From 741a7bea79eae6361c8d7499f1f6a900b65c120e Mon Sep 17 00:00:00 2001 From: Chao Yu Date: Mon, 6 Jul 2015 20:30:40 +0800 Subject: [PATCH] f2fs: restrict multimedia filename When testing with fs_mark, some blocks were written out as cold data which were mixed with warm data, resulting in splitting more bios. This is because fs_mark will create file with random filename as below: 559551ee~~~~~~~~15Z29OCC05JCKQP60JQ42MKV 559551ee~~~~~~~~NZAZ6X8OA8LHIIP6XD0L58RM 559551ef~~~~~~~~B15YDSWAK789HPSDZKYTW6WM 559551f1~~~~~~~~2DAE5DPS79785BUNTFWBEMP3 559551f1~~~~~~~~1MYDY0BKSQCJPI32Q8C514RM 559551f1~~~~~~~~YQOTMAOMN5CVRFOUNI026MP4 559551f3~~~~~~~~1WF42LPRTQJNPPGR3EINKMPE 559551f3~~~~~~~~8Y2NRK7CEPPAA02LY936PJPG They are regarded as cold file since their filename are ended with multimedia files' extension, but this should be wrong as we only match the extension of filename, not the whole one. In this patch, we try to fix the format of multimedia filename to: "filename + '.' + extension", then we set cold file only its filename matches the format. So after this change, it will reduce the probability we set the wrong cold file, also it helps a little for fs_mark's performance on f2fs. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim --- fs/f2fs/namei.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c index df315dcdd35d..1856d5ecd809 100644 --- a/fs/f2fs/namei.c +++ b/fs/f2fs/namei.c @@ -91,7 +91,14 @@ static int is_multimedia_file(const unsigned char *s, const char *sub) size_t slen = strlen(s); size_t sublen = strlen(sub); - if (sublen > slen) + /* + * filename format of multimedia file should be defined as: + * "filename + '.' + extension". + */ + if (slen < sublen + 2) + return 0; + + if (s[slen - sublen - 1] != '.') return 0; return !strncasecmp(s + slen - sublen, sub, sublen);