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authorStefano Stabellini <stefano.stabellini@eu.citrix.com>2010-05-14 12:44:30 +0100
committerJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>2010-07-26 23:13:25 -0700
commitc1c5413ad58cb73267d328e6020268aa2e50d8ca (patch)
treef2c66141ab8d9fdb7b16a13d4d510ad09b2430ed /arch/x86/xen
parent409771d258e9dd71c30f3c9520fd2b796ffc40f0 (diff)
downloadlinux-linaro-android-c1c5413ad58cb73267d328e6020268aa2e50d8ca.tar.gz
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>
Diffstat (limited to 'arch/x86/xen')
-rw-r--r--arch/x86/xen/Makefile2
-rw-r--r--arch/x86/xen/enlighten.c1
-rw-r--r--arch/x86/xen/platform-pci-unplug.c135
-rw-r--r--arch/x86/xen/xen-ops.h1
4 files changed, 138 insertions, 1 deletions
diff --git a/arch/x86/xen/Makefile b/arch/x86/xen/Makefile
index 3bb4fc21f4f..93095468598 100644
--- a/arch/x86/xen/Makefile
+++ b/arch/x86/xen/Makefile
@@ -12,7 +12,7 @@ CFLAGS_mmu.o := $(nostackp)
obj-y := enlighten.o setup.o multicalls.o mmu.o irq.o \
time.o xen-asm.o xen-asm_$(BITS).o \
- grant-table.o suspend.o
+ grant-table.o suspend.o platform-pci-unplug.o
obj-$(CONFIG_SMP) += smp.o
obj-$(CONFIG_PARAVIRT_SPINLOCKS)+= spinlock.o
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index a9017296388..157c93b62dd 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -1314,6 +1314,7 @@ static void __init xen_hvm_guest_init(void)
if (xen_feature(XENFEAT_hvm_callback_vector))
xen_have_vector_callback = 1;
register_cpu_notifier(&xen_hvm_cpu_notifier);
+ xen_unplug_emulated_devices();
have_vcpu_info_placement = 0;
x86_init.irqs.intr_init = xen_init_IRQ;
xen_hvm_init_time_ops();
diff --git a/arch/x86/xen/platform-pci-unplug.c b/arch/x86/xen/platform-pci-unplug.c
new file mode 100644
index 00000000000..2f7f3fb3477
--- /dev/null
+++ b/arch/x86/xen/platform-pci-unplug.c
@@ -0,0 +1,135 @@
+/******************************************************************************
+ * platform-pci-unplug.c
+ *
+ * Xen platform PCI device driver
+ * Copyright (c) 2010, Citrix
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/module.h>
+
+#include <xen/platform_pci.h>
+
+#define XEN_PLATFORM_ERR_MAGIC -1
+#define XEN_PLATFORM_ERR_PROTOCOL -2
+#define XEN_PLATFORM_ERR_BLACKLIST -3
+
+/* store the value of xen_emul_unplug after the unplug is done */
+int xen_platform_pci_unplug;
+EXPORT_SYMBOL_GPL(xen_platform_pci_unplug);
+static int xen_emul_unplug;
+
+static int __init check_platform_magic(void)
+{
+ short magic;
+ char protocol;
+
+ magic = inw(XEN_IOPORT_MAGIC);
+ if (magic != XEN_IOPORT_MAGIC_VAL) {
+ printk(KERN_ERR "Xen Platform PCI: unrecognised magic value\n");
+ return XEN_PLATFORM_ERR_MAGIC;
+ }
+
+ protocol = inb(XEN_IOPORT_PROTOVER);
+
+ printk(KERN_DEBUG "Xen Platform PCI: I/O protocol version %d\n",
+ protocol);
+
+ switch (protocol) {
+ case 1:
+ outw(XEN_IOPORT_LINUX_PRODNUM, XEN_IOPORT_PRODNUM);
+ outl(XEN_IOPORT_LINUX_DRVVER, XEN_IOPORT_DRVVER);
+ if (inw(XEN_IOPORT_MAGIC) != XEN_IOPORT_MAGIC_VAL) {
+ printk(KERN_ERR "Xen Platform: blacklisted by host\n");
+ return XEN_PLATFORM_ERR_BLACKLIST;
+ }
+ break;
+ default:
+ printk(KERN_WARNING "Xen Platform PCI: unknown I/O protocol version");
+ return XEN_PLATFORM_ERR_PROTOCOL;
+ }
+
+ return 0;
+}
+
+void __init xen_unplug_emulated_devices(void)
+{
+ int r;
+
+ /* check the version of the xen platform PCI device */
+ r = check_platform_magic();
+ /* If the version matches enable the Xen platform PCI driver.
+ * Also enable the Xen platform PCI driver if the version is really old
+ * and the user told us to ignore it. */
+ if (r && !(r == XEN_PLATFORM_ERR_MAGIC &&
+ (xen_emul_unplug & XEN_UNPLUG_IGNORE)))
+ return;
+ /* 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). */
+ if (!xen_emul_unplug) {
+ if (xen_must_unplug_nics()) {
+ printk(KERN_INFO "Netfront and the Xen platform PCI driver have "
+ "been compiled for this kernel: unplug emulated NICs.\n");
+ xen_emul_unplug |= XEN_UNPLUG_ALL_NICS;
+ }
+ if (xen_must_unplug_disks()) {
+ printk(KERN_INFO "Blkfront and the Xen platform PCI driver have "
+ "been compiled for this kernel: unplug emulated disks.\n"
+ "You might have to change the root device\n"
+ "from /dev/hd[a-d] to /dev/xvd[a-d]\n"
+ "in your root= kernel command line option\n");
+ xen_emul_unplug |= XEN_UNPLUG_ALL_IDE_DISKS;
+ }
+ }
+ /* Now unplug the emulated devices */
+ if (!(xen_emul_unplug & XEN_UNPLUG_IGNORE))
+ outw(xen_emul_unplug, XEN_IOPORT_UNPLUG);
+ xen_platform_pci_unplug = xen_emul_unplug;
+}
+
+static int __init parse_xen_emul_unplug(char *arg)
+{
+ char *p, *q;
+ int l;
+
+ for (p = arg; p; p = q) {
+ q = strchr(p, ',');
+ if (q) {
+ l = q - p;
+ q++;
+ } else {
+ l = strlen(p);
+ }
+ if (!strncmp(p, "all", l))
+ xen_emul_unplug |= XEN_UNPLUG_ALL;
+ else if (!strncmp(p, "ide-disks", l))
+ xen_emul_unplug |= XEN_UNPLUG_ALL_IDE_DISKS;
+ else if (!strncmp(p, "aux-ide-disks", l))
+ xen_emul_unplug |= XEN_UNPLUG_AUX_IDE_DISKS;
+ else if (!strncmp(p, "nics", l))
+ xen_emul_unplug |= XEN_UNPLUG_ALL_NICS;
+ else if (!strncmp(p, "ignore", l))
+ xen_emul_unplug |= XEN_UNPLUG_IGNORE;
+ else
+ printk(KERN_WARNING "unrecognised option '%s' "
+ "in parameter 'xen_emul_unplug'\n", p);
+ }
+ return 0;
+}
+early_param("xen_emul_unplug", parse_xen_emul_unplug);
diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h
index 089d18923d2..ed776949024 100644
--- a/arch/x86/xen/xen-ops.h
+++ b/arch/x86/xen/xen-ops.h
@@ -40,6 +40,7 @@ void xen_vcpu_restore(void);
void xen_callback_vector(void);
void xen_hvm_init_shared_info(void);
+void __init xen_unplug_emulated_devices(void);
void __init xen_build_dynamic_phys_to_machine(void);