diff options
author | Christoph Hellwig <hch@lst.de> | 2015-10-03 13:32:57 (GMT) |
---|---|---|
committer | Nicholas Bellinger <nab@linux-iscsi.org> | 2015-10-14 05:17:53 (GMT) |
commit | 13a83fc9096dfaf2a7f4671b5777780bbe1d4a30 (patch) | |
tree | 2874119928c790fb2c1706a12cbc9ff305aa9644 /fs/ocfs2 | |
parent | ea9ed9cff47e7932925982c8fdaf2d4d1708884f (diff) | |
download | linux-13a83fc9096dfaf2a7f4671b5777780bbe1d4a30.tar.xz |
ocfs2/cluster: move locking into attribute store methods
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 <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Diffstat (limited to 'fs/ocfs2')
-rw-r--r-- | fs/ocfs2/cluster/nodemanager.c | 54 |
1 files 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 = { |