libliftoff/device.c
Simon Ser f6b4cd6197
Retry atomic commit on EINTR and EAGAIN
From the kernel docs:

> -EINTR, -EAGAIN or -ERESTARTSYS, if the IOCTL should be restarted. This can
> either be due to a pending signal, or because the driver needs to completely
> bail out to recover from an exceptional situation like a GPU hang. From a
> userspace point of view all errors are treated equally.

We're not handling ERESTARTSYS because it's non-POSIX.
2020-01-13 12:28:39 +01:00

106 lines
2.4 KiB
C

#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "log.h"
#include "private.h"
struct liftoff_device *liftoff_device_create(int drm_fd)
{
struct liftoff_device *device;
drmModeRes *drm_res;
drmModePlaneRes *drm_plane_res;
uint32_t i;
device = calloc(1, sizeof(*device));
if (device == NULL) {
liftoff_log_errno(LIFTOFF_ERROR, "calloc");
return NULL;
}
liftoff_list_init(&device->planes);
liftoff_list_init(&device->outputs);
device->drm_fd = dup(drm_fd);
if (device->drm_fd < 0) {
liftoff_log_errno(LIFTOFF_ERROR, "dup");
liftoff_device_destroy(device);
return NULL;
}
drm_res = drmModeGetResources(drm_fd);
if (drm_res == NULL) {
liftoff_log_errno(LIFTOFF_ERROR, "drmModeGetResources");
liftoff_device_destroy(device);
return NULL;
}
device->crtcs = malloc(drm_res->count_crtcs * sizeof(uint32_t));
if (device->crtcs == NULL) {
liftoff_log_errno(LIFTOFF_ERROR, "malloc");
drmModeFreeResources(drm_res);
liftoff_device_destroy(device);
return NULL;
}
device->crtcs_len = drm_res->count_crtcs;
memcpy(device->crtcs, drm_res->crtcs,
drm_res->count_crtcs * sizeof(uint32_t));
drmModeFreeResources(drm_res);
/* TODO: allow users to choose which layers to hand over */
drm_plane_res = drmModeGetPlaneResources(drm_fd);
if (drm_plane_res == NULL) {
liftoff_log_errno(LIFTOFF_ERROR, "drmModeGetPlaneResources");
liftoff_device_destroy(device);
return NULL;
}
for (i = 0; i < drm_plane_res->count_planes; i++) {
if (plane_create(device, drm_plane_res->planes[i]) == NULL) {
liftoff_device_destroy(device);
return NULL;
}
}
drmModeFreePlaneResources(drm_plane_res);
return device;
}
void liftoff_device_destroy(struct liftoff_device *device)
{
struct liftoff_plane *plane, *tmp;
if (device == NULL) {
return;
}
close(device->drm_fd);
liftoff_list_for_each_safe(plane, tmp, &device->planes, link) {
plane_destroy(plane);
}
free(device->crtcs);
free(device);
}
bool device_test_commit(struct liftoff_device *device,
drmModeAtomicReq *req, bool *compatible)
{
int ret;
do {
ret = drmModeAtomicCommit(device->drm_fd, req,
DRM_MODE_ATOMIC_TEST_ONLY, NULL);
} while (-ret == EINTR || -ret == EAGAIN);
if (ret == 0) {
*compatible = true;
} else if (-ret == EINVAL || -ret == ERANGE) {
*compatible = false;
} else {
liftoff_log_errno(LIFTOFF_ERROR, "drmModeAtomicCommit");
*compatible = false;
return false;
}
return true;
}