/* * Copyright (c) 2004, 2005 Intel Corporation. All rights reserved. * Copyright (c) 2004 Topspin Corporation. All rights reserved. * Copyright (c) 2004, 2005 Voltaire Corporation. All rights reserved. * Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved. * Copyright (c) 2005 Open Grid Computing, Inc. All rights reserved. * Copyright (c) 2005 Network Appliance, Inc. All rights reserved. * * This software is available to you under a choice of one of two * licenses. You may choose to be licensed under the terms of the GNU * General Public License (GPL) Version 2, available from the file * COPYING in the main directory of this source tree, or the * OpenIB.org BSD license below: * * Redistribution and use in source and binary forms, with or * without modification, are permitted provided that the following * conditions are met: * * - Redistributions of source code must retain the above * copyright notice, this list of conditions and the following * disclaimer. * * - Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials * provided with the distribution. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. * */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "iwcm.h" MODULE_AUTHOR("Tom Tucker"); MODULE_DESCRIPTION("iWARP CM"); MODULE_LICENSE("Dual BSD/GPL"); static const char * const iwcm_rej_reason_strs[] = { [ECONNRESET] = "reset by remote host", [ECONNREFUSED] = "refused by remote application", [ETIMEDOUT] = "setup timeout", }; const char *__attribute_const__ iwcm_reject_msg(int reason) { size_t index; /* iWARP uses negative errnos */ index = -reason; if (index < ARRAY_SIZE(iwcm_rej_reason_strs) && iwcm_rej_reason_strs[index]) return iwcm_rej_reason_strs[index]; else return "unrecognized reason"; } EXPORT_SYMBOL(iwcm_reject_msg); static struct rdma_nl_cbs iwcm_nl_cb_table[RDMA_NL_IWPM_NUM_OPS] = { [RDMA_NL_IWPM_REG_PID] = {.dump = iwpm_register_pid_cb}, [RDMA_NL_IWPM_ADD_MAPPING] = {.dump = iwpm_add_mapping_cb}, [RDMA_NL_IWPM_QUERY_MAPPING] = {.dump = iwpm_add_and_query_mapping_cb}, [RDMA_NL_IWPM_REMOTE_INFO] = {.dump = iwpm_remote_info_cb}, [RDMA_NL_IWPM_HANDLE_ERR] = {.dump = iwpm_mapping_error_cb}, [RDMA_NL_IWPM_MAPINFO] = {.dump = iwpm_mapping_info_cb}, [RDMA_NL_IWPM_MAPINFO_NUM] = {.dump = iwpm_ack_mapping_info_cb}, [RDMA_NL_IWPM_HELLO] = {.dump = iwpm_hello_cb} }; static struct workqueue_struct *iwcm_wq; struct iwcm_work { struct work_struct work; struct iwcm_id_private *cm_id; struct list_head list; struct iw_cm_event event; struct list_head free_list; }; static unsigned int default_backlog = 256; static struct ctl_table_header *iwcm_ctl_table_hdr; static struct ctl_table iwcm_ctl_table[] = { { .procname = "default_backlog", .data = &default_backlog, .maxlen = sizeof(default_backlog), .mode = 0644, .proc_handler = proc_dointvec, }, { } }; /* * The following services provide a mechanism for pre-allocating iwcm_work * elements. The design pre-allocates them based on the cm_id type: * LISTENING IDS: Get enough elements preallocated to handle the * listen backlog. * ACTIVE IDS: 4: CONNECT_REPLY, ESTABLISHED, DISCONNECT, CLOSE * PASSIVE IDS: 3: ESTABLISHED, DISCONNECT, CLOSE * * Allocating them in connect and listen avoids having to deal * with allocation failures on the event upcall from the provider (which * is called in the interrupt context). * * One exception is when creating the cm_id for incoming connection requests. * There are two cases: * 1) in the event upcall, cm_event_handler(), for a listening cm_id. If * the backlog is exceeded, then no more connection request events will * be processed. cm_event_handler() returns -ENOMEM in this case. Its up * to the provider to reject the connection request. * 2) in the connection request workqueue handler, cm_conn_req_handler(). * If work elements cannot be allocated for the new connect request cm_id, * then IWCM will call the provider reject method. This is ok since * cm_conn_req_handler() runs in the workqueue thread context. */ static struct iwcm_work *get_work(struct iwcm_id_private *cm_id_priv) { struct iwcm_work *work; if (list_empty(&cm_id_priv->work_free_list)) return NULL; work = list_entry(cm_id_priv->work_free_list.next, struct iwcm_work, free_list); list_del_init(&work->free_list); return work; } static void put_work(struct iwcm_work *work) { list_add(&work->free_list, &work->cm_id->work_free_list); } static void dealloc_work_entries(struct iwcm_id_private *cm_id_priv) { struct list_head *e, *tmp; list_for_each_safe(e, tmp, &cm_id_priv->work_free_list) { list_del(e); kfree(list_entry(e, struct iwcm_work, free_list)); } } static int alloc_work_entries(struct iwcm_id_private *cm_id_priv, int count) { struct iwcm_work *work; BUG_ON(!list_empty(&cm_id_priv->work_free_list)); while (count--) { work = kmalloc(sizeof(struct iwcm_work), GFP_KERNEL); if (!work) { dealloc_work_entries(cm_id_priv); return -ENOMEM; } work->cm_id = cm_id_priv; INIT_LIST_HEAD(&work->list); put_work(work); } return 0; } /* * Save private data from incoming connection requests to * iw_cm_event, so the low level driver doesn't have to. Adjust * the event ptr to point to the local copy. */ static int copy_private_data(struct iw_cm_event *event) { void *p; p = kmemdup(event->private_data, event->private_data_len, GFP_ATOMIC); if (!p) return -ENOMEM; event->private_data = p; return 0; } static void free_cm_id(struct iwcm_id_private *cm_id_priv) { dealloc_work_entries(cm_id_priv); kfree(cm_id_priv); } /* * Release a reference on cm_id. If the last reference is being * released, free the cm_id and return 1. */ static int iwcm_deref_id(struct iwcm_id_private *cm_id_priv) { if (refcount_dec_and_test(&cm_id_priv->refcount)) { BUG_ON(!list_empty(&cm_id_priv->work_list)); free_cm_id(cm_id_priv); return 1; } return 0; } static void add_ref(struct iw_cm_id *cm_id) { struct iwcm_id_private *cm_id_priv; cm_id_priv = container_of(cm_id, struct iwcm_id_private, id); refcount_inc(&cm_id_priv->refcount); } static void rem_ref(struct iw_cm_id *cm_id) { struct iwcm_id_private *cm_id_priv; cm_id_priv = container_of(cm_id, struct iwcm_id_private, id); (void)iwcm_deref_id(cm_id_priv); } static int cm_event_handler(struct iw_cm_id *cm_id, struct iw_cm_event *event); struct iw_cm_id *iw_create_cm_id(struct ib_device *device, iw_cm_handler cm_handler, void *context) { struct iwcm_id_private *cm_id_priv; cm_id_priv = kzalloc(sizeof(*cm_id_priv), GFP_KERNEL); if (!cm_id_priv) return ERR_PTR(-ENOMEM); cm_id_priv->state = IW_CM_STATE_IDLE; cm_id_priv->id.device = device; cm_id_priv->id.cm_handler = cm_handler; cm_id_priv->id.context = context; cm_id_priv->id.event_handler = cm_event_handler; cm_id_priv->id.add_ref = add_ref; cm_id_priv->id.rem_ref = rem_ref; spin_lock_init(&cm_id_priv->lock); refcount_set(&cm_id_priv->refcount, 1); init_waitqueue_head(&cm_id_priv->connect_wait); init_completion(&cm_id_priv->destroy_comp); INIT_LIST_HEAD(&cm_id_priv->work_list); INIT_LIST_HEAD(&cm_id_priv->work_free_list); return &cm_id_priv->id; } EXPORT_SYMBOL(iw_create_cm_id); static int iwcm_modify_qp_err(struct ib_qp *qp) { struct ib_qp_attr qp_attr; if (!qp) return -EINVAL; qp_attr.qp_state = IB_QPS_ERR; return ib_modify_qp(qp, &qp_attr, IB_QP_STATE); } /* * This is really the RDMAC CLOSING state. It is most similar to the * IB SQD QP state. */ static int iwcm_modify_qp_sqd(struct ib_qp *qp) { struct ib_qp_attr qp_attr; BUG_ON(qp == NULL); qp_attr.qp_state = IB_QPS_SQD; return ib_modify_qp(qp, &qp_attr, IB_QP_STATE); } /* * CM_ID <-- CLOSING * * Block if a passive or active connection is currently being processed. Then * process the event as follows: * - If we are ESTABLISHED, move to CLOSING and modify the QP state * based on the abrupt flag * - If the connection is already in the CLOSING or IDLE state, the peer is * disconnecting concurrently with us and we've already seen the * DISCONNECT event -- ignore the request and return 0 * - Disconnect on a listening endpoint returns -EINVAL */ int iw_cm_disconnect(struct iw_cm_id *cm_id, int abrupt) { struct iwcm_id_private *cm_id_priv; unsigned long flags; int ret = 0; struct ib_qp *qp = NULL; cm_id_priv = container_of(cm_id, struct iwcm_id_private, id); /* Wait if we're currently in a connect or accept downcall */ wait_event(cm_id_priv->connect_wait, !test_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags)); spin_lock_irqsave(&cm_id_priv->lock, flags); switch (cm_id_priv->state) { case IW_CM_STATE_ESTABLISHED: cm_id_priv->state = IW_CM_STATE_CLOSING; /* QP could be for user-mode client */ if (cm_id_priv->qp) qp = cm_id_priv->qp; else ret = -EINVAL; break; case IW_CM_STATE_LISTEN: ret = -EINVAL; break; case IW_CM_STATE_CLOSING: /* remote peer closed first */ case IW_CM_STATE_IDLE: /* accept or connect returned !0 */ break; case IW_CM_STATE_CONN_RECV: /* * App called disconnect before/without calling accept after * connect_request event delivered. */ break; case IW_CM_STATE_CONN_SENT: /* Can only get here if wait above fails */ default: BUG(); } spin_unlock_irqrestore(&cm_id_priv->lock, flags); if (qp) { if (abrupt) ret = iwcm_modify_qp_err(qp); else ret = iwcm_modify_qp_sqd(qp); /* * If both sides are disconnecting the QP could * already be in ERR or SQD states */ ret = 0; } return ret; } EXPORT_SYMBOL(iw_cm_disconnect); /* * CM_ID <-- DESTROYING * * Clean up all resources associated with the connection and release * the initial reference taken by iw_create_cm_id. * * Returns true if and only if the last cm_id_priv reference has been dropped. */ static bool destroy_cm_id(struct iw_cm_id *cm_id) { struct iwcm_id_private *cm_id_priv; struct ib_qp *qp; unsigned long flags; cm_id_priv = container_of(cm_id, struct iwcm_id_private, id); /* * Wait if we're currently in a connect or accept downcall. A * listening endpoint should never block here. */ wait_event(cm_id_priv->connect_wait, !test_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags)); /* * Since we're deleting the cm_id, drop any events that * might arrive before the last dereference. */ set_bit(IWCM_F_DROP_EVENTS, &cm_id_priv->flags); spin_lock_irqsave(&cm_id_priv->lock, flags); qp = cm_id_priv->qp; cm_id_priv->qp = NULL; switch (cm_id_priv->state) { case IW_CM_STATE_LISTEN: cm_id_priv->state = IW_CM_STATE_DESTROYING; spin_unlock_irqrestore(&cm_id_priv->lock, flags); /* destroy the listening endpoint */ cm_id->device->ops.iw_destroy_listen(cm_id); spin_lock_irqsave(&cm_id_priv->lock, flags); break; case IW_CM_STATE_ESTABLISHED: cm_id_priv->state = IW_CM_STATE_DESTROYING; spin_unlock_irqrestore(&cm_id_priv->lock, flags); /* Abrupt close of the connection */ (void)iwcm_modify_qp_err(qp); spin_lock_irqsave(&cm_id_priv->lock, flags); break; case IW_CM_STATE_IDLE: case IW_CM_STATE_CLOSING: cm_id_priv->state = IW_CM_STATE_DESTROYING; break; case IW_CM_STATE_CONN_RECV: /* * App called destroy before/without calling accept after * receiving connection request event notification or * returned non zero from the event callback function. * In either case, must tell the provider to reject. */ cm_id_priv->state = IW_CM_STATE_DESTROYING; spin_unlock_irqrestore(&cm_id_priv->lock, flags); cm_id->device->ops.iw_reject(cm_id, NULL, 0); spin_lock_irqsave(&cm_id_priv->lock, flags); break; case IW_CM_STATE_CONN_SENT: case IW_CM_STATE_DESTROYING: default: BUG(); break; } spin_unlock_irqrestore(&cm_id_priv->lock, flags); if (qp) cm_id_priv->id.device->ops.iw_rem_ref(qp); if (cm_id->mapped) { iwpm_remove_mapinfo(&cm_id->local_addr, &cm_id->m_local_addr); iwpm_remove_mapping(&cm_id->local_addr, RDMA_NL_IWCM); } return iwcm_deref_id(cm_id_priv); } /* * This function is only called by the application thread and cannot * be called by the event thread. The function will wait for all * references to be released on the cm_id and then kfree the cm_id * object. */ void iw_destroy_cm_id(struct iw_cm_id *cm_id) { if (!destroy_cm_id(cm_id)) flush_workqueue(iwcm_wq); } EXPORT_SYMBOL(iw_destroy_cm_id); /** * iw_cm_check_wildcard - If IP address is 0 then use original * @pm_addr: sockaddr containing the ip to check for wildcard * @cm_addr: sockaddr containing the actual IP address * @cm_outaddr: sockaddr to set IP addr which leaving port * * Checks the pm_addr for wildcard and then sets cm_outaddr's * IP to the actual (cm_addr). */ static void iw_cm_check_wildcard(struct sockaddr_storage *pm_addr, struct sockaddr_storage *cm_addr, struct sockaddr_storage *cm_outaddr) { if (pm_addr->ss_family == AF_INET) { struct sockaddr_in *pm4_addr = (struct sockaddr_in *)pm_addr; if (pm4_addr->sin_addr.s_addr == htonl(INADDR_ANY)) { struct sockaddr_in *cm4_addr = (struct sockaddr_in *)cm_addr; struct sockaddr_in *cm4_outaddr = (struct sockaddr_in *)cm_outaddr; cm4_outaddr->sin_addr = cm4_addr->sin_addr; } } else { struct sockaddr_in6 *pm6_addr = (struct sockaddr_in6 *)pm_addr; if (ipv6_addr_type(&pm6_addr->sin6_addr) == IPV6_ADDR_ANY) { struct sockaddr_in6 *cm6_addr = (struct sockaddr_in6 *)cm_addr; struct sockaddr_in6 *cm6_outaddr = (struct sockaddr_in6 *)cm_outaddr; cm6_outaddr->sin6_addr = cm6_addr->sin6_addr; } } } /** * iw_cm_map - Use portmapper to map the ports * @cm_id: connection manager pointer * @active: Indicates the active side when true * returns nonzero for error only if iwpm_create_mapinfo() fails * * Tries to add a mapping for a port using the Portmapper. If * successful in mapping the IP/Port it will check the remote * mapped IP address for a wildcard IP address and replace the * zero IP address with the remote_addr. */ static int iw_cm_map(struct iw_cm_id *cm_id, bool active) { const char *devname = dev_name(&cm_id->device->dev); const char *ifname = cm_id->device->iw_ifname; struct iwpm_dev_data pm_reg_msg = {}; struct iwpm_sa_data pm_msg; int status; if (strlen(devname) >= sizeof(pm_reg_msg.dev_name) || strlen(ifname) >= sizeof(pm_reg_msg.if_name)) return -EINVAL; cm_id->m_local_addr = cm_id->local_addr; cm_id->m_remote_addr = cm_id->remote_addr; strcpy(pm_reg_msg.dev_name, devname); strcpy(pm_reg_msg.if_name, ifname); if (iwpm_register_pid(&pm_reg_msg, RDMA_NL_IWCM) || !iwpm_valid_pid()) return 0; cm_id->mapped = true; pm_msg.loc_addr = cm_id->local_addr; pm_msg.rem_addr = cm_id->remote_addr; pm_msg.flags = (cm_id->device->iw_driver_flags & IW_F_NO_PORT_MAP) ? IWPM_FLAGS_NO_PORT_MAP : 0; if (active) status = iwpm_add_and_query_mapping(&pm_msg, RDMA_NL_IWCM); else status = iwpm_add_mapping(&pm_msg, RDMA_NL_IWCM); if (!status) { cm_id->m_local_addr = pm_msg.mapped_loc_addr; if (active) { cm_id->m_remote_addr = pm_msg.mapped_rem_addr; iw_cm_check_wildcard(&pm_msg.mapped_rem_addr, &cm_id->remote_addr, &cm_id->m_remote_addr); } } return iwpm_create_mapinfo(&cm_id->local_addr, &cm_id->m_local_addr, RDMA_NL_IWCM, pm_msg.flags); } /* * CM_ID <-- LISTEN * * Start listening for connect requests. Generates one CONNECT_REQUEST * event for each inbound connect request. */ int iw_cm_listen(struct iw_cm_id *cm_id, int backlog) { struct iwcm_id_private *cm_id_priv; unsigned long flags; int ret; cm_id_priv = container_of(cm_id, struct iwcm_id_private, id); if (!backlog) backlog = default_backlog; ret = alloc_work_entries(cm_id_priv, backlog); if (ret) return ret; spin_lock_irqsave(&cm_id_priv->lock, flags); switch (cm_id_priv->state) { case IW_CM_STATE_IDLE: cm_id_priv->state = IW_CM_STATE_LISTEN; spin_unlock_irqrestore(&cm_id_priv->lock, flags); ret = iw_cm_map(cm_id, false); if (!ret) ret = cm_id->device->ops.iw_create_listen(cm_id, backlog); if (ret) cm_id_priv->state = IW_CM_STATE_IDLE; spin_lock_irqsave(&cm_id_priv->lock, flags); break; default: ret = -EINVAL; } spin_unlock_irqrestore(&cm_id_priv->lock, flags); return ret; } EXPORT_SYMBOL(iw_cm_listen); /* * CM_ID <-- IDLE * * Rejects an inbound connection request. No events are generated. */ int iw_cm_reject(struct iw_cm_id *cm_id, const void *private_data, u8 private_data_len) { struct iwcm_id_private *cm_id_priv; unsigned long flags; int ret; cm_id_priv = container_of(cm_id, struct iwcm_id_private, id); set_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags); spin_lock_irqsave(&cm_id_priv->lock, flags); if (cm_id_priv->state != IW_CM_STATE_CONN_RECV) { spin_unlock_irqrestore(&cm_id_priv->lock, flags); clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags); wake_up_all(&cm_id_priv->connect_wait); return -EINVAL; } cm_id_priv->state = IW_CM_STATE_IDLE; spin_unlock_irqrestore(&cm_id_priv->lock, flags); ret = cm_id->device->ops.iw_reject(cm_id, private_data, private_data_len); clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags); wake_up_all(&cm_id_priv->connect_wait); return ret; } EXPORT_SYMBOL(iw_cm_reject); /* * CM_ID <-- ESTABLISHED * * Accepts an inbound connection request and generates an ESTABLISHED * event. Callers of iw_cm_disconnect and iw_destroy_cm_id will block * until the ESTABLISHED event is received from the provider. */ int iw_cm_accept(struct iw_cm_id *cm_id, struct iw_cm_conn_param *iw_param) { struct iwcm_id_private *cm_id_priv; struct ib_qp *qp; unsigned long flags; int ret; cm_id_priv = container_of(cm_id, struct iwcm_id_private, id); set_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags); spin_lock_irqsave(&cm_id_priv->lock, flags); if (cm_id_priv->state != IW_CM_STATE_CONN_RECV) { spin_unlock_irqrestore(&cm_id_priv->lock, flags); clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags); wake_up_all(&cm_id_priv->connect_wait); return -EINVAL; } /* Get the ib_qp given the QPN */ qp = cm_id->device->ops.iw_get_qp(cm_id->device, iw_param->qpn); if (!qp) { spin_unlock_irqrestore(&cm_id_priv->lock, flags); clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags); wake_up_all(&cm_id_priv->connect_wait); return -EINVAL; } cm_id->device->ops.iw_add_ref(qp); cm_id_priv->qp = qp; spin_unlock_irqrestore(&cm_id_priv->lock, flags); ret = cm_id->device->ops.iw_accept(cm_id, iw_param); if (ret) { /* An error on accept precludes provider events */ BUG_ON(cm_id_priv->state != IW_CM_STATE_CONN_RECV); cm_id_priv->state = IW_CM_STATE_IDLE; spin_lock_irqsave(&cm_id_priv->lock, flags); qp = cm_id_priv->qp; cm_id_priv->qp = NULL; spin_unlock_irqrestore(&cm_id_priv->lock, flags); if (qp) cm_id->device->ops.iw_rem_ref(qp); clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags); wake_up_all(&cm_id_priv->connect_wait); } return ret; } EXPORT_SYMBOL(iw_cm_accept); /* * Active Side: CM_ID <-- CONN_SENT * * If successful, results in the generation of a CONNECT_REPLY * event. iw_cm_disconnect and iw_cm_destroy will block until the * CONNECT_REPLY event is received from the provider. */ int iw_cm_connect(struct iw_cm_id *cm_id, struct iw_cm_conn_param *iw_param) { struct iwcm_id_private *cm_id_priv; int ret; unsigned long flags; struct ib_qp *qp = NULL; cm_id_priv = container_of(cm_id, struct iwcm_id_private, id); ret = alloc_work_entries(cm_id_priv, 4); if (ret) return ret; set_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags); spin_lock_irqsave(&cm_id_priv->lock, flags); if (cm_id_priv->state != IW_CM_STATE_IDLE) { ret = -EINVAL; goto err; } /* Get the ib_qp given the QPN */ qp = cm_id->device->ops.iw_get_qp(cm_id->device, iw_param->qpn); if (!qp) { ret = -EINVAL; goto err; } cm_id->device->ops.iw_add_ref(qp); cm_id_priv->qp = qp; cm_id_priv->state = IW_CM_STATE_CONN_SENT; spin_unlock_irqrestore(&cm_id_priv->lock, flags); ret = iw_cm_map(cm_id, true); if (!ret) ret = cm_id->device->ops.iw_connect(cm_id, iw_param); if (!ret) return 0; /* success */ spin_lock_irqsave(&cm_id_priv->lock, flags); qp = cm_id_priv->qp; cm_id_priv->qp = NULL; cm_id_priv->state = IW_CM_STATE_IDLE; err: spin_unlock_irqrestore(&cm_id_priv->lock, flags); if (qp) cm_id->device->ops.iw_rem_ref(qp); clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags); wake_up_all(&cm_id_priv->connect_wait); return ret; } EXPORT_SYMBOL(iw_cm_connect); /* * Passive Side: new CM_ID <-- CONN_RECV * * Handles an inbound connect request. The function creates a new * iw_cm_id to represent the new connection and inherits the client * callback function and other attributes from the listening parent. * * The work item contains a pointer to the listen_cm_id and the event. The * listen_cm_id contains the client cm_handler, context and * device. These are copied when the device is cloned. The event * contains the new four tuple. * * An error on the child should not affect the parent, so this * function does not return a value. */ static void cm_conn_req_handler(struct iwcm_id_private *listen_id_priv, struct iw_cm_event *iw_event) { unsigned long flags; struct iw_cm_id *cm_id; struct iwcm_id_private *cm_id_priv; int ret; /* * The provider should never generate a connection request * event with a bad status. */ BUG_ON(iw_event->status); cm_id = iw_create_cm_id(listen_id_priv->id.device, listen_id_priv->id.cm_handler, listen_id_priv->id.context); /* If the cm_id could not be created, ignore the request */ if (IS_ERR(cm_id)) goto out; cm_id->provider_data = iw_event->provider_data; cm_id->m_local_addr = iw_event->local_addr; cm_id->m_remote_addr = iw_event->remote_addr; cm_id->local_addr = listen_id_priv->id.local_addr; ret = iwpm_get_remote_info(&listen_id_priv->id.m_local_addr, &iw_event->remote_addr, &cm_id->remote_addr, RDMA_NL_IWCM); if (ret) { cm_id->remote_addr = iw_event->remote_addr; } else { iw_cm_check_wildcard(&listen_id_priv->id.m_local_addr, &iw_event->local_addr, &cm_id->local_addr); iw_event->local_addr = cm_id->local_addr; iw_event->remote_addr = cm_id->remote_addr; } cm_id_priv = container_of(cm_id, struct iwcm_id_private, id); cm_id_priv->state = IW_CM_STATE_CONN_RECV; /* * We could be destroying the listening id. If so, ignore this * upcall. */ spin_lock_irqsave(&listen_id_priv->lock, flags); if (listen_id_priv->state != IW_CM_STATE_LISTEN) { spin_unlock_irqrestore(&listen_id_priv->lock, flags); iw_cm_reject(cm_id, NULL, 0); iw_destroy_cm_id(cm_id); goto out; } spin_unlock_irqrestore(&listen_id_priv->lock, flags); ret = alloc_work_entries(cm_id_priv, 3); if (ret) { iw_cm_reject(cm_id, NULL, 0); iw_destroy_cm_id(cm_id); goto out; } /* Call the client CM handler */ ret = cm_id->cm_handler(cm_id, iw_event); if (ret) { iw_cm_reject(cm_id, NULL, 0); iw_destroy_cm_id(cm_id); } out: if (iw_event->private_data_len) kfree(iw_event->private_data); } /* * Passive Side: CM_ID <-- ESTABLISHED * * The provider generated an ESTABLISHED event which means that * the MPA negotion has completed successfully and we are now in MPA * FPDU mode. * * This event can only be received in the CONN_RECV state. If the * remote peer closed, the ESTABLISHED event would be received followed * by the CLOSE event. If the app closes, it will block until we wake * it up after processing this event. */ static int cm_conn_est_handler(struct iwcm_id_private *cm_id_priv, struct iw_cm_event *iw_event) { unsigned long flags; int ret; spin_lock_irqsave(&cm_id_priv->lock, flags); /* * We clear the CONNECT_WAIT bit here to allow the callback * function to call iw_cm_disconnect. Calling iw_destroy_cm_id * from a callback handler is not allowed. */ clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags); BUG_ON(cm_id_priv->state != IW_CM_STATE_CONN_RECV); cm_id_priv->state = IW_CM_STATE_ESTABLISHED; spin_unlock_irqrestore(&cm_id_priv->lock, flags); ret = cm_id_priv->id.cm_handler(&cm_id_priv->id, iw_event); wake_up_all(&cm_id_priv->connect_wait); return ret; } /* * Active Side: CM_ID <-- ESTABLISHED * * The app has called connect and is waiting for the established event to * post it's requests to the server. This event will wake up anyone * blocked in iw_cm_disconnect or iw_destroy_id. */ static int cm_conn_rep_handler(struct iwcm_id_private *cm_id_priv, struct iw_cm_event *iw_event) { struct ib_qp *qp = NULL; unsigned long flags; int ret; spin_lock_irqsave(&cm_id_priv->lock, flags); /* * Clear the connect wait bit so a callback function calling * iw_cm_disconnect will not wait and deadlock this thread */ clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags); BUG_ON(cm_id_priv->state != IW_CM_STATE_CONN_SENT); if (iw_event->status == 0) { cm_id_priv->id.m_local_addr = iw_event->local_addr; cm_id_priv->id.m_remote_addr = iw_event->remote_addr; iw_event->local_addr = cm_id_priv->id.local_addr; iw_event->remote_addr = cm_id_priv->id.remote_addr; cm_id_priv->state = IW_CM_STATE_ESTABLISHED; } else { /* REJECTED or RESET */ qp = cm_id_priv->qp; cm_id_priv->qp = NULL; cm_id_priv->state = IW_CM_STATE_IDLE; } spin_unlock_irqrestore(&cm_id_priv->lock, flags); if (qp) cm_id_priv->id.device->ops.iw_rem_ref(qp); ret = cm_id_priv->id.cm_handler(&cm_id_priv->id, iw_event); if (iw_event->private_data_len) kfree(iw_event->private_data); /* Wake up waiters on connect complete */ wake_up_all(&cm_id_priv->connect_wait); return ret; } /* * CM_ID <-- CLOSING * * If in the ESTABLISHED state, move to CLOSING. */ static void cm_disconnect_handler(struct iwcm_id_private *cm_id_priv, struct iw_cm_event *iw_event) { unsigned long flags; spin_lock_irqsave(&cm_id_priv->lock, flags); if (cm_id_priv->state == IW_CM_STATE_ESTABLISHED) cm_id_priv->state = IW_CM_STATE_CLOSING; spin_unlock_irqrestore(&cm_id_priv->lock, flags); } /* * CM_ID <-- IDLE * * If in the ESTBLISHED or CLOSING states, the QP will have have been * moved by the provider to the ERR state. Disassociate the CM_ID from * the QP, move to IDLE, and remove the 'connected' reference. * * If in some other state, the cm_id was destroyed asynchronously. * This is the last reference that will result in waking up * the app thread blocked in iw_destroy_cm_id. */ static int cm_close_handler(struct iwcm_id_private *cm_id_priv, struct iw_cm_event *iw_event) { struct ib_qp *qp; unsigned long flags; int ret = 0, notify_event = 0; spin_lock_irqsave(&cm_id_priv->lock, flags); qp = cm_id_priv->qp; cm_id_priv->qp = NULL; switch (cm_id_priv->state) { case IW_CM_STATE_ESTABLISHED: case IW_CM_STATE_CLOSING: cm_id_priv->state = IW_CM_STATE_IDLE; notify_event = 1; break; case IW_CM_STATE_DESTROYING: break; default: BUG(); } spin_unlock_irqrestore(&cm_id_priv->lock, flags); if (qp) cm_id_priv->id.device->ops.iw_rem_ref(qp); if (notify_event) ret = cm_id_priv->id.cm_handler(&cm_id_priv->id, iw_event); return ret; } static int process_event(struct iwcm_id_private *cm_id_priv, struct iw_cm_event *iw_event) { int ret = 0; switch (iw_event->event) { case IW_CM_EVENT_CONNECT_REQUEST: cm_conn_req_handler(cm_id_priv, iw_event); break; case IW_CM_EVENT_CONNECT_REPLY: ret = cm_conn_rep_handler(cm_id_priv, iw_event); break; case IW_CM_EVENT_ESTABLISHED: ret = cm_conn_est_handler(cm_id_priv, iw_event); break; case IW_CM_EVENT_DISCONNECT: cm_disconnect_handler(cm_id_priv, iw_event); break; case IW_CM_EVENT_CLOSE: ret = cm_close_handler(cm_id_priv, iw_event); break; default: BUG(); } return ret; } /* * Process events on the work_list for the cm_id. If the callback * function requests that the cm_id be deleted, a flag is set in the * cm_id flags to indicate that when the last reference is * removed, the cm_id is to be destroyed. This is necessary to * distinguish between an object that will be destroyed by the app * thread asleep on the destroy_comp list vs. an object destroyed * here synchronously when the last reference is removed. */ static void cm_work_handler(struct work_struct *_work) { struct iwcm_work *work = container_of(_work, struct iwcm_work, work); struct iw_cm_event levent; struct iwcm_id_private *cm_id_priv = work->cm_id; unsigned long flags; int empty; int ret = 0; spin_lock_irqsave(&cm_id_priv->lock, flags); empty = list_empty(&cm_id_priv->work_list); while (!empty) { work = list_entry(cm_id_priv->work_list.next, struct iwcm_work, list); list_del_init(&work->list); empty = list_empty(&cm_id_priv->work_list); levent = work->event; put_work(work); spin_unlock_irqrestore(&cm_id_priv->lock, flags); if (!test_bit(IWCM_F_DROP_EVENTS, &cm_id_priv->flags)) { ret = process_event(cm_id_priv, &levent); if (ret) WARN_ON_ONCE(destroy_cm_id(&cm_id_priv->id)); } else pr_debug("dropping event %d\n", levent.event); if (iwcm_deref_id(cm_id_priv)) return; if (empty) return; spin_lock_irqsave(&cm_id_priv->lock, flags); } spin_unlock_irqrestore(&cm_id_priv->lock, flags); } /* * This function is called on interrupt context. Schedule events on * the iwcm_wq thread to allow callback functions to downcall into * the CM and/or block. Events are queued to a per-CM_ID * work_list. If this is the first event on the work_list, the work * element is also queued on the iwcm_wq thread. * * Each event holds a reference on the cm_id. Until the last posted * event has been delivered and processed, the cm_id cannot be * deleted. * * Returns: * 0 - the event was handled. * -ENOMEM - the event was not handled due to lack of resources. */ static int cm_event_handler(struct iw_cm_id *cm_id, struct iw_cm_event *iw_event) { struct iwcm_work *work; struct iwcm_id_private *cm_id_priv; unsigned long flags; int ret = 0; cm_id_priv = container_of(cm_id, struct iwcm_id_private, id); spin_lock_irqsave(&cm_id_priv->lock, flags); work = get_work(cm_id_priv); if (!work) { ret = -ENOMEM; goto out; } INIT_WORK(&work->work, cm_work_handler); work->cm_id = cm_id_priv; work->event = *iw_event; if ((work->event.event == IW_CM_EVENT_CONNECT_REQUEST || work->event.event == IW_CM_EVENT_CONNECT_REPLY) && work->event.private_data_len) { ret = copy_private_data(&work->event); if (ret) { put_work(work); goto out; } } refcount_inc(&cm_id_priv->refcount); if (list_empty(&cm_id_priv->work_list)) { list_add_tail(&work->list, &cm_id_priv->work_list); queue_work(iwcm_wq, &work->work); } else list_add_tail(&work->list, &cm_id_priv->work_list); out: spin_unlock_irqrestore(&cm_id_priv->lock, flags); return ret; } static int iwcm_init_qp_init_attr(struct iwcm_id_private *cm_id_priv, struct ib_qp_attr *qp_attr, int *qp_attr_mask) { unsigned long flags; int ret; spin_lock_irqsave(&cm_id_priv->lock, flags); switch (cm_id_priv->state) { case IW_CM_STATE_IDLE: case IW_CM_STATE_CONN_SENT: case IW_CM_STATE_CONN_RECV: case IW_CM_STATE_ESTABLISHED: *qp_attr_mask = IB_QP_STATE | IB_QP_ACCESS_FLAGS; qp_attr->qp_access_flags = IB_ACCESS_REMOTE_WRITE| IB_ACCESS_REMOTE_READ; ret = 0; break; default: ret = -EINVAL; break; } spin_unlock_irqrestore(&cm_id_priv->lock, flags); return ret; } static int iwcm_init_qp_rts_attr(struct iwcm_id_private *cm_id_priv, struct ib_qp_attr *qp_attr, int *qp_attr_mask) { unsigned long flags; int ret; spin_lock_irqsave(&cm_id_priv->lock, flags); switch (cm_id_priv->state) { case IW_CM_STATE_IDLE: case IW_CM_STATE_CONN_SENT: case IW_CM_STATE_CONN_RECV: case IW_CM_STATE_ESTABLISHED: *qp_attr_mask = 0; ret = 0; break; default: ret = -EINVAL; break; } spin_unlock_irqrestore(&cm_id_priv->lock, flags); return ret; } int iw_cm_init_qp_attr(struct iw_cm_id *cm_id, struct ib_qp_attr *qp_attr, int *qp_attr_mask) { struct iwcm_id_private *cm_id_priv; int ret; cm_id_priv = container_of(cm_id, struct iwcm_id_private, id); switch (qp_attr->qp_state) { case IB_QPS_INIT: case IB_QPS_RTR: ret = iwcm_init_qp_init_attr(cm_id_priv, qp_attr, qp_attr_mask); break; case IB_QPS_RTS: ret = iwcm_init_qp_rts_attr(cm_id_priv, qp_attr, qp_attr_mask); break; default: ret = -EINVAL; break; } return ret; } EXPORT_SYMBOL(iw_cm_init_qp_attr); static int __init iw_cm_init(void) { int ret; ret = iwpm_init(RDMA_NL_IWCM); if (ret) return ret; iwcm_wq = alloc_ordered_workqueue("iw_cm_wq", WQ_MEM_RECLAIM); if (!iwcm_wq) goto err_alloc; iwcm_ctl_table_hdr = register_net_sysctl(&init_net, "net/iw_cm", iwcm_ctl_table); if (!iwcm_ctl_table_hdr) { pr_err("iw_cm: couldn't register sysctl paths\n"); goto err_sysctl; } rdma_nl_register(RDMA_NL_IWCM, iwcm_nl_cb_table); return 0; err_sysctl: destroy_workqueue(iwcm_wq); err_alloc: iwpm_exit(RDMA_NL_IWCM); return -ENOMEM; } static void __exit iw_cm_cleanup(void) { rdma_nl_unregister(RDMA_NL_IWCM); unregister_net_sysctl_table(iwcm_ctl_table_hdr); destroy_workqueue(iwcm_wq); iwpm_exit(RDMA_NL_IWCM); } MODULE_ALIAS_RDMA_NETLINK(RDMA_NL_IWCM, 2); module_init(iw_cm_init); module_exit(iw_cm_cleanup);