From patchwork Tue Jan 15 20:47:42 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Aaron Plattner X-Patchwork-Id: 1981341 Return-Path: X-Original-To: patchwork-dri-devel@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by patchwork1.kernel.org (Postfix) with ESMTP id 1C0DE3FC85 for ; Tue, 15 Jan 2013 20:48:59 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 2113CE60EE for ; Tue, 15 Jan 2013 12:48:59 -0800 (PST) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from hqemgate03.nvidia.com (hqemgate03.nvidia.com [216.228.121.140]) by gabe.freedesktop.org (Postfix) with ESMTP id B9F63E610D for ; Tue, 15 Jan 2013 12:47:57 -0800 (PST) Received: from hqnvupgp06.nvidia.com (Not Verified[216.228.121.13]) by hqemgate03.nvidia.com id ; Tue, 15 Jan 2013 12:52:01 -0800 Received: from hqemhub02.nvidia.com ([172.17.108.22]) by hqnvupgp06.nvidia.com (PGP Universal service); Tue, 15 Jan 2013 12:46:46 -0800 X-PGP-Universal: processed; by hqnvupgp06.nvidia.com on Tue, 15 Jan 2013 12:46:46 -0800 Received: from tenor.nvidia.com (172.20.144.16) by hqemhub02.nvidia.com (172.20.150.31) with Microsoft SMTP Server (TLS) id 8.3.279.1; Tue, 15 Jan 2013 12:47:54 -0800 From: Aaron Plattner To: Subject: [PATCH v3 1/3] drm: add prime helpers Date: Tue, 15 Jan 2013 12:47:42 -0800 Message-ID: <1358282864-2888-2-git-send-email-aplattner@nvidia.com> X-Mailer: git-send-email 1.8.1.1 In-Reply-To: <1358282864-2888-1-git-send-email-aplattner@nvidia.com> References: <1358282864-2888-1-git-send-email-aplattner@nvidia.com> X-NVConfidentiality: public MIME-Version: 1.0 Cc: Daniel Vetter X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dri-devel-bounces+patchwork-dri-devel=patchwork.kernel.org@lists.freedesktop.org Errors-To: dri-devel-bounces+patchwork-dri-devel=patchwork.kernel.org@lists.freedesktop.org Instead of reimplementing all of the dma_buf functionality in every driver, create helpers drm_prime_import and drm_prime_export that implement them in terms of new, lower-level hook functions: gem_prime_pin: callback when a buffer is created, used to pin buffers into GTT gem_prime_get_sg_table: convert a drm_gem_object to an sg_table for export gem_prime_import_sg_table: convert an sg_table into a drm_gem_object gem_prime_vmap, gem_prime_vunmap: map and unmap an object These hooks are optional; drivers can opt in by using drm_gem_prime_import and drm_gem_prime_export as the .gem_prime_import and .gem_prime_export fields of struct drm_driver. v2: - Drop .begin_cpu_access. None of the drivers this code replaces implemented it. Having it here was a leftover from when I was trying to include i915 in this rework. - Use mutex_lock instead of mutex_lock_interruptible, as these three drivers did. This patch series shouldn't change that behavior. - Rename helpers to gem_prime_get_sg_table and gem_prime_import_sg_table. Rename struct sg_table* variables to 'sgt' for clarity. - Update drm.tmpl for these new hooks. v3: - Pass the vaddr down to the driver. This lets drivers that just call vunmap on the pointer avoid having to store the pointer in their GEM private structures. - Move documentation into a /** DOC */ comment in drm_prime.c and include it in drm.tmpl with a !P line. I tried to use !F lines to include documentation of the individual functions from drmP.h, but the docproc / kernel-doc scripts barf on that file, so hopefully this is good enough for now. - apply refcount fix from commit be8a42ae60addd8b6092535c11b42d099d6470ec ("drm/prime: drop reference on imported dma-buf come from gem") Signed-off-by: Aaron Plattner Cc: Daniel Vetter Cc: David Airlie --- Documentation/DocBook/drm.tmpl | 4 + drivers/gpu/drm/drm_prime.c | 186 ++++++++++++++++++++++++++++++++++++++++- include/drm/drmP.h | 12 +++ 3 files changed, 201 insertions(+), 1 deletion(-) diff --git a/Documentation/DocBook/drm.tmpl b/Documentation/DocBook/drm.tmpl index 4ee2304..ed40576 100644 --- a/Documentation/DocBook/drm.tmpl +++ b/Documentation/DocBook/drm.tmpl @@ -743,6 +743,10 @@ char *date; These two operations are mandatory for GEM drivers that support DRM PRIME. + + DRM PRIME Helper Functions Reference +!Pdrivers/gpu/drm/drm_prime.c PRIME Helpers + GEM Objects Mapping 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 fad21c9..2d4ca6f 100644 --- a/include/drm/drmP.h +++ b/include/drm/drmP.h @@ -919,6 +919,14 @@ 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); @@ -1540,9 +1548,13 @@ 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);