1 // SPDX-License-Identifier: GPL-2.0-only
2
3 #include <linux/ethtool_netlink.h>
4 #include <linux/bitmap.h>
5 #include "netlink.h"
6 #include "bitset.h"
7
8 /* Some bitmaps are internally represented as an array of unsigned long, some
9 * as an array of u32 (some even as single u32 for now). To avoid the need of
10 * wrappers on caller side, we provide two set of functions: those with "32"
11 * suffix in their names expect u32 based bitmaps, those without it expect
12 * unsigned long bitmaps.
13 */
14
ethnl_lower_bits(unsigned int n)15 static u32 ethnl_lower_bits(unsigned int n)
16 {
17 return ~(u32)0 >> (32 - n % 32);
18 }
19
ethnl_upper_bits(unsigned int n)20 static u32 ethnl_upper_bits(unsigned int n)
21 {
22 return ~(u32)0 << (n % 32);
23 }
24
25 /**
26 * ethnl_bitmap32_clear() - Clear u32 based bitmap
27 * @dst: bitmap to clear
28 * @start: beginning of the interval
29 * @end: end of the interval
30 * @mod: set if bitmap was modified
31 *
32 * Clear @nbits bits of a bitmap with indices @start <= i < @end
33 */
ethnl_bitmap32_clear(u32 * dst,unsigned int start,unsigned int end,bool * mod)34 static void ethnl_bitmap32_clear(u32 *dst, unsigned int start, unsigned int end,
35 bool *mod)
36 {
37 unsigned int start_word = start / 32;
38 unsigned int end_word = end / 32;
39 unsigned int i;
40 u32 mask;
41
42 if (end <= start)
43 return;
44
45 if (start % 32) {
46 mask = ethnl_upper_bits(start);
47 if (end_word == start_word) {
48 mask &= ethnl_lower_bits(end);
49 if (dst[start_word] & mask) {
50 dst[start_word] &= ~mask;
51 *mod = true;
52 }
53 return;
54 }
55 if (dst[start_word] & mask) {
56 dst[start_word] &= ~mask;
57 *mod = true;
58 }
59 start_word++;
60 }
61
62 for (i = start_word; i < end_word; i++) {
63 if (dst[i]) {
64 dst[i] = 0;
65 *mod = true;
66 }
67 }
68 if (end % 32) {
69 mask = ethnl_lower_bits(end);
70 if (dst[end_word] & mask) {
71 dst[end_word] &= ~mask;
72 *mod = true;
73 }
74 }
75 }
76
77 /**
78 * ethnl_bitmap32_not_zero() - Check if any bit is set in an interval
79 * @map: bitmap to test
80 * @start: beginning of the interval
81 * @end: end of the interval
82 *
83 * Return: true if there is non-zero bit with index @start <= i < @end,
84 * false if the whole interval is zero
85 */
ethnl_bitmap32_not_zero(const u32 * map,unsigned int start,unsigned int end)86 static bool ethnl_bitmap32_not_zero(const u32 *map, unsigned int start,
87 unsigned int end)
88 {
89 unsigned int start_word = start / 32;
90 unsigned int end_word = end / 32;
91 u32 mask;
92
93 if (end <= start)
94 return true;
95
96 if (start % 32) {
97 mask = ethnl_upper_bits(start);
98 if (end_word == start_word) {
99 mask &= ethnl_lower_bits(end);
100 return map[start_word] & mask;
101 }
102 if (map[start_word] & mask)
103 return true;
104 start_word++;
105 }
106
107 if (!memchr_inv(map + start_word, '\0',
108 (end_word - start_word) * sizeof(u32)))
109 return true;
110 if (end % 32 == 0)
111 return true;
112 return map[end_word] & ethnl_lower_bits(end);
113 }
114
115 /**
116 * ethnl_bitmap32_update() - Modify u32 based bitmap according to value/mask
117 * pair
118 * @dst: bitmap to update
119 * @nbits: bit size of the bitmap
120 * @value: values to set
121 * @mask: mask of bits to set
122 * @mod: set to true if bitmap is modified, preserve if not
123 *
124 * Set bits in @dst bitmap which are set in @mask to values from @value, leave
125 * the rest untouched. If destination bitmap was modified, set @mod to true,
126 * leave as it is if not.
127 */
ethnl_bitmap32_update(u32 * dst,unsigned int nbits,const u32 * value,const u32 * mask,bool * mod)128 static void ethnl_bitmap32_update(u32 *dst, unsigned int nbits,
129 const u32 *value, const u32 *mask, bool *mod)
130 {
131 while (nbits > 0) {
132 u32 real_mask = mask ? *mask : ~(u32)0;
133 u32 new_value;
134
135 if (nbits < 32)
136 real_mask &= ethnl_lower_bits(nbits);
137 new_value = (*dst & ~real_mask) | (*value & real_mask);
138 if (new_value != *dst) {
139 *dst = new_value;
140 *mod = true;
141 }
142
143 if (nbits <= 32)
144 break;
145 dst++;
146 nbits -= 32;
147 value++;
148 if (mask)
149 mask++;
150 }
151 }
152
ethnl_bitmap32_test_bit(const u32 * map,unsigned int index)153 static bool ethnl_bitmap32_test_bit(const u32 *map, unsigned int index)
154 {
155 return map[index / 32] & (1U << (index % 32));
156 }
157
158 /**
159 * ethnl_bitset32_size() - Calculate size of bitset nested attribute
160 * @val: value bitmap (u32 based)
161 * @mask: mask bitmap (u32 based, optional)
162 * @nbits: bit length of the bitset
163 * @names: array of bit names (optional)
164 * @compact: assume compact format for output
165 *
166 * Estimate length of netlink attribute composed by a later call to
167 * ethnl_put_bitset32() call with the same arguments.
168 *
169 * Return: negative error code or attribute length estimate
170 */
ethnl_bitset32_size(const u32 * val,const u32 * mask,unsigned int nbits,ethnl_string_array_t names,bool compact)171 int ethnl_bitset32_size(const u32 *val, const u32 *mask, unsigned int nbits,
172 ethnl_string_array_t names, bool compact)
173 {
174 unsigned int len = 0;
175
176 /* list flag */
177 if (!mask)
178 len += nla_total_size(sizeof(u32));
179 /* size */
180 len += nla_total_size(sizeof(u32));
181
182 if (compact) {
183 unsigned int nwords = DIV_ROUND_UP(nbits, 32);
184
185 /* value, mask */
186 len += (mask ? 2 : 1) * nla_total_size(nwords * sizeof(u32));
187 } else {
188 unsigned int bits_len = 0;
189 unsigned int bit_len, i;
190
191 for (i = 0; i < nbits; i++) {
192 const char *name = names ? names[i] : NULL;
193
194 if (!ethnl_bitmap32_test_bit(mask ?: val, i))
195 continue;
196 /* index */
197 bit_len = nla_total_size(sizeof(u32));
198 /* name */
199 if (name)
200 bit_len += ethnl_strz_size(name);
201 /* value */
202 if (mask && ethnl_bitmap32_test_bit(val, i))
203 bit_len += nla_total_size(0);
204
205 /* bit nest */
206 bits_len += nla_total_size(bit_len);
207 }
208 /* bits nest */
209 len += nla_total_size(bits_len);
210 }
211
212 /* outermost nest */
213 return nla_total_size(len);
214 }
215
216 /**
217 * ethnl_put_bitset32() - Put a bitset nest into a message
218 * @skb: skb with the message
219 * @attrtype: attribute type for the bitset nest
220 * @val: value bitmap (u32 based)
221 * @mask: mask bitmap (u32 based, optional)
222 * @nbits: bit length of the bitset
223 * @names: array of bit names (optional)
224 * @compact: use compact format for the output
225 *
226 * Compose a nested attribute representing a bitset. If @mask is null, simple
227 * bitmap (bit list) is created, if @mask is provided, represent a value/mask
228 * pair. Bit names are only used in verbose mode and when provided by calller.
229 *
230 * Return: 0 on success, negative error value on error
231 */
ethnl_put_bitset32(struct sk_buff * skb,int attrtype,const u32 * val,const u32 * mask,unsigned int nbits,ethnl_string_array_t names,bool compact)232 int ethnl_put_bitset32(struct sk_buff *skb, int attrtype, const u32 *val,
233 const u32 *mask, unsigned int nbits,
234 ethnl_string_array_t names, bool compact)
235 {
236 struct nlattr *nest;
237 struct nlattr *attr;
238
239 nest = nla_nest_start(skb, attrtype);
240 if (!nest)
241 return -EMSGSIZE;
242
243 if (!mask && nla_put_flag(skb, ETHTOOL_A_BITSET_NOMASK))
244 goto nla_put_failure;
245 if (nla_put_u32(skb, ETHTOOL_A_BITSET_SIZE, nbits))
246 goto nla_put_failure;
247 if (compact) {
248 unsigned int nwords = DIV_ROUND_UP(nbits, 32);
249 unsigned int nbytes = nwords * sizeof(u32);
250 u32 *dst;
251
252 attr = nla_reserve(skb, ETHTOOL_A_BITSET_VALUE, nbytes);
253 if (!attr)
254 goto nla_put_failure;
255 dst = nla_data(attr);
256 memcpy(dst, val, nbytes);
257 if (nbits % 32)
258 dst[nwords - 1] &= ethnl_lower_bits(nbits);
259
260 if (mask) {
261 attr = nla_reserve(skb, ETHTOOL_A_BITSET_MASK, nbytes);
262 if (!attr)
263 goto nla_put_failure;
264 dst = nla_data(attr);
265 memcpy(dst, mask, nbytes);
266 if (nbits % 32)
267 dst[nwords - 1] &= ethnl_lower_bits(nbits);
268 }
269 } else {
270 struct nlattr *bits;
271 unsigned int i;
272
273 bits = nla_nest_start(skb, ETHTOOL_A_BITSET_BITS);
274 if (!bits)
275 goto nla_put_failure;
276 for (i = 0; i < nbits; i++) {
277 const char *name = names ? names[i] : NULL;
278
279 if (!ethnl_bitmap32_test_bit(mask ?: val, i))
280 continue;
281 attr = nla_nest_start(skb, ETHTOOL_A_BITSET_BITS_BIT);
282 if (!attr)
283 goto nla_put_failure;
284 if (nla_put_u32(skb, ETHTOOL_A_BITSET_BIT_INDEX, i))
285 goto nla_put_failure;
286 if (name &&
287 ethnl_put_strz(skb, ETHTOOL_A_BITSET_BIT_NAME, name))
288 goto nla_put_failure;
289 if (mask && ethnl_bitmap32_test_bit(val, i) &&
290 nla_put_flag(skb, ETHTOOL_A_BITSET_BIT_VALUE))
291 goto nla_put_failure;
292 nla_nest_end(skb, attr);
293 }
294 nla_nest_end(skb, bits);
295 }
296
297 nla_nest_end(skb, nest);
298 return 0;
299
300 nla_put_failure:
301 nla_nest_cancel(skb, nest);
302 return -EMSGSIZE;
303 }
304
305 static const struct nla_policy bitset_policy[] = {
306 [ETHTOOL_A_BITSET_NOMASK] = { .type = NLA_FLAG },
307 [ETHTOOL_A_BITSET_SIZE] = NLA_POLICY_MAX(NLA_U32,
308 ETHNL_MAX_BITSET_SIZE),
309 [ETHTOOL_A_BITSET_BITS] = { .type = NLA_NESTED },
310 [ETHTOOL_A_BITSET_VALUE] = { .type = NLA_BINARY },
311 [ETHTOOL_A_BITSET_MASK] = { .type = NLA_BINARY },
312 };
313
314 static const struct nla_policy bit_policy[] = {
315 [ETHTOOL_A_BITSET_BIT_INDEX] = { .type = NLA_U32 },
316 [ETHTOOL_A_BITSET_BIT_NAME] = { .type = NLA_NUL_STRING },
317 [ETHTOOL_A_BITSET_BIT_VALUE] = { .type = NLA_FLAG },
318 };
319
320 /**
321 * ethnl_bitset_is_compact() - check if bitset attribute represents a compact
322 * bitset
323 * @bitset: nested attribute representing a bitset
324 * @compact: pointer for return value
325 *
326 * Return: 0 on success, negative error code on failure
327 */
ethnl_bitset_is_compact(const struct nlattr * bitset,bool * compact)328 int ethnl_bitset_is_compact(const struct nlattr *bitset, bool *compact)
329 {
330 struct nlattr *tb[ARRAY_SIZE(bitset_policy)];
331 int ret;
332
333 ret = nla_parse_nested(tb, ARRAY_SIZE(bitset_policy) - 1, bitset,
334 bitset_policy, NULL);
335 if (ret < 0)
336 return ret;
337
338 if (tb[ETHTOOL_A_BITSET_BITS]) {
339 if (tb[ETHTOOL_A_BITSET_VALUE] || tb[ETHTOOL_A_BITSET_MASK])
340 return -EINVAL;
341 *compact = false;
342 return 0;
343 }
344 if (!tb[ETHTOOL_A_BITSET_SIZE] || !tb[ETHTOOL_A_BITSET_VALUE])
345 return -EINVAL;
346
347 *compact = true;
348 return 0;
349 }
350
351 /**
352 * ethnl_name_to_idx() - look up string index for a name
353 * @names: array of ETH_GSTRING_LEN sized strings
354 * @n_names: number of strings in the array
355 * @name: name to look up
356 *
357 * Return: index of the string if found, -ENOENT if not found
358 */
ethnl_name_to_idx(ethnl_string_array_t names,unsigned int n_names,const char * name)359 static int ethnl_name_to_idx(ethnl_string_array_t names, unsigned int n_names,
360 const char *name)
361 {
362 unsigned int i;
363
364 if (!names)
365 return -ENOENT;
366
367 for (i = 0; i < n_names; i++) {
368 /* names[i] may not be null terminated */
369 if (!strncmp(names[i], name, ETH_GSTRING_LEN) &&
370 strlen(name) <= ETH_GSTRING_LEN)
371 return i;
372 }
373
374 return -ENOENT;
375 }
376
ethnl_parse_bit(unsigned int * index,bool * val,unsigned int nbits,const struct nlattr * bit_attr,bool no_mask,ethnl_string_array_t names,struct netlink_ext_ack * extack)377 static int ethnl_parse_bit(unsigned int *index, bool *val, unsigned int nbits,
378 const struct nlattr *bit_attr, bool no_mask,
379 ethnl_string_array_t names,
380 struct netlink_ext_ack *extack)
381 {
382 struct nlattr *tb[ARRAY_SIZE(bit_policy)];
383 int ret, idx;
384
385 ret = nla_parse_nested(tb, ARRAY_SIZE(bit_policy) - 1, bit_attr,
386 bit_policy, extack);
387 if (ret < 0)
388 return ret;
389
390 if (tb[ETHTOOL_A_BITSET_BIT_INDEX]) {
391 const char *name;
392
393 idx = nla_get_u32(tb[ETHTOOL_A_BITSET_BIT_INDEX]);
394 if (idx >= nbits) {
395 NL_SET_ERR_MSG_ATTR(extack,
396 tb[ETHTOOL_A_BITSET_BIT_INDEX],
397 "bit index too high");
398 return -EOPNOTSUPP;
399 }
400 name = names ? names[idx] : NULL;
401 if (tb[ETHTOOL_A_BITSET_BIT_NAME] && name &&
402 strncmp(nla_data(tb[ETHTOOL_A_BITSET_BIT_NAME]), name,
403 nla_len(tb[ETHTOOL_A_BITSET_BIT_NAME]))) {
404 NL_SET_ERR_MSG_ATTR(extack, bit_attr,
405 "bit index and name mismatch");
406 return -EINVAL;
407 }
408 } else if (tb[ETHTOOL_A_BITSET_BIT_NAME]) {
409 idx = ethnl_name_to_idx(names, nbits,
410 nla_data(tb[ETHTOOL_A_BITSET_BIT_NAME]));
411 if (idx < 0) {
412 NL_SET_ERR_MSG_ATTR(extack,
413 tb[ETHTOOL_A_BITSET_BIT_NAME],
414 "bit name not found");
415 return -EOPNOTSUPP;
416 }
417 } else {
418 NL_SET_ERR_MSG_ATTR(extack, bit_attr,
419 "neither bit index nor name specified");
420 return -EINVAL;
421 }
422
423 *index = idx;
424 *val = no_mask || tb[ETHTOOL_A_BITSET_BIT_VALUE];
425 return 0;
426 }
427
428 static int
ethnl_update_bitset32_verbose(u32 * bitmap,unsigned int nbits,const struct nlattr * attr,struct nlattr ** tb,ethnl_string_array_t names,struct netlink_ext_ack * extack,bool * mod)429 ethnl_update_bitset32_verbose(u32 *bitmap, unsigned int nbits,
430 const struct nlattr *attr, struct nlattr **tb,
431 ethnl_string_array_t names,
432 struct netlink_ext_ack *extack, bool *mod)
433 {
434 struct nlattr *bit_attr;
435 bool no_mask;
436 int rem;
437 int ret;
438
439 if (tb[ETHTOOL_A_BITSET_VALUE]) {
440 NL_SET_ERR_MSG_ATTR(extack, tb[ETHTOOL_A_BITSET_VALUE],
441 "value only allowed in compact bitset");
442 return -EINVAL;
443 }
444 if (tb[ETHTOOL_A_BITSET_MASK]) {
445 NL_SET_ERR_MSG_ATTR(extack, tb[ETHTOOL_A_BITSET_MASK],
446 "mask only allowed in compact bitset");
447 return -EINVAL;
448 }
449
450 no_mask = tb[ETHTOOL_A_BITSET_NOMASK];
451 if (no_mask)
452 ethnl_bitmap32_clear(bitmap, 0, nbits, mod);
453
454 nla_for_each_nested(bit_attr, tb[ETHTOOL_A_BITSET_BITS], rem) {
455 bool old_val, new_val;
456 unsigned int idx;
457
458 if (nla_type(bit_attr) != ETHTOOL_A_BITSET_BITS_BIT) {
459 NL_SET_ERR_MSG_ATTR(extack, bit_attr,
460 "only ETHTOOL_A_BITSET_BITS_BIT allowed in ETHTOOL_A_BITSET_BITS");
461 return -EINVAL;
462 }
463 ret = ethnl_parse_bit(&idx, &new_val, nbits, bit_attr, no_mask,
464 names, extack);
465 if (ret < 0)
466 return ret;
467 old_val = bitmap[idx / 32] & ((u32)1 << (idx % 32));
468 if (new_val != old_val) {
469 if (new_val)
470 bitmap[idx / 32] |= ((u32)1 << (idx % 32));
471 else
472 bitmap[idx / 32] &= ~((u32)1 << (idx % 32));
473 *mod = true;
474 }
475 }
476
477 return 0;
478 }
479
ethnl_compact_sanity_checks(unsigned int nbits,const struct nlattr * nest,struct nlattr ** tb,struct netlink_ext_ack * extack)480 static int ethnl_compact_sanity_checks(unsigned int nbits,
481 const struct nlattr *nest,
482 struct nlattr **tb,
483 struct netlink_ext_ack *extack)
484 {
485 bool no_mask = tb[ETHTOOL_A_BITSET_NOMASK];
486 unsigned int attr_nbits, attr_nwords;
487 const struct nlattr *test_attr;
488
489 if (no_mask && tb[ETHTOOL_A_BITSET_MASK]) {
490 NL_SET_ERR_MSG_ATTR(extack, tb[ETHTOOL_A_BITSET_MASK],
491 "mask not allowed in list bitset");
492 return -EINVAL;
493 }
494 if (!tb[ETHTOOL_A_BITSET_SIZE]) {
495 NL_SET_ERR_MSG_ATTR(extack, nest,
496 "missing size in compact bitset");
497 return -EINVAL;
498 }
499 if (!tb[ETHTOOL_A_BITSET_VALUE]) {
500 NL_SET_ERR_MSG_ATTR(extack, nest,
501 "missing value in compact bitset");
502 return -EINVAL;
503 }
504 if (!no_mask && !tb[ETHTOOL_A_BITSET_MASK]) {
505 NL_SET_ERR_MSG_ATTR(extack, nest,
506 "missing mask in compact nonlist bitset");
507 return -EINVAL;
508 }
509
510 attr_nbits = nla_get_u32(tb[ETHTOOL_A_BITSET_SIZE]);
511 attr_nwords = DIV_ROUND_UP(attr_nbits, 32);
512 if (nla_len(tb[ETHTOOL_A_BITSET_VALUE]) != attr_nwords * sizeof(u32)) {
513 NL_SET_ERR_MSG_ATTR(extack, tb[ETHTOOL_A_BITSET_VALUE],
514 "bitset value length does not match size");
515 return -EINVAL;
516 }
517 if (tb[ETHTOOL_A_BITSET_MASK] &&
518 nla_len(tb[ETHTOOL_A_BITSET_MASK]) != attr_nwords * sizeof(u32)) {
519 NL_SET_ERR_MSG_ATTR(extack, tb[ETHTOOL_A_BITSET_MASK],
520 "bitset mask length does not match size");
521 return -EINVAL;
522 }
523 if (attr_nbits <= nbits)
524 return 0;
525
526 test_attr = no_mask ? tb[ETHTOOL_A_BITSET_VALUE] :
527 tb[ETHTOOL_A_BITSET_MASK];
528 if (ethnl_bitmap32_not_zero(nla_data(test_attr), nbits, attr_nbits)) {
529 NL_SET_ERR_MSG_ATTR(extack, test_attr,
530 "cannot modify bits past kernel bitset size");
531 return -EINVAL;
532 }
533 return 0;
534 }
535
536 /**
537 * ethnl_update_bitset32() - Apply a bitset nest to a u32 based bitmap
538 * @bitmap: bitmap to update
539 * @nbits: size of the updated bitmap in bits
540 * @attr: nest attribute to parse and apply
541 * @names: array of bit names; may be null for compact format
542 * @extack: extack for error reporting
543 * @mod: set this to true if bitmap is modified, leave as it is if not
544 *
545 * Apply bitset netsted attribute to a bitmap. If the attribute represents
546 * a bit list, @bitmap is set to its contents; otherwise, bits in mask are
547 * set to values from value. Bitmaps in the attribute may be longer than
548 * @nbits but the message must not request modifying any bits past @nbits.
549 *
550 * Return: negative error code on failure, 0 on success
551 */
ethnl_update_bitset32(u32 * bitmap,unsigned int nbits,const struct nlattr * attr,ethnl_string_array_t names,struct netlink_ext_ack * extack,bool * mod)552 int ethnl_update_bitset32(u32 *bitmap, unsigned int nbits,
553 const struct nlattr *attr, ethnl_string_array_t names,
554 struct netlink_ext_ack *extack, bool *mod)
555 {
556 struct nlattr *tb[ARRAY_SIZE(bitset_policy)];
557 unsigned int change_bits;
558 bool no_mask;
559 int ret;
560
561 if (!attr)
562 return 0;
563 ret = nla_parse_nested(tb, ARRAY_SIZE(bitset_policy) - 1, attr,
564 bitset_policy, extack);
565 if (ret < 0)
566 return ret;
567
568 if (tb[ETHTOOL_A_BITSET_BITS])
569 return ethnl_update_bitset32_verbose(bitmap, nbits, attr, tb,
570 names, extack, mod);
571 ret = ethnl_compact_sanity_checks(nbits, attr, tb, extack);
572 if (ret < 0)
573 return ret;
574
575 no_mask = tb[ETHTOOL_A_BITSET_NOMASK];
576 change_bits = min_t(unsigned int,
577 nla_get_u32(tb[ETHTOOL_A_BITSET_SIZE]), nbits);
578 ethnl_bitmap32_update(bitmap, change_bits,
579 nla_data(tb[ETHTOOL_A_BITSET_VALUE]),
580 no_mask ? NULL :
581 nla_data(tb[ETHTOOL_A_BITSET_MASK]),
582 mod);
583 if (no_mask && change_bits < nbits)
584 ethnl_bitmap32_clear(bitmap, change_bits, nbits, mod);
585
586 return 0;
587 }
588
589 /**
590 * ethnl_parse_bitset() - Compute effective value and mask from bitset nest
591 * @val: unsigned long based bitmap to put value into
592 * @mask: unsigned long based bitmap to put mask into
593 * @nbits: size of @val and @mask bitmaps
594 * @attr: nest attribute to parse and apply
595 * @names: array of bit names; may be null for compact format
596 * @extack: extack for error reporting
597 *
598 * Provide @nbits size long bitmaps for value and mask so that
599 * x = (val & mask) | (x & ~mask) would modify any @nbits sized bitmap x
600 * the same way ethnl_update_bitset() with the same bitset attribute would.
601 *
602 * Return: negative error code on failure, 0 on success
603 */
ethnl_parse_bitset(unsigned long * val,unsigned long * mask,unsigned int nbits,const struct nlattr * attr,ethnl_string_array_t names,struct netlink_ext_ack * extack)604 int ethnl_parse_bitset(unsigned long *val, unsigned long *mask,
605 unsigned int nbits, const struct nlattr *attr,
606 ethnl_string_array_t names,
607 struct netlink_ext_ack *extack)
608 {
609 struct nlattr *tb[ARRAY_SIZE(bitset_policy)];
610 const struct nlattr *bit_attr;
611 bool no_mask;
612 int rem;
613 int ret;
614
615 if (!attr)
616 return 0;
617 ret = nla_parse_nested(tb, ARRAY_SIZE(bitset_policy) - 1, attr,
618 bitset_policy, extack);
619 if (ret < 0)
620 return ret;
621 no_mask = tb[ETHTOOL_A_BITSET_NOMASK];
622
623 if (!tb[ETHTOOL_A_BITSET_BITS]) {
624 unsigned int change_bits;
625
626 ret = ethnl_compact_sanity_checks(nbits, attr, tb, extack);
627 if (ret < 0)
628 return ret;
629
630 change_bits = nla_get_u32(tb[ETHTOOL_A_BITSET_SIZE]);
631 if (change_bits > nbits)
632 change_bits = nbits;
633 bitmap_from_arr32(val, nla_data(tb[ETHTOOL_A_BITSET_VALUE]),
634 change_bits);
635 if (change_bits < nbits)
636 bitmap_clear(val, change_bits, nbits - change_bits);
637 if (no_mask) {
638 bitmap_fill(mask, nbits);
639 } else {
640 bitmap_from_arr32(mask,
641 nla_data(tb[ETHTOOL_A_BITSET_MASK]),
642 change_bits);
643 if (change_bits < nbits)
644 bitmap_clear(mask, change_bits,
645 nbits - change_bits);
646 }
647
648 return 0;
649 }
650
651 if (tb[ETHTOOL_A_BITSET_VALUE]) {
652 NL_SET_ERR_MSG_ATTR(extack, tb[ETHTOOL_A_BITSET_VALUE],
653 "value only allowed in compact bitset");
654 return -EINVAL;
655 }
656 if (tb[ETHTOOL_A_BITSET_MASK]) {
657 NL_SET_ERR_MSG_ATTR(extack, tb[ETHTOOL_A_BITSET_MASK],
658 "mask only allowed in compact bitset");
659 return -EINVAL;
660 }
661
662 bitmap_zero(val, nbits);
663 if (no_mask)
664 bitmap_fill(mask, nbits);
665 else
666 bitmap_zero(mask, nbits);
667
668 nla_for_each_nested(bit_attr, tb[ETHTOOL_A_BITSET_BITS], rem) {
669 unsigned int idx;
670 bool bit_val;
671
672 ret = ethnl_parse_bit(&idx, &bit_val, nbits, bit_attr, no_mask,
673 names, extack);
674 if (ret < 0)
675 return ret;
676 if (bit_val)
677 __set_bit(idx, val);
678 if (!no_mask)
679 __set_bit(idx, mask);
680 }
681
682 return 0;
683 }
684
685 #if BITS_PER_LONG == 64 && defined(__BIG_ENDIAN)
686
687 /* 64-bit big endian architectures are the only case when u32 based bitmaps
688 * and unsigned long based bitmaps have different memory layout so that we
689 * cannot simply cast the latter to the former and need actual wrappers
690 * converting the latter to the former.
691 *
692 * To reduce the number of slab allocations, the wrappers use fixed size local
693 * variables for bitmaps up to ETHNL_SMALL_BITMAP_BITS bits which is the
694 * majority of bitmaps used by ethtool.
695 */
696 #define ETHNL_SMALL_BITMAP_BITS 128
697 #define ETHNL_SMALL_BITMAP_WORDS DIV_ROUND_UP(ETHNL_SMALL_BITMAP_BITS, 32)
698
ethnl_bitset_size(const unsigned long * val,const unsigned long * mask,unsigned int nbits,ethnl_string_array_t names,bool compact)699 int ethnl_bitset_size(const unsigned long *val, const unsigned long *mask,
700 unsigned int nbits, ethnl_string_array_t names,
701 bool compact)
702 {
703 u32 small_mask32[ETHNL_SMALL_BITMAP_WORDS];
704 u32 small_val32[ETHNL_SMALL_BITMAP_WORDS];
705 u32 *mask32;
706 u32 *val32;
707 int ret;
708
709 if (nbits > ETHNL_SMALL_BITMAP_BITS) {
710 unsigned int nwords = DIV_ROUND_UP(nbits, 32);
711
712 val32 = kmalloc_array(2 * nwords, sizeof(u32), GFP_KERNEL);
713 if (!val32)
714 return -ENOMEM;
715 mask32 = val32 + nwords;
716 } else {
717 val32 = small_val32;
718 mask32 = small_mask32;
719 }
720
721 bitmap_to_arr32(val32, val, nbits);
722 if (mask)
723 bitmap_to_arr32(mask32, mask, nbits);
724 else
725 mask32 = NULL;
726 ret = ethnl_bitset32_size(val32, mask32, nbits, names, compact);
727
728 if (nbits > ETHNL_SMALL_BITMAP_BITS)
729 kfree(val32);
730
731 return ret;
732 }
733
ethnl_put_bitset(struct sk_buff * skb,int attrtype,const unsigned long * val,const unsigned long * mask,unsigned int nbits,ethnl_string_array_t names,bool compact)734 int ethnl_put_bitset(struct sk_buff *skb, int attrtype,
735 const unsigned long *val, const unsigned long *mask,
736 unsigned int nbits, ethnl_string_array_t names,
737 bool compact)
738 {
739 u32 small_mask32[ETHNL_SMALL_BITMAP_WORDS];
740 u32 small_val32[ETHNL_SMALL_BITMAP_WORDS];
741 u32 *mask32;
742 u32 *val32;
743 int ret;
744
745 if (nbits > ETHNL_SMALL_BITMAP_BITS) {
746 unsigned int nwords = DIV_ROUND_UP(nbits, 32);
747
748 val32 = kmalloc_array(2 * nwords, sizeof(u32), GFP_KERNEL);
749 if (!val32)
750 return -ENOMEM;
751 mask32 = val32 + nwords;
752 } else {
753 val32 = small_val32;
754 mask32 = small_mask32;
755 }
756
757 bitmap_to_arr32(val32, val, nbits);
758 if (mask)
759 bitmap_to_arr32(mask32, mask, nbits);
760 else
761 mask32 = NULL;
762 ret = ethnl_put_bitset32(skb, attrtype, val32, mask32, nbits, names,
763 compact);
764
765 if (nbits > ETHNL_SMALL_BITMAP_BITS)
766 kfree(val32);
767
768 return ret;
769 }
770
ethnl_update_bitset(unsigned long * bitmap,unsigned int nbits,const struct nlattr * attr,ethnl_string_array_t names,struct netlink_ext_ack * extack,bool * mod)771 int ethnl_update_bitset(unsigned long *bitmap, unsigned int nbits,
772 const struct nlattr *attr, ethnl_string_array_t names,
773 struct netlink_ext_ack *extack, bool *mod)
774 {
775 u32 small_bitmap32[ETHNL_SMALL_BITMAP_WORDS];
776 u32 *bitmap32 = small_bitmap32;
777 bool u32_mod = false;
778 int ret;
779
780 if (nbits > ETHNL_SMALL_BITMAP_BITS) {
781 unsigned int dst_words = DIV_ROUND_UP(nbits, 32);
782
783 bitmap32 = kmalloc_array(dst_words, sizeof(u32), GFP_KERNEL);
784 if (!bitmap32)
785 return -ENOMEM;
786 }
787
788 bitmap_to_arr32(bitmap32, bitmap, nbits);
789 ret = ethnl_update_bitset32(bitmap32, nbits, attr, names, extack,
790 &u32_mod);
791 if (u32_mod) {
792 bitmap_from_arr32(bitmap, bitmap32, nbits);
793 *mod = true;
794 }
795
796 if (nbits > ETHNL_SMALL_BITMAP_BITS)
797 kfree(bitmap32);
798
799 return ret;
800 }
801
802 #else
803
804 /* On little endian 64-bit and all 32-bit architectures, an unsigned long
805 * based bitmap can be interpreted as u32 based one using a simple cast.
806 */
807
ethnl_bitset_size(const unsigned long * val,const unsigned long * mask,unsigned int nbits,ethnl_string_array_t names,bool compact)808 int ethnl_bitset_size(const unsigned long *val, const unsigned long *mask,
809 unsigned int nbits, ethnl_string_array_t names,
810 bool compact)
811 {
812 return ethnl_bitset32_size((const u32 *)val, (const u32 *)mask, nbits,
813 names, compact);
814 }
815
ethnl_put_bitset(struct sk_buff * skb,int attrtype,const unsigned long * val,const unsigned long * mask,unsigned int nbits,ethnl_string_array_t names,bool compact)816 int ethnl_put_bitset(struct sk_buff *skb, int attrtype,
817 const unsigned long *val, const unsigned long *mask,
818 unsigned int nbits, ethnl_string_array_t names,
819 bool compact)
820 {
821 return ethnl_put_bitset32(skb, attrtype, (const u32 *)val,
822 (const u32 *)mask, nbits, names, compact);
823 }
824
ethnl_update_bitset(unsigned long * bitmap,unsigned int nbits,const struct nlattr * attr,ethnl_string_array_t names,struct netlink_ext_ack * extack,bool * mod)825 int ethnl_update_bitset(unsigned long *bitmap, unsigned int nbits,
826 const struct nlattr *attr, ethnl_string_array_t names,
827 struct netlink_ext_ack *extack, bool *mod)
828 {
829 return ethnl_update_bitset32((u32 *)bitmap, nbits, attr, names, extack,
830 mod);
831 }
832
833 #endif /* BITS_PER_LONG == 64 && defined(__BIG_ENDIAN) */
834