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* [PATCH] fat: eliminate iterations in fat_search_long in case of EOD
@ 2013-01-19  2:19 Namjae Jeon
  2013-01-20 10:58 ` OGAWA Hirofumi
  0 siblings, 1 reply; 5+ messages in thread
From: Namjae Jeon @ 2013-01-19  2:19 UTC (permalink / raw)
  To: hirofumi, akpm
  Cc: linux-fsdevel, linux-kernel, Namjae Jeon, Namjae Jeon,
	Ravishankar N

From: Namjae Jeon <namjae.jeon@samsung.com>

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.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Ravishankar N <ravi.n1@samsung.com>
---
 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);
-- 
1.7.9.5

^ permalink raw reply related	[flat|nested] 5+ messages in thread

* Re: [PATCH] fat: eliminate iterations in fat_search_long in case of EOD
  2013-01-19  2:19 [PATCH] fat: eliminate iterations in fat_search_long in case of EOD Namjae Jeon
@ 2013-01-20 10:58 ` OGAWA Hirofumi
  2013-01-21  4:15   ` Namjae Jeon
  0 siblings, 1 reply; 5+ messages in thread
From: OGAWA Hirofumi @ 2013-01-20 10:58 UTC (permalink / raw)
  To: Namjae Jeon; +Cc: akpm, linux-fsdevel, linux-kernel, Namjae Jeon, Ravishankar N

Namjae Jeon <linkinjeon@gmail.com> writes:

> From: Namjae Jeon <namjae.jeon@samsung.com>
>
> 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@samsung.com>
> Signed-off-by: Ravishankar N <ravi.n1@samsung.com>
> ---
>  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@mail.parknet.co.jp>

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH] fat: eliminate iterations in fat_search_long in case of EOD
  2013-01-20 10:58 ` OGAWA Hirofumi
@ 2013-01-21  4:15   ` Namjae Jeon
  2013-01-21  5:41     ` OGAWA Hirofumi
  0 siblings, 1 reply; 5+ messages in thread
From: Namjae Jeon @ 2013-01-21  4:15 UTC (permalink / raw)
  To: OGAWA Hirofumi
  Cc: akpm, linux-fsdevel, linux-kernel, Namjae Jeon, Ravishankar N

2013/1/20, OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>:
> Namjae Jeon <linkinjeon@gmail.com> writes:
>
>> From: Namjae Jeon <namjae.jeon@samsung.com>
>>
>> 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?
Hi OGAWA.
I can not find f_pos usage in fat_search_long function.
Maybe, Have you seen other function such as __fat_readdir ?
Let me know your opinion.

Thanks.
>
>> Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
>> Signed-off-by: Ravishankar N <ravi.n1@samsung.com>
>> ---
>>  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@mail.parknet.co.jp>
>

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH] fat: eliminate iterations in fat_search_long in case of EOD
  2013-01-21  4:15   ` Namjae Jeon
@ 2013-01-21  5:41     ` OGAWA Hirofumi
  2013-01-21  6:40       ` Namjae Jeon
  0 siblings, 1 reply; 5+ messages in thread
From: OGAWA Hirofumi @ 2013-01-21  5:41 UTC (permalink / raw)
  To: Namjae Jeon; +Cc: akpm, linux-fsdevel, linux-kernel, Namjae Jeon, Ravishankar N

Namjae Jeon <linkinjeon@gmail.com> writes:

> 2013/1/20, OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>:
>> Namjae Jeon <linkinjeon@gmail.com> writes:
>>
>>> From: Namjae Jeon <namjae.jeon@samsung.com>
>>>
>>> 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?
> Hi OGAWA.
> I can not find f_pos usage in fat_search_long function.
> Maybe, Have you seen other function such as __fat_readdir ?
> Let me know your opinion.

Ah, I see. Only ->lookup. So, this makes behavior more strange.
I.e. readdir() returns beyond 0, but lookup() can't find it?

Thanks.
-- 
OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH] fat: eliminate iterations in fat_search_long in case of EOD
  2013-01-21  5:41     ` OGAWA Hirofumi
@ 2013-01-21  6:40       ` Namjae Jeon
  0 siblings, 0 replies; 5+ messages in thread
From: Namjae Jeon @ 2013-01-21  6:40 UTC (permalink / raw)
  To: OGAWA Hirofumi
  Cc: akpm, linux-fsdevel, linux-kernel, Namjae Jeon, Ravishankar N

2013/1/21, OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>:
> Namjae Jeon <linkinjeon@gmail.com> writes:
>
>> 2013/1/20, OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>:
>>> Namjae Jeon <linkinjeon@gmail.com> writes:
>>>
>>>> From: Namjae Jeon <namjae.jeon@samsung.com>
>>>>
>>>> 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?
>> Hi OGAWA.
>> I can not find f_pos usage in fat_search_long function.
>> Maybe, Have you seen other function such as __fat_readdir ?
>> Let me know your opinion.
>
> Ah, I see. Only ->lookup. So, this makes behavior more strange.
> I.e. readdir() returns beyond 0, but lookup() can't find it?
Yes, Good point. I will check other places included readdir.
Thanks for review!
>
> Thanks.
> --
> OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
>

^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2013-01-21  6:40 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-01-19  2:19 [PATCH] fat: eliminate iterations in fat_search_long in case of EOD Namjae Jeon
2013-01-20 10:58 ` OGAWA Hirofumi
2013-01-21  4:15   ` Namjae Jeon
2013-01-21  5:41     ` OGAWA Hirofumi
2013-01-21  6:40       ` Namjae Jeon

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