cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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drm_damage_helper.c (10178B)


      1// SPDX-License-Identifier: GPL-2.0 OR MIT
      2/**************************************************************************
      3 *
      4 * Copyright (c) 2018 VMware, Inc., Palo Alto, CA., USA
      5 * All Rights Reserved.
      6 *
      7 * Permission is hereby granted, free of charge, to any person obtaining a
      8 * copy of this software and associated documentation files (the
      9 * "Software"), to deal in the Software without restriction, including
     10 * without limitation the rights to use, copy, modify, merge, publish,
     11 * distribute, sub license, and/or sell copies of the Software, and to
     12 * permit persons to whom the Software is furnished to do so, subject to
     13 * the following conditions:
     14 *
     15 * The above copyright notice and this permission notice (including the
     16 * next paragraph) shall be included in all copies or substantial portions
     17 * of the Software.
     18 *
     19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
     20 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
     21 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
     22 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
     23 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
     24 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
     25 * USE OR OTHER DEALINGS IN THE SOFTWARE.
     26 *
     27 * Authors:
     28 * Deepak Rawat <drawat@vmware.com>
     29 * Rob Clark <robdclark@gmail.com>
     30 *
     31 **************************************************************************/
     32
     33#include <drm/drm_atomic.h>
     34#include <drm/drm_damage_helper.h>
     35#include <drm/drm_device.h>
     36
     37static void convert_clip_rect_to_rect(const struct drm_clip_rect *src,
     38				      struct drm_mode_rect *dest,
     39				      uint32_t num_clips, uint32_t src_inc)
     40{
     41	while (num_clips > 0) {
     42		dest->x1 = src->x1;
     43		dest->y1 = src->y1;
     44		dest->x2 = src->x2;
     45		dest->y2 = src->y2;
     46		src += src_inc;
     47		dest++;
     48		num_clips--;
     49	}
     50}
     51
     52/**
     53 * drm_atomic_helper_check_plane_damage - Verify plane damage on atomic_check.
     54 * @state: The driver state object.
     55 * @plane_state: Plane state for which to verify damage.
     56 *
     57 * This helper function makes sure that damage from plane state is discarded
     58 * for full modeset. If there are more reasons a driver would want to do a full
     59 * plane update rather than processing individual damage regions, then those
     60 * cases should be taken care of here.
     61 *
     62 * Note that &drm_plane_state.fb_damage_clips == NULL in plane state means that
     63 * full plane update should happen. It also ensure helper iterator will return
     64 * &drm_plane_state.src as damage.
     65 */
     66void drm_atomic_helper_check_plane_damage(struct drm_atomic_state *state,
     67					  struct drm_plane_state *plane_state)
     68{
     69	struct drm_crtc_state *crtc_state;
     70
     71	if (plane_state->crtc) {
     72		crtc_state = drm_atomic_get_new_crtc_state(state,
     73							   plane_state->crtc);
     74
     75		if (WARN_ON(!crtc_state))
     76			return;
     77
     78		if (drm_atomic_crtc_needs_modeset(crtc_state)) {
     79			drm_property_blob_put(plane_state->fb_damage_clips);
     80			plane_state->fb_damage_clips = NULL;
     81		}
     82	}
     83}
     84EXPORT_SYMBOL(drm_atomic_helper_check_plane_damage);
     85
     86/**
     87 * drm_atomic_helper_dirtyfb - Helper for dirtyfb.
     88 * @fb: DRM framebuffer.
     89 * @file_priv: Drm file for the ioctl call.
     90 * @flags: Dirty fb annotate flags.
     91 * @color: Color for annotate fill.
     92 * @clips: Dirty region.
     93 * @num_clips: Count of clip in clips.
     94 *
     95 * A helper to implement &drm_framebuffer_funcs.dirty using damage interface
     96 * during plane update. If num_clips is 0 then this helper will do a full plane
     97 * update. This is the same behaviour expected by DIRTFB IOCTL.
     98 *
     99 * Note that this helper is blocking implementation. This is what current
    100 * drivers and userspace expect in their DIRTYFB IOCTL implementation, as a way
    101 * to rate-limit userspace and make sure its rendering doesn't get ahead of
    102 * uploading new data too much.
    103 *
    104 * Return: Zero on success, negative errno on failure.
    105 */
    106int drm_atomic_helper_dirtyfb(struct drm_framebuffer *fb,
    107			      struct drm_file *file_priv, unsigned int flags,
    108			      unsigned int color, struct drm_clip_rect *clips,
    109			      unsigned int num_clips)
    110{
    111	struct drm_modeset_acquire_ctx ctx;
    112	struct drm_property_blob *damage = NULL;
    113	struct drm_mode_rect *rects = NULL;
    114	struct drm_atomic_state *state;
    115	struct drm_plane *plane;
    116	int ret = 0;
    117
    118	/*
    119	 * When called from ioctl, we are interruptible, but not when called
    120	 * internally (ie. defio worker)
    121	 */
    122	drm_modeset_acquire_init(&ctx,
    123		file_priv ? DRM_MODESET_ACQUIRE_INTERRUPTIBLE : 0);
    124
    125	state = drm_atomic_state_alloc(fb->dev);
    126	if (!state) {
    127		ret = -ENOMEM;
    128		goto out_drop_locks;
    129	}
    130	state->acquire_ctx = &ctx;
    131
    132	if (clips) {
    133		uint32_t inc = 1;
    134
    135		if (flags & DRM_MODE_FB_DIRTY_ANNOTATE_COPY) {
    136			inc = 2;
    137			num_clips /= 2;
    138		}
    139
    140		rects = kcalloc(num_clips, sizeof(*rects), GFP_KERNEL);
    141		if (!rects) {
    142			ret = -ENOMEM;
    143			goto out;
    144		}
    145
    146		convert_clip_rect_to_rect(clips, rects, num_clips, inc);
    147		damage = drm_property_create_blob(fb->dev,
    148						  num_clips * sizeof(*rects),
    149						  rects);
    150		if (IS_ERR(damage)) {
    151			ret = PTR_ERR(damage);
    152			damage = NULL;
    153			goto out;
    154		}
    155	}
    156
    157retry:
    158	drm_for_each_plane(plane, fb->dev) {
    159		struct drm_plane_state *plane_state;
    160
    161		ret = drm_modeset_lock(&plane->mutex, state->acquire_ctx);
    162		if (ret)
    163			goto out;
    164
    165		if (plane->state->fb != fb) {
    166			drm_modeset_unlock(&plane->mutex);
    167			continue;
    168		}
    169
    170		plane_state = drm_atomic_get_plane_state(state, plane);
    171		if (IS_ERR(plane_state)) {
    172			ret = PTR_ERR(plane_state);
    173			goto out;
    174		}
    175
    176		drm_property_replace_blob(&plane_state->fb_damage_clips,
    177					  damage);
    178	}
    179
    180	ret = drm_atomic_commit(state);
    181
    182out:
    183	if (ret == -EDEADLK) {
    184		drm_atomic_state_clear(state);
    185		ret = drm_modeset_backoff(&ctx);
    186		if (!ret)
    187			goto retry;
    188	}
    189
    190	drm_property_blob_put(damage);
    191	kfree(rects);
    192	drm_atomic_state_put(state);
    193
    194out_drop_locks:
    195	drm_modeset_drop_locks(&ctx);
    196	drm_modeset_acquire_fini(&ctx);
    197
    198	return ret;
    199
    200}
    201EXPORT_SYMBOL(drm_atomic_helper_dirtyfb);
    202
    203/**
    204 * drm_atomic_helper_damage_iter_init - Initialize the damage iterator.
    205 * @iter: The iterator to initialize.
    206 * @old_state: Old plane state for validation.
    207 * @state: Plane state from which to iterate the damage clips.
    208 *
    209 * Initialize an iterator, which clips plane damage
    210 * &drm_plane_state.fb_damage_clips to plane &drm_plane_state.src. This iterator
    211 * returns full plane src in case damage is not present because either
    212 * user-space didn't sent or driver discarded it (it want to do full plane
    213 * update). Currently this iterator returns full plane src in case plane src
    214 * changed but that can be changed in future to return damage.
    215 *
    216 * For the case when plane is not visible or plane update should not happen the
    217 * first call to iter_next will return false. Note that this helper use clipped
    218 * &drm_plane_state.src, so driver calling this helper should have called
    219 * drm_atomic_helper_check_plane_state() earlier.
    220 */
    221void
    222drm_atomic_helper_damage_iter_init(struct drm_atomic_helper_damage_iter *iter,
    223				   const struct drm_plane_state *old_state,
    224				   const struct drm_plane_state *state)
    225{
    226	memset(iter, 0, sizeof(*iter));
    227
    228	if (!state || !state->crtc || !state->fb || !state->visible)
    229		return;
    230
    231	iter->clips = (struct drm_rect *)drm_plane_get_damage_clips(state);
    232	iter->num_clips = drm_plane_get_damage_clips_count(state);
    233
    234	/* Round down for x1/y1 and round up for x2/y2 to catch all pixels */
    235	iter->plane_src.x1 = state->src.x1 >> 16;
    236	iter->plane_src.y1 = state->src.y1 >> 16;
    237	iter->plane_src.x2 = (state->src.x2 >> 16) + !!(state->src.x2 & 0xFFFF);
    238	iter->plane_src.y2 = (state->src.y2 >> 16) + !!(state->src.y2 & 0xFFFF);
    239
    240	if (!iter->clips || !drm_rect_equals(&state->src, &old_state->src)) {
    241		iter->clips = NULL;
    242		iter->num_clips = 0;
    243		iter->full_update = true;
    244	}
    245}
    246EXPORT_SYMBOL(drm_atomic_helper_damage_iter_init);
    247
    248/**
    249 * drm_atomic_helper_damage_iter_next - Advance the damage iterator.
    250 * @iter: The iterator to advance.
    251 * @rect: Return a rectangle in fb coordinate clipped to plane src.
    252 *
    253 * Since plane src is in 16.16 fixed point and damage clips are whole number,
    254 * this iterator round off clips that intersect with plane src. Round down for
    255 * x1/y1 and round up for x2/y2 for the intersected coordinate. Similar rounding
    256 * off for full plane src, in case it's returned as damage. This iterator will
    257 * skip damage clips outside of plane src.
    258 *
    259 * Return: True if the output is valid, false if reached the end.
    260 *
    261 * If the first call to iterator next returns false then it means no need to
    262 * update the plane.
    263 */
    264bool
    265drm_atomic_helper_damage_iter_next(struct drm_atomic_helper_damage_iter *iter,
    266				   struct drm_rect *rect)
    267{
    268	bool ret = false;
    269
    270	if (iter->full_update) {
    271		*rect = iter->plane_src;
    272		iter->full_update = false;
    273		return true;
    274	}
    275
    276	while (iter->curr_clip < iter->num_clips) {
    277		*rect = iter->clips[iter->curr_clip];
    278		iter->curr_clip++;
    279
    280		if (drm_rect_intersect(rect, &iter->plane_src)) {
    281			ret = true;
    282			break;
    283		}
    284	}
    285
    286	return ret;
    287}
    288EXPORT_SYMBOL(drm_atomic_helper_damage_iter_next);
    289
    290/**
    291 * drm_atomic_helper_damage_merged - Merged plane damage
    292 * @old_state: Old plane state for validation.
    293 * @state: Plane state from which to iterate the damage clips.
    294 * @rect: Returns the merged damage rectangle
    295 *
    296 * This function merges any valid plane damage clips into one rectangle and
    297 * returns it in @rect.
    298 *
    299 * For details see: drm_atomic_helper_damage_iter_init() and
    300 * drm_atomic_helper_damage_iter_next().
    301 *
    302 * Returns:
    303 * True if there is valid plane damage otherwise false.
    304 */
    305bool drm_atomic_helper_damage_merged(const struct drm_plane_state *old_state,
    306				     struct drm_plane_state *state,
    307				     struct drm_rect *rect)
    308{
    309	struct drm_atomic_helper_damage_iter iter;
    310	struct drm_rect clip;
    311	bool valid = false;
    312
    313	rect->x1 = INT_MAX;
    314	rect->y1 = INT_MAX;
    315	rect->x2 = 0;
    316	rect->y2 = 0;
    317
    318	drm_atomic_helper_damage_iter_init(&iter, old_state, state);
    319	drm_atomic_for_each_plane_damage(&iter, &clip) {
    320		rect->x1 = min(rect->x1, clip.x1);
    321		rect->y1 = min(rect->y1, clip.y1);
    322		rect->x2 = max(rect->x2, clip.x2);
    323		rect->y2 = max(rect->y2, clip.y2);
    324		valid = true;
    325	}
    326
    327	return valid;
    328}
    329EXPORT_SYMBOL(drm_atomic_helper_damage_merged);