Re: [PATCH 1/6] Revert "drm/prime: Unexport helpers for fd/handle conversion"

[Felix Kuehling <felix.kuehling@xxxxxxx>]

On 2023-12-04 12:49, Deucher, Alexander wrote:
> [AMD Official Use Only - General]
>
> > -----Original Message-----
> > From: Kuehling, Felix <Felix.Kuehling@xxxxxxx>
> > Sent: Friday, December 1, 2023 6:40 PM
> > To: amd-gfx@xxxxxxxxxxxxxxxxxxxxx; dri-devel@xxxxxxxxxxxxxxxxxxxxx; Deucher,
> > Alexander <Alexander.Deucher@xxxxxxx>
> > Cc: Daniel Vetter <daniel@xxxxxxxx>; Koenig, Christian
> > <Christian.Koenig@xxxxxxx>; Thomas Zimmermann
> > <tzimmermann@xxxxxxx>
> > Subject: Re: [PATCH 1/6] Revert "drm/prime: Unexport helpers for fd/handle
> > conversion"
> >
> > Hi Alex,
> >
> > I'm about to push patches 1-3 to the rebased amd-staging-drm-next. It would
> > be good to get patch 1 into drm-fixes so that Linux 6.6 will be the only kernel
> > without these prime helpers. That would minimize the hassle for DKMS driver
> > installations on future distros.
> Already done:
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0514f63cfff38a0dcb7ba9c5f245827edc0c5107

Thank you, all! I also saw Sasha Levin is backporting it to 6.6.

Cheers,
  Felix


> Alex
>
> > Thanks,
> >     Felix
> >
> >
> > On 2023-12-01 18:34, Felix Kuehling wrote:
> > > This reverts commit 71a7974ac7019afeec105a54447ae1dc7216cbb3.
> > >
> > > These helper functions are needed for KFD to export and import DMABufs
> > > the right way without duplicating the tracking of DMABufs associated
> > > with GEM objects while ensuring that move notifier callbacks are
> > > working as intended.
> > >
> > > Acked-by: Christian König <christian.koenig@xxxxxxx>
> > > Acked-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
> > > Acked-by: Daniel Vetter <daniel@xxxxxxxx>
> > > Signed-off-by: Felix Kuehling <Felix.Kuehling@xxxxxxx>
> > > ---
> > >    drivers/gpu/drm/drm_prime.c | 33 ++++++++++++++++++---------------
> > >    include/drm/drm_prime.h     |  7 +++++++
> > >    2 files changed, 25 insertions(+), 15 deletions(-)
> > >
> > > diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c
> > > index 63b709a67471..834a5e28abbe 100644
> > > --- a/drivers/gpu/drm/drm_prime.c
> > > +++ b/drivers/gpu/drm/drm_prime.c
> > > @@ -278,7 +278,7 @@ void drm_gem_dmabuf_release(struct dma_buf
> > *dma_buf)
> > >    }
> > >    EXPORT_SYMBOL(drm_gem_dmabuf_release);
> > >
> > > -/*
> > > +/**
> > >     * drm_gem_prime_fd_to_handle - PRIME import function for GEM drivers
> > >     * @dev: drm_device to import into
> > >     * @file_priv: drm file-private structure @@ -292,9 +292,9 @@
> > > EXPORT_SYMBOL(drm_gem_dmabuf_release);
> > >     *
> > >     * Returns 0 on success or a negative error code on failure.
> > >     */
> > > -static int drm_gem_prime_fd_to_handle(struct drm_device *dev,
> > > -                                 struct drm_file *file_priv, int prime_fd,
> > > -                                 uint32_t *handle)
> > > +int drm_gem_prime_fd_to_handle(struct drm_device *dev,
> > > +                          struct drm_file *file_priv, int prime_fd,
> > > +                          uint32_t *handle)
> > >    {
> > >      struct dma_buf *dma_buf;
> > >      struct drm_gem_object *obj;
> > > @@ -360,6 +360,7 @@ static int drm_gem_prime_fd_to_handle(struct
> > drm_device *dev,
> > >      dma_buf_put(dma_buf);
> > >      return ret;
> > >    }
> > > +EXPORT_SYMBOL(drm_gem_prime_fd_to_handle);
> > >
> > >    int drm_prime_fd_to_handle_ioctl(struct drm_device *dev, void *data,
> > >                               struct drm_file *file_priv)
> > > @@ -408,7 +409,7 @@ static struct dma_buf
> > *export_and_register_object(struct drm_device *dev,
> > >      return dmabuf;
> > >    }
> > >
> > > -/*
> > > +/**
> > >     * drm_gem_prime_handle_to_fd - PRIME export function for GEM drivers
> > >     * @dev: dev to export the buffer from
> > >     * @file_priv: drm file-private structure @@ -421,10 +422,10 @@
> > > static struct dma_buf *export_and_register_object(struct drm_device *dev,
> > >     * The actual exporting from GEM object to a dma-buf is done through the
> > >     * &drm_gem_object_funcs.export callback.
> > >     */
> > > -static int drm_gem_prime_handle_to_fd(struct drm_device *dev,
> > > -                                 struct drm_file *file_priv, uint32_t handle,
> > > -                                 uint32_t flags,
> > > -                                 int *prime_fd)
> > > +int drm_gem_prime_handle_to_fd(struct drm_device *dev,
> > > +                          struct drm_file *file_priv, uint32_t handle,
> > > +                          uint32_t flags,
> > > +                          int *prime_fd)
> > >    {
> > >      struct drm_gem_object *obj;
> > >      int ret = 0;
> > > @@ -506,6 +507,7 @@ static int drm_gem_prime_handle_to_fd(struct
> > > drm_device *dev,
> > >
> > >      return ret;
> > >    }
> > > +EXPORT_SYMBOL(drm_gem_prime_handle_to_fd);
> > >
> > >    int drm_prime_handle_to_fd_ioctl(struct drm_device *dev, void *data,
> > >                               struct drm_file *file_priv)
> > > @@ -864,9 +866,9 @@
> > EXPORT_SYMBOL(drm_prime_get_contiguous_size);
> > >     * @obj: GEM object to export
> > >     * @flags: flags like DRM_CLOEXEC and DRM_RDWR
> > >     *
> > > - * This is the implementation of the &drm_gem_object_funcs.export
> > > functions
> > > - * for GEM drivers using the PRIME helpers. It is used as the default
> > > for
> > > - * drivers that do not set their own.
> > > + * This is the implementation of the &drm_gem_object_funcs.export
> > > + functions for GEM drivers
> > > + * using the PRIME helpers. It is used as the default in
> > > + * drm_gem_prime_handle_to_fd().
> > >     */
> > >    struct dma_buf *drm_gem_prime_export(struct drm_gem_object *obj,
> > >                                   int flags)
> > > @@ -962,9 +964,10 @@ EXPORT_SYMBOL(drm_gem_prime_import_dev);
> > >     * @dev: drm_device to import into
> > >     * @dma_buf: dma-buf object to import
> > >     *
> > > - * This is the implementation of the gem_prime_import functions for
> > > GEM
> > > - * drivers using the PRIME helpers. It is the default for drivers
> > > that do
> > > - * not set their own &drm_driver.gem_prime_import.
> > > + * This is the implementation of the gem_prime_import functions for
> > > + GEM drivers
> > > + * using the PRIME helpers. Drivers can use this as their
> > > + * &drm_driver.gem_prime_import implementation. It is used as the
> > > + default
> > > + * implementation in drm_gem_prime_fd_to_handle().
> > >     *
> > >     * Drivers must arrange to call drm_prime_gem_destroy() from their
> > >     * &drm_gem_object_funcs.free hook when using this function.
> > > diff --git a/include/drm/drm_prime.h b/include/drm/drm_prime.h index
> > > a7abf9f3e697..2a1d01e5b56b 100644
> > > --- a/include/drm/drm_prime.h
> > > +++ b/include/drm/drm_prime.h
> > > @@ -60,12 +60,19 @@ enum dma_data_direction;
> > >
> > >    struct drm_device;
> > >    struct drm_gem_object;
> > > +struct drm_file;
> > >
> > >    /* core prime functions */
> > >    struct dma_buf *drm_gem_dmabuf_export(struct drm_device *dev,
> > >                                    struct dma_buf_export_info *exp_info);
> > >    void drm_gem_dmabuf_release(struct dma_buf *dma_buf);
> > >
> > > +int drm_gem_prime_fd_to_handle(struct drm_device *dev,
> > > +                          struct drm_file *file_priv, int prime_fd, uint32_t
> > > +*handle); int drm_gem_prime_handle_to_fd(struct drm_device *dev,
> > > +                          struct drm_file *file_priv, uint32_t handle,
> > uint32_t flags,
> > > +                          int *prime_fd);
> > > +
> > >    /* helper functions for exporting */
> > >    int drm_gem_map_attach(struct dma_buf *dma_buf,
> > >                     struct dma_buf_attachment *attach);