From: Marc Dionne <marc.c.dionne@gmail.com>
Date: Tue, 25 Jan 2011 23:18:56 +0000 (-0500)
Subject: linux: 2.6.38: Make d_revalidate RCU-walk aware
X-Git-Tag: upstream/1.6.0.pre2^2~33
X-Git-Url: https://git.michaelhowe.org/gitweb/?a=commitdiff_plain;h=f709e62625758e6c65f752b7d29c2ce1123ee9d4;p=packages%2Fo%2Fopenafs.git

linux: 2.6.38: Make d_revalidate RCU-walk aware

Signal to the vfs that we don't support path RCU walk in
d_revalidate.  It will call back in non-RCU mode.

(cherry picked from commit 52556d50298e4a636f07e9a3cf0b6557c882c82d)
Reviewed-on: http://gerrit.openafs.org/3759
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementia.org>

Change-Id: I44d8577feba382a193d1f1735a05db74c3151df0
Reviewed-on: http://gerrit.openafs.org/3870
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementia.org>
---

diff --git a/src/afs/LINUX/osi_vnodeops.c b/src/afs/LINUX/osi_vnodeops.c
index 02aadd48f..f74b1bb7a 100644
--- a/src/afs/LINUX/osi_vnodeops.c
+++ b/src/afs/LINUX/osi_vnodeops.c
@@ -823,7 +823,13 @@ afs_linux_dentry_revalidate(struct dentry *dp, int flags)
     int valid;
     struct afs_fakestat_state fakestate;
 
+#ifdef LOOKUP_RCU
+    /* We don't support RCU path walking */
+    if (nd->flags & LOOKUP_RCU)
+       return -ECHILD;
+#endif
     AFS_GLOCK();
+
     afs_InitFakeStat(&fakestate);
 
     if (dp->d_inode) {