parisc: led driver requires CONFIG_VM_EVENT_COUNTERS
[linux-2.6/btrfs-unstable.git] / drivers / xen / biomerge.c
blob0edb91c0de6bf2b69d6de3ec41d43d38b5d823b5
1 #include <linux/bio.h>
2 #include <linux/io.h>
3 #include <linux/export.h>
4 #include <xen/page.h>
6 bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
7 const struct bio_vec *vec2)
9 unsigned long mfn1 = pfn_to_mfn(page_to_pfn(vec1->bv_page));
10 unsigned long mfn2 = pfn_to_mfn(page_to_pfn(vec2->bv_page));
12 return __BIOVEC_PHYS_MERGEABLE(vec1, vec2) &&
13 ((mfn1 == mfn2) || ((mfn1+1) == mfn2));
15 EXPORT_SYMBOL(xen_biovec_phys_mergeable);