* Halil Pasic <pa...@linux.vnet.ibm.com> [2017-09-19 20:27:45 +0200]:
> Let's add indirect data addressing support for our virtual channel
> subsystem. This implementation does not bother with any kind of
> prefetching. We simply step through the IDAL on demand.
>
> Signed-off-by: Halil Pasic <pa...@linux.vnet.ibm.com>
> Signed-off-by: Cornelia Huck <coh...@redhat.com>
> ---
> hw/s390x/css.c | 117
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 116 insertions(+), 1 deletion(-)
>
> diff --git a/hw/s390x/css.c b/hw/s390x/css.c
> index 2d37a9ddde..a3ce6d89b6 100644
> --- a/hw/s390x/css.c
> +++ b/hw/s390x/css.c
> @@ -827,6 +827,121 @@ incr:
> return 0;
> }
>
> +/* returns values between 1 and bsz, where bsz is a power of 2 */
> +static inline uint16_t ida_continuous_left(hwaddr cda, uint64_t bsz)
> +{
> + return bsz - (cda & (bsz - 1));
> +}
> +
> +static inline uint64_t ccw_ida_block_size(uint8_t flags)
> +{
> + if ((flags & CDS_F_C64) && !(flags & CDS_F_I2K)) {
> + return 1ULL << 12;
> + }
> + return 1ULL << 11;
> +}
> +
> +static inline int ida_read_next_idaw(CcwDataStream *cds, bool ccw_fmt1,
> + bool idaw_fmt_2)
> +{
> + union {uint64_t fmt2; uint32_t fmt1; } idaw;
> + int ret;
> + hwaddr idaw_addr;
> +
> + if (idaw_fmt_2) {
> + idaw_addr = cds->cda_orig + sizeof(idaw.fmt2) * cds->at_idaw;
> + 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,
Ahh, just got one question here:
Do we need to considerate endianess for idaw_addr?
> + MEMTXATTRS_UNSPECIFIED, (void *) &idaw.fmt2,
> + sizeof(idaw.fmt2), false);
> + 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);
> + cds->cda = be64_to_cpu(idaw.fmt1);
Still need to check bit 0x80000000 here I think.
> + }
> + ++(cds->at_idaw);
> + if (ret != MEMTX_OK) {
> + /* assume inaccessible address */
> + return -EINVAL; /* channel program check */
> +
Extra line.
> + }
> + return 0;
> +}
> +
> +static int ccw_dstream_rw_ida(CcwDataStream *cds, void *buff, int len,
> + CcwDataStreamOp op)
> +{
> + uint64_t bsz = ccw_ida_block_size(cds->flags);
> + int ret = 0;
> + uint16_t cont_left, iter_len;
> + const bool idaw_fmt2 = cds->flags & CDS_F_C64;
> + bool ccw_fmt1 = cds->flags & CDS_F_FMT;
Use 'const bool' either? Although I doubt the value of using const here.
;)
> +
> + ret = cds_check_len(cds, len);
> + if (ret <= 0) {
> + return ret;
> + }
[...]
--
Dong Jia Shi
