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robclarkdanvet
robclark
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danvet
committed
drm: Atomic modeset ioctl
The atomic modeset ioctl can be used to push any number of new values for object properties. The driver can then check the full device configuration as single unit, and try to apply the changes atomically. The ioctl simply takes a list of object IDs and property IDs and their values. Originally based on a patch from Ville Syrjälä, although it has mutated (mutilated?) enough since then that you probably shouldn't blame it on him ;-) The atomic support is hidden behind the DRM_CLIENT_CAP_ATOMIC cap (to protect legacy userspace) and drm.atomic module param (for now). v2: Check for file_priv->atomic to make sure we only allow userspace in-the-know to use atomic. Signed-off-by: Rob Clark <robdclark@gmail.com> Reviewed-by: Sean Paul <seanpaul@chromium.org> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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-4
lines changed

6 files changed

+366
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lines changed

‎drivers/gpu/drm/drm_atomic.c

Lines changed: 331 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -56,6 +56,11 @@ drm_atomic_state_alloc(struct drm_device *dev)
5656
if (!state)
5757
return NULL;
5858

59+
/* TODO legacy paths should maybe do a better job about
60+
* setting this appropriately?
61+
*/
62+
state->allow_modeset = true;
63+
5964
state->num_connector = ACCESS_ONCE(dev->mode_config.num_connector);
6065

6166
state->crtcs = kcalloc(dev->mode_config.num_crtc,
@@ -1003,6 +1008,22 @@ int drm_atomic_check_only(struct drm_atomic_state *state)
10031008
if (config->funcs->atomic_check)
10041009
ret = config->funcs->atomic_check(state->dev, state);
10051010

1011+
if (!state->allow_modeset) {
1012+
for (i = 0; i < ncrtcs; i++) {
1013+
struct drm_crtc *crtc = state->crtcs[i];
1014+
struct drm_crtc_state *crtc_state = state->crtc_states[i];
1015+
1016+
if (!crtc)
1017+
continue;
1018+
1019+
if (crtc_state->mode_changed) {
1020+
DRM_DEBUG_KMS("[CRTC:%d] requires full modeset\n",
1021+
crtc->base.id);
1022+
return -EINVAL;
1023+
}
1024+
}
1025+
}
1026+
10061027
return ret;
10071028
}
10081029
EXPORT_SYMBOL(drm_atomic_check_only);
@@ -1068,3 +1089,313 @@ int drm_atomic_async_commit(struct drm_atomic_state *state)
10681089
return config->funcs->atomic_commit(state->dev, state, true);
10691090
}
10701091
EXPORT_SYMBOL(drm_atomic_async_commit);
1092+
1093+
/*
1094+
* The big monstor ioctl
1095+
*/
1096+
1097+
static struct drm_pending_vblank_event *create_vblank_event(
1098+
struct drm_device *dev, struct drm_file *file_priv, uint64_t user_data)
1099+
{
1100+
struct drm_pending_vblank_event *e = NULL;
1101+
unsigned long flags;
1102+
1103+
spin_lock_irqsave(&dev->event_lock, flags);
1104+
if (file_priv->event_space < sizeof e->event) {
1105+
spin_unlock_irqrestore(&dev->event_lock, flags);
1106+
goto out;
1107+
}
1108+
file_priv->event_space -= sizeof e->event;
1109+
spin_unlock_irqrestore(&dev->event_lock, flags);
1110+
1111+
e = kzalloc(sizeof *e, GFP_KERNEL);
1112+
if (e == NULL) {
1113+
spin_lock_irqsave(&dev->event_lock, flags);
1114+
file_priv->event_space += sizeof e->event;
1115+
spin_unlock_irqrestore(&dev->event_lock, flags);
1116+
goto out;
1117+
}
1118+
1119+
e->event.base.type = DRM_EVENT_FLIP_COMPLETE;
1120+
e->event.base.length = sizeof e->event;
1121+
e->event.user_data = user_data;
1122+
e->base.event = &e->event.base;
1123+
e->base.file_priv = file_priv;
1124+
e->base.destroy = (void (*) (struct drm_pending_event *)) kfree;
1125+
1126+
out:
1127+
return e;
1128+
}
1129+
1130+
static void destroy_vblank_event(struct drm_device *dev,
1131+
struct drm_file *file_priv, struct drm_pending_vblank_event *e)
1132+
{
1133+
unsigned long flags;
1134+
1135+
spin_lock_irqsave(&dev->event_lock, flags);
1136+
file_priv->event_space += sizeof e->event;
1137+
spin_unlock_irqrestore(&dev->event_lock, flags);
1138+
kfree(e);
1139+
}
1140+
1141+
static int atomic_set_prop(struct drm_atomic_state *state,
1142+
struct drm_mode_object *obj, struct drm_property *prop,
1143+
uint64_t prop_value)
1144+
{
1145+
struct drm_mode_object *ref;
1146+
int ret;
1147+
1148+
if (!drm_property_change_valid_get(prop, prop_value, &ref))
1149+
return -EINVAL;
1150+
1151+
switch (obj->type) {
1152+
case DRM_MODE_OBJECT_CONNECTOR: {
1153+
struct drm_connector *connector = obj_to_connector(obj);
1154+
struct drm_connector_state *connector_state;
1155+
1156+
connector_state = drm_atomic_get_connector_state(state, connector);
1157+
if (IS_ERR(connector_state)) {
1158+
ret = PTR_ERR(connector_state);
1159+
break;
1160+
}
1161+
1162+
ret = drm_atomic_connector_set_property(connector,
1163+
connector_state, prop, prop_value);
1164+
break;
1165+
}
1166+
case DRM_MODE_OBJECT_CRTC: {
1167+
struct drm_crtc *crtc = obj_to_crtc(obj);
1168+
struct drm_crtc_state *crtc_state;
1169+
1170+
crtc_state = drm_atomic_get_crtc_state(state, crtc);
1171+
if (IS_ERR(crtc_state)) {
1172+
ret = PTR_ERR(crtc_state);
1173+
break;
1174+
}
1175+
1176+
ret = drm_atomic_crtc_set_property(crtc,
1177+
crtc_state, prop, prop_value);
1178+
break;
1179+
}
1180+
case DRM_MODE_OBJECT_PLANE: {
1181+
struct drm_plane *plane = obj_to_plane(obj);
1182+
struct drm_plane_state *plane_state;
1183+
1184+
plane_state = drm_atomic_get_plane_state(state, plane);
1185+
if (IS_ERR(plane_state)) {
1186+
ret = PTR_ERR(plane_state);
1187+
break;
1188+
}
1189+
1190+
ret = drm_atomic_plane_set_property(plane,
1191+
plane_state, prop, prop_value);
1192+
break;
1193+
}
1194+
default:
1195+
ret = -EINVAL;
1196+
break;
1197+
}
1198+
1199+
drm_property_change_valid_put(prop, ref);
1200+
return ret;
1201+
}
1202+
1203+
int drm_mode_atomic_ioctl(struct drm_device *dev,
1204+
void *data, struct drm_file *file_priv)
1205+
{
1206+
struct drm_mode_atomic *arg = data;
1207+
uint32_t __user *objs_ptr = (uint32_t __user *)(unsigned long)(arg->objs_ptr);
1208+
uint32_t __user *count_props_ptr = (uint32_t __user *)(unsigned long)(arg->count_props_ptr);
1209+
uint32_t __user *props_ptr = (uint32_t __user *)(unsigned long)(arg->props_ptr);
1210+
uint64_t __user *prop_values_ptr = (uint64_t __user *)(unsigned long)(arg->prop_values_ptr);
1211+
unsigned int copied_objs, copied_props;
1212+
struct drm_atomic_state *state;
1213+
struct drm_modeset_acquire_ctx ctx;
1214+
struct drm_plane *plane;
1215+
unsigned plane_mask = 0;
1216+
int ret = 0;
1217+
unsigned int i, j;
1218+
1219+
/* disallow for drivers not supporting atomic: */
1220+
if (!drm_core_check_feature(dev, DRIVER_ATOMIC))
1221+
return -EINVAL;
1222+
1223+
/* disallow for userspace that has not enabled atomic cap (even
1224+
* though this may be a bit overkill, since legacy userspace
1225+
* wouldn't know how to call this ioctl)
1226+
*/
1227+
if (!file_priv->atomic)
1228+
return -EINVAL;
1229+
1230+
if (arg->flags & ~DRM_MODE_ATOMIC_FLAGS)
1231+
return -EINVAL;
1232+
1233+
if (arg->reserved)
1234+
return -EINVAL;
1235+
1236+
if ((arg->flags & DRM_MODE_PAGE_FLIP_ASYNC) &&
1237+
!dev->mode_config.async_page_flip)
1238+
return -EINVAL;
1239+
1240+
/* can't test and expect an event at the same time. */
1241+
if ((arg->flags & DRM_MODE_ATOMIC_TEST_ONLY) &&
1242+
(arg->flags & DRM_MODE_PAGE_FLIP_EVENT))
1243+
return -EINVAL;
1244+
1245+
drm_modeset_acquire_init(&ctx, 0);
1246+
1247+
state = drm_atomic_state_alloc(dev);
1248+
if (!state)
1249+
return -ENOMEM;
1250+
1251+
state->acquire_ctx = &ctx;
1252+
state->allow_modeset = !!(arg->flags & DRM_MODE_ATOMIC_ALLOW_MODESET);
1253+
1254+
retry:
1255+
copied_objs = 0;
1256+
copied_props = 0;
1257+
1258+
for (i = 0; i < arg->count_objs; i++) {
1259+
uint32_t obj_id, count_props;
1260+
struct drm_mode_object *obj;
1261+
1262+
if (get_user(obj_id, objs_ptr + copied_objs)) {
1263+
ret = -EFAULT;
1264+
goto fail;
1265+
}
1266+
1267+
obj = drm_mode_object_find(dev, obj_id, DRM_MODE_OBJECT_ANY);
1268+
if (!obj || !obj->properties) {
1269+
ret = -ENOENT;
1270+
goto fail;
1271+
}
1272+
1273+
if (obj->type == DRM_MODE_OBJECT_PLANE) {
1274+
plane = obj_to_plane(obj);
1275+
plane_mask |= (1 << drm_plane_index(plane));
1276+
plane->old_fb = plane->fb;
1277+
}
1278+
1279+
if (get_user(count_props, count_props_ptr + copied_objs)) {
1280+
ret = -EFAULT;
1281+
goto fail;
1282+
}
1283+
1284+
copied_objs++;
1285+
1286+
for (j = 0; j < count_props; j++) {
1287+
uint32_t prop_id;
1288+
uint64_t prop_value;
1289+
struct drm_property *prop;
1290+
1291+
if (get_user(prop_id, props_ptr + copied_props)) {
1292+
ret = -EFAULT;
1293+
goto fail;
1294+
}
1295+
1296+
prop = drm_property_find(dev, prop_id);
1297+
if (!prop) {
1298+
ret = -ENOENT;
1299+
goto fail;
1300+
}
1301+
1302+
if (get_user(prop_value, prop_values_ptr + copied_props)) {
1303+
ret = -EFAULT;
1304+
goto fail;
1305+
}
1306+
1307+
ret = atomic_set_prop(state, obj, prop, prop_value);
1308+
if (ret)
1309+
goto fail;
1310+
1311+
copied_props++;
1312+
}
1313+
}
1314+
1315+
if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
1316+
int ncrtcs = dev->mode_config.num_crtc;
1317+
1318+
for (i = 0; i < ncrtcs; i++) {
1319+
struct drm_crtc_state *crtc_state = state->crtc_states[i];
1320+
struct drm_pending_vblank_event *e;
1321+
1322+
if (!crtc_state)
1323+
continue;
1324+
1325+
e = create_vblank_event(dev, file_priv, arg->user_data);
1326+
if (!e) {
1327+
ret = -ENOMEM;
1328+
goto fail;
1329+
}
1330+
1331+
crtc_state->event = e;
1332+
}
1333+
}
1334+
1335+
if (arg->flags & DRM_MODE_ATOMIC_TEST_ONLY) {
1336+
ret = drm_atomic_check_only(state);
1337+
/* _check_only() does not free state, unlike _commit() */
1338+
drm_atomic_state_free(state);
1339+
} else if (arg->flags & DRM_MODE_ATOMIC_NONBLOCK) {
1340+
ret = drm_atomic_async_commit(state);
1341+
} else {
1342+
ret = drm_atomic_commit(state);
1343+
}
1344+
1345+
/* if succeeded, fixup legacy plane crtc/fb ptrs before dropping
1346+
* locks (ie. while it is still safe to deref plane->state). We
1347+
* need to do this here because the driver entry points cannot
1348+
* distinguish between legacy and atomic ioctls.
1349+
*/
1350+
drm_for_each_plane_mask(plane, dev, plane_mask) {
1351+
if (ret == 0) {
1352+
struct drm_framebuffer *new_fb = plane->state->fb;
1353+
if (new_fb)
1354+
drm_framebuffer_reference(new_fb);
1355+
plane->fb = new_fb;
1356+
plane->crtc = plane->state->crtc;
1357+
} else {
1358+
plane->old_fb = NULL;
1359+
}
1360+
if (plane->old_fb) {
1361+
drm_framebuffer_unreference(plane->old_fb);
1362+
plane->old_fb = NULL;
1363+
}
1364+
}
1365+
1366+
drm_modeset_drop_locks(&ctx);
1367+
drm_modeset_acquire_fini(&ctx);
1368+
1369+
return ret;
1370+
1371+
fail:
1372+
if (ret == -EDEADLK)
1373+
goto backoff;
1374+
1375+
if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
1376+
int ncrtcs = dev->mode_config.num_crtc;
1377+
1378+
for (i = 0; i < ncrtcs; i++) {
1379+
struct drm_crtc_state *crtc_state = state->crtc_states[i];
1380+
1381+
if (!crtc_state)
1382+
continue;
1383+
1384+
destroy_vblank_event(dev, file_priv, crtc_state->event);
1385+
crtc_state->event = NULL;
1386+
}
1387+
}
1388+
1389+
drm_atomic_state_free(state);
1390+
1391+
drm_modeset_drop_locks(&ctx);
1392+
drm_modeset_acquire_fini(&ctx);
1393+
1394+
return ret;
1395+
1396+
backoff:
1397+
drm_atomic_state_clear(state);
1398+
drm_modeset_backoff(&ctx);
1399+
1400+
goto retry;
1401+
}

‎drivers/gpu/drm/drm_crtc.c

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -4303,7 +4303,7 @@ EXPORT_SYMBOL(drm_mode_connector_update_edid_property);
43034303
* object to which the property is attached has a chance to take it's own
43044304
* reference).
43054305
*/
4306-
static bool drm_property_change_valid_get(struct drm_property *property,
4306+
bool drm_property_change_valid_get(struct drm_property *property,
43074307
uint64_t value, struct drm_mode_object **ref)
43084308
{
43094309
int i;
@@ -4365,7 +4365,7 @@ static bool drm_property_change_valid_get(struct drm_property *property,
43654365
return false;
43664366
}
43674367

4368-
static void drm_property_change_valid_put(struct drm_property *property,
4368+
void drm_property_change_valid_put(struct drm_property *property,
43694369
struct drm_mode_object *ref)
43704370
{
43714371
if (!ref)

‎drivers/gpu/drm/drm_ioctl.c

Lines changed: 1 addition & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -630,6 +630,7 @@ static const struct drm_ioctl_desc drm_ioctls[] = {
630630
DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
631631
DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
632632
DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR2, drm_mode_cursor2_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
633+
DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATOMIC, drm_mode_atomic_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
633634
};
634635

635636
#define DRM_CORE_IOCTL_COUNT ARRAY_SIZE( drm_ioctls )

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