@@ -1819,6 +1819,13 @@ All numbers specified must be hexadecimal ones.
This option can be specified more than once (up to 8 times at present).
+### pci-passthrough (arm)
+> `= <boolean>`
+
+> Default: `false`
+
+Flag to enable or disable support for PCI passthrough
+
### pcid (x86)
> `= <boolean> | xpti=<bool>`
@@ -16,6 +16,7 @@
#include <xen/device_tree.h>
#include <xen/errno.h>
#include <xen/init.h>
+#include <xen/param.h>
#include <xen/pci.h>
/*
@@ -62,8 +63,19 @@ static int __init acpi_pci_init(void)
}
#endif
+/* By default pci passthrough is disabled. */
+bool __read_mostly pci_passthrough_enabled;
+boolean_param("pci-passthrough", pci_passthrough_enabled);
+
static int __init pci_init(void)
{
+ /*
+ * Enable PCI passthrough when has been enabled explicitly
+ * (pci-passthrough=on).
+ */
+ if ( !pci_passthrough_enabled )
+ return 0;
+
pci_segments_init();
if ( acpi_disabled )
@@ -18,6 +18,9 @@ ret_t pci_physdev_op(int cmd, XEN_GUEST_HANDLE_PARAM(void) arg)
struct pci_dev_info pdev_info;
nodeid_t node = NUMA_NO_NODE;
+ if ( !is_pci_passthrough_enabled() )
+ return -EOPNOTSUPP;
+
ret = -EFAULT;
if ( copy_from_guest(&add, arg, 1) != 0 )
break;
@@ -53,6 +56,9 @@ ret_t pci_physdev_op(int cmd, XEN_GUEST_HANDLE_PARAM(void) arg)
case PHYSDEVOP_pci_device_remove: {
struct physdev_pci_device dev;
+ if ( !is_pci_passthrough_enabled() )
+ return -EOPNOTSUPP;
+
ret = -EFAULT;
if ( copy_from_guest(&dev, arg, 1) != 0 )
break;
@@ -19,14 +19,25 @@
#define pci_to_dev(pcidev) (&(pcidev)->arch.dev)
+extern bool_t pci_passthrough_enabled;
+
/* Arch pci dev struct */
struct arch_pci_dev {
struct device dev;
};
+static always_inline bool is_pci_passthrough_enabled(void)
+{
+ return pci_passthrough_enabled;
+}
#else /*!CONFIG_HAS_PCI*/
struct arch_pci_dev { };
+static always_inline bool is_pci_passthrough_enabled(void)
+{
+ return false;
+}
+
#endif /*!CONFIG_HAS_PCI*/
#endif /* __ARM_PCI_H__ */
@@ -32,4 +32,10 @@ bool_t pci_ro_mmcfg_decode(unsigned long mfn, unsigned int *seg,
extern int pci_mmcfg_config_num;
extern struct acpi_mcfg_allocation *pci_mmcfg_config;
+/* Unlike ARM, PCI passthrough is always enabled for x86. */
+static always_inline bool is_pci_passthrough_enabled(void)
+{
+ return true;
+}
+
#endif /* __X86_PCI_H__ */