1 files changed, 579 insertions, 0 deletions

diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
new file mode 100644
index 000000000000..6968b7232232
--- /dev/null
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -0,0 +1,579 @@
+/*
+ * 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;
+
+        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)
+                goto out;
+
+        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;
+
+        ret = pci_enable_device(pdev);
+        if (ret)
+                goto out;
+
+        return ret;
+
+out:
+        kfree(vdev->pci_saved_state);
+        vdev->pci_saved_state = NULL;
+        vfio_config_free(vdev);
+        return ret;
+}
+
+static void vfio_pci_disable(struct vfio_pci_device *vdev)
+{
+        int bar;
+
+        pci_disable_device(vdev->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);
+
+        pci_reset_function(vdev->pdev);
+
+        if (pci_load_and_free_saved_state(vdev->pdev,
+                                          &vdev->pci_saved_state) == 0)
+                pci_restore_state(vdev->pdev);
+        else
+                pr_info("%s: Couldn't reload %s saved state\n",
+                        __func__, dev_name(&vdev->pdev->dev));
+
+        for (bar = PCI_STD_RESOURCES; bar <= PCI_STD_RESOURCE_END; bar++) {
+                if (!vdev->barmap[bar])
+                        continue;
+                pci_iounmap(vdev->pdev, vdev->barmap[bar]);
+                pci_release_selected_regions(vdev->pdev, 1 << bar);
+                vdev->barmap[bar] = NULL;
+        }
+}
+
+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 = kmalloc(hdr.count * size, GFP_KERNEL);
+                        if (!data)
+                                return -ENOMEM;
+
+                        if (copy_from_user(data, (void __user *)(arg + minsz),
+                                           hdr.count * size)) {
+                                kfree(data);
+                                return -EFAULT;
+                        }
+                }
+
+                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_read(void *device_data, char __user *buf,
+                             size_t count, loff_t *ppos)
+{
+        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;
+
+        if (index == VFIO_PCI_CONFIG_REGION_INDEX)
+                return vfio_pci_config_readwrite(vdev, buf, count, ppos, false);
+        else if (index == VFIO_PCI_ROM_REGION_INDEX)
+                return vfio_pci_mem_readwrite(vdev, buf, count, ppos, false);
+        else if (pci_resource_flags(pdev, index) & IORESOURCE_IO)
+                return vfio_pci_io_readwrite(vdev, buf, count, ppos, false);
+        else if (pci_resource_flags(pdev, index) & IORESOURCE_MEM)
+                return vfio_pci_mem_readwrite(vdev, buf, count, ppos, false);
+
+        return -EINVAL;
+}
+
+static ssize_t vfio_pci_write(void *device_data, const char __user *buf,
+                              size_t count, loff_t *ppos)
+{
+        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;
+
+        if (index == VFIO_PCI_CONFIG_REGION_INDEX)
+                return vfio_pci_config_readwrite(vdev, (char __user *)buf,
+                                                 count, ppos, true);
+        else if (index == VFIO_PCI_ROM_REGION_INDEX)
+                return -EINVAL;
+        else if (pci_resource_flags(pdev, index) & IORESOURCE_IO)
+                return vfio_pci_io_readwrite(vdev, (char __user *)buf,
+                                             count, ppos, true);
+        else if (pci_resource_flags(pdev, index) & IORESOURCE_MEM) {
+                return vfio_pci_mem_readwrite(vdev, (char __user *)buf,
+                                              count, ppos, true);
+        }
+
+        return -EINVAL;
+}
+
+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, phys;
+        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_RESERVED);
+        vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+
+        phys = (pci_resource_start(pdev, index) >> PAGE_SHIFT) + pgoff;
+
+        return remap_pfn_range(vma, vma->vm_start, phys,
+                               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_virqfd:
+        vfio_pci_virqfd_exit();
+out_driver:
+        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);