nvme/tcp: handle tls partially sent records in write_space()

With TLS enabled, records that are encrypted and appended to TLS TX
list can fail to see a retry if the underlying TCP socket is busy, for
example, hitting an EAGAIN from tcp_sendmsg_locked(). This is not known
to the NVMe TCP driver, as the TLS layer successfully generated a record.

Typically, the TLS write_space() callback would ensure such records are
retried, but in the NVMe TCP Host driver, write_space() invokes
nvme_tcp_write_space(). This causes a partially sent record in the TLS TX
list to timeout after not being retried.

This patch fixes the above by calling queue->write_space(), which calls
into the TLS layer to retry any pending records.

Fixes: be8e82caa685 ("nvme-tcp: enable TLS handshake upcall")
Signed-off-by: Wilfred Mallawa <wilfred.mallawa@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c
index 1413788ca7d52389db0b36d4acc086a7e80ebeeb..9a96df1a511c021b4b322bf54dc489cc400f7961 100644 (file)
--- a/drivers/nvme/host/tcp.c
+++ b/drivers/nvme/host/tcp.c
@@ -1081,6 +1081,9 @@ static void nvme_tcp_write_space(struct sock *sk)
        queue = sk->sk_user_data;
        if (likely(queue && sk_stream_is_writeable(sk))) {
                clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
+               /* Ensure pending TLS partial records are retried */
+               if (nvme_tcp_queue_tls(queue))
+                       queue->write_space(sk);
                queue_work_on(queue->io_cpu, nvme_tcp_wq, &queue->io_work);
        }
        read_unlock_bh(&sk->sk_callback_lock);