diff options
Diffstat (limited to 'arch/powerpc/mm/book3s64/hash_utils.c')
| -rw-r--r-- | arch/powerpc/mm/book3s64/hash_utils.c | 39 |
1 files changed, 22 insertions, 17 deletions
diff --git a/arch/powerpc/mm/book3s64/hash_utils.c b/arch/powerpc/mm/book3s64/hash_utils.c index 985cabdd7f67..fc92613dc2bf 100644 --- a/arch/powerpc/mm/book3s64/hash_utils.c +++ b/arch/powerpc/mm/book3s64/hash_utils.c @@ -37,6 +37,9 @@ #include <linux/cpu.h> #include <linux/pgtable.h> #include <linux/debugfs.h> +#include <linux/random.h> +#include <linux/elf-randomize.h> +#include <linux/of_fdt.h> #include <asm/interrupt.h> #include <asm/processor.h> @@ -46,7 +49,6 @@ #include <asm/types.h> #include <linux/uaccess.h> #include <asm/machdep.h> -#include <asm/prom.h> #include <asm/io.h> #include <asm/eeh.h> #include <asm/tlb.h> @@ -1264,7 +1266,6 @@ unsigned int hash_page_do_lazy_icache(unsigned int pp, pte_t pte, int trap) return pp; } -#ifdef CONFIG_PPC_MM_SLICES static unsigned int get_paca_psize(unsigned long addr) { unsigned char *psizes; @@ -1281,12 +1282,6 @@ static unsigned int get_paca_psize(unsigned long addr) return (psizes[index >> 1] >> (mask_index * 4)) & 0xF; } -#else -unsigned int get_paca_psize(unsigned long addr) -{ - return get_paca()->mm_ctx_user_psize; -} -#endif /* * Demote a segment to using 4k pages. @@ -1343,7 +1338,7 @@ static int subpage_protection(struct mm_struct *mm, unsigned long ea) spp >>= 30 - 2 * ((ea >> 12) & 0xf); /* - * 0 -> full premission + * 0 -> full permission * 1 -> Read only * 2 -> no access. * We return the flag that need to be cleared. @@ -1664,7 +1659,7 @@ DEFINE_INTERRUPT_HANDLER(do_hash_fault) err = hash_page_mm(mm, ea, access, TRAP(regs), flags); if (unlikely(err < 0)) { - // failed to instert a hash PTE due to an hypervisor error + // failed to insert a hash PTE due to an hypervisor error if (user_mode(regs)) { if (IS_ENABLED(CONFIG_PPC_SUBPAGE_PROT) && err == -2) _exception(SIGSEGV, regs, SEGV_ACCERR, ea); @@ -1680,7 +1675,6 @@ DEFINE_INTERRUPT_HANDLER(do_hash_fault) } } -#ifdef CONFIG_PPC_MM_SLICES static bool should_hash_preload(struct mm_struct *mm, unsigned long ea) { int psize = get_slice_psize(mm, ea); @@ -1697,12 +1691,6 @@ static bool should_hash_preload(struct mm_struct *mm, unsigned long ea) return true; } -#else -static bool should_hash_preload(struct mm_struct *mm, unsigned long ea) -{ - return true; -} -#endif static void hash_preload(struct mm_struct *mm, pte_t *ptep, unsigned long ea, bool is_exec, unsigned long trap) @@ -2147,3 +2135,20 @@ void __init print_system_hash_info(void) if (htab_hash_mask) pr_info("htab_hash_mask = 0x%lx\n", htab_hash_mask); } + +unsigned long arch_randomize_brk(struct mm_struct *mm) +{ + /* + * If we are using 1TB segments and we are allowed to randomise + * the heap, we can put it above 1TB so it is backed by a 1TB + * segment. Otherwise the heap will be in the bottom 1TB + * which always uses 256MB segments and this may result in a + * performance penalty. + */ + if (is_32bit_task()) + return randomize_page(mm->brk, SZ_32M); + else if (!radix_enabled() && mmu_highuser_ssize == MMU_SEGSIZE_1T) + return randomize_page(max_t(unsigned long, mm->brk, SZ_1T), SZ_1G); + else + return randomize_page(mm->brk, SZ_1G); +} |