bcachefs: Split out recovery_passes.c

We've grown a fair amount of code for managing recovery passes; tracking
which ones we're running, which ones need to be run, and flagging in the
superblock which ones need to be run on the next recovery.

So it's worth splitting out into its own file, this code is pretty
different from the code in recovery.c.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/Makefile

@@ -67,6 +67,7 @@ bcachefs-y		:=	\
 	quota.o			\
 	rebalance.o		\
 	recovery.o		\
+	recovery_passes.o	\
 	reflink.o		\
 	replicas.o		\
 	sb-clean.o		\

fs/bcachefs/bcachefs.h

@@ -209,7 +209,7 @@
 #include "fifo.h"
 #include "nocow_locking_types.h"
 #include "opts.h"
-#include "recovery_types.h"
+#include "recovery_passes_types.h"
 #include "sb-errors_types.h"
 #include "seqmutex.h"
 #include "time_stats.h"

fs/bcachefs/btree_gc.c

@@ -25,7 +25,7 @@
 #include "journal.h"
 #include "keylist.h"
 #include "move.h"
-#include "recovery.h"
+#include "recovery_passes.h"
 #include "reflink.h"
 #include "replicas.h"
 #include "super-io.h"

fs/bcachefs/btree_update_interior.c

@@ -19,7 +19,7 @@
 #include "journal.h"
 #include "journal_reclaim.h"
 #include "keylist.h"
-#include "recovery.h"
+#include "recovery_passes.h"
 #include "replicas.h"
 #include "super-io.h"
 #include "trace.h"

fs/bcachefs/chardev.c

@@ -7,7 +7,7 @@
 #include "chardev.h"
 #include "journal.h"
 #include "move.h"
-#include "recovery.h"
+#include "recovery_passes.h"
 #include "replicas.h"
 #include "super.h"
 #include "super-io.h"

fs/bcachefs/error.c

 // SPDX-License-Identifier: GPL-2.0
 #include "bcachefs.h"
 #include "error.h"
-#include "recovery.h"
+#include "recovery_passes.h"
 #include "super.h"
 #include "thread_with_file.h"
 

fs/bcachefs/fsck.c

@@ -12,7 +12,7 @@
 #include "fsck.h"
 #include "inode.h"
 #include "keylist.h"
-#include "recovery.h"
+#include "recovery_passes.h"
 #include "snapshot.h"
 #include "super.h"
 #include "xattr.h"

fs/bcachefs/recovery.c

 // SPDX-License-Identifier: GPL-2.0
 
 #include "bcachefs.h"
-#include "backpointers.h"
-#include "bkey_buf.h"
 #include "alloc_background.h"
-#include "btree_gc.h"
+#include "bkey_buf.h"
 #include "btree_journal_iter.h"
 #include "btree_update.h"
 #include "btree_update_interior.h"
 #include "btree_io.h"
 #include "buckets.h"
 #include "dirent.h"
-#include "ec.h"
 #include "errcode.h"
 #include "error.h"
 #include "fs-common.h"
-#include "fsck.h"
 #include "journal_io.h"
 #include "journal_reclaim.h"
 #include "journal_seq_blacklist.h"
-#include "lru.h"
 #include "logged_ops.h"
 #include "move.h"
 #include "quota.h"
 #include "rebalance.h"
 #include "recovery.h"
+#include "recovery_passes.h"
 #include "replicas.h"
 #include "sb-clean.h"
 #include "sb-downgrade.h"
 #include "snapshot.h"
-#include "subvolume.h"
 #include "super-io.h"
 
 #include <linux/sort.h>
@@ -186,7 +181,7 @@ static int journal_sort_seq_cmp(const void *_l, const void *_r)
 	return cmp_int(l->journal_seq, r->journal_seq);
 }
 
-static int bch2_journal_replay(struct bch_fs *c)
+int bch2_journal_replay(struct bch_fs *c)
 {
 	struct journal_keys *keys = &c->journal_keys;
 	DARRAY(struct journal_key *) keys_sorted = { 0 };
@@ -471,150 +466,6 @@ static int read_btree_roots(struct bch_fs *c)
 	return ret;
 }
 
-static int bch2_initialize_subvolumes(struct bch_fs *c)
-{
-	struct bkey_i_snapshot_tree	root_tree;
-	struct bkey_i_snapshot		root_snapshot;
-	struct bkey_i_subvolume		root_volume;
-	int ret;
-
-	bkey_snapshot_tree_init(&root_tree.k_i);
-	root_tree.k.p.offset		= 1;
-	root_tree.v.master_subvol	= cpu_to_le32(1);
-	root_tree.v.root_snapshot	= cpu_to_le32(U32_MAX);
-
-	bkey_snapshot_init(&root_snapshot.k_i);
-	root_snapshot.k.p.offset = U32_MAX;
-	root_snapshot.v.flags	= 0;
-	root_snapshot.v.parent	= 0;
-	root_snapshot.v.subvol	= cpu_to_le32(BCACHEFS_ROOT_SUBVOL);
-	root_snapshot.v.tree	= cpu_to_le32(1);
-	SET_BCH_SNAPSHOT_SUBVOL(&root_snapshot.v, true);
-
-	bkey_subvolume_init(&root_volume.k_i);
-	root_volume.k.p.offset = BCACHEFS_ROOT_SUBVOL;
-	root_volume.v.flags	= 0;
-	root_volume.v.snapshot	= cpu_to_le32(U32_MAX);
-	root_volume.v.inode	= cpu_to_le64(BCACHEFS_ROOT_INO);
-
-	ret =   bch2_btree_insert(c, BTREE_ID_snapshot_trees,	&root_tree.k_i, NULL, 0) ?:
-		bch2_btree_insert(c, BTREE_ID_snapshots,	&root_snapshot.k_i, NULL, 0) ?:
-		bch2_btree_insert(c, BTREE_ID_subvolumes,	&root_volume.k_i, NULL, 0);
-	bch_err_fn(c, ret);
-	return ret;
-}
-
-static int __bch2_fs_upgrade_for_subvolumes(struct btree_trans *trans)
-{
-	struct btree_iter iter;
-	struct bkey_s_c k;
-	struct bch_inode_unpacked inode;
-	int ret;
-
-	k = bch2_bkey_get_iter(trans, &iter, BTREE_ID_inodes,
-			       SPOS(0, BCACHEFS_ROOT_INO, U32_MAX), 0);
-	ret = bkey_err(k);
-	if (ret)
-		return ret;
-
-	if (!bkey_is_inode(k.k)) {
-		bch_err(trans->c, "root inode not found");
-		ret = -BCH_ERR_ENOENT_inode;
-		goto err;
-	}
-
-	ret = bch2_inode_unpack(k, &inode);
-	BUG_ON(ret);
-
-	inode.bi_subvol = BCACHEFS_ROOT_SUBVOL;
-
-	ret = bch2_inode_write(trans, &iter, &inode);
-err:
-	bch2_trans_iter_exit(trans, &iter);
-	return ret;
-}
-
-/* set bi_subvol on root inode */
-noinline_for_stack
-static int bch2_fs_upgrade_for_subvolumes(struct bch_fs *c)
-{
-	int ret = bch2_trans_do(c, NULL, NULL, BCH_TRANS_COMMIT_lazy_rw,
-				__bch2_fs_upgrade_for_subvolumes(trans));
-	bch_err_fn(c, ret);
-	return ret;
-}
-
-const char * const bch2_recovery_passes[] = {
-#define x(_fn, ...)	#_fn,
-	BCH_RECOVERY_PASSES()
-#undef x
-	NULL
-};
-
-static int bch2_check_allocations(struct bch_fs *c)
-{
-	return bch2_gc(c, true, c->opts.norecovery);
-}
-
-static int bch2_set_may_go_rw(struct bch_fs *c)
-{
-	struct journal_keys *keys = &c->journal_keys;
-
-	/*
-	 * After we go RW, the journal keys buffer can't be modified (except for
-	 * setting journal_key->overwritten: it will be accessed by multiple
-	 * threads
-	 */
-	move_gap(keys, keys->nr);
-
-	set_bit(BCH_FS_may_go_rw, &c->flags);
-
-	if (keys->nr || c->opts.fsck || !c->sb.clean)
-		return bch2_fs_read_write_early(c);
-	return 0;
-}
-
-struct recovery_pass_fn {
-	int		(*fn)(struct bch_fs *);
-	unsigned	when;
-};
-
-static struct recovery_pass_fn recovery_pass_fns[] = {
-#define x(_fn, _id, _when)	{ .fn = bch2_##_fn, .when = _when },
-	BCH_RECOVERY_PASSES()
-#undef x
-};
-
-u64 bch2_recovery_passes_to_stable(u64 v)
-{
-	static const u8 map[] = {
-#define x(n, id, ...)	[BCH_RECOVERY_PASS_##n] = BCH_RECOVERY_PASS_STABLE_##n,
-	BCH_RECOVERY_PASSES()
-#undef x
-	};
-
-	u64 ret = 0;
-	for (unsigned i = 0; i < ARRAY_SIZE(map); i++)
-		if (v & BIT_ULL(i))
-			ret |= BIT_ULL(map[i]);
-	return ret;
-}
-
-u64 bch2_recovery_passes_from_stable(u64 v)
-{
-	static const u8 map[] = {
-#define x(n, id, ...)	[BCH_RECOVERY_PASS_STABLE_##n] = BCH_RECOVERY_PASS_##n,
-	BCH_RECOVERY_PASSES()
-#undef x
-	};
-
-	u64 ret = 0;
-	for (unsigned i = 0; i < ARRAY_SIZE(map); i++)
-		if (v & BIT_ULL(i))
-			ret |= BIT_ULL(map[i]);
-	return ret;
-}
-
 static bool check_version_upgrade(struct bch_fs *c)
 {
 	unsigned latest_version	= bcachefs_metadata_version_current;
@@ -687,96 +538,6 @@ static bool check_version_upgrade(struct bch_fs *c)
 	return false;
 }
 
-u64 bch2_fsck_recovery_passes(void)
-{
-	u64 ret = 0;
-
-	for (unsigned i = 0; i < ARRAY_SIZE(recovery_pass_fns); i++)
-		if (recovery_pass_fns[i].when & PASS_FSCK)
-			ret |= BIT_ULL(i);
-	return ret;
-}
-
-static bool should_run_recovery_pass(struct bch_fs *c, enum bch_recovery_pass pass)
-{
-	struct recovery_pass_fn *p = recovery_pass_fns + pass;
-
-	if (c->opts.norecovery && pass > BCH_RECOVERY_PASS_snapshots_read)
-		return false;
-	if (c->recovery_passes_explicit & BIT_ULL(pass))
-		return true;
-	if ((p->when & PASS_FSCK) && c->opts.fsck)
-		return true;
-	if ((p->when & PASS_UNCLEAN) && !c->sb.clean)
-		return true;
-	if (p->when & PASS_ALWAYS)
-		return true;
-	return false;
-}
-
-static int bch2_run_recovery_pass(struct bch_fs *c, enum bch_recovery_pass pass)
-{
-	struct recovery_pass_fn *p = recovery_pass_fns + pass;
-	int ret;
-
-	if (!(p->when & PASS_SILENT))
-		bch2_print(c, KERN_INFO bch2_log_msg(c, "%s..."),
-			   bch2_recovery_passes[pass]);
-	ret = p->fn(c);
-	if (ret)
-		return ret;
-	if (!(p->when & PASS_SILENT))
-		bch2_print(c, KERN_CONT " done\n");
-
-	return 0;
-}
-
-static int bch2_run_recovery_passes(struct bch_fs *c)
-{
-	int ret = 0;
-
-	while (c->curr_recovery_pass < ARRAY_SIZE(recovery_pass_fns)) {
-		if (should_run_recovery_pass(c, c->curr_recovery_pass)) {
-			unsigned pass = c->curr_recovery_pass;
-
-			ret = bch2_run_recovery_pass(c, c->curr_recovery_pass);
-			if (bch2_err_matches(ret, BCH_ERR_restart_recovery) ||
-			    (ret && c->curr_recovery_pass < pass))
-				continue;
-			if (ret)
-				break;
-
-			c->recovery_passes_complete |= BIT_ULL(c->curr_recovery_pass);
-		}
-		c->curr_recovery_pass++;
-		c->recovery_pass_done = max(c->recovery_pass_done, c->curr_recovery_pass);
-	}
-
-	return ret;
-}
-
-int bch2_run_online_recovery_passes(struct bch_fs *c)
-{
-	int ret = 0;
-
-	for (unsigned i = 0; i < ARRAY_SIZE(recovery_pass_fns); i++) {
-		struct recovery_pass_fn *p = recovery_pass_fns + i;
-
-		if (!(p->when & PASS_ONLINE))
-			continue;
-
-		ret = bch2_run_recovery_pass(c, i);
-		if (bch2_err_matches(ret, BCH_ERR_restart_recovery)) {
-			i = c->curr_recovery_pass;
-			continue;
-		}
-		if (ret)
-			break;
-	}
-
-	return ret;
-}
-
 int bch2_fs_recovery(struct bch_fs *c)
 {
 	struct bch_sb_field_clean *clean = NULL;
@@ -1155,7 +916,7 @@ int bch2_fs_initialize(struct bch_fs *c)
 	}
 	mutex_unlock(&c->sb_lock);
 
-	c->curr_recovery_pass = ARRAY_SIZE(recovery_pass_fns);
+	c->curr_recovery_pass = BCH_RECOVERY_PASS_NR;
 	set_bit(BCH_FS_may_go_rw, &c->flags);
 
 	for (unsigned i = 0; i < BTREE_ID_NR; i++)
@@ -1230,7 +991,7 @@ int bch2_fs_initialize(struct bch_fs *c)
 	if (ret)
 		goto err;
 
-	c->recovery_pass_done = ARRAY_SIZE(recovery_pass_fns) - 1;
+	c->recovery_pass_done = BCH_RECOVERY_PASS_NR - 1;
 
 	if (enabled_qtypes(c)) {
 		ret = bch2_fs_quota_read(c);

fs/bcachefs/recovery.h

@@ -2,37 +2,7 @@
 #ifndef _BCACHEFS_RECOVERY_H
 #define _BCACHEFS_RECOVERY_H
 
-extern const char * const bch2_recovery_passes[];
-
-u64 bch2_recovery_passes_to_stable(u64 v);
-u64 bch2_recovery_passes_from_stable(u64 v);
-
-/*
- * For when we need to rewind recovery passes and run a pass we skipped:
- */
-static inline int bch2_run_explicit_recovery_pass(struct bch_fs *c,
-						  enum bch_recovery_pass pass)
-{
-	if (c->recovery_passes_explicit & BIT_ULL(pass))
-		return 0;
-
-	bch_info(c, "running explicit recovery pass %s (%u), currently at %s (%u)",
-		 bch2_recovery_passes[pass], pass,
-		 bch2_recovery_passes[c->curr_recovery_pass], c->curr_recovery_pass);
-
-	c->recovery_passes_explicit |= BIT_ULL(pass);
-
-	if (c->curr_recovery_pass >= pass) {
-		c->curr_recovery_pass = pass;
-		c->recovery_passes_complete &= (1ULL << pass) >> 1;
-		return -BCH_ERR_restart_recovery;
-	} else {
-		return 0;
-	}
-}
-
-int bch2_run_online_recovery_passes(struct bch_fs *);
-u64 bch2_fsck_recovery_passes(void);
+int bch2_journal_replay(struct bch_fs *);
 
 int bch2_fs_recovery(struct bch_fs *);
 int bch2_fs_initialize(struct bch_fs *);

fs/bcachefs/recovery_passes.c

+// SPDX-License-Identifier: GPL-2.0
+
+#include "bcachefs.h"
+#include "alloc_background.h"
+#include "backpointers.h"
+#include "btree_gc.h"
+#include "ec.h"
+#include "fsck.h"
+#include "inode.h"
+#include "journal.h"
+#include "lru.h"
+#include "logged_ops.h"
+#include "rebalance.h"
+#include "recovery.h"
+#include "recovery_passes.h"
+#include "snapshot.h"
+#include "subvolume.h"
+#include "super.h"
+
+const char * const bch2_recovery_passes[] = {
+#define x(_fn, ...)	#_fn,
+	BCH_RECOVERY_PASSES()
+#undef x
+	NULL
+};
+
+static int bch2_check_allocations(struct bch_fs *c)
+{
+	return bch2_gc(c, true, c->opts.norecovery);
+}
+
+static int bch2_set_may_go_rw(struct bch_fs *c)
+{
+	struct journal_keys *keys = &c->journal_keys;
+
+	/*
+	 * After we go RW, the journal keys buffer can't be modified (except for
+	 * setting journal_key->overwritten: it will be accessed by multiple
+	 * threads
+	 */
+	move_gap(keys, keys->nr);
+
+	set_bit(BCH_FS_may_go_rw, &c->flags);
+
+	if (keys->nr || c->opts.fsck || !c->sb.clean)
+		return bch2_fs_read_write_early(c);
+	return 0;
+}
+
+struct recovery_pass_fn {
+	int		(*fn)(struct bch_fs *);
+	unsigned	when;
+};
+
+static struct recovery_pass_fn recovery_pass_fns[] = {
+#define x(_fn, _id, _when)	{ .fn = bch2_##_fn, .when = _when },
+	BCH_RECOVERY_PASSES()
+#undef x
+};
+
+u64 bch2_recovery_passes_to_stable(u64 v)
+{
+	static const u8 map[] = {
+#define x(n, id, ...)	[BCH_RECOVERY_PASS_##n] = BCH_RECOVERY_PASS_STABLE_##n,
+	BCH_RECOVERY_PASSES()
+#undef x
+	};
+
+	u64 ret = 0;
+	for (unsigned i = 0; i < ARRAY_SIZE(map); i++)
+		if (v & BIT_ULL(i))
+			ret |= BIT_ULL(map[i]);
+	return ret;
+}
+
+u64 bch2_recovery_passes_from_stable(u64 v)
+{
+	static const u8 map[] = {
+#define x(n, id, ...)	[BCH_RECOVERY_PASS_STABLE_##n] = BCH_RECOVERY_PASS_##n,
+	BCH_RECOVERY_PASSES()
+#undef x
+	};
+
+	u64 ret = 0;
+	for (unsigned i = 0; i < ARRAY_SIZE(map); i++)
+		if (v & BIT_ULL(i))
+			ret |= BIT_ULL(map[i]);
+	return ret;
+}
+
+/*
+ * For when we need to rewind recovery passes and run a pass we skipped:
+ */
+int bch2_run_explicit_recovery_pass(struct bch_fs *c,
+				    enum bch_recovery_pass pass)
+{
+	if (c->recovery_passes_explicit & BIT_ULL(pass))
+		return 0;
+
+	bch_info(c, "running explicit recovery pass %s (%u), currently at %s (%u)",
+		 bch2_recovery_passes[pass], pass,
+		 bch2_recovery_passes[c->curr_recovery_pass], c->curr_recovery_pass);
+
+	c->recovery_passes_explicit |= BIT_ULL(pass);
+
+	if (c->curr_recovery_pass >= pass) {
+		c->curr_recovery_pass = pass;
+		c->recovery_passes_complete &= (1ULL << pass) >> 1;
+		return -BCH_ERR_restart_recovery;
+	} else {
+		return 0;
+	}
+}
+
+u64 bch2_fsck_recovery_passes(void)
+{
+	u64 ret = 0;
+
+	for (unsigned i = 0; i < ARRAY_SIZE(recovery_pass_fns); i++)
+		if (recovery_pass_fns[i].when & PASS_FSCK)
+			ret |= BIT_ULL(i);
+	return ret;
+}
+
+static bool should_run_recovery_pass(struct bch_fs *c, enum bch_recovery_pass pass)
+{
+	struct recovery_pass_fn *p = recovery_pass_fns + pass;
+
+	if (c->opts.norecovery && pass > BCH_RECOVERY_PASS_snapshots_read)
+		return false;
+	if (c->recovery_passes_explicit & BIT_ULL(pass))
+		return true;
+	if ((p->when & PASS_FSCK) && c->opts.fsck)
+		return true;
+	if ((p->when & PASS_UNCLEAN) && !c->sb.clean)
+		return true;
+	if (p->when & PASS_ALWAYS)
+		return true;
+	return false;
+}
+
+static int bch2_run_recovery_pass(struct bch_fs *c, enum bch_recovery_pass pass)
+{
+	struct recovery_pass_fn *p = recovery_pass_fns + pass;
+	int ret;
+
+	if (!(p->when & PASS_SILENT))
+		bch2_print(c, KERN_INFO bch2_log_msg(c, "%s..."),
+			   bch2_recovery_passes[pass]);
+	ret = p->fn(c);
+	if (ret)
+		return ret;
+	if (!(p->when & PASS_SILENT))
+		bch2_print(c, KERN_CONT " done\n");
+
+	return 0;
+}
+
+int bch2_run_online_recovery_passes(struct bch_fs *c)
+{
+	int ret = 0;
+
+	for (unsigned i = 0; i < ARRAY_SIZE(recovery_pass_fns); i++) {
+		struct recovery_pass_fn *p = recovery_pass_fns + i;
+
+		if (!(p->when & PASS_ONLINE))
+			continue;
+
+		ret = bch2_run_recovery_pass(c, i);
+		if (bch2_err_matches(ret, BCH_ERR_restart_recovery)) {
+			i = c->curr_recovery_pass;
+			continue;
+		}
+		if (ret)
+			break;
+	}
+
+	return ret;
+}
+
+int bch2_run_recovery_passes(struct bch_fs *c)
+{
+	int ret = 0;
+
+	while (c->curr_recovery_pass < ARRAY_SIZE(recovery_pass_fns)) {
+		if (should_run_recovery_pass(c, c->curr_recovery_pass)) {
+			unsigned pass = c->curr_recovery_pass;
+
+			ret = bch2_run_recovery_pass(c, c->curr_recovery_pass);
+			if (bch2_err_matches(ret, BCH_ERR_restart_recovery) ||
+			    (ret && c->curr_recovery_pass < pass))
+				continue;
+			if (ret)
+				break;
+
+			c->recovery_passes_complete |= BIT_ULL(c->curr_recovery_pass);
+		}
+		c->curr_recovery_pass++;
+		c->recovery_pass_done = max(c->recovery_pass_done, c->curr_recovery_pass);
+	}
+
+	return ret;
+}

fs/bcachefs/recovery_passes.h

+#ifndef _BCACHEFS_RECOVERY_PASSES_H
+#define _BCACHEFS_RECOVERY_PASSES_H
+
+extern const char * const bch2_recovery_passes[];
+
+u64 bch2_recovery_passes_to_stable(u64 v);
+u64 bch2_recovery_passes_from_stable(u64 v);
+
+u64 bch2_fsck_recovery_passes(void);
+
+int bch2_run_explicit_recovery_pass(struct bch_fs *, enum bch_recovery_pass);
+
+int bch2_run_online_recovery_passes(struct bch_fs *);
+int bch2_run_recovery_passes(struct bch_fs *);
+
+#endif /* _BCACHEFS_RECOVERY_PASSES_H */

fs/bcachefs/recovery_types.h → fs/bcachefs/recovery_passes_types.h

 /* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _BCACHEFS_RECOVERY_TYPES_H
-#define _BCACHEFS_RECOVERY_TYPES_H
+#ifndef _BCACHEFS_RECOVERY_PASSES_TYPES_H
+#define _BCACHEFS_RECOVERY_PASSES_TYPES_H
 
 #define PASS_SILENT		BIT(0)
 #define PASS_FSCK		BIT(1)
@@ -56,6 +56,7 @@ enum bch_recovery_pass {
 #define x(n, id, when)	BCH_RECOVERY_PASS_##n,
 	BCH_RECOVERY_PASSES()
 #undef x
+	BCH_RECOVERY_PASS_NR
 };
 
 /* But we also need stable identifiers that can be used in the superblock */
@@ -65,4 +66,4 @@ enum bch_recovery_pass_stable {
 #undef x
 };
 
-#endif /* _BCACHEFS_RECOVERY_TYPES_H */
+#endif /* _BCACHEFS_RECOVERY_PASSES_TYPES_H */

fs/bcachefs/sb-downgrade.c

@@ -7,7 +7,7 @@
 
 #include "bcachefs.h"
 #include "darray.h"
-#include "recovery.h"
+#include "recovery_passes.h"
 #include "sb-downgrade.h"
 #include "sb-errors.h"
 #include "super-io.h"

fs/bcachefs/subvolume.c

@@ -595,6 +595,78 @@ int bch2_subvolume_create(struct btree_trans *trans, u64 inode,
 	return ret;
 }
 
+int bch2_initialize_subvolumes(struct bch_fs *c)
+{
+	struct bkey_i_snapshot_tree	root_tree;
+	struct bkey_i_snapshot		root_snapshot;
+	struct bkey_i_subvolume		root_volume;
+	int ret;
+
+	bkey_snapshot_tree_init(&root_tree.k_i);
+	root_tree.k.p.offset		= 1;
+	root_tree.v.master_subvol	= cpu_to_le32(1);
+	root_tree.v.root_snapshot	= cpu_to_le32(U32_MAX);
+
+	bkey_snapshot_init(&root_snapshot.k_i);
+	root_snapshot.k.p.offset = U32_MAX;
+	root_snapshot.v.flags	= 0;
+	root_snapshot.v.parent	= 0;
+	root_snapshot.v.subvol	= cpu_to_le32(BCACHEFS_ROOT_SUBVOL);
+	root_snapshot.v.tree	= cpu_to_le32(1);
+	SET_BCH_SNAPSHOT_SUBVOL(&root_snapshot.v, true);
+
+	bkey_subvolume_init(&root_volume.k_i);
+	root_volume.k.p.offset = BCACHEFS_ROOT_SUBVOL;
+	root_volume.v.flags	= 0;
+	root_volume.v.snapshot	= cpu_to_le32(U32_MAX);
+	root_volume.v.inode	= cpu_to_le64(BCACHEFS_ROOT_INO);
+
+	ret =   bch2_btree_insert(c, BTREE_ID_snapshot_trees,	&root_tree.k_i, NULL, 0) ?:
+		bch2_btree_insert(c, BTREE_ID_snapshots,	&root_snapshot.k_i, NULL, 0) ?:
+		bch2_btree_insert(c, BTREE_ID_subvolumes,	&root_volume.k_i, NULL, 0);
+	bch_err_fn(c, ret);
+	return ret;
+}
+
+static int __bch2_fs_upgrade_for_subvolumes(struct btree_trans *trans)
+{
+	struct btree_iter iter;
+	struct bkey_s_c k;
+	struct bch_inode_unpacked inode;
+	int ret;
+
+	k = bch2_bkey_get_iter(trans, &iter, BTREE_ID_inodes,
+			       SPOS(0, BCACHEFS_ROOT_INO, U32_MAX), 0);
+	ret = bkey_err(k);
+	if (ret)
+		return ret;
+
+	if (!bkey_is_inode(k.k)) {
+		bch_err(trans->c, "root inode not found");
+		ret = -BCH_ERR_ENOENT_inode;
+		goto err;
+	}
+
+	ret = bch2_inode_unpack(k, &inode);
+	BUG_ON(ret);
+
+	inode.bi_subvol = BCACHEFS_ROOT_SUBVOL;
+
+	ret = bch2_inode_write(trans, &iter, &inode);
+err:
+	bch2_trans_iter_exit(trans, &iter);
+	return ret;
+}
+
+/* set bi_subvol on root inode */
+int bch2_fs_upgrade_for_subvolumes(struct bch_fs *c)
+{
+	int ret = bch2_trans_do(c, NULL, NULL, BCH_TRANS_COMMIT_lazy_rw,
+				__bch2_fs_upgrade_for_subvolumes(trans));
+	bch_err_fn(c, ret);
+	return ret;
+}
+
 int bch2_fs_subvolumes_init(struct bch_fs *c)
 {
 	INIT_WORK(&c->snapshot_delete_work, bch2_delete_dead_snapshots_work);

fs/bcachefs/subvolume.h

@@ -37,6 +37,9 @@ void bch2_delete_dead_snapshots_async(struct bch_fs *);
 int bch2_subvolume_unlink(struct btree_trans *, u32);
 int bch2_subvolume_create(struct btree_trans *, u64, u32, u32, u32 *, u32 *, bool);
 
+int bch2_initialize_subvolumes(struct bch_fs *);
+int bch2_fs_upgrade_for_subvolumes(struct bch_fs *);
+
 int bch2_fs_subvolumes_init(struct bch_fs *);
 
 #endif /* _BCACHEFS_SUBVOLUME_H */

fs/bcachefs/super-io.c

@@ -8,7 +8,7 @@
 #include "journal.h"
 #include "journal_sb.h"
 #include "journal_seq_blacklist.h"
-#include "recovery.h"
+#include "recovery_passes.h"
 #include "replicas.h"
 #include "quota.h"
 #include "sb-clean.h"