From 756daf263ea53a8bfc89db26cb92e963953253a1 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Mon, 23 Mar 2015 13:37:38 +1100 Subject: VFS: replace {, total_}link_count in task_struct with pointer to nameidata task_struct currently contains two ad-hoc members for use by the VFS: link_count and total_link_count. These are only interesting to fs/namei.c, so exposing them explicitly is poor layering. Incidentally, link_count isn't used anymore, so it can just die. This patches replaces those with a single pointer to 'struct nameidata'. This structure represents the current filename lookup of which there can only be one per process, and is a natural place to store total_link_count. This will allow the current "nameidata" argument to all follow_link operations to be removed as current->nameidata can be used instead in the _very_ few instances that care about it at all. As there are occasional circumstances where pathname lookup can recurse, such as through kern_path_locked, we always save and old current->nameidata (if there is one) when setting a new value, and make sure any active link_counts are preserved. follow_mount and follow_automount now get a 'struct nameidata *' rather than 'int flags' so that they can directly access total_link_count, rather than going through 'current'. Suggested-by: Al Viro Signed-off-by: NeilBrown Signed-off-by: Al Viro --- include/linux/sched.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/sched.h') diff --git a/include/linux/sched.h b/include/linux/sched.h index 26a2e6122734..f6c9b69d66f2 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1461,7 +1461,7 @@ struct task_struct { it with task_lock()) - initialized normally by setup_new_exec */ /* file system info */ - int link_count, total_link_count; + struct nameidata *nameidata; #ifdef CONFIG_SYSVIPC /* ipc stuff */ struct sysv_sem sysvsem; -- cgit v1.2.3