| // SPDX-License-Identifier: GPL-2.0 |
| |
| #include "bcachefs.h" |
| #include "btree_key_cache.h" |
| #include "btree_update.h" |
| #include "errcode.h" |
| #include "error.h" |
| #include "fs.h" |
| #include "subvolume.h" |
| |
| /* Snapshot tree: */ |
| |
| void bch2_snapshot_to_text(struct printbuf *out, struct bch_fs *c, |
| struct bkey_s_c k) |
| { |
| struct bkey_s_c_snapshot s = bkey_s_c_to_snapshot(k); |
| |
| prt_printf(out, "is_subvol %llu deleted %llu parent %10u children %10u %10u subvol %u", |
| BCH_SNAPSHOT_SUBVOL(s.v), |
| BCH_SNAPSHOT_DELETED(s.v), |
| le32_to_cpu(s.v->parent), |
| le32_to_cpu(s.v->children[0]), |
| le32_to_cpu(s.v->children[1]), |
| le32_to_cpu(s.v->subvol)); |
| } |
| |
| int bch2_snapshot_invalid(const struct bch_fs *c, struct bkey_s_c k, |
| unsigned flags, struct printbuf *err) |
| { |
| struct bkey_s_c_snapshot s; |
| u32 i, id; |
| |
| if (bkey_gt(k.k->p, POS(0, U32_MAX)) || |
| bkey_lt(k.k->p, POS(0, 1))) { |
| prt_printf(err, "bad pos"); |
| return -BCH_ERR_invalid_bkey; |
| } |
| |
| s = bkey_s_c_to_snapshot(k); |
| |
| id = le32_to_cpu(s.v->parent); |
| if (id && id <= k.k->p.offset) { |
| prt_printf(err, "bad parent node (%u <= %llu)", |
| id, k.k->p.offset); |
| return -BCH_ERR_invalid_bkey; |
| } |
| |
| if (le32_to_cpu(s.v->children[0]) < le32_to_cpu(s.v->children[1])) { |
| prt_printf(err, "children not normalized"); |
| return -BCH_ERR_invalid_bkey; |
| } |
| |
| if (s.v->children[0] && |
| s.v->children[0] == s.v->children[1]) { |
| prt_printf(err, "duplicate child nodes"); |
| return -BCH_ERR_invalid_bkey; |
| } |
| |
| for (i = 0; i < 2; i++) { |
| id = le32_to_cpu(s.v->children[i]); |
| |
| if (id >= k.k->p.offset) { |
| prt_printf(err, "bad child node (%u >= %llu)", |
| id, k.k->p.offset); |
| return -BCH_ERR_invalid_bkey; |
| } |
| } |
| |
| return 0; |
| } |
| |
| int bch2_mark_snapshot(struct btree_trans *trans, |
| enum btree_id btree, unsigned level, |
| struct bkey_s_c old, struct bkey_s_c new, |
| unsigned flags) |
| { |
| struct bch_fs *c = trans->c; |
| struct snapshot_t *t; |
| |
| t = genradix_ptr_alloc(&c->snapshots, |
| U32_MAX - new.k->p.offset, |
| GFP_KERNEL); |
| if (!t) |
| return -BCH_ERR_ENOMEM_mark_snapshot; |
| |
| if (new.k->type == KEY_TYPE_snapshot) { |
| struct bkey_s_c_snapshot s = bkey_s_c_to_snapshot(new); |
| |
| t->parent = le32_to_cpu(s.v->parent); |
| t->children[0] = le32_to_cpu(s.v->children[0]); |
| t->children[1] = le32_to_cpu(s.v->children[1]); |
| t->subvol = BCH_SNAPSHOT_SUBVOL(s.v) ? le32_to_cpu(s.v->subvol) : 0; |
| } else { |
| t->parent = 0; |
| t->children[0] = 0; |
| t->children[1] = 0; |
| t->subvol = 0; |
| } |
| |
| return 0; |
| } |
| |
| static int snapshot_lookup(struct btree_trans *trans, u32 id, |
| struct bch_snapshot *s) |
| { |
| struct btree_iter iter; |
| struct bkey_s_c k; |
| int ret; |
| |
| bch2_trans_iter_init(trans, &iter, BTREE_ID_snapshots, POS(0, id), |
| BTREE_ITER_WITH_UPDATES); |
| k = bch2_btree_iter_peek_slot(&iter); |
| ret = bkey_err(k) ?: k.k->type == KEY_TYPE_snapshot ? 0 : -ENOENT; |
| |
| if (!ret) |
| *s = *bkey_s_c_to_snapshot(k).v; |
| |
| bch2_trans_iter_exit(trans, &iter); |
| return ret; |
| } |
| |
| static int snapshot_live(struct btree_trans *trans, u32 id) |
| { |
| struct bch_snapshot v; |
| int ret; |
| |
| if (!id) |
| return 0; |
| |
| ret = snapshot_lookup(trans, id, &v); |
| if (ret == -ENOENT) |
| bch_err(trans->c, "snapshot node %u not found", id); |
| if (ret) |
| return ret; |
| |
| return !BCH_SNAPSHOT_DELETED(&v); |
| } |
| |
| static int bch2_snapshot_set_equiv(struct btree_trans *trans, struct bkey_s_c k) |
| { |
| struct bch_fs *c = trans->c; |
| unsigned i, nr_live = 0, live_idx = 0; |
| struct bkey_s_c_snapshot snap; |
| u32 id = k.k->p.offset, child[2]; |
| |
| if (k.k->type != KEY_TYPE_snapshot) |
| return 0; |
| |
| snap = bkey_s_c_to_snapshot(k); |
| |
| child[0] = le32_to_cpu(snap.v->children[0]); |
| child[1] = le32_to_cpu(snap.v->children[1]); |
| |
| for (i = 0; i < 2; i++) { |
| int ret = snapshot_live(trans, child[i]); |
| |
| if (ret < 0) |
| return ret; |
| |
| if (ret) |
| live_idx = i; |
| nr_live += ret; |
| } |
| |
| snapshot_t(c, id)->equiv = nr_live == 1 |
| ? snapshot_t(c, child[live_idx])->equiv |
| : id; |
| return 0; |
| } |
| |
| /* fsck: */ |
| static int check_snapshot(struct btree_trans *trans, |
| struct btree_iter *iter, |
| struct bkey_s_c k) |
| { |
| struct bch_fs *c = trans->c; |
| struct bkey_s_c_snapshot s; |
| struct bch_subvolume subvol; |
| struct bch_snapshot v; |
| struct printbuf buf = PRINTBUF; |
| bool should_have_subvol; |
| u32 i, id; |
| int ret = 0; |
| |
| if (k.k->type != KEY_TYPE_snapshot) |
| return 0; |
| |
| s = bkey_s_c_to_snapshot(k); |
| id = le32_to_cpu(s.v->parent); |
| if (id) { |
| ret = snapshot_lookup(trans, id, &v); |
| if (ret == -ENOENT) |
| bch_err(c, "snapshot with nonexistent parent:\n %s", |
| (bch2_bkey_val_to_text(&buf, c, s.s_c), buf.buf)); |
| if (ret) |
| goto err; |
| |
| if (le32_to_cpu(v.children[0]) != s.k->p.offset && |
| le32_to_cpu(v.children[1]) != s.k->p.offset) { |
| bch_err(c, "snapshot parent %u missing pointer to child %llu", |
| id, s.k->p.offset); |
| ret = -EINVAL; |
| goto err; |
| } |
| } |
| |
| for (i = 0; i < 2 && s.v->children[i]; i++) { |
| id = le32_to_cpu(s.v->children[i]); |
| |
| ret = snapshot_lookup(trans, id, &v); |
| if (ret == -ENOENT) |
| bch_err(c, "snapshot node %llu has nonexistent child %u", |
| s.k->p.offset, id); |
| if (ret) |
| goto err; |
| |
| if (le32_to_cpu(v.parent) != s.k->p.offset) { |
| bch_err(c, "snapshot child %u has wrong parent (got %u should be %llu)", |
| id, le32_to_cpu(v.parent), s.k->p.offset); |
| ret = -EINVAL; |
| goto err; |
| } |
| } |
| |
| should_have_subvol = BCH_SNAPSHOT_SUBVOL(s.v) && |
| !BCH_SNAPSHOT_DELETED(s.v); |
| |
| if (should_have_subvol) { |
| id = le32_to_cpu(s.v->subvol); |
| ret = bch2_subvolume_get(trans, id, 0, false, &subvol); |
| if (ret == -ENOENT) |
| bch_err(c, "snapshot points to nonexistent subvolume:\n %s", |
| (bch2_bkey_val_to_text(&buf, c, s.s_c), buf.buf)); |
| if (ret) |
| goto err; |
| |
| if (BCH_SNAPSHOT_SUBVOL(s.v) != (le32_to_cpu(subvol.snapshot) == s.k->p.offset)) { |
| bch_err(c, "snapshot node %llu has wrong BCH_SNAPSHOT_SUBVOL", |
| s.k->p.offset); |
| ret = -EINVAL; |
| goto err; |
| } |
| } else { |
| if (fsck_err_on(s.v->subvol, c, "snapshot should not point to subvol:\n %s", |
| (bch2_bkey_val_to_text(&buf, c, s.s_c), buf.buf))) { |
| struct bkey_i_snapshot *u = bch2_trans_kmalloc(trans, sizeof(*u)); |
| |
| ret = PTR_ERR_OR_ZERO(u); |
| if (ret) |
| goto err; |
| |
| bkey_reassemble(&u->k_i, s.s_c); |
| u->v.subvol = 0; |
| ret = bch2_trans_update(trans, iter, &u->k_i, 0); |
| if (ret) |
| goto err; |
| } |
| } |
| |
| if (BCH_SNAPSHOT_DELETED(s.v)) |
| set_bit(BCH_FS_HAVE_DELETED_SNAPSHOTS, &c->flags); |
| err: |
| fsck_err: |
| printbuf_exit(&buf); |
| return ret; |
| } |
| |
| int bch2_fs_check_snapshots(struct bch_fs *c) |
| { |
| struct btree_trans trans; |
| struct btree_iter iter; |
| struct bkey_s_c k; |
| int ret; |
| |
| bch2_trans_init(&trans, c, 0, 0); |
| |
| ret = for_each_btree_key_commit(&trans, iter, |
| BTREE_ID_snapshots, POS_MIN, |
| BTREE_ITER_PREFETCH, k, |
| NULL, NULL, BTREE_INSERT_LAZY_RW|BTREE_INSERT_NOFAIL, |
| check_snapshot(&trans, &iter, k)); |
| |
| if (ret) |
| bch_err(c, "error %i checking snapshots", ret); |
| |
| bch2_trans_exit(&trans); |
| return ret; |
| } |
| |
| static int check_subvol(struct btree_trans *trans, |
| struct btree_iter *iter, |
| struct bkey_s_c k) |
| { |
| struct bkey_s_c_subvolume subvol; |
| struct bch_snapshot snapshot; |
| unsigned snapid; |
| int ret; |
| |
| if (k.k->type != KEY_TYPE_subvolume) |
| return 0; |
| |
| subvol = bkey_s_c_to_subvolume(k); |
| snapid = le32_to_cpu(subvol.v->snapshot); |
| ret = snapshot_lookup(trans, snapid, &snapshot); |
| |
| if (ret == -ENOENT) |
| bch_err(trans->c, "subvolume %llu points to nonexistent snapshot %u", |
| k.k->p.offset, snapid); |
| if (ret) |
| return ret; |
| |
| if (BCH_SUBVOLUME_UNLINKED(subvol.v)) { |
| ret = bch2_subvolume_delete(trans, iter->pos.offset); |
| if (ret && !bch2_err_matches(ret, BCH_ERR_transaction_restart)) |
| bch_err(trans->c, "error deleting subvolume %llu: %s", |
| iter->pos.offset, bch2_err_str(ret)); |
| if (ret) |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| int bch2_fs_check_subvols(struct bch_fs *c) |
| { |
| struct btree_trans trans; |
| struct btree_iter iter; |
| struct bkey_s_c k; |
| int ret; |
| |
| bch2_trans_init(&trans, c, 0, 0); |
| |
| ret = for_each_btree_key_commit(&trans, iter, |
| BTREE_ID_subvolumes, POS_MIN, BTREE_ITER_PREFETCH, k, |
| NULL, NULL, BTREE_INSERT_LAZY_RW|BTREE_INSERT_NOFAIL, |
| check_subvol(&trans, &iter, k)); |
| |
| bch2_trans_exit(&trans); |
| |
| return ret; |
| } |
| |
| void bch2_fs_snapshots_exit(struct bch_fs *c) |
| { |
| genradix_free(&c->snapshots); |
| } |
| |
| int bch2_fs_snapshots_start(struct bch_fs *c) |
| { |
| struct btree_trans trans; |
| struct btree_iter iter; |
| struct bkey_s_c k; |
| int ret = 0; |
| |
| bch2_trans_init(&trans, c, 0, 0); |
| |
| for_each_btree_key2(&trans, iter, BTREE_ID_snapshots, |
| POS_MIN, 0, k, |
| bch2_mark_snapshot(&trans, BTREE_ID_snapshots, 0, bkey_s_c_null, k, 0) ?: |
| bch2_snapshot_set_equiv(&trans, k)); |
| |
| bch2_trans_exit(&trans); |
| |
| if (ret) |
| bch_err(c, "error starting snapshots: %s", bch2_err_str(ret)); |
| return ret; |
| } |
| |
| /* |
| * Mark a snapshot as deleted, for future cleanup: |
| */ |
| static int bch2_snapshot_node_set_deleted(struct btree_trans *trans, u32 id) |
| { |
| struct btree_iter iter; |
| struct bkey_i_snapshot *s; |
| int ret = 0; |
| |
| bch2_trans_iter_init(trans, &iter, BTREE_ID_snapshots, POS(0, id), |
| BTREE_ITER_INTENT); |
| s = bch2_bkey_get_mut_typed(trans, &iter, snapshot); |
| ret = PTR_ERR_OR_ZERO(s); |
| if (unlikely(ret)) { |
| bch2_fs_inconsistent_on(ret == -ENOENT, trans->c, "missing snapshot %u", id); |
| goto err; |
| } |
| |
| /* already deleted? */ |
| if (BCH_SNAPSHOT_DELETED(&s->v)) |
| goto err; |
| |
| SET_BCH_SNAPSHOT_DELETED(&s->v, true); |
| SET_BCH_SNAPSHOT_SUBVOL(&s->v, false); |
| s->v.subvol = 0; |
| |
| ret = bch2_trans_update(trans, &iter, &s->k_i, 0); |
| if (ret) |
| goto err; |
| err: |
| bch2_trans_iter_exit(trans, &iter); |
| return ret; |
| } |
| |
| static int bch2_snapshot_node_delete(struct btree_trans *trans, u32 id) |
| { |
| struct btree_iter iter, p_iter = (struct btree_iter) { NULL }; |
| struct bkey_s_c k; |
| struct bkey_s_c_snapshot s; |
| u32 parent_id; |
| unsigned i; |
| int ret = 0; |
| |
| bch2_trans_iter_init(trans, &iter, BTREE_ID_snapshots, POS(0, id), |
| BTREE_ITER_INTENT); |
| k = bch2_btree_iter_peek_slot(&iter); |
| ret = bkey_err(k); |
| if (ret) |
| goto err; |
| |
| if (k.k->type != KEY_TYPE_snapshot) { |
| bch2_fs_inconsistent(trans->c, "missing snapshot %u", id); |
| ret = -ENOENT; |
| goto err; |
| } |
| |
| s = bkey_s_c_to_snapshot(k); |
| |
| BUG_ON(!BCH_SNAPSHOT_DELETED(s.v)); |
| parent_id = le32_to_cpu(s.v->parent); |
| |
| if (parent_id) { |
| struct bkey_i_snapshot *parent; |
| |
| bch2_trans_iter_init(trans, &p_iter, BTREE_ID_snapshots, |
| POS(0, parent_id), |
| BTREE_ITER_INTENT); |
| parent = bch2_bkey_get_mut_typed(trans, &p_iter, snapshot); |
| ret = PTR_ERR_OR_ZERO(parent); |
| if (unlikely(ret)) { |
| bch2_fs_inconsistent_on(ret == -ENOENT, trans->c, "missing snapshot %u", parent_id); |
| goto err; |
| } |
| |
| for (i = 0; i < 2; i++) |
| if (le32_to_cpu(parent->v.children[i]) == id) |
| break; |
| |
| if (i == 2) |
| bch_err(trans->c, "snapshot %u missing child pointer to %u", |
| parent_id, id); |
| else |
| parent->v.children[i] = 0; |
| |
| if (le32_to_cpu(parent->v.children[0]) < |
| le32_to_cpu(parent->v.children[1])) |
| swap(parent->v.children[0], |
| parent->v.children[1]); |
| |
| ret = bch2_trans_update(trans, &p_iter, &parent->k_i, 0); |
| if (ret) |
| goto err; |
| } |
| |
| ret = bch2_btree_delete_at(trans, &iter, 0); |
| err: |
| bch2_trans_iter_exit(trans, &p_iter); |
| bch2_trans_iter_exit(trans, &iter); |
| return ret; |
| } |
| |
| int bch2_snapshot_node_create(struct btree_trans *trans, u32 parent, |
| u32 *new_snapids, |
| u32 *snapshot_subvols, |
| unsigned nr_snapids) |
| { |
| struct btree_iter iter; |
| struct bkey_i_snapshot *n; |
| struct bkey_s_c k; |
| unsigned i; |
| int ret = 0; |
| |
| bch2_trans_iter_init(trans, &iter, BTREE_ID_snapshots, |
| POS_MIN, BTREE_ITER_INTENT); |
| k = bch2_btree_iter_peek(&iter); |
| ret = bkey_err(k); |
| if (ret) |
| goto err; |
| |
| for (i = 0; i < nr_snapids; i++) { |
| k = bch2_btree_iter_prev_slot(&iter); |
| ret = bkey_err(k); |
| if (ret) |
| goto err; |
| |
| if (!k.k || !k.k->p.offset) { |
| ret = -BCH_ERR_ENOSPC_snapshot_create; |
| goto err; |
| } |
| |
| n = bch2_bkey_alloc(trans, &iter, snapshot); |
| ret = PTR_ERR_OR_ZERO(n); |
| if (ret) |
| goto err; |
| |
| n->v.flags = 0; |
| n->v.parent = cpu_to_le32(parent); |
| n->v.subvol = cpu_to_le32(snapshot_subvols[i]); |
| n->v.pad = 0; |
| SET_BCH_SNAPSHOT_SUBVOL(&n->v, true); |
| |
| ret = bch2_trans_update(trans, &iter, &n->k_i, 0) ?: |
| bch2_mark_snapshot(trans, BTREE_ID_snapshots, 0, |
| bkey_s_c_null, bkey_i_to_s_c(&n->k_i), 0); |
| if (ret) |
| goto err; |
| |
| new_snapids[i] = iter.pos.offset; |
| } |
| |
| if (parent) { |
| bch2_btree_iter_set_pos(&iter, POS(0, parent)); |
| n = bch2_bkey_get_mut_typed(trans, &iter, snapshot); |
| ret = PTR_ERR_OR_ZERO(n); |
| if (unlikely(ret)) { |
| if (ret == -ENOENT) |
| bch_err(trans->c, "snapshot %u not found", parent); |
| goto err; |
| } |
| |
| if (n->v.children[0] || n->v.children[1]) { |
| bch_err(trans->c, "Trying to add child snapshot nodes to parent that already has children"); |
| ret = -EINVAL; |
| goto err; |
| } |
| |
| n->v.children[0] = cpu_to_le32(new_snapids[0]); |
| n->v.children[1] = cpu_to_le32(new_snapids[1]); |
| n->v.subvol = 0; |
| SET_BCH_SNAPSHOT_SUBVOL(&n->v, false); |
| ret = bch2_trans_update(trans, &iter, &n->k_i, 0); |
| if (ret) |
| goto err; |
| } |
| err: |
| bch2_trans_iter_exit(trans, &iter); |
| return ret; |
| } |
| |
| static int snapshot_delete_key(struct btree_trans *trans, |
| struct btree_iter *iter, |
| struct bkey_s_c k, |
| snapshot_id_list *deleted, |
| snapshot_id_list *equiv_seen, |
| struct bpos *last_pos) |
| { |
| struct bch_fs *c = trans->c; |
| u32 equiv = snapshot_t(c, k.k->p.snapshot)->equiv; |
| |
| if (!bkey_eq(k.k->p, *last_pos)) |
| equiv_seen->nr = 0; |
| *last_pos = k.k->p; |
| |
| if (snapshot_list_has_id(deleted, k.k->p.snapshot) || |
| snapshot_list_has_id(equiv_seen, equiv)) { |
| return bch2_btree_delete_at(trans, iter, |
| BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE); |
| } else { |
| return snapshot_list_add(c, equiv_seen, equiv); |
| } |
| } |
| |
| static int bch2_delete_redundant_snapshot(struct btree_trans *trans, struct btree_iter *iter, |
| struct bkey_s_c k) |
| { |
| struct bkey_s_c_snapshot snap; |
| u32 children[2]; |
| int ret; |
| |
| if (k.k->type != KEY_TYPE_snapshot) |
| return 0; |
| |
| snap = bkey_s_c_to_snapshot(k); |
| if (BCH_SNAPSHOT_DELETED(snap.v) || |
| BCH_SNAPSHOT_SUBVOL(snap.v)) |
| return 0; |
| |
| children[0] = le32_to_cpu(snap.v->children[0]); |
| children[1] = le32_to_cpu(snap.v->children[1]); |
| |
| ret = snapshot_live(trans, children[0]) ?: |
| snapshot_live(trans, children[1]); |
| if (ret < 0) |
| return ret; |
| |
| if (!ret) |
| return bch2_snapshot_node_set_deleted(trans, k.k->p.offset); |
| return 0; |
| } |
| |
| int bch2_delete_dead_snapshots(struct bch_fs *c) |
| { |
| struct btree_trans trans; |
| struct btree_iter iter; |
| struct bkey_s_c k; |
| struct bkey_s_c_snapshot snap; |
| snapshot_id_list deleted = { 0 }; |
| u32 i, id; |
| int ret = 0; |
| |
| if (!test_bit(BCH_FS_HAVE_DELETED_SNAPSHOTS, &c->flags)) |
| return 0; |
| |
| if (!test_bit(BCH_FS_STARTED, &c->flags)) { |
| ret = bch2_fs_read_write_early(c); |
| if (ret) { |
| bch_err(c, "error deleleting dead snapshots: error going rw: %s", bch2_err_str(ret)); |
| return ret; |
| } |
| } |
| |
| bch2_trans_init(&trans, c, 0, 0); |
| |
| /* |
| * For every snapshot node: If we have no live children and it's not |
| * pointed to by a subvolume, delete it: |
| */ |
| ret = for_each_btree_key_commit(&trans, iter, BTREE_ID_snapshots, |
| POS_MIN, 0, k, |
| NULL, NULL, 0, |
| bch2_delete_redundant_snapshot(&trans, &iter, k)); |
| if (ret) { |
| bch_err(c, "error deleting redundant snapshots: %s", bch2_err_str(ret)); |
| goto err; |
| } |
| |
| for_each_btree_key2(&trans, iter, BTREE_ID_snapshots, |
| POS_MIN, 0, k, |
| bch2_snapshot_set_equiv(&trans, k)); |
| if (ret) { |
| bch_err(c, "error in bch2_snapshots_set_equiv: %s", bch2_err_str(ret)); |
| goto err; |
| } |
| |
| for_each_btree_key(&trans, iter, BTREE_ID_snapshots, |
| POS_MIN, 0, k, ret) { |
| if (k.k->type != KEY_TYPE_snapshot) |
| continue; |
| |
| snap = bkey_s_c_to_snapshot(k); |
| if (BCH_SNAPSHOT_DELETED(snap.v)) { |
| ret = snapshot_list_add(c, &deleted, k.k->p.offset); |
| if (ret) |
| break; |
| } |
| } |
| bch2_trans_iter_exit(&trans, &iter); |
| |
| if (ret) { |
| bch_err(c, "error walking snapshots: %s", bch2_err_str(ret)); |
| goto err; |
| } |
| |
| for (id = 0; id < BTREE_ID_NR; id++) { |
| struct bpos last_pos = POS_MIN; |
| snapshot_id_list equiv_seen = { 0 }; |
| |
| if (!btree_type_has_snapshots(id)) |
| continue; |
| |
| ret = for_each_btree_key_commit(&trans, iter, |
| id, POS_MIN, |
| BTREE_ITER_PREFETCH|BTREE_ITER_ALL_SNAPSHOTS, k, |
| NULL, NULL, BTREE_INSERT_NOFAIL, |
| snapshot_delete_key(&trans, &iter, k, &deleted, &equiv_seen, &last_pos)); |
| |
| darray_exit(&equiv_seen); |
| |
| if (ret) { |
| bch_err(c, "error deleting snapshot keys: %s", bch2_err_str(ret)); |
| goto err; |
| } |
| } |
| |
| for (i = 0; i < deleted.nr; i++) { |
| ret = commit_do(&trans, NULL, NULL, 0, |
| bch2_snapshot_node_delete(&trans, deleted.data[i])); |
| if (ret) { |
| bch_err(c, "error deleting snapshot %u: %s", |
| deleted.data[i], bch2_err_str(ret)); |
| goto err; |
| } |
| } |
| |
| clear_bit(BCH_FS_HAVE_DELETED_SNAPSHOTS, &c->flags); |
| err: |
| darray_exit(&deleted); |
| bch2_trans_exit(&trans); |
| return ret; |
| } |
| |
| static void bch2_delete_dead_snapshots_work(struct work_struct *work) |
| { |
| struct bch_fs *c = container_of(work, struct bch_fs, snapshot_delete_work); |
| |
| bch2_delete_dead_snapshots(c); |
| bch2_write_ref_put(c, BCH_WRITE_REF_delete_dead_snapshots); |
| } |
| |
| void bch2_delete_dead_snapshots_async(struct bch_fs *c) |
| { |
| if (bch2_write_ref_tryget(c, BCH_WRITE_REF_delete_dead_snapshots) && |
| !queue_work(c->write_ref_wq, &c->snapshot_delete_work)) |
| bch2_write_ref_put(c, BCH_WRITE_REF_delete_dead_snapshots); |
| } |
| |
| static int bch2_delete_dead_snapshots_hook(struct btree_trans *trans, |
| struct btree_trans_commit_hook *h) |
| { |
| struct bch_fs *c = trans->c; |
| |
| set_bit(BCH_FS_HAVE_DELETED_SNAPSHOTS, &c->flags); |
| |
| if (!test_bit(BCH_FS_FSCK_DONE, &c->flags)) |
| return 0; |
| |
| bch2_delete_dead_snapshots_async(c); |
| return 0; |
| } |
| |
| /* Subvolumes: */ |
| |
| int bch2_subvolume_invalid(const struct bch_fs *c, struct bkey_s_c k, |
| unsigned flags, struct printbuf *err) |
| { |
| if (bkey_lt(k.k->p, SUBVOL_POS_MIN) || |
| bkey_gt(k.k->p, SUBVOL_POS_MAX)) { |
| prt_printf(err, "invalid pos"); |
| return -BCH_ERR_invalid_bkey; |
| } |
| |
| return 0; |
| } |
| |
| 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)); |
| } |
| |
| static __always_inline int |
| bch2_subvolume_get_inlined(struct btree_trans *trans, unsigned subvol, |
| bool inconsistent_if_not_found, |
| int iter_flags, |
| struct bch_subvolume *s) |
| { |
| struct btree_iter iter; |
| struct bkey_s_c k; |
| int ret; |
| |
| bch2_trans_iter_init(trans, &iter, BTREE_ID_subvolumes, POS(0, subvol), |
| iter_flags); |
| k = bch2_btree_iter_peek_slot(&iter); |
| ret = bkey_err(k) ?: k.k->type == KEY_TYPE_subvolume ? 0 : -ENOENT; |
| |
| if (ret == -ENOENT && inconsistent_if_not_found) |
| bch2_fs_inconsistent(trans->c, "missing subvolume %u", subvol); |
| if (!ret) |
| *s = *bkey_s_c_to_subvolume(k).v; |
| |
| bch2_trans_iter_exit(trans, &iter); |
| return ret; |
| } |
| |
| int bch2_subvolume_get(struct btree_trans *trans, unsigned subvol, |
| bool inconsistent_if_not_found, |
| int iter_flags, |
| struct bch_subvolume *s) |
| { |
| return bch2_subvolume_get_inlined(trans, subvol, inconsistent_if_not_found, iter_flags, s); |
| } |
| |
| int bch2_snapshot_get_subvol(struct btree_trans *trans, u32 snapshot, |
| struct bch_subvolume *subvol) |
| { |
| struct bch_snapshot snap; |
| |
| return snapshot_lookup(trans, snapshot, &snap) ?: |
| bch2_subvolume_get(trans, le32_to_cpu(snap.subvol), true, 0, subvol); |
| } |
| |
| int bch2_subvolume_get_snapshot(struct btree_trans *trans, u32 subvol, |
| u32 *snapid) |
| { |
| struct bch_subvolume s; |
| int ret; |
| |
| ret = bch2_subvolume_get_inlined(trans, subvol, true, |
| BTREE_ITER_CACHED| |
| BTREE_ITER_WITH_UPDATES, |
| &s); |
| if (!ret) |
| *snapid = le32_to_cpu(s.snapshot); |
| return ret; |
| } |
| |
| /* |
| * Delete subvolume, mark snapshot ID as deleted, queue up snapshot |
| * deletion/cleanup: |
| */ |
| int bch2_subvolume_delete(struct btree_trans *trans, u32 subvolid) |
| { |
| struct btree_iter iter; |
| struct bkey_s_c k; |
| struct bkey_s_c_subvolume subvol; |
| struct btree_trans_commit_hook *h; |
| u32 snapid; |
| int ret = 0; |
| |
| bch2_trans_iter_init(trans, &iter, BTREE_ID_subvolumes, |
| POS(0, subvolid), |
| BTREE_ITER_CACHED| |
| BTREE_ITER_INTENT); |
| k = bch2_btree_iter_peek_slot(&iter); |
| ret = bkey_err(k); |
| if (ret) |
| goto err; |
| |
| if (k.k->type != KEY_TYPE_subvolume) { |
| bch2_fs_inconsistent(trans->c, "missing subvolume %u", subvolid); |
| ret = -EIO; |
| goto err; |
| } |
| |
| subvol = bkey_s_c_to_subvolume(k); |
| snapid = le32_to_cpu(subvol.v->snapshot); |
| |
| ret = bch2_btree_delete_at(trans, &iter, 0); |
| if (ret) |
| goto err; |
| |
| ret = bch2_snapshot_node_set_deleted(trans, snapid); |
| if (ret) |
| goto err; |
| |
| h = bch2_trans_kmalloc(trans, sizeof(*h)); |
| ret = PTR_ERR_OR_ZERO(h); |
| if (ret) |
| goto err; |
| |
| h->fn = bch2_delete_dead_snapshots_hook; |
| bch2_trans_commit_hook(trans, h); |
| err: |
| bch2_trans_iter_exit(trans, &iter); |
| return ret; |
| } |
| |
| 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); |
| snapshot_id_list s; |
| u32 *id; |
| int ret = 0; |
| |
| while (!ret) { |
| mutex_lock(&c->snapshots_unlinked_lock); |
| 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); |
| |
| for (id = s.data; id < s.data + s.nr; id++) { |
| ret = bch2_trans_do(c, NULL, NULL, BTREE_INSERT_NOFAIL, |
| bch2_subvolume_delete(&trans, *id)); |
| if (ret) { |
| bch_err(c, "error deleting subvolume %u: %s", *id, bch2_err_str(ret)); |
| break; |
| } |
| } |
| |
| darray_exit(&s); |
| } |
| |
| bch2_write_ref_put(c, BCH_WRITE_REF_snapshot_delete_pagecache); |
| } |
| |
| struct subvolume_unlink_hook { |
| struct btree_trans_commit_hook h; |
| u32 subvol; |
| }; |
| |
| 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 (!bch2_write_ref_tryget(c, BCH_WRITE_REF_snapshot_delete_pagecache)) |
| return -EROFS; |
| |
| if (!queue_work(c->write_ref_wq, &c->snapshot_wait_for_pagecache_and_delete_work)) |
| bch2_write_ref_put(c, 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; |
| |
| bch2_trans_iter_init(trans, &iter, BTREE_ID_subvolumes, |
| POS(0, subvolid), |
| BTREE_ITER_CACHED| |
| BTREE_ITER_INTENT); |
| n = bch2_bkey_get_mut_typed(trans, &iter, subvolume); |
| ret = PTR_ERR_OR_ZERO(n); |
| if (unlikely(ret)) { |
| bch2_fs_inconsistent_on(ret == -ENOENT, trans->c, "missing subvolume %u", subvolid); |
| goto err; |
| } |
| |
| SET_BCH_SUBVOLUME_UNLINKED(&n->v, true); |
| |
| ret = bch2_trans_update(trans, &iter, &n->k_i, 0); |
| if (ret) |
| goto err; |
| |
| h = bch2_trans_kmalloc(trans, sizeof(*h)); |
| ret = PTR_ERR_OR_ZERO(h); |
| if (ret) |
| goto err; |
| |
| h->h.fn = bch2_subvolume_wait_for_pagecache_and_delete_hook; |
| h->subvol = subvolid; |
| bch2_trans_commit_hook(trans, &h->h); |
| err: |
| bch2_trans_iter_exit(trans, &iter); |
| return ret; |
| } |
| |
| int bch2_subvolume_create(struct btree_trans *trans, u64 inode, |
| 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 btree_iter) { NULL }; |
| struct bkey_i_subvolume *new_subvol = NULL; |
| struct bkey_i_subvolume *src_subvol = NULL; |
| struct bkey_s_c k; |
| u32 parent = 0, new_nodes[2], snapshot_subvols[2]; |
| int ret = 0; |
| |
| for_each_btree_key(trans, dst_iter, BTREE_ID_subvolumes, SUBVOL_POS_MIN, |
| BTREE_ITER_SLOTS|BTREE_ITER_INTENT, k, ret) { |
| if (bkey_gt(k.k->p, SUBVOL_POS_MAX)) |
| break; |
| |
| /* |
| * bch2_subvolume_delete() doesn't flush the btree key cache - |
| * ideally it would but that's tricky |
| */ |
| if (bkey_deleted(k.k) && |
| !bch2_btree_key_cache_find(c, BTREE_ID_subvolumes, dst_iter.pos)) |
| goto found_slot; |
| } |
| |
| if (!ret) |
| ret = -BCH_ERR_ENOSPC_subvolume_create; |
| goto err; |
| found_slot: |
| snapshot_subvols[0] = dst_iter.pos.offset; |
| snapshot_subvols[1] = src_subvolid; |
| |
| if (src_subvolid) { |
| /* Creating a snapshot: */ |
| |
| bch2_trans_iter_init(trans, &src_iter, BTREE_ID_subvolumes, |
| POS(0, src_subvolid), |
| BTREE_ITER_CACHED| |
| BTREE_ITER_INTENT); |
| src_subvol = bch2_bkey_get_mut_typed(trans, &src_iter, subvolume); |
| ret = PTR_ERR_OR_ZERO(src_subvol); |
| if (unlikely(ret)) { |
| bch2_fs_inconsistent_on(ret == -ENOENT, trans->c, |
| "subvolume %u not found", src_subvolid); |
| 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, 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); |
| SET_BCH_SUBVOLUME_RO(&new_subvol->v, ro); |
| SET_BCH_SUBVOLUME_SNAP(&new_subvol->v, src_subvolid != 0); |
| ret = bch2_trans_update(trans, &dst_iter, &new_subvol->k_i, 0); |
| if (ret) |
| goto err; |
| |
| *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_fs_subvolumes_init(struct bch_fs *c) |
| { |
| INIT_WORK(&c->snapshot_delete_work, bch2_delete_dead_snapshots_work); |
| INIT_WORK(&c->snapshot_wait_for_pagecache_and_delete_work, |
| bch2_subvolume_wait_for_pagecache_and_delete); |
| mutex_init(&c->snapshots_unlinked_lock); |
| return 0; |
| } |