Add RPC longhaul paging

ggml/include/ggml-rpc.h

@@ -8,7 +8,7 @@ extern "C" {
 
 #define RPC_PROTO_MAJOR_VERSION    4
 #define RPC_PROTO_MINOR_VERSION    0
-#define RPC_PROTO_PATCH_VERSION    3
+#define RPC_PROTO_PATCH_VERSION    4
 
 #ifdef  __cplusplus
 static_assert(GGML_OP_COUNT == 101, "GGML_OP_COUNT has changed - update RPC_PROTO_PATCH_VERSION");
@@ -27,6 +27,49 @@ GGML_BACKEND_API void ggml_backend_rpc_get_device_memory(const char * endpoint,
 GGML_BACKEND_API void ggml_backend_rpc_start_server(const char * endpoint, const char * cache_dir,
                                                     size_t n_threads, size_t n_devices, ggml_backend_dev_t * devices);
 
+struct ggml_backend_rpc_longhaul_shard {
+    const char * name;
+    uint64_t size;
+    uint64_t metadata_size;
+    uint8_t metadata_sha256[32];
+};
+
+struct ggml_backend_rpc_longhaul_source {
+    struct ggml_tensor * tensor;
+    uint32_t shard;
+    uint64_t offset;
+    uint64_t expert_size;
+    int32_t layer;
+};
+
+struct ggml_backend_rpc_longhaul_params {
+    uint32_t n_layers;
+    uint32_t n_experts;
+    uint32_t n_slots;
+    size_t n_shards;
+    const struct ggml_backend_rpc_longhaul_shard * shards;
+    size_t n_sources;
+    const struct ggml_backend_rpc_longhaul_source * sources;
+};
+
+GGML_BACKEND_API bool ggml_backend_rpc_longhaul_register(
+        const struct ggml_backend_rpc_longhaul_params * params,
+        uint64_t * registration_id,
+        char * error,
+        size_t error_size);
+
+GGML_BACKEND_API void ggml_backend_rpc_longhaul_unregister(
+        struct ggml_tensor * tensor,
+        uint64_t registration_id);
+
+GGML_BACKEND_API void ggml_backend_rpc_start_server_with_options(
+        const char * endpoint,
+        const char * cache_dir,
+        const char * longhaul_root,
+        size_t n_threads,
+        size_t n_devices,
+        ggml_backend_dev_t * devices);
+
 GGML_BACKEND_API ggml_backend_reg_t ggml_backend_rpc_reg(void);
 GGML_BACKEND_API ggml_backend_reg_t ggml_backend_rpc_add_server(const char * endpoint);