From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

Make to_ext_attr() available to code that wants to reuse struct
dev_ext_attribute. While at it: make it into a static inline function.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
---
 drivers/base/core.c    | 2 --
 include/linux/device.h | 6 ++++++
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 131d96c6090b..d51e7f05d15a 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -2459,8 +2459,6 @@ static const struct sysfs_ops dev_sysfs_ops = {
 	.store	= dev_attr_store,
 };
 
-#define to_ext_attr(x) container_of(x, struct dev_ext_attribute, attr)
-
 ssize_t device_store_ulong(struct device *dev,
 			   struct device_attribute *attr,
 			   const char *buf, size_t size)
diff --git a/include/linux/device.h b/include/linux/device.h
index fc3bd7116ab9..f7957ec918a3 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -120,6 +120,12 @@ struct dev_ext_attribute {
 	void *var;
 };
 
+static inline struct dev_ext_attribute *
+to_ext_attr(struct device_attribute *attr)
+{
+	return container_of(attr, struct dev_ext_attribute, attr);
+}
+
 ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr,
 			  char *buf);
 ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr,
-- 
2.43.0

On Thu, Jun 13, 2024 at 11:28:29AM +0200, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> 
> Make to_ext_attr() available to code that wants to reuse struct
> dev_ext_attribute. While at it: make it into a static inline function.

Please don't use this, why is it needed?

thanks,

greg k-h

On Thu, Jun 13, 2024 at 12:02 PM Greg Kroah-Hartman
<gregkh@linuxfoundation.org> wrote:
>
> On Thu, Jun 13, 2024 at 11:28:29AM +0200, Bartosz Golaszewski wrote:
> > From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> >
> > Make to_ext_attr() available to code that wants to reuse struct
> > dev_ext_attribute. While at it: make it into a static inline function.
>
> Please don't use this, why is it needed?
>
> thanks,
>
> greg k-h

I had a struct in the gpio-virtuser module that consisted of a
device_attribute and a void pointer. Andy suggested reusing struct
dev_ext_attribute for that but I need this macro to access it when
only having the embedded struct device_attribute address.

Bart