drivers/misc/mic/scif/scif_nm.c

   1 /*
   2  * Intel MIC Platform Software Stack (MPSS)
   3  *
   4  * Copyright(c) 2014 Intel Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License, version 2, as
   8  * published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  13  * General Public License for more details.
  14  *
  15  * Intel SCIF driver.
  16  *
  17  */
  18 #include "scif_peer_bus.h"
  19
  20 #include "scif_main.h"
  21 #include "scif_map.h"
  22
  23 /**
  24  * scif_invalidate_ep() - Set state for all connected endpoints
  25  * to disconnected and wake up all send/recv waitqueues
  26  */
  27 static void scif_invalidate_ep(int node)
  28 {
  29         struct scif_endpt *ep;
  30         struct list_head *pos, *tmpq;
  31
  32         flush_work(&scif_info.conn_work);
  33         mutex_lock(&scif_info.connlock);
  34         list_for_each_safe(pos, tmpq, &scif_info.disconnected) {
  35                 ep = list_entry(pos, struct scif_endpt, list);
  36                 if (ep->remote_dev->node == node) {
  37                         spin_lock(&ep->lock);
  38                         scif_cleanup_ep_qp(ep);
  39                         spin_unlock(&ep->lock);
  40                 }
  41         }
  42         list_for_each_safe(pos, tmpq, &scif_info.connected) {
  43                 ep = list_entry(pos, struct scif_endpt, list);
  44                 if (ep->remote_dev->node == node) {
  45                         list_del(pos);
  46                         spin_lock(&ep->lock);
  47                         ep->state = SCIFEP_DISCONNECTED;
  48                         list_add_tail(&ep->list, &scif_info.disconnected);
  49                         scif_cleanup_ep_qp(ep);
  50                         wake_up_interruptible(&ep->sendwq);
  51                         wake_up_interruptible(&ep->recvwq);
  52                         spin_unlock(&ep->lock);
  53                 }
  54         }
  55         mutex_unlock(&scif_info.connlock);
  56 }
  57
  58 void scif_free_qp(struct scif_dev *scifdev)
  59 {
  60         struct scif_qp *qp = scifdev->qpairs;
  61
  62         if (!qp)
  63                 return;
  64         scif_free_coherent((void *)qp->inbound_q.rb_base,
  65                            qp->local_buf, scifdev, qp->inbound_q.size);
  66         scif_unmap_single(qp->local_qp, scifdev, sizeof(struct scif_qp));
  67         kfree(scifdev->qpairs);
  68         scifdev->qpairs = NULL;
  69 }
  70
  71 static void scif_cleanup_qp(struct scif_dev *dev)
  72 {
  73         struct scif_qp *qp = &dev->qpairs[0];
  74
  75         if (!qp)
  76                 return;
  77         scif_iounmap((void *)qp->remote_qp, sizeof(struct scif_qp), dev);
  78         scif_iounmap((void *)qp->outbound_q.rb_base,
  79                      sizeof(struct scif_qp), dev);
  80         qp->remote_qp = NULL;
  81         qp->local_write = 0;
  82         qp->inbound_q.current_write_offset = 0;
  83         qp->inbound_q.current_read_offset = 0;
  84         if (scifdev_is_p2p(dev))
  85                 scif_free_qp(dev);
  86 }
  87
  88 void scif_send_acks(struct scif_dev *dev)
  89 {
  90         struct scifmsg msg;
  91
  92         if (dev->node_remove_ack_pending) {
  93                 msg.uop = SCIF_NODE_REMOVE_ACK;
  94                 msg.src.node = scif_info.nodeid;
  95                 msg.dst.node = SCIF_MGMT_NODE;
  96                 msg.payload[0] = dev->node;
  97                 scif_nodeqp_send(&scif_dev[SCIF_MGMT_NODE], &msg);
  98                 dev->node_remove_ack_pending = false;
  99         }
 100         if (dev->exit_ack_pending) {
 101                 msg.uop = SCIF_EXIT_ACK;
 102                 msg.src.node = scif_info.nodeid;
 103                 msg.dst.node = dev->node;
 104                 scif_nodeqp_send(dev, &msg);
 105                 dev->exit_ack_pending = false;
 106         }
 107 }
 108
 109 /*
 110  * scif_cleanup_scifdev
 111  *
 112  * @dev: Remote SCIF device.
 113  * Uninitialize SCIF data structures for remote SCIF device.
 114  */
 115 void scif_cleanup_scifdev(struct scif_dev *dev)
 116 {
 117         struct scif_hw_dev *sdev = dev->sdev;
 118
 119         if (!dev->sdev)
 120                 return;
 121         if (scifdev_is_p2p(dev)) {
 122                 if (dev->cookie) {
 123                         sdev->hw_ops->free_irq(sdev, dev->cookie, dev);
 124                         dev->cookie = NULL;
 125                 }
 126                 scif_destroy_intr_wq(dev);
 127         }
 128         scif_destroy_p2p(dev);
 129         scif_invalidate_ep(dev->node);
 130         scif_send_acks(dev);
 131         if (!dev->node && scif_info.card_initiated_exit) {
 132                 /*
 133                  * Send an SCIF_EXIT message which is the last message from MIC
 134                  * to the Host and wait for a SCIF_EXIT_ACK
 135                  */
 136                 scif_send_exit(dev);
 137                 scif_info.card_initiated_exit = false;
 138         }
 139         scif_cleanup_qp(dev);
 140 }
 141
 142 /*
 143  * scif_remove_node:
 144  *
 145  * @node: Node to remove
 146  */
 147 void scif_handle_remove_node(int node)
 148 {
 149         struct scif_dev *scifdev = &scif_dev[node];
 150         struct scif_peer_dev *spdev;
 151
 152         rcu_read_lock();
 153         spdev = rcu_dereference(scifdev->spdev);
 154         rcu_read_unlock();
 155         if (spdev)
 156                 scif_peer_unregister_device(spdev);
 157         else
 158                 scif_send_acks(scifdev);
 159 }
 160
 161 static int scif_send_rmnode_msg(int node, int remove_node)
 162 {
 163         struct scifmsg notif_msg;
 164         struct scif_dev *dev = &scif_dev[node];
 165
 166         notif_msg.uop = SCIF_NODE_REMOVE;
 167         notif_msg.src.node = scif_info.nodeid;
 168         notif_msg.dst.node = node;
 169         notif_msg.payload[0] = remove_node;
 170         return scif_nodeqp_send(dev, &notif_msg);
 171 }
 172
 173 /**
 174  * scif_node_disconnect:
 175  *
 176  * @node_id[in]: source node id.
 177  * @mgmt_initiated: Disconnection initiated from the mgmt node
 178  *
 179  * Disconnect a node from the scif network.
 180  */
 181 void scif_disconnect_node(u32 node_id, bool mgmt_initiated)
 182 {
 183         int ret;
 184         int msg_cnt = 0;
 185         u32 i = 0;
 186         struct scif_dev *scifdev = &scif_dev[node_id];
 187
 188         if (!node_id)
 189                 return;
 190
 191         atomic_set(&scifdev->disconn_rescnt, 0);
 192
 193         /* Destroy p2p network */
 194         for (i = 1; i <= scif_info.maxid; i++) {
 195                 if (i == node_id)
 196                         continue;
 197                 ret = scif_send_rmnode_msg(i, node_id);
 198                 if (!ret)
 199                         msg_cnt++;
 200         }
 201         /* Wait for the remote nodes to respond with SCIF_NODE_REMOVE_ACK */
 202         ret = wait_event_timeout(scifdev->disconn_wq,
 203                                  (atomic_read(&scifdev->disconn_rescnt)
 204                                  == msg_cnt), SCIF_NODE_ALIVE_TIMEOUT);
 205         /* Tell the card to clean up */
 206         if (mgmt_initiated && _scifdev_alive(scifdev))
 207                 /*
 208                  * Send an SCIF_EXIT message which is the last message from Host
 209                  * to the MIC and wait for a SCIF_EXIT_ACK
 210                  */
 211                 scif_send_exit(scifdev);
 212         atomic_set(&scifdev->disconn_rescnt, 0);
 213         /* Tell the mgmt node to clean up */
 214         ret = scif_send_rmnode_msg(SCIF_MGMT_NODE, node_id);
 215         if (!ret)
 216                 /* Wait for mgmt node to respond with SCIF_NODE_REMOVE_ACK */
 217                 wait_event_timeout(scifdev->disconn_wq,
 218                                    (atomic_read(&scifdev->disconn_rescnt) == 1),
 219                                    SCIF_NODE_ALIVE_TIMEOUT);
 220 }
 221
 222 void scif_get_node_info(void)
 223 {
 224         struct scifmsg msg;
 225         DECLARE_COMPLETION_ONSTACK(node_info);
 226
 227         msg.uop = SCIF_GET_NODE_INFO;
 228         msg.src.node = scif_info.nodeid;
 229         msg.dst.node = SCIF_MGMT_NODE;
 230         msg.payload[3] = (u64)&node_info;
 231
 232         if ((scif_nodeqp_send(&scif_dev[SCIF_MGMT_NODE], &msg)))
 233                 return;
 234
 235         /* Wait for a response with SCIF_GET_NODE_INFO */
 236         wait_for_completion(&node_info);
 237 }