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  1/*
  2 * Range add and subtract
  3 */
  4#include <linux/kernel.h>
  5#include <linux/init.h>
  6#include <linux/sort.h>
  7#include <linux/string.h>
  8#include <linux/range.h>
  9
 10int add_range(struct range *range, int az, int nr_range, u64 start, u64 end)
 11{
 12	if (start >= end)
 13		return nr_range;
 14
 15	/* Out of slots: */
 16	if (nr_range >= az)
 17		return nr_range;
 18
 19	range[nr_range].start = start;
 20	range[nr_range].end = end;
 21
 22	nr_range++;
 23
 24	return nr_range;
 25}
 26
 27int add_range_with_merge(struct range *range, int az, int nr_range,
 28		     u64 start, u64 end)
 29{
 30	int i;
 31
 32	if (start >= end)
 33		return nr_range;
 34
 35	/* get new start/end: */
 36	for (i = 0; i < nr_range; i++) {
 37		u64 common_start, common_end;
 38
 39		if (!range[i].end)
 40			continue;
 41
 42		common_start = max(range[i].start, start);
 43		common_end = min(range[i].end, end);
 44		if (common_start > common_end)
 45			continue;
 46
 47		/* new start/end, will add it back at last */
 48		start = min(range[i].start, start);
 49		end = max(range[i].end, end);
 50
 51		memmove(&range[i], &range[i + 1],
 52			(nr_range - (i + 1)) * sizeof(range[i]));
 53		range[nr_range - 1].start = 0;
 54		range[nr_range - 1].end   = 0;
 55		nr_range--;
 56		i--;
 57	}
 58
 59	/* Need to add it: */
 60	return add_range(range, az, nr_range, start, end);
 61}
 62
 63void subtract_range(struct range *range, int az, u64 start, u64 end)
 64{
 65	int i, j;
 66
 67	if (start >= end)
 68		return;
 69
 70	for (j = 0; j < az; j++) {
 71		if (!range[j].end)
 72			continue;
 73
 74		if (start <= range[j].start && end >= range[j].end) {
 75			range[j].start = 0;
 76			range[j].end = 0;
 77			continue;
 78		}
 79
 80		if (start <= range[j].start && end < range[j].end &&
 81		    range[j].start < end) {
 82			range[j].start = end;
 83			continue;
 84		}
 85
 86
 87		if (start > range[j].start && end >= range[j].end &&
 88		    range[j].end > start) {
 89			range[j].end = start;
 90			continue;
 91		}
 92
 93		if (start > range[j].start && end < range[j].end) {
 94			/* Find the new spare: */
 95			for (i = 0; i < az; i++) {
 96				if (range[i].end == 0)
 97					break;
 98			}
 99			if (i < az) {
100				range[i].end = range[j].end;
101				range[i].start = end;
102			} else {
103				pr_err("%s: run out of slot in ranges\n",
104					__func__);
105			}
106			range[j].end = start;
107			continue;
108		}
109	}
110}
111
112static int cmp_range(const void *x1, const void *x2)
113{
114	const struct range *r1 = x1;
115	const struct range *r2 = x2;
116	s64 start1, start2;
117
118	start1 = r1->start;
119	start2 = r2->start;
120
121	return start1 - start2;
122}
123
124int clean_sort_range(struct range *range, int az)
125{
126	int i, j, k = az - 1, nr_range = az;
127
128	for (i = 0; i < k; i++) {
129		if (range[i].end)
130			continue;
131		for (j = k; j > i; j--) {
132			if (range[j].end) {
133				k = j;
134				break;
135			}
136		}
137		if (j == i)
138			break;
139		range[i].start = range[k].start;
140		range[i].end   = range[k].end;
141		range[k].start = 0;
142		range[k].end   = 0;
143		k--;
144	}
145	/* count it */
146	for (i = 0; i < az; i++) {
147		if (!range[i].end) {
148			nr_range = i;
149			break;
150		}
151	}
152
153	/* sort them */
154	sort(range, nr_range, sizeof(struct range), cmp_range, NULL);
155
156	return nr_range;
157}
158
159void sort_range(struct range *range, int nr_range)
160{
161	/* sort them */
162	sort(range, nr_range, sizeof(struct range), cmp_range, NULL);
163}
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Range add and subtract
  4 */
  5#include <linux/kernel.h>
  6#include <linux/init.h>
  7#include <linux/sort.h>
  8#include <linux/string.h>
  9#include <linux/range.h>
 10
 11int add_range(struct range *range, int az, int nr_range, u64 start, u64 end)
 12{
 13	if (start >= end)
 14		return nr_range;
 15
 16	/* Out of slots: */
 17	if (nr_range >= az)
 18		return nr_range;
 19
 20	range[nr_range].start = start;
 21	range[nr_range].end = end;
 22
 23	nr_range++;
 24
 25	return nr_range;
 26}
 27
 28int add_range_with_merge(struct range *range, int az, int nr_range,
 29		     u64 start, u64 end)
 30{
 31	int i;
 32
 33	if (start >= end)
 34		return nr_range;
 35
 36	/* get new start/end: */
 37	for (i = 0; i < nr_range; i++) {
 38		u64 common_start, common_end;
 39
 40		if (!range[i].end)
 41			continue;
 42
 43		common_start = max(range[i].start, start);
 44		common_end = min(range[i].end, end);
 45		if (common_start > common_end)
 46			continue;
 47
 48		/* new start/end, will add it back at last */
 49		start = min(range[i].start, start);
 50		end = max(range[i].end, end);
 51
 52		memmove(&range[i], &range[i + 1],
 53			(nr_range - (i + 1)) * sizeof(range[i]));
 54		range[nr_range - 1].start = 0;
 55		range[nr_range - 1].end   = 0;
 56		nr_range--;
 57		i--;
 58	}
 59
 60	/* Need to add it: */
 61	return add_range(range, az, nr_range, start, end);
 62}
 63
 64void subtract_range(struct range *range, int az, u64 start, u64 end)
 65{
 66	int i, j;
 67
 68	if (start >= end)
 69		return;
 70
 71	for (j = 0; j < az; j++) {
 72		if (!range[j].end)
 73			continue;
 74
 75		if (start <= range[j].start && end >= range[j].end) {
 76			range[j].start = 0;
 77			range[j].end = 0;
 78			continue;
 79		}
 80
 81		if (start <= range[j].start && end < range[j].end &&
 82		    range[j].start < end) {
 83			range[j].start = end;
 84			continue;
 85		}
 86
 87
 88		if (start > range[j].start && end >= range[j].end &&
 89		    range[j].end > start) {
 90			range[j].end = start;
 91			continue;
 92		}
 93
 94		if (start > range[j].start && end < range[j].end) {
 95			/* Find the new spare: */
 96			for (i = 0; i < az; i++) {
 97				if (range[i].end == 0)
 98					break;
 99			}
100			if (i < az) {
101				range[i].end = range[j].end;
102				range[i].start = end;
103			} else {
104				pr_err("%s: run out of slot in ranges\n",
105					__func__);
106			}
107			range[j].end = start;
108			continue;
109		}
110	}
111}
112
113static int cmp_range(const void *x1, const void *x2)
114{
115	const struct range *r1 = x1;
116	const struct range *r2 = x2;
117
118	if (r1->start < r2->start)
119		return -1;
120	if (r1->start > r2->start)
121		return 1;
122	return 0;
123}
124
125int clean_sort_range(struct range *range, int az)
126{
127	int i, j, k = az - 1, nr_range = az;
128
129	for (i = 0; i < k; i++) {
130		if (range[i].end)
131			continue;
132		for (j = k; j > i; j--) {
133			if (range[j].end) {
134				k = j;
135				break;
136			}
137		}
138		if (j == i)
139			break;
140		range[i].start = range[k].start;
141		range[i].end   = range[k].end;
142		range[k].start = 0;
143		range[k].end   = 0;
144		k--;
145	}
146	/* count it */
147	for (i = 0; i < az; i++) {
148		if (!range[i].end) {
149			nr_range = i;
150			break;
151		}
152	}
153
154	/* sort them */
155	sort(range, nr_range, sizeof(struct range), cmp_range, NULL);
156
157	return nr_range;
158}
159
160void sort_range(struct range *range, int nr_range)
161{
162	/* sort them */
163	sort(range, nr_range, sizeof(struct range), cmp_range, NULL);
164}