Now we have updated all users of mm->flags to use the bitmap accessors, repalce it with the bitmap version entirely.
We are then able to move to having 64 bits of mm->flags on both 32-bit and 64-bit architectures. We also update the VMA userland tests to ensure that everything remains functional there. No functional changes intended, other than there now being 64 bits of available mm_struct flags. Signed-off-by: Lorenzo Stoakes <lorenzo.stoa...@oracle.com> --- include/linux/mm.h | 12 ++++++------ include/linux/mm_types.h | 14 +++++--------- include/linux/sched/coredump.h | 2 +- tools/testing/vma/vma_internal.h | 19 +++++++++++++++++-- 4 files changed, 29 insertions(+), 18 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 34311ebe62cc..b61e2d4858cf 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -724,32 +724,32 @@ static inline void assert_fault_locked(struct vm_fault *vmf) static inline bool mm_flags_test(int flag, const struct mm_struct *mm) { - return test_bit(flag, ACCESS_PRIVATE(&mm->_flags, __mm_flags)); + return test_bit(flag, ACCESS_PRIVATE(&mm->flags, __mm_flags)); } static inline bool mm_flags_test_and_set(int flag, struct mm_struct *mm) { - return test_and_set_bit(flag, ACCESS_PRIVATE(&mm->_flags, __mm_flags)); + return test_and_set_bit(flag, ACCESS_PRIVATE(&mm->flags, __mm_flags)); } static inline bool mm_flags_test_and_clear(int flag, struct mm_struct *mm) { - return test_and_clear_bit(flag, ACCESS_PRIVATE(&mm->_flags, __mm_flags)); + return test_and_clear_bit(flag, ACCESS_PRIVATE(&mm->flags, __mm_flags)); } static inline void mm_flags_set(int flag, struct mm_struct *mm) { - set_bit(flag, ACCESS_PRIVATE(&mm->_flags, __mm_flags)); + set_bit(flag, ACCESS_PRIVATE(&mm->flags, __mm_flags)); } static inline void mm_flags_clear(int flag, struct mm_struct *mm) { - clear_bit(flag, ACCESS_PRIVATE(&mm->_flags, __mm_flags)); + clear_bit(flag, ACCESS_PRIVATE(&mm->flags, __mm_flags)); } static inline void mm_flags_clear_all(struct mm_struct *mm) { - bitmap_zero(ACCESS_PRIVATE(&mm->_flags, __mm_flags), NUM_MM_FLAG_BITS); + bitmap_zero(ACCESS_PRIVATE(&mm->flags, __mm_flags), NUM_MM_FLAG_BITS); } extern const struct vm_operations_struct vma_dummy_vm_ops; diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 25577ab39094..47d2e4598acd 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -932,7 +932,7 @@ struct mm_cid { * Opaque type representing current mm_struct flag state. Must be accessed via * mm_flags_xxx() helper functions. */ -#define NUM_MM_FLAG_BITS BITS_PER_LONG +#define NUM_MM_FLAG_BITS (64) typedef struct { __private DECLARE_BITMAP(__mm_flags, NUM_MM_FLAG_BITS); } mm_flags_t; @@ -1119,11 +1119,7 @@ struct mm_struct { /* Architecture-specific MM context */ mm_context_t context; - /* Temporary union while we convert users to mm_flags_t. */ - union { - unsigned long flags; /* Must use atomic bitops to access */ - mm_flags_t _flags; /* Must use mm_flags_* helpers to access */ - }; + mm_flags_t flags; /* Must use mm_flags_* hlpers to access */ #ifdef CONFIG_AIO spinlock_t ioctx_lock; @@ -1236,7 +1232,7 @@ struct mm_struct { /* Read the first system word of mm flags, non-atomically. */ static inline unsigned long __mm_flags_get_word(struct mm_struct *mm) { - unsigned long *bitmap = ACCESS_PRIVATE(&mm->_flags, __mm_flags); + unsigned long *bitmap = ACCESS_PRIVATE(&mm->flags, __mm_flags); return bitmap_read(bitmap, 0, BITS_PER_LONG); } @@ -1245,7 +1241,7 @@ static inline unsigned long __mm_flags_get_word(struct mm_struct *mm) static inline void __mm_flags_set_word(struct mm_struct *mm, unsigned long value) { - unsigned long *bitmap = ACCESS_PRIVATE(&mm->_flags, __mm_flags); + unsigned long *bitmap = ACCESS_PRIVATE(&mm->flags, __mm_flags); bitmap_copy(bitmap, &value, BITS_PER_LONG); } @@ -1253,7 +1249,7 @@ static inline void __mm_flags_set_word(struct mm_struct *mm, /* Obtain a read-only view of the bitmap. */ static inline const unsigned long *__mm_flags_get_bitmap(const struct mm_struct *mm) { - return (const unsigned long *)ACCESS_PRIVATE(&mm->_flags, __mm_flags); + return (const unsigned long *)ACCESS_PRIVATE(&mm->flags, __mm_flags); } #define MM_MT_FLAGS (MT_FLAGS_ALLOC_RANGE | MT_FLAGS_LOCK_EXTERN | \ diff --git a/include/linux/sched/coredump.h b/include/linux/sched/coredump.h index 19ecfcceb27a..079ae5a97480 100644 --- a/include/linux/sched/coredump.h +++ b/include/linux/sched/coredump.h @@ -20,7 +20,7 @@ static inline unsigned long __mm_flags_get_dumpable(struct mm_struct *mm) static inline void __mm_flags_set_mask_dumpable(struct mm_struct *mm, int value) { - unsigned long *bitmap = ACCESS_PRIVATE(&mm->_flags, __mm_flags); + unsigned long *bitmap = ACCESS_PRIVATE(&mm->flags, __mm_flags); set_mask_bits(bitmap, MMF_DUMPABLE_MASK, value); } diff --git a/tools/testing/vma/vma_internal.h b/tools/testing/vma/vma_internal.h index cb1c2a8afe26..f13354bf0a1e 100644 --- a/tools/testing/vma/vma_internal.h +++ b/tools/testing/vma/vma_internal.h @@ -249,6 +249,14 @@ struct mutex {}; #define DEFINE_MUTEX(mutexname) \ struct mutex mutexname = {} +#define DECLARE_BITMAP(name, bits) \ + unsigned long name[BITS_TO_LONGS(bits)] + +#define NUM_MM_FLAG_BITS (64) +typedef struct { + __private DECLARE_BITMAP(__mm_flags, NUM_MM_FLAG_BITS); +} mm_flags_t; + struct mm_struct { struct maple_tree mm_mt; int map_count; /* number of VMAs */ @@ -260,7 +268,7 @@ struct mm_struct { unsigned long def_flags; - unsigned long flags; /* Must use atomic bitops to access */ + mm_flags_t flags; /* Must use mm_flags_* helpers to access */ }; struct vm_area_struct; @@ -1333,6 +1341,13 @@ static inline void userfaultfd_unmap_complete(struct mm_struct *mm, { } +# define ACCESS_PRIVATE(p, member) ((p)->member) + +static inline bool mm_flags_test(int flag, const struct mm_struct *mm) +{ + return test_bit(flag, ACCESS_PRIVATE(&mm->flags, __mm_flags)); +} + /* * Denies creating a writable executable mapping or gaining executable permissions. * @@ -1363,7 +1378,7 @@ static inline void userfaultfd_unmap_complete(struct mm_struct *mm, static inline bool map_deny_write_exec(unsigned long old, unsigned long new) { /* If MDWE is disabled, we have nothing to deny. */ - if (!test_bit(MMF_HAS_MDWE, ¤t->mm->flags)) + if (mm_flags_test(MMF_HAS_MDWE, current->mm)) return false; /* If the new VMA is not executable, we have nothing to deny. */ -- 2.50.1