/* * Ultra Wide Band * Dynamic Reservation Protocol handling * * Copyright (C) 2005-2006 Intel Corporation * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com> * 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/kthread.h> #include <linux/freezer.h> #include <linux/slab.h> #include <linux/delay.h> #include "uwb-internal.h" /* DRP Conflict Actions ([ECMA-368 2nd Edition] 17.4.6) */ enum uwb_drp_conflict_action { /* Reservation is maintained, no action needed */ UWB_DRP_CONFLICT_MANTAIN = 0, /* the device shall not transmit frames in conflicting MASs in * the following superframe. If the device is the reservation * target, it shall also set the Reason Code in its DRP IE to * Conflict in its beacon in the following superframe. */ UWB_DRP_CONFLICT_ACT1, /* the device shall not set the Reservation Status bit to ONE * and shall not transmit frames in conflicting MASs. If the * device is the reservation target, it shall also set the * Reason Code in its DRP IE to Conflict. */ UWB_DRP_CONFLICT_ACT2, /* the device shall not transmit frames in conflicting MASs in * the following superframe. It shall remove the conflicting * MASs from the reservation or set the Reservation Status to * ZERO in its beacon in the following superframe. If the * device is the reservation target, it shall also set the * Reason Code in its DRP IE to Conflict. */ UWB_DRP_CONFLICT_ACT3, }; static void uwb_rc_set_drp_cmd_done(struct uwb_rc *rc, void *arg, struct uwb_rceb *reply, ssize_t reply_size) { struct uwb_rc_evt_set_drp_ie *r = (struct uwb_rc_evt_set_drp_ie *)reply; if (r != NULL) { if (r->bResultCode != UWB_RC_RES_SUCCESS) dev_err(&rc->uwb_dev.dev, "SET-DRP-IE failed: %s (%d)\n", uwb_rc_strerror(r->bResultCode), r->bResultCode); } else dev_err(&rc->uwb_dev.dev, "SET-DRP-IE: timeout\n"); spin_lock_bh(&rc->rsvs_lock); if (rc->set_drp_ie_pending > 1) { rc->set_drp_ie_pending = 0; uwb_rsv_queue_update(rc); } else { rc->set_drp_ie_pending = 0; } spin_unlock_bh(&rc->rsvs_lock); } /** * Construct and send the SET DRP IE * * @rc: UWB Host controller * @returns: >= 0 number of bytes still available in the beacon * < 0 errno code on error. * * See WUSB[8.6.2.7]: The host must set all the DRP IEs that it wants the * device to include in its beacon at the same time. We thus have to * traverse all reservations and include the DRP IEs of all PENDING * and NEGOTIATED reservations in a SET DRP command for transmission. * * A DRP Availability IE is appended. * * rc->rsvs_mutex is held * * FIXME We currently ignore the returned value indicating the remaining space * in beacon. This could be used to deny reservation requests earlier if * determined that they would cause the beacon space to be exceeded. */ int uwb_rc_send_all_drp_ie(struct uwb_rc *rc) { int result; struct uwb_rc_cmd_set_drp_ie *cmd; struct uwb_rsv *rsv; struct uwb_rsv_move *mv; int num_bytes = 0; u8 *IEDataptr; result = -ENOMEM; /* First traverse all reservations to determine memory needed. */ list_for_each_entry(rsv, &rc->reservations, rc_node) { if (rsv->drp_ie != NULL) { num_bytes += rsv->drp_ie->hdr.length + 2; if (uwb_rsv_has_two_drp_ies(rsv) && (rsv->mv.companion_drp_ie != NULL)) { mv = &rsv->mv; num_bytes += mv->companion_drp_ie->hdr.length + 2; } } } num_bytes += sizeof(rc->drp_avail.ie); cmd = kzalloc(sizeof(*cmd) + num_bytes, GFP_KERNEL); if (cmd == NULL) goto error; cmd->rccb.bCommandType = UWB_RC_CET_GENERAL; cmd->rccb.wCommand = cpu_to_le16(UWB_RC_CMD_SET_DRP_IE); cmd->wIELength = num_bytes; IEDataptr = (u8 *)&cmd->IEData[0]; /* FIXME: DRV avail IE is not always needed */ /* put DRP avail IE first */ memcpy(IEDataptr, &rc->drp_avail.ie, sizeof(rc->drp_avail.ie)); IEDataptr += sizeof(struct uwb_ie_drp_avail); /* Next traverse all reservations to place IEs in allocated memory. */ list_for_each_entry(rsv, &rc->reservations, rc_node) { if (rsv->drp_ie != NULL) { memcpy(IEDataptr, rsv->drp_ie, rsv->drp_ie->hdr.length + 2); IEDataptr += rsv->drp_ie->hdr.length + 2; if (uwb_rsv_has_two_drp_ies(rsv) && (rsv->mv.companion_drp_ie != NULL)) { mv = &rsv->mv; memcpy(IEDataptr, mv->companion_drp_ie, mv->companion_drp_ie->hdr.length + 2); IEDataptr += mv->companion_drp_ie->hdr.length + 2; } } } result = uwb_rc_cmd_async(rc, "SET-DRP-IE", &cmd->rccb, sizeof(*cmd) + num_bytes, UWB_RC_CET_GENERAL, UWB_RC_CMD_SET_DRP_IE, uwb_rc_set_drp_cmd_done, NULL); rc->set_drp_ie_pending = 1; kfree(cmd); error: return result; } /* * Evaluate the action to perform using conflict resolution rules * * Return a uwb_drp_conflict_action. */ static int evaluate_conflict_action(struct uwb_ie_drp *ext_drp_ie, int ext_beacon_slot, struct uwb_rsv *rsv, int our_status) { int our_tie_breaker = rsv->tiebreaker; int our_type = rsv->type; int our_beacon_slot = rsv->rc->uwb_dev.beacon_slot; int ext_tie_breaker = uwb_ie_drp_tiebreaker(ext_drp_ie); int ext_status = uwb_ie_drp_status(ext_drp_ie); int ext_type = uwb_ie_drp_type(ext_drp_ie); /* [ECMA-368 2nd Edition] 17.4.6 */ if (ext_type == UWB_DRP_TYPE_PCA && our_type == UWB_DRP_TYPE_PCA) { return UWB_DRP_CONFLICT_MANTAIN; } /* [ECMA-368 2nd Edition] 17.4.6-1 */ if (our_type == UWB_DRP_TYPE_ALIEN_BP) { return UWB_DRP_CONFLICT_MANTAIN; } /* [ECMA-368 2nd Edition] 17.4.6-2 */ if (ext_type == UWB_DRP_TYPE_ALIEN_BP) { /* here we know our_type != UWB_DRP_TYPE_ALIEN_BP */ return UWB_DRP_CONFLICT_ACT1; } /* [ECMA-368 2nd Edition] 17.4.6-3 */ if (our_status == 0 && ext_status == 1) { return UWB_DRP_CONFLICT_ACT2; } /* [ECMA-368 2nd Edition] 17.4.6-4 */ if (our_status == 1 && ext_status == 0) { return UWB_DRP_CONFLICT_MANTAIN; } /* [ECMA-368 2nd Edition] 17.4.6-5a */ if (our_tie_breaker == ext_tie_breaker && our_beacon_slot < ext_beacon_slot) { return UWB_DRP_CONFLICT_MANTAIN; } /* [ECMA-368 2nd Edition] 17.4.6-5b */ if (our_tie_breaker != ext_tie_breaker && our_beacon_slot > ext_beacon_slot) { return UWB_DRP_CONFLICT_MANTAIN; } if (our_status == 0) { if (our_tie_breaker == ext_tie_breaker) { /* [ECMA-368 2nd Edition] 17.4.6-6a */ if (our_beacon_slot > ext_beacon_slot) { return UWB_DRP_CONFLICT_ACT2; } } else { /* [ECMA-368 2nd Edition] 17.4.6-6b */ if (our_beacon_slot < ext_beacon_slot) { return UWB_DRP_CONFLICT_ACT2; } } } else { if (our_tie_breaker == ext_tie_breaker) { /* [ECMA-368 2nd Edition] 17.4.6-7a */ if (our_beacon_slot > ext_beacon_slot) { return UWB_DRP_CONFLICT_ACT3; } } else { /* [ECMA-368 2nd Edition] 17.4.6-7b */ if (our_beacon_slot < ext_beacon_slot) { return UWB_DRP_CONFLICT_ACT3; } } } return UWB_DRP_CONFLICT_MANTAIN; } static void handle_conflict_normal(struct uwb_ie_drp *drp_ie, int ext_beacon_slot, struct uwb_rsv *rsv, struct uwb_mas_bm *conflicting_mas) { struct uwb_rc *rc = rsv->rc; struct uwb_rsv_move *mv = &rsv->mv; struct uwb_drp_backoff_win *bow = &rc->bow; int action; action = evaluate_conflict_action(drp_ie, ext_beacon_slot, rsv, uwb_rsv_status(rsv)); if (uwb_rsv_is_owner(rsv)) { switch(action) { case UWB_DRP_CONFLICT_ACT2: /* try move */ uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_TO_BE_MOVED); if (bow->can_reserve_extra_mases == false) uwb_rsv_backoff_win_increment(rc); break; case UWB_DRP_CONFLICT_ACT3: uwb_rsv_backoff_win_increment(rc); /* drop some mases with reason modified */ /* put in the companion the mases to be dropped */ bitmap_and(mv->companion_mas.bm, rsv->mas.bm, conflicting_mas->bm, UWB_NUM_MAS); uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_MODIFIED); default: break; } } else { switch(action) { case UWB_DRP_CONFLICT_ACT2: case UWB_DRP_CONFLICT_ACT3: uwb_rsv_set_state(rsv, UWB_RSV_STATE_T_CONFLICT); default: break; } } } static void handle_conflict_expanding(struct uwb_ie_drp *drp_ie, int ext_beacon_slot, struct uwb_rsv *rsv, bool companion_only, struct uwb_mas_bm *conflicting_mas) { struct uwb_rc *rc = rsv->rc; struct uwb_drp_backoff_win *bow = &rc->bow; struct uwb_rsv_move *mv = &rsv->mv; int action; if (companion_only) { /* status of companion is 0 at this point */ action = evaluate_conflict_action(drp_ie, ext_beacon_slot, rsv, 0); if (uwb_rsv_is_owner(rsv)) { switch(action) { case UWB_DRP_CONFLICT_ACT2: case UWB_DRP_CONFLICT_ACT3: uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_ESTABLISHED); rsv->needs_release_companion_mas = false; if (bow->can_reserve_extra_mases == false) uwb_rsv_backoff_win_increment(rc); uwb_drp_avail_release(rsv->rc, &rsv->mv.companion_mas); } } else { /* rsv is target */ switch(action) { case UWB_DRP_CONFLICT_ACT2: case UWB_DRP_CONFLICT_ACT3: uwb_rsv_set_state(rsv, UWB_RSV_STATE_T_EXPANDING_CONFLICT); /* send_drp_avail_ie = true; */ } } } else { /* also base part of the reservation is conflicting */ if (uwb_rsv_is_owner(rsv)) { uwb_rsv_backoff_win_increment(rc); /* remove companion part */ uwb_drp_avail_release(rsv->rc, &rsv->mv.companion_mas); /* drop some mases with reason modified */ /* put in the companion the mases to be dropped */ bitmap_andnot(mv->companion_mas.bm, rsv->mas.bm, conflicting_mas->bm, UWB_NUM_MAS); uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_MODIFIED); } else { /* it is a target rsv */ uwb_rsv_set_state(rsv, UWB_RSV_STATE_T_CONFLICT); /* send_drp_avail_ie = true; */ } } } static void uwb_drp_handle_conflict_rsv(struct uwb_rc *rc, struct uwb_rsv *rsv, struct uwb_rc_evt_drp *drp_evt, struct uwb_ie_drp *drp_ie, struct uwb_mas_bm *conflicting_mas) { struct uwb_rsv_move *mv; /* check if the conflicting reservation has two drp_ies */ if (uwb_rsv_has_two_drp_ies(rsv)) { mv = &rsv->mv; if (bitmap_intersects(rsv->mas.bm, conflicting_mas->bm, UWB_NUM_MAS)) { handle_conflict_expanding(drp_ie, drp_evt->beacon_slot_number, rsv, false, conflicting_mas); } else { if (bitmap_intersects(mv->companion_mas.bm, conflicting_mas->bm, UWB_NUM_MAS)) { handle_conflict_expanding(drp_ie, drp_evt->beacon_slot_number, rsv, true, conflicting_mas); } } } else if (bitmap_intersects(rsv->mas.bm, conflicting_mas->bm, UWB_NUM_MAS)) { handle_conflict_normal(drp_ie, drp_evt->beacon_slot_number, rsv, conflicting_mas); } } static void uwb_drp_handle_all_conflict_rsv(struct uwb_rc *rc, struct uwb_rc_evt_drp *drp_evt, struct uwb_ie_drp *drp_ie, struct uwb_mas_bm *conflicting_mas) { struct uwb_rsv *rsv; list_for_each_entry(rsv, &rc->reservations, rc_node) { uwb_drp_handle_conflict_rsv(rc, rsv, drp_evt, drp_ie, conflicting_mas); } } /* * Based on the DRP IE, transition a target reservation to a new * state. */ static void uwb_drp_process_target(struct uwb_rc *rc, struct uwb_rsv *rsv, struct uwb_ie_drp *drp_ie, struct uwb_rc_evt_drp *drp_evt) { struct device *dev = &rc->uwb_dev.dev; struct uwb_rsv_move *mv = &rsv->mv; int status; enum uwb_drp_reason reason_code; struct uwb_mas_bm mas; status = uwb_ie_drp_status(drp_ie); reason_code = uwb_ie_drp_reason_code(drp_ie); uwb_drp_ie_to_bm(&mas, drp_ie); switch (reason_code) { case UWB_DRP_REASON_ACCEPTED: if (rsv->state == UWB_RSV_STATE_T_CONFLICT) { uwb_rsv_set_state(rsv, UWB_RSV_STATE_T_CONFLICT); break; } if (rsv->state == UWB_RSV_STATE_T_EXPANDING_ACCEPTED) { /* drp_ie is companion */ if (!bitmap_equal(rsv->mas.bm, mas.bm, UWB_NUM_MAS)) /* stroke companion */ uwb_rsv_set_state(rsv, UWB_RSV_STATE_T_EXPANDING_ACCEPTED); } else { if (!bitmap_equal(rsv->mas.bm, mas.bm, UWB_NUM_MAS)) { if (uwb_drp_avail_reserve_pending(rc, &mas) == -EBUSY) { /* FIXME: there is a conflict, find * the conflicting reservations and * take a sensible action. Consider * that in drp_ie there is the * "neighbour" */ uwb_drp_handle_all_conflict_rsv(rc, drp_evt, drp_ie, &mas); } else { /* accept the extra reservation */ bitmap_copy(mv->companion_mas.bm, mas.bm, UWB_NUM_MAS); uwb_rsv_set_state(rsv, UWB_RSV_STATE_T_EXPANDING_ACCEPTED); } } else { if (status) { uwb_rsv_set_state(rsv, UWB_RSV_STATE_T_ACCEPTED); } } } break; case UWB_DRP_REASON_MODIFIED: /* check to see if we have already modified the reservation */ if (bitmap_equal(rsv->mas.bm, mas.bm, UWB_NUM_MAS)) { uwb_rsv_set_state(rsv, UWB_RSV_STATE_T_ACCEPTED); break; } /* find if the owner wants to expand or reduce */ if (bitmap_subset(mas.bm, rsv->mas.bm, UWB_NUM_MAS)) { /* owner is reducing */ bitmap_andnot(mv->companion_mas.bm, rsv->mas.bm, mas.bm, UWB_NUM_MAS); uwb_drp_avail_release(rsv->rc, &mv->companion_mas); } bitmap_copy(rsv->mas.bm, mas.bm, UWB_NUM_MAS); uwb_rsv_set_state(rsv, UWB_RSV_STATE_T_RESIZED); break; default: dev_warn(dev, "ignoring invalid DRP IE state (%d/%d)\n", reason_code, status); } } /* * Based on the DRP IE, transition an owner reservation to a new * state. */ static void uwb_drp_process_owner(struct uwb_rc *rc, struct uwb_rsv *rsv, struct uwb_dev *src, struct uwb_ie_drp *drp_ie, struct uwb_rc_evt_drp *drp_evt) { struct device *dev = &rc->uwb_dev.dev; struct uwb_rsv_move *mv = &rsv->mv; int status; enum uwb_drp_reason reason_code; struct uwb_mas_bm mas; status = uwb_ie_drp_status(drp_ie); reason_code = uwb_ie_drp_reason_code(drp_ie); uwb_drp_ie_to_bm(&mas, drp_ie); if (status) { switch (reason_code) { case UWB_DRP_REASON_ACCEPTED: switch (rsv->state) { case UWB_RSV_STATE_O_PENDING: case UWB_RSV_STATE_O_INITIATED: case UWB_RSV_STATE_O_ESTABLISHED: uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_ESTABLISHED); break; case UWB_RSV_STATE_O_MODIFIED: if (bitmap_equal(mas.bm, rsv->mas.bm, UWB_NUM_MAS)) { uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_ESTABLISHED); } else { uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_MODIFIED); } break; case UWB_RSV_STATE_O_MOVE_REDUCING: /* shouldn' t be a problem */ if (bitmap_equal(mas.bm, rsv->mas.bm, UWB_NUM_MAS)) { uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_ESTABLISHED); } else { uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_MOVE_REDUCING); } break; case UWB_RSV_STATE_O_MOVE_EXPANDING: if (bitmap_equal(mas.bm, mv->companion_mas.bm, UWB_NUM_MAS)) { /* Companion reservation accepted */ uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_MOVE_COMBINING); } else { uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_MOVE_EXPANDING); } break; case UWB_RSV_STATE_O_MOVE_COMBINING: if (bitmap_equal(mas.bm, rsv->mas.bm, UWB_NUM_MAS)) uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_MOVE_REDUCING); else uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_MOVE_COMBINING); break; default: break; } break; default: dev_warn(dev, "ignoring invalid DRP IE state (%d/%d)\n", reason_code, status); } } else { switch (reason_code) { case UWB_DRP_REASON_PENDING: uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_PENDING); break; case UWB_DRP_REASON_DENIED: uwb_rsv_set_state(rsv, UWB_RSV_STATE_NONE); break; case UWB_DRP_REASON_CONFLICT: /* resolve the conflict */ bitmap_complement(mas.bm, src->last_availability_bm, UWB_NUM_MAS); uwb_drp_handle_conflict_rsv(rc, rsv, drp_evt, drp_ie, &mas); break; default: dev_warn(dev, "ignoring invalid DRP IE state (%d/%d)\n", reason_code, status); } } } static void uwb_cnflt_alien_stroke_timer(struct uwb_cnflt_alien *cnflt) { unsigned timeout_us = UWB_MAX_LOST_BEACONS * UWB_SUPERFRAME_LENGTH_US; mod_timer(&cnflt->timer, jiffies + usecs_to_jiffies(timeout_us)); } static void uwb_cnflt_update_work(struct work_struct *work) { struct uwb_cnflt_alien *cnflt = container_of(work, struct uwb_cnflt_alien, cnflt_update_work); struct uwb_cnflt_alien *c; struct uwb_rc *rc = cnflt->rc; unsigned long delay_us = UWB_MAS_LENGTH_US * UWB_MAS_PER_ZONE; mutex_lock(&rc->rsvs_mutex); list_del(&cnflt->rc_node); /* update rc global conflicting alien bitmap */ bitmap_zero(rc->cnflt_alien_bitmap.bm, UWB_NUM_MAS); list_for_each_entry(c, &rc->cnflt_alien_list, rc_node) { bitmap_or(rc->cnflt_alien_bitmap.bm, rc->cnflt_alien_bitmap.bm, c->mas.bm, UWB_NUM_MAS); } queue_delayed_work(rc->rsv_workq, &rc->rsv_alien_bp_work, usecs_to_jiffies(delay_us)); kfree(cnflt); mutex_unlock(&rc->rsvs_mutex); } static void uwb_cnflt_timer(unsigned long arg) { struct uwb_cnflt_alien *cnflt = (struct uwb_cnflt_alien *)arg; queue_work(cnflt->rc->rsv_workq, &cnflt->cnflt_update_work); } /* * We have received an DRP_IE of type Alien BP and we need to make * sure we do not transmit in conflicting MASs. */ static void uwb_drp_handle_alien_drp(struct uwb_rc *rc, struct uwb_ie_drp *drp_ie) { struct device *dev = &rc->uwb_dev.dev; struct uwb_mas_bm mas; struct uwb_cnflt_alien *cnflt; char buf[72]; unsigned long delay_us = UWB_MAS_LENGTH_US * UWB_MAS_PER_ZONE; uwb_drp_ie_to_bm(&mas, drp_ie); bitmap_scnprintf(buf, sizeof(buf), mas.bm, UWB_NUM_MAS); list_for_each_entry(cnflt, &rc->cnflt_alien_list, rc_node) { if (bitmap_equal(cnflt->mas.bm, mas.bm, UWB_NUM_MAS)) { /* Existing alien BP reservation conflicting * bitmap, just reset the timer */ uwb_cnflt_alien_stroke_timer(cnflt); return; } } /* New alien BP reservation conflicting bitmap */ /* alloc and initialize new uwb_cnflt_alien */ cnflt = kzalloc(sizeof(struct uwb_cnflt_alien), GFP_KERNEL); if (!cnflt) dev_err(dev, "failed to alloc uwb_cnflt_alien struct\n"); INIT_LIST_HEAD(&cnflt->rc_node); init_timer(&cnflt->timer); cnflt->timer.function = uwb_cnflt_timer; cnflt->timer.data = (unsigned long)cnflt; cnflt->rc = rc; INIT_WORK(&cnflt->cnflt_update_work, uwb_cnflt_update_work); bitmap_copy(cnflt->mas.bm, mas.bm, UWB_NUM_MAS); list_add_tail(&cnflt->rc_node, &rc->cnflt_alien_list); /* update rc global conflicting alien bitmap */ bitmap_or(rc->cnflt_alien_bitmap.bm, rc->cnflt_alien_bitmap.bm, mas.bm, UWB_NUM_MAS); queue_delayed_work(rc->rsv_workq, &rc->rsv_alien_bp_work, usecs_to_jiffies(delay_us)); /* start the timer */ uwb_cnflt_alien_stroke_timer(cnflt); } static void uwb_drp_process_not_involved(struct uwb_rc *rc, struct uwb_rc_evt_drp *drp_evt, struct uwb_ie_drp *drp_ie) { struct uwb_mas_bm mas; uwb_drp_ie_to_bm(&mas, drp_ie); uwb_drp_handle_all_conflict_rsv(rc, drp_evt, drp_ie, &mas); } static void uwb_drp_process_involved(struct uwb_rc *rc, struct uwb_dev *src, struct uwb_rc_evt_drp *drp_evt, struct uwb_ie_drp *drp_ie) { struct uwb_rsv *rsv; rsv = uwb_rsv_find(rc, src, drp_ie); if (!rsv) { /* * No reservation? It's either for a recently * terminated reservation; or the DRP IE couldn't be * processed (e.g., an invalid IE or out of memory). */ return; } /* * Do nothing with DRP IEs for reservations that have been * terminated. */ if (rsv->state == UWB_RSV_STATE_NONE) { uwb_rsv_set_state(rsv, UWB_RSV_STATE_NONE); return; } if (uwb_ie_drp_owner(drp_ie)) uwb_drp_process_target(rc, rsv, drp_ie, drp_evt); else uwb_drp_process_owner(rc, rsv, src, drp_ie, drp_evt); } static bool uwb_drp_involves_us(struct uwb_rc *rc, struct uwb_ie_drp *drp_ie) { return uwb_dev_addr_cmp(&rc->uwb_dev.dev_addr, &drp_ie->dev_addr) == 0; } /* * Process a received DRP IE. */ static void uwb_drp_process(struct uwb_rc *rc, struct uwb_rc_evt_drp *drp_evt, struct uwb_dev *src, struct uwb_ie_drp *drp_ie) { if (uwb_ie_drp_type(drp_ie) == UWB_DRP_TYPE_ALIEN_BP) uwb_drp_handle_alien_drp(rc, drp_ie); else if (uwb_drp_involves_us(rc, drp_ie)) uwb_drp_process_involved(rc, src, drp_evt, drp_ie); else uwb_drp_process_not_involved(rc, drp_evt, drp_ie); } /* * Process a received DRP Availability IE */ static void uwb_drp_availability_process(struct uwb_rc *rc, struct uwb_dev *src, struct uwb_ie_drp_avail *drp_availability_ie) { bitmap_copy(src->last_availability_bm, drp_availability_ie->bmp, UWB_NUM_MAS); } /* * Process all the DRP IEs (both DRP IEs and the DRP Availability IE) * from a device. */ static void uwb_drp_process_all(struct uwb_rc *rc, struct uwb_rc_evt_drp *drp_evt, size_t ielen, struct uwb_dev *src_dev) { struct device *dev = &rc->uwb_dev.dev; struct uwb_ie_hdr *ie_hdr; void *ptr; ptr = drp_evt->ie_data; for (;;) { ie_hdr = uwb_ie_next(&ptr, &ielen); if (!ie_hdr) break; switch (ie_hdr->element_id) { case UWB_IE_DRP_AVAILABILITY: uwb_drp_availability_process(rc, src_dev, (struct uwb_ie_drp_avail *)ie_hdr); break; case UWB_IE_DRP: uwb_drp_process(rc, drp_evt, src_dev, (struct uwb_ie_drp *)ie_hdr); break; default: dev_warn(dev, "unexpected IE in DRP notification\n"); break; } } if (ielen > 0) dev_warn(dev, "%d octets remaining in DRP notification\n", (int)ielen); } /** * uwbd_evt_handle_rc_drp - handle a DRP_IE event * @evt: the DRP_IE event from the radio controller * * This processes DRP notifications from the radio controller, either * initiating a new reservation or transitioning an existing * reservation into a different state. * * DRP notifications can occur for three different reasons: * * - UWB_DRP_NOTIF_DRP_IE_RECVD: one or more DRP IEs with the RC as * the target or source have been received. * * These DRP IEs could be new or for an existing reservation. * * If the DRP IE for an existing reservation ceases to be to * received for at least mMaxLostBeacons, the reservation should be * considered to be terminated. Note that the TERMINATE reason (see * below) may not always be signalled (e.g., the remote device has * two or more reservations established with the RC). * * - UWB_DRP_NOTIF_CONFLICT: DRP IEs from any device in the beacon * group conflict with the RC's reservations. * * - UWB_DRP_NOTIF_TERMINATE: DRP IEs are no longer being received * from a device (i.e., it's terminated all reservations). * * Only the software state of the reservations is changed; the setting * of the radio controller's DRP IEs is done after all the events in * an event buffer are processed. This saves waiting multiple times * for the SET_DRP_IE command to complete. */ int uwbd_evt_handle_rc_drp(struct uwb_event *evt) { struct device *dev = &evt->rc->uwb_dev.dev; struct uwb_rc *rc = evt->rc; struct uwb_rc_evt_drp *drp_evt; size_t ielength, bytes_left; struct uwb_dev_addr src_addr; struct uwb_dev *src_dev; /* Is there enough data to decode the event (and any IEs in its payload)? */ if (evt->notif.size < sizeof(*drp_evt)) { dev_err(dev, "DRP event: Not enough data to decode event " "[%zu bytes left, %zu needed]\n", evt->notif.size, sizeof(*drp_evt)); return 0; } bytes_left = evt->notif.size - sizeof(*drp_evt); drp_evt = container_of(evt->notif.rceb, struct uwb_rc_evt_drp, rceb); ielength = le16_to_cpu(drp_evt->ie_length); if (bytes_left != ielength) { dev_err(dev, "DRP event: Not enough data in payload [%zu" "bytes left, %zu declared in the event]\n", bytes_left, ielength); return 0; } memcpy(src_addr.data, &drp_evt->src_addr, sizeof(src_addr)); src_dev = uwb_dev_get_by_devaddr(rc, &src_addr); if (!src_dev) { /* * A DRP notification from an unrecognized device. * * This is probably from a WUSB device that doesn't * have an EUI-48 and therefore doesn't show up in the * UWB device database. It's safe to simply ignore * these. */ return 0; } mutex_lock(&rc->rsvs_mutex); /* We do not distinguish from the reason */ uwb_drp_process_all(rc, drp_evt, ielength, src_dev); mutex_unlock(&rc->rsvs_mutex); uwb_dev_put(src_dev); return 0; }