| Message ID | 20200428132005.21424-11-m.szyprowski@samsung.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [RFC,01/17] drm: core: fix sg_table nents vs. orig_nents misuse | expand |
Am 28.04.20 um 15:19 schrieb Marek Szyprowski: > The Documentation/DMA-API-HOWTO.txt states that dma_map_sg returns the > numer of the created entries in the DMA address space. However the > subsequent calls to dma_sync_sg_for_{device,cpu} and dma_unmap_sg must be > called with the original number of entries passed to dma_map_sg. The > sg_table->nents in turn holds the result of the dma_map_sg call as stated > in include/linux/scatterlist.h. Adapt the code to obey those rules. > > Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Christian König <christian.koenig@amd.com> > --- > drivers/gpu/drm/radeon/radeon_ttm.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/drivers/gpu/drm/radeon/radeon_ttm.c b/drivers/gpu/drm/radeon/radeon_ttm.c > index 5d50c9e..4770880 100644 > --- a/drivers/gpu/drm/radeon/radeon_ttm.c > +++ b/drivers/gpu/drm/radeon/radeon_ttm.c > @@ -481,7 +481,7 @@ static int radeon_ttm_tt_pin_userptr(struct ttm_tt *ttm) > { > struct radeon_device *rdev = radeon_get_rdev(ttm->bdev); > struct radeon_ttm_tt *gtt = (void *)ttm; > - unsigned pinned = 0, nents; > + unsigned pinned = 0; > int r; > > int write = !(gtt->userflags & RADEON_GEM_USERPTR_READONLY); > @@ -522,8 +522,8 @@ static int radeon_ttm_tt_pin_userptr(struct ttm_tt *ttm) > goto release_sg; > > r = -ENOMEM; > - nents = dma_map_sg(rdev->dev, ttm->sg->sgl, ttm->sg->nents, direction); > - if (nents == 0) > + ttm->sg->nents = dma_map_sg(rdev->dev, ttm->sg->sgl, > + if (ttm->sg->nents == 0) > goto release_sg; > > drm_prime_sg_to_page_addr_arrays(ttm->sg, ttm->pages, > @@ -554,9 +554,9 @@ static void radeon_ttm_tt_unpin_userptr(struct ttm_tt *ttm) > return; > > /* free the sg table and pages again */ > - dma_unmap_sg(rdev->dev, ttm->sg->sgl, ttm->sg->nents, direction); > + dma_unmap_sg(rdev->dev, ttm->sg->sgl, ttm->sg->orig_nents, direction); > > - for_each_sg_page(ttm->sg->sgl, &sg_iter, ttm->sg->nents, 0) { > + for_each_sg_page(ttm->sg->sgl, &sg_iter, ttm->sg->orig_nents, 0) { > struct page *page = sg_page_iter_page(&sg_iter); > if (!(gtt->userflags & RADEON_GEM_USERPTR_READONLY)) > set_page_dirty(page);
diff --git a/drivers/gpu/drm/radeon/radeon_ttm.c b/drivers/gpu/drm/radeon/radeon_ttm.c index 5d50c9e..4770880 100644 --- a/drivers/gpu/drm/radeon/radeon_ttm.c +++ b/drivers/gpu/drm/radeon/radeon_ttm.c @@ -481,7 +481,7 @@ static int radeon_ttm_tt_pin_userptr(struct ttm_tt *ttm) { struct radeon_device *rdev = radeon_get_rdev(ttm->bdev); struct radeon_ttm_tt *gtt = (void *)ttm; - unsigned pinned = 0, nents; + unsigned pinned = 0; int r; int write = !(gtt->userflags & RADEON_GEM_USERPTR_READONLY); @@ -522,8 +522,8 @@ static int radeon_ttm_tt_pin_userptr(struct ttm_tt *ttm) goto release_sg; r = -ENOMEM; - nents = dma_map_sg(rdev->dev, ttm->sg->sgl, ttm->sg->nents, direction); - if (nents == 0) + ttm->sg->nents = dma_map_sg(rdev->dev, ttm->sg->sgl, + if (ttm->sg->nents == 0) goto release_sg; drm_prime_sg_to_page_addr_arrays(ttm->sg, ttm->pages, @@ -554,9 +554,9 @@ static void radeon_ttm_tt_unpin_userptr(struct ttm_tt *ttm) return; /* free the sg table and pages again */ - dma_unmap_sg(rdev->dev, ttm->sg->sgl, ttm->sg->nents, direction); + dma_unmap_sg(rdev->dev, ttm->sg->sgl, ttm->sg->orig_nents, direction); - for_each_sg_page(ttm->sg->sgl, &sg_iter, ttm->sg->nents, 0) { + for_each_sg_page(ttm->sg->sgl, &sg_iter, ttm->sg->orig_nents, 0) { struct page *page = sg_page_iter_page(&sg_iter); if (!(gtt->userflags & RADEON_GEM_USERPTR_READONLY)) set_page_dirty(page);
The Documentation/DMA-API-HOWTO.txt states that dma_map_sg returns the numer of the created entries in the DMA address space. However the subsequent calls to dma_sync_sg_for_{device,cpu} and dma_unmap_sg must be called with the original number of entries passed to dma_map_sg. The sg_table->nents in turn holds the result of the dma_map_sg call as stated in include/linux/scatterlist.h. Adapt the code to obey those rules. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> --- drivers/gpu/drm/radeon/radeon_ttm.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)