xref: /linux/fs/xfs/scrub/rtsummary_repair.c (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (c) 2020-2024 Oracle.  All Rights Reserved.
4  * Author: Darrick J. Wong <djwong@kernel.org>
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_rtalloc.h"
16 #include "xfs_inode.h"
17 #include "xfs_bit.h"
18 #include "xfs_bmap.h"
19 #include "xfs_bmap_btree.h"
20 #include "xfs_exchmaps.h"
21 #include "xfs_rtbitmap.h"
22 #include "scrub/scrub.h"
23 #include "scrub/common.h"
24 #include "scrub/trace.h"
25 #include "scrub/repair.h"
26 #include "scrub/tempfile.h"
27 #include "scrub/tempexch.h"
28 #include "scrub/reap.h"
29 #include "scrub/xfile.h"
30 #include "scrub/rtsummary.h"
31 
32 /* Set us up to repair the rtsummary file. */
33 int
34 xrep_setup_rtsummary(
35 	struct xfs_scrub	*sc,
36 	struct xchk_rtsummary	*rts)
37 {
38 	struct xfs_mount	*mp = sc->mp;
39 	unsigned long long	blocks;
40 	int			error;
41 
42 	error = xrep_tempfile_create(sc, S_IFREG);
43 	if (error)
44 		return error;
45 
46 	/*
47 	 * If we're doing a repair, we reserve enough blocks to write out a
48 	 * completely new summary file, plus twice as many blocks as we would
49 	 * need if we can only allocate one block per data fork mapping.  This
50 	 * should cover the preallocation of the temporary file and exchanging
51 	 * the extent mappings.
52 	 *
53 	 * We cannot use xfs_exchmaps_estimate because we have not yet
54 	 * constructed the replacement rtsummary and therefore do not know how
55 	 * many extents it will use.  By the time we do, we will have a dirty
56 	 * transaction (which we cannot drop because we cannot drop the
57 	 * rtsummary ILOCK) and cannot ask for more reservation.
58 	 */
59 	blocks = XFS_B_TO_FSB(mp, mp->m_rsumsize);
60 	blocks += xfs_bmbt_calc_size(mp, blocks) * 2;
61 	if (blocks > UINT_MAX)
62 		return -EOPNOTSUPP;
63 
64 	rts->resblks += blocks;
65 	return 0;
66 }
67 
68 static int
69 xrep_rtsummary_prep_buf(
70 	struct xfs_scrub	*sc,
71 	struct xfs_buf		*bp,
72 	void			*data)
73 {
74 	struct xchk_rtsummary	*rts = data;
75 	struct xfs_mount	*mp = sc->mp;
76 	union xfs_suminfo_raw	*ondisk;
77 	int			error;
78 
79 	rts->args.mp = sc->mp;
80 	rts->args.tp = sc->tp;
81 	rts->args.sumbp = bp;
82 	ondisk = xfs_rsumblock_infoptr(&rts->args, 0);
83 	rts->args.sumbp = NULL;
84 
85 	bp->b_ops = &xfs_rtbuf_ops;
86 
87 	error = xfsum_copyout(sc, rts->prep_wordoff, ondisk, mp->m_blockwsize);
88 	if (error)
89 		return error;
90 
91 	rts->prep_wordoff += mp->m_blockwsize;
92 	xfs_trans_buf_set_type(sc->tp, bp, XFS_BLFT_RTSUMMARY_BUF);
93 	return 0;
94 }
95 
96 /* Repair the realtime summary. */
97 int
98 xrep_rtsummary(
99 	struct xfs_scrub	*sc)
100 {
101 	struct xchk_rtsummary	*rts = sc->buf;
102 	struct xfs_mount	*mp = sc->mp;
103 	xfs_filblks_t		rsumblocks;
104 	int			error;
105 
106 	/* We require the rmapbt to rebuild anything. */
107 	if (!xfs_has_rmapbt(mp))
108 		return -EOPNOTSUPP;
109 	/* We require atomic file exchange range to rebuild anything. */
110 	if (!xfs_has_exchange_range(mp))
111 		return -EOPNOTSUPP;
112 
113 	/* Walk away if we disagree on the size of the rt bitmap. */
114 	if (rts->rbmblocks != mp->m_sb.sb_rbmblocks)
115 		return 0;
116 
117 	/* Make sure any problems with the fork are fixed. */
118 	error = xrep_metadata_inode_forks(sc);
119 	if (error)
120 		return error;
121 
122 	/*
123 	 * Try to take ILOCK_EXCL of the temporary file.  We had better be the
124 	 * only ones holding onto this inode, but we can't block while holding
125 	 * the rtsummary file's ILOCK_EXCL.
126 	 */
127 	while (!xrep_tempfile_ilock_nowait(sc)) {
128 		if (xchk_should_terminate(sc, &error))
129 			return error;
130 		delay(1);
131 	}
132 
133 	/* Make sure we have space allocated for the entire summary file. */
134 	rsumblocks = XFS_B_TO_FSB(mp, rts->rsumsize);
135 	xfs_trans_ijoin(sc->tp, sc->ip, 0);
136 	xfs_trans_ijoin(sc->tp, sc->tempip, 0);
137 	error = xrep_tempfile_prealloc(sc, 0, rsumblocks);
138 	if (error)
139 		return error;
140 
141 	/* Last chance to abort before we start committing fixes. */
142 	if (xchk_should_terminate(sc, &error))
143 		return error;
144 
145 	/* Copy the rtsummary file that we generated. */
146 	error = xrep_tempfile_copyin(sc, 0, rsumblocks,
147 			xrep_rtsummary_prep_buf, rts);
148 	if (error)
149 		return error;
150 	error = xrep_tempfile_set_isize(sc, rts->rsumsize);
151 	if (error)
152 		return error;
153 
154 	/*
155 	 * Now exchange the contents.  Nothing in repair uses the temporary
156 	 * buffer, so we can reuse it for the tempfile exchrange information.
157 	 */
158 	error = xrep_tempexch_trans_reserve(sc, XFS_DATA_FORK, &rts->tempexch);
159 	if (error)
160 		return error;
161 
162 	error = xrep_tempexch_contents(sc, &rts->tempexch);
163 	if (error)
164 		return error;
165 
166 	/* Reset incore state and blow out the summary cache. */
167 	if (mp->m_rsum_cache)
168 		memset(mp->m_rsum_cache, 0xFF, mp->m_sb.sb_rbmblocks);
169 
170 	mp->m_rsumlevels = rts->rsumlevels;
171 	mp->m_rsumsize = rts->rsumsize;
172 
173 	/* Free the old rtsummary blocks if they're not in use. */
174 	return xrep_reap_ifork(sc, sc->tempip, XFS_DATA_FORK);
175 }
176