Re: [PATCH 1/2] f2fs: compress: fix to disallow wildcard extension for hot/cold file

[Jaegeuk Kim]

On 05/18, Chao Yu wrote:
> If all files are hot or cold, hot/cold separation is not needed anymore,
> so let's disallow configure wildcard extension.

We need to be able to set hot/cold on the fly?

> 
> Fixes: 4c8ff7095bef ("f2fs: support data compression")
> Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
> ---
>  fs/f2fs/f2fs.h  |  1 +
>  fs/f2fs/namei.c | 12 ++++++++----
>  fs/f2fs/sysfs.c |  3 +++
>  3 files changed, 12 insertions(+), 4 deletions(-)
> 
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index b753cc88c77e..ecb13c3b458d 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -3322,6 +3322,7 @@ void f2fs_handle_failed_inode(struct inode *inode);
>  /*
>   * namei.c
>   */
> +bool f2fs_is_wildcard_char(const char *ext);
>  int f2fs_update_extension_list(struct f2fs_sb_info *sbi, const char *name,
>  							bool hot, bool set);
>  struct dentry *f2fs_get_parent(struct dentry *child);
> diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
> index a9cd9cf97229..8d78b96a8b3b 100644
> --- a/fs/f2fs/namei.c
> +++ b/fs/f2fs/namei.c
> @@ -153,15 +153,17 @@ static struct inode *f2fs_new_inode(struct inode *dir, umode_t mode)
>  	return ERR_PTR(err);
>  }
>  
> +bool f2fs_is_wildcard_char(const char *ext)
> +{
> +	return *ext == '*' && strlen(ext) == 1;
> +}
> +
>  static inline int is_extension_exist(const unsigned char *s, const char *sub)
>  {
>  	size_t slen = strlen(s);
>  	size_t sublen = strlen(sub);
>  	int i;
>  
> -	if (sublen == 1 && *sub == '*')
> -		return 1;
> -
>  	/*
>  	 * filename format of multimedia file should be defined as:
>  	 * "filename + '.' + extension + (optional: '.' + temp extension)".
> @@ -306,9 +308,11 @@ static void set_compress_inode(struct f2fs_sb_info *sbi, struct inode *inode,
>  	ext = F2FS_OPTION(sbi).extensions;
>  
>  	for (i = 0; i < ext_cnt; i++) {
> +		if (f2fs_is_wildcard_char(ext[i]))
> +			goto set_compress;
>  		if (!is_extension_exist(name, ext[i]))
>  			continue;
> -
> +set_compress:
>  		set_compress_context(inode);
>  		return;
>  	}
> diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
> index dc71bc968c72..ff5acb4de1b6 100644
> --- a/fs/f2fs/sysfs.c
> +++ b/fs/f2fs/sysfs.c
> @@ -343,6 +343,9 @@ static ssize_t __sbi_store(struct f2fs_attr *a,
>  		if (strlen(name) >= F2FS_EXTENSION_LEN)
>  			return -EINVAL;
>  
> +		if (f2fs_is_wildcard_char(name))
> +			return -EINVAL;
> +
>  		down_write(&sbi->sb_lock);
>  
>  		ret = f2fs_update_extension_list(sbi, name, hot, set);
> -- 
> 2.29.2