From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx112.postini.com [74.125.245.112]) by kanga.kvack.org (Postfix) with SMTP id 1AE9E6B0037 for ; Thu, 14 Mar 2013 06:09:07 -0400 (EDT) Received: from /spool/local by e23smtp03.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 14 Mar 2013 20:02:25 +1000 Received: from d23relay05.au.ibm.com (d23relay05.au.ibm.com [9.190.235.152]) by d23dlp01.au.ibm.com (Postfix) with ESMTP id 58FF82CE804C for ; Thu, 14 Mar 2013 21:08:58 +1100 (EST) Received: from d23av02.au.ibm.com (d23av02.au.ibm.com [9.190.235.138]) by d23relay05.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r2E9u3HN63373328 for ; Thu, 14 Mar 2013 20:56:03 +1100 Received: from d23av02.au.ibm.com (loopback [127.0.0.1]) by d23av02.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r2EA8vbe026004 for ; Thu, 14 Mar 2013 21:08:57 +1100 From: Wanpeng Li Subject: [PATCH v2 1/4] introduce zero filled pages handler Date: Thu, 14 Mar 2013 18:08:14 +0800 Message-Id: <1363255697-19674-2-git-send-email-liwanp@linux.vnet.ibm.com> In-Reply-To: <1363255697-19674-1-git-send-email-liwanp@linux.vnet.ibm.com> References: <1363255697-19674-1-git-send-email-liwanp@linux.vnet.ibm.com> Sender: owner-linux-mm@kvack.org List-ID: To: Greg Kroah-Hartman , Andrew Morton Cc: Dan Magenheimer , Seth Jennings , Konrad Rzeszutek Wilk , Minchan Kim , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Wanpeng Li 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 | 26 ++++++++++++++++++++++++++ 1 files changed, 26 insertions(+), 0 deletions(-) diff --git a/drivers/staging/zcache/zcache-main.c b/drivers/staging/zcache/zcache-main.c index 328898e..b71e033 100644 --- a/drivers/staging/zcache/zcache-main.c +++ b/drivers/staging/zcache/zcache-main.c @@ -460,6 +460,32 @@ static void zcache_obj_free(struct tmem_obj *obj, struct tmem_pool *pool) kmem_cache_free(zcache_obj_cache, obj); } +static bool page_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_page(void *page) +{ + void *user_mem; + + 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, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org