From 2d4dc890b5c8fabd818a8586607e6843c4375e62 Mon Sep 17 00:00:00 2001 From: Ilya Loginov Date: Thu, 26 Nov 2009 09:16:19 +0100 Subject: block: add helpers to run flush_dcache_page() against a bio and a request's pages Mtdblock driver doesn't call flush_dcache_page for pages in request. So, this causes problems on architectures where the icache doesn't fill from the dcache or with dcache aliases. The patch fixes this. The ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE symbol was introduced to avoid pointless empty cache-thrashing loops on architectures for which flush_dcache_page() is a no-op. Every architecture was provided with this flush pages on architectires where ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE is equal 1 or do nothing otherwise. See "fix mtd_blkdevs problem with caches on some architectures" discussion on LKML for more information. Signed-off-by: Ilya Loginov Cc: Ingo Molnar Cc: David Woodhouse Cc: Peter Horton Cc: "Ed L. Cashin" Signed-off-by: Jens Axboe --- drivers/mtd/mtd_blkdevs.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers') diff --git a/drivers/mtd/mtd_blkdevs.c b/drivers/mtd/mtd_blkdevs.c index 8ca17a3e96ea..64e2b379a350 100644 --- a/drivers/mtd/mtd_blkdevs.c +++ b/drivers/mtd/mtd_blkdevs.c @@ -59,12 +59,14 @@ static int do_blktrans_request(struct mtd_blktrans_ops *tr, for (; nsect > 0; nsect--, block++, buf += tr->blksize) if (tr->readsect(dev, block, buf)) return -EIO; + rq_flush_dcache_pages(req); return 0; case WRITE: if (!tr->writesect) return -EIO; + rq_flush_dcache_pages(req); for (; nsect > 0; nsect--, block++, buf += tr->blksize) if (tr->writesect(dev, block, buf)) return -EIO; -- cgit v1.2.2