On Wed, Aug 16, 2017 at 12:44:22AM -0700, Dan Williams wrote: > diff --git a/include/linux/mman.h b/include/linux/mman.h > index c8367041fafd..0e1de42c836f 100644 > --- a/include/linux/mman.h > +++ b/include/linux/mman.h > @@ -7,6 +7,40 @@ > #include <linux/atomic.h> > #include <uapi/linux/mman.h> > > +#ifndef MAP_32BIT > +#define MAP_32BIT 0 > +#endif > +#ifndef MAP_HUGE_2MB > +#define MAP_HUGE_2MB 0 > +#endif > +#ifndef MAP_HUGE_1GB > +#define MAP_HUGE_1GB 0 > +#endif > + > +/* > + * The historical set of flags that all mmap implementations implicitly > + * support when file_operations.mmap_supported_mask is zero. > + */ > +#define LEGACY_MAP_SUPPORTED_MASK (MAP_SHARED \ > + | MAP_PRIVATE \ > + | MAP_FIXED \ > + | MAP_ANONYMOUS \ > + | MAP_UNINITIALIZED \ > + | MAP_GROWSDOWN \ > + | MAP_DENYWRITE \ > + | MAP_EXECUTABLE \ > + | MAP_LOCKED \ > + | MAP_NORESERVE \ > + | MAP_POPULATE \ > + | MAP_NONBLOCK \ > + | MAP_STACK \ > + | MAP_HUGETLB \ > + | MAP_32BIT \ > + | MAP_HUGE_2MB \ > + | MAP_HUGE_1GB) > + > +#define MAP_SUPPORTED_MASK (LEGACY_MAP_SUPPORTED_MASK) > + > extern int sysctl_overcommit_memory; > extern int sysctl_overcommit_ratio; > extern unsigned long sysctl_overcommit_kbytes; Since we looking into mmap(2) ABI, maybe we should consider re-defining MAP_DENYWRITE and MAP_EXECUTABLE as 0 in hope that we would be able to re-use these bits in the future? These flags are ignored now anyway. -- Kirill A. Shutemov
