usb: Move clearing of queue on halt to the core

hcds which queue up more then one packet at once (uhci, ehci and xhci),
must clear the queue after an error which has caused the queue to halt.

Currently this is handled as a special case inside the hcd code, this
patch instead adds an USB_RET_REMOVE_FROM_QUEUE packet result code, teaches
the 3 hcds about this and moves the clearing of the queue on a halt into
the USB core.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

diff --git a/hw/usb.h b/hw/usb.h
index 435cd42a03b06d13e72fd8043794dfa4327db040..ead03c9f6b6bb0084983d4eb9f795cbce32f432e 100644 (file)
--- a/hw/usb.h
+++ b/hw/usb.h
@@ -45,6 +45,7 @@
 #define USB_RET_IOERROR           (-5)
 #define USB_RET_ASYNC             (-6)
 #define USB_RET_ADD_TO_QUEUE      (-7)
+#define USB_RET_REMOVE_FROM_QUEUE (-8)
 
 #define USB_SPEED_LOW   0
 #define USB_SPEED_FULL  1

diff --git a/hw/usb/core.c b/hw/usb/core.c
index 014e3ac0902842106049270a170dac3900cda2cb..5a97a0e412879689d24320b50362bef6854ba02a 100644 (file)
--- a/hw/usb/core.c
+++ b/hw/usb/core.c
@@ -442,8 +442,14 @@ void usb_packet_complete(USBDevice *dev, USBPacket *p)
     usb_packet_check_state(p, USB_PACKET_ASYNC);
     usb_packet_complete_one(dev, p);
 
-    while (!ep->halted && !QTAILQ_EMPTY(&ep->queue)) {
+    while (!QTAILQ_EMPTY(&ep->queue)) {
         p = QTAILQ_FIRST(&ep->queue);
+        if (ep->halted) {
+            /* Empty the queue on a halt */
+            p->result = USB_RET_REMOVE_FROM_QUEUE;
+            dev->port->ops->complete(dev->port, p);
+            continue;
+        }
         if (p->state == USB_PACKET_ASYNC) {
             break;
         }

diff --git a/hw/usb/hcd-ehci.c b/hw/usb/hcd-ehci.c
index d11311e87f8a9d45ff0c7410c2f989e2c61419b0..74a2587eba0ec341f9af476cd24c3b520986cfb5 100644 (file)
--- a/hw/usb/hcd-ehci.c
+++ b/hw/usb/hcd-ehci.c
@@ -1457,8 +1457,15 @@ static void ehci_async_complete_packet(USBPort *port, USBPacket *packet)
     }
 
     p = container_of(packet, EHCIPacket, packet);
-    trace_usb_ehci_packet_action(p->queue, p, "wakeup");
     assert(p->async == EHCI_ASYNC_INFLIGHT);
+
+    if (packet->result == USB_RET_REMOVE_FROM_QUEUE) {
+        trace_usb_ehci_packet_action(p->queue, p, "remove");
+        ehci_free_packet(p);
+        return;
+    }
+
+    trace_usb_ehci_packet_action(p->queue, p, "wakeup");
     p->async = EHCI_ASYNC_FINISHED;
     p->usb_status = packet->result;
 
@@ -2216,19 +2223,6 @@ static int ehci_state_writeback(EHCIQueue *q)
      * bit is clear.
      */
     if (q->qh.token & QTD_TOKEN_HALT) {
-        /*
-         * We should not do any further processing on a halted queue!
-         * This is esp. important for bulk endpoints with pipelining enabled
-         * (redirection to a real USB device), where we must cancel all the
-         * transfers after this one so that:
-         * 1) If they've completed already, they are not processed further
-         *    causing more stalls, originating from the same failed transfer
-         * 2) If still in flight, they are cancelled before the guest does
-         *    a clear stall, otherwise the guest and device can loose sync!
-         */
-        while ((p = QTAILQ_FIRST(&q->packets)) != NULL) {
-            ehci_free_packet(p);
-        }
         ehci_set_state(q->ehci, q->async, EST_HORIZONTALQH);
         again = 1;
     } else {

diff --git a/hw/usb/hcd-uhci.c b/hw/usb/hcd-uhci.c
index 46e544b910852854a49a1905e3e81694a755bdc0..00dc9d538f8bcbed6aa5143734133626b39a6df2 100644 (file)
--- a/hw/usb/hcd-uhci.c
+++ b/hw/usb/hcd-uhci.c
@@ -744,22 +744,6 @@ static int uhci_complete_td(UHCIState *s, UHCI_TD *td, UHCIAsync *async, uint32_
     return TD_RESULT_COMPLETE;
 
 out:
-    /*
-     * We should not do any further processing on a queue with errors!
-     * This is esp. important for bulk endpoints with pipelining enabled
-     * (redirection to a real USB device), where we must cancel all the
-     * transfers after this one so that:
-     * 1) If they've completed already, they are not processed further
-     *    causing more stalls, originating from the same failed transfer
-     * 2) If still in flight, they are cancelled before the guest does
-     *    a clear stall, otherwise the guest and device can loose sync!
-     */
-    while (!QTAILQ_EMPTY(&async->queue->asyncs)) {
-        UHCIAsync *as = QTAILQ_FIRST(&async->queue->asyncs);
-        uhci_async_unlink(as);
-        uhci_async_cancel(as);
-    }
-
     switch(ret) {
     case USB_RET_STALL:
         td->ctrl |= TD_CTRL_STALL;
@@ -918,6 +902,12 @@ static void uhci_async_complete(USBPort *port, USBPacket *packet)
     UHCIAsync *async = container_of(packet, UHCIAsync, packet);
     UHCIState *s = async->queue->uhci;
 
+    if (packet->result == USB_RET_REMOVE_FROM_QUEUE) {
+        uhci_async_unlink(async);
+        uhci_async_cancel(async);
+        return;
+    }
+
     if (async->isoc) {
         UHCI_TD td;
         uint32_t link = async->td;

diff --git a/hw/usb/hcd-xhci.c b/hw/usb/hcd-xhci.c
index e8929a07851329d385721040dd05f54a55d13446..1f437cc15f49446cab5d3a2ec41cfcff742d092b 100644 (file)
--- a/hw/usb/hcd-xhci.c
+++ b/hw/usb/hcd-xhci.c
@@ -2839,6 +2839,10 @@ static void xhci_complete(USBPort *port, USBPacket *packet)
 {
     XHCITransfer *xfer = container_of(packet, XHCITransfer, packet);
 
+    if (packet->result == USB_RET_REMOVE_FROM_QUEUE) {
+        xhci_ep_nuke_one_xfer(xfer);
+        return;
+    }
     xhci_complete_packet(xfer, packet->result);
     xhci_kick_ep(xfer->xhci, xfer->slotid, xfer->epid);
 }