[mirror_ubuntu-bionic-kernel.git] / drivers / xen / biomerge.c

// SPDX-License-Identifier: GPL-2.0
#include <linux/bio.h>
#include <linux/io.h>
#include <linux/export.h>
#include <xen/page.h>

bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
			       const struct bio_vec *vec2)
{
#if XEN_PAGE_SIZE == PAGE_SIZE
	unsigned long bfn1 = pfn_to_bfn(page_to_pfn(vec1->bv_page));
	unsigned long bfn2 = pfn_to_bfn(page_to_pfn(vec2->bv_page));

	return bfn1 + PFN_DOWN(vec1->bv_offset + vec1->bv_len) == bfn2;
#else
	/*
	 * XXX: Add support for merging bio_vec when using different page
	 * size in Xen and Linux.
	 */
	return 0;
#endif
}
EXPORT_SYMBOL(xen_biovec_phys_mergeable);
Commit	Line	Data
	1	// SPDX-License-Identifier: GPL-2.0
	2	#include <linux/bio.h>
	3	#include <linux/io.h>
	4	#include <linux/export.h>
	5	#include <xen/page.h>
	6
	7	bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
	8	const struct bio_vec *vec2)
	9	{
	10	#if XEN_PAGE_SIZE == PAGE_SIZE
	11	unsigned long bfn1 = pfn_to_bfn(page_to_pfn(vec1->bv_page));
	12	unsigned long bfn2 = pfn_to_bfn(page_to_pfn(vec2->bv_page));
	13
	14	return bfn1 + PFN_DOWN(vec1->bv_offset + vec1->bv_len) == bfn2;
	15	#else
	16	/*
	17	* XXX: Add support for merging bio_vec when using different page
	18	* size in Xen and Linux.
	19	*/
	20	return 0;
	21	#endif
	22	}
	23	EXPORT_SYMBOL(xen_biovec_phys_mergeable);