diff options
Diffstat (limited to 'arch/powerpc/mm/subpage-prot.c')
| -rw-r--r-- | arch/powerpc/mm/subpage-prot.c | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/arch/powerpc/mm/subpage-prot.c b/arch/powerpc/mm/subpage-prot.c index 7c415ddde948..aa74acb0fdfc 100644 --- a/arch/powerpc/mm/subpage-prot.c +++ b/arch/powerpc/mm/subpage-prot.c @@ -130,6 +130,53 @@ static void subpage_prot_clear(unsigned long addr, unsigned long len) up_write(&mm->mmap_sem); } +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +static int subpage_walk_pmd_entry(pmd_t *pmd, unsigned long addr, + unsigned long end, struct mm_walk *walk) +{ + struct vm_area_struct *vma = walk->private; + split_huge_page_pmd(vma, addr, pmd); + return 0; +} + +static void subpage_mark_vma_nohuge(struct mm_struct *mm, unsigned long addr, + unsigned long len) +{ + struct vm_area_struct *vma; + struct mm_walk subpage_proto_walk = { + .mm = mm, + .pmd_entry = subpage_walk_pmd_entry, + }; + + /* + * We don't try too hard, we just mark all the vma in that range + * VM_NOHUGEPAGE and split them. + */ + vma = find_vma(mm, addr); + /* + * If the range is in unmapped range, just return + */ + if (vma && ((addr + len) <= vma->vm_start)) + return; + + while (vma) { + if (vma->vm_start >= (addr + len)) + break; + vma->vm_flags |= VM_NOHUGEPAGE; + subpage_proto_walk.private = vma; + walk_page_range(vma->vm_start, vma->vm_end, + &subpage_proto_walk); + vma = vma->vm_next; + } +} +#else +static void subpage_mark_vma_nohuge(struct mm_struct *mm, unsigned long addr, + unsigned long len) +{ + return; +} +#endif + /* * Copy in a subpage protection map for an address range. * The map has 2 bits per 4k subpage, so 32 bits per 64k page. @@ -168,6 +215,7 @@ long sys_subpage_prot(unsigned long addr, unsigned long len, u32 __user *map) return -EFAULT; down_write(&mm->mmap_sem); + subpage_mark_vma_nohuge(mm, addr, len); for (limit = addr + len; addr < limit; addr = next) { next = pmd_addr_end(addr, limit); err = -ENOMEM; |