/* * Copyright (C) 2012 Red Hat, Inc. All rights reserved. * Author: Alex Williamson * * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include "vfio_pci_private.h" #define DRIVER_VERSION "0.2" #define DRIVER_AUTHOR "Alex Williamson " #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_FLAGS_BIRMASK; vdev->msix_offset = table & ~PCI_MSIX_FLAGS_BIRMASK; vdev->msix_size = ((flags & PCI_MSIX_FLAGS_QSIZE) + 1) * 16; } else vdev->msix_bar = 0xFF; 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; } 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; struct pci_dev *pdev = vdev->pdev; if (index >= VFIO_PCI_NUM_REGIONS) return -EINVAL; switch (index) { case VFIO_PCI_CONFIG_REGION_INDEX: return vfio_pci_config_readwrite(vdev, buf, count, ppos, iswrite); case VFIO_PCI_ROM_REGION_INDEX: if (iswrite) return -EINVAL; return vfio_pci_mem_readwrite(vdev, buf, count, ppos, false); case VFIO_PCI_BAR0_REGION_INDEX ... VFIO_PCI_BAR5_REGION_INDEX: { unsigned long flags = pci_resource_flags(pdev, index); if (flags & IORESOURCE_IO) return vfio_pci_io_readwrite(vdev, buf, count, ppos, iswrite); if (flags & IORESOURCE_MEM) return vfio_pci_mem_readwrite(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) { 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) { return vfio_pci_rw(device_data, 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);