1/*
   2 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
   3 * All Rights Reserved.
   4 *
   5 * This program is free software; you can redistribute it and/or
   6 * modify it under the terms of the GNU General Public License as
   7 * published by the Free Software Foundation.
   8 *
   9 * This program is distributed in the hope that it would be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 *
  14 * You should have received a copy of the GNU General Public License
  15 * along with this program; if not, write the Free Software Foundation,
  16 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17 */
  18#include "xfs.h"
  19#include "xfs_fs.h"
  20#include "xfs_types.h"
  21#include "xfs_log.h"
  22#include "xfs_inum.h"
  23#include "xfs_trans.h"
  24#include "xfs_sb.h"
  25#include "xfs_ag.h"
  26#include "xfs_mount.h"
  27#include "xfs_da_btree.h"
  28#include "xfs_bmap_btree.h"
  29#include "xfs_dinode.h"
  30#include "xfs_inode.h"
  31#include "xfs_bmap.h"
  32#include "xfs_dir2_format.h"
  33#include "xfs_dir2_priv.h"
  34#include "xfs_error.h"
  35#include "xfs_trace.h"
  36
  37/*
  38 * Function declarations.
  39 */
  40static void xfs_dir2_free_log_header(xfs_trans_t *tp, xfs_dabuf_t *bp);
  41static int xfs_dir2_leafn_add(xfs_dabuf_t *bp, xfs_da_args_t *args, int index);
  42#ifdef DEBUG
  43static void xfs_dir2_leafn_check(xfs_inode_t *dp, xfs_dabuf_t *bp);
  44#else
  45#define	xfs_dir2_leafn_check(dp, bp)
  46#endif
  47static void xfs_dir2_leafn_moveents(xfs_da_args_t *args, xfs_dabuf_t *bp_s,
  48				    int start_s, xfs_dabuf_t *bp_d, int start_d,
  49				    int count);
  50static void xfs_dir2_leafn_rebalance(xfs_da_state_t *state,
  51				     xfs_da_state_blk_t *blk1,
  52				     xfs_da_state_blk_t *blk2);
  53static int xfs_dir2_leafn_remove(xfs_da_args_t *args, xfs_dabuf_t *bp,
  54				 int index, xfs_da_state_blk_t *dblk,
  55				 int *rval);
  56static int xfs_dir2_node_addname_int(xfs_da_args_t *args,
  57				     xfs_da_state_blk_t *fblk);
  58
  59/*
  60 * Log entries from a freespace block.
  61 */
  62STATIC void
  63xfs_dir2_free_log_bests(
  64	xfs_trans_t		*tp,		/* transaction pointer */
  65	xfs_dabuf_t		*bp,		/* freespace buffer */
  66	int			first,		/* first entry to log */
  67	int			last)		/* last entry to log */
  68{
  69	xfs_dir2_free_t		*free;		/* freespace structure */
  70
  71	free = bp->data;
  72	ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
  73	xfs_da_log_buf(tp, bp,
  74		(uint)((char *)&free->bests[first] - (char *)free),
  75		(uint)((char *)&free->bests[last] - (char *)free +
  76		       sizeof(free->bests[0]) - 1));
  77}
  78
  79/*
  80 * Log header from a freespace block.
  81 */
  82static void
  83xfs_dir2_free_log_header(
  84	xfs_trans_t		*tp,		/* transaction pointer */
  85	xfs_dabuf_t		*bp)		/* freespace buffer */
  86{
  87	xfs_dir2_free_t		*free;		/* freespace structure */
  88
  89	free = bp->data;
  90	ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
  91	xfs_da_log_buf(tp, bp, (uint)((char *)&free->hdr - (char *)free),
  92		(uint)(sizeof(xfs_dir2_free_hdr_t) - 1));
  93}
  94
  95/*
  96 * Convert a leaf-format directory to a node-format directory.
  97 * We need to change the magic number of the leaf block, and copy
  98 * the freespace table out of the leaf block into its own block.
  99 */
 100int						/* error */
 101xfs_dir2_leaf_to_node(
 102	xfs_da_args_t		*args,		/* operation arguments */
 103	xfs_dabuf_t		*lbp)		/* leaf buffer */
 104{
 105	xfs_inode_t		*dp;		/* incore directory inode */
 106	int			error;		/* error return value */
 107	xfs_dabuf_t		*fbp;		/* freespace buffer */
 108	xfs_dir2_db_t		fdb;		/* freespace block number */
 109	xfs_dir2_free_t		*free;		/* freespace structure */
 110	__be16			*from;		/* pointer to freespace entry */
 111	int			i;		/* leaf freespace index */
 112	xfs_dir2_leaf_t		*leaf;		/* leaf structure */
 113	xfs_dir2_leaf_tail_t	*ltp;		/* leaf tail structure */
 114	xfs_mount_t		*mp;		/* filesystem mount point */
 115	int			n;		/* count of live freespc ents */
 116	xfs_dir2_data_off_t	off;		/* freespace entry value */
 117	__be16			*to;		/* pointer to freespace entry */
 118	xfs_trans_t		*tp;		/* transaction pointer */
 119
 120	trace_xfs_dir2_leaf_to_node(args);
 121
 122	dp = args->dp;
 123	mp = dp->i_mount;
 124	tp = args->trans;
 125	/*
 126	 * Add a freespace block to the directory.
 127	 */
 128	if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_FREE_SPACE, &fdb))) {
 129		return error;
 130	}
 131	ASSERT(fdb == XFS_DIR2_FREE_FIRSTDB(mp));
 132	/*
 133	 * Get the buffer for the new freespace block.
 134	 */
 135	if ((error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(mp, fdb), -1, &fbp,
 136			XFS_DATA_FORK))) {
 137		return error;
 138	}
 139	ASSERT(fbp != NULL);
 140	free = fbp->data;
 141	leaf = lbp->data;
 142	ltp = xfs_dir2_leaf_tail_p(mp, leaf);
 143	/*
 144	 * Initialize the freespace block header.
 145	 */
 146	free->hdr.magic = cpu_to_be32(XFS_DIR2_FREE_MAGIC);
 147	free->hdr.firstdb = 0;
 148	ASSERT(be32_to_cpu(ltp->bestcount) <= (uint)dp->i_d.di_size / mp->m_dirblksize);
 149	free->hdr.nvalid = ltp->bestcount;
 150	/*
 151	 * Copy freespace entries from the leaf block to the new block.
 152	 * Count active entries.
 153	 */
 154	for (i = n = 0, from = xfs_dir2_leaf_bests_p(ltp), to = free->bests;
 155	     i < be32_to_cpu(ltp->bestcount); i++, from++, to++) {
 156		if ((off = be16_to_cpu(*from)) != NULLDATAOFF)
 157			n++;
 158		*to = cpu_to_be16(off);
 159	}
 160	free->hdr.nused = cpu_to_be32(n);
 161	leaf->hdr.info.magic = cpu_to_be16(XFS_DIR2_LEAFN_MAGIC);
 162	/*
 163	 * Log everything.
 164	 */
 165	xfs_dir2_leaf_log_header(tp, lbp);
 166	xfs_dir2_free_log_header(tp, fbp);
 167	xfs_dir2_free_log_bests(tp, fbp, 0, be32_to_cpu(free->hdr.nvalid) - 1);
 168	xfs_da_buf_done(fbp);
 169	xfs_dir2_leafn_check(dp, lbp);
 170	return 0;
 171}
 172
 173/*
 174 * Add a leaf entry to a leaf block in a node-form directory.
 175 * The other work necessary is done from the caller.
 176 */
 177static int					/* error */
 178xfs_dir2_leafn_add(
 179	xfs_dabuf_t		*bp,		/* leaf buffer */
 180	xfs_da_args_t		*args,		/* operation arguments */
 181	int			index)		/* insertion pt for new entry */
 182{
 183	int			compact;	/* compacting stale leaves */
 184	xfs_inode_t		*dp;		/* incore directory inode */
 185	int			highstale;	/* next stale entry */
 186	xfs_dir2_leaf_t		*leaf;		/* leaf structure */
 187	xfs_dir2_leaf_entry_t	*lep;		/* leaf entry */
 188	int			lfloghigh;	/* high leaf entry logging */
 189	int			lfloglow;	/* low leaf entry logging */
 190	int			lowstale;	/* previous stale entry */
 191	xfs_mount_t		*mp;		/* filesystem mount point */
 192	xfs_trans_t		*tp;		/* transaction pointer */
 193
 194	trace_xfs_dir2_leafn_add(args, index);
 195
 196	dp = args->dp;
 197	mp = dp->i_mount;
 198	tp = args->trans;
 199	leaf = bp->data;
 200
 201	/*
 202	 * Quick check just to make sure we are not going to index
 203	 * into other peoples memory
 204	 */
 205	if (index < 0)
 206		return XFS_ERROR(EFSCORRUPTED);
 207
 208	/*
 209	 * If there are already the maximum number of leaf entries in
 210	 * the block, if there are no stale entries it won't fit.
 211	 * Caller will do a split.  If there are stale entries we'll do
 212	 * a compact.
 213	 */
 214
 215	if (be16_to_cpu(leaf->hdr.count) == xfs_dir2_max_leaf_ents(mp)) {
 216		if (!leaf->hdr.stale)
 217			return XFS_ERROR(ENOSPC);
 218		compact = be16_to_cpu(leaf->hdr.stale) > 1;
 219	} else
 220		compact = 0;
 221	ASSERT(index == 0 || be32_to_cpu(leaf->ents[index - 1].hashval) <= args->hashval);
 222	ASSERT(index == be16_to_cpu(leaf->hdr.count) ||
 223	       be32_to_cpu(leaf->ents[index].hashval) >= args->hashval);
 224
 225	if (args->op_flags & XFS_DA_OP_JUSTCHECK)
 226		return 0;
 227
 228	/*
 229	 * Compact out all but one stale leaf entry.  Leaves behind
 230	 * the entry closest to index.
 231	 */
 232	if (compact) {
 233		xfs_dir2_leaf_compact_x1(bp, &index, &lowstale, &highstale,
 234			&lfloglow, &lfloghigh);
 235	}
 236	/*
 237	 * Set impossible logging indices for this case.
 238	 */
 239	else if (leaf->hdr.stale) {
 240		lfloglow = be16_to_cpu(leaf->hdr.count);
 241		lfloghigh = -1;
 242	}
 243
 244	/*
 245	 * Insert the new entry, log everything.
 246	 */
 247	lep = xfs_dir2_leaf_find_entry(leaf, index, compact, lowstale,
 248				       highstale, &lfloglow, &lfloghigh);
 249
 250	lep->hashval = cpu_to_be32(args->hashval);
 251	lep->address = cpu_to_be32(xfs_dir2_db_off_to_dataptr(mp,
 252				args->blkno, args->index));
 253	xfs_dir2_leaf_log_header(tp, bp);
 254	xfs_dir2_leaf_log_ents(tp, bp, lfloglow, lfloghigh);
 255	xfs_dir2_leafn_check(dp, bp);
 256	return 0;
 257}
 258
 259#ifdef DEBUG
 260/*
 261 * Check internal consistency of a leafn block.
 262 */
 263void
 264xfs_dir2_leafn_check(
 265	xfs_inode_t	*dp,			/* incore directory inode */
 266	xfs_dabuf_t	*bp)			/* leaf buffer */
 267{
 268	int		i;			/* leaf index */
 269	xfs_dir2_leaf_t	*leaf;			/* leaf structure */
 270	xfs_mount_t	*mp;			/* filesystem mount point */
 271	int		stale;			/* count of stale leaves */
 272
 273	leaf = bp->data;
 274	mp = dp->i_mount;
 275	ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
 276	ASSERT(be16_to_cpu(leaf->hdr.count) <= xfs_dir2_max_leaf_ents(mp));
 277	for (i = stale = 0; i < be16_to_cpu(leaf->hdr.count); i++) {
 278		if (i + 1 < be16_to_cpu(leaf->hdr.count)) {
 279			ASSERT(be32_to_cpu(leaf->ents[i].hashval) <=
 280			       be32_to_cpu(leaf->ents[i + 1].hashval));
 281		}
 282		if (leaf->ents[i].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 283			stale++;
 284	}
 285	ASSERT(be16_to_cpu(leaf->hdr.stale) == stale);
 286}
 287#endif	/* DEBUG */
 288
 289/*
 290 * Return the last hash value in the leaf.
 291 * Stale entries are ok.
 292 */
 293xfs_dahash_t					/* hash value */
 294xfs_dir2_leafn_lasthash(
 295	xfs_dabuf_t	*bp,			/* leaf buffer */
 296	int		*count)			/* count of entries in leaf */
 297{
 298	xfs_dir2_leaf_t	*leaf;			/* leaf structure */
 299
 300	leaf = bp->data;
 301	ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
 302	if (count)
 303		*count = be16_to_cpu(leaf->hdr.count);
 304	if (!leaf->hdr.count)
 305		return 0;
 306	return be32_to_cpu(leaf->ents[be16_to_cpu(leaf->hdr.count) - 1].hashval);
 307}
 308
 309/*
 310 * Look up a leaf entry for space to add a name in a node-format leaf block.
 311 * The extrablk in state is a freespace block.
 312 */
 313STATIC int
 314xfs_dir2_leafn_lookup_for_addname(
 315	xfs_dabuf_t		*bp,		/* leaf buffer */
 316	xfs_da_args_t		*args,		/* operation arguments */
 317	int			*indexp,	/* out: leaf entry index */
 318	xfs_da_state_t		*state)		/* state to fill in */
 319{
 320	xfs_dabuf_t		*curbp = NULL;	/* current data/free buffer */
 321	xfs_dir2_db_t		curdb = -1;	/* current data block number */
 322	xfs_dir2_db_t		curfdb = -1;	/* current free block number */
 323	xfs_inode_t		*dp;		/* incore directory inode */
 324	int			error;		/* error return value */
 325	int			fi;		/* free entry index */
 326	xfs_dir2_free_t		*free = NULL;	/* free block structure */
 327	int			index;		/* leaf entry index */
 328	xfs_dir2_leaf_t		*leaf;		/* leaf structure */
 329	int			length;		/* length of new data entry */
 330	xfs_dir2_leaf_entry_t	*lep;		/* leaf entry */
 331	xfs_mount_t		*mp;		/* filesystem mount point */
 332	xfs_dir2_db_t		newdb;		/* new data block number */
 333	xfs_dir2_db_t		newfdb;		/* new free block number */
 334	xfs_trans_t		*tp;		/* transaction pointer */
 335
 336	dp = args->dp;
 337	tp = args->trans;
 338	mp = dp->i_mount;
 339	leaf = bp->data;
 340	ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
 341#ifdef __KERNEL__
 342	ASSERT(be16_to_cpu(leaf->hdr.count) > 0);
 343#endif
 344	xfs_dir2_leafn_check(dp, bp);
 345	/*
 346	 * Look up the hash value in the leaf entries.
 347	 */
 348	index = xfs_dir2_leaf_search_hash(args, bp);
 349	/*
 350	 * Do we have a buffer coming in?
 351	 */
 352	if (state->extravalid) {
 353		/* If so, it's a free block buffer, get the block number. */
 354		curbp = state->extrablk.bp;
 355		curfdb = state->extrablk.blkno;
 356		free = curbp->data;
 357		ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
 358	}
 359	length = xfs_dir2_data_entsize(args->namelen);
 360	/*
 361	 * Loop over leaf entries with the right hash value.
 362	 */
 363	for (lep = &leaf->ents[index]; index < be16_to_cpu(leaf->hdr.count) &&
 364				be32_to_cpu(lep->hashval) == args->hashval;
 365				lep++, index++) {
 366		/*
 367		 * Skip stale leaf entries.
 368		 */
 369		if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
 370			continue;
 371		/*
 372		 * Pull the data block number from the entry.
 373		 */
 374		newdb = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
 375		/*
 376		 * For addname, we're looking for a place to put the new entry.
 377		 * We want to use a data block with an entry of equal
 378		 * hash value to ours if there is one with room.
 379		 *
 380		 * If this block isn't the data block we already have
 381		 * in hand, take a look at it.
 382		 */
 383		if (newdb != curdb) {
 384			curdb = newdb;
 385			/*
 386			 * Convert the data block to the free block
 387			 * holding its freespace information.
 388			 */
 389			newfdb = xfs_dir2_db_to_fdb(mp, newdb);
 390			/*
 391			 * If it's not the one we have in hand, read it in.
 392			 */
 393			if (newfdb != curfdb) {
 394				/*
 395				 * If we had one before, drop it.
 396				 */
 397				if (curbp)
 398					xfs_da_brelse(tp, curbp);
 399				/*
 400				 * Read the free block.
 401				 */
 402				error = xfs_da_read_buf(tp, dp,
 403						xfs_dir2_db_to_da(mp, newfdb),
 404						-1, &curbp, XFS_DATA_FORK);
 405				if (error)
 406					return error;
 407				free = curbp->data;
 408				ASSERT(be32_to_cpu(free->hdr.magic) ==
 409					XFS_DIR2_FREE_MAGIC);
 410				ASSERT((be32_to_cpu(free->hdr.firstdb) %
 411					xfs_dir2_free_max_bests(mp)) == 0);
 412				ASSERT(be32_to_cpu(free->hdr.firstdb) <= curdb);
 413				ASSERT(curdb < be32_to_cpu(free->hdr.firstdb) +
 414					be32_to_cpu(free->hdr.nvalid));
 415			}
 416			/*
 417			 * Get the index for our entry.
 418			 */
 419			fi = xfs_dir2_db_to_fdindex(mp, curdb);
 420			/*
 421			 * If it has room, return it.
 422			 */
 423			if (unlikely(free->bests[fi] ==
 424			    cpu_to_be16(NULLDATAOFF))) {
 425				XFS_ERROR_REPORT("xfs_dir2_leafn_lookup_int",
 426							XFS_ERRLEVEL_LOW, mp);
 427				if (curfdb != newfdb)
 428					xfs_da_brelse(tp, curbp);
 429				return XFS_ERROR(EFSCORRUPTED);
 430			}
 431			curfdb = newfdb;
 432			if (be16_to_cpu(free->bests[fi]) >= length)
 433				goto out;
 434		}
 435	}
 436	/* Didn't find any space */
 437	fi = -1;
 438out:
 439	ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
 440	if (curbp) {
 441		/* Giving back a free block. */
 442		state->extravalid = 1;
 443		state->extrablk.bp = curbp;
 444		state->extrablk.index = fi;
 445		state->extrablk.blkno = curfdb;
 446		state->extrablk.magic = XFS_DIR2_FREE_MAGIC;
 447	} else {
 448		state->extravalid = 0;
 449	}
 450	/*
 451	 * Return the index, that will be the insertion point.
 452	 */
 453	*indexp = index;
 454	return XFS_ERROR(ENOENT);
 455}
 456
 457/*
 458 * Look up a leaf entry in a node-format leaf block.
 459 * The extrablk in state a data block.
 460 */
 461STATIC int
 462xfs_dir2_leafn_lookup_for_entry(
 463	xfs_dabuf_t		*bp,		/* leaf buffer */
 464	xfs_da_args_t		*args,		/* operation arguments */
 465	int			*indexp,	/* out: leaf entry index */
 466	xfs_da_state_t		*state)		/* state to fill in */
 467{
 468	xfs_dabuf_t		*curbp = NULL;	/* current data/free buffer */
 469	xfs_dir2_db_t		curdb = -1;	/* current data block number */
 470	xfs_dir2_data_entry_t	*dep;		/* data block entry */
 471	xfs_inode_t		*dp;		/* incore directory inode */
 472	int			error;		/* error return value */
 473	int			index;		/* leaf entry index */
 474	xfs_dir2_leaf_t		*leaf;		/* leaf structure */
 475	xfs_dir2_leaf_entry_t	*lep;		/* leaf entry */
 476	xfs_mount_t		*mp;		/* filesystem mount point */
 477	xfs_dir2_db_t		newdb;		/* new data block number */
 478	xfs_trans_t		*tp;		/* transaction pointer */
 479	enum xfs_dacmp		cmp;		/* comparison result */
 480
 481	dp = args->dp;
 482	tp = args->trans;
 483	mp = dp->i_mount;
 484	leaf = bp->data;
 485	ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
 486#ifdef __KERNEL__
 487	ASSERT(be16_to_cpu(leaf->hdr.count) > 0);
 488#endif
 489	xfs_dir2_leafn_check(dp, bp);
 490	/*
 491	 * Look up the hash value in the leaf entries.
 492	 */
 493	index = xfs_dir2_leaf_search_hash(args, bp);
 494	/*
 495	 * Do we have a buffer coming in?
 496	 */
 497	if (state->extravalid) {
 498		curbp = state->extrablk.bp;
 499		curdb = state->extrablk.blkno;
 500	}
 501	/*
 502	 * Loop over leaf entries with the right hash value.
 503	 */
 504	for (lep = &leaf->ents[index]; index < be16_to_cpu(leaf->hdr.count) &&
 505				be32_to_cpu(lep->hashval) == args->hashval;
 506				lep++, index++) {
 507		/*
 508		 * Skip stale leaf entries.
 509		 */
 510		if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
 511			continue;
 512		/*
 513		 * Pull the data block number from the entry.
 514		 */
 515		newdb = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
 516		/*
 517		 * Not adding a new entry, so we really want to find
 518		 * the name given to us.
 519		 *
 520		 * If it's a different data block, go get it.
 521		 */
 522		if (newdb != curdb) {
 523			/*
 524			 * If we had a block before that we aren't saving
 525			 * for a CI name, drop it
 526			 */
 527			if (curbp && (args->cmpresult == XFS_CMP_DIFFERENT ||
 528						curdb != state->extrablk.blkno))
 529				xfs_da_brelse(tp, curbp);
 530			/*
 531			 * If needing the block that is saved with a CI match,
 532			 * use it otherwise read in the new data block.
 533			 */
 534			if (args->cmpresult != XFS_CMP_DIFFERENT &&
 535					newdb == state->extrablk.blkno) {
 536				ASSERT(state->extravalid);
 537				curbp = state->extrablk.bp;
 538			} else {
 539				error = xfs_da_read_buf(tp, dp,
 540						xfs_dir2_db_to_da(mp, newdb),
 541						-1, &curbp, XFS_DATA_FORK);
 542				if (error)
 543					return error;
 544			}
 545			xfs_dir2_data_check(dp, curbp);
 546			curdb = newdb;
 547		}
 548		/*
 549		 * Point to the data entry.
 550		 */
 551		dep = (xfs_dir2_data_entry_t *)((char *)curbp->data +
 552			xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address)));
 553		/*
 554		 * Compare the entry and if it's an exact match, return
 555		 * EEXIST immediately. If it's the first case-insensitive
 556		 * match, store the block & inode number and continue looking.
 557		 */
 558		cmp = mp->m_dirnameops->compname(args, dep->name, dep->namelen);
 559		if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) {
 560			/* If there is a CI match block, drop it */
 561			if (args->cmpresult != XFS_CMP_DIFFERENT &&
 562						curdb != state->extrablk.blkno)
 563				xfs_da_brelse(tp, state->extrablk.bp);
 564			args->cmpresult = cmp;
 565			args->inumber = be64_to_cpu(dep->inumber);
 566			*indexp = index;
 567			state->extravalid = 1;
 568			state->extrablk.bp = curbp;
 569			state->extrablk.blkno = curdb;
 570			state->extrablk.index = (int)((char *)dep -
 571							(char *)curbp->data);
 572			state->extrablk.magic = XFS_DIR2_DATA_MAGIC;
 573			if (cmp == XFS_CMP_EXACT)
 574				return XFS_ERROR(EEXIST);
 575		}
 576	}
 577	ASSERT(index == be16_to_cpu(leaf->hdr.count) ||
 578					(args->op_flags & XFS_DA_OP_OKNOENT));
 579	if (curbp) {
 580		if (args->cmpresult == XFS_CMP_DIFFERENT) {
 581			/* Giving back last used data block. */
 582			state->extravalid = 1;
 583			state->extrablk.bp = curbp;
 584			state->extrablk.index = -1;
 585			state->extrablk.blkno = curdb;
 586			state->extrablk.magic = XFS_DIR2_DATA_MAGIC;
 587		} else {
 588			/* If the curbp is not the CI match block, drop it */
 589			if (state->extrablk.bp != curbp)
 590				xfs_da_brelse(tp, curbp);
 591		}
 592	} else {
 593		state->extravalid = 0;
 594	}
 595	*indexp = index;
 596	return XFS_ERROR(ENOENT);
 597}
 598
 599/*
 600 * Look up a leaf entry in a node-format leaf block.
 601 * If this is an addname then the extrablk in state is a freespace block,
 602 * otherwise it's a data block.
 603 */
 604int
 605xfs_dir2_leafn_lookup_int(
 606	xfs_dabuf_t		*bp,		/* leaf buffer */
 607	xfs_da_args_t		*args,		/* operation arguments */
 608	int			*indexp,	/* out: leaf entry index */
 609	xfs_da_state_t		*state)		/* state to fill in */
 610{
 611	if (args->op_flags & XFS_DA_OP_ADDNAME)
 612		return xfs_dir2_leafn_lookup_for_addname(bp, args, indexp,
 613							state);
 614	return xfs_dir2_leafn_lookup_for_entry(bp, args, indexp, state);
 615}
 616
 617/*
 618 * Move count leaf entries from source to destination leaf.
 619 * Log entries and headers.  Stale entries are preserved.
 620 */
 621static void
 622xfs_dir2_leafn_moveents(
 623	xfs_da_args_t	*args,			/* operation arguments */
 624	xfs_dabuf_t	*bp_s,			/* source leaf buffer */
 625	int		start_s,		/* source leaf index */
 626	xfs_dabuf_t	*bp_d,			/* destination leaf buffer */
 627	int		start_d,		/* destination leaf index */
 628	int		count)			/* count of leaves to copy */
 629{
 630	xfs_dir2_leaf_t	*leaf_d;		/* destination leaf structure */
 631	xfs_dir2_leaf_t	*leaf_s;		/* source leaf structure */
 632	int		stale;			/* count stale leaves copied */
 633	xfs_trans_t	*tp;			/* transaction pointer */
 634
 635	trace_xfs_dir2_leafn_moveents(args, start_s, start_d, count);
 636
 637	/*
 638	 * Silently return if nothing to do.
 639	 */
 640	if (count == 0) {
 641		return;
 642	}
 643	tp = args->trans;
 644	leaf_s = bp_s->data;
 645	leaf_d = bp_d->data;
 646	/*
 647	 * If the destination index is not the end of the current
 648	 * destination leaf entries, open up a hole in the destination
 649	 * to hold the new entries.
 650	 */
 651	if (start_d < be16_to_cpu(leaf_d->hdr.count)) {
 652		memmove(&leaf_d->ents[start_d + count], &leaf_d->ents[start_d],
 653			(be16_to_cpu(leaf_d->hdr.count) - start_d) *
 654			sizeof(xfs_dir2_leaf_entry_t));
 655		xfs_dir2_leaf_log_ents(tp, bp_d, start_d + count,
 656			count + be16_to_cpu(leaf_d->hdr.count) - 1);
 657	}
 658	/*
 659	 * If the source has stale leaves, count the ones in the copy range
 660	 * so we can update the header correctly.
 661	 */
 662	if (leaf_s->hdr.stale) {
 663		int	i;			/* temp leaf index */
 664
 665		for (i = start_s, stale = 0; i < start_s + count; i++) {
 666			if (leaf_s->ents[i].address ==
 667			    cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 668				stale++;
 669		}
 670	} else
 671		stale = 0;
 672	/*
 673	 * Copy the leaf entries from source to destination.
 674	 */
 675	memcpy(&leaf_d->ents[start_d], &leaf_s->ents[start_s],
 676		count * sizeof(xfs_dir2_leaf_entry_t));
 677	xfs_dir2_leaf_log_ents(tp, bp_d, start_d, start_d + count - 1);
 678	/*
 679	 * If there are source entries after the ones we copied,
 680	 * delete the ones we copied by sliding the next ones down.
 681	 */
 682	if (start_s + count < be16_to_cpu(leaf_s->hdr.count)) {
 683		memmove(&leaf_s->ents[start_s], &leaf_s->ents[start_s + count],
 684			count * sizeof(xfs_dir2_leaf_entry_t));
 685		xfs_dir2_leaf_log_ents(tp, bp_s, start_s, start_s + count - 1);
 686	}
 687	/*
 688	 * Update the headers and log them.
 689	 */
 690	be16_add_cpu(&leaf_s->hdr.count, -(count));
 691	be16_add_cpu(&leaf_s->hdr.stale, -(stale));
 692	be16_add_cpu(&leaf_d->hdr.count, count);
 693	be16_add_cpu(&leaf_d->hdr.stale, stale);
 694	xfs_dir2_leaf_log_header(tp, bp_s);
 695	xfs_dir2_leaf_log_header(tp, bp_d);
 696	xfs_dir2_leafn_check(args->dp, bp_s);
 697	xfs_dir2_leafn_check(args->dp, bp_d);
 698}
 699
 700/*
 701 * Determine the sort order of two leaf blocks.
 702 * Returns 1 if both are valid and leaf2 should be before leaf1, else 0.
 703 */
 704int						/* sort order */
 705xfs_dir2_leafn_order(
 706	xfs_dabuf_t	*leaf1_bp,		/* leaf1 buffer */
 707	xfs_dabuf_t	*leaf2_bp)		/* leaf2 buffer */
 708{
 709	xfs_dir2_leaf_t	*leaf1;			/* leaf1 structure */
 710	xfs_dir2_leaf_t	*leaf2;			/* leaf2 structure */
 711
 712	leaf1 = leaf1_bp->data;
 713	leaf2 = leaf2_bp->data;
 714	ASSERT(leaf1->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
 715	ASSERT(leaf2->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
 716	if (be16_to_cpu(leaf1->hdr.count) > 0 &&
 717	    be16_to_cpu(leaf2->hdr.count) > 0 &&
 718	    (be32_to_cpu(leaf2->ents[0].hashval) < be32_to_cpu(leaf1->ents[0].hashval) ||
 719	     be32_to_cpu(leaf2->ents[be16_to_cpu(leaf2->hdr.count) - 1].hashval) <
 720	     be32_to_cpu(leaf1->ents[be16_to_cpu(leaf1->hdr.count) - 1].hashval)))
 721		return 1;
 722	return 0;
 723}
 724
 725/*
 726 * Rebalance leaf entries between two leaf blocks.
 727 * This is actually only called when the second block is new,
 728 * though the code deals with the general case.
 729 * A new entry will be inserted in one of the blocks, and that
 730 * entry is taken into account when balancing.
 731 */
 732static void
 733xfs_dir2_leafn_rebalance(
 734	xfs_da_state_t		*state,		/* btree cursor */
 735	xfs_da_state_blk_t	*blk1,		/* first btree block */
 736	xfs_da_state_blk_t	*blk2)		/* second btree block */
 737{
 738	xfs_da_args_t		*args;		/* operation arguments */
 739	int			count;		/* count (& direction) leaves */
 740	int			isleft;		/* new goes in left leaf */
 741	xfs_dir2_leaf_t		*leaf1;		/* first leaf structure */
 742	xfs_dir2_leaf_t		*leaf2;		/* second leaf structure */
 743	int			mid;		/* midpoint leaf index */
 744#ifdef DEBUG
 745	int			oldstale;	/* old count of stale leaves */
 746#endif
 747	int			oldsum;		/* old total leaf count */
 748	int			swap;		/* swapped leaf blocks */
 749
 750	args = state->args;
 751	/*
 752	 * If the block order is wrong, swap the arguments.
 753	 */
 754	if ((swap = xfs_dir2_leafn_order(blk1->bp, blk2->bp))) {
 755		xfs_da_state_blk_t	*tmp;	/* temp for block swap */
 756
 757		tmp = blk1;
 758		blk1 = blk2;
 759		blk2 = tmp;
 760	}
 761	leaf1 = blk1->bp->data;
 762	leaf2 = blk2->bp->data;
 763	oldsum = be16_to_cpu(leaf1->hdr.count) + be16_to_cpu(leaf2->hdr.count);
 764#ifdef DEBUG
 765	oldstale = be16_to_cpu(leaf1->hdr.stale) + be16_to_cpu(leaf2->hdr.stale);
 766#endif
 767	mid = oldsum >> 1;
 768	/*
 769	 * If the old leaf count was odd then the new one will be even,
 770	 * so we need to divide the new count evenly.
 771	 */
 772	if (oldsum & 1) {
 773		xfs_dahash_t	midhash;	/* middle entry hash value */
 774
 775		if (mid >= be16_to_cpu(leaf1->hdr.count))
 776			midhash = be32_to_cpu(leaf2->ents[mid - be16_to_cpu(leaf1->hdr.count)].hashval);
 777		else
 778			midhash = be32_to_cpu(leaf1->ents[mid].hashval);
 779		isleft = args->hashval <= midhash;
 780	}
 781	/*
 782	 * If the old count is even then the new count is odd, so there's
 783	 * no preferred side for the new entry.
 784	 * Pick the left one.
 785	 */
 786	else
 787		isleft = 1;
 788	/*
 789	 * Calculate moved entry count.  Positive means left-to-right,
 790	 * negative means right-to-left.  Then move the entries.
 791	 */
 792	count = be16_to_cpu(leaf1->hdr.count) - mid + (isleft == 0);
 793	if (count > 0)
 794		xfs_dir2_leafn_moveents(args, blk1->bp,
 795			be16_to_cpu(leaf1->hdr.count) - count, blk2->bp, 0, count);
 796	else if (count < 0)
 797		xfs_dir2_leafn_moveents(args, blk2->bp, 0, blk1->bp,
 798			be16_to_cpu(leaf1->hdr.count), count);
 799	ASSERT(be16_to_cpu(leaf1->hdr.count) + be16_to_cpu(leaf2->hdr.count) == oldsum);
 800	ASSERT(be16_to_cpu(leaf1->hdr.stale) + be16_to_cpu(leaf2->hdr.stale) == oldstale);
 801	/*
 802	 * Mark whether we're inserting into the old or new leaf.
 803	 */
 804	if (be16_to_cpu(leaf1->hdr.count) < be16_to_cpu(leaf2->hdr.count))
 805		state->inleaf = swap;
 806	else if (be16_to_cpu(leaf1->hdr.count) > be16_to_cpu(leaf2->hdr.count))
 807		state->inleaf = !swap;
 808	else
 809		state->inleaf =
 810			swap ^ (blk1->index <= be16_to_cpu(leaf1->hdr.count));
 811	/*
 812	 * Adjust the expected index for insertion.
 813	 */
 814	if (!state->inleaf)
 815		blk2->index = blk1->index - be16_to_cpu(leaf1->hdr.count);
 816
 817	/*
 818	 * Finally sanity check just to make sure we are not returning a
 819	 * negative index
 820	 */
 821	if(blk2->index < 0) {
 822		state->inleaf = 1;
 823		blk2->index = 0;
 824		xfs_alert(args->dp->i_mount,
 825	"%s: picked the wrong leaf? reverting original leaf: blk1->index %d\n",
 826			__func__, blk1->index);
 827	}
 828}
 829
 830/*
 831 * Remove an entry from a node directory.
 832 * This removes the leaf entry and the data entry,
 833 * and updates the free block if necessary.
 834 */
 835static int					/* error */
 836xfs_dir2_leafn_remove(
 837	xfs_da_args_t		*args,		/* operation arguments */
 838	xfs_dabuf_t		*bp,		/* leaf buffer */
 839	int			index,		/* leaf entry index */
 840	xfs_da_state_blk_t	*dblk,		/* data block */
 841	int			*rval)		/* resulting block needs join */
 842{
 843	xfs_dir2_data_hdr_t	*hdr;		/* data block header */
 844	xfs_dir2_db_t		db;		/* data block number */
 845	xfs_dabuf_t		*dbp;		/* data block buffer */
 846	xfs_dir2_data_entry_t	*dep;		/* data block entry */
 847	xfs_inode_t		*dp;		/* incore directory inode */
 848	xfs_dir2_leaf_t		*leaf;		/* leaf structure */
 849	xfs_dir2_leaf_entry_t	*lep;		/* leaf entry */
 850	int			longest;	/* longest data free entry */
 851	int			off;		/* data block entry offset */
 852	xfs_mount_t		*mp;		/* filesystem mount point */
 853	int			needlog;	/* need to log data header */
 854	int			needscan;	/* need to rescan data frees */
 855	xfs_trans_t		*tp;		/* transaction pointer */
 856
 857	trace_xfs_dir2_leafn_remove(args, index);
 858
 859	dp = args->dp;
 860	tp = args->trans;
 861	mp = dp->i_mount;
 862	leaf = bp->data;
 863	ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
 864	/*
 865	 * Point to the entry we're removing.
 866	 */
 867	lep = &leaf->ents[index];
 868	/*
 869	 * Extract the data block and offset from the entry.
 870	 */
 871	db = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
 872	ASSERT(dblk->blkno == db);
 873	off = xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address));
 874	ASSERT(dblk->index == off);
 875	/*
 876	 * Kill the leaf entry by marking it stale.
 877	 * Log the leaf block changes.
 878	 */
 879	be16_add_cpu(&leaf->hdr.stale, 1);
 880	xfs_dir2_leaf_log_header(tp, bp);
 881	lep->address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
 882	xfs_dir2_leaf_log_ents(tp, bp, index, index);
 883	/*
 884	 * Make the data entry free.  Keep track of the longest freespace
 885	 * in the data block in case it changes.
 886	 */
 887	dbp = dblk->bp;
 888	hdr = dbp->data;
 889	dep = (xfs_dir2_data_entry_t *)((char *)hdr + off);
 890	longest = be16_to_cpu(hdr->bestfree[0].length);
 891	needlog = needscan = 0;
 892	xfs_dir2_data_make_free(tp, dbp, off,
 893		xfs_dir2_data_entsize(dep->namelen), &needlog, &needscan);
 894	/*
 895	 * Rescan the data block freespaces for bestfree.
 896	 * Log the data block header if needed.
 897	 */
 898	if (needscan)
 899		xfs_dir2_data_freescan(mp, hdr, &needlog);
 900	if (needlog)
 901		xfs_dir2_data_log_header(tp, dbp);
 902	xfs_dir2_data_check(dp, dbp);
 903	/*
 904	 * If the longest data block freespace changes, need to update
 905	 * the corresponding freeblock entry.
 906	 */
 907	if (longest < be16_to_cpu(hdr->bestfree[0].length)) {
 908		int		error;		/* error return value */
 909		xfs_dabuf_t	*fbp;		/* freeblock buffer */
 910		xfs_dir2_db_t	fdb;		/* freeblock block number */
 911		int		findex;		/* index in freeblock entries */
 912		xfs_dir2_free_t	*free;		/* freeblock structure */
 913		int		logfree;	/* need to log free entry */
 914
 915		/*
 916		 * Convert the data block number to a free block,
 917		 * read in the free block.
 918		 */
 919		fdb = xfs_dir2_db_to_fdb(mp, db);
 920		if ((error = xfs_da_read_buf(tp, dp, xfs_dir2_db_to_da(mp, fdb),
 921				-1, &fbp, XFS_DATA_FORK))) {
 922			return error;
 923		}
 924		free = fbp->data;
 925		ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
 926		ASSERT(be32_to_cpu(free->hdr.firstdb) ==
 927		       xfs_dir2_free_max_bests(mp) *
 928		       (fdb - XFS_DIR2_FREE_FIRSTDB(mp)));
 929		/*
 930		 * Calculate which entry we need to fix.
 931		 */
 932		findex = xfs_dir2_db_to_fdindex(mp, db);
 933		longest = be16_to_cpu(hdr->bestfree[0].length);
 934		/*
 935		 * If the data block is now empty we can get rid of it
 936		 * (usually).
 937		 */
 938		if (longest == mp->m_dirblksize - (uint)sizeof(*hdr)) {
 939			/*
 940			 * Try to punch out the data block.
 941			 */
 942			error = xfs_dir2_shrink_inode(args, db, dbp);
 943			if (error == 0) {
 944				dblk->bp = NULL;
 945				hdr = NULL;
 946			}
 947			/*
 948			 * We can get ENOSPC if there's no space reservation.
 949			 * In this case just drop the buffer and some one else
 950			 * will eventually get rid of the empty block.
 951			 */
 952			else if (error == ENOSPC && args->total == 0)
 953				xfs_da_buf_done(dbp);
 954			else
 955				return error;
 956		}
 957		/*
 958		 * If we got rid of the data block, we can eliminate that entry
 959		 * in the free block.
 960		 */
 961		if (hdr == NULL) {
 962			/*
 963			 * One less used entry in the free table.
 964			 */
 965			be32_add_cpu(&free->hdr.nused, -1);
 966			xfs_dir2_free_log_header(tp, fbp);
 967			/*
 968			 * If this was the last entry in the table, we can
 969			 * trim the table size back.  There might be other
 970			 * entries at the end referring to non-existent
 971			 * data blocks, get those too.
 972			 */
 973			if (findex == be32_to_cpu(free->hdr.nvalid) - 1) {
 974				int	i;		/* free entry index */
 975
 976				for (i = findex - 1;
 977				     i >= 0 &&
 978				     free->bests[i] == cpu_to_be16(NULLDATAOFF);
 979				     i--)
 980					continue;
 981				free->hdr.nvalid = cpu_to_be32(i + 1);
 982				logfree = 0;
 983			}
 984			/*
 985			 * Not the last entry, just punch it out.
 986			 */
 987			else {
 988				free->bests[findex] = cpu_to_be16(NULLDATAOFF);
 989				logfree = 1;
 990			}
 991			/*
 992			 * If there are no useful entries left in the block,
 993			 * get rid of the block if we can.
 994			 */
 995			if (!free->hdr.nused) {
 996				error = xfs_dir2_shrink_inode(args, fdb, fbp);
 997				if (error == 0) {
 998					fbp = NULL;
 999					logfree = 0;
1000				} else if (error != ENOSPC || args->total != 0)
1001					return error;
1002				/*
1003				 * It's possible to get ENOSPC if there is no
1004				 * space reservation.  In this case some one
1005				 * else will eventually get rid of this block.
1006				 */
1007			}
1008		}
1009		/*
1010		 * Data block is not empty, just set the free entry to
1011		 * the new value.
1012		 */
1013		else {
1014			free->bests[findex] = cpu_to_be16(longest);
1015			logfree = 1;
1016		}
1017		/*
1018		 * Log the free entry that changed, unless we got rid of it.
1019		 */
1020		if (logfree)
1021			xfs_dir2_free_log_bests(tp, fbp, findex, findex);
1022		/*
1023		 * Drop the buffer if we still have it.
1024		 */
1025		if (fbp)
1026			xfs_da_buf_done(fbp);
1027	}
1028	xfs_dir2_leafn_check(dp, bp);
1029	/*
1030	 * Return indication of whether this leaf block is empty enough
1031	 * to justify trying to join it with a neighbor.
1032	 */
1033	*rval =
1034		((uint)sizeof(leaf->hdr) +
1035		 (uint)sizeof(leaf->ents[0]) *
1036		 (be16_to_cpu(leaf->hdr.count) - be16_to_cpu(leaf->hdr.stale))) <
1037		mp->m_dir_magicpct;
1038	return 0;
1039}
1040
1041/*
1042 * Split the leaf entries in the old block into old and new blocks.
1043 */
1044int						/* error */
1045xfs_dir2_leafn_split(
1046	xfs_da_state_t		*state,		/* btree cursor */
1047	xfs_da_state_blk_t	*oldblk,	/* original block */
1048	xfs_da_state_blk_t	*newblk)	/* newly created block */
1049{
1050	xfs_da_args_t		*args;		/* operation arguments */
1051	xfs_dablk_t		blkno;		/* new leaf block number */
1052	int			error;		/* error return value */
1053	xfs_mount_t		*mp;		/* filesystem mount point */
1054
1055	/*
1056	 * Allocate space for a new leaf node.
1057	 */
1058	args = state->args;
1059	mp = args->dp->i_mount;
1060	ASSERT(args != NULL);
1061	ASSERT(oldblk->magic == XFS_DIR2_LEAFN_MAGIC);
1062	error = xfs_da_grow_inode(args, &blkno);
1063	if (error) {
1064		return error;
1065	}
1066	/*
1067	 * Initialize the new leaf block.
1068	 */
1069	error = xfs_dir2_leaf_init(args, xfs_dir2_da_to_db(mp, blkno),
1070		&newblk->bp, XFS_DIR2_LEAFN_MAGIC);
1071	if (error) {
1072		return error;
1073	}
1074	newblk->blkno = blkno;
1075	newblk->magic = XFS_DIR2_LEAFN_MAGIC;
1076	/*
1077	 * Rebalance the entries across the two leaves, link the new
1078	 * block into the leaves.
1079	 */
1080	xfs_dir2_leafn_rebalance(state, oldblk, newblk);
1081	error = xfs_da_blk_link(state, oldblk, newblk);
1082	if (error) {
1083		return error;
1084	}
1085	/*
1086	 * Insert the new entry in the correct block.
1087	 */
1088	if (state->inleaf)
1089		error = xfs_dir2_leafn_add(oldblk->bp, args, oldblk->index);
1090	else
1091		error = xfs_dir2_leafn_add(newblk->bp, args, newblk->index);
1092	/*
1093	 * Update last hashval in each block since we added the name.
1094	 */
1095	oldblk->hashval = xfs_dir2_leafn_lasthash(oldblk->bp, NULL);
1096	newblk->hashval = xfs_dir2_leafn_lasthash(newblk->bp, NULL);
1097	xfs_dir2_leafn_check(args->dp, oldblk->bp);
1098	xfs_dir2_leafn_check(args->dp, newblk->bp);
1099	return error;
1100}
1101
1102/*
1103 * Check a leaf block and its neighbors to see if the block should be
1104 * collapsed into one or the other neighbor.  Always keep the block
1105 * with the smaller block number.
1106 * If the current block is over 50% full, don't try to join it, return 0.
1107 * If the block is empty, fill in the state structure and return 2.
1108 * If it can be collapsed, fill in the state structure and return 1.
1109 * If nothing can be done, return 0.
1110 */
1111int						/* error */
1112xfs_dir2_leafn_toosmall(
1113	xfs_da_state_t		*state,		/* btree cursor */
1114	int			*action)	/* resulting action to take */
1115{
1116	xfs_da_state_blk_t	*blk;		/* leaf block */
1117	xfs_dablk_t		blkno;		/* leaf block number */
1118	xfs_dabuf_t		*bp;		/* leaf buffer */
1119	int			bytes;		/* bytes in use */
1120	int			count;		/* leaf live entry count */
1121	int			error;		/* error return value */
1122	int			forward;	/* sibling block direction */
1123	int			i;		/* sibling counter */
1124	xfs_da_blkinfo_t	*info;		/* leaf block header */
1125	xfs_dir2_leaf_t		*leaf;		/* leaf structure */
1126	int			rval;		/* result from path_shift */
1127
1128	/*
1129	 * Check for the degenerate case of the block being over 50% full.
1130	 * If so, it's not worth even looking to see if we might be able
1131	 * to coalesce with a sibling.
1132	 */
1133	blk = &state->path.blk[state->path.active - 1];
1134	info = blk->bp->data;
1135	ASSERT(info->magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
1136	leaf = (xfs_dir2_leaf_t *)info;
1137	count = be16_to_cpu(leaf->hdr.count) - be16_to_cpu(leaf->hdr.stale);
1138	bytes = (uint)sizeof(leaf->hdr) + count * (uint)sizeof(leaf->ents[0]);
1139	if (bytes > (state->blocksize >> 1)) {
1140		/*
1141		 * Blk over 50%, don't try to join.
1142		 */
1143		*action = 0;
1144		return 0;
1145	}
1146	/*
1147	 * Check for the degenerate case of the block being empty.
1148	 * If the block is empty, we'll simply delete it, no need to
1149	 * coalesce it with a sibling block.  We choose (arbitrarily)
1150	 * to merge with the forward block unless it is NULL.
1151	 */
1152	if (count == 0) {
1153		/*
1154		 * Make altpath point to the block we want to keep and
1155		 * path point to the block we want to drop (this one).
1156		 */
1157		forward = (info->forw != 0);
1158		memcpy(&state->altpath, &state->path, sizeof(state->path));
1159		error = xfs_da_path_shift(state, &state->altpath, forward, 0,
1160			&rval);
1161		if (error)
1162			return error;
1163		*action = rval ? 2 : 0;
1164		return 0;
1165	}
1166	/*
1167	 * Examine each sibling block to see if we can coalesce with
1168	 * at least 25% free space to spare.  We need to figure out
1169	 * whether to merge with the forward or the backward block.
1170	 * We prefer coalescing with the lower numbered sibling so as
1171	 * to shrink a directory over time.
1172	 */
1173	forward = be32_to_cpu(info->forw) < be32_to_cpu(info->back);
1174	for (i = 0, bp = NULL; i < 2; forward = !forward, i++) {
1175		blkno = forward ? be32_to_cpu(info->forw) : be32_to_cpu(info->back);
1176		if (blkno == 0)
1177			continue;
1178		/*
1179		 * Read the sibling leaf block.
1180		 */
1181		if ((error =
1182		    xfs_da_read_buf(state->args->trans, state->args->dp, blkno,
1183			    -1, &bp, XFS_DATA_FORK))) {
1184			return error;
1185		}
1186		ASSERT(bp != NULL);
1187		/*
1188		 * Count bytes in the two blocks combined.
1189		 */
1190		leaf = (xfs_dir2_leaf_t *)info;
1191		count = be16_to_cpu(leaf->hdr.count) - be16_to_cpu(leaf->hdr.stale);
1192		bytes = state->blocksize - (state->blocksize >> 2);
1193		leaf = bp->data;
1194		ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
1195		count += be16_to_cpu(leaf->hdr.count) - be16_to_cpu(leaf->hdr.stale);
1196		bytes -= count * (uint)sizeof(leaf->ents[0]);
1197		/*
1198		 * Fits with at least 25% to spare.
1199		 */
1200		if (bytes >= 0)
1201			break;
1202		xfs_da_brelse(state->args->trans, bp);
1203	}
1204	/*
1205	 * Didn't like either block, give up.
1206	 */
1207	if (i >= 2) {
1208		*action = 0;
1209		return 0;
1210	}
1211	/*
1212	 * Done with the sibling leaf block here, drop the dabuf
1213	 * so path_shift can get it.
1214	 */
1215	xfs_da_buf_done(bp);
1216	/*
1217	 * Make altpath point to the block we want to keep (the lower
1218	 * numbered block) and path point to the block we want to drop.
1219	 */
1220	memcpy(&state->altpath, &state->path, sizeof(state->path));
1221	if (blkno < blk->blkno)
1222		error = xfs_da_path_shift(state, &state->altpath, forward, 0,
1223			&rval);
1224	else
1225		error = xfs_da_path_shift(state, &state->path, forward, 0,
1226			&rval);
1227	if (error) {
1228		return error;
1229	}
1230	*action = rval ? 0 : 1;
1231	return 0;
1232}
1233
1234/*
1235 * Move all the leaf entries from drop_blk to save_blk.
1236 * This is done as part of a join operation.
1237 */
1238void
1239xfs_dir2_leafn_unbalance(
1240	xfs_da_state_t		*state,		/* cursor */
1241	xfs_da_state_blk_t	*drop_blk,	/* dead block */
1242	xfs_da_state_blk_t	*save_blk)	/* surviving block */
1243{
1244	xfs_da_args_t		*args;		/* operation arguments */
1245	xfs_dir2_leaf_t		*drop_leaf;	/* dead leaf structure */
1246	xfs_dir2_leaf_t		*save_leaf;	/* surviving leaf structure */
1247
1248	args = state->args;
1249	ASSERT(drop_blk->magic == XFS_DIR2_LEAFN_MAGIC);
1250	ASSERT(save_blk->magic == XFS_DIR2_LEAFN_MAGIC);
1251	drop_leaf = drop_blk->bp->data;
1252	save_leaf = save_blk->bp->data;
1253	ASSERT(drop_leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
1254	ASSERT(save_leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
1255	/*
1256	 * If there are any stale leaf entries, take this opportunity
1257	 * to purge them.
1258	 */
1259	if (drop_leaf->hdr.stale)
1260		xfs_dir2_leaf_compact(args, drop_blk->bp);
1261	if (save_leaf->hdr.stale)
1262		xfs_dir2_leaf_compact(args, save_blk->bp);
1263	/*
1264	 * Move the entries from drop to the appropriate end of save.
1265	 */
1266	drop_blk->hashval = be32_to_cpu(drop_leaf->ents[be16_to_cpu(drop_leaf->hdr.count) - 1].hashval);
1267	if (xfs_dir2_leafn_order(save_blk->bp, drop_blk->bp))
1268		xfs_dir2_leafn_moveents(args, drop_blk->bp, 0, save_blk->bp, 0,
1269			be16_to_cpu(drop_leaf->hdr.count));
1270	else
1271		xfs_dir2_leafn_moveents(args, drop_blk->bp, 0, save_blk->bp,
1272			be16_to_cpu(save_leaf->hdr.count), be16_to_cpu(drop_leaf->hdr.count));
1273	save_blk->hashval = be32_to_cpu(save_leaf->ents[be16_to_cpu(save_leaf->hdr.count) - 1].hashval);
1274	xfs_dir2_leafn_check(args->dp, save_blk->bp);
1275}
1276
1277/*
1278 * Top-level node form directory addname routine.
1279 */
1280int						/* error */
1281xfs_dir2_node_addname(
1282	xfs_da_args_t		*args)		/* operation arguments */
1283{
1284	xfs_da_state_blk_t	*blk;		/* leaf block for insert */
1285	int			error;		/* error return value */
1286	int			rval;		/* sub-return value */
1287	xfs_da_state_t		*state;		/* btree cursor */
1288
1289	trace_xfs_dir2_node_addname(args);
1290
1291	/*
1292	 * Allocate and initialize the state (btree cursor).
1293	 */
1294	state = xfs_da_state_alloc();
1295	state->args = args;
1296	state->mp = args->dp->i_mount;
1297	state->blocksize = state->mp->m_dirblksize;
1298	state->node_ents = state->mp->m_dir_node_ents;
1299	/*
1300	 * Look up the name.  We're not supposed to find it, but
1301	 * this gives us the insertion point.
1302	 */
1303	error = xfs_da_node_lookup_int(state, &rval);
1304	if (error)
1305		rval = error;
1306	if (rval != ENOENT) {
1307		goto done;
1308	}
1309	/*
1310	 * Add the data entry to a data block.
1311	 * Extravalid is set to a freeblock found by lookup.
1312	 */
1313	rval = xfs_dir2_node_addname_int(args,
1314		state->extravalid ? &state->extrablk : NULL);
1315	if (rval) {
1316		goto done;
1317	}
1318	blk = &state->path.blk[state->path.active - 1];
1319	ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
1320	/*
1321	 * Add the new leaf entry.
1322	 */
1323	rval = xfs_dir2_leafn_add(blk->bp, args, blk->index);
1324	if (rval == 0) {
1325		/*
1326		 * It worked, fix the hash values up the btree.
1327		 */
1328		if (!(args->op_flags & XFS_DA_OP_JUSTCHECK))
1329			xfs_da_fixhashpath(state, &state->path);
1330	} else {
1331		/*
1332		 * It didn't work, we need to split the leaf block.
1333		 */
1334		if (args->total == 0) {
1335			ASSERT(rval == ENOSPC);
1336			goto done;
1337		}
1338		/*
1339		 * Split the leaf block and insert the new entry.
1340		 */
1341		rval = xfs_da_split(state);
1342	}
1343done:
1344	xfs_da_state_free(state);
1345	return rval;
1346}
1347
1348/*
1349 * Add the data entry for a node-format directory name addition.
1350 * The leaf entry is added in xfs_dir2_leafn_add.
1351 * We may enter with a freespace block that the lookup found.
1352 */
1353static int					/* error */
1354xfs_dir2_node_addname_int(
1355	xfs_da_args_t		*args,		/* operation arguments */
1356	xfs_da_state_blk_t	*fblk)		/* optional freespace block */
1357{
1358	xfs_dir2_data_hdr_t	*hdr;		/* data block header */
1359	xfs_dir2_db_t		dbno;		/* data block number */
1360	xfs_dabuf_t		*dbp;		/* data block buffer */
1361	xfs_dir2_data_entry_t	*dep;		/* data entry pointer */
1362	xfs_inode_t		*dp;		/* incore directory inode */
1363	xfs_dir2_data_unused_t	*dup;		/* data unused entry pointer */
1364	int			error;		/* error return value */
1365	xfs_dir2_db_t		fbno;		/* freespace block number */
1366	xfs_dabuf_t		*fbp;		/* freespace buffer */
1367	int			findex;		/* freespace entry index */
1368	xfs_dir2_free_t		*free=NULL;	/* freespace block structure */
1369	xfs_dir2_db_t		ifbno;		/* initial freespace block no */
1370	xfs_dir2_db_t		lastfbno=0;	/* highest freespace block no */
1371	int			length;		/* length of the new entry */
1372	int			logfree;	/* need to log free entry */
1373	xfs_mount_t		*mp;		/* filesystem mount point */
1374	int			needlog;	/* need to log data header */
1375	int			needscan;	/* need to rescan data frees */
1376	__be16			*tagp;		/* data entry tag pointer */
1377	xfs_trans_t		*tp;		/* transaction pointer */
1378
1379	dp = args->dp;
1380	mp = dp->i_mount;
1381	tp = args->trans;
1382	length = xfs_dir2_data_entsize(args->namelen);
1383	/*
1384	 * If we came in with a freespace block that means that lookup
1385	 * found an entry with our hash value.  This is the freespace
1386	 * block for that data entry.
1387	 */
1388	if (fblk) {
1389		fbp = fblk->bp;
1390		/*
1391		 * Remember initial freespace block number.
1392		 */
1393		ifbno = fblk->blkno;
1394		free = fbp->data;
1395		ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
1396		findex = fblk->index;
1397		/*
1398		 * This means the free entry showed that the data block had
1399		 * space for our entry, so we remembered it.
1400		 * Use that data block.
1401		 */
1402		if (findex >= 0) {
1403			ASSERT(findex < be32_to_cpu(free->hdr.nvalid));
1404			ASSERT(be16_to_cpu(free->bests[findex]) != NULLDATAOFF);
1405			ASSERT(be16_to_cpu(free->bests[findex]) >= length);
1406			dbno = be32_to_cpu(free->hdr.firstdb) + findex;
1407		}
1408		/*
1409		 * The data block looked at didn't have enough room.
1410		 * We'll start at the beginning of the freespace entries.
1411		 */
1412		else {
1413			dbno = -1;
1414			findex = 0;
1415		}
1416	}
1417	/*
1418	 * Didn't come in with a freespace block, so don't have a data block.
1419	 */
1420	else {
1421		ifbno = dbno = -1;
1422		fbp = NULL;
1423		findex = 0;
1424	}
1425	/*
1426	 * If we don't have a data block yet, we're going to scan the
1427	 * freespace blocks looking for one.  Figure out what the
1428	 * highest freespace block number is.
1429	 */
1430	if (dbno == -1) {
1431		xfs_fileoff_t	fo;		/* freespace block number */
1432
1433		if ((error = xfs_bmap_last_offset(tp, dp, &fo, XFS_DATA_FORK)))
1434			return error;
1435		lastfbno = xfs_dir2_da_to_db(mp, (xfs_dablk_t)fo);
1436		fbno = ifbno;
1437	}
1438	/*
1439	 * While we haven't identified a data block, search the freeblock
1440	 * data for a good data block.  If we find a null freeblock entry,
1441	 * indicating a hole in the data blocks, remember that.
1442	 */
1443	while (dbno == -1) {
1444		/*
1445		 * If we don't have a freeblock in hand, get the next one.
1446		 */
1447		if (fbp == NULL) {
1448			/*
1449			 * Happens the first time through unless lookup gave
1450			 * us a freespace block to start with.
1451			 */
1452			if (++fbno == 0)
1453				fbno = XFS_DIR2_FREE_FIRSTDB(mp);
1454			/*
1455			 * If it's ifbno we already looked at it.
1456			 */
1457			if (fbno == ifbno)
1458				fbno++;
1459			/*
1460			 * If it's off the end we're done.
1461			 */
1462			if (fbno >= lastfbno)
1463				break;
1464			/*
1465			 * Read the block.  There can be holes in the
1466			 * freespace blocks, so this might not succeed.
1467			 * This should be really rare, so there's no reason
1468			 * to avoid it.
1469			 */
1470			if ((error = xfs_da_read_buf(tp, dp,
1471					xfs_dir2_db_to_da(mp, fbno), -2, &fbp,
1472					XFS_DATA_FORK))) {
1473				return error;
1474			}
1475			if (unlikely(fbp == NULL)) {
1476				continue;
1477			}
1478			free = fbp->data;
1479			ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
1480			findex = 0;
1481		}
1482		/*
1483		 * Look at the current free entry.  Is it good enough?
1484		 */
1485		if (be16_to_cpu(free->bests[findex]) != NULLDATAOFF &&
1486		    be16_to_cpu(free->bests[findex]) >= length)
1487			dbno = be32_to_cpu(free->hdr.firstdb) + findex;
1488		else {
1489			/*
1490			 * Are we done with the freeblock?
1491			 */
1492			if (++findex == be32_to_cpu(free->hdr.nvalid)) {
1493				/*
1494				 * Drop the block.
1495				 */
1496				xfs_da_brelse(tp, fbp);
1497				fbp = NULL;
1498				if (fblk && fblk->bp)
1499					fblk->bp = NULL;
1500			}
1501		}
1502	}
1503	/*
1504	 * If we don't have a data block, we need to allocate one and make
1505	 * the freespace entries refer to it.
1506	 */
1507	if (unlikely(dbno == -1)) {
1508		/*
1509		 * Not allowed to allocate, return failure.
1510		 */
1511		if ((args->op_flags & XFS_DA_OP_JUSTCHECK) ||
1512							args->total == 0) {
1513			/*
1514			 * Drop the freespace buffer unless it came from our
1515			 * caller.
1516			 */
1517			if ((fblk == NULL || fblk->bp == NULL) && fbp != NULL)
1518				xfs_da_buf_done(fbp);
1519			return XFS_ERROR(ENOSPC);
1520		}
1521		/*
1522		 * Allocate and initialize the new data block.
1523		 */
1524		if (unlikely((error = xfs_dir2_grow_inode(args,
1525							 XFS_DIR2_DATA_SPACE,
1526							 &dbno)) ||
1527		    (error = xfs_dir2_data_init(args, dbno, &dbp)))) {
1528			/*
1529			 * Drop the freespace buffer unless it came from our
1530			 * caller.
1531			 */
1532			if ((fblk == NULL || fblk->bp == NULL) && fbp != NULL)
1533				xfs_da_buf_done(fbp);
1534			return error;
1535		}
1536		/*
1537		 * If (somehow) we have a freespace block, get rid of it.
1538		 */
1539		if (fbp)
1540			xfs_da_brelse(tp, fbp);
1541		if (fblk && fblk->bp)
1542			fblk->bp = NULL;
1543
1544		/*
1545		 * Get the freespace block corresponding to the data block
1546		 * that was just allocated.
1547		 */
1548		fbno = xfs_dir2_db_to_fdb(mp, dbno);
1549		if (unlikely(error = xfs_da_read_buf(tp, dp,
1550				xfs_dir2_db_to_da(mp, fbno), -2, &fbp,
1551				XFS_DATA_FORK))) {
1552			xfs_da_buf_done(dbp);
1553			return error;
1554  		}
1555		/*
1556		 * If there wasn't a freespace block, the read will
1557		 * return a NULL fbp.  Allocate and initialize a new one.
1558		 */
1559		if( fbp == NULL ) {
1560			if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_FREE_SPACE,
1561							&fbno))) {
1562				return error;
1563			}
1564
1565			if (unlikely(xfs_dir2_db_to_fdb(mp, dbno) != fbno)) {
1566				xfs_alert(mp,
1567			"%s: dir ino %llu needed freesp block %lld for\n"
1568			"  data block %lld, got %lld ifbno %llu lastfbno %d",
1569					__func__, (unsigned long long)dp->i_ino,
1570					(long long)xfs_dir2_db_to_fdb(mp, dbno),
1571					(long long)dbno, (long long)fbno,
1572					(unsigned long long)ifbno, lastfbno);
1573				if (fblk) {
1574					xfs_alert(mp,
1575				" fblk 0x%p blkno %llu index %d magic 0x%x",
1576						fblk,
1577						(unsigned long long)fblk->blkno,
1578						fblk->index,
1579						fblk->magic);
1580				} else {
1581					xfs_alert(mp, " ... fblk is NULL");
1582				}
1583				XFS_ERROR_REPORT("xfs_dir2_node_addname_int",
1584						 XFS_ERRLEVEL_LOW, mp);
1585				return XFS_ERROR(EFSCORRUPTED);
1586			}
1587
1588			/*
1589			 * Get a buffer for the new block.
1590			 */
1591			if ((error = xfs_da_get_buf(tp, dp,
1592						   xfs_dir2_db_to_da(mp, fbno),
1593						   -1, &fbp, XFS_DATA_FORK))) {
1594				return error;
1595			}
1596			ASSERT(fbp != NULL);
1597
1598			/*
1599			 * Initialize the new block to be empty, and remember
1600			 * its first slot as our empty slot.
1601			 */
1602			free = fbp->data;
1603			free->hdr.magic = cpu_to_be32(XFS_DIR2_FREE_MAGIC);
1604			free->hdr.firstdb = cpu_to_be32(
1605				(fbno - XFS_DIR2_FREE_FIRSTDB(mp)) *
1606				xfs_dir2_free_max_bests(mp));
1607			free->hdr.nvalid = 0;
1608			free->hdr.nused = 0;
1609		} else {
1610			free = fbp->data;
1611			ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
1612		}
1613
1614		/*
1615		 * Set the freespace block index from the data block number.
1616		 */
1617		findex = xfs_dir2_db_to_fdindex(mp, dbno);
1618		/*
1619		 * If it's after the end of the current entries in the
1620		 * freespace block, extend that table.
1621		 */
1622		if (findex >= be32_to_cpu(free->hdr.nvalid)) {
1623			ASSERT(findex < xfs_dir2_free_max_bests(mp));
1624			free->hdr.nvalid = cpu_to_be32(findex + 1);
1625			/*
1626			 * Tag new entry so nused will go up.
1627			 */
1628			free->bests[findex] = cpu_to_be16(NULLDATAOFF);
1629		}
1630		/*
1631		 * If this entry was for an empty data block
1632		 * (this should always be true) then update the header.
1633		 */
1634		if (free->bests[findex] == cpu_to_be16(NULLDATAOFF)) {
1635			be32_add_cpu(&free->hdr.nused, 1);
1636			xfs_dir2_free_log_header(tp, fbp);
1637		}
1638		/*
1639		 * Update the real value in the table.
1640		 * We haven't allocated the data entry yet so this will
1641		 * change again.
1642		 */
1643		hdr = dbp->data;
1644		free->bests[findex] = hdr->bestfree[0].length;
1645		logfree = 1;
1646	}
1647	/*
1648	 * We had a data block so we don't have to make a new one.
1649	 */
1650	else {
1651		/*
1652		 * If just checking, we succeeded.
1653		 */
1654		if (args->op_flags & XFS_DA_OP_JUSTCHECK) {
1655			if ((fblk == NULL || fblk->bp == NULL) && fbp != NULL)
1656				xfs_da_buf_done(fbp);
1657			return 0;
1658		}
1659		/*
1660		 * Read the data block in.
1661		 */
1662		if (unlikely(
1663		    error = xfs_da_read_buf(tp, dp, xfs_dir2_db_to_da(mp, dbno),
1664				-1, &dbp, XFS_DATA_FORK))) {
1665			if ((fblk == NULL || fblk->bp == NULL) && fbp != NULL)
1666				xfs_da_buf_done(fbp);
1667			return error;
1668		}
1669		hdr = dbp->data;
1670		logfree = 0;
1671	}
1672	ASSERT(be16_to_cpu(hdr->bestfree[0].length) >= length);
1673	/*
1674	 * Point to the existing unused space.
1675	 */
1676	dup = (xfs_dir2_data_unused_t *)
1677	      ((char *)hdr + be16_to_cpu(hdr->bestfree[0].offset));
1678	needscan = needlog = 0;
1679	/*
1680	 * Mark the first part of the unused space, inuse for us.
1681	 */
1682	xfs_dir2_data_use_free(tp, dbp, dup,
1683		(xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr), length,
1684		&needlog, &needscan);
1685	/*
1686	 * Fill in the new entry and log it.
1687	 */
1688	dep = (xfs_dir2_data_entry_t *)dup;
1689	dep->inumber = cpu_to_be64(args->inumber);
1690	dep->namelen = args->namelen;
1691	memcpy(dep->name, args->name, dep->namelen);
1692	tagp = xfs_dir2_data_entry_tag_p(dep);
1693	*tagp = cpu_to_be16((char *)dep - (char *)hdr);
1694	xfs_dir2_data_log_entry(tp, dbp, dep);
1695	/*
1696	 * Rescan the block for bestfree if needed.
1697	 */
1698	if (needscan)
1699		xfs_dir2_data_freescan(mp, hdr, &needlog);
1700	/*
1701	 * Log the data block header if needed.
1702	 */
1703	if (needlog)
1704		xfs_dir2_data_log_header(tp, dbp);
1705	/*
1706	 * If the freespace entry is now wrong, update it.
1707	 */
1708	if (be16_to_cpu(free->bests[findex]) != be16_to_cpu(hdr->bestfree[0].length)) {
1709		free->bests[findex] = hdr->bestfree[0].length;
1710		logfree = 1;
1711	}
1712	/*
1713	 * Log the freespace entry if needed.
1714	 */
1715	if (logfree)
1716		xfs_dir2_free_log_bests(tp, fbp, findex, findex);
1717	/*
1718	 * If the caller didn't hand us the freespace block, drop it.
1719	 */
1720	if ((fblk == NULL || fblk->bp == NULL) && fbp != NULL)
1721		xfs_da_buf_done(fbp);
1722	/*
1723	 * Return the data block and offset in args, then drop the data block.
1724	 */
1725	args->blkno = (xfs_dablk_t)dbno;
1726	args->index = be16_to_cpu(*tagp);
1727	xfs_da_buf_done(dbp);
1728	return 0;
1729}
1730
1731/*
1732 * Lookup an entry in a node-format directory.
1733 * All the real work happens in xfs_da_node_lookup_int.
1734 * The only real output is the inode number of the entry.
1735 */
1736int						/* error */
1737xfs_dir2_node_lookup(
1738	xfs_da_args_t	*args)			/* operation arguments */
1739{
1740	int		error;			/* error return value */
1741	int		i;			/* btree level */
1742	int		rval;			/* operation return value */
1743	xfs_da_state_t	*state;			/* btree cursor */
1744
1745	trace_xfs_dir2_node_lookup(args);
1746
1747	/*
1748	 * Allocate and initialize the btree cursor.
1749	 */
1750	state = xfs_da_state_alloc();
1751	state->args = args;
1752	state->mp = args->dp->i_mount;
1753	state->blocksize = state->mp->m_dirblksize;
1754	state->node_ents = state->mp->m_dir_node_ents;
1755	/*
1756	 * Fill in the path to the entry in the cursor.
1757	 */
1758	error = xfs_da_node_lookup_int(state, &rval);
1759	if (error)
1760		rval = error;
1761	else if (rval == ENOENT && args->cmpresult == XFS_CMP_CASE) {
1762		/* If a CI match, dup the actual name and return EEXIST */
1763		xfs_dir2_data_entry_t	*dep;
1764
1765		dep = (xfs_dir2_data_entry_t *)((char *)state->extrablk.bp->
1766						data + state->extrablk.index);
1767		rval = xfs_dir_cilookup_result(args, dep->name, dep->namelen);
1768	}
1769	/*
1770	 * Release the btree blocks and leaf block.
1771	 */
1772	for (i = 0; i < state->path.active; i++) {
1773		xfs_da_brelse(args->trans, state->path.blk[i].bp);
1774		state->path.blk[i].bp = NULL;
1775	}
1776	/*
1777	 * Release the data block if we have it.
1778	 */
1779	if (state->extravalid && state->extrablk.bp) {
1780		xfs_da_brelse(args->trans, state->extrablk.bp);
1781		state->extrablk.bp = NULL;
1782	}
1783	xfs_da_state_free(state);
1784	return rval;
1785}
1786
1787/*
1788 * Remove an entry from a node-format directory.
1789 */
1790int						/* error */
1791xfs_dir2_node_removename(
1792	xfs_da_args_t		*args)		/* operation arguments */
1793{
1794	xfs_da_state_blk_t	*blk;		/* leaf block */
1795	int			error;		/* error return value */
1796	int			rval;		/* operation return value */
1797	xfs_da_state_t		*state;		/* btree cursor */
1798
1799	trace_xfs_dir2_node_removename(args);
1800
1801	/*
1802	 * Allocate and initialize the btree cursor.
1803	 */
1804	state = xfs_da_state_alloc();
1805	state->args = args;
1806	state->mp = args->dp->i_mount;
1807	state->blocksize = state->mp->m_dirblksize;
1808	state->node_ents = state->mp->m_dir_node_ents;
1809	/*
1810	 * Look up the entry we're deleting, set up the cursor.
1811	 */
1812	error = xfs_da_node_lookup_int(state, &rval);
1813	if (error)
1814		rval = error;
1815	/*
1816	 * Didn't find it, upper layer screwed up.
1817	 */
1818	if (rval != EEXIST) {
1819		xfs_da_state_free(state);
1820		return rval;
1821	}
1822	blk = &state->path.blk[state->path.active - 1];
1823	ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
1824	ASSERT(state->extravalid);
1825	/*
1826	 * Remove the leaf and data entries.
1827	 * Extrablk refers to the data block.
1828	 */
1829	error = xfs_dir2_leafn_remove(args, blk->bp, blk->index,
1830		&state->extrablk, &rval);
1831	if (error)
1832		return error;
1833	/*
1834	 * Fix the hash values up the btree.
1835	 */
1836	xfs_da_fixhashpath(state, &state->path);
1837	/*
1838	 * If we need to join leaf blocks, do it.
1839	 */
1840	if (rval && state->path.active > 1)
1841		error = xfs_da_join(state);
1842	/*
1843	 * If no errors so far, try conversion to leaf format.
1844	 */
1845	if (!error)
1846		error = xfs_dir2_node_to_leaf(state);
1847	xfs_da_state_free(state);
1848	return error;
1849}
1850
1851/*
1852 * Replace an entry's inode number in a node-format directory.
1853 */
1854int						/* error */
1855xfs_dir2_node_replace(
1856	xfs_da_args_t		*args)		/* operation arguments */
1857{
1858	xfs_da_state_blk_t	*blk;		/* leaf block */
1859	xfs_dir2_data_hdr_t	*hdr;		/* data block header */
1860	xfs_dir2_data_entry_t	*dep;		/* data entry changed */
1861	int			error;		/* error return value */
1862	int			i;		/* btree level */
1863	xfs_ino_t		inum;		/* new inode number */
1864	xfs_dir2_leaf_t		*leaf;		/* leaf structure */
1865	xfs_dir2_leaf_entry_t	*lep;		/* leaf entry being changed */
1866	int			rval;		/* internal return value */
1867	xfs_da_state_t		*state;		/* btree cursor */
1868
1869	trace_xfs_dir2_node_replace(args);
1870
1871	/*
1872	 * Allocate and initialize the btree cursor.
1873	 */
1874	state = xfs_da_state_alloc();
1875	state->args = args;
1876	state->mp = args->dp->i_mount;
1877	state->blocksize = state->mp->m_dirblksize;
1878	state->node_ents = state->mp->m_dir_node_ents;
1879	inum = args->inumber;
1880	/*
1881	 * Lookup the entry to change in the btree.
1882	 */
1883	error = xfs_da_node_lookup_int(state, &rval);
1884	if (error) {
1885		rval = error;
1886	}
1887	/*
1888	 * It should be found, since the vnodeops layer has looked it up
1889	 * and locked it.  But paranoia is good.
1890	 */
1891	if (rval == EEXIST) {
1892		/*
1893		 * Find the leaf entry.
1894		 */
1895		blk = &state->path.blk[state->path.active - 1];
1896		ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
1897		leaf = blk->bp->data;
1898		lep = &leaf->ents[blk->index];
1899		ASSERT(state->extravalid);
1900		/*
1901		 * Point to the data entry.
1902		 */
1903		hdr = state->extrablk.bp->data;
1904		ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC));
1905		dep = (xfs_dir2_data_entry_t *)
1906		      ((char *)hdr +
1907		       xfs_dir2_dataptr_to_off(state->mp, be32_to_cpu(lep->address)));
1908		ASSERT(inum != be64_to_cpu(dep->inumber));
1909		/*
1910		 * Fill in the new inode number and log the entry.
1911		 */
1912		dep->inumber = cpu_to_be64(inum);
1913		xfs_dir2_data_log_entry(args->trans, state->extrablk.bp, dep);
1914		rval = 0;
1915	}
1916	/*
1917	 * Didn't find it, and we're holding a data block.  Drop it.
1918	 */
1919	else if (state->extravalid) {
1920		xfs_da_brelse(args->trans, state->extrablk.bp);
1921		state->extrablk.bp = NULL;
1922	}
1923	/*
1924	 * Release all the buffers in the cursor.
1925	 */
1926	for (i = 0; i < state->path.active; i++) {
1927		xfs_da_brelse(args->trans, state->path.blk[i].bp);
1928		state->path.blk[i].bp = NULL;
1929	}
1930	xfs_da_state_free(state);
1931	return rval;
1932}
1933
1934/*
1935 * Trim off a trailing empty freespace block.
1936 * Return (in rvalp) 1 if we did it, 0 if not.
1937 */
1938int						/* error */
1939xfs_dir2_node_trim_free(
1940	xfs_da_args_t		*args,		/* operation arguments */
1941	xfs_fileoff_t		fo,		/* free block number */
1942	int			*rvalp)		/* out: did something */
1943{
1944	xfs_dabuf_t		*bp;		/* freespace buffer */
1945	xfs_inode_t		*dp;		/* incore directory inode */
1946	int			error;		/* error return code */
1947	xfs_dir2_free_t		*free;		/* freespace structure */
1948	xfs_mount_t		*mp;		/* filesystem mount point */
1949	xfs_trans_t		*tp;		/* transaction pointer */
1950
1951	dp = args->dp;
1952	mp = dp->i_mount;
1953	tp = args->trans;
1954	/*
1955	 * Read the freespace block.
1956	 */
1957	if (unlikely(error = xfs_da_read_buf(tp, dp, (xfs_dablk_t)fo, -2, &bp,
1958			XFS_DATA_FORK))) {
1959		return error;
1960	}
1961
1962	/*
1963	 * There can be holes in freespace.  If fo is a hole, there's
1964	 * nothing to do.
1965	 */
1966	if (bp == NULL) {
1967		return 0;
1968	}
1969	free = bp->data;
1970	ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
1971	/*
1972	 * If there are used entries, there's nothing to do.
1973	 */
1974	if (be32_to_cpu(free->hdr.nused) > 0) {
1975		xfs_da_brelse(tp, bp);
1976		*rvalp = 0;
1977		return 0;
1978	}
1979	/*
1980	 * Blow the block away.
1981	 */
1982	if ((error =
1983	    xfs_dir2_shrink_inode(args, xfs_dir2_da_to_db(mp, (xfs_dablk_t)fo),
1984		    bp))) {
1985		/*
1986		 * Can't fail with ENOSPC since that only happens with no
1987		 * space reservation, when breaking up an extent into two
1988		 * pieces.  This is the last block of an extent.
1989		 */
1990		ASSERT(error != ENOSPC);
1991		xfs_da_brelse(tp, bp);
1992		return error;
1993	}
1994	/*
1995	 * Return that we succeeded.
1996	 */
1997	*rvalp = 1;
1998	return 0;
1999}