Also review & update everything while we're at it.
This is prep work to smash a ton of stuff into the kerneldoc for @resv.
Signed-off-by: Daniel Vetter daniel.vetter@intel.com Cc: Sumit Semwal sumit.semwal@linaro.org Cc: "Christian König" christian.koenig@amd.com Cc: Alex Deucher alexander.deucher@amd.com Cc: Daniel Vetter daniel.vetter@ffwll.ch Cc: Dave Airlie airlied@redhat.com Cc: Nirmoy Das nirmoy.das@amd.com Cc: Deepak R Varma mh12gx2825@gmail.com Cc: Chen Li chenli@uniontech.com Cc: Kevin Wang kevin1.wang@amd.com Cc: linux-media@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org --- include/linux/dma-buf.h | 107 +++++++++++++++++++++++++++++++--------- 1 file changed, 83 insertions(+), 24 deletions(-)
diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h index 92eec38a03aa..6d18b9e448b9 100644 --- a/include/linux/dma-buf.h +++ b/include/linux/dma-buf.h @@ -289,28 +289,6 @@ struct dma_buf_ops {
/** * struct dma_buf - shared buffer object - * @size: size of the buffer; invariant over the lifetime of the buffer. - * @file: file pointer used for sharing buffers across, and for refcounting. - * @attachments: list of dma_buf_attachment that denotes all devices attached, - * protected by dma_resv lock. - * @ops: dma_buf_ops associated with this buffer object. - * @lock: used internally to serialize list manipulation, attach/detach and - * vmap/unmap - * @vmapping_counter: used internally to refcnt the vmaps - * @vmap_ptr: the current vmap ptr if vmapping_counter > 0 - * @exp_name: name of the exporter; useful for debugging. - * @name: userspace-provided name; useful for accounting and debugging, - * protected by @resv. - * @name_lock: spinlock to protect name access - * @owner: pointer to exporter module; used for refcounting when exporter is a - * kernel module. - * @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 - * @poll: for userspace poll support - * @cb_excl: for userspace poll support - * @cb_shared: for userspace poll support - * @sysfs_entry: for exposing information about this buffer in sysfs. * The attachment_uid member of @sysfs_entry is protected by dma_resv lock * and is incremented on each attach. * @@ -324,24 +302,100 @@ struct dma_buf_ops { * Device DMA access is handled by the separate &struct dma_buf_attachment. */ struct dma_buf { + /** + * @size: + * + * Size of the buffer; invariant over the lifetime of the buffer. + */ size_t size; + + /** + * @file: + * + * File pointer used for sharing buffers across, and for refcounting. + * See dma_buf_get() and dma_buf_put(). + */ struct file *file; + + /** + * @attachments: + * + * List of dma_buf_attachment that denotes all devices attached, + * protected by &dma_resv lock @resv. + */ struct list_head attachments; + + /** @ops: dma_buf_ops associated with this buffer object. */ const struct dma_buf_ops *ops; + + /** + * @lock: + * + * Used internally to serialize list manipulation, attach/detach and + * vmap/unmap. Note that in many cases this is superseeded by + * dma_resv_lock() on @resv. + */ struct mutex lock; + + /** + * @vmapping_counter: + * + * Used internally to refcnt the vmaps returned by dma_buf_vmap(). + * Protected by @lock. + */ unsigned vmapping_counter; + + /** + * @vmap_ptr: + * The current vmap ptr if @vmapping_counter > 0. Protected by @lock. + */ struct dma_buf_map vmap_ptr; + + /** + * @exp_name: + * + * Name of the exporter; useful for debugging. See the + * DMA_BUF_SET_NAME IOCTL. + */ const char *exp_name; + + /** + * @name: + * + * Userspace-provided name; useful for accounting and debugging, + * protected by dma_resv_lock() on @resv and @name_lock for read access. + */ const char *name; + + /** @name_lock: Spinlock to protect name acces for read access. */ spinlock_t name_lock; + + /** + * @owner: + * + * Pointer to exporter module; used for refcounting when exporter is a + * kernel module. + */ struct module *owner; + + /** @list_node: node for dma_buf accounting and debugging. */ struct list_head list_node; + + /** @priv: exporter specific private data for this buffer object. */ void *priv; + + /** + * @resv: + * + * Reservation object linked to this dma-buf. + */ struct dma_resv *resv;
- /* poll support */ + /** @poll: for userspace poll support */ wait_queue_head_t poll;
+ /** @cb_excl: for userspace poll support */ + /** @cb_shared: for userspace poll support */ struct dma_buf_poll_cb_t { struct dma_fence_cb cb; wait_queue_head_t *poll; @@ -349,7 +403,12 @@ struct dma_buf { __poll_t active; } cb_excl, cb_shared; #ifdef CONFIG_DMABUF_SYSFS_STATS - /* for sysfs stats */ + /** + * @sysfs_entry: + * + * For exposing information about this buffer in sysfs. See also + * `DMA-BUF statistics`_ for the uapi this enables. + */ struct dma_buf_sysfs_entry { struct kobject kobj; struct dma_buf *dmabuf;