staging: unisys: Convert bus creation to use visor_device

This patch removes the legacy bus_info struct and instead creates
and passes around a traditional struct device.

This allows us to remove a lot of the various look up code and
removes the doubt if the struct exists or not.

Half of the churn is just the conversion of visorchipset_bus_info
to visor_device.  Various cleanups include re-arranging the failure
paths to make more sense.
Signed-off-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Benjamin Romer <benjamin.romer@unisys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/unisys/include/visorbus.h

@@ -220,4 +220,7 @@ void visorchannel_debug(struct visorchannel *channel, int num_queues,
 			struct seq_file *seq, u32 off);
 void __iomem *visorchannel_get_header(struct visorchannel *channel);
 
+#define BUS_ROOT_DEVICE		UINT_MAX
+struct visor_device *visorbus_get_device_by_id(u32 bus_no, u32 dev_no,
+					       struct visor_device *from);
 #endif

drivers/staging/unisys/visorbus/visorbus_main.c

@@ -93,8 +93,8 @@ static struct workqueue_struct *periodic_dev_workqueue;
 static long long bus_count;	/** number of bus instances */
 					/** ever-increasing */
 
-static void chipset_bus_create(struct visorchipset_bus_info *bus_info);
-static void chipset_bus_destroy(struct visorchipset_bus_info *bus_info);
+static void chipset_bus_create(struct visor_device *bus_info);
+static void chipset_bus_destroy(struct visor_device *bus_info);
 static void chipset_device_create(struct visorchipset_device_info *dev_info);
 static void chipset_device_destroy(struct visorchipset_device_info *dev_info);
 static void chipset_device_pause(struct visorchipset_device_info *dev_info);
@@ -950,8 +950,7 @@ EXPORT_SYMBOL_GPL(visorbus_disable_channel_interrupts);
  */
 static int
 create_visor_device(struct visor_device *bdev,
-		    struct visorchipset_device_info *dev_info,
-		    u64 partition_handle)
+		    struct visorchipset_device_info *dev_info)
 {
 	int rc = -1;
 	struct visor_device *dev = NULL;
@@ -1161,8 +1160,7 @@ static void
 fix_vbus_dev_info(struct visor_device *visordev)
 {
 	int i;
-	struct visorchipset_bus_info bus_info;
-	struct visor_device *dev = NULL;
+	struct visor_device *bdev;
 	struct visor_driver *visordrv;
 	int bus_no = visordev->chipset_bus_no;
 	int dev_no = visordev->chipset_dev_no;
@@ -1174,17 +1172,14 @@ fix_vbus_dev_info(struct visor_device *visordev)
 			return;
 
 	hdr_info = (struct spar_vbus_headerinfo *)visordev->vbus_hdr_info;
+	if (!hdr_info)
+		return;
 
-	visordrv = to_visor_driver(visordev->device.driver);
-	if (!visorchipset_get_bus_info(bus_no, &bus_info))
-			return;
-
-	dev = (struct visor_device *)(bus_info.bus_driver_context);
-	if (!dev)
-			return;
+	bdev = visorbus_get_device_by_id(bus_no, BUS_ROOT_DEVICE, NULL);
+	if (!bdev)
+		return;
 
-	if (!hdr_info)
-			return;
+	visordrv = to_visor_driver(visordev->device.driver);
 
 	/* Within the list of device types (by GUID) that the driver
 	 * says it supports, find out which one of those types matches
@@ -1203,51 +1198,45 @@ fix_vbus_dev_info(struct visor_device *visordev)
 	bus_device_info_init(&dev_info, chan_type_name,
 			     visordrv->name, visordrv->version,
 			     visordrv->vertag);
-	write_vbus_dev_info(dev->visorchannel, hdr_info, &dev_info, dev_no);
+	write_vbus_dev_info(bdev->visorchannel, hdr_info, &dev_info, dev_no);
 
 	/* Re-write bus+chipset info, because it is possible that this
 	* was previously written by our evil counterpart, virtpci.
 	*/
-	write_vbus_chp_info(dev->visorchannel, hdr_info, &chipset_driverinfo);
-	write_vbus_bus_info(dev->visorchannel, hdr_info, &clientbus_driverinfo);
+	write_vbus_chp_info(bdev->visorchannel, hdr_info, &chipset_driverinfo);
+	write_vbus_bus_info(bdev->visorchannel, hdr_info,
+			    &clientbus_driverinfo);
 }
 
 /** Create a device instance for the visor bus itself.
  */
-static struct visor_device *
-create_bus_instance(struct visorchipset_bus_info *bus_info)
+static int
+create_bus_instance(struct visor_device *dev)
 {
-	struct visor_device *rc = NULL;
-	struct visor_device *dev = NULL;
-	int id = bus_info->bus_no;
+	int rc;
+	int id = dev->chipset_bus_no;
 	struct spar_vbus_headerinfo *hdr_info;
 
 	POSTCODE_LINUX_2(BUS_CREATE_ENTRY_PC, POSTCODE_SEVERITY_INFO);
-	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
-	if (!dev) {
-		POSTCODE_LINUX_2(MALLOC_FAILURE_PC, POSTCODE_SEVERITY_ERR);
-		rc = NULL;
-		goto away;
-	}
 
 	hdr_info = kzalloc(sizeof(*hdr_info), GFP_KERNEL);
 	if (!hdr_info) {
-		rc = NULL;
-		goto away_mem;
+		rc = -1;
+		goto away;
 	}
 
 	dev_set_name(&dev->device, "visorbus%d", id);
 	dev->device.bus = &visorbus_type;
 	dev->device.groups = visorbus_groups;
 	dev->device.release = visorbus_release_busdevice;
+
 	if (device_register(&dev->device) < 0) {
 		POSTCODE_LINUX_3(DEVICE_CREATE_FAILURE_PC, id,
 				 POSTCODE_SEVERITY_ERR);
-		rc = NULL;
-		goto away_mem2;
+		rc = -1;
+		goto away_mem;
 	}
-	dev->chipset_bus_no = id;
-	dev->visorchannel = bus_info->visorchannel;
+
 	if (get_vbus_header_info(dev->visorchannel, hdr_info) >= 0) {
 		dev->vbus_hdr_info = (void *)hdr_info;
 		write_vbus_chp_info(dev->visorchannel, hdr_info,
@@ -1259,16 +1248,11 @@ create_bus_instance(struct visorchipset_bus_info *bus_info)
 	}
 	bus_count++;
 	list_add_tail(&dev->list_all, &list_all_bus_instances);
-	if (id == 0)
-			dev = dev;	/* for testing ONLY */
 	dev_set_drvdata(&dev->device, dev);
-	rc = dev;
-	return rc;
+	return 0;
 
-away_mem2:
-	kfree(hdr_info);
 away_mem:
-	kfree(dev);
+	kfree(hdr_info);
 away:
 	return rc;
 }
@@ -1331,57 +1315,38 @@ remove_all_visor_devices(void)
 }
 
 static void
-chipset_bus_create(struct visorchipset_bus_info *bus_info)
+chipset_bus_create(struct visor_device *dev)
 {
-	struct visor_device *dev;
-	int rc = -1;
-	u32 bus_no = bus_info->bus_no;
+	int rc;
+	u32 bus_no = dev->chipset_bus_no;
 
 	POSTCODE_LINUX_3(BUS_CREATE_ENTRY_PC, bus_no, POSTCODE_SEVERITY_INFO);
-	dev = create_bus_instance(bus_info);
-	if (!dev)
-		goto away;
-	if (!visorchipset_set_bus_context(bus_info, dev))
-		goto away;
+	rc = create_bus_instance(dev);
 	POSTCODE_LINUX_3(BUS_CREATE_EXIT_PC, bus_no, POSTCODE_SEVERITY_INFO);
-	rc = 0;
-away:
-	if (rc < 0) {
+
+	if (rc < 0)
 		POSTCODE_LINUX_3(BUS_CREATE_FAILURE_PC, bus_no,
 				 POSTCODE_SEVERITY_ERR);
-		return;
-	}
-	POSTCODE_LINUX_3(CHIPSET_INIT_SUCCESS_PC, bus_no,
-			 POSTCODE_SEVERITY_INFO);
+	else
+		POSTCODE_LINUX_3(CHIPSET_INIT_SUCCESS_PC, bus_no,
+				 POSTCODE_SEVERITY_INFO);
+
 	if (chipset_responders.bus_create)
-		(*chipset_responders.bus_create) (bus_info, rc);
+		(*chipset_responders.bus_create) (dev, rc);
 }
 
 static void
-chipset_bus_destroy(struct visorchipset_bus_info *bus_info)
+chipset_bus_destroy(struct visor_device *dev)
 {
-	struct visor_device *dev;
-	int rc = -1;
-
-	dev = (struct visor_device *)(bus_info->bus_driver_context);
-	if (!dev)
-		goto away;
 	remove_bus_instance(dev);
-	if (!visorchipset_set_bus_context(bus_info, NULL))
-		goto away;
-	rc = 0;
-away:
-	if (rc < 0)
-		return;
 	if (chipset_responders.bus_destroy)
-		(*chipset_responders.bus_destroy)(bus_info, rc);
+		(*chipset_responders.bus_destroy)(dev, 0);
 }
 
 static void
 chipset_device_create(struct visorchipset_device_info *dev_info)
 {
-	struct visorchipset_bus_info bus_info;
-	struct visor_device *dev = NULL;
+	struct visor_device *bdev;
 	int rc = -1;
 	u32 bus_no = dev_info->bus_no;
 	u32 dev_no = dev_info->dev_no;
@@ -1389,24 +1354,24 @@ chipset_device_create(struct visorchipset_device_info *dev_info)
 	POSTCODE_LINUX_4(DEVICE_CREATE_ENTRY_PC, dev_no, bus_no,
 			 POSTCODE_SEVERITY_INFO);
 
-	if (!visorchipset_get_bus_info(bus_no, &bus_info))
+	bdev = visorbus_get_device_by_id(bus_no, BUS_ROOT_DEVICE, NULL);
+	if (!bdev)
 		goto away;
+
 	POSTCODE_LINUX_4(DEVICE_CREATE_EXIT_PC, dev_no, bus_no,
 			 POSTCODE_SEVERITY_INFO);
-	rc = 0;
+
+	rc = create_visor_device(bdev, dev_info);
 away:
 	if (rc < 0) {
 		POSTCODE_LINUX_4(DEVICE_CREATE_FAILURE_PC, dev_no, bus_no,
 				 POSTCODE_SEVERITY_ERR);
-		return;
+		if (chipset_responders.device_create)
+			(*chipset_responders.device_create)(dev_info, rc);
 	}
-	dev = (struct visor_device *)(bus_info.bus_driver_context);
-	rc = create_visor_device(dev, dev_info, bus_info.partition_handle);
+
 	POSTCODE_LINUX_4(DEVICE_CREATE_SUCCESS_PC, dev_no, bus_no,
 			 POSTCODE_SEVERITY_INFO);
-	if (rc < 0)
-		if (chipset_responders.device_create)
-			(*chipset_responders.device_create)(dev_info, rc);
 }
 
 static void

drivers/staging/unisys/visorbus/visorbus_private.h

@@ -49,35 +49,13 @@ struct visorchipset_device_info {
 	void *bus_driver_context;
 };
 
-/** Attributes for a particular Supervisor bus.
- *  (For a service partition acting as the server for buses/devices, there
- *  is a 1-to-1 relationship between busses and guest partitions.)
- *  Any visorchipset client can query these attributes using
- *  visorchipset_get_client_bus_info() or visorchipset_get_bus_info().
- */
-struct visorchipset_bus_info {
-	struct list_head entry;
-	u32 bus_no;
-	struct visorchipset_state state;
-	struct visorchannel *visorchannel;
-	uuid_le partition_uuid;
-	u64 partition_handle;
-	u8 *name;		/* UTF8 */
-	u8 *description;	/* UTF8 */
-	u64 reserved1;
-	u32 reserved2;
-	struct controlvm_message_header *pending_msg_hdr;/* CONTROLVM MsgHdr */
-	/** For private use by the bus driver */
-	void *bus_driver_context;
-};
-
 /*  These functions will be called from within visorchipset when certain
  *  events happen.  (The implementation of these functions is outside of
  *  visorchipset.)
  */
 struct visorchipset_busdev_notifiers {
-	void (*bus_create)(struct visorchipset_bus_info *bus_info);
-	void (*bus_destroy)(struct visorchipset_bus_info *bus_info);
+	void (*bus_create)(struct visor_device *bus_info);
+	void (*bus_destroy)(struct visor_device *bus_info);
 	void (*device_create)(struct visorchipset_device_info *bus_info);
 	void (*device_destroy)(struct visorchipset_device_info *bus_info);
 	void (*device_pause)(struct visorchipset_device_info *bus_info);
@@ -91,8 +69,8 @@ struct visorchipset_busdev_notifiers {
  *      -1 = it failed
  */
 struct visorchipset_busdev_responders {
-	void (*bus_create)(struct visorchipset_bus_info *p, int response);
-	void (*bus_destroy)(struct visorchipset_bus_info *p, int response);
+	void (*bus_create)(struct visor_device *p, int response);
+	void (*bus_destroy)(struct visor_device *p, int response);
 	void (*device_create)(struct visorchipset_device_info *p, int response);
 	void (*device_destroy)(struct visorchipset_device_info *p,
 			       int response);
@@ -112,10 +90,10 @@ visorchipset_register_busdev(
 			struct ultra_vbus_deviceinfo *driver_info);
 
 bool visorchipset_get_bus_info(u32 bus_no,
-			       struct visorchipset_bus_info *bus_info);
+			       struct visor_device *bus_info);
 bool visorchipset_get_device_info(u32 bus_no, u32 dev_no,
 				  struct visorchipset_device_info *dev_info);
-bool visorchipset_set_bus_context(struct visorchipset_bus_info *bus_info,
+bool visorchipset_set_bus_context(struct visor_device *bus_info,
 				  void *context);
 
 /* visorbus init and exit functions */

drivers/staging/unisys/visorbus/visorchipset.c

@@ -56,8 +56,6 @@
 #define UNISYS_SPAR_ID_ECX 0x70537379
 #define UNISYS_SPAR_ID_EDX 0x34367261
 
-#define BUS_ROOT_DEVICE	UINT_MAX
-
 /*
  * Module parameters
  */
@@ -230,8 +228,8 @@ static void parahotplug_process_list(void);
  */
 static struct visorchipset_busdev_notifiers busdev_notifiers;
 
-static void bus_create_response(struct visorchipset_bus_info *p, int response);
-static void bus_destroy_response(struct visorchipset_bus_info *p, int response);
+static void bus_create_response(struct visor_device *p, int response);
+static void bus_destroy_response(struct visor_device *p, int response);
 static void device_create_response(struct visorchipset_device_info *p,
 				   int response);
 static void device_destroy_response(struct visorchipset_device_info *p,
@@ -698,16 +696,6 @@ static ssize_t remaining_steps_store(struct device *dev,
 	return count;
 }
 
-static void
-bus_info_clear(void *v)
-{
-	struct visorchipset_bus_info *p = (struct visorchipset_bus_info *) v;
-
-	kfree(p->name);
-	kfree(p->description);
-	memset(p, 0, sizeof(struct visorchipset_bus_info));
-}
-
 static void
 dev_info_clear(void *v)
 {
@@ -756,19 +744,6 @@ struct visor_device *visorbus_get_device_by_id(u32 bus_no, u32 dev_no,
 }
 EXPORT_SYMBOL(visorbus_get_device_by_id);
 
-static struct visorchipset_bus_info *
-bus_find(struct list_head *list, u32 bus_no)
-{
-	struct visorchipset_bus_info *p;
-
-	list_for_each_entry(p, list, entry) {
-		if (p->bus_no == bus_no)
-			return p;
-	}
-
-	return NULL;
-}
-
 static struct visorchipset_device_info *
 device_find(struct list_head *list, u32 bus_no, u32 dev_no)
 {
@@ -842,15 +817,8 @@ EXPORT_SYMBOL_GPL(visorchipset_register_busdev);
 static void
 cleanup_controlvm_structures(void)
 {
-	struct visorchipset_bus_info *bi, *tmp_bi;
 	struct visorchipset_device_info *di, *tmp_di;
 
-	list_for_each_entry_safe(bi, tmp_bi, &bus_info_list, entry) {
-		bus_info_clear(bi);
-		list_del(&bi->entry);
-		kfree(bi);
-	}
-
 	list_for_each_entry_safe(di, tmp_di, &dev_info_list, entry) {
 		dev_info_clear(di);
 		list_del(&di->entry);
@@ -1017,7 +985,7 @@ device_responder(enum controlvm_id cmd_id,
 }
 
 static void
-bus_epilog(struct visorchipset_bus_info *bus_info,
+bus_epilog(struct visor_device *bus_info,
 	   u32 cmd, struct controlvm_message_header *msg_hdr,
 	   int response, bool need_response)
 {
@@ -1207,10 +1175,10 @@ bus_create(struct controlvm_message *inmsg)
 	struct controlvm_message_packet *cmd = &inmsg->cmd;
 	u32 bus_no = cmd->create_bus.bus_no;
 	int rc = CONTROLVM_RESP_SUCCESS;
-	struct visorchipset_bus_info *bus_info;
+	struct visor_device *bus_info;
 	struct visorchannel *visorchannel;
 
-	bus_info = bus_find(&bus_info_list, bus_no);
+	bus_info = visorbus_get_device_by_id(bus_no, BUS_ROOT_DEVICE, NULL);
 	if (bus_info && (bus_info->state.created == 1)) {
 		POSTCODE_LINUX_3(BUS_CREATE_FAILURE_PC, bus_no,
 				 POSTCODE_SEVERITY_ERR);
@@ -1225,8 +1193,8 @@ bus_create(struct controlvm_message *inmsg)
 		goto cleanup;
 	}
 
-	INIT_LIST_HEAD(&bus_info->entry);
-	bus_info->bus_no = bus_no;
+	bus_info->chipset_bus_no = bus_no;
+	bus_info->chipset_dev_no = BUS_ROOT_DEVICE;
 
 	POSTCODE_LINUX_3(BUS_CREATE_ENTRY_PC, bus_no, POSTCODE_SEVERITY_INFO);
 
@@ -1244,7 +1212,6 @@ bus_create(struct controlvm_message *inmsg)
 		goto cleanup;
 	}
 	bus_info->visorchannel = visorchannel;
-	list_add(&bus_info->entry, &bus_info_list);
 
 	POSTCODE_LINUX_3(BUS_CREATE_EXIT_PC, bus_no, POSTCODE_SEVERITY_INFO);
 
@@ -1258,10 +1225,10 @@ bus_destroy(struct controlvm_message *inmsg)
 {
 	struct controlvm_message_packet *cmd = &inmsg->cmd;
 	u32 bus_no = cmd->destroy_bus.bus_no;
-	struct visorchipset_bus_info *bus_info;
+	struct visor_device *bus_info;
 	int rc = CONTROLVM_RESP_SUCCESS;
 
-	bus_info = bus_find(&bus_info_list, bus_no);
+	bus_info = visorbus_get_device_by_id(bus_no, BUS_ROOT_DEVICE, NULL);
 	if (!bus_info)
 		rc = -CONTROLVM_RESP_ERROR_BUS_INVALID;
 	else if (bus_info->state.created == 0)
@@ -1269,6 +1236,8 @@ bus_destroy(struct controlvm_message *inmsg)
 
 	bus_epilog(bus_info, CONTROLVM_BUS_DESTROY, &inmsg->hdr,
 		   rc, inmsg->hdr.flags.response_expected == 1);
+
+	/* bus_info is freed as part of the busdevice_release function */
 }
 
 static void
@@ -1277,15 +1246,14 @@ bus_configure(struct controlvm_message *inmsg,
 {
 	struct controlvm_message_packet *cmd = &inmsg->cmd;
 	u32 bus_no;
-	struct visorchipset_bus_info *bus_info;
+	struct visor_device *bus_info;
 	int rc = CONTROLVM_RESP_SUCCESS;
-	char s[99];
 
 	bus_no = cmd->configure_bus.bus_no;
 	POSTCODE_LINUX_3(BUS_CONFIGURE_ENTRY_PC, bus_no,
 			 POSTCODE_SEVERITY_INFO);
 
-	bus_info = bus_find(&bus_info_list, bus_no);
+	bus_info = visorbus_get_device_by_id(bus_no, BUS_ROOT_DEVICE, NULL);
 	if (!bus_info) {
 		POSTCODE_LINUX_3(BUS_CONFIGURE_FAILURE_PC, bus_no,
 				 POSTCODE_SEVERITY_ERR);
@@ -1305,7 +1273,6 @@ bus_configure(struct controlvm_message *inmsg,
 		parser_param_start(parser_ctx, PARSERSTRING_NAME);
 		bus_info->name = parser_string_get(parser_ctx);
 
-		visorchannel_uuid_id(&bus_info->partition_uuid, s);
 		POSTCODE_LINUX_3(BUS_CONFIGURE_EXIT_PC, bus_no,
 				 POSTCODE_SEVERITY_INFO);
 	}
@@ -1320,7 +1287,7 @@ my_device_create(struct controlvm_message *inmsg)
 	u32 bus_no = cmd->create_device.bus_no;
 	u32 dev_no = cmd->create_device.dev_no;
 	struct visorchipset_device_info *dev_info;
-	struct visorchipset_bus_info *bus_info;
+	struct visor_device *bus_info;
 	struct visorchannel *visorchannel;
 	int rc = CONTROLVM_RESP_SUCCESS;
 
@@ -1331,7 +1298,7 @@ my_device_create(struct controlvm_message *inmsg)
 		rc = -CONTROLVM_RESP_ERROR_ALREADY_DONE;
 		goto cleanup;
 	}
-	bus_info = bus_find(&bus_info_list, bus_no);
+	bus_info = visorbus_get_device_by_id(bus_no, dev_no, NULL);
 	if (!bus_info) {
 		POSTCODE_LINUX_4(DEVICE_CREATE_FAILURE_PC, dev_no, bus_no,
 				 POSTCODE_SEVERITY_ERR);
@@ -2134,14 +2101,15 @@ setup_crash_devices_work_queue(struct work_struct *work)
 }
 
 static void
-bus_create_response(struct visorchipset_bus_info *bus_info, int response)
+bus_create_response(struct visor_device *bus_info, int response)
 {
 	if (response >= 0) {
 		bus_info->state.created = 1;
 	} else {
 		if (response != -CONTROLVM_RESP_ERROR_ALREADY_DONE)
 			/* undo the row we just created... */
-			busdevices_del(&dev_info_list, bus_info->bus_no);
+			busdevices_del(&dev_info_list,
+				       bus_info->chipset_bus_no);
 	}
 
 	bus_responder(CONTROLVM_BUS_CREATE, bus_info->pending_msg_hdr,
@@ -2152,7 +2120,7 @@ bus_create_response(struct visorchipset_bus_info *bus_info, int response)
 }
 
 static void
-bus_destroy_response(struct visorchipset_bus_info *bus_info, int response)
+bus_destroy_response(struct visor_device *bus_info, int response)
 {
 	bus_responder(CONTROLVM_BUS_DESTROY, bus_info->pending_msg_hdr,
 		      response);
@@ -2160,8 +2128,7 @@ bus_destroy_response(struct visorchipset_bus_info *bus_info, int response)
 	kfree(bus_info->pending_msg_hdr);
 	bus_info->pending_msg_hdr = NULL;
 
-	bus_info_clear(bus_info);
-	busdevices_del(&dev_info_list, bus_info->bus_no);
+	busdevices_del(&dev_info_list, bus_info->chipset_bus_no);
 }
 
 static void
@@ -2212,28 +2179,6 @@ device_resume_response(struct visorchipset_device_info *dev_info, int response)
 	dev_info->pending_msg_hdr = NULL;
 }
 
-bool
-visorchipset_get_bus_info(u32 bus_no, struct visorchipset_bus_info *bus_info)
-{
-	void *p = bus_find(&bus_info_list, bus_no);
-
-	if (!p)
-		return false;
-	memcpy(bus_info, p, sizeof(struct visorchipset_bus_info));
-	return true;
-}
-EXPORT_SYMBOL_GPL(visorchipset_get_bus_info);
-
-bool
-visorchipset_set_bus_context(struct visorchipset_bus_info *p, void *context)
-{
-	if (!p)
-		return false;
-	p->bus_driver_context = context;
-	return true;
-}
-EXPORT_SYMBOL_GPL(visorchipset_set_bus_context);
-
 bool
 visorchipset_get_device_info(u32 bus_no, u32 dev_no,
 			     struct visorchipset_device_info *dev_info)