[PATCH] xen: start PCI hole at 0xe0000000 (same as pc_init1 and qemu-xen-traditional)

[Stefano Stabellini <stefano.stabellini@eu.citrix.com>]

We are currently setting the PCI hole to start at HVM_BELOW_4G_RAM_END,
that is 0xf0000000.
Start the PCI hole at 0xe0000000 instead, that is the same value used by
pc_init1 and qemu-xen-traditional.

This fixes a bug with device assignment of graphic cards with large
amount of video memory (http://marc.info/?l=xen-devel&m=136242365010750).

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
CC: qemu-stable@nongnu.org
CC: pbonzini@redhat.com
CC: afaerber@suse.de
CC: hanweidong@huawei.com
CC: arei.gonglei@huawei.com
---
 hw/i386/pc_piix.c    |    6 +++---
 include/hw/i386/pc.h |    3 +++
 xen-all.c            |   12 ++++++------
 3 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
index 43ab480..06416ce 100644
--- a/hw/i386/pc_piix.c
+++ b/hw/i386/pc_piix.c
@@ -102,9 +102,9 @@ static void pc_init1(MemoryRegion *system_memory,
         kvmclock_create();
     }
 
-    if (ram_size >= 0xe0000000 ) {
-        above_4g_mem_size = ram_size - 0xe0000000;
-        below_4g_mem_size = 0xe0000000;
+    if (ram_size >= QEMU_BELOW_4G_RAM_END ) {
+        above_4g_mem_size = ram_size - QEMU_BELOW_4G_RAM_END;
+        below_4g_mem_size = QEMU_BELOW_4G_RAM_END;
     } else {
         above_4g_mem_size = 0;
         below_4g_mem_size = ram_size;
diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
index 663426c..626442b 100644
--- a/include/hw/i386/pc.h
+++ b/include/hw/i386/pc.h
@@ -77,6 +77,9 @@ extern int fd_bootchk;
 void pc_register_ferr_irq(qemu_irq irq);
 void pc_acpi_smi_interrupt(void *opaque, int irq, int level);
 
+#define QEMU_BELOW_4G_RAM_END       0xe0000000
+#define QEMU_BELOW_4G_MMIO_LENGTH   ((1ULL << 32) - QEMU_BELOW_4G_RAM_END)
+
 void pc_cpus_init(const char *cpu_model, DeviceState *icc_bridge);
 void pc_hot_add_cpu(const int64_t id, Error **errp);
 void pc_acpi_init(const char *default_dsdt);
diff --git a/xen-all.c b/xen-all.c
index 539a154..5ca0c26 100644
--- a/xen-all.c
+++ b/xen-all.c
@@ -161,18 +161,18 @@ static void xen_ram_init(ram_addr_t ram_size)
     ram_addr_t block_len;
 
     block_len = ram_size;
-    if (ram_size >= HVM_BELOW_4G_RAM_END) {
+    if (ram_size >= QEMU_BELOW_4G_RAM_END) {
         /* Xen does not allocate the memory continuously, and keep a hole at
-         * HVM_BELOW_4G_MMIO_START of HVM_BELOW_4G_MMIO_LENGTH
+         * QEMU_BELOW_4G_RAM_END of QEMU_BELOW_4G_MMIO_LENGTH
          */
-        block_len += HVM_BELOW_4G_MMIO_LENGTH;
+        block_len += QEMU_BELOW_4G_MMIO_LENGTH;
     }
     memory_region_init_ram(&ram_memory, "xen.ram", block_len);
     vmstate_register_ram_global(&ram_memory);
 
-    if (ram_size >= HVM_BELOW_4G_RAM_END) {
-        above_4g_mem_size = ram_size - HVM_BELOW_4G_RAM_END;
-        below_4g_mem_size = HVM_BELOW_4G_RAM_END;
+    if (ram_size >= QEMU_BELOW_4G_RAM_END) {
+        above_4g_mem_size = ram_size - QEMU_BELOW_4G_RAM_END;
+        below_4g_mem_size = QEMU_BELOW_4G_RAM_END;
     } else {
         below_4g_mem_size = ram_size;
     }
-- 
1.7.2.5