git: 87bb5ed606fc - main - cxgbei: Use hardware RX flow control for offloaded iSCSI connections.

[John Baldwin]

The branch main has been updated by jhb:

URL: https://cgit.FreeBSD.org/src/commit/?id=87bb5ed606fc02f6520bbb8f9dfe2bc834a50d4d

commit 87bb5ed606fc02f6520bbb8f9dfe2bc834a50d4d
Author:     John Baldwin <jhb at FreeBSD.org>
AuthorDate: 2021-05-14 19:16:51 +0000
Commit:     John Baldwin <jhb at FreeBSD.org>
CommitDate: 2021-05-14 19:16:51 +0000

    cxgbei: Use hardware RX flow control for offloaded iSCSI connections.
    
    Forthcoming T6 iSCSI DDP support requires hardware RX flow control.
    
    Sponsored by:   Chelsio Communications
    Differential Revision:  https://reviews.freebsd.org/D29905
---
 sys/dev/cxgbe/cxgbei/cxgbei.c     | 8 ++++----
 sys/dev/cxgbe/cxgbei/icl_cxgbei.c | 3 +++
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/sys/dev/cxgbe/cxgbei/cxgbei.c b/sys/dev/cxgbe/cxgbei/cxgbei.c
index 07f704752305..7027e6428515 100644
--- a/sys/dev/cxgbe/cxgbei/cxgbei.c
+++ b/sys/dev/cxgbe/cxgbei/cxgbei.c
@@ -315,13 +315,13 @@ do_rx_iscsi_ddp(struct sge_iq *iq, const struct rss_header *rss, struct mbuf *m)
 
 	tp = intotcpcb(inp);
 	MPASS(icp->icp_seq == tp->rcv_nxt);
-	MPASS(tp->rcv_wnd >= pdu_len);
 	tp->rcv_nxt += pdu_len;
-	tp->rcv_wnd -= pdu_len;
 	tp->t_rcvtime = ticks;
 
-	/* update rx credits */
-	t4_rcvd(&toep->td->tod, tp);	/* XXX: sc->tom_softc.tod */
+	/*
+	 * Don't update the window size or return credits since RX
+	 * flow control is disabled.
+	 */
 
 	so = inp->inp_socket;
 	sb = &so->so_rcv;
diff --git a/sys/dev/cxgbe/cxgbei/icl_cxgbei.c b/sys/dev/cxgbe/cxgbei/icl_cxgbei.c
index 4e168a33e2ca..9ee31616b873 100644
--- a/sys/dev/cxgbe/cxgbei/icl_cxgbei.c
+++ b/sys/dev/cxgbe/cxgbei/icl_cxgbei.c
@@ -591,6 +591,9 @@ set_ulp_mode_iscsi(struct adapter *sc, struct toepcb *toep, u_int ulp_submode)
 	t4_set_tcb_field(sc, toep->ctrlq, toep, W_TCB_ULP_TYPE,
 	    V_TCB_ULP_TYPE(M_TCB_ULP_TYPE) | V_TCB_ULP_RAW(M_TCB_ULP_RAW), val,
 	    0, 0);
+
+	val = V_TF_RX_FLOW_CONTROL_DISABLE(1ULL);
+	t4_set_tcb_field(sc, toep->ctrlq, toep, W_TCB_T_FLAGS, val, val, 0, 0);
 }
 
 /*