drivers/crypto/virtio/virtio_crypto_core.c

   1  /* Driver for Virtio crypto device.
   2   *
   3   * Copyright 2016 HUAWEI TECHNOLOGIES CO., LTD.
   4   *
   5   * This program is free software; you can redistribute it and/or modify
   6   * it under the terms of the GNU General Public License as published by
   7   * the Free Software Foundation; either version 2 of the License, or
   8   * (at your option) any later version.
   9   *
  10   * This program is distributed in the hope that it will be useful,
  11   * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13   * GNU General Public License for more details.
  14   *
  15   * You should have received a copy of the GNU General Public License
  16   * along with this program; if not, see <http://www.gnu.org/licenses/>.
  17   */
  18
  19 #include <linux/err.h>
  20 #include <linux/module.h>
  21 #include <linux/virtio_config.h>
  22 #include <linux/cpu.h>
  23
  24 #include <uapi/linux/virtio_crypto.h>
  25 #include "virtio_crypto_common.h"
  26
  27
  28 void
  29 virtcrypto_clear_request(struct virtio_crypto_request *vc_req)
  30 {
  31         if (vc_req) {
  32                 kzfree(vc_req->req_data);
  33                 kfree(vc_req->sgs);
  34         }
  35 }
  36
  37 static void virtcrypto_dataq_callback(struct virtqueue *vq)
  38 {
  39         struct virtio_crypto *vcrypto = vq->vdev->priv;
  40         struct virtio_crypto_request *vc_req;
  41         unsigned long flags;
  42         unsigned int len;
  43         unsigned int qid = vq->index;
  44
  45         spin_lock_irqsave(&vcrypto->data_vq[qid].lock, flags);
  46         do {
  47                 virtqueue_disable_cb(vq);
  48                 while ((vc_req = virtqueue_get_buf(vq, &len)) != NULL) {
  49                         spin_unlock_irqrestore(
  50                                 &vcrypto->data_vq[qid].lock, flags);
  51                         if (vc_req->alg_cb)
  52                                 vc_req->alg_cb(vc_req, len);
  53                         spin_lock_irqsave(
  54                                 &vcrypto->data_vq[qid].lock, flags);
  55                 }
  56         } while (!virtqueue_enable_cb(vq));
  57         spin_unlock_irqrestore(&vcrypto->data_vq[qid].lock, flags);
  58 }
  59
  60 static int virtcrypto_find_vqs(struct virtio_crypto *vi)
  61 {
  62         vq_callback_t **callbacks;
  63         struct virtqueue **vqs;
  64         int ret = -ENOMEM;
  65         int i, total_vqs;
  66         const char **names;
  67         struct device *dev = &vi->vdev->dev;
  68
  69         /*
  70          * We expect 1 data virtqueue, followed by
  71          * possible N-1 data queues used in multiqueue mode,
  72          * followed by control vq.
  73          */
  74         total_vqs = vi->max_data_queues + 1;
  75
  76         /* Allocate space for find_vqs parameters */
  77         vqs = kcalloc(total_vqs, sizeof(*vqs), GFP_KERNEL);
  78         if (!vqs)
  79                 goto err_vq;
  80         callbacks = kcalloc(total_vqs, sizeof(*callbacks), GFP_KERNEL);
  81         if (!callbacks)
  82                 goto err_callback;
  83         names = kcalloc(total_vqs, sizeof(*names), GFP_KERNEL);
  84         if (!names)
  85                 goto err_names;
  86
  87         /* Parameters for control virtqueue */
  88         callbacks[total_vqs - 1] = NULL;
  89         names[total_vqs - 1] = "controlq";
  90
  91         /* Allocate/initialize parameters for data virtqueues */
  92         for (i = 0; i < vi->max_data_queues; i++) {
  93                 callbacks[i] = virtcrypto_dataq_callback;
  94                 snprintf(vi->data_vq[i].name, sizeof(vi->data_vq[i].name),
  95                                 "dataq.%d", i);
  96                 names[i] = vi->data_vq[i].name;
  97         }
  98
  99         ret = virtio_find_vqs(vi->vdev, total_vqs, vqs, callbacks, names, NULL);
 100         if (ret)
 101                 goto err_find;
 102
 103         vi->ctrl_vq = vqs[total_vqs - 1];
 104
 105         for (i = 0; i < vi->max_data_queues; i++) {
 106                 spin_lock_init(&vi->data_vq[i].lock);
 107                 vi->data_vq[i].vq = vqs[i];
 108                 /* Initialize crypto engine */
 109                 vi->data_vq[i].engine = crypto_engine_alloc_init(dev, 1);
 110                 if (!vi->data_vq[i].engine) {
 111                         ret = -ENOMEM;
 112                         goto err_engine;
 113                 }
 114         }
 115
 116         kfree(names);
 117         kfree(callbacks);
 118         kfree(vqs);
 119
 120         return 0;
 121
 122 err_engine:
 123 err_find:
 124         kfree(names);
 125 err_names:
 126         kfree(callbacks);
 127 err_callback:
 128         kfree(vqs);
 129 err_vq:
 130         return ret;
 131 }
 132
 133 static int virtcrypto_alloc_queues(struct virtio_crypto *vi)
 134 {
 135         vi->data_vq = kcalloc(vi->max_data_queues, sizeof(*vi->data_vq),
 136                                 GFP_KERNEL);
 137         if (!vi->data_vq)
 138                 return -ENOMEM;
 139
 140         return 0;
 141 }
 142
 143 static void virtcrypto_clean_affinity(struct virtio_crypto *vi, long hcpu)
 144 {
 145         int i;
 146
 147         if (vi->affinity_hint_set) {
 148                 for (i = 0; i < vi->max_data_queues; i++)
 149                         virtqueue_set_affinity(vi->data_vq[i].vq, -1);
 150
 151                 vi->affinity_hint_set = false;
 152         }
 153 }
 154
 155 static void virtcrypto_set_affinity(struct virtio_crypto *vcrypto)
 156 {
 157         int i = 0;
 158         int cpu;
 159
 160         /*
 161          * In single queue mode, we don't set the cpu affinity.
 162          */
 163         if (vcrypto->curr_queue == 1 || vcrypto->max_data_queues == 1) {
 164                 virtcrypto_clean_affinity(vcrypto, -1);
 165                 return;
 166         }
 167
 168         /*
 169          * In multiqueue mode, we let the queue to be private to one cpu
 170          * by setting the affinity hint to eliminate the contention.
 171          *
 172          * TODO: adds cpu hotplug support by register cpu notifier.
 173          *
 174          */
 175         for_each_online_cpu(cpu) {
 176                 virtqueue_set_affinity(vcrypto->data_vq[i].vq, cpu);
 177                 if (++i >= vcrypto->max_data_queues)
 178                         break;
 179         }
 180
 181         vcrypto->affinity_hint_set = true;
 182 }
 183
 184 static void virtcrypto_free_queues(struct virtio_crypto *vi)
 185 {
 186         kfree(vi->data_vq);
 187 }
 188
 189 static int virtcrypto_init_vqs(struct virtio_crypto *vi)
 190 {
 191         int ret;
 192
 193         /* Allocate send & receive queues */
 194         ret = virtcrypto_alloc_queues(vi);
 195         if (ret)
 196                 goto err;
 197
 198         ret = virtcrypto_find_vqs(vi);
 199         if (ret)
 200                 goto err_free;
 201
 202         get_online_cpus();
 203         virtcrypto_set_affinity(vi);
 204         put_online_cpus();
 205
 206         return 0;
 207
 208 err_free:
 209         virtcrypto_free_queues(vi);
 210 err:
 211         return ret;
 212 }
 213
 214 static int virtcrypto_update_status(struct virtio_crypto *vcrypto)
 215 {
 216         u32 status;
 217         int err;
 218
 219         virtio_cread(vcrypto->vdev,
 220             struct virtio_crypto_config, status, &status);
 221
 222         /*
 223          * Unknown status bits would be a host error and the driver
 224          * should consider the device to be broken.
 225          */
 226         if (status & (~VIRTIO_CRYPTO_S_HW_READY)) {
 227                 dev_warn(&vcrypto->vdev->dev,
 228                                 "Unknown status bits: 0x%x\n", status);
 229
 230                 virtio_break_device(vcrypto->vdev);
 231                 return -EPERM;
 232         }
 233
 234         if (vcrypto->status == status)
 235                 return 0;
 236
 237         vcrypto->status = status;
 238
 239         if (vcrypto->status & VIRTIO_CRYPTO_S_HW_READY) {
 240                 err = virtcrypto_dev_start(vcrypto);
 241                 if (err) {
 242                         dev_err(&vcrypto->vdev->dev,
 243                                 "Failed to start virtio crypto device.\n");
 244
 245                         return -EPERM;
 246                 }
 247                 dev_info(&vcrypto->vdev->dev, "Accelerator device is ready\n");
 248         } else {
 249                 virtcrypto_dev_stop(vcrypto);
 250                 dev_info(&vcrypto->vdev->dev, "Accelerator is not ready\n");
 251         }
 252
 253         return 0;
 254 }
 255
 256 static int virtcrypto_start_crypto_engines(struct virtio_crypto *vcrypto)
 257 {
 258         int32_t i;
 259         int ret;
 260
 261         for (i = 0; i < vcrypto->max_data_queues; i++) {
 262                 if (vcrypto->data_vq[i].engine) {
 263                         ret = crypto_engine_start(vcrypto->data_vq[i].engine);
 264                         if (ret)
 265                                 goto err;
 266                 }
 267         }
 268
 269         return 0;
 270
 271 err:
 272         while (--i >= 0)
 273                 if (vcrypto->data_vq[i].engine)
 274                         crypto_engine_exit(vcrypto->data_vq[i].engine);
 275
 276         return ret;
 277 }
 278
 279 static void virtcrypto_clear_crypto_engines(struct virtio_crypto *vcrypto)
 280 {
 281         u32 i;
 282
 283         for (i = 0; i < vcrypto->max_data_queues; i++)
 284                 if (vcrypto->data_vq[i].engine)
 285                         crypto_engine_exit(vcrypto->data_vq[i].engine);
 286 }
 287
 288 static void virtcrypto_del_vqs(struct virtio_crypto *vcrypto)
 289 {
 290         struct virtio_device *vdev = vcrypto->vdev;
 291
 292         virtcrypto_clean_affinity(vcrypto, -1);
 293
 294         vdev->config->del_vqs(vdev);
 295
 296         virtcrypto_free_queues(vcrypto);
 297 }
 298
 299 static int virtcrypto_probe(struct virtio_device *vdev)
 300 {
 301         int err = -EFAULT;
 302         struct virtio_crypto *vcrypto;
 303         u32 max_data_queues = 0, max_cipher_key_len = 0;
 304         u32 max_auth_key_len = 0;
 305         u64 max_size = 0;
 306
 307         if (!virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
 308                 return -ENODEV;
 309
 310         if (!vdev->config->get) {
 311                 dev_err(&vdev->dev, "%s failure: config access disabled\n",
 312                         __func__);
 313                 return -EINVAL;
 314         }
 315
 316         if (num_possible_nodes() > 1 && dev_to_node(&vdev->dev) < 0) {
 317                 /*
 318                  * If the accelerator is connected to a node with no memory
 319                  * there is no point in using the accelerator since the remote
 320                  * memory transaction will be very slow.
 321                  */
 322                 dev_err(&vdev->dev, "Invalid NUMA configuration.\n");
 323                 return -EINVAL;
 324         }
 325
 326         vcrypto = kzalloc_node(sizeof(*vcrypto), GFP_KERNEL,
 327                                         dev_to_node(&vdev->dev));
 328         if (!vcrypto)
 329                 return -ENOMEM;
 330
 331         virtio_cread(vdev, struct virtio_crypto_config,
 332                         max_dataqueues, &max_data_queues);
 333         if (max_data_queues < 1)
 334                 max_data_queues = 1;
 335
 336         virtio_cread(vdev, struct virtio_crypto_config,
 337                 max_cipher_key_len, &max_cipher_key_len);
 338         virtio_cread(vdev, struct virtio_crypto_config,
 339                 max_auth_key_len, &max_auth_key_len);
 340         virtio_cread(vdev, struct virtio_crypto_config,
 341                 max_size, &max_size);
 342
 343         /* Add virtio crypto device to global table */
 344         err = virtcrypto_devmgr_add_dev(vcrypto);
 345         if (err) {
 346                 dev_err(&vdev->dev, "Failed to add new virtio crypto device.\n");
 347                 goto free;
 348         }
 349         vcrypto->owner = THIS_MODULE;
 350         vcrypto = vdev->priv = vcrypto;
 351         vcrypto->vdev = vdev;
 352
 353         spin_lock_init(&vcrypto->ctrl_lock);
 354
 355         /* Use single data queue as default */
 356         vcrypto->curr_queue = 1;
 357         vcrypto->max_data_queues = max_data_queues;
 358         vcrypto->max_cipher_key_len = max_cipher_key_len;
 359         vcrypto->max_auth_key_len = max_auth_key_len;
 360         vcrypto->max_size = max_size;
 361
 362         dev_info(&vdev->dev,
 363                 "max_queues: %u, max_cipher_key_len: %u, max_auth_key_len: %u, max_size 0x%llx\n",
 364                 vcrypto->max_data_queues,
 365                 vcrypto->max_cipher_key_len,
 366                 vcrypto->max_auth_key_len,
 367                 vcrypto->max_size);
 368
 369         err = virtcrypto_init_vqs(vcrypto);
 370         if (err) {
 371                 dev_err(&vdev->dev, "Failed to initialize vqs.\n");
 372                 goto free_dev;
 373         }
 374
 375         err = virtcrypto_start_crypto_engines(vcrypto);
 376         if (err)
 377                 goto free_vqs;
 378
 379         virtio_device_ready(vdev);
 380
 381         err = virtcrypto_update_status(vcrypto);
 382         if (err)
 383                 goto free_engines;
 384
 385         return 0;
 386
 387 free_engines:
 388         virtcrypto_clear_crypto_engines(vcrypto);
 389 free_vqs:
 390         vcrypto->vdev->config->reset(vdev);
 391         virtcrypto_del_vqs(vcrypto);
 392 free_dev:
 393         virtcrypto_devmgr_rm_dev(vcrypto);
 394 free:
 395         kfree(vcrypto);
 396         return err;
 397 }
 398
 399 static void virtcrypto_free_unused_reqs(struct virtio_crypto *vcrypto)
 400 {
 401         struct virtio_crypto_request *vc_req;
 402         int i;
 403         struct virtqueue *vq;
 404
 405         for (i = 0; i < vcrypto->max_data_queues; i++) {
 406                 vq = vcrypto->data_vq[i].vq;
 407                 while ((vc_req = virtqueue_detach_unused_buf(vq)) != NULL) {
 408                         kfree(vc_req->req_data);
 409                         kfree(vc_req->sgs);
 410                 }
 411         }
 412 }
 413
 414 static void virtcrypto_remove(struct virtio_device *vdev)
 415 {
 416         struct virtio_crypto *vcrypto = vdev->priv;
 417
 418         dev_info(&vdev->dev, "Start virtcrypto_remove.\n");
 419
 420         if (virtcrypto_dev_started(vcrypto))
 421                 virtcrypto_dev_stop(vcrypto);
 422         vdev->config->reset(vdev);
 423         virtcrypto_free_unused_reqs(vcrypto);
 424         virtcrypto_clear_crypto_engines(vcrypto);
 425         virtcrypto_del_vqs(vcrypto);
 426         virtcrypto_devmgr_rm_dev(vcrypto);
 427         kfree(vcrypto);
 428 }
 429
 430 static void virtcrypto_config_changed(struct virtio_device *vdev)
 431 {
 432         struct virtio_crypto *vcrypto = vdev->priv;
 433
 434         virtcrypto_update_status(vcrypto);
 435 }
 436
 437 #ifdef CONFIG_PM_SLEEP
 438 static int virtcrypto_freeze(struct virtio_device *vdev)
 439 {
 440         struct virtio_crypto *vcrypto = vdev->priv;
 441
 442         vdev->config->reset(vdev);
 443         virtcrypto_free_unused_reqs(vcrypto);
 444         if (virtcrypto_dev_started(vcrypto))
 445                 virtcrypto_dev_stop(vcrypto);
 446
 447         virtcrypto_clear_crypto_engines(vcrypto);
 448         virtcrypto_del_vqs(vcrypto);
 449         return 0;
 450 }
 451
 452 static int virtcrypto_restore(struct virtio_device *vdev)
 453 {
 454         struct virtio_crypto *vcrypto = vdev->priv;
 455         int err;
 456
 457         err = virtcrypto_init_vqs(vcrypto);
 458         if (err)
 459                 return err;
 460
 461         err = virtcrypto_start_crypto_engines(vcrypto);
 462         if (err)
 463                 goto free_vqs;
 464
 465         virtio_device_ready(vdev);
 466
 467         err = virtcrypto_dev_start(vcrypto);
 468         if (err) {
 469                 dev_err(&vdev->dev, "Failed to start virtio crypto device.\n");
 470                 goto free_engines;
 471         }
 472
 473         return 0;
 474
 475 free_engines:
 476         virtcrypto_clear_crypto_engines(vcrypto);
 477 free_vqs:
 478         vcrypto->vdev->config->reset(vdev);
 479         virtcrypto_del_vqs(vcrypto);
 480         return err;
 481 }
 482 #endif
 483
 484 static unsigned int features[] = {
 485         /* none */
 486 };
 487
 488 static struct virtio_device_id id_table[] = {
 489         { VIRTIO_ID_CRYPTO, VIRTIO_DEV_ANY_ID },
 490         { 0 },
 491 };
 492
 493 static struct virtio_driver virtio_crypto_driver = {
 494         .driver.name         = KBUILD_MODNAME,
 495         .driver.owner        = THIS_MODULE,
 496         .feature_table       = features,
 497         .feature_table_size  = ARRAY_SIZE(features),
 498         .id_table            = id_table,
 499         .probe               = virtcrypto_probe,
 500         .remove              = virtcrypto_remove,
 501         .config_changed = virtcrypto_config_changed,
 502 #ifdef CONFIG_PM_SLEEP
 503         .freeze = virtcrypto_freeze,
 504         .restore = virtcrypto_restore,
 505 #endif
 506 };
 507
 508 module_virtio_driver(virtio_crypto_driver);
 509
 510 MODULE_DEVICE_TABLE(virtio, id_table);
 511 MODULE_DESCRIPTION("virtio crypto device driver");
 512 MODULE_LICENSE("GPL");
 513 MODULE_AUTHOR("Gonglei <arei.gonglei@huawei.com>");