Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754839AbbGIUsv (ORCPT ); Thu, 9 Jul 2015 16:48:51 -0400 Received: from smtp02.citrix.com ([66.165.176.63]:25531 "EHLO SMTP02.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754496AbbGIUnl (ORCPT ); Thu, 9 Jul 2015 16:43:41 -0400 X-IronPort-AV: E=Sophos;i="5.15,442,1432598400"; d="scan'208";a="282741510" From: Julien Grall To: CC: , , , , "Julien Grall" , Konrad Rzeszutek Wilk , Boris Ostrovsky , David Vrabel Subject: [PATCH v2 02/20] xen: Introduce a function to split a Linux page into Xen page Date: Thu, 9 Jul 2015 21:42:14 +0100 Message-ID: <1436474552-31789-3-git-send-email-julien.grall@citrix.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1436474552-31789-1-git-send-email-julien.grall@citrix.com> References: <1436474552-31789-1-git-send-email-julien.grall@citrix.com> MIME-Version: 1.0 Content-Type: text/plain X-DLP: MIA2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1578 Lines: 55 The Xen interface is always using 4KB page. This means that a Linux page may be split across multiple Xen page when the page granularity is not the same. This helper will break down a Linux page into 4KB chunk and call the helper on each of them. Signed-off-by: Julien Grall Cc: Konrad Rzeszutek Wilk Cc: Boris Ostrovsky Cc: David Vrabel --- Changes in v2: - Patch added --- include/xen/page.h | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/include/xen/page.h b/include/xen/page.h index 8ebd37b..b1f7722 100644 --- a/include/xen/page.h +++ b/include/xen/page.h @@ -39,4 +39,24 @@ struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS]; extern unsigned long xen_released_pages; +typedef int (*xen_pfn_fn_t)(struct page *page, unsigned long pfn, void *data); + +/* Break down the page in 4KB granularity and call fn foreach xen pfn */ +static inline int xen_apply_to_page(struct page *page, xen_pfn_fn_t fn, + void *data) +{ + unsigned long pfn = xen_page_to_pfn(page); + int i; + int ret; + + for (i = 0; i < XEN_PFN_PER_PAGE; i++, pfn++) { + ret = fn(page, pfn, data); + if (ret) + return ret; + } + + return ret; +} + + #endif /* _XEN_PAGE_H */ -- 2.1.4 -- 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/