Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Thu, 22 Jun 2023 00:10:57 -0700
From:   Jaegeuk Kim <jaegeuk@kernel.org>
To:     Chao Yu <chao@kernel.org>
Cc:     linux-kernel@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net
Subject: Re: [f2fs-dev] [PATCH v2] f2fs: compress tmp files given extension
Message-ID: <ZJP0AaU/0ixqWPvv@google.com>
References: <20230606203645.3926651-1-jaegeuk@kernel.org>
 <ZIjqKHDUmN6u9pXa@google.com>
 <a1a84df4-aa7a-d684-8694-fa8489baa9c2@kernel.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <a1a84df4-aa7a-d684-8694-fa8489baa9c2@kernel.org>
Precedence: bulk

On 06/20, Chao Yu wrote:
> On 2023/6/14 6:14, Jaegeuk Kim wrote:
> > Let's compress tmp files for the given extension list.
> > 
> > This patch does not change the previous behavior, but allow the cases as below.
> > 
> > Extention example: "ext"
> > 
> > - abc.ext : allow
> > - abc.ext.abc : allow
> > - abc.extm : not allow
> > 
> > Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
> > ---
> > 
> >   Change log from v1:
> >    - refactor to allow abc.ext.dontcare only
> > 
> >   fs/f2fs/namei.c | 18 +++++++++++-------
> >   1 file changed, 11 insertions(+), 7 deletions(-)
> > 
> > diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
> > index 3e35eb7dbb8f..49573ef4115d 100644
> > --- a/fs/f2fs/namei.c
> > +++ b/fs/f2fs/namei.c
> > @@ -23,7 +23,7 @@
> >   #include <trace/events/f2fs.h>
> >   static inline bool is_extension_exist(const unsigned char *s, const char *sub,
> > -						bool tmp_ext)
> > +						bool tmp_ext, bool tmp_dot)
> >   {
> >   	size_t slen = strlen(s);
> >   	size_t sublen = strlen(sub);
> > @@ -49,8 +49,12 @@ static inline bool is_extension_exist(const unsigned char *s, const char *sub,
> >   	for (i = 1; i < slen - sublen; i++) {
> >   		if (s[i] != '.')
> >   			continue;
> > -		if (!strncasecmp(s + i + 1, sub, sublen))
> > -			return true;
> > +		if (!strncasecmp(s + i + 1, sub, sublen)) {
> > +			if (!tmp_dot)
> > +				return true;
> > +			if (i == slen - sublen - 1 || s[i + 1 + sublen] == '.')
> 
> Do you mean?
> 
> if (i == slen - sublen - 1 && s[i + 1 + sublen] == '.')

I don't think so.

> 
> > +				return true;
> > +		}
> >   	}
> >   	return false;
> > @@ -148,7 +152,7 @@ static void set_compress_new_inode(struct f2fs_sb_info *sbi, struct inode *dir,
> >   	cold_count = le32_to_cpu(sbi->raw_super->extension_count);
> >   	hot_count = sbi->raw_super->hot_ext_count;
> >   	for (i = cold_count; i < cold_count + hot_count; i++)
> > -		if (is_extension_exist(name, extlist[i], false))
> > +		if (is_extension_exist(name, extlist[i], false, false))
> 
> Parameters should be consistent w/ the one in set_file_temperature()?
> 
> if (is_extension_exist(name, extlist[i], true, false))
> 
> >   			break;
> >   	f2fs_up_read(&sbi->sb_lock);
> >   	if (i < (cold_count + hot_count))
> > @@ -156,12 +160,12 @@ static void set_compress_new_inode(struct f2fs_sb_info *sbi, struct inode *dir,
> >   	/* Don't compress unallowed extension. */
> >   	for (i = 0; i < noext_cnt; i++)
> > -		if (is_extension_exist(name, noext[i], false))
> > +		if (is_extension_exist(name, noext[i], false, false))
> 
> is_extension_exist(name, noext[i], true, true) ?
> 
> Thanks,
> 
> >   			return;
> >   	/* Compress wanting extension. */
> >   	for (i = 0; i < ext_cnt; i++) {
> > -		if (is_extension_exist(name, ext[i], false)) {
> > +		if (is_extension_exist(name, ext[i], true, true)) {
> >   			set_compress_context(inode);
> >   			return;
> >   		}
> > @@ -189,7 +193,7 @@ static void set_file_temperature(struct f2fs_sb_info *sbi, struct inode *inode,
> >   	cold_count = le32_to_cpu(sbi->raw_super->extension_count);
> >   	hot_count = sbi->raw_super->hot_ext_count;
> >   	for (i = 0; i < cold_count + hot_count; i++)
> > -		if (is_extension_exist(name, extlist[i], true))
> > +		if (is_extension_exist(name, extlist[i], true, false))
> >   			break;
> >   	f2fs_up_read(&sbi->sb_lock);