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
