/* * Copyright 2017, Data61 * Commonwealth Scientific and Industrial Research Organisation (CSIRO) * ABN 41 687 119 230. * * This software may be distributed and modified according to the terms of * the BSD 2-Clause license. Note that NO WARRANTY is provided. * See "LICENSE_BSD2.txt" for details. * * @TAG(DATA61_BSD) */ #include #include #include #include #include #include #include #include #include #include #include "serial_server.h" #include seL4_Error serial_server_parent_spawn_thread(simple_t *parent_simple, vka_t *parent_vka, vspace_t *parent_vspace, uint8_t priority) { const size_t shmem_max_size = SERIAL_SERVER_SHMEM_MAX_SIZE; seL4_Error error; size_t shmem_max_n_pages; cspacepath_t parent_cspace_cspath; seL4_MessageInfo_t tag; if (parent_simple == NULL || parent_vka == NULL || parent_vspace == NULL) { return seL4_InvalidArgument; } memset(get_serial_server(), 0, sizeof(serial_server_context_t)); /* Get a CPtr to the parent's root cnode. */ shmem_max_n_pages = BYTES_TO_4K_PAGES(shmem_max_size); vka_cspace_make_path(parent_vka, 0, &parent_cspace_cspath); get_serial_server()->server_vka = parent_vka; get_serial_server()->server_vspace = parent_vspace; get_serial_server()->server_cspace = parent_cspace_cspath.root; get_serial_server()->server_simple = parent_simple; /* Allocate the Endpoint that the server will be listening on. */ error = vka_alloc_endpoint(parent_vka, &get_serial_server()->server_ep_obj); if (error != 0) { ZF_LOGE(SERSERVP"spawn_thread: failed to alloc endpoint, err=%d.", error); return error; } /* And also allocate a badged copy of the Server's endpoint that the Parent * can use to send to the Server. This is used to allow the Server to report * back to the Parent on whether or not the Server successfully bound to a * platform serial driver. * * This badged endpoint will be reused by the library as the Parent's badged * Endpoint cap, if the Parent itself ever chooses to connect() to the * Server later on. */ get_serial_server()->parent_badge_value = serial_server_badge_value_alloc(); if (get_serial_server()->parent_badge_value == SERIAL_SERVER_BADGE_VALUE_EMPTY) { error = seL4_NotEnoughMemory; goto out; } error = vka_mint_object(parent_vka, &get_serial_server()->server_ep_obj, &get_serial_server()->_badged_server_ep_cspath, seL4_AllRights, get_serial_server()->parent_badge_value); if (error != 0) { ZF_LOGE(SERSERVP"spawn_thread: Failed to mint badged Endpoint cap to " "server.\n" "\tParent cannot confirm Server thread successfully spawned."); goto out; } /* Allocate enough Cnode slots in our CSpace to enable us to receive * frame caps from our clients, sufficient to cover "shmem_max_size". * The problem here is that we're sort of forced to assume that we get * these slots contiguously. If they're not, we have a problem. * * If a client tries to send us too many frames, we respond with an error, * and indicate our shmem_max_size in the SSMSGREG_RESPONSE * message register. */ get_serial_server()->frame_cap_recv_cspaths = calloc(shmem_max_n_pages, sizeof(cspacepath_t)); if (get_serial_server()->frame_cap_recv_cspaths == NULL) { error = seL4_NotEnoughMemory; goto out; } for (size_t i = 0; i < shmem_max_n_pages; i++) { error = vka_cspace_alloc_path(parent_vka, &get_serial_server()->frame_cap_recv_cspaths[i]); if (error != 0) { ZF_LOGE(SERSERVP"spawn_thread: Failed to alloc enough cnode slots " "to receive shmem frame caps equal to %zd bytes.", shmem_max_size); goto out; } } sel4utils_thread_config_t config = thread_config_default(parent_simple, parent_cspace_cspath.root, seL4_NilData, get_serial_server()->server_ep_obj.cptr, priority); error = sel4utils_configure_thread_config(parent_vka, parent_vspace, parent_vspace, config, &get_serial_server()->server_thread); if (error != 0) { ZF_LOGE(SERSERVP"spawn_thread: sel4utils_configure_thread failed " "with %d.", error); goto out; } NAME_THREAD(get_serial_server()->server_thread.tcb.cptr, "serial server"); error = sel4utils_start_thread(&get_serial_server()->server_thread, (sel4utils_thread_entry_fn)&serial_server_main, NULL, NULL, 1); if (error != 0) { ZF_LOGE(SERSERVP"spawn_thread: sel4utils_start_thread failed with " "%d.", error); goto out; } /* When the Server is spawned, it will reply to tell us whether or not it * successfully bound itself to the platform serial device. Block here * and wait for that reply. */ seL4_SetMR(SSMSGREG_FUNC, FUNC_SERVER_SPAWN_SYNC_REQ); tag = seL4_MessageInfo_new(0, 0, 0, SSMSGREG_SPAWN_SYNC_REQ_END); tag = seL4_Call(get_serial_server()->_badged_server_ep_cspath.capPtr, tag); /* Did all go well with the server? */ if (seL4_GetMR(SSMSGREG_FUNC) != FUNC_SERVER_SPAWN_SYNC_ACK) { ZF_LOGE(SERSERVP"spawn_thread: Server thread sync message after spawn " "was not a SYNC_ACK as expected."); error = seL4_InvalidArgument; goto out; } error = seL4_MessageInfo_get_label(tag); if (error != 0) { ZF_LOGE(SERSERVP"spawn_thread: Server thread failed to bind to the " "platform serial device."); goto out; } get_serial_server()->shmem_max_size = shmem_max_size; get_serial_server()->shmem_max_n_pages = shmem_max_n_pages; return 0; out: if (get_serial_server()->frame_cap_recv_cspaths != NULL) { for (size_t i = 0; i < shmem_max_n_pages; i++) { /* Since the array was allocated with calloc(), it was zero'd out. So * those indexes that didn't get allocated will have NULL in them. * Break early on the first index that has NULL. */ if (get_serial_server()->frame_cap_recv_cspaths[i].capPtr == 0) { break; } vka_cspace_free_path(parent_vka, get_serial_server()->frame_cap_recv_cspaths[i]); } } free(get_serial_server()->frame_cap_recv_cspaths); if (get_serial_server()->_badged_server_ep_cspath.capPtr != 0) { vka_cspace_free_path(parent_vka, get_serial_server()->_badged_server_ep_cspath); } if (get_serial_server()->parent_badge_value != SERIAL_SERVER_BADGE_VALUE_EMPTY) { serial_server_badge_value_free(get_serial_server()->parent_badge_value); } vka_free_object(parent_vka, &get_serial_server()->server_ep_obj); return error; } int serial_server_parent_vka_mint_endpoint(vka_t *client_vka, cspacepath_t *badged_server_ep_cspath) { if (client_vka == NULL || badged_server_ep_cspath == NULL) { return seL4_InvalidArgument; } seL4_Word new_badge_value = serial_server_badge_value_alloc(); if (new_badge_value == SERIAL_SERVER_BADGE_VALUE_EMPTY) { return -1; } /* Mint the Endpoint to a new client. */ return vka_mint_object_inter_cspace(get_serial_server()->server_vka, &get_serial_server()->server_ep_obj, client_vka, badged_server_ep_cspath, seL4_AllRights, new_badge_value); } static inline void parent_ep_obj_to_cspath(cspacepath_t *result) { if (result == NULL) { return; } vka_cspace_make_path(get_serial_server()->server_vka, get_serial_server()->server_ep_obj.cptr, result); } int serial_server_allocate_client_badged_ep(cspacepath_t dest_slot) { cspacepath_t server_ep_cspath; seL4_Word new_badge_value = serial_server_badge_value_alloc(); if (new_badge_value == SERIAL_SERVER_BADGE_VALUE_EMPTY) { return -1; } parent_ep_obj_to_cspath(&server_ep_cspath); return vka_cnode_mint(&dest_slot, &server_ep_cspath, seL4_AllRights, new_badge_value); } seL4_CPtr serial_server_parent_mint_endpoint_to_process(sel4utils_process_t *p) { if (p == NULL) { return 0; } cspacepath_t server_ep_cspath; seL4_Word new_badge_value = serial_server_badge_value_alloc(); if (new_badge_value == SERIAL_SERVER_BADGE_VALUE_EMPTY) { return -1; } parent_ep_obj_to_cspath(&server_ep_cspath); return sel4utils_mint_cap_to_process(p, server_ep_cspath, seL4_AllRights, new_badge_value); }