memory: add address_space_translate
Using phys_page_find to translate an AddressSpace to a MemoryRegionSection
is unwieldy. It requires to pass the page index rather than the address,
and later memory_region_section_addr has to be called. Replace
memory_region_section_addr with a function that does all of it: call
phys_page_find, compute the offset within the region, and check how
big the current mapping is. This way, a large flat region can be written
with a single lookup rather than a page at a time.
address_space_translate will also provide a single point where IOMMU
forwarding is implemented.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/include/exec/memory.h b/include/exec/memory.h
index fdf55fe..688d3f0 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -752,23 +752,6 @@
hwaddr addr, uint64_t size);
/**
- * memory_region_section_addr: get offset within MemoryRegionSection
- *
- * Returns offset within MemoryRegionSection
- *
- * @section: the memory region section being queried
- * @addr: address in address space
- */
-static inline hwaddr
-memory_region_section_addr(MemoryRegionSection *section,
- hwaddr addr)
-{
- addr -= section->offset_within_address_space;
- addr += section->offset_within_region;
- return addr;
-}
-
-/**
* address_space_sync_dirty_bitmap: synchronize the dirty log for all memory
*
* Synchronizes the dirty page log for an entire address space.
@@ -869,6 +852,20 @@
*/
void address_space_read(AddressSpace *as, hwaddr addr, uint8_t *buf, int len);
+/* address_space_translate: translate an address range into an address space
+ * into a MemoryRegionSection and an address range into that section
+ *
+ * @as: #AddressSpace to be accessed
+ * @addr: address within that address space
+ * @xlat: pointer to address within the returned memory region section's
+ * #MemoryRegion.
+ * @len: pointer to length
+ * @is_write: indicates the transfer direction
+ */
+MemoryRegionSection *address_space_translate(AddressSpace *as, hwaddr addr,
+ hwaddr *xlat, hwaddr *len,
+ bool is_write);
+
/* address_space_map: map a physical memory region into a host virtual address
*
* May map a subset of the requested range, given by and returned in @plen.
