[PATCH 16/18] bcachefs: Kill dirent_occupied_size()

[Kent Overstreet <kent.overstreet@linux.dev>]

With the upcoming patches for casefolding, we really need to use the
size of the dirent key itself - which is cleaner, anyways.

The size of the dirent is no longer just a function of the length of the
name, it'll be different depending on whether the directory has
casefolding enabled - which means the accounting in rename() has to
change a bit.

Cc: Hongbo Li <lihongbo22@huawei.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
---
 fs/bcachefs/dirent.c    | 15 +++++++++++++--
 fs/bcachefs/dirent.h    | 11 +++--------
 fs/bcachefs/fs-common.c | 42 ++++++++++++++++++++++-------------------
 fs/bcachefs/fsck.c      |  5 +----
 4 files changed, 40 insertions(+), 33 deletions(-)

diff --git a/fs/bcachefs/dirent.c b/fs/bcachefs/dirent.c
index 600eee936f13..27737aaa03a6 100644
--- a/fs/bcachefs/dirent.c
+++ b/fs/bcachefs/dirent.c
@@ -233,6 +233,7 @@ int bch2_dirent_create(struct btree_trans *trans, subvol_inum dir,
 		       const struct bch_hash_info *hash_info,
 		       u8 type, const struct qstr *name, u64 dst_inum,
 		       u64 *dir_offset,
+		       u64 *i_size,
 		       enum btree_iter_update_trigger_flags flags)
 {
 	struct bkey_i_dirent *dirent;
@@ -243,6 +244,8 @@ int bch2_dirent_create(struct btree_trans *trans, subvol_inum dir,
 	if (ret)
 		return ret;
 
+	*i_size += bkey_bytes(&dirent->k);
+
 	ret = bch2_hash_set(trans, bch2_dirent_hash_desc, hash_info,
 			    dir, &dirent->k_i, flags);
 	*dir_offset = dirent->k.p.offset;
@@ -275,8 +278,8 @@ int bch2_dirent_read_target(struct btree_trans *trans, subvol_inum dir,
 }
 
 int bch2_dirent_rename(struct btree_trans *trans,
-		subvol_inum src_dir, struct bch_hash_info *src_hash,
-		subvol_inum dst_dir, struct bch_hash_info *dst_hash,
+		subvol_inum src_dir, struct bch_hash_info *src_hash, u64 *src_dir_i_size,
+		subvol_inum dst_dir, struct bch_hash_info *dst_hash, u64 *dst_dir_i_size,
 		const struct qstr *src_name, subvol_inum *src_inum, u64 *src_offset,
 		const struct qstr *dst_name, subvol_inum *dst_inum, u64 *dst_offset,
 		enum bch_rename_mode mode)
@@ -406,6 +409,14 @@ int bch2_dirent_rename(struct btree_trans *trans,
 	    new_src->v.d_type == DT_SUBVOL)
 		new_src->v.d_parent_subvol = cpu_to_le32(src_dir.subvol);
 
+	if (old_dst.k)
+		*dst_dir_i_size -= bkey_bytes(old_dst.k);
+	*src_dir_i_size -= bkey_bytes(old_src.k);
+
+	if (mode == BCH_RENAME_EXCHANGE)
+		*src_dir_i_size += bkey_bytes(&new_src->k);
+	*dst_dir_i_size += bkey_bytes(&new_dst->k);
+
 	ret = bch2_trans_update(trans, &dst_iter, &new_dst->k_i, 0);
 	if (ret)
 		goto out;
diff --git a/fs/bcachefs/dirent.h b/fs/bcachefs/dirent.h
index a633f83c1ac7..37f01c1a3f7f 100644
--- a/fs/bcachefs/dirent.h
+++ b/fs/bcachefs/dirent.h
@@ -31,11 +31,6 @@ static inline unsigned dirent_val_u64s(unsigned len)
 			    sizeof(u64));
 }
 
-static inline unsigned int dirent_occupied_size(const struct qstr *name)
-{
-	return (BKEY_U64s + dirent_val_u64s(name->len)) * sizeof(u64);
-}
-
 int bch2_dirent_read_target(struct btree_trans *, subvol_inum,
 			    struct bkey_s_c_dirent, subvol_inum *);
 
@@ -52,7 +47,7 @@ int bch2_dirent_create_snapshot(struct btree_trans *, u32, u64, u32,
 			enum btree_iter_update_trigger_flags);
 int bch2_dirent_create(struct btree_trans *, subvol_inum,
 		       const struct bch_hash_info *, u8,
-		       const struct qstr *, u64, u64 *,
+		       const struct qstr *, u64, u64 *, u64 *,
 		       enum btree_iter_update_trigger_flags);
 
 static inline unsigned vfs_d_type(unsigned type)
@@ -67,8 +62,8 @@ enum bch_rename_mode {
 };
 
 int bch2_dirent_rename(struct btree_trans *,
-		       subvol_inum, struct bch_hash_info *,
-		       subvol_inum, struct bch_hash_info *,
+		       subvol_inum, struct bch_hash_info *, u64 *,
+		       subvol_inum, struct bch_hash_info *, u64 *,
 		       const struct qstr *, subvol_inum *, u64 *,
 		       const struct qstr *, subvol_inum *, u64 *,
 		       enum bch_rename_mode);
diff --git a/fs/bcachefs/fs-common.c b/fs/bcachefs/fs-common.c
index d70d9f634cea..c8afd312e601 100644
--- a/fs/bcachefs/fs-common.c
+++ b/fs/bcachefs/fs-common.c
@@ -42,11 +42,14 @@ int bch2_create_trans(struct btree_trans *trans,
 	if (ret)
 		goto err;
 
-	ret = bch2_inode_peek(trans, &dir_iter, dir_u, dir,
-			      BTREE_ITER_intent|BTREE_ITER_with_updates);
+	ret = bch2_inode_peek(trans, &dir_iter, dir_u, dir, BTREE_ITER_intent);
 	if (ret)
 		goto err;
 
+	/* Inherit casefold state from parent. */
+	if (S_ISDIR(mode))
+		new_inode->bi_flags |= dir_u->bi_flags & BCH_INODE_casefolded;
+
 	if (!(flags & BCH_CREATE_SNAPSHOT)) {
 		/* Normal create path - allocate a new inode: */
 		bch2_inode_init_late(new_inode, now, uid, gid, mode, rdev, dir_u);
@@ -152,7 +155,6 @@ int bch2_create_trans(struct btree_trans *trans,
 		if (is_subdir_for_nlink(new_inode))
 			dir_u->bi_nlink++;
 		dir_u->bi_mtime = dir_u->bi_ctime = now;
-		dir_u->bi_size += dirent_occupied_size(name);
 
 		ret = bch2_inode_write(trans, &dir_iter, dir_u);
 		if (ret)
@@ -163,7 +165,8 @@ int bch2_create_trans(struct btree_trans *trans,
 					 name,
 					 dir_target,
 					 &dir_offset,
-					 STR_HASH_must_create|BTREE_ITER_with_updates);
+					 &dir_u->bi_size,
+					 STR_HASH_must_create);
 		if (ret)
 			goto err;
 
@@ -221,13 +224,14 @@ int bch2_link_trans(struct btree_trans *trans,
 	}
 
 	dir_u->bi_mtime = dir_u->bi_ctime = now;
-	dir_u->bi_size += dirent_occupied_size(name);
 
 	dir_hash = bch2_hash_info_init(c, dir_u);
 
 	ret = bch2_dirent_create(trans, dir, &dir_hash,
 				 mode_to_type(inode_u->bi_mode),
-				 name, inum.inum, &dir_offset,
+				 name, inum.inum,
+				 &dir_offset,
+				 &dir_u->bi_size,
 				 STR_HASH_must_create);
 	if (ret)
 		goto err;
@@ -266,8 +270,16 @@ int bch2_unlink_trans(struct btree_trans *trans,
 
 	dir_hash = bch2_hash_info_init(c, dir_u);
 
-	ret = bch2_dirent_lookup_trans(trans, &dirent_iter, dir, &dir_hash,
-				       name, &inum, BTREE_ITER_intent);
+	struct bkey_s_c dirent_k =
+		bch2_hash_lookup(trans, &dirent_iter, bch2_dirent_hash_desc,
+				 &dir_hash, dir, name, BTREE_ITER_intent);
+	ret = bkey_err(dirent_k);
+	if (ret)
+		goto err;
+
+	ret = bch2_dirent_read_target(trans, dir, bkey_s_c_to_dirent(dirent_k), &inum);
+	if (ret > 0)
+		ret = -ENOENT;
 	if (ret)
 		goto err;
 
@@ -324,7 +336,7 @@ int bch2_unlink_trans(struct btree_trans *trans,
 
 	dir_u->bi_mtime = dir_u->bi_ctime = inode_u->bi_ctime = now;
 	dir_u->bi_nlink -= is_subdir_for_nlink(inode_u);
-	dir_u->bi_size	-= dirent_occupied_size(name);
+	dir_u->bi_size	-= bkey_bytes(dirent_k.k);
 
 	ret =   bch2_hash_delete_at(trans, bch2_dirent_hash_desc,
 				    &dir_hash, &dirent_iter,
@@ -420,8 +432,8 @@ int bch2_rename_trans(struct btree_trans *trans,
 	}
 
 	ret = bch2_dirent_rename(trans,
-				 src_dir, &src_hash,
-				 dst_dir, &dst_hash,
+				 src_dir, &src_hash, &src_dir_u->bi_size,
+				 dst_dir, &dst_hash, &dst_dir_u->bi_size,
 				 src_name, &src_inum, &src_offset,
 				 dst_name, &dst_inum, &dst_offset,
 				 mode);
@@ -463,14 +475,6 @@ int bch2_rename_trans(struct btree_trans *trans,
 		goto err;
 	}
 
-	if (mode == BCH_RENAME) {
-		src_dir_u->bi_size -= dirent_occupied_size(src_name);
-		dst_dir_u->bi_size += dirent_occupied_size(dst_name);
-	}
-
-	if (mode == BCH_RENAME_OVERWRITE)
-		src_dir_u->bi_size -= dirent_occupied_size(src_name);
-
 	if (src_inode_u->bi_parent_subvol)
 		src_inode_u->bi_parent_subvol = dst_dir.subvol;
 
diff --git a/fs/bcachefs/fsck.c b/fs/bcachefs/fsck.c
index 53a421ff136d..24ad1a42d169 100644
--- a/fs/bcachefs/fsck.c
+++ b/fs/bcachefs/fsck.c
@@ -1132,10 +1132,7 @@ static int check_directory_size(struct btree_trans *trans,
 		if (k.k->type != KEY_TYPE_dirent)
 			continue;
 
-		struct bkey_s_c_dirent dirent = bkey_s_c_to_dirent(k);
-		struct qstr name = bch2_dirent_get_name(dirent);
-
-		new_size += dirent_occupied_size(&name);
+		new_size += bkey_bytes(k.k);
 	}
 	bch2_trans_iter_exit(trans, &iter);
 
-- 
2.45.2