alistair23-linux/drivers/vfio/platform/vfio_platform_common.c
Thomas Gleixner 1802d0beec treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174
Based on 1 normalized pattern(s):

  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 this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 655 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070034.575739538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:41 -07:00

752 lines
17 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2013 - Virtual Open Systems
* Author: Antonios Motakis <a.motakis@virtualopensystems.com>
*/
#define dev_fmt(fmt) "VFIO: " fmt
#include <linux/device.h>
#include <linux/acpi.h>
#include <linux/iommu.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/uaccess.h>
#include <linux/vfio.h>
#include "vfio_platform_private.h"
#define DRIVER_VERSION "0.10"
#define DRIVER_AUTHOR "Antonios Motakis <a.motakis@virtualopensystems.com>"
#define DRIVER_DESC "VFIO platform base module"
#define VFIO_PLATFORM_IS_ACPI(vdev) ((vdev)->acpihid != NULL)
static LIST_HEAD(reset_list);
static DEFINE_MUTEX(driver_lock);
static vfio_platform_reset_fn_t vfio_platform_lookup_reset(const char *compat,
struct module **module)
{
struct vfio_platform_reset_node *iter;
vfio_platform_reset_fn_t reset_fn = NULL;
mutex_lock(&driver_lock);
list_for_each_entry(iter, &reset_list, link) {
if (!strcmp(iter->compat, compat) &&
try_module_get(iter->owner)) {
*module = iter->owner;
reset_fn = iter->of_reset;
break;
}
}
mutex_unlock(&driver_lock);
return reset_fn;
}
static int vfio_platform_acpi_probe(struct vfio_platform_device *vdev,
struct device *dev)
{
struct acpi_device *adev;
if (acpi_disabled)
return -ENOENT;
adev = ACPI_COMPANION(dev);
if (!adev) {
dev_err(dev, "ACPI companion device not found for %s\n",
vdev->name);
return -ENODEV;
}
#ifdef CONFIG_ACPI
vdev->acpihid = acpi_device_hid(adev);
#endif
return WARN_ON(!vdev->acpihid) ? -EINVAL : 0;
}
static int vfio_platform_acpi_call_reset(struct vfio_platform_device *vdev,
const char **extra_dbg)
{
#ifdef CONFIG_ACPI
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
struct device *dev = vdev->device;
acpi_handle handle = ACPI_HANDLE(dev);
acpi_status acpi_ret;
acpi_ret = acpi_evaluate_object(handle, "_RST", NULL, &buffer);
if (ACPI_FAILURE(acpi_ret)) {
if (extra_dbg)
*extra_dbg = acpi_format_exception(acpi_ret);
return -EINVAL;
}
return 0;
#else
return -ENOENT;
#endif
}
static bool vfio_platform_acpi_has_reset(struct vfio_platform_device *vdev)
{
#ifdef CONFIG_ACPI
struct device *dev = vdev->device;
acpi_handle handle = ACPI_HANDLE(dev);
return acpi_has_method(handle, "_RST");
#else
return false;
#endif
}
static bool vfio_platform_has_reset(struct vfio_platform_device *vdev)
{
if (VFIO_PLATFORM_IS_ACPI(vdev))
return vfio_platform_acpi_has_reset(vdev);
return vdev->of_reset ? true : false;
}
static int vfio_platform_get_reset(struct vfio_platform_device *vdev)
{
if (VFIO_PLATFORM_IS_ACPI(vdev))
return vfio_platform_acpi_has_reset(vdev) ? 0 : -ENOENT;
vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
&vdev->reset_module);
if (!vdev->of_reset) {
request_module("vfio-reset:%s", vdev->compat);
vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
&vdev->reset_module);
}
return vdev->of_reset ? 0 : -ENOENT;
}
static void vfio_platform_put_reset(struct vfio_platform_device *vdev)
{
if (VFIO_PLATFORM_IS_ACPI(vdev))
return;
if (vdev->of_reset)
module_put(vdev->reset_module);
}
static int vfio_platform_regions_init(struct vfio_platform_device *vdev)
{
int cnt = 0, i;
while (vdev->get_resource(vdev, cnt))
cnt++;
vdev->regions = kcalloc(cnt, sizeof(struct vfio_platform_region),
GFP_KERNEL);
if (!vdev->regions)
return -ENOMEM;
for (i = 0; i < cnt; i++) {
struct resource *res =
vdev->get_resource(vdev, i);
if (!res)
goto err;
vdev->regions[i].addr = res->start;
vdev->regions[i].size = resource_size(res);
vdev->regions[i].flags = 0;
switch (resource_type(res)) {
case IORESOURCE_MEM:
vdev->regions[i].type = VFIO_PLATFORM_REGION_TYPE_MMIO;
vdev->regions[i].flags |= VFIO_REGION_INFO_FLAG_READ;
if (!(res->flags & IORESOURCE_READONLY))
vdev->regions[i].flags |=
VFIO_REGION_INFO_FLAG_WRITE;
/*
* Only regions addressed with PAGE granularity may be
* MMAPed securely.
*/
if (!(vdev->regions[i].addr & ~PAGE_MASK) &&
!(vdev->regions[i].size & ~PAGE_MASK))
vdev->regions[i].flags |=
VFIO_REGION_INFO_FLAG_MMAP;
break;
case IORESOURCE_IO:
vdev->regions[i].type = VFIO_PLATFORM_REGION_TYPE_PIO;
break;
default:
goto err;
}
}
vdev->num_regions = cnt;
return 0;
err:
kfree(vdev->regions);
return -EINVAL;
}
static void vfio_platform_regions_cleanup(struct vfio_platform_device *vdev)
{
int i;
for (i = 0; i < vdev->num_regions; i++)
iounmap(vdev->regions[i].ioaddr);
vdev->num_regions = 0;
kfree(vdev->regions);
}
static int vfio_platform_call_reset(struct vfio_platform_device *vdev,
const char **extra_dbg)
{
if (VFIO_PLATFORM_IS_ACPI(vdev)) {
dev_info(vdev->device, "reset\n");
return vfio_platform_acpi_call_reset(vdev, extra_dbg);
} else if (vdev->of_reset) {
dev_info(vdev->device, "reset\n");
return vdev->of_reset(vdev);
}
dev_warn(vdev->device, "no reset function found!\n");
return -EINVAL;
}
static void vfio_platform_release(void *device_data)
{
struct vfio_platform_device *vdev = device_data;
mutex_lock(&driver_lock);
if (!(--vdev->refcnt)) {
const char *extra_dbg = NULL;
int ret;
ret = vfio_platform_call_reset(vdev, &extra_dbg);
if (ret && vdev->reset_required) {
dev_warn(vdev->device, "reset driver is required and reset call failed in release (%d) %s\n",
ret, extra_dbg ? extra_dbg : "");
WARN_ON(1);
}
pm_runtime_put(vdev->device);
vfio_platform_regions_cleanup(vdev);
vfio_platform_irq_cleanup(vdev);
}
mutex_unlock(&driver_lock);
module_put(vdev->parent_module);
}
static int vfio_platform_open(void *device_data)
{
struct vfio_platform_device *vdev = device_data;
int ret;
if (!try_module_get(vdev->parent_module))
return -ENODEV;
mutex_lock(&driver_lock);
if (!vdev->refcnt) {
const char *extra_dbg = NULL;
ret = vfio_platform_regions_init(vdev);
if (ret)
goto err_reg;
ret = vfio_platform_irq_init(vdev);
if (ret)
goto err_irq;
ret = pm_runtime_get_sync(vdev->device);
if (ret < 0)
goto err_pm;
ret = vfio_platform_call_reset(vdev, &extra_dbg);
if (ret && vdev->reset_required) {
dev_warn(vdev->device, "reset driver is required and reset call failed in open (%d) %s\n",
ret, extra_dbg ? extra_dbg : "");
goto err_rst;
}
}
vdev->refcnt++;
mutex_unlock(&driver_lock);
return 0;
err_rst:
pm_runtime_put(vdev->device);
err_pm:
vfio_platform_irq_cleanup(vdev);
err_irq:
vfio_platform_regions_cleanup(vdev);
err_reg:
mutex_unlock(&driver_lock);
module_put(THIS_MODULE);
return ret;
}
static long vfio_platform_ioctl(void *device_data,
unsigned int cmd, unsigned long arg)
{
struct vfio_platform_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;
if (vfio_platform_has_reset(vdev))
vdev->flags |= VFIO_DEVICE_FLAGS_RESET;
info.flags = vdev->flags;
info.num_regions = vdev->num_regions;
info.num_irqs = vdev->num_irqs;
return copy_to_user((void __user *)arg, &info, minsz) ?
-EFAULT : 0;
} else if (cmd == VFIO_DEVICE_GET_REGION_INFO) {
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;
if (info.index >= vdev->num_regions)
return -EINVAL;
/* map offset to the physical address */
info.offset = VFIO_PLATFORM_INDEX_TO_OFFSET(info.index);
info.size = vdev->regions[info.index].size;
info.flags = vdev->regions[info.index].flags;
return copy_to_user((void __user *)arg, &info, minsz) ?
-EFAULT : 0;
} 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)
return -EINVAL;
if (info.index >= vdev->num_irqs)
return -EINVAL;
info.flags = vdev->irqs[info.index].flags;
info.count = vdev->irqs[info.index].count;
return copy_to_user((void __user *)arg, &info, minsz) ?
-EFAULT : 0;
} else if (cmd == VFIO_DEVICE_SET_IRQS) {
struct vfio_irq_set hdr;
u8 *data = NULL;
int ret = 0;
size_t data_size = 0;
minsz = offsetofend(struct vfio_irq_set, count);
if (copy_from_user(&hdr, (void __user *)arg, minsz))
return -EFAULT;
ret = vfio_set_irqs_validate_and_prepare(&hdr, vdev->num_irqs,
vdev->num_irqs, &data_size);
if (ret)
return ret;
if (data_size) {
data = memdup_user((void __user *)(arg + minsz),
data_size);
if (IS_ERR(data))
return PTR_ERR(data);
}
mutex_lock(&vdev->igate);
ret = vfio_platform_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 vfio_platform_call_reset(vdev, NULL);
}
return -ENOTTY;
}
static ssize_t vfio_platform_read_mmio(struct vfio_platform_region *reg,
char __user *buf, size_t count,
loff_t off)
{
unsigned int done = 0;
if (!reg->ioaddr) {
reg->ioaddr =
ioremap_nocache(reg->addr, reg->size);
if (!reg->ioaddr)
return -ENOMEM;
}
while (count) {
size_t filled;
if (count >= 4 && !(off % 4)) {
u32 val;
val = ioread32(reg->ioaddr + off);
if (copy_to_user(buf, &val, 4))
goto err;
filled = 4;
} else if (count >= 2 && !(off % 2)) {
u16 val;
val = ioread16(reg->ioaddr + off);
if (copy_to_user(buf, &val, 2))
goto err;
filled = 2;
} else {
u8 val;
val = ioread8(reg->ioaddr + off);
if (copy_to_user(buf, &val, 1))
goto err;
filled = 1;
}
count -= filled;
done += filled;
off += filled;
buf += filled;
}
return done;
err:
return -EFAULT;
}
static ssize_t vfio_platform_read(void *device_data, char __user *buf,
size_t count, loff_t *ppos)
{
struct vfio_platform_device *vdev = device_data;
unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
if (index >= vdev->num_regions)
return -EINVAL;
if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ))
return -EINVAL;
if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
return vfio_platform_read_mmio(&vdev->regions[index],
buf, count, off);
else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
return -EINVAL; /* not implemented */
return -EINVAL;
}
static ssize_t vfio_platform_write_mmio(struct vfio_platform_region *reg,
const char __user *buf, size_t count,
loff_t off)
{
unsigned int done = 0;
if (!reg->ioaddr) {
reg->ioaddr =
ioremap_nocache(reg->addr, reg->size);
if (!reg->ioaddr)
return -ENOMEM;
}
while (count) {
size_t filled;
if (count >= 4 && !(off % 4)) {
u32 val;
if (copy_from_user(&val, buf, 4))
goto err;
iowrite32(val, reg->ioaddr + off);
filled = 4;
} else if (count >= 2 && !(off % 2)) {
u16 val;
if (copy_from_user(&val, buf, 2))
goto err;
iowrite16(val, reg->ioaddr + off);
filled = 2;
} else {
u8 val;
if (copy_from_user(&val, buf, 1))
goto err;
iowrite8(val, reg->ioaddr + off);
filled = 1;
}
count -= filled;
done += filled;
off += filled;
buf += filled;
}
return done;
err:
return -EFAULT;
}
static ssize_t vfio_platform_write(void *device_data, const char __user *buf,
size_t count, loff_t *ppos)
{
struct vfio_platform_device *vdev = device_data;
unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
if (index >= vdev->num_regions)
return -EINVAL;
if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE))
return -EINVAL;
if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
return vfio_platform_write_mmio(&vdev->regions[index],
buf, count, off);
else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
return -EINVAL; /* not implemented */
return -EINVAL;
}
static int vfio_platform_mmap_mmio(struct vfio_platform_region region,
struct vm_area_struct *vma)
{
u64 req_len, pgoff, req_start;
req_len = vma->vm_end - vma->vm_start;
pgoff = vma->vm_pgoff &
((1U << (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
req_start = pgoff << PAGE_SHIFT;
if (region.size < PAGE_SIZE || req_start + req_len > region.size)
return -EINVAL;
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
vma->vm_pgoff = (region.addr >> PAGE_SHIFT) + pgoff;
return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
req_len, vma->vm_page_prot);
}
static int vfio_platform_mmap(void *device_data, struct vm_area_struct *vma)
{
struct vfio_platform_device *vdev = device_data;
unsigned int index;
index = vma->vm_pgoff >> (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT);
if (vma->vm_end < vma->vm_start)
return -EINVAL;
if (!(vma->vm_flags & VM_SHARED))
return -EINVAL;
if (index >= vdev->num_regions)
return -EINVAL;
if (vma->vm_start & ~PAGE_MASK)
return -EINVAL;
if (vma->vm_end & ~PAGE_MASK)
return -EINVAL;
if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_MMAP))
return -EINVAL;
if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ)
&& (vma->vm_flags & VM_READ))
return -EINVAL;
if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE)
&& (vma->vm_flags & VM_WRITE))
return -EINVAL;
vma->vm_private_data = vdev;
if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
return vfio_platform_mmap_mmio(vdev->regions[index], vma);
else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
return -EINVAL; /* not implemented */
return -EINVAL;
}
static const struct vfio_device_ops vfio_platform_ops = {
.name = "vfio-platform",
.open = vfio_platform_open,
.release = vfio_platform_release,
.ioctl = vfio_platform_ioctl,
.read = vfio_platform_read,
.write = vfio_platform_write,
.mmap = vfio_platform_mmap,
};
static int vfio_platform_of_probe(struct vfio_platform_device *vdev,
struct device *dev)
{
int ret;
ret = device_property_read_string(dev, "compatible",
&vdev->compat);
if (ret)
dev_err(dev, "Cannot retrieve compat for %s\n", vdev->name);
return ret;
}
/*
* There can be two kernel build combinations. One build where
* ACPI is not selected in Kconfig and another one with the ACPI Kconfig.
*
* In the first case, vfio_platform_acpi_probe will return since
* acpi_disabled is 1. DT user will not see any kind of messages from
* ACPI.
*
* In the second case, both DT and ACPI is compiled in but the system is
* booting with any of these combinations.
*
* If the firmware is DT type, then acpi_disabled is 1. The ACPI probe routine
* terminates immediately without any messages.
*
* If the firmware is ACPI type, then acpi_disabled is 0. All other checks are
* valid checks. We cannot claim that this system is DT.
*/
int vfio_platform_probe_common(struct vfio_platform_device *vdev,
struct device *dev)
{
struct iommu_group *group;
int ret;
if (!vdev)
return -EINVAL;
ret = vfio_platform_acpi_probe(vdev, dev);
if (ret)
ret = vfio_platform_of_probe(vdev, dev);
if (ret)
return ret;
vdev->device = dev;
ret = vfio_platform_get_reset(vdev);
if (ret && vdev->reset_required) {
dev_err(dev, "No reset function found for device %s\n",
vdev->name);
return ret;
}
group = vfio_iommu_group_get(dev);
if (!group) {
dev_err(dev, "No IOMMU group for device %s\n", vdev->name);
ret = -EINVAL;
goto put_reset;
}
ret = vfio_add_group_dev(dev, &vfio_platform_ops, vdev);
if (ret)
goto put_iommu;
mutex_init(&vdev->igate);
pm_runtime_enable(vdev->device);
return 0;
put_iommu:
vfio_iommu_group_put(group, dev);
put_reset:
vfio_platform_put_reset(vdev);
return ret;
}
EXPORT_SYMBOL_GPL(vfio_platform_probe_common);
struct vfio_platform_device *vfio_platform_remove_common(struct device *dev)
{
struct vfio_platform_device *vdev;
vdev = vfio_del_group_dev(dev);
if (vdev) {
pm_runtime_disable(vdev->device);
vfio_platform_put_reset(vdev);
vfio_iommu_group_put(dev->iommu_group, dev);
}
return vdev;
}
EXPORT_SYMBOL_GPL(vfio_platform_remove_common);
void __vfio_platform_register_reset(struct vfio_platform_reset_node *node)
{
mutex_lock(&driver_lock);
list_add(&node->link, &reset_list);
mutex_unlock(&driver_lock);
}
EXPORT_SYMBOL_GPL(__vfio_platform_register_reset);
void vfio_platform_unregister_reset(const char *compat,
vfio_platform_reset_fn_t fn)
{
struct vfio_platform_reset_node *iter, *temp;
mutex_lock(&driver_lock);
list_for_each_entry_safe(iter, temp, &reset_list, link) {
if (!strcmp(iter->compat, compat) && (iter->of_reset == fn)) {
list_del(&iter->link);
break;
}
}
mutex_unlock(&driver_lock);
}
EXPORT_SYMBOL_GPL(vfio_platform_unregister_reset);
MODULE_VERSION(DRIVER_VERSION);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);