the "new" entry in the correct block.
1221 	 */
1222 	if (state->inleaf) {
1223 		trace_xfs_attr_leaf_add_old(state->args);
1224 		error = xfs_attr3_leaf_add(oldblk->bp, state->args);
1225 	} else {
1226 		trace_xfs_attr_leaf_add_new(state->args);
1227 		error = xfs_attr3_leaf_add(newblk->bp, state->args);
1228 	}
1229 
1230 	/*
1231 	 * Update last hashval in each block since we added the name.
1232 	 */
1233 	oldblk->hashval = xfs_attr_leaf_lasthash(oldblk->bp, NULL);
1234 	newblk->hashval = xfs_attr_leaf_lasthash(newblk->bp, NULL);
1235 	return error;
1236 }
1237 
1238 /*
1239  * Add a name to the leaf attribute list structure.
1240  */
1241 int
1242 xfs_attr3_leaf_add(
1243 	struct xfs_buf		*bp,
1244 	struct xfs_da_args	*args)
1245 {
1246 	struct xfs_attr_leafblock *leaf;
1247 	struct xfs_attr3_icleaf_hdr ichdr;
1248 	int			tablesize;
1249 	int			entsize;
1250 	int			sum;
1251 	int			tmp;
1252 	int			i;
1253 
1254 	trace_xfs_attr_leaf_add(args);
1255 
1256 	leaf = bp->b_addr;
1257 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
1258 	ASSERT(args->index >= 0 && args->index <= ichdr.count);
1259 	entsize = xfs_attr_leaf_newentsize(args, NULL);
1260 
1261 	/*
1262 	 * Search through freemap for first-fit on new name length.
1263 	 * (may need to figure in size of entry struct too)
1264 	 */
1265 	tablesize = (ichdr.count + 1) * sizeof(xfs_attr_leaf_entry_t)
1266 					+ xfs_attr3_leaf_hdr_size(leaf);
1267 	for (sum = 0, i = XFS_ATTR_LEAF_MAPSIZE - 1; i >= 0; i--) {
1268 		if (tablesize > ichdr.firstused) {
1269 			sum += ichdr.freemap[i].size;
1270 			continue;
1271 		}
1272 		if (!ichdr.freemap[i].size)
1273 			continue;	/* no space in this map */
1274 		tmp = entsize;
1275 		if (ichdr.freemap[i].base < ichdr.firstused)
1276 			tmp += sizeof(xfs_attr_leaf_entry_t);
1277 		if (ichdr.freemap[i].size >= tmp) {
1278 			tmp = xfs_attr3_leaf_add_work(bp, &ichdr, args, i);
1279 			goto out_log_hdr;
1280 		}
1281 		sum += ichdr.freemap[i].size;
1282 	}
1283 
1284 	/*
1285 	 * If there are no holes in the address space of the block,
1286 	 * and we don't have enough freespace, then compaction will do us
1287 	 * no good and we should just give up.
1288 	 */
1289 	if (!ichdr.holes && sum < entsize)
1290 		return -ENOSPC;
1291 
1292 	/*
1293 	 * Compact the entries to coalesce free space.
1294 	 * This may change the hdr->count via dropping INCOMPLETE entries.
1295 	 */
1296 	xfs_attr3_leaf_compact(args, &ichdr, bp);
1297 
1298 	/*
1299 	 * After compaction, the block is guaranteed to have only one
1300 	 * free region, in freemap[0].  If it is not big enough, give up.
1301 	 */
1302 	if (ichdr.freemap[0].size < (entsize + sizeof(xfs_attr_leaf_entry_t))) {
1303 		tmp = -ENOSPC;
1304 		goto out_log_hdr;
1305 	}
1306 
1307 	tmp = xfs_attr3_leaf_add_work(bp, &ichdr, args, 0);
1308 
1309 out_log_hdr:
1310 	xfs_attr3_leaf_hdr_to_disk(args->geo, leaf, &ichdr);
1311 	xfs_trans_log_buf(args->trans, bp,
1312 		XFS_DA_LOGRANGE(leaf, &leaf->hdr,
1313 				xfs_attr3_leaf_hdr_size(leaf)));
1314 	return tmp;
1315 }
1316 
1317 /*
1318  * Add a name to a leaf attribute list structure.
1319  */
1320 STATIC int
1321 xfs_attr3_leaf_add_work(
1322 	struct xfs_buf		*bp,
1323 	struct xfs_attr3_icleaf_hdr *ichdr,
1324 	struct xfs_da_args	*args,
1325 	int			mapindex)
1326 {
1327 	struct xfs_attr_leafblock *leaf;
1328 	struct xfs_attr_leaf_entry *entry;
1329 	struct xfs_attr_leaf_name_local *name_loc;
1330 	struct xfs_attr_leaf_name_remote *name_rmt;
1331 	struct xfs_mount	*mp;
1332 	int			tmp;
1333 	int			i;
1334 
1335 	trace_xfs_attr_leaf_add_work(args);
1336 
1337 	leaf = bp->b_addr;
1338 	ASSERT(mapindex >= 0 && mapindex < XFS_ATTR_LEAF_MAPSIZE);
1339 	ASSERT(args->index >= 0 && args->index <= ichdr->count);
1340 
1341 	/*
1342 	 * Force open some space in the entry array and fill it in.
1343 	 */
1344 	entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
1345 	if (args->index < ichdr->count) {
1346 		tmp  = ichdr->count - args->index;
1347 		tmp *= sizeof(xfs_attr_leaf_entry_t);
1348 		memmove(entry + 1, entry, tmp);
1349 		xfs_trans_log_buf(args->trans, bp,
1350 		    XFS_DA_LOGRANGE(leaf, entry, tmp + sizeof(*entry)));
1351 	}
1352 	ichdr->count++;
1353 
1354 	/*
1355 	 * Allocate space for the new string (at the end of the run).
1356 	 */
1357 	mp = args->trans->t_mountp;
1358 	ASSERT(ichdr->freemap[mapindex].base < args->geo->blksize);
1359 	ASSERT((ichdr->freemap[mapindex].base & 0x3) == 0);
1360 	ASSERT(ichdr->freemap[mapindex].size >=
1361 		xfs_attr_leaf_newentsize(args, NULL));
1362 	ASSERT(ichdr->freemap[mapindex].size < args->geo->blksize);
1363 	ASSERT((ichdr->freemap[mapindex].size & 0x3) == 0);
1364 
1365 	ichdr->freemap[mapindex].size -= xfs_attr_leaf_newentsize(args, &tmp);
1366 
1367 	entry->nameidx = cpu_to_be16(ichdr->freemap[mapindex].base +
1368 				     ichdr->freemap[mapindex].size);
1369 	entry->hashval = cpu_to_be32(args->hashval);
1370 	entry->flags = tmp ? XFS_ATTR_LOCAL : 0;
1371 	entry->flags |= XFS_ATTR_NSP_ARGS_TO_ONDISK(args->flags);
1372 	if (args->op_flags & XFS_DA_OP_RENAME) {
1373 		entry->flags |= XFS_ATTR_INCOMPLETE;
1374 		if ((args->blkno2 == args->blkno) &&
1375 		    (args->index2 <= args->index)) {
1376 			args->index2++;
1377 		}
1378 	}
1379 	xfs_trans_log_buf(args->trans, bp,
1380 			  XFS_DA_LOGRANGE(leaf, entry, sizeof(*entry)));
1381 	ASSERT((args->index == 0) ||
1382 	       (be32_to_cpu(entry->hashval) >= be32_to_cpu((entry-1)->hashval)));
1383 	ASSERT((args->index == ichdr->count - 1) ||
1384 	       (be32_to_cpu(entry->hashval) <= be32_to_cpu((entry+1)->hashval)));
1385 
1386 	/*
1387 	 * For "remote" attribute values, simply note that we need to
1388 	 * allocate space for the "remote" value.  We can't actually
1389 	 * allocate the extents in this transaction, and we can't decide
1390 	 * which blocks they should be as we might allocate more blocks
1391 	 * as part of this transaction (a split operation for example).
1392 	 */
1393 	if (entry->flags & XFS_ATTR_LOCAL) {
1394 		name_loc = xfs_attr3_leaf_name_local(leaf, args->index);
1395 		name_loc->namelen = args->namelen;
1396 		name_loc->valuelen = cpu_to_be16(args->valuelen);
1397 		memcpy((char *)name_loc->nameval, args->name, args->namelen);
1398 		memcpy((char *)&name_loc->nameval[args->namelen], args->value,
1399 				   be16_to_cpu(name_loc->valuelen));
1400 	} else {
1401 		name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
1402 		name_rmt->namelen = args->namelen;
1403 		memcpy((char *)name_rmt->name, args->name, args->namelen);
1404 		entry->flags |= XFS_ATTR_INCOMPLETE;
1405 		/* just in case */
1406 		name_rmt->valuelen = 0;
1407 		name_rmt->valueblk = 0;
1408 		args->rmtblkno = 1;
1409 		args->rmtblkcnt = xfs_attr3_rmt_blocks(mp, args->valuelen);
1410 		args->rmtvaluelen = args->valuelen;
1411 	}
1412 	xfs_trans_log_buf(args->trans, bp,
1413 	     XFS_DA_LOGRANGE(leaf, xfs_attr3_leaf_name(leaf, args->index),
1414 				   xfs_attr_leaf_entsize(leaf, args->index)));
1415 
1416 	/*
1417 	 * Update the control info for this leaf node
1418 	 */
1419 	if (be16_to_cpu(entry->nameidx) < ichdr->firstused)
1420 		ichdr->firstused = be16_to_cpu(entry->nameidx);
1421 
1422 	ASSERT(ichdr->firstused >= ichdr->count * sizeof(xfs_attr_leaf_entry_t)
1423 					+ xfs_attr3_leaf_hdr_size(leaf));
1424 	tmp = (ichdr->count - 1) * sizeof(xfs_attr_leaf_entry_t)
1425 					+ xfs_attr3_leaf_hdr_size(leaf);
1426 
1427 	for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
1428 		if (ichdr->freemap[i].base == tmp) {
1429 			ichdr->freemap[i].base += sizeof(xfs_attr_leaf_entry_t);
1430 			ichdr->freemap[i].size -= sizeof(xfs_attr_leaf_entry_t);
1431 		}
1432 	}
1433 	ichdr->usedbytes += xfs_attr_leaf_entsize(leaf, args->index);
1434 	return 0;
1435 }
1436 
1437 /*
1438  * Garbage collect a leaf attribute list block by copying it to a new buffer.
1439  */
1440 STATIC void
1441 xfs_attr3_leaf_compact(
1442 	struct xfs_da_args	*args,
1443 	struct xfs_attr3_icleaf_hdr *ichdr_dst,
1444 	struct xfs_buf		*bp)
1445 {
1446 	struct xfs_attr_leafblock *leaf_src;
1447 	struct xfs_attr_leafblock *leaf_dst;
1448 	struct xfs_attr3_icleaf_hdr ichdr_src;
1449 	struct xfs_trans	*trans = args->trans;
1450 	char			*tmpbuffer;
1451 
1452 	trace_xfs_attr_leaf_compact(args);
1453 
1454 	tmpbuffer = kmem_alloc(args->geo->blksize, KM_SLEEP);
1455 	memcpy(tmpbuffer, bp->b_addr, args->geo->blksize);
1456 	memset(bp->b_addr, 0, args->geo->blksize);
1457 	leaf_src = (xfs_attr_leafblock_t *)tmpbuffer;
1458 	leaf_dst = bp->b_addr;
1459 
1460 	/*
1461 	 * Copy the on-disk header back into the destination buffer to ensure
1462 	 * all the information in the header that is not part of the incore
1463 	 * header structure is preserved.
1464 	 */
1465 	memcpy(bp->b_addr, tmpbuffer, xfs_attr3_leaf_hdr_size(leaf_src));
1466 
1467 	/* Initialise the incore headers */
1468 	ichdr_src = *ichdr_dst;	/* struct copy */
1469 	ichdr_dst->firstused = args->geo->blksize;
1470 	ichdr_dst->usedbytes = 0;
1471 	ichdr_dst->count = 0;
1472 	ichdr_dst->holes = 0;
1473 	ichdr_dst->freemap[0].base = xfs_attr3_leaf_hdr_size(leaf_src);
1474 	ichdr_dst->freemap[0].size = ichdr_dst->firstused -
1475 						ichdr_dst->freemap[0].base;
1476 
1477 	/* write the header back to initialise the underlying buffer */
1478 	xfs_attr3_leaf_hdr_to_disk(args->geo, leaf_dst, ichdr_dst);
1479 
1480 	/*
1481 	 * Copy all entry's in the same (sorted) order,
1482 	 * but allocate name/value pairs packed and in sequence.
1483 	 */
1484 	xfs_attr3_leaf_moveents(args, leaf_src, &ichdr_src, 0,
1485 				leaf_dst, ichdr_dst, 0, ichdr_src.count);
1486 	/*
1487 	 * this logs the entire buffer, but the caller must write the header
1488 	 * back to the buffer when it is finished modifying it.
1489 	 */
1490 	xfs_trans_log_buf(trans, bp, 0, args->geo->blksize - 1);
1491 
1492 	kmem_free(tmpbuffer);
1493 }
1494 
1495 /*
1496  * Compare two leaf blocks "order".
1497  * Return 0 unless leaf2 should go before leaf1.
1498  */
1499 static int
1500 xfs_attr3_leaf_order(
1501 	struct xfs_buf	*leaf1_bp,
1502 	struct xfs_attr3_icleaf_hdr *leaf1hdr,
1503 	struct xfs_buf	*leaf2_bp,
1504 	struct xfs_attr3_icleaf_hdr *leaf2hdr)
1505 {
1506 	struct xfs_attr_leaf_entry *entries1;
1507 	struct xfs_attr_leaf_entry *entries2;
1508 
1509 	entries1 = xfs_attr3_leaf_entryp(leaf1_bp->b_addr);
1510 	entries2 = xfs_attr3_leaf_entryp(leaf2_bp->b_addr);
1511 	if (leaf1hdr->count > 0 && leaf2hdr->count > 0 &&
1512 	    ((be32_to_cpu(entries2[0].hashval) <
1513 	      be32_to_cpu(entries1[0].hashval)) ||
1514 	     (be32_to_cpu(entries2[leaf2hdr->count - 1].hashval) <
1515 	      be32_to_cpu(entries1[leaf1hdr->count - 1].hashval)))) {
1516 		return 1;
1517 	}
1518 	return 0;
1519 }
1520 
1521 int
1522 xfs_attr_leaf_order(
1523 	struct xfs_buf	*leaf1_bp,
1524 	struct xfs_buf	*leaf2_bp)
1525 {
1526 	struct xfs_attr3_icleaf_hdr ichdr1;
1527 	struct xfs_attr3_icleaf_hdr ichdr2;
1528 	struct xfs_mount *mp = leaf1_bp->b_target->bt_mount;
1529 
1530 	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr1, leaf1_bp->b_addr);
1531 	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr2, leaf2_bp->b_addr);
1532 	return xfs_attr3_leaf_order(leaf1_bp, &ichdr1, leaf2_bp, &ichdr2);
1533 }
1534 
1535 /*
1536  * Redistribute the attribute list entries between two leaf nodes,
1537  * taking into account the size of the new entry.
1538  *
1539  * NOTE: if new block is empty, then it will get the upper half of the
1540  * old block.  At present, all (one) callers pass in an empty second block.
1541  *
1542  * This code adjusts the args->index/blkno and args->index2/blkno2 fields
1543  * to match what it is doing in splitting the attribute leaf block.  Those
1544  * values are used in "atomic rename" operations on attributes.  Note that
1545  * the "new" and "old" values can end up in different blocks.
1546  */
1547 STATIC void
1548 xfs_attr3_leaf_rebalance(
1549 	struct xfs_da_state	*state,
1550 	struct xfs_da_state_blk	*blk1,
1551 	struct xfs_da_state_blk	*blk2)
1552 {
1553 	struct xfs_da_args	*args;
1554 	struct xfs_attr_leafblock *leaf1;
1555 	struct xfs_attr_leafblock *leaf2;
1556 	struct xfs_attr3_icleaf_hdr ichdr1;
1557 	struct xfs_attr3_icleaf_hdr ichdr2;
1558 	struct xfs_attr_leaf_entry *entries1;
1559 	struct xfs_attr_leaf_entry *entries2;
1560 	int			count;
1561 	int			totallen;
1562 	int			max;
1563 	int			space;
1564 	int			swap;
1565 
1566 	/*
1567 	 * Set up environment.
1568 	 */
1569 	ASSERT(blk1->magic == XFS_ATTR_LEAF_MAGIC);
1570 	ASSERT(blk2->magic == XFS_ATTR_LEAF_MAGIC);
1571 	leaf1 = blk1->bp->b_addr;
1572 	leaf2 = blk2->bp->b_addr;
1573 	xfs_attr3_leaf_hdr_from_disk(state->args->geo, &ichdr1, leaf1);
1574 	xfs_attr3_leaf_hdr_from_disk(state->args->geo, &ichdr2, leaf2);
1575 	ASSERT(ichdr2.count == 0);
1576 	args = state->args;
1577 
1578 	trace_xfs_attr_leaf_rebalance(args);
1579 
1580 	/*
1581 	 * Check ordering of blocks, reverse if it makes things simpler.
1582 	 *
1583 	 * NOTE: Given that all (current) callers pass in an empty
1584 	 * second block, this code should never set "swap".
1585 	 */
1586 	swap = 0;
1587 	if (xfs_attr3_leaf_order(blk1->bp, &ichdr1, blk2->bp, &ichdr2)) {
1588 		swap(blk1, blk2);
1589 
1590 		/* swap structures rather than reconverting them */
1591 		swap(ichdr1, ichdr2);
1592 
1593 		leaf1 = blk1->bp->b_addr;
1594 		leaf2 = blk2->bp->b_addr;
1595 		swap = 1;
1596 	}
1597 
1598 	/*
1599 	 * Examine entries until we reduce the absolute difference in
1600 	 * byte usage between the two blocks to a minimum.  Then get
1601 	 * the direction to copy and the number of elements to move.
1602 	 *
1603 	 * "inleaf" is true if the new entry should be inserted into blk1.
1604 	 * If "swap" is also true, then reverse the sense of "inleaf".
1605 	 */
1606 	state->inleaf = xfs_attr3_leaf_figure_balance(state, blk1, &ichdr1,
1607 						      blk2, &ichdr2,
1608 						      &count, &totallen);
1609 	if (swap)
1610 		state->inleaf = !state->inleaf;
1611 
1612 	/*
1613 	 * Move any entries required from leaf to leaf:
1614 	 */
1615 	if (count < ichdr1.count) {
1616 		/*
1617 		 * Figure the total bytes to be added to the destination leaf.
1618 		 */
1619 		/* number entries being moved */
1620 		count = ichdr1.count - count;
1621 		space  = ichdr1.usedbytes - totallen;
1622 		space += count * sizeof(xfs_attr_leaf_entry_t);
1623 
1624 		/*
1625 		 * leaf2 is the destination, compact it if it looks tight.
1626 		 */
1627 		max  = ichdr2.firstused - xfs_attr3_leaf_hdr_size(leaf1);
1628 		max -= ichdr2.count * sizeof(xfs_attr_leaf_entry_t);
1629 		if (space > max)
1630 			xfs_attr3_leaf_compact(args, &ichdr2, blk2->bp);
1631 
1632 		/*
1633 		 * Move high entries from leaf1 to low end of leaf2.
1634 		 */
1635 		xfs_attr3_leaf_moveents(args, leaf1, &ichdr1,
1636 				ichdr1.count - count, leaf2, &ichdr2, 0, count);
1637 
1638 	} else if (count > ichdr1.count) {
1639 		/*
1640 		 * I assert that since all callers pass in an empty
1641 		 * second buffer, this code should never execute.
1642 		 */
1643 		ASSERT(0);
1644 
1645 		/*
1646 		 * Figure the total bytes to be added to the destination leaf.
1647 		 */
1648 		/* number entries being moved */
1649 		count -= ichdr1.count;
1650 		space  = totallen - ichdr1.usedbytes;
1651 		space += count * sizeof(xfs_attr_leaf_entry_t);
1652 
1653 		/*
1654 		 * leaf1 is the destination, compact it if it looks tight.
1655 		 */
1656 		max  = ichdr1.firstused - xfs_attr3_leaf_hdr_size(leaf1);
1657 		max -= ichdr1.count * sizeof(xfs_attr_leaf_entry_t);
1658 		if (space > max)
1659 			xfs_attr3_leaf_compact(args, &ichdr1, blk1->bp);
1660 
1661 		/*
1662 		 * Move low entries from leaf2 to high end of leaf1.
1663 		 */
1664 		xfs_attr3_leaf_moveents(args, leaf2, &ichdr2, 0, leaf1, &ichdr1,
1665 					ichdr1.count, count);
1666 	}
1667 
1668 	xfs_attr3_leaf_hdr_to_disk(state->args->geo, leaf1, &ichdr1);
1669 	xfs_attr3_leaf_hdr_to_disk(state->args->geo, leaf2, &ichdr2);
1670 	xfs_trans_log_buf(args->trans, blk1->bp, 0, args->geo->blksize - 1);
1671 	xfs_trans_log_buf(args->trans, blk2->bp, 0, args->geo->blksize - 1);
1672 
1673 	/*
1674 	 * Copy out last hashval in each block for B-tree code.
1675 	 */
1676 	entries1 = xfs_attr3_leaf_entryp(leaf1);
1677 	entries2 = xfs_attr3_leaf_entryp(leaf2);
1678 	blk1->hashval = be32_to_cpu(entries1[ichdr1.count - 1].hashval);
1679 	blk2->hashval = be32_to_cpu(entries2[ichdr2.count - 1].hashval);
1680 
1681 	/*
1682 	 * Adjust the expected index for insertion.
1683 	 * NOTE: this code depends on the (current) situation that the
1684 	 * second block was originally empty.
1685 	 *
1686 	 * If the insertion point moved to the 2nd block, we must adjust
1687 	 * the index.  We must also track the entry just following the
1688 	 * new entry for use in an "atomic rename" operation, that entry
1689 	 * is always the "old" entry and the "new" entry is what we are
1690 	 * inserting.  The index/blkno fields refer to the "old" entry,
1691 	 * while the index2/blkno2 fields refer to the "new" entry.
1692 	 */
1693 	if (blk1->index > ichdr1.count) {
1694 		ASSERT(state->inleaf == 0);
1695 		blk2->index = blk1->index - ichdr1.count;
1696 		args->index = args->index2 = blk2->index;
1697 		args->blkno = args->blkno2 = blk2->blkno;
1698 	} else if (blk1->index == ichdr1.count) {
1699 		if (state->inleaf) {
1700 			args->index = blk1->index;
1701 			args->blkno = blk1->blkno;
1702 			args->index2 = 0;
1703 			args->blkno2 = blk2->blkno;
1704 		} else {
1705 			/*
1706 			 * On a double leaf split, the original attr location
1707 			 * is already stored in blkno2/index2, so don't
1708 			 * overwrite it overwise we corrupt the tree.
1709 			 */
1710 			blk2->index = blk1->index - ichdr1.count;
1711 			args->index = blk2->index;
1712 			args->blkno = blk2->blkno;
1713 			if (!state->extravalid) {
1714 				/*
1715 				 * set the new attr location to match the old
1716 				 * one and let the higher level split code
1717 				 * decide where in the leaf to place it.
1718 				 */
1719 				args->index2 = blk2->index;
1720 				args->blkno2 = blk2->blkno;
1721 			}
1722 		}
1723 	} else {
1724 		ASSERT(state->inleaf == 1);
1725 		args->index = args->index2 = blk1->index;
1726 		args->blkno = args->blkno2 = blk1->blkno;
1727 	}
1728 }
1729 
1730 /*
1731  * Examine entries until we reduce the absolute difference in
1732  * byte usage between the two blocks to a minimum.
1733  * GROT: Is this really necessary?  With other than a 512 byte blocksize,
1734  * GROT: there will always be enough room in either block for a new entry.
1735  * GROT: Do a double-split for this case?
1736  */
1737 STATIC int
1738 xfs_attr3_leaf_figure_balance(
1739 	struct xfs_da_state		*state,
1740 	struct xfs_da_state_blk		*blk1,
1741 	struct xfs_attr3_icleaf_hdr	*ichdr1,
1742 	struct xfs_da_state_blk		*blk2,
1743 	struct xfs_attr3_icleaf_hdr	*ichdr2,
1744 	int				*countarg,
1745 	int				*usedbytesarg)
1746 {
1747 	struct xfs_attr_leafblock	*leaf1 = blk1->bp->b_addr;
1748 	struct xfs_attr_leafblock	*leaf2 = blk2->bp->b_addr;
1749 	struct xfs_attr_leaf_entry	*entry;
1750 	int				count;
1751 	int				max;
1752 	int				index;
1753 	int				totallen = 0;
1754 	int				half;
1755 	int				lastdelta;
1756 	int				foundit = 0;
1757 	int				tmp;
1758 
1759 	/*
1760 	 * Examine entries until we reduce the absolute difference in
1761 	 * byte usage between the two blocks to a minimum.
1762 	 */
1763 	max = ichdr1->count + ichdr2->count;
1764 	half = (max + 1) * sizeof(*entry);
1765 	half += ichdr1->usedbytes + ichdr2->usedbytes +
1766 			xfs_attr_leaf_newentsize(state->args, NULL);
1767 	half /= 2;
1768 	lastdelta = state->args->geo->blksize;
1769 	entry = xfs_attr3_leaf_entryp(leaf1);
1770 	for (count = index = 0; count < max; entry++, index++, count++) {
1771 
1772 #define XFS_ATTR_ABS(A)	(((A) < 0) ? -(A) : (A))
1773 		/*
1774 		 * The new entry is in the first block, account for it.
1775 		 */
1776 		if (count == blk1->index) {
1777 			tmp = totallen + sizeof(*entry) +
1778 				xfs_attr_leaf_newentsize(state->args, NULL);
1779 			if (XFS_ATTR_ABS(half - tmp) > lastdelta)
1780 				break;
1781 			lastdelta = XFS_ATTR_ABS(half - tmp);
1782 			totallen = tmp;
1783 			foundit = 1;
1784 		}
1785 
1786 		/*
1787 		 * Wrap around into the second block if necessary.
1788 		 */
1789 		if (count == ichdr1->count) {
1790 			leaf1 = leaf2;
1791 			entry = xfs_attr3_leaf_entryp(leaf1);
1792 			index = 0;
1793 		}
1794 
1795 		/*
1796 		 * Figure out if next leaf entry would be too much.
1797 		 */
1798 		tmp = totallen + sizeof(*entry) + xfs_attr_leaf_entsize(leaf1,
1799 									index);
1800 		if (XFS_ATTR_ABS(half - tmp) > lastdelta)
1801 			break;
1802 		lastdelta = XFS_ATTR_ABS(half - tmp);
1803 		totallen = tmp;
1804 #undef XFS_ATTR_ABS
1805 	}
1806 
1807 	/*
1808 	 * Calculate the number of usedbytes that will end up in lower block.
1809 	 * If new entry not in lower block, fix up the count.
1810 	 */
1811 	totallen -= count * sizeof(*entry);
1812 	if (foundit) {
1813 		totallen -= sizeof(*entry) +
1814 				xfs_attr_leaf_newentsize(state->args, NULL);
1815 	}
1816 
1817 	*countarg = count;
1818 	*usedbytesarg = totallen;
1819 	return foundit;
1820 }
1821 
1822 /*========================================================================
1823  * Routines used for shrinking the Btree.
1824  *========================================================================*/
1825 
1826 /*
1827  * Check a leaf block and its neighbors to see if the block should be
1828  * collapsed into one or the other neighbor.  Always keep the block
1829  * with the smaller block number.
1830  * If the current block is over 50% full, don't try to join it, return 0.
1831  * If the block is empty, fill in the state structure and return 2.
1832  * If it can be collapsed, fill in the state structure and return 1.
1833  * If nothing can be done, return 0.
1834  *
1835  * GROT: allow for INCOMPLETE entries in calculation.
1836  */
1837 int
1838 xfs_attr3_leaf_toosmall(
1839 	struct xfs_da_state	*state,
1840 	int			*action)
1841 {
1842 	struct xfs_attr_leafblock *leaf;
1843 	struct xfs_da_state_blk	*blk;
1844 	struct xfs_attr3_icleaf_hdr ichdr;
1845 	struct xfs_buf		*bp;
1846 	xfs_dablk_t		blkno;
1847 	int			bytes;
1848 	int			forward;
1849 	int			error;
1850 	int			retval;
1851 	int			i;
1852 
1853 	trace_xfs_attr_leaf_toosmall(state->args);
1854 
1855 	/*
1856 	 * Check for the degenerate case of the block being over 50% full.
1857 	 * If so, it's not worth even looking to see if we might be able
1858 	 * to coalesce with a sibling.
1859 	 */
1860 	blk = &state->path.blk[ state->path.active-1 ];
1861 	leaf = blk->bp->b_addr;
1862 	xfs_attr3_leaf_hdr_from_disk(state->args->geo, &ichdr, leaf);
1863 	bytes = xfs_attr3_leaf_hdr_size(leaf) +
1864 		ichdr.count * sizeof(xfs_attr_leaf_entry_t) +
1865 		ichdr.usedbytes;
1866 	if (bytes > (state->args->geo->blksize >> 1)) {
1867 		*action = 0;	/* blk over 50%, don't try to join */
1868 		return 0;
1869 	}
1870 
1871 	/*
1872 	 * Check for the degenerate case of the block being empty.
1873 	 * If the block is empty, we'll simply delete it, no need to
1874 	 * coalesce it with a sibling block.  We choose (arbitrarily)
1875 	 * to merge with the forward block unless it is NULL.
1876 	 */
1877 	if (ichdr.count == 0) {
1878 		/*
1879 		 * Make altpath point to the block we want to keep and
1880 		 * path point to the block we want to drop (this one).
1881 		 */
1882 		forward = (ichdr.forw != 0);
1883 		memcpy(&state->altpath, &state->path, sizeof(state->path));
1884 		error = xfs_da3_path_shift(state, &state->altpath, forward,
1885 						 0, &retval);
1886 		if (error)
1887 			return error;
1888 		if (retval) {
1889 			*action = 0;
1890 		} else {
1891 			*action = 2;
1892 		}
1893 		return 0;
1894 	}
1895 
1896 	/*
1897 	 * Examine each sibling block to see if we can coalesce with
1898 	 * at least 25% free space to spare.  We need to figure out
1899 	 * whether to merge with the forward or the backward block.
1900 	 * We prefer coalescing with the lower numbered sibling so as
1901 	 * to shrink an attribute list over time.
1902 	 */
1903 	/* start with smaller blk num */
1904 	forward = ichdr.forw < ichdr.back;
1905 	for (i = 0; i < 2; forward = !forward, i++) {
1906 		struct xfs_attr3_icleaf_hdr ichdr2;
1907 		if (forward)
1908 			blkno = ichdr.forw;
1909 		else
1910 			blkno = ichdr.back;
1911 		if (blkno == 0)
1912 			continue;
1913 		error = xfs_attr3_leaf_read(state->args->trans, state->args->dp,
1914 					blkno, -1, &bp);
1915 		if (error)
1916 			return error;
1917 
1918 		xfs_attr3_leaf_hdr_from_disk(state->args->geo, &ichdr2, bp->b_addr);
1919 
1920 		bytes = state->args->geo->blksize -
1921 			(state->args->geo->blksize >> 2) -
1922 			ichdr.usedbytes - ichdr2.usedbytes -
1923 			((ichdr.count + ichdr2.count) *
1924 					sizeof(xfs_attr_leaf_entry_t)) -
1925 			xfs_attr3_leaf_hdr_size(leaf);
1926 
1927 		xfs_trans_brelse(state->args->trans, bp);
1928 		if (bytes >= 0)
1929 			break;	/* fits with at least 25% to spare */
1930 	}
1931 	if (i >= 2) {
1932 		*action = 0;
1933 		return 0;
1934 	}
1935 
1936 	/*
1937 	 * Make altpath point to the block we want to keep (the lower
1938 	 * numbered block) and path point to the block we want to drop.
1939 	 */
1940 	memcpy(&state->altpath, &state->path, sizeof(state->path));
1941 	if (blkno < blk->blkno) {
1942 		error = xfs_da3_path_shift(state, &state->altpath, forward,
1943 						 0, &retval);
1944 	} else {
1945 		error = xfs_da3_path_shift(state, &state->path, forward,
1946 						 0, &retval);
1947 	}
1948 	if (error)
1949 		return error;
1950 	if (retval) {
1951 		*action = 0;
1952 	} else {
1953 		*action = 1;
1954 	}
1955 	return 0;
1956 }
1957 
1958 /*
1959  * Remove a name from the leaf attribute list structure.
1960  *
1961  * Return 1 if leaf is less than 37% full, 0 if >= 37% full.
1962  * If two leaves are 37% full, when combined they will leave 25% free.
1963  */
1964 int
1965 xfs_attr3_leaf_remove(
1966 	struct xfs_buf		*bp,
1967 	struct xfs_da_args	*args)
1968 {
1969 	struct xfs_attr_leafblock *leaf;
1970 	struct xfs_attr3_icleaf_hdr ichdr;
1971 	struct xfs_attr_leaf_entry *entry;
1972 	int			before;
1973 	int			after;
1974 	int			smallest;
1975 	int			entsize;
1976 	int			tablesize;
1977 	int			tmp;
1978 	int			i;
1979 
1980 	trace_xfs_attr_leaf_remove(args);
1981 
1982 	leaf = bp->b_addr;
1983 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
1984 
1985 	ASSERT(ichdr.count > 0 && ichdr.count < args->geo->blksize / 8);
1986 	ASSERT(args->index >= 0 && args->index < ichdr.count);
1987 	ASSERT(ichdr.firstused >= ichdr.count * sizeof(*entry) +
1988 					xfs_attr3_leaf_hdr_size(leaf));
1989 
1990 	entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
1991 
1992 	ASSERT(be16_to_cpu(entry->nameidx) >= ichdr.firstused);
1993 	ASSERT(be16_to_cpu(entry->nameidx) < args->geo->blksize);
1994 
1995 	/*
1996 	 * Scan through free region table:
1997 	 *    check for adjacency of free'd entry with an existing one,
1998 	 *    find smallest free region in case we need to replace it,
1999 	 *    adjust any map that borders the entry table,
2000 	 */
2001 	tablesize = ichdr.count * sizeof(xfs_attr_leaf_entry_t)
2002 					+ xfs_attr3_leaf_hdr_size(leaf);
2003 	tmp = ichdr.freemap[0].size;
2004 	before = after = -1;
2005 	smallest = XFS_ATTR_LEAF_MAPSIZE - 1;
2006 	entsize = xfs_attr_leaf_entsize(leaf, args->index);
2007 	for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
2008 		ASSERT(ichdr.freemap[i].base < args->geo->blksize);
2009 		ASSERT(ichdr.freemap[i].size < args->geo->blksize);
2010 		if (ichdr.freemap[i].base == tablesize) {
2011 			ichdr.freemap[i].base -= sizeof(xfs_attr_leaf_entry_t);
2012 			ichdr.freemap[i].size += sizeof(xfs_attr_leaf_entry_t);
2013 		}
2014 
2015 		if (ichdr.freemap[i].base + ichdr.freemap[i].size ==
2016 				be16_to_cpu(entry->nameidx)) {
2017 			before = i;
2018 		} else if (ichdr.freemap[i].base ==
2019 				(be16_to_cpu(entry->nameidx) + entsize)) {
2020 			after = i;
2021 		} else if (ichdr.freemap[i].size < tmp) {
2022 			tmp = ichdr.freemap[i].size;
2023 			smallest = i;
2024 		}
2025 	}
2026 
2027 	/*
2028 	 * Coalesce adjacent freemap regions,
2029 	 * or replace the smallest region.
2030 	 */
2031 	if ((before >= 0) || (after >= 0)) {
2032 		if ((before >= 0) && (after >= 0)) {
2033 			ichdr.freemap[before].size += entsize;
2034 			ichdr.freemap[before].size += ichdr.freemap[after].size;
2035 			ichdr.freemap[after].base = 0;
2036 			ichdr.freemap[after].size = 0;
2037 		} else if (before >= 0) {
2038 			ichdr.freemap[before].size += entsize;
2039 		} else {
2040 			ichdr.freemap[after].base = be16_to_cpu(entry->nameidx);
2041 			ichdr.freemap[after].size += entsize;
2042 		}
2043 	} else {
2044 		/*
2045 		 * Replace smallest region (if it is smaller than free'd entry)
2046 		 */
2047 		if (ichdr.freemap[smallest].size < entsize) {
2048 			ichdr.freemap[smallest].base = be16_to_cpu(entry->nameidx);
2049 			ichdr.freemap[smallest].size = entsize;
2050 		}
2051 	}
2052 
2053 	/*
2054 	 * Did we remove the first entry?
2055 	 */
2056 	if (be16_to_cpu(entry->nameidx) == ichdr.firstused)
2057 		smallest = 1;
2058 	else
2059 		smallest = 0;
2060 
2061 	/*
2062 	 * Compress the remaining entries and zero out the removed stuff.
2063 	 */
2064 	memset(xfs_attr3_leaf_name(leaf, args->index), 0, entsize);
2065 	ichdr.usedbytes -= entsize;
2066 	xfs_trans_log_buf(args->trans, bp,
2067 	     XFS_DA_LOGRANGE(leaf, xfs_attr3_leaf_name(leaf, args->index),
2068 				   entsize));
2069 
2070 	tmp = (ichdr.count - args->index) * sizeof(xfs_attr_leaf_entry_t);
2071 	memmove(entry, entry + 1, tmp);
2072 	ichdr.count--;
2073 	xfs_trans_log_buf(args->trans, bp,
2074 	    XFS_DA_LOGRANGE(leaf, entry, tmp + sizeof(xfs_attr_leaf_entry_t)));
2075 
2076 	entry = &xfs_attr3_leaf_entryp(leaf)[ichdr.count];
2077 	memset(entry, 0, sizeof(xfs_attr_leaf_entry_t));
2078 
2079 	/*
2080 	 * If we removed the first entry, re-find the first used byte
2081 	 * in the name area.  Note that if the entry was the "firstused",
2082 	 * then we don't have a "hole" in our block resulting from
2083 	 * removing the name.
2084 	 */
2085 	if (smallest) {
2086 		tmp = args->geo->blksize;
2087 		entry = xfs_attr3_leaf_entryp(leaf);
2088 		for (i = ichdr.count - 1; i >= 0; entry++, i--) {
2089 			ASSERT(be16_to_cpu(entry->nameidx) >= ichdr.firstused);
2090 			ASSERT(be16_to_cpu(entry->nameidx) < args->geo->blksize);
2091 
2092 			if (be16_to_cpu(entry->nameidx) < tmp)
2093 				tmp = be16_to_cpu(entry->nameidx);
2094 		}
2095 		ichdr.firstused = tmp;
2096 		ASSERT(ichdr.firstused != 0);
2097 	} else {
2098 		ichdr.holes = 1;	/* mark as needing compaction */
2099 	}
2100 	xfs_attr3_leaf_hdr_to_disk(args->geo, leaf, &ichdr);
2101 	xfs_trans_log_buf(args->trans, bp,
2102 			  XFS_DA_LOGRANGE(leaf, &leaf->hdr,
2103 					  xfs_attr3_leaf_hdr_size(leaf)));
2104 
2105 	/*
2106 	 * Check if leaf is less than 50% full, caller may want to
2107 	 * "join" the leaf with a sibling if so.
2108 	 */
2109 	tmp = ichdr.usedbytes + xfs_attr3_leaf_hdr_size(leaf) +
2110 	      ichdr.count * sizeof(xfs_attr_leaf_entry_t);
2111 
2112 	return tmp < args->geo->magicpct; /* leaf is < 37% full */
2113 }
2114 
2115 /*
2116  * Move all the attribute list entries from drop_leaf into save_leaf.
2117  */
2118 void
2119 xfs_attr3_leaf_unbalance(
2120 	struct xfs_da_state	*state,
2121 	struct xfs_da_state_blk	*drop_blk,
2122 	struct xfs_da_state_blk	*save_blk)
2123 {
2124 	struct xfs_attr_leafblock *drop_leaf = drop_blk->bp->b_addr;
2125 	struct xfs_attr_leafblock *save_leaf = save_blk->bp->b_addr;
2126 	struct xfs_attr3_icleaf_hdr drophdr;
2127 	struct xfs_attr3_icleaf_hdr savehdr;
2128 	struct xfs_attr_leaf_entry *entry;
2129 
2130 	trace_xfs_attr_leaf_unbalance(state->args);
2131 
2132 	drop_leaf = drop_blk->bp->b_addr;
2133 	save_leaf = save_blk->bp->b_addr;
2134 	xfs_attr3_leaf_hdr_from_disk(state->args->geo, &drophdr, drop_leaf);
2135 	xfs_attr3_leaf_hdr_from_disk(state->args->geo, &savehdr, save_leaf);
2136 	entry = xfs_attr3_leaf_entryp(drop_leaf);
2137 
2138 	/*
2139 	 * Save last hashval from dying block for later Btree fixup.
2140 	 */
2141 	drop_blk->hashval = be32_to_cpu(entry[drophdr.count - 1].hashval);
2142 
2143 	/*
2144 	 * Check if we need a temp buffer, or can we do it in place.
2145 	 * Note that we don't check "leaf" for holes because we will
2146 	 * always be dropping it, toosmall() decided that for us already.
2147 	 */
2148 	if (savehdr.holes == 0) {
2149 		/*
2150 		 * dest leaf has no holes, so we add there.  May need
2151 		 * to make some room in the entry array.
2152 		 */
2153 		if (xfs_attr3_leaf_order(save_blk->bp, &savehdr,
2154 					 drop_blk->bp, &drophdr)) {
2155 			xfs_attr3_leaf_moveents(state->args,
2156 						drop_leaf, &drophdr, 0,
2157 						save_leaf, &savehdr, 0,
2158 						drophdr.count);
2159 		} else {
2160 			xfs_attr3_leaf_moveents(state->args,
2161 						drop_leaf, &drophdr, 0,
2162 						save_leaf, &savehdr,
2163 						savehdr.count, drophdr.count);
2164 		}
2165 	} else {
2166 		/*
2167 		 * Destination has holes, so we make a temporary copy
2168 		 * of the leaf and add them both to that.
2169 		 */
2170 		struct xfs_attr_leafblock *tmp_leaf;
2171 		struct xfs_attr3_icleaf_hdr tmphdr;
2172 
2173 		tmp_leaf = kmem_zalloc(state->args->geo->blksize, KM_SLEEP);
2174 
2175 		/*
2176 		 * Copy the header into the temp leaf so that all the stuff
2177 		 * not in the incore header is present and gets copied back in
2178 		 * once we've moved all the entries.
2179 		 */
2180 		memcpy(tmp_leaf, save_leaf, xfs_attr3_leaf_hdr_size(save_leaf));
2181 
2182 		memset(&tmphdr, 0, sizeof(tmphdr));
2183 		tmphdr.magic = savehdr.magic;
2184 		tmphdr.forw = savehdr.forw;
2185 		tmphdr.back = savehdr.back;
2186 		tmphdr.firstused = state->args->geo->blksize;
2187 
2188 		/* write the header to the temp buffer to initialise it */
2189 		xfs_attr3_leaf_hdr_to_disk(state->args->geo, tmp_leaf, &tmphdr);
2190 
2191 		if (xfs_attr3_leaf_order(save_blk->bp, &savehdr,
2192 					 drop_blk->bp, &drophdr)) {
2193 			xfs_attr3_leaf_moveents(state->args,
2194 						drop_leaf, &drophdr, 0,
2195 						tmp_leaf, &tmphdr, 0,
2196 						drophdr.count);
2197 			xfs_attr3_leaf_moveents(state->args,
2198 						save_leaf, &savehdr, 0,
2199 						tmp_leaf, &tmphdr, tmphdr.count,
2200 						savehdr.count);
2201 		} else {
2202 			xfs_attr3_leaf_moveents(state->args,
2203 						save_leaf, &savehdr, 0,
2204 						tmp_leaf, &tmphdr, 0,
2205 						savehdr.count);
2206 			xfs_attr3_leaf_moveents(state->args,
2207 						drop_leaf, &drophdr, 0,
2208 						tmp_leaf, &tmphdr, tmphdr.count,
2209 						drophdr.count);
2210 		}
2211 		memcpy(save_leaf, tmp_leaf, state->args->geo->blksize);
2212 		savehdr = tmphdr; /* struct copy */
2213 		kmem_free(tmp_leaf);
2214 	}
2215 
2216 	xfs_attr3_leaf_hdr_to_disk(state->args->geo, save_leaf, &savehdr);
2217 	xfs_trans_log_buf(state->args->trans, save_blk->bp, 0,
2218 					   state->args->geo->blksize - 1);
2219 
2220 	/*
2221 	 * Copy out last hashval in each block for B-tree code.
2222 	 */
2223 	entry = xfs_attr3_leaf_entryp(save_leaf);
2224 	save_blk->hashval = be32_to_cpu(entry[savehdr.count - 1].hashval);
2225 }
2226 
2227 /*========================================================================
2228  * Routines used for finding things in the Btree.
2229  *========================================================================*/
2230 
2231 /*
2232  * Look up a name in a leaf attribute list structure.
2233  * This is the internal routine, it uses the caller's buffer.
2234  *
2235  * Note that duplicate keys are allowed, but only check within the
2236  * current leaf node.  The Btree code must check in adjacent leaf nodes.
2237  *
2238  * Return in args->index the index into the entry[] array of either
2239  * the found entry, or where the entry should have been (insert before
2240  * that entry).
2241  *
2242  * Don't change the args->value unless we find the attribute.
2243  */
2244 int
2245 xfs_attr3_leaf_lookup_int(
2246 	struct xfs_buf		*bp,
2247 	struct xfs_da_args	*args)
2248 {
2249 	struct xfs_attr_leafblock *leaf;
2250 	struct xfs_attr3_icleaf_hdr ichdr;
2251 	struct xfs_attr_leaf_entry *entry;
2252 	struct xfs_attr_leaf_entry *entries;
2253 	struct xfs_attr_leaf_name_local *name_loc;
2254 	struct xfs_attr_leaf_name_remote *name_rmt;
2255 	xfs_dahash_t		hashval;
2256 	int			probe;
2257 	int			span;
2258 
2259 	trace_xfs_attr_leaf_lookup(args);
2260 
2261 	leaf = bp->b_addr;
2262 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
2263 	entries = xfs_attr3_leaf_entryp(leaf);
2264 	if (ichdr.count >= args->geo->blksize / 8)
2265 		return -EFSCORRUPTED;
2266 
2267 	/*
2268 	 * Binary search.  (note: small blocks will skip this loop)
2269 	 */
2270 	hashval = args->hashval;
2271 	probe = span = ichdr.count / 2;
2272 	for (entry = &entries[probe]; span > 4; entry = &entries[probe]) {
2273 		span /= 2;
2274 		if (be32_to_cpu(entry->hashval) < hashval)
2275 			probe += span;
2276 		else if (be32_to_cpu(entry->hashval) > hashval)
2277 			probe -= span;
2278 		else
2279 			break;
2280 	}
2281 	if (!(probe >= 0 && (!ichdr.count || probe < ichdr.count)))
2282 		return -EFSCORRUPTED;
2283 	if (!(span <= 4 || be32_to_cpu(entry->hashval) == hashval))
2284 		return -EFSCORRUPTED;
2285 
2286 	/*
2287 	 * Since we may have duplicate hashval's, find the first matching
2288 	 * hashval in the leaf.
2289 	 */
2290 	while (probe > 0 && be32_to_cpu(entry->hashval) >= hashval) {
2291 		entry--;
2292 		probe--;
2293 	}
2294 	while (probe < ichdr.count &&
2295 	       be32_to_cpu(entry->hashval) < hashval) {
2296 		entry++;
2297 		probe++;
2298 	}
2299 	if (probe == ichdr.count || be32_to_cpu(entry->hashval) != hashval) {
2300 		args->index = probe;
2301 		return -ENOATTR;
2302 	}
2303 
2304 	/*
2305 	 * Duplicate keys may be present, so search all of them for a match.
2306 	 */
2307 	for (; probe < ichdr.count && (be32_to_cpu(entry->hashval) == hashval);
2308 			entry++, probe++) {
2309 /*
2310  * GROT: Add code to remove incomplete entries.
2311  */
2312 		/*
2313 		 * If we are looking for INCOMPLETE entries, show only those.
2314 		 * If we are looking for complete entries, show only those.
2315 		 */
2316 		if ((args->flags & XFS_ATTR_INCOMPLETE) !=
2317 		    (entry->flags & XFS_ATTR_INCOMPLETE)) {
2318 			continue;
2319 		}
2320 		if (entry->flags & XFS_ATTR_LOCAL) {
2321 			name_loc = xfs_attr3_leaf_name_local(leaf, probe);
2322 			if (name_loc->namelen != args->namelen)
2323 				continue;
2324 			if (memcmp(args->name, name_loc->nameval,
2325 							args->namelen) != 0)
2326 				continue;
2327 			if (!xfs_attr_namesp_match(args->flags, entry->flags))
2328 				continue;
2329 			args->index = probe;
2330 			return -EEXIST;
2331 		} else {
2332 			name_rmt = xfs_attr3_leaf_name_remote(leaf, probe);
2333 			if (name_rmt->namelen != args->namelen)
2334 				continue;
2335 			if (memcmp(args->name, name_rmt->name,
2336 							args->namelen) != 0)
2337 				continue;
2338 			if (!xfs_attr_namesp_match(args->flags, entry->flags))
2339 				continue;
2340 			args->index = probe;
2341 			args->rmtvaluelen = be32_to_cpu(name_rmt->valuelen);
2342 			args->rmtblkno = be32_to_cpu(name_rmt->valueblk);
2343 			args->rmtblkcnt = xfs_attr3_rmt_blocks(
2344 							args->dp->i_mount,
2345 							args->rmtvaluelen);
2346 			return -EEXIST;
2347 		}
2348 	}
2349 	args->index = probe;
2350 	return -ENOATTR;
2351 }
2352 
2353 /*
2354  * Get the value associated with an attribute name from a leaf attribute
2355  * list structure.
2356  */
2357 int
2358 xfs_attr3_leaf_getvalue(
2359 	struct xfs_buf		*bp,
2360 	struct xfs_da_args	*args)
2361 {
2362 	struct xfs_attr_leafblock *leaf;
2363 	struct xfs_attr3_icleaf_hdr ichdr;
2364 	struct xfs_attr_leaf_entry *entry;
2365 	struct xfs_attr_leaf_name_local *name_loc;
2366 	struct xfs_attr_leaf_name_remote *name_rmt;
2367 	int			valuelen;
2368 
2369 	leaf = bp->b_addr;
2370 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
2371 	ASSERT(ichdr.count < args->geo->blksize / 8);
2372 	ASSERT(args->index < ichdr.count);
2373 
2374 	entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
2375 	if (entry->flags & XFS_ATTR_LOCAL) {
2376 		name_loc = xfs_attr3_leaf_name_local(leaf, args->index);
2377 		ASSERT(name_loc->namelen == args->namelen);
2378 		ASSERT(memcmp(args->name, name_loc->nameval, args->namelen) == 0);
2379 		valuelen = be16_to_cpu(name_loc->valuelen);
2380 		if (args->flags & ATTR_KERNOVAL) {
2381 			args->valuelen = valuelen;
2382 			return 0;
2383 		}
2384 		if (args->valuelen < valuelen) {
2385 			args->valuelen = valuelen;
2386 			return -ERANGE;
2387 		}
2388 		args->valuelen = valuelen;
2389 		memcpy(args->value, &name_loc->nameval[args->namelen], valuelen);
2390 	} else {
2391 		name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
2392 		ASSERT(name_rmt->namelen == args->namelen);
2393 		ASSERT(memcmp(args->name, name_rmt->name, args->namelen) == 0);
2394 		args->rmtvaluelen = be32_to_cpu(name_rmt->valuelen);
2395 		args->rmtblkno = be32_to_cpu(name_rmt->valueblk);
2396 		args->rmtblkcnt = xfs_attr3_rmt_blocks(args->dp->i_mount,
2397 						       args->rmtvaluelen);
2398 		if (args->flags & ATTR_KERNOVAL) {
2399 			args->valuelen = args->rmtvaluelen;
2400 			return 0;
2401 		}
2402 		if (args->valuelen < args->rmtvaluelen) {
2403 			args->valuelen = args->rmtvaluelen;
2404 			return -ERANGE;
2405 		}
2406 		args->valuelen = args->rmtvaluelen;
2407 	}
2408 	return 0;
2409 }
2410 
2411 /*========================================================================
2412  * Utility routines.
2413  *========================================================================*/
2414 
2415 /*
2416  * Move the indicated entries from one leaf to another.
2417  * NOTE: this routine modifies both source and destination leaves.
2418  */
2419 /*ARGSUSED*/
2420 STATIC void
2421 xfs_attr3_leaf_moveents(
2422 	struct xfs_da_args		*args,
2423 	struct xfs_attr_leafblock	*leaf_s,
2424 	struct xfs_attr3_icleaf_hdr	*ichdr_s,
2425 	int				start_s,
2426 	struct xfs_attr_leafblock	*leaf_d,
2427 	struct xfs_attr3_icleaf_hdr	*ichdr_d,
2428 	int				start_d,
2429 	int				count)
2430 {
2431 	struct xfs_attr_leaf_entry	*entry_s;
2432 	struct xfs_attr_leaf_entry	*entry_d;
2433 	int				desti;
2434 	int				tmp;
2435 	int				i;
2436 
2437 	/*
2438 	 * Check for nothing to do.
2439 	 */
2440 	if (count == 0)
2441 		return;
2442 
2443 	/*
2444 	 * Set up environment.
2445 	 */
2446 	ASSERT(ichdr_s->magic == XFS_ATTR_LEAF_MAGIC ||
2447 	       ichdr_s->magic == XFS_ATTR3_LEAF_MAGIC);
2448 	ASSERT(ichdr_s->magic == ichdr_d->magic);
2449 	ASSERT(ichdr_s->count > 0 && ichdr_s->count < args->geo->blksize / 8);
2450 	ASSERT(ichdr_s->firstused >= (ichdr_s->count * sizeof(*entry_s))
2451 					+ xfs_attr3_leaf_hdr_size(leaf_s));
2452 	ASSERT(ichdr_d->count < args->geo->blksize / 8);
2453 	ASSERT(ichdr_d->firstused >= (ichdr_d->count * sizeof(*entry_d))
2454 					+ xfs_attr3_leaf_hdr_size(leaf_d));
2455 
2456 	ASSERT(start_s < ichdr_s->count);
2457 	ASSERT(start_d <= ichdr_d->count);
2458 	ASSERT(count <= ichdr_s->count);
2459 
2460 
2461 	/*
2462 	 * Move the entries in the destination leaf up to make a hole?
2463 	 */
2464 	if (start_d < ichdr_d->count) {
2465 		tmp  = ichdr_d->count - start_d;
2466 		tmp *= sizeof(xfs_attr_leaf_entry_t);
2467 		entry_s = &xfs_attr3_leaf_entryp(leaf_d)[start_d];
2468 		entry_d = &xfs_attr3_leaf_entryp(leaf_d)[start_d + count];
2469 		memmove(entry_d, entry_s, tmp);
2470 	}
2471 
2472 	/*
2473 	 * Copy all entry's in the same (sorted) order,
2474 	 * but allocate attribute info packed and in sequence.
2475 	 */
2476 	entry_s = &xfs_attr3_leaf_entryp(leaf_s)[start_s];
2477 	entry_d = &xfs_attr3_leaf_entryp(leaf_d)[start_d];
2478 	desti = start_d;
2479 	for (i = 0; i < count; entry_s++, entry_d++, desti++, i++) {
2480 		ASSERT(be16_to_cpu(entry_s->nameidx) >= ichdr_s->firstused);
2481 		tmp = xfs_attr_leaf_entsize(leaf_s, start_s + i);
2482 #ifdef GROT
2483 		/*
2484 		 * Code to drop INCOMPLETE entries.  Difficult to use as we
2485 		 * may also need to change the insertion index.  Code turned
2486 		 * off for 6.2, should be revisited later.
2487 		 */
2488 		if (entry_s->flags & XFS_ATTR_INCOMPLETE) { /* skip partials? */
2489 			memset(xfs_attr3_leaf_name(leaf_s, start_s + i), 0, tmp);
2490 			ichdr_s->usedbytes -= tmp;
2491 			ichdr_s->count -= 1;
2492 			entry_d--;	/* to compensate for ++ in loop hdr */
2493 			desti--;
2494 			if ((start_s + i) < offset)
2495 				result++;	/* insertion index adjustment */
2496 		} else {
2497 #endif /* GROT */
2498 			ichdr_d->firstused -= tmp;
2499 			/* both on-disk, don't endian flip twice */
2500 			entry_d->hashval = entry_s->hashval;
2501 			entry_d->nameidx = cpu_to_be16(ichdr_d->firstused);
2502 			entry_d->flags = entry_s->flags;
2503 			ASSERT(be16_to_cpu(entry_d->nameidx) + tmp
2504 							<= args->geo->blksize);
2505 			memmove(xfs_attr3_leaf_name(leaf_d, desti),
2506 				xfs_attr3_leaf_name(leaf_s, start_s + i), tmp);
2507 			ASSERT(be16_to_cpu(entry_s->nameidx) + tmp
2508 							<= args->geo->blksize);
2509 			memset(xfs_attr3_leaf_name(leaf_s, start_s + i), 0, tmp);
2510 			ichdr_s->usedbytes -= tmp;
2511 			ichdr_d->usedbytes += tmp;
2512 			ichdr_s->count -= 1;
2513 			ichdr_d->count += 1;
2514 			tmp = ichdr_d->count * sizeof(xfs_attr_leaf_entry_t)
2515 					+ xfs_attr3_leaf_hdr_size(leaf_d);
2516 			ASSERT(ichdr_d->firstused >= tmp);
2517 #ifdef GROT
2518 		}
2519 #endif /* GROT */
2520 	}
2521 
2522 	/*
2523 	 * Zero out the entries we just copied.
2524 	 */
2525 	if (start_s == ichdr_s->count) {
2526 		tmp = count * sizeof(xfs_attr_leaf_entry_t);
2527 		entry_s = &xfs_attr3_leaf_entryp(leaf_s)[start_s];
2528 		ASSERT(((char *)entry_s + tmp) <=
2529 		       ((char *)leaf_s + args->geo->blksize));
2530 		memset(entry_s, 0, tmp);
2531 	} else {
2532 		/*
2533 		 * Move the remaining entries down to fill the hole,
2534 		 * then zero the entries at the top.
2535 		 */
2536 		tmp  = (ichdr_s->count - count) * sizeof(xfs_attr_leaf_entry_t);
2537 		entry_s = &xfs_attr3_leaf_entryp(leaf_s)[start_s + count];
2538 		entry_d = &xfs_attr3_leaf_entryp(leaf_s)[start_s];
2539 		memmove(entry_d, entry_s, tmp);
2540 
2541 		tmp = count * sizeof(xfs_attr_leaf_entry_t);
2542 		entry_s = &xfs_attr3_leaf_entryp(leaf_s)[ichdr_s->count];
2543 		ASSERT(((char *)entry_s + tmp) <=
2544 		       ((char *)leaf_s + args->geo->blksize));
2545 		memset(entry_s, 0, tmp);
2546 	}
2547 
2548 	/*
2549 	 * Fill in the freemap information
2550 	 */
2551 	ichdr_d->freemap[0].base = xfs_attr3_leaf_hdr_size(leaf_d);
2552 	ichdr_d->freemap[0].base += ichdr_d->count * sizeof(xfs_attr_leaf_entry_t);
2553 	ichdr_d->freemap[0].size = ichdr_d->firstused - ichdr_d->freemap[0].base;
2554 	ichdr_d->freemap[1].base = 0;
2555 	ichdr_d->freemap[2].base = 0;
2556 	ichdr_d->freemap[1].size = 0;
2557 	ichdr_d->freemap[2].size = 0;
2558 	ichdr_s->holes = 1;	/* leaf may not be compact */
2559 }
2560 
2561 /*
2562  * Pick up the last hashvalue from a leaf block.
2563  */
2564 xfs_dahash_t
2565 xfs_attr_leaf_lasthash(
2566 	struct xfs_buf	*bp,
2567 	int		*count)
2568 {
2569 	struct xfs_attr3_icleaf_hdr ichdr;
2570 	struct xfs_attr_leaf_entry *entries;
2571 	struct xfs_mount *mp = bp->b_target->bt_mount;
2572 
2573 	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, bp->b_addr);
2574 	entries = xfs_attr3_leaf_entryp(bp->b_addr);
2575 	if (count)
2576 		*count = ichdr.count;
2577 	if (!ichdr.count)
2578 		return 0;
2579 	return be32_to_cpu(entries[ichdr.count - 1].hashval);
2580 }
2581 
2582 /*
2583  * Calculate the number of bytes used to store the indicated attribute
2584  * (whether local or remote only calculate bytes in this block).
2585  */
2586 STATIC int
2587 xfs_attr_leaf_entsize(xfs_attr_leafblock_t *leaf, int index)
2588 {
2589 	struct xfs_attr_leaf_entry *entries;
2590 	xfs_attr_leaf_name_local_t *name_loc;
2591 	xfs_attr_leaf_name_remote_t *name_rmt;
2592 	int size;
2593 
2594 	entries = xfs_attr3_leaf_entryp(leaf);
2595 	if (entries[index].flags & XFS_ATTR_LOCAL) {
2596 		name_loc = xfs_attr3_leaf_name_local(leaf, index);
2597 		size = xfs_attr_leaf_entsize_local(name_loc->namelen,
2598 						   be16_to_cpu(name_loc->valuelen));
2599 	} else {
2600 		name_rmt = xfs_attr3_leaf_name_remote(leaf, index);
2601 		size = xfs_attr_leaf_entsize_remote(name_rmt->namelen);
2602 	}
2603 	return size;
2604 }
2605 
2606 /*
2607  * Calculate the number of bytes that would be required to store the new
2608  * attribute (whether local or remote only calculate bytes in this block).
2609  * This routine decides as a side effect whether the attribute will be
2610  * a "local" or a "remote" attribute.
2611  */
2612 int
2613 xfs_attr_leaf_newentsize(
2614 	struct xfs_da_args	*args,
2615 	int			*local)
2616 {
2617 	int			size;
2618 
2619 	size = xfs_attr_leaf_entsize_local(args->namelen, args->valuelen);
2620 	if (size < xfs_attr_leaf_entsize_local_max(args->geo->blksize)) {
2621 		if (local)
2622 			*local = 1;
2623 		return size;
2624 	}
2625 	if (local)
2626 		*local = 0;
2627 	return xfs_attr_leaf_entsize_remote(args->namelen);
2628 }
2629 
2630 
2631 /*========================================================================
2632  * Manage the INCOMPLETE flag in a leaf entry
2633  *========================================================================*/
2634 
2635 /*
2636  * Clear the INCOMPLETE flag on an entry in a leaf block.
2637  */
2638 int
2639 xfs_attr3_leaf_clearflag(
2640 	struct xfs_da_args	*args)
2641 {
2642 	struct xfs_attr_leafblock *leaf;
2643 	struct xfs_attr_leaf_entry *entry;
2644 	struct xfs_attr_leaf_name_remote *name_rmt;
2645 	struct xfs_buf		*bp;
2646 	int			error;
2647 #ifdef DEBUG
2648 	struct xfs_attr3_icleaf_hdr ichdr;
2649 	xfs_attr_leaf_name_local_t *name_loc;
2650 	int namelen;
2651 	char *name;
2652 #endif /* DEBUG */
2653 
2654 	trace_xfs_attr_leaf_clearflag(args);
2655 	/*
2656 	 * Set up the operation.
2657 	 */
2658 	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
2659 	if (error)
2660 		return error;
2661 
2662 	leaf = bp->b_addr;
2663 	entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
2664 	ASSERT(entry->flags & XFS_ATTR_INCOMPLETE);
2665 
2666 #ifdef DEBUG
2667 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
2668 	ASSERT(args->index < ichdr.count);
2669 	ASSERT(args->index >= 0);
2670 
2671 	if (entry->flags & XFS_ATTR_LOCAL) {
2672 		name_loc = xfs_attr3_leaf_name_local(leaf, args->index);
2673 		namelen = name_loc->namelen;
2674 		name = (char *)name_loc->nameval;
2675 	} else {
2676 		name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
2677 		namelen = name_rmt->namelen;
2678 		name = (char *)name_rmt->name;
2679 	}
2680 	ASSERT(be32_to_cpu(entry->hashval) == args->hashval);
2681 	ASSERT(namelen == args->namelen);
2682 	ASSERT(memcmp(name, args->name, namelen) == 0);
2683 #endif /* DEBUG */
2684 
2685 	entry->flags &= ~XFS_ATTR_INCOMPLETE;
2686 	xfs_trans_log_buf(args->trans, bp,
2687 			 XFS_DA_LOGRANGE(leaf, entry, sizeof(*entry)));
2688 
2689 	if (args->rmtblkno) {
2690 		ASSERT((entry->flags & XFS_ATTR_LOCAL) == 0);
2691 		name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
2692 		name_rmt->valueblk = cpu_to_be32(args->rmtblkno);
2693 		name_rmt->valuelen = cpu_to_be32(args->rmtvaluelen);
2694 		xfs_trans_log_buf(args->trans, bp,
2695 			 XFS_DA_LOGRANGE(leaf, name_rmt, sizeof(*name_rmt)));
2696 	}
2697 
2698 	/*
2699 	 * Commit the flag value change and start the next trans in series.
2700 	 */
2701 	return xfs_trans_roll_inode(&args->trans, args->dp);
2702 }
2703 
2704 /*
2705  * Set the INCOMPLETE flag on an entry in a leaf block.
2706  */
2707 int
2708 xfs_attr3_leaf_setflag(
2709 	struct xfs_da_args	*args)
2710 {
2711 	struct xfs_attr_leafblock *leaf;
2712 	struct xfs_attr_leaf_entry *entry;
2713 	struct xfs_attr_leaf_name_remote *name_rmt;
2714 	struct xfs_buf		*bp;
2715 	int error;
2716 #ifdef DEBUG
2717 	struct xfs_attr3_icleaf_hdr ichdr;
2718 #endif
2719 
2720 	trace_xfs_attr_leaf_setflag(args);
2721 
2722 	/*
2723 	 * Set up the operation.
2724 	 */
2725 	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
2726 	if (error)
2727 		return error;
2728 
2729 	leaf = bp->b_addr;
2730 #ifdef DEBUG
2731 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
2732 	ASSERT(args->index < ichdr.count);
2733 	ASSERT(args->index >= 0);
2734 #endif
2735 	entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
2736 
2737 	ASSERT((entry->flags & XFS_ATTR_INCOMPLETE) == 0);
2738 	entry->flags |= XFS_ATTR_INCOMPLETE;
2739 	xfs_trans_log_buf(args->trans, bp,
2740 			XFS_DA_LOGRANGE(leaf, entry, sizeof(*entry)));
2741 	if ((entry->flags & XFS_ATTR_LOCAL) == 0) {
2742 		name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
2743 		name_rmt->valueblk = 0;
2744 		name_rmt->valuelen = 0;
2745 		xfs_trans_log_buf(args->trans, bp,
2746 			 XFS_DA_LOGRANGE(leaf, name_rmt, sizeof(*name_rmt)));
2747 	}
2748 
2749 	/*
2750 	 * Commit the flag value change and start the next trans in series.
2751 	 */
2752 	return xfs_trans_roll_inode(&args->trans, args->dp);
2753 }
2754 
2755 /*
2756  * In a single transaction, clear the INCOMPLETE flag on the leaf entry
2757  * given by args->blkno/index and set the INCOMPLETE flag on the leaf
2758  * entry given by args->blkno2/index2.
2759  *
2760  * Note that they could be in different blocks, or in the same block.
2761  */
2762 int
2763 xfs_attr3_leaf_flipflags(
2764 	struct xfs_da_args	*args)
2765 {
2766 	struct xfs_attr_leafblock *leaf1;
2767 	struct xfs_attr_leafblock *leaf2;
2768 	struct xfs_attr_leaf_entry *entry1;
2769 	struct xfs_attr_leaf_entry *entry2;
2770 	struct xfs_attr_leaf_name_remote *name_rmt;
2771 	struct xfs_buf		*bp1;
2772 	struct xfs_buf		*bp2;
2773 	int error;
2774 #ifdef DEBUG
2775 	struct xfs_attr3_icleaf_hdr ichdr1;
2776 	struct xfs_attr3_icleaf_hdr ichdr2;
2777 	xfs_attr_leaf_name_local_t *name_loc;
2778 	int namelen1, namelen2;
2779 	char *name1, *name2;
2780 #endif /* DEBUG */
2781 
2782 	trace_xfs_attr_leaf_flipflags(args);
2783 
2784 	/*
2785 	 * Read the block containing the "old" attr
2786 	 */
2787 	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp1);
2788 	if (error)
2789 		return error;
2790 
2791 	/*
2792 	 * Read the block containing the "new" attr, if it is different
2793 	 */
2794 	if (args->blkno2 != args->blkno) {
2795 		error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno2,
2796 					   -1, &bp2);
2797 		if (error)
2798 			return error;
2799 	} else {
2800 		bp2 = bp1;
2801 	}
2802 
2803 	leaf1 = bp1->b_addr;
2804 	entry1 = &xfs_attr3_leaf_entryp(leaf1)[args->index];
2805 
2806 	leaf2 = bp2->b_addr;
2807 	entry2 = &xfs_attr3_leaf_entryp(leaf2)[args->index2];
2808 
2809 #ifdef DEBUG
2810 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr1, leaf1);
2811 	ASSERT(args->index < ichdr1.count);
2812 	ASSERT(args->index >= 0);
2813 
2814 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr2, leaf2);
2815 	ASSERT(args->index2 < ichdr2.count);
2816 	ASSERT(args->index2 >= 0);
2817 
2818 	if (entry1->flags & XFS_ATTR_LOCAL) {
2819 		name_loc = xfs_attr3_leaf_name_local(leaf1, args->index);
2820 		namelen1 = name_loc->namelen;
2821 		name1 = (char *)name_loc->nameval;
2822 	} else {
2823 		name_rmt = xfs_attr3_leaf_name_remote(leaf1, args->index);
2824 		namelen1 = name_rmt->namelen;
2825 		name1 = (char *)name_rmt->name;
2826 	}
2827 	if (entry2->flags & XFS_ATTR_LOCAL) {
2828 		name_loc = xfs_attr3_leaf_name_local(leaf2, args->index2);
2829 		namelen2 = name_loc->namelen;
2830 		name2 = (char *)name_loc->nameval;
2831 	} else {
2832 		name_rmt = xfs_attr3_leaf_name_remote(leaf2, args->index2);
2833 		namelen2 = name_rmt->namelen;
2834 		name2 = (char *)name_rmt->name;
2835 	}
2836 	ASSERT(be32_to_cpu(entry1->hashval) == be32_to_cpu(entry2->hashval));
2837 	ASSERT(namelen1 == namelen2);
2838 	ASSERT(memcmp(name1, name2, namelen1) == 0);
2839 #endif /* DEBUG */
2840 
2841 	ASSERT(entry1->flags & XFS_ATTR_INCOMPLETE);
2842 	ASSERT((entry2->flags & XFS_ATTR_INCOMPLETE) == 0);
2843 
2844 	entry1->flags &= ~XFS_ATTR_INCOMPLETE;
2845 	xfs_trans_log_buf(args->trans, bp1,
2846 			  XFS_DA_LOGRANGE(leaf1, entry1, sizeof(*entry1)));
2847 	if (args->rmtblkno) {
2848 		ASSERT((entry1->flags & XFS_ATTR_LOCAL) == 0);
2849 		name_rmt = xfs_attr3_leaf_name_remote(leaf1, args->index);
2850 		name_rmt->valueblk = cpu_to_be32(args->rmtblkno);
2851 		name_rmt->valuelen = cpu_to_be32(args->rmtvaluelen);
2852 		xfs_trans_log_buf(args->trans, bp1,
2853 			 XFS_DA_LOGRANGE(leaf1, name_rmt, sizeof(*name_rmt)));
2854 	}
2855 
2856 	entry2->flags |= XFS_ATTR_INCOMPLETE;
2857 	xfs_trans_log_buf(args->trans, bp2,
2858 			  XFS_DA_LOGRANGE(leaf2, entry2, sizeof(*entry2)));
2859 	if ((entry2->flags & XFS_ATTR_LOCAL) == 0) {
2860 		name_rmt = xfs_attr3_leaf_name_remote(leaf2, args->index2);
2861 		name_rmt->valueblk = 0;
2862 		name_rmt->valuelen = 0;
2863 		xfs_trans_log_buf(args->trans, bp2,
2864 			 XFS_DA_LOGRANGE(leaf2, name_rmt, sizeof(*name_rmt)));
2865 	}
2866 
2867 	/*
2868 	 * Commit the flag value change and start the next trans in series.
2869 	 */
2870 	error = xfs_trans_roll_inode(&args->trans, args->dp);
2871 
2872 	return error;
2873 }
2874