diff options
| -rw-r--r-- | arch/s390/include/asm/pgtable.h | 3 | ||||
| -rw-r--r-- | arch/s390/kvm/priv.c | 18 | ||||
| -rw-r--r-- | arch/s390/mm/pgtable.c | 33 |
3 files changed, 50 insertions, 4 deletions
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index 91f0e7b79821..2f6702e27db9 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -893,6 +893,9 @@ void ptep_zap_key(struct mm_struct *mm, unsigned long addr, pte_t *ptep); bool test_and_clear_guest_dirty(struct mm_struct *mm, unsigned long address); int set_guest_storage_key(struct mm_struct *mm, unsigned long addr, unsigned char key, bool nq); +int cond_set_guest_storage_key(struct mm_struct *mm, unsigned long addr, + unsigned char key, unsigned char *oldkey, + bool nq, bool mr, bool mc); int get_guest_storage_key(struct mm_struct *mm, unsigned long addr, unsigned char *key); diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c index 71fa603034d0..752a1ac1aab6 100644 --- a/arch/s390/kvm/priv.c +++ b/arch/s390/kvm/priv.c @@ -654,8 +654,10 @@ static int handle_epsw(struct kvm_vcpu *vcpu) static int handle_pfmf(struct kvm_vcpu *vcpu) { + bool mr = false, mc = false, nq; int reg1, reg2; unsigned long start, end; + unsigned char key; vcpu->stat.instruction_pfmf++; @@ -675,6 +677,15 @@ static int handle_pfmf(struct kvm_vcpu *vcpu) !test_kvm_facility(vcpu->kvm, 14)) return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION); + /* Only provide conditional-SSKE support if enabled for the guest */ + if (vcpu->run->s.regs.gprs[reg1] & PFMF_SK && + test_kvm_facility(vcpu->kvm, 10)) { + mr = vcpu->run->s.regs.gprs[reg1] & PFMF_MR; + mc = vcpu->run->s.regs.gprs[reg1] & PFMF_MC; + } + + nq = vcpu->run->s.regs.gprs[reg1] & PFMF_NQ; + key = vcpu->run->s.regs.gprs[reg1] & PFMF_KEY; start = vcpu->run->s.regs.gprs[reg2] & PAGE_MASK; start = kvm_s390_logical_to_effective(vcpu, start); @@ -723,11 +734,10 @@ static int handle_pfmf(struct kvm_vcpu *vcpu) if (rc) return rc; down_read(¤t->mm->mmap_sem); - rc = set_guest_storage_key(current->mm, useraddr, - vcpu->run->s.regs.gprs[reg1] & PFMF_KEY, - vcpu->run->s.regs.gprs[reg1] & PFMF_NQ); + rc = cond_set_guest_storage_key(current->mm, useraddr, + key, NULL, nq, mr, mc); up_read(¤t->mm->mmap_sem); - if (rc) + if (rc < 0) return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING); } diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c index 3e35298758d6..e791e8b27fd2 100644 --- a/arch/s390/mm/pgtable.c +++ b/arch/s390/mm/pgtable.c @@ -539,6 +539,39 @@ int set_guest_storage_key(struct mm_struct *mm, unsigned long addr, } EXPORT_SYMBOL(set_guest_storage_key); +/** + * Conditionally set a guest storage key (handling csske). + * oldkey will be updated when either mr or mc is set and a pointer is given. + * + * Returns 0 if a guests storage key update wasn't necessary, 1 if the guest + * storage key was updated and -EFAULT on access errors. + */ +int cond_set_guest_storage_key(struct mm_struct *mm, unsigned long addr, + unsigned char key, unsigned char *oldkey, + bool nq, bool mr, bool mc) +{ + unsigned char tmp, mask = _PAGE_ACC_BITS | _PAGE_FP_BIT; + int rc; + + /* we can drop the pgste lock between getting and setting the key */ + if (mr | mc) { + rc = get_guest_storage_key(current->mm, addr, &tmp); + if (rc) + return rc; + if (oldkey) + *oldkey = tmp; + if (!mr) + mask |= _PAGE_REFERENCED; + if (!mc) + mask |= _PAGE_CHANGED; + if (!((tmp ^ key) & mask)) + return 0; + } + rc = set_guest_storage_key(current->mm, addr, key, nq); + return rc < 0 ? rc : 1; +} +EXPORT_SYMBOL(cond_set_guest_storage_key); + int get_guest_storage_key(struct mm_struct *mm, unsigned long addr, unsigned char *key) { |