1 /* 2 * Virtio PCI driver - modern (virtio 1.0) device support 3 * 4 * This module allows virtio devices to be used over a virtual PCI device. 5 * This can be used with QEMU based VMMs like KVM or Xen. 6 * 7 * Copyright IBM Corp. 2007 8 * Copyright Red Hat, Inc. 2014 9 * 10 * Authors: 11 * Anthony Liguori <aliguori@us.ibm.com> 12 * Rusty Russell <rusty@rustcorp.com.au> 13 * Michael S. Tsirkin <mst@redhat.com> 14 * 15 * This work is licensed under the terms of the GNU GPL, version 2 or later. 16 * See the COPYING file in the top-level directory. 17 * 18 */ 19 20 #define VIRTIO_PCI_NO_LEGACY 21 #include "virtio_pci_common.h" 22 23 /* 24 * Type-safe wrappers for io accesses. 25 * Use these to enforce at compile time the following spec requirement: 26 * 27 * The driver MUST access each field using the “natural” access 28 * method, i.e. 32-bit accesses for 32-bit fields, 16-bit accesses 29 * for 16-bit fields and 8-bit accesses for 8-bit fields. 30 */ 31 static inline u8 vp_ioread8(u8 __iomem *addr) 32 { 33 return ioread8(addr); 34 } 35 static inline u16 vp_ioread16 (u16 __iomem *addr) 36 { 37 return ioread16(addr); 38 } 39 40 static inline u32 vp_ioread32(u32 __iomem *addr) 41 { 42 return ioread32(addr); 43 } 44 45 static inline void vp_iowrite8(u8 value, u8 __iomem *addr) 46 { 47 iowrite8(value, addr); 48 } 49 50 static inline void vp_iowrite16(u16 value, u16 __iomem *addr) 51 { 52 iowrite16(value, addr); 53 } 54 55 static inline void vp_iowrite32(u32 value, u32 __iomem *addr) 56 { 57 iowrite32(value, addr); 58 } 59 60 static void vp_iowrite64_twopart(u64 val, 61 __le32 __iomem *lo, __le32 __iomem *hi) 62 { 63 vp_iowrite32((u32)val, lo); 64 vp_iowrite32(val >> 32, hi); 65 } 66 67 static void __iomem *map_capability(struct pci_dev *dev, int off, 68 size_t minlen, 69 u32 align, 70 u32 start, u32 size, 71 size_t *len) 72 { 73 u8 bar; 74 u32 offset, length; 75 void __iomem *p; 76 77 pci_read_config_byte(dev, off + offsetof(struct virtio_pci_cap, 78 bar), 79 &bar); 80 pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, offset), 81 &offset); 82 pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, length), 83 &length); 84 85 if (length <= start) { 86 dev_err(&dev->dev, 87 "virtio_pci: bad capability len %u (>%u expected)\n", 88 length, start); 89 return NULL; 90 } 91 92 if (length - start < minlen) { 93 dev_err(&dev->dev, 94 "virtio_pci: bad capability len %u (>=%zu expected)\n", 95 length, minlen); 96 return NULL; 97 } 98 99 length -= start; 100 101 if (start + offset < offset) { 102 dev_err(&dev->dev, 103 "virtio_pci: map wrap-around %u+%u\n", 104 start, offset); 105 return NULL; 106 } 107 108 offset += start; 109 110 if (offset & (align - 1)) { 111 dev_err(&dev->dev, 112 "virtio_pci: offset %u not aligned to %u\n", 113 offset, align); 114 return NULL; 115 } 116 117 if (length > size) 118 length = size; 119 120 if (len) 121 *len = length; 122 123 if (minlen + offset < minlen || 124 minlen + offset > pci_resource_len(dev, bar)) { 125 dev_err(&dev->dev, 126 "virtio_pci: map virtio %zu@%u " 127 "out of range on bar %i length %lu\n", 128 minlen, offset, 129 bar, (unsigned long)pci_resource_len(dev, bar)); 130 return NULL; 131 } 132 133 p = pci_iomap_range(dev, bar, offset, length); 134 if (!p) 135 dev_err(&dev->dev, 136 "virtio_pci: unable to map virtio %u@%u on bar %i\n", 137 length, offset, bar); 138 return p; 139 } 140 141 /* virtio config->get_features() implementation */ 142 static u64 vp_get_features(struct virtio_device *vdev) 143 { 144 struct virtio_pci_device *vp_dev = to_vp_device(vdev); 145 u64 features; 146 147 vp_iowrite32(0, &vp_dev->common->device_feature_select); 148 features = vp_ioread32(&vp_dev->common->device_feature); 149 vp_iowrite32(1, &vp_dev->common->device_feature_select); 150 features |= ((u64)vp_ioread32(&vp_dev->common->device_feature) << 32); 151 152 return features; 153 } 154 155 /* virtio config->finalize_features() implementation */ 156 static int vp_finalize_features(struct virtio_device *vdev) 157 { 158 struct virtio_pci_device *vp_dev = to_vp_device(vdev); 159 160 /* Give virtio_ring a chance to accept features. */ 161 vring_transport_features(vdev); 162 163 if (!__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) { 164 dev_err(&vdev->dev, "virtio: device uses modern interface " 165 "but does not have VIRTIO_F_VERSION_1\n"); 166 return -EINVAL; 167 } 168 169 vp_iowrite32(0, &vp_dev->common->guest_feature_select); 170 vp_iowrite32((u32)vdev->features, &vp_dev->common->guest_feature); 171 vp_iowrite32(1, &vp_dev->common->guest_feature_select); 172 vp_iowrite32(vdev->features >> 32, &vp_dev->common->guest_feature); 173 174 return 0; 175 } 176 177 /* virtio config->get() implementation */ 178 static void vp_get(struct virtio_device *vdev, unsigned offset, 179 void *buf, unsigned len) 180 { 181 struct virtio_pci_device *vp_dev = to_vp_device(vdev); 182 u8 b; 183 __le16 w; 184 __le32 l; 185 186 BUG_ON(offset + len > vp_dev->device_len); 187 188 switch (len) { 189 case 1: 190 b = ioread8(vp_dev->device + offset); 191 memcpy(buf, &b, sizeof b); 192 break; 193 case 2: 194 w = cpu_to_le16(ioread16(vp_dev->device + offset)); 195 memcpy(buf, &w, sizeof w); 196 break; 197 case 4: 198 l = cpu_to_le32(ioread32(vp_dev->device + offset)); 199 memcpy(buf, &l, sizeof l); 200 break; 201 case 8: 202 l = cpu_to_le32(ioread32(vp_dev->device + offset)); 203 memcpy(buf, &l, sizeof l); 204 l = cpu_to_le32(ioread32(vp_dev->device + offset + sizeof l)); 205 memcpy(buf + sizeof l, &l, sizeof l); 206 break; 207 default: 208 BUG(); 209 } 210 } 211 212 /* the config->set() implementation. it's symmetric to the config->get() 213 * implementation */ 214 static void vp_set(struct virtio_device *vdev, unsigned offset, 215 const void *buf, unsigned len) 216 { 217 struct virtio_pci_device *vp_dev = to_vp_device(vdev); 218 u8 b; 219 __le16 w; 220 __le32 l; 221 222 BUG_ON(offset + len > vp_dev->device_len); 223 224 switch (len) { 225 case 1: 226 memcpy(&b, buf, sizeof b); 227 iowrite8(b, vp_dev->device + offset); 228 break; 229 case 2: 230 memcpy(&w, buf, sizeof w); 231 iowrite16(le16_to_cpu(w), vp_dev->device + offset); 232 break; 233 case 4: 234 memcpy(&l, buf, sizeof l); 235 iowrite32(le32_to_cpu(l), vp_dev->device + offset); 236 break; 237 case 8: 238 memcpy(&l, buf, sizeof l); 239 iowrite32(le32_to_cpu(l), vp_dev->device + offset); 240 memcpy(&l, buf + sizeof l, sizeof l); 241 iowrite32(le32_to_cpu(l), vp_dev->device + offset + sizeof l); 242 break; 243 default: 244 BUG(); 245 } 246 } 247 248 static u32 vp_generation(struct virtio_device *vdev) 249 { 250 struct virtio_pci_device *vp_dev = to_vp_device(vdev); 251 return vp_ioread8(&vp_dev->common->config_generation); 252 } 253 254 /* config->{get,set}_status() implementations */ 255 static u8 vp_get_status(struct virtio_device *vdev) 256 { 257 struct virtio_pci_device *vp_dev = to_vp_device(vdev); 258 return vp_ioread8(&vp_dev->common->device_status); 259 } 260 261 static void vp_set_status(struct virtio_device *vdev, u8 status) 262 { 263 struct virtio_pci_device *vp_dev = to_vp_device(vdev); 264 /* We should never be setting status to 0. */ 265 BUG_ON(status == 0); 266 vp_iowrite8(status, &vp_dev->common->device_status); 267 } 268 269 static void vp_reset(struct virtio_device *vdev) 270 { 271 struct virtio_pci_device *vp_dev = to_vp_device(vdev); 272 /* 0 status means a reset. */ 273 vp_iowrite8(0, &vp_dev->common->device_status); 274 /* Flush out the status write, and flush in device writes, 275 * including MSI-X interrupts, if any. */ 276 vp_ioread8(&vp_dev->common->device_status); 277 /* Flush pending VQ/configuration callbacks. */ 278 vp_synchronize_vectors(vdev); 279 } 280 281 static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector) 282 { 283 /* Setup the vector used for configuration events */ 284 vp_iowrite16(vector, &vp_dev->common->msix_config); 285 /* Verify we had enough resources to assign the vector */ 286 /* Will also flush the write out to device */ 287 return vp_ioread16(&vp_dev->common->msix_config); 288 } 289 290 static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev, 291 struct virtio_pci_vq_info *info, 292 unsigned index, 293 void (*callback)(struct virtqueue *vq), 294 const char *name, 295 u16 msix_vec) 296 { 297 struct virtio_pci_common_cfg __iomem *cfg = vp_dev->common; 298 struct virtqueue *vq; 299 u16 num, off; 300 int err; 301 302 if (index >= vp_ioread16(&cfg->num_queues)) 303 return ERR_PTR(-ENOENT); 304 305 /* Select the queue we're interested in */ 306 vp_iowrite16(index, &cfg->queue_select); 307 308 /* Check if queue is either not available or already active. */ 309 num = vp_ioread16(&cfg->queue_size); 310 if (!num || vp_ioread16(&cfg->queue_enable)) 311 return ERR_PTR(-ENOENT); 312 313 if (num & (num - 1)) { 314 dev_warn(&vp_dev->pci_dev->dev, "bad queue size %u", num); 315 return ERR_PTR(-EINVAL); 316 } 317 318 /* get offset of notification word for this vq */ 319 off = vp_ioread16(&cfg->queue_notify_off); 320 321 info->msix_vector = msix_vec; 322 323 /* create the vring */ 324 vq = vring_create_virtqueue(index, num, 325 SMP_CACHE_BYTES, &vp_dev->vdev, 326 true, true, vp_notify, callback, name); 327 if (!vq) 328 return ERR_PTR(-ENOMEM); 329 330 /* activate the queue */ 331 vp_iowrite16(virtqueue_get_vring_size(vq), &cfg->queue_size); 332 vp_iowrite64_twopart(virtqueue_get_desc_addr(vq), 333 &cfg->queue_desc_lo, &cfg->queue_desc_hi); 334 vp_iowrite64_twopart(virtqueue_get_avail_addr(vq), 335 &cfg->queue_avail_lo, &cfg->queue_avail_hi); 336 vp_iowrite64_twopart(virtqueue_get_used_addr(vq), 337 &cfg->queue_used_lo, &cfg->queue_used_hi); 338 339 if (vp_dev->notify_base) { 340 /* offset should not wrap */ 341 if ((u64)off * vp_dev->notify_offset_multiplier + 2 342 > vp_dev->notify_len) { 343 dev_warn(&vp_dev->pci_dev->dev, 344 "bad notification offset %u (x %u) " 345 "for queue %u > %zd", 346 off, vp_dev->notify_offset_multiplier, 347 index, vp_dev->notify_len); 348 err = -EINVAL; 349 goto err_map_notify; 350 } 351 vq->priv = (void __force *)vp_dev->notify_base + 352 off * vp_dev->notify_offset_multiplier; 353 } else { 354 vq->priv = (void __force *)map_capability(vp_dev->pci_dev, 355 vp_dev->notify_map_cap, 2, 2, 356 off * vp_dev->notify_offset_multiplier, 2, 357 NULL); 358 } 359 360 if (!vq->priv) { 361 err = -ENOMEM; 362 goto err_map_notify; 363 } 364 365 if (msix_vec != VIRTIO_MSI_NO_VECTOR) { 366 vp_iowrite16(msix_vec, &cfg->queue_msix_vector); 367 msix_vec = vp_ioread16(&cfg->queue_msix_vector); 368 if (msix_vec == VIRTIO_MSI_NO_VECTOR) { 369 err = -EBUSY; 370 goto err_assign_vector; 371 } 372 } 373 374 return vq; 375 376 err_assign_vector: 377 if (!vp_dev->notify_base) 378 pci_iounmap(vp_dev->pci_dev, (void __iomem __force *)vq->priv); 379 err_map_notify: 380 vring_del_virtqueue(vq); 381 return ERR_PTR(err); 382 } 383 384 static int vp_modern_find_vqs(struct virtio_device *vdev, unsigned nvqs, 385 struct virtqueue *vqs[], 386 vq_callback_t *callbacks[], 387 const char * const names[]) 388 { 389 struct virtio_pci_device *vp_dev = to_vp_device(vdev); 390 struct virtqueue *vq; 391 int rc = vp_find_vqs(vdev, nvqs, vqs, callbacks, names); 392 393 if (rc) 394 return rc; 395 396 /* Select and activate all queues. Has to be done last: once we do 397 * this, there's no way to go back except reset. 398 */ 399 list_for_each_entry(vq, &vdev->vqs, list) { 400 vp_iowrite16(vq->index, &vp_dev->common->queue_select); 401 vp_iowrite16(1, &vp_dev->common->queue_enable); 402 } 403 404 return 0; 405 } 406 407 static void del_vq(struct virtio_pci_vq_info *info) 408 { 409 struct virtqueue *vq = info->vq; 410 struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); 411 412 vp_iowrite16(vq->index, &vp_dev->common->queue_select); 413 414 if (vp_dev->msix_enabled) { 415 vp_iowrite16(VIRTIO_MSI_NO_VECTOR, 416 &vp_dev->common->queue_msix_vector); 417 /* Flush the write out to device */ 418 vp_ioread16(&vp_dev->common->queue_msix_vector); 419 } 420 421 if (!vp_dev->notify_base) 422 pci_iounmap(vp_dev->pci_dev, (void __force __iomem *)vq->priv); 423 424 vring_del_virtqueue(vq); 425 } 426 427 static const struct virtio_config_ops virtio_pci_config_nodev_ops = { 428 .get = NULL, 429 .set = NULL, 430 .generation = vp_generation, 431 .get_status = vp_get_status, 432 .set_status = vp_set_status, 433 .reset = vp_reset, 434 .find_vqs = vp_modern_find_vqs, 435 .del_vqs = vp_del_vqs, 436 .get_features = vp_get_features, 437 .finalize_features = vp_finalize_features, 438 .bus_name = vp_bus_name, 439 .set_vq_affinity = vp_set_vq_affinity, 440 }; 441 442 static const struct virtio_config_ops virtio_pci_config_ops = { 443 .get = vp_get, 444 .set = vp_set, 445 .generation = vp_generation, 446 .get_status = vp_get_status, 447 .set_status = vp_set_status, 448 .reset = vp_reset, 449 .find_vqs = vp_modern_find_vqs, 450 .del_vqs = vp_del_vqs, 451 .get_features = vp_get_features, 452 .finalize_features = vp_finalize_features, 453 .bus_name = vp_bus_name, 454 .set_vq_affinity = vp_set_vq_affinity, 455 }; 456 457 /** 458 * virtio_pci_find_capability - walk capabilities to find device info. 459 * @dev: the pci device 460 * @cfg_type: the VIRTIO_PCI_CAP_* value we seek 461 * @ioresource_types: IORESOURCE_MEM and/or IORESOURCE_IO. 462 * 463 * Returns offset of the capability, or 0. 464 */ 465 static inline int virtio_pci_find_capability(struct pci_dev *dev, u8 cfg_type, 466 u32 ioresource_types, int *bars) 467 { 468 int pos; 469 470 for (pos = pci_find_capability(dev, PCI_CAP_ID_VNDR); 471 pos > 0; 472 pos = pci_find_next_capability(dev, pos, PCI_CAP_ID_VNDR)) { 473 u8 type, bar; 474 pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, 475 cfg_type), 476 &type); 477 pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, 478 bar), 479 &bar); 480 481 /* Ignore structures with reserved BAR values */ 482 if (bar > 0x5) 483 continue; 484 485 if (type == cfg_type) { 486 if (pci_resource_len(dev, bar) && 487 pci_resource_flags(dev, bar) & ioresource_types) { 488 *bars |= (1 << bar); 489 return pos; 490 } 491 } 492 } 493 return 0; 494 } 495 496 /* This is part of the ABI. Don't screw with it. */ 497 static inline void check_offsets(void) 498 { 499 /* Note: disk space was harmed in compilation of this function. */ 500 BUILD_BUG_ON(VIRTIO_PCI_CAP_VNDR != 501 offsetof(struct virtio_pci_cap, cap_vndr)); 502 BUILD_BUG_ON(VIRTIO_PCI_CAP_NEXT != 503 offsetof(struct virtio_pci_cap, cap_next)); 504 BUILD_BUG_ON(VIRTIO_PCI_CAP_LEN != 505 offsetof(struct virtio_pci_cap, cap_len)); 506 BUILD_BUG_ON(VIRTIO_PCI_CAP_CFG_TYPE != 507 offsetof(struct virtio_pci_cap, cfg_type)); 508 BUILD_BUG_ON(VIRTIO_PCI_CAP_BAR != 509 offsetof(struct virtio_pci_cap, bar)); 510 BUILD_BUG_ON(VIRTIO_PCI_CAP_OFFSET != 511 offsetof(struct virtio_pci_cap, offset)); 512 BUILD_BUG_ON(VIRTIO_PCI_CAP_LENGTH != 513 offsetof(struct virtio_pci_cap, length)); 514 BUILD_BUG_ON(VIRTIO_PCI_NOTIFY_CAP_MULT != 515 offsetof(struct virtio_pci_notify_cap, 516 notify_off_multiplier)); 517 BUILD_BUG_ON(VIRTIO_PCI_COMMON_DFSELECT != 518 offsetof(struct virtio_pci_common_cfg, 519 device_feature_select)); 520 BUILD_BUG_ON(VIRTIO_PCI_COMMON_DF != 521 offsetof(struct virtio_pci_common_cfg, device_feature)); 522 BUILD_BUG_ON(VIRTIO_PCI_COMMON_GFSELECT != 523 offsetof(struct virtio_pci_common_cfg, 524 guest_feature_select)); 525 BUILD_BUG_ON(VIRTIO_PCI_COMMON_GF != 526 offsetof(struct virtio_pci_common_cfg, guest_feature)); 527 BUILD_BUG_ON(VIRTIO_PCI_COMMON_MSIX != 528 offsetof(struct virtio_pci_common_cfg, msix_config)); 529 BUILD_BUG_ON(VIRTIO_PCI_COMMON_NUMQ != 530 offsetof(struct virtio_pci_common_cfg, num_queues)); 531 BUILD_BUG_ON(VIRTIO_PCI_COMMON_STATUS != 532 offsetof(struct virtio_pci_common_cfg, device_status)); 533 BUILD_BUG_ON(VIRTIO_PCI_COMMON_CFGGENERATION != 534 offsetof(struct virtio_pci_common_cfg, config_generation)); 535 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SELECT != 536 offsetof(struct virtio_pci_common_cfg, queue_select)); 537 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SIZE != 538 offsetof(struct virtio_pci_common_cfg, queue_size)); 539 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_MSIX != 540 offsetof(struct virtio_pci_common_cfg, queue_msix_vector)); 541 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_ENABLE != 542 offsetof(struct virtio_pci_common_cfg, queue_enable)); 543 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_NOFF != 544 offsetof(struct virtio_pci_common_cfg, queue_notify_off)); 545 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCLO != 546 offsetof(struct virtio_pci_common_cfg, queue_desc_lo)); 547 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCHI != 548 offsetof(struct virtio_pci_common_cfg, queue_desc_hi)); 549 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILLO != 550 offsetof(struct virtio_pci_common_cfg, queue_avail_lo)); 551 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILHI != 552 offsetof(struct virtio_pci_common_cfg, queue_avail_hi)); 553 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDLO != 554 offsetof(struct virtio_pci_common_cfg, queue_used_lo)); 555 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDHI != 556 offsetof(struct virtio_pci_common_cfg, queue_used_hi)); 557 } 558 559 /* the PCI probing function */ 560 int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev) 561 { 562 struct pci_dev *pci_dev = vp_dev->pci_dev; 563 int err, common, isr, notify, device; 564 u32 notify_length; 565 u32 notify_offset; 566 567 check_offsets(); 568 569 /* We only own devices >= 0x1000 and <= 0x107f: leave the rest. */ 570 if (pci_dev->device < 0x1000 || pci_dev->device > 0x107f) 571 return -ENODEV; 572 573 if (pci_dev->device < 0x1040) { 574 /* Transitional devices: use the PCI subsystem device id as 575 * virtio device id, same as legacy driver always did. 576 */ 577 vp_dev->vdev.id.device = pci_dev->subsystem_device; 578 } else { 579 /* Modern devices: simply use PCI device id, but start from 0x1040. */ 580 vp_dev->vdev.id.device = pci_dev->device - 0x1040; 581 } 582 vp_dev->vdev.id.vendor = pci_dev->subsystem_vendor; 583 584 /* check for a common config: if not, use legacy mode (bar 0). */ 585 common = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_COMMON_CFG, 586 IORESOURCE_IO | IORESOURCE_MEM, 587 &vp_dev->modern_bars); 588 if (!common) { 589 dev_info(&pci_dev->dev, 590 "virtio_pci: leaving for legacy driver\n"); 591 return -ENODEV; 592 } 593 594 /* If common is there, these should be too... */ 595 isr = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_ISR_CFG, 596 IORESOURCE_IO | IORESOURCE_MEM, 597 &vp_dev->modern_bars); 598 notify = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_NOTIFY_CFG, 599 IORESOURCE_IO | IORESOURCE_MEM, 600 &vp_dev->modern_bars); 601 if (!isr || !notify) { 602 dev_err(&pci_dev->dev, 603 "virtio_pci: missing capabilities %i/%i/%i\n", 604 common, isr, notify); 605 return -EINVAL; 606 } 607 608 err = dma_set_mask_and_coherent(&pci_dev->dev, DMA_BIT_MASK(64)); 609 if (err) 610 err = dma_set_mask_and_coherent(&pci_dev->dev, 611 DMA_BIT_MASK(32)); 612 if (err) 613 dev_warn(&pci_dev->dev, "Failed to enable 64-bit or 32-bit DMA. Trying to continue, but this might not work.\n"); 614 615 /* Device capability is only mandatory for devices that have 616 * device-specific configuration. 617 */ 618 device = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_DEVICE_CFG, 619 IORESOURCE_IO | IORESOURCE_MEM, 620 &vp_dev->modern_bars); 621 622 err = pci_request_selected_regions(pci_dev, vp_dev->modern_bars, 623 "virtio-pci-modern"); 624 if (err) 625 return err; 626 627 err = -EINVAL; 628 vp_dev->common = map_capability(pci_dev, common, 629 sizeof(struct virtio_pci_common_cfg), 4, 630 0, sizeof(struct virtio_pci_common_cfg), 631 NULL); 632 if (!vp_dev->common) 633 goto err_map_common; 634 vp_dev->isr = map_capability(pci_dev, isr, sizeof(u8), 1, 635 0, 1, 636 NULL); 637 if (!vp_dev->isr) 638 goto err_map_isr; 639 640 /* Read notify_off_multiplier from config space. */ 641 pci_read_config_dword(pci_dev, 642 notify + offsetof(struct virtio_pci_notify_cap, 643 notify_off_multiplier), 644 &vp_dev->notify_offset_multiplier); 645 /* Read notify length and offset from config space. */ 646 pci_read_config_dword(pci_dev, 647 notify + offsetof(struct virtio_pci_notify_cap, 648 cap.length), 649 ¬ify_length); 650 651 pci_read_config_dword(pci_dev, 652 notify + offsetof(struct virtio_pci_notify_cap, 653 cap.offset), 654 ¬ify_offset); 655 656 /* We don't know how many VQs we'll map, ahead of the time. 657 * If notify length is small, map it all now. 658 * Otherwise, map each VQ individually later. 659 */ 660 if ((u64)notify_length + (notify_offset % PAGE_SIZE) <= PAGE_SIZE) { 661 vp_dev->notify_base = map_capability(pci_dev, notify, 2, 2, 662 0, notify_length, 663 &vp_dev->notify_len); 664 if (!vp_dev->notify_base) 665 goto err_map_notify; 666 } else { 667 vp_dev->notify_map_cap = notify; 668 } 669 670 /* Again, we don't know how much we should map, but PAGE_SIZE 671 * is more than enough for all existing devices. 672 */ 673 if (device) { 674 vp_dev->device = map_capability(pci_dev, device, 0, 4, 675 0, PAGE_SIZE, 676 &vp_dev->device_len); 677 if (!vp_dev->device) 678 goto err_map_device; 679 680 vp_dev->vdev.config = &virtio_pci_config_ops; 681 } else { 682 vp_dev->vdev.config = &virtio_pci_config_nodev_ops; 683 } 684 685 vp_dev->config_vector = vp_config_vector; 686 vp_dev->setup_vq = setup_vq; 687 vp_dev->del_vq = del_vq; 688 689 return 0; 690 691 err_map_device: 692 if (vp_dev->notify_base) 693 pci_iounmap(pci_dev, vp_dev->notify_base); 694 err_map_notify: 695 pci_iounmap(pci_dev, vp_dev->isr); 696 err_map_isr: 697 pci_iounmap(pci_dev, vp_dev->common); 698 err_map_common: 699 return err; 700 } 701 702 void virtio_pci_modern_remove(struct virtio_pci_device *vp_dev) 703 { 704 struct pci_dev *pci_dev = vp_dev->pci_dev; 705 706 if (vp_dev->device) 707 pci_iounmap(pci_dev, vp_dev->device); 708 if (vp_dev->notify_base) 709 pci_iounmap(pci_dev, vp_dev->notify_base); 710 pci_iounmap(pci_dev, vp_dev->isr); 711 pci_iounmap(pci_dev, vp_dev->common); 712 pci_release_selected_regions(pci_dev, vp_dev->modern_bars); 713 } 714