pcie_root_port: Add hotplug disabling option

Make hot-plug/hot-unplug on PCIe Root Ports optional to allow libvirt
manage it and restrict unplug for the whole machine. This is going to
prevent user-initiated unplug in guests (Windows mostly).
Hotplug is enabled by default.
Usage:
    -device pcie-root-port,hotplug=off,...

If you want to disable hot-unplug on some downstream ports of one
switch, disable hot-unplug on PCIe Root Port connected to the upstream
port as well as on the selected downstream ports.

Discussion related:
    https://lists.gnu.org/archive/html/qemu-devel/2020-02/msg00530.html

Signed-off-by: Julia Suvorova <[email protected]>
Message-Id: <20200226174607[email protected]>
Reviewed-by: Michael S. Tsirkin <[email protected]>
Signed-off-by: Michael S. Tsirkin <[email protected]>
Reviewed-by: Ján Tomko <[email protected]>

diff --git a/hw/pci-bridge/pcie_root_port.c b/hw/pci-bridge/pcie_root_port.c
index 0ba4e4dea45fb680329380e2b606899d56126330..f1cfe9d14aaf7927a1faf9e0c4c3cc9cefc2c54f 100644 (file)
--- a/hw/pci-bridge/pcie_root_port.c
+++ b/hw/pci-bridge/pcie_root_port.c
@@ -94,7 +94,7 @@ static void rp_realize(PCIDevice *d, Error **errp)
 
     pcie_cap_arifwd_init(d);
     pcie_cap_deverr_init(d);
-    pcie_cap_slot_init(d, s->slot);
+    pcie_cap_slot_init(d, s);
     pcie_cap_root_init(d);
 
     pcie_chassis_create(s->chassis);

diff --git a/hw/pci-bridge/xio3130_downstream.c b/hw/pci-bridge/xio3130_downstream.c
index 153a4acad27405c64554bd8a84197453a16d53d4..04aae72cd614d4d8eb9c8a3f023ec71323f09086 100644 (file)
--- a/hw/pci-bridge/xio3130_downstream.c
+++ b/hw/pci-bridge/xio3130_downstream.c
@@ -94,7 +94,7 @@ static void xio3130_downstream_realize(PCIDevice *d, Error **errp)
     }
     pcie_cap_flr_init(d);
     pcie_cap_deverr_init(d);
-    pcie_cap_slot_init(d, s->slot);
+    pcie_cap_slot_init(d, s);
     pcie_cap_arifwd_init(d);
 
     pcie_chassis_create(s->chassis);

diff --git a/hw/pci/pcie.c b/hw/pci/pcie.c
index 08718188bb7c71659837a2ea602caa117a643582..0eb3a2a5d231205d424acff6008c836f242e6ca2 100644 (file)
--- a/hw/pci/pcie.c
+++ b/hw/pci/pcie.c
@@ -495,7 +495,7 @@ void pcie_cap_slot_unplug_request_cb(HotplugHandler *hotplug_dev,
 
 /* pci express slot for pci express root/downstream port
    PCI express capability slot registers */
-void pcie_cap_slot_init(PCIDevice *dev, uint16_t slot)
+void pcie_cap_slot_init(PCIDevice *dev, PCIESlot *s)
 {
     uint32_t pos = dev->exp.exp_cap;
 
@@ -505,13 +505,16 @@ void pcie_cap_slot_init(PCIDevice *dev, uint16_t slot)
     pci_long_test_and_clear_mask(dev->config + pos + PCI_EXP_SLTCAP,
                                  ~PCI_EXP_SLTCAP_PSN);
     pci_long_test_and_set_mask(dev->config + pos + PCI_EXP_SLTCAP,
-                               (slot << PCI_EXP_SLTCAP_PSN_SHIFT) |
+                               (s->slot << PCI_EXP_SLTCAP_PSN_SHIFT) |
                                PCI_EXP_SLTCAP_EIP |
-                               PCI_EXP_SLTCAP_HPS |
-                               PCI_EXP_SLTCAP_HPC |
                                PCI_EXP_SLTCAP_PIP |
                                PCI_EXP_SLTCAP_AIP |
                                PCI_EXP_SLTCAP_ABP);
+    if (s->hotplug) {
+        pci_long_test_and_set_mask(dev->config + pos + PCI_EXP_SLTCAP,
+                                   PCI_EXP_SLTCAP_HPS |
+                                   PCI_EXP_SLTCAP_HPC);
+    }
 
     if (dev->cap_present & QEMU_PCIE_SLTCAP_PCP) {
         pci_long_test_and_set_mask(dev->config + pos + PCI_EXP_SLTCAP,

diff --git a/hw/pci/pcie_port.c b/hw/pci/pcie_port.c
index f8263cb306182a57620b24916fc467acaac87d1f..eb563ad4354f0da779ab04700c47e43c8843d1d3 100644 (file)
--- a/hw/pci/pcie_port.c
+++ b/hw/pci/pcie_port.c
@@ -147,6 +147,7 @@ static const TypeInfo pcie_port_type_info = {
 static Property pcie_slot_props[] = {
     DEFINE_PROP_UINT8("chassis", PCIESlot, chassis, 0),
     DEFINE_PROP_UINT16("slot", PCIESlot, slot, 0),
+    DEFINE_PROP_BOOL("hotplug", PCIESlot, hotplug, true),
     DEFINE_PROP_END_OF_LIST()
 };
 

diff --git a/include/hw/pci/pcie.h b/include/hw/pci/pcie.h
index 7064875835995d3a80a6faffc4385ff92bc6bfb9..14c58ebdb6ec1fd5dc3c8563fed9f76a58bbc434 100644 (file)
--- a/include/hw/pci/pcie.h
+++ b/include/hw/pci/pcie.h
@@ -104,7 +104,7 @@ void pcie_cap_deverr_reset(PCIDevice *dev);
 void pcie_cap_lnkctl_init(PCIDevice *dev);
 void pcie_cap_lnkctl_reset(PCIDevice *dev);
 
-void pcie_cap_slot_init(PCIDevice *dev, uint16_t slot);
+void pcie_cap_slot_init(PCIDevice *dev, PCIESlot *s);
 void pcie_cap_slot_reset(PCIDevice *dev);
 void pcie_cap_slot_get(PCIDevice *dev, uint16_t *slt_ctl, uint16_t *slt_sta);
 void pcie_cap_slot_write_config(PCIDevice *dev,

diff --git a/include/hw/pci/pcie_port.h b/include/hw/pci/pcie_port.h
index 4b3d254b08213e593456428374a72a2c521ff34e..caae57573bf688fcbf2f7e6e033f1de8360cbf27 100644 (file)
--- a/include/hw/pci/pcie_port.h
+++ b/include/hw/pci/pcie_port.h
@@ -55,6 +55,9 @@ struct PCIESlot {
 
     /* Disable ACS (really for a pcie_root_port) */
     bool        disable_acs;
+
+    /* Indicates whether hot-plug is enabled on the slot */
+    bool        hotplug;
     QLIST_ENTRY(PCIESlot) next;
 };