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authorDaniel Vetter <daniel.vetter@ffwll.ch>2021-01-07 10:46:32 +0100
committerDaniel Vetter <daniel.vetter@ffwll.ch>2021-01-07 10:46:32 +0100
commit18589d74f45d6af7e7614b6488543d723ebf236a (patch)
treea735d6ed4ea46926766d981c3944651fb78e2dc6 /include/linux/dma-buf.h
parente71ba9452f0b5b2e8dc8aa5445198cd9214a6a62 (diff)
parentc545781e1c55ab680dcc49c37212d5327b9d6812 (diff)
Merge tag 'drm-misc-next-2020-12-17' of git://anongit.freedesktop.org/drm/drm-misc into drm-next
drm-misc-next for v5.12: UAPI Changes: - Not necessarily one, but we document that userspace needs to force probe connectors. Cross-subsystem Changes: - Require FB_ATY_CT for aty on sparc64. - video: Fix documentation, and a few compiler warnings. - Add devicetree bindings for DP connectors. - dma-buf: Update kernel-doc, and add might_lock for resv objects in begin/end_cpu_access. Core Changes: - ttm: Warn when releasing a pinned bo. - ttm: Cleanup bo size handling. - cma-helper: Remove prime infix, and implement mmap as GEM CMA functions. - Split drm_prime_sg_to_page_addr_arrays into 2 functions. - Add a new api to install irq using devm. - Update panel kerneldoc to inline style. - Add DP support to drm/bridge. - Assorted small fixes to ttm, fb-helper, scheduler. - Add atomic_commit_setup function callback. - Automatically use the atomic gamma_set, instead of forcing drivers to declare the default atomic version. - Allow using degamma for legacy gamma if gamma is not available. - Clarify that primary/cursor planes are not tied to 1 crtc (depending on possible_crtcs). - ttm: Cleanup the lru handler. Driver Changes: - Add pm support to ingenic. - Assorted small fixes in radeon, via, rockchip, omap2fb, kmb, gma500, nouveau, virtio, hisilicon, ingenic, s6e63m0 panel, ast, udlfb. - Add BOE NV110WTM-N61, ys57pss36bh5gq, Khadas TS050 panels. - Stop using pages with drm_prime_sg_to_page_addr_arrays, and switch all callers to use ttm_sg_tt_init. - Cleanup compiler and docbook warnings in a lot of fbdev devices. - Use the drmm_vram_helper in hisilicon. - Add support for BCM2711 DSI1 in vc4. - Add support for 8-bit delta RGB panels to ingenic. - Add documentation on how to test vkms. - Convert vc4 to atomic helpers. - Use degamma instead of gamma table in omap, to add support for CTM and color encoding/range properties. - Rework omap DSI code, and merge all omapdrm modules now that the last omap panel is now a drm panel. - More refactoring of omap dsi code. - Enable 10/12 bpc outputs in vc4. Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/78381a4f-45fd-aed4-174a-94ba051edd37@linux.intel.com
Diffstat (limited to 'include/linux/dma-buf.h')
-rw-r--r--include/linux/dma-buf.h39
1 files changed, 17 insertions, 22 deletions
diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h
index cf72699cb2bc..628681bf6c99 100644
--- a/include/linux/dma-buf.h
+++ b/include/linux/dma-buf.h
@@ -85,14 +85,16 @@ struct dma_buf_ops {
/**
* @pin:
*
- * This is called by dma_buf_pin and lets the exporter know that the
- * DMA-buf can't be moved any more.
+ * This is called by dma_buf_pin() and lets the exporter know that the
+ * DMA-buf can't be moved any more. The exporter should pin the buffer
+ * into system memory to make sure it is generally accessible by other
+ * devices.
*
- * This is called with the dmabuf->resv object locked and is mutual
+ * This is called with the &dmabuf.resv object locked and is mutual
* exclusive with @cache_sgt_mapping.
*
- * This callback is optional and should only be used in limited use
- * cases like scanout and not for temporary pin operations.
+ * This is called automatically for non-dynamic importers from
+ * dma_buf_attach().
*
* Returns:
*
@@ -103,7 +105,7 @@ struct dma_buf_ops {
/**
* @unpin:
*
- * This is called by dma_buf_unpin and lets the exporter know that the
+ * This is called by dma_buf_unpin() and lets the exporter know that the
* DMA-buf can be moved again.
*
* This is called with the dmabuf->resv object locked and is mutual
@@ -183,24 +185,19 @@ struct dma_buf_ops {
* @begin_cpu_access:
*
* This is called from dma_buf_begin_cpu_access() and allows the
- * exporter to ensure that the memory is actually available for cpu
- * access - the exporter might need to allocate or swap-in and pin the
- * backing storage. The exporter also needs to ensure that cpu access is
- * coherent for the access direction. The direction can be used by the
- * exporter to optimize the cache flushing, i.e. access with a different
+ * exporter to ensure that the memory is actually coherent for cpu
+ * access. The exporter also needs to ensure that cpu access is coherent
+ * for the access direction. The direction can be used by the exporter
+ * to optimize the cache flushing, i.e. access with a different
* direction (read instead of write) might return stale or even bogus
* data (e.g. when the exporter needs to copy the data to temporary
* storage).
*
- * This callback is optional.
+ * Note that this is both called through the DMA_BUF_IOCTL_SYNC IOCTL
+ * command for userspace mappings established through @mmap, and also
+ * for kernel mappings established with @vmap.
*
- * FIXME: This is both called through the DMA_BUF_IOCTL_SYNC command
- * from userspace (where storage shouldn't be pinned to avoid handing
- * de-factor mlock rights to userspace) and for the kernel-internal
- * users of the various kmap interfaces, where the backing storage must
- * be pinned to guarantee that the atomic kmap calls can succeed. Since
- * there's no in-kernel users of the kmap interfaces yet this isn't a
- * real problem.
+ * This callback is optional.
*
* Returns:
*
@@ -216,9 +213,7 @@ struct dma_buf_ops {
*
* This is called from dma_buf_end_cpu_access() when the importer is
* done accessing the CPU. The exporter can use this to flush caches and
- * unpin any resources pinned in @begin_cpu_access.
- * The result of any dma_buf kmap calls after end_cpu_access is
- * undefined.
+ * undo anything else done in @begin_cpu_access.
*
* This callback is optional.
*