2 * Kernel-based Virtual Machine driver for Linux
4 * derived from drivers/kvm/kvm_main.c
6 * Copyright (C) 2006 Qumranet, Inc.
9 * Avi Kivity <avi@qumranet.com>
10 * Yaniv Kamay <yaniv@qumranet.com>
12 * This work is licensed under the terms of the GNU GPL, version 2. See
13 * the COPYING file in the top-level directory.
21 #include <linux/kvm.h>
23 #include <linux/vmalloc.h>
25 #include <asm/uaccess.h>
27 #define MAX_IO_MSRS 256
30 * List of msr numbers which we expose to userspace through KVM_GET_MSRS
31 * and KVM_SET_MSRS, and KVM_GET_MSR_INDEX_LIST.
33 * This list is modified at module load time to reflect the
34 * capabilities of the host cpu.
36 static u32 msrs_to_save[] = {
37 MSR_IA32_SYSENTER_CS, MSR_IA32_SYSENTER_ESP, MSR_IA32_SYSENTER_EIP,
40 MSR_CSTAR, MSR_KERNEL_GS_BASE, MSR_SYSCALL_MASK, MSR_LSTAR,
42 MSR_IA32_TIME_STAMP_COUNTER,
45 static unsigned num_msrs_to_save;
47 static u32 emulated_msrs[] = {
52 * Adapt set_msr() to msr_io()'s calling convention
54 static int do_set_msr(struct kvm_vcpu *vcpu, unsigned index, u64 *data)
56 return kvm_set_msr(vcpu, index, *data);
60 * Read or write a bunch of msrs. All parameters are kernel addresses.
62 * @return number of msrs set successfully.
64 static int __msr_io(struct kvm_vcpu *vcpu, struct kvm_msrs *msrs,
65 struct kvm_msr_entry *entries,
66 int (*do_msr)(struct kvm_vcpu *vcpu,
67 unsigned index, u64 *data))
73 for (i = 0; i < msrs->nmsrs; ++i)
74 if (do_msr(vcpu, entries[i].index, &entries[i].data))
83 * Read or write a bunch of msrs. Parameters are user addresses.
85 * @return number of msrs set successfully.
87 static int msr_io(struct kvm_vcpu *vcpu, struct kvm_msrs __user *user_msrs,
88 int (*do_msr)(struct kvm_vcpu *vcpu,
89 unsigned index, u64 *data),
93 struct kvm_msr_entry *entries;
98 if (copy_from_user(&msrs, user_msrs, sizeof msrs))
102 if (msrs.nmsrs >= MAX_IO_MSRS)
106 size = sizeof(struct kvm_msr_entry) * msrs.nmsrs;
107 entries = vmalloc(size);
112 if (copy_from_user(entries, user_msrs->entries, size))
115 r = n = __msr_io(vcpu, &msrs, entries, do_msr);
120 if (writeback && copy_to_user(user_msrs->entries, entries, size))
131 long kvm_arch_dev_ioctl(struct file *filp,
132 unsigned int ioctl, unsigned long arg)
134 void __user *argp = (void __user *)arg;
138 case KVM_GET_MSR_INDEX_LIST: {
139 struct kvm_msr_list __user *user_msr_list = argp;
140 struct kvm_msr_list msr_list;
144 if (copy_from_user(&msr_list, user_msr_list, sizeof msr_list))
147 msr_list.nmsrs = num_msrs_to_save + ARRAY_SIZE(emulated_msrs);
148 if (copy_to_user(user_msr_list, &msr_list, sizeof msr_list))
151 if (n < num_msrs_to_save)
154 if (copy_to_user(user_msr_list->indices, &msrs_to_save,
155 num_msrs_to_save * sizeof(u32)))
157 if (copy_to_user(user_msr_list->indices
158 + num_msrs_to_save * sizeof(u32),
160 ARRAY_SIZE(emulated_msrs) * sizeof(u32)))
172 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
174 kvm_x86_ops->vcpu_load(vcpu, cpu);
177 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
179 kvm_x86_ops->vcpu_put(vcpu);
182 static void cpuid_fix_nx_cap(struct kvm_vcpu *vcpu)
186 struct kvm_cpuid_entry *e, *entry;
188 rdmsrl(MSR_EFER, efer);
190 for (i = 0; i < vcpu->cpuid_nent; ++i) {
191 e = &vcpu->cpuid_entries[i];
192 if (e->function == 0x80000001) {
197 if (entry && (entry->edx & (1 << 20)) && !(efer & EFER_NX)) {
198 entry->edx &= ~(1 << 20);
199 printk(KERN_INFO "kvm: guest NX capability removed\n");
203 static int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
204 struct kvm_cpuid *cpuid,
205 struct kvm_cpuid_entry __user *entries)
210 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
213 if (copy_from_user(&vcpu->cpuid_entries, entries,
214 cpuid->nent * sizeof(struct kvm_cpuid_entry)))
216 vcpu->cpuid_nent = cpuid->nent;
217 cpuid_fix_nx_cap(vcpu);
224 static int kvm_vcpu_ioctl_get_lapic(struct kvm_vcpu *vcpu,
225 struct kvm_lapic_state *s)
228 memcpy(s->regs, vcpu->apic->regs, sizeof *s);
234 static int kvm_vcpu_ioctl_set_lapic(struct kvm_vcpu *vcpu,
235 struct kvm_lapic_state *s)
238 memcpy(vcpu->apic->regs, s->regs, sizeof *s);
239 kvm_apic_post_state_restore(vcpu);
245 long kvm_arch_vcpu_ioctl(struct file *filp,
246 unsigned int ioctl, unsigned long arg)
248 struct kvm_vcpu *vcpu = filp->private_data;
249 void __user *argp = (void __user *)arg;
253 case KVM_GET_LAPIC: {
254 struct kvm_lapic_state lapic;
256 memset(&lapic, 0, sizeof lapic);
257 r = kvm_vcpu_ioctl_get_lapic(vcpu, &lapic);
261 if (copy_to_user(argp, &lapic, sizeof lapic))
266 case KVM_SET_LAPIC: {
267 struct kvm_lapic_state lapic;
270 if (copy_from_user(&lapic, argp, sizeof lapic))
272 r = kvm_vcpu_ioctl_set_lapic(vcpu, &lapic);;
278 case KVM_SET_CPUID: {
279 struct kvm_cpuid __user *cpuid_arg = argp;
280 struct kvm_cpuid cpuid;
283 if (copy_from_user(&cpuid, cpuid_arg, sizeof cpuid))
285 r = kvm_vcpu_ioctl_set_cpuid(vcpu, &cpuid, cpuid_arg->entries);
291 r = msr_io(vcpu, argp, kvm_get_msr, 1);
294 r = msr_io(vcpu, argp, do_set_msr, 0);
303 static __init void kvm_init_msr_list(void)
308 for (i = j = 0; i < ARRAY_SIZE(msrs_to_save); i++) {
309 if (rdmsr_safe(msrs_to_save[i], &dummy[0], &dummy[1]) < 0)
312 msrs_to_save[j] = msrs_to_save[i];
315 num_msrs_to_save = j;
318 __init void kvm_arch_init(void)