X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavutil%2Fhwcontext_drm.c;h=7a9fdbd263d48c5817c15ad34fee6775a5e27838;hb=cb9dbc60db1847fcb594684b92334da54ea8757e;hp=32cbde82ebfae6b2f3780a1caf0594f19cc964d0;hpb=fda424b300c1a0b991296aa585691609d01196bd;p=ffmpeg

diff --git a/libavutil/hwcontext_drm.c b/libavutil/hwcontext_drm.c
index 32cbde82ebf..7a9fdbd263d 100644
--- a/libavutil/hwcontext_drm.c
+++ b/libavutil/hwcontext_drm.c
@@ -16,10 +16,20 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
+#include "config.h"
+
 #include <fcntl.h>
 #include <sys/mman.h>
 #include <unistd.h>
 
+/* This was introduced in version 4.6. And may not exist all without an
+ * optional package. So to prevent a hard dependency on needing the Linux
+ * kernel headers to compile, make this optional. */
+#if HAVE_LINUX_DMA_BUF_H
+#include <linux/dma-buf.h>
+#include <sys/ioctl.h>
+#endif
+
 #include <drm.h>
 #include <xf86drm.h>
 
@@ -85,6 +95,8 @@ static int drm_get_buffer(AVHWFramesContext *hwfc, AVFrame *frame)
 typedef struct DRMMapping {
     // Address and length of each mmap()ed region.
     int nb_regions;
+    int sync_flags;
+    int object[AV_DRM_MAX_PLANES];
     void *address[AV_DRM_MAX_PLANES];
     size_t length[AV_DRM_MAX_PLANES];
 } DRMMapping;
@@ -93,10 +105,14 @@ static void drm_unmap_frame(AVHWFramesContext *hwfc,
                             HWMapDescriptor *hwmap)
 {
     DRMMapping *map = hwmap->priv;
-    int i;
 
-    for (i = 0; i < map->nb_regions; i++)
+    for (int i = 0; i < map->nb_regions; i++) {
+#if HAVE_LINUX_DMA_BUF_H
+        struct dma_buf_sync sync = { .flags = DMA_BUF_SYNC_END | map->sync_flags };
+        ioctl(map->object[i], DMA_BUF_IOCTL_SYNC, &sync);
+#endif
         munmap(map->address[i], map->length[i]);
+    }
 
     av_free(map);
 }
@@ -105,6 +121,9 @@ static int drm_map_frame(AVHWFramesContext *hwfc,
                          AVFrame *dst, const AVFrame *src, int flags)
 {
     const AVDRMFrameDescriptor *desc = (AVDRMFrameDescriptor*)src->data[0];
+#if HAVE_LINUX_DMA_BUF_H
+    struct dma_buf_sync sync_start = { 0 };
+#endif
     DRMMapping *map;
     int err, i, p, plane;
     int mmap_prot;
@@ -120,6 +139,14 @@ static int drm_map_frame(AVHWFramesContext *hwfc,
     if (flags & AV_HWFRAME_MAP_WRITE)
         mmap_prot |= PROT_WRITE;
 
+#if HAVE_LINUX_DMA_BUF_H
+    if (flags & AV_HWFRAME_MAP_READ)
+        map->sync_flags |= DMA_BUF_SYNC_READ;
+    if (flags & AV_HWFRAME_MAP_WRITE)
+        map->sync_flags |= DMA_BUF_SYNC_WRITE;
+    sync_start.flags = DMA_BUF_SYNC_START | map->sync_flags;
+#endif
+
     av_assert0(desc->nb_objects <= AV_DRM_MAX_PLANES);
     for (i = 0; i < desc->nb_objects; i++) {
         addr = mmap(NULL, desc->objects[i].size, mmap_prot, MAP_SHARED,
@@ -133,6 +160,13 @@ static int drm_map_frame(AVHWFramesContext *hwfc,
 
         map->address[i] = addr;
         map->length[i]  = desc->objects[i].size;
+        map->object[i] = desc->objects[i].fd;
+
+#if HAVE_LINUX_DMA_BUF_H
+        /* We're not checking for errors here because the kernel may not
+         * support the ioctl, in which case its okay to carry on */
+        ioctl(desc->objects[i].fd, DMA_BUF_IOCTL_SYNC, &sync_start);
+#endif
     }
     map->nb_regions = i;