[PATCH 38/43] xfs: capture realtime CoW staging extents when rebuilding rt rmapbt

Darrick J. Wong
2024-12-13T01:20:09Z

From: Darrick J. Wong <djwong@kernel.org>

Walk the realtime refcount btree to find the CoW staging extents when
we're rebuilding the realtime rmap btree.

Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
---
fs/xfs/scrub/repair.h | 1
fs/xfs/scrub/rgb_bitmap.h | 37 +++++++++++++++
fs/xfs/scrub/rtrmap_repair.c | 103 ++++++++++++++++++++++++++++++++++++++++++
3 files changed, 141 insertions(+)
create mode 100644 fs/xfs/scrub/rgb_bitmap.h

diff --git a/fs/xfs/scrub/repair.h b/fs/xfs/scrub/repair.h
index ac5962732d269d..77343813205375 100644
--- a/fs/xfs/scrub/repair.h
+++ b/fs/xfs/scrub/repair.h
@@ -50,6 +50,7 @@ xrep_trans_commit(

struct xbitmap;
struct xagb_bitmap;
+struct xrgb_bitmap;
struct xfsb_bitmap;

int xrep_fix_freelist(struct xfs_scrub *sc, int alloc_flags);
diff --git a/fs/xfs/scrub/rgb_bitmap.h b/fs/xfs/scrub/rgb_bitmap.h
new file mode 100644
index 00000000000000..47a5caf3a230d9
--- /dev/null
+++ b/fs/xfs/scrub/rgb_bitmap.h
@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2020-2024 Oracle. All Rights Reserved.
+ * Author: Darrick J. Wong <djwong@kernel.org>
+ */
+#ifndef __XFS_SCRUB_RGB_BITMAP_H__
+#define __XFS_SCRUB_RGB_BITMAP_H__
+
+/* Bitmaps, but for type-checked for xfs_rgblock_t */
+
+struct xrgb_bitmap {
+ struct xbitmap32 rgbitmap;
+};
+
+static inline void xrgb_bitmap_init(struct xrgb_bitmap *bitmap)
+{
+ xbitmap32_init(&bitmap->rgbitmap);
+}
+
+static inline void xrgb_bitmap_destroy(struct xrgb_bitmap *bitmap)
+{
+ xbitmap32_destroy(&bitmap->rgbitmap);
+}
+
+static inline int xrgb_bitmap_set(struct xrgb_bitmap *bitmap,
+ xfs_rgblock_t start, xfs_extlen_t len)
+{
+ return xbitmap32_set(&bitmap->rgbitmap, start, len);
+}
+
+static inline int xrgb_bitmap_walk(struct xrgb_bitmap *bitmap,
+ xbitmap32_walk_fn fn, void *priv)
+{
+ return xbitmap32_walk(&bitmap->rgbitmap, fn, priv);
+}
+
+#endif /* __XFS_SCRUB_RGB_BITMAP_H__ */
diff --git a/fs/xfs/scrub/rtrmap_repair.c b/fs/xfs/scrub/rtrmap_repair.c
index 49de8bc2dd17f5..f2fdd7a9fc2483 100644
--- a/fs/xfs/scrub/rtrmap_repair.c
+++ b/fs/xfs/scrub/rtrmap_repair.c
@@ -30,6 +30,7 @@
#include "xfs_rtalloc.h"
#include "xfs_ag.h"
#include "xfs_rtgroup.h"
+#include "xfs_refcount.h"
#include "scrub/xfs_scrub.h"
#include "scrub/scrub.h"
#include "scrub/common.h"
@@ -38,6 +39,7 @@
#include "scrub/repair.h"
#include "scrub/bitmap.h"
#include "scrub/fsb_bitmap.h"
+#include "scrub/rgb_bitmap.h"
#include "scrub/xfile.h"
#include "scrub/xfarray.h"
#include "scrub/iscan.h"
@@ -423,6 +425,100 @@ xrep_rtrmap_scan_ag(
return error;
}

+struct xrep_rtrmap_stash_run {
+ struct xrep_rtrmap *rr;
+ uint64_t owner;
+};
+
+static int
+xrep_rtrmap_stash_run(
+ uint32_t start,
+ uint32_t len,
+ void *priv)
+{
+ struct xrep_rtrmap_stash_run *rsr = priv;
+ struct xrep_rtrmap *rr = rsr->rr;
+ xfs_rgblock_t rgbno = start;
+
+ return xrep_rtrmap_stash(rr, rgbno, len, rsr->owner, 0, 0);
+}
+
+/*
+ * Emit rmaps for every extent of bits set in the bitmap. Caller must ensure
+ * that the ranges are in units of FS blocks.
+ */
+STATIC int
+xrep_rtrmap_stash_bitmap(
+ struct xrep_rtrmap *rr,
+ struct xrgb_bitmap *bitmap,
+ const struct xfs_owner_info *oinfo)
+{
+ struct xrep_rtrmap_stash_run rsr = {
+ .rr = rr,
+ .owner = oinfo->oi_owner,
+ };
+
+ return xrgb_bitmap_walk(bitmap, xrep_rtrmap_stash_run, &rsr);
+}
+
+/* Record a CoW staging extent. */
+STATIC int
+xrep_rtrmap_walk_cowblocks(
+ struct xfs_btree_cur *cur,
+ const struct xfs_refcount_irec *irec,
+ void *priv)
+{
+ struct xrgb_bitmap *bitmap = priv;
+
+ if (!xfs_refcount_check_domain(irec) ||
+ irec->rc_domain != XFS_REFC_DOMAIN_COW)
+ return -EFSCORRUPTED;
+
+ return xrgb_bitmap_set(bitmap, irec->rc_startblock,
+ irec->rc_blockcount);
+}
+
+/*
+ * Collect rmaps for the blocks containing the refcount btree, and all CoW
+ * staging extents.
+ */
+STATIC int
+xrep_rtrmap_find_refcount_rmaps(
+ struct xrep_rtrmap *rr)
+{
+ struct xrgb_bitmap cow_blocks; /* COWBIT */
+ struct xfs_refcount_irec low = {
+ .rc_startblock = 0,
+ .rc_domain = XFS_REFC_DOMAIN_COW,
+ };
+ struct xfs_refcount_irec high = {
+ .rc_startblock = -1U,
+ .rc_domain = XFS_REFC_DOMAIN_COW,
+ };
+ struct xfs_scrub *sc = rr->sc;
+ int error;
+
+ if (!xfs_has_rtreflink(sc->mp))
+ return 0;
+
+ xrgb_bitmap_init(&cow_blocks);
+
+ /* Collect rmaps for CoW staging extents. */
+ error = xfs_refcount_query_range(sc->sr.refc_cur, &low, &high,
+ xrep_rtrmap_walk_cowblocks, &cow_blocks);
+ if (error)
+ goto out_bitmap;
+
+ /* Generate rmaps for everything. */
+ error = xrep_rtrmap_stash_bitmap(rr, &cow_blocks, &XFS_RMAP_OINFO_COW);
+ if (error)
+ goto out_bitmap;
+
+out_bitmap:
+ xrgb_bitmap_destroy(&cow_blocks);
+ return error;
+}
+
/* Count and check all collected records. */
STATIC int
xrep_rtrmap_check_record(
@@ -460,6 +556,13 @@ xrep_rtrmap_find_rmaps(
return error;
}

+ /* Find CoW staging extents. */
+ xrep_rtgroup_btcur_init(sc, &sc->sr);
+ error = xrep_rtrmap_find_refcount_rmaps(rr);
+ xchk_rtgroup_btcur_free(&sc->sr);
+ if (error)
+ return error;
+
/*
* Set up for a potentially lengthy filesystem scan by reducing our
* transaction resource usage for the duration. Specifically: