On 07/06/2017 02:52 AM, Ram Pai wrote:
> get_pte_pkey() helper returns the pkey associated with
> a address corresponding to a given mm_struct.
>
> Signed-off-by: Ram Pai <linuxram@xxxxxxxxxx>
> ---
> arch/powerpc/include/asm/book3s/64/mmu-hash.h | 5 ++++
> arch/powerpc/mm/hash_utils_64.c | 28 +++++++++++++++++++++++++
> 2 files changed, 33 insertions(+), 0 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/book3s/64/mmu-hash.h b/arch/powerpc/include/asm/book3s/64/mmu-hash.h
> index f7a6ed3..369f9ff 100644
> --- a/arch/powerpc/include/asm/book3s/64/mmu-hash.h
> +++ b/arch/powerpc/include/asm/book3s/64/mmu-hash.h
> @@ -450,6 +450,11 @@ extern int hash_page(unsigned long ea, unsigned long access, unsigned long trap,
> int __hash_page_huge(unsigned long ea, unsigned long access, unsigned long vsid,
> pte_t *ptep, unsigned long trap, unsigned long flags,
> int ssize, unsigned int shift, unsigned int mmu_psize);
> +
> +#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
> +u16 get_pte_pkey(struct mm_struct *mm, unsigned long address);
> +#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
> +
> #ifdef CONFIG_TRANSPARENT_HUGEPAGE
> extern int __hash_page_thp(unsigned long ea, unsigned long access,
> unsigned long vsid, pmd_t *pmdp, unsigned long trap,
> diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
> index 1e74529..591990c 100644
> --- a/arch/powerpc/mm/hash_utils_64.c
> +++ b/arch/powerpc/mm/hash_utils_64.c
> @@ -1573,6 +1573,34 @@ void hash_preload(struct mm_struct *mm, unsigned long ea,
> local_irq_restore(flags);
> }
>
> +#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
> +/*
> + * return the protection key associated with the given address
> + * and the mm_struct.
> + */
> +u16 get_pte_pkey(struct mm_struct *mm, unsigned long address)
> +{
> + pte_t *ptep;
> + u16 pkey = 0;
> + unsigned long flags;
> +
> + if (REGION_ID(address) == VMALLOC_REGION_ID)
> + mm = &init_mm;
IIUC, protection keys are only applicable for user space. This
function is getting used to populate siginfo structure. Then how
can we ever request this for any address in VMALLOC region.
> +
> + if (!mm || !mm->pgd)
> + return 0;
Is this really required at this stage ?
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
