// SPDX-License-Identifier: GPL-2.0 /* Shared Memory Communications Direct over ISM devices (SMC-D) * * Functions for ISM device. * * Copyright IBM Corp. 2018 */ #include #include #include #include #include #include "smc.h" #include "smc_core.h" #include "smc_ism.h" #include "smc_pnet.h" #include "smc_netlink.h" #include "linux/ism.h" struct smcd_dev_list smcd_dev_list = { .list = LIST_HEAD_INIT(smcd_dev_list.list), .mutex = __MUTEX_INITIALIZER(smcd_dev_list.mutex) }; static bool smc_ism_v2_capable; static u8 smc_ism_v2_system_eid[SMC_MAX_EID_LEN]; #if IS_ENABLED(CONFIG_ISM) static void smcd_register_dev(struct ism_dev *ism); static void smcd_unregister_dev(struct ism_dev *ism); static void smcd_handle_event(struct ism_dev *ism, struct ism_event *event); static void smcd_handle_irq(struct ism_dev *ism, unsigned int dmbno, u16 dmbemask); static struct ism_client smc_ism_client = { .name = "SMC-D", .add = smcd_register_dev, .remove = smcd_unregister_dev, .handle_event = smcd_handle_event, .handle_irq = smcd_handle_irq, }; #endif /* Test if an ISM communication is possible - same CPC */ int smc_ism_cantalk(struct smcd_gid *peer_gid, unsigned short vlan_id, struct smcd_dev *smcd) { return smcd->ops->query_remote_gid(smcd, peer_gid, vlan_id ? 1 : 0, vlan_id); } void smc_ism_get_system_eid(u8 **eid) { if (!smc_ism_v2_capable) *eid = NULL; else *eid = smc_ism_v2_system_eid; } u16 smc_ism_get_chid(struct smcd_dev *smcd) { return smcd->ops->get_chid(smcd); } /* HW supports ISM V2 and thus System EID is defined */ bool smc_ism_is_v2_capable(void) { return smc_ism_v2_capable; } /* Set a connection using this DMBE. */ void smc_ism_set_conn(struct smc_connection *conn) { unsigned long flags; spin_lock_irqsave(&conn->lgr->smcd->lock, flags); conn->lgr->smcd->conn[conn->rmb_desc->sba_idx] = conn; spin_unlock_irqrestore(&conn->lgr->smcd->lock, flags); } /* Unset a connection using this DMBE. */ void smc_ism_unset_conn(struct smc_connection *conn) { unsigned long flags; if (!conn->rmb_desc) return; spin_lock_irqsave(&conn->lgr->smcd->lock, flags); conn->lgr->smcd->conn[conn->rmb_desc->sba_idx] = NULL; spin_unlock_irqrestore(&conn->lgr->smcd->lock, flags); } /* Register a VLAN identifier with the ISM device. Use a reference count * and add a VLAN identifier only when the first DMB using this VLAN is * registered. */ int smc_ism_get_vlan(struct smcd_dev *smcd, unsigned short vlanid) { struct smc_ism_vlanid *new_vlan, *vlan; unsigned long flags; int rc = 0; if (!vlanid) /* No valid vlan id */ return -EINVAL; if (!smcd->ops->add_vlan_id) return -EOPNOTSUPP; /* create new vlan entry, in case we need it */ new_vlan = kzalloc(sizeof(*new_vlan), GFP_KERNEL); if (!new_vlan) return -ENOMEM; new_vlan->vlanid = vlanid; refcount_set(&new_vlan->refcnt, 1); /* if there is an existing entry, increase count and return */ spin_lock_irqsave(&smcd->lock, flags); list_for_each_entry(vlan, &smcd->vlan, list) { if (vlan->vlanid == vlanid) { refcount_inc(&vlan->refcnt); kfree(new_vlan); goto out; } } /* no existing entry found. * add new entry to device; might fail, e.g., if HW limit reached */ if (smcd->ops->add_vlan_id(smcd, vlanid)) { kfree(new_vlan); rc = -EIO; goto out; } list_add_tail(&new_vlan->list, &smcd->vlan); out: spin_unlock_irqrestore(&smcd->lock, flags); return rc; } /* Unregister a VLAN identifier with the ISM device. Use a reference count * and remove a VLAN identifier only when the last DMB using this VLAN is * unregistered. */ int smc_ism_put_vlan(struct smcd_dev *smcd, unsigned short vlanid) { struct smc_ism_vlanid *vlan; unsigned long flags; bool found = false; int rc = 0; if (!vlanid) /* No valid vlan id */ return -EINVAL; if (!smcd->ops->del_vlan_id) return -EOPNOTSUPP; spin_lock_irqsave(&smcd->lock, flags); list_for_each_entry(vlan, &smcd->vlan, list) { if (vlan->vlanid == vlanid) { if (!refcount_dec_and_test(&vlan->refcnt)) goto out; found = true; break; } } if (!found) { rc = -ENOENT; goto out; /* VLAN id not in table */ } /* Found and the last reference just gone */ if (smcd->ops->del_vlan_id(smcd, vlanid)) rc = -EIO; list_del(&vlan->list); kfree(vlan); out: spin_unlock_irqrestore(&smcd->lock, flags); return rc; } int smc_ism_unregister_dmb(struct smcd_dev *smcd, struct smc_buf_desc *dmb_desc) { struct smcd_dmb dmb; int rc = 0; if (!dmb_desc->dma_addr) return rc; memset(&dmb, 0, sizeof(dmb)); dmb.dmb_tok = dmb_desc->token; dmb.sba_idx = dmb_desc->sba_idx; dmb.cpu_addr = dmb_desc->cpu_addr; dmb.dma_addr = dmb_desc->dma_addr; dmb.dmb_len = dmb_desc->len; rc = smcd->ops->unregister_dmb(smcd, &dmb); if (!rc || rc == ISM_ERROR) { dmb_desc->cpu_addr = NULL; dmb_desc->dma_addr = 0; } return rc; } int smc_ism_register_dmb(struct smc_link_group *lgr, int dmb_len, struct smc_buf_desc *dmb_desc) { #if IS_ENABLED(CONFIG_ISM) struct smcd_dmb dmb; int rc; memset(&dmb, 0, sizeof(dmb)); dmb.dmb_len = dmb_len; dmb.sba_idx = dmb_desc->sba_idx; dmb.vlan_id = lgr->vlan_id; dmb.rgid = lgr->peer_gid.gid; rc = lgr->smcd->ops->register_dmb(lgr->smcd, &dmb, &smc_ism_client); 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; #else return 0; #endif } bool smc_ism_support_dmb_nocopy(struct smcd_dev *smcd) { /* for now only loopback-ism supports * merging sndbuf with peer DMB to avoid * data copies between them. */ return (smcd->ops->support_dmb_nocopy && smcd->ops->support_dmb_nocopy(smcd)); } int smc_ism_attach_dmb(struct smcd_dev *dev, u64 token, struct smc_buf_desc *dmb_desc) { struct smcd_dmb dmb; int rc = 0; if (!dev->ops->attach_dmb) return -EINVAL; memset(&dmb, 0, sizeof(dmb)); dmb.dmb_tok = token; 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->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) { char smc_pnet[SMC_MAX_PNETID_LEN + 1]; struct smc_pci_dev smc_pci_dev; struct nlattr *port_attrs; struct nlattr *attrs; struct ism_dev *ism; int use_cnt = 0; void *nlh; ism = smcd->priv; nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, &smc_gen_nl_family, NLM_F_MULTI, SMC_NETLINK_GET_DEV_SMCD); if (!nlh) goto errmsg; attrs = nla_nest_start(skb, SMC_GEN_DEV_SMCD); if (!attrs) goto errout; use_cnt = atomic_read(&smcd->lgr_cnt); if (nla_put_u32(skb, SMC_NLA_DEV_USE_CNT, use_cnt)) goto errattr; if (nla_put_u8(skb, SMC_NLA_DEV_IS_CRIT, use_cnt > 0)) goto errattr; memset(&smc_pci_dev, 0, sizeof(smc_pci_dev)); smc_set_pci_values(to_pci_dev(ism->dev.parent), &smc_pci_dev); if (nla_put_u32(skb, SMC_NLA_DEV_PCI_FID, smc_pci_dev.pci_fid)) goto errattr; if (nla_put_u16(skb, SMC_NLA_DEV_PCI_CHID, smc_pci_dev.pci_pchid)) goto errattr; if (nla_put_u16(skb, SMC_NLA_DEV_PCI_VENDOR, smc_pci_dev.pci_vendor)) goto errattr; if (nla_put_u16(skb, SMC_NLA_DEV_PCI_DEVICE, smc_pci_dev.pci_device)) goto errattr; if (nla_put_string(skb, SMC_NLA_DEV_PCI_ID, smc_pci_dev.pci_id)) goto errattr; port_attrs = nla_nest_start(skb, SMC_NLA_DEV_PORT); if (!port_attrs) goto errattr; if (nla_put_u8(skb, SMC_NLA_DEV_PORT_PNET_USR, smcd->pnetid_by_user)) goto errportattr; memcpy(smc_pnet, smcd->pnetid, SMC_MAX_PNETID_LEN); smc_pnet[SMC_MAX_PNETID_LEN] = 0; if (nla_put_string(skb, SMC_NLA_DEV_PORT_PNETID, smc_pnet)) goto errportattr; nla_nest_end(skb, port_attrs); nla_nest_end(skb, attrs); genlmsg_end(skb, nlh); return 0; errportattr: nla_nest_cancel(skb, port_attrs); errattr: nla_nest_cancel(skb, attrs); errout: nlmsg_cancel(skb, nlh); errmsg: return -EMSGSIZE; } static void smc_nl_prep_smcd_dev(struct smcd_dev_list *dev_list, struct sk_buff *skb, struct netlink_callback *cb) { struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb); int snum = cb_ctx->pos[0]; struct smcd_dev *smcd; int num = 0; mutex_lock(&dev_list->mutex); list_for_each_entry(smcd, &dev_list->list, list) { if (num < snum) goto next; if (smc_nl_handle_smcd_dev(smcd, skb, cb)) goto errout; next: num++; } errout: mutex_unlock(&dev_list->mutex); cb_ctx->pos[0] = num; } int smcd_nl_get_device(struct sk_buff *skb, struct netlink_callback *cb) { smc_nl_prep_smcd_dev(&smcd_dev_list, skb, cb); return skb->len; } #if IS_ENABLED(CONFIG_ISM) struct smc_ism_event_work { struct work_struct work; struct smcd_dev *smcd; struct ism_event event; }; #define ISM_EVENT_REQUEST 0x0001 #define ISM_EVENT_RESPONSE 0x0002 #define ISM_EVENT_REQUEST_IR 0x00000001 #define ISM_EVENT_CODE_SHUTDOWN 0x80 #define ISM_EVENT_CODE_TESTLINK 0x83 union smcd_sw_event_info { u64 info; struct { u8 uid[SMC_LGR_ID_SIZE]; unsigned short vlan_id; u16 code; }; }; static void smcd_handle_sw_event(struct smc_ism_event_work *wrk) { struct smcd_gid peer_gid = { .gid = wrk->event.tok, .gid_ext = 0 }; union smcd_sw_event_info ev_info; ev_info.info = wrk->event.info; switch (wrk->event.code) { case ISM_EVENT_CODE_SHUTDOWN: /* Peer shut down DMBs */ smc_smcd_terminate(wrk->smcd, &peer_gid, ev_info.vlan_id); break; case ISM_EVENT_CODE_TESTLINK: /* Activity timer */ if (ev_info.code == ISM_EVENT_REQUEST && wrk->smcd->ops->signal_event) { ev_info.code = ISM_EVENT_RESPONSE; wrk->smcd->ops->signal_event(wrk->smcd, &peer_gid, ISM_EVENT_REQUEST_IR, ISM_EVENT_CODE_TESTLINK, ev_info.info); } break; } } /* worker for SMC-D events */ static void smc_ism_event_work(struct work_struct *work) { struct smc_ism_event_work *wrk = container_of(work, struct smc_ism_event_work, work); struct smcd_gid smcd_gid = { .gid = wrk->event.tok, .gid_ext = 0 }; switch (wrk->event.type) { case ISM_EVENT_GID: /* GID event, token is peer GID */ smc_smcd_terminate(wrk->smcd, &smcd_gid, VLAN_VID_MASK); break; case ISM_EVENT_DMB: break; case ISM_EVENT_SWR: /* Software defined event */ smcd_handle_sw_event(wrk); break; } kfree(wrk); } static struct smcd_dev *smcd_alloc_dev(struct device *parent, const char *name, const struct smcd_ops *ops, int max_dmbs) { struct smcd_dev *smcd; smcd = devm_kzalloc(parent, sizeof(*smcd), GFP_KERNEL); if (!smcd) return NULL; smcd->conn = devm_kcalloc(parent, max_dmbs, sizeof(struct smc_connection *), GFP_KERNEL); if (!smcd->conn) return NULL; smcd->event_wq = alloc_ordered_workqueue("ism_evt_wq-%s)", WQ_MEM_RECLAIM, name); if (!smcd->event_wq) return NULL; smcd->ops = ops; spin_lock_init(&smcd->lock); spin_lock_init(&smcd->lgr_lock); INIT_LIST_HEAD(&smcd->vlan); INIT_LIST_HEAD(&smcd->lgr_list); init_waitqueue_head(&smcd->lgrs_deleted); return smcd; } static void smcd_register_dev(struct ism_dev *ism) { const struct smcd_ops *ops = ism_get_smcd_ops(); struct smcd_dev *smcd; if (!ops) return; smcd = smcd_alloc_dev(&ism->pdev->dev, dev_name(&ism->pdev->dev), ops, ISM_NR_DMBS); if (!smcd) return; smcd->priv = ism; ism_set_priv(ism, &smc_ism_client, smcd); if (smc_pnetid_by_dev_port(&ism->pdev->dev, 0, smcd->pnetid)) smc_pnetid_by_table_smcd(smcd); mutex_lock(&smcd_dev_list.mutex); if (list_empty(&smcd_dev_list.list)) { u8 *system_eid = NULL; system_eid = smcd->ops->get_system_eid(); if (smcd->ops->supports_v2()) { smc_ism_v2_capable = true; memcpy(smc_ism_v2_system_eid, system_eid, SMC_MAX_EID_LEN); } } /* sort list: devices without pnetid before devices with pnetid */ if (smcd->pnetid[0]) list_add_tail(&smcd->list, &smcd_dev_list.list); else list_add(&smcd->list, &smcd_dev_list.list); mutex_unlock(&smcd_dev_list.mutex); pr_warn_ratelimited("smc: adding smcd device %s with pnetid %.16s%s\n", dev_name(&ism->dev), smcd->pnetid, smcd->pnetid_by_user ? " (user defined)" : ""); return; } static void smcd_unregister_dev(struct ism_dev *ism) { struct smcd_dev *smcd = ism_get_priv(ism, &smc_ism_client); pr_warn_ratelimited("smc: removing smcd device %s\n", dev_name(&ism->dev)); smcd->going_away = 1; smc_smcd_terminate_all(smcd); mutex_lock(&smcd_dev_list.mutex); list_del_init(&smcd->list); mutex_unlock(&smcd_dev_list.mutex); destroy_workqueue(smcd->event_wq); } /* SMCD Device event handler. Called from ISM device interrupt handler. * Parameters are ism device pointer, * - event->type (0 --> DMB, 1 --> GID), * - event->code (event code), * - event->tok (either DMB token when event type 0, or GID when event type 1) * - event->time (time of day) * - event->info (debug info). * * Context: * - Function called in IRQ context from ISM device driver event handler. */ static void smcd_handle_event(struct ism_dev *ism, struct ism_event *event) { struct smcd_dev *smcd = ism_get_priv(ism, &smc_ism_client); struct smc_ism_event_work *wrk; if (smcd->going_away) return; /* copy event to event work queue, and let it be handled there */ wrk = kmalloc(sizeof(*wrk), GFP_ATOMIC); if (!wrk) return; INIT_WORK(&wrk->work, smc_ism_event_work); wrk->smcd = smcd; wrk->event = *event; queue_work(smcd->event_wq, &wrk->work); } /* SMCD Device interrupt handler. Called from ISM device interrupt handler. * Parameters are the ism device pointer, DMB number, and the DMBE bitmask. * Find the connection and schedule the tasklet for this connection. * * Context: * - Function called in IRQ context from ISM device driver IRQ handler. */ static void smcd_handle_irq(struct ism_dev *ism, unsigned int dmbno, u16 dmbemask) { struct smcd_dev *smcd = ism_get_priv(ism, &smc_ism_client); struct smc_connection *conn = NULL; unsigned long flags; spin_lock_irqsave(&smcd->lock, flags); conn = smcd->conn[dmbno]; if (conn && !conn->killed) tasklet_schedule(&conn->rx_tsklet); spin_unlock_irqrestore(&smcd->lock, flags); } #endif int smc_ism_signal_shutdown(struct smc_link_group *lgr) { int rc = 0; #if IS_ENABLED(CONFIG_ISM) union smcd_sw_event_info ev_info; if (lgr->peer_shutdown) return 0; if (!lgr->smcd->ops->signal_event) return 0; memcpy(ev_info.uid, lgr->id, SMC_LGR_ID_SIZE); ev_info.vlan_id = lgr->vlan_id; ev_info.code = ISM_EVENT_REQUEST; rc = lgr->smcd->ops->signal_event(lgr->smcd, &lgr->peer_gid, ISM_EVENT_REQUEST_IR, ISM_EVENT_CODE_SHUTDOWN, ev_info.info); #endif return rc; } int smc_ism_init(void) { int rc = 0; #if IS_ENABLED(CONFIG_ISM) smc_ism_v2_capable = false; memset(smc_ism_v2_system_eid, 0, SMC_MAX_EID_LEN); rc = ism_register_client(&smc_ism_client); #endif return rc; } void smc_ism_exit(void) { #if IS_ENABLED(CONFIG_ISM) ism_unregister_client(&smc_ism_client); #endif }