5 files changed, 252 insertions, 2 deletions

diff --git a/Documentation/kvm/api.txt b/Documentation/kvm/api.txt
index 159b4efe1b0e..ffba03f55bdf 100644
--- a/Documentation/kvm/api.txt
+++ b/Documentation/kvm/api.txt
@@ -922,6 +922,80 @@ Define which vcpu is the Bootstrap Processor (BSP).  Values are the same
 as the vcpu id in KVM_CREATE_VCPU.  If this ioctl is not called, the default
 is vcpu 0.
 
+4.41 KVM_GET_XSAVE
+
+Capability: KVM_CAP_XSAVE
+Architectures: x86
+Type: vcpu ioctl
+Parameters: struct kvm_xsave (out)
+Returns: 0 on success, -1 on error
+
+struct kvm_xsave {
+        __u32 region[1024];
+};
+
+This ioctl would copy current vcpu's xsave struct to the userspace.
+
+4.42 KVM_SET_XSAVE
+
+Capability: KVM_CAP_XSAVE
+Architectures: x86
+Type: vcpu ioctl
+Parameters: struct kvm_xsave (in)
+Returns: 0 on success, -1 on error
+
+struct kvm_xsave {
+        __u32 region[1024];
+};
+
+This ioctl would copy userspace's xsave struct to the kernel.
+
+4.43 KVM_GET_XCRS
+
+Capability: KVM_CAP_XCRS
+Architectures: x86
+Type: vcpu ioctl
+Parameters: struct kvm_xcrs (out)
+Returns: 0 on success, -1 on error
+
+struct kvm_xcr {
+        __u32 xcr;
+        __u32 reserved;
+        __u64 value;
+};
+
+struct kvm_xcrs {
+        __u32 nr_xcrs;
+        __u32 flags;
+        struct kvm_xcr xcrs[KVM_MAX_XCRS];
+        __u64 padding[16];
+};
+
+This ioctl would copy current vcpu's xcrs to the userspace.
+
+4.44 KVM_SET_XCRS
+
+Capability: KVM_CAP_XCRS
+Architectures: x86
+Type: vcpu ioctl
+Parameters: struct kvm_xcrs (in)
+Returns: 0 on success, -1 on error
+
+struct kvm_xcr {
+        __u32 xcr;
+        __u32 reserved;
+        __u64 value;
+};
+
+struct kvm_xcrs {
+        __u32 nr_xcrs;
+        __u32 flags;
+        struct kvm_xcr xcrs[KVM_MAX_XCRS];
+        __u64 padding[16];
+};
+
+This ioctl would set vcpu's xcr to the value userspace specified.
+
 5. The kvm_run structure
 
 Application code obtains a pointer to the kvm_run structure by
diff --git a/arch/x86/include/asm/kvm.h b/arch/x86/include/asm/kvm.h
index ff90055c7f0b..4d8dcbdfc120 100644
--- a/arch/x86/include/asm/kvm.h
+++ b/arch/x86/include/asm/kvm.h
@@ -22,6 +22,8 @@
 #define __KVM_HAVE_XEN_HVM
 #define __KVM_HAVE_VCPU_EVENTS
 #define __KVM_HAVE_DEBUGREGS
+#define __KVM_HAVE_XSAVE
+#define __KVM_HAVE_XCRS
 
 /* Architectural interrupt line count. */
 #define KVM_NR_INTERRUPTS 256
@@ -299,4 +301,24 @@ struct kvm_debugregs {
         __u64 reserved[9];
 };
 
+/* for KVM_CAP_XSAVE */
+struct kvm_xsave {
+        __u32 region[1024];
+};
+
+#define KVM_MAX_XCRS    16
+
+struct kvm_xcr {
+        __u32 xcr;
+        __u32 reserved;
+        __u64 value;
+};
+
+struct kvm_xcrs {
+        __u32 nr_xcrs;
+        __u32 flags;
+        struct kvm_xcr xcrs[KVM_MAX_XCRS];
+        __u64 padding[16];
+};
+
 #endif /* _ASM_X86_KVM_H */
diff --git a/arch/x86/include/asm/xsave.h b/arch/x86/include/asm/xsave.h
index 29ee4e4c64cf..32c36668fa7b 100644
--- a/arch/x86/include/asm/xsave.h
+++ b/arch/x86/include/asm/xsave.h
@@ -13,8 +13,11 @@
 
 #define FXSAVE_SIZE     512
 
-#define XSTATE_YMM_SIZE 256
-#define XSTATE_YMM_OFFSET (512 + 64)
+#define XSAVE_HDR_SIZE      64
+#define XSAVE_HDR_OFFSET    FXSAVE_SIZE
+
+#define XSAVE_YMM_SIZE      256
+#define XSAVE_YMM_OFFSET    (XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET)
 
 /*
  * These are the features that the OS can handle currently.
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 795999e1ac19..0c8dc9614e7d 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1680,6 +1680,7 @@ int kvm_dev_ioctl_check_extension(long ext)
         case KVM_CAP_PCI_SEGMENT:
         case KVM_CAP_DEBUGREGS:
         case KVM_CAP_X86_ROBUST_SINGLESTEP:
+        case KVM_CAP_XSAVE:
                 r = 1;
                 break;
         case KVM_CAP_COALESCED_MMIO:
@@ -1703,6 +1704,9 @@ int kvm_dev_ioctl_check_extension(long ext)
         case KVM_CAP_MCE:
                 r = KVM_MAX_MCE_BANKS;
                 break;
+        case KVM_CAP_XCRS:
+                r = cpu_has_xsave;
+                break;
         default:
                 r = 0;
                 break;
@@ -2355,6 +2359,77 @@ static int kvm_vcpu_ioctl_x86_set_debugregs(struct kvm_vcpu *vcpu,
         return 0;
 }
 
+static void kvm_vcpu_ioctl_x86_get_xsave(struct kvm_vcpu *vcpu,
+                                         struct kvm_xsave *guest_xsave)
+{
+        if (cpu_has_xsave)
+                memcpy(guest_xsave->region,
+                        &vcpu->arch.guest_fpu.state->xsave,
+                        sizeof(struct xsave_struct));
+        else {
+                memcpy(guest_xsave->region,
+                        &vcpu->arch.guest_fpu.state->fxsave,
+                        sizeof(struct i387_fxsave_struct));
+                *(u64 *)&guest_xsave->region[XSAVE_HDR_OFFSET / sizeof(u32)] =
+                        XSTATE_FPSSE;
+        }
+}
+
+static int kvm_vcpu_ioctl_x86_set_xsave(struct kvm_vcpu *vcpu,
+                                        struct kvm_xsave *guest_xsave)
+{
+        u64 xstate_bv =
+                *(u64 *)&guest_xsave->region[XSAVE_HDR_OFFSET / sizeof(u32)];
+
+        if (cpu_has_xsave)
+                memcpy(&vcpu->arch.guest_fpu.state->xsave,
+                        guest_xsave->region, sizeof(struct xsave_struct));
+        else {
+                if (xstate_bv & ~XSTATE_FPSSE)
+                        return -EINVAL;
+                memcpy(&vcpu->arch.guest_fpu.state->fxsave,
+                        guest_xsave->region, sizeof(struct i387_fxsave_struct));
+        }
+        return 0;
+}
+
+static void kvm_vcpu_ioctl_x86_get_xcrs(struct kvm_vcpu *vcpu,
+                                        struct kvm_xcrs *guest_xcrs)
+{
+        if (!cpu_has_xsave) {
+                guest_xcrs->nr_xcrs = 0;
+                return;
+        }
+
+        guest_xcrs->nr_xcrs = 1;
+        guest_xcrs->flags = 0;
+        guest_xcrs->xcrs[0].xcr = XCR_XFEATURE_ENABLED_MASK;
+        guest_xcrs->xcrs[0].value = vcpu->arch.xcr0;
+}
+
+static int kvm_vcpu_ioctl_x86_set_xcrs(struct kvm_vcpu *vcpu,
+                                       struct kvm_xcrs *guest_xcrs)
+{
+        int i, r = 0;
+
+        if (!cpu_has_xsave)
+                return -EINVAL;
+
+        if (guest_xcrs->nr_xcrs > KVM_MAX_XCRS || guest_xcrs->flags)
+                return -EINVAL;
+
+        for (i = 0; i < guest_xcrs->nr_xcrs; i++)
+                /* Only support XCR0 currently */
+                if (guest_xcrs->xcrs[0].xcr == XCR_XFEATURE_ENABLED_MASK) {
+                        r = __kvm_set_xcr(vcpu, XCR_XFEATURE_ENABLED_MASK,
+                                guest_xcrs->xcrs[0].value);
+                        break;
+                }
+        if (r)
+                r = -EINVAL;
+        return r;
+}
+
 long kvm_arch_vcpu_ioctl(struct file *filp,
                          unsigned int ioctl, unsigned long arg)
 {
@@ -2556,6 +2631,70 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
                 r = kvm_vcpu_ioctl_x86_set_debugregs(vcpu, &dbgregs);
                 break;
         }
+        case KVM_GET_XSAVE: {
+                struct kvm_xsave *xsave;
+
+                xsave = kzalloc(sizeof(struct kvm_xsave), GFP_KERNEL);
+                r = -ENOMEM;
+                if (!xsave)
+                        break;
+
+                kvm_vcpu_ioctl_x86_get_xsave(vcpu, xsave);
+
+                r = -EFAULT;
+                if (copy_to_user(argp, xsave, sizeof(struct kvm_xsave)))
+                        break;
+                r = 0;
+                break;
+        }
+        case KVM_SET_XSAVE: {
+                struct kvm_xsave *xsave;
+
+                xsave = kzalloc(sizeof(struct kvm_xsave), GFP_KERNEL);
+                r = -ENOMEM;
+                if (!xsave)
+                        break;
+
+                r = -EFAULT;
+                if (copy_from_user(xsave, argp, sizeof(struct kvm_xsave)))
+                        break;
+
+                r = kvm_vcpu_ioctl_x86_set_xsave(vcpu, xsave);
+                break;
+        }
+        case KVM_GET_XCRS: {
+                struct kvm_xcrs *xcrs;
+
+                xcrs = kzalloc(sizeof(struct kvm_xcrs), GFP_KERNEL);
+                r = -ENOMEM;
+                if (!xcrs)
+                        break;
+
+                kvm_vcpu_ioctl_x86_get_xcrs(vcpu, xcrs);
+
+                r = -EFAULT;
+                if (copy_to_user(argp, xcrs,
+                                 sizeof(struct kvm_xcrs)))
+                        break;
+                r = 0;
+                break;
+        }
+        case KVM_SET_XCRS: {
+                struct kvm_xcrs *xcrs;
+
+                xcrs = kzalloc(sizeof(struct kvm_xcrs), GFP_KERNEL);
+                r = -ENOMEM;
+                if (!xcrs)
+                        break;
+
+                r = -EFAULT;
+                if (copy_from_user(xcrs, argp,
+                                   sizeof(struct kvm_xcrs)))
+                        break;
+
+                r = kvm_vcpu_ioctl_x86_set_xcrs(vcpu, xcrs);
+                break;
+        }
         default:
                 r = -EINVAL;
         }
diff --git a/include/linux/kvm.h b/include/linux/kvm.h
index 23ea02253900..6fd40f540a8e 100644
--- a/include/linux/kvm.h
+++ b/include/linux/kvm.h
@@ -524,6 +524,12 @@ struct kvm_enable_cap {
 #define KVM_CAP_PPC_OSI 52
 #define KVM_CAP_PPC_UNSET_IRQ 53
 #define KVM_CAP_ENABLE_CAP 54
+#ifdef __KVM_HAVE_XSAVE
+#define KVM_CAP_XSAVE 55
+#endif
+#ifdef __KVM_HAVE_XCRS
+#define KVM_CAP_XCRS 56
+#endif
 
 #ifdef KVM_CAP_IRQ_ROUTING
 
@@ -714,6 +720,12 @@ struct kvm_clock_data {
 #define KVM_GET_DEBUGREGS         _IOR(KVMIO,  0xa1, struct kvm_debugregs)
 #define KVM_SET_DEBUGREGS         _IOW(KVMIO,  0xa2, struct kvm_debugregs)
 #define KVM_ENABLE_CAP            _IOW(KVMIO,  0xa3, struct kvm_enable_cap)
+/* Available with KVM_CAP_XSAVE */
+#define KVM_GET_XSAVE             _IOR(KVMIO,  0xa4, struct kvm_xsave)
+#define KVM_SET_XSAVE             _IOW(KVMIO,  0xa5, struct kvm_xsave)
+/* Available with KVM_CAP_XCRS */
+#define KVM_GET_XCRS              _IOR(KVMIO,  0xa6, struct kvm_xcrs)
+#define KVM_SET_XCRS              _IOW(KVMIO,  0xa7, struct kvm_xcrs)
 
 #define KVM_DEV_ASSIGN_ENABLE_IOMMU     (1 << 0)