freedreno/drm: Rework bo creation path

Decoupling handle and fd_bo creation simplifies things for "normal" drm
drivers, avoiding duplication for the create vs import paths.  But this
is awkward for the virtio backend when wants to do multiple things in
the same guest<->host round trip.

So instead, split the paths in the interface backend and move the code
sharing for the two different paths into the msm backend itself.

Signed-off-by: Rob Clark <robdclark@chromium.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/14900>

src/freedreno/drm/freedreno_bo.c

@@ -57,6 +57,21 @@ lookup_bo(struct hash_table *tbl, uint32_t key)
    return bo;
 }
 
+static void
+bo_init_common(struct fd_bo *bo, struct fd_device *dev)
+{
+   /* Backend should have initialized these: */
+   assert(bo->size);
+   assert(bo->handle);
+
+   bo->dev = dev;
+   bo->iova = bo->funcs->iova(bo);
+   bo->reloc_flags = FD_RELOC_FLAGS_INIT;
+
+   p_atomic_set(&bo->refcnt, 1);
+   list_inithead(&bo->list);
+}
+
 /* allocate a new buffer object, call w/ table_lock held */
 static struct fd_bo *
 bo_from_handle(struct fd_device *dev, uint32_t size, uint32_t handle)
@@ -73,16 +88,12 @@ bo_from_handle(struct fd_device *dev, uint32_t size, uint32_t handle)
       drmIoctl(dev->fd, DRM_IOCTL_GEM_CLOSE, &req);
       return NULL;
    }
-   bo->dev = dev;
-   bo->size = size;
-   bo->handle = handle;
-   bo->iova = bo->funcs->iova(bo);
-   bo->reloc_flags = FD_RELOC_FLAGS_INIT;
 
-   p_atomic_set(&bo->refcnt, 1);
-   list_inithead(&bo->list);
+   bo_init_common(bo, dev);
+
    /* add ourself into the handle table: */
    _mesa_hash_table_insert(dev->handle_table, &bo->handle, bo);
+
    return bo;
 }
 
@@ -91,8 +102,6 @@ bo_new(struct fd_device *dev, uint32_t size, uint32_t flags,
        struct fd_bo_cache *cache)
 {
    struct fd_bo *bo = NULL;
-   uint32_t handle;
-   int ret;
 
    /* demote cached-coherent to WC if not supported: */
    if ((flags & FD_BO_CACHED_COHERENT) && !dev->has_cached_coherent)
@@ -102,12 +111,15 @@ bo_new(struct fd_device *dev, uint32_t size, uint32_t flags,
    if (bo)
       return bo;
 
-   ret = dev->funcs->bo_new_handle(dev, size, flags, &handle);
-   if (ret)
+   bo = dev->funcs->bo_new(dev, size, flags);
+   if (!bo)
       return NULL;
 
+   bo_init_common(bo, dev);
+
    simple_mtx_lock(&table_lock);
-   bo = bo_from_handle(dev, size, handle);
+   /* add ourself into the handle table: */
+   _mesa_hash_table_insert(dev->handle_table, &bo->handle, bo);
    simple_mtx_unlock(&table_lock);
 
    bo->alloc_flags = flags;

src/freedreno/drm/freedreno_priv.h

@@ -89,10 +89,16 @@ grow(void **ptr, uint16_t nr, uint16_t *max, uint16_t sz)
 
 
 struct fd_device_funcs {
-   int (*bo_new_handle)(struct fd_device *dev, uint32_t size, uint32_t flags,
-                        uint32_t *handle);
+   /* Create a new buffer object:
+    */
+   struct fd_bo *(*bo_new)(struct fd_device *dev, uint32_t size, uint32_t flags);
+
+   /* Create a new buffer object from existing handle (ie. dma-buf or
+    * flink import):
+    */
    struct fd_bo *(*bo_from_handle)(struct fd_device *dev, uint32_t size,
                                    uint32_t handle);
+
    struct fd_pipe *(*pipe_new)(struct fd_device *dev, enum fd_pipe_id id,
                                unsigned prio);
    void (*destroy)(struct fd_device *dev);

src/freedreno/drm/msm/msm_bo.c

@@ -164,9 +164,8 @@ static const struct fd_bo_funcs funcs = {
 };
 
 /* allocate a buffer handle: */
-int
-msm_bo_new_handle(struct fd_device *dev, uint32_t size, uint32_t flags,
-                  uint32_t *handle)
+static int
+new_handle(struct fd_device *dev, uint32_t size, uint32_t flags, uint32_t *handle)
 {
    struct drm_msm_gem_new req = {
       .size = size,
@@ -195,6 +194,20 @@ msm_bo_new_handle(struct fd_device *dev, uint32_t size, uint32_t flags,
 
 /* allocate a new buffer object */
 struct fd_bo *
+msm_bo_new(struct fd_device *dev, uint32_t size, uint32_t flags)
+{
+   uint32_t handle;
+   int ret;
+
+   ret = new_handle(dev, size, flags, &handle);
+   if (ret)
+      return NULL;
+
+   return msm_bo_from_handle(dev, size, handle);
+}
+
+/* allocate a new buffer object from existing handle (import) */
+struct fd_bo *
 msm_bo_from_handle(struct fd_device *dev, uint32_t size, uint32_t handle)
 {
    struct msm_bo *msm_bo;
@@ -205,6 +218,8 @@ msm_bo_from_handle(struct fd_device *dev, uint32_t size, uint32_t handle)
       return NULL;
 
    bo = &msm_bo->base;
+   bo->size = size;
+   bo->handle = handle;
    bo->funcs = &funcs;
 
    return bo;

src/freedreno/drm/msm/msm_device.c

@@ -41,7 +41,7 @@ msm_device_destroy(struct fd_device *dev)
 }
 
 static const struct fd_device_funcs funcs = {
-   .bo_new_handle = msm_bo_new_handle,
+   .bo_new = msm_bo_new,
    .bo_from_handle = msm_bo_from_handle,
    .pipe_new = msm_pipe_new,
    .destroy = msm_device_destroy,

src/freedreno/drm/msm/msm_priv.h

@@ -96,8 +96,7 @@ struct msm_bo {
 };
 FD_DEFINE_CAST(fd_bo, msm_bo);
 
-int msm_bo_new_handle(struct fd_device *dev, uint32_t size, uint32_t flags,
-                      uint32_t *handle);
+struct fd_bo *msm_bo_new(struct fd_device *dev, uint32_t size, uint32_t flags);
 struct fd_bo *msm_bo_from_handle(struct fd_device *dev, uint32_t size,
                                  uint32_t handle);