From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with SMTP id B67DC6B004F for ; Tue, 9 Jun 2009 05:01:24 -0400 (EDT) Date: Tue, 9 Jun 2009 17:31:59 +0800 From: Wu Fengguang Subject: [PATCH] [11/15] HWPOISON: Refactor truncate to allow direct truncating of page v3 Message-ID: <20090609093159.GA8244@localhost> References: <200906041128.112757038@firstfloor.org> <20090604212823.16F901D0293@basil.firstfloor.org> <20090609091821.GA16940@wotan.suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090609091821.GA16940@wotan.suse.de> Sender: owner-linux-mm@kvack.org To: Nick Piggin Cc: Andi Kleen , "akpm@linux-foundation.org" , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" List-ID: On Tue, Jun 09, 2009 at 05:18:21PM +0800, Nick Piggin wrote: > On Thu, Jun 04, 2009 at 11:28:23PM +0200, Andi Kleen wrote: > > > > From: Nick Piggin > > > > Extract out truncate_inode_page() out of the truncate path so that > > it can be used by memory-failure.c > > > > [AK: description, headers, fix typos] > > v2: Some white space changes from Fengguang Wu > > > > Signed-off-by: Andi Kleen > > Thank you muchly :) Seems the description is still missing? Something > like the below? > > Signed-off-by: Nick Piggin Andi is on vocation, so let me do the updates :) Thanks, Fengguang --- HWPOISON: Refactor truncate to allow direct truncating of page v3 From: Nick Piggin Extract out truncate_inode_page() out of the truncate path so that it can be used by memory-failure.c [AK: description, headers, fix typos] v2: Some white space changes from Fengguang Wu v3: add comments Signed-off-by: Nick Piggin Signed-off-by: Andi Kleen --- include/linux/mm.h | 2 ++ mm/truncate.c | 34 ++++++++++++++++++++++------------ 2 files changed, 24 insertions(+), 12 deletions(-) --- linux.orig/mm/truncate.c +++ linux/mm/truncate.c @@ -135,6 +135,26 @@ invalidate_complete_page(struct address_ return ret; } +/* + * Remove one page from its pagecache mapping. The page must be locked. + * This does not truncate the file on disk, it performs the pagecache + * side of the truncate operation. Dirty data will be discarded, and + * concurrent page references are ignored. + * + * Generic mm/fs code cannot call this on filesystem metadata mappings + * because those can assume that a page reference is enough to pin the + * page to its mapping. + */ +void truncate_inode_page(struct address_space *mapping, struct page *page) +{ + if (page_mapped(page)) { + unmap_mapping_range(mapping, + (loff_t)page->index << PAGE_CACHE_SHIFT, + PAGE_CACHE_SIZE, 0); + } + truncate_complete_page(mapping, page); +} + /** * truncate_inode_pages - truncate range of pages specified by start & end byte offsets * @mapping: mapping to truncate @@ -196,12 +216,7 @@ void truncate_inode_pages_range(struct a unlock_page(page); continue; } - if (page_mapped(page)) { - unmap_mapping_range(mapping, - (loff_t)page_index<index<index > next) next = page->index; next++; - truncate_complete_page(mapping, page); unlock_page(page); } pagevec_release(&pvec); --- linux.orig/include/linux/mm.h +++ linux/include/linux/mm.h @@ -808,6 +808,8 @@ static inline void unmap_shared_mapping_ extern int vmtruncate(struct inode * inode, loff_t offset); extern int vmtruncate_range(struct inode * inode, loff_t offset, loff_t end); +void truncate_inode_page(struct address_space *mapping, struct page *page); + #ifdef CONFIG_MMU extern int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long address, int write_access); -- 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