共计 4534 个字符，预计需要花费 12 分钟才能阅读完成。
这篇文章将为大家详细讲解有关 KVM based VM example cpde 的示例代码，丸趣 TV 小编觉得挺实用的，因此分享给大家做个参考，希望大家阅读完这篇文章后可以有所收获。
/* Sample code for /dev/kvm API
*
* Copyright (c) 2015 Intel Corporation
* Author: Josh Triplett josh@joshtriplett.org
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the Software), to
* deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED AS IS , WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*/
#include err.h
#include fcntl.h
#include linux/kvm.h
#include stdint.h
#include stdio.h
#include stdlib.h
#include string.h
#include sys/ioctl.h
#include sys/mman.h
#include sys/stat.h
#include sys/types.h
int main(void)
int kvm, vmfd, vcpufd, ret;
const uint8_t code[] = {
0xba, 0xf8, 0x03, /* mov $0x3f8, %dx */
0x00, 0xd8, /* add %bl, %al */
0x04, 0 , /* add $ 0 , %al */
0xee, /* out %al, (%dx) */
0xb0, \n , /* mov $ \n , %al */
0xee, /* out %al, (%dx) */
0xf4, /* hlt */
};
uint8_t *mem;
struct kvm_sregs sregs;
size_t mmap_size;
struct kvm_run *run;
kvm = open(/dev/kvm , O_RDWR | O_CLOEXEC);
if (kvm == -1)
err(1, /dev/kvm
/* Make sure we have the stable version of the API */
ret = ioctl(kvm, KVM_GET_API_VERSION, NULL);
if (ret == -1)
err(1, KVM_GET_API_VERSION
if (ret != 12)
errx(1, KVM_GET_API_VERSION %d, expected 12 , ret);
vmfd = ioctl(kvm, KVM_CREATE_VM, (unsigned long)0);
if (vmfd == -1)
err(1, KVM_CREATE_VM
/* Allocate one aligned page of guest memory to hold the code. */
mem = mmap(NULL, 0x1000, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, -1, 0);
if (!mem)
err(1, allocating guest memory
memcpy(mem, code, sizeof(code));
/* Map it to the second page frame (to avoid the real-mode IDT at 0). */
struct kvm_userspace_memory_region region = {
.slot = 0,
.guest_phys_addr = 0x1000,
.memory_size = 0x1000,
.userspace_addr = (uint64_t)mem,
};
ret = ioctl(vmfd, KVM_SET_USER_MEMORY_REGION, region);
if (ret == -1)
err(1, KVM_SET_USER_MEMORY_REGION
vcpufd = ioctl(vmfd, KVM_CREATE_VCPU, (unsigned long)0);
if (vcpufd == -1)
err(1, KVM_CREATE_VCPU
/* Map the shared kvm_run structure and following data. */
ret = ioctl(kvm, KVM_GET_VCPU_MMAP_SIZE, NULL);
if (ret == -1)
err(1, KVM_GET_VCPU_MMAP_SIZE
mmap_size = ret;
if (mmap_size sizeof(*run))
errx(1, KVM_GET_VCPU_MMAP_SIZE unexpectedly small
run = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED, vcpufd, 0);
if (!run)
err(1, mmap vcpu
/* Initialize CS to point at 0, via a read-modify-write of sregs. */
ret = ioctl(vcpufd, KVM_GET_SREGS, sregs);
if (ret == -1)
err(1, KVM_GET_SREGS
sregs.cs.base = 0;
sregs.cs.selector = 0;
ret = ioctl(vcpufd, KVM_SET_SREGS, sregs);
if (ret == -1)
err(1, KVM_SET_SREGS
/* Initialize registers: instruction pointer for our code, addends, and
* initial flags required by x86 architecture. */
struct kvm_regs regs = {
.rip = 0x1000,
.rax = 2,
.rbx = 2,
.rflags = 0x2,
};
ret = ioctl(vcpufd, KVM_SET_REGS, regs);
if (ret == -1)
err(1, KVM_SET_REGS
/* Repeatedly run code and handle VM exits. */
while (1) { ret = ioctl(vcpufd, KVM_RUN, NULL);
if (ret == -1)
err(1, KVM_RUN
switch (run- exit_reason) {
case KVM_EXIT_HLT:
puts( KVM_EXIT_HLT
return 0;
case KVM_EXIT_IO:
if (run- io.direction == KVM_EXIT_IO_OUT run- io.size == 1 run- io.port == 0x3f8 run- io.count == 1)
putchar(*(((char *)run) + run- io.data_offset));
else
errx(1, unhandled KVM_EXIT_IO
break;
case KVM_EXIT_FAIL_ENTRY:
errx(1, KVM_EXIT_FAIL_ENTRY: hardware_entry_failure_reason = 0x%llx ,
(unsigned long long)run- fail_entry.hardware_entry_failure_reason);
case KVM_EXIT_INTERNAL_ERROR:
errx(1, KVM_EXIT_INTERNAL_ERROR: suberror = 0x%x , run- internal.suberror);
default:
errx(1, exit_reason = 0x%x , run- exit_reason);
}
}
}关于“KVM based VM example cpde 的示例代码”这篇文章就分享到这里了，希望以上内容可以对大家有一定的帮助，使各位可以学到更多知识，如果觉得文章不错，请把它分享出去让更多的人看到。
正文完
