diff options
| -rw-r--r-- | accel/tcg/cputlb.c | 12 | ||||
| -rw-r--r-- | include/exec/cpu-defs.h | 9 |
2 files changed, 21 insertions, 0 deletions
diff --git a/accel/tcg/cputlb.c b/accel/tcg/cputlb.c index 05439039e9..31f7695cb2 100644 --- a/accel/tcg/cputlb.c +++ b/accel/tcg/cputlb.c @@ -664,6 +664,18 @@ void tlb_set_page_with_attrs(CPUState *cpu, target_ulong vaddr, env->iotlb_v[mmu_idx][vidx] = env->iotlb[mmu_idx][index]; /* refill the tlb */ + /* + * At this point iotlb contains a physical section number in the lower + * TARGET_PAGE_BITS, and either + * + the ram_addr_t of the page base of the target RAM (if NOTDIRTY or ROM) + * + the offset within section->mr of the page base (otherwise) + * We subtract the vaddr (which is page aligned and thus won't + * disturb the low bits) to give an offset which can be added to the + * (non-page-aligned) vaddr of the eventual memory access to get + * the MemoryRegion offset for the access. Note that the vaddr we + * subtract here is that of the page base, and not the same as the + * vaddr we add back in io_readx()/io_writex()/get_page_addr_code(). + */ env->iotlb[mmu_idx][index].addr = iotlb - vaddr; env->iotlb[mmu_idx][index].attrs = attrs; diff --git a/include/exec/cpu-defs.h b/include/exec/cpu-defs.h index e43ff8346b..a171ffc1a4 100644 --- a/include/exec/cpu-defs.h +++ b/include/exec/cpu-defs.h @@ -127,6 +127,15 @@ QEMU_BUILD_BUG_ON(sizeof(CPUTLBEntry) != (1 << CPU_TLB_ENTRY_BITS)); * structs into one.) */ typedef struct CPUIOTLBEntry { + /* + * @addr contains: + * - in the lower TARGET_PAGE_BITS, a physical section number + * - with the lower TARGET_PAGE_BITS masked off, an offset which + * must be added to the virtual address to obtain: + * + the ram_addr_t of the target RAM (if the physical section + * number is PHYS_SECTION_NOTDIRTY or PHYS_SECTION_ROM) + * + the offset within the target MemoryRegion (otherwise) + */ hwaddr addr; MemTxAttrs attrs; } CPUIOTLBEntry; |