From patchwork Sat Oct 3 13:32:57 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 7321081 Return-Path: X-Original-To: patchwork-ocfs2-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 27800BFD59 for ; Sat, 3 Oct 2015 13:38:27 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 2EC282082B for ; Sat, 3 Oct 2015 13:38:26 +0000 (UTC) Received: from aserp1040.oracle.com (aserp1040.oracle.com [141.146.126.69]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E744320880 for ; Sat, 3 Oct 2015 13:38:24 +0000 (UTC) Received: from userv0022.oracle.com (userv0022.oracle.com [156.151.31.74]) by aserp1040.oracle.com (Sentrion-MTA-4.3.2/Sentrion-MTA-4.3.2) with ESMTP id t93DcIcb007309 (version=TLSv1 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Sat, 3 Oct 2015 13:38:18 GMT Received: from oss.oracle.com (oss-old-reserved.oracle.com [137.254.22.2]) by userv0022.oracle.com (8.13.8/8.13.8) with ESMTP id t93DcHo2001543 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Sat, 3 Oct 2015 13:38:18 GMT Received: from localhost ([127.0.0.1] helo=lb-oss.oracle.com) by oss.oracle.com with esmtp (Exim 4.63) (envelope-from ) id 1ZiN0z-0008QZ-NS; Sat, 03 Oct 2015 06:38:17 -0700 Received: from aserv0021.oracle.com ([141.146.126.233]) by oss.oracle.com with esmtp (Exim 4.63) (envelope-from ) id 1ZiN0h-0008K7-Ou for ocfs2-devel@oss.oracle.com; Sat, 03 Oct 2015 06:38:00 -0700 Received: from aserp1020.oracle.com (aserp1020.oracle.com [141.146.126.67]) by aserv0021.oracle.com (8.13.8/8.13.8) with ESMTP id t93Dbx6P020924 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Sat, 3 Oct 2015 13:37:59 GMT Received: from userp2040.oracle.com (userp2040.oracle.com [156.151.31.90]) by aserp1020.oracle.com (Sentrion-MTA-4.3.2/Sentrion-MTA-4.3.2) with ESMTP id t93DbwSh018479 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO) for ; Sat, 3 Oct 2015 13:37:59 GMT Received: from pps.filterd (userp2040.oracle.com [127.0.0.1]) by userp2040.oracle.com (8.15.0.59/8.15.0.59) with SMTP id t93DYUW9045237 for ; Sat, 3 Oct 2015 13:37:58 GMT Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) by userp2040.oracle.com with ESMTP id 1xa5my35tu-1 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Sat, 03 Oct 2015 13:37:58 +0000 Received: from [83.175.99.196] (helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZiN0Z-0003aE-5u; Sat, 03 Oct 2015 13:37:51 +0000 From: Christoph Hellwig To: Joel Becker , Andrew Morton , Nicholas Bellinger Date: Sat, 3 Oct 2015 15:32:57 +0200 Message-Id: <1443879179-22280-22-git-send-email-hch@lst.de> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1443879179-22280-1-git-send-email-hch@lst.de> References: <1443879179-22280-1-git-send-email-hch@lst.de> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org See http://www.infradead.org/rpr.html X-ServerName: bombadil.infradead.org X-Proofpoint-Virus-Version: vendor=nai engine=5700 definitions=7942 signatures=670638 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1507310000 definitions=main-1510030224 Cc: linux-usb@vger.kernel.org, netdev@vger.kernel.org, Pratyush Anand , Pantelis Antoniou , Felipe Balbi , cluster-devel@redhat.com, Tejun Heo , target-devel@vger.kernel.org, Andrzej Pietrasiewicz , ocfs2-devel@oss.oracle.com Subject: [Ocfs2-devel] [PATCH 21/23] ocfs2/cluster: move locking into attribute store methods X-BeenThere: ocfs2-devel@oss.oracle.com X-Mailman-Version: 2.1.9 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: ocfs2-devel-bounces@oss.oracle.com Errors-To: ocfs2-devel-bounces@oss.oracle.com X-Source-IP: userv0022.oracle.com [156.151.31.74] X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The test and separate set bit scheme was racy to start with, so move to do a test_and_set_bit after doing the earlier error checks inside the actual store methods. Also remove the locking for the local attribute which already has a different scheme to synchronize. Signed-off-by: Christoph Hellwig --- fs/ocfs2/cluster/nodemanager.c | 54 +++++++++++++++--------------------------- 1 file changed, 19 insertions(+), 35 deletions(-) diff --git a/fs/ocfs2/cluster/nodemanager.c b/fs/ocfs2/cluster/nodemanager.c index 441c84e..7a398f6 100644 --- a/fs/ocfs2/cluster/nodemanager.c +++ b/fs/ocfs2/cluster/nodemanager.c @@ -188,7 +188,6 @@ enum { O2NM_NODE_ATTR_NUM = 0, O2NM_NODE_ATTR_PORT, O2NM_NODE_ATTR_ADDRESS, - O2NM_NODE_ATTR_LOCAL, }; static ssize_t o2nm_node_num_write(struct o2nm_node *node, const char *page, @@ -197,6 +196,7 @@ static ssize_t o2nm_node_num_write(struct o2nm_node *node, const char *page, struct o2nm_cluster *cluster = to_o2nm_cluster_from_node(node); unsigned long tmp; char *p = (char *)page; + int ret = 0; tmp = simple_strtoul(p, &p, 0); if (!p || (*p && (*p != '\n'))) @@ -215,15 +215,18 @@ static ssize_t o2nm_node_num_write(struct o2nm_node *node, const char *page, write_lock(&cluster->cl_nodes_lock); if (cluster->cl_nodes[tmp]) - p = NULL; + ret = -EEXIST; + else if (test_and_set_bit(O2NM_NODE_ATTR_NUM, + &node->nd_set_attributes)) + ret = -EBUSY; else { cluster->cl_nodes[tmp] = node; node->nd_num = tmp; set_bit(tmp, cluster->cl_nodes_bitmap); } write_unlock(&cluster->cl_nodes_lock); - if (p == NULL) - return -EEXIST; + if (ret) + return ret; return count; } @@ -247,6 +250,8 @@ static ssize_t o2nm_node_ipv4_port_write(struct o2nm_node *node, if (tmp >= (u16)-1) return -ERANGE; + if (test_and_set_bit(O2NM_NODE_ATTR_PORT, &node->nd_set_attributes)) + return -EBUSY; node->nd_ipv4_port = htons(tmp); return count; @@ -282,6 +287,9 @@ static ssize_t o2nm_node_ipv4_address_write(struct o2nm_node *node, write_lock(&cluster->cl_nodes_lock); if (o2nm_node_ip_tree_lookup(cluster, ipv4_addr, &p, &parent)) ret = -EEXIST; + else if (test_and_set_bit(O2NM_NODE_ATTR_ADDRESS, + &node->nd_set_attributes)) + ret = -EBUSY; else { rb_link_node(&node->nd_ip_node, parent, p); rb_insert_color(&node->nd_ip_node, &cluster->cl_node_ip_tree); @@ -388,24 +396,13 @@ static struct o2nm_node_attribute o2nm_node_attr_local = { }; static struct configfs_attribute *o2nm_node_attrs[] = { - [O2NM_NODE_ATTR_NUM] = &o2nm_node_attr_num.attr, - [O2NM_NODE_ATTR_PORT] = &o2nm_node_attr_ipv4_port.attr, - [O2NM_NODE_ATTR_ADDRESS] = &o2nm_node_attr_ipv4_address.attr, - [O2NM_NODE_ATTR_LOCAL] = &o2nm_node_attr_local.attr, + &o2nm_node_attr_num.attr, + &o2nm_node_attr_ipv4_port.attr, + &o2nm_node_attr_ipv4_address.attr, + &o2nm_node_attr_local.attr, NULL, }; -static int o2nm_attr_index(struct configfs_attribute *attr) -{ - int i; - for (i = 0; i < ARRAY_SIZE(o2nm_node_attrs); i++) { - if (attr == o2nm_node_attrs[i]) - return i; - } - BUG(); - return 0; -} - static ssize_t o2nm_node_show(struct config_item *item, struct configfs_attribute *attr, char *page) @@ -427,24 +424,11 @@ static ssize_t o2nm_node_store(struct config_item *item, struct o2nm_node *node = to_o2nm_node(item); struct o2nm_node_attribute *o2nm_node_attr = container_of(attr, struct o2nm_node_attribute, attr); - ssize_t ret; - int attr_index = o2nm_attr_index(attr); - if (o2nm_node_attr->store == NULL) { - ret = -EINVAL; - goto out; - } - - if (test_bit(attr_index, &node->nd_set_attributes)) - return -EBUSY; - - ret = o2nm_node_attr->store(node, page, count); - if (ret < count) - goto out; + if (o2nm_node_attr->store == NULL) + return -EINVAL; - set_bit(attr_index, &node->nd_set_attributes); -out: - return ret; + return o2nm_node_attr->store(node, page, count); } static struct configfs_item_operations o2nm_node_item_ops = {