From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from dggsgout12.his.huawei.com (dggsgout12.his.huawei.com [45.249.212.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3C32B3AC0E9 for ; Tue, 4 Aug 2026 08:48:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.56 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785833340; cv=none; b=nX1dklDWydONE8TcnzKQl51G2yCagQPZE5ApgXI+o9L1FzKmSkv9s4vuJJKyAwaW+Cpmy2quZwaJUKsFCu1akJbunAe/pxjTOI/kTR/9YH44O9AMURJ7Acz9T5TXALgZse/uuqsD0Z+Cu/LX6yV+PnxK6mwZbpRccfcHfA7b900= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785833340; c=relaxed/simple; bh=TKpkMdCYeifTinMW4pdygoIrg0D62NdMM+xpVWnJZco=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=qiewiJCGoKfVOiR0bXwFuvt67J5TnlGxIhcnxMLY//1mXWfSjrcs+DX5AjWp89k44gxR7lWgy2xQmLK9lorze7Hbca8wQ8jp/1c5vTjYQQznFYj9eN8bnDaD+m8Oe80tS/MhedZ1t2GGa2Ic4eD5Etn1oq1rAGfZcAEOQMpMNR8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.177]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTPS id 4hDnJW5tj0zKHMkj for ; Tue, 4 Aug 2026 16:48:43 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.252]) by mail.maildlp.com (Postfix) with ESMTP id 2F11F40590 for ; Tue, 4 Aug 2026 16:48:48 +0800 (CST) Received: from huaweicloud.com (unknown [10.50.85.155]) by APP3 (Coremail) with UTF8SMTPSA id _Ch0CgD35kVrp3Fq71VIBA--.52677S10; Tue, 04 Aug 2026 16:48:47 +0800 (CST) From: Yang Erkun To: josef@toxicpanda.com, axboe@kernel.dk, hch@lst.de, yukuai@kernel.org Cc: yi.zhang@huawei.com, chengzhihao1@huawei.com, echo.chenlin@huawei.com, leo.lilong@huaweicloud.com, wangkefeng.wang@huawei.com, huawei.libin@huawei.com, leijitang@huawei.com, linux-block@vger.kernel.org, nbd@other.debian.org Subject: [PATCH v6 6/8] nbd: factor out a nbd_genl_foreach_sock Date: Tue, 4 Aug 2026 16:39:20 +0800 Message-ID: <20260804083922.1927105-7-yangerkun@huawei.com> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260804083922.1927105-1-yangerkun@huawei.com> References: <20260804083922.1927105-1-yangerkun@huawei.com> Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CM-TRANSID:_Ch0CgD35kVrp3Fq71VIBA--.52677S10 X-Coremail-Antispam: 1UD129KBjvJXoW3Aw18Wr43tFWruF4kKw17ZFb_yoW7GrWUpF W0qFZ8Jr4DJr1xWFZ5Zw4kZa4SyF1xC3sIg3y7Kw1fZF17Cr43W3y8KryF9r45GryDWw13 Ar4Yga1Ikw4DWa7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUmCb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUAV Cq3wA2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0 rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVW8JVW5JwA2z4x0Y4vE2Ix0cI8IcVCY1x0267 AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_Cr1j6rxdM28EF7xvwVC2z280aVCY1x02 67AKxVW0oVCq3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I 80ewAv7VC0I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCj c4AY6r1j6r4UM4x0Y48IcxkI7VAKI48JM4IIrI8v6xkF7I0E8cxan2IY04v7MxkF7I0En4 kS14v26r1q6r43MxAIw28IcxkI7VAKI48JMxAIw28IcVAKzI0EY4vE52x082I5MxC20s02 6xCaFVCjc4AY6r1j6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_Jr I_JrWlx4CE17CEb7AF67AKxVWUtVW8ZwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v2 6r1I6r4UMIIF0xvE2Ix0cI8IcVCY1x0267AKxVWxJVW8Jr1lIxAIcVCF04k26cxKx2IYs7 xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Gr0_ Gr1UYxBIdaVFxhVjvjDU0xZFpf9x07UZyCLUUUUU= Sender: yangerkun@huaweicloud.com X-CM-SenderInfo: 51dqwvhunx0q5kxd4v5lfo033gof0z/ The NBD_ATTR_SOCKETS walk is duplicated in nbd_genl_connect (add sockets) and nbd_genl_reconfigure (reconnect). Factor out a single helper that walks the list and calls a callback per fd; with a NULL callback it is a pure counter, used by a later patch to learn nr_hw_queues before the device exists. Returns the number of fds walked (>= 0) or a negative errno; a callback >0 will stops early. Signed-off-by: Yang Erkun --- drivers/block/nbd.c | 131 ++++++++++++++++++++++---------------------- 1 file changed, 66 insertions(+), 65 deletions(-) diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index 66f1b3263b94..c080bb95653b 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -1399,11 +1399,12 @@ static int nbd_reconnect_socket(struct nbd_device *nbd, unsigned long arg) atomic_inc(&config->live_connections); wake_up(&config->conn_wait); + dev_info(nbd_to_dev(nbd), "reconnected socket\n"); return 0; } sockfd_put(sock); kfree(args); - return -ENOSPC; + return 1; } static void nbd_bdev_reset(struct nbd_device *nbd) @@ -2109,6 +2110,58 @@ static int nbd_genl_size_set(struct genl_info *info, struct nbd_device *nbd) return 0; } +/* + * Walk the NBD_ATTR_SOCKETS nested list can call @cb for each socket fd. + * + * Return the number of fds walked, or a negative errno. + */ +static int nbd_genl_foreach_sock(struct genl_info *info, + int (*cb)(struct nbd_device *nbd, int fd), + struct nbd_device *nbd) +{ + struct nlattr *attr; + int rem, count = 0; + + if (!info->attrs[NBD_ATTR_SOCKETS]) + return 0; + + nla_for_each_nested(attr, info->attrs[NBD_ATTR_SOCKETS], rem) { + struct nlattr *socks[NBD_SOCK_MAX + 1]; + int ret; + + if (nla_type(attr) != NBD_SOCK_ITEM) { + pr_err("socks must be embedded in a SOCK_ITEM attr\n"); + return -EINVAL; + } + + if (nla_parse_nested_deprecated(socks, NBD_SOCK_MAX, + attr, + nbd_sock_policy, + info->extack)) { + pr_err("error processing sock list\n"); + return -EINVAL; + } + + if (!socks[NBD_SOCK_FD]) + continue; + + count++; + if (cb) { + ret = cb(nbd, (int)nla_get_u32(socks[NBD_SOCK_FD])); + if (ret > 0) + return count; + if (ret < 0) + return ret; + } + } + return count; +} + +static int nbd_genl_connect_sock_cb(struct nbd_device *nbd, int fd) +{ + return nbd_add_socket(nbd, fd, true); +} + static int nbd_genl_connect(struct sk_buff *skb, struct genl_info *info) { struct nbd_device *nbd; @@ -2228,36 +2281,9 @@ static int nbd_genl_connect(struct sk_buff *skb, struct genl_info *info) } } - 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) { - pr_err("socks must be embedded in a SOCK_ITEM attr\n"); - ret = -EINVAL; - goto out; - } - ret = nla_parse_nested_deprecated(socks, NBD_SOCK_MAX, - attr, - nbd_sock_policy, - info->extack); - if (ret != 0) { - pr_err("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_genl_foreach_sock(info, nbd_genl_connect_sock_cb, nbd); + if (ret < 0) + goto out; if (info->attrs[NBD_ATTR_BACKEND_IDENTIFIER]) { nbd->backend = nla_strdup(info->attrs[NBD_ATTR_BACKEND_IDENTIFIER], @@ -2346,6 +2372,11 @@ static int nbd_genl_disconnect(struct sk_buff *skb, struct genl_info *info) return 0; } +static int nbd_genl_reconnect_sock_cb(struct nbd_device *nbd, int fd) +{ + return nbd_reconnect_socket(nbd, fd); +} + static int nbd_genl_reconfigure(struct sk_buff *skb, struct genl_info *info) { struct nbd_device *nbd = NULL; @@ -2442,40 +2473,10 @@ static int nbd_genl_reconfigure(struct sk_buff *skb, struct genl_info *info) } } - 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) { - pr_err("socks must be embedded in a SOCK_ITEM attr\n"); - ret = -EINVAL; - goto out; - } - ret = nla_parse_nested_deprecated(socks, NBD_SOCK_MAX, - attr, - nbd_sock_policy, - info->extack); - if (ret != 0) { - pr_err("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"); - } - } + ret = nbd_genl_foreach_sock(info, nbd_genl_reconnect_sock_cb, nbd); + /* foreach_sock returns a positive count on success; doit must return 0 */ + if (ret >= 0) + ret = 0; out: mutex_unlock(&nbd->config_lock); nbd_config_put(nbd); -- 2.52.0