drm-shim: don't create a memfd per BO

Running shader-db on big servers with many cores, we're running out of
file descriptors.

Use a single 4Gb memfd instead and allocate from it using a VMA.

v2: Align VMA allocation to 4096 (Eric)

Signed-off-by: Lionel Landwerlin <[email protected]>
Acked-by: Matt Turner <[email protected]>
Reviewed-by: Eric Anholt <[email protected]>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4594>

1 files changed, 8 insertions, 1 deletions

diff --git a/src/drm-shim/drm_shim.h b/src/drm-shim/drm_shim.h
index 4d359dd7f1a..cb3951afa82 100644
--- a/src/drm-shim/drm_shim.h
+++ b/src/drm-shim/drm_shim.h
@@ -25,6 +25,7 @@
 
 #include "util/macros.h"
 #include "util/hash_table.h"
+#include "util/vma.h"
 
 #include <xf86drm.h>
 
@@ -40,6 +41,12 @@ struct shim_device {
    /* Mapping from int fd to struct shim_fd *. */
    struct hash_table *fd_map;
 
+   mtx_t mem_lock;
+   /* Heap from which shim_bo are allocated */
+   struct util_vma_heap mem_heap;
+
+   int mem_fd;
+
    int (**driver_ioctls)(int fd, unsigned long request, void *arg);
    int driver_ioctl_count;
 
@@ -61,7 +68,7 @@ struct shim_fd {
 };
 
 struct shim_bo {
-   int fd;
+   uint64_t mem_addr;
    void *map;
    int refcount;
    uint32_t size;