diff options
| -rw-r--r-- | Documentation/DocBook/drm.tmpl | 4 | ||||
| -rw-r--r-- | drivers/gpu/drm/drm_prime.c | 186 | ||||
| -rw-r--r-- | include/drm/drmP.h | 12 |
3 files changed, 201 insertions, 1 deletions
diff --git a/Documentation/DocBook/drm.tmpl b/Documentation/DocBook/drm.tmpl index 6c11d77..b26de52 100644 --- a/Documentation/DocBook/drm.tmpl +++ b/Documentation/DocBook/drm.tmpl @@ -743,6 +743,10 @@ char *date;</synopsis> These two operations are mandatory for GEM drivers that support DRM PRIME. </para> + <sect4> + <title>DRM PRIME Helper Functions Reference</title> +!Pdrivers/gpu/drm/drm_prime.c PRIME Helpers + </sect4> </sect3> <sect3 id="drm-gem-objects-mapping"> <title>GEM Objects Mapping</title> diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c index 7f12573..366910d 100644 --- a/drivers/gpu/drm/drm_prime.c +++ b/drivers/gpu/drm/drm_prime.c @@ -53,7 +53,8 @@ * Self-importing: if userspace is using PRIME as a replacement for flink * then it will get a fd->handle request for a GEM object that it created. * Drivers should detect this situation and return back the gem object - * from the dma-buf private. + * from the dma-buf private. Prime will do this automatically for drivers that + * use the drm_gem_prime_{import,export} helpers. */ struct drm_prime_member { @@ -62,6 +63,137 @@ struct drm_prime_member { uint32_t handle; }; +static struct sg_table *drm_gem_map_dma_buf(struct dma_buf_attachment *attach, + enum dma_data_direction dir) +{ + struct drm_gem_object *obj = attach->dmabuf->priv; + struct sg_table *sgt; + + mutex_lock(&obj->dev->struct_mutex); + + sgt = obj->dev->driver->gem_prime_get_sg_table(obj); + + if (!IS_ERR_OR_NULL(sgt)) + dma_map_sg(attach->dev, sgt->sgl, sgt->nents, dir); + + mutex_unlock(&obj->dev->struct_mutex); + return sgt; +} + +static void drm_gem_unmap_dma_buf(struct dma_buf_attachment *attach, + struct sg_table *sgt, enum dma_data_direction dir) +{ + dma_unmap_sg(attach->dev, sgt->sgl, sgt->nents, dir); + sg_free_table(sgt); + kfree(sgt); +} + +static void drm_gem_dmabuf_release(struct dma_buf *dma_buf) +{ + struct drm_gem_object *obj = dma_buf->priv; + + if (obj->export_dma_buf == dma_buf) { + /* drop the reference on the export fd holds */ + obj->export_dma_buf = NULL; + drm_gem_object_unreference_unlocked(obj); + } +} + +static void *drm_gem_dmabuf_vmap(struct dma_buf *dma_buf) +{ + struct drm_gem_object *obj = dma_buf->priv; + struct drm_device *dev = obj->dev; + + return dev->driver->gem_prime_vmap(obj); +} + +static void drm_gem_dmabuf_vunmap(struct dma_buf *dma_buf, void *vaddr) +{ + struct drm_gem_object *obj = dma_buf->priv; + struct drm_device *dev = obj->dev; + + dev->driver->gem_prime_vunmap(obj, vaddr); +} + +static void *drm_gem_dmabuf_kmap_atomic(struct dma_buf *dma_buf, + unsigned long page_num) +{ + return NULL; +} + +static void drm_gem_dmabuf_kunmap_atomic(struct dma_buf *dma_buf, + unsigned long page_num, void *addr) +{ + +} +static void *drm_gem_dmabuf_kmap(struct dma_buf *dma_buf, + unsigned long page_num) +{ + return NULL; +} + +static void drm_gem_dmabuf_kunmap(struct dma_buf *dma_buf, + unsigned long page_num, void *addr) +{ + +} + +static int drm_gem_dmabuf_mmap(struct dma_buf *dma_buf, + struct vm_area_struct *vma) +{ + return -EINVAL; +} + +static const struct dma_buf_ops drm_gem_prime_dmabuf_ops = { + .map_dma_buf = drm_gem_map_dma_buf, + .unmap_dma_buf = drm_gem_unmap_dma_buf, + .release = drm_gem_dmabuf_release, + .kmap = drm_gem_dmabuf_kmap, + .kmap_atomic = drm_gem_dmabuf_kmap_atomic, + .kunmap = drm_gem_dmabuf_kunmap, + .kunmap_atomic = drm_gem_dmabuf_kunmap_atomic, + .mmap = drm_gem_dmabuf_mmap, + .vmap = drm_gem_dmabuf_vmap, + .vunmap = drm_gem_dmabuf_vunmap, +}; + +/** + * DOC: PRIME Helpers + * + * Drivers can implement @gem_prime_export and @gem_prime_import in terms of + * simpler APIs by using the helper functions @drm_gem_prime_export and + * @drm_gem_prime_import. These functions implement dma-buf support in terms of + * five lower-level driver callbacks: + * + * Export callbacks: + * + * - @gem_prime_pin (optional): prepare a GEM object for exporting + * + * - @gem_prime_get_sg_table: provide a scatter/gather table of pinned pages + * + * - @gem_prime_vmap: vmap a buffer exported by your driver + * + * - @gem_prime_vunmap: vunmap a buffer exported by your driver + * + * Import callback: + * + * - @gem_prime_import_sg_table (import): produce a GEM object from another + * driver's scatter/gather table + */ + +struct dma_buf *drm_gem_prime_export(struct drm_device *dev, + struct drm_gem_object *obj, int flags) +{ + if (dev->driver->gem_prime_pin) { + int ret = dev->driver->gem_prime_pin(obj); + if (ret) + return ERR_PTR(ret); + } + return dma_buf_export(obj, &drm_gem_prime_dmabuf_ops, obj->size, + 0600); +} +EXPORT_SYMBOL(drm_gem_prime_export); + int drm_gem_prime_handle_to_fd(struct drm_device *dev, struct drm_file *file_priv, uint32_t handle, uint32_t flags, int *prime_fd) @@ -117,6 +249,58 @@ int drm_gem_prime_handle_to_fd(struct drm_device *dev, } EXPORT_SYMBOL(drm_gem_prime_handle_to_fd); +struct drm_gem_object *drm_gem_prime_import(struct drm_device *dev, + struct dma_buf *dma_buf) +{ + struct dma_buf_attachment *attach; + struct sg_table *sgt; + struct drm_gem_object *obj; + int ret; + + if (!dev->driver->gem_prime_import_sg_table) + return ERR_PTR(-EINVAL); + + if (dma_buf->ops == &drm_gem_prime_dmabuf_ops) { + obj = dma_buf->priv; + if (obj->dev == dev) { + /* + * Importing dmabuf exported from out own gem increases + * refcount on gem itself instead of f_count of dmabuf. + */ + drm_gem_object_reference(obj); + dma_buf_put(dma_buf); + return obj; + } + } + + attach = dma_buf_attach(dma_buf, dev->dev); + if (IS_ERR(attach)) + return ERR_PTR(PTR_ERR(attach)); + + sgt = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL); + if (IS_ERR_OR_NULL(sgt)) { + ret = PTR_ERR(sgt); + goto fail_detach; + } + + obj = dev->driver->gem_prime_import_sg_table(dev, dma_buf->size, sgt); + if (IS_ERR(obj)) { + ret = PTR_ERR(obj); + goto fail_unmap; + } + + obj->import_attach = attach; + + return obj; + +fail_unmap: + dma_buf_unmap_attachment(attach, sgt, DMA_BIDIRECTIONAL); +fail_detach: + dma_buf_detach(dma_buf, attach); + return ERR_PTR(ret); +} +EXPORT_SYMBOL(drm_gem_prime_import); + int drm_gem_prime_fd_to_handle(struct drm_device *dev, struct drm_file *file_priv, int prime_fd, uint32_t *handle) { diff --git a/include/drm/drmP.h b/include/drm/drmP.h index 3aaa50d..2d94d74 100644 --- a/include/drm/drmP.h +++ b/include/drm/drmP.h @@ -930,6 +930,14 @@ struct drm_driver { /* import dmabuf -> GEM */ struct drm_gem_object * (*gem_prime_import)(struct drm_device *dev, struct dma_buf *dma_buf); + /* low-level interface used by drm_gem_prime_{import,export} */ + int (*gem_prime_pin)(struct drm_gem_object *obj); + struct sg_table *(*gem_prime_get_sg_table)(struct drm_gem_object *obj); + struct drm_gem_object *(*gem_prime_import_sg_table)( + struct drm_device *dev, size_t size, + struct sg_table *sgt); + void *(*gem_prime_vmap)(struct drm_gem_object *obj); + void (*gem_prime_vunmap)(struct drm_gem_object *obj, void *vaddr); /* vga arb irq handler */ void (*vgaarb_irq)(struct drm_device *dev, bool state); @@ -1562,9 +1570,13 @@ extern int drm_clients_info(struct seq_file *m, void* data); extern int drm_gem_name_info(struct seq_file *m, void *data); +extern struct dma_buf *drm_gem_prime_export(struct drm_device *dev, + struct drm_gem_object *obj, int flags); extern int drm_gem_prime_handle_to_fd(struct drm_device *dev, struct drm_file *file_priv, uint32_t handle, uint32_t flags, int *prime_fd); +extern struct drm_gem_object *drm_gem_prime_import(struct drm_device *dev, + struct dma_buf *dma_buf); extern int drm_gem_prime_fd_to_handle(struct drm_device *dev, struct drm_file *file_priv, int prime_fd, uint32_t *handle); |