diff options
Diffstat (limited to 'drivers/uwb/drp.c')
| -rw-r--r-- | drivers/uwb/drp.c | 853 |
1 files changed, 853 insertions, 0 deletions
diff --git a/drivers/uwb/drp.c b/drivers/uwb/drp.c new file mode 100644 index 000000000..625f706b8 --- /dev/null +++ b/drivers/uwb/drp.c @@ -0,0 +1,853 @@ +/* + * 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; + unsigned long flags; + + 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_irqsave(&rc->rsvs_lock, flags); + 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_irqrestore(&rc->rsvs_lock, flags); +} + +/** + * 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); + } +} + +static void uwb_drp_process_target_accepted(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 *mas) +{ + struct uwb_rsv_move *mv = &rsv->mv; + int status; + + status = uwb_ie_drp_status(drp_ie); + + if (rsv->state == UWB_RSV_STATE_T_CONFLICT) { + uwb_rsv_set_state(rsv, UWB_RSV_STATE_T_CONFLICT); + return; + } + + 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); + } + } + + } +} + +/* + * 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: + uwb_drp_process_target_accepted(rc, rsv, drp_evt, drp_ie, &mas); + 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); + } +} + +static void uwb_drp_process_owner_accepted(struct uwb_rsv *rsv, + struct uwb_mas_bm *mas) +{ + struct uwb_rsv_move *mv = &rsv->mv; + + 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; + } +} +/* + * 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; + 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: + uwb_drp_process_owner_accepted(rsv, &mas); + 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(struct timer_list *t) +{ + struct uwb_cnflt_alien *cnflt = from_timer(cnflt, t, timer); + + 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; + unsigned long delay_us = UWB_MAS_LENGTH_US * UWB_MAS_PER_ZONE; + + uwb_drp_ie_to_bm(&mas, drp_ie); + + 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"); + return; + } + + INIT_LIST_HEAD(&cnflt->rc_node); + timer_setup(&cnflt->timer, uwb_cnflt_timer, 0); + + 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; +} |