Merge branch 'stable/xen-pcifront-0.8.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

  and branch 'for-linus' of git://xenbits.xen.org/people/sstabellini/linux-pvhvm

* 'for-linus' of git://xenbits.xen.org/people/sstabellini/linux-pvhvm:
  xen: register xen pci notifier
  xen: initialize cpu masks for pv guests in xen_smp_init
  xen: add a missing #include to arch/x86/pci/xen.c
  xen: mask the MTRR feature from the cpuid
  xen: make hvc_xen console work for dom0.
  xen: add the direct mapping area for ISA bus access
  xen: Initialize xenbus for dom0.
  xen: use vcpu_ops to setup cpu masks
  xen: map a dummy page for local apic and ioapic in xen_set_fixmap
  xen: remap MSIs into pirqs when running as initial domain
  xen: remap GSIs as pirqs when running as initial domain
  xen: introduce XEN_DOM0 as a silent option
  xen: map MSIs into pirqs
  xen: support GSI -> pirq remapping in PV on HVM guests
  xen: add xen hvm acpi_register_gsi variant
  acpi: use indirect call to register gsi in different modes
  xen: implement xen_hvm_register_pirq
  xen: get the maximum number of pirqs from xen
  xen: support pirq != irq

* 'stable/xen-pcifront-0.8.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: (27 commits)
  X86/PCI: Remove the dependency on isapnp_disable.
  xen: Update Makefile with CONFIG_BLOCK dependency for biomerge.c
  MAINTAINERS: Add myself to the Xen Hypervisor Interface and remove Chris Wright.
  x86: xen: Sanitse irq handling (part two)
  swiotlb-xen: On x86-32 builts, select SWIOTLB instead of depending on it.
  MAINTAINERS: Add myself for Xen PCI and Xen SWIOTLB maintainer.
  xen/pci: Request ACS when Xen-SWIOTLB is activated.
  xen-pcifront: Xen PCI frontend driver.
  xenbus: prevent warnings on unhandled enumeration values
  xenbus: Xen paravirtualised PCI hotplug support.
  xen/x86/PCI: Add support for the Xen PCI subsystem
  x86: Introduce x86_msi_ops
  msi: Introduce default_[teardown|setup]_msi_irqs with fallback.
  x86/PCI: Export pci_walk_bus function.
  x86/PCI: make sure _PAGE_IOMAP it set on pci mappings
  x86/PCI: Clean up pci_cache_line_size
  xen: fix shared irq device passthrough
  xen: Provide a variant of xen_poll_irq with timeout.
  xen: Find an unbound irq number in reverse order (high to low).
  xen: statically initialize cpu_evtchn_mask_p
  ...

Fix up trivial conflicts in drivers/pci/Makefile

21 files changed, 704 insertions, 33 deletions

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index e0963f52bfdd..e8327686d3c5 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1893,6 +1893,11 @@ config PCI_OLPC
 	def_bool y
 	depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
 
+config PCI_XEN
+	def_bool y
+	depends on PCI && XEN
+	select SWIOTLB_XEN
+
 config PCI_DOMAINS
 	def_bool y
 	depends on PCI
diff --git a/arch/x86/include/asm/acpi.h b/arch/x86/include/asm/acpi.h
index 92091de11113..55d106b5e31b 100644
--- a/arch/x86/include/asm/acpi.h
+++ b/arch/x86/include/asm/acpi.h
@@ -93,6 +93,9 @@ extern u8 acpi_sci_flags;
 extern int acpi_sci_override_gsi;
 void acpi_pic_sci_set_trigger(unsigned int, u16);
 
+extern int (*__acpi_register_gsi)(struct device *dev, u32 gsi,
+				  int trigger, int polarity);
+
 static inline void disable_acpi(void)
 {
 	acpi_disabled = 1;
diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h
index f0203f4791a8..072273082528 100644
--- a/arch/x86/include/asm/io.h
+++ b/arch/x86/include/asm/io.h
@@ -41,6 +41,8 @@
 #include <asm-generic/int-ll64.h>
 #include <asm/page.h>
 
+#include <xen/xen.h>
+
 #define build_mmio_read(name, size, type, reg, barrier) \
 static inline type name(const volatile void __iomem *addr) \
 { type ret; asm volatile("mov" size " %1,%0":reg (ret) \
@@ -351,6 +353,17 @@ extern void early_iounmap(void __iomem *addr, unsigned long size);
 extern void fixup_early_ioremap(void);
 extern bool is_early_ioremap_ptep(pte_t *ptep);
 
+#ifdef CONFIG_XEN
+struct bio_vec;
+
+extern bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
+				      const struct bio_vec *vec2);
+
+#define BIOVEC_PHYS_MERGEABLE(vec1, vec2)				\
+	(__BIOVEC_PHYS_MERGEABLE(vec1, vec2) &&				\
+	 (!xen_domain() || xen_biovec_phys_mergeable(vec1, vec2)))
+#endif	/* CONFIG_XEN */
+
 #define IO_SPACE_LIMIT 0xffff
 
 #endif /* _ASM_X86_IO_H */
diff --git a/arch/x86/include/asm/io_apic.h b/arch/x86/include/asm/io_apic.h
index c8be4566c3d2..a6b28d017c2f 100644
--- a/arch/x86/include/asm/io_apic.h
+++ b/arch/x86/include/asm/io_apic.h
@@ -169,6 +169,7 @@ extern void mask_IO_APIC_setup(struct IO_APIC_route_entry **ioapic_entries);
 extern int restore_IO_APIC_setup(struct IO_APIC_route_entry **ioapic_entries);
 
 extern void probe_nr_irqs_gsi(void);
+extern int get_nr_irqs_gsi(void);
 
 extern void setup_ioapic_ids_from_mpc(void);
 
diff --git a/arch/x86/include/asm/pci.h b/arch/x86/include/asm/pci.h
index d395540ff894..ca0437c714b2 100644
--- a/arch/x86/include/asm/pci.h
+++ b/arch/x86/include/asm/pci.h
@@ -7,6 +7,7 @@
 #include <linux/string.h>
 #include <asm/scatterlist.h>
 #include <asm/io.h>
+#include <asm/x86_init.h>
 
 #ifdef __KERNEL__
 
@@ -94,8 +95,36 @@ static inline void early_quirks(void) { }
 
 extern void pci_iommu_alloc(void);
 
-/* MSI arch hook */
-#define arch_setup_msi_irqs arch_setup_msi_irqs
+#ifdef CONFIG_PCI_MSI
+/* MSI arch specific hooks */
+static inline int x86_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
+{
+	return x86_msi.setup_msi_irqs(dev, nvec, type);
+}
+
+static inline void x86_teardown_msi_irqs(struct pci_dev *dev)
+{
+	x86_msi.teardown_msi_irqs(dev);
+}
+
+static inline void x86_teardown_msi_irq(unsigned int irq)
+{
+	x86_msi.teardown_msi_irq(irq);
+}
+#define arch_setup_msi_irqs x86_setup_msi_irqs
+#define arch_teardown_msi_irqs x86_teardown_msi_irqs
+#define arch_teardown_msi_irq x86_teardown_msi_irq
+/* implemented in arch/x86/kernel/apic/io_apic. */
+int native_setup_msi_irqs(struct pci_dev *dev, int nvec, int type);
+void native_teardown_msi_irq(unsigned int irq);
+/* default to the implementation in drivers/lib/msi.c */
+#define HAVE_DEFAULT_MSI_TEARDOWN_IRQS
+void default_teardown_msi_irqs(struct pci_dev *dev);
+#else
+#define native_setup_msi_irqs		NULL
+#define native_teardown_msi_irq		NULL
+#define default_teardown_msi_irqs	NULL
+#endif
 
 #define PCI_DMA_BUS_IS_PHYS (dma_ops->is_phys)
 
diff --git a/arch/x86/include/asm/pci_x86.h b/arch/x86/include/asm/pci_x86.h
index 49c7219826f9..704526734bef 100644
--- a/arch/x86/include/asm/pci_x86.h
+++ b/arch/x86/include/asm/pci_x86.h
@@ -47,6 +47,7 @@ enum pci_bf_sort_state {
 extern unsigned int pcibios_max_latency;
 
 void pcibios_resource_survey(void);
+void pcibios_set_cache_line_size(void);
 
 /* pci-pc.c */
 
diff --git a/arch/x86/include/asm/x86_init.h b/arch/x86/include/asm/x86_init.h
index baa579c8e038..64642ad019fb 100644
--- a/arch/x86/include/asm/x86_init.h
+++ b/arch/x86/include/asm/x86_init.h
@@ -154,9 +154,18 @@ struct x86_platform_ops {
 	int (*i8042_detect)(void);
 };
 
+struct pci_dev;
+
+struct x86_msi_ops {
+	int (*setup_msi_irqs)(struct pci_dev *dev, int nvec, int type);
+	void (*teardown_msi_irq)(unsigned int irq);
+	void (*teardown_msi_irqs)(struct pci_dev *dev);
+};
+
 extern struct x86_init_ops x86_init;
 extern struct x86_cpuinit_ops x86_cpuinit;
 extern struct x86_platform_ops x86_platform;
+extern struct x86_msi_ops x86_msi;
 
 extern void x86_init_noop(void);
 extern void x86_init_uint_noop(unsigned int unused);
diff --git a/arch/x86/include/asm/xen/pci.h b/arch/x86/include/asm/xen/pci.h
new file mode 100644
index 000000000000..2329b3eaf8d3
--- /dev/null
+++ b/arch/x86/include/asm/xen/pci.h
@@ -0,0 +1,65 @@
+#ifndef _ASM_X86_XEN_PCI_H
+#define _ASM_X86_XEN_PCI_H
+
+#if defined(CONFIG_PCI_XEN)
+extern int __init pci_xen_init(void);
+extern int __init pci_xen_hvm_init(void);
+#define pci_xen 1
+#else
+#define pci_xen 0
+#define pci_xen_init (0)
+static inline int pci_xen_hvm_init(void)
+{
+	return -1;
+}
+#endif
+#if defined(CONFIG_XEN_DOM0)
+void __init xen_setup_pirqs(void);
+#else
+static inline void __init xen_setup_pirqs(void)
+{
+}
+#endif
+
+#if defined(CONFIG_PCI_MSI)
+#if defined(CONFIG_PCI_XEN)
+/* The drivers/pci/xen-pcifront.c sets this structure to
+ * its own functions.
+ */
+struct xen_pci_frontend_ops {
+	int (*enable_msi)(struct pci_dev *dev, int **vectors);
+	void (*disable_msi)(struct pci_dev *dev);
+	int (*enable_msix)(struct pci_dev *dev, int **vectors, int nvec);
+	void (*disable_msix)(struct pci_dev *dev);
+};
+
+extern struct xen_pci_frontend_ops *xen_pci_frontend;
+
+static inline int xen_pci_frontend_enable_msi(struct pci_dev *dev,
+					      int **vectors)
+{
+	if (xen_pci_frontend && xen_pci_frontend->enable_msi)
+		return xen_pci_frontend->enable_msi(dev, vectors);
+	return -ENODEV;
+}
+static inline void xen_pci_frontend_disable_msi(struct pci_dev *dev)
+{
+	if (xen_pci_frontend && xen_pci_frontend->disable_msi)
+			xen_pci_frontend->disable_msi(dev);
+}
+static inline int xen_pci_frontend_enable_msix(struct pci_dev *dev,
+					       int **vectors, int nvec)
+{
+	if (xen_pci_frontend && xen_pci_frontend->enable_msix)
+		return xen_pci_frontend->enable_msix(dev, vectors, nvec);
+	return -ENODEV;
+}
+static inline void xen_pci_frontend_disable_msix(struct pci_dev *dev)
+{
+	if (xen_pci_frontend && xen_pci_frontend->disable_msix)
+			xen_pci_frontend->disable_msix(dev);
+}
+#endif /* CONFIG_PCI_XEN */
+#endif /* CONFIG_PCI_MSI */
+
+#endif	/* _ASM_X86_XEN_PCI_H */
diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index c05872aa3ce0..71232b941b6c 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -513,35 +513,62 @@ int acpi_isa_irq_to_gsi(unsigned isa_irq, u32 *gsi)
 	return 0;
 }
 
-/*
- * success: return IRQ number (>=0)
- * failure: return < 0
- */
-int acpi_register_gsi(struct device *dev, u32 gsi, int trigger, int polarity)
+static int acpi_register_gsi_pic(struct device *dev, u32 gsi,
+				 int trigger, int polarity)
 {
-	unsigned int irq;
-	unsigned int plat_gsi = gsi;
-
 #ifdef CONFIG_PCI
 	/*
 	 * Make sure all (legacy) PCI IRQs are set as level-triggered.
 	 */
-	if (acpi_irq_model == ACPI_IRQ_MODEL_PIC) {
-		if (trigger == ACPI_LEVEL_SENSITIVE)
-			eisa_set_level_irq(gsi);
-	}
+	if (trigger == ACPI_LEVEL_SENSITIVE)
+		eisa_set_level_irq(gsi);
 #endif
 
+	return gsi;
+}
+
+static int acpi_register_gsi_ioapic(struct device *dev, u32 gsi,
+				    int trigger, int polarity)
+{
 #ifdef CONFIG_X86_IO_APIC
-	if (acpi_irq_model == ACPI_IRQ_MODEL_IOAPIC) {
-		plat_gsi = mp_register_gsi(dev, gsi, trigger, polarity);
-	}
+	gsi = mp_register_gsi(dev, gsi, trigger, polarity);
 #endif
+
+	return gsi;
+}
+
+int (*__acpi_register_gsi)(struct device *dev, u32 gsi,
+			   int trigger, int polarity) = acpi_register_gsi_pic;
+
+/*
+ * success: return IRQ number (>=0)
+ * failure: return < 0
+ */
+int acpi_register_gsi(struct device *dev, u32 gsi, int trigger, int polarity)
+{
+	unsigned int irq;
+	unsigned int plat_gsi = gsi;
+
+	plat_gsi = (*__acpi_register_gsi)(dev, gsi, trigger, polarity);
 	irq = gsi_to_irq(plat_gsi);
 
 	return irq;
 }
 
+void __init acpi_set_irq_model_pic(void)
+{
+	acpi_irq_model = ACPI_IRQ_MODEL_PIC;
+	__acpi_register_gsi = acpi_register_gsi_pic;
+	acpi_ioapic = 0;
+}
+
+void __init acpi_set_irq_model_ioapic(void)
+{
+	acpi_irq_model = ACPI_IRQ_MODEL_IOAPIC;
+	__acpi_register_gsi = acpi_register_gsi_ioapic;
+	acpi_ioapic = 1;
+}
+
 /*
  *  ACPI based hotplug support for CPU
  */
@@ -1259,8 +1286,7 @@ static void __init acpi_process_madt(void)
 			 */
 			error = acpi_parse_madt_ioapic_entries();
 			if (!error) {
-				acpi_irq_model = ACPI_IRQ_MODEL_IOAPIC;
-				acpi_ioapic = 1;
+				acpi_set_irq_model_ioapic();
 
 				smp_found_config = 1;
 			}
diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 8ae808d110f4..0929191d83cf 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -3331,7 +3331,7 @@ static int setup_msi_irq(struct pci_dev *dev, struct msi_desc *msidesc, int irq)
 	return 0;
 }
 
-int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
+int native_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
 {
 	int node, ret, sub_handle, index = 0;
 	unsigned int irq, irq_want;
@@ -3389,7 +3389,7 @@ error:
 	return ret;
 }
 
-void arch_teardown_msi_irq(unsigned int irq)
+void native_teardown_msi_irq(unsigned int irq)
 {
 	destroy_irq(irq);
 }
@@ -3650,6 +3650,11 @@ void __init probe_nr_irqs_gsi(void)
 	printk(KERN_DEBUG "nr_irqs_gsi: %d\n", nr_irqs_gsi);
 }
 
+int get_nr_irqs_gsi(void)
+{
+	return nr_irqs_gsi;
+}
+
 #ifdef CONFIG_SPARSE_IRQ
 int __init arch_probe_nr_irqs(void)
 {
diff --git a/arch/x86/kernel/x86_init.c b/arch/x86/kernel/x86_init.c
index cd6da6bf3eca..ceb2911aa439 100644
--- a/arch/x86/kernel/x86_init.c
+++ b/arch/x86/kernel/x86_init.c
@@ -6,10 +6,12 @@
 #include <linux/init.h>
 #include <linux/ioport.h>
 #include <linux/module.h>
+#include <linux/pci.h>
 
 #include <asm/bios_ebda.h>
 #include <asm/paravirt.h>
 #include <asm/pci_x86.h>
+#include <asm/pci.h>
 #include <asm/mpspec.h>
 #include <asm/setup.h>
 #include <asm/apic.h>
@@ -99,3 +101,8 @@ struct x86_platform_ops x86_platform = {
 };
 
 EXPORT_SYMBOL_GPL(x86_platform);
+struct x86_msi_ops x86_msi = {
+	.setup_msi_irqs = native_setup_msi_irqs,
+	.teardown_msi_irq = native_teardown_msi_irq,
+	.teardown_msi_irqs = default_teardown_msi_irqs,
+};
diff --git a/arch/x86/pci/Makefile b/arch/x86/pci/Makefile
index a0207a7fdf39..effd96e33f16 100644
--- a/arch/x86/pci/Makefile
+++ b/arch/x86/pci/Makefile
@@ -4,6 +4,7 @@ obj-$(CONFIG_PCI_BIOS)		+= pcbios.o
 obj-$(CONFIG_PCI_MMCONFIG)	+= mmconfig_$(BITS).o direct.o mmconfig-shared.o
 obj-$(CONFIG_PCI_DIRECT)	+= direct.o
 obj-$(CONFIG_PCI_OLPC)		+= olpc.o
+obj-$(CONFIG_PCI_XEN)		+= xen.o
 
 obj-y				+= fixup.o
 obj-$(CONFIG_ACPI)		+= acpi.o
diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
index a0772af64efb..f7c8a399978c 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -421,16 +421,10 @@ struct pci_bus * __devinit pcibios_scan_root(int busnum)
 
 	return bus;
 }
-
-int __init pcibios_init(void)
+void __init pcibios_set_cache_line_size(void)
 {
 	struct cpuinfo_x86 *c = &boot_cpu_data;
 
-	if (!raw_pci_ops) {
-		printk(KERN_WARNING "PCI: System does not support PCI\n");
-		return 0;
-	}
-
 	/*
 	 * Set PCI cacheline size to that of the CPU if the CPU has reported it.
 	 * (For older CPUs that don't support cpuid, we se it to 32 bytes
@@ -445,7 +439,16 @@ int __init pcibios_init(void)
  		pci_dfl_cache_line_size = 32 >> 2;
 		printk(KERN_DEBUG "PCI: Unknown cacheline size. Setting to 32 bytes\n");
 	}
+}
+
+int __init pcibios_init(void)
+{
+	if (!raw_pci_ops) {
+		printk(KERN_WARNING "PCI: System does not support PCI\n");
+		return 0;
+	}
 
+	pcibios_set_cache_line_size();
 	pcibios_resource_survey();
 
 	if (pci_bf_sort >= pci_force_bf)
diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c
index 826140af3c3c..c4bb261c106e 100644
--- a/arch/x86/pci/i386.c
+++ b/arch/x86/pci/i386.c
@@ -316,6 +316,8 @@ int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
 		 */
 		prot |= _PAGE_CACHE_UC_MINUS;
 
+	prot |= _PAGE_IOMAP;	/* creating a mapping for IO */
+
 	vma->vm_page_prot = __pgprot(prot);
 
 	if (io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
new file mode 100644
index 000000000000..117f5b8daf75
--- /dev/null
+++ b/arch/x86/pci/xen.c
@@ -0,0 +1,414 @@
+/*
+ * Xen PCI Frontend Stub - puts some "dummy" functions in to the Linux
+ *			   x86 PCI core to support the Xen PCI Frontend
+ *
+ *   Author: Ryan Wilson <hap9@epoch.ncsc.mil>
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <linux/acpi.h>
+
+#include <linux/io.h>
+#include <asm/io_apic.h>
+#include <asm/pci_x86.h>
+
+#include <asm/xen/hypervisor.h>
+
+#include <xen/features.h>
+#include <xen/events.h>
+#include <asm/xen/pci.h>
+
+#ifdef CONFIG_ACPI
+static int xen_hvm_register_pirq(u32 gsi, int triggering)
+{
+	int rc, irq;
+	struct physdev_map_pirq map_irq;
+	int shareable = 0;
+	char *name;
+
+	if (!xen_hvm_domain())
+		return -1;
+
+	map_irq.domid = DOMID_SELF;
+	map_irq.type = MAP_PIRQ_TYPE_GSI;
+	map_irq.index = gsi;
+	map_irq.pirq = -1;
+
+	rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
+	if (rc) {
+		printk(KERN_WARNING "xen map irq failed %d\n", rc);
+		return -1;
+	}
+
+	if (triggering == ACPI_EDGE_SENSITIVE) {
+		shareable = 0;
+		name = "ioapic-edge";
+	} else {
+		shareable = 1;
+		name = "ioapic-level";
+	}
+
+	irq = xen_map_pirq_gsi(map_irq.pirq, gsi, shareable, name);
+
+	printk(KERN_DEBUG "xen: --> irq=%d, pirq=%d\n", irq, map_irq.pirq);
+
+	return irq;
+}
+
+static int acpi_register_gsi_xen_hvm(struct device *dev, u32 gsi,
+				 int trigger, int polarity)
+{
+	return xen_hvm_register_pirq(gsi, trigger);
+}
+#endif
+
+#if defined(CONFIG_PCI_MSI)
+#include <linux/msi.h>
+#include <asm/msidef.h>
+
+struct xen_pci_frontend_ops *xen_pci_frontend;
+EXPORT_SYMBOL_GPL(xen_pci_frontend);
+
+static void xen_msi_compose_msg(struct pci_dev *pdev, unsigned int pirq,
+		struct msi_msg *msg)
+{
+	/* We set vector == 0 to tell the hypervisor we don't care about it,
+	 * but we want a pirq setup instead.
+	 * We use the dest_id field to pass the pirq that we want. */
+	msg->address_hi = MSI_ADDR_BASE_HI | MSI_ADDR_EXT_DEST_ID(pirq);
+	msg->address_lo =
+		MSI_ADDR_BASE_LO |
+		MSI_ADDR_DEST_MODE_PHYSICAL |
+		MSI_ADDR_REDIRECTION_CPU |
+		MSI_ADDR_DEST_ID(pirq);
+
+	msg->data =
+		MSI_DATA_TRIGGER_EDGE |
+		MSI_DATA_LEVEL_ASSERT |
+		/* delivery mode reserved */
+		(3 << 8) |
+		MSI_DATA_VECTOR(0);
+}
+
+static int xen_hvm_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
+{
+	int irq, pirq, ret = 0;
+	struct msi_desc *msidesc;
+	struct msi_msg msg;
+
+	list_for_each_entry(msidesc, &dev->msi_list, list) {
+		xen_allocate_pirq_msi((type == PCI_CAP_ID_MSIX) ?
+				"msi-x" : "msi", &irq, &pirq);
+		if (irq < 0 || pirq < 0)
+			goto error;
+		printk(KERN_DEBUG "xen: msi --> irq=%d, pirq=%d\n", irq, pirq);
+		xen_msi_compose_msg(dev, pirq, &msg);
+		ret = set_irq_msi(irq, msidesc);
+		if (ret < 0)
+			goto error_while;
+		write_msi_msg(irq, &msg);
+	}
+	return 0;
+
+error_while:
+	unbind_from_irqhandler(irq, NULL);
+error:
+	if (ret == -ENODEV)
+		dev_err(&dev->dev, "Xen PCI frontend has not registered" \
+				" MSI/MSI-X support!\n");
+
+	return ret;
+}
+
+/*
+ * For MSI interrupts we have to use drivers/xen/event.s functions to
+ * allocate an irq_desc and setup the right */
+
+
+static int xen_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
+{
+	int irq, ret, i;
+	struct msi_desc *msidesc;
+	int *v;
+
+	v = kzalloc(sizeof(int) * max(1, nvec), GFP_KERNEL);
+	if (!v)
+		return -ENOMEM;
+
+	if (type == PCI_CAP_ID_MSIX)
+		ret = xen_pci_frontend_enable_msix(dev, &v, nvec);
+	else
+		ret = xen_pci_frontend_enable_msi(dev, &v);
+	if (ret)
+		goto error;
+	i = 0;
+	list_for_each_entry(msidesc, &dev->msi_list, list) {
+		irq = xen_allocate_pirq(v[i], 0, /* not sharable */
+			(type == PCI_CAP_ID_MSIX) ?
+			"pcifront-msi-x" : "pcifront-msi");
+		if (irq < 0)
+			return -1;
+
+		ret = set_irq_msi(irq, msidesc);
+		if (ret)
+			goto error_while;
+		i++;
+	}
+	kfree(v);
+	return 0;
+
+error_while:
+	unbind_from_irqhandler(irq, NULL);
+error:
+	if (ret == -ENODEV)
+		dev_err(&dev->dev, "Xen PCI frontend has not registered" \
+			" MSI/MSI-X support!\n");
+
+	kfree(v);
+	return ret;
+}
+
+static void xen_teardown_msi_irqs(struct pci_dev *dev)
+{
+	struct msi_desc *msidesc;
+
+	msidesc = list_entry(dev->msi_list.next, struct msi_desc, list);
+	if (msidesc->msi_attrib.is_msix)
+		xen_pci_frontend_disable_msix(dev);
+	else
+		xen_pci_frontend_disable_msi(dev);
+}
+
+static void xen_teardown_msi_irq(unsigned int irq)
+{
+	xen_destroy_irq(irq);
+}
+
+static int xen_initdom_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
+{
+	int irq, ret;
+	struct msi_desc *msidesc;
+
+	list_for_each_entry(msidesc, &dev->msi_list, list) {
+		irq = xen_create_msi_irq(dev, msidesc, type);
+		if (irq < 0)
+			return -1;
+
+		ret = set_irq_msi(irq, msidesc);
+		if (ret)
+			goto error;
+	}
+	return 0;
+
+error:
+	xen_destroy_irq(irq);
+	return ret;
+}
+#endif
+
+static int xen_pcifront_enable_irq(struct pci_dev *dev)
+{
+	int rc;
+	int share = 1;
+
+	dev_info(&dev->dev, "Xen PCI enabling IRQ: %d\n", dev->irq);
+
+	if (dev->irq < 0)
+		return -EINVAL;
+
+	if (dev->irq < NR_IRQS_LEGACY)
+		share = 0;
+
+	rc = xen_allocate_pirq(dev->irq, share, "pcifront");
+	if (rc < 0) {
+		dev_warn(&dev->dev, "Xen PCI IRQ: %d, failed to register:%d\n",
+			 dev->irq, rc);
+		return rc;
+	}
+	return 0;
+}
+
+int __init pci_xen_init(void)
+{
+	if (!xen_pv_domain() || xen_initial_domain())
+		return -ENODEV;
+
+	printk(KERN_INFO "PCI: setting up Xen PCI frontend stub\n");
+
+	pcibios_set_cache_line_size();
+
+	pcibios_enable_irq = xen_pcifront_enable_irq;
+	pcibios_disable_irq = NULL;
+
+#ifdef CONFIG_ACPI
+	/* Keep ACPI out of the picture */
+	acpi_noirq = 1;
+#endif
+
+#ifdef CONFIG_PCI_MSI
+	x86_msi.setup_msi_irqs = xen_setup_msi_irqs;
+	x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
+	x86_msi.teardown_msi_irqs = xen_teardown_msi_irqs;
+#endif
+	return 0;
+}
+
+int __init pci_xen_hvm_init(void)
+{
+	if (!xen_feature(XENFEAT_hvm_pirqs))
+		return 0;
+
+#ifdef CONFIG_ACPI
+	/*
+	 * We don't want to change the actual ACPI delivery model,
+	 * just how GSIs get registered.
+	 */
+	__acpi_register_gsi = acpi_register_gsi_xen_hvm;
+#endif
+
+#ifdef CONFIG_PCI_MSI
+	x86_msi.setup_msi_irqs = xen_hvm_setup_msi_irqs;
+	x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
+#endif
+	return 0;
+}
+
+#ifdef CONFIG_XEN_DOM0
+static int xen_register_pirq(u32 gsi, int triggering)
+{
+	int rc, irq;
+	struct physdev_map_pirq map_irq;
+	int shareable = 0;
+	char *name;
+
+	if (!xen_pv_domain())
+		return -1;
+
+	if (triggering == ACPI_EDGE_SENSITIVE) {
+		shareable = 0;
+		name = "ioapic-edge";
+	} else {
+		shareable = 1;
+		name = "ioapic-level";
+	}
+
+	irq = xen_allocate_pirq(gsi, shareable, name);
+
+	printk(KERN_DEBUG "xen: --> irq=%d\n", irq);
+
+	if (irq < 0)
+		goto out;
+
+	map_irq.domid = DOMID_SELF;
+	map_irq.type = MAP_PIRQ_TYPE_GSI;
+	map_irq.index = gsi;
+	map_irq.pirq = irq;
+
+	rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
+	if (rc) {
+		printk(KERN_WARNING "xen map irq failed %d\n", rc);
+		return -1;
+	}
+
+out:
+	return irq;
+}
+
+static int xen_register_gsi(u32 gsi, int triggering, int polarity)
+{
+	int rc, irq;
+	struct physdev_setup_gsi setup_gsi;
+
+	if (!xen_pv_domain())
+		return -1;
+
+	printk(KERN_DEBUG "xen: registering gsi %u triggering %d polarity %d\n",
+			gsi, triggering, polarity);
+
+	irq = xen_register_pirq(gsi, triggering);
+
+	setup_gsi.gsi = gsi;
+	setup_gsi.triggering = (triggering == ACPI_EDGE_SENSITIVE ? 0 : 1);
+	setup_gsi.polarity = (polarity == ACPI_ACTIVE_HIGH ? 0 : 1);
+
+	rc = HYPERVISOR_physdev_op(PHYSDEVOP_setup_gsi, &setup_gsi);
+	if (rc == -EEXIST)
+		printk(KERN_INFO "Already setup the GSI :%d\n", gsi);
+	else if (rc) {
+		printk(KERN_ERR "Failed to setup GSI :%d, err_code:%d\n",
+				gsi, rc);
+	}
+
+	return irq;
+}
+
+static __init void xen_setup_acpi_sci(void)
+{
+	int rc;
+	int trigger, polarity;
+	int gsi = acpi_sci_override_gsi;
+
+	if (!gsi)
+		return;
+
+	rc = acpi_get_override_irq(gsi, &trigger, &polarity);
+	if (rc) {
+		printk(KERN_WARNING "xen: acpi_get_override_irq failed for acpi"
+				" sci, rc=%d\n", rc);
+		return;
+	}
+	trigger = trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE;
+	polarity = polarity ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH;
+	
+	printk(KERN_INFO "xen: sci override: global_irq=%d trigger=%d "
+			"polarity=%d\n", gsi, trigger, polarity);
+
+	gsi = xen_register_gsi(gsi, trigger, polarity);
+	printk(KERN_INFO "xen: acpi sci %d\n", gsi);
+
+	return;
+}
+
+static int acpi_register_gsi_xen(struct device *dev, u32 gsi,
+				 int trigger, int polarity)
+{
+	return xen_register_gsi(gsi, trigger, polarity);
+}
+
+static int __init pci_xen_initial_domain(void)
+{
+#ifdef CONFIG_PCI_MSI
+	x86_msi.setup_msi_irqs = xen_initdom_setup_msi_irqs;
+	x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
+#endif
+	xen_setup_acpi_sci();
+	__acpi_register_gsi = acpi_register_gsi_xen;
+
+	return 0;
+}
+
+void __init xen_setup_pirqs(void)
+{
+	int irq;
+
+	pci_xen_initial_domain();
+
+	if (0 == nr_ioapics) {
+		for (irq = 0; irq < NR_IRQS_LEGACY; irq++)
+			xen_allocate_pirq(irq, 0, "xt-pic");
+		return;
+	}
+
+	/* Pre-allocate legacy irqs */
+	for (irq = 0; irq < NR_IRQS_LEGACY; irq++) {
+		int trigger, polarity;
+
+		if (acpi_get_override_irq(irq, &trigger, &polarity) == -1)
+			continue;
+
+		xen_register_pirq(irq,
+			trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE);
+	}
+}
+#endif
diff --git a/arch/x86/xen/Kconfig b/arch/x86/xen/Kconfig
index 90a7f5ad6916..5b54892e4bc3 100644
--- a/arch/x86/xen/Kconfig
+++ b/arch/x86/xen/Kconfig
@@ -13,6 +13,16 @@ config XEN
 	  kernel to boot in a paravirtualized environment under the
 	  Xen hypervisor.
 
+config XEN_DOM0
+	def_bool y
+	depends on XEN && PCI_XEN && SWIOTLB_XEN
+	depends on X86_LOCAL_APIC && X86_IO_APIC && ACPI && PCI
+
+# Dummy symbol since people have come to rely on the PRIVILEGED_GUEST
+# name in tools.
+config XEN_PRIVILEGED_GUEST
+	def_bool XEN_DOM0
+
 config XEN_PVHVM
 	def_bool y
 	depends on XEN
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 70ddeaeb1ef3..235c0f4d3861 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -46,6 +46,7 @@
 #include <asm/paravirt.h>
 #include <asm/apic.h>
 #include <asm/page.h>
+#include <asm/xen/pci.h>
 #include <asm/xen/hypercall.h>
 #include <asm/xen/hypervisor.h>
 #include <asm/fixmap.h>
@@ -236,6 +237,7 @@ static __init void xen_init_cpuid_mask(void)
 	cpuid_leaf1_edx_mask =
 		~((1 << X86_FEATURE_MCE)  |  /* disable MCE */
 		  (1 << X86_FEATURE_MCA)  |  /* disable MCA */
+		  (1 << X86_FEATURE_MTRR) |  /* disable MTRR */
 		  (1 << X86_FEATURE_ACC));   /* thermal monitoring */
 
 	if (!xen_initial_domain())
@@ -1184,6 +1186,7 @@ asmlinkage void __init xen_start_kernel(void)
 
 	xen_raw_console_write("mapping kernel into physical memory\n");
 	pgd = xen_setup_kernel_pagetable(pgd, xen_start_info->nr_pages);
+	xen_ident_map_ISA();
 
 	/* Allocate and initialize top and mid mfn levels for p2m structure */
 	xen_build_mfn_list_list();
@@ -1222,6 +1225,8 @@ asmlinkage void __init xen_start_kernel(void)
 		add_preferred_console("xenboot", 0, NULL);
 		add_preferred_console("tty", 0, NULL);
 		add_preferred_console("hvc", 0, NULL);
+		if (pci_xen)
+			x86_init.pci.arch_init = pci_xen_init;
 	} else {
 		/* Make sure ACS will be enabled */
 		pci_request_acs();
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index 9631c90907eb..c237b810b03f 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -1975,6 +1975,7 @@ static void *m2v(phys_addr_t maddr)
 	return __ka(m2p(maddr));
 }
 
+/* Set the page permissions on an identity-mapped pages */
 static void set_page_prot(void *addr, pgprot_t prot)
 {
 	unsigned long pfn = __pa(addr) >> PAGE_SHIFT;
@@ -2159,6 +2160,8 @@ __init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd,
 }
 #endif	/* CONFIG_X86_64 */
 
+static unsigned char dummy_mapping[PAGE_SIZE] __page_aligned_bss;
+
 static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot)
 {
 	pte_t pte;
@@ -2179,15 +2182,28 @@ static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot)
 #else
 	case VSYSCALL_LAST_PAGE ... VSYSCALL_FIRST_PAGE:
 #endif
-#ifdef CONFIG_X86_LOCAL_APIC
-	case FIX_APIC_BASE:	/* maps dummy local APIC */
-#endif
 	case FIX_TEXT_POKE0:
 	case FIX_TEXT_POKE1:
 		/* All local page mappings */
 		pte = pfn_pte(phys, prot);
 		break;
 
+#ifdef CONFIG_X86_LOCAL_APIC
+	case FIX_APIC_BASE:	/* maps dummy local APIC */
+		pte = pfn_pte(PFN_DOWN(__pa(dummy_mapping)), PAGE_KERNEL);
+		break;
+#endif
+
+#ifdef CONFIG_X86_IO_APIC
+	case FIX_IO_APIC_BASE_0 ... FIX_IO_APIC_BASE_END:
+		/*
+		 * We just don't map the IO APIC - all access is via
+		 * hypercalls.  Keep the address in the pte for reference.
+		 */
+		pte = pfn_pte(PFN_DOWN(__pa(dummy_mapping)), PAGE_KERNEL);
+		break;
+#endif
+
 	case FIX_PARAVIRT_BOOTMAP:
 		/* This is an MFN, but it isn't an IO mapping from the
 		   IO domain */
@@ -2212,6 +2228,29 @@ static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot)
 #endif
 }
 
+__init void xen_ident_map_ISA(void)
+{
+	unsigned long pa;
+
+	/*
+	 * If we're dom0, then linear map the ISA machine addresses into
+	 * the kernel's address space.
+	 */
+	if (!xen_initial_domain())
+		return;
+
+	xen_raw_printk("Xen: setup ISA identity maps\n");
+
+	for (pa = ISA_START_ADDRESS; pa < ISA_END_ADDRESS; pa += PAGE_SIZE) {
+		pte_t pte = mfn_pte(PFN_DOWN(pa), PAGE_KERNEL_IO);
+
+		if (HYPERVISOR_update_va_mapping(PAGE_OFFSET + pa, pte, 0))
+			BUG();
+	}
+
+	xen_flush_tlb();
+}
+
 static __init void xen_post_allocator_init(void)
 {
 	pv_mmu_ops.set_pte = xen_set_pte;
@@ -2320,6 +2359,8 @@ void __init xen_init_mmu_ops(void)
 	pv_mmu_ops = xen_mmu_ops;
 
 	vmap_lazy_unmap = false;
+
+	memset(dummy_mapping, 0xff, PAGE_SIZE);
 }
 
 /* Protected by xen_reservation_lock. */
diff --git a/arch/x86/xen/pci-swiotlb-xen.c b/arch/x86/xen/pci-swiotlb-xen.c
index 22471001b74c..bfd0632fe65e 100644
--- a/arch/x86/xen/pci-swiotlb-xen.c
+++ b/arch/x86/xen/pci-swiotlb-xen.c
@@ -1,6 +1,7 @@
 /* Glue code to lib/swiotlb-xen.c */
 
 #include <linux/dma-mapping.h>
+#include <linux/pci.h>
 #include <xen/swiotlb-xen.h>
 
 #include <asm/xen/hypervisor.h>
@@ -55,6 +56,9 @@ void __init pci_xen_swiotlb_init(void)
 	if (xen_swiotlb) {
 		xen_swiotlb_init(1);
 		dma_ops = &xen_swiotlb_dma_ops;
+
+		/* Make sure ACS will be enabled */
+		pci_request_acs();
 	}
 }
 IOMMU_INIT_FINISH(pci_xen_swiotlb_detect,
diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index 105db2501050..b1dbdaa23ecc 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -204,6 +204,9 @@ char * __init xen_memory_setup(void)
 	 * Even though this is normal, usable memory under Xen, reserve
 	 * ISA memory anyway because too many things think they can poke
 	 * about in there.
+	 *
+	 * In a dom0 kernel, this region is identity mapped with the
+	 * hardware ISA area, so it really is out of bounds.
 	 */
 	e820_add_region(ISA_START_ADDRESS, ISA_END_ADDRESS - ISA_START_ADDRESS,
 			E820_RESERVED);
@@ -367,7 +370,5 @@ void __init xen_arch_setup(void)
 
 	pm_idle = xen_idle;
 
-	paravirt_disable_iospace();
-
 	fiddle_vdso();
 }
diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c
index f4d010031465..72a4c7959045 100644
--- a/arch/x86/xen/smp.c
+++ b/arch/x86/xen/smp.c
@@ -28,6 +28,7 @@
 #include <asm/xen/interface.h>
 #include <asm/xen/hypercall.h>
 
+#include <xen/xen.h>
 #include <xen/page.h>
 #include <xen/events.h>
 
@@ -156,11 +157,35 @@ static void __init xen_fill_possible_map(void)
 {
 	int i, rc;
 
+	if (xen_initial_domain())
+		return;
+
+	for (i = 0; i < nr_cpu_ids; i++) {
+		rc = HYPERVISOR_vcpu_op(VCPUOP_is_up, i, NULL);
+		if (rc >= 0) {
+			num_processors++;
+			set_cpu_possible(i, true);
+		}
+	}
+}
+
+static void __init xen_filter_cpu_maps(void)
+{
+	int i, rc;
+
+	if (!xen_initial_domain())
+		return;
+
+	num_processors = 0;
+	disabled_cpus = 0;
 	for (i = 0; i < nr_cpu_ids; i++) {
 		rc = HYPERVISOR_vcpu_op(VCPUOP_is_up, i, NULL);
 		if (rc >= 0) {
 			num_processors++;
 			set_cpu_possible(i, true);
+		} else {
+			set_cpu_possible(i, false);
+			set_cpu_present(i, false);
 		}
 	}
 }
@@ -174,6 +199,7 @@ static void __init xen_smp_prepare_boot_cpu(void)
 	   old memory can be recycled */
 	make_lowmem_page_readwrite(xen_initial_gdt);
 
+	xen_filter_cpu_maps();
 	xen_setup_vcpu_info_placement();
 }