sh: Add a PG_dcache_dirty sanity check in kmap_coherent().

This plugs in a BUG_ON() in kmap_coherent() for PG_dcache_dirty pages
to catch when things go horribly wrong. Copied from the MIPS
implementation.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

diff --git a/arch/sh/mm/pg-mmu.c b/arch/sh/mm/pg-mmu.c
index 8602f68af4c869748951ccbd1109f2cf78833ba0..32351206edd31d49da645b89816d23928b4a94f7 100644 (file)
--- a/arch/sh/mm/pg-mmu.c
+++ b/arch/sh/mm/pg-mmu.c
@@ -37,6 +37,8 @@ static inline void *kmap_coherent(struct page *page, unsigned long addr)
        unsigned long vaddr, flags;
        pte_t pte;
 
+       BUG_ON(test_bit(PG_dcache_dirty, &page->flags));
+
        inc_preempt_count();
 
        idx = (addr & current_cpu_data.dcache.alias_mask) >> PAGE_SHIFT;