2 * Copyright (C) 2012 Red Hat, Inc. All rights reserved.
3 * Author: Alex Williamson <alex.williamson@redhat.com>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
9 * Derived from original vfio:
10 * Copyright 2010 Cisco Systems, Inc. All rights reserved.
11 * Author: Tom Lyon, pugs@cisco.com
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/pm_runtime.h>
24 #include <linux/slab.h>
25 #include <linux/types.h>
26 #include <linux/uaccess.h>
27 #include <linux/vfio.h>
29 #include "vfio_pci_private.h"
31 #define DRIVER_VERSION "0.2"
32 #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
33 #define DRIVER_DESC "VFIO PCI - User Level meta-driver"
35 static bool nointxmask;
36 module_param_named(nointxmask, nointxmask, bool, S_IRUGO | S_IWUSR);
37 MODULE_PARM_DESC(nointxmask,
38 "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.");
40 static DEFINE_MUTEX(driver_lock);
42 static void vfio_pci_try_bus_reset(struct vfio_pci_device *vdev);
44 static int vfio_pci_enable(struct vfio_pci_device *vdev)
46 struct pci_dev *pdev = vdev->pdev;
51 /* Don't allow our initial saved state to include busmaster */
52 pci_clear_master(pdev);
54 ret = pci_enable_device(pdev);
58 vdev->reset_works = (pci_reset_function(pdev) == 0);
60 vdev->pci_saved_state = pci_store_saved_state(pdev);
61 if (!vdev->pci_saved_state)
62 pr_debug("%s: Couldn't store %s saved state\n",
63 __func__, dev_name(&pdev->dev));
65 ret = vfio_config_init(vdev);
67 kfree(vdev->pci_saved_state);
68 vdev->pci_saved_state = NULL;
69 pci_disable_device(pdev);
73 if (likely(!nointxmask))
74 vdev->pci_2_3 = pci_intx_mask_supported(pdev);
76 pci_read_config_word(pdev, PCI_COMMAND, &cmd);
77 if (vdev->pci_2_3 && (cmd & PCI_COMMAND_INTX_DISABLE)) {
78 cmd &= ~PCI_COMMAND_INTX_DISABLE;
79 pci_write_config_word(pdev, PCI_COMMAND, cmd);
82 msix_pos = pdev->msix_cap;
87 pci_read_config_word(pdev, msix_pos + PCI_MSIX_FLAGS, &flags);
88 pci_read_config_dword(pdev, msix_pos + PCI_MSIX_TABLE, &table);
90 vdev->msix_bar = table & PCI_MSIX_TABLE_BIR;
91 vdev->msix_offset = table & PCI_MSIX_TABLE_OFFSET;
92 vdev->msix_size = ((flags & PCI_MSIX_FLAGS_QSIZE) + 1) * 16;
94 vdev->msix_bar = 0xFF;
96 #ifdef CONFIG_VFIO_PCI_VGA
97 if ((pdev->class >> 8) == PCI_CLASS_DISPLAY_VGA)
104 static void vfio_pci_disable(struct vfio_pci_device *vdev)
106 struct pci_dev *pdev = vdev->pdev;
109 /* Stop the device from further DMA */
110 pci_clear_master(pdev);
112 vfio_pci_set_irqs_ioctl(vdev, VFIO_IRQ_SET_DATA_NONE |
113 VFIO_IRQ_SET_ACTION_TRIGGER,
114 vdev->irq_type, 0, 0, NULL);
116 vdev->virq_disabled = false;
118 vfio_config_free(vdev);
120 for (bar = PCI_STD_RESOURCES; bar <= PCI_STD_RESOURCE_END; bar++) {
121 if (!vdev->barmap[bar])
123 pci_iounmap(pdev, vdev->barmap[bar]);
124 pci_release_selected_regions(pdev, 1 << bar);
125 vdev->barmap[bar] = NULL;
128 vdev->needs_reset = true;
131 * If we have saved state, restore it. If we can reset the device,
132 * even better. Resetting with current state seems better than
133 * nothing, but saving and restoring current state without reset
136 if (pci_load_and_free_saved_state(pdev, &vdev->pci_saved_state)) {
137 pr_info("%s: Couldn't reload %s saved state\n",
138 __func__, dev_name(&pdev->dev));
140 if (!vdev->reset_works)
143 pci_save_state(pdev);
147 * Disable INTx and MSI, presumably to avoid spurious interrupts
148 * during reset. Stolen from pci_reset_function()
150 pci_write_config_word(pdev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE);
153 * Try to reset the device. The success of this is dependent on
154 * being able to lock the device, which is not always possible.
156 if (vdev->reset_works) {
157 int ret = pci_try_reset_function(pdev);
159 pr_warn("%s: Failed to reset device %s (%d)\n",
160 __func__, dev_name(&pdev->dev), ret);
162 vdev->needs_reset = false;
165 pci_restore_state(pdev);
167 pci_disable_device(pdev);
169 vfio_pci_try_bus_reset(vdev);
172 static void vfio_pci_release(void *device_data)
174 struct vfio_pci_device *vdev = device_data;
176 mutex_lock(&driver_lock);
178 if (!(--vdev->refcnt)) {
179 vfio_spapr_pci_eeh_release(vdev->pdev);
180 vfio_pci_disable(vdev);
183 mutex_unlock(&driver_lock);
185 module_put(THIS_MODULE);
188 static int vfio_pci_open(void *device_data)
190 struct vfio_pci_device *vdev = device_data;
193 if (!try_module_get(THIS_MODULE))
196 mutex_lock(&driver_lock);
199 ret = vfio_pci_enable(vdev);
203 vfio_spapr_pci_eeh_open(vdev->pdev);
207 mutex_unlock(&driver_lock);
209 module_put(THIS_MODULE);
213 static int vfio_pci_get_irq_count(struct vfio_pci_device *vdev, int irq_type)
215 if (irq_type == VFIO_PCI_INTX_IRQ_INDEX) {
217 pci_read_config_byte(vdev->pdev, PCI_INTERRUPT_PIN, &pin);
218 if (IS_ENABLED(CONFIG_VFIO_PCI_INTX) && pin)
221 } else if (irq_type == VFIO_PCI_MSI_IRQ_INDEX) {
225 pos = vdev->pdev->msi_cap;
227 pci_read_config_word(vdev->pdev,
228 pos + PCI_MSI_FLAGS, &flags);
229 return 1 << ((flags & PCI_MSI_FLAGS_QMASK) >> 1);
231 } else if (irq_type == VFIO_PCI_MSIX_IRQ_INDEX) {
235 pos = vdev->pdev->msix_cap;
237 pci_read_config_word(vdev->pdev,
238 pos + PCI_MSIX_FLAGS, &flags);
240 return (flags & PCI_MSIX_FLAGS_QSIZE) + 1;
242 } else if (irq_type == VFIO_PCI_ERR_IRQ_INDEX)
243 if (pci_is_pcie(vdev->pdev))
249 static int vfio_pci_count_devs(struct pci_dev *pdev, void *data)
255 struct vfio_pci_fill_info {
258 struct vfio_pci_dependent_device *devices;
261 static int vfio_pci_fill_devs(struct pci_dev *pdev, void *data)
263 struct vfio_pci_fill_info *fill = data;
264 struct iommu_group *iommu_group;
266 if (fill->cur == fill->max)
267 return -EAGAIN; /* Something changed, try again */
269 iommu_group = iommu_group_get(&pdev->dev);
271 return -EPERM; /* Cannot reset non-isolated devices */
273 fill->devices[fill->cur].group_id = iommu_group_id(iommu_group);
274 fill->devices[fill->cur].segment = pci_domain_nr(pdev->bus);
275 fill->devices[fill->cur].bus = pdev->bus->number;
276 fill->devices[fill->cur].devfn = pdev->devfn;
278 iommu_group_put(iommu_group);
282 struct vfio_pci_group_entry {
283 struct vfio_group *group;
287 struct vfio_pci_group_info {
289 struct vfio_pci_group_entry *groups;
292 static int vfio_pci_validate_devs(struct pci_dev *pdev, void *data)
294 struct vfio_pci_group_info *info = data;
295 struct iommu_group *group;
298 group = iommu_group_get(&pdev->dev);
302 id = iommu_group_id(group);
304 for (i = 0; i < info->count; i++)
305 if (info->groups[i].id == id)
308 iommu_group_put(group);
310 return (i == info->count) ? -EINVAL : 0;
313 static bool vfio_pci_dev_below_slot(struct pci_dev *pdev, struct pci_slot *slot)
315 for (; pdev; pdev = pdev->bus->self)
316 if (pdev->bus == slot->bus)
317 return (pdev->slot == slot);
321 struct vfio_pci_walk_info {
322 int (*fn)(struct pci_dev *, void *data);
324 struct pci_dev *pdev;
329 static int vfio_pci_walk_wrapper(struct pci_dev *pdev, void *data)
331 struct vfio_pci_walk_info *walk = data;
333 if (!walk->slot || vfio_pci_dev_below_slot(pdev, walk->pdev->slot))
334 walk->ret = walk->fn(pdev, walk->data);
339 static int vfio_pci_for_each_slot_or_bus(struct pci_dev *pdev,
340 int (*fn)(struct pci_dev *,
341 void *data), void *data,
344 struct vfio_pci_walk_info walk = {
345 .fn = fn, .data = data, .pdev = pdev, .slot = slot, .ret = 0,
348 pci_walk_bus(pdev->bus, vfio_pci_walk_wrapper, &walk);
353 static long vfio_pci_ioctl(void *device_data,
354 unsigned int cmd, unsigned long arg)
356 struct vfio_pci_device *vdev = device_data;
359 if (cmd == VFIO_DEVICE_GET_INFO) {
360 struct vfio_device_info info;
362 minsz = offsetofend(struct vfio_device_info, num_irqs);
364 if (copy_from_user(&info, (void __user *)arg, minsz))
367 if (info.argsz < minsz)
370 info.flags = VFIO_DEVICE_FLAGS_PCI;
372 if (vdev->reset_works)
373 info.flags |= VFIO_DEVICE_FLAGS_RESET;
375 info.num_regions = VFIO_PCI_NUM_REGIONS;
376 info.num_irqs = VFIO_PCI_NUM_IRQS;
378 return copy_to_user((void __user *)arg, &info, minsz);
380 } else if (cmd == VFIO_DEVICE_GET_REGION_INFO) {
381 struct pci_dev *pdev = vdev->pdev;
382 struct vfio_region_info info;
384 minsz = offsetofend(struct vfio_region_info, offset);
386 if (copy_from_user(&info, (void __user *)arg, minsz))
389 if (info.argsz < minsz)
392 switch (info.index) {
393 case VFIO_PCI_CONFIG_REGION_INDEX:
394 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
395 info.size = pdev->cfg_size;
396 info.flags = VFIO_REGION_INFO_FLAG_READ |
397 VFIO_REGION_INFO_FLAG_WRITE;
399 case VFIO_PCI_BAR0_REGION_INDEX ... VFIO_PCI_BAR5_REGION_INDEX:
400 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
401 info.size = pci_resource_len(pdev, info.index);
407 info.flags = VFIO_REGION_INFO_FLAG_READ |
408 VFIO_REGION_INFO_FLAG_WRITE;
409 if (IS_ENABLED(CONFIG_VFIO_PCI_MMAP) &&
410 pci_resource_flags(pdev, info.index) &
411 IORESOURCE_MEM && info.size >= PAGE_SIZE)
412 info.flags |= VFIO_REGION_INFO_FLAG_MMAP;
414 case VFIO_PCI_ROM_REGION_INDEX:
419 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
422 /* Report the BAR size, not the ROM size */
423 info.size = pci_resource_len(pdev, info.index);
427 /* Is it really there? */
428 io = pci_map_rom(pdev, &size);
433 pci_unmap_rom(pdev, io);
435 info.flags = VFIO_REGION_INFO_FLAG_READ;
438 case VFIO_PCI_VGA_REGION_INDEX:
442 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
444 info.flags = VFIO_REGION_INFO_FLAG_READ |
445 VFIO_REGION_INFO_FLAG_WRITE;
452 return copy_to_user((void __user *)arg, &info, minsz);
454 } else if (cmd == VFIO_DEVICE_GET_IRQ_INFO) {
455 struct vfio_irq_info info;
457 minsz = offsetofend(struct vfio_irq_info, count);
459 if (copy_from_user(&info, (void __user *)arg, minsz))
462 if (info.argsz < minsz || info.index >= VFIO_PCI_NUM_IRQS)
465 switch (info.index) {
466 case VFIO_PCI_INTX_IRQ_INDEX ... VFIO_PCI_MSIX_IRQ_INDEX:
468 case VFIO_PCI_ERR_IRQ_INDEX:
469 if (pci_is_pcie(vdev->pdev))
471 /* pass thru to return error */
476 info.flags = VFIO_IRQ_INFO_EVENTFD;
478 info.count = vfio_pci_get_irq_count(vdev, info.index);
480 if (info.index == VFIO_PCI_INTX_IRQ_INDEX)
481 info.flags |= (VFIO_IRQ_INFO_MASKABLE |
482 VFIO_IRQ_INFO_AUTOMASKED);
484 info.flags |= VFIO_IRQ_INFO_NORESIZE;
486 return copy_to_user((void __user *)arg, &info, minsz);
488 } else if (cmd == VFIO_DEVICE_SET_IRQS) {
489 struct vfio_irq_set hdr;
493 minsz = offsetofend(struct vfio_irq_set, count);
495 if (copy_from_user(&hdr, (void __user *)arg, minsz))
498 if (hdr.argsz < minsz || hdr.index >= VFIO_PCI_NUM_IRQS ||
499 hdr.flags & ~(VFIO_IRQ_SET_DATA_TYPE_MASK |
500 VFIO_IRQ_SET_ACTION_TYPE_MASK))
503 if (!(hdr.flags & VFIO_IRQ_SET_DATA_NONE)) {
505 int max = vfio_pci_get_irq_count(vdev, hdr.index);
507 if (hdr.flags & VFIO_IRQ_SET_DATA_BOOL)
508 size = sizeof(uint8_t);
509 else if (hdr.flags & VFIO_IRQ_SET_DATA_EVENTFD)
510 size = sizeof(int32_t);
514 if (hdr.argsz - minsz < hdr.count * size ||
515 hdr.start >= max || hdr.start + hdr.count > max)
518 data = memdup_user((void __user *)(arg + minsz),
521 return PTR_ERR(data);
524 mutex_lock(&vdev->igate);
526 ret = vfio_pci_set_irqs_ioctl(vdev, hdr.flags, hdr.index,
527 hdr.start, hdr.count, data);
529 mutex_unlock(&vdev->igate);
534 } else if (cmd == VFIO_DEVICE_RESET) {
535 return vdev->reset_works ?
536 pci_try_reset_function(vdev->pdev) : -EINVAL;
538 } else if (cmd == VFIO_DEVICE_GET_PCI_HOT_RESET_INFO) {
539 struct vfio_pci_hot_reset_info hdr;
540 struct vfio_pci_fill_info fill = { 0 };
541 struct vfio_pci_dependent_device *devices = NULL;
545 minsz = offsetofend(struct vfio_pci_hot_reset_info, count);
547 if (copy_from_user(&hdr, (void __user *)arg, minsz))
550 if (hdr.argsz < minsz)
555 /* Can we do a slot or bus reset or neither? */
556 if (!pci_probe_reset_slot(vdev->pdev->slot))
558 else if (pci_probe_reset_bus(vdev->pdev->bus))
561 /* How many devices are affected? */
562 ret = vfio_pci_for_each_slot_or_bus(vdev->pdev,
568 WARN_ON(!fill.max); /* Should always be at least one */
571 * If there's enough space, fill it now, otherwise return
572 * -ENOSPC and the number of devices affected.
574 if (hdr.argsz < sizeof(hdr) + (fill.max * sizeof(*devices))) {
576 hdr.count = fill.max;
577 goto reset_info_exit;
580 devices = kcalloc(fill.max, sizeof(*devices), GFP_KERNEL);
584 fill.devices = devices;
586 ret = vfio_pci_for_each_slot_or_bus(vdev->pdev,
591 * If a device was removed between counting and filling,
592 * we may come up short of fill.max. If a device was
593 * added, we'll have a return of -EAGAIN above.
596 hdr.count = fill.cur;
599 if (copy_to_user((void __user *)arg, &hdr, minsz))
603 if (copy_to_user((void __user *)(arg + minsz), devices,
604 hdr.count * sizeof(*devices)))
611 } else if (cmd == VFIO_DEVICE_PCI_HOT_RESET) {
612 struct vfio_pci_hot_reset hdr;
614 struct vfio_pci_group_entry *groups;
615 struct vfio_pci_group_info info;
617 int i, count = 0, ret = 0;
619 minsz = offsetofend(struct vfio_pci_hot_reset, count);
621 if (copy_from_user(&hdr, (void __user *)arg, minsz))
624 if (hdr.argsz < minsz || hdr.flags)
627 /* Can we do a slot or bus reset or neither? */
628 if (!pci_probe_reset_slot(vdev->pdev->slot))
630 else if (pci_probe_reset_bus(vdev->pdev->bus))
634 * We can't let userspace give us an arbitrarily large
635 * buffer to copy, so verify how many we think there
636 * could be. Note groups can have multiple devices so
637 * one group per device is the max.
639 ret = vfio_pci_for_each_slot_or_bus(vdev->pdev,
645 /* Somewhere between 1 and count is OK */
646 if (!hdr.count || hdr.count > count)
649 group_fds = kcalloc(hdr.count, sizeof(*group_fds), GFP_KERNEL);
650 groups = kcalloc(hdr.count, sizeof(*groups), GFP_KERNEL);
651 if (!group_fds || !groups) {
657 if (copy_from_user(group_fds, (void __user *)(arg + minsz),
658 hdr.count * sizeof(*group_fds))) {
665 * For each group_fd, get the group through the vfio external
666 * user interface and store the group and iommu ID. This
667 * ensures the group is held across the reset.
669 for (i = 0; i < hdr.count; i++) {
670 struct vfio_group *group;
671 struct fd f = fdget(group_fds[i]);
677 group = vfio_group_get_external_user(f.file);
680 ret = PTR_ERR(group);
684 groups[i].group = group;
685 groups[i].id = vfio_external_user_iommu_id(group);
690 /* release reference to groups on error */
692 goto hot_reset_release;
694 info.count = hdr.count;
695 info.groups = groups;
698 * Test whether all the affected devices are contained
699 * by the set of groups provided by the user.
701 ret = vfio_pci_for_each_slot_or_bus(vdev->pdev,
702 vfio_pci_validate_devs,
705 /* User has access, do the reset */
706 ret = slot ? pci_try_reset_slot(vdev->pdev->slot) :
707 pci_try_reset_bus(vdev->pdev->bus);
710 for (i--; i >= 0; i--)
711 vfio_group_put_external_user(groups[i].group);
720 static ssize_t vfio_pci_rw(void *device_data, char __user *buf,
721 size_t count, loff_t *ppos, bool iswrite)
723 unsigned int index = VFIO_PCI_OFFSET_TO_INDEX(*ppos);
724 struct vfio_pci_device *vdev = device_data;
726 if (index >= VFIO_PCI_NUM_REGIONS)
730 case VFIO_PCI_CONFIG_REGION_INDEX:
731 return vfio_pci_config_rw(vdev, buf, count, ppos, iswrite);
733 case VFIO_PCI_ROM_REGION_INDEX:
736 return vfio_pci_bar_rw(vdev, buf, count, ppos, false);
738 case VFIO_PCI_BAR0_REGION_INDEX ... VFIO_PCI_BAR5_REGION_INDEX:
739 return vfio_pci_bar_rw(vdev, buf, count, ppos, iswrite);
741 case VFIO_PCI_VGA_REGION_INDEX:
742 return vfio_pci_vga_rw(vdev, buf, count, ppos, iswrite);
748 static ssize_t vfio_pci_read(void *device_data, char __user *buf,
749 size_t count, loff_t *ppos)
754 return vfio_pci_rw(device_data, buf, count, ppos, false);
757 static ssize_t vfio_pci_write(void *device_data, const char __user *buf,
758 size_t count, loff_t *ppos)
763 return vfio_pci_rw(device_data, (char __user *)buf, count, ppos, true);
766 static int vfio_pci_mmap(void *device_data, struct vm_area_struct *vma)
768 struct vfio_pci_device *vdev = device_data;
769 struct pci_dev *pdev = vdev->pdev;
771 u64 phys_len, req_len, pgoff, req_start;
774 index = vma->vm_pgoff >> (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT);
776 if (vma->vm_end < vma->vm_start)
778 if ((vma->vm_flags & VM_SHARED) == 0)
780 if (index >= VFIO_PCI_ROM_REGION_INDEX)
782 if (!(pci_resource_flags(pdev, index) & IORESOURCE_MEM))
785 phys_len = pci_resource_len(pdev, index);
786 req_len = vma->vm_end - vma->vm_start;
787 pgoff = vma->vm_pgoff &
788 ((1U << (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
789 req_start = pgoff << PAGE_SHIFT;
791 if (phys_len < PAGE_SIZE || req_start + req_len > phys_len)
794 if (index == vdev->msix_bar) {
796 * Disallow mmaps overlapping the MSI-X table; users don't
797 * get to touch this directly. We could find somewhere
798 * else to map the overlap, but page granularity is only
799 * a recommendation, not a requirement, so the user needs
800 * to know which bits are real. Requiring them to mmap
801 * around the table makes that clear.
804 /* If neither entirely above nor below, then it overlaps */
805 if (!(req_start >= vdev->msix_offset + vdev->msix_size ||
806 req_start + req_len <= vdev->msix_offset))
811 * Even though we don't make use of the barmap for the mmap,
812 * we need to request the region and the barmap tracks that.
814 if (!vdev->barmap[index]) {
815 ret = pci_request_selected_regions(pdev,
816 1 << index, "vfio-pci");
820 vdev->barmap[index] = pci_iomap(pdev, index, 0);
823 vma->vm_private_data = vdev;
824 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
825 vma->vm_pgoff = (pci_resource_start(pdev, index) >> PAGE_SHIFT) + pgoff;
827 return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
828 req_len, vma->vm_page_prot);
831 static const struct vfio_device_ops vfio_pci_ops = {
833 .open = vfio_pci_open,
834 .release = vfio_pci_release,
835 .ioctl = vfio_pci_ioctl,
836 .read = vfio_pci_read,
837 .write = vfio_pci_write,
838 .mmap = vfio_pci_mmap,
841 static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
844 struct vfio_pci_device *vdev;
845 struct iommu_group *group;
848 pci_read_config_byte(pdev, PCI_HEADER_TYPE, &type);
849 if ((type & PCI_HEADER_TYPE) != PCI_HEADER_TYPE_NORMAL)
852 group = iommu_group_get(&pdev->dev);
856 vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);
858 iommu_group_put(group);
863 vdev->irq_type = VFIO_PCI_NUM_IRQS;
864 mutex_init(&vdev->igate);
865 spin_lock_init(&vdev->irqlock);
867 ret = vfio_add_group_dev(&pdev->dev, &vfio_pci_ops, vdev);
869 iommu_group_put(group);
876 static void vfio_pci_remove(struct pci_dev *pdev)
878 struct vfio_pci_device *vdev;
880 vdev = vfio_del_group_dev(&pdev->dev);
882 iommu_group_put(pdev->dev.iommu_group);
887 static pci_ers_result_t vfio_pci_aer_err_detected(struct pci_dev *pdev,
888 pci_channel_state_t state)
890 struct vfio_pci_device *vdev;
891 struct vfio_device *device;
893 device = vfio_device_get_from_dev(&pdev->dev);
895 return PCI_ERS_RESULT_DISCONNECT;
897 vdev = vfio_device_data(device);
899 vfio_device_put(device);
900 return PCI_ERS_RESULT_DISCONNECT;
903 mutex_lock(&vdev->igate);
905 if (vdev->err_trigger)
906 eventfd_signal(vdev->err_trigger, 1);
908 mutex_unlock(&vdev->igate);
910 vfio_device_put(device);
912 return PCI_ERS_RESULT_CAN_RECOVER;
915 static struct pci_error_handlers vfio_err_handlers = {
916 .error_detected = vfio_pci_aer_err_detected,
919 static struct pci_driver vfio_pci_driver = {
921 .id_table = NULL, /* only dynamic ids */
922 .probe = vfio_pci_probe,
923 .remove = vfio_pci_remove,
924 .err_handler = &vfio_err_handlers,
927 struct vfio_devices {
928 struct vfio_device **devices;
933 static int vfio_pci_get_devs(struct pci_dev *pdev, void *data)
935 struct vfio_devices *devs = data;
936 struct pci_driver *pci_drv = ACCESS_ONCE(pdev->driver);
938 if (pci_drv != &vfio_pci_driver)
941 if (devs->cur_index == devs->max_index)
944 devs->devices[devs->cur_index] = vfio_device_get_from_dev(&pdev->dev);
945 if (!devs->devices[devs->cur_index])
953 * Attempt to do a bus/slot reset if there are devices affected by a reset for
954 * this device that are needs_reset and all of the affected devices are unused
955 * (!refcnt). Callers are required to hold driver_lock when calling this to
956 * prevent device opens and concurrent bus reset attempts. We prevent device
957 * unbinds by acquiring and holding a reference to the vfio_device.
959 * NB: vfio-core considers a group to be viable even if some devices are
960 * bound to drivers like pci-stub or pcieport. Here we require all devices
961 * to be bound to vfio_pci since that's the only way we can be sure they
964 static void vfio_pci_try_bus_reset(struct vfio_pci_device *vdev)
966 struct vfio_devices devs = { .cur_index = 0 };
967 int i = 0, ret = -EINVAL;
968 bool needs_reset = false, slot = false;
969 struct vfio_pci_device *tmp;
971 if (!pci_probe_reset_slot(vdev->pdev->slot))
973 else if (pci_probe_reset_bus(vdev->pdev->bus))
976 if (vfio_pci_for_each_slot_or_bus(vdev->pdev, vfio_pci_count_devs,
981 devs.devices = kcalloc(i, sizeof(struct vfio_device *), GFP_KERNEL);
985 if (vfio_pci_for_each_slot_or_bus(vdev->pdev,
986 vfio_pci_get_devs, &devs, slot))
989 for (i = 0; i < devs.cur_index; i++) {
990 tmp = vfio_device_data(devs.devices[i]);
991 if (tmp->needs_reset)
998 ret = slot ? pci_try_reset_slot(vdev->pdev->slot) :
999 pci_try_reset_bus(vdev->pdev->bus);
1002 for (i = 0; i < devs.cur_index; i++) {
1004 tmp = vfio_device_data(devs.devices[i]);
1005 tmp->needs_reset = false;
1007 vfio_device_put(devs.devices[i]);
1010 kfree(devs.devices);
1013 static void __exit vfio_pci_cleanup(void)
1015 pci_unregister_driver(&vfio_pci_driver);
1016 vfio_pci_virqfd_exit();
1017 vfio_pci_uninit_perm_bits();
1020 static int __init vfio_pci_init(void)
1024 /* Allocate shared config space permision data used by all devices */
1025 ret = vfio_pci_init_perm_bits();
1029 /* Start the virqfd cleanup handler */
1030 ret = vfio_pci_virqfd_init();
1034 /* Register and scan for devices */
1035 ret = pci_register_driver(&vfio_pci_driver);
1042 vfio_pci_virqfd_exit();
1044 vfio_pci_uninit_perm_bits();
1048 module_init(vfio_pci_init);
1049 module_exit(vfio_pci_cleanup);
1051 MODULE_VERSION(DRIVER_VERSION);
1052 MODULE_LICENSE("GPL v2");
1053 MODULE_AUTHOR(DRIVER_AUTHOR);
1054 MODULE_DESCRIPTION(DRIVER_DESC);