[linux-block.git] / drivers / xen / biomerge.c

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

/* check if @page can be merged with 'vec1' */
bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
			       const struct page *page)
{
#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(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 false;
#endif
}
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
d8e04206	2	#include <linux/bio.h>
9ef9b20b	3	#include <linux/export.h>
c39ae60d	4	#include <xen/xen.h>
d8e04206 JF	5	#include <xen/page.h>
d8e04206 JF	6
0383ad43	7	/* check if @page can be merged with 'vec1' */
d8e04206	8	bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
0383ad43	9	const struct page *page)
d8e04206	10	{
36f8abd3	11	#if XEN_PAGE_SIZE == PAGE_SIZE
32e09870	12	unsigned long bfn1 = pfn_to_bfn(page_to_pfn(vec1->bv_page));
0383ad43	13	unsigned long bfn2 = pfn_to_bfn(page_to_pfn(page));
d8e04206	14
462cdace	15	return bfn1 + PFN_DOWN(vec1->bv_offset + vec1->bv_len) == bfn2;
36f8abd3 JG	16	#else
	17	/*
	18	* XXX: Add support for merging bio_vec when using different page
	19	* size in Xen and Linux.
	20	*/
bf06bad9	21	return false;
36f8abd3	22	#endif
d8e04206	23	}