1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
  4 * All Rights Reserved.
  5 */
  6#include "xfs.h"
  7#include "xfs_fs.h"
  8#include "xfs_shared.h"
  9#include "xfs_format.h"
 10#include "xfs_log_format.h"
 11#include "xfs_trans_resv.h"
 12#include "xfs_bit.h"
 13#include "xfs_mount.h"
 14#include "xfs_inode.h"
 15#include "xfs_trans.h"
 16#include "xfs_alloc.h"
 17#include "xfs_btree.h"
 18#include "xfs_btree_staging.h"
 19#include "xfs_bmap_btree.h"
 20#include "xfs_bmap.h"
 21#include "xfs_error.h"
 22#include "xfs_quota.h"
 23#include "xfs_trace.h"
 24#include "xfs_rmap.h"
 25#include "xfs_ag.h"
 26
 27static struct kmem_cache	*xfs_bmbt_cur_cache;
 28
 29void
 30xfs_bmbt_init_block(
 31	struct xfs_inode		*ip,
 32	struct xfs_btree_block		*buf,
 33	struct xfs_buf			*bp,
 34	__u16				level,
 35	__u16				numrecs)
 36{
 37	if (bp)
 38		xfs_btree_init_buf(ip->i_mount, bp, &xfs_bmbt_ops, level,
 39				numrecs, ip->i_ino);
 40	else
 41		xfs_btree_init_block(ip->i_mount, buf, &xfs_bmbt_ops, level,
 42				numrecs, ip->i_ino);
 43}
 44
 45/*
 46 * Convert on-disk form of btree root to in-memory form.
 47 */
 48void
 49xfs_bmdr_to_bmbt(
 50	struct xfs_inode	*ip,
 51	xfs_bmdr_block_t	*dblock,
 52	int			dblocklen,
 53	struct xfs_btree_block	*rblock,
 54	int			rblocklen)
 55{
 56	struct xfs_mount	*mp = ip->i_mount;
 57	int			dmxr;
 58	xfs_bmbt_key_t		*fkp;
 59	__be64			*fpp;
 60	xfs_bmbt_key_t		*tkp;
 61	__be64			*tpp;
 62
 63	xfs_bmbt_init_block(ip, rblock, NULL, 0, 0);
 
 
 64	rblock->bb_level = dblock->bb_level;
 65	ASSERT(be16_to_cpu(rblock->bb_level) > 0);
 66	rblock->bb_numrecs = dblock->bb_numrecs;
 67	dmxr = xfs_bmdr_maxrecs(dblocklen, 0);
 68	fkp = XFS_BMDR_KEY_ADDR(dblock, 1);
 69	tkp = XFS_BMBT_KEY_ADDR(mp, rblock, 1);
 70	fpp = XFS_BMDR_PTR_ADDR(dblock, 1, dmxr);
 71	tpp = XFS_BMAP_BROOT_PTR_ADDR(mp, rblock, 1, rblocklen);
 72	dmxr = be16_to_cpu(dblock->bb_numrecs);
 73	memcpy(tkp, fkp, sizeof(*fkp) * dmxr);
 74	memcpy(tpp, fpp, sizeof(*fpp) * dmxr);
 75}
 76
 77void
 78xfs_bmbt_disk_get_all(
 79	const struct xfs_bmbt_rec *rec,
 80	struct xfs_bmbt_irec	*irec)
 81{
 82	uint64_t		l0 = get_unaligned_be64(&rec->l0);
 83	uint64_t		l1 = get_unaligned_be64(&rec->l1);
 84
 85	irec->br_startoff = (l0 & xfs_mask64lo(64 - BMBT_EXNTFLAG_BITLEN)) >> 9;
 86	irec->br_startblock = ((l0 & xfs_mask64lo(9)) << 43) | (l1 >> 21);
 87	irec->br_blockcount = l1 & xfs_mask64lo(21);
 88	if (l0 >> (64 - BMBT_EXNTFLAG_BITLEN))
 89		irec->br_state = XFS_EXT_UNWRITTEN;
 90	else
 91		irec->br_state = XFS_EXT_NORM;
 92}
 93
 94/*
 95 * Extract the blockcount field from an on disk bmap extent record.
 96 */
 97xfs_filblks_t
 98xfs_bmbt_disk_get_blockcount(
 99	const struct xfs_bmbt_rec	*r)
100{
101	return (xfs_filblks_t)(be64_to_cpu(r->l1) & xfs_mask64lo(21));
102}
103
104/*
105 * Extract the startoff field from a disk format bmap extent record.
106 */
107xfs_fileoff_t
108xfs_bmbt_disk_get_startoff(
109	const struct xfs_bmbt_rec	*r)
110{
111	return ((xfs_fileoff_t)be64_to_cpu(r->l0) &
112		 xfs_mask64lo(64 - BMBT_EXNTFLAG_BITLEN)) >> 9;
113}
114
115/*
116 * Set all the fields in a bmap extent record from the uncompressed form.
117 */
118void
119xfs_bmbt_disk_set_all(
120	struct xfs_bmbt_rec	*r,
121	struct xfs_bmbt_irec	*s)
122{
123	int			extent_flag = (s->br_state != XFS_EXT_NORM);
124
125	ASSERT(s->br_state == XFS_EXT_NORM || s->br_state == XFS_EXT_UNWRITTEN);
126	ASSERT(!(s->br_startoff & xfs_mask64hi(64-BMBT_STARTOFF_BITLEN)));
127	ASSERT(!(s->br_blockcount & xfs_mask64hi(64-BMBT_BLOCKCOUNT_BITLEN)));
128	ASSERT(!(s->br_startblock & xfs_mask64hi(64-BMBT_STARTBLOCK_BITLEN)));
129
130	put_unaligned_be64(
131		((xfs_bmbt_rec_base_t)extent_flag << 63) |
132		 ((xfs_bmbt_rec_base_t)s->br_startoff << 9) |
133		 ((xfs_bmbt_rec_base_t)s->br_startblock >> 43), &r->l0);
134	put_unaligned_be64(
135		((xfs_bmbt_rec_base_t)s->br_startblock << 21) |
136		 ((xfs_bmbt_rec_base_t)s->br_blockcount &
137		  (xfs_bmbt_rec_base_t)xfs_mask64lo(21)), &r->l1);
138}
139
140/*
141 * Convert in-memory form of btree root to on-disk form.
142 */
143void
144xfs_bmbt_to_bmdr(
145	struct xfs_mount	*mp,
146	struct xfs_btree_block	*rblock,
147	int			rblocklen,
148	xfs_bmdr_block_t	*dblock,
149	int			dblocklen)
150{
151	int			dmxr;
152	xfs_bmbt_key_t		*fkp;
153	__be64			*fpp;
154	xfs_bmbt_key_t		*tkp;
155	__be64			*tpp;
156
157	if (xfs_has_crc(mp)) {
158		ASSERT(rblock->bb_magic == cpu_to_be32(XFS_BMAP_CRC_MAGIC));
159		ASSERT(uuid_equal(&rblock->bb_u.l.bb_uuid,
160		       &mp->m_sb.sb_meta_uuid));
161		ASSERT(rblock->bb_u.l.bb_blkno ==
162		       cpu_to_be64(XFS_BUF_DADDR_NULL));
163	} else
164		ASSERT(rblock->bb_magic == cpu_to_be32(XFS_BMAP_MAGIC));
165	ASSERT(rblock->bb_u.l.bb_leftsib == cpu_to_be64(NULLFSBLOCK));
166	ASSERT(rblock->bb_u.l.bb_rightsib == cpu_to_be64(NULLFSBLOCK));
167	ASSERT(rblock->bb_level != 0);
168	dblock->bb_level = rblock->bb_level;
169	dblock->bb_numrecs = rblock->bb_numrecs;
170	dmxr = xfs_bmdr_maxrecs(dblocklen, 0);
171	fkp = XFS_BMBT_KEY_ADDR(mp, rblock, 1);
172	tkp = XFS_BMDR_KEY_ADDR(dblock, 1);
173	fpp = XFS_BMAP_BROOT_PTR_ADDR(mp, rblock, 1, rblocklen);
174	tpp = XFS_BMDR_PTR_ADDR(dblock, 1, dmxr);
175	dmxr = be16_to_cpu(dblock->bb_numrecs);
176	memcpy(tkp, fkp, sizeof(*fkp) * dmxr);
177	memcpy(tpp, fpp, sizeof(*fpp) * dmxr);
178}
179
180STATIC struct xfs_btree_cur *
181xfs_bmbt_dup_cursor(
182	struct xfs_btree_cur	*cur)
183{
184	struct xfs_btree_cur	*new;
185
186	new = xfs_bmbt_init_cursor(cur->bc_mp, cur->bc_tp,
187			cur->bc_ino.ip, cur->bc_ino.whichfork);
188	new->bc_flags |= (cur->bc_flags &
189		(XFS_BTREE_BMBT_INVALID_OWNER | XFS_BTREE_BMBT_WASDEL));
 
 
 
 
 
190	return new;
191}
192
193STATIC void
194xfs_bmbt_update_cursor(
195	struct xfs_btree_cur	*src,
196	struct xfs_btree_cur	*dst)
197{
198	ASSERT((dst->bc_tp->t_highest_agno != NULLAGNUMBER) ||
199	       (dst->bc_ino.ip->i_diflags & XFS_DIFLAG_REALTIME));
200
201	dst->bc_bmap.allocated += src->bc_bmap.allocated;
202	dst->bc_tp->t_highest_agno = src->bc_tp->t_highest_agno;
203
204	src->bc_bmap.allocated = 0;
205}
206
207STATIC int
208xfs_bmbt_alloc_block(
209	struct xfs_btree_cur		*cur,
210	const union xfs_btree_ptr	*start,
211	union xfs_btree_ptr		*new,
212	int				*stat)
213{
214	struct xfs_alloc_arg	args;
215	int			error;
216
217	memset(&args, 0, sizeof(args));
218	args.tp = cur->bc_tp;
219	args.mp = cur->bc_mp;
 
220	xfs_rmap_ino_bmbt_owner(&args.oinfo, cur->bc_ino.ip->i_ino,
221			cur->bc_ino.whichfork);
222	args.minlen = args.maxlen = args.prod = 1;
223	args.wasdel = cur->bc_flags & XFS_BTREE_BMBT_WASDEL;
224	if (!args.wasdel && args.tp->t_blk_res == 0)
225		return -ENOSPC;
226
227	/*
228	 * If we are coming here from something like unwritten extent
229	 * conversion, there has been no data extent allocation already done, so
230	 * we have to ensure that we attempt to locate the entire set of bmbt
231	 * allocations in the same AG, as xfs_bmapi_write() would have reserved.
232	 */
233	if (cur->bc_tp->t_highest_agno == NULLAGNUMBER)
234		args.minleft = xfs_bmapi_minleft(cur->bc_tp, cur->bc_ino.ip,
235					cur->bc_ino.whichfork);
 
 
 
 
 
 
 
 
 
 
 
236
237	error = xfs_alloc_vextent_start_ag(&args, be64_to_cpu(start->l));
 
 
 
 
 
 
238	if (error)
239		return error;
240
241	if (args.fsbno == NULLFSBLOCK && args.minleft) {
242		/*
243		 * Could not find an AG with enough free space to satisfy
244		 * a full btree split.  Try again and if
245		 * successful activate the lowspace algorithm.
246		 */
247		args.minleft = 0;
248		error = xfs_alloc_vextent_start_ag(&args, 0);
 
249		if (error)
250			return error;
251		cur->bc_tp->t_flags |= XFS_TRANS_LOWMODE;
252	}
253	if (WARN_ON_ONCE(args.fsbno == NULLFSBLOCK)) {
254		*stat = 0;
255		return 0;
256	}
257
258	ASSERT(args.len == 1);
259	cur->bc_bmap.allocated++;
260	cur->bc_ino.ip->i_nblocks++;
 
261	xfs_trans_log_inode(args.tp, cur->bc_ino.ip, XFS_ILOG_CORE);
262	xfs_trans_mod_dquot_byino(args.tp, cur->bc_ino.ip,
263			XFS_TRANS_DQ_BCOUNT, 1L);
264
265	new->l = cpu_to_be64(args.fsbno);
266
267	*stat = 1;
268	return 0;
 
 
 
269}
270
271STATIC int
272xfs_bmbt_free_block(
273	struct xfs_btree_cur	*cur,
274	struct xfs_buf		*bp)
275{
276	struct xfs_mount	*mp = cur->bc_mp;
277	struct xfs_inode	*ip = cur->bc_ino.ip;
278	struct xfs_trans	*tp = cur->bc_tp;
279	xfs_fsblock_t		fsbno = XFS_DADDR_TO_FSB(mp, xfs_buf_daddr(bp));
280	struct xfs_owner_info	oinfo;
281	int			error;
282
283	xfs_rmap_ino_bmbt_owner(&oinfo, ip->i_ino, cur->bc_ino.whichfork);
284	error = xfs_free_extent_later(cur->bc_tp, fsbno, 1, &oinfo,
285			XFS_AG_RESV_NONE, false);
286	if (error)
287		return error;
288
289	ip->i_nblocks--;
290	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
291	xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, -1L);
292	return 0;
293}
294
295STATIC int
296xfs_bmbt_get_minrecs(
297	struct xfs_btree_cur	*cur,
298	int			level)
299{
300	if (level == cur->bc_nlevels - 1) {
301		struct xfs_ifork	*ifp = xfs_btree_ifork_ptr(cur);
 
 
 
302
303		return xfs_bmbt_maxrecs(cur->bc_mp,
304					ifp->if_broot_bytes, level == 0) / 2;
305	}
306
307	return cur->bc_mp->m_bmap_dmnr[level != 0];
308}
309
310int
311xfs_bmbt_get_maxrecs(
312	struct xfs_btree_cur	*cur,
313	int			level)
314{
315	if (level == cur->bc_nlevels - 1) {
316		struct xfs_ifork	*ifp = xfs_btree_ifork_ptr(cur);
 
 
 
317
318		return xfs_bmbt_maxrecs(cur->bc_mp,
319					ifp->if_broot_bytes, level == 0);
320	}
321
322	return cur->bc_mp->m_bmap_dmxr[level != 0];
323
324}
325
326/*
327 * Get the maximum records we could store in the on-disk format.
328 *
329 * For non-root nodes this is equivalent to xfs_bmbt_get_maxrecs, but
330 * for the root node this checks the available space in the dinode fork
331 * so that we can resize the in-memory buffer to match it.  After a
332 * resize to the maximum size this function returns the same value
333 * as xfs_bmbt_get_maxrecs for the root node, too.
334 */
335STATIC int
336xfs_bmbt_get_dmaxrecs(
337	struct xfs_btree_cur	*cur,
338	int			level)
339{
340	if (level != cur->bc_nlevels - 1)
341		return cur->bc_mp->m_bmap_dmxr[level != 0];
342	return xfs_bmdr_maxrecs(cur->bc_ino.forksize, level == 0);
343}
344
345STATIC void
346xfs_bmbt_init_key_from_rec(
347	union xfs_btree_key		*key,
348	const union xfs_btree_rec	*rec)
349{
350	key->bmbt.br_startoff =
351		cpu_to_be64(xfs_bmbt_disk_get_startoff(&rec->bmbt));
352}
353
354STATIC void
355xfs_bmbt_init_high_key_from_rec(
356	union xfs_btree_key		*key,
357	const union xfs_btree_rec	*rec)
358{
359	key->bmbt.br_startoff = cpu_to_be64(
360			xfs_bmbt_disk_get_startoff(&rec->bmbt) +
361			xfs_bmbt_disk_get_blockcount(&rec->bmbt) - 1);
362}
363
364STATIC void
365xfs_bmbt_init_rec_from_cur(
366	struct xfs_btree_cur	*cur,
367	union xfs_btree_rec	*rec)
368{
369	xfs_bmbt_disk_set_all(&rec->bmbt, &cur->bc_rec.b);
370}
371
 
 
 
 
 
 
 
 
372STATIC int64_t
373xfs_bmbt_key_diff(
374	struct xfs_btree_cur		*cur,
375	const union xfs_btree_key	*key)
376{
377	return (int64_t)be64_to_cpu(key->bmbt.br_startoff) -
378				      cur->bc_rec.b.br_startoff;
379}
380
381STATIC int64_t
382xfs_bmbt_diff_two_keys(
383	struct xfs_btree_cur		*cur,
384	const union xfs_btree_key	*k1,
385	const union xfs_btree_key	*k2,
386	const union xfs_btree_key	*mask)
387{
388	uint64_t			a = be64_to_cpu(k1->bmbt.br_startoff);
389	uint64_t			b = be64_to_cpu(k2->bmbt.br_startoff);
390
391	ASSERT(!mask || mask->bmbt.br_startoff);
392
393	/*
394	 * Note: This routine previously casted a and b to int64 and subtracted
395	 * them to generate a result.  This lead to problems if b was the
396	 * "maximum" key value (all ones) being signed incorrectly, hence this
397	 * somewhat less efficient version.
398	 */
399	if (a > b)
400		return 1;
401	if (b > a)
402		return -1;
403	return 0;
404}
405
406static xfs_failaddr_t
407xfs_bmbt_verify(
408	struct xfs_buf		*bp)
409{
410	struct xfs_mount	*mp = bp->b_mount;
411	struct xfs_btree_block	*block = XFS_BUF_TO_BLOCK(bp);
412	xfs_failaddr_t		fa;
413	unsigned int		level;
414
415	if (!xfs_verify_magic(bp, block->bb_magic))
416		return __this_address;
417
418	if (xfs_has_crc(mp)) {
419		/*
420		 * XXX: need a better way of verifying the owner here. Right now
421		 * just make sure there has been one set.
422		 */
423		fa = xfs_btree_fsblock_v5hdr_verify(bp, XFS_RMAP_OWN_UNKNOWN);
424		if (fa)
425			return fa;
426	}
427
428	/*
429	 * numrecs and level verification.
430	 *
431	 * We don't know what fork we belong to, so just verify that the level
432	 * is less than the maximum of the two. Later checks will be more
433	 * precise.
434	 */
435	level = be16_to_cpu(block->bb_level);
436	if (level > max(mp->m_bm_maxlevels[0], mp->m_bm_maxlevels[1]))
437		return __this_address;
438
439	return xfs_btree_fsblock_verify(bp, mp->m_bmap_dmxr[level != 0]);
440}
441
442static void
443xfs_bmbt_read_verify(
444	struct xfs_buf	*bp)
445{
446	xfs_failaddr_t	fa;
447
448	if (!xfs_btree_fsblock_verify_crc(bp))
449		xfs_verifier_error(bp, -EFSBADCRC, __this_address);
450	else {
451		fa = xfs_bmbt_verify(bp);
452		if (fa)
453			xfs_verifier_error(bp, -EFSCORRUPTED, fa);
454	}
455
456	if (bp->b_error)
457		trace_xfs_btree_corrupt(bp, _RET_IP_);
458}
459
460static void
461xfs_bmbt_write_verify(
462	struct xfs_buf	*bp)
463{
464	xfs_failaddr_t	fa;
465
466	fa = xfs_bmbt_verify(bp);
467	if (fa) {
468		trace_xfs_btree_corrupt(bp, _RET_IP_);
469		xfs_verifier_error(bp, -EFSCORRUPTED, fa);
470		return;
471	}
472	xfs_btree_fsblock_calc_crc(bp);
473}
474
475const struct xfs_buf_ops xfs_bmbt_buf_ops = {
476	.name = "xfs_bmbt",
477	.magic = { cpu_to_be32(XFS_BMAP_MAGIC),
478		   cpu_to_be32(XFS_BMAP_CRC_MAGIC) },
479	.verify_read = xfs_bmbt_read_verify,
480	.verify_write = xfs_bmbt_write_verify,
481	.verify_struct = xfs_bmbt_verify,
482};
483
484
485STATIC int
486xfs_bmbt_keys_inorder(
487	struct xfs_btree_cur		*cur,
488	const union xfs_btree_key	*k1,
489	const union xfs_btree_key	*k2)
490{
491	return be64_to_cpu(k1->bmbt.br_startoff) <
492		be64_to_cpu(k2->bmbt.br_startoff);
493}
494
495STATIC int
496xfs_bmbt_recs_inorder(
497	struct xfs_btree_cur		*cur,
498	const union xfs_btree_rec	*r1,
499	const union xfs_btree_rec	*r2)
500{
501	return xfs_bmbt_disk_get_startoff(&r1->bmbt) +
502		xfs_bmbt_disk_get_blockcount(&r1->bmbt) <=
503		xfs_bmbt_disk_get_startoff(&r2->bmbt);
504}
505
506STATIC enum xbtree_key_contig
507xfs_bmbt_keys_contiguous(
508	struct xfs_btree_cur		*cur,
509	const union xfs_btree_key	*key1,
510	const union xfs_btree_key	*key2,
511	const union xfs_btree_key	*mask)
512{
513	ASSERT(!mask || mask->bmbt.br_startoff);
514
515	return xbtree_key_contig(be64_to_cpu(key1->bmbt.br_startoff),
516				 be64_to_cpu(key2->bmbt.br_startoff));
517}
518
519const struct xfs_btree_ops xfs_bmbt_ops = {
520	.name			= "bmap",
521	.type			= XFS_BTREE_TYPE_INODE,
522
523	.rec_len		= sizeof(xfs_bmbt_rec_t),
524	.key_len		= sizeof(xfs_bmbt_key_t),
525	.ptr_len		= XFS_BTREE_LONG_PTR_LEN,
526
527	.lru_refs		= XFS_BMAP_BTREE_REF,
528	.statoff		= XFS_STATS_CALC_INDEX(xs_bmbt_2),
529
530	.dup_cursor		= xfs_bmbt_dup_cursor,
531	.update_cursor		= xfs_bmbt_update_cursor,
532	.alloc_block		= xfs_bmbt_alloc_block,
533	.free_block		= xfs_bmbt_free_block,
534	.get_maxrecs		= xfs_bmbt_get_maxrecs,
535	.get_minrecs		= xfs_bmbt_get_minrecs,
536	.get_dmaxrecs		= xfs_bmbt_get_dmaxrecs,
537	.init_key_from_rec	= xfs_bmbt_init_key_from_rec,
538	.init_high_key_from_rec	= xfs_bmbt_init_high_key_from_rec,
539	.init_rec_from_cur	= xfs_bmbt_init_rec_from_cur,
 
540	.key_diff		= xfs_bmbt_key_diff,
541	.diff_two_keys		= xfs_bmbt_diff_two_keys,
542	.buf_ops		= &xfs_bmbt_buf_ops,
543	.keys_inorder		= xfs_bmbt_keys_inorder,
544	.recs_inorder		= xfs_bmbt_recs_inorder,
545	.keys_contiguous	= xfs_bmbt_keys_contiguous,
546};
547
548/*
549 * Create a new bmap btree cursor.
550 *
551 * For staging cursors -1 in passed in whichfork.
552 */
553struct xfs_btree_cur *
554xfs_bmbt_init_cursor(
555	struct xfs_mount	*mp,
556	struct xfs_trans	*tp,
557	struct xfs_inode	*ip,
558	int			whichfork)
559{
 
560	struct xfs_btree_cur	*cur;
561	unsigned int		maxlevels;
562
563	ASSERT(whichfork != XFS_COW_FORK);
564
565	/*
566	 * The Data fork always has larger maxlevel, so use that for staging
567	 * cursors.
568	 */
569	switch (whichfork) {
570	case XFS_STAGING_FORK:
571		maxlevels = mp->m_bm_maxlevels[XFS_DATA_FORK];
572		break;
573	default:
574		maxlevels = mp->m_bm_maxlevels[whichfork];
575		break;
576	}
577	cur = xfs_btree_alloc_cursor(mp, tp, &xfs_bmbt_ops, maxlevels,
578			xfs_bmbt_cur_cache);
 
579	cur->bc_ino.ip = ip;
 
 
580	cur->bc_ino.whichfork = whichfork;
581	cur->bc_bmap.allocated = 0;
582	if (whichfork != XFS_STAGING_FORK) {
583		struct xfs_ifork	*ifp = xfs_ifork_ptr(ip, whichfork);
584
585		cur->bc_nlevels = be16_to_cpu(ifp->if_broot->bb_level) + 1;
586		cur->bc_ino.forksize = xfs_inode_fork_size(ip, whichfork);
587	}
588	return cur;
589}
590
591/* Calculate number of records in a block mapping btree block. */
592static inline unsigned int
593xfs_bmbt_block_maxrecs(
594	unsigned int		blocklen,
595	bool			leaf)
596{
597	if (leaf)
598		return blocklen / sizeof(xfs_bmbt_rec_t);
599	return blocklen / (sizeof(xfs_bmbt_key_t) + sizeof(xfs_bmbt_ptr_t));
600}
601
602/*
603 * Swap in the new inode fork root.  Once we pass this point the newly rebuilt
604 * mappings are in place and we have to kill off any old btree blocks.
605 */
606void
607xfs_bmbt_commit_staged_btree(
608	struct xfs_btree_cur	*cur,
609	struct xfs_trans	*tp,
610	int			whichfork)
611{
612	struct xbtree_ifakeroot	*ifake = cur->bc_ino.ifake;
613	struct xfs_ifork	*ifp;
614	static const short	brootflag[2] = {XFS_ILOG_DBROOT, XFS_ILOG_ABROOT};
615	static const short	extflag[2] = {XFS_ILOG_DEXT, XFS_ILOG_AEXT};
616	int			flags = XFS_ILOG_CORE;
617
618	ASSERT(cur->bc_flags & XFS_BTREE_STAGING);
619	ASSERT(whichfork != XFS_COW_FORK);
620
621	/*
622	 * Free any resources hanging off the real fork, then shallow-copy the
623	 * staging fork's contents into the real fork to transfer everything
624	 * we just built.
625	 */
626	ifp = xfs_ifork_ptr(cur->bc_ino.ip, whichfork);
627	xfs_idestroy_fork(ifp);
628	memcpy(ifp, ifake->if_fork, sizeof(struct xfs_ifork));
629
630	switch (ifp->if_format) {
631	case XFS_DINODE_FMT_EXTENTS:
632		flags |= extflag[whichfork];
633		break;
634	case XFS_DINODE_FMT_BTREE:
635		flags |= brootflag[whichfork];
636		break;
637	default:
638		ASSERT(0);
639		break;
640	}
641	xfs_trans_log_inode(tp, cur->bc_ino.ip, flags);
642	xfs_btree_commit_ifakeroot(cur, tp, whichfork);
643}
644
645/*
646 * Calculate number of records in a bmap btree block.
647 */
648int
649xfs_bmbt_maxrecs(
650	struct xfs_mount	*mp,
651	int			blocklen,
652	int			leaf)
653{
654	blocklen -= XFS_BMBT_BLOCK_LEN(mp);
655	return xfs_bmbt_block_maxrecs(blocklen, leaf);
656}
657
658/*
659 * Calculate the maximum possible height of the btree that the on-disk format
660 * supports. This is used for sizing structures large enough to support every
661 * possible configuration of a filesystem that might get mounted.
662 */
663unsigned int
664xfs_bmbt_maxlevels_ondisk(void)
665{
666	unsigned int		minrecs[2];
667	unsigned int		blocklen;
668
669	blocklen = min(XFS_MIN_BLOCKSIZE - XFS_BTREE_SBLOCK_LEN,
670		       XFS_MIN_CRC_BLOCKSIZE - XFS_BTREE_SBLOCK_CRC_LEN);
671
672	minrecs[0] = xfs_bmbt_block_maxrecs(blocklen, true) / 2;
673	minrecs[1] = xfs_bmbt_block_maxrecs(blocklen, false) / 2;
674
675	/* One extra level for the inode root. */
676	return xfs_btree_compute_maxlevels(minrecs,
677			XFS_MAX_EXTCNT_DATA_FORK_LARGE) + 1;
678}
679
680/*
681 * Calculate number of records in a bmap btree inode root.
682 */
683int
684xfs_bmdr_maxrecs(
685	int			blocklen,
686	int			leaf)
687{
688	blocklen -= sizeof(xfs_bmdr_block_t);
689
690	if (leaf)
691		return blocklen / sizeof(xfs_bmdr_rec_t);
692	return blocklen / (sizeof(xfs_bmdr_key_t) + sizeof(xfs_bmdr_ptr_t));
693}
694
695/*
696 * Change the owner of a btree format fork fo the inode passed in. Change it to
697 * the owner of that is passed in so that we can change owners before or after
698 * we switch forks between inodes. The operation that the caller is doing will
699 * determine whether is needs to change owner before or after the switch.
700 *
701 * For demand paged transactional modification, the fork switch should be done
702 * after reading in all the blocks, modifying them and pinning them in the
703 * transaction. For modification when the buffers are already pinned in memory,
704 * the fork switch can be done before changing the owner as we won't need to
705 * validate the owner until the btree buffers are unpinned and writes can occur
706 * again.
707 *
708 * For recovery based ownership change, there is no transactional context and
709 * so a buffer list must be supplied so that we can record the buffers that we
710 * modified for the caller to issue IO on.
711 */
712int
713xfs_bmbt_change_owner(
714	struct xfs_trans	*tp,
715	struct xfs_inode	*ip,
716	int			whichfork,
717	xfs_ino_t		new_owner,
718	struct list_head	*buffer_list)
719{
720	struct xfs_btree_cur	*cur;
721	int			error;
722
723	ASSERT(tp || buffer_list);
724	ASSERT(!(tp && buffer_list));
725	ASSERT(xfs_ifork_ptr(ip, whichfork)->if_format == XFS_DINODE_FMT_BTREE);
726
727	cur = xfs_bmbt_init_cursor(ip->i_mount, tp, ip, whichfork);
728	cur->bc_flags |= XFS_BTREE_BMBT_INVALID_OWNER;
 
 
729
730	error = xfs_btree_change_owner(cur, new_owner, buffer_list);
731	xfs_btree_del_cursor(cur, error);
732	return error;
733}
734
735/* Calculate the bmap btree size for some records. */
736unsigned long long
737xfs_bmbt_calc_size(
738	struct xfs_mount	*mp,
739	unsigned long long	len)
740{
741	return xfs_btree_calc_size(mp->m_bmap_dmnr, len);
742}
743
744int __init
745xfs_bmbt_init_cur_cache(void)
746{
747	xfs_bmbt_cur_cache = kmem_cache_create("xfs_bmbt_cur",
748			xfs_btree_cur_sizeof(xfs_bmbt_maxlevels_ondisk()),
749			0, 0, NULL);
750
751	if (!xfs_bmbt_cur_cache)
752		return -ENOMEM;
753	return 0;
754}
755
756void
757xfs_bmbt_destroy_cur_cache(void)
758{
759	kmem_cache_destroy(xfs_bmbt_cur_cache);
760	xfs_bmbt_cur_cache = NULL;
761}