1 files changed, 250 insertions, 357 deletions

diff --git a/drivers/staging/unisys/visorbus/visorchipset.c b/drivers/staging/unisys/visorbus/visorchipset.c
index 22150564b4fb..74cce4f1a7bd 100644
--- a/drivers/staging/unisys/visorbus/visorchipset.c
+++ b/drivers/staging/unisys/visorbus/visorchipset.c
@@ -1,5 +1,4 @@
-/* visorchipset_main.c
- *
+/*
  * Copyright (C) 2010 - 2015 UNISYS CORPORATION
  * All rights reserved.
  *
@@ -15,19 +14,18 @@
  */
 
 #include <linux/acpi.h>
-#include <linux/ctype.h>
-#include <linux/fs.h>
-#include <linux/mm.h>
-#include <linux/nls.h>
-#include <linux/netdevice.h>
-#include <linux/uuid.h>
 #include <linux/crash_dump.h>
 
 #include "visorbus.h"
 #include "visorbus_private.h"
-#include "vmcallinterface.h"
 
-#define CURRENT_FILE_PC VISOR_BUS_PC_visorchipset_c
+/* {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_CONTROLVMCHANNEL_FAST 1
 #define POLLJIFFIES_CONTROLVMCHANNEL_SLOW 100
@@ -42,9 +40,9 @@
 #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.
+ * 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
 
@@ -54,15 +52,39 @@ struct parser_context {
 	u8 *curr;
 	unsigned long bytes_remaining;
 	bool byte_stream;
-	char data[0];
+	struct visor_controlvm_parameters_header data;
 };
 
-struct vmcall_controlvm_addr {
-	struct vmcall_io_controlvm_addr_params params;
-	int err;
-	u64 physaddr;
+/* 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;
@@ -80,7 +102,7 @@ struct visorchipset_device {
 	 */
 	struct controlvm_message controlvm_pending_msg;
 	bool controlvm_pending_msg_valid;
-	struct vmcall_controlvm_addr controlvm_addr;
+	struct vmcall_io_controlvm_addr_params controlvm_params;
 };
 
 static struct visorchipset_device *chipset_dev;
@@ -124,7 +146,6 @@ static ssize_t toolaction_store(struct device *dev,
 				 offsetof(struct visor_controlvm_channel,
 					  tool_action),
 				 &tool_action, sizeof(u8));
-
 	if (err)
 		return err;
 	return count;
@@ -143,7 +164,6 @@ static ssize_t boottotool_show(struct device *dev,
 					 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);
@@ -165,7 +185,6 @@ static ssize_t boottotool_store(struct device *dev,
 					  efi_visor_ind),
 				 &(efi_visor_indication),
 				 sizeof(struct efi_visor_indication));
-
 	if (err)
 		return err;
 	return count;
@@ -184,7 +203,7 @@ static ssize_t error_show(struct device *dev, struct device_attribute *attr,
 				&error, sizeof(u32));
 	if (err)
 		return err;
-	return sprintf(buf, "%i\n", error);
+	return sprintf(buf, "%u\n", error);
 }
 
 static ssize_t error_store(struct device *dev, struct device_attribute *attr,
@@ -219,7 +238,7 @@ static ssize_t textid_show(struct device *dev, struct device_attribute *attr,
 	if (err)
 		return err;
 
-	return sprintf(buf, "%i\n", text_id);
+	return sprintf(buf, "%u\n", text_id);
 }
 
 static ssize_t textid_store(struct device *dev, struct device_attribute *attr,
@@ -277,67 +296,6 @@ static ssize_t remaining_steps_store(struct device *dev,
 }
 static DEVICE_ATTR_RW(remaining_steps);
 
-static uuid_le
-parser_id_get(struct parser_context *ctx)
-{
-	struct visor_controlvm_parameters_header *phdr = NULL;
-
-	phdr = (struct visor_controlvm_parameters_header *)(ctx->data);
-	return phdr->id;
-}
-
-static void parser_done(struct parser_context *ctx)
-{
-	chipset_dev->controlvm_payload_bytes_buffered -= ctx->param_bytes;
-	kfree(ctx);
-}
-
-static void *
-parser_string_get(struct parser_context *ctx)
-{
-	u8 *pscan;
-	unsigned long nscan;
-	int value_length = -1;
-	void *value = NULL;
-	int i;
-
-	pscan = ctx->curr;
-	nscan = ctx->bytes_remaining;
-	if (nscan == 0)
-		return NULL;
-	if (!pscan)
-		return NULL;
-	for (i = 0, value_length = -1; i < nscan; i++)
-		if (pscan[i] == '\0') {
-			value_length = i;
-			break;
-		}
-	if (value_length < 0)	/* '\0' was not included in the length */
-		value_length = nscan;
-	value = kmalloc(value_length + 1, GFP_KERNEL);
-	if (!value)
-		return NULL;
-	if (value_length > 0)
-		memcpy(value, pscan, value_length);
-	((u8 *)(value))[value_length] = '\0';
-	return value;
-}
-
-static void *
-parser_name_get(struct parser_context *ctx)
-{
-	struct visor_controlvm_parameters_header *phdr = NULL;
-
-	phdr = (struct visor_controlvm_parameters_header *)(ctx->data);
-
-	if (phdr->name_offset + phdr->name_length > ctx->param_bytes)
-		return NULL;
-
-	ctx->curr = ctx->data + phdr->name_offset;
-	ctx->bytes_remaining = phdr->name_length;
-	return parser_string_get(ctx);
-}
-
 struct visor_busdev {
 	u32 bus_no;
 	u32 dev_no;
@@ -347,11 +305,9 @@ static int match_visorbus_dev_by_id(struct device *dev, void *data)
 {
 	struct visor_device *vdev = to_visor_device(dev);
 	struct visor_busdev *id = data;
-	u32 bus_no = id->bus_no;
-	u32 dev_no = id->dev_no;
 
-	if ((vdev->chipset_bus_no == bus_no) &&
-	    (vdev->chipset_dev_no == dev_no))
+	if ((vdev->chipset_bus_no == id->bus_no) &&
+	    (vdev->chipset_dev_no == id->dev_no))
 		return 1;
 
 	return 0;
@@ -364,9 +320,9 @@ struct visor_device *visorbus_get_device_by_id(u32 bus_no, u32 dev_no,
 	struct device *dev_start = NULL;
 	struct visor_device *vdev = NULL;
 	struct visor_busdev id = {
-			.bus_no = bus_no,
-			.dev_no = dev_no
-		};
+		.bus_no = bus_no,
+		.dev_no = dev_no
+	};
 
 	if (from)
 		dev_start = &from->device;
@@ -377,9 +333,9 @@ struct visor_device *visorbus_get_device_by_id(u32 bus_no, u32 dev_no,
 	return vdev;
 }
 
-static void
-controlvm_init_response(struct controlvm_message *msg,
-			struct controlvm_message_header *msg_hdr, int response)
+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));
@@ -392,10 +348,10 @@ controlvm_init_response(struct controlvm_message *msg,
 	}
 }
 
-static int
-controlvm_respond_chipset_init(struct controlvm_message_header *msg_hdr,
-			       int response,
-			       enum visor_chipset_feature features)
+static int controlvm_respond_chipset_init(
+				struct controlvm_message_header *msg_hdr,
+				int response,
+				enum visor_chipset_feature features)
 {
 	struct controlvm_message outmsg;
 
@@ -405,8 +361,7 @@ controlvm_respond_chipset_init(struct controlvm_message_header *msg_hdr,
 					 CONTROLVM_QUEUE_REQUEST, &outmsg);
 }
 
-static int
-chipset_init(struct controlvm_message *inmsg)
+static int chipset_init(struct controlvm_message *inmsg)
 {
 	static int chipset_inited;
 	enum visor_chipset_feature features = 0;
@@ -421,15 +376,15 @@ chipset_init(struct controlvm_message *inmsg)
 	chipset_inited = 1;
 
 	/*
-	 * Set features to indicate we support parahotplug (if Command
-	 * also supports it).
+	 * Set features to indicate we support parahotplug (if Command also
+	 * supports it).
 	 */
 	features = inmsg->cmd.init_chipset.features &
 		   VISOR_CHIPSET_FEATURE_PARA_HOTPLUG;
 
 	/*
-	 * Set the "reply" bit so Command knows this is a
-	 * features-aware driver.
+	 * Set the "reply" bit so Command knows this is a features-aware
+	 * driver.
 	 */
 	features |= VISOR_CHIPSET_FEATURE_REPLY;
 
@@ -440,9 +395,9 @@ out_respond:
 	return res;
 }
 
-static int
-controlvm_respond(struct controlvm_message_header *msg_hdr, int response,
-		  struct visor_segment_state *state)
+static int controlvm_respond(struct controlvm_message_header *msg_hdr,
+			     int response,
+			     struct visor_segment_state *state)
 {
 	struct controlvm_message outmsg;
 
@@ -464,8 +419,8 @@ enum crash_obj_type {
 	CRASH_BUS,
 };
 
-static int
-save_crash_message(struct controlvm_message *msg, enum crash_obj_type cr_type)
+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;
@@ -529,10 +484,9 @@ save_crash_message(struct controlvm_message *msg, enum crash_obj_type cr_type)
 	return 0;
 }
 
-static int
-controlvm_responder(enum controlvm_id cmd_id,
-		    struct controlvm_message_header *pending_msg_hdr,
-		    int response)
+static int controlvm_responder(enum controlvm_id cmd_id,
+			       struct controlvm_message_header *pending_msg_hdr,
+			       int response)
 {
 	if (!pending_msg_hdr)
 		return -EIO;
@@ -543,14 +497,12 @@ controlvm_responder(enum controlvm_id cmd_id,
 	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 response_state)
+static int device_changestate_responder(
+				enum controlvm_id cmd_id,
+				struct visor_device *p, int response,
+				struct visor_segment_state response_state)
 {
 	struct controlvm_message outmsg;
-	u32 bus_no = p->chipset_bus_no;
-	u32 dev_no = p->chipset_dev_no;
 
 	if (!p->pending_msg_hdr)
 		return -EIO;
@@ -559,16 +511,15 @@ device_changestate_responder(enum controlvm_id cmd_id,
 
 	controlvm_init_response(&outmsg, p->pending_msg_hdr, response);
 
-	outmsg.cmd.device_change_state.bus_no = bus_no;
-	outmsg.cmd.device_change_state.dev_no = dev_no;
+	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 = response_state;
 
 	return visorchannel_signalinsert(chipset_dev->controlvm_channel,
 					 CONTROLVM_QUEUE_REQUEST, &outmsg);
 }
 
-static int
-visorbus_create(struct controlvm_message *inmsg)
+static int visorbus_create(struct controlvm_message *inmsg)
 {
 	struct controlvm_message_packet *cmd = &inmsg->cmd;
 	struct controlvm_message_header *pmsg_hdr = NULL;
@@ -580,7 +531,7 @@ visorbus_create(struct controlvm_message *inmsg)
 	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 visorbus_create: already exists\n");
+			"failed %s: already exists\n", __func__);
 		err = -EEXIST;
 		goto err_respond;
 	}
@@ -595,7 +546,7 @@ visorbus_create(struct controlvm_message *inmsg)
 	bus_info->chipset_bus_no = bus_no;
 	bus_info->chipset_dev_no = BUS_ROOT_DEVICE;
 
-	if (uuid_le_cmp(cmd->create_bus.bus_inst_uuid, visor_siovm_uuid) == 0) {
+	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;
@@ -615,19 +566,17 @@ visorbus_create(struct controlvm_message *inmsg)
 	}
 
 	visorchannel = visorchannel_create(cmd->create_bus.channel_addr,
-					   cmd->create_bus.channel_bytes,
 					   GFP_KERNEL,
-					   cmd->create_bus.bus_data_type_uuid);
-
+					   &cmd->create_bus.bus_data_type_guid);
 	if (!visorchannel) {
 		err = -ENOMEM;
 		goto err_free_pending_msg;
 	}
+
 	bus_info->visorchannel = visorchannel;
 
-	/* Response will be handled by visorchipset_bus_create */
-	err = visorchipset_bus_create(bus_info);
-	/* If visorchipset_bus_create didn't respond, need to respond here */
+	/* Response will be handled by visorbus_create_instance on success */
+	err = visorbus_create_instance(bus_info);
 	if (err)
 		goto err_destroy_channel;
 
@@ -648,8 +597,7 @@ err_respond:
 	return err;
 }
 
-static int
-visorbus_destroy(struct controlvm_message *inmsg)
+static int visorbus_destroy(struct controlvm_message *inmsg)
 {
 	struct controlvm_message_packet *cmd = &inmsg->cmd;
 	struct controlvm_message_header *pmsg_hdr = NULL;
@@ -683,8 +631,8 @@ visorbus_destroy(struct controlvm_message *inmsg)
 		bus_info->pending_msg_hdr = pmsg_hdr;
 	}
 
-	/* Response will be handled by visorchipset_bus_destroy */
-	visorchipset_bus_destroy(bus_info);
+	/* Response will be handled by visorbus_remove_instance */
+	visorbus_remove_instance(bus_info);
 	return 0;
 
 err_respond:
@@ -693,9 +641,60 @@ err_respond:
 	return err;
 }
 
-static int
-visorbus_configure(struct controlvm_message *inmsg,
-		   struct parser_context *parser_ctx)
+static const guid_t *parser_id_get(struct parser_context *ctx)
+{
+	return &ctx->data.id;
+}
+
+static void *parser_string_get(struct parser_context *ctx)
+{
+	u8 *pscan;
+	unsigned long nscan;
+	int value_length;
+	void *value;
+	int i;
+
+	pscan = ctx->curr;
+	if (!pscan)
+		return NULL;
+	nscan = ctx->bytes_remaining;
+	if (nscan == 0)
+		return NULL;
+
+	for (i = 0, value_length = -1; i < nscan; i++)
+		if (pscan[i] == '\0') {
+			value_length = i;
+			break;
+		}
+	/* '\0' was not included in the length */
+	if (value_length < 0)
+		value_length = nscan;
+
+	value = kmalloc(value_length + 1, GFP_KERNEL);
+	if (!value)
+		return NULL;
+	if (value_length > 0)
+		memcpy(value, pscan, value_length);
+	((u8 *)(value))[value_length] = '\0';
+	return value;
+}
+
+static void *parser_name_get(struct parser_context *ctx)
+{
+	struct visor_controlvm_parameters_header *phdr = NULL;
+
+	phdr = &ctx->data;
+
+	if (phdr->name_offset + 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);
+}
+
+static int visorbus_configure(struct controlvm_message *inmsg,
+			      struct parser_context *parser_ctx)
 {
 	struct controlvm_message_packet *cmd = &inmsg->cmd;
 	u32 bus_no;
@@ -707,10 +706,12 @@ visorbus_configure(struct controlvm_message *inmsg,
 	if (!bus_info) {
 		err = -EINVAL;
 		goto err_respond;
-	} else if (bus_info->state.created == 0) {
+	}
+	if (bus_info->state.created == 0) {
 		err = -EINVAL;
 		goto err_respond;
-	} else if (bus_info->pending_msg_hdr) {
+	}
+	if (bus_info->pending_msg_hdr) {
 		err = -EIO;
 		goto err_respond;
 	}
@@ -722,7 +723,9 @@ visorbus_configure(struct controlvm_message *inmsg,
 		goto err_respond;
 
 	if (parser_ctx) {
-		bus_info->partition_uuid = parser_id_get(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);
 	}
 
@@ -732,14 +735,13 @@ visorbus_configure(struct controlvm_message *inmsg,
 
 err_respond:
 	dev_err(&chipset_dev->acpi_device->dev,
-		"visorbus_configure exited with err: %d\n", err);
+		"%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)
+static int visorbus_device_create(struct controlvm_message *inmsg)
 {
 	struct controlvm_message_packet *cmd = &inmsg->cmd;
 	struct controlvm_message_header *pmsg_hdr = NULL;
@@ -757,7 +759,6 @@ visorbus_device_create(struct controlvm_message *inmsg)
 		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);
@@ -781,17 +782,13 @@ visorbus_device_create(struct controlvm_message *inmsg)
 
 	dev_info->chipset_bus_no = bus_no;
 	dev_info->chipset_dev_no = dev_no;
-	dev_info->inst = cmd->create_device.dev_inst_uuid;
-
-	/* not sure where the best place to set the 'parent' */
+	guid_copy(&dev_info->inst, &cmd->create_device.dev_inst_guid);
 	dev_info->device.parent = &bus_info->device;
 
 	visorchannel =
 	       visorchannel_create_with_lock(cmd->create_device.channel_addr,
-					     cmd->create_device.channel_bytes,
 					     GFP_KERNEL,
-					     cmd->create_device.data_type_uuid);
-
+					     &cmd->create_device.data_type_guid);
 	if (!visorchannel) {
 		dev_err(&chipset_dev->acpi_device->dev,
 			"failed to create visorchannel: %d/%d\n",
@@ -800,9 +797,8 @@ visorbus_device_create(struct controlvm_message *inmsg)
 		goto err_free_dev_info;
 	}
 	dev_info->visorchannel = visorchannel;
-	dev_info->channel_type_guid = cmd->create_device.data_type_uuid;
-	if (uuid_le_cmp(cmd->create_device.data_type_uuid,
-			visor_vhba_channel_uuid) == 0) {
+	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;
@@ -819,8 +815,8 @@ visorbus_device_create(struct controlvm_message *inmsg)
 		       sizeof(struct controlvm_message_header));
 		dev_info->pending_msg_hdr = pmsg_hdr;
 	}
-	/* visorchipset_device_create will send response */
-	err = visorchipset_device_create(dev_info);
+	/* create_visor_device will send response */
+	err = create_visor_device(dev_info);
 	if (err)
 		goto err_destroy_visorchannel;
 
@@ -838,8 +834,7 @@ err_respond:
 	return err;
 }
 
-static int
-visorbus_device_changestate(struct controlvm_message *inmsg)
+static int visorbus_device_changestate(struct controlvm_message *inmsg)
 {
 	struct controlvm_message_packet *cmd = &inmsg->cmd;
 	struct controlvm_message_header *pmsg_hdr = NULL;
@@ -899,8 +894,7 @@ err_respond:
 	return err;
 }
 
-static int
-visorbus_device_destroy(struct controlvm_message *inmsg)
+static int visorbus_device_destroy(struct controlvm_message *inmsg)
 {
 	struct controlvm_message_packet *cmd = &inmsg->cmd;
 	struct controlvm_message_header *pmsg_hdr = NULL;
@@ -918,7 +912,6 @@ visorbus_device_destroy(struct controlvm_message *inmsg)
 		err = -EINVAL;
 		goto err_respond;
 	}
-
 	if (dev_info->pending_msg_hdr) {
 		/* only non-NULL if dev is still waiting on a response */
 		err = -EIO;
@@ -936,7 +929,8 @@ visorbus_device_destroy(struct controlvm_message *inmsg)
 		dev_info->pending_msg_hdr = pmsg_hdr;
 	}
 
-	visorchipset_device_destroy(dev_info);
+	kfree(dev_info->name);
+	remove_visor_device(dev_info);
 	return 0;
 
 err_respond:
@@ -954,8 +948,7 @@ err_respond:
  * 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.
+ * appropriate CONTROLVM message is retrieved from the list and responded to.
  */
 
 #define PARAHOTPLUG_TIMEOUT_MS 2000
@@ -967,8 +960,7 @@ err_respond:
  *
  * Return: a unique integer value
  */
-static int
-parahotplug_next_id(void)
+static int parahotplug_next_id(void)
 {
 	static atomic_t id = ATOMIC_INIT(0);
 
@@ -982,8 +974,7 @@ parahotplug_next_id(void)
  *
  * Return: expected expiration time (in jiffies)
  */
-static unsigned long
-parahotplug_next_expiration(void)
+static unsigned long parahotplug_next_expiration(void)
 {
 	return jiffies + msecs_to_jiffies(PARAHOTPLUG_TIMEOUT_MS);
 }
@@ -996,8 +987,8 @@ parahotplug_next_expiration(void)
  *
  * Return: the request containing the provided message
  */
-static struct parahotplug_request *
-parahotplug_request_create(struct controlvm_message *msg)
+static struct parahotplug_request *parahotplug_request_create(
+						struct controlvm_message *msg)
 {
 	struct parahotplug_request *req;
 
@@ -1016,14 +1007,14 @@ parahotplug_request_create(struct controlvm_message *msg)
  * parahotplug_request_destroy() - free a parahotplug_request
  * @req: the request to deallocate
  */
-static void
-parahotplug_request_destroy(struct parahotplug_request *req)
+static void parahotplug_request_destroy(struct parahotplug_request *req)
 {
 	kfree(req);
 }
 
 static LIST_HEAD(parahotplug_request_list);
-static DEFINE_SPINLOCK(parahotplug_request_list_lock);	/* lock for above */
+/* lock for above */
+static DEFINE_SPINLOCK(parahotplug_request_list_lock);
 
 /*
  * parahotplug_request_complete() - mark request as complete
@@ -1036,8 +1027,7 @@ static DEFINE_SPINLOCK(parahotplug_request_list_lock);	/* lock for above */
  *
  * Return: 0 on success or -EINVAL on failure
  */
-static int
-parahotplug_request_complete(int id, u16 active)
+static int parahotplug_request_complete(int id, u16 active)
 {
 	struct list_head *pos;
 	struct list_head *tmp;
@@ -1146,7 +1136,7 @@ static struct attribute *visorchipset_parahotplug_attrs[] = {
 	NULL
 };
 
-static struct attribute_group visorchipset_parahotplug_group = {
+static const struct attribute_group visorchipset_parahotplug_group = {
 	.name = "parahotplug",
 	.attrs = visorchipset_parahotplug_attrs
 };
@@ -1164,8 +1154,7 @@ static const struct attribute_group *visorchipset_dev_groups[] = {
  * 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)
+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],
@@ -1194,14 +1183,12 @@ parahotplug_request_kickoff(struct parahotplug_request *req)
  *                                 off a udev script
  * @inmsg: the message indicating whether to enable or disable
  */
-static int
-parahotplug_process_message(struct controlvm_message *inmsg)
+static int parahotplug_process_message(struct controlvm_message *inmsg)
 {
 	struct parahotplug_request *req;
 	int err;
 
 	req = parahotplug_request_create(inmsg);
-
 	if (!req)
 		return -ENOMEM;
 
@@ -1220,10 +1207,9 @@ parahotplug_process_message(struct controlvm_message *inmsg)
 	}
 
 	/*
-	 * 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.
+	 * 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);
@@ -1247,8 +1233,7 @@ err_respond:
  *
  * Return: 0 on success, negative on failure
  */
-static int
-chipset_ready_uevent(struct controlvm_message_header *msg_hdr)
+static int chipset_ready_uevent(struct controlvm_message_header *msg_hdr)
 {
 	int res;
 
@@ -1268,8 +1253,7 @@ chipset_ready_uevent(struct controlvm_message_header *msg_hdr)
  *
  * Return: 0 on success, negative on failure
  */
-static int
-chipset_selftest_uevent(struct controlvm_message_header *msg_hdr)
+static int chipset_selftest_uevent(struct controlvm_message_header *msg_hdr)
 {
 	char env_selftest[20];
 	char *envp[] = { env_selftest, NULL };
@@ -1292,13 +1276,11 @@ chipset_selftest_uevent(struct controlvm_message_header *msg_hdr)
  *
  * Return: 0 on success, negative on failure
  */
-static int
-chipset_notready_uevent(struct controlvm_message_header *msg_hdr)
+static int chipset_notready_uevent(struct controlvm_message_header *msg_hdr)
 {
-	int res;
-
-	res = kobject_uevent(&chipset_dev->acpi_device->dev.kobj,
+	int res = kobject_uevent(&chipset_dev->acpi_device->dev.kobj,
 			     KOBJ_OFFLINE);
+
 	if (msg_hdr->flags.response_expected)
 		controlvm_respond(msg_hdr, res, NULL);
 
@@ -1321,13 +1303,12 @@ static int unisys_vmcall(unsigned long tuple, unsigned long param)
 
 	__asm__ __volatile__(".byte 0x00f, 0x001, 0x0c1" : "=a"(result) :
 		"a"(tuple), "b"(reg_ebx), "c"(reg_ecx));
-
 	if (result)
 		goto error;
 
 	return 0;
-
-error: /* Need to convert from VMCALL error codes to Linux */
+/* Need to convert from VMCALL error codes to Linux */
+error:
 	switch (result) {
 	case VMCALL_RESULT_INVALID_PARAM:
 		return -EINVAL;
@@ -1337,35 +1318,27 @@ error: /* Need to convert from VMCALL error codes to Linux */
 		return -EFAULT;
 	}
 }
-static unsigned int
-issue_vmcall_io_controlvm_addr(u64 *control_addr, u32 *control_bytes)
-{
-	chipset_dev->controlvm_addr.physaddr = virt_to_phys(
-					   &chipset_dev->controlvm_addr.params);
-	chipset_dev->controlvm_addr.err = unisys_vmcall(VMCALL_CONTROLVM_ADDR,
-					  chipset_dev->controlvm_addr.physaddr);
-	if (chipset_dev->controlvm_addr.err)
-		return chipset_dev->controlvm_addr.err;
-
-	*control_addr = chipset_dev->controlvm_addr.params.address;
-	*control_bytes = chipset_dev->controlvm_addr.params.channel_bytes;
-
-	return 0;
-}
 
-static u64 controlvm_get_channel_address(void)
+static int controlvm_channel_create(struct visorchipset_device *dev)
 {
-	u64 addr = 0;
-	u32 size = 0;
-
-	if (issue_vmcall_io_controlvm_addr(&addr, &size))
-		return 0;
+	struct visorchannel *chan;
+	u64 addr;
+	int err;
 
-	return addr;
+	err = unisys_vmcall(VMCALL_CONTROLVM_ADDR,
+			    virt_to_phys(&dev->controlvm_params));
+	if (err)
+		return err;
+	addr = dev->controlvm_params.address;
+	chan = visorchannel_create_with_lock(addr, GFP_KERNEL,
+					     &visor_controlvm_channel_guid);
+	if (!chan)
+		return -ENOMEM;
+	dev->controlvm_channel = chan;
+	return 0;
 }
 
-static void
-setup_crash_devices_work_queue(struct work_struct *work)
+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;
@@ -1444,87 +1417,44 @@ setup_crash_devices_work_queue(struct work_struct *work)
 	visorbus_device_create(&local_crash_dev_msg);
 }
 
-void
-visorbus_create_response(struct visor_device *bus_info, int response)
+void visorbus_response(struct visor_device *bus_info, int response,
+		       int controlvm_id)
 {
-	if (response >= 0)
-		bus_info->state.created = 1;
-
-	controlvm_responder(CONTROLVM_BUS_CREATE, bus_info->pending_msg_hdr,
-			    response);
+	controlvm_responder(controlvm_id, bus_info->pending_msg_hdr, response);
 
 	kfree(bus_info->pending_msg_hdr);
 	bus_info->pending_msg_hdr = NULL;
 }
 
-void
-visorbus_destroy_response(struct visor_device *bus_info, int response)
-{
-	controlvm_responder(CONTROLVM_BUS_DESTROY, bus_info->pending_msg_hdr,
-			    response);
-
-	kfree(bus_info->pending_msg_hdr);
-	bus_info->pending_msg_hdr = NULL;
-}
-
-void
-visorbus_device_create_response(struct visor_device *dev_info, int response)
-{
-	if (response >= 0)
-		dev_info->state.created = 1;
-
-	controlvm_responder(CONTROLVM_DEVICE_CREATE, dev_info->pending_msg_hdr,
-			    response);
-
-	kfree(dev_info->pending_msg_hdr);
-	dev_info->pending_msg_hdr = NULL;
-}
-
-void
-visorbus_device_destroy_response(struct visor_device *dev_info, int response)
-{
-	controlvm_responder(CONTROLVM_DEVICE_DESTROY, dev_info->pending_msg_hdr,
-			    response);
-
-	kfree(dev_info->pending_msg_hdr);
-	dev_info->pending_msg_hdr = NULL;
-}
-
-void
-visorbus_device_pause_response(struct visor_device *dev_info, int response)
+void visorbus_device_changestate_response(struct visor_device *dev_info,
+					  int response,
+					  struct visor_segment_state state)
 {
 	device_changestate_responder(CONTROLVM_DEVICE_CHANGESTATE,
-				     dev_info, response,
-				     segment_state_standby);
+				     dev_info, response, state);
 
 	kfree(dev_info->pending_msg_hdr);
 	dev_info->pending_msg_hdr = NULL;
 }
 
-void
-visorbus_device_resume_response(struct visor_device *dev_info, int response)
+static void parser_done(struct parser_context *ctx)
 {
-	device_changestate_responder(CONTROLVM_DEVICE_CHANGESTATE,
-				     dev_info, response,
-				     segment_state_running);
-
-	kfree(dev_info->pending_msg_hdr);
-	dev_info->pending_msg_hdr = NULL;
+	chipset_dev->controlvm_payload_bytes_buffered -= ctx->param_bytes;
+	kfree(ctx);
 }
 
-static struct parser_context *
-parser_init_byte_stream(u64 addr, u32 bytes, bool local, bool *retry)
+static struct parser_context *parser_init_stream(u64 addr, u32 bytes,
+						 bool *retry)
 {
-	int allocbytes = sizeof(struct parser_context) + bytes;
+	int allocbytes;
 	struct parser_context *ctx;
+	void *mapping;
 
 	*retry = false;
 
-	/*
-	 * alloc an 0 extra byte to ensure payload is
-	 * '\0'-terminated
-	 */
-	allocbytes++;
+	/* alloc an extra byte to ensure payload is \0 terminated */
+	allocbytes = 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;
@@ -1538,32 +1468,18 @@ parser_init_byte_stream(u64 addr, u32 bytes, bool local, bool *retry)
 
 	ctx->allocbytes = allocbytes;
 	ctx->param_bytes = bytes;
-	ctx->curr = NULL;
-	ctx->bytes_remaining = 0;
-	ctx->byte_stream = false;
-	if (local) {
-		void *p;
-
-		if (addr > virt_to_phys(high_memory - 1))
-			goto err_finish_ctx;
-		p = __va((unsigned long)(addr));
-		memcpy(ctx->data, p, bytes);
-	} else {
-		void *mapping = memremap(addr, bytes, MEMREMAP_WB);
-
-		if (!mapping)
-			goto err_finish_ctx;
-		memcpy(ctx->data, mapping, bytes);
-		memunmap(mapping);
-	}
-
+	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:
-	parser_done(ctx);
+	kfree(ctx);
 	return NULL;
 }
 
@@ -1580,19 +1496,16 @@ err_finish_ctx:
  *		  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)
+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;
-	bool local_addr;
 	struct controlvm_message ackmsg;
 	int err = 0;
 
 	/* create parsing context if necessary */
-	local_addr = (inmsg.hdr.flags.test_message == 1);
 	parm_addr = channel_addr + inmsg.hdr.payload_vm_offset;
 	parm_bytes = inmsg.hdr.payload_bytes;
 
@@ -1601,25 +1514,19 @@ handle_command(struct controlvm_message inmsg, u64 channel_addr)
 	 * within our OS-controlled memory. We need to know that, because it
 	 * makes a difference in how we compute the virtual address.
 	 */
-	if (parm_addr && parm_bytes) {
+	if (parm_bytes) {
 		bool retry = false;
 
-		parser_ctx =
-		    parser_init_byte_stream(parm_addr, parm_bytes,
-					    local_addr, &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;
 
-	if (!local_addr) {
-		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);
@@ -1641,8 +1548,8 @@ handle_command(struct controlvm_message inmsg, u64 channel_addr)
 			err = parahotplug_process_message(&inmsg);
 		} else {
 			/*
-			 * save the hdr and cmd structures for later use
-			 * when sending back the response to Command
+			 * save the hdr and cmd structures for later use when
+			 * sending back the response to Command
 			 */
 			err = visorbus_device_changestate(&inmsg);
 			break;
@@ -1689,12 +1596,9 @@ handle_command(struct controlvm_message inmsg, u64 channel_addr)
  *
  * Return: 0 if valid message was retrieved or -error
  */
-static int
-read_controlvm_event(struct controlvm_message *msg)
+static int read_controlvm_event(struct controlvm_message *msg)
 {
-	int err;
-
-	err = visorchannel_signalremove(chipset_dev->controlvm_channel,
+	int err = visorchannel_signalremove(chipset_dev->controlvm_channel,
 					CONTROLVM_QUEUE_EVENT, msg);
 	if (err)
 		return err;
@@ -1710,8 +1614,7 @@ read_controlvm_event(struct controlvm_message *msg)
  * 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)
+static void parahotplug_process_list(void)
 {
 	struct list_head *pos;
 	struct list_head *tmp;
@@ -1737,8 +1640,7 @@ parahotplug_process_list(void)
 	spin_unlock(&parahotplug_request_list_lock);
 }
 
-static void
-controlvm_periodic_work(struct work_struct *work)
+static void controlvm_periodic_work(struct work_struct *work)
 {
 	struct controlvm_message inmsg;
 	int count = 0;
@@ -1756,9 +1658,8 @@ controlvm_periodic_work(struct work_struct *work)
 
 	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
+		 * 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;
@@ -1793,9 +1694,8 @@ 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
+		 * 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_CONTROLVMCHANNEL_SLOW)
@@ -1812,41 +1712,36 @@ schedule_out:
 			      chipset_dev->poll_jiffies);
 }
 
-static int
-visorchipset_init(struct acpi_device *acpi_device)
+static int visorchipset_init(struct acpi_device *acpi_device)
 {
 	int err = -ENODEV;
-	u64 addr;
-	uuid_le uuid = VISOR_CONTROLVM_CHANNEL_UUID;
 	struct visorchannel *controlvm_channel;
 
 	chipset_dev = kzalloc(sizeof(*chipset_dev), GFP_KERNEL);
 	if (!chipset_dev)
 		goto error;
 
-	addr = controlvm_get_channel_address();
-	if (!addr)
-		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_CONTROLVMCHANNEL_FAST;
-	controlvm_channel = visorchannel_create_with_lock(addr,
-							  0, GFP_KERNEL, uuid);
-
-	if (!controlvm_channel)
-		goto error_free_chipset_dev;
-
-	chipset_dev->controlvm_channel = controlvm_channel;
 
 	err = sysfs_create_groups(&chipset_dev->acpi_device->dev.kobj,
 				  visorchipset_dev_groups);
 	if (err < 0)
 		goto error_destroy_channel;
 
-	if (!VISOR_CONTROLVM_CHANNEL_OK_CLIENT(
-				visorchannel_get_header(controlvm_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))
 		goto error_delete_groups;
 
 	/* if booting in a crash kernel */
@@ -1886,8 +1781,7 @@ error:
 	return err;
 }
 
-static int
-visorchipset_exit(struct acpi_device *acpi_device)
+static int visorchipset_exit(struct acpi_device *acpi_device)
 {
 	visorbus_exit();
 	cancel_delayed_work_sync(&chipset_dev->periodic_controlvm_work);
@@ -1928,9 +1822,8 @@ static __init int visorutil_spar_detect(void)
 		return  (ebx == UNISYS_VISOR_ID_EBX) &&
 			(ecx == UNISYS_VISOR_ID_ECX) &&
 			(edx == UNISYS_VISOR_ID_EDX);
-	} else {
-		return 0;
 	}
+	return 0;
 }
 
 static int init_unisys(void)