Re: [PATCH 11/16] powerpc: vio_cmo: use dev_groups and not dev_attrs for bus_type

Greg Kroah-Hartman [off-list ref] writes:

On Fri, Jun 09, 2017 at 08:53:22AM +1000, Michael Ellerman wrote:

quoted

Greg Kroah-Hartman [off-list ref] writes:

quoted

On Thu, Jun 08, 2017 at 11:12:10PM +1000, Michael Ellerman wrote:

quoted

Greg Kroah-Hartman [off-list ref] writes:

quoted

The dev_attrs field has long been "depreciated" and is finally being
removed, so move the driver to use the "correct" dev_groups field
instead for struct bus_type.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <redacted>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Vineet Gupta <redacted>
Cc: Bart Van Assche <redacted>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Joerg Roedel <redacted>
Cc: Johan Hovold <johan@kernel.org>
Cc: Alexey Kardashevskiy <redacted>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: <redacted>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/platforms/pseries/vio.c | 37 +++++++++++++++++++++---------------
 1 file changed, 22 insertions(+), 15 deletions(-)

This one needed a bit more work to get building, the incremental diff is
below. We need a forward declaration of name, devspec and modalias,
which is a bit weird, but that's how the code is currently structured.
And there's dev and bus attributes with the same name, so that needed an
added "bus".

I booted v2 of patch 10 and this one and everything looks identical to
upstream.

Ah, many thanks, this was on my todo list to fix up today.

But you renamed the sysfs files when you added "bus" to the function
names, are you sure you want to do that?  I don't mind, but if you
happen to have userspace tools that look at those files, they just broke
:(

Ugh crap, no that won't work.

I didn't see it when I tested because my machine doesn't have the CMO
feature enabled.

I guess we have to open code some of the BUS_ATTR_RO() etc. so we can
avoid the name clash.

Or split it into multiple files, I've solved this that way in the past.
You shouldn't have to "open code" BUS_ATTR_RO().

It just requires one use of __ATTR(), which seems simpler than splitting
the file in two.

Here's a new incremental diff against your patch.

I confirmed none of the cmo names changed, result after is:

./devices/vio/cmo_desired
./devices/vio/cmo_allocated
./devices/vio/cmo_entitled
./devices/vio/cmo_allocs_failed
./devices/vio/71000000/cmo_desired
./devices/vio/71000000/cmo_allocated
./devices/vio/71000000/cmo_entitled
./devices/vio/71000000/cmo_allocs_failed
./devices/vio/30000000/cmo_desired
./devices/vio/30000000/cmo_allocated
./devices/vio/30000000/cmo_entitled
./devices/vio/30000000/cmo_allocs_failed
./devices/vio/2000/cmo_desired
./devices/vio/2000/cmo_allocated
./devices/vio/2000/cmo_entitled
./devices/vio/2000/cmo_allocs_failed
./bus/vio/cmo_high
./bus/vio/cmo_spare
./bus/vio/cmo_reserve_size
./bus/vio/cmo_desired
./bus/vio/cmo_entitled
./bus/vio/cmo_excess_free
./bus/vio/cmo_excess_size
./bus/vio/cmo_min
./bus/vio/cmo_curr


cheers

diff --git a/arch/powerpc/platforms/pseries/vio.c b/arch/powerpc/platforms/pseries/vio.c
index 738196fd7e57..117beb9e8786 100644
--- a/arch/powerpc/platforms/pseries/vio.c
+++ b/arch/powerpc/platforms/pseries/vio.c

@@ -955,7 +955,7 @@ static ssize_t cmo_##name##_show(struct device *dev,                    \
 	return sprintf(buf, "%lu\n", to_vio_dev(dev)->cmo.name);        \
 }
 
-static ssize_t viodev_cmo_allocs_failed_show(struct device *dev,
+static ssize_t cmo_allocs_failed_show(struct device *dev,
 		struct device_attribute *attr, char *buf)
 {
 	struct vio_dev *viodev = to_vio_dev(dev);

@@ -993,9 +993,11 @@ static ssize_t name_show(struct device *, struct device_attribute *, char *);
 static ssize_t devspec_show(struct device *, struct device_attribute *, char *);
 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
 			     char *buf);
-static DEVICE_ATTR_RO(name);
-static DEVICE_ATTR_RO(devspec);
-static DEVICE_ATTR_RO(modalias);
+
+static struct device_attribute dev_attr_name;
+static struct device_attribute dev_attr_devspec;
+static struct device_attribute dev_attr_modalias;
+
 static DEVICE_ATTR_RO(cmo_entitled);
 static DEVICE_ATTR_RO(cmo_allocated);
 static DEVICE_ATTR_RW(cmo_desired);

@@ -1016,11 +1018,12 @@ ATTRIBUTE_GROUPS(vio_cmo_dev);
 /* sysfs bus functions and data structures for CMO */
 
 #define viobus_cmo_rd_attr(name)                                        \
-static ssize_t cmo_##name##_show(struct bus_type *bt, char *buf)        \
+static ssize_t cmo_bus_##name##_show(struct bus_type *bt, char *buf)    \
 {                                                                       \
 	return sprintf(buf, "%lu\n", vio_cmo.name);                     \
 }                                                                       \
-static BUS_ATTR_RO(cmo_##name)
+static struct bus_attribute bus_attr_cmo_bus_##name =			\
+	__ATTR(cmo_##name, S_IRUGO, cmo_bus_##name##_show, NULL)
 
 #define viobus_cmo_pool_rd_attr(name, var)                              \
 static ssize_t                                                          \

@@ -1058,11 +1061,11 @@ static ssize_t cmo_high_store(struct bus_type *bt, const char *buf,
 static BUS_ATTR_RW(cmo_high);
 
 static struct attribute *vio_bus_attrs[] = {
-	&bus_attr_cmo_entitled.attr,
-	&bus_attr_cmo_spare.attr,
-	&bus_attr_cmo_min.attr,
-	&bus_attr_cmo_desired.attr,
-	&bus_attr_cmo_curr.attr,
+	&bus_attr_cmo_bus_entitled.attr,
+	&bus_attr_cmo_bus_spare.attr,
+	&bus_attr_cmo_bus_min.attr,
+	&bus_attr_cmo_bus_desired.attr,
+	&bus_attr_cmo_bus_curr.attr,
 	&bus_attr_cmo_high.attr,
 	&bus_attr_cmo_reserve_size.attr,
 	&bus_attr_cmo_excess_size.attr,