diff options
| -rw-r--r-- | arch/s390/kvm/vsie.c | 31 |
1 files changed, 29 insertions, 2 deletions
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c index 747d4f900155..2839efcfc5ff 100644 --- a/arch/s390/kvm/vsie.c +++ b/arch/s390/kvm/vsie.c @@ -62,6 +62,11 @@ static void prefix_mapped(struct vsie_page *vsie_page) atomic_andnot(PROG_REQUEST, &vsie_page->scb_s.prog20); } +/* test if the prefix is mapped into the gmap shadow */ +static int prefix_is_mapped(struct vsie_page *vsie_page) +{ + return !(atomic_read(&vsie_page->scb_s.prog20) & PROG_REQUEST); +} /* copy the updated intervention request bits into the shadow scb */ static void update_intervention_requests(struct vsie_page *vsie_page) @@ -152,6 +157,7 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) { struct kvm_s390_sie_block *scb_o = vsie_page->scb_o; struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; + unsigned long new_mso; int rc; /* make sure we don't have any leftovers when reusing the scb */ @@ -192,9 +198,13 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) scb_s->ictl |= ICTL_ISKE | ICTL_SSKE | ICTL_RRBE; scb_s->icpua = scb_o->icpua; + new_mso = scb_o->mso & 0xfffffffffff00000UL; + /* if the hva of the prefix changes, we have to remap the prefix */ + if (scb_s->mso != new_mso || scb_s->prefix != scb_o->prefix) + prefix_unmapped(vsie_page); /* SIE will do mso/msl validity and exception checks for us */ scb_s->msl = scb_o->msl & 0xfffffffffff00000UL; - scb_s->mso = scb_o->mso & 0xfffffffffff00000UL; + scb_s->mso = new_mso; scb_s->prefix = scb_o->prefix; /* We have to definetly flush the tlb if this scb never ran */ @@ -262,6 +272,9 @@ static int map_prefix(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) u64 prefix = scb_s->prefix << GUEST_PREFIX_SHIFT; int rc; + if (prefix_is_mapped(vsie_page)) + return 0; + /* mark it as mapped so we can catch any concurrent unmappers */ prefix_mapped(vsie_page); @@ -532,6 +545,7 @@ static void release_gmap_shadow(struct vsie_page *vsie_page) if (vsie_page->gmap) gmap_put(vsie_page->gmap); WRITE_ONCE(vsie_page->gmap, NULL); + prefix_unmapped(vsie_page); } static int acquire_gmap_shadow(struct kvm_vcpu *vcpu, @@ -547,6 +561,16 @@ static int acquire_gmap_shadow(struct kvm_vcpu *vcpu, edat = cr0.edat && test_kvm_facility(vcpu->kvm, 8); edat += edat && test_kvm_facility(vcpu->kvm, 78); + /* + * ASCE or EDAT could have changed since last icpt, or the gmap + * we're holding has been unshadowed. If the gmap is still valid, + * we can safely reuse it. + */ + if (vsie_page->gmap && gmap_shadow_valid(vsie_page->gmap, asce, edat)) + return 0; + + /* release the old shadow - if any, and mark the prefix as unmapped */ + release_gmap_shadow(vsie_page); gmap = gmap_shadow(vcpu->arch.gmap, asce, edat); if (IS_ERR(gmap)) return PTR_ERR(gmap); @@ -578,7 +602,6 @@ static int vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) rc = do_vsie_run(vcpu, vsie_page); gmap_enable(vcpu->arch.gmap); } - release_gmap_shadow(vsie_page); if (rc == -EAGAIN) rc = 0; @@ -667,6 +690,7 @@ static struct vsie_page *get_vsie_page(struct kvm *kvm, unsigned long addr) vsie_page = page_to_virt(page); memset(&vsie_page->scb_s, 0, sizeof(struct kvm_s390_sie_block)); + release_gmap_shadow(vsie_page); vsie_page->scb_s.ihcpu = 0xffffU; return vsie_page; } @@ -739,6 +763,7 @@ void kvm_s390_vsie_init(struct kvm *kvm) /* Destroy the vsie data structures. To be called when a vm is destroyed. */ void kvm_s390_vsie_destroy(struct kvm *kvm) { + struct vsie_page *vsie_page; struct page *page; int i; @@ -746,6 +771,8 @@ void kvm_s390_vsie_destroy(struct kvm *kvm) for (i = 0; i < kvm->arch.vsie.page_count; i++) { page = kvm->arch.vsie.pages[i]; kvm->arch.vsie.pages[i] = NULL; + vsie_page = page_to_virt(page); + release_gmap_shadow(vsie_page); /* free the radix tree entry */ radix_tree_delete(&kvm->arch.vsie.addr_to_page, page->index >> 9); __free_page(page); |