From: Peter Gonda <[email protected]>

Add GHCB management functionality similar to the ucall management.
Allows for selftest vCPUs to acquire GHCBs for their usage.

Cc: Vishal Annapurve <[email protected]>
Cc: Ackerley Tng <[email protected]>
Cc: Paolo Bonzini <[email protected]>
Cc: Claudio Imbrenda <[email protected]>
Cc: Sean Christopherson <[email protected]>
Cc: Carlos Bilbao <[email protected]>
Cc: Tom Lendacky <[email protected]>
Cc: Michael Roth <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Peter Gonda <[email protected]>
Signed-off-by: Neeraj Upadhyay <[email protected]>
---
 tools/testing/selftests/kvm/include/x86/sev.h |  2 +
 .../testing/selftests/kvm/lib/x86/processor.c |  9 +++
 tools/testing/selftests/kvm/lib/x86/sev.c     | 78 +++++++++++++++++++
 3 files changed, 89 insertions(+)

diff --git a/tools/testing/selftests/kvm/include/x86/sev.h 
b/tools/testing/selftests/kvm/include/x86/sev.h
index 008b4169f5e2..6cda0acd22e4 100644
--- a/tools/testing/selftests/kvm/include/x86/sev.h
+++ b/tools/testing/selftests/kvm/include/x86/sev.h
@@ -46,6 +46,8 @@ static inline bool is_sev_vm(struct kvm_vm *vm)
        return is_sev_es_vm(vm) || vm->type == KVM_X86_SEV_VM;
 }
 
+int ghcb_nr_pages_required(uint64_t page_size);
+
 void sev_vm_launch(struct kvm_vm *vm, uint32_t policy);
 void sev_vm_launch_measure(struct kvm_vm *vm, uint8_t *measurement);
 void sev_vm_launch_finish(struct kvm_vm *vm);
diff --git a/tools/testing/selftests/kvm/lib/x86/processor.c 
b/tools/testing/selftests/kvm/lib/x86/processor.c
index d4c19ac885a9..d72eb96efb7c 100644
--- a/tools/testing/selftests/kvm/lib/x86/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86/processor.c
@@ -651,6 +651,15 @@ void kvm_arch_vm_post_create(struct kvm_vm *vm)
        sync_global_to_guest(vm, guest_tsc_khz);
 }
 
+int kvm_arch_vm_additional_pages_required(struct vm_shape shape, uint64_t 
page_size)
+{
+       if (shape.type == KVM_X86_SEV_ES_VM ||
+           shape.type == KVM_X86_SNP_VM)
+               return  ghcb_nr_pages_required(page_size);
+
+       return 0;
+}
+
 void vcpu_arch_set_entry_point(struct kvm_vcpu *vcpu, void *guest_code)
 {
        struct kvm_regs regs;
diff --git a/tools/testing/selftests/kvm/lib/x86/sev.c 
b/tools/testing/selftests/kvm/lib/x86/sev.c
index c3a9838f4806..c400faa9cc5f 100644
--- a/tools/testing/selftests/kvm/lib/x86/sev.c
+++ b/tools/testing/selftests/kvm/lib/x86/sev.c
@@ -3,6 +3,80 @@
 #include <stdbool.h>
 
 #include "sev.h"
+#include "linux/bitmap.h"
+#include "svm.h"
+#include "svm_util.h"
+
+struct ghcb_entry {
+       struct ghcb ghcb;
+
+       /* Guest physical address of this GHCB. */
+       void *gpa;
+
+       /* Host virtual address of this struct. */
+       struct ghcb_entry *hva;
+};
+
+struct ghcb_header {
+       struct ghcb_entry ghcbs[KVM_MAX_VCPUS];
+       DECLARE_BITMAP(in_use, KVM_MAX_VCPUS);
+};
+
+static struct ghcb_header *ghcb_pool;
+
+int ghcb_nr_pages_required(uint64_t page_size)
+{
+       return align_up(sizeof(struct ghcb_header), page_size) / page_size;
+}
+
+void ghcb_init(struct kvm_vm *vm)
+{
+       struct ghcb_header *hdr;
+       struct ghcb_entry *entry;
+       vm_vaddr_t vaddr;
+       int i;
+
+       vaddr = vm_vaddr_alloc_shared(vm, sizeof(*hdr), KVM_UTIL_MIN_VADDR,
+                                     MEM_REGION_DATA);
+       hdr = (struct ghcb_header *)addr_gva2hva(vm, vaddr);
+       memset(hdr, 0, sizeof(*hdr));
+
+       for (i = 0; i < KVM_MAX_VCPUS; ++i) {
+               entry = &hdr->ghcbs[i];
+               entry->hva = entry;
+               entry->gpa = (void *)addr_hva2gpa(vm, &entry->ghcb);
+       }
+
+       write_guest_global(vm, ghcb_pool, (struct ghcb_header *)vaddr);
+}
+
+static struct ghcb_entry *ghcb_alloc(void)
+{
+       return &ghcb_pool->ghcbs[0];
+       struct ghcb_entry *entry;
+       int i;
+
+       if (!ghcb_pool)
+               goto ucall_failed;
+
+       for (i = 0; i < KVM_MAX_VCPUS; ++i) {
+               if (!test_and_set_bit(i, ghcb_pool->in_use)) {
+                       entry = &ghcb_pool->ghcbs[i];
+                       memset(&entry->ghcb, 0, sizeof(entry->ghcb));
+                       return entry;
+               }
+       }
+
+ucall_failed:
+       return NULL;
+}
+
+static void ghcb_free(struct ghcb_entry *entry)
+{
+       /* Beware, here be pointer arithmetic.  */
+       clear_bit(entry - ghcb_pool->ghcbs, ghcb_pool->in_use);
+}
+
 
 /*
  * sparsebit_next_clear() can return 0 if [x, 2**64-1] are all set, and the
@@ -88,7 +162,11 @@ void sev_vm_launch(struct kvm_vm *vm, uint32_t policy)
        struct kvm_sev_guest_status status;
        int ctr;
 
+       if (is_sev_es_vm(vm))
+               ghcb_init(vm);
+
        vm_sev_ioctl(vm, KVM_SEV_LAUNCH_START, &launch_start);
+
        vm_sev_ioctl(vm, KVM_SEV_GUEST_STATUS, &status);
 
        TEST_ASSERT_EQ(status.policy, policy);
-- 
2.34.1


Reply via email to