[PATCH v3 11/11] NFSv4: Don't request cache consistency attributes on some writes and commits

[Trond Myklebust <Trond.Myklebust@xxxxxxxxxx>]

We don't need cache consistency information when we're doing O_DIRECT
writes or commits. Ditto for the case of delegated writes and commits.

Signed-off-by: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx>
---
 fs/nfs/nfs4proc.c |   30 ++++++++++++++++++++++++++++--
 1 files changed, 28 insertions(+), 2 deletions(-)

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index c746b0c..eb6a85a 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -3401,11 +3401,25 @@ void nfs4_reset_write(struct rpc_task *task, struct nfs_write_data *data)
 }
 EXPORT_SYMBOL_GPL(nfs4_reset_write);
 
+static
+bool nfs4_write_need_cache_consistency_data(const struct nfs_write_data *data)
+{
+	const struct nfs_pgio_header *hdr = data->header;
+
+	/* Don't request attributes for pNFS or O_DIRECT writes */
+	if (data->ds_clp != NULL || hdr->dreq != NULL)
+		return false;
+	/* Otherwise, request attributes if and only if we don't hold
+	 * a delegation
+	 */
+	return nfs_have_delegation(hdr->inode, FMODE_READ) == 0;
+}
+
 static void nfs4_proc_write_setup(struct nfs_write_data *data, struct rpc_message *msg)
 {
 	struct nfs_server *server = NFS_SERVER(data->header->inode);
 
-	if (data->ds_clp) {
+	if (!nfs4_write_need_cache_consistency_data(data)) {
 		data->args.bitmask = NULL;
 		data->res.fattr = NULL;
 	} else
@@ -3458,11 +3472,23 @@ static int nfs4_commit_done(struct rpc_task *task, struct nfs_commit_data *data)
 	return data->commit_done_cb(task, data);
 }
 
+static
+bool nfs4_commit_need_cache_consistency_data(const struct nfs_commit_data *data)
+{
+	/* Don't request attributes for pNFS or O_DIRECT writes */
+	if (data->ds_clp != NULL || data->dreq != NULL)
+		return false;
+	/* Otherwise, request attributes if and only if we don't hold
+	 * a delegation
+	 */
+	return nfs_have_delegation(data->inode, FMODE_READ) == 0;
+}
+
 static void nfs4_proc_commit_setup(struct nfs_commit_data *data, struct rpc_message *msg)
 {
 	struct nfs_server *server = NFS_SERVER(data->inode);
 
-	if (data->lseg) {
+	if (!nfs4_commit_need_cache_consistency_data(data)) {
 		data->args.bitmask = NULL;
 		data->res.fattr = NULL;
 	} else
-- 
1.7.7.6

--
To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html