diff options
Diffstat (limited to 'fs/bcachefs/dirent.c')
-rw-r--r-- | fs/bcachefs/dirent.c | 407 |
1 files changed, 191 insertions, 216 deletions
diff --git a/fs/bcachefs/dirent.c b/fs/bcachefs/dirent.c index df9913f8967b..1442dacef0de 100644 --- a/fs/bcachefs/dirent.c +++ b/fs/bcachefs/dirent.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0 #include "bcachefs.h" #include "bkey_methods.h" @@ -12,17 +13,10 @@ unsigned bch2_dirent_name_bytes(struct bkey_s_c_dirent d) { - unsigned len = bkey_val_bytes(d.k) - sizeof(struct bch_dirent); + unsigned len = bkey_val_bytes(d.k) - + offsetof(struct bch_dirent, d_name); - while (len && !d.v->d_name[len - 1]) - --len; - - return len; -} - -static unsigned dirent_val_u64s(unsigned len) -{ - return DIV_ROUND_UP(sizeof(struct bch_dirent) + len, sizeof(u64)); + return strnlen(d.v->d_name, len); } static u64 bch2_dirent_hash(const struct bch_hash_info *info, @@ -71,8 +65,7 @@ static bool dirent_cmp_bkey(struct bkey_s_c _l, struct bkey_s_c _r) const struct bch_hash_desc bch2_dirent_hash_desc = { .btree_id = BTREE_ID_DIRENTS, - .key_type = BCH_DIRENT, - .whiteout_type = BCH_DIRENT_WHITEOUT, + .key_type = KEY_TYPE_dirent, .hash_key = dirent_hash_key, .hash_bkey = dirent_hash_bkey, .cmp_key = dirent_cmp_key, @@ -81,69 +74,53 @@ const struct bch_hash_desc bch2_dirent_hash_desc = { const char *bch2_dirent_invalid(const struct bch_fs *c, struct bkey_s_c k) { - struct bkey_s_c_dirent d; + struct bkey_s_c_dirent d = bkey_s_c_to_dirent(k); unsigned len; - switch (k.k->type) { - case BCH_DIRENT: - if (bkey_val_bytes(k.k) < sizeof(struct bch_dirent)) - return "value too small"; + if (bkey_val_bytes(k.k) < sizeof(struct bch_dirent)) + return "value too small"; - d = bkey_s_c_to_dirent(k); - len = bch2_dirent_name_bytes(d); + len = bch2_dirent_name_bytes(d); + if (!len) + return "empty name"; - if (!len) - return "empty name"; - - if (bkey_val_u64s(k.k) > dirent_val_u64s(len)) - return "value too big"; - - if (len > NAME_MAX) - return "dirent name too big"; - - if (memchr(d.v->d_name, '/', len)) - return "dirent name has invalid characters"; + /* + * older versions of bcachefs were buggy and creating dirent + * keys that were bigger than necessary: + */ + if (bkey_val_u64s(k.k) > dirent_val_u64s(len + 7)) + return "value too big"; - return NULL; - case BCH_DIRENT_WHITEOUT: - return bkey_val_bytes(k.k) != 0 - ? "value size should be zero" - : NULL; + if (len > BCH_NAME_MAX) + return "dirent name too big"; - default: - return "invalid type"; - } + return NULL; } -void bch2_dirent_to_text(struct bch_fs *c, char *buf, - size_t size, struct bkey_s_c k) +void bch2_dirent_to_text(struct printbuf *out, struct bch_fs *c, + struct bkey_s_c k) { - struct bkey_s_c_dirent d; - size_t n = 0; - - switch (k.k->type) { - case BCH_DIRENT: - d = bkey_s_c_to_dirent(k); - - n += bch_scnmemcpy(buf + n, size - n, d.v->d_name, - bch2_dirent_name_bytes(d)); - n += scnprintf(buf + n, size - n, " -> %llu", d.v->d_inum); - break; - case BCH_DIRENT_WHITEOUT: - scnprintf(buf, size, "whiteout"); - break; - } + struct bkey_s_c_dirent d = bkey_s_c_to_dirent(k); + + bch_scnmemcpy(out, d.v->d_name, + bch2_dirent_name_bytes(d)); + pr_buf(out, " -> %llu", d.v->d_inum); } -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); - dirent = kmalloc(u64s * sizeof(u64), GFP_NOFS); - if (!dirent) - return NULL; + if (name->len > BCH_NAME_MAX) + return ERR_PTR(-ENAMETOOLONG); + + BUG_ON(u64s > U8_MAX); + + dirent = bch2_trans_kmalloc(trans, u64s * sizeof(u64)); + if (IS_ERR(dirent)) + return dirent; bkey_dirent_init(&dirent->k_i); dirent->k.u64s = u64s; @@ -153,30 +130,39 @@ static struct bkey_i_dirent *dirent_create_key(u8 type, memcpy(dirent->v.d_name, name->name, name->len); memset(dirent->v.d_name + name->len, 0, bkey_val_bytes(&dirent->k) - - (sizeof(struct bch_dirent) + name->len)); + offsetof(struct bch_dirent, d_name) - + name->len); EBUG_ON(bch2_dirent_name_bytes(dirent_i_to_s_c(dirent)) != name->len); 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 (!dirent) - return -ENOMEM; + 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, @@ -192,147 +178,119 @@ 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 = -ENOMEM; - - 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 (!new_src) - goto err; - } else { - new_src = (void *) &delete; - } - - new_dst = dirent_create_key(0, dst_name, 0); - if (!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; + int 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: + 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); + + 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) { /* - * 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 + * 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_dst->k.p = src_iter.pos; - ret = bch2_btree_insert_at(c, NULL, NULL, - journal_seq, - BTREE_INSERT_ATOMIC, - BTREE_INSERT_ENTRY(&src_iter, + 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, + BTREE_INSERT_ENTRY(src_iter, &new_dst->k_i)); - goto err; + 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 = KEY_TYPE_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 = KEY_TYPE_whiteout; } - - if (need_whiteout) - new_src->k.type = BCH_DIRENT_WHITEOUT; - break; - case BCH_RENAME_OVERWRITE: - 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) { - /* - * 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: - */ - 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; } - 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, BTREE_INSERT_ENTRY(src_iter, &new_src->k_i)); + bch2_trans_update(trans, BTREE_INSERT_ENTRY(dst_iter, &new_dst->k_i)); + 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, @@ -340,66 +298,83 @@ 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, 0, 0); + + 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; } -int bch2_empty_dir(struct bch_fs *c, u64 dir_inum) +int bch2_empty_dir_trans(struct btree_trans *trans, u64 dir_inum) { - struct btree_iter iter; + struct btree_iter *iter; struct bkey_s_c k; - int ret = 0; + int ret; - for_each_btree_key(&iter, c, BTREE_ID_DIRENTS, POS(dir_inum, 0), 0, k) { + for_each_btree_key(trans, iter, BTREE_ID_DIRENTS, + POS(dir_inum, 0), 0, k, ret) { if (k.k->p.inode > dir_inum) break; - if (k.k->type == BCH_DIRENT) { + if (k.k->type == KEY_TYPE_dirent) { ret = -ENOTEMPTY; break; } } - bch2_btree_iter_unlock(&iter); + bch2_trans_iter_put(trans, iter); return ret; } +int bch2_empty_dir(struct bch_fs *c, u64 dir_inum) +{ + return bch2_trans_do(c, NULL, 0, + bch2_empty_dir_trans(&trans, dir_inum)); +} + int bch2_readdir(struct bch_fs *c, struct file *file, struct dir_context *ctx) { struct bch_inode_info *inode = file_bch_inode(file); - struct btree_iter iter; + struct btree_trans trans; + struct btree_iter *iter; struct bkey_s_c k; struct bkey_s_c_dirent dirent; unsigned len; + int ret; if (!dir_emit_dots(file, ctx)) return 0; - for_each_btree_key(&iter, c, BTREE_ID_DIRENTS, - POS(inode->v.i_ino, ctx->pos), 0, k) { - if (k.k->type != BCH_DIRENT) + bch2_trans_init(&trans, c, 0, 0); + + for_each_btree_key(&trans, iter, BTREE_ID_DIRENTS, + POS(inode->v.i_ino, ctx->pos), 0, k, ret) { + if (k.k->type != KEY_TYPE_dirent) continue; dirent = bkey_s_c_to_dirent(k); @@ -423,7 +398,7 @@ int bch2_readdir(struct bch_fs *c, struct file *file, ctx->pos = k.k->p.offset + 1; } - bch2_btree_iter_unlock(&iter); + ret = bch2_trans_exit(&trans) ?: ret; - return 0; + return ret; } |