1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2020-2023 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_inode.h"
16#include "xfs_bit.h"
17#include "xfs_bmap.h"
18#include "xfs_bmap_btree.h"
19#include "scrub/scrub.h"
20#include "scrub/common.h"
21#include "scrub/trace.h"
22#include "scrub/repair.h"
23#include "scrub/xfile.h"
24#include "scrub/rtbitmap.h"
25
26/* Set up to repair the realtime bitmap file metadata. */
27int
28xrep_setup_rtbitmap(
29	struct xfs_scrub	*sc,
30	struct xchk_rtbitmap	*rtb)
31{
32	struct xfs_mount	*mp = sc->mp;
33	unsigned long long	blocks = 0;
34
35	/*
36	 * Reserve enough blocks to write out a completely new bmbt for a
37	 * maximally fragmented bitmap file.  We do not hold the rtbitmap
38	 * ILOCK yet, so this is entirely speculative.
39	 */
40	blocks = xfs_bmbt_calc_size(mp, mp->m_sb.sb_rbmblocks);
41	if (blocks > UINT_MAX)
42		return -EOPNOTSUPP;
43
44	rtb->resblks += blocks;
45	return 0;
46}
47
48/*
49 * Make sure that the given range of the data fork of the realtime file is
50 * mapped to written blocks.  The caller must ensure that the inode is joined
51 * to the transaction.
52 */
53STATIC int
54xrep_rtbitmap_data_mappings(
55	struct xfs_scrub	*sc,
56	xfs_filblks_t		len)
57{
58	struct xfs_bmbt_irec	map;
59	xfs_fileoff_t		off = 0;
60	int			error;
61
62	ASSERT(sc->ip != NULL);
63
64	while (off < len) {
65		int		nmaps = 1;
66
67		/*
68		 * If we have a real extent mapping this block then we're
69		 * in ok shape.
70		 */
71		error = xfs_bmapi_read(sc->ip, off, len - off, &map, &nmaps,
72				XFS_DATA_FORK);
73		if (error)
74			return error;
75		if (nmaps == 0) {
76			ASSERT(nmaps != 0);
77			return -EFSCORRUPTED;
78		}
79
80		/*
81		 * Written extents are ok.  Holes are not filled because we
82		 * do not know the freespace information.
83		 */
84		if (xfs_bmap_is_written_extent(&map) ||
85		    map.br_startblock == HOLESTARTBLOCK) {
86			off = map.br_startoff + map.br_blockcount;
87			continue;
88		}
89
90		/*
91		 * If we find a delalloc reservation then something is very
92		 * very wrong.  Bail out.
93		 */
94		if (map.br_startblock == DELAYSTARTBLOCK)
95			return -EFSCORRUPTED;
96
97		/* Make sure we're really converting an unwritten extent. */
98		if (map.br_state != XFS_EXT_UNWRITTEN) {
99			ASSERT(map.br_state == XFS_EXT_UNWRITTEN);
100			return -EFSCORRUPTED;
101		}
102
103		/* Make sure this block has a real zeroed extent mapped. */
104		nmaps = 1;
105		error = xfs_bmapi_write(sc->tp, sc->ip, map.br_startoff,
106				map.br_blockcount,
107				XFS_BMAPI_CONVERT | XFS_BMAPI_ZERO,
108				0, &map, &nmaps);
109		if (error)
110			return error;
111
112		/* Commit new extent and all deferred work. */
113		error = xrep_defer_finish(sc);
114		if (error)
115			return error;
116
117		off = map.br_startoff + map.br_blockcount;
118	}
119
120	return 0;
121}
122
123/* Fix broken rt volume geometry. */
124STATIC int
125xrep_rtbitmap_geometry(
126	struct xfs_scrub	*sc,
127	struct xchk_rtbitmap	*rtb)
128{
129	struct xfs_mount	*mp = sc->mp;
130	struct xfs_trans	*tp = sc->tp;
131
132	/* Superblock fields */
133	if (mp->m_sb.sb_rextents != rtb->rextents)
134		xfs_trans_mod_sb(sc->tp, XFS_TRANS_SB_REXTENTS,
135				rtb->rextents - mp->m_sb.sb_rextents);
136
137	if (mp->m_sb.sb_rbmblocks != rtb->rbmblocks)
138		xfs_trans_mod_sb(tp, XFS_TRANS_SB_RBMBLOCKS,
139				rtb->rbmblocks - mp->m_sb.sb_rbmblocks);
140
141	if (mp->m_sb.sb_rextslog != rtb->rextslog)
142		xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTSLOG,
143				rtb->rextslog - mp->m_sb.sb_rextslog);
144
145	/* Fix broken isize */
146	sc->ip->i_disk_size = roundup_64(sc->ip->i_disk_size,
147					 mp->m_sb.sb_blocksize);
148
149	if (sc->ip->i_disk_size < XFS_FSB_TO_B(mp, rtb->rbmblocks))
150		sc->ip->i_disk_size = XFS_FSB_TO_B(mp, rtb->rbmblocks);
151
152	xfs_trans_log_inode(sc->tp, sc->ip, XFS_ILOG_CORE);
153	return xrep_roll_trans(sc);
154}
155
156/* Repair the realtime bitmap file metadata. */
157int
158xrep_rtbitmap(
159	struct xfs_scrub	*sc)
160{
161	struct xchk_rtbitmap	*rtb = sc->buf;
162	struct xfs_mount	*mp = sc->mp;
163	unsigned long long	blocks = 0;
164	int			error;
165
166	/* Impossibly large rtbitmap means we can't touch the filesystem. */
167	if (rtb->rbmblocks > U32_MAX)
168		return 0;
169
170	/*
171	 * If the size of the rt bitmap file is larger than what we reserved,
172	 * figure out if we need to adjust the block reservation in the
173	 * transaction.
174	 */
175	blocks = xfs_bmbt_calc_size(mp, rtb->rbmblocks);
176	if (blocks > UINT_MAX)
177		return -EOPNOTSUPP;
178	if (blocks > rtb->resblks) {
179		error = xfs_trans_reserve_more(sc->tp, blocks, 0);
180		if (error)
181			return error;
182
183		rtb->resblks += blocks;
184	}
185
186	/* Fix inode core and forks. */
187	error = xrep_metadata_inode_forks(sc);
188	if (error)
189		return error;
190
191	xfs_trans_ijoin(sc->tp, sc->ip, 0);
192
193	/* Ensure no unwritten extents. */
194	error = xrep_rtbitmap_data_mappings(sc, rtb->rbmblocks);
195	if (error)
196		return error;
197
198	/* Fix inconsistent bitmap geometry */
199	return xrep_rtbitmap_geometry(sc, rtb);
200}
201