>
> Am 27.09.19 um 18:31 schrieb Frediano Ziglio:
> >> The ttm_mem_io_* functions are actually internal to TTM and shouldn't be
> >> used in a driver.
> >>
> > As far as I can see by your second patch QXL is just using exported
> > (that is not internal) functions.
> > Not that the idea of making them internal is bad but this comment is
> > a wrong statement.
>
> See the history of exporting those, that was done specifically so that
> QXL can call them (commit afe6804c045fbd69a1b75c681107b5d6df9190de).
>
> But those are the internal functions which TTM uses to call into the
> driver. That a driver uses them to call into itself doesn't seem to make
> sense.
>
The commit was merged and release in Linux 3.10 6 years ago, since
then these functions have been exported. Not saying that the QXL change
was wrong and should not have been acked and merged but after 6 years
saying that these functions are internal it's not correct.
Something like
"The ttm_mem_io_* functions were intended to be internal to TTM and
shouldn't have been used in a driver. They were exported in commit
afe6804c045fbd69a1b75c681107b5d6df9190de just for QXL."
> >> Instead call the qxl_ttm_io_mem_reserve() function directly.
> >>
> > I would add that qxl_ttm_io_mem_free is empty so the removal of
> > ttm_mem_io_free is fine.
>
> Good point, going to add that.
>
> Thanks,
> Christian.
>
Frediano
> >
> >> Signed-off-by: Christian König <christian.koenig@xxxxxxx>
> >> ---
> >> drivers/gpu/drm/qxl/qxl_drv.h | 2 ++
> >> drivers/gpu/drm/qxl/qxl_object.c | 11 +----------
> >> drivers/gpu/drm/qxl/qxl_ttm.c | 4 ++--
> >> 3 files changed, 5 insertions(+), 12 deletions(-)
> >>
> >> diff --git a/drivers/gpu/drm/qxl/qxl_drv.h b/drivers/gpu/drm/qxl/qxl_drv.h
> >> index 9e034c5fa87d..8a24f8e101da 100644
> >> --- a/drivers/gpu/drm/qxl/qxl_drv.h
> >> +++ b/drivers/gpu/drm/qxl/qxl_drv.h
> >> @@ -354,6 +354,8 @@ int qxl_mode_dumb_mmap(struct drm_file *filp,
> >> /* qxl ttm */
> >> int qxl_ttm_init(struct qxl_device *qdev);
> >> void qxl_ttm_fini(struct qxl_device *qdev);
> >> +int qxl_ttm_io_mem_reserve(struct ttm_bo_device *bdev,
> >> + struct ttm_mem_reg *mem);
> >> int qxl_mmap(struct file *filp, struct vm_area_struct *vma);
> >>
> >> /* qxl image */
> >> diff --git a/drivers/gpu/drm/qxl/qxl_object.c
> >> b/drivers/gpu/drm/qxl/qxl_object.c
> >> index 548dfe6f3b26..299e63a951c5 100644
> >> --- a/drivers/gpu/drm/qxl/qxl_object.c
> >> +++ b/drivers/gpu/drm/qxl/qxl_object.c
> >> @@ -148,7 +148,6 @@ int qxl_bo_kmap(struct qxl_bo *bo, void **ptr)
> >> void *qxl_bo_kmap_atomic_page(struct qxl_device *qdev,
> >> struct qxl_bo *bo, int page_offset)
> >> {
> >> - struct ttm_mem_type_manager *man =
> >> &bo->tbo.bdev->man[bo->tbo.mem.mem_type];
> >> void *rptr;
> >> int ret;
> >> struct io_mapping *map;
> >> @@ -160,9 +159,7 @@ void *qxl_bo_kmap_atomic_page(struct qxl_device *qdev,
> >> else
> >> goto fallback;
> >>
> >> - (void) ttm_mem_io_lock(man, false);
> >> - ret = ttm_mem_io_reserve(bo->tbo.bdev, &bo->tbo.mem);
> >> - ttm_mem_io_unlock(man);
> >> + ret = qxl_ttm_io_mem_reserve(bo->tbo.bdev, &bo->tbo.mem);
> >>
> >> return io_mapping_map_atomic_wc(map, bo->tbo.mem.bus.offset +
> >> page_offset);
> >> fallback:
> >> @@ -193,17 +190,11 @@ void qxl_bo_kunmap(struct qxl_bo *bo)
> >> void qxl_bo_kunmap_atomic_page(struct qxl_device *qdev,
> >> struct qxl_bo *bo, void *pmap)
> >> {
> >> - struct ttm_mem_type_manager *man =
> >> &bo->tbo.bdev->man[bo->tbo.mem.mem_type];
> >> -
> >> if ((bo->tbo.mem.mem_type != TTM_PL_VRAM) &&
> >> (bo->tbo.mem.mem_type != TTM_PL_PRIV))
> >> goto fallback;
> >>
> >> io_mapping_unmap_atomic(pmap);
> >> -
> >> - (void) ttm_mem_io_lock(man, false);
> >> - ttm_mem_io_free(bo->tbo.bdev, &bo->tbo.mem);
> >> - ttm_mem_io_unlock(man);
> >> return;
> >> fallback:
> >> qxl_bo_kunmap(bo);
> >> diff --git a/drivers/gpu/drm/qxl/qxl_ttm.c b/drivers/gpu/drm/qxl/qxl_ttm.c
> >> index 9b24514c75aa..cb80e512dd46 100644
> >> --- a/drivers/gpu/drm/qxl/qxl_ttm.c
> >> +++ b/drivers/gpu/drm/qxl/qxl_ttm.c
> >> @@ -159,8 +159,8 @@ static int qxl_verify_access(struct ttm_buffer_object
> >> *bo, struct file *filp)
> >> filp->private_data);
> >> }
> >>
> >> -static int qxl_ttm_io_mem_reserve(struct ttm_bo_device *bdev,
> >> - struct ttm_mem_reg *mem)
> >> +int qxl_ttm_io_mem_reserve(struct ttm_bo_device *bdev,
> >> + struct ttm_mem_reg *mem)
> >> {
> >> struct ttm_mem_type_manager *man = &bdev->man[mem->mem_type];
> >> struct qxl_device *qdev = qxl_get_qdev(bdev);
> > Otherwise fine for me.
> >
> > Frediano
>
>
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