SetupEventNotifyInterrupt TDX hypercall is used by guest TD to specify
which interrupt vector to use as an event-notify vector to the VMM.
Such registered vector is also used by Host VMM to notify about
completion of GetQuote requests to the Guest TD.
Add tdx_hcall_set_notify_intr() helper function to implement the
SetupEventNotifyInterrupt hypercall.
This will be used by the TD guest attestation driver.
Details about the SetupEventNotifyInterrupt TDVMCALL can be found in
TDX Guest-Host Communication Interface (GHCI) Specification, sec 3.5
"VP.VMCALL<SetupEventNotifyInterrupt>".
Reviewed-by: Tony Luck <tony.luck@xxxxxxxxx>
Reviewed-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>
---
arch/x86/coco/tdx.c | 33 +++++++++++++++++++++++++++++++++
1 file changed, 33 insertions(+)
diff --git a/arch/x86/coco/tdx.c b/arch/x86/coco/tdx.c
index 2c07f9551d3b..d18508e6150f 100644
--- a/arch/x86/coco/tdx.c
+++ b/arch/x86/coco/tdx.c
@@ -22,6 +22,7 @@
/* TDX hypercall Leaf IDs */
#define TDVMCALL_MAP_GPA 0x10001
#define TDVMCALL_GET_QUOTE 0x10002
+#define TDVMCALL_SETUP_NOTIFY_INTR 0x10004
/* MMIO direction */
#define EPT_READ 0
@@ -175,6 +176,38 @@ int tdx_hcall_get_quote(void *data)
}
EXPORT_SYMBOL_GPL(tdx_hcall_get_quote);
+/*
+ * tdx_hcall_set_notify_intr() - Setup Event Notify Interrupt Vector.
+ *
+ * @vector : Vector address to be used for notification.
+ *
+ * return 0 on success or failure error number.
+ */
+static int tdx_hcall_set_notify_intr(u8 vector)
+{
+ u64 ret;
+
+ /* Minimum vector value allowed is 32 */
+ if (vector < 32)
+ return -EINVAL;
+
+ /*
+ * Register callback vector address with VMM. More details
+ * about the ABI can be found in TDX Guest-Host-Communication
+ * Interface (GHCI), sec titled
+ * "TDG.VP.VMCALL<SetupEventNotifyInterrupt>".
+ */
+ ret = _tdx_hypercall(TDVMCALL_SETUP_NOTIFY_INTR, vector, 0, 0, 0);
+
+ if (ret) {
+ if (ret == TDCALL_INVALID_OPERAND)
+ return -EINVAL;
+ return -EIO;
+ }
+
+ return 0;
+}
+
static void get_info(void)
{
struct tdx_module_output out;
--
2.25.1
