drivers/virtio/virtio_pci_modern_dev.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2
   3 #include <linux/virtio_pci_modern.h>
   4 #include <linux/module.h>
   5 #include <linux/pci.h>
   6 #include <linux/delay.h>
   7
   8 /*
   9  * vp_modern_map_capability - map a part of virtio pci capability
  10  * @mdev: the modern virtio-pci device
  11  * @off: offset of the capability
  12  * @minlen: minimal length of the capability
  13  * @align: align requirement
  14  * @start: start from the capability
  15  * @size: map size
  16  * @len: the length that is actually mapped
  17  * @pa: physical address of the capability
  18  *
  19  * Returns the io address of for the part of the capability
  20  */
  21 static void __iomem *
  22 vp_modern_map_capability(struct virtio_pci_modern_device *mdev, int off,
  23                          size_t minlen, u32 align, u32 start, u32 size,
  24                          size_t *len, resource_size_t *pa)
  25 {
  26         struct pci_dev *dev = mdev->pci_dev;
  27         u8 bar;
  28         u32 offset, length;
  29         void __iomem *p;
  30
  31         pci_read_config_byte(dev, off + offsetof(struct virtio_pci_cap,
  32                                                  bar),
  33                              &bar);
  34         pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, offset),
  35                              &offset);
  36         pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, length),
  37                               &length);
  38
  39         /* Check if the BAR may have changed since we requested the region. */
  40         if (bar >= PCI_STD_NUM_BARS || !(mdev->modern_bars & (1 << bar))) {
  41                 dev_err(&dev->dev,
  42                         "virtio_pci: bar unexpectedly changed to %u\n", bar);
  43                 return NULL;
  44         }
  45
  46         if (length <= start) {
  47                 dev_err(&dev->dev,
  48                         "virtio_pci: bad capability len %u (>%u expected)\n",
  49                         length, start);
  50                 return NULL;
  51         }
  52
  53         if (length - start < minlen) {
  54                 dev_err(&dev->dev,
  55                         "virtio_pci: bad capability len %u (>=%zu expected)\n",
  56                         length, minlen);
  57                 return NULL;
  58         }
  59
  60         length -= start;
  61
  62         if (start + offset < offset) {
  63                 dev_err(&dev->dev,
  64                         "virtio_pci: map wrap-around %u+%u\n",
  65                         start, offset);
  66                 return NULL;
  67         }
  68
  69         offset += start;
  70
  71         if (offset & (align - 1)) {
  72                 dev_err(&dev->dev,
  73                         "virtio_pci: offset %u not aligned to %u\n",
  74                         offset, align);
  75                 return NULL;
  76         }
  77
  78         if (length > size)
  79                 length = size;
  80
  81         if (len)
  82                 *len = length;
  83
  84         if (minlen + offset < minlen ||
  85             minlen + offset > pci_resource_len(dev, bar)) {
  86                 dev_err(&dev->dev,
  87                         "virtio_pci: map virtio %zu@%u "
  88                         "out of range on bar %i length %lu\n",
  89                         minlen, offset,
  90                         bar, (unsigned long)pci_resource_len(dev, bar));
  91                 return NULL;
  92         }
  93
  94         p = pci_iomap_range(dev, bar, offset, length);
  95         if (!p)
  96                 dev_err(&dev->dev,
  97                         "virtio_pci: unable to map virtio %u@%u on bar %i\n",
  98                         length, offset, bar);
  99         else if (pa)
 100                 *pa = pci_resource_start(dev, bar) + offset;
 101
 102         return p;
 103 }
 104
 105 /**
 106  * virtio_pci_find_capability - walk capabilities to find device info.
 107  * @dev: the pci device
 108  * @cfg_type: the VIRTIO_PCI_CAP_* value we seek
 109  * @ioresource_types: IORESOURCE_MEM and/or IORESOURCE_IO.
 110  * @bars: the bitmask of BARs
 111  *
 112  * Returns offset of the capability, or 0.
 113  */
 114 static inline int virtio_pci_find_capability(struct pci_dev *dev, u8 cfg_type,
 115                                              u32 ioresource_types, int *bars)
 116 {
 117         int pos;
 118
 119         for (pos = pci_find_capability(dev, PCI_CAP_ID_VNDR);
 120              pos > 0;
 121              pos = pci_find_next_capability(dev, pos, PCI_CAP_ID_VNDR)) {
 122                 u8 type, bar;
 123                 pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap,
 124                                                          cfg_type),
 125                                      &type);
 126                 pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap,
 127                                                          bar),
 128                                      &bar);
 129
 130                 /* Ignore structures with reserved BAR values */
 131                 if (bar >= PCI_STD_NUM_BARS)
 132                         continue;
 133
 134                 if (type == cfg_type) {
 135                         if (pci_resource_len(dev, bar) &&
 136                             pci_resource_flags(dev, bar) & ioresource_types) {
 137                                 *bars |= (1 << bar);
 138                                 return pos;
 139                         }
 140                 }
 141         }
 142         return 0;
 143 }
 144
 145 /* This is part of the ABI.  Don't screw with it. */
 146 static inline void check_offsets(void)
 147 {
 148         /* Note: disk space was harmed in compilation of this function. */
 149         BUILD_BUG_ON(VIRTIO_PCI_CAP_VNDR !=
 150                      offsetof(struct virtio_pci_cap, cap_vndr));
 151         BUILD_BUG_ON(VIRTIO_PCI_CAP_NEXT !=
 152                      offsetof(struct virtio_pci_cap, cap_next));
 153         BUILD_BUG_ON(VIRTIO_PCI_CAP_LEN !=
 154                      offsetof(struct virtio_pci_cap, cap_len));
 155         BUILD_BUG_ON(VIRTIO_PCI_CAP_CFG_TYPE !=
 156                      offsetof(struct virtio_pci_cap, cfg_type));
 157         BUILD_BUG_ON(VIRTIO_PCI_CAP_BAR !=
 158                      offsetof(struct virtio_pci_cap, bar));
 159         BUILD_BUG_ON(VIRTIO_PCI_CAP_OFFSET !=
 160                      offsetof(struct virtio_pci_cap, offset));
 161         BUILD_BUG_ON(VIRTIO_PCI_CAP_LENGTH !=
 162                      offsetof(struct virtio_pci_cap, length));
 163         BUILD_BUG_ON(VIRTIO_PCI_NOTIFY_CAP_MULT !=
 164                      offsetof(struct virtio_pci_notify_cap,
 165                               notify_off_multiplier));
 166         BUILD_BUG_ON(VIRTIO_PCI_COMMON_DFSELECT !=
 167                      offsetof(struct virtio_pci_common_cfg,
 168                               device_feature_select));
 169         BUILD_BUG_ON(VIRTIO_PCI_COMMON_DF !=
 170                      offsetof(struct virtio_pci_common_cfg, device_feature));
 171         BUILD_BUG_ON(VIRTIO_PCI_COMMON_GFSELECT !=
 172                      offsetof(struct virtio_pci_common_cfg,
 173                               guest_feature_select));
 174         BUILD_BUG_ON(VIRTIO_PCI_COMMON_GF !=
 175                      offsetof(struct virtio_pci_common_cfg, guest_feature));
 176         BUILD_BUG_ON(VIRTIO_PCI_COMMON_MSIX !=
 177                      offsetof(struct virtio_pci_common_cfg, msix_config));
 178         BUILD_BUG_ON(VIRTIO_PCI_COMMON_NUMQ !=
 179                      offsetof(struct virtio_pci_common_cfg, num_queues));
 180         BUILD_BUG_ON(VIRTIO_PCI_COMMON_STATUS !=
 181                      offsetof(struct virtio_pci_common_cfg, device_status));
 182         BUILD_BUG_ON(VIRTIO_PCI_COMMON_CFGGENERATION !=
 183                      offsetof(struct virtio_pci_common_cfg, config_generation));
 184         BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SELECT !=
 185                      offsetof(struct virtio_pci_common_cfg, queue_select));
 186         BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SIZE !=
 187                      offsetof(struct virtio_pci_common_cfg, queue_size));
 188         BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_MSIX !=
 189                      offsetof(struct virtio_pci_common_cfg, queue_msix_vector));
 190         BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_ENABLE !=
 191                      offsetof(struct virtio_pci_common_cfg, queue_enable));
 192         BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_NOFF !=
 193                      offsetof(struct virtio_pci_common_cfg, queue_notify_off));
 194         BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCLO !=
 195                      offsetof(struct virtio_pci_common_cfg, queue_desc_lo));
 196         BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCHI !=
 197                      offsetof(struct virtio_pci_common_cfg, queue_desc_hi));
 198         BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILLO !=
 199                      offsetof(struct virtio_pci_common_cfg, queue_avail_lo));
 200         BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILHI !=
 201                      offsetof(struct virtio_pci_common_cfg, queue_avail_hi));
 202         BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDLO !=
 203                      offsetof(struct virtio_pci_common_cfg, queue_used_lo));
 204         BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDHI !=
 205                      offsetof(struct virtio_pci_common_cfg, queue_used_hi));
 206         BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_NDATA !=
 207                      offsetof(struct virtio_pci_modern_common_cfg, queue_notify_data));
 208         BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_RESET !=
 209                      offsetof(struct virtio_pci_modern_common_cfg, queue_reset));
 210         BUILD_BUG_ON(VIRTIO_PCI_COMMON_ADM_Q_IDX !=
 211                      offsetof(struct virtio_pci_modern_common_cfg, admin_queue_index));
 212         BUILD_BUG_ON(VIRTIO_PCI_COMMON_ADM_Q_NUM !=
 213                      offsetof(struct virtio_pci_modern_common_cfg, admin_queue_num));
 214 }
 215
 216 /*
 217  * vp_modern_probe: probe the modern virtio pci device, note that the
 218  * caller is required to enable PCI device before calling this function.
 219  * @mdev: the modern virtio-pci device
 220  *
 221  * Return 0 on succeed otherwise fail
 222  */
 223 int vp_modern_probe(struct virtio_pci_modern_device *mdev)
 224 {
 225         struct pci_dev *pci_dev = mdev->pci_dev;
 226         int err, common, isr, notify, device;
 227         u32 notify_length;
 228         u32 notify_offset;
 229         int devid;
 230
 231         check_offsets();
 232
 233         if (mdev->device_id_check) {
 234                 devid = mdev->device_id_check(pci_dev);
 235                 if (devid < 0)
 236                         return devid;
 237                 mdev->id.device = devid;
 238         } else {
 239                 /* We only own devices >= 0x1000 and <= 0x107f: leave the rest. */
 240                 if (pci_dev->device < 0x1000 || pci_dev->device > 0x107f)
 241                         return -ENODEV;
 242
 243                 if (pci_dev->device < 0x1040) {
 244                         /* Transitional devices: use the PCI subsystem device id as
 245                          * virtio device id, same as legacy driver always did.
 246                          */
 247                         mdev->id.device = pci_dev->subsystem_device;
 248                 } else {
 249                         /* Modern devices: simply use PCI device id, but start from 0x1040. */
 250                         mdev->id.device = pci_dev->device - 0x1040;
 251                 }
 252         }
 253         mdev->id.vendor = pci_dev->subsystem_vendor;
 254
 255         /* check for a common config: if not, use legacy mode (bar 0). */
 256         common = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_COMMON_CFG,
 257                                             IORESOURCE_IO | IORESOURCE_MEM,
 258                                             &mdev->modern_bars);
 259         if (!common) {
 260                 dev_info(&pci_dev->dev,
 261                          "virtio_pci: leaving for legacy driver\n");
 262                 return -ENODEV;
 263         }
 264
 265         /* If common is there, these should be too... */
 266         isr = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_ISR_CFG,
 267                                          IORESOURCE_IO | IORESOURCE_MEM,
 268                                          &mdev->modern_bars);
 269         notify = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_NOTIFY_CFG,
 270                                             IORESOURCE_IO | IORESOURCE_MEM,
 271                                             &mdev->modern_bars);
 272         if (!isr || !notify) {
 273                 dev_err(&pci_dev->dev,
 274                         "virtio_pci: missing capabilities %i/%i/%i\n",
 275                         common, isr, notify);
 276                 return -EINVAL;
 277         }
 278
 279         err = dma_set_mask_and_coherent(&pci_dev->dev,
 280                                         mdev->dma_mask ? : DMA_BIT_MASK(64));
 281         if (err)
 282                 err = dma_set_mask_and_coherent(&pci_dev->dev,
 283                                                 DMA_BIT_MASK(32));
 284         if (err)
 285                 dev_warn(&pci_dev->dev, "Failed to enable 64-bit or 32-bit DMA.  Trying to continue, but this might not work.\n");
 286
 287         /* Device capability is only mandatory for devices that have
 288          * device-specific configuration.
 289          */
 290         device = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_DEVICE_CFG,
 291                                             IORESOURCE_IO | IORESOURCE_MEM,
 292                                             &mdev->modern_bars);
 293
 294         err = pci_request_selected_regions(pci_dev, mdev->modern_bars,
 295                                            "virtio-pci-modern");
 296         if (err)
 297                 return err;
 298
 299         err = -EINVAL;
 300         mdev->common = vp_modern_map_capability(mdev, common,
 301                               sizeof(struct virtio_pci_common_cfg), 4, 0,
 302                               offsetofend(struct virtio_pci_modern_common_cfg,
 303                                           admin_queue_num),
 304                               &mdev->common_len, NULL);
 305         if (!mdev->common)
 306                 goto err_map_common;
 307         mdev->isr = vp_modern_map_capability(mdev, isr, sizeof(u8), 1,
 308                                              0, 1,
 309                                              NULL, NULL);
 310         if (!mdev->isr)
 311                 goto err_map_isr;
 312
 313         /* Read notify_off_multiplier from config space. */
 314         pci_read_config_dword(pci_dev,
 315                               notify + offsetof(struct virtio_pci_notify_cap,
 316                                                 notify_off_multiplier),
 317                               &mdev->notify_offset_multiplier);
 318         /* Read notify length and offset from config space. */
 319         pci_read_config_dword(pci_dev,
 320                               notify + offsetof(struct virtio_pci_notify_cap,
 321                                                 cap.length),
 322                               &notify_length);
 323
 324         pci_read_config_dword(pci_dev,
 325                               notify + offsetof(struct virtio_pci_notify_cap,
 326                                                 cap.offset),
 327                               &notify_offset);
 328
 329         /* We don't know how many VQs we'll map, ahead of the time.
 330          * If notify length is small, map it all now.
 331          * Otherwise, map each VQ individually later.
 332          */
 333         if ((u64)notify_length + (notify_offset % PAGE_SIZE) <= PAGE_SIZE) {
 334                 mdev->notify_base = vp_modern_map_capability(mdev, notify,
 335                                                              2, 2,
 336                                                              0, notify_length,
 337                                                              &mdev->notify_len,
 338                                                              &mdev->notify_pa);
 339                 if (!mdev->notify_base)
 340                         goto err_map_notify;
 341         } else {
 342                 mdev->notify_map_cap = notify;
 343         }
 344
 345         /* Again, we don't know how much we should map, but PAGE_SIZE
 346          * is more than enough for all existing devices.
 347          */
 348         if (device) {
 349                 mdev->device = vp_modern_map_capability(mdev, device, 0, 4,
 350                                                         0, PAGE_SIZE,
 351                                                         &mdev->device_len,
 352                                                         NULL);
 353                 if (!mdev->device)
 354                         goto err_map_device;
 355         }
 356
 357         return 0;
 358
 359 err_map_device:
 360         if (mdev->notify_base)
 361                 pci_iounmap(pci_dev, mdev->notify_base);
 362 err_map_notify:
 363         pci_iounmap(pci_dev, mdev->isr);
 364 err_map_isr:
 365         pci_iounmap(pci_dev, mdev->common);
 366 err_map_common:
 367         pci_release_selected_regions(pci_dev, mdev->modern_bars);
 368         return err;
 369 }
 370 EXPORT_SYMBOL_GPL(vp_modern_probe);
 371
 372 /*
 373  * vp_modern_remove: remove and cleanup the modern virtio pci device
 374  * @mdev: the modern virtio-pci device
 375  */
 376 void vp_modern_remove(struct virtio_pci_modern_device *mdev)
 377 {
 378         struct pci_dev *pci_dev = mdev->pci_dev;
 379
 380         if (mdev->device)
 381                 pci_iounmap(pci_dev, mdev->device);
 382         if (mdev->notify_base)
 383                 pci_iounmap(pci_dev, mdev->notify_base);
 384         pci_iounmap(pci_dev, mdev->isr);
 385         pci_iounmap(pci_dev, mdev->common);
 386         pci_release_selected_regions(pci_dev, mdev->modern_bars);
 387 }
 388 EXPORT_SYMBOL_GPL(vp_modern_remove);
 389
 390 /*
 391  * vp_modern_get_features - get features from device
 392  * @mdev: the modern virtio-pci device
 393  *
 394  * Returns the features read from the device
 395  */
 396 u64 vp_modern_get_features(struct virtio_pci_modern_device *mdev)
 397 {
 398         struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
 399
 400         u64 features;
 401
 402         vp_iowrite32(0, &cfg->device_feature_select);
 403         features = vp_ioread32(&cfg->device_feature);
 404         vp_iowrite32(1, &cfg->device_feature_select);
 405         features |= ((u64)vp_ioread32(&cfg->device_feature) << 32);
 406
 407         return features;
 408 }
 409 EXPORT_SYMBOL_GPL(vp_modern_get_features);
 410
 411 /*
 412  * vp_modern_get_driver_features - get driver features from device
 413  * @mdev: the modern virtio-pci device
 414  *
 415  * Returns the driver features read from the device
 416  */
 417 u64 vp_modern_get_driver_features(struct virtio_pci_modern_device *mdev)
 418 {
 419         struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
 420
 421         u64 features;
 422
 423         vp_iowrite32(0, &cfg->guest_feature_select);
 424         features = vp_ioread32(&cfg->guest_feature);
 425         vp_iowrite32(1, &cfg->guest_feature_select);
 426         features |= ((u64)vp_ioread32(&cfg->guest_feature) << 32);
 427
 428         return features;
 429 }
 430 EXPORT_SYMBOL_GPL(vp_modern_get_driver_features);
 431
 432 /*
 433  * vp_modern_set_features - set features to device
 434  * @mdev: the modern virtio-pci device
 435  * @features: the features set to device
 436  */
 437 void vp_modern_set_features(struct virtio_pci_modern_device *mdev,
 438                             u64 features)
 439 {
 440         struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
 441
 442         vp_iowrite32(0, &cfg->guest_feature_select);
 443         vp_iowrite32((u32)features, &cfg->guest_feature);
 444         vp_iowrite32(1, &cfg->guest_feature_select);
 445         vp_iowrite32(features >> 32, &cfg->guest_feature);
 446 }
 447 EXPORT_SYMBOL_GPL(vp_modern_set_features);
 448
 449 /*
 450  * vp_modern_generation - get the device genreation
 451  * @mdev: the modern virtio-pci device
 452  *
 453  * Returns the genreation read from device
 454  */
 455 u32 vp_modern_generation(struct virtio_pci_modern_device *mdev)
 456 {
 457         struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
 458
 459         return vp_ioread8(&cfg->config_generation);
 460 }
 461 EXPORT_SYMBOL_GPL(vp_modern_generation);
 462
 463 /*
 464  * vp_modern_get_status - get the device status
 465  * @mdev: the modern virtio-pci device
 466  *
 467  * Returns the status read from device
 468  */
 469 u8 vp_modern_get_status(struct virtio_pci_modern_device *mdev)
 470 {
 471         struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
 472
 473         return vp_ioread8(&cfg->device_status);
 474 }
 475 EXPORT_SYMBOL_GPL(vp_modern_get_status);
 476
 477 /*
 478  * vp_modern_set_status - set status to device
 479  * @mdev: the modern virtio-pci device
 480  * @status: the status set to device
 481  */
 482 void vp_modern_set_status(struct virtio_pci_modern_device *mdev,
 483                                  u8 status)
 484 {
 485         struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
 486
 487         /*
 488          * Per memory-barriers.txt, wmb() is not needed to guarantee
 489          * that the cache coherent memory writes have completed
 490          * before writing to the MMIO region.
 491          */
 492         vp_iowrite8(status, &cfg->device_status);
 493 }
 494 EXPORT_SYMBOL_GPL(vp_modern_set_status);
 495
 496 /*
 497  * vp_modern_get_queue_reset - get the queue reset status
 498  * @mdev: the modern virtio-pci device
 499  * @index: queue index
 500  */
 501 int vp_modern_get_queue_reset(struct virtio_pci_modern_device *mdev, u16 index)
 502 {
 503         struct virtio_pci_modern_common_cfg __iomem *cfg;
 504
 505         cfg = (struct virtio_pci_modern_common_cfg __iomem *)mdev->common;
 506
 507         vp_iowrite16(index, &cfg->cfg.queue_select);
 508         return vp_ioread16(&cfg->queue_reset);
 509 }
 510 EXPORT_SYMBOL_GPL(vp_modern_get_queue_reset);
 511
 512 /*
 513  * vp_modern_set_queue_reset - reset the queue
 514  * @mdev: the modern virtio-pci device
 515  * @index: queue index
 516  */
 517 void vp_modern_set_queue_reset(struct virtio_pci_modern_device *mdev, u16 index)
 518 {
 519         struct virtio_pci_modern_common_cfg __iomem *cfg;
 520
 521         cfg = (struct virtio_pci_modern_common_cfg __iomem *)mdev->common;
 522
 523         vp_iowrite16(index, &cfg->cfg.queue_select);
 524         vp_iowrite16(1, &cfg->queue_reset);
 525
 526         while (vp_ioread16(&cfg->queue_reset))
 527                 msleep(1);
 528
 529         while (vp_ioread16(&cfg->cfg.queue_enable))
 530                 msleep(1);
 531 }
 532 EXPORT_SYMBOL_GPL(vp_modern_set_queue_reset);
 533
 534 /*
 535  * vp_modern_queue_vector - set the MSIX vector for a specific virtqueue
 536  * @mdev: the modern virtio-pci device
 537  * @index: queue index
 538  * @vector: the config vector
 539  *
 540  * Returns the config vector read from the device
 541  */
 542 u16 vp_modern_queue_vector(struct virtio_pci_modern_device *mdev,
 543                            u16 index, u16 vector)
 544 {
 545         struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
 546
 547         vp_iowrite16(index, &cfg->queue_select);
 548         vp_iowrite16(vector, &cfg->queue_msix_vector);
 549         /* Flush the write out to device */
 550         return vp_ioread16(&cfg->queue_msix_vector);
 551 }
 552 EXPORT_SYMBOL_GPL(vp_modern_queue_vector);
 553
 554 /*
 555  * vp_modern_config_vector - set the vector for config interrupt
 556  * @mdev: the modern virtio-pci device
 557  * @vector: the config vector
 558  *
 559  * Returns the config vector read from the device
 560  */
 561 u16 vp_modern_config_vector(struct virtio_pci_modern_device *mdev,
 562                             u16 vector)
 563 {
 564         struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
 565
 566         /* Setup the vector used for configuration events */
 567         vp_iowrite16(vector, &cfg->msix_config);
 568         /* Verify we had enough resources to assign the vector */
 569         /* Will also flush the write out to device */
 570         return vp_ioread16(&cfg->msix_config);
 571 }
 572 EXPORT_SYMBOL_GPL(vp_modern_config_vector);
 573
 574 /*
 575  * vp_modern_queue_address - set the virtqueue address
 576  * @mdev: the modern virtio-pci device
 577  * @index: the queue index
 578  * @desc_addr: address of the descriptor area
 579  * @driver_addr: address of the driver area
 580  * @device_addr: address of the device area
 581  */
 582 void vp_modern_queue_address(struct virtio_pci_modern_device *mdev,
 583                              u16 index, u64 desc_addr, u64 driver_addr,
 584                              u64 device_addr)
 585 {
 586         struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
 587
 588         vp_iowrite16(index, &cfg->queue_select);
 589
 590         vp_iowrite64_twopart(desc_addr, &cfg->queue_desc_lo,
 591                              &cfg->queue_desc_hi);
 592         vp_iowrite64_twopart(driver_addr, &cfg->queue_avail_lo,
 593                              &cfg->queue_avail_hi);
 594         vp_iowrite64_twopart(device_addr, &cfg->queue_used_lo,
 595                              &cfg->queue_used_hi);
 596 }
 597 EXPORT_SYMBOL_GPL(vp_modern_queue_address);
 598
 599 /*
 600  * vp_modern_set_queue_enable - enable a virtqueue
 601  * @mdev: the modern virtio-pci device
 602  * @index: the queue index
 603  * @enable: whether the virtqueue is enable or not
 604  */
 605 void vp_modern_set_queue_enable(struct virtio_pci_modern_device *mdev,
 606                                 u16 index, bool enable)
 607 {
 608         vp_iowrite16(index, &mdev->common->queue_select);
 609         vp_iowrite16(enable, &mdev->common->queue_enable);
 610 }
 611 EXPORT_SYMBOL_GPL(vp_modern_set_queue_enable);
 612
 613 /*
 614  * vp_modern_get_queue_enable - enable a virtqueue
 615  * @mdev: the modern virtio-pci device
 616  * @index: the queue index
 617  *
 618  * Returns whether a virtqueue is enabled or not
 619  */
 620 bool vp_modern_get_queue_enable(struct virtio_pci_modern_device *mdev,
 621                                 u16 index)
 622 {
 623         vp_iowrite16(index, &mdev->common->queue_select);
 624
 625         return vp_ioread16(&mdev->common->queue_enable);
 626 }
 627 EXPORT_SYMBOL_GPL(vp_modern_get_queue_enable);
 628
 629 /*
 630  * vp_modern_set_queue_size - set size for a virtqueue
 631  * @mdev: the modern virtio-pci device
 632  * @index: the queue index
 633  * @size: the size of the virtqueue
 634  */
 635 void vp_modern_set_queue_size(struct virtio_pci_modern_device *mdev,
 636                               u16 index, u16 size)
 637 {
 638         vp_iowrite16(index, &mdev->common->queue_select);
 639         vp_iowrite16(size, &mdev->common->queue_size);
 640
 641 }
 642 EXPORT_SYMBOL_GPL(vp_modern_set_queue_size);
 643
 644 /*
 645  * vp_modern_get_queue_size - get size for a virtqueue
 646  * @mdev: the modern virtio-pci device
 647  * @index: the queue index
 648  *
 649  * Returns the size of the virtqueue
 650  */
 651 u16 vp_modern_get_queue_size(struct virtio_pci_modern_device *mdev,
 652                              u16 index)
 653 {
 654         vp_iowrite16(index, &mdev->common->queue_select);
 655
 656         return vp_ioread16(&mdev->common->queue_size);
 657
 658 }
 659 EXPORT_SYMBOL_GPL(vp_modern_get_queue_size);
 660
 661 /*
 662  * vp_modern_get_num_queues - get the number of virtqueues
 663  * @mdev: the modern virtio-pci device
 664  *
 665  * Returns the number of virtqueues
 666  */
 667 u16 vp_modern_get_num_queues(struct virtio_pci_modern_device *mdev)
 668 {
 669         return vp_ioread16(&mdev->common->num_queues);
 670 }
 671 EXPORT_SYMBOL_GPL(vp_modern_get_num_queues);
 672
 673 /*
 674  * vp_modern_get_queue_notify_off - get notification offset for a virtqueue
 675  * @mdev: the modern virtio-pci device
 676  * @index: the queue index
 677  *
 678  * Returns the notification offset for a virtqueue
 679  */
 680 static u16 vp_modern_get_queue_notify_off(struct virtio_pci_modern_device *mdev,
 681                                           u16 index)
 682 {
 683         vp_iowrite16(index, &mdev->common->queue_select);
 684
 685         return vp_ioread16(&mdev->common->queue_notify_off);
 686 }
 687
 688 /*
 689  * vp_modern_map_vq_notify - map notification area for a
 690  * specific virtqueue
 691  * @mdev: the modern virtio-pci device
 692  * @index: the queue index
 693  * @pa: the pointer to the physical address of the nofity area
 694  *
 695  * Returns the address of the notification area
 696  */
 697 void __iomem *vp_modern_map_vq_notify(struct virtio_pci_modern_device *mdev,
 698                                       u16 index, resource_size_t *pa)
 699 {
 700         u16 off = vp_modern_get_queue_notify_off(mdev, index);
 701
 702         if (mdev->notify_base) {
 703                 /* offset should not wrap */
 704                 if ((u64)off * mdev->notify_offset_multiplier + 2
 705                         > mdev->notify_len) {
 706                         dev_warn(&mdev->pci_dev->dev,
 707                                  "bad notification offset %u (x %u) "
 708                                  "for queue %u > %zd",
 709                                  off, mdev->notify_offset_multiplier,
 710                                  index, mdev->notify_len);
 711                         return NULL;
 712                 }
 713                 if (pa)
 714                         *pa = mdev->notify_pa +
 715                               off * mdev->notify_offset_multiplier;
 716                 return mdev->notify_base + off * mdev->notify_offset_multiplier;
 717         } else {
 718                 return vp_modern_map_capability(mdev,
 719                                        mdev->notify_map_cap, 2, 2,
 720                                        off * mdev->notify_offset_multiplier, 2,
 721                                        NULL, pa);
 722         }
 723 }
 724 EXPORT_SYMBOL_GPL(vp_modern_map_vq_notify);
 725
 726 u16 vp_modern_avq_num(struct virtio_pci_modern_device *mdev)
 727 {
 728         struct virtio_pci_modern_common_cfg __iomem *cfg;
 729
 730         cfg = (struct virtio_pci_modern_common_cfg __iomem *)mdev->common;
 731         return vp_ioread16(&cfg->admin_queue_num);
 732 }
 733 EXPORT_SYMBOL_GPL(vp_modern_avq_num);
 734
 735 u16 vp_modern_avq_index(struct virtio_pci_modern_device *mdev)
 736 {
 737         struct virtio_pci_modern_common_cfg __iomem *cfg;
 738
 739         cfg = (struct virtio_pci_modern_common_cfg __iomem *)mdev->common;
 740         return vp_ioread16(&cfg->admin_queue_index);
 741 }
 742 EXPORT_SYMBOL_GPL(vp_modern_avq_index);
 743
 744 MODULE_VERSION("0.1");
 745 MODULE_DESCRIPTION("Modern Virtio PCI Device");
 746 MODULE_AUTHOR("Jason Wang <jasowang@redhat.com>");
 747 MODULE_LICENSE("GPL");