• Greg Kroah-Hartman's avatar
    License cleanup: add SPDX GPL-2.0 license identifier to files with no license · b2441318
    Greg Kroah-Hartman authored
    Many source files in the tree are missing licensing information, which
    makes it harder for compliance tools to determine the correct license.
    
    By default all files without license information are under the default
    license of the kernel, which is GPL version 2.
    
    Update the files which contain no license information with the 'GPL-2.0'
    SPDX license identifier.  The SPDX identifier is a legally binding
    shorthand, which can be used instead of the full boiler plate text.
    
    This patch is based on work done by Thomas Gleixner and Kate Stewart and
    Philippe Ombredanne.
    
    How this work was done:
    
    Patches were generated and checked against linux-4.14-rc6 for a subset of
    the use cases:
     - file had no licensing information it it.
     - file was a */uapi/* one with no licensing information in it,
     - file was a */uapi/* one with existing licensing information,
    
    Further patches will be generated in subsequent months to fix up cases
    where non-standard...
    b2441318
range.c 3.01 KB
// SPDX-License-Identifier: GPL-2.0
/*
 * Range add and subtract
 */
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/sort.h>
#include <linux/string.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;

	/* get new start/end: */
	for (i = 0; i < nr_range; i++) {
		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;

		/* new start/end, will add it back at last */
		start = min(range[i].start, start);
		end = max(range[i].end, end);

		memmove(&range[i], &range[i + 1],
			(nr_range - (i + 1)) * sizeof(range[i]));
		range[nr_range - 1].start = 0;
		range[nr_range - 1].end   = 0;
		nr_range--;
		i--;
	}

	/* 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 {
				pr_err("%s: run out of slot in ranges\n",
					__func__);
			}
			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;

	if (r1->start < r2->start)
		return -1;
	if (r1->start > r2->start)
		return 1;
	return 0;
}

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);
}