Firstly, add the ability to determine if VMA flags are empty, that is no flags are set in a vma_flags_t value.
Next, add the ability to obtain the equivalent of the bitwise and of two vma_flags_t values, via vma_flags_and(). Next, add the ability to obtain the difference between two sets of VMA flags, that is the equivalent to the exclusive bitwise OR of the two sets of flags, via vma_flags_diff_pair(). vma_flags_xxx_mask() typically operates on a pointer to a vma_flags_t value, which is assumed to be an lvalue of some kind (such as a field in a struct or a stack variable) and an rvalue of some kind (typically a constant set of VMA flags obtained e.g. via mk_vma_flags() or equivalent). However vma_flags_diff_pair() is intended to operate on two lvalues, so use the _pair() suffix to make this clear. Finally, update VMA userland tests to add these helpers. We also port bitmap_xor() and __bitmap_xor() to the tools/ headers and source to allow the tests to work with vma_flags_diff_pair(). Signed-off-by: Lorenzo Stoakes (Oracle) <[email protected]> --- include/linux/mm.h | 60 ++++++++++++++++++++++++++++----- include/linux/mm_types.h | 8 +++++ tools/include/linux/bitmap.h | 13 +++++++ tools/lib/bitmap.c | 10 ++++++ tools/testing/vma/include/dup.h | 36 +++++++++++++++++++- 5 files changed, 117 insertions(+), 10 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 4c4fd55fc823..3d82e53875fa 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1055,6 +1055,19 @@ static __always_inline vma_flags_t __mk_vma_flags(size_t count, return flags; } +/* + * Helper macro which bitwise-or combines the specified input flags into a + * vma_flags_t bitmap value. E.g.: + * + * vma_flags_t flags = mk_vma_flags(VMA_IO_BIT, VMA_PFNMAP_BIT, + * VMA_DONTEXPAND_BIT, VMA_DONTDUMP_BIT); + * + * The compiler cleverly optimises away all of the work and this ends up being + * equivalent to aggregating the values manually. + */ +#define mk_vma_flags(...) __mk_vma_flags(COUNT_ARGS(__VA_ARGS__), \ + (const vma_flag_t []){__VA_ARGS__}) + /* * Test whether a specific VMA flag is set, e.g.: * @@ -1069,17 +1082,30 @@ static __always_inline bool vma_flags_test(const vma_flags_t *flags, } /* - * Helper macro which bitwise-or combines the specified input flags into a - * vma_flags_t bitmap value. E.g.: - * - * vma_flags_t flags = mk_vma_flags(VMA_IO_BIT, VMA_PFNMAP_BIT, - * VMA_DONTEXPAND_BIT, VMA_DONTDUMP_BIT); + * Obtain a set of VMA flags which contain the overlapping flags contained + * within flags and to_and. + */ +static __always_inline vma_flags_t vma_flags_and_mask(const vma_flags_t *flags, + vma_flags_t to_and) +{ + vma_flags_t dst; + unsigned long *bitmap_dst = dst.__vma_flags; + const unsigned long *bitmap = flags->__vma_flags; + const unsigned long *bitmap_to_and = to_and.__vma_flags; + + bitmap_and(bitmap_dst, bitmap, bitmap_to_and, NUM_VMA_FLAG_BITS); + return dst; +} + +/* + * Obtain a set of VMA flags which contains the specified overlapping flags, + * e.g.: * - * The compiler cleverly optimises away all of the work and this ends up being - * equivalent to aggregating the values manually. + * vma_flags_t read_flags = vma_flags_and(&flags, VMA_READ_BIT, + * VMA_MAY_READ_BIT); */ -#define mk_vma_flags(...) __mk_vma_flags(COUNT_ARGS(__VA_ARGS__), \ - (const vma_flag_t []){__VA_ARGS__}) +#define vma_flags_and(flags, ...) \ + vma_flags_and_mask(flags, mk_vma_flags(__VA_ARGS__)) /* Test each of to_test flags in flags, non-atomically. */ static __always_inline bool vma_flags_test_any_mask(const vma_flags_t *flags, @@ -1153,6 +1179,22 @@ static __always_inline void vma_flags_clear_mask(vma_flags_t *flags, #define vma_flags_clear(flags, ...) \ vma_flags_clear_mask(flags, mk_vma_flags(__VA_ARGS__)) +/* + * Obtain a VMA flags value containing those flags that are present in flags or + * flags_other but not in both. + */ +static __always_inline vma_flags_t vma_flags_diff_pair(const vma_flags_t *flags, + const vma_flags_t *flags_other) +{ + vma_flags_t dst; + const unsigned long *bitmap_other = flags_other->__vma_flags; + const unsigned long *bitmap = flags->__vma_flags; + unsigned long *bitmap_dst = dst.__vma_flags; + + bitmap_xor(bitmap_dst, bitmap, bitmap_other, NUM_VMA_FLAG_BITS); + return dst; +} + /* * Helper to test that ALL specified flags are set in a VMA. * diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 3944b51ebac6..ad414ff2d815 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -870,6 +870,14 @@ typedef struct { #define EMPTY_VMA_FLAGS ((vma_flags_t){ }) +/* Are no flags set in the specified VMA flags? */ +static __always_inline bool vma_flags_empty(vma_flags_t *flags) +{ + unsigned long *bitmap = flags->__vma_flags; + + return bitmap_empty(bitmap, NUM_VMA_FLAG_BITS); +} + /* * Describes a VMA that is about to be mmap()'ed. Drivers may choose to * manipulate mutable fields which will cause those fields to be updated in the diff --git a/tools/include/linux/bitmap.h b/tools/include/linux/bitmap.h index 250883090a5d..845eda759f67 100644 --- a/tools/include/linux/bitmap.h +++ b/tools/include/linux/bitmap.h @@ -28,6 +28,8 @@ bool __bitmap_subset(const unsigned long *bitmap1, const unsigned long *bitmap2, unsigned int nbits); bool __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1, const unsigned long *bitmap2, unsigned int nbits); +void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1, + const unsigned long *bitmap2, unsigned int nbits); #define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) & (BITS_PER_LONG - 1))) #define BITMAP_LAST_WORD_MASK(nbits) (~0UL >> (-(nbits) & (BITS_PER_LONG - 1))) @@ -209,4 +211,15 @@ static inline void bitmap_clear(unsigned long *map, unsigned int start, else __bitmap_clear(map, start, nbits); } + +static __always_inline +void bitmap_xor(unsigned long *dst, const unsigned long *src1, + const unsigned long *src2, unsigned int nbits) +{ + if (small_const_nbits(nbits)) + *dst = *src1 ^ *src2; + else + __bitmap_xor(dst, src1, src2, nbits); +} + #endif /* _TOOLS_LINUX_BITMAP_H */ diff --git a/tools/lib/bitmap.c b/tools/lib/bitmap.c index aa83d22c45e3..fedc9070f0e4 100644 --- a/tools/lib/bitmap.c +++ b/tools/lib/bitmap.c @@ -169,3 +169,13 @@ bool __bitmap_subset(const unsigned long *bitmap1, return false; return true; } + +void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1, + const unsigned long *bitmap2, unsigned int bits) +{ + unsigned int k; + unsigned int nr = BITS_TO_LONGS(bits); + + for (k = 0; k < nr; k++) + dst[k] = bitmap1[k] ^ bitmap2[k]; +} diff --git a/tools/testing/vma/include/dup.h b/tools/testing/vma/include/dup.h index 5eb313beb43d..2f53c27ddb21 100644 --- a/tools/testing/vma/include/dup.h +++ b/tools/testing/vma/include/dup.h @@ -419,6 +419,13 @@ struct vma_iterator { #define EMPTY_VMA_FLAGS ((vma_flags_t){ }) +static __always_inline bool vma_flags_empty(vma_flags_t *flags) +{ + unsigned long *bitmap = flags->__vma_flags; + + return bitmap_empty(bitmap, NUM_VMA_FLAG_BITS); +} + /* What action should be taken after an .mmap_prepare call is complete? */ enum mmap_action_type { MMAP_NOTHING, /* Mapping is complete, no further action. */ @@ -852,6 +859,21 @@ static __always_inline bool vma_flags_test(const vma_flags_t *flags, return test_bit((__force int)bit, bitmap); } +static __always_inline vma_flags_t vma_flags_and_mask(const vma_flags_t *flags, + vma_flags_t to_and) +{ + vma_flags_t dst; + unsigned long *bitmap_dst = dst.__vma_flags; + const unsigned long *bitmap = flags->__vma_flags; + const unsigned long *bitmap_to_and = to_and.__vma_flags; + + bitmap_and(bitmap_dst, bitmap, bitmap_to_and, NUM_VMA_FLAG_BITS); + return dst; +} + +#define vma_flags_and(flags, ...) \ + vma_flags_and_mask(flags, mk_vma_flags(__VA_ARGS__)) + static __always_inline bool vma_flags_test_any_mask(const vma_flags_t *flags, vma_flags_t to_test) { @@ -898,8 +920,20 @@ static __always_inline void vma_flags_clear_mask(vma_flags_t *flags, vma_flags_t #define vma_flags_clear(flags, ...) \ vma_flags_clear_mask(flags, mk_vma_flags(__VA_ARGS__)) +static __always_inline vma_flags_t vma_flags_diff_pair(const vma_flags_t *flags, + const vma_flags_t *flags_other) +{ + vma_flags_t dst; + const unsigned long *bitmap_other = flags_other->__vma_flags; + const unsigned long *bitmap = flags->__vma_flags; + unsigned long *bitmap_dst = dst.__vma_flags; + + bitmap_xor(bitmap_dst, bitmap, bitmap_other, NUM_VMA_FLAG_BITS); + return dst; +} + static inline bool vma_test_all_mask(const struct vm_area_struct *vma, - vma_flags_t flags) + vma_flags_t flags) { return vma_flags_test_all_mask(&vma->flags, flags); } -- 2.53.0
