/* * UWB reservation management. * * Copyright (C) 2008 Cambridge Silicon Radio Ltd. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License version * 2 as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ #include <linux/kernel.h> #include <linux/uwb.h> #include <linux/slab.h> #include <linux/random.h> #include <linux/export.h> #include "uwb-internal.h" static void uwb_rsv_timer(unsigned long arg); static const char *rsv_states[] = { [UWB_RSV_STATE_NONE] = "none ", [UWB_RSV_STATE_O_INITIATED] = "o initiated ", [UWB_RSV_STATE_O_PENDING] = "o pending ", [UWB_RSV_STATE_O_MODIFIED] = "o modified ", [UWB_RSV_STATE_O_ESTABLISHED] = "o established ", [UWB_RSV_STATE_O_TO_BE_MOVED] = "o to be moved ", [UWB_RSV_STATE_O_MOVE_EXPANDING] = "o move expanding", [UWB_RSV_STATE_O_MOVE_COMBINING] = "o move combining", [UWB_RSV_STATE_O_MOVE_REDUCING] = "o move reducing ", [UWB_RSV_STATE_T_ACCEPTED] = "t accepted ", [UWB_RSV_STATE_T_CONFLICT] = "t conflict ", [UWB_RSV_STATE_T_PENDING] = "t pending ", [UWB_RSV_STATE_T_DENIED] = "t denied ", [UWB_RSV_STATE_T_RESIZED] = "t resized ", [UWB_RSV_STATE_T_EXPANDING_ACCEPTED] = "t expanding acc ", [UWB_RSV_STATE_T_EXPANDING_CONFLICT] = "t expanding conf", [UWB_RSV_STATE_T_EXPANDING_PENDING] = "t expanding pend", [UWB_RSV_STATE_T_EXPANDING_DENIED] = "t expanding den ", }; static const char *rsv_types[] = { [UWB_DRP_TYPE_ALIEN_BP] = "alien-bp", [UWB_DRP_TYPE_HARD] = "hard", [UWB_DRP_TYPE_SOFT] = "soft", [UWB_DRP_TYPE_PRIVATE] = "private", [UWB_DRP_TYPE_PCA] = "pca", }; bool uwb_rsv_has_two_drp_ies(struct uwb_rsv *rsv) { static const bool has_two_drp_ies[] = { [UWB_RSV_STATE_O_INITIATED] = false, [UWB_RSV_STATE_O_PENDING] = false, [UWB_RSV_STATE_O_MODIFIED] = false, [UWB_RSV_STATE_O_ESTABLISHED] = false, [UWB_RSV_STATE_O_TO_BE_MOVED] = false, [UWB_RSV_STATE_O_MOVE_COMBINING] = false, [UWB_RSV_STATE_O_MOVE_REDUCING] = false, [UWB_RSV_STATE_O_MOVE_EXPANDING] = true, [UWB_RSV_STATE_T_ACCEPTED] = false, [UWB_RSV_STATE_T_CONFLICT] = false, [UWB_RSV_STATE_T_PENDING] = false, [UWB_RSV_STATE_T_DENIED] = false, [UWB_RSV_STATE_T_RESIZED] = false, [UWB_RSV_STATE_T_EXPANDING_ACCEPTED] = true, [UWB_RSV_STATE_T_EXPANDING_CONFLICT] = true, [UWB_RSV_STATE_T_EXPANDING_PENDING] = true, [UWB_RSV_STATE_T_EXPANDING_DENIED] = true, }; return has_two_drp_ies[rsv->state]; } /** * uwb_rsv_state_str - return a string for a reservation state * @state: the reservation state. */ const char *uwb_rsv_state_str(enum uwb_rsv_state state) { if (state < UWB_RSV_STATE_NONE || state >= UWB_RSV_STATE_LAST) return "unknown"; return rsv_states[state]; } EXPORT_SYMBOL_GPL(uwb_rsv_state_str); /** * uwb_rsv_type_str - return a string for a reservation type * @type: the reservation type */ const char *uwb_rsv_type_str(enum uwb_drp_type type) { if (type < UWB_DRP_TYPE_ALIEN_BP || type > UWB_DRP_TYPE_PCA) return "invalid"; return rsv_types[type]; } EXPORT_SYMBOL_GPL(uwb_rsv_type_str); void uwb_rsv_dump(char *text, struct uwb_rsv *rsv) { struct device *dev = &rsv->rc->uwb_dev.dev; struct uwb_dev_addr devaddr; char owner[UWB_ADDR_STRSIZE], target[UWB_ADDR_STRSIZE]; uwb_dev_addr_print(owner, sizeof(owner), &rsv->owner->dev_addr); if (rsv->target.type == UWB_RSV_TARGET_DEV) devaddr = rsv->target.dev->dev_addr; else devaddr = rsv->target.devaddr; uwb_dev_addr_print(target, sizeof(target), &devaddr); dev_dbg(dev, "rsv %s %s -> %s: %s\n", text, owner, target, uwb_rsv_state_str(rsv->state)); } static void uwb_rsv_release(struct kref *kref) { struct uwb_rsv *rsv = container_of(kref, struct uwb_rsv, kref); kfree(rsv); } void uwb_rsv_get(struct uwb_rsv *rsv) { kref_get(&rsv->kref); } void uwb_rsv_put(struct uwb_rsv *rsv) { kref_put(&rsv->kref, uwb_rsv_release); } /* * Get a free stream index for a reservation. * * If the target is a DevAddr (e.g., a WUSB cluster reservation) then * the stream is allocated from a pool of per-RC stream indexes, * otherwise a unique stream index for the target is selected. */ static int uwb_rsv_get_stream(struct uwb_rsv *rsv) { struct uwb_rc *rc = rsv->rc; struct device *dev = &rc->uwb_dev.dev; unsigned long *streams_bm; int stream; switch (rsv->target.type) { case UWB_RSV_TARGET_DEV: streams_bm = rsv->target.dev->streams; break; case UWB_RSV_TARGET_DEVADDR: streams_bm = rc->uwb_dev.streams; break; default: return -EINVAL; } stream = find_first_zero_bit(streams_bm, UWB_NUM_STREAMS); if (stream >= UWB_NUM_STREAMS) { dev_err(dev, "%s: no available stream found\n", __func__); return -EBUSY; } rsv->stream = stream; set_bit(stream, streams_bm); dev_dbg(dev, "get stream %d\n", rsv->stream); return 0; } static void uwb_rsv_put_stream(struct uwb_rsv *rsv) { struct uwb_rc *rc = rsv->rc; struct device *dev = &rc->uwb_dev.dev; unsigned long *streams_bm; switch (rsv->target.type) { case UWB_RSV_TARGET_DEV: streams_bm = rsv->target.dev->streams; break; case UWB_RSV_TARGET_DEVADDR: streams_bm = rc->uwb_dev.streams; break; default: return; } clear_bit(rsv->stream, streams_bm); dev_dbg(dev, "put stream %d\n", rsv->stream); } void uwb_rsv_backoff_win_timer(unsigned long arg) { struct uwb_drp_backoff_win *bow = (struct uwb_drp_backoff_win *)arg; struct uwb_rc *rc = container_of(bow, struct uwb_rc, bow); struct device *dev = &rc->uwb_dev.dev; bow->can_reserve_extra_mases = true; if (bow->total_expired <= 4) { bow->total_expired++; } else { /* after 4 backoff window has expired we can exit from * the backoff procedure */ bow->total_expired = 0; bow->window = UWB_DRP_BACKOFF_WIN_MIN >> 1; } dev_dbg(dev, "backoff_win_timer total_expired=%d, n=%d\n: ", bow->total_expired, bow->n); /* try to relocate all the "to be moved" relocations */ uwb_rsv_handle_drp_avail_change(rc); } void uwb_rsv_backoff_win_increment(struct uwb_rc *rc) { struct uwb_drp_backoff_win *bow = &rc->bow; struct device *dev = &rc->uwb_dev.dev; unsigned timeout_us; dev_dbg(dev, "backoff_win_increment: window=%d\n", bow->window); bow->can_reserve_extra_mases = false; if((bow->window << 1) == UWB_DRP_BACKOFF_WIN_MAX) return; bow->window <<= 1; bow->n = prandom_u32() & (bow->window - 1); dev_dbg(dev, "new_window=%d, n=%d\n: ", bow->window, bow->n); /* reset the timer associated variables */ timeout_us = bow->n * UWB_SUPERFRAME_LENGTH_US; bow->total_expired = 0; mod_timer(&bow->timer, jiffies + usecs_to_jiffies(timeout_us)); } static void uwb_rsv_stroke_timer(struct uwb_rsv *rsv) { int sframes = UWB_MAX_LOST_BEACONS; /* * Multicast reservations can become established within 1 * super frame and should not be terminated if no response is * received. */ if (rsv->state == UWB_RSV_STATE_NONE) { sframes = 0; } else if (rsv->is_multicast) { if (rsv->state == UWB_RSV_STATE_O_INITIATED || rsv->state == UWB_RSV_STATE_O_MOVE_EXPANDING || rsv->state == UWB_RSV_STATE_O_MOVE_COMBINING || rsv->state == UWB_RSV_STATE_O_MOVE_REDUCING) sframes = 1; if (rsv->state == UWB_RSV_STATE_O_ESTABLISHED) sframes = 0; } if (sframes > 0) { /* * Add an additional 2 superframes to account for the * time to send the SET DRP IE command. */ unsigned timeout_us = (sframes + 2) * UWB_SUPERFRAME_LENGTH_US; mod_timer(&rsv->timer, jiffies + usecs_to_jiffies(timeout_us)); } else del_timer(&rsv->timer); } /* * Update a reservations state, and schedule an update of the * transmitted DRP IEs. */ static void uwb_rsv_state_update(struct uwb_rsv *rsv, enum uwb_rsv_state new_state) { rsv->state = new_state; rsv->ie_valid = false; uwb_rsv_dump("SU", rsv); uwb_rsv_stroke_timer(rsv); uwb_rsv_sched_update(rsv->rc); } static void uwb_rsv_callback(struct uwb_rsv *rsv) { if (rsv->callback) rsv->callback(rsv); } void uwb_rsv_set_state(struct uwb_rsv *rsv, enum uwb_rsv_state new_state) { struct uwb_rsv_move *mv = &rsv->mv; if (rsv->state == new_state) { switch (rsv->state) { case UWB_RSV_STATE_O_ESTABLISHED: case UWB_RSV_STATE_O_MOVE_EXPANDING: case UWB_RSV_STATE_O_MOVE_COMBINING: case UWB_RSV_STATE_O_MOVE_REDUCING: case UWB_RSV_STATE_T_ACCEPTED: case UWB_RSV_STATE_T_EXPANDING_ACCEPTED: case UWB_RSV_STATE_T_RESIZED: case UWB_RSV_STATE_NONE: uwb_rsv_stroke_timer(rsv); break; default: /* Expecting a state transition so leave timer as-is. */ break; } return; } uwb_rsv_dump("SC", rsv); switch (new_state) { case UWB_RSV_STATE_NONE: uwb_rsv_state_update(rsv, UWB_RSV_STATE_NONE); uwb_rsv_remove(rsv); uwb_rsv_callback(rsv); break; case UWB_RSV_STATE_O_INITIATED: uwb_rsv_state_update(rsv, UWB_RSV_STATE_O_INITIATED); break; case UWB_RSV_STATE_O_PENDING: uwb_rsv_state_update(rsv, UWB_RSV_STATE_O_PENDING); break; case UWB_RSV_STATE_O_MODIFIED: /* in the companion there are the MASes to drop */ bitmap_andnot(rsv->mas.bm, rsv->mas.bm, mv->companion_mas.bm, UWB_NUM_MAS); uwb_rsv_state_update(rsv, UWB_RSV_STATE_O_MODIFIED); break; case UWB_RSV_STATE_O_ESTABLISHED: if (rsv->state == UWB_RSV_STATE_O_MODIFIED || rsv->state == UWB_RSV_STATE_O_MOVE_REDUCING) { uwb_drp_avail_release(rsv->rc, &mv->companion_mas); rsv->needs_release_companion_mas = false; } uwb_drp_avail_reserve(rsv->rc, &rsv->mas); uwb_rsv_state_update(rsv, UWB_RSV_STATE_O_ESTABLISHED); uwb_rsv_callback(rsv); break; case UWB_RSV_STATE_O_MOVE_EXPANDING: rsv->needs_release_companion_mas = true; uwb_rsv_state_update(rsv, UWB_RSV_STATE_O_MOVE_EXPANDING); break; case UWB_RSV_STATE_O_MOVE_COMBINING: rsv->needs_release_companion_mas = false; uwb_drp_avail_reserve(rsv->rc, &mv->companion_mas); bitmap_or(rsv->mas.bm, rsv->mas.bm, mv->companion_mas.bm, UWB_NUM_MAS); rsv->mas.safe += mv->companion_mas.safe; rsv->mas.unsafe += mv->companion_mas.unsafe; uwb_rsv_state_update(rsv, UWB_RSV_STATE_O_MOVE_COMBINING); break; case UWB_RSV_STATE_O_MOVE_REDUCING: bitmap_andnot(mv->companion_mas.bm, rsv->mas.bm, mv->final_mas.bm, UWB_NUM_MAS); rsv->needs_release_companion_mas = true; rsv->mas.safe = mv->final_mas.safe; rsv->mas.unsafe = mv->final_mas.unsafe; bitmap_copy(rsv->mas.bm, mv->final_mas.bm, UWB_NUM_MAS); bitmap_copy(rsv->mas.unsafe_bm, mv->final_mas.unsafe_bm, UWB_NUM_MAS); uwb_rsv_state_update(rsv, UWB_RSV_STATE_O_MOVE_REDUCING); break; case UWB_RSV_STATE_T_ACCEPTED: case UWB_RSV_STATE_T_RESIZED: rsv->needs_release_companion_mas = false; uwb_drp_avail_reserve(rsv->rc, &rsv->mas); uwb_rsv_state_update(rsv, UWB_RSV_STATE_T_ACCEPTED); uwb_rsv_callback(rsv); break; case UWB_RSV_STATE_T_DENIED: uwb_rsv_state_update(rsv, UWB_RSV_STATE_T_DENIED); break; case UWB_RSV_STATE_T_CONFLICT: uwb_rsv_state_update(rsv, UWB_RSV_STATE_T_CONFLICT); break; case UWB_RSV_STATE_T_PENDING: uwb_rsv_state_update(rsv, UWB_RSV_STATE_T_PENDING); break; case UWB_RSV_STATE_T_EXPANDING_ACCEPTED: rsv->needs_release_companion_mas = true; uwb_drp_avail_reserve(rsv->rc, &mv->companion_mas); uwb_rsv_state_update(rsv, UWB_RSV_STATE_T_EXPANDING_ACCEPTED); break; default: dev_err(&rsv->rc->uwb_dev.dev, "unhandled state: %s (%d)\n", uwb_rsv_state_str(new_state), new_state); } } static void uwb_rsv_handle_timeout_work(struct work_struct *work) { struct uwb_rsv *rsv = container_of(work, struct uwb_rsv, handle_timeout_work); struct uwb_rc *rc = rsv->rc; mutex_lock(&rc->rsvs_mutex); uwb_rsv_dump("TO", rsv); switch (rsv->state) { case UWB_RSV_STATE_O_INITIATED: if (rsv->is_multicast) { uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_ESTABLISHED); goto unlock; } break; case UWB_RSV_STATE_O_MOVE_EXPANDING: if (rsv->is_multicast) { uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_MOVE_COMBINING); goto unlock; } break; case UWB_RSV_STATE_O_MOVE_COMBINING: if (rsv->is_multicast) { uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_MOVE_REDUCING); goto unlock; } break; case UWB_RSV_STATE_O_MOVE_REDUCING: if (rsv->is_multicast) { uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_ESTABLISHED); goto unlock; } break; case UWB_RSV_STATE_O_ESTABLISHED: if (rsv->is_multicast) goto unlock; break; case UWB_RSV_STATE_T_EXPANDING_ACCEPTED: /* * The time out could be for the main or of the * companion DRP, assume it's for the companion and * drop that first. A further time out is required to * drop the main. */ uwb_rsv_set_state(rsv, UWB_RSV_STATE_T_ACCEPTED); uwb_drp_avail_release(rsv->rc, &rsv->mv.companion_mas); goto unlock; case UWB_RSV_STATE_NONE: goto unlock; default: break; } uwb_rsv_remove(rsv); unlock: mutex_unlock(&rc->rsvs_mutex); } static struct uwb_rsv *uwb_rsv_alloc(struct uwb_rc *rc) { struct uwb_rsv *rsv; rsv = kzalloc(sizeof(struct uwb_rsv), GFP_KERNEL); if (!rsv) return NULL; INIT_LIST_HEAD(&rsv->rc_node); INIT_LIST_HEAD(&rsv->pal_node); kref_init(&rsv->kref); init_timer(&rsv->timer); rsv->timer.function = uwb_rsv_timer; rsv->timer.data = (unsigned long)rsv; rsv->rc = rc; INIT_WORK(&rsv->handle_timeout_work, uwb_rsv_handle_timeout_work); return rsv; } /** * uwb_rsv_create - allocate and initialize a UWB reservation structure * @rc: the radio controller * @cb: callback to use when the reservation completes or terminates * @pal_priv: data private to the PAL to be passed in the callback * * The callback is called when the state of the reservation changes from: * * - pending to accepted * - pending to denined * - accepted to terminated * - pending to terminated */ struct uwb_rsv *uwb_rsv_create(struct uwb_rc *rc, uwb_rsv_cb_f cb, void *pal_priv) { struct uwb_rsv *rsv; rsv = uwb_rsv_alloc(rc); if (!rsv) return NULL; rsv->callback = cb; rsv->pal_priv = pal_priv; return rsv; } EXPORT_SYMBOL_GPL(uwb_rsv_create); void uwb_rsv_remove(struct uwb_rsv *rsv) { uwb_rsv_dump("RM", rsv); if (rsv->state != UWB_RSV_STATE_NONE) uwb_rsv_set_state(rsv, UWB_RSV_STATE_NONE); if (rsv->needs_release_companion_mas) uwb_drp_avail_release(rsv->rc, &rsv->mv.companion_mas); uwb_drp_avail_release(rsv->rc, &rsv->mas); if (uwb_rsv_is_owner(rsv)) uwb_rsv_put_stream(rsv); uwb_dev_put(rsv->owner); if (rsv->target.type == UWB_RSV_TARGET_DEV) uwb_dev_put(rsv->target.dev); list_del_init(&rsv->rc_node); uwb_rsv_put(rsv); } /** * uwb_rsv_destroy - free a UWB reservation structure * @rsv: the reservation to free * * The reservation must already be terminated. */ void uwb_rsv_destroy(struct uwb_rsv *rsv) { uwb_rsv_put(rsv); } EXPORT_SYMBOL_GPL(uwb_rsv_destroy); /** * usb_rsv_establish - start a reservation establishment * @rsv: the reservation * * The PAL should fill in @rsv's owner, target, type, max_mas, * min_mas, max_interval and is_multicast fields. If the target is a * uwb_dev it must be referenced. * * The reservation's callback will be called when the reservation is * accepted, denied or times out. */ int uwb_rsv_establish(struct uwb_rsv *rsv) { struct uwb_rc *rc = rsv->rc; struct uwb_mas_bm available; struct device *dev = &rc->uwb_dev.dev; int ret; mutex_lock(&rc->rsvs_mutex); ret = uwb_rsv_get_stream(rsv); if (ret) { dev_err(dev, "%s: uwb_rsv_get_stream failed: %d\n", __func__, ret); goto out; } rsv->tiebreaker = prandom_u32() & 1; /* get available mas bitmap */ uwb_drp_available(rc, &available); ret = uwb_rsv_find_best_allocation(rsv, &available, &rsv->mas); if (ret == UWB_RSV_ALLOC_NOT_FOUND) { ret = -EBUSY; uwb_rsv_put_stream(rsv); dev_err(dev, "%s: uwb_rsv_find_best_allocation failed: %d\n", __func__, ret); goto out; } ret = uwb_drp_avail_reserve_pending(rc, &rsv->mas); if (ret != 0) { uwb_rsv_put_stream(rsv); dev_err(dev, "%s: uwb_drp_avail_reserve_pending failed: %d\n", __func__, ret); goto out; } uwb_rsv_get(rsv); list_add_tail(&rsv->rc_node, &rc->reservations); rsv->owner = &rc->uwb_dev; uwb_dev_get(rsv->owner); uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_INITIATED); out: mutex_unlock(&rc->rsvs_mutex); return ret; } EXPORT_SYMBOL_GPL(uwb_rsv_establish); /** * uwb_rsv_modify - modify an already established reservation * @rsv: the reservation to modify * @max_mas: new maximum MAS to reserve * @min_mas: new minimum MAS to reserve * @max_interval: new max_interval to use * * FIXME: implement this once there are PALs that use it. */ int uwb_rsv_modify(struct uwb_rsv *rsv, int max_mas, int min_mas, int max_interval) { return -ENOSYS; } EXPORT_SYMBOL_GPL(uwb_rsv_modify); /* * move an already established reservation (rc->rsvs_mutex must to be * taken when tis function is called) */ int uwb_rsv_try_move(struct uwb_rsv *rsv, struct uwb_mas_bm *available) { struct uwb_rc *rc = rsv->rc; struct uwb_drp_backoff_win *bow = &rc->bow; struct device *dev = &rc->uwb_dev.dev; struct uwb_rsv_move *mv; int ret = 0; if (bow->can_reserve_extra_mases == false) return -EBUSY; mv = &rsv->mv; if (uwb_rsv_find_best_allocation(rsv, available, &mv->final_mas) == UWB_RSV_ALLOC_FOUND) { if (!bitmap_equal(rsv->mas.bm, mv->final_mas.bm, UWB_NUM_MAS)) { /* We want to move the reservation */ bitmap_andnot(mv->companion_mas.bm, mv->final_mas.bm, rsv->mas.bm, UWB_NUM_MAS); uwb_drp_avail_reserve_pending(rc, &mv->companion_mas); uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_MOVE_EXPANDING); } } else { dev_dbg(dev, "new allocation not found\n"); } return ret; } /* It will try to move every reservation in state O_ESTABLISHED giving * to the MAS allocator algorithm an availability that is the real one * plus the allocation already established from the reservation. */ void uwb_rsv_handle_drp_avail_change(struct uwb_rc *rc) { struct uwb_drp_backoff_win *bow = &rc->bow; struct uwb_rsv *rsv; struct uwb_mas_bm mas; if (bow->can_reserve_extra_mases == false) return; list_for_each_entry(rsv, &rc->reservations, rc_node) { if (rsv->state == UWB_RSV_STATE_O_ESTABLISHED || rsv->state == UWB_RSV_STATE_O_TO_BE_MOVED) { uwb_drp_available(rc, &mas); bitmap_or(mas.bm, mas.bm, rsv->mas.bm, UWB_NUM_MAS); uwb_rsv_try_move(rsv, &mas); } } } /** * uwb_rsv_terminate - terminate an established reservation * @rsv: the reservation to terminate * * A reservation is terminated by removing the DRP IE from the beacon, * the other end will consider the reservation to be terminated when * it does not see the DRP IE for at least mMaxLostBeacons. * * If applicable, the reference to the target uwb_dev will be released. */ void uwb_rsv_terminate(struct uwb_rsv *rsv) { struct uwb_rc *rc = rsv->rc; mutex_lock(&rc->rsvs_mutex); if (rsv->state != UWB_RSV_STATE_NONE) uwb_rsv_set_state(rsv, UWB_RSV_STATE_NONE); mutex_unlock(&rc->rsvs_mutex); } EXPORT_SYMBOL_GPL(uwb_rsv_terminate); /** * uwb_rsv_accept - accept a new reservation from a peer * @rsv: the reservation * @cb: call back for reservation changes * @pal_priv: data to be passed in the above call back * * Reservation requests from peers are denied unless a PAL accepts it * by calling this function. * * The PAL call uwb_rsv_destroy() for all accepted reservations before * calling uwb_pal_unregister(). */ void uwb_rsv_accept(struct uwb_rsv *rsv, uwb_rsv_cb_f cb, void *pal_priv) { uwb_rsv_get(rsv); rsv->callback = cb; rsv->pal_priv = pal_priv; rsv->state = UWB_RSV_STATE_T_ACCEPTED; } EXPORT_SYMBOL_GPL(uwb_rsv_accept); /* * Is a received DRP IE for this reservation? */ static bool uwb_rsv_match(struct uwb_rsv *rsv, struct uwb_dev *src, struct uwb_ie_drp *drp_ie) { struct uwb_dev_addr *rsv_src; int stream; stream = uwb_ie_drp_stream_index(drp_ie); if (rsv->stream != stream) return false; switch (rsv->target.type) { case UWB_RSV_TARGET_DEVADDR: return rsv->stream == stream; case UWB_RSV_TARGET_DEV: if (uwb_ie_drp_owner(drp_ie)) rsv_src = &rsv->owner->dev_addr; else rsv_src = &rsv->target.dev->dev_addr; return uwb_dev_addr_cmp(&src->dev_addr, rsv_src) == 0; } return false; } static struct uwb_rsv *uwb_rsv_new_target(struct uwb_rc *rc, struct uwb_dev *src, struct uwb_ie_drp *drp_ie) { struct uwb_rsv *rsv; struct uwb_pal *pal; enum uwb_rsv_state state; rsv = uwb_rsv_alloc(rc); if (!rsv) return NULL; rsv->rc = rc; rsv->owner = src; uwb_dev_get(rsv->owner); rsv->target.type = UWB_RSV_TARGET_DEV; rsv->target.dev = &rc->uwb_dev; uwb_dev_get(&rc->uwb_dev); rsv->type = uwb_ie_drp_type(drp_ie); rsv->stream = uwb_ie_drp_stream_index(drp_ie); uwb_drp_ie_to_bm(&rsv->mas, drp_ie); /* * See if any PALs are interested in this reservation. If not, * deny the request. */ rsv->state = UWB_RSV_STATE_T_DENIED; mutex_lock(&rc->uwb_dev.mutex); list_for_each_entry(pal, &rc->pals, node) { if (pal->new_rsv) pal->new_rsv(pal, rsv); if (rsv->state == UWB_RSV_STATE_T_ACCEPTED) break; } mutex_unlock(&rc->uwb_dev.mutex); list_add_tail(&rsv->rc_node, &rc->reservations); state = rsv->state; rsv->state = UWB_RSV_STATE_NONE; /* FIXME: do something sensible here */ if (state == UWB_RSV_STATE_T_ACCEPTED && uwb_drp_avail_reserve_pending(rc, &rsv->mas) == -EBUSY) { /* FIXME: do something sensible here */ } else { uwb_rsv_set_state(rsv, state); } return rsv; } /** * uwb_rsv_get_usable_mas - get the bitmap of the usable MAS of a reservations * @rsv: the reservation. * @mas: returns the available MAS. * * The usable MAS of a reservation may be less than the negotiated MAS * if alien BPs are present. */ void uwb_rsv_get_usable_mas(struct uwb_rsv *rsv, struct uwb_mas_bm *mas) { bitmap_zero(mas->bm, UWB_NUM_MAS); bitmap_andnot(mas->bm, rsv->mas.bm, rsv->rc->cnflt_alien_bitmap.bm, UWB_NUM_MAS); } EXPORT_SYMBOL_GPL(uwb_rsv_get_usable_mas); /** * uwb_rsv_find - find a reservation for a received DRP IE. * @rc: the radio controller * @src: source of the DRP IE * @drp_ie: the DRP IE * * If the reservation cannot be found and the DRP IE is from a peer * attempting to establish a new reservation, create a new reservation * and add it to the list. */ struct uwb_rsv *uwb_rsv_find(struct uwb_rc *rc, struct uwb_dev *src, struct uwb_ie_drp *drp_ie) { struct uwb_rsv *rsv; list_for_each_entry(rsv, &rc->reservations, rc_node) { if (uwb_rsv_match(rsv, src, drp_ie)) return rsv; } if (uwb_ie_drp_owner(drp_ie)) return uwb_rsv_new_target(rc, src, drp_ie); return NULL; } /* * Go through all the reservations and check for timeouts and (if * necessary) update their DRP IEs. * * FIXME: look at building the SET_DRP_IE command here rather than * having to rescan the list in uwb_rc_send_all_drp_ie(). */ static bool uwb_rsv_update_all(struct uwb_rc *rc) { struct uwb_rsv *rsv, *t; bool ie_updated = false; list_for_each_entry_safe(rsv, t, &rc->reservations, rc_node) { if (!rsv->ie_valid) { uwb_drp_ie_update(rsv); ie_updated = true; } } return ie_updated; } void uwb_rsv_queue_update(struct uwb_rc *rc) { unsigned long delay_us = UWB_MAS_LENGTH_US * UWB_MAS_PER_ZONE; queue_delayed_work(rc->rsv_workq, &rc->rsv_update_work, usecs_to_jiffies(delay_us)); } /** * uwb_rsv_sched_update - schedule an update of the DRP IEs * @rc: the radio controller. * * To improve performance and ensure correctness with [ECMA-368] the * number of SET-DRP-IE commands that are done are limited. * * DRP IEs update come from two sources: DRP events from the hardware * which all occur at the beginning of the superframe ('syncronous' * events) and reservation establishment/termination requests from * PALs or timers ('asynchronous' events). * * A delayed work ensures that all the synchronous events result in * one SET-DRP-IE command. * * Additional logic (the set_drp_ie_pending and rsv_updated_postponed * flags) will prevent an asynchrous event starting a SET-DRP-IE * command if one is currently awaiting a response. * * FIXME: this does leave a window where an asynchrous event can delay * the SET-DRP-IE for a synchronous event by one superframe. */ void uwb_rsv_sched_update(struct uwb_rc *rc) { spin_lock_irq(&rc->rsvs_lock); if (!delayed_work_pending(&rc->rsv_update_work)) { if (rc->set_drp_ie_pending > 0) { rc->set_drp_ie_pending++; goto unlock; } uwb_rsv_queue_update(rc); } unlock: spin_unlock_irq(&rc->rsvs_lock); } /* * Update DRP IEs and, if necessary, the DRP Availability IE and send * the updated IEs to the radio controller. */ static void uwb_rsv_update_work(struct work_struct *work) { struct uwb_rc *rc = container_of(work, struct uwb_rc, rsv_update_work.work); bool ie_updated; mutex_lock(&rc->rsvs_mutex); ie_updated = uwb_rsv_update_all(rc); if (!rc->drp_avail.ie_valid) { uwb_drp_avail_ie_update(rc); ie_updated = true; } if (ie_updated && (rc->set_drp_ie_pending == 0)) uwb_rc_send_all_drp_ie(rc); mutex_unlock(&rc->rsvs_mutex); } static void uwb_rsv_alien_bp_work(struct work_struct *work) { struct uwb_rc *rc = container_of(work, struct uwb_rc, rsv_alien_bp_work.work); struct uwb_rsv *rsv; mutex_lock(&rc->rsvs_mutex); list_for_each_entry(rsv, &rc->reservations, rc_node) { if (rsv->type != UWB_DRP_TYPE_ALIEN_BP) { uwb_rsv_callback(rsv); } } mutex_unlock(&rc->rsvs_mutex); } static void uwb_rsv_timer(unsigned long arg) { struct uwb_rsv *rsv = (struct uwb_rsv *)arg; queue_work(rsv->rc->rsv_workq, &rsv->handle_timeout_work); } /** * uwb_rsv_remove_all - remove all reservations * @rc: the radio controller * * A DRP IE update is not done. */ void uwb_rsv_remove_all(struct uwb_rc *rc) { struct uwb_rsv *rsv, *t; mutex_lock(&rc->rsvs_mutex); list_for_each_entry_safe(rsv, t, &rc->reservations, rc_node) { if (rsv->state != UWB_RSV_STATE_NONE) uwb_rsv_set_state(rsv, UWB_RSV_STATE_NONE); del_timer_sync(&rsv->timer); } /* Cancel any postponed update. */ rc->set_drp_ie_pending = 0; mutex_unlock(&rc->rsvs_mutex); cancel_delayed_work_sync(&rc->rsv_update_work); flush_workqueue(rc->rsv_workq); mutex_lock(&rc->rsvs_mutex); list_for_each_entry_safe(rsv, t, &rc->reservations, rc_node) { uwb_rsv_remove(rsv); } mutex_unlock(&rc->rsvs_mutex); } void uwb_rsv_init(struct uwb_rc *rc) { INIT_LIST_HEAD(&rc->reservations); INIT_LIST_HEAD(&rc->cnflt_alien_list); mutex_init(&rc->rsvs_mutex); spin_lock_init(&rc->rsvs_lock); INIT_DELAYED_WORK(&rc->rsv_update_work, uwb_rsv_update_work); INIT_DELAYED_WORK(&rc->rsv_alien_bp_work, uwb_rsv_alien_bp_work); rc->bow.can_reserve_extra_mases = true; rc->bow.total_expired = 0; rc->bow.window = UWB_DRP_BACKOFF_WIN_MIN >> 1; init_timer(&rc->bow.timer); rc->bow.timer.function = uwb_rsv_backoff_win_timer; rc->bow.timer.data = (unsigned long)&rc->bow; bitmap_complement(rc->uwb_dev.streams, rc->uwb_dev.streams, UWB_NUM_STREAMS); } int uwb_rsv_setup(struct uwb_rc *rc) { char name[16]; snprintf(name, sizeof(name), "%s_rsvd", dev_name(&rc->uwb_dev.dev)); rc->rsv_workq = create_singlethread_workqueue(name); if (rc->rsv_workq == NULL) return -ENOMEM; return 0; } void uwb_rsv_cleanup(struct uwb_rc *rc) { uwb_rsv_remove_all(rc); destroy_workqueue(rc->rsv_workq); }