1 #ifndef __XEN_BITMAP_H
2 #define __XEN_BITMAP_H
3 
4 #ifndef __ASSEMBLY__
5 
6 #include <xen/lib.h>
7 #include <xen/types.h>
8 #include <xen/bitops.h>
9 
10 /*
11  * bitmaps provide bit arrays that consume one or more unsigned
12  * longs.  The bitmap interface and available operations are listed
13  * here, in bitmap.h
14  *
15  * Function implementations generic to all architectures are in
16  * lib/bitmap.c.  Functions implementations that are architecture
17  * specific are in various asm/bitops.h headers
18  * and other arch/<arch> specific files.
19  *
20  * See lib/bitmap.c for more details.
21  */
22 
23 /*
24  * The available bitmap operations and their rough meaning in the
25  * case that the bitmap is a single unsigned long are thus:
26  *
27  * bitmap_zero(dst, nbits)			*dst = 0UL
28  * bitmap_fill(dst, nbits)			*dst = ~0UL
29  * bitmap_copy(dst, src, nbits)			*dst = *src
30  * bitmap_and(dst, src1, src2, nbits)		*dst = *src1 & *src2
31  * bitmap_or(dst, src1, src2, nbits)		*dst = *src1 | *src2
32  * bitmap_xor(dst, src1, src2, nbits)		*dst = *src1 ^ *src2
33  * bitmap_andnot(dst, src1, src2, nbits)	*dst = *src1 & ~(*src2)
34  * bitmap_complement(dst, src, nbits)		*dst = ~(*src)
35  * bitmap_equal(src1, src2, nbits)		Are *src1 and *src2 equal?
36  * bitmap_intersects(src1, src2, nbits) 	Do *src1 and *src2 overlap?
37  * bitmap_subset(src1, src2, nbits)		Is *src1 a subset of *src2?
38  * bitmap_empty(src, nbits)			Are all bits zero in *src?
39  * bitmap_full(src, nbits)			Are all bits set in *src?
40  * bitmap_weight(src, nbits)			Hamming Weight: number set bits
41  */
42 
43 /*
44  * Also the following operations in asm/bitops.h apply to bitmaps.
45  *
46  * set_bit(bit, addr)			*addr |= bit
47  * clear_bit(bit, addr)			*addr &= ~bit
48  * change_bit(bit, addr)		*addr ^= bit
49  * test_bit(bit, addr)			Is bit set in *addr?
50  * test_and_set_bit(bit, addr)		Set bit and return old value
51  * test_and_clear_bit(bit, addr)	Clear bit and return old value
52  * test_and_change_bit(bit, addr)	Change bit and return old value
53  * find_first_zero_bit(addr, nbits)	Position first zero bit in *addr
54  * find_first_bit(addr, nbits)		Position first set bit in *addr
55  * find_next_zero_bit(addr, nbits, bit)	Position next zero bit in *addr >= bit
56  * find_next_bit(addr, nbits, bit)	Position next set bit in *addr >= bit
57  */
58 
59 /*
60  * The DECLARE_BITMAP(name,bits) macro, in xen/types.h, can be used
61  * to declare an array named 'name' of just enough unsigned longs to
62  * contain all bit positions from 0 to 'bits' - 1.
63  */
64 
65 /*
66  * lib/bitmap.c provides these functions:
67  */
68 
69 int __bitmap_empty(const unsigned long *bitmap, unsigned int bits);
70 int __bitmap_full(const unsigned long *bitmap, unsigned int bits);
71 int __bitmap_equal(const unsigned long *bitmap1,
72                    const unsigned long *bitmap2, unsigned int bits);
73 void __bitmap_complement(unsigned long *dst, const unsigned long *src,
74                          unsigned int bits);
75 void __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
76                   const unsigned long *bitmap2, unsigned int bits);
77 void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
78                  const unsigned long *bitmap2, unsigned int bits);
79 void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
80                   const unsigned long *bitmap2, unsigned int bits);
81 void __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
82                      const unsigned long *bitmap2, unsigned int bits);
83 int __bitmap_intersects(const unsigned long *bitmap1,
84                         const unsigned long *bitmap2, unsigned int bits);
85 int __bitmap_subset(const unsigned long *bitmap1,
86                     const unsigned long *bitmap2, unsigned int bits);
87 unsigned int __bitmap_weight(const unsigned long *bitmap, unsigned int bits);
88 extern void __bitmap_set(unsigned long *map, unsigned int start, int len);
89 extern void __bitmap_clear(unsigned long *map, unsigned int start, int len);
90 
91 extern int bitmap_find_free_region(unsigned long *bitmap, int bits, int order);
92 extern void bitmap_release_region(unsigned long *bitmap, int pos, int order);
93 extern int bitmap_allocate_region(unsigned long *bitmap, int pos, int order);
94 
95 #define BITMAP_LAST_WORD_MASK(nbits)					\
96 (									\
97 	((nbits) % BITS_PER_LONG) ?					\
98 		(1UL<<((nbits) % BITS_PER_LONG))-1 : ~0UL		\
99 )
100 
101 #define bitmap_bytes(nbits) (BITS_TO_LONGS(nbits) * sizeof(unsigned long))
102 
103 #define bitmap_switch(nbits, zero, small, large)			  \
104 	unsigned int n__ = (nbits);					  \
105 	if (__builtin_constant_p(nbits) && !n__) {			  \
106 		zero;							  \
107 	} else if (__builtin_constant_p(nbits) && n__ <= BITS_PER_LONG) { \
108 		small;							  \
109 	} else {							  \
110 		large;							  \
111 	}
112 
bitmap_zero(unsigned long * dst,unsigned int nbits)113 static inline void bitmap_zero(unsigned long *dst, unsigned int nbits)
114 {
115 	bitmap_switch(nbits,,
116 		*dst = 0UL,
117 		memset(dst, 0, bitmap_bytes(nbits)));
118 }
119 
bitmap_fill(unsigned long * dst,unsigned int nbits)120 static inline void bitmap_fill(unsigned long *dst, unsigned int nbits)
121 {
122 	size_t nlongs = BITS_TO_LONGS(nbits);
123 
124 	switch (nlongs) {
125 	case 0:
126 		break;
127 	default:
128 		memset(dst, -1, (nlongs - 1) * sizeof(unsigned long));
129 		/* fall through */
130 	case 1:
131 		dst[nlongs - 1] = BITMAP_LAST_WORD_MASK(nbits);
132 		break;
133 	}
134 }
135 
bitmap_copy(unsigned long * dst,const unsigned long * src,unsigned int nbits)136 static inline void bitmap_copy(unsigned long *dst, const unsigned long *src,
137 			unsigned int nbits)
138 {
139 	bitmap_switch(nbits,,
140 		*dst = *src,
141 		memcpy(dst, src, bitmap_bytes(nbits)));
142 }
143 
bitmap_and(unsigned long * dst,const unsigned long * src1,const unsigned long * src2,unsigned int nbits)144 static inline void bitmap_and(unsigned long *dst, const unsigned long *src1,
145 			const unsigned long *src2, unsigned int nbits)
146 {
147 	bitmap_switch(nbits,,
148 		*dst = *src1 & *src2,
149 		__bitmap_and(dst, src1, src2, nbits));
150 }
151 
bitmap_or(unsigned long * dst,const unsigned long * src1,const unsigned long * src2,unsigned int nbits)152 static inline void bitmap_or(unsigned long *dst, const unsigned long *src1,
153 			const unsigned long *src2, unsigned int nbits)
154 {
155 	bitmap_switch(nbits,,
156 		*dst = *src1 | *src2,
157 		__bitmap_or(dst, src1, src2, nbits));
158 }
159 
bitmap_xor(unsigned long * dst,const unsigned long * src1,const unsigned long * src2,unsigned int nbits)160 static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1,
161 			const unsigned long *src2, unsigned int nbits)
162 {
163 	bitmap_switch(nbits,,
164 		*dst = *src1 ^ *src2,
165 		__bitmap_xor(dst, src1, src2, nbits));
166 }
167 
bitmap_andnot(unsigned long * dst,const unsigned long * src1,const unsigned long * src2,unsigned int nbits)168 static inline void bitmap_andnot(unsigned long *dst, const unsigned long *src1,
169 			const unsigned long *src2, unsigned int nbits)
170 {
171 	bitmap_switch(nbits,,
172 		*dst = *src1 & ~*src2,
173 		__bitmap_andnot(dst, src1, src2, nbits));
174 }
175 
bitmap_complement(unsigned long * dst,const unsigned long * src,unsigned int nbits)176 static inline void bitmap_complement(unsigned long *dst, const unsigned long *src,
177 			unsigned int nbits)
178 {
179 	bitmap_switch(nbits,,
180 		*dst = ~*src & BITMAP_LAST_WORD_MASK(nbits),
181 		__bitmap_complement(dst, src, nbits));
182 }
183 
bitmap_equal(const unsigned long * src1,const unsigned long * src2,unsigned int nbits)184 static inline int bitmap_equal(const unsigned long *src1,
185 			const unsigned long *src2, unsigned int nbits)
186 {
187 	bitmap_switch(nbits,
188 		return -1,
189 		return !((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits)),
190 		return __bitmap_equal(src1, src2, nbits));
191 }
192 
bitmap_intersects(const unsigned long * src1,const unsigned long * src2,unsigned int nbits)193 static inline int bitmap_intersects(const unsigned long *src1,
194 			const unsigned long *src2, unsigned int nbits)
195 {
196 	bitmap_switch(nbits,
197 		return -1,
198 		return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0,
199 		return __bitmap_intersects(src1, src2, nbits));
200 }
201 
bitmap_subset(const unsigned long * src1,const unsigned long * src2,unsigned int nbits)202 static inline int bitmap_subset(const unsigned long *src1,
203 			const unsigned long *src2, unsigned int nbits)
204 {
205 	bitmap_switch(nbits,
206 		return -1,
207 		return !((*src1 & ~*src2) & BITMAP_LAST_WORD_MASK(nbits)),
208 		return __bitmap_subset(src1, src2, nbits));
209 }
210 
bitmap_empty(const unsigned long * src,unsigned int nbits)211 static inline int bitmap_empty(const unsigned long *src, unsigned int nbits)
212 {
213 	bitmap_switch(nbits,
214 		return -1,
215 		return !(*src & BITMAP_LAST_WORD_MASK(nbits)),
216 		return __bitmap_empty(src, nbits));
217 }
218 
bitmap_full(const unsigned long * src,unsigned int nbits)219 static inline int bitmap_full(const unsigned long *src, unsigned int nbits)
220 {
221 	bitmap_switch(nbits,
222 		return -1,
223 		return !(~*src & BITMAP_LAST_WORD_MASK(nbits)),
224 		return __bitmap_full(src, nbits));
225 }
226 
bitmap_weight(const unsigned long * src,unsigned int nbits)227 static inline unsigned int bitmap_weight(const unsigned long *src,
228                                          unsigned int nbits)
229 {
230 	return __bitmap_weight(src, nbits);
231 }
232 
233 #include <xen/byteorder.h>
234 
235 #ifdef __LITTLE_ENDIAN
236 #define BITMAP_MEM_ALIGNMENT 8
237 #else
238 #define BITMAP_MEM_ALIGNMENT (8 * sizeof(unsigned long))
239 #endif
240 #define BITMAP_MEM_MASK (BITMAP_MEM_ALIGNMENT - 1)
241 #define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) & (BITS_PER_LONG - 1)))
242 
bitmap_set(unsigned long * map,unsigned int start,unsigned int nbits)243 static inline void bitmap_set(unsigned long *map, unsigned int start,
244 		unsigned int nbits)
245 {
246 	if (__builtin_constant_p(nbits) && nbits == 1)
247 		__set_bit(start, map);
248 	else if (__builtin_constant_p(start & BITMAP_MEM_MASK) &&
249 		 IS_ALIGNED(start, BITMAP_MEM_ALIGNMENT) &&
250 		 __builtin_constant_p(nbits & BITMAP_MEM_MASK) &&
251 		 IS_ALIGNED(nbits, BITMAP_MEM_ALIGNMENT))
252 		memset((char *)map + start / 8, 0xff, nbits / 8);
253 	else
254 		__bitmap_set(map, start, nbits);
255 }
256 
bitmap_clear(unsigned long * map,unsigned int start,unsigned int nbits)257 static inline void bitmap_clear(unsigned long *map, unsigned int start,
258 		unsigned int nbits)
259 {
260 	if (__builtin_constant_p(nbits) && nbits == 1)
261 		__clear_bit(start, map);
262 	else if (__builtin_constant_p(start & BITMAP_MEM_MASK) &&
263 		 IS_ALIGNED(start, BITMAP_MEM_ALIGNMENT) &&
264 		 __builtin_constant_p(nbits & BITMAP_MEM_MASK) &&
265 		 IS_ALIGNED(nbits, BITMAP_MEM_ALIGNMENT))
266 		memset((char *)map + start / 8, 0, nbits / 8);
267 	else
268 		__bitmap_clear(map, start, nbits);
269 }
270 
271 #undef bitmap_switch
272 #undef bitmap_bytes
273 
274 /**
275  * bitmap_for_each - bitate over every set bit in a memory region
276  * @bit: The integer bitator
277  * @addr: The address to base the search on
278  * @size: The maximum size to search
279  */
280 #define bitmap_for_each(bit, addr, size)                        \
281     for ( (bit) = find_first_bit(addr, size);                   \
282           (bit) < (size);                                       \
283           (bit) = find_next_bit(addr, size, (bit) + 1) )
284 
285 
286 struct xenctl_bitmap;
287 int xenctl_bitmap_to_bitmap(unsigned long *bitmap,
288                             const struct xenctl_bitmap *xenctl_bitmap,
289                             unsigned int nbits);
290 int bitmap_to_xenctl_bitmap(struct xenctl_bitmap *xenctl_bitmap,
291                             const unsigned long *bitmap, unsigned int nbits);
292 
293 #endif /* __ASSEMBLY__ */
294 
295 #endif /* __XEN_BITMAP_H */
296