From e215605417b87732c6debf65da6d953016a1e5bc Mon Sep 17 00:00:00 2001 From: Alex Elder Date: Wed, 22 May 2013 20:54:25 -0500 Subject: [PATCH] rbd: flush dcache after zeroing page data Neither zero_bio_chain() nor zero_pages() contains a call to flush caches after zeroing a portion of a page. This can cause problems on architectures that have caches that allow virtual address aliasing. This resolves: http://tracker.ceph.com/issues/4777 Signed-off-by: Alex Elder Reviewed-by: Josh Durgin --- drivers/block/rbd.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 291802c52c65..cb728a01a19f 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -1126,6 +1126,7 @@ static void zero_bio_chain(struct bio *chain, int start_ofs) buf = bvec_kmap_irq(bv, &flags); memset(buf + remainder, 0, bv->bv_len - remainder); + flush_dcache_page(bv->bv_page); bvec_kunmap_irq(buf, &flags); } pos += bv->bv_len; @@ -1158,6 +1159,7 @@ static void zero_pages(struct page **pages, u64 offset, u64 end) local_irq_save(flags); kaddr = kmap_atomic(*page); memset(kaddr + page_offset, 0, length); + flush_dcache_page(*page); kunmap_atomic(kaddr); local_irq_restore(flags); -- 2.20.1