From 3eba8b484216bff76cdbe10cdd773d28cd8fcce9 Mon Sep 17 00:00:00 2001 From: Maarten Lankhorst Date: Tue, 1 Jul 2014 12:57:26 +0200 Subject: dma-buf: use reservation objects MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This allows reservation objects to be used in dma-buf. it's required for implementing polling support on the fences that belong to a dma-buf. Signed-off-by: Maarten Lankhorst Acked-by: Mauro Carvalho Chehab #drivers/media/v4l2-core/ Acked-by: Thomas Hellstrom #drivers/gpu/drm/ttm Acked-by: Sumit Semwal Acked-by: Daniel Vetter Signed-off-by: Vincent Stehlé #drivers/gpu/drm/armada/ Signed-off-by: Greg Kroah-Hartman Signed-off-by: Chanho Park Conflicts: drivers/gpu/drm/armada/armada_gem.c drivers/gpu/drm/drm_prime.c drivers/gpu/drm/exynos/exynos_drm_dmabuf.c drivers/gpu/drm/i915/i915_gem_dmabuf.c drivers/gpu/drm/nouveau/nouveau_drm.c drivers/gpu/drm/nouveau/nouveau_gem.h drivers/gpu/drm/nouveau/nouveau_prime.c drivers/gpu/drm/radeon/radeon_drv.c drivers/gpu/drm/tegra/gem.c drivers/gpu/drm/ttm/ttm_object.c drivers/staging/android/ion/ion.c Change-Id: I44fbb1f41500deaf9067eb5d7e1c6ed758231d69 --- drivers/dma-buf/dma-buf.c | 22 ++- drivers/gpu/drm/drm_prime.c | 7 +- drivers/gpu/drm/exynos/exynos_drm_dmabuf.c | 4 +- drivers/gpu/drm/ttm/ttm_object.c | 222 +++++++++++++++++++++++++ drivers/media/v4l2-core/videobuf2-dma-contig.c | 2 +- include/drm/drmP.h | 3 + include/linux/dma-buf.h | 9 +- 7 files changed, 260 insertions(+), 9 deletions(-) diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index 7b9904ee7c9..68789e1db97 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -25,10 +25,12 @@ #include #include #include +#include #include #include #include #include +#include static inline int is_dma_buf_file(struct file *); @@ -56,6 +58,9 @@ static int dma_buf_release(struct inode *inode, struct file *file) list_del(&dmabuf->list_node); mutex_unlock(&db_list.lock); + if (dmabuf->resv == (struct reservation_object *)&dmabuf[1]) + reservation_object_fini(dmabuf->resv); + kfree(dmabuf); return 0; } @@ -101,6 +106,7 @@ static inline int is_dma_buf_file(struct file *file) * @size: [in] Size of the buffer * @flags: [in] mode flags for the file. * @exp_name: [in] name of the exporting module - useful for debugging. + * @resv: [in] reservation-object, NULL to allocate default one. * * Returns, on success, a newly created dma_buf object, which wraps the * supplied private data and operations for dma_buf_ops. On either missing @@ -108,10 +114,17 @@ static inline int is_dma_buf_file(struct file *file) * */ struct dma_buf *dma_buf_export_named(void *priv, const struct dma_buf_ops *ops, - size_t size, int flags, const char *exp_name) + size_t size, int flags, const char *exp_name, + struct reservation_object *resv) { struct dma_buf *dmabuf; struct file *file; + size_t alloc_size = sizeof(struct dma_buf); + if (!resv) + alloc_size += sizeof(struct reservation_object); + else + /* prevent &dma_buf[1] == dma_buf->resv */ + alloc_size += 1; if (WARN_ON(!priv || !ops || !ops->map_dma_buf @@ -123,7 +136,7 @@ struct dma_buf *dma_buf_export_named(void *priv, const struct dma_buf_ops *ops, return ERR_PTR(-EINVAL); } - dmabuf = kzalloc(sizeof(struct dma_buf), GFP_KERNEL); + dmabuf = kzalloc(alloc_size, GFP_KERNEL); if (dmabuf == NULL) return ERR_PTR(-ENOMEM); @@ -131,6 +144,11 @@ struct dma_buf *dma_buf_export_named(void *priv, const struct dma_buf_ops *ops, dmabuf->ops = ops; dmabuf->size = size; dmabuf->exp_name = exp_name; + if (!resv) { + resv = (struct reservation_object *)&dmabuf[1]; + reservation_object_init(resv); + } + dmabuf->resv = resv; file = anon_inode_getfile("dmabuf", &dma_buf_fops, dmabuf, flags); diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c index 9ac664e6d73..3c7db7d98d6 100644 --- a/drivers/gpu/drm/drm_prime.c +++ b/drivers/gpu/drm/drm_prime.c @@ -317,8 +317,13 @@ static const struct dma_buf_ops drm_gem_prime_dmabuf_ops = { struct dma_buf *drm_gem_prime_export(struct drm_device *dev, struct drm_gem_object *obj, int flags) { + struct reservation_object *robj = NULL; + + if (dev->driver->gem_prime_res_obj) + robj = dev->driver->gem_prime_res_obj(obj); + return dma_buf_export(obj, &drm_gem_prime_dmabuf_ops, obj->size, - flags); + flags, robj); } EXPORT_SYMBOL(drm_gem_prime_export); diff --git a/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c b/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c index a77cad34f7f..4dcb1009644 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c +++ b/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c @@ -238,8 +238,8 @@ struct dma_buf *exynos_dmabuf_prime_export(struct drm_device *drm_dev, flags |= O_RDWR; - return dma_buf_export(exynos_gem_obj, &exynos_dmabuf_ops, - exynos_gem_obj->base.size, flags); + return dma_buf_export(obj, &exynos_dmabuf_ops, + exynos_gem_obj->base.size, flags, NULL); } struct drm_gem_object *exynos_dmabuf_prime_import(struct drm_device *drm_dev, diff --git a/drivers/gpu/drm/ttm/ttm_object.c b/drivers/gpu/drm/ttm/ttm_object.c index 58a5f3261c0..ddc3b33eef5 100644 --- a/drivers/gpu/drm/ttm/ttm_object.c +++ b/drivers/gpu/drm/ttm/ttm_object.c @@ -452,3 +452,225 @@ void ttm_object_device_release(struct ttm_object_device **p_tdev) kfree(tdev); } EXPORT_SYMBOL(ttm_object_device_release); + +/** + * get_dma_buf_unless_doomed - get a dma_buf reference if possible. + * + * @dma_buf: Non-refcounted pointer to a struct dma-buf. + * + * Obtain a file reference from a lookup structure that doesn't refcount + * the file, but synchronizes with its release method to make sure it has + * not been freed yet. See for example kref_get_unless_zero documentation. + * Returns true if refcounting succeeds, false otherwise. + * + * Nobody really wants this as a public API yet, so let it mature here + * for some time... + */ +static bool __must_check get_dma_buf_unless_doomed(struct dma_buf *dmabuf) +{ + return atomic_long_inc_not_zero(&dmabuf->file->f_count) != 0L; +} + +/** + * ttm_prime_refcount_release - refcount release method for a prime object. + * + * @p_base: Pointer to ttm_base_object pointer. + * + * This is a wrapper that calls the refcount_release founction of the + * underlying object. At the same time it cleans up the prime object. + * This function is called when all references to the base object we + * derive from are gone. + */ +static void ttm_prime_refcount_release(struct ttm_base_object **p_base) +{ + struct ttm_base_object *base = *p_base; + struct ttm_prime_object *prime; + + *p_base = NULL; + prime = container_of(base, struct ttm_prime_object, base); + BUG_ON(prime->dma_buf != NULL); + mutex_destroy(&prime->mutex); + if (prime->refcount_release) + prime->refcount_release(&base); +} + +/** + * ttm_prime_dmabuf_release - Release method for the dma-bufs we export + * + * @dma_buf: + * + * This function first calls the dma_buf release method the driver + * provides. Then it cleans up our dma_buf pointer used for lookup, + * and finally releases the reference the dma_buf has on our base + * object. + */ +static void ttm_prime_dmabuf_release(struct dma_buf *dma_buf) +{ + struct ttm_prime_object *prime = + (struct ttm_prime_object *) dma_buf->priv; + struct ttm_base_object *base = &prime->base; + struct ttm_object_device *tdev = base->tfile->tdev; + + if (tdev->dmabuf_release) + tdev->dmabuf_release(dma_buf); + mutex_lock(&prime->mutex); + if (prime->dma_buf == dma_buf) + prime->dma_buf = NULL; + mutex_unlock(&prime->mutex); + ttm_mem_global_free(tdev->mem_glob, tdev->dma_buf_size); + ttm_base_object_unref(&base); +} + +/** + * ttm_prime_fd_to_handle - Get a base object handle from a prime fd + * + * @tfile: A struct ttm_object_file identifying the caller. + * @fd: The prime / dmabuf fd. + * @handle: The returned handle. + * + * This function returns a handle to an object that previously exported + * a dma-buf. Note that we don't handle imports yet, because we simply + * have no consumers of that implementation. + */ +int ttm_prime_fd_to_handle(struct ttm_object_file *tfile, + int fd, u32 *handle) +{ + struct ttm_object_device *tdev = tfile->tdev; + struct dma_buf *dma_buf; + struct ttm_prime_object *prime; + struct ttm_base_object *base; + int ret; + + dma_buf = dma_buf_get(fd); + if (IS_ERR(dma_buf)) + return PTR_ERR(dma_buf); + + if (dma_buf->ops != &tdev->ops) + return -ENOSYS; + + prime = (struct ttm_prime_object *) dma_buf->priv; + base = &prime->base; + *handle = base->hash.key; + ret = ttm_ref_object_add(tfile, base, TTM_REF_USAGE, NULL); + + dma_buf_put(dma_buf); + + return ret; +} +EXPORT_SYMBOL_GPL(ttm_prime_fd_to_handle); + +/** + * ttm_prime_handle_to_fd - Return a dma_buf fd from a ttm prime object + * + * @tfile: Struct ttm_object_file identifying the caller. + * @handle: Handle to the object we're exporting from. + * @flags: flags for dma-buf creation. We just pass them on. + * @prime_fd: The returned file descriptor. + * + */ +int ttm_prime_handle_to_fd(struct ttm_object_file *tfile, + uint32_t handle, uint32_t flags, + int *prime_fd) +{ + struct ttm_object_device *tdev = tfile->tdev; + struct ttm_base_object *base; + struct dma_buf *dma_buf; + struct ttm_prime_object *prime; + int ret; + + base = ttm_base_object_lookup(tfile, handle); + if (unlikely(base == NULL || + base->object_type != ttm_prime_type)) { + ret = -ENOENT; + goto out_unref; + } + + prime = container_of(base, struct ttm_prime_object, base); + if (unlikely(!base->shareable)) { + ret = -EPERM; + goto out_unref; + } + + ret = mutex_lock_interruptible(&prime->mutex); + if (unlikely(ret != 0)) { + ret = -ERESTARTSYS; + goto out_unref; + } + + dma_buf = prime->dma_buf; + if (!dma_buf || !get_dma_buf_unless_doomed(dma_buf)) { + + /* + * Need to create a new dma_buf, with memory accounting. + */ + ret = ttm_mem_global_alloc(tdev->mem_glob, tdev->dma_buf_size, + false, true); + if (unlikely(ret != 0)) { + mutex_unlock(&prime->mutex); + goto out_unref; + } + + dma_buf = dma_buf_export(prime, &tdev->ops, + prime->size, flags, NULL); + if (IS_ERR(dma_buf)) { + ret = PTR_ERR(dma_buf); + ttm_mem_global_free(tdev->mem_glob, + tdev->dma_buf_size); + mutex_unlock(&prime->mutex); + goto out_unref; + } + + /* + * dma_buf has taken the base object reference + */ + base = NULL; + prime->dma_buf = dma_buf; + } + mutex_unlock(&prime->mutex); + + ret = dma_buf_fd(dma_buf, flags); + if (ret >= 0) { + *prime_fd = ret; + ret = 0; + } else + dma_buf_put(dma_buf); + +out_unref: + if (base) + ttm_base_object_unref(&base); + return ret; +} +EXPORT_SYMBOL_GPL(ttm_prime_handle_to_fd); + +/** + * ttm_prime_object_init - Initialize a ttm_prime_object + * + * @tfile: struct ttm_object_file identifying the caller + * @size: The size of the dma_bufs we export. + * @prime: The object to be initialized. + * @shareable: See ttm_base_object_init + * @type: See ttm_base_object_init + * @refcount_release: See ttm_base_object_init + * @ref_obj_release: See ttm_base_object_init + * + * Initializes an object which is compatible with the drm_prime model + * for data sharing between processes and devices. + */ +int ttm_prime_object_init(struct ttm_object_file *tfile, size_t size, + struct ttm_prime_object *prime, bool shareable, + enum ttm_object_type type, + void (*refcount_release) (struct ttm_base_object **), + void (*ref_obj_release) (struct ttm_base_object *, + enum ttm_ref_type ref_type)) +{ + mutex_init(&prime->mutex); + prime->size = PAGE_ALIGN(size); + prime->real_type = type; + prime->dma_buf = NULL; + prime->refcount_release = refcount_release; + return ttm_base_object_init(tfile, &prime->base, shareable, + ttm_prime_type, + ttm_prime_refcount_release, + ref_obj_release); +} +EXPORT_SYMBOL(ttm_prime_object_init); diff --git a/drivers/media/v4l2-core/videobuf2-dma-contig.c b/drivers/media/v4l2-core/videobuf2-dma-contig.c index 4ca73df31ba..c16f1c175f5 100644 --- a/drivers/media/v4l2-core/videobuf2-dma-contig.c +++ b/drivers/media/v4l2-core/videobuf2-dma-contig.c @@ -405,7 +405,7 @@ static struct dma_buf *vb2_dc_get_dmabuf(void *buf_priv, unsigned long flags) if (WARN_ON(!buf->sgt_base)) return NULL; - dbuf = dma_buf_export(buf, &vb2_dc_dmabuf_ops, buf->size, flags); + dbuf = dma_buf_export(buf, &vb2_dc_dmabuf_ops, buf->size, flags, NULL); if (IS_ERR(dbuf)) return NULL; diff --git a/include/drm/drmP.h b/include/drm/drmP.h index c5fae786046..cf0646da165 100644 --- a/include/drm/drmP.h +++ b/include/drm/drmP.h @@ -87,6 +87,7 @@ struct drm_device; struct device_node; struct videomode; +struct reservation_object; #include #include @@ -942,6 +943,8 @@ struct drm_driver { /* low-level interface used by drm_gem_prime_{import,export} */ int (*gem_prime_pin)(struct drm_gem_object *obj); void (*gem_prime_unpin)(struct drm_gem_object *obj); + struct reservation_object * (*gem_prime_res_obj)( + 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, diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h index f886985a28b..fd7def2e0ae 100644 --- a/include/linux/dma-buf.h +++ b/include/linux/dma-buf.h @@ -115,6 +115,7 @@ struct dma_buf_ops { * @exp_name: name of the exporter; useful for debugging. * @list_node: node for dma_buf accounting and debugging. * @priv: exporter specific private data for this buffer object. + * @resv: reservation object linked to this dma-buf */ struct dma_buf { size_t size; @@ -128,6 +129,7 @@ struct dma_buf { const char *exp_name; struct list_head list_node; void *priv; + struct reservation_object *resv; }; /** @@ -168,10 +170,11 @@ void dma_buf_detach(struct dma_buf *dmabuf, struct dma_buf_attachment *dmabuf_attach); struct dma_buf *dma_buf_export_named(void *priv, const struct dma_buf_ops *ops, - size_t size, int flags, const char *); + size_t size, int flags, const char *, + struct reservation_object *); -#define dma_buf_export(priv, ops, size, flags) \ - dma_buf_export_named(priv, ops, size, flags, KBUILD_MODNAME) +#define dma_buf_export(priv, ops, size, flags, resv) \ + dma_buf_export_named(priv, ops, size, flags, KBUILD_MODNAME, resv) int dma_buf_fd(struct dma_buf *dmabuf, int flags); struct dma_buf *dma_buf_get(int fd); -- cgit v1.2.3