On Fri, 26 Jul 2024 14:37:53 +1000
Ben Skeggs <bskeggs@xxxxxxxxxx> wrote:
> Unify some more of the PCI/Tegra DRM driver init, both as a general
> cleanup, and because a subsequent commit changes the pointer stored
> via dev_set_drvdata(), and this allows the change to be made in one
> place.
>
> Signed-off-by: Ben Skeggs <bskeggs@xxxxxxxxxx>
> ---
> drivers/gpu/drm/nouveau/nouveau_drm.c | 93
> ++++++++++++++-------- drivers/gpu/drm/nouveau/nouveau_platform.c |
> 6 -- 2 files changed, 60 insertions(+), 39 deletions(-)
>
> diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.c
> b/drivers/gpu/drm/nouveau/nouveau_drm.c index
> eae48c87e3d5..9beff8737617 100644 ---
> a/drivers/gpu/drm/nouveau/nouveau_drm.c +++
> b/drivers/gpu/drm/nouveau/nouveau_drm.c @@ -628,20 +628,14 @@
> nouveau_drm_device_fini(struct drm_device *dev)
> destroy_workqueue(drm->sched_wq); nvif_parent_dtor(&drm->parent);
> mutex_destroy(&drm->clients_lock);
> - kfree(drm);
> }
>
> static int
> -nouveau_drm_device_init(struct drm_device *dev)
> +nouveau_drm_device_init(struct nouveau_drm *drm)
> {
> - struct nouveau_drm *drm;
> + struct drm_device *dev = drm->dev;
> int ret;
>
> - if (!(drm = kzalloc(sizeof(*drm), GFP_KERNEL)))
> - return -ENOMEM;
> - dev->dev_private = drm;
> - drm->dev = dev;
> -
> nvif_parent_ctor(&nouveau_parent, &drm->parent);
> drm->master.base.object.parent = &drm->parent;
>
> @@ -711,6 +705,12 @@ nouveau_drm_device_init(struct drm_device *dev)
> pm_runtime_put(dev->dev);
> }
>
> + ret = drm_dev_register(drm->dev, 0);
> + if (ret) {
> + nouveau_drm_device_fini(drm->dev);
> + return ret;
> + }
> +
> return 0;
> fail_dispinit:
> nouveau_display_destroy(dev);
> @@ -728,10 +728,47 @@ nouveau_drm_device_init(struct drm_device *dev)
> destroy_workqueue(drm->sched_wq);
> fail_alloc:
> nvif_parent_dtor(&drm->parent);
> - kfree(drm);
> return ret;
> }
>
> +static void
> +nouveau_drm_device_del(struct nouveau_drm *drm)
> +{
> + if (drm->dev)
> + drm_dev_put(drm->dev);
> +
Out of curiosity, Is it a valid convention in nouveau that allowing to
call the de-constructor of the *failing* object construction in the
error handling path? This usually means the de-constructor has to clean
the half-baked object silently while not be able to catch an invalid use
of the object somewhere else.
E.g. if (drm->dev)... seems more like for error handling. In a normal
tearing down path, if !drm->dev, then a WARN_ON() or OOPs is expected
to catch the case. IMO, we should not let it slip away silently.
> + kfree(drm);
> +}
> +
> +static struct nouveau_drm *
> +nouveau_drm_device_new(const struct drm_driver *drm_driver, struct
> device *parent,
> + struct nvkm_device *device)
> +{
> + struct nouveau_drm *drm;
> + int ret;
> +
> + drm = kzalloc(sizeof(*drm), GFP_KERNEL);
> + if (!drm)
> + return ERR_PTR(-ENOMEM);
> +
> + drm->dev = drm_dev_alloc(drm_driver, parent);
> + if (IS_ERR(drm->dev)) {
> + ret = PTR_ERR(drm->dev);
> + goto done;
> + }
> +
> + drm->dev->dev_private = drm;
> + dev_set_drvdata(parent, drm->dev);
> +
> +done:
> + if (ret) {
> + nouveau_drm_device_del(drm);
> + drm = NULL;
> + }
> +
> + return ret ? ERR_PTR(ret) : drm;
> +}
> +
> /*
> * On some Intel PCIe bridge controllers doing a
> * D0 -> D3hot -> D3cold -> D0 sequence causes Nvidia GPUs to not
> reappear. @@ -794,7 +831,7 @@ static int nouveau_drm_probe(struct
> pci_dev *pdev, const struct pci_device_id *pent)
> {
> struct nvkm_device *device;
> - struct drm_device *drm_dev;
> + struct nouveau_drm *drm;
> int ret;
>
> if (vga_switcheroo_client_probe_defer(pdev))
> @@ -825,9 +862,9 @@ static int nouveau_drm_probe(struct pci_dev *pdev,
> if (nouveau_atomic)
> driver_pci.driver_features |= DRIVER_ATOMIC;
>
> - drm_dev = drm_dev_alloc(&driver_pci, &pdev->dev);
> - if (IS_ERR(drm_dev)) {
> - ret = PTR_ERR(drm_dev);
> + drm = nouveau_drm_device_new(&driver_pci, &pdev->dev,
> device);
> + if (IS_ERR(drm)) {
> + ret = PTR_ERR(drm);
> goto fail_nvkm;
> }
>
> @@ -835,30 +872,22 @@ static int nouveau_drm_probe(struct pci_dev
> *pdev, if (ret)
> goto fail_drm;
>
> - pci_set_drvdata(pdev, drm_dev);
> -
> - ret = nouveau_drm_device_init(drm_dev);
> + ret = nouveau_drm_device_init(drm);
> if (ret)
> goto fail_pci;
>
> - ret = drm_dev_register(drm_dev, pent->driver_data);
> - if (ret)
> - goto fail_drm_dev_init;
> -
> - if (nouveau_drm(drm_dev)->client.device.info.ram_size <= 32
> * 1024 * 1024)
> - drm_fbdev_ttm_setup(drm_dev, 8);
> + if (drm->client.device.info.ram_size <= 32 * 1024 * 1024)
> + drm_fbdev_ttm_setup(drm->dev, 8);
> else
> - drm_fbdev_ttm_setup(drm_dev, 32);
> + drm_fbdev_ttm_setup(drm->dev, 32);
>
> quirk_broken_nv_runpm(pdev);
> return 0;
>
> -fail_drm_dev_init:
> - nouveau_drm_device_fini(drm_dev);
> fail_pci:
> pci_disable_device(pdev);
> fail_drm:
> - drm_dev_put(drm_dev);
> + nouveau_drm_device_del(drm);
> fail_nvkm:
> nvkm_device_del(&device);
> return ret;
> @@ -877,7 +906,7 @@ nouveau_drm_device_remove(struct drm_device *dev)
> device = nvkm_device_find(client->device);
>
> nouveau_drm_device_fini(dev);
> - drm_dev_put(dev);
> + nouveau_drm_device_del(drm);
> nvkm_device_del(&device);
> }
>
> @@ -1369,7 +1398,7 @@ nouveau_platform_device_create(const struct
> nvkm_device_tegra_func *func, struct platform_device *pdev,
> struct nvkm_device **pdevice)
> {
> - struct drm_device *drm;
> + struct nouveau_drm *drm;
> int err;
>
> err = nvkm_device_tegra_new(func, pdev, nouveau_config,
> nouveau_debug, @@ -1377,7 +1406,7 @@
> nouveau_platform_device_create(const struct nvkm_device_tegra_func
> *func, if (err) goto err_free;
>
> - drm = drm_dev_alloc(&driver_platform, &pdev->dev);
> + drm = nouveau_drm_device_new(&driver_platform, &pdev->dev,
> *pdevice); if (IS_ERR(drm)) {
> err = PTR_ERR(drm);
> goto err_free;
> @@ -1387,12 +1416,10 @@ nouveau_platform_device_create(const struct
> nvkm_device_tegra_func *func, if (err)
> goto err_put;
>
> - platform_set_drvdata(pdev, drm);
> -
> - return drm;
> + return drm->dev;
>
> err_put:
> - drm_dev_put(drm);
> + nouveau_drm_device_del(drm);
> err_free:
> nvkm_device_del(pdevice);
>
> diff --git a/drivers/gpu/drm/nouveau/nouveau_platform.c
> b/drivers/gpu/drm/nouveau/nouveau_platform.c index
> bf2dc7567ea4..d0a63f0f54a2 100644 ---
> a/drivers/gpu/drm/nouveau/nouveau_platform.c +++
> b/drivers/gpu/drm/nouveau/nouveau_platform.c @@ -34,12 +34,6 @@
> static int nouveau_platform_probe(struct platform_device *pdev) if
> (IS_ERR(drm)) return PTR_ERR(drm);
>
> - ret = drm_dev_register(drm, 0);
> - if (ret < 0) {
> - drm_dev_put(drm);
> - return ret;
> - }
> -
> return 0;
> }
>
