hfsplus: extract hidden directory search into a helper function

In hfsplus_fill_super(), the process of looking up the hidden directory
involves initializing a catalog search, building a search key, reading
the b-tree record, and releasing the search data.

Currently, this logic is open-coded directly within the main superblock
initialization routine. This makes hfsplus_fill_super() quite lengthy
and its error handling paths less straightforward.

Extract the hidden directory search sequence into a new helper function,
hfsplus_get_hidden_dir_entry(). This improves overall code readability,
cleanly encapsulates the hfs_find_data lifecycle, and simplifies the
error exits in hfsplus_fill_super().

Signed-off-by: Zilin Guan <zilin@seu.edu.cn>
Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com>
Tested-by: Viacheslav Dubeyko <slava@dubeyko.com>
Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com>

diff --git a/fs/hfsplus/super.c b/fs/hfsplus/super.c
index a36243b08c7cf43efbc863e05dc89a8a7613cfa5..8bd1627ffc9c8206d5e29119318bb45027f36ac8 100644 (file)
--- a/fs/hfsplus/super.c
+++ b/fs/hfsplus/super.c
@@ -424,12 +424,35 @@ void hfsplus_prepare_volume_header_for_commit(struct hfsplus_vh *vhdr)
        vhdr->attributes |= cpu_to_be32(HFSPLUS_VOL_INCNSTNT);
 }
 
+static inline int hfsplus_get_hidden_dir_entry(struct super_block *sb,
+                                              const struct qstr *str,
+                                              hfsplus_cat_entry *entry)
+{
+       struct hfs_find_data fd;
+       int err;
+
+       err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
+       if (unlikely(err))
+               return err;
+
+       err = hfsplus_cat_build_key(sb, fd.search_key, HFSPLUS_ROOT_CNID, str);
+       if (unlikely(err))
+               goto free_fd;
+
+       err = hfsplus_brec_read_cat(&fd, entry);
+       if (err)
+               err = -ENOENT;
+
+free_fd:
+       hfs_find_exit(&fd);
+       return err;
+}
+
 static int hfsplus_fill_super(struct super_block *sb, struct fs_context *fc)
 {
        struct hfsplus_vh *vhdr;
        struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
        hfsplus_cat_entry entry;
-       struct hfs_find_data fd;
        struct inode *root, *inode;
        struct qstr str;
        struct nls_table *nls;
@@ -565,16 +588,14 @@ static int hfsplus_fill_super(struct super_block *sb, struct fs_context *fc)
 
        str.len = sizeof(HFSP_HIDDENDIR_NAME) - 1;
        str.name = HFSP_HIDDENDIR_NAME;
-       err = hfs_find_init(sbi->cat_tree, &fd);
-       if (err)
-               goto out_put_root;
-       err = hfsplus_cat_build_key(sb, fd.search_key, HFSPLUS_ROOT_CNID, &str);
-       if (unlikely(err < 0)) {
-               hfs_find_exit(&fd);
+       err = hfsplus_get_hidden_dir_entry(sb, &str, &entry);
+       if (err == -ENOENT) {
+               /*
+                * Hidden directory is absent or it cannot be read.
+                */
+       } else if (unlikely(err)) {
                goto out_put_root;
-       }
-       if (!hfsplus_brec_read_cat(&fd, &entry)) {
-               hfs_find_exit(&fd);
+       } else {
                if (entry.type != cpu_to_be16(HFSPLUS_FOLDER)) {
                        err = -EIO;
                        goto out_put_root;
@@ -585,8 +606,7 @@ static int hfsplus_fill_super(struct super_block *sb, struct fs_context *fc)
                        goto out_put_root;
                }
                sbi->hidden_dir = inode;
-       } else
-               hfs_find_exit(&fd);
+       }
 
        if (!sb_rdonly(sb)) {
                /*