[PATCH] QEMU-KVM - provide e820 reserve through qemu_cfg

[Jes Sorensen <Jes.Sorensen@xxxxxxxxxx>]

Hi,

This is the QEMU-KVM bits for providing the e820-reserve space through
qemu-cfg.

Cheers,
Jes

Use qemu-cfg to notify the BIOS of the location of the TSS range to
reserve in the e820 table, to avoid relying on hard coded values.

Signed-off-by: Jes Sorensen <Jes.Sorensen@xxxxxxxxxx>

---
 hw/fw_cfg.h       |    5 +++++
 hw/pc.c           |    4 ++++
 kvm.h             |    2 ++
 qemu-kvm-x86.c    |    6 ++++++
 target-i386/kvm.c |    7 +++++++
 5 files changed, 24 insertions(+)

Index: qemu-kvm/hw/fw_cfg.h
===================================================================
--- qemu-kvm.orig/hw/fw_cfg.h
+++ qemu-kvm/hw/fw_cfg.h
@@ -67,4 +67,9 @@ FWCfgState *fw_cfg_init(uint32_t ctl_por
 
 #endif /* NO_QEMU_PROTOS */
 
+struct fw_cfg_e820_reserve {
+    uint32_t addr;
+    uint32_t length;
+};
+
 #endif
Index: qemu-kvm/hw/pc.c
===================================================================
--- qemu-kvm.orig/hw/pc.c
+++ qemu-kvm/hw/pc.c
@@ -66,6 +66,7 @@
 #define FW_CFG_ACPI_TABLES (FW_CFG_ARCH_LOCAL + 0)
 #define FW_CFG_SMBIOS_ENTRIES (FW_CFG_ARCH_LOCAL + 1)
 #define FW_CFG_IRQ0_OVERRIDE (FW_CFG_ARCH_LOCAL + 2)
+#define FW_CFG_E820_RESERVE (FW_CFG_ARCH_LOCAL + 3)
 
 #define MAX_IDE_BUS 2
 
@@ -73,6 +74,7 @@ static fdctrl_t *floppy_controller;
 static RTCState *rtc_state;
 static PITState *pit;
 static PCII440FXState *i440fx_state;
+struct fw_cfg_e820_reserve e820_reserve;
 
 qemu_irq *ioapic_irq_hack;
 
@@ -475,6 +477,8 @@ static void *bochs_bios_init(void)
     if (smbios_table)
         fw_cfg_add_bytes(fw_cfg, FW_CFG_SMBIOS_ENTRIES,
                          smbios_table, smbios_len);
+    fw_cfg_add_bytes(fw_cfg, FW_CFG_E820_RESERVE, (uint8_t *)&e820_reserve,
+                     sizeof(struct fw_cfg_e820_reserve));
 
     /* allocate memory for the NUMA channel: one (64bit) word for the number
      * of nodes, one word for each VCPU->node and one word for each node to
Index: qemu-kvm/kvm.h
===================================================================
--- qemu-kvm.orig/kvm.h
+++ qemu-kvm/kvm.h
@@ -101,6 +101,8 @@ void kvm_arch_reset_vcpu(CPUState *env);
 struct kvm_guest_debug;
 struct kvm_debug_exit_arch;
 
+extern struct fw_cfg_e820_reserve e820_reserve;
+
 struct kvm_sw_breakpoint {
     target_ulong pc;
     target_ulong saved_insn;
Index: qemu-kvm/qemu-kvm-x86.c
===================================================================
--- qemu-kvm.orig/qemu-kvm-x86.c
+++ qemu-kvm/qemu-kvm-x86.c
@@ -23,6 +23,7 @@
 
 #include "kvm.h"
 #include "hw/pc.h"
+#include "hw/fw_cfg.h"
 
 #define MSR_IA32_TSC		0x10
 
@@ -37,6 +38,11 @@ int kvm_set_tss_addr(kvm_context_t kvm, 
 {
 #ifdef KVM_CAP_SET_TSS_ADDR
 	int r;
+        /*
+         * Tell fw_cfg to notify the BIOS to reserve the range.
+         */
+        e820_reserve.addr = addr;
+        e820_reserve.length = 0x4000;
 
 	r = kvm_ioctl(kvm_state, KVM_CHECK_EXTENSION, KVM_CAP_SET_TSS_ADDR);
 	if (r > 0) {
Index: qemu-kvm/target-i386/kvm.c
===================================================================
--- qemu-kvm.orig/target-i386/kvm.c
+++ qemu-kvm/target-i386/kvm.c
@@ -25,6 +25,8 @@
 #include "gdbstub.h"
 #include "host-utils.h"
 
+extern struct fw_cfg_e820_reserve e820_reserve;
+
 #ifdef KVM_UPSTREAM
 //#define DEBUG_KVM
 
@@ -298,6 +300,11 @@ int kvm_arch_init(KVMState *s, int smp_c
      * as unavaible memory.  FIXME, need to ensure the e820 map deals with
      * this?
      */
+    /*
+     * Tell fw_cfg to notify the BIOS to reserve the range.
+     */
+    e820_reserve.addr = 0xfffbc000;
+    e820_reserve.length = 0x4000;
     return kvm_vm_ioctl(s, KVM_SET_TSS_ADDR, 0xfffbd000);
 }