rtrmap.c

  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Copyright (c) 2018-2024 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_defer.h"
 13#include "xfs_btree.h"
 14#include "xfs_bit.h"
 15#include "xfs_log_format.h"
 16#include "xfs_trans.h"
 17#include "xfs_sb.h"
 18#include "xfs_rmap.h"
 19#include "xfs_rmap_btree.h"
 20#include "xfs_rtrmap_btree.h"
 21#include "xfs_inode.h"
 22#include "xfs_rtalloc.h"
 23#include "xfs_rtgroup.h"
 24#include "xfs_metafile.h"
 25#include "xfs_refcount.h"
 26#include "scrub/xfs_scrub.h"
 27#include "scrub/scrub.h"
 28#include "scrub/common.h"
 29#include "scrub/btree.h"
 30#include "scrub/trace.h"
 31#include "scrub/repair.h"
 32
 33/* Set us up with the realtime metadata locked. */
 34int
 35xchk_setup_rtrmapbt(
 36	struct xfs_scrub	*sc)
 37{
 38	int			error;
 39
 40	if (xchk_need_intent_drain(sc))
 41		xchk_fsgates_enable(sc, XCHK_FSGATES_DRAIN);
 42
 43	if (xchk_could_repair(sc)) {
 44		error = xrep_setup_rtrmapbt(sc);
 45		if (error)
 46			return error;
 47	}
 48
 49	error = xchk_rtgroup_init(sc, sc->sm->sm_agno, &sc->sr);
 50	if (error)
 51		return error;
 52
 53	error = xchk_setup_rt(sc);
 54	if (error)
 55		return error;
 56
 57	error = xchk_install_live_inode(sc, rtg_rmap(sc->sr.rtg));
 58	if (error)
 59		return error;
 60
 61	return xchk_rtgroup_lock(sc, &sc->sr, XCHK_RTGLOCK_ALL);
 62}
 63
 64/* Realtime reverse mapping. */
 65
 66struct xchk_rtrmap {
 67	/*
 68	 * The furthest-reaching of the rmapbt records that we've already
 69	 * processed.  This enables us to detect overlapping records for space
 70	 * allocations that cannot be shared.
 71	 */
 72	struct xfs_rmap_irec	overlap_rec;
 73
 74	/*
 75	 * The previous rmapbt record, so that we can check for two records
 76	 * that could be one.
 77	 */
 78	struct xfs_rmap_irec	prev_rec;
 79};
 80
 81static inline bool
 82xchk_rtrmapbt_is_shareable(
 83	struct xfs_scrub		*sc,
 84	const struct xfs_rmap_irec	*irec)
 85{
 86	if (!xfs_has_rtreflink(sc->mp))
 87		return false;
 88	if (irec->rm_flags & XFS_RMAP_UNWRITTEN)
 89		return false;
 90	return true;
 91}
 92
 93/* Flag failures for records that overlap but cannot. */
 94STATIC void
 95xchk_rtrmapbt_check_overlapping(
 96	struct xchk_btree		*bs,
 97	struct xchk_rtrmap		*cr,
 98	const struct xfs_rmap_irec	*irec)
 99{
100	xfs_rtblock_t			pnext, inext;
101
102	if (bs->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
103		return;
104
105	/* No previous record? */
106	if (cr->overlap_rec.rm_blockcount == 0)
107		goto set_prev;
108
109	/* Do overlap_rec and irec overlap? */
110	pnext = cr->overlap_rec.rm_startblock + cr->overlap_rec.rm_blockcount;
111	if (pnext <= irec->rm_startblock)
112		goto set_prev;
113
114	/* Overlap is only allowed if both records are data fork mappings. */
115	if (!xchk_rtrmapbt_is_shareable(bs->sc, &cr->overlap_rec) ||
116	    !xchk_rtrmapbt_is_shareable(bs->sc, irec))
117		xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
118
119	/* Save whichever rmap record extends furthest. */
120	inext = irec->rm_startblock + irec->rm_blockcount;
121	if (pnext > inext)
122		return;
123
124set_prev:
125	memcpy(&cr->overlap_rec, irec, sizeof(struct xfs_rmap_irec));
126}
127
128/* Decide if two reverse-mapping records can be merged. */
129static inline bool
130xchk_rtrmap_mergeable(
131	struct xchk_rtrmap		*cr,
132	const struct xfs_rmap_irec	*r2)
133{
134	const struct xfs_rmap_irec	*r1 = &cr->prev_rec;
135
136	/* Ignore if prev_rec is not yet initialized. */
137	if (cr->prev_rec.rm_blockcount == 0)
138		return false;
139
140	if (r1->rm_owner != r2->rm_owner)
141		return false;
142	if (r1->rm_startblock + r1->rm_blockcount != r2->rm_startblock)
143		return false;
144	if ((unsigned long long)r1->rm_blockcount + r2->rm_blockcount >
145	    XFS_RMAP_LEN_MAX)
146		return false;
147	if (r1->rm_flags != r2->rm_flags)
148		return false;
149	return r1->rm_offset + r1->rm_blockcount == r2->rm_offset;
150}
151
152/* Flag failures for records that could be merged. */
153STATIC void
154xchk_rtrmapbt_check_mergeable(
155	struct xchk_btree		*bs,
156	struct xchk_rtrmap		*cr,
157	const struct xfs_rmap_irec	*irec)
158{
159	if (bs->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
160		return;
161
162	if (xchk_rtrmap_mergeable(cr, irec))
163		xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
164
165	memcpy(&cr->prev_rec, irec, sizeof(struct xfs_rmap_irec));
166}
167
168/* Cross-reference a rmap against the refcount btree. */
169STATIC void
170xchk_rtrmapbt_xref_rtrefc(
171	struct xfs_scrub	*sc,
172	struct xfs_rmap_irec	*irec)
173{
174	xfs_rgblock_t		fbno;
175	xfs_extlen_t		flen;
176	bool			is_inode;
177	bool			is_bmbt;
178	bool			is_attr;
179	bool			is_unwritten;
180	int			error;
181
182	if (!sc->sr.refc_cur || xchk_skip_xref(sc->sm))
183		return;
184
185	is_inode = !XFS_RMAP_NON_INODE_OWNER(irec->rm_owner);
186	is_bmbt = irec->rm_flags & XFS_RMAP_BMBT_BLOCK;
187	is_attr = irec->rm_flags & XFS_RMAP_ATTR_FORK;
188	is_unwritten = irec->rm_flags & XFS_RMAP_UNWRITTEN;
189
190	/* If this is shared, must be a data fork extent. */
191	error = xfs_refcount_find_shared(sc->sr.refc_cur, irec->rm_startblock,
192			irec->rm_blockcount, &fbno, &flen, false);
193	if (!xchk_should_check_xref(sc, &error, &sc->sr.refc_cur))
194		return;
195	if (flen != 0 && (!is_inode || is_attr || is_bmbt || is_unwritten))
196		xchk_btree_xref_set_corrupt(sc, sc->sr.refc_cur, 0);
197}
198
199/* Cross-reference with other metadata. */
200STATIC void
201xchk_rtrmapbt_xref(
202	struct xfs_scrub	*sc,
203	struct xfs_rmap_irec	*irec)
204{
205	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
206		return;
207
208	xchk_xref_is_used_rt_space(sc,
209			xfs_rgbno_to_rtb(sc->sr.rtg, irec->rm_startblock),
210			irec->rm_blockcount);
211	if (irec->rm_owner == XFS_RMAP_OWN_COW)
212		xchk_xref_is_cow_staging(sc, irec->rm_startblock,
213				irec->rm_blockcount);
214	else
215		xchk_rtrmapbt_xref_rtrefc(sc, irec);
216}
217
218/* Scrub a realtime rmapbt record. */
219STATIC int
220xchk_rtrmapbt_rec(
221	struct xchk_btree		*bs,
222	const union xfs_btree_rec	*rec)
223{
224	struct xchk_rtrmap		*cr = bs->private;
225	struct xfs_rmap_irec		irec;
226
227	if (xfs_rmap_btrec_to_irec(rec, &irec) != NULL ||
228	    xfs_rtrmap_check_irec(to_rtg(bs->cur->bc_group), &irec) != NULL) {
229		xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
230		return 0;
231	}
232
233	if (bs->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
234		return 0;
235
236	xchk_rtrmapbt_check_mergeable(bs, cr, &irec);
237	xchk_rtrmapbt_check_overlapping(bs, cr, &irec);
238	xchk_rtrmapbt_xref(bs->sc, &irec);
239	return 0;
240}
241
242/* Scrub the realtime rmap btree. */
243int
244xchk_rtrmapbt(
245	struct xfs_scrub	*sc)
246{
247	struct xfs_inode	*ip = rtg_rmap(sc->sr.rtg);
248	struct xfs_owner_info	oinfo;
249	struct xchk_rtrmap	cr = { };
250	int			error;
251
252	error = xchk_metadata_inode_forks(sc);
253	if (error || (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT))
254		return error;
255
256	xfs_rmap_ino_bmbt_owner(&oinfo, ip->i_ino, XFS_DATA_FORK);
257	return xchk_btree(sc, sc->sr.rmap_cur, xchk_rtrmapbt_rec, &oinfo, &cr);
258}
259
260/* xref check that the extent has no realtime reverse mapping at all */
261void
262xchk_xref_has_no_rt_owner(
263	struct xfs_scrub	*sc,
264	xfs_rgblock_t		bno,
265	xfs_extlen_t		len)
266{
267	enum xbtree_recpacking	outcome;
268	int			error;
269
270	if (!sc->sr.rmap_cur || xchk_skip_xref(sc->sm))
271		return;
272
273	error = xfs_rmap_has_records(sc->sr.rmap_cur, bno, len, &outcome);
274	if (!xchk_should_check_xref(sc, &error, &sc->sr.rmap_cur))
275		return;
276	if (outcome != XBTREE_RECPACKING_EMPTY)
277		xchk_btree_xref_set_corrupt(sc, sc->sr.rmap_cur, 0);
278}
279
280/* xref check that the extent is completely mapped */
281void
282xchk_xref_has_rt_owner(
283	struct xfs_scrub	*sc,
284	xfs_rgblock_t		bno,
285	xfs_extlen_t		len)
286{
287	enum xbtree_recpacking	outcome;
288	int			error;
289
290	if (!sc->sr.rmap_cur || xchk_skip_xref(sc->sm))
291		return;
292
293	error = xfs_rmap_has_records(sc->sr.rmap_cur, bno, len, &outcome);
294	if (!xchk_should_check_xref(sc, &error, &sc->sr.rmap_cur))
295		return;
296	if (outcome != XBTREE_RECPACKING_FULL)
297		xchk_btree_xref_set_corrupt(sc, sc->sr.rmap_cur, 0);
298}
299
300/* xref check that the extent is only owned by a given owner */
301void
302xchk_xref_is_only_rt_owned_by(
303	struct xfs_scrub		*sc,
304	xfs_agblock_t			bno,
305	xfs_extlen_t			len,
306	const struct xfs_owner_info	*oinfo)
307{
308	struct xfs_rmap_matches		res;
309	int				error;
310
311	if (!sc->sr.rmap_cur || xchk_skip_xref(sc->sm))
312		return;
313
314	error = xfs_rmap_count_owners(sc->sr.rmap_cur, bno, len, oinfo, &res);
315	if (!xchk_should_check_xref(sc, &error, &sc->sr.rmap_cur))
316		return;
317	if (res.matches != 1)
318		xchk_btree_xref_set_corrupt(sc, sc->sr.rmap_cur, 0);
319	if (res.bad_non_owner_matches)
320		xchk_btree_xref_set_corrupt(sc, sc->sr.rmap_cur, 0);
321	if (res.non_owner_matches)
322		xchk_btree_xref_set_corrupt(sc, sc->sr.rmap_cur, 0);
323}