KVM: s390: Improved MVPG partial execution handler

Use the new helper function kvm_arch_fault_in_page() for faulting-in
the guest pages and only inject addressing errors when we've really
hit a bad address (and return other error codes to userspace instead).

Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

1 files changed, 9 insertions, 16 deletions

diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c
index ddc69f5f5e19..147b87fefecd 100644
--- a/arch/s390/kvm/intercept.c
+++ b/arch/s390/kvm/intercept.c
@@ -292,33 +292,26 @@ static int handle_external_interrupt(struct kvm_vcpu *vcpu)
  */
 static int handle_mvpg_pei(struct kvm_vcpu *vcpu)
 {
-        unsigned long hostaddr, srcaddr, dstaddr;
         psw_t *psw = &vcpu->arch.sie_block->gpsw;
-        struct mm_struct *mm = current->mm;
+        unsigned long srcaddr, dstaddr;
         int reg1, reg2, rc;
 
         kvm_s390_get_regs_rre(vcpu, &reg1, &reg2);
-        srcaddr = kvm_s390_real_to_abs(vcpu, vcpu->run->s.regs.gprs[reg2]);
-        dstaddr = kvm_s390_real_to_abs(vcpu, vcpu->run->s.regs.gprs[reg1]);
 
         /* Make sure that the source is paged-in */
-        hostaddr = gmap_fault(srcaddr, vcpu->arch.gmap);
-        if (IS_ERR_VALUE(hostaddr))
+        srcaddr = kvm_s390_real_to_abs(vcpu, vcpu->run->s.regs.gprs[reg2]);
+        if (kvm_is_error_gpa(vcpu->kvm, srcaddr))
                 return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
-        down_read(&mm->mmap_sem);
-        rc = get_user_pages(current, mm, hostaddr, 1, 0, 0, NULL, NULL);
-        up_read(&mm->mmap_sem);
-        if (rc < 0)
+        rc = kvm_arch_fault_in_page(vcpu, srcaddr, 0);
+        if (rc != 0)
                 return rc;
 
         /* Make sure that the destination is paged-in */
-        hostaddr = gmap_fault(dstaddr, vcpu->arch.gmap);
-        if (IS_ERR_VALUE(hostaddr))
+        dstaddr = kvm_s390_real_to_abs(vcpu, vcpu->run->s.regs.gprs[reg1]);
+        if (kvm_is_error_gpa(vcpu->kvm, dstaddr))
                 return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
-        down_read(&mm->mmap_sem);
-        rc = get_user_pages(current, mm, hostaddr, 1, 1, 0, NULL, NULL);
-        up_read(&mm->mmap_sem);
-        if (rc < 0)
+        rc = kvm_arch_fault_in_page(vcpu, dstaddr, 1);
+        if (rc != 0)
                 return rc;
 
         psw->addr = __rewind_psw(*psw, 4);