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_VERSION                  "1.0"
  67 #define DRIVER_RELDATE                  "24 March 2015"
  68 #define DRIVER_AUTHOR                   "Allen Hubbe <Allen.Hubbe@emc.com>"
  69
  70 MODULE_LICENSE("Dual BSD/GPL");
  71 MODULE_VERSION(DRIVER_VERSION);
  72 MODULE_AUTHOR(DRIVER_AUTHOR);
  73 MODULE_DESCRIPTION(DRIVER_DESCRIPTION);
  74
  75 static struct bus_type ntb_bus;
  76 static void ntb_dev_release(struct device *dev);
  77
  78 int __ntb_register_client(struct ntb_client *client, struct module *mod,
  79                           const char *mod_name)
  80 {
  81         if (!client)
  82                 return -EINVAL;
  83         if (!ntb_client_ops_is_valid(&client->ops))
  84                 return -EINVAL;
  85
  86         memset(&client->drv, 0, sizeof(client->drv));
  87         client->drv.bus = &ntb_bus;
  88         client->drv.name = mod_name;
  89         client->drv.owner = mod;
  90
  91         return driver_register(&client->drv);
  92 }
  93 EXPORT_SYMBOL(__ntb_register_client);
  94
  95 void ntb_unregister_client(struct ntb_client *client)
  96 {
  97         driver_unregister(&client->drv);
  98 }
  99 EXPORT_SYMBOL(ntb_unregister_client);
 100
 101 int ntb_register_device(struct ntb_dev *ntb)
 102 {
 103         if (!ntb)
 104                 return -EINVAL;
 105         if (!ntb->pdev)
 106                 return -EINVAL;
 107         if (!ntb->ops)
 108                 return -EINVAL;
 109         if (!ntb_dev_ops_is_valid(ntb->ops))
 110                 return -EINVAL;
 111
 112         init_completion(&ntb->released);
 113
 114         ntb->dev.bus = &ntb_bus;
 115         ntb->dev.parent = &ntb->pdev->dev;
 116         ntb->dev.release = ntb_dev_release;
 117         dev_set_name(&ntb->dev, "%s", pci_name(ntb->pdev));
 118
 119         ntb->ctx = NULL;
 120         ntb->ctx_ops = NULL;
 121         spin_lock_init(&ntb->ctx_lock);
 122
 123         return device_register(&ntb->dev);
 124 }
 125 EXPORT_SYMBOL(ntb_register_device);
 126
 127 void ntb_unregister_device(struct ntb_dev *ntb)
 128 {
 129         device_unregister(&ntb->dev);
 130         wait_for_completion(&ntb->released);
 131 }
 132 EXPORT_SYMBOL(ntb_unregister_device);
 133
 134 int ntb_set_ctx(struct ntb_dev *ntb, void *ctx,
 135                 const struct ntb_ctx_ops *ctx_ops)
 136 {
 137         unsigned long irqflags;
 138
 139         if (!ntb_ctx_ops_is_valid(ctx_ops))
 140                 return -EINVAL;
 141         if (ntb->ctx_ops)
 142                 return -EINVAL;
 143
 144         spin_lock_irqsave(&ntb->ctx_lock, irqflags);
 145         {
 146                 ntb->ctx = ctx;
 147                 ntb->ctx_ops = ctx_ops;
 148         }
 149         spin_unlock_irqrestore(&ntb->ctx_lock, irqflags);
 150
 151         return 0;
 152 }
 153 EXPORT_SYMBOL(ntb_set_ctx);
 154
 155 void ntb_clear_ctx(struct ntb_dev *ntb)
 156 {
 157         unsigned long irqflags;
 158
 159         spin_lock_irqsave(&ntb->ctx_lock, irqflags);
 160         {
 161                 ntb->ctx_ops = NULL;
 162                 ntb->ctx = NULL;
 163         }
 164         spin_unlock_irqrestore(&ntb->ctx_lock, irqflags);
 165 }
 166 EXPORT_SYMBOL(ntb_clear_ctx);
 167
 168 void ntb_link_event(struct ntb_dev *ntb)
 169 {
 170         unsigned long irqflags;
 171
 172         spin_lock_irqsave(&ntb->ctx_lock, irqflags);
 173         {
 174                 if (ntb->ctx_ops && ntb->ctx_ops->link_event)
 175                         ntb->ctx_ops->link_event(ntb->ctx);
 176         }
 177         spin_unlock_irqrestore(&ntb->ctx_lock, irqflags);
 178 }
 179 EXPORT_SYMBOL(ntb_link_event);
 180
 181 void ntb_db_event(struct ntb_dev *ntb, int vector)
 182 {
 183         unsigned long irqflags;
 184
 185         spin_lock_irqsave(&ntb->ctx_lock, irqflags);
 186         {
 187                 if (ntb->ctx_ops && ntb->ctx_ops->db_event)
 188                         ntb->ctx_ops->db_event(ntb->ctx, vector);
 189         }
 190         spin_unlock_irqrestore(&ntb->ctx_lock, irqflags);
 191 }
 192 EXPORT_SYMBOL(ntb_db_event);
 193
 194 void ntb_msg_event(struct ntb_dev *ntb)
 195 {
 196         unsigned long irqflags;
 197
 198         spin_lock_irqsave(&ntb->ctx_lock, irqflags);
 199         {
 200                 if (ntb->ctx_ops && ntb->ctx_ops->msg_event)
 201                         ntb->ctx_ops->msg_event(ntb->ctx);
 202         }
 203         spin_unlock_irqrestore(&ntb->ctx_lock, irqflags);
 204 }
 205 EXPORT_SYMBOL(ntb_msg_event);
 206
 207 int ntb_default_port_number(struct ntb_dev *ntb)
 208 {
 209         switch (ntb->topo) {
 210         case NTB_TOPO_PRI:
 211         case NTB_TOPO_B2B_USD:
 212                 return NTB_PORT_PRI_USD;
 213         case NTB_TOPO_SEC:
 214         case NTB_TOPO_B2B_DSD:
 215                 return NTB_PORT_SEC_DSD;
 216         default:
 217                 break;
 218         }
 219
 220         return -EINVAL;
 221 }
 222 EXPORT_SYMBOL(ntb_default_port_number);
 223
 224 int ntb_default_peer_port_count(struct ntb_dev *ntb)
 225 {
 226         return NTB_DEF_PEER_CNT;
 227 }
 228 EXPORT_SYMBOL(ntb_default_peer_port_count);
 229
 230 int ntb_default_peer_port_number(struct ntb_dev *ntb, int pidx)
 231 {
 232         if (pidx != NTB_DEF_PEER_IDX)
 233                 return -EINVAL;
 234
 235         switch (ntb->topo) {
 236         case NTB_TOPO_PRI:
 237         case NTB_TOPO_B2B_USD:
 238                 return NTB_PORT_SEC_DSD;
 239         case NTB_TOPO_SEC:
 240         case NTB_TOPO_B2B_DSD:
 241                 return NTB_PORT_PRI_USD;
 242         default:
 243                 break;
 244         }
 245
 246         return -EINVAL;
 247 }
 248 EXPORT_SYMBOL(ntb_default_peer_port_number);
 249
 250 int ntb_default_peer_port_idx(struct ntb_dev *ntb, int port)
 251 {
 252         int peer_port = ntb_default_peer_port_number(ntb, NTB_DEF_PEER_IDX);
 253
 254         if (peer_port == -EINVAL || port != peer_port)
 255                 return -EINVAL;
 256
 257         return 0;
 258 }
 259 EXPORT_SYMBOL(ntb_default_peer_port_idx);
 260
 261 static int ntb_probe(struct device *dev)
 262 {
 263         struct ntb_dev *ntb;
 264         struct ntb_client *client;
 265         int rc;
 266
 267         get_device(dev);
 268         ntb = dev_ntb(dev);
 269         client = drv_ntb_client(dev->driver);
 270
 271         rc = client->ops.probe(client, ntb);
 272         if (rc)
 273                 put_device(dev);
 274
 275         return rc;
 276 }
 277
 278 static int ntb_remove(struct device *dev)
 279 {
 280         struct ntb_dev *ntb;
 281         struct ntb_client *client;
 282
 283         if (dev->driver) {
 284                 ntb = dev_ntb(dev);
 285                 client = drv_ntb_client(dev->driver);
 286
 287                 client->ops.remove(client, ntb);
 288                 put_device(dev);
 289         }
 290
 291         return 0;
 292 }
 293
 294 static void ntb_dev_release(struct device *dev)
 295 {
 296         struct ntb_dev *ntb = dev_ntb(dev);
 297
 298         complete(&ntb->released);
 299 }
 300
 301 static struct bus_type ntb_bus = {
 302         .name = "ntb",
 303         .probe = ntb_probe,
 304         .remove = ntb_remove,
 305 };
 306
 307 static int __init ntb_driver_init(void)
 308 {
 309         return bus_register(&ntb_bus);
 310 }
 311 module_init(ntb_driver_init);
 312
 313 static void __exit ntb_driver_exit(void)
 314 {
 315         bus_unregister(&ntb_bus);
 316 }
 317 module_exit(ntb_driver_exit);
 318