Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759997Ab3DBCqh (ORCPT ); Mon, 1 Apr 2013 22:46:37 -0400 Received: from e28smtp05.in.ibm.com ([122.248.162.5]:55766 "EHLO e28smtp05.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755073Ab3DBCqf (ORCPT ); Mon, 1 Apr 2013 22:46:35 -0400 From: Wanpeng Li To: Greg Kroah-Hartman Cc: Andrew Morton , Dan Magenheimer , Seth Jennings , Konrad Rzeszutek Wilk , Minchan Kim , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Geert Uytterhoeven , Fengguang Wu , Wanpeng Li Subject: [PATCH v5 1/8] staging: zcache: introduce zero-filled pages handler Date: Tue, 2 Apr 2013 10:46:13 +0800 Message-Id: <1364870780-16296-2-git-send-email-liwanp@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.5.4 In-Reply-To: <1364870780-16296-1-git-send-email-liwanp@linux.vnet.ibm.com> References: <1364870780-16296-1-git-send-email-liwanp@linux.vnet.ibm.com> X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13040202-8256-0000-0000-000006E46E3B Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1506 Lines: 54 Introduce zero-filled pages handler to capture and handle zero pages. Acked-by: Dan Magenheimer Signed-off-by: Wanpeng Li --- drivers/staging/zcache/zcache-main.c | 27 +++++++++++++++++++++++++++ 1 files changed, 27 insertions(+), 0 deletions(-) diff --git a/drivers/staging/zcache/zcache-main.c b/drivers/staging/zcache/zcache-main.c index 7a6dd96..a0578d1 100644 --- a/drivers/staging/zcache/zcache-main.c +++ b/drivers/staging/zcache/zcache-main.c @@ -277,6 +277,33 @@ static void zcache_obj_free(struct tmem_obj *obj, struct tmem_pool *pool) kmem_cache_free(zcache_obj_cache, obj); } +static bool page_is_zero_filled(void *ptr) +{ + unsigned int pos; + unsigned long *page; + + page = (unsigned long *)ptr; + + for (pos = 0; pos < PAGE_SIZE / sizeof(*page); pos++) { + if (page[pos]) + return false; + } + + return true; +} + +static void handle_zero_filled_page(void *p) +{ + void *user_mem; + struct page *page = (struct page *)p; + + user_mem = kmap_atomic(page); + memset(user_mem, 0, PAGE_SIZE); + kunmap_atomic(user_mem); + + flush_dcache_page(page); +} + static struct tmem_hostops zcache_hostops = { .obj_alloc = zcache_obj_alloc, .obj_free = zcache_obj_free, -- 1.7.7.6 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/