From ab2a29ccffd0e9fe62afb8bbd45e1709f9726942 Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Tue, 2 Mar 2021 18:35:30 -0500 Subject: bcachefs: Inode backpointers This patch adds two new inode fields, bi_dir and bi_dir_offset, that point back to the inode's dirent. Since we're only adding fields for a single backpointer, files that have been hardlinked won't necessarily have valid backpointers: we also add a new inode flag, BCH_INODE_BACKPTR_UNTRUSTED, that's set if an inode has ever had multiple links to it. That's ok, because we only really need this functionality for directories, which can never have multiple hardlinks - when we add subvolumes, we'll need a way to enemurate and print subvolumes, and this will let us reconstruct a path to a subvolume root given a subvolume root inode. Signed-off-by: Kent Overstreet Signed-off-by: Kent Overstreet --- fs/bcachefs/bcachefs_format.h | 9 ++++-- fs/bcachefs/dirent.c | 18 ++++++++---- fs/bcachefs/dirent.h | 6 ++-- fs/bcachefs/fs-common.c | 68 +++++++++++++++++++++++++++++++++---------- fs/bcachefs/fsck.c | 43 +++++++++++++++++++++++++++ fs/bcachefs/inode.c | 18 ++++-------- fs/bcachefs/inode.h | 3 +- 7 files changed, 125 insertions(+), 40 deletions(-) (limited to 'fs') diff --git a/fs/bcachefs/bcachefs_format.h b/fs/bcachefs/bcachefs_format.h index 2172d3cf3680..f2b5f5c06ee0 100644 --- a/fs/bcachefs/bcachefs_format.h +++ b/fs/bcachefs/bcachefs_format.h @@ -710,7 +710,9 @@ struct bch_inode_generation { x(bi_foreground_target, 16) \ x(bi_background_target, 16) \ x(bi_erasure_code, 16) \ - x(bi_fields_set, 16) + x(bi_fields_set, 16) \ + x(bi_dir, 64) \ + x(bi_dir_offset, 64) /* subset of BCH_INODE_FIELDS */ #define BCH_INODE_OPTS() \ @@ -746,6 +748,7 @@ enum { __BCH_INODE_I_SIZE_DIRTY= 5, __BCH_INODE_I_SECTORS_DIRTY= 6, __BCH_INODE_UNLINKED = 7, + __BCH_INODE_BACKPTR_UNTRUSTED = 8, /* bits 20+ reserved for packed fields below: */ }; @@ -758,6 +761,7 @@ enum { #define BCH_INODE_I_SIZE_DIRTY (1 << __BCH_INODE_I_SIZE_DIRTY) #define BCH_INODE_I_SECTORS_DIRTY (1 << __BCH_INODE_I_SECTORS_DIRTY) #define BCH_INODE_UNLINKED (1 << __BCH_INODE_UNLINKED) +#define BCH_INODE_BACKPTR_UNTRUSTED (1 << __BCH_INODE_BACKPTR_UNTRUSTED) LE32_BITMASK(INODE_STR_HASH, struct bch_inode, bi_flags, 20, 24); LE32_BITMASK(INODE_NR_FIELDS, struct bch_inode, bi_flags, 24, 31); @@ -1208,7 +1212,8 @@ enum bcachefs_metadata_version { bcachefs_metadata_version_bkey_renumber = 10, bcachefs_metadata_version_inode_btree_change = 11, bcachefs_metadata_version_snapshot = 12, - bcachefs_metadata_version_max = 13, + bcachefs_metadata_version_inode_backpointers = 13, + bcachefs_metadata_version_max = 14, }; #define bcachefs_metadata_version_current (bcachefs_metadata_version_max - 1) diff --git a/fs/bcachefs/dirent.c b/fs/bcachefs/dirent.c index 592dd80cf963..cf4ce2e7f29c 100644 --- a/fs/bcachefs/dirent.c +++ b/fs/bcachefs/dirent.c @@ -141,7 +141,7 @@ static struct bkey_i_dirent *dirent_create_key(struct btree_trans *trans, int bch2_dirent_create(struct btree_trans *trans, u64 dir_inum, const struct bch_hash_info *hash_info, u8 type, const struct qstr *name, u64 dst_inum, - int flags) + u64 *dir_offset, int flags) { struct bkey_i_dirent *dirent; int ret; @@ -151,8 +151,11 @@ int bch2_dirent_create(struct btree_trans *trans, if (ret) return ret; - return bch2_hash_set(trans, bch2_dirent_hash_desc, hash_info, - dir_inum, &dirent->k_i, flags); + ret = bch2_hash_set(trans, bch2_dirent_hash_desc, hash_info, + dir_inum, &dirent->k_i, flags); + *dir_offset = dirent->k.p.offset; + + return ret; } static void dirent_copy_target(struct bkey_i_dirent *dst, @@ -165,8 +168,8 @@ static void dirent_copy_target(struct bkey_i_dirent *dst, int bch2_dirent_rename(struct btree_trans *trans, u64 src_dir, struct bch_hash_info *src_hash, u64 dst_dir, struct bch_hash_info *dst_hash, - const struct qstr *src_name, u64 *src_inum, - const struct qstr *dst_name, u64 *dst_inum, + const struct qstr *src_name, u64 *src_inum, u64 *src_offset, + const struct qstr *dst_name, u64 *dst_inum, u64 *dst_offset, enum bch_rename_mode mode) { struct btree_iter *src_iter = NULL, *dst_iter = NULL; @@ -255,7 +258,7 @@ int bch2_dirent_rename(struct btree_trans *trans, new_dst->k.p = src_iter->pos; bch2_trans_update(trans, src_iter, &new_dst->k_i, 0); - goto out; + goto out_set_offset; } else { /* If we're overwriting, we can't insert new_dst * at a different slot because it has to @@ -278,6 +281,9 @@ int bch2_dirent_rename(struct btree_trans *trans, bch2_trans_update(trans, src_iter, &new_src->k_i, 0); bch2_trans_update(trans, dst_iter, &new_dst->k_i, 0); +out_set_offset: + *src_offset = new_src->k.p.offset; + *dst_offset = new_dst->k.p.offset; out: bch2_trans_iter_put(trans, src_iter); bch2_trans_iter_put(trans, dst_iter); diff --git a/fs/bcachefs/dirent.h b/fs/bcachefs/dirent.h index 34769371dd13..e1d8ce377d43 100644 --- a/fs/bcachefs/dirent.h +++ b/fs/bcachefs/dirent.h @@ -31,7 +31,7 @@ static inline unsigned dirent_val_u64s(unsigned len) int bch2_dirent_create(struct btree_trans *, u64, const struct bch_hash_info *, u8, - const struct qstr *, u64, int); + const struct qstr *, u64, u64 *, int); int bch2_dirent_delete_at(struct btree_trans *, const struct bch_hash_info *, @@ -46,8 +46,8 @@ enum bch_rename_mode { int bch2_dirent_rename(struct btree_trans *, u64, struct bch_hash_info *, u64, struct bch_hash_info *, - const struct qstr *, u64 *, - const struct qstr *, u64 *, + const struct qstr *, u64 *, u64 *, + const struct qstr *, u64 *, u64 *, enum bch_rename_mode); struct btree_iter * diff --git a/fs/bcachefs/fs-common.c b/fs/bcachefs/fs-common.c index 503ce1920f39..83c2168ce480 100644 --- a/fs/bcachefs/fs-common.c +++ b/fs/bcachefs/fs-common.c @@ -20,8 +20,10 @@ int bch2_create_trans(struct btree_trans *trans, u64 dir_inum, { struct bch_fs *c = trans->c; struct btree_iter *dir_iter = NULL; + struct btree_iter *inode_iter = NULL; struct bch_hash_info hash = bch2_hash_info_init(c, new_inode); - u64 now = bch2_current_time(trans->c); + u64 now = bch2_current_time(c); + u64 dir_offset = 0; int ret; dir_iter = bch2_inode_peek(trans, dir_u, dir_inum, BTREE_ITER_INTENT); @@ -34,7 +36,8 @@ int bch2_create_trans(struct btree_trans *trans, u64 dir_inum, if (!name) new_inode->bi_flags |= BCH_INODE_UNLINKED; - ret = bch2_inode_create(trans, new_inode); + inode_iter = bch2_inode_create(trans, new_inode); + ret = PTR_ERR_OR_ZERO(inode_iter); if (ret) goto err; @@ -66,11 +69,20 @@ int bch2_create_trans(struct btree_trans *trans, u64 dir_inum, ret = bch2_dirent_create(trans, dir_inum, &dir_hash, mode_to_type(new_inode->bi_mode), name, new_inode->bi_inum, + &dir_offset, BCH_HASH_SET_MUST_CREATE); if (ret) goto err; } + + if (c->sb.version >= bcachefs_metadata_version_inode_backpointers) { + new_inode->bi_dir = dir_u->bi_inum; + new_inode->bi_dir_offset = dir_offset; + } + + ret = bch2_inode_write(trans, inode_iter, new_inode); err: + bch2_trans_iter_put(trans, inode_iter); bch2_trans_iter_put(trans, dir_iter); return ret; } @@ -79,9 +91,11 @@ int bch2_link_trans(struct btree_trans *trans, u64 dir_inum, u64 inum, struct bch_inode_unpacked *dir_u, struct bch_inode_unpacked *inode_u, const struct qstr *name) { + struct bch_fs *c = trans->c; struct btree_iter *dir_iter = NULL, *inode_iter = NULL; struct bch_hash_info dir_hash; - u64 now = bch2_current_time(trans->c); + u64 now = bch2_current_time(c); + u64 dir_offset = 0; int ret; inode_iter = bch2_inode_peek(trans, inode_u, inum, BTREE_ITER_INTENT); @@ -92,6 +106,8 @@ int bch2_link_trans(struct btree_trans *trans, u64 dir_inum, inode_u->bi_ctime = now; bch2_inode_nlink_inc(inode_u); + inode_u->bi_flags |= BCH_INODE_BACKPTR_UNTRUSTED; + dir_iter = bch2_inode_peek(trans, dir_u, dir_inum, 0); ret = PTR_ERR_OR_ZERO(dir_iter); if (ret) @@ -99,12 +115,21 @@ int bch2_link_trans(struct btree_trans *trans, u64 dir_inum, dir_u->bi_mtime = dir_u->bi_ctime = now; - dir_hash = bch2_hash_info_init(trans->c, dir_u); + dir_hash = bch2_hash_info_init(c, dir_u); - ret = bch2_dirent_create(trans, dir_inum, &dir_hash, - mode_to_type(inode_u->bi_mode), - name, inum, BCH_HASH_SET_MUST_CREATE) ?: - bch2_inode_write(trans, dir_iter, dir_u) ?: + ret = bch2_dirent_create(trans, dir_inum, &dir_hash, + mode_to_type(inode_u->bi_mode), + name, inum, &dir_offset, + BCH_HASH_SET_MUST_CREATE); + if (ret) + goto err; + + if (c->sb.version >= bcachefs_metadata_version_inode_backpointers) { + inode_u->bi_dir = dir_inum; + inode_u->bi_dir_offset = dir_offset; + } + + ret = bch2_inode_write(trans, dir_iter, dir_u) ?: bch2_inode_write(trans, inode_iter, inode_u); err: bch2_trans_iter_put(trans, dir_iter); @@ -117,10 +142,11 @@ int bch2_unlink_trans(struct btree_trans *trans, struct bch_inode_unpacked *inode_u, const struct qstr *name) { + struct bch_fs *c = trans->c; struct btree_iter *dir_iter = NULL, *dirent_iter = NULL, *inode_iter = NULL; struct bch_hash_info dir_hash; - u64 inum, now = bch2_current_time(trans->c); + u64 inum, now = bch2_current_time(c); struct bkey_s_c k; int ret; @@ -129,7 +155,7 @@ int bch2_unlink_trans(struct btree_trans *trans, if (ret) goto err; - dir_hash = bch2_hash_info_init(trans->c, dir_u); + dir_hash = bch2_hash_info_init(c, dir_u); dirent_iter = __bch2_dirent_lookup_trans(trans, dir_inum, &dir_hash, name, BTREE_ITER_INTENT); @@ -195,10 +221,12 @@ int bch2_rename_trans(struct btree_trans *trans, const struct qstr *dst_name, enum bch_rename_mode mode) { + struct bch_fs *c = trans->c; struct btree_iter *src_dir_iter = NULL, *dst_dir_iter = NULL; struct btree_iter *src_inode_iter = NULL, *dst_inode_iter = NULL; struct bch_hash_info src_hash, dst_hash; - u64 src_inode, dst_inode, now = bch2_current_time(trans->c); + u64 src_inode, src_offset, dst_inode, dst_offset; + u64 now = bch2_current_time(c); int ret; src_dir_iter = bch2_inode_peek(trans, src_dir_u, src_dir, @@ -207,7 +235,7 @@ int bch2_rename_trans(struct btree_trans *trans, if (ret) goto err; - src_hash = bch2_hash_info_init(trans->c, src_dir_u); + src_hash = bch2_hash_info_init(c, src_dir_u); if (dst_dir != src_dir) { dst_dir_iter = bch2_inode_peek(trans, dst_dir_u, dst_dir, @@ -216,7 +244,7 @@ int bch2_rename_trans(struct btree_trans *trans, if (ret) goto err; - dst_hash = bch2_hash_info_init(trans->c, dst_dir_u); + dst_hash = bch2_hash_info_init(c, dst_dir_u); } else { dst_dir_u = src_dir_u; dst_hash = src_hash; @@ -225,8 +253,8 @@ int bch2_rename_trans(struct btree_trans *trans, ret = bch2_dirent_rename(trans, src_dir, &src_hash, dst_dir, &dst_hash, - src_name, &src_inode, - dst_name, &dst_inode, + src_name, &src_inode, &src_offset, + dst_name, &dst_inode, &dst_offset, mode); if (ret) goto err; @@ -245,6 +273,16 @@ int bch2_rename_trans(struct btree_trans *trans, goto err; } + if (c->sb.version >= bcachefs_metadata_version_inode_backpointers) { + src_inode_u->bi_dir = dst_dir_u->bi_inum; + src_inode_u->bi_dir_offset = dst_offset; + + if (mode == BCH_RENAME_EXCHANGE) { + dst_inode_u->bi_dir = src_dir_u->bi_inum; + dst_inode_u->bi_dir_offset = src_offset; + } + } + if (mode == BCH_RENAME_OVERWRITE) { if (S_ISDIR(src_inode_u->bi_mode) != S_ISDIR(dst_inode_u->bi_mode)) { diff --git a/fs/bcachefs/fsck.c b/fs/bcachefs/fsck.c index a3acae0ddfa9..d65b3e100f78 100644 --- a/fs/bcachefs/fsck.c +++ b/fs/bcachefs/fsck.c @@ -675,6 +675,39 @@ retry: continue; } + if (!target.bi_nlink && + !(target.bi_flags & BCH_INODE_BACKPTR_UNTRUSTED) && + (target.bi_dir != k.k->p.inode || + target.bi_dir_offset != k.k->p.offset) && + (fsck_err_on(c->sb.version >= bcachefs_metadata_version_inode_backpointers, c, + "inode %llu has wrong backpointer:\n" + "got %llu:%llu\n" + "should be %llu:%llu", + d_inum, + target.bi_dir, + target.bi_dir_offset, + k.k->p.inode, + k.k->p.offset) || + c->opts.version_upgrade)) { + struct bkey_inode_buf p; + + target.bi_dir = k.k->p.inode; + target.bi_dir_offset = k.k->p.offset; + bch2_trans_unlock(&trans); + + bch2_inode_pack(c, &p, &target); + + ret = bch2_btree_insert(c, BTREE_ID_inodes, + &p.inode.k_i, NULL, NULL, + BTREE_INSERT_NOFAIL| + BTREE_INSERT_LAZY_RW); + if (ret) { + bch_err(c, "error in fsck: error %i updating inode", ret); + goto err; + } + continue; + } + if (fsck_err_on(have_target && d.v->d_type != mode_to_type(target.bi_mode), c, @@ -1314,6 +1347,16 @@ static int check_inode(struct btree_trans *trans, do_update = true; } + if (!S_ISDIR(u.bi_mode) && + u.bi_nlink && + !(u.bi_flags & BCH_INODE_BACKPTR_UNTRUSTED) && + (fsck_err_on(c->sb.version >= bcachefs_metadata_version_inode_backpointers, c, + "inode missing BCH_INODE_BACKPTR_UNTRUSTED flags") || + c->opts.version_upgrade)) { + u.bi_flags |= BCH_INODE_BACKPTR_UNTRUSTED; + do_update = true; + } + if (do_update) { struct bkey_inode_buf p; diff --git a/fs/bcachefs/inode.c b/fs/bcachefs/inode.c index 7044ab73831c..b72b3578bbe2 100644 --- a/fs/bcachefs/inode.c +++ b/fs/bcachefs/inode.c @@ -470,11 +470,10 @@ static inline u32 bkey_generation(struct bkey_s_c k) } } -int bch2_inode_create(struct btree_trans *trans, - struct bch_inode_unpacked *inode_u) +struct btree_iter *bch2_inode_create(struct btree_trans *trans, + struct bch_inode_unpacked *inode_u) { struct bch_fs *c = trans->c; - struct bkey_inode_buf *inode_p; struct btree_iter *iter = NULL; struct bkey_s_c k; u64 min, max, start, *hint; @@ -494,10 +493,6 @@ int bch2_inode_create(struct btree_trans *trans, if (start >= max || start < min) start = min; - - inode_p = bch2_trans_kmalloc(trans, sizeof(*inode_p)); - if (IS_ERR(inode_p)) - return PTR_ERR(inode_p); again: for_each_btree_key(trans, iter, BTREE_ID_inodes, POS(0, start), BTREE_ITER_SLOTS|BTREE_ITER_INTENT, k, ret) { @@ -521,7 +516,7 @@ again: bch2_trans_iter_put(trans, iter); if (ret) - return ret; + return ERR_PTR(ret); if (start != min) { /* Retry from start */ @@ -529,15 +524,12 @@ again: goto again; } - return -ENOSPC; + return ERR_PTR(-ENOSPC); found_slot: *hint = k.k->p.offset; inode_u->bi_inum = k.k->p.offset; inode_u->bi_generation = bkey_generation(k); - - ret = bch2_inode_write(trans, iter, inode_u); - bch2_trans_iter_put(trans, iter); - return ret; + return iter; } int bch2_inode_rm(struct bch_fs *c, u64 inode_nr, bool cached) diff --git a/fs/bcachefs/inode.h b/fs/bcachefs/inode.h index 1caf036ae928..6bad6dfb7989 100644 --- a/fs/bcachefs/inode.h +++ b/fs/bcachefs/inode.h @@ -69,7 +69,8 @@ void bch2_inode_init(struct bch_fs *, struct bch_inode_unpacked *, uid_t, gid_t, umode_t, dev_t, struct bch_inode_unpacked *); -int bch2_inode_create(struct btree_trans *, struct bch_inode_unpacked *); +struct btree_iter *bch2_inode_create(struct btree_trans *, + struct bch_inode_unpacked *); int bch2_inode_rm(struct bch_fs *, u64, bool); -- cgit v1.2.3