[PATCH] exfat: fix erroneous discard when clear cluster bit

[PATCH] exfat: fix erroneous discard when clear cluster bit

[Hyeongseok Kim]

If mounted with discard option, exFAT issues discard command when clear
cluster bit to remove file. But the input parameter of cluster-to-sector
calculation is abnormally adds reserved cluster size which is 2, leading
to discard unrelated sectors included in target+2 cluster.

Fixes: 1e49a94cf707 ("exfat: add bitmap operations")
Signed-off-by: Hyeongseok Kim <hyeongseok@gmail.com>
---
 fs/exfat/balloc.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/fs/exfat/balloc.c b/fs/exfat/balloc.c
index 761c79c3a4ba..41a1dfd9d98a 100644
--- a/fs/exfat/balloc.c
+++ b/fs/exfat/balloc.c
@@ -186,8 +186,7 @@ void exfat_clear_bitmap(struct inode *inode, unsigned int clu, bool sync)
 		int ret_discard;
 
 		ret_discard = sb_issue_discard(sb,
-			exfat_cluster_to_sector(sbi, clu +
-						EXFAT_RESERVED_CLUSTERS),
+			exfat_cluster_to_sector(sbi, clu),
 			(1 << sbi->sect_per_clus_bits), GFP_NOFS, 0);
 
 		if (ret_discard == -EOPNOTSUPP) {
-- 
2.27.0.83.g0313f36

RE: [PATCH] exfat: fix erroneous discard when clear cluster bit

[Sungjong Seo]

> Subject: [PATCH] exfat: fix erroneous discard when clear cluster bit
> 
> If mounted with discard option, exFAT issues discard command when clear
> cluster bit to remove file. But the input parameter of cluster-to-sector
> calculation is abnormally adds reserved cluster size which is 2, leading
> to discard unrelated sectors included in target+2 cluster.
> 
> Fixes: 1e49a94cf707 ("exfat: add bitmap operations")
> Signed-off-by: Hyeongseok Kim <hyeongseok@gmail.com>
> ---
>  fs/exfat/balloc.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)

Looks good.

Acked-by: Sungjong Seo <sj1557.seo@samsung.com>

Thanks for your work!
Could you remove the wrong comments above set/clear/find bitmap functions
together?

Re: [PATCH] exfat: fix erroneous discard when clear cluster bit

[Hyeongseok Kim]

On 3/2/21 11:41 AM, Sungjong Seo wrote:
>> Subject: [PATCH] exfat: fix erroneous discard when clear cluster bit
>>
>> If mounted with discard option, exFAT issues discard command when clear
>> cluster bit to remove file. But the input parameter of cluster-to-sector
>> calculation is abnormally adds reserved cluster size which is 2, leading
>> to discard unrelated sectors included in target+2 cluster.
>>
>> Fixes: 1e49a94cf707 ("exfat: add bitmap operations")
>> Signed-off-by: Hyeongseok Kim <hyeongseok@gmail.com>
>> ---
>>   fs/exfat/balloc.c | 3 +--
>>   1 file changed, 1 insertion(+), 2 deletions(-)
> Looks good.
>
> Acked-by: Sungjong Seo <sj1557.seo@samsung.com>
>
> Thanks for your work!
> Could you remove the wrong comments above set/clear/find bitmap functions
> together?
>
Done, in V2.
Thanks for the review.