2 * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014 Nicira, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
24 static inline unsigned long *
25 bitmap_unit__(const unsigned long *bitmap, size_t offset)
27 return CONST_CAST(unsigned long *, &bitmap[offset / BITMAP_ULONG_BITS]);
30 static inline unsigned long
31 bitmap_bit__(size_t offset)
33 return 1UL << (offset % BITMAP_ULONG_BITS);
37 bitmap_n_longs(size_t n_bits)
39 return BITMAP_N_LONGS(n_bits);
43 bitmap_n_bytes(size_t n_bits)
45 return bitmap_n_longs(n_bits) * sizeof(unsigned long int);
48 static inline unsigned long *
49 bitmap_allocate(size_t n_bits)
51 return xzalloc(bitmap_n_bytes(n_bits));
54 /* Initializes bitmap to all-1-bits and returns the bitmap pointer. */
55 static inline unsigned long *
56 bitmap_init1(unsigned long *bitmap, size_t n_bits)
58 size_t n_longs = bitmap_n_longs(n_bits);
59 size_t n_bytes = bitmap_n_bytes(n_bits);
60 size_t r_bits = n_bits % BITMAP_ULONG_BITS;
62 memset(bitmap, 0xff, n_bytes);
64 bitmap[n_longs - 1] >>= BITMAP_ULONG_BITS - r_bits;
69 /* Allocates and returns a bitmap initialized to all-1-bits. */
70 static inline unsigned long *
71 bitmap_allocate1(size_t n_bits)
73 return bitmap_init1(xmalloc(bitmap_n_bytes(n_bits)), n_bits);
76 static inline unsigned long *
77 bitmap_clone(const unsigned long *bitmap, size_t n_bits)
79 return xmemdup(bitmap, bitmap_n_bytes(n_bits));
83 bitmap_free(unsigned long *bitmap)
89 bitmap_is_set(const unsigned long *bitmap, size_t offset)
91 return (*bitmap_unit__(bitmap, offset) & bitmap_bit__(offset)) != 0;
94 static inline unsigned long *
95 bitmap_set1(unsigned long *bitmap, size_t offset)
97 *bitmap_unit__(bitmap, offset) |= bitmap_bit__(offset);
101 static inline unsigned long *
102 bitmap_set0(unsigned long *bitmap, size_t offset)
104 *bitmap_unit__(bitmap, offset) &= ~bitmap_bit__(offset);
108 static inline unsigned long *
109 bitmap_set(unsigned long *bitmap, size_t offset, bool value)
111 return (value) ? bitmap_set1(bitmap, offset) : bitmap_set0(bitmap, offset);
114 /* Sets 'n' bits of a single unit. */
116 bitmap_set_n__(unsigned long *bitmap, size_t start, size_t n, bool value)
118 unsigned long mask = ((1UL << n) - 1) << start % BITMAP_ULONG_BITS;
121 *bitmap_unit__(bitmap, start) |= mask;
123 *bitmap_unit__(bitmap, start) &= ~mask;
127 /* Sets 'count' consecutive bits in 'bitmap', starting at bit offset 'start',
129 static inline unsigned long *
130 bitmap_set_multiple(unsigned long *bitmap, size_t start, size_t count,
133 if (count && start % BITMAP_ULONG_BITS) {
134 size_t n = MIN(count, BITMAP_ULONG_BITS - start % BITMAP_ULONG_BITS);
136 bitmap_set_n__(bitmap, start, n, value);
140 for (; count >= BITMAP_ULONG_BITS; count -= BITMAP_ULONG_BITS) {
141 *bitmap_unit__(bitmap, start) = (unsigned long)!value - 1;
142 start += BITMAP_ULONG_BITS;
145 bitmap_set_n__(bitmap, start, count, value);
150 /* Returns the number of 1-bits in the 'n'-bit bitmap at 'bitmap'. */
152 bitmap_count1(const unsigned long int *bitmap, size_t n)
157 BUILD_ASSERT(ULONG_MAX <= UINT64_MAX);
158 for (i = 0; i < BITMAP_N_LONGS(n); i++) {
159 count += count_1bits(bitmap[i]);
164 /* "dst &= arg;" for n-bit dst and arg. */
165 static inline unsigned long *
166 bitmap_and(unsigned long *dst, const unsigned long *arg, size_t n)
170 for (i = 0; i < BITMAP_N_LONGS(n); i++) {
176 /* "dst |= arg;" for n-bit dst and arg. */
177 static inline unsigned long *
178 bitmap_or(unsigned long *dst, const unsigned long *arg, size_t n)
182 for (i = 0; i < BITMAP_N_LONGS(n); i++) {
188 /* "dst = ~dst;" for n-bit dst. */
189 static inline unsigned long *
190 bitmap_not(unsigned long *dst, size_t n)
194 for (i = 0; i < n / BITMAP_ULONG_BITS; i++) {
197 if (n % BITMAP_ULONG_BITS) {
198 dst[i] ^= (1UL << (n % BITMAP_ULONG_BITS)) - 1;
203 /* Compares the 'n' bits in bitmaps 'a' and 'b'. Returns true if all bits are
204 * equal, false otherwise. */
206 bitmap_equal(const unsigned long *a, const unsigned long *b, size_t n)
208 if (memcmp(a, b, n / BITMAP_ULONG_BITS * sizeof(unsigned long))) {
211 if (n % BITMAP_ULONG_BITS) {
212 unsigned long mask = (1UL << n % BITMAP_ULONG_BITS) - 1;
213 unsigned long diff = *bitmap_unit__(a, n) ^ *bitmap_unit__(b, n);
215 return !(diff & mask);
220 /* Scans 'bitmap' from bit offset 'start' to 'end', excluding 'end' itself.
221 * Returns the bit offset of the lowest-numbered bit set to 'target', or 'end'
222 * if all of the bits are set to '!target'. 'target' is typically a
223 * compile-time constant, so it makes sense to inline this. Compiler may also
224 * optimize parts away depending on the 'start' and 'end' values passed in. */
226 bitmap_scan(const unsigned long *bitmap, bool target, size_t start, size_t end)
228 if (OVS_LIKELY(start < end)) {
229 unsigned long *p, unit;
231 p = bitmap_unit__(bitmap, start);
232 unit = (target ? *p : ~*p) >> (start % BITMAP_ULONG_BITS);
234 start -= start % BITMAP_ULONG_BITS; /* Round down. */
235 start += BITMAP_ULONG_BITS; /* Start of the next unit. */
237 for (; start < end; start += BITMAP_ULONG_BITS) {
238 unit = target ? *++p : ~*++p;
246 start += raw_ctz(unit); /* unit != 0 */
247 if (OVS_LIKELY(start < end)) {
254 /* Returns true if all of the 'n' bits in 'bitmap' are 0,
255 * false if at least one bit is a 1.*/
257 bitmap_is_all_zeros(const unsigned long *bitmap, size_t n)
259 return bitmap_scan(bitmap, true, 0, n) == n;
262 #define BITMAP_FOR_EACH_1_RANGE(IDX, BEGIN, END, BITMAP) \
263 for ((IDX) = bitmap_scan(BITMAP, true, BEGIN, END); (IDX) < (END); \
264 (IDX) = bitmap_scan(BITMAP, true, (IDX) + 1, END))
265 #define BITMAP_FOR_EACH_1(IDX, SIZE, BITMAP) \
266 BITMAP_FOR_EACH_1_RANGE(IDX, 0, SIZE, BITMAP)
268 /* More efficient access to a map of single ullong. */
269 #define ULLONG_FOR_EACH_1(IDX, MAP) \
270 for (uint64_t map__ = (MAP); \
271 map__ && (((IDX) = raw_ctz(map__)), true); \
272 map__ = zero_rightmost_1bit(map__))
274 #define ULLONG_SET0(MAP, OFFSET) ((MAP) &= ~(1ULL << (OFFSET)))
275 #define ULLONG_SET1(MAP, OFFSET) ((MAP) |= 1ULL << (OFFSET))
277 /* Returns the value of a bit in a map as a bool. */
278 #define ULLONG_GET(MAP, OFFSET) !!((MAP) & (1ULL << (OFFSET)))
280 #endif /* bitmap.h */