diff options
Diffstat (limited to 'drivers/uwb')
| -rw-r--r-- | drivers/uwb/drp-avail.c | 288 | ||||
| -rw-r--r-- | drivers/uwb/drp-ie.c | 232 | ||||
| -rw-r--r-- | drivers/uwb/drp.c | 461 | ||||
| -rw-r--r-- | drivers/uwb/rsv.c | 680 |
4 files changed, 1661 insertions, 0 deletions
diff --git a/drivers/uwb/drp-avail.c b/drivers/uwb/drp-avail.c new file mode 100644 index 0000000..3febd85 --- /dev/null +++ b/drivers/uwb/drp-avail.c @@ -0,0 +1,288 @@ +/* + * Ultra Wide Band + * DRP availability management + * + * Copyright (C) 2005-2006 Intel Corporation + * Reinette Chatre <reinette.chatre@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/>. + * + * + * Manage DRP Availability (the MAS available for DRP + * reservations). Thus: + * + * - Handle DRP Availability Change notifications + * + * - Allow the reservation manager to indicate MAS reserved/released + * by local (owned by/targeted at the radio controller) + * reservations. + * + * - Based on the two sources above, generate a DRP Availability IE to + * be included in the beacon. + * + * See also the documentation for struct uwb_drp_avail. + */ + +#include <linux/errno.h> +#include <linux/module.h> +#include <linux/device.h> +#include <linux/bitmap.h> +#include "uwb-internal.h" + +/** + * uwb_drp_avail_init - initialize an RC's MAS availability + * + * All MAS are available initially. The RC will inform use which + * slots are used for the BP (it may change in size). + */ +void uwb_drp_avail_init(struct uwb_rc *rc) +{ + bitmap_fill(rc->drp_avail.global, UWB_NUM_MAS); + bitmap_fill(rc->drp_avail.local, UWB_NUM_MAS); + bitmap_fill(rc->drp_avail.pending, UWB_NUM_MAS); +} + +/* + * Determine MAS available for new local reservations. + * + * avail = global & local & pending + */ +static void uwb_drp_available(struct uwb_rc *rc, struct uwb_mas_bm *avail) +{ + bitmap_and(avail->bm, rc->drp_avail.global, rc->drp_avail.local, UWB_NUM_MAS); + bitmap_and(avail->bm, avail->bm, rc->drp_avail.pending, UWB_NUM_MAS); +} + +/** + * uwb_drp_avail_reserve_pending - reserve MAS for a new reservation + * @rc: the radio controller + * @mas: the MAS to reserve + * + * Returns 0 on success, or -EBUSY if the MAS requested aren't available. + */ +int uwb_drp_avail_reserve_pending(struct uwb_rc *rc, struct uwb_mas_bm *mas) +{ + struct uwb_mas_bm avail; + + uwb_drp_available(rc, &avail); + if (!bitmap_subset(mas->bm, avail.bm, UWB_NUM_MAS)) + return -EBUSY; + + bitmap_andnot(rc->drp_avail.pending, rc->drp_avail.pending, mas->bm, UWB_NUM_MAS); + return 0; +} + +/** + * uwb_drp_avail_reserve - reserve MAS for an established reservation + * @rc: the radio controller + * @mas: the MAS to reserve + */ +void uwb_drp_avail_reserve(struct uwb_rc *rc, struct uwb_mas_bm *mas) +{ + bitmap_or(rc->drp_avail.pending, rc->drp_avail.pending, mas->bm, UWB_NUM_MAS); + bitmap_andnot(rc->drp_avail.local, rc->drp_avail.local, mas->bm, UWB_NUM_MAS); + rc->drp_avail.ie_valid = false; +} + +/** + * uwb_drp_avail_release - release MAS from a pending or established reservation + * @rc: the radio controller + * @mas: the MAS to release + */ +void uwb_drp_avail_release(struct uwb_rc *rc, struct uwb_mas_bm *mas) +{ + bitmap_or(rc->drp_avail.local, rc->drp_avail.local, mas->bm, UWB_NUM_MAS); + bitmap_or(rc->drp_avail.pending, rc->drp_avail.pending, mas->bm, UWB_NUM_MAS); + rc->drp_avail.ie_valid = false; +} + +/** + * uwb_drp_avail_ie_update - update the DRP Availability IE + * @rc: the radio controller + * + * avail = global & local + */ +void uwb_drp_avail_ie_update(struct uwb_rc *rc) +{ + struct uwb_mas_bm avail; + + bitmap_and(avail.bm, rc->drp_avail.global, rc->drp_avail.local, UWB_NUM_MAS); + + rc->drp_avail.ie.hdr.element_id = UWB_IE_DRP_AVAILABILITY; + rc->drp_avail.ie.hdr.length = UWB_NUM_MAS / 8; + uwb_mas_bm_copy_le(rc->drp_avail.ie.bmp, &avail); + rc->drp_avail.ie_valid = true; +} + +/** + * Create an unsigned long from a buffer containing a byte stream. + * + * @array: pointer to buffer + * @itr: index of buffer from where we start + * @len: the buffer's remaining size may not be exact multiple of + * sizeof(unsigned long), @len is the length of buffer that needs + * to be converted. This will be sizeof(unsigned long) or smaller + * (BUG if not). If it is smaller then we will pad the remaining + * space of the result with zeroes. + */ +static +unsigned long get_val(u8 *array, size_t itr, size_t len) +{ + unsigned long val = 0; + size_t top = itr + len; + + BUG_ON(len > sizeof(val)); + + while (itr < top) { + val <<= 8; + val |= array[top - 1]; + top--; + } + val <<= 8 * (sizeof(val) - len); /* padding */ + return val; +} + +/** + * Initialize bitmap from data buffer. + * + * The bitmap to be converted could come from a IE, for example a + * DRP Availability IE. + * From ECMA-368 1.0 [16.8.7]: " + * octets: 1 1 N * (0 to 32) + * Element ID Length (=N) DRP Availability Bitmap + * + * The DRP Availability Bitmap field is up to 256 bits long, one + * bit for each MAS in the superframe, where the least-significant + * bit of the field corresponds to the first MAS in the superframe + * and successive bits correspond to successive MASs." + * + * The DRP Availability bitmap is in octets from 0 to 32, so octet + * 32 contains bits for MAS 1-8, etc. If the bitmap is smaller than 32 + * octets, the bits in octets not included at the end of the bitmap are + * treated as zero. In this case (when the bitmap is smaller than 32 + * octets) the MAS represented range from MAS 1 to MAS (size of bitmap) + * with the last octet still containing bits for MAS 1-8, etc. + * + * For example: + * F00F0102 03040506 0708090A 0B0C0D0E 0F010203 + * ^^^^ + * |||| + * |||| + * |||\LSB of byte is MAS 9 + * ||\MSB of byte is MAS 16 + * |\LSB of first byte is MAS 1 + * \ MSB of byte is MAS 8 + * + * An example of this encoding can be found in ECMA-368 Annex-D [Table D.11] + * + * The resulting bitmap will have the following mapping: + * bit position 0 == MAS 1 + * bit position 1 == MAS 2 + * ... + * bit position (UWB_NUM_MAS - 1) == MAS UWB_NUM_MAS + * + * @bmp_itr: pointer to bitmap (can be declared with DECLARE_BITMAP) + * @buffer: pointer to buffer containing bitmap data in big endian + * format (MSB first) + * @buffer_size:number of bytes with which bitmap should be initialized + */ +static +void buffer_to_bmp(unsigned long *bmp_itr, void *_buffer, + size_t buffer_size) +{ + u8 *buffer = _buffer; + size_t itr, len; + unsigned long val; + + itr = 0; + while (itr < buffer_size) { + len = buffer_size - itr >= sizeof(val) ? + sizeof(val) : buffer_size - itr; + val = get_val(buffer, itr, len); + bmp_itr[itr / sizeof(val)] = val; + itr += sizeof(val); + } +} + + +/** + * Extract DRP Availability bitmap from the notification. + * + * The notification that comes in contains a bitmap of (UWB_NUM_MAS / 8) bytes + * We convert that to our internal representation. + */ +static +int uwbd_evt_get_drp_avail(struct uwb_event *evt, unsigned long *bmp) +{ + struct device *dev = &evt->rc->uwb_dev.dev; + struct uwb_rc_evt_drp_avail *drp_evt; + int result = -EINVAL; + + /* Is there enough data to decode the event? */ + if (evt->notif.size < sizeof(*drp_evt)) { + dev_err(dev, "DRP Availability Change: Not enough " + "data to decode event [%zu bytes, %zu " + "needed]\n", evt->notif.size, sizeof(*drp_evt)); + goto error; + } + drp_evt = container_of(evt->notif.rceb, struct uwb_rc_evt_drp_avail, rceb); + buffer_to_bmp(bmp, drp_evt->bmp, UWB_NUM_MAS/8); + result = 0; +error: + return result; +} + + +/** + * Process an incoming DRP Availability notification. + * + * @evt: Event information (packs the actual event data, which + * radio controller it came to, etc). + * + * @returns: 0 on success (so uwbd() frees the event buffer), < 0 + * on error. + * + * According to ECMA-368 1.0 [16.8.7], bits set to ONE indicate that + * the MAS slot is available, bits set to ZERO indicate that the slot + * is busy. + * + * So we clear available slots, we set used slots :) + * + * The notification only marks non-availability based on the BP and + * received DRP IEs that are not for this radio controller. A copy of + * this bitmap is needed to generate the real availability (which + * includes local and pending reservations). + * + * The DRP Availability IE that this radio controller emits will need + * to be updated. + */ +int uwbd_evt_handle_rc_drp_avail(struct uwb_event *evt) +{ + int result; + struct uwb_rc *rc = evt->rc; + DECLARE_BITMAP(bmp, UWB_NUM_MAS); + + result = uwbd_evt_get_drp_avail(evt, bmp); + if (result < 0) + return result; + + mutex_lock(&rc->rsvs_mutex); + bitmap_copy(rc->drp_avail.global, bmp, UWB_NUM_MAS); + rc->drp_avail.ie_valid = false; + mutex_unlock(&rc->rsvs_mutex); + + uwb_rsv_sched_update(rc); + + return 0; +} diff --git a/drivers/uwb/drp-ie.c b/drivers/uwb/drp-ie.c new file mode 100644 index 0000000..882724c --- /dev/null +++ b/drivers/uwb/drp-ie.c @@ -0,0 +1,232 @@ +/* + * UWB DRP IE management. + * + * Copyright (C) 2005-2006 Intel Corporation + * 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/version.h> +#include <linux/kernel.h> +#include <linux/random.h> +#include <linux/uwb.h> + +#include "uwb-internal.h" + +/* + * Allocate a DRP IE. + * + * To save having to free/allocate a DRP IE when its MAS changes, + * enough memory is allocated for the maxiumum number of DRP + * allocation fields. This gives an overhead per reservation of up to + * (UWB_NUM_ZONES - 1) * 4 = 60 octets. + */ +static struct uwb_ie_drp *uwb_drp_ie_alloc(void) +{ + struct uwb_ie_drp *drp_ie; + unsigned tiebreaker; + + drp_ie = kzalloc(sizeof(struct uwb_ie_drp) + + UWB_NUM_ZONES * sizeof(struct uwb_drp_alloc), + GFP_KERNEL); + if (drp_ie) { + drp_ie->hdr.element_id = UWB_IE_DRP; + + get_random_bytes(&tiebreaker, sizeof(unsigned)); + uwb_ie_drp_set_tiebreaker(drp_ie, tiebreaker & 1); + } + return drp_ie; +} + + +/* + * Fill a DRP IE's allocation fields from a MAS bitmap. + */ +static void uwb_drp_ie_from_bm(struct uwb_ie_drp *drp_ie, + struct uwb_mas_bm *mas) +{ + int z, i, num_fields = 0, next = 0; + struct uwb_drp_alloc *zones; + __le16 current_bmp; + DECLARE_BITMAP(tmp_bmp, UWB_NUM_MAS); + DECLARE_BITMAP(tmp_mas_bm, UWB_MAS_PER_ZONE); + + zones = drp_ie->allocs; + + bitmap_copy(tmp_bmp, mas->bm, UWB_NUM_MAS); + + /* Determine unique MAS bitmaps in zones from bitmap. */ + for (z = 0; z < UWB_NUM_ZONES; z++) { + bitmap_copy(tmp_mas_bm, tmp_bmp, UWB_MAS_PER_ZONE); + if (bitmap_weight(tmp_mas_bm, UWB_MAS_PER_ZONE) > 0) { + bool found = false; + current_bmp = (__le16) *tmp_mas_bm; + for (i = 0; i < next; i++) { + if (current_bmp == zones[i].mas_bm) { + zones[i].zone_bm |= 1 << z; + found = true; + break; + } + } + if (!found) { + num_fields++; + zones[next].zone_bm = 1 << z; + zones[next].mas_bm = current_bmp; + next++; + } + } + bitmap_shift_right(tmp_bmp, tmp_bmp, UWB_MAS_PER_ZONE, UWB_NUM_MAS); + } + + /* Store in format ready for transmission (le16). */ + for (i = 0; i < num_fields; i++) { + drp_ie->allocs[i].zone_bm = cpu_to_le16(zones[i].zone_bm); + drp_ie->allocs[i].mas_bm = cpu_to_le16(zones[i].mas_bm); + } + + drp_ie->hdr.length = sizeof(struct uwb_ie_drp) - sizeof(struct uwb_ie_hdr) + + num_fields * sizeof(struct uwb_drp_alloc); +} + +/** + * uwb_drp_ie_update - update a reservation's DRP IE + * @rsv: the reservation + */ +int uwb_drp_ie_update(struct uwb_rsv *rsv) +{ + struct device *dev = &rsv->rc->uwb_dev.dev; + struct uwb_ie_drp *drp_ie; + int reason_code, status; + + switch (rsv->state) { + case UWB_RSV_STATE_NONE: + kfree(rsv->drp_ie); + rsv->drp_ie = NULL; + return 0; + case UWB_RSV_STATE_O_INITIATED: + reason_code = UWB_DRP_REASON_ACCEPTED; + status = 0; + break; + case UWB_RSV_STATE_O_PENDING: + reason_code = UWB_DRP_REASON_ACCEPTED; + status = 0; + break; + case UWB_RSV_STATE_O_MODIFIED: + reason_code = UWB_DRP_REASON_MODIFIED; + status = 1; + break; + case UWB_RSV_STATE_O_ESTABLISHED: + reason_code = UWB_DRP_REASON_ACCEPTED; + status = 1; + break; + case UWB_RSV_STATE_T_ACCEPTED: + reason_code = UWB_DRP_REASON_ACCEPTED; + status = 1; + break; + case UWB_RSV_STATE_T_DENIED: + reason_code = UWB_DRP_REASON_DENIED; + status = 0; + break; + default: + dev_dbg(dev, "rsv with unhandled state (%d)\n", rsv->state); + return -EINVAL; + } + + if (rsv->drp_ie == NULL) { + rsv->drp_ie = uwb_drp_ie_alloc(); + if (rsv->drp_ie == NULL) + return -ENOMEM; + } + drp_ie = rsv->drp_ie; + + uwb_ie_drp_set_owner(drp_ie, uwb_rsv_is_owner(rsv)); + uwb_ie_drp_set_status(drp_ie, status); + uwb_ie_drp_set_reason_code(drp_ie, reason_code); + uwb_ie_drp_set_stream_index(drp_ie, rsv->stream); + uwb_ie_drp_set_type(drp_ie, rsv->type); + + if (uwb_rsv_is_owner(rsv)) { + switch (rsv->target.type) { + case UWB_RSV_TARGET_DEV: + drp_ie->dev_addr = rsv->target.dev->dev_addr; + break; + case UWB_RSV_TARGET_DEVADDR: + drp_ie->dev_addr = rsv->target.devaddr; + break; + } + } else + drp_ie->dev_addr = rsv->owner->dev_addr; + + uwb_drp_ie_from_bm(drp_ie, &rsv->mas); + + rsv->ie_valid = true; + return 0; +} + +/* + * Set MAS bits from given MAS bitmap in a single zone of large bitmap. + * + * We are given a zone id and the MAS bitmap of bits that need to be set in + * this zone. Note that this zone may already have bits set and this only + * adds settings - we cannot simply assign the MAS bitmap contents to the + * zone contents. We iterate over the the bits (MAS) in the zone and set the + * bits that are set in the given MAS bitmap. + */ +static +void uwb_drp_ie_single_zone_to_bm(struct uwb_mas_bm *bm, u8 zone, u16 mas_bm) +{ + int mas; + u16 mas_mask; + + for (mas = 0; mas < UWB_MAS_PER_ZONE; mas++) { + mas_mask = 1 << mas; + if (mas_bm & mas_mask) + set_bit(zone * UWB_NUM_ZONES + mas, bm->bm); + } +} + +/** + * uwb_drp_ie_zones_to_bm - convert DRP allocation fields to a bitmap + * @mas: MAS bitmap that will be populated to correspond to the + * allocation fields in the DRP IE + * @drp_ie: the DRP IE that contains the allocation fields. + * + * The input format is an array of MAS allocation fields (16 bit Zone + * bitmap, 16 bit MAS bitmap) as described in [ECMA-368] section + * 16.8.6. The output is a full 256 bit MAS bitmap. + * + * We go over all the allocation fields, for each allocation field we + * know which zones are impacted. We iterate over all the zones + * impacted and call a function that will set the correct MAS bits in + * each zone. + */ +void uwb_drp_ie_to_bm(struct uwb_mas_bm *bm, const struct uwb_ie_drp *drp_ie) +{ + int numallocs = (drp_ie->hdr.length - 4) / 4; + const struct uwb_drp_alloc *alloc; + int cnt; + u16 zone_bm, mas_bm; + u8 zone; + u16 zone_mask; + + for (cnt = 0; cnt < numallocs; cnt++) { + alloc = &drp_ie->allocs[cnt]; + zone_bm = le16_to_cpu(alloc->zone_bm); + mas_bm = le16_to_cpu(alloc->mas_bm); + for (zone = 0; zone < UWB_NUM_ZONES; zone++) { + zone_mask = 1 << zone; + if (zone_bm & zone_mask) + uwb_drp_ie_single_zone_to_bm(bm, zone, mas_bm); + } + } +} diff --git a/drivers/uwb/drp.c b/drivers/uwb/drp.c new file mode 100644 index 0000000..c0b1e5e --- /dev/null +++ b/drivers/uwb/drp.c @@ -0,0 +1,461 @@ +/* + * 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/delay.h> +#include "uwb-internal.h" + +/** + * 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->uwb_dev.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. + */ +static +int uwb_rc_gen_send_drp_ie(struct uwb_rc *rc) +{ + int result; + struct device *dev = &rc->uwb_dev.dev; + struct uwb_rc_cmd_set_drp_ie *cmd; + struct uwb_rc_evt_set_drp_ie reply; + struct uwb_rsv *rsv; + 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; + } + 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]; + + /* 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; + } + } + memcpy(IEDataptr, &rc->drp_avail.ie, sizeof(rc->drp_avail.ie)); + + reply.rceb.bEventType = UWB_RC_CET_GENERAL; + reply.rceb.wEvent = UWB_RC_CMD_SET_DRP_IE; + result = uwb_rc_cmd(rc, "SET-DRP-IE", &cmd->rccb, + sizeof(*cmd) + num_bytes, &reply.rceb, + sizeof(reply)); + if (result < 0) + goto error_cmd; + result = le16_to_cpu(reply.wRemainingSpace); + if (reply.bResultCode != UWB_RC_RES_SUCCESS) { + dev_err(&rc->uwb_dev.dev, "SET-DRP-IE: command execution " + "failed: %s (%d). RemainingSpace in beacon " + "= %d\n", uwb_rc_strerror(reply.bResultCode), + reply.bResultCode, result); + result = -EIO; + } else { + dev_dbg(dev, "SET-DRP-IE sent. RemainingSpace in beacon " + "= %d.\n", result); + result = 0; + } +error_cmd: + kfree(cmd); +error: + return result; + +} +/** + * Send all DRP IEs associated with this host + * + * @returns: >= 0 number of bytes still available in the beacon + * < 0 errno code on error. + * + * As per the protocol we obtain the host controller device lock to access + * bandwidth structures. + */ +int uwb_rc_send_all_drp_ie(struct uwb_rc *rc) +{ + int result; + + mutex_lock(&rc->uwb_dev.mutex); + result = uwb_rc_gen_send_drp_ie(rc); + mutex_unlock(&rc->uwb_dev.mutex); + return result; +} + +void uwb_drp_handle_timeout(struct uwb_rsv *rsv) +{ + struct device *dev = &rsv->rc->uwb_dev.dev; + + dev_dbg(dev, "reservation timeout in state %s (%d)\n", + uwb_rsv_state_str(rsv->state), rsv->state); + + switch (rsv->state) { + case UWB_RSV_STATE_O_INITIATED: + if (rsv->is_multicast) { + uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_ESTABLISHED); + return; + } + break; + case UWB_RSV_STATE_O_ESTABLISHED: + if (rsv->is_multicast) + return; + break; + default: + break; + } + uwb_rsv_remove(rsv); +} + +/* + * 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 device *dev = &rc->uwb_dev.dev; + int status; + enum uwb_drp_reason reason_code; + + status = uwb_ie_drp_status(drp_ie); + reason_code = uwb_ie_drp_reason_code(drp_ie); + + if (status) { + switch (reason_code) { + case UWB_DRP_REASON_ACCEPTED: + uwb_rsv_set_state(rsv, UWB_RSV_STATE_T_ACCEPTED); + break; + case UWB_DRP_REASON_MODIFIED: + dev_err(dev, "FIXME: unhandled reason code (%d/%d)\n", + reason_code, status); + break; + default: + dev_warn(dev, "ignoring invalid DRP IE state (%d/%d)\n", + reason_code, status); + } + } else { + switch (reason_code) { + case UWB_DRP_REASON_ACCEPTED: + /* New reservations are handled in uwb_rsv_find(). */ + break; + case UWB_DRP_REASON_DENIED: + uwb_rsv_set_state(rsv, UWB_RSV_STATE_NONE); + break; + case UWB_DRP_REASON_CONFLICT: + case UWB_DRP_REASON_MODIFIED: + dev_err(dev, "FIXME: unhandled reason code (%d/%d)\n", + reason_code, status); + 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_ie_drp *drp_ie) +{ + struct device *dev = &rc->uwb_dev.dev; + int status; + enum uwb_drp_reason reason_code; + + status = uwb_ie_drp_status(drp_ie); + reason_code = uwb_ie_drp_reason_code(drp_ie); + + if (status) { + switch (reason_code) { + case UWB_DRP_REASON_ACCEPTED: + uwb_rsv_set_state(rsv, UWB_RSV_STATE_O_ESTABLISHED); + break; + case UWB_DRP_REASON_MODIFIED: + dev_err(dev, "FIXME: unhandled reason code (%d/%d)\n", + reason_code, status); + 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: + case UWB_DRP_REASON_MODIFIED: + dev_err(dev, "FIXME: unhandled reason code (%d/%d)\n", + reason_code, status); + break; + default: + dev_warn(dev, "ignoring invalid DRP IE state (%d/%d)\n", + reason_code, status); + } + } +} + +/* + * Process a received DRP IE, it's either for a reservation owned by + * the RC or targeted at it (or it's for a WUSB cluster reservation). + */ +static void uwb_drp_process(struct uwb_rc *rc, struct uwb_dev *src, + 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); + else + uwb_drp_process_owner(rc, rsv, drp_ie); +} + + +/* + * 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: + /* FIXME: does something need to be done with this? */ + break; + case UWB_IE_DRP: + uwb_drp_process(rc, 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); +} + + +/* + * Go through all the DRP IEs and find the ones that conflict with our + * reservations. + * + * FIXME: must resolve the conflict according the the rules in + * [ECMA-368]. + */ +static +void uwb_drp_process_conflict_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; + struct uwb_ie_drp *drp_ie; + void *ptr; + + ptr = drp_evt->ie_data; + for (;;) { + ie_hdr = uwb_ie_next(&ptr, &ielen); + if (!ie_hdr) + break; + + drp_ie = container_of(ie_hdr, struct uwb_ie_drp, hdr); + + /* FIXME: check if this DRP IE conflicts. */ + } + + if (ielen > 0) + dev_warn(dev, "%d octets remaining in DRP notification\n", + (int)ielen); +} + + +/* + * Terminate all reservations owned by, or targeted at, 'uwb_dev'. + */ +static void uwb_drp_terminate_all(struct uwb_rc *rc, struct uwb_dev *uwb_dev) +{ + struct uwb_rsv *rsv; + + list_for_each_entry(rsv, &rc->reservations, rc_node) { + if (rsv->owner == uwb_dev + || (rsv->target.type == UWB_RSV_TARGET_DEV && rsv->target.dev == uwb_dev)) + uwb_rsv_remove(rsv); + } +} + + +/** + * 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 recieved. + * + * These DRP IEs could be new or for an existing reservation. + * + * If the DRP IE for an existing reservation ceases to be to + * recieved 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; + int reason; + + /* 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); + + reason = uwb_rc_evt_drp_reason(drp_evt); + + switch (reason) { + case UWB_DRP_NOTIF_DRP_IE_RCVD: + uwb_drp_process_all(rc, drp_evt, ielength, src_dev); + break; + case UWB_DRP_NOTIF_CONFLICT: + uwb_drp_process_conflict_all(rc, drp_evt, ielength, src_dev); + break; + case UWB_DRP_NOTIF_TERMINATE: + uwb_drp_terminate_all(rc, src_dev); + break; + default: + dev_warn(dev, "ignored DRP event with reason code: %d\n", reason); + break; + } + + mutex_unlock(&rc->rsvs_mutex); + + uwb_dev_put(src_dev); + return 0; +} diff --git a/drivers/uwb/rsv.c b/drivers/uwb/rsv.c new file mode 100644 index 0000000..bae16204 --- /dev/null +++ b/drivers/uwb/rsv.c @@ -0,0 +1,680 @@ +/* + * 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/version.h> +#include <linux/kernel.h> +#include <linux/uwb.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] = "initiated", + [UWB_RSV_STATE_O_PENDING] = "pending", + [UWB_RSV_STATE_O_MODIFIED] = "modified", + [UWB_RSV_STATE_O_ESTABLISHED] = "established", + [UWB_RSV_STATE_T_ACCEPTED] = "accepted", + [UWB_RSV_STATE_T_DENIED] = "denied", + [UWB_RSV_STATE_T_PENDING] = "pending", +}; + +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", +}; + +/** + * 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); + +static void uwb_rsv_dump(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\n", owner, target, uwb_rsv_state_str(rsv->state)); +} + +/* + * 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; + 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) + return -EBUSY; + + rsv->stream = stream; + set_bit(stream, streams_bm); + + return 0; +} + +static void uwb_rsv_put_stream(struct uwb_rsv *rsv) +{ + struct uwb_rc *rc = rsv->rc; + 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); +} + +/* + * Generate a MAS allocation with a single row component. + */ +static void uwb_rsv_gen_alloc_row(struct uwb_mas_bm *mas, + int first_mas, int mas_per_zone, + int zs, int ze) +{ + struct uwb_mas_bm col; + int z; + + bitmap_zero(mas->bm, UWB_NUM_MAS); + bitmap_zero(col.bm, UWB_NUM_MAS); + bitmap_fill(col.bm, mas_per_zone); + bitmap_shift_left(col.bm, col.bm, first_mas + zs * UWB_MAS_PER_ZONE, UWB_NUM_MAS); + + for (z = zs; z <= ze; z++) { + bitmap_or(mas->bm, mas->bm, col.bm, UWB_NUM_MAS); + bitmap_shift_left(col.bm, col.bm, UWB_MAS_PER_ZONE, UWB_NUM_MAS); + } +} + +/* + * Allocate some MAS for this reservation based on current local + * availability, the reservation parameters (max_mas, min_mas, + * sparsity), and the WiMedia rules for MAS allocations. + * + * Returns -EBUSY is insufficient free MAS are available. + * + * FIXME: to simplify this, only safe reservations with a single row + * component in zones 1 to 15 are tried (zone 0 is skipped to avoid + * problems with the MAS reserved for the BP). + * + * [ECMA-368] section B.2. + */ +static int uwb_rsv_alloc_mas(struct uwb_rsv *rsv) +{ + static const int safe_mas_in_row[UWB_NUM_ZONES] = { + 8, 7, 6, 5, 4, 4, 4, 4, 4, 4, 4, 4, 4, 3, 2, 1, + }; + int n, r; + struct uwb_mas_bm mas; + bool found = false; + + /* + * Search all valid safe allocations until either: too few MAS + * are available; or the smallest allocation with sufficient + * MAS is found. + * + * The top of the zones are preferred, so space for larger + * allocations is available in the bottom of the zone (e.g., a + * 15 MAS allocation should start in row 14 leaving space for + * a 120 MAS allocation at row 0). + */ + for (n = safe_mas_in_row[0]; n >= 1; n--) { + int num_mas; + + num_mas = n * (UWB_NUM_ZONES - 1); + if (num_mas < rsv->min_mas) + break; + if (found && num_mas < rsv->max_mas) + break; + + for (r = UWB_MAS_PER_ZONE-1; r >= 0; r--) { + if (safe_mas_in_row[r] < n) + continue; + uwb_rsv_gen_alloc_row(&mas, r, n, 1, UWB_NUM_ZONES); + if (uwb_drp_avail_reserve_pending(rsv->rc, &mas) == 0) { + found = true; + break; + } + } + } + + if (!found) + return -EBUSY; + + bitmap_copy(rsv->mas.bm, mas.bm, UWB_NUM_MAS); + return 0; +} + +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->is_multicast) { + if (rsv->state == UWB_RSV_STATE_O_INITIATED) + sframes = 1; + if (rsv->state == UWB_RSV_STATE_O_ESTABLISHED) + sframes = 0; + } + + rsv->expired = false; + 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(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) +{ + if (rsv->state == new_state) { + switch (rsv->state) { + case UWB_RSV_STATE_O_ESTABLISHED: + case UWB_RSV_STATE_T_ACCEPTED: + case UWB_RSV_STATE_NONE: + uwb_rsv_stroke_timer(rsv); + break; + default: + /* Expecting a state transition so leave timer + as-is. */ + break; + } + return; + } + + switch (new_state) { + case UWB_RSV_STATE_NONE: + uwb_drp_avail_release(rsv->rc, &rsv->mas); + uwb_rsv_put_stream(rsv); + uwb_rsv_state_update(rsv, UWB_RSV_STATE_NONE); + 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_ESTABLISHED: + 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_T_ACCEPTED: + 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; + default: + dev_err(&rsv->rc->uwb_dev.dev, "unhandled state: %s (%d)\n", + uwb_rsv_state_str(new_state), new_state); + } +} + +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); + init_timer(&rsv->timer); + rsv->timer.function = uwb_rsv_timer; + rsv->timer.data = (unsigned long)rsv; + + rsv->rc = rc; + + return rsv; +} + +static void uwb_rsv_free(struct uwb_rsv *rsv) +{ + uwb_dev_put(rsv->owner); + if (rsv->target.type == UWB_RSV_TARGET_DEV) + uwb_dev_put(rsv->target.dev); + kfree(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) +{ + if (rsv->state != UWB_RSV_STATE_NONE) + uwb_rsv_set_state(rsv, UWB_RSV_STATE_NONE); + del_timer_sync(&rsv->timer); + list_del(&rsv->rc_node); + uwb_rsv_free(rsv); +} + +/** + * uwb_rsv_destroy - free a UWB reservation structure + * @rsv: the reservation to free + * + * The reservation will be terminated if it is pending or established. + */ +void uwb_rsv_destroy(struct uwb_rsv *rsv) +{ + struct uwb_rc *rc = rsv->rc; + + mutex_lock(&rc->rsvs_mutex); + uwb_rsv_remove(rsv); + mutex_unlock(&rc->rsvs_mutex); +} +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, sparsity 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; + int ret; + + mutex_lock(&rc->rsvs_mutex); + + ret = uwb_rsv_get_stream(rsv); + if (ret) + goto out; + + ret = uwb_rsv_alloc_mas(rsv); + if (ret) { + uwb_rsv_put_stream(rsv); + goto out; + } + + 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 + * @sparsity: new sparsity 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 sparsity) +{ + return -ENOSYS; +} +EXPORT_SYMBOL_GPL(uwb_rsv_modify); + +/** + * 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); + + 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. + */ +void uwb_rsv_accept(struct uwb_rsv *rsv, uwb_rsv_cb_f cb, void *pal_priv) +{ + 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; + rsv->type = uwb_ie_drp_type(drp_ie); + rsv->stream = uwb_ie_drp_stream_index(drp_ie); + set_bit(rsv->stream, rsv->owner->streams); + 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; + spin_lock(&rc->pal_lock); + list_for_each_entry(pal, &rc->pals, node) { + if (pal->new_rsv) + pal->new_rsv(rsv); + if (rsv->state == UWB_RSV_STATE_T_ACCEPTED) + break; + } + spin_unlock(&rc->pal_lock); + + list_add_tail(&rsv->rc_node, &rc->reservations); + state = rsv->state; + rsv->state = UWB_RSV_STATE_NONE; + uwb_rsv_set_state(rsv, state); + + return rsv; +} + +/** + * 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->expired) + uwb_drp_handle_timeout(rsv); + if (!rsv->ie_valid) { + uwb_drp_ie_update(rsv); + ie_updated = true; + } + } + + return ie_updated; +} + +void uwb_rsv_sched_update(struct uwb_rc *rc) +{ + queue_work(rc->rsv_workq, &rc->rsv_update_work); +} + +/* + * 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); + 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) + uwb_rc_send_all_drp_ie(rc); + + mutex_unlock(&rc->rsvs_mutex); +} + +static void uwb_rsv_timer(unsigned long arg) +{ + struct uwb_rsv *rsv = (struct uwb_rsv *)arg; + + rsv->expired = true; + uwb_rsv_sched_update(rsv->rc); +} + +void uwb_rsv_init(struct uwb_rc *rc) +{ + INIT_LIST_HEAD(&rc->reservations); + mutex_init(&rc->rsvs_mutex); + INIT_WORK(&rc->rsv_update_work, uwb_rsv_update_work); + + 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) +{ + struct uwb_rsv *rsv, *t; + + 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); + + cancel_work_sync(&rc->rsv_update_work); + destroy_workqueue(rc->rsv_workq); +} |