diff options
authorEric W. Biederman <ebiederm@xmission.com>2007-12-10 15:49:36 -0800
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-12-10 19:43:55 -0800
commit3790ee4bd86396558eedd86faac1052cb782e4e1 (patch)
parentd84248bf46582a406116c55b94405c05193773b1 (diff)
proc: remove/Fix proc generic d_revalidate
Ultimately to implement /proc perfectly we need an implementation of d_revalidate because files and directories can be removed behind the back of the VFS, and d_revalidate is the only way we can let the VFS know that this has happened. Unfortunately the linux VFS can not cope with anything in the path to a mount point going away. So a proper d_revalidate method that calls d_drop also needs to call have_submounts which is moderately expensive, so you really don't want a d_revalidate method that unconditionally calls it, but instead only calls it when the backing object has really gone away. proc generic entries only disappear on module_unload (when not counting the fledgling network namespace) so it is quite rare that we actually encounter that case and has not actually caused us real world trouble yet. So until we get a proper test for keeping dentries in the dcache fix the current d_revalidate method by completely removing it. This returns us to the current status quo. So with CONFIG_NETNS=n things should look as they have always looked. For CONFIG_NETNS=y things work most of the time but there are a few rare corner cases that don't behave properly. As the network namespace is barely present in 2.6.24 this should not be a problem. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Pavel Emelyanov <xemul@openvz.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: "Denis V. Lunev" <den@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 files changed, 0 insertions, 7 deletions
diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index 8d49838e555..6a2fe5187b6 100644
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -374,16 +374,9 @@ static int proc_delete_dentry(struct dentry * dentry)
return 1;
-static int proc_revalidate_dentry(struct dentry *dentry, struct nameidata *nd)
- d_drop(dentry);
- return 0;
static struct dentry_operations proc_dentry_operations =
.d_delete = proc_delete_dentry,
- .d_revalidate = proc_revalidate_dentry,