implement vmm_cpu_write_register

Author: nyuichi

src/hv_kvm.c

@@ -11,6 +11,9 @@
 #include <sys/types.h>
 
 int kvm, vmfd;
+struct kvm_run *run;
+struct kvm_regs regs;
+struct kvm_sregs sregs;
 
 int
 vmm_create(void)
@@ -52,7 +55,6 @@ int
 vmm_cpu_create(vmm_cpuid_t *cpu)
 {
   int cpufd;
-  struct kvm_run *run;
   int mmap_size;
 
   if ((cpufd = ioctl(vmfd, KVM_CREATE_VCPU, 0UL)) < 0)
@@ -78,32 +80,113 @@ vmm_cpu_run(vmm_cpuid_t cpu)
   return 0;
 }
 
+/*
+
+struct kvm_regs {
+  __u64 rax, rbx, rcx, rdx;
+  __u64 rsi, rdi, rsp, rbp;
+  __u64 r8,  r9,  r10, r11;
+  __u64 r12, r13, r14, r15;
+  __u64 rip, rflags;
+};
+
+struct kvm_segment {
+  __u64 base;
+  __u32 limit;
+  __u16 selector;
+  __u8  type;
+  __u8  present, dpl, db, s, l, g, avl;
+  __u8  unusable;
+  __u8  padding;
+};
+
+struct kvm_dtable {
+  __u64 base;
+  __u16 limit;
+  __u16 padding[3];
+};
+
+struct kvm_sregs {
+  struct kvm_segment cs, ds, es, fs, gs, ss;
+  struct kvm_segment tr, ldt;
+  struct kvm_dtable gdt, idt;
+  __u64 cr0, cr2, cr3, cr4, cr8;
+  __u64 efer;
+  __u64 apic_base;
+  __u64 interrupt_bitmap[(KVM_NR_INTERRUPTS + 63) / 64];
+};
+
+*/
+
 int
 vmm_cpu_write_register(vmm_cpuid_t cpu, vmm_x64_reg_t reg, uint64_t value)
 {
-  /* FIXME */
-
-  /* Initialize CS to point at 0, via a read-modify-write of sregs. */
-  ret = ioctl(vcpufd, KVM_GET_SREGS, &sregs);
-  if (ret == -1)
-    err(1, "KVM_GET_SREGS");
-  sregs.cs.base = 0;
-  sregs.cs.selector = 0;
-  ret = ioctl(vcpufd, KVM_SET_SREGS, &sregs);
-  if (ret == -1)
-    err(1, "KVM_SET_SREGS");
-
-  /* Initialize registers: instruction pointer for our code, addends, and
-   * initial flags required by x86 architecture. */
-  struct kvm_regs regs = {
-    .rip = 0x1000,
-    .rax = 2,
-    .rbx = 2,
-    .rflags = 0x2,
-  };
-  ret = ioctl(vcpufd, KVM_SET_REGS, &regs);
-  if (ret == -1)
-    err(1, "KVM_SET_REGS");
+  if (ioctl(vcpufd, KVM_GET_REGS, &regs) < 0)
+    return VMM_ERROR;
+  if (ioctl(vcpufd, KVM_GET_SREGS, &sregs) < 0)
+    return VMM_ERROR;
+
+  switch (reg) {
+  case VMM_X64_RIP:      regs.rip = value; break;
+  case VMM_X64_RFLAGS:   regs.rflags = value; break;
+  case VMM_X64_RAX:      regs.rax = value; break;
+  case VMM_X64_RBX:      regs.rbx = value; break;
+  case VMM_X64_RCX:      regs.rcx = value; break;
+  case VMM_X64_RDX:      regs.rdx = value; break;
+  case VMM_X64_RSI:      regs.rsi = value; break;
+  case VMM_X64_RDI:      regs.rdi = value; break;
+  case VMM_X64_RSP:      regs.rsp = value; break;
+  case VMM_X64_RBP:      regs.rbp = value; break;
+  case VMM_X64_R8:
+  case VMM_X64_R9:
+  case VMM_X64_R10:
+  case VMM_X64_R11:
+  case VMM_X64_R12:
+  case VMM_X64_R13:
+  case VMM_X64_R14:
+  case VMM_X64_R15:
+    assert(false);
+  case VMM_X64_CS: sregs.cs.base = value; break;
+  case VMM_X64_SS:
+  case VMM_X64_DS:
+  case VMM_X64_ES:
+  case VMM_X64_FS:
+  case VMM_X64_GS:
+  case VMM_X64_IDT_BASE:
+  case VMM_X64_IDT_LIMIT:
+  case VMM_X64_GDT_BASE:
+  case VMM_X64_GDT_LIMIT:
+  case VMM_X64_LDTR:
+  case VMM_X64_LDT_BASE:
+  case VMM_X64_LDT_LIMIT:
+  case VMM_X64_LDT_AR:
+  case VMM_X64_TR:
+  case VMM_X64_TSS_BASE:
+  case VMM_X64_TSS_LIMIT:
+  case VMM_X64_TSS_AR:
+  case VMM_X64_CR0:
+  case VMM_X64_CR1:
+  case VMM_X64_CR2:
+  case VMM_X64_CR3:
+  case VMM_X64_CR4:
+  case VMM_X64_DR0:
+  case VMM_X64_DR1:
+  case VMM_X64_DR2:
+  case VMM_X64_DR3:
+  case VMM_X64_DR4:
+  case VMM_X64_DR5:
+  case VMM_X64_DR6:
+  case VMM_X64_DR7:
+  case VMM_X64_TPR:
+  case VMM_X64_XCR0:
+  default:
+    assert(false);
+  }
+
+  if (ioctl(vcpufd, KVM_SET_REGS, &regs) < 0)
+    return VMM_ERROR;
+  if (ioctl(vcpufd, KVM_SET_SREGS, &sregs) < 0)
+    return VMM_ERROR;
 
   return 0;
 }

test/main.c

@@ -24,11 +24,11 @@
  * IN THE SOFTWARE.
  */
 
-#include <hv.h>
+#include "hv.h"
+#include <stdio.h>
 
 int main(void)
 {
-  int kvm, vmfd, ret;
   unsigned cpu;
   const uint8_t code[] = {
     0xba, 0xf8, 0x03, /* mov $0x3f8, %dx */
@@ -40,8 +40,6 @@ int main(void)
     0xf4,             /* hlt */
   };
   uint8_t *mem;
-  struct kvm_sregs sregs;
-  size_t mmap_size;
 
   vmm_create();