1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (c) 2000-2003,2005 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_mount.h"
  14#include "xfs_inode.h"
  15#include "xfs_bmap.h"
  16#include "xfs_dir2.h"
  17#include "xfs_dir2_priv.h"
  18#include "xfs_error.h"
  19#include "xfs_trace.h"
  20#include "xfs_trans.h"
  21#include "xfs_buf_item.h"
  22#include "xfs_health.h"
  23
  24/*
  25 * Local function declarations.
  26 */
  27static int xfs_dir2_leaf_lookup_int(xfs_da_args_t *args, struct xfs_buf **lbpp,
  28				    int *indexp, struct xfs_buf **dbpp,
  29				    struct xfs_dir3_icleaf_hdr *leafhdr);
  30static void xfs_dir3_leaf_log_bests(struct xfs_da_args *args,
  31				    struct xfs_buf *bp, int first, int last);
  32static void xfs_dir3_leaf_log_tail(struct xfs_da_args *args,
  33				   struct xfs_buf *bp);
  34
  35void
  36xfs_dir2_leaf_hdr_from_disk(
  37	struct xfs_mount		*mp,
  38	struct xfs_dir3_icleaf_hdr	*to,
  39	struct xfs_dir2_leaf		*from)
  40{
  41	if (xfs_has_crc(mp)) {
  42		struct xfs_dir3_leaf *from3 = (struct xfs_dir3_leaf *)from;
  43
  44		to->forw = be32_to_cpu(from3->hdr.info.hdr.forw);
  45		to->back = be32_to_cpu(from3->hdr.info.hdr.back);
  46		to->magic = be16_to_cpu(from3->hdr.info.hdr.magic);
  47		to->count = be16_to_cpu(from3->hdr.count);
  48		to->stale = be16_to_cpu(from3->hdr.stale);
  49		to->ents = from3->__ents;
  50
  51		ASSERT(to->magic == XFS_DIR3_LEAF1_MAGIC ||
  52		       to->magic == XFS_DIR3_LEAFN_MAGIC);
  53	} else {
  54		to->forw = be32_to_cpu(from->hdr.info.forw);
  55		to->back = be32_to_cpu(from->hdr.info.back);
  56		to->magic = be16_to_cpu(from->hdr.info.magic);
  57		to->count = be16_to_cpu(from->hdr.count);
  58		to->stale = be16_to_cpu(from->hdr.stale);
  59		to->ents = from->__ents;
  60
  61		ASSERT(to->magic == XFS_DIR2_LEAF1_MAGIC ||
  62		       to->magic == XFS_DIR2_LEAFN_MAGIC);
  63	}
  64}
  65
  66void
  67xfs_dir2_leaf_hdr_to_disk(
  68	struct xfs_mount		*mp,
  69	struct xfs_dir2_leaf		*to,
  70	struct xfs_dir3_icleaf_hdr	*from)
  71{
  72	if (xfs_has_crc(mp)) {
  73		struct xfs_dir3_leaf *to3 = (struct xfs_dir3_leaf *)to;
  74
  75		ASSERT(from->magic == XFS_DIR3_LEAF1_MAGIC ||
  76		       from->magic == XFS_DIR3_LEAFN_MAGIC);
  77
  78		to3->hdr.info.hdr.forw = cpu_to_be32(from->forw);
  79		to3->hdr.info.hdr.back = cpu_to_be32(from->back);
  80		to3->hdr.info.hdr.magic = cpu_to_be16(from->magic);
  81		to3->hdr.count = cpu_to_be16(from->count);
  82		to3->hdr.stale = cpu_to_be16(from->stale);
  83	} else {
  84		ASSERT(from->magic == XFS_DIR2_LEAF1_MAGIC ||
  85		       from->magic == XFS_DIR2_LEAFN_MAGIC);
  86
  87		to->hdr.info.forw = cpu_to_be32(from->forw);
  88		to->hdr.info.back = cpu_to_be32(from->back);
  89		to->hdr.info.magic = cpu_to_be16(from->magic);
  90		to->hdr.count = cpu_to_be16(from->count);
  91		to->hdr.stale = cpu_to_be16(from->stale);
  92	}
  93}
  94
  95/*
  96 * Check the internal consistency of a leaf1 block.
  97 * Pop an assert if something is wrong.
  98 */
  99#ifdef DEBUG
 100static xfs_failaddr_t
 101xfs_dir3_leaf1_check(
 102	struct xfs_inode	*dp,
 103	struct xfs_buf		*bp)
 104{
 105	struct xfs_dir2_leaf	*leaf = bp->b_addr;
 106	struct xfs_dir3_icleaf_hdr leafhdr;
 107
 108	xfs_dir2_leaf_hdr_from_disk(dp->i_mount, &leafhdr, leaf);
 109
 110	if (leafhdr.magic == XFS_DIR3_LEAF1_MAGIC) {
 111		struct xfs_dir3_leaf_hdr *leaf3 = bp->b_addr;
 112		if (be64_to_cpu(leaf3->info.blkno) != xfs_buf_daddr(bp))
 113			return __this_address;
 114	} else if (leafhdr.magic != XFS_DIR2_LEAF1_MAGIC)
 115		return __this_address;
 116
 117	return xfs_dir3_leaf_check_int(dp->i_mount, &leafhdr, leaf, false);
 118}
 119
 120static inline void
 121xfs_dir3_leaf_check(
 122	struct xfs_inode	*dp,
 123	struct xfs_buf		*bp)
 124{
 125	xfs_failaddr_t		fa;
 126
 127	fa = xfs_dir3_leaf1_check(dp, bp);
 128	if (!fa)
 129		return;
 130	xfs_corruption_error(__func__, XFS_ERRLEVEL_LOW, dp->i_mount,
 131			bp->b_addr, BBTOB(bp->b_length), __FILE__, __LINE__,
 132			fa);
 133	ASSERT(0);
 134}
 135#else
 136#define	xfs_dir3_leaf_check(dp, bp)
 137#endif
 138
 139xfs_failaddr_t
 140xfs_dir3_leaf_check_int(
 141	struct xfs_mount		*mp,
 142	struct xfs_dir3_icleaf_hdr	*hdr,
 143	struct xfs_dir2_leaf		*leaf,
 144	bool				expensive_checking)
 145{
 146	struct xfs_da_geometry		*geo = mp->m_dir_geo;
 147	xfs_dir2_leaf_tail_t		*ltp;
 148	int				stale;
 149	int				i;
 150	bool				isleaf1 = (hdr->magic == XFS_DIR2_LEAF1_MAGIC ||
 151						   hdr->magic == XFS_DIR3_LEAF1_MAGIC);
 152
 153	ltp = xfs_dir2_leaf_tail_p(geo, leaf);
 154
 155	/*
 156	 * XXX (dgc): This value is not restrictive enough.
 157	 * Should factor in the size of the bests table as well.
 158	 * We can deduce a value for that from i_disk_size.
 159	 */
 160	if (hdr->count > geo->leaf_max_ents)
 161		return __this_address;
 162
 163	/* Leaves and bests don't overlap in leaf format. */
 164	if (isleaf1 &&
 
 165	    (char *)&hdr->ents[hdr->count] > (char *)xfs_dir2_leaf_bests_p(ltp))
 166		return __this_address;
 167
 168	if (!expensive_checking)
 169		return NULL;
 170
 171	/* Check hash value order, count stale entries.  */
 172	for (i = stale = 0; i < hdr->count; i++) {
 173		if (i + 1 < hdr->count) {
 174			if (be32_to_cpu(hdr->ents[i].hashval) >
 175					be32_to_cpu(hdr->ents[i + 1].hashval))
 176				return __this_address;
 177		}
 178		if (hdr->ents[i].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 179			stale++;
 180		if (isleaf1 && xfs_dir2_dataptr_to_db(geo,
 181				be32_to_cpu(hdr->ents[i].address)) >=
 182				be32_to_cpu(ltp->bestcount))
 183			return __this_address;
 184	}
 185	if (hdr->stale != stale)
 186		return __this_address;
 187	return NULL;
 188}
 189
 190/*
 191 * We verify the magic numbers before decoding the leaf header so that on debug
 192 * kernels we don't get assertion failures in xfs_dir3_leaf_hdr_from_disk() due
 193 * to incorrect magic numbers.
 194 */
 195static xfs_failaddr_t
 196xfs_dir3_leaf_verify(
 197	struct xfs_buf			*bp)
 198{
 199	struct xfs_mount		*mp = bp->b_mount;
 200	struct xfs_dir3_icleaf_hdr	leafhdr;
 201	xfs_failaddr_t			fa;
 202
 203	fa = xfs_da3_blkinfo_verify(bp, bp->b_addr);
 204	if (fa)
 205		return fa;
 206
 207	xfs_dir2_leaf_hdr_from_disk(mp, &leafhdr, bp->b_addr);
 208	return xfs_dir3_leaf_check_int(mp, &leafhdr, bp->b_addr, true);
 209}
 210
 211xfs_failaddr_t
 212xfs_dir3_leaf_header_check(
 213	struct xfs_buf		*bp,
 214	xfs_ino_t		owner)
 215{
 216	struct xfs_mount	*mp = bp->b_mount;
 217
 218	if (xfs_has_crc(mp)) {
 219		struct xfs_dir3_leaf *hdr3 = bp->b_addr;
 220
 221		if (hdr3->hdr.info.hdr.magic !=
 222					cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) &&
 223		    hdr3->hdr.info.hdr.magic !=
 224					cpu_to_be16(XFS_DIR3_LEAFN_MAGIC))
 225			return __this_address;
 226
 227		if (be64_to_cpu(hdr3->hdr.info.owner) != owner)
 228			return __this_address;
 229	}
 230
 231	return NULL;
 232}
 233
 234static void
 235xfs_dir3_leaf_read_verify(
 236	struct xfs_buf  *bp)
 237{
 238	struct xfs_mount	*mp = bp->b_mount;
 239	xfs_failaddr_t		fa;
 240
 241	if (xfs_has_crc(mp) &&
 242	     !xfs_buf_verify_cksum(bp, XFS_DIR3_LEAF_CRC_OFF))
 243		xfs_verifier_error(bp, -EFSBADCRC, __this_address);
 244	else {
 245		fa = xfs_dir3_leaf_verify(bp);
 246		if (fa)
 247			xfs_verifier_error(bp, -EFSCORRUPTED, fa);
 248	}
 249}
 250
 251static void
 252xfs_dir3_leaf_write_verify(
 253	struct xfs_buf  *bp)
 254{
 255	struct xfs_mount	*mp = bp->b_mount;
 256	struct xfs_buf_log_item	*bip = bp->b_log_item;
 257	struct xfs_dir3_leaf_hdr *hdr3 = bp->b_addr;
 258	xfs_failaddr_t		fa;
 259
 260	fa = xfs_dir3_leaf_verify(bp);
 261	if (fa) {
 262		xfs_verifier_error(bp, -EFSCORRUPTED, fa);
 263		return;
 264	}
 265
 266	if (!xfs_has_crc(mp))
 267		return;
 268
 269	if (bip)
 270		hdr3->info.lsn = cpu_to_be64(bip->bli_item.li_lsn);
 271
 272	xfs_buf_update_cksum(bp, XFS_DIR3_LEAF_CRC_OFF);
 273}
 274
 275const struct xfs_buf_ops xfs_dir3_leaf1_buf_ops = {
 276	.name = "xfs_dir3_leaf1",
 277	.magic16 = { cpu_to_be16(XFS_DIR2_LEAF1_MAGIC),
 278		     cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) },
 279	.verify_read = xfs_dir3_leaf_read_verify,
 280	.verify_write = xfs_dir3_leaf_write_verify,
 281	.verify_struct = xfs_dir3_leaf_verify,
 282};
 283
 284const struct xfs_buf_ops xfs_dir3_leafn_buf_ops = {
 285	.name = "xfs_dir3_leafn",
 286	.magic16 = { cpu_to_be16(XFS_DIR2_LEAFN_MAGIC),
 287		     cpu_to_be16(XFS_DIR3_LEAFN_MAGIC) },
 288	.verify_read = xfs_dir3_leaf_read_verify,
 289	.verify_write = xfs_dir3_leaf_write_verify,
 290	.verify_struct = xfs_dir3_leaf_verify,
 291};
 292
 293int
 294xfs_dir3_leaf_read(
 295	struct xfs_trans	*tp,
 296	struct xfs_inode	*dp,
 297	xfs_ino_t		owner,
 298	xfs_dablk_t		fbno,
 299	struct xfs_buf		**bpp)
 300{
 301	xfs_failaddr_t		fa;
 302	int			err;
 303
 304	err = xfs_da_read_buf(tp, dp, fbno, 0, bpp, XFS_DATA_FORK,
 305			&xfs_dir3_leaf1_buf_ops);
 306	if (err || !(*bpp))
 307		return err;
 308
 309	fa = xfs_dir3_leaf_header_check(*bpp, owner);
 310	if (fa) {
 311		__xfs_buf_mark_corrupt(*bpp, fa);
 312		xfs_trans_brelse(tp, *bpp);
 313		*bpp = NULL;
 314		xfs_dirattr_mark_sick(dp, XFS_DATA_FORK);
 315		return -EFSCORRUPTED;
 316	}
 317
 318	if (tp)
 319		xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_LEAF1_BUF);
 320	return 0;
 321}
 322
 323int
 324xfs_dir3_leafn_read(
 325	struct xfs_trans	*tp,
 326	struct xfs_inode	*dp,
 327	xfs_ino_t		owner,
 328	xfs_dablk_t		fbno,
 329	struct xfs_buf		**bpp)
 330{
 331	xfs_failaddr_t		fa;
 332	int			err;
 333
 334	err = xfs_da_read_buf(tp, dp, fbno, 0, bpp, XFS_DATA_FORK,
 335			&xfs_dir3_leafn_buf_ops);
 336	if (err || !(*bpp))
 337		return err;
 338
 339	fa = xfs_dir3_leaf_header_check(*bpp, owner);
 340	if (fa) {
 341		__xfs_buf_mark_corrupt(*bpp, fa);
 342		xfs_trans_brelse(tp, *bpp);
 343		*bpp = NULL;
 344		xfs_dirattr_mark_sick(dp, XFS_DATA_FORK);
 345		return -EFSCORRUPTED;
 346	}
 347
 348	if (tp)
 349		xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_LEAFN_BUF);
 350	return 0;
 351}
 352
 353/*
 354 * Initialize a new leaf block, leaf1 or leafn magic accepted.
 355 */
 356static void
 357xfs_dir3_leaf_init(
 358	struct xfs_da_args	*args,
 
 359	struct xfs_buf		*bp,
 
 360	uint16_t		type)
 361{
 362	struct xfs_mount	*mp = args->dp->i_mount;
 363	struct xfs_trans	*tp = args->trans;
 364	struct xfs_dir2_leaf	*leaf = bp->b_addr;
 365
 366	ASSERT(type == XFS_DIR2_LEAF1_MAGIC || type == XFS_DIR2_LEAFN_MAGIC);
 367
 368	if (xfs_has_crc(mp)) {
 369		struct xfs_dir3_leaf_hdr *leaf3 = bp->b_addr;
 370
 371		memset(leaf3, 0, sizeof(*leaf3));
 372
 373		leaf3->info.hdr.magic = (type == XFS_DIR2_LEAF1_MAGIC)
 374					 ? cpu_to_be16(XFS_DIR3_LEAF1_MAGIC)
 375					 : cpu_to_be16(XFS_DIR3_LEAFN_MAGIC);
 376		leaf3->info.blkno = cpu_to_be64(xfs_buf_daddr(bp));
 377		leaf3->info.owner = cpu_to_be64(args->owner);
 378		uuid_copy(&leaf3->info.uuid, &mp->m_sb.sb_meta_uuid);
 379	} else {
 380		memset(leaf, 0, sizeof(*leaf));
 381		leaf->hdr.info.magic = cpu_to_be16(type);
 382	}
 383
 384	/*
 385	 * If it's a leaf-format directory initialize the tail.
 386	 * Caller is responsible for initialising the bests table.
 387	 */
 388	if (type == XFS_DIR2_LEAF1_MAGIC) {
 389		struct xfs_dir2_leaf_tail *ltp;
 390
 391		ltp = xfs_dir2_leaf_tail_p(mp->m_dir_geo, leaf);
 392		ltp->bestcount = 0;
 393		bp->b_ops = &xfs_dir3_leaf1_buf_ops;
 394		xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_LEAF1_BUF);
 395	} else {
 396		bp->b_ops = &xfs_dir3_leafn_buf_ops;
 397		xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_LEAFN_BUF);
 398	}
 399}
 400
 401int
 402xfs_dir3_leaf_get_buf(
 403	xfs_da_args_t		*args,
 404	xfs_dir2_db_t		bno,
 405	struct xfs_buf		**bpp,
 406	uint16_t		magic)
 407{
 408	struct xfs_inode	*dp = args->dp;
 409	struct xfs_trans	*tp = args->trans;
 
 410	struct xfs_buf		*bp;
 411	int			error;
 412
 413	ASSERT(magic == XFS_DIR2_LEAF1_MAGIC || magic == XFS_DIR2_LEAFN_MAGIC);
 414	ASSERT(bno >= xfs_dir2_byte_to_db(args->geo, XFS_DIR2_LEAF_OFFSET) &&
 415	       bno < xfs_dir2_byte_to_db(args->geo, XFS_DIR2_FREE_OFFSET));
 416
 417	error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(args->geo, bno),
 418			       &bp, XFS_DATA_FORK);
 419	if (error)
 420		return error;
 421
 422	xfs_dir3_leaf_init(args, bp, magic);
 423	xfs_dir3_leaf_log_header(args, bp);
 424	if (magic == XFS_DIR2_LEAF1_MAGIC)
 425		xfs_dir3_leaf_log_tail(args, bp);
 426	*bpp = bp;
 427	return 0;
 428}
 429
 430/*
 431 * Convert a block form directory to a leaf form directory.
 432 */
 433int						/* error */
 434xfs_dir2_block_to_leaf(
 435	xfs_da_args_t		*args,		/* operation arguments */
 436	struct xfs_buf		*dbp)		/* input block's buffer */
 437{
 438	__be16			*bestsp;	/* leaf's bestsp entries */
 439	xfs_dablk_t		blkno;		/* leaf block's bno */
 440	xfs_dir2_data_hdr_t	*hdr;		/* block header */
 441	xfs_dir2_leaf_entry_t	*blp;		/* block's leaf entries */
 442	xfs_dir2_block_tail_t	*btp;		/* block's tail */
 443	xfs_inode_t		*dp;		/* incore directory inode */
 444	int			error;		/* error return code */
 445	struct xfs_buf		*lbp;		/* leaf block's buffer */
 446	xfs_dir2_db_t		ldb;		/* leaf block's bno */
 447	xfs_dir2_leaf_t		*leaf;		/* leaf structure */
 448	xfs_dir2_leaf_tail_t	*ltp;		/* leaf's tail */
 449	int			needlog;	/* need to log block header */
 450	int			needscan;	/* need to rescan bestfree */
 451	xfs_trans_t		*tp;		/* transaction pointer */
 452	struct xfs_dir2_data_free *bf;
 453	struct xfs_dir3_icleaf_hdr leafhdr;
 454
 455	trace_xfs_dir2_block_to_leaf(args);
 456
 457	dp = args->dp;
 458	tp = args->trans;
 459	/*
 460	 * Add the leaf block to the inode.
 461	 * This interface will only put blocks in the leaf/node range.
 462	 * Since that's empty now, we'll get the root (block 0 in range).
 463	 */
 464	if ((error = xfs_da_grow_inode(args, &blkno))) {
 465		return error;
 466	}
 467	ldb = xfs_dir2_da_to_db(args->geo, blkno);
 468	ASSERT(ldb == xfs_dir2_byte_to_db(args->geo, XFS_DIR2_LEAF_OFFSET));
 469	/*
 470	 * Initialize the leaf block, get a buffer for it.
 471	 */
 472	error = xfs_dir3_leaf_get_buf(args, ldb, &lbp, XFS_DIR2_LEAF1_MAGIC);
 473	if (error)
 474		return error;
 475
 476	leaf = lbp->b_addr;
 477	hdr = dbp->b_addr;
 478	xfs_dir3_data_check(dp, dbp);
 479	btp = xfs_dir2_block_tail_p(args->geo, hdr);
 480	blp = xfs_dir2_block_leaf_p(btp);
 481	bf = xfs_dir2_data_bestfree_p(dp->i_mount, hdr);
 482
 483	/*
 484	 * Set the counts in the leaf header.
 485	 */
 486	xfs_dir2_leaf_hdr_from_disk(dp->i_mount, &leafhdr, leaf);
 487	leafhdr.count = be32_to_cpu(btp->count);
 488	leafhdr.stale = be32_to_cpu(btp->stale);
 489	xfs_dir2_leaf_hdr_to_disk(dp->i_mount, leaf, &leafhdr);
 490	xfs_dir3_leaf_log_header(args, lbp);
 491
 492	/*
 493	 * Could compact these but I think we always do the conversion
 494	 * after squeezing out stale entries.
 495	 */
 496	memcpy(leafhdr.ents, blp,
 497		be32_to_cpu(btp->count) * sizeof(struct xfs_dir2_leaf_entry));
 498	xfs_dir3_leaf_log_ents(args, &leafhdr, lbp, 0, leafhdr.count - 1);
 499	needscan = 0;
 500	needlog = 1;
 501	/*
 502	 * Make the space formerly occupied by the leaf entries and block
 503	 * tail be free.
 504	 */
 505	xfs_dir2_data_make_free(args, dbp,
 506		(xfs_dir2_data_aoff_t)((char *)blp - (char *)hdr),
 507		(xfs_dir2_data_aoff_t)((char *)hdr + args->geo->blksize -
 508				       (char *)blp),
 509		&needlog, &needscan);
 510	/*
 511	 * Fix up the block header, make it a data block.
 512	 */
 513	dbp->b_ops = &xfs_dir3_data_buf_ops;
 514	xfs_trans_buf_set_type(tp, dbp, XFS_BLFT_DIR_DATA_BUF);
 515	if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC))
 516		hdr->magic = cpu_to_be32(XFS_DIR2_DATA_MAGIC);
 517	else
 518		hdr->magic = cpu_to_be32(XFS_DIR3_DATA_MAGIC);
 519
 520	if (needscan)
 521		xfs_dir2_data_freescan(dp->i_mount, hdr, &needlog);
 522	/*
 523	 * Set up leaf tail and bests table.
 524	 */
 525	ltp = xfs_dir2_leaf_tail_p(args->geo, leaf);
 526	ltp->bestcount = cpu_to_be32(1);
 527	bestsp = xfs_dir2_leaf_bests_p(ltp);
 528	bestsp[0] =  bf[0].length;
 529	/*
 530	 * Log the data header and leaf bests table.
 531	 */
 532	if (needlog)
 533		xfs_dir2_data_log_header(args, dbp);
 534	xfs_dir3_leaf_check(dp, lbp);
 535	xfs_dir3_data_check(dp, dbp);
 536	xfs_dir3_leaf_log_bests(args, lbp, 0, 0);
 537	return 0;
 538}
 539
 540STATIC void
 541xfs_dir3_leaf_find_stale(
 542	struct xfs_dir3_icleaf_hdr *leafhdr,
 543	struct xfs_dir2_leaf_entry *ents,
 544	int			index,
 545	int			*lowstale,
 546	int			*highstale)
 547{
 548	/*
 549	 * Find the first stale entry before our index, if any.
 550	 */
 551	for (*lowstale = index - 1; *lowstale >= 0; --*lowstale) {
 552		if (ents[*lowstale].address ==
 553		    cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 554			break;
 555	}
 556
 557	/*
 558	 * Find the first stale entry at or after our index, if any.
 559	 * Stop if the result would require moving more entries than using
 560	 * lowstale.
 561	 */
 562	for (*highstale = index; *highstale < leafhdr->count; ++*highstale) {
 563		if (ents[*highstale].address ==
 564		    cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 565			break;
 566		if (*lowstale >= 0 && index - *lowstale <= *highstale - index)
 567			break;
 568	}
 569}
 570
 571struct xfs_dir2_leaf_entry *
 572xfs_dir3_leaf_find_entry(
 573	struct xfs_dir3_icleaf_hdr *leafhdr,
 574	struct xfs_dir2_leaf_entry *ents,
 575	int			index,		/* leaf table position */
 576	int			compact,	/* need to compact leaves */
 577	int			lowstale,	/* index of prev stale leaf */
 578	int			highstale,	/* index of next stale leaf */
 579	int			*lfloglow,	/* low leaf logging index */
 580	int			*lfloghigh)	/* high leaf logging index */
 581{
 582	if (!leafhdr->stale) {
 583		xfs_dir2_leaf_entry_t	*lep;	/* leaf entry table pointer */
 584
 585		/*
 586		 * Now we need to make room to insert the leaf entry.
 587		 *
 588		 * If there are no stale entries, just insert a hole at index.
 589		 */
 590		lep = &ents[index];
 591		if (index < leafhdr->count)
 592			memmove(lep + 1, lep,
 593				(leafhdr->count - index) * sizeof(*lep));
 594
 595		/*
 596		 * Record low and high logging indices for the leaf.
 597		 */
 598		*lfloglow = index;
 599		*lfloghigh = leafhdr->count++;
 600		return lep;
 601	}
 602
 603	/*
 604	 * There are stale entries.
 605	 *
 606	 * We will use one of them for the new entry.  It's probably not at
 607	 * the right location, so we'll have to shift some up or down first.
 608	 *
 609	 * If we didn't compact before, we need to find the nearest stale
 610	 * entries before and after our insertion point.
 611	 */
 612	if (compact == 0)
 613		xfs_dir3_leaf_find_stale(leafhdr, ents, index,
 614					 &lowstale, &highstale);
 615
 616	/*
 617	 * If the low one is better, use it.
 618	 */
 619	if (lowstale >= 0 &&
 620	    (highstale == leafhdr->count ||
 621	     index - lowstale - 1 < highstale - index)) {
 622		ASSERT(index - lowstale - 1 >= 0);
 623		ASSERT(ents[lowstale].address ==
 624		       cpu_to_be32(XFS_DIR2_NULL_DATAPTR));
 625
 626		/*
 627		 * Copy entries up to cover the stale entry and make room
 628		 * for the new entry.
 629		 */
 630		if (index - lowstale - 1 > 0) {
 631			memmove(&ents[lowstale], &ents[lowstale + 1],
 632				(index - lowstale - 1) *
 633					sizeof(xfs_dir2_leaf_entry_t));
 634		}
 635		*lfloglow = min(lowstale, *lfloglow);
 636		*lfloghigh = max(index - 1, *lfloghigh);
 637		leafhdr->stale--;
 638		return &ents[index - 1];
 639	}
 640
 641	/*
 642	 * The high one is better, so use that one.
 643	 */
 644	ASSERT(highstale - index >= 0);
 645	ASSERT(ents[highstale].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR));
 646
 647	/*
 648	 * Copy entries down to cover the stale entry and make room for the
 649	 * new entry.
 650	 */
 651	if (highstale - index > 0) {
 652		memmove(&ents[index + 1], &ents[index],
 653			(highstale - index) * sizeof(xfs_dir2_leaf_entry_t));
 654	}
 655	*lfloglow = min(index, *lfloglow);
 656	*lfloghigh = max(highstale, *lfloghigh);
 657	leafhdr->stale--;
 658	return &ents[index];
 659}
 660
 661/*
 662 * Add an entry to a leaf form directory.
 663 */
 664int						/* error */
 665xfs_dir2_leaf_addname(
 666	struct xfs_da_args	*args)		/* operation arguments */
 667{
 668	struct xfs_dir3_icleaf_hdr leafhdr;
 669	struct xfs_trans	*tp = args->trans;
 670	__be16			*bestsp;	/* freespace table in leaf */
 671	__be16			*tagp;		/* end of data entry */
 672	struct xfs_buf		*dbp;		/* data block buffer */
 673	struct xfs_buf		*lbp;		/* leaf's buffer */
 674	struct xfs_dir2_leaf	*leaf;		/* leaf structure */
 675	struct xfs_inode	*dp = args->dp;	/* incore directory inode */
 676	struct xfs_dir2_data_hdr *hdr;		/* data block header */
 677	struct xfs_dir2_data_entry *dep;	/* data block entry */
 678	struct xfs_dir2_leaf_entry *lep;	/* leaf entry table pointer */
 679	struct xfs_dir2_leaf_entry *ents;
 680	struct xfs_dir2_data_unused *dup;	/* data unused entry */
 681	struct xfs_dir2_leaf_tail *ltp;		/* leaf tail pointer */
 682	struct xfs_dir2_data_free *bf;		/* bestfree table */
 683	int			compact;	/* need to compact leaves */
 684	int			error;		/* error return value */
 685	int			grown;		/* allocated new data block */
 686	int			highstale = 0;	/* index of next stale leaf */
 687	int			i;		/* temporary, index */
 688	int			index;		/* leaf table position */
 689	int			length;		/* length of new entry */
 690	int			lfloglow;	/* low leaf logging index */
 691	int			lfloghigh;	/* high leaf logging index */
 692	int			lowstale = 0;	/* index of prev stale leaf */
 693	int			needbytes;	/* leaf block bytes needed */
 694	int			needlog;	/* need to log data header */
 695	int			needscan;	/* need to rescan data free */
 696	xfs_dir2_db_t		use_block;	/* data block number */
 697
 698	trace_xfs_dir2_leaf_addname(args);
 699
 700	error = xfs_dir3_leaf_read(tp, dp, args->owner, args->geo->leafblk,
 701			&lbp);
 702	if (error)
 703		return error;
 704
 705	/*
 706	 * Look up the entry by hash value and name.
 707	 * We know it's not there, our caller has already done a lookup.
 708	 * So the index is of the entry to insert in front of.
 709	 * But if there are dup hash values the index is of the first of those.
 710	 */
 711	index = xfs_dir2_leaf_search_hash(args, lbp);
 712	leaf = lbp->b_addr;
 713	ltp = xfs_dir2_leaf_tail_p(args->geo, leaf);
 714	xfs_dir2_leaf_hdr_from_disk(dp->i_mount, &leafhdr, leaf);
 715	ents = leafhdr.ents;
 716	bestsp = xfs_dir2_leaf_bests_p(ltp);
 717	length = xfs_dir2_data_entsize(dp->i_mount, args->namelen);
 718
 719	/*
 720	 * See if there are any entries with the same hash value
 721	 * and space in their block for the new entry.
 722	 * This is good because it puts multiple same-hash value entries
 723	 * in a data block, improving the lookup of those entries.
 724	 */
 725	for (use_block = -1, lep = &ents[index];
 726	     index < leafhdr.count && be32_to_cpu(lep->hashval) == args->hashval;
 727	     index++, lep++) {
 728		if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
 729			continue;
 730		i = xfs_dir2_dataptr_to_db(args->geo, be32_to_cpu(lep->address));
 731		ASSERT(i < be32_to_cpu(ltp->bestcount));
 732		ASSERT(bestsp[i] != cpu_to_be16(NULLDATAOFF));
 733		if (be16_to_cpu(bestsp[i]) >= length) {
 734			use_block = i;
 735			break;
 736		}
 737	}
 738	/*
 739	 * Didn't find a block yet, linear search all the data blocks.
 740	 */
 741	if (use_block == -1) {
 742		for (i = 0; i < be32_to_cpu(ltp->bestcount); i++) {
 743			/*
 744			 * Remember a block we see that's missing.
 745			 */
 746			if (bestsp[i] == cpu_to_be16(NULLDATAOFF) &&
 747			    use_block == -1)
 748				use_block = i;
 749			else if (be16_to_cpu(bestsp[i]) >= length) {
 750				use_block = i;
 751				break;
 752			}
 753		}
 754	}
 755	/*
 756	 * How many bytes do we need in the leaf block?
 757	 */
 758	needbytes = 0;
 759	if (!leafhdr.stale)
 760		needbytes += sizeof(xfs_dir2_leaf_entry_t);
 761	if (use_block == -1)
 762		needbytes += sizeof(xfs_dir2_data_off_t);
 763
 764	/*
 765	 * Now kill use_block if it refers to a missing block, so we
 766	 * can use it as an indication of allocation needed.
 767	 */
 768	if (use_block != -1 && bestsp[use_block] == cpu_to_be16(NULLDATAOFF))
 769		use_block = -1;
 770	/*
 771	 * If we don't have enough free bytes but we can make enough
 772	 * by compacting out stale entries, we'll do that.
 773	 */
 774	if ((char *)bestsp - (char *)&ents[leafhdr.count] < needbytes &&
 775	    leafhdr.stale > 1)
 776		compact = 1;
 777
 778	/*
 779	 * Otherwise if we don't have enough free bytes we need to
 780	 * convert to node form.
 781	 */
 782	else if ((char *)bestsp - (char *)&ents[leafhdr.count] < needbytes) {
 783		/*
 784		 * Just checking or no space reservation, give up.
 785		 */
 786		if ((args->op_flags & XFS_DA_OP_JUSTCHECK) ||
 787							args->total == 0) {
 788			xfs_trans_brelse(tp, lbp);
 789			return -ENOSPC;
 790		}
 791		/*
 792		 * Convert to node form.
 793		 */
 794		error = xfs_dir2_leaf_to_node(args, lbp);
 795		if (error)
 796			return error;
 797		/*
 798		 * Then add the new entry.
 799		 */
 800		return xfs_dir2_node_addname(args);
 801	}
 802	/*
 803	 * Otherwise it will fit without compaction.
 804	 */
 805	else
 806		compact = 0;
 807	/*
 808	 * If just checking, then it will fit unless we needed to allocate
 809	 * a new data block.
 810	 */
 811	if (args->op_flags & XFS_DA_OP_JUSTCHECK) {
 812		xfs_trans_brelse(tp, lbp);
 813		return use_block == -1 ? -ENOSPC : 0;
 814	}
 815	/*
 816	 * If no allocations are allowed, return now before we've
 817	 * changed anything.
 818	 */
 819	if (args->total == 0 && use_block == -1) {
 820		xfs_trans_brelse(tp, lbp);
 821		return -ENOSPC;
 822	}
 823	/*
 824	 * Need to compact the leaf entries, removing stale ones.
 825	 * Leave one stale entry behind - the one closest to our
 826	 * insertion index - and we'll shift that one to our insertion
 827	 * point later.
 828	 */
 829	if (compact) {
 830		xfs_dir3_leaf_compact_x1(&leafhdr, ents, &index, &lowstale,
 831			&highstale, &lfloglow, &lfloghigh);
 832	}
 833	/*
 834	 * There are stale entries, so we'll need log-low and log-high
 835	 * impossibly bad values later.
 836	 */
 837	else if (leafhdr.stale) {
 838		lfloglow = leafhdr.count;
 839		lfloghigh = -1;
 840	}
 841	/*
 842	 * If there was no data block space found, we need to allocate
 843	 * a new one.
 844	 */
 845	if (use_block == -1) {
 846		/*
 847		 * Add the new data block.
 848		 */
 849		if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_DATA_SPACE,
 850				&use_block))) {
 851			xfs_trans_brelse(tp, lbp);
 852			return error;
 853		}
 854		/*
 855		 * Initialize the block.
 856		 */
 857		if ((error = xfs_dir3_data_init(args, use_block, &dbp))) {
 858			xfs_trans_brelse(tp, lbp);
 859			return error;
 860		}
 861		/*
 862		 * If we're adding a new data block on the end we need to
 863		 * extend the bests table.  Copy it up one entry.
 864		 */
 865		if (use_block >= be32_to_cpu(ltp->bestcount)) {
 866			bestsp--;
 867			memmove(&bestsp[0], &bestsp[1],
 868				be32_to_cpu(ltp->bestcount) * sizeof(bestsp[0]));
 869			be32_add_cpu(&ltp->bestcount, 1);
 870			xfs_dir3_leaf_log_tail(args, lbp);
 871			xfs_dir3_leaf_log_bests(args, lbp, 0,
 872						be32_to_cpu(ltp->bestcount) - 1);
 873		}
 874		/*
 875		 * If we're filling in a previously empty block just log it.
 876		 */
 877		else
 878			xfs_dir3_leaf_log_bests(args, lbp, use_block, use_block);
 879		hdr = dbp->b_addr;
 880		bf = xfs_dir2_data_bestfree_p(dp->i_mount, hdr);
 881		bestsp[use_block] = bf[0].length;
 882		grown = 1;
 883	} else {
 884		/*
 885		 * Already had space in some data block.
 886		 * Just read that one in.
 887		 */
 888		error = xfs_dir3_data_read(tp, dp, args->owner,
 889				xfs_dir2_db_to_da(args->geo, use_block), 0,
 890				&dbp);
 891		if (error) {
 892			xfs_trans_brelse(tp, lbp);
 893			return error;
 894		}
 895		hdr = dbp->b_addr;
 896		bf = xfs_dir2_data_bestfree_p(dp->i_mount, hdr);
 897		grown = 0;
 898	}
 899	/*
 900	 * Point to the biggest freespace in our data block.
 901	 */
 902	dup = (xfs_dir2_data_unused_t *)
 903	      ((char *)hdr + be16_to_cpu(bf[0].offset));
 904	needscan = needlog = 0;
 905	/*
 906	 * Mark the initial part of our freespace in use for the new entry.
 907	 */
 908	error = xfs_dir2_data_use_free(args, dbp, dup,
 909			(xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr),
 910			length, &needlog, &needscan);
 911	if (error) {
 912		xfs_trans_brelse(tp, lbp);
 913		return error;
 914	}
 915	/*
 916	 * Initialize our new entry (at last).
 917	 */
 918	dep = (xfs_dir2_data_entry_t *)dup;
 919	dep->inumber = cpu_to_be64(args->inumber);
 920	dep->namelen = args->namelen;
 921	memcpy(dep->name, args->name, dep->namelen);
 922	xfs_dir2_data_put_ftype(dp->i_mount, dep, args->filetype);
 923	tagp = xfs_dir2_data_entry_tag_p(dp->i_mount, dep);
 924	*tagp = cpu_to_be16((char *)dep - (char *)hdr);
 925	/*
 926	 * Need to scan fix up the bestfree table.
 927	 */
 928	if (needscan)
 929		xfs_dir2_data_freescan(dp->i_mount, hdr, &needlog);
 930	/*
 931	 * Need to log the data block's header.
 932	 */
 933	if (needlog)
 934		xfs_dir2_data_log_header(args, dbp);
 935	xfs_dir2_data_log_entry(args, dbp, dep);
 936	/*
 937	 * If the bests table needs to be changed, do it.
 938	 * Log the change unless we've already done that.
 939	 */
 940	if (be16_to_cpu(bestsp[use_block]) != be16_to_cpu(bf[0].length)) {
 941		bestsp[use_block] = bf[0].length;
 942		if (!grown)
 943			xfs_dir3_leaf_log_bests(args, lbp, use_block, use_block);
 944	}
 945
 946	lep = xfs_dir3_leaf_find_entry(&leafhdr, ents, index, compact, lowstale,
 947				       highstale, &lfloglow, &lfloghigh);
 948
 949	/*
 950	 * Fill in the new leaf entry.
 951	 */
 952	lep->hashval = cpu_to_be32(args->hashval);
 953	lep->address = cpu_to_be32(
 954				xfs_dir2_db_off_to_dataptr(args->geo, use_block,
 955				be16_to_cpu(*tagp)));
 956	/*
 957	 * Log the leaf fields and give up the buffers.
 958	 */
 959	xfs_dir2_leaf_hdr_to_disk(dp->i_mount, leaf, &leafhdr);
 960	xfs_dir3_leaf_log_header(args, lbp);
 961	xfs_dir3_leaf_log_ents(args, &leafhdr, lbp, lfloglow, lfloghigh);
 962	xfs_dir3_leaf_check(dp, lbp);
 963	xfs_dir3_data_check(dp, dbp);
 964	return 0;
 965}
 966
 967/*
 968 * Compact out any stale entries in the leaf.
 969 * Log the header and changed leaf entries, if any.
 970 */
 971void
 972xfs_dir3_leaf_compact(
 973	xfs_da_args_t	*args,		/* operation arguments */
 974	struct xfs_dir3_icleaf_hdr *leafhdr,
 975	struct xfs_buf	*bp)		/* leaf buffer */
 976{
 977	int		from;		/* source leaf index */
 978	xfs_dir2_leaf_t	*leaf;		/* leaf structure */
 979	int		loglow;		/* first leaf entry to log */
 980	int		to;		/* target leaf index */
 981	struct xfs_inode *dp = args->dp;
 982
 983	leaf = bp->b_addr;
 984	if (!leafhdr->stale)
 985		return;
 986
 987	/*
 988	 * Compress out the stale entries in place.
 989	 */
 990	for (from = to = 0, loglow = -1; from < leafhdr->count; from++) {
 991		if (leafhdr->ents[from].address ==
 992		    cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 993			continue;
 994		/*
 995		 * Only actually copy the entries that are different.
 996		 */
 997		if (from > to) {
 998			if (loglow == -1)
 999				loglow = to;
1000			leafhdr->ents[to] = leafhdr->ents[from];
1001		}
1002		to++;
1003	}
1004	/*
1005	 * Update and log the header, log the leaf entries.
1006	 */
1007	ASSERT(leafhdr->stale == from - to);
1008	leafhdr->count -= leafhdr->stale;
1009	leafhdr->stale = 0;
1010
1011	xfs_dir2_leaf_hdr_to_disk(dp->i_mount, leaf, leafhdr);
1012	xfs_dir3_leaf_log_header(args, bp);
1013	if (loglow != -1)
1014		xfs_dir3_leaf_log_ents(args, leafhdr, bp, loglow, to - 1);
1015}
1016
1017/*
1018 * Compact the leaf entries, removing stale ones.
1019 * Leave one stale entry behind - the one closest to our
1020 * insertion index - and the caller will shift that one to our insertion
1021 * point later.
1022 * Return new insertion index, where the remaining stale entry is,
1023 * and leaf logging indices.
1024 */
1025void
1026xfs_dir3_leaf_compact_x1(
1027	struct xfs_dir3_icleaf_hdr *leafhdr,
1028	struct xfs_dir2_leaf_entry *ents,
1029	int		*indexp,	/* insertion index */
1030	int		*lowstalep,	/* out: stale entry before us */
1031	int		*highstalep,	/* out: stale entry after us */
1032	int		*lowlogp,	/* out: low log index */
1033	int		*highlogp)	/* out: high log index */
1034{
1035	int		from;		/* source copy index */
1036	int		highstale;	/* stale entry at/after index */
1037	int		index;		/* insertion index */
1038	int		keepstale;	/* source index of kept stale */
1039	int		lowstale;	/* stale entry before index */
1040	int		newindex=0;	/* new insertion index */
1041	int		to;		/* destination copy index */
1042
1043	ASSERT(leafhdr->stale > 1);
1044	index = *indexp;
1045
1046	xfs_dir3_leaf_find_stale(leafhdr, ents, index, &lowstale, &highstale);
1047
1048	/*
1049	 * Pick the better of lowstale and highstale.
1050	 */
1051	if (lowstale >= 0 &&
1052	    (highstale == leafhdr->count ||
1053	     index - lowstale <= highstale - index))
1054		keepstale = lowstale;
1055	else
1056		keepstale = highstale;
1057	/*
1058	 * Copy the entries in place, removing all the stale entries
1059	 * except keepstale.
1060	 */
1061	for (from = to = 0; from < leafhdr->count; from++) {
1062		/*
1063		 * Notice the new value of index.
1064		 */
1065		if (index == from)
1066			newindex = to;
1067		if (from != keepstale &&
1068		    ents[from].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR)) {
1069			if (from == to)
1070				*lowlogp = to;
1071			continue;
1072		}
1073		/*
1074		 * Record the new keepstale value for the insertion.
1075		 */
1076		if (from == keepstale)
1077			lowstale = highstale = to;
1078		/*
1079		 * Copy only the entries that have moved.
1080		 */
1081		if (from > to)
1082			ents[to] = ents[from];
1083		to++;
1084	}
1085	ASSERT(from > to);
1086	/*
1087	 * If the insertion point was past the last entry,
1088	 * set the new insertion point accordingly.
1089	 */
1090	if (index == from)
1091		newindex = to;
1092	*indexp = newindex;
1093	/*
1094	 * Adjust the leaf header values.
1095	 */
1096	leafhdr->count -= from - to;
1097	leafhdr->stale = 1;
1098	/*
1099	 * Remember the low/high stale value only in the "right"
1100	 * direction.
1101	 */
1102	if (lowstale >= newindex)
1103		lowstale = -1;
1104	else
1105		highstale = leafhdr->count;
1106	*highlogp = leafhdr->count - 1;
1107	*lowstalep = lowstale;
1108	*highstalep = highstale;
1109}
1110
1111/*
1112 * Log the bests entries indicated from a leaf1 block.
1113 */
1114static void
1115xfs_dir3_leaf_log_bests(
1116	struct xfs_da_args	*args,
1117	struct xfs_buf		*bp,		/* leaf buffer */
1118	int			first,		/* first entry to log */
1119	int			last)		/* last entry to log */
1120{
1121	__be16			*firstb;	/* pointer to first entry */
1122	__be16			*lastb;		/* pointer to last entry */
1123	struct xfs_dir2_leaf	*leaf = bp->b_addr;
1124	xfs_dir2_leaf_tail_t	*ltp;		/* leaf tail structure */
1125
1126	ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1127	       leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC));
1128
1129	ltp = xfs_dir2_leaf_tail_p(args->geo, leaf);
1130	firstb = xfs_dir2_leaf_bests_p(ltp) + first;
1131	lastb = xfs_dir2_leaf_bests_p(ltp) + last;
1132	xfs_trans_log_buf(args->trans, bp,
1133		(uint)((char *)firstb - (char *)leaf),
1134		(uint)((char *)lastb - (char *)leaf + sizeof(*lastb) - 1));
1135}
1136
1137/*
1138 * Log the leaf entries indicated from a leaf1 or leafn block.
1139 */
1140void
1141xfs_dir3_leaf_log_ents(
1142	struct xfs_da_args	*args,
1143	struct xfs_dir3_icleaf_hdr *hdr,
1144	struct xfs_buf		*bp,
1145	int			first,
1146	int			last)
1147{
1148	xfs_dir2_leaf_entry_t	*firstlep;	/* pointer to first entry */
1149	xfs_dir2_leaf_entry_t	*lastlep;	/* pointer to last entry */
1150	struct xfs_dir2_leaf	*leaf = bp->b_addr;
1151
1152	ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1153	       leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
1154	       leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
1155	       leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC));
1156
1157	firstlep = &hdr->ents[first];
1158	lastlep = &hdr->ents[last];
1159	xfs_trans_log_buf(args->trans, bp,
1160		(uint)((char *)firstlep - (char *)leaf),
1161		(uint)((char *)lastlep - (char *)leaf + sizeof(*lastlep) - 1));
1162}
1163
1164/*
1165 * Log the header of the leaf1 or leafn block.
1166 */
1167void
1168xfs_dir3_leaf_log_header(
1169	struct xfs_da_args	*args,
1170	struct xfs_buf		*bp)
1171{
1172	struct xfs_dir2_leaf	*leaf = bp->b_addr;
1173
1174	ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1175	       leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
1176	       leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
1177	       leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC));
1178
1179	xfs_trans_log_buf(args->trans, bp,
1180			  (uint)((char *)&leaf->hdr - (char *)leaf),
1181			  args->geo->leaf_hdr_size - 1);
1182}
1183
1184/*
1185 * Log the tail of the leaf1 block.
1186 */
1187STATIC void
1188xfs_dir3_leaf_log_tail(
1189	struct xfs_da_args	*args,
1190	struct xfs_buf		*bp)
1191{
1192	struct xfs_dir2_leaf	*leaf = bp->b_addr;
1193	xfs_dir2_leaf_tail_t	*ltp;		/* leaf tail structure */
1194
1195	ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1196	       leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
1197	       leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
1198	       leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC));
1199
1200	ltp = xfs_dir2_leaf_tail_p(args->geo, leaf);
1201	xfs_trans_log_buf(args->trans, bp, (uint)((char *)ltp - (char *)leaf),
1202		(uint)(args->geo->blksize - 1));
1203}
1204
1205/*
1206 * Look up the entry referred to by args in the leaf format directory.
1207 * Most of the work is done by the xfs_dir2_leaf_lookup_int routine which
1208 * is also used by the node-format code.
1209 */
1210int
1211xfs_dir2_leaf_lookup(
1212	xfs_da_args_t		*args)		/* operation arguments */
1213{
1214	struct xfs_buf		*dbp;		/* data block buffer */
1215	xfs_dir2_data_entry_t	*dep;		/* data block entry */
1216	xfs_inode_t		*dp;		/* incore directory inode */
1217	int			error;		/* error return code */
1218	int			index;		/* found entry index */
1219	struct xfs_buf		*lbp;		/* leaf buffer */
1220	xfs_dir2_leaf_entry_t	*lep;		/* leaf entry */
1221	xfs_trans_t		*tp;		/* transaction pointer */
1222	struct xfs_dir3_icleaf_hdr leafhdr;
1223
1224	trace_xfs_dir2_leaf_lookup(args);
1225
1226	/*
1227	 * Look up name in the leaf block, returning both buffers and index.
1228	 */
1229	error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp, &leafhdr);
1230	if (error)
1231		return error;
1232
1233	tp = args->trans;
1234	dp = args->dp;
1235	xfs_dir3_leaf_check(dp, lbp);
1236
1237	/*
1238	 * Get to the leaf entry and contained data entry address.
1239	 */
1240	lep = &leafhdr.ents[index];
1241
1242	/*
1243	 * Point to the data entry.
1244	 */
1245	dep = (xfs_dir2_data_entry_t *)
1246	      ((char *)dbp->b_addr +
1247	       xfs_dir2_dataptr_to_off(args->geo, be32_to_cpu(lep->address)));
1248	/*
1249	 * Return the found inode number & CI name if appropriate
1250	 */
1251	args->inumber = be64_to_cpu(dep->inumber);
1252	args->filetype = xfs_dir2_data_get_ftype(dp->i_mount, dep);
1253	error = xfs_dir_cilookup_result(args, dep->name, dep->namelen);
1254	xfs_trans_brelse(tp, dbp);
1255	xfs_trans_brelse(tp, lbp);
1256	return error;
1257}
1258
1259/*
1260 * Look up name/hash in the leaf block.
1261 * Fill in indexp with the found index, and dbpp with the data buffer.
1262 * If not found dbpp will be NULL, and ENOENT comes back.
1263 * lbpp will always be filled in with the leaf buffer unless there's an error.
1264 */
1265static int					/* error */
1266xfs_dir2_leaf_lookup_int(
1267	xfs_da_args_t		*args,		/* operation arguments */
1268	struct xfs_buf		**lbpp,		/* out: leaf buffer */
1269	int			*indexp,	/* out: index in leaf block */
1270	struct xfs_buf		**dbpp,		/* out: data buffer */
1271	struct xfs_dir3_icleaf_hdr *leafhdr)
1272{
1273	xfs_dir2_db_t		curdb = -1;	/* current data block number */
1274	struct xfs_buf		*dbp = NULL;	/* data buffer */
1275	xfs_dir2_data_entry_t	*dep;		/* data entry */
1276	xfs_inode_t		*dp;		/* incore directory inode */
1277	int			error;		/* error return code */
1278	int			index;		/* index in leaf block */
1279	struct xfs_buf		*lbp;		/* leaf buffer */
1280	xfs_dir2_leaf_entry_t	*lep;		/* leaf entry */
1281	xfs_dir2_leaf_t		*leaf;		/* leaf structure */
1282	xfs_mount_t		*mp;		/* filesystem mount point */
1283	xfs_dir2_db_t		newdb;		/* new data block number */
1284	xfs_trans_t		*tp;		/* transaction pointer */
1285	xfs_dir2_db_t		cidb = -1;	/* case match data block no. */
1286	enum xfs_dacmp		cmp;		/* name compare result */
1287
1288	dp = args->dp;
1289	tp = args->trans;
1290	mp = dp->i_mount;
1291
1292	error = xfs_dir3_leaf_read(tp, dp, args->owner, args->geo->leafblk,
1293			&lbp);
1294	if (error)
1295		return error;
1296
1297	*lbpp = lbp;
1298	leaf = lbp->b_addr;
1299	xfs_dir3_leaf_check(dp, lbp);
1300	xfs_dir2_leaf_hdr_from_disk(mp, leafhdr, leaf);
1301
1302	/*
1303	 * Look for the first leaf entry with our hash value.
1304	 */
1305	index = xfs_dir2_leaf_search_hash(args, lbp);
1306	/*
1307	 * Loop over all the entries with the right hash value
1308	 * looking to match the name.
1309	 */
1310	for (lep = &leafhdr->ents[index];
1311	     index < leafhdr->count &&
1312			be32_to_cpu(lep->hashval) == args->hashval;
1313	     lep++, index++) {
1314		/*
1315		 * Skip over stale leaf entries.
1316		 */
1317		if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
1318			continue;
1319		/*
1320		 * Get the new data block number.
1321		 */
1322		newdb = xfs_dir2_dataptr_to_db(args->geo,
1323					       be32_to_cpu(lep->address));
1324		/*
1325		 * If it's not the same as the old data block number,
1326		 * need to pitch the old one and read the new one.
1327		 */
1328		if (newdb != curdb) {
1329			if (dbp)
1330				xfs_trans_brelse(tp, dbp);
1331			error = xfs_dir3_data_read(tp, dp, args->owner,
1332					xfs_dir2_db_to_da(args->geo, newdb), 0,
1333					&dbp);
1334			if (error) {
1335				xfs_trans_brelse(tp, lbp);
1336				return error;
1337			}
1338			curdb = newdb;
1339		}
1340		/*
1341		 * Point to the data entry.
1342		 */
1343		dep = (xfs_dir2_data_entry_t *)((char *)dbp->b_addr +
1344			xfs_dir2_dataptr_to_off(args->geo,
1345						be32_to_cpu(lep->address)));
1346		/*
1347		 * Compare name and if it's an exact match, return the index
1348		 * and buffer. If it's the first case-insensitive match, store
1349		 * the index and buffer and continue looking for an exact match.
1350		 */
1351		cmp = xfs_dir2_compname(args, dep->name, dep->namelen);
1352		if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) {
1353			args->cmpresult = cmp;
1354			*indexp = index;
1355			/* case exact match: return the current buffer. */
1356			if (cmp == XFS_CMP_EXACT) {
1357				*dbpp = dbp;
1358				return 0;
1359			}
1360			cidb = curdb;
1361		}
1362	}
1363	ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
1364	/*
1365	 * Here, we can only be doing a lookup (not a rename or remove).
1366	 * If a case-insensitive match was found earlier, re-read the
1367	 * appropriate data block if required and return it.
1368	 */
1369	if (args->cmpresult == XFS_CMP_CASE) {
1370		ASSERT(cidb != -1);
1371		if (cidb != curdb) {
1372			xfs_trans_brelse(tp, dbp);
1373			error = xfs_dir3_data_read(tp, dp, args->owner,
1374					xfs_dir2_db_to_da(args->geo, cidb), 0,
1375					&dbp);
1376			if (error) {
1377				xfs_trans_brelse(tp, lbp);
1378				return error;
1379			}
1380		}
1381		*dbpp = dbp;
1382		return 0;
1383	}
1384	/*
1385	 * No match found, return -ENOENT.
1386	 */
1387	ASSERT(cidb == -1);
1388	if (dbp)
1389		xfs_trans_brelse(tp, dbp);
1390	xfs_trans_brelse(tp, lbp);
1391	return -ENOENT;
1392}
1393
1394/*
1395 * Remove an entry from a leaf format directory.
1396 */
1397int						/* error */
1398xfs_dir2_leaf_removename(
1399	xfs_da_args_t		*args)		/* operation arguments */
1400{
1401	struct xfs_da_geometry	*geo = args->geo;
1402	__be16			*bestsp;	/* leaf block best freespace */
1403	xfs_dir2_data_hdr_t	*hdr;		/* data block header */
1404	xfs_dir2_db_t		db;		/* data block number */
1405	struct xfs_buf		*dbp;		/* data block buffer */
1406	xfs_dir2_data_entry_t	*dep;		/* data entry structure */
1407	xfs_inode_t		*dp;		/* incore directory inode */
1408	int			error;		/* error return code */
1409	xfs_dir2_db_t		i;		/* temporary data block # */
1410	int			index;		/* index into leaf entries */
1411	struct xfs_buf		*lbp;		/* leaf buffer */
1412	xfs_dir2_leaf_t		*leaf;		/* leaf structure */
1413	xfs_dir2_leaf_entry_t	*lep;		/* leaf entry */
1414	xfs_dir2_leaf_tail_t	*ltp;		/* leaf tail structure */
1415	int			needlog;	/* need to log data header */
1416	int			needscan;	/* need to rescan data frees */
1417	xfs_dir2_data_off_t	oldbest;	/* old value of best free */
1418	struct xfs_dir2_data_free *bf;		/* bestfree table */
1419	struct xfs_dir3_icleaf_hdr leafhdr;
1420
1421	trace_xfs_dir2_leaf_removename(args);
1422
1423	/*
1424	 * Lookup the leaf entry, get the leaf and data blocks read in.
1425	 */
1426	error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp, &leafhdr);
1427	if (error)
1428		return error;
1429
1430	dp = args->dp;
1431	leaf = lbp->b_addr;
1432	hdr = dbp->b_addr;
1433	xfs_dir3_data_check(dp, dbp);
1434	bf = xfs_dir2_data_bestfree_p(dp->i_mount, hdr);
1435
1436	/*
1437	 * Point to the leaf entry, use that to point to the data entry.
1438	 */
1439	lep = &leafhdr.ents[index];
1440	db = xfs_dir2_dataptr_to_db(geo, be32_to_cpu(lep->address));
1441	dep = (xfs_dir2_data_entry_t *)((char *)hdr +
1442		xfs_dir2_dataptr_to_off(geo, be32_to_cpu(lep->address)));
1443	needscan = needlog = 0;
1444	oldbest = be16_to_cpu(bf[0].length);
1445	ltp = xfs_dir2_leaf_tail_p(geo, leaf);
1446	bestsp = xfs_dir2_leaf_bests_p(ltp);
1447	if (be16_to_cpu(bestsp[db]) != oldbest) {
1448		xfs_buf_mark_corrupt(lbp);
1449		xfs_da_mark_sick(args);
1450		return -EFSCORRUPTED;
1451	}
1452
1453	/*
1454	 * Mark the former data entry unused.
1455	 */
1456	xfs_dir2_data_make_free(args, dbp,
1457		(xfs_dir2_data_aoff_t)((char *)dep - (char *)hdr),
1458		xfs_dir2_data_entsize(dp->i_mount, dep->namelen), &needlog,
1459		&needscan);
1460	/*
1461	 * We just mark the leaf entry stale by putting a null in it.
1462	 */
1463	leafhdr.stale++;
1464	xfs_dir2_leaf_hdr_to_disk(dp->i_mount, leaf, &leafhdr);
1465	xfs_dir3_leaf_log_header(args, lbp);
1466
1467	lep->address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
1468	xfs_dir3_leaf_log_ents(args, &leafhdr, lbp, index, index);
1469
1470	/*
1471	 * Scan the freespace in the data block again if necessary,
1472	 * log the data block header if necessary.
1473	 */
1474	if (needscan)
1475		xfs_dir2_data_freescan(dp->i_mount, hdr, &needlog);
1476	if (needlog)
1477		xfs_dir2_data_log_header(args, dbp);
1478	/*
1479	 * If the longest freespace in the data block has changed,
1480	 * put the new value in the bests table and log that.
1481	 */
1482	if (be16_to_cpu(bf[0].length) != oldbest) {
1483		bestsp[db] = bf[0].length;
1484		xfs_dir3_leaf_log_bests(args, lbp, db, db);
1485	}
1486	xfs_dir3_data_check(dp, dbp);
1487	/*
1488	 * If the data block is now empty then get rid of the data block.
1489	 */
1490	if (be16_to_cpu(bf[0].length) ==
1491	    geo->blksize - geo->data_entry_offset) {
1492		ASSERT(db != geo->datablk);
1493		if ((error = xfs_dir2_shrink_inode(args, db, dbp))) {
1494			/*
1495			 * Nope, can't get rid of it because it caused
1496			 * allocation of a bmap btree block to do so.
1497			 * Just go on, returning success, leaving the
1498			 * empty block in place.
1499			 */
1500			if (error == -ENOSPC && args->total == 0)
1501				error = 0;
1502			xfs_dir3_leaf_check(dp, lbp);
1503			return error;
1504		}
1505		dbp = NULL;
1506		/*
1507		 * If this is the last data block then compact the
1508		 * bests table by getting rid of entries.
1509		 */
1510		if (db == be32_to_cpu(ltp->bestcount) - 1) {
1511			/*
1512			 * Look for the last active entry (i).
1513			 */
1514			for (i = db - 1; i > 0; i--) {
1515				if (bestsp[i] != cpu_to_be16(NULLDATAOFF))
1516					break;
1517			}
1518			/*
1519			 * Copy the table down so inactive entries at the
1520			 * end are removed.
1521			 */
1522			memmove(&bestsp[db - i], bestsp,
1523				(be32_to_cpu(ltp->bestcount) - (db - i)) * sizeof(*bestsp));
1524			be32_add_cpu(&ltp->bestcount, -(db - i));
1525			xfs_dir3_leaf_log_tail(args, lbp);
1526			xfs_dir3_leaf_log_bests(args, lbp, 0,
1527						be32_to_cpu(ltp->bestcount) - 1);
1528		} else
1529			bestsp[db] = cpu_to_be16(NULLDATAOFF);
1530	}
1531	/*
1532	 * If the data block was not the first one, drop it.
1533	 */
1534	else if (db != geo->datablk)
1535		dbp = NULL;
1536
1537	xfs_dir3_leaf_check(dp, lbp);
1538	/*
1539	 * See if we can convert to block form.
1540	 */
1541	return xfs_dir2_leaf_to_block(args, lbp, dbp);
1542}
1543
1544/*
1545 * Replace the inode number in a leaf format directory entry.
1546 */
1547int						/* error */
1548xfs_dir2_leaf_replace(
1549	xfs_da_args_t		*args)		/* operation arguments */
1550{
1551	struct xfs_buf		*dbp;		/* data block buffer */
1552	xfs_dir2_data_entry_t	*dep;		/* data block entry */
1553	xfs_inode_t		*dp;		/* incore directory inode */
1554	int			error;		/* error return code */
1555	int			index;		/* index of leaf entry */
1556	struct xfs_buf		*lbp;		/* leaf buffer */
1557	xfs_dir2_leaf_entry_t	*lep;		/* leaf entry */
1558	xfs_trans_t		*tp;		/* transaction pointer */
1559	struct xfs_dir3_icleaf_hdr leafhdr;
1560
1561	trace_xfs_dir2_leaf_replace(args);
1562
1563	/*
1564	 * Look up the entry.
1565	 */
1566	error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp, &leafhdr);
1567	if (error)
1568		return error;
1569
1570	dp = args->dp;
1571	/*
1572	 * Point to the leaf entry, get data address from it.
1573	 */
1574	lep = &leafhdr.ents[index];
1575	/*
1576	 * Point to the data entry.
1577	 */
1578	dep = (xfs_dir2_data_entry_t *)
1579	      ((char *)dbp->b_addr +
1580	       xfs_dir2_dataptr_to_off(args->geo, be32_to_cpu(lep->address)));
1581	ASSERT(args->inumber != be64_to_cpu(dep->inumber));
1582	/*
1583	 * Put the new inode number in, log it.
1584	 */
1585	dep->inumber = cpu_to_be64(args->inumber);
1586	xfs_dir2_data_put_ftype(dp->i_mount, dep, args->filetype);
1587	tp = args->trans;
1588	xfs_dir2_data_log_entry(args, dbp, dep);
1589	xfs_dir3_leaf_check(dp, lbp);
1590	xfs_trans_brelse(tp, lbp);
1591	return 0;
1592}
1593
1594/*
1595 * Return index in the leaf block (lbp) which is either the first
1596 * one with this hash value, or if there are none, the insert point
1597 * for that hash value.
1598 */
1599int						/* index value */
1600xfs_dir2_leaf_search_hash(
1601	xfs_da_args_t		*args,		/* operation arguments */
1602	struct xfs_buf		*lbp)		/* leaf buffer */
1603{
1604	xfs_dahash_t		hash=0;		/* hash from this entry */
1605	xfs_dahash_t		hashwant;	/* hash value looking for */
1606	int			high;		/* high leaf index */
1607	int			low;		/* low leaf index */
1608	xfs_dir2_leaf_entry_t	*lep;		/* leaf entry */
1609	int			mid=0;		/* current leaf index */
1610	struct xfs_dir3_icleaf_hdr leafhdr;
1611
1612	xfs_dir2_leaf_hdr_from_disk(args->dp->i_mount, &leafhdr, lbp->b_addr);
1613
1614	/*
1615	 * Note, the table cannot be empty, so we have to go through the loop.
1616	 * Binary search the leaf entries looking for our hash value.
1617	 */
1618	for (lep = leafhdr.ents, low = 0, high = leafhdr.count - 1,
1619		hashwant = args->hashval;
1620	     low <= high; ) {
1621		mid = (low + high) >> 1;
1622		if ((hash = be32_to_cpu(lep[mid].hashval)) == hashwant)
1623			break;
1624		if (hash < hashwant)
1625			low = mid + 1;
1626		else
1627			high = mid - 1;
1628	}
1629	/*
1630	 * Found one, back up through all the equal hash values.
1631	 */
1632	if (hash == hashwant) {
1633		while (mid > 0 && be32_to_cpu(lep[mid - 1].hashval) == hashwant) {
1634			mid--;
1635		}
1636	}
1637	/*
1638	 * Need to point to an entry higher than ours.
1639	 */
1640	else if (hash < hashwant)
1641		mid++;
1642	return mid;
1643}
1644
1645/*
1646 * Trim off a trailing data block.  We know it's empty since the leaf
1647 * freespace table says so.
1648 */
1649int						/* error */
1650xfs_dir2_leaf_trim_data(
1651	xfs_da_args_t		*args,		/* operation arguments */
1652	struct xfs_buf		*lbp,		/* leaf buffer */
1653	xfs_dir2_db_t		db)		/* data block number */
1654{
1655	struct xfs_da_geometry	*geo = args->geo;
1656	__be16			*bestsp;	/* leaf bests table */
1657	struct xfs_buf		*dbp;		/* data block buffer */
1658	xfs_inode_t		*dp;		/* incore directory inode */
1659	int			error;		/* error return value */
1660	xfs_dir2_leaf_t		*leaf;		/* leaf structure */
1661	xfs_dir2_leaf_tail_t	*ltp;		/* leaf tail structure */
1662	xfs_trans_t		*tp;		/* transaction pointer */
1663
1664	dp = args->dp;
1665	tp = args->trans;
1666	/*
1667	 * Read the offending data block.  We need its buffer.
1668	 */
1669	error = xfs_dir3_data_read(tp, dp, args->owner,
1670			xfs_dir2_db_to_da(geo, db), 0, &dbp);
1671	if (error)
1672		return error;
1673
1674	leaf = lbp->b_addr;
1675	ltp = xfs_dir2_leaf_tail_p(geo, leaf);
1676
1677#ifdef DEBUG
1678{
1679	struct xfs_dir2_data_hdr *hdr = dbp->b_addr;
1680	struct xfs_dir2_data_free *bf =
1681		xfs_dir2_data_bestfree_p(dp->i_mount, hdr);
1682
1683	ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
1684	       hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC));
1685	ASSERT(be16_to_cpu(bf[0].length) ==
1686	       geo->blksize - geo->data_entry_offset);
1687	ASSERT(db == be32_to_cpu(ltp->bestcount) - 1);
1688}
1689#endif
1690
1691	/*
1692	 * Get rid of the data block.
1693	 */
1694	if ((error = xfs_dir2_shrink_inode(args, db, dbp))) {
1695		ASSERT(error != -ENOSPC);
1696		xfs_trans_brelse(tp, dbp);
1697		return error;
1698	}
1699	/*
1700	 * Eliminate the last bests entry from the table.
1701	 */
1702	bestsp = xfs_dir2_leaf_bests_p(ltp);
1703	be32_add_cpu(&ltp->bestcount, -1);
1704	memmove(&bestsp[1], &bestsp[0], be32_to_cpu(ltp->bestcount) * sizeof(*bestsp));
1705	xfs_dir3_leaf_log_tail(args, lbp);
1706	xfs_dir3_leaf_log_bests(args, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1707	return 0;
1708}
1709
1710static inline size_t
1711xfs_dir3_leaf_size(
1712	struct xfs_dir3_icleaf_hdr	*hdr,
1713	int				counts)
1714{
1715	int	entries;
1716	int	hdrsize;
1717
1718	entries = hdr->count - hdr->stale;
1719	if (hdr->magic == XFS_DIR2_LEAF1_MAGIC ||
1720	    hdr->magic == XFS_DIR2_LEAFN_MAGIC)
1721		hdrsize = sizeof(struct xfs_dir2_leaf_hdr);
1722	else
1723		hdrsize = sizeof(struct xfs_dir3_leaf_hdr);
1724
1725	return hdrsize + entries * sizeof(xfs_dir2_leaf_entry_t)
1726	               + counts * sizeof(xfs_dir2_data_off_t)
1727		       + sizeof(xfs_dir2_leaf_tail_t);
1728}
1729
1730/*
1731 * Convert node form directory to leaf form directory.
1732 * The root of the node form dir needs to already be a LEAFN block.
1733 * Just return if we can't do anything.
1734 */
1735int						/* error */
1736xfs_dir2_node_to_leaf(
1737	xfs_da_state_t		*state)		/* directory operation state */
1738{
1739	xfs_da_args_t		*args;		/* operation arguments */
1740	xfs_inode_t		*dp;		/* incore directory inode */
1741	int			error;		/* error return code */
1742	struct xfs_buf		*fbp;		/* buffer for freespace block */
1743	xfs_fileoff_t		fo;		/* freespace file offset */
1744	struct xfs_buf		*lbp;		/* buffer for leaf block */
1745	xfs_dir2_leaf_tail_t	*ltp;		/* tail of leaf structure */
1746	xfs_dir2_leaf_t		*leaf;		/* leaf structure */
1747	xfs_mount_t		*mp;		/* filesystem mount point */
1748	int			rval;		/* successful free trim? */
1749	xfs_trans_t		*tp;		/* transaction pointer */
1750	struct xfs_dir3_icleaf_hdr leafhdr;
1751	struct xfs_dir3_icfree_hdr freehdr;
1752
1753	/*
1754	 * There's more than a leaf level in the btree, so there must
1755	 * be multiple leafn blocks.  Give up.
1756	 */
1757	if (state->path.active > 1)
1758		return 0;
1759	args = state->args;
1760
1761	trace_xfs_dir2_node_to_leaf(args);
1762
1763	mp = state->mp;
1764	dp = args->dp;
1765	tp = args->trans;
1766	/*
1767	 * Get the last offset in the file.
1768	 */
1769	if ((error = xfs_bmap_last_offset(dp, &fo, XFS_DATA_FORK))) {
1770		return error;
1771	}
1772	fo -= args->geo->fsbcount;
1773	/*
1774	 * If there are freespace blocks other than the first one,
1775	 * take this opportunity to remove trailing empty freespace blocks
1776	 * that may have been left behind during no-space-reservation
1777	 * operations.
1778	 */
1779	while (fo > args->geo->freeblk) {
1780		if ((error = xfs_dir2_node_trim_free(args, fo, &rval))) {
1781			return error;
1782		}
1783		if (rval)
1784			fo -= args->geo->fsbcount;
1785		else
1786			return 0;
1787	}
1788	/*
1789	 * Now find the block just before the freespace block.
1790	 */
1791	if ((error = xfs_bmap_last_before(tp, dp, &fo, XFS_DATA_FORK))) {
1792		return error;
1793	}
1794	/*
1795	 * If it's not the single leaf block, give up.
1796	 */
1797	if (XFS_FSB_TO_B(mp, fo) > XFS_DIR2_LEAF_OFFSET + args->geo->blksize)
1798		return 0;
1799	lbp = state->path.blk[0].bp;
1800	leaf = lbp->b_addr;
1801	xfs_dir2_leaf_hdr_from_disk(mp, &leafhdr, leaf);
1802
1803	ASSERT(leafhdr.magic == XFS_DIR2_LEAFN_MAGIC ||
1804	       leafhdr.magic == XFS_DIR3_LEAFN_MAGIC);
1805
1806	/*
1807	 * Read the freespace block.
1808	 */
1809	error = xfs_dir2_free_read(tp, dp, args->owner, args->geo->freeblk,
1810			&fbp);
1811	if (error)
1812		return error;
1813	xfs_dir2_free_hdr_from_disk(mp, &freehdr, fbp->b_addr);
1814
1815	ASSERT(!freehdr.firstdb);
1816
1817	/*
1818	 * Now see if the leafn and free data will fit in a leaf1.
1819	 * If not, release the buffer and give up.
1820	 */
1821	if (xfs_dir3_leaf_size(&leafhdr, freehdr.nvalid) > args->geo->blksize) {
1822		xfs_trans_brelse(tp, fbp);
1823		return 0;
1824	}
1825
1826	/*
1827	 * If the leaf has any stale entries in it, compress them out.
1828	 */
1829	if (leafhdr.stale)
1830		xfs_dir3_leaf_compact(args, &leafhdr, lbp);
1831
1832	lbp->b_ops = &xfs_dir3_leaf1_buf_ops;
1833	xfs_trans_buf_set_type(tp, lbp, XFS_BLFT_DIR_LEAF1_BUF);
1834	leafhdr.magic = (leafhdr.magic == XFS_DIR2_LEAFN_MAGIC)
1835					? XFS_DIR2_LEAF1_MAGIC
1836					: XFS_DIR3_LEAF1_MAGIC;
1837
1838	/*
1839	 * Set up the leaf tail from the freespace block.
1840	 */
1841	ltp = xfs_dir2_leaf_tail_p(args->geo, leaf);
1842	ltp->bestcount = cpu_to_be32(freehdr.nvalid);
1843
1844	/*
1845	 * Set up the leaf bests table.
1846	 */
1847	memcpy(xfs_dir2_leaf_bests_p(ltp), freehdr.bests,
1848		freehdr.nvalid * sizeof(xfs_dir2_data_off_t));
1849
1850	xfs_dir2_leaf_hdr_to_disk(mp, leaf, &leafhdr);
1851	xfs_dir3_leaf_log_header(args, lbp);
1852	xfs_dir3_leaf_log_bests(args, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1853	xfs_dir3_leaf_log_tail(args, lbp);
1854	xfs_dir3_leaf_check(dp, lbp);
1855
1856	/*
1857	 * Get rid of the freespace block.
1858	 */
1859	error = xfs_dir2_shrink_inode(args,
1860			xfs_dir2_byte_to_db(args->geo, XFS_DIR2_FREE_OFFSET),
1861			fbp);
1862	if (error) {
1863		/*
1864		 * This can't fail here because it can only happen when
1865		 * punching out the middle of an extent, and this is an
1866		 * isolated block.
1867		 */
1868		ASSERT(error != -ENOSPC);
1869		return error;
1870	}
1871	fbp = NULL;
1872	/*
1873	 * Now see if we can convert the single-leaf directory
1874	 * down to a block form directory.
1875	 * This routine always kills the dabuf for the leaf, so
1876	 * eliminate it from the path.
1877	 */
1878	error = xfs_dir2_leaf_to_block(args, lbp, NULL);
1879	state->path.blk[0].bp = NULL;
1880	return error;
1881}