| Message ID | 20190610221621.10938-4-hch@lst.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [01/17] mm: provide a print_vma_addr stub for !CONFIG_MMU | expand |
On 6/10/19 11:16 PM, Christoph Hellwig wrote: > We can't expose UAPI symbols differently based on CONFIG_ symbols, as > userspace won't have them available. Instead always define the flag, > but only repsect it based on the config option. ^^^^^^^ respect > > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > arch/xtensa/include/uapi/asm/mman.h | 6 +----- > include/uapi/asm-generic/mman-common.h | 8 +++----- > mm/nommu.c | 4 +++- > 3 files changed, 7 insertions(+), 11 deletions(-) FWIW: Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com> > > diff --git a/arch/xtensa/include/uapi/asm/mman.h b/arch/xtensa/include/uapi/asm/mman.h > index be726062412b..ebbb48842190 100644 > --- a/arch/xtensa/include/uapi/asm/mman.h > +++ b/arch/xtensa/include/uapi/asm/mman.h > @@ -56,12 +56,8 @@ > #define MAP_STACK 0x40000 /* give out an address that is best suited for process/thread stacks */ > #define MAP_HUGETLB 0x80000 /* create a huge page mapping */ > #define MAP_FIXED_NOREPLACE 0x100000 /* MAP_FIXED which doesn't unmap underlying mapping */ > -#ifdef CONFIG_MMAP_ALLOW_UNINITIALIZED > -# define MAP_UNINITIALIZED 0x4000000 /* For anonymous mmap, memory could be > +#define MAP_UNINITIALIZED 0x4000000 /* For anonymous mmap, memory could be > * uninitialized */ > -#else > -# define MAP_UNINITIALIZED 0x0 /* Don't support this flag */ > -#endif > > /* > * Flags for msync > diff --git a/include/uapi/asm-generic/mman-common.h b/include/uapi/asm-generic/mman-common.h > index abd238d0f7a4..cb556b430e71 100644 > --- a/include/uapi/asm-generic/mman-common.h > +++ b/include/uapi/asm-generic/mman-common.h > @@ -19,15 +19,13 @@ > #define MAP_TYPE 0x0f /* Mask for type of mapping */ > #define MAP_FIXED 0x10 /* Interpret addr exactly */ > #define MAP_ANONYMOUS 0x20 /* don't use a file */ > -#ifdef CONFIG_MMAP_ALLOW_UNINITIALIZED > -# define MAP_UNINITIALIZED 0x4000000 /* For anonymous mmap, memory could be uninitialized */ > -#else > -# define MAP_UNINITIALIZED 0x0 /* Don't support this flag */ > -#endif > > /* 0x0100 - 0x80000 flags are defined in asm-generic/mman.h */ > #define MAP_FIXED_NOREPLACE 0x100000 /* MAP_FIXED which doesn't unmap underlying mapping */ > > +#define MAP_UNINITIALIZED 0x4000000 /* For anonymous mmap, memory could be > + * uninitialized */ > + > /* > * Flags for mlock > */ > diff --git a/mm/nommu.c b/mm/nommu.c > index d8c02fbe03b5..ec75a0dffd4f 100644 > --- a/mm/nommu.c > +++ b/mm/nommu.c > @@ -1349,7 +1349,9 @@ unsigned long do_mmap(struct file *file, > add_nommu_region(region); > > /* clear anonymous mappings that don't ask for uninitialized data */ > - if (!vma->vm_file && !(flags & MAP_UNINITIALIZED)) > + if (!vma->vm_file && > + (!IS_ENABLED(CONFIG_MMAP_ALLOW_UNINITIALIZED) || > + !(flags & MAP_UNINITIALIZED))) > memset((void *)region->vm_start, 0, > region->vm_end - region->vm_start); > >
diff --git a/arch/xtensa/include/uapi/asm/mman.h b/arch/xtensa/include/uapi/asm/mman.h index be726062412b..ebbb48842190 100644 --- a/arch/xtensa/include/uapi/asm/mman.h +++ b/arch/xtensa/include/uapi/asm/mman.h @@ -56,12 +56,8 @@ #define MAP_STACK 0x40000 /* give out an address that is best suited for process/thread stacks */ #define MAP_HUGETLB 0x80000 /* create a huge page mapping */ #define MAP_FIXED_NOREPLACE 0x100000 /* MAP_FIXED which doesn't unmap underlying mapping */ -#ifdef CONFIG_MMAP_ALLOW_UNINITIALIZED -# define MAP_UNINITIALIZED 0x4000000 /* For anonymous mmap, memory could be +#define MAP_UNINITIALIZED 0x4000000 /* For anonymous mmap, memory could be * uninitialized */ -#else -# define MAP_UNINITIALIZED 0x0 /* Don't support this flag */ -#endif /* * Flags for msync diff --git a/include/uapi/asm-generic/mman-common.h b/include/uapi/asm-generic/mman-common.h index abd238d0f7a4..cb556b430e71 100644 --- a/include/uapi/asm-generic/mman-common.h +++ b/include/uapi/asm-generic/mman-common.h @@ -19,15 +19,13 @@ #define MAP_TYPE 0x0f /* Mask for type of mapping */ #define MAP_FIXED 0x10 /* Interpret addr exactly */ #define MAP_ANONYMOUS 0x20 /* don't use a file */ -#ifdef CONFIG_MMAP_ALLOW_UNINITIALIZED -# define MAP_UNINITIALIZED 0x4000000 /* For anonymous mmap, memory could be uninitialized */ -#else -# define MAP_UNINITIALIZED 0x0 /* Don't support this flag */ -#endif /* 0x0100 - 0x80000 flags are defined in asm-generic/mman.h */ #define MAP_FIXED_NOREPLACE 0x100000 /* MAP_FIXED which doesn't unmap underlying mapping */ +#define MAP_UNINITIALIZED 0x4000000 /* For anonymous mmap, memory could be + * uninitialized */ + /* * Flags for mlock */ diff --git a/mm/nommu.c b/mm/nommu.c index d8c02fbe03b5..ec75a0dffd4f 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -1349,7 +1349,9 @@ unsigned long do_mmap(struct file *file, add_nommu_region(region); /* clear anonymous mappings that don't ask for uninitialized data */ - if (!vma->vm_file && !(flags & MAP_UNINITIALIZED)) + if (!vma->vm_file && + (!IS_ENABLED(CONFIG_MMAP_ALLOW_UNINITIALIZED) || + !(flags & MAP_UNINITIALIZED))) memset((void *)region->vm_start, 0, region->vm_end - region->vm_start);
We can't expose UAPI symbols differently based on CONFIG_ symbols, as userspace won't have them available. Instead always define the flag, but only repsect it based on the config option. Signed-off-by: Christoph Hellwig <hch@lst.de> --- arch/xtensa/include/uapi/asm/mman.h | 6 +----- include/uapi/asm-generic/mman-common.h | 8 +++----- mm/nommu.c | 4 +++- 3 files changed, 7 insertions(+), 11 deletions(-)