kernel-fxtec-pro1x/drivers/gpu/drm/drm_rect.c
Ville Syrjälä f2c1ddb873 drm/rect: Avoid division by zero
commit 433480c1afd44f3e1e664b85063d98cefeefa0ed upstream.

Check for zero width/height destination rectangle in
drm_rect_clip_scaled() to avoid a division by zero.

Cc: stable@vger.kernel.org
Fixes: f96bdf564f ("drm/rect: Handle rounding errors in drm_rect_clip_scaled, v3.")
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Benjamin Gaignard <benjamin.gaignard@st.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Testcase: igt/kms_selftest/drm_rect_clip_scaled_div_by_zero
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191122175623.13565-2-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11 04:34:07 -08:00

476 lines
12 KiB
C

/*
* Copyright (C) 2011-2013 Intel Corporation
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <linux/errno.h>
#include <linux/export.h>
#include <linux/kernel.h>
#include <drm/drmP.h>
#include <drm/drm_rect.h>
/**
* drm_rect_intersect - intersect two rectangles
* @r1: first rectangle
* @r2: second rectangle
*
* Calculate the intersection of rectangles @r1 and @r2.
* @r1 will be overwritten with the intersection.
*
* RETURNS:
* %true if rectangle @r1 is still visible after the operation,
* %false otherwise.
*/
bool drm_rect_intersect(struct drm_rect *r1, const struct drm_rect *r2)
{
r1->x1 = max(r1->x1, r2->x1);
r1->y1 = max(r1->y1, r2->y1);
r1->x2 = min(r1->x2, r2->x2);
r1->y2 = min(r1->y2, r2->y2);
return drm_rect_visible(r1);
}
EXPORT_SYMBOL(drm_rect_intersect);
static u32 clip_scaled(u32 src, u32 dst, u32 clip)
{
u64 tmp;
if (dst == 0)
return 0;
tmp = mul_u32_u32(src, dst - clip);
/*
* Round toward 1.0 when clipping so that we don't accidentally
* change upscaling to downscaling or vice versa.
*/
if (src < (dst << 16))
return DIV_ROUND_UP_ULL(tmp, dst);
else
return DIV_ROUND_DOWN_ULL(tmp, dst);
}
/**
* drm_rect_clip_scaled - perform a scaled clip operation
* @src: source window rectangle
* @dst: destination window rectangle
* @clip: clip rectangle
*
* Clip rectangle @dst by rectangle @clip. Clip rectangle @src by the
* same amounts multiplied by @hscale and @vscale.
*
* RETURNS:
* %true if rectangle @dst is still visible after being clipped,
* %false otherwise
*/
bool drm_rect_clip_scaled(struct drm_rect *src, struct drm_rect *dst,
const struct drm_rect *clip)
{
int diff;
diff = clip->x1 - dst->x1;
if (diff > 0) {
u32 new_src_w = clip_scaled(drm_rect_width(src),
drm_rect_width(dst), diff);
src->x1 = clamp_t(int64_t, src->x2 - new_src_w, INT_MIN, INT_MAX);
dst->x1 = clip->x1;
}
diff = clip->y1 - dst->y1;
if (diff > 0) {
u32 new_src_h = clip_scaled(drm_rect_height(src),
drm_rect_height(dst), diff);
src->y1 = clamp_t(int64_t, src->y2 - new_src_h, INT_MIN, INT_MAX);
dst->y1 = clip->y1;
}
diff = dst->x2 - clip->x2;
if (diff > 0) {
u32 new_src_w = clip_scaled(drm_rect_width(src),
drm_rect_width(dst), diff);
src->x2 = clamp_t(int64_t, src->x1 + new_src_w, INT_MIN, INT_MAX);
dst->x2 = clip->x2;
}
diff = dst->y2 - clip->y2;
if (diff > 0) {
u32 new_src_h = clip_scaled(drm_rect_height(src),
drm_rect_height(dst), diff);
src->y2 = clamp_t(int64_t, src->y1 + new_src_h, INT_MIN, INT_MAX);
dst->y2 = clip->y2;
}
return drm_rect_visible(dst);
}
EXPORT_SYMBOL(drm_rect_clip_scaled);
static int drm_calc_scale(int src, int dst)
{
int scale = 0;
if (WARN_ON(src < 0 || dst < 0))
return -EINVAL;
if (dst == 0)
return 0;
if (src > (dst << 16))
return DIV_ROUND_UP(src, dst);
else
scale = src / dst;
return scale;
}
/**
* drm_rect_calc_hscale - calculate the horizontal scaling factor
* @src: source window rectangle
* @dst: destination window rectangle
* @min_hscale: minimum allowed horizontal scaling factor
* @max_hscale: maximum allowed horizontal scaling factor
*
* Calculate the horizontal scaling factor as
* (@src width) / (@dst width).
*
* If the scale is below 1 << 16, round down. If the scale is above
* 1 << 16, round up. This will calculate the scale with the most
* pessimistic limit calculation.
*
* RETURNS:
* The horizontal scaling factor, or errno of out of limits.
*/
int drm_rect_calc_hscale(const struct drm_rect *src,
const struct drm_rect *dst,
int min_hscale, int max_hscale)
{
int src_w = drm_rect_width(src);
int dst_w = drm_rect_width(dst);
int hscale = drm_calc_scale(src_w, dst_w);
if (hscale < 0 || dst_w == 0)
return hscale;
if (hscale < min_hscale || hscale > max_hscale)
return -ERANGE;
return hscale;
}
EXPORT_SYMBOL(drm_rect_calc_hscale);
/**
* drm_rect_calc_vscale - calculate the vertical scaling factor
* @src: source window rectangle
* @dst: destination window rectangle
* @min_vscale: minimum allowed vertical scaling factor
* @max_vscale: maximum allowed vertical scaling factor
*
* Calculate the vertical scaling factor as
* (@src height) / (@dst height).
*
* If the scale is below 1 << 16, round down. If the scale is above
* 1 << 16, round up. This will calculate the scale with the most
* pessimistic limit calculation.
*
* RETURNS:
* The vertical scaling factor, or errno of out of limits.
*/
int drm_rect_calc_vscale(const struct drm_rect *src,
const struct drm_rect *dst,
int min_vscale, int max_vscale)
{
int src_h = drm_rect_height(src);
int dst_h = drm_rect_height(dst);
int vscale = drm_calc_scale(src_h, dst_h);
if (vscale < 0 || dst_h == 0)
return vscale;
if (vscale < min_vscale || vscale > max_vscale)
return -ERANGE;
return vscale;
}
EXPORT_SYMBOL(drm_rect_calc_vscale);
/**
* drm_calc_hscale_relaxed - calculate the horizontal scaling factor
* @src: source window rectangle
* @dst: destination window rectangle
* @min_hscale: minimum allowed horizontal scaling factor
* @max_hscale: maximum allowed horizontal scaling factor
*
* Calculate the horizontal scaling factor as
* (@src width) / (@dst width).
*
* If the calculated scaling factor is below @min_vscale,
* decrease the height of rectangle @dst to compensate.
*
* If the calculated scaling factor is above @max_vscale,
* decrease the height of rectangle @src to compensate.
*
* If the scale is below 1 << 16, round down. If the scale is above
* 1 << 16, round up. This will calculate the scale with the most
* pessimistic limit calculation.
*
* RETURNS:
* The horizontal scaling factor.
*/
int drm_rect_calc_hscale_relaxed(struct drm_rect *src,
struct drm_rect *dst,
int min_hscale, int max_hscale)
{
int src_w = drm_rect_width(src);
int dst_w = drm_rect_width(dst);
int hscale = drm_calc_scale(src_w, dst_w);
if (hscale < 0 || dst_w == 0)
return hscale;
if (hscale < min_hscale) {
int max_dst_w = src_w / min_hscale;
drm_rect_adjust_size(dst, max_dst_w - dst_w, 0);
return min_hscale;
}
if (hscale > max_hscale) {
int max_src_w = dst_w * max_hscale;
drm_rect_adjust_size(src, max_src_w - src_w, 0);
return max_hscale;
}
return hscale;
}
EXPORT_SYMBOL(drm_rect_calc_hscale_relaxed);
/**
* drm_rect_calc_vscale_relaxed - calculate the vertical scaling factor
* @src: source window rectangle
* @dst: destination window rectangle
* @min_vscale: minimum allowed vertical scaling factor
* @max_vscale: maximum allowed vertical scaling factor
*
* Calculate the vertical scaling factor as
* (@src height) / (@dst height).
*
* If the calculated scaling factor is below @min_vscale,
* decrease the height of rectangle @dst to compensate.
*
* If the calculated scaling factor is above @max_vscale,
* decrease the height of rectangle @src to compensate.
*
* If the scale is below 1 << 16, round down. If the scale is above
* 1 << 16, round up. This will calculate the scale with the most
* pessimistic limit calculation.
*
* RETURNS:
* The vertical scaling factor.
*/
int drm_rect_calc_vscale_relaxed(struct drm_rect *src,
struct drm_rect *dst,
int min_vscale, int max_vscale)
{
int src_h = drm_rect_height(src);
int dst_h = drm_rect_height(dst);
int vscale = drm_calc_scale(src_h, dst_h);
if (vscale < 0 || dst_h == 0)
return vscale;
if (vscale < min_vscale) {
int max_dst_h = src_h / min_vscale;
drm_rect_adjust_size(dst, 0, max_dst_h - dst_h);
return min_vscale;
}
if (vscale > max_vscale) {
int max_src_h = dst_h * max_vscale;
drm_rect_adjust_size(src, 0, max_src_h - src_h);
return max_vscale;
}
return vscale;
}
EXPORT_SYMBOL(drm_rect_calc_vscale_relaxed);
/**
* drm_rect_debug_print - print the rectangle information
* @prefix: prefix string
* @r: rectangle to print
* @fixed_point: rectangle is in 16.16 fixed point format
*/
void drm_rect_debug_print(const char *prefix, const struct drm_rect *r, bool fixed_point)
{
if (fixed_point)
DRM_DEBUG_KMS("%s" DRM_RECT_FP_FMT "\n", prefix, DRM_RECT_FP_ARG(r));
else
DRM_DEBUG_KMS("%s" DRM_RECT_FMT "\n", prefix, DRM_RECT_ARG(r));
}
EXPORT_SYMBOL(drm_rect_debug_print);
/**
* drm_rect_rotate - Rotate the rectangle
* @r: rectangle to be rotated
* @width: Width of the coordinate space
* @height: Height of the coordinate space
* @rotation: Transformation to be applied
*
* Apply @rotation to the coordinates of rectangle @r.
*
* @width and @height combined with @rotation define
* the location of the new origin.
*
* @width correcsponds to the horizontal and @height
* to the vertical axis of the untransformed coordinate
* space.
*/
void drm_rect_rotate(struct drm_rect *r,
int width, int height,
unsigned int rotation)
{
struct drm_rect tmp;
if (rotation & (DRM_MODE_REFLECT_X | DRM_MODE_REFLECT_Y)) {
tmp = *r;
if (rotation & DRM_MODE_REFLECT_X) {
r->x1 = width - tmp.x2;
r->x2 = width - tmp.x1;
}
if (rotation & DRM_MODE_REFLECT_Y) {
r->y1 = height - tmp.y2;
r->y2 = height - tmp.y1;
}
}
switch (rotation & DRM_MODE_ROTATE_MASK) {
case DRM_MODE_ROTATE_0:
break;
case DRM_MODE_ROTATE_90:
tmp = *r;
r->x1 = tmp.y1;
r->x2 = tmp.y2;
r->y1 = width - tmp.x2;
r->y2 = width - tmp.x1;
break;
case DRM_MODE_ROTATE_180:
tmp = *r;
r->x1 = width - tmp.x2;
r->x2 = width - tmp.x1;
r->y1 = height - tmp.y2;
r->y2 = height - tmp.y1;
break;
case DRM_MODE_ROTATE_270:
tmp = *r;
r->x1 = height - tmp.y2;
r->x2 = height - tmp.y1;
r->y1 = tmp.x1;
r->y2 = tmp.x2;
break;
default:
break;
}
}
EXPORT_SYMBOL(drm_rect_rotate);
/**
* drm_rect_rotate_inv - Inverse rotate the rectangle
* @r: rectangle to be rotated
* @width: Width of the coordinate space
* @height: Height of the coordinate space
* @rotation: Transformation whose inverse is to be applied
*
* Apply the inverse of @rotation to the coordinates
* of rectangle @r.
*
* @width and @height combined with @rotation define
* the location of the new origin.
*
* @width correcsponds to the horizontal and @height
* to the vertical axis of the original untransformed
* coordinate space, so that you never have to flip
* them when doing a rotatation and its inverse.
* That is, if you do ::
*
* drm_rect_rotate(&r, width, height, rotation);
* drm_rect_rotate_inv(&r, width, height, rotation);
*
* you will always get back the original rectangle.
*/
void drm_rect_rotate_inv(struct drm_rect *r,
int width, int height,
unsigned int rotation)
{
struct drm_rect tmp;
switch (rotation & DRM_MODE_ROTATE_MASK) {
case DRM_MODE_ROTATE_0:
break;
case DRM_MODE_ROTATE_90:
tmp = *r;
r->x1 = width - tmp.y2;
r->x2 = width - tmp.y1;
r->y1 = tmp.x1;
r->y2 = tmp.x2;
break;
case DRM_MODE_ROTATE_180:
tmp = *r;
r->x1 = width - tmp.x2;
r->x2 = width - tmp.x1;
r->y1 = height - tmp.y2;
r->y2 = height - tmp.y1;
break;
case DRM_MODE_ROTATE_270:
tmp = *r;
r->x1 = tmp.y1;
r->x2 = tmp.y2;
r->y1 = height - tmp.x2;
r->y2 = height - tmp.x1;
break;
default:
break;
}
if (rotation & (DRM_MODE_REFLECT_X | DRM_MODE_REFLECT_Y)) {
tmp = *r;
if (rotation & DRM_MODE_REFLECT_X) {
r->x1 = width - tmp.x2;
r->x2 = width - tmp.x1;
}
if (rotation & DRM_MODE_REFLECT_Y) {
r->y1 = height - tmp.y2;
r->y2 = height - tmp.y1;
}
}
}
EXPORT_SYMBOL(drm_rect_rotate_inv);