Il 04/02/2014 08:55, Alexander Graf ha scritto:
>> With this change, the
>> memory system is now refusing to allow an access of size
>> 2 through, because it's greater than the region length. So
>
> Ouch. Yes, for ioport reads/writes we definitely have to only cap the port
> range, not the length.
We can do it in general for MMIO. Something like this?
diff --git a/exec.c b/exec.c
index 9ad0a4b..9a1eef3 100644
--- a/exec.c
+++ b/exec.c
@@ -325,7 +325,7 @@ address_space_translate_internal(AddressSpaceDispatch *d,
hwaddr addr, hwaddr *x
hwaddr *plen, bool resolve_subpage)
{
MemoryRegionSection *section;
- Int128 diff, diff_page;
+ Int128 diff;
section = address_space_lookup_region(d, addr, resolve_subpage);
/* Compute offset within MemoryRegionSection */
@@ -334,9 +334,7 @@ address_space_translate_internal(AddressSpaceDispatch *d,
hwaddr addr, hwaddr *x
/* Compute offset within MemoryRegion */
*xlat = addr + section->offset_within_region;
- diff_page = int128_make64(((addr & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE) -
addr);
diff = int128_sub(section->mr->size, int128_make64(addr));
- diff = int128_min(diff, diff_page);
*plen = int128_get64(int128_min(diff, int128_make64(*plen)));
return section;
}
@@ -370,6 +368,11 @@ MemoryRegion *address_space_translate(AddressSpace *as,
hwaddr addr,
as = iotlb.target_as;
}
+ if (memory_access_is_direct(mr, is_write)) {
+ hwaddr page = (addr & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE - addr;
+ len = MIN(page, len);
+ }
+
*plen = len;
*xlat = addr;
return mr;
Stefano, Anthony, can you test it on Xen?
I wouldn't mind sticking a "xen_enabled()" in there, and/or a comment to
document
why we do it.
Paolo
