From 7ba1e61953f4592606e60b2e7507ff6a6faf861a Mon Sep 17 00:00:00 2001 From: aliguori Date: Wed, 5 Nov 2008 16:04:33 +0000 Subject: Add KVM support to QEMU This patch adds very basic KVM support. KVM is a kernel module for Linux that allows userspace programs to make use of hardware virtualization support. It current supports x86 hardware virtualization using Intel VT-x or AMD-V. It also supports IA64 VT-i, PPC 440, and S390. This patch only implements the bare minimum support to get a guest booting. It has very little impact the rest of QEMU and attempts to integrate nicely with the rest of QEMU. Even though this implementation is basic, it is significantly faster than TCG. Booting and shutting down a Linux guest: w/TCG: 1:32.36 elapsed 84% CPU w/KVM: 0:31.14 elapsed 59% CPU Right now, KVM is disabled by default and must be explicitly enabled with -enable-kvm. We can enable it by default later when we have had better testing. Signed-off-by: Anthony Liguori git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5627 c046a42c-6fe2-441c-8c8c-71466251a162 --- target-i386/helper.c | 73 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 73 insertions(+) (limited to 'target-i386/helper.c') diff --git a/target-i386/helper.c b/target-i386/helper.c index bcf5e7f70..4b8c50379 100644 --- a/target-i386/helper.c +++ b/target-i386/helper.c @@ -29,6 +29,7 @@ #include "exec-all.h" #include "svm.h" #include "qemu-common.h" +#include "kvm.h" //#define DEBUG_MMU @@ -115,6 +116,8 @@ CPUX86State *cpu_x86_init(const char *cpu_model) #ifdef USE_KQEMU kqemu_init(env); #endif + if (kvm_enabled()) + kvm_init_vcpu(env); return env; } @@ -1288,6 +1291,40 @@ target_phys_addr_t cpu_get_phys_page_debug(CPUState *env, target_ulong addr) } #endif /* !CONFIG_USER_ONLY */ +#if defined(CONFIG_KVM) +static void host_cpuid(uint32_t function, uint32_t *eax, uint32_t *ebx, + uint32_t *ecx, uint32_t *edx) +{ + uint32_t vec[4]; + +#ifdef __x86_64__ + asm volatile("cpuid" + : "=a"(vec[0]), "=b"(vec[1]), + "=c"(vec[2]), "=d"(vec[3]) + : "0"(function) : "cc"); +#else + asm volatile("pusha \n\t" + "cpuid \n\t" + "mov %%eax, 0(%1) \n\t" + "mov %%ebx, 4(%1) \n\t" + "mov %%ecx, 8(%1) \n\t" + "mov %%edx, 12(%1) \n\t" + "popa" + : : "a"(function), "S"(vec) + : "memory", "cc"); +#endif + + if (eax) + *eax = vec[0]; + if (ebx) + *ebx = vec[1]; + if (ecx) + *ecx = vec[2]; + if (edx) + *edx = vec[3]; +} +#endif + void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t *eax, uint32_t *ebx, uint32_t *ecx, uint32_t *edx) @@ -1307,12 +1344,23 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, *ebx = env->cpuid_vendor1; *edx = env->cpuid_vendor2; *ecx = env->cpuid_vendor3; + + /* sysenter isn't supported on compatibility mode on AMD. and syscall + * isn't supported in compatibility mode on Intel. so advertise the + * actuall cpu, and say goodbye to migration between different vendors + * is you use compatibility mode. */ + if (kvm_enabled()) + host_cpuid(0, NULL, ebx, ecx, edx); break; case 1: *eax = env->cpuid_version; *ebx = (env->cpuid_apic_id << 24) | 8 << 8; /* CLFLUSH size in quad words, Linux wants it. */ *ecx = env->cpuid_ext_features; *edx = env->cpuid_features; + + /* "Hypervisor present" bit required for Microsoft SVVP */ + if (kvm_enabled()) + *ecx |= (1 << 31); break; case 2: /* cache info: needed for Pentium Pro compatibility */ @@ -1390,6 +1438,31 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, *ebx = 0; *ecx = env->cpuid_ext3_features; *edx = env->cpuid_ext2_features; + + if (kvm_enabled()) { + uint32_t h_eax, h_edx; + + host_cpuid(0x80000001, &h_eax, NULL, NULL, &h_edx); + + /* disable CPU features that the host does not support */ + + /* long mode */ + if ((h_edx & 0x20000000) == 0 /* || !lm_capable_kernel */) + *edx &= ~0x20000000; + /* syscall */ + if ((h_edx & 0x00000800) == 0) + *edx &= ~0x00000800; + /* nx */ + if ((h_edx & 0x00100000) == 0) + *edx &= ~0x00100000; + + /* disable CPU features that KVM cannot support */ + + /* svm */ + *ecx &= ~4UL; + /* 3dnow */ + *edx = ~0xc0000000; + } break; case 0x80000002: case 0x80000003: -- cgit v1.2.3