return err;
}
-/*
- * And here should be modules and kernel interface
- * (Just smiley confuses emacs :-)
+static int find_free_cb(int id, void *ptr, void *data)
+{
+ struct nbd_device *nbd = ptr;
+ struct nbd_device **found = data;
+
+ if (!refcount_read(&nbd->config_refs)) {
+ *found = nbd;
+ return 1;
+ }
+ return 0;
+}
+
+/* Netlink interface. */
+static struct nla_policy nbd_attr_policy[NBD_ATTR_MAX + 1] = {
+ [NBD_ATTR_INDEX] = { .type = NLA_U32 },
+ [NBD_ATTR_SIZE_BYTES] = { .type = NLA_U64 },
+ [NBD_ATTR_BLOCK_SIZE_BYTES] = { .type = NLA_U64 },
+ [NBD_ATTR_TIMEOUT] = { .type = NLA_U64 },
+ [NBD_ATTR_SERVER_FLAGS] = { .type = NLA_U64 },
+ [NBD_ATTR_CLIENT_FLAGS] = { .type = NLA_U64 },
+ [NBD_ATTR_SOCKETS] = { .type = NLA_NESTED},
+ [NBD_ATTR_DEAD_CONN_TIMEOUT] = { .type = NLA_U64 },
+ [NBD_ATTR_DEVICE_LIST] = { .type = NLA_NESTED},
+};
+
+static struct nla_policy nbd_sock_policy[NBD_SOCK_MAX + 1] = {
+ [NBD_SOCK_FD] = { .type = NLA_U32 },
+};
+
+/* We don't use this right now since we don't parse the incoming list, but we
+ * still want it here so userspace knows what to expect.
*/
- nbd_sock_policy);
+static struct nla_policy __attribute__((unused))
+nbd_device_policy[NBD_DEVICE_ATTR_MAX + 1] = {
+ [NBD_DEVICE_INDEX] = { .type = NLA_U32 },
+ [NBD_DEVICE_CONNECTED] = { .type = NLA_U8 },
+};
+
+static int nbd_genl_connect(struct sk_buff *skb, struct genl_info *info)
+{
+ struct nbd_device *nbd = NULL;
+ struct nbd_config *config;
+ int index = -1;
+ int ret;
+ bool put_dev = false;
+
+ if (!netlink_capable(skb, CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (info->attrs[NBD_ATTR_INDEX])
+ index = nla_get_u32(info->attrs[NBD_ATTR_INDEX]);
+ if (!info->attrs[NBD_ATTR_SOCKETS]) {
+ printk(KERN_ERR "nbd: must specify at least one socket\n");
+ return -EINVAL;
+ }
+ if (!info->attrs[NBD_ATTR_SIZE_BYTES]) {
+ printk(KERN_ERR "nbd: must specify a size in bytes for the device\n");
+ return -EINVAL;
+ }
+again:
+ mutex_lock(&nbd_index_mutex);
+ if (index == -1) {
+ ret = idr_for_each(&nbd_index_idr, &find_free_cb, &nbd);
+ if (ret == 0) {
+ int new_index;
+ new_index = nbd_dev_add(-1);
+ if (new_index < 0) {
+ mutex_unlock(&nbd_index_mutex);
+ printk(KERN_ERR "nbd: failed to add new device\n");
+ return ret;
+ }
+ nbd = idr_find(&nbd_index_idr, new_index);
+ }
+ } else {
+ nbd = idr_find(&nbd_index_idr, index);
+ }
+ if (!nbd) {
+ printk(KERN_ERR "nbd: couldn't find device at index %d\n",
+ index);
+ mutex_unlock(&nbd_index_mutex);
+ return -EINVAL;
+ }
+ if (!refcount_inc_not_zero(&nbd->refs)) {
+ mutex_unlock(&nbd_index_mutex);
+ if (index == -1)
+ goto again;
+ printk(KERN_ERR "nbd: device at index %d is going down\n",
+ index);
+ return -EINVAL;
+ }
+ mutex_unlock(&nbd_index_mutex);
+
+ mutex_lock(&nbd->config_lock);
+ if (refcount_read(&nbd->config_refs)) {
+ mutex_unlock(&nbd->config_lock);
+ nbd_put(nbd);
+ if (index == -1)
+ goto again;
+ printk(KERN_ERR "nbd: nbd%d already in use\n", index);
+ return -EBUSY;
+ }
+ if (WARN_ON(nbd->config)) {
+ mutex_unlock(&nbd->config_lock);
+ nbd_put(nbd);
+ return -EINVAL;
+ }
+ config = nbd->config = nbd_alloc_config();
+ if (!nbd->config) {
+ mutex_unlock(&nbd->config_lock);
+ nbd_put(nbd);
+ printk(KERN_ERR "nbd: couldn't allocate config\n");
+ return -ENOMEM;
+ }
+ refcount_set(&nbd->config_refs, 1);
+ set_bit(NBD_BOUND, &config->runtime_flags);
+
+ if (info->attrs[NBD_ATTR_SIZE_BYTES]) {
+ u64 bytes = nla_get_u64(info->attrs[NBD_ATTR_SIZE_BYTES]);
+ nbd_size_set(nbd, config->blksize,
+ div64_u64(bytes, config->blksize));
+ }
+ if (info->attrs[NBD_ATTR_BLOCK_SIZE_BYTES]) {
+ u64 bsize =
+ nla_get_u64(info->attrs[NBD_ATTR_BLOCK_SIZE_BYTES]);
+ nbd_size_set(nbd, bsize, div64_u64(config->bytesize, bsize));
+ }
+ if (info->attrs[NBD_ATTR_TIMEOUT]) {
+ u64 timeout = nla_get_u64(info->attrs[NBD_ATTR_TIMEOUT]);
+ nbd->tag_set.timeout = timeout * HZ;
+ blk_queue_rq_timeout(nbd->disk->queue, timeout * HZ);
+ }
+ if (info->attrs[NBD_ATTR_DEAD_CONN_TIMEOUT]) {
+ config->dead_conn_timeout =
+ nla_get_u64(info->attrs[NBD_ATTR_DEAD_CONN_TIMEOUT]);
+ config->dead_conn_timeout *= HZ;
+ }
+ if (info->attrs[NBD_ATTR_SERVER_FLAGS])
+ config->flags =
+ nla_get_u64(info->attrs[NBD_ATTR_SERVER_FLAGS]);
+ if (info->attrs[NBD_ATTR_CLIENT_FLAGS]) {
+ u64 flags = nla_get_u64(info->attrs[NBD_ATTR_CLIENT_FLAGS]);
+ if (flags & NBD_CFLAG_DESTROY_ON_DISCONNECT) {
+ set_bit(NBD_DESTROY_ON_DISCONNECT,
+ &config->runtime_flags);
+ put_dev = true;
+ }
+ }
+
+ if (info->attrs[NBD_ATTR_SOCKETS]) {
+ struct nlattr *attr;
+ int rem, fd;
+
+ nla_for_each_nested(attr, info->attrs[NBD_ATTR_SOCKETS],
+ rem) {
+ struct nlattr *socks[NBD_SOCK_MAX+1];
+
+ if (nla_type(attr) != NBD_SOCK_ITEM) {
+ printk(KERN_ERR "nbd: socks must be embedded in a SOCK_ITEM attr\n");
+ ret = -EINVAL;
+ goto out;
+ }
+ ret = nla_parse_nested(socks, NBD_SOCK_MAX, attr,
- nbd_sock_policy);
++ nbd_sock_policy, info->extack);
+ if (ret != 0) {
+ printk(KERN_ERR "nbd: error processing sock list\n");
+ ret = -EINVAL;
+ goto out;
+ }
+ if (!socks[NBD_SOCK_FD])
+ continue;
+ fd = (int)nla_get_u32(socks[NBD_SOCK_FD]);
+ ret = nbd_add_socket(nbd, fd, true);
+ if (ret)
+ goto out;
+ }
+ }
+ ret = nbd_start_device(nbd);
+out:
+ mutex_unlock(&nbd->config_lock);
+ if (!ret) {
+ set_bit(NBD_HAS_CONFIG_REF, &config->runtime_flags);
+ refcount_inc(&nbd->config_refs);
+ nbd_connect_reply(info, nbd->index);
+ }
+ nbd_config_put(nbd);
+ if (put_dev)
+ nbd_put(nbd);
+ return ret;
+}
+
+static int nbd_genl_disconnect(struct sk_buff *skb, struct genl_info *info)
+{
+ struct nbd_device *nbd;
+ int index;
+
+ if (!netlink_capable(skb, CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (!info->attrs[NBD_ATTR_INDEX]) {
+ printk(KERN_ERR "nbd: must specify an index to disconnect\n");
+ return -EINVAL;
+ }
+ index = nla_get_u32(info->attrs[NBD_ATTR_INDEX]);
+ mutex_lock(&nbd_index_mutex);
+ nbd = idr_find(&nbd_index_idr, index);
+ if (!nbd) {
+ mutex_unlock(&nbd_index_mutex);
+ printk(KERN_ERR "nbd: couldn't find device at index %d\n",
+ index);
+ return -EINVAL;
+ }
+ if (!refcount_inc_not_zero(&nbd->refs)) {
+ mutex_unlock(&nbd_index_mutex);
+ printk(KERN_ERR "nbd: device at index %d is going down\n",
+ index);
+ return -EINVAL;
+ }
+ mutex_unlock(&nbd_index_mutex);
+ if (!refcount_inc_not_zero(&nbd->config_refs)) {
+ nbd_put(nbd);
+ return 0;
+ }
+ mutex_lock(&nbd->config_lock);
+ nbd_disconnect(nbd);
+ mutex_unlock(&nbd->config_lock);
+ if (test_and_clear_bit(NBD_HAS_CONFIG_REF,
+ &nbd->config->runtime_flags))
+ nbd_config_put(nbd);
+ nbd_config_put(nbd);
+ nbd_put(nbd);
+ return 0;
+}
+
+static int nbd_genl_reconfigure(struct sk_buff *skb, struct genl_info *info)
+{
+ struct nbd_device *nbd = NULL;
+ struct nbd_config *config;
+ int index;
+ int ret = -EINVAL;
+ bool put_dev = false;
+
+ if (!netlink_capable(skb, CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (!info->attrs[NBD_ATTR_INDEX]) {
+ printk(KERN_ERR "nbd: must specify a device to reconfigure\n");
+ return -EINVAL;
+ }
+ index = nla_get_u32(info->attrs[NBD_ATTR_INDEX]);
+ mutex_lock(&nbd_index_mutex);
+ nbd = idr_find(&nbd_index_idr, index);
+ if (!nbd) {
+ mutex_unlock(&nbd_index_mutex);
+ printk(KERN_ERR "nbd: couldn't find a device at index %d\n",
+ index);
+ return -EINVAL;
+ }
+ if (!refcount_inc_not_zero(&nbd->refs)) {
+ mutex_unlock(&nbd_index_mutex);
+ printk(KERN_ERR "nbd: device at index %d is going down\n",
+ index);
+ return -EINVAL;
+ }
+ mutex_unlock(&nbd_index_mutex);
+
+ if (!refcount_inc_not_zero(&nbd->config_refs)) {
+ dev_err(nbd_to_dev(nbd),
+ "not configured, cannot reconfigure\n");
+ nbd_put(nbd);
+ return -EINVAL;
+ }
+
+ mutex_lock(&nbd->config_lock);
+ config = nbd->config;
+ if (!test_bit(NBD_BOUND, &config->runtime_flags) ||
+ !nbd->task_recv) {
+ dev_err(nbd_to_dev(nbd),
+ "not configured, cannot reconfigure\n");
+ goto out;
+ }
+
+ if (info->attrs[NBD_ATTR_TIMEOUT]) {
+ u64 timeout = nla_get_u64(info->attrs[NBD_ATTR_TIMEOUT]);
+ nbd->tag_set.timeout = timeout * HZ;
+ blk_queue_rq_timeout(nbd->disk->queue, timeout * HZ);
+ }
+ if (info->attrs[NBD_ATTR_DEAD_CONN_TIMEOUT]) {
+ config->dead_conn_timeout =
+ nla_get_u64(info->attrs[NBD_ATTR_DEAD_CONN_TIMEOUT]);
+ config->dead_conn_timeout *= HZ;
+ }
+ if (info->attrs[NBD_ATTR_CLIENT_FLAGS]) {
+ u64 flags = nla_get_u64(info->attrs[NBD_ATTR_CLIENT_FLAGS]);
+ if (flags & NBD_CFLAG_DESTROY_ON_DISCONNECT) {
+ if (!test_and_set_bit(NBD_DESTROY_ON_DISCONNECT,
+ &config->runtime_flags))
+ put_dev = true;
+ } else {
+ if (test_and_clear_bit(NBD_DESTROY_ON_DISCONNECT,
+ &config->runtime_flags))
+ refcount_inc(&nbd->refs);
+ }
+ }
+
+ if (info->attrs[NBD_ATTR_SOCKETS]) {
+ struct nlattr *attr;
+ int rem, fd;
+
+ nla_for_each_nested(attr, info->attrs[NBD_ATTR_SOCKETS],
+ rem) {
+ struct nlattr *socks[NBD_SOCK_MAX+1];
+
+ if (nla_type(attr) != NBD_SOCK_ITEM) {
+ printk(KERN_ERR "nbd: socks must be embedded in a SOCK_ITEM attr\n");
+ ret = -EINVAL;
+ goto out;
+ }
+ ret = nla_parse_nested(socks, NBD_SOCK_MAX, attr,
++ nbd_sock_policy, info->extack);
+ if (ret != 0) {
+ printk(KERN_ERR "nbd: error processing sock list\n");
+ ret = -EINVAL;
+ goto out;
+ }
+ if (!socks[NBD_SOCK_FD])
+ continue;
+ fd = (int)nla_get_u32(socks[NBD_SOCK_FD]);
+ ret = nbd_reconnect_socket(nbd, fd);
+ if (ret) {
+ if (ret == -ENOSPC)
+ ret = 0;
+ goto out;
+ }
+ dev_info(nbd_to_dev(nbd), "reconnected socket\n");
+ }
+ }
+out:
+ mutex_unlock(&nbd->config_lock);
+ nbd_config_put(nbd);
+ nbd_put(nbd);
+ if (put_dev)
+ nbd_put(nbd);
+ return ret;
+}
+
+static const struct genl_ops nbd_connect_genl_ops[] = {
+ {
+ .cmd = NBD_CMD_CONNECT,
+ .policy = nbd_attr_policy,
+ .doit = nbd_genl_connect,
+ },
+ {
+ .cmd = NBD_CMD_DISCONNECT,
+ .policy = nbd_attr_policy,
+ .doit = nbd_genl_disconnect,
+ },
+ {
+ .cmd = NBD_CMD_RECONFIGURE,
+ .policy = nbd_attr_policy,
+ .doit = nbd_genl_reconfigure,
+ },
+ {
+ .cmd = NBD_CMD_STATUS,
+ .policy = nbd_attr_policy,
+ .doit = nbd_genl_status,
+ },
+};
+
+static const struct genl_multicast_group nbd_mcast_grps[] = {
+ { .name = NBD_GENL_MCAST_GROUP_NAME, },
+};
+
+static struct genl_family nbd_genl_family __ro_after_init = {
+ .hdrsize = 0,
+ .name = NBD_GENL_FAMILY_NAME,
+ .version = NBD_GENL_VERSION,
+ .module = THIS_MODULE,
+ .ops = nbd_connect_genl_ops,
+ .n_ops = ARRAY_SIZE(nbd_connect_genl_ops),
+ .maxattr = NBD_ATTR_MAX,
+ .mcgrps = nbd_mcast_grps,
+ .n_mcgrps = ARRAY_SIZE(nbd_mcast_grps),
+};
+
+static int populate_nbd_status(struct nbd_device *nbd, struct sk_buff *reply)
+{
+ struct nlattr *dev_opt;
+ u8 connected = 0;
+ int ret;
+
+ /* This is a little racey, but for status it's ok. The
+ * reason we don't take a ref here is because we can't
+ * take a ref in the index == -1 case as we would need
+ * to put under the nbd_index_mutex, which could
+ * deadlock if we are configured to remove ourselves
+ * once we're disconnected.
+ */
+ if (refcount_read(&nbd->config_refs))
+ connected = 1;
+ dev_opt = nla_nest_start(reply, NBD_DEVICE_ITEM);
+ if (!dev_opt)
+ return -EMSGSIZE;
+ ret = nla_put_u32(reply, NBD_DEVICE_INDEX, nbd->index);
+ if (ret)
+ return -EMSGSIZE;
+ ret = nla_put_u8(reply, NBD_DEVICE_CONNECTED,
+ connected);
+ if (ret)
+ return -EMSGSIZE;
+ nla_nest_end(reply, dev_opt);
+ return 0;
+}
+
+static int status_cb(int id, void *ptr, void *data)
+{
+ struct nbd_device *nbd = ptr;
+ return populate_nbd_status(nbd, (struct sk_buff *)data);
+}
+
+static int nbd_genl_status(struct sk_buff *skb, struct genl_info *info)
+{
+ struct nlattr *dev_list;
+ struct sk_buff *reply;
+ void *reply_head;
+ size_t msg_size;
+ int index = -1;
+ int ret = -ENOMEM;
+
+ if (info->attrs[NBD_ATTR_INDEX])
+ index = nla_get_u32(info->attrs[NBD_ATTR_INDEX]);
+
+ mutex_lock(&nbd_index_mutex);
+
+ msg_size = nla_total_size(nla_attr_size(sizeof(u32)) +
+ nla_attr_size(sizeof(u8)));
+ msg_size *= (index == -1) ? nbd_total_devices : 1;
+
+ reply = genlmsg_new(msg_size, GFP_KERNEL);
+ if (!reply)
+ goto out;
+ reply_head = genlmsg_put_reply(reply, info, &nbd_genl_family, 0,
+ NBD_CMD_STATUS);
+ if (!reply_head) {
+ nlmsg_free(reply);
+ goto out;
+ }
+
+ dev_list = nla_nest_start(reply, NBD_ATTR_DEVICE_LIST);
+ if (index == -1) {
+ ret = idr_for_each(&nbd_index_idr, &status_cb, reply);
+ if (ret) {
+ nlmsg_free(reply);
+ goto out;
+ }
+ } else {
+ struct nbd_device *nbd;
+ nbd = idr_find(&nbd_index_idr, index);
+ if (nbd) {
+ ret = populate_nbd_status(nbd, reply);
+ if (ret) {
+ nlmsg_free(reply);
+ goto out;
+ }
+ }
+ }
+ nla_nest_end(reply, dev_list);
+ genlmsg_end(reply, reply_head);
+ genlmsg_reply(reply, info);
+ ret = 0;
+out:
+ mutex_unlock(&nbd_index_mutex);
+ return ret;
+}
+
+static void nbd_connect_reply(struct genl_info *info, int index)
+{
+ struct sk_buff *skb;
+ void *msg_head;
+ int ret;
+
+ skb = genlmsg_new(nla_total_size(sizeof(u32)), GFP_KERNEL);
+ if (!skb)
+ return;
+ msg_head = genlmsg_put_reply(skb, info, &nbd_genl_family, 0,
+ NBD_CMD_CONNECT);
+ if (!msg_head) {
+ nlmsg_free(skb);
+ return;
+ }
+ ret = nla_put_u32(skb, NBD_ATTR_INDEX, index);
+ if (ret) {
+ nlmsg_free(skb);
+ return;
+ }
+ genlmsg_end(skb, msg_head);
+ genlmsg_reply(skb, info);
+}
+
+static void nbd_mcast_index(int index)
+{
+ struct sk_buff *skb;
+ void *msg_head;
+ int ret;
+
+ skb = genlmsg_new(nla_total_size(sizeof(u32)), GFP_KERNEL);
+ if (!skb)
+ return;
+ msg_head = genlmsg_put(skb, 0, 0, &nbd_genl_family, 0,
+ NBD_CMD_LINK_DEAD);
+ if (!msg_head) {
+ nlmsg_free(skb);
+ return;
+ }
+ ret = nla_put_u32(skb, NBD_ATTR_INDEX, index);
+ if (ret) {
+ nlmsg_free(skb);
+ return;
+ }
+ genlmsg_end(skb, msg_head);
+ genlmsg_multicast(&nbd_genl_family, skb, 0, 0, GFP_KERNEL);
+}
+
+static void nbd_dead_link_work(struct work_struct *work)
+{
+ struct link_dead_args *args = container_of(work, struct link_dead_args,
+ work);
+ nbd_mcast_index(args->index);
+ kfree(args);
+}
static int __init nbd_init(void)
{
projects / mirror_ubuntu-disco-kernel.git / commitdiff