virgl: add virgl_resource_export_fd

This is useful when we need an fd from a virgl_resource.

Signed-off-by: Chia-I Wu <olvaffe@gmail.com>
Reviewed-by: Gurchetan Singh <gurchetansingh@chromium.org>

src/virgl_resource.c

@@ -26,6 +26,7 @@
 
 #include <assert.h>
 #include <errno.h>
+#include <fcntl.h>
 #include <string.h>
 #include <unistd.h>
 
@@ -212,3 +213,24 @@ virgl_resource_detach_iov(struct virgl_resource *res)
    res->iov = NULL;
    res->iov_count = 0;
 }
+
+enum virgl_resource_fd_type
+virgl_resource_export_fd(struct virgl_resource *res, int *fd)
+{
+   if (res->fd_type != VIRGL_RESOURCE_FD_INVALID) {
+#ifdef F_DUPFD_CLOEXEC
+      *fd = fcntl(res->fd, F_DUPFD_CLOEXEC, 0);
+      if (*fd < 0)
+         *fd = dup(res->fd);
+#else
+      *fd = dup(res->fd);
+#endif
+      return *fd >= 0 ? res->fd_type : VIRGL_RESOURCE_FD_INVALID;
+   } else if (res->pipe_resource) {
+      return pipe_callbacks.export_fd(res->pipe_resource,
+                                      fd,
+                                      pipe_callbacks.data);
+   }
+
+   return VIRGL_RESOURCE_FD_INVALID;
+}

src/virgl_resource.h

@@ -69,6 +69,10 @@ struct virgl_resource_pipe_callbacks {
                       int iov_count,
                       void *data);
    void (*detach_iov)(struct pipe_resource *pres, void *data);
+
+   enum virgl_resource_fd_type (*export_fd)(struct pipe_resource *pres,
+                                            int *fd,
+                                            void *data);
 };
 
 int
@@ -112,4 +116,7 @@ virgl_resource_attach_iov(struct virgl_resource *res,
 void
 virgl_resource_detach_iov(struct virgl_resource *res);
 
+enum virgl_resource_fd_type
+virgl_resource_export_fd(struct virgl_resource *res, int *fd);
+
 #endif /* VIRGL_RESOURCE_H */

src/vrend_renderer.c

@@ -5862,6 +5862,24 @@ static void vrend_pipe_resource_detach_iov(struct pipe_resource *pres,
    res->num_iovs = 0;
 }
 
+static enum virgl_resource_fd_type vrend_pipe_resource_export_fd(UNUSED struct pipe_resource *pres,
+                                                                 UNUSED int *fd,
+                                                                 UNUSED void *data)
+{
+#ifdef ENABLE_MINIGBM_ALLOCATION
+   struct vrend_resource *res = (struct vrend_resource *)pres;
+
+   if (res->storage_bits & VREND_STORAGE_GBM_BUFFER) {
+      int ret = virgl_gbm_export_fd(gbm->device,
+                                    gbm_bo_get_handle(res->gbm_bo).u32, fd);
+      if (!ret)
+         return VIRGL_RESOURCE_FD_DMABUF;
+   }
+#endif
+
+   return VIRGL_RESOURCE_FD_INVALID;
+}
+
 static const struct virgl_resource_pipe_callbacks *
 vrend_renderer_get_pipe_callbacks(void)
 {
@@ -5869,6 +5887,7 @@ vrend_renderer_get_pipe_callbacks(void)
       .unref = vrend_pipe_resource_unref,
       .attach_iov = vrend_pipe_resource_attach_iov,
       .detach_iov = vrend_pipe_resource_detach_iov,
+      .export_fd = vrend_pipe_resource_export_fd,
    };
 
    return &callbacks;