1/* 2 * UWB DRP IE management. 3 * 4 * Copyright (C) 2005-2006 Intel Corporation 5 * Copyright (C) 2008 Cambridge Silicon Radio Ltd. 6 * 7 * This program is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License version 9 * 2 as published by the Free Software Foundation. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program. If not, see <http://www.gnu.org/licenses/>. 18 */ 19#include <linux/kernel.h> 20#include <linux/random.h> 21#include <linux/slab.h> 22#include <linux/uwb.h> 23 24#include "uwb-internal.h" 25 26 27/* 28 * Return the reason code for a reservations's DRP IE. 29 */ 30int uwb_rsv_reason_code(struct uwb_rsv *rsv) 31{ 32 static const int reason_codes[] = { 33 [UWB_RSV_STATE_O_INITIATED] = UWB_DRP_REASON_ACCEPTED, 34 [UWB_RSV_STATE_O_PENDING] = UWB_DRP_REASON_ACCEPTED, 35 [UWB_RSV_STATE_O_MODIFIED] = UWB_DRP_REASON_MODIFIED, 36 [UWB_RSV_STATE_O_ESTABLISHED] = UWB_DRP_REASON_ACCEPTED, 37 [UWB_RSV_STATE_O_TO_BE_MOVED] = UWB_DRP_REASON_ACCEPTED, 38 [UWB_RSV_STATE_O_MOVE_COMBINING] = UWB_DRP_REASON_MODIFIED, 39 [UWB_RSV_STATE_O_MOVE_REDUCING] = UWB_DRP_REASON_MODIFIED, 40 [UWB_RSV_STATE_O_MOVE_EXPANDING] = UWB_DRP_REASON_ACCEPTED, 41 [UWB_RSV_STATE_T_ACCEPTED] = UWB_DRP_REASON_ACCEPTED, 42 [UWB_RSV_STATE_T_CONFLICT] = UWB_DRP_REASON_CONFLICT, 43 [UWB_RSV_STATE_T_PENDING] = UWB_DRP_REASON_PENDING, 44 [UWB_RSV_STATE_T_DENIED] = UWB_DRP_REASON_DENIED, 45 [UWB_RSV_STATE_T_RESIZED] = UWB_DRP_REASON_ACCEPTED, 46 [UWB_RSV_STATE_T_EXPANDING_ACCEPTED] = UWB_DRP_REASON_ACCEPTED, 47 [UWB_RSV_STATE_T_EXPANDING_CONFLICT] = UWB_DRP_REASON_CONFLICT, 48 [UWB_RSV_STATE_T_EXPANDING_PENDING] = UWB_DRP_REASON_PENDING, 49 [UWB_RSV_STATE_T_EXPANDING_DENIED] = UWB_DRP_REASON_DENIED, 50 }; 51 52 return reason_codes[rsv->state]; 53} 54 55/* 56 * Return the reason code for a reservations's companion DRP IE . 57 */ 58int uwb_rsv_companion_reason_code(struct uwb_rsv *rsv) 59{ 60 static const int companion_reason_codes[] = { 61 [UWB_RSV_STATE_O_MOVE_EXPANDING] = UWB_DRP_REASON_ACCEPTED, 62 [UWB_RSV_STATE_T_EXPANDING_ACCEPTED] = UWB_DRP_REASON_ACCEPTED, 63 [UWB_RSV_STATE_T_EXPANDING_CONFLICT] = UWB_DRP_REASON_CONFLICT, 64 [UWB_RSV_STATE_T_EXPANDING_PENDING] = UWB_DRP_REASON_PENDING, 65 [UWB_RSV_STATE_T_EXPANDING_DENIED] = UWB_DRP_REASON_DENIED, 66 }; 67 68 return companion_reason_codes[rsv->state]; 69} 70 71/* 72 * Return the status bit for a reservations's DRP IE. 73 */ 74int uwb_rsv_status(struct uwb_rsv *rsv) 75{ 76 static const int statuses[] = { 77 [UWB_RSV_STATE_O_INITIATED] = 0, 78 [UWB_RSV_STATE_O_PENDING] = 0, 79 [UWB_RSV_STATE_O_MODIFIED] = 1, 80 [UWB_RSV_STATE_O_ESTABLISHED] = 1, 81 [UWB_RSV_STATE_O_TO_BE_MOVED] = 0, 82 [UWB_RSV_STATE_O_MOVE_COMBINING] = 1, 83 [UWB_RSV_STATE_O_MOVE_REDUCING] = 1, 84 [UWB_RSV_STATE_O_MOVE_EXPANDING] = 1, 85 [UWB_RSV_STATE_T_ACCEPTED] = 1, 86 [UWB_RSV_STATE_T_CONFLICT] = 0, 87 [UWB_RSV_STATE_T_PENDING] = 0, 88 [UWB_RSV_STATE_T_DENIED] = 0, 89 [UWB_RSV_STATE_T_RESIZED] = 1, 90 [UWB_RSV_STATE_T_EXPANDING_ACCEPTED] = 1, 91 [UWB_RSV_STATE_T_EXPANDING_CONFLICT] = 1, 92 [UWB_RSV_STATE_T_EXPANDING_PENDING] = 1, 93 [UWB_RSV_STATE_T_EXPANDING_DENIED] = 1, 94 95 }; 96 97 return statuses[rsv->state]; 98} 99 100/* 101 * Return the status bit for a reservations's companion DRP IE . 102 */ 103int uwb_rsv_companion_status(struct uwb_rsv *rsv) 104{ 105 static const int companion_statuses[] = { 106 [UWB_RSV_STATE_O_MOVE_EXPANDING] = 0, 107 [UWB_RSV_STATE_T_EXPANDING_ACCEPTED] = 1, 108 [UWB_RSV_STATE_T_EXPANDING_CONFLICT] = 0, 109 [UWB_RSV_STATE_T_EXPANDING_PENDING] = 0, 110 [UWB_RSV_STATE_T_EXPANDING_DENIED] = 0, 111 }; 112 113 return companion_statuses[rsv->state]; 114} 115 116/* 117 * Allocate a DRP IE. 118 * 119 * To save having to free/allocate a DRP IE when its MAS changes, 120 * enough memory is allocated for the maxiumum number of DRP 121 * allocation fields. This gives an overhead per reservation of up to 122 * (UWB_NUM_ZONES - 1) * 4 = 60 octets. 123 */ 124static struct uwb_ie_drp *uwb_drp_ie_alloc(void) 125{ 126 struct uwb_ie_drp *drp_ie; 127 128 drp_ie = kzalloc(sizeof(struct uwb_ie_drp) + 129 UWB_NUM_ZONES * sizeof(struct uwb_drp_alloc), 130 GFP_KERNEL); 131 if (drp_ie) { 132 drp_ie->hdr.element_id = UWB_IE_DRP; 133 } 134 return drp_ie; 135} 136 137 138/* 139 * Fill a DRP IE's allocation fields from a MAS bitmap. 140 */ 141static void uwb_drp_ie_from_bm(struct uwb_ie_drp *drp_ie, 142 struct uwb_mas_bm *mas) 143{ 144 int z, i, num_fields = 0, next = 0; 145 struct uwb_drp_alloc *zones; 146 __le16 current_bmp; 147 DECLARE_BITMAP(tmp_bmp, UWB_NUM_MAS); 148 DECLARE_BITMAP(tmp_mas_bm, UWB_MAS_PER_ZONE); 149 150 zones = drp_ie->allocs; 151 152 bitmap_copy(tmp_bmp, mas->bm, UWB_NUM_MAS); 153 154 /* Determine unique MAS bitmaps in zones from bitmap. */ 155 for (z = 0; z < UWB_NUM_ZONES; z++) { 156 bitmap_copy(tmp_mas_bm, tmp_bmp, UWB_MAS_PER_ZONE); 157 if (bitmap_weight(tmp_mas_bm, UWB_MAS_PER_ZONE) > 0) { 158 bool found = false; 159 current_bmp = (__le16) *tmp_mas_bm; 160 for (i = 0; i < next; i++) { 161 if (current_bmp == zones[i].mas_bm) { 162 zones[i].zone_bm |= 1 << z; 163 found = true; 164 break; 165 } 166 } 167 if (!found) { 168 num_fields++; 169 zones[next].zone_bm = 1 << z; 170 zones[next].mas_bm = current_bmp; 171 next++; 172 } 173 } 174 bitmap_shift_right(tmp_bmp, tmp_bmp, UWB_MAS_PER_ZONE, UWB_NUM_MAS); 175 } 176 177 /* Store in format ready for transmission (le16). */ 178 for (i = 0; i < num_fields; i++) { 179 drp_ie->allocs[i].zone_bm = cpu_to_le16(zones[i].zone_bm); 180 drp_ie->allocs[i].mas_bm = cpu_to_le16(zones[i].mas_bm); 181 } 182 183 drp_ie->hdr.length = sizeof(struct uwb_ie_drp) - sizeof(struct uwb_ie_hdr) 184 + num_fields * sizeof(struct uwb_drp_alloc); 185} 186 187/** 188 * uwb_drp_ie_update - update a reservation's DRP IE 189 * @rsv: the reservation 190 */ 191int uwb_drp_ie_update(struct uwb_rsv *rsv) 192{ 193 struct uwb_ie_drp *drp_ie; 194 struct uwb_rsv_move *mv; 195 int unsafe; 196 197 if (rsv->state == UWB_RSV_STATE_NONE) { 198 kfree(rsv->drp_ie); 199 rsv->drp_ie = NULL; 200 return 0; 201 } 202 203 unsafe = rsv->mas.unsafe ? 1 : 0; 204 205 if (rsv->drp_ie == NULL) { 206 rsv->drp_ie = uwb_drp_ie_alloc(); 207 if (rsv->drp_ie == NULL) 208 return -ENOMEM; 209 } 210 drp_ie = rsv->drp_ie; 211 212 uwb_ie_drp_set_unsafe(drp_ie, unsafe); 213 uwb_ie_drp_set_tiebreaker(drp_ie, rsv->tiebreaker); 214 uwb_ie_drp_set_owner(drp_ie, uwb_rsv_is_owner(rsv)); 215 uwb_ie_drp_set_status(drp_ie, uwb_rsv_status(rsv)); 216 uwb_ie_drp_set_reason_code(drp_ie, uwb_rsv_reason_code(rsv)); 217 uwb_ie_drp_set_stream_index(drp_ie, rsv->stream); 218 uwb_ie_drp_set_type(drp_ie, rsv->type); 219 220 if (uwb_rsv_is_owner(rsv)) { 221 switch (rsv->target.type) { 222 case UWB_RSV_TARGET_DEV: 223 drp_ie->dev_addr = rsv->target.dev->dev_addr; 224 break; 225 case UWB_RSV_TARGET_DEVADDR: 226 drp_ie->dev_addr = rsv->target.devaddr; 227 break; 228 } 229 } else 230 drp_ie->dev_addr = rsv->owner->dev_addr; 231 232 uwb_drp_ie_from_bm(drp_ie, &rsv->mas); 233 234 if (uwb_rsv_has_two_drp_ies(rsv)) { 235 mv = &rsv->mv; 236 if (mv->companion_drp_ie == NULL) { 237 mv->companion_drp_ie = uwb_drp_ie_alloc(); 238 if (mv->companion_drp_ie == NULL) 239 return -ENOMEM; 240 } 241 drp_ie = mv->companion_drp_ie; 242 243 /* keep all the same configuration of the main drp_ie */ 244 memcpy(drp_ie, rsv->drp_ie, sizeof(struct uwb_ie_drp)); 245 246 247 uwb_ie_drp_set_unsafe(drp_ie, 1); 248 uwb_ie_drp_set_status(drp_ie, uwb_rsv_companion_status(rsv)); 249 uwb_ie_drp_set_reason_code(drp_ie, uwb_rsv_companion_reason_code(rsv)); 250 251 uwb_drp_ie_from_bm(drp_ie, &mv->companion_mas); 252 } 253 254 rsv->ie_valid = true; 255 return 0; 256} 257 258/* 259 * Set MAS bits from given MAS bitmap in a single zone of large bitmap. 260 * 261 * We are given a zone id and the MAS bitmap of bits that need to be set in 262 * this zone. Note that this zone may already have bits set and this only 263 * adds settings - we cannot simply assign the MAS bitmap contents to the 264 * zone contents. We iterate over the the bits (MAS) in the zone and set the 265 * bits that are set in the given MAS bitmap. 266 */ 267static 268void uwb_drp_ie_single_zone_to_bm(struct uwb_mas_bm *bm, u8 zone, u16 mas_bm) 269{ 270 int mas; 271 u16 mas_mask; 272 273 for (mas = 0; mas < UWB_MAS_PER_ZONE; mas++) { 274 mas_mask = 1 << mas; 275 if (mas_bm & mas_mask) 276 set_bit(zone * UWB_NUM_ZONES + mas, bm->bm); 277 } 278} 279 280/** 281 * uwb_drp_ie_zones_to_bm - convert DRP allocation fields to a bitmap 282 * @mas: MAS bitmap that will be populated to correspond to the 283 * allocation fields in the DRP IE 284 * @drp_ie: the DRP IE that contains the allocation fields. 285 * 286 * The input format is an array of MAS allocation fields (16 bit Zone 287 * bitmap, 16 bit MAS bitmap) as described in [ECMA-368] section 288 * 16.8.6. The output is a full 256 bit MAS bitmap. 289 * 290 * We go over all the allocation fields, for each allocation field we 291 * know which zones are impacted. We iterate over all the zones 292 * impacted and call a function that will set the correct MAS bits in 293 * each zone. 294 */ 295void uwb_drp_ie_to_bm(struct uwb_mas_bm *bm, const struct uwb_ie_drp *drp_ie) 296{ 297 int numallocs = (drp_ie->hdr.length - 4) / 4; 298 const struct uwb_drp_alloc *alloc; 299 int cnt; 300 u16 zone_bm, mas_bm; 301 u8 zone; 302 u16 zone_mask; 303 304 bitmap_zero(bm->bm, UWB_NUM_MAS); 305 306 for (cnt = 0; cnt < numallocs; cnt++) { 307 alloc = &drp_ie->allocs[cnt]; 308 zone_bm = le16_to_cpu(alloc->zone_bm); 309 mas_bm = le16_to_cpu(alloc->mas_bm); 310 for (zone = 0; zone < UWB_NUM_ZONES; zone++) { 311 zone_mask = 1 << zone; 312 if (zone_bm & zone_mask) 313 uwb_drp_ie_single_zone_to_bm(bm, zone, mas_bm); 314 } 315 } 316} 317