1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * Copyright (c) 2023, NVIDIA CORPORATION & AFFILIATES. All rights reserved 4 */ 5 6#include <linux/device.h> 7#include <linux/module.h> 8#include <linux/mutex.h> 9#include <linux/pci.h> 10#include <linux/pm_runtime.h> 11#include <linux/types.h> 12#include <linux/uaccess.h> 13#include <linux/vfio.h> 14#include <linux/vfio_pci_core.h> 15#include <linux/virtio_pci.h> 16#include <linux/virtio_net.h> 17#include <linux/virtio_pci_admin.h> 18 19struct virtiovf_pci_core_device { 20 struct vfio_pci_core_device core_device; 21 u8 *bar0_virtual_buf; 22 /* synchronize access to the virtual buf */ 23 struct mutex bar_mutex; 24 void __iomem *notify_addr; 25 u64 notify_offset; 26 __le32 pci_base_addr_0; 27 __le16 pci_cmd; 28 u8 bar0_virtual_buf_size; 29 u8 notify_bar; 30}; 31 32static int 33virtiovf_issue_legacy_rw_cmd(struct virtiovf_pci_core_device *virtvdev, 34 loff_t pos, char __user *buf, 35 size_t count, bool read) 36{ 37 bool msix_enabled = 38 (virtvdev->core_device.irq_type == VFIO_PCI_MSIX_IRQ_INDEX); 39 struct pci_dev *pdev = virtvdev->core_device.pdev; 40 u8 *bar0_buf = virtvdev->bar0_virtual_buf; 41 bool common; 42 u8 offset; 43 int ret; 44 45 common = pos < VIRTIO_PCI_CONFIG_OFF(msix_enabled); 46 /* offset within the relevant configuration area */ 47 offset = common ? pos : pos - VIRTIO_PCI_CONFIG_OFF(msix_enabled); 48 mutex_lock(&virtvdev->bar_mutex); 49 if (read) { 50 if (common) 51 ret = virtio_pci_admin_legacy_common_io_read(pdev, offset, 52 count, bar0_buf + pos); 53 else 54 ret = virtio_pci_admin_legacy_device_io_read(pdev, offset, 55 count, bar0_buf + pos); 56 if (ret) 57 goto out; 58 if (copy_to_user(buf, bar0_buf + pos, count)) 59 ret = -EFAULT; 60 } else { 61 if (copy_from_user(bar0_buf + pos, buf, count)) { 62 ret = -EFAULT; 63 goto out; 64 } 65 66 if (common) 67 ret = virtio_pci_admin_legacy_common_io_write(pdev, offset, 68 count, bar0_buf + pos); 69 else 70 ret = virtio_pci_admin_legacy_device_io_write(pdev, offset, 71 count, bar0_buf + pos); 72 } 73out: 74 mutex_unlock(&virtvdev->bar_mutex); 75 return ret; 76} 77 78static int 79virtiovf_pci_bar0_rw(struct virtiovf_pci_core_device *virtvdev, 80 loff_t pos, char __user *buf, 81 size_t count, bool read) 82{ 83 struct vfio_pci_core_device *core_device = &virtvdev->core_device; 84 struct pci_dev *pdev = core_device->pdev; 85 u16 queue_notify; 86 int ret; 87 88 if (!(le16_to_cpu(virtvdev->pci_cmd) & PCI_COMMAND_IO)) 89 return -EIO; 90 91 if (pos + count > virtvdev->bar0_virtual_buf_size) 92 return -EINVAL; 93 94 ret = pm_runtime_resume_and_get(&pdev->dev); 95 if (ret) { 96 pci_info_ratelimited(pdev, "runtime resume failed %d\n", ret); 97 return -EIO; 98 } 99 100 switch (pos) { 101 case VIRTIO_PCI_QUEUE_NOTIFY: 102 if (count != sizeof(queue_notify)) { 103 ret = -EINVAL; 104 goto end; 105 } 106 if (read) { 107 ret = vfio_pci_core_ioread16(core_device, true, &queue_notify, 108 virtvdev->notify_addr); 109 if (ret) 110 goto end; 111 if (copy_to_user(buf, &queue_notify, 112 sizeof(queue_notify))) { 113 ret = -EFAULT; 114 goto end; 115 } 116 } else { 117 if (copy_from_user(&queue_notify, buf, count)) { 118 ret = -EFAULT; 119 goto end; 120 } 121 ret = vfio_pci_core_iowrite16(core_device, true, queue_notify, 122 virtvdev->notify_addr); 123 } 124 break; 125 default: 126 ret = virtiovf_issue_legacy_rw_cmd(virtvdev, pos, buf, count, 127 read); 128 } 129 130end: 131 pm_runtime_put(&pdev->dev); 132 return ret ? ret : count; 133} 134 135static ssize_t virtiovf_pci_read_config(struct vfio_device *core_vdev, 136 char __user *buf, size_t count, 137 loff_t *ppos) 138{ 139 struct virtiovf_pci_core_device *virtvdev = container_of( 140 core_vdev, struct virtiovf_pci_core_device, core_device.vdev); 141 loff_t pos = *ppos & VFIO_PCI_OFFSET_MASK; 142 size_t register_offset; 143 loff_t copy_offset; 144 size_t copy_count; 145 __le32 val32; 146 __le16 val16; 147 u8 val8; 148 int ret; 149 150 ret = vfio_pci_core_read(core_vdev, buf, count, ppos); 151 if (ret < 0) 152 return ret; 153 154 if (vfio_pci_core_range_intersect_range(pos, count, PCI_DEVICE_ID, 155 sizeof(val16), ©_offset, 156 ©_count, ®ister_offset)) { 157 val16 = cpu_to_le16(VIRTIO_TRANS_ID_NET); 158 if (copy_to_user(buf + copy_offset, (void *)&val16 + register_offset, copy_count)) 159 return -EFAULT; 160 } 161 162 if ((le16_to_cpu(virtvdev->pci_cmd) & PCI_COMMAND_IO) && 163 vfio_pci_core_range_intersect_range(pos, count, PCI_COMMAND, 164 sizeof(val16), ©_offset, 165 ©_count, ®ister_offset)) { 166 if (copy_from_user((void *)&val16 + register_offset, buf + copy_offset, 167 copy_count)) 168 return -EFAULT; 169 val16 |= cpu_to_le16(PCI_COMMAND_IO); 170 if (copy_to_user(buf + copy_offset, (void *)&val16 + register_offset, 171 copy_count)) 172 return -EFAULT; 173 } 174 175 if (vfio_pci_core_range_intersect_range(pos, count, PCI_REVISION_ID, 176 sizeof(val8), ©_offset, 177 ©_count, ®ister_offset)) { 178 /* Transional needs to have revision 0 */ 179 val8 = 0; 180 if (copy_to_user(buf + copy_offset, &val8, copy_count)) 181 return -EFAULT; 182 } 183 184 if (vfio_pci_core_range_intersect_range(pos, count, PCI_BASE_ADDRESS_0, 185 sizeof(val32), ©_offset, 186 ©_count, ®ister_offset)) { 187 u32 bar_mask = ~(virtvdev->bar0_virtual_buf_size - 1); 188 u32 pci_base_addr_0 = le32_to_cpu(virtvdev->pci_base_addr_0); 189 190 val32 = cpu_to_le32((pci_base_addr_0 & bar_mask) | PCI_BASE_ADDRESS_SPACE_IO); 191 if (copy_to_user(buf + copy_offset, (void *)&val32 + register_offset, copy_count)) 192 return -EFAULT; 193 } 194 195 if (vfio_pci_core_range_intersect_range(pos, count, PCI_SUBSYSTEM_ID, 196 sizeof(val16), ©_offset, 197 ©_count, ®ister_offset)) { 198 /* 199 * Transitional devices use the PCI subsystem device id as 200 * virtio device id, same as legacy driver always did. 201 */ 202 val16 = cpu_to_le16(VIRTIO_ID_NET); 203 if (copy_to_user(buf + copy_offset, (void *)&val16 + register_offset, 204 copy_count)) 205 return -EFAULT; 206 } 207 208 if (vfio_pci_core_range_intersect_range(pos, count, PCI_SUBSYSTEM_VENDOR_ID, 209 sizeof(val16), ©_offset, 210 ©_count, ®ister_offset)) { 211 val16 = cpu_to_le16(PCI_VENDOR_ID_REDHAT_QUMRANET); 212 if (copy_to_user(buf + copy_offset, (void *)&val16 + register_offset, 213 copy_count)) 214 return -EFAULT; 215 } 216 217 return count; 218} 219 220static ssize_t 221virtiovf_pci_core_read(struct vfio_device *core_vdev, char __user *buf, 222 size_t count, loff_t *ppos) 223{ 224 struct virtiovf_pci_core_device *virtvdev = container_of( 225 core_vdev, struct virtiovf_pci_core_device, core_device.vdev); 226 unsigned int index = VFIO_PCI_OFFSET_TO_INDEX(*ppos); 227 loff_t pos = *ppos & VFIO_PCI_OFFSET_MASK; 228 229 if (!count) 230 return 0; 231 232 if (index == VFIO_PCI_CONFIG_REGION_INDEX) 233 return virtiovf_pci_read_config(core_vdev, buf, count, ppos); 234 235 if (index == VFIO_PCI_BAR0_REGION_INDEX) 236 return virtiovf_pci_bar0_rw(virtvdev, pos, buf, count, true); 237 238 return vfio_pci_core_read(core_vdev, buf, count, ppos); 239} 240 241static ssize_t virtiovf_pci_write_config(struct vfio_device *core_vdev, 242 const char __user *buf, size_t count, 243 loff_t *ppos) 244{ 245 struct virtiovf_pci_core_device *virtvdev = container_of( 246 core_vdev, struct virtiovf_pci_core_device, core_device.vdev); 247 loff_t pos = *ppos & VFIO_PCI_OFFSET_MASK; 248 size_t register_offset; 249 loff_t copy_offset; 250 size_t copy_count; 251 252 if (vfio_pci_core_range_intersect_range(pos, count, PCI_COMMAND, 253 sizeof(virtvdev->pci_cmd), 254 ©_offset, ©_count, 255 ®ister_offset)) { 256 if (copy_from_user((void *)&virtvdev->pci_cmd + register_offset, 257 buf + copy_offset, 258 copy_count)) 259 return -EFAULT; 260 } 261 262 if (vfio_pci_core_range_intersect_range(pos, count, PCI_BASE_ADDRESS_0, 263 sizeof(virtvdev->pci_base_addr_0), 264 ©_offset, ©_count, 265 ®ister_offset)) { 266 if (copy_from_user((void *)&virtvdev->pci_base_addr_0 + register_offset, 267 buf + copy_offset, 268 copy_count)) 269 return -EFAULT; 270 } 271 272 return vfio_pci_core_write(core_vdev, buf, count, ppos); 273} 274 275static ssize_t 276virtiovf_pci_core_write(struct vfio_device *core_vdev, const char __user *buf, 277 size_t count, loff_t *ppos) 278{ 279 struct virtiovf_pci_core_device *virtvdev = container_of( 280 core_vdev, struct virtiovf_pci_core_device, core_device.vdev); 281 unsigned int index = VFIO_PCI_OFFSET_TO_INDEX(*ppos); 282 loff_t pos = *ppos & VFIO_PCI_OFFSET_MASK; 283 284 if (!count) 285 return 0; 286 287 if (index == VFIO_PCI_CONFIG_REGION_INDEX) 288 return virtiovf_pci_write_config(core_vdev, buf, count, ppos); 289 290 if (index == VFIO_PCI_BAR0_REGION_INDEX) 291 return virtiovf_pci_bar0_rw(virtvdev, pos, (char __user *)buf, count, false); 292 293 return vfio_pci_core_write(core_vdev, buf, count, ppos); 294} 295 296static int 297virtiovf_pci_ioctl_get_region_info(struct vfio_device *core_vdev, 298 unsigned int cmd, unsigned long arg) 299{ 300 struct virtiovf_pci_core_device *virtvdev = container_of( 301 core_vdev, struct virtiovf_pci_core_device, core_device.vdev); 302 unsigned long minsz = offsetofend(struct vfio_region_info, offset); 303 void __user *uarg = (void __user *)arg; 304 struct vfio_region_info info = {}; 305 306 if (copy_from_user(&info, uarg, minsz)) 307 return -EFAULT; 308 309 if (info.argsz < minsz) 310 return -EINVAL; 311 312 switch (info.index) { 313 case VFIO_PCI_BAR0_REGION_INDEX: 314 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index); 315 info.size = virtvdev->bar0_virtual_buf_size; 316 info.flags = VFIO_REGION_INFO_FLAG_READ | 317 VFIO_REGION_INFO_FLAG_WRITE; 318 return copy_to_user(uarg, &info, minsz) ? -EFAULT : 0; 319 default: 320 return vfio_pci_core_ioctl(core_vdev, cmd, arg); 321 } 322} 323 324static long 325virtiovf_vfio_pci_core_ioctl(struct vfio_device *core_vdev, unsigned int cmd, 326 unsigned long arg) 327{ 328 switch (cmd) { 329 case VFIO_DEVICE_GET_REGION_INFO: 330 return virtiovf_pci_ioctl_get_region_info(core_vdev, cmd, arg); 331 default: 332 return vfio_pci_core_ioctl(core_vdev, cmd, arg); 333 } 334} 335 336static int 337virtiovf_set_notify_addr(struct virtiovf_pci_core_device *virtvdev) 338{ 339 struct vfio_pci_core_device *core_device = &virtvdev->core_device; 340 int ret; 341 342 /* 343 * Setup the BAR where the 'notify' exists to be used by vfio as well 344 * This will let us mmap it only once and use it when needed. 345 */ 346 ret = vfio_pci_core_setup_barmap(core_device, 347 virtvdev->notify_bar); 348 if (ret) 349 return ret; 350 351 virtvdev->notify_addr = core_device->barmap[virtvdev->notify_bar] + 352 virtvdev->notify_offset; 353 return 0; 354} 355 356static int virtiovf_pci_open_device(struct vfio_device *core_vdev) 357{ 358 struct virtiovf_pci_core_device *virtvdev = container_of( 359 core_vdev, struct virtiovf_pci_core_device, core_device.vdev); 360 struct vfio_pci_core_device *vdev = &virtvdev->core_device; 361 int ret; 362 363 ret = vfio_pci_core_enable(vdev); 364 if (ret) 365 return ret; 366 367 if (virtvdev->bar0_virtual_buf) { 368 /* 369 * Upon close_device() the vfio_pci_core_disable() is called 370 * and will close all the previous mmaps, so it seems that the 371 * valid life cycle for the 'notify' addr is per open/close. 372 */ 373 ret = virtiovf_set_notify_addr(virtvdev); 374 if (ret) { 375 vfio_pci_core_disable(vdev); 376 return ret; 377 } 378 } 379 380 vfio_pci_core_finish_enable(vdev); 381 return 0; 382} 383 384static int virtiovf_get_device_config_size(unsigned short device) 385{ 386 /* Network card */ 387 return offsetofend(struct virtio_net_config, status); 388} 389 390static int virtiovf_read_notify_info(struct virtiovf_pci_core_device *virtvdev) 391{ 392 u64 offset; 393 int ret; 394 u8 bar; 395 396 ret = virtio_pci_admin_legacy_io_notify_info(virtvdev->core_device.pdev, 397 VIRTIO_ADMIN_CMD_NOTIFY_INFO_FLAGS_OWNER_MEM, 398 &bar, &offset); 399 if (ret) 400 return ret; 401 402 virtvdev->notify_bar = bar; 403 virtvdev->notify_offset = offset; 404 return 0; 405} 406 407static int virtiovf_pci_init_device(struct vfio_device *core_vdev) 408{ 409 struct virtiovf_pci_core_device *virtvdev = container_of( 410 core_vdev, struct virtiovf_pci_core_device, core_device.vdev); 411 struct pci_dev *pdev; 412 int ret; 413 414 ret = vfio_pci_core_init_dev(core_vdev); 415 if (ret) 416 return ret; 417 418 pdev = virtvdev->core_device.pdev; 419 ret = virtiovf_read_notify_info(virtvdev); 420 if (ret) 421 return ret; 422 423 virtvdev->bar0_virtual_buf_size = VIRTIO_PCI_CONFIG_OFF(true) + 424 virtiovf_get_device_config_size(pdev->device); 425 BUILD_BUG_ON(!is_power_of_2(virtvdev->bar0_virtual_buf_size)); 426 virtvdev->bar0_virtual_buf = kzalloc(virtvdev->bar0_virtual_buf_size, 427 GFP_KERNEL); 428 if (!virtvdev->bar0_virtual_buf) 429 return -ENOMEM; 430 mutex_init(&virtvdev->bar_mutex); 431 return 0; 432} 433 434static void virtiovf_pci_core_release_dev(struct vfio_device *core_vdev) 435{ 436 struct virtiovf_pci_core_device *virtvdev = container_of( 437 core_vdev, struct virtiovf_pci_core_device, core_device.vdev); 438 439 kfree(virtvdev->bar0_virtual_buf); 440 vfio_pci_core_release_dev(core_vdev); 441} 442 443static const struct vfio_device_ops virtiovf_vfio_pci_tran_ops = { 444 .name = "virtio-vfio-pci-trans", 445 .init = virtiovf_pci_init_device, 446 .release = virtiovf_pci_core_release_dev, 447 .open_device = virtiovf_pci_open_device, 448 .close_device = vfio_pci_core_close_device, 449 .ioctl = virtiovf_vfio_pci_core_ioctl, 450 .device_feature = vfio_pci_core_ioctl_feature, 451 .read = virtiovf_pci_core_read, 452 .write = virtiovf_pci_core_write, 453 .mmap = vfio_pci_core_mmap, 454 .request = vfio_pci_core_request, 455 .match = vfio_pci_core_match, 456 .bind_iommufd = vfio_iommufd_physical_bind, 457 .unbind_iommufd = vfio_iommufd_physical_unbind, 458 .attach_ioas = vfio_iommufd_physical_attach_ioas, 459 .detach_ioas = vfio_iommufd_physical_detach_ioas, 460}; 461 462static const struct vfio_device_ops virtiovf_vfio_pci_ops = { 463 .name = "virtio-vfio-pci", 464 .init = vfio_pci_core_init_dev, 465 .release = vfio_pci_core_release_dev, 466 .open_device = virtiovf_pci_open_device, 467 .close_device = vfio_pci_core_close_device, 468 .ioctl = vfio_pci_core_ioctl, 469 .device_feature = vfio_pci_core_ioctl_feature, 470 .read = vfio_pci_core_read, 471 .write = vfio_pci_core_write, 472 .mmap = vfio_pci_core_mmap, 473 .request = vfio_pci_core_request, 474 .match = vfio_pci_core_match, 475 .bind_iommufd = vfio_iommufd_physical_bind, 476 .unbind_iommufd = vfio_iommufd_physical_unbind, 477 .attach_ioas = vfio_iommufd_physical_attach_ioas, 478 .detach_ioas = vfio_iommufd_physical_detach_ioas, 479}; 480 481static bool virtiovf_bar0_exists(struct pci_dev *pdev) 482{ 483 struct resource *res = pdev->resource; 484 485 return res->flags; 486} 487 488static int virtiovf_pci_probe(struct pci_dev *pdev, 489 const struct pci_device_id *id) 490{ 491 const struct vfio_device_ops *ops = &virtiovf_vfio_pci_ops; 492 struct virtiovf_pci_core_device *virtvdev; 493 int ret; 494 495 if (pdev->is_virtfn && virtio_pci_admin_has_legacy_io(pdev) && 496 !virtiovf_bar0_exists(pdev)) 497 ops = &virtiovf_vfio_pci_tran_ops; 498 499 virtvdev = vfio_alloc_device(virtiovf_pci_core_device, core_device.vdev, 500 &pdev->dev, ops); 501 if (IS_ERR(virtvdev)) 502 return PTR_ERR(virtvdev); 503 504 dev_set_drvdata(&pdev->dev, &virtvdev->core_device); 505 ret = vfio_pci_core_register_device(&virtvdev->core_device); 506 if (ret) 507 goto out; 508 return 0; 509out: 510 vfio_put_device(&virtvdev->core_device.vdev); 511 return ret; 512} 513 514static void virtiovf_pci_remove(struct pci_dev *pdev) 515{ 516 struct virtiovf_pci_core_device *virtvdev = dev_get_drvdata(&pdev->dev); 517 518 vfio_pci_core_unregister_device(&virtvdev->core_device); 519 vfio_put_device(&virtvdev->core_device.vdev); 520} 521 522static const struct pci_device_id virtiovf_pci_table[] = { 523 /* Only virtio-net is supported/tested so far */ 524 { PCI_DRIVER_OVERRIDE_DEVICE_VFIO(PCI_VENDOR_ID_REDHAT_QUMRANET, 0x1041) }, 525 {} 526}; 527 528MODULE_DEVICE_TABLE(pci, virtiovf_pci_table); 529 530static void virtiovf_pci_aer_reset_done(struct pci_dev *pdev) 531{ 532 struct virtiovf_pci_core_device *virtvdev = dev_get_drvdata(&pdev->dev); 533 534 virtvdev->pci_cmd = 0; 535} 536 537static const struct pci_error_handlers virtiovf_err_handlers = { 538 .reset_done = virtiovf_pci_aer_reset_done, 539 .error_detected = vfio_pci_core_aer_err_detected, 540}; 541 542static struct pci_driver virtiovf_pci_driver = { 543 .name = KBUILD_MODNAME, 544 .id_table = virtiovf_pci_table, 545 .probe = virtiovf_pci_probe, 546 .remove = virtiovf_pci_remove, 547 .err_handler = &virtiovf_err_handlers, 548 .driver_managed_dma = true, 549}; 550 551module_pci_driver(virtiovf_pci_driver); 552 553MODULE_LICENSE("GPL"); 554MODULE_AUTHOR("Yishai Hadas <yishaih@nvidia.com>"); 555MODULE_DESCRIPTION( 556 "VIRTIO VFIO PCI - User Level meta-driver for VIRTIO NET devices"); 557