Mmap the kvm_run structure

Mmap the kvm_run structure and print out ->exit_reason in human-readable form
upon exit to make it more visible what's happening after KVM_RUN ioctl() is
called.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>

diff --git a/tools/kvm/kvm.c b/tools/kvm/kvm.c
index b63dead3eff71abd44943a9ca23f9ef1cefd6fa1..4a2a04a607e2d9eabc05bb2bcc38535b0a34f584 100644 (file)
--- a/tools/kvm/kvm.c
+++ b/tools/kvm/kvm.c
@@ -1,14 +1,25 @@
 #include "kvm/cpu.h"
 
 #include <linux/kvm.h>
+#include <inttypes.h>
+#include <sys/mman.h>
 #include <stdbool.h>
 #include <stdlib.h>
+#include <stdio.h>
 #include <fcntl.h>
 
+/*
+ * Compatibility code. Remove this when we move to tools/kvm.
+ */
+#ifndef KVM_EXIT_INTERNAL_ERROR
+# define KVM_EXIT_INTERNAL_ERROR               17
+#endif
+
 struct kvm {
        int                     sys_fd;         /* For system ioctls(), i.e. /dev/kvm */
        int                     vm_fd;          /* For VM ioctls() */
        int                     vcpu_fd;        /* For VCPU ioctls() */
+       struct kvm_run          *kvm_run;
 };
 
 static void die(const char *s)
@@ -53,6 +64,7 @@ static struct kvm *kvm__init(void)
 {
        struct kvm_userspace_memory_region mem;
        struct kvm *self;
+       int mmap_size;
        int ret;
 
        self = kvm__new();
@@ -93,6 +105,14 @@ static struct kvm *kvm__init(void)
        if (self->vcpu_fd < 0)
                die("ioctl(KVM_CREATE_VCPU)");
 
+       mmap_size = ioctl(self->sys_fd, KVM_GET_VCPU_MMAP_SIZE, 0);
+       if (mmap_size < 0)
+               die("KVM_GET_VCPU_MMAP_SIZE ioctl() failed");
+
+       self->kvm_run = mmap(NULL, mmap_size, PROT_READ|PROT_WRITE, MAP_SHARED, self->vcpu_fd, 0);
+       if (self->kvm_run == MAP_FAILED)
+               die("unable to mmap vcpu fd");
+
        return self;
 }
 
@@ -105,6 +125,27 @@ static void kvm__run(struct kvm *self)
                die("KVM_RUN");
 }
 
+static const char *exit_reasons[] = {
+       [KVM_EXIT_UNKNOWN]              = "unknown",
+       [KVM_EXIT_EXCEPTION]            = "exception",
+       [KVM_EXIT_IO]                   = "io",
+       [KVM_EXIT_HYPERCALL]            = "hypercall",
+       [KVM_EXIT_DEBUG]                = "debug",
+       [KVM_EXIT_HLT]                  = "hlt",
+       [KVM_EXIT_MMIO]                 = "mmio",
+       [KVM_EXIT_IRQ_WINDOW_OPEN]      = "irq window open",
+       [KVM_EXIT_SHUTDOWN]             = "shutdown",
+       [KVM_EXIT_FAIL_ENTRY]           = "fail entry",
+       [KVM_EXIT_INTR]                 = "intr",
+       [KVM_EXIT_SET_TPR]              = "set tpr",
+       [KVM_EXIT_TPR_ACCESS]           = "trp access",
+       [KVM_EXIT_S390_SIEIC]           = "s390 sieic",
+       [KVM_EXIT_S390_RESET]           = "s390 reset",
+       [KVM_EXIT_DCR]                  = "dcr",
+       [KVM_EXIT_NMI]                  = "dmi",
+       [KVM_EXIT_INTERNAL_ERROR]       = "internal error",
+};
+
 int main(int argc, char *argv[])
 {
        struct cpu *cpu;
@@ -119,5 +160,8 @@ int main(int argc, char *argv[])
 
        kvm__run(kvm);
 
+       fprintf(stderr, "KVM exit reason: %" PRIu32 " (\"%s\")\n",
+               kvm->kvm_run->exit_reason, exit_reasons[kvm->kvm_run->exit_reason]);
+
        return 0;
 }