| /* |
| * Copyright (C) 2012 Red Hat, Inc. All rights reserved. |
| * Author: Alex Williamson <alex.williamson@redhat.com> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| * |
| * Derived from original vfio: |
| * Copyright 2010 Cisco Systems, Inc. All rights reserved. |
| * Author: Tom Lyon, pugs@cisco.com |
| */ |
| |
| #include <linux/device.h> |
| #include <linux/eventfd.h> |
| #include <linux/interrupt.h> |
| #include <linux/iommu.h> |
| #include <linux/module.h> |
| #include <linux/mutex.h> |
| #include <linux/notifier.h> |
| #include <linux/pci.h> |
| #include <linux/pm_runtime.h> |
| #include <linux/slab.h> |
| #include <linux/types.h> |
| #include <linux/uaccess.h> |
| #include <linux/vfio.h> |
| |
| #include "vfio_pci_private.h" |
| |
| #define DRIVER_VERSION "0.2" |
| #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>" |
| #define DRIVER_DESC "VFIO PCI - User Level meta-driver" |
| |
| static bool nointxmask; |
| module_param_named(nointxmask, nointxmask, bool, S_IRUGO | S_IWUSR); |
| MODULE_PARM_DESC(nointxmask, |
| "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."); |
| |
| static int vfio_pci_enable(struct vfio_pci_device *vdev) |
| { |
| struct pci_dev *pdev = vdev->pdev; |
| int ret; |
| u16 cmd; |
| u8 msix_pos; |
| |
| ret = pci_enable_device(pdev); |
| if (ret) |
| return ret; |
| |
| vdev->reset_works = (pci_reset_function(pdev) == 0); |
| pci_save_state(pdev); |
| vdev->pci_saved_state = pci_store_saved_state(pdev); |
| if (!vdev->pci_saved_state) |
| pr_debug("%s: Couldn't store %s saved state\n", |
| __func__, dev_name(&pdev->dev)); |
| |
| ret = vfio_config_init(vdev); |
| if (ret) { |
| pci_load_and_free_saved_state(pdev, &vdev->pci_saved_state); |
| pci_disable_device(pdev); |
| return ret; |
| } |
| |
| if (likely(!nointxmask)) |
| vdev->pci_2_3 = pci_intx_mask_supported(pdev); |
| |
| pci_read_config_word(pdev, PCI_COMMAND, &cmd); |
| if (vdev->pci_2_3 && (cmd & PCI_COMMAND_INTX_DISABLE)) { |
| cmd &= ~PCI_COMMAND_INTX_DISABLE; |
| pci_write_config_word(pdev, PCI_COMMAND, cmd); |
| } |
| |
| msix_pos = pci_find_capability(pdev, PCI_CAP_ID_MSIX); |
| if (msix_pos) { |
| u16 flags; |
| u32 table; |
| |
| pci_read_config_word(pdev, msix_pos + PCI_MSIX_FLAGS, &flags); |
| pci_read_config_dword(pdev, msix_pos + PCI_MSIX_TABLE, &table); |
| |
| vdev->msix_bar = table & PCI_MSIX_TABLE_BIR; |
| vdev->msix_offset = table & PCI_MSIX_TABLE_OFFSET; |
| vdev->msix_size = ((flags & PCI_MSIX_FLAGS_QSIZE) + 1) * 16; |
| } else |
| vdev->msix_bar = 0xFF; |
| |
| #ifdef CONFIG_VFIO_PCI_VGA |
| if ((pdev->class >> 8) == PCI_CLASS_DISPLAY_VGA) |
| vdev->has_vga = true; |
| #endif |
| |
| return 0; |
| } |
| |
| static void vfio_pci_disable(struct vfio_pci_device *vdev) |
| { |
| struct pci_dev *pdev = vdev->pdev; |
| int bar; |
| |
| pci_disable_device(pdev); |
| |
| vfio_pci_set_irqs_ioctl(vdev, VFIO_IRQ_SET_DATA_NONE | |
| VFIO_IRQ_SET_ACTION_TRIGGER, |
| vdev->irq_type, 0, 0, NULL); |
| |
| vdev->virq_disabled = false; |
| |
| vfio_config_free(vdev); |
| |
| for (bar = PCI_STD_RESOURCES; bar <= PCI_STD_RESOURCE_END; bar++) { |
| if (!vdev->barmap[bar]) |
| continue; |
| pci_iounmap(pdev, vdev->barmap[bar]); |
| pci_release_selected_regions(pdev, 1 << bar); |
| vdev->barmap[bar] = NULL; |
| } |
| |
| /* |
| * If we have saved state, restore it. If we can reset the device, |
| * even better. Resetting with current state seems better than |
| * nothing, but saving and restoring current state without reset |
| * is just busy work. |
| */ |
| if (pci_load_and_free_saved_state(pdev, &vdev->pci_saved_state)) { |
| pr_info("%s: Couldn't reload %s saved state\n", |
| __func__, dev_name(&pdev->dev)); |
| |
| if (!vdev->reset_works) |
| return; |
| |
| pci_save_state(pdev); |
| } |
| |
| /* |
| * Disable INTx and MSI, presumably to avoid spurious interrupts |
| * during reset. Stolen from pci_reset_function() |
| */ |
| pci_write_config_word(pdev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE); |
| |
| if (vdev->reset_works) |
| __pci_reset_function(pdev); |
| |
| pci_restore_state(pdev); |
| } |
| |
| static void vfio_pci_release(void *device_data) |
| { |
| struct vfio_pci_device *vdev = device_data; |
| |
| if (atomic_dec_and_test(&vdev->refcnt)) |
| vfio_pci_disable(vdev); |
| |
| module_put(THIS_MODULE); |
| } |
| |
| static int vfio_pci_open(void *device_data) |
| { |
| struct vfio_pci_device *vdev = device_data; |
| |
| if (!try_module_get(THIS_MODULE)) |
| return -ENODEV; |
| |
| if (atomic_inc_return(&vdev->refcnt) == 1) { |
| int ret = vfio_pci_enable(vdev); |
| if (ret) { |
| module_put(THIS_MODULE); |
| return ret; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static int vfio_pci_get_irq_count(struct vfio_pci_device *vdev, int irq_type) |
| { |
| if (irq_type == VFIO_PCI_INTX_IRQ_INDEX) { |
| u8 pin; |
| pci_read_config_byte(vdev->pdev, PCI_INTERRUPT_PIN, &pin); |
| if (pin) |
| return 1; |
| |
| } else if (irq_type == VFIO_PCI_MSI_IRQ_INDEX) { |
| u8 pos; |
| u16 flags; |
| |
| pos = pci_find_capability(vdev->pdev, PCI_CAP_ID_MSI); |
| if (pos) { |
| pci_read_config_word(vdev->pdev, |
| pos + PCI_MSI_FLAGS, &flags); |
| |
| return 1 << (flags & PCI_MSI_FLAGS_QMASK); |
| } |
| } else if (irq_type == VFIO_PCI_MSIX_IRQ_INDEX) { |
| u8 pos; |
| u16 flags; |
| |
| pos = pci_find_capability(vdev->pdev, PCI_CAP_ID_MSIX); |
| if (pos) { |
| pci_read_config_word(vdev->pdev, |
| pos + PCI_MSIX_FLAGS, &flags); |
| |
| return (flags & PCI_MSIX_FLAGS_QSIZE) + 1; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static long vfio_pci_ioctl(void *device_data, |
| unsigned int cmd, unsigned long arg) |
| { |
| struct vfio_pci_device *vdev = device_data; |
| unsigned long minsz; |
| |
| if (cmd == VFIO_DEVICE_GET_INFO) { |
| struct vfio_device_info info; |
| |
| minsz = offsetofend(struct vfio_device_info, num_irqs); |
| |
| if (copy_from_user(&info, (void __user *)arg, minsz)) |
| return -EFAULT; |
| |
| if (info.argsz < minsz) |
| return -EINVAL; |
| |
| info.flags = VFIO_DEVICE_FLAGS_PCI; |
| |
| if (vdev->reset_works) |
| info.flags |= VFIO_DEVICE_FLAGS_RESET; |
| |
| info.num_regions = VFIO_PCI_NUM_REGIONS; |
| info.num_irqs = VFIO_PCI_NUM_IRQS; |
| |
| return copy_to_user((void __user *)arg, &info, minsz); |
| |
| } else if (cmd == VFIO_DEVICE_GET_REGION_INFO) { |
| struct pci_dev *pdev = vdev->pdev; |
| struct vfio_region_info info; |
| |
| minsz = offsetofend(struct vfio_region_info, offset); |
| |
| if (copy_from_user(&info, (void __user *)arg, minsz)) |
| return -EFAULT; |
| |
| if (info.argsz < minsz) |
| return -EINVAL; |
| |
| switch (info.index) { |
| case VFIO_PCI_CONFIG_REGION_INDEX: |
| info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index); |
| info.size = pdev->cfg_size; |
| info.flags = VFIO_REGION_INFO_FLAG_READ | |
| VFIO_REGION_INFO_FLAG_WRITE; |
| break; |
| case VFIO_PCI_BAR0_REGION_INDEX ... VFIO_PCI_BAR5_REGION_INDEX: |
| info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index); |
| info.size = pci_resource_len(pdev, info.index); |
| if (!info.size) { |
| info.flags = 0; |
| break; |
| } |
| |
| info.flags = VFIO_REGION_INFO_FLAG_READ | |
| VFIO_REGION_INFO_FLAG_WRITE; |
| if (pci_resource_flags(pdev, info.index) & |
| IORESOURCE_MEM && info.size >= PAGE_SIZE) |
| info.flags |= VFIO_REGION_INFO_FLAG_MMAP; |
| break; |
| case VFIO_PCI_ROM_REGION_INDEX: |
| { |
| void __iomem *io; |
| size_t size; |
| |
| info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index); |
| info.flags = 0; |
| |
| /* Report the BAR size, not the ROM size */ |
| info.size = pci_resource_len(pdev, info.index); |
| if (!info.size) |
| break; |
| |
| /* Is it really there? */ |
| io = pci_map_rom(pdev, &size); |
| if (!io || !size) { |
| info.size = 0; |
| break; |
| } |
| pci_unmap_rom(pdev, io); |
| |
| info.flags = VFIO_REGION_INFO_FLAG_READ; |
| break; |
| } |
| case VFIO_PCI_VGA_REGION_INDEX: |
| if (!vdev->has_vga) |
| return -EINVAL; |
| |
| info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index); |
| info.size = 0xc0000; |
| info.flags = VFIO_REGION_INFO_FLAG_READ | |
| VFIO_REGION_INFO_FLAG_WRITE; |
| |
| break; |
| default: |
| return -EINVAL; |
| } |
| |
| return copy_to_user((void __user *)arg, &info, minsz); |
| |
| } else if (cmd == VFIO_DEVICE_GET_IRQ_INFO) { |
| struct vfio_irq_info info; |
| |
| minsz = offsetofend(struct vfio_irq_info, count); |
| |
| if (copy_from_user(&info, (void __user *)arg, minsz)) |
| return -EFAULT; |
| |
| if (info.argsz < minsz || info.index >= VFIO_PCI_NUM_IRQS) |
| return -EINVAL; |
| |
| info.flags = VFIO_IRQ_INFO_EVENTFD; |
| |
| info.count = vfio_pci_get_irq_count(vdev, info.index); |
| |
| if (info.index == VFIO_PCI_INTX_IRQ_INDEX) |
| info.flags |= (VFIO_IRQ_INFO_MASKABLE | |
| VFIO_IRQ_INFO_AUTOMASKED); |
| else |
| info.flags |= VFIO_IRQ_INFO_NORESIZE; |
| |
| return copy_to_user((void __user *)arg, &info, minsz); |
| |
| } else if (cmd == VFIO_DEVICE_SET_IRQS) { |
| struct vfio_irq_set hdr; |
| u8 *data = NULL; |
| int ret = 0; |
| |
| minsz = offsetofend(struct vfio_irq_set, count); |
| |
| if (copy_from_user(&hdr, (void __user *)arg, minsz)) |
| return -EFAULT; |
| |
| if (hdr.argsz < minsz || hdr.index >= VFIO_PCI_NUM_IRQS || |
| hdr.flags & ~(VFIO_IRQ_SET_DATA_TYPE_MASK | |
| VFIO_IRQ_SET_ACTION_TYPE_MASK)) |
| return -EINVAL; |
| |
| if (!(hdr.flags & VFIO_IRQ_SET_DATA_NONE)) { |
| size_t size; |
| |
| if (hdr.flags & VFIO_IRQ_SET_DATA_BOOL) |
| size = sizeof(uint8_t); |
| else if (hdr.flags & VFIO_IRQ_SET_DATA_EVENTFD) |
| size = sizeof(int32_t); |
| else |
| return -EINVAL; |
| |
| if (hdr.argsz - minsz < hdr.count * size || |
| hdr.count > vfio_pci_get_irq_count(vdev, hdr.index)) |
| return -EINVAL; |
| |
| data = memdup_user((void __user *)(arg + minsz), |
| hdr.count * size); |
| if (IS_ERR(data)) |
| return PTR_ERR(data); |
| } |
| |
| mutex_lock(&vdev->igate); |
| |
| ret = vfio_pci_set_irqs_ioctl(vdev, hdr.flags, hdr.index, |
| hdr.start, hdr.count, data); |
| |
| mutex_unlock(&vdev->igate); |
| kfree(data); |
| |
| return ret; |
| |
| } else if (cmd == VFIO_DEVICE_RESET) |
| return vdev->reset_works ? |
| pci_reset_function(vdev->pdev) : -EINVAL; |
| |
| return -ENOTTY; |
| } |
| |
| static ssize_t vfio_pci_rw(void *device_data, char __user *buf, |
| size_t count, loff_t *ppos, bool iswrite) |
| { |
| unsigned int index = VFIO_PCI_OFFSET_TO_INDEX(*ppos); |
| struct vfio_pci_device *vdev = device_data; |
| |
| if (index >= VFIO_PCI_NUM_REGIONS) |
| return -EINVAL; |
| |
| switch (index) { |
| case VFIO_PCI_CONFIG_REGION_INDEX: |
| return vfio_pci_config_rw(vdev, buf, count, ppos, iswrite); |
| |
| case VFIO_PCI_ROM_REGION_INDEX: |
| if (iswrite) |
| return -EINVAL; |
| return vfio_pci_bar_rw(vdev, buf, count, ppos, false); |
| |
| case VFIO_PCI_BAR0_REGION_INDEX ... VFIO_PCI_BAR5_REGION_INDEX: |
| return vfio_pci_bar_rw(vdev, buf, count, ppos, iswrite); |
| |
| case VFIO_PCI_VGA_REGION_INDEX: |
| return vfio_pci_vga_rw(vdev, buf, count, ppos, iswrite); |
| } |
| |
| return -EINVAL; |
| } |
| |
| static ssize_t vfio_pci_read(void *device_data, char __user *buf, |
| size_t count, loff_t *ppos) |
| { |
| if (!count) |
| return 0; |
| |
| return vfio_pci_rw(device_data, buf, count, ppos, false); |
| } |
| |
| static ssize_t vfio_pci_write(void *device_data, const char __user *buf, |
| size_t count, loff_t *ppos) |
| { |
| if (!count) |
| return 0; |
| |
| return vfio_pci_rw(device_data, (char __user *)buf, count, ppos, true); |
| } |
| |
| static int vfio_pci_mmap(void *device_data, struct vm_area_struct *vma) |
| { |
| struct vfio_pci_device *vdev = device_data; |
| struct pci_dev *pdev = vdev->pdev; |
| unsigned int index; |
| u64 phys_len, req_len, pgoff, req_start; |
| int ret; |
| |
| index = vma->vm_pgoff >> (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT); |
| |
| if (vma->vm_end < vma->vm_start) |
| return -EINVAL; |
| if ((vma->vm_flags & VM_SHARED) == 0) |
| return -EINVAL; |
| if (index >= VFIO_PCI_ROM_REGION_INDEX) |
| return -EINVAL; |
| if (!(pci_resource_flags(pdev, index) & IORESOURCE_MEM)) |
| return -EINVAL; |
| |
| phys_len = pci_resource_len(pdev, index); |
| req_len = vma->vm_end - vma->vm_start; |
| pgoff = vma->vm_pgoff & |
| ((1U << (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT)) - 1); |
| req_start = pgoff << PAGE_SHIFT; |
| |
| if (phys_len < PAGE_SIZE || req_start + req_len > phys_len) |
| return -EINVAL; |
| |
| if (index == vdev->msix_bar) { |
| /* |
| * Disallow mmaps overlapping the MSI-X table; users don't |
| * get to touch this directly. We could find somewhere |
| * else to map the overlap, but page granularity is only |
| * a recommendation, not a requirement, so the user needs |
| * to know which bits are real. Requiring them to mmap |
| * around the table makes that clear. |
| */ |
| |
| /* If neither entirely above nor below, then it overlaps */ |
| if (!(req_start >= vdev->msix_offset + vdev->msix_size || |
| req_start + req_len <= vdev->msix_offset)) |
| return -EINVAL; |
| } |
| |
| /* |
| * Even though we don't make use of the barmap for the mmap, |
| * we need to request the region and the barmap tracks that. |
| */ |
| if (!vdev->barmap[index]) { |
| ret = pci_request_selected_regions(pdev, |
| 1 << index, "vfio-pci"); |
| if (ret) |
| return ret; |
| |
| vdev->barmap[index] = pci_iomap(pdev, index, 0); |
| } |
| |
| vma->vm_private_data = vdev; |
| vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP; |
| vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); |
| vma->vm_pgoff = (pci_resource_start(pdev, index) >> PAGE_SHIFT) + pgoff; |
| |
| return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff, |
| req_len, vma->vm_page_prot); |
| } |
| |
| static const struct vfio_device_ops vfio_pci_ops = { |
| .name = "vfio-pci", |
| .open = vfio_pci_open, |
| .release = vfio_pci_release, |
| .ioctl = vfio_pci_ioctl, |
| .read = vfio_pci_read, |
| .write = vfio_pci_write, |
| .mmap = vfio_pci_mmap, |
| }; |
| |
| static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) |
| { |
| u8 type; |
| struct vfio_pci_device *vdev; |
| struct iommu_group *group; |
| int ret; |
| |
| pci_read_config_byte(pdev, PCI_HEADER_TYPE, &type); |
| if ((type & PCI_HEADER_TYPE) != PCI_HEADER_TYPE_NORMAL) |
| return -EINVAL; |
| |
| group = iommu_group_get(&pdev->dev); |
| if (!group) |
| return -EINVAL; |
| |
| vdev = kzalloc(sizeof(*vdev), GFP_KERNEL); |
| if (!vdev) { |
| iommu_group_put(group); |
| return -ENOMEM; |
| } |
| |
| vdev->pdev = pdev; |
| vdev->irq_type = VFIO_PCI_NUM_IRQS; |
| mutex_init(&vdev->igate); |
| spin_lock_init(&vdev->irqlock); |
| atomic_set(&vdev->refcnt, 0); |
| |
| ret = vfio_add_group_dev(&pdev->dev, &vfio_pci_ops, vdev); |
| if (ret) { |
| iommu_group_put(group); |
| kfree(vdev); |
| } |
| |
| return ret; |
| } |
| |
| static void vfio_pci_remove(struct pci_dev *pdev) |
| { |
| struct vfio_pci_device *vdev; |
| |
| vdev = vfio_del_group_dev(&pdev->dev); |
| if (!vdev) |
| return; |
| |
| iommu_group_put(pdev->dev.iommu_group); |
| kfree(vdev); |
| } |
| |
| static struct pci_driver vfio_pci_driver = { |
| .name = "vfio-pci", |
| .id_table = NULL, /* only dynamic ids */ |
| .probe = vfio_pci_probe, |
| .remove = vfio_pci_remove, |
| }; |
| |
| static void __exit vfio_pci_cleanup(void) |
| { |
| pci_unregister_driver(&vfio_pci_driver); |
| vfio_pci_virqfd_exit(); |
| vfio_pci_uninit_perm_bits(); |
| } |
| |
| static int __init vfio_pci_init(void) |
| { |
| int ret; |
| |
| /* Allocate shared config space permision data used by all devices */ |
| ret = vfio_pci_init_perm_bits(); |
| if (ret) |
| return ret; |
| |
| /* Start the virqfd cleanup handler */ |
| ret = vfio_pci_virqfd_init(); |
| if (ret) |
| goto out_virqfd; |
| |
| /* Register and scan for devices */ |
| ret = pci_register_driver(&vfio_pci_driver); |
| if (ret) |
| goto out_driver; |
| |
| return 0; |
| |
| out_driver: |
| vfio_pci_virqfd_exit(); |
| out_virqfd: |
| vfio_pci_uninit_perm_bits(); |
| return ret; |
| } |
| |
| module_init(vfio_pci_init); |
| module_exit(vfio_pci_cleanup); |
| |
| MODULE_VERSION(DRIVER_VERSION); |
| MODULE_LICENSE("GPL v2"); |
| MODULE_AUTHOR(DRIVER_AUTHOR); |
| MODULE_DESCRIPTION(DRIVER_DESC); |