[CRIU] [PATCH] cr-dump: call stat for /proc/pid/fd/X directly

[Pavel Emelyanov]

Applied, but one comment inline

On 01/19/2013 06:55 PM, Andrey Vagin wrote:
> This patch can be committed instead of:
> [PATCH 1/6] cr-dump: move parasite_drain_fds_seized out of dump_task_files
> [PATCH 2/6] cr-dump: fix dumping file locks in a mount namespace
> 
> readlink is not required here and a file can be unavailable,
> if a process is in another mnt namespace
> 
> Signed-off-by: Andrey Vagin <avagin at openvz.org>
> ---
>  cr-dump.c | 23 +++++------------------
>  1 file changed, 5 insertions(+), 18 deletions(-)
> 
> diff --git a/cr-dump.c b/cr-dump.c
> index e94aa51..6a274f3 100644
> --- a/cr-dump.c
> +++ b/cr-dump.c
> @@ -694,36 +694,23 @@ err:
>  static int get_fd_by_ino(unsigned long i_no, struct parasite_drain_fd *dfds,
>  			pid_t pid)
>  {
> -	int  i, ret = -1;
> -	char path[PATH_MAX];
> -	char buf[40];
> +	int  i;
> +	char buf[PATH_MAX];
>  	struct stat fd_stat;
>  
> -	i = 0;
> -	while (i < dfds->nr_fds) {
> +	for (i = 0; i < dfds->nr_fds; i++) {
>  		snprintf(buf, sizeof(buf), "/proc/%d/fd/%d", pid,
>  			dfds->fds[i]);
> -		buf[39] = '\0';
> -
> -		memset(path, 0, sizeof(path));
> -		ret = readlink(buf, path, sizeof(path));
> -		if (ret < 0) {
> -			pr_err("Read link %s failed!\n", buf);
> -			goto err;
> -		}
>  
> -		if (stat(path, &fd_stat) == -1) {
> -			i++;
> -			pr_msg("Could not get %s stat!\n", path);
> +		if (stat(buf, &fd_stat) == -1) {
> +			pr_msg("Could not get %s stat!\n", buf);
>  			continue;
>  		}
>  
>  		if (fd_stat.st_ino == i_no)

Is it correct to check inode only? Files from different disks
may have equal inodes.

>  			return dfds->fds[i];
> -		i++;
>  	}
>  
> -err:
>  	return -1;
>  }
>  
>