The command initializes the SEV firmware and allocates a new ASID for
this guest from the SEV ASID pool. The firmware must be initialized
before we issue any guest launch commands to create a new memory
encryption context.
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: "Radim Krčmář" <rkrcmar@xxxxxxxxxx>
Cc: Joerg Roedel <joro@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxx>
Cc: Tom Lendacky <thomas.lendacky@xxxxxxx>
Cc: x86@xxxxxxxxxx
Cc: kvm@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Brijesh Singh <brijesh.singh@xxxxxxx>
---
arch/x86/include/asm/kvm_host.h | 7 ++
arch/x86/kvm/svm.c | 184 +++++++++++++++++++++++++++++++++++++++-
2 files changed, 190 insertions(+), 1 deletion(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 20fba8bfa727..6bd49e80a16d 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -747,6 +747,11 @@ enum kvm_irqchip_mode {
KVM_IRQCHIP_SPLIT, /* created with KVM_CAP_SPLIT_IRQCHIP */
};
+struct kvm_sev_info {
+ bool active; /* SEV enabled guest */
+ unsigned int asid; /* ASID used for this guest */
+};
+
struct kvm_arch {
unsigned int n_used_mmu_pages;
unsigned int n_requested_mmu_pages;
@@ -834,6 +839,8 @@ struct kvm_arch {
bool x2apic_format;
bool x2apic_broadcast_quirk_disabled;
+
+ struct kvm_sev_info sev_info;
};
struct kvm_vm_stat {
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 3535aa510194..229bb7d09c44 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -37,6 +37,8 @@
#include <linux/amd-iommu.h>
#include <linux/hashtable.h>
#include <linux/frame.h>
+#include <linux/psp-sev.h>
+#include <linux/file.h>
#include <asm/apic.h>
#include <asm/perf_event.h>
@@ -320,6 +322,19 @@ enum {
#define VMCB_AVIC_APIC_BAR_MASK 0xFFFFFFFFFF000ULL
static unsigned int max_sev_asid;
+static unsigned long *sev_asid_bitmap;
+
+static inline bool svm_sev_enabled(void)
+{
+ return max_sev_asid;
+}
+
+static inline bool sev_guest(struct kvm *kvm)
+{
+ struct kvm_sev_info *sev = &kvm->arch.sev_info;
+
+ return sev->active;
+}
static inline void mark_all_dirty(struct vmcb *vmcb)
{
@@ -1059,6 +1074,11 @@ static int avic_ga_log_notifier(u32 ga_tag)
static __init void sev_hardware_setup(void)
{
max_sev_asid = cpuid_ecx(0x8000001F);
+
+ /* Initialize SEV ASID bitmap */
+ if (max_sev_asid)
+ sev_asid_bitmap = kcalloc(BITS_TO_LONGS(max_sev_asid),
+ sizeof(unsigned long), GFP_KERNEL);
}
static __init int svm_hardware_setup(void)
@@ -1156,10 +1176,45 @@ static __init int svm_hardware_setup(void)
return r;
}
+static int sev_platform_get_state(int *state, int *error)
+{
+ int ret;
+ struct sev_data_status *data;
+
+ data = kzalloc(sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ ret = sev_platform_status(data, error);
+ if (!ret)
+ *state = data->state;
+
+ pr_info_once("SEV firmware major %d minor %d build %d\n",
+ data->api_major, data->api_minor, data->build);
+
+ kfree(data);
+ return ret;
+}
+
+static __exit void sev_hardware_unsetup(void)
+{
+ int state;
+
+ sev_platform_get_state(&state, NULL);
+
+ if (state != SEV_STATE_UNINIT)
+ sev_platform_shutdown(NULL);
+
+ kfree(sev_asid_bitmap);
+}
+
static __exit void svm_hardware_unsetup(void)
{
int cpu;
+ if (svm_sev_enabled())
+ sev_hardware_unsetup();
+
for_each_possible_cpu(cpu)
svm_cpu_uninit(cpu);
@@ -1350,6 +1405,9 @@ static void init_vmcb(struct vcpu_svm *svm)
svm->vmcb->control.int_ctl |= V_GIF_ENABLE_MASK;
}
+ if (sev_guest(svm->vcpu.kvm))
+ svm->vmcb->control.nested_ctl |= SVM_NESTED_CTL_SEV_ENABLE;
+
mark_all_dirty(svm->vmcb);
enable_gif(svm);
@@ -1432,6 +1490,35 @@ static int avic_init_backing_page(struct kvm_vcpu *vcpu)
return 0;
}
+static void sev_firmware_exit(void)
+{
+ int state;
+
+ sev_platform_get_state(&state, NULL);
+
+ if (state == SEV_STATE_INIT)
+ sev_platform_shutdown(NULL);
+}
+
+static void sev_asid_free(struct kvm *kvm)
+{
+ struct kvm_sev_info *sev = &kvm->arch.sev_info;
+ int pos, asid;
+
+ if (svm_sev_enabled())
+ return;
+
+ asid = sev->asid;
+ pos = asid - 1;
+ clear_bit(pos, sev_asid_bitmap);
+}
+
+static void sev_vm_destroy(struct kvm *kvm)
+{
+ sev_asid_free(kvm);
+ sev_firmware_exit();
+}
+
static void avic_vm_destroy(struct kvm *kvm)
{
unsigned long flags;
@@ -1450,6 +1537,14 @@ static void avic_vm_destroy(struct kvm *kvm)
spin_unlock_irqrestore(&svm_vm_data_hash_lock, flags);
}
+static void svm_vm_destroy(struct kvm *kvm)
+{
+ avic_vm_destroy(kvm);
+
+ if (sev_guest(kvm))
+ sev_vm_destroy(kvm);
+}
+
static int avic_vm_init(struct kvm *kvm)
{
unsigned long flags;
@@ -5416,6 +5511,91 @@ static void svm_setup_mce(struct kvm_vcpu *vcpu)
vcpu->arch.mcg_cap &= 0x1ff;
}
+static int sev_asid_new(void)
+{
+ int pos;
+
+ if (!svm_sev_enabled())
+ return -EINVAL;
+
+ pos = find_first_zero_bit(sev_asid_bitmap, max_sev_asid);
+ if (pos >= max_sev_asid)
+ return -EBUSY;
+
+ set_bit(pos, sev_asid_bitmap);
+ return pos + 1;
+}
+
+static int sev_firmware_init(struct kvm *kvm, int *error)
+{
+ int ret, state;
+
+ ret = sev_platform_get_state(&state, error);
+ if (ret)
+ return ret;
+
+ /* If SEV firmware is in uninitialized state, lets initialize it. */
+ if (state == SEV_STATE_UNINIT) {
+ struct sev_data_init *data;
+
+ data = kzalloc(sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ ret = sev_platform_init(data, error);
+ kfree(data);
+ }
+
+ return ret;
+}
+
+static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp)
+{
+ struct kvm_sev_info *sev = &kvm->arch.sev_info;
+ int asid, ret;
+
+ ret = sev_firmware_init(kvm, &argp->error);
+ if (ret)
+ return ret;
+
+ ret = -EBUSY;
+ asid = sev_asid_new();
+ if (asid < 0)
+ goto e_shutdown;
+
+ sev->active = true;
+ sev->asid = asid;
+ return 0;
+e_shutdown:
+ sev_firmware_exit();
+ return ret;
+}
+
+static int svm_mem_enc_op(struct kvm *kvm, void __user *argp)
+{
+ struct kvm_sev_cmd sev_cmd;
+ int r = -ENOTTY;
+
+ if (copy_from_user(&sev_cmd, argp, sizeof(struct kvm_sev_cmd)))
+ return -EFAULT;
+
+ mutex_lock(&kvm->lock);
+
+ switch (sev_cmd.id) {
+ case KVM_SEV_INIT: {
+ r = sev_guest_init(kvm, &sev_cmd);
+ break;
+ }
+ default:
+ break;
+ }
+
+ mutex_unlock(&kvm->lock);
+ if (copy_to_user(argp, &sev_cmd, sizeof(struct kvm_sev_cmd)))
+ r = -EFAULT;
+ return r;
+}
+
static struct kvm_x86_ops svm_x86_ops __ro_after_init = {
.cpu_has_kvm_support = has_svm,
.disabled_by_bios = is_disabled,
@@ -5432,7 +5612,7 @@ static struct kvm_x86_ops svm_x86_ops __ro_after_init = {
.vcpu_reset = svm_vcpu_reset,
.vm_init = avic_vm_init,
- .vm_destroy = avic_vm_destroy,
+ .vm_destroy = svm_vm_destroy,
.prepare_guest_switch = svm_prepare_guest_switch,
.vcpu_load = svm_vcpu_load,
@@ -5526,6 +5706,8 @@ static struct kvm_x86_ops svm_x86_ops __ro_after_init = {
.deliver_posted_interrupt = svm_deliver_avic_intr,
.update_pi_irte = svm_update_pi_irte,
.setup_mce = svm_setup_mce,
+
+ .mem_enc_op = svm_mem_enc_op,
};
static int __init svm_init(void)
--
2.9.5
