Re: [PATCH] fat: eliminate iterations in fat_search_long in case of EOD

From: OGAWA Hirofumi
Date: Sun Jan 20 2013 - 05:58:35 EST


Namjae Jeon <linkinjeon@xxxxxxxxx> writes:

> From: Namjae Jeon <namjae.jeon@xxxxxxxxxxx>
>
> When searching a directory for names, we can stop checking for further
> entries if we detect End of Directory, i.e. if (de->name[0] == 0x00).The
> current code traverses the cluster chain of a directory until a hit is
> found or till the last cluster for that directory, ignoring the EOD mark.
> Fix this.

f_pos still works fine after this change?

> Signed-off-by: Namjae Jeon <namjae.jeon@xxxxxxxxxxx>
> Signed-off-by: Ravishankar N <ravi.n1@xxxxxxxxxxx>
> ---
> fs/fat/dir.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/fs/fat/dir.c b/fs/fat/dir.c
> index 58bf744..cde0e69 100644
> --- a/fs/fat/dir.c
> +++ b/fs/fat/dir.c
> @@ -484,10 +484,10 @@ parse_record:
> nr_slots = 0;
> if (de->name[0] == DELETED_FLAG)
> continue;
> + if (!de->name[0])
> + goto end_of_dir;
> if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME))
> continue;
> - if (de->attr != ATTR_EXT && IS_FREE(de->name))
> - continue;
> if (de->attr == ATTR_EXT) {
> int status = fat_parse_long(inode, &cpos, &bh, &de,
> &unicode, &nr_slots);

--
OGAWA Hirofumi <hirofumi@xxxxxxxxxxxxxxxxxx>
--
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