From 63d6e9311999a3dd125ad3e0560a769e047fd7b1 Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Wed, 2 Jul 2025 13:28:55 -0400 Subject: [PATCH] bcachefs: bch2_fpunch_snapshot() Add a new version of fpunch for operating on a snapshot ID, not a subvolume - and use it for "extent past end of inode" repair. Previously, repair would try to delete everything at once, but deleting too many extents at once can overflow the btree_trans bump allocator, as well as causing other problems - the new helper properly uses bch2_extent_trim_atomic(). Reported-and-tested-by: Edoardo Codeglia Signed-off-by: Kent Overstreet --- fs/bcachefs/fsck.c | 33 ++++++--------------------------- fs/bcachefs/io_misc.c | 27 +++++++++++++++++++++++++++ fs/bcachefs/io_misc.h | 2 ++ 3 files changed, 35 insertions(+), 27 deletions(-) diff --git a/fs/bcachefs/fsck.c b/fs/bcachefs/fsck.c index dbf161e4311a..856eb2b41896 100644 --- a/fs/bcachefs/fsck.c +++ b/fs/bcachefs/fsck.c @@ -12,6 +12,7 @@ #include "fs.h" #include "fsck.h" #include "inode.h" +#include "io_misc.h" #include "keylist.h" #include "namei.h" #include "recovery_passes.h" @@ -1919,33 +1920,11 @@ static int check_extent(struct btree_trans *trans, struct btree_iter *iter, "extent type past end of inode %llu:%u, i_size %llu\n%s", i->inode.bi_inum, i->inode.bi_snapshot, i->inode.bi_size, (bch2_bkey_val_to_text(&buf, c, k), buf.buf))) { - struct bkey_i *whiteout = bch2_trans_kmalloc(trans, sizeof(*whiteout)); - ret = PTR_ERR_OR_ZERO(whiteout); - if (ret) - goto err; - - bkey_init(&whiteout->k); - whiteout->k.p = SPOS(k.k->p.inode, - last_block, - i->inode.bi_snapshot); - bch2_key_resize(&whiteout->k, - min(KEY_SIZE_MAX & (~0 << c->block_bits), - U64_MAX - whiteout->k.p.offset)); - - - /* - * Need a normal (not BTREE_ITER_all_snapshots) - * iterator, if we're deleting in a different - * snapshot and need to emit a whiteout - */ - struct btree_iter iter2; - bch2_trans_iter_init(trans, &iter2, BTREE_ID_extents, - bkey_start_pos(&whiteout->k), - BTREE_ITER_intent); - ret = bch2_btree_iter_traverse(trans, &iter2) ?: - bch2_trans_update(trans, &iter2, whiteout, - BTREE_UPDATE_internal_snapshot_node); - bch2_trans_iter_exit(trans, &iter2); + ret = bch2_fpunch_snapshot(trans, + SPOS(i->inode.bi_inum, + last_block, + i->inode.bi_snapshot), + POS(i->inode.bi_inum, U64_MAX)); if (ret) goto err; diff --git a/fs/bcachefs/io_misc.c b/fs/bcachefs/io_misc.c index bf72b1d2e2cb..07023667a475 100644 --- a/fs/bcachefs/io_misc.c +++ b/fs/bcachefs/io_misc.c @@ -135,6 +135,33 @@ err_noprint: return ret; } +/* For fsck */ +int bch2_fpunch_snapshot(struct btree_trans *trans, struct bpos start, struct bpos end) +{ + u32 restart_count = trans->restart_count; + struct bch_fs *c = trans->c; + struct disk_reservation disk_res = bch2_disk_reservation_init(c, 0); + unsigned max_sectors = KEY_SIZE_MAX & (~0 << c->block_bits); + struct bkey_i delete; + + int ret = for_each_btree_key_max_commit(trans, iter, BTREE_ID_extents, + start, end, 0, k, + &disk_res, NULL, BCH_TRANS_COMMIT_no_enospc, ({ + bkey_init(&delete.k); + delete.k.p = iter.pos; + + /* create the biggest key we can */ + bch2_key_resize(&delete.k, max_sectors); + bch2_cut_back(end, &delete); + + bch2_extent_trim_atomic(trans, &iter, &delete) ?: + bch2_trans_update(trans, &iter, &delete, 0); + })); + + bch2_disk_reservation_put(c, &disk_res); + return ret ?: trans_was_restarted(trans, restart_count); +} + /* * Returns -BCH_ERR_transacton_restart if we had to drop locks: */ diff --git a/fs/bcachefs/io_misc.h b/fs/bcachefs/io_misc.h index 9cb44a7c43c1..b93e4d4b3c0c 100644 --- a/fs/bcachefs/io_misc.h +++ b/fs/bcachefs/io_misc.h @@ -5,6 +5,8 @@ int bch2_extent_fallocate(struct btree_trans *, subvol_inum, struct btree_iter *, u64, struct bch_io_opts, s64 *, struct write_point_specifier); + +int bch2_fpunch_snapshot(struct btree_trans *, struct bpos, struct bpos); int bch2_fpunch_at(struct btree_trans *, struct btree_iter *, subvol_inum, u64, s64 *); int bch2_fpunch(struct bch_fs *c, subvol_inum, u64, u64, s64 *); -- 2.25.1