Implement API to inject virtual interrupts into VMs.
This doesn't yet work properly in multiple-PE configurations, and doesn't have
any concept of priorities.
Bug: 117270899
Change-Id: Id62c59d78d0604b934aeca75ea459248db660488
diff --git a/inc/hf/api.h b/inc/hf/api.h
index 5359f86..692fbac 100644
--- a/inc/hf/api.h
+++ b/inc/hf/api.h
@@ -38,3 +38,9 @@
struct vcpu *api_wait_for_interrupt(struct vcpu *current);
struct vcpu *api_yield(struct vcpu *current);
+
+int64_t api_enable_interrupt(uint32_t intid, bool enable, struct vcpu *current);
+uint32_t api_get_and_acknowledge_interrupt(struct vcpu *current);
+int64_t api_inject_interrupt(uint32_t target_vm_id, uint32_t target_vcpu_idx,
+ uint32_t intid, struct vcpu *current,
+ struct vcpu **next);
diff --git a/inc/hf/cpu.h b/inc/hf/cpu.h
index 60261fe..d2029dd 100644
--- a/inc/hf/cpu.h
+++ b/inc/hf/cpu.h
@@ -25,6 +25,11 @@
#include "hf/addr.h"
#include "hf/spinlock.h"
+#include "vmapi/hf/types.h"
+
+/** The number of bits in each element of the interrupt bitfields. */
+#define INTERRUPT_REGISTER_BITS 32
+
enum vcpu_state {
/** The vcpu is switched off. */
vcpu_state_off,
@@ -42,6 +47,13 @@
vcpu_state_blocked_interrupt,
};
+struct interrupts {
+ /** Bitfield keeping track of which interrupts are enabled. */
+ uint32_t interrupt_enabled[HF_NUM_INTIDS / INTERRUPT_REGISTER_BITS];
+ /** Bitfield keeping track of which interrupts are pending. */
+ uint32_t interrupt_pending[HF_NUM_INTIDS / INTERRUPT_REGISTER_BITS];
+};
+
struct vcpu {
struct spinlock lock;
enum vcpu_state state;
@@ -49,6 +61,7 @@
struct vm *vm;
struct vcpu *mailbox_next;
struct arch_regs regs;
+ struct interrupts interrupts;
};
/* TODO: Update alignment such that cpus are in different cache lines. */
diff --git a/inc/hf/std.h b/inc/hf/std.h
index 55922fa..39d3d08 100644
--- a/inc/hf/std.h
+++ b/inc/hf/std.h
@@ -27,6 +27,8 @@
size_t strlen(const char *str);
int strcmp(const char *a, const char *b);
+#define ctz(x) __builtin_ctz(x)
+
#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
#define be16toh(v) __builtin_bswap16(v)
diff --git a/inc/vmapi/hf/call.h b/inc/vmapi/hf/call.h
index 102fd6c..7de8160 100644
--- a/inc/vmapi/hf/call.h
+++ b/inc/vmapi/hf/call.h
@@ -16,6 +16,8 @@
#pragma once
+#include "hf/arch/cpu.h"
+
#include "hf/abi.h"
#include "hf/types.h"
@@ -23,13 +25,16 @@
/* clang-format off */
/* TODO: Define constants below according to spec. */
-#define HF_VCPU_RUN 0xff00
-#define HF_VM_GET_COUNT 0xff01
-#define HF_VCPU_GET_COUNT 0xff02
-#define HF_VM_CONFIGURE 0xff03
-#define HF_MAILBOX_SEND 0xff04
-#define HF_MAILBOX_RECEIVE 0xff05
-#define HF_MAILBOX_CLEAR 0xff06
+#define HF_VCPU_RUN 0xff00
+#define HF_VM_GET_COUNT 0xff01
+#define HF_VCPU_GET_COUNT 0xff02
+#define HF_VM_CONFIGURE 0xff03
+#define HF_MAILBOX_SEND 0xff04
+#define HF_MAILBOX_RECEIVE 0xff05
+#define HF_MAILBOX_CLEAR 0xff06
+#define HF_ENABLE_INTERRUPT 0xff07
+#define HF_GET_AND_ACKNOWLEDGE_INTERRUPT 0xff08
+#define HF_INJECT_INTERRUPT 0xff09
/** The amount of data that can be sent to a mailbox. */
#define HF_MAILBOX_SIZE 4096
@@ -118,3 +123,39 @@
{
return hf_call(HF_MAILBOX_CLEAR, 0, 0, 0);
}
+
+/**
+ * Enables or disables a given interrupt ID.
+ *
+ * Returns 0 on success, or -1 if the intid is invalid.
+ */
+static inline uint64_t hf_enable_interrupt(uint32_t intid, bool enable)
+{
+ return hf_call(HF_ENABLE_INTERRUPT, intid, enable, 0);
+}
+
+/**
+ * Gets the ID of the pending interrupt (if any) and acknowledge it.
+ *
+ * Returns HF_INVALID_INTID if there are no pending interrupts.
+ */
+static inline uint32_t hf_get_and_acknowledge_interrupt()
+{
+ return hf_call(HF_GET_AND_ACKNOWLEDGE_INTERRUPT, 0, 0, 0);
+}
+
+/**
+ * Injects a virtual interrupt of the given ID into the given target vCPU.
+ * This doesn't cause the vCPU to actually be run immediately; it will be taken
+ * when the vCPU is next run, which is up to the scheduler.
+ *
+ * Returns 0 on success, or -1 if the target VM or vCPU doesn't exist or
+ * the interrupt ID is invalid.
+ */
+static inline int64_t hf_inject_interrupt(uint32_t target_vm_id,
+ uint32_t target_vcpu_idx,
+ uint32_t intid)
+{
+ return hf_call(HF_INJECT_INTERRUPT, target_vm_id, target_vcpu_idx,
+ intid);
+}
diff --git a/inc/vmapi/hf/types.h b/inc/vmapi/hf/types.h
index 45aa257..697a990 100644
--- a/inc/vmapi/hf/types.h
+++ b/inc/vmapi/hf/types.h
@@ -39,3 +39,9 @@
/* Invalid values for fields to indicate absence or errors. */
#define HF_INVALID_VM_ID 0xffffffff
#define HF_INVALID_VCPU 0xffff
+
+/** The number of virtual interrupt IDs which are supported. */
+#define HF_NUM_INTIDS 64
+
+/** Interrupt ID returned when there is no interrupt pending. */
+#define HF_INVALID_INTID 0xffffffff