diff options
Diffstat (limited to 'libbcachefs/dirent.c')
-rw-r--r-- | libbcachefs/dirent.c | 284 |
1 files changed, 132 insertions, 152 deletions
diff --git a/libbcachefs/dirent.c b/libbcachefs/dirent.c index d3dd3eb7..d979ae0e 100644 --- a/libbcachefs/dirent.c +++ b/libbcachefs/dirent.c @@ -141,8 +141,8 @@ void bch2_dirent_to_text(struct bch_fs *c, char *buf, } } -static struct bkey_i_dirent *dirent_create_key(u8 type, - const struct qstr *name, u64 dst) +static struct bkey_i_dirent *dirent_create_key(struct btree_trans *trans, + u8 type, const struct qstr *name, u64 dst) { struct bkey_i_dirent *dirent; unsigned u64s = BKEY_U64s + dirent_val_u64s(name->len); @@ -152,9 +152,9 @@ static struct bkey_i_dirent *dirent_create_key(u8 type, BUG_ON(u64s > U8_MAX); - dirent = kmalloc(u64s * sizeof(u64), GFP_NOFS); - if (!dirent) - return ERR_PTR(-ENOMEM); + dirent = bch2_trans_kmalloc(trans, u64s * sizeof(u64)); + if (IS_ERR(dirent)) + return dirent; bkey_dirent_init(&dirent->k_i); dirent->k.u64s = u64s; @@ -172,23 +172,31 @@ static struct bkey_i_dirent *dirent_create_key(u8 type, return dirent; } -int bch2_dirent_create(struct bch_fs *c, u64 dir_inum, - const struct bch_hash_info *hash_info, - u8 type, const struct qstr *name, u64 dst_inum, - u64 *journal_seq, int flags) +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) { struct bkey_i_dirent *dirent; int ret; - dirent = dirent_create_key(type, name, dst_inum); - if (IS_ERR(dirent)) - return PTR_ERR(dirent); + dirent = dirent_create_key(trans, type, name, dst_inum); + ret = PTR_ERR_OR_ZERO(dirent); + if (ret) + return ret; - ret = bch2_hash_set(bch2_dirent_hash_desc, hash_info, c, dir_inum, - journal_seq, &dirent->k_i, flags); - kfree(dirent); + return __bch2_hash_set(trans, bch2_dirent_hash_desc, hash_info, + dir_inum, &dirent->k_i, flags); +} - return ret; +int bch2_dirent_create(struct bch_fs *c, u64 dir_inum, + const struct bch_hash_info *hash_info, + u8 type, const struct qstr *name, u64 dst_inum, + u64 *journal_seq, int flags) +{ + return bch2_trans_do(c, journal_seq, flags, + __bch2_dirent_create(&trans, dir_inum, hash_info, + type, name, dst_inum, flags)); } static void dirent_copy_target(struct bkey_i_dirent *dst, @@ -204,151 +212,117 @@ static struct bpos bch2_dirent_pos(struct bch_inode_info *inode, return POS(inode->v.i_ino, bch2_dirent_hash(&inode->ei_str_hash, name)); } -int bch2_dirent_rename(struct bch_fs *c, +int bch2_dirent_rename(struct btree_trans *trans, struct bch_inode_info *src_dir, const struct qstr *src_name, struct bch_inode_info *dst_dir, const struct qstr *dst_name, - u64 *journal_seq, enum bch_rename_mode mode) + enum bch_rename_mode mode) { - struct btree_iter src_iter, dst_iter, whiteout_iter; + struct btree_iter *src_iter, *dst_iter; struct bkey_s_c old_src, old_dst; - struct bkey delete; struct bkey_i_dirent *new_src = NULL, *new_dst = NULL; - struct bpos src_pos = bch2_dirent_pos(src_dir, src_name); struct bpos dst_pos = bch2_dirent_pos(dst_dir, dst_name); - bool need_whiteout; int ret; - bch2_btree_iter_init(&src_iter, c, BTREE_ID_DIRENTS, src_pos, - BTREE_ITER_SLOTS|BTREE_ITER_INTENT); - bch2_btree_iter_init(&dst_iter, c, BTREE_ID_DIRENTS, dst_pos, - BTREE_ITER_SLOTS|BTREE_ITER_INTENT); - bch2_btree_iter_link(&src_iter, &dst_iter); - - bch2_btree_iter_init(&whiteout_iter, c, BTREE_ID_DIRENTS, src_pos, - BTREE_ITER_SLOTS); - bch2_btree_iter_link(&src_iter, &whiteout_iter); - - if (mode == BCH_RENAME_EXCHANGE) { - new_src = dirent_create_key(0, src_name, 0); - if (IS_ERR(new_src)) { - ret = PTR_ERR(new_src); - goto err; - } - } else { - new_src = (void *) &delete; - } - - new_dst = dirent_create_key(0, dst_name, 0); - if (IS_ERR(new_dst)) { - ret = PTR_ERR(new_dst); - goto err; - } -retry: - /* - * Note that on -EINTR/dropped locks we're not restarting the lookup - * from the original hashed position (like we do when creating dirents, - * in bch_hash_set) - we never move existing dirents to different slot: - */ - old_src = bch2_hash_lookup_at(bch2_dirent_hash_desc, - &src_dir->ei_str_hash, - &src_iter, src_name); - if ((ret = btree_iter_err(old_src))) - goto err; - - ret = bch2_hash_needs_whiteout(bch2_dirent_hash_desc, - &src_dir->ei_str_hash, - &whiteout_iter, &src_iter); - if (ret < 0) - goto err; - need_whiteout = ret; - /* + * Lookup dst: + * * Note that in BCH_RENAME mode, we're _not_ checking if * the target already exists - we're relying on the VFS * to do that check for us for correctness: */ - old_dst = mode == BCH_RENAME - ? bch2_hash_hole_at(bch2_dirent_hash_desc, &dst_iter) - : bch2_hash_lookup_at(bch2_dirent_hash_desc, - &dst_dir->ei_str_hash, - &dst_iter, dst_name); - if ((ret = btree_iter_err(old_dst))) - goto err; - - switch (mode) { - case BCH_RENAME: - bkey_init(&new_src->k); - dirent_copy_target(new_dst, bkey_s_c_to_dirent(old_src)); - - if (bkey_cmp(dst_pos, src_iter.pos) <= 0 && - bkey_cmp(src_iter.pos, dst_iter.pos) < 0) { - /* - * If we couldn't insert new_dst at its hashed - * position (dst_pos) due to a hash collision, - * and we're going to be deleting in - * between the hashed position and first empty - * slot we found - just overwrite the pos we - * were going to delete: - * - * Note: this is a correctness issue, in this - * situation bch2_hash_needs_whiteout() could - * return false when the whiteout would have - * been needed if we inserted at the pos - * __dirent_find_hole() found - */ - new_dst->k.p = src_iter.pos; - ret = bch2_btree_insert_at(c, NULL, NULL, - journal_seq, - BTREE_INSERT_ATOMIC, - BTREE_INSERT_ENTRY(&src_iter, - &new_dst->k_i)); - goto err; - } + dst_iter = mode == BCH_RENAME + ? bch2_hash_hole(trans, bch2_dirent_hash_desc, + &dst_dir->ei_str_hash, + dst_dir->v.i_ino, dst_name) + : bch2_hash_lookup(trans, bch2_dirent_hash_desc, + &dst_dir->ei_str_hash, + dst_dir->v.i_ino, dst_name, + BTREE_ITER_INTENT); + if (IS_ERR(dst_iter)) + return PTR_ERR(dst_iter); + old_dst = bch2_btree_iter_peek_slot(dst_iter); + + /* Lookup src: */ + src_iter = bch2_hash_lookup(trans, bch2_dirent_hash_desc, + &src_dir->ei_str_hash, + src_dir->v.i_ino, src_name, + BTREE_ITER_INTENT); + if (IS_ERR(src_iter)) + return PTR_ERR(src_iter); + old_src = bch2_btree_iter_peek_slot(src_iter); + + /* Create new dst key: */ + new_dst = dirent_create_key(trans, 0, dst_name, 0); + if (IS_ERR(new_dst)) + return PTR_ERR(new_dst); + + dirent_copy_target(new_dst, bkey_s_c_to_dirent(old_src)); + new_dst->k.p = dst_iter->pos; + + /* Create new src key: */ + if (mode == BCH_RENAME_EXCHANGE) { + new_src = dirent_create_key(trans, 0, src_name, 0); + if (IS_ERR(new_src)) + return PTR_ERR(new_src); - if (need_whiteout) - new_src->k.type = BCH_DIRENT_WHITEOUT; - break; - case BCH_RENAME_OVERWRITE: + dirent_copy_target(new_src, bkey_s_c_to_dirent(old_dst)); + new_src->k.p = src_iter->pos; + } else { + new_src = bch2_trans_kmalloc(trans, sizeof(struct bkey_i)); + if (IS_ERR(new_src)) + return PTR_ERR(new_src); bkey_init(&new_src->k); - dirent_copy_target(new_dst, bkey_s_c_to_dirent(old_src)); + new_src->k.p = src_iter->pos; - if (bkey_cmp(dst_pos, src_iter.pos) <= 0 && - bkey_cmp(src_iter.pos, dst_iter.pos) < 0) { + if (bkey_cmp(dst_pos, src_iter->pos) <= 0 && + bkey_cmp(src_iter->pos, dst_iter->pos) < 0) { /* - * Same case described above - - * bch_hash_needs_whiteout could spuriously - * return false, but we have to insert at - * dst_iter.pos because we're overwriting - * another dirent: + * We have a hash collision for the new dst key, + * and new_src - the key we're deleting - is between + * new_dst's hashed slot and the slot we're going to be + * inserting it into - oops. This will break the hash + * table if we don't deal with it: */ - new_src->k.type = BCH_DIRENT_WHITEOUT; - } else if (need_whiteout) - new_src->k.type = BCH_DIRENT_WHITEOUT; - break; - case BCH_RENAME_EXCHANGE: - dirent_copy_target(new_src, bkey_s_c_to_dirent(old_dst)); - dirent_copy_target(new_dst, bkey_s_c_to_dirent(old_src)); - break; + if (mode == BCH_RENAME) { + /* + * If we're not overwriting, we can just insert + * new_dst at the src position: + */ + new_dst->k.p = src_iter->pos; + bch2_trans_update(trans, src_iter, &new_dst->k_i, 0); + return 0; + } else { + /* If we're overwriting, we can't insert new_dst + * at a different slot because it has to + * overwrite old_dst - just make sure to use a + * whiteout when deleting src: + */ + new_src->k.type = BCH_DIRENT_WHITEOUT; + } + } else { + /* Check if we need a whiteout to delete src: */ + ret = bch2_hash_needs_whiteout(trans, bch2_dirent_hash_desc, + &src_dir->ei_str_hash, + src_iter); + if (ret < 0) + return ret; + + if (ret) + new_src->k.type = BCH_DIRENT_WHITEOUT; + } } - new_src->k.p = src_iter.pos; - new_dst->k.p = dst_iter.pos; - ret = bch2_btree_insert_at(c, NULL, NULL, journal_seq, - BTREE_INSERT_ATOMIC, - BTREE_INSERT_ENTRY(&src_iter, &new_src->k_i), - BTREE_INSERT_ENTRY(&dst_iter, &new_dst->k_i)); -err: - if (ret == -EINTR) - goto retry; - - bch2_btree_iter_unlock(&whiteout_iter); - bch2_btree_iter_unlock(&dst_iter); - bch2_btree_iter_unlock(&src_iter); - - if (new_src != (void *) &delete) - kfree(new_src); - kfree(new_dst); - return ret; + bch2_trans_update(trans, src_iter, &new_src->k_i, 0); + bch2_trans_update(trans, dst_iter, &new_dst->k_i, 0); + return 0; +} + +int __bch2_dirent_delete(struct btree_trans *trans, u64 dir_inum, + const struct bch_hash_info *hash_info, + const struct qstr *name) +{ + return bch2_hash_delete(trans, bch2_dirent_hash_desc, hash_info, + dir_inum, name); } int bch2_dirent_delete(struct bch_fs *c, u64 dir_inum, @@ -356,28 +330,34 @@ int bch2_dirent_delete(struct bch_fs *c, u64 dir_inum, const struct qstr *name, u64 *journal_seq) { - return bch2_hash_delete(bch2_dirent_hash_desc, hash_info, - c, dir_inum, journal_seq, name); + return bch2_trans_do(c, journal_seq, + BTREE_INSERT_ATOMIC| + BTREE_INSERT_NOFAIL, + __bch2_dirent_delete(&trans, dir_inum, hash_info, name)); } u64 bch2_dirent_lookup(struct bch_fs *c, u64 dir_inum, const struct bch_hash_info *hash_info, const struct qstr *name) { - struct btree_iter iter; + struct btree_trans trans; + struct btree_iter *iter; struct bkey_s_c k; - u64 inum; + u64 inum = 0; - k = bch2_hash_lookup(bch2_dirent_hash_desc, hash_info, c, - dir_inum, &iter, name); - if (IS_ERR(k.k)) { - bch2_btree_iter_unlock(&iter); - return 0; + bch2_trans_init(&trans, c); + + iter = bch2_hash_lookup(&trans, bch2_dirent_hash_desc, + hash_info, dir_inum, name, 0); + if (IS_ERR(iter)) { + BUG_ON(PTR_ERR(iter) == -EINTR); + goto out; } + k = bch2_btree_iter_peek_slot(iter); inum = le64_to_cpu(bkey_s_c_to_dirent(k).v->d_inum); - bch2_btree_iter_unlock(&iter); - +out: + bch2_trans_exit(&trans); return inum; } |