[PATCH] x86/svm: Provide EXITINFO decodes for IO intercetps

[Andrew Cooper <andrew.cooper3@xxxxxxxxxx>]

This removes raw number manipulation, and makes the logic easier to follow.

No functional change.

Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
---
CC: Jan Beulich <JBeulich@xxxxxxxx>
CC: Roger Pau Monné <roger.pau@xxxxxxxxxx>
CC: Wei Liu <wl@xxxxxxx>
---
 xen/arch/x86/hvm/svm/svm.c              | 11 +++++------
 xen/arch/x86/include/asm/hvm/svm/vmcb.h | 14 ++++++++++++++
 2 files changed, 19 insertions(+), 6 deletions(-)

diff --git a/xen/arch/x86/hvm/svm/svm.c b/xen/arch/x86/hvm/svm/svm.c
index a43bcf2e92f0..bfe03316def6 100644
--- a/xen/arch/x86/hvm/svm/svm.c
+++ b/xen/arch/x86/hvm/svm/svm.c
@@ -2939,13 +2939,12 @@ void svm_vmexit_handler(void)
         break;
 
     case VMEXIT_IOIO:
-        if ( (vmcb->exitinfo1 & (1u<<2)) == 0 )
+        if ( !vmcb->ei.io.str )
         {
-            uint16_t port = (vmcb->exitinfo1 >> 16) & 0xFFFF;
-            int bytes = ((vmcb->exitinfo1 >> 4) & 0x07);
-            int dir = (vmcb->exitinfo1 & 1) ? IOREQ_READ : IOREQ_WRITE;
-            if ( handle_pio(port, bytes, dir) )
-                __update_guest_eip(regs, vmcb->exitinfo2 - vmcb->rip);
+            if ( handle_pio(vmcb->ei.io.port,
+                            vmcb->ei.io.bytes,
+                            vmcb->ei.io.in ? IOREQ_READ : IOREQ_WRITE) )
+                __update_guest_eip(regs, vmcb->ei.io.nrip - vmcb->rip);
         }
         else if ( !hvm_emulate_one_insn(x86_insn_is_portio, "port I/O") )
             hvm_inject_hw_exception(TRAP_gp_fault, 0);
diff --git a/xen/arch/x86/include/asm/hvm/svm/vmcb.h 
b/xen/arch/x86/include/asm/hvm/svm/vmcb.h
index e87728fa81cd..2981a303746a 100644
--- a/xen/arch/x86/include/asm/hvm/svm/vmcb.h
+++ b/xen/arch/x86/include/asm/hvm/svm/vmcb.h
@@ -436,6 +436,20 @@ struct vmcb_struct {
             uint64_t exitinfo2; /* offset 0x80 */
         };
         union {
+            struct {
+                bool     in:1;
+                bool     :1;
+                bool     str:1;
+                bool     /* rep */:1;
+                uint16_t bytes:3;
+                uint16_t /* asz */:3;
+                uint16_t /* seg */:3;
+                uint16_t :3;
+                uint16_t port;
+                uint32_t :32;
+
+                uint64_t nrip;
+            } io;
             struct {
                 uint16_t sel;
                 uint64_t :48;
-- 
2.30.2