drivers/vdpa/alibaba/eni_vdpa.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * vDPA bridge driver for Alibaba ENI(Elastic Network Interface)
   4  *
   5  * Copyright (c) 2021, Alibaba Inc. All rights reserved.
   6  * Author: Wu Zongyong <wuzongyong@linux.alibaba.com>
   7  *
   8  */
   9
  10 #include "linux/bits.h"
  11 #include <linux/interrupt.h>
  12 #include <linux/module.h>
  13 #include <linux/pci.h>
  14 #include <linux/vdpa.h>
  15 #include <linux/virtio.h>
  16 #include <linux/virtio_config.h>
  17 #include <linux/virtio_ring.h>
  18 #include <linux/virtio_pci.h>
  19 #include <linux/virtio_pci_legacy.h>
  20 #include <uapi/linux/virtio_net.h>
  21
  22 #define ENI_MSIX_NAME_SIZE 256
  23
  24 #define ENI_ERR(pdev, fmt, ...) \
  25         dev_err(&pdev->dev, "%s"fmt, "eni_vdpa: ", ##__VA_ARGS__)
  26 #define ENI_DBG(pdev, fmt, ...) \
  27         dev_dbg(&pdev->dev, "%s"fmt, "eni_vdpa: ", ##__VA_ARGS__)
  28 #define ENI_INFO(pdev, fmt, ...) \
  29         dev_info(&pdev->dev, "%s"fmt, "eni_vdpa: ", ##__VA_ARGS__)
  30
  31 struct eni_vring {
  32         void __iomem *notify;
  33         char msix_name[ENI_MSIX_NAME_SIZE];
  34         struct vdpa_callback cb;
  35         int irq;
  36 };
  37
  38 struct eni_vdpa {
  39         struct vdpa_device vdpa;
  40         struct virtio_pci_legacy_device ldev;
  41         struct eni_vring *vring;
  42         struct vdpa_callback config_cb;
  43         char msix_name[ENI_MSIX_NAME_SIZE];
  44         int config_irq;
  45         int queues;
  46         int vectors;
  47 };
  48
  49 static struct eni_vdpa *vdpa_to_eni(struct vdpa_device *vdpa)
  50 {
  51         return container_of(vdpa, struct eni_vdpa, vdpa);
  52 }
  53
  54 static struct virtio_pci_legacy_device *vdpa_to_ldev(struct vdpa_device *vdpa)
  55 {
  56         struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
  57
  58         return &eni_vdpa->ldev;
  59 }
  60
  61 static u64 eni_vdpa_get_device_features(struct vdpa_device *vdpa)
  62 {
  63         struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
  64         u64 features = vp_legacy_get_features(ldev);
  65
  66         features |= BIT_ULL(VIRTIO_F_ACCESS_PLATFORM);
  67         features |= BIT_ULL(VIRTIO_F_ORDER_PLATFORM);
  68
  69         return features;
  70 }
  71
  72 static int eni_vdpa_set_driver_features(struct vdpa_device *vdpa, u64 features)
  73 {
  74         struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
  75
  76         if (!(features & BIT_ULL(VIRTIO_NET_F_MRG_RXBUF)) && features) {
  77                 ENI_ERR(ldev->pci_dev,
  78                         "VIRTIO_NET_F_MRG_RXBUF is not negotiated\n");
  79                 return -EINVAL;
  80         }
  81
  82         vp_legacy_set_features(ldev, (u32)features);
  83
  84         return 0;
  85 }
  86
  87 static u64 eni_vdpa_get_driver_features(struct vdpa_device *vdpa)
  88 {
  89         struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
  90
  91         return vp_legacy_get_driver_features(ldev);
  92 }
  93
  94 static u8 eni_vdpa_get_status(struct vdpa_device *vdpa)
  95 {
  96         struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
  97
  98         return vp_legacy_get_status(ldev);
  99 }
 100
 101 static int eni_vdpa_get_vq_irq(struct vdpa_device *vdpa, u16 idx)
 102 {
 103         struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
 104         int irq = eni_vdpa->vring[idx].irq;
 105
 106         if (irq == VIRTIO_MSI_NO_VECTOR)
 107                 return -EINVAL;
 108
 109         return irq;
 110 }
 111
 112 static void eni_vdpa_free_irq(struct eni_vdpa *eni_vdpa)
 113 {
 114         struct virtio_pci_legacy_device *ldev = &eni_vdpa->ldev;
 115         struct pci_dev *pdev = ldev->pci_dev;
 116         int i;
 117
 118         for (i = 0; i < eni_vdpa->queues; i++) {
 119                 if (eni_vdpa->vring[i].irq != VIRTIO_MSI_NO_VECTOR) {
 120                         vp_legacy_queue_vector(ldev, i, VIRTIO_MSI_NO_VECTOR);
 121                         devm_free_irq(&pdev->dev, eni_vdpa->vring[i].irq,
 122                                       &eni_vdpa->vring[i]);
 123                         eni_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
 124                 }
 125         }
 126
 127         if (eni_vdpa->config_irq != VIRTIO_MSI_NO_VECTOR) {
 128                 vp_legacy_config_vector(ldev, VIRTIO_MSI_NO_VECTOR);
 129                 devm_free_irq(&pdev->dev, eni_vdpa->config_irq, eni_vdpa);
 130                 eni_vdpa->config_irq = VIRTIO_MSI_NO_VECTOR;
 131         }
 132
 133         if (eni_vdpa->vectors) {
 134                 pci_free_irq_vectors(pdev);
 135                 eni_vdpa->vectors = 0;
 136         }
 137 }
 138
 139 static irqreturn_t eni_vdpa_vq_handler(int irq, void *arg)
 140 {
 141         struct eni_vring *vring = arg;
 142
 143         if (vring->cb.callback)
 144                 return vring->cb.callback(vring->cb.private);
 145
 146         return IRQ_HANDLED;
 147 }
 148
 149 static irqreturn_t eni_vdpa_config_handler(int irq, void *arg)
 150 {
 151         struct eni_vdpa *eni_vdpa = arg;
 152
 153         if (eni_vdpa->config_cb.callback)
 154                 return eni_vdpa->config_cb.callback(eni_vdpa->config_cb.private);
 155
 156         return IRQ_HANDLED;
 157 }
 158
 159 static int eni_vdpa_request_irq(struct eni_vdpa *eni_vdpa)
 160 {
 161         struct virtio_pci_legacy_device *ldev = &eni_vdpa->ldev;
 162         struct pci_dev *pdev = ldev->pci_dev;
 163         int i, ret, irq;
 164         int queues = eni_vdpa->queues;
 165         int vectors = queues + 1;
 166
 167         ret = pci_alloc_irq_vectors(pdev, vectors, vectors, PCI_IRQ_MSIX);
 168         if (ret != vectors) {
 169                 ENI_ERR(pdev,
 170                         "failed to allocate irq vectors want %d but %d\n",
 171                         vectors, ret);
 172                 return ret;
 173         }
 174
 175         eni_vdpa->vectors = vectors;
 176
 177         for (i = 0; i < queues; i++) {
 178                 snprintf(eni_vdpa->vring[i].msix_name, ENI_MSIX_NAME_SIZE,
 179                          "eni-vdpa[%s]-%d\n", pci_name(pdev), i);
 180                 irq = pci_irq_vector(pdev, i);
 181                 ret = devm_request_irq(&pdev->dev, irq,
 182                                        eni_vdpa_vq_handler,
 183                                        0, eni_vdpa->vring[i].msix_name,
 184                                        &eni_vdpa->vring[i]);
 185                 if (ret) {
 186                         ENI_ERR(pdev, "failed to request irq for vq %d\n", i);
 187                         goto err;
 188                 }
 189                 vp_legacy_queue_vector(ldev, i, i);
 190                 eni_vdpa->vring[i].irq = irq;
 191         }
 192
 193         snprintf(eni_vdpa->msix_name, ENI_MSIX_NAME_SIZE, "eni-vdpa[%s]-config\n",
 194                  pci_name(pdev));
 195         irq = pci_irq_vector(pdev, queues);
 196         ret = devm_request_irq(&pdev->dev, irq, eni_vdpa_config_handler, 0,
 197                                eni_vdpa->msix_name, eni_vdpa);
 198         if (ret) {
 199                 ENI_ERR(pdev, "failed to request irq for config vq %d\n", i);
 200                 goto err;
 201         }
 202         vp_legacy_config_vector(ldev, queues);
 203         eni_vdpa->config_irq = irq;
 204
 205         return 0;
 206 err:
 207         eni_vdpa_free_irq(eni_vdpa);
 208         return ret;
 209 }
 210
 211 static void eni_vdpa_set_status(struct vdpa_device *vdpa, u8 status)
 212 {
 213         struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
 214         struct virtio_pci_legacy_device *ldev = &eni_vdpa->ldev;
 215         u8 s = eni_vdpa_get_status(vdpa);
 216
 217         if (status & VIRTIO_CONFIG_S_DRIVER_OK &&
 218             !(s & VIRTIO_CONFIG_S_DRIVER_OK)) {
 219                 eni_vdpa_request_irq(eni_vdpa);
 220         }
 221
 222         vp_legacy_set_status(ldev, status);
 223
 224         if (!(status & VIRTIO_CONFIG_S_DRIVER_OK) &&
 225             (s & VIRTIO_CONFIG_S_DRIVER_OK))
 226                 eni_vdpa_free_irq(eni_vdpa);
 227 }
 228
 229 static int eni_vdpa_reset(struct vdpa_device *vdpa)
 230 {
 231         struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
 232         struct virtio_pci_legacy_device *ldev = &eni_vdpa->ldev;
 233         u8 s = eni_vdpa_get_status(vdpa);
 234
 235         vp_legacy_set_status(ldev, 0);
 236
 237         if (s & VIRTIO_CONFIG_S_DRIVER_OK)
 238                 eni_vdpa_free_irq(eni_vdpa);
 239
 240         return 0;
 241 }
 242
 243 static u16 eni_vdpa_get_vq_num_max(struct vdpa_device *vdpa)
 244 {
 245         struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
 246
 247         return vp_legacy_get_queue_size(ldev, 0);
 248 }
 249
 250 static u16 eni_vdpa_get_vq_num_min(struct vdpa_device *vdpa)
 251 {
 252         struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
 253
 254         return vp_legacy_get_queue_size(ldev, 0);
 255 }
 256
 257 static u16 eni_vdpa_get_vq_size(struct vdpa_device *vdpa, u16 qid)
 258 {
 259         struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
 260
 261         return vp_legacy_get_queue_size(ldev, qid);
 262 }
 263
 264 static int eni_vdpa_get_vq_state(struct vdpa_device *vdpa, u16 qid,
 265                                 struct vdpa_vq_state *state)
 266 {
 267         return -EOPNOTSUPP;
 268 }
 269
 270 static int eni_vdpa_set_vq_state(struct vdpa_device *vdpa, u16 qid,
 271                                  const struct vdpa_vq_state *state)
 272 {
 273         struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
 274         const struct vdpa_vq_state_split *split = &state->split;
 275
 276         /* ENI is build upon virtio-pci specfication which not support
 277          * to set state of virtqueue. But if the state is equal to the
 278          * device initial state by chance, we can let it go.
 279          */
 280         if (!vp_legacy_get_queue_enable(ldev, qid)
 281             && split->avail_index == 0)
 282                 return 0;
 283
 284         return -EOPNOTSUPP;
 285 }
 286
 287
 288 static void eni_vdpa_set_vq_cb(struct vdpa_device *vdpa, u16 qid,
 289                                struct vdpa_callback *cb)
 290 {
 291         struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
 292
 293         eni_vdpa->vring[qid].cb = *cb;
 294 }
 295
 296 static void eni_vdpa_set_vq_ready(struct vdpa_device *vdpa, u16 qid,
 297                                   bool ready)
 298 {
 299         struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
 300
 301         /* ENI is a legacy virtio-pci device. This is not supported
 302          * by specification. But we can disable virtqueue by setting
 303          * address to 0.
 304          */
 305         if (!ready)
 306                 vp_legacy_set_queue_address(ldev, qid, 0);
 307 }
 308
 309 static bool eni_vdpa_get_vq_ready(struct vdpa_device *vdpa, u16 qid)
 310 {
 311         struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
 312
 313         return vp_legacy_get_queue_enable(ldev, qid);
 314 }
 315
 316 static void eni_vdpa_set_vq_num(struct vdpa_device *vdpa, u16 qid,
 317                                u32 num)
 318 {
 319         struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
 320         struct pci_dev *pdev = ldev->pci_dev;
 321         u16 n = vp_legacy_get_queue_size(ldev, qid);
 322
 323         /* ENI is a legacy virtio-pci device which not allow to change
 324          * virtqueue size. Just report a error if someone tries to
 325          * change it.
 326          */
 327         if (num != n)
 328                 ENI_ERR(pdev,
 329                         "not support to set vq %u fixed num %u to %u\n",
 330                         qid, n, num);
 331 }
 332
 333 static int eni_vdpa_set_vq_address(struct vdpa_device *vdpa, u16 qid,
 334                                    u64 desc_area, u64 driver_area,
 335                                    u64 device_area)
 336 {
 337         struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
 338         u32 pfn = desc_area >> VIRTIO_PCI_QUEUE_ADDR_SHIFT;
 339
 340         vp_legacy_set_queue_address(ldev, qid, pfn);
 341
 342         return 0;
 343 }
 344
 345 static void eni_vdpa_kick_vq(struct vdpa_device *vdpa, u16 qid)
 346 {
 347         struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
 348
 349         iowrite16(qid, eni_vdpa->vring[qid].notify);
 350 }
 351
 352 static u32 eni_vdpa_get_device_id(struct vdpa_device *vdpa)
 353 {
 354         struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
 355
 356         return ldev->id.device;
 357 }
 358
 359 static u32 eni_vdpa_get_vendor_id(struct vdpa_device *vdpa)
 360 {
 361         struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
 362
 363         return ldev->id.vendor;
 364 }
 365
 366 static u32 eni_vdpa_get_vq_align(struct vdpa_device *vdpa)
 367 {
 368         return VIRTIO_PCI_VRING_ALIGN;
 369 }
 370
 371 static size_t eni_vdpa_get_config_size(struct vdpa_device *vdpa)
 372 {
 373         return sizeof(struct virtio_net_config);
 374 }
 375
 376
 377 static void eni_vdpa_get_config(struct vdpa_device *vdpa,
 378                                 unsigned int offset,
 379                                 void *buf, unsigned int len)
 380 {
 381         struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
 382         struct virtio_pci_legacy_device *ldev = &eni_vdpa->ldev;
 383         void __iomem *ioaddr = ldev->ioaddr +
 384                 VIRTIO_PCI_CONFIG_OFF(eni_vdpa->vectors) +
 385                 offset;
 386         u8 *p = buf;
 387         int i;
 388
 389         for (i = 0; i < len; i++)
 390                 *p++ = ioread8(ioaddr + i);
 391 }
 392
 393 static void eni_vdpa_set_config(struct vdpa_device *vdpa,
 394                                 unsigned int offset, const void *buf,
 395                                 unsigned int len)
 396 {
 397         struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
 398         struct virtio_pci_legacy_device *ldev = &eni_vdpa->ldev;
 399         void __iomem *ioaddr = ldev->ioaddr +
 400                 VIRTIO_PCI_CONFIG_OFF(eni_vdpa->vectors) +
 401                 offset;
 402         const u8 *p = buf;
 403         int i;
 404
 405         for (i = 0; i < len; i++)
 406                 iowrite8(*p++, ioaddr + i);
 407 }
 408
 409 static void eni_vdpa_set_config_cb(struct vdpa_device *vdpa,
 410                                    struct vdpa_callback *cb)
 411 {
 412         struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
 413
 414         eni_vdpa->config_cb = *cb;
 415 }
 416
 417 static const struct vdpa_config_ops eni_vdpa_ops = {
 418         .get_device_features = eni_vdpa_get_device_features,
 419         .set_driver_features = eni_vdpa_set_driver_features,
 420         .get_driver_features = eni_vdpa_get_driver_features,
 421         .get_status     = eni_vdpa_get_status,
 422         .set_status     = eni_vdpa_set_status,
 423         .reset          = eni_vdpa_reset,
 424         .get_vq_num_max = eni_vdpa_get_vq_num_max,
 425         .get_vq_num_min = eni_vdpa_get_vq_num_min,
 426         .get_vq_size    = eni_vdpa_get_vq_size,
 427         .get_vq_state   = eni_vdpa_get_vq_state,
 428         .set_vq_state   = eni_vdpa_set_vq_state,
 429         .set_vq_cb      = eni_vdpa_set_vq_cb,
 430         .set_vq_ready   = eni_vdpa_set_vq_ready,
 431         .get_vq_ready   = eni_vdpa_get_vq_ready,
 432         .set_vq_num     = eni_vdpa_set_vq_num,
 433         .set_vq_address = eni_vdpa_set_vq_address,
 434         .kick_vq        = eni_vdpa_kick_vq,
 435         .get_device_id  = eni_vdpa_get_device_id,
 436         .get_vendor_id  = eni_vdpa_get_vendor_id,
 437         .get_vq_align   = eni_vdpa_get_vq_align,
 438         .get_config_size = eni_vdpa_get_config_size,
 439         .get_config     = eni_vdpa_get_config,
 440         .set_config     = eni_vdpa_set_config,
 441         .set_config_cb  = eni_vdpa_set_config_cb,
 442         .get_vq_irq     = eni_vdpa_get_vq_irq,
 443 };
 444
 445
 446 static u16 eni_vdpa_get_num_queues(struct eni_vdpa *eni_vdpa)
 447 {
 448         struct virtio_pci_legacy_device *ldev = &eni_vdpa->ldev;
 449         u32 features = vp_legacy_get_features(ldev);
 450         u16 num = 2;
 451
 452         if (features & BIT_ULL(VIRTIO_NET_F_MQ)) {
 453                 __virtio16 max_virtqueue_pairs;
 454
 455                 eni_vdpa_get_config(&eni_vdpa->vdpa,
 456                         offsetof(struct virtio_net_config, max_virtqueue_pairs),
 457                         &max_virtqueue_pairs,
 458                         sizeof(max_virtqueue_pairs));
 459                 num = 2 * __virtio16_to_cpu(virtio_legacy_is_little_endian(),
 460                                 max_virtqueue_pairs);
 461         }
 462
 463         if (features & BIT_ULL(VIRTIO_NET_F_CTRL_VQ))
 464                 num += 1;
 465
 466         return num;
 467 }
 468
 469 static int eni_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 470 {
 471         struct device *dev = &pdev->dev;
 472         struct eni_vdpa *eni_vdpa;
 473         struct virtio_pci_legacy_device *ldev;
 474         int ret, i;
 475
 476         ret = pcim_enable_device(pdev);
 477         if (ret)
 478                 return ret;
 479
 480         eni_vdpa = vdpa_alloc_device(struct eni_vdpa, vdpa,
 481                                      dev, &eni_vdpa_ops, 1, 1, NULL, false);
 482         if (IS_ERR(eni_vdpa)) {
 483                 ENI_ERR(pdev, "failed to allocate vDPA structure\n");
 484                 return PTR_ERR(eni_vdpa);
 485         }
 486
 487         ldev = &eni_vdpa->ldev;
 488         ldev->pci_dev = pdev;
 489
 490         ret = vp_legacy_probe(ldev);
 491         if (ret) {
 492                 ENI_ERR(pdev, "failed to probe legacy PCI device\n");
 493                 goto err;
 494         }
 495
 496         pci_set_master(pdev);
 497         pci_set_drvdata(pdev, eni_vdpa);
 498
 499         eni_vdpa->vdpa.dma_dev = &pdev->dev;
 500         eni_vdpa->queues = eni_vdpa_get_num_queues(eni_vdpa);
 501
 502         eni_vdpa->vring = devm_kcalloc(&pdev->dev, eni_vdpa->queues,
 503                                       sizeof(*eni_vdpa->vring),
 504                                       GFP_KERNEL);
 505         if (!eni_vdpa->vring) {
 506                 ret = -ENOMEM;
 507                 ENI_ERR(pdev, "failed to allocate virtqueues\n");
 508                 goto err_remove_vp_legacy;
 509         }
 510
 511         for (i = 0; i < eni_vdpa->queues; i++) {
 512                 eni_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
 513                 eni_vdpa->vring[i].notify = ldev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY;
 514         }
 515         eni_vdpa->config_irq = VIRTIO_MSI_NO_VECTOR;
 516
 517         ret = vdpa_register_device(&eni_vdpa->vdpa, eni_vdpa->queues);
 518         if (ret) {
 519                 ENI_ERR(pdev, "failed to register to vdpa bus\n");
 520                 goto err_remove_vp_legacy;
 521         }
 522
 523         return 0;
 524
 525 err_remove_vp_legacy:
 526         vp_legacy_remove(&eni_vdpa->ldev);
 527 err:
 528         put_device(&eni_vdpa->vdpa.dev);
 529         return ret;
 530 }
 531
 532 static void eni_vdpa_remove(struct pci_dev *pdev)
 533 {
 534         struct eni_vdpa *eni_vdpa = pci_get_drvdata(pdev);
 535
 536         vdpa_unregister_device(&eni_vdpa->vdpa);
 537         vp_legacy_remove(&eni_vdpa->ldev);
 538 }
 539
 540 static struct pci_device_id eni_pci_ids[] = {
 541         { PCI_DEVICE_SUB(PCI_VENDOR_ID_REDHAT_QUMRANET,
 542                          VIRTIO_TRANS_ID_NET,
 543                          PCI_SUBVENDOR_ID_REDHAT_QUMRANET,
 544                          VIRTIO_ID_NET) },
 545         { 0 },
 546 };
 547
 548 static struct pci_driver eni_vdpa_driver = {
 549         .name           = "alibaba-eni-vdpa",
 550         .id_table       = eni_pci_ids,
 551         .probe          = eni_vdpa_probe,
 552         .remove         = eni_vdpa_remove,
 553 };
 554
 555 module_pci_driver(eni_vdpa_driver);
 556
 557 MODULE_AUTHOR("Wu Zongyong <wuzongyong@linux.alibaba.com>");
 558 MODULE_DESCRIPTION("Alibaba ENI vDPA driver");
 559 MODULE_LICENSE("GPL v2");