On Tue, 2022-06-07 at 01:32 +0530, Kirti Wankhede wrote: > > On 6/2/2022 10:49 PM, Eric Farman wrote: > > From: Jason Gunthorpe <jgg@xxxxxxxxxx> > > > > Many of the mdev drivers use a simple counter for keeping track of > > the > > available instances. Move this code to the core code and store the > > counter > > in the mdev_type. Implement it using correct locking, fixing mdpy. > > > > Drivers provide a get_available() callback to set the number of > > available > > instances for their mtypes which is fixed at registration time. The > > core > > provides a standard sysfs attribute to return the > > available_instances. > > > > Cc: Kirti Wankhede <kwankhede@xxxxxxxxxx> > > Cc: Jonathan Corbet <corbet@xxxxxxx> > > Cc: Tony Krowiak <akrowiak@xxxxxxxxxxxxx> > > Cc: Jason Herne <jjherne@xxxxxxxxxxxxx> > > Reviewed-by: Christoph Hellwig <hch@xxxxxx> > > Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx> > > Link: > > https://lore.kernel.org/r/7-v3-57c1502c62fd+2190-ccw_mdev_jgg@xxxxxxxxxx/ > > [farman: added Cc: tags] > > Signed-off-by: Eric Farman <farman@xxxxxxxxxxxxx> > > --- > > .../driver-api/vfio-mediated-device.rst | 4 +- > > drivers/s390/cio/vfio_ccw_drv.c | 1 - > > drivers/s390/cio/vfio_ccw_ops.c | 26 ++++--------- > > drivers/s390/cio/vfio_ccw_private.h | 2 - > > drivers/s390/crypto/vfio_ap_ops.c | 32 ++++-------- > > ---- > > drivers/s390/crypto/vfio_ap_private.h | 2 - > > drivers/vfio/mdev/mdev_core.c | 11 +++++- > > drivers/vfio/mdev/mdev_private.h | 2 + > > drivers/vfio/mdev/mdev_sysfs.c | 37 > > +++++++++++++++++++ > > include/linux/mdev.h | 2 + > > samples/vfio-mdev/mdpy.c | 22 +++-------- > > 11 files changed, 76 insertions(+), 65 deletions(-) > > > > diff --git a/Documentation/driver-api/vfio-mediated-device.rst > > b/Documentation/driver-api/vfio-mediated-device.rst > > index f410a1cd98bb..a4f7f1362fa8 100644 > > --- a/Documentation/driver-api/vfio-mediated-device.rst > > +++ b/Documentation/driver-api/vfio-mediated-device.rst > > @@ -106,6 +106,7 @@ structure to represent a mediated device's > > driver:: > > int (*probe) (struct mdev_device *dev); > > void (*remove) (struct mdev_device *dev); > > struct device_driver driver; > > + unsigned int (*get_available)(struct mdev_type *mtype); > > }; > > > > This patch conflicts with Christoph Hellwig's patch. I see > 'supported_type_groups' is not is above structure, I beleive that > your > patch is applied on top of Christoph's patch series. > > but then in below part of code, 'add_mdev_supported_type' has also > being > removed in Christoph's patch. So this patch would not get applied > cleanly. Apologies. This series was fit to 5.18 as the merge window progressed. Both this patch and the previous one have to adjust to the removal of mdev_parent_ops that came about from commit 6b42f491e17ce13f5ff7f2d1f49c73a0f4c47b20 Author: Jason Gunthorpe <jgg@xxxxxxxx> Date: Mon Apr 11 16:14:01 2022 +0200 vfio/mdev: Remove mdev_parent_ops I have this rebased for v2. Eric > > Thanks, > Kirti > > > +/* mdev_type attribute used by drivers that have an > > get_available() op */ > > +static ssize_t available_instances_show(struct mdev_type *mtype, > > + struct mdev_type_attribute > > *attr, > > + char *buf) > > +{ > > + unsigned int available; > > + > > + mutex_lock(&mdev_list_lock); > > + available = mtype->available; > > + mutex_unlock(&mdev_list_lock); > > + > > + return sysfs_emit(buf, "%u\n", available); > > +} > > +static MDEV_TYPE_ATTR_RO(available_instances); > > +static umode_t available_instances_is_visible(struct kobject > > *kobj, > > + struct attribute *attr, > > int n) > > +{ > > + struct mdev_type *type = to_mdev_type(kobj); > > + > > + if (!type->parent->ops->device_driver->get_available) > > + return 0; > > + return attr->mode; > > +} > > +static struct attribute *mdev_types_name_attrs[] = { > > + &mdev_type_attr_available_instances.attr, > > + NULL, > > +}; > > +static struct attribute_group mdev_type_available_instances_group > > = { > > + .attrs = mdev_types_name_attrs, > > + .is_visible = available_instances_is_visible, > > +}; > > + > > static const struct attribute_group *mdev_type_groups[] = { > > &mdev_type_std_group, > > + &mdev_type_available_instances_group, > > NULL, > > }; > > > > @@ -136,6 +169,10 @@ static struct mdev_type > > *add_mdev_supported_type(struct mdev_parent *parent, > > mdev_get_parent(parent); > > type->type_group_id = type_group_id; > > > > + if (parent->ops->device_driver->get_available) > > + type->available = > > + parent->ops->device_driver- > > >get_available(type); > > + > > ret = kobject_init_and_add(&type->kobj, &mdev_type_ktype, NULL, > > "%s-%s", dev_driver_string(parent- > > >dev), > > group->name); > > diff --git a/include/linux/mdev.h b/include/linux/mdev.h > > index 14655215417b..0ce1bb3dabd0 100644 > > --- a/include/linux/mdev.h > > +++ b/include/linux/mdev.h > > @@ -120,12 +120,14 @@ struct mdev_type_attribute { > > * @probe: called when new device created > > * @remove: called when device removed > > * @driver: device driver structure > > + * @get_available: Return the max number of instances that can be > > created > > * > > **/ > > struct mdev_driver { > > int (*probe)(struct mdev_device *dev); > > void (*remove)(struct mdev_device *dev); > > struct device_driver driver; > > + unsigned int (*get_available)(struct mdev_type *mtype); > > }; > >
