NFSv4: Allow attribute caching with 'noac' mounts if client holds a delegation

If the server has given us a delegation on a file, we _know_ that we can
cache the attribute information even when the user has specified 'noac'.

Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

2 files changed, 18 insertions, 9 deletions

diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index 8d965bddb87e..cac96bcc91e4 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -161,14 +161,17 @@ static int nfs_revalidate_file_size(struct inode *inode, struct file *filp)
         struct nfs_server *server = NFS_SERVER(inode);
         struct nfs_inode *nfsi = NFS_I(inode);
 
-        if (server->flags & NFS_MOUNT_NOAC)
-                goto force_reval;
+        if (nfs_have_delegated_attributes(inode))
+                goto out_noreval;
+
         if (filp->f_flags & O_DIRECT)
                 goto force_reval;
-        if (nfsi->npages != 0)
-                return 0;
-        if (!(nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE) && !nfs_attribute_timeout(inode))
-                return 0;
+        if (nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE)
+                goto force_reval;
+        if (nfs_attribute_timeout(inode))
+                goto force_reval;
+out_noreval:
+        return 0;
 force_reval:
         return __nfs_revalidate_inode(server, inode);
 }
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 2fe6657a5048..099b3518feea 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -742,9 +742,14 @@ int nfs_attribute_timeout(struct inode *inode)
 {
         struct nfs_inode *nfsi = NFS_I(inode);
 
+        return !time_in_range_open(jiffies, nfsi->read_cache_jiffies, nfsi->read_cache_jiffies + nfsi->attrtimeo);
+}
+
+static int nfs_attribute_cache_expired(struct inode *inode)
+{
         if (nfs_have_delegated_attributes(inode))
                 return 0;
-        return !time_in_range_open(jiffies, nfsi->read_cache_jiffies, nfsi->read_cache_jiffies + nfsi->attrtimeo);
+        return nfs_attribute_timeout(inode);
 }
 
 /**
@@ -757,7 +762,7 @@ int nfs_attribute_timeout(struct inode *inode)
 int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
 {
         if (!(NFS_I(inode)->cache_validity & NFS_INO_INVALID_ATTR)
-                        && !nfs_attribute_timeout(inode))
+                        && !nfs_attribute_cache_expired(inode))
                 return NFS_STALE(inode) ? -ESTALE : 0;
         return __nfs_revalidate_inode(server, inode);
 }
@@ -794,7 +799,8 @@ int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping)
         int ret = 0;
 
         if ((nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE)
-                        || nfs_attribute_timeout(inode) || NFS_STALE(inode)) {
+                        || nfs_attribute_cache_expired(inode)
+                        || NFS_STALE(inode)) {
                 ret = __nfs_revalidate_inode(NFS_SERVER(inode), inode);
                 if (ret < 0)
                         goto out;