Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934504Ab3CNRtP (ORCPT ); Thu, 14 Mar 2013 13:49:15 -0400 Received: from mga02.intel.com ([134.134.136.20]:54841 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758110Ab3CNRtM (ORCPT ); Thu, 14 Mar 2013 13:49:12 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.84,845,1355126400"; d="scan'208";a="302267164" From: "Kirill A. Shutemov" To: Andrea Arcangeli , Andrew Morton , Al Viro , Hugh Dickins Cc: Wu Fengguang , Jan Kara , Mel Gorman , linux-mm@kvack.org, Andi Kleen , Matthew Wilcox , "Kirill A. Shutemov" , Hillf Danton , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" Subject: [PATCHv2, RFC 02/30] mm: implement zero_huge_user_segment and friends Date: Thu, 14 Mar 2013 19:50:07 +0200 Message-Id: <1363283435-7666-3-git-send-email-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1363283435-7666-1-git-send-email-kirill.shutemov@linux.intel.com> References: <1363283435-7666-1-git-send-email-kirill.shutemov@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2607 Lines: 83 From: "Kirill A. Shutemov" Let's add helpers to clear huge page segment(s). They provide the same functionallity as zero_user_segment{,s} and zero_user, but for huge pages. Signed-off-by: Kirill A. Shutemov --- include/linux/mm.h | 15 +++++++++++++++ mm/memory.c | 26 ++++++++++++++++++++++++++ 2 files changed, 41 insertions(+) diff --git a/include/linux/mm.h b/include/linux/mm.h index 5b7fd4e..df83ab9 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1731,6 +1731,21 @@ extern void dump_page(struct page *page); extern void clear_huge_page(struct page *page, unsigned long addr, unsigned int pages_per_huge_page); +extern void zero_huge_user_segment(struct page *page, + unsigned start, unsigned end); +static inline void zero_huge_user_segments(struct page *page, + unsigned start1, unsigned end1, + unsigned start2, unsigned end2) +{ + zero_huge_user_segment(page, start1, end1); + zero_huge_user_segment(page, start2, end2); +} +static inline void zero_huge_user(struct page *page, + unsigned start, unsigned len) +{ + zero_huge_user_segment(page, start, start+len); +} + extern void copy_user_huge_page(struct page *dst, struct page *src, unsigned long addr, struct vm_area_struct *vma, unsigned int pages_per_huge_page); diff --git a/mm/memory.c b/mm/memory.c index 494526a..98c25dd 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -4213,6 +4213,32 @@ void clear_huge_page(struct page *page, } } +void zero_huge_user_segment(struct page *page, unsigned start, unsigned end) +{ + int i; + + BUG_ON(end < start); + + might_sleep(); + + if (start == end) + return; + + /* start and end are on the same small page */ + if ((start & PAGE_MASK) == ((end - 1) & PAGE_MASK)) + return zero_user_segment(page + (start >> PAGE_SHIFT), + start & ~PAGE_MASK, + ((end - 1) & ~PAGE_MASK) + 1); + + zero_user_segment(page + (start >> PAGE_SHIFT), + start & ~PAGE_MASK, PAGE_SIZE); + for (i = (start >> PAGE_SHIFT) + 1; i < (end >> PAGE_SHIFT) - 1; i++) { + cond_resched(); + clear_highpage(page + i); + } + zero_user_segment(page + i, 0, ((end - 1) & ~PAGE_MASK) + 1); +} + static void copy_user_gigantic_page(struct page *dst, struct page *src, unsigned long addr, struct vm_area_struct *vma, -- 1.7.10.4 -- 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/