[PATCH 3/3] dax-device: Make remove callback return void

From: Uwe Kleine-König
Date: Wed Jan 27 2021 - 18:07:15 EST


The driver core ignores the return value of struct bus_type::remove()
because there is only little that can be done. To simplify the quest to
make this function return void, let struct dax_device_driver::remove()
return void, too. All users already unconditionally return 0, this commit
makes it obvious that returning an error code is a bad idea and makes it
obvious for future driver authors that returning an error code isn't
intended.

Signed-off-by: Uwe Kleine-König <uwe@xxxxxxxxxxxxxxxxx>
---
drivers/dax/bus.c | 4 +++-
drivers/dax/bus.h | 2 +-
drivers/dax/device.c | 3 +--
drivers/dax/kmem.c | 7 ++-----
4 files changed, 7 insertions(+), 9 deletions(-)

diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c
index 498c60333d60..253f37a61371 100644
--- a/drivers/dax/bus.c
+++ b/drivers/dax/bus.c
@@ -179,7 +179,9 @@ static int dax_bus_remove(struct device *dev)
struct dax_device_driver *dax_drv = to_dax_drv(dev->driver);
struct dev_dax *dev_dax = to_dev_dax(dev);

- return dax_drv->remove(dev_dax);
+ dax_drv->remove(dev_dax);
+
+ return 0;
}

static struct bus_type dax_bus_type = {
diff --git a/drivers/dax/bus.h b/drivers/dax/bus.h
index 72b92f95509f..1e946ad7780a 100644
--- a/drivers/dax/bus.h
+++ b/drivers/dax/bus.h
@@ -39,7 +39,7 @@ struct dax_device_driver {
struct list_head ids;
int match_always;
int (*probe)(struct dev_dax *dev);
- int (*remove)(struct dev_dax *dev);
+ void (*remove)(struct dev_dax *dev);
};

int __dax_driver_register(struct dax_device_driver *dax_drv,
diff --git a/drivers/dax/device.c b/drivers/dax/device.c
index 5da2980bb16b..d532c885f574 100644
--- a/drivers/dax/device.c
+++ b/drivers/dax/device.c
@@ -452,10 +452,9 @@ int dev_dax_probe(struct dev_dax *dev_dax)
}
EXPORT_SYMBOL_GPL(dev_dax_probe);

-static int dev_dax_remove(struct dev_dax *dev_dax)
+static void dev_dax_remove(struct dev_dax *dev_dax)
{
/* all probe actions are unwound by devm */
- return 0;
}

static struct dax_device_driver device_dax_driver = {
diff --git a/drivers/dax/kmem.c b/drivers/dax/kmem.c
index 403ec42472d1..ac231cc36359 100644
--- a/drivers/dax/kmem.c
+++ b/drivers/dax/kmem.c
@@ -136,7 +136,7 @@ static int dev_dax_kmem_probe(struct dev_dax *dev_dax)
}

#ifdef CONFIG_MEMORY_HOTREMOVE
-static int dev_dax_kmem_remove(struct dev_dax *dev_dax)
+static void dev_dax_kmem_remove(struct dev_dax *dev_dax)
{
int i, success = 0;
struct device *dev = &dev_dax->dev;
@@ -176,11 +176,9 @@ static int dev_dax_kmem_remove(struct dev_dax *dev_dax)
kfree(data);
dev_set_drvdata(dev, NULL);
}
-
- return 0;
}
#else
-static int dev_dax_kmem_remove(struct dev_dax *dev_dax)
+static void dev_dax_kmem_remove(struct dev_dax *dev_dax)
{
/*
* Without hotremove purposely leak the request_mem_region() for the
@@ -190,7 +188,6 @@ static int dev_dax_kmem_remove(struct dev_dax *dev_dax)
* request_mem_region().
*/
any_hotremove_failed = true;
- return 0;
}
#endif /* CONFIG_MEMORY_HOTREMOVE */

--
2.29.2