arch_rebalance_pgtables call
In order to change the layout of the page tables after an mmap has crossed the
adress space limit of the current page table layout a architecture hook in
get_unmapped_area is needed. The arguments are the address of the new mapping
and the length of it.
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/mmap.c b/mm/mmap.c
index 8295577..bb4c963 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -36,6 +36,10 @@
#define arch_mmap_check(addr, len, flags) (0)
#endif
+#ifndef arch_rebalance_pgtables
+#define arch_rebalance_pgtables(addr, len) (addr)
+#endif
+
static void unmap_region(struct mm_struct *mm,
struct vm_area_struct *vma, struct vm_area_struct *prev,
unsigned long start, unsigned long end);
@@ -1424,7 +1428,7 @@
if (addr & ~PAGE_MASK)
return -EINVAL;
- return addr;
+ return arch_rebalance_pgtables(addr, len);
}
EXPORT_SYMBOL(get_unmapped_area);