aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/uwb/drp-ie.c
blob: 2840d7bf9e67eff12c9b743c04eb01c0120763cd (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
/*
 * 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/kernel.h>
#include <linux/random.h>
#include <linux/uwb.h>

#include "uwb-internal.h"


/*
 * Return the reason code for a reservations's DRP IE.
 */
int uwb_rsv_reason_code(struct uwb_rsv *rsv)
{
	static const int reason_codes[] = {
		[UWB_RSV_STATE_O_INITIATED]          = UWB_DRP_REASON_ACCEPTED,
		[UWB_RSV_STATE_O_PENDING]            = UWB_DRP_REASON_ACCEPTED,
		[UWB_RSV_STATE_O_MODIFIED]           = UWB_DRP_REASON_MODIFIED,
		[UWB_RSV_STATE_O_ESTABLISHED]        = UWB_DRP_REASON_ACCEPTED,
		[UWB_RSV_STATE_O_TO_BE_MOVED]        = UWB_DRP_REASON_ACCEPTED,
		[UWB_RSV_STATE_O_MOVE_COMBINING]     = UWB_DRP_REASON_MODIFIED,
		[UWB_RSV_STATE_O_MOVE_REDUCING]      = UWB_DRP_REASON_MODIFIED,
		[UWB_RSV_STATE_O_MOVE_EXPANDING]     = UWB_DRP_REASON_ACCEPTED,
		[UWB_RSV_STATE_T_ACCEPTED]           = UWB_DRP_REASON_ACCEPTED,
		[UWB_RSV_STATE_T_CONFLICT]           = UWB_DRP_REASON_CONFLICT,
		[UWB_RSV_STATE_T_PENDING]            = UWB_DRP_REASON_PENDING,
		[UWB_RSV_STATE_T_DENIED]             = UWB_DRP_REASON_DENIED,
		[UWB_RSV_STATE_T_RESIZED]            = UWB_DRP_REASON_ACCEPTED,
		[UWB_RSV_STATE_T_EXPANDING_ACCEPTED] = UWB_DRP_REASON_ACCEPTED,
		[UWB_RSV_STATE_T_EXPANDING_CONFLICT] = UWB_DRP_REASON_CONFLICT,
		[UWB_RSV_STATE_T_EXPANDING_PENDING]  = UWB_DRP_REASON_PENDING,
		[UWB_RSV_STATE_T_EXPANDING_DENIED]   = UWB_DRP_REASON_DENIED,
	};

	return reason_codes[rsv->state];
}

/*
 * Return the reason code for a reservations's companion DRP IE .
 */
int uwb_rsv_companion_reason_code(struct uwb_rsv *rsv)
{
	static const int companion_reason_codes[] = {
		[UWB_RSV_STATE_O_MOVE_EXPANDING]     = UWB_DRP_REASON_ACCEPTED,
		[UWB_RSV_STATE_T_EXPANDING_ACCEPTED] = UWB_DRP_REASON_ACCEPTED,
		[UWB_RSV_STATE_T_EXPANDING_CONFLICT] = UWB_DRP_REASON_CONFLICT,
		[UWB_RSV_STATE_T_EXPANDING_PENDING]  = UWB_DRP_REASON_PENDING,
		[UWB_RSV_STATE_T_EXPANDING_DENIED]   = UWB_DRP_REASON_DENIED,
	};

	return companion_reason_codes[rsv->state];
}

/*
 * Return the status bit for a reservations's DRP IE.
 */
int uwb_rsv_status(struct uwb_rsv *rsv)
{
	static const int statuses[] = {
		[UWB_RSV_STATE_O_INITIATED]          = 0,
		[UWB_RSV_STATE_O_PENDING]            = 0,
		[UWB_RSV_STATE_O_MODIFIED]           = 1,
		[UWB_RSV_STATE_O_ESTABLISHED]        = 1,
		[UWB_RSV_STATE_O_TO_BE_MOVED]        = 0,
		[UWB_RSV_STATE_O_MOVE_COMBINING]     = 1,
		[UWB_RSV_STATE_O_MOVE_REDUCING]      = 1,
		[UWB_RSV_STATE_O_MOVE_EXPANDING]     = 1,
		[UWB_RSV_STATE_T_ACCEPTED]           = 1,
		[UWB_RSV_STATE_T_CONFLICT]           = 0,
		[UWB_RSV_STATE_T_PENDING]            = 0,
		[UWB_RSV_STATE_T_DENIED]             = 0,
		[UWB_RSV_STATE_T_RESIZED]            = 1,
		[UWB_RSV_STATE_T_EXPANDING_ACCEPTED] = 1,
		[UWB_RSV_STATE_T_EXPANDING_CONFLICT] = 1,
		[UWB_RSV_STATE_T_EXPANDING_PENDING]  = 1,
		[UWB_RSV_STATE_T_EXPANDING_DENIED]   = 1,

	};

	return statuses[rsv->state];
}

/*
 * Return the status bit for a reservations's companion DRP IE .
 */
int uwb_rsv_companion_status(struct uwb_rsv *rsv)
{
	static const int companion_statuses[] = {
		[UWB_RSV_STATE_O_MOVE_EXPANDING]     = 0,
		[UWB_RSV_STATE_T_EXPANDING_ACCEPTED] = 1,
		[UWB_RSV_STATE_T_EXPANDING_CONFLICT] = 0,
		[UWB_RSV_STATE_T_EXPANDING_PENDING]  = 0,
		[UWB_RSV_STATE_T_EXPANDING_DENIED]   = 0,
	};

	return companion_statuses[rsv->state];
}

/*
 * 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;

	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;
	}
	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 uwb_ie_drp *drp_ie;
	struct uwb_rsv_move *mv;
	int unsafe;

	if (rsv->state == UWB_RSV_STATE_NONE) {
		kfree(rsv->drp_ie);
		rsv->drp_ie = NULL;
		return 0;
	}
	
	unsafe = rsv->mas.unsafe ? 1 : 0;

	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_unsafe(drp_ie,       unsafe);
	uwb_ie_drp_set_tiebreaker(drp_ie,   rsv->tiebreaker);
	uwb_ie_drp_set_owner(drp_ie,        uwb_rsv_is_owner(rsv));
	uwb_ie_drp_set_status(drp_ie,       uwb_rsv_status(rsv));
	uwb_ie_drp_set_reason_code(drp_ie,  uwb_rsv_reason_code(rsv));
	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);

	if (uwb_rsv_has_two_drp_ies(rsv)) {
		mv = &rsv->mv; 
		if (mv->companion_drp_ie == NULL) {
			mv->companion_drp_ie = uwb_drp_ie_alloc();
			if (mv->companion_drp_ie == NULL)
				return -ENOMEM;
		}
		drp_ie = mv->companion_drp_ie;
		
		/* keep all the same configuration of the main drp_ie */
		memcpy(drp_ie, rsv->drp_ie, sizeof(struct uwb_ie_drp));
		

		/* FIXME: handle properly the unsafe bit */
		uwb_ie_drp_set_unsafe(drp_ie,       1);
		uwb_ie_drp_set_status(drp_ie,       uwb_rsv_companion_status(rsv));
		uwb_ie_drp_set_reason_code(drp_ie,  uwb_rsv_companion_reason_code(rsv));
	
		uwb_drp_ie_from_bm(drp_ie, &mv->companion_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;

	bitmap_zero(bm->bm, UWB_NUM_MAS);

	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);
		}
	}
}