x86: Unplug emulated disks and nics.

Add a xen_emul_unplug command line option to the kernel to unplug
xen emulated disks and nics.

Set the default value of xen_emul_unplug depending on whether or
not the Xen PV frontends and the Xen platform PCI driver have
been compiled for this kernel (modules or built-in are both OK).

The user can specify xen_emul_unplug=ignore to enable PV drivers on HVM
even if the host platform doesn't support unplug.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>

1 files changed, 49 insertions, 0 deletions

diff --git a/include/xen/platform_pci.h b/include/xen/platform_pci.h
new file mode 100644
index 000000000000..ce9d671c636c
--- /dev/null
+++ b/include/xen/platform_pci.h
@@ -0,0 +1,49 @@
+#ifndef _XEN_PLATFORM_PCI_H
+#define _XEN_PLATFORM_PCI_H
+
+#define XEN_IOPORT_MAGIC_VAL 0x49d2
+#define XEN_IOPORT_LINUX_PRODNUM 0x0003
+#define XEN_IOPORT_LINUX_DRVVER  0x0001
+
+#define XEN_IOPORT_BASE 0x10
+
+#define XEN_IOPORT_PLATFLAGS    (XEN_IOPORT_BASE + 0) /* 1 byte access (R/W) */
+#define XEN_IOPORT_MAGIC        (XEN_IOPORT_BASE + 0) /* 2 byte access (R) */
+#define XEN_IOPORT_UNPLUG       (XEN_IOPORT_BASE + 0) /* 2 byte access (W) */
+#define XEN_IOPORT_DRVVER       (XEN_IOPORT_BASE + 0) /* 4 byte access (W) */
+
+#define XEN_IOPORT_SYSLOG       (XEN_IOPORT_BASE + 2) /* 1 byte access (W) */
+#define XEN_IOPORT_PROTOVER     (XEN_IOPORT_BASE + 2) /* 1 byte access (R) */
+#define XEN_IOPORT_PRODNUM      (XEN_IOPORT_BASE + 2) /* 2 byte access (W) */
+
+#define XEN_UNPLUG_ALL_IDE_DISKS 1
+#define XEN_UNPLUG_ALL_NICS 2
+#define XEN_UNPLUG_AUX_IDE_DISKS 4
+#define XEN_UNPLUG_ALL 7
+#define XEN_UNPLUG_IGNORE 8
+
+static inline int xen_must_unplug_nics(void) {
+#if (defined(CONFIG_XEN_NETDEV_FRONTEND) || \
+                defined(CONFIG_XEN_NETDEV_FRONTEND_MODULE)) && \
+                (defined(CONFIG_XEN_PLATFORM_PCI) || \
+                 defined(CONFIG_XEN_PLATFORM_PCI_MODULE))
+        return 1;
+#else
+        return 0;
+#endif
+}
+
+static inline int xen_must_unplug_disks(void) {
+#if (defined(CONFIG_XEN_BLKDEV_FRONTEND) || \
+                defined(CONFIG_XEN_BLKDEV_FRONTEND_MODULE)) && \
+                (defined(CONFIG_XEN_PLATFORM_PCI) || \
+                 defined(CONFIG_XEN_PLATFORM_PCI_MODULE))
+        return 1;
+#else
+        return 0;
+#endif
+}
+
+extern int xen_platform_pci_unplug;
+
+#endif /* _XEN_PLATFORM_PCI_H */