1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2012 Red Hat, Inc. All rights reserved.
4 * Author: Alex Williamson <alex.williamson@redhat.com>
5 *
6 * Derived from original vfio:
7 * Copyright 2010 Cisco Systems, Inc. All rights reserved.
8 * Author: Tom Lyon, pugs@cisco.com
9 */
10
11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12
13 #include <linux/aperture.h>
14 #include <linux/device.h>
15 #include <linux/eventfd.h>
16 #include <linux/file.h>
17 #include <linux/interrupt.h>
18 #include <linux/iommu.h>
19 #include <linux/module.h>
20 #include <linux/mutex.h>
21 #include <linux/notifier.h>
22 #include <linux/pci.h>
23 #include <linux/pfn_t.h>
24 #include <linux/pm_runtime.h>
25 #include <linux/slab.h>
26 #include <linux/types.h>
27 #include <linux/uaccess.h>
28 #include <linux/vgaarb.h>
29 #include <linux/nospec.h>
30 #include <linux/sched/mm.h>
31 #include <linux/iommufd.h>
32 #if IS_ENABLED(CONFIG_EEH)
33 #include <asm/eeh.h>
34 #endif
35
36 #include "vfio_pci_priv.h"
37
38 #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
39 #define DRIVER_DESC "core driver for VFIO based PCI devices"
40
41 static bool nointxmask;
42 static bool disable_vga;
43 static bool disable_idle_d3;
44
45 /* List of PF's that vfio_pci_core_sriov_configure() has been called on */
46 static DEFINE_MUTEX(vfio_pci_sriov_pfs_mutex);
47 static LIST_HEAD(vfio_pci_sriov_pfs);
48
49 struct vfio_pci_dummy_resource {
50 struct resource resource;
51 int index;
52 struct list_head res_next;
53 };
54
55 struct vfio_pci_vf_token {
56 struct mutex lock;
57 uuid_t uuid;
58 int users;
59 };
60
vfio_vga_disabled(void)61 static inline bool vfio_vga_disabled(void)
62 {
63 #ifdef CONFIG_VFIO_PCI_VGA
64 return disable_vga;
65 #else
66 return true;
67 #endif
68 }
69
70 /*
71 * Our VGA arbiter participation is limited since we don't know anything
72 * about the device itself. However, if the device is the only VGA device
73 * downstream of a bridge and VFIO VGA support is disabled, then we can
74 * safely return legacy VGA IO and memory as not decoded since the user
75 * has no way to get to it and routing can be disabled externally at the
76 * bridge.
77 */
vfio_pci_set_decode(struct pci_dev * pdev,bool single_vga)78 static unsigned int vfio_pci_set_decode(struct pci_dev *pdev, bool single_vga)
79 {
80 struct pci_dev *tmp = NULL;
81 unsigned char max_busnr;
82 unsigned int decodes;
83
84 if (single_vga || !vfio_vga_disabled() || pci_is_root_bus(pdev->bus))
85 return VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM |
86 VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM;
87
88 max_busnr = pci_bus_max_busnr(pdev->bus);
89 decodes = VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM;
90
91 while ((tmp = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, tmp)) != NULL) {
92 if (tmp == pdev ||
93 pci_domain_nr(tmp->bus) != pci_domain_nr(pdev->bus) ||
94 pci_is_root_bus(tmp->bus))
95 continue;
96
97 if (tmp->bus->number >= pdev->bus->number &&
98 tmp->bus->number <= max_busnr) {
99 pci_dev_put(tmp);
100 decodes |= VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM;
101 break;
102 }
103 }
104
105 return decodes;
106 }
107
vfio_pci_probe_mmaps(struct vfio_pci_core_device * vdev)108 static void vfio_pci_probe_mmaps(struct vfio_pci_core_device *vdev)
109 {
110 struct resource *res;
111 int i;
112 struct vfio_pci_dummy_resource *dummy_res;
113
114 for (i = 0; i < PCI_STD_NUM_BARS; i++) {
115 int bar = i + PCI_STD_RESOURCES;
116
117 res = &vdev->pdev->resource[bar];
118
119 if (!IS_ENABLED(CONFIG_VFIO_PCI_MMAP))
120 goto no_mmap;
121
122 if (!(res->flags & IORESOURCE_MEM))
123 goto no_mmap;
124
125 /*
126 * The PCI core shouldn't set up a resource with a
127 * type but zero size. But there may be bugs that
128 * cause us to do that.
129 */
130 if (!resource_size(res))
131 goto no_mmap;
132
133 if (resource_size(res) >= PAGE_SIZE) {
134 vdev->bar_mmap_supported[bar] = true;
135 continue;
136 }
137
138 if (!(res->start & ~PAGE_MASK)) {
139 /*
140 * Add a dummy resource to reserve the remainder
141 * of the exclusive page in case that hot-add
142 * device's bar is assigned into it.
143 */
144 dummy_res =
145 kzalloc(sizeof(*dummy_res), GFP_KERNEL_ACCOUNT);
146 if (dummy_res == NULL)
147 goto no_mmap;
148
149 dummy_res->resource.name = "vfio sub-page reserved";
150 dummy_res->resource.start = res->end + 1;
151 dummy_res->resource.end = res->start + PAGE_SIZE - 1;
152 dummy_res->resource.flags = res->flags;
153 if (request_resource(res->parent,
154 &dummy_res->resource)) {
155 kfree(dummy_res);
156 goto no_mmap;
157 }
158 dummy_res->index = bar;
159 list_add(&dummy_res->res_next,
160 &vdev->dummy_resources_list);
161 vdev->bar_mmap_supported[bar] = true;
162 continue;
163 }
164 /*
165 * Here we don't handle the case when the BAR is not page
166 * aligned because we can't expect the BAR will be
167 * assigned into the same location in a page in guest
168 * when we passthrough the BAR. And it's hard to access
169 * this BAR in userspace because we have no way to get
170 * the BAR's location in a page.
171 */
172 no_mmap:
173 vdev->bar_mmap_supported[bar] = false;
174 }
175 }
176
177 struct vfio_pci_group_info;
178 static void vfio_pci_dev_set_try_reset(struct vfio_device_set *dev_set);
179 static int vfio_pci_dev_set_hot_reset(struct vfio_device_set *dev_set,
180 struct vfio_pci_group_info *groups,
181 struct iommufd_ctx *iommufd_ctx);
182
183 /*
184 * INTx masking requires the ability to disable INTx signaling via PCI_COMMAND
185 * _and_ the ability detect when the device is asserting INTx via PCI_STATUS.
186 * If a device implements the former but not the latter we would typically
187 * expect broken_intx_masking be set and require an exclusive interrupt.
188 * However since we do have control of the device's ability to assert INTx,
189 * we can instead pretend that the device does not implement INTx, virtualizing
190 * the pin register to report zero and maintaining DisINTx set on the host.
191 */
vfio_pci_nointx(struct pci_dev * pdev)192 static bool vfio_pci_nointx(struct pci_dev *pdev)
193 {
194 switch (pdev->vendor) {
195 case PCI_VENDOR_ID_INTEL:
196 switch (pdev->device) {
197 /* All i40e (XL710/X710/XXV710) 10/20/25/40GbE NICs */
198 case 0x1572:
199 case 0x1574:
200 case 0x1580 ... 0x1581:
201 case 0x1583 ... 0x158b:
202 case 0x37d0 ... 0x37d2:
203 /* X550 */
204 case 0x1563:
205 return true;
206 default:
207 return false;
208 }
209 }
210
211 return false;
212 }
213
vfio_pci_probe_power_state(struct vfio_pci_core_device * vdev)214 static void vfio_pci_probe_power_state(struct vfio_pci_core_device *vdev)
215 {
216 struct pci_dev *pdev = vdev->pdev;
217 u16 pmcsr;
218
219 if (!pdev->pm_cap)
220 return;
221
222 pci_read_config_word(pdev, pdev->pm_cap + PCI_PM_CTRL, &pmcsr);
223
224 vdev->needs_pm_restore = !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET);
225 }
226
227 /*
228 * pci_set_power_state() wrapper handling devices which perform a soft reset on
229 * D3->D0 transition. Save state prior to D0/1/2->D3, stash it on the vdev,
230 * restore when returned to D0. Saved separately from pci_saved_state for use
231 * by PM capability emulation and separately from pci_dev internal saved state
232 * to avoid it being overwritten and consumed around other resets.
233 */
vfio_pci_set_power_state(struct vfio_pci_core_device * vdev,pci_power_t state)234 int vfio_pci_set_power_state(struct vfio_pci_core_device *vdev, pci_power_t state)
235 {
236 struct pci_dev *pdev = vdev->pdev;
237 bool needs_restore = false, needs_save = false;
238 int ret;
239
240 /* Prevent changing power state for PFs with VFs enabled */
241 if (pci_num_vf(pdev) && state > PCI_D0)
242 return -EBUSY;
243
244 if (vdev->needs_pm_restore) {
245 if (pdev->current_state < PCI_D3hot && state >= PCI_D3hot) {
246 pci_save_state(pdev);
247 needs_save = true;
248 }
249
250 if (pdev->current_state >= PCI_D3hot && state <= PCI_D0)
251 needs_restore = true;
252 }
253
254 ret = pci_set_power_state(pdev, state);
255
256 if (!ret) {
257 /* D3 might be unsupported via quirk, skip unless in D3 */
258 if (needs_save && pdev->current_state >= PCI_D3hot) {
259 /*
260 * The current PCI state will be saved locally in
261 * 'pm_save' during the D3hot transition. When the
262 * device state is changed to D0 again with the current
263 * function, then pci_store_saved_state() will restore
264 * the state and will free the memory pointed by
265 * 'pm_save'. There are few cases where the PCI power
266 * state can be changed to D0 without the involvement
267 * of the driver. For these cases, free the earlier
268 * allocated memory first before overwriting 'pm_save'
269 * to prevent the memory leak.
270 */
271 kfree(vdev->pm_save);
272 vdev->pm_save = pci_store_saved_state(pdev);
273 } else if (needs_restore) {
274 pci_load_and_free_saved_state(pdev, &vdev->pm_save);
275 pci_restore_state(pdev);
276 }
277 }
278
279 return ret;
280 }
281
vfio_pci_runtime_pm_entry(struct vfio_pci_core_device * vdev,struct eventfd_ctx * efdctx)282 static int vfio_pci_runtime_pm_entry(struct vfio_pci_core_device *vdev,
283 struct eventfd_ctx *efdctx)
284 {
285 /*
286 * The vdev power related flags are protected with 'memory_lock'
287 * semaphore.
288 */
289 vfio_pci_zap_and_down_write_memory_lock(vdev);
290 if (vdev->pm_runtime_engaged) {
291 up_write(&vdev->memory_lock);
292 return -EINVAL;
293 }
294
295 vdev->pm_runtime_engaged = true;
296 vdev->pm_wake_eventfd_ctx = efdctx;
297 pm_runtime_put_noidle(&vdev->pdev->dev);
298 up_write(&vdev->memory_lock);
299
300 return 0;
301 }
302
vfio_pci_core_pm_entry(struct vfio_device * device,u32 flags,void __user * arg,size_t argsz)303 static int vfio_pci_core_pm_entry(struct vfio_device *device, u32 flags,
304 void __user *arg, size_t argsz)
305 {
306 struct vfio_pci_core_device *vdev =
307 container_of(device, struct vfio_pci_core_device, vdev);
308 int ret;
309
310 ret = vfio_check_feature(flags, argsz, VFIO_DEVICE_FEATURE_SET, 0);
311 if (ret != 1)
312 return ret;
313
314 /*
315 * Inside vfio_pci_runtime_pm_entry(), only the runtime PM usage count
316 * will be decremented. The pm_runtime_put() will be invoked again
317 * while returning from the ioctl and then the device can go into
318 * runtime suspended state.
319 */
320 return vfio_pci_runtime_pm_entry(vdev, NULL);
321 }
322
vfio_pci_core_pm_entry_with_wakeup(struct vfio_device * device,u32 flags,struct vfio_device_low_power_entry_with_wakeup __user * arg,size_t argsz)323 static int vfio_pci_core_pm_entry_with_wakeup(
324 struct vfio_device *device, u32 flags,
325 struct vfio_device_low_power_entry_with_wakeup __user *arg,
326 size_t argsz)
327 {
328 struct vfio_pci_core_device *vdev =
329 container_of(device, struct vfio_pci_core_device, vdev);
330 struct vfio_device_low_power_entry_with_wakeup entry;
331 struct eventfd_ctx *efdctx;
332 int ret;
333
334 ret = vfio_check_feature(flags, argsz, VFIO_DEVICE_FEATURE_SET,
335 sizeof(entry));
336 if (ret != 1)
337 return ret;
338
339 if (copy_from_user(&entry, arg, sizeof(entry)))
340 return -EFAULT;
341
342 if (entry.wakeup_eventfd < 0)
343 return -EINVAL;
344
345 efdctx = eventfd_ctx_fdget(entry.wakeup_eventfd);
346 if (IS_ERR(efdctx))
347 return PTR_ERR(efdctx);
348
349 ret = vfio_pci_runtime_pm_entry(vdev, efdctx);
350 if (ret)
351 eventfd_ctx_put(efdctx);
352
353 return ret;
354 }
355
__vfio_pci_runtime_pm_exit(struct vfio_pci_core_device * vdev)356 static void __vfio_pci_runtime_pm_exit(struct vfio_pci_core_device *vdev)
357 {
358 if (vdev->pm_runtime_engaged) {
359 vdev->pm_runtime_engaged = false;
360 pm_runtime_get_noresume(&vdev->pdev->dev);
361
362 if (vdev->pm_wake_eventfd_ctx) {
363 eventfd_ctx_put(vdev->pm_wake_eventfd_ctx);
364 vdev->pm_wake_eventfd_ctx = NULL;
365 }
366 }
367 }
368
vfio_pci_runtime_pm_exit(struct vfio_pci_core_device * vdev)369 static void vfio_pci_runtime_pm_exit(struct vfio_pci_core_device *vdev)
370 {
371 /*
372 * The vdev power related flags are protected with 'memory_lock'
373 * semaphore.
374 */
375 down_write(&vdev->memory_lock);
376 __vfio_pci_runtime_pm_exit(vdev);
377 up_write(&vdev->memory_lock);
378 }
379
vfio_pci_core_pm_exit(struct vfio_device * device,u32 flags,void __user * arg,size_t argsz)380 static int vfio_pci_core_pm_exit(struct vfio_device *device, u32 flags,
381 void __user *arg, size_t argsz)
382 {
383 struct vfio_pci_core_device *vdev =
384 container_of(device, struct vfio_pci_core_device, vdev);
385 int ret;
386
387 ret = vfio_check_feature(flags, argsz, VFIO_DEVICE_FEATURE_SET, 0);
388 if (ret != 1)
389 return ret;
390
391 /*
392 * The device is always in the active state here due to pm wrappers
393 * around ioctls. If the device had entered a low power state and
394 * pm_wake_eventfd_ctx is valid, vfio_pci_core_runtime_resume() has
395 * already signaled the eventfd and exited low power mode itself.
396 * pm_runtime_engaged protects the redundant call here.
397 */
398 vfio_pci_runtime_pm_exit(vdev);
399 return 0;
400 }
401
402 #ifdef CONFIG_PM
vfio_pci_core_runtime_suspend(struct device * dev)403 static int vfio_pci_core_runtime_suspend(struct device *dev)
404 {
405 struct vfio_pci_core_device *vdev = dev_get_drvdata(dev);
406
407 down_write(&vdev->memory_lock);
408 /*
409 * The user can move the device into D3hot state before invoking
410 * power management IOCTL. Move the device into D0 state here and then
411 * the pci-driver core runtime PM suspend function will move the device
412 * into the low power state. Also, for the devices which have
413 * NoSoftRst-, it will help in restoring the original state
414 * (saved locally in 'vdev->pm_save').
415 */
416 vfio_pci_set_power_state(vdev, PCI_D0);
417 up_write(&vdev->memory_lock);
418
419 /*
420 * If INTx is enabled, then mask INTx before going into the runtime
421 * suspended state and unmask the same in the runtime resume.
422 * If INTx has already been masked by the user, then
423 * vfio_pci_intx_mask() will return false and in that case, INTx
424 * should not be unmasked in the runtime resume.
425 */
426 vdev->pm_intx_masked = ((vdev->irq_type == VFIO_PCI_INTX_IRQ_INDEX) &&
427 vfio_pci_intx_mask(vdev));
428
429 return 0;
430 }
431
vfio_pci_core_runtime_resume(struct device * dev)432 static int vfio_pci_core_runtime_resume(struct device *dev)
433 {
434 struct vfio_pci_core_device *vdev = dev_get_drvdata(dev);
435
436 /*
437 * Resume with a pm_wake_eventfd_ctx signals the eventfd and exit
438 * low power mode.
439 */
440 down_write(&vdev->memory_lock);
441 if (vdev->pm_wake_eventfd_ctx) {
442 eventfd_signal(vdev->pm_wake_eventfd_ctx);
443 __vfio_pci_runtime_pm_exit(vdev);
444 }
445 up_write(&vdev->memory_lock);
446
447 if (vdev->pm_intx_masked)
448 vfio_pci_intx_unmask(vdev);
449
450 return 0;
451 }
452 #endif /* CONFIG_PM */
453
454 /*
455 * The pci-driver core runtime PM routines always save the device state
456 * before going into suspended state. If the device is going into low power
457 * state with only with runtime PM ops, then no explicit handling is needed
458 * for the devices which have NoSoftRst-.
459 */
460 static const struct dev_pm_ops vfio_pci_core_pm_ops = {
461 SET_RUNTIME_PM_OPS(vfio_pci_core_runtime_suspend,
462 vfio_pci_core_runtime_resume,
463 NULL)
464 };
465
vfio_pci_core_enable(struct vfio_pci_core_device * vdev)466 int vfio_pci_core_enable(struct vfio_pci_core_device *vdev)
467 {
468 struct pci_dev *pdev = vdev->pdev;
469 int ret;
470 u16 cmd;
471 u8 msix_pos;
472
473 if (!disable_idle_d3) {
474 ret = pm_runtime_resume_and_get(&pdev->dev);
475 if (ret < 0)
476 return ret;
477 }
478
479 /* Don't allow our initial saved state to include busmaster */
480 pci_clear_master(pdev);
481
482 ret = pci_enable_device(pdev);
483 if (ret)
484 goto out_power;
485
486 /* If reset fails because of the device lock, fail this path entirely */
487 ret = pci_try_reset_function(pdev);
488 if (ret == -EAGAIN)
489 goto out_disable_device;
490
491 vdev->reset_works = !ret;
492 pci_save_state(pdev);
493 vdev->pci_saved_state = pci_store_saved_state(pdev);
494 if (!vdev->pci_saved_state)
495 pci_dbg(pdev, "%s: Couldn't store saved state\n", __func__);
496
497 if (likely(!nointxmask)) {
498 if (vfio_pci_nointx(pdev)) {
499 pci_info(pdev, "Masking broken INTx support\n");
500 vdev->nointx = true;
501 pci_intx(pdev, 0);
502 } else
503 vdev->pci_2_3 = pci_intx_mask_supported(pdev);
504 }
505
506 pci_read_config_word(pdev, PCI_COMMAND, &cmd);
507 if (vdev->pci_2_3 && (cmd & PCI_COMMAND_INTX_DISABLE)) {
508 cmd &= ~PCI_COMMAND_INTX_DISABLE;
509 pci_write_config_word(pdev, PCI_COMMAND, cmd);
510 }
511
512 ret = vfio_pci_zdev_open_device(vdev);
513 if (ret)
514 goto out_free_state;
515
516 ret = vfio_config_init(vdev);
517 if (ret)
518 goto out_free_zdev;
519
520 msix_pos = pdev->msix_cap;
521 if (msix_pos) {
522 u16 flags;
523 u32 table;
524
525 pci_read_config_word(pdev, msix_pos + PCI_MSIX_FLAGS, &flags);
526 pci_read_config_dword(pdev, msix_pos + PCI_MSIX_TABLE, &table);
527
528 vdev->msix_bar = table & PCI_MSIX_TABLE_BIR;
529 vdev->msix_offset = table & PCI_MSIX_TABLE_OFFSET;
530 vdev->msix_size = ((flags & PCI_MSIX_FLAGS_QSIZE) + 1) * 16;
531 vdev->has_dyn_msix = pci_msix_can_alloc_dyn(pdev);
532 } else {
533 vdev->msix_bar = 0xFF;
534 vdev->has_dyn_msix = false;
535 }
536
537 if (!vfio_vga_disabled() && vfio_pci_is_vga(pdev))
538 vdev->has_vga = true;
539
540
541 return 0;
542
543 out_free_zdev:
544 vfio_pci_zdev_close_device(vdev);
545 out_free_state:
546 kfree(vdev->pci_saved_state);
547 vdev->pci_saved_state = NULL;
548 out_disable_device:
549 pci_disable_device(pdev);
550 out_power:
551 if (!disable_idle_d3)
552 pm_runtime_put(&pdev->dev);
553 return ret;
554 }
555 EXPORT_SYMBOL_GPL(vfio_pci_core_enable);
556
vfio_pci_core_disable(struct vfio_pci_core_device * vdev)557 void vfio_pci_core_disable(struct vfio_pci_core_device *vdev)
558 {
559 struct pci_dev *pdev = vdev->pdev;
560 struct vfio_pci_dummy_resource *dummy_res, *tmp;
561 struct vfio_pci_ioeventfd *ioeventfd, *ioeventfd_tmp;
562 int i, bar;
563
564 /* For needs_reset */
565 lockdep_assert_held(&vdev->vdev.dev_set->lock);
566
567 /*
568 * This function can be invoked while the power state is non-D0.
569 * This non-D0 power state can be with or without runtime PM.
570 * vfio_pci_runtime_pm_exit() will internally increment the usage
571 * count corresponding to pm_runtime_put() called during low power
572 * feature entry and then pm_runtime_resume() will wake up the device,
573 * if the device has already gone into the suspended state. Otherwise,
574 * the vfio_pci_set_power_state() will change the device power state
575 * to D0.
576 */
577 vfio_pci_runtime_pm_exit(vdev);
578 pm_runtime_resume(&pdev->dev);
579
580 /*
581 * This function calls __pci_reset_function_locked() which internally
582 * can use pci_pm_reset() for the function reset. pci_pm_reset() will
583 * fail if the power state is non-D0. Also, for the devices which
584 * have NoSoftRst-, the reset function can cause the PCI config space
585 * reset without restoring the original state (saved locally in
586 * 'vdev->pm_save').
587 */
588 vfio_pci_set_power_state(vdev, PCI_D0);
589
590 /* Stop the device from further DMA */
591 pci_clear_master(pdev);
592
593 vfio_pci_set_irqs_ioctl(vdev, VFIO_IRQ_SET_DATA_NONE |
594 VFIO_IRQ_SET_ACTION_TRIGGER,
595 vdev->irq_type, 0, 0, NULL);
596
597 /* Device closed, don't need mutex here */
598 list_for_each_entry_safe(ioeventfd, ioeventfd_tmp,
599 &vdev->ioeventfds_list, next) {
600 vfio_virqfd_disable(&ioeventfd->virqfd);
601 list_del(&ioeventfd->next);
602 kfree(ioeventfd);
603 }
604 vdev->ioeventfds_nr = 0;
605
606 vdev->virq_disabled = false;
607
608 for (i = 0; i < vdev->num_regions; i++)
609 vdev->region[i].ops->release(vdev, &vdev->region[i]);
610
611 vdev->num_regions = 0;
612 kfree(vdev->region);
613 vdev->region = NULL; /* don't krealloc a freed pointer */
614
615 vfio_config_free(vdev);
616
617 for (i = 0; i < PCI_STD_NUM_BARS; i++) {
618 bar = i + PCI_STD_RESOURCES;
619 if (!vdev->barmap[bar])
620 continue;
621 pci_iounmap(pdev, vdev->barmap[bar]);
622 pci_release_selected_regions(pdev, 1 << bar);
623 vdev->barmap[bar] = NULL;
624 }
625
626 list_for_each_entry_safe(dummy_res, tmp,
627 &vdev->dummy_resources_list, res_next) {
628 list_del(&dummy_res->res_next);
629 release_resource(&dummy_res->resource);
630 kfree(dummy_res);
631 }
632
633 vdev->needs_reset = true;
634
635 vfio_pci_zdev_close_device(vdev);
636
637 /*
638 * If we have saved state, restore it. If we can reset the device,
639 * even better. Resetting with current state seems better than
640 * nothing, but saving and restoring current state without reset
641 * is just busy work.
642 */
643 if (pci_load_and_free_saved_state(pdev, &vdev->pci_saved_state)) {
644 pci_info(pdev, "%s: Couldn't reload saved state\n", __func__);
645
646 if (!vdev->reset_works)
647 goto out;
648
649 pci_save_state(pdev);
650 }
651
652 /*
653 * Disable INTx and MSI, presumably to avoid spurious interrupts
654 * during reset. Stolen from pci_reset_function()
655 */
656 pci_write_config_word(pdev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE);
657
658 /*
659 * Try to get the locks ourselves to prevent a deadlock. The
660 * success of this is dependent on being able to lock the device,
661 * which is not always possible.
662 * We can not use the "try" reset interface here, which will
663 * overwrite the previously restored configuration information.
664 */
665 if (vdev->reset_works && pci_dev_trylock(pdev)) {
666 if (!__pci_reset_function_locked(pdev))
667 vdev->needs_reset = false;
668 pci_dev_unlock(pdev);
669 }
670
671 pci_restore_state(pdev);
672 out:
673 pci_disable_device(pdev);
674
675 vfio_pci_dev_set_try_reset(vdev->vdev.dev_set);
676
677 /* Put the pm-runtime usage counter acquired during enable */
678 if (!disable_idle_d3)
679 pm_runtime_put(&pdev->dev);
680 }
681 EXPORT_SYMBOL_GPL(vfio_pci_core_disable);
682
vfio_pci_core_close_device(struct vfio_device * core_vdev)683 void vfio_pci_core_close_device(struct vfio_device *core_vdev)
684 {
685 struct vfio_pci_core_device *vdev =
686 container_of(core_vdev, struct vfio_pci_core_device, vdev);
687
688 if (vdev->sriov_pf_core_dev) {
689 mutex_lock(&vdev->sriov_pf_core_dev->vf_token->lock);
690 WARN_ON(!vdev->sriov_pf_core_dev->vf_token->users);
691 vdev->sriov_pf_core_dev->vf_token->users--;
692 mutex_unlock(&vdev->sriov_pf_core_dev->vf_token->lock);
693 }
694 #if IS_ENABLED(CONFIG_EEH)
695 eeh_dev_release(vdev->pdev);
696 #endif
697 vfio_pci_core_disable(vdev);
698
699 mutex_lock(&vdev->igate);
700 if (vdev->err_trigger) {
701 eventfd_ctx_put(vdev->err_trigger);
702 vdev->err_trigger = NULL;
703 }
704 if (vdev->req_trigger) {
705 eventfd_ctx_put(vdev->req_trigger);
706 vdev->req_trigger = NULL;
707 }
708 mutex_unlock(&vdev->igate);
709 }
710 EXPORT_SYMBOL_GPL(vfio_pci_core_close_device);
711
vfio_pci_core_finish_enable(struct vfio_pci_core_device * vdev)712 void vfio_pci_core_finish_enable(struct vfio_pci_core_device *vdev)
713 {
714 vfio_pci_probe_mmaps(vdev);
715 #if IS_ENABLED(CONFIG_EEH)
716 eeh_dev_open(vdev->pdev);
717 #endif
718
719 if (vdev->sriov_pf_core_dev) {
720 mutex_lock(&vdev->sriov_pf_core_dev->vf_token->lock);
721 vdev->sriov_pf_core_dev->vf_token->users++;
722 mutex_unlock(&vdev->sriov_pf_core_dev->vf_token->lock);
723 }
724 }
725 EXPORT_SYMBOL_GPL(vfio_pci_core_finish_enable);
726
vfio_pci_get_irq_count(struct vfio_pci_core_device * vdev,int irq_type)727 static int vfio_pci_get_irq_count(struct vfio_pci_core_device *vdev, int irq_type)
728 {
729 if (irq_type == VFIO_PCI_INTX_IRQ_INDEX) {
730 u8 pin;
731
732 if (!IS_ENABLED(CONFIG_VFIO_PCI_INTX) ||
733 vdev->nointx || vdev->pdev->is_virtfn)
734 return 0;
735
736 pci_read_config_byte(vdev->pdev, PCI_INTERRUPT_PIN, &pin);
737
738 return pin ? 1 : 0;
739 } else if (irq_type == VFIO_PCI_MSI_IRQ_INDEX) {
740 u8 pos;
741 u16 flags;
742
743 pos = vdev->pdev->msi_cap;
744 if (pos) {
745 pci_read_config_word(vdev->pdev,
746 pos + PCI_MSI_FLAGS, &flags);
747 return 1 << ((flags & PCI_MSI_FLAGS_QMASK) >> 1);
748 }
749 } else if (irq_type == VFIO_PCI_MSIX_IRQ_INDEX) {
750 u8 pos;
751 u16 flags;
752
753 pos = vdev->pdev->msix_cap;
754 if (pos) {
755 pci_read_config_word(vdev->pdev,
756 pos + PCI_MSIX_FLAGS, &flags);
757
758 return (flags & PCI_MSIX_FLAGS_QSIZE) + 1;
759 }
760 } else if (irq_type == VFIO_PCI_ERR_IRQ_INDEX) {
761 if (pci_is_pcie(vdev->pdev))
762 return 1;
763 } else if (irq_type == VFIO_PCI_REQ_IRQ_INDEX) {
764 return 1;
765 }
766
767 return 0;
768 }
769
vfio_pci_count_devs(struct pci_dev * pdev,void * data)770 static int vfio_pci_count_devs(struct pci_dev *pdev, void *data)
771 {
772 (*(int *)data)++;
773 return 0;
774 }
775
776 struct vfio_pci_fill_info {
777 struct vfio_device *vdev;
778 struct vfio_pci_dependent_device *devices;
779 int nr_devices;
780 u32 count;
781 u32 flags;
782 };
783
vfio_pci_fill_devs(struct pci_dev * pdev,void * data)784 static int vfio_pci_fill_devs(struct pci_dev *pdev, void *data)
785 {
786 struct vfio_pci_dependent_device *info;
787 struct vfio_pci_fill_info *fill = data;
788
789 /* The topology changed since we counted devices */
790 if (fill->count >= fill->nr_devices)
791 return -EAGAIN;
792
793 info = &fill->devices[fill->count++];
794 info->segment = pci_domain_nr(pdev->bus);
795 info->bus = pdev->bus->number;
796 info->devfn = pdev->devfn;
797
798 if (fill->flags & VFIO_PCI_HOT_RESET_FLAG_DEV_ID) {
799 struct iommufd_ctx *iommufd = vfio_iommufd_device_ictx(fill->vdev);
800 struct vfio_device_set *dev_set = fill->vdev->dev_set;
801 struct vfio_device *vdev;
802
803 /*
804 * hot-reset requires all affected devices be represented in
805 * the dev_set.
806 */
807 vdev = vfio_find_device_in_devset(dev_set, &pdev->dev);
808 if (!vdev) {
809 info->devid = VFIO_PCI_DEVID_NOT_OWNED;
810 } else {
811 int id = vfio_iommufd_get_dev_id(vdev, iommufd);
812
813 if (id > 0)
814 info->devid = id;
815 else if (id == -ENOENT)
816 info->devid = VFIO_PCI_DEVID_OWNED;
817 else
818 info->devid = VFIO_PCI_DEVID_NOT_OWNED;
819 }
820 /* If devid is VFIO_PCI_DEVID_NOT_OWNED, clear owned flag. */
821 if (info->devid == VFIO_PCI_DEVID_NOT_OWNED)
822 fill->flags &= ~VFIO_PCI_HOT_RESET_FLAG_DEV_ID_OWNED;
823 } else {
824 struct iommu_group *iommu_group;
825
826 iommu_group = iommu_group_get(&pdev->dev);
827 if (!iommu_group)
828 return -EPERM; /* Cannot reset non-isolated devices */
829
830 info->group_id = iommu_group_id(iommu_group);
831 iommu_group_put(iommu_group);
832 }
833
834 return 0;
835 }
836
837 struct vfio_pci_group_info {
838 int count;
839 struct file **files;
840 };
841
vfio_pci_dev_below_slot(struct pci_dev * pdev,struct pci_slot * slot)842 static bool vfio_pci_dev_below_slot(struct pci_dev *pdev, struct pci_slot *slot)
843 {
844 for (; pdev; pdev = pdev->bus->self)
845 if (pdev->bus == slot->bus)
846 return (pdev->slot == slot);
847 return false;
848 }
849
850 struct vfio_pci_walk_info {
851 int (*fn)(struct pci_dev *pdev, void *data);
852 void *data;
853 struct pci_dev *pdev;
854 bool slot;
855 int ret;
856 };
857
vfio_pci_walk_wrapper(struct pci_dev * pdev,void * data)858 static int vfio_pci_walk_wrapper(struct pci_dev *pdev, void *data)
859 {
860 struct vfio_pci_walk_info *walk = data;
861
862 if (!walk->slot || vfio_pci_dev_below_slot(pdev, walk->pdev->slot))
863 walk->ret = walk->fn(pdev, walk->data);
864
865 return walk->ret;
866 }
867
vfio_pci_for_each_slot_or_bus(struct pci_dev * pdev,int (* fn)(struct pci_dev *,void * data),void * data,bool slot)868 static int vfio_pci_for_each_slot_or_bus(struct pci_dev *pdev,
869 int (*fn)(struct pci_dev *,
870 void *data), void *data,
871 bool slot)
872 {
873 struct vfio_pci_walk_info walk = {
874 .fn = fn, .data = data, .pdev = pdev, .slot = slot, .ret = 0,
875 };
876
877 pci_walk_bus(pdev->bus, vfio_pci_walk_wrapper, &walk);
878
879 return walk.ret;
880 }
881
msix_mmappable_cap(struct vfio_pci_core_device * vdev,struct vfio_info_cap * caps)882 static int msix_mmappable_cap(struct vfio_pci_core_device *vdev,
883 struct vfio_info_cap *caps)
884 {
885 struct vfio_info_cap_header header = {
886 .id = VFIO_REGION_INFO_CAP_MSIX_MAPPABLE,
887 .version = 1
888 };
889
890 return vfio_info_add_capability(caps, &header, sizeof(header));
891 }
892
vfio_pci_core_register_dev_region(struct vfio_pci_core_device * vdev,unsigned int type,unsigned int subtype,const struct vfio_pci_regops * ops,size_t size,u32 flags,void * data)893 int vfio_pci_core_register_dev_region(struct vfio_pci_core_device *vdev,
894 unsigned int type, unsigned int subtype,
895 const struct vfio_pci_regops *ops,
896 size_t size, u32 flags, void *data)
897 {
898 struct vfio_pci_region *region;
899
900 region = krealloc(vdev->region,
901 (vdev->num_regions + 1) * sizeof(*region),
902 GFP_KERNEL_ACCOUNT);
903 if (!region)
904 return -ENOMEM;
905
906 vdev->region = region;
907 vdev->region[vdev->num_regions].type = type;
908 vdev->region[vdev->num_regions].subtype = subtype;
909 vdev->region[vdev->num_regions].ops = ops;
910 vdev->region[vdev->num_regions].size = size;
911 vdev->region[vdev->num_regions].flags = flags;
912 vdev->region[vdev->num_regions].data = data;
913
914 vdev->num_regions++;
915
916 return 0;
917 }
918 EXPORT_SYMBOL_GPL(vfio_pci_core_register_dev_region);
919
vfio_pci_info_atomic_cap(struct vfio_pci_core_device * vdev,struct vfio_info_cap * caps)920 static int vfio_pci_info_atomic_cap(struct vfio_pci_core_device *vdev,
921 struct vfio_info_cap *caps)
922 {
923 struct vfio_device_info_cap_pci_atomic_comp cap = {
924 .header.id = VFIO_DEVICE_INFO_CAP_PCI_ATOMIC_COMP,
925 .header.version = 1
926 };
927 struct pci_dev *pdev = pci_physfn(vdev->pdev);
928 u32 devcap2;
929
930 pcie_capability_read_dword(pdev, PCI_EXP_DEVCAP2, &devcap2);
931
932 if ((devcap2 & PCI_EXP_DEVCAP2_ATOMIC_COMP32) &&
933 !pci_enable_atomic_ops_to_root(pdev, PCI_EXP_DEVCAP2_ATOMIC_COMP32))
934 cap.flags |= VFIO_PCI_ATOMIC_COMP32;
935
936 if ((devcap2 & PCI_EXP_DEVCAP2_ATOMIC_COMP64) &&
937 !pci_enable_atomic_ops_to_root(pdev, PCI_EXP_DEVCAP2_ATOMIC_COMP64))
938 cap.flags |= VFIO_PCI_ATOMIC_COMP64;
939
940 if ((devcap2 & PCI_EXP_DEVCAP2_ATOMIC_COMP128) &&
941 !pci_enable_atomic_ops_to_root(pdev,
942 PCI_EXP_DEVCAP2_ATOMIC_COMP128))
943 cap.flags |= VFIO_PCI_ATOMIC_COMP128;
944
945 if (!cap.flags)
946 return -ENODEV;
947
948 return vfio_info_add_capability(caps, &cap.header, sizeof(cap));
949 }
950
vfio_pci_ioctl_get_info(struct vfio_pci_core_device * vdev,struct vfio_device_info __user * arg)951 static int vfio_pci_ioctl_get_info(struct vfio_pci_core_device *vdev,
952 struct vfio_device_info __user *arg)
953 {
954 unsigned long minsz = offsetofend(struct vfio_device_info, num_irqs);
955 struct vfio_device_info info = {};
956 struct vfio_info_cap caps = { .buf = NULL, .size = 0 };
957 int ret;
958
959 if (copy_from_user(&info, arg, minsz))
960 return -EFAULT;
961
962 if (info.argsz < minsz)
963 return -EINVAL;
964
965 minsz = min_t(size_t, info.argsz, sizeof(info));
966
967 info.flags = VFIO_DEVICE_FLAGS_PCI;
968
969 if (vdev->reset_works)
970 info.flags |= VFIO_DEVICE_FLAGS_RESET;
971
972 info.num_regions = VFIO_PCI_NUM_REGIONS + vdev->num_regions;
973 info.num_irqs = VFIO_PCI_NUM_IRQS;
974
975 ret = vfio_pci_info_zdev_add_caps(vdev, &caps);
976 if (ret && ret != -ENODEV) {
977 pci_warn(vdev->pdev,
978 "Failed to setup zPCI info capabilities\n");
979 return ret;
980 }
981
982 ret = vfio_pci_info_atomic_cap(vdev, &caps);
983 if (ret && ret != -ENODEV) {
984 pci_warn(vdev->pdev,
985 "Failed to setup AtomicOps info capability\n");
986 return ret;
987 }
988
989 if (caps.size) {
990 info.flags |= VFIO_DEVICE_FLAGS_CAPS;
991 if (info.argsz < sizeof(info) + caps.size) {
992 info.argsz = sizeof(info) + caps.size;
993 } else {
994 vfio_info_cap_shift(&caps, sizeof(info));
995 if (copy_to_user(arg + 1, caps.buf, caps.size)) {
996 kfree(caps.buf);
997 return -EFAULT;
998 }
999 info.cap_offset = sizeof(*arg);
1000 }
1001
1002 kfree(caps.buf);
1003 }
1004
1005 return copy_to_user(arg, &info, minsz) ? -EFAULT : 0;
1006 }
1007
vfio_pci_ioctl_get_region_info(struct vfio_pci_core_device * vdev,struct vfio_region_info __user * arg)1008 static int vfio_pci_ioctl_get_region_info(struct vfio_pci_core_device *vdev,
1009 struct vfio_region_info __user *arg)
1010 {
1011 unsigned long minsz = offsetofend(struct vfio_region_info, offset);
1012 struct pci_dev *pdev = vdev->pdev;
1013 struct vfio_region_info info;
1014 struct vfio_info_cap caps = { .buf = NULL, .size = 0 };
1015 int i, ret;
1016
1017 if (copy_from_user(&info, arg, minsz))
1018 return -EFAULT;
1019
1020 if (info.argsz < minsz)
1021 return -EINVAL;
1022
1023 switch (info.index) {
1024 case VFIO_PCI_CONFIG_REGION_INDEX:
1025 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
1026 info.size = pdev->cfg_size;
1027 info.flags = VFIO_REGION_INFO_FLAG_READ |
1028 VFIO_REGION_INFO_FLAG_WRITE;
1029 break;
1030 case VFIO_PCI_BAR0_REGION_INDEX ... VFIO_PCI_BAR5_REGION_INDEX:
1031 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
1032 info.size = pci_resource_len(pdev, info.index);
1033 if (!info.size) {
1034 info.flags = 0;
1035 break;
1036 }
1037
1038 info.flags = VFIO_REGION_INFO_FLAG_READ |
1039 VFIO_REGION_INFO_FLAG_WRITE;
1040 if (vdev->bar_mmap_supported[info.index]) {
1041 info.flags |= VFIO_REGION_INFO_FLAG_MMAP;
1042 if (info.index == vdev->msix_bar) {
1043 ret = msix_mmappable_cap(vdev, &caps);
1044 if (ret)
1045 return ret;
1046 }
1047 }
1048
1049 break;
1050 case VFIO_PCI_ROM_REGION_INDEX: {
1051 void __iomem *io;
1052 size_t size;
1053 u16 cmd;
1054
1055 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
1056 info.flags = 0;
1057
1058 /* Report the BAR size, not the ROM size */
1059 info.size = pci_resource_len(pdev, info.index);
1060 if (!info.size) {
1061 /* Shadow ROMs appear as PCI option ROMs */
1062 if (pdev->resource[PCI_ROM_RESOURCE].flags &
1063 IORESOURCE_ROM_SHADOW)
1064 info.size = 0x20000;
1065 else
1066 break;
1067 }
1068
1069 /*
1070 * Is it really there? Enable memory decode for implicit access
1071 * in pci_map_rom().
1072 */
1073 cmd = vfio_pci_memory_lock_and_enable(vdev);
1074 io = pci_map_rom(pdev, &size);
1075 if (io) {
1076 info.flags = VFIO_REGION_INFO_FLAG_READ;
1077 pci_unmap_rom(pdev, io);
1078 } else {
1079 info.size = 0;
1080 }
1081 vfio_pci_memory_unlock_and_restore(vdev, cmd);
1082
1083 break;
1084 }
1085 case VFIO_PCI_VGA_REGION_INDEX:
1086 if (!vdev->has_vga)
1087 return -EINVAL;
1088
1089 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
1090 info.size = 0xc0000;
1091 info.flags = VFIO_REGION_INFO_FLAG_READ |
1092 VFIO_REGION_INFO_FLAG_WRITE;
1093
1094 break;
1095 default: {
1096 struct vfio_region_info_cap_type cap_type = {
1097 .header.id = VFIO_REGION_INFO_CAP_TYPE,
1098 .header.version = 1
1099 };
1100
1101 if (info.index >= VFIO_PCI_NUM_REGIONS + vdev->num_regions)
1102 return -EINVAL;
1103 info.index = array_index_nospec(
1104 info.index, VFIO_PCI_NUM_REGIONS + vdev->num_regions);
1105
1106 i = info.index - VFIO_PCI_NUM_REGIONS;
1107
1108 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
1109 info.size = vdev->region[i].size;
1110 info.flags = vdev->region[i].flags;
1111
1112 cap_type.type = vdev->region[i].type;
1113 cap_type.subtype = vdev->region[i].subtype;
1114
1115 ret = vfio_info_add_capability(&caps, &cap_type.header,
1116 sizeof(cap_type));
1117 if (ret)
1118 return ret;
1119
1120 if (vdev->region[i].ops->add_capability) {
1121 ret = vdev->region[i].ops->add_capability(
1122 vdev, &vdev->region[i], &caps);
1123 if (ret)
1124 return ret;
1125 }
1126 }
1127 }
1128
1129 if (caps.size) {
1130 info.flags |= VFIO_REGION_INFO_FLAG_CAPS;
1131 if (info.argsz < sizeof(info) + caps.size) {
1132 info.argsz = sizeof(info) + caps.size;
1133 info.cap_offset = 0;
1134 } else {
1135 vfio_info_cap_shift(&caps, sizeof(info));
1136 if (copy_to_user(arg + 1, caps.buf, caps.size)) {
1137 kfree(caps.buf);
1138 return -EFAULT;
1139 }
1140 info.cap_offset = sizeof(*arg);
1141 }
1142
1143 kfree(caps.buf);
1144 }
1145
1146 return copy_to_user(arg, &info, minsz) ? -EFAULT : 0;
1147 }
1148
vfio_pci_ioctl_get_irq_info(struct vfio_pci_core_device * vdev,struct vfio_irq_info __user * arg)1149 static int vfio_pci_ioctl_get_irq_info(struct vfio_pci_core_device *vdev,
1150 struct vfio_irq_info __user *arg)
1151 {
1152 unsigned long minsz = offsetofend(struct vfio_irq_info, count);
1153 struct vfio_irq_info info;
1154
1155 if (copy_from_user(&info, arg, minsz))
1156 return -EFAULT;
1157
1158 if (info.argsz < minsz || info.index >= VFIO_PCI_NUM_IRQS)
1159 return -EINVAL;
1160
1161 switch (info.index) {
1162 case VFIO_PCI_INTX_IRQ_INDEX ... VFIO_PCI_MSIX_IRQ_INDEX:
1163 case VFIO_PCI_REQ_IRQ_INDEX:
1164 break;
1165 case VFIO_PCI_ERR_IRQ_INDEX:
1166 if (pci_is_pcie(vdev->pdev))
1167 break;
1168 fallthrough;
1169 default:
1170 return -EINVAL;
1171 }
1172
1173 info.flags = VFIO_IRQ_INFO_EVENTFD;
1174
1175 info.count = vfio_pci_get_irq_count(vdev, info.index);
1176
1177 if (info.index == VFIO_PCI_INTX_IRQ_INDEX)
1178 info.flags |=
1179 (VFIO_IRQ_INFO_MASKABLE | VFIO_IRQ_INFO_AUTOMASKED);
1180 else if (info.index != VFIO_PCI_MSIX_IRQ_INDEX || !vdev->has_dyn_msix)
1181 info.flags |= VFIO_IRQ_INFO_NORESIZE;
1182
1183 return copy_to_user(arg, &info, minsz) ? -EFAULT : 0;
1184 }
1185
vfio_pci_ioctl_set_irqs(struct vfio_pci_core_device * vdev,struct vfio_irq_set __user * arg)1186 static int vfio_pci_ioctl_set_irqs(struct vfio_pci_core_device *vdev,
1187 struct vfio_irq_set __user *arg)
1188 {
1189 unsigned long minsz = offsetofend(struct vfio_irq_set, count);
1190 struct vfio_irq_set hdr;
1191 u8 *data = NULL;
1192 int max, ret = 0;
1193 size_t data_size = 0;
1194
1195 if (copy_from_user(&hdr, arg, minsz))
1196 return -EFAULT;
1197
1198 max = vfio_pci_get_irq_count(vdev, hdr.index);
1199
1200 ret = vfio_set_irqs_validate_and_prepare(&hdr, max, VFIO_PCI_NUM_IRQS,
1201 &data_size);
1202 if (ret)
1203 return ret;
1204
1205 if (data_size) {
1206 data = memdup_user(&arg->data, data_size);
1207 if (IS_ERR(data))
1208 return PTR_ERR(data);
1209 }
1210
1211 mutex_lock(&vdev->igate);
1212
1213 ret = vfio_pci_set_irqs_ioctl(vdev, hdr.flags, hdr.index, hdr.start,
1214 hdr.count, data);
1215
1216 mutex_unlock(&vdev->igate);
1217 kfree(data);
1218
1219 return ret;
1220 }
1221
vfio_pci_ioctl_reset(struct vfio_pci_core_device * vdev,void __user * arg)1222 static int vfio_pci_ioctl_reset(struct vfio_pci_core_device *vdev,
1223 void __user *arg)
1224 {
1225 int ret;
1226
1227 if (!vdev->reset_works)
1228 return -EINVAL;
1229
1230 vfio_pci_zap_and_down_write_memory_lock(vdev);
1231
1232 /*
1233 * This function can be invoked while the power state is non-D0. If
1234 * pci_try_reset_function() has been called while the power state is
1235 * non-D0, then pci_try_reset_function() will internally set the power
1236 * state to D0 without vfio driver involvement. For the devices which
1237 * have NoSoftRst-, the reset function can cause the PCI config space
1238 * reset without restoring the original state (saved locally in
1239 * 'vdev->pm_save').
1240 */
1241 vfio_pci_set_power_state(vdev, PCI_D0);
1242
1243 ret = pci_try_reset_function(vdev->pdev);
1244 up_write(&vdev->memory_lock);
1245
1246 return ret;
1247 }
1248
vfio_pci_ioctl_get_pci_hot_reset_info(struct vfio_pci_core_device * vdev,struct vfio_pci_hot_reset_info __user * arg)1249 static int vfio_pci_ioctl_get_pci_hot_reset_info(
1250 struct vfio_pci_core_device *vdev,
1251 struct vfio_pci_hot_reset_info __user *arg)
1252 {
1253 unsigned long minsz =
1254 offsetofend(struct vfio_pci_hot_reset_info, count);
1255 struct vfio_pci_dependent_device *devices = NULL;
1256 struct vfio_pci_hot_reset_info hdr;
1257 struct vfio_pci_fill_info fill = {};
1258 bool slot = false;
1259 int ret, count = 0;
1260
1261 if (copy_from_user(&hdr, arg, minsz))
1262 return -EFAULT;
1263
1264 if (hdr.argsz < minsz)
1265 return -EINVAL;
1266
1267 hdr.flags = 0;
1268
1269 /* Can we do a slot or bus reset or neither? */
1270 if (!pci_probe_reset_slot(vdev->pdev->slot))
1271 slot = true;
1272 else if (pci_probe_reset_bus(vdev->pdev->bus))
1273 return -ENODEV;
1274
1275 ret = vfio_pci_for_each_slot_or_bus(vdev->pdev, vfio_pci_count_devs,
1276 &count, slot);
1277 if (ret)
1278 return ret;
1279
1280 if (WARN_ON(!count)) /* Should always be at least one */
1281 return -ERANGE;
1282
1283 if (count > (hdr.argsz - sizeof(hdr)) / sizeof(*devices)) {
1284 hdr.count = count;
1285 ret = -ENOSPC;
1286 goto header;
1287 }
1288
1289 devices = kcalloc(count, sizeof(*devices), GFP_KERNEL);
1290 if (!devices)
1291 return -ENOMEM;
1292
1293 fill.devices = devices;
1294 fill.nr_devices = count;
1295 fill.vdev = &vdev->vdev;
1296
1297 if (vfio_device_cdev_opened(&vdev->vdev))
1298 fill.flags |= VFIO_PCI_HOT_RESET_FLAG_DEV_ID |
1299 VFIO_PCI_HOT_RESET_FLAG_DEV_ID_OWNED;
1300
1301 mutex_lock(&vdev->vdev.dev_set->lock);
1302 ret = vfio_pci_for_each_slot_or_bus(vdev->pdev, vfio_pci_fill_devs,
1303 &fill, slot);
1304 mutex_unlock(&vdev->vdev.dev_set->lock);
1305 if (ret)
1306 goto out;
1307
1308 if (copy_to_user(arg->devices, devices,
1309 sizeof(*devices) * fill.count)) {
1310 ret = -EFAULT;
1311 goto out;
1312 }
1313
1314 hdr.count = fill.count;
1315 hdr.flags = fill.flags;
1316
1317 header:
1318 if (copy_to_user(arg, &hdr, minsz))
1319 ret = -EFAULT;
1320 out:
1321 kfree(devices);
1322 return ret;
1323 }
1324
1325 static int
vfio_pci_ioctl_pci_hot_reset_groups(struct vfio_pci_core_device * vdev,u32 array_count,bool slot,struct vfio_pci_hot_reset __user * arg)1326 vfio_pci_ioctl_pci_hot_reset_groups(struct vfio_pci_core_device *vdev,
1327 u32 array_count, bool slot,
1328 struct vfio_pci_hot_reset __user *arg)
1329 {
1330 int32_t *group_fds;
1331 struct file **files;
1332 struct vfio_pci_group_info info;
1333 int file_idx, count = 0, ret = 0;
1334
1335 /*
1336 * We can't let userspace give us an arbitrarily large buffer to copy,
1337 * so verify how many we think there could be. Note groups can have
1338 * multiple devices so one group per device is the max.
1339 */
1340 ret = vfio_pci_for_each_slot_or_bus(vdev->pdev, vfio_pci_count_devs,
1341 &count, slot);
1342 if (ret)
1343 return ret;
1344
1345 if (array_count > count)
1346 return -EINVAL;
1347
1348 group_fds = kcalloc(array_count, sizeof(*group_fds), GFP_KERNEL);
1349 files = kcalloc(array_count, sizeof(*files), GFP_KERNEL);
1350 if (!group_fds || !files) {
1351 kfree(group_fds);
1352 kfree(files);
1353 return -ENOMEM;
1354 }
1355
1356 if (copy_from_user(group_fds, arg->group_fds,
1357 array_count * sizeof(*group_fds))) {
1358 kfree(group_fds);
1359 kfree(files);
1360 return -EFAULT;
1361 }
1362
1363 /*
1364 * Get the group file for each fd to ensure the group is held across
1365 * the reset
1366 */
1367 for (file_idx = 0; file_idx < array_count; file_idx++) {
1368 struct file *file = fget(group_fds[file_idx]);
1369
1370 if (!file) {
1371 ret = -EBADF;
1372 break;
1373 }
1374
1375 /* Ensure the FD is a vfio group FD.*/
1376 if (!vfio_file_is_group(file)) {
1377 fput(file);
1378 ret = -EINVAL;
1379 break;
1380 }
1381
1382 files[file_idx] = file;
1383 }
1384
1385 kfree(group_fds);
1386
1387 /* release reference to groups on error */
1388 if (ret)
1389 goto hot_reset_release;
1390
1391 info.count = array_count;
1392 info.files = files;
1393
1394 ret = vfio_pci_dev_set_hot_reset(vdev->vdev.dev_set, &info, NULL);
1395
1396 hot_reset_release:
1397 for (file_idx--; file_idx >= 0; file_idx--)
1398 fput(files[file_idx]);
1399
1400 kfree(files);
1401 return ret;
1402 }
1403
vfio_pci_ioctl_pci_hot_reset(struct vfio_pci_core_device * vdev,struct vfio_pci_hot_reset __user * arg)1404 static int vfio_pci_ioctl_pci_hot_reset(struct vfio_pci_core_device *vdev,
1405 struct vfio_pci_hot_reset __user *arg)
1406 {
1407 unsigned long minsz = offsetofend(struct vfio_pci_hot_reset, count);
1408 struct vfio_pci_hot_reset hdr;
1409 bool slot = false;
1410
1411 if (copy_from_user(&hdr, arg, minsz))
1412 return -EFAULT;
1413
1414 if (hdr.argsz < minsz || hdr.flags)
1415 return -EINVAL;
1416
1417 /* zero-length array is only for cdev opened devices */
1418 if (!!hdr.count == vfio_device_cdev_opened(&vdev->vdev))
1419 return -EINVAL;
1420
1421 /* Can we do a slot or bus reset or neither? */
1422 if (!pci_probe_reset_slot(vdev->pdev->slot))
1423 slot = true;
1424 else if (pci_probe_reset_bus(vdev->pdev->bus))
1425 return -ENODEV;
1426
1427 if (hdr.count)
1428 return vfio_pci_ioctl_pci_hot_reset_groups(vdev, hdr.count, slot, arg);
1429
1430 return vfio_pci_dev_set_hot_reset(vdev->vdev.dev_set, NULL,
1431 vfio_iommufd_device_ictx(&vdev->vdev));
1432 }
1433
vfio_pci_ioctl_ioeventfd(struct vfio_pci_core_device * vdev,struct vfio_device_ioeventfd __user * arg)1434 static int vfio_pci_ioctl_ioeventfd(struct vfio_pci_core_device *vdev,
1435 struct vfio_device_ioeventfd __user *arg)
1436 {
1437 unsigned long minsz = offsetofend(struct vfio_device_ioeventfd, fd);
1438 struct vfio_device_ioeventfd ioeventfd;
1439 int count;
1440
1441 if (copy_from_user(&ioeventfd, arg, minsz))
1442 return -EFAULT;
1443
1444 if (ioeventfd.argsz < minsz)
1445 return -EINVAL;
1446
1447 if (ioeventfd.flags & ~VFIO_DEVICE_IOEVENTFD_SIZE_MASK)
1448 return -EINVAL;
1449
1450 count = ioeventfd.flags & VFIO_DEVICE_IOEVENTFD_SIZE_MASK;
1451
1452 if (hweight8(count) != 1 || ioeventfd.fd < -1)
1453 return -EINVAL;
1454
1455 return vfio_pci_ioeventfd(vdev, ioeventfd.offset, ioeventfd.data, count,
1456 ioeventfd.fd);
1457 }
1458
vfio_pci_core_ioctl(struct vfio_device * core_vdev,unsigned int cmd,unsigned long arg)1459 long vfio_pci_core_ioctl(struct vfio_device *core_vdev, unsigned int cmd,
1460 unsigned long arg)
1461 {
1462 struct vfio_pci_core_device *vdev =
1463 container_of(core_vdev, struct vfio_pci_core_device, vdev);
1464 void __user *uarg = (void __user *)arg;
1465
1466 switch (cmd) {
1467 case VFIO_DEVICE_GET_INFO:
1468 return vfio_pci_ioctl_get_info(vdev, uarg);
1469 case VFIO_DEVICE_GET_IRQ_INFO:
1470 return vfio_pci_ioctl_get_irq_info(vdev, uarg);
1471 case VFIO_DEVICE_GET_PCI_HOT_RESET_INFO:
1472 return vfio_pci_ioctl_get_pci_hot_reset_info(vdev, uarg);
1473 case VFIO_DEVICE_GET_REGION_INFO:
1474 return vfio_pci_ioctl_get_region_info(vdev, uarg);
1475 case VFIO_DEVICE_IOEVENTFD:
1476 return vfio_pci_ioctl_ioeventfd(vdev, uarg);
1477 case VFIO_DEVICE_PCI_HOT_RESET:
1478 return vfio_pci_ioctl_pci_hot_reset(vdev, uarg);
1479 case VFIO_DEVICE_RESET:
1480 return vfio_pci_ioctl_reset(vdev, uarg);
1481 case VFIO_DEVICE_SET_IRQS:
1482 return vfio_pci_ioctl_set_irqs(vdev, uarg);
1483 default:
1484 return -ENOTTY;
1485 }
1486 }
1487 EXPORT_SYMBOL_GPL(vfio_pci_core_ioctl);
1488
vfio_pci_core_feature_token(struct vfio_device * device,u32 flags,uuid_t __user * arg,size_t argsz)1489 static int vfio_pci_core_feature_token(struct vfio_device *device, u32 flags,
1490 uuid_t __user *arg, size_t argsz)
1491 {
1492 struct vfio_pci_core_device *vdev =
1493 container_of(device, struct vfio_pci_core_device, vdev);
1494 uuid_t uuid;
1495 int ret;
1496
1497 if (!vdev->vf_token)
1498 return -ENOTTY;
1499 /*
1500 * We do not support GET of the VF Token UUID as this could
1501 * expose the token of the previous device user.
1502 */
1503 ret = vfio_check_feature(flags, argsz, VFIO_DEVICE_FEATURE_SET,
1504 sizeof(uuid));
1505 if (ret != 1)
1506 return ret;
1507
1508 if (copy_from_user(&uuid, arg, sizeof(uuid)))
1509 return -EFAULT;
1510
1511 mutex_lock(&vdev->vf_token->lock);
1512 uuid_copy(&vdev->vf_token->uuid, &uuid);
1513 mutex_unlock(&vdev->vf_token->lock);
1514 return 0;
1515 }
1516
vfio_pci_core_ioctl_feature(struct vfio_device * device,u32 flags,void __user * arg,size_t argsz)1517 int vfio_pci_core_ioctl_feature(struct vfio_device *device, u32 flags,
1518 void __user *arg, size_t argsz)
1519 {
1520 switch (flags & VFIO_DEVICE_FEATURE_MASK) {
1521 case VFIO_DEVICE_FEATURE_LOW_POWER_ENTRY:
1522 return vfio_pci_core_pm_entry(device, flags, arg, argsz);
1523 case VFIO_DEVICE_FEATURE_LOW_POWER_ENTRY_WITH_WAKEUP:
1524 return vfio_pci_core_pm_entry_with_wakeup(device, flags,
1525 arg, argsz);
1526 case VFIO_DEVICE_FEATURE_LOW_POWER_EXIT:
1527 return vfio_pci_core_pm_exit(device, flags, arg, argsz);
1528 case VFIO_DEVICE_FEATURE_PCI_VF_TOKEN:
1529 return vfio_pci_core_feature_token(device, flags, arg, argsz);
1530 default:
1531 return -ENOTTY;
1532 }
1533 }
1534 EXPORT_SYMBOL_GPL(vfio_pci_core_ioctl_feature);
1535
vfio_pci_rw(struct vfio_pci_core_device * vdev,char __user * buf,size_t count,loff_t * ppos,bool iswrite)1536 static ssize_t vfio_pci_rw(struct vfio_pci_core_device *vdev, char __user *buf,
1537 size_t count, loff_t *ppos, bool iswrite)
1538 {
1539 unsigned int index = VFIO_PCI_OFFSET_TO_INDEX(*ppos);
1540 int ret;
1541
1542 if (index >= VFIO_PCI_NUM_REGIONS + vdev->num_regions)
1543 return -EINVAL;
1544
1545 ret = pm_runtime_resume_and_get(&vdev->pdev->dev);
1546 if (ret) {
1547 pci_info_ratelimited(vdev->pdev, "runtime resume failed %d\n",
1548 ret);
1549 return -EIO;
1550 }
1551
1552 switch (index) {
1553 case VFIO_PCI_CONFIG_REGION_INDEX:
1554 ret = vfio_pci_config_rw(vdev, buf, count, ppos, iswrite);
1555 break;
1556
1557 case VFIO_PCI_ROM_REGION_INDEX:
1558 if (iswrite)
1559 ret = -EINVAL;
1560 else
1561 ret = vfio_pci_bar_rw(vdev, buf, count, ppos, false);
1562 break;
1563
1564 case VFIO_PCI_BAR0_REGION_INDEX ... VFIO_PCI_BAR5_REGION_INDEX:
1565 ret = vfio_pci_bar_rw(vdev, buf, count, ppos, iswrite);
1566 break;
1567
1568 case VFIO_PCI_VGA_REGION_INDEX:
1569 ret = vfio_pci_vga_rw(vdev, buf, count, ppos, iswrite);
1570 break;
1571
1572 default:
1573 index -= VFIO_PCI_NUM_REGIONS;
1574 ret = vdev->region[index].ops->rw(vdev, buf,
1575 count, ppos, iswrite);
1576 break;
1577 }
1578
1579 pm_runtime_put(&vdev->pdev->dev);
1580 return ret;
1581 }
1582
vfio_pci_core_read(struct vfio_device * core_vdev,char __user * buf,size_t count,loff_t * ppos)1583 ssize_t vfio_pci_core_read(struct vfio_device *core_vdev, char __user *buf,
1584 size_t count, loff_t *ppos)
1585 {
1586 struct vfio_pci_core_device *vdev =
1587 container_of(core_vdev, struct vfio_pci_core_device, vdev);
1588
1589 if (!count)
1590 return 0;
1591
1592 return vfio_pci_rw(vdev, buf, count, ppos, false);
1593 }
1594 EXPORT_SYMBOL_GPL(vfio_pci_core_read);
1595
vfio_pci_core_write(struct vfio_device * core_vdev,const char __user * buf,size_t count,loff_t * ppos)1596 ssize_t vfio_pci_core_write(struct vfio_device *core_vdev, const char __user *buf,
1597 size_t count, loff_t *ppos)
1598 {
1599 struct vfio_pci_core_device *vdev =
1600 container_of(core_vdev, struct vfio_pci_core_device, vdev);
1601
1602 if (!count)
1603 return 0;
1604
1605 return vfio_pci_rw(vdev, (char __user *)buf, count, ppos, true);
1606 }
1607 EXPORT_SYMBOL_GPL(vfio_pci_core_write);
1608
vfio_pci_zap_bars(struct vfio_pci_core_device * vdev)1609 static void vfio_pci_zap_bars(struct vfio_pci_core_device *vdev)
1610 {
1611 struct vfio_device *core_vdev = &vdev->vdev;
1612 loff_t start = VFIO_PCI_INDEX_TO_OFFSET(VFIO_PCI_BAR0_REGION_INDEX);
1613 loff_t end = VFIO_PCI_INDEX_TO_OFFSET(VFIO_PCI_ROM_REGION_INDEX);
1614 loff_t len = end - start;
1615
1616 unmap_mapping_range(core_vdev->inode->i_mapping, start, len, true);
1617 }
1618
vfio_pci_zap_and_down_write_memory_lock(struct vfio_pci_core_device * vdev)1619 void vfio_pci_zap_and_down_write_memory_lock(struct vfio_pci_core_device *vdev)
1620 {
1621 down_write(&vdev->memory_lock);
1622 vfio_pci_zap_bars(vdev);
1623 }
1624
vfio_pci_memory_lock_and_enable(struct vfio_pci_core_device * vdev)1625 u16 vfio_pci_memory_lock_and_enable(struct vfio_pci_core_device *vdev)
1626 {
1627 u16 cmd;
1628
1629 down_write(&vdev->memory_lock);
1630 pci_read_config_word(vdev->pdev, PCI_COMMAND, &cmd);
1631 if (!(cmd & PCI_COMMAND_MEMORY))
1632 pci_write_config_word(vdev->pdev, PCI_COMMAND,
1633 cmd | PCI_COMMAND_MEMORY);
1634
1635 return cmd;
1636 }
1637
vfio_pci_memory_unlock_and_restore(struct vfio_pci_core_device * vdev,u16 cmd)1638 void vfio_pci_memory_unlock_and_restore(struct vfio_pci_core_device *vdev, u16 cmd)
1639 {
1640 pci_write_config_word(vdev->pdev, PCI_COMMAND, cmd);
1641 up_write(&vdev->memory_lock);
1642 }
1643
vma_to_pfn(struct vm_area_struct * vma)1644 static unsigned long vma_to_pfn(struct vm_area_struct *vma)
1645 {
1646 struct vfio_pci_core_device *vdev = vma->vm_private_data;
1647 int index = vma->vm_pgoff >> (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT);
1648 u64 pgoff;
1649
1650 pgoff = vma->vm_pgoff &
1651 ((1U << (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
1652
1653 return (pci_resource_start(vdev->pdev, index) >> PAGE_SHIFT) + pgoff;
1654 }
1655
vfio_pci_mmap_huge_fault(struct vm_fault * vmf,unsigned int order)1656 static vm_fault_t vfio_pci_mmap_huge_fault(struct vm_fault *vmf,
1657 unsigned int order)
1658 {
1659 struct vm_area_struct *vma = vmf->vma;
1660 struct vfio_pci_core_device *vdev = vma->vm_private_data;
1661 unsigned long pfn, pgoff = vmf->pgoff - vma->vm_pgoff;
1662 vm_fault_t ret = VM_FAULT_SIGBUS;
1663
1664 pfn = vma_to_pfn(vma) + pgoff;
1665
1666 if (order && (pfn & ((1 << order) - 1) ||
1667 vmf->address & ((PAGE_SIZE << order) - 1) ||
1668 vmf->address + (PAGE_SIZE << order) > vma->vm_end)) {
1669 ret = VM_FAULT_FALLBACK;
1670 goto out;
1671 }
1672
1673 down_read(&vdev->memory_lock);
1674
1675 if (vdev->pm_runtime_engaged || !__vfio_pci_memory_enabled(vdev))
1676 goto out_unlock;
1677
1678 switch (order) {
1679 case 0:
1680 ret = vmf_insert_pfn(vma, vmf->address, pfn);
1681 break;
1682 #ifdef CONFIG_ARCH_SUPPORTS_PMD_PFNMAP
1683 case PMD_ORDER:
1684 ret = vmf_insert_pfn_pmd(vmf,
1685 __pfn_to_pfn_t(pfn, PFN_DEV), false);
1686 break;
1687 #endif
1688 #ifdef CONFIG_ARCH_SUPPORTS_PUD_PFNMAP
1689 case PUD_ORDER:
1690 ret = vmf_insert_pfn_pud(vmf,
1691 __pfn_to_pfn_t(pfn, PFN_DEV), false);
1692 break;
1693 #endif
1694 default:
1695 ret = VM_FAULT_FALLBACK;
1696 }
1697
1698 out_unlock:
1699 up_read(&vdev->memory_lock);
1700 out:
1701 dev_dbg_ratelimited(&vdev->pdev->dev,
1702 "%s(,order = %d) BAR %ld page offset 0x%lx: 0x%x\n",
1703 __func__, order,
1704 vma->vm_pgoff >>
1705 (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT),
1706 pgoff, (unsigned int)ret);
1707
1708 return ret;
1709 }
1710
vfio_pci_mmap_page_fault(struct vm_fault * vmf)1711 static vm_fault_t vfio_pci_mmap_page_fault(struct vm_fault *vmf)
1712 {
1713 return vfio_pci_mmap_huge_fault(vmf, 0);
1714 }
1715
1716 static const struct vm_operations_struct vfio_pci_mmap_ops = {
1717 .fault = vfio_pci_mmap_page_fault,
1718 #ifdef CONFIG_ARCH_SUPPORTS_HUGE_PFNMAP
1719 .huge_fault = vfio_pci_mmap_huge_fault,
1720 #endif
1721 };
1722
vfio_pci_core_mmap(struct vfio_device * core_vdev,struct vm_area_struct * vma)1723 int vfio_pci_core_mmap(struct vfio_device *core_vdev, struct vm_area_struct *vma)
1724 {
1725 struct vfio_pci_core_device *vdev =
1726 container_of(core_vdev, struct vfio_pci_core_device, vdev);
1727 struct pci_dev *pdev = vdev->pdev;
1728 unsigned int index;
1729 u64 phys_len, req_len, pgoff, req_start;
1730 int ret;
1731
1732 index = vma->vm_pgoff >> (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT);
1733
1734 if (index >= VFIO_PCI_NUM_REGIONS + vdev->num_regions)
1735 return -EINVAL;
1736 if (vma->vm_end < vma->vm_start)
1737 return -EINVAL;
1738 if ((vma->vm_flags & VM_SHARED) == 0)
1739 return -EINVAL;
1740 if (index >= VFIO_PCI_NUM_REGIONS) {
1741 int regnum = index - VFIO_PCI_NUM_REGIONS;
1742 struct vfio_pci_region *region = vdev->region + regnum;
1743
1744 if (region->ops && region->ops->mmap &&
1745 (region->flags & VFIO_REGION_INFO_FLAG_MMAP))
1746 return region->ops->mmap(vdev, region, vma);
1747 return -EINVAL;
1748 }
1749 if (index >= VFIO_PCI_ROM_REGION_INDEX)
1750 return -EINVAL;
1751 if (!vdev->bar_mmap_supported[index])
1752 return -EINVAL;
1753
1754 phys_len = PAGE_ALIGN(pci_resource_len(pdev, index));
1755 req_len = vma->vm_end - vma->vm_start;
1756 pgoff = vma->vm_pgoff &
1757 ((1U << (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
1758 req_start = pgoff << PAGE_SHIFT;
1759
1760 if (req_start + req_len > phys_len)
1761 return -EINVAL;
1762
1763 /*
1764 * Even though we don't make use of the barmap for the mmap,
1765 * we need to request the region and the barmap tracks that.
1766 */
1767 if (!vdev->barmap[index]) {
1768 ret = pci_request_selected_regions(pdev,
1769 1 << index, "vfio-pci");
1770 if (ret)
1771 return ret;
1772
1773 vdev->barmap[index] = pci_iomap(pdev, index, 0);
1774 if (!vdev->barmap[index]) {
1775 pci_release_selected_regions(pdev, 1 << index);
1776 return -ENOMEM;
1777 }
1778 }
1779
1780 vma->vm_private_data = vdev;
1781 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
1782 vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
1783
1784 /*
1785 * Set vm_flags now, they should not be changed in the fault handler.
1786 * We want the same flags and page protection (decrypted above) as
1787 * io_remap_pfn_range() would set.
1788 *
1789 * VM_ALLOW_ANY_UNCACHED: The VMA flag is implemented for ARM64,
1790 * allowing KVM stage 2 device mapping attributes to use Normal-NC
1791 * rather than DEVICE_nGnRE, which allows guest mappings
1792 * supporting write-combining attributes (WC). ARM does not
1793 * architecturally guarantee this is safe, and indeed some MMIO
1794 * regions like the GICv2 VCPU interface can trigger uncontained
1795 * faults if Normal-NC is used.
1796 *
1797 * To safely use VFIO in KVM the platform must guarantee full
1798 * safety in the guest where no action taken against a MMIO
1799 * mapping can trigger an uncontained failure. The assumption is
1800 * that most VFIO PCI platforms support this for both mapping types,
1801 * at least in common flows, based on some expectations of how
1802 * PCI IP is integrated. Hence VM_ALLOW_ANY_UNCACHED is set in
1803 * the VMA flags.
1804 */
1805 vm_flags_set(vma, VM_ALLOW_ANY_UNCACHED | VM_IO | VM_PFNMAP |
1806 VM_DONTEXPAND | VM_DONTDUMP);
1807 vma->vm_ops = &vfio_pci_mmap_ops;
1808
1809 return 0;
1810 }
1811 EXPORT_SYMBOL_GPL(vfio_pci_core_mmap);
1812
vfio_pci_core_request(struct vfio_device * core_vdev,unsigned int count)1813 void vfio_pci_core_request(struct vfio_device *core_vdev, unsigned int count)
1814 {
1815 struct vfio_pci_core_device *vdev =
1816 container_of(core_vdev, struct vfio_pci_core_device, vdev);
1817 struct pci_dev *pdev = vdev->pdev;
1818
1819 mutex_lock(&vdev->igate);
1820
1821 if (vdev->req_trigger) {
1822 if (!(count % 10))
1823 pci_notice_ratelimited(pdev,
1824 "Relaying device request to user (#%u)\n",
1825 count);
1826 eventfd_signal(vdev->req_trigger);
1827 } else if (count == 0) {
1828 pci_warn(pdev,
1829 "No device request channel registered, blocked until released by user\n");
1830 }
1831
1832 mutex_unlock(&vdev->igate);
1833 }
1834 EXPORT_SYMBOL_GPL(vfio_pci_core_request);
1835
vfio_pci_validate_vf_token(struct vfio_pci_core_device * vdev,bool vf_token,uuid_t * uuid)1836 static int vfio_pci_validate_vf_token(struct vfio_pci_core_device *vdev,
1837 bool vf_token, uuid_t *uuid)
1838 {
1839 /*
1840 * There's always some degree of trust or collaboration between SR-IOV
1841 * PF and VFs, even if just that the PF hosts the SR-IOV capability and
1842 * can disrupt VFs with a reset, but often the PF has more explicit
1843 * access to deny service to the VF or access data passed through the
1844 * VF. We therefore require an opt-in via a shared VF token (UUID) to
1845 * represent this trust. This both prevents that a VF driver might
1846 * assume the PF driver is a trusted, in-kernel driver, and also that
1847 * a PF driver might be replaced with a rogue driver, unknown to in-use
1848 * VF drivers.
1849 *
1850 * Therefore when presented with a VF, if the PF is a vfio device and
1851 * it is bound to the vfio-pci driver, the user needs to provide a VF
1852 * token to access the device, in the form of appending a vf_token to
1853 * the device name, for example:
1854 *
1855 * "0000:04:10.0 vf_token=bd8d9d2b-5a5f-4f5a-a211-f591514ba1f3"
1856 *
1857 * When presented with a PF which has VFs in use, the user must also
1858 * provide the current VF token to prove collaboration with existing
1859 * VF users. If VFs are not in use, the VF token provided for the PF
1860 * device will act to set the VF token.
1861 *
1862 * If the VF token is provided but unused, an error is generated.
1863 */
1864 if (vdev->pdev->is_virtfn) {
1865 struct vfio_pci_core_device *pf_vdev = vdev->sriov_pf_core_dev;
1866 bool match;
1867
1868 if (!pf_vdev) {
1869 if (!vf_token)
1870 return 0; /* PF is not vfio-pci, no VF token */
1871
1872 pci_info_ratelimited(vdev->pdev,
1873 "VF token incorrectly provided, PF not bound to vfio-pci\n");
1874 return -EINVAL;
1875 }
1876
1877 if (!vf_token) {
1878 pci_info_ratelimited(vdev->pdev,
1879 "VF token required to access device\n");
1880 return -EACCES;
1881 }
1882
1883 mutex_lock(&pf_vdev->vf_token->lock);
1884 match = uuid_equal(uuid, &pf_vdev->vf_token->uuid);
1885 mutex_unlock(&pf_vdev->vf_token->lock);
1886
1887 if (!match) {
1888 pci_info_ratelimited(vdev->pdev,
1889 "Incorrect VF token provided for device\n");
1890 return -EACCES;
1891 }
1892 } else if (vdev->vf_token) {
1893 mutex_lock(&vdev->vf_token->lock);
1894 if (vdev->vf_token->users) {
1895 if (!vf_token) {
1896 mutex_unlock(&vdev->vf_token->lock);
1897 pci_info_ratelimited(vdev->pdev,
1898 "VF token required to access device\n");
1899 return -EACCES;
1900 }
1901
1902 if (!uuid_equal(uuid, &vdev->vf_token->uuid)) {
1903 mutex_unlock(&vdev->vf_token->lock);
1904 pci_info_ratelimited(vdev->pdev,
1905 "Incorrect VF token provided for device\n");
1906 return -EACCES;
1907 }
1908 } else if (vf_token) {
1909 uuid_copy(&vdev->vf_token->uuid, uuid);
1910 }
1911
1912 mutex_unlock(&vdev->vf_token->lock);
1913 } else if (vf_token) {
1914 pci_info_ratelimited(vdev->pdev,
1915 "VF token incorrectly provided, not a PF or VF\n");
1916 return -EINVAL;
1917 }
1918
1919 return 0;
1920 }
1921
1922 #define VF_TOKEN_ARG "vf_token="
1923
vfio_pci_core_match(struct vfio_device * core_vdev,char * buf)1924 int vfio_pci_core_match(struct vfio_device *core_vdev, char *buf)
1925 {
1926 struct vfio_pci_core_device *vdev =
1927 container_of(core_vdev, struct vfio_pci_core_device, vdev);
1928 bool vf_token = false;
1929 uuid_t uuid;
1930 int ret;
1931
1932 if (strncmp(pci_name(vdev->pdev), buf, strlen(pci_name(vdev->pdev))))
1933 return 0; /* No match */
1934
1935 if (strlen(buf) > strlen(pci_name(vdev->pdev))) {
1936 buf += strlen(pci_name(vdev->pdev));
1937
1938 if (*buf != ' ')
1939 return 0; /* No match: non-whitespace after name */
1940
1941 while (*buf) {
1942 if (*buf == ' ') {
1943 buf++;
1944 continue;
1945 }
1946
1947 if (!vf_token && !strncmp(buf, VF_TOKEN_ARG,
1948 strlen(VF_TOKEN_ARG))) {
1949 buf += strlen(VF_TOKEN_ARG);
1950
1951 if (strlen(buf) < UUID_STRING_LEN)
1952 return -EINVAL;
1953
1954 ret = uuid_parse(buf, &uuid);
1955 if (ret)
1956 return ret;
1957
1958 vf_token = true;
1959 buf += UUID_STRING_LEN;
1960 } else {
1961 /* Unknown/duplicate option */
1962 return -EINVAL;
1963 }
1964 }
1965 }
1966
1967 ret = vfio_pci_validate_vf_token(vdev, vf_token, &uuid);
1968 if (ret)
1969 return ret;
1970
1971 return 1; /* Match */
1972 }
1973 EXPORT_SYMBOL_GPL(vfio_pci_core_match);
1974
vfio_pci_bus_notifier(struct notifier_block * nb,unsigned long action,void * data)1975 static int vfio_pci_bus_notifier(struct notifier_block *nb,
1976 unsigned long action, void *data)
1977 {
1978 struct vfio_pci_core_device *vdev = container_of(nb,
1979 struct vfio_pci_core_device, nb);
1980 struct device *dev = data;
1981 struct pci_dev *pdev = to_pci_dev(dev);
1982 struct pci_dev *physfn = pci_physfn(pdev);
1983
1984 if (action == BUS_NOTIFY_ADD_DEVICE &&
1985 pdev->is_virtfn && physfn == vdev->pdev) {
1986 pci_info(vdev->pdev, "Captured SR-IOV VF %s driver_override\n",
1987 pci_name(pdev));
1988 pdev->driver_override = kasprintf(GFP_KERNEL, "%s",
1989 vdev->vdev.ops->name);
1990 WARN_ON(!pdev->driver_override);
1991 } else if (action == BUS_NOTIFY_BOUND_DRIVER &&
1992 pdev->is_virtfn && physfn == vdev->pdev) {
1993 struct pci_driver *drv = pci_dev_driver(pdev);
1994
1995 if (drv && drv != pci_dev_driver(vdev->pdev))
1996 pci_warn(vdev->pdev,
1997 "VF %s bound to driver %s while PF bound to driver %s\n",
1998 pci_name(pdev), drv->name,
1999 pci_dev_driver(vdev->pdev)->name);
2000 }
2001
2002 return 0;
2003 }
2004
vfio_pci_vf_init(struct vfio_pci_core_device * vdev)2005 static int vfio_pci_vf_init(struct vfio_pci_core_device *vdev)
2006 {
2007 struct pci_dev *pdev = vdev->pdev;
2008 struct vfio_pci_core_device *cur;
2009 struct pci_dev *physfn;
2010 int ret;
2011
2012 if (pdev->is_virtfn) {
2013 /*
2014 * If this VF was created by our vfio_pci_core_sriov_configure()
2015 * then we can find the PF vfio_pci_core_device now, and due to
2016 * the locking in pci_disable_sriov() it cannot change until
2017 * this VF device driver is removed.
2018 */
2019 physfn = pci_physfn(vdev->pdev);
2020 mutex_lock(&vfio_pci_sriov_pfs_mutex);
2021 list_for_each_entry(cur, &vfio_pci_sriov_pfs, sriov_pfs_item) {
2022 if (cur->pdev == physfn) {
2023 vdev->sriov_pf_core_dev = cur;
2024 break;
2025 }
2026 }
2027 mutex_unlock(&vfio_pci_sriov_pfs_mutex);
2028 return 0;
2029 }
2030
2031 /* Not a SRIOV PF */
2032 if (!pdev->is_physfn)
2033 return 0;
2034
2035 vdev->vf_token = kzalloc(sizeof(*vdev->vf_token), GFP_KERNEL);
2036 if (!vdev->vf_token)
2037 return -ENOMEM;
2038
2039 mutex_init(&vdev->vf_token->lock);
2040 uuid_gen(&vdev->vf_token->uuid);
2041
2042 vdev->nb.notifier_call = vfio_pci_bus_notifier;
2043 ret = bus_register_notifier(&pci_bus_type, &vdev->nb);
2044 if (ret) {
2045 kfree(vdev->vf_token);
2046 return ret;
2047 }
2048 return 0;
2049 }
2050
vfio_pci_vf_uninit(struct vfio_pci_core_device * vdev)2051 static void vfio_pci_vf_uninit(struct vfio_pci_core_device *vdev)
2052 {
2053 if (!vdev->vf_token)
2054 return;
2055
2056 bus_unregister_notifier(&pci_bus_type, &vdev->nb);
2057 WARN_ON(vdev->vf_token->users);
2058 mutex_destroy(&vdev->vf_token->lock);
2059 kfree(vdev->vf_token);
2060 }
2061
vfio_pci_vga_init(struct vfio_pci_core_device * vdev)2062 static int vfio_pci_vga_init(struct vfio_pci_core_device *vdev)
2063 {
2064 struct pci_dev *pdev = vdev->pdev;
2065 int ret;
2066
2067 if (!vfio_pci_is_vga(pdev))
2068 return 0;
2069
2070 ret = aperture_remove_conflicting_pci_devices(pdev, vdev->vdev.ops->name);
2071 if (ret)
2072 return ret;
2073
2074 ret = vga_client_register(pdev, vfio_pci_set_decode);
2075 if (ret)
2076 return ret;
2077 vga_set_legacy_decoding(pdev, vfio_pci_set_decode(pdev, false));
2078 return 0;
2079 }
2080
vfio_pci_vga_uninit(struct vfio_pci_core_device * vdev)2081 static void vfio_pci_vga_uninit(struct vfio_pci_core_device *vdev)
2082 {
2083 struct pci_dev *pdev = vdev->pdev;
2084
2085 if (!vfio_pci_is_vga(pdev))
2086 return;
2087 vga_client_unregister(pdev);
2088 vga_set_legacy_decoding(pdev, VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM |
2089 VGA_RSRC_LEGACY_IO |
2090 VGA_RSRC_LEGACY_MEM);
2091 }
2092
vfio_pci_core_init_dev(struct vfio_device * core_vdev)2093 int vfio_pci_core_init_dev(struct vfio_device *core_vdev)
2094 {
2095 struct vfio_pci_core_device *vdev =
2096 container_of(core_vdev, struct vfio_pci_core_device, vdev);
2097
2098 vdev->pdev = to_pci_dev(core_vdev->dev);
2099 vdev->irq_type = VFIO_PCI_NUM_IRQS;
2100 mutex_init(&vdev->igate);
2101 spin_lock_init(&vdev->irqlock);
2102 mutex_init(&vdev->ioeventfds_lock);
2103 INIT_LIST_HEAD(&vdev->dummy_resources_list);
2104 INIT_LIST_HEAD(&vdev->ioeventfds_list);
2105 INIT_LIST_HEAD(&vdev->sriov_pfs_item);
2106 init_rwsem(&vdev->memory_lock);
2107 xa_init(&vdev->ctx);
2108
2109 return 0;
2110 }
2111 EXPORT_SYMBOL_GPL(vfio_pci_core_init_dev);
2112
vfio_pci_core_release_dev(struct vfio_device * core_vdev)2113 void vfio_pci_core_release_dev(struct vfio_device *core_vdev)
2114 {
2115 struct vfio_pci_core_device *vdev =
2116 container_of(core_vdev, struct vfio_pci_core_device, vdev);
2117
2118 mutex_destroy(&vdev->igate);
2119 mutex_destroy(&vdev->ioeventfds_lock);
2120 kfree(vdev->region);
2121 kfree(vdev->pm_save);
2122 }
2123 EXPORT_SYMBOL_GPL(vfio_pci_core_release_dev);
2124
vfio_pci_core_register_device(struct vfio_pci_core_device * vdev)2125 int vfio_pci_core_register_device(struct vfio_pci_core_device *vdev)
2126 {
2127 struct pci_dev *pdev = vdev->pdev;
2128 struct device *dev = &pdev->dev;
2129 int ret;
2130
2131 /* Drivers must set the vfio_pci_core_device to their drvdata */
2132 if (WARN_ON(vdev != dev_get_drvdata(dev)))
2133 return -EINVAL;
2134
2135 if (pdev->hdr_type != PCI_HEADER_TYPE_NORMAL)
2136 return -EINVAL;
2137
2138 if (vdev->vdev.mig_ops) {
2139 if (!(vdev->vdev.mig_ops->migration_get_state &&
2140 vdev->vdev.mig_ops->migration_set_state &&
2141 vdev->vdev.mig_ops->migration_get_data_size) ||
2142 !(vdev->vdev.migration_flags & VFIO_MIGRATION_STOP_COPY))
2143 return -EINVAL;
2144 }
2145
2146 if (vdev->vdev.log_ops && !(vdev->vdev.log_ops->log_start &&
2147 vdev->vdev.log_ops->log_stop &&
2148 vdev->vdev.log_ops->log_read_and_clear))
2149 return -EINVAL;
2150
2151 /*
2152 * Prevent binding to PFs with VFs enabled, the VFs might be in use
2153 * by the host or other users. We cannot capture the VFs if they
2154 * already exist, nor can we track VF users. Disabling SR-IOV here
2155 * would initiate removing the VFs, which would unbind the driver,
2156 * which is prone to blocking if that VF is also in use by vfio-pci.
2157 * Just reject these PFs and let the user sort it out.
2158 */
2159 if (pci_num_vf(pdev)) {
2160 pci_warn(pdev, "Cannot bind to PF with SR-IOV enabled\n");
2161 return -EBUSY;
2162 }
2163
2164 if (pci_is_root_bus(pdev->bus)) {
2165 ret = vfio_assign_device_set(&vdev->vdev, vdev);
2166 } else if (!pci_probe_reset_slot(pdev->slot)) {
2167 ret = vfio_assign_device_set(&vdev->vdev, pdev->slot);
2168 } else {
2169 /*
2170 * If there is no slot reset support for this device, the whole
2171 * bus needs to be grouped together to support bus-wide resets.
2172 */
2173 ret = vfio_assign_device_set(&vdev->vdev, pdev->bus);
2174 }
2175
2176 if (ret)
2177 return ret;
2178 ret = vfio_pci_vf_init(vdev);
2179 if (ret)
2180 return ret;
2181 ret = vfio_pci_vga_init(vdev);
2182 if (ret)
2183 goto out_vf;
2184
2185 vfio_pci_probe_power_state(vdev);
2186
2187 /*
2188 * pci-core sets the device power state to an unknown value at
2189 * bootup and after being removed from a driver. The only
2190 * transition it allows from this unknown state is to D0, which
2191 * typically happens when a driver calls pci_enable_device().
2192 * We're not ready to enable the device yet, but we do want to
2193 * be able to get to D3. Therefore first do a D0 transition
2194 * before enabling runtime PM.
2195 */
2196 vfio_pci_set_power_state(vdev, PCI_D0);
2197
2198 dev->driver->pm = &vfio_pci_core_pm_ops;
2199 pm_runtime_allow(dev);
2200 if (!disable_idle_d3)
2201 pm_runtime_put(dev);
2202
2203 ret = vfio_register_group_dev(&vdev->vdev);
2204 if (ret)
2205 goto out_power;
2206 return 0;
2207
2208 out_power:
2209 if (!disable_idle_d3)
2210 pm_runtime_get_noresume(dev);
2211
2212 pm_runtime_forbid(dev);
2213 out_vf:
2214 vfio_pci_vf_uninit(vdev);
2215 return ret;
2216 }
2217 EXPORT_SYMBOL_GPL(vfio_pci_core_register_device);
2218
vfio_pci_core_unregister_device(struct vfio_pci_core_device * vdev)2219 void vfio_pci_core_unregister_device(struct vfio_pci_core_device *vdev)
2220 {
2221 vfio_pci_core_sriov_configure(vdev, 0);
2222
2223 vfio_unregister_group_dev(&vdev->vdev);
2224
2225 vfio_pci_vf_uninit(vdev);
2226 vfio_pci_vga_uninit(vdev);
2227
2228 if (!disable_idle_d3)
2229 pm_runtime_get_noresume(&vdev->pdev->dev);
2230
2231 pm_runtime_forbid(&vdev->pdev->dev);
2232 }
2233 EXPORT_SYMBOL_GPL(vfio_pci_core_unregister_device);
2234
vfio_pci_core_aer_err_detected(struct pci_dev * pdev,pci_channel_state_t state)2235 pci_ers_result_t vfio_pci_core_aer_err_detected(struct pci_dev *pdev,
2236 pci_channel_state_t state)
2237 {
2238 struct vfio_pci_core_device *vdev = dev_get_drvdata(&pdev->dev);
2239
2240 mutex_lock(&vdev->igate);
2241
2242 if (vdev->err_trigger)
2243 eventfd_signal(vdev->err_trigger);
2244
2245 mutex_unlock(&vdev->igate);
2246
2247 return PCI_ERS_RESULT_CAN_RECOVER;
2248 }
2249 EXPORT_SYMBOL_GPL(vfio_pci_core_aer_err_detected);
2250
vfio_pci_core_sriov_configure(struct vfio_pci_core_device * vdev,int nr_virtfn)2251 int vfio_pci_core_sriov_configure(struct vfio_pci_core_device *vdev,
2252 int nr_virtfn)
2253 {
2254 struct pci_dev *pdev = vdev->pdev;
2255 int ret = 0;
2256
2257 device_lock_assert(&pdev->dev);
2258
2259 if (nr_virtfn) {
2260 mutex_lock(&vfio_pci_sriov_pfs_mutex);
2261 /*
2262 * The thread that adds the vdev to the list is the only thread
2263 * that gets to call pci_enable_sriov() and we will only allow
2264 * it to be called once without going through
2265 * pci_disable_sriov()
2266 */
2267 if (!list_empty(&vdev->sriov_pfs_item)) {
2268 ret = -EINVAL;
2269 goto out_unlock;
2270 }
2271 list_add_tail(&vdev->sriov_pfs_item, &vfio_pci_sriov_pfs);
2272 mutex_unlock(&vfio_pci_sriov_pfs_mutex);
2273
2274 /*
2275 * The PF power state should always be higher than the VF power
2276 * state. The PF can be in low power state either with runtime
2277 * power management (when there is no user) or PCI_PM_CTRL
2278 * register write by the user. If PF is in the low power state,
2279 * then change the power state to D0 first before enabling
2280 * SR-IOV. Also, this function can be called at any time, and
2281 * userspace PCI_PM_CTRL write can race against this code path,
2282 * so protect the same with 'memory_lock'.
2283 */
2284 ret = pm_runtime_resume_and_get(&pdev->dev);
2285 if (ret)
2286 goto out_del;
2287
2288 down_write(&vdev->memory_lock);
2289 vfio_pci_set_power_state(vdev, PCI_D0);
2290 ret = pci_enable_sriov(pdev, nr_virtfn);
2291 up_write(&vdev->memory_lock);
2292 if (ret) {
2293 pm_runtime_put(&pdev->dev);
2294 goto out_del;
2295 }
2296 return nr_virtfn;
2297 }
2298
2299 if (pci_num_vf(pdev)) {
2300 pci_disable_sriov(pdev);
2301 pm_runtime_put(&pdev->dev);
2302 }
2303
2304 out_del:
2305 mutex_lock(&vfio_pci_sriov_pfs_mutex);
2306 list_del_init(&vdev->sriov_pfs_item);
2307 out_unlock:
2308 mutex_unlock(&vfio_pci_sriov_pfs_mutex);
2309 return ret;
2310 }
2311 EXPORT_SYMBOL_GPL(vfio_pci_core_sriov_configure);
2312
2313 const struct pci_error_handlers vfio_pci_core_err_handlers = {
2314 .error_detected = vfio_pci_core_aer_err_detected,
2315 };
2316 EXPORT_SYMBOL_GPL(vfio_pci_core_err_handlers);
2317
vfio_dev_in_groups(struct vfio_device * vdev,struct vfio_pci_group_info * groups)2318 static bool vfio_dev_in_groups(struct vfio_device *vdev,
2319 struct vfio_pci_group_info *groups)
2320 {
2321 unsigned int i;
2322
2323 if (!groups)
2324 return false;
2325
2326 for (i = 0; i < groups->count; i++)
2327 if (vfio_file_has_dev(groups->files[i], vdev))
2328 return true;
2329 return false;
2330 }
2331
vfio_pci_is_device_in_set(struct pci_dev * pdev,void * data)2332 static int vfio_pci_is_device_in_set(struct pci_dev *pdev, void *data)
2333 {
2334 struct vfio_device_set *dev_set = data;
2335
2336 return vfio_find_device_in_devset(dev_set, &pdev->dev) ? 0 : -ENODEV;
2337 }
2338
2339 /*
2340 * vfio-core considers a group to be viable and will create a vfio_device even
2341 * if some devices are bound to drivers like pci-stub or pcieport. Here we
2342 * require all PCI devices to be inside our dev_set since that ensures they stay
2343 * put and that every driver controlling the device can co-ordinate with the
2344 * device reset.
2345 *
2346 * Returns the pci_dev to pass to pci_reset_bus() if every PCI device to be
2347 * reset is inside the dev_set, and pci_reset_bus() can succeed. NULL otherwise.
2348 */
2349 static struct pci_dev *
vfio_pci_dev_set_resettable(struct vfio_device_set * dev_set)2350 vfio_pci_dev_set_resettable(struct vfio_device_set *dev_set)
2351 {
2352 struct pci_dev *pdev;
2353
2354 lockdep_assert_held(&dev_set->lock);
2355
2356 /*
2357 * By definition all PCI devices in the dev_set share the same PCI
2358 * reset, so any pci_dev will have the same outcomes for
2359 * pci_probe_reset_*() and pci_reset_bus().
2360 */
2361 pdev = list_first_entry(&dev_set->device_list,
2362 struct vfio_pci_core_device,
2363 vdev.dev_set_list)->pdev;
2364
2365 /* pci_reset_bus() is supported */
2366 if (pci_probe_reset_slot(pdev->slot) && pci_probe_reset_bus(pdev->bus))
2367 return NULL;
2368
2369 if (vfio_pci_for_each_slot_or_bus(pdev, vfio_pci_is_device_in_set,
2370 dev_set,
2371 !pci_probe_reset_slot(pdev->slot)))
2372 return NULL;
2373 return pdev;
2374 }
2375
vfio_pci_dev_set_pm_runtime_get(struct vfio_device_set * dev_set)2376 static int vfio_pci_dev_set_pm_runtime_get(struct vfio_device_set *dev_set)
2377 {
2378 struct vfio_pci_core_device *cur;
2379 int ret;
2380
2381 list_for_each_entry(cur, &dev_set->device_list, vdev.dev_set_list) {
2382 ret = pm_runtime_resume_and_get(&cur->pdev->dev);
2383 if (ret)
2384 goto unwind;
2385 }
2386
2387 return 0;
2388
2389 unwind:
2390 list_for_each_entry_continue_reverse(cur, &dev_set->device_list,
2391 vdev.dev_set_list)
2392 pm_runtime_put(&cur->pdev->dev);
2393
2394 return ret;
2395 }
2396
vfio_pci_dev_set_hot_reset(struct vfio_device_set * dev_set,struct vfio_pci_group_info * groups,struct iommufd_ctx * iommufd_ctx)2397 static int vfio_pci_dev_set_hot_reset(struct vfio_device_set *dev_set,
2398 struct vfio_pci_group_info *groups,
2399 struct iommufd_ctx *iommufd_ctx)
2400 {
2401 struct vfio_pci_core_device *vdev;
2402 struct pci_dev *pdev;
2403 int ret;
2404
2405 mutex_lock(&dev_set->lock);
2406
2407 pdev = vfio_pci_dev_set_resettable(dev_set);
2408 if (!pdev) {
2409 ret = -EINVAL;
2410 goto err_unlock;
2411 }
2412
2413 /*
2414 * Some of the devices in the dev_set can be in the runtime suspended
2415 * state. Increment the usage count for all the devices in the dev_set
2416 * before reset and decrement the same after reset.
2417 */
2418 ret = vfio_pci_dev_set_pm_runtime_get(dev_set);
2419 if (ret)
2420 goto err_unlock;
2421
2422 list_for_each_entry(vdev, &dev_set->device_list, vdev.dev_set_list) {
2423 bool owned;
2424
2425 /*
2426 * Test whether all the affected devices can be reset by the
2427 * user.
2428 *
2429 * If called from a group opened device and the user provides
2430 * a set of groups, all the devices in the dev_set should be
2431 * contained by the set of groups provided by the user.
2432 *
2433 * If called from a cdev opened device and the user provides
2434 * a zero-length array, all the devices in the dev_set must
2435 * be bound to the same iommufd_ctx as the input iommufd_ctx.
2436 * If there is any device that has not been bound to any
2437 * iommufd_ctx yet, check if its iommu_group has any device
2438 * bound to the input iommufd_ctx. Such devices can be
2439 * considered owned by the input iommufd_ctx as the device
2440 * cannot be owned by another iommufd_ctx when its iommu_group
2441 * is owned.
2442 *
2443 * Otherwise, reset is not allowed.
2444 */
2445 if (iommufd_ctx) {
2446 int devid = vfio_iommufd_get_dev_id(&vdev->vdev,
2447 iommufd_ctx);
2448
2449 owned = (devid > 0 || devid == -ENOENT);
2450 } else {
2451 owned = vfio_dev_in_groups(&vdev->vdev, groups);
2452 }
2453
2454 if (!owned) {
2455 ret = -EINVAL;
2456 break;
2457 }
2458
2459 /*
2460 * Take the memory write lock for each device and zap BAR
2461 * mappings to prevent the user accessing the device while in
2462 * reset. Locking multiple devices is prone to deadlock,
2463 * runaway and unwind if we hit contention.
2464 */
2465 if (!down_write_trylock(&vdev->memory_lock)) {
2466 ret = -EBUSY;
2467 break;
2468 }
2469
2470 vfio_pci_zap_bars(vdev);
2471 }
2472
2473 if (!list_entry_is_head(vdev,
2474 &dev_set->device_list, vdev.dev_set_list)) {
2475 vdev = list_prev_entry(vdev, vdev.dev_set_list);
2476 goto err_undo;
2477 }
2478
2479 /*
2480 * The pci_reset_bus() will reset all the devices in the bus.
2481 * The power state can be non-D0 for some of the devices in the bus.
2482 * For these devices, the pci_reset_bus() will internally set
2483 * the power state to D0 without vfio driver involvement.
2484 * For the devices which have NoSoftRst-, the reset function can
2485 * cause the PCI config space reset without restoring the original
2486 * state (saved locally in 'vdev->pm_save').
2487 */
2488 list_for_each_entry(vdev, &dev_set->device_list, vdev.dev_set_list)
2489 vfio_pci_set_power_state(vdev, PCI_D0);
2490
2491 ret = pci_reset_bus(pdev);
2492
2493 vdev = list_last_entry(&dev_set->device_list,
2494 struct vfio_pci_core_device, vdev.dev_set_list);
2495
2496 err_undo:
2497 list_for_each_entry_from_reverse(vdev, &dev_set->device_list,
2498 vdev.dev_set_list)
2499 up_write(&vdev->memory_lock);
2500
2501 list_for_each_entry(vdev, &dev_set->device_list, vdev.dev_set_list)
2502 pm_runtime_put(&vdev->pdev->dev);
2503
2504 err_unlock:
2505 mutex_unlock(&dev_set->lock);
2506 return ret;
2507 }
2508
vfio_pci_dev_set_needs_reset(struct vfio_device_set * dev_set)2509 static bool vfio_pci_dev_set_needs_reset(struct vfio_device_set *dev_set)
2510 {
2511 struct vfio_pci_core_device *cur;
2512 bool needs_reset = false;
2513
2514 /* No other VFIO device in the set can be open. */
2515 if (vfio_device_set_open_count(dev_set) > 1)
2516 return false;
2517
2518 list_for_each_entry(cur, &dev_set->device_list, vdev.dev_set_list)
2519 needs_reset |= cur->needs_reset;
2520 return needs_reset;
2521 }
2522
2523 /*
2524 * If a bus or slot reset is available for the provided dev_set and:
2525 * - All of the devices affected by that bus or slot reset are unused
2526 * - At least one of the affected devices is marked dirty via
2527 * needs_reset (such as by lack of FLR support)
2528 * Then attempt to perform that bus or slot reset.
2529 */
vfio_pci_dev_set_try_reset(struct vfio_device_set * dev_set)2530 static void vfio_pci_dev_set_try_reset(struct vfio_device_set *dev_set)
2531 {
2532 struct vfio_pci_core_device *cur;
2533 struct pci_dev *pdev;
2534 bool reset_done = false;
2535
2536 if (!vfio_pci_dev_set_needs_reset(dev_set))
2537 return;
2538
2539 pdev = vfio_pci_dev_set_resettable(dev_set);
2540 if (!pdev)
2541 return;
2542
2543 /*
2544 * Some of the devices in the bus can be in the runtime suspended
2545 * state. Increment the usage count for all the devices in the dev_set
2546 * before reset and decrement the same after reset.
2547 */
2548 if (!disable_idle_d3 && vfio_pci_dev_set_pm_runtime_get(dev_set))
2549 return;
2550
2551 if (!pci_reset_bus(pdev))
2552 reset_done = true;
2553
2554 list_for_each_entry(cur, &dev_set->device_list, vdev.dev_set_list) {
2555 if (reset_done)
2556 cur->needs_reset = false;
2557
2558 if (!disable_idle_d3)
2559 pm_runtime_put(&cur->pdev->dev);
2560 }
2561 }
2562
vfio_pci_core_set_params(bool is_nointxmask,bool is_disable_vga,bool is_disable_idle_d3)2563 void vfio_pci_core_set_params(bool is_nointxmask, bool is_disable_vga,
2564 bool is_disable_idle_d3)
2565 {
2566 nointxmask = is_nointxmask;
2567 disable_vga = is_disable_vga;
2568 disable_idle_d3 = is_disable_idle_d3;
2569 }
2570 EXPORT_SYMBOL_GPL(vfio_pci_core_set_params);
2571
vfio_pci_core_cleanup(void)2572 static void vfio_pci_core_cleanup(void)
2573 {
2574 vfio_pci_uninit_perm_bits();
2575 }
2576
vfio_pci_core_init(void)2577 static int __init vfio_pci_core_init(void)
2578 {
2579 /* Allocate shared config space permission data used by all devices */
2580 return vfio_pci_init_perm_bits();
2581 }
2582
2583 module_init(vfio_pci_core_init);
2584 module_exit(vfio_pci_core_cleanup);
2585
2586 MODULE_LICENSE("GPL v2");
2587 MODULE_AUTHOR(DRIVER_AUTHOR);
2588 MODULE_DESCRIPTION(DRIVER_DESC);
2589