teach nfs_get_link() to work in RCU mode
based upon the corresponding patch from Neil's March patchset,
again with kmap-related horrors removed.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index ae9aa0b..aa828e8 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -1087,6 +1087,27 @@
|| NFS_STALE(inode);
}
+int nfs_revalidate_mapping_rcu(struct inode *inode)
+{
+ struct nfs_inode *nfsi = NFS_I(inode);
+ unsigned long *bitlock = &nfsi->flags;
+ int ret = 0;
+
+ if (IS_SWAPFILE(inode))
+ goto out;
+ if (nfs_mapping_need_revalidate_inode(inode)) {
+ ret = -ECHILD;
+ goto out;
+ }
+ spin_lock(&inode->i_lock);
+ if (test_bit(NFS_INO_INVALIDATING, bitlock) ||
+ (nfsi->cache_validity & NFS_INO_INVALID_DATA))
+ ret = -ECHILD;
+ spin_unlock(&inode->i_lock);
+out:
+ return ret;
+}
+
/**
* __nfs_revalidate_mapping - Revalidate the pagecache
* @inode - pointer to host inode