76 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			76 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * From lib/bitmap.c
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|  * Helper functions for bitmap.h.
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|  *
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|  * This source code is licensed under the GNU General Public License,
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|  * Version 2.  See the file COPYING for more details.
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|  */
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| #include <linux/bitmap.h>
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| 
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| int __bitmap_weight(const unsigned long *bitmap, int bits)
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| {
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| 	int k, w = 0, lim = bits/BITS_PER_LONG;
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| 
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| 	for (k = 0; k < lim; k++)
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| 		w += hweight_long(bitmap[k]);
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| 
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| 	if (bits % BITS_PER_LONG)
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| 		w += hweight_long(bitmap[k] & BITMAP_LAST_WORD_MASK(bits));
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| 
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| 	return w;
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| }
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| 
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| void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
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| 		 const unsigned long *bitmap2, int bits)
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| {
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| 	int k;
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| 	int nr = BITS_TO_LONGS(bits);
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| 
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| 	for (k = 0; k < nr; k++)
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| 		dst[k] = bitmap1[k] | bitmap2[k];
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| }
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| 
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| size_t bitmap_scnprintf(unsigned long *bitmap, int nbits,
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| 			char *buf, size_t size)
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| {
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| 	/* current bit is 'cur', most recently seen range is [rbot, rtop] */
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| 	int cur, rbot, rtop;
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| 	bool first = true;
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| 	size_t ret = 0;
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| 
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| 	rbot = cur = find_first_bit(bitmap, nbits);
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| 	while (cur < nbits) {
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| 		rtop = cur;
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| 		cur = find_next_bit(bitmap, nbits, cur + 1);
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| 		if (cur < nbits && cur <= rtop + 1)
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| 			continue;
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| 
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| 		if (!first)
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| 			ret += scnprintf(buf + ret, size - ret, ",");
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| 
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| 		first = false;
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| 
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| 		ret += scnprintf(buf + ret, size - ret, "%d", rbot);
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| 		if (rbot < rtop)
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| 			ret += scnprintf(buf + ret, size - ret, "-%d", rtop);
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| 
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| 		rbot = cur;
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| 	}
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| 	return ret;
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| }
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| 
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| int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
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| 		 const unsigned long *bitmap2, unsigned int bits)
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| {
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| 	unsigned int k;
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| 	unsigned int lim = bits/BITS_PER_LONG;
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| 	unsigned long result = 0;
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| 
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| 	for (k = 0; k < lim; k++)
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| 		result |= (dst[k] = bitmap1[k] & bitmap2[k]);
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| 	if (bits % BITS_PER_LONG)
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| 		result |= (dst[k] = bitmap1[k] & bitmap2[k] &
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| 			   BITMAP_LAST_WORD_MASK(bits));
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| 	return result != 0;
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| }
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