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path: root/drivers/vfio/pci/vfio_pci.c
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Diffstat (limited to 'drivers/vfio/pci/vfio_pci.c')
-rw-r--r--drivers/vfio/pci/vfio_pci.c579
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);