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