1 files changed, 88 insertions, 0 deletions

diff --git a/arch/s390/kvm/diag.c b/arch/s390/kvm/diag.c
index 6f9cfa500372..08dfc839a6cf 100644
--- a/arch/s390/kvm/diag.c
+++ b/arch/s390/kvm/diag.c
@@ -18,6 +18,7 @@
 #include "kvm-s390.h"
 #include "trace.h"
 #include "trace-s390.h"
+#include "gaccess.h"
 
 static int diag_release_pages(struct kvm_vcpu *vcpu)
 {
@@ -47,6 +48,87 @@ static int diag_release_pages(struct kvm_vcpu *vcpu)
         return 0;
 }
 
+static int __diag_page_ref_service(struct kvm_vcpu *vcpu)
+{
+        struct prs_parm {
+                u16 code;
+                u16 subcode;
+                u16 parm_len;
+                u16 parm_version;
+                u64 token_addr;
+                u64 select_mask;
+                u64 compare_mask;
+                u64 zarch;
+        };
+        struct prs_parm parm;
+        int rc;
+        u16 rx = (vcpu->arch.sie_block->ipa & 0xf0) >> 4;
+        u16 ry = (vcpu->arch.sie_block->ipa & 0x0f);
+        unsigned long hva_token = KVM_HVA_ERR_BAD;
+
+        if (vcpu->run->s.regs.gprs[rx] & 7)
+                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
+        if (copy_from_guest(vcpu, &parm, vcpu->run->s.regs.gprs[rx], sizeof(parm)))
+                return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
+        if (parm.parm_version != 2 || parm.parm_len < 5 || parm.code != 0x258)
+                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
+
+        switch (parm.subcode) {
+        case 0: /* TOKEN */
+                if (vcpu->arch.pfault_token != KVM_S390_PFAULT_TOKEN_INVALID) {
+                        /*
+                         * If the pagefault handshake is already activated,
+                         * the token must not be changed.  We have to return
+                         * decimal 8 instead, as mandated in SC24-6084.
+                         */
+                        vcpu->run->s.regs.gprs[ry] = 8;
+                        return 0;
+                }
+
+                if ((parm.compare_mask & parm.select_mask) != parm.compare_mask ||
+                    parm.token_addr & 7 || parm.zarch != 0x8000000000000000ULL)
+                        return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
+
+                hva_token = gfn_to_hva(vcpu->kvm, gpa_to_gfn(parm.token_addr));
+                if (kvm_is_error_hva(hva_token))
+                        return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
+
+                vcpu->arch.pfault_token = parm.token_addr;
+                vcpu->arch.pfault_select = parm.select_mask;
+                vcpu->arch.pfault_compare = parm.compare_mask;
+                vcpu->run->s.regs.gprs[ry] = 0;
+                rc = 0;
+                break;
+        case 1: /*
+                 * CANCEL
+                 * Specification allows to let already pending tokens survive
+                 * the cancel, therefore to reduce code complexity, we assume
+                 * all outstanding tokens are already pending.
+                 */
+                if (parm.token_addr || parm.select_mask ||
+                    parm.compare_mask || parm.zarch)
+                        return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
+
+                vcpu->run->s.regs.gprs[ry] = 0;
+                /*
+                 * If the pfault handling was not established or is already
+                 * canceled SC24-6084 requests to return decimal 4.
+                 */
+                if (vcpu->arch.pfault_token == KVM_S390_PFAULT_TOKEN_INVALID)
+                        vcpu->run->s.regs.gprs[ry] = 4;
+                else
+                        vcpu->arch.pfault_token = KVM_S390_PFAULT_TOKEN_INVALID;
+
+                rc = 0;
+                break;
+        default:
+                rc = -EOPNOTSUPP;
+                break;
+        }
+
+        return rc;
+}
+
 static int __diag_time_slice_end(struct kvm_vcpu *vcpu)
 {
         VCPU_EVENT(vcpu, 5, "%s", "diag time slice end");
@@ -85,6 +167,10 @@ static int __diag_ipl_functions(struct kvm_vcpu *vcpu)
 
         VCPU_EVENT(vcpu, 5, "diag ipl functions, subcode %lx", subcode);
         switch (subcode) {
+        case 0:
+        case 1:
+                page_table_reset_pgste(current->mm, 0, TASK_SIZE);
+                return -EOPNOTSUPP;
         case 3:
                 vcpu->run->s390_reset_flags = KVM_S390_RESET_CLEAR;
                 page_table_reset_pgste(current->mm, 0, TASK_SIZE);
@@ -153,6 +239,8 @@ int kvm_s390_handle_diag(struct kvm_vcpu *vcpu)
                 return __diag_time_slice_end(vcpu);
         case 0x9c:
                 return __diag_time_slice_end_directed(vcpu);
+        case 0x258:
+                return __diag_page_ref_service(vcpu);
         case 0x308:
                 return __diag_ipl_functions(vcpu);
         case 0x500: