linux_dsm_epyc7002/drivers/gpu/drm/vkms/vkms_crtc.c
Kangjie Lu 208c6e8cff drm: vkms: check status of alloc_ordered_workqueue
alloc_ordered_workqueue may fail and return NULL.
The fix returns ENOMEM when it fails to avoid potential NULL
pointer dereference.

Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20190309043628.6078-1-kjlu@umn.edu
2019-03-25 09:33:42 +01:00

227 lines
6.0 KiB
C

// SPDX-License-Identifier: GPL-2.0+
#include "vkms_drv.h"
#include <drm/drm_atomic_helper.h>
#include <drm/drm_probe_helper.h>
static enum hrtimer_restart vkms_vblank_simulate(struct hrtimer *timer)
{
struct vkms_output *output = container_of(timer, struct vkms_output,
vblank_hrtimer);
struct drm_crtc *crtc = &output->crtc;
struct vkms_crtc_state *state = to_vkms_crtc_state(crtc->state);
u64 ret_overrun;
bool ret;
spin_lock(&output->lock);
ret = drm_crtc_handle_vblank(crtc);
if (!ret)
DRM_ERROR("vkms failure on handling vblank");
if (state && output->crc_enabled) {
u64 frame = drm_crtc_accurate_vblank_count(crtc);
/* update frame_start only if a queued vkms_crc_work_handle()
* has read the data
*/
spin_lock(&output->state_lock);
if (!state->frame_start)
state->frame_start = frame;
spin_unlock(&output->state_lock);
ret = queue_work(output->crc_workq, &state->crc_work);
if (!ret)
DRM_WARN("failed to queue vkms_crc_work_handle");
}
ret_overrun = hrtimer_forward_now(&output->vblank_hrtimer,
output->period_ns);
WARN_ON(ret_overrun != 1);
spin_unlock(&output->lock);
return HRTIMER_RESTART;
}
static int vkms_enable_vblank(struct drm_crtc *crtc)
{
struct drm_device *dev = crtc->dev;
unsigned int pipe = drm_crtc_index(crtc);
struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
drm_calc_timestamping_constants(crtc, &crtc->mode);
hrtimer_init(&out->vblank_hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
out->vblank_hrtimer.function = &vkms_vblank_simulate;
out->period_ns = ktime_set(0, vblank->framedur_ns);
hrtimer_start(&out->vblank_hrtimer, out->period_ns, HRTIMER_MODE_REL);
return 0;
}
static void vkms_disable_vblank(struct drm_crtc *crtc)
{
struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
hrtimer_cancel(&out->vblank_hrtimer);
}
bool vkms_get_vblank_timestamp(struct drm_device *dev, unsigned int pipe,
int *max_error, ktime_t *vblank_time,
bool in_vblank_irq)
{
struct vkms_device *vkmsdev = drm_device_to_vkms_device(dev);
struct vkms_output *output = &vkmsdev->output;
*vblank_time = output->vblank_hrtimer.node.expires;
if (!in_vblank_irq)
*vblank_time -= output->period_ns;
return true;
}
static void vkms_atomic_crtc_reset(struct drm_crtc *crtc)
{
struct vkms_crtc_state *vkms_state = NULL;
if (crtc->state) {
vkms_state = to_vkms_crtc_state(crtc->state);
__drm_atomic_helper_crtc_destroy_state(crtc->state);
kfree(vkms_state);
crtc->state = NULL;
}
vkms_state = kzalloc(sizeof(*vkms_state), GFP_KERNEL);
if (!vkms_state)
return;
INIT_WORK(&vkms_state->crc_work, vkms_crc_work_handle);
crtc->state = &vkms_state->base;
crtc->state->crtc = crtc;
}
static struct drm_crtc_state *
vkms_atomic_crtc_duplicate_state(struct drm_crtc *crtc)
{
struct vkms_crtc_state *vkms_state;
if (WARN_ON(!crtc->state))
return NULL;
vkms_state = kzalloc(sizeof(*vkms_state), GFP_KERNEL);
if (!vkms_state)
return NULL;
__drm_atomic_helper_crtc_duplicate_state(crtc, &vkms_state->base);
INIT_WORK(&vkms_state->crc_work, vkms_crc_work_handle);
return &vkms_state->base;
}
static void vkms_atomic_crtc_destroy_state(struct drm_crtc *crtc,
struct drm_crtc_state *state)
{
struct vkms_crtc_state *vkms_state = to_vkms_crtc_state(state);
__drm_atomic_helper_crtc_destroy_state(state);
if (vkms_state) {
flush_work(&vkms_state->crc_work);
kfree(vkms_state);
}
}
static const struct drm_crtc_funcs vkms_crtc_funcs = {
.set_config = drm_atomic_helper_set_config,
.destroy = drm_crtc_cleanup,
.page_flip = drm_atomic_helper_page_flip,
.reset = vkms_atomic_crtc_reset,
.atomic_duplicate_state = vkms_atomic_crtc_duplicate_state,
.atomic_destroy_state = vkms_atomic_crtc_destroy_state,
.enable_vblank = vkms_enable_vblank,
.disable_vblank = vkms_disable_vblank,
.set_crc_source = vkms_set_crc_source,
.verify_crc_source = vkms_verify_crc_source,
};
static void vkms_crtc_atomic_enable(struct drm_crtc *crtc,
struct drm_crtc_state *old_state)
{
drm_crtc_vblank_on(crtc);
}
static void vkms_crtc_atomic_disable(struct drm_crtc *crtc,
struct drm_crtc_state *old_state)
{
drm_crtc_vblank_off(crtc);
}
static void vkms_crtc_atomic_begin(struct drm_crtc *crtc,
struct drm_crtc_state *old_crtc_state)
{
struct vkms_output *vkms_output = drm_crtc_to_vkms_output(crtc);
/* This lock is held across the atomic commit to block vblank timer
* from scheduling vkms_crc_work_handle until the crc_data is updated
*/
spin_lock_irq(&vkms_output->lock);
}
static void vkms_crtc_atomic_flush(struct drm_crtc *crtc,
struct drm_crtc_state *old_crtc_state)
{
struct vkms_output *vkms_output = drm_crtc_to_vkms_output(crtc);
unsigned long flags;
if (crtc->state->event) {
spin_lock_irqsave(&crtc->dev->event_lock, flags);
if (drm_crtc_vblank_get(crtc) != 0)
drm_crtc_send_vblank_event(crtc, crtc->state->event);
else
drm_crtc_arm_vblank_event(crtc, crtc->state->event);
spin_unlock_irqrestore(&crtc->dev->event_lock, flags);
crtc->state->event = NULL;
}
spin_unlock_irq(&vkms_output->lock);
}
static const struct drm_crtc_helper_funcs vkms_crtc_helper_funcs = {
.atomic_begin = vkms_crtc_atomic_begin,
.atomic_flush = vkms_crtc_atomic_flush,
.atomic_enable = vkms_crtc_atomic_enable,
.atomic_disable = vkms_crtc_atomic_disable,
};
int vkms_crtc_init(struct drm_device *dev, struct drm_crtc *crtc,
struct drm_plane *primary, struct drm_plane *cursor)
{
struct vkms_output *vkms_out = drm_crtc_to_vkms_output(crtc);
int ret;
ret = drm_crtc_init_with_planes(dev, crtc, primary, cursor,
&vkms_crtc_funcs, NULL);
if (ret) {
DRM_ERROR("Failed to init CRTC\n");
return ret;
}
drm_crtc_helper_add(crtc, &vkms_crtc_helper_funcs);
spin_lock_init(&vkms_out->lock);
spin_lock_init(&vkms_out->state_lock);
vkms_out->crc_workq = alloc_ordered_workqueue("vkms_crc_workq", 0);
if (!vkms_out->crc_workq)
return -ENOMEM;
return ret;
}