1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * Copyright (C) 2017 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_rmap.h"
 14#include "xfs_refcount.h"
 15#include "scrub/scrub.h"
 16#include "scrub/common.h"
 17#include "scrub/btree.h"
 18
 19/*
 20 * Set us up to scrub reverse mapping btrees.
 21 */
 22int
 23xchk_setup_ag_rmapbt(
 24	struct xfs_scrub	*sc,
 25	struct xfs_inode	*ip)
 26{
 27	return xchk_setup_ag_btree(sc, ip, false);
 28}
 29
 30/* Reverse-mapping scrubber. */
 31
 32/* Cross-reference a rmap against the refcount btree. */
 33STATIC void
 34xchk_rmapbt_xref_refc(
 35	struct xfs_scrub	*sc,
 36	struct xfs_rmap_irec	*irec)
 37{
 38	xfs_agblock_t		fbno;
 39	xfs_extlen_t		flen;
 40	bool			non_inode;
 41	bool			is_bmbt;
 42	bool			is_attr;
 43	bool			is_unwritten;
 44	int			error;
 45
 46	if (!sc->sa.refc_cur || xchk_skip_xref(sc->sm))
 47		return;
 48
 49	non_inode = XFS_RMAP_NON_INODE_OWNER(irec->rm_owner);
 50	is_bmbt = irec->rm_flags & XFS_RMAP_BMBT_BLOCK;
 51	is_attr = irec->rm_flags & XFS_RMAP_ATTR_FORK;
 52	is_unwritten = irec->rm_flags & XFS_RMAP_UNWRITTEN;
 53
 54	/* If this is shared, must be a data fork extent. */
 55	error = xfs_refcount_find_shared(sc->sa.refc_cur, irec->rm_startblock,
 56			irec->rm_blockcount, &fbno, &flen, false);
 57	if (!xchk_should_check_xref(sc, &error, &sc->sa.refc_cur))
 58		return;
 59	if (flen != 0 && (non_inode || is_attr || is_bmbt || is_unwritten))
 60		xchk_btree_xref_set_corrupt(sc, sc->sa.refc_cur, 0);
 61}
 62
 63/* Cross-reference with the other btrees. */
 64STATIC void
 65xchk_rmapbt_xref(
 66	struct xfs_scrub	*sc,
 67	struct xfs_rmap_irec	*irec)
 68{
 69	xfs_agblock_t		agbno = irec->rm_startblock;
 70	xfs_extlen_t		len = irec->rm_blockcount;
 71
 72	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
 73		return;
 74
 75	xchk_xref_is_used_space(sc, agbno, len);
 76	if (irec->rm_owner == XFS_RMAP_OWN_INODES)
 77		xchk_xref_is_inode_chunk(sc, agbno, len);
 78	else
 79		xchk_xref_is_not_inode_chunk(sc, agbno, len);
 80	if (irec->rm_owner == XFS_RMAP_OWN_COW)
 81		xchk_xref_is_cow_staging(sc, irec->rm_startblock,
 82				irec->rm_blockcount);
 83	else
 84		xchk_rmapbt_xref_refc(sc, irec);
 85}
 86
 87/* Scrub an rmapbt record. */
 88STATIC int
 89xchk_rmapbt_rec(
 90	struct xchk_btree	*bs,
 91	union xfs_btree_rec	*rec)
 92{
 93	struct xfs_mount	*mp = bs->cur->bc_mp;
 94	struct xfs_rmap_irec	irec;
 95	xfs_agnumber_t		agno = bs->cur->bc_private.a.agno;
 96	bool			non_inode;
 97	bool			is_unwritten;
 98	bool			is_bmbt;
 99	bool			is_attr;
100	int			error;
101
102	error = xfs_rmap_btrec_to_irec(rec, &irec);
103	if (!xchk_btree_process_error(bs->sc, bs->cur, 0, &error))
104		goto out;
105
106	/* Check extent. */
107	if (irec.rm_startblock + irec.rm_blockcount <= irec.rm_startblock)
108		xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
109
110	if (irec.rm_owner == XFS_RMAP_OWN_FS) {
111		/*
112		 * xfs_verify_agbno returns false for static fs metadata.
113		 * Since that only exists at the start of the AG, validate
114		 * that by hand.
115		 */
116		if (irec.rm_startblock != 0 ||
117		    irec.rm_blockcount != XFS_AGFL_BLOCK(mp) + 1)
118			xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
119	} else {
120		/*
121		 * Otherwise we must point somewhere past the static metadata
122		 * but before the end of the FS.  Run the regular check.
123		 */
124		if (!xfs_verify_agbno(mp, agno, irec.rm_startblock) ||
125		    !xfs_verify_agbno(mp, agno, irec.rm_startblock +
126				irec.rm_blockcount - 1))
127			xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
128	}
129
130	/* Check flags. */
131	non_inode = XFS_RMAP_NON_INODE_OWNER(irec.rm_owner);
132	is_bmbt = irec.rm_flags & XFS_RMAP_BMBT_BLOCK;
133	is_attr = irec.rm_flags & XFS_RMAP_ATTR_FORK;
134	is_unwritten = irec.rm_flags & XFS_RMAP_UNWRITTEN;
135
136	if (is_bmbt && irec.rm_offset != 0)
137		xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
138
139	if (non_inode && irec.rm_offset != 0)
140		xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
141
142	if (is_unwritten && (is_bmbt || non_inode || is_attr))
143		xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
144
145	if (non_inode && (is_bmbt || is_unwritten || is_attr))
146		xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
147
148	if (!non_inode) {
149		if (!xfs_verify_ino(mp, irec.rm_owner))
150			xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
151	} else {
152		/* Non-inode owner within the magic values? */
153		if (irec.rm_owner <= XFS_RMAP_OWN_MIN ||
154		    irec.rm_owner > XFS_RMAP_OWN_FS)
155			xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
156	}
157
158	xchk_rmapbt_xref(bs->sc, &irec);
159out:
160	return error;
161}
162
163/* Scrub the rmap btree for some AG. */
164int
165xchk_rmapbt(
166	struct xfs_scrub	*sc)
167{
168	return xchk_btree(sc, sc->sa.rmap_cur, xchk_rmapbt_rec,
169			&XFS_RMAP_OINFO_AG, NULL);
170}
171
172/* xref check that the extent is owned by a given owner */
173static inline void
174xchk_xref_check_owner(
175	struct xfs_scrub		*sc,
176	xfs_agblock_t			bno,
177	xfs_extlen_t			len,
178	const struct xfs_owner_info	*oinfo,
179	bool				should_have_rmap)
180{
181	bool				has_rmap;
182	int				error;
183
184	if (!sc->sa.rmap_cur || xchk_skip_xref(sc->sm))
185		return;
186
187	error = xfs_rmap_record_exists(sc->sa.rmap_cur, bno, len, oinfo,
188			&has_rmap);
189	if (!xchk_should_check_xref(sc, &error, &sc->sa.rmap_cur))
190		return;
191	if (has_rmap != should_have_rmap)
192		xchk_btree_xref_set_corrupt(sc, sc->sa.rmap_cur, 0);
193}
194
195/* xref check that the extent is owned by a given owner */
196void
197xchk_xref_is_owned_by(
198	struct xfs_scrub		*sc,
199	xfs_agblock_t			bno,
200	xfs_extlen_t			len,
201	const struct xfs_owner_info	*oinfo)
202{
203	xchk_xref_check_owner(sc, bno, len, oinfo, true);
204}
205
206/* xref check that the extent is not owned by a given owner */
207void
208xchk_xref_is_not_owned_by(
209	struct xfs_scrub		*sc,
210	xfs_agblock_t			bno,
211	xfs_extlen_t			len,
212	const struct xfs_owner_info	*oinfo)
213{
214	xchk_xref_check_owner(sc, bno, len, oinfo, false);
215}
216
217/* xref check that the extent has no reverse mapping at all */
218void
219xchk_xref_has_no_owner(
220	struct xfs_scrub	*sc,
221	xfs_agblock_t		bno,
222	xfs_extlen_t		len)
223{
224	bool			has_rmap;
225	int			error;
226
227	if (!sc->sa.rmap_cur || xchk_skip_xref(sc->sm))
228		return;
229
230	error = xfs_rmap_has_record(sc->sa.rmap_cur, bno, len, &has_rmap);
231	if (!xchk_should_check_xref(sc, &error, &sc->sa.rmap_cur))
232		return;
233	if (has_rmap)
234		xchk_btree_xref_set_corrupt(sc, sc->sa.rmap_cur, 0);
235}