KVM: x86/xen: register shared_info page

Add KVM_XEN_ATTR_TYPE_SHARED_INFO to allow hypervisor to know where the
guest's shared info page is.

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
This commit is contained in:
Joao Martins 2018-06-15 21:17:14 -04:00 committed by David Woodhouse
parent 1ea9f2ed81
commit 13ffb97a3b
3 changed files with 43 additions and 5 deletions

View File

@ -908,6 +908,8 @@ struct msr_bitmap_range {
/* Xen emulation context */ /* Xen emulation context */
struct kvm_xen { struct kvm_xen {
bool long_mode; bool long_mode;
bool shinfo_set;
struct gfn_to_hva_cache shinfo_cache;
}; };
enum kvm_irqchip_mode { enum kvm_irqchip_mode {

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@ -13,25 +13,49 @@
#include <linux/kvm_host.h> #include <linux/kvm_host.h>
#include <trace/events/kvm.h> #include <trace/events/kvm.h>
#include <xen/interface/xen.h>
#include "trace.h" #include "trace.h"
DEFINE_STATIC_KEY_DEFERRED_FALSE(kvm_xen_enabled, HZ); DEFINE_STATIC_KEY_DEFERRED_FALSE(kvm_xen_enabled, HZ);
static int kvm_xen_shared_info_init(struct kvm *kvm, gfn_t gfn)
{
int ret;
int idx = srcu_read_lock(&kvm->srcu);
ret = kvm_gfn_to_hva_cache_init(kvm, &kvm->arch.xen.shinfo_cache,
gfn_to_gpa(gfn), PAGE_SIZE);
if (!ret) {
kvm->arch.xen.shinfo_set = true;
}
srcu_read_unlock(&kvm->srcu, idx);
return ret;
}
int kvm_xen_hvm_set_attr(struct kvm *kvm, struct kvm_xen_hvm_attr *data) int kvm_xen_hvm_set_attr(struct kvm *kvm, struct kvm_xen_hvm_attr *data)
{ {
int r = -ENOENT; int r = -ENOENT;
mutex_lock(&kvm->lock);
mutex_unlock(&kvm->lock); mutex_unlock(&kvm->lock);
switch (data->type) { switch (data->type) {
case KVM_XEN_ATTR_TYPE_LONG_MODE: case KVM_XEN_ATTR_TYPE_LONG_MODE:
if (!IS_ENABLED(CONFIG_64BIT) && data->u.long_mode) if (!IS_ENABLED(CONFIG_64BIT) && data->u.long_mode) {
return -EINVAL; r = -EINVAL;
} else {
kvm->arch.xen.long_mode = !!data->u.long_mode; kvm->arch.xen.long_mode = !!data->u.long_mode;
r = 0; r = 0;
}
break; break;
case KVM_XEN_ATTR_TYPE_SHARED_INFO:
r = kvm_xen_shared_info_init(kvm, data->u.shared_info.gfn);
break;
default: default:
break; break;
} }
@ -51,6 +75,14 @@ int kvm_xen_hvm_get_attr(struct kvm *kvm, struct kvm_xen_hvm_attr *data)
data->u.long_mode = kvm->arch.xen.long_mode; data->u.long_mode = kvm->arch.xen.long_mode;
r = 0; r = 0;
break; break;
case KVM_XEN_ATTR_TYPE_SHARED_INFO:
if (kvm->arch.xen.shinfo_set) {
data->u.shared_info.gfn = gpa_to_gfn(kvm->arch.xen.shinfo_cache.gpa);
r = 0;
}
break;
default: default:
break; break;
} }

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@ -1595,11 +1595,15 @@ struct kvm_xen_hvm_attr {
__u16 pad[3]; __u16 pad[3];
union { union {
__u8 long_mode; __u8 long_mode;
struct {
__u64 gfn;
} shared_info;
__u64 pad[8]; __u64 pad[8];
} u; } u;
}; };
#define KVM_XEN_ATTR_TYPE_LONG_MODE 0x0 #define KVM_XEN_ATTR_TYPE_LONG_MODE 0x0
#define KVM_XEN_ATTR_TYPE_SHARED_INFO 0x1
/* Secure Encrypted Virtualization command */ /* Secure Encrypted Virtualization command */
enum sev_cmd_id { enum sev_cmd_id {