On Fri, Jul 19, 2019 at 11:21:53AM +0200, Daniel Vetter wrote: > On Wed, Jul 17, 2019 at 02:15:37PM -0700, Rob Clark wrote: > > From: Rob Clark <robdclark@xxxxxxxxxxxx> > > > > drm_cflush_pages() is no-op on arm/arm64. But instead we can use > > dma_sync API. > > > > Fixes failures w/ vgem_test. > > > > Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx> > > --- > > An alternative approach to the series[1] I sent yesterday > > > > On the plus side, it keeps the WC buffers and avoids any drm core > > changes. On the minus side, I don't think it will work (at least > > on arm64) prior to v5.0[2], so the fix can't be backported very > > far. > > Yeah seems a lot more reasonable. > > Acked-by: Daniel Vetter <daniel.vetter@xxxxxxxx> Applied to drm-misc-fixes, thanks! Sean > > > > [1] https://patchwork.freedesktop.org/series/63771/ > > [2] depends on 356da6d0cde3323236977fce54c1f9612a742036 > > > > drivers/gpu/drm/vgem/vgem_drv.c | 130 ++++++++++++++++++++------------ > > 1 file changed, 83 insertions(+), 47 deletions(-) > > > > diff --git a/drivers/gpu/drm/vgem/vgem_drv.c b/drivers/gpu/drm/vgem/vgem_drv.c > > index 76d95b5e289c..6c9b5e20b3d4 100644 > > --- a/drivers/gpu/drm/vgem/vgem_drv.c > > +++ b/drivers/gpu/drm/vgem/vgem_drv.c > > @@ -47,10 +47,16 @@ static struct vgem_device { > > struct platform_device *platform; > > } *vgem_device; > > > > +static void sync_and_unpin(struct drm_vgem_gem_object *bo); > > +static struct page **pin_and_sync(struct drm_vgem_gem_object *bo); > > + > > static void vgem_gem_free_object(struct drm_gem_object *obj) > > { > > struct drm_vgem_gem_object *vgem_obj = to_vgem_bo(obj); > > > > + if (!obj->import_attach) > > + sync_and_unpin(vgem_obj); > > + > > kvfree(vgem_obj->pages); > > mutex_destroy(&vgem_obj->pages_lock); > > > > @@ -78,40 +84,15 @@ static vm_fault_t vgem_gem_fault(struct vm_fault *vmf) > > return VM_FAULT_SIGBUS; > > > > mutex_lock(&obj->pages_lock); > > + if (!obj->pages) > > + pin_and_sync(obj); > > if (obj->pages) { > > get_page(obj->pages[page_offset]); > > vmf->page = obj->pages[page_offset]; > > ret = 0; > > } > > mutex_unlock(&obj->pages_lock); > > - if (ret) { > > - struct page *page; > > - > > - page = shmem_read_mapping_page( > > - file_inode(obj->base.filp)->i_mapping, > > - page_offset); > > - if (!IS_ERR(page)) { > > - vmf->page = page; > > - ret = 0; > > - } else switch (PTR_ERR(page)) { > > - case -ENOSPC: > > - case -ENOMEM: > > - ret = VM_FAULT_OOM; > > - break; > > - case -EBUSY: > > - ret = VM_FAULT_RETRY; > > - break; > > - case -EFAULT: > > - case -EINVAL: > > - ret = VM_FAULT_SIGBUS; > > - break; > > - default: > > - WARN_ON(PTR_ERR(page)); > > - ret = VM_FAULT_SIGBUS; > > - break; > > - } > > > > - } > > return ret; > > } > > > > @@ -277,32 +258,93 @@ static const struct file_operations vgem_driver_fops = { > > .release = drm_release, > > }; > > > > -static struct page **vgem_pin_pages(struct drm_vgem_gem_object *bo) > > +/* Called under pages_lock, except in free path (where it can't race): */ > > +static void sync_and_unpin(struct drm_vgem_gem_object *bo) > > { > > - mutex_lock(&bo->pages_lock); > > - if (bo->pages_pin_count++ == 0) { > > - struct page **pages; > > + struct drm_device *dev = bo->base.dev; > > + > > + if (bo->table) { > > + dma_sync_sg_for_cpu(dev->dev, bo->table->sgl, > > + bo->table->nents, DMA_BIDIRECTIONAL); > > + sg_free_table(bo->table); > > + kfree(bo->table); > > + bo->table = NULL; > > + } > > + > > + if (bo->pages) { > > + drm_gem_put_pages(&bo->base, bo->pages, true, true); > > + bo->pages = NULL; > > + } > > +} > > + > > +static struct page **pin_and_sync(struct drm_vgem_gem_object *bo) > > +{ > > + struct drm_device *dev = bo->base.dev; > > + int npages = bo->base.size >> PAGE_SHIFT; > > + struct page **pages; > > + struct sg_table *sgt; > > + > > + WARN_ON(!mutex_is_locked(&bo->pages_lock)); > > + > > + pages = drm_gem_get_pages(&bo->base); > > + if (IS_ERR(pages)) { > > + bo->pages_pin_count--; > > + mutex_unlock(&bo->pages_lock); > > + return pages; > > + } > > > > - pages = drm_gem_get_pages(&bo->base); > > - if (IS_ERR(pages)) { > > - bo->pages_pin_count--; > > - mutex_unlock(&bo->pages_lock); > > - return pages; > > - } > > + sgt = drm_prime_pages_to_sg(pages, npages); > > + if (IS_ERR(sgt)) { > > + dev_err(dev->dev, > > + "failed to allocate sgt: %ld\n", > > + PTR_ERR(bo->table)); > > + drm_gem_put_pages(&bo->base, pages, false, false); > > + mutex_unlock(&bo->pages_lock); > > + return ERR_CAST(bo->table); > > + } > > + > > + /* > > + * Flush the object from the CPU cache so that importers > > + * can rely on coherent indirect access via the exported > > + * dma-address. > > + */ > > + dma_sync_sg_for_device(dev->dev, sgt->sgl, > > + sgt->nents, DMA_BIDIRECTIONAL); > > + > > + bo->pages = pages; > > + bo->table = sgt; > > + > > + return pages; > > +} > > + > > +static struct page **vgem_pin_pages(struct drm_vgem_gem_object *bo) > > +{ > > + struct page **pages; > > > > - bo->pages = pages; > > + mutex_lock(&bo->pages_lock); > > + if (bo->pages_pin_count++ == 0 && !bo->pages) { > > + pages = pin_and_sync(bo); > > + } else { > > + WARN_ON(!bo->pages); > > + pages = bo->pages; > > } > > mutex_unlock(&bo->pages_lock); > > > > - return bo->pages; > > + return pages; > > } > > > > static void vgem_unpin_pages(struct drm_vgem_gem_object *bo) > > { > > + /* > > + * We shouldn't hit this for imported bo's.. in the import > > + * case we don't own the scatter-table > > + */ > > + WARN_ON(bo->base.import_attach); > > + > > mutex_lock(&bo->pages_lock); > > if (--bo->pages_pin_count == 0) { > > - drm_gem_put_pages(&bo->base, bo->pages, true, true); > > - bo->pages = NULL; > > + WARN_ON(!bo->table); > > + sync_and_unpin(bo); > > } > > mutex_unlock(&bo->pages_lock); > > } > > @@ -310,18 +352,12 @@ static void vgem_unpin_pages(struct drm_vgem_gem_object *bo) > > static int vgem_prime_pin(struct drm_gem_object *obj) > > { > > struct drm_vgem_gem_object *bo = to_vgem_bo(obj); > > - long n_pages = obj->size >> PAGE_SHIFT; > > struct page **pages; > > > > pages = vgem_pin_pages(bo); > > if (IS_ERR(pages)) > > return PTR_ERR(pages); > > > > - /* Flush the object from the CPU cache so that importers can rely > > - * on coherent indirect access via the exported dma-address. > > - */ > > - drm_clflush_pages(pages, n_pages); > > - > > return 0; > > } > > > > -- > > 2.21.0 > > > > -- > Daniel Vetter > Software Engineer, Intel Corporation > http://blog.ffwll.ch > _______________________________________________ > dri-devel mailing list > dri-devel@xxxxxxxxxxxxxxxxxxxxx > https://lists.freedesktop.org/mailman/listinfo/dri-devel -- Sean Paul, Software Engineer, Google / Chromium OS _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
