Let's add indirect data addressing support for our virtual channel subsystem. This implementation does no bother with any kind of prefetching. We simply step trough the IDAL on demand.
Signed-off-by: Halil Pasic <pa...@linux.vnet.ibm.com> --- hw/s390x/css.c | 109 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 108 insertions(+), 1 deletion(-) diff --git a/hw/s390x/css.c b/hw/s390x/css.c index 6b0cd8861b..e34b2af4eb 100644 --- a/hw/s390x/css.c +++ b/hw/s390x/css.c @@ -819,6 +819,113 @@ incr: return 0; } +/* returns values between 1 and bsz, where bs 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) +{ + return 1ULL << (((flags ^ CDS_F_C64) & (CDS_F_C64 | CDS_F_I2K)) ? 11 : 12); +} + +static inline int ida_read_next_idaw(CcwDataStream *cds) +{ + union {uint64_t fmt2; uint32_t fmt1; } idaw; + bool is_fmt2 = cds->flags & CDS_F_C64; + int ret; + hwaddr idaw_addr; + + if (is_fmt2) { + idaw_addr = cds->cda_orig + sizeof(idaw.fmt2) * cds->at_idaw; + if (idaw_addr & 0x07) { + return -EINVAL; /* channel program check */ + } + ret = address_space_rw(&address_space_memory, 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) { + 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); + } + ++(cds->at_idaw); + if (ret != MEMTX_OK) { + /* assume inaccessible address */ + return -EINVAL; /* channel program check */ + + } + 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; + + ret = cds_check_len(cds, len); + if (ret <= 0) { + return ret; + } + if (!cds->at_idaw) { + /* read first idaw */ + ret = ida_read_next_idaw(cds); + if (ret) { + goto err; + } + cont_left = ida_continuous_left(cds->cda, bsz); + } else { + cont_left = ida_continuous_left(cds->cda, bsz); + if (cont_left == bsz) { + ret = ida_read_next_idaw(cds); + if (ret) { + goto err; + } + if (cds->cda & (bsz - 1)) { + ret = -EINVAL; /* channel program check */ + goto err; + } + } + } + do { + iter_len = MIN(len, cont_left); + if (op != CDS_OP_A) { + ret = address_space_rw(&address_space_memory, cds->cda, + MEMTXATTRS_UNSPECIFIED, buff, iter_len, op); + if (ret != MEMTX_OK) { + /* assume inaccessible address */ + ret = -EINVAL; /* channel program check */ + goto err; + } + } + cds->at_byte += iter_len; + cds->cda += iter_len; + len -= iter_len; + if (!len) { + break; + } + ret = ida_read_next_idaw(cds); + if (ret) { + goto err; + } + cont_left = bsz; + } while (true); + return ret; +err: + cds->flags |= CDS_F_STREAM_BROKEN; + return ret; +} + void ccw_dstream_init(CcwDataStream *cds, CCW1 const *ccw, ORB const *orb) { /* @@ -835,7 +942,7 @@ void ccw_dstream_init(CcwDataStream *cds, CCW1 const *ccw, ORB const *orb) if (!(cds->flags & CDS_F_IDA)) { cds->op_handler = ccw_dstream_rw_noflags; } else { - assert(false); + cds->op_handler = ccw_dstream_rw_ida; } } -- 2.13.5