1 // SPDX-License-Identifier: GPL-2.0-only
3 #include <linux/ethtool_netlink.h>
4 #include <linux/bitmap.h>
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.
15 static u32 ethnl_lower_bits(unsigned int n)
17 return ~(u32)0 >> (32 - n % 32);
20 static u32 ethnl_upper_bits(unsigned int n)
22 return ~(u32)0 << (n % 32);
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
32 * Clear @nbits bits of a bitmap with indices @start <= i < @end
34 static void ethnl_bitmap32_clear(u32 *dst, unsigned int start, unsigned int end,
37 unsigned int start_word = start / 32;
38 unsigned int end_word = end / 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;
55 if (dst[start_word] & mask) {
56 dst[start_word] &= ~mask;
62 for (i = start_word; i < end_word; i++) {
69 mask = ethnl_lower_bits(end);
70 if (dst[end_word] & mask) {
71 dst[end_word] &= ~mask;
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
83 * Return: true if there is non-zero bit with index @start <= i < @end,
84 * false if the whole interval is zero
86 static bool ethnl_bitmap32_not_zero(const u32 *map, unsigned int start,
89 unsigned int start_word = start / 32;
90 unsigned int end_word = end / 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;
102 if (map[start_word] & mask)
107 if (!memchr_inv(map + start_word, '\0',
108 (end_word - start_word) * sizeof(u32)))
112 return map[end_word] & ethnl_lower_bits(end);
116 * ethnl_bitmap32_update() - Modify u32 based bitmap according to value/mask
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
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.
128 static void ethnl_bitmap32_update(u32 *dst, unsigned int nbits,
129 const u32 *value, const u32 *mask, bool *mod)
132 u32 real_mask = mask ? *mask : ~(u32)0;
136 real_mask &= ethnl_lower_bits(nbits);
137 new_value = (*dst & ~real_mask) | (*value & real_mask);
138 if (new_value != *dst) {
153 static bool ethnl_bitmap32_test_bit(const u32 *map, unsigned int index)
155 return map[index / 32] & (1U << (index % 32));
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
166 * Estimate length of netlink attribute composed by a later call to
167 * ethnl_put_bitset32() call with the same arguments.
169 * Return: negative error code or attribute length estimate
171 int ethnl_bitset32_size(const u32 *val, const u32 *mask, unsigned int nbits,
172 ethnl_string_array_t names, bool compact)
174 unsigned int len = 0;
178 len += nla_total_size(sizeof(u32));
180 len += nla_total_size(sizeof(u32));
183 unsigned int nwords = DIV_ROUND_UP(nbits, 32);
186 len += (mask ? 2 : 1) * nla_total_size(nwords * sizeof(u32));
188 unsigned int bits_len = 0;
189 unsigned int bit_len, i;
191 for (i = 0; i < nbits; i++) {
192 const char *name = names ? names[i] : NULL;
194 if (!ethnl_bitmap32_test_bit(mask ?: val, i))
197 bit_len = nla_total_size(sizeof(u32));
200 bit_len += ethnl_strz_size(name);
202 if (mask && ethnl_bitmap32_test_bit(val, i))
203 bit_len += nla_total_size(0);
206 bits_len += nla_total_size(bit_len);
209 len += nla_total_size(bits_len);
213 return nla_total_size(len);
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
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.
230 * Return: 0 on success, negative error value on error
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)
239 nest = nla_nest_start(skb, attrtype);
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;
248 unsigned int nwords = DIV_ROUND_UP(nbits, 32);
249 unsigned int nbytes = nwords * sizeof(u32);
252 attr = nla_reserve(skb, ETHTOOL_A_BITSET_VALUE, nbytes);
254 goto nla_put_failure;
255 dst = nla_data(attr);
256 memcpy(dst, val, nbytes);
258 dst[nwords - 1] &= ethnl_lower_bits(nbits);
261 attr = nla_reserve(skb, ETHTOOL_A_BITSET_MASK, nbytes);
263 goto nla_put_failure;
264 dst = nla_data(attr);
265 memcpy(dst, mask, nbytes);
267 dst[nwords - 1] &= ethnl_lower_bits(nbits);
273 bits = nla_nest_start(skb, ETHTOOL_A_BITSET_BITS);
275 goto nla_put_failure;
276 for (i = 0; i < nbits; i++) {
277 const char *name = names ? names[i] : NULL;
279 if (!ethnl_bitmap32_test_bit(mask ?: val, i))
281 attr = nla_nest_start(skb, ETHTOOL_A_BITSET_BITS_BIT);
283 goto nla_put_failure;
284 if (nla_put_u32(skb, ETHTOOL_A_BITSET_BIT_INDEX, i))
285 goto nla_put_failure;
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);
294 nla_nest_end(skb, bits);
297 nla_nest_end(skb, nest);
301 nla_nest_cancel(skb, nest);
305 static const struct nla_policy bitset_policy[ETHTOOL_A_BITSET_MAX + 1] = {
306 [ETHTOOL_A_BITSET_UNSPEC] = { .type = NLA_REJECT },
307 [ETHTOOL_A_BITSET_NOMASK] = { .type = NLA_FLAG },
308 [ETHTOOL_A_BITSET_SIZE] = { .type = NLA_U32 },
309 [ETHTOOL_A_BITSET_BITS] = { .type = NLA_NESTED },
310 [ETHTOOL_A_BITSET_VALUE] = { .type = NLA_BINARY },
311 [ETHTOOL_A_BITSET_MASK] = { .type = NLA_BINARY },
314 static const struct nla_policy bit_policy[ETHTOOL_A_BITSET_BIT_MAX + 1] = {
315 [ETHTOOL_A_BITSET_BIT_UNSPEC] = { .type = NLA_REJECT },
316 [ETHTOOL_A_BITSET_BIT_INDEX] = { .type = NLA_U32 },
317 [ETHTOOL_A_BITSET_BIT_NAME] = { .type = NLA_NUL_STRING },
318 [ETHTOOL_A_BITSET_BIT_VALUE] = { .type = NLA_FLAG },
322 * ethnl_bitset_is_compact() - check if bitset attribute represents a compact
324 * @bitset: nested attribute representing a bitset
325 * @compact: pointer for return value
327 * Return: 0 on success, negative error code on failure
329 int ethnl_bitset_is_compact(const struct nlattr *bitset, bool *compact)
331 struct nlattr *tb[ETHTOOL_A_BITSET_MAX + 1];
334 ret = nla_parse_nested(tb, ETHTOOL_A_BITSET_MAX, bitset,
335 bitset_policy, NULL);
339 if (tb[ETHTOOL_A_BITSET_BITS]) {
340 if (tb[ETHTOOL_A_BITSET_VALUE] || tb[ETHTOOL_A_BITSET_MASK])
345 if (!tb[ETHTOOL_A_BITSET_SIZE] || !tb[ETHTOOL_A_BITSET_VALUE])
353 * ethnl_name_to_idx() - look up string index for a name
354 * @names: array of ETH_GSTRING_LEN sized strings
355 * @n_names: number of strings in the array
356 * @name: name to look up
358 * Return: index of the string if found, -ENOENT if not found
360 static int ethnl_name_to_idx(ethnl_string_array_t names, unsigned int n_names,
368 for (i = 0; i < n_names; i++) {
369 /* names[i] may not be null terminated */
370 if (!strncmp(names[i], name, ETH_GSTRING_LEN) &&
371 strlen(name) <= ETH_GSTRING_LEN)
378 static int ethnl_parse_bit(unsigned int *index, bool *val, unsigned int nbits,
379 const struct nlattr *bit_attr, bool no_mask,
380 ethnl_string_array_t names,
381 struct netlink_ext_ack *extack)
383 struct nlattr *tb[ETHTOOL_A_BITSET_BIT_MAX + 1];
386 ret = nla_parse_nested(tb, ETHTOOL_A_BITSET_BIT_MAX, bit_attr,
391 if (tb[ETHTOOL_A_BITSET_BIT_INDEX]) {
394 idx = nla_get_u32(tb[ETHTOOL_A_BITSET_BIT_INDEX]);
396 NL_SET_ERR_MSG_ATTR(extack,
397 tb[ETHTOOL_A_BITSET_BIT_INDEX],
398 "bit index too high");
401 name = names ? names[idx] : NULL;
402 if (tb[ETHTOOL_A_BITSET_BIT_NAME] && name &&
403 strncmp(nla_data(tb[ETHTOOL_A_BITSET_BIT_NAME]), name,
404 nla_len(tb[ETHTOOL_A_BITSET_BIT_NAME]))) {
405 NL_SET_ERR_MSG_ATTR(extack, bit_attr,
406 "bit index and name mismatch");
409 } else if (tb[ETHTOOL_A_BITSET_BIT_NAME]) {
410 idx = ethnl_name_to_idx(names, nbits,
411 nla_data(tb[ETHTOOL_A_BITSET_BIT_NAME]));
413 NL_SET_ERR_MSG_ATTR(extack,
414 tb[ETHTOOL_A_BITSET_BIT_NAME],
415 "bit name not found");
419 NL_SET_ERR_MSG_ATTR(extack, bit_attr,
420 "neither bit index nor name specified");
425 *val = no_mask || tb[ETHTOOL_A_BITSET_BIT_VALUE];
430 ethnl_update_bitset32_verbose(u32 *bitmap, unsigned int nbits,
431 const struct nlattr *attr, struct nlattr **tb,
432 ethnl_string_array_t names,
433 struct netlink_ext_ack *extack, bool *mod)
435 struct nlattr *bit_attr;
440 if (tb[ETHTOOL_A_BITSET_VALUE]) {
441 NL_SET_ERR_MSG_ATTR(extack, tb[ETHTOOL_A_BITSET_VALUE],
442 "value only allowed in compact bitset");
445 if (tb[ETHTOOL_A_BITSET_MASK]) {
446 NL_SET_ERR_MSG_ATTR(extack, tb[ETHTOOL_A_BITSET_MASK],
447 "mask only allowed in compact bitset");
450 no_mask = tb[ETHTOOL_A_BITSET_NOMASK];
452 nla_for_each_nested(bit_attr, tb[ETHTOOL_A_BITSET_BITS], rem) {
453 bool old_val, new_val;
456 if (nla_type(bit_attr) != ETHTOOL_A_BITSET_BITS_BIT) {
457 NL_SET_ERR_MSG_ATTR(extack, bit_attr,
458 "only ETHTOOL_A_BITSET_BITS_BIT allowed in ETHTOOL_A_BITSET_BITS");
461 ret = ethnl_parse_bit(&idx, &new_val, nbits, bit_attr, no_mask,
465 old_val = bitmap[idx / 32] & ((u32)1 << (idx % 32));
466 if (new_val != old_val) {
468 bitmap[idx / 32] |= ((u32)1 << (idx % 32));
470 bitmap[idx / 32] &= ~((u32)1 << (idx % 32));
478 static int ethnl_compact_sanity_checks(unsigned int nbits,
479 const struct nlattr *nest,
481 struct netlink_ext_ack *extack)
483 bool no_mask = tb[ETHTOOL_A_BITSET_NOMASK];
484 unsigned int attr_nbits, attr_nwords;
485 const struct nlattr *test_attr;
487 if (no_mask && tb[ETHTOOL_A_BITSET_MASK]) {
488 NL_SET_ERR_MSG_ATTR(extack, tb[ETHTOOL_A_BITSET_MASK],
489 "mask not allowed in list bitset");
492 if (!tb[ETHTOOL_A_BITSET_SIZE]) {
493 NL_SET_ERR_MSG_ATTR(extack, nest,
494 "missing size in compact bitset");
497 if (!tb[ETHTOOL_A_BITSET_VALUE]) {
498 NL_SET_ERR_MSG_ATTR(extack, nest,
499 "missing value in compact bitset");
502 if (!no_mask && !tb[ETHTOOL_A_BITSET_MASK]) {
503 NL_SET_ERR_MSG_ATTR(extack, nest,
504 "missing mask in compact nonlist bitset");
508 attr_nbits = nla_get_u32(tb[ETHTOOL_A_BITSET_SIZE]);
509 attr_nwords = DIV_ROUND_UP(attr_nbits, 32);
510 if (nla_len(tb[ETHTOOL_A_BITSET_VALUE]) != attr_nwords * sizeof(u32)) {
511 NL_SET_ERR_MSG_ATTR(extack, tb[ETHTOOL_A_BITSET_VALUE],
512 "bitset value length does not match size");
515 if (tb[ETHTOOL_A_BITSET_MASK] &&
516 nla_len(tb[ETHTOOL_A_BITSET_MASK]) != attr_nwords * sizeof(u32)) {
517 NL_SET_ERR_MSG_ATTR(extack, tb[ETHTOOL_A_BITSET_MASK],
518 "bitset mask length does not match size");
521 if (attr_nbits <= nbits)
524 test_attr = no_mask ? tb[ETHTOOL_A_BITSET_VALUE] :
525 tb[ETHTOOL_A_BITSET_MASK];
526 if (ethnl_bitmap32_not_zero(nla_data(test_attr), nbits, attr_nbits)) {
527 NL_SET_ERR_MSG_ATTR(extack, test_attr,
528 "cannot modify bits past kernel bitset size");
535 * ethnl_update_bitset32() - Apply a bitset nest to a u32 based bitmap
536 * @bitmap: bitmap to update
537 * @nbits: size of the updated bitmap in bits
538 * @attr: nest attribute to parse and apply
539 * @names: array of bit names; may be null for compact format
540 * @extack: extack for error reporting
541 * @mod: set this to true if bitmap is modified, leave as it is if not
543 * Apply bitset netsted attribute to a bitmap. If the attribute represents
544 * a bit list, @bitmap is set to its contents; otherwise, bits in mask are
545 * set to values from value. Bitmaps in the attribute may be longer than
546 * @nbits but the message must not request modifying any bits past @nbits.
548 * Return: negative error code on failure, 0 on success
550 int ethnl_update_bitset32(u32 *bitmap, unsigned int nbits,
551 const struct nlattr *attr, ethnl_string_array_t names,
552 struct netlink_ext_ack *extack, bool *mod)
554 struct nlattr *tb[ETHTOOL_A_BITSET_MAX + 1];
555 unsigned int change_bits;
561 ret = nla_parse_nested(tb, ETHTOOL_A_BITSET_MAX, attr, bitset_policy,
566 if (tb[ETHTOOL_A_BITSET_BITS])
567 return ethnl_update_bitset32_verbose(bitmap, nbits, attr, tb,
569 ret = ethnl_compact_sanity_checks(nbits, attr, tb, extack);
573 no_mask = tb[ETHTOOL_A_BITSET_NOMASK];
574 change_bits = min_t(unsigned int,
575 nla_get_u32(tb[ETHTOOL_A_BITSET_SIZE]), nbits);
576 ethnl_bitmap32_update(bitmap, change_bits,
577 nla_data(tb[ETHTOOL_A_BITSET_VALUE]),
579 nla_data(tb[ETHTOOL_A_BITSET_MASK]),
581 if (no_mask && change_bits < nbits)
582 ethnl_bitmap32_clear(bitmap, change_bits, nbits, mod);
587 #if BITS_PER_LONG == 64 && defined(__BIG_ENDIAN)
589 /* 64-bit big endian architectures are the only case when u32 based bitmaps
590 * and unsigned long based bitmaps have different memory layout so that we
591 * cannot simply cast the latter to the former and need actual wrappers
592 * converting the latter to the former.
594 * To reduce the number of slab allocations, the wrappers use fixed size local
595 * variables for bitmaps up to ETHNL_SMALL_BITMAP_BITS bits which is the
596 * majority of bitmaps used by ethtool.
598 #define ETHNL_SMALL_BITMAP_BITS 128
599 #define ETHNL_SMALL_BITMAP_WORDS DIV_ROUND_UP(ETHNL_SMALL_BITMAP_BITS, 32)
601 int ethnl_bitset_size(const unsigned long *val, const unsigned long *mask,
602 unsigned int nbits, ethnl_string_array_t names,
605 u32 small_mask32[ETHNL_SMALL_BITMAP_WORDS];
606 u32 small_val32[ETHNL_SMALL_BITMAP_WORDS];
611 if (nbits > ETHNL_SMALL_BITMAP_BITS) {
612 unsigned int nwords = DIV_ROUND_UP(nbits, 32);
614 val32 = kmalloc_array(2 * nwords, sizeof(u32), GFP_KERNEL);
617 mask32 = val32 + nwords;
620 mask32 = small_mask32;
623 bitmap_to_arr32(val32, val, nbits);
625 bitmap_to_arr32(mask32, mask, nbits);
628 ret = ethnl_bitset32_size(val32, mask32, nbits, names, compact);
630 if (nbits > ETHNL_SMALL_BITMAP_BITS)
636 int ethnl_put_bitset(struct sk_buff *skb, int attrtype,
637 const unsigned long *val, const unsigned long *mask,
638 unsigned int nbits, ethnl_string_array_t names,
641 u32 small_mask32[ETHNL_SMALL_BITMAP_WORDS];
642 u32 small_val32[ETHNL_SMALL_BITMAP_WORDS];
647 if (nbits > ETHNL_SMALL_BITMAP_BITS) {
648 unsigned int nwords = DIV_ROUND_UP(nbits, 32);
650 val32 = kmalloc_array(2 * nwords, sizeof(u32), GFP_KERNEL);
653 mask32 = val32 + nwords;
656 mask32 = small_mask32;
659 bitmap_to_arr32(val32, val, nbits);
661 bitmap_to_arr32(mask32, mask, nbits);
664 ret = ethnl_put_bitset32(skb, attrtype, val32, mask32, nbits, names,
667 if (nbits > ETHNL_SMALL_BITMAP_BITS)
673 int ethnl_update_bitset(unsigned long *bitmap, unsigned int nbits,
674 const struct nlattr *attr, ethnl_string_array_t names,
675 struct netlink_ext_ack *extack, bool *mod)
677 u32 small_bitmap32[ETHNL_SMALL_BITMAP_WORDS];
678 u32 *bitmap32 = small_bitmap32;
679 bool u32_mod = false;
682 if (nbits > ETHNL_SMALL_BITMAP_BITS) {
683 unsigned int dst_words = DIV_ROUND_UP(nbits, 32);
685 bitmap32 = kmalloc_array(dst_words, sizeof(u32), GFP_KERNEL);
690 bitmap_to_arr32(bitmap32, bitmap, nbits);
691 ret = ethnl_update_bitset32(bitmap32, nbits, attr, names, extack,
694 bitmap_from_arr32(bitmap, bitmap32, nbits);
698 if (nbits > ETHNL_SMALL_BITMAP_BITS)
706 /* On little endian 64-bit and all 32-bit architectures, an unsigned long
707 * based bitmap can be interpreted as u32 based one using a simple cast.
710 int ethnl_bitset_size(const unsigned long *val, const unsigned long *mask,
711 unsigned int nbits, ethnl_string_array_t names,
714 return ethnl_bitset32_size((const u32 *)val, (const u32 *)mask, nbits,
718 int ethnl_put_bitset(struct sk_buff *skb, int attrtype,
719 const unsigned long *val, const unsigned long *mask,
720 unsigned int nbits, ethnl_string_array_t names,
723 return ethnl_put_bitset32(skb, attrtype, (const u32 *)val,
724 (const u32 *)mask, nbits, names, compact);
727 int ethnl_update_bitset(unsigned long *bitmap, unsigned int nbits,
728 const struct nlattr *attr, ethnl_string_array_t names,
729 struct netlink_ext_ack *extack, bool *mod)
731 return ethnl_update_bitset32((u32 *)bitmap, nbits, attr, names, extack,
735 #endif /* BITS_PER_LONG == 64 && defined(__BIG_ENDIAN) */