xref: /linux/fs/xfs/libxfs/xfs_attr_leaf.c (revision 3932b9ca55b0be314a36d3e84faff3e823c081f5)
1 /*
2  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
3  * Copyright (c) 2013 Red Hat, Inc.
4  * All Rights Reserved.
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License as
8  * published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it would be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write the Free Software Foundation,
17  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
18  */
19 #include "xfs.h"
20 #include "xfs_fs.h"
21 #include "xfs_shared.h"
22 #include "xfs_format.h"
23 #include "xfs_log_format.h"
24 #include "xfs_trans_resv.h"
25 #include "xfs_bit.h"
26 #include "xfs_sb.h"
27 #include "xfs_ag.h"
28 #include "xfs_mount.h"
29 #include "xfs_da_format.h"
30 #include "xfs_da_btree.h"
31 #include "xfs_inode.h"
32 #include "xfs_trans.h"
33 #include "xfs_inode_item.h"
34 #include "xfs_bmap_btree.h"
35 #include "xfs_bmap.h"
36 #include "xfs_attr_sf.h"
37 #include "xfs_attr_remote.h"
38 #include "xfs_attr.h"
39 #include "xfs_attr_leaf.h"
40 #include "xfs_error.h"
41 #include "xfs_trace.h"
42 #include "xfs_buf_item.h"
43 #include "xfs_cksum.h"
44 #include "xfs_dinode.h"
45 #include "xfs_dir2.h"
46 
47 
48 /*
49  * xfs_attr_leaf.c
50  *
51  * Routines to implement leaf blocks of attributes as Btrees of hashed names.
52  */
53 
54 /*========================================================================
55  * Function prototypes for the kernel.
56  *========================================================================*/
57 
58 /*
59  * Routines used for growing the Btree.
60  */
61 STATIC int xfs_attr3_leaf_create(struct xfs_da_args *args,
62 				 xfs_dablk_t which_block, struct xfs_buf **bpp);
63 STATIC int xfs_attr3_leaf_add_work(struct xfs_buf *leaf_buffer,
64 				   struct xfs_attr3_icleaf_hdr *ichdr,
65 				   struct xfs_da_args *args, int freemap_index);
66 STATIC void xfs_attr3_leaf_compact(struct xfs_da_args *args,
67 				   struct xfs_attr3_icleaf_hdr *ichdr,
68 				   struct xfs_buf *leaf_buffer);
69 STATIC void xfs_attr3_leaf_rebalance(xfs_da_state_t *state,
70 						   xfs_da_state_blk_t *blk1,
71 						   xfs_da_state_blk_t *blk2);
72 STATIC int xfs_attr3_leaf_figure_balance(xfs_da_state_t *state,
73 			xfs_da_state_blk_t *leaf_blk_1,
74 			struct xfs_attr3_icleaf_hdr *ichdr1,
75 			xfs_da_state_blk_t *leaf_blk_2,
76 			struct xfs_attr3_icleaf_hdr *ichdr2,
77 			int *number_entries_in_blk1,
78 			int *number_usedbytes_in_blk1);
79 
80 /*
81  * Utility routines.
82  */
83 STATIC void xfs_attr3_leaf_moveents(struct xfs_da_args *args,
84 			struct xfs_attr_leafblock *src_leaf,
85 			struct xfs_attr3_icleaf_hdr *src_ichdr, int src_start,
86 			struct xfs_attr_leafblock *dst_leaf,
87 			struct xfs_attr3_icleaf_hdr *dst_ichdr, int dst_start,
88 			int move_count);
89 STATIC int xfs_attr_leaf_entsize(xfs_attr_leafblock_t *leaf, int index);
90 
91 void
92 xfs_attr3_leaf_hdr_from_disk(
93 	struct xfs_attr3_icleaf_hdr	*to,
94 	struct xfs_attr_leafblock	*from)
95 {
96 	int	i;
97 
98 	ASSERT(from->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC) ||
99 	       from->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC));
100 
101 	if (from->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC)) {
102 		struct xfs_attr3_leaf_hdr *hdr3 = (struct xfs_attr3_leaf_hdr *)from;
103 
104 		to->forw = be32_to_cpu(hdr3->info.hdr.forw);
105 		to->back = be32_to_cpu(hdr3->info.hdr.back);
106 		to->magic = be16_to_cpu(hdr3->info.hdr.magic);
107 		to->count = be16_to_cpu(hdr3->count);
108 		to->usedbytes = be16_to_cpu(hdr3->usedbytes);
109 		to->firstused = be16_to_cpu(hdr3->firstused);
110 		to->holes = hdr3->holes;
111 
112 		for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
113 			to->freemap[i].base = be16_to_cpu(hdr3->freemap[i].base);
114 			to->freemap[i].size = be16_to_cpu(hdr3->freemap[i].size);
115 		}
116 		return;
117 	}
118 	to->forw = be32_to_cpu(from->hdr.info.forw);
119 	to->back = be32_to_cpu(from->hdr.info.back);
120 	to->magic = be16_to_cpu(from->hdr.info.magic);
121 	to->count = be16_to_cpu(from->hdr.count);
122 	to->usedbytes = be16_to_cpu(from->hdr.usedbytes);
123 	to->firstused = be16_to_cpu(from->hdr.firstused);
124 	to->holes = from->hdr.holes;
125 
126 	for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
127 		to->freemap[i].base = be16_to_cpu(from->hdr.freemap[i].base);
128 		to->freemap[i].size = be16_to_cpu(from->hdr.freemap[i].size);
129 	}
130 }
131 
132 void
133 xfs_attr3_leaf_hdr_to_disk(
134 	struct xfs_attr_leafblock	*to,
135 	struct xfs_attr3_icleaf_hdr	*from)
136 {
137 	int	i;
138 
139 	ASSERT(from->magic == XFS_ATTR_LEAF_MAGIC ||
140 	       from->magic == XFS_ATTR3_LEAF_MAGIC);
141 
142 	if (from->magic == XFS_ATTR3_LEAF_MAGIC) {
143 		struct xfs_attr3_leaf_hdr *hdr3 = (struct xfs_attr3_leaf_hdr *)to;
144 
145 		hdr3->info.hdr.forw = cpu_to_be32(from->forw);
146 		hdr3->info.hdr.back = cpu_to_be32(from->back);
147 		hdr3->info.hdr.magic = cpu_to_be16(from->magic);
148 		hdr3->count = cpu_to_be16(from->count);
149 		hdr3->usedbytes = cpu_to_be16(from->usedbytes);
150 		hdr3->firstused = cpu_to_be16(from->firstused);
151 		hdr3->holes = from->holes;
152 		hdr3->pad1 = 0;
153 
154 		for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
155 			hdr3->freemap[i].base = cpu_to_be16(from->freemap[i].base);
156 			hdr3->freemap[i].size = cpu_to_be16(from->freemap[i].size);
157 		}
158 		return;
159 	}
160 	to->hdr.info.forw = cpu_to_be32(from->forw);
161 	to->hdr.info.back = cpu_to_be32(from->back);
162 	to->hdr.info.magic = cpu_to_be16(from->magic);
163 	to->hdr.count = cpu_to_be16(from->count);
164 	to->hdr.usedbytes = cpu_to_be16(from->usedbytes);
165 	to->hdr.firstused = cpu_to_be16(from->firstused);
166 	to->hdr.holes = from->holes;
167 	to->hdr.pad1 = 0;
168 
169 	for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
170 		to->hdr.freemap[i].base = cpu_to_be16(from->freemap[i].base);
171 		to->hdr.freemap[i].size = cpu_to_be16(from->freemap[i].size);
172 	}
173 }
174 
175 static bool
176 xfs_attr3_leaf_verify(
177 	struct xfs_buf		*bp)
178 {
179 	struct xfs_mount	*mp = bp->b_target->bt_mount;
180 	struct xfs_attr_leafblock *leaf = bp->b_addr;
181 	struct xfs_attr3_icleaf_hdr ichdr;
182 
183 	xfs_attr3_leaf_hdr_from_disk(&ichdr, leaf);
184 
185 	if (xfs_sb_version_hascrc(&mp->m_sb)) {
186 		struct xfs_da3_node_hdr *hdr3 = bp->b_addr;
187 
188 		if (ichdr.magic != XFS_ATTR3_LEAF_MAGIC)
189 			return false;
190 
191 		if (!uuid_equal(&hdr3->info.uuid, &mp->m_sb.sb_uuid))
192 			return false;
193 		if (be64_to_cpu(hdr3->info.blkno) != bp->b_bn)
194 			return false;
195 	} else {
196 		if (ichdr.magic != XFS_ATTR_LEAF_MAGIC)
197 			return false;
198 	}
199 	if (ichdr.count == 0)
200 		return false;
201 
202 	/* XXX: need to range check rest of attr header values */
203 	/* XXX: hash order check? */
204 
205 	return true;
206 }
207 
208 static void
209 xfs_attr3_leaf_write_verify(
210 	struct xfs_buf	*bp)
211 {
212 	struct xfs_mount	*mp = bp->b_target->bt_mount;
213 	struct xfs_buf_log_item	*bip = bp->b_fspriv;
214 	struct xfs_attr3_leaf_hdr *hdr3 = bp->b_addr;
215 
216 	if (!xfs_attr3_leaf_verify(bp)) {
217 		xfs_buf_ioerror(bp, -EFSCORRUPTED);
218 		xfs_verifier_error(bp);
219 		return;
220 	}
221 
222 	if (!xfs_sb_version_hascrc(&mp->m_sb))
223 		return;
224 
225 	if (bip)
226 		hdr3->info.lsn = cpu_to_be64(bip->bli_item.li_lsn);
227 
228 	xfs_buf_update_cksum(bp, XFS_ATTR3_LEAF_CRC_OFF);
229 }
230 
231 /*
232  * leaf/node format detection on trees is sketchy, so a node read can be done on
233  * leaf level blocks when detection identifies the tree as a node format tree
234  * incorrectly. In this case, we need to swap the verifier to match the correct
235  * format of the block being read.
236  */
237 static void
238 xfs_attr3_leaf_read_verify(
239 	struct xfs_buf		*bp)
240 {
241 	struct xfs_mount	*mp = bp->b_target->bt_mount;
242 
243 	if (xfs_sb_version_hascrc(&mp->m_sb) &&
244 	     !xfs_buf_verify_cksum(bp, XFS_ATTR3_LEAF_CRC_OFF))
245 		xfs_buf_ioerror(bp, -EFSBADCRC);
246 	else if (!xfs_attr3_leaf_verify(bp))
247 		xfs_buf_ioerror(bp, -EFSCORRUPTED);
248 
249 	if (bp->b_error)
250 		xfs_verifier_error(bp);
251 }
252 
253 const struct xfs_buf_ops xfs_attr3_leaf_buf_ops = {
254 	.verify_read = xfs_attr3_leaf_read_verify,
255 	.verify_write = xfs_attr3_leaf_write_verify,
256 };
257 
258 int
259 xfs_attr3_leaf_read(
260 	struct xfs_trans	*tp,
261 	struct xfs_inode	*dp,
262 	xfs_dablk_t		bno,
263 	xfs_daddr_t		mappedbno,
264 	struct xfs_buf		**bpp)
265 {
266 	int			err;
267 
268 	err = xfs_da_read_buf(tp, dp, bno, mappedbno, bpp,
269 				XFS_ATTR_FORK, &xfs_attr3_leaf_buf_ops);
270 	if (!err && tp)
271 		xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_ATTR_LEAF_BUF);
272 	return err;
273 }
274 
275 /*========================================================================
276  * Namespace helper routines
277  *========================================================================*/
278 
279 /*
280  * If namespace bits don't match return 0.
281  * If all match then return 1.
282  */
283 STATIC int
284 xfs_attr_namesp_match(int arg_flags, int ondisk_flags)
285 {
286 	return XFS_ATTR_NSP_ONDISK(ondisk_flags) == XFS_ATTR_NSP_ARGS_TO_ONDISK(arg_flags);
287 }
288 
289 
290 /*========================================================================
291  * External routines when attribute fork size < XFS_LITINO(mp).
292  *========================================================================*/
293 
294 /*
295  * Query whether the requested number of additional bytes of extended
296  * attribute space will be able to fit inline.
297  *
298  * Returns zero if not, else the di_forkoff fork offset to be used in the
299  * literal area for attribute data once the new bytes have been added.
300  *
301  * di_forkoff must be 8 byte aligned, hence is stored as a >>3 value;
302  * special case for dev/uuid inodes, they have fixed size data forks.
303  */
304 int
305 xfs_attr_shortform_bytesfit(xfs_inode_t *dp, int bytes)
306 {
307 	int offset;
308 	int minforkoff;	/* lower limit on valid forkoff locations */
309 	int maxforkoff;	/* upper limit on valid forkoff locations */
310 	int dsize;
311 	xfs_mount_t *mp = dp->i_mount;
312 
313 	/* rounded down */
314 	offset = (XFS_LITINO(mp, dp->i_d.di_version) - bytes) >> 3;
315 
316 	switch (dp->i_d.di_format) {
317 	case XFS_DINODE_FMT_DEV:
318 		minforkoff = roundup(sizeof(xfs_dev_t), 8) >> 3;
319 		return (offset >= minforkoff) ? minforkoff : 0;
320 	case XFS_DINODE_FMT_UUID:
321 		minforkoff = roundup(sizeof(uuid_t), 8) >> 3;
322 		return (offset >= minforkoff) ? minforkoff : 0;
323 	}
324 
325 	/*
326 	 * If the requested numbers of bytes is smaller or equal to the
327 	 * current attribute fork size we can always proceed.
328 	 *
329 	 * Note that if_bytes in the data fork might actually be larger than
330 	 * the current data fork size is due to delalloc extents. In that
331 	 * case either the extent count will go down when they are converted
332 	 * to real extents, or the delalloc conversion will take care of the
333 	 * literal area rebalancing.
334 	 */
335 	if (bytes <= XFS_IFORK_ASIZE(dp))
336 		return dp->i_d.di_forkoff;
337 
338 	/*
339 	 * For attr2 we can try to move the forkoff if there is space in the
340 	 * literal area, but for the old format we are done if there is no
341 	 * space in the fixed attribute fork.
342 	 */
343 	if (!(mp->m_flags & XFS_MOUNT_ATTR2))
344 		return 0;
345 
346 	dsize = dp->i_df.if_bytes;
347 
348 	switch (dp->i_d.di_format) {
349 	case XFS_DINODE_FMT_EXTENTS:
350 		/*
351 		 * If there is no attr fork and the data fork is extents,
352 		 * determine if creating the default attr fork will result
353 		 * in the extents form migrating to btree. If so, the
354 		 * minimum offset only needs to be the space required for
355 		 * the btree root.
356 		 */
357 		if (!dp->i_d.di_forkoff && dp->i_df.if_bytes >
358 		    xfs_default_attroffset(dp))
359 			dsize = XFS_BMDR_SPACE_CALC(MINDBTPTRS);
360 		break;
361 	case XFS_DINODE_FMT_BTREE:
362 		/*
363 		 * If we have a data btree then keep forkoff if we have one,
364 		 * otherwise we are adding a new attr, so then we set
365 		 * minforkoff to where the btree root can finish so we have
366 		 * plenty of room for attrs
367 		 */
368 		if (dp->i_d.di_forkoff) {
369 			if (offset < dp->i_d.di_forkoff)
370 				return 0;
371 			return dp->i_d.di_forkoff;
372 		}
373 		dsize = XFS_BMAP_BROOT_SPACE(mp, dp->i_df.if_broot);
374 		break;
375 	}
376 
377 	/*
378 	 * A data fork btree root must have space for at least
379 	 * MINDBTPTRS key/ptr pairs if the data fork is small or empty.
380 	 */
381 	minforkoff = MAX(dsize, XFS_BMDR_SPACE_CALC(MINDBTPTRS));
382 	minforkoff = roundup(minforkoff, 8) >> 3;
383 
384 	/* attr fork btree root can have at least this many key/ptr pairs */
385 	maxforkoff = XFS_LITINO(mp, dp->i_d.di_version) -
386 			XFS_BMDR_SPACE_CALC(MINABTPTRS);
387 	maxforkoff = maxforkoff >> 3;	/* rounded down */
388 
389 	if (offset >= maxforkoff)
390 		return maxforkoff;
391 	if (offset >= minforkoff)
392 		return offset;
393 	return 0;
394 }
395 
396 /*
397  * Switch on the ATTR2 superblock bit (implies also FEATURES2)
398  */
399 STATIC void
400 xfs_sbversion_add_attr2(xfs_mount_t *mp, xfs_trans_t *tp)
401 {
402 	if ((mp->m_flags & XFS_MOUNT_ATTR2) &&
403 	    !(xfs_sb_version_hasattr2(&mp->m_sb))) {
404 		spin_lock(&mp->m_sb_lock);
405 		if (!xfs_sb_version_hasattr2(&mp->m_sb)) {
406 			xfs_sb_version_addattr2(&mp->m_sb);
407 			spin_unlock(&mp->m_sb_lock);
408 			xfs_mod_sb(tp, XFS_SB_VERSIONNUM | XFS_SB_FEATURES2);
409 		} else
410 			spin_unlock(&mp->m_sb_lock);
411 	}
412 }
413 
414 /*
415  * Create the initial contents of a shortform attribute list.
416  */
417 void
418 xfs_attr_shortform_create(xfs_da_args_t *args)
419 {
420 	xfs_attr_sf_hdr_t *hdr;
421 	xfs_inode_t *dp;
422 	xfs_ifork_t *ifp;
423 
424 	trace_xfs_attr_sf_create(args);
425 
426 	dp = args->dp;
427 	ASSERT(dp != NULL);
428 	ifp = dp->i_afp;
429 	ASSERT(ifp != NULL);
430 	ASSERT(ifp->if_bytes == 0);
431 	if (dp->i_d.di_aformat == XFS_DINODE_FMT_EXTENTS) {
432 		ifp->if_flags &= ~XFS_IFEXTENTS;	/* just in case */
433 		dp->i_d.di_aformat = XFS_DINODE_FMT_LOCAL;
434 		ifp->if_flags |= XFS_IFINLINE;
435 	} else {
436 		ASSERT(ifp->if_flags & XFS_IFINLINE);
437 	}
438 	xfs_idata_realloc(dp, sizeof(*hdr), XFS_ATTR_FORK);
439 	hdr = (xfs_attr_sf_hdr_t *)ifp->if_u1.if_data;
440 	hdr->count = 0;
441 	hdr->totsize = cpu_to_be16(sizeof(*hdr));
442 	xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE | XFS_ILOG_ADATA);
443 }
444 
445 /*
446  * Add a name/value pair to the shortform attribute list.
447  * Overflow from the inode has already been checked for.
448  */
449 void
450 xfs_attr_shortform_add(xfs_da_args_t *args, int forkoff)
451 {
452 	xfs_attr_shortform_t *sf;
453 	xfs_attr_sf_entry_t *sfe;
454 	int i, offset, size;
455 	xfs_mount_t *mp;
456 	xfs_inode_t *dp;
457 	xfs_ifork_t *ifp;
458 
459 	trace_xfs_attr_sf_add(args);
460 
461 	dp = args->dp;
462 	mp = dp->i_mount;
463 	dp->i_d.di_forkoff = forkoff;
464 
465 	ifp = dp->i_afp;
466 	ASSERT(ifp->if_flags & XFS_IFINLINE);
467 	sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
468 	sfe = &sf->list[0];
469 	for (i = 0; i < sf->hdr.count; sfe = XFS_ATTR_SF_NEXTENTRY(sfe), i++) {
470 #ifdef DEBUG
471 		if (sfe->namelen != args->namelen)
472 			continue;
473 		if (memcmp(args->name, sfe->nameval, args->namelen) != 0)
474 			continue;
475 		if (!xfs_attr_namesp_match(args->flags, sfe->flags))
476 			continue;
477 		ASSERT(0);
478 #endif
479 	}
480 
481 	offset = (char *)sfe - (char *)sf;
482 	size = XFS_ATTR_SF_ENTSIZE_BYNAME(args->namelen, args->valuelen);
483 	xfs_idata_realloc(dp, size, XFS_ATTR_FORK);
484 	sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
485 	sfe = (xfs_attr_sf_entry_t *)((char *)sf + offset);
486 
487 	sfe->namelen = args->namelen;
488 	sfe->valuelen = args->valuelen;
489 	sfe->flags = XFS_ATTR_NSP_ARGS_TO_ONDISK(args->flags);
490 	memcpy(sfe->nameval, args->name, args->namelen);
491 	memcpy(&sfe->nameval[args->namelen], args->value, args->valuelen);
492 	sf->hdr.count++;
493 	be16_add_cpu(&sf->hdr.totsize, size);
494 	xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE | XFS_ILOG_ADATA);
495 
496 	xfs_sbversion_add_attr2(mp, args->trans);
497 }
498 
499 /*
500  * After the last attribute is removed revert to original inode format,
501  * making all literal area available to the data fork once more.
502  */
503 STATIC void
504 xfs_attr_fork_reset(
505 	struct xfs_inode	*ip,
506 	struct xfs_trans	*tp)
507 {
508 	xfs_idestroy_fork(ip, XFS_ATTR_FORK);
509 	ip->i_d.di_forkoff = 0;
510 	ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
511 
512 	ASSERT(ip->i_d.di_anextents == 0);
513 	ASSERT(ip->i_afp == NULL);
514 
515 	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
516 }
517 
518 /*
519  * Remove an attribute from the shortform attribute list structure.
520  */
521 int
522 xfs_attr_shortform_remove(xfs_da_args_t *args)
523 {
524 	xfs_attr_shortform_t *sf;
525 	xfs_attr_sf_entry_t *sfe;
526 	int base, size=0, end, totsize, i;
527 	xfs_mount_t *mp;
528 	xfs_inode_t *dp;
529 
530 	trace_xfs_attr_sf_remove(args);
531 
532 	dp = args->dp;
533 	mp = dp->i_mount;
534 	base = sizeof(xfs_attr_sf_hdr_t);
535 	sf = (xfs_attr_shortform_t *)dp->i_afp->if_u1.if_data;
536 	sfe = &sf->list[0];
537 	end = sf->hdr.count;
538 	for (i = 0; i < end; sfe = XFS_ATTR_SF_NEXTENTRY(sfe),
539 					base += size, i++) {
540 		size = XFS_ATTR_SF_ENTSIZE(sfe);
541 		if (sfe->namelen != args->namelen)
542 			continue;
543 		if (memcmp(sfe->nameval, args->name, args->namelen) != 0)
544 			continue;
545 		if (!xfs_attr_namesp_match(args->flags, sfe->flags))
546 			continue;
547 		break;
548 	}
549 	if (i == end)
550 		return -ENOATTR;
551 
552 	/*
553 	 * Fix up the attribute fork data, covering the hole
554 	 */
555 	end = base + size;
556 	totsize = be16_to_cpu(sf->hdr.totsize);
557 	if (end != totsize)
558 		memmove(&((char *)sf)[base], &((char *)sf)[end], totsize - end);
559 	sf->hdr.count--;
560 	be16_add_cpu(&sf->hdr.totsize, -size);
561 
562 	/*
563 	 * Fix up the start offset of the attribute fork
564 	 */
565 	totsize -= size;
566 	if (totsize == sizeof(xfs_attr_sf_hdr_t) &&
567 	    (mp->m_flags & XFS_MOUNT_ATTR2) &&
568 	    (dp->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
569 	    !(args->op_flags & XFS_DA_OP_ADDNAME)) {
570 		xfs_attr_fork_reset(dp, args->trans);
571 	} else {
572 		xfs_idata_realloc(dp, -size, XFS_ATTR_FORK);
573 		dp->i_d.di_forkoff = xfs_attr_shortform_bytesfit(dp, totsize);
574 		ASSERT(dp->i_d.di_forkoff);
575 		ASSERT(totsize > sizeof(xfs_attr_sf_hdr_t) ||
576 				(args->op_flags & XFS_DA_OP_ADDNAME) ||
577 				!(mp->m_flags & XFS_MOUNT_ATTR2) ||
578 				dp->i_d.di_format == XFS_DINODE_FMT_BTREE);
579 		xfs_trans_log_inode(args->trans, dp,
580 					XFS_ILOG_CORE | XFS_ILOG_ADATA);
581 	}
582 
583 	xfs_sbversion_add_attr2(mp, args->trans);
584 
585 	return 0;
586 }
587 
588 /*
589  * Look up a name in a shortform attribute list structure.
590  */
591 /*ARGSUSED*/
592 int
593 xfs_attr_shortform_lookup(xfs_da_args_t *args)
594 {
595 	xfs_attr_shortform_t *sf;
596 	xfs_attr_sf_entry_t *sfe;
597 	int i;
598 	xfs_ifork_t *ifp;
599 
600 	trace_xfs_attr_sf_lookup(args);
601 
602 	ifp = args->dp->i_afp;
603 	ASSERT(ifp->if_flags & XFS_IFINLINE);
604 	sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
605 	sfe = &sf->list[0];
606 	for (i = 0; i < sf->hdr.count;
607 				sfe = XFS_ATTR_SF_NEXTENTRY(sfe), i++) {
608 		if (sfe->namelen != args->namelen)
609 			continue;
610 		if (memcmp(args->name, sfe->nameval, args->namelen) != 0)
611 			continue;
612 		if (!xfs_attr_namesp_match(args->flags, sfe->flags))
613 			continue;
614 		return -EEXIST;
615 	}
616 	return -ENOATTR;
617 }
618 
619 /*
620  * Look up a name in a shortform attribute list structure.
621  */
622 /*ARGSUSED*/
623 int
624 xfs_attr_shortform_getvalue(xfs_da_args_t *args)
625 {
626 	xfs_attr_shortform_t *sf;
627 	xfs_attr_sf_entry_t *sfe;
628 	int i;
629 
630 	ASSERT(args->dp->i_afp->if_flags == XFS_IFINLINE);
631 	sf = (xfs_attr_shortform_t *)args->dp->i_afp->if_u1.if_data;
632 	sfe = &sf->list[0];
633 	for (i = 0; i < sf->hdr.count;
634 				sfe = XFS_ATTR_SF_NEXTENTRY(sfe), i++) {
635 		if (sfe->namelen != args->namelen)
636 			continue;
637 		if (memcmp(args->name, sfe->nameval, args->namelen) != 0)
638 			continue;
639 		if (!xfs_attr_namesp_match(args->flags, sfe->flags))
640 			continue;
641 		if (args->flags & ATTR_KERNOVAL) {
642 			args->valuelen = sfe->valuelen;
643 			return -EEXIST;
644 		}
645 		if (args->valuelen < sfe->valuelen) {
646 			args->valuelen = sfe->valuelen;
647 			return -ERANGE;
648 		}
649 		args->valuelen = sfe->valuelen;
650 		memcpy(args->value, &sfe->nameval[args->namelen],
651 						    args->valuelen);
652 		return -EEXIST;
653 	}
654 	return -ENOATTR;
655 }
656 
657 /*
658  * Convert from using the shortform to the leaf.
659  */
660 int
661 xfs_attr_shortform_to_leaf(xfs_da_args_t *args)
662 {
663 	xfs_inode_t *dp;
664 	xfs_attr_shortform_t *sf;
665 	xfs_attr_sf_entry_t *sfe;
666 	xfs_da_args_t nargs;
667 	char *tmpbuffer;
668 	int error, i, size;
669 	xfs_dablk_t blkno;
670 	struct xfs_buf *bp;
671 	xfs_ifork_t *ifp;
672 
673 	trace_xfs_attr_sf_to_leaf(args);
674 
675 	dp = args->dp;
676 	ifp = dp->i_afp;
677 	sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
678 	size = be16_to_cpu(sf->hdr.totsize);
679 	tmpbuffer = kmem_alloc(size, KM_SLEEP);
680 	ASSERT(tmpbuffer != NULL);
681 	memcpy(tmpbuffer, ifp->if_u1.if_data, size);
682 	sf = (xfs_attr_shortform_t *)tmpbuffer;
683 
684 	xfs_idata_realloc(dp, -size, XFS_ATTR_FORK);
685 	xfs_bmap_local_to_extents_empty(dp, XFS_ATTR_FORK);
686 
687 	bp = NULL;
688 	error = xfs_da_grow_inode(args, &blkno);
689 	if (error) {
690 		/*
691 		 * If we hit an IO error middle of the transaction inside
692 		 * grow_inode(), we may have inconsistent data. Bail out.
693 		 */
694 		if (error == -EIO)
695 			goto out;
696 		xfs_idata_realloc(dp, size, XFS_ATTR_FORK);	/* try to put */
697 		memcpy(ifp->if_u1.if_data, tmpbuffer, size);	/* it back */
698 		goto out;
699 	}
700 
701 	ASSERT(blkno == 0);
702 	error = xfs_attr3_leaf_create(args, blkno, &bp);
703 	if (error) {
704 		error = xfs_da_shrink_inode(args, 0, bp);
705 		bp = NULL;
706 		if (error)
707 			goto out;
708 		xfs_idata_realloc(dp, size, XFS_ATTR_FORK);	/* try to put */
709 		memcpy(ifp->if_u1.if_data, tmpbuffer, size);	/* it back */
710 		goto out;
711 	}
712 
713 	memset((char *)&nargs, 0, sizeof(nargs));
714 	nargs.dp = dp;
715 	nargs.geo = args->geo;
716 	nargs.firstblock = args->firstblock;
717 	nargs.flist = args->flist;
718 	nargs.total = args->total;
719 	nargs.whichfork = XFS_ATTR_FORK;
720 	nargs.trans = args->trans;
721 	nargs.op_flags = XFS_DA_OP_OKNOENT;
722 
723 	sfe = &sf->list[0];
724 	for (i = 0; i < sf->hdr.count; i++) {
725 		nargs.name = sfe->nameval;
726 		nargs.namelen = sfe->namelen;
727 		nargs.value = &sfe->nameval[nargs.namelen];
728 		nargs.valuelen = sfe->valuelen;
729 		nargs.hashval = xfs_da_hashname(sfe->nameval,
730 						sfe->namelen);
731 		nargs.flags = XFS_ATTR_NSP_ONDISK_TO_ARGS(sfe->flags);
732 		error = xfs_attr3_leaf_lookup_int(bp, &nargs); /* set a->index */
733 		ASSERT(error == -ENOATTR);
734 		error = xfs_attr3_leaf_add(bp, &nargs);
735 		ASSERT(error != -ENOSPC);
736 		if (error)
737 			goto out;
738 		sfe = XFS_ATTR_SF_NEXTENTRY(sfe);
739 	}
740 	error = 0;
741 
742 out:
743 	kmem_free(tmpbuffer);
744 	return error;
745 }
746 
747 /*
748  * Check a leaf attribute block to see if all the entries would fit into
749  * a shortform attribute list.
750  */
751 int
752 xfs_attr_shortform_allfit(
753 	struct xfs_buf		*bp,
754 	struct xfs_inode	*dp)
755 {
756 	struct xfs_attr_leafblock *leaf;
757 	struct xfs_attr_leaf_entry *entry;
758 	xfs_attr_leaf_name_local_t *name_loc;
759 	struct xfs_attr3_icleaf_hdr leafhdr;
760 	int			bytes;
761 	int			i;
762 
763 	leaf = bp->b_addr;
764 	xfs_attr3_leaf_hdr_from_disk(&leafhdr, leaf);
765 	entry = xfs_attr3_leaf_entryp(leaf);
766 
767 	bytes = sizeof(struct xfs_attr_sf_hdr);
768 	for (i = 0; i < leafhdr.count; entry++, i++) {
769 		if (entry->flags & XFS_ATTR_INCOMPLETE)
770 			continue;		/* don't copy partial entries */
771 		if (!(entry->flags & XFS_ATTR_LOCAL))
772 			return 0;
773 		name_loc = xfs_attr3_leaf_name_local(leaf, i);
774 		if (name_loc->namelen >= XFS_ATTR_SF_ENTSIZE_MAX)
775 			return 0;
776 		if (be16_to_cpu(name_loc->valuelen) >= XFS_ATTR_SF_ENTSIZE_MAX)
777 			return 0;
778 		bytes += sizeof(struct xfs_attr_sf_entry) - 1
779 				+ name_loc->namelen
780 				+ be16_to_cpu(name_loc->valuelen);
781 	}
782 	if ((dp->i_mount->m_flags & XFS_MOUNT_ATTR2) &&
783 	    (dp->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
784 	    (bytes == sizeof(struct xfs_attr_sf_hdr)))
785 		return -1;
786 	return xfs_attr_shortform_bytesfit(dp, bytes);
787 }
788 
789 /*
790  * Convert a leaf attribute list to shortform attribute list
791  */
792 int
793 xfs_attr3_leaf_to_shortform(
794 	struct xfs_buf		*bp,
795 	struct xfs_da_args	*args,
796 	int			forkoff)
797 {
798 	struct xfs_attr_leafblock *leaf;
799 	struct xfs_attr3_icleaf_hdr ichdr;
800 	struct xfs_attr_leaf_entry *entry;
801 	struct xfs_attr_leaf_name_local *name_loc;
802 	struct xfs_da_args	nargs;
803 	struct xfs_inode	*dp = args->dp;
804 	char			*tmpbuffer;
805 	int			error;
806 	int			i;
807 
808 	trace_xfs_attr_leaf_to_sf(args);
809 
810 	tmpbuffer = kmem_alloc(args->geo->blksize, KM_SLEEP);
811 	if (!tmpbuffer)
812 		return -ENOMEM;
813 
814 	memcpy(tmpbuffer, bp->b_addr, args->geo->blksize);
815 
816 	leaf = (xfs_attr_leafblock_t *)tmpbuffer;
817 	xfs_attr3_leaf_hdr_from_disk(&ichdr, leaf);
818 	entry = xfs_attr3_leaf_entryp(leaf);
819 
820 	/* XXX (dgc): buffer is about to be marked stale - why zero it? */
821 	memset(bp->b_addr, 0, args->geo->blksize);
822 
823 	/*
824 	 * Clean out the prior contents of the attribute list.
825 	 */
826 	error = xfs_da_shrink_inode(args, 0, bp);
827 	if (error)
828 		goto out;
829 
830 	if (forkoff == -1) {
831 		ASSERT(dp->i_mount->m_flags & XFS_MOUNT_ATTR2);
832 		ASSERT(dp->i_d.di_format != XFS_DINODE_FMT_BTREE);
833 		xfs_attr_fork_reset(dp, args->trans);
834 		goto out;
835 	}
836 
837 	xfs_attr_shortform_create(args);
838 
839 	/*
840 	 * Copy the attributes
841 	 */
842 	memset((char *)&nargs, 0, sizeof(nargs));
843 	nargs.geo = args->geo;
844 	nargs.dp = dp;
845 	nargs.firstblock = args->firstblock;
846 	nargs.flist = args->flist;
847 	nargs.total = args->total;
848 	nargs.whichfork = XFS_ATTR_FORK;
849 	nargs.trans = args->trans;
850 	nargs.op_flags = XFS_DA_OP_OKNOENT;
851 
852 	for (i = 0; i < ichdr.count; entry++, i++) {
853 		if (entry->flags & XFS_ATTR_INCOMPLETE)
854 			continue;	/* don't copy partial entries */
855 		if (!entry->nameidx)
856 			continue;
857 		ASSERT(entry->flags & XFS_ATTR_LOCAL);
858 		name_loc = xfs_attr3_leaf_name_local(leaf, i);
859 		nargs.name = name_loc->nameval;
860 		nargs.namelen = name_loc->namelen;
861 		nargs.value = &name_loc->nameval[nargs.namelen];
862 		nargs.valuelen = be16_to_cpu(name_loc->valuelen);
863 		nargs.hashval = be32_to_cpu(entry->hashval);
864 		nargs.flags = XFS_ATTR_NSP_ONDISK_TO_ARGS(entry->flags);
865 		xfs_attr_shortform_add(&nargs, forkoff);
866 	}
867 	error = 0;
868 
869 out:
870 	kmem_free(tmpbuffer);
871 	return error;
872 }
873 
874 /*
875  * Convert from using a single leaf to a root node and a leaf.
876  */
877 int
878 xfs_attr3_leaf_to_node(
879 	struct xfs_da_args	*args)
880 {
881 	struct xfs_attr_leafblock *leaf;
882 	struct xfs_attr3_icleaf_hdr icleafhdr;
883 	struct xfs_attr_leaf_entry *entries;
884 	struct xfs_da_node_entry *btree;
885 	struct xfs_da3_icnode_hdr icnodehdr;
886 	struct xfs_da_intnode	*node;
887 	struct xfs_inode	*dp = args->dp;
888 	struct xfs_mount	*mp = dp->i_mount;
889 	struct xfs_buf		*bp1 = NULL;
890 	struct xfs_buf		*bp2 = NULL;
891 	xfs_dablk_t		blkno;
892 	int			error;
893 
894 	trace_xfs_attr_leaf_to_node(args);
895 
896 	error = xfs_da_grow_inode(args, &blkno);
897 	if (error)
898 		goto out;
899 	error = xfs_attr3_leaf_read(args->trans, dp, 0, -1, &bp1);
900 	if (error)
901 		goto out;
902 
903 	error = xfs_da_get_buf(args->trans, dp, blkno, -1, &bp2, XFS_ATTR_FORK);
904 	if (error)
905 		goto out;
906 
907 	/* copy leaf to new buffer, update identifiers */
908 	xfs_trans_buf_set_type(args->trans, bp2, XFS_BLFT_ATTR_LEAF_BUF);
909 	bp2->b_ops = bp1->b_ops;
910 	memcpy(bp2->b_addr, bp1->b_addr, args->geo->blksize);
911 	if (xfs_sb_version_hascrc(&mp->m_sb)) {
912 		struct xfs_da3_blkinfo *hdr3 = bp2->b_addr;
913 		hdr3->blkno = cpu_to_be64(bp2->b_bn);
914 	}
915 	xfs_trans_log_buf(args->trans, bp2, 0, args->geo->blksize - 1);
916 
917 	/*
918 	 * Set up the new root node.
919 	 */
920 	error = xfs_da3_node_create(args, 0, 1, &bp1, XFS_ATTR_FORK);
921 	if (error)
922 		goto out;
923 	node = bp1->b_addr;
924 	dp->d_ops->node_hdr_from_disk(&icnodehdr, node);
925 	btree = dp->d_ops->node_tree_p(node);
926 
927 	leaf = bp2->b_addr;
928 	xfs_attr3_leaf_hdr_from_disk(&icleafhdr, leaf);
929 	entries = xfs_attr3_leaf_entryp(leaf);
930 
931 	/* both on-disk, don't endian-flip twice */
932 	btree[0].hashval = entries[icleafhdr.count - 1].hashval;
933 	btree[0].before = cpu_to_be32(blkno);
934 	icnodehdr.count = 1;
935 	dp->d_ops->node_hdr_to_disk(node, &icnodehdr);
936 	xfs_trans_log_buf(args->trans, bp1, 0, args->geo->blksize - 1);
937 	error = 0;
938 out:
939 	return error;
940 }
941 
942 /*========================================================================
943  * Routines used for growing the Btree.
944  *========================================================================*/
945 
946 /*
947  * Create the initial contents of a leaf attribute list
948  * or a leaf in a node attribute list.
949  */
950 STATIC int
951 xfs_attr3_leaf_create(
952 	struct xfs_da_args	*args,
953 	xfs_dablk_t		blkno,
954 	struct xfs_buf		**bpp)
955 {
956 	struct xfs_attr_leafblock *leaf;
957 	struct xfs_attr3_icleaf_hdr ichdr;
958 	struct xfs_inode	*dp = args->dp;
959 	struct xfs_mount	*mp = dp->i_mount;
960 	struct xfs_buf		*bp;
961 	int			error;
962 
963 	trace_xfs_attr_leaf_create(args);
964 
965 	error = xfs_da_get_buf(args->trans, args->dp, blkno, -1, &bp,
966 					    XFS_ATTR_FORK);
967 	if (error)
968 		return error;
969 	bp->b_ops = &xfs_attr3_leaf_buf_ops;
970 	xfs_trans_buf_set_type(args->trans, bp, XFS_BLFT_ATTR_LEAF_BUF);
971 	leaf = bp->b_addr;
972 	memset(leaf, 0, args->geo->blksize);
973 
974 	memset(&ichdr, 0, sizeof(ichdr));
975 	ichdr.firstused = args->geo->blksize;
976 
977 	if (xfs_sb_version_hascrc(&mp->m_sb)) {
978 		struct xfs_da3_blkinfo *hdr3 = bp->b_addr;
979 
980 		ichdr.magic = XFS_ATTR3_LEAF_MAGIC;
981 
982 		hdr3->blkno = cpu_to_be64(bp->b_bn);
983 		hdr3->owner = cpu_to_be64(dp->i_ino);
984 		uuid_copy(&hdr3->uuid, &mp->m_sb.sb_uuid);
985 
986 		ichdr.freemap[0].base = sizeof(struct xfs_attr3_leaf_hdr);
987 	} else {
988 		ichdr.magic = XFS_ATTR_LEAF_MAGIC;
989 		ichdr.freemap[0].base = sizeof(struct xfs_attr_leaf_hdr);
990 	}
991 	ichdr.freemap[0].size = ichdr.firstused - ichdr.freemap[0].base;
992 
993 	xfs_attr3_leaf_hdr_to_disk(leaf, &ichdr);
994 	xfs_trans_log_buf(args->trans, bp, 0, args->geo->blksize - 1);
995 
996 	*bpp = bp;
997 	return 0;
998 }
999 
1000 /*
1001  * Split the leaf node, rebalance, then add the new entry.
1002  */
1003 int
1004 xfs_attr3_leaf_split(
1005 	struct xfs_da_state	*state,
1006 	struct xfs_da_state_blk	*oldblk,
1007 	struct xfs_da_state_blk	*newblk)
1008 {
1009 	xfs_dablk_t blkno;
1010 	int error;
1011 
1012 	trace_xfs_attr_leaf_split(state->args);
1013 
1014 	/*
1015 	 * Allocate space for a new leaf node.
1016 	 */
1017 	ASSERT(oldblk->magic == XFS_ATTR_LEAF_MAGIC);
1018 	error = xfs_da_grow_inode(state->args, &blkno);
1019 	if (error)
1020 		return error;
1021 	error = xfs_attr3_leaf_create(state->args, blkno, &newblk->bp);
1022 	if (error)
1023 		return error;
1024 	newblk->blkno = blkno;
1025 	newblk->magic = XFS_ATTR_LEAF_MAGIC;
1026 
1027 	/*
1028 	 * Rebalance the entries across the two leaves.
1029 	 * NOTE: rebalance() currently depends on the 2nd block being empty.
1030 	 */
1031 	xfs_attr3_leaf_rebalance(state, oldblk, newblk);
1032 	error = xfs_da3_blk_link(state, oldblk, newblk);
1033 	if (error)
1034 		return error;
1035 
1036 	/*
1037 	 * Save info on "old" attribute for "atomic rename" ops, leaf_add()
1038 	 * modifies the index/blkno/rmtblk/rmtblkcnt fields to show the
1039 	 * "new" attrs info.  Will need the "old" info to remove it later.
1040 	 *
1041 	 * Insert the "new" entry in the correct block.
1042 	 */
1043 	if (state->inleaf) {
1044 		trace_xfs_attr_leaf_add_old(state->args);
1045 		error = xfs_attr3_leaf_add(oldblk->bp, state->args);
1046 	} else {
1047 		trace_xfs_attr_leaf_add_new(state->args);
1048 		error = xfs_attr3_leaf_add(newblk->bp, state->args);
1049 	}
1050 
1051 	/*
1052 	 * Update last hashval in each block since we added the name.
1053 	 */
1054 	oldblk->hashval = xfs_attr_leaf_lasthash(oldblk->bp, NULL);
1055 	newblk->hashval = xfs_attr_leaf_lasthash(newblk->bp, NULL);
1056 	return error;
1057 }
1058 
1059 /*
1060  * Add a name to the leaf attribute list structure.
1061  */
1062 int
1063 xfs_attr3_leaf_add(
1064 	struct xfs_buf		*bp,
1065 	struct xfs_da_args	*args)
1066 {
1067 	struct xfs_attr_leafblock *leaf;
1068 	struct xfs_attr3_icleaf_hdr ichdr;
1069 	int			tablesize;
1070 	int			entsize;
1071 	int			sum;
1072 	int			tmp;
1073 	int			i;
1074 
1075 	trace_xfs_attr_leaf_add(args);
1076 
1077 	leaf = bp->b_addr;
1078 	xfs_attr3_leaf_hdr_from_disk(&ichdr, leaf);
1079 	ASSERT(args->index >= 0 && args->index <= ichdr.count);
1080 	entsize = xfs_attr_leaf_newentsize(args, NULL);
1081 
1082 	/*
1083 	 * Search through freemap for first-fit on new name length.
1084 	 * (may need to figure in size of entry struct too)
1085 	 */
1086 	tablesize = (ichdr.count + 1) * sizeof(xfs_attr_leaf_entry_t)
1087 					+ xfs_attr3_leaf_hdr_size(leaf);
1088 	for (sum = 0, i = XFS_ATTR_LEAF_MAPSIZE - 1; i >= 0; i--) {
1089 		if (tablesize > ichdr.firstused) {
1090 			sum += ichdr.freemap[i].size;
1091 			continue;
1092 		}
1093 		if (!ichdr.freemap[i].size)
1094 			continue;	/* no space in this map */
1095 		tmp = entsize;
1096 		if (ichdr.freemap[i].base < ichdr.firstused)
1097 			tmp += sizeof(xfs_attr_leaf_entry_t);
1098 		if (ichdr.freemap[i].size >= tmp) {
1099 			tmp = xfs_attr3_leaf_add_work(bp, &ichdr, args, i);
1100 			goto out_log_hdr;
1101 		}
1102 		sum += ichdr.freemap[i].size;
1103 	}
1104 
1105 	/*
1106 	 * If there are no holes in the address space of the block,
1107 	 * and we don't have enough freespace, then compaction will do us
1108 	 * no good and we should just give up.
1109 	 */
1110 	if (!ichdr.holes && sum < entsize)
1111 		return -ENOSPC;
1112 
1113 	/*
1114 	 * Compact the entries to coalesce free space.
1115 	 * This may change the hdr->count via dropping INCOMPLETE entries.
1116 	 */
1117 	xfs_attr3_leaf_compact(args, &ichdr, bp);
1118 
1119 	/*
1120 	 * After compaction, the block is guaranteed to have only one
1121 	 * free region, in freemap[0].  If it is not big enough, give up.
1122 	 */
1123 	if (ichdr.freemap[0].size < (entsize + sizeof(xfs_attr_leaf_entry_t))) {
1124 		tmp = -ENOSPC;
1125 		goto out_log_hdr;
1126 	}
1127 
1128 	tmp = xfs_attr3_leaf_add_work(bp, &ichdr, args, 0);
1129 
1130 out_log_hdr:
1131 	xfs_attr3_leaf_hdr_to_disk(leaf, &ichdr);
1132 	xfs_trans_log_buf(args->trans, bp,
1133 		XFS_DA_LOGRANGE(leaf, &leaf->hdr,
1134 				xfs_attr3_leaf_hdr_size(leaf)));
1135 	return tmp;
1136 }
1137 
1138 /*
1139  * Add a name to a leaf attribute list structure.
1140  */
1141 STATIC int
1142 xfs_attr3_leaf_add_work(
1143 	struct xfs_buf		*bp,
1144 	struct xfs_attr3_icleaf_hdr *ichdr,
1145 	struct xfs_da_args	*args,
1146 	int			mapindex)
1147 {
1148 	struct xfs_attr_leafblock *leaf;
1149 	struct xfs_attr_leaf_entry *entry;
1150 	struct xfs_attr_leaf_name_local *name_loc;
1151 	struct xfs_attr_leaf_name_remote *name_rmt;
1152 	struct xfs_mount	*mp;
1153 	int			tmp;
1154 	int			i;
1155 
1156 	trace_xfs_attr_leaf_add_work(args);
1157 
1158 	leaf = bp->b_addr;
1159 	ASSERT(mapindex >= 0 && mapindex < XFS_ATTR_LEAF_MAPSIZE);
1160 	ASSERT(args->index >= 0 && args->index <= ichdr->count);
1161 
1162 	/*
1163 	 * Force open some space in the entry array and fill it in.
1164 	 */
1165 	entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
1166 	if (args->index < ichdr->count) {
1167 		tmp  = ichdr->count - args->index;
1168 		tmp *= sizeof(xfs_attr_leaf_entry_t);
1169 		memmove(entry + 1, entry, tmp);
1170 		xfs_trans_log_buf(args->trans, bp,
1171 		    XFS_DA_LOGRANGE(leaf, entry, tmp + sizeof(*entry)));
1172 	}
1173 	ichdr->count++;
1174 
1175 	/*
1176 	 * Allocate space for the new string (at the end of the run).
1177 	 */
1178 	mp = args->trans->t_mountp;
1179 	ASSERT(ichdr->freemap[mapindex].base < args->geo->blksize);
1180 	ASSERT((ichdr->freemap[mapindex].base & 0x3) == 0);
1181 	ASSERT(ichdr->freemap[mapindex].size >=
1182 		xfs_attr_leaf_newentsize(args, NULL));
1183 	ASSERT(ichdr->freemap[mapindex].size < args->geo->blksize);
1184 	ASSERT((ichdr->freemap[mapindex].size & 0x3) == 0);
1185 
1186 	ichdr->freemap[mapindex].size -= xfs_attr_leaf_newentsize(args, &tmp);
1187 
1188 	entry->nameidx = cpu_to_be16(ichdr->freemap[mapindex].base +
1189 				     ichdr->freemap[mapindex].size);
1190 	entry->hashval = cpu_to_be32(args->hashval);
1191 	entry->flags = tmp ? XFS_ATTR_LOCAL : 0;
1192 	entry->flags |= XFS_ATTR_NSP_ARGS_TO_ONDISK(args->flags);
1193 	if (args->op_flags & XFS_DA_OP_RENAME) {
1194 		entry->flags |= XFS_ATTR_INCOMPLETE;
1195 		if ((args->blkno2 == args->blkno) &&
1196 		    (args->index2 <= args->index)) {
1197 			args->index2++;
1198 		}
1199 	}
1200 	xfs_trans_log_buf(args->trans, bp,
1201 			  XFS_DA_LOGRANGE(leaf, entry, sizeof(*entry)));
1202 	ASSERT((args->index == 0) ||
1203 	       (be32_to_cpu(entry->hashval) >= be32_to_cpu((entry-1)->hashval)));
1204 	ASSERT((args->index == ichdr->count - 1) ||
1205 	       (be32_to_cpu(entry->hashval) <= be32_to_cpu((entry+1)->hashval)));
1206 
1207 	/*
1208 	 * For "remote" attribute values, simply note that we need to
1209 	 * allocate space for the "remote" value.  We can't actually
1210 	 * allocate the extents in this transaction, and we can't decide
1211 	 * which blocks they should be as we might allocate more blocks
1212 	 * as part of this transaction (a split operation for example).
1213 	 */
1214 	if (entry->flags & XFS_ATTR_LOCAL) {
1215 		name_loc = xfs_attr3_leaf_name_local(leaf, args->index);
1216 		name_loc->namelen = args->namelen;
1217 		name_loc->valuelen = cpu_to_be16(args->valuelen);
1218 		memcpy((char *)name_loc->nameval, args->name, args->namelen);
1219 		memcpy((char *)&name_loc->nameval[args->namelen], args->value,
1220 				   be16_to_cpu(name_loc->valuelen));
1221 	} else {
1222 		name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
1223 		name_rmt->namelen = args->namelen;
1224 		memcpy((char *)name_rmt->name, args->name, args->namelen);
1225 		entry->flags |= XFS_ATTR_INCOMPLETE;
1226 		/* just in case */
1227 		name_rmt->valuelen = 0;
1228 		name_rmt->valueblk = 0;
1229 		args->rmtblkno = 1;
1230 		args->rmtblkcnt = xfs_attr3_rmt_blocks(mp, args->valuelen);
1231 		args->rmtvaluelen = args->valuelen;
1232 	}
1233 	xfs_trans_log_buf(args->trans, bp,
1234 	     XFS_DA_LOGRANGE(leaf, xfs_attr3_leaf_name(leaf, args->index),
1235 				   xfs_attr_leaf_entsize(leaf, args->index)));
1236 
1237 	/*
1238 	 * Update the control info for this leaf node
1239 	 */
1240 	if (be16_to_cpu(entry->nameidx) < ichdr->firstused)
1241 		ichdr->firstused = be16_to_cpu(entry->nameidx);
1242 
1243 	ASSERT(ichdr->firstused >= ichdr->count * sizeof(xfs_attr_leaf_entry_t)
1244 					+ xfs_attr3_leaf_hdr_size(leaf));
1245 	tmp = (ichdr->count - 1) * sizeof(xfs_attr_leaf_entry_t)
1246 					+ xfs_attr3_leaf_hdr_size(leaf);
1247 
1248 	for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
1249 		if (ichdr->freemap[i].base == tmp) {
1250 			ichdr->freemap[i].base += sizeof(xfs_attr_leaf_entry_t);
1251 			ichdr->freemap[i].size -= sizeof(xfs_attr_leaf_entry_t);
1252 		}
1253 	}
1254 	ichdr->usedbytes += xfs_attr_leaf_entsize(leaf, args->index);
1255 	return 0;
1256 }
1257 
1258 /*
1259  * Garbage collect a leaf attribute list block by copying it to a new buffer.
1260  */
1261 STATIC void
1262 xfs_attr3_leaf_compact(
1263 	struct xfs_da_args	*args,
1264 	struct xfs_attr3_icleaf_hdr *ichdr_dst,
1265 	struct xfs_buf		*bp)
1266 {
1267 	struct xfs_attr_leafblock *leaf_src;
1268 	struct xfs_attr_leafblock *leaf_dst;
1269 	struct xfs_attr3_icleaf_hdr ichdr_src;
1270 	struct xfs_trans	*trans = args->trans;
1271 	char			*tmpbuffer;
1272 
1273 	trace_xfs_attr_leaf_compact(args);
1274 
1275 	tmpbuffer = kmem_alloc(args->geo->blksize, KM_SLEEP);
1276 	memcpy(tmpbuffer, bp->b_addr, args->geo->blksize);
1277 	memset(bp->b_addr, 0, args->geo->blksize);
1278 	leaf_src = (xfs_attr_leafblock_t *)tmpbuffer;
1279 	leaf_dst = bp->b_addr;
1280 
1281 	/*
1282 	 * Copy the on-disk header back into the destination buffer to ensure
1283 	 * all the information in the header that is not part of the incore
1284 	 * header structure is preserved.
1285 	 */
1286 	memcpy(bp->b_addr, tmpbuffer, xfs_attr3_leaf_hdr_size(leaf_src));
1287 
1288 	/* Initialise the incore headers */
1289 	ichdr_src = *ichdr_dst;	/* struct copy */
1290 	ichdr_dst->firstused = args->geo->blksize;
1291 	ichdr_dst->usedbytes = 0;
1292 	ichdr_dst->count = 0;
1293 	ichdr_dst->holes = 0;
1294 	ichdr_dst->freemap[0].base = xfs_attr3_leaf_hdr_size(leaf_src);
1295 	ichdr_dst->freemap[0].size = ichdr_dst->firstused -
1296 						ichdr_dst->freemap[0].base;
1297 
1298 	/* write the header back to initialise the underlying buffer */
1299 	xfs_attr3_leaf_hdr_to_disk(leaf_dst, ichdr_dst);
1300 
1301 	/*
1302 	 * Copy all entry's in the same (sorted) order,
1303 	 * but allocate name/value pairs packed and in sequence.
1304 	 */
1305 	xfs_attr3_leaf_moveents(args, leaf_src, &ichdr_src, 0,
1306 				leaf_dst, ichdr_dst, 0, ichdr_src.count);
1307 	/*
1308 	 * this logs the entire buffer, but the caller must write the header
1309 	 * back to the buffer when it is finished modifying it.
1310 	 */
1311 	xfs_trans_log_buf(trans, bp, 0, args->geo->blksize - 1);
1312 
1313 	kmem_free(tmpbuffer);
1314 }
1315 
1316 /*
1317  * Compare two leaf blocks "order".
1318  * Return 0 unless leaf2 should go before leaf1.
1319  */
1320 static int
1321 xfs_attr3_leaf_order(
1322 	struct xfs_buf	*leaf1_bp,
1323 	struct xfs_attr3_icleaf_hdr *leaf1hdr,
1324 	struct xfs_buf	*leaf2_bp,
1325 	struct xfs_attr3_icleaf_hdr *leaf2hdr)
1326 {
1327 	struct xfs_attr_leaf_entry *entries1;
1328 	struct xfs_attr_leaf_entry *entries2;
1329 
1330 	entries1 = xfs_attr3_leaf_entryp(leaf1_bp->b_addr);
1331 	entries2 = xfs_attr3_leaf_entryp(leaf2_bp->b_addr);
1332 	if (leaf1hdr->count > 0 && leaf2hdr->count > 0 &&
1333 	    ((be32_to_cpu(entries2[0].hashval) <
1334 	      be32_to_cpu(entries1[0].hashval)) ||
1335 	     (be32_to_cpu(entries2[leaf2hdr->count - 1].hashval) <
1336 	      be32_to_cpu(entries1[leaf1hdr->count - 1].hashval)))) {
1337 		return 1;
1338 	}
1339 	return 0;
1340 }
1341 
1342 int
1343 xfs_attr_leaf_order(
1344 	struct xfs_buf	*leaf1_bp,
1345 	struct xfs_buf	*leaf2_bp)
1346 {
1347 	struct xfs_attr3_icleaf_hdr ichdr1;
1348 	struct xfs_attr3_icleaf_hdr ichdr2;
1349 
1350 	xfs_attr3_leaf_hdr_from_disk(&ichdr1, leaf1_bp->b_addr);
1351 	xfs_attr3_leaf_hdr_from_disk(&ichdr2, leaf2_bp->b_addr);
1352 	return xfs_attr3_leaf_order(leaf1_bp, &ichdr1, leaf2_bp, &ichdr2);
1353 }
1354 
1355 /*
1356  * Redistribute the attribute list entries between two leaf nodes,
1357  * taking into account the size of the new entry.
1358  *
1359  * NOTE: if new block is empty, then it will get the upper half of the
1360  * old block.  At present, all (one) callers pass in an empty second block.
1361  *
1362  * This code adjusts the args->index/blkno and args->index2/blkno2 fields
1363  * to match what it is doing in splitting the attribute leaf block.  Those
1364  * values are used in "atomic rename" operations on attributes.  Note that
1365  * the "new" and "old" values can end up in different blocks.
1366  */
1367 STATIC void
1368 xfs_attr3_leaf_rebalance(
1369 	struct xfs_da_state	*state,
1370 	struct xfs_da_state_blk	*blk1,
1371 	struct xfs_da_state_blk	*blk2)
1372 {
1373 	struct xfs_da_args	*args;
1374 	struct xfs_attr_leafblock *leaf1;
1375 	struct xfs_attr_leafblock *leaf2;
1376 	struct xfs_attr3_icleaf_hdr ichdr1;
1377 	struct xfs_attr3_icleaf_hdr ichdr2;
1378 	struct xfs_attr_leaf_entry *entries1;
1379 	struct xfs_attr_leaf_entry *entries2;
1380 	int			count;
1381 	int			totallen;
1382 	int			max;
1383 	int			space;
1384 	int			swap;
1385 
1386 	/*
1387 	 * Set up environment.
1388 	 */
1389 	ASSERT(blk1->magic == XFS_ATTR_LEAF_MAGIC);
1390 	ASSERT(blk2->magic == XFS_ATTR_LEAF_MAGIC);
1391 	leaf1 = blk1->bp->b_addr;
1392 	leaf2 = blk2->bp->b_addr;
1393 	xfs_attr3_leaf_hdr_from_disk(&ichdr1, leaf1);
1394 	xfs_attr3_leaf_hdr_from_disk(&ichdr2, leaf2);
1395 	ASSERT(ichdr2.count == 0);
1396 	args = state->args;
1397 
1398 	trace_xfs_attr_leaf_rebalance(args);
1399 
1400 	/*
1401 	 * Check ordering of blocks, reverse if it makes things simpler.
1402 	 *
1403 	 * NOTE: Given that all (current) callers pass in an empty
1404 	 * second block, this code should never set "swap".
1405 	 */
1406 	swap = 0;
1407 	if (xfs_attr3_leaf_order(blk1->bp, &ichdr1, blk2->bp, &ichdr2)) {
1408 		struct xfs_da_state_blk	*tmp_blk;
1409 		struct xfs_attr3_icleaf_hdr tmp_ichdr;
1410 
1411 		tmp_blk = blk1;
1412 		blk1 = blk2;
1413 		blk2 = tmp_blk;
1414 
1415 		/* struct copies to swap them rather than reconverting */
1416 		tmp_ichdr = ichdr1;
1417 		ichdr1 = ichdr2;
1418 		ichdr2 = tmp_ichdr;
1419 
1420 		leaf1 = blk1->bp->b_addr;
1421 		leaf2 = blk2->bp->b_addr;
1422 		swap = 1;
1423 	}
1424 
1425 	/*
1426 	 * Examine entries until we reduce the absolute difference in
1427 	 * byte usage between the two blocks to a minimum.  Then get
1428 	 * the direction to copy and the number of elements to move.
1429 	 *
1430 	 * "inleaf" is true if the new entry should be inserted into blk1.
1431 	 * If "swap" is also true, then reverse the sense of "inleaf".
1432 	 */
1433 	state->inleaf = xfs_attr3_leaf_figure_balance(state, blk1, &ichdr1,
1434 						      blk2, &ichdr2,
1435 						      &count, &totallen);
1436 	if (swap)
1437 		state->inleaf = !state->inleaf;
1438 
1439 	/*
1440 	 * Move any entries required from leaf to leaf:
1441 	 */
1442 	if (count < ichdr1.count) {
1443 		/*
1444 		 * Figure the total bytes to be added to the destination leaf.
1445 		 */
1446 		/* number entries being moved */
1447 		count = ichdr1.count - count;
1448 		space  = ichdr1.usedbytes - totallen;
1449 		space += count * sizeof(xfs_attr_leaf_entry_t);
1450 
1451 		/*
1452 		 * leaf2 is the destination, compact it if it looks tight.
1453 		 */
1454 		max  = ichdr2.firstused - xfs_attr3_leaf_hdr_size(leaf1);
1455 		max -= ichdr2.count * sizeof(xfs_attr_leaf_entry_t);
1456 		if (space > max)
1457 			xfs_attr3_leaf_compact(args, &ichdr2, blk2->bp);
1458 
1459 		/*
1460 		 * Move high entries from leaf1 to low end of leaf2.
1461 		 */
1462 		xfs_attr3_leaf_moveents(args, leaf1, &ichdr1,
1463 				ichdr1.count - count, leaf2, &ichdr2, 0, count);
1464 
1465 	} else if (count > ichdr1.count) {
1466 		/*
1467 		 * I assert that since all callers pass in an empty
1468 		 * second buffer, this code should never execute.
1469 		 */
1470 		ASSERT(0);
1471 
1472 		/*
1473 		 * Figure the total bytes to be added to the destination leaf.
1474 		 */
1475 		/* number entries being moved */
1476 		count -= ichdr1.count;
1477 		space  = totallen - ichdr1.usedbytes;
1478 		space += count * sizeof(xfs_attr_leaf_entry_t);
1479 
1480 		/*
1481 		 * leaf1 is the destination, compact it if it looks tight.
1482 		 */
1483 		max  = ichdr1.firstused - xfs_attr3_leaf_hdr_size(leaf1);
1484 		max -= ichdr1.count * sizeof(xfs_attr_leaf_entry_t);
1485 		if (space > max)
1486 			xfs_attr3_leaf_compact(args, &ichdr1, blk1->bp);
1487 
1488 		/*
1489 		 * Move low entries from leaf2 to high end of leaf1.
1490 		 */
1491 		xfs_attr3_leaf_moveents(args, leaf2, &ichdr2, 0, leaf1, &ichdr1,
1492 					ichdr1.count, count);
1493 	}
1494 
1495 	xfs_attr3_leaf_hdr_to_disk(leaf1, &ichdr1);
1496 	xfs_attr3_leaf_hdr_to_disk(leaf2, &ichdr2);
1497 	xfs_trans_log_buf(args->trans, blk1->bp, 0, args->geo->blksize - 1);
1498 	xfs_trans_log_buf(args->trans, blk2->bp, 0, args->geo->blksize - 1);
1499 
1500 	/*
1501 	 * Copy out last hashval in each block for B-tree code.
1502 	 */
1503 	entries1 = xfs_attr3_leaf_entryp(leaf1);
1504 	entries2 = xfs_attr3_leaf_entryp(leaf2);
1505 	blk1->hashval = be32_to_cpu(entries1[ichdr1.count - 1].hashval);
1506 	blk2->hashval = be32_to_cpu(entries2[ichdr2.count - 1].hashval);
1507 
1508 	/*
1509 	 * Adjust the expected index for insertion.
1510 	 * NOTE: this code depends on the (current) situation that the
1511 	 * second block was originally empty.
1512 	 *
1513 	 * If the insertion point moved to the 2nd block, we must adjust
1514 	 * the index.  We must also track the entry just following the
1515 	 * new entry for use in an "atomic rename" operation, that entry
1516 	 * is always the "old" entry and the "new" entry is what we are
1517 	 * inserting.  The index/blkno fields refer to the "old" entry,
1518 	 * while the index2/blkno2 fields refer to the "new" entry.
1519 	 */
1520 	if (blk1->index > ichdr1.count) {
1521 		ASSERT(state->inleaf == 0);
1522 		blk2->index = blk1->index - ichdr1.count;
1523 		args->index = args->index2 = blk2->index;
1524 		args->blkno = args->blkno2 = blk2->blkno;
1525 	} else if (blk1->index == ichdr1.count) {
1526 		if (state->inleaf) {
1527 			args->index = blk1->index;
1528 			args->blkno = blk1->blkno;
1529 			args->index2 = 0;
1530 			args->blkno2 = blk2->blkno;
1531 		} else {
1532 			/*
1533 			 * On a double leaf split, the original attr location
1534 			 * is already stored in blkno2/index2, so don't
1535 			 * overwrite it overwise we corrupt the tree.
1536 			 */
1537 			blk2->index = blk1->index - ichdr1.count;
1538 			args->index = blk2->index;
1539 			args->blkno = blk2->blkno;
1540 			if (!state->extravalid) {
1541 				/*
1542 				 * set the new attr location to match the old
1543 				 * one and let the higher level split code
1544 				 * decide where in the leaf to place it.
1545 				 */
1546 				args->index2 = blk2->index;
1547 				args->blkno2 = blk2->blkno;
1548 			}
1549 		}
1550 	} else {
1551 		ASSERT(state->inleaf == 1);
1552 		args->index = args->index2 = blk1->index;
1553 		args->blkno = args->blkno2 = blk1->blkno;
1554 	}
1555 }
1556 
1557 /*
1558  * Examine entries until we reduce the absolute difference in
1559  * byte usage between the two blocks to a minimum.
1560  * GROT: Is this really necessary?  With other than a 512 byte blocksize,
1561  * GROT: there will always be enough room in either block for a new entry.
1562  * GROT: Do a double-split for this case?
1563  */
1564 STATIC int
1565 xfs_attr3_leaf_figure_balance(
1566 	struct xfs_da_state		*state,
1567 	struct xfs_da_state_blk		*blk1,
1568 	struct xfs_attr3_icleaf_hdr	*ichdr1,
1569 	struct xfs_da_state_blk		*blk2,
1570 	struct xfs_attr3_icleaf_hdr	*ichdr2,
1571 	int				*countarg,
1572 	int				*usedbytesarg)
1573 {
1574 	struct xfs_attr_leafblock	*leaf1 = blk1->bp->b_addr;
1575 	struct xfs_attr_leafblock	*leaf2 = blk2->bp->b_addr;
1576 	struct xfs_attr_leaf_entry	*entry;
1577 	int				count;
1578 	int				max;
1579 	int				index;
1580 	int				totallen = 0;
1581 	int				half;
1582 	int				lastdelta;
1583 	int				foundit = 0;
1584 	int				tmp;
1585 
1586 	/*
1587 	 * Examine entries until we reduce the absolute difference in
1588 	 * byte usage between the two blocks to a minimum.
1589 	 */
1590 	max = ichdr1->count + ichdr2->count;
1591 	half = (max + 1) * sizeof(*entry);
1592 	half += ichdr1->usedbytes + ichdr2->usedbytes +
1593 			xfs_attr_leaf_newentsize(state->args, NULL);
1594 	half /= 2;
1595 	lastdelta = state->args->geo->blksize;
1596 	entry = xfs_attr3_leaf_entryp(leaf1);
1597 	for (count = index = 0; count < max; entry++, index++, count++) {
1598 
1599 #define XFS_ATTR_ABS(A)	(((A) < 0) ? -(A) : (A))
1600 		/*
1601 		 * The new entry is in the first block, account for it.
1602 		 */
1603 		if (count == blk1->index) {
1604 			tmp = totallen + sizeof(*entry) +
1605 				xfs_attr_leaf_newentsize(state->args, NULL);
1606 			if (XFS_ATTR_ABS(half - tmp) > lastdelta)
1607 				break;
1608 			lastdelta = XFS_ATTR_ABS(half - tmp);
1609 			totallen = tmp;
1610 			foundit = 1;
1611 		}
1612 
1613 		/*
1614 		 * Wrap around into the second block if necessary.
1615 		 */
1616 		if (count == ichdr1->count) {
1617 			leaf1 = leaf2;
1618 			entry = xfs_attr3_leaf_entryp(leaf1);
1619 			index = 0;
1620 		}
1621 
1622 		/*
1623 		 * Figure out if next leaf entry would be too much.
1624 		 */
1625 		tmp = totallen + sizeof(*entry) + xfs_attr_leaf_entsize(leaf1,
1626 									index);
1627 		if (XFS_ATTR_ABS(half - tmp) > lastdelta)
1628 			break;
1629 		lastdelta = XFS_ATTR_ABS(half - tmp);
1630 		totallen = tmp;
1631 #undef XFS_ATTR_ABS
1632 	}
1633 
1634 	/*
1635 	 * Calculate the number of usedbytes that will end up in lower block.
1636 	 * If new entry not in lower block, fix up the count.
1637 	 */
1638 	totallen -= count * sizeof(*entry);
1639 	if (foundit) {
1640 		totallen -= sizeof(*entry) +
1641 				xfs_attr_leaf_newentsize(state->args, NULL);
1642 	}
1643 
1644 	*countarg = count;
1645 	*usedbytesarg = totallen;
1646 	return foundit;
1647 }
1648 
1649 /*========================================================================
1650  * Routines used for shrinking the Btree.
1651  *========================================================================*/
1652 
1653 /*
1654  * Check a leaf block and its neighbors to see if the block should be
1655  * collapsed into one or the other neighbor.  Always keep the block
1656  * with the smaller block number.
1657  * If the current block is over 50% full, don't try to join it, return 0.
1658  * If the block is empty, fill in the state structure and return 2.
1659  * If it can be collapsed, fill in the state structure and return 1.
1660  * If nothing can be done, return 0.
1661  *
1662  * GROT: allow for INCOMPLETE entries in calculation.
1663  */
1664 int
1665 xfs_attr3_leaf_toosmall(
1666 	struct xfs_da_state	*state,
1667 	int			*action)
1668 {
1669 	struct xfs_attr_leafblock *leaf;
1670 	struct xfs_da_state_blk	*blk;
1671 	struct xfs_attr3_icleaf_hdr ichdr;
1672 	struct xfs_buf		*bp;
1673 	xfs_dablk_t		blkno;
1674 	int			bytes;
1675 	int			forward;
1676 	int			error;
1677 	int			retval;
1678 	int			i;
1679 
1680 	trace_xfs_attr_leaf_toosmall(state->args);
1681 
1682 	/*
1683 	 * Check for the degenerate case of the block being over 50% full.
1684 	 * If so, it's not worth even looking to see if we might be able
1685 	 * to coalesce with a sibling.
1686 	 */
1687 	blk = &state->path.blk[ state->path.active-1 ];
1688 	leaf = blk->bp->b_addr;
1689 	xfs_attr3_leaf_hdr_from_disk(&ichdr, leaf);
1690 	bytes = xfs_attr3_leaf_hdr_size(leaf) +
1691 		ichdr.count * sizeof(xfs_attr_leaf_entry_t) +
1692 		ichdr.usedbytes;
1693 	if (bytes > (state->args->geo->blksize >> 1)) {
1694 		*action = 0;	/* blk over 50%, don't try to join */
1695 		return 0;
1696 	}
1697 
1698 	/*
1699 	 * Check for the degenerate case of the block being empty.
1700 	 * If the block is empty, we'll simply delete it, no need to
1701 	 * coalesce it with a sibling block.  We choose (arbitrarily)
1702 	 * to merge with the forward block unless it is NULL.
1703 	 */
1704 	if (ichdr.count == 0) {
1705 		/*
1706 		 * Make altpath point to the block we want to keep and
1707 		 * path point to the block we want to drop (this one).
1708 		 */
1709 		forward = (ichdr.forw != 0);
1710 		memcpy(&state->altpath, &state->path, sizeof(state->path));
1711 		error = xfs_da3_path_shift(state, &state->altpath, forward,
1712 						 0, &retval);
1713 		if (error)
1714 			return error;
1715 		if (retval) {
1716 			*action = 0;
1717 		} else {
1718 			*action = 2;
1719 		}
1720 		return 0;
1721 	}
1722 
1723 	/*
1724 	 * Examine each sibling block to see if we can coalesce with
1725 	 * at least 25% free space to spare.  We need to figure out
1726 	 * whether to merge with the forward or the backward block.
1727 	 * We prefer coalescing with the lower numbered sibling so as
1728 	 * to shrink an attribute list over time.
1729 	 */
1730 	/* start with smaller blk num */
1731 	forward = ichdr.forw < ichdr.back;
1732 	for (i = 0; i < 2; forward = !forward, i++) {
1733 		struct xfs_attr3_icleaf_hdr ichdr2;
1734 		if (forward)
1735 			blkno = ichdr.forw;
1736 		else
1737 			blkno = ichdr.back;
1738 		if (blkno == 0)
1739 			continue;
1740 		error = xfs_attr3_leaf_read(state->args->trans, state->args->dp,
1741 					blkno, -1, &bp);
1742 		if (error)
1743 			return error;
1744 
1745 		xfs_attr3_leaf_hdr_from_disk(&ichdr2, bp->b_addr);
1746 
1747 		bytes = state->args->geo->blksize -
1748 			(state->args->geo->blksize >> 2) -
1749 			ichdr.usedbytes - ichdr2.usedbytes -
1750 			((ichdr.count + ichdr2.count) *
1751 					sizeof(xfs_attr_leaf_entry_t)) -
1752 			xfs_attr3_leaf_hdr_size(leaf);
1753 
1754 		xfs_trans_brelse(state->args->trans, bp);
1755 		if (bytes >= 0)
1756 			break;	/* fits with at least 25% to spare */
1757 	}
1758 	if (i >= 2) {
1759 		*action = 0;
1760 		return 0;
1761 	}
1762 
1763 	/*
1764 	 * Make altpath point to the block we want to keep (the lower
1765 	 * numbered block) and path point to the block we want to drop.
1766 	 */
1767 	memcpy(&state->altpath, &state->path, sizeof(state->path));
1768 	if (blkno < blk->blkno) {
1769 		error = xfs_da3_path_shift(state, &state->altpath, forward,
1770 						 0, &retval);
1771 	} else {
1772 		error = xfs_da3_path_shift(state, &state->path, forward,
1773 						 0, &retval);
1774 	}
1775 	if (error)
1776 		return error;
1777 	if (retval) {
1778 		*action = 0;
1779 	} else {
1780 		*action = 1;
1781 	}
1782 	return 0;
1783 }
1784 
1785 /*
1786  * Remove a name from the leaf attribute list structure.
1787  *
1788  * Return 1 if leaf is less than 37% full, 0 if >= 37% full.
1789  * If two leaves are 37% full, when combined they will leave 25% free.
1790  */
1791 int
1792 xfs_attr3_leaf_remove(
1793 	struct xfs_buf		*bp,
1794 	struct xfs_da_args	*args)
1795 {
1796 	struct xfs_attr_leafblock *leaf;
1797 	struct xfs_attr3_icleaf_hdr ichdr;
1798 	struct xfs_attr_leaf_entry *entry;
1799 	int			before;
1800 	int			after;
1801 	int			smallest;
1802 	int			entsize;
1803 	int			tablesize;
1804 	int			tmp;
1805 	int			i;
1806 
1807 	trace_xfs_attr_leaf_remove(args);
1808 
1809 	leaf = bp->b_addr;
1810 	xfs_attr3_leaf_hdr_from_disk(&ichdr, leaf);
1811 
1812 	ASSERT(ichdr.count > 0 && ichdr.count < args->geo->blksize / 8);
1813 	ASSERT(args->index >= 0 && args->index < ichdr.count);
1814 	ASSERT(ichdr.firstused >= ichdr.count * sizeof(*entry) +
1815 					xfs_attr3_leaf_hdr_size(leaf));
1816 
1817 	entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
1818 
1819 	ASSERT(be16_to_cpu(entry->nameidx) >= ichdr.firstused);
1820 	ASSERT(be16_to_cpu(entry->nameidx) < args->geo->blksize);
1821 
1822 	/*
1823 	 * Scan through free region table:
1824 	 *    check for adjacency of free'd entry with an existing one,
1825 	 *    find smallest free region in case we need to replace it,
1826 	 *    adjust any map that borders the entry table,
1827 	 */
1828 	tablesize = ichdr.count * sizeof(xfs_attr_leaf_entry_t)
1829 					+ xfs_attr3_leaf_hdr_size(leaf);
1830 	tmp = ichdr.freemap[0].size;
1831 	before = after = -1;
1832 	smallest = XFS_ATTR_LEAF_MAPSIZE - 1;
1833 	entsize = xfs_attr_leaf_entsize(leaf, args->index);
1834 	for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
1835 		ASSERT(ichdr.freemap[i].base < args->geo->blksize);
1836 		ASSERT(ichdr.freemap[i].size < args->geo->blksize);
1837 		if (ichdr.freemap[i].base == tablesize) {
1838 			ichdr.freemap[i].base -= sizeof(xfs_attr_leaf_entry_t);
1839 			ichdr.freemap[i].size += sizeof(xfs_attr_leaf_entry_t);
1840 		}
1841 
1842 		if (ichdr.freemap[i].base + ichdr.freemap[i].size ==
1843 				be16_to_cpu(entry->nameidx)) {
1844 			before = i;
1845 		} else if (ichdr.freemap[i].base ==
1846 				(be16_to_cpu(entry->nameidx) + entsize)) {
1847 			after = i;
1848 		} else if (ichdr.freemap[i].size < tmp) {
1849 			tmp = ichdr.freemap[i].size;
1850 			smallest = i;
1851 		}
1852 	}
1853 
1854 	/*
1855 	 * Coalesce adjacent freemap regions,
1856 	 * or replace the smallest region.
1857 	 */
1858 	if ((before >= 0) || (after >= 0)) {
1859 		if ((before >= 0) && (after >= 0)) {
1860 			ichdr.freemap[before].size += entsize;
1861 			ichdr.freemap[before].size += ichdr.freemap[after].size;
1862 			ichdr.freemap[after].base = 0;
1863 			ichdr.freemap[after].size = 0;
1864 		} else if (before >= 0) {
1865 			ichdr.freemap[before].size += entsize;
1866 		} else {
1867 			ichdr.freemap[after].base = be16_to_cpu(entry->nameidx);
1868 			ichdr.freemap[after].size += entsize;
1869 		}
1870 	} else {
1871 		/*
1872 		 * Replace smallest region (if it is smaller than free'd entry)
1873 		 */
1874 		if (ichdr.freemap[smallest].size < entsize) {
1875 			ichdr.freemap[smallest].base = be16_to_cpu(entry->nameidx);
1876 			ichdr.freemap[smallest].size = entsize;
1877 		}
1878 	}
1879 
1880 	/*
1881 	 * Did we remove the first entry?
1882 	 */
1883 	if (be16_to_cpu(entry->nameidx) == ichdr.firstused)
1884 		smallest = 1;
1885 	else
1886 		smallest = 0;
1887 
1888 	/*
1889 	 * Compress the remaining entries and zero out the removed stuff.
1890 	 */
1891 	memset(xfs_attr3_leaf_name(leaf, args->index), 0, entsize);
1892 	ichdr.usedbytes -= entsize;
1893 	xfs_trans_log_buf(args->trans, bp,
1894 	     XFS_DA_LOGRANGE(leaf, xfs_attr3_leaf_name(leaf, args->index),
1895 				   entsize));
1896 
1897 	tmp = (ichdr.count - args->index) * sizeof(xfs_attr_leaf_entry_t);
1898 	memmove(entry, entry + 1, tmp);
1899 	ichdr.count--;
1900 	xfs_trans_log_buf(args->trans, bp,
1901 	    XFS_DA_LOGRANGE(leaf, entry, tmp + sizeof(xfs_attr_leaf_entry_t)));
1902 
1903 	entry = &xfs_attr3_leaf_entryp(leaf)[ichdr.count];
1904 	memset(entry, 0, sizeof(xfs_attr_leaf_entry_t));
1905 
1906 	/*
1907 	 * If we removed the first entry, re-find the first used byte
1908 	 * in the name area.  Note that if the entry was the "firstused",
1909 	 * then we don't have a "hole" in our block resulting from
1910 	 * removing the name.
1911 	 */
1912 	if (smallest) {
1913 		tmp = args->geo->blksize;
1914 		entry = xfs_attr3_leaf_entryp(leaf);
1915 		for (i = ichdr.count - 1; i >= 0; entry++, i--) {
1916 			ASSERT(be16_to_cpu(entry->nameidx) >= ichdr.firstused);
1917 			ASSERT(be16_to_cpu(entry->nameidx) < args->geo->blksize);
1918 
1919 			if (be16_to_cpu(entry->nameidx) < tmp)
1920 				tmp = be16_to_cpu(entry->nameidx);
1921 		}
1922 		ichdr.firstused = tmp;
1923 		if (!ichdr.firstused)
1924 			ichdr.firstused = tmp - XFS_ATTR_LEAF_NAME_ALIGN;
1925 	} else {
1926 		ichdr.holes = 1;	/* mark as needing compaction */
1927 	}
1928 	xfs_attr3_leaf_hdr_to_disk(leaf, &ichdr);
1929 	xfs_trans_log_buf(args->trans, bp,
1930 			  XFS_DA_LOGRANGE(leaf, &leaf->hdr,
1931 					  xfs_attr3_leaf_hdr_size(leaf)));
1932 
1933 	/*
1934 	 * Check if leaf is less than 50% full, caller may want to
1935 	 * "join" the leaf with a sibling if so.
1936 	 */
1937 	tmp = ichdr.usedbytes + xfs_attr3_leaf_hdr_size(leaf) +
1938 	      ichdr.count * sizeof(xfs_attr_leaf_entry_t);
1939 
1940 	return tmp < args->geo->magicpct; /* leaf is < 37% full */
1941 }
1942 
1943 /*
1944  * Move all the attribute list entries from drop_leaf into save_leaf.
1945  */
1946 void
1947 xfs_attr3_leaf_unbalance(
1948 	struct xfs_da_state	*state,
1949 	struct xfs_da_state_blk	*drop_blk,
1950 	struct xfs_da_state_blk	*save_blk)
1951 {
1952 	struct xfs_attr_leafblock *drop_leaf = drop_blk->bp->b_addr;
1953 	struct xfs_attr_leafblock *save_leaf = save_blk->bp->b_addr;
1954 	struct xfs_attr3_icleaf_hdr drophdr;
1955 	struct xfs_attr3_icleaf_hdr savehdr;
1956 	struct xfs_attr_leaf_entry *entry;
1957 
1958 	trace_xfs_attr_leaf_unbalance(state->args);
1959 
1960 	drop_leaf = drop_blk->bp->b_addr;
1961 	save_leaf = save_blk->bp->b_addr;
1962 	xfs_attr3_leaf_hdr_from_disk(&drophdr, drop_leaf);
1963 	xfs_attr3_leaf_hdr_from_disk(&savehdr, save_leaf);
1964 	entry = xfs_attr3_leaf_entryp(drop_leaf);
1965 
1966 	/*
1967 	 * Save last hashval from dying block for later Btree fixup.
1968 	 */
1969 	drop_blk->hashval = be32_to_cpu(entry[drophdr.count - 1].hashval);
1970 
1971 	/*
1972 	 * Check if we need a temp buffer, or can we do it in place.
1973 	 * Note that we don't check "leaf" for holes because we will
1974 	 * always be dropping it, toosmall() decided that for us already.
1975 	 */
1976 	if (savehdr.holes == 0) {
1977 		/*
1978 		 * dest leaf has no holes, so we add there.  May need
1979 		 * to make some room in the entry array.
1980 		 */
1981 		if (xfs_attr3_leaf_order(save_blk->bp, &savehdr,
1982 					 drop_blk->bp, &drophdr)) {
1983 			xfs_attr3_leaf_moveents(state->args,
1984 						drop_leaf, &drophdr, 0,
1985 						save_leaf, &savehdr, 0,
1986 						drophdr.count);
1987 		} else {
1988 			xfs_attr3_leaf_moveents(state->args,
1989 						drop_leaf, &drophdr, 0,
1990 						save_leaf, &savehdr,
1991 						savehdr.count, drophdr.count);
1992 		}
1993 	} else {
1994 		/*
1995 		 * Destination has holes, so we make a temporary copy
1996 		 * of the leaf and add them both to that.
1997 		 */
1998 		struct xfs_attr_leafblock *tmp_leaf;
1999 		struct xfs_attr3_icleaf_hdr tmphdr;
2000 
2001 		tmp_leaf = kmem_zalloc(state->args->geo->blksize, KM_SLEEP);
2002 
2003 		/*
2004 		 * Copy the header into the temp leaf so that all the stuff
2005 		 * not in the incore header is present and gets copied back in
2006 		 * once we've moved all the entries.
2007 		 */
2008 		memcpy(tmp_leaf, save_leaf, xfs_attr3_leaf_hdr_size(save_leaf));
2009 
2010 		memset(&tmphdr, 0, sizeof(tmphdr));
2011 		tmphdr.magic = savehdr.magic;
2012 		tmphdr.forw = savehdr.forw;
2013 		tmphdr.back = savehdr.back;
2014 		tmphdr.firstused = state->args->geo->blksize;
2015 
2016 		/* write the header to the temp buffer to initialise it */
2017 		xfs_attr3_leaf_hdr_to_disk(tmp_leaf, &tmphdr);
2018 
2019 		if (xfs_attr3_leaf_order(save_blk->bp, &savehdr,
2020 					 drop_blk->bp, &drophdr)) {
2021 			xfs_attr3_leaf_moveents(state->args,
2022 						drop_leaf, &drophdr, 0,
2023 						tmp_leaf, &tmphdr, 0,
2024 						drophdr.count);
2025 			xfs_attr3_leaf_moveents(state->args,
2026 						save_leaf, &savehdr, 0,
2027 						tmp_leaf, &tmphdr, tmphdr.count,
2028 						savehdr.count);
2029 		} else {
2030 			xfs_attr3_leaf_moveents(state->args,
2031 						save_leaf, &savehdr, 0,
2032 						tmp_leaf, &tmphdr, 0,
2033 						savehdr.count);
2034 			xfs_attr3_leaf_moveents(state->args,
2035 						drop_leaf, &drophdr, 0,
2036 						tmp_leaf, &tmphdr, tmphdr.count,
2037 						drophdr.count);
2038 		}
2039 		memcpy(save_leaf, tmp_leaf, state->args->geo->blksize);
2040 		savehdr = tmphdr; /* struct copy */
2041 		kmem_free(tmp_leaf);
2042 	}
2043 
2044 	xfs_attr3_leaf_hdr_to_disk(save_leaf, &savehdr);
2045 	xfs_trans_log_buf(state->args->trans, save_blk->bp, 0,
2046 					   state->args->geo->blksize - 1);
2047 
2048 	/*
2049 	 * Copy out last hashval in each block for B-tree code.
2050 	 */
2051 	entry = xfs_attr3_leaf_entryp(save_leaf);
2052 	save_blk->hashval = be32_to_cpu(entry[savehdr.count - 1].hashval);
2053 }
2054 
2055 /*========================================================================
2056  * Routines used for finding things in the Btree.
2057  *========================================================================*/
2058 
2059 /*
2060  * Look up a name in a leaf attribute list structure.
2061  * This is the internal routine, it uses the caller's buffer.
2062  *
2063  * Note that duplicate keys are allowed, but only check within the
2064  * current leaf node.  The Btree code must check in adjacent leaf nodes.
2065  *
2066  * Return in args->index the index into the entry[] array of either
2067  * the found entry, or where the entry should have been (insert before
2068  * that entry).
2069  *
2070  * Don't change the args->value unless we find the attribute.
2071  */
2072 int
2073 xfs_attr3_leaf_lookup_int(
2074 	struct xfs_buf		*bp,
2075 	struct xfs_da_args	*args)
2076 {
2077 	struct xfs_attr_leafblock *leaf;
2078 	struct xfs_attr3_icleaf_hdr ichdr;
2079 	struct xfs_attr_leaf_entry *entry;
2080 	struct xfs_attr_leaf_entry *entries;
2081 	struct xfs_attr_leaf_name_local *name_loc;
2082 	struct xfs_attr_leaf_name_remote *name_rmt;
2083 	xfs_dahash_t		hashval;
2084 	int			probe;
2085 	int			span;
2086 
2087 	trace_xfs_attr_leaf_lookup(args);
2088 
2089 	leaf = bp->b_addr;
2090 	xfs_attr3_leaf_hdr_from_disk(&ichdr, leaf);
2091 	entries = xfs_attr3_leaf_entryp(leaf);
2092 	ASSERT(ichdr.count < args->geo->blksize / 8);
2093 
2094 	/*
2095 	 * Binary search.  (note: small blocks will skip this loop)
2096 	 */
2097 	hashval = args->hashval;
2098 	probe = span = ichdr.count / 2;
2099 	for (entry = &entries[probe]; span > 4; entry = &entries[probe]) {
2100 		span /= 2;
2101 		if (be32_to_cpu(entry->hashval) < hashval)
2102 			probe += span;
2103 		else if (be32_to_cpu(entry->hashval) > hashval)
2104 			probe -= span;
2105 		else
2106 			break;
2107 	}
2108 	ASSERT(probe >= 0 && (!ichdr.count || probe < ichdr.count));
2109 	ASSERT(span <= 4 || be32_to_cpu(entry->hashval) == hashval);
2110 
2111 	/*
2112 	 * Since we may have duplicate hashval's, find the first matching
2113 	 * hashval in the leaf.
2114 	 */
2115 	while (probe > 0 && be32_to_cpu(entry->hashval) >= hashval) {
2116 		entry--;
2117 		probe--;
2118 	}
2119 	while (probe < ichdr.count &&
2120 	       be32_to_cpu(entry->hashval) < hashval) {
2121 		entry++;
2122 		probe++;
2123 	}
2124 	if (probe == ichdr.count || be32_to_cpu(entry->hashval) != hashval) {
2125 		args->index = probe;
2126 		return -ENOATTR;
2127 	}
2128 
2129 	/*
2130 	 * Duplicate keys may be present, so search all of them for a match.
2131 	 */
2132 	for (; probe < ichdr.count && (be32_to_cpu(entry->hashval) == hashval);
2133 			entry++, probe++) {
2134 /*
2135  * GROT: Add code to remove incomplete entries.
2136  */
2137 		/*
2138 		 * If we are looking for INCOMPLETE entries, show only those.
2139 		 * If we are looking for complete entries, show only those.
2140 		 */
2141 		if ((args->flags & XFS_ATTR_INCOMPLETE) !=
2142 		    (entry->flags & XFS_ATTR_INCOMPLETE)) {
2143 			continue;
2144 		}
2145 		if (entry->flags & XFS_ATTR_LOCAL) {
2146 			name_loc = xfs_attr3_leaf_name_local(leaf, probe);
2147 			if (name_loc->namelen != args->namelen)
2148 				continue;
2149 			if (memcmp(args->name, name_loc->nameval,
2150 							args->namelen) != 0)
2151 				continue;
2152 			if (!xfs_attr_namesp_match(args->flags, entry->flags))
2153 				continue;
2154 			args->index = probe;
2155 			return -EEXIST;
2156 		} else {
2157 			name_rmt = xfs_attr3_leaf_name_remote(leaf, probe);
2158 			if (name_rmt->namelen != args->namelen)
2159 				continue;
2160 			if (memcmp(args->name, name_rmt->name,
2161 							args->namelen) != 0)
2162 				continue;
2163 			if (!xfs_attr_namesp_match(args->flags, entry->flags))
2164 				continue;
2165 			args->index = probe;
2166 			args->rmtvaluelen = be32_to_cpu(name_rmt->valuelen);
2167 			args->rmtblkno = be32_to_cpu(name_rmt->valueblk);
2168 			args->rmtblkcnt = xfs_attr3_rmt_blocks(
2169 							args->dp->i_mount,
2170 							args->rmtvaluelen);
2171 			return -EEXIST;
2172 		}
2173 	}
2174 	args->index = probe;
2175 	return -ENOATTR;
2176 }
2177 
2178 /*
2179  * Get the value associated with an attribute name from a leaf attribute
2180  * list structure.
2181  */
2182 int
2183 xfs_attr3_leaf_getvalue(
2184 	struct xfs_buf		*bp,
2185 	struct xfs_da_args	*args)
2186 {
2187 	struct xfs_attr_leafblock *leaf;
2188 	struct xfs_attr3_icleaf_hdr ichdr;
2189 	struct xfs_attr_leaf_entry *entry;
2190 	struct xfs_attr_leaf_name_local *name_loc;
2191 	struct xfs_attr_leaf_name_remote *name_rmt;
2192 	int			valuelen;
2193 
2194 	leaf = bp->b_addr;
2195 	xfs_attr3_leaf_hdr_from_disk(&ichdr, leaf);
2196 	ASSERT(ichdr.count < args->geo->blksize / 8);
2197 	ASSERT(args->index < ichdr.count);
2198 
2199 	entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
2200 	if (entry->flags & XFS_ATTR_LOCAL) {
2201 		name_loc = xfs_attr3_leaf_name_local(leaf, args->index);
2202 		ASSERT(name_loc->namelen == args->namelen);
2203 		ASSERT(memcmp(args->name, name_loc->nameval, args->namelen) == 0);
2204 		valuelen = be16_to_cpu(name_loc->valuelen);
2205 		if (args->flags & ATTR_KERNOVAL) {
2206 			args->valuelen = valuelen;
2207 			return 0;
2208 		}
2209 		if (args->valuelen < valuelen) {
2210 			args->valuelen = valuelen;
2211 			return -ERANGE;
2212 		}
2213 		args->valuelen = valuelen;
2214 		memcpy(args->value, &name_loc->nameval[args->namelen], valuelen);
2215 	} else {
2216 		name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
2217 		ASSERT(name_rmt->namelen == args->namelen);
2218 		ASSERT(memcmp(args->name, name_rmt->name, args->namelen) == 0);
2219 		args->rmtvaluelen = be32_to_cpu(name_rmt->valuelen);
2220 		args->rmtblkno = be32_to_cpu(name_rmt->valueblk);
2221 		args->rmtblkcnt = xfs_attr3_rmt_blocks(args->dp->i_mount,
2222 						       args->rmtvaluelen);
2223 		if (args->flags & ATTR_KERNOVAL) {
2224 			args->valuelen = args->rmtvaluelen;
2225 			return 0;
2226 		}
2227 		if (args->valuelen < args->rmtvaluelen) {
2228 			args->valuelen = args->rmtvaluelen;
2229 			return -ERANGE;
2230 		}
2231 		args->valuelen = args->rmtvaluelen;
2232 	}
2233 	return 0;
2234 }
2235 
2236 /*========================================================================
2237  * Utility routines.
2238  *========================================================================*/
2239 
2240 /*
2241  * Move the indicated entries from one leaf to another.
2242  * NOTE: this routine modifies both source and destination leaves.
2243  */
2244 /*ARGSUSED*/
2245 STATIC void
2246 xfs_attr3_leaf_moveents(
2247 	struct xfs_da_args		*args,
2248 	struct xfs_attr_leafblock	*leaf_s,
2249 	struct xfs_attr3_icleaf_hdr	*ichdr_s,
2250 	int				start_s,
2251 	struct xfs_attr_leafblock	*leaf_d,
2252 	struct xfs_attr3_icleaf_hdr	*ichdr_d,
2253 	int				start_d,
2254 	int				count)
2255 {
2256 	struct xfs_attr_leaf_entry	*entry_s;
2257 	struct xfs_attr_leaf_entry	*entry_d;
2258 	int				desti;
2259 	int				tmp;
2260 	int				i;
2261 
2262 	/*
2263 	 * Check for nothing to do.
2264 	 */
2265 	if (count == 0)
2266 		return;
2267 
2268 	/*
2269 	 * Set up environment.
2270 	 */
2271 	ASSERT(ichdr_s->magic == XFS_ATTR_LEAF_MAGIC ||
2272 	       ichdr_s->magic == XFS_ATTR3_LEAF_MAGIC);
2273 	ASSERT(ichdr_s->magic == ichdr_d->magic);
2274 	ASSERT(ichdr_s->count > 0 && ichdr_s->count < args->geo->blksize / 8);
2275 	ASSERT(ichdr_s->firstused >= (ichdr_s->count * sizeof(*entry_s))
2276 					+ xfs_attr3_leaf_hdr_size(leaf_s));
2277 	ASSERT(ichdr_d->count < args->geo->blksize / 8);
2278 	ASSERT(ichdr_d->firstused >= (ichdr_d->count * sizeof(*entry_d))
2279 					+ xfs_attr3_leaf_hdr_size(leaf_d));
2280 
2281 	ASSERT(start_s < ichdr_s->count);
2282 	ASSERT(start_d <= ichdr_d->count);
2283 	ASSERT(count <= ichdr_s->count);
2284 
2285 
2286 	/*
2287 	 * Move the entries in the destination leaf up to make a hole?
2288 	 */
2289 	if (start_d < ichdr_d->count) {
2290 		tmp  = ichdr_d->count - start_d;
2291 		tmp *= sizeof(xfs_attr_leaf_entry_t);
2292 		entry_s = &xfs_attr3_leaf_entryp(leaf_d)[start_d];
2293 		entry_d = &xfs_attr3_leaf_entryp(leaf_d)[start_d + count];
2294 		memmove(entry_d, entry_s, tmp);
2295 	}
2296 
2297 	/*
2298 	 * Copy all entry's in the same (sorted) order,
2299 	 * but allocate attribute info packed and in sequence.
2300 	 */
2301 	entry_s = &xfs_attr3_leaf_entryp(leaf_s)[start_s];
2302 	entry_d = &xfs_attr3_leaf_entryp(leaf_d)[start_d];
2303 	desti = start_d;
2304 	for (i = 0; i < count; entry_s++, entry_d++, desti++, i++) {
2305 		ASSERT(be16_to_cpu(entry_s->nameidx) >= ichdr_s->firstused);
2306 		tmp = xfs_attr_leaf_entsize(leaf_s, start_s + i);
2307 #ifdef GROT
2308 		/*
2309 		 * Code to drop INCOMPLETE entries.  Difficult to use as we
2310 		 * may also need to change the insertion index.  Code turned
2311 		 * off for 6.2, should be revisited later.
2312 		 */
2313 		if (entry_s->flags & XFS_ATTR_INCOMPLETE) { /* skip partials? */
2314 			memset(xfs_attr3_leaf_name(leaf_s, start_s + i), 0, tmp);
2315 			ichdr_s->usedbytes -= tmp;
2316 			ichdr_s->count -= 1;
2317 			entry_d--;	/* to compensate for ++ in loop hdr */
2318 			desti--;
2319 			if ((start_s + i) < offset)
2320 				result++;	/* insertion index adjustment */
2321 		} else {
2322 #endif /* GROT */
2323 			ichdr_d->firstused -= tmp;
2324 			/* both on-disk, don't endian flip twice */
2325 			entry_d->hashval = entry_s->hashval;
2326 			entry_d->nameidx = cpu_to_be16(ichdr_d->firstused);
2327 			entry_d->flags = entry_s->flags;
2328 			ASSERT(be16_to_cpu(entry_d->nameidx) + tmp
2329 							<= args->geo->blksize);
2330 			memmove(xfs_attr3_leaf_name(leaf_d, desti),
2331 				xfs_attr3_leaf_name(leaf_s, start_s + i), tmp);
2332 			ASSERT(be16_to_cpu(entry_s->nameidx) + tmp
2333 							<= args->geo->blksize);
2334 			memset(xfs_attr3_leaf_name(leaf_s, start_s + i), 0, tmp);
2335 			ichdr_s->usedbytes -= tmp;
2336 			ichdr_d->usedbytes += tmp;
2337 			ichdr_s->count -= 1;
2338 			ichdr_d->count += 1;
2339 			tmp = ichdr_d->count * sizeof(xfs_attr_leaf_entry_t)
2340 					+ xfs_attr3_leaf_hdr_size(leaf_d);
2341 			ASSERT(ichdr_d->firstused >= tmp);
2342 #ifdef GROT
2343 		}
2344 #endif /* GROT */
2345 	}
2346 
2347 	/*
2348 	 * Zero out the entries we just copied.
2349 	 */
2350 	if (start_s == ichdr_s->count) {
2351 		tmp = count * sizeof(xfs_attr_leaf_entry_t);
2352 		entry_s = &xfs_attr3_leaf_entryp(leaf_s)[start_s];
2353 		ASSERT(((char *)entry_s + tmp) <=
2354 		       ((char *)leaf_s + args->geo->blksize));
2355 		memset(entry_s, 0, tmp);
2356 	} else {
2357 		/*
2358 		 * Move the remaining entries down to fill the hole,
2359 		 * then zero the entries at the top.
2360 		 */
2361 		tmp  = (ichdr_s->count - count) * sizeof(xfs_attr_leaf_entry_t);
2362 		entry_s = &xfs_attr3_leaf_entryp(leaf_s)[start_s + count];
2363 		entry_d = &xfs_attr3_leaf_entryp(leaf_s)[start_s];
2364 		memmove(entry_d, entry_s, tmp);
2365 
2366 		tmp = count * sizeof(xfs_attr_leaf_entry_t);
2367 		entry_s = &xfs_attr3_leaf_entryp(leaf_s)[ichdr_s->count];
2368 		ASSERT(((char *)entry_s + tmp) <=
2369 		       ((char *)leaf_s + args->geo->blksize));
2370 		memset(entry_s, 0, tmp);
2371 	}
2372 
2373 	/*
2374 	 * Fill in the freemap information
2375 	 */
2376 	ichdr_d->freemap[0].base = xfs_attr3_leaf_hdr_size(leaf_d);
2377 	ichdr_d->freemap[0].base += ichdr_d->count * sizeof(xfs_attr_leaf_entry_t);
2378 	ichdr_d->freemap[0].size = ichdr_d->firstused - ichdr_d->freemap[0].base;
2379 	ichdr_d->freemap[1].base = 0;
2380 	ichdr_d->freemap[2].base = 0;
2381 	ichdr_d->freemap[1].size = 0;
2382 	ichdr_d->freemap[2].size = 0;
2383 	ichdr_s->holes = 1;	/* leaf may not be compact */
2384 }
2385 
2386 /*
2387  * Pick up the last hashvalue from a leaf block.
2388  */
2389 xfs_dahash_t
2390 xfs_attr_leaf_lasthash(
2391 	struct xfs_buf	*bp,
2392 	int		*count)
2393 {
2394 	struct xfs_attr3_icleaf_hdr ichdr;
2395 	struct xfs_attr_leaf_entry *entries;
2396 
2397 	xfs_attr3_leaf_hdr_from_disk(&ichdr, bp->b_addr);
2398 	entries = xfs_attr3_leaf_entryp(bp->b_addr);
2399 	if (count)
2400 		*count = ichdr.count;
2401 	if (!ichdr.count)
2402 		return 0;
2403 	return be32_to_cpu(entries[ichdr.count - 1].hashval);
2404 }
2405 
2406 /*
2407  * Calculate the number of bytes used to store the indicated attribute
2408  * (whether local or remote only calculate bytes in this block).
2409  */
2410 STATIC int
2411 xfs_attr_leaf_entsize(xfs_attr_leafblock_t *leaf, int index)
2412 {
2413 	struct xfs_attr_leaf_entry *entries;
2414 	xfs_attr_leaf_name_local_t *name_loc;
2415 	xfs_attr_leaf_name_remote_t *name_rmt;
2416 	int size;
2417 
2418 	entries = xfs_attr3_leaf_entryp(leaf);
2419 	if (entries[index].flags & XFS_ATTR_LOCAL) {
2420 		name_loc = xfs_attr3_leaf_name_local(leaf, index);
2421 		size = xfs_attr_leaf_entsize_local(name_loc->namelen,
2422 						   be16_to_cpu(name_loc->valuelen));
2423 	} else {
2424 		name_rmt = xfs_attr3_leaf_name_remote(leaf, index);
2425 		size = xfs_attr_leaf_entsize_remote(name_rmt->namelen);
2426 	}
2427 	return size;
2428 }
2429 
2430 /*
2431  * Calculate the number of bytes that would be required to store the new
2432  * attribute (whether local or remote only calculate bytes in this block).
2433  * This routine decides as a side effect whether the attribute will be
2434  * a "local" or a "remote" attribute.
2435  */
2436 int
2437 xfs_attr_leaf_newentsize(
2438 	struct xfs_da_args	*args,
2439 	int			*local)
2440 {
2441 	int			size;
2442 
2443 	size = xfs_attr_leaf_entsize_local(args->namelen, args->valuelen);
2444 	if (size < xfs_attr_leaf_entsize_local_max(args->geo->blksize)) {
2445 		if (local)
2446 			*local = 1;
2447 		return size;
2448 	}
2449 	if (local)
2450 		*local = 0;
2451 	return xfs_attr_leaf_entsize_remote(args->namelen);
2452 }
2453 
2454 
2455 /*========================================================================
2456  * Manage the INCOMPLETE flag in a leaf entry
2457  *========================================================================*/
2458 
2459 /*
2460  * Clear the INCOMPLETE flag on an entry in a leaf block.
2461  */
2462 int
2463 xfs_attr3_leaf_clearflag(
2464 	struct xfs_da_args	*args)
2465 {
2466 	struct xfs_attr_leafblock *leaf;
2467 	struct xfs_attr_leaf_entry *entry;
2468 	struct xfs_attr_leaf_name_remote *name_rmt;
2469 	struct xfs_buf		*bp;
2470 	int			error;
2471 #ifdef DEBUG
2472 	struct xfs_attr3_icleaf_hdr ichdr;
2473 	xfs_attr_leaf_name_local_t *name_loc;
2474 	int namelen;
2475 	char *name;
2476 #endif /* DEBUG */
2477 
2478 	trace_xfs_attr_leaf_clearflag(args);
2479 	/*
2480 	 * Set up the operation.
2481 	 */
2482 	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
2483 	if (error)
2484 		return error;
2485 
2486 	leaf = bp->b_addr;
2487 	entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
2488 	ASSERT(entry->flags & XFS_ATTR_INCOMPLETE);
2489 
2490 #ifdef DEBUG
2491 	xfs_attr3_leaf_hdr_from_disk(&ichdr, leaf);
2492 	ASSERT(args->index < ichdr.count);
2493 	ASSERT(args->index >= 0);
2494 
2495 	if (entry->flags & XFS_ATTR_LOCAL) {
2496 		name_loc = xfs_attr3_leaf_name_local(leaf, args->index);
2497 		namelen = name_loc->namelen;
2498 		name = (char *)name_loc->nameval;
2499 	} else {
2500 		name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
2501 		namelen = name_rmt->namelen;
2502 		name = (char *)name_rmt->name;
2503 	}
2504 	ASSERT(be32_to_cpu(entry->hashval) == args->hashval);
2505 	ASSERT(namelen == args->namelen);
2506 	ASSERT(memcmp(name, args->name, namelen) == 0);
2507 #endif /* DEBUG */
2508 
2509 	entry->flags &= ~XFS_ATTR_INCOMPLETE;
2510 	xfs_trans_log_buf(args->trans, bp,
2511 			 XFS_DA_LOGRANGE(leaf, entry, sizeof(*entry)));
2512 
2513 	if (args->rmtblkno) {
2514 		ASSERT((entry->flags & XFS_ATTR_LOCAL) == 0);
2515 		name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
2516 		name_rmt->valueblk = cpu_to_be32(args->rmtblkno);
2517 		name_rmt->valuelen = cpu_to_be32(args->rmtvaluelen);
2518 		xfs_trans_log_buf(args->trans, bp,
2519 			 XFS_DA_LOGRANGE(leaf, name_rmt, sizeof(*name_rmt)));
2520 	}
2521 
2522 	/*
2523 	 * Commit the flag value change and start the next trans in series.
2524 	 */
2525 	return xfs_trans_roll(&args->trans, args->dp);
2526 }
2527 
2528 /*
2529  * Set the INCOMPLETE flag on an entry in a leaf block.
2530  */
2531 int
2532 xfs_attr3_leaf_setflag(
2533 	struct xfs_da_args	*args)
2534 {
2535 	struct xfs_attr_leafblock *leaf;
2536 	struct xfs_attr_leaf_entry *entry;
2537 	struct xfs_attr_leaf_name_remote *name_rmt;
2538 	struct xfs_buf		*bp;
2539 	int error;
2540 #ifdef DEBUG
2541 	struct xfs_attr3_icleaf_hdr ichdr;
2542 #endif
2543 
2544 	trace_xfs_attr_leaf_setflag(args);
2545 
2546 	/*
2547 	 * Set up the operation.
2548 	 */
2549 	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
2550 	if (error)
2551 		return error;
2552 
2553 	leaf = bp->b_addr;
2554 #ifdef DEBUG
2555 	xfs_attr3_leaf_hdr_from_disk(&ichdr, leaf);
2556 	ASSERT(args->index < ichdr.count);
2557 	ASSERT(args->index >= 0);
2558 #endif
2559 	entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
2560 
2561 	ASSERT((entry->flags & XFS_ATTR_INCOMPLETE) == 0);
2562 	entry->flags |= XFS_ATTR_INCOMPLETE;
2563 	xfs_trans_log_buf(args->trans, bp,
2564 			XFS_DA_LOGRANGE(leaf, entry, sizeof(*entry)));
2565 	if ((entry->flags & XFS_ATTR_LOCAL) == 0) {
2566 		name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
2567 		name_rmt->valueblk = 0;
2568 		name_rmt->valuelen = 0;
2569 		xfs_trans_log_buf(args->trans, bp,
2570 			 XFS_DA_LOGRANGE(leaf, name_rmt, sizeof(*name_rmt)));
2571 	}
2572 
2573 	/*
2574 	 * Commit the flag value change and start the next trans in series.
2575 	 */
2576 	return xfs_trans_roll(&args->trans, args->dp);
2577 }
2578 
2579 /*
2580  * In a single transaction, clear the INCOMPLETE flag on the leaf entry
2581  * given by args->blkno/index and set the INCOMPLETE flag on the leaf
2582  * entry given by args->blkno2/index2.
2583  *
2584  * Note that they could be in different blocks, or in the same block.
2585  */
2586 int
2587 xfs_attr3_leaf_flipflags(
2588 	struct xfs_da_args	*args)
2589 {
2590 	struct xfs_attr_leafblock *leaf1;
2591 	struct xfs_attr_leafblock *leaf2;
2592 	struct xfs_attr_leaf_entry *entry1;
2593 	struct xfs_attr_leaf_entry *entry2;
2594 	struct xfs_attr_leaf_name_remote *name_rmt;
2595 	struct xfs_buf		*bp1;
2596 	struct xfs_buf		*bp2;
2597 	int error;
2598 #ifdef DEBUG
2599 	struct xfs_attr3_icleaf_hdr ichdr1;
2600 	struct xfs_attr3_icleaf_hdr ichdr2;
2601 	xfs_attr_leaf_name_local_t *name_loc;
2602 	int namelen1, namelen2;
2603 	char *name1, *name2;
2604 #endif /* DEBUG */
2605 
2606 	trace_xfs_attr_leaf_flipflags(args);
2607 
2608 	/*
2609 	 * Read the block containing the "old" attr
2610 	 */
2611 	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp1);
2612 	if (error)
2613 		return error;
2614 
2615 	/*
2616 	 * Read the block containing the "new" attr, if it is different
2617 	 */
2618 	if (args->blkno2 != args->blkno) {
2619 		error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno2,
2620 					   -1, &bp2);
2621 		if (error)
2622 			return error;
2623 	} else {
2624 		bp2 = bp1;
2625 	}
2626 
2627 	leaf1 = bp1->b_addr;
2628 	entry1 = &xfs_attr3_leaf_entryp(leaf1)[args->index];
2629 
2630 	leaf2 = bp2->b_addr;
2631 	entry2 = &xfs_attr3_leaf_entryp(leaf2)[args->index2];
2632 
2633 #ifdef DEBUG
2634 	xfs_attr3_leaf_hdr_from_disk(&ichdr1, leaf1);
2635 	ASSERT(args->index < ichdr1.count);
2636 	ASSERT(args->index >= 0);
2637 
2638 	xfs_attr3_leaf_hdr_from_disk(&ichdr2, leaf2);
2639 	ASSERT(args->index2 < ichdr2.count);
2640 	ASSERT(args->index2 >= 0);
2641 
2642 	if (entry1->flags & XFS_ATTR_LOCAL) {
2643 		name_loc = xfs_attr3_leaf_name_local(leaf1, args->index);
2644 		namelen1 = name_loc->namelen;
2645 		name1 = (char *)name_loc->nameval;
2646 	} else {
2647 		name_rmt = xfs_attr3_leaf_name_remote(leaf1, args->index);
2648 		namelen1 = name_rmt->namelen;
2649 		name1 = (char *)name_rmt->name;
2650 	}
2651 	if (entry2->flags & XFS_ATTR_LOCAL) {
2652 		name_loc = xfs_attr3_leaf_name_local(leaf2, args->index2);
2653 		namelen2 = name_loc->namelen;
2654 		name2 = (char *)name_loc->nameval;
2655 	} else {
2656 		name_rmt = xfs_attr3_leaf_name_remote(leaf2, args->index2);
2657 		namelen2 = name_rmt->namelen;
2658 		name2 = (char *)name_rmt->name;
2659 	}
2660 	ASSERT(be32_to_cpu(entry1->hashval) == be32_to_cpu(entry2->hashval));
2661 	ASSERT(namelen1 == namelen2);
2662 	ASSERT(memcmp(name1, name2, namelen1) == 0);
2663 #endif /* DEBUG */
2664 
2665 	ASSERT(entry1->flags & XFS_ATTR_INCOMPLETE);
2666 	ASSERT((entry2->flags & XFS_ATTR_INCOMPLETE) == 0);
2667 
2668 	entry1->flags &= ~XFS_ATTR_INCOMPLETE;
2669 	xfs_trans_log_buf(args->trans, bp1,
2670 			  XFS_DA_LOGRANGE(leaf1, entry1, sizeof(*entry1)));
2671 	if (args->rmtblkno) {
2672 		ASSERT((entry1->flags & XFS_ATTR_LOCAL) == 0);
2673 		name_rmt = xfs_attr3_leaf_name_remote(leaf1, args->index);
2674 		name_rmt->valueblk = cpu_to_be32(args->rmtblkno);
2675 		name_rmt->valuelen = cpu_to_be32(args->rmtvaluelen);
2676 		xfs_trans_log_buf(args->trans, bp1,
2677 			 XFS_DA_LOGRANGE(leaf1, name_rmt, sizeof(*name_rmt)));
2678 	}
2679 
2680 	entry2->flags |= XFS_ATTR_INCOMPLETE;
2681 	xfs_trans_log_buf(args->trans, bp2,
2682 			  XFS_DA_LOGRANGE(leaf2, entry2, sizeof(*entry2)));
2683 	if ((entry2->flags & XFS_ATTR_LOCAL) == 0) {
2684 		name_rmt = xfs_attr3_leaf_name_remote(leaf2, args->index2);
2685 		name_rmt->valueblk = 0;
2686 		name_rmt->valuelen = 0;
2687 		xfs_trans_log_buf(args->trans, bp2,
2688 			 XFS_DA_LOGRANGE(leaf2, name_rmt, sizeof(*name_rmt)));
2689 	}
2690 
2691 	/*
2692 	 * Commit the flag value change and start the next trans in series.
2693 	 */
2694 	error = xfs_trans_roll(&args->trans, args->dp);
2695 
2696 	return error;
2697 }
2698