compat/backport-5.13.c

// SPDX-License-Identifier: GPL-2.0

#include <linux/export.h>
#include <linux/interrupt.h>
#include <linux/bitmap.h>
#include <linux/device.h>

#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT)
/*
 * Do not use in new code. Waiting for tasklets from atomic contexts is
 * error prone and should be avoided.
 */
void tasklet_unlock_spin_wait(struct tasklet_struct *t)
{
	while (test_bit(TASKLET_STATE_RUN, &(t)->state)) {
		if (IS_ENABLED(CONFIG_PREEMPT_RT)) {
			/*
			 * Prevent a live lock when current preempted soft
			 * interrupt processing or prevents ksoftirqd from
			 * running. If the tasklet runs on a different CPU
			 * then this has no effect other than doing the BH
			 * disable/enable dance for nothing.
			 */
			local_bh_disable();
			local_bh_enable();
		} else {
			cpu_relax();
		}
	}
}
EXPORT_SYMBOL_GPL(tasklet_unlock_spin_wait);
#endif

static void devm_bitmap_free(void *data)
{
	unsigned long *bitmap = data;

	bitmap_free(bitmap);
}

unsigned long *devm_bitmap_alloc(struct device *dev,
				 unsigned int nbits, gfp_t flags)
{
	unsigned long *bitmap;
	int ret;

	bitmap = bitmap_alloc(nbits, flags);
	if (!bitmap)
		return NULL;

	ret = devm_add_action_or_reset(dev, devm_bitmap_free, bitmap);
	if (ret)
		return NULL;

	return bitmap;
}
EXPORT_SYMBOL_GPL(devm_bitmap_alloc);

unsigned long *devm_bitmap_zalloc(struct device *dev,
				  unsigned int nbits, gfp_t flags)
{
	return devm_bitmap_alloc(dev, nbits, flags | __GFP_ZERO);
}
EXPORT_SYMBOL_GPL(devm_bitmap_zalloc);