Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759014AbcJ1H7E (ORCPT ); Fri, 28 Oct 2016 03:59:04 -0400 Received: from mail-wm0-f65.google.com ([74.125.82.65]:36331 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758919AbcJ1H7C (ORCPT ); Fri, 28 Oct 2016 03:59:02 -0400 Date: Fri, 28 Oct 2016 09:58:57 +0200 From: Daniel Vetter To: Gustavo Padovan Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Daniel Stone , Daniel Vetter , Rob Clark , Greg Hackmann , John Harrison , laurent.pinchart@ideasonboard.com, seanpaul@google.com, marcheu@google.com, m.chehab@samsung.com, Sumit Semwal , Maarten Lankhorst , Brian Starkey , Gustavo Padovan Subject: Re: [PATCH v6 6/6] drm/fence: add out-fences support Message-ID: <20161028075857.x2pczbjq5k6yehqu@phenom.ffwll.local> Mail-Followup-To: Gustavo Padovan , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Daniel Stone , Rob Clark , Greg Hackmann , John Harrison , laurent.pinchart@ideasonboard.com, seanpaul@google.com, marcheu@google.com, m.chehab@samsung.com, Sumit Semwal , Maarten Lankhorst , Brian Starkey , Gustavo Padovan References: <1477597031-5139-1-git-send-email-gustavo@padovan.org> <1477597031-5139-7-git-send-email-gustavo@padovan.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1477597031-5139-7-git-send-email-gustavo@padovan.org> X-Operating-System: Linux phenom 4.6.0-1-amd64 User-Agent: NeoMutt/20161014 (1.7.1) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 14143 Lines: 443 On Thu, Oct 27, 2016 at 05:37:11PM -0200, Gustavo Padovan wrote: > From: Gustavo Padovan > > Support DRM out-fences by creating a sync_file with a fence for each CRTC > that sets the OUT_FENCE_PTR property. > > We use the out_fence pointer received in the OUT_FENCE_PTR prop to send > the sync_file fd back to userspace. > > The sync_file and fd are allocated/created before commit, but the > fd_install operation only happens after we know that commit succeed. > > v2: Comment by Rob Clark: > - Squash commit that adds DRM_MODE_ATOMIC_OUT_FENCE flag here. > > Comment by Daniel Vetter: > - Add clean up code for out_fences > > v3: Comments by Daniel Vetter: > - create DRM_MODE_ATOMIC_EVENT_MASK > - userspace should fill out_fences_ptr with the crtc_ids for which > it wants fences back. > > v4: Create OUT_FENCE_PTR properties and remove old approach. > > v5: Comments by Brian Starkey: > - Remove extra fence_get() in atomic_ioctl() > - Check ret before iterating on the crtc_state > - check ret before fd_install > - set fence_state to NULL at the beginning > - check fence_state->out_fence_ptr before put_user() > - change order of fput() and put_unused_fd() on failure > > - Add access_ok() check to the out_fence_ptr received > - Rebase after fence -> dma_fence rename > - Store out_fence_ptr in the drm_atomic_state > - Split crtc_setup_out_fence() > - return -1 as out_fence with TEST_ONLY flag > > Signed-off-by: Gustavo Padovan I think this looks good. Again I'll wait with full in-depth review of all the input validation until the igt shows up, but I think we're mostly covereed. A few smaller comments for polish below. -Daniel > --- > drivers/gpu/drm/drm_atomic.c | 199 ++++++++++++++++++++++++++++++++++++------- > drivers/gpu/drm/drm_crtc.c | 8 ++ > include/drm/drm_atomic.h | 1 + > include/drm/drm_crtc.h | 17 ++++ > 4 files changed, 196 insertions(+), 29 deletions(-) > > diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c > index 28d9366..9b70a27 100644 > --- a/drivers/gpu/drm/drm_atomic.c > +++ b/drivers/gpu/drm/drm_atomic.c > @@ -290,6 +290,46 @@ drm_atomic_get_crtc_state(struct drm_atomic_state *state, > EXPORT_SYMBOL(drm_atomic_get_crtc_state); > > /** > + * drm_atomic_set_out_fence_for_crtc - set CRTC out fence pointer > + * @state: global atomic state object > + * @crtc: crtc to set the out fence pointer > + * @fence_ptr: the userspace pointer to user > + * > + * This function stores the out fence pointer in the atomic state. > + */ > +static void > +drm_atomic_set_out_fence_for_crtc(struct drm_atomic_state *state, > + struct drm_crtc *crtc, u64 __user *fence_ptr) > +{ > + state->crtcs[drm_crtc_index(crtc)].out_fence_ptr = fence_ptr; > +} > + > +/** > + * drm_atomic_get_out_fence_for_crtc - get CRTC out fence pointer > + * @state: global atomic state object > + * @crtc: crtc to set the out fence pointer > + * > + * Get the user pointer that should be used for to store the out fence fd. > + * This function should be called only once per atomic state as it clears > + * the out_fence_ptr store there to prevent drivers to access them. > + * > + * Returns: > + * > + * The out fence user pointer. > + */ We don't document non-driver-visble functions and structs, and especially static functions should be self explanatory. I feel bad for your effort in typing kernel-doc here :( > +static u64 __user * > +drm_atomic_get_out_fence_for_crtc(struct drm_atomic_state *state, > + struct drm_crtc *crtc) > +{ > + u64 __user *fence_ptr; > + > + fence_ptr = state->crtcs[drm_crtc_index(crtc)].out_fence_ptr; > + state->crtcs[drm_crtc_index(crtc)].out_fence_ptr = NULL; > + > + return fence_ptr; > +} > + > +/** > * drm_atomic_set_mode_for_crtc - set mode for CRTC > * @state: the CRTC whose incoming state to update > * @mode: kernel-internal mode to use for the CRTC, or NULL to disable > @@ -490,6 +530,12 @@ int drm_atomic_crtc_set_property(struct drm_crtc *crtc, > &replaced); > state->color_mgmt_changed |= replaced; > return ret; > + } else if (property == config->prop_out_fence_ptr) { > + uint64_t __user *fence_ptr = u64_to_user_ptr(val); > + if (!access_ok(VERIFY_WRITE, fence_ptr, sizeof(*fence_ptr))) > + return -EFAULT; > + > + drm_atomic_set_out_fence_for_crtc(state->state, crtc, fence_ptr); > } else if (crtc->funcs->atomic_set_property) > return crtc->funcs->atomic_set_property(crtc, state, property, val); > else > @@ -532,6 +578,8 @@ drm_atomic_crtc_get_property(struct drm_crtc *crtc, > *val = (state->ctm) ? state->ctm->base.id : 0; > else if (property == config->gamma_lut_property) > *val = (state->gamma_lut) ? state->gamma_lut->base.id : 0; > + else if (property == config->prop_out_fence_ptr) > + *val = 0; > else if (crtc->funcs->atomic_get_property) > return crtc->funcs->atomic_get_property(crtc, state, property, val); > else > @@ -1506,11 +1554,9 @@ EXPORT_SYMBOL(drm_atomic_nonblocking_commit); > */ > > static struct drm_pending_vblank_event *create_vblank_event( > - struct drm_device *dev, struct drm_file *file_priv, > - struct dma_fence *fence, uint64_t user_data) > + struct drm_device *dev, uint64_t user_data) > { > struct drm_pending_vblank_event *e = NULL; > - int ret; > > e = kzalloc(sizeof *e, GFP_KERNEL); > if (!e) > @@ -1520,17 +1566,6 @@ static struct drm_pending_vblank_event *create_vblank_event( > e->event.base.length = sizeof(e->event); > e->event.user_data = user_data; > > - if (file_priv) { > - ret = drm_event_reserve_init(dev, file_priv, &e->base, > - &e->event.base); > - if (ret) { > - kfree(e); > - return NULL; > - } > - } > - > - e->base.fence = fence; > - > return e; > } > > @@ -1635,6 +1670,38 @@ void drm_atomic_clean_old_fb(struct drm_device *dev, > } > EXPORT_SYMBOL(drm_atomic_clean_old_fb); > > +struct dma_fence *get_crtc_fence(struct drm_crtc *crtc, > + struct drm_crtc_state *crtc_state) static? > +{ > + struct dma_fence *fence; > + > + fence = kzalloc(sizeof(*fence), GFP_KERNEL); > + if (!fence) > + return NULL; > + > + dma_fence_init(fence, &drm_crtc_fence_ops, &crtc->fence_lock, > + crtc->fence_context, ++crtc->fence_seqno); > + > + return fence; > +} > + > +static int setup_out_fence(struct drm_out_fence_state *fence_state, > + struct dma_fence *fence) > +{ > + fence_state->fd = get_unused_fd_flags(O_CLOEXEC); > + if (fence_state->fd < 0) > + return fence_state->fd; > + > + if (put_user(fence_state->fd, fence_state->out_fence_ptr)) > + return -EFAULT; > + > + fence_state->sync_file = sync_file_create(fence); > + if(!fence_state->sync_file) > + return -ENOMEM; > + > + return 0; > +} > + > int drm_mode_atomic_ioctl(struct drm_device *dev, > void *data, struct drm_file *file_priv) > { > @@ -1649,9 +1716,10 @@ int drm_mode_atomic_ioctl(struct drm_device *dev, > struct drm_plane *plane; > struct drm_crtc *crtc; > struct drm_crtc_state *crtc_state; > + struct drm_out_fence_state *fence_state = NULL; > unsigned plane_mask; > int ret = 0; > - unsigned int i, j; > + unsigned int i, j, fence_idx = 0; > > /* disallow for drivers not supporting atomic: */ > if (!drm_core_check_feature(dev, DRIVER_ATOMIC)) > @@ -1766,13 +1834,33 @@ int drm_mode_atomic_ioctl(struct drm_device *dev, > drm_mode_object_unreference(obj); > } > > + fence_state = kcalloc(dev->mode_config.num_crtc, sizeof(*fence_state), > + GFP_KERNEL); > + if (!fence_state) { > + ret = -ENOMEM; > + goto out; > + } > > - if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT) { > - for_each_crtc_in_state(state, crtc, crtc_state, i) { > + for_each_crtc_in_state(state, crtc, crtc_state, i) { > + > + fence_state->out_fence_ptr = > + drm_atomic_get_out_fence_for_crtc(crtc_state->state, crtc); > + > + if (fence_state->out_fence_ptr && > + (arg->flags & DRM_MODE_ATOMIC_TEST_ONLY)) { > + if (put_user(-1, fence_state->out_fence_ptr)) { > + ret = -EFAULT; > + goto out; > + } > + > + continue; > + } > + > + if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT || > + fence_state->out_fence_ptr) { > struct drm_pending_vblank_event *e; > > - e = create_vblank_event(dev, file_priv, NULL, > - arg->user_data); > + e = create_vblank_event(dev, arg->user_data); > if (!e) { > ret = -ENOMEM; > goto out; > @@ -1780,6 +1868,39 @@ int drm_mode_atomic_ioctl(struct drm_device *dev, > > crtc_state->event = e; > } > + > + if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT) { > + struct drm_pending_vblank_event *e = crtc_state->event; > + > + if (!file_priv) > + continue; > + > + ret = drm_event_reserve_init(dev, file_priv, &e->base, > + &e->event.base); > + if (ret) { > + kfree(e); > + crtc_state->event = NULL; > + goto out; > + } > + } > + > + if (fence_state->out_fence_ptr) { > + struct dma_fence *fence; > + > + fence = get_crtc_fence(crtc, crtc_state); > + if (!fence) { > + ret = -ENOMEM; > + goto out; > + } > + > + ret = setup_out_fence(&fence_state[fence_idx++], fence); > + if (ret) { > + dma_fence_put(fence); > + goto out; > + } > + > + crtc_state->event->base.fence = fence; > + } I think the entire above loop body should be extracted into a helper function, like prepare_crtc_signalling or similar. drm_mode_atomic_ioctl is huge already as-is ;-) > } > > if (arg->flags & DRM_MODE_ATOMIC_TEST_ONLY) { > @@ -1794,24 +1915,44 @@ int drm_mode_atomic_ioctl(struct drm_device *dev, > ret = drm_atomic_commit(state); > } > > + if (ret) > + goto out; > + > + for (i = 0; i < fence_idx; i++) > + fd_install(fence_state[i].fd, fence_state[i].sync_file->file); > + > out: > drm_atomic_clean_old_fb(dev, plane_mask, ret); > > - if (ret && arg->flags & DRM_MODE_PAGE_FLIP_EVENT) { > - /* > - * TEST_ONLY and PAGE_FLIP_EVENT are mutually exclusive, > - * if they weren't, this code should be called on success > - * for TEST_ONLY too. > - */ > - > + if (ret) { > for_each_crtc_in_state(state, crtc, crtc_state, i) { > - if (!crtc_state->event) > - continue; > + /* > + * TEST_ONLY and PAGE_FLIP_EVENT are mutually > + * exclusive, if they weren't, this code should be > + * called on success for TEST_ONLY too. > + */ > + if (crtc_state->event) > + drm_event_cancel_free(dev, > + &crtc_state->event->base); > + } > > - drm_event_cancel_free(dev, &crtc_state->event->base); > + if (fence_state) { > + for (i = 0; i < fence_idx; i++) { > + if (fence_state[i].sync_file) > + fput(fence_state[i].sync_file->file); > + if (fence_state[i].fd >= 0) > + put_unused_fd(fence_state[i].fd); > + > + /* If this fails log error to the user */ > + if (fence_state[i].out_fence_ptr && > + put_user(-1, fence_state[i].out_fence_ptr)) > + DRM_INFO("Couldn't clear out_fence_ptr\n"); > + } > } Same here, for symmetry maybe a unprepare_crtc_signalling or so, to make it clear that this undoes what the first one set up. > } > > + kfree(fence_state); > + > if (ret == -EDEADLK) { > drm_atomic_state_clear(state); > drm_modeset_backoff(&ctx); > diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c > index e2a06c8..a18d81b 100644 > --- a/drivers/gpu/drm/drm_crtc.c > +++ b/drivers/gpu/drm/drm_crtc.c > @@ -274,6 +274,8 @@ int drm_crtc_init_with_planes(struct drm_device *dev, struct drm_crtc *crtc, > if (drm_core_check_feature(dev, DRIVER_ATOMIC)) { > drm_object_attach_property(&crtc->base, config->prop_active, 0); > drm_object_attach_property(&crtc->base, config->prop_mode_id, 0); > + drm_object_attach_property(&crtc->base, > + config->prop_out_fence_ptr, 0); > } > > return 0; > @@ -434,6 +436,12 @@ static int drm_mode_create_standard_properties(struct drm_device *dev) > return -ENOMEM; > dev->mode_config.prop_in_fence_fd = prop; > > + prop = drm_property_create_range(dev, DRM_MODE_PROP_ATOMIC, > + "OUT_FENCE_PTR", 0, U64_MAX); > + if (!prop) > + return -ENOMEM; > + dev->mode_config.prop_out_fence_ptr = prop; > + > prop = drm_property_create_object(dev, DRM_MODE_PROP_ATOMIC, > "CRTC_ID", DRM_MODE_OBJECT_CRTC); > if (!prop) > diff --git a/include/drm/drm_atomic.h b/include/drm/drm_atomic.h > index 2d1e9c9..ebde60e 100644 > --- a/include/drm/drm_atomic.h > +++ b/include/drm/drm_atomic.h > @@ -144,6 +144,7 @@ struct __drm_crtcs_state { > struct drm_crtc *ptr; > struct drm_crtc_state *state; > struct drm_crtc_commit *commit; > + u64 __user *out_fence_ptr; > }; > > struct __drm_connnectors_state { > diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h > index 278dbdd..2539394 100644 > --- a/include/drm/drm_crtc.h > +++ b/include/drm/drm_crtc.h > @@ -768,6 +768,18 @@ static inline struct drm_crtc *fence_to_crtc(struct dma_fence *fence) > } > > /** > + * struct drm_out_fence_state - store out_fence data for install and clean up > + * @out_fence_ptr: user pointer to store the fence fd in. > + * @sync_file: sync_file related to the out_fence > + * @fd: file descriptor to installed on the sync_file. > + */ > +struct drm_out_fence_state { > + u64 __user *out_fence_ptr; > + struct sync_file *sync_file; > + int fd; > +}; You only use this in drm_atomic.c, no need to have it in the header and document it. Please move it into drm_atomic.c, right befoer it's used. > + > +/* > * struct drm_mode_set - new values for a CRTC config change > * @fb: framebuffer to use for new config > * @crtc: CRTC whose configuration we're about to change > @@ -1245,6 +1257,11 @@ struct drm_mode_config { > */ > struct drm_property *prop_in_fence_fd; > /** > + * @prop_out_fence_ptr: Sync File fd pointer representing the > + * outgoing fences for a CRTC. > + */ > + struct drm_property *prop_out_fence_ptr; > + /** > * @prop_crtc_id: Default atomic plane property to specify the > * &drm_crtc. > */ > -- > 2.5.5 > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch