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@xxxxxxxxxxxxxxxxxx> --- net/9p/client.c | 26 ++++++++++++++++++-------- net/9p/protocol.c | 21 +++++++++++++++++++++ 2 files changed, 39 insertions(+), 8 deletions(-) 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 @@ p9_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset, 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_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset, 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); diff --git a/net/9p/protocol.c b/net/9p/protocol.c index 5936c50..7bca242 100644 --- a/net/9p/protocol.c +++ b/net/9p/protocol.c @@ -114,6 +114,17 @@ pdu_write_u(struct p9_fcall *pdu, const char __user *udata, size_t size) return size - len; } +static size_t +pdu_write_urw(struct p9_fcall *pdu, const char *kdata, const char __user *udata, + size_t size) +{ + BUG_ON(pdu->size > P9_IOHDRSZ); + pdu->pubuf = (char __user *)udata; + pdu->pkbuf = (char *)kdata; + pdu->pbuf_size = size; + return 0; +} + /* b - int8_t w - int16_t @@ -445,6 +456,16 @@ p9pdu_vwritef(struct p9_fcall *pdu, int proto_version, const char *fmt, errcode = -EFAULT; } break; + case 'E':{ + int32_t cnt = va_arg(ap, int32_t); + const char *k = va_arg(ap, const void *); + const char *u = va_arg(ap, const void *); + errcode = p9pdu_writef(pdu, proto_version, "d", + cnt); + if (!errcode && pdu_write_urw(pdu, k, u, cnt)) + errcode = -EFAULT; + } + break; case 'U':{ int32_t count = va_arg(ap, int32_t); const char __user *udata = -- 1.6.5.2 -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html