1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Virtio PCI driver - modern (virtio 1.0) device support 4 * 5 * This module allows virtio devices to be used over a virtual PCI device. 6 * This can be used with QEMU based VMMs like KVM or Xen. 7 * 8 * Copyright IBM Corp. 2007 9 * Copyright Red Hat, Inc. 2014 10 * 11 * Authors: 12 * Anthony Liguori <aliguori@us.ibm.com> 13 * Rusty Russell <rusty@rustcorp.com.au> 14 * Michael S. Tsirkin <mst@redhat.com> 15 */ 16 17 #include <linux/delay.h> 18 #define VIRTIO_PCI_NO_LEGACY 19 #define VIRTIO_RING_NO_LEGACY 20 #include "virtio_pci_common.h" 21 22 /* 23 * Type-safe wrappers for io accesses. 24 * Use these to enforce at compile time the following spec requirement: 25 * 26 * The driver MUST access each field using the “natural” access 27 * method, i.e. 32-bit accesses for 32-bit fields, 16-bit accesses 28 * for 16-bit fields and 8-bit accesses for 8-bit fields. 29 */ 30 static inline u8 vp_ioread8(u8 __iomem *addr) 31 { 32 return ioread8(addr); 33 } 34 static inline u16 vp_ioread16 (__le16 __iomem *addr) 35 { 36 return ioread16(addr); 37 } 38 39 static inline u32 vp_ioread32(__le32 __iomem *addr) 40 { 41 return ioread32(addr); 42 } 43 44 static inline void vp_iowrite8(u8 value, u8 __iomem *addr) 45 { 46 iowrite8(value, addr); 47 } 48 49 static inline void vp_iowrite16(u16 value, __le16 __iomem *addr) 50 { 51 iowrite16(value, addr); 52 } 53 54 static inline void vp_iowrite32(u32 value, __le32 __iomem *addr) 55 { 56 iowrite32(value, addr); 57 } 58 59 static void vp_iowrite64_twopart(u64 val, 60 __le32 __iomem *lo, __le32 __iomem *hi) 61 { 62 vp_iowrite32((u32)val, lo); 63 vp_iowrite32(val >> 32, hi); 64 } 65 66 static void __iomem *map_capability(struct pci_dev *dev, int off, 67 size_t minlen, 68 u32 align, 69 u32 start, u32 size, 70 size_t *len) 71 { 72 u8 bar; 73 u32 offset, length; 74 void __iomem *p; 75 76 pci_read_config_byte(dev, off + offsetof(struct virtio_pci_cap, 77 bar), 78 &bar); 79 pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, offset), 80 &offset); 81 pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, length), 82 &length); 83 84 if (length <= start) { 85 dev_err(&dev->dev, 86 "virtio_pci: bad capability len %u (>%u expected)\n", 87 length, start); 88 return NULL; 89 } 90 91 if (length - start < minlen) { 92 dev_err(&dev->dev, 93 "virtio_pci: bad capability len %u (>=%zu expected)\n", 94 length, minlen); 95 return NULL; 96 } 97 98 length -= start; 99 100 if (start + offset < offset) { 101 dev_err(&dev->dev, 102 "virtio_pci: map wrap-around %u+%u\n", 103 start, offset); 104 return NULL; 105 } 106 107 offset += start; 108 109 if (offset & (align - 1)) { 110 dev_err(&dev->dev, 111 "virtio_pci: offset %u not aligned to %u\n", 112 offset, align); 113 return NULL; 114 } 115 116 if (length > size) 117 length = size; 118 119 if (len) 120 *len = length; 121 122 if (minlen + offset < minlen || 123 minlen + offset > pci_resource_len(dev, bar)) { 124 dev_err(&dev->dev, 125 "virtio_pci: map virtio %zu@%u " 126 "out of range on bar %i length %lu\n", 127 minlen, offset, 128 bar, (unsigned long)pci_resource_len(dev, bar)); 129 return NULL; 130 } 131 132 p = pci_iomap_range(dev, bar, offset, length); 133 if (!p) 134 dev_err(&dev->dev, 135 "virtio_pci: unable to map virtio %u@%u on bar %i\n", 136 length, offset, bar); 137 return p; 138 } 139 140 /* virtio config->get_features() implementation */ 141 static u64 vp_get_features(struct virtio_device *vdev) 142 { 143 struct virtio_pci_device *vp_dev = to_vp_device(vdev); 144 u64 features; 145 146 vp_iowrite32(0, &vp_dev->common->device_feature_select); 147 features = vp_ioread32(&vp_dev->common->device_feature); 148 vp_iowrite32(1, &vp_dev->common->device_feature_select); 149 features |= ((u64)vp_ioread32(&vp_dev->common->device_feature) << 32); 150 151 return features; 152 } 153 154 static void vp_transport_features(struct virtio_device *vdev, u64 features) 155 { 156 struct virtio_pci_device *vp_dev = to_vp_device(vdev); 157 struct pci_dev *pci_dev = vp_dev->pci_dev; 158 159 if ((features & BIT_ULL(VIRTIO_F_SR_IOV)) && 160 pci_find_ext_capability(pci_dev, PCI_EXT_CAP_ID_SRIOV)) 161 __virtio_set_bit(vdev, VIRTIO_F_SR_IOV); 162 } 163 164 /* virtio config->finalize_features() implementation */ 165 static int vp_finalize_features(struct virtio_device *vdev) 166 { 167 struct virtio_pci_device *vp_dev = to_vp_device(vdev); 168 u64 features = vdev->features; 169 170 /* Give virtio_ring a chance to accept features. */ 171 vring_transport_features(vdev); 172 173 /* Give virtio_pci a chance to accept features. */ 174 vp_transport_features(vdev, features); 175 176 if (!__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) { 177 dev_err(&vdev->dev, "virtio: device uses modern interface " 178 "but does not have VIRTIO_F_VERSION_1\n"); 179 return -EINVAL; 180 } 181 182 vp_iowrite32(0, &vp_dev->common->guest_feature_select); 183 vp_iowrite32((u32)vdev->features, &vp_dev->common->guest_feature); 184 vp_iowrite32(1, &vp_dev->common->guest_feature_select); 185 vp_iowrite32(vdev->features >> 32, &vp_dev->common->guest_feature); 186 187 return 0; 188 } 189 190 /* virtio config->get() implementation */ 191 static void vp_get(struct virtio_device *vdev, unsigned offset, 192 void *buf, unsigned len) 193 { 194 struct virtio_pci_device *vp_dev = to_vp_device(vdev); 195 u8 b; 196 __le16 w; 197 __le32 l; 198 199 BUG_ON(offset + len > vp_dev->device_len); 200 201 switch (len) { 202 case 1: 203 b = ioread8(vp_dev->device + offset); 204 memcpy(buf, &b, sizeof b); 205 break; 206 case 2: 207 w = cpu_to_le16(ioread16(vp_dev->device + offset)); 208 memcpy(buf, &w, sizeof w); 209 break; 210 case 4: 211 l = cpu_to_le32(ioread32(vp_dev->device + offset)); 212 memcpy(buf, &l, sizeof l); 213 break; 214 case 8: 215 l = cpu_to_le32(ioread32(vp_dev->device + offset)); 216 memcpy(buf, &l, sizeof l); 217 l = cpu_to_le32(ioread32(vp_dev->device + offset + sizeof l)); 218 memcpy(buf + sizeof l, &l, sizeof l); 219 break; 220 default: 221 BUG(); 222 } 223 } 224 225 /* the config->set() implementation. it's symmetric to the config->get() 226 * implementation */ 227 static void vp_set(struct virtio_device *vdev, unsigned offset, 228 const void *buf, unsigned len) 229 { 230 struct virtio_pci_device *vp_dev = to_vp_device(vdev); 231 u8 b; 232 __le16 w; 233 __le32 l; 234 235 BUG_ON(offset + len > vp_dev->device_len); 236 237 switch (len) { 238 case 1: 239 memcpy(&b, buf, sizeof b); 240 iowrite8(b, vp_dev->device + offset); 241 break; 242 case 2: 243 memcpy(&w, buf, sizeof w); 244 iowrite16(le16_to_cpu(w), vp_dev->device + offset); 245 break; 246 case 4: 247 memcpy(&l, buf, sizeof l); 248 iowrite32(le32_to_cpu(l), vp_dev->device + offset); 249 break; 250 case 8: 251 memcpy(&l, buf, sizeof l); 252 iowrite32(le32_to_cpu(l), vp_dev->device + offset); 253 memcpy(&l, buf + sizeof l, sizeof l); 254 iowrite32(le32_to_cpu(l), vp_dev->device + offset + sizeof l); 255 break; 256 default: 257 BUG(); 258 } 259 } 260 261 static u32 vp_generation(struct virtio_device *vdev) 262 { 263 struct virtio_pci_device *vp_dev = to_vp_device(vdev); 264 return vp_ioread8(&vp_dev->common->config_generation); 265 } 266 267 /* config->{get,set}_status() implementations */ 268 static u8 vp_get_status(struct virtio_device *vdev) 269 { 270 struct virtio_pci_device *vp_dev = to_vp_device(vdev); 271 return vp_ioread8(&vp_dev->common->device_status); 272 } 273 274 static void vp_set_status(struct virtio_device *vdev, u8 status) 275 { 276 struct virtio_pci_device *vp_dev = to_vp_device(vdev); 277 /* We should never be setting status to 0. */ 278 BUG_ON(status == 0); 279 vp_iowrite8(status, &vp_dev->common->device_status); 280 } 281 282 static void vp_reset(struct virtio_device *vdev) 283 { 284 struct virtio_pci_device *vp_dev = to_vp_device(vdev); 285 /* 0 status means a reset. */ 286 vp_iowrite8(0, &vp_dev->common->device_status); 287 /* After writing 0 to device_status, the driver MUST wait for a read of 288 * device_status to return 0 before reinitializing the device. 289 * This will flush out the status write, and flush in device writes, 290 * including MSI-X interrupts, if any. 291 */ 292 while (vp_ioread8(&vp_dev->common->device_status)) 293 msleep(1); 294 /* Flush pending VQ/configuration callbacks. */ 295 vp_synchronize_vectors(vdev); 296 } 297 298 static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector) 299 { 300 /* Setup the vector used for configuration events */ 301 vp_iowrite16(vector, &vp_dev->common->msix_config); 302 /* Verify we had enough resources to assign the vector */ 303 /* Will also flush the write out to device */ 304 return vp_ioread16(&vp_dev->common->msix_config); 305 } 306 307 static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev, 308 struct virtio_pci_vq_info *info, 309 unsigned index, 310 void (*callback)(struct virtqueue *vq), 311 const char *name, 312 bool ctx, 313 u16 msix_vec) 314 { 315 struct virtio_pci_common_cfg __iomem *cfg = vp_dev->common; 316 struct virtqueue *vq; 317 u16 num, off; 318 int err; 319 320 if (index >= vp_ioread16(&cfg->num_queues)) 321 return ERR_PTR(-ENOENT); 322 323 /* Select the queue we're interested in */ 324 vp_iowrite16(index, &cfg->queue_select); 325 326 /* Check if queue is either not available or already active. */ 327 num = vp_ioread16(&cfg->queue_size); 328 if (!num || vp_ioread16(&cfg->queue_enable)) 329 return ERR_PTR(-ENOENT); 330 331 if (num & (num - 1)) { 332 dev_warn(&vp_dev->pci_dev->dev, "bad queue size %u", num); 333 return ERR_PTR(-EINVAL); 334 } 335 336 /* get offset of notification word for this vq */ 337 off = vp_ioread16(&cfg->queue_notify_off); 338 339 info->msix_vector = msix_vec; 340 341 /* create the vring */ 342 vq = vring_create_virtqueue(index, num, 343 SMP_CACHE_BYTES, &vp_dev->vdev, 344 true, true, ctx, 345 vp_notify, callback, name); 346 if (!vq) 347 return ERR_PTR(-ENOMEM); 348 349 /* activate the queue */ 350 vp_iowrite16(virtqueue_get_vring_size(vq), &cfg->queue_size); 351 vp_iowrite64_twopart(virtqueue_get_desc_addr(vq), 352 &cfg->queue_desc_lo, &cfg->queue_desc_hi); 353 vp_iowrite64_twopart(virtqueue_get_avail_addr(vq), 354 &cfg->queue_avail_lo, &cfg->queue_avail_hi); 355 vp_iowrite64_twopart(virtqueue_get_used_addr(vq), 356 &cfg->queue_used_lo, &cfg->queue_used_hi); 357 358 if (vp_dev->notify_base) { 359 /* offset should not wrap */ 360 if ((u64)off * vp_dev->notify_offset_multiplier + 2 361 > vp_dev->notify_len) { 362 dev_warn(&vp_dev->pci_dev->dev, 363 "bad notification offset %u (x %u) " 364 "for queue %u > %zd", 365 off, vp_dev->notify_offset_multiplier, 366 index, vp_dev->notify_len); 367 err = -EINVAL; 368 goto err_map_notify; 369 } 370 vq->priv = (void __force *)vp_dev->notify_base + 371 off * vp_dev->notify_offset_multiplier; 372 } else { 373 vq->priv = (void __force *)map_capability(vp_dev->pci_dev, 374 vp_dev->notify_map_cap, 2, 2, 375 off * vp_dev->notify_offset_multiplier, 2, 376 NULL); 377 } 378 379 if (!vq->priv) { 380 err = -ENOMEM; 381 goto err_map_notify; 382 } 383 384 if (msix_vec != VIRTIO_MSI_NO_VECTOR) { 385 vp_iowrite16(msix_vec, &cfg->queue_msix_vector); 386 msix_vec = vp_ioread16(&cfg->queue_msix_vector); 387 if (msix_vec == VIRTIO_MSI_NO_VECTOR) { 388 err = -EBUSY; 389 goto err_assign_vector; 390 } 391 } 392 393 return vq; 394 395 err_assign_vector: 396 if (!vp_dev->notify_base) 397 pci_iounmap(vp_dev->pci_dev, (void __iomem __force *)vq->priv); 398 err_map_notify: 399 vring_del_virtqueue(vq); 400 return ERR_PTR(err); 401 } 402 403 static int vp_modern_find_vqs(struct virtio_device *vdev, unsigned nvqs, 404 struct virtqueue *vqs[], 405 vq_callback_t *callbacks[], 406 const char * const names[], const bool *ctx, 407 struct irq_affinity *desc) 408 { 409 struct virtio_pci_device *vp_dev = to_vp_device(vdev); 410 struct virtqueue *vq; 411 int rc = vp_find_vqs(vdev, nvqs, vqs, callbacks, names, ctx, desc); 412 413 if (rc) 414 return rc; 415 416 /* Select and activate all queues. Has to be done last: once we do 417 * this, there's no way to go back except reset. 418 */ 419 list_for_each_entry(vq, &vdev->vqs, list) { 420 vp_iowrite16(vq->index, &vp_dev->common->queue_select); 421 vp_iowrite16(1, &vp_dev->common->queue_enable); 422 } 423 424 return 0; 425 } 426 427 static void del_vq(struct virtio_pci_vq_info *info) 428 { 429 struct virtqueue *vq = info->vq; 430 struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); 431 432 vp_iowrite16(vq->index, &vp_dev->common->queue_select); 433 434 if (vp_dev->msix_enabled) { 435 vp_iowrite16(VIRTIO_MSI_NO_VECTOR, 436 &vp_dev->common->queue_msix_vector); 437 /* Flush the write out to device */ 438 vp_ioread16(&vp_dev->common->queue_msix_vector); 439 } 440 441 if (!vp_dev->notify_base) 442 pci_iounmap(vp_dev->pci_dev, (void __force __iomem *)vq->priv); 443 444 vring_del_virtqueue(vq); 445 } 446 447 static const struct virtio_config_ops virtio_pci_config_nodev_ops = { 448 .get = NULL, 449 .set = NULL, 450 .generation = vp_generation, 451 .get_status = vp_get_status, 452 .set_status = vp_set_status, 453 .reset = vp_reset, 454 .find_vqs = vp_modern_find_vqs, 455 .del_vqs = vp_del_vqs, 456 .get_features = vp_get_features, 457 .finalize_features = vp_finalize_features, 458 .bus_name = vp_bus_name, 459 .set_vq_affinity = vp_set_vq_affinity, 460 .get_vq_affinity = vp_get_vq_affinity, 461 }; 462 463 static const struct virtio_config_ops virtio_pci_config_ops = { 464 .get = vp_get, 465 .set = vp_set, 466 .generation = vp_generation, 467 .get_status = vp_get_status, 468 .set_status = vp_set_status, 469 .reset = vp_reset, 470 .find_vqs = vp_modern_find_vqs, 471 .del_vqs = vp_del_vqs, 472 .get_features = vp_get_features, 473 .finalize_features = vp_finalize_features, 474 .bus_name = vp_bus_name, 475 .set_vq_affinity = vp_set_vq_affinity, 476 .get_vq_affinity = vp_get_vq_affinity, 477 }; 478 479 /** 480 * virtio_pci_find_capability - walk capabilities to find device info. 481 * @dev: the pci device 482 * @cfg_type: the VIRTIO_PCI_CAP_* value we seek 483 * @ioresource_types: IORESOURCE_MEM and/or IORESOURCE_IO. 484 * 485 * Returns offset of the capability, or 0. 486 */ 487 static inline int virtio_pci_find_capability(struct pci_dev *dev, u8 cfg_type, 488 u32 ioresource_types, int *bars) 489 { 490 int pos; 491 492 for (pos = pci_find_capability(dev, PCI_CAP_ID_VNDR); 493 pos > 0; 494 pos = pci_find_next_capability(dev, pos, PCI_CAP_ID_VNDR)) { 495 u8 type, bar; 496 pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, 497 cfg_type), 498 &type); 499 pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, 500 bar), 501 &bar); 502 503 /* Ignore structures with reserved BAR values */ 504 if (bar > 0x5) 505 continue; 506 507 if (type == cfg_type) { 508 if (pci_resource_len(dev, bar) && 509 pci_resource_flags(dev, bar) & ioresource_types) { 510 *bars |= (1 << bar); 511 return pos; 512 } 513 } 514 } 515 return 0; 516 } 517 518 /* This is part of the ABI. Don't screw with it. */ 519 static inline void check_offsets(void) 520 { 521 /* Note: disk space was harmed in compilation of this function. */ 522 BUILD_BUG_ON(VIRTIO_PCI_CAP_VNDR != 523 offsetof(struct virtio_pci_cap, cap_vndr)); 524 BUILD_BUG_ON(VIRTIO_PCI_CAP_NEXT != 525 offsetof(struct virtio_pci_cap, cap_next)); 526 BUILD_BUG_ON(VIRTIO_PCI_CAP_LEN != 527 offsetof(struct virtio_pci_cap, cap_len)); 528 BUILD_BUG_ON(VIRTIO_PCI_CAP_CFG_TYPE != 529 offsetof(struct virtio_pci_cap, cfg_type)); 530 BUILD_BUG_ON(VIRTIO_PCI_CAP_BAR != 531 offsetof(struct virtio_pci_cap, bar)); 532 BUILD_BUG_ON(VIRTIO_PCI_CAP_OFFSET != 533 offsetof(struct virtio_pci_cap, offset)); 534 BUILD_BUG_ON(VIRTIO_PCI_CAP_LENGTH != 535 offsetof(struct virtio_pci_cap, length)); 536 BUILD_BUG_ON(VIRTIO_PCI_NOTIFY_CAP_MULT != 537 offsetof(struct virtio_pci_notify_cap, 538 notify_off_multiplier)); 539 BUILD_BUG_ON(VIRTIO_PCI_COMMON_DFSELECT != 540 offsetof(struct virtio_pci_common_cfg, 541 device_feature_select)); 542 BUILD_BUG_ON(VIRTIO_PCI_COMMON_DF != 543 offsetof(struct virtio_pci_common_cfg, device_feature)); 544 BUILD_BUG_ON(VIRTIO_PCI_COMMON_GFSELECT != 545 offsetof(struct virtio_pci_common_cfg, 546 guest_feature_select)); 547 BUILD_BUG_ON(VIRTIO_PCI_COMMON_GF != 548 offsetof(struct virtio_pci_common_cfg, guest_feature)); 549 BUILD_BUG_ON(VIRTIO_PCI_COMMON_MSIX != 550 offsetof(struct virtio_pci_common_cfg, msix_config)); 551 BUILD_BUG_ON(VIRTIO_PCI_COMMON_NUMQ != 552 offsetof(struct virtio_pci_common_cfg, num_queues)); 553 BUILD_BUG_ON(VIRTIO_PCI_COMMON_STATUS != 554 offsetof(struct virtio_pci_common_cfg, device_status)); 555 BUILD_BUG_ON(VIRTIO_PCI_COMMON_CFGGENERATION != 556 offsetof(struct virtio_pci_common_cfg, config_generation)); 557 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SELECT != 558 offsetof(struct virtio_pci_common_cfg, queue_select)); 559 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SIZE != 560 offsetof(struct virtio_pci_common_cfg, queue_size)); 561 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_MSIX != 562 offsetof(struct virtio_pci_common_cfg, queue_msix_vector)); 563 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_ENABLE != 564 offsetof(struct virtio_pci_common_cfg, queue_enable)); 565 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_NOFF != 566 offsetof(struct virtio_pci_common_cfg, queue_notify_off)); 567 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCLO != 568 offsetof(struct virtio_pci_common_cfg, queue_desc_lo)); 569 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCHI != 570 offsetof(struct virtio_pci_common_cfg, queue_desc_hi)); 571 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILLO != 572 offsetof(struct virtio_pci_common_cfg, queue_avail_lo)); 573 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILHI != 574 offsetof(struct virtio_pci_common_cfg, queue_avail_hi)); 575 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDLO != 576 offsetof(struct virtio_pci_common_cfg, queue_used_lo)); 577 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDHI != 578 offsetof(struct virtio_pci_common_cfg, queue_used_hi)); 579 } 580 581 /* the PCI probing function */ 582 int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev) 583 { 584 struct pci_dev *pci_dev = vp_dev->pci_dev; 585 int err, common, isr, notify, device; 586 u32 notify_length; 587 u32 notify_offset; 588 589 check_offsets(); 590 591 /* We only own devices >= 0x1000 and <= 0x107f: leave the rest. */ 592 if (pci_dev->device < 0x1000 || pci_dev->device > 0x107f) 593 return -ENODEV; 594 595 if (pci_dev->device < 0x1040) { 596 /* Transitional devices: use the PCI subsystem device id as 597 * virtio device id, same as legacy driver always did. 598 */ 599 vp_dev->vdev.id.device = pci_dev->subsystem_device; 600 } else { 601 /* Modern devices: simply use PCI device id, but start from 0x1040. */ 602 vp_dev->vdev.id.device = pci_dev->device - 0x1040; 603 } 604 vp_dev->vdev.id.vendor = pci_dev->subsystem_vendor; 605 606 /* check for a common config: if not, use legacy mode (bar 0). */ 607 common = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_COMMON_CFG, 608 IORESOURCE_IO | IORESOURCE_MEM, 609 &vp_dev->modern_bars); 610 if (!common) { 611 dev_info(&pci_dev->dev, 612 "virtio_pci: leaving for legacy driver\n"); 613 return -ENODEV; 614 } 615 616 /* If common is there, these should be too... */ 617 isr = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_ISR_CFG, 618 IORESOURCE_IO | IORESOURCE_MEM, 619 &vp_dev->modern_bars); 620 notify = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_NOTIFY_CFG, 621 IORESOURCE_IO | IORESOURCE_MEM, 622 &vp_dev->modern_bars); 623 if (!isr || !notify) { 624 dev_err(&pci_dev->dev, 625 "virtio_pci: missing capabilities %i/%i/%i\n", 626 common, isr, notify); 627 return -EINVAL; 628 } 629 630 err = dma_set_mask_and_coherent(&pci_dev->dev, DMA_BIT_MASK(64)); 631 if (err) 632 err = dma_set_mask_and_coherent(&pci_dev->dev, 633 DMA_BIT_MASK(32)); 634 if (err) 635 dev_warn(&pci_dev->dev, "Failed to enable 64-bit or 32-bit DMA. Trying to continue, but this might not work.\n"); 636 637 /* Device capability is only mandatory for devices that have 638 * device-specific configuration. 639 */ 640 device = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_DEVICE_CFG, 641 IORESOURCE_IO | IORESOURCE_MEM, 642 &vp_dev->modern_bars); 643 644 err = pci_request_selected_regions(pci_dev, vp_dev->modern_bars, 645 "virtio-pci-modern"); 646 if (err) 647 return err; 648 649 err = -EINVAL; 650 vp_dev->common = map_capability(pci_dev, common, 651 sizeof(struct virtio_pci_common_cfg), 4, 652 0, sizeof(struct virtio_pci_common_cfg), 653 NULL); 654 if (!vp_dev->common) 655 goto err_map_common; 656 vp_dev->isr = map_capability(pci_dev, isr, sizeof(u8), 1, 657 0, 1, 658 NULL); 659 if (!vp_dev->isr) 660 goto err_map_isr; 661 662 /* Read notify_off_multiplier from config space. */ 663 pci_read_config_dword(pci_dev, 664 notify + offsetof(struct virtio_pci_notify_cap, 665 notify_off_multiplier), 666 &vp_dev->notify_offset_multiplier); 667 /* Read notify length and offset from config space. */ 668 pci_read_config_dword(pci_dev, 669 notify + offsetof(struct virtio_pci_notify_cap, 670 cap.length), 671 ¬ify_length); 672 673 pci_read_config_dword(pci_dev, 674 notify + offsetof(struct virtio_pci_notify_cap, 675 cap.offset), 676 ¬ify_offset); 677 678 /* We don't know how many VQs we'll map, ahead of the time. 679 * If notify length is small, map it all now. 680 * Otherwise, map each VQ individually later. 681 */ 682 if ((u64)notify_length + (notify_offset % PAGE_SIZE) <= PAGE_SIZE) { 683 vp_dev->notify_base = map_capability(pci_dev, notify, 2, 2, 684 0, notify_length, 685 &vp_dev->notify_len); 686 if (!vp_dev->notify_base) 687 goto err_map_notify; 688 } else { 689 vp_dev->notify_map_cap = notify; 690 } 691 692 /* Again, we don't know how much we should map, but PAGE_SIZE 693 * is more than enough for all existing devices. 694 */ 695 if (device) { 696 vp_dev->device = map_capability(pci_dev, device, 0, 4, 697 0, PAGE_SIZE, 698 &vp_dev->device_len); 699 if (!vp_dev->device) 700 goto err_map_device; 701 702 vp_dev->vdev.config = &virtio_pci_config_ops; 703 } else { 704 vp_dev->vdev.config = &virtio_pci_config_nodev_ops; 705 } 706 707 vp_dev->config_vector = vp_config_vector; 708 vp_dev->setup_vq = setup_vq; 709 vp_dev->del_vq = del_vq; 710 711 return 0; 712 713 err_map_device: 714 if (vp_dev->notify_base) 715 pci_iounmap(pci_dev, vp_dev->notify_base); 716 err_map_notify: 717 pci_iounmap(pci_dev, vp_dev->isr); 718 err_map_isr: 719 pci_iounmap(pci_dev, vp_dev->common); 720 err_map_common: 721 return err; 722 } 723 724 void virtio_pci_modern_remove(struct virtio_pci_device *vp_dev) 725 { 726 struct pci_dev *pci_dev = vp_dev->pci_dev; 727 728 if (vp_dev->device) 729 pci_iounmap(pci_dev, vp_dev->device); 730 if (vp_dev->notify_base) 731 pci_iounmap(pci_dev, vp_dev->notify_base); 732 pci_iounmap(pci_dev, vp_dev->isr); 733 pci_iounmap(pci_dev, vp_dev->common); 734 pci_release_selected_regions(pci_dev, vp_dev->modern_bars); 735 } 736