// (c) 2010 Thomas Schoebel-Theuer / 1&1 Internet AG // Server brick (just for demonstration) //#define BRICK_DEBUGGING //#define MARS_DEBUGGING //#define IO_DEBUGGING #include #include #include #define _STRATEGY #include "mars.h" #include "mars_bio.h" #include "mars_aio.h" #include "mars_sio.h" ///////////////////////// own type definitions //////////////////////// #include "mars_server.h" #define NR_SOCKETS 3 static struct mars_socket server_socket[NR_SOCKETS] = {}; static struct task_struct *server_thread[NR_SOCKETS] = {}; atomic_t server_handler_count = ATOMIC_INIT(0); EXPORT_SYMBOL_GPL(server_handler_count); ///////////////////////// own helper functions //////////////////////// static int cb_thread(void *data) { struct server_brick *brick = data; struct mars_socket *sock = &brick->handler_socket; bool aborted = false; bool ok = mars_get_socket(sock); int status = -EINVAL; MARS_DBG("--------------- cb_thread starting on socket #%d, ok = %d\n", sock->s_debug_nr, ok); if (!ok) goto done; brick->cb_running = true; wake_up_interruptible(&brick->startup_event); while (!brick_thread_should_stop() || !list_empty(&brick->cb_read_list) || !list_empty(&brick->cb_write_list) || atomic_read(&brick->in_flight) > 0) { struct server_mref_aspect *mref_a; struct mref_object *mref; struct list_head *tmp; unsigned long flags; wait_event_interruptible_timeout( brick->cb_event, !list_empty(&brick->cb_read_list) || !list_empty(&brick->cb_write_list), 1 * HZ); traced_lock(&brick->cb_lock, flags); tmp = brick->cb_write_list.next; if (tmp == &brick->cb_write_list) { tmp = brick->cb_read_list.next; if (tmp == &brick->cb_read_list) { traced_unlock(&brick->cb_lock, flags); brick_msleep(1000 / HZ); continue; } } list_del_init(tmp); traced_unlock(&brick->cb_lock, flags); mref_a = container_of(tmp, struct server_mref_aspect, cb_head); mref = mref_a->object; status = -EINVAL; CHECK_PTR(mref, err); status = 0; if (!aborted) { down(&brick->socket_sem); status = mars_send_cb(sock, mref); up(&brick->socket_sem); } err: if (unlikely(status < 0) && !aborted) { aborted = true; MARS_WRN("cannot send response, status = %d\n", status); /* Just shutdown the socket and forget all pending * requests. * The _client_ is responsible for resending * any lost operations. */ mars_shutdown_socket(sock); } if (mref_a->do_put) { GENERIC_INPUT_CALL(brick->inputs[0], mref_put, mref); atomic_dec(&brick->in_flight); } else { mars_free_mref(mref); } } mars_shutdown_socket(sock); mars_put_socket(sock); done: MARS_DBG("---------- cb_thread terminating, status = %d\n", status); wake_up_interruptible(&brick->startup_event); return status; } static void server_endio(struct generic_callback *cb) { struct server_mref_aspect *mref_a; struct mref_object *mref; struct server_brick *brick; int rw; unsigned long flags; mref_a = cb->cb_private; CHECK_PTR(mref_a, err); mref = mref_a->object; CHECK_PTR(mref, err); brick = mref_a->brick; if (!brick) { MARS_WRN("late IO callback -- cannot do anything\n"); return; } rw = mref->ref_rw; traced_lock(&brick->cb_lock, flags); if (rw) { list_add_tail(&mref_a->cb_head, &brick->cb_write_list); } else { list_add_tail(&mref_a->cb_head, &brick->cb_read_list); } traced_unlock(&brick->cb_lock, flags); wake_up_interruptible(&brick->cb_event); return; err: MARS_FAT("cannot handle callback - giving up\n"); } static int server_io(struct server_brick *brick, struct mars_socket *sock, struct mars_cmd *cmd) { struct mref_object *mref; struct server_mref_aspect *mref_a; int amount; int status = -ENOTRECOVERABLE; if (!brick->cb_running || !brick->handler_running || !mars_socket_is_alive(sock)) goto done; mref = server_alloc_mref(brick); status = -ENOMEM; if (!mref) goto done; mref_a = server_mref_get_aspect(brick, mref); if (unlikely(!mref_a)) { mars_free_mref(mref); goto done; } status = mars_recv_mref(sock, mref, cmd); if (status < 0) { mars_free_mref(mref); goto done; } mref_a->brick = brick; SETUP_CALLBACK(mref, server_endio, mref_a); amount = 0; if (!mref->ref_cs_mode < 2) amount = (mref->ref_len - 1) / 1024 + 1; mars_limit_sleep(&server_limiter, amount); status = GENERIC_INPUT_CALL(brick->inputs[0], mref_get, mref); if (unlikely(status < 0)) { MARS_WRN("mref_get execution error = %d\n", status); SIMPLE_CALLBACK(mref, status); status = 0; // continue serving requests goto done; } mref_a->do_put = true; atomic_inc(&brick->in_flight); GENERIC_INPUT_CALL(brick->inputs[0], mref_io, mref); done: return status; } static void _clean_list(struct server_brick *brick, struct list_head *start) { for (;;) { struct server_mref_aspect *mref_a; struct mref_object *mref; struct list_head *tmp = start->next; if (tmp == start) break; list_del_init(tmp); mref_a = container_of(tmp, struct server_mref_aspect, cb_head); mref_a->brick = NULL; mref = mref_a->object; if (!mref) continue; if (mref_a->do_put) { GENERIC_INPUT_CALL(brick->inputs[0], mref_put, mref); atomic_dec(&brick->in_flight); } else { mars_free_mref(mref); } } } static int _set_server_sio_params(struct mars_brick *_brick, void *private) { struct sio_brick *sio_brick = (void*)_brick; if (_brick->type != (void*)_sio_brick_type) { MARS_ERR("bad brick type\n"); return -EINVAL; } sio_brick->o_direct = false; sio_brick->o_fdsync = false; MARS_INF("name = '%s' path = '%s'\n", _brick->brick_name, _brick->brick_path); return 1; } static int _set_server_aio_params(struct mars_brick *_brick, void *private) { struct aio_brick *aio_brick = (void*)_brick; if (_brick->type == (void*)_sio_brick_type) { return _set_server_sio_params(_brick, private); } if (_brick->type != (void*)_aio_brick_type) { MARS_ERR("bad brick type\n"); return -EINVAL; } aio_brick->o_creat = false; aio_brick->o_direct = false; aio_brick->o_fdsync = false; MARS_INF("name = '%s' path = '%s'\n", _brick->brick_name, _brick->brick_path); return 1; } static int _set_server_bio_params(struct mars_brick *_brick, void *private) { struct bio_brick *bio_brick; if (_brick->type == (void*)_aio_brick_type) { return _set_server_aio_params(_brick, private); } if (_brick->type == (void*)_sio_brick_type) { return _set_server_sio_params(_brick, private); } if (_brick->type != (void*)_bio_brick_type) { MARS_ERR("bad brick type\n"); return -EINVAL; } bio_brick = (void*)_brick; bio_brick->ra_pages = 0; bio_brick->do_noidle = true; bio_brick->do_sync = true; bio_brick->do_unplug = true; MARS_INF("name = '%s' path = '%s'\n", _brick->brick_name, _brick->brick_path); return 1; } static int dummy_worker(struct mars_global *global, struct mars_dent *dent, bool prepare, bool direction) { return 0; } static int handler_thread(void *data) { struct server_brick *brick = data; struct mars_socket *sock = &brick->handler_socket; bool ok = mars_get_socket(sock); int debug_nr; int status = -EINVAL; MARS_DBG("#%d --------------- handler_thread starting on socket %p\n", sock->s_debug_nr, sock); if (!ok) goto done; brick->handler_running = true; wake_up_interruptible(&brick->startup_event); while (!brick_thread_should_stop() && mars_socket_is_alive(sock)) { struct mars_cmd cmd = {}; status = -EINTR; if (unlikely(!mars_global || !mars_global->global_power.button)) { MARS_DBG("system is not alive\n"); break; } status = mars_recv_struct(sock, &cmd, mars_cmd_meta); if (unlikely(status < 0)) { MARS_WRN("#%d recv cmd status = %d\n", sock->s_debug_nr, status); goto clean; } if (unlikely(!mars_socket_is_alive(sock))) { MARS_WRN("#%d is dead\n", sock->s_debug_nr); status = -EINTR; goto clean; } MARS_IO("#%d cmd = %d\n", sock->s_debug_nr, cmd.cmd_code); status = -EPROTO; switch (cmd.cmd_code & CMD_FLAG_MASK) { case CMD_NOP: status = 0; MARS_DBG("#%d got NOP operation\n", sock->s_debug_nr); break; case CMD_NOTIFY: status = 0; from_remote_trigger(); break; case CMD_GETINFO: { struct mars_info info = {}; status = GENERIC_INPUT_CALL(brick->inputs[0], mars_get_info, &info); if (status < 0) { break; } down(&brick->socket_sem); status = mars_send_struct(sock, &cmd, mars_cmd_meta); if (status >= 0) { status = mars_send_struct(sock, &info, mars_info_meta); } up(&brick->socket_sem); break; } case CMD_GETENTS: { struct mars_global local = { .dent_anchor = LIST_HEAD_INIT(local.dent_anchor), .brick_anchor = LIST_HEAD_INIT(local.brick_anchor), .global_power = { .button = true, }, .main_event = __WAIT_QUEUE_HEAD_INITIALIZER(local.main_event), }; status = -EINVAL; if (unlikely(!cmd.cmd_str1)) break; init_rwsem(&local.dent_mutex); init_rwsem(&local.brick_mutex); status = mars_dent_work(&local, "/mars", sizeof(struct mars_dent), light_checker, dummy_worker, &local, 3); down(&brick->socket_sem); status = mars_send_dent_list(sock, &local.dent_anchor); up(&brick->socket_sem); if (status < 0) { MARS_WRN("#%d could not send dentry information, status = %d\n", sock->s_debug_nr, status); } mars_free_dent_all(&local, &local.dent_anchor); break; } case CMD_CONNECT: { struct mars_brick *prev; const char *path = cmd.cmd_str1; status = -EINVAL; CHECK_PTR(path, err); CHECK_PTR_NULL(_bio_brick_type, err); if (!brick->global || !mars_global || !mars_global->global_power.button) { MARS_WRN("#%d system is not alive\n", sock->s_debug_nr); goto err; } prev = make_brick_all( brick->global, NULL, _set_server_bio_params, NULL, path, (const struct generic_brick_type*)_bio_brick_type, (const struct generic_brick_type*[]){}, 2, // start always path, (const char *[]){}, 0); if (likely(prev)) { status = generic_connect((void*)brick->inputs[0], (void*)prev->outputs[0]); if (unlikely(status < 0)) { MARS_ERR("#%d cannot connect to '%s'\n", sock->s_debug_nr, path); } prev->killme = true; } else { MARS_ERR("#%d cannot find brick '%s'\n", sock->s_debug_nr, path); } err: cmd.cmd_int1 = status; down(&brick->socket_sem); status = mars_send_struct(sock, &cmd, mars_cmd_meta); up(&brick->socket_sem); break; } case CMD_MREF: { #ifdef CONFIG_MARS_LOADAVG_LIMIT // quirk int my_load = (avenrun[0] + FIXED_1/200) >> FSHIFT; if (mars_max_loadavg && my_load >= mars_max_loadavg) { MARS_WRN("#%d loadavg %d too high (%d), aborting data traffic\n", sock->s_debug_nr, my_load, mars_max_loadavg); status = -EBUSY; break; } #endif status = server_io(brick, sock, &cmd); break; } case CMD_CB: MARS_ERR("#%d oops, as a server I should never get CMD_CB; something is wrong here - attack attempt??\n", sock->s_debug_nr); break; default: MARS_ERR("#%d unknown command %d\n", sock->s_debug_nr, cmd.cmd_code); } clean: brick_string_free(cmd.cmd_str1); if (status < 0) break; } mars_shutdown_socket(sock); mars_put_socket(sock); done: MARS_DBG("#%d handler_thread terminating, status = %d\n", sock->s_debug_nr, status); debug_nr = sock->s_debug_nr; MARS_DBG("#%d done.\n", debug_nr); atomic_dec(&server_handler_count); brick->killme = true; return status; } ////////////////// own brick / input / output operations ////////////////// static int server_get_info(struct server_output *output, struct mars_info *info) { struct server_input *input = output->brick->inputs[0]; return GENERIC_INPUT_CALL(input, mars_get_info, info); } static int server_ref_get(struct server_output *output, struct mref_object *mref) { struct server_input *input = output->brick->inputs[0]; return GENERIC_INPUT_CALL(input, mref_get, mref); } static void server_ref_put(struct server_output *output, struct mref_object *mref) { struct server_input *input = output->brick->inputs[0]; GENERIC_INPUT_CALL(input, mref_put, mref); } static void server_ref_io(struct server_output *output, struct mref_object *mref) { struct server_input *input = output->brick->inputs[0]; GENERIC_INPUT_CALL(input, mref_io, mref); } static int server_switch(struct server_brick *brick) { struct mars_socket *sock = &brick->handler_socket; int status = 0; if (brick->power.button) { static int version = 0; bool ok; if (brick->power.led_on) goto done; ok = mars_get_socket(sock); if (unlikely(!ok)) { status = -ENOENT; goto err; } mars_power_led_off((void*)brick, false); brick->cb_thread = brick_thread_create(cb_thread, brick, "mars_cb%d", version); if (unlikely(!brick->cb_thread)) { MARS_ERR("cannot create cb thread\n"); status = -ENOENT; goto err; } brick->handler_thread = brick_thread_create(handler_thread, brick, "mars_handler%d", version++); if (unlikely(!brick->handler_thread)) { MARS_ERR("cannot create handler thread\n"); brick_thread_stop(brick->cb_thread); brick->cb_thread = NULL; status = -ENOENT; goto err; } mars_power_led_on((void*)brick, true); } else if (!brick->power.led_off) { struct task_struct *thread; mars_power_led_on((void*)brick, false); mars_shutdown_socket(sock); thread = brick->handler_thread; if (thread) { brick->handler_thread = NULL; brick->handler_running = false; MARS_DBG("#%d stopping handler thread....\n", sock->s_debug_nr); brick_thread_stop(thread); } thread = brick->cb_thread; if (thread) { brick->cb_thread = NULL; brick->cb_running = false; MARS_DBG("#%d stopping callback thread....\n", sock->s_debug_nr); brick_thread_stop(thread); } mars_put_socket(sock); MARS_DBG("#%d socket s_count = %d\n", sock->s_debug_nr, atomic_read(&sock->s_count)); // do this only after _both_ threads have stopped... _clean_list(brick, &brick->cb_read_list); _clean_list(brick, &brick->cb_write_list); mars_power_led_off((void*)brick, true); } err: if (unlikely(status < 0)) { mars_power_led_off((void*)brick, true); mars_shutdown_socket(sock); mars_put_socket(sock); } done: return status; } //////////////// informational / statistics /////////////// static char *server_statistics(struct server_brick *brick, int verbose) { char *res = brick_string_alloc(1024); if (!res) return NULL; snprintf(res, 1024, "cb_running = %d " "handler_running = %d " "in_flight = %d\n", brick->cb_running, brick->handler_running, atomic_read(&brick->in_flight)); return res; } static void server_reset_statistics(struct server_brick *brick) { } //////////////// object / aspect constructors / destructors /////////////// static int server_mref_aspect_init_fn(struct generic_aspect *_ini) { struct server_mref_aspect *ini = (void*)_ini; INIT_LIST_HEAD(&ini->cb_head); return 0; } static void server_mref_aspect_exit_fn(struct generic_aspect *_ini) { struct server_mref_aspect *ini = (void*)_ini; CHECK_HEAD_EMPTY(&ini->cb_head); } MARS_MAKE_STATICS(server); ////////////////////// brick constructors / destructors //////////////////// static int server_brick_construct(struct server_brick *brick) { init_waitqueue_head(&brick->startup_event); init_waitqueue_head(&brick->cb_event); sema_init(&brick->socket_sem, 1); spin_lock_init(&brick->cb_lock); INIT_LIST_HEAD(&brick->cb_read_list); INIT_LIST_HEAD(&brick->cb_write_list); return 0; } static int server_brick_destruct(struct server_brick *brick) { CHECK_HEAD_EMPTY(&brick->cb_read_list); CHECK_HEAD_EMPTY(&brick->cb_write_list); return 0; } static int server_output_construct(struct server_output *output) { return 0; } ///////////////////////// static structs //////////////////////// static struct server_brick_ops server_brick_ops = { .brick_switch = server_switch, .brick_statistics = server_statistics, .reset_statistics = server_reset_statistics, }; static struct server_output_ops server_output_ops = { .mars_get_info = server_get_info, .mref_get = server_ref_get, .mref_put = server_ref_put, .mref_io = server_ref_io, }; const struct server_input_type server_input_type = { .type_name = "server_input", .input_size = sizeof(struct server_input), }; static const struct server_input_type *server_input_types[] = { &server_input_type, }; const struct server_output_type server_output_type = { .type_name = "server_output", .output_size = sizeof(struct server_output), .master_ops = &server_output_ops, .output_construct = &server_output_construct, }; static const struct server_output_type *server_output_types[] = { &server_output_type, }; const struct server_brick_type server_brick_type = { .type_name = "server_brick", .brick_size = sizeof(struct server_brick), .max_inputs = 1, .max_outputs = 0, .master_ops = &server_brick_ops, .aspect_types = server_aspect_types, .default_input_types = server_input_types, .default_output_types = server_output_types, .brick_construct = &server_brick_construct, .brick_destruct = &server_brick_destruct, }; EXPORT_SYMBOL_GPL(server_brick_type); /////////////////////////////////////////////////////////////////////// // strategy layer int server_show_statist = 0; EXPORT_SYMBOL_GPL(server_show_statist); static int _server_thread(void *data) { struct mars_global server_global = { .dent_anchor = LIST_HEAD_INIT(server_global.dent_anchor), .brick_anchor = LIST_HEAD_INIT(server_global.brick_anchor), .global_power = { .button = true, }, .main_event = __WAIT_QUEUE_HEAD_INITIALIZER(server_global.main_event), }; struct mars_socket *my_socket = data; char *id = my_id(); int status = 0; init_rwsem(&server_global.dent_mutex); init_rwsem(&server_global.brick_mutex); MARS_INF("-------- server starting on host '%s' ----------\n", id); while (!brick_thread_should_stop() && (!mars_global || !mars_global->global_power.button)) { MARS_DBG("system did not start up\n"); brick_msleep(5000); } MARS_INF("-------- server now working on host '%s' ----------\n", id); while (!brick_thread_should_stop() || !list_empty(&server_global.brick_anchor)) { struct server_brick *brick = NULL; struct mars_socket handler_socket = {}; server_global.global_version++; if (server_show_statist) show_statistics(&server_global, "server"); status = mars_kill_brick_when_possible(&server_global, &server_global.brick_anchor, false, NULL, true); MARS_DBG("kill server bricks (when possible) = %d\n", status); if (!mars_global || !mars_global->global_power.button) { brick_msleep(1000); continue; } status = mars_accept_socket(&handler_socket, my_socket); if (unlikely(status < 0 || !mars_socket_is_alive(&handler_socket))) { brick_msleep(500); if (status == -EAGAIN) continue; // without error message MARS_WRN("accept status = %d\n", status); brick_msleep(1000); continue; } handler_socket.s_shutdown_on_err = true; MARS_DBG("got new connection #%d\n", handler_socket.s_debug_nr); brick = (void*)mars_make_brick(&server_global, NULL, &server_brick_type, "handler", "handler"); if (!brick) { MARS_ERR("cannot create server instance\n"); mars_shutdown_socket(&handler_socket); mars_put_socket(&handler_socket); brick_msleep(2000); continue; } memcpy(&brick->handler_socket, &handler_socket, sizeof(struct mars_socket)); atomic_inc(&server_handler_count); /* TODO: check authorization. */ brick->power.button = true; status = server_switch(brick); if (unlikely(status < 0)) { MARS_ERR("cannot switch on server brick, status = %d\n", status); goto err; } // further references are usually held by the threads mars_put_socket(&brick->handler_socket); /* fire and forget.... * the new instance is now responsible for itself. */ brick = NULL; brick_msleep(100); continue; err: if (brick) { mars_shutdown_socket(&brick->handler_socket); mars_put_socket(&brick->handler_socket); status = mars_kill_brick((void*)brick); if (status < 0) { BRICK_ERR("kill status = %d, giving up\n", status); } brick = NULL; atomic_dec(&server_handler_count); } brick_msleep(2000); } MARS_INF("-------- cleaning up ----------\n"); mars_kill_brick_all(&server_global, &server_global.brick_anchor, false); //cleanup_mm(); MARS_INF("-------- done status = %d ----------\n", status); return status; } ////////////////// module init stuff ///////////////////////// struct mars_limiter server_limiter = { .lim_max_rate = 0, }; EXPORT_SYMBOL_GPL(server_limiter); void __exit exit_mars_server(void) { int i; MARS_INF("exit_server()\n"); server_unregister_brick_type(); for (i = 0; i < NR_SOCKETS; i++) { if (server_thread[i]) { MARS_INF("stopping server thread %d...\n", i); brick_thread_stop(server_thread[i]); } MARS_INF("closing server socket %d...\n", i); mars_put_socket(&server_socket[i]); } } int __init init_mars_server(void) { int i; MARS_INF("init_server()\n"); for (i = 0; i < NR_SOCKETS; i++) { struct sockaddr_storage sockaddr = {}; char tmp[16]; int status; sprintf(tmp, ":%d", mars_net_default_port + i); status = mars_create_sockaddr(&sockaddr, tmp); if (unlikely(status < 0)) { exit_mars_server(); return status; } status = mars_create_socket(&server_socket[i], &sockaddr, true); if (unlikely(status < 0)) { MARS_ERR("could not create server socket %d, status = %d\n", i, status); exit_mars_server(); return status; } server_thread[i] = brick_thread_create(_server_thread, &server_socket[i], "mars_server_%d", i); if (unlikely(!server_thread[i] || IS_ERR(server_thread[i]))) { MARS_ERR("could not create server thread %d\n", i); exit_mars_server(); return -ENOENT; } } return server_register_brick_type(); } #ifndef CONFIG_MARS_HAVE_BIGMODULE MODULE_DESCRIPTION("MARS server brick"); MODULE_AUTHOR("Thomas Schoebel-Theuer "); MODULE_LICENSE("GPL"); module_init(init_mars_server); module_exit(exit_mars_server); #endif