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Merge tag 'block-5.11-2021-01-10' of git://git.kernel.dk/linux-block
[linux/fpc-iii.git] / drivers / vfio / pci / vfio_pci.c
blob706de3ef94bbffc02073feba3f47bcad0c412662
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/device.h>
14 #include <linux/eventfd.h>
15 #include <linux/file.h>
16 #include <linux/interrupt.h>
17 #include <linux/iommu.h>
18 #include <linux/module.h>
19 #include <linux/mutex.h>
20 #include <linux/notifier.h>
21 #include <linux/pci.h>
22 #include <linux/pm_runtime.h>
23 #include <linux/slab.h>
24 #include <linux/types.h>
25 #include <linux/uaccess.h>
26 #include <linux/vfio.h>
27 #include <linux/vgaarb.h>
28 #include <linux/nospec.h>
29 #include <linux/sched/mm.h>
30
31 #include "vfio_pci_private.h"
32
33 #define DRIVER_VERSION "0.2"
34 #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
35 #define DRIVER_DESC "VFIO PCI - User Level meta-driver"
36
37 static char ids[1024] __initdata;
38 module_param_string(ids, ids, sizeof(ids), 0);
39 MODULE_PARM_DESC(ids, "Initial PCI IDs to add to the vfio driver, format is \"vendor:device[:subvendor[:subdevice[:class[:class_mask]]]]\" and multiple comma separated entries can be specified");
40
41 static bool nointxmask;
42 module_param_named(nointxmask, nointxmask, bool, S_IRUGO | S_IWUSR);
43 MODULE_PARM_DESC(nointxmask,
44 "Disable support for PCI 2.3 style INTx masking. If this resolves problems for specific devices, report lspci -vvvxxx to linux-pci@vger.kernel.org so the device can be fixed automatically via the broken_intx_masking flag.");
45
46 #ifdef CONFIG_VFIO_PCI_VGA
47 static bool disable_vga;
48 module_param(disable_vga, bool, S_IRUGO);
49 MODULE_PARM_DESC(disable_vga, "Disable VGA resource access through vfio-pci");
50 #endif
51
52 static bool disable_idle_d3;
53 module_param(disable_idle_d3, bool, S_IRUGO | S_IWUSR);
54 MODULE_PARM_DESC(disable_idle_d3,
55 "Disable using the PCI D3 low power state for idle, unused devices");
56
57 static bool enable_sriov;
58 #ifdef CONFIG_PCI_IOV
59 module_param(enable_sriov, bool, 0644);
60 MODULE_PARM_DESC(enable_sriov, "Enable support for SR-IOV configuration. Enabling SR-IOV on a PF typically requires support of the userspace PF driver, enabling VFs without such support may result in non-functional VFs or PF.");
61 #endif
62
63 static bool disable_denylist;
64 module_param(disable_denylist, bool, 0444);
65 MODULE_PARM_DESC(disable_denylist, "Disable use of device denylist. Disabling the denylist allows binding to devices with known errata that may lead to exploitable stability or security issues when accessed by untrusted users.");
66
67 static inline bool vfio_vga_disabled(void)
68 {
69 #ifdef CONFIG_VFIO_PCI_VGA
70 return disable_vga;
71 #else
72 return true;
73 #endif
74 }
75
76 static bool vfio_pci_dev_in_denylist(struct pci_dev *pdev)
77 {
78 switch (pdev->vendor) {
79 case PCI_VENDOR_ID_INTEL:
80 switch (pdev->device) {
81 case PCI_DEVICE_ID_INTEL_QAT_C3XXX:
82 case PCI_DEVICE_ID_INTEL_QAT_C3XXX_VF:
83 case PCI_DEVICE_ID_INTEL_QAT_C62X:
84 case PCI_DEVICE_ID_INTEL_QAT_C62X_VF:
85 case PCI_DEVICE_ID_INTEL_QAT_DH895XCC:
86 case PCI_DEVICE_ID_INTEL_QAT_DH895XCC_VF:
87 return true;
88 default:
89 return false;
90 }
91 }
92
93 return false;
94 }
95
96 static bool vfio_pci_is_denylisted(struct pci_dev *pdev)
97 {
98 if (!vfio_pci_dev_in_denylist(pdev))
99 return false;
100
101 if (disable_denylist) {
102 pci_warn(pdev,
103 "device denylist disabled - allowing device %04x:%04x.\n",
104 pdev->vendor, pdev->device);
105 return false;
106 }
107
108 pci_warn(pdev, "%04x:%04x exists in vfio-pci device denylist, driver probing disallowed.\n",
109 pdev->vendor, pdev->device);
110
111 return true;
112 }
113
114 /*
115 * Our VGA arbiter participation is limited since we don't know anything
116 * about the device itself. However, if the device is the only VGA device
117 * downstream of a bridge and VFIO VGA support is disabled, then we can
118 * safely return legacy VGA IO and memory as not decoded since the user
119 * has no way to get to it and routing can be disabled externally at the
120 * bridge.
121 */
122 static unsigned int vfio_pci_set_vga_decode(void *opaque, bool single_vga)
123 {
124 struct vfio_pci_device *vdev = opaque;
125 struct pci_dev *tmp = NULL, *pdev = vdev->pdev;
126 unsigned char max_busnr;
127 unsigned int decodes;
128
129 if (single_vga || !vfio_vga_disabled() || pci_is_root_bus(pdev->bus))
130 return VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM |
131 VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM;
132
133 max_busnr = pci_bus_max_busnr(pdev->bus);
134 decodes = VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM;
135
136 while ((tmp = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, tmp)) != NULL) {
137 if (tmp == pdev ||
138 pci_domain_nr(tmp->bus) != pci_domain_nr(pdev->bus) ||
139 pci_is_root_bus(tmp->bus))
140 continue;
141
142 if (tmp->bus->number >= pdev->bus->number &&
143 tmp->bus->number <= max_busnr) {
144 pci_dev_put(tmp);
145 decodes |= VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM;
146 break;
147 }
148 }
149
150 return decodes;
151 }
152
153 static inline bool vfio_pci_is_vga(struct pci_dev *pdev)
154 {
155 return (pdev->class >> 8) == PCI_CLASS_DISPLAY_VGA;
156 }
157
158 static void vfio_pci_probe_mmaps(struct vfio_pci_device *vdev)
159 {
160 struct resource *res;
161 int i;
162 struct vfio_pci_dummy_resource *dummy_res;
163
164 for (i = 0; i < PCI_STD_NUM_BARS; i++) {
165 int bar = i + PCI_STD_RESOURCES;
166
167 res = &vdev->pdev->resource[bar];
168
169 if (!IS_ENABLED(CONFIG_VFIO_PCI_MMAP))
170 goto no_mmap;
171
172 if (!(res->flags & IORESOURCE_MEM))
173 goto no_mmap;
174
175 /*
176 * The PCI core shouldn't set up a resource with a
177 * type but zero size. But there may be bugs that
178 * cause us to do that.
179 */
180 if (!resource_size(res))
181 goto no_mmap;
182
183 if (resource_size(res) >= PAGE_SIZE) {
184 vdev->bar_mmap_supported[bar] = true;
185 continue;
186 }
187
188 if (!(res->start & ~PAGE_MASK)) {
189 /*
190 * Add a dummy resource to reserve the remainder
191 * of the exclusive page in case that hot-add
192 * device's bar is assigned into it.
193 */
194 dummy_res = kzalloc(sizeof(*dummy_res), GFP_KERNEL);
195 if (dummy_res == NULL)
196 goto no_mmap;
197
198 dummy_res->resource.name = "vfio sub-page reserved";
199 dummy_res->resource.start = res->end + 1;
200 dummy_res->resource.end = res->start + PAGE_SIZE - 1;
201 dummy_res->resource.flags = res->flags;
202 if (request_resource(res->parent,
203 &dummy_res->resource)) {
204 kfree(dummy_res);
205 goto no_mmap;
206 }
207 dummy_res->index = bar;
208 list_add(&dummy_res->res_next,
209 &vdev->dummy_resources_list);
210 vdev->bar_mmap_supported[bar] = true;
211 continue;
212 }
213 /*
214 * Here we don't handle the case when the BAR is not page
215 * aligned because we can't expect the BAR will be
216 * assigned into the same location in a page in guest
217 * when we passthrough the BAR. And it's hard to access
218 * this BAR in userspace because we have no way to get
219 * the BAR's location in a page.
220 */
221 no_mmap:
222 vdev->bar_mmap_supported[bar] = false;
223 }
224 }
225
226 static void vfio_pci_try_bus_reset(struct vfio_pci_device *vdev);
227 static void vfio_pci_disable(struct vfio_pci_device *vdev);
228 static int vfio_pci_try_zap_and_vma_lock_cb(struct pci_dev *pdev, void *data);
229
230 /*
231 * INTx masking requires the ability to disable INTx signaling via PCI_COMMAND
232 * _and_ the ability detect when the device is asserting INTx via PCI_STATUS.
233 * If a device implements the former but not the latter we would typically
234 * expect broken_intx_masking be set and require an exclusive interrupt.
235 * However since we do have control of the device's ability to assert INTx,
236 * we can instead pretend that the device does not implement INTx, virtualizing
237 * the pin register to report zero and maintaining DisINTx set on the host.
238 */
239 static bool vfio_pci_nointx(struct pci_dev *pdev)
240 {
241 switch (pdev->vendor) {
242 case PCI_VENDOR_ID_INTEL:
243 switch (pdev->device) {
244 /* All i40e (XL710/X710/XXV710) 10/20/25/40GbE NICs */
245 case 0x1572:
246 case 0x1574:
247 case 0x1580 ... 0x1581:
248 case 0x1583 ... 0x158b:
249 case 0x37d0 ... 0x37d2:
250 /* X550 */
251 case 0x1563:
252 return true;
253 default:
254 return false;
255 }
256 }
257
258 return false;
259 }
260
261 static void vfio_pci_probe_power_state(struct vfio_pci_device *vdev)
262 {
263 struct pci_dev *pdev = vdev->pdev;
264 u16 pmcsr;
265
266 if (!pdev->pm_cap)
267 return;
268
269 pci_read_config_word(pdev, pdev->pm_cap + PCI_PM_CTRL, &pmcsr);
270
271 vdev->needs_pm_restore = !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET);
272 }
273
274 /*
275 * pci_set_power_state() wrapper handling devices which perform a soft reset on
276 * D3->D0 transition. Save state prior to D0/1/2->D3, stash it on the vdev,
277 * restore when returned to D0. Saved separately from pci_saved_state for use
278 * by PM capability emulation and separately from pci_dev internal saved state
279 * to avoid it being overwritten and consumed around other resets.
280 */
281 int vfio_pci_set_power_state(struct vfio_pci_device *vdev, pci_power_t state)
282 {
283 struct pci_dev *pdev = vdev->pdev;
284 bool needs_restore = false, needs_save = false;
285 int ret;
286
287 if (vdev->needs_pm_restore) {
288 if (pdev->current_state < PCI_D3hot && state >= PCI_D3hot) {
289 pci_save_state(pdev);
290 needs_save = true;
291 }
292
293 if (pdev->current_state >= PCI_D3hot && state <= PCI_D0)
294 needs_restore = true;
295 }
296
297 ret = pci_set_power_state(pdev, state);
298
299 if (!ret) {
300 /* D3 might be unsupported via quirk, skip unless in D3 */
301 if (needs_save && pdev->current_state >= PCI_D3hot) {
302 vdev->pm_save = pci_store_saved_state(pdev);
303 } else if (needs_restore) {
304 pci_load_and_free_saved_state(pdev, &vdev->pm_save);
305 pci_restore_state(pdev);
306 }
307 }
308
309 return ret;
310 }
311
312 static int vfio_pci_enable(struct vfio_pci_device *vdev)
313 {
314 struct pci_dev *pdev = vdev->pdev;
315 int ret;
316 u16 cmd;
317 u8 msix_pos;
318
319 vfio_pci_set_power_state(vdev, PCI_D0);
320
321 /* Don't allow our initial saved state to include busmaster */
322 pci_clear_master(pdev);
323
324 ret = pci_enable_device(pdev);
325 if (ret)
326 return ret;
327
328 /* If reset fails because of the device lock, fail this path entirely */
329 ret = pci_try_reset_function(pdev);
330 if (ret == -EAGAIN) {
331 pci_disable_device(pdev);
332 return ret;
333 }
334
335 vdev->reset_works = !ret;
336 pci_save_state(pdev);
337 vdev->pci_saved_state = pci_store_saved_state(pdev);
338 if (!vdev->pci_saved_state)
339 pci_dbg(pdev, "%s: Couldn't store saved state\n", __func__);
340
341 if (likely(!nointxmask)) {
342 if (vfio_pci_nointx(pdev)) {
343 pci_info(pdev, "Masking broken INTx support\n");
344 vdev->nointx = true;
345 pci_intx(pdev, 0);
346 } else
347 vdev->pci_2_3 = pci_intx_mask_supported(pdev);
348 }
349
350 pci_read_config_word(pdev, PCI_COMMAND, &cmd);
351 if (vdev->pci_2_3 && (cmd & PCI_COMMAND_INTX_DISABLE)) {
352 cmd &= ~PCI_COMMAND_INTX_DISABLE;
353 pci_write_config_word(pdev, PCI_COMMAND, cmd);
354 }
355
356 ret = vfio_config_init(vdev);
357 if (ret) {
358 kfree(vdev->pci_saved_state);
359 vdev->pci_saved_state = NULL;
360 pci_disable_device(pdev);
361 return ret;
362 }
363
364 msix_pos = pdev->msix_cap;
365 if (msix_pos) {
366 u16 flags;
367 u32 table;
368
369 pci_read_config_word(pdev, msix_pos + PCI_MSIX_FLAGS, &flags);
370 pci_read_config_dword(pdev, msix_pos + PCI_MSIX_TABLE, &table);
371
372 vdev->msix_bar = table & PCI_MSIX_TABLE_BIR;
373 vdev->msix_offset = table & PCI_MSIX_TABLE_OFFSET;
374 vdev->msix_size = ((flags & PCI_MSIX_FLAGS_QSIZE) + 1) * 16;
375 } else
376 vdev->msix_bar = 0xFF;
377
378 if (!vfio_vga_disabled() && vfio_pci_is_vga(pdev))
379 vdev->has_vga = true;
380
381
382 if (vfio_pci_is_vga(pdev) &&
383 pdev->vendor == PCI_VENDOR_ID_INTEL &&
384 IS_ENABLED(CONFIG_VFIO_PCI_IGD)) {
385 ret = vfio_pci_igd_init(vdev);
386 if (ret && ret != -ENODEV) {
387 pci_warn(pdev, "Failed to setup Intel IGD regions\n");
388 goto disable_exit;
389 }
390 }
391
392 if (pdev->vendor == PCI_VENDOR_ID_NVIDIA &&
393 IS_ENABLED(CONFIG_VFIO_PCI_NVLINK2)) {
394 ret = vfio_pci_nvdia_v100_nvlink2_init(vdev);
395 if (ret && ret != -ENODEV) {
396 pci_warn(pdev, "Failed to setup NVIDIA NV2 RAM region\n");
397 goto disable_exit;
398 }
399 }
400
401 if (pdev->vendor == PCI_VENDOR_ID_IBM &&
402 IS_ENABLED(CONFIG_VFIO_PCI_NVLINK2)) {
403 ret = vfio_pci_ibm_npu2_init(vdev);
404 if (ret && ret != -ENODEV) {
405 pci_warn(pdev, "Failed to setup NVIDIA NV2 ATSD region\n");
406 goto disable_exit;
407 }
408 }
409
410 vfio_pci_probe_mmaps(vdev);
411
412 return 0;
413
414 disable_exit:
415 vfio_pci_disable(vdev);
416 return ret;
417 }
418
419 static void vfio_pci_disable(struct vfio_pci_device *vdev)
420 {
421 struct pci_dev *pdev = vdev->pdev;
422 struct vfio_pci_dummy_resource *dummy_res, *tmp;
423 struct vfio_pci_ioeventfd *ioeventfd, *ioeventfd_tmp;
424 int i, bar;
425
426 /* Stop the device from further DMA */
427 pci_clear_master(pdev);
428
429 vfio_pci_set_irqs_ioctl(vdev, VFIO_IRQ_SET_DATA_NONE |
430 VFIO_IRQ_SET_ACTION_TRIGGER,
431 vdev->irq_type, 0, 0, NULL);
432
433 /* Device closed, don't need mutex here */
434 list_for_each_entry_safe(ioeventfd, ioeventfd_tmp,
435 &vdev->ioeventfds_list, next) {
436 vfio_virqfd_disable(&ioeventfd->virqfd);
437 list_del(&ioeventfd->next);
438 kfree(ioeventfd);
439 }
440 vdev->ioeventfds_nr = 0;
441
442 vdev->virq_disabled = false;
443
444 for (i = 0; i < vdev->num_regions; i++)
445 vdev->region[i].ops->release(vdev, &vdev->region[i]);
446
447 vdev->num_regions = 0;
448 kfree(vdev->region);
449 vdev->region = NULL; /* don't krealloc a freed pointer */
450
451 vfio_config_free(vdev);
452
453 for (i = 0; i < PCI_STD_NUM_BARS; i++) {
454 bar = i + PCI_STD_RESOURCES;
455 if (!vdev->barmap[bar])
456 continue;
457 pci_iounmap(pdev, vdev->barmap[bar]);
458 pci_release_selected_regions(pdev, 1 << bar);
459 vdev->barmap[bar] = NULL;
460 }
461
462 list_for_each_entry_safe(dummy_res, tmp,
463 &vdev->dummy_resources_list, res_next) {
464 list_del(&dummy_res->res_next);
465 release_resource(&dummy_res->resource);
466 kfree(dummy_res);
467 }
468
469 vdev->needs_reset = true;
470
471 /*
472 * If we have saved state, restore it. If we can reset the device,
473 * even better. Resetting with current state seems better than
474 * nothing, but saving and restoring current state without reset
475 * is just busy work.
476 */
477 if (pci_load_and_free_saved_state(pdev, &vdev->pci_saved_state)) {
478 pci_info(pdev, "%s: Couldn't reload saved state\n", __func__);
479
480 if (!vdev->reset_works)
481 goto out;
482
483 pci_save_state(pdev);
484 }
485
486 /*
487 * Disable INTx and MSI, presumably to avoid spurious interrupts
488 * during reset. Stolen from pci_reset_function()
489 */
490 pci_write_config_word(pdev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE);
491
492 /*
493 * Try to get the locks ourselves to prevent a deadlock. The
494 * success of this is dependent on being able to lock the device,
495 * which is not always possible.
496 * We can not use the "try" reset interface here, which will
497 * overwrite the previously restored configuration information.
498 */
499 if (vdev->reset_works && pci_cfg_access_trylock(pdev)) {
500 if (device_trylock(&pdev->dev)) {
501 if (!__pci_reset_function_locked(pdev))
502 vdev->needs_reset = false;
503 device_unlock(&pdev->dev);
504 }
505 pci_cfg_access_unlock(pdev);
506 }
507
508 pci_restore_state(pdev);
509 out:
510 pci_disable_device(pdev);
511
512 vfio_pci_try_bus_reset(vdev);
513
514 if (!disable_idle_d3)
515 vfio_pci_set_power_state(vdev, PCI_D3hot);
516 }
517
518 static struct pci_driver vfio_pci_driver;
519
520 static struct vfio_pci_device *get_pf_vdev(struct vfio_pci_device *vdev,
521 struct vfio_device **pf_dev)
522 {
523 struct pci_dev *physfn = pci_physfn(vdev->pdev);
524
525 if (!vdev->pdev->is_virtfn)
526 return NULL;
527
528 *pf_dev = vfio_device_get_from_dev(&physfn->dev);
529 if (!*pf_dev)
530 return NULL;
531
532 if (pci_dev_driver(physfn) != &vfio_pci_driver) {
533 vfio_device_put(*pf_dev);
534 return NULL;
535 }
536
537 return vfio_device_data(*pf_dev);
538 }
539
540 static void vfio_pci_vf_token_user_add(struct vfio_pci_device *vdev, int val)
541 {
542 struct vfio_device *pf_dev;
543 struct vfio_pci_device *pf_vdev = get_pf_vdev(vdev, &pf_dev);
544
545 if (!pf_vdev)
546 return;
547
548 mutex_lock(&pf_vdev->vf_token->lock);
549 pf_vdev->vf_token->users += val;
550 WARN_ON(pf_vdev->vf_token->users < 0);
551 mutex_unlock(&pf_vdev->vf_token->lock);
552
553 vfio_device_put(pf_dev);
554 }
555
556 static void vfio_pci_release(void *device_data)
557 {
558 struct vfio_pci_device *vdev = device_data;
559
560 mutex_lock(&vdev->reflck->lock);
561
562 if (!(--vdev->refcnt)) {
563 vfio_pci_vf_token_user_add(vdev, -1);
564 vfio_spapr_pci_eeh_release(vdev->pdev);
565 vfio_pci_disable(vdev);
566
567 mutex_lock(&vdev->igate);
568 if (vdev->err_trigger) {
569 eventfd_ctx_put(vdev->err_trigger);
570 vdev->err_trigger = NULL;
571 }
572 if (vdev->req_trigger) {
573 eventfd_ctx_put(vdev->req_trigger);
574 vdev->req_trigger = NULL;
575 }
576 mutex_unlock(&vdev->igate);
577 }
578
579 mutex_unlock(&vdev->reflck->lock);
580
581 module_put(THIS_MODULE);
582 }
583
584 static int vfio_pci_open(void *device_data)
585 {
586 struct vfio_pci_device *vdev = device_data;
587 int ret = 0;
588
589 if (!try_module_get(THIS_MODULE))
590 return -ENODEV;
591
592 mutex_lock(&vdev->reflck->lock);
593
594 if (!vdev->refcnt) {
595 ret = vfio_pci_enable(vdev);
596 if (ret)
597 goto error;
598
599 vfio_spapr_pci_eeh_open(vdev->pdev);
600 vfio_pci_vf_token_user_add(vdev, 1);
601 }
602 vdev->refcnt++;
603 error:
604 mutex_unlock(&vdev->reflck->lock);
605 if (ret)
606 module_put(THIS_MODULE);
607 return ret;
608 }
609
610 static int vfio_pci_get_irq_count(struct vfio_pci_device *vdev, int irq_type)
611 {
612 if (irq_type == VFIO_PCI_INTX_IRQ_INDEX) {
613 u8 pin;
614
615 if (!IS_ENABLED(CONFIG_VFIO_PCI_INTX) ||
616 vdev->nointx || vdev->pdev->is_virtfn)
617 return 0;
618
619 pci_read_config_byte(vdev->pdev, PCI_INTERRUPT_PIN, &pin);
620
621 return pin ? 1 : 0;
622 } else if (irq_type == VFIO_PCI_MSI_IRQ_INDEX) {
623 u8 pos;
624 u16 flags;
625
626 pos = vdev->pdev->msi_cap;
627 if (pos) {
628 pci_read_config_word(vdev->pdev,
629 pos + PCI_MSI_FLAGS, &flags);
630 return 1 << ((flags & PCI_MSI_FLAGS_QMASK) >> 1);
631 }
632 } else if (irq_type == VFIO_PCI_MSIX_IRQ_INDEX) {
633 u8 pos;
634 u16 flags;
635
636 pos = vdev->pdev->msix_cap;
637 if (pos) {
638 pci_read_config_word(vdev->pdev,
639 pos + PCI_MSIX_FLAGS, &flags);
640
641 return (flags & PCI_MSIX_FLAGS_QSIZE) + 1;
642 }
643 } else if (irq_type == VFIO_PCI_ERR_IRQ_INDEX) {
644 if (pci_is_pcie(vdev->pdev))
645 return 1;
646 } else if (irq_type == VFIO_PCI_REQ_IRQ_INDEX) {
647 return 1;
648 }
649
650 return 0;
651 }
652
653 static int vfio_pci_count_devs(struct pci_dev *pdev, void *data)
654 {
655 (*(int *)data)++;
656 return 0;
657 }
658
659 struct vfio_pci_fill_info {
660 int max;
661 int cur;
662 struct vfio_pci_dependent_device *devices;
663 };
664
665 static int vfio_pci_fill_devs(struct pci_dev *pdev, void *data)
666 {
667 struct vfio_pci_fill_info *fill = data;
668 struct iommu_group *iommu_group;
669
670 if (fill->cur == fill->max)
671 return -EAGAIN; /* Something changed, try again */
672
673 iommu_group = iommu_group_get(&pdev->dev);
674 if (!iommu_group)
675 return -EPERM; /* Cannot reset non-isolated devices */
676
677 fill->devices[fill->cur].group_id = iommu_group_id(iommu_group);
678 fill->devices[fill->cur].segment = pci_domain_nr(pdev->bus);
679 fill->devices[fill->cur].bus = pdev->bus->number;
680 fill->devices[fill->cur].devfn = pdev->devfn;
681 fill->cur++;
682 iommu_group_put(iommu_group);
683 return 0;
684 }
685
686 struct vfio_pci_group_entry {
687 struct vfio_group *group;
688 int id;
689 };
690
691 struct vfio_pci_group_info {
692 int count;
693 struct vfio_pci_group_entry *groups;
694 };
695
696 static int vfio_pci_validate_devs(struct pci_dev *pdev, void *data)
697 {
698 struct vfio_pci_group_info *info = data;
699 struct iommu_group *group;
700 int id, i;
701
702 group = iommu_group_get(&pdev->dev);
703 if (!group)
704 return -EPERM;
705
706 id = iommu_group_id(group);
707
708 for (i = 0; i < info->count; i++)
709 if (info->groups[i].id == id)
710 break;
711
712 iommu_group_put(group);
713
714 return (i == info->count) ? -EINVAL : 0;
715 }
716
717 static bool vfio_pci_dev_below_slot(struct pci_dev *pdev, struct pci_slot *slot)
718 {
719 for (; pdev; pdev = pdev->bus->self)
720 if (pdev->bus == slot->bus)
721 return (pdev->slot == slot);
722 return false;
723 }
724
725 struct vfio_pci_walk_info {
726 int (*fn)(struct pci_dev *, void *data);
727 void *data;
728 struct pci_dev *pdev;
729 bool slot;
730 int ret;
731 };
732
733 static int vfio_pci_walk_wrapper(struct pci_dev *pdev, void *data)
734 {
735 struct vfio_pci_walk_info *walk = data;
736
737 if (!walk->slot || vfio_pci_dev_below_slot(pdev, walk->pdev->slot))
738 walk->ret = walk->fn(pdev, walk->data);
739
740 return walk->ret;
741 }
742
743 static int vfio_pci_for_each_slot_or_bus(struct pci_dev *pdev,
744 int (*fn)(struct pci_dev *,
745 void *data), void *data,
746 bool slot)
747 {
748 struct vfio_pci_walk_info walk = {
749 .fn = fn, .data = data, .pdev = pdev, .slot = slot, .ret = 0,
750 };
751
752 pci_walk_bus(pdev->bus, vfio_pci_walk_wrapper, &walk);
753
754 return walk.ret;
755 }
756
757 static int msix_mmappable_cap(struct vfio_pci_device *vdev,
758 struct vfio_info_cap *caps)
759 {
760 struct vfio_info_cap_header header = {
761 .id = VFIO_REGION_INFO_CAP_MSIX_MAPPABLE,
762 .version = 1
763 };
764
765 return vfio_info_add_capability(caps, &header, sizeof(header));
766 }
767
768 int vfio_pci_register_dev_region(struct vfio_pci_device *vdev,
769 unsigned int type, unsigned int subtype,
770 const struct vfio_pci_regops *ops,
771 size_t size, u32 flags, void *data)
772 {
773 struct vfio_pci_region *region;
774
775 region = krealloc(vdev->region,
776 (vdev->num_regions + 1) * sizeof(*region),
777 GFP_KERNEL);
778 if (!region)
779 return -ENOMEM;
780
781 vdev->region = region;
782 vdev->region[vdev->num_regions].type = type;
783 vdev->region[vdev->num_regions].subtype = subtype;
784 vdev->region[vdev->num_regions].ops = ops;
785 vdev->region[vdev->num_regions].size = size;
786 vdev->region[vdev->num_regions].flags = flags;
787 vdev->region[vdev->num_regions].data = data;
788
789 vdev->num_regions++;
790
791 return 0;
792 }
793
794 struct vfio_devices {
795 struct vfio_device **devices;
796 int cur_index;
797 int max_index;
798 };
799
800 static long vfio_pci_ioctl(void *device_data,
801 unsigned int cmd, unsigned long arg)
802 {
803 struct vfio_pci_device *vdev = device_data;
804 unsigned long minsz;
805
806 if (cmd == VFIO_DEVICE_GET_INFO) {
807 struct vfio_device_info info;
808 struct vfio_info_cap caps = { .buf = NULL, .size = 0 };
809 unsigned long capsz;
810
811 minsz = offsetofend(struct vfio_device_info, num_irqs);
812
813 /* For backward compatibility, cannot require this */
814 capsz = offsetofend(struct vfio_iommu_type1_info, cap_offset);
815
816 if (copy_from_user(&info, (void __user *)arg, minsz))
817 return -EFAULT;
818
819 if (info.argsz < minsz)
820 return -EINVAL;
821
822 if (info.argsz >= capsz) {
823 minsz = capsz;
824 info.cap_offset = 0;
825 }
826
827 info.flags = VFIO_DEVICE_FLAGS_PCI;
828
829 if (vdev->reset_works)
830 info.flags |= VFIO_DEVICE_FLAGS_RESET;
831
832 info.num_regions = VFIO_PCI_NUM_REGIONS + vdev->num_regions;
833 info.num_irqs = VFIO_PCI_NUM_IRQS;
834
835 if (IS_ENABLED(CONFIG_VFIO_PCI_ZDEV)) {
836 int ret = vfio_pci_info_zdev_add_caps(vdev, &caps);
837
838 if (ret && ret != -ENODEV) {
839 pci_warn(vdev->pdev, "Failed to setup zPCI info capabilities\n");
840 return ret;
841 }
842 }
843
844 if (caps.size) {
845 info.flags |= VFIO_DEVICE_FLAGS_CAPS;
846 if (info.argsz < sizeof(info) + caps.size) {
847 info.argsz = sizeof(info) + caps.size;
848 } else {
849 vfio_info_cap_shift(&caps, sizeof(info));
850 if (copy_to_user((void __user *)arg +
851 sizeof(info), caps.buf,
852 caps.size)) {
853 kfree(caps.buf);
854 return -EFAULT;
855 }
856 info.cap_offset = sizeof(info);
857 }
858
859 kfree(caps.buf);
860 }
861
862 return copy_to_user((void __user *)arg, &info, minsz) ?
863 -EFAULT : 0;
864
865 } else if (cmd == VFIO_DEVICE_GET_REGION_INFO) {
866 struct pci_dev *pdev = vdev->pdev;
867 struct vfio_region_info info;
868 struct vfio_info_cap caps = { .buf = NULL, .size = 0 };
869 int i, ret;
870
871 minsz = offsetofend(struct vfio_region_info, offset);
872
873 if (copy_from_user(&info, (void __user *)arg, minsz))
874 return -EFAULT;
875
876 if (info.argsz < minsz)
877 return -EINVAL;
878
879 switch (info.index) {
880 case VFIO_PCI_CONFIG_REGION_INDEX:
881 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
882 info.size = pdev->cfg_size;
883 info.flags = VFIO_REGION_INFO_FLAG_READ |
884 VFIO_REGION_INFO_FLAG_WRITE;
885 break;
886 case VFIO_PCI_BAR0_REGION_INDEX ... VFIO_PCI_BAR5_REGION_INDEX:
887 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
888 info.size = pci_resource_len(pdev, info.index);
889 if (!info.size) {
890 info.flags = 0;
891 break;
892 }
893
894 info.flags = VFIO_REGION_INFO_FLAG_READ |
895 VFIO_REGION_INFO_FLAG_WRITE;
896 if (vdev->bar_mmap_supported[info.index]) {
897 info.flags |= VFIO_REGION_INFO_FLAG_MMAP;
898 if (info.index == vdev->msix_bar) {
899 ret = msix_mmappable_cap(vdev, &caps);
900 if (ret)
901 return ret;
902 }
903 }
904
905 break;
906 case VFIO_PCI_ROM_REGION_INDEX:
907 {
908 void __iomem *io;
909 size_t size;
910 u16 cmd;
911
912 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
913 info.flags = 0;
914
915 /* Report the BAR size, not the ROM size */
916 info.size = pci_resource_len(pdev, info.index);
917 if (!info.size) {
918 /* Shadow ROMs appear as PCI option ROMs */
919 if (pdev->resource[PCI_ROM_RESOURCE].flags &
920 IORESOURCE_ROM_SHADOW)
921 info.size = 0x20000;
922 else
923 break;
924 }
925
926 /*
927 * Is it really there? Enable memory decode for
928 * implicit access in pci_map_rom().
929 */
930 cmd = vfio_pci_memory_lock_and_enable(vdev);
931 io = pci_map_rom(pdev, &size);
932 if (io) {
933 info.flags = VFIO_REGION_INFO_FLAG_READ;
934 pci_unmap_rom(pdev, io);
935 } else {
936 info.size = 0;
937 }
938 vfio_pci_memory_unlock_and_restore(vdev, cmd);
939
940 break;
941 }
942 case VFIO_PCI_VGA_REGION_INDEX:
943 if (!vdev->has_vga)
944 return -EINVAL;
945
946 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
947 info.size = 0xc0000;
948 info.flags = VFIO_REGION_INFO_FLAG_READ |
949 VFIO_REGION_INFO_FLAG_WRITE;
950
951 break;
952 default:
953 {
954 struct vfio_region_info_cap_type cap_type = {
955 .header.id = VFIO_REGION_INFO_CAP_TYPE,
956 .header.version = 1 };
957
958 if (info.index >=
959 VFIO_PCI_NUM_REGIONS + vdev->num_regions)
960 return -EINVAL;
961 info.index = array_index_nospec(info.index,
962 VFIO_PCI_NUM_REGIONS +
963 vdev->num_regions);
964
965 i = info.index - VFIO_PCI_NUM_REGIONS;
966
967 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
968 info.size = vdev->region[i].size;
969 info.flags = vdev->region[i].flags;
970
971 cap_type.type = vdev->region[i].type;
972 cap_type.subtype = vdev->region[i].subtype;
973
974 ret = vfio_info_add_capability(&caps, &cap_type.header,
975 sizeof(cap_type));
976 if (ret)
977 return ret;
978
979 if (vdev->region[i].ops->add_capability) {
980 ret = vdev->region[i].ops->add_capability(vdev,
981 &vdev->region[i], &caps);
982 if (ret)
983 return ret;
984 }
985 }
986 }
987
988 if (caps.size) {
989 info.flags |= VFIO_REGION_INFO_FLAG_CAPS;
990 if (info.argsz < sizeof(info) + caps.size) {
991 info.argsz = sizeof(info) + caps.size;
992 info.cap_offset = 0;
993 } else {
994 vfio_info_cap_shift(&caps, sizeof(info));
995 if (copy_to_user((void __user *)arg +
996 sizeof(info), caps.buf,
997 caps.size)) {
998 kfree(caps.buf);
999 return -EFAULT;
1000 }
1001 info.cap_offset = sizeof(info);
1002 }
1003
1004 kfree(caps.buf);
1005 }
1006
1007 return copy_to_user((void __user *)arg, &info, minsz) ?
1008 -EFAULT : 0;
1009
1010 } else if (cmd == VFIO_DEVICE_GET_IRQ_INFO) {
1011 struct vfio_irq_info info;
1012
1013 minsz = offsetofend(struct vfio_irq_info, count);
1014
1015 if (copy_from_user(&info, (void __user *)arg, minsz))
1016 return -EFAULT;
1017
1018 if (info.argsz < minsz || info.index >= VFIO_PCI_NUM_IRQS)
1019 return -EINVAL;
1020
1021 switch (info.index) {
1022 case VFIO_PCI_INTX_IRQ_INDEX ... VFIO_PCI_MSIX_IRQ_INDEX:
1023 case VFIO_PCI_REQ_IRQ_INDEX:
1024 break;
1025 case VFIO_PCI_ERR_IRQ_INDEX:
1026 if (pci_is_pcie(vdev->pdev))
1027 break;
1028 fallthrough;
1029 default:
1030 return -EINVAL;
1031 }
1032
1033 info.flags = VFIO_IRQ_INFO_EVENTFD;
1034
1035 info.count = vfio_pci_get_irq_count(vdev, info.index);
1036
1037 if (info.index == VFIO_PCI_INTX_IRQ_INDEX)
1038 info.flags |= (VFIO_IRQ_INFO_MASKABLE |
1039 VFIO_IRQ_INFO_AUTOMASKED);
1040 else
1041 info.flags |= VFIO_IRQ_INFO_NORESIZE;
1042
1043 return copy_to_user((void __user *)arg, &info, minsz) ?
1044 -EFAULT : 0;
1045
1046 } else if (cmd == VFIO_DEVICE_SET_IRQS) {
1047 struct vfio_irq_set hdr;
1048 u8 *data = NULL;
1049 int max, ret = 0;
1050 size_t data_size = 0;
1051
1052 minsz = offsetofend(struct vfio_irq_set, count);
1053
1054 if (copy_from_user(&hdr, (void __user *)arg, minsz))
1055 return -EFAULT;
1056
1057 max = vfio_pci_get_irq_count(vdev, hdr.index);
1058
1059 ret = vfio_set_irqs_validate_and_prepare(&hdr, max,
1060 VFIO_PCI_NUM_IRQS, &data_size);
1061 if (ret)
1062 return ret;
1063
1064 if (data_size) {
1065 data = memdup_user((void __user *)(arg + minsz),
1066 data_size);
1067 if (IS_ERR(data))
1068 return PTR_ERR(data);
1069 }
1070
1071 mutex_lock(&vdev->igate);
1072
1073 ret = vfio_pci_set_irqs_ioctl(vdev, hdr.flags, hdr.index,
1074 hdr.start, hdr.count, data);
1075
1076 mutex_unlock(&vdev->igate);
1077 kfree(data);
1078
1079 return ret;
1080
1081 } else if (cmd == VFIO_DEVICE_RESET) {
1082 int ret;
1083
1084 if (!vdev->reset_works)
1085 return -EINVAL;
1086
1087 vfio_pci_zap_and_down_write_memory_lock(vdev);
1088 ret = pci_try_reset_function(vdev->pdev);
1089 up_write(&vdev->memory_lock);
1090
1091 return ret;
1092
1093 } else if (cmd == VFIO_DEVICE_GET_PCI_HOT_RESET_INFO) {
1094 struct vfio_pci_hot_reset_info hdr;
1095 struct vfio_pci_fill_info fill = { 0 };
1096 struct vfio_pci_dependent_device *devices = NULL;
1097 bool slot = false;
1098 int ret = 0;
1099
1100 minsz = offsetofend(struct vfio_pci_hot_reset_info, count);
1101
1102 if (copy_from_user(&hdr, (void __user *)arg, minsz))
1103 return -EFAULT;
1104
1105 if (hdr.argsz < minsz)
1106 return -EINVAL;
1107
1108 hdr.flags = 0;
1109
1110 /* Can we do a slot or bus reset or neither? */
1111 if (!pci_probe_reset_slot(vdev->pdev->slot))
1112 slot = true;
1113 else if (pci_probe_reset_bus(vdev->pdev->bus))
1114 return -ENODEV;
1115
1116 /* How many devices are affected? */
1117 ret = vfio_pci_for_each_slot_or_bus(vdev->pdev,
1118 vfio_pci_count_devs,
1119 &fill.max, slot);
1120 if (ret)
1121 return ret;
1122
1123 WARN_ON(!fill.max); /* Should always be at least one */
1124
1125 /*
1126 * If there's enough space, fill it now, otherwise return
1127 * -ENOSPC and the number of devices affected.
1128 */
1129 if (hdr.argsz < sizeof(hdr) + (fill.max * sizeof(*devices))) {
1130 ret = -ENOSPC;
1131 hdr.count = fill.max;
1132 goto reset_info_exit;
1133 }
1134
1135 devices = kcalloc(fill.max, sizeof(*devices), GFP_KERNEL);
1136 if (!devices)
1137 return -ENOMEM;
1138
1139 fill.devices = devices;
1140
1141 ret = vfio_pci_for_each_slot_or_bus(vdev->pdev,
1142 vfio_pci_fill_devs,
1143 &fill, slot);
1144
1145 /*
1146 * If a device was removed between counting and filling,
1147 * we may come up short of fill.max. If a device was
1148 * added, we'll have a return of -EAGAIN above.
1149 */
1150 if (!ret)
1151 hdr.count = fill.cur;
1152
1153 reset_info_exit:
1154 if (copy_to_user((void __user *)arg, &hdr, minsz))
1155 ret = -EFAULT;
1156
1157 if (!ret) {
1158 if (copy_to_user((void __user *)(arg + minsz), devices,
1159 hdr.count * sizeof(*devices)))
1160 ret = -EFAULT;
1161 }
1162
1163 kfree(devices);
1164 return ret;
1165
1166 } else if (cmd == VFIO_DEVICE_PCI_HOT_RESET) {
1167 struct vfio_pci_hot_reset hdr;
1168 int32_t *group_fds;
1169 struct vfio_pci_group_entry *groups;
1170 struct vfio_pci_group_info info;
1171 struct vfio_devices devs = { .cur_index = 0 };
1172 bool slot = false;
1173 int i, group_idx, mem_idx = 0, count = 0, ret = 0;
1174
1175 minsz = offsetofend(struct vfio_pci_hot_reset, count);
1176
1177 if (copy_from_user(&hdr, (void __user *)arg, minsz))
1178 return -EFAULT;
1179
1180 if (hdr.argsz < minsz || hdr.flags)
1181 return -EINVAL;
1182
1183 /* Can we do a slot or bus reset or neither? */
1184 if (!pci_probe_reset_slot(vdev->pdev->slot))
1185 slot = true;
1186 else if (pci_probe_reset_bus(vdev->pdev->bus))
1187 return -ENODEV;
1188
1189 /*
1190 * We can't let userspace give us an arbitrarily large
1191 * buffer to copy, so verify how many we think there
1192 * could be. Note groups can have multiple devices so
1193 * one group per device is the max.
1194 */
1195 ret = vfio_pci_for_each_slot_or_bus(vdev->pdev,
1196 vfio_pci_count_devs,
1197 &count, slot);
1198 if (ret)
1199 return ret;
1200
1201 /* Somewhere between 1 and count is OK */
1202 if (!hdr.count || hdr.count > count)
1203 return -EINVAL;
1204
1205 group_fds = kcalloc(hdr.count, sizeof(*group_fds), GFP_KERNEL);
1206 groups = kcalloc(hdr.count, sizeof(*groups), GFP_KERNEL);
1207 if (!group_fds || !groups) {
1208 kfree(group_fds);
1209 kfree(groups);
1210 return -ENOMEM;
1211 }
1212
1213 if (copy_from_user(group_fds, (void __user *)(arg + minsz),
1214 hdr.count * sizeof(*group_fds))) {
1215 kfree(group_fds);
1216 kfree(groups);
1217 return -EFAULT;
1218 }
1219
1220 /*
1221 * For each group_fd, get the group through the vfio external
1222 * user interface and store the group and iommu ID. This
1223 * ensures the group is held across the reset.
1224 */
1225 for (group_idx = 0; group_idx < hdr.count; group_idx++) {
1226 struct vfio_group *group;
1227 struct fd f = fdget(group_fds[group_idx]);
1228 if (!f.file) {
1229 ret = -EBADF;
1230 break;
1231 }
1232
1233 group = vfio_group_get_external_user(f.file);
1234 fdput(f);
1235 if (IS_ERR(group)) {
1236 ret = PTR_ERR(group);
1237 break;
1238 }
1239
1240 groups[group_idx].group = group;
1241 groups[group_idx].id =
1242 vfio_external_user_iommu_id(group);
1243 }
1244
1245 kfree(group_fds);
1246
1247 /* release reference to groups on error */
1248 if (ret)
1249 goto hot_reset_release;
1250
1251 info.count = hdr.count;
1252 info.groups = groups;
1253
1254 /*
1255 * Test whether all the affected devices are contained
1256 * by the set of groups provided by the user.
1257 */
1258 ret = vfio_pci_for_each_slot_or_bus(vdev->pdev,
1259 vfio_pci_validate_devs,
1260 &info, slot);
1261 if (ret)
1262 goto hot_reset_release;
1263
1264 devs.max_index = count;
1265 devs.devices = kcalloc(count, sizeof(struct vfio_device *),
1266 GFP_KERNEL);
1267 if (!devs.devices) {
1268 ret = -ENOMEM;
1269 goto hot_reset_release;
1270 }
1271
1272 /*
1273 * We need to get memory_lock for each device, but devices
1274 * can share mmap_lock, therefore we need to zap and hold
1275 * the vma_lock for each device, and only then get each
1276 * memory_lock.
1277 */
1278 ret = vfio_pci_for_each_slot_or_bus(vdev->pdev,
1279 vfio_pci_try_zap_and_vma_lock_cb,
1280 &devs, slot);
1281 if (ret)
1282 goto hot_reset_release;
1283
1284 for (; mem_idx < devs.cur_index; mem_idx++) {
1285 struct vfio_pci_device *tmp;
1286
1287 tmp = vfio_device_data(devs.devices[mem_idx]);
1288
1289 ret = down_write_trylock(&tmp->memory_lock);
1290 if (!ret) {
1291 ret = -EBUSY;
1292 goto hot_reset_release;
1293 }
1294 mutex_unlock(&tmp->vma_lock);
1295 }
1296
1297 /* User has access, do the reset */
1298 ret = pci_reset_bus(vdev->pdev);
1299
1300 hot_reset_release:
1301 for (i = 0; i < devs.cur_index; i++) {
1302 struct vfio_device *device;
1303 struct vfio_pci_device *tmp;
1304
1305 device = devs.devices[i];
1306 tmp = vfio_device_data(device);
1307
1308 if (i < mem_idx)
1309 up_write(&tmp->memory_lock);
1310 else
1311 mutex_unlock(&tmp->vma_lock);
1312 vfio_device_put(device);
1313 }
1314 kfree(devs.devices);
1315
1316 for (group_idx--; group_idx >= 0; group_idx--)
1317 vfio_group_put_external_user(groups[group_idx].group);
1318
1319 kfree(groups);
1320 return ret;
1321 } else if (cmd == VFIO_DEVICE_IOEVENTFD) {
1322 struct vfio_device_ioeventfd ioeventfd;
1323 int count;
1324
1325 minsz = offsetofend(struct vfio_device_ioeventfd, fd);
1326
1327 if (copy_from_user(&ioeventfd, (void __user *)arg, minsz))
1328 return -EFAULT;
1329
1330 if (ioeventfd.argsz < minsz)
1331 return -EINVAL;
1332
1333 if (ioeventfd.flags & ~VFIO_DEVICE_IOEVENTFD_SIZE_MASK)
1334 return -EINVAL;
1335
1336 count = ioeventfd.flags & VFIO_DEVICE_IOEVENTFD_SIZE_MASK;
1337
1338 if (hweight8(count) != 1 || ioeventfd.fd < -1)
1339 return -EINVAL;
1340
1341 return vfio_pci_ioeventfd(vdev, ioeventfd.offset,
1342 ioeventfd.data, count, ioeventfd.fd);
1343 } else if (cmd == VFIO_DEVICE_FEATURE) {
1344 struct vfio_device_feature feature;
1345 uuid_t uuid;
1346
1347 minsz = offsetofend(struct vfio_device_feature, flags);
1348
1349 if (copy_from_user(&feature, (void __user *)arg, minsz))
1350 return -EFAULT;
1351
1352 if (feature.argsz < minsz)
1353 return -EINVAL;
1354
1355 /* Check unknown flags */
1356 if (feature.flags & ~(VFIO_DEVICE_FEATURE_MASK |
1357 VFIO_DEVICE_FEATURE_SET |
1358 VFIO_DEVICE_FEATURE_GET |
1359 VFIO_DEVICE_FEATURE_PROBE))
1360 return -EINVAL;
1361
1362 /* GET & SET are mutually exclusive except with PROBE */
1363 if (!(feature.flags & VFIO_DEVICE_FEATURE_PROBE) &&
1364 (feature.flags & VFIO_DEVICE_FEATURE_SET) &&
1365 (feature.flags & VFIO_DEVICE_FEATURE_GET))
1366 return -EINVAL;
1367
1368 switch (feature.flags & VFIO_DEVICE_FEATURE_MASK) {
1369 case VFIO_DEVICE_FEATURE_PCI_VF_TOKEN:
1370 if (!vdev->vf_token)
1371 return -ENOTTY;
1372
1373 /*
1374 * We do not support GET of the VF Token UUID as this
1375 * could expose the token of the previous device user.
1376 */
1377 if (feature.flags & VFIO_DEVICE_FEATURE_GET)
1378 return -EINVAL;
1379
1380 if (feature.flags & VFIO_DEVICE_FEATURE_PROBE)
1381 return 0;
1382
1383 /* Don't SET unless told to do so */
1384 if (!(feature.flags & VFIO_DEVICE_FEATURE_SET))
1385 return -EINVAL;
1386
1387 if (feature.argsz < minsz + sizeof(uuid))
1388 return -EINVAL;
1389
1390 if (copy_from_user(&uuid, (void __user *)(arg + minsz),
1391 sizeof(uuid)))
1392 return -EFAULT;
1393
1394 mutex_lock(&vdev->vf_token->lock);
1395 uuid_copy(&vdev->vf_token->uuid, &uuid);
1396 mutex_unlock(&vdev->vf_token->lock);
1397
1398 return 0;
1399 default:
1400 return -ENOTTY;
1401 }
1402 }
1403
1404 return -ENOTTY;
1405 }
1406
1407 static ssize_t vfio_pci_rw(void *device_data, char __user *buf,
1408 size_t count, loff_t *ppos, bool iswrite)
1409 {
1410 unsigned int index = VFIO_PCI_OFFSET_TO_INDEX(*ppos);
1411 struct vfio_pci_device *vdev = device_data;
1412
1413 if (index >= VFIO_PCI_NUM_REGIONS + vdev->num_regions)
1414 return -EINVAL;
1415
1416 switch (index) {
1417 case VFIO_PCI_CONFIG_REGION_INDEX:
1418 return vfio_pci_config_rw(vdev, buf, count, ppos, iswrite);
1419
1420 case VFIO_PCI_ROM_REGION_INDEX:
1421 if (iswrite)
1422 return -EINVAL;
1423 return vfio_pci_bar_rw(vdev, buf, count, ppos, false);
1424
1425 case VFIO_PCI_BAR0_REGION_INDEX ... VFIO_PCI_BAR5_REGION_INDEX:
1426 return vfio_pci_bar_rw(vdev, buf, count, ppos, iswrite);
1427
1428 case VFIO_PCI_VGA_REGION_INDEX:
1429 return vfio_pci_vga_rw(vdev, buf, count, ppos, iswrite);
1430 default:
1431 index -= VFIO_PCI_NUM_REGIONS;
1432 return vdev->region[index].ops->rw(vdev, buf,
1433 count, ppos, iswrite);
1434 }
1435
1436 return -EINVAL;
1437 }
1438
1439 static ssize_t vfio_pci_read(void *device_data, char __user *buf,
1440 size_t count, loff_t *ppos)
1441 {
1442 if (!count)
1443 return 0;
1444
1445 return vfio_pci_rw(device_data, buf, count, ppos, false);
1446 }
1447
1448 static ssize_t vfio_pci_write(void *device_data, const char __user *buf,
1449 size_t count, loff_t *ppos)
1450 {
1451 if (!count)
1452 return 0;
1453
1454 return vfio_pci_rw(device_data, (char __user *)buf, count, ppos, true);
1455 }
1456
1457 /* Return 1 on zap and vma_lock acquired, 0 on contention (only with @try) */
1458 static int vfio_pci_zap_and_vma_lock(struct vfio_pci_device *vdev, bool try)
1459 {
1460 struct vfio_pci_mmap_vma *mmap_vma, *tmp;
1461
1462 /*
1463 * Lock ordering:
1464 * vma_lock is nested under mmap_lock for vm_ops callback paths.
1465 * The memory_lock semaphore is used by both code paths calling
1466 * into this function to zap vmas and the vm_ops.fault callback
1467 * to protect the memory enable state of the device.
1468 *
1469 * When zapping vmas we need to maintain the mmap_lock => vma_lock
1470 * ordering, which requires using vma_lock to walk vma_list to
1471 * acquire an mm, then dropping vma_lock to get the mmap_lock and
1472 * reacquiring vma_lock. This logic is derived from similar
1473 * requirements in uverbs_user_mmap_disassociate().
1474 *
1475 * mmap_lock must always be the top-level lock when it is taken.
1476 * Therefore we can only hold the memory_lock write lock when
1477 * vma_list is empty, as we'd need to take mmap_lock to clear
1478 * entries. vma_list can only be guaranteed empty when holding
1479 * vma_lock, thus memory_lock is nested under vma_lock.
1480 *
1481 * This enables the vm_ops.fault callback to acquire vma_lock,
1482 * followed by memory_lock read lock, while already holding
1483 * mmap_lock without risk of deadlock.
1484 */
1485 while (1) {
1486 struct mm_struct *mm = NULL;
1487
1488 if (try) {
1489 if (!mutex_trylock(&vdev->vma_lock))
1490 return 0;
1491 } else {
1492 mutex_lock(&vdev->vma_lock);
1493 }
1494 while (!list_empty(&vdev->vma_list)) {
1495 mmap_vma = list_first_entry(&vdev->vma_list,
1496 struct vfio_pci_mmap_vma,
1497 vma_next);
1498 mm = mmap_vma->vma->vm_mm;
1499 if (mmget_not_zero(mm))
1500 break;
1501
1502 list_del(&mmap_vma->vma_next);
1503 kfree(mmap_vma);
1504 mm = NULL;
1505 }
1506 if (!mm)
1507 return 1;
1508 mutex_unlock(&vdev->vma_lock);
1509
1510 if (try) {
1511 if (!mmap_read_trylock(mm)) {
1512 mmput(mm);
1513 return 0;
1514 }
1515 } else {
1516 mmap_read_lock(mm);
1517 }
1518 if (try) {
1519 if (!mutex_trylock(&vdev->vma_lock)) {
1520 mmap_read_unlock(mm);
1521 mmput(mm);
1522 return 0;
1523 }
1524 } else {
1525 mutex_lock(&vdev->vma_lock);
1526 }
1527 list_for_each_entry_safe(mmap_vma, tmp,
1528 &vdev->vma_list, vma_next) {
1529 struct vm_area_struct *vma = mmap_vma->vma;
1530
1531 if (vma->vm_mm != mm)
1532 continue;
1533
1534 list_del(&mmap_vma->vma_next);
1535 kfree(mmap_vma);
1536
1537 zap_vma_ptes(vma, vma->vm_start,
1538 vma->vm_end - vma->vm_start);
1539 }
1540 mutex_unlock(&vdev->vma_lock);
1541 mmap_read_unlock(mm);
1542 mmput(mm);
1543 }
1544 }
1545
1546 void vfio_pci_zap_and_down_write_memory_lock(struct vfio_pci_device *vdev)
1547 {
1548 vfio_pci_zap_and_vma_lock(vdev, false);
1549 down_write(&vdev->memory_lock);
1550 mutex_unlock(&vdev->vma_lock);
1551 }
1552
1553 u16 vfio_pci_memory_lock_and_enable(struct vfio_pci_device *vdev)
1554 {
1555 u16 cmd;
1556
1557 down_write(&vdev->memory_lock);
1558 pci_read_config_word(vdev->pdev, PCI_COMMAND, &cmd);
1559 if (!(cmd & PCI_COMMAND_MEMORY))
1560 pci_write_config_word(vdev->pdev, PCI_COMMAND,
1561 cmd | PCI_COMMAND_MEMORY);
1562
1563 return cmd;
1564 }
1565
1566 void vfio_pci_memory_unlock_and_restore(struct vfio_pci_device *vdev, u16 cmd)
1567 {
1568 pci_write_config_word(vdev->pdev, PCI_COMMAND, cmd);
1569 up_write(&vdev->memory_lock);
1570 }
1571
1572 /* Caller holds vma_lock */
1573 static int __vfio_pci_add_vma(struct vfio_pci_device *vdev,
1574 struct vm_area_struct *vma)
1575 {
1576 struct vfio_pci_mmap_vma *mmap_vma;
1577
1578 mmap_vma = kmalloc(sizeof(*mmap_vma), GFP_KERNEL);
1579 if (!mmap_vma)
1580 return -ENOMEM;
1581
1582 mmap_vma->vma = vma;
1583 list_add(&mmap_vma->vma_next, &vdev->vma_list);
1584
1585 return 0;
1586 }
1587
1588 /*
1589 * Zap mmaps on open so that we can fault them in on access and therefore
1590 * our vma_list only tracks mappings accessed since last zap.
1591 */
1592 static void vfio_pci_mmap_open(struct vm_area_struct *vma)
1593 {
1594 zap_vma_ptes(vma, vma->vm_start, vma->vm_end - vma->vm_start);
1595 }
1596
1597 static void vfio_pci_mmap_close(struct vm_area_struct *vma)
1598 {
1599 struct vfio_pci_device *vdev = vma->vm_private_data;
1600 struct vfio_pci_mmap_vma *mmap_vma;
1601
1602 mutex_lock(&vdev->vma_lock);
1603 list_for_each_entry(mmap_vma, &vdev->vma_list, vma_next) {
1604 if (mmap_vma->vma == vma) {
1605 list_del(&mmap_vma->vma_next);
1606 kfree(mmap_vma);
1607 break;
1608 }
1609 }
1610 mutex_unlock(&vdev->vma_lock);
1611 }
1612
1613 static vm_fault_t vfio_pci_mmap_fault(struct vm_fault *vmf)
1614 {
1615 struct vm_area_struct *vma = vmf->vma;
1616 struct vfio_pci_device *vdev = vma->vm_private_data;
1617 vm_fault_t ret = VM_FAULT_NOPAGE;
1618
1619 mutex_lock(&vdev->vma_lock);
1620 down_read(&vdev->memory_lock);
1621
1622 if (!__vfio_pci_memory_enabled(vdev)) {
1623 ret = VM_FAULT_SIGBUS;
1624 mutex_unlock(&vdev->vma_lock);
1625 goto up_out;
1626 }
1627
1628 if (__vfio_pci_add_vma(vdev, vma)) {
1629 ret = VM_FAULT_OOM;
1630 mutex_unlock(&vdev->vma_lock);
1631 goto up_out;
1632 }
1633
1634 mutex_unlock(&vdev->vma_lock);
1635
1636 if (io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
1637 vma->vm_end - vma->vm_start, vma->vm_page_prot))
1638 ret = VM_FAULT_SIGBUS;
1639
1640 up_out:
1641 up_read(&vdev->memory_lock);
1642 return ret;
1643 }
1644
1645 static const struct vm_operations_struct vfio_pci_mmap_ops = {
1646 .open = vfio_pci_mmap_open,
1647 .close = vfio_pci_mmap_close,
1648 .fault = vfio_pci_mmap_fault,
1649 };
1650
1651 static int vfio_pci_mmap(void *device_data, struct vm_area_struct *vma)
1652 {
1653 struct vfio_pci_device *vdev = device_data;
1654 struct pci_dev *pdev = vdev->pdev;
1655 unsigned int index;
1656 u64 phys_len, req_len, pgoff, req_start;
1657 int ret;
1658
1659 index = vma->vm_pgoff >> (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT);
1660
1661 if (vma->vm_end < vma->vm_start)
1662 return -EINVAL;
1663 if ((vma->vm_flags & VM_SHARED) == 0)
1664 return -EINVAL;
1665 if (index >= VFIO_PCI_NUM_REGIONS) {
1666 int regnum = index - VFIO_PCI_NUM_REGIONS;
1667 struct vfio_pci_region *region = vdev->region + regnum;
1668
1669 if (region && region->ops && region->ops->mmap &&
1670 (region->flags & VFIO_REGION_INFO_FLAG_MMAP))
1671 return region->ops->mmap(vdev, region, vma);
1672 return -EINVAL;
1673 }
1674 if (index >= VFIO_PCI_ROM_REGION_INDEX)
1675 return -EINVAL;
1676 if (!vdev->bar_mmap_supported[index])
1677 return -EINVAL;
1678
1679 phys_len = PAGE_ALIGN(pci_resource_len(pdev, index));
1680 req_len = vma->vm_end - vma->vm_start;
1681 pgoff = vma->vm_pgoff &
1682 ((1U << (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
1683 req_start = pgoff << PAGE_SHIFT;
1684
1685 if (req_start + req_len > phys_len)
1686 return -EINVAL;
1687
1688 /*
1689 * Even though we don't make use of the barmap for the mmap,
1690 * we need to request the region and the barmap tracks that.
1691 */
1692 if (!vdev->barmap[index]) {
1693 ret = pci_request_selected_regions(pdev,
1694 1 << index, "vfio-pci");
1695 if (ret)
1696 return ret;
1697
1698 vdev->barmap[index] = pci_iomap(pdev, index, 0);
1699 if (!vdev->barmap[index]) {
1700 pci_release_selected_regions(pdev, 1 << index);
1701 return -ENOMEM;
1702 }
1703 }
1704
1705 vma->vm_private_data = vdev;
1706 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
1707 vma->vm_pgoff = (pci_resource_start(pdev, index) >> PAGE_SHIFT) + pgoff;
1708
1709 /*
1710 * See remap_pfn_range(), called from vfio_pci_fault() but we can't
1711 * change vm_flags within the fault handler. Set them now.
1712 */
1713 vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
1714 vma->vm_ops = &vfio_pci_mmap_ops;
1715
1716 return 0;
1717 }
1718
1719 static void vfio_pci_request(void *device_data, unsigned int count)
1720 {
1721 struct vfio_pci_device *vdev = device_data;
1722 struct pci_dev *pdev = vdev->pdev;
1723
1724 mutex_lock(&vdev->igate);
1725
1726 if (vdev->req_trigger) {
1727 if (!(count % 10))
1728 pci_notice_ratelimited(pdev,
1729 "Relaying device request to user (#%u)\n",
1730 count);
1731 eventfd_signal(vdev->req_trigger, 1);
1732 } else if (count == 0) {
1733 pci_warn(pdev,
1734 "No device request channel registered, blocked until released by user\n");
1735 }
1736
1737 mutex_unlock(&vdev->igate);
1738 }
1739
1740 static int vfio_pci_validate_vf_token(struct vfio_pci_device *vdev,
1741 bool vf_token, uuid_t *uuid)
1742 {
1743 /*
1744 * There's always some degree of trust or collaboration between SR-IOV
1745 * PF and VFs, even if just that the PF hosts the SR-IOV capability and
1746 * can disrupt VFs with a reset, but often the PF has more explicit
1747 * access to deny service to the VF or access data passed through the
1748 * VF. We therefore require an opt-in via a shared VF token (UUID) to
1749 * represent this trust. This both prevents that a VF driver might
1750 * assume the PF driver is a trusted, in-kernel driver, and also that
1751 * a PF driver might be replaced with a rogue driver, unknown to in-use
1752 * VF drivers.
1753 *
1754 * Therefore when presented with a VF, if the PF is a vfio device and
1755 * it is bound to the vfio-pci driver, the user needs to provide a VF
1756 * token to access the device, in the form of appending a vf_token to
1757 * the device name, for example:
1758 *
1759 * "0000:04:10.0 vf_token=bd8d9d2b-5a5f-4f5a-a211-f591514ba1f3"
1760 *
1761 * When presented with a PF which has VFs in use, the user must also
1762 * provide the current VF token to prove collaboration with existing
1763 * VF users. If VFs are not in use, the VF token provided for the PF
1764 * device will act to set the VF token.
1765 *
1766 * If the VF token is provided but unused, an error is generated.
1767 */
1768 if (!vdev->pdev->is_virtfn && !vdev->vf_token && !vf_token)
1769 return 0; /* No VF token provided or required */
1770
1771 if (vdev->pdev->is_virtfn) {
1772 struct vfio_device *pf_dev;
1773 struct vfio_pci_device *pf_vdev = get_pf_vdev(vdev, &pf_dev);
1774 bool match;
1775
1776 if (!pf_vdev) {
1777 if (!vf_token)
1778 return 0; /* PF is not vfio-pci, no VF token */
1779
1780 pci_info_ratelimited(vdev->pdev,
1781 "VF token incorrectly provided, PF not bound to vfio-pci\n");
1782 return -EINVAL;
1783 }
1784
1785 if (!vf_token) {
1786 vfio_device_put(pf_dev);
1787 pci_info_ratelimited(vdev->pdev,
1788 "VF token required to access device\n");
1789 return -EACCES;
1790 }
1791
1792 mutex_lock(&pf_vdev->vf_token->lock);
1793 match = uuid_equal(uuid, &pf_vdev->vf_token->uuid);
1794 mutex_unlock(&pf_vdev->vf_token->lock);
1795
1796 vfio_device_put(pf_dev);
1797
1798 if (!match) {
1799 pci_info_ratelimited(vdev->pdev,
1800 "Incorrect VF token provided for device\n");
1801 return -EACCES;
1802 }
1803 } else if (vdev->vf_token) {
1804 mutex_lock(&vdev->vf_token->lock);
1805 if (vdev->vf_token->users) {
1806 if (!vf_token) {
1807 mutex_unlock(&vdev->vf_token->lock);
1808 pci_info_ratelimited(vdev->pdev,
1809 "VF token required to access device\n");
1810 return -EACCES;
1811 }
1812
1813 if (!uuid_equal(uuid, &vdev->vf_token->uuid)) {
1814 mutex_unlock(&vdev->vf_token->lock);
1815 pci_info_ratelimited(vdev->pdev,
1816 "Incorrect VF token provided for device\n");
1817 return -EACCES;
1818 }
1819 } else if (vf_token) {
1820 uuid_copy(&vdev->vf_token->uuid, uuid);
1821 }
1822
1823 mutex_unlock(&vdev->vf_token->lock);
1824 } else if (vf_token) {
1825 pci_info_ratelimited(vdev->pdev,
1826 "VF token incorrectly provided, not a PF or VF\n");
1827 return -EINVAL;
1828 }
1829
1830 return 0;
1831 }
1832
1833 #define VF_TOKEN_ARG "vf_token="
1834
1835 static int vfio_pci_match(void *device_data, char *buf)
1836 {
1837 struct vfio_pci_device *vdev = device_data;
1838 bool vf_token = false;
1839 uuid_t uuid;
1840 int ret;
1841
1842 if (strncmp(pci_name(vdev->pdev), buf, strlen(pci_name(vdev->pdev))))
1843 return 0; /* No match */
1844
1845 if (strlen(buf) > strlen(pci_name(vdev->pdev))) {
1846 buf += strlen(pci_name(vdev->pdev));
1847
1848 if (*buf != ' ')
1849 return 0; /* No match: non-whitespace after name */
1850
1851 while (*buf) {
1852 if (*buf == ' ') {
1853 buf++;
1854 continue;
1855 }
1856
1857 if (!vf_token && !strncmp(buf, VF_TOKEN_ARG,
1858 strlen(VF_TOKEN_ARG))) {
1859 buf += strlen(VF_TOKEN_ARG);
1860
1861 if (strlen(buf) < UUID_STRING_LEN)
1862 return -EINVAL;
1863
1864 ret = uuid_parse(buf, &uuid);
1865 if (ret)
1866 return ret;
1867
1868 vf_token = true;
1869 buf += UUID_STRING_LEN;
1870 } else {
1871 /* Unknown/duplicate option */
1872 return -EINVAL;
1873 }
1874 }
1875 }
1876
1877 ret = vfio_pci_validate_vf_token(vdev, vf_token, &uuid);
1878 if (ret)
1879 return ret;
1880
1881 return 1; /* Match */
1882 }
1883
1884 static const struct vfio_device_ops vfio_pci_ops = {
1885 .name = "vfio-pci",
1886 .open = vfio_pci_open,
1887 .release = vfio_pci_release,
1888 .ioctl = vfio_pci_ioctl,
1889 .read = vfio_pci_read,
1890 .write = vfio_pci_write,
1891 .mmap = vfio_pci_mmap,
1892 .request = vfio_pci_request,
1893 .match = vfio_pci_match,
1894 };
1895
1896 static int vfio_pci_reflck_attach(struct vfio_pci_device *vdev);
1897 static void vfio_pci_reflck_put(struct vfio_pci_reflck *reflck);
1898
1899 static int vfio_pci_bus_notifier(struct notifier_block *nb,
1900 unsigned long action, void *data)
1901 {
1902 struct vfio_pci_device *vdev = container_of(nb,
1903 struct vfio_pci_device, nb);
1904 struct device *dev = data;
1905 struct pci_dev *pdev = to_pci_dev(dev);
1906 struct pci_dev *physfn = pci_physfn(pdev);
1907
1908 if (action == BUS_NOTIFY_ADD_DEVICE &&
1909 pdev->is_virtfn && physfn == vdev->pdev) {
1910 pci_info(vdev->pdev, "Captured SR-IOV VF %s driver_override\n",
1911 pci_name(pdev));
1912 pdev->driver_override = kasprintf(GFP_KERNEL, "%s",
1913 vfio_pci_ops.name);
1914 } else if (action == BUS_NOTIFY_BOUND_DRIVER &&
1915 pdev->is_virtfn && physfn == vdev->pdev) {
1916 struct pci_driver *drv = pci_dev_driver(pdev);
1917
1918 if (drv && drv != &vfio_pci_driver)
1919 pci_warn(vdev->pdev,
1920 "VF %s bound to driver %s while PF bound to vfio-pci\n",
1921 pci_name(pdev), drv->name);
1922 }
1923
1924 return 0;
1925 }
1926
1927 static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
1928 {
1929 struct vfio_pci_device *vdev;
1930 struct iommu_group *group;
1931 int ret;
1932
1933 if (vfio_pci_is_denylisted(pdev))
1934 return -EINVAL;
1935
1936 if (pdev->hdr_type != PCI_HEADER_TYPE_NORMAL)
1937 return -EINVAL;
1938
1939 /*
1940 * Prevent binding to PFs with VFs enabled, the VFs might be in use
1941 * by the host or other users. We cannot capture the VFs if they
1942 * already exist, nor can we track VF users. Disabling SR-IOV here
1943 * would initiate removing the VFs, which would unbind the driver,
1944 * which is prone to blocking if that VF is also in use by vfio-pci.
1945 * Just reject these PFs and let the user sort it out.
1946 */
1947 if (pci_num_vf(pdev)) {
1948 pci_warn(pdev, "Cannot bind to PF with SR-IOV enabled\n");
1949 return -EBUSY;
1950 }
1951
1952 group = vfio_iommu_group_get(&pdev->dev);
1953 if (!group)
1954 return -EINVAL;
1955
1956 vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);
1957 if (!vdev) {
1958 ret = -ENOMEM;
1959 goto out_group_put;
1960 }
1961
1962 vdev->pdev = pdev;
1963 vdev->irq_type = VFIO_PCI_NUM_IRQS;
1964 mutex_init(&vdev->igate);
1965 spin_lock_init(&vdev->irqlock);
1966 mutex_init(&vdev->ioeventfds_lock);
1967 INIT_LIST_HEAD(&vdev->dummy_resources_list);
1968 INIT_LIST_HEAD(&vdev->ioeventfds_list);
1969 mutex_init(&vdev->vma_lock);
1970 INIT_LIST_HEAD(&vdev->vma_list);
1971 init_rwsem(&vdev->memory_lock);
1972
1973 ret = vfio_add_group_dev(&pdev->dev, &vfio_pci_ops, vdev);
1974 if (ret)
1975 goto out_free;
1976
1977 ret = vfio_pci_reflck_attach(vdev);
1978 if (ret)
1979 goto out_del_group_dev;
1980
1981 if (pdev->is_physfn) {
1982 vdev->vf_token = kzalloc(sizeof(*vdev->vf_token), GFP_KERNEL);
1983 if (!vdev->vf_token) {
1984 ret = -ENOMEM;
1985 goto out_reflck;
1986 }
1987
1988 mutex_init(&vdev->vf_token->lock);
1989 uuid_gen(&vdev->vf_token->uuid);
1990
1991 vdev->nb.notifier_call = vfio_pci_bus_notifier;
1992 ret = bus_register_notifier(&pci_bus_type, &vdev->nb);
1993 if (ret)
1994 goto out_vf_token;
1995 }
1996
1997 if (vfio_pci_is_vga(pdev)) {
1998 vga_client_register(pdev, vdev, NULL, vfio_pci_set_vga_decode);
1999 vga_set_legacy_decoding(pdev,
2000 vfio_pci_set_vga_decode(vdev, false));
2001 }
2002
2003 vfio_pci_probe_power_state(vdev);
2004
2005 if (!disable_idle_d3) {
2006 /*
2007 * pci-core sets the device power state to an unknown value at
2008 * bootup and after being removed from a driver. The only
2009 * transition it allows from this unknown state is to D0, which
2010 * typically happens when a driver calls pci_enable_device().
2011 * We're not ready to enable the device yet, but we do want to
2012 * be able to get to D3. Therefore first do a D0 transition
2013 * before going to D3.
2014 */
2015 vfio_pci_set_power_state(vdev, PCI_D0);
2016 vfio_pci_set_power_state(vdev, PCI_D3hot);
2017 }
2018
2019 return ret;
2020
2021 out_vf_token:
2022 kfree(vdev->vf_token);
2023 out_reflck:
2024 vfio_pci_reflck_put(vdev->reflck);
2025 out_del_group_dev:
2026 vfio_del_group_dev(&pdev->dev);
2027 out_free:
2028 kfree(vdev);
2029 out_group_put:
2030 vfio_iommu_group_put(group, &pdev->dev);
2031 return ret;
2032 }
2033
2034 static void vfio_pci_remove(struct pci_dev *pdev)
2035 {
2036 struct vfio_pci_device *vdev;
2037
2038 pci_disable_sriov(pdev);
2039
2040 vdev = vfio_del_group_dev(&pdev->dev);
2041 if (!vdev)
2042 return;
2043
2044 if (vdev->vf_token) {
2045 WARN_ON(vdev->vf_token->users);
2046 mutex_destroy(&vdev->vf_token->lock);
2047 kfree(vdev->vf_token);
2048 }
2049
2050 if (vdev->nb.notifier_call)
2051 bus_unregister_notifier(&pci_bus_type, &vdev->nb);
2052
2053 vfio_pci_reflck_put(vdev->reflck);
2054
2055 vfio_iommu_group_put(pdev->dev.iommu_group, &pdev->dev);
2056 kfree(vdev->region);
2057 mutex_destroy(&vdev->ioeventfds_lock);
2058
2059 if (!disable_idle_d3)
2060 vfio_pci_set_power_state(vdev, PCI_D0);
2061
2062 kfree(vdev->pm_save);
2063 kfree(vdev);
2064
2065 if (vfio_pci_is_vga(pdev)) {
2066 vga_client_register(pdev, NULL, NULL, NULL);
2067 vga_set_legacy_decoding(pdev,
2068 VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM |
2069 VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM);
2070 }
2071 }
2072
2073 static pci_ers_result_t vfio_pci_aer_err_detected(struct pci_dev *pdev,
2074 pci_channel_state_t state)
2075 {
2076 struct vfio_pci_device *vdev;
2077 struct vfio_device *device;
2078
2079 device = vfio_device_get_from_dev(&pdev->dev);
2080 if (device == NULL)
2081 return PCI_ERS_RESULT_DISCONNECT;
2082
2083 vdev = vfio_device_data(device);
2084 if (vdev == NULL) {
2085 vfio_device_put(device);
2086 return PCI_ERS_RESULT_DISCONNECT;
2087 }
2088
2089 mutex_lock(&vdev->igate);
2090
2091 if (vdev->err_trigger)
2092 eventfd_signal(vdev->err_trigger, 1);
2093
2094 mutex_unlock(&vdev->igate);
2095
2096 vfio_device_put(device);
2097
2098 return PCI_ERS_RESULT_CAN_RECOVER;
2099 }
2100
2101 static int vfio_pci_sriov_configure(struct pci_dev *pdev, int nr_virtfn)
2102 {
2103 struct vfio_pci_device *vdev;
2104 struct vfio_device *device;
2105 int ret = 0;
2106
2107 might_sleep();
2108
2109 if (!enable_sriov)
2110 return -ENOENT;
2111
2112 device = vfio_device_get_from_dev(&pdev->dev);
2113 if (!device)
2114 return -ENODEV;
2115
2116 vdev = vfio_device_data(device);
2117 if (!vdev) {
2118 vfio_device_put(device);
2119 return -ENODEV;
2120 }
2121
2122 if (nr_virtfn == 0)
2123 pci_disable_sriov(pdev);
2124 else
2125 ret = pci_enable_sriov(pdev, nr_virtfn);
2126
2127 vfio_device_put(device);
2128
2129 return ret < 0 ? ret : nr_virtfn;
2130 }
2131
2132 static const struct pci_error_handlers vfio_err_handlers = {
2133 .error_detected = vfio_pci_aer_err_detected,
2134 };
2135
2136 static struct pci_driver vfio_pci_driver = {
2137 .name = "vfio-pci",
2138 .id_table = NULL, /* only dynamic ids */
2139 .probe = vfio_pci_probe,
2140 .remove = vfio_pci_remove,
2141 .sriov_configure = vfio_pci_sriov_configure,
2142 .err_handler = &vfio_err_handlers,
2143 };
2144
2145 static DEFINE_MUTEX(reflck_lock);
2146
2147 static struct vfio_pci_reflck *vfio_pci_reflck_alloc(void)
2148 {
2149 struct vfio_pci_reflck *reflck;
2150
2151 reflck = kzalloc(sizeof(*reflck), GFP_KERNEL);
2152 if (!reflck)
2153 return ERR_PTR(-ENOMEM);
2154
2155 kref_init(&reflck->kref);
2156 mutex_init(&reflck->lock);
2157
2158 return reflck;
2159 }
2160
2161 static void vfio_pci_reflck_get(struct vfio_pci_reflck *reflck)
2162 {
2163 kref_get(&reflck->kref);
2164 }
2165
2166 static int vfio_pci_reflck_find(struct pci_dev *pdev, void *data)
2167 {
2168 struct vfio_pci_reflck **preflck = data;
2169 struct vfio_device *device;
2170 struct vfio_pci_device *vdev;
2171
2172 device = vfio_device_get_from_dev(&pdev->dev);
2173 if (!device)
2174 return 0;
2175
2176 if (pci_dev_driver(pdev) != &vfio_pci_driver) {
2177 vfio_device_put(device);
2178 return 0;
2179 }
2180
2181 vdev = vfio_device_data(device);
2182
2183 if (vdev->reflck) {
2184 vfio_pci_reflck_get(vdev->reflck);
2185 *preflck = vdev->reflck;
2186 vfio_device_put(device);
2187 return 1;
2188 }
2189
2190 vfio_device_put(device);
2191 return 0;
2192 }
2193
2194 static int vfio_pci_reflck_attach(struct vfio_pci_device *vdev)
2195 {
2196 bool slot = !pci_probe_reset_slot(vdev->pdev->slot);
2197
2198 mutex_lock(&reflck_lock);
2199
2200 if (pci_is_root_bus(vdev->pdev->bus) ||
2201 vfio_pci_for_each_slot_or_bus(vdev->pdev, vfio_pci_reflck_find,
2202 &vdev->reflck, slot) <= 0)
2203 vdev->reflck = vfio_pci_reflck_alloc();
2204
2205 mutex_unlock(&reflck_lock);
2206
2207 return PTR_ERR_OR_ZERO(vdev->reflck);
2208 }
2209
2210 static void vfio_pci_reflck_release(struct kref *kref)
2211 {
2212 struct vfio_pci_reflck *reflck = container_of(kref,
2213 struct vfio_pci_reflck,
2214 kref);
2215
2216 kfree(reflck);
2217 mutex_unlock(&reflck_lock);
2218 }
2219
2220 static void vfio_pci_reflck_put(struct vfio_pci_reflck *reflck)
2221 {
2222 kref_put_mutex(&reflck->kref, vfio_pci_reflck_release, &reflck_lock);
2223 }
2224
2225 static int vfio_pci_get_unused_devs(struct pci_dev *pdev, void *data)
2226 {
2227 struct vfio_devices *devs = data;
2228 struct vfio_device *device;
2229 struct vfio_pci_device *vdev;
2230
2231 if (devs->cur_index == devs->max_index)
2232 return -ENOSPC;
2233
2234 device = vfio_device_get_from_dev(&pdev->dev);
2235 if (!device)
2236 return -EINVAL;
2237
2238 if (pci_dev_driver(pdev) != &vfio_pci_driver) {
2239 vfio_device_put(device);
2240 return -EBUSY;
2241 }
2242
2243 vdev = vfio_device_data(device);
2244
2245 /* Fault if the device is not unused */
2246 if (vdev->refcnt) {
2247 vfio_device_put(device);
2248 return -EBUSY;
2249 }
2250
2251 devs->devices[devs->cur_index++] = device;
2252 return 0;
2253 }
2254
2255 static int vfio_pci_try_zap_and_vma_lock_cb(struct pci_dev *pdev, void *data)
2256 {
2257 struct vfio_devices *devs = data;
2258 struct vfio_device *device;
2259 struct vfio_pci_device *vdev;
2260
2261 if (devs->cur_index == devs->max_index)
2262 return -ENOSPC;
2263
2264 device = vfio_device_get_from_dev(&pdev->dev);
2265 if (!device)
2266 return -EINVAL;
2267
2268 if (pci_dev_driver(pdev) != &vfio_pci_driver) {
2269 vfio_device_put(device);
2270 return -EBUSY;
2271 }
2272
2273 vdev = vfio_device_data(device);
2274
2275 /*
2276 * Locking multiple devices is prone to deadlock, runaway and
2277 * unwind if we hit contention.
2278 */
2279 if (!vfio_pci_zap_and_vma_lock(vdev, true)) {
2280 vfio_device_put(device);
2281 return -EBUSY;
2282 }
2283
2284 devs->devices[devs->cur_index++] = device;
2285 return 0;
2286 }
2287
2288 /*
2289 * If a bus or slot reset is available for the provided device and:
2290 * - All of the devices affected by that bus or slot reset are unused
2291 * (!refcnt)
2292 * - At least one of the affected devices is marked dirty via
2293 * needs_reset (such as by lack of FLR support)
2294 * Then attempt to perform that bus or slot reset. Callers are required
2295 * to hold vdev->reflck->lock, protecting the bus/slot reset group from
2296 * concurrent opens. A vfio_device reference is acquired for each device
2297 * to prevent unbinds during the reset operation.
2298 *
2299 * NB: vfio-core considers a group to be viable even if some devices are
2300 * bound to drivers like pci-stub or pcieport. Here we require all devices
2301 * to be bound to vfio_pci since that's the only way we can be sure they
2302 * stay put.
2303 */
2304 static void vfio_pci_try_bus_reset(struct vfio_pci_device *vdev)
2305 {
2306 struct vfio_devices devs = { .cur_index = 0 };
2307 int i = 0, ret = -EINVAL;
2308 bool slot = false;
2309 struct vfio_pci_device *tmp;
2310
2311 if (!pci_probe_reset_slot(vdev->pdev->slot))
2312 slot = true;
2313 else if (pci_probe_reset_bus(vdev->pdev->bus))
2314 return;
2315
2316 if (vfio_pci_for_each_slot_or_bus(vdev->pdev, vfio_pci_count_devs,
2317 &i, slot) || !i)
2318 return;
2319
2320 devs.max_index = i;
2321 devs.devices = kcalloc(i, sizeof(struct vfio_device *), GFP_KERNEL);
2322 if (!devs.devices)
2323 return;
2324
2325 if (vfio_pci_for_each_slot_or_bus(vdev->pdev,
2326 vfio_pci_get_unused_devs,
2327 &devs, slot))
2328 goto put_devs;
2329
2330 /* Does at least one need a reset? */
2331 for (i = 0; i < devs.cur_index; i++) {
2332 tmp = vfio_device_data(devs.devices[i]);
2333 if (tmp->needs_reset) {
2334 ret = pci_reset_bus(vdev->pdev);
2335 break;
2336 }
2337 }
2338
2339 put_devs:
2340 for (i = 0; i < devs.cur_index; i++) {
2341 tmp = vfio_device_data(devs.devices[i]);
2342
2343 /*
2344 * If reset was successful, affected devices no longer need
2345 * a reset and we should return all the collateral devices
2346 * to low power. If not successful, we either didn't reset
2347 * the bus or timed out waiting for it, so let's not touch
2348 * the power state.
2349 */
2350 if (!ret) {
2351 tmp->needs_reset = false;
2352
2353 if (tmp != vdev && !disable_idle_d3)
2354 vfio_pci_set_power_state(tmp, PCI_D3hot);
2355 }
2356
2357 vfio_device_put(devs.devices[i]);
2358 }
2359
2360 kfree(devs.devices);
2361 }
2362
2363 static void __exit vfio_pci_cleanup(void)
2364 {
2365 pci_unregister_driver(&vfio_pci_driver);
2366 vfio_pci_uninit_perm_bits();
2367 }
2368
2369 static void __init vfio_pci_fill_ids(void)
2370 {
2371 char *p, *id;
2372 int rc;
2373
2374 /* no ids passed actually */
2375 if (ids[0] == '\0')
2376 return;
2377
2378 /* add ids specified in the module parameter */
2379 p = ids;
2380 while ((id = strsep(&p, ","))) {
2381 unsigned int vendor, device, subvendor = PCI_ANY_ID,
2382 subdevice = PCI_ANY_ID, class = 0, class_mask = 0;
2383 int fields;
2384
2385 if (!strlen(id))
2386 continue;
2387
2388 fields = sscanf(id, "%x:%x:%x:%x:%x:%x",
2389 &vendor, &device, &subvendor, &subdevice,
2390 &class, &class_mask);
2391
2392 if (fields < 2) {
2393 pr_warn("invalid id string \"%s\"\n", id);
2394 continue;
2395 }
2396
2397 rc = pci_add_dynid(&vfio_pci_driver, vendor, device,
2398 subvendor, subdevice, class, class_mask, 0);
2399 if (rc)
2400 pr_warn("failed to add dynamic id [%04x:%04x[%04x:%04x]] class %#08x/%08x (%d)\n",
2401 vendor, device, subvendor, subdevice,
2402 class, class_mask, rc);
2403 else
2404 pr_info("add [%04x:%04x[%04x:%04x]] class %#08x/%08x\n",
2405 vendor, device, subvendor, subdevice,
2406 class, class_mask);
2407 }
2408 }
2409
2410 static int __init vfio_pci_init(void)
2411 {
2412 int ret;
2413
2414 /* Allocate shared config space permision data used by all devices */
2415 ret = vfio_pci_init_perm_bits();
2416 if (ret)
2417 return ret;
2418
2419 /* Register and scan for devices */
2420 ret = pci_register_driver(&vfio_pci_driver);
2421 if (ret)
2422 goto out_driver;
2423
2424 vfio_pci_fill_ids();
2425
2426 if (disable_denylist)
2427 pr_warn("device denylist disabled.\n");
2428
2429 return 0;
2430
2431 out_driver:
2432 vfio_pci_uninit_perm_bits();
2433 return ret;
2434 }
2435
2436 module_init(vfio_pci_init);
2437 module_exit(vfio_pci_cleanup);
2438
2439 MODULE_VERSION(DRIVER_VERSION);
2440 MODULE_LICENSE("GPL v2");
2441 MODULE_AUTHOR(DRIVER_AUTHOR);
2442 MODULE_DESCRIPTION(DRIVER_DESC);
Linux with added FPC-III support