From patchwork Fri Nov 4 04:25:10 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Kara X-Patchwork-Id: 9411845 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id BA14E60585 for ; Fri, 4 Nov 2016 04:25:39 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A8C022ACA2 for ; Fri, 4 Nov 2016 04:25:39 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9C3312AFF7; Fri, 4 Nov 2016 04:25:39 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.9 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from ml01.01.org (ml01.01.org [198.145.21.10]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 3A5582ACA2 for ; Fri, 4 Nov 2016 04:25:39 +0000 (UTC) Received: from [127.0.0.1] (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id 30B3281D9D; Thu, 3 Nov 2016 21:25:28 -0700 (PDT) X-Original-To: linux-nvdimm@lists.01.org Delivered-To: linux-nvdimm@lists.01.org Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 746C781D74 for ; Thu, 3 Nov 2016 21:25:26 -0700 (PDT) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 2CFC1ADB8; Fri, 4 Nov 2016 04:25:26 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id B2C7C1E0FD4; Fri, 4 Nov 2016 05:25:20 +0100 (CET) From: Jan Kara To: Subject: [PATCH 14/21] mm: Use vmf->page during WP faults Date: Fri, 4 Nov 2016 05:25:10 +0100 Message-Id: <1478233517-3571-15-git-send-email-jack@suse.cz> X-Mailer: git-send-email 2.6.6 In-Reply-To: <1478233517-3571-1-git-send-email-jack@suse.cz> References: <1478233517-3571-1-git-send-email-jack@suse.cz> X-BeenThere: linux-nvdimm@lists.01.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: "Linux-nvdimm developer list." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jan Kara , linux-nvdimm@lists.01.org, linux-fsdevel@vger.kernel.org, Andrew Morton , "Kirill A. Shutemov" MIME-Version: 1.0 Errors-To: linux-nvdimm-bounces@lists.01.org Sender: "Linux-nvdimm" X-Virus-Scanned: ClamAV using ClamSMTP So far we set vmf->page during WP faults only when we needed to pass it to the ->page_mkwrite handler. Set it in all the cases now and use that instead of passing page pointer explicitly around. Reviewed-by: Ross Zwisler Signed-off-by: Jan Kara Acked-by: Kirill A. Shutemov --- mm/memory.c | 58 +++++++++++++++++++++++++++++----------------------------- 1 file changed, 29 insertions(+), 29 deletions(-) diff --git a/mm/memory.c b/mm/memory.c index c89f99c270bc..e278a8a6ccc7 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2103,11 +2103,12 @@ static void fault_dirty_shared_page(struct vm_area_struct *vma, * case, all we need to do here is to mark the page as writable and update * any related book-keeping. */ -static inline int wp_page_reuse(struct vm_fault *vmf, struct page *page, +static inline int wp_page_reuse(struct vm_fault *vmf, int page_mkwrite, int dirty_shared) __releases(vmf->ptl) { struct vm_area_struct *vma = vmf->vma; + struct page *page = vmf->page; pte_t entry; /* * Clear the pages cpupid information as the existing @@ -2151,10 +2152,11 @@ static inline int wp_page_reuse(struct vm_fault *vmf, struct page *page, * held to the old page, as well as updating the rmap. * - In any case, unlock the PTL and drop the reference we took to the old page. */ -static int wp_page_copy(struct vm_fault *vmf, struct page *old_page) +static int wp_page_copy(struct vm_fault *vmf) { struct vm_area_struct *vma = vmf->vma; struct mm_struct *mm = vma->vm_mm; + struct page *old_page = vmf->page; struct page *new_page = NULL; pte_t entry; int page_copied = 0; @@ -2306,26 +2308,25 @@ static int wp_pfn_shared(struct vm_fault *vmf) return 0; } } - return wp_page_reuse(vmf, NULL, 0, 0); + return wp_page_reuse(vmf, 0, 0); } -static int wp_page_shared(struct vm_fault *vmf, struct page *old_page) +static int wp_page_shared(struct vm_fault *vmf) __releases(vmf->ptl) { struct vm_area_struct *vma = vmf->vma; int page_mkwrite = 0; - get_page(old_page); + get_page(vmf->page); if (vma->vm_ops->page_mkwrite) { int tmp; pte_unmap_unlock(vmf->pte, vmf->ptl); - vmf->page = old_page; tmp = do_page_mkwrite(vmf); if (unlikely(!tmp || (tmp & (VM_FAULT_ERROR | VM_FAULT_NOPAGE)))) { - put_page(old_page); + put_page(vmf->page); return tmp; } /* @@ -2337,15 +2338,15 @@ static int wp_page_shared(struct vm_fault *vmf, struct page *old_page) vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd, vmf->address, &vmf->ptl); if (!pte_same(*vmf->pte, vmf->orig_pte)) { - unlock_page(old_page); + unlock_page(vmf->page); pte_unmap_unlock(vmf->pte, vmf->ptl); - put_page(old_page); + put_page(vmf->page); return 0; } page_mkwrite = 1; } - return wp_page_reuse(vmf, old_page, page_mkwrite, 1); + return wp_page_reuse(vmf, page_mkwrite, 1); } /* @@ -2370,10 +2371,9 @@ static int do_wp_page(struct vm_fault *vmf) __releases(vmf->ptl) { struct vm_area_struct *vma = vmf->vma; - struct page *old_page; - old_page = vm_normal_page(vma, vmf->address, vmf->orig_pte); - if (!old_page) { + vmf->page = vm_normal_page(vma, vmf->address, vmf->orig_pte); + if (!vmf->page) { /* * VM_MIXEDMAP !pfn_valid() case, or VM_SOFTDIRTY clear on a * VM_PFNMAP VMA. @@ -2386,30 +2386,30 @@ static int do_wp_page(struct vm_fault *vmf) return wp_pfn_shared(vmf); pte_unmap_unlock(vmf->pte, vmf->ptl); - return wp_page_copy(vmf, old_page); + return wp_page_copy(vmf); } /* * Take out anonymous pages first, anonymous shared vmas are * not dirty accountable. */ - if (PageAnon(old_page) && !PageKsm(old_page)) { + if (PageAnon(vmf->page) && !PageKsm(vmf->page)) { int total_mapcount; - if (!trylock_page(old_page)) { - get_page(old_page); + if (!trylock_page(vmf->page)) { + get_page(vmf->page); pte_unmap_unlock(vmf->pte, vmf->ptl); - lock_page(old_page); + lock_page(vmf->page); vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd, vmf->address, &vmf->ptl); if (!pte_same(*vmf->pte, vmf->orig_pte)) { - unlock_page(old_page); + unlock_page(vmf->page); pte_unmap_unlock(vmf->pte, vmf->ptl); - put_page(old_page); + put_page(vmf->page); return 0; } - put_page(old_page); + put_page(vmf->page); } - if (reuse_swap_page(old_page, &total_mapcount)) { + if (reuse_swap_page(vmf->page, &total_mapcount)) { if (total_mapcount == 1) { /* * The page is all ours. Move it to @@ -2418,24 +2418,24 @@ static int do_wp_page(struct vm_fault *vmf) * Protected against the rmap code by * the page lock. */ - page_move_anon_rmap(old_page, vma); + page_move_anon_rmap(vmf->page, vma); } - unlock_page(old_page); - return wp_page_reuse(vmf, old_page, 0, 0); + unlock_page(vmf->page); + return wp_page_reuse(vmf, 0, 0); } - unlock_page(old_page); + unlock_page(vmf->page); } else if (unlikely((vma->vm_flags & (VM_WRITE|VM_SHARED)) == (VM_WRITE|VM_SHARED))) { - return wp_page_shared(vmf, old_page); + return wp_page_shared(vmf); } /* * Ok, we need to copy. Oh, well.. */ - get_page(old_page); + get_page(vmf->page); pte_unmap_unlock(vmf->pte, vmf->ptl); - return wp_page_copy(vmf, old_page); + return wp_page_copy(vmf); } static void unmap_mapping_range_vma(struct vm_area_struct *vma,