[PATCH v4 5/9] drm/client: Add client callbacks
Noralf Trønnes
noralf at tronnes.org
Tue Jul 3 13:07:50 UTC 2018
Den 03.07.2018 09.46, skrev Daniel Vetter:
> On Mon, Jul 02, 2018 at 03:54:29PM +0200, Noralf Trønnes wrote:
>> Add client callbacks and hook them up.
>> Add a list of clients per drm_device.
>>
>> Signed-off-by: Noralf Trønnes <noralf at tronnes.org>
> btw for reviewing it'd be simpler if you merge the 2 patches that add the
> client library, avoids me having to jump back&forth ..
>
> Bunch of comments below still.
> -Daniel
>
>> ---
>> drivers/gpu/drm/drm_client.c | 92 ++++++++++++++++++++++++++++++++++++-
>> drivers/gpu/drm/drm_drv.c | 7 +++
>> drivers/gpu/drm/drm_fb_cma_helper.c | 2 +-
>> drivers/gpu/drm/drm_fb_helper.c | 11 ++++-
>> drivers/gpu/drm/drm_file.c | 3 ++
>> drivers/gpu/drm/drm_probe_helper.c | 3 ++
>> include/drm/drm_client.h | 75 +++++++++++++++++++++++++++++-
>> include/drm/drm_device.h | 14 ++++++
>> 8 files changed, 201 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/drm_client.c b/drivers/gpu/drm/drm_client.c
>> index 9c9b8ac7aea3..f05ee98bd10c 100644
>> --- a/drivers/gpu/drm/drm_client.c
>> +++ b/drivers/gpu/drm/drm_client.c
>> @@ -4,6 +4,7 @@
>> */
>>
>> #include <linux/list.h>
>> +#include <linux/module.h>
>> #include <linux/mutex.h>
>> #include <linux/seq_file.h>
>> #include <linux/slab.h>
>> @@ -66,6 +67,7 @@ EXPORT_SYMBOL(drm_client_close);
>> * @dev: DRM device
>> * @client: DRM client
>> * @name: Client name
>> + * @funcs: DRM client functions (optional)
>> *
>> * Use drm_client_put() to free the client.
>> *
>> @@ -73,24 +75,47 @@ EXPORT_SYMBOL(drm_client_close);
>> * Zero on success or negative error code on failure.
>> */
>> int drm_client_new(struct drm_device *dev, struct drm_client_dev *client,
>> - const char *name)
>> + const char *name, const struct drm_client_funcs *funcs)
>> {
>> + bool registered;
>> int ret;
>>
>> if (!drm_core_check_feature(dev, DRIVER_MODESET) ||
>> !dev->driver->dumb_create || !dev->driver->gem_prime_vmap)
>> return -ENOTSUPP;
>>
>> + if (funcs && !try_module_get(funcs->owner))
>> + return -ENODEV;
>> +
>> client->dev = dev;
>> client->name = name;
>> + client->funcs = funcs;
>>
>> ret = drm_client_open(client);
>> if (ret)
>> - return ret;
>> + goto err_put_module;
>> +
>> + mutex_lock(&dev->clientlist_mutex);
>> + registered = dev->registered;
>> + if (registered)
>> + list_add(&client->list, &dev->clientlist);
>> + mutex_unlock(&dev->clientlist_mutex);
>> + if (!registered) {
>> + ret = -ENODEV;
>> + goto err_close;
>> + }
>>
>> drm_dev_get(dev);
> This only works if the caller holds a reference for us on dev already, or
> has some other guarantee that it won't disappear. Would be good to mention
> this in the kerneldoc.
>
>> return 0;
>> +
>> +err_close:
>> + drm_client_close(client);
>> +err_put_module:
>> + if (funcs)
>> + module_put(funcs->owner);
>> +
>> + return ret;
>> }
>> EXPORT_SYMBOL(drm_client_new);
>>
>> @@ -116,9 +141,72 @@ void drm_client_release(struct drm_client_dev *client)
>>
>> drm_client_close(client);
>> drm_dev_put(dev);
>> + if (client->funcs)
>> + module_put(client->funcs->owner);
>> }
>> EXPORT_SYMBOL(drm_client_release);
>>
>> +void drm_client_dev_unregister(struct drm_device *dev)
>> +{
>> + struct drm_client_dev *client, *tmp;
>> +
>> + if (!drm_core_check_feature(dev, DRIVER_MODESET))
>> + return;
>> +
>> + mutex_lock(&dev->clientlist_mutex);
>> + list_for_each_entry_safe(client, tmp, &dev->clientlist, list) {
>> + list_del(&client->list);
>> + if (client->funcs && client->funcs->unregister) {
>> + client->funcs->unregister(client);
> Hm, not ->unregister is called while holding the lock. I thought that
> blows up for you?
It is fine now that we decided that the client can't remove itself.
Only the driver can do it on drm_dev_unregister().
>> + } else {
>> + drm_client_release(client);
>> + kfree(client);
>> + }
>> + }
>> + mutex_unlock(&dev->clientlist_mutex);
>> +}
>> +
> Needs a bit of kerneldoc here since exported function. Drivers might also
> want to call this from their own hotplug handling.
drm_client_dev_hotplug() is only called by drm_kms_helper_hotplug_event().
The reason it's exported is because the helper can be built as a module.
Noralf.
>> +void drm_client_dev_hotplug(struct drm_device *dev)
>> +{
>> + struct drm_client_dev *client;
>> + int ret;
>> +
>> + if (!drm_core_check_feature(dev, DRIVER_MODESET))
>> + return;
>> +
>> + mutex_lock(&dev->clientlist_mutex);
>> + list_for_each_entry(client, &dev->clientlist, list) {
>> + if (!client->funcs || !client->funcs->hotplug)
>> + continue;
>> +
>> + ret = client->funcs->hotplug(client);
>> + DRM_DEV_DEBUG_KMS(dev->dev, "%s: ret=%d\n", client->name, ret);
>> + }
>> + mutex_unlock(&dev->clientlist_mutex);
>> +}
>> +EXPORT_SYMBOL(drm_client_dev_hotplug);
>> +
>> +void drm_client_dev_restore(struct drm_device *dev)
>> +{
>> + struct drm_client_dev *client;
>> + int ret;
>> +
>> + if (!drm_core_check_feature(dev, DRIVER_MODESET))
>> + return;
>> +
>> + mutex_lock(&dev->clientlist_mutex);
>> + list_for_each_entry(client, &dev->clientlist, list) {
>> + if (!client->funcs || !client->funcs->restore)
>> + continue;
>> +
>> + ret = client->funcs->restore(client);
>> + DRM_DEV_DEBUG_KMS(dev->dev, "%s: ret=%d\n", client->name, ret);
>> + if (!ret) /* The first one to return zero gets the privilege to restore */
>> + break;
>> + }
>> + mutex_unlock(&dev->clientlist_mutex);
>> +}
>> +
>> static void drm_client_buffer_delete(struct drm_client_buffer *buffer)
>> {
>> struct drm_device *dev = buffer->client->dev;
>> diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
>> index e7ff0b03328b..6eb935bb2f92 100644
>> --- a/drivers/gpu/drm/drm_drv.c
>> +++ b/drivers/gpu/drm/drm_drv.c
>> @@ -34,6 +34,7 @@
>> #include <linux/slab.h>
>> #include <linux/srcu.h>
>>
>> +#include <drm/drm_client.h>
>> #include <drm/drm_drv.h>
>> #include <drm/drmP.h>
>>
>> @@ -506,6 +507,7 @@ int drm_dev_init(struct drm_device *dev,
>>
>> INIT_LIST_HEAD(&dev->filelist);
>> INIT_LIST_HEAD(&dev->filelist_internal);
>> + INIT_LIST_HEAD(&dev->clientlist);
>> INIT_LIST_HEAD(&dev->ctxlist);
>> INIT_LIST_HEAD(&dev->vmalist);
>> INIT_LIST_HEAD(&dev->maplist);
>> @@ -515,6 +517,7 @@ int drm_dev_init(struct drm_device *dev,
>> spin_lock_init(&dev->event_lock);
>> mutex_init(&dev->struct_mutex);
>> mutex_init(&dev->filelist_mutex);
>> + mutex_init(&dev->clientlist_mutex);
>> mutex_init(&dev->ctxlist_mutex);
>> mutex_init(&dev->master_mutex);
>>
>> @@ -570,6 +573,7 @@ int drm_dev_init(struct drm_device *dev,
>> err_free:
>> mutex_destroy(&dev->master_mutex);
>> mutex_destroy(&dev->ctxlist_mutex);
>> + mutex_destroy(&dev->clientlist_mutex);
>> mutex_destroy(&dev->filelist_mutex);
>> mutex_destroy(&dev->struct_mutex);
>> return ret;
>> @@ -604,6 +608,7 @@ void drm_dev_fini(struct drm_device *dev)
>>
>> mutex_destroy(&dev->master_mutex);
>> mutex_destroy(&dev->ctxlist_mutex);
>> + mutex_destroy(&dev->clientlist_mutex);
>> mutex_destroy(&dev->filelist_mutex);
>> mutex_destroy(&dev->struct_mutex);
>> kfree(dev->unique);
>> @@ -859,6 +864,8 @@ void drm_dev_unregister(struct drm_device *dev)
>>
>> dev->registered = false;
>>
>> + drm_client_dev_unregister(dev);
>> +
>> if (drm_core_check_feature(dev, DRIVER_MODESET))
>> drm_modeset_unregister_all(dev);
>>
>> diff --git a/drivers/gpu/drm/drm_fb_cma_helper.c b/drivers/gpu/drm/drm_fb_cma_helper.c
>> index 5762a7c441e9..718c7f961d8a 100644
>> --- a/drivers/gpu/drm/drm_fb_cma_helper.c
>> +++ b/drivers/gpu/drm/drm_fb_cma_helper.c
>> @@ -181,7 +181,7 @@ struct drm_fbdev_cma *drm_fbdev_cma_init(struct drm_device *dev,
>>
>> fb_helper = &fbdev_cma->fb_helper;
>>
>> - ret = drm_client_new(dev, &fb_helper->client, "fbdev");
>> + ret = drm_client_new(dev, &fb_helper->client, "fbdev", NULL);
>> if (ret)
>> goto err_free;
>>
>> diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
>> index 0a0a577ebc3c..bea3a0cb324a 100644
>> --- a/drivers/gpu/drm/drm_fb_helper.c
>> +++ b/drivers/gpu/drm/drm_fb_helper.c
>> @@ -2989,8 +2989,15 @@ static void drm_fbdev_fb_destroy(struct fb_info *info)
>> }
>>
>> drm_client_framebuffer_delete(fb_helper->buffer);
>> - drm_client_release(&fb_helper->client);
>> - kfree(fb_helper);
>> + /*
>> + * FIXME:
>> + * Remove conditional when all CMA drivers have been moved over to using
>> + * drm_fbdev_generic_setup().
>> + */
>> + if (fb_helper->client.funcs) {
>> + drm_client_release(&fb_helper->client);
>> + kfree(fb_helper);
>> + }
>> }
>>
>> static int drm_fbdev_fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
>> diff --git a/drivers/gpu/drm/drm_file.c b/drivers/gpu/drm/drm_file.c
>> index 66bb403dc8ab..ffa8dc35515f 100644
>> --- a/drivers/gpu/drm/drm_file.c
>> +++ b/drivers/gpu/drm/drm_file.c
>> @@ -35,6 +35,7 @@
>> #include <linux/slab.h>
>> #include <linux/module.h>
>>
>> +#include <drm/drm_client.h>
>> #include <drm/drm_file.h>
>> #include <drm/drmP.h>
>>
>> @@ -444,6 +445,8 @@ void drm_lastclose(struct drm_device * dev)
>>
>> if (drm_core_check_feature(dev, DRIVER_LEGACY))
>> drm_legacy_dev_reinit(dev);
>> +
>> + drm_client_dev_restore(dev);
>> }
>>
>> /**
>> diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c
>> index 527743394150..26be57e28a9d 100644
>> --- a/drivers/gpu/drm/drm_probe_helper.c
>> +++ b/drivers/gpu/drm/drm_probe_helper.c
>> @@ -33,6 +33,7 @@
>> #include <linux/moduleparam.h>
>>
>> #include <drm/drmP.h>
>> +#include <drm/drm_client.h>
>> #include <drm/drm_crtc.h>
>> #include <drm/drm_fourcc.h>
>> #include <drm/drm_crtc_helper.h>
>> @@ -563,6 +564,8 @@ void drm_kms_helper_hotplug_event(struct drm_device *dev)
>> drm_sysfs_hotplug_event(dev);
>> if (dev->mode_config.funcs->output_poll_changed)
>> dev->mode_config.funcs->output_poll_changed(dev);
>> +
>> + drm_client_dev_hotplug(dev);
>> }
>> EXPORT_SYMBOL(drm_kms_helper_hotplug_event);
>>
>> diff --git a/include/drm/drm_client.h b/include/drm/drm_client.h
>> index e366f95d4414..02cbb02714d8 100644
>> --- a/include/drm/drm_client.h
>> +++ b/include/drm/drm_client.h
>> @@ -5,10 +5,66 @@
>>
>> #include <linux/types.h>
>>
>> +struct drm_client_dev;
>> struct drm_device;
>> struct drm_file;
>> struct drm_framebuffer;
>> struct drm_gem_object;
>> +struct module;
>> +
>> +/**
>> + * struct drm_client_funcs - DRM client callbacks
>> + */
>> +struct drm_client_funcs {
>> + /**
>> + * @owner: The module owner
>> + */
>> + struct module *owner;
>> +
>> + /**
>> + * @release:
>> + *
>> + * Called when the reference count is dropped to zero. Users of this
>> + * callback is responsible for calling drm_client_close() and freeing
>> + * the client structure.
>> + *
>> + * This callback is optional.
>> + */
>> + void (*release)(struct drm_client_dev *client);
> Hm, is this no longer in use?
>
>> +
>> + /**
>> + * @unregister:
>> + *
>> + * Called when &drm_device is unregistered. The client should respond by
>> + * releasing it's resources using drm_client_put(). If it can't do so
>> + * due to resoruces being tied up, like fbdev with open file handles,
>> + * it should release it's resources as soon as possible.
> This still talks about refcounting and _put ... needs a refresher.
>
>> + *
>> + * This callback is optional.
>> + */
>> + void (*unregister)(struct drm_client_dev *client);
>> +
>> + /**
>> + * @restore:
>> + *
>> + * Called on drm_lastclose(). The first client instance in the list that
>> + * returns zero gets the privilege to restore and no more clients are
>> + * called. This callback is not called after @unregister has been called.
>> + *
>> + * This callback is optional.
>> + */
>> + int (*restore)(struct drm_client_dev *client);
>> +
>> + /**
>> + * @hotplug:
>> + *
>> + * Called on drm_kms_helper_hotplug_event().
>> + * This callback is not called after @unregister has been called.
>> + *
>> + * This callback is optional.
>> + */
>> + int (*hotplug)(struct drm_client_dev *client);
>> +};
>>
>> /**
>> * struct drm_client_dev - DRM client instance
>> @@ -24,6 +80,19 @@ struct drm_client_dev {
>> */
>> const char *name;
>>
>> + /**
>> + * @list:
>> + *
>> + * List of all clients of a DRM device, linked into
>> + * &drm_device.clientlist. Protected by &drm_device.clientlist_mutex.
>> + */
>> + struct list_head list;
>> +
>> + /**
>> + * @funcs: DRM client functions (optional)
>> + */
>> + const struct drm_client_funcs *funcs;
>> +
>> /**
>> * @file: DRM file
>> */
>> @@ -31,9 +100,13 @@ struct drm_client_dev {
>> };
>>
>> int drm_client_new(struct drm_device *dev, struct drm_client_dev *client,
>> - const char *name);
>> + const char *name, const struct drm_client_funcs *funcs);
>> void drm_client_release(struct drm_client_dev *client);
>>
>> +void drm_client_dev_unregister(struct drm_device *dev);
>> +void drm_client_dev_hotplug(struct drm_device *dev);
>> +void drm_client_dev_restore(struct drm_device *dev);
>> +
>> /**
>> * struct drm_client_buffer - DRM client buffer
>> */
>> diff --git a/include/drm/drm_device.h b/include/drm/drm_device.h
>> index 9e29976d4e98..f9c6e0e3aec7 100644
>> --- a/include/drm/drm_device.h
>> +++ b/include/drm/drm_device.h
>> @@ -81,6 +81,20 @@ struct drm_device {
>> */
>> struct list_head filelist_internal;
>>
>> + /**
>> + * @clientlist_mutex:
>> + *
>> + * Protects @clientlist access.
>> + */
>> + struct mutex clientlist_mutex;
>> +
>> + /**
>> + * @clientlist:
>> + *
>> + * List of in-kernel clients. Protected by @clientlist_mutex.
>> + */
>> + struct list_head clientlist;
>> +
>> /** \name Memory management */
>> /*@{ */
>> struct list_head maplist; /**< Linked list of regions */
>> --
>> 2.15.1
>>
>> _______________________________________________
>> dri-devel mailing list
>> dri-devel at lists.freedesktop.org
>> https://lists.freedesktop.org/mailman/listinfo/dri-devel
More information about the dri-devel
mailing list