From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754698Ab0FAT7J (ORCPT ); Tue, 1 Jun 2010 15:59:09 -0400 Received: from mx1.redhat.com ([209.132.183.28]:1874 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751171Ab0FAT7H (ORCPT ); Tue, 1 Jun 2010 15:59:07 -0400 Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells Subject: [PATCH] FS-Cache: Remove unneeded null checks To: torvalds@osdl.org, akpm@linux-foundation.org Cc: linux-cachefs@redhat.com, linux-kernel@vger.kernel.org, Dan Carpenter , David Howells Date: Tue, 01 Jun 2010 20:58:22 +0100 Message-ID: <20100601195822.8452.90732.stgit@warthog.procyon.org.uk> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dan Carpenter fscache_write_op() makes unnecessary checks of the page variable to see if it is NULL. It can't be NULL at those points as the kernel would already have crashed a little higher up where we examined page->index. Furthermore, unless radix_tree_gang_lookup_tag() can return 1 but no page, a NULL pointer crash should not be encountered there as we can only get there if r_t_g_l_t() returned 1. Signed-off-by: Dan Carpenter Signed-off-by: David Howells --- fs/fscache/page.c | 36 ++++++++++++++++-------------------- 1 files changed, 16 insertions(+), 20 deletions(-) diff --git a/fs/fscache/page.c b/fs/fscache/page.c index 9461617..5b9b00a 100644 --- a/fs/fscache/page.c +++ b/fs/fscache/page.c @@ -710,30 +710,26 @@ static void fscache_write_op(struct fscache_operation *_op) goto superseded; } - if (page) { - radix_tree_tag_set(&cookie->stores, page->index, - FSCACHE_COOKIE_STORING_TAG); - radix_tree_tag_clear(&cookie->stores, page->index, - FSCACHE_COOKIE_PENDING_TAG); - } + radix_tree_tag_set(&cookie->stores, page->index, + FSCACHE_COOKIE_STORING_TAG); + radix_tree_tag_clear(&cookie->stores, page->index, + FSCACHE_COOKIE_PENDING_TAG); spin_unlock(&cookie->stores_lock); spin_unlock(&object->lock); - if (page) { - fscache_set_op_state(&op->op, "Store"); - fscache_stat(&fscache_n_store_pages); - fscache_stat(&fscache_n_cop_write_page); - ret = object->cache->ops->write_page(op, page); - fscache_stat_d(&fscache_n_cop_write_page); - fscache_set_op_state(&op->op, "EndWrite"); - fscache_end_page_write(object, page); - if (ret < 0) { - fscache_set_op_state(&op->op, "Abort"); - fscache_abort_object(object); - } else { - fscache_enqueue_operation(&op->op); - } + fscache_set_op_state(&op->op, "Store"); + fscache_stat(&fscache_n_store_pages); + fscache_stat(&fscache_n_cop_write_page); + ret = object->cache->ops->write_page(op, page); + fscache_stat_d(&fscache_n_cop_write_page); + fscache_set_op_state(&op->op, "EndWrite"); + fscache_end_page_write(object, page); + if (ret < 0) { + fscache_set_op_state(&op->op, "Abort"); + fscache_abort_object(object); + } else { + fscache_enqueue_operation(&op->op); } _leave("");