1 files changed, 0 insertions, 752 deletions

diff --git a/fs/bcachefs/subvolume.c b/fs/bcachefs/subvolume.c
deleted file mode 100644
index 020587449123..000000000000
--- a/fs/bcachefs/subvolume.c
+++ /dev/null
@@ -1,752 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-
-#include "bcachefs.h"
-#include "btree_key_cache.h"
-#include "btree_update.h"
-#include "enumerated_ref.h"
-#include "errcode.h"
-#include "error.h"
-#include "fs.h"
-#include "recovery_passes.h"
-#include "snapshot.h"
-#include "subvolume.h"
-
-#include <linux/random.h>
-
-static int bch2_subvolume_delete(struct btree_trans *, u32);
-
-static int bch2_subvolume_missing(struct bch_fs *c, u32 subvolid)
-{
-	struct printbuf buf = PRINTBUF;
-	bch2_log_msg_start(c, &buf);
-
-	prt_printf(&buf, "missing subvolume %u", subvolid);
-	bool print = bch2_count_fsck_err(c, subvol_missing, &buf);
-
-	int ret = bch2_run_explicit_recovery_pass(c, &buf,
-					BCH_RECOVERY_PASS_check_inodes, 0);
-	if (print)
-		bch2_print_str(c, KERN_ERR, buf.buf);
-	printbuf_exit(&buf);
-	return ret;
-}
-
-static struct bpos subvolume_children_pos(struct bkey_s_c k)
-{
-	if (k.k->type != KEY_TYPE_subvolume)
-		return POS_MIN;
-
-	struct bkey_s_c_subvolume s = bkey_s_c_to_subvolume(k);
-	if (!s.v->fs_path_parent)
-		return POS_MIN;
-	return POS(le32_to_cpu(s.v->fs_path_parent), s.k->p.offset);
-}
-
-static int check_subvol(struct btree_trans *trans,
-			struct btree_iter *iter,
-			struct bkey_s_c k)
-{
-	struct bch_fs *c = trans->c;
-	struct bkey_s_c_subvolume subvol;
-	struct btree_iter subvol_children_iter = {};
-	struct bch_snapshot snapshot;
-	struct printbuf buf = PRINTBUF;
-	unsigned snapid;
-	int ret = 0;
-
-	if (k.k->type != KEY_TYPE_subvolume)
-		return 0;
-
-	subvol = bkey_s_c_to_subvolume(k);
-	snapid = le32_to_cpu(subvol.v->snapshot);
-	ret = bch2_snapshot_lookup(trans, snapid, &snapshot);
-
-	if (bch2_err_matches(ret, ENOENT))
-		return bch2_run_print_explicit_recovery_pass(c,
-					BCH_RECOVERY_PASS_reconstruct_snapshots) ?: ret;
-	if (ret)
-		return ret;
-
-	if (BCH_SUBVOLUME_UNLINKED(subvol.v)) {
-		ret = bch2_subvolume_delete(trans, iter->pos.offset);
-		bch_err_msg(c, ret, "deleting subvolume %llu", iter->pos.offset);
-		return ret ?: -BCH_ERR_transaction_restart_nested;
-	}
-
-	if (fsck_err_on(subvol.k->p.offset == BCACHEFS_ROOT_SUBVOL &&
-			subvol.v->fs_path_parent,
-			trans, subvol_root_fs_path_parent_nonzero,
-			"root subvolume has nonzero fs_path_parent\n%s",
-			(bch2_bkey_val_to_text(&buf, c, k), buf.buf))) {
-		struct bkey_i_subvolume *n =
-			bch2_bkey_make_mut_typed(trans, iter, &subvol.s_c, 0, subvolume);
-		ret = PTR_ERR_OR_ZERO(n);
-		if (ret)
-			goto err;
-
-		n->v.fs_path_parent = 0;
-	}
-
-	if (subvol.v->fs_path_parent) {
-		struct bpos pos = subvolume_children_pos(k);
-
-		struct bkey_s_c subvol_children_k =
-			bch2_bkey_get_iter(trans, &subvol_children_iter,
-					   BTREE_ID_subvolume_children, pos, 0);
-		ret = bkey_err(subvol_children_k);
-		if (ret)
-			goto err;
-
-		if (fsck_err_on(subvol_children_k.k->type != KEY_TYPE_set,
-				trans, subvol_children_not_set,
-				"subvolume not set in subvolume_children btree at %llu:%llu\n%s",
-				pos.inode, pos.offset,
-				(printbuf_reset(&buf),
-				 bch2_bkey_val_to_text(&buf, c, k), buf.buf))) {
-			ret = bch2_btree_bit_mod(trans, BTREE_ID_subvolume_children, pos, true);
-			if (ret)
-				goto err;
-		}
-	}
-
-	struct bch_inode_unpacked inode;
-	ret = bch2_inode_find_by_inum_nowarn_trans(trans,
-				    (subvol_inum) { k.k->p.offset, le64_to_cpu(subvol.v->inode) },
-				    &inode);
-	if (!ret) {
-		if (fsck_err_on(inode.bi_subvol != subvol.k->p.offset,
-				trans, subvol_root_wrong_bi_subvol,
-				"subvol root %llu:%u has wrong bi_subvol field: got %u, should be %llu",
-				inode.bi_inum, inode.bi_snapshot,
-				inode.bi_subvol, subvol.k->p.offset)) {
-			inode.bi_subvol = subvol.k->p.offset;
-			inode.bi_snapshot = le32_to_cpu(subvol.v->snapshot);
-			ret = __bch2_fsck_write_inode(trans, &inode);
-			if (ret)
-				goto err;
-		}
-	} else if (bch2_err_matches(ret, ENOENT)) {
-		if (fsck_err(trans, subvol_to_missing_root,
-			     "subvolume %llu points to missing subvolume root %llu:%u",
-			     k.k->p.offset, le64_to_cpu(subvol.v->inode),
-			     le32_to_cpu(subvol.v->snapshot))) {
-			/*
-			 * Recreate - any contents that are still disconnected
-			 * will then get reattached under lost+found
-			 */
-			bch2_inode_init_early(c, &inode);
-			bch2_inode_init_late(c, &inode, bch2_current_time(c),
-					     0, 0, S_IFDIR|0700, 0, NULL);
-			inode.bi_inum			= le64_to_cpu(subvol.v->inode);
-			inode.bi_snapshot		= le32_to_cpu(subvol.v->snapshot);
-			inode.bi_subvol			= k.k->p.offset;
-			inode.bi_parent_subvol		= le32_to_cpu(subvol.v->fs_path_parent);
-			ret = __bch2_fsck_write_inode(trans, &inode);
-			if (ret)
-				goto err;
-		}
-	} else {
-		goto err;
-	}
-
-	if (!BCH_SUBVOLUME_SNAP(subvol.v)) {
-		u32 snapshot_root = bch2_snapshot_root(c, le32_to_cpu(subvol.v->snapshot));
-		u32 snapshot_tree = bch2_snapshot_tree(c, snapshot_root);
-
-		struct bch_snapshot_tree st;
-		ret = bch2_snapshot_tree_lookup(trans, snapshot_tree, &st);
-
-		bch2_fs_inconsistent_on(bch2_err_matches(ret, ENOENT), c,
-				"%s: snapshot tree %u not found", __func__, snapshot_tree);
-
-		if (ret)
-			goto err;
-
-		if (fsck_err_on(le32_to_cpu(st.master_subvol) != subvol.k->p.offset,
-				trans, subvol_not_master_and_not_snapshot,
-				"subvolume %llu is not set as snapshot but is not master subvolume",
-				k.k->p.offset)) {
-			struct bkey_i_subvolume *s =
-				bch2_bkey_make_mut_typed(trans, iter, &subvol.s_c, 0, subvolume);
-			ret = PTR_ERR_OR_ZERO(s);
-			if (ret)
-				goto err;
-
-			SET_BCH_SUBVOLUME_SNAP(&s->v, true);
-		}
-	}
-err:
-fsck_err:
-	bch2_trans_iter_exit(trans, &subvol_children_iter);
-	printbuf_exit(&buf);
-	return ret;
-}
-
-int bch2_check_subvols(struct bch_fs *c)
-{
-	int ret = bch2_trans_run(c,
-		for_each_btree_key_commit(trans, iter,
-				BTREE_ID_subvolumes, POS_MIN, BTREE_ITER_prefetch, k,
-				NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
-			check_subvol(trans, &iter, k)));
-	bch_err_fn(c, ret);
-	return ret;
-}
-
-static int check_subvol_child(struct btree_trans *trans,
-			      struct btree_iter *child_iter,
-			      struct bkey_s_c child_k)
-{
-	struct bch_subvolume s;
-	int ret = bch2_bkey_get_val_typed(trans, BTREE_ID_subvolumes, POS(0, child_k.k->p.offset),
-					  0, subvolume, &s);
-	if (ret && !bch2_err_matches(ret, ENOENT))
-		return ret;
-
-	if (fsck_err_on(ret ||
-			le32_to_cpu(s.fs_path_parent) != child_k.k->p.inode,
-			trans, subvol_children_bad,
-			"incorrect entry in subvolume_children btree %llu:%llu",
-			child_k.k->p.inode, child_k.k->p.offset)) {
-		ret = bch2_btree_delete_at(trans, child_iter, 0);
-		if (ret)
-			goto err;
-	}
-err:
-fsck_err:
-	return ret;
-}
-
-int bch2_check_subvol_children(struct bch_fs *c)
-{
-	int ret = bch2_trans_run(c,
-		for_each_btree_key_commit(trans, iter,
-				BTREE_ID_subvolume_children, POS_MIN, BTREE_ITER_prefetch, k,
-				NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
-			check_subvol_child(trans, &iter, k)));
-	bch_err_fn(c, ret);
-	return 0;
-}
-
-/* Subvolumes: */
-
-int bch2_subvolume_validate(struct bch_fs *c, struct bkey_s_c k,
-			    struct bkey_validate_context from)
-{
-	struct bkey_s_c_subvolume subvol = bkey_s_c_to_subvolume(k);
-	int ret = 0;
-
-	bkey_fsck_err_on(bkey_lt(k.k->p, SUBVOL_POS_MIN) ||
-			 bkey_gt(k.k->p, SUBVOL_POS_MAX),
-			 c, subvol_pos_bad,
-			 "invalid pos");
-
-	bkey_fsck_err_on(!subvol.v->snapshot,
-			 c, subvol_snapshot_bad,
-			 "invalid snapshot");
-
-	bkey_fsck_err_on(!subvol.v->inode,
-			 c, subvol_inode_bad,
-			 "invalid inode");
-fsck_err:
-	return ret;
-}
-
-void bch2_subvolume_to_text(struct printbuf *out, struct bch_fs *c,
-			    struct bkey_s_c k)
-{
-	struct bkey_s_c_subvolume s = bkey_s_c_to_subvolume(k);
-
-	prt_printf(out, "root %llu snapshot id %u",
-		   le64_to_cpu(s.v->inode),
-		   le32_to_cpu(s.v->snapshot));
-
-	if (bkey_val_bytes(s.k) > offsetof(struct bch_subvolume, creation_parent)) {
-		prt_printf(out, " creation_parent %u", le32_to_cpu(s.v->creation_parent));
-		prt_printf(out, " fs_parent %u", le32_to_cpu(s.v->fs_path_parent));
-	}
-
-	if (BCH_SUBVOLUME_RO(s.v))
-		prt_printf(out, " ro");
-	if (BCH_SUBVOLUME_SNAP(s.v))
-		prt_printf(out, " snapshot");
-	if (BCH_SUBVOLUME_UNLINKED(s.v))
-		prt_printf(out, " unlinked");
-}
-
-static int subvolume_children_mod(struct btree_trans *trans, struct bpos pos, bool set)
-{
-	return !bpos_eq(pos, POS_MIN)
-		? bch2_btree_bit_mod(trans, BTREE_ID_subvolume_children, pos, set)
-		: 0;
-}
-
-int bch2_subvolume_trigger(struct btree_trans *trans,
-			   enum btree_id btree_id, unsigned level,
-			   struct bkey_s_c old, struct bkey_s new,
-			   enum btree_iter_update_trigger_flags flags)
-{
-	if (flags & BTREE_TRIGGER_transactional) {
-		struct bpos children_pos_old = subvolume_children_pos(old);
-		struct bpos children_pos_new = subvolume_children_pos(new.s_c);
-
-		if (!bpos_eq(children_pos_old, children_pos_new)) {
-			int ret = subvolume_children_mod(trans, children_pos_old, false) ?:
-				  subvolume_children_mod(trans, children_pos_new, true);
-			if (ret)
-				return ret;
-		}
-	}
-
-	return 0;
-}
-
-int bch2_subvol_has_children(struct btree_trans *trans, u32 subvol)
-{
-	struct btree_iter iter;
-
-	bch2_trans_iter_init(trans, &iter, BTREE_ID_subvolume_children, POS(subvol, 0), 0);
-	struct bkey_s_c k = bch2_btree_iter_peek(trans, &iter);
-	bch2_trans_iter_exit(trans, &iter);
-
-	return bkey_err(k) ?: k.k && k.k->p.inode == subvol
-		? -BCH_ERR_ENOTEMPTY_subvol_not_empty
-		: 0;
-}
-
-static __always_inline int
-bch2_subvolume_get_inlined(struct btree_trans *trans, unsigned subvol,
-			   bool inconsistent_if_not_found,
-			   struct bch_subvolume *s)
-{
-	int ret = bch2_bkey_get_val_typed(trans, BTREE_ID_subvolumes, POS(0, subvol),
-					  BTREE_ITER_cached|
-					  BTREE_ITER_with_updates, subvolume, s);
-	if (bch2_err_matches(ret, ENOENT) && inconsistent_if_not_found)
-		ret = bch2_subvolume_missing(trans->c, subvol) ?: ret;
-	return ret;
-}
-
-int bch2_subvolume_get(struct btree_trans *trans, unsigned subvol,
-		       bool inconsistent_if_not_found,
-		       struct bch_subvolume *s)
-{
-	return bch2_subvolume_get_inlined(trans, subvol, inconsistent_if_not_found, s);
-}
-
-int bch2_subvol_is_ro_trans(struct btree_trans *trans, u32 subvol)
-{
-	struct bch_subvolume s;
-	int ret = bch2_subvolume_get_inlined(trans, subvol, true, &s);
-	if (ret)
-		return ret;
-
-	if (BCH_SUBVOLUME_RO(&s))
-		return -EROFS;
-	return 0;
-}
-
-int bch2_subvol_is_ro(struct bch_fs *c, u32 subvol)
-{
-	return bch2_trans_do(c, bch2_subvol_is_ro_trans(trans, subvol));
-}
-
-int bch2_snapshot_get_subvol(struct btree_trans *trans, u32 snapshot,
-			     struct bch_subvolume *subvol)
-{
-	struct bch_snapshot snap;
-
-	return  bch2_snapshot_lookup(trans, snapshot, &snap) ?:
-		bch2_subvolume_get(trans, le32_to_cpu(snap.subvol), true, subvol);
-}
-
-int __bch2_subvolume_get_snapshot(struct btree_trans *trans, u32 subvolid,
-				  u32 *snapid, bool warn)
-{
-	struct btree_iter iter;
-	struct bkey_s_c_subvolume subvol;
-	int ret;
-
-	subvol = bch2_bkey_get_iter_typed(trans, &iter,
-					  BTREE_ID_subvolumes, POS(0, subvolid),
-					  BTREE_ITER_cached|BTREE_ITER_with_updates,
-					  subvolume);
-	ret = bkey_err(subvol);
-
-	if (bch2_err_matches(ret, ENOENT))
-		ret = bch2_subvolume_missing(trans->c, subvolid) ?: ret;
-
-	if (likely(!ret))
-		*snapid = le32_to_cpu(subvol.v->snapshot);
-	bch2_trans_iter_exit(trans, &iter);
-	return ret;
-}
-
-int bch2_subvolume_get_snapshot(struct btree_trans *trans, u32 subvolid,
-				u32 *snapid)
-{
-	return __bch2_subvolume_get_snapshot(trans, subvolid, snapid, true);
-}
-
-static int bch2_subvolume_reparent(struct btree_trans *trans,
-				   struct btree_iter *iter,
-				   struct bkey_s_c k,
-				   u32 old_parent, u32 new_parent)
-{
-	struct bkey_i_subvolume *s;
-	int ret;
-
-	if (k.k->type != KEY_TYPE_subvolume)
-		return 0;
-
-	if (bkey_val_bytes(k.k) > offsetof(struct bch_subvolume, creation_parent) &&
-	    le32_to_cpu(bkey_s_c_to_subvolume(k).v->creation_parent) != old_parent)
-		return 0;
-
-	s = bch2_bkey_make_mut_typed(trans, iter, &k, 0, subvolume);
-	ret = PTR_ERR_OR_ZERO(s);
-	if (ret)
-		return ret;
-
-	s->v.creation_parent = cpu_to_le32(new_parent);
-	return 0;
-}
-
-/*
- * Separate from the snapshot tree in the snapshots btree, we record the tree
- * structure of how snapshot subvolumes were created - the parent subvolume of
- * each snapshot subvolume.
- *
- * When a subvolume is deleted, we scan for child subvolumes and reparant them,
- * to avoid dangling references:
- */
-static int bch2_subvolumes_reparent(struct btree_trans *trans, u32 subvolid_to_delete)
-{
-	struct bch_subvolume s;
-
-	return lockrestart_do(trans,
-			bch2_subvolume_get(trans, subvolid_to_delete, true, &s)) ?:
-		for_each_btree_key_commit(trans, iter,
-				BTREE_ID_subvolumes, POS_MIN, BTREE_ITER_prefetch, k,
-				NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
-			bch2_subvolume_reparent(trans, &iter, k,
-					subvolid_to_delete, le32_to_cpu(s.creation_parent)));
-}
-
-/*
- * Delete subvolume, mark snapshot ID as deleted, queue up snapshot
- * deletion/cleanup:
- */
-static int __bch2_subvolume_delete(struct btree_trans *trans, u32 subvolid)
-{
-	struct btree_iter subvol_iter = {}, snapshot_iter = {}, snapshot_tree_iter = {};
-
-	struct bkey_s_c_subvolume subvol =
-		bch2_bkey_get_iter_typed(trans, &subvol_iter,
-				BTREE_ID_subvolumes, POS(0, subvolid),
-				BTREE_ITER_cached|BTREE_ITER_intent,
-				subvolume);
-	int ret = bkey_err(subvol);
-	if (bch2_err_matches(ret, ENOENT))
-		ret = bch2_subvolume_missing(trans->c, subvolid) ?: ret;
-	if (ret)
-		goto err;
-
-	u32 snapid = le32_to_cpu(subvol.v->snapshot);
-
-	struct bkey_s_c_snapshot snapshot =
-		bch2_bkey_get_iter_typed(trans, &snapshot_iter,
-				BTREE_ID_snapshots, POS(0, snapid),
-				0, snapshot);
-	ret = bkey_err(snapshot);
-	bch2_fs_inconsistent_on(bch2_err_matches(ret, ENOENT), trans->c,
-				"missing snapshot %u", snapid);
-	if (ret)
-		goto err;
-
-	u32 treeid = le32_to_cpu(snapshot.v->tree);
-
-	struct bkey_s_c_snapshot_tree snapshot_tree =
-		bch2_bkey_get_iter_typed(trans, &snapshot_tree_iter,
-				BTREE_ID_snapshot_trees, POS(0, treeid),
-				0, snapshot_tree);
-	ret = bkey_err(snapshot_tree);
-	bch2_fs_inconsistent_on(bch2_err_matches(ret, ENOENT), trans->c,
-				"missing snapshot tree %u", treeid);
-	if (ret)
-		goto err;
-
-	if (le32_to_cpu(snapshot_tree.v->master_subvol) == subvolid) {
-		struct bkey_i_snapshot_tree *snapshot_tree_mut =
-			bch2_bkey_make_mut_typed(trans, &snapshot_tree_iter,
-						 &snapshot_tree.s_c,
-						 0, snapshot_tree);
-		ret = PTR_ERR_OR_ZERO(snapshot_tree_mut);
-		if (ret)
-			goto err;
-
-		snapshot_tree_mut->v.master_subvol = 0;
-	}
-
-	ret =   bch2_btree_delete_at(trans, &subvol_iter, 0) ?:
-		bch2_snapshot_node_set_deleted(trans, snapid);
-err:
-	bch2_trans_iter_exit(trans, &snapshot_tree_iter);
-	bch2_trans_iter_exit(trans, &snapshot_iter);
-	bch2_trans_iter_exit(trans, &subvol_iter);
-	return ret;
-}
-
-static int bch2_subvolume_delete(struct btree_trans *trans, u32 subvolid)
-{
-	int ret = bch2_subvolumes_reparent(trans, subvolid) ?:
-		commit_do(trans, NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
-			  __bch2_subvolume_delete(trans, subvolid));
-
-	bch2_recovery_pass_set_no_ratelimit(trans->c, BCH_RECOVERY_PASS_check_subvols);
-	return ret;
-}
-
-static void bch2_subvolume_wait_for_pagecache_and_delete(struct work_struct *work)
-{
-	struct bch_fs *c = container_of(work, struct bch_fs,
-				snapshot_wait_for_pagecache_and_delete_work);
-	int ret = 0;
-
-	while (!ret) {
-		mutex_lock(&c->snapshots_unlinked_lock);
-		snapshot_id_list s = c->snapshots_unlinked;
-		darray_init(&c->snapshots_unlinked);
-		mutex_unlock(&c->snapshots_unlinked_lock);
-
-		if (!s.nr)
-			break;
-
-		bch2_evict_subvolume_inodes(c, &s);
-
-		darray_for_each(s, id) {
-			ret = bch2_trans_run(c, bch2_subvolume_delete(trans, *id));
-			bch_err_msg(c, ret, "deleting subvolume %u", *id);
-			if (ret)
-				break;
-		}
-
-		darray_exit(&s);
-	}
-
-	enumerated_ref_put(&c->writes, BCH_WRITE_REF_snapshot_delete_pagecache);
-}
-
-struct subvolume_unlink_hook {
-	struct btree_trans_commit_hook	h;
-	u32				subvol;
-};
-
-static int bch2_subvolume_wait_for_pagecache_and_delete_hook(struct btree_trans *trans,
-						      struct btree_trans_commit_hook *_h)
-{
-	struct subvolume_unlink_hook *h = container_of(_h, struct subvolume_unlink_hook, h);
-	struct bch_fs *c = trans->c;
-	int ret = 0;
-
-	mutex_lock(&c->snapshots_unlinked_lock);
-	if (!snapshot_list_has_id(&c->snapshots_unlinked, h->subvol))
-		ret = snapshot_list_add(c, &c->snapshots_unlinked, h->subvol);
-	mutex_unlock(&c->snapshots_unlinked_lock);
-
-	if (ret)
-		return ret;
-
-	if (!enumerated_ref_tryget(&c->writes, BCH_WRITE_REF_snapshot_delete_pagecache))
-		return -EROFS;
-
-	if (!queue_work(c->write_ref_wq, &c->snapshot_wait_for_pagecache_and_delete_work))
-		enumerated_ref_put(&c->writes, BCH_WRITE_REF_snapshot_delete_pagecache);
-	return 0;
-}
-
-int bch2_subvolume_unlink(struct btree_trans *trans, u32 subvolid)
-{
-	struct btree_iter iter;
-	struct bkey_i_subvolume *n;
-	struct subvolume_unlink_hook *h;
-	int ret = 0;
-
-	h = bch2_trans_kmalloc(trans, sizeof(*h));
-	ret = PTR_ERR_OR_ZERO(h);
-	if (ret)
-		return ret;
-
-	h->h.fn		= bch2_subvolume_wait_for_pagecache_and_delete_hook;
-	h->subvol	= subvolid;
-	bch2_trans_commit_hook(trans, &h->h);
-
-	n = bch2_bkey_get_mut_typed(trans, &iter,
-			BTREE_ID_subvolumes, POS(0, subvolid),
-			BTREE_ITER_cached, subvolume);
-	ret = PTR_ERR_OR_ZERO(n);
-	if (bch2_err_matches(ret, ENOENT))
-		ret = bch2_subvolume_missing(trans->c, subvolid) ?: ret;
-	if (unlikely(ret))
-		return ret;
-
-	SET_BCH_SUBVOLUME_UNLINKED(&n->v, true);
-	n->v.fs_path_parent = 0;
-	bch2_trans_iter_exit(trans, &iter);
-	return ret;
-}
-
-int bch2_subvolume_create(struct btree_trans *trans, u64 inode,
-			  u32 parent_subvolid,
-			  u32 src_subvolid,
-			  u32 *new_subvolid,
-			  u32 *new_snapshotid,
-			  bool ro)
-{
-	struct bch_fs *c = trans->c;
-	struct btree_iter dst_iter, src_iter = {};
-	struct bkey_i_subvolume *new_subvol = NULL;
-	struct bkey_i_subvolume *src_subvol = NULL;
-	u32 parent = 0, new_nodes[2], snapshot_subvols[2];
-	int ret = 0;
-
-	ret = bch2_bkey_get_empty_slot(trans, &dst_iter,
-				BTREE_ID_subvolumes, POS(0, U32_MAX));
-	if (ret == -BCH_ERR_ENOSPC_btree_slot)
-		ret = bch_err_throw(c, ENOSPC_subvolume_create);
-	if (ret)
-		return ret;
-
-	snapshot_subvols[0] = dst_iter.pos.offset;
-	snapshot_subvols[1] = src_subvolid;
-
-	if (src_subvolid) {
-		/* Creating a snapshot: */
-
-		src_subvol = bch2_bkey_get_mut_typed(trans, &src_iter,
-				BTREE_ID_subvolumes, POS(0, src_subvolid),
-				BTREE_ITER_cached, subvolume);
-		ret = PTR_ERR_OR_ZERO(src_subvol);
-		if (bch2_err_matches(ret, ENOENT))
-			ret = bch2_subvolume_missing(trans->c, src_subvolid) ?: ret;
-		if (unlikely(ret))
-			goto err;
-
-		parent = le32_to_cpu(src_subvol->v.snapshot);
-	}
-
-	ret = bch2_snapshot_node_create(trans, parent, new_nodes,
-					snapshot_subvols,
-					src_subvolid ? 2 : 1);
-	if (ret)
-		goto err;
-
-	if (src_subvolid) {
-		src_subvol->v.snapshot = cpu_to_le32(new_nodes[1]);
-		ret = bch2_trans_update(trans, &src_iter, &src_subvol->k_i, 0);
-		if (ret)
-			goto err;
-	}
-
-	new_subvol = bch2_bkey_alloc(trans, &dst_iter, 0, subvolume);
-	ret = PTR_ERR_OR_ZERO(new_subvol);
-	if (ret)
-		goto err;
-
-	new_subvol->v.flags		= 0;
-	new_subvol->v.snapshot		= cpu_to_le32(new_nodes[0]);
-	new_subvol->v.inode		= cpu_to_le64(inode);
-	new_subvol->v.creation_parent	= cpu_to_le32(src_subvolid);
-	new_subvol->v.fs_path_parent	= cpu_to_le32(parent_subvolid);
-	new_subvol->v.otime.lo		= cpu_to_le64(bch2_current_time(c));
-	new_subvol->v.otime.hi		= 0;
-
-	SET_BCH_SUBVOLUME_RO(&new_subvol->v, ro);
-	SET_BCH_SUBVOLUME_SNAP(&new_subvol->v, src_subvolid != 0);
-
-	*new_subvolid	= new_subvol->k.p.offset;
-	*new_snapshotid	= new_nodes[0];
-err:
-	bch2_trans_iter_exit(trans, &src_iter);
-	bch2_trans_iter_exit(trans, &dst_iter);
-	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, 0) ?:
-		bch2_btree_insert(c, BTREE_ID_snapshots,	&root_snapshot.k_i, NULL, 0, 0) ?:
-		bch2_btree_insert(c, BTREE_ID_subvolumes,	&root_volume.k_i, NULL, 0, 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)) {
-		struct bch_fs *c = trans->c;
-		bch_err(c, "root inode not found");
-		ret = bch_err_throw(c, 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_commit_do(c, NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
-				       __bch2_fs_upgrade_for_subvolumes(trans));
-	bch_err_fn(c, ret);
-	return ret;
-}
-
-void bch2_fs_subvolumes_init_early(struct bch_fs *c)
-{
-	INIT_WORK(&c->snapshot_wait_for_pagecache_and_delete_work,
-		  bch2_subvolume_wait_for_pagecache_and_delete);
-}