git: 8e816fc2e98c - main - hn: Invoke the owned VF's transmit queue flush callback

The branch main has been updated by kbowling:

URL: https://cgit.FreeBSD.org/src/commit/?id=8e816fc2e98c8c0bf0b6fef3bd5f52bc03c843ce

commit 8e816fc2e98c8c0bf0b6fef3bd5f52bc03c843ce
Author:     Kevin Bowling <kbowling@FreeBSD.org>
AuthorDate: 2026-09-15 00:26:14 +0000
Commit:     Kevin Bowling <kbowling@FreeBSD.org>
CommitDate: 2026-09-15 02:02:26 +0000

    hn: Invoke the owned VF's transmit queue flush callback
    
    The generic if_qflush() only clears if_snd.  Calling it directly for a
    transparent VF bypasses the driver's callback and its private software
    transmit queues.  Add if_getqflushfn(), matching the existing callback
    accessors, and invoke the registered callback while hn_vf_lock protects
    the VF pointer.
    
    Flush an attached VF whenever transparent mode owns it, not only while
    the VF datapath is enabled.  Disabling transmit during handoff does not
    discard packets already queued to the VF.  This also covers the inactive
    interval after fallback.  Non-transparent VFs remain independently owned
    and are not flushed by hn.  Synthetic queue flushing is unchanged.
    
    MFC after:      2 weeks
    Sponsored by:   BBOX.io
---
 sys/dev/hyperv/netvsc/if_hn.c | 5 +++--
 sys/net/if.c                  | 6 ++++++
 sys/net/if_var.h              | 1 +
 3 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/sys/dev/hyperv/netvsc/if_hn.c b/sys/dev/hyperv/netvsc/if_hn.c
index e4774b285a15..72bef946b0d5 100644
--- a/sys/dev/hyperv/netvsc/if_hn.c
+++ b/sys/dev/hyperv/netvsc/if_hn.c
@@ -6240,8 +6240,9 @@ hn_xmit_qflush(if_t ifp)
 	if_qflush(ifp);
 
 	rm_rlock(&sc->hn_vf_lock, &pt);
-	if (sc->hn_xvf_flags & HN_XVFFLAG_ENABLED)
-		if_qflush(sc->hn_vf_ifp);
+	/* Transparent mode owns the VF's queues even while switching paths. */
+	if (hn_xpnt_vf && sc->hn_vf_ifp != NULL)
+		if_getqflushfn(sc->hn_vf_ifp)(sc->hn_vf_ifp);
 	rm_runlock(&sc->hn_vf_lock, &pt);
 }
 
diff --git a/sys/net/if.c b/sys/net/if.c
index 552ae04d3215..084d0ffb8a65 100644
--- a/sys/net/if.c
+++ b/sys/net/if.c
@@ -5087,6 +5087,12 @@ if_setqflushfn(if_t ifp, if_qflush_fn_t flush_fn)
 	ifp->if_qflush = flush_fn;
 }
 
+if_qflush_fn_t
+if_getqflushfn(if_t ifp)
+{
+	return (ifp->if_qflush);
+}
+
 void
 if_setsndtagallocfn(if_t ifp, if_snd_tag_alloc_t alloc_fn)
 {
diff --git a/sys/net/if_var.h b/sys/net/if_var.h
index 8297520f7607..6e2b7743aa00 100644
--- a/sys/net/if_var.h
+++ b/sys/net/if_var.h
@@ -738,6 +738,7 @@ if_start_fn_t if_getstartfn(if_t ifp);
 void if_settransmitfn(if_t ifp, if_transmit_fn_t);
 if_transmit_fn_t if_gettransmitfn(if_t ifp);
 void if_setqflushfn(if_t ifp, if_qflush_fn_t);
+if_qflush_fn_t if_getqflushfn(if_t ifp);
 void if_setgetcounterfn(if_t ifp, if_get_counter_t);
 void if_setsndtagallocfn(if_t ifp, if_snd_tag_alloc_t);
 void if_setdebugnet_methods(if_t, struct debugnet_methods *);