[SPARC64]: Fix D-cache corruption in mremap
If we move a mapping from one virtual address to another,
and this changes the virtual color of the mapping to those
pages, we can see corrupt data due to D-cache aliasing.
Check for and deal with this by overriding the move_pte()
macro. Set things up so that other platforms can cleanly
override the move_pte() macro too.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/asm-sparc64/pgtable.h b/include/asm-sparc64/pgtable.h
index c44e746..cd464f4 100644
--- a/include/asm-sparc64/pgtable.h
+++ b/include/asm-sparc64/pgtable.h
@@ -689,6 +689,23 @@
#define pte_clear(mm,addr,ptep) \
set_pte_at((mm), (addr), (ptep), __pte(0UL))
+#ifdef DCACHE_ALIASING_POSSIBLE
+#define __HAVE_ARCH_MOVE_PTE
+#define move_pte(pte, prot, old_addr, new_addr) \
+({ \
+ pte_t newpte = (pte); \
+ if (tlb_type != hypervisor && pte_present(pte)) { \
+ unsigned long this_pfn = pte_pfn(pte); \
+ \
+ if (pfn_valid(this_pfn) && \
+ (((old_addr) ^ (new_addr)) & (1 << 13))) \
+ flush_dcache_page_all(current->mm, \
+ pfn_to_page(this_pfn)); \
+ } \
+ newpte; \
+})
+#endif
+
extern pgd_t swapper_pg_dir[2048];
extern pmd_t swapper_low_pmd_dir[2048];