swh:1:snp:49cd9498d6cccc5e78252c27dcb645bcf7bf0c91
Tip revision: ba47d845d715a010f7b51f6f89bae32845e6acb7 authored by Linus Torvalds on 19 July 2020, 22:41:18 UTC
Linux 5.8-rc6
Linux 5.8-rc6
Tip revision: ba47d84
hid-hyperv.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2009, Citrix Systems, Inc.
* Copyright (c) 2010, Microsoft Corporation.
* Copyright (c) 2011, Novell Inc.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/completion.h>
#include <linux/input.h>
#include <linux/hid.h>
#include <linux/hiddev.h>
#include <linux/hyperv.h>
struct hv_input_dev_info {
unsigned int size;
unsigned short vendor;
unsigned short product;
unsigned short version;
unsigned short reserved[11];
};
/* The maximum size of a synthetic input message. */
#define SYNTHHID_MAX_INPUT_REPORT_SIZE 16
/*
* Current version
*
* History:
* Beta, RC < 2008/1/22 1,0
* RC > 2008/1/22 2,0
*/
#define SYNTHHID_INPUT_VERSION_MAJOR 2
#define SYNTHHID_INPUT_VERSION_MINOR 0
#define SYNTHHID_INPUT_VERSION (SYNTHHID_INPUT_VERSION_MINOR | \
(SYNTHHID_INPUT_VERSION_MAJOR << 16))
#pragma pack(push, 1)
/*
* Message types in the synthetic input protocol
*/
enum synthhid_msg_type {
SYNTH_HID_PROTOCOL_REQUEST,
SYNTH_HID_PROTOCOL_RESPONSE,
SYNTH_HID_INITIAL_DEVICE_INFO,
SYNTH_HID_INITIAL_DEVICE_INFO_ACK,
SYNTH_HID_INPUT_REPORT,
SYNTH_HID_MAX
};
/*
* Basic message structures.
*/
struct synthhid_msg_hdr {
enum synthhid_msg_type type;
u32 size;
};
struct synthhid_msg {
struct synthhid_msg_hdr header;
char data[1]; /* Enclosed message */
};
union synthhid_version {
struct {
u16 minor_version;
u16 major_version;
};
u32 version;
};
/*
* Protocol messages
*/
struct synthhid_protocol_request {
struct synthhid_msg_hdr header;
union synthhid_version version_requested;
};
struct synthhid_protocol_response {
struct synthhid_msg_hdr header;
union synthhid_version version_requested;
unsigned char approved;
};
struct synthhid_device_info {
struct synthhid_msg_hdr header;
struct hv_input_dev_info hid_dev_info;
struct hid_descriptor hid_descriptor;
};
struct synthhid_device_info_ack {
struct synthhid_msg_hdr header;
unsigned char reserved;
};
struct synthhid_input_report {
struct synthhid_msg_hdr header;
char buffer[1];
};
#pragma pack(pop)
#define INPUTVSC_SEND_RING_BUFFER_SIZE (40 * 1024)
#define INPUTVSC_RECV_RING_BUFFER_SIZE (40 * 1024)
enum pipe_prot_msg_type {
PIPE_MESSAGE_INVALID,
PIPE_MESSAGE_DATA,
PIPE_MESSAGE_MAXIMUM
};
struct pipe_prt_msg {
enum pipe_prot_msg_type type;
u32 size;
char data[1];
};
struct mousevsc_prt_msg {
enum pipe_prot_msg_type type;
u32 size;
union {
struct synthhid_protocol_request request;
struct synthhid_protocol_response response;
struct synthhid_device_info_ack ack;
};
};
/*
* Represents an mousevsc device
*/
struct mousevsc_dev {
struct hv_device *device;
bool init_complete;
bool connected;
struct mousevsc_prt_msg protocol_req;
struct mousevsc_prt_msg protocol_resp;
/* Synchronize the request/response if needed */
struct completion wait_event;
int dev_info_status;
struct hid_descriptor *hid_desc;
unsigned char *report_desc;
u32 report_desc_size;
struct hv_input_dev_info hid_dev_info;
struct hid_device *hid_device;
u8 input_buf[HID_MAX_BUFFER_SIZE];
};
static struct mousevsc_dev *mousevsc_alloc_device(struct hv_device *device)
{
struct mousevsc_dev *input_dev;
input_dev = kzalloc(sizeof(struct mousevsc_dev), GFP_KERNEL);
if (!input_dev)
return NULL;
input_dev->device = device;
hv_set_drvdata(device, input_dev);
init_completion(&input_dev->wait_event);
input_dev->init_complete = false;
return input_dev;
}
static void mousevsc_free_device(struct mousevsc_dev *device)
{
kfree(device->hid_desc);
kfree(device->report_desc);
hv_set_drvdata(device->device, NULL);
kfree(device);
}
static void mousevsc_on_receive_device_info(struct mousevsc_dev *input_device,
struct synthhid_device_info *device_info)
{
int ret = 0;
struct hid_descriptor *desc;
struct mousevsc_prt_msg ack;
input_device->dev_info_status = -ENOMEM;
input_device->hid_dev_info = device_info->hid_dev_info;
desc = &device_info->hid_descriptor;
if (desc->bLength == 0)
goto cleanup;
/* The pointer is not NULL when we resume from hibernation */
kfree(input_device->hid_desc);
input_device->hid_desc = kmemdup(desc, desc->bLength, GFP_ATOMIC);
if (!input_device->hid_desc)
goto cleanup;
input_device->report_desc_size = desc->desc[0].wDescriptorLength;
if (input_device->report_desc_size == 0) {
input_device->dev_info_status = -EINVAL;
goto cleanup;
}
/* The pointer is not NULL when we resume from hibernation */
kfree(input_device->report_desc);
input_device->report_desc = kzalloc(input_device->report_desc_size,
GFP_ATOMIC);
if (!input_device->report_desc) {
input_device->dev_info_status = -ENOMEM;
goto cleanup;
}
memcpy(input_device->report_desc,
((unsigned char *)desc) + desc->bLength,
desc->desc[0].wDescriptorLength);
/* Send the ack */
memset(&ack, 0, sizeof(struct mousevsc_prt_msg));
ack.type = PIPE_MESSAGE_DATA;
ack.size = sizeof(struct synthhid_device_info_ack);
ack.ack.header.type = SYNTH_HID_INITIAL_DEVICE_INFO_ACK;
ack.ack.header.size = 1;
ack.ack.reserved = 0;
ret = vmbus_sendpacket(input_device->device->channel,
&ack,
sizeof(struct pipe_prt_msg) - sizeof(unsigned char) +
sizeof(struct synthhid_device_info_ack),
(unsigned long)&ack,
VM_PKT_DATA_INBAND,
VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
if (!ret)
input_device->dev_info_status = 0;
cleanup:
complete(&input_device->wait_event);
return;
}
static void mousevsc_on_receive(struct hv_device *device,
struct vmpacket_descriptor *packet)
{
struct pipe_prt_msg *pipe_msg;
struct synthhid_msg *hid_msg;
struct mousevsc_dev *input_dev = hv_get_drvdata(device);
struct synthhid_input_report *input_report;
size_t len;
pipe_msg = (struct pipe_prt_msg *)((unsigned long)packet +
(packet->offset8 << 3));
if (pipe_msg->type != PIPE_MESSAGE_DATA)
return;
hid_msg = (struct synthhid_msg *)pipe_msg->data;
switch (hid_msg->header.type) {
case SYNTH_HID_PROTOCOL_RESPONSE:
/*
* While it will be impossible for us to protect against
* malicious/buggy hypervisor/host, add a check here to
* ensure we don't corrupt memory.
*/
if ((pipe_msg->size + sizeof(struct pipe_prt_msg)
- sizeof(unsigned char))
> sizeof(struct mousevsc_prt_msg)) {
WARN_ON(1);
break;
}
memcpy(&input_dev->protocol_resp, pipe_msg,
pipe_msg->size + sizeof(struct pipe_prt_msg) -
sizeof(unsigned char));
complete(&input_dev->wait_event);
break;
case SYNTH_HID_INITIAL_DEVICE_INFO:
WARN_ON(pipe_msg->size < sizeof(struct hv_input_dev_info));
/*
* Parse out the device info into device attr,
* hid desc and report desc
*/
mousevsc_on_receive_device_info(input_dev,
(struct synthhid_device_info *)pipe_msg->data);
break;
case SYNTH_HID_INPUT_REPORT:
input_report =
(struct synthhid_input_report *)pipe_msg->data;
if (!input_dev->init_complete)
break;
len = min(input_report->header.size,
(u32)sizeof(input_dev->input_buf));
memcpy(input_dev->input_buf, input_report->buffer, len);
hid_input_report(input_dev->hid_device, HID_INPUT_REPORT,
input_dev->input_buf, len, 1);
pm_wakeup_hard_event(&input_dev->device->device);
break;
default:
pr_err("unsupported hid msg type - type %d len %d\n",
hid_msg->header.type, hid_msg->header.size);
break;
}
}
static void mousevsc_on_channel_callback(void *context)
{
struct hv_device *device = context;
struct vmpacket_descriptor *desc;
foreach_vmbus_pkt(desc, device->channel) {
switch (desc->type) {
case VM_PKT_COMP:
break;
case VM_PKT_DATA_INBAND:
mousevsc_on_receive(device, desc);
break;
default:
pr_err("Unhandled packet type %d, tid %llx len %d\n",
desc->type, desc->trans_id, desc->len8 * 8);
break;
}
}
}
static int mousevsc_connect_to_vsp(struct hv_device *device)
{
int ret = 0;
unsigned long t;
struct mousevsc_dev *input_dev = hv_get_drvdata(device);
struct mousevsc_prt_msg *request;
struct mousevsc_prt_msg *response;
reinit_completion(&input_dev->wait_event);
request = &input_dev->protocol_req;
memset(request, 0, sizeof(struct mousevsc_prt_msg));
request->type = PIPE_MESSAGE_DATA;
request->size = sizeof(struct synthhid_protocol_request);
request->request.header.type = SYNTH_HID_PROTOCOL_REQUEST;
request->request.header.size = sizeof(unsigned int);
request->request.version_requested.version = SYNTHHID_INPUT_VERSION;
ret = vmbus_sendpacket(device->channel, request,
sizeof(struct pipe_prt_msg) -
sizeof(unsigned char) +
sizeof(struct synthhid_protocol_request),
(unsigned long)request,
VM_PKT_DATA_INBAND,
VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
if (ret)
goto cleanup;
t = wait_for_completion_timeout(&input_dev->wait_event, 5*HZ);
if (!t) {
ret = -ETIMEDOUT;
goto cleanup;
}
response = &input_dev->protocol_resp;
if (!response->response.approved) {
pr_err("synthhid protocol request failed (version %d)\n",
SYNTHHID_INPUT_VERSION);
ret = -ENODEV;
goto cleanup;
}
t = wait_for_completion_timeout(&input_dev->wait_event, 5*HZ);
if (!t) {
ret = -ETIMEDOUT;
goto cleanup;
}
/*
* We should have gotten the device attr, hid desc and report
* desc at this point
*/
ret = input_dev->dev_info_status;
cleanup:
return ret;
}
static int mousevsc_hid_parse(struct hid_device *hid)
{
struct hv_device *dev = hid_get_drvdata(hid);
struct mousevsc_dev *input_dev = hv_get_drvdata(dev);
return hid_parse_report(hid, input_dev->report_desc,
input_dev->report_desc_size);
}
static int mousevsc_hid_open(struct hid_device *hid)
{
return 0;
}
static int mousevsc_hid_start(struct hid_device *hid)
{
return 0;
}
static void mousevsc_hid_close(struct hid_device *hid)
{
}
static void mousevsc_hid_stop(struct hid_device *hid)
{
}
static int mousevsc_hid_raw_request(struct hid_device *hid,
unsigned char report_num,
__u8 *buf, size_t len,
unsigned char rtype,
int reqtype)
{
return 0;
}
static struct hid_ll_driver mousevsc_ll_driver = {
.parse = mousevsc_hid_parse,
.open = mousevsc_hid_open,
.close = mousevsc_hid_close,
.start = mousevsc_hid_start,
.stop = mousevsc_hid_stop,
.raw_request = mousevsc_hid_raw_request,
};
static struct hid_driver mousevsc_hid_driver;
static int mousevsc_probe(struct hv_device *device,
const struct hv_vmbus_device_id *dev_id)
{
int ret;
struct mousevsc_dev *input_dev;
struct hid_device *hid_dev;
input_dev = mousevsc_alloc_device(device);
if (!input_dev)
return -ENOMEM;
ret = vmbus_open(device->channel,
INPUTVSC_SEND_RING_BUFFER_SIZE,
INPUTVSC_RECV_RING_BUFFER_SIZE,
NULL,
0,
mousevsc_on_channel_callback,
device
);
if (ret)
goto probe_err0;
ret = mousevsc_connect_to_vsp(device);
if (ret)
goto probe_err1;
/* workaround SA-167 */
if (input_dev->report_desc[14] == 0x25)
input_dev->report_desc[14] = 0x29;
hid_dev = hid_allocate_device();
if (IS_ERR(hid_dev)) {
ret = PTR_ERR(hid_dev);
goto probe_err1;
}
hid_dev->ll_driver = &mousevsc_ll_driver;
hid_dev->driver = &mousevsc_hid_driver;
hid_dev->bus = BUS_VIRTUAL;
hid_dev->vendor = input_dev->hid_dev_info.vendor;
hid_dev->product = input_dev->hid_dev_info.product;
hid_dev->version = input_dev->hid_dev_info.version;
input_dev->hid_device = hid_dev;
sprintf(hid_dev->name, "%s", "Microsoft Vmbus HID-compliant Mouse");
hid_set_drvdata(hid_dev, device);
ret = hid_add_device(hid_dev);
if (ret)
goto probe_err1;
ret = hid_parse(hid_dev);
if (ret) {
hid_err(hid_dev, "parse failed\n");
goto probe_err2;
}
ret = hid_hw_start(hid_dev, HID_CONNECT_HIDINPUT | HID_CONNECT_HIDDEV);
if (ret) {
hid_err(hid_dev, "hw start failed\n");
goto probe_err2;
}
device_init_wakeup(&device->device, true);
input_dev->connected = true;
input_dev->init_complete = true;
return ret;
probe_err2:
hid_destroy_device(hid_dev);
probe_err1:
vmbus_close(device->channel);
probe_err0:
mousevsc_free_device(input_dev);
return ret;
}
static int mousevsc_remove(struct hv_device *dev)
{
struct mousevsc_dev *input_dev = hv_get_drvdata(dev);
device_init_wakeup(&dev->device, false);
vmbus_close(dev->channel);
hid_hw_stop(input_dev->hid_device);
hid_destroy_device(input_dev->hid_device);
mousevsc_free_device(input_dev);
return 0;
}
static int mousevsc_suspend(struct hv_device *dev)
{
vmbus_close(dev->channel);
return 0;
}
static int mousevsc_resume(struct hv_device *dev)
{
int ret;
ret = vmbus_open(dev->channel,
INPUTVSC_SEND_RING_BUFFER_SIZE,
INPUTVSC_RECV_RING_BUFFER_SIZE,
NULL, 0,
mousevsc_on_channel_callback,
dev);
if (ret)
return ret;
ret = mousevsc_connect_to_vsp(dev);
return ret;
}
static const struct hv_vmbus_device_id id_table[] = {
/* Mouse guid */
{ HV_MOUSE_GUID, },
{ },
};
MODULE_DEVICE_TABLE(vmbus, id_table);
static struct hv_driver mousevsc_drv = {
.name = KBUILD_MODNAME,
.id_table = id_table,
.probe = mousevsc_probe,
.remove = mousevsc_remove,
.suspend = mousevsc_suspend,
.resume = mousevsc_resume,
.driver = {
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
},
};
static int __init mousevsc_init(void)
{
return vmbus_driver_register(&mousevsc_drv);
}
static void __exit mousevsc_exit(void)
{
vmbus_driver_unregister(&mousevsc_drv);
}
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Microsoft Hyper-V Synthetic HID Driver");
module_init(mousevsc_init);
module_exit(mousevsc_exit);