get_mm_addr_key() helper returns the pkey associated with an address corresponding to a given mm_struct.
Signed-off-by: Ram Pai linuxram@us.ibm.com --- arch/powerpc/include/asm/mmu.h | 9 +++++++++ arch/powerpc/mm/hash_utils_64.c | 24 ++++++++++++++++++++++++ 2 files changed, 33 insertions(+), 0 deletions(-)
diff --git a/arch/powerpc/include/asm/mmu.h b/arch/powerpc/include/asm/mmu.h index 6364f5c..bb38312 100644 --- a/arch/powerpc/include/asm/mmu.h +++ b/arch/powerpc/include/asm/mmu.h @@ -260,6 +260,15 @@ static inline bool early_radix_enabled(void) } #endif
+#ifdef CONFIG_PPC_MEM_KEYS +extern u16 get_mm_addr_key(struct mm_struct *mm, unsigned long address); +#else +static inline u16 get_mm_addr_key(struct mm_struct *mm, unsigned long address) +{ + return 0; +} +#endif /* CONFIG_PPC_MEM_KEYS */ + #endif /* !__ASSEMBLY__ */
/* The kernel use the constants below to index in the page sizes array. diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c index dc0f76e..1e1c03b 100644 --- a/arch/powerpc/mm/hash_utils_64.c +++ b/arch/powerpc/mm/hash_utils_64.c @@ -1573,6 +1573,30 @@ void hash_preload(struct mm_struct *mm, unsigned long ea, local_irq_restore(flags); }
+#ifdef CONFIG_PPC_MEM_KEYS +/* + * Return the protection key associated with the given address and the + * mm_struct. + */ +u16 get_mm_addr_key(struct mm_struct *mm, unsigned long address) +{ + pte_t *ptep; + u16 pkey = 0; + unsigned long flags; + + if (!mm || !mm->pgd) + return 0; + + local_irq_save(flags); + ptep = find_linux_pte(mm->pgd, address, NULL, NULL); + if (ptep) + pkey = pte_to_pkey_bits(pte_val(READ_ONCE(*ptep))); + local_irq_restore(flags); + + return pkey; +} +#endif /* CONFIG_PPC_MEM_KEYS */ + #ifdef CONFIG_PPC_TRANSACTIONAL_MEM static inline void tm_flush_hash_page(int local) {