On Mon, Mar 23, 2020 at 03:49:21PM +0100, Daniel Vetter wrote:
> The cleanup here is somewhat tricky, since we can't tell apart the
> allocated minor index from 0. So register a cleanup action first, and
> if the index allocation fails, unregister that cleanup action again to
> avoid bad mistakes.
>
> The kdev for the minor already handles NULL, so no problem there.
>
> Hence add drmm_remove_action() to the drm_managed library.
>
> v2: Make pointer math around void ** consistent with what Laurent
> suggested.
>
> v3: Use drmm_add_action_or_reset and remove drmm_remove_action. Noticed
> because of some questions from Thomas. This also means we need to move
> the drmm_add_action_or_reset helper earlier in the series.
>
> Cc: Thomas Zimmermann <tzimmerm...@suse.de>
> Cc: Laurent Pinchart <laurent.pinch...@ideasonboard.com>
> Signed-off-by: Daniel Vetter <daniel.vet...@intel.com>
> ---
> drivers/gpu/drm/drm_drv.c | 70 ++++++++++++-----------------------
> drivers/gpu/drm/drm_managed.c | 14 +++++++
> include/drm/drm_managed.h | 9 ++++-
> 3 files changed, 46 insertions(+), 47 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
> index a710c53d13a8..25fc2107057c 100644
> --- a/drivers/gpu/drm/drm_drv.c
> +++ b/drivers/gpu/drm/drm_drv.c
> @@ -93,13 +93,25 @@ static struct drm_minor **drm_minor_get_slot(struct
> drm_device *dev,
> }
> }
>
> +static void drm_minor_alloc_release(struct drm_device *dev, void *data)
> +{
> + struct drm_minor *minor = data;
> + unsigned long flags;
> +
> + put_device(minor->kdev);
> +
> + spin_lock_irqsave(&drm_minor_lock, flags);
> + idr_remove(&drm_minors_idr, minor->index);
> + spin_unlock_irqrestore(&drm_minor_lock, flags);
> +}
> +
> static int drm_minor_alloc(struct drm_device *dev, unsigned int type)
> {
> struct drm_minor *minor;
> unsigned long flags;
> int r;
>
> - minor = kzalloc(sizeof(*minor), GFP_KERNEL);
> + minor = drmm_kzalloc(dev, sizeof(*minor), GFP_KERNEL);
> if (!minor)
> return -ENOMEM;
>
> @@ -117,46 +129,19 @@ static int drm_minor_alloc(struct drm_device *dev,
> unsigned int type)
> idr_preload_end();
>
> if (r < 0)
> - goto err_free;
> + return r;
>
> - minor->index = r;
> + r = drmm_add_action_or_reset(dev, drm_minor_alloc_release, minor);
> + if (r)
> + return r;
>
> + minor->index = r;
This looks wrong.
We do:
r = idr_alloc(&drm_minors_idr,
And then we loose the value when we reuse r
in the call to drmm_add_action_or_reset().
So the index we assign is the return value of
drmm_add_action_or_reset() and not the ID returned
by idr_alloc()
With this fixed:
Reviewed-by: Sam Ravnborg <s...@ravnborg.org>
> minor->kdev = drm_sysfs_minor_alloc(minor);
> - if (IS_ERR(minor->kdev)) {
> - r = PTR_ERR(minor->kdev);
> - goto err_index;
> - }
> + if (IS_ERR(minor->kdev))
> + return PTR_ERR(minor->kdev);
>
> *drm_minor_get_slot(dev, type) = minor;
> return 0;
> -
> -err_index:
> - spin_lock_irqsave(&drm_minor_lock, flags);
> - idr_remove(&drm_minors_idr, minor->index);
> - spin_unlock_irqrestore(&drm_minor_lock, flags);
> -err_free:
> - kfree(minor);
> - return r;
> -}
> -
> -static void drm_minor_free(struct drm_device *dev, unsigned int type)
> -{
> - struct drm_minor **slot, *minor;
> - unsigned long flags;
> -
> - slot = drm_minor_get_slot(dev, type);
> - minor = *slot;
> - if (!minor)
> - return;
> -
> - put_device(minor->kdev);
> -
> - spin_lock_irqsave(&drm_minor_lock, flags);
> - idr_remove(&drm_minors_idr, minor->index);
> - spin_unlock_irqrestore(&drm_minor_lock, flags);
> -
> - kfree(minor);
> - *slot = NULL;
> }
>
> static int drm_minor_register(struct drm_device *dev, unsigned int type)
> @@ -678,16 +663,16 @@ int drm_dev_init(struct drm_device *dev,
> if (drm_core_check_feature(dev, DRIVER_RENDER)) {
> ret = drm_minor_alloc(dev, DRM_MINOR_RENDER);
> if (ret)
> - goto err_minors;
> + goto err;
> }
>
> ret = drm_minor_alloc(dev, DRM_MINOR_PRIMARY);
> if (ret)
> - goto err_minors;
> + goto err;
>
> ret = drm_legacy_create_map_hash(dev);
> if (ret)
> - goto err_minors;
> + goto err;
>
> drm_legacy_ctxbitmap_init(dev);
>
> @@ -695,7 +680,7 @@ int drm_dev_init(struct drm_device *dev,
> ret = drm_gem_init(dev);
> if (ret) {
> DRM_ERROR("Cannot initialize graphics execution manager
> (GEM)\n");
> - goto err_ctxbitmap;
> + goto err;
> }
> }
>
> @@ -708,10 +693,6 @@ int drm_dev_init(struct drm_device *dev,
> err_setunique:
> if (drm_core_check_feature(dev, DRIVER_GEM))
> drm_gem_destroy(dev);
> -err_ctxbitmap:
> -err_minors:
> - drm_minor_free(dev, DRM_MINOR_PRIMARY);
> - drm_minor_free(dev, DRM_MINOR_RENDER);
> err:
> drm_managed_release(dev);
>
> @@ -776,9 +757,6 @@ void drm_dev_fini(struct drm_device *dev)
>
> if (drm_core_check_feature(dev, DRIVER_GEM))
> drm_gem_destroy(dev);
> -
> - drm_minor_free(dev, DRM_MINOR_PRIMARY);
> - drm_minor_free(dev, DRM_MINOR_RENDER);
> }
> EXPORT_SYMBOL(drm_dev_fini);
>
> diff --git a/drivers/gpu/drm/drm_managed.c b/drivers/gpu/drm/drm_managed.c
> index c633c2ef5269..8abf3a53aeb5 100644
> --- a/drivers/gpu/drm/drm_managed.c
> +++ b/drivers/gpu/drm/drm_managed.c
> @@ -149,6 +149,20 @@ int __drmm_add_action(struct drm_device *dev,
> }
> EXPORT_SYMBOL(__drmm_add_action);
>
> +int __drmm_add_action_or_reset(struct drm_device *dev,
> + drmres_release_t action,
> + void *data, const char *name)
> +{
> + int ret;
> +
> + ret = __drmm_add_action(dev, action, data, name);
> + if (ret)
> + action(dev, data);
> +
> + return ret;
> +}
> +EXPORT_SYMBOL(__drmm_add_action_or_reset);
> +
> void *drmm_kmalloc(struct drm_device *dev, size_t size, gfp_t gfp)
> {
> struct drmres *dr;
> diff --git a/include/drm/drm_managed.h b/include/drm/drm_managed.h
> index 89e6fce9f689..2d1e29a2200c 100644
> --- a/include/drm/drm_managed.h
> +++ b/include/drm/drm_managed.h
> @@ -17,7 +17,14 @@ int __must_check __drmm_add_action(struct drm_device *dev,
> drmres_release_t action,
> void *data, const char *name);
>
> -void drmm_add_final_kfree(struct drm_device *dev, void *parent);
> +#define drmm_add_action_or_reset(dev, action, data) \
> + __drmm_add_action_or_reset(dev, action, data, #action)
> +
> +int __must_check __drmm_add_action_or_reset(struct drm_device *dev,
> + drmres_release_t action,
> + void *data, const char *name);
> +
> +void drmm_add_final_kfree(struct drm_device *dev, void *container);
There is a s/parent/container/ sneaked in here???
>
> void *drmm_kmalloc(struct drm_device *dev, size_t size, gfp_t gfp) __malloc;
> static inline void *drmm_kzalloc(struct drm_device *dev, size_t size, gfp_t
> gfp)
> --
> 2.25.1
>
> _______________________________________________
> dri-devel mailing list
> dri-de...@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
