drivers/ntb/ntb.c

   1 /*
   2  * This file is provided under a dual BSD/GPLv2 license.  When using or
   3  *   redistributing this file, you may do so under either license.
   4  *
   5  *   GPL LICENSE SUMMARY
   6  *
   7  *   Copyright (C) 2015 EMC Corporation. All Rights Reserved.
   8  *   Copyright (C) 2016 T-Platforms. All Rights Reserved.
   9  *
  10  *   This program is free software; you can redistribute it and/or modify
  11  *   it under the terms of version 2 of the GNU General Public License as
  12  *   published by the Free Software Foundation.
  13  *
  14  *   This program is distributed in the hope that it will be useful, but
  15  *   WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  *   General Public License for more details.
  18  *
  19  *   BSD LICENSE
  20  *
  21  *   Copyright (C) 2015 EMC Corporation. All Rights Reserved.
  22  *   Copyright (C) 2016 T-Platforms. All Rights Reserved.
  23  *
  24  *   Redistribution and use in source and binary forms, with or without
  25  *   modification, are permitted provided that the following conditions
  26  *   are met:
  27  *
  28  *     * Redistributions of source code must retain the above copyright
  29  *       notice, this list of conditions and the following disclaimer.
  30  *     * Redistributions in binary form must reproduce the above copy
  31  *       notice, this list of conditions and the following disclaimer in
  32  *       the documentation and/or other materials provided with the
  33  *       distribution.
  34  *     * Neither the name of Intel Corporation nor the names of its
  35  *       contributors may be used to endorse or promote products derived
  36  *       from this software without specific prior written permission.
  37  *
  38  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  39  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  40  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  41  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  42  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  43  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  44  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  45  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  46  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  47  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  48  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  49  *
  50  * PCIe NTB Linux driver
  51  *
  52  * Contact Information:
  53  * Allen Hubbe <Allen.Hubbe@emc.com>
  54  */
  55
  56 #include <linux/device.h>
  57 #include <linux/kernel.h>
  58 #include <linux/module.h>
  59
  60 #include <linux/ntb.h>
  61 #include <linux/pci.h>
  62
  63 #define DRIVER_NAME                     "ntb"
  64 #define DRIVER_DESCRIPTION              "PCIe NTB Driver Framework"
  65
  66 #define DRIVER_LICENSE                  "Dual BSD/GPL"
  67 #define DRIVER_VERSION                  "1.0"
  68 #define DRIVER_RELDATE                  "24 March 2015"
  69 #define DRIVER_AUTHOR                   "Allen Hubbe <Allen.Hubbe@emc.com>"
  70
  71 MODULE_LICENSE(DRIVER_LICENSE);
  72 MODULE_VERSION(DRIVER_VERSION);
  73 MODULE_AUTHOR(DRIVER_AUTHOR);
  74 MODULE_DESCRIPTION(DRIVER_DESCRIPTION);
  75
  76 static struct bus_type ntb_bus;
  77 static void ntb_dev_release(struct device *dev);
  78
  79 int __ntb_register_client(struct ntb_client *client, struct module *mod,
  80                           const char *mod_name)
  81 {
  82         if (!client)
  83                 return -EINVAL;
  84         if (!ntb_client_ops_is_valid(&client->ops))
  85                 return -EINVAL;
  86
  87         memset(&client->drv, 0, sizeof(client->drv));
  88         client->drv.bus = &ntb_bus;
  89         client->drv.name = mod_name;
  90         client->drv.owner = mod;
  91
  92         return driver_register(&client->drv);
  93 }
  94 EXPORT_SYMBOL(__ntb_register_client);
  95
  96 void ntb_unregister_client(struct ntb_client *client)
  97 {
  98         driver_unregister(&client->drv);
  99 }
 100 EXPORT_SYMBOL(ntb_unregister_client);
 101
 102 int ntb_register_device(struct ntb_dev *ntb)
 103 {
 104         if (!ntb)
 105                 return -EINVAL;
 106         if (!ntb->pdev)
 107                 return -EINVAL;
 108         if (!ntb->ops)
 109                 return -EINVAL;
 110         if (!ntb_dev_ops_is_valid(ntb->ops))
 111                 return -EINVAL;
 112
 113         init_completion(&ntb->released);
 114
 115         memset(&ntb->dev, 0, sizeof(ntb->dev));
 116         ntb->dev.bus = &ntb_bus;
 117         ntb->dev.parent = &ntb->pdev->dev;
 118         ntb->dev.release = ntb_dev_release;
 119         dev_set_name(&ntb->dev, "%s", pci_name(ntb->pdev));
 120
 121         ntb->ctx = NULL;
 122         ntb->ctx_ops = NULL;
 123         spin_lock_init(&ntb->ctx_lock);
 124
 125         return device_register(&ntb->dev);
 126 }
 127 EXPORT_SYMBOL(ntb_register_device);
 128
 129 void ntb_unregister_device(struct ntb_dev *ntb)
 130 {
 131         device_unregister(&ntb->dev);
 132         wait_for_completion(&ntb->released);
 133 }
 134 EXPORT_SYMBOL(ntb_unregister_device);
 135
 136 int ntb_set_ctx(struct ntb_dev *ntb, void *ctx,
 137                 const struct ntb_ctx_ops *ctx_ops)
 138 {
 139         unsigned long irqflags;
 140
 141         if (!ntb_ctx_ops_is_valid(ctx_ops))
 142                 return -EINVAL;
 143         if (ntb->ctx_ops)
 144                 return -EINVAL;
 145
 146         spin_lock_irqsave(&ntb->ctx_lock, irqflags);
 147         {
 148                 ntb->ctx = ctx;
 149                 ntb->ctx_ops = ctx_ops;
 150         }
 151         spin_unlock_irqrestore(&ntb->ctx_lock, irqflags);
 152
 153         return 0;
 154 }
 155 EXPORT_SYMBOL(ntb_set_ctx);
 156
 157 void ntb_clear_ctx(struct ntb_dev *ntb)
 158 {
 159         unsigned long irqflags;
 160
 161         spin_lock_irqsave(&ntb->ctx_lock, irqflags);
 162         {
 163                 ntb->ctx_ops = NULL;
 164                 ntb->ctx = NULL;
 165         }
 166         spin_unlock_irqrestore(&ntb->ctx_lock, irqflags);
 167 }
 168 EXPORT_SYMBOL(ntb_clear_ctx);
 169
 170 void ntb_link_event(struct ntb_dev *ntb)
 171 {
 172         unsigned long irqflags;
 173
 174         spin_lock_irqsave(&ntb->ctx_lock, irqflags);
 175         {
 176                 if (ntb->ctx_ops && ntb->ctx_ops->link_event)
 177                         ntb->ctx_ops->link_event(ntb->ctx);
 178         }
 179         spin_unlock_irqrestore(&ntb->ctx_lock, irqflags);
 180 }
 181 EXPORT_SYMBOL(ntb_link_event);
 182
 183 void ntb_db_event(struct ntb_dev *ntb, int vector)
 184 {
 185         unsigned long irqflags;
 186
 187         spin_lock_irqsave(&ntb->ctx_lock, irqflags);
 188         {
 189                 if (ntb->ctx_ops && ntb->ctx_ops->db_event)
 190                         ntb->ctx_ops->db_event(ntb->ctx, vector);
 191         }
 192         spin_unlock_irqrestore(&ntb->ctx_lock, irqflags);
 193 }
 194 EXPORT_SYMBOL(ntb_db_event);
 195
 196 void ntb_msg_event(struct ntb_dev *ntb)
 197 {
 198         unsigned long irqflags;
 199
 200         spin_lock_irqsave(&ntb->ctx_lock, irqflags);
 201         {
 202                 if (ntb->ctx_ops && ntb->ctx_ops->msg_event)
 203                         ntb->ctx_ops->msg_event(ntb->ctx);
 204         }
 205         spin_unlock_irqrestore(&ntb->ctx_lock, irqflags);
 206 }
 207 EXPORT_SYMBOL(ntb_msg_event);
 208
 209 int ntb_default_port_number(struct ntb_dev *ntb)
 210 {
 211         switch (ntb->topo) {
 212         case NTB_TOPO_PRI:
 213         case NTB_TOPO_B2B_USD:
 214                 return NTB_PORT_PRI_USD;
 215         case NTB_TOPO_SEC:
 216         case NTB_TOPO_B2B_DSD:
 217                 return NTB_PORT_SEC_DSD;
 218         default:
 219                 break;
 220         }
 221
 222         return -EINVAL;
 223 }
 224 EXPORT_SYMBOL(ntb_default_port_number);
 225
 226 int ntb_default_peer_port_count(struct ntb_dev *ntb)
 227 {
 228         return NTB_DEF_PEER_CNT;
 229 }
 230 EXPORT_SYMBOL(ntb_default_peer_port_count);
 231
 232 int ntb_default_peer_port_number(struct ntb_dev *ntb, int pidx)
 233 {
 234         if (pidx != NTB_DEF_PEER_IDX)
 235                 return -EINVAL;
 236
 237         switch (ntb->topo) {
 238         case NTB_TOPO_PRI:
 239         case NTB_TOPO_B2B_USD:
 240                 return NTB_PORT_SEC_DSD;
 241         case NTB_TOPO_SEC:
 242         case NTB_TOPO_B2B_DSD:
 243                 return NTB_PORT_PRI_USD;
 244         default:
 245                 break;
 246         }
 247
 248         return -EINVAL;
 249 }
 250 EXPORT_SYMBOL(ntb_default_peer_port_number);
 251
 252 int ntb_default_peer_port_idx(struct ntb_dev *ntb, int port)
 253 {
 254         int peer_port = ntb_default_peer_port_number(ntb, NTB_DEF_PEER_IDX);
 255
 256         if (peer_port == -EINVAL || port != peer_port)
 257                 return -EINVAL;
 258
 259         return 0;
 260 }
 261 EXPORT_SYMBOL(ntb_default_peer_port_idx);
 262
 263 static int ntb_probe(struct device *dev)
 264 {
 265         struct ntb_dev *ntb;
 266         struct ntb_client *client;
 267         int rc;
 268
 269         get_device(dev);
 270         ntb = dev_ntb(dev);
 271         client = drv_ntb_client(dev->driver);
 272
 273         rc = client->ops.probe(client, ntb);
 274         if (rc)
 275                 put_device(dev);
 276
 277         return rc;
 278 }
 279
 280 static int ntb_remove(struct device *dev)
 281 {
 282         struct ntb_dev *ntb;
 283         struct ntb_client *client;
 284
 285         if (dev->driver) {
 286                 ntb = dev_ntb(dev);
 287                 client = drv_ntb_client(dev->driver);
 288
 289                 client->ops.remove(client, ntb);
 290                 put_device(dev);
 291         }
 292
 293         return 0;
 294 }
 295
 296 static void ntb_dev_release(struct device *dev)
 297 {
 298         struct ntb_dev *ntb = dev_ntb(dev);
 299
 300         complete(&ntb->released);
 301 }
 302
 303 static struct bus_type ntb_bus = {
 304         .name = "ntb",
 305         .probe = ntb_probe,
 306         .remove = ntb_remove,
 307 };
 308
 309 static int __init ntb_driver_init(void)
 310 {
 311         return bus_register(&ntb_bus);
 312 }
 313 module_init(ntb_driver_init);
 314
 315 static void __exit ntb_driver_exit(void)
 316 {
 317         bus_unregister(&ntb_bus);
 318 }
 319 module_exit(ntb_driver_exit);
 320