Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1946103AbXBPUMi (ORCPT ); Fri, 16 Feb 2007 15:12:38 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1946107AbXBPUMi (ORCPT ); Fri, 16 Feb 2007 15:12:38 -0500 Received: from smtp.osdl.org ([65.172.181.24]:33434 "EHLO smtp.osdl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1946103AbXBPUMh (ORCPT ); Fri, 16 Feb 2007 15:12:37 -0500 Date: Fri, 16 Feb 2007 12:12:26 -0800 From: Andrew Morton To: Eric Van Hensbergen Cc: linux-kernel@vger.kernel.org, v9fs-developer@lists.sourceforge.net Subject: Re: [PATCH] 9p: add write-cache support to loose cache mode (take 3) Message-Id: <20070216121226.f2382a17.akpm@linux-foundation.org> In-Reply-To: <1171640221420-git-send-email-ericvh@gmail.com> References: <11715506591894-git-send-email-ericvh@gmail.com> <1171640221420-git-send-email-ericvh@gmail.com> X-Mailer: Sylpheed version 2.2.7 (GTK+ 2.8.17; x86_64-unknown-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1588 Lines: 53 On Fri, 16 Feb 2007 09:37:01 -0600 Eric Van Hensbergen wrote: > +static int v9fs_vfs_writepage(struct page *page, struct writeback_control *wbc) > +{ > + char *buffer = NULL; > + struct address_space *mapping = page->mapping; > + int retval = -EIO; > + loff_t offset = 0; > + pgoff_t end_index; > + int count = PAGE_CACHE_SIZE; > + struct file *filp = v9fs_find_file(page); > + struct inode *inode = mapping->host; > + > + dprintk(DEBUG_VFS, "page: %p\n", page); > + > + if ((!inode) || (!filp)) > + goto UnlockPage; > + > + end_index = inode->i_size >> PAGE_CACHE_SHIFT; > + > + /* complicated case at end of file */ > + if (page->index >= end_index) { > + /* things got complicated... */ > + count = inode->i_size & (PAGE_CACHE_SIZE - 1); > + if (page->index >= end_index + 1 || !count) > + return 0; /* truncated - don't care */ > + } > + > + buffer = kmap(page); > + offset = ((loff_t) page->index << PAGE_CACHE_SHIFT); > + page_cache_get(page); > + retval = v9fs_write(filp, NULL, buffer, count, &offset); > + > kunmap(page); > + > + UnlockPage: > unlock_page(page); > + page_cache_release(page); > + > return retval; > } The page_cache_get/release here aren't needed: lock_page suffices. Are you sure the page refcounting is right if the `goto UnlockPage' happens? Can that goto actually happen?? - 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/