linux/drivers/s390/cio/vfio_ccw_ops.c

598 lines
14 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Physical device callbacks for vfio_ccw
*
* Copyright IBM Corp. 2017
* Copyright Red Hat, Inc. 2019
*
* Author(s): Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
* Xiao Feng Ren <renxiaof@linux.vnet.ibm.com>
* Cornelia Huck <cohuck@redhat.com>
*/
#include <linux/vfio.h>
#include <linux/mdev.h>
#include <linux/nospec.h>
#include <linux/slab.h>
#include "vfio_ccw_private.h"
static int vfio_ccw_mdev_reset(struct mdev_device *mdev)
{
struct vfio_ccw_private *private;
struct subchannel *sch;
int ret;
private = dev_get_drvdata(mdev_parent_dev(mdev));
sch = private->sch;
/*
* TODO:
* In the cureent stage, some things like "no I/O running" and "no
* interrupt pending" are clear, but we are not sure what other state
* we need to care about.
* There are still a lot more instructions need to be handled. We
* should come back here later.
*/
ret = vfio_ccw_sch_quiesce(sch);
if (ret)
return ret;
ret = cio_enable_subchannel(sch, (u32)(unsigned long)sch);
if (!ret)
private->state = VFIO_CCW_STATE_IDLE;
return ret;
}
static int vfio_ccw_mdev_notifier(struct notifier_block *nb,
unsigned long action,
void *data)
{
struct vfio_ccw_private *private =
container_of(nb, struct vfio_ccw_private, nb);
/*
* Vendor drivers MUST unpin pages in response to an
* invalidation.
*/
if (action == VFIO_IOMMU_NOTIFY_DMA_UNMAP) {
struct vfio_iommu_type1_dma_unmap *unmap = data;
if (!cp_iova_pinned(&private->cp, unmap->iova))
return NOTIFY_OK;
if (vfio_ccw_mdev_reset(private->mdev))
return NOTIFY_BAD;
cp_free(&private->cp);
return NOTIFY_OK;
}
return NOTIFY_DONE;
}
static ssize_t name_show(struct kobject *kobj, struct device *dev, char *buf)
{
return sprintf(buf, "I/O subchannel (Non-QDIO)\n");
}
static MDEV_TYPE_ATTR_RO(name);
static ssize_t device_api_show(struct kobject *kobj, struct device *dev,
char *buf)
{
return sprintf(buf, "%s\n", VFIO_DEVICE_API_CCW_STRING);
}
static MDEV_TYPE_ATTR_RO(device_api);
static ssize_t available_instances_show(struct kobject *kobj,
struct device *dev, char *buf)
{
struct vfio_ccw_private *private = dev_get_drvdata(dev);
return sprintf(buf, "%d\n", atomic_read(&private->avail));
}
static MDEV_TYPE_ATTR_RO(available_instances);
static struct attribute *mdev_types_attrs[] = {
&mdev_type_attr_name.attr,
&mdev_type_attr_device_api.attr,
&mdev_type_attr_available_instances.attr,
NULL,
};
static struct attribute_group mdev_type_group = {
.name = "io",
.attrs = mdev_types_attrs,
};
static struct attribute_group *mdev_type_groups[] = {
&mdev_type_group,
NULL,
};
static int vfio_ccw_mdev_create(struct kobject *kobj, struct mdev_device *mdev)
{
struct vfio_ccw_private *private =
dev_get_drvdata(mdev_parent_dev(mdev));
if (private->state == VFIO_CCW_STATE_NOT_OPER)
return -ENODEV;
if (atomic_dec_if_positive(&private->avail) < 0)
return -EPERM;
private->mdev = mdev;
private->state = VFIO_CCW_STATE_IDLE;
VFIO_CCW_MSG_EVENT(2, "mdev %pUl, sch %x.%x.%04x: create\n",
mdev_uuid(mdev), private->sch->schid.cssid,
private->sch->schid.ssid,
private->sch->schid.sch_no);
return 0;
}
static int vfio_ccw_mdev_remove(struct mdev_device *mdev)
{
struct vfio_ccw_private *private =
dev_get_drvdata(mdev_parent_dev(mdev));
VFIO_CCW_MSG_EVENT(2, "mdev %pUl, sch %x.%x.%04x: remove\n",
mdev_uuid(mdev), private->sch->schid.cssid,
private->sch->schid.ssid,
private->sch->schid.sch_no);
if ((private->state != VFIO_CCW_STATE_NOT_OPER) &&
(private->state != VFIO_CCW_STATE_STANDBY)) {
if (!vfio_ccw_sch_quiesce(private->sch))
private->state = VFIO_CCW_STATE_STANDBY;
/* The state will be NOT_OPER on error. */
}
cp_free(&private->cp);
private->mdev = NULL;
atomic_inc(&private->avail);
return 0;
}
static int vfio_ccw_mdev_open(struct mdev_device *mdev)
{
struct vfio_ccw_private *private =
dev_get_drvdata(mdev_parent_dev(mdev));
unsigned long events = VFIO_IOMMU_NOTIFY_DMA_UNMAP;
int ret;
private->nb.notifier_call = vfio_ccw_mdev_notifier;
ret = vfio_register_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY,
&events, &private->nb);
if (ret)
return ret;
ret = vfio_ccw_register_async_dev_regions(private);
if (ret)
vfio_unregister_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY,
&private->nb);
return ret;
}
static void vfio_ccw_mdev_release(struct mdev_device *mdev)
{
struct vfio_ccw_private *private =
dev_get_drvdata(mdev_parent_dev(mdev));
int i;
if ((private->state != VFIO_CCW_STATE_NOT_OPER) &&
(private->state != VFIO_CCW_STATE_STANDBY)) {
if (!vfio_ccw_mdev_reset(mdev))
private->state = VFIO_CCW_STATE_STANDBY;
/* The state will be NOT_OPER on error. */
}
cp_free(&private->cp);
vfio_unregister_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY,
&private->nb);
for (i = 0; i < private->num_regions; i++)
private->region[i].ops->release(private, &private->region[i]);
private->num_regions = 0;
kfree(private->region);
private->region = NULL;
}
static ssize_t vfio_ccw_mdev_read_io_region(struct vfio_ccw_private *private,
char __user *buf, size_t count,
loff_t *ppos)
{
loff_t pos = *ppos & VFIO_CCW_OFFSET_MASK;
struct ccw_io_region *region;
int ret;
if (pos + count > sizeof(*region))
return -EINVAL;
mutex_lock(&private->io_mutex);
region = private->io_region;
if (copy_to_user(buf, (void *)region + pos, count))
ret = -EFAULT;
else
ret = count;
mutex_unlock(&private->io_mutex);
return ret;
}
static ssize_t vfio_ccw_mdev_read(struct mdev_device *mdev,
char __user *buf,
size_t count,
loff_t *ppos)
{
unsigned int index = VFIO_CCW_OFFSET_TO_INDEX(*ppos);
struct vfio_ccw_private *private;
private = dev_get_drvdata(mdev_parent_dev(mdev));
if (index >= VFIO_CCW_NUM_REGIONS + private->num_regions)
return -EINVAL;
switch (index) {
case VFIO_CCW_CONFIG_REGION_INDEX:
return vfio_ccw_mdev_read_io_region(private, buf, count, ppos);
default:
index -= VFIO_CCW_NUM_REGIONS;
return private->region[index].ops->read(private, buf, count,
ppos);
}
return -EINVAL;
}
static ssize_t vfio_ccw_mdev_write_io_region(struct vfio_ccw_private *private,
const char __user *buf,
size_t count, loff_t *ppos)
{
loff_t pos = *ppos & VFIO_CCW_OFFSET_MASK;
struct ccw_io_region *region;
int ret;
if (pos + count > sizeof(*region))
return -EINVAL;
if (!mutex_trylock(&private->io_mutex))
return -EAGAIN;
region = private->io_region;
if (copy_from_user((void *)region + pos, buf, count)) {
ret = -EFAULT;
goto out_unlock;
}
vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_IO_REQ);
if (region->ret_code != 0)
private->state = VFIO_CCW_STATE_IDLE;
ret = (region->ret_code != 0) ? region->ret_code : count;
out_unlock:
mutex_unlock(&private->io_mutex);
return ret;
}
static ssize_t vfio_ccw_mdev_write(struct mdev_device *mdev,
const char __user *buf,
size_t count,
loff_t *ppos)
{
unsigned int index = VFIO_CCW_OFFSET_TO_INDEX(*ppos);
struct vfio_ccw_private *private;
private = dev_get_drvdata(mdev_parent_dev(mdev));
if (index >= VFIO_CCW_NUM_REGIONS + private->num_regions)
return -EINVAL;
switch (index) {
case VFIO_CCW_CONFIG_REGION_INDEX:
return vfio_ccw_mdev_write_io_region(private, buf, count, ppos);
default:
index -= VFIO_CCW_NUM_REGIONS;
return private->region[index].ops->write(private, buf, count,
ppos);
}
return -EINVAL;
}
static int vfio_ccw_mdev_get_device_info(struct vfio_device_info *info,
struct mdev_device *mdev)
{
struct vfio_ccw_private *private;
private = dev_get_drvdata(mdev_parent_dev(mdev));
info->flags = VFIO_DEVICE_FLAGS_CCW | VFIO_DEVICE_FLAGS_RESET;
info->num_regions = VFIO_CCW_NUM_REGIONS + private->num_regions;
info->num_irqs = VFIO_CCW_NUM_IRQS;
return 0;
}
static int vfio_ccw_mdev_get_region_info(struct vfio_region_info *info,
struct mdev_device *mdev,
unsigned long arg)
{
struct vfio_ccw_private *private;
int i;
private = dev_get_drvdata(mdev_parent_dev(mdev));
switch (info->index) {
case VFIO_CCW_CONFIG_REGION_INDEX:
info->offset = 0;
info->size = sizeof(struct ccw_io_region);
info->flags = VFIO_REGION_INFO_FLAG_READ
| VFIO_REGION_INFO_FLAG_WRITE;
return 0;
default: /* all other regions are handled via capability chain */
{
struct vfio_info_cap caps = { .buf = NULL, .size = 0 };
struct vfio_region_info_cap_type cap_type = {
.header.id = VFIO_REGION_INFO_CAP_TYPE,
.header.version = 1 };
int ret;
if (info->index >=
VFIO_CCW_NUM_REGIONS + private->num_regions)
return -EINVAL;
info->index = array_index_nospec(info->index,
VFIO_CCW_NUM_REGIONS +
private->num_regions);
i = info->index - VFIO_CCW_NUM_REGIONS;
info->offset = VFIO_CCW_INDEX_TO_OFFSET(info->index);
info->size = private->region[i].size;
info->flags = private->region[i].flags;
cap_type.type = private->region[i].type;
cap_type.subtype = private->region[i].subtype;
ret = vfio_info_add_capability(&caps, &cap_type.header,
sizeof(cap_type));
if (ret)
return ret;
info->flags |= VFIO_REGION_INFO_FLAG_CAPS;
if (info->argsz < sizeof(*info) + caps.size) {
info->argsz = sizeof(*info) + caps.size;
info->cap_offset = 0;
} else {
vfio_info_cap_shift(&caps, sizeof(*info));
if (copy_to_user((void __user *)arg + sizeof(*info),
caps.buf, caps.size)) {
kfree(caps.buf);
return -EFAULT;
}
info->cap_offset = sizeof(*info);
}
kfree(caps.buf);
}
}
return 0;
}
static int vfio_ccw_mdev_get_irq_info(struct vfio_irq_info *info)
{
if (info->index != VFIO_CCW_IO_IRQ_INDEX)
return -EINVAL;
info->count = 1;
info->flags = VFIO_IRQ_INFO_EVENTFD;
return 0;
}
static int vfio_ccw_mdev_set_irqs(struct mdev_device *mdev,
uint32_t flags,
void __user *data)
{
struct vfio_ccw_private *private;
struct eventfd_ctx **ctx;
if (!(flags & VFIO_IRQ_SET_ACTION_TRIGGER))
return -EINVAL;
private = dev_get_drvdata(mdev_parent_dev(mdev));
ctx = &private->io_trigger;
switch (flags & VFIO_IRQ_SET_DATA_TYPE_MASK) {
case VFIO_IRQ_SET_DATA_NONE:
{
if (*ctx)
eventfd_signal(*ctx, 1);
return 0;
}
case VFIO_IRQ_SET_DATA_BOOL:
{
uint8_t trigger;
if (get_user(trigger, (uint8_t __user *)data))
return -EFAULT;
if (trigger && *ctx)
eventfd_signal(*ctx, 1);
return 0;
}
case VFIO_IRQ_SET_DATA_EVENTFD:
{
int32_t fd;
if (get_user(fd, (int32_t __user *)data))
return -EFAULT;
if (fd == -1) {
if (*ctx)
eventfd_ctx_put(*ctx);
*ctx = NULL;
} else if (fd >= 0) {
struct eventfd_ctx *efdctx;
efdctx = eventfd_ctx_fdget(fd);
if (IS_ERR(efdctx))
return PTR_ERR(efdctx);
if (*ctx)
eventfd_ctx_put(*ctx);
*ctx = efdctx;
} else
return -EINVAL;
return 0;
}
default:
return -EINVAL;
}
}
int vfio_ccw_register_dev_region(struct vfio_ccw_private *private,
unsigned int subtype,
const struct vfio_ccw_regops *ops,
size_t size, u32 flags, void *data)
{
struct vfio_ccw_region *region;
region = krealloc(private->region,
(private->num_regions + 1) * sizeof(*region),
GFP_KERNEL);
if (!region)
return -ENOMEM;
private->region = region;
private->region[private->num_regions].type = VFIO_REGION_TYPE_CCW;
private->region[private->num_regions].subtype = subtype;
private->region[private->num_regions].ops = ops;
private->region[private->num_regions].size = size;
private->region[private->num_regions].flags = flags;
private->region[private->num_regions].data = data;
private->num_regions++;
return 0;
}
static ssize_t vfio_ccw_mdev_ioctl(struct mdev_device *mdev,
unsigned int cmd,
unsigned long arg)
{
int ret = 0;
unsigned long minsz;
switch (cmd) {
case 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;
ret = vfio_ccw_mdev_get_device_info(&info, mdev);
if (ret)
return ret;
return copy_to_user((void __user *)arg, &info, minsz);
}
case 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;
ret = vfio_ccw_mdev_get_region_info(&info, mdev, arg);
if (ret)
return ret;
return copy_to_user((void __user *)arg, &info, minsz);
}
case 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_CCW_NUM_IRQS)
return -EINVAL;
ret = vfio_ccw_mdev_get_irq_info(&info);
if (ret)
return ret;
if (info.count == -1)
return -EINVAL;
return copy_to_user((void __user *)arg, &info, minsz);
}
case VFIO_DEVICE_SET_IRQS:
{
struct vfio_irq_set hdr;
size_t data_size;
void __user *data;
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, 1,
VFIO_CCW_NUM_IRQS,
&data_size);
if (ret)
return ret;
data = (void __user *)(arg + minsz);
return vfio_ccw_mdev_set_irqs(mdev, hdr.flags, data);
}
case VFIO_DEVICE_RESET:
return vfio_ccw_mdev_reset(mdev);
default:
return -ENOTTY;
}
}
static const struct mdev_parent_ops vfio_ccw_mdev_ops = {
.owner = THIS_MODULE,
.supported_type_groups = mdev_type_groups,
.create = vfio_ccw_mdev_create,
.remove = vfio_ccw_mdev_remove,
.open = vfio_ccw_mdev_open,
.release = vfio_ccw_mdev_release,
.read = vfio_ccw_mdev_read,
.write = vfio_ccw_mdev_write,
.ioctl = vfio_ccw_mdev_ioctl,
};
int vfio_ccw_mdev_reg(struct subchannel *sch)
{
return mdev_register_device(&sch->dev, &vfio_ccw_mdev_ops);
}
void vfio_ccw_mdev_unreg(struct subchannel *sch)
{
mdev_unregister_device(&sch->dev);
}