Refactor some storage key functions to improve readability. Introduce helper functions that will be used in the next patches. Signed-off-by: Claudio Imbrenda --- arch/s390/kvm/gaccess.c | 36 +++++++++--------- arch/s390/kvm/gaccess.h | 4 +- arch/s390/kvm/kvm-s390.c | 80 +++++++++++++++------------------------- arch/s390/kvm/kvm-s390.h | 8 ++++ 4 files changed, 58 insertions(+), 70 deletions(-) diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c index 05fd3ee4b20d..a054de80a5cc 100644 --- a/arch/s390/kvm/gaccess.c +++ b/arch/s390/kvm/gaccess.c @@ -989,9 +989,8 @@ int access_guest_real(struct kvm_vcpu *vcpu, unsigned long gra, * * -EAGAIN: transient failure (len 1 or 2) * * -EOPNOTSUPP: read-only memslot (should never occur) */ -int cmpxchg_guest_abs_with_key(struct kvm *kvm, gpa_t gpa, int len, - __uint128_t *old_addr, __uint128_t new, - u8 access_key, bool *success) +int cmpxchg_guest_abs_with_key(struct kvm *kvm, gpa_t gpa, int len, union kvm_s390_quad *old_addr, + union kvm_s390_quad new, u8 acc, bool *success) { gfn_t gfn = gpa_to_gfn(gpa); struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn); @@ -1023,41 +1022,42 @@ int cmpxchg_guest_abs_with_key(struct kvm *kvm, gpa_t gpa, int len, case 1: { u8 old; - ret = cmpxchg_user_key((u8 __user *)hva, &old, *old_addr, new, access_key); - *success = !ret && old == *old_addr; - *old_addr = old; + ret = cmpxchg_user_key((u8 __user *)hva, &old, old_addr->one, new.one, acc); + *success = !ret && old == old_addr->one; + old_addr->one = old; break; } case 2: { u16 old; - ret = cmpxchg_user_key((u16 __user *)hva, &old, *old_addr, new, access_key); - *success = !ret && old == *old_addr; - *old_addr = old; + ret = cmpxchg_user_key((u16 __user *)hva, &old, old_addr->two, new.two, acc); + *success = !ret && old == old_addr->two; + old_addr->two = old; break; } case 4: { u32 old; - ret = cmpxchg_user_key((u32 __user *)hva, &old, *old_addr, new, access_key); - *success = !ret && old == *old_addr; - *old_addr = old; + ret = cmpxchg_user_key((u32 __user *)hva, &old, old_addr->four, new.four, acc); + *success = !ret && old == old_addr->four; + old_addr->four = old; break; } case 8: { u64 old; - ret = cmpxchg_user_key((u64 __user *)hva, &old, *old_addr, new, access_key); - *success = !ret && old == *old_addr; - *old_addr = old; + ret = cmpxchg_user_key((u64 __user *)hva, &old, old_addr->eight, new.eight, acc); + *success = !ret && old == old_addr->eight; + old_addr->eight = old; break; } case 16: { __uint128_t old; - ret = cmpxchg_user_key((__uint128_t __user *)hva, &old, *old_addr, new, access_key); - *success = !ret && old == *old_addr; - *old_addr = old; + ret = cmpxchg_user_key((__uint128_t __user *)hva, &old, old_addr->sixteen, + new.sixteen, acc); + *success = !ret && old == old_addr->sixteen; + old_addr->sixteen = old; break; } default: diff --git a/arch/s390/kvm/gaccess.h b/arch/s390/kvm/gaccess.h index 3fde45a151f2..774cdf19998f 100644 --- a/arch/s390/kvm/gaccess.h +++ b/arch/s390/kvm/gaccess.h @@ -206,8 +206,8 @@ int access_guest_with_key(struct kvm_vcpu *vcpu, unsigned long ga, u8 ar, int access_guest_real(struct kvm_vcpu *vcpu, unsigned long gra, void *data, unsigned long len, enum gacc_mode mode); -int cmpxchg_guest_abs_with_key(struct kvm *kvm, gpa_t gpa, int len, __uint128_t *old, - __uint128_t new, u8 access_key, bool *success); +int cmpxchg_guest_abs_with_key(struct kvm *kvm, gpa_t gpa, int len, union kvm_s390_quad *old_addr, + union kvm_s390_quad new, u8 access_key, bool *success); /** * write_guest_with_key - copy data from kernel space to guest space diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index d7eff75a53d0..ab69c9fd7926 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -2905,9 +2905,9 @@ static int mem_op_validate_common(struct kvm_s390_mem_op *mop, u64 supported_fla static int kvm_s390_vm_mem_op_abs(struct kvm *kvm, struct kvm_s390_mem_op *mop) { void __user *uaddr = (void __user *)mop->buf; + void *tmpbuf __free(kvfree) = NULL; enum gacc_mode acc_mode; - void *tmpbuf = NULL; - int r, srcu_idx; + int r; r = mem_op_validate_common(mop, KVM_S390_MEMOP_F_SKEY_PROTECTION | KVM_S390_MEMOP_F_CHECK_ONLY); @@ -2920,52 +2920,36 @@ static int kvm_s390_vm_mem_op_abs(struct kvm *kvm, struct kvm_s390_mem_op *mop) return -ENOMEM; } - srcu_idx = srcu_read_lock(&kvm->srcu); + acc_mode = mop->op == KVM_S390_MEMOP_ABSOLUTE_READ ? GACC_FETCH : GACC_STORE; - if (!kvm_is_gpa_in_memslot(kvm, mop->gaddr)) { - r = PGM_ADDRESSING; - goto out_unlock; - } + scoped_guard(srcu, &kvm->srcu) { + if (!kvm_is_gpa_in_memslot(kvm, mop->gaddr)) + return PGM_ADDRESSING; - acc_mode = mop->op == KVM_S390_MEMOP_ABSOLUTE_READ ? GACC_FETCH : GACC_STORE; - if (mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY) { - r = check_gpa_range(kvm, mop->gaddr, mop->size, acc_mode, mop->key); - goto out_unlock; - } - if (acc_mode == GACC_FETCH) { + if (mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY) + return check_gpa_range(kvm, mop->gaddr, mop->size, acc_mode, mop->key); + + if (acc_mode == GACC_STORE && copy_from_user(tmpbuf, uaddr, mop->size)) + return -EFAULT; r = access_guest_abs_with_key(kvm, mop->gaddr, tmpbuf, - mop->size, GACC_FETCH, mop->key); + mop->size, acc_mode, mop->key); if (r) - goto out_unlock; - if (copy_to_user(uaddr, tmpbuf, mop->size)) - r = -EFAULT; - } else { - if (copy_from_user(tmpbuf, uaddr, mop->size)) { - r = -EFAULT; - goto out_unlock; - } - r = access_guest_abs_with_key(kvm, mop->gaddr, tmpbuf, - mop->size, GACC_STORE, mop->key); + return r; + if (acc_mode != GACC_STORE && copy_to_user(uaddr, tmpbuf, mop->size)) + return -EFAULT; } -out_unlock: - srcu_read_unlock(&kvm->srcu, srcu_idx); - - vfree(tmpbuf); - return r; + return 0; } static int kvm_s390_vm_mem_op_cmpxchg(struct kvm *kvm, struct kvm_s390_mem_op *mop) { void __user *uaddr = (void __user *)mop->buf; void __user *old_addr = (void __user *)mop->old_addr; - union { - __uint128_t quad; - char raw[sizeof(__uint128_t)]; - } old = { .quad = 0}, new = { .quad = 0 }; - unsigned int off_in_quad = sizeof(new) - mop->size; - int r, srcu_idx; - bool success; + union kvm_s390_quad old = { .sixteen = 0 }; + union kvm_s390_quad new = { .sixteen = 0 }; + bool success = false; + int r; r = mem_op_validate_common(mop, KVM_S390_MEMOP_F_SKEY_PROTECTION); if (r) @@ -2977,25 +2961,21 @@ static int kvm_s390_vm_mem_op_cmpxchg(struct kvm *kvm, struct kvm_s390_mem_op *m */ if (mop->size > sizeof(new)) return -EINVAL; - if (copy_from_user(&new.raw[off_in_quad], uaddr, mop->size)) + if (copy_from_user(&new, uaddr, mop->size)) return -EFAULT; - if (copy_from_user(&old.raw[off_in_quad], old_addr, mop->size)) + if (copy_from_user(&old, old_addr, mop->size)) return -EFAULT; - srcu_idx = srcu_read_lock(&kvm->srcu); + scoped_guard(srcu, &kvm->srcu) { + if (!kvm_is_gpa_in_memslot(kvm, mop->gaddr)) + return PGM_ADDRESSING; - if (!kvm_is_gpa_in_memslot(kvm, mop->gaddr)) { - r = PGM_ADDRESSING; - goto out_unlock; - } - - r = cmpxchg_guest_abs_with_key(kvm, mop->gaddr, mop->size, &old.quad, - new.quad, mop->key, &success); - if (!success && copy_to_user(old_addr, &old.raw[off_in_quad], mop->size)) - r = -EFAULT; + r = cmpxchg_guest_abs_with_key(kvm, mop->gaddr, mop->size, &old, new, + mop->key, &success); -out_unlock: - srcu_read_unlock(&kvm->srcu, srcu_idx); + if (!success && copy_to_user(old_addr, &old, mop->size)) + return -EFAULT; + } return r; } diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h index f89f9f698df5..495ee9caaa30 100644 --- a/arch/s390/kvm/kvm-s390.h +++ b/arch/s390/kvm/kvm-s390.h @@ -22,6 +22,14 @@ #define KVM_S390_UCONTROL_MEMSLOT (KVM_USER_MEM_SLOTS + 0) +union kvm_s390_quad { + __uint128_t sixteen; + unsigned long eight; + unsigned int four; + unsigned short two; + unsigned char one; +}; + static inline void kvm_s390_fpu_store(struct kvm_run *run) { fpu_stfpc(&run->s.regs.fpc); -- 2.51.1