On 18.02.20 12:24, Peter Maydell wrote:
> The address_space_rw() function allows either reads or writes
> depending on the is_write argument passed to it; this is useful
> when the direction of the access is determined programmatically
> (as for instance when handling the KVM_EXIT_MMIO exit reason).
> Under the hood it just calls either address_space_write() or
> address_space_read_full().
>
> We also use it a lot with a constant is_write argument, though,
> which has two issues:
> * when reading "address_space_rw(..., 1)" this is less
> immediately clear to the reader as being a write than
> "address_space_write(...)"
> * calling address_space_rw() bypasses the optimization
> in address_space_read() that fast-paths reads of a
> fixed length
>
> This commit was produced with the included Coccinelle script
> scripts/coccinelle/as-rw-const.patch.
>
> Two lines in hw/net/dp8393x.c that Coccinelle produced that
> were over 80 characters were re-wrapped by hand.
>
> Signed-off-by: Peter Maydell <peter.mayd...@linaro.org>
s390 part
Acked-by: Christian Borntraeger <borntrae...@de.ibm.com>
> ---
> I could break this down into separate patches by submaintainer,
> but the patch is not that large and I would argue that it's
> better for the project if we can try to avoid introducing too
> much friction into the process of doing 'safe' tree-wide
> minor refactorings.
>
> v1->v2: put the coccinelle script in scripts/coccinelle rather
> than just in the commit message.
[...]
> --- a/hw/s390x/css.c
> +++ b/hw/s390x/css.c
> @@ -874,18 +874,18 @@ static inline int ida_read_next_idaw(CcwDataStream *cds)
> if (idaw_addr & 0x07 || !cds_ccw_addrs_ok(idaw_addr, 0, ccw_fmt1)) {
> return -EINVAL; /* channel program check */
> }
> - ret = address_space_rw(&address_space_memory, idaw_addr,
> - MEMTXATTRS_UNSPECIFIED, (void *) &idaw.fmt2,
> - sizeof(idaw.fmt2), false);
> + ret = address_space_read(&address_space_memory, idaw_addr,
> + MEMTXATTRS_UNSPECIFIED, (void *)&idaw.fmt2,
> + sizeof(idaw.fmt2));
> cds->cda = be64_to_cpu(idaw.fmt2);
> } else {
> idaw_addr = cds->cda_orig + sizeof(idaw.fmt1) * cds->at_idaw;
> if (idaw_addr & 0x03 || !cds_ccw_addrs_ok(idaw_addr, 0, ccw_fmt1)) {
> return -EINVAL; /* channel program check */
> }
> - ret = address_space_rw(&address_space_memory, idaw_addr,
> - MEMTXATTRS_UNSPECIFIED, (void *) &idaw.fmt1,
> - sizeof(idaw.fmt1), false);
> + ret = address_space_read(&address_space_memory, idaw_addr,
> + MEMTXATTRS_UNSPECIFIED, (void *)&idaw.fmt1,
> + sizeof(idaw.fmt1));
> cds->cda = be64_to_cpu(idaw.fmt1);
> if (cds->cda & 0x80000000) {
> return -EINVAL; /* channel program check */
