Revision 6af10a33c501b0b5878476501143c2cfbbfd63a2 authored by Yufen Yu on 20 August 2020, 13:22:05 UTC, committed by Song Liu on 28 August 2020, 05:41:03 UTC
Commit 3b5408b98e4d ("md/raid5: support config stripe_size by sysfs
entry") make stripe_size as a configurable value. It just requires
stripe_size as multiple of 4KB.

In fact, we should make sure stripe_size as power of two. Otherwise,
stripe_shift which is the result of ilog2 can not represent the real
stripe_size. Then, stripe_hash() and stripe_hash_locks_hash() may
get unexpected value.

Fixes: 3b5408b98e4d ("md/raid5: support config stripe_size by sysfs entry")
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
1 parent 79e5dc5
Raw File
memcat_p.c
// SPDX-License-Identifier: GPL-2.0

#include <linux/slab.h>

/*
 * Merge two NULL-terminated pointer arrays into a newly allocated
 * array, which is also NULL-terminated. Nomenclature is inspired by
 * memset_p() and memcat() found elsewhere in the kernel source tree.
 */
void **__memcat_p(void **a, void **b)
{
	void **p = a, **new;
	int nr;

	/* count the elements in both arrays */
	for (nr = 0, p = a; *p; nr++, p++)
		;
	for (p = b; *p; nr++, p++)
		;
	/* one for the NULL-terminator */
	nr++;

	new = kmalloc_array(nr, sizeof(void *), GFP_KERNEL);
	if (!new)
		return NULL;

	/* nr -> last index; p points to NULL in b[] */
	for (nr--; nr >= 0; nr--, p = p == b ? &a[nr] : p - 1)
		new[nr] = *p;

	return new;
}
EXPORT_SYMBOL_GPL(__memcat_p);

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