// SPDX-License-Identifier: GPL-2.0-only /* * Linux WiMAX * Initialization, addition and removal of wimax devices * * Copyright (C) 2005-2006 Intel Corporation * Inaky Perez-Gonzalez * * This implements: * * - basic life cycle of 'struct wimax_dev' [wimax_dev_*()]; on * addition/registration initialize all subfields and allocate * generic netlink resources for user space communication. On * removal/unregistration, undo all that. * * - device state machine [wimax_state_change()] and support to send * reports to user space when the state changes * [wimax_gnl_re_state_change*()]. * * See include/net/wimax.h for rationales and design. * * ROADMAP * * [__]wimax_state_change() Called by drivers to update device's state * wimax_gnl_re_state_change_alloc() * wimax_gnl_re_state_change_send() * * wimax_dev_init() Init a device * wimax_dev_add() Register * wimax_rfkill_add() * wimax_gnl_add() Register all the generic netlink resources. * wimax_id_table_add() * wimax_dev_rm() Unregister * wimax_id_table_rm() * wimax_gnl_rm() * wimax_rfkill_rm() */ #include #include #include #include #include "linux-wimax.h" #include #include "wimax-internal.h" #define D_SUBMODULE stack #include "debug-levels.h" static char wimax_debug_params[128]; module_param_string(debug, wimax_debug_params, sizeof(wimax_debug_params), 0644); MODULE_PARM_DESC(debug, "String of space-separated NAME:VALUE pairs, where NAMEs " "are the different debug submodules and VALUE are the " "initial debug value to set."); /* * Allocate a Report State Change message * * @header: save it, you need it for _send() * * Creates and fills a basic state change message; different code * paths can then add more attributes to the message as needed. * * Use wimax_gnl_re_state_change_send() to send the returned skb. * * Returns: skb with the genl message if ok, IS_ERR() ptr on error * with an errno code. */ static struct sk_buff *wimax_gnl_re_state_change_alloc( struct wimax_dev *wimax_dev, enum wimax_st new_state, enum wimax_st old_state, void **header) { int result; struct device *dev = wimax_dev_to_dev(wimax_dev); void *data; struct sk_buff *report_skb; d_fnstart(3, dev, "(wimax_dev %p new_state %u old_state %u)\n", wimax_dev, new_state, old_state); result = -ENOMEM; report_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); if (report_skb == NULL) { dev_err(dev, "RE_STCH: can't create message\n"); goto error_new; } /* FIXME: sending a group ID as the seq is wrong */ data = genlmsg_put(report_skb, 0, wimax_gnl_family.mcgrp_offset, &wimax_gnl_family, 0, WIMAX_GNL_RE_STATE_CHANGE); if (data == NULL) { dev_err(dev, "RE_STCH: can't put data into message\n"); goto error_put; } *header = data; result = nla_put_u8(report_skb, WIMAX_GNL_STCH_STATE_OLD, old_state); if (result < 0) { dev_err(dev, "RE_STCH: Error adding OLD attr: %d\n", result); goto error_put; } result = nla_put_u8(report_skb, WIMAX_GNL_STCH_STATE_NEW, new_state); if (result < 0) { dev_err(dev, "RE_STCH: Error adding NEW attr: %d\n", result); goto error_put; } result = nla_put_u32(report_skb, WIMAX_GNL_STCH_IFIDX, wimax_dev->net_dev->ifindex); if (result < 0) { dev_err(dev, "RE_STCH: Error adding IFINDEX attribute\n"); goto error_put; } d_fnend(3, dev, "(wimax_dev %p new_state %u old_state %u) = %p\n", wimax_dev, new_state, old_state, report_skb); return report_skb; error_put: nlmsg_free(report_skb); error_new: d_fnend(3, dev, "(wimax_dev %p new_state %u old_state %u) = %d\n", wimax_dev, new_state, old_state, result); return ERR_PTR(result); } /* * Send a Report State Change message (as created with _alloc). * * @report_skb: as returned by wimax_gnl_re_state_change_alloc() * @header: as returned by wimax_gnl_re_state_change_alloc() * * Returns: 0 if ok, < 0 errno code on error. * * If the message is NULL, pretend it didn't happen. */ static int wimax_gnl_re_state_change_send( struct wimax_dev *wimax_dev, struct sk_buff *report_skb, void *header) { int result = 0; struct device *dev = wimax_dev_to_dev(wimax_dev); d_fnstart(3, dev, "(wimax_dev %p report_skb %p)\n", wimax_dev, report_skb); if (report_skb == NULL) { result = -ENOMEM; goto out; } genlmsg_end(report_skb, header); genlmsg_multicast(&wimax_gnl_family, report_skb, 0, 0, GFP_KERNEL); out: d_fnend(3, dev, "(wimax_dev %p report_skb %p) = %d\n", wimax_dev, report_skb, result); return result; } static void __check_new_state(enum wimax_st old_state, enum wimax_st new_state, unsigned int allowed_states_bm) { if (WARN_ON(((1 << new_state) & allowed_states_bm) == 0)) { pr_err("SW BUG! Forbidden state change %u -> %u\n", old_state, new_state); } } /* * Set the current state of a WiMAX device [unlocking version of * wimax_state_change(). */ void __wimax_state_change(struct wimax_dev *wimax_dev, enum wimax_st new_state) { struct device *dev = wimax_dev_to_dev(wimax_dev); enum wimax_st old_state = wimax_dev->state; struct sk_buff *stch_skb; void *header; d_fnstart(3, dev, "(wimax_dev %p new_state %u [old %u])\n", wimax_dev, new_state, old_state); if (WARN_ON(new_state >= __WIMAX_ST_INVALID)) { dev_err(dev, "SW BUG: requesting invalid state %u\n", new_state); goto out; } if (old_state == new_state) goto out; header = NULL; /* gcc complains? can't grok why */ stch_skb = wimax_gnl_re_state_change_alloc( wimax_dev, new_state, old_state, &header); /* Verify the state transition and do exit-from-state actions */ switch (old_state) { case __WIMAX_ST_NULL: __check_new_state(old_state, new_state, 1 << WIMAX_ST_DOWN); break; case WIMAX_ST_DOWN: __check_new_state(old_state, new_state, 1 << __WIMAX_ST_QUIESCING | 1 << WIMAX_ST_UNINITIALIZED | 1 << WIMAX_ST_RADIO_OFF); break; case __WIMAX_ST_QUIESCING: __check_new_state(old_state, new_state, 1 << WIMAX_ST_DOWN); break; case WIMAX_ST_UNINITIALIZED: __check_new_state(old_state, new_state, 1 << __WIMAX_ST_QUIESCING | 1 << WIMAX_ST_RADIO_OFF); break; case WIMAX_ST_RADIO_OFF: __check_new_state(old_state, new_state, 1 << __WIMAX_ST_QUIESCING | 1 << WIMAX_ST_READY); break; case WIMAX_ST_READY: __check_new_state(old_state, new_state, 1 << __WIMAX_ST_QUIESCING | 1 << WIMAX_ST_RADIO_OFF | 1 << WIMAX_ST_SCANNING | 1 << WIMAX_ST_CONNECTING | 1 << WIMAX_ST_CONNECTED); break; case WIMAX_ST_SCANNING: __check_new_state(old_state, new_state, 1 << __WIMAX_ST_QUIESCING | 1 << WIMAX_ST_RADIO_OFF | 1 << WIMAX_ST_READY | 1 << WIMAX_ST_CONNECTING | 1 << WIMAX_ST_CONNECTED); break; case WIMAX_ST_CONNECTING: __check_new_state(old_state, new_state, 1 << __WIMAX_ST_QUIESCING | 1 << WIMAX_ST_RADIO_OFF | 1 << WIMAX_ST_READY | 1 << WIMAX_ST_SCANNING | 1 << WIMAX_ST_CONNECTED); break; case WIMAX_ST_CONNECTED: __check_new_state(old_state, new_state, 1 << __WIMAX_ST_QUIESCING | 1 << WIMAX_ST_RADIO_OFF | 1 << WIMAX_ST_READY); netif_tx_disable(wimax_dev->net_dev); netif_carrier_off(wimax_dev->net_dev); break; case __WIMAX_ST_INVALID: default: dev_err(dev, "SW BUG: wimax_dev %p is in unknown state %u\n", wimax_dev, wimax_dev->state); WARN_ON(1); goto out; } /* Execute the actions of entry to the new state */ switch (new_state) { case __WIMAX_ST_NULL: dev_err(dev, "SW BUG: wimax_dev %p entering NULL state " "from %u\n", wimax_dev, wimax_dev->state); WARN_ON(1); /* Nobody can enter this state */ break; case WIMAX_ST_DOWN: break; case __WIMAX_ST_QUIESCING: break; case WIMAX_ST_UNINITIALIZED: break; case WIMAX_ST_RADIO_OFF: break; case WIMAX_ST_READY: break; case WIMAX_ST_SCANNING: break; case WIMAX_ST_CONNECTING: break; case WIMAX_ST_CONNECTED: netif_carrier_on(wimax_dev->net_dev); netif_wake_queue(wimax_dev->net_dev); break; case __WIMAX_ST_INVALID: default: BUG(); } __wimax_state_set(wimax_dev, new_state); if (!IS_ERR(stch_skb)) wimax_gnl_re_state_change_send(wimax_dev, stch_skb, header); out: d_fnend(3, dev, "(wimax_dev %p new_state %u [old %u]) = void\n", wimax_dev, new_state, old_state); } /** * wimax_state_change - Set the current state of a WiMAX device * * @wimax_dev: WiMAX device descriptor (properly referenced) * @new_state: New state to switch to * * This implements the state changes for the wimax devices. It will * * - verify that the state transition is legal (for now it'll just * print a warning if not) according to the table in * linux/wimax.h's documentation for 'enum wimax_st'. * * - perform the actions needed for leaving the current state and * whichever are needed for entering the new state. * * - issue a report to user space indicating the new state (and an * optional payload with information about the new state). * * NOTE: @wimax_dev must be locked */ void wimax_state_change(struct wimax_dev *wimax_dev, enum wimax_st new_state) { /* * A driver cannot take the wimax_dev out of the * __WIMAX_ST_NULL state unless by calling wimax_dev_add(). If * the wimax_dev's state is still NULL, we ignore any request * to change its state because it means it hasn't been yet * registered. * * There is no need to complain about it, as routines that * call this might be shared from different code paths that * are called before or after wimax_dev_add() has done its * job. */ mutex_lock(&wimax_dev->mutex); if (wimax_dev->state > __WIMAX_ST_NULL) __wimax_state_change(wimax_dev, new_state); mutex_unlock(&wimax_dev->mutex); } EXPORT_SYMBOL_GPL(wimax_state_change); /** * wimax_state_get() - Return the current state of a WiMAX device * * @wimax_dev: WiMAX device descriptor * * Returns: Current state of the device according to its driver. */ enum wimax_st wimax_state_get(struct wimax_dev *wimax_dev) { enum wimax_st state; mutex_lock(&wimax_dev->mutex); state = wimax_dev->state; mutex_unlock(&wimax_dev->mutex); return state; } EXPORT_SYMBOL_GPL(wimax_state_get); /** * wimax_dev_init - initialize a newly allocated instance * * @wimax_dev: WiMAX device descriptor to initialize. * * Initializes fields of a freshly allocated @wimax_dev instance. This * function assumes that after allocation, the memory occupied by * @wimax_dev was zeroed. */ void wimax_dev_init(struct wimax_dev *wimax_dev) { INIT_LIST_HEAD(&wimax_dev->id_table_node); __wimax_state_set(wimax_dev, __WIMAX_ST_NULL); mutex_init(&wimax_dev->mutex); mutex_init(&wimax_dev->mutex_reset); } EXPORT_SYMBOL_GPL(wimax_dev_init); /* * There are multiple enums reusing the same values, adding * others is only possible if they use a compatible policy. */ static const struct nla_policy wimax_gnl_policy[WIMAX_GNL_ATTR_MAX + 1] = { /* * WIMAX_GNL_RESET_IFIDX, WIMAX_GNL_RFKILL_IFIDX, * WIMAX_GNL_STGET_IFIDX, WIMAX_GNL_MSG_IFIDX */ [1] = { .type = NLA_U32, }, /* * WIMAX_GNL_RFKILL_STATE, WIMAX_GNL_MSG_PIPE_NAME */ [2] = { .type = NLA_U32, }, /* enum wimax_rf_state */ /* * WIMAX_GNL_MSG_DATA */ [3] = { .type = NLA_UNSPEC, }, /* libnl doesn't grok BINARY yet */ }; static const struct genl_small_ops wimax_gnl_ops[] = { { .cmd = WIMAX_GNL_OP_MSG_FROM_USER, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = GENL_ADMIN_PERM, .doit = wimax_gnl_doit_msg_from_user, }, { .cmd = WIMAX_GNL_OP_RESET, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = GENL_ADMIN_PERM, .doit = wimax_gnl_doit_reset, }, { .cmd = WIMAX_GNL_OP_RFKILL, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = GENL_ADMIN_PERM, .doit = wimax_gnl_doit_rfkill, }, { .cmd = WIMAX_GNL_OP_STATE_GET, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .flags = GENL_ADMIN_PERM, .doit = wimax_gnl_doit_state_get, }, }; static size_t wimax_addr_scnprint(char *addr_str, size_t addr_str_size, unsigned char *addr, size_t addr_len) { unsigned int cnt, total; for (total = cnt = 0; cnt < addr_len; cnt++) total += scnprintf(addr_str + total, addr_str_size - total, "%02x%c", addr[cnt], cnt == addr_len - 1 ? '\0' : ':'); return total; } /** * wimax_dev_add - Register a new WiMAX device * * @wimax_dev: WiMAX device descriptor (as embedded in your @net_dev's * priv data). You must have called wimax_dev_init() on it before. * * @net_dev: net device the @wimax_dev is associated with. The * function expects SET_NETDEV_DEV() and register_netdev() were * already called on it. * * Registers the new WiMAX device, sets up the user-kernel control * interface (generic netlink) and common WiMAX infrastructure. * * Note that the parts that will allow interaction with user space are * setup at the very end, when the rest is in place, as once that * happens, the driver might get user space control requests via * netlink or from debugfs that might translate into calls into * wimax_dev->op_*(). */ int wimax_dev_add(struct wimax_dev *wimax_dev, struct net_device *net_dev) { int result; struct device *dev = net_dev->dev.parent; char addr_str[32]; d_fnstart(3, dev, "(wimax_dev %p net_dev %p)\n", wimax_dev, net_dev); /* Do the RFKILL setup before locking, as RFKILL will call * into our functions. */ wimax_dev->net_dev = net_dev; result = wimax_rfkill_add(wimax_dev); if (result < 0) goto error_rfkill_add; /* Set up user-space interaction */ mutex_lock(&wimax_dev->mutex); wimax_id_table_add(wimax_dev); wimax_debugfs_add(wimax_dev); __wimax_state_set(wimax_dev, WIMAX_ST_DOWN); mutex_unlock(&wimax_dev->mutex); wimax_addr_scnprint(addr_str, sizeof(addr_str), net_dev->dev_addr, net_dev->addr_len); dev_err(dev, "WiMAX interface %s (%s) ready\n", net_dev->name, addr_str); d_fnend(3, dev, "(wimax_dev %p net_dev %p) = 0\n", wimax_dev, net_dev); return 0; error_rfkill_add: d_fnend(3, dev, "(wimax_dev %p net_dev %p) = %d\n", wimax_dev, net_dev, result); return result; } EXPORT_SYMBOL_GPL(wimax_dev_add); /** * wimax_dev_rm - Unregister an existing WiMAX device * * @wimax_dev: WiMAX device descriptor * * Unregisters a WiMAX device previously registered for use with * wimax_add_rm(). * * IMPORTANT! Must call before calling unregister_netdev(). * * After this function returns, you will not get any more user space * control requests (via netlink or debugfs) and thus to wimax_dev->ops. * * Reentrancy control is ensured by setting the state to * %__WIMAX_ST_QUIESCING. rfkill operations coming through * wimax_*rfkill*() will be stopped by the quiescing state; ops coming * from the rfkill subsystem will be stopped by the support being * removed by wimax_rfkill_rm(). */ void wimax_dev_rm(struct wimax_dev *wimax_dev) { d_fnstart(3, NULL, "(wimax_dev %p)\n", wimax_dev); mutex_lock(&wimax_dev->mutex); __wimax_state_change(wimax_dev, __WIMAX_ST_QUIESCING); wimax_debugfs_rm(wimax_dev); wimax_id_table_rm(wimax_dev); __wimax_state_change(wimax_dev, WIMAX_ST_DOWN); mutex_unlock(&wimax_dev->mutex); wimax_rfkill_rm(wimax_dev); d_fnend(3, NULL, "(wimax_dev %p) = void\n", wimax_dev); } EXPORT_SYMBOL_GPL(wimax_dev_rm); /* Debug framework control of debug levels */ struct d_level D_LEVEL[] = { D_SUBMODULE_DEFINE(debugfs), D_SUBMODULE_DEFINE(id_table), D_SUBMODULE_DEFINE(op_msg), D_SUBMODULE_DEFINE(op_reset), D_SUBMODULE_DEFINE(op_rfkill), D_SUBMODULE_DEFINE(op_state_get), D_SUBMODULE_DEFINE(stack), }; size_t D_LEVEL_SIZE = ARRAY_SIZE(D_LEVEL); static const struct genl_multicast_group wimax_gnl_mcgrps[] = { { .name = "msg", }, }; struct genl_family wimax_gnl_family __ro_after_init = { .name = "WiMAX", .version = WIMAX_GNL_VERSION, .hdrsize = 0, .maxattr = WIMAX_GNL_ATTR_MAX, .policy = wimax_gnl_policy, .module = THIS_MODULE, .small_ops = wimax_gnl_ops, .n_small_ops = ARRAY_SIZE(wimax_gnl_ops), .mcgrps = wimax_gnl_mcgrps, .n_mcgrps = ARRAY_SIZE(wimax_gnl_mcgrps), }; /* Shutdown the wimax stack */ static int __init wimax_subsys_init(void) { int result; d_fnstart(4, NULL, "()\n"); d_parse_params(D_LEVEL, D_LEVEL_SIZE, wimax_debug_params, "wimax.debug"); result = genl_register_family(&wimax_gnl_family); if (unlikely(result < 0)) { pr_err("cannot register generic netlink family: %d\n", result); goto error_register_family; } d_fnend(4, NULL, "() = 0\n"); return 0; error_register_family: d_fnend(4, NULL, "() = %d\n", result); return result; } module_init(wimax_subsys_init); /* Shutdown the wimax stack */ static void __exit wimax_subsys_exit(void) { wimax_id_table_release(); genl_unregister_family(&wimax_gnl_family); } module_exit(wimax_subsys_exit); MODULE_AUTHOR("Intel Corporation "); MODULE_DESCRIPTION("Linux WiMAX stack"); MODULE_LICENSE("GPL");