mirror of
https://github.com/torvalds/linux.git
synced 2024-11-26 06:02:05 +00:00
vfio: Type1 IOMMU implementation
This VFIO IOMMU backend is designed primarily for AMD-Vi and Intel VT-d hardware, but is potentially usable by anything supporting similar mapping functionality. We arbitrarily call this a Type1 backend for lack of a better name. This backend has no IOVA or host memory mapping restrictions for the user and is optimized for relatively static mappings. Mapped areas are pinned into system memory. Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This commit is contained in:
Alex Williamson
parent
4a5b2a20ec
commit
73fa0d10d0
@ -1,6 +1,12 @@
|
||||
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.
|
||||
|
||||
@ -1 +1,3 @@
|
||||
obj-$(CONFIG_VFIO) += vfio.o
|
||||
obj-$(CONFIG_VFIO_IOMMU_TYPE1) += vfio_iommu_type1.o
|
||||
obj-$(CONFIG_VFIO_PCI) += pci/
|
||||
|
||||
@ -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:
|
||||
|
||||
753
drivers/vfio/vfio_iommu_type1.c
Normal file
753
drivers/vfio/vfio_iommu_type1.c
Normal file
@ -0,0 +1,753 @@
|
||||
/*
|
||||
* 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(¤t->mm->mmap_sem)) {
|
||||
current->mm->locked_vm += npage;
|
||||
up_write(¤t->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(¤t->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(¤t->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);
|
||||
@ -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 */
|
||||
|
||||
Loading…
Reference in New Issue
Block a user