linux-sg2042/drivers/xen/biomerge.c

24 lines
609 B
C

#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 __BIOVEC_PHYS_MERGEABLE(vec1, vec2) &&
((bfn1 == bfn2) || ((bfn1+1) == 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);