KVM: Cleanup string I/O instruction emulation
Both vmx and svm decode the I/O instructions, and both botch the job,
requiring the instruction prefixes to be fetched in order to completely
decode the instruction.
So, if we see a string I/O instruction, use the x86 emulator to decode it,
as it already has all the prefix decoding machinery.
This patch defines ins/outs opcodes in x86_emulate.c and calls
emulate_instruction() from io_interception() (svm.c) and from handle_io()
(vmx.c). It removes all vmx/svm prefix instruction decoders
(get_addr_size(), io_get_override(), io_address(), get_io_count())
Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net>
Signed-off-by: Avi Kivity <avi@qumranet.com>
diff --git a/drivers/kvm/x86_emulate.c b/drivers/kvm/x86_emulate.c
index 44eb28d..d553719f 100644
--- a/drivers/kvm/x86_emulate.c
+++ b/drivers/kvm/x86_emulate.c
@@ -103,9 +103,12 @@
/* 0x58 - 0x5F */
ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,
ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,
- /* 0x60 - 0x6F */
+ /* 0x60 - 0x6B */
0, 0, 0, DstReg | SrcMem32 | ModRM | Mov /* movsxd (x86/64) */ ,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ /* 0x6C - 0x6F */
+ SrcNone | ByteOp | ImplicitOps, SrcNone | ImplicitOps, /* insb, insw/insd */
+ SrcNone | ByteOp | ImplicitOps, SrcNone | ImplicitOps, /* outsb, outsw/outsd */
/* 0x70 - 0x7F */
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
/* 0x80 - 0x87 */
@@ -428,10 +431,11 @@
})
/* Access/update address held in a register, based on addressing mode. */
+#define address_mask(reg) \
+ ((ad_bytes == sizeof(unsigned long)) ? \
+ (reg) : ((reg) & ((1UL << (ad_bytes << 3)) - 1)))
#define register_address(base, reg) \
- ((base) + ((ad_bytes == sizeof(unsigned long)) ? (reg) : \
- ((reg) & ((1UL << (ad_bytes << 3)) - 1))))
-
+ ((base) + address_mask(reg))
#define register_address_increment(reg, inc) \
do { \
/* signed type ensures sign extension to long */ \
@@ -1116,6 +1120,41 @@
special_insn:
if (twobyte)
goto twobyte_special_insn;
+ switch(b) {
+ case 0x6c: /* insb */
+ case 0x6d: /* insw/insd */
+ if (kvm_setup_pio(ctxt->vcpu, NULL,
+ 1, /* in */
+ (d & ByteOp) ? 1 : op_bytes, /* size */
+ rep_prefix ?
+ address_mask(_regs[VCPU_REGS_RCX]) : 1, /* count */
+ 1, /* strings */
+ (_eflags & EFLG_DF), /* down */
+ register_address(ctxt->es_base,
+ _regs[VCPU_REGS_RDI]), /* address */
+ rep_prefix,
+ _regs[VCPU_REGS_RDX] /* port */
+ ) == 0)
+ return -1;
+ return 0;
+ case 0x6e: /* outsb */
+ case 0x6f: /* outsw/outsd */
+ if (kvm_setup_pio(ctxt->vcpu, NULL,
+ 0, /* in */
+ (d & ByteOp) ? 1 : op_bytes, /* size */
+ rep_prefix ?
+ address_mask(_regs[VCPU_REGS_RCX]) : 1, /* count */
+ 1, /* strings */
+ (_eflags & EFLG_DF), /* down */
+ register_address(override_base ?
+ *override_base : ctxt->ds_base,
+ _regs[VCPU_REGS_RSI]), /* address */
+ rep_prefix,
+ _regs[VCPU_REGS_RDX] /* port */
+ ) == 0)
+ return -1;
+ return 0;
+ }
if (rep_prefix) {
if (_regs[VCPU_REGS_RCX] == 0) {
ctxt->vcpu->rip = _eip;