| Message ID | 20210622165511.3169559-3-daniel.vetter@ffwll.ch (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | implicit fencing/dma-resv rules for shared buffers | expand |
On Tue, Jun 22, 2021 at 12:55 PM Daniel Vetter <daniel.vetter@ffwll.ch> wrote: > > 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. */ For consistency you may want to format this like: /** * @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. > + */ Same comment as above. > 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. */ and here. > struct list_head list_node; > + > + /** @priv: exporter specific private data for this buffer object. */ and here. > void *priv; > + > + /** > + * @resv: > + * > + * Reservation object linked to this dma-buf. > + */ > struct dma_resv *resv; > > - /* poll support */ > + /** @poll: for userspace poll support */ here. > wait_queue_head_t poll; > > + /** @cb_excl: for userspace poll support */ > + /** @cb_shared: for userspace poll support */ Here. Either way, Reviewed-by: Alex Deucher <alexander.deucher@amd.com> > 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; > -- > 2.32.0.rc2 >
Hi Daniel. On Tue, Jun 22, 2021 at 06:54:58PM +0200, Daniel Vetter wrote: > 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. This sentence > * The attachment_uid member of @sysfs_entry is protected by dma_resv lock > * and is incremented on each attach. belongs to the paragraph describing sysfs_entry and should be moved too. Or maybe reworded and then document all fields in dma_buf_sysfs_entry? With this fixed: Acked-by: Sam Ravnborg <sam@ravnborg.org>
On Tue, Jun 22, 2021 at 9:01 PM Sam Ravnborg <sam@ravnborg.org> wrote: > > Hi Daniel. > > On Tue, Jun 22, 2021 at 06:54:58PM +0200, Daniel Vetter wrote: > > 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. > > This sentence > > * The attachment_uid member of @sysfs_entry is protected by dma_resv lock > > * and is incremented on each attach. > belongs to the paragraph describing sysfs_entry and should be moved too. > Or maybe reworded and then document all fields in dma_buf_sysfs_entry? Unfortunately kerneldoc lost the ability to document embedded structs/unions. At least last time I checked, it's a bit a bikeshed. So I'd need to pull the entire struct out. I'll just move it since it's indeed misplaced. > With this fixed: > Acked-by: Sam Ravnborg <sam@ravnborg.org> Thanks for taking a look. -Daniel
Am 22.06.21 um 18:54 schrieb Daniel Vetter: > 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 Acked-by: Christian König <christian.koenig@amd.com> > --- > 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;
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;
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(-)