From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f181.google.com (mail-pd0-f181.google.com [209.85.192.181]) by kanga.kvack.org (Postfix) with ESMTP id 9793C6B0036 for ; Mon, 10 Feb 2014 15:41:17 -0500 (EST) Received: by mail-pd0-f181.google.com with SMTP id y10so6549453pdj.40 for ; Mon, 10 Feb 2014 12:41:17 -0800 (PST) Received: from mga02.intel.com (mga02.intel.com. [134.134.136.20]) by mx.google.com with ESMTP id pg10si16605351pbb.54.2014.02.10.12.41.16 for ; Mon, 10 Feb 2014 12:41:16 -0800 (PST) From: "Kirill A. Shutemov" Subject: [PATCH 3/8] mm: do_fault(): extract to call vm_ops->do_fault() to separate function Date: Mon, 10 Feb 2014 22:41:01 +0200 Message-Id: <1392064866-11840-4-git-send-email-kirill.shutemov@linux.intel.com> In-Reply-To: <1392064866-11840-1-git-send-email-kirill.shutemov@linux.intel.com> References: <1392064866-11840-1-git-send-email-kirill.shutemov@linux.intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton , Mel Gorman , Rik van Riel Cc: Andi Kleen , Matthew Wilcox , Dave Hansen , linux-mm@kvack.org, "Kirill A. Shutemov" The patch extract code to vm_ops->do_fault() and basic error handling to separate function. The code will be reused. Signed-off-by: Kirill A. Shutemov --- mm/memory.c | 76 ++++++++++++++++++++++++++++++++++++------------------------- 1 file changed, 45 insertions(+), 31 deletions(-) diff --git a/mm/memory.c b/mm/memory.c index e626283089ca..d3317ac02a5b 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3286,6 +3286,37 @@ oom: return VM_FAULT_OOM; } +static int __do_fault(struct vm_area_struct *vma, unsigned long address, + pgoff_t pgoff, unsigned int flags, struct page **page) +{ + struct vm_fault vmf; + int ret; + + vmf.virtual_address = (void __user *)(address & PAGE_MASK); + vmf.pgoff = pgoff; + vmf.flags = flags; + vmf.page = NULL; + + ret = vma->vm_ops->fault(vma, &vmf); + if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE | VM_FAULT_RETRY))) + return ret; + + if (unlikely(PageHWPoison(vmf.page))) { + if (ret & VM_FAULT_LOCKED) + unlock_page(vmf.page); + page_cache_release(vmf.page); + return VM_FAULT_HWPOISON; + } + + if (unlikely(!(ret & VM_FAULT_LOCKED))) + lock_page(vmf.page); + else + VM_BUG_ON_PAGE(!PageLocked(vmf.page), vmf.page); + + *page = vmf.page; + return ret; +} + /* * do_fault() tries to create a new page mapping. It aggressively * tries to share with existing pages, but makes a separate copy if @@ -3305,12 +3336,11 @@ static int do_fault(struct mm_struct *mm, struct vm_area_struct *vma, { pte_t *page_table; spinlock_t *ptl; - struct page *page; + struct page *page, *fault_page; struct page *cow_page; pte_t entry; int anon = 0; struct page *dirty_page = NULL; - struct vm_fault vmf; int ret; int page_mkwrite = 0; @@ -3334,42 +3364,19 @@ static int do_fault(struct mm_struct *mm, struct vm_area_struct *vma, } else cow_page = NULL; - vmf.virtual_address = (void __user *)(address & PAGE_MASK); - vmf.pgoff = pgoff; - vmf.flags = flags; - vmf.page = NULL; - - ret = vma->vm_ops->fault(vma, &vmf); - if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE | - VM_FAULT_RETRY))) + ret = __do_fault(vma, address, pgoff, flags, &fault_page); + if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE | VM_FAULT_RETRY))) goto uncharge_out; - if (unlikely(PageHWPoison(vmf.page))) { - if (ret & VM_FAULT_LOCKED) - unlock_page(vmf.page); - ret = VM_FAULT_HWPOISON; - page_cache_release(vmf.page); - goto uncharge_out; - } - - /* - * For consistency in subsequent calls, make the faulted page always - * locked. - */ - if (unlikely(!(ret & VM_FAULT_LOCKED))) - lock_page(vmf.page); - else - VM_BUG_ON_PAGE(!PageLocked(vmf.page), vmf.page); - /* * Should we do an early C-O-W break? */ - page = vmf.page; + page = fault_page; if (flags & FAULT_FLAG_WRITE) { if (!(vma->vm_flags & VM_SHARED)) { page = cow_page; anon = 1; - copy_user_highpage(page, vmf.page, address, vma); + copy_user_highpage(page, fault_page, address, vma); __SetPageUptodate(page); } else { /* @@ -3378,8 +3385,15 @@ static int do_fault(struct mm_struct *mm, struct vm_area_struct *vma, * to become writable */ if (vma->vm_ops->page_mkwrite) { + struct vm_fault vmf; int tmp; + vmf.virtual_address = + (void __user *)(address & PAGE_MASK); + vmf.pgoff = pgoff; + vmf.flags = flags; + vmf.page = fault_page; + unlock_page(page); vmf.flags = FAULT_FLAG_WRITE|FAULT_FLAG_MKWRITE; tmp = vma->vm_ops->page_mkwrite(vma, &vmf); @@ -3469,9 +3483,9 @@ static int do_fault(struct mm_struct *mm, struct vm_area_struct *vma, if (vma->vm_file && !page_mkwrite) file_update_time(vma->vm_file); } else { - unlock_page(vmf.page); + unlock_page(fault_page); if (anon) - page_cache_release(vmf.page); + page_cache_release(fault_page); } return ret; -- 1.8.5.4 -- 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