| Message ID | 20240603061023.269738-7-zhenzhong.duan@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add a host IOMMU device abstraction to check with vIOMMU | expand |
On 6/3/24 08:10, Zhenzhong Duan wrote: > This helper get the highest 1 bit position of the upper bound. > > If the range is empty or upper bound is zero, -1 is returned. > > Suggested-by: Cédric Le Goater <clg@redhat.com> > Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Eric > --- > include/qemu/range.h | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/include/qemu/range.h b/include/qemu/range.h > index 205e1da76d..4ce694a398 100644 > --- a/include/qemu/range.h > +++ b/include/qemu/range.h > @@ -20,6 +20,8 @@ > #ifndef QEMU_RANGE_H > #define QEMU_RANGE_H > > +#include "qemu/bitops.h" > + > /* > * Operations on 64 bit address ranges. > * Notes: > @@ -217,6 +219,15 @@ static inline int ranges_overlap(uint64_t first1, uint64_t len1, > return !(last2 < first1 || last1 < first2); > } > > +/* Get highest non-zero bit position of a range */ > +static inline int range_get_last_bit(Range *range) > +{ > + if (range_is_empty(range)) { > + return -1; > + } > + return 63 - clz64(range->upb); > +} > + > /* > * Return -1 if @a < @b, 1 @a > @b, and 0 if they touch or overlap. > * Both @a and @b must not be empty.
diff --git a/include/qemu/range.h b/include/qemu/range.h index 205e1da76d..4ce694a398 100644 --- a/include/qemu/range.h +++ b/include/qemu/range.h @@ -20,6 +20,8 @@ #ifndef QEMU_RANGE_H #define QEMU_RANGE_H +#include "qemu/bitops.h" + /* * Operations on 64 bit address ranges. * Notes: @@ -217,6 +219,15 @@ static inline int ranges_overlap(uint64_t first1, uint64_t len1, return !(last2 < first1 || last1 < first2); } +/* Get highest non-zero bit position of a range */ +static inline int range_get_last_bit(Range *range) +{ + if (range_is_empty(range)) { + return -1; + } + return 63 - clz64(range->upb); +} + /* * Return -1 if @a < @b, 1 @a > @b, and 0 if they touch or overlap. * Both @a and @b must not be empty.
This helper get the highest 1 bit position of the upper bound. If the range is empty or upper bound is zero, -1 is returned. Suggested-by: Cédric Le Goater <clg@redhat.com> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com> --- include/qemu/range.h | 11 +++++++++++ 1 file changed, 11 insertions(+)