Dumb-buffer pitch and size is specified by width, height, bits-per-pixel plus various hardware-specific alignments. The calculation of these values is inconsistent and duplicated among drivers. The results for formats with bpp < 8 are sometimes incorrect. This series fixes this for most drivers. Default scanline pitch and buffer size are now calculated with the existing 4CC helpers. There is a new helper drm_mode_size_dumb() that calculates scanline pitch and buffer size according to driver requirements. The series fixes the common GEM implementations for DMA, SHMEM and VRAM. It further changes most implementations of dumb_create to use the new helper. A small number of drivers has more complicated calculations and will be updated by a later patches. v6: - extend TODO item (Tomi) - fix typos in documentation (Tomi) v5: - use check_mul_overflow() for overflow test (Tomi) - imx: fix intermediate code (Tomi) - rz-du: include dumb-buffers header v4: - improve UAPI documentation - document bpp special cases - use drm_warn_once() - add TODO lists - armada: fix pitch alignment v3: - document UAPI semantics - fall back to bpp-based allocation for unknown color modes - cleanups v2: - rewrite series - convert many individual drivers besides the shared GEM helpers Thomas Zimmermann (25): drm/dumb-buffers: Sanitize output on errors drm/dumb-buffers: Provide helper to set pitch and size drm/gem-dma: Compute dumb-buffer sizes with drm_mode_size_dumb() drm/gem-shmem: Compute dumb-buffer sizes with drm_mode_size_dumb() drm/gem-vram: Compute dumb-buffer sizes with drm_mode_size_dumb() drm/armada: Compute dumb-buffer sizes with drm_mode_size_dumb() drm/exynos: Compute dumb-buffer sizes with drm_mode_size_dumb() drm/gma500: Compute dumb-buffer sizes with drm_mode_size_dumb() drm/hibmc: Compute dumb-buffer sizes with drm_mode_size_dumb() drm/imx/ipuv3: Compute dumb-buffer sizes with drm_mode_size_dumb() drm/loongson: Compute dumb-buffer sizes with drm_mode_size_dumb() drm/mediatek: Compute dumb-buffer sizes with drm_mode_size_dumb() drm/msm: Compute dumb-buffer sizes with drm_mode_size_dumb() drm/nouveau: Compute dumb-buffer sizes with drm_mode_size_dumb() drm/omapdrm: Compute dumb-buffer sizes with drm_mode_size_dumb() drm/qxl: Compute dumb-buffer sizes with drm_mode_size_dumb() drm/renesas/rcar-du: Compute dumb-buffer sizes with drm_mode_size_dumb() drm/renesas/rz-du: Compute dumb-buffer sizes with drm_mode_size_dumb() drm/rockchip: Compute dumb-buffer sizes with drm_mode_size_dumb() drm/tegra: Compute dumb-buffer sizes with drm_mode_size_dumb() drm/virtio: Compute dumb-buffer sizes with drm_mode_size_dumb() drm/vmwgfx: Compute dumb-buffer sizes with drm_mode_size_dumb() drm/xe: Compute dumb-buffer sizes with drm_mode_size_dumb() drm/xen: Compute dumb-buffer sizes with drm_mode_size_dumb() drm/xlnx: Compute dumb-buffer sizes with drm_mode_size_dumb() Documentation/gpu/todo.rst | 37 ++++ drivers/gpu/drm/armada/armada_gem.c | 16 +- drivers/gpu/drm/drm_dumb_buffers.c | 170 ++++++++++++++++-- drivers/gpu/drm/drm_gem_dma_helper.c | 7 +- drivers/gpu/drm/drm_gem_shmem_helper.c | 16 +- drivers/gpu/drm/drm_gem_vram_helper.c | 89 +++------ drivers/gpu/drm/exynos/exynos_drm_gem.c | 8 +- drivers/gpu/drm/gma500/gem.c | 21 +-- .../gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c | 25 ++- drivers/gpu/drm/imx/ipuv3/imx-drm-core.c | 29 ++- drivers/gpu/drm/loongson/lsdc_gem.c | 29 +-- drivers/gpu/drm/mediatek/mtk_gem.c | 13 +- drivers/gpu/drm/msm/msm_gem.c | 27 ++- drivers/gpu/drm/nouveau/nouveau_display.c | 7 +- drivers/gpu/drm/omapdrm/omap_gem.c | 15 +- drivers/gpu/drm/qxl/qxl_dumb.c | 17 +- drivers/gpu/drm/renesas/rcar-du/rcar_du_kms.c | 7 +- drivers/gpu/drm/renesas/rz-du/rzg2l_du_kms.c | 8 +- drivers/gpu/drm/rockchip/rockchip_drm_gem.c | 12 +- drivers/gpu/drm/tegra/gem.c | 8 +- drivers/gpu/drm/virtio/virtgpu_gem.c | 11 +- drivers/gpu/drm/vmwgfx/vmwgfx_surface.c | 21 +-- drivers/gpu/drm/xe/xe_bo.c | 8 +- drivers/gpu/drm/xen/xen_drm_front.c | 7 +- drivers/gpu/drm/xlnx/zynqmp_kms.c | 7 +- include/drm/drm_dumb_buffers.h | 14 ++ include/drm/drm_gem_vram_helper.h | 6 - include/uapi/drm/drm_mode.h | 50 +++++- 28 files changed, 457 insertions(+), 228 deletions(-) create mode 100644 include/drm/drm_dumb_buffers.h -- 2.50.1