[xen master] x86/vmx: Provide named fields for IO exit qualification

[patchbot@xxxxxxx]

commit f71f8e95c34fedb0d9ae21a100bfa9f012543abf
Author:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
AuthorDate: Thu Mar 16 17:53:56 2023 +0000
Commit:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
CommitDate: Tue Mar 21 10:41:16 2023 +0000

    x86/vmx: Provide named fields for IO exit qualification
    
    This removes most of the opencoded bit logic on the exit qualification.
    Unfortunately, size is 1-based not 0-based, so need adjusting in a separate
    variable.
    
    No functional change.
    
    Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
    Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>
---
 xen/arch/x86/hvm/vmx/vmx.c | 30 ++++++++++++++++++++++--------
 1 file changed, 22 insertions(+), 8 deletions(-)

diff --git a/xen/arch/x86/hvm/vmx/vmx.c b/xen/arch/x86/hvm/vmx/vmx.c
index 00b531f76c..78ac9ece6f 100644
--- a/xen/arch/x86/hvm/vmx/vmx.c
+++ b/xen/arch/x86/hvm/vmx/vmx.c
@@ -4560,23 +4560,37 @@ void vmx_vmexit_handler(struct cpu_user_regs *regs)
         break;
 
     case EXIT_REASON_IO_INSTRUCTION:
-        __vmread(EXIT_QUALIFICATION, &exit_qualification);
-        if ( exit_qualification & 0x10 )
+    {
+        union {
+            unsigned long raw;
+            struct {
+                uint16_t size:3;
+                bool     in:1;
+                bool     str:1;
+                bool     rep:1;
+                bool     imm:1;
+                uint16_t :9;
+                uint16_t port;
+            };
+        } io_qual;
+        unsigned int bytes;
+
+        __vmread(EXIT_QUALIFICATION, &io_qual.raw);
+        bytes = io_qual.size + 1;
+
+        if ( io_qual.str )
         {
-            /* INS, OUTS */
             if ( !hvm_emulate_one_insn(x86_insn_is_portio, "port I/O") )
                 hvm_inject_hw_exception(TRAP_gp_fault, 0);
         }
         else
         {
-            /* IN, OUT */
-            uint16_t port = (exit_qualification >> 16) & 0xFFFF;
-            int bytes = (exit_qualification & 0x07) + 1;
-            int dir = (exit_qualification & 0x08) ? IOREQ_READ : IOREQ_WRITE;
-            if ( handle_pio(port, bytes, dir) )
+            if ( handle_pio(io_qual.port, bytes,
+                            io_qual.in ? IOREQ_READ : IOREQ_WRITE) )
                 update_guest_eip(); /* Safe: IN, OUT */
         }
         break;
+    }
 
     case EXIT_REASON_INVD:
     case EXIT_REASON_WBINVD:
--
generated by git-patchbot for /home/xen/git/xen.git#master