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VFIO for v3.6 

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Merge tag 'vfio-for-v3.6' of git://github.com/awilliam/linux-vfio

Pull VFIO core from Alex Williamson:
 "This series includes the VFIO userspace driver interface for the 3.6
  kernel merge window.  This driver is intended to provide a secure
  interface for device access using IOMMU protection for applications
  like assignment of physical devices to virtual machines.

  Qemu will be the first user of this interface, enabling assignment of
  PCI devices to Qemu guests.  This interface is intended to eventually
  replace the x86-specific assignment mechanism currently available in
  KVM.

  This interface has the advantage of being more secure, by working with
  IOMMU groups to ensure device isolation and providing it's own
  filtered resource access mechanism, and also more flexible, in not
  being x86 or KVM specific (extensions to enable POWER are already
  working).

  This driver is originally the work of Tom Lyon, but has since been
  handed over to me and gone through a complete overhaul thanks to the
  input from David Gibson, Ben Herrenschmidt, Chris Wright, Joerg
  Roedel, and others.  This driver has been available in linux-next for
  the last month."

Paul Mackerras says:
 "I would be glad to see it go in since we want to use it with KVM on
  PowerPC.  If possible we'd like the PowerPC bits for it to go in as
  well."

* tag 'vfio-for-v3.6' of git://github.com/awilliam/linux-vfio:
  vfio: Add PCI device driver
  vfio: Type1 IOMMU implementation
  vfio: Add documentation
  vfio: VFIO core
This commit is contained in:
Linus Torvalds 2012-07-31 19:17:27 -07:00
parent 3e9a97082f 89e1f7d4c6
commit a40a1d3d0a
17 changed files with 6194 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
Documentation/ioctl/ioctl-number.txt
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@ -88,6 +88,7 @@ Code Seq#(hex) Include File Comments
and kernel/power/user.c
'8' all SNP8023 advanced NIC card
<mailto:mcr@solidum.com>
';' 64-7F linux/vfio.h
'@' 00-0F linux/radeonfb.h conflict!
'@' 00-0F drivers/video/aty/aty128fb.c conflict!
'A' 00-1F linux/apm_bios.h conflict!

314
Documentation/vfio.txt Normal file
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@ -0,0 +1,314 @@
VFIO - "Virtual Function I/O"[1]
-------------------------------------------------------------------------------
Many modern system now provide DMA and interrupt remapping facilities
to help ensure I/O devices behave within the boundaries they've been
allotted. This includes x86 hardware with AMD-Vi and Intel VT-d,
POWER systems with Partitionable Endpoints (PEs) and embedded PowerPC
systems such as Freescale PAMU. The VFIO driver is an IOMMU/device
agnostic framework for exposing direct device access to userspace, in
a secure, IOMMU protected environment. In other words, this allows
safe[2], non-privileged, userspace drivers.
Why do we want that? Virtual machines often make use of direct device
access ("device assignment") when configured for the highest possible
I/O performance. From a device and host perspective, this simply
turns the VM into a userspace driver, with the benefits of
significantly reduced latency, higher bandwidth, and direct use of
bare-metal device drivers[3].
Some applications, particularly in the high performance computing
field, also benefit from low-overhead, direct device access from
userspace. Examples include network adapters (often non-TCP/IP based)
and compute accelerators. Prior to VFIO, these drivers had to either
go through the full development cycle to become proper upstream
driver, be maintained out of tree, or make use of the UIO framework,
which has no notion of IOMMU protection, limited interrupt support,
and requires root privileges to access things like PCI configuration
space.
The VFIO driver framework intends to unify these, replacing both the
KVM PCI specific device assignment code as well as provide a more
secure, more featureful userspace driver environment than UIO.
Groups, Devices, and IOMMUs
-------------------------------------------------------------------------------
Devices are the main target of any I/O driver. Devices typically
create a programming interface made up of I/O access, interrupts,
and DMA. Without going into the details of each of these, DMA is
by far the most critical aspect for maintaining a secure environment
as allowing a device read-write access to system memory imposes the
greatest risk to the overall system integrity.
To help mitigate this risk, many modern IOMMUs now incorporate
isolation properties into what was, in many cases, an interface only
meant for translation (ie. solving the addressing problems of devices
with limited address spaces). With this, devices can now be isolated
from each other and from arbitrary memory access, thus allowing
things like secure direct assignment of devices into virtual machines.
This isolation is not always at the granularity of a single device
though. Even when an IOMMU is capable of this, properties of devices,
interconnects, and IOMMU topologies can each reduce this isolation.
For instance, an individual device may be part of a larger multi-
function enclosure. While the IOMMU may be able to distinguish
between devices within the enclosure, the enclosure may not require
transactions between devices to reach the IOMMU. Examples of this
could be anything from a multi-function PCI device with backdoors
between functions to a non-PCI-ACS (Access Control Services) capable
bridge allowing redirection without reaching the IOMMU. Topology
can also play a factor in terms of hiding devices. A PCIe-to-PCI
bridge masks the devices behind it, making transaction appear as if
from the bridge itself. Obviously IOMMU design plays a major factor
as well.
Therefore, while for the most part an IOMMU may have device level
granularity, any system is susceptible to reduced granularity. The
IOMMU API therefore supports a notion of IOMMU groups. A group is
a set of devices which is isolatable from all other devices in the
system. Groups are therefore the unit of ownership used by VFIO.
While the group is the minimum granularity that must be used to
ensure secure user access, it's not necessarily the preferred
granularity. In IOMMUs which make use of page tables, it may be
possible to share a set of page tables between different groups,
reducing the overhead both to the platform (reduced TLB thrashing,
reduced duplicate page tables), and to the user (programming only
a single set of translations). For this reason, VFIO makes use of
a container class, which may hold one or more groups. A container
is created by simply opening the /dev/vfio/vfio character device.
On its own, the container provides little functionality, with all
but a couple version and extension query interfaces locked away.
The user needs to add a group into the container for the next level
of functionality. To do this, the user first needs to identify the
group associated with the desired device. This can be done using
the sysfs links described in the example below. By unbinding the
device from the host driver and binding it to a VFIO driver, a new
VFIO group will appear for the group as /dev/vfio/$GROUP, where
$GROUP is the IOMMU group number of which the device is a member.
If the IOMMU group contains multiple devices, each will need to
be bound to a VFIO driver before operations on the VFIO group
are allowed (it's also sufficient to only unbind the device from
host drivers if a VFIO driver is unavailable; this will make the
group available, but not that particular device). TBD - interface
for disabling driver probing/locking a device.
Once the group is ready, it may be added to the container by opening
the VFIO group character device (/dev/vfio/$GROUP) and using the
VFIO_GROUP_SET_CONTAINER ioctl, passing the file descriptor of the
previously opened container file. If desired and if the IOMMU driver
supports sharing the IOMMU context between groups, multiple groups may
be set to the same container. If a group fails to set to a container
with existing groups, a new empty container will need to be used
instead.
With a group (or groups) attached to a container, the remaining
ioctls become available, enabling access to the VFIO IOMMU interfaces.
Additionally, it now becomes possible to get file descriptors for each
device within a group using an ioctl on the VFIO group file descriptor.
The VFIO device API includes ioctls for describing the device, the I/O
regions and their read/write/mmap offsets on the device descriptor, as
well as mechanisms for describing and registering interrupt
notifications.
VFIO Usage Example
-------------------------------------------------------------------------------
Assume user wants to access PCI device 0000:06:0d.0
$ readlink /sys/bus/pci/devices/0000:06:0d.0/iommu_group
../../../../kernel/iommu_groups/26
This device is therefore in IOMMU group 26. This device is on the
pci bus, therefore the user will make use of vfio-pci to manage the
group:
# modprobe vfio-pci
Binding this device to the vfio-pci driver creates the VFIO group
character devices for this group:
$ lspci -n -s 0000:06:0d.0
06:0d.0 0401: 1102:0002 (rev 08)
# echo 0000:06:0d.0 > /sys/bus/pci/devices/0000:06:0d.0/driver/unbind
# echo 1102 0002 > /sys/bus/pci/drivers/vfio/new_id
Now we need to look at what other devices are in the group to free
it for use by VFIO:
$ ls -l /sys/bus/pci/devices/0000:06:0d.0/iommu_group/devices
total 0
lrwxrwxrwx. 1 root root 0 Apr 23 16:13 0000:00:1e.0 ->
../../../../devices/pci0000:00/0000:00:1e.0
lrwxrwxrwx. 1 root root 0 Apr 23 16:13 0000:06:0d.0 ->
../../../../devices/pci0000:00/0000:00:1e.0/0000:06:0d.0
lrwxrwxrwx. 1 root root 0 Apr 23 16:13 0000:06:0d.1 ->
../../../../devices/pci0000:00/0000:00:1e.0/0000:06:0d.1
This device is behind a PCIe-to-PCI bridge[4], therefore we also
need to add device 0000:06:0d.1 to the group following the same
procedure as above. Device 0000:00:1e.0 is a bridge that does
not currently have a host driver, therefore it's not required to
bind this device to the vfio-pci driver (vfio-pci does not currently
support PCI bridges).
The final step is to provide the user with access to the group if
unprivileged operation is desired (note that /dev/vfio/vfio provides
no capabilities on its own and is therefore expected to be set to
mode 0666 by the system).
# chown user:user /dev/vfio/26
The user now has full access to all the devices and the iommu for this
group and can access them as follows:
int container, group, device, i;
struct vfio_group_status group_status =
{ .argsz = sizeof(group_status) };
struct vfio_iommu_x86_info iommu_info = { .argsz = sizeof(iommu_info) };
struct vfio_iommu_x86_dma_map dma_map = { .argsz = sizeof(dma_map) };
struct vfio_device_info device_info = { .argsz = sizeof(device_info) };
/* Create a new container */
container = open("/dev/vfio/vfio, O_RDWR);
if (ioctl(container, VFIO_GET_API_VERSION) != VFIO_API_VERSION)
/* Unknown API version */
if (!ioctl(container, VFIO_CHECK_EXTENSION, VFIO_X86_IOMMU))
/* Doesn't support the IOMMU driver we want. */
/* Open the group */
group = open("/dev/vfio/26", O_RDWR);
/* Test the group is viable and available */
ioctl(group, VFIO_GROUP_GET_STATUS, &group_status);
if (!(group_status.flags & VFIO_GROUP_FLAGS_VIABLE))
/* Group is not viable (ie, not all devices bound for vfio) */
/* Add the group to the container */
ioctl(group, VFIO_GROUP_SET_CONTAINER, &container);
/* Enable the IOMMU model we want */
ioctl(container, VFIO_SET_IOMMU, VFIO_X86_IOMMU)
/* Get addition IOMMU info */
ioctl(container, VFIO_IOMMU_GET_INFO, &iommu_info);
/* Allocate some space and setup a DMA mapping */
dma_map.vaddr = mmap(0, 1024 * 1024, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
dma_map.size = 1024 * 1024;
dma_map.iova = 0; /* 1MB starting at 0x0 from device view */
dma_map.flags = VFIO_DMA_MAP_FLAG_READ | VFIO_DMA_MAP_FLAG_WRITE;
ioctl(container, VFIO_IOMMU_MAP_DMA, &dma_map);
/* Get a file descriptor for the device */
device = ioctl(group, VFIO_GROUP_GET_DEVICE_FD, "0000:06:0d.0");
/* Test and setup the device */
ioctl(device, VFIO_DEVICE_GET_INFO, &device_info);
for (i = 0; i < device_info.num_regions; i++) {
struct vfio_region_info reg = { .argsz = sizeof(reg) };
reg.index = i;
ioctl(device, VFIO_DEVICE_GET_REGION_INFO, &reg);
/* Setup mappings... read/write offsets, mmaps
* For PCI devices, config space is a region */
}
for (i = 0; i < device_info.num_irqs; i++) {
struct vfio_irq_info irq = { .argsz = sizeof(irq) };
irq.index = i;
ioctl(device, VFIO_DEVICE_GET_IRQ_INFO, &reg);
/* Setup IRQs... eventfds, VFIO_DEVICE_SET_IRQS */
}
/* Gratuitous device reset and go... */
ioctl(device, VFIO_DEVICE_RESET);
VFIO User API
-------------------------------------------------------------------------------
Please see include/linux/vfio.h for complete API documentation.
VFIO bus driver API
-------------------------------------------------------------------------------
VFIO bus drivers, such as vfio-pci make use of only a few interfaces
into VFIO core. When devices are bound and unbound to the driver,
the driver should call vfio_add_group_dev() and vfio_del_group_dev()
respectively:
extern int vfio_add_group_dev(struct iommu_group *iommu_group,
struct device *dev,
const struct vfio_device_ops *ops,
void *device_data);
extern void *vfio_del_group_dev(struct device *dev);
vfio_add_group_dev() indicates to the core to begin tracking the
specified iommu_group and register the specified dev as owned by
a VFIO bus driver. The driver provides an ops structure for callbacks
similar to a file operations structure:
struct vfio_device_ops {
int (*open)(void *device_data);
void (*release)(void *device_data);
ssize_t (*read)(void *device_data, char __user *buf,
size_t count, loff_t *ppos);
ssize_t (*write)(void *device_data, const char __user *buf,
size_t size, loff_t *ppos);
long (*ioctl)(void *device_data, unsigned int cmd,
unsigned long arg);
int (*mmap)(void *device_data, struct vm_area_struct *vma);
};
Each function is passed the device_data that was originally registered
in the vfio_add_group_dev() call above. This allows the bus driver
an easy place to store its opaque, private data. The open/release
callbacks are issued when a new file descriptor is created for a
device (via VFIO_GROUP_GET_DEVICE_FD). The ioctl interface provides
a direct pass through for VFIO_DEVICE_* ioctls. The read/write/mmap
interfaces implement the device region access defined by the device's
own VFIO_DEVICE_GET_REGION_INFO ioctl.
-------------------------------------------------------------------------------
[1] VFIO was originally an acronym for "Virtual Function I/O" in its
initial implementation by Tom Lyon while as Cisco. We've since
outgrown the acronym, but it's catchy.
[2] "safe" also depends upon a device being "well behaved". It's
possible for multi-function devices to have backdoors between
functions and even for single function devices to have alternative
access to things like PCI config space through MMIO registers. To
guard against the former we can include additional precautions in the
IOMMU driver to group multi-function PCI devices together
(iommu=group_mf). The latter we can't prevent, but the IOMMU should
still provide isolation. For PCI, SR-IOV Virtual Functions are the
best indicator of "well behaved", as these are designed for
virtualization usage models.
[3] As always there are trade-offs to virtual machine device
assignment that are beyond the scope of VFIO. It's expected that
future IOMMU technologies will reduce some, but maybe not all, of
these trade-offs.
[4] In this case the device is below a PCI bridge, so transactions
from either function of the device are indistinguishable to the iommu:
-[0000:00]-+-1e.0-[06]--+-0d.0
\-0d.1
00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev 90)

8
MAINTAINERS
View File

@ -7414,6 +7414,14 @@ S: Maintained
F: Documentation/filesystems/vfat.txt
F: fs/fat/
VFIO DRIVER
M: Alex Williamson <alex.williamson@redhat.com>
L: kvm@vger.kernel.org
S: Maintained
F: Documentation/vfio.txt
F: drivers/vfio/
F: include/linux/vfio.h
VIDEOBUF2 FRAMEWORK
M: Pawel Osciak <pawel@osciak.com>
M: Marek Szyprowski <m.szyprowski@samsung.com>

2
drivers/Kconfig
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@ -112,6 +112,8 @@ source "drivers/auxdisplay/Kconfig"
source "drivers/uio/Kconfig"
source "drivers/vfio/Kconfig"
source "drivers/vlynq/Kconfig"
source "drivers/virtio/Kconfig"

1
drivers/Makefile
View File

@ -60,6 +60,7 @@ obj-$(CONFIG_ATM) += atm/
obj-$(CONFIG_FUSION) += message/
obj-y += firewire/
obj-$(CONFIG_UIO) += uio/
obj-$(CONFIG_VFIO) += vfio/
obj-y += cdrom/
obj-y += auxdisplay/
obj-$(CONFIG_PCCARD) += pcmcia/

16
drivers/vfio/Kconfig Normal file
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@ -0,0 +1,16 @@
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.
If you don't know what to do here, say N.
source "drivers/vfio/pci/Kconfig"

3
drivers/vfio/Makefile Normal file
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@ -0,0 +1,3 @@
obj-$(CONFIG_VFIO) += vfio.o
obj-$(CONFIG_VFIO_IOMMU_TYPE1) += vfio_iommu_type1.o
obj-$(CONFIG_VFIO_PCI) += pci/

8
drivers/vfio/pci/Kconfig Normal file
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@ -0,0 +1,8 @@
config VFIO_PCI
tristate "VFIO support for PCI devices"
depends on VFIO && PCI && EVENTFD
help
Support for the PCI VFIO bus driver. This is required to make
use of PCI drivers using the VFIO framework.
If you don't know what to do here, say N.

4
drivers/vfio/pci/Makefile Normal file
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@ -0,0 +1,4 @@
vfio-pci-y := vfio_pci.o vfio_pci_intrs.o vfio_pci_rdwr.o vfio_pci_config.o
obj-$(CONFIG_VFIO_PCI) += vfio-pci.o

579
drivers/vfio/pci/vfio_pci.c Normal file
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@ -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);

1540
drivers/vfio/pci/vfio_pci_config.c Normal file
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740
drivers/vfio/pci/vfio_pci_intrs.c Normal file
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@ -0,0 +1,740 @@
/*
* VFIO PCI interrupt handling
*
* 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/interrupt.h>
#include <linux/eventfd.h>
#include <linux/pci.h>
#include <linux/file.h>
#include <linux/poll.h>
#include <linux/vfio.h>
#include <linux/wait.h>
#include <linux/workqueue.h>
#include "vfio_pci_private.h"
/*
* IRQfd - generic
*/
struct virqfd {
struct vfio_pci_device *vdev;
struct eventfd_ctx *eventfd;
int (*handler)(struct vfio_pci_device *, void *);
void (*thread)(struct vfio_pci_device *, void *);
void *data;
struct work_struct inject;
wait_queue_t wait;
poll_table pt;
struct work_struct shutdown;
struct virqfd **pvirqfd;
};
static struct workqueue_struct *vfio_irqfd_cleanup_wq;
int __init vfio_pci_virqfd_init(void)
{
vfio_irqfd_cleanup_wq =
create_singlethread_workqueue("vfio-irqfd-cleanup");
if (!vfio_irqfd_cleanup_wq)
return -ENOMEM;
return 0;
}
void vfio_pci_virqfd_exit(void)
{
destroy_workqueue(vfio_irqfd_cleanup_wq);
}
static void virqfd_deactivate(struct virqfd *virqfd)
{
queue_work(vfio_irqfd_cleanup_wq, &virqfd->shutdown);
}
static int virqfd_wakeup(wait_queue_t *wait, unsigned mode, int sync, void *key)
{
struct virqfd *virqfd = container_of(wait, struct virqfd, wait);
unsigned long flags = (unsigned long)key;
if (flags & POLLIN) {
/* An event has been signaled, call function */
if ((!virqfd->handler ||
virqfd->handler(virqfd->vdev, virqfd->data)) &&
virqfd->thread)
schedule_work(&virqfd->inject);
}
if (flags & POLLHUP)
/* The eventfd is closing, detach from VFIO */
virqfd_deactivate(virqfd);
return 0;
}
static void virqfd_ptable_queue_proc(struct file *file,
wait_queue_head_t *wqh, poll_table *pt)
{
struct virqfd *virqfd = container_of(pt, struct virqfd, pt);
add_wait_queue(wqh, &virqfd->wait);
}
static void virqfd_shutdown(struct work_struct *work)
{
struct virqfd *virqfd = container_of(work, struct virqfd, shutdown);
struct virqfd **pvirqfd = virqfd->pvirqfd;
u64 cnt;
eventfd_ctx_remove_wait_queue(virqfd->eventfd, &virqfd->wait, &cnt);
flush_work(&virqfd->inject);
eventfd_ctx_put(virqfd->eventfd);
kfree(virqfd);
*pvirqfd = NULL;
}
static void virqfd_inject(struct work_struct *work)
{
struct virqfd *virqfd = container_of(work, struct virqfd, inject);
if (virqfd->thread)
virqfd->thread(virqfd->vdev, virqfd->data);
}
static int virqfd_enable(struct vfio_pci_device *vdev,
int (*handler)(struct vfio_pci_device *, void *),
void (*thread)(struct vfio_pci_device *, void *),
void *data, struct virqfd **pvirqfd, int fd)
{
struct file *file = NULL;
struct eventfd_ctx *ctx = NULL;
struct virqfd *virqfd;
int ret = 0;
unsigned int events;
if (*pvirqfd)
return -EBUSY;
virqfd = kzalloc(sizeof(*virqfd), GFP_KERNEL);
if (!virqfd)
return -ENOMEM;
virqfd->pvirqfd = pvirqfd;
*pvirqfd = virqfd;
virqfd->vdev = vdev;
virqfd->handler = handler;
virqfd->thread = thread;
virqfd->data = data;
INIT_WORK(&virqfd->shutdown, virqfd_shutdown);
INIT_WORK(&virqfd->inject, virqfd_inject);
file = eventfd_fget(fd);
if (IS_ERR(file)) {
ret = PTR_ERR(file);
goto fail;
}
ctx = eventfd_ctx_fileget(file);
if (IS_ERR(ctx)) {
ret = PTR_ERR(ctx);
goto fail;
}
virqfd->eventfd = ctx;
/*
* Install our own custom wake-up handling so we are notified via
* a callback whenever someone signals the underlying eventfd.
*/
init_waitqueue_func_entry(&virqfd->wait, virqfd_wakeup);
init_poll_funcptr(&virqfd->pt, virqfd_ptable_queue_proc);
events = file->f_op->poll(file, &virqfd->pt);
/*
* Check if there was an event already pending on the eventfd
* before we registered and trigger it as if we didn't miss it.
*/
if (events & POLLIN) {
if ((!handler || handler(vdev, data)) && thread)
schedule_work(&virqfd->inject);
}
/*
* Do not drop the file until the irqfd is fully initialized,
* otherwise we might race against the POLLHUP.
*/
fput(file);
return 0;
fail:
if (ctx && !IS_ERR(ctx))
eventfd_ctx_put(ctx);
if (file && !IS_ERR(file))
fput(file);
kfree(virqfd);
*pvirqfd = NULL;
return ret;
}
static void virqfd_disable(struct virqfd *virqfd)
{
if (!virqfd)
return;
virqfd_deactivate(virqfd);
/* Block until we know all outstanding shutdown jobs have completed. */
flush_workqueue(vfio_irqfd_cleanup_wq);
}
/*
* INTx
*/
static void vfio_send_intx_eventfd(struct vfio_pci_device *vdev, void *unused)
{
if (likely(is_intx(vdev) && !vdev->virq_disabled))
eventfd_signal(vdev->ctx[0].trigger, 1);
}
void vfio_pci_intx_mask(struct vfio_pci_device *vdev)
{
struct pci_dev *pdev = vdev->pdev;
unsigned long flags;
spin_lock_irqsave(&vdev->irqlock, flags);
/*
* Masking can come from interrupt, ioctl, or config space
* via INTx disable. The latter means this can get called
* even when not using intx delivery. In this case, just
* try to have the physical bit follow the virtual bit.
*/
if (unlikely(!is_intx(vdev))) {
if (vdev->pci_2_3)
pci_intx(pdev, 0);
} else if (!vdev->ctx[0].masked) {
/*
* Can't use check_and_mask here because we always want to
* mask, not just when something is pending.
*/
if (vdev->pci_2_3)
pci_intx(pdev, 0);
else
disable_irq_nosync(pdev->irq);
vdev->ctx[0].masked = true;
}
spin_unlock_irqrestore(&vdev->irqlock, flags);
}
/*
* If this is triggered by an eventfd, we can't call eventfd_signal
* or else we'll deadlock on the eventfd wait queue. Return >0 when
* a signal is necessary, which can then be handled via a work queue
* or directly depending on the caller.
*/
int vfio_pci_intx_unmask_handler(struct vfio_pci_device *vdev, void *unused)
{
struct pci_dev *pdev = vdev->pdev;
unsigned long flags;
int ret = 0;
spin_lock_irqsave(&vdev->irqlock, flags);
/*
* Unmasking comes from ioctl or config, so again, have the
* physical bit follow the virtual even when not using INTx.
*/
if (unlikely(!is_intx(vdev))) {
if (vdev->pci_2_3)
pci_intx(pdev, 1);
} else if (vdev->ctx[0].masked && !vdev->virq_disabled) {
/*
* A pending interrupt here would immediately trigger,
* but we can avoid that overhead by just re-sending
* the interrupt to the user.
*/
if (vdev->pci_2_3) {
if (!pci_check_and_unmask_intx(pdev))
ret = 1;
} else
enable_irq(pdev->irq);
vdev->ctx[0].masked = (ret > 0);
}
spin_unlock_irqrestore(&vdev->irqlock, flags);
return ret;
}
void vfio_pci_intx_unmask(struct vfio_pci_device *vdev)
{
if (vfio_pci_intx_unmask_handler(vdev, NULL) > 0)
vfio_send_intx_eventfd(vdev, NULL);
}
static irqreturn_t vfio_intx_handler(int irq, void *dev_id)
{
struct vfio_pci_device *vdev = dev_id;
unsigned long flags;
int ret = IRQ_NONE;
spin_lock_irqsave(&vdev->irqlock, flags);
if (!vdev->pci_2_3) {
disable_irq_nosync(vdev->pdev->irq);
vdev->ctx[0].masked = true;
ret = IRQ_HANDLED;
} else if (!vdev->ctx[0].masked && /* may be shared */
pci_check_and_mask_intx(vdev->pdev)) {
vdev->ctx[0].masked = true;
ret = IRQ_HANDLED;
}
spin_unlock_irqrestore(&vdev->irqlock, flags);
if (ret == IRQ_HANDLED)
vfio_send_intx_eventfd(vdev, NULL);
return ret;
}
static int vfio_intx_enable(struct vfio_pci_device *vdev)
{
if (!is_irq_none(vdev))
return -EINVAL;
if (!vdev->pdev->irq)
return -ENODEV;
vdev->ctx = kzalloc(sizeof(struct vfio_pci_irq_ctx), GFP_KERNEL);
if (!vdev->ctx)
return -ENOMEM;
vdev->num_ctx = 1;
vdev->irq_type = VFIO_PCI_INTX_IRQ_INDEX;
return 0;
}
static int vfio_intx_set_signal(struct vfio_pci_device *vdev, int fd)
{
struct pci_dev *pdev = vdev->pdev;
unsigned long irqflags = IRQF_SHARED;
struct eventfd_ctx *trigger;
unsigned long flags;
int ret;
if (vdev->ctx[0].trigger) {
free_irq(pdev->irq, vdev);
kfree(vdev->ctx[0].name);
eventfd_ctx_put(vdev->ctx[0].trigger);
vdev->ctx[0].trigger = NULL;
}
if (fd < 0) /* Disable only */
return 0;
vdev->ctx[0].name = kasprintf(GFP_KERNEL, "vfio-intx(%s)",
pci_name(pdev));
if (!vdev->ctx[0].name)
return -ENOMEM;
trigger = eventfd_ctx_fdget(fd);
if (IS_ERR(trigger)) {
kfree(vdev->ctx[0].name);
return PTR_ERR(trigger);
}
if (!vdev->pci_2_3)
irqflags = 0;
ret = request_irq(pdev->irq, vfio_intx_handler,
irqflags, vdev->ctx[0].name, vdev);
if (ret) {
kfree(vdev->ctx[0].name);
eventfd_ctx_put(trigger);
return ret;
}
vdev->ctx[0].trigger = trigger;
/*
* INTx disable will stick across the new irq setup,
* disable_irq won't.
*/
spin_lock_irqsave(&vdev->irqlock, flags);
if (!vdev->pci_2_3 && (vdev->ctx[0].masked || vdev->virq_disabled))
disable_irq_nosync(pdev->irq);
spin_unlock_irqrestore(&vdev->irqlock, flags);
return 0;
}
static void vfio_intx_disable(struct vfio_pci_device *vdev)
{
vfio_intx_set_signal(vdev, -1);
virqfd_disable(vdev->ctx[0].unmask);
virqfd_disable(vdev->ctx[0].mask);
vdev->irq_type = VFIO_PCI_NUM_IRQS;
vdev->num_ctx = 0;
kfree(vdev->ctx);
}
/*
* MSI/MSI-X
*/
static irqreturn_t vfio_msihandler(int irq, void *arg)
{
struct eventfd_ctx *trigger = arg;
eventfd_signal(trigger, 1);
return IRQ_HANDLED;
}
static int vfio_msi_enable(struct vfio_pci_device *vdev, int nvec, bool msix)
{
struct pci_dev *pdev = vdev->pdev;
int ret;
if (!is_irq_none(vdev))
return -EINVAL;
vdev->ctx = kzalloc(nvec * sizeof(struct vfio_pci_irq_ctx), GFP_KERNEL);
if (!vdev->ctx)
return -ENOMEM;
if (msix) {
int i;
vdev->msix = kzalloc(nvec * sizeof(struct msix_entry),
GFP_KERNEL);
if (!vdev->msix) {
kfree(vdev->ctx);
return -ENOMEM;
}
for (i = 0; i < nvec; i++)
vdev->msix[i].entry = i;
ret = pci_enable_msix(pdev, vdev->msix, nvec);
if (ret) {
kfree(vdev->msix);
kfree(vdev->ctx);
return ret;
}
} else {
ret = pci_enable_msi_block(pdev, nvec);
if (ret) {
kfree(vdev->ctx);
return ret;
}
}
vdev->num_ctx = nvec;
vdev->irq_type = msix ? VFIO_PCI_MSIX_IRQ_INDEX :
VFIO_PCI_MSI_IRQ_INDEX;
if (!msix) {
/*
* Compute the virtual hardware field for max msi vectors -
* it is the log base 2 of the number of vectors.
*/
vdev->msi_qmax = fls(nvec * 2 - 1) - 1;
}
return 0;
}
static int vfio_msi_set_vector_signal(struct vfio_pci_device *vdev,
int vector, int fd, bool msix)
{
struct pci_dev *pdev = vdev->pdev;
int irq = msix ? vdev->msix[vector].vector : pdev->irq + vector;
char *name = msix ? "vfio-msix" : "vfio-msi";
struct eventfd_ctx *trigger;
int ret;
if (vector >= vdev->num_ctx)
return -EINVAL;
if (vdev->ctx[vector].trigger) {
free_irq(irq, vdev->ctx[vector].trigger);
kfree(vdev->ctx[vector].name);
eventfd_ctx_put(vdev->ctx[vector].trigger);
vdev->ctx[vector].trigger = NULL;
}
if (fd < 0)
return 0;
vdev->ctx[vector].name = kasprintf(GFP_KERNEL, "%s[%d](%s)",
name, vector, pci_name(pdev));
if (!vdev->ctx[vector].name)
return -ENOMEM;
trigger = eventfd_ctx_fdget(fd);
if (IS_ERR(trigger)) {
kfree(vdev->ctx[vector].name);
return PTR_ERR(trigger);
}
ret = request_irq(irq, vfio_msihandler, 0,
vdev->ctx[vector].name, trigger);
if (ret) {
kfree(vdev->ctx[vector].name);
eventfd_ctx_put(trigger);
return ret;
}
vdev->ctx[vector].trigger = trigger;
return 0;
}
static int vfio_msi_set_block(struct vfio_pci_device *vdev, unsigned start,
unsigned count, int32_t *fds, bool msix)
{
int i, j, ret = 0;
if (start + count > vdev->num_ctx)
return -EINVAL;
for (i = 0, j = start; i < count && !ret; i++, j++) {
int fd = fds ? fds[i] : -1;
ret = vfio_msi_set_vector_signal(vdev, j, fd, msix);
}
if (ret) {
for (--j; j >= start; j--)
vfio_msi_set_vector_signal(vdev, j, -1, msix);
}
return ret;
}
static void vfio_msi_disable(struct vfio_pci_device *vdev, bool msix)
{
struct pci_dev *pdev = vdev->pdev;
int i;
vfio_msi_set_block(vdev, 0, vdev->num_ctx, NULL, msix);
for (i = 0; i < vdev->num_ctx; i++) {
virqfd_disable(vdev->ctx[i].unmask);
virqfd_disable(vdev->ctx[i].mask);
}
if (msix) {
pci_disable_msix(vdev->pdev);
kfree(vdev->msix);
} else
pci_disable_msi(pdev);
vdev->irq_type = VFIO_PCI_NUM_IRQS;
vdev->num_ctx = 0;
kfree(vdev->ctx);
}
/*
* IOCTL support
*/
static int vfio_pci_set_intx_unmask(struct vfio_pci_device *vdev,
unsigned index, unsigned start,
unsigned count, uint32_t flags, void *data)
{
if (!is_intx(vdev) || start != 0 || count != 1)
return -EINVAL;
if (flags & VFIO_IRQ_SET_DATA_NONE) {
vfio_pci_intx_unmask(vdev);
} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
uint8_t unmask = *(uint8_t *)data;
if (unmask)
vfio_pci_intx_unmask(vdev);
} else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
int32_t fd = *(int32_t *)data;
if (fd >= 0)
return virqfd_enable(vdev, vfio_pci_intx_unmask_handler,
vfio_send_intx_eventfd, NULL,
&vdev->ctx[0].unmask, fd);
virqfd_disable(vdev->ctx[0].unmask);
}
return 0;
}
static int vfio_pci_set_intx_mask(struct vfio_pci_device *vdev,
unsigned index, unsigned start,
unsigned count, uint32_t flags, void *data)
{
if (!is_intx(vdev) || start != 0 || count != 1)
return -EINVAL;
if (flags & VFIO_IRQ_SET_DATA_NONE) {
vfio_pci_intx_mask(vdev);
} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
uint8_t mask = *(uint8_t *)data;
if (mask)
vfio_pci_intx_mask(vdev);
} else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
return -ENOTTY; /* XXX implement me */
}
return 0;
}
static int vfio_pci_set_intx_trigger(struct vfio_pci_device *vdev,
unsigned index, unsigned start,
unsigned count, uint32_t flags, void *data)
{
if (is_intx(vdev) && !count && (flags & VFIO_IRQ_SET_DATA_NONE)) {
vfio_intx_disable(vdev);
return 0;
}
if (!(is_intx(vdev) || is_irq_none(vdev)) || start != 0 || count != 1)
return -EINVAL;
if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
int32_t fd = *(int32_t *)data;
int ret;
if (is_intx(vdev))
return vfio_intx_set_signal(vdev, fd);
ret = vfio_intx_enable(vdev);
if (ret)
return ret;
ret = vfio_intx_set_signal(vdev, fd);
if (ret)
vfio_intx_disable(vdev);
return ret;
}
if (!is_intx(vdev))
return -EINVAL;
if (flags & VFIO_IRQ_SET_DATA_NONE) {
vfio_send_intx_eventfd(vdev, NULL);
} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
uint8_t trigger = *(uint8_t *)data;
if (trigger)
vfio_send_intx_eventfd(vdev, NULL);
}
return 0;
}
static int vfio_pci_set_msi_trigger(struct vfio_pci_device *vdev,
unsigned index, unsigned start,
unsigned count, uint32_t flags, void *data)
{
int i;
bool msix = (index == VFIO_PCI_MSIX_IRQ_INDEX) ? true : false;
if (irq_is(vdev, index) && !count && (flags & VFIO_IRQ_SET_DATA_NONE)) {
vfio_msi_disable(vdev, msix);
return 0;
}
if (!(irq_is(vdev, index) || is_irq_none(vdev)))
return -EINVAL;
if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
int32_t *fds = data;
int ret;
if (vdev->irq_type == index)
return vfio_msi_set_block(vdev, start, count,
fds, msix);
ret = vfio_msi_enable(vdev, start + count, msix);
if (ret)
return ret;
ret = vfio_msi_set_block(vdev, start, count, fds, msix);
if (ret)
vfio_msi_disable(vdev, msix);
return ret;
}
if (!irq_is(vdev, index) || start + count > vdev->num_ctx)
return -EINVAL;
for (i = start; i < start + count; i++) {
if (!vdev->ctx[i].trigger)
continue;
if (flags & VFIO_IRQ_SET_DATA_NONE) {
eventfd_signal(vdev->ctx[i].trigger, 1);
} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
uint8_t *bools = data;
if (bools[i - start])
eventfd_signal(vdev->ctx[i].trigger, 1);
}
}
return 0;
}
int vfio_pci_set_irqs_ioctl(struct vfio_pci_device *vdev, uint32_t flags,
unsigned index, unsigned start, unsigned count,
void *data)
{
int (*func)(struct vfio_pci_device *vdev, unsigned index,
unsigned start, unsigned count, uint32_t flags,
void *data) = NULL;
switch (index) {
case VFIO_PCI_INTX_IRQ_INDEX:
switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
case VFIO_IRQ_SET_ACTION_MASK:
func = vfio_pci_set_intx_mask;
break;
case VFIO_IRQ_SET_ACTION_UNMASK:
func = vfio_pci_set_intx_unmask;
break;
case VFIO_IRQ_SET_ACTION_TRIGGER:
func = vfio_pci_set_intx_trigger;
break;
}
break;
case VFIO_PCI_MSI_IRQ_INDEX:
case VFIO_PCI_MSIX_IRQ_INDEX:
switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
case VFIO_IRQ_SET_ACTION_MASK:
case VFIO_IRQ_SET_ACTION_UNMASK:
/* XXX Need masking support exported */
break;
case VFIO_IRQ_SET_ACTION_TRIGGER:
func = vfio_pci_set_msi_trigger;
break;
}
break;
}
if (!func)
return -ENOTTY;
return func(vdev, index, start, count, flags, data);
}

91
drivers/vfio/pci/vfio_pci_private.h Normal file
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/*
* 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/mutex.h>
#include <linux/pci.h>
#ifndef VFIO_PCI_PRIVATE_H
#define VFIO_PCI_PRIVATE_H
#define VFIO_PCI_OFFSET_SHIFT 40
#define VFIO_PCI_OFFSET_TO_INDEX(off) (off >> VFIO_PCI_OFFSET_SHIFT)
#define VFIO_PCI_INDEX_TO_OFFSET(index) ((u64)(index) << VFIO_PCI_OFFSET_SHIFT)
#define VFIO_PCI_OFFSET_MASK (((u64)(1) << VFIO_PCI_OFFSET_SHIFT) - 1)
struct vfio_pci_irq_ctx {
struct eventfd_ctx *trigger;
struct virqfd *unmask;
struct virqfd *mask;
char *name;
bool masked;
};
struct vfio_pci_device {
struct pci_dev *pdev;
void __iomem *barmap[PCI_STD_RESOURCE_END + 1];
u8 *pci_config_map;
u8 *vconfig;
struct perm_bits *msi_perm;
spinlock_t irqlock;
struct mutex igate;
struct msix_entry *msix;
struct vfio_pci_irq_ctx *ctx;
int num_ctx;
int irq_type;
u8 msi_qmax;
u8 msix_bar;
u16 msix_size;
u32 msix_offset;
u32 rbar[7];
bool pci_2_3;
bool virq_disabled;
bool reset_works;
bool extended_caps;
bool bardirty;
struct pci_saved_state *pci_saved_state;
atomic_t refcnt;
};
#define is_intx(vdev) (vdev->irq_type == VFIO_PCI_INTX_IRQ_INDEX)
#define is_msi(vdev) (vdev->irq_type == VFIO_PCI_MSI_IRQ_INDEX)
#define is_msix(vdev) (vdev->irq_type == VFIO_PCI_MSIX_IRQ_INDEX)
#define is_irq_none(vdev) (!(is_intx(vdev) || is_msi(vdev) || is_msix(vdev)))
#define irq_is(vdev, type) (vdev->irq_type == type)
extern void vfio_pci_intx_mask(struct vfio_pci_device *vdev);
extern void vfio_pci_intx_unmask(struct vfio_pci_device *vdev);
extern int vfio_pci_set_irqs_ioctl(struct vfio_pci_device *vdev,
uint32_t flags, unsigned index,
unsigned start, unsigned count, void *data);
extern ssize_t vfio_pci_config_readwrite(struct vfio_pci_device *vdev,
char __user *buf, size_t count,
loff_t *ppos, bool iswrite);
extern ssize_t vfio_pci_mem_readwrite(struct vfio_pci_device *vdev,
char __user *buf, size_t count,
loff_t *ppos, bool iswrite);
extern ssize_t vfio_pci_io_readwrite(struct vfio_pci_device *vdev,
char __user *buf, size_t count,
loff_t *ppos, bool iswrite);
extern int vfio_pci_init_perm_bits(void);
extern void vfio_pci_uninit_perm_bits(void);
extern int vfio_pci_virqfd_init(void);
extern void vfio_pci_virqfd_exit(void);
extern int vfio_config_init(struct vfio_pci_device *vdev);
extern void vfio_config_free(struct vfio_pci_device *vdev);
#endif /* VFIO_PCI_PRIVATE_H */

269
drivers/vfio/pci/vfio_pci_rdwr.c Normal file
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@ -0,0 +1,269 @@
/*
* VFIO PCI I/O Port & MMIO access
*
* 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/fs.h>
#include <linux/pci.h>
#include <linux/uaccess.h>
#include <linux/io.h>
#include "vfio_pci_private.h"
/* I/O Port BAR access */
ssize_t vfio_pci_io_readwrite(struct vfio_pci_device *vdev, char __user *buf,
size_t count, loff_t *ppos, bool iswrite)
{
struct pci_dev *pdev = vdev->pdev;
loff_t pos = *ppos & VFIO_PCI_OFFSET_MASK;
int bar = VFIO_PCI_OFFSET_TO_INDEX(*ppos);
void __iomem *io;
size_t done = 0;
if (!pci_resource_start(pdev, bar))
return -EINVAL;
if (pos + count > pci_resource_len(pdev, bar))
return -EINVAL;
if (!vdev->barmap[bar]) {
int ret;
ret = pci_request_selected_regions(pdev, 1 << bar, "vfio");
if (ret)
return ret;
vdev->barmap[bar] = pci_iomap(pdev, bar, 0);
if (!vdev->barmap[bar]) {
pci_release_selected_regions(pdev, 1 << bar);
return -EINVAL;
}
}
io = vdev->barmap[bar];
while (count) {
int filled;
if (count >= 3 && !(pos % 4)) {
__le32 val;
if (iswrite) {
if (copy_from_user(&val, buf, 4))
return -EFAULT;
iowrite32(le32_to_cpu(val), io + pos);
} else {
val = cpu_to_le32(ioread32(io + pos));
if (copy_to_user(buf, &val, 4))
return -EFAULT;
}
filled = 4;
} else if ((pos % 2) == 0 && count >= 2) {
__le16 val;
if (iswrite) {
if (copy_from_user(&val, buf, 2))
return -EFAULT;
iowrite16(le16_to_cpu(val), io + pos);
} else {
val = cpu_to_le16(ioread16(io + pos));
if (copy_to_user(buf, &val, 2))
return -EFAULT;
}
filled = 2;
} else {
u8 val;
if (iswrite) {
if (copy_from_user(&val, buf, 1))
return -EFAULT;
iowrite8(val, io + pos);
} else {
val = ioread8(io + pos);
if (copy_to_user(buf, &val, 1))
return -EFAULT;
}
filled = 1;
}
count -= filled;
done += filled;
buf += filled;
pos += filled;
}
*ppos += done;
return done;
}
/*
* MMIO BAR access
* We handle two excluded ranges here as well, if the user tries to read
* the ROM beyond what PCI tells us is available or the MSI-X table region,
* we return 0xFF and writes are dropped.
*/
ssize_t vfio_pci_mem_readwrite(struct vfio_pci_device *vdev, char __user *buf,
size_t count, loff_t *ppos, bool iswrite)
{
struct pci_dev *pdev = vdev->pdev;
loff_t pos = *ppos & VFIO_PCI_OFFSET_MASK;
int bar = VFIO_PCI_OFFSET_TO_INDEX(*ppos);
void __iomem *io;
resource_size_t end;
size_t done = 0;
size_t x_start = 0, x_end = 0; /* excluded range */
if (!pci_resource_start(pdev, bar))
return -EINVAL;
end = pci_resource_len(pdev, bar);
if (pos > end)
return -EINVAL;
if (pos == end)
return 0;
if (pos + count > end)
count = end - pos;
if (bar == PCI_ROM_RESOURCE) {
io = pci_map_rom(pdev, &x_start);
x_end = end;
} else {
if (!vdev->barmap[bar]) {
int ret;
ret = pci_request_selected_regions(pdev, 1 << bar,
"vfio");
if (ret)
return ret;
vdev->barmap[bar] = pci_iomap(pdev, bar, 0);
if (!vdev->barmap[bar]) {
pci_release_selected_regions(pdev, 1 << bar);
return -EINVAL;
}
}
io = vdev->barmap[bar];
if (bar == vdev->msix_bar) {
x_start = vdev->msix_offset;
x_end = vdev->msix_offset + vdev->msix_size;
}
}
if (!io)
return -EINVAL;
while (count) {
size_t fillable, filled;
if (pos < x_start)
fillable = x_start - pos;
else if (pos >= x_end)
fillable = end - pos;
else
fillable = 0;
if (fillable >= 4 && !(pos % 4) && (count >= 4)) {
__le32 val;
if (iswrite) {
if (copy_from_user(&val, buf, 4))
goto out;
iowrite32(le32_to_cpu(val), io + pos);
} else {
val = cpu_to_le32(ioread32(io + pos));
if (copy_to_user(buf, &val, 4))
goto out;
}
filled = 4;
} else if (fillable >= 2 && !(pos % 2) && (count >= 2)) {
__le16 val;
if (iswrite) {
if (copy_from_user(&val, buf, 2))
goto out;
iowrite16(le16_to_cpu(val), io + pos);
} else {
val = cpu_to_le16(ioread16(io + pos));
if (copy_to_user(buf, &val, 2))
goto out;
}
filled = 2;
} else if (fillable) {
u8 val;
if (iswrite) {
if (copy_from_user(&val, buf, 1))
goto out;
iowrite8(val, io + pos);
} else {
val = ioread8(io + pos);
if (copy_to_user(buf, &val, 1))
goto out;
}
filled = 1;
} else {
/* Drop writes, fill reads with FF */
if (!iswrite) {
char val = 0xFF;
size_t i;
for (i = 0; i < x_end - pos; i++) {
if (put_user(val, buf + i))
goto out;
}
}
filled = x_end - pos;
}
count -= filled;
done += filled;
buf += filled;
pos += filled;
}
*ppos += done;
out:
if (bar == PCI_ROM_RESOURCE)
pci_unmap_rom(pdev, io);
return count ? -EFAULT : done;
}

1420
drivers/vfio/vfio.c Normal file
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753
drivers/vfio/vfio_iommu_type1.c Normal file
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@ -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(&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);

445
include/linux/vfio.h Normal file
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@ -0,0 +1,445 @@
/*
* VFIO API definition
*
* 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.
*/
#ifndef VFIO_H
#define VFIO_H
#include <linux/types.h>
#include <linux/ioctl.h>
#define VFIO_API_VERSION 0
#ifdef __KERNEL__ /* Internal VFIO-core/bus driver API */
#include <linux/iommu.h>
#include <linux/mm.h>
/**
* struct vfio_device_ops - VFIO bus driver device callbacks
*
* @open: Called when userspace creates new file descriptor for device
* @release: Called when userspace releases file descriptor for device
* @read: Perform read(2) on device file descriptor
* @write: Perform write(2) on device file descriptor
* @ioctl: Perform ioctl(2) on device file descriptor, supporting VFIO_DEVICE_*
* operations documented below
* @mmap: Perform mmap(2) on a region of the device file descriptor
*/
struct vfio_device_ops {
char *name;
int (*open)(void *device_data);
void (*release)(void *device_data);
ssize_t (*read)(void *device_data, char __user *buf,
size_t count, loff_t *ppos);
ssize_t (*write)(void *device_data, const char __user *buf,
size_t count, loff_t *size);
long (*ioctl)(void *device_data, unsigned int cmd,
unsigned long arg);
int (*mmap)(void *device_data, struct vm_area_struct *vma);
};
extern int vfio_add_group_dev(struct device *dev,
const struct vfio_device_ops *ops,
void *device_data);
extern void *vfio_del_group_dev(struct device *dev);
/**
* struct vfio_iommu_driver_ops - VFIO IOMMU driver callbacks
*/
struct vfio_iommu_driver_ops {
char *name;
struct module *owner;
void *(*open)(unsigned long arg);
void (*release)(void *iommu_data);
ssize_t (*read)(void *iommu_data, char __user *buf,
size_t count, loff_t *ppos);
ssize_t (*write)(void *iommu_data, const char __user *buf,
size_t count, loff_t *size);
long (*ioctl)(void *iommu_data, unsigned int cmd,
unsigned long arg);
int (*mmap)(void *iommu_data, struct vm_area_struct *vma);
int (*attach_group)(void *iommu_data,
struct iommu_group *group);
void (*detach_group)(void *iommu_data,
struct iommu_group *group);
};
extern int vfio_register_iommu_driver(const struct vfio_iommu_driver_ops *ops);
extern void vfio_unregister_iommu_driver(
const struct vfio_iommu_driver_ops *ops);
/**
* offsetofend(TYPE, MEMBER)
*
* @TYPE: The type of the structure
* @MEMBER: The member within the structure to get the end offset of
*
* Simple helper macro for dealing with variable sized structures passed
* from user space. This allows us to easily determine if the provided
* structure is sized to include various fields.
*/
#define offsetofend(TYPE, MEMBER) ({ \
TYPE tmp; \
offsetof(TYPE, MEMBER) + sizeof(tmp.MEMBER); }) \
#endif /* __KERNEL__ */
/* Kernel & User level defines for VFIO IOCTLs. */
/* Extensions */
#define VFIO_TYPE1_IOMMU 1
/*
* The IOCTL interface is designed for extensibility by embedding the
* structure length (argsz) and flags into structures passed between
* kernel and userspace. We therefore use the _IO() macro for these
* defines to avoid implicitly embedding a size into the ioctl request.
* As structure fields are added, argsz will increase to match and flag
* bits will be defined to indicate additional fields with valid data.
* It's *always* the caller's responsibility to indicate the size of
* the structure passed by setting argsz appropriately.
*/
#define VFIO_TYPE (';')
#define VFIO_BASE 100
/* -------- IOCTLs for VFIO file descriptor (/dev/vfio/vfio) -------- */
/**
* VFIO_GET_API_VERSION - _IO(VFIO_TYPE, VFIO_BASE + 0)
*
* Report the version of the VFIO API. This allows us to bump the entire
* API version should we later need to add or change features in incompatible
* ways.
* Return: VFIO_API_VERSION
* Availability: Always
*/
#define VFIO_GET_API_VERSION _IO(VFIO_TYPE, VFIO_BASE + 0)
/**
* VFIO_CHECK_EXTENSION - _IOW(VFIO_TYPE, VFIO_BASE + 1, __u32)
*
* Check whether an extension is supported.
* Return: 0 if not supported, 1 (or some other positive integer) if supported.
* Availability: Always
*/
#define VFIO_CHECK_EXTENSION _IO(VFIO_TYPE, VFIO_BASE + 1)
/**
* VFIO_SET_IOMMU - _IOW(VFIO_TYPE, VFIO_BASE + 2, __s32)
*
* Set the iommu to the given type. The type must be supported by an
* iommu driver as verified by calling CHECK_EXTENSION using the same
* type. A group must be set to this file descriptor before this
* ioctl is available. The IOMMU interfaces enabled by this call are
* specific to the value set.
* Return: 0 on success, -errno on failure
* Availability: When VFIO group attached
*/
#define VFIO_SET_IOMMU _IO(VFIO_TYPE, VFIO_BASE + 2)
/* -------- IOCTLs for GROUP file descriptors (/dev/vfio/$GROUP) -------- */
/**
* VFIO_GROUP_GET_STATUS - _IOR(VFIO_TYPE, VFIO_BASE + 3,
* struct vfio_group_status)
*
* Retrieve information about the group. Fills in provided
* struct vfio_group_info. Caller sets argsz.
* Return: 0 on succes, -errno on failure.
* Availability: Always
*/
struct vfio_group_status {
__u32 argsz;
__u32 flags;
#define VFIO_GROUP_FLAGS_VIABLE (1 << 0)
#define VFIO_GROUP_FLAGS_CONTAINER_SET (1 << 1)
};
#define VFIO_GROUP_GET_STATUS _IO(VFIO_TYPE, VFIO_BASE + 3)
/**
* VFIO_GROUP_SET_CONTAINER - _IOW(VFIO_TYPE, VFIO_BASE + 4, __s32)
*
* Set the container for the VFIO group to the open VFIO file
* descriptor provided. Groups may only belong to a single
* container. Containers may, at their discretion, support multiple
* groups. Only when a container is set are all of the interfaces
* of the VFIO file descriptor and the VFIO group file descriptor
* available to the user.
* Return: 0 on success, -errno on failure.
* Availability: Always
*/
#define VFIO_GROUP_SET_CONTAINER _IO(VFIO_TYPE, VFIO_BASE + 4)
/**
* VFIO_GROUP_UNSET_CONTAINER - _IO(VFIO_TYPE, VFIO_BASE + 5)
*
* Remove the group from the attached container. This is the
* opposite of the SET_CONTAINER call and returns the group to
* an initial state. All device file descriptors must be released
* prior to calling this interface. When removing the last group
* from a container, the IOMMU will be disabled and all state lost,
* effectively also returning the VFIO file descriptor to an initial
* state.
* Return: 0 on success, -errno on failure.
* Availability: When attached to container
*/
#define VFIO_GROUP_UNSET_CONTAINER _IO(VFIO_TYPE, VFIO_BASE + 5)
/**
* VFIO_GROUP_GET_DEVICE_FD - _IOW(VFIO_TYPE, VFIO_BASE + 6, char)
*
* Return a new file descriptor for the device object described by
* the provided string. The string should match a device listed in
* the devices subdirectory of the IOMMU group sysfs entry. The
* group containing the device must already be added to this context.
* Return: new file descriptor on success, -errno on failure.
* Availability: When attached to container
*/
#define VFIO_GROUP_GET_DEVICE_FD _IO(VFIO_TYPE, VFIO_BASE + 6)
/* --------------- IOCTLs for DEVICE file descriptors --------------- */
/**
* VFIO_DEVICE_GET_INFO - _IOR(VFIO_TYPE, VFIO_BASE + 7,
* struct vfio_device_info)
*
* Retrieve information about the device. Fills in provided
* struct vfio_device_info. Caller sets argsz.
* Return: 0 on success, -errno on failure.
*/
struct vfio_device_info {
__u32 argsz;
__u32 flags;
#define VFIO_DEVICE_FLAGS_RESET (1 << 0) /* Device supports reset */
#define VFIO_DEVICE_FLAGS_PCI (1 << 1) /* vfio-pci device */
__u32 num_regions; /* Max region index + 1 */
__u32 num_irqs; /* Max IRQ index + 1 */
};
#define VFIO_DEVICE_GET_INFO _IO(VFIO_TYPE, VFIO_BASE + 7)
/**
* VFIO_DEVICE_GET_REGION_INFO - _IOWR(VFIO_TYPE, VFIO_BASE + 8,
* struct vfio_region_info)
*
* Retrieve information about a device region. Caller provides
* struct vfio_region_info with index value set. Caller sets argsz.
* Implementation of region mapping is bus driver specific. This is
* intended to describe MMIO, I/O port, as well as bus specific
* regions (ex. PCI config space). Zero sized regions may be used
* to describe unimplemented regions (ex. unimplemented PCI BARs).
* Return: 0 on success, -errno on failure.
*/
struct vfio_region_info {
__u32 argsz;
__u32 flags;
#define VFIO_REGION_INFO_FLAG_READ (1 << 0) /* Region supports read */
#define VFIO_REGION_INFO_FLAG_WRITE (1 << 1) /* Region supports write */
#define VFIO_REGION_INFO_FLAG_MMAP (1 << 2) /* Region supports mmap */
__u32 index; /* Region index */
__u32 resv; /* Reserved for alignment */
__u64 size; /* Region size (bytes) */
__u64 offset; /* Region offset from start of device fd */
};
#define VFIO_DEVICE_GET_REGION_INFO _IO(VFIO_TYPE, VFIO_BASE + 8)
/**
* VFIO_DEVICE_GET_IRQ_INFO - _IOWR(VFIO_TYPE, VFIO_BASE + 9,
* struct vfio_irq_info)
*
* Retrieve information about a device IRQ. Caller provides
* struct vfio_irq_info with index value set. Caller sets argsz.
* Implementation of IRQ mapping is bus driver specific. Indexes
* using multiple IRQs are primarily intended to support MSI-like
* interrupt blocks. Zero count irq blocks may be used to describe
* unimplemented interrupt types.
*
* The EVENTFD flag indicates the interrupt index supports eventfd based
* signaling.
*
* The MASKABLE flags indicates the index supports MASK and UNMASK
* actions described below.
*
* AUTOMASKED indicates that after signaling, the interrupt line is
* automatically masked by VFIO and the user needs to unmask the line
* to receive new interrupts. This is primarily intended to distinguish
* level triggered interrupts.
*
* The NORESIZE flag indicates that the interrupt lines within the index
* are setup as a set and new subindexes cannot be enabled without first
* disabling the entire index. This is used for interrupts like PCI MSI
* and MSI-X where the driver may only use a subset of the available
* indexes, but VFIO needs to enable a specific number of vectors
* upfront. In the case of MSI-X, where the user can enable MSI-X and
* then add and unmask vectors, it's up to userspace to make the decision
* whether to allocate the maximum supported number of vectors or tear
* down setup and incrementally increase the vectors as each is enabled.
*/
struct vfio_irq_info {
__u32 argsz;
__u32 flags;
#define VFIO_IRQ_INFO_EVENTFD (1 << 0)
#define VFIO_IRQ_INFO_MASKABLE (1 << 1)
#define VFIO_IRQ_INFO_AUTOMASKED (1 << 2)
#define VFIO_IRQ_INFO_NORESIZE (1 << 3)
__u32 index; /* IRQ index */
__u32 count; /* Number of IRQs within this index */
};
#define VFIO_DEVICE_GET_IRQ_INFO _IO(VFIO_TYPE, VFIO_BASE + 9)
/**
* VFIO_DEVICE_SET_IRQS - _IOW(VFIO_TYPE, VFIO_BASE + 10, struct vfio_irq_set)
*
* Set signaling, masking, and unmasking of interrupts. Caller provides
* struct vfio_irq_set with all fields set. 'start' and 'count' indicate
* the range of subindexes being specified.
*
* The DATA flags specify the type of data provided. If DATA_NONE, the
* operation performs the specified action immediately on the specified
* interrupt(s). For example, to unmask AUTOMASKED interrupt [0,0]:
* flags = (DATA_NONE|ACTION_UNMASK), index = 0, start = 0, count = 1.
*
* DATA_BOOL allows sparse support for the same on arrays of interrupts.
* For example, to mask interrupts [0,1] and [0,3] (but not [0,2]):
* flags = (DATA_BOOL|ACTION_MASK), index = 0, start = 1, count = 3,
* data = {1,0,1}
*
* DATA_EVENTFD binds the specified ACTION to the provided __s32 eventfd.
* A value of -1 can be used to either de-assign interrupts if already
* assigned or skip un-assigned interrupts. For example, to set an eventfd
* to be trigger for interrupts [0,0] and [0,2]:
* flags = (DATA_EVENTFD|ACTION_TRIGGER), index = 0, start = 0, count = 3,
* data = {fd1, -1, fd2}
* If index [0,1] is previously set, two count = 1 ioctls calls would be
* required to set [0,0] and [0,2] without changing [0,1].
*
* Once a signaling mechanism is set, DATA_BOOL or DATA_NONE can be used
* with ACTION_TRIGGER to perform kernel level interrupt loopback testing
* from userspace (ie. simulate hardware triggering).
*
* Setting of an event triggering mechanism to userspace for ACTION_TRIGGER
* enables the interrupt index for the device. Individual subindex interrupts
* can be disabled using the -1 value for DATA_EVENTFD or the index can be
* disabled as a whole with: flags = (DATA_NONE|ACTION_TRIGGER), count = 0.
*
* Note that ACTION_[UN]MASK specify user->kernel signaling (irqfds) while
* ACTION_TRIGGER specifies kernel->user signaling.
*/
struct vfio_irq_set {
__u32 argsz;
__u32 flags;
#define VFIO_IRQ_SET_DATA_NONE (1 << 0) /* Data not present */
#define VFIO_IRQ_SET_DATA_BOOL (1 << 1) /* Data is bool (u8) */
#define VFIO_IRQ_SET_DATA_EVENTFD (1 << 2) /* Data is eventfd (s32) */
#define VFIO_IRQ_SET_ACTION_MASK (1 << 3) /* Mask interrupt */
#define VFIO_IRQ_SET_ACTION_UNMASK (1 << 4) /* Unmask interrupt */
#define VFIO_IRQ_SET_ACTION_TRIGGER (1 << 5) /* Trigger interrupt */
__u32 index;
__u32 start;
__u32 count;
__u8 data[];
};
#define VFIO_DEVICE_SET_IRQS _IO(VFIO_TYPE, VFIO_BASE + 10)
#define VFIO_IRQ_SET_DATA_TYPE_MASK (VFIO_IRQ_SET_DATA_NONE | \
VFIO_IRQ_SET_DATA_BOOL | \
VFIO_IRQ_SET_DATA_EVENTFD)
#define VFIO_IRQ_SET_ACTION_TYPE_MASK (VFIO_IRQ_SET_ACTION_MASK | \
VFIO_IRQ_SET_ACTION_UNMASK | \
VFIO_IRQ_SET_ACTION_TRIGGER)
/**
* VFIO_DEVICE_RESET - _IO(VFIO_TYPE, VFIO_BASE + 11)
*
* Reset a device.
*/
#define VFIO_DEVICE_RESET _IO(VFIO_TYPE, VFIO_BASE + 11)
/*
* The VFIO-PCI bus driver makes use of the following fixed region and
* IRQ index mapping. Unimplemented regions return a size of zero.
* Unimplemented IRQ types return a count of zero.
*/
enum {
VFIO_PCI_BAR0_REGION_INDEX,
VFIO_PCI_BAR1_REGION_INDEX,
VFIO_PCI_BAR2_REGION_INDEX,
VFIO_PCI_BAR3_REGION_INDEX,
VFIO_PCI_BAR4_REGION_INDEX,
VFIO_PCI_BAR5_REGION_INDEX,
VFIO_PCI_ROM_REGION_INDEX,
VFIO_PCI_CONFIG_REGION_INDEX,
VFIO_PCI_NUM_REGIONS
};
enum {
VFIO_PCI_INTX_IRQ_INDEX,
VFIO_PCI_MSI_IRQ_INDEX,
VFIO_PCI_MSIX_IRQ_INDEX,
VFIO_PCI_NUM_IRQS
};
/* -------- 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 */