[CRIU] [PATCH 1/1] simplify the "ignore filesystem-subtype" logic

[Tycho Andersen]

On Fri, Apr 10, 2015 at 06:24:50PM +0200, Oleg Nesterov wrote:
> We can simply overwrite the dot symbol right after the kernel reports
> it to us.

I have no objections, although is it possible that we would ever want
this information? e.g. to pass to a plugin that knows how to unmount a
specific fuse filesystem?

Tycho

> Signed-off-by: Oleg Nesterov <oleg at redhat.com>
> ---
>  mount.c      |   17 +----------------
>  proc_parse.c |   10 +++++++++-
>  2 files changed, 10 insertions(+), 17 deletions(-)
> 
> diff --git a/mount.c b/mount.c
> index b370627..8b57729 100644
> --- a/mount.c
> +++ b/mount.c
> @@ -1344,7 +1344,7 @@ bool add_fsname_auto(const char *names)
>  	return fsauto_names != NULL;
>  }
>  
> -static struct fstype *__find_fstype_by_name(char *_fst, bool force_auto)
> +static struct fstype *__find_fstype_by_name(char *fst, bool force_auto)
>  {
>  	int i;
>  
> @@ -1354,22 +1354,7 @@ static struct fstype *__find_fstype_by_name(char *_fst, bool force_auto)
>  	 * anything is wrong, almost every fs has its own features)
>  	 * 2nd -- save some space in the image (since we scan all
>  	 * names anyway)
> -	 *
> -	 * The kernel reports "subtypes" sometimes and the valid
> -	 * type-vs-subtype delimiter is the dot symbol. We disregard any
> -	 * subtypes for the purpose of finding the fstype.
>  	 */
> -	char fst[1024];
> -
> -	for (i = 0; _fst[i] && i < sizeof(fst) - 1; i++) {
> -		if (_fst[i] == '.')
> -			break;
> -
> -		fst[i] = _fst[i];
> -	}
> -
> -	fst[i] = 0;
> -
>  	for (i = 1; i < ARRAY_SIZE(fstypes); i++) {
>  		struct fstype *fstype = fstypes + i;
>  
> diff --git a/proc_parse.c b/proc_parse.c
> index 2f05699..5d50979 100644
> --- a/proc_parse.c
> +++ b/proc_parse.c
> @@ -947,7 +947,7 @@ static int parse_mountinfo_ent(char *str, struct mount_info *new, char **fsname)
>  {
>  	unsigned int kmaj, kmin;
>  	int ret, n;
> -	char *opt = NULL;
> +	char *sub, *opt = NULL;
>  
>  	new->mountpoint = xmalloc(PATH_MAX);
>  	if (new->mountpoint == NULL)
> @@ -981,6 +981,14 @@ static int parse_mountinfo_ent(char *str, struct mount_info *new, char **fsname)
>  	ret = sscanf(str, "%ms %ms %ms", fsname, &new->source, &opt);
>  	if (ret != 3)
>  		goto err;
> +	/*
> +	 * The kernel reports "subtypes" sometimes and the valid
> +	 * type-vs-subtype delimiter is the dot symbol. We disregard
> +	 * any subtypes for the purpose of finding the fstype.
> +	 */
> +	sub = strchr(*fsname, '.');
> +	if (sub)
> +		*sub = 0;
>  
>  	new->fstype = find_fstype_by_name(*fsname);
>  
> -- 
> 1.5.5.1
> 
>