[RFC,07/13] kvm: Add Mirror VM ioctl and enable cap interfaces.

Commit Message

Kalra, Ashish Aug. 16, 2021, 1:29 p.m. UTC

From: Ashish Kalra <[e-mail]>

Add VM ioctl and enable cap support for Mirror VM's and
a new VM file descriptor for Mirror VM's in KVMState.

The VCPU ioctl interface for Mirror VM works as it is,
as it uses a CPUState and VCPU file descriptor allocated
and setup for mirror vcpus.

Signed-off-by: Ashish Kalra <[e-mail]>
---
 accel/kvm/kvm-all.c  | 23 +++++++++++++++++++++++
 include/sysemu/kvm.h | 14 ++++++++++++++
 2 files changed, 37 insertions(+)

Patch

diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index 0125c17edb..4bc5971881 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -149,6 +149,7 @@  struct KVMState
     uint64_t kvm_dirty_ring_bytes;  /* Size of the per-vcpu dirty ring */
     uint32_t kvm_dirty_ring_size;   /* Number of dirty GFNs per ring */
     struct KVMDirtyRingReaper reaper;
+    int mirror_vm_fd;
 };
 
 KVMState *kvm_state;
@@ -3003,6 +3004,28 @@  int kvm_vm_ioctl(KVMState *s, int type, ...)
     return ret;
 }
 
+int kvm_mirror_vm_ioctl(KVMState *s, int type, ...)
+{
+    int ret;
+    void *arg;
+    va_list ap;
+
+    if (!s->mirror_vm_fd) {
+        return 0;
+    }
+
+    va_start(ap, type);
+    arg = va_arg(ap, void *);
+    va_end(ap);
+
+    trace_kvm_vm_ioctl(type, arg);
+    ret = ioctl(s->mirror_vm_fd, type, arg);
+    if (ret == -1) {
+        ret = -errno;
+    }
+    return ret;
+}
+
 int kvm_vcpu_ioctl(CPUState *cpu, int type, ...)
 {
     int ret;
diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h
index a1ab1ee12d..6847ffcdfd 100644
--- a/include/sysemu/kvm.h
+++ b/include/sysemu/kvm.h
@@ -255,6 +255,8 @@  int kvm_ioctl(KVMState *s, int type, ...);
 
 int kvm_vm_ioctl(KVMState *s, int type, ...);
 
+int kvm_mirror_vm_ioctl(KVMState *s, int type, ...);
+
 int kvm_vcpu_ioctl(CPUState *cpu, int type, ...);
 
 /**
@@ -434,6 +436,18 @@  int kvm_vm_check_extension(KVMState *s, unsigned int extension);
         kvm_vm_ioctl(s, KVM_ENABLE_CAP, &cap);                       \
     })
 
+#define kvm_mirror_vm_enable_cap(s, capability, cap_flags, ...)      \
+    ({                                                               \
+        struct kvm_enable_cap cap = {                                \
+            .cap = capability,                                       \
+            .flags = cap_flags,                                      \
+        };                                                           \
+        uint64_t args_tmp[] = { __VA_ARGS__ };                       \
+        size_t n = MIN(ARRAY_SIZE(args_tmp), ARRAY_SIZE(cap.args));  \
+        memcpy(cap.args, args_tmp, n * sizeof(cap.args[0]));         \
+        kvm_mirror_vm_ioctl(s, KVM_ENABLE_CAP, &cap);                \
+    })
+
 #define kvm_vcpu_enable_cap(cpu, capability, cap_flags, ...)         \
     ({                                                               \
         struct kvm_enable_cap cap = {                                \