[linux-2.6-block.git] / drivers / gpu / drm / vmwgfx / vmwgfx_msg.c

// 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/objtool.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/mem_encrypt.h>

#include <asm/hypervisor.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_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)

#define MAX_USER_MSG_LENGTH	PAGE_SIZE

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,
		0,
		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,
		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);

	/* HB port can't access encrypted memory. */
	if (hb && !mem_encrypt_active()) {
		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,
			VMWARE_HYPERVISOR_HB | (channel->channel_id << 16) |
			VMWARE_HYPERVISOR_OUT,
			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,
			 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;

	/* HB port can't access encrypted memory */
	if (hb && !mem_encrypt_active()) {
		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,
			VMWARE_HYPERVISOR_HB | (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,
			 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,
			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,
			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);
			reply = NULL;
			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,
			channel->channel_id << 16,
			VMW_HYPERVISOR_MAGIC,
			eax, ebx, ecx, edx, si, di);

		if ((HIGH_WORD(ecx) & MESSAGE_STATUS_SUCCESS) == 0) {
			kfree(reply);
			reply = NULL;
			if ((HIGH_WORD(ecx) & MESSAGE_STATUS_CPT) != 0) {
				/* A checkpoint occurred. Retry. */
				continue;
			}

			return -EINVAL;
		}

		break;
	}

	if (!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;
}


/**
 * vmw_msg_ioctl: Sends and receveives a message to/from host from/to user-space
 *
 * Sends a message from user-space to host.
 * Can also receive a result from host and return that to user-space.
 *
 * @dev: Identifies the drm device.
 * @data: Pointer to the ioctl argument.
 * @file_priv: Identifies the caller.
 * Return: Zero on success, negative error code on error.
 */

int vmw_msg_ioctl(struct drm_device *dev, void *data,
		  struct drm_file *file_priv)
{
	struct drm_vmw_msg_arg *arg =
		(struct drm_vmw_msg_arg *) data;
	struct rpc_channel channel;
	char *msg;
	int length;

	msg = kmalloc(MAX_USER_MSG_LENGTH, GFP_KERNEL);
	if (!msg) {
		DRM_ERROR("Cannot allocate memory for log message.\n");
		return -ENOMEM;
	}

	length = strncpy_from_user(msg, (void __user *)((unsigned long)arg->send),
				   MAX_USER_MSG_LENGTH);
	if (length < 0 || length >= MAX_USER_MSG_LENGTH) {
		DRM_ERROR("Userspace message access failure.\n");
		kfree(msg);
		return -EINVAL;
	}


	if (vmw_open_channel(&channel, RPCI_PROTOCOL_NUM)) {
		DRM_ERROR("Failed to open channel.\n");
		goto out_open;
	}

	if (vmw_send_msg(&channel, msg)) {
		DRM_ERROR("Failed to send message to host.\n");
		goto out_msg;
	}

	if (!arg->send_only) {
		char *reply = NULL;
		size_t reply_len = 0;

		if (vmw_recv_msg(&channel, (void *) &reply, &reply_len)) {
			DRM_ERROR("Failed to receive message from host.\n");
			goto out_msg;
		}
		if (reply && reply_len > 0) {
			if (copy_to_user((void __user *)((unsigned long)arg->receive),
							 reply, reply_len)) {
				DRM_ERROR("Failed to copy message to userspace.\n");
				kfree(reply);
				goto out_msg;
			}
			arg->receive_len = (__u32)reply_len;
		}
		kfree(reply);
	}

	vmw_close_channel(&channel);
	kfree(msg);

	return 0;

out_msg:
	vmw_close_channel(&channel);
out_open:
	kfree(msg);

	return -EINVAL;
}
Commit	Line	Data
dff96888	1	// SPDX-License-Identifier: GPL-2.0 OR MIT
89da76fd	2	/*
dff96888	3	* Copyright 2016 VMware, Inc., Palo Alto, CA., USA
89da76fd SY	4	*
	5	* Permission is hereby granted, free of charge, to any person obtaining a
	6	* copy of this software and associated documentation files (the
	7	* "Software"), to deal in the Software without restriction, including
	8	* without limitation the rights to use, copy, modify, merge, publish,
	9	* distribute, sub license, and/or sell copies of the Software, and to
	10	* permit persons to whom the Software is furnished to do so, subject to
	11	* the following conditions:
	12	*
	13	* The above copyright notice and this permission notice (including the
	14	* next paragraph) shall be included in all copies or substantial portions
	15	* of the Software.
	16	*
	17	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	18	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	19	* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
	20	* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
	21	* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
	22	* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
	23	* USE OR OTHER DEALINGS IN THE SOFTWARE.
	24	*
	25	*/
	26
00089c04	27	#include <linux/objtool.h>
6ae8748b SR	28	#include <linux/kernel.h>
	29	#include <linux/module.h>
	30	#include <linux/slab.h>
af4eaf10	31	#include <linux/mem_encrypt.h>
6ae8748b	32
89da76fd	33	#include <asm/hypervisor.h>
6ae8748b	34
6ff67ae7	35	#include "vmwgfx_drv.h"
89da76fd SY	36	#include "vmwgfx_msg.h"
89da76fd SY	37
89da76fd SY	38	#define MESSAGE_STATUS_SUCCESS 0x0001
	39	#define MESSAGE_STATUS_DORECV 0x0002
	40	#define MESSAGE_STATUS_CPT 0x0010
	41	#define MESSAGE_STATUS_HB 0x0080
	42
	43	#define RPCI_PROTOCOL_NUM 0x49435052
	44	#define GUESTMSG_FLAG_COOKIE 0x80000000
	45
	46	#define RETRIES 3
	47
	48	#define VMW_HYPERVISOR_MAGIC 0x564D5868
89da76fd SY	49
	50	#define VMW_PORT_CMD_MSG 30
	51	#define VMW_PORT_CMD_HB_MSG 0
	52	#define VMW_PORT_CMD_OPEN_CHANNEL (MSG_TYPE_OPEN << 16 \| VMW_PORT_CMD_MSG)
	53	#define VMW_PORT_CMD_CLOSE_CHANNEL (MSG_TYPE_CLOSE << 16 \| VMW_PORT_CMD_MSG)
	54	#define VMW_PORT_CMD_SENDSIZE (MSG_TYPE_SENDSIZE << 16 \| VMW_PORT_CMD_MSG)
	55	#define VMW_PORT_CMD_RECVSIZE (MSG_TYPE_RECVSIZE << 16 \| VMW_PORT_CMD_MSG)
	56	#define VMW_PORT_CMD_RECVSTATUS (MSG_TYPE_RECVSTATUS << 16 \| VMW_PORT_CMD_MSG)
	57
	58	#define HIGH_WORD(X) ((X & 0xFFFF0000) >> 16)
	59
cb92a323 RS	60	#define MAX_USER_MSG_LENGTH PAGE_SIZE
cb92a323 RS	61
89da76fd SY	62	static u32 vmw_msg_enabled = 1;
	63
	64	enum rpc_msg_type {
	65	MSG_TYPE_OPEN,
	66	MSG_TYPE_SENDSIZE,
	67	MSG_TYPE_SENDPAYLOAD,
	68	MSG_TYPE_RECVSIZE,
	69	MSG_TYPE_RECVPAYLOAD,
	70	MSG_TYPE_RECVSTATUS,
	71	MSG_TYPE_CLOSE,
	72	};
	73
	74	struct rpc_channel {
	75	u16 channel_id;
	76	u32 cookie_high;
	77	u32 cookie_low;
	78	};
	79
	80
	81
	82	/**
	83	* vmw_open_channel
	84	*
	85	* @channel: RPC channel
	86	* @protocol:
	87	*
	88	* Returns: 0 on success
	89	*/
	90	static int vmw_open_channel(struct rpc_channel *channel, unsigned int protocol)
	91	{
	92	unsigned long eax, ebx, ecx, edx, si = 0, di = 0;
	93
	94	VMW_PORT(VMW_PORT_CMD_OPEN_CHANNEL,
	95	(protocol \| GUESTMSG_FLAG_COOKIE), si, di,
6abe3778	96	0,
89da76fd SY	97	VMW_HYPERVISOR_MAGIC,
	98	eax, ebx, ecx, edx, si, di);
	99
	100	if ((HIGH_WORD(ecx) & MESSAGE_STATUS_SUCCESS) == 0)
	101	return -EINVAL;
	102
	103	channel->channel_id = HIGH_WORD(edx);
	104	channel->cookie_high = si;
	105	channel->cookie_low = di;
	106
	107	return 0;
	108	}
	109
	110
	111
	112	/**
	113	* vmw_close_channel
	114	*
	115	* @channel: RPC channel
	116	*
	117	* Returns: 0 on success
	118	*/
	119	static int vmw_close_channel(struct rpc_channel *channel)
	120	{
	121	unsigned long eax, ebx, ecx, edx, si, di;
	122
	123	/* Set up additional parameters */
	124	si = channel->cookie_high;
	125	di = channel->cookie_low;
	126
	127	VMW_PORT(VMW_PORT_CMD_CLOSE_CHANNEL,
	128	0, si, di,
6abe3778	129	channel->channel_id << 16,
89da76fd SY	130	VMW_HYPERVISOR_MAGIC,
	131	eax, ebx, ecx, edx, si, di);
	132
	133	if ((HIGH_WORD(ecx) & MESSAGE_STATUS_SUCCESS) == 0)
	134	return -EINVAL;
	135
	136	return 0;
	137	}
	138
cc0ba0d8 TH	139	/**
	140	* vmw_port_hb_out - Send the message payload either through the
	141	* high-bandwidth port if available, or through the backdoor otherwise.
	142	* @channel: The rpc channel.
	143	* @msg: NULL-terminated message.
	144	* @hb: Whether the high-bandwidth port is available.
	145	*
	146	* Return: The port status.
	147	*/
	148	static unsigned long vmw_port_hb_out(struct rpc_channel *channel,
	149	const char *msg, bool hb)
	150	{
	151	unsigned long si, di, eax, ebx, ecx, edx;
	152	unsigned long msg_len = strlen(msg);
	153
af4eaf10 TH	154	/* HB port can't access encrypted memory. */
af4eaf10 TH	155	if (hb && !mem_encrypt_active()) {
cc0ba0d8 TH	156	unsigned long bp = channel->cookie_high;
	157
	158	si = (uintptr_t) msg;
	159	di = channel->cookie_low;
	160
	161	VMW_PORT_HB_OUT(
	162	(MESSAGE_STATUS_SUCCESS << 16) \| VMW_PORT_CMD_HB_MSG,
	163	msg_len, si, di,
6abe3778 TH	164	VMWARE_HYPERVISOR_HB \| (channel->channel_id << 16) \|
6abe3778 TH	165	VMWARE_HYPERVISOR_OUT,
cc0ba0d8 TH	166	VMW_HYPERVISOR_MAGIC, bp,
	167	eax, ebx, ecx, edx, si, di);
	168
	169	return ebx;
	170	}
	171
	172	/* HB port not available. Send the message 4 bytes at a time. */
	173	ecx = MESSAGE_STATUS_SUCCESS << 16;
	174	while (msg_len && (HIGH_WORD(ecx) & MESSAGE_STATUS_SUCCESS)) {
	175	unsigned int bytes = min_t(size_t, msg_len, 4);
	176	unsigned long word = 0;
	177
	178	memcpy(&word, msg, bytes);
	179	msg_len -= bytes;
	180	msg += bytes;
	181	si = channel->cookie_high;
	182	di = channel->cookie_low;
	183
	184	VMW_PORT(VMW_PORT_CMD_MSG \| (MSG_TYPE_SENDPAYLOAD << 16),
	185	word, si, di,
6abe3778	186	channel->channel_id << 16,
cc0ba0d8 TH	187	VMW_HYPERVISOR_MAGIC,
	188	eax, ebx, ecx, edx, si, di);
	189	}
	190
	191	return ecx;
	192	}
	193
	194	/**
	195	* vmw_port_hb_in - Receive the message payload either through the
	196	* high-bandwidth port if available, or through the backdoor otherwise.
	197	* @channel: The rpc channel.
	198	* @reply: Pointer to buffer holding reply.
	199	* @reply_len: Length of the reply.
	200	* @hb: Whether the high-bandwidth port is available.
	201	*
	202	* Return: The port status.
	203	*/
	204	static unsigned long vmw_port_hb_in(struct rpc_channel channel, char reply,
	205	unsigned long reply_len, bool hb)
	206	{
	207	unsigned long si, di, eax, ebx, ecx, edx;
	208
af4eaf10 TH	209	/* HB port can't access encrypted memory */
af4eaf10 TH	210	if (hb && !mem_encrypt_active()) {
cc0ba0d8 TH	211	unsigned long bp = channel->cookie_low;
	212
	213	si = channel->cookie_high;
	214	di = (uintptr_t) reply;
	215
	216	VMW_PORT_HB_IN(
	217	(MESSAGE_STATUS_SUCCESS << 16) \| VMW_PORT_CMD_HB_MSG,
	218	reply_len, si, di,
6abe3778	219	VMWARE_HYPERVISOR_HB \| (channel->channel_id << 16),
cc0ba0d8 TH	220	VMW_HYPERVISOR_MAGIC, bp,
	221	eax, ebx, ecx, edx, si, di);
	222
	223	return ebx;
	224	}
	225
	226	/* HB port not available. Retrieve the message 4 bytes at a time. */
	227	ecx = MESSAGE_STATUS_SUCCESS << 16;
	228	while (reply_len) {
	229	unsigned int bytes = min_t(unsigned long, reply_len, 4);
	230
	231	si = channel->cookie_high;
	232	di = channel->cookie_low;
	233
	234	VMW_PORT(VMW_PORT_CMD_MSG \| (MSG_TYPE_RECVPAYLOAD << 16),
	235	MESSAGE_STATUS_SUCCESS, si, di,
6abe3778	236	channel->channel_id << 16,
cc0ba0d8 TH	237	VMW_HYPERVISOR_MAGIC,
	238	eax, ebx, ecx, edx, si, di);
	239
	240	if ((HIGH_WORD(ecx) & MESSAGE_STATUS_SUCCESS) == 0)
	241	break;
	242
	243	memcpy(reply, &ebx, bytes);
	244	reply_len -= bytes;
	245	reply += bytes;
	246	}
	247
	248	return ecx;
	249	}
89da76fd SY	250
	251
	252	/**
	253	* vmw_send_msg: Sends a message to the host
	254	*
	255	* @channel: RPC channel
	256	* @logmsg: NULL terminated string
	257	*
	258	* Returns: 0 on success
	259	*/
	260	static int vmw_send_msg(struct rpc_channel channel, const char msg)
	261	{
cc0ba0d8	262	unsigned long eax, ebx, ecx, edx, si, di;
89da76fd SY	263	size_t msg_len = strlen(msg);
	264	int retries = 0;
	265
89da76fd SY	266	while (retries < RETRIES) {
	267	retries++;
	268
	269	/* Set up additional parameters */
	270	si = channel->cookie_high;
	271	di = channel->cookie_low;
	272
	273	VMW_PORT(VMW_PORT_CMD_SENDSIZE,
	274	msg_len, si, di,
6abe3778	275	channel->channel_id << 16,
89da76fd SY	276	VMW_HYPERVISOR_MAGIC,
	277	eax, ebx, ecx, edx, si, di);
	278
cc0ba0d8 TH	279	if ((HIGH_WORD(ecx) & MESSAGE_STATUS_SUCCESS) == 0) {
cc0ba0d8 TH	280	/* Expected success. Give up. */
89da76fd SY	281	return -EINVAL;
	282	}
	283
	284	/* Send msg */
cc0ba0d8 TH	285	ebx = vmw_port_hb_out(channel, msg,
cc0ba0d8 TH	286	!!(HIGH_WORD(ecx) & MESSAGE_STATUS_HB));
89da76fd SY	287
	288	if ((HIGH_WORD(ebx) & MESSAGE_STATUS_SUCCESS) != 0) {
	289	return 0;
	290	} else if ((HIGH_WORD(ebx) & MESSAGE_STATUS_CPT) != 0) {
	291	/* A checkpoint occurred. Retry. */
	292	continue;
	293	} else {
	294	break;
	295	}
	296	}
	297
	298	return -EINVAL;
	299	}
0b0d81e3	300	STACK_FRAME_NON_STANDARD(vmw_send_msg);
89da76fd SY	301
	302
	303	/**
	304	* vmw_recv_msg: Receives a message from the host
	305	*
	306	* Note: It is the caller's responsibility to call kfree() on msg.
	307	*
	308	* @channel: channel opened by vmw_open_channel
	309	* @msg: [OUT] message received from the host
	310	* @msg_len: message length
	311	*/
	312	static int vmw_recv_msg(struct rpc_channel channel, void *msg,
	313	size_t *msg_len)
	314	{
cc0ba0d8	315	unsigned long eax, ebx, ecx, edx, si, di;
89da76fd SY	316	char *reply;
	317	size_t reply_len;
	318	int retries = 0;
	319
	320
	321	*msg_len = 0;
	322	*msg = NULL;
	323
	324	while (retries < RETRIES) {
	325	retries++;
	326
	327	/* Set up additional parameters */
	328	si = channel->cookie_high;
	329	di = channel->cookie_low;
	330
	331	VMW_PORT(VMW_PORT_CMD_RECVSIZE,
	332	0, si, di,
6abe3778	333	channel->channel_id << 16,
89da76fd SY	334	VMW_HYPERVISOR_MAGIC,
	335	eax, ebx, ecx, edx, si, di);
	336
cc0ba0d8	337	if ((HIGH_WORD(ecx) & MESSAGE_STATUS_SUCCESS) == 0) {
3fbeccf8	338	DRM_ERROR("Failed to get reply size for host message.\n");
89da76fd SY	339	return -EINVAL;
	340	}
	341
	342	/* No reply available. This is okay. */
	343	if ((HIGH_WORD(ecx) & MESSAGE_STATUS_DORECV) == 0)
	344	return 0;
	345
	346	reply_len = ebx;
	347	reply = kzalloc(reply_len + 1, GFP_KERNEL);
1a4adb05	348	if (!reply) {
3fbeccf8	349	DRM_ERROR("Cannot allocate memory for host message reply.\n");
89da76fd SY	350	return -ENOMEM;
	351	}
	352
	353
	354	/* Receive buffer */
cc0ba0d8 TH	355	ebx = vmw_port_hb_in(channel, reply, reply_len,
cc0ba0d8 TH	356	!!(HIGH_WORD(ecx) & MESSAGE_STATUS_HB));
89da76fd SY	357	if ((HIGH_WORD(ebx) & MESSAGE_STATUS_SUCCESS) == 0) {
89da76fd SY	358	kfree(reply);
08b0c891	359	reply = NULL;
89da76fd SY	360	if ((HIGH_WORD(ebx) & MESSAGE_STATUS_CPT) != 0) {
	361	/* A checkpoint occurred. Retry. */
	362	continue;
	363	}
	364
	365	return -EINVAL;
	366	}
	367
	368	reply[reply_len] = '\0';
	369
	370
	371	/* Ack buffer */
	372	si = channel->cookie_high;
	373	di = channel->cookie_low;
	374
	375	VMW_PORT(VMW_PORT_CMD_RECVSTATUS,
	376	MESSAGE_STATUS_SUCCESS, si, di,
6abe3778	377	channel->channel_id << 16,
89da76fd SY	378	VMW_HYPERVISOR_MAGIC,
	379	eax, ebx, ecx, edx, si, di);
	380
	381	if ((HIGH_WORD(ecx) & MESSAGE_STATUS_SUCCESS) == 0) {
	382	kfree(reply);
08b0c891	383	reply = NULL;
89da76fd SY	384	if ((HIGH_WORD(ecx) & MESSAGE_STATUS_CPT) != 0) {
	385	/* A checkpoint occurred. Retry. */
	386	continue;
	387	}
	388
	389	return -EINVAL;
	390	}
	391
	392	break;
	393	}
	394
08b0c891	395	if (!reply)
a9cd9c04 SY	396	return -EINVAL;
a9cd9c04 SY	397
89da76fd SY	398	*msg_len = reply_len;
	399	*msg = reply;
	400
	401	return 0;
	402	}
0b0d81e3	403	STACK_FRAME_NON_STANDARD(vmw_recv_msg);
89da76fd SY	404
	405
	406	/**
	407	* vmw_host_get_guestinfo: Gets a GuestInfo parameter
	408	*
	409	* Gets the value of a GuestInfo.* parameter. The value returned will be in
	410	* a string, and it is up to the caller to post-process.
	411	*
	412	* @guest_info_param: Parameter to get, e.g. GuestInfo.svga.gl3
	413	* @buffer: if NULL, *reply_len will contain reply size.
	414	* @length: size of the reply_buf. Set to size of reply upon return
	415	*
	416	* Returns: 0 on success
	417	*/
	418	int vmw_host_get_guestinfo(const char *guest_info_param,
	419	char buffer, size_t length)
	420	{
	421	struct rpc_channel channel;
	422	char msg, reply = NULL;
6073a092	423	size_t reply_len = 0;
89da76fd SY	424
	425	if (!vmw_msg_enabled)
	426	return -ENODEV;
	427
	428	if (!guest_info_param \|\| !length)
	429	return -EINVAL;
	430
6073a092	431	msg = kasprintf(GFP_KERNEL, "info-get %s", guest_info_param);
1a4adb05	432	if (!msg) {
3fbeccf8 TH	433	DRM_ERROR("Cannot allocate memory to get guest info \"%s\".",
3fbeccf8 TH	434	guest_info_param);
89da76fd SY	435	return -ENOMEM;
	436	}
	437
f37230c0 TH	438	if (vmw_open_channel(&channel, RPCI_PROTOCOL_NUM))
f37230c0 TH	439	goto out_open;
89da76fd	440
f37230c0 TH	441	if (vmw_send_msg(&channel, msg) \|\|
	442	vmw_recv_msg(&channel, (void *) &reply, &reply_len))
	443	goto out_msg;
89da76fd	444
f37230c0	445	vmw_close_channel(&channel);
89da76fd SY	446	if (buffer && reply && reply_len > 0) {
	447	/* Remove reply code, which are the first 2 characters of
	448	* the reply
	449	*/
	450	reply_len = max(reply_len - 2, (size_t) 0);
	451	reply_len = min(reply_len, *length);
	452
	453	if (reply_len > 0)
	454	memcpy(buffer, reply + 2, reply_len);
	455	}
	456
	457	*length = reply_len;
	458
	459	kfree(reply);
	460	kfree(msg);
	461
f37230c0 TH	462	return 0;
	463
	464	out_msg:
	465	vmw_close_channel(&channel);
	466	kfree(reply);
	467	out_open:
	468	*length = 0;
	469	kfree(msg);
3fbeccf8	470	DRM_ERROR("Failed to get guest info \"%s\".", guest_info_param);
f37230c0 TH	471
f37230c0 TH	472	return -EINVAL;
89da76fd SY	473	}
	474
	475
	476
	477	/**
	478	* vmw_host_log: Sends a log message to the host
	479	*
	480	* @log: NULL terminated string
	481	*
	482	* Returns: 0 on success
	483	*/
	484	int vmw_host_log(const char *log)
	485	{
	486	struct rpc_channel channel;
	487	char *msg;
89da76fd SY	488	int ret = 0;
	489
	490
	491	if (!vmw_msg_enabled)
	492	return -ENODEV;
	493
	494	if (!log)
	495	return ret;
	496
6073a092	497	msg = kasprintf(GFP_KERNEL, "log %s", log);
1a4adb05	498	if (!msg) {
3fbeccf8	499	DRM_ERROR("Cannot allocate memory for host log message.\n");
89da76fd SY	500	return -ENOMEM;
	501	}
	502
f37230c0 TH	503	if (vmw_open_channel(&channel, RPCI_PROTOCOL_NUM))
f37230c0 TH	504	goto out_open;
89da76fd	505
f37230c0 TH	506	if (vmw_send_msg(&channel, msg))
f37230c0 TH	507	goto out_msg;
89da76fd	508
f37230c0	509	vmw_close_channel(&channel);
89da76fd SY	510	kfree(msg);
89da76fd SY	511
f37230c0 TH	512	return 0;
	513
	514	out_msg:
	515	vmw_close_channel(&channel);
	516	out_open:
	517	kfree(msg);
3fbeccf8	518	DRM_ERROR("Failed to send host log message.\n");
f37230c0 TH	519
f37230c0 TH	520	return -EINVAL;
89da76fd	521	}
cb92a323 RS	522
	523
	524	/**
	525	* vmw_msg_ioctl: Sends and receveives a message to/from host from/to user-space
	526	*
	527	* Sends a message from user-space to host.
	528	* Can also receive a result from host and return that to user-space.
	529	*
	530	* @dev: Identifies the drm device.
	531	* @data: Pointer to the ioctl argument.
	532	* @file_priv: Identifies the caller.
	533	* Return: Zero on success, negative error code on error.
	534	*/
	535
	536	int vmw_msg_ioctl(struct drm_device dev, void data,
	537	struct drm_file *file_priv)
	538	{
	539	struct drm_vmw_msg_arg *arg =
	540	(struct drm_vmw_msg_arg *) data;
	541	struct rpc_channel channel;
	542	char *msg;
	543	int length;
	544
	545	msg = kmalloc(MAX_USER_MSG_LENGTH, GFP_KERNEL);
	546	if (!msg) {
	547	DRM_ERROR("Cannot allocate memory for log message.\n");
	548	return -ENOMEM;
	549	}
	550
	551	length = strncpy_from_user(msg, (void __user *)((unsigned long)arg->send),
	552	MAX_USER_MSG_LENGTH);
	553	if (length < 0 \|\| length >= MAX_USER_MSG_LENGTH) {
	554	DRM_ERROR("Userspace message access failure.\n");
	555	kfree(msg);
	556	return -EINVAL;
	557	}
	558
	559
	560	if (vmw_open_channel(&channel, RPCI_PROTOCOL_NUM)) {
	561	DRM_ERROR("Failed to open channel.\n");
	562	goto out_open;
	563	}
	564
	565	if (vmw_send_msg(&channel, msg)) {
	566	DRM_ERROR("Failed to send message to host.\n");
	567	goto out_msg;
	568	}
	569
	570	if (!arg->send_only) {
	571	char *reply = NULL;
	572	size_t reply_len = 0;
	573
	574	if (vmw_recv_msg(&channel, (void *) &reply, &reply_len)) {
	575	DRM_ERROR("Failed to receive message from host.\n");
	576	goto out_msg;
	577	}
	578	if (reply && reply_len > 0) {
	579	if (copy_to_user((void __user *)((unsigned long)arg->receive),
	580	reply, reply_len)) {
	581	DRM_ERROR("Failed to copy message to userspace.\n");
	582	kfree(reply);
	583	goto out_msg;
	584	}
	585	arg->receive_len = (__u32)reply_len;
586	}
587	kfree(reply);
588	}
589
590	vmw_close_channel(&channel);
591	kfree(msg);
592
593	return 0;
594
595	out_msg:
596	vmw_close_channel(&channel);
597	out_open:
598	kfree(msg);
599
600	return -EINVAL;
601	}