iris: Add vm bind and unbind to kmd backend

At this time this is a nop for i915 but in future we will have a
Xe implementation.

Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/22059>

src/gallium/drivers/iris/i915/iris_kmd_backend.c

@@ -358,6 +358,22 @@ i915_batch_submit(struct iris_batch *batch)
    return ret;
 }
 
+static bool
+i915_gem_vm_bind(struct iris_bo *bo)
+{
+   /*
+    * i915 does not support VM_BIND yet. The binding operation happens at
+    * submission when we supply BO handle & offset in the execbuffer list.
+    */
+   return true;
+}
+
+static bool
+i915_gem_vm_unbind(struct iris_bo *bo)
+{
+   return true;
+}
+
 const struct iris_kmd_backend *i915_get_backend(void)
 {
    static const struct iris_kmd_backend i915_backend = {
@@ -367,6 +383,8 @@ const struct iris_kmd_backend *i915_get_backend(void)
       .gem_mmap = i915_gem_mmap,
       .batch_check_for_reset = i915_batch_check_for_reset,
       .batch_submit = i915_batch_submit,
+      .gem_vm_bind = i915_gem_vm_bind,
+      .gem_vm_unbind = i915_gem_vm_unbind,
    };
    return &i915_backend;
 }

src/gallium/drivers/iris/iris_bufmgr.c

@@ -931,6 +931,12 @@ alloc_bo_from_cache(struct iris_bufmgr *bufmgr,
        */
       if (memzone != iris_memzone_for_address(cur->address) ||
           cur->address % alignment != 0) {
+         if (!bufmgr->kmd_backend->gem_vm_unbind(cur)) {
+            DBG("Unable to unbind vm of buf %u\n", cur->gem_handle);
+            bo_free(cur);
+            continue;
+         }
+
          vma_free(bufmgr, cur->address, cur->size);
          cur->address = 0ull;
       }
@@ -1101,6 +1107,9 @@ iris_bo_alloc(struct iris_bufmgr *bufmgr,
 
       if (bo->address == 0ull)
          goto err_free;
+
+      if (!bufmgr->kmd_backend->gem_vm_bind(bo))
+         goto err_vm_alloc;
    }
 
    bo->name = name;
@@ -1136,6 +1145,8 @@ iris_bo_alloc(struct iris_bufmgr *bufmgr,
 
    return bo;
 
+err_vm_alloc:
+   vma_free(bufmgr, bo->address, bo->size);
 err_free:
    simple_mtx_lock(&bufmgr->lock);
    bo_free(bo);
@@ -1266,6 +1277,9 @@ iris_bo_gem_create_from_name(struct iris_bufmgr *bufmgr,
    if (bo->address == 0ull)
       goto err_free;
 
+   if (!bufmgr->kmd_backend->gem_vm_bind(bo))
+      goto err_vm_alloc;
+
    _mesa_hash_table_insert(bufmgr->handle_table, &bo->gem_handle, bo);
    _mesa_hash_table_insert(bufmgr->name_table, &bo->real.global_name, bo);
 
@@ -1275,6 +1289,8 @@ out:
    simple_mtx_unlock(&bufmgr->lock);
    return bo;
 
+err_vm_alloc:
+   vma_free(bufmgr, bo->address, bo->size);
 err_free:
    bo_free(bo);
    simple_mtx_unlock(&bufmgr->lock);
@@ -1312,6 +1328,12 @@ bo_close(struct iris_bo *bo)
       assert(list_is_empty(&bo->real.exports));
    }
 
+   /* Unbind and return the VMA for reuse */
+   if (bufmgr->kmd_backend->gem_vm_unbind(bo))
+      vma_free(bo->bufmgr, bo->address, bo->size);
+   else
+      DBG("Unable to unbind vm of buf %u\n", bo->gem_handle);
+
    /* Close this object */
    struct drm_gem_close close = { .handle = bo->gem_handle };
    int ret = intel_ioctl(bufmgr->fd, DRM_IOCTL_GEM_CLOSE, &close);
@@ -1325,9 +1347,6 @@ bo_close(struct iris_bo *bo)
                                 bo->size);
    }
 
-   /* Return the VMA for reuse */
-   vma_free(bo->bufmgr, bo->address, bo->size);
-
    for (int d = 0; d < bo->deps_size; d++) {
       for (int b = 0; b < IRIS_BATCH_COUNT; b++) {
          iris_syncobj_reference(bufmgr, &bo->deps[d].write_syncobjs[b], NULL);
@@ -1824,12 +1843,17 @@ iris_bo_import_dmabuf(struct iris_bufmgr *bufmgr, int prime_fd)
    if (bo->address == 0ull)
       goto err_free;
 
+   if (!bufmgr->kmd_backend->gem_vm_bind(bo))
+      goto err_vm_alloc;
+
    _mesa_hash_table_insert(bufmgr->handle_table, &bo->gem_handle, bo);
 
 out:
    simple_mtx_unlock(&bufmgr->lock);
    return bo;
 
+err_vm_alloc:
+   vma_free(bufmgr, bo->address, bo->size);
 err_free:
    bo_free(bo);
    simple_mtx_unlock(&bufmgr->lock);
@@ -2065,6 +2089,9 @@ intel_aux_map_buffer_alloc(void *driver_ctx, uint32_t size)
    if (bo->address == 0ull)
       goto err_free;
 
+   if (!bufmgr->kmd_backend->gem_vm_bind(bo))
+      goto err_vm_alloc;
+
    simple_mtx_unlock(&bufmgr->lock);
 
    bo->name = "aux-map";
@@ -2081,6 +2108,8 @@ intel_aux_map_buffer_alloc(void *driver_ctx, uint32_t size)
    buf->map = iris_bo_map(NULL, bo, MAP_WRITE | MAP_RAW);
    return buf;
 
+err_vm_alloc:
+   vma_free(bufmgr, bo->address, bo->size);
 err_free:
    free(buf);
    bo_free(bo);

src/gallium/drivers/iris/iris_kmd_backend.h

@@ -44,6 +44,8 @@ struct iris_kmd_backend {
    void *(*gem_mmap)(struct iris_bufmgr *bufmgr, struct iris_bo *bo);
    enum pipe_reset_status (*batch_check_for_reset)(struct iris_batch *batch);
    int (*batch_submit)(struct iris_batch *batch);
+   bool (*gem_vm_bind)(struct iris_bo *bo);
+   bool (*gem_vm_unbind)(struct iris_bo *bo);
 };
 
 const struct iris_kmd_backend *