KVM: introduce kvm_read_guest_virt, kvm_write_guest_virt
This commit change the name of emulator_read_std into kvm_read_guest_virt,
and add new function name kvm_write_guest_virt that allow writing into a
guest virtual address.
Signed-off-by: Izik Eidus <ieidus@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 3b2acfd..67f9176 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1976,10 +1976,8 @@
return dev;
}
-int emulator_read_std(unsigned long addr,
- void *val,
- unsigned int bytes,
- struct kvm_vcpu *vcpu)
+int kvm_read_guest_virt(gva_t addr, void *val, unsigned int bytes,
+ struct kvm_vcpu *vcpu)
{
void *data = val;
int r = X86EMUL_CONTINUE;
@@ -1987,27 +1985,57 @@
while (bytes) {
gpa_t gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, addr);
unsigned offset = addr & (PAGE_SIZE-1);
- unsigned tocopy = min(bytes, (unsigned)PAGE_SIZE - offset);
+ unsigned toread = min(bytes, (unsigned)PAGE_SIZE - offset);
int ret;
if (gpa == UNMAPPED_GVA) {
r = X86EMUL_PROPAGATE_FAULT;
goto out;
}
- ret = kvm_read_guest(vcpu->kvm, gpa, data, tocopy);
+ ret = kvm_read_guest(vcpu->kvm, gpa, data, toread);
if (ret < 0) {
r = X86EMUL_UNHANDLEABLE;
goto out;
}
- bytes -= tocopy;
- data += tocopy;
- addr += tocopy;
+ bytes -= toread;
+ data += toread;
+ addr += toread;
}
out:
return r;
}
-EXPORT_SYMBOL_GPL(emulator_read_std);
+
+int kvm_write_guest_virt(gva_t addr, void *val, unsigned int bytes,
+ struct kvm_vcpu *vcpu)
+{
+ void *data = val;
+ int r = X86EMUL_CONTINUE;
+
+ while (bytes) {
+ gpa_t gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, addr);
+ unsigned offset = addr & (PAGE_SIZE-1);
+ unsigned towrite = min(bytes, (unsigned)PAGE_SIZE - offset);
+ int ret;
+
+ if (gpa == UNMAPPED_GVA) {
+ r = X86EMUL_PROPAGATE_FAULT;
+ goto out;
+ }
+ ret = kvm_write_guest(vcpu->kvm, gpa, data, towrite);
+ if (ret < 0) {
+ r = X86EMUL_UNHANDLEABLE;
+ goto out;
+ }
+
+ bytes -= towrite;
+ data += towrite;
+ addr += towrite;
+ }
+out:
+ return r;
+}
+
static int emulator_read_emulated(unsigned long addr,
void *val,
@@ -2029,8 +2057,8 @@
if ((gpa & PAGE_MASK) == APIC_DEFAULT_PHYS_BASE)
goto mmio;
- if (emulator_read_std(addr, val, bytes, vcpu)
- == X86EMUL_CONTINUE)
+ if (kvm_read_guest_virt(addr, val, bytes, vcpu)
+ == X86EMUL_CONTINUE)
return X86EMUL_CONTINUE;
if (gpa == UNMAPPED_GVA)
return X86EMUL_PROPAGATE_FAULT;
@@ -2233,7 +2261,7 @@
rip_linear = rip + get_segment_base(vcpu, VCPU_SREG_CS);
- emulator_read_std(rip_linear, (void *)opcodes, 4, vcpu);
+ kvm_read_guest_virt(rip_linear, (void *)opcodes, 4, vcpu);
printk(KERN_ERR "emulation failed (%s) rip %lx %02x %02x %02x %02x\n",
context, rip, opcodes[0], opcodes[1], opcodes[2], opcodes[3]);
@@ -2241,7 +2269,7 @@
EXPORT_SYMBOL_GPL(kvm_report_emulation_failure);
static struct x86_emulate_ops emulate_ops = {
- .read_std = emulator_read_std,
+ .read_std = kvm_read_guest_virt,
.read_emulated = emulator_read_emulated,
.write_emulated = emulator_write_emulated,
.cmpxchg_emulated = emulator_cmpxchg_emulated,