// SPDX-License-Identifier: GPL-2.0 OR MIT
/*
* Copyright 2016 VMware, Inc., Palo Alto, CA., USA
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sub license, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial portions
* of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
* USE OR OTHER DEALINGS IN THE SOFTWARE.
*
*/
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/frame.h>
#include <asm/hypervisor.h>
#include <drm/drmP.h>
#include "vmwgfx_drv.h"
#include "vmwgfx_msg.h"
#define MESSAGE_STATUS_SUCCESS 0x0001
#define MESSAGE_STATUS_DORECV 0x0002
#define MESSAGE_STATUS_CPT 0x0010
#define MESSAGE_STATUS_HB 0x0080
#define RPCI_PROTOCOL_NUM 0x49435052
#define GUESTMSG_FLAG_COOKIE 0x80000000
#define RETRIES 3
#define VMW_HYPERVISOR_MAGIC 0x564D5868
#define VMW_HYPERVISOR_PORT 0x5658
#define VMW_HYPERVISOR_HB_PORT 0x5659
#define VMW_PORT_CMD_MSG 30
#define VMW_PORT_CMD_HB_MSG 0
#define VMW_PORT_CMD_OPEN_CHANNEL (MSG_TYPE_OPEN << 16 | VMW_PORT_CMD_MSG)
#define VMW_PORT_CMD_CLOSE_CHANNEL (MSG_TYPE_CLOSE << 16 | VMW_PORT_CMD_MSG)
#define VMW_PORT_CMD_SENDSIZE (MSG_TYPE_SENDSIZE << 16 | VMW_PORT_CMD_MSG)
#define VMW_PORT_CMD_RECVSIZE (MSG_TYPE_RECVSIZE << 16 | VMW_PORT_CMD_MSG)
#define VMW_PORT_CMD_RECVSTATUS (MSG_TYPE_RECVSTATUS << 16 | VMW_PORT_CMD_MSG)
#define HIGH_WORD(X) ((X & 0xFFFF0000) >> 16)
static u32 vmw_msg_enabled = 1;
enum rpc_msg_type {
MSG_TYPE_OPEN,
MSG_TYPE_SENDSIZE,
MSG_TYPE_SENDPAYLOAD,
MSG_TYPE_RECVSIZE,
MSG_TYPE_RECVPAYLOAD,
MSG_TYPE_RECVSTATUS,
MSG_TYPE_CLOSE,
};
struct rpc_channel {
u16 channel_id;
u32 cookie_high;
u32 cookie_low;
};
/**
* vmw_open_channel
*
* @channel: RPC channel
* @protocol:
*
* Returns: 0 on success
*/
static int vmw_open_channel(struct rpc_channel *channel, unsigned int protocol)
{
unsigned long eax, ebx, ecx, edx, si = 0, di = 0;
VMW_PORT(VMW_PORT_CMD_OPEN_CHANNEL,
(protocol | GUESTMSG_FLAG_COOKIE), si, di,
VMW_HYPERVISOR_PORT,
VMW_HYPERVISOR_MAGIC,
eax, ebx, ecx, edx, si, di);
if ((HIGH_WORD(ecx) & MESSAGE_STATUS_SUCCESS) == 0)
return -EINVAL;
channel->channel_id = HIGH_WORD(edx);
channel->cookie_high = si;
channel->cookie_low = di;
return 0;
}
/**
* vmw_close_channel
*
* @channel: RPC channel
*
* Returns: 0 on success
*/
static int vmw_close_channel(struct rpc_channel *channel)
{
unsigned long eax, ebx, ecx, edx, si, di;
/* Set up additional parameters */
si = channel->cookie_high;
di = channel->cookie_low;
VMW_PORT(VMW_PORT_CMD_CLOSE_CHANNEL,
0, si, di,
(VMW_HYPERVISOR_PORT | (channel->channel_id << 16)),
VMW_HYPERVISOR_MAGIC,
eax, ebx, ecx, edx, si, di);
if ((HIGH_WORD(ecx) & MESSAGE_STATUS_SUCCESS) == 0)
return -EINVAL;
return 0;
}
/**
* vmw_port_hb_out - Send the message payload either through the
* high-bandwidth port if available, or through the backdoor otherwise.
* @channel: The rpc channel.
* @msg: NULL-terminated message.
* @hb: Whether the high-bandwidth port is available.
*
* Return: The port status.
*/
static unsigned long vmw_port_hb_out(struct rpc_channel *channel,
const char *msg, bool hb)
{
unsigned long si, di, eax, ebx, ecx, edx;
unsigned long msg_len = strlen(msg);
if (hb) {
unsigned long bp = channel->cookie_high;
si = (uintptr_t) msg;
di = channel->cookie_low;
VMW_PORT_HB_OUT(
(MESSAGE_STATUS_SUCCESS << 16) | VMW_PORT_CMD_HB_MSG,
msg_len, si, di,
VMW_HYPERVISOR_HB_PORT | (channel->channel_id << 16),
VMW_HYPERVISOR_MAGIC, bp,
eax, ebx, ecx, edx, si, di);
return ebx;
}
/* HB port not available. Send the message 4 bytes at a time. */
ecx = MESSAGE_STATUS_SUCCESS << 16;
while (msg_len && (HIGH_WORD(ecx) & MESSAGE_STATUS_SUCCESS)) {
unsigned int bytes = min_t(size_t, msg_len, 4);
unsigned long word = 0;
memcpy(&word, msg, bytes);
msg_len -= bytes;
msg += bytes;
si = channel->cookie_high;
di = channel->cookie_low;
VMW_PORT(VMW_PORT_CMD_MSG | (MSG_TYPE_SENDPAYLOAD << 16),
word, si, di,
VMW_HYPERVISOR_PORT | (channel->channel_id << 16),
VMW_HYPERVISOR_MAGIC,
eax, ebx, ecx, edx, si, di);
}
return ecx;
}
/**
* vmw_port_hb_in - Receive the message payload either through the
* high-bandwidth port if available, or through the backdoor otherwise.
* @channel: The rpc channel.
* @reply: Pointer to buffer holding reply.
* @reply_len: Length of the reply.
* @hb: Whether the high-bandwidth port is available.
*
* Return: The port status.
*/
static unsigned long vmw_port_hb_in(struct rpc_channel *channel, char *reply,
unsigned long reply_len, bool hb)
{
unsigned long si, di, eax, ebx, ecx, edx;
if (hb) {
unsigned long bp = channel->cookie_low;
si = channel->cookie_high;
di = (uintptr_t) reply;
VMW_PORT_HB_IN(
(MESSAGE_STATUS_SUCCESS << 16) | VMW_PORT_CMD_HB_MSG,
reply_len, si, di,
VMW_HYPERVISOR_HB_PORT | (channel->channel_id << 16),
VMW_HYPERVISOR_MAGIC, bp,
eax, ebx, ecx, edx, si, di);
return ebx;
}
/* HB port not available. Retrieve the message 4 bytes at a time. */
ecx = MESSAGE_STATUS_SUCCESS << 16;
while (reply_len) {
unsigned int bytes = min_t(unsigned long, reply_len, 4);
si = channel->cookie_high;
di = channel->cookie_low;
VMW_PORT(VMW_PORT_CMD_MSG | (MSG_TYPE_RECVPAYLOAD << 16),
MESSAGE_STATUS_SUCCESS, si, di,
VMW_HYPERVISOR_PORT | (channel->channel_id << 16),
VMW_HYPERVISOR_MAGIC,
eax, ebx, ecx, edx, si, di);
if ((HIGH_WORD(ecx) & MESSAGE_STATUS_SUCCESS) == 0)
break;
memcpy(reply, &ebx, bytes);
reply_len -= bytes;
reply += bytes;
}
return ecx;
}
/**
* vmw_send_msg: Sends a message to the host
*
* @channel: RPC channel
* @logmsg: NULL terminated string
*
* Returns: 0 on success
*/
static int vmw_send_msg(struct rpc_channel *channel, const char *msg)
{
unsigned long eax, ebx, ecx, edx, si, di;
size_t msg_len = strlen(msg);
int retries = 0;
while (retries < RETRIES) {
retries++;
/* Set up additional parameters */
si = channel->cookie_high;
di = channel->cookie_low;
VMW_PORT(VMW_PORT_CMD_SENDSIZE,
msg_len, si, di,
VMW_HYPERVISOR_PORT | (channel->channel_id << 16),
VMW_HYPERVISOR_MAGIC,
eax, ebx, ecx, edx, si, di);
if ((HIGH_WORD(ecx) & MESSAGE_STATUS_SUCCESS) == 0) {
/* Expected success. Give up. */
return -EINVAL;
}
/* Send msg */
ebx = vmw_port_hb_out(channel, msg,
!!(HIGH_WORD(ecx) & MESSAGE_STATUS_HB));
if ((HIGH_WORD(ebx) & MESSAGE_STATUS_SUCCESS) != 0) {
return 0;
} else if ((HIGH_WORD(ebx) & MESSAGE_STATUS_CPT) != 0) {
/* A checkpoint occurred. Retry. */
continue;
} else {
break;
}
}
return -EINVAL;
}
STACK_FRAME_NON_STANDARD(vmw_send_msg);
/**
* vmw_recv_msg: Receives a message from the host
*
* Note: It is the caller's responsibility to call kfree() on msg.
*
* @channel: channel opened by vmw_open_channel
* @msg: [OUT] message received from the host
* @msg_len: message length
*/
static int vmw_recv_msg(struct rpc_channel *channel, void **msg,
size_t *msg_len)
{
unsigned long eax, ebx, ecx, edx, si, di;
char *reply;
size_t reply_len;
int retries = 0;
*msg_len = 0;
*msg = NULL;
while (retries < RETRIES) {
retries++;
/* Set up additional parameters */
si = channel->cookie_high;
di = channel->cookie_low;
VMW_PORT(VMW_PORT_CMD_RECVSIZE,
0, si, di,
(VMW_HYPERVISOR_PORT | (channel->channel_id << 16)),
VMW_HYPERVISOR_MAGIC,
eax, ebx, ecx, edx, si, di);
if ((HIGH_WORD(ecx) & MESSAGE_STATUS_SUCCESS) == 0) {
DRM_ERROR("Failed to get reply size for host message.\n");
return -EINVAL;
}
/* No reply available. This is okay. */
if ((HIGH_WORD(ecx) & MESSAGE_STATUS_DORECV) == 0)
return 0;
reply_len = ebx;
reply = kzalloc(reply_len + 1, GFP_KERNEL);
if (!reply) {
DRM_ERROR("Cannot allocate memory for host message reply.\n");
return -ENOMEM;
}
/* Receive buffer */
ebx = vmw_port_hb_in(channel, reply, reply_len,
!!(HIGH_WORD(ecx) & MESSAGE_STATUS_HB));
if ((HIGH_WORD(ebx) & MESSAGE_STATUS_SUCCESS) == 0) {
kfree(reply);
if ((HIGH_WORD(ebx) & MESSAGE_STATUS_CPT) != 0) {
/* A checkpoint occurred. Retry. */
continue;
}
return -EINVAL;
}
reply[reply_len] = '\0';
/* Ack buffer */
si = channel->cookie_high;
di = channel->cookie_low;
VMW_PORT(VMW_PORT_CMD_RECVSTATUS,
MESSAGE_STATUS_SUCCESS, si, di,
(VMW_HYPERVISOR_PORT | (channel->channel_id << 16)),
VMW_HYPERVISOR_MAGIC,
eax, ebx, ecx, edx, si, di);
if ((HIGH_WORD(ecx) & MESSAGE_STATUS_SUCCESS) == 0) {
kfree(reply);
if ((HIGH_WORD(ecx) & MESSAGE_STATUS_CPT) != 0) {
/* A checkpoint occurred. Retry. */
continue;
}
return -EINVAL;
}
break;
}
if (retries == RETRIES) {
kfree(reply);
return -EINVAL;
}
*msg_len = reply_len;
*msg = reply;
return 0;
}
STACK_FRAME_NON_STANDARD(vmw_recv_msg);
/**
* vmw_host_get_guestinfo: Gets a GuestInfo parameter
*
* Gets the value of a GuestInfo.* parameter. The value returned will be in
* a string, and it is up to the caller to post-process.
*
* @guest_info_param: Parameter to get, e.g. GuestInfo.svga.gl3
* @buffer: if NULL, *reply_len will contain reply size.
* @length: size of the reply_buf. Set to size of reply upon return
*
* Returns: 0 on success
*/
int vmw_host_get_guestinfo(const char *guest_info_param,
char *buffer, size_t *length)
{
struct rpc_channel channel;
char *msg, *reply = NULL;
size_t reply_len = 0;
if (!vmw_msg_enabled)
return -ENODEV;
if (!guest_info_param || !length)
return -EINVAL;
msg = kasprintf(GFP_KERNEL, "info-get %s", guest_info_param);
if (!msg) {
DRM_ERROR("Cannot allocate memory to get guest info \"%s\".",
guest_info_param);
return -ENOMEM;
}
if (vmw_open_channel(&channel, RPCI_PROTOCOL_NUM))
goto out_open;
if (vmw_send_msg(&channel, msg) ||
vmw_recv_msg(&channel, (void *) &reply, &reply_len))
goto out_msg;
vmw_close_channel(&channel);
if (buffer && reply && reply_len > 0) {
/* Remove reply code, which are the first 2 characters of
* the reply
*/
reply_len = max(reply_len - 2, (size_t) 0);
reply_len = min(reply_len, *length);
if (reply_len > 0)
memcpy(buffer, reply + 2, reply_len);
}
*length = reply_len;
kfree(reply);
kfree(msg);
return 0;
out_msg:
vmw_close_channel(&channel);
kfree(reply);
out_open:
*length = 0;
kfree(msg);
DRM_ERROR("Failed to get guest info \"%s\".", guest_info_param);
return -EINVAL;
}
/**
* vmw_host_log: Sends a log message to the host
*
* @log: NULL terminated string
*
* Returns: 0 on success
*/
int vmw_host_log(const char *log)
{
struct rpc_channel channel;
char *msg;
int ret = 0;
if (!vmw_msg_enabled)
return -ENODEV;
if (!log)
return ret;
msg = kasprintf(GFP_KERNEL, "log %s", log);
if (!msg) {
DRM_ERROR("Cannot allocate memory for host log message.\n");
return -ENOMEM;
}
if (vmw_open_channel(&channel, RPCI_PROTOCOL_NUM))
goto out_open;
if (vmw_send_msg(&channel, msg))
goto out_msg;
vmw_close_channel(&channel);
kfree(msg);
return 0;
out_msg:
vmw_close_channel(&channel);
out_open:
kfree(msg);
DRM_ERROR("Failed to send host log message.\n");
return -EINVAL;
}
