[net/9p] Read side zerocopy changes for 9P2000.L protocol.
Modify p9_client_read() to check the transport preference and act accordingly.
If the preference is P9_TRANS_PREF_PAYLOAD_SEP, send the payload
separately instead of putting it directly on PDU.
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
diff --git a/net/9p/client.c b/net/9p/client.c
index a848bca..82079f9 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -1270,7 +1270,15 @@
if (count < rsize)
rsize = count;
- req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset, rsize);
+ /* Don't bother zerocopy form small IO (< 1024) */
+ if (((clnt->trans_mod->pref & P9_TRANS_PREF_PAYLOAD_MASK) ==
+ P9_TRANS_PREF_PAYLOAD_SEP) && (rsize > 1024)) {
+ req = p9_client_rpc(clnt, P9_TREAD, "dqE", fid->fid, offset,
+ rsize, data, udata);
+ } else {
+ req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset,
+ rsize);
+ }
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto error;
@@ -1284,13 +1292,15 @@
P9_DPRINTK(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
- if (data) {
- memmove(data, dataptr, count);
- } else {
- err = copy_to_user(udata, dataptr, count);
- if (err) {
- err = -EFAULT;
- goto free_and_error;
+ if (!req->tc->pbuf_size) {
+ if (data) {
+ memmove(data, dataptr, count);
+ } else {
+ err = copy_to_user(udata, dataptr, count);
+ if (err) {
+ err = -EFAULT;
+ goto free_and_error;
+ }
}
}
p9_free_req(clnt, req);