Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
[sfrench/cifs-2.6.git] / arch / x86 / kvm / cpuid.c
index 7456f9ad424b4a8c5e2624b5c0f8931a031e2362..06a278b3701d127b7f7096f23091f69891467362 100644 (file)
@@ -54,7 +54,24 @@ static u32 xstate_required_size(u64 xstate_bv, bool compacted)
 
 #define F feature_bit
 
-static int kvm_check_cpuid(struct kvm_vcpu *vcpu)
+static inline struct kvm_cpuid_entry2 *cpuid_entry2_find(
+       struct kvm_cpuid_entry2 *entries, int nent, u32 function, u32 index)
+{
+       struct kvm_cpuid_entry2 *e;
+       int i;
+
+       for (i = 0; i < nent; i++) {
+               e = &entries[i];
+
+               if (e->function == function && (e->index == index ||
+                   !(e->flags & KVM_CPUID_FLAG_SIGNIFCANT_INDEX)))
+                       return e;
+       }
+
+       return NULL;
+}
+
+static int kvm_check_cpuid(struct kvm_cpuid_entry2 *entries, int nent)
 {
        struct kvm_cpuid_entry2 *best;
 
@@ -62,7 +79,7 @@ static int kvm_check_cpuid(struct kvm_vcpu *vcpu)
         * The existing code assumes virtual address is 48-bit or 57-bit in the
         * canonical address checks; exit if it is ever changed.
         */
-       best = kvm_find_cpuid_entry(vcpu, 0x80000008, 0);
+       best = cpuid_entry2_find(entries, nent, 0x80000008, 0);
        if (best) {
                int vaddr_bits = (best->eax & 0xff00) >> 8;
 
@@ -107,6 +124,13 @@ void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu)
                (best->eax & (1 << KVM_FEATURE_PV_UNHALT)))
                best->eax &= ~(1 << KVM_FEATURE_PV_UNHALT);
 
+       /*
+        * save the feature bitmap to avoid cpuid lookup for every PV
+        * operation
+        */
+       if (best)
+               vcpu->arch.pv_cpuid.features = best->eax;
+
        if (!kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT)) {
                best = kvm_find_cpuid_entry(vcpu, 0x1, 0);
                if (best)
@@ -121,8 +145,6 @@ static void kvm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu)
        struct kvm_lapic *apic = vcpu->arch.apic;
        struct kvm_cpuid_entry2 *best;
 
-       kvm_x86_ops.vcpu_after_set_cpuid(vcpu);
-
        best = kvm_find_cpuid_entry(vcpu, 1, 0);
        if (best && apic) {
                if (cpuid_entry_has(best, X86_FEATURE_TSC_DEADLINE_TIMER))
@@ -146,7 +168,9 @@ static void kvm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu)
        kvm_pmu_refresh(vcpu);
        vcpu->arch.cr4_guest_rsvd_bits =
            __cr4_reserved_bits(guest_cpuid_has, vcpu);
-       kvm_x86_ops.update_exception_bitmap(vcpu);
+
+       /* Invoke the vendor callback only after the above state is updated. */
+       kvm_x86_ops.vcpu_after_set_cpuid(vcpu);
 }
 
 static int is_efer_nx(void)
@@ -186,7 +210,6 @@ int cpuid_query_maxphyaddr(struct kvm_vcpu *vcpu)
 not_found:
        return 36;
 }
-EXPORT_SYMBOL_GPL(cpuid_query_maxphyaddr);
 
 /* when an old userspace process fills a new kernel module */
 int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
@@ -194,46 +217,53 @@ int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
                             struct kvm_cpuid_entry __user *entries)
 {
        int r, i;
-       struct kvm_cpuid_entry *cpuid_entries = NULL;
+       struct kvm_cpuid_entry *e = NULL;
+       struct kvm_cpuid_entry2 *e2 = NULL;
 
-       r = -E2BIG;
        if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
-               goto out;
+               return -E2BIG;
+
        if (cpuid->nent) {
-               cpuid_entries = vmemdup_user(entries,
-                                            array_size(sizeof(struct kvm_cpuid_entry),
-                                                       cpuid->nent));
-               if (IS_ERR(cpuid_entries)) {
-                       r = PTR_ERR(cpuid_entries);
-                       goto out;
+               e = vmemdup_user(entries, array_size(sizeof(*e), cpuid->nent));
+               if (IS_ERR(e))
+                       return PTR_ERR(e);
+
+               e2 = kvmalloc_array(cpuid->nent, sizeof(*e2), GFP_KERNEL_ACCOUNT);
+               if (!e2) {
+                       r = -ENOMEM;
+                       goto out_free_cpuid;
                }
        }
        for (i = 0; i < cpuid->nent; i++) {
-               vcpu->arch.cpuid_entries[i].function = cpuid_entries[i].function;
-               vcpu->arch.cpuid_entries[i].eax = cpuid_entries[i].eax;
-               vcpu->arch.cpuid_entries[i].ebx = cpuid_entries[i].ebx;
-               vcpu->arch.cpuid_entries[i].ecx = cpuid_entries[i].ecx;
-               vcpu->arch.cpuid_entries[i].edx = cpuid_entries[i].edx;
-               vcpu->arch.cpuid_entries[i].index = 0;
-               vcpu->arch.cpuid_entries[i].flags = 0;
-               vcpu->arch.cpuid_entries[i].padding[0] = 0;
-               vcpu->arch.cpuid_entries[i].padding[1] = 0;
-               vcpu->arch.cpuid_entries[i].padding[2] = 0;
+               e2[i].function = e[i].function;
+               e2[i].eax = e[i].eax;
+               e2[i].ebx = e[i].ebx;
+               e2[i].ecx = e[i].ecx;
+               e2[i].edx = e[i].edx;
+               e2[i].index = 0;
+               e2[i].flags = 0;
+               e2[i].padding[0] = 0;
+               e2[i].padding[1] = 0;
+               e2[i].padding[2] = 0;
        }
-       vcpu->arch.cpuid_nent = cpuid->nent;
-       r = kvm_check_cpuid(vcpu);
+
+       r = kvm_check_cpuid(e2, cpuid->nent);
        if (r) {
-               vcpu->arch.cpuid_nent = 0;
-               kvfree(cpuid_entries);
-               goto out;
+               kvfree(e2);
+               goto out_free_cpuid;
        }
 
+       kvfree(vcpu->arch.cpuid_entries);
+       vcpu->arch.cpuid_entries = e2;
+       vcpu->arch.cpuid_nent = cpuid->nent;
+
        cpuid_fix_nx_cap(vcpu);
        kvm_update_cpuid_runtime(vcpu);
        kvm_vcpu_after_set_cpuid(vcpu);
 
-       kvfree(cpuid_entries);
-out:
+out_free_cpuid:
+       kvfree(e);
+
        return r;
 }
 
@@ -241,26 +271,32 @@ int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu,
                              struct kvm_cpuid2 *cpuid,
                              struct kvm_cpuid_entry2 __user *entries)
 {
+       struct kvm_cpuid_entry2 *e2 = NULL;
        int r;
 
-       r = -E2BIG;
        if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
-               goto out;
-       r = -EFAULT;
-       if (copy_from_user(&vcpu->arch.cpuid_entries, entries,
-                          cpuid->nent * sizeof(struct kvm_cpuid_entry2)))
-               goto out;
-       vcpu->arch.cpuid_nent = cpuid->nent;
-       r = kvm_check_cpuid(vcpu);
+               return -E2BIG;
+
+       if (cpuid->nent) {
+               e2 = vmemdup_user(entries, array_size(sizeof(*e2), cpuid->nent));
+               if (IS_ERR(e2))
+                       return PTR_ERR(e2);
+       }
+
+       r = kvm_check_cpuid(e2, cpuid->nent);
        if (r) {
-               vcpu->arch.cpuid_nent = 0;
-               goto out;
+               kvfree(e2);
+               return r;
        }
 
+       kvfree(vcpu->arch.cpuid_entries);
+       vcpu->arch.cpuid_entries = e2;
+       vcpu->arch.cpuid_nent = cpuid->nent;
+
        kvm_update_cpuid_runtime(vcpu);
        kvm_vcpu_after_set_cpuid(vcpu);
-out:
-       return r;
+
+       return 0;
 }
 
 int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu,
@@ -941,17 +977,8 @@ out_free:
 struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu,
                                              u32 function, u32 index)
 {
-       struct kvm_cpuid_entry2 *e;
-       int i;
-
-       for (i = 0; i < vcpu->arch.cpuid_nent; ++i) {
-               e = &vcpu->arch.cpuid_entries[i];
-
-               if (e->function == function && (e->index == index ||
-                   !(e->flags & KVM_CPUID_FLAG_SIGNIFCANT_INDEX)))
-                       return e;
-       }
-       return NULL;
+       return cpuid_entry2_find(vcpu->arch.cpuid_entries, vcpu->arch.cpuid_nent,
+                                function, index);
 }
 EXPORT_SYMBOL_GPL(kvm_find_cpuid_entry);