/**
* xs_udp_data_ready - "data ready" callback for UDP sockets
* @sk: socket with data to read
* @len: how much data to read
*
*/
static void xs_udp_data_ready(struct sock *sk, int len)
{
struct rpc_task *task;
struct rpc_xprt *xprt;
struct rpc_rqst *rovr;
struct sk_buff *skb;
int err, repsize, copied;
u32 _xid, *xp;
read_lock(&sk->sk_callback_lock);
dprintk("RPC: xs_udp_data_ready...\n");
if (!(xprt = xprt_from_sock(sk)))
goto out;
if ((skb = skb_recv_datagram(sk, 0, 1, &err)) == NULL)
goto out;
if (xprt->shutdown)
goto dropit;
repsize = skb->len - sizeof(struct udphdr);
if (repsize < 4) {
dprintk("RPC: impossible RPC reply size %d!\n", repsize);
goto dropit;
}
/* Copy the XID from the skb... */
xp = skb_header_pointer(skb, sizeof(struct udphdr),
sizeof(_xid), &_xid);
if (xp == NULL)
goto dropit;
/* Look up and lock the request corresponding to the given XID */
spin_lock(&xprt->transport_lock);
rovr = xprt_lookup_rqst(xprt, *xp);
if (!rovr)
goto out_unlock;
task = rovr->rq_task;
if ((copied = rovr->rq_private_buf.buflen) > repsize)
copied = repsize;
/* Suck it into the iovec, verify checksum if not done by hw. */
if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb))
goto out_unlock;
/* Something worked... */
dst_confirm(skb->dst);
xprt_adjust_cwnd(task, copied);
xprt_update_rtt(task);
xprt_complete_rqst(task, copied);
out_unlock:
spin_unlock(&xprt->transport_lock);
dropit:
skb_free_datagram(sk, skb);
out:
read_unlock(&sk->sk_callback_lock);
}
int svc_rdma_handle_bc_reply(struct rpc_xprt *xprt, struct rpcrdma_msg *rmsgp,
struct xdr_buf *rcvbuf)
{
struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
struct kvec *dst, *src = &rcvbuf->head[0];
struct rpc_rqst *req;
unsigned long cwnd;
u32 credits;
size_t len;
__be32 xid;
__be32 *p;
int ret;
p = (__be32 *)src->iov_base;
len = src->iov_len;
xid = rmsgp->rm_xid;
#ifdef SVCRDMA_BACKCHANNEL_DEBUG
pr_info("%s: xid=%08x, length=%zu\n",
__func__, be32_to_cpu(xid), len);
pr_info("%s: RPC/RDMA: %*ph\n",
__func__, (int)RPCRDMA_HDRLEN_MIN, rmsgp);
pr_info("%s: RPC: %*ph\n",
__func__, (int)len, p);
#endif
ret = -EAGAIN;
if (src->iov_len < 24)
goto out_shortreply;
spin_lock_bh(&xprt->transport_lock);
req = xprt_lookup_rqst(xprt, xid);
if (!req)
goto out_notfound;
dst = &req->rq_private_buf.head[0];
memcpy(&req->rq_private_buf, &req->rq_rcv_buf, sizeof(struct xdr_buf));
if (dst->iov_len < len)
goto out_unlock;
memcpy(dst->iov_base, p, len);
credits = be32_to_cpu(rmsgp->rm_credit);
if (credits == 0)
credits = 1; /* don't deadlock */
else if (credits > r_xprt->rx_buf.rb_bc_max_requests)
credits = r_xprt->rx_buf.rb_bc_max_requests;
cwnd = xprt->cwnd;
xprt->cwnd = credits << RPC_CWNDSHIFT;
if (xprt->cwnd > cwnd)
xprt_release_rqst_cong(req->rq_task);
ret = 0;
xprt_complete_rqst(req->rq_task, rcvbuf->len);
rcvbuf->len = 0;
out_unlock:
spin_unlock_bh(&xprt->transport_lock);
out:
return ret;
out_shortreply:
dprintk("svcrdma: short bc reply: xprt=%p, len=%zu\n",
xprt, src->iov_len);
goto out;
out_notfound:
dprintk("svcrdma: unrecognized bc reply: xprt=%p, xid=%08x\n",
xprt, be32_to_cpu(xid));
goto out_unlock;
}
static inline void xs_tcp_read_request(struct rpc_xprt *xprt, skb_reader_t *desc)
{
struct rpc_rqst *req;
struct xdr_buf *rcvbuf;
size_t len;
ssize_t r;
/* Find and lock the request corresponding to this xid */
spin_lock(&xprt->transport_lock);
req = xprt_lookup_rqst(xprt, xprt->tcp_xid);
if (!req) {
xprt->tcp_flags &= ~XPRT_COPY_DATA;
dprintk("RPC: XID %08x request not found!\n",
ntohl(xprt->tcp_xid));
spin_unlock(&xprt->transport_lock);
return;
}
rcvbuf = &req->rq_private_buf;
len = desc->count;
if (len > xprt->tcp_reclen - xprt->tcp_offset) {
skb_reader_t my_desc;
len = xprt->tcp_reclen - xprt->tcp_offset;
memcpy(&my_desc, desc, sizeof(my_desc));
my_desc.count = len;
r = xdr_partial_copy_from_skb(rcvbuf, xprt->tcp_copied,
&my_desc, xs_tcp_copy_data);
desc->count -= r;
desc->offset += r;
} else
r = xdr_partial_copy_from_skb(rcvbuf, xprt->tcp_copied,
desc, xs_tcp_copy_data);
if (r > 0) {
xprt->tcp_copied += r;
xprt->tcp_offset += r;
}
if (r != len) {
/* Error when copying to the receive buffer,
* usually because we weren't able to allocate
* additional buffer pages. All we can do now
* is turn off XPRT_COPY_DATA, so the request
* will not receive any additional updates,
* and time out.
* Any remaining data from this record will
* be discarded.
*/
xprt->tcp_flags &= ~XPRT_COPY_DATA;
dprintk("RPC: XID %08x truncated request\n",
ntohl(xprt->tcp_xid));
dprintk("RPC: xprt = %p, tcp_copied = %lu, tcp_offset = %u, tcp_reclen = %u\n",
xprt, xprt->tcp_copied, xprt->tcp_offset, xprt->tcp_reclen);
goto out;
}
dprintk("RPC: XID %08x read %Zd bytes\n",
ntohl(xprt->tcp_xid), r);
dprintk("RPC: xprt = %p, tcp_copied = %lu, tcp_offset = %u, tcp_reclen = %u\n",
xprt, xprt->tcp_copied, xprt->tcp_offset, xprt->tcp_reclen);
if (xprt->tcp_copied == req->rq_private_buf.buflen)
xprt->tcp_flags &= ~XPRT_COPY_DATA;
else if (xprt->tcp_offset == xprt->tcp_reclen) {
if (xprt->tcp_flags & XPRT_LAST_FRAG)
xprt->tcp_flags &= ~XPRT_COPY_DATA;
}
out:
if (!(xprt->tcp_flags & XPRT_COPY_DATA))
xprt_complete_rqst(req->rq_task, xprt->tcp_copied);
spin_unlock(&xprt->transport_lock);
xs_tcp_check_recm(xprt);
}