Commit 77c2002e authored by Izik Eidus's avatar Izik Eidus Committed by Avi Kivity
Browse files

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: default avatarIzik Eidus <ieidus@redhat.com>
Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
parent 53f658b3

arch/x86/include/asm/kvm_host.h

+0 −4
Original line number Diff line number Diff line
@@ -609,10 +609,6 @@ void kvm_inject_nmi(struct kvm_vcpu *vcpu); 


void fx_init(struct kvm_vcpu *vcpu);



int emulator_read_std(unsigned long addr,

		      void *val,

		      unsigned int bytes,

		      struct kvm_vcpu *vcpu);

int emulator_write_emulated(unsigned long addr,

			    const void *val,

			    unsigned int bytes,

arch/x86/kvm/x86.c

+42 −14
Original line number Diff line number Diff line
@@ -1976,9 +1976,7 @@ static struct kvm_io_device *vcpu_find_mmio_dev(struct kvm_vcpu *vcpu, 
	return dev;

}



int emulator_read_std(unsigned long addr,

			     void *val,

			     unsigned int bytes,

int kvm_read_guest_virt(gva_t addr, void *val, unsigned int bytes,

			struct kvm_vcpu *vcpu)

{

	void *data = val;
@@ -1987,27 +1985,57 @@ int emulator_read_std(unsigned long addr, 
	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,
@@ -2029,7 +2057,7 @@ static int emulator_read_emulated(unsigned long addr, 
	if ((gpa & PAGE_MASK) == APIC_DEFAULT_PHYS_BASE)

		goto mmio;



	if (emulator_read_std(addr, val, bytes, vcpu)

	if (kvm_read_guest_virt(addr, val, bytes, vcpu)

				== X86EMUL_CONTINUE)

		return X86EMUL_CONTINUE;

	if (gpa == UNMAPPED_GVA)
@@ -2233,7 +2261,7 @@ void kvm_report_emulation_failure(struct kvm_vcpu *vcpu, const char *context) 


	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 @@ void kvm_report_emulation_failure(struct kvm_vcpu *vcpu, const char *context) 
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,