nios2: implement flush_dcache_mmap_lock/unlock

Use spin_lock/unlock_irq instead of doing nothing. This fixes corruptions
of the vma_interval_tree causing the kernel to be stuck in an
infinite loop in vma_interval_tree_foreach.

Signed-off-by: Julien Beraud <julien.beraud@spectracom.orolia.com>
Acked-by: Ley Foon Tan <ley.foon.tan@intel.com>

diff --git a/arch/nios2/include/asm/cacheflush.h b/arch/nios2/include/asm/cacheflush.h
index 52abba973dc2adab1b56d70fd06486dacba0f336..55e383c173f776f35826d4d5d70b5af41f552a46 100644 (file)
--- a/arch/nios2/include/asm/cacheflush.h
+++ b/arch/nios2/include/asm/cacheflush.h
@@ -46,7 +46,9 @@ extern void copy_from_user_page(struct vm_area_struct *vma, struct page *page,
 extern void flush_dcache_range(unsigned long start, unsigned long end);
 extern void invalidate_dcache_range(unsigned long start, unsigned long end);
 
-#define flush_dcache_mmap_lock(mapping)                do { } while (0)
-#define flush_dcache_mmap_unlock(mapping)      do { } while (0)
+#define flush_dcache_mmap_lock(mapping) \
+       spin_lock_irq(&(mapping)->tree_lock)
+#define flush_dcache_mmap_unlock(mapping) \
+       spin_unlock_irq(&(mapping)->tree_lock)
 
 #endif /* _ASM_NIOS2_CACHEFLUSH_H */