[V9fs-developer,4/7,net/9p] Add gup/zero_copy support to VirtIO transport layer.

Commit Message

Aneesh Kumar K.V Feb. 8, 2011, 6:26 p.m. UTC

None

Patch

diff --git a/net/9p/client.c b/net/9p/client.c
index a05673b..7d027e6 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -93,7 +93,10 @@  static int get_protocol_version(const substring_t *name)
 }
 
 static struct p9_req_t *
-p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...);
+do_p9_client_rpc(struct p9_client *c, int8_t type, int zc, const char *fmt, ...);
+
+#define p9_client_rpc(client, type, fmt...) do_p9_client_rpc(client, type, 0, ##fmt)
+#define p9_client_zcrpc(client, type, fmt..) do_p9_client_rpc(client, type, 1, ##fmt)
 
 /**
  * parse_options - parse mount options into client structure
@@ -583,7 +586,14 @@  p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
 		goto reterr;
 	p9pdu_finalize(req->tc);
 
-	err = c->trans_mod->request(c, req);
+	if (zc) {
+		err = c->trans_mode->zc_request(c, req);
+		if (err == EAGAIN) {
+			err = c->trans_mode->request(c, req);
+		}
+
+	} else
+		err = c->trans_mod->request(c, req);
 	if (err < 0) {
 		if (err != -ERESTARTSYS)
 			c->status = Disconnected;
@@ -1348,7 +1358,8 @@  p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
 		req = p9_client_rpc(clnt, P9_TWRITE, "dqD", fid->fid, offset,
 								rsize, data);
 	else
-		req = p9_client_rpc(clnt, P9_TWRITE, "dqU", fid->fid, offset,
+		/* Try a zero copy rpc for user write */
+		req = p9_client_zcrpc(clnt, P9_TWRITE, "dqU", fid->fid, offset,
 								rsize, udata);
 	if (IS_ERR(req)) {
 		err = PTR_ERR(req);
diff --git a/net/9p/trans_fd.c b/net/9p/trans_fd.c
index 078eb16..91b5a47 100644
--- a/net/9p/trans_fd.c
+++ b/net/9p/trans_fd.c
@@ -1012,6 +1012,7 @@  static struct p9_trans_module p9_tcp_trans = {
 	.create = p9_fd_create_tcp,
 	.close = p9_fd_close,
 	.request = p9_fd_request,
+	.zc_request = p9_no_zero_copy_request,
 	.cancel = p9_fd_cancel,
 	.owner = THIS_MODULE,
 };
diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c
index c8f3f72..576da62 100644
--- a/net/9p/trans_virtio.c
+++ b/net/9p/trans_virtio.c
@@ -446,6 +446,7 @@  static struct p9_trans_module p9_virtio_trans = {
 	.create = p9_virtio_create,
 	.close = p9_virtio_close,
 	.request = p9_virtio_request,
+	.zc_request = p9_virtio_zero_copy_request,
 	.cancel = p9_virtio_cancel,
 	.maxsize = PAGE_SIZE*16,
 	.def = 0,