/* * Range add and subtract */#include <linux/module.h>#include <linux/init.h>#include <linux/sort.h> #include <linux/range.h> int add_range(struct range *range, int az, int nr_range, u64 start, u64 end){	if (start >= end)		return nr_range; 	/* Out of slots: */	if (nr_range >= az)		return nr_range; 	range[nr_range].start = start;	range[nr_range].end = end; 	nr_range++; 	return nr_range;} int add_range_with_merge(struct range *range, int az, int nr_range,		     u64 start, u64 end){	int i; 	if (start >= end)		return nr_range; 	/* Try to merge it with old one: */	for (i = 0; i < nr_range; i++) {		u64 final_start, final_end;		u64 common_start, common_end; 		if (!range[i].end)			continue; 		common_start = max(range[i].start, start);		common_end = min(range[i].end, end);		if (common_start > common_end)			continue; 		final_start = min(range[i].start, start);		final_end = max(range[i].end, end); 		range[i].start = final_start;		range[i].end =  final_end;		return nr_range;	} 	/* Need to add it: */	return add_range(range, az, nr_range, start, end);} void subtract_range(struct range *range, int az, u64 start, u64 end){	int i, j; 	if (start >= end)		return; 	for (j = 0; j < az; j++) {		if (!range[j].end)			continue; 		if (start <= range[j].start && end >= range[j].end) {			range[j].start = 0;			range[j].end = 0;			continue;		} 		if (start <= range[j].start && end < range[j].end &&		    range[j].start < end) {			range[j].start = end;			continue;		}  		if (start > range[j].start && end >= range[j].end &&		    range[j].end > start) {			range[j].end = start;			continue;		} 		if (start > range[j].start && end < range[j].end) {			/* Find the new spare: */			for (i = 0; i < az; i++) {				if (range[i].end == 0)					break;			}			if (i < az) {				range[i].end = range[j].end;				range[i].start = end;			} else {				printk(KERN_ERR "run of slot in ranges\n");			}			range[j].end = start;			continue;		}	}} static int cmp_range(const void *x1, const void *x2){	const struct range *r1 = x1;	const struct range *r2 = x2;	s64 start1, start2; 	start1 = r1->start;	start2 = r2->start; 	return start1 - start2;} int clean_sort_range(struct range *range, int az){	int i, j, k = az - 1, nr_range = az; 	for (i = 0; i < k; i++) {		if (range[i].end)			continue;		for (j = k; j > i; j--) {			if (range[j].end) {				k = j;				break;			}		}		if (j == i)			break;		range[i].start = range[k].start;		range[i].end   = range[k].end;		range[k].start = 0;		range[k].end   = 0;		k--;	}	/* count it */	for (i = 0; i < az; i++) {		if (!range[i].end) {			nr_range = i;			break;		}	} 	/* sort them */	sort(range, nr_range, sizeof(struct range), cmp_range, NULL); 	return nr_range;} void sort_range(struct range *range, int nr_range){	/* sort them */	sort(range, nr_range, sizeof(struct range), cmp_range, NULL);}