Commit 65a27df9 authored by David Hildenbrand's avatar David Hildenbrand
Browse files

s390x/tcg: MVCIN: Fault-safe handling 



We can process a maximum of 256 bytes, crossing two pages. Calculate the
accessed range upfront - src is accessed right-to-left.

Reviewed-by: default avatarRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
parent 4d78c68b

target/s390x/mem_helper.c

+12 −3
Original line number Diff line number Diff line
@@ -479,12 +479,21 @@ void HELPER(mvc)(CPUS390XState *env, uint32_t l, uint64_t dest, uint64_t src) 
/* move inverse  */

void HELPER(mvcin)(CPUS390XState *env, uint32_t l, uint64_t dest, uint64_t src)

{

    const int mmu_idx = cpu_mmu_index(env, false);

    S390Access srca, desta;

    uintptr_t ra = GETPC();

    int i;



    for (i = 0; i <= l; i++) {

        uint8_t v = cpu_ldub_data_ra(env, src - i, ra);

        cpu_stb_data_ra(env, dest + i, v, ra);

    /* MVCIN always copies one more byte than specified - maximum is 256 */

    l++;



    src = wrap_address(env, src - l + 1);

    srca = access_prepare(env, src, l, MMU_DATA_LOAD, mmu_idx, ra);

    desta = access_prepare(env, dest, l, MMU_DATA_STORE, mmu_idx, ra);

    for (i = 0; i < l; i++) {

        const uint8_t x = access_get_byte(env, &srca, l - i - 1, ra);



        access_set_byte(env, &desta, i, x, ra);

    }

}