[PULL 19/20] pcie: fast unplug when slot power is off

["Michael S. Tsirkin" <mst@redhat.com>]

From: Gerd Hoffmann <kraxel@redhat.com>

In case the slot is powered off (and the power indicator turned off too)
we can unplug right away, without round-trip to the guest.

Also clear pending attention button press, there is nothing to care
about any more.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-Id: <20211111130859.1171890-6-kraxel@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 hw/pci/pcie.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/hw/pci/pcie.c b/hw/pci/pcie.c
index 959bf074b2..a930ac738a 100644
--- a/hw/pci/pcie.c
+++ b/hw/pci/pcie.c
@@ -560,6 +560,16 @@ void pcie_cap_slot_unplug_request_cb(HotplugHandler *hotplug_dev,
         return;
     }
 
+    if (((sltctl & PCI_EXP_SLTCTL_PIC) == PCI_EXP_SLTCTL_PWR_IND_OFF) &&
+        ((sltctl & PCI_EXP_SLTCTL_PCC) == PCI_EXP_SLTCTL_PWR_OFF)) {
+        /* slot is powered off -> unplug without round-trip to the guest */
+        pcie_cap_slot_do_unplug(hotplug_pdev);
+        hotplug_event_notify(hotplug_pdev);
+        pci_word_test_and_clear_mask(exp_cap + PCI_EXP_SLTSTA,
+                                     PCI_EXP_SLTSTA_ABP);
+        return;
+    }
+
     pcie_cap_slot_push_attention_button(hotplug_pdev);
 }
 
-- 
MST