Call zeInitDrivers in L0 provider

According to the L0 spec, zeInitDrivers must be called
(by every library) before calling any other APIs.

Not calling zeInitDrivers causes crash when using
statically linked L0 loader in UR.

Author: igchor

src/provider/provider_level_zero.c

@@ -14,6 +14,7 @@
 #include <umf/memory_provider_ops.h>
 #include <umf/providers/provider_level_zero.h>
 
+#include "base_alloc_global.h"
 #include "provider_level_zero_internal.h"
 #include "utils_load_library.h"
 #include "utils_log.h"
@@ -111,7 +112,6 @@ umf_memory_provider_ops_t *umfLevelZeroMemoryProviderOps(void) {
 
 #else // !defined(UMF_NO_LEVEL_ZERO_PROVIDER)
 
-#include "base_alloc_global.h"
 #include "libumf.h"
 #include "utils_assert.h"
 #include "utils_common.h"
@@ -211,6 +211,49 @@ static umf_result_t ze2umf_result(ze_result_t result) {
     }
 }
 
+static umf_result_t ze_init_drivers(void *lib_handle, const char *lib_name) {
+    ze_result_t (*zeInitDriversFunc)(uint32_t *, ze_driver_handle_t *,
+                                     ze_init_driver_type_desc_t *);
+    *(void **)&zeInitDriversFunc =
+        utils_get_symbol_addr(lib_handle, "zeInitDrivers", lib_name);
+    if (!zeInitDriversFunc) {
+        return UMF_RESULT_ERROR_DEPENDENCY_UNAVAILABLE;
+    }
+
+    ze_init_driver_type_desc_t desc = {
+        .stype = ZE_STRUCTURE_TYPE_INIT_DRIVER_TYPE_DESC,
+        .pNext = NULL,
+        .flags = ZE_INIT_DRIVER_TYPE_FLAG_GPU};
+    uint32_t driverCount = 0;
+    ze_result_t result = zeInitDriversFunc(&driverCount, NULL, &desc);
+    if (result != ZE_RESULT_SUCCESS) {
+        return ze2umf_result(result);
+    }
+
+    ze_driver_handle_t *zeAllDrivers =
+        umf_ba_global_alloc(sizeof(ze_driver_handle_t) * driverCount);
+    result = zeInitDriversFunc(&driverCount, zeAllDrivers, &desc);
+    umf_ba_global_free(zeAllDrivers);
+    if (result != ZE_RESULT_SUCCESS) {
+        return ze2umf_result(result);
+    }
+
+    return UMF_RESULT_SUCCESS;
+}
+
+static umf_result_t ze_init(void *lib_handle, const char *lib_name) {
+    ze_result_t (*zeInitFunc)(ze_init_flag_t);
+    *(void **)&zeInitFunc =
+        utils_get_symbol_addr(lib_handle, "zeInit", lib_name);
+
+    if (!zeInitFunc) {
+        return UMF_RESULT_ERROR_DEPENDENCY_UNAVAILABLE;
+    }
+
+    ze_result_t result = zeInitFunc(ZE_INIT_FLAG_GPU_ONLY);
+    return ze2umf_result(result);
+}
+
 static void init_ze_global_state(void) {
 #ifdef _WIN32
     const char *lib_name = "ze_loader.dll";
@@ -266,6 +309,19 @@ static void init_ze_global_state(void) {
         utils_close_library(lib_handle);
         return;
     }
+
+    if (ze_init_drivers(lib_handle, lib_name) != UMF_RESULT_SUCCESS) {
+        LOG_INFO("Initializing Level Zero through zeInitDrivers failed. "
+                 "Falling back to zeInit.");
+
+        if (ze_init(lib_handle, lib_name) != UMF_RESULT_SUCCESS) {
+            LOG_FATAL("Failed to initialize Level Zero");
+            Init_ze_global_state_failed = true;
+            utils_close_library(lib_handle);
+            return;
+        }
+    }
+
     ze_lib_handle = lib_handle;
 }