staging: Remove the drivers for the Unisys s-Par

The Unisys sub-tree of drivers/staging contains three drivers for the
"Unisys Secure Partition" (s-Par(R)): visorhba, visorinput, visornic.

They have no maintainers, in fact the only one that is listed in
MAINTAINERS has an unreacheable email address. During 2021 and 2022
several patches have been submitted to these drivers but nobody at
Unisys cared of reviewing the changes. Probably, also the
"sparmaintainer" internal list of unisys.com is not anymore read by
interested Unisys' engineers.

Therefore, remove the drivers/staging/unisys directory and delete the
relevant entries in the MAINTAINERS, Kconfig, Makefile files, then
remove also the drivers/visorbus directory which is not anymore needed
(it contained the driver for the virtualized bus for the Unisys s-Par
firmware).

Cc: David Kershner <david.kershner@unisys.com>
Cc: <sparmaintainer@unisys.com>
Cc: Ken Cox <jkc@redhat.com>
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Link: https://lore.kernel.org/r/20220414103217.32058-1-fmdefrancesco@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 0 insertions, 1691 deletions

diff --git a/drivers/visorbus/visorchipset.c b/drivers/visorbus/visorchipset.c
deleted file mode 100644
index 5668cad86e37..000000000000
--- a/drivers/visorbus/visorchipset.c
+++ /dev/null
@@ -1,1691 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright (C) 2010 - 2015 UNISYS CORPORATION
- * All rights reserved.
- */
-
-#include <linux/acpi.h>
-#include <linux/crash_dump.h>
-#include <linux/visorbus.h>
-
-#include "visorbus_private.h"
-
-/* {72120008-4AAB-11DC-8530-444553544200} */
-#define VISOR_SIOVM_GUID GUID_INIT(0x72120008, 0x4AAB, 0x11DC, 0x85, 0x30, \
-				   0x44, 0x45, 0x53, 0x54, 0x42, 0x00)
-
-static const guid_t visor_vhba_channel_guid = VISOR_VHBA_CHANNEL_GUID;
-static const guid_t visor_siovm_guid = VISOR_SIOVM_GUID;
-static const guid_t visor_controlvm_channel_guid = VISOR_CONTROLVM_CHANNEL_GUID;
-
-#define POLLJIFFIES_CONTROLVM_FAST 1
-#define POLLJIFFIES_CONTROLVM_SLOW 100
-
-#define MAX_CONTROLVM_PAYLOAD_BYTES (1024 * 128)
-
-#define UNISYS_VISOR_LEAF_ID 0x40000000
-
-/* The s-Par leaf ID returns "UnisysSpar64" encoded across ebx, ecx, edx */
-#define UNISYS_VISOR_ID_EBX 0x73696e55
-#define UNISYS_VISOR_ID_ECX 0x70537379
-#define UNISYS_VISOR_ID_EDX 0x34367261
-
-/*
- * When the controlvm channel is idle for at least MIN_IDLE_SECONDS, we switch
- * to slow polling mode. As soon as we get a controlvm message, we switch back
- * to fast polling mode.
- */
-#define MIN_IDLE_SECONDS 10
-
-struct parser_context {
-	unsigned long allocbytes;
-	unsigned long param_bytes;
-	u8 *curr;
-	unsigned long bytes_remaining;
-	bool byte_stream;
-	struct visor_controlvm_parameters_header data;
-};
-
-/* VMCALL_CONTROLVM_ADDR: Used by all guests, not just IO. */
-#define VMCALL_CONTROLVM_ADDR 0x0501
-
-enum vmcall_result {
-	VMCALL_RESULT_SUCCESS = 0,
-	VMCALL_RESULT_INVALID_PARAM = 1,
-	VMCALL_RESULT_DATA_UNAVAILABLE = 2,
-	VMCALL_RESULT_FAILURE_UNAVAILABLE = 3,
-	VMCALL_RESULT_DEVICE_ERROR = 4,
-	VMCALL_RESULT_DEVICE_NOT_READY = 5
-};
-
-/*
- * struct vmcall_io_controlvm_addr_params - Structure for IO VMCALLS. Has
- *					    parameters to VMCALL_CONTROLVM_ADDR
- *					    interface.
- * @address:	   The Guest-relative physical address of the ControlVm channel.
- *		   This VMCall fills this in with the appropriate address.
- *		   Contents provided by this VMCALL (OUT).
- * @channel_bytes: The size of the ControlVm channel in bytes This VMCall fills
- *		   this in with the appropriate address. Contents provided by
- *		   this VMCALL (OUT).
- * @unused:	   Unused Bytes in the 64-Bit Aligned Struct.
- */
-struct vmcall_io_controlvm_addr_params {
-	u64 address;
-	u32 channel_bytes;
-	u8 unused[4];
-} __packed;
-
-struct visorchipset_device {
-	struct acpi_device *acpi_device;
-	unsigned long poll_jiffies;
-	/* when we got our last controlvm message */
-	unsigned long most_recent_message_jiffies;
-	struct delayed_work periodic_controlvm_work;
-	struct visorchannel *controlvm_channel;
-	unsigned long controlvm_payload_bytes_buffered;
-	/*
-	 * The following variables are used to handle the scenario where we are
-	 * unable to offload the payload from a controlvm message due to memory
-	 * requirements. In this scenario, we simply stash the controlvm
-	 * message, then attempt to process it again the next time
-	 * controlvm_periodic_work() runs.
-	 */
-	struct controlvm_message controlvm_pending_msg;
-	bool controlvm_pending_msg_valid;
-	struct vmcall_io_controlvm_addr_params controlvm_params;
-};
-
-static struct visorchipset_device *chipset_dev;
-
-struct parahotplug_request {
-	struct list_head list;
-	int id;
-	unsigned long expiration;
-	struct controlvm_message msg;
-};
-
-/* prototypes for attributes */
-static ssize_t toolaction_show(struct device *dev,
-			       struct device_attribute *attr,
-			       char *buf)
-{
-	u8 tool_action = 0;
-	int err;
-
-	err = visorchannel_read(chipset_dev->controlvm_channel,
-				offsetof(struct visor_controlvm_channel,
-					 tool_action),
-				&tool_action, sizeof(u8));
-	if (err)
-		return err;
-	return sprintf(buf, "%u\n", tool_action);
-}
-
-static ssize_t toolaction_store(struct device *dev,
-				struct device_attribute *attr,
-				const char *buf, size_t count)
-{
-	u8 tool_action;
-	int err;
-
-	if (kstrtou8(buf, 10, &tool_action))
-		return -EINVAL;
-	err = visorchannel_write(chipset_dev->controlvm_channel,
-				 offsetof(struct visor_controlvm_channel,
-					  tool_action),
-				 &tool_action, sizeof(u8));
-	if (err)
-		return err;
-	return count;
-}
-static DEVICE_ATTR_RW(toolaction);
-
-static ssize_t boottotool_show(struct device *dev,
-			       struct device_attribute *attr,
-			       char *buf)
-{
-	struct efi_visor_indication efi_visor_indication;
-	int err;
-
-	err = visorchannel_read(chipset_dev->controlvm_channel,
-				offsetof(struct visor_controlvm_channel,
-					 efi_visor_ind),
-				&efi_visor_indication,
-				sizeof(struct efi_visor_indication));
-	if (err)
-		return err;
-	return sprintf(buf, "%u\n", efi_visor_indication.boot_to_tool);
-}
-
-static ssize_t boottotool_store(struct device *dev,
-				struct device_attribute *attr,
-				const char *buf, size_t count)
-{
-	int val, err;
-	struct efi_visor_indication efi_visor_indication;
-
-	if (kstrtoint(buf, 10, &val))
-		return -EINVAL;
-	efi_visor_indication.boot_to_tool = val;
-	err = visorchannel_write(chipset_dev->controlvm_channel,
-				 offsetof(struct visor_controlvm_channel,
-					  efi_visor_ind),
-				 &(efi_visor_indication),
-				 sizeof(struct efi_visor_indication));
-	if (err)
-		return err;
-	return count;
-}
-static DEVICE_ATTR_RW(boottotool);
-
-static ssize_t error_show(struct device *dev, struct device_attribute *attr,
-			  char *buf)
-{
-	u32 error = 0;
-	int err;
-
-	err = visorchannel_read(chipset_dev->controlvm_channel,
-				offsetof(struct visor_controlvm_channel,
-					 installation_error),
-				&error, sizeof(u32));
-	if (err)
-		return err;
-	return sprintf(buf, "%u\n", error);
-}
-
-static ssize_t error_store(struct device *dev, struct device_attribute *attr,
-			   const char *buf, size_t count)
-{
-	u32 error;
-	int err;
-
-	if (kstrtou32(buf, 10, &error))
-		return -EINVAL;
-	err = visorchannel_write(chipset_dev->controlvm_channel,
-				 offsetof(struct visor_controlvm_channel,
-					  installation_error),
-				 &error, sizeof(u32));
-	if (err)
-		return err;
-	return count;
-}
-static DEVICE_ATTR_RW(error);
-
-static ssize_t textid_show(struct device *dev, struct device_attribute *attr,
-			   char *buf)
-{
-	u32 text_id = 0;
-	int err;
-
-	err = visorchannel_read(chipset_dev->controlvm_channel,
-				offsetof(struct visor_controlvm_channel,
-					 installation_text_id),
-				&text_id, sizeof(u32));
-	if (err)
-		return err;
-	return sprintf(buf, "%u\n", text_id);
-}
-
-static ssize_t textid_store(struct device *dev, struct device_attribute *attr,
-			    const char *buf, size_t count)
-{
-	u32 text_id;
-	int err;
-
-	if (kstrtou32(buf, 10, &text_id))
-		return -EINVAL;
-	err = visorchannel_write(chipset_dev->controlvm_channel,
-				 offsetof(struct visor_controlvm_channel,
-					  installation_text_id),
-				 &text_id, sizeof(u32));
-	if (err)
-		return err;
-	return count;
-}
-static DEVICE_ATTR_RW(textid);
-
-static ssize_t remaining_steps_show(struct device *dev,
-				    struct device_attribute *attr, char *buf)
-{
-	u16 remaining_steps = 0;
-	int err;
-
-	err = visorchannel_read(chipset_dev->controlvm_channel,
-				offsetof(struct visor_controlvm_channel,
-					 installation_remaining_steps),
-				&remaining_steps, sizeof(u16));
-	if (err)
-		return err;
-	return sprintf(buf, "%hu\n", remaining_steps);
-}
-
-static ssize_t remaining_steps_store(struct device *dev,
-				     struct device_attribute *attr,
-				     const char *buf, size_t count)
-{
-	u16 remaining_steps;
-	int err;
-
-	if (kstrtou16(buf, 10, &remaining_steps))
-		return -EINVAL;
-	err = visorchannel_write(chipset_dev->controlvm_channel,
-				 offsetof(struct visor_controlvm_channel,
-					  installation_remaining_steps),
-				 &remaining_steps, sizeof(u16));
-	if (err)
-		return err;
-	return count;
-}
-static DEVICE_ATTR_RW(remaining_steps);
-
-static void controlvm_init_response(struct controlvm_message *msg,
-				    struct controlvm_message_header *msg_hdr,
-				    int response)
-{
-	memset(msg, 0, sizeof(struct controlvm_message));
-	memcpy(&msg->hdr, msg_hdr, sizeof(struct controlvm_message_header));
-	msg->hdr.payload_bytes = 0;
-	msg->hdr.payload_vm_offset = 0;
-	msg->hdr.payload_max_bytes = 0;
-	if (response < 0) {
-		msg->hdr.flags.failed = 1;
-		msg->hdr.completion_status = (u32)(-response);
-	}
-}
-
-static int controlvm_respond_chipset_init(
-				struct controlvm_message_header *msg_hdr,
-				int response,
-				enum visor_chipset_feature features)
-{
-	struct controlvm_message outmsg;
-
-	controlvm_init_response(&outmsg, msg_hdr, response);
-	outmsg.cmd.init_chipset.features = features;
-	return visorchannel_signalinsert(chipset_dev->controlvm_channel,
-					 CONTROLVM_QUEUE_REQUEST, &outmsg);
-}
-
-static int chipset_init(struct controlvm_message *inmsg)
-{
-	static int chipset_inited;
-	enum visor_chipset_feature features = 0;
-	int rc = CONTROLVM_RESP_SUCCESS;
-	int res = 0;
-
-	if (chipset_inited) {
-		rc = -CONTROLVM_RESP_ALREADY_DONE;
-		res = -EIO;
-		goto out_respond;
-	}
-	chipset_inited = 1;
-	/*
-	 * Set features to indicate we support parahotplug (if Command also
-	 * supports it). Set the "reply" bit so Command knows this is a
-	 * features-aware driver.
-	 */
-	features = inmsg->cmd.init_chipset.features &
-		   VISOR_CHIPSET_FEATURE_PARA_HOTPLUG;
-	features |= VISOR_CHIPSET_FEATURE_REPLY;
-
-out_respond:
-	if (inmsg->hdr.flags.response_expected)
-		res = controlvm_respond_chipset_init(&inmsg->hdr, rc, features);
-
-	return res;
-}
-
-static int controlvm_respond(struct controlvm_message_header *msg_hdr,
-			     int response, struct visor_segment_state *state)
-{
-	struct controlvm_message outmsg;
-
-	controlvm_init_response(&outmsg, msg_hdr, response);
-	if (outmsg.hdr.flags.test_message == 1)
-		return -EINVAL;
-	if (state) {
-		outmsg.cmd.device_change_state.state = *state;
-		outmsg.cmd.device_change_state.flags.phys_device = 1;
-	}
-	return visorchannel_signalinsert(chipset_dev->controlvm_channel,
-					 CONTROLVM_QUEUE_REQUEST, &outmsg);
-}
-
-enum crash_obj_type {
-	CRASH_DEV,
-	CRASH_BUS,
-};
-
-static int save_crash_message(struct controlvm_message *msg,
-			      enum crash_obj_type cr_type)
-{
-	u32 local_crash_msg_offset;
-	u16 local_crash_msg_count;
-	int err;
-
-	err = visorchannel_read(chipset_dev->controlvm_channel,
-				offsetof(struct visor_controlvm_channel,
-					 saved_crash_message_count),
-				&local_crash_msg_count, sizeof(u16));
-	if (err) {
-		dev_err(&chipset_dev->acpi_device->dev,
-			"failed to read message count\n");
-		return err;
-	}
-	if (local_crash_msg_count != CONTROLVM_CRASHMSG_MAX) {
-		dev_err(&chipset_dev->acpi_device->dev,
-			"invalid number of messages\n");
-		return -EIO;
-	}
-	err = visorchannel_read(chipset_dev->controlvm_channel,
-				offsetof(struct visor_controlvm_channel,
-					 saved_crash_message_offset),
-				&local_crash_msg_offset, sizeof(u32));
-	if (err) {
-		dev_err(&chipset_dev->acpi_device->dev,
-			"failed to read offset\n");
-		return err;
-	}
-	switch (cr_type) {
-	case CRASH_DEV:
-		local_crash_msg_offset += sizeof(struct controlvm_message);
-		err = visorchannel_write(chipset_dev->controlvm_channel,
-					 local_crash_msg_offset, msg,
-					 sizeof(struct controlvm_message));
-		if (err) {
-			dev_err(&chipset_dev->acpi_device->dev,
-				"failed to write dev msg\n");
-			return err;
-		}
-		break;
-	case CRASH_BUS:
-		err = visorchannel_write(chipset_dev->controlvm_channel,
-					 local_crash_msg_offset, msg,
-					 sizeof(struct controlvm_message));
-		if (err) {
-			dev_err(&chipset_dev->acpi_device->dev,
-				"failed to write bus msg\n");
-			return err;
-		}
-		break;
-	default:
-		dev_err(&chipset_dev->acpi_device->dev,
-			"Invalid crash_obj_type\n");
-		break;
-	}
-	return 0;
-}
-
-static int controlvm_responder(enum controlvm_id cmd_id,
-			       struct controlvm_message_header *pending_msg_hdr,
-			       int response)
-{
-	if (pending_msg_hdr->id != (u32)cmd_id)
-		return -EINVAL;
-
-	return controlvm_respond(pending_msg_hdr, response, NULL);
-}
-
-static int device_changestate_responder(enum controlvm_id cmd_id,
-					struct visor_device *p, int response,
-					struct visor_segment_state state)
-{
-	struct controlvm_message outmsg;
-
-	if (p->pending_msg_hdr->id != cmd_id)
-		return -EINVAL;
-
-	controlvm_init_response(&outmsg, p->pending_msg_hdr, response);
-	outmsg.cmd.device_change_state.bus_no = p->chipset_bus_no;
-	outmsg.cmd.device_change_state.dev_no = p->chipset_dev_no;
-	outmsg.cmd.device_change_state.state = state;
-	return visorchannel_signalinsert(chipset_dev->controlvm_channel,
-					 CONTROLVM_QUEUE_REQUEST, &outmsg);
-}
-
-static int visorbus_create(struct controlvm_message *inmsg)
-{
-	struct controlvm_message_packet *cmd = &inmsg->cmd;
-	struct controlvm_message_header *pmsg_hdr;
-	u32 bus_no = cmd->create_bus.bus_no;
-	struct visor_device *bus_info;
-	struct visorchannel *visorchannel;
-	int err;
-
-	bus_info = visorbus_get_device_by_id(bus_no, BUS_ROOT_DEVICE, NULL);
-	if (bus_info && bus_info->state.created == 1) {
-		dev_err(&chipset_dev->acpi_device->dev,
-			"failed %s: already exists\n", __func__);
-		err = -EEXIST;
-		goto err_respond;
-	}
-	bus_info = kzalloc(sizeof(*bus_info), GFP_KERNEL);
-	if (!bus_info) {
-		err = -ENOMEM;
-		goto err_respond;
-	}
-	INIT_LIST_HEAD(&bus_info->list_all);
-	bus_info->chipset_bus_no = bus_no;
-	bus_info->chipset_dev_no = BUS_ROOT_DEVICE;
-	if (guid_equal(&cmd->create_bus.bus_inst_guid, &visor_siovm_guid)) {
-		err = save_crash_message(inmsg, CRASH_BUS);
-		if (err)
-			goto err_free_bus_info;
-	}
-	if (inmsg->hdr.flags.response_expected == 1) {
-		pmsg_hdr = kzalloc(sizeof(*pmsg_hdr), GFP_KERNEL);
-		if (!pmsg_hdr) {
-			err = -ENOMEM;
-			goto err_free_bus_info;
-		}
-		memcpy(pmsg_hdr, &inmsg->hdr,
-		       sizeof(struct controlvm_message_header));
-		bus_info->pending_msg_hdr = pmsg_hdr;
-	}
-	visorchannel = visorchannel_create(cmd->create_bus.channel_addr,
-					   GFP_KERNEL,
-					   &cmd->create_bus.bus_data_type_guid,
-					   false);
-	if (!visorchannel) {
-		err = -ENOMEM;
-		goto err_free_pending_msg;
-	}
-	bus_info->visorchannel = visorchannel;
-	/* Response will be handled by visorbus_create_instance on success */
-	err = visorbus_create_instance(bus_info);
-	if (err)
-		goto err_destroy_channel;
-	return 0;
-
-err_destroy_channel:
-	visorchannel_destroy(visorchannel);
-
-err_free_pending_msg:
-	kfree(bus_info->pending_msg_hdr);
-
-err_free_bus_info:
-	kfree(bus_info);
-
-err_respond:
-	if (inmsg->hdr.flags.response_expected == 1)
-		controlvm_responder(inmsg->hdr.id, &inmsg->hdr, err);
-	return err;
-}
-
-static int visorbus_destroy(struct controlvm_message *inmsg)
-{
-	struct controlvm_message_header *pmsg_hdr;
-	u32 bus_no = inmsg->cmd.destroy_bus.bus_no;
-	struct visor_device *bus_info;
-	int err;
-
-	bus_info = visorbus_get_device_by_id(bus_no, BUS_ROOT_DEVICE, NULL);
-	if (!bus_info) {
-		err = -ENODEV;
-		goto err_respond;
-	}
-	if (bus_info->state.created == 0) {
-		err = -ENOENT;
-		goto err_respond;
-	}
-	if (bus_info->pending_msg_hdr) {
-		/* only non-NULL if dev is still waiting on a response */
-		err = -EEXIST;
-		goto err_respond;
-	}
-	if (inmsg->hdr.flags.response_expected == 1) {
-		pmsg_hdr = kzalloc(sizeof(*pmsg_hdr), GFP_KERNEL);
-		if (!pmsg_hdr) {
-			err = -ENOMEM;
-			goto err_respond;
-		}
-		memcpy(pmsg_hdr, &inmsg->hdr,
-		       sizeof(struct controlvm_message_header));
-		bus_info->pending_msg_hdr = pmsg_hdr;
-	}
-	/* Response will be handled by visorbus_remove_instance */
-	visorbus_remove_instance(bus_info);
-	return 0;
-
-err_respond:
-	if (inmsg->hdr.flags.response_expected == 1)
-		controlvm_responder(inmsg->hdr.id, &inmsg->hdr, err);
-	return err;
-}
-
-static const guid_t *parser_id_get(struct parser_context *ctx)
-{
-	return &ctx->data.id;
-}
-
-static void *parser_string_get(u8 *pscan, int nscan)
-{
-	int value_length;
-	void *value;
-
-	if (nscan == 0)
-		return NULL;
-
-	value_length = strnlen(pscan, nscan);
-	value = kzalloc(value_length + 1, GFP_KERNEL);
-	if (!value)
-		return NULL;
-	if (value_length > 0)
-		memcpy(value, pscan, value_length);
-	return value;
-}
-
-static void *parser_name_get(struct parser_context *ctx)
-{
-	struct visor_controlvm_parameters_header *phdr;
-
-	phdr = &ctx->data;
-	if ((unsigned long)phdr->name_offset +
-	    (unsigned long)phdr->name_length > ctx->param_bytes)
-		return NULL;
-	ctx->curr = (char *)&phdr + phdr->name_offset;
-	ctx->bytes_remaining = phdr->name_length;
-	return parser_string_get(ctx->curr, phdr->name_length);
-}
-
-static int visorbus_configure(struct controlvm_message *inmsg,
-			      struct parser_context *parser_ctx)
-{
-	struct controlvm_message_packet *cmd = &inmsg->cmd;
-	u32 bus_no;
-	struct visor_device *bus_info;
-	int err = 0;
-
-	bus_no = cmd->configure_bus.bus_no;
-	bus_info = visorbus_get_device_by_id(bus_no, BUS_ROOT_DEVICE, NULL);
-	if (!bus_info) {
-		err = -EINVAL;
-		goto err_respond;
-	}
-	if (bus_info->state.created == 0) {
-		err = -EINVAL;
-		goto err_respond;
-	}
-	if (bus_info->pending_msg_hdr) {
-		err = -EIO;
-		goto err_respond;
-	}
-	err = visorchannel_set_clientpartition(bus_info->visorchannel,
-					       cmd->configure_bus.guest_handle);
-	if (err)
-		goto err_respond;
-	if (parser_ctx) {
-		const guid_t *partition_guid = parser_id_get(parser_ctx);
-
-		guid_copy(&bus_info->partition_guid, partition_guid);
-		bus_info->name = parser_name_get(parser_ctx);
-	}
-	if (inmsg->hdr.flags.response_expected == 1)
-		controlvm_responder(inmsg->hdr.id, &inmsg->hdr, err);
-	return 0;
-
-err_respond:
-	dev_err(&chipset_dev->acpi_device->dev,
-		"%s exited with err: %d\n", __func__, err);
-	if (inmsg->hdr.flags.response_expected == 1)
-		controlvm_responder(inmsg->hdr.id, &inmsg->hdr, err);
-	return err;
-}
-
-static int visorbus_device_create(struct controlvm_message *inmsg)
-{
-	struct controlvm_message_packet *cmd = &inmsg->cmd;
-	struct controlvm_message_header *pmsg_hdr;
-	u32 bus_no = cmd->create_device.bus_no;
-	u32 dev_no = cmd->create_device.dev_no;
-	struct visor_device *dev_info;
-	struct visor_device *bus_info;
-	struct visorchannel *visorchannel;
-	int err;
-
-	bus_info = visorbus_get_device_by_id(bus_no, BUS_ROOT_DEVICE, NULL);
-	if (!bus_info) {
-		dev_err(&chipset_dev->acpi_device->dev,
-			"failed to get bus by id: %d\n", bus_no);
-		err = -ENODEV;
-		goto err_respond;
-	}
-	if (bus_info->state.created == 0) {
-		dev_err(&chipset_dev->acpi_device->dev,
-			"bus not created, id: %d\n", bus_no);
-		err = -EINVAL;
-		goto err_respond;
-	}
-	dev_info = visorbus_get_device_by_id(bus_no, dev_no, NULL);
-	if (dev_info && dev_info->state.created == 1) {
-		dev_err(&chipset_dev->acpi_device->dev,
-			"failed to get bus by id: %d/%d\n", bus_no, dev_no);
-		err = -EEXIST;
-		goto err_respond;
-	}
-
-	dev_info = kzalloc(sizeof(*dev_info), GFP_KERNEL);
-	if (!dev_info) {
-		err = -ENOMEM;
-		goto err_respond;
-	}
-	dev_info->chipset_bus_no = bus_no;
-	dev_info->chipset_dev_no = dev_no;
-	guid_copy(&dev_info->inst, &cmd->create_device.dev_inst_guid);
-	dev_info->device.parent = &bus_info->device;
-	visorchannel = visorchannel_create(cmd->create_device.channel_addr,
-					   GFP_KERNEL,
-					   &cmd->create_device.data_type_guid,
-					   true);
-	if (!visorchannel) {
-		dev_err(&chipset_dev->acpi_device->dev,
-			"failed to create visorchannel: %d/%d\n",
-			bus_no, dev_no);
-		err = -ENOMEM;
-		goto err_free_dev_info;
-	}
-	dev_info->visorchannel = visorchannel;
-	guid_copy(&dev_info->channel_type_guid,
-		  &cmd->create_device.data_type_guid);
-	if (guid_equal(&cmd->create_device.data_type_guid,
-		       &visor_vhba_channel_guid)) {
-		err = save_crash_message(inmsg, CRASH_DEV);
-		if (err)
-			goto err_destroy_visorchannel;
-	}
-	if (inmsg->hdr.flags.response_expected == 1) {
-		pmsg_hdr = kzalloc(sizeof(*pmsg_hdr), GFP_KERNEL);
-		if (!pmsg_hdr) {
-			err = -ENOMEM;
-			goto err_destroy_visorchannel;
-		}
-		memcpy(pmsg_hdr, &inmsg->hdr,
-		       sizeof(struct controlvm_message_header));
-		dev_info->pending_msg_hdr = pmsg_hdr;
-	}
-	/* create_visor_device will send response */
-	err = create_visor_device(dev_info);
-	if (err)
-		goto err_destroy_visorchannel;
-
-	return 0;
-
-err_destroy_visorchannel:
-	visorchannel_destroy(visorchannel);
-
-err_free_dev_info:
-	kfree(dev_info);
-
-err_respond:
-	if (inmsg->hdr.flags.response_expected == 1)
-		controlvm_responder(inmsg->hdr.id, &inmsg->hdr, err);
-	return err;
-}
-
-static int visorbus_device_changestate(struct controlvm_message *inmsg)
-{
-	struct controlvm_message_packet *cmd = &inmsg->cmd;
-	struct controlvm_message_header *pmsg_hdr;
-	u32 bus_no = cmd->device_change_state.bus_no;
-	u32 dev_no = cmd->device_change_state.dev_no;
-	struct visor_segment_state state = cmd->device_change_state.state;
-	struct visor_device *dev_info;
-	int err = 0;
-
-	dev_info = visorbus_get_device_by_id(bus_no, dev_no, NULL);
-	if (!dev_info) {
-		err = -ENODEV;
-		goto err_respond;
-	}
-	if (dev_info->state.created == 0) {
-		err = -EINVAL;
-		goto err_respond;
-	}
-	if (dev_info->pending_msg_hdr) {
-		/* only non-NULL if dev is still waiting on a response */
-		err = -EIO;
-		goto err_respond;
-	}
-
-	if (inmsg->hdr.flags.response_expected == 1) {
-		pmsg_hdr = kzalloc(sizeof(*pmsg_hdr), GFP_KERNEL);
-		if (!pmsg_hdr) {
-			err = -ENOMEM;
-			goto err_respond;
-		}
-		memcpy(pmsg_hdr, &inmsg->hdr,
-		       sizeof(struct controlvm_message_header));
-		dev_info->pending_msg_hdr = pmsg_hdr;
-	}
-	if (state.alive == segment_state_running.alive &&
-	    state.operating == segment_state_running.operating)
-		/* Response will be sent from visorchipset_device_resume */
-		err = visorchipset_device_resume(dev_info);
-	/* ServerNotReady / ServerLost / SegmentStateStandby */
-	else if (state.alive == segment_state_standby.alive &&
-		 state.operating == segment_state_standby.operating)
-		/*
-		 * technically this is standby case where server is lost.
-		 * Response will be sent from visorchipset_device_pause.
-		 */
-		err = visorchipset_device_pause(dev_info);
-	if (err)
-		goto err_respond;
-	return 0;
-
-err_respond:
-	dev_err(&chipset_dev->acpi_device->dev, "failed: %d\n", err);
-	if (inmsg->hdr.flags.response_expected == 1)
-		controlvm_responder(inmsg->hdr.id, &inmsg->hdr, err);
-	return err;
-}
-
-static int visorbus_device_destroy(struct controlvm_message *inmsg)
-{
-	struct controlvm_message_packet *cmd = &inmsg->cmd;
-	struct controlvm_message_header *pmsg_hdr;
-	u32 bus_no = cmd->destroy_device.bus_no;
-	u32 dev_no = cmd->destroy_device.dev_no;
-	struct visor_device *dev_info;
-	int err;
-
-	dev_info = visorbus_get_device_by_id(bus_no, dev_no, NULL);
-	if (!dev_info) {
-		err = -ENODEV;
-		goto err_respond;
-	}
-	if (dev_info->state.created == 0) {
-		err = -EINVAL;
-		goto err_respond;
-	}
-	if (dev_info->pending_msg_hdr) {
-		/* only non-NULL if dev is still waiting on a response */
-		err = -EIO;
-		goto err_respond;
-	}
-	if (inmsg->hdr.flags.response_expected == 1) {
-		pmsg_hdr = kzalloc(sizeof(*pmsg_hdr), GFP_KERNEL);
-		if (!pmsg_hdr) {
-			err = -ENOMEM;
-			goto err_respond;
-		}
-
-		memcpy(pmsg_hdr, &inmsg->hdr,
-		       sizeof(struct controlvm_message_header));
-		dev_info->pending_msg_hdr = pmsg_hdr;
-	}
-	kfree(dev_info->name);
-	remove_visor_device(dev_info);
-	return 0;
-
-err_respond:
-	if (inmsg->hdr.flags.response_expected == 1)
-		controlvm_responder(inmsg->hdr.id, &inmsg->hdr, err);
-	return err;
-}
-
-/*
- * The general parahotplug flow works as follows. The visorchipset receives
- * a DEVICE_CHANGESTATE message from Command specifying a physical device
- * to enable or disable. The CONTROLVM message handler calls
- * parahotplug_process_message, which then adds the message to a global list
- * and kicks off a udev event which causes a user level script to enable or
- * disable the specified device. The udev script then writes to
- * /sys/devices/platform/visorchipset/parahotplug, which causes the
- * parahotplug store functions to get called, at which point the
- * appropriate CONTROLVM message is retrieved from the list and responded to.
- */
-
-#define PARAHOTPLUG_TIMEOUT_MS 2000
-
-/*
- * parahotplug_next_id() - generate unique int to match an outstanding
- *                         CONTROLVM message with a udev script /sys
- *                         response
- *
- * Return: a unique integer value
- */
-static int parahotplug_next_id(void)
-{
-	static atomic_t id = ATOMIC_INIT(0);
-
-	return atomic_inc_return(&id);
-}
-
-/*
- * parahotplug_next_expiration() - returns the time (in jiffies) when a
- *                                 CONTROLVM message on the list should expire
- *                                 -- PARAHOTPLUG_TIMEOUT_MS in the future
- *
- * Return: expected expiration time (in jiffies)
- */
-static unsigned long parahotplug_next_expiration(void)
-{
-	return jiffies + msecs_to_jiffies(PARAHOTPLUG_TIMEOUT_MS);
-}
-
-/*
- * parahotplug_request_create() - create a parahotplug_request, which is
- *                                basically a wrapper for a CONTROLVM_MESSAGE
- *                                that we can stick on a list
- * @msg: the message to insert in the request
- *
- * Return: the request containing the provided message
- */
-static struct parahotplug_request *parahotplug_request_create(
-						struct controlvm_message *msg)
-{
-	struct parahotplug_request *req;
-
-	req = kmalloc(sizeof(*req), GFP_KERNEL);
-	if (!req)
-		return NULL;
-	req->id = parahotplug_next_id();
-	req->expiration = parahotplug_next_expiration();
-	req->msg = *msg;
-	return req;
-}
-
-/*
- * parahotplug_request_destroy() - free a parahotplug_request
- * @req: the request to deallocate
- */
-static void parahotplug_request_destroy(struct parahotplug_request *req)
-{
-	kfree(req);
-}
-
-static LIST_HEAD(parahotplug_request_list);
-/* lock for above */
-static DEFINE_SPINLOCK(parahotplug_request_list_lock);
-
-/*
- * parahotplug_request_complete() - mark request as complete
- * @id:     the id of the request
- * @active: indicates whether the request is assigned to active partition
- *
- * Called from the /sys handler, which means the user script has
- * finished the enable/disable. Find the matching identifier, and
- * respond to the CONTROLVM message with success.
- *
- * Return: 0 on success or -EINVAL on failure
- */
-static int parahotplug_request_complete(int id, u16 active)
-{
-	struct list_head *pos;
-	struct list_head *tmp;
-	struct parahotplug_request *req;
-
-	spin_lock(&parahotplug_request_list_lock);
-	/* Look for a request matching "id". */
-	list_for_each_safe(pos, tmp, &parahotplug_request_list) {
-		req = list_entry(pos, struct parahotplug_request, list);
-		if (req->id == id) {
-			/*
-			 * Found a match. Remove it from the list and
-			 * respond.
-			 */
-			list_del(pos);
-			spin_unlock(&parahotplug_request_list_lock);
-			req->msg.cmd.device_change_state.state.active = active;
-			if (req->msg.hdr.flags.response_expected)
-				controlvm_respond(
-				       &req->msg.hdr, CONTROLVM_RESP_SUCCESS,
-				       &req->msg.cmd.device_change_state.state);
-			parahotplug_request_destroy(req);
-			return 0;
-		}
-	}
-	spin_unlock(&parahotplug_request_list_lock);
-	return -EINVAL;
-}
-
-/*
- * devicedisabled_store() - disables the hotplug device
- * @dev:   sysfs interface variable not utilized in this function
- * @attr:  sysfs interface variable not utilized in this function
- * @buf:   buffer containing the device id
- * @count: the size of the buffer
- *
- * The parahotplug/devicedisabled interface gets called by our support script
- * when an SR-IOV device has been shut down. The ID is passed to the script
- * and then passed back when the device has been removed.
- *
- * Return: the size of the buffer for success or negative for error
- */
-static ssize_t devicedisabled_store(struct device *dev,
-				    struct device_attribute *attr,
-				    const char *buf, size_t count)
-{
-	unsigned int id;
-	int err;
-
-	if (kstrtouint(buf, 10, &id))
-		return -EINVAL;
-	err = parahotplug_request_complete(id, 0);
-	if (err < 0)
-		return err;
-	return count;
-}
-static DEVICE_ATTR_WO(devicedisabled);
-
-/*
- * deviceenabled_store() - enables the hotplug device
- * @dev:   sysfs interface variable not utilized in this function
- * @attr:  sysfs interface variable not utilized in this function
- * @buf:   buffer containing the device id
- * @count: the size of the buffer
- *
- * The parahotplug/deviceenabled interface gets called by our support script
- * when an SR-IOV device has been recovered. The ID is passed to the script
- * and then passed back when the device has been brought back up.
- *
- * Return: the size of the buffer for success or negative for error
- */
-static ssize_t deviceenabled_store(struct device *dev,
-				   struct device_attribute *attr,
-				   const char *buf, size_t count)
-{
-	unsigned int id;
-
-	if (kstrtouint(buf, 10, &id))
-		return -EINVAL;
-	parahotplug_request_complete(id, 1);
-	return count;
-}
-static DEVICE_ATTR_WO(deviceenabled);
-
-static struct attribute *visorchipset_install_attrs[] = {
-	&dev_attr_toolaction.attr,
-	&dev_attr_boottotool.attr,
-	&dev_attr_error.attr,
-	&dev_attr_textid.attr,
-	&dev_attr_remaining_steps.attr,
-	NULL
-};
-
-static const struct attribute_group visorchipset_install_group = {
-	.name = "install",
-	.attrs = visorchipset_install_attrs
-};
-
-static struct attribute *visorchipset_parahotplug_attrs[] = {
-	&dev_attr_devicedisabled.attr,
-	&dev_attr_deviceenabled.attr,
-	NULL
-};
-
-static const struct attribute_group visorchipset_parahotplug_group = {
-	.name = "parahotplug",
-	.attrs = visorchipset_parahotplug_attrs
-};
-
-static const struct attribute_group *visorchipset_dev_groups[] = {
-	&visorchipset_install_group,
-	&visorchipset_parahotplug_group,
-	NULL
-};
-
-/*
- * parahotplug_request_kickoff() - initiate parahotplug request
- * @req: the request to initiate
- *
- * Cause uevent to run the user level script to do the disable/enable specified
- * in the parahotplug_request.
- */
-static int parahotplug_request_kickoff(struct parahotplug_request *req)
-{
-	struct controlvm_message_packet *cmd = &req->msg.cmd;
-	char env_cmd[40], env_id[40], env_state[40], env_bus[40], env_dev[40],
-	     env_func[40];
-	char *envp[] = { env_cmd, env_id, env_state, env_bus, env_dev,
-			 env_func, NULL
-	};
-
-	sprintf(env_cmd, "VISOR_PARAHOTPLUG=1");
-	sprintf(env_id, "VISOR_PARAHOTPLUG_ID=%d", req->id);
-	sprintf(env_state, "VISOR_PARAHOTPLUG_STATE=%d",
-		cmd->device_change_state.state.active);
-	sprintf(env_bus, "VISOR_PARAHOTPLUG_BUS=%d",
-		cmd->device_change_state.bus_no);
-	sprintf(env_dev, "VISOR_PARAHOTPLUG_DEVICE=%d",
-		cmd->device_change_state.dev_no >> 3);
-	sprintf(env_func, "VISOR_PARAHOTPLUG_FUNCTION=%d",
-		cmd->device_change_state.dev_no & 0x7);
-	return kobject_uevent_env(&chipset_dev->acpi_device->dev.kobj,
-				  KOBJ_CHANGE, envp);
-}
-
-/*
- * parahotplug_process_message() - enables or disables a PCI device by kicking
- *                                 off a udev script
- * @inmsg: the message indicating whether to enable or disable
- */
-static int parahotplug_process_message(struct controlvm_message *inmsg)
-{
-	struct parahotplug_request *req;
-	int err;
-
-	req = parahotplug_request_create(inmsg);
-	if (!req)
-		return -ENOMEM;
-	/*
-	 * For enable messages, just respond with success right away, we don't
-	 * need to wait to see if the enable was successful.
-	 */
-	if (inmsg->cmd.device_change_state.state.active) {
-		err = parahotplug_request_kickoff(req);
-		if (err)
-			goto err_respond;
-		controlvm_respond(&inmsg->hdr, CONTROLVM_RESP_SUCCESS,
-				  &inmsg->cmd.device_change_state.state);
-		parahotplug_request_destroy(req);
-		return 0;
-	}
-	/*
-	 * For disable messages, add the request to the request list before
-	 * kicking off the udev script. It won't get responded to until the
-	 * script has indicated it's done.
-	 */
-	spin_lock(&parahotplug_request_list_lock);
-	list_add_tail(&req->list, &parahotplug_request_list);
-	spin_unlock(&parahotplug_request_list_lock);
-	err = parahotplug_request_kickoff(req);
-	if (err)
-		goto err_respond;
-	return 0;
-
-err_respond:
-	controlvm_respond(&inmsg->hdr, err,
-			  &inmsg->cmd.device_change_state.state);
-	return err;
-}
-
-/*
- * chipset_ready_uevent() - sends chipset_ready action
- *
- * Send ACTION=online for DEVPATH=/sys/devices/platform/visorchipset.
- *
- * Return: 0 on success, negative on failure
- */
-static int chipset_ready_uevent(struct controlvm_message_header *msg_hdr)
-{
-	int res;
-
-	res = kobject_uevent(&chipset_dev->acpi_device->dev.kobj, KOBJ_ONLINE);
-	if (msg_hdr->flags.response_expected)
-		controlvm_respond(msg_hdr, res, NULL);
-	return res;
-}
-
-/*
- * chipset_selftest_uevent() - sends chipset_selftest action
- *
- * Send ACTION=online for DEVPATH=/sys/devices/platform/visorchipset.
- *
- * Return: 0 on success, negative on failure
- */
-static int chipset_selftest_uevent(struct controlvm_message_header *msg_hdr)
-{
-	char env_selftest[20];
-	char *envp[] = { env_selftest, NULL };
-	int res;
-
-	sprintf(env_selftest, "SPARSP_SELFTEST=%d", 1);
-	res = kobject_uevent_env(&chipset_dev->acpi_device->dev.kobj,
-				 KOBJ_CHANGE, envp);
-	if (msg_hdr->flags.response_expected)
-		controlvm_respond(msg_hdr, res, NULL);
-	return res;
-}
-
-/*
- * chipset_notready_uevent() - sends chipset_notready action
- *
- * Send ACTION=offline for DEVPATH=/sys/devices/platform/visorchipset.
- *
- * Return: 0 on success, negative on failure
- */
-static int chipset_notready_uevent(struct controlvm_message_header *msg_hdr)
-{
-	int res = kobject_uevent(&chipset_dev->acpi_device->dev.kobj,
-				 KOBJ_OFFLINE);
-
-	if (msg_hdr->flags.response_expected)
-		controlvm_respond(msg_hdr, res, NULL);
-	return res;
-}
-
-static int unisys_vmcall(unsigned long tuple, unsigned long param)
-{
-	int result = 0;
-	unsigned int cpuid_eax, cpuid_ebx, cpuid_ecx, cpuid_edx;
-	unsigned long reg_ebx;
-	unsigned long reg_ecx;
-
-	reg_ebx = param & 0xFFFFFFFF;
-	reg_ecx = param >> 32;
-	cpuid(0x00000001, &cpuid_eax, &cpuid_ebx, &cpuid_ecx, &cpuid_edx);
-	if (!(cpuid_ecx & 0x80000000))
-		return -EPERM;
-	__asm__ __volatile__(".byte 0x00f, 0x001, 0x0c1" : "=a"(result) :
-			     "a"(tuple), "b"(reg_ebx), "c"(reg_ecx));
-	if (result)
-		goto error;
-	return 0;
-
-/* Need to convert from VMCALL error codes to Linux */
-error:
-	switch (result) {
-	case VMCALL_RESULT_INVALID_PARAM:
-		return -EINVAL;
-	case VMCALL_RESULT_DATA_UNAVAILABLE:
-		return -ENODEV;
-	default:
-		return -EFAULT;
-	}
-}
-
-static int controlvm_channel_create(struct visorchipset_device *dev)
-{
-	struct visorchannel *chan;
-	u64 addr;
-	int err;
-
-	err = unisys_vmcall(VMCALL_CONTROLVM_ADDR,
-			    virt_to_phys(&dev->controlvm_params));
-	if (err)
-		return err;
-	addr = dev->controlvm_params.address;
-	chan = visorchannel_create(addr, GFP_KERNEL,
-				   &visor_controlvm_channel_guid, true);
-	if (!chan)
-		return -ENOMEM;
-	dev->controlvm_channel = chan;
-	return 0;
-}
-
-static void setup_crash_devices_work_queue(struct work_struct *work)
-{
-	struct controlvm_message local_crash_bus_msg;
-	struct controlvm_message local_crash_dev_msg;
-	struct controlvm_message msg = {
-		.hdr.id = CONTROLVM_CHIPSET_INIT,
-		.cmd.init_chipset = {
-			.bus_count = 23,
-			.switch_count = 0,
-		},
-	};
-	u32 local_crash_msg_offset;
-	u16 local_crash_msg_count;
-
-	/* send init chipset msg */
-	chipset_init(&msg);
-	/* get saved message count */
-	if (visorchannel_read(chipset_dev->controlvm_channel,
-			      offsetof(struct visor_controlvm_channel,
-				       saved_crash_message_count),
-			      &local_crash_msg_count, sizeof(u16)) < 0) {
-		dev_err(&chipset_dev->acpi_device->dev,
-			"failed to read channel\n");
-		return;
-	}
-	if (local_crash_msg_count != CONTROLVM_CRASHMSG_MAX) {
-		dev_err(&chipset_dev->acpi_device->dev, "invalid count\n");
-		return;
-	}
-	/* get saved crash message offset */
-	if (visorchannel_read(chipset_dev->controlvm_channel,
-			      offsetof(struct visor_controlvm_channel,
-				       saved_crash_message_offset),
-			      &local_crash_msg_offset, sizeof(u32)) < 0) {
-		dev_err(&chipset_dev->acpi_device->dev,
-			"failed to read channel\n");
-		return;
-	}
-	/* read create device message for storage bus offset */
-	if (visorchannel_read(chipset_dev->controlvm_channel,
-			      local_crash_msg_offset,
-			      &local_crash_bus_msg,
-			      sizeof(struct controlvm_message)) < 0) {
-		dev_err(&chipset_dev->acpi_device->dev,
-			"failed to read channel\n");
-		return;
-	}
-	/* read create device message for storage device */
-	if (visorchannel_read(chipset_dev->controlvm_channel,
-			      local_crash_msg_offset +
-			      sizeof(struct controlvm_message),
-			      &local_crash_dev_msg,
-			      sizeof(struct controlvm_message)) < 0) {
-		dev_err(&chipset_dev->acpi_device->dev,
-			"failed to read channel\n");
-		return;
-	}
-	/* reuse IOVM create bus message */
-	if (!local_crash_bus_msg.cmd.create_bus.channel_addr) {
-		dev_err(&chipset_dev->acpi_device->dev,
-			"no valid create_bus message\n");
-		return;
-	}
-	visorbus_create(&local_crash_bus_msg);
-	/* reuse create device message for storage device */
-	if (!local_crash_dev_msg.cmd.create_device.channel_addr) {
-		dev_err(&chipset_dev->acpi_device->dev,
-			"no valid create_device message\n");
-		return;
-	}
-	visorbus_device_create(&local_crash_dev_msg);
-}
-
-void visorbus_response(struct visor_device *bus_info, int response,
-		       int controlvm_id)
-{
-	if (!bus_info->pending_msg_hdr)
-		return;
-
-	controlvm_responder(controlvm_id, bus_info->pending_msg_hdr, response);
-	kfree(bus_info->pending_msg_hdr);
-	bus_info->pending_msg_hdr = NULL;
-}
-
-void visorbus_device_changestate_response(struct visor_device *dev_info,
-					  int response,
-					  struct visor_segment_state state)
-{
-	if (!dev_info->pending_msg_hdr)
-		return;
-
-	device_changestate_responder(CONTROLVM_DEVICE_CHANGESTATE, dev_info,
-				     response, state);
-	kfree(dev_info->pending_msg_hdr);
-	dev_info->pending_msg_hdr = NULL;
-}
-
-static void parser_done(struct parser_context *ctx)
-{
-	chipset_dev->controlvm_payload_bytes_buffered -= ctx->param_bytes;
-	kfree(ctx);
-}
-
-static struct parser_context *parser_init_stream(u64 addr, u32 bytes,
-						 bool *retry)
-{
-	unsigned long allocbytes;
-	struct parser_context *ctx;
-	void *mapping;
-
-	*retry = false;
-	/* alloc an extra byte to ensure payload is \0 terminated */
-	allocbytes = (unsigned long)bytes + 1 + (sizeof(struct parser_context) -
-		     sizeof(struct visor_controlvm_parameters_header));
-	if ((chipset_dev->controlvm_payload_bytes_buffered + bytes) >
-	     MAX_CONTROLVM_PAYLOAD_BYTES) {
-		*retry = true;
-		return NULL;
-	}
-	ctx = kzalloc(allocbytes, GFP_KERNEL);
-	if (!ctx) {
-		*retry = true;
-		return NULL;
-	}
-	ctx->allocbytes = allocbytes;
-	ctx->param_bytes = bytes;
-	mapping = memremap(addr, bytes, MEMREMAP_WB);
-	if (!mapping)
-		goto err_finish_ctx;
-	memcpy(&ctx->data, mapping, bytes);
-	memunmap(mapping);
-	ctx->byte_stream = true;
-	chipset_dev->controlvm_payload_bytes_buffered += ctx->param_bytes;
-	return ctx;
-
-err_finish_ctx:
-	kfree(ctx);
-	return NULL;
-}
-
-/*
- * handle_command() - process a controlvm message
- * @inmsg:        the message to process
- * @channel_addr: address of the controlvm channel
- *
- * Return:
- *	0	- Successfully processed the message
- *	-EAGAIN - ControlVM message was not processed and should be retried
- *		  reading the next controlvm message; a scenario where this can
- *		  occur is when we need to throttle the allocation of memory in
- *		  which to copy out controlvm payload data.
- *	< 0	- error: ControlVM message was processed but an error occurred.
- */
-static int handle_command(struct controlvm_message inmsg, u64 channel_addr)
-{
-	struct controlvm_message_packet *cmd = &inmsg.cmd;
-	u64 parm_addr;
-	u32 parm_bytes;
-	struct parser_context *parser_ctx = NULL;
-	struct controlvm_message ackmsg;
-	int err = 0;
-
-	/* create parsing context if necessary */
-	parm_addr = channel_addr + inmsg.hdr.payload_vm_offset;
-	parm_bytes = inmsg.hdr.payload_bytes;
-	/*
-	 * Parameter and channel addresses within test messages actually lie
-	 * within our OS-controlled memory. We need to know that, because it
-	 * makes a difference in how we compute the virtual address.
-	 */
-	if (parm_bytes) {
-		bool retry;
-
-		parser_ctx = parser_init_stream(parm_addr, parm_bytes, &retry);
-		if (!parser_ctx && retry)
-			return -EAGAIN;
-	}
-	controlvm_init_response(&ackmsg, &inmsg.hdr, CONTROLVM_RESP_SUCCESS);
-	err = visorchannel_signalinsert(chipset_dev->controlvm_channel,
-					CONTROLVM_QUEUE_ACK, &ackmsg);
-	if (err)
-		return err;
-	switch (inmsg.hdr.id) {
-	case CONTROLVM_CHIPSET_INIT:
-		err = chipset_init(&inmsg);
-		break;
-	case CONTROLVM_BUS_CREATE:
-		err = visorbus_create(&inmsg);
-		break;
-	case CONTROLVM_BUS_DESTROY:
-		err = visorbus_destroy(&inmsg);
-		break;
-	case CONTROLVM_BUS_CONFIGURE:
-		err = visorbus_configure(&inmsg, parser_ctx);
-		break;
-	case CONTROLVM_DEVICE_CREATE:
-		err = visorbus_device_create(&inmsg);
-		break;
-	case CONTROLVM_DEVICE_CHANGESTATE:
-		if (cmd->device_change_state.flags.phys_device) {
-			err = parahotplug_process_message(&inmsg);
-		} else {
-			/*
-			 * save the hdr and cmd structures for later use when
-			 * sending back the response to Command
-			 */
-			err = visorbus_device_changestate(&inmsg);
-			break;
-		}
-		break;
-	case CONTROLVM_DEVICE_DESTROY:
-		err = visorbus_device_destroy(&inmsg);
-		break;
-	case CONTROLVM_DEVICE_CONFIGURE:
-		/* no op just send a respond that we passed */
-		if (inmsg.hdr.flags.response_expected)
-			controlvm_respond(&inmsg.hdr, CONTROLVM_RESP_SUCCESS,
-					  NULL);
-		break;
-	case CONTROLVM_CHIPSET_READY:
-		err = chipset_ready_uevent(&inmsg.hdr);
-		break;
-	case CONTROLVM_CHIPSET_SELFTEST:
-		err = chipset_selftest_uevent(&inmsg.hdr);
-		break;
-	case CONTROLVM_CHIPSET_STOP:
-		err = chipset_notready_uevent(&inmsg.hdr);
-		break;
-	default:
-		err = -ENOMSG;
-		if (inmsg.hdr.flags.response_expected)
-			controlvm_respond(&inmsg.hdr,
-					  -CONTROLVM_RESP_ID_UNKNOWN, NULL);
-		break;
-	}
-	if (parser_ctx) {
-		parser_done(parser_ctx);
-		parser_ctx = NULL;
-	}
-	return err;
-}
-
-/*
- * read_controlvm_event() - retreives the next message from the
- *                          CONTROLVM_QUEUE_EVENT queue in the controlvm
- *                          channel
- * @msg: pointer to the retrieved message
- *
- * Return: 0 if valid message was retrieved or -error
- */
-static int read_controlvm_event(struct controlvm_message *msg)
-{
-	int err = visorchannel_signalremove(chipset_dev->controlvm_channel,
-					    CONTROLVM_QUEUE_EVENT, msg);
-
-	if (err)
-		return err;
-	/* got a message */
-	if (msg->hdr.flags.test_message == 1)
-		return -EINVAL;
-	return 0;
-}
-
-/*
- * parahotplug_process_list() - remove any request from the list that's been on
- *                              there too long and respond with an error
- */
-static void parahotplug_process_list(void)
-{
-	struct list_head *pos;
-	struct list_head *tmp;
-
-	spin_lock(&parahotplug_request_list_lock);
-	list_for_each_safe(pos, tmp, &parahotplug_request_list) {
-		struct parahotplug_request *req =
-		    list_entry(pos, struct parahotplug_request, list);
-
-		if (!time_after_eq(jiffies, req->expiration))
-			continue;
-		list_del(pos);
-		if (req->msg.hdr.flags.response_expected)
-			controlvm_respond(
-				&req->msg.hdr,
-				CONTROLVM_RESP_DEVICE_UDEV_TIMEOUT,
-				&req->msg.cmd.device_change_state.state);
-		parahotplug_request_destroy(req);
-	}
-	spin_unlock(&parahotplug_request_list_lock);
-}
-
-static void controlvm_periodic_work(struct work_struct *work)
-{
-	struct controlvm_message inmsg;
-	int count = 0;
-	int err;
-
-	/* Drain the RESPONSE queue make it empty */
-	do {
-		err = visorchannel_signalremove(chipset_dev->controlvm_channel,
-						CONTROLVM_QUEUE_RESPONSE,
-						&inmsg);
-	} while ((!err) && (++count < CONTROLVM_MESSAGE_MAX));
-	if (err != -EAGAIN)
-		goto schedule_out;
-	if (chipset_dev->controlvm_pending_msg_valid) {
-		/*
-		 * we throttled processing of a prior msg, so try to process
-		 * it again rather than reading a new one
-		 */
-		inmsg = chipset_dev->controlvm_pending_msg;
-		chipset_dev->controlvm_pending_msg_valid = false;
-		err = 0;
-	} else {
-		err = read_controlvm_event(&inmsg);
-	}
-	while (!err) {
-		chipset_dev->most_recent_message_jiffies = jiffies;
-		err = handle_command(inmsg,
-				     visorchannel_get_physaddr
-				     (chipset_dev->controlvm_channel));
-		if (err == -EAGAIN) {
-			chipset_dev->controlvm_pending_msg = inmsg;
-			chipset_dev->controlvm_pending_msg_valid = true;
-			break;
-		}
-
-		err = read_controlvm_event(&inmsg);
-	}
-	/* parahotplug_worker */
-	parahotplug_process_list();
-
-/*
- * The controlvm messages are sent in a bulk. If we start receiving messages, we
- * want the polling to be fast. If we do not receive any message for
- * MIN_IDLE_SECONDS, we can slow down the polling.
- */
-schedule_out:
-	if (time_after(jiffies, chipset_dev->most_recent_message_jiffies +
-				(HZ * MIN_IDLE_SECONDS))) {
-		/*
-		 * it's been longer than MIN_IDLE_SECONDS since we processed
-		 * our last controlvm message; slow down the polling
-		 */
-		if (chipset_dev->poll_jiffies != POLLJIFFIES_CONTROLVM_SLOW)
-			chipset_dev->poll_jiffies = POLLJIFFIES_CONTROLVM_SLOW;
-	} else {
-		if (chipset_dev->poll_jiffies != POLLJIFFIES_CONTROLVM_FAST)
-			chipset_dev->poll_jiffies = POLLJIFFIES_CONTROLVM_FAST;
-	}
-	schedule_delayed_work(&chipset_dev->periodic_controlvm_work,
-			      chipset_dev->poll_jiffies);
-}
-
-static int visorchipset_init(struct acpi_device *acpi_device)
-{
-	int err = -ENOMEM;
-	struct visorchannel *controlvm_channel;
-
-	chipset_dev = kzalloc(sizeof(*chipset_dev), GFP_KERNEL);
-	if (!chipset_dev)
-		goto error;
-	err = controlvm_channel_create(chipset_dev);
-	if (err)
-		goto error_free_chipset_dev;
-	acpi_device->driver_data = chipset_dev;
-	chipset_dev->acpi_device = acpi_device;
-	chipset_dev->poll_jiffies = POLLJIFFIES_CONTROLVM_FAST;
-	err = sysfs_create_groups(&chipset_dev->acpi_device->dev.kobj,
-				  visorchipset_dev_groups);
-	if (err < 0)
-		goto error_destroy_channel;
-	controlvm_channel = chipset_dev->controlvm_channel;
-	if (!visor_check_channel(visorchannel_get_header(controlvm_channel),
-				 &chipset_dev->acpi_device->dev,
-				 &visor_controlvm_channel_guid,
-				 "controlvm",
-				 sizeof(struct visor_controlvm_channel),
-				 VISOR_CONTROLVM_CHANNEL_VERSIONID,
-				 VISOR_CHANNEL_SIGNATURE)) {
-		err = -ENODEV;
-		goto error_delete_groups;
-	}
-	/* if booting in a crash kernel */
-	if (is_kdump_kernel())
-		INIT_DELAYED_WORK(&chipset_dev->periodic_controlvm_work,
-				  setup_crash_devices_work_queue);
-	else
-		INIT_DELAYED_WORK(&chipset_dev->periodic_controlvm_work,
-				  controlvm_periodic_work);
-	chipset_dev->most_recent_message_jiffies = jiffies;
-	chipset_dev->poll_jiffies = POLLJIFFIES_CONTROLVM_FAST;
-	schedule_delayed_work(&chipset_dev->periodic_controlvm_work,
-			      chipset_dev->poll_jiffies);
-	err = visorbus_init();
-	if (err < 0)
-		goto error_cancel_work;
-	return 0;
-
-error_cancel_work:
-	cancel_delayed_work_sync(&chipset_dev->periodic_controlvm_work);
-
-error_delete_groups:
-	sysfs_remove_groups(&chipset_dev->acpi_device->dev.kobj,
-			    visorchipset_dev_groups);
-
-error_destroy_channel:
-	visorchannel_destroy(chipset_dev->controlvm_channel);
-
-error_free_chipset_dev:
-	kfree(chipset_dev);
-
-error:
-	dev_err(&acpi_device->dev, "failed with error %d\n", err);
-	return err;
-}
-
-static int visorchipset_exit(struct acpi_device *acpi_device)
-{
-	visorbus_exit();
-	cancel_delayed_work_sync(&chipset_dev->periodic_controlvm_work);
-	sysfs_remove_groups(&chipset_dev->acpi_device->dev.kobj,
-			    visorchipset_dev_groups);
-	visorchannel_destroy(chipset_dev->controlvm_channel);
-	kfree(chipset_dev);
-	return 0;
-}
-
-static const struct acpi_device_id unisys_device_ids[] = {
-	{"PNP0A07", 0},
-	{"", 0},
-};
-
-static struct acpi_driver unisys_acpi_driver = {
-	.name = "unisys_acpi",
-	.class = "unisys_acpi_class",
-	.owner = THIS_MODULE,
-	.ids = unisys_device_ids,
-	.ops = {
-		.add = visorchipset_init,
-		.remove = visorchipset_exit,
-	},
-};
-
-MODULE_DEVICE_TABLE(acpi, unisys_device_ids);
-
-static __init int visorutil_spar_detect(void)
-{
-	unsigned int eax, ebx, ecx, edx;
-
-	if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) {
-		/* check the ID */
-		cpuid(UNISYS_VISOR_LEAF_ID, &eax, &ebx, &ecx, &edx);
-		return  (ebx == UNISYS_VISOR_ID_EBX) &&
-			(ecx == UNISYS_VISOR_ID_ECX) &&
-			(edx == UNISYS_VISOR_ID_EDX);
-	}
-	return 0;
-}
-
-static int __init init_unisys(void)
-{
-	int result;
-
-	if (!visorutil_spar_detect())
-		return -ENODEV;
-	result = acpi_bus_register_driver(&unisys_acpi_driver);
-	if (result)
-		return -ENODEV;
-	pr_info("Unisys Visorchipset Driver Loaded.\n");
-	return 0;
-};
-
-static void __exit exit_unisys(void)
-{
-	acpi_bus_unregister_driver(&unisys_acpi_driver);
-}
-
-module_init(init_unisys);
-module_exit(exit_unisys);
-
-MODULE_AUTHOR("Unisys");
-MODULE_LICENSE("GPL");
-MODULE_DESCRIPTION("s-Par visorbus driver for virtual device buses");