mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
88 lines
2.1 KiB
88 lines
2.1 KiB
// SPDX-License-Identifier: GPL-2.0 |
|
/* |
|
* Async I/O region for vfio_ccw |
|
* |
|
* Copyright Red Hat, Inc. 2019 |
|
* |
|
* Author(s): Cornelia Huck <[email protected]> |
|
*/ |
|
|
|
#include <linux/vfio.h> |
|
#include <linux/mdev.h> |
|
|
|
#include "vfio_ccw_private.h" |
|
|
|
static ssize_t vfio_ccw_async_region_read(struct vfio_ccw_private *private, |
|
char __user *buf, size_t count, |
|
loff_t *ppos) |
|
{ |
|
unsigned int i = VFIO_CCW_OFFSET_TO_INDEX(*ppos) - VFIO_CCW_NUM_REGIONS; |
|
loff_t pos = *ppos & VFIO_CCW_OFFSET_MASK; |
|
struct ccw_cmd_region *region; |
|
int ret; |
|
|
|
if (pos + count > sizeof(*region)) |
|
return -EINVAL; |
|
|
|
mutex_lock(&private->io_mutex); |
|
region = private->region[i].data; |
|
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_async_region_write(struct vfio_ccw_private *private, |
|
const char __user *buf, size_t count, |
|
loff_t *ppos) |
|
{ |
|
unsigned int i = VFIO_CCW_OFFSET_TO_INDEX(*ppos) - VFIO_CCW_NUM_REGIONS; |
|
loff_t pos = *ppos & VFIO_CCW_OFFSET_MASK; |
|
struct ccw_cmd_region *region; |
|
int ret; |
|
|
|
if (pos + count > sizeof(*region)) |
|
return -EINVAL; |
|
|
|
if (!mutex_trylock(&private->io_mutex)) |
|
return -EAGAIN; |
|
|
|
region = private->region[i].data; |
|
if (copy_from_user((void *)region + pos, buf, count)) { |
|
ret = -EFAULT; |
|
goto out_unlock; |
|
} |
|
|
|
vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_ASYNC_REQ); |
|
|
|
ret = region->ret_code ? region->ret_code : count; |
|
|
|
out_unlock: |
|
mutex_unlock(&private->io_mutex); |
|
return ret; |
|
} |
|
|
|
static void vfio_ccw_async_region_release(struct vfio_ccw_private *private, |
|
struct vfio_ccw_region *region) |
|
{ |
|
|
|
} |
|
|
|
static const struct vfio_ccw_regops vfio_ccw_async_region_ops = { |
|
.read = vfio_ccw_async_region_read, |
|
.write = vfio_ccw_async_region_write, |
|
.release = vfio_ccw_async_region_release, |
|
}; |
|
|
|
int vfio_ccw_register_async_dev_regions(struct vfio_ccw_private *private) |
|
{ |
|
return vfio_ccw_register_dev_region(private, |
|
VFIO_REGION_SUBTYPE_CCW_ASYNC_CMD, |
|
&vfio_ccw_async_region_ops, |
|
sizeof(struct ccw_cmd_region), |
|
VFIO_REGION_INFO_FLAG_READ | |
|
VFIO_REGION_INFO_FLAG_WRITE, |
|
private->cmd_region); |
|
}
|
|
|