static int bmdma_rw_buf(IDEDMA *dma, int is_write) { BMDMAState *bm = DO_UPCAST(BMDMAState, dma, dma); IDEState *s = bmdma_active_if(bm); struct { uint32_t addr; uint32_t size; } prd; int l, len; for(;;) { l = s->io_buffer_size - s->io_buffer_index; if (l <= 0) break; if (bm->cur_prd_len == 0) { /* end of table (with a fail safe of one page) */ if (bm->cur_prd_last || (bm->cur_addr - bm->addr) >= BMDMA_PAGE_SIZE) return 0; cpu_physical_memory_read(bm->cur_addr, (uint8_t *)&prd, 8); bm->cur_addr += 8; prd.addr = le32_to_cpu(prd.addr); prd.size = le32_to_cpu(prd.size); len = prd.size & 0xfffe; if (len == 0) len = 0x10000; bm->cur_prd_len = len; bm->cur_prd_addr = prd.addr; bm->cur_prd_last = (prd.size & 0x80000000); } if (l > bm->cur_prd_len) l = bm->cur_prd_len; if (l > 0) { if (is_write) { cpu_physical_memory_write(bm->cur_prd_addr, s->io_buffer + s->io_buffer_index, l); } else { cpu_physical_memory_read(bm->cur_prd_addr, s->io_buffer + s->io_buffer_index, l); } bm->cur_prd_addr += l; bm->cur_prd_len -= l; s->io_buffer_index += l; } } return 1; }