Merge remote-tracking branch 'agraf/xen-next' into staging

30 files changed, 2343 insertions, 613 deletions

diff --git a/Makefile.target b/Makefile.target
index 21f864afd2..2e281a4588 100644
--- a/Makefile.target
+++ b/Makefile.target
@@ -206,7 +206,19 @@ QEMU_CFLAGS += $(VNC_JPEG_CFLAGS)
 QEMU_CFLAGS += $(VNC_PNG_CFLAGS)
 
 # xen backend driver support
-obj-$(CONFIG_XEN) += xen_machine_pv.o xen_domainbuild.o
+obj-i386-$(CONFIG_XEN) += xen_machine_pv.o xen_domainbuild.o
+
+ifeq ($(TARGET_BASE_ARCH), i386)
+  CONFIG_NO_XEN = $(if $(subst n,,$(CONFIG_XEN)),n,y)
+else
+  CONFIG_NO_XEN = y
+endif
+# xen support
+CONFIG_NO_XEN_MAPCACHE = $(if $(subst n,,$(CONFIG_XEN_MAPCACHE)),n,y)
+obj-i386-$(CONFIG_XEN) += xen-all.o
+obj-$(CONFIG_NO_XEN) += xen-stub.o
+obj-i386-$(CONFIG_XEN_MAPCACHE) += xen-mapcache.o
+obj-$(CONFIG_NO_XEN_MAPCACHE) += xen-mapcache-stub.o
 
 # Inter-VM PCI shared memory
 CONFIG_IVSHMEM =
diff --git a/arch_init.c b/arch_init.c
index 0c09f9118e..484b39d4dd 100644
--- a/arch_init.c
+++ b/arch_init.c
@@ -709,6 +709,11 @@ int audio_available(void)
 #endif
 }
 
+int tcg_available(void)
+{
+    return 1;
+}
+
 int kvm_available(void)
 {
 #ifdef CONFIG_KVM
diff --git a/arch_init.h b/arch_init.h
index 86ebc149bc..2de9f0852d 100644
--- a/arch_init.h
+++ b/arch_init.h
@@ -27,6 +27,7 @@ void do_smbios_option(const char *optarg);
 void cpudef_init(void);
 int audio_available(void);
 void audio_init(qemu_irq *isa_pic, PCIBus *pci_bus);
+int tcg_available(void);
 int kvm_available(void);
 int xen_available(void);
 
diff --git a/configure b/configure
index 6f75e2eb9f..3ba64015cd 100755
--- a/configure
+++ b/configure
@@ -127,6 +127,7 @@ vnc_jpeg=""
 vnc_png=""
 vnc_thread="no"
 xen=""
+xen_ctrl_version=""
 linux_aio=""
 attr=""
 vhost_net=""
@@ -1180,20 +1181,81 @@ fi
 
 if test "$xen" != "no" ; then
   xen_libs="-lxenstore -lxenctrl -lxenguest"
+
+  # Xen unstable
   cat > $TMPC <<EOF
 #include <xenctrl.h>
 #include <xs.h>
-int main(void) { xs_daemon_open(); xc_interface_open(); return 0; }
+#include <stdint.h>
+#include <xen/hvm/hvm_info_table.h>
+#if !defined(HVM_MAX_VCPUS)
+# error HVM_MAX_VCPUS not defined
+#endif
+int main(void) {
+  xc_interface *xc;
+  xs_daemon_open();
+  xc = xc_interface_open(0, 0, 0);
+  xc_hvm_set_mem_type(0, 0, HVMMEM_ram_ro, 0, 0);
+  xc_gnttab_open(NULL, 0);
+  return 0;
+}
 EOF
   if compile_prog "" "$xen_libs" ; then
+    xen_ctrl_version=410
     xen=yes
-    libs_softmmu="$xen_libs $libs_softmmu"
+
+  # Xen 4.0.0
+  elif (
+      cat > $TMPC <<EOF
+#include <xenctrl.h>
+#include <xs.h>
+#include <stdint.h>
+#include <xen/hvm/hvm_info_table.h>
+#if !defined(HVM_MAX_VCPUS)
+# error HVM_MAX_VCPUS not defined
+#endif
+int main(void) {
+  xs_daemon_open();
+  xc_interface_open();
+  xc_gnttab_open();
+  xc_hvm_set_mem_type(0, 0, HVMMEM_ram_ro, 0, 0);
+  return 0;
+}
+EOF
+      compile_prog "" "$xen_libs"
+    ) ; then
+    xen_ctrl_version=400
+    xen=yes
+
+  # Xen 3.3.0, 3.4.0
+  elif (
+      cat > $TMPC <<EOF
+#include <xenctrl.h>
+#include <xs.h>
+int main(void) {
+  xs_daemon_open();
+  xc_interface_open();
+  xc_gnttab_open();
+  xc_hvm_set_mem_type(0, 0, HVMMEM_ram_ro, 0, 0);
+  return 0;
+}
+EOF
+      compile_prog "" "$xen_libs"
+    ) ; then
+    xen_ctrl_version=330
+    xen=yes
+
+  # Xen not found or unsupported
   else
     if test "$xen" = "yes" ; then
       feature_not_found "xen"
     fi
     xen=no
   fi
+
+  if test "$xen" = yes; then
+    libs_softmmu="$xen_libs $libs_softmmu"
+  fi
 fi
 
 ##########################################
@@ -2855,6 +2917,7 @@ if test "$bluez" = "yes" ; then
 fi
 if test "$xen" = "yes" ; then
   echo "CONFIG_XEN=y" >> $config_host_mak
+  echo "CONFIG_XEN_CTRL_INTERFACE_VERSION=$xen_ctrl_version" >> $config_host_mak
 fi
 if test "$io_thread" = "yes" ; then
   echo "CONFIG_IOTHREAD=y" >> $config_host_mak
@@ -3235,7 +3298,11 @@ echo "TARGET_ABI_DIR=$TARGET_ABI_DIR" >> $config_target_mak
 case "$target_arch2" in
   i386|x86_64)
     if test "$xen" = "yes" -a "$target_softmmu" = "yes" ; then
+      target_phys_bits=64
       echo "CONFIG_XEN=y" >> $config_target_mak
+      if test "$cpu" = "i386" -o "$cpu" = "x86_64"; then
+          echo "CONFIG_XEN_MAPCACHE=y" >> $config_target_mak
+      fi
     fi
 esac
 case "$target_arch2" in
diff --git a/cpu-common.h b/cpu-common.h
index 6410cccda5..151c32c1f2 100644
--- a/cpu-common.h
+++ b/cpu-common.h
@@ -67,6 +67,7 @@ void *qemu_get_ram_ptr(ram_addr_t addr);
 /* Same but slower, to use for migration, where the order of
  * RAMBlocks must not change. */
 void *qemu_safe_ram_ptr(ram_addr_t addr);
+void qemu_put_ram_ptr(void *addr);
 /* This should not be used by devices.  */
 int qemu_ram_addr_from_host(void *ptr, ram_addr_t *ram_addr);
 ram_addr_t qemu_ram_addr_from_host_nofail(void *ptr);
diff --git a/exec.c b/exec.c
index 308a86dcc0..a6df2d6139 100644
--- a/exec.c
+++ b/exec.c
@@ -32,6 +32,7 @@
 #include "hw/qdev.h"
 #include "osdep.h"
 #include "kvm.h"
+#include "hw/xen.h"
 #include "qemu-timer.h"
 #if defined(CONFIG_USER_ONLY)
 #include <qemu.h>
@@ -51,6 +52,8 @@
 #include <libutil.h>
 #endif
 #endif
+#else /* !CONFIG_USER_ONLY */
+#include "xen-mapcache.h"
 #endif
 
 //#define DEBUG_TB_INVALIDATE
@@ -2889,6 +2892,7 @@ ram_addr_t qemu_ram_alloc_from_ptr(DeviceState *dev, const char *name,
         }
     }
 
+    new_block->offset = find_ram_offset(size);
     if (host) {
         new_block->host = host;
         new_block->flags |= RAM_PREALLOC_MASK;
@@ -2911,13 +2915,15 @@ ram_addr_t qemu_ram_alloc_from_ptr(DeviceState *dev, const char *name,
                                    PROT_EXEC|PROT_READ|PROT_WRITE,
                                    MAP_SHARED | MAP_ANONYMOUS, -1, 0);
 #else
-            new_block->host = qemu_vmalloc(size);
+            if (xen_mapcache_enabled()) {
+                xen_ram_alloc(new_block->offset, size);
+            } else {
+                new_block->host = qemu_vmalloc(size);
+            }
 #endif
             qemu_madvise(new_block->host, size, QEMU_MADV_MERGEABLE);
         }
     }
-
-    new_block->offset = find_ram_offset(size);
     new_block->length = size;
 
     QLIST_INSERT_HEAD(&ram_list.blocks, new_block, next);
@@ -2962,7 +2968,11 @@ void qemu_ram_free(ram_addr_t addr)
 #if defined(TARGET_S390X) && defined(CONFIG_KVM)
                 munmap(block->host, block->length);
 #else
-                qemu_vfree(block->host);
+                if (xen_mapcache_enabled()) {
+                    qemu_invalidate_entry(block->host);
+                } else {
+                    qemu_vfree(block->host);
+                }
 #endif
             }
             qemu_free(block);
@@ -3051,6 +3061,16 @@ void *qemu_get_ram_ptr(ram_addr_t addr)
                 QLIST_REMOVE(block, next);
                 QLIST_INSERT_HEAD(&ram_list.blocks, block, next);
             }
+            if (xen_mapcache_enabled()) {
+                /* We need to check if the requested address is in the RAM
+                 * because we don't want to map the entire memory in QEMU.
+                 */
+                if (block->offset == 0) {
+                    return qemu_map_cache(addr, 0, 1);
+                } else if (block->host == NULL) {
+                    block->host = xen_map_block(block->offset, block->length);
+                }
+            }
             return block->host + (addr - block->offset);
         }
     }
@@ -3070,6 +3090,16 @@ void *qemu_safe_ram_ptr(ram_addr_t addr)
 
     QLIST_FOREACH(block, &ram_list.blocks, next) {
         if (addr - block->offset < block->length) {
+            if (xen_mapcache_enabled()) {
+                /* We need to check if the requested address is in the RAM
+                 * because we don't want to map the entire memory in QEMU.
+                 */
+                if (block->offset == 0) {
+                    return qemu_map_cache(addr, 0, 1);
+                } else if (block->host == NULL) {
+                    block->host = xen_map_block(block->offset, block->length);
+                }
+            }
             return block->host + (addr - block->offset);
         }
     }
@@ -3080,17 +3110,48 @@ void *qemu_safe_ram_ptr(ram_addr_t addr)
     return NULL;
 }
 
+void qemu_put_ram_ptr(void *addr)
+{
+    trace_qemu_put_ram_ptr(addr);
+
+    if (xen_mapcache_enabled()) {
+        RAMBlock *block;
+
+        QLIST_FOREACH(block, &ram_list.blocks, next) {
+            if (addr == block->host) {
+                break;
+            }
+        }
+        if (block && block->host) {
+            xen_unmap_block(block->host, block->length);
+            block->host = NULL;
+        } else {
+            qemu_map_cache_unlock(addr);
+        }
+    }
+}
+
 int qemu_ram_addr_from_host(void *ptr, ram_addr_t *ram_addr)
 {
     RAMBlock *block;
     uint8_t *host = ptr;
 
     QLIST_FOREACH(block, &ram_list.blocks, next) {
+        /* This case append when the block is not mapped. */
+        if (block->host == NULL) {
+            continue;
+        }
         if (host - block->host < block->length) {
             *ram_addr = block->offset + (host - block->host);
             return 0;
         }
     }
+
+    if (xen_mapcache_enabled()) {
+        *ram_addr = qemu_ram_addr_from_mapcache(ptr);
+        return 0;
+    }
+
     return -1;
 }
 
@@ -3785,6 +3846,7 @@ void cpu_physical_memory_rw(target_phys_addr_t addr, uint8_t *buf,
                     cpu_physical_memory_set_dirty_flags(
                         addr1, (0xff & ~CODE_DIRTY_FLAG));
                 }
+                qemu_put_ram_ptr(ptr);
             }
         } else {
             if ((pd & ~TARGET_PAGE_MASK) > IO_MEM_ROM &&
@@ -3812,9 +3874,9 @@ void cpu_physical_memory_rw(target_phys_addr_t addr, uint8_t *buf,
                 }
             } else {
                 /* RAM case */
-                ptr = qemu_get_ram_ptr(pd & TARGET_PAGE_MASK) +
-                    (addr & ~TARGET_PAGE_MASK);
-                memcpy(buf, ptr, l);
+                ptr = qemu_get_ram_ptr(pd & TARGET_PAGE_MASK);
+                memcpy(buf, ptr + (addr & ~TARGET_PAGE_MASK), l);
+                qemu_put_ram_ptr(ptr);
             }
         }
         len -= l;
@@ -3855,6 +3917,7 @@ void cpu_physical_memory_write_rom(target_phys_addr_t addr,
             /* ROM/RAM case */
             ptr = qemu_get_ram_ptr(addr1);
             memcpy(ptr, buf, l);
+            qemu_put_ram_ptr(ptr);
         }
         len -= l;
         buf += l;
@@ -3996,6 +4059,15 @@ void cpu_physical_memory_unmap(void *buffer, target_phys_addr_t len,
                 access_len -= l;
             }
         }
+        if (xen_mapcache_enabled()) {
+            uint8_t *buffer1 = buffer;
+            uint8_t *end_buffer = buffer + len;
+
+            while (buffer1 < end_buffer) {
+                qemu_put_ram_ptr(buffer1);
+                buffer1 += TARGET_PAGE_SIZE;
+            }
+        }
         return;
     }
     if (is_write) {
diff --git a/hw/boards.h b/hw/boards.h
index 6f0f0d7925..716fd7b1a6 100644
--- a/hw/boards.h
+++ b/hw/boards.h
@@ -27,6 +27,7 @@ typedef struct QEMUMachine {
         no_cdrom:1,
         no_sdcard:1;
     int is_default;
+    const char *default_machine_opts;
     GlobalProperty *compat_props;
     struct QEMUMachine *next;
 } QEMUMachine;
diff --git a/hw/pc.c b/hw/pc.c
index 6939c04560..810619756b 100644
--- a/hw/pc.c
+++ b/hw/pc.c
@@ -957,29 +957,18 @@ void pc_cpus_init(const char *cpu_model)
     }
 }
 
-void pc_memory_init(ram_addr_t ram_size,
-                    const char *kernel_filename,
+void pc_memory_init(const char *kernel_filename,
                     const char *kernel_cmdline,
                     const char *initrd_filename,
-                    ram_addr_t *below_4g_mem_size_p,
-                    ram_addr_t *above_4g_mem_size_p)
+                    ram_addr_t below_4g_mem_size,
+                    ram_addr_t above_4g_mem_size)
 {
     char *filename;
     int ret, linux_boot, i;
     ram_addr_t ram_addr, bios_offset, option_rom_offset;
-    ram_addr_t below_4g_mem_size, above_4g_mem_size = 0;
     int bios_size, isa_bios_size;
     void *fw_cfg;
 
-    if (ram_size >= 0xe0000000 ) {
-        above_4g_mem_size = ram_size - 0xe0000000;
-        below_4g_mem_size = 0xe0000000;
-    } else {
-        below_4g_mem_size = ram_size;
-    }
-    *above_4g_mem_size_p = above_4g_mem_size;
-    *below_4g_mem_size_p = below_4g_mem_size;
-
     linux_boot = (kernel_filename != NULL);
 
     /* allocate RAM */
@@ -1093,7 +1082,8 @@ static void cpu_request_exit(void *opaque, int irq, int level)
 }
 
 void pc_basic_device_init(qemu_irq *isa_irq,
-                          ISADevice **rtc_state)
+                          ISADevice **rtc_state,
+                          bool no_vmport)
 {
     int i;
     DriveInfo *fd[MAX_FD];
@@ -1138,8 +1128,12 @@ void pc_basic_device_init(qemu_irq *isa_irq,
     a20_line = qemu_allocate_irqs(handle_a20_line_change, first_cpu, 2);
     i8042 = isa_create_simple("i8042");
     i8042_setup_a20_line(i8042, &a20_line[0]);
-    vmport_init();
-    vmmouse = isa_try_create("vmmouse");
+    if (!no_vmport) {
+        vmport_init();
+        vmmouse = isa_try_create("vmmouse");
+    } else {
+        vmmouse = NULL;
+    }
     if (vmmouse) {
         qdev_prop_set_ptr(&vmmouse->qdev, "ps2_mouse", i8042);
         qdev_init_nofail(&vmmouse->qdev);
diff --git a/hw/pc.h b/hw/pc.h
index feb8a7a684..0dcbee7ca5 100644
--- a/hw/pc.h
+++ b/hw/pc.h
@@ -129,16 +129,16 @@ void pc_cmos_set_s3_resume(void *opaque, int irq, int level);
 void pc_acpi_smi_interrupt(void *opaque, int irq, int level);
 
 void pc_cpus_init(const char *cpu_model);
-void pc_memory_init(ram_addr_t ram_size,
-                    const char *kernel_filename,
+void pc_memory_init(const char *kernel_filename,
                     const char *kernel_cmdline,
                     const char *initrd_filename,
-                    ram_addr_t *below_4g_mem_size_p,
-                    ram_addr_t *above_4g_mem_size_p);
+                    ram_addr_t below_4g_mem_size,
+                    ram_addr_t above_4g_mem_size);
 qemu_irq *pc_allocate_cpu_irq(void);
 void pc_vga_init(PCIBus *pci_bus);
 void pc_basic_device_init(qemu_irq *isa_irq,
-                          ISADevice **rtc_state);
+                          ISADevice **rtc_state,
+                          bool no_vmport);
 void pc_init_ne2k_isa(NICInfo *nd);
 void pc_cmos_init(ram_addr_t ram_size, ram_addr_t above_4g_mem_size,
                   const char *boot_device,
@@ -176,6 +176,7 @@ struct PCII440FXState;
 typedef struct PCII440FXState PCII440FXState;
 
 PCIBus *i440fx_init(PCII440FXState **pi440fx_state, int *piix_devfn, qemu_irq *pic, ram_addr_t ram_size);
+PCIBus *i440fx_xen_init(PCII440FXState **pi440fx_state, int *piix3_devfn, qemu_irq *pic, ram_addr_t ram_size);
 void i440fx_init_memory_mappings(PCII440FXState *d);
 
 /* piix4.c */
diff --git a/hw/pc_piix.c b/hw/pc_piix.c
index a85214b7f1..9a22a8afc8 100644
--- a/hw/pc_piix.c
+++ b/hw/pc_piix.c
@@ -38,6 +38,10 @@
 #include "arch_init.h"
 #include "blockdev.h"
 #include "smbus.h"
+#include "xen.h"
+#ifdef CONFIG_XEN
+#  include <xen/hvm/hvm_info_table.h>
+#endif
 
 #define MAX_IDE_BUS 2
 
@@ -92,12 +96,26 @@ static void pc_init1(ram_addr_t ram_size,
         kvmclock_create();
     }
 
+    if (ram_size >= 0xe0000000 ) {
+        above_4g_mem_size = ram_size - 0xe0000000;
+        below_4g_mem_size = 0xe0000000;
+    } else {
+        above_4g_mem_size = 0;
+        below_4g_mem_size = ram_size;
+    }
+
     /* allocate ram and load rom/bios */
-    pc_memory_init(ram_size, kernel_filename, kernel_cmdline, initrd_filename,
-                   &below_4g_mem_size, &above_4g_mem_size);
+    if (!xen_enabled()) {
+        pc_memory_init(kernel_filename, kernel_cmdline, initrd_filename,
+                       below_4g_mem_size, above_4g_mem_size);
+    }
 
-    cpu_irq = pc_allocate_cpu_irq();
-    i8259 = i8259_init(cpu_irq[0]);
+    if (!xen_enabled()) {
+        cpu_irq = pc_allocate_cpu_irq();
+        i8259 = i8259_init(cpu_irq[0]);
+    } else {
+        i8259 = xen_interrupt_controller_init();
+    }
     isa_irq_state = qemu_mallocz(sizeof(*isa_irq_state));
     isa_irq_state->i8259 = i8259;
     if (pci_enabled) {
@@ -106,7 +124,11 @@ static void pc_init1(ram_addr_t ram_size,
     isa_irq = qemu_allocate_irqs(isa_irq_handler, isa_irq_state, 24);
 
     if (pci_enabled) {
-        pci_bus = i440fx_init(&i440fx_state, &piix3_devfn, isa_irq, ram_size);
+        if (!xen_enabled()) {
+            pci_bus = i440fx_init(&i440fx_state, &piix3_devfn, isa_irq, ram_size);
+        } else {
+            pci_bus = i440fx_xen_init(&i440fx_state, &piix3_devfn, isa_irq, ram_size);
+        }
     } else {
         pci_bus = NULL;
         i440fx_state = NULL;
@@ -119,7 +141,7 @@ static void pc_init1(ram_addr_t ram_size,
     pc_vga_init(pci_enabled? pci_bus: NULL);
 
     /* init basic PC hardware */
-    pc_basic_device_init(isa_irq, &rtc_state);
+    pc_basic_device_init(isa_irq, &rtc_state, xen_enabled());
 
     for(i = 0; i < nb_nics; i++) {
         NICInfo *nd = &nd_table[i];
@@ -157,7 +179,11 @@ static void pc_init1(ram_addr_t ram_size,
     if (pci_enabled && acpi_enabled) {
         i2c_bus *smbus;
 
-        cmos_s3 = qemu_allocate_irqs(pc_cmos_set_s3_resume, rtc_state, 1);
+        if (!xen_enabled()) {
+            cmos_s3 = qemu_allocate_irqs(pc_cmos_set_s3_resume, rtc_state, 1);
+        } else {
+            cmos_s3 = qemu_allocate_irqs(xen_cmos_set_s3_resume, rtc_state, 1);
+        }
         smi_irq = qemu_allocate_irqs(pc_acpi_smi_interrupt, first_cpu, 1);
         /* TODO: Populate SPD eeprom data.  */
         smbus = piix4_pm_init(pci_bus, piix3_devfn + 3, 0xb100,
@@ -213,6 +239,24 @@ static void pc_init_isa(ram_addr_t ram_size,
              initrd_filename, cpu_model, 0, 1);
 }
 
+#ifdef CONFIG_XEN
+static void pc_xen_hvm_init(ram_addr_t ram_size,
+                            const char *boot_device,
+                            const char *kernel_filename,
+                            const char *kernel_cmdline,
+                            const char *initrd_filename,
+                            const char *cpu_model)
+{
+    if (xen_hvm_init() != 0) {
+        hw_error("xen hardware virtual machine initialisation failed");
+    }
+    pc_init_pci_no_kvmclock(ram_size, boot_device,
+                            kernel_filename, kernel_cmdline,
+                            initrd_filename, cpu_model);
+    xen_vcpu_init();
+}
+#endif
+
 static QEMUMachine pc_machine = {
     .name = "pc-0.14",
     .alias = "pc",
@@ -377,6 +421,16 @@ static QEMUMachine isapc_machine = {
     .max_cpus = 1,
 };
 
+#ifdef CONFIG_XEN
+static QEMUMachine xenfv_machine = {
+    .name = "xenfv",
+    .desc = "Xen Fully-virtualized PC",
+    .init = pc_xen_hvm_init,
+    .max_cpus = HVM_MAX_VCPUS,
+    .default_machine_opts = "accel=xen",
+};
+#endif
+
 static void pc_machine_init(void)
 {
     qemu_register_machine(&pc_machine);
@@ -385,6 +439,9 @@ static void pc_machine_init(void)
     qemu_register_machine(&pc_machine_v0_11);
     qemu_register_machine(&pc_machine_v0_10);
     qemu_register_machine(&isapc_machine);
+#ifdef CONFIG_XEN
+    qemu_register_machine(&xenfv_machine);
+#endif
 }
 
 machine_init(pc_machine_init);
diff --git a/hw/pci.c b/hw/pci.c
index 0875654253..631d77cccb 100644
--- a/hw/pci.c
+++ b/hw/pci.c
@@ -1922,6 +1922,8 @@ static int pci_add_option_rom(PCIDevice *pdev, bool is_default_rom)
         pci_patch_ids(pdev, ptr, size);
     }
 
+    qemu_put_ram_ptr(ptr);
+
     pci_register_bar(pdev, PCI_ROM_SLOT, size,
                      0, pci_map_option_rom);
 
diff --git a/hw/piix_pci.c b/hw/piix_pci.c
index 5f0d92f10d..7f1c4cca31 100644
--- a/hw/piix_pci.c
+++ b/hw/piix_pci.c
@@ -29,6 +29,7 @@
 #include "isa.h"
 #include "sysbus.h"
 #include "range.h"
+#include "xen.h"
 
 /*
  * I440FX chipset data sheet.
@@ -172,6 +173,13 @@ static void i440fx_write_config(PCIDevice *dev,
     }
 }
 
+static void i440fx_write_config_xen(PCIDevice *dev,
+                                    uint32_t address, uint32_t val, int len)
+{
+    xen_piix_pci_write_config_client(address, val, len);
+    i440fx_write_config(dev, address, val, len);
+}
+
 static int i440fx_load_old(QEMUFile* f, void *opaque, int version_id)
 {
     PCII440FXState *d = opaque;
@@ -239,7 +247,10 @@ static int i440fx_initfn(PCIDevice *dev)
     return 0;
 }
 
-PCIBus *i440fx_init(PCII440FXState **pi440fx_state, int *piix3_devfn, qemu_irq *pic, ram_addr_t ram_size)
+static PCIBus *i440fx_common_init(const char *device_name,
+                                  PCII440FXState **pi440fx_state,
+                                  int *piix3_devfn,
+                                  qemu_irq *pic, ram_addr_t ram_size)
 {
     DeviceState *dev;
     PCIBus *b;
@@ -253,13 +264,13 @@ PCIBus *i440fx_init(PCII440FXState **pi440fx_state, int *piix3_devfn, qemu_irq *
     s->bus = b;
     qdev_init_nofail(dev);
 
-    d = pci_create_simple(b, 0, "i440FX");
+    d = pci_create_simple(b, 0, device_name);
     *pi440fx_state = DO_UPCAST(PCII440FXState, dev, d);
 
     piix3 = DO_UPCAST(PIIX3State, dev,
                       pci_create_simple_multifunction(b, -1, true, "PIIX3"));
     piix3->pic = pic;
-    pci_bus_irqs(b, piix3_set_irq, pci_slot_get_pirq, piix3, PIIX_NUM_PIRQS);
+
     (*pi440fx_state)->piix3 = piix3;
 
     *piix3_devfn = piix3->dev.devfn;
@@ -272,6 +283,30 @@ PCIBus *i440fx_init(PCII440FXState **pi440fx_state, int *piix3_devfn, qemu_irq *
     return b;
 }
 
+PCIBus *i440fx_init(PCII440FXState **pi440fx_state, int *piix3_devfn,
+                    qemu_irq *pic, ram_addr_t ram_size)
+{
+    PCIBus *b;
+
+    b = i440fx_common_init("i440FX", pi440fx_state, piix3_devfn, pic, ram_size);
+    pci_bus_irqs(b, piix3_set_irq, pci_slot_get_pirq, (*pi440fx_state)->piix3,
+                 PIIX_NUM_PIRQS);
+
+    return b;
+}
+
+PCIBus *i440fx_xen_init(PCII440FXState **pi440fx_state, int *piix3_devfn,
+                        qemu_irq *pic, ram_addr_t ram_size)
+{
+    PCIBus *b;
+
+    b = i440fx_common_init("i440FX-xen", pi440fx_state, piix3_devfn, pic, ram_size);
+    pci_bus_irqs(b, xen_piix3_set_irq, xen_pci_slot_get_pirq,
+                 (*pi440fx_state)->piix3, PIIX_NUM_PIRQS);
+
+    return b;
+}
+
 /* PIIX3 PCI to ISA bridge */
 static void piix3_set_irq_pic(PIIX3State *piix3, int pic_irq)
 {
@@ -430,6 +465,14 @@ static PCIDeviceInfo i440fx_info[] = {
         .init         = i440fx_initfn,
         .config_write = i440fx_write_config,
     },{
+        .qdev.name    = "i440FX-xen",
+        .qdev.desc    = "Host bridge",
+        .qdev.size    = sizeof(PCII440FXState),
+        .qdev.vmsd    = &vmstate_i440fx,
+        .qdev.no_user = 1,
+        .init         = i440fx_initfn,
+        .config_write = i440fx_write_config_xen,
+    },{
         .qdev.name    = "PIIX3",
         .qdev.desc    = "ISA bridge",
         .qdev.size    = sizeof(PIIX3State),
diff --git a/hw/xen.h b/hw/xen.h
index 780dcf713a..d435ca0ce5 100644
--- a/hw/xen.h
+++ b/hw/xen.h
@@ -8,6 +8,8 @@
  */
 #include <inttypes.h>
 
+#include "qemu-common.h"
+
 /* xen-machine.c */
 enum xen_mode {
     XEN_EMULATE = 0,  // xen emulation, using xenner (default)
@@ -18,4 +20,43 @@ enum xen_mode {
 extern uint32_t xen_domid;
 extern enum xen_mode xen_mode;
 
+extern int xen_allowed;
+
+static inline int xen_enabled(void)
+{
+#ifdef CONFIG_XEN
+    return xen_allowed;
+#else
+    return 0;
+#endif
+}
+
+static inline int xen_mapcache_enabled(void)
+{
+#ifdef CONFIG_XEN_MAPCACHE
+    return xen_enabled();
+#else
+    return 0;
+#endif
+}
+
+int xen_pci_slot_get_pirq(PCIDevice *pci_dev, int irq_num);
+void xen_piix3_set_irq(void *opaque, int irq_num, int level);
+void xen_piix_pci_write_config_client(uint32_t address, uint32_t val, int len);
+void xen_cmos_set_s3_resume(void *opaque, int irq, int level);
+
+qemu_irq *xen_interrupt_controller_init(void);
+
+int xen_init(void);
+int xen_hvm_init(void);
+void xen_vcpu_init(void);
+
+#if defined(NEED_CPU_H) && !defined(CONFIG_USER_ONLY)
+void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size);
+#endif
+
+#if defined(CONFIG_XEN) && CONFIG_XEN_CTRL_INTERFACE_VERSION < 400
+#  define HVM_MAX_VCPUS 32
+#endif
+
 #endif /* QEMU_HW_XEN_H */
diff --git a/hw/xen_backend.c b/hw/xen_backend.c
index a2e408fa0e..d881fa2f70 100644
--- a/hw/xen_backend.c
+++ b/hw/xen_backend.c
@@ -43,7 +43,8 @@
 /* ------------------------------------------------------------- */
 
 /* public */
-int xen_xc;
+XenXC xen_xc = XC_HANDLER_INITIAL_VALUE;
+XenGnttab xen_xcg = XC_HANDLER_INITIAL_VALUE;
 struct xs_handle *xenstore = NULL;
 const char *xen_protocol;
 
@@ -58,8 +59,9 @@ int xenstore_write_str(const char *base, const char *node, const char *val)
     char abspath[XEN_BUFSIZE];
 
     snprintf(abspath, sizeof(abspath), "%s/%s", base, node);
-    if (!xs_write(xenstore, 0, abspath, val, strlen(val)))
-	return -1;
+    if (!xs_write(xenstore, 0, abspath, val, strlen(val))) {
+        return -1;
+    }
     return 0;
 }
 
@@ -94,8 +96,9 @@ int xenstore_read_int(const char *base, const char *node, int *ival)
     int rc = -1;
 
     val = xenstore_read_str(base, node);
-    if (val && 1 == sscanf(val, "%d", ival))
-	rc = 0;
+    if (val && 1 == sscanf(val, "%d", ival)) {
+        rc = 0;
+    }
     qemu_free(val);
     return rc;
 }
@@ -134,16 +137,16 @@ int xenstore_read_fe_int(struct XenDevice *xendev, const char *node, int *ival)
 
 const char *xenbus_strstate(enum xenbus_state state)
 {
-	static const char *const name[] = {
-		[ XenbusStateUnknown      ] = "Unknown",
-		[ XenbusStateInitialising ] = "Initialising",
-		[ XenbusStateInitWait     ] = "InitWait",
-		[ XenbusStateInitialised  ] = "Initialised",
-		[ XenbusStateConnected    ] = "Connected",
-		[ XenbusStateClosing      ] = "Closing",
-		[ XenbusStateClosed	  ] = "Closed",
-	};
-	return (state < ARRAY_SIZE(name)) ? name[state] : "INVALID";
+    static const char *const name[] = {
+        [ XenbusStateUnknown      ] = "Unknown",
+        [ XenbusStateInitialising ] = "Initialising",
+        [ XenbusStateInitWait     ] = "InitWait",
+        [ XenbusStateInitialised  ] = "Initialised",
+        [ XenbusStateConnected    ] = "Connected",
+        [ XenbusStateClosing      ] = "Closing",
+        [ XenbusStateClosed       ] = "Closed",
+    };
+    return (state < ARRAY_SIZE(name)) ? name[state] : "INVALID";
 }
 
 int xen_be_set_state(struct XenDevice *xendev, enum xenbus_state state)
@@ -151,10 +154,11 @@ int xen_be_set_state(struct XenDevice *xendev, enum xenbus_state state)
     int rc;
 
     rc = xenstore_write_be_int(xendev, "state", state);
-    if (rc < 0)
-	return rc;
+    if (rc < 0) {
+        return rc;
+    }
     xen_be_printf(xendev, 1, "backend state: %s -> %s\n",
-		  xenbus_strstate(xendev->be_state), xenbus_strstate(state));
+                  xenbus_strstate(xendev->be_state), xenbus_strstate(state));
     xendev->be_state = state;
     return 0;
 }
@@ -166,13 +170,16 @@ struct XenDevice *xen_be_find_xendev(const char *type, int dom, int dev)
     struct XenDevice *xendev;
 
     QTAILQ_FOREACH(xendev, &xendevs, next) {
-	if (xendev->dom != dom)
-	    continue;
-	if (xendev->dev != dev)
-	    continue;
-	if (strcmp(xendev->type, type) != 0)
-	    continue;
-	return xendev;
+        if (xendev->dom != dom) {
+            continue;
+        }
+        if (xendev->dev != dev) {
+            continue;
+        }
+        if (strcmp(xendev->type, type) != 0) {
+            continue;
+        }
+        return xendev;
     }
     return NULL;
 }
@@ -187,8 +194,9 @@ static struct XenDevice *xen_be_get_xendev(const char *type, int dom, int dev,
     char *dom0;
 
     xendev = xen_be_find_xendev(type, dom, dev);
-    if (xendev)
-	return xendev;
+    if (xendev) {
+        return xendev;
+    }
 
     /* init new xendev */
     xendev = qemu_mallocz(ops->size);
@@ -199,38 +207,39 @@ static struct XenDevice *xen_be_get_xendev(const char *type, int dom, int dev,
 
     dom0 = xs_get_domain_path(xenstore, 0);
     snprintf(xendev->be, sizeof(xendev->be), "%s/backend/%s/%d/%d",
-	     dom0, xendev->type, xendev->dom, xendev->dev);
+             dom0, xendev->type, xendev->dom, xendev->dev);
     snprintf(xendev->name, sizeof(xendev->name), "%s-%d",
-	     xendev->type, xendev->dev);
+             xendev->type, xendev->dev);
     free(dom0);
 
     xendev->debug      = debug;
     xendev->local_port = -1;
 
-    xendev->evtchndev = xc_evtchn_open();
-    if (xendev->evtchndev < 0) {
-	xen_be_printf(NULL, 0, "can't open evtchn device\n");
-	qemu_free(xendev);
-	return NULL;
+    xendev->evtchndev = xen_xc_evtchn_open(NULL, 0);
+    if (xendev->evtchndev == XC_HANDLER_INITIAL_VALUE) {
+        xen_be_printf(NULL, 0, "can't open evtchn device\n");
+        qemu_free(xendev);
+        return NULL;
     }
     fcntl(xc_evtchn_fd(xendev->evtchndev), F_SETFD, FD_CLOEXEC);
 
     if (ops->flags & DEVOPS_FLAG_NEED_GNTDEV) {
-	xendev->gnttabdev = xc_gnttab_open();
-	if (xendev->gnttabdev < 0) {
-	    xen_be_printf(NULL, 0, "can't open gnttab device\n");
-	    xc_evtchn_close(xendev->evtchndev);
-	    qemu_free(xendev);
-	    return NULL;
-	}
+        xendev->gnttabdev = xen_xc_gnttab_open(NULL, 0);
+        if (xendev->gnttabdev == XC_HANDLER_INITIAL_VALUE) {
+            xen_be_printf(NULL, 0, "can't open gnttab device\n");
+            xc_evtchn_close(xendev->evtchndev);
+            qemu_free(xendev);
+            return NULL;
+        }
     } else {
-	xendev->gnttabdev = -1;
+        xendev->gnttabdev = XC_HANDLER_INITIAL_VALUE;
     }
 
     QTAILQ_INSERT_TAIL(&xendevs, xendev, next);
 
-    if (xendev->ops->alloc)
-	xendev->ops->alloc(xendev);
+    if (xendev->ops->alloc) {
+        xendev->ops->alloc(xendev);
+    }
 
     return xendev;
 }
@@ -251,28 +260,33 @@ static struct XenDevice *xen_be_del_xendev(int dom, int dev)
         xendev = xnext;
         xnext = xendev->next.tqe_next;
 
-	if (xendev->dom != dom)
-	    continue;
-	if (xendev->dev != dev && dev != -1)
-	    continue;
-
-	if (xendev->ops->free)
-	    xendev->ops->free(xendev);
-
-	if (xendev->fe) {
-	    char token[XEN_BUFSIZE];
-	    snprintf(token, sizeof(token), "fe:%p", xendev);
-	    xs_unwatch(xenstore, xendev->fe, token);
-	    qemu_free(xendev->fe);
-	}
-
-	if (xendev->evtchndev >= 0)
-	    xc_evtchn_close(xendev->evtchndev);
-	if (xendev->gnttabdev >= 0)
-	    xc_gnttab_close(xendev->gnttabdev);
-
-	QTAILQ_REMOVE(&xendevs, xendev, next);
-	qemu_free(xendev);
+        if (xendev->dom != dom) {
+            continue;
+        }
+        if (xendev->dev != dev && dev != -1) {
+            continue;
+        }
+
+        if (xendev->ops->free) {
+            xendev->ops->free(xendev);
+        }
+
+        if (xendev->fe) {
+            char token[XEN_BUFSIZE];
+            snprintf(token, sizeof(token), "fe:%p", xendev);
+            xs_unwatch(xenstore, xendev->fe, token);
+            qemu_free(xendev->fe);
+        }
+
+        if (xendev->evtchndev != XC_HANDLER_INITIAL_VALUE) {
+            xc_evtchn_close(xendev->evtchndev);
+        }
+        if (xendev->gnttabdev != XC_HANDLER_INITIAL_VALUE) {
+            xc_gnttab_close(xendev->gnttabdev);
+        }
+
+        QTAILQ_REMOVE(&xendevs, xendev, next);
+        qemu_free(xendev);
     }
     return NULL;
 }
@@ -285,14 +299,16 @@ static struct XenDevice *xen_be_del_xendev(int dom, int dev)
 static void xen_be_backend_changed(struct XenDevice *xendev, const char *node)
 {
     if (node == NULL  ||  strcmp(node, "online") == 0) {
-	if (xenstore_read_be_int(xendev, "online", &xendev->online) == -1)
-	    xendev->online = 0;
+        if (xenstore_read_be_int(xendev, "online", &xendev->online) == -1) {
+            xendev->online = 0;
+        }
     }
 
     if (node) {
-	xen_be_printf(xendev, 2, "backend update: %s\n", node);
-	if (xendev->ops->backend_changed)
-	    xendev->ops->backend_changed(xendev, node);
+        xen_be_printf(xendev, 2, "backend update: %s\n", node);
+        if (xendev->ops->backend_changed) {
+            xendev->ops->backend_changed(xendev, node);
+        }
     }
 }
 
@@ -301,25 +317,29 @@ static void xen_be_frontend_changed(struct XenDevice *xendev, const char *node)
     int fe_state;
 
     if (node == NULL  ||  strcmp(node, "state") == 0) {
-	if (xenstore_read_fe_int(xendev, "state", &fe_state) == -1)
-	    fe_state = XenbusStateUnknown;
-	if (xendev->fe_state != fe_state)
-	    xen_be_printf(xendev, 1, "frontend state: %s -> %s\n",
-			  xenbus_strstate(xendev->fe_state),
-			  xenbus_strstate(fe_state));
-	xendev->fe_state = fe_state;
+        if (xenstore_read_fe_int(xendev, "state", &fe_state) == -1) {
+            fe_state = XenbusStateUnknown;
+        }
+        if (xendev->fe_state != fe_state) {
+            xen_be_printf(xendev, 1, "frontend state: %s -> %s\n",
+                          xenbus_strstate(xendev->fe_state),
+                          xenbus_strstate(fe_state));
+        }
+        xendev->fe_state = fe_state;
     }
     if (node == NULL  ||  strcmp(node, "protocol") == 0) {
-	qemu_free(xendev->protocol);
-	xendev->protocol = xenstore_read_fe_str(xendev, "protocol");
-	if (xendev->protocol)
-	    xen_be_printf(xendev, 1, "frontend protocol: %s\n", xendev->protocol);
+        qemu_free(xendev->protocol);
+        xendev->protocol = xenstore_read_fe_str(xendev, "protocol");
+        if (xendev->protocol) {
+            xen_be_printf(xendev, 1, "frontend protocol: %s\n", xendev->protocol);
+        }
     }
 
     if (node) {
-	xen_be_printf(xendev, 2, "frontend update: %s\n", node);
-	if (xendev->ops->frontend_changed)
-	    xendev->ops->frontend_changed(xendev, node);
+        xen_be_printf(xendev, 2, "frontend update: %s\n", node);
+        if (xendev->ops->frontend_changed) {
+            xendev->ops->frontend_changed(xendev, node);
+        }
     }
 }
 
@@ -340,28 +360,28 @@ static int xen_be_try_setup(struct XenDevice *xendev)
     int be_state;
 
     if (xenstore_read_be_int(xendev, "state", &be_state) == -1) {
-	xen_be_printf(xendev, 0, "reading backend state failed\n");
-	return -1;
+        xen_be_printf(xendev, 0, "reading backend state failed\n");
+        return -1;
     }
 
     if (be_state != XenbusStateInitialising) {
-	xen_be_printf(xendev, 0, "initial backend state is wrong (%s)\n",
-		      xenbus_strstate(be_state));
-	return -1;
+        xen_be_printf(xendev, 0, "initial backend state is wrong (%s)\n",
+                      xenbus_strstate(be_state));
+        return -1;
     }
 
     xendev->fe = xenstore_read_be_str(xendev, "frontend");
     if (xendev->fe == NULL) {
-	xen_be_printf(xendev, 0, "reading frontend path failed\n");
-	return -1;
+        xen_be_printf(xendev, 0, "reading frontend path failed\n");
+        return -1;
     }
 
     /* setup frontend watch */
     snprintf(token, sizeof(token), "fe:%p", xendev);
     if (!xs_watch(xenstore, xendev->fe, token)) {
-	xen_be_printf(xendev, 0, "watching frontend path (%s) failed\n",
-		      xendev->fe);
-	return -1;
+        xen_be_printf(xendev, 0, "watching frontend path (%s) failed\n",
+                      xendev->fe);
+        return -1;
     }
     xen_be_set_state(xendev, XenbusStateInitialising);
 
@@ -383,15 +403,16 @@ static int xen_be_try_init(struct XenDevice *xendev)
     int rc = 0;
 
     if (!xendev->online) {
-	xen_be_printf(xendev, 1, "not online\n");
-	return -1;
+        xen_be_printf(xendev, 1, "not online\n");
+        return -1;
     }
 
-    if (xendev->ops->init)
-	rc = xendev->ops->init(xendev);
+    if (xendev->ops->init) {
+        rc = xendev->ops->init(xendev);
+    }
     if (rc != 0) {
-	xen_be_printf(xendev, 1, "init() failed\n");
-	return rc;
+        xen_be_printf(xendev, 1, "init() failed\n");
+        return rc;
     }
 
     xenstore_write_be_str(xendev, "hotplug-status", "connected");
@@ -411,20 +432,21 @@ static int xen_be_try_connect(struct XenDevice *xendev)
     int rc = 0;
 
     if (xendev->fe_state != XenbusStateInitialised  &&
-	xendev->fe_state != XenbusStateConnected) {
-	if (xendev->ops->flags & DEVOPS_FLAG_IGNORE_STATE) {
-	    xen_be_printf(xendev, 2, "frontend not ready, ignoring\n");
-	} else {
-	    xen_be_printf(xendev, 2, "frontend not ready (yet)\n");
-	    return -1;
-	}
+        xendev->fe_state != XenbusStateConnected) {
+        if (xendev->ops->flags & DEVOPS_FLAG_IGNORE_STATE) {
+            xen_be_printf(xendev, 2, "frontend not ready, ignoring\n");
+        } else {
+            xen_be_printf(xendev, 2, "frontend not ready (yet)\n");
+            return -1;
+        }
     }
 
-    if (xendev->ops->connect)
-	rc = xendev->ops->connect(xendev);
+    if (xendev->ops->connect) {
+        rc = xendev->ops->connect(xendev);
+    }
     if (rc != 0) {
-	xen_be_printf(xendev, 0, "connect() failed\n");
-	return rc;
+        xen_be_printf(xendev, 0, "connect() failed\n");
+        return rc;
     }
 
     xen_be_set_state(xendev, XenbusStateConnected);
@@ -440,10 +462,12 @@ static void xen_be_disconnect(struct XenDevice *xendev, enum xenbus_state state)
 {
     if (xendev->be_state != XenbusStateClosing &&
         xendev->be_state != XenbusStateClosed  &&
-        xendev->ops->disconnect)
-	xendev->ops->disconnect(xendev);
-    if (xendev->be_state != state)
+        xendev->ops->disconnect) {
+        xendev->ops->disconnect(xendev);
+    }
+    if (xendev->be_state != state) {
         xen_be_set_state(xendev, state);
+    }
 }
 
 /*
@@ -451,8 +475,9 @@ static void xen_be_disconnect(struct XenDevice *xendev, enum xenbus_state state)
  */
 static int xen_be_try_reset(struct XenDevice *xendev)
 {
-    if (xendev->fe_state != XenbusStateInitialising)
+    if (xendev->fe_state != XenbusStateInitialising) {
         return -1;
+    }
 
     xen_be_printf(xendev, 1, "device reset (for re-connect)\n");
     xen_be_set_state(xendev, XenbusStateInitialising);
@@ -468,31 +493,32 @@ void xen_be_check_state(struct XenDevice *xendev)
 
     /* frontend may request shutdown from almost anywhere */
     if (xendev->fe_state == XenbusStateClosing ||
-	xendev->fe_state == XenbusStateClosed) {
-	xen_be_disconnect(xendev, xendev->fe_state);
-	return;
+        xendev->fe_state == XenbusStateClosed) {
+        xen_be_disconnect(xendev, xendev->fe_state);
+        return;
     }
 
     /* check for possible backend state transitions */
     for (;;) {
-	switch (xendev->be_state) {
-	case XenbusStateUnknown:
-	    rc = xen_be_try_setup(xendev);
-	    break;
-	case XenbusStateInitialising:
-	    rc = xen_be_try_init(xendev);
-	    break;
-	case XenbusStateInitWait:
-	    rc = xen_be_try_connect(xendev);
-	    break;
+        switch (xendev->be_state) {
+        case XenbusStateUnknown:
+            rc = xen_be_try_setup(xendev);
+            break;
+        case XenbusStateInitialising:
+            rc = xen_be_try_init(xendev);
+            break;
+        case XenbusStateInitWait:
+            rc = xen_be_try_connect(xendev);
+            break;
         case XenbusStateClosed:
             rc = xen_be_try_reset(xendev);
             break;
-	default:
-	    rc = -1;
-	}
-	if (rc != 0)
-	    break;
+        default:
+            rc = -1;
+        }
+        if (rc != 0) {
+            break;
+        }
     }
 }
 
@@ -511,26 +537,28 @@ static int xenstore_scan(const char *type, int dom, struct XenDevOps *ops)
     snprintf(path, sizeof(path), "%s/backend/%s/%d", dom0, type, dom);
     free(dom0);
     if (!xs_watch(xenstore, path, token)) {
-	xen_be_printf(NULL, 0, "xen be: watching backend path (%s) failed\n", path);
-	return -1;
+        xen_be_printf(NULL, 0, "xen be: watching backend path (%s) failed\n", path);
+        return -1;
     }
 
     /* look for backends */
     dev = xs_directory(xenstore, 0, path, &cdev);
-    if (!dev)
-	return 0;
+    if (!dev) {
+        return 0;
+    }
     for (j = 0; j < cdev; j++) {
-	xendev = xen_be_get_xendev(type, dom, atoi(dev[j]), ops);
-	if (xendev == NULL)
-	    continue;
-	xen_be_check_state(xendev);
+        xendev = xen_be_get_xendev(type, dom, atoi(dev[j]), ops);
+        if (xendev == NULL) {
+            continue;
+        }
+        xen_be_check_state(xendev);
     }
     free(dev);
     return 0;
 }
 
 static void xenstore_update_be(char *watch, char *type, int dom,
-			       struct XenDevOps *ops)
+                               struct XenDevOps *ops)
 {
     struct XenDevice *xendev;
     char path[XEN_BUFSIZE], *dom0;
@@ -539,25 +567,28 @@ static void xenstore_update_be(char *watch, char *type, int dom,
     dom0 = xs_get_domain_path(xenstore, 0);
     len = snprintf(path, sizeof(path), "%s/backend/%s/%d", dom0, type, dom);
     free(dom0);
-    if (strncmp(path, watch, len) != 0)
-	return;
+    if (strncmp(path, watch, len) != 0) {
+        return;
+    }
     if (sscanf(watch+len, "/%u/%255s", &dev, path) != 2) {
-	strcpy(path, "");
-	if (sscanf(watch+len, "/%u", &dev) != 1)
-	    dev = -1;
+        strcpy(path, "");
+        if (sscanf(watch+len, "/%u", &dev) != 1) {
+            dev = -1;
+        }
+    }
+    if (dev == -1) {
+        return;
     }
-    if (dev == -1)
-	return;
 
     if (0) {
-	/* FIXME: detect devices being deleted from xenstore ... */
-	xen_be_del_xendev(dom, dev);
+        /* FIXME: detect devices being deleted from xenstore ... */
+        xen_be_del_xendev(dom, dev);
     }
 
     xendev = xen_be_get_xendev(type, dom, dev, ops);
     if (xendev != NULL) {
-	xen_be_backend_changed(xendev, path);
-	xen_be_check_state(xendev);
+        xen_be_backend_changed(xendev, path);
+        xen_be_check_state(xendev);
     }
 }
 
@@ -567,10 +598,12 @@ static void xenstore_update_fe(char *watch, struct XenDevice *xendev)
     unsigned int len;
 
     len = strlen(xendev->fe);
-    if (strncmp(xendev->fe, watch, len) != 0)
-	return;
-    if (watch[len] != '/')
-	return;
+    if (strncmp(xendev->fe, watch, len) != 0) {
+        return;
+    }
+    if (watch[len] != '/') {
+        return;
+    }
     node = watch + len + 1;
 
     xen_be_frontend_changed(xendev, node);
@@ -584,14 +617,17 @@ static void xenstore_update(void *unused)
     unsigned int dom, count;
 
     vec = xs_read_watch(xenstore, &count);
-    if (vec == NULL)
-	goto cleanup;
+    if (vec == NULL) {
+        goto cleanup;
+    }
 
     if (sscanf(vec[XS_WATCH_TOKEN], "be:%" PRIxPTR ":%d:%" PRIxPTR,
-               &type, &dom, &ops) == 3)
-	xenstore_update_be(vec[XS_WATCH_PATH], (void*)type, dom, (void*)ops);
-    if (sscanf(vec[XS_WATCH_TOKEN], "fe:%" PRIxPTR, &ptr) == 1)
-	xenstore_update_fe(vec[XS_WATCH_PATH], (void*)ptr);
+               &type, &dom, &ops) == 3) {
+        xenstore_update_be(vec[XS_WATCH_PATH], (void*)type, dom, (void*)ops);
+    }
+    if (sscanf(vec[XS_WATCH_TOKEN], "fe:%" PRIxPTR, &ptr) == 1) {
+        xenstore_update_fe(vec[XS_WATCH_PATH], (void*)ptr);
+    }
 
 cleanup:
     free(vec);
@@ -604,14 +640,15 @@ static void xen_be_evtchn_event(void *opaque)
 
     port = xc_evtchn_pending(xendev->evtchndev);
     if (port != xendev->local_port) {
-	xen_be_printf(xendev, 0, "xc_evtchn_pending returned %d (expected %d)\n",
-		      port, xendev->local_port);
-	return;
+        xen_be_printf(xendev, 0, "xc_evtchn_pending returned %d (expected %d)\n",
+                      port, xendev->local_port);
+        return;
     }
     xc_evtchn_unmask(xendev->evtchndev, port);
 
-    if (xendev->ops->event)
-	xendev->ops->event(xendev);
+    if (xendev->ops->event) {
+        xendev->ops->event(xendev);
+    }
 }
 
 /* -------------------------------------------------------------------- */
@@ -620,17 +657,17 @@ int xen_be_init(void)
 {
     xenstore = xs_daemon_open();
     if (!xenstore) {
-	xen_be_printf(NULL, 0, "can't connect to xenstored\n");
-	return -1;
+        xen_be_printf(NULL, 0, "can't connect to xenstored\n");
+        return -1;
     }
 
-    if (qemu_set_fd_handler(xs_fileno(xenstore), xenstore_update, NULL, NULL) < 0)
-	goto err;
+    if (qemu_set_fd_handler(xs_fileno(xenstore), xenstore_update, NULL, NULL) < 0) {
+        goto err;
+    }
 
-    xen_xc = xc_interface_open();
-    if (xen_xc == -1) {
-	xen_be_printf(NULL, 0, "can't open xen interface\n");
-	goto err;
+    if (xen_xc == XC_HANDLER_INITIAL_VALUE) {
+        /* Check if xen_init() have been called */
+        goto err;
     }
     return 0;
 
@@ -649,24 +686,26 @@ int xen_be_register(const char *type, struct XenDevOps *ops)
 
 int xen_be_bind_evtchn(struct XenDevice *xendev)
 {
-    if (xendev->local_port != -1)
-	return 0;
+    if (xendev->local_port != -1) {
+        return 0;
+    }
     xendev->local_port = xc_evtchn_bind_interdomain
-	(xendev->evtchndev, xendev->dom, xendev->remote_port);
+        (xendev->evtchndev, xendev->dom, xendev->remote_port);
     if (xendev->local_port == -1) {
-	xen_be_printf(xendev, 0, "xc_evtchn_bind_interdomain failed\n");
-	return -1;
+        xen_be_printf(xendev, 0, "xc_evtchn_bind_interdomain failed\n");
+        return -1;
     }
     xen_be_printf(xendev, 2, "bind evtchn port %d\n", xendev->local_port);
     qemu_set_fd_handler(xc_evtchn_fd(xendev->evtchndev),
-			xen_be_evtchn_event, NULL, xendev);
+                        xen_be_evtchn_event, NULL, xendev);
     return 0;
 }
 
 void xen_be_unbind_evtchn(struct XenDevice *xendev)
 {
-    if (xendev->local_port == -1)
-	return;
+    if (xendev->local_port == -1) {
+        return;
+    }
     qemu_set_fd_handler(xc_evtchn_fd(xendev->evtchndev), NULL, NULL, NULL);
     xc_evtchn_unbind(xendev->evtchndev, xendev->local_port);
     xen_be_printf(xendev, 2, "unbind evtchn port %d\n", xendev->local_port);
@@ -690,17 +729,21 @@ void xen_be_printf(struct XenDevice *xendev, int msg_level, const char *fmt, ...
     va_list args;
 
     if (xendev) {
-        if (msg_level > xendev->debug)
+        if (msg_level > xendev->debug) {
             return;
+        }
         qemu_log("xen be: %s: ", xendev->name);
-        if (msg_level == 0)
+        if (msg_level == 0) {
             fprintf(stderr, "xen be: %s: ", xendev->name);
+        }
     } else {
-        if (msg_level > debug)
+        if (msg_level > debug) {
             return;
+        }
         qemu_log("xen be core: ");
-        if (msg_level == 0)
+        if (msg_level == 0) {
             fprintf(stderr, "xen be core: ");
+        }
     }
     va_start(args, fmt);
     qemu_log_vprintf(fmt, args);
diff --git a/hw/xen_backend.h b/hw/xen_backend.h
index 1b428e3bf4..6401c85a7e 100644
--- a/hw/xen_backend.h
+++ b/hw/xen_backend.h
@@ -45,8 +45,8 @@ struct XenDevice {
     int                remote_port;
     int                local_port;
 
-    int                evtchndev;
-    int                gnttabdev;
+    XenEvtchn          evtchndev;
+    XenGnttab          gnttabdev;
 
     struct XenDevOps   *ops;
     QTAILQ_ENTRY(XenDevice) next;
@@ -55,7 +55,7 @@ struct XenDevice {
 /* ------------------------------------------------------------- */
 
 /* variables */
-extern int xen_xc;
+extern XenXC xen_xc;
 extern struct xs_handle *xenstore;
 extern const char *xen_protocol;
 
diff --git a/hw/xen_common.h b/hw/xen_common.h
index 8a55b44f0b..a1958a0af1 100644
--- a/hw/xen_common.h
+++ b/hw/xen_common.h
@@ -1,6 +1,8 @@
 #ifndef QEMU_HW_XEN_COMMON_H
 #define QEMU_HW_XEN_COMMON_H 1
 
+#include "config-host.h"
+
 #include <stddef.h>
 #include <inttypes.h>
 
@@ -13,22 +15,98 @@
 #include "qemu-queue.h"
 
 /*
- * tweaks needed to build with different xen versions
- *  0x00030205 -> 3.1.0
- *  0x00030207 -> 3.2.0
- *  0x00030208 -> unstable
+ * We don't support Xen prior to 3.3.0.
  */
-#include <xen/xen-compat.h>
-#if __XEN_LATEST_INTERFACE_VERSION__ < 0x00030205
-# define evtchn_port_or_error_t int
-#endif
-#if __XEN_LATEST_INTERFACE_VERSION__ < 0x00030207
-# define xc_map_foreign_pages xc_map_foreign_batch
+
+/* Xen before 4.0 */
+#if CONFIG_XEN_CTRL_INTERFACE_VERSION < 400
+static inline void *xc_map_foreign_bulk(int xc_handle, uint32_t dom, int prot,
+                                        xen_pfn_t *arr, int *err,
+                                        unsigned int num)
+{
+    return xc_map_foreign_batch(xc_handle, dom, prot, arr, num);
+}
 #endif
-#if __XEN_LATEST_INTERFACE_VERSION__ < 0x00030208
-# define xen_mb()  mb()
-# define xen_rmb() rmb()
-# define xen_wmb() wmb()
+
+
+/* Xen before 4.1 */
+#if CONFIG_XEN_CTRL_INTERFACE_VERSION < 410
+
+typedef int XenXC;
+typedef int XenEvtchn;
+typedef int XenGnttab;
+
+#  define XC_INTERFACE_FMT "%i"
+#  define XC_HANDLER_INITIAL_VALUE    -1
+
+static inline XenEvtchn xen_xc_evtchn_open(void *logger,
+                                           unsigned int open_flags)
+{
+    return xc_evtchn_open();
+}
+
+static inline XenGnttab xen_xc_gnttab_open(void *logger,
+                                           unsigned int open_flags)
+{
+    return xc_gnttab_open();
+}
+
+static inline XenXC xen_xc_interface_open(void *logger, void *dombuild_logger,
+                                          unsigned int open_flags)
+{
+    return xc_interface_open();
+}
+
+static inline int xc_fd(int xen_xc)
+{
+    return xen_xc;
+}
+
+
+static inline int xc_domain_populate_physmap_exact
+    (XenXC xc_handle, uint32_t domid, unsigned long nr_extents,
+     unsigned int extent_order, unsigned int mem_flags, xen_pfn_t *extent_start)
+{
+    return xc_domain_memory_populate_physmap
+        (xc_handle, domid, nr_extents, extent_order, mem_flags, extent_start);
+}
+
+
+/* Xen 4.1 */
+#else
+
+typedef xc_interface *XenXC;
+typedef xc_evtchn *XenEvtchn;
+typedef xc_gnttab *XenGnttab;
+
+#  define XC_INTERFACE_FMT "%p"
+#  define XC_HANDLER_INITIAL_VALUE    NULL
+
+static inline XenEvtchn xen_xc_evtchn_open(void *logger,
+                                           unsigned int open_flags)
+{
+    return xc_evtchn_open(logger, open_flags);
+}
+
+static inline XenGnttab xen_xc_gnttab_open(void *logger,
+                                           unsigned int open_flags)
+{
+    return xc_gnttab_open(logger, open_flags);
+}
+
+static inline XenXC xen_xc_interface_open(void *logger, void *dombuild_logger,
+                                          unsigned int open_flags)
+{
+    return xc_interface_open(logger, dombuild_logger, open_flags);
+}
+
+/* FIXME There is now way to have the xen fd */
+static inline int xc_fd(xc_interface *xen_xc)
+{
+    return -1;
+}
 #endif
 
+void destroy_hvm_domain(void);
+
 #endif /* QEMU_HW_XEN_COMMON_H */
diff --git a/hw/xen_disk.c b/hw/xen_disk.c
index 558bf8ae25..233c8c99c6 100644
--- a/hw/xen_disk.c
+++ b/hw/xen_disk.c
@@ -120,17 +120,18 @@ static struct ioreq *ioreq_start(struct XenBlkDev *blkdev)
     struct ioreq *ioreq = NULL;
 
     if (QLIST_EMPTY(&blkdev->freelist)) {
-	if (blkdev->requests_total >= max_requests)
-	    goto out;
-	/* allocate new struct */
-	ioreq = qemu_mallocz(sizeof(*ioreq));
-	ioreq->blkdev = blkdev;
-	blkdev->requests_total++;
+        if (blkdev->requests_total >= max_requests) {
+            goto out;
+        }
+        /* allocate new struct */
+        ioreq = qemu_mallocz(sizeof(*ioreq));
+        ioreq->blkdev = blkdev;
+        blkdev->requests_total++;
         qemu_iovec_init(&ioreq->v, BLKIF_MAX_SEGMENTS_PER_REQUEST);
     } else {
-	/* get one from freelist */
-	ioreq = QLIST_FIRST(&blkdev->freelist);
-	QLIST_REMOVE(ioreq, list);
+        /* get one from freelist */
+        ioreq = QLIST_FIRST(&blkdev->freelist);
+        QLIST_REMOVE(ioreq, list);
         qemu_iovec_reset(&ioreq->v);
     }
     QLIST_INSERT_HEAD(&blkdev->inflight, ioreq, list);
@@ -173,30 +174,32 @@ static int ioreq_parse(struct ioreq *ioreq)
     int i;
 
     xen_be_printf(&blkdev->xendev, 3,
-		  "op %d, nr %d, handle %d, id %" PRId64 ", sector %" PRId64 "\n",
-		  ioreq->req.operation, ioreq->req.nr_segments,
-		  ioreq->req.handle, ioreq->req.id, ioreq->req.sector_number);
+                  "op %d, nr %d, handle %d, id %" PRId64 ", sector %" PRId64 "\n",
+                  ioreq->req.operation, ioreq->req.nr_segments,
+                  ioreq->req.handle, ioreq->req.id, ioreq->req.sector_number);
     switch (ioreq->req.operation) {
     case BLKIF_OP_READ:
-	ioreq->prot = PROT_WRITE; /* to memory */
-	break;
+        ioreq->prot = PROT_WRITE; /* to memory */
+        break;
     case BLKIF_OP_WRITE_BARRIER:
         if (!ioreq->req.nr_segments) {
             ioreq->presync = 1;
             return 0;
         }
-	if (!syncwrite)
-	    ioreq->presync = ioreq->postsync = 1;
-	/* fall through */
+        if (!syncwrite) {
+            ioreq->presync = ioreq->postsync = 1;
+        }
+        /* fall through */
     case BLKIF_OP_WRITE:
-	ioreq->prot = PROT_READ; /* from memory */
-	if (syncwrite)
-	    ioreq->postsync = 1;
-	break;
+        ioreq->prot = PROT_READ; /* from memory */
+        if (syncwrite) {
+            ioreq->postsync = 1;
+        }
+        break;
     default:
-	xen_be_printf(&blkdev->xendev, 0, "error: unknown operation (%d)\n",
-		      ioreq->req.operation);
-	goto err;
+        xen_be_printf(&blkdev->xendev, 0, "error: unknown operation (%d)\n",
+                      ioreq->req.operation);
+        goto err;
     };
 
     if (ioreq->req.operation != BLKIF_OP_READ && blkdev->mode[0] != 'w') {
@@ -206,29 +209,29 @@ static int ioreq_parse(struct ioreq *ioreq)
 
     ioreq->start = ioreq->req.sector_number * blkdev->file_blk;
     for (i = 0; i < ioreq->req.nr_segments; i++) {
-	if (i == BLKIF_MAX_SEGMENTS_PER_REQUEST) {
-	    xen_be_printf(&blkdev->xendev, 0, "error: nr_segments too big\n");
-	    goto err;
-	}
-	if (ioreq->req.seg[i].first_sect > ioreq->req.seg[i].last_sect) {
-	    xen_be_printf(&blkdev->xendev, 0, "error: first > last sector\n");
-	    goto err;
-	}
-	if (ioreq->req.seg[i].last_sect * BLOCK_SIZE >= XC_PAGE_SIZE) {
-	    xen_be_printf(&blkdev->xendev, 0, "error: page crossing\n");
-	    goto err;
-	}
-
-	ioreq->domids[i] = blkdev->xendev.dom;
-	ioreq->refs[i]   = ioreq->req.seg[i].gref;
-
-	mem = ioreq->req.seg[i].first_sect * blkdev->file_blk;
-	len = (ioreq->req.seg[i].last_sect - ioreq->req.seg[i].first_sect + 1) * blkdev->file_blk;
+        if (i == BLKIF_MAX_SEGMENTS_PER_REQUEST) {
+            xen_be_printf(&blkdev->xendev, 0, "error: nr_segments too big\n");
+            goto err;
+        }
+        if (ioreq->req.seg[i].first_sect > ioreq->req.seg[i].last_sect) {
+            xen_be_printf(&blkdev->xendev, 0, "error: first > last sector\n");
+            goto err;
+        }
+        if (ioreq->req.seg[i].last_sect * BLOCK_SIZE >= XC_PAGE_SIZE) {
+            xen_be_printf(&blkdev->xendev, 0, "error: page crossing\n");
+            goto err;
+        }
+
+        ioreq->domids[i] = blkdev->xendev.dom;
+        ioreq->refs[i]   = ioreq->req.seg[i].gref;
+
+        mem = ioreq->req.seg[i].first_sect * blkdev->file_blk;
+        len = (ioreq->req.seg[i].last_sect - ioreq->req.seg[i].first_sect + 1) * blkdev->file_blk;
         qemu_iovec_add(&ioreq->v, (void*)mem, len);
     }
     if (ioreq->start + ioreq->v.size > blkdev->file_size) {
-	xen_be_printf(&blkdev->xendev, 0, "error: access beyond end of file\n");
-	goto err;
+        xen_be_printf(&blkdev->xendev, 0, "error: access beyond end of file\n");
+        goto err;
     }
     return 0;
 
@@ -239,66 +242,73 @@ err:
 
 static void ioreq_unmap(struct ioreq *ioreq)
 {
-    int gnt = ioreq->blkdev->xendev.gnttabdev;
+    XenGnttab gnt = ioreq->blkdev->xendev.gnttabdev;
     int i;
 
-    if (ioreq->v.niov == 0)
+    if (ioreq->v.niov == 0) {
         return;
+    }
     if (batch_maps) {
-	if (!ioreq->pages)
-	    return;
-	if (xc_gnttab_munmap(gnt, ioreq->pages, ioreq->v.niov) != 0)
-	    xen_be_printf(&ioreq->blkdev->xendev, 0, "xc_gnttab_munmap failed: %s\n",
-			  strerror(errno));
-	ioreq->blkdev->cnt_map -= ioreq->v.niov;
-	ioreq->pages = NULL;
+        if (!ioreq->pages) {
+            return;
+        }
+        if (xc_gnttab_munmap(gnt, ioreq->pages, ioreq->v.niov) != 0) {
+            xen_be_printf(&ioreq->blkdev->xendev, 0, "xc_gnttab_munmap failed: %s\n",
+                          strerror(errno));
+        }
+        ioreq->blkdev->cnt_map -= ioreq->v.niov;
+        ioreq->pages = NULL;
     } else {
-	for (i = 0; i < ioreq->v.niov; i++) {
-	    if (!ioreq->page[i])
-		continue;
-	    if (xc_gnttab_munmap(gnt, ioreq->page[i], 1) != 0)
-		xen_be_printf(&ioreq->blkdev->xendev, 0, "xc_gnttab_munmap failed: %s\n",
-			      strerror(errno));
-	    ioreq->blkdev->cnt_map--;
-	    ioreq->page[i] = NULL;
-	}
+        for (i = 0; i < ioreq->v.niov; i++) {
+            if (!ioreq->page[i]) {
+                continue;
+            }
+            if (xc_gnttab_munmap(gnt, ioreq->page[i], 1) != 0) {
+                xen_be_printf(&ioreq->blkdev->xendev, 0, "xc_gnttab_munmap failed: %s\n",
+                              strerror(errno));
+            }
+            ioreq->blkdev->cnt_map--;
+            ioreq->page[i] = NULL;
+        }
     }
 }
 
 static int ioreq_map(struct ioreq *ioreq)
 {
-    int gnt = ioreq->blkdev->xendev.gnttabdev;
+    XenGnttab gnt = ioreq->blkdev->xendev.gnttabdev;
     int i;
 
-    if (ioreq->v.niov == 0)
+    if (ioreq->v.niov == 0) {
         return 0;
+    }
     if (batch_maps) {
-	ioreq->pages = xc_gnttab_map_grant_refs
-	    (gnt, ioreq->v.niov, ioreq->domids, ioreq->refs, ioreq->prot);
-	if (ioreq->pages == NULL) {
-	    xen_be_printf(&ioreq->blkdev->xendev, 0,
-			  "can't map %d grant refs (%s, %d maps)\n",
-			  ioreq->v.niov, strerror(errno), ioreq->blkdev->cnt_map);
-	    return -1;
-	}
-	for (i = 0; i < ioreq->v.niov; i++)
-	    ioreq->v.iov[i].iov_base = ioreq->pages + i * XC_PAGE_SIZE +
-		(uintptr_t)ioreq->v.iov[i].iov_base;
-	ioreq->blkdev->cnt_map += ioreq->v.niov;
+        ioreq->pages = xc_gnttab_map_grant_refs
+            (gnt, ioreq->v.niov, ioreq->domids, ioreq->refs, ioreq->prot);
+        if (ioreq->pages == NULL) {
+            xen_be_printf(&ioreq->blkdev->xendev, 0,
+                          "can't map %d grant refs (%s, %d maps)\n",
+                          ioreq->v.niov, strerror(errno), ioreq->blkdev->cnt_map);
+            return -1;
+        }
+        for (i = 0; i < ioreq->v.niov; i++) {
+            ioreq->v.iov[i].iov_base = ioreq->pages + i * XC_PAGE_SIZE +
+                (uintptr_t)ioreq->v.iov[i].iov_base;
+        }
+        ioreq->blkdev->cnt_map += ioreq->v.niov;
     } else  {
-	for (i = 0; i < ioreq->v.niov; i++) {
-	    ioreq->page[i] = xc_gnttab_map_grant_ref
-		(gnt, ioreq->domids[i], ioreq->refs[i], ioreq->prot);
-	    if (ioreq->page[i] == NULL) {
-		xen_be_printf(&ioreq->blkdev->xendev, 0,
-			      "can't map grant ref %d (%s, %d maps)\n",
-			      ioreq->refs[i], strerror(errno), ioreq->blkdev->cnt_map);
-		ioreq_unmap(ioreq);
-		return -1;
-	    }
-	    ioreq->v.iov[i].iov_base = ioreq->page[i] + (uintptr_t)ioreq->v.iov[i].iov_base;
-	    ioreq->blkdev->cnt_map++;
-	}
+        for (i = 0; i < ioreq->v.niov; i++) {
+            ioreq->page[i] = xc_gnttab_map_grant_ref
+                (gnt, ioreq->domids[i], ioreq->refs[i], ioreq->prot);
+            if (ioreq->page[i] == NULL) {
+                xen_be_printf(&ioreq->blkdev->xendev, 0,
+                              "can't map grant ref %d (%s, %d maps)\n",
+                              ioreq->refs[i], strerror(errno), ioreq->blkdev->cnt_map);
+                ioreq_unmap(ioreq);
+                return -1;
+            }
+            ioreq->v.iov[i].iov_base = ioreq->page[i] + (uintptr_t)ioreq->v.iov[i].iov_base;
+            ioreq->blkdev->cnt_map++;
+        }
     }
     return 0;
 }
@@ -309,54 +319,58 @@ static int ioreq_runio_qemu_sync(struct ioreq *ioreq)
     int i, rc, len = 0;
     off_t pos;
 
-    if (ioreq->req.nr_segments && ioreq_map(ioreq) == -1)
-	goto err_no_map;
-    if (ioreq->presync)
-	bdrv_flush(blkdev->bs);
+    if (ioreq->req.nr_segments && ioreq_map(ioreq) == -1) {
+        goto err_no_map;
+    }
+    if (ioreq->presync) {
+        bdrv_flush(blkdev->bs);
+    }
 
     switch (ioreq->req.operation) {
     case BLKIF_OP_READ:
-	pos = ioreq->start;
-	for (i = 0; i < ioreq->v.niov; i++) {
-	    rc = bdrv_read(blkdev->bs, pos / BLOCK_SIZE,
-			   ioreq->v.iov[i].iov_base,
-			   ioreq->v.iov[i].iov_len / BLOCK_SIZE);
-	    if (rc != 0) {
-		xen_be_printf(&blkdev->xendev, 0, "rd I/O error (%p, len %zd)\n",
-			      ioreq->v.iov[i].iov_base,
-			      ioreq->v.iov[i].iov_len);
-		goto err;
-	    }
-	    len += ioreq->v.iov[i].iov_len;
-	    pos += ioreq->v.iov[i].iov_len;
-	}
-	break;
+        pos = ioreq->start;
+        for (i = 0; i < ioreq->v.niov; i++) {
+            rc = bdrv_read(blkdev->bs, pos / BLOCK_SIZE,
+                           ioreq->v.iov[i].iov_base,
+                           ioreq->v.iov[i].iov_len / BLOCK_SIZE);
+            if (rc != 0) {
+                xen_be_printf(&blkdev->xendev, 0, "rd I/O error (%p, len %zd)\n",
+                              ioreq->v.iov[i].iov_base,
+                              ioreq->v.iov[i].iov_len);
+                goto err;
+            }
+            len += ioreq->v.iov[i].iov_len;
+            pos += ioreq->v.iov[i].iov_len;
+        }
+        break;
     case BLKIF_OP_WRITE:
     case BLKIF_OP_WRITE_BARRIER:
-        if (!ioreq->req.nr_segments)
+        if (!ioreq->req.nr_segments) {
             break;
-	pos = ioreq->start;
-	for (i = 0; i < ioreq->v.niov; i++) {
-	    rc = bdrv_write(blkdev->bs, pos / BLOCK_SIZE,
-			    ioreq->v.iov[i].iov_base,
-			    ioreq->v.iov[i].iov_len / BLOCK_SIZE);
-	    if (rc != 0) {
-		xen_be_printf(&blkdev->xendev, 0, "wr I/O error (%p, len %zd)\n",
-			      ioreq->v.iov[i].iov_base,
-			      ioreq->v.iov[i].iov_len);
-		goto err;
-	    }
-	    len += ioreq->v.iov[i].iov_len;
-	    pos += ioreq->v.iov[i].iov_len;
-	}
-	break;
+        }
+        pos = ioreq->start;
+        for (i = 0; i < ioreq->v.niov; i++) {
+            rc = bdrv_write(blkdev->bs, pos / BLOCK_SIZE,
+                            ioreq->v.iov[i].iov_base,
+                            ioreq->v.iov[i].iov_len / BLOCK_SIZE);
+            if (rc != 0) {
+                xen_be_printf(&blkdev->xendev, 0, "wr I/O error (%p, len %zd)\n",
+                              ioreq->v.iov[i].iov_base,
+                              ioreq->v.iov[i].iov_len);
+                goto err;
+            }
+            len += ioreq->v.iov[i].iov_len;
+            pos += ioreq->v.iov[i].iov_len;
+        }
+        break;
     default:
-	/* unknown operation (shouldn't happen -- parse catches this) */
-	goto err;
+        /* unknown operation (shouldn't happen -- parse catches this) */
+        goto err;
     }
 
-    if (ioreq->postsync)
-	bdrv_flush(blkdev->bs);
+    if (ioreq->postsync) {
+        bdrv_flush(blkdev->bs);
+    }
     ioreq->status = BLKIF_RSP_OKAY;
 
     ioreq_unmap(ioreq);
@@ -382,8 +396,9 @@ static void qemu_aio_complete(void *opaque, int ret)
     }
 
     ioreq->aio_inflight--;
-    if (ioreq->aio_inflight > 0)
+    if (ioreq->aio_inflight > 0) {
         return;
+    }
 
     ioreq->status = ioreq->aio_errors ? BLKIF_RSP_ERROR : BLKIF_RSP_OKAY;
     ioreq_unmap(ioreq);
@@ -395,12 +410,14 @@ static int ioreq_runio_qemu_aio(struct ioreq *ioreq)
 {
     struct XenBlkDev *blkdev = ioreq->blkdev;
 
-    if (ioreq->req.nr_segments && ioreq_map(ioreq) == -1)
-	goto err_no_map;
+    if (ioreq->req.nr_segments && ioreq_map(ioreq) == -1) {
+        goto err_no_map;
+    }
 
     ioreq->aio_inflight++;
-    if (ioreq->presync)
-	bdrv_flush(blkdev->bs); /* FIXME: aio_flush() ??? */
+    if (ioreq->presync) {
+        bdrv_flush(blkdev->bs); /* FIXME: aio_flush() ??? */
+    }
 
     switch (ioreq->req.operation) {
     case BLKIF_OP_READ:
@@ -408,23 +425,25 @@ static int ioreq_runio_qemu_aio(struct ioreq *ioreq)
         bdrv_aio_readv(blkdev->bs, ioreq->start / BLOCK_SIZE,
                        &ioreq->v, ioreq->v.size / BLOCK_SIZE,
                        qemu_aio_complete, ioreq);
-	break;
+        break;
     case BLKIF_OP_WRITE:
     case BLKIF_OP_WRITE_BARRIER:
-        if (!ioreq->req.nr_segments)
+        if (!ioreq->req.nr_segments) {
             break;
+        }
         ioreq->aio_inflight++;
         bdrv_aio_writev(blkdev->bs, ioreq->start / BLOCK_SIZE,
                         &ioreq->v, ioreq->v.size / BLOCK_SIZE,
                         qemu_aio_complete, ioreq);
-	break;
+        break;
     default:
-	/* unknown operation (shouldn't happen -- parse catches this) */
-	goto err;
+        /* unknown operation (shouldn't happen -- parse catches this) */
+        goto err;
     }
 
-    if (ioreq->postsync)
-	bdrv_flush(blkdev->bs); /* FIXME: aio_flush() ??? */
+    if (ioreq->postsync) {
+        bdrv_flush(blkdev->bs); /* FIXME: aio_flush() ??? */
+    }
     qemu_aio_complete(ioreq, 0);
 
     return 0;
@@ -452,36 +471,37 @@ static int blk_send_response_one(struct ioreq *ioreq)
     /* Place on the response ring for the relevant domain. */
     switch (blkdev->protocol) {
     case BLKIF_PROTOCOL_NATIVE:
-	dst = RING_GET_RESPONSE(&blkdev->rings.native, blkdev->rings.native.rsp_prod_pvt);
-	break;
+        dst = RING_GET_RESPONSE(&blkdev->rings.native, blkdev->rings.native.rsp_prod_pvt);
+        break;
     case BLKIF_PROTOCOL_X86_32:
         dst = RING_GET_RESPONSE(&blkdev->rings.x86_32_part,
                                 blkdev->rings.x86_32_part.rsp_prod_pvt);
-	break;
+        break;
     case BLKIF_PROTOCOL_X86_64:
         dst = RING_GET_RESPONSE(&blkdev->rings.x86_64_part,
                                 blkdev->rings.x86_64_part.rsp_prod_pvt);
-	break;
+        break;
     default:
-	dst = NULL;
+        dst = NULL;
     }
     memcpy(dst, &resp, sizeof(resp));
     blkdev->rings.common.rsp_prod_pvt++;
 
     RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&blkdev->rings.common, send_notify);
     if (blkdev->rings.common.rsp_prod_pvt == blkdev->rings.common.req_cons) {
-	/*
-	 * Tail check for pending requests. Allows frontend to avoid
-	 * notifications if requests are already in flight (lower
-	 * overheads and promotes batching).
-	 */
-	RING_FINAL_CHECK_FOR_REQUESTS(&blkdev->rings.common, have_requests);
+        /*
+         * Tail check for pending requests. Allows frontend to avoid
+         * notifications if requests are already in flight (lower
+         * overheads and promotes batching).
+         */
+        RING_FINAL_CHECK_FOR_REQUESTS(&blkdev->rings.common, have_requests);
     } else if (RING_HAS_UNCONSUMED_REQUESTS(&blkdev->rings.common)) {
-	have_requests = 1;
+        have_requests = 1;
     }
 
-    if (have_requests)
-	blkdev->more_work++;
+    if (have_requests) {
+        blkdev->more_work++;
+    }
     return send_notify;
 }
 
@@ -493,28 +513,29 @@ static void blk_send_response_all(struct XenBlkDev *blkdev)
 
     while (!QLIST_EMPTY(&blkdev->finished)) {
         ioreq = QLIST_FIRST(&blkdev->finished);
-	send_notify += blk_send_response_one(ioreq);
-	ioreq_release(ioreq);
+        send_notify += blk_send_response_one(ioreq);
+        ioreq_release(ioreq);
+    }
+    if (send_notify) {
+        xen_be_send_notify(&blkdev->xendev);
     }
-    if (send_notify)
-	xen_be_send_notify(&blkdev->xendev);
 }
 
 static int blk_get_request(struct XenBlkDev *blkdev, struct ioreq *ioreq, RING_IDX rc)
 {
     switch (blkdev->protocol) {
     case BLKIF_PROTOCOL_NATIVE:
-	memcpy(&ioreq->req, RING_GET_REQUEST(&blkdev->rings.native, rc),
-	       sizeof(ioreq->req));
-	break;
+        memcpy(&ioreq->req, RING_GET_REQUEST(&blkdev->rings.native, rc),
+               sizeof(ioreq->req));
+        break;
     case BLKIF_PROTOCOL_X86_32:
         blkif_get_x86_32_req(&ioreq->req,
                              RING_GET_REQUEST(&blkdev->rings.x86_32_part, rc));
-	break;
+        break;
     case BLKIF_PROTOCOL_X86_64:
         blkif_get_x86_64_req(&ioreq->req,
                              RING_GET_REQUEST(&blkdev->rings.x86_64_part, rc));
-	break;
+        break;
     }
     return 0;
 }
@@ -530,12 +551,14 @@ static void blk_handle_requests(struct XenBlkDev *blkdev)
     rp = blkdev->rings.common.sring->req_prod;
     xen_rmb(); /* Ensure we see queued requests up to 'rp'. */
 
-    if (use_aio)
+    if (use_aio) {
         blk_send_response_all(blkdev);
+    }
     while (rc != rp) {
         /* pull request from ring */
-        if (RING_REQUEST_CONS_OVERFLOW(&blkdev->rings.common, rc))
+        if (RING_REQUEST_CONS_OVERFLOW(&blkdev->rings.common, rc)) {
             break;
+        }
         ioreq = ioreq_start(blkdev);
         if (ioreq == NULL) {
             blkdev->more_work++;
@@ -546,8 +569,9 @@ static void blk_handle_requests(struct XenBlkDev *blkdev)
 
         /* parse them */
         if (ioreq_parse(ioreq) != 0) {
-            if (blk_send_response_one(ioreq))
+            if (blk_send_response_one(ioreq)) {
                 xen_be_send_notify(&blkdev->xendev);
+            }
             ioreq_release(ioreq);
             continue;
         }
@@ -560,11 +584,13 @@ static void blk_handle_requests(struct XenBlkDev *blkdev)
             ioreq_runio_qemu_sync(ioreq);
         }
     }
-    if (!use_aio)
+    if (!use_aio) {
         blk_send_response_all(blkdev);
+    }
 
-    if (blkdev->more_work && blkdev->requests_inflight < max_requests)
+    if (blkdev->more_work && blkdev->requests_inflight < max_requests) {
         qemu_bh_schedule(blkdev->bh);
+    }
 }
 
 /* ------------------------------------------------------------- */
@@ -583,8 +609,9 @@ static void blk_alloc(struct XenDevice *xendev)
     QLIST_INIT(&blkdev->finished);
     QLIST_INIT(&blkdev->freelist);
     blkdev->bh = qemu_bh_new(blk_bh, blkdev);
-    if (xen_mode != XEN_EMULATE)
+    if (xen_mode != XEN_EMULATE) {
         batch_maps = 1;
+    }
 }
 
 static int blk_init(struct XenDevice *xendev)
@@ -595,44 +622,50 @@ static int blk_init(struct XenDevice *xendev)
 
     /* read xenstore entries */
     if (blkdev->params == NULL) {
-	blkdev->params = xenstore_read_be_str(&blkdev->xendev, "params");
+        blkdev->params = xenstore_read_be_str(&blkdev->xendev, "params");
         h = strchr(blkdev->params, ':');
-	if (h != NULL) {
-	    blkdev->fileproto = blkdev->params;
-	    blkdev->filename  = h+1;
-	    *h = 0;
-	} else {
-	    blkdev->fileproto = "<unset>";
-	    blkdev->filename  = blkdev->params;
-	}
-    }
-    if (blkdev->mode == NULL)
-	blkdev->mode = xenstore_read_be_str(&blkdev->xendev, "mode");
-    if (blkdev->type == NULL)
-	blkdev->type = xenstore_read_be_str(&blkdev->xendev, "type");
-    if (blkdev->dev == NULL)
-	blkdev->dev = xenstore_read_be_str(&blkdev->xendev, "dev");
-    if (blkdev->devtype == NULL)
-	blkdev->devtype = xenstore_read_be_str(&blkdev->xendev, "device-type");
+        if (h != NULL) {
+            blkdev->fileproto = blkdev->params;
+            blkdev->filename  = h+1;
+            *h = 0;
+        } else {
+            blkdev->fileproto = "<unset>";
+            blkdev->filename  = blkdev->params;
+        }
+    }
+    if (blkdev->mode == NULL) {
+        blkdev->mode = xenstore_read_be_str(&blkdev->xendev, "mode");
+    }
+    if (blkdev->type == NULL) {
+        blkdev->type = xenstore_read_be_str(&blkdev->xendev, "type");
+    }
+    if (blkdev->dev == NULL) {
+        blkdev->dev = xenstore_read_be_str(&blkdev->xendev, "dev");
+    }
+    if (blkdev->devtype == NULL) {
+        blkdev->devtype = xenstore_read_be_str(&blkdev->xendev, "device-type");
+    }
 
     /* do we have all we need? */
     if (blkdev->params == NULL ||
-	blkdev->mode == NULL   ||
-	blkdev->type == NULL   ||
-	blkdev->dev == NULL)
-	return -1;
+        blkdev->mode == NULL   ||
+        blkdev->type == NULL   ||
+        blkdev->dev == NULL) {
+        return -1;
+    }
 
     /* read-only ? */
     if (strcmp(blkdev->mode, "w") == 0) {
-	qflags = BDRV_O_RDWR;
+        qflags = BDRV_O_RDWR;
     } else {
-	qflags = 0;
-	info  |= VDISK_READONLY;
+        qflags = 0;
+        info  |= VDISK_READONLY;
     }
 
     /* cdrom ? */
-    if (blkdev->devtype && !strcmp(blkdev->devtype, "cdrom"))
-	info  |= VDISK_CDROM;
+    if (blkdev->devtype && !strcmp(blkdev->devtype, "cdrom")) {
+        info  |= VDISK_CDROM;
+    }
 
     /* init qemu block driver */
     index = (blkdev->xendev.dev - 202 * 256) / 16;
@@ -649,7 +682,7 @@ static int blk_init(struct XenDevice *xendev)
     } else {
         /* setup via qemu cmdline -> already setup for us */
         xen_be_printf(&blkdev->xendev, 2, "get configured bdrv (cmdline setup)\n");
-	blkdev->bs = blkdev->dinfo->bdrv;
+        blkdev->bs = blkdev->dinfo->bdrv;
     }
     blkdev->file_blk  = BLOCK_SIZE;
     blkdev->file_size = bdrv_getlength(blkdev->bs);
@@ -657,21 +690,21 @@ static int blk_init(struct XenDevice *xendev)
         xen_be_printf(&blkdev->xendev, 1, "bdrv_getlength: %d (%s) | drv %s\n",
                       (int)blkdev->file_size, strerror(-blkdev->file_size),
                       blkdev->bs->drv ? blkdev->bs->drv->format_name : "-");
-	blkdev->file_size = 0;
+        blkdev->file_size = 0;
     }
     have_barriers = blkdev->bs->drv && blkdev->bs->drv->bdrv_flush ? 1 : 0;
 
     xen_be_printf(xendev, 1, "type \"%s\", fileproto \"%s\", filename \"%s\","
-		  " size %" PRId64 " (%" PRId64 " MB)\n",
-		  blkdev->type, blkdev->fileproto, blkdev->filename,
-		  blkdev->file_size, blkdev->file_size >> 20);
+                  " size %" PRId64 " (%" PRId64 " MB)\n",
+                  blkdev->type, blkdev->fileproto, blkdev->filename,
+                  blkdev->file_size, blkdev->file_size >> 20);
 
     /* fill info */
     xenstore_write_be_int(&blkdev->xendev, "feature-barrier", have_barriers);
     xenstore_write_be_int(&blkdev->xendev, "info",            info);
     xenstore_write_be_int(&blkdev->xendev, "sector-size",     blkdev->file_blk);
     xenstore_write_be_int(&blkdev->xendev, "sectors",
-			  blkdev->file_size / blkdev->file_blk);
+                          blkdev->file_size / blkdev->file_blk);
     return 0;
 }
 
@@ -679,57 +712,62 @@ static int blk_connect(struct XenDevice *xendev)
 {
     struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
 
-    if (xenstore_read_fe_int(&blkdev->xendev, "ring-ref", &blkdev->ring_ref) == -1)
-	return -1;
+    if (xenstore_read_fe_int(&blkdev->xendev, "ring-ref", &blkdev->ring_ref) == -1) {
+        return -1;
+    }
     if (xenstore_read_fe_int(&blkdev->xendev, "event-channel",
-                             &blkdev->xendev.remote_port) == -1)
-	return -1;
+                             &blkdev->xendev.remote_port) == -1) {
+        return -1;
+    }
 
     blkdev->protocol = BLKIF_PROTOCOL_NATIVE;
     if (blkdev->xendev.protocol) {
-        if (strcmp(blkdev->xendev.protocol, XEN_IO_PROTO_ABI_X86_32) == 0)
+        if (strcmp(blkdev->xendev.protocol, XEN_IO_PROTO_ABI_X86_32) == 0) {
             blkdev->protocol = BLKIF_PROTOCOL_X86_32;
-        if (strcmp(blkdev->xendev.protocol, XEN_IO_PROTO_ABI_X86_64) == 0)
+        }
+        if (strcmp(blkdev->xendev.protocol, XEN_IO_PROTO_ABI_X86_64) == 0) {
             blkdev->protocol = BLKIF_PROTOCOL_X86_64;
+        }
     }
 
     blkdev->sring = xc_gnttab_map_grant_ref(blkdev->xendev.gnttabdev,
-					    blkdev->xendev.dom,
-					    blkdev->ring_ref,
-					    PROT_READ | PROT_WRITE);
-    if (!blkdev->sring)
-	return -1;
+                                            blkdev->xendev.dom,
+                                            blkdev->ring_ref,
+                                            PROT_READ | PROT_WRITE);
+    if (!blkdev->sring) {
+        return -1;
+    }
     blkdev->cnt_map++;
 
     switch (blkdev->protocol) {
     case BLKIF_PROTOCOL_NATIVE:
     {
-	blkif_sring_t *sring_native = blkdev->sring;
-	BACK_RING_INIT(&blkdev->rings.native, sring_native, XC_PAGE_SIZE);
-	break;
+        blkif_sring_t *sring_native = blkdev->sring;
+        BACK_RING_INIT(&blkdev->rings.native, sring_native, XC_PAGE_SIZE);
+        break;
     }
     case BLKIF_PROTOCOL_X86_32:
     {
-	blkif_x86_32_sring_t *sring_x86_32 = blkdev->sring;
+        blkif_x86_32_sring_t *sring_x86_32 = blkdev->sring;
 
         BACK_RING_INIT(&blkdev->rings.x86_32_part, sring_x86_32, XC_PAGE_SIZE);
-	break;
+        break;
     }
     case BLKIF_PROTOCOL_X86_64:
     {
-	blkif_x86_64_sring_t *sring_x86_64 = blkdev->sring;
+        blkif_x86_64_sring_t *sring_x86_64 = blkdev->sring;
 
         BACK_RING_INIT(&blkdev->rings.x86_64_part, sring_x86_64, XC_PAGE_SIZE);
-	break;
+        break;
     }
     }
 
     xen_be_bind_evtchn(&blkdev->xendev);
 
     xen_be_printf(&blkdev->xendev, 1, "ok: proto %s, ring-ref %d, "
-		  "remote port %d, local port %d\n",
-		  blkdev->xendev.protocol, blkdev->ring_ref,
-		  blkdev->xendev.remote_port, blkdev->xendev.local_port);
+                  "remote port %d, local port %d\n",
+                  blkdev->xendev.protocol, blkdev->ring_ref,
+                  blkdev->xendev.remote_port, blkdev->xendev.local_port);
     return 0;
 }
 
@@ -743,14 +781,14 @@ static void blk_disconnect(struct XenDevice *xendev)
             bdrv_close(blkdev->bs);
             bdrv_delete(blkdev->bs);
         }
-	blkdev->bs = NULL;
+        blkdev->bs = NULL;
     }
     xen_be_unbind_evtchn(&blkdev->xendev);
 
     if (blkdev->sring) {
-	xc_gnttab_munmap(blkdev->xendev.gnttabdev, blkdev->sring, 1);
-	blkdev->cnt_map--;
-	blkdev->sring = NULL;
+        xc_gnttab_munmap(blkdev->xendev.gnttabdev, blkdev->sring, 1);
+        blkdev->cnt_map--;
+        blkdev->sring = NULL;
     }
 }
 
@@ -760,10 +798,10 @@ static int blk_free(struct XenDevice *xendev)
     struct ioreq *ioreq;
 
     while (!QLIST_EMPTY(&blkdev->freelist)) {
-	ioreq = QLIST_FIRST(&blkdev->freelist);
+        ioreq = QLIST_FIRST(&blkdev->freelist);
         QLIST_REMOVE(ioreq, list);
         qemu_iovec_destroy(&ioreq->v);
-	qemu_free(ioreq);
+        qemu_free(ioreq);
     }
 
     qemu_free(blkdev->params);
diff --git a/hw/xen_domainbuild.c b/hw/xen_domainbuild.c
index 4093587df1..a6a12e5930 100644
--- a/hw/xen_domainbuild.c
+++ b/hw/xen_domainbuild.c
@@ -175,8 +175,9 @@ static int xen_domain_watcher(void)
     for (i = 3; i < n; i++) {
         if (i == fd[0])
             continue;
-        if (i == xen_xc)
+        if (i == xc_fd(xen_xc)) {
             continue;
+        }
         close(i);
     }
 
diff --git a/hw/xen_machine_pv.c b/hw/xen_machine_pv.c
index 0d7f73ed82..7985d11d5a 100644
--- a/hw/xen_machine_pv.c
+++ b/hw/xen_machine_pv.c
@@ -113,6 +113,7 @@ static QEMUMachine xenpv_machine = {
     .desc = "Xen Para-virtualized PC",
     .init = xen_init_pv,
     .max_cpus = 1,
+    .default_machine_opts = "accel=xen",
 };
 
 static void xenpv_machine_init(void)
diff --git a/hw/xen_nic.c b/hw/xen_nic.c
index 08055b83ff..ff86491cfa 100644
--- a/hw/xen_nic.c
+++ b/hw/xen_nic.c
@@ -74,20 +74,23 @@ static void net_tx_response(struct XenNetDev *netdev, netif_tx_request_t *txp, i
     resp->status = st;
 
 #if 0
-    if (txp->flags & NETTXF_extra_info)
-	RING_GET_RESPONSE(&netdev->tx_ring, ++i)->status = NETIF_RSP_NULL;
+    if (txp->flags & NETTXF_extra_info) {
+        RING_GET_RESPONSE(&netdev->tx_ring, ++i)->status = NETIF_RSP_NULL;
+    }
 #endif
 
     netdev->tx_ring.rsp_prod_pvt = ++i;
     RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&netdev->tx_ring, notify);
-    if (notify)
-	xen_be_send_notify(&netdev->xendev);
+    if (notify) {
+        xen_be_send_notify(&netdev->xendev);
+    }
 
     if (i == netdev->tx_ring.req_cons) {
-	int more_to_do;
-	RING_FINAL_CHECK_FOR_REQUESTS(&netdev->tx_ring, more_to_do);
-	if (more_to_do)
-	    netdev->tx_work++;
+        int more_to_do;
+        RING_FINAL_CHECK_FOR_REQUESTS(&netdev->tx_ring, more_to_do);
+        if (more_to_do) {
+            netdev->tx_work++;
+        }
     }
 }
 
@@ -101,10 +104,11 @@ static void net_tx_error(struct XenNetDev *netdev, netif_tx_request_t *txp, RING
     RING_IDX cons = netdev->tx_ring.req_cons;
 
     do {
-	make_tx_response(netif, txp, NETIF_RSP_ERROR);
-	if (cons >= end)
-	    break;
-	txp = RING_GET_REQUEST(&netdev->tx_ring, cons++);
+        make_tx_response(netif, txp, NETIF_RSP_ERROR);
+        if (cons >= end) {
+            break;
+        }
+        txp = RING_GET_REQUEST(&netdev->tx_ring, cons++);
     } while (1);
     netdev->tx_ring.req_cons = cons;
     netif_schedule_work(netif);
@@ -122,75 +126,78 @@ static void net_tx_packets(struct XenNetDev *netdev)
     void *tmpbuf = NULL;
 
     for (;;) {
-	rc = netdev->tx_ring.req_cons;
-	rp = netdev->tx_ring.sring->req_prod;
-	xen_rmb(); /* Ensure we see queued requests up to 'rp'. */
+        rc = netdev->tx_ring.req_cons;
+        rp = netdev->tx_ring.sring->req_prod;
+        xen_rmb(); /* Ensure we see queued requests up to 'rp'. */
 
-	while ((rc != rp)) {
-	    if (RING_REQUEST_CONS_OVERFLOW(&netdev->tx_ring, rc))
-		break;
-	    memcpy(&txreq, RING_GET_REQUEST(&netdev->tx_ring, rc), sizeof(txreq));
-	    netdev->tx_ring.req_cons = ++rc;
+        while ((rc != rp)) {
+            if (RING_REQUEST_CONS_OVERFLOW(&netdev->tx_ring, rc)) {
+                break;
+            }
+            memcpy(&txreq, RING_GET_REQUEST(&netdev->tx_ring, rc), sizeof(txreq));
+            netdev->tx_ring.req_cons = ++rc;
 
 #if 1
-	    /* should not happen in theory, we don't announce the *
-	     * feature-{sg,gso,whatelse} flags in xenstore (yet?) */
-	    if (txreq.flags & NETTXF_extra_info) {
-		xen_be_printf(&netdev->xendev, 0, "FIXME: extra info flag\n");
-		net_tx_error(netdev, &txreq, rc);
-		continue;
-	    }
-	    if (txreq.flags & NETTXF_more_data) {
-		xen_be_printf(&netdev->xendev, 0, "FIXME: more data flag\n");
-		net_tx_error(netdev, &txreq, rc);
-		continue;
-	    }
+            /* should not happen in theory, we don't announce the *
+             * feature-{sg,gso,whatelse} flags in xenstore (yet?) */
+            if (txreq.flags & NETTXF_extra_info) {
+                xen_be_printf(&netdev->xendev, 0, "FIXME: extra info flag\n");
+                net_tx_error(netdev, &txreq, rc);
+                continue;
+            }
+            if (txreq.flags & NETTXF_more_data) {
+                xen_be_printf(&netdev->xendev, 0, "FIXME: more data flag\n");
+                net_tx_error(netdev, &txreq, rc);
+                continue;
+            }
 #endif
 
-	    if (txreq.size < 14) {
-		xen_be_printf(&netdev->xendev, 0, "bad packet size: %d\n", txreq.size);
-		net_tx_error(netdev, &txreq, rc);
-		continue;
-	    }
-
-	    if ((txreq.offset + txreq.size) > XC_PAGE_SIZE) {
-		xen_be_printf(&netdev->xendev, 0, "error: page crossing\n");
-		net_tx_error(netdev, &txreq, rc);
-		continue;
-	    }
-
-	    xen_be_printf(&netdev->xendev, 3, "tx packet ref %d, off %d, len %d, flags 0x%x%s%s%s%s\n",
-			  txreq.gref, txreq.offset, txreq.size, txreq.flags,
-			  (txreq.flags & NETTXF_csum_blank)     ? " csum_blank"     : "",
-			  (txreq.flags & NETTXF_data_validated) ? " data_validated" : "",
-			  (txreq.flags & NETTXF_more_data)      ? " more_data"      : "",
-			  (txreq.flags & NETTXF_extra_info)     ? " extra_info"     : "");
-
-	    page = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev,
-					   netdev->xendev.dom,
-					   txreq.gref, PROT_READ);
-	    if (page == NULL) {
-		xen_be_printf(&netdev->xendev, 0, "error: tx gref dereference failed (%d)\n",
+            if (txreq.size < 14) {
+                xen_be_printf(&netdev->xendev, 0, "bad packet size: %d\n", txreq.size);
+                net_tx_error(netdev, &txreq, rc);
+                continue;
+            }
+
+            if ((txreq.offset + txreq.size) > XC_PAGE_SIZE) {
+                xen_be_printf(&netdev->xendev, 0, "error: page crossing\n");
+                net_tx_error(netdev, &txreq, rc);
+                continue;
+            }
+
+            xen_be_printf(&netdev->xendev, 3, "tx packet ref %d, off %d, len %d, flags 0x%x%s%s%s%s\n",
+                          txreq.gref, txreq.offset, txreq.size, txreq.flags,
+                          (txreq.flags & NETTXF_csum_blank)     ? " csum_blank"     : "",
+                          (txreq.flags & NETTXF_data_validated) ? " data_validated" : "",
+                          (txreq.flags & NETTXF_more_data)      ? " more_data"      : "",
+                          (txreq.flags & NETTXF_extra_info)     ? " extra_info"     : "");
+
+            page = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev,
+                                           netdev->xendev.dom,
+                                           txreq.gref, PROT_READ);
+            if (page == NULL) {
+                xen_be_printf(&netdev->xendev, 0, "error: tx gref dereference failed (%d)\n",
                               txreq.gref);
-		net_tx_error(netdev, &txreq, rc);
-		continue;
-	    }
-	    if (txreq.flags & NETTXF_csum_blank) {
+                net_tx_error(netdev, &txreq, rc);
+                continue;
+            }
+            if (txreq.flags & NETTXF_csum_blank) {
                 /* have read-only mapping -> can't fill checksum in-place */
-                if (!tmpbuf)
+                if (!tmpbuf) {
                     tmpbuf = qemu_malloc(XC_PAGE_SIZE);
+                }
                 memcpy(tmpbuf, page + txreq.offset, txreq.size);
-		net_checksum_calculate(tmpbuf, txreq.size);
+                net_checksum_calculate(tmpbuf, txreq.size);
                 qemu_send_packet(&netdev->nic->nc, tmpbuf, txreq.size);
             } else {
                 qemu_send_packet(&netdev->nic->nc, page + txreq.offset, txreq.size);
             }
-	    xc_gnttab_munmap(netdev->xendev.gnttabdev, page, 1);
-	    net_tx_response(netdev, &txreq, NETIF_RSP_OKAY);
-	}
-	if (!netdev->tx_work)
-	    break;
-	netdev->tx_work = 0;
+            xc_gnttab_munmap(netdev->xendev.gnttabdev, page, 1);
+            net_tx_response(netdev, &txreq, NETIF_RSP_OKAY);
+        }
+        if (!netdev->tx_work) {
+            break;
+        }
+        netdev->tx_work = 0;
     }
     qemu_free(tmpbuf);
 }
@@ -198,9 +205,9 @@ static void net_tx_packets(struct XenNetDev *netdev)
 /* ------------------------------------------------------------- */
 
 static void net_rx_response(struct XenNetDev *netdev,
-			    netif_rx_request_t *req, int8_t st,
-			    uint16_t offset, uint16_t size,
-			    uint16_t flags)
+                            netif_rx_request_t *req, int8_t st,
+                            uint16_t offset, uint16_t size,
+                            uint16_t flags)
 {
     RING_IDX i = netdev->rx_ring.rsp_prod_pvt;
     netif_rx_response_t *resp;
@@ -211,16 +218,18 @@ static void net_rx_response(struct XenNetDev *netdev,
     resp->flags      = flags;
     resp->id         = req->id;
     resp->status     = (int16_t)size;
-    if (st < 0)
-	resp->status = (int16_t)st;
+    if (st < 0) {
+        resp->status = (int16_t)st;
+    }
 
     xen_be_printf(&netdev->xendev, 3, "rx response: idx %d, status %d, flags 0x%x\n",
-		  i, resp->status, resp->flags);
+                  i, resp->status, resp->flags);
 
     netdev->rx_ring.rsp_prod_pvt = ++i;
     RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&netdev->rx_ring, notify);
-    if (notify)
-	xen_be_send_notify(&netdev->xendev);
+    if (notify) {
+        xen_be_send_notify(&netdev->xendev);
+    }
 }
 
 #define NET_IP_ALIGN 2
@@ -230,17 +239,18 @@ static int net_rx_ok(VLANClientState *nc)
     struct XenNetDev *netdev = DO_UPCAST(NICState, nc, nc)->opaque;
     RING_IDX rc, rp;
 
-    if (netdev->xendev.be_state != XenbusStateConnected)
-	return 0;
+    if (netdev->xendev.be_state != XenbusStateConnected) {
+        return 0;
+    }
 
     rc = netdev->rx_ring.req_cons;
     rp = netdev->rx_ring.sring->req_prod;
     xen_rmb();
 
     if (rc == rp || RING_REQUEST_CONS_OVERFLOW(&netdev->rx_ring, rc)) {
-	xen_be_printf(&netdev->xendev, 2, "%s: no rx buffers (%d/%d)\n",
-		      __FUNCTION__, rc, rp);
-	return 0;
+        xen_be_printf(&netdev->xendev, 2, "%s: no rx buffers (%d/%d)\n",
+                      __FUNCTION__, rc, rp);
+        return 0;
     }
     return 1;
 }
@@ -252,34 +262,35 @@ static ssize_t net_rx_packet(VLANClientState *nc, const uint8_t *buf, size_t siz
     RING_IDX rc, rp;
     void *page;
 
-    if (netdev->xendev.be_state != XenbusStateConnected)
-	return -1;
+    if (netdev->xendev.be_state != XenbusStateConnected) {
+        return -1;
+    }
 
     rc = netdev->rx_ring.req_cons;
     rp = netdev->rx_ring.sring->req_prod;
     xen_rmb(); /* Ensure we see queued requests up to 'rp'. */
 
     if (rc == rp || RING_REQUEST_CONS_OVERFLOW(&netdev->rx_ring, rc)) {
-	xen_be_printf(&netdev->xendev, 2, "no buffer, drop packet\n");
-	return -1;
+        xen_be_printf(&netdev->xendev, 2, "no buffer, drop packet\n");
+        return -1;
     }
     if (size > XC_PAGE_SIZE - NET_IP_ALIGN) {
-	xen_be_printf(&netdev->xendev, 0, "packet too big (%lu > %ld)",
-		      (unsigned long)size, XC_PAGE_SIZE - NET_IP_ALIGN);
-	return -1;
+        xen_be_printf(&netdev->xendev, 0, "packet too big (%lu > %ld)",
+                      (unsigned long)size, XC_PAGE_SIZE - NET_IP_ALIGN);
+        return -1;
     }
 
     memcpy(&rxreq, RING_GET_REQUEST(&netdev->rx_ring, rc), sizeof(rxreq));
     netdev->rx_ring.req_cons = ++rc;
 
     page = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev,
-				   netdev->xendev.dom,
-				   rxreq.gref, PROT_WRITE);
+                                   netdev->xendev.dom,
+                                   rxreq.gref, PROT_WRITE);
     if (page == NULL) {
-	xen_be_printf(&netdev->xendev, 0, "error: rx gref dereference failed (%d)\n",
+        xen_be_printf(&netdev->xendev, 0, "error: rx gref dereference failed (%d)\n",
                       rxreq.gref);
-	net_rx_response(netdev, &rxreq, NETIF_RSP_ERROR, 0, 0, 0);
-	return -1;
+        net_rx_response(netdev, &rxreq, NETIF_RSP_ERROR, 0, 0, 0);
+        return -1;
     }
     memcpy(page + NET_IP_ALIGN, buf, size);
     xc_gnttab_munmap(netdev->xendev.gnttabdev, page, 1);
@@ -302,15 +313,18 @@ static int net_init(struct XenDevice *xendev)
     struct XenNetDev *netdev = container_of(xendev, struct XenNetDev, xendev);
 
     /* read xenstore entries */
-    if (netdev->mac == NULL)
-	netdev->mac = xenstore_read_be_str(&netdev->xendev, "mac");
+    if (netdev->mac == NULL) {
+        netdev->mac = xenstore_read_be_str(&netdev->xendev, "mac");
+    }
 
     /* do we have all we need? */
-    if (netdev->mac == NULL)
-	return -1;
+    if (netdev->mac == NULL) {
+        return -1;
+    }
 
-    if (net_parse_macaddr(netdev->conf.macaddr.a, netdev->mac) < 0)
+    if (net_parse_macaddr(netdev->conf.macaddr.a, netdev->mac) < 0) {
         return -1;
+    }
 
     netdev->conf.vlan = qemu_find_vlan(netdev->xendev.dev, 1);
     netdev->conf.peer = NULL;
@@ -334,41 +348,46 @@ static int net_connect(struct XenDevice *xendev)
     int rx_copy;
 
     if (xenstore_read_fe_int(&netdev->xendev, "tx-ring-ref",
-				   &netdev->tx_ring_ref) == -1)
-	return -1;
+                             &netdev->tx_ring_ref) == -1) {
+        return -1;
+    }
     if (xenstore_read_fe_int(&netdev->xendev, "rx-ring-ref",
-				   &netdev->rx_ring_ref) == -1)
-	return 1;
+                             &netdev->rx_ring_ref) == -1) {
+        return 1;
+    }
     if (xenstore_read_fe_int(&netdev->xendev, "event-channel",
-				   &netdev->xendev.remote_port) == -1)
-	return -1;
+                             &netdev->xendev.remote_port) == -1) {
+        return -1;
+    }
 
-    if (xenstore_read_fe_int(&netdev->xendev, "request-rx-copy", &rx_copy) == -1)
-	rx_copy = 0;
+    if (xenstore_read_fe_int(&netdev->xendev, "request-rx-copy", &rx_copy) == -1) {
+        rx_copy = 0;
+    }
     if (rx_copy == 0) {
-	xen_be_printf(&netdev->xendev, 0, "frontend doesn't support rx-copy.\n");
-	return -1;
+        xen_be_printf(&netdev->xendev, 0, "frontend doesn't support rx-copy.\n");
+        return -1;
     }
 
     netdev->txs = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev,
-					  netdev->xendev.dom,
-					  netdev->tx_ring_ref,
-					  PROT_READ | PROT_WRITE);
+                                          netdev->xendev.dom,
+                                          netdev->tx_ring_ref,
+                                          PROT_READ | PROT_WRITE);
     netdev->rxs = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev,
-					  netdev->xendev.dom,
-					  netdev->rx_ring_ref,
-					  PROT_READ | PROT_WRITE);
-    if (!netdev->txs || !netdev->rxs)
-	return -1;
+                                          netdev->xendev.dom,
+                                          netdev->rx_ring_ref,
+                                          PROT_READ | PROT_WRITE);
+    if (!netdev->txs || !netdev->rxs) {
+        return -1;
+    }
     BACK_RING_INIT(&netdev->tx_ring, netdev->txs, XC_PAGE_SIZE);
     BACK_RING_INIT(&netdev->rx_ring, netdev->rxs, XC_PAGE_SIZE);
 
     xen_be_bind_evtchn(&netdev->xendev);
 
     xen_be_printf(&netdev->xendev, 1, "ok: tx-ring-ref %d, rx-ring-ref %d, "
-		  "remote port %d, local port %d\n",
-		  netdev->tx_ring_ref, netdev->rx_ring_ref,
-		  netdev->xendev.remote_port, netdev->xendev.local_port);
+                  "remote port %d, local port %d\n",
+                  netdev->tx_ring_ref, netdev->rx_ring_ref,
+                  netdev->xendev.remote_port, netdev->xendev.local_port);
 
     net_tx_packets(netdev);
     return 0;
@@ -381,12 +400,12 @@ static void net_disconnect(struct XenDevice *xendev)
     xen_be_unbind_evtchn(&netdev->xendev);
 
     if (netdev->txs) {
-	xc_gnttab_munmap(netdev->xendev.gnttabdev, netdev->txs, 1);
-	netdev->txs = NULL;
+        xc_gnttab_munmap(netdev->xendev.gnttabdev, netdev->txs, 1);
+        netdev->txs = NULL;
     }
     if (netdev->rxs) {
-	xc_gnttab_munmap(netdev->xendev.gnttabdev, netdev->rxs, 1);
-	netdev->rxs = NULL;
+        xc_gnttab_munmap(netdev->xendev.gnttabdev, netdev->rxs, 1);
+        netdev->rxs = NULL;
     }
     if (netdev->nic) {
         qemu_del_vlan_client(&netdev->nic->nc);
diff --git a/qemu-config.c b/qemu-config.c
index 14d34194d0..5d7ffa2f23 100644
--- a/qemu-config.c
+++ b/qemu-config.c
@@ -450,6 +450,19 @@ QemuOptsList qemu_option_rom_opts = {
     },
 };
 
+static QemuOptsList qemu_machine_opts = {
+    .name = "machine",
+    .head = QTAILQ_HEAD_INITIALIZER(qemu_machine_opts.head),
+    .desc = {
+        {
+            .name = "accel",
+            .type = QEMU_OPT_STRING,
+            .help = "accelerator list",
+        },
+        { /* End of list */ }
+    },
+};
+
 static QemuOptsList *vm_config_groups[32] = {
     &qemu_drive_opts,
     &qemu_chardev_opts,
@@ -464,6 +477,7 @@ static QemuOptsList *vm_config_groups[32] = {
     &qemu_trace_opts,
 #endif
     &qemu_option_rom_opts,
+    &qemu_machine_opts,
     NULL,
 };
 
diff --git a/qemu-options.hx b/qemu-options.hx
index 489df10c46..9f121adcdb 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -2030,6 +2030,16 @@ Enable KVM full virtualization support. This option is only available
 if KVM support is enabled when compiling.
 ETEXI
 
+DEF("machine", HAS_ARG, QEMU_OPTION_machine, \
+    "-machine accel=accel1[:accel2]    use an accelerator (kvm,xen,tcg), default is tcg\n", QEMU_ARCH_ALL)
+STEXI
+@item -machine accel=@var{accels}
+@findex -machine
+This is use to enable an accelerator, in kvm,xen,tcg.
+By default, it use only tcg. If there a more than one accelerator
+specified, the next one is used if the first don't work.
+ETEXI
+
 DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid,
     "-xen-domid id   specify xen guest domain id\n", QEMU_ARCH_ALL)
 DEF("xen-create", 0, QEMU_OPTION_xen_create,
diff --git a/sysemu.h b/sysemu.h
index b0296a0d46..7e70daa3da 100644
--- a/sysemu.h
+++ b/sysemu.h
@@ -42,6 +42,8 @@ void qemu_system_shutdown_request(void);
 void qemu_system_powerdown_request(void);
 void qemu_system_debug_request(void);
 void qemu_system_vmstop_request(int reason);
+int qemu_shutdown_requested_get(void);
+int qemu_reset_requested_get(void);
 int qemu_shutdown_requested(void);
 int qemu_reset_requested(void);
 int qemu_powerdown_requested(void);
diff --git a/trace-events b/trace-events
index 4f965e2ebd..a00b63cefd 100644
--- a/trace-events
+++ b/trace-events
@@ -361,3 +361,16 @@ disable milkymist_uart_pulse_irq_tx(void) "Pulse IRQ TX"
 # hw/milkymist-vgafb.c
 disable milkymist_vgafb_memory_read(uint32_t addr, uint32_t value) "addr %08x value %08x"
 disable milkymist_vgafb_memory_write(uint32_t addr, uint32_t value) "addr %08x value %08x"
+
+# xen-all.c
+disable xen_ram_alloc(unsigned long ram_addr, unsigned long size) "requested: %#lx, size %#lx"
+
+# xen-mapcache.c
+disable qemu_map_cache(uint64_t phys_addr) "want %#"PRIx64""
+disable qemu_remap_bucket(uint64_t index) "index %#"PRIx64""
+disable qemu_map_cache_return(void* ptr) "%p"
+disable xen_map_block(uint64_t phys_addr, uint64_t size) "%#"PRIx64", size %#"PRIx64""
+disable xen_unmap_block(void* addr, unsigned long size) "%p, size %#lx"
+
+# exec.c
+disable qemu_put_ram_ptr(void* addr) "%p"
diff --git a/vl.c b/vl.c
index 6b9a2f61e3..bffba69408 100644
--- a/vl.c
+++ b/vl.c
@@ -257,7 +257,9 @@ static NotifierList exit_notifiers =
 static NotifierList machine_init_done_notifiers =
     NOTIFIER_LIST_INITIALIZER(machine_init_done_notifiers);
 
+static int tcg_allowed = 1;
 int kvm_allowed = 0;
+int xen_allowed = 0;
 uint32_t xen_domid;
 enum xen_mode xen_mode = XEN_EMULATE;
 
@@ -1159,6 +1161,16 @@ static int powerdown_requested;
 static int debug_requested;
 static int vmstop_requested;
 
+int qemu_shutdown_requested_get(void)
+{
+    return shutdown_requested;
+}
+
+int qemu_reset_requested_get(void)
+{
+    return reset_requested;
+}
+
 int qemu_shutdown_requested(void)
 {
     int r = shutdown_requested;
@@ -1876,6 +1888,83 @@ static int debugcon_parse(const char *devname)
     return 0;
 }
 
+static int tcg_init(void)
+{
+    return 0;
+}
+
+static struct {
+    const char *opt_name;
+    const char *name;
+    int (*available)(void);
+    int (*init)(void);
+    int *allowed;
+} accel_list[] = {
+    { "tcg", "tcg", tcg_available, tcg_init, &tcg_allowed },
+    { "xen", "Xen", xen_available, xen_init, &xen_allowed },
+    { "kvm", "KVM", kvm_available, kvm_init, &kvm_allowed },
+};
+
+static int configure_accelerator(void)
+{
+    const char *p = NULL;
+    char buf[10];
+    int i, ret;
+    bool accel_initalised = 0;
+    bool init_failed = 0;
+
+    QemuOptsList *list = qemu_find_opts("machine");
+    if (!QTAILQ_EMPTY(&list->head)) {
+        p = qemu_opt_get(QTAILQ_FIRST(&list->head), "accel");
+    }
+
+    if (p == NULL) {
+        /* Use the default "accelerator", tcg */
+        p = "tcg";
+    }
+
+    while (!accel_initalised && *p != '\0') {
+        if (*p == ':') {
+            p++;
+        }
+        p = get_opt_name(buf, sizeof (buf), p, ':');
+        for (i = 0; i < ARRAY_SIZE(accel_list); i++) {
+            if (strcmp(accel_list[i].opt_name, buf) == 0) {
+                ret = accel_list[i].init();
+                if (ret < 0) {
+                    init_failed = 1;
+                    if (!accel_list[i].available()) {
+                        printf("%s not supported for this target\n",
+                               accel_list[i].name);
+                    } else {
+                        fprintf(stderr, "failed to initialize %s: %s\n",
+                                accel_list[i].name,
+                                strerror(-ret));
+                    }
+                } else {
+                    accel_initalised = 1;
+                    *(accel_list[i].allowed) = 1;
+                }
+                break;
+            }
+        }
+        if (i == ARRAY_SIZE(accel_list)) {
+            fprintf(stderr, "\"%s\" accelerator does not exist.\n", buf);
+        }
+    }
+
+    if (!accel_initalised) {
+        fprintf(stderr, "No accelerator found!\n");
+        exit(1);
+    }
+
+    if (init_failed) {
+        fprintf(stderr, "Back to %s accelerator.\n", accel_list[i].name);
+    }
+
+    return !accel_initalised;
+}
+
 void qemu_add_exit_notifier(Notifier *notify)
 {
     notifier_list_add(&exit_notifiers, notify);
@@ -2576,7 +2665,18 @@ int main(int argc, char **argv, char **envp)
                 do_smbios_option(optarg);
                 break;
             case QEMU_OPTION_enable_kvm:
-                kvm_allowed = 1;
+                olist = qemu_find_opts("machine");
+                qemu_opts_reset(olist);
+                qemu_opts_parse(olist, "accel=kvm", 0);
+                break;
+            case QEMU_OPTION_machine:
+                olist = qemu_find_opts("machine");
+                qemu_opts_reset(olist);
+                opts = qemu_opts_parse(olist, optarg, 0);
+                if (!opts) {
+                    fprintf(stderr, "parse error: %s\n", optarg);
+                    exit(1);
+                }
                 break;
             case QEMU_OPTION_usb:
                 usb_enabled = 1;
@@ -2826,6 +2926,28 @@ int main(int argc, char **argv, char **envp)
         exit(1);
     }
 
+    /*
+     * Get the default machine options from the machine if it is not already
+     * specified either by the configuration file or by the command line.
+     */
+    if (machine->default_machine_opts) {
+        QemuOptsList *list = qemu_find_opts("machine");
+        const char *p = NULL;
+
+        if (!QTAILQ_EMPTY(&list->head)) {
+            p = qemu_opt_get(QTAILQ_FIRST(&list->head), "accel");
+        }
+        if (p == NULL) {
+            opts = qemu_opts_parse(qemu_find_opts("machine"),
+                                   machine->default_machine_opts, 0);
+            if (!opts) {
+                fprintf(stderr, "parse error for machine %s: %s\n",
+                        machine->name, machine->default_machine_opts);
+                exit(1);
+            }
+        }
+    }
+
     qemu_opts_foreach(qemu_find_opts("device"), default_driver_check, NULL, 0);
     qemu_opts_foreach(qemu_find_opts("global"), default_driver_check, NULL, 0);
 
@@ -2896,17 +3018,7 @@ int main(int argc, char **argv, char **envp)
         exit(1);
     }
 
-    if (kvm_allowed) {
-        int ret = kvm_init();
-        if (ret < 0) {
-            if (!kvm_available()) {
-                printf("KVM not supported for this target\n");
-            } else {
-                fprintf(stderr, "failed to initialize KVM: %s\n", strerror(-ret));
-            }
-            exit(1);
-        }
-    }
+    configure_accelerator();
 
     if (qemu_init_main_loop()) {
         fprintf(stderr, "qemu_init_main_loop failed\n");
diff --git a/xen-all.c b/xen-all.c
new file mode 100644
index 0000000000..0eac202d4e
--- /dev/null
+++ b/xen-all.c
@@ -0,0 +1,605 @@
+/*
+ * Copyright (C) 2010       Citrix Ltd.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.  See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+#include <sys/mman.h>
+
+#include "hw/pci.h"
+#include "hw/pc.h"
+#include "hw/xen_common.h"
+#include "hw/xen_backend.h"
+
+#include "xen-mapcache.h"
+#include "trace.h"
+
+#include <xen/hvm/ioreq.h>
+#include <xen/hvm/params.h>
+
+//#define DEBUG_XEN
+
+#ifdef DEBUG_XEN
+#define DPRINTF(fmt, ...) \
+    do { fprintf(stderr, "xen: " fmt, ## __VA_ARGS__); } while (0)
+#else
+#define DPRINTF(fmt, ...) \
+    do { } while (0)
+#endif
+
+/* Compatibility with older version */
+#if __XEN_LATEST_INTERFACE_VERSION__ < 0x0003020a
+static inline uint32_t xen_vcpu_eport(shared_iopage_t *shared_page, int i)
+{
+    return shared_page->vcpu_iodata[i].vp_eport;
+}
+static inline ioreq_t *xen_vcpu_ioreq(shared_iopage_t *shared_page, int vcpu)
+{
+    return &shared_page->vcpu_iodata[vcpu].vp_ioreq;
+}
+#  define FMT_ioreq_size PRIx64
+#else
+static inline uint32_t xen_vcpu_eport(shared_iopage_t *shared_page, int i)
+{
+    return shared_page->vcpu_ioreq[i].vp_eport;
+}
+static inline ioreq_t *xen_vcpu_ioreq(shared_iopage_t *shared_page, int vcpu)
+{
+    return &shared_page->vcpu_ioreq[vcpu];
+}
+#  define FMT_ioreq_size "u"
+#endif
+
+#define BUFFER_IO_MAX_DELAY  100
+
+typedef struct XenIOState {
+    shared_iopage_t *shared_page;
+    buffered_iopage_t *buffered_io_page;
+    QEMUTimer *buffered_io_timer;
+    /* the evtchn port for polling the notification, */
+    evtchn_port_t *ioreq_local_port;
+    /* the evtchn fd for polling */
+    XenEvtchn xce_handle;
+    /* which vcpu we are serving */
+    int send_vcpu;
+
+    struct xs_handle *xenstore;
+
+    Notifier exit;
+} XenIOState;
+
+/* Xen specific function for piix pci */
+
+int xen_pci_slot_get_pirq(PCIDevice *pci_dev, int irq_num)
+{
+    return irq_num + ((pci_dev->devfn >> 3) << 2);
+}
+
+void xen_piix3_set_irq(void *opaque, int irq_num, int level)
+{
+    xc_hvm_set_pci_intx_level(xen_xc, xen_domid, 0, 0, irq_num >> 2,
+                              irq_num & 3, level);
+}
+
+void xen_piix_pci_write_config_client(uint32_t address, uint32_t val, int len)
+{
+    int i;
+
+    /* Scan for updates to PCI link routes (0x60-0x63). */
+    for (i = 0; i < len; i++) {
+        uint8_t v = (val >> (8 * i)) & 0xff;
+        if (v & 0x80) {
+            v = 0;
+        }
+        v &= 0xf;
+        if (((address + i) >= 0x60) && ((address + i) <= 0x63)) {
+            xc_hvm_set_pci_link_route(xen_xc, xen_domid, address + i - 0x60, v);
+        }
+    }
+}
+
+void xen_cmos_set_s3_resume(void *opaque, int irq, int level)
+{
+    pc_cmos_set_s3_resume(opaque, irq, level);
+    if (level) {
+        xc_set_hvm_param(xen_xc, xen_domid, HVM_PARAM_ACPI_S_STATE, 3);
+    }
+}
+
+/* Xen Interrupt Controller */
+
+static void xen_set_irq(void *opaque, int irq, int level)
+{
+    xc_hvm_set_isa_irq_level(xen_xc, xen_domid, irq, level);
+}
+
+qemu_irq *xen_interrupt_controller_init(void)
+{
+    return qemu_allocate_irqs(xen_set_irq, NULL, 16);
+}
+
+/* Memory Ops */
+
+static void xen_ram_init(ram_addr_t ram_size)
+{
+    RAMBlock *new_block;
+    ram_addr_t below_4g_mem_size, above_4g_mem_size = 0;
+
+    new_block = qemu_mallocz(sizeof (*new_block));
+    pstrcpy(new_block->idstr, sizeof (new_block->idstr), "xen.ram");
+    new_block->host = NULL;
+    new_block->offset = 0;
+    new_block->length = ram_size;
+
+    QLIST_INSERT_HEAD(&ram_list.blocks, new_block, next);
+
+    ram_list.phys_dirty = qemu_realloc(ram_list.phys_dirty,
+                                       new_block->length >> TARGET_PAGE_BITS);
+    memset(ram_list.phys_dirty + (new_block->offset >> TARGET_PAGE_BITS),
+           0xff, new_block->length >> TARGET_PAGE_BITS);
+
+    if (ram_size >= 0xe0000000 ) {
+        above_4g_mem_size = ram_size - 0xe0000000;
+        below_4g_mem_size = 0xe0000000;
+    } else {
+        below_4g_mem_size = ram_size;
+    }
+
+    cpu_register_physical_memory(0, below_4g_mem_size, new_block->offset);
+#if TARGET_PHYS_ADDR_BITS > 32
+    if (above_4g_mem_size > 0) {
+        cpu_register_physical_memory(0x100000000ULL, above_4g_mem_size,
+                                     new_block->offset + below_4g_mem_size);
+    }
+#endif
+}
+
+void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size)
+{
+    unsigned long nr_pfn;
+    xen_pfn_t *pfn_list;
+    int i;
+
+    trace_xen_ram_alloc(ram_addr, size);
+
+    nr_pfn = size >> TARGET_PAGE_BITS;
+    pfn_list = qemu_malloc(sizeof (*pfn_list) * nr_pfn);
+
+    for (i = 0; i < nr_pfn; i++) {
+        pfn_list[i] = (ram_addr >> TARGET_PAGE_BITS) + i;
+    }
+
+    if (xc_domain_populate_physmap_exact(xen_xc, xen_domid, nr_pfn, 0, 0, pfn_list)) {
+        hw_error("xen: failed to populate ram at %lx", ram_addr);
+    }
+
+    qemu_free(pfn_list);
+}
+
+
+/* VCPU Operations, MMIO, IO ring ... */
+
+static void xen_reset_vcpu(void *opaque)
+{
+    CPUState *env = opaque;
+
+    env->halted = 1;
+}
+
+void xen_vcpu_init(void)
+{
+    CPUState *first_cpu;
+
+    if ((first_cpu = qemu_get_cpu(0))) {
+        qemu_register_reset(xen_reset_vcpu, first_cpu);
+        xen_reset_vcpu(first_cpu);
+    }
+}
+
+/* get the ioreq packets from share mem */
+static ioreq_t *cpu_get_ioreq_from_shared_memory(XenIOState *state, int vcpu)
+{
+    ioreq_t *req = xen_vcpu_ioreq(state->shared_page, vcpu);
+
+    if (req->state != STATE_IOREQ_READY) {
+        DPRINTF("I/O request not ready: "
+                "%x, ptr: %x, port: %"PRIx64", "
+                "data: %"PRIx64", count: %" FMT_ioreq_size ", size: %" FMT_ioreq_size "\n",
+                req->state, req->data_is_ptr, req->addr,
+                req->data, req->count, req->size);
+        return NULL;
+    }
+
+    xen_rmb(); /* see IOREQ_READY /then/ read contents of ioreq */
+
+    req->state = STATE_IOREQ_INPROCESS;
+    return req;
+}
+
+/* use poll to get the port notification */
+/* ioreq_vec--out,the */
+/* retval--the number of ioreq packet */
+static ioreq_t *cpu_get_ioreq(XenIOState *state)
+{
+    int i;
+    evtchn_port_t port;
+
+    port = xc_evtchn_pending(state->xce_handle);
+    if (port != -1) {
+        for (i = 0; i < smp_cpus; i++) {
+            if (state->ioreq_local_port[i] == port) {
+                break;
+            }
+        }
+
+        if (i == smp_cpus) {
+            hw_error("Fatal error while trying to get io event!\n");
+        }
+
+        /* unmask the wanted port again */
+        xc_evtchn_unmask(state->xce_handle, port);
+
+        /* get the io packet from shared memory */
+        state->send_vcpu = i;
+        return cpu_get_ioreq_from_shared_memory(state, i);
+    }
+
+    /* read error or read nothing */
+    return NULL;
+}
+
+static uint32_t do_inp(pio_addr_t addr, unsigned long size)
+{
+    switch (size) {
+        case 1:
+            return cpu_inb(addr);
+        case 2:
+            return cpu_inw(addr);
+        case 4:
+            return cpu_inl(addr);
+        default:
+            hw_error("inp: bad size: %04"FMT_pioaddr" %lx", addr, size);
+    }
+}
+
+static void do_outp(pio_addr_t addr,
+        unsigned long size, uint32_t val)
+{
+    switch (size) {
+        case 1:
+            return cpu_outb(addr, val);
+        case 2:
+            return cpu_outw(addr, val);
+        case 4:
+            return cpu_outl(addr, val);
+        default:
+            hw_error("outp: bad size: %04"FMT_pioaddr" %lx", addr, size);
+    }
+}
+
+static void cpu_ioreq_pio(ioreq_t *req)
+{
+    int i, sign;
+
+    sign = req->df ? -1 : 1;
+
+    if (req->dir == IOREQ_READ) {
+        if (!req->data_is_ptr) {
+            req->data = do_inp(req->addr, req->size);
+        } else {
+            uint32_t tmp;
+
+            for (i = 0; i < req->count; i++) {
+                tmp = do_inp(req->addr, req->size);
+                cpu_physical_memory_write(req->data + (sign * i * req->size),
+                        (uint8_t *) &tmp, req->size);
+            }
+        }
+    } else if (req->dir == IOREQ_WRITE) {
+        if (!req->data_is_ptr) {
+            do_outp(req->addr, req->size, req->data);
+        } else {
+            for (i = 0; i < req->count; i++) {
+                uint32_t tmp = 0;
+
+                cpu_physical_memory_read(req->data + (sign * i * req->size),
+                        (uint8_t*) &tmp, req->size);
+                do_outp(req->addr, req->size, tmp);
+            }
+        }
+    }
+}
+
+static void cpu_ioreq_move(ioreq_t *req)
+{
+    int i, sign;
+
+    sign = req->df ? -1 : 1;
+
+    if (!req->data_is_ptr) {
+        if (req->dir == IOREQ_READ) {
+            for (i = 0; i < req->count; i++) {
+                cpu_physical_memory_read(req->addr + (sign * i * req->size),
+                        (uint8_t *) &req->data, req->size);
+            }
+        } else if (req->dir == IOREQ_WRITE) {
+            for (i = 0; i < req->count; i++) {
+                cpu_physical_memory_write(req->addr + (sign * i * req->size),
+                        (uint8_t *) &req->data, req->size);
+            }
+        }
+    } else {
+        target_ulong tmp;
+
+        if (req->dir == IOREQ_READ) {
+            for (i = 0; i < req->count; i++) {
+                cpu_physical_memory_read(req->addr + (sign * i * req->size),
+                        (uint8_t*) &tmp, req->size);
+                cpu_physical_memory_write(req->data + (sign * i * req->size),
+                        (uint8_t*) &tmp, req->size);
+            }
+        } else if (req->dir == IOREQ_WRITE) {
+            for (i = 0; i < req->count; i++) {
+                cpu_physical_memory_read(req->data + (sign * i * req->size),
+                        (uint8_t*) &tmp, req->size);
+                cpu_physical_memory_write(req->addr + (sign * i * req->size),
+                        (uint8_t*) &tmp, req->size);
+            }
+        }
+    }
+}
+
+static void handle_ioreq(ioreq_t *req)
+{
+    if (!req->data_is_ptr && (req->dir == IOREQ_WRITE) &&
+            (req->size < sizeof (target_ulong))) {
+        req->data &= ((target_ulong) 1 << (8 * req->size)) - 1;
+    }
+
+    switch (req->type) {
+        case IOREQ_TYPE_PIO:
+            cpu_ioreq_pio(req);
+            break;
+        case IOREQ_TYPE_COPY:
+            cpu_ioreq_move(req);
+            break;
+        case IOREQ_TYPE_TIMEOFFSET:
+            break;
+        case IOREQ_TYPE_INVALIDATE:
+            qemu_invalidate_map_cache();
+            break;
+        default:
+            hw_error("Invalid ioreq type 0x%x\n", req->type);
+    }
+}
+
+static void handle_buffered_iopage(XenIOState *state)
+{
+    buf_ioreq_t *buf_req = NULL;
+    ioreq_t req;
+    int qw;
+
+    if (!state->buffered_io_page) {
+        return;
+    }
+
+    while (state->buffered_io_page->read_pointer != state->buffered_io_page->write_pointer) {
+        buf_req = &state->buffered_io_page->buf_ioreq[
+            state->buffered_io_page->read_pointer % IOREQ_BUFFER_SLOT_NUM];
+        req.size = 1UL << buf_req->size;
+        req.count = 1;
+        req.addr = buf_req->addr;
+        req.data = buf_req->data;
+        req.state = STATE_IOREQ_READY;
+        req.dir = buf_req->dir;
+        req.df = 1;
+        req.type = buf_req->type;
+        req.data_is_ptr = 0;
+        qw = (req.size == 8);
+        if (qw) {
+            buf_req = &state->buffered_io_page->buf_ioreq[
+                (state->buffered_io_page->read_pointer + 1) % IOREQ_BUFFER_SLOT_NUM];
+            req.data |= ((uint64_t)buf_req->data) << 32;
+        }
+
+        handle_ioreq(&req);
+
+        xen_mb();
+        state->buffered_io_page->read_pointer += qw ? 2 : 1;
+    }
+}
+
+static void handle_buffered_io(void *opaque)
+{
+    XenIOState *state = opaque;
+
+    handle_buffered_iopage(state);
+    qemu_mod_timer(state->buffered_io_timer,
+                   BUFFER_IO_MAX_DELAY + qemu_get_clock_ms(rt_clock));
+}
+
+static void cpu_handle_ioreq(void *opaque)
+{
+    XenIOState *state = opaque;
+    ioreq_t *req = cpu_get_ioreq(state);
+
+    handle_buffered_iopage(state);
+    if (req) {
+        handle_ioreq(req);
+
+        if (req->state != STATE_IOREQ_INPROCESS) {
+            fprintf(stderr, "Badness in I/O request ... not in service?!: "
+                    "%x, ptr: %x, port: %"PRIx64", "
+                    "data: %"PRIx64", count: %" FMT_ioreq_size ", size: %" FMT_ioreq_size "\n",
+                    req->state, req->data_is_ptr, req->addr,
+                    req->data, req->count, req->size);
+            destroy_hvm_domain();
+            return;
+        }
+
+        xen_wmb(); /* Update ioreq contents /then/ update state. */
+
+        /*
+         * We do this before we send the response so that the tools
+         * have the opportunity to pick up on the reset before the
+         * guest resumes and does a hlt with interrupts disabled which
+         * causes Xen to powerdown the domain.
+         */
+        if (vm_running) {
+            if (qemu_shutdown_requested_get()) {
+                destroy_hvm_domain();
+            }
+            if (qemu_reset_requested_get()) {
+                qemu_system_reset();
+            }
+        }
+
+        req->state = STATE_IORESP_READY;
+        xc_evtchn_notify(state->xce_handle, state->ioreq_local_port[state->send_vcpu]);
+    }
+}
+
+static void xenstore_record_dm_state(XenIOState *s, const char *state)
+{
+    char path[50];
+
+    snprintf(path, sizeof (path), "/local/domain/0/device-model/%u/state", xen_domid);
+    if (!xs_write(s->xenstore, XBT_NULL, path, state, strlen(state))) {
+        fprintf(stderr, "error recording dm state\n");
+        exit(1);
+    }
+}
+
+static void xen_main_loop_prepare(XenIOState *state)
+{
+    int evtchn_fd = -1;
+
+    if (state->xce_handle != XC_HANDLER_INITIAL_VALUE) {
+        evtchn_fd = xc_evtchn_fd(state->xce_handle);
+    }
+
+    state->buffered_io_timer = qemu_new_timer_ms(rt_clock, handle_buffered_io,
+                                                 state);
+    qemu_mod_timer(state->buffered_io_timer, qemu_get_clock_ms(rt_clock));
+
+    if (evtchn_fd != -1) {
+        qemu_set_fd_handler(evtchn_fd, cpu_handle_ioreq, NULL, state);
+    }
+
+    /* record state running */
+    xenstore_record_dm_state(state, "running");
+}
+
+
+/* Initialise Xen */
+
+static void xen_vm_change_state_handler(void *opaque, int running, int reason)
+{
+    XenIOState *state = opaque;
+    if (running) {
+        xen_main_loop_prepare(state);
+    }
+}
+
+static void xen_exit_notifier(Notifier *n)
+{
+    XenIOState *state = container_of(n, XenIOState, exit);
+
+    xc_evtchn_close(state->xce_handle);
+    xs_daemon_close(state->xenstore);
+}
+
+int xen_init(void)
+{
+    xen_xc = xen_xc_interface_open(0, 0, 0);
+    if (xen_xc == XC_HANDLER_INITIAL_VALUE) {
+        xen_be_printf(NULL, 0, "can't open xen interface\n");
+        return -1;
+    }
+
+    return 0;
+}
+
+int xen_hvm_init(void)
+{
+    int i, rc;
+    unsigned long ioreq_pfn;
+    XenIOState *state;
+
+    state = qemu_mallocz(sizeof (XenIOState));
+
+    state->xce_handle = xen_xc_evtchn_open(NULL, 0);
+    if (state->xce_handle == XC_HANDLER_INITIAL_VALUE) {
+        perror("xen: event channel open");
+        return -errno;
+    }
+
+    state->xenstore = xs_daemon_open();
+    if (state->xenstore == NULL) {
+        perror("xen: xenstore open");
+        return -errno;
+    }
+
+    state->exit.notify = xen_exit_notifier;
+    qemu_add_exit_notifier(&state->exit);
+
+    xc_get_hvm_param(xen_xc, xen_domid, HVM_PARAM_IOREQ_PFN, &ioreq_pfn);
+    DPRINTF("shared page at pfn %lx\n", ioreq_pfn);
+    state->shared_page = xc_map_foreign_range(xen_xc, xen_domid, XC_PAGE_SIZE,
+                                              PROT_READ|PROT_WRITE, ioreq_pfn);
+    if (state->shared_page == NULL) {
+        hw_error("map shared IO page returned error %d handle=" XC_INTERFACE_FMT,
+                 errno, xen_xc);
+    }
+
+    xc_get_hvm_param(xen_xc, xen_domid, HVM_PARAM_BUFIOREQ_PFN, &ioreq_pfn);
+    DPRINTF("buffered io page at pfn %lx\n", ioreq_pfn);
+    state->buffered_io_page = xc_map_foreign_range(xen_xc, xen_domid, XC_PAGE_SIZE,
+                                                   PROT_READ|PROT_WRITE, ioreq_pfn);
+    if (state->buffered_io_page == NULL) {
+        hw_error("map buffered IO page returned error %d", errno);
+    }
+
+    state->ioreq_local_port = qemu_mallocz(smp_cpus * sizeof (evtchn_port_t));
+
+    /* FIXME: how about if we overflow the page here? */
+    for (i = 0; i < smp_cpus; i++) {
+        rc = xc_evtchn_bind_interdomain(state->xce_handle, xen_domid,
+                                        xen_vcpu_eport(state->shared_page, i));
+        if (rc == -1) {
+            fprintf(stderr, "bind interdomain ioctl error %d\n", errno);
+            return -1;
+        }
+        state->ioreq_local_port[i] = rc;
+    }
+
+    /* Init RAM management */
+    qemu_map_cache_init();
+    xen_ram_init(ram_size);
+
+    qemu_add_vm_change_state_handler(xen_vm_change_state_handler, state);
+
+    return 0;
+}
+
+void destroy_hvm_domain(void)
+{
+    XenXC xc_handle;
+    int sts;
+
+    xc_handle = xen_xc_interface_open(0, 0, 0);
+    if (xc_handle == XC_HANDLER_INITIAL_VALUE) {
+        fprintf(stderr, "Cannot acquire xenctrl handle\n");
+    } else {
+        sts = xc_domain_shutdown(xc_handle, xen_domid, SHUTDOWN_poweroff);
+        if (sts != 0) {
+            fprintf(stderr, "? xc_domain_shutdown failed to issue poweroff, "
+                    "sts %d, %s\n", sts, strerror(errno));
+        } else {
+            fprintf(stderr, "Issued domain %d poweroff\n", xen_domid);
+        }
+        xc_interface_close(xc_handle);
+    }
+}
diff --git a/xen-mapcache-stub.c b/xen-mapcache-stub.c
new file mode 100644
index 0000000000..7c14b3d141
--- /dev/null
+++ b/xen-mapcache-stub.c
@@ -0,0 +1,44 @@
+/*
+ * Copyright (C) 2011       Citrix Ltd.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.  See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+#include "config.h"
+
+#include "exec-all.h"
+#include "qemu-common.h"
+#include "cpu-common.h"
+#include "xen-mapcache.h"
+
+void qemu_map_cache_init(void)
+{
+}
+
+uint8_t *qemu_map_cache(target_phys_addr_t phys_addr, target_phys_addr_t size, uint8_t lock)
+{
+    return qemu_get_ram_ptr(phys_addr);
+}
+
+void qemu_map_cache_unlock(void *buffer)
+{
+}
+
+ram_addr_t qemu_ram_addr_from_mapcache(void *ptr)
+{
+    return -1;
+}
+
+void qemu_invalidate_map_cache(void)
+{
+}
+
+void qemu_invalidate_entry(uint8_t *buffer)
+{
+}
+uint8_t *xen_map_block(target_phys_addr_t phys_addr, target_phys_addr_t size)
+{
+    return NULL;
+}
diff --git a/xen-mapcache.c b/xen-mapcache.c
new file mode 100644
index 0000000000..349cc6221d
--- /dev/null
+++ b/xen-mapcache.c
@@ -0,0 +1,375 @@
+/*
+ * Copyright (C) 2011       Citrix Ltd.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.  See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+#include "config.h"
+
+#include <sys/resource.h>
+
+#include "hw/xen_backend.h"
+#include "blockdev.h"
+#include "bitmap.h"
+
+#include <xen/hvm/params.h>
+#include <sys/mman.h>
+
+#include "xen-mapcache.h"
+#include "trace.h"
+
+
+//#define MAPCACHE_DEBUG
+
+#ifdef MAPCACHE_DEBUG
+#  define DPRINTF(fmt, ...) do { \
+    fprintf(stderr, "xen_mapcache: " fmt, ## __VA_ARGS__); \
+} while (0)
+#else
+#  define DPRINTF(fmt, ...) do { } while (0)
+#endif
+
+#if defined(__i386__)
+#  define MCACHE_BUCKET_SHIFT 16
+#  define MCACHE_MAX_SIZE     (1UL<<31) /* 2GB Cap */
+#elif defined(__x86_64__)
+#  define MCACHE_BUCKET_SHIFT 20
+#  define MCACHE_MAX_SIZE     (1UL<<35) /* 32GB Cap */
+#endif
+#define MCACHE_BUCKET_SIZE (1UL << MCACHE_BUCKET_SHIFT)
+
+typedef struct MapCacheEntry {
+    target_phys_addr_t paddr_index;
+    uint8_t *vaddr_base;
+    DECLARE_BITMAP(valid_mapping, MCACHE_BUCKET_SIZE >> XC_PAGE_SHIFT);
+    uint8_t lock;
+    struct MapCacheEntry *next;
+} MapCacheEntry;
+
+typedef struct MapCacheRev {
+    uint8_t *vaddr_req;
+    target_phys_addr_t paddr_index;
+    QTAILQ_ENTRY(MapCacheRev) next;
+} MapCacheRev;
+
+typedef struct MapCache {
+    MapCacheEntry *entry;
+    unsigned long nr_buckets;
+    QTAILQ_HEAD(map_cache_head, MapCacheRev) locked_entries;
+
+    /* For most cases (>99.9%), the page address is the same. */
+    target_phys_addr_t last_address_index;
+    uint8_t *last_address_vaddr;
+    unsigned long max_mcache_size;
+    unsigned int mcache_bucket_shift;
+} MapCache;
+
+static MapCache *mapcache;
+
+void qemu_map_cache_init(void)
+{
+    unsigned long size;
+    struct rlimit rlimit_as;
+
+    mapcache = qemu_mallocz(sizeof (MapCache));
+
+    QTAILQ_INIT(&mapcache->locked_entries);
+    mapcache->last_address_index = -1;
+
+    getrlimit(RLIMIT_AS, &rlimit_as);
+    if (rlimit_as.rlim_max < MCACHE_MAX_SIZE) {
+        rlimit_as.rlim_cur = rlimit_as.rlim_max;
+    } else {
+        rlimit_as.rlim_cur = MCACHE_MAX_SIZE;
+    }
+
+    setrlimit(RLIMIT_AS, &rlimit_as);
+    mapcache->max_mcache_size = rlimit_as.rlim_cur;
+
+    mapcache->nr_buckets =
+        (((mapcache->max_mcache_size >> XC_PAGE_SHIFT) +
+          (1UL << (MCACHE_BUCKET_SHIFT - XC_PAGE_SHIFT)) - 1) >>
+         (MCACHE_BUCKET_SHIFT - XC_PAGE_SHIFT));
+
+    size = mapcache->nr_buckets * sizeof (MapCacheEntry);
+    size = (size + XC_PAGE_SIZE - 1) & ~(XC_PAGE_SIZE - 1);
+    DPRINTF("qemu_map_cache_init, nr_buckets = %lx size %lu\n", mapcache->nr_buckets, size);
+    mapcache->entry = qemu_mallocz(size);
+}
+
+static void qemu_remap_bucket(MapCacheEntry *entry,
+                              target_phys_addr_t size,
+                              target_phys_addr_t address_index)
+{
+    uint8_t *vaddr_base;
+    xen_pfn_t *pfns;
+    int *err;
+    unsigned int i;
+    target_phys_addr_t nb_pfn = size >> XC_PAGE_SHIFT;
+
+    trace_qemu_remap_bucket(address_index);
+
+    pfns = qemu_mallocz(nb_pfn * sizeof (xen_pfn_t));
+    err = qemu_mallocz(nb_pfn * sizeof (int));
+
+    if (entry->vaddr_base != NULL) {
+        if (munmap(entry->vaddr_base, size) != 0) {
+            perror("unmap fails");
+            exit(-1);
+        }
+    }
+
+    for (i = 0; i < nb_pfn; i++) {
+        pfns[i] = (address_index << (MCACHE_BUCKET_SHIFT-XC_PAGE_SHIFT)) + i;
+    }
+
+    vaddr_base = xc_map_foreign_bulk(xen_xc, xen_domid, PROT_READ|PROT_WRITE,
+                                     pfns, err, nb_pfn);
+    if (vaddr_base == NULL) {
+        perror("xc_map_foreign_bulk");
+        exit(-1);
+    }
+
+    entry->vaddr_base = vaddr_base;
+    entry->paddr_index = address_index;
+
+    bitmap_zero(entry->valid_mapping, nb_pfn);
+    for (i = 0; i < nb_pfn; i++) {
+        if (!err[i]) {
+            bitmap_set(entry->valid_mapping, i, 1);
+        }
+    }
+
+    qemu_free(pfns);
+    qemu_free(err);
+}
+
+uint8_t *qemu_map_cache(target_phys_addr_t phys_addr, target_phys_addr_t size, uint8_t lock)
+{
+    MapCacheEntry *entry, *pentry = NULL;
+    target_phys_addr_t address_index  = phys_addr >> MCACHE_BUCKET_SHIFT;
+    target_phys_addr_t address_offset = phys_addr & (MCACHE_BUCKET_SIZE - 1);
+
+    trace_qemu_map_cache(phys_addr);
+
+    if (address_index == mapcache->last_address_index && !lock) {
+        trace_qemu_map_cache_return(mapcache->last_address_vaddr + address_offset);
+        return mapcache->last_address_vaddr + address_offset;
+    }
+
+    entry = &mapcache->entry[address_index % mapcache->nr_buckets];
+
+    while (entry && entry->lock && entry->paddr_index != address_index && entry->vaddr_base) {
+        pentry = entry;
+        entry = entry->next;
+    }
+    if (!entry) {
+        entry = qemu_mallocz(sizeof (MapCacheEntry));
+        pentry->next = entry;
+        qemu_remap_bucket(entry, size ? : MCACHE_BUCKET_SIZE, address_index);
+    } else if (!entry->lock) {
+        if (!entry->vaddr_base || entry->paddr_index != address_index ||
+            !test_bit(address_offset >> XC_PAGE_SHIFT, entry->valid_mapping)) {
+            qemu_remap_bucket(entry, size ? : MCACHE_BUCKET_SIZE, address_index);
+        }
+    }
+
+    if (!test_bit(address_offset >> XC_PAGE_SHIFT, entry->valid_mapping)) {
+        mapcache->last_address_index = -1;
+        trace_qemu_map_cache_return(NULL);
+        return NULL;
+    }
+
+    mapcache->last_address_index = address_index;
+    mapcache->last_address_vaddr = entry->vaddr_base;
+    if (lock) {
+        MapCacheRev *reventry = qemu_mallocz(sizeof(MapCacheRev));
+        entry->lock++;
+        reventry->vaddr_req = mapcache->last_address_vaddr + address_offset;
+        reventry->paddr_index = mapcache->last_address_index;
+        QTAILQ_INSERT_HEAD(&mapcache->locked_entries, reventry, next);
+    }
+
+    trace_qemu_map_cache_return(mapcache->last_address_vaddr + address_offset);
+    return mapcache->last_address_vaddr + address_offset;
+}
+
+void qemu_map_cache_unlock(void *buffer)
+{
+    MapCacheEntry *entry = NULL, *pentry = NULL;
+    MapCacheRev *reventry;
+    target_phys_addr_t paddr_index;
+    int found = 0;
+
+    QTAILQ_FOREACH(reventry, &mapcache->locked_entries, next) {
+        if (reventry->vaddr_req == buffer) {
+            paddr_index = reventry->paddr_index;
+            found = 1;
+            break;
+        }
+    }
+    if (!found) {
+        return;
+    }
+    QTAILQ_REMOVE(&mapcache->locked_entries, reventry, next);
+    qemu_free(reventry);
+
+    entry = &mapcache->entry[paddr_index % mapcache->nr_buckets];
+    while (entry && entry->paddr_index != paddr_index) {
+        pentry = entry;
+        entry = entry->next;
+    }
+    if (!entry) {
+        return;
+    }
+    if (entry->lock > 0) {
+        entry->lock--;
+    }
+}
+
+ram_addr_t qemu_ram_addr_from_mapcache(void *ptr)
+{
+    MapCacheRev *reventry;
+    target_phys_addr_t paddr_index;
+    int found = 0;
+
+    QTAILQ_FOREACH(reventry, &mapcache->locked_entries, next) {
+        if (reventry->vaddr_req == ptr) {
+            paddr_index = reventry->paddr_index;
+            found = 1;
+            break;
+        }
+    }
+    if (!found) {
+        fprintf(stderr, "qemu_ram_addr_from_mapcache, could not find %p\n", ptr);
+        QTAILQ_FOREACH(reventry, &mapcache->locked_entries, next) {
+            DPRINTF("   "TARGET_FMT_plx" -> %p is present\n", reventry->paddr_index,
+                    reventry->vaddr_req);
+        }
+        abort();
+        return 0;
+    }
+
+    return paddr_index << MCACHE_BUCKET_SHIFT;
+}
+
+void qemu_invalidate_entry(uint8_t *buffer)
+{
+    MapCacheEntry *entry = NULL, *pentry = NULL;
+    MapCacheRev *reventry;
+    target_phys_addr_t paddr_index;
+    int found = 0;
+
+    if (mapcache->last_address_vaddr == buffer) {
+        mapcache->last_address_index = -1;
+    }
+
+    QTAILQ_FOREACH(reventry, &mapcache->locked_entries, next) {
+        if (reventry->vaddr_req == buffer) {
+            paddr_index = reventry->paddr_index;
+            found = 1;
+            break;
+        }
+    }
+    if (!found) {
+        DPRINTF("qemu_invalidate_entry, could not find %p\n", buffer);
+        QTAILQ_FOREACH(reventry, &mapcache->locked_entries, next) {
+            DPRINTF("   "TARGET_FMT_plx" -> %p is present\n", reventry->paddr_index, reventry->vaddr_req);
+        }
+        return;
+    }
+    QTAILQ_REMOVE(&mapcache->locked_entries, reventry, next);
+    qemu_free(reventry);
+
+    entry = &mapcache->entry[paddr_index % mapcache->nr_buckets];
+    while (entry && entry->paddr_index != paddr_index) {
+        pentry = entry;
+        entry = entry->next;
+    }
+    if (!entry) {
+        DPRINTF("Trying to unmap address %p that is not in the mapcache!\n", buffer);
+        return;
+    }
+    entry->lock--;
+    if (entry->lock > 0 || pentry == NULL) {
+        return;
+    }
+
+    pentry->next = entry->next;
+    if (munmap(entry->vaddr_base, MCACHE_BUCKET_SIZE) != 0) {
+        perror("unmap fails");
+        exit(-1);
+    }
+    qemu_free(entry);
+}
+
+void qemu_invalidate_map_cache(void)
+{
+    unsigned long i;
+    MapCacheRev *reventry;
+
+    /* Flush pending AIO before destroying the mapcache */
+    qemu_aio_flush();
+
+    QTAILQ_FOREACH(reventry, &mapcache->locked_entries, next) {
+        DPRINTF("There should be no locked mappings at this time, "
+                "but "TARGET_FMT_plx" -> %p is present\n",
+                reventry->paddr_index, reventry->vaddr_req);
+    }
+
+    mapcache_lock();
+
+    for (i = 0; i < mapcache->nr_buckets; i++) {
+        MapCacheEntry *entry = &mapcache->entry[i];
+
+        if (entry->vaddr_base == NULL) {
+            continue;
+        }
+
+        if (munmap(entry->vaddr_base, MCACHE_BUCKET_SIZE) != 0) {
+            perror("unmap fails");
+            exit(-1);
+        }
+
+        entry->paddr_index = 0;
+        entry->vaddr_base = NULL;
+    }
+
+    mapcache->last_address_index = -1;
+    mapcache->last_address_vaddr = NULL;
+
+    mapcache_unlock();
+}
+
+uint8_t *xen_map_block(target_phys_addr_t phys_addr, target_phys_addr_t size)
+{
+    uint8_t *vaddr_base;
+    xen_pfn_t *pfns;
+    int *err;
+    unsigned int i;
+    target_phys_addr_t nb_pfn = size >> XC_PAGE_SHIFT;
+
+    trace_xen_map_block(phys_addr, size);
+    phys_addr >>= XC_PAGE_SHIFT;
+
+    pfns = qemu_mallocz(nb_pfn * sizeof (xen_pfn_t));
+    err = qemu_mallocz(nb_pfn * sizeof (int));
+
+    for (i = 0; i < nb_pfn; i++) {
+        pfns[i] = phys_addr + i;
+    }
+
+    vaddr_base = xc_map_foreign_bulk(xen_xc, xen_domid, PROT_READ|PROT_WRITE,
+                                     pfns, err, nb_pfn);
+    if (vaddr_base == NULL) {
+        perror("xc_map_foreign_bulk");
+        exit(-1);
+    }
+
+    qemu_free(pfns);
+    qemu_free(err);
+
+    return vaddr_base;
+}
diff --git a/xen-mapcache.h b/xen-mapcache.h
new file mode 100644
index 0000000000..339444c94e
--- /dev/null
+++ b/xen-mapcache.h
@@ -0,0 +1,37 @@
+/*
+ * Copyright (C) 2011       Citrix Ltd.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.  See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+#ifndef XEN_MAPCACHE_H
+#define XEN_MAPCACHE_H
+
+#include <sys/mman.h>
+#include "trace.h"
+
+void     qemu_map_cache_init(void);
+uint8_t  *qemu_map_cache(target_phys_addr_t phys_addr, target_phys_addr_t size, uint8_t lock);
+void     qemu_map_cache_unlock(void *phys_addr);
+ram_addr_t qemu_ram_addr_from_mapcache(void *ptr);
+void     qemu_invalidate_entry(uint8_t *buffer);
+void     qemu_invalidate_map_cache(void);
+
+uint8_t *xen_map_block(target_phys_addr_t phys_addr, target_phys_addr_t size);
+
+static inline void xen_unmap_block(void *addr, ram_addr_t size)
+{
+    trace_xen_unmap_block(addr, size);
+
+    if (munmap(addr, size) != 0) {
+        hw_error("xen_unmap_block: %s", strerror(errno));
+    }
+}
+
+
+#define mapcache_lock()   ((void)0)
+#define mapcache_unlock() ((void)0)
+
+#endif /* !XEN_MAPCACHE_H */
diff --git a/xen-stub.c b/xen-stub.c
new file mode 100644
index 0000000000..a4f35a19fb
--- /dev/null
+++ b/xen-stub.c
@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2010       Citrix Ltd.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.  See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+#include "qemu-common.h"
+#include "hw/xen.h"
+
+int xen_pci_slot_get_pirq(PCIDevice *pci_dev, int irq_num)
+{
+    return -1;
+}
+
+void xen_piix3_set_irq(void *opaque, int irq_num, int level)
+{
+}
+
+void xen_piix_pci_write_config_client(uint32_t address, uint32_t val, int len)
+{
+}
+
+void xen_cmos_set_s3_resume(void *opaque, int irq, int level)
+{
+}
+
+void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size)
+{
+}
+
+qemu_irq *xen_interrupt_controller_init(void)
+{
+    return NULL;
+}
+
+int xen_init(void)
+{
+    return -ENOSYS;
+}