[PATCH 1/3] include/hw/hyperv: add ABI for exception intercepts and pending events

["Doru Blânzeanu" <dblanzeanu@linux.microsoft.com>]

Import the hypervisor definitions needed to intercept guest exceptions
and to inject events back into a guest, in preparation for gdbstub
debugging support in the MSHV accelerator.

Add:
  - union hv_intercept_parameters, struct hv_input_install_intercept and
    HVCALL_INSTALL_INTERCEPT, used to install an exception intercept on
    the partition;
  - struct hv_x64_exception_intercept_message, the message delivered on
    an intercepted exception, carrying the faulting RIP, the exception
    vector and the instruction bytes;
  - HV_X64_PENDING_EVENT_EXCEPTION, the pending-event type for an
    exception.

These definitions mirror the hypervisor headers and have no functional
effect on their own.

Signed-off-by: Doru Blânzeanu <dblanzeanu@linux.microsoft.com>
---
 include/hw/hyperv/hvgdk_mini.h | 56 ++++++++++++++++++++++++++++++++++
 1 file changed, 56 insertions(+)

diff --git a/include/hw/hyperv/hvgdk_mini.h b/include/hw/hyperv/hvgdk_mini.h
index f8838a31bb..c81928d0c2 100644
--- a/include/hw/hyperv/hvgdk_mini.h
+++ b/include/hw/hyperv/hvgdk_mini.h
@@ -22,6 +22,9 @@
 #define HV_X64_MSR_TSC_FREQUENCY    0x40000022
 #define HV_X64_MSR_APIC_FREQUENCY   0x40000023
 
+/* event_type values for hv_x64_pending_exception_event */
+#define HV_X64_PENDING_EVENT_EXCEPTION 0
+
 typedef enum hv_register_name {
     /* Pending Interruption Register */
     HV_REGISTER_PENDING_INTERRUPTION = 0x00010002,
@@ -236,6 +239,29 @@ enum hv_intercept_type {
     HV_INTERCEPT_TYPE_INVALID               = 0XFFFFFFFF,
 };
 
+union hv_intercept_parameters {
+    /* HV_INTERCEPT_PARAMETERS is defined to be an 8-byte field. */
+    uint64_t as_uint64;
+    /* HV_INTERCEPT_TYPE_X64_IO_PORT */
+    uint16_t io_port;
+    /* HV_INTERCEPT_TYPE_X64_CPUID */
+    uint32_t cpuid_index;
+    /* HV_INTERCEPT_TYPE_X64_APIC_WRITE */
+    uint32_t apic_write_mask;
+    /* HV_INTERCEPT_TYPE_EXCEPTION */
+    uint16_t exception_vector;
+    /* HV_INTERCEPT_TYPE_X64_MSR_INDEX */
+    uint32_t msr_index;
+    /* N.B. Other intercept types do not have any parameters. */
+};
+
+struct hv_input_install_intercept {
+    uint64_t partition_id;
+    uint32_t access_type; /* mask */
+    uint32_t intercept_type; /* enum hv_intercept_type */
+    union hv_intercept_parameters intercept_parameter;
+} QEMU_PACKED;
+
 struct hv_u128 {
     uint64_t low_part;
     uint64_t high_part;
@@ -836,6 +862,35 @@ struct hv_x64_memory_intercept_message {
     uint8_t instruction_bytes[16];
 } QEMU_PACKED;
 
+struct hv_x64_exception_intercept_message {
+    struct hv_x64_intercept_message_header header;
+    uint16_t exception_vector;
+    uint8_t exception_info;
+    uint8_t instruction_byte_count;
+    uint32_t error_code;
+    uint64_t exception_parameter; /* DR6 for #DB, CR2 for #PF */
+    uint64_t reserved;
+    uint8_t instruction_bytes[16];
+    struct hv_x64_segment_register ds_segment;
+    struct hv_x64_segment_register ss_segment;
+    uint64_t rax;
+    uint64_t rcx;
+    uint64_t rdx;
+    uint64_t rbx;
+    uint64_t rsp;
+    uint64_t rbp;
+    uint64_t rsi;
+    uint64_t rdi;
+    uint64_t r8;
+    uint64_t r9;
+    uint64_t r10;
+    uint64_t r11;
+    uint64_t r12;
+    uint64_t r13;
+    uint64_t r14;
+    uint64_t r15;
+} QEMU_PACKED;
+
 union hv_message_flags {
     uint8_t asu8;
     struct {
@@ -943,6 +998,7 @@ struct hv_cpuid {
 
 #define HVCALL_GET_PARTITION_PROPERTY    0x0044
 #define HVCALL_SET_PARTITION_PROPERTY    0x0045
+#define HVCALL_INSTALL_INTERCEPT         0x004d
 #define HVCALL_GET_VP_REGISTERS          0x0050
 #define HVCALL_SET_VP_REGISTERS          0x0051
 #define HVCALL_TRANSLATE_VIRTUAL_ADDRESS 0x0052
-- 
2.53.0