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