[PATCH 3/4] xfs: create refcount bag structure for btree repairs

Darrick J. Wong
2023-12-31T20:20:05Z

Create a bag structure for refcount information that uses the refcount
bag btree defined in the previous patch.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
---
fs/xfs/Makefile | 1
fs/xfs/scrub/rcbag.c | 331 ++++++++++++++++++++++++++++++++++++++++++++
fs/xfs/scrub/rcbag.h | 28 ++++
fs/xfs/scrub/rcbag_btree.c | 58 ++++++++
fs/xfs/scrub/rcbag_btree.h | 7 +
5 files changed, 425 insertions(+)
create mode 100644 fs/xfs/scrub/rcbag.c
create mode 100644 fs/xfs/scrub/rcbag.h

diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile
index f927a43cc16a5..a76e98e94b64a 100644
--- a/fs/xfs/Makefile
+++ b/fs/xfs/Makefile
@@ -199,6 +199,7 @@ xfs-y += $(addprefix scrub/, \
newbt.o \
nlinks_repair.o \
rcbag_btree.o \
+ rcbag.o \
reap.o \
refcount_repair.o \
repair.o \
diff --git a/fs/xfs/scrub/rcbag.c b/fs/xfs/scrub/rcbag.c
new file mode 100644
index 0000000000000..63f1b6e6488e1
--- /dev/null
+++ b/fs/xfs/scrub/rcbag.c
@@ -0,0 +1,331 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2022-2024 Oracle. All Rights Reserved.
+ * Author: Darrick J. Wong <djwong@kernel.org>
+ */
+#include "xfs.h"
+#include "xfs_fs.h"
+#include "xfs_shared.h"
+#include "xfs_format.h"
+#include "xfs_log_format.h"
+#include "xfs_trans.h"
+#include "xfs_trans_resv.h"
+#include "xfs_mount.h"
+#include "xfs_defer.h"
+#include "xfs_btree.h"
+#include "xfs_btree_mem.h"
+#include "xfs_error.h"
+#include "scrub/scrub.h"
+#include "scrub/xfile.h"
+#include "scrub/xfbtree.h"
+#include "scrub/rcbag_btree.h"
+#include "scrub/rcbag.h"
+#include "scrub/trace.h"
+
+struct rcbag {
+ struct xfs_mount *mp;
+ struct xfbtree *xfbtree;
+ uint64_t nr_items;
+};
+
+int
+rcbag_init(
+ struct xfs_mount *mp,
+ struct xfs_buftarg *target,
+ struct rcbag **bagp)
+{
+ struct rcbag *bag;
+ int error;
+
+ bag = kmalloc(sizeof(struct rcbag), XCHK_GFP_FLAGS);
+ if (!bag)
+ return -ENOMEM;
+
+ bag->nr_items = 0;
+ bag->mp = mp;
+
+ error = rcbagbt_mem_create(mp, target, &bag->xfbtree);
+ if (error)
+ goto out_bag;
+
+ *bagp = bag;
+ return 0;
+
+out_bag:
+ kfree(bag);
+ return error;
+}
+
+void
+rcbag_free(
+ struct rcbag **bagp)
+{
+ struct rcbag *bag = *bagp;
+
+ xfbtree_destroy(bag->xfbtree);
+ kfree(bag);
+ *bagp = NULL;
+}
+
+/* Track an rmap in the refcount bag. */
+int
+rcbag_add(
+ struct rcbag *bag,
+ struct xfs_trans *tp,
+ const struct xfs_rmap_irec *rmap)
+{
+ struct rcbag_rec bagrec;
+ struct xfs_mount *mp = bag->mp;
+ struct xfs_buf *head_bp;
+ struct xfs_btree_cur *cur;
+ int has;
+ int error;
+
+ error = xfbtree_head_read_buf(bag->xfbtree, tp, &head_bp);
+ if (error)
+ return error;
+
+ cur = rcbagbt_mem_cursor(mp, tp, head_bp, bag->xfbtree);
+ error = rcbagbt_lookup_eq(cur, rmap, &has);
+ if (error)
+ goto out_cur;
+
+ if (has) {
+ error = rcbagbt_get_rec(cur, &bagrec, &has);
+ if (error)
+ goto out_cur;
+ if (!has) {
+ error = -EFSCORRUPTED;
+ goto out_cur;
+ }
+
+ bagrec.rbg_refcount++;
+ error = rcbagbt_update(cur, &bagrec);
+ if (error)
+ goto out_cur;
+ } else {
+ bagrec.rbg_startblock = rmap->rm_startblock;
+ bagrec.rbg_blockcount = rmap->rm_blockcount;
+ bagrec.rbg_refcount = 1;
+
+ error = rcbagbt_insert(cur, &bagrec, &has);
+ if (error)
+ goto out_cur;
+ if (!has) {
+ error = -EFSCORRUPTED;
+ goto out_cur;
+ }
+ }
+
+ xfs_btree_del_cursor(cur, 0);
+ xfs_trans_brelse(tp, head_bp);
+
+ error = xfbtree_trans_commit(bag->xfbtree, tp);
+ if (error)
+ return error;
+
+ bag->nr_items++;
+ return 0;
+
+out_cur:
+ xfs_btree_del_cursor(cur, error);
+ xfs_trans_brelse(tp, head_bp);
+ xfbtree_trans_cancel(bag->xfbtree, tp);
+ return error;
+}
+
+uint64_t
+rcbag_count(
+ const struct rcbag *rcbag)
+{
+ return rcbag->nr_items;
+}
+
+#define BAGREC_NEXT(r) ((r)->rbg_startblock + (r)->rbg_blockcount)
+
+/*
+ * Find the next block where the refcount changes, given the next rmap we
+ * looked at and the ones we're already tracking.
+ */
+int
+rcbag_next_edge(
+ struct rcbag *bag,
+ struct xfs_trans *tp,
+ const struct xfs_rmap_irec *next_rmap,
+ bool next_valid,
+ uint32_t *next_bnop)
+{
+ struct rcbag_rec bagrec;
+ struct xfs_mount *mp = bag->mp;
+ struct xfs_buf *head_bp;
+ struct xfs_btree_cur *cur;
+ uint32_t next_bno = NULLAGBLOCK;
+ int has;
+ int error;
+
+ if (next_valid)
+ next_bno = next_rmap->rm_startblock;
+
+ error = xfbtree_head_read_buf(bag->xfbtree, tp, &head_bp);
+ if (error)
+ return error;
+
+ cur = rcbagbt_mem_cursor(mp, tp, head_bp, bag->xfbtree);
+ error = xfs_btree_goto_left_edge(cur);
+ if (error)
+ goto out_cur;
+
+ while (true) {
+ error = xfs_btree_increment(cur, 0, &has);
+ if (error)
+ goto out_cur;
+ if (!has)
+ break;
+
+ error = rcbagbt_get_rec(cur, &bagrec, &has);
+ if (error)
+ goto out_cur;
+ if (!has) {
+ error = -EFSCORRUPTED;
+ goto out_cur;
+ }
+
+ next_bno = min(next_bno, BAGREC_NEXT(&bagrec));
+ }
+
+ /*
+ * We should have found /something/ because either next_rrm is the next
+ * interesting rmap to look at after emitting this refcount extent, or
+ * there are other rmaps in rmap_bag contributing to the current
+ * sharing count. But if something is seriously wrong, bail out.
+ */
+ if (next_bno == NULLAGBLOCK) {
+ error = -EFSCORRUPTED;
+ goto out_cur;
+ }
+
+ xfs_btree_del_cursor(cur, 0);
+ xfs_trans_brelse(tp, head_bp);
+
+ *next_bnop = next_bno;
+ return 0;
+
+out_cur:
+ xfs_btree_del_cursor(cur, error);
+ xfs_trans_brelse(tp, head_bp);
+ return error;
+}
+
+/* Pop all refcount bag records that end at next_bno */
+int
+rcbag_remove_ending_at(
+ struct rcbag *bag,
+ struct xfs_trans *tp,
+ uint32_t next_bno)
+{
+ struct rcbag_rec bagrec;
+ struct xfs_mount *mp = bag->mp;
+ struct xfs_buf *head_bp;
+ struct xfs_btree_cur *cur;
+ int has;
+ int error;
+
+ error = xfbtree_head_read_buf(bag->xfbtree, tp, &head_bp);
+ if (error)
+ return error;
+
+ /* go to the right edge of the tree */
+ cur = rcbagbt_mem_cursor(mp, tp, head_bp, bag->xfbtree);
+ memset(&cur->bc_rec, 0xFF, sizeof(cur->bc_rec));
+ error = xfs_btree_lookup(cur, XFS_LOOKUP_GE, &has);
+ if (error)
+ goto out_cur;
+
+ while (true) {
+ error = xfs_btree_decrement(cur, 0, &has);
+ if (error)
+ goto out_cur;
+ if (!has)
+ break;
+
+ error = rcbagbt_get_rec(cur, &bagrec, &has);
+ if (error)
+ goto out_cur;
+ if (!has) {
+ error = -EFSCORRUPTED;
+ goto out_cur;
+ }
+
+ if (BAGREC_NEXT(&bagrec) != next_bno)
+ continue;
+
+ error = xfs_btree_delete(cur, &has);
+ if (error)
+ goto out_cur;
+ if (!has) {
+ error = -EFSCORRUPTED;
+ goto out_cur;
+ }
+
+ bag->nr_items -= bagrec.rbg_refcount;
+ }
+
+ xfs_btree_del_cursor(cur, 0);
+ xfs_trans_brelse(tp, head_bp);
+ return xfbtree_trans_commit(bag->xfbtree, tp);
+out_cur:
+ xfs_btree_del_cursor(cur, error);
+ xfs_trans_brelse(tp, head_bp);
+ xfbtree_trans_cancel(bag->xfbtree, tp);
+ return error;
+}
+
+/* Dump the rcbag. */
+void
+rcbag_dump(
+ struct rcbag *bag,
+ struct xfs_trans *tp)
+{
+ struct rcbag_rec bagrec;
+ struct xfs_mount *mp = bag->mp;
+ struct xfs_buf *head_bp;
+ struct xfs_btree_cur *cur;
+ unsigned long long nr = 0;
+ int has;
+ int error;
+
+ error = xfbtree_head_read_buf(bag->xfbtree, tp, &head_bp);
+ if (error)
+ return;
+
+ cur = rcbagbt_mem_cursor(mp, tp, head_bp, bag->xfbtree);
+ error = xfs_btree_goto_left_edge(cur);
+ if (error)
+ goto out_cur;
+
+ while (true) {
+ error = xfs_btree_increment(cur, 0, &has);
+ if (error)
+ goto out_cur;
+ if (!has)
+ break;
+
+ error = rcbagbt_get_rec(cur, &bagrec, &has);
+ if (error)
+ goto out_cur;
+ if (!has) {
+ error = -EFSCORRUPTED;
+ goto out_cur;
+ }
+
+ xfs_err(bag->mp, "[%llu]: bno 0x%x fsbcount 0x%x refcount 0x%llx\n",
+ nr++,
+ (unsigned int)bagrec.rbg_startblock,
+ (unsigned int)bagrec.rbg_blockcount,
+ (unsigned long long)bagrec.rbg_refcount);
+ }
+
+out_cur:
+ xfs_btree_del_cursor(cur, error);
+ xfs_trans_brelse(tp, head_bp);
+}
diff --git a/fs/xfs/scrub/rcbag.h b/fs/xfs/scrub/rcbag.h
new file mode 100644
index 0000000000000..08b6b85c09d6b
--- /dev/null
+++ b/fs/xfs/scrub/rcbag.h
@@ -0,0 +1,28 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2022-2024 Oracle. All Rights Reserved.
+ * Author: Darrick J. Wong <djwong@kernel.org>
+ */
+#ifndef __XFS_SCRUB_RCBAG_H__
+#define __XFS_SCRUB_RCBAG_H__
+
+struct xfs_mount;
+struct rcbag;
+struct xfs_buftarg;
+
+int rcbag_init(struct xfs_mount *mp, struct xfs_buftarg *target,
+ struct rcbag **bagp);
+void rcbag_free(struct rcbag **bagp);
+int rcbag_add(struct rcbag *bag, struct xfs_trans *tp,
+ const struct xfs_rmap_irec *rmap);
+uint64_t rcbag_count(const struct rcbag *bag);
+
+int rcbag_next_edge(struct rcbag *bag, struct xfs_trans *tp,
+ const struct xfs_rmap_irec *next_rmap, bool next_valid,
+ uint32_t *next_bnop);
+int rcbag_remove_ending_at(struct rcbag *bag, struct xfs_trans *tp,
+ uint32_t next_bno);
+
+void rcbag_dump(struct rcbag *bag, struct xfs_trans *tp);
+
+#endif /* __XFS_SCRUB_RCBAG_H__ */
diff --git a/fs/xfs/scrub/rcbag_btree.c b/fs/xfs/scrub/rcbag_btree.c
index 4b0c849321b25..3d66e80b7bc25 100644
--- a/fs/xfs/scrub/rcbag_btree.c
+++ b/fs/xfs/scrub/rcbag_btree.c
@@ -312,3 +312,61 @@ rcbagbt_destroy_cur_cache(void)
kmem_cache_destroy(rcbagbt_cur_cache);
rcbagbt_cur_cache = NULL;
}
+
+/* Look up the refcount bag record corresponding to this reverse mapping. */
+int
+rcbagbt_lookup_eq(
+ struct xfs_btree_cur *cur,
+ const struct xfs_rmap_irec *rmap,
+ int *success)
+{
+ struct rcbag_rec *rec = (struct rcbag_rec *)&cur->bc_rec;
+
+ rec->rbg_startblock = rmap->rm_startblock;
+ rec->rbg_blockcount = rmap->rm_blockcount;
+
+ return xfs_btree_lookup(cur, XFS_LOOKUP_EQ, success);
+}
+
+/* Get the data from the pointed-to record. */
+int
+rcbagbt_get_rec(
+ struct xfs_btree_cur *cur,
+ struct rcbag_rec *rec,
+ int *has)
+{
+ union xfs_btree_rec *btrec;
+ int error;
+
+ error = xfs_btree_get_rec(cur, &btrec, has);
+ if (error || !(*has))
+ return error;
+
+ memcpy(rec, btrec, sizeof(struct rcbag_rec));
+ return 0;
+}
+
+/* Update the record referred to by cur to the value given. */
+int
+rcbagbt_update(
+ struct xfs_btree_cur *cur,
+ const struct rcbag_rec *rec)
+{
+ union xfs_btree_rec btrec;
+
+ memcpy(&btrec, rec, sizeof(struct rcbag_rec));
+ return xfs_btree_update(cur, &btrec);
+}
+
+/* Update the record referred to by cur to the value given. */
+int
+rcbagbt_insert(
+ struct xfs_btree_cur *cur,
+ const struct rcbag_rec *rec,
+ int *success)
+{
+ struct rcbag_rec *btrec = (struct rcbag_rec *)&cur->bc_rec;
+
+ memcpy(btrec, rec, sizeof(struct rcbag_rec));
+ return xfs_btree_insert(cur, success);
+}
diff --git a/fs/xfs/scrub/rcbag_btree.h b/fs/xfs/scrub/rcbag_btree.h
index dfe276cfd96c1..6486b6ae53409 100644
--- a/fs/xfs/scrub/rcbag_btree.h
+++ b/fs/xfs/scrub/rcbag_btree.h
@@ -68,6 +68,13 @@ struct xfs_btree_cur *rcbagbt_mem_cursor(struct xfs_mount *mp,
int rcbagbt_mem_create(struct xfs_mount *mp, struct xfs_buftarg *target,
struct xfbtree **xfbtreep);

+int rcbagbt_lookup_eq(struct xfs_btree_cur *cur,
+ const struct xfs_rmap_irec *rmap, int *success);
+int rcbagbt_get_rec(struct xfs_btree_cur *cur, struct rcbag_rec *rec, int *has);
+int rcbagbt_update(struct xfs_btree_cur *cur, const struct rcbag_rec *rec);
+int rcbagbt_insert(struct xfs_btree_cur *cur, const struct rcbag_rec *rec,
+ int *success);
+
#else
# define rcbagbt_init_cur_cache() 0
# define rcbagbt_destroy_cur_cache() ((void)0)