vfio: Type1 IOMMU implementation (73fa0d10) · Commits · 戴 / test

drivers/vfio/Kconfig

+6 −0

Original line number	Diff line number	Diff line
		config VFIO_IOMMU_TYPE1
		tristate
		depends on VFIO
		default n

		menuconfig VFIO
		tristate "VFIO Non-Privileged userspace driver framework"
		depends on IOMMU_API
		select VFIO_IOMMU_TYPE1 if X86
		help
		VFIO provides a framework for secure userspace device drivers.
		See Documentation/vfio.txt for more details.

drivers/vfio/Makefile

+2 −0

Original line number	Diff line number	Diff line
		obj-$(CONFIG_VFIO) += vfio.o
		obj-$(CONFIG_VFIO_IOMMU_TYPE1) += vfio_iommu_type1.o
		obj-$(CONFIG_VFIO_PCI) += pci/

drivers/vfio/vfio.c

+7 −0

Original line number	Diff line number	Diff line
		@@ -1376,6 +1376,13 @@ static int __init vfio_init(void)

		pr_info(DRIVER_DESC " version: " DRIVER_VERSION "\n");

		/*
		* Attempt to load known iommu-drivers. This gives us a working
		* environment without the user needing to explicitly load iommu
		* drivers.
		*/
		request_module_nowait("vfio_iommu_type1");

		return 0;

		err_groups_cdev:

drivers/vfio/vfio_iommu_type1.c

0 → 100644

+753 −0

Original line number	Diff line number	Diff line
		/*
		* VFIO: IOMMU DMA mapping support for Type1 IOMMU
		*
		* 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
		*
		* We arbitrarily define a Type1 IOMMU as one matching the below code.
		* It could be called the x86 IOMMU as it's designed for AMD-Vi & Intel
		* VT-d, but that makes it harder to re-use as theoretically anyone
		* implementing a similar IOMMU could make use of this. We expect the
		* IOMMU to support the IOMMU API and have few to no restrictions around
		* the IOVA range that can be mapped. The Type1 IOMMU is currently
		* optimized for relatively static mappings of a userspace process with
		* userpsace pages pinned into memory. We also assume devices and IOMMU
		* domains are PCI based as the IOMMU API is still centered around a
		* device/bus interface rather than a group interface.
		*/

		#include <linux/compat.h>
		#include <linux/device.h>
		#include <linux/fs.h>
		#include <linux/iommu.h>
		#include <linux/module.h>
		#include <linux/mm.h>
		#include <linux/pci.h> /* pci_bus_type */
		#include <linux/sched.h>
		#include <linux/slab.h>
		#include <linux/uaccess.h>
		#include <linux/vfio.h>
		#include <linux/workqueue.h>

		#define DRIVER_VERSION "0.2"
		#define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
		#define DRIVER_DESC "Type1 IOMMU driver for VFIO"

		static bool allow_unsafe_interrupts;
		module_param_named(allow_unsafe_interrupts,
		allow_unsafe_interrupts, bool, S_IRUGO \| S_IWUSR);
		MODULE_PARM_DESC(allow_unsafe_interrupts,
		"Enable VFIO IOMMU support for on platforms without interrupt remapping support.");

		struct vfio_iommu {
		struct iommu_domain *domain;
		struct mutex lock;
		struct list_head dma_list;
		struct list_head group_list;
		bool cache;
		};

		struct vfio_dma {
		struct list_head next;
		dma_addr_t iova; /* Device address */
		unsigned long vaddr; /* Process virtual addr */
		long npage; /* Number of pages */
		int prot; /* IOMMU_READ/WRITE */
		};

		struct vfio_group {
		struct iommu_group *iommu_group;
		struct list_head next;
		};

		/*
		* This code handles mapping and unmapping of user data buffers
		* into DMA'ble space using the IOMMU
		*/

		#define NPAGE_TO_SIZE(npage) ((size_t)(npage) << PAGE_SHIFT)

		struct vwork {
		struct mm_struct *mm;
		long npage;
		struct work_struct work;
		};

		/* delayed decrement/increment for locked_vm */
		static void vfio_lock_acct_bg(struct work_struct *work)
		{
		struct vwork *vwork = container_of(work, struct vwork, work);
		struct mm_struct *mm;

		mm = vwork->mm;
		down_write(&mm->mmap_sem);
		mm->locked_vm += vwork->npage;
		up_write(&mm->mmap_sem);
		mmput(mm);
		kfree(vwork);
		}

		static void vfio_lock_acct(long npage)
		{
		struct vwork *vwork;
		struct mm_struct *mm;

		if (!current->mm)
		return; /* process exited */

		if (down_write_trylock(&current->mm->mmap_sem)) {
		current->mm->locked_vm += npage;
		up_write(&current->mm->mmap_sem);
		return;
		}

		/*
		* Couldn't get mmap_sem lock, so must setup to update
		* mm->locked_vm later. If locked_vm were atomic, we
		* wouldn't need this silliness
		*/
		vwork = kmalloc(sizeof(struct vwork), GFP_KERNEL);
		if (!vwork)
		return;
		mm = get_task_mm(current);
		if (!mm) {
		kfree(vwork);
		return;
		}
		INIT_WORK(&vwork->work, vfio_lock_acct_bg);
		vwork->mm = mm;
		vwork->npage = npage;
		schedule_work(&vwork->work);
		}

		/*
		* Some mappings aren't backed by a struct page, for example an mmap'd
		* MMIO range for our own or another device. These use a different
		* pfn conversion and shouldn't be tracked as locked pages.
		*/
		static bool is_invalid_reserved_pfn(unsigned long pfn)
		{
		if (pfn_valid(pfn)) {
		bool reserved;
		struct page *tail = pfn_to_page(pfn);
		struct page *head = compound_trans_head(tail);
		reserved = !!(PageReserved(head));
		if (head != tail) {
		/*
		* "head" is not a dangling pointer
		* (compound_trans_head takes care of that)
		* but the hugepage may have been split
		* from under us (and we may not hold a
		* reference count on the head page so it can
		* be reused before we run PageReferenced), so
		* we've to check PageTail before returning
		* what we just read.
		*/
		smp_rmb();
		if (PageTail(tail))
		return reserved;
		}
		return PageReserved(tail);
		}

		return true;
		}

		static int put_pfn(unsigned long pfn, int prot)
		{
		if (!is_invalid_reserved_pfn(pfn)) {
		struct page *page = pfn_to_page(pfn);
		if (prot & IOMMU_WRITE)
		SetPageDirty(page);
		put_page(page);
		return 1;
		}
		return 0;
		}

		/* Unmap DMA region */
		static long __vfio_dma_do_unmap(struct vfio_iommu *iommu, dma_addr_t iova,
		long npage, int prot)
		{
		long i, unlocked = 0;

		for (i = 0; i < npage; i++, iova += PAGE_SIZE) {
		unsigned long pfn;

		pfn = iommu_iova_to_phys(iommu->domain, iova) >> PAGE_SHIFT;
		if (pfn) {
		iommu_unmap(iommu->domain, iova, PAGE_SIZE);
		unlocked += put_pfn(pfn, prot);
		}
		}
		return unlocked;
		}

		static void vfio_dma_unmap(struct vfio_iommu *iommu, dma_addr_t iova,
		long npage, int prot)
		{
		long unlocked;

		unlocked = __vfio_dma_do_unmap(iommu, iova, npage, prot);
		vfio_lock_acct(-unlocked);
		}

		static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
		{
		struct page *page[1];
		struct vm_area_struct *vma;
		int ret = -EFAULT;

		if (get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE), page) == 1) {
		*pfn = page_to_pfn(page[0]);
		return 0;
		}

		down_read(&current->mm->mmap_sem);

		vma = find_vma_intersection(current->mm, vaddr, vaddr + 1);

		if (vma && vma->vm_flags & VM_PFNMAP) {
		*pfn = ((vaddr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
		if (is_invalid_reserved_pfn(*pfn))
		ret = 0;
		}

		up_read(&current->mm->mmap_sem);

		return ret;
		}

		/* Map DMA region */
		static int __vfio_dma_map(struct vfio_iommu *iommu, dma_addr_t iova,
		unsigned long vaddr, long npage, int prot)
		{
		dma_addr_t start = iova;
		long i, locked = 0;
		int ret;

		/* Verify that pages are not already mapped */
		for (i = 0; i < npage; i++, iova += PAGE_SIZE)
		if (iommu_iova_to_phys(iommu->domain, iova))
		return -EBUSY;

		iova = start;

		if (iommu->cache)
		prot \|= IOMMU_CACHE;

		/*
		* XXX We break mappings into pages and use get_user_pages_fast to
		* pin the pages in memory. It's been suggested that mlock might
		* provide a more efficient mechanism, but nothing prevents the
		* user from munlocking the pages, which could then allow the user
		* access to random host memory. We also have no guarantee from the
		* IOMMU API that the iommu driver can unmap sub-pages of previous
		* mappings. This means we might lose an entire range if a single
		* page within it is unmapped. Single page mappings are inefficient,
		* but provide the most flexibility for now.
		*/
		for (i = 0; i < npage; i++, iova += PAGE_SIZE, vaddr += PAGE_SIZE) {
		unsigned long pfn = 0;

		ret = vaddr_get_pfn(vaddr, prot, &pfn);
		if (ret) {
		__vfio_dma_do_unmap(iommu, start, i, prot);
		return ret;
		}

		/*
		* Only add actual locked pages to accounting
		* XXX We're effectively marking a page locked for every
		* IOVA page even though it's possible the user could be
		* backing multiple IOVAs with the same vaddr. This over-
		* penalizes the user process, but we currently have no
		* easy way to do this properly.
		*/
		if (!is_invalid_reserved_pfn(pfn))
		locked++;

		ret = iommu_map(iommu->domain, iova,
		(phys_addr_t)pfn << PAGE_SHIFT,
		PAGE_SIZE, prot);
		if (ret) {
		/* Back out mappings on error */
		put_pfn(pfn, prot);
		__vfio_dma_do_unmap(iommu, start, i, prot);
		return ret;
		}
		}
		vfio_lock_acct(locked);
		return 0;
		}

		static inline bool ranges_overlap(dma_addr_t start1, size_t size1,
		dma_addr_t start2, size_t size2)
		{
		if (start1 < start2)
		return (start2 - start1 < size1);
		else if (start2 < start1)
		return (start1 - start2 < size2);
		return (size1 > 0 && size2 > 0);
		}

		static struct vfio_dma vfio_find_dma(struct vfio_iommu iommu,
		dma_addr_t start, size_t size)
		{
		struct vfio_dma *dma;

		list_for_each_entry(dma, &iommu->dma_list, next) {
		if (ranges_overlap(dma->iova, NPAGE_TO_SIZE(dma->npage),
		start, size))
		return dma;
		}
		return NULL;
		}

		static long vfio_remove_dma_overlap(struct vfio_iommu *iommu, dma_addr_t start,
		size_t size, struct vfio_dma *dma)
		{
		struct vfio_dma *split;
		long npage_lo, npage_hi;

		/* Existing dma region is completely covered, unmap all */
		if (start <= dma->iova &&
		start + size >= dma->iova + NPAGE_TO_SIZE(dma->npage)) {
		vfio_dma_unmap(iommu, dma->iova, dma->npage, dma->prot);
		list_del(&dma->next);
		npage_lo = dma->npage;
		kfree(dma);
		return npage_lo;
		}

		/* Overlap low address of existing range */
		if (start <= dma->iova) {
		size_t overlap;

		overlap = start + size - dma->iova;
		npage_lo = overlap >> PAGE_SHIFT;

		vfio_dma_unmap(iommu, dma->iova, npage_lo, dma->prot);
		dma->iova += overlap;
		dma->vaddr += overlap;
		dma->npage -= npage_lo;
		return npage_lo;
		}

		/* Overlap high address of existing range */
		if (start + size >= dma->iova + NPAGE_TO_SIZE(dma->npage)) {
		size_t overlap;

		overlap = dma->iova + NPAGE_TO_SIZE(dma->npage) - start;
		npage_hi = overlap >> PAGE_SHIFT;

		vfio_dma_unmap(iommu, start, npage_hi, dma->prot);
		dma->npage -= npage_hi;
		return npage_hi;
		}

		/* Split existing */
		npage_lo = (start - dma->iova) >> PAGE_SHIFT;
		npage_hi = dma->npage - (size >> PAGE_SHIFT) - npage_lo;

		split = kzalloc(sizeof *split, GFP_KERNEL);
		if (!split)
		return -ENOMEM;

		vfio_dma_unmap(iommu, start, size >> PAGE_SHIFT, dma->prot);

		dma->npage = npage_lo;

		split->npage = npage_hi;
		split->iova = start + size;
		split->vaddr = dma->vaddr + NPAGE_TO_SIZE(npage_lo) + size;
		split->prot = dma->prot;
		list_add(&split->next, &iommu->dma_list);
		return size >> PAGE_SHIFT;
		}

		static int vfio_dma_do_unmap(struct vfio_iommu *iommu,
		struct vfio_iommu_type1_dma_unmap *unmap)
		{
		long ret = 0, npage = unmap->size >> PAGE_SHIFT;
		struct vfio_dma dma, tmp;
		uint64_t mask;

		mask = ((uint64_t)1 << __ffs(iommu->domain->ops->pgsize_bitmap)) - 1;

		if (unmap->iova & mask)
		return -EINVAL;
		if (unmap->size & mask)
		return -EINVAL;

		/* XXX We still break these down into PAGE_SIZE */
		WARN_ON(mask & PAGE_MASK);

		mutex_lock(&iommu->lock);

		list_for_each_entry_safe(dma, tmp, &iommu->dma_list, next) {
		if (ranges_overlap(dma->iova, NPAGE_TO_SIZE(dma->npage),
		unmap->iova, unmap->size)) {
		ret = vfio_remove_dma_overlap(iommu, unmap->iova,
		unmap->size, dma);
		if (ret > 0)
		npage -= ret;
		if (ret < 0 \|\| npage == 0)
		break;
		}
		}
		mutex_unlock(&iommu->lock);
		return ret > 0 ? 0 : (int)ret;
		}

		static int vfio_dma_do_map(struct vfio_iommu *iommu,
		struct vfio_iommu_type1_dma_map *map)
		{
		struct vfio_dma dma, pdma = NULL;
		dma_addr_t iova = map->iova;
		unsigned long locked, lock_limit, vaddr = map->vaddr;
		size_t size = map->size;
		int ret = 0, prot = 0;
		uint64_t mask;
		long npage;

		mask = ((uint64_t)1 << __ffs(iommu->domain->ops->pgsize_bitmap)) - 1;

		/* READ/WRITE from device perspective */
		if (map->flags & VFIO_DMA_MAP_FLAG_WRITE)
		prot \|= IOMMU_WRITE;
		if (map->flags & VFIO_DMA_MAP_FLAG_READ)
		prot \|= IOMMU_READ;

		if (!prot)
		return -EINVAL; /* No READ/WRITE? */

		if (vaddr & mask)
		return -EINVAL;
		if (iova & mask)
		return -EINVAL;
		if (size & mask)
		return -EINVAL;

		/* XXX We still break these down into PAGE_SIZE */
		WARN_ON(mask & PAGE_MASK);

		/* Don't allow IOVA wrap */
		if (iova + size && iova + size < iova)
		return -EINVAL;

		/* Don't allow virtual address wrap */
		if (vaddr + size && vaddr + size < vaddr)
		return -EINVAL;

		npage = size >> PAGE_SHIFT;
		if (!npage)
		return -EINVAL;

		mutex_lock(&iommu->lock);

		if (vfio_find_dma(iommu, iova, size)) {
		ret = -EBUSY;
		goto out_lock;
		}

		/* account for locked pages */
		locked = current->mm->locked_vm + npage;
		lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
		if (locked > lock_limit && !capable(CAP_IPC_LOCK)) {
		pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n",
		__func__, rlimit(RLIMIT_MEMLOCK));
		ret = -ENOMEM;
		goto out_lock;
		}

		ret = __vfio_dma_map(iommu, iova, vaddr, npage, prot);
		if (ret)
		goto out_lock;

		/* Check if we abut a region below - nothing below 0 */
		if (iova) {
		dma = vfio_find_dma(iommu, iova - 1, 1);
		if (dma && dma->prot == prot &&
		dma->vaddr + NPAGE_TO_SIZE(dma->npage) == vaddr) {

		dma->npage += npage;
		iova = dma->iova;
		vaddr = dma->vaddr;
		npage = dma->npage;
		size = NPAGE_TO_SIZE(npage);

		pdma = dma;
		}
		}

		/* Check if we abut a region above - nothing above ~0 + 1 */
		if (iova + size) {
		dma = vfio_find_dma(iommu, iova + size, 1);
		if (dma && dma->prot == prot &&
		dma->vaddr == vaddr + size) {

		dma->npage += npage;
		dma->iova = iova;
		dma->vaddr = vaddr;

		/*
		* If merged above and below, remove previously
		* merged entry. New entry covers it.
		*/
		if (pdma) {
		list_del(&pdma->next);
		kfree(pdma);
		}
		pdma = dma;
		}
		}

		/* Isolated, new region */
		if (!pdma) {
		dma = kzalloc(sizeof *dma, GFP_KERNEL);
		if (!dma) {
		ret = -ENOMEM;
		vfio_dma_unmap(iommu, iova, npage, prot);
		goto out_lock;
		}

		dma->npage = npage;
		dma->iova = iova;
		dma->vaddr = vaddr;
		dma->prot = prot;
		list_add(&dma->next, &iommu->dma_list);
		}

		out_lock:
		mutex_unlock(&iommu->lock);
		return ret;
		}

		static int vfio_iommu_type1_attach_group(void *iommu_data,
		struct iommu_group *iommu_group)
		{
		struct vfio_iommu *iommu = iommu_data;
		struct vfio_group group, tmp;
		int ret;

		group = kzalloc(sizeof(*group), GFP_KERNEL);
		if (!group)
		return -ENOMEM;

		mutex_lock(&iommu->lock);

		list_for_each_entry(tmp, &iommu->group_list, next) {
		if (tmp->iommu_group == iommu_group) {
		mutex_unlock(&iommu->lock);
		kfree(group);
		return -EINVAL;
		}
		}

		/*
		* TODO: Domain have capabilities that might change as we add
		* groups (see iommu->cache, currently never set). Check for
		* them and potentially disallow groups to be attached when it
		* would change capabilities (ugh).
		*/
		ret = iommu_attach_group(iommu->domain, iommu_group);
		if (ret) {
		mutex_unlock(&iommu->lock);
		kfree(group);
		return ret;
		}

		group->iommu_group = iommu_group;
		list_add(&group->next, &iommu->group_list);

		mutex_unlock(&iommu->lock);

		return 0;
		}

		static void vfio_iommu_type1_detach_group(void *iommu_data,
		struct iommu_group *iommu_group)
		{
		struct vfio_iommu *iommu = iommu_data;
		struct vfio_group *group;

		mutex_lock(&iommu->lock);

		list_for_each_entry(group, &iommu->group_list, next) {
		if (group->iommu_group == iommu_group) {
		iommu_detach_group(iommu->domain, iommu_group);
		list_del(&group->next);
		kfree(group);
		break;
		}
		}

		mutex_unlock(&iommu->lock);
		}

		static void *vfio_iommu_type1_open(unsigned long arg)
		{
		struct vfio_iommu *iommu;

		if (arg != VFIO_TYPE1_IOMMU)
		return ERR_PTR(-EINVAL);

		iommu = kzalloc(sizeof(*iommu), GFP_KERNEL);
		if (!iommu)
		return ERR_PTR(-ENOMEM);

		INIT_LIST_HEAD(&iommu->group_list);
		INIT_LIST_HEAD(&iommu->dma_list);
		mutex_init(&iommu->lock);

		/*
		* Wish we didn't have to know about bus_type here.
		*/
		iommu->domain = iommu_domain_alloc(&pci_bus_type);
		if (!iommu->domain) {
		kfree(iommu);
		return ERR_PTR(-EIO);
		}

		/*
		* Wish we could specify required capabilities rather than create
		* a domain, see what comes out and hope it doesn't change along
		* the way. Fortunately we know interrupt remapping is global for
		* our iommus.
		*/
		if (!allow_unsafe_interrupts &&
		!iommu_domain_has_cap(iommu->domain, IOMMU_CAP_INTR_REMAP)) {
		pr_warn("%s: No interrupt remapping support. Use the module param \"allow_unsafe_interrupts\" to enable VFIO IOMMU support on this platform\n",
		__func__);
		iommu_domain_free(iommu->domain);
		kfree(iommu);
		return ERR_PTR(-EPERM);
		}

		return iommu;
		}

		static void vfio_iommu_type1_release(void *iommu_data)
		{
		struct vfio_iommu *iommu = iommu_data;
		struct vfio_group group, group_tmp;
		struct vfio_dma dma, dma_tmp;

		list_for_each_entry_safe(group, group_tmp, &iommu->group_list, next) {
		iommu_detach_group(iommu->domain, group->iommu_group);
		list_del(&group->next);
		kfree(group);
		}

		list_for_each_entry_safe(dma, dma_tmp, &iommu->dma_list, next) {
		vfio_dma_unmap(iommu, dma->iova, dma->npage, dma->prot);
		list_del(&dma->next);
		kfree(dma);
		}

		iommu_domain_free(iommu->domain);
		iommu->domain = NULL;
		kfree(iommu);
		}

		static long vfio_iommu_type1_ioctl(void *iommu_data,
		unsigned int cmd, unsigned long arg)
		{
		struct vfio_iommu *iommu = iommu_data;
		unsigned long minsz;

		if (cmd == VFIO_CHECK_EXTENSION) {
		switch (arg) {
		case VFIO_TYPE1_IOMMU:
		return 1;
		default:
		return 0;
		}
		} else if (cmd == VFIO_IOMMU_GET_INFO) {
		struct vfio_iommu_type1_info info;

		minsz = offsetofend(struct vfio_iommu_type1_info, iova_pgsizes);

		if (copy_from_user(&info, (void __user *)arg, minsz))
		return -EFAULT;

		if (info.argsz < minsz)
		return -EINVAL;

		info.flags = 0;

		info.iova_pgsizes = iommu->domain->ops->pgsize_bitmap;

		return copy_to_user((void __user *)arg, &info, minsz);

		} else if (cmd == VFIO_IOMMU_MAP_DMA) {
		struct vfio_iommu_type1_dma_map map;
		uint32_t mask = VFIO_DMA_MAP_FLAG_READ \|
		VFIO_DMA_MAP_FLAG_WRITE;

		minsz = offsetofend(struct vfio_iommu_type1_dma_map, size);

		if (copy_from_user(&map, (void __user *)arg, minsz))
		return -EFAULT;

		if (map.argsz < minsz \|\| map.flags & ~mask)
		return -EINVAL;

		return vfio_dma_do_map(iommu, &map);

		} else if (cmd == VFIO_IOMMU_UNMAP_DMA) {
		struct vfio_iommu_type1_dma_unmap unmap;

		minsz = offsetofend(struct vfio_iommu_type1_dma_unmap, size);

		if (copy_from_user(&unmap, (void __user *)arg, minsz))
		return -EFAULT;

		if (unmap.argsz < minsz \|\| unmap.flags)
		return -EINVAL;

		return vfio_dma_do_unmap(iommu, &unmap);
		}

		return -ENOTTY;
		}

		static const struct vfio_iommu_driver_ops vfio_iommu_driver_ops_type1 = {
		.name = "vfio-iommu-type1",
		.owner = THIS_MODULE,
		.open = vfio_iommu_type1_open,
		.release = vfio_iommu_type1_release,
		.ioctl = vfio_iommu_type1_ioctl,
		.attach_group = vfio_iommu_type1_attach_group,
		.detach_group = vfio_iommu_type1_detach_group,
		};

		static int __init vfio_iommu_type1_init(void)
		{
		if (!iommu_present(&pci_bus_type))
		return -ENODEV;

		return vfio_register_iommu_driver(&vfio_iommu_driver_ops_type1);
		}

		static void __exit vfio_iommu_type1_cleanup(void)
		{
		vfio_unregister_iommu_driver(&vfio_iommu_driver_ops_type1);
		}

		module_init(vfio_iommu_type1_init);
		module_exit(vfio_iommu_type1_cleanup);

		MODULE_VERSION(DRIVER_VERSION);
		MODULE_LICENSE("GPL v2");
		MODULE_AUTHOR(DRIVER_AUTHOR);
		MODULE_DESCRIPTION(DRIVER_DESC);

include/linux/vfio.h

+53 −1

Original line number	Diff line number	Diff line
		@@ -98,7 +98,7 @@ extern void vfio_unregister_iommu_driver(

		/* Extensions */

		/* None yet */
		#define VFIO_TYPE1_IOMMU 1

		/*
		* The IOCTL interface is designed for extensibility by embedding the
		@@ -364,4 +364,56 @@ struct vfio_irq_set {
		*/
		#define VFIO_DEVICE_RESET _IO(VFIO_TYPE, VFIO_BASE + 11)

		/* -------- API for Type1 VFIO IOMMU -------- */

		/**
		* VFIO_IOMMU_GET_INFO - _IOR(VFIO_TYPE, VFIO_BASE + 12, struct vfio_iommu_info)
		*
		* Retrieve information about the IOMMU object. Fills in provided
		* struct vfio_iommu_info. Caller sets argsz.
		*
		* XXX Should we do these by CHECK_EXTENSION too?
		*/
		struct vfio_iommu_type1_info {
		__u32 argsz;
		__u32 flags;
		#define VFIO_IOMMU_INFO_PGSIZES (1 << 0) /* supported page sizes info */
		__u64 iova_pgsizes; /* Bitmap of supported page sizes */
		};

		#define VFIO_IOMMU_GET_INFO _IO(VFIO_TYPE, VFIO_BASE + 12)

		/**
		* VFIO_IOMMU_MAP_DMA - _IOW(VFIO_TYPE, VFIO_BASE + 13, struct vfio_dma_map)
		*
		* Map process virtual addresses to IO virtual addresses using the
		* provided struct vfio_dma_map. Caller sets argsz. READ &/ WRITE required.
		*/
		struct vfio_iommu_type1_dma_map {
		__u32 argsz;
		__u32 flags;
		#define VFIO_DMA_MAP_FLAG_READ (1 << 0) /* readable from device */
		#define VFIO_DMA_MAP_FLAG_WRITE (1 << 1) /* writable from device */
		__u64 vaddr; /* Process virtual address */
		__u64 iova; /* IO virtual address */
		__u64 size; /* Size of mapping (bytes) */
		};

		#define VFIO_IOMMU_MAP_DMA _IO(VFIO_TYPE, VFIO_BASE + 13)

		/**
		* VFIO_IOMMU_UNMAP_DMA - _IOW(VFIO_TYPE, VFIO_BASE + 14, struct vfio_dma_unmap)
		*
		* Unmap IO virtual addresses using the provided struct vfio_dma_unmap.
		* Caller sets argsz.
		*/
		struct vfio_iommu_type1_dma_unmap {
		__u32 argsz;
		__u32 flags;
		__u64 iova; /* IO virtual address */
		__u64 size; /* Size of mapping (bytes) */
		};

		#define VFIO_IOMMU_UNMAP_DMA _IO(VFIO_TYPE, VFIO_BASE + 14)

		#endif /* VFIO_H */

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