| Message ID | 20210617093032.103097-4-dja@axtens.net (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KASAN core changes for ppc64 radix KASAN | expand |
On Thu, Jun 17, 2021 at 12:30 PM Daniel Axtens <dja@axtens.net> wrote: > > Commit c65e774fb3f6 ("x86/mm: Make PGDIR_SHIFT and PTRS_PER_P4D variable") > made PTRS_PER_P4D variable on x86 and introduced MAX_PTRS_PER_P4D as a > constant for cases which need a compile-time constant (e.g. fixed-size > arrays). > > powerpc likewise has boot-time selectable MMU features which can cause > other mm "constants" to vary. For KASAN, we have some static > PTE/PMD/PUD/P4D arrays so we need compile-time maximums for all these > constants. Extend the MAX_PTRS_PER_ idiom, and place default definitions > in include/pgtable.h. These define MAX_PTRS_PER_x to be PTRS_PER_x unless > an architecture has defined MAX_PTRS_PER_x in its arch headers. > > Clean up pgtable-nop4d.h and s390's MAX_PTRS_PER_P4D definitions while > we're at it: both can just pick up the default now. > > Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> > Reviewed-by: Marco Elver <elver@google.com> > Signed-off-by: Daniel Axtens <dja@axtens.net> > > --- > > s390 was compile tested only. > --- > arch/s390/include/asm/pgtable.h | 2 -- > include/asm-generic/pgtable-nop4d.h | 1 - > include/linux/pgtable.h | 22 ++++++++++++++++++++++ > 3 files changed, 22 insertions(+), 3 deletions(-) > > diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h > index 7c66ae5d7e32..cf05954ce013 100644 > --- a/arch/s390/include/asm/pgtable.h > +++ b/arch/s390/include/asm/pgtable.h > @@ -342,8 +342,6 @@ static inline int is_module_addr(void *addr) > #define PTRS_PER_P4D _CRST_ENTRIES > #define PTRS_PER_PGD _CRST_ENTRIES > > -#define MAX_PTRS_PER_P4D PTRS_PER_P4D > - > /* > * Segment table and region3 table entry encoding > * (R = read-only, I = invalid, y = young bit): > diff --git a/include/asm-generic/pgtable-nop4d.h b/include/asm-generic/pgtable-nop4d.h > index ce2cbb3c380f..2f6b1befb129 100644 > --- a/include/asm-generic/pgtable-nop4d.h > +++ b/include/asm-generic/pgtable-nop4d.h > @@ -9,7 +9,6 @@ > typedef struct { pgd_t pgd; } p4d_t; > > #define P4D_SHIFT PGDIR_SHIFT > -#define MAX_PTRS_PER_P4D 1 > #define PTRS_PER_P4D 1 > #define P4D_SIZE (1UL << P4D_SHIFT) > #define P4D_MASK (~(P4D_SIZE-1)) > diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h > index 9e6f71265f72..69700e3e615f 100644 > --- a/include/linux/pgtable.h > +++ b/include/linux/pgtable.h > @@ -1625,4 +1625,26 @@ typedef unsigned int pgtbl_mod_mask; > #define pte_leaf_size(x) PAGE_SIZE > #endif > > +/* > + * Some architectures have MMUs that are configurable or selectable at boot > + * time. These lead to variable PTRS_PER_x. For statically allocated arrays it > + * helps to have a static maximum value. > + */ > + > +#ifndef MAX_PTRS_PER_PTE > +#define MAX_PTRS_PER_PTE PTRS_PER_PTE > +#endif > + > +#ifndef MAX_PTRS_PER_PMD > +#define MAX_PTRS_PER_PMD PTRS_PER_PMD > +#endif > + > +#ifndef MAX_PTRS_PER_PUD > +#define MAX_PTRS_PER_PUD PTRS_PER_PUD > +#endif > + > +#ifndef MAX_PTRS_PER_P4D > +#define MAX_PTRS_PER_P4D PTRS_PER_P4D > +#endif > + > #endif /* _LINUX_PGTABLE_H */ > -- > 2.30.2 > Acked-by: Andrey Konovalov <andreyknvl@gmail.com>
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index 7c66ae5d7e32..cf05954ce013 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -342,8 +342,6 @@ static inline int is_module_addr(void *addr) #define PTRS_PER_P4D _CRST_ENTRIES #define PTRS_PER_PGD _CRST_ENTRIES -#define MAX_PTRS_PER_P4D PTRS_PER_P4D - /* * Segment table and region3 table entry encoding * (R = read-only, I = invalid, y = young bit): diff --git a/include/asm-generic/pgtable-nop4d.h b/include/asm-generic/pgtable-nop4d.h index ce2cbb3c380f..2f6b1befb129 100644 --- a/include/asm-generic/pgtable-nop4d.h +++ b/include/asm-generic/pgtable-nop4d.h @@ -9,7 +9,6 @@ typedef struct { pgd_t pgd; } p4d_t; #define P4D_SHIFT PGDIR_SHIFT -#define MAX_PTRS_PER_P4D 1 #define PTRS_PER_P4D 1 #define P4D_SIZE (1UL << P4D_SHIFT) #define P4D_MASK (~(P4D_SIZE-1)) diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h index 9e6f71265f72..69700e3e615f 100644 --- a/include/linux/pgtable.h +++ b/include/linux/pgtable.h @@ -1625,4 +1625,26 @@ typedef unsigned int pgtbl_mod_mask; #define pte_leaf_size(x) PAGE_SIZE #endif +/* + * Some architectures have MMUs that are configurable or selectable at boot + * time. These lead to variable PTRS_PER_x. For statically allocated arrays it + * helps to have a static maximum value. + */ + +#ifndef MAX_PTRS_PER_PTE +#define MAX_PTRS_PER_PTE PTRS_PER_PTE +#endif + +#ifndef MAX_PTRS_PER_PMD +#define MAX_PTRS_PER_PMD PTRS_PER_PMD +#endif + +#ifndef MAX_PTRS_PER_PUD +#define MAX_PTRS_PER_PUD PTRS_PER_PUD +#endif + +#ifndef MAX_PTRS_PER_P4D +#define MAX_PTRS_PER_P4D PTRS_PER_P4D +#endif + #endif /* _LINUX_PGTABLE_H */
Commit c65e774fb3f6 ("x86/mm: Make PGDIR_SHIFT and PTRS_PER_P4D variable") made PTRS_PER_P4D variable on x86 and introduced MAX_PTRS_PER_P4D as a constant for cases which need a compile-time constant (e.g. fixed-size arrays). powerpc likewise has boot-time selectable MMU features which can cause other mm "constants" to vary. For KASAN, we have some static PTE/PMD/PUD/P4D arrays so we need compile-time maximums for all these constants. Extend the MAX_PTRS_PER_ idiom, and place default definitions in include/pgtable.h. These define MAX_PTRS_PER_x to be PTRS_PER_x unless an architecture has defined MAX_PTRS_PER_x in its arch headers. Clean up pgtable-nop4d.h and s390's MAX_PTRS_PER_P4D definitions while we're at it: both can just pick up the default now. Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Marco Elver <elver@google.com> Signed-off-by: Daniel Axtens <dja@axtens.net> --- s390 was compile tested only. --- arch/s390/include/asm/pgtable.h | 2 -- include/asm-generic/pgtable-nop4d.h | 1 - include/linux/pgtable.h | 22 ++++++++++++++++++++++ 3 files changed, 22 insertions(+), 3 deletions(-)