1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Copyright (C) 2018 Oracle.  All Rights Reserved.
4 * Author: Darrick J. Wong <darrick.wong@oracle.com>
5 */
6#include "xfs.h"
7#include "xfs_fs.h"
8#include "xfs_shared.h"
9#include "xfs_format.h"
10#include "xfs_trans_resv.h"
11#include "xfs_mount.h"
12#include "xfs_btree.h"
13#include "xfs_log_format.h"
14#include "xfs_trans.h"
15#include "xfs_sb.h"
16#include "xfs_alloc.h"
17#include "xfs_alloc_btree.h"
18#include "xfs_ialloc.h"
19#include "xfs_ialloc_btree.h"
20#include "xfs_rmap.h"
21#include "xfs_rmap_btree.h"
22#include "xfs_refcount_btree.h"
23#include "scrub/scrub.h"
24#include "scrub/common.h"
25#include "scrub/trace.h"
26#include "scrub/repair.h"
27#include "scrub/bitmap.h"
28
29/* Superblock */
30
31/* Repair the superblock. */
32int
33xrep_superblock(
34	struct xfs_scrub	*sc)
35{
36	struct xfs_mount	*mp = sc->mp;
37	struct xfs_buf		*bp;
38	xfs_agnumber_t		agno;
39	int			error;
40
41	/* Don't try to repair AG 0's sb; let xfs_repair deal with it. */
42	agno = sc->sm->sm_agno;
43	if (agno == 0)
44		return -EOPNOTSUPP;
45
46	error = xfs_sb_get_secondary(mp, sc->tp, agno, &bp);
47	if (error)
48		return error;
49
50	/* Copy AG 0's superblock to this one. */
51	xfs_buf_zero(bp, 0, BBTOB(bp->b_length));
52	xfs_sb_to_disk(bp->b_addr, &mp->m_sb);
53
54	/* Write this to disk. */
55	xfs_trans_buf_set_type(sc->tp, bp, XFS_BLFT_SB_BUF);
56	xfs_trans_log_buf(sc->tp, bp, 0, BBTOB(bp->b_length) - 1);
57	return error;
58}
59
60/* AGF */
61
62struct xrep_agf_allocbt {
63	struct xfs_scrub	*sc;
64	xfs_agblock_t		freeblks;
65	xfs_agblock_t		longest;
66};
67
68/* Record free space shape information. */
69STATIC int
70xrep_agf_walk_allocbt(
71	struct xfs_btree_cur		*cur,
72	struct xfs_alloc_rec_incore	*rec,
73	void				*priv)
74{
75	struct xrep_agf_allocbt		*raa = priv;
76	int				error = 0;
77
78	if (xchk_should_terminate(raa->sc, &error))
79		return error;
80
81	raa->freeblks += rec->ar_blockcount;
82	if (rec->ar_blockcount > raa->longest)
83		raa->longest = rec->ar_blockcount;
84	return error;
85}
86
87/* Does this AGFL block look sane? */
88STATIC int
89xrep_agf_check_agfl_block(
90	struct xfs_mount	*mp,
91	xfs_agblock_t		agbno,
92	void			*priv)
93{
94	struct xfs_scrub	*sc = priv;
95
96	if (!xfs_verify_agbno(mp, sc->sa.agno, agbno))
97		return -EFSCORRUPTED;
98	return 0;
99}
100
101/*
102 * Offset within the xrep_find_ag_btree array for each btree type.  Avoid the
103 * XFS_BTNUM_ names here to avoid creating a sparse array.
104 */
105enum {
106	XREP_AGF_BNOBT = 0,
107	XREP_AGF_CNTBT,
108	XREP_AGF_RMAPBT,
109	XREP_AGF_REFCOUNTBT,
110	XREP_AGF_END,
111	XREP_AGF_MAX
112};
113
114/* Check a btree root candidate. */
115static inline bool
116xrep_check_btree_root(
117	struct xfs_scrub		*sc,
118	struct xrep_find_ag_btree	*fab)
119{
120	struct xfs_mount		*mp = sc->mp;
121	xfs_agnumber_t			agno = sc->sm->sm_agno;
122
123	return xfs_verify_agbno(mp, agno, fab->root) &&
124	       fab->height <= XFS_BTREE_MAXLEVELS;
125}
126
127/*
128 * Given the btree roots described by *fab, find the roots, check them for
129 * sanity, and pass the root data back out via *fab.
130 *
131 * This is /also/ a chicken and egg problem because we have to use the rmapbt
132 * (rooted in the AGF) to find the btrees rooted in the AGF.  We also have no
133 * idea if the btrees make any sense.  If we hit obvious corruptions in those
134 * btrees we'll bail out.
135 */
136STATIC int
137xrep_agf_find_btrees(
138	struct xfs_scrub		*sc,
139	struct xfs_buf			*agf_bp,
140	struct xrep_find_ag_btree	*fab,
141	struct xfs_buf			*agfl_bp)
142{
143	struct xfs_agf			*old_agf = agf_bp->b_addr;
144	int				error;
145
146	/* Go find the root data. */
147	error = xrep_find_ag_btree_roots(sc, agf_bp, fab, agfl_bp);
148	if (error)
149		return error;
150
151	/* We must find the bnobt, cntbt, and rmapbt roots. */
152	if (!xrep_check_btree_root(sc, &fab[XREP_AGF_BNOBT]) ||
153	    !xrep_check_btree_root(sc, &fab[XREP_AGF_CNTBT]) ||
154	    !xrep_check_btree_root(sc, &fab[XREP_AGF_RMAPBT]))
155		return -EFSCORRUPTED;
156
157	/*
158	 * We relied on the rmapbt to reconstruct the AGF.  If we get a
159	 * different root then something's seriously wrong.
160	 */
161	if (fab[XREP_AGF_RMAPBT].root !=
162	    be32_to_cpu(old_agf->agf_roots[XFS_BTNUM_RMAPi]))
163		return -EFSCORRUPTED;
164
165	/* We must find the refcountbt root if that feature is enabled. */
166	if (xfs_sb_version_hasreflink(&sc->mp->m_sb) &&
167	    !xrep_check_btree_root(sc, &fab[XREP_AGF_REFCOUNTBT]))
168		return -EFSCORRUPTED;
169
170	return 0;
171}
172
173/*
174 * Reinitialize the AGF header, making an in-core copy of the old contents so
175 * that we know which in-core state needs to be reinitialized.
176 */
177STATIC void
178xrep_agf_init_header(
179	struct xfs_scrub	*sc,
180	struct xfs_buf		*agf_bp,
181	struct xfs_agf		*old_agf)
182{
183	struct xfs_mount	*mp = sc->mp;
184	struct xfs_agf		*agf = agf_bp->b_addr;
185
186	memcpy(old_agf, agf, sizeof(*old_agf));
187	memset(agf, 0, BBTOB(agf_bp->b_length));
188	agf->agf_magicnum = cpu_to_be32(XFS_AGF_MAGIC);
189	agf->agf_versionnum = cpu_to_be32(XFS_AGF_VERSION);
190	agf->agf_seqno = cpu_to_be32(sc->sa.agno);
191	agf->agf_length = cpu_to_be32(xfs_ag_block_count(mp, sc->sa.agno));
192	agf->agf_flfirst = old_agf->agf_flfirst;
193	agf->agf_fllast = old_agf->agf_fllast;
194	agf->agf_flcount = old_agf->agf_flcount;
195	if (xfs_sb_version_hascrc(&mp->m_sb))
196		uuid_copy(&agf->agf_uuid, &mp->m_sb.sb_meta_uuid);
197
198	/* Mark the incore AGF data stale until we're done fixing things. */
199	ASSERT(sc->sa.pag->pagf_init);
200	sc->sa.pag->pagf_init = 0;
201}
202
203/* Set btree root information in an AGF. */
204STATIC void
205xrep_agf_set_roots(
206	struct xfs_scrub		*sc,
207	struct xfs_agf			*agf,
208	struct xrep_find_ag_btree	*fab)
209{
210	agf->agf_roots[XFS_BTNUM_BNOi] =
211			cpu_to_be32(fab[XREP_AGF_BNOBT].root);
212	agf->agf_levels[XFS_BTNUM_BNOi] =
213			cpu_to_be32(fab[XREP_AGF_BNOBT].height);
214
215	agf->agf_roots[XFS_BTNUM_CNTi] =
216			cpu_to_be32(fab[XREP_AGF_CNTBT].root);
217	agf->agf_levels[XFS_BTNUM_CNTi] =
218			cpu_to_be32(fab[XREP_AGF_CNTBT].height);
219
220	agf->agf_roots[XFS_BTNUM_RMAPi] =
221			cpu_to_be32(fab[XREP_AGF_RMAPBT].root);
222	agf->agf_levels[XFS_BTNUM_RMAPi] =
223			cpu_to_be32(fab[XREP_AGF_RMAPBT].height);
224
225	if (xfs_sb_version_hasreflink(&sc->mp->m_sb)) {
226		agf->agf_refcount_root =
227				cpu_to_be32(fab[XREP_AGF_REFCOUNTBT].root);
228		agf->agf_refcount_level =
229				cpu_to_be32(fab[XREP_AGF_REFCOUNTBT].height);
230	}
231}
232
233/* Update all AGF fields which derive from btree contents. */
234STATIC int
235xrep_agf_calc_from_btrees(
236	struct xfs_scrub	*sc,
237	struct xfs_buf		*agf_bp)
238{
239	struct xrep_agf_allocbt	raa = { .sc = sc };
240	struct xfs_btree_cur	*cur = NULL;
241	struct xfs_agf		*agf = agf_bp->b_addr;
242	struct xfs_mount	*mp = sc->mp;
243	xfs_agblock_t		btreeblks;
244	xfs_agblock_t		blocks;
245	int			error;
246
247	/* Update the AGF counters from the bnobt. */
248	cur = xfs_allocbt_init_cursor(mp, sc->tp, agf_bp, sc->sa.agno,
249			XFS_BTNUM_BNO);
250	error = xfs_alloc_query_all(cur, xrep_agf_walk_allocbt, &raa);
251	if (error)
252		goto err;
253	error = xfs_btree_count_blocks(cur, &blocks);
254	if (error)
255		goto err;
256	xfs_btree_del_cursor(cur, error);
257	btreeblks = blocks - 1;
258	agf->agf_freeblks = cpu_to_be32(raa.freeblks);
259	agf->agf_longest = cpu_to_be32(raa.longest);
260
261	/* Update the AGF counters from the cntbt. */
262	cur = xfs_allocbt_init_cursor(mp, sc->tp, agf_bp, sc->sa.agno,
263			XFS_BTNUM_CNT);
264	error = xfs_btree_count_blocks(cur, &blocks);
265	if (error)
266		goto err;
267	xfs_btree_del_cursor(cur, error);
268	btreeblks += blocks - 1;
269
270	/* Update the AGF counters from the rmapbt. */
271	cur = xfs_rmapbt_init_cursor(mp, sc->tp, agf_bp, sc->sa.agno);
272	error = xfs_btree_count_blocks(cur, &blocks);
273	if (error)
274		goto err;
275	xfs_btree_del_cursor(cur, error);
276	agf->agf_rmap_blocks = cpu_to_be32(blocks);
277	btreeblks += blocks - 1;
278
279	agf->agf_btreeblks = cpu_to_be32(btreeblks);
280
281	/* Update the AGF counters from the refcountbt. */
282	if (xfs_sb_version_hasreflink(&mp->m_sb)) {
283		cur = xfs_refcountbt_init_cursor(mp, sc->tp, agf_bp,
284				sc->sa.agno);
285		error = xfs_btree_count_blocks(cur, &blocks);
286		if (error)
287			goto err;
288		xfs_btree_del_cursor(cur, error);
289		agf->agf_refcount_blocks = cpu_to_be32(blocks);
290	}
291
292	return 0;
293err:
294	xfs_btree_del_cursor(cur, error);
295	return error;
296}
297
298/* Commit the new AGF and reinitialize the incore state. */
299STATIC int
300xrep_agf_commit_new(
301	struct xfs_scrub	*sc,
302	struct xfs_buf		*agf_bp)
303{
304	struct xfs_perag	*pag;
305	struct xfs_agf		*agf = agf_bp->b_addr;
306
307	/* Trigger fdblocks recalculation */
308	xfs_force_summary_recalc(sc->mp);
309
310	/* Write this to disk. */
311	xfs_trans_buf_set_type(sc->tp, agf_bp, XFS_BLFT_AGF_BUF);
312	xfs_trans_log_buf(sc->tp, agf_bp, 0, BBTOB(agf_bp->b_length) - 1);
313
314	/* Now reinitialize the in-core counters we changed. */
315	pag = sc->sa.pag;
316	pag->pagf_btreeblks = be32_to_cpu(agf->agf_btreeblks);
317	pag->pagf_freeblks = be32_to_cpu(agf->agf_freeblks);
318	pag->pagf_longest = be32_to_cpu(agf->agf_longest);
319	pag->pagf_levels[XFS_BTNUM_BNOi] =
320			be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNOi]);
321	pag->pagf_levels[XFS_BTNUM_CNTi] =
322			be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNTi]);
323	pag->pagf_levels[XFS_BTNUM_RMAPi] =
324			be32_to_cpu(agf->agf_levels[XFS_BTNUM_RMAPi]);
325	pag->pagf_refcount_level = be32_to_cpu(agf->agf_refcount_level);
326	pag->pagf_init = 1;
327
328	return 0;
329}
330
331/* Repair the AGF. v5 filesystems only. */
332int
333xrep_agf(
334	struct xfs_scrub		*sc)
335{
336	struct xrep_find_ag_btree	fab[XREP_AGF_MAX] = {
337		[XREP_AGF_BNOBT] = {
338			.rmap_owner = XFS_RMAP_OWN_AG,
339			.buf_ops = &xfs_bnobt_buf_ops,
340		},
341		[XREP_AGF_CNTBT] = {
342			.rmap_owner = XFS_RMAP_OWN_AG,
343			.buf_ops = &xfs_cntbt_buf_ops,
344		},
345		[XREP_AGF_RMAPBT] = {
346			.rmap_owner = XFS_RMAP_OWN_AG,
347			.buf_ops = &xfs_rmapbt_buf_ops,
348		},
349		[XREP_AGF_REFCOUNTBT] = {
350			.rmap_owner = XFS_RMAP_OWN_REFC,
351			.buf_ops = &xfs_refcountbt_buf_ops,
352		},
353		[XREP_AGF_END] = {
354			.buf_ops = NULL,
355		},
356	};
357	struct xfs_agf			old_agf;
358	struct xfs_mount		*mp = sc->mp;
359	struct xfs_buf			*agf_bp;
360	struct xfs_buf			*agfl_bp;
361	struct xfs_agf			*agf;
362	int				error;
363
364	/* We require the rmapbt to rebuild anything. */
365	if (!xfs_sb_version_hasrmapbt(&mp->m_sb))
366		return -EOPNOTSUPP;
367
368	xchk_perag_get(sc->mp, &sc->sa);
369	/*
370	 * Make sure we have the AGF buffer, as scrub might have decided it
371	 * was corrupt after xfs_alloc_read_agf failed with -EFSCORRUPTED.
372	 */
373	error = xfs_trans_read_buf(mp, sc->tp, mp->m_ddev_targp,
374			XFS_AG_DADDR(mp, sc->sa.agno, XFS_AGF_DADDR(mp)),
375			XFS_FSS_TO_BB(mp, 1), 0, &agf_bp, NULL);
376	if (error)
377		return error;
378	agf_bp->b_ops = &xfs_agf_buf_ops;
379	agf = agf_bp->b_addr;
380
381	/*
382	 * Load the AGFL so that we can screen out OWN_AG blocks that are on
383	 * the AGFL now; these blocks might have once been part of the
384	 * bno/cnt/rmap btrees but are not now.  This is a chicken and egg
385	 * problem: the AGF is corrupt, so we have to trust the AGFL contents
386	 * because we can't do any serious cross-referencing with any of the
387	 * btrees rooted in the AGF.  If the AGFL contents are obviously bad
388	 * then we'll bail out.
389	 */
390	error = xfs_alloc_read_agfl(mp, sc->tp, sc->sa.agno, &agfl_bp);
391	if (error)
392		return error;
393
394	/*
395	 * Spot-check the AGFL blocks; if they're obviously corrupt then
396	 * there's nothing we can do but bail out.
397	 */
398	error = xfs_agfl_walk(sc->mp, agf_bp->b_addr, agfl_bp,
399			xrep_agf_check_agfl_block, sc);
400	if (error)
401		return error;
402
403	/*
404	 * Find the AGF btree roots.  This is also a chicken-and-egg situation;
405	 * see the function for more details.
406	 */
407	error = xrep_agf_find_btrees(sc, agf_bp, fab, agfl_bp);
408	if (error)
409		return error;
410
411	/* Start rewriting the header and implant the btrees we found. */
412	xrep_agf_init_header(sc, agf_bp, &old_agf);
413	xrep_agf_set_roots(sc, agf, fab);
414	error = xrep_agf_calc_from_btrees(sc, agf_bp);
415	if (error)
416		goto out_revert;
417
418	/* Commit the changes and reinitialize incore state. */
419	return xrep_agf_commit_new(sc, agf_bp);
420
421out_revert:
422	/* Mark the incore AGF state stale and revert the AGF. */
423	sc->sa.pag->pagf_init = 0;
424	memcpy(agf, &old_agf, sizeof(old_agf));
425	return error;
426}
427
428/* AGFL */
429
430struct xrep_agfl {
431	/* Bitmap of other OWN_AG metadata blocks. */
432	struct xbitmap		agmetablocks;
433
434	/* Bitmap of free space. */
435	struct xbitmap		*freesp;
436
437	struct xfs_scrub	*sc;
438};
439
440/* Record all OWN_AG (free space btree) information from the rmap data. */
441STATIC int
442xrep_agfl_walk_rmap(
443	struct xfs_btree_cur	*cur,
444	struct xfs_rmap_irec	*rec,
445	void			*priv)
446{
447	struct xrep_agfl	*ra = priv;
448	xfs_fsblock_t		fsb;
449	int			error = 0;
450
451	if (xchk_should_terminate(ra->sc, &error))
452		return error;
453
454	/* Record all the OWN_AG blocks. */
455	if (rec->rm_owner == XFS_RMAP_OWN_AG) {
456		fsb = XFS_AGB_TO_FSB(cur->bc_mp, cur->bc_ag.agno,
457				rec->rm_startblock);
458		error = xbitmap_set(ra->freesp, fsb, rec->rm_blockcount);
459		if (error)
460			return error;
461	}
462
463	return xbitmap_set_btcur_path(&ra->agmetablocks, cur);
464}
465
466/*
467 * Map out all the non-AGFL OWN_AG space in this AG so that we can deduce
468 * which blocks belong to the AGFL.
469 *
470 * Compute the set of old AGFL blocks by subtracting from the list of OWN_AG
471 * blocks the list of blocks owned by all other OWN_AG metadata (bnobt, cntbt,
472 * rmapbt).  These are the old AGFL blocks, so return that list and the number
473 * of blocks we're actually going to put back on the AGFL.
474 */
475STATIC int
476xrep_agfl_collect_blocks(
477	struct xfs_scrub	*sc,
478	struct xfs_buf		*agf_bp,
479	struct xbitmap		*agfl_extents,
480	xfs_agblock_t		*flcount)
481{
482	struct xrep_agfl	ra;
483	struct xfs_mount	*mp = sc->mp;
484	struct xfs_btree_cur	*cur;
485	int			error;
486
487	ra.sc = sc;
488	ra.freesp = agfl_extents;
489	xbitmap_init(&ra.agmetablocks);
490
491	/* Find all space used by the free space btrees & rmapbt. */
492	cur = xfs_rmapbt_init_cursor(mp, sc->tp, agf_bp, sc->sa.agno);
493	error = xfs_rmap_query_all(cur, xrep_agfl_walk_rmap, &ra);
494	if (error)
495		goto err;
496	xfs_btree_del_cursor(cur, error);
497
498	/* Find all blocks currently being used by the bnobt. */
499	cur = xfs_allocbt_init_cursor(mp, sc->tp, agf_bp, sc->sa.agno,
500			XFS_BTNUM_BNO);
501	error = xbitmap_set_btblocks(&ra.agmetablocks, cur);
502	if (error)
503		goto err;
504	xfs_btree_del_cursor(cur, error);
505
506	/* Find all blocks currently being used by the cntbt. */
507	cur = xfs_allocbt_init_cursor(mp, sc->tp, agf_bp, sc->sa.agno,
508			XFS_BTNUM_CNT);
509	error = xbitmap_set_btblocks(&ra.agmetablocks, cur);
510	if (error)
511		goto err;
512
513	xfs_btree_del_cursor(cur, error);
514
515	/*
516	 * Drop the freesp meta blocks that are in use by btrees.
517	 * The remaining blocks /should/ be AGFL blocks.
518	 */
519	error = xbitmap_disunion(agfl_extents, &ra.agmetablocks);
520	xbitmap_destroy(&ra.agmetablocks);
521	if (error)
522		return error;
523
524	/*
525	 * Calculate the new AGFL size.  If we found more blocks than fit in
526	 * the AGFL we'll free them later.
527	 */
528	*flcount = min_t(uint64_t, xbitmap_hweight(agfl_extents),
529			 xfs_agfl_size(mp));
530	return 0;
531
532err:
533	xbitmap_destroy(&ra.agmetablocks);
534	xfs_btree_del_cursor(cur, error);
535	return error;
536}
537
538/* Update the AGF and reset the in-core state. */
539STATIC void
540xrep_agfl_update_agf(
541	struct xfs_scrub	*sc,
542	struct xfs_buf		*agf_bp,
543	xfs_agblock_t		flcount)
544{
545	struct xfs_agf		*agf = agf_bp->b_addr;
546
547	ASSERT(flcount <= xfs_agfl_size(sc->mp));
548
549	/* Trigger fdblocks recalculation */
550	xfs_force_summary_recalc(sc->mp);
551
552	/* Update the AGF counters. */
553	if (sc->sa.pag->pagf_init)
554		sc->sa.pag->pagf_flcount = flcount;
555	agf->agf_flfirst = cpu_to_be32(0);
556	agf->agf_flcount = cpu_to_be32(flcount);
557	agf->agf_fllast = cpu_to_be32(flcount - 1);
558
559	xfs_alloc_log_agf(sc->tp, agf_bp,
560			XFS_AGF_FLFIRST | XFS_AGF_FLLAST | XFS_AGF_FLCOUNT);
561}
562
563/* Write out a totally new AGFL. */
564STATIC void
565xrep_agfl_init_header(
566	struct xfs_scrub	*sc,
567	struct xfs_buf		*agfl_bp,
568	struct xbitmap		*agfl_extents,
569	xfs_agblock_t		flcount)
570{
571	struct xfs_mount	*mp = sc->mp;
572	__be32			*agfl_bno;
573	struct xbitmap_range	*br;
574	struct xbitmap_range	*n;
575	struct xfs_agfl		*agfl;
576	xfs_agblock_t		agbno;
577	unsigned int		fl_off;
578
579	ASSERT(flcount <= xfs_agfl_size(mp));
580
581	/*
582	 * Start rewriting the header by setting the bno[] array to
583	 * NULLAGBLOCK, then setting AGFL header fields.
584	 */
585	agfl = XFS_BUF_TO_AGFL(agfl_bp);
586	memset(agfl, 0xFF, BBTOB(agfl_bp->b_length));
587	agfl->agfl_magicnum = cpu_to_be32(XFS_AGFL_MAGIC);
588	agfl->agfl_seqno = cpu_to_be32(sc->sa.agno);
589	uuid_copy(&agfl->agfl_uuid, &mp->m_sb.sb_meta_uuid);
590
591	/*
592	 * Fill the AGFL with the remaining blocks.  If agfl_extents has more
593	 * blocks than fit in the AGFL, they will be freed in a subsequent
594	 * step.
595	 */
596	fl_off = 0;
597	agfl_bno = xfs_buf_to_agfl_bno(agfl_bp);
598	for_each_xbitmap_extent(br, n, agfl_extents) {
599		agbno = XFS_FSB_TO_AGBNO(mp, br->start);
600
601		trace_xrep_agfl_insert(mp, sc->sa.agno, agbno, br->len);
602
603		while (br->len > 0 && fl_off < flcount) {
604			agfl_bno[fl_off] = cpu_to_be32(agbno);
605			fl_off++;
606			agbno++;
607
608			/*
609			 * We've now used br->start by putting it in the AGFL,
610			 * so bump br so that we don't reap the block later.
611			 */
612			br->start++;
613			br->len--;
614		}
615
616		if (br->len)
617			break;
618		list_del(&br->list);
619		kmem_free(br);
620	}
621
622	/* Write new AGFL to disk. */
623	xfs_trans_buf_set_type(sc->tp, agfl_bp, XFS_BLFT_AGFL_BUF);
624	xfs_trans_log_buf(sc->tp, agfl_bp, 0, BBTOB(agfl_bp->b_length) - 1);
625}
626
627/* Repair the AGFL. */
628int
629xrep_agfl(
630	struct xfs_scrub	*sc)
631{
632	struct xbitmap		agfl_extents;
633	struct xfs_mount	*mp = sc->mp;
634	struct xfs_buf		*agf_bp;
635	struct xfs_buf		*agfl_bp;
636	xfs_agblock_t		flcount;
637	int			error;
638
639	/* We require the rmapbt to rebuild anything. */
640	if (!xfs_sb_version_hasrmapbt(&mp->m_sb))
641		return -EOPNOTSUPP;
642
643	xchk_perag_get(sc->mp, &sc->sa);
644	xbitmap_init(&agfl_extents);
645
646	/*
647	 * Read the AGF so that we can query the rmapbt.  We hope that there's
648	 * nothing wrong with the AGF, but all the AG header repair functions
649	 * have this chicken-and-egg problem.
650	 */
651	error = xfs_alloc_read_agf(mp, sc->tp, sc->sa.agno, 0, &agf_bp);
652	if (error)
653		return error;
654
655	/*
656	 * Make sure we have the AGFL buffer, as scrub might have decided it
657	 * was corrupt after xfs_alloc_read_agfl failed with -EFSCORRUPTED.
658	 */
659	error = xfs_trans_read_buf(mp, sc->tp, mp->m_ddev_targp,
660			XFS_AG_DADDR(mp, sc->sa.agno, XFS_AGFL_DADDR(mp)),
661			XFS_FSS_TO_BB(mp, 1), 0, &agfl_bp, NULL);
662	if (error)
663		return error;
664	agfl_bp->b_ops = &xfs_agfl_buf_ops;
665
666	/* Gather all the extents we're going to put on the new AGFL. */
667	error = xrep_agfl_collect_blocks(sc, agf_bp, &agfl_extents, &flcount);
668	if (error)
669		goto err;
670
671	/*
672	 * Update AGF and AGFL.  We reset the global free block counter when
673	 * we adjust the AGF flcount (which can fail) so avoid updating any
674	 * buffers until we know that part works.
675	 */
676	xrep_agfl_update_agf(sc, agf_bp, flcount);
677	xrep_agfl_init_header(sc, agfl_bp, &agfl_extents, flcount);
678
679	/*
680	 * Ok, the AGFL should be ready to go now.  Roll the transaction to
681	 * make the new AGFL permanent before we start using it to return
682	 * freespace overflow to the freespace btrees.
683	 */
684	sc->sa.agf_bp = agf_bp;
685	sc->sa.agfl_bp = agfl_bp;
686	error = xrep_roll_ag_trans(sc);
687	if (error)
688		goto err;
689
690	/* Dump any AGFL overflow. */
691	error = xrep_reap_extents(sc, &agfl_extents, &XFS_RMAP_OINFO_AG,
692			XFS_AG_RESV_AGFL);
693err:
694	xbitmap_destroy(&agfl_extents);
695	return error;
696}
697
698/* AGI */
699
700/*
701 * Offset within the xrep_find_ag_btree array for each btree type.  Avoid the
702 * XFS_BTNUM_ names here to avoid creating a sparse array.
703 */
704enum {
705	XREP_AGI_INOBT = 0,
706	XREP_AGI_FINOBT,
707	XREP_AGI_END,
708	XREP_AGI_MAX
709};
710
711/*
712 * Given the inode btree roots described by *fab, find the roots, check them
713 * for sanity, and pass the root data back out via *fab.
714 */
715STATIC int
716xrep_agi_find_btrees(
717	struct xfs_scrub		*sc,
718	struct xrep_find_ag_btree	*fab)
719{
720	struct xfs_buf			*agf_bp;
721	struct xfs_mount		*mp = sc->mp;
722	int				error;
723
724	/* Read the AGF. */
725	error = xfs_alloc_read_agf(mp, sc->tp, sc->sa.agno, 0, &agf_bp);
726	if (error)
727		return error;
728
729	/* Find the btree roots. */
730	error = xrep_find_ag_btree_roots(sc, agf_bp, fab, NULL);
731	if (error)
732		return error;
733
734	/* We must find the inobt root. */
735	if (!xrep_check_btree_root(sc, &fab[XREP_AGI_INOBT]))
736		return -EFSCORRUPTED;
737
738	/* We must find the finobt root if that feature is enabled. */
739	if (xfs_sb_version_hasfinobt(&mp->m_sb) &&
740	    !xrep_check_btree_root(sc, &fab[XREP_AGI_FINOBT]))
741		return -EFSCORRUPTED;
742
743	return 0;
744}
745
746/*
747 * Reinitialize the AGI header, making an in-core copy of the old contents so
748 * that we know which in-core state needs to be reinitialized.
749 */
750STATIC void
751xrep_agi_init_header(
752	struct xfs_scrub	*sc,
753	struct xfs_buf		*agi_bp,
754	struct xfs_agi		*old_agi)
755{
756	struct xfs_agi		*agi = agi_bp->b_addr;
757	struct xfs_mount	*mp = sc->mp;
758
759	memcpy(old_agi, agi, sizeof(*old_agi));
760	memset(agi, 0, BBTOB(agi_bp->b_length));
761	agi->agi_magicnum = cpu_to_be32(XFS_AGI_MAGIC);
762	agi->agi_versionnum = cpu_to_be32(XFS_AGI_VERSION);
763	agi->agi_seqno = cpu_to_be32(sc->sa.agno);
764	agi->agi_length = cpu_to_be32(xfs_ag_block_count(mp, sc->sa.agno));
765	agi->agi_newino = cpu_to_be32(NULLAGINO);
766	agi->agi_dirino = cpu_to_be32(NULLAGINO);
767	if (xfs_sb_version_hascrc(&mp->m_sb))
768		uuid_copy(&agi->agi_uuid, &mp->m_sb.sb_meta_uuid);
769
770	/* We don't know how to fix the unlinked list yet. */
771	memcpy(&agi->agi_unlinked, &old_agi->agi_unlinked,
772			sizeof(agi->agi_unlinked));
773
774	/* Mark the incore AGF data stale until we're done fixing things. */
775	ASSERT(sc->sa.pag->pagi_init);
776	sc->sa.pag->pagi_init = 0;
777}
778
779/* Set btree root information in an AGI. */
780STATIC void
781xrep_agi_set_roots(
782	struct xfs_scrub		*sc,
783	struct xfs_agi			*agi,
784	struct xrep_find_ag_btree	*fab)
785{
786	agi->agi_root = cpu_to_be32(fab[XREP_AGI_INOBT].root);
787	agi->agi_level = cpu_to_be32(fab[XREP_AGI_INOBT].height);
788
789	if (xfs_sb_version_hasfinobt(&sc->mp->m_sb)) {
790		agi->agi_free_root = cpu_to_be32(fab[XREP_AGI_FINOBT].root);
791		agi->agi_free_level = cpu_to_be32(fab[XREP_AGI_FINOBT].height);
792	}
793}
794
795/* Update the AGI counters. */
796STATIC int
797xrep_agi_calc_from_btrees(
798	struct xfs_scrub	*sc,
799	struct xfs_buf		*agi_bp)
800{
801	struct xfs_btree_cur	*cur;
802	struct xfs_agi		*agi = agi_bp->b_addr;
803	struct xfs_mount	*mp = sc->mp;
804	xfs_agino_t		count;
805	xfs_agino_t		freecount;
806	int			error;
807
808	cur = xfs_inobt_init_cursor(mp, sc->tp, agi_bp, sc->sa.agno,
809			XFS_BTNUM_INO);
810	error = xfs_ialloc_count_inodes(cur, &count, &freecount);
811	if (error)
812		goto err;
813	if (xfs_sb_version_hasinobtcounts(&mp->m_sb)) {
814		xfs_agblock_t	blocks;
815
816		error = xfs_btree_count_blocks(cur, &blocks);
817		if (error)
818			goto err;
819		agi->agi_iblocks = cpu_to_be32(blocks);
820	}
821	xfs_btree_del_cursor(cur, error);
822
823	agi->agi_count = cpu_to_be32(count);
824	agi->agi_freecount = cpu_to_be32(freecount);
825
826	if (xfs_sb_version_hasfinobt(&mp->m_sb) &&
827	    xfs_sb_version_hasinobtcounts(&mp->m_sb)) {
828		xfs_agblock_t	blocks;
829
830		cur = xfs_inobt_init_cursor(mp, sc->tp, agi_bp, sc->sa.agno,
831				XFS_BTNUM_FINO);
832		if (error)
833			goto err;
834		error = xfs_btree_count_blocks(cur, &blocks);
835		if (error)
836			goto err;
837		xfs_btree_del_cursor(cur, error);
838		agi->agi_fblocks = cpu_to_be32(blocks);
839	}
840
841	return 0;
842err:
843	xfs_btree_del_cursor(cur, error);
844	return error;
845}
846
847/* Trigger reinitialization of the in-core data. */
848STATIC int
849xrep_agi_commit_new(
850	struct xfs_scrub	*sc,
851	struct xfs_buf		*agi_bp)
852{
853	struct xfs_perag	*pag;
854	struct xfs_agi		*agi = agi_bp->b_addr;
855
856	/* Trigger inode count recalculation */
857	xfs_force_summary_recalc(sc->mp);
858
859	/* Write this to disk. */
860	xfs_trans_buf_set_type(sc->tp, agi_bp, XFS_BLFT_AGI_BUF);
861	xfs_trans_log_buf(sc->tp, agi_bp, 0, BBTOB(agi_bp->b_length) - 1);
862
863	/* Now reinitialize the in-core counters if necessary. */
864	pag = sc->sa.pag;
865	pag->pagi_count = be32_to_cpu(agi->agi_count);
866	pag->pagi_freecount = be32_to_cpu(agi->agi_freecount);
867	pag->pagi_init = 1;
868
869	return 0;
870}
871
872/* Repair the AGI. */
873int
874xrep_agi(
875	struct xfs_scrub		*sc)
876{
877	struct xrep_find_ag_btree	fab[XREP_AGI_MAX] = {
878		[XREP_AGI_INOBT] = {
879			.rmap_owner = XFS_RMAP_OWN_INOBT,
880			.buf_ops = &xfs_inobt_buf_ops,
881		},
882		[XREP_AGI_FINOBT] = {
883			.rmap_owner = XFS_RMAP_OWN_INOBT,
884			.buf_ops = &xfs_finobt_buf_ops,
885		},
886		[XREP_AGI_END] = {
887			.buf_ops = NULL
888		},
889	};
890	struct xfs_agi			old_agi;
891	struct xfs_mount		*mp = sc->mp;
892	struct xfs_buf			*agi_bp;
893	struct xfs_agi			*agi;
894	int				error;
895
896	/* We require the rmapbt to rebuild anything. */
897	if (!xfs_sb_version_hasrmapbt(&mp->m_sb))
898		return -EOPNOTSUPP;
899
900	xchk_perag_get(sc->mp, &sc->sa);
901	/*
902	 * Make sure we have the AGI buffer, as scrub might have decided it
903	 * was corrupt after xfs_ialloc_read_agi failed with -EFSCORRUPTED.
904	 */
905	error = xfs_trans_read_buf(mp, sc->tp, mp->m_ddev_targp,
906			XFS_AG_DADDR(mp, sc->sa.agno, XFS_AGI_DADDR(mp)),
907			XFS_FSS_TO_BB(mp, 1), 0, &agi_bp, NULL);
908	if (error)
909		return error;
910	agi_bp->b_ops = &xfs_agi_buf_ops;
911	agi = agi_bp->b_addr;
912
913	/* Find the AGI btree roots. */
914	error = xrep_agi_find_btrees(sc, fab);
915	if (error)
916		return error;
917
918	/* Start rewriting the header and implant the btrees we found. */
919	xrep_agi_init_header(sc, agi_bp, &old_agi);
920	xrep_agi_set_roots(sc, agi, fab);
921	error = xrep_agi_calc_from_btrees(sc, agi_bp);
922	if (error)
923		goto out_revert;
924
925	/* Reinitialize in-core state. */
926	return xrep_agi_commit_new(sc, agi_bp);
927
928out_revert:
929	/* Mark the incore AGI state stale and revert the AGI. */
930	sc->sa.pag->pagi_init = 0;
931	memcpy(agi, &old_agi, sizeof(old_agi));
932	return error;
933}
934