[PATCH v4 23/29] staging: unisys: visorbus: Remove notifier-related code from visorbus

From: David Kershner
Date: Wed Jun 08 2016 - 17:21:37 EST

From: David Binder <david.binder@xxxxxxxxxx>

When this functionality was first implemented, visorchipset and visorbus
were separate drivers, which necessitated a registration mechanism for
them to communicate. More-recently, visorchipset and visorbus were
combined into a single driver, and now exist as separate source files
within the same driver, known as 'visorbus'. This eliminated the need
for a registration mechanism, but it has remained nevertheless until now.
For the sake of simplification, this registration mechanism is now being
removed.

Signed-off-by: David Binder <david.binder@xxxxxxxxxx>
Signed-off-by: David Kershner <david.kershner@xxxxxxxxxx>
Reviewed-by: Tim Sell <timothy.sell@xxxxxxxxxx>
---
drivers/staging/unisys/visorbus/visorbus_main.c | 76 +++---------
drivers/staging/unisys/visorbus/visorbus_private.h | 50 +++-----
drivers/staging/unisys/visorbus/visorchipset.c | 130 ++++-----------------
3 files changed, 50 insertions(+), 206 deletions(-)

diff --git a/drivers/staging/unisys/visorbus/visorbus_main.c b/drivers/staging/unisys/visorbus/visorbus_main.c
index 2468264..c361077 100644
--- a/drivers/staging/unisys/visorbus/visorbus_main.c
+++ b/drivers/staging/unisys/visorbus/visorbus_main.c
@@ -119,32 +119,6 @@ struct bus_type visorbus_type = {
static long long bus_count; /* number of bus instances */
/* ever-increasing */

-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 visor_device *dev_info);
-static void chipset_device_destroy(struct visor_device *dev_info);
-static void chipset_device_pause(struct visor_device *dev_info);
-static void chipset_device_resume(struct visor_device *dev_info);
-
-/*
- * These functions are implemented herein, and are called by the chipset
- * driver to notify us about specific events.
- */
-static struct visorchipset_busdev_notifiers chipset_notifiers = {
- .bus_create = chipset_bus_create,
- .bus_destroy = chipset_bus_destroy,
- .device_create = chipset_device_create,
- .device_destroy = chipset_device_destroy,
- .device_pause = chipset_device_pause,
- .device_resume = chipset_device_resume,
-};
-
-/*
- * These functions are implemented in the chipset driver, and we call them
- * herein when we want to acknowledge a specific event.
- */
-static struct visorchipset_busdev_responders chipset_responders;
-
/* filled in with info about parent chipset driver when we register with it */
static struct ultra_vbus_deviceinfo chipset_driverinfo;
/* filled in with info about this driver, wrt it servicing client busses */
@@ -1171,7 +1145,7 @@ remove_all_visor_devices(void)
}
}

-static void
+void
chipset_bus_create(struct visor_device *dev)
{
int rc;
@@ -1188,19 +1162,17 @@ chipset_bus_create(struct visor_device *dev)
POSTCODE_LINUX_3(CHIPSET_INIT_SUCCESS_PC, bus_no,
POSTCODE_SEVERITY_INFO);

- if (chipset_responders.bus_create)
- (*chipset_responders.bus_create) (dev, rc);
+ bus_create_response(dev, rc);
}

-static void
+void
chipset_bus_destroy(struct visor_device *dev)
{
remove_bus_instance(dev);
- if (chipset_responders.bus_destroy)
- (*chipset_responders.bus_destroy)(dev, 0);
+ bus_destroy_response(dev, 0);
}

-static void
+void
chipset_device_create(struct visor_device *dev_info)
{
int rc;
@@ -1211,8 +1183,7 @@ chipset_device_create(struct visor_device *dev_info)
POSTCODE_SEVERITY_INFO);

rc = create_visor_device(dev_info);
- if (chipset_responders.device_create)
- chipset_responders.device_create(dev_info, rc);
+ device_create_response(dev_info, rc);

if (rc < 0)
POSTCODE_LINUX_4(DEVICE_CREATE_FAILURE_PC, dev_no, bus_no,
@@ -1222,13 +1193,12 @@ chipset_device_create(struct visor_device *dev_info)
POSTCODE_SEVERITY_INFO);
}

-static void
+void
chipset_device_destroy(struct visor_device *dev_info)
{
remove_visor_device(dev_info);

- if (chipset_responders.device_destroy)
- (*chipset_responders.device_destroy) (dev_info, 0);
+ device_destroy_response(dev_info, 0);
}

/**
@@ -1247,14 +1217,8 @@ pause_state_change_complete(struct visor_device *dev, int status)
return;

dev->pausing = false;
- if (!chipset_responders.device_pause) /* this can never happen! */
- return;

- /* Notify the chipset driver that the pause is complete, which
- * will presumably want to send some sort of response to the
- * initiator.
- */
- (*chipset_responders.device_pause) (dev, status);
+ visorchipset_device_pause_response(dev, status);
}

/**
@@ -1273,15 +1237,13 @@ resume_state_change_complete(struct visor_device *dev, int status)
return;

dev->resuming = false;
- if (!chipset_responders.device_resume) /* this can never happen! */
- return;

/*
* Notify the chipset driver that the resume is complete,
* which will presumably want to send some sort of response to
* the initiator.
*/
- (*chipset_responders.device_resume) (dev, status);
+ device_resume_response(dev, status);
}

/**
@@ -1303,9 +1265,9 @@ initiate_chipset_device_pause_resume(struct visor_device *dev, bool is_pause)
void (*notify_func)(struct visor_device *dev, int response) = NULL;

if (is_pause)
- notify_func = chipset_responders.device_pause;
+ notify_func = visorchipset_device_pause_response;
else
- notify_func = chipset_responders.device_resume;
+ notify_func = device_resume_response;
if (!notify_func)
return;

@@ -1369,7 +1331,7 @@ initiate_chipset_device_pause_resume(struct visor_device *dev, bool is_pause)
* that device. Success/failure result is returned asynchronously
* via a callback function; see pause_state_change_complete().
*/
-static void
+void
chipset_device_pause(struct visor_device *dev_info)
{
initiate_chipset_device_pause_resume(dev_info, true);
@@ -1383,7 +1345,7 @@ chipset_device_pause(struct visor_device *dev_info)
* that device. Success/failure result is returned asynchronously
* via a callback function; see resume_state_change_complete().
*/
-static void
+void
chipset_device_resume(struct visor_device *dev_info)
{
initiate_chipset_device_pause_resume(dev_info, false);
@@ -1405,12 +1367,9 @@ visorbus_init(void)
goto error;
}

- /* This enables us to receive notifications when devices appear for
- * which this service partition is to be a server for.
- */
- visorchipset_register_busdev(&chipset_notifiers,
- &chipset_responders,
- &chipset_driverinfo);
+ bus_device_info_init(&chipset_driverinfo,
+ "chipset", "visorchipset",
+ VERSION, NULL);

return 0;

@@ -1424,7 +1383,6 @@ visorbus_exit(void)
{
struct list_head *listentry, *listtmp;

- visorchipset_register_busdev(NULL, NULL, NULL);
remove_all_visor_devices();

list_for_each_safe(listentry, listtmp, &list_all_bus_instances) {
diff --git a/drivers/staging/unisys/visorbus/visorbus_private.h b/drivers/staging/unisys/visorbus/visorbus_private.h
index 31b5ca9..3b5a8f2 100644
--- a/drivers/staging/unisys/visorbus/visorbus_private.h
+++ b/drivers/staging/unisys/visorbus/visorbus_private.h
@@ -23,44 +23,20 @@
#include "vbusdeviceinfo.h"
#include "vbushelper.h"

-/* 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 visor_device *bus_info);
- void (*bus_destroy)(struct visor_device *bus_info);
- void (*device_create)(struct visor_device *bus_info);
- void (*device_destroy)(struct visor_device *bus_info);
- void (*device_pause)(struct visor_device *bus_info);
- void (*device_resume)(struct visor_device *bus_info);
-};
-
-/* These functions live inside visorchipset, and will be called to indicate
- * responses to specific events (by code outside of visorchipset).
- * For now, the value for each response is simply either:
- * 0 = it worked
- * -1 = it failed
- */
-struct visorchipset_busdev_responders {
- void (*bus_create)(struct visor_device *p, int response);
- void (*bus_destroy)(struct visor_device *p, int response);
- void (*device_create)(struct visor_device *p, int response);
- void (*device_destroy)(struct visor_device *p, int response);
- void (*device_pause)(struct visor_device *p, int response);
- void (*device_resume)(struct visor_device *p, int response);
-};
+void chipset_bus_create(struct visor_device *bus_info);
+void chipset_bus_destroy(struct visor_device *bus_info);
+void chipset_device_create(struct visor_device *dev_info);
+void chipset_device_destroy(struct visor_device *dev_info);
+void chipset_device_pause(struct visor_device *dev_info);
+void chipset_device_resume(struct visor_device *dev_info);

-/** Register functions (in the bus driver) to get called by visorchipset
- * whenever a bus or device appears for which this guest is to be the
- * client for. visorchipset will fill in <responders>, to indicate
- * functions the bus driver should call to indicate message responses.
- */
-void
-visorchipset_register_busdev(
- struct visorchipset_busdev_notifiers *notifiers,
- struct visorchipset_busdev_responders *responders,
- struct ultra_vbus_deviceinfo *driver_info);
+void bus_create_response(struct visor_device *p, int response);
+void bus_destroy_response(struct visor_device *p, int response);
+void device_create_response(struct visor_device *p, int response);
+void device_destroy_response(struct visor_device *p, int response);
+void device_resume_response(struct visor_device *p, int response);
+void visorchipset_device_pause_response(struct visor_device *p,
+ int response);

/* visorbus init and exit functions */
int visorbus_init(void);
diff --git a/drivers/staging/unisys/visorbus/visorchipset.c b/drivers/staging/unisys/visorbus/visorchipset.c
index f8e1fa5..ea548df 100644
--- a/drivers/staging/unisys/visorbus/visorchipset.c
+++ b/drivers/staging/unisys/visorbus/visorchipset.c
@@ -87,7 +87,6 @@ visorchipset_release(struct inode *inode, struct file *file)
static unsigned long poll_jiffies = POLLJIFFIES_CONTROLVMCHANNEL_FAST;
/* when we got our last controlvm message */
static unsigned long most_recent_message_jiffies;
-static int visorbusregistered;

struct parser_context {
unsigned long allocbytes;
@@ -99,7 +98,6 @@ struct parser_context {
};

static struct delayed_work periodic_controlvm_work;
-static DEFINE_SEMAPHORE(notifier_lock);

static struct cdev file_cdev;
static struct visorchannel **file_controlvm_channel;
@@ -212,26 +210,6 @@ static LIST_HEAD(parahotplug_request_list);
static DEFINE_SPINLOCK(parahotplug_request_list_lock); /* lock for above */
static void parahotplug_process_list(void);

-static struct visorchipset_busdev_notifiers busdev_notifiers;
-
-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 visor_device *p, int response);
-static void device_destroy_response(struct visor_device *p, int response);
-static void device_resume_response(struct visor_device *p, int response);
-
-static void visorchipset_device_pause_response(struct visor_device *p,
- int response);
-
-static struct visorchipset_busdev_responders busdev_responders = {
- .bus_create = bus_create_response,
- .bus_destroy = bus_destroy_response,
- .device_create = device_create_response,
- .device_destroy = device_destroy_response,
- .device_pause = visorchipset_device_pause_response,
- .device_resume = device_resume_response,
-};
-
/* info for /dev/visorchipset */
static dev_t major_dev = -1; /*< indicates major num for device */

@@ -691,30 +669,6 @@ struct visor_device *visorbus_get_device_by_id(u32 bus_no, u32 dev_no,
return vdev;
}

-void
-visorchipset_register_busdev(
- struct visorchipset_busdev_notifiers *notifiers,
- struct visorchipset_busdev_responders *responders,
- struct ultra_vbus_deviceinfo *driver_info)
-{
- down(&notifier_lock);
- if (!notifiers) {
- memset(&busdev_notifiers, 0,
- sizeof(busdev_notifiers));
- visorbusregistered = 0; /* clear flag */
- } else {
- busdev_notifiers = *notifiers;
- visorbusregistered = 1; /* set flag */
- }
- if (responders)
- *responders = busdev_responders;
- if (driver_info)
- bus_device_info_init(driver_info, "chipset", "visorchipset",
- VERSION, NULL);
-
- up(&notifier_lock);
-}
-
static void
chipset_init(struct controlvm_message *inmsg)
{
@@ -927,22 +881,20 @@ bus_epilog(struct visor_device *bus_info,
{
struct controlvm_message_header *pmsg_hdr = NULL;

- down(&notifier_lock);
-
if (!bus_info) {
/*
* relying on a valid passed in response code
* be lazy and re-use msg_hdr for this failure, is this ok??
*/
pmsg_hdr = msg_hdr;
- goto out_respond_and_unlock;
+ goto out_respond;
}

if (bus_info->pending_msg_hdr) {
/* only non-NULL if dev is still waiting on a response */
response = -CONTROLVM_RESP_ERROR_MESSAGE_ID_INVALID_FOR_CLIENT;
pmsg_hdr = bus_info->pending_msg_hdr;
- goto out_respond_and_unlock;
+ goto out_respond;
}

if (need_response) {
@@ -951,7 +903,7 @@ bus_epilog(struct visor_device *bus_info,
POSTCODE_LINUX_4(MALLOC_FAILURE_PC, cmd,
bus_info->chipset_bus_no,
POSTCODE_SEVERITY_ERR);
- goto out_unlock;
+ return;
}

memcpy(pmsg_hdr, msg_hdr,
@@ -962,25 +914,16 @@ bus_epilog(struct visor_device *bus_info,
if (response == CONTROLVM_RESP_SUCCESS) {
switch (cmd) {
case CONTROLVM_BUS_CREATE:
- if (busdev_notifiers.bus_create) {
- (*busdev_notifiers.bus_create) (bus_info);
- goto out_unlock;
- }
+ chipset_bus_create(bus_info);
break;
case CONTROLVM_BUS_DESTROY:
- if (busdev_notifiers.bus_destroy) {
- (*busdev_notifiers.bus_destroy) (bus_info);
- goto out_unlock;
- }
+ chipset_bus_destroy(bus_info);
break;
}
}

-out_respond_and_unlock:
+out_respond:
bus_responder(cmd, pmsg_hdr, response);
-
-out_unlock:
- up(&notifier_lock);
}

static void
@@ -989,33 +932,29 @@ device_epilog(struct visor_device *dev_info,
struct controlvm_message_header *msg_hdr, int response,
bool need_response, bool for_visorbus)
{
- struct visorchipset_busdev_notifiers *notifiers;
struct controlvm_message_header *pmsg_hdr = NULL;

- notifiers = &busdev_notifiers;
-
- down(&notifier_lock);
if (!dev_info) {
/*
* relying on a valid passed in response code
* be lazy and re-use msg_hdr for this failure, is this ok??
*/
pmsg_hdr = msg_hdr;
- goto out_respond_and_unlock;
+ goto out_respond;
}

if (dev_info->pending_msg_hdr) {
/* only non-NULL if dev is still waiting on a response */
response = -CONTROLVM_RESP_ERROR_MESSAGE_ID_INVALID_FOR_CLIENT;
pmsg_hdr = dev_info->pending_msg_hdr;
- goto out_respond_and_unlock;
+ goto out_respond;
}

if (need_response) {
pmsg_hdr = kzalloc(sizeof(*pmsg_hdr), GFP_KERNEL);
if (!pmsg_hdr) {
response = -CONTROLVM_RESP_ERROR_KMALLOC_FAILED;
- goto out_respond_and_unlock;
+ goto out_respond;
}

memcpy(pmsg_hdr, msg_hdr,
@@ -1026,20 +965,14 @@ device_epilog(struct visor_device *dev_info,
if (response >= 0) {
switch (cmd) {
case CONTROLVM_DEVICE_CREATE:
- if (notifiers->device_create) {
- (*notifiers->device_create) (dev_info);
- goto out_unlock;
- }
+ chipset_device_create(dev_info);
break;
case CONTROLVM_DEVICE_CHANGESTATE:
/* ServerReady / ServerRunning / SegmentStateRunning */
if (state.alive == segment_state_running.alive &&
state.operating ==
segment_state_running.operating) {
- if (notifiers->device_resume) {
- (*notifiers->device_resume) (dev_info);
- goto out_unlock;
- }
+ chipset_device_resume(dev_info);
}
/* ServerNotReady / ServerLost / SegmentStateStandby */
else if (state.alive == segment_state_standby.alive &&
@@ -1049,26 +982,17 @@ device_epilog(struct visor_device *dev_info,
* technically this is standby case
* where server is lost
*/
- if (notifiers->device_pause) {
- (*notifiers->device_pause) (dev_info);
- goto out_unlock;
- }
+ chipset_device_pause(dev_info);
}
break;
case CONTROLVM_DEVICE_DESTROY:
- if (notifiers->device_destroy) {
- (*notifiers->device_destroy) (dev_info);
- goto out_unlock;
- }
+ chipset_device_destroy(dev_info);
break;
}
}

-out_respond_and_unlock:
+out_respond:
device_responder(cmd, pmsg_hdr, response);
-
-out_unlock:
- up(&notifier_lock);
}

static void
@@ -1866,10 +1790,6 @@ controlvm_periodic_work(struct work_struct *work)
bool got_command = false;
bool handle_command_failed = false;

- /* make sure visorbus server is registered for controlvm callbacks */
- if (visorchipset_visorbusregwait && !visorbusregistered)
- goto cleanup;
-
while (visorchannel_signalremove(controlvm_channel,
CONTROLVM_QUEUE_RESPONSE,
&inmsg))
@@ -1913,8 +1833,6 @@ controlvm_periodic_work(struct work_struct *work)
/* parahotplug_worker */
parahotplug_process_list();

-cleanup:
-
if (time_after(jiffies,
most_recent_message_jiffies + (HZ * MIN_IDLE_SECONDS))) {
/*
@@ -1941,13 +1859,6 @@ setup_crash_devices_work_queue(struct work_struct *work)
u32 local_crash_msg_offset;
u16 local_crash_msg_count;

- /* make sure visorbus is registered for controlvm callbacks */
- if (visorchipset_visorbusregwait && !visorbusregistered) {
- poll_jiffies = POLLJIFFIES_CONTROLVMCHANNEL_SLOW;
- schedule_delayed_work(&periodic_controlvm_work, poll_jiffies);
- return;
- }
-
POSTCODE_LINUX_2(CRASH_DEV_ENTRY_PC, POSTCODE_SEVERITY_INFO);

/* send init chipset msg */
@@ -2025,7 +1936,7 @@ setup_crash_devices_work_queue(struct work_struct *work)
POSTCODE_LINUX_2(CRASH_DEV_EXIT_PC, POSTCODE_SEVERITY_INFO);
}

-static void
+void
bus_create_response(struct visor_device *bus_info, int response)
{
if (response >= 0)
@@ -2038,7 +1949,7 @@ bus_create_response(struct visor_device *bus_info, int response)
bus_info->pending_msg_hdr = NULL;
}

-static void
+void
bus_destroy_response(struct visor_device *bus_info, int response)
{
bus_responder(CONTROLVM_BUS_DESTROY, bus_info->pending_msg_hdr,
@@ -2048,7 +1959,7 @@ bus_destroy_response(struct visor_device *bus_info, int response)
bus_info->pending_msg_hdr = NULL;
}

-static void
+void
device_create_response(struct visor_device *dev_info, int response)
{
if (response >= 0)
@@ -2061,7 +1972,7 @@ device_create_response(struct visor_device *dev_info, int response)
dev_info->pending_msg_hdr = NULL;
}

-static void
+void
device_destroy_response(struct visor_device *dev_info, int response)
{
device_responder(CONTROLVM_DEVICE_DESTROY, dev_info->pending_msg_hdr,
@@ -2071,7 +1982,7 @@ device_destroy_response(struct visor_device *dev_info, int response)
dev_info->pending_msg_hdr = NULL;
}

-static void
+void
visorchipset_device_pause_response(struct visor_device *dev_info,
int response)
{
@@ -2083,7 +1994,7 @@ visorchipset_device_pause_response(struct visor_device *dev_info,
dev_info->pending_msg_hdr = NULL;
}

-static void
+void
device_resume_response(struct visor_device *dev_info, int response)
{
device_changestate_responder(CONTROLVM_DEVICE_CHANGESTATE,
@@ -2290,7 +2201,6 @@ visorchipset_init(struct acpi_device *acpi_device)
if (!addr)
goto error;

- memset(&busdev_notifiers, 0, sizeof(busdev_notifiers));
memset(&controlvm_payload_info, 0, sizeof(controlvm_payload_info));

controlvm_channel = visorchannel_create_with_lock(addr, 0,
--
1.9.1