From: Eric W. Biederman <ebiederm@xmission.com>
Date: Thu, 13 Feb 2014 18:24:23 +0000 (-0800)
Subject: proc: Update proc_flush_task_mnt to use d_invalidate
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=bbd5192412fdedbae00888316bfe350bf89d0458;p=linux-beck.git

proc: Update proc_flush_task_mnt to use d_invalidate

Now that d_invalidate always succeeds and flushes mount points use
it in stead of a combination of shrink_dcache_parent and d_drop
in proc_flush_task_mnt.  This removes the danger of a mount point
under /proc/<pid>/... becoming unreachable after the d_drop.

Reviewed-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---

diff --git a/fs/proc/base.c b/fs/proc/base.c
index b4fe0ee08942..00cd85f18bcc 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -2639,8 +2639,7 @@ static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
 	/* no ->d_hash() rejects on procfs */
 	dentry = d_hash_and_lookup(mnt->mnt_root, &name);
 	if (dentry) {
-		shrink_dcache_parent(dentry);
-		d_drop(dentry);
+		d_invalidate(dentry);
 		dput(dentry);
 	}
 
@@ -2660,8 +2659,7 @@ static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
 	name.len = snprintf(buf, sizeof(buf), "%d", pid);
 	dentry = d_hash_and_lookup(dir, &name);
 	if (dentry) {
-		shrink_dcache_parent(dentry);
-		d_drop(dentry);
+		d_invalidate(dentry);
 		dput(dentry);
 	}