> This helper is used to lookup empty dentry set. If there are no enough
> empty dentries at the input location, this helper will return the number
> of dentries that need to be skipped for the next lookup.
>
> Signed-off-by: Yuezhang Mo <Yuezhang.Mo@xxxxxxxx>
> Reviewed-by: Andy Wu <Andy.Wu@xxxxxxxx>
> Reviewed-by: Aoyama Wataru <wataru.aoyama@xxxxxxxx>
> ---
> fs/exfat/dir.c | 77 +++++++++++++++++++++++++++++++++++++++++++++
> fs/exfat/exfat_fs.h | 3 ++
> 2 files changed, 80 insertions(+)
>
> diff --git a/fs/exfat/dir.c b/fs/exfat/dir.c index
> cea9231d2fda..a5c8cd19aca6 100644
> --- a/fs/exfat/dir.c
> +++ b/fs/exfat/dir.c
> @@ -950,6 +950,83 @@ int exfat_get_dentry_set(struct exfat_entry_set_cache
> *es,
> return -EIO;
> }
>
> +static int exfat_validate_empty_dentry_set(struct exfat_entry_set_cache
> +*es) {
> + struct exfat_dentry *ep;
> + struct buffer_head *bh;
> + int i, off;
> + bool unused_hit = false;
> +
> + for (i = 0; i < es->num_entries; i++) {
> + ep = exfat_get_dentry_cached(es, i);
> + if (ep->type == EXFAT_UNUSED)
> + unused_hit = true;
> + else if (IS_EXFAT_DELETED(ep->type)) {
Although it violates the specification for a deleted entry to follow an unused
entry, some exFAT implementations could work like this.
Therefore, to improve compatibility, why don't we allow this?
I believe there will be no functional problem even if this is allowed.
> + if (unused_hit)
> + goto out;
> + } else {
> + if (unused_hit)
> + goto out;
Label "out" does not look like an error situation.
Let's use "out_err" instead of "out".
> +
> + i++;
> + goto count_skip_entries;
> + }
> + }
> +
> + return 0;
