The following patch will expose __update_cache to highmem pages. Handle
them by mapping them in for the duration of the cache maintenance, just
like in __flush_dcache_page. The code for that isn't shared because we
need the page address in __update_cache so sharing became messy. Given
that the entirity is an extra 5 lines, just duplicate it.
Signed-off-by: Paul Burton <paul.burton@xxxxxxxxxx>
Cc: Lars Persson <lars.persson@xxxxxxxx>
Cc: stable <stable@xxxxxxxxxxxxxxx> # v4.1+
---
arch/mips/mm/cache.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/arch/mips/mm/cache.c b/arch/mips/mm/cache.c
index 5a67d8c..8befa55 100644
--- a/arch/mips/mm/cache.c
+++ b/arch/mips/mm/cache.c
@@ -149,9 +149,17 @@ void __update_cache(struct vm_area_struct *vma, unsigned long address,
return;
page = pfn_to_page(pfn);
if (page_mapping(page) && Page_dcache_dirty(page)) {
- addr = (unsigned long) page_address(page);
+ if (PageHighMem(page))
+ addr = (unsigned long)kmap_atomic(page);
+ else
+ addr = (unsigned long)page_address(page);
+
if (exec || pages_do_alias(addr, address & PAGE_MASK))
flush_data_cache_page(addr);
+
+ if (PageHighMem(page))
+ __kunmap_atomic((void *)addr);
+
ClearPageDcacheDirty(page);
}
}
--
2.7.1
