From patchwork Tue Dec 20 03:21:43 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wen Gu X-Patchwork-Id: 13077487 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0B36EC4167B for ; Tue, 20 Dec 2022 03:22:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232912AbiLTDW1 (ORCPT ); Mon, 19 Dec 2022 22:22:27 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52928 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233079AbiLTDWF (ORCPT ); Mon, 19 Dec 2022 22:22:05 -0500 Received: from out30-8.freemail.mail.aliyun.com (out30-8.freemail.mail.aliyun.com [115.124.30.8]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1548813CFB; Mon, 19 Dec 2022 19:22:02 -0800 (PST) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R121e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018045192;MF=guwen@linux.alibaba.com;NM=1;PH=DS;RN=10;SR=0;TI=SMTPD_---0VXjTtLD_1671506518; Received: from localhost(mailfrom:guwen@linux.alibaba.com fp:SMTPD_---0VXjTtLD_1671506518) by smtp.aliyun-inc.com; Tue, 20 Dec 2022 11:22:00 +0800 From: Wen Gu To: kgraul@linux.ibm.com, wenjia@linux.ibm.com, jaka@linux.ibm.com, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com Cc: linux-s390@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [RFC PATCH net-next v2 3/5] net/smc: add dmb attach and detach interface Date: Tue, 20 Dec 2022 11:21:43 +0800 Message-Id: <1671506505-104676-4-git-send-email-guwen@linux.alibaba.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1671506505-104676-1-git-send-email-guwen@linux.alibaba.com> References: <1671506505-104676-1-git-send-email-guwen@linux.alibaba.com> Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org X-Patchwork-State: RFC This patch extends smcd_ops, adding two more semantic for SMC-D device: - attach_dmb: Attach an already registered dmb to a specific buf_desc, so that we can refer to the dmb through this buf_desc. - detach_dmb: Reverse operation of attach_dmb. detach the dmb from the buf_desc. This interface extension is to prepare for the reduction of data moving from sndbuf to RMB in SMC-D loopback device. Signed-off-by: Wen Gu --- include/net/smc.h | 2 ++ net/smc/smc_ism.c | 36 ++++++++++++++++++++++++++ net/smc/smc_ism.h | 2 ++ net/smc/smc_loopback.c | 69 ++++++++++++++++++++++++++++++++++++++++++++++++++ net/smc/smc_loopback.h | 4 +++ 5 files changed, 113 insertions(+) diff --git a/include/net/smc.h b/include/net/smc.h index 7699f97..60a96f7 100644 --- a/include/net/smc.h +++ b/include/net/smc.h @@ -63,6 +63,8 @@ struct smcd_ops { u32 vid); int (*register_dmb)(struct smcd_dev *dev, struct smcd_dmb *dmb); int (*unregister_dmb)(struct smcd_dev *dev, struct smcd_dmb *dmb); + int (*attach_dmb)(struct smcd_dev *dev, struct smcd_dmb *dmb); + int (*detach_dmb)(struct smcd_dev *dev, u64 token); int (*add_vlan_id)(struct smcd_dev *dev, u64 vlan_id); int (*del_vlan_id)(struct smcd_dev *dev, u64 vlan_id); int (*set_vlan_required)(struct smcd_dev *dev); diff --git a/net/smc/smc_ism.c b/net/smc/smc_ism.c index 1d10435..2049388 100644 --- a/net/smc/smc_ism.c +++ b/net/smc/smc_ism.c @@ -202,6 +202,42 @@ int smc_ism_register_dmb(struct smc_link_group *lgr, int dmb_len, return rc; } +int smc_ism_attach_dmb(struct smcd_dev *dev, u64 token, + struct smc_buf_desc *dmb_desc) +{ + struct smcd_dmb dmb; + int rc = 0; + + memset(&dmb, 0, sizeof(dmb)); + dmb.dmb_tok = token; + + /* only support loopback device now */ + if (!dev->is_loopback) + return -EINVAL; + if (!dev->ops->attach_dmb) + return -EINVAL; + + rc = dev->ops->attach_dmb(dev, &dmb); + if (!rc) { + dmb_desc->sba_idx = dmb.sba_idx; + dmb_desc->token = dmb.dmb_tok; + dmb_desc->cpu_addr = dmb.cpu_addr; + dmb_desc->dma_addr = dmb.dma_addr; + dmb_desc->len = dmb.dmb_len; + } + return rc; +} + +int smc_ism_detach_dmb(struct smcd_dev *dev, u64 token) +{ + if (!dev->is_loopback) + return -EINVAL; + if (!dev->ops->detach_dmb) + return -EINVAL; + + return dev->ops->detach_dmb(dev, token); +} + static int smc_nl_handle_smcd_dev(struct smcd_dev *smcd, struct sk_buff *skb, struct netlink_callback *cb) diff --git a/net/smc/smc_ism.h b/net/smc/smc_ism.h index d6b2db6..9022979 100644 --- a/net/smc/smc_ism.h +++ b/net/smc/smc_ism.h @@ -38,6 +38,8 @@ struct smc_ism_vlanid { /* VLAN id set on ISM device */ int smc_ism_register_dmb(struct smc_link_group *lgr, int buf_size, struct smc_buf_desc *dmb_desc); int smc_ism_unregister_dmb(struct smcd_dev *dev, struct smc_buf_desc *dmb_desc); +int smc_ism_attach_dmb(struct smcd_dev *dev, u64 token, struct smc_buf_desc *dmb_desc); +int smc_ism_detach_dmb(struct smcd_dev *dev, u64 token); int smc_ism_signal_shutdown(struct smc_link_group *lgr); void smc_ism_get_system_eid(u8 **eid); u16 smc_ism_get_chid(struct smcd_dev *dev); diff --git a/net/smc/smc_loopback.c b/net/smc/smc_loopback.c index 973382a..bc3ff82 100644 --- a/net/smc/smc_loopback.c +++ b/net/smc/smc_loopback.c @@ -68,6 +68,7 @@ static int lo_register_dmb(struct smcd_dev *smcd, struct smcd_dmb *dmb) goto err_node; } dmb_node->len = dmb->dmb_len; + refcount_set(&dmb_node->refcnt, 1); /* TODO: token is random but not exclusive ! * suppose to find token in dmb hask table, if has this token @@ -78,6 +79,7 @@ static int lo_register_dmb(struct smcd_dev *smcd, struct smcd_dmb *dmb) write_lock(&ldev->dmb_ht_lock); hash_add(ldev->dmb_ht, &dmb_node->list, dmb_node->token); write_unlock(&ldev->dmb_ht_lock); + atomic_inc(&ldev->dmb_cnt); dmb->sba_idx = dmb_node->sba_idx; dmb->dmb_tok = dmb_node->token; @@ -115,9 +117,69 @@ static int lo_unregister_dmb(struct smcd_dev *smcd, struct smcd_dmb *dmb) write_unlock(&ldev->dmb_ht_lock); clear_bit(dmb_node->sba_idx, ldev->sba_idx_mask); + + /* wait for dmb refcnt equal to 0 */ + if (!refcount_dec_and_test(&dmb_node->refcnt)) + wait_event(ldev->dmbs_release, !refcount_read(&dmb_node->refcnt)); kfree(dmb_node->cpu_addr); kfree(dmb_node); + if (atomic_dec_and_test(&ldev->dmb_cnt)) + wake_up(&ldev->ldev_release); + + return 0; +} + +static int lo_attach_dmb(struct smcd_dev *smcd, struct smcd_dmb *dmb) +{ + struct lo_dmb_node *dmb_node = NULL, *tmp_node; + struct lo_dev *ldev = smcd->priv; + + /* find dmb_node according to dmb->dmb_tok */ + read_lock(&ldev->dmb_ht_lock); + hash_for_each_possible(ldev->dmb_ht, tmp_node, list, dmb->dmb_tok) { + if (tmp_node->token == dmb->dmb_tok) { + dmb_node = tmp_node; + break; + } + } + if (!dmb_node) { + read_unlock(&ldev->dmb_ht_lock); + return -EINVAL; + } + read_unlock(&ldev->dmb_ht_lock); + refcount_inc(&dmb_node->refcnt); + + /* provide dmb information */ + dmb->sba_idx = dmb_node->sba_idx; + dmb->dmb_tok = dmb_node->token; + dmb->cpu_addr = dmb_node->cpu_addr; + dmb->dma_addr = dmb_node->dma_addr; + dmb->dmb_len = dmb_node->len; + return 0; +} + +static int lo_detach_dmb(struct smcd_dev *smcd, u64 token) +{ + struct lo_dmb_node *dmb_node = NULL, *tmp_node; + struct lo_dev *ldev = smcd->priv; + + /* find dmb_node according to dmb->dmb_tok */ + read_lock(&ldev->dmb_ht_lock); + hash_for_each_possible(ldev->dmb_ht, tmp_node, list, token) { + if (tmp_node->token == token) { + dmb_node = tmp_node; + break; + } + } + if (!dmb_node) { + read_unlock(&ldev->dmb_ht_lock); + return -EINVAL; + } + read_unlock(&ldev->dmb_ht_lock); + + if (refcount_dec_and_test(&dmb_node->refcnt)) + wake_up_all(&ldev->dmbs_release); return 0; } @@ -193,6 +255,8 @@ static u16 lo_get_chid(struct smcd_dev *smcd) .query_remote_gid = lo_query_rgid, .register_dmb = lo_register_dmb, .unregister_dmb = lo_unregister_dmb, + .attach_dmb = lo_attach_dmb, + .detach_dmb = lo_detach_dmb, .add_vlan_id = lo_add_vlan_id, .del_vlan_id = lo_del_vlan_id, .set_vlan_required = lo_set_vlan_required, @@ -218,6 +282,9 @@ static int lo_dev_init(struct lo_dev *ldev) ldev->lgid = smcd->local_gid; rwlock_init(&ldev->dmb_ht_lock); hash_init(ldev->dmb_ht); + atomic_set(&ldev->dmb_cnt, 0); + init_waitqueue_head(&ldev->dmbs_release); + init_waitqueue_head(&ldev->ldev_release); return smcd_register_dev(smcd); } @@ -255,6 +322,8 @@ static int lo_dev_probe(void) static void lo_dev_exit(struct lo_dev *ldev) { smcd_unregister_dev(ldev->smcd); + if (atomic_read(&ldev->dmb_cnt)) + wait_event(ldev->ldev_release, !atomic_read(&ldev->dmb_cnt)); } static void lo_dev_remove(void) diff --git a/net/smc/smc_loopback.h b/net/smc/smc_loopback.h index d7f7815..f4122be 100644 --- a/net/smc/smc_loopback.h +++ b/net/smc/smc_loopback.h @@ -32,6 +32,7 @@ struct lo_dmb_node { u32 sba_idx; void *cpu_addr; dma_addr_t dma_addr; + refcount_t refcnt; }; struct lo_dev { @@ -41,6 +42,9 @@ struct lo_dev { DECLARE_BITMAP(sba_idx_mask, LODEV_MAX_DMBS); rwlock_t dmb_ht_lock; DECLARE_HASHTABLE(dmb_ht, LODEV_MAX_DMBS_BUCKETS); + atomic_t dmb_cnt; + wait_queue_head_t dmbs_release; + wait_queue_head_t ldev_release; }; struct lo_systemeid {