LXR linux/drivers/uwb/drp-ie.c

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * UWB DRP IE management.
   4 *
   5 * Copyright (C) 2005-2006 Intel Corporation
   6 * Copyright (C) 2008 Cambridge Silicon Radio Ltd.
   7 */
   8#include <linux/kernel.h>
   9#include <linux/random.h>
  10#include <linux/slab.h>
  11#include <linux/uwb.h>
  12
  13#include "uwb-internal.h"
  14
  15
  16/*
  17 * Return the reason code for a reservations's DRP IE.
  18 */
  19static int uwb_rsv_reason_code(struct uwb_rsv *rsv)
  20{
  21        static const int reason_codes[] = {
  22                [UWB_RSV_STATE_O_INITIATED]          = UWB_DRP_REASON_ACCEPTED,
  23                [UWB_RSV_STATE_O_PENDING]            = UWB_DRP_REASON_ACCEPTED,
  24                [UWB_RSV_STATE_O_MODIFIED]           = UWB_DRP_REASON_MODIFIED,
  25                [UWB_RSV_STATE_O_ESTABLISHED]        = UWB_DRP_REASON_ACCEPTED,
  26                [UWB_RSV_STATE_O_TO_BE_MOVED]        = UWB_DRP_REASON_ACCEPTED,
  27                [UWB_RSV_STATE_O_MOVE_COMBINING]     = UWB_DRP_REASON_MODIFIED,
  28                [UWB_RSV_STATE_O_MOVE_REDUCING]      = UWB_DRP_REASON_MODIFIED,
  29                [UWB_RSV_STATE_O_MOVE_EXPANDING]     = UWB_DRP_REASON_ACCEPTED,
  30                [UWB_RSV_STATE_T_ACCEPTED]           = UWB_DRP_REASON_ACCEPTED,
  31                [UWB_RSV_STATE_T_CONFLICT]           = UWB_DRP_REASON_CONFLICT,
  32                [UWB_RSV_STATE_T_PENDING]            = UWB_DRP_REASON_PENDING,
  33                [UWB_RSV_STATE_T_DENIED]             = UWB_DRP_REASON_DENIED,
  34                [UWB_RSV_STATE_T_RESIZED]            = UWB_DRP_REASON_ACCEPTED,
  35                [UWB_RSV_STATE_T_EXPANDING_ACCEPTED] = UWB_DRP_REASON_ACCEPTED,
  36                [UWB_RSV_STATE_T_EXPANDING_CONFLICT] = UWB_DRP_REASON_CONFLICT,
  37                [UWB_RSV_STATE_T_EXPANDING_PENDING]  = UWB_DRP_REASON_PENDING,
  38                [UWB_RSV_STATE_T_EXPANDING_DENIED]   = UWB_DRP_REASON_DENIED,
  39        };
  40
  41        return reason_codes[rsv->state];
  42}
  43
  44/*
  45 * Return the reason code for a reservations's companion DRP IE .
  46 */
  47static int uwb_rsv_companion_reason_code(struct uwb_rsv *rsv)
  48{
  49        static const int companion_reason_codes[] = {
  50                [UWB_RSV_STATE_O_MOVE_EXPANDING]     = UWB_DRP_REASON_ACCEPTED,
  51                [UWB_RSV_STATE_T_EXPANDING_ACCEPTED] = UWB_DRP_REASON_ACCEPTED,
  52                [UWB_RSV_STATE_T_EXPANDING_CONFLICT] = UWB_DRP_REASON_CONFLICT,
  53                [UWB_RSV_STATE_T_EXPANDING_PENDING]  = UWB_DRP_REASON_PENDING,
  54                [UWB_RSV_STATE_T_EXPANDING_DENIED]   = UWB_DRP_REASON_DENIED,
  55        };
  56
  57        return companion_reason_codes[rsv->state];
  58}
  59
  60/*
  61 * Return the status bit for a reservations's DRP IE.
  62 */
  63int uwb_rsv_status(struct uwb_rsv *rsv)
  64{
  65        static const int statuses[] = {
  66                [UWB_RSV_STATE_O_INITIATED]          = 0,
  67                [UWB_RSV_STATE_O_PENDING]            = 0,
  68                [UWB_RSV_STATE_O_MODIFIED]           = 1,
  69                [UWB_RSV_STATE_O_ESTABLISHED]        = 1,
  70                [UWB_RSV_STATE_O_TO_BE_MOVED]        = 0,
  71                [UWB_RSV_STATE_O_MOVE_COMBINING]     = 1,
  72                [UWB_RSV_STATE_O_MOVE_REDUCING]      = 1,
  73                [UWB_RSV_STATE_O_MOVE_EXPANDING]     = 1,
  74                [UWB_RSV_STATE_T_ACCEPTED]           = 1,
  75                [UWB_RSV_STATE_T_CONFLICT]           = 0,
  76                [UWB_RSV_STATE_T_PENDING]            = 0,
  77                [UWB_RSV_STATE_T_DENIED]             = 0,
  78                [UWB_RSV_STATE_T_RESIZED]            = 1,
  79                [UWB_RSV_STATE_T_EXPANDING_ACCEPTED] = 1,
  80                [UWB_RSV_STATE_T_EXPANDING_CONFLICT] = 1,
  81                [UWB_RSV_STATE_T_EXPANDING_PENDING]  = 1,
  82                [UWB_RSV_STATE_T_EXPANDING_DENIED]   = 1,
  83
  84        };
  85
  86        return statuses[rsv->state];
  87}
  88
  89/*
  90 * Return the status bit for a reservations's companion DRP IE .
  91 */
  92int uwb_rsv_companion_status(struct uwb_rsv *rsv)
  93{
  94        static const int companion_statuses[] = {
  95                [UWB_RSV_STATE_O_MOVE_EXPANDING]     = 0,
  96                [UWB_RSV_STATE_T_EXPANDING_ACCEPTED] = 1,
  97                [UWB_RSV_STATE_T_EXPANDING_CONFLICT] = 0,
  98                [UWB_RSV_STATE_T_EXPANDING_PENDING]  = 0,
  99                [UWB_RSV_STATE_T_EXPANDING_DENIED]   = 0,
 100        };
 101
 102        return companion_statuses[rsv->state];
 103}
 104
 105/*
 106 * Allocate a DRP IE.
 107 *
 108 * To save having to free/allocate a DRP IE when its MAS changes,
 109 * enough memory is allocated for the maxiumum number of DRP
 110 * allocation fields.  This gives an overhead per reservation of up to
 111 * (UWB_NUM_ZONES - 1) * 4 = 60 octets.
 112 */
 113static struct uwb_ie_drp *uwb_drp_ie_alloc(void)
 114{
 115        struct uwb_ie_drp *drp_ie;
 116
 117        drp_ie = kzalloc(struct_size(drp_ie, allocs, UWB_NUM_ZONES),
 118                         GFP_KERNEL);
 119        if (drp_ie)
 120                drp_ie->hdr.element_id = UWB_IE_DRP;
 121        return drp_ie;
 122}
 123
 124
 125/*
 126 * Fill a DRP IE's allocation fields from a MAS bitmap.
 127 */
 128static void uwb_drp_ie_from_bm(struct uwb_ie_drp *drp_ie,
 129                               struct uwb_mas_bm *mas)
 130{
 131        int z, i, num_fields = 0, next = 0;
 132        struct uwb_drp_alloc *zones;
 133        __le16 current_bmp;
 134        DECLARE_BITMAP(tmp_bmp, UWB_NUM_MAS);
 135        DECLARE_BITMAP(tmp_mas_bm, UWB_MAS_PER_ZONE);
 136
 137        zones = drp_ie->allocs;
 138
 139        bitmap_copy(tmp_bmp, mas->bm, UWB_NUM_MAS);
 140
 141        /* Determine unique MAS bitmaps in zones from bitmap. */
 142        for (z = 0; z < UWB_NUM_ZONES; z++) {
 143                bitmap_copy(tmp_mas_bm, tmp_bmp, UWB_MAS_PER_ZONE);
 144                if (bitmap_weight(tmp_mas_bm, UWB_MAS_PER_ZONE) > 0) {
 145                        bool found = false;
 146                        current_bmp = (__le16) *tmp_mas_bm;
 147                        for (i = 0; i < next; i++) {
 148                                if (current_bmp == zones[i].mas_bm) {
 149                                        zones[i].zone_bm |= 1 << z;
 150                                        found = true;
 151                                        break;
 152                                }
 153                        }
 154                        if (!found)  {
 155                                num_fields++;
 156                                zones[next].zone_bm = 1 << z;
 157                                zones[next].mas_bm = current_bmp;
 158                                next++;
 159                        }
 160                }
 161                bitmap_shift_right(tmp_bmp, tmp_bmp, UWB_MAS_PER_ZONE, UWB_NUM_MAS);
 162        }
 163
 164        /* Store in format ready for transmission (le16). */
 165        for (i = 0; i < num_fields; i++) {
 166                drp_ie->allocs[i].zone_bm = cpu_to_le16(zones[i].zone_bm);
 167                drp_ie->allocs[i].mas_bm = cpu_to_le16(zones[i].mas_bm);
 168        }
 169
 170        drp_ie->hdr.length = sizeof(struct uwb_ie_drp) - sizeof(struct uwb_ie_hdr)
 171                + num_fields * sizeof(struct uwb_drp_alloc);
 172}
 173
 174/**
 175 * uwb_drp_ie_update - update a reservation's DRP IE
 176 * @rsv: the reservation
 177 */
 178int uwb_drp_ie_update(struct uwb_rsv *rsv)
 179{
 180        struct uwb_ie_drp *drp_ie;
 181        struct uwb_rsv_move *mv;
 182        int unsafe;
 183
 184        if (rsv->state == UWB_RSV_STATE_NONE) {
 185                kfree(rsv->drp_ie);
 186                rsv->drp_ie = NULL;
 187                return 0;
 188        }
 189
 190        unsafe = rsv->mas.unsafe ? 1 : 0;
 191
 192        if (rsv->drp_ie == NULL) {
 193                rsv->drp_ie = uwb_drp_ie_alloc();
 194                if (rsv->drp_ie == NULL)
 195                        return -ENOMEM;
 196        }
 197        drp_ie = rsv->drp_ie;
 198
 199        uwb_ie_drp_set_unsafe(drp_ie,       unsafe);
 200        uwb_ie_drp_set_tiebreaker(drp_ie,   rsv->tiebreaker);
 201        uwb_ie_drp_set_owner(drp_ie,        uwb_rsv_is_owner(rsv));
 202        uwb_ie_drp_set_status(drp_ie,       uwb_rsv_status(rsv));
 203        uwb_ie_drp_set_reason_code(drp_ie,  uwb_rsv_reason_code(rsv));
 204        uwb_ie_drp_set_stream_index(drp_ie, rsv->stream);
 205        uwb_ie_drp_set_type(drp_ie,         rsv->type);
 206
 207        if (uwb_rsv_is_owner(rsv)) {
 208                switch (rsv->target.type) {
 209                case UWB_RSV_TARGET_DEV:
 210                        drp_ie->dev_addr = rsv->target.dev->dev_addr;
 211                        break;
 212                case UWB_RSV_TARGET_DEVADDR:
 213                        drp_ie->dev_addr = rsv->target.devaddr;
 214                        break;
 215                }
 216        } else
 217                drp_ie->dev_addr = rsv->owner->dev_addr;
 218
 219        uwb_drp_ie_from_bm(drp_ie, &rsv->mas);
 220
 221        if (uwb_rsv_has_two_drp_ies(rsv)) {
 222                mv = &rsv->mv;
 223                if (mv->companion_drp_ie == NULL) {
 224                        mv->companion_drp_ie = uwb_drp_ie_alloc();
 225                        if (mv->companion_drp_ie == NULL)
 226                                return -ENOMEM;
 227                }
 228                drp_ie = mv->companion_drp_ie;
 229
 230                /* keep all the same configuration of the main drp_ie */
 231                memcpy(drp_ie, rsv->drp_ie, sizeof(struct uwb_ie_drp));
 232
 233
 234                /* FIXME: handle properly the unsafe bit */
 235                uwb_ie_drp_set_unsafe(drp_ie,       1);
 236                uwb_ie_drp_set_status(drp_ie,       uwb_rsv_companion_status(rsv));
 237                uwb_ie_drp_set_reason_code(drp_ie,  uwb_rsv_companion_reason_code(rsv));
 238
 239                uwb_drp_ie_from_bm(drp_ie, &mv->companion_mas);
 240        }
 241
 242        rsv->ie_valid = true;
 243        return 0;
 244}
 245
 246/*
 247 * Set MAS bits from given MAS bitmap in a single zone of large bitmap.
 248 *
 249 * We are given a zone id and the MAS bitmap of bits that need to be set in
 250 * this zone. Note that this zone may already have bits set and this only
 251 * adds settings - we cannot simply assign the MAS bitmap contents to the
 252 * zone contents. We iterate over the the bits (MAS) in the zone and set the
 253 * bits that are set in the given MAS bitmap.
 254 */
 255static
 256void uwb_drp_ie_single_zone_to_bm(struct uwb_mas_bm *bm, u8 zone, u16 mas_bm)
 257{
 258        int mas;
 259        u16 mas_mask;
 260
 261        for (mas = 0; mas < UWB_MAS_PER_ZONE; mas++) {
 262                mas_mask = 1 << mas;
 263                if (mas_bm & mas_mask)
 264                        set_bit(zone * UWB_NUM_ZONES + mas, bm->bm);
 265        }
 266}
 267
 268/**
 269 * uwb_drp_ie_zones_to_bm - convert DRP allocation fields to a bitmap
 270 * @mas:    MAS bitmap that will be populated to correspond to the
 271 *          allocation fields in the DRP IE
 272 * @drp_ie: the DRP IE that contains the allocation fields.
 273 *
 274 * The input format is an array of MAS allocation fields (16 bit Zone
 275 * bitmap, 16 bit MAS bitmap) as described in [ECMA-368] section
 276 * 16.8.6. The output is a full 256 bit MAS bitmap.
 277 *
 278 * We go over all the allocation fields, for each allocation field we
 279 * know which zones are impacted. We iterate over all the zones
 280 * impacted and call a function that will set the correct MAS bits in
 281 * each zone.
 282 */
 283void uwb_drp_ie_to_bm(struct uwb_mas_bm *bm, const struct uwb_ie_drp *drp_ie)
 284{
 285        int numallocs = (drp_ie->hdr.length - 4) / 4;
 286        const struct uwb_drp_alloc *alloc;
 287        int cnt;
 288        u16 zone_bm, mas_bm;
 289        u8 zone;
 290        u16 zone_mask;
 291
 292        bitmap_zero(bm->bm, UWB_NUM_MAS);
 293
 294        for (cnt = 0; cnt < numallocs; cnt++) {
 295                alloc = &drp_ie->allocs[cnt];
 296                zone_bm = le16_to_cpu(alloc->zone_bm);
 297                mas_bm = le16_to_cpu(alloc->mas_bm);
 298                for (zone = 0; zone < UWB_NUM_ZONES; zone++)   {
 299                        zone_mask = 1 << zone;
 300                        if (zone_bm & zone_mask)
 301                                uwb_drp_ie_single_zone_to_bm(bm, zone, mas_bm);
 302                }
 303        }
 304}
 305
 306