User space can use the MEM_OP ioctl to make storage key checked reads and writes to the guest, however, it has no way of performing atomic, key checked, accesses to the guest. Extend the MEM_OP ioctl in order to allow for this, by adding a cmpxchg mode. For now, support this mode for absolute accesses only. This mode can be use, for example, to set the device-state-change indicator and the adapter-local-summary indicator atomically. Janis Schoetterl-Glausch (9): s390/uaccess: Add storage key checked cmpxchg access to user space KVM: s390: Extend MEM_OP ioctl by storage key checked cmpxchg Documentation: KVM: s390: Describe KVM_S390_MEMOP_F_CMPXCHG KVM: s390: selftest: memop: Pass mop_desc via pointer KVM: s390: selftest: memop: Replace macros by functions KVM: s390: selftest: memop: Add bad address test KVM: s390: selftest: memop: Add cmpxchg tests KVM: s390: selftest: memop: Fix typo KVM: s390: selftest: memop: Fix wrong address being used in test Documentation/virt/kvm/api.rst | 18 +- include/uapi/linux/kvm.h | 5 + arch/s390/include/asm/uaccess.h | 187 ++++++ arch/s390/kvm/gaccess.h | 4 + arch/s390/kvm/gaccess.c | 56 ++ arch/s390/kvm/kvm-s390.c | 50 +- tools/testing/selftests/kvm/s390x/memop.c | 704 +++++++++++++++++----- 7 files changed, 874 insertions(+), 150 deletions(-) base-commit: f76349cf41451c5c42a99f18a9163377e4b364ff -- 2.34.1
