diff options
Diffstat (limited to 'arch/powerpc/mm/subpage-prot.c')
| -rw-r--r-- | arch/powerpc/mm/subpage-prot.c | 28 |
1 files changed, 21 insertions, 7 deletions
diff --git a/arch/powerpc/mm/subpage-prot.c b/arch/powerpc/mm/subpage-prot.c index c72252542210..c9dff4e1f295 100644 --- a/arch/powerpc/mm/subpage-prot.c +++ b/arch/powerpc/mm/subpage-prot.c @@ -29,6 +29,9 @@ void subpage_prot_free(struct mm_struct *mm) unsigned long i, j, addr; u32 **p; + if (!spt) + return; + for (i = 0; i < 4; ++i) { if (spt->low_prot[i]) { free_page((unsigned long)spt->low_prot[i]); @@ -48,13 +51,7 @@ void subpage_prot_free(struct mm_struct *mm) free_page((unsigned long)p); } spt->maxaddr = 0; -} - -void subpage_prot_init_new_context(struct mm_struct *mm) -{ - struct subpage_prot_table *spt = mm_ctx_subpage_prot(&mm->context); - - memset(spt, 0, sizeof(*spt)); + kfree(spt); } static void hpte_flush_range(struct mm_struct *mm, unsigned long addr, @@ -99,6 +96,9 @@ static void subpage_prot_clear(unsigned long addr, unsigned long len) size_t nw; unsigned long next, limit; + if (!spt) + return ; + down_write(&mm->mmap_sem); limit = addr + len; if (limit > spt->maxaddr) @@ -218,6 +218,20 @@ SYSCALL_DEFINE3(subpage_prot, unsigned long, addr, return -EFAULT; down_write(&mm->mmap_sem); + + if (!spt) { + /* + * Allocate subpage prot table if not already done. + * Do this with mmap_sem held + */ + spt = kzalloc(sizeof(struct subpage_prot_table), GFP_KERNEL); + if (!spt) { + err = -ENOMEM; + goto out; + } + mm->context.hash_context->spt = spt; + } + subpage_mark_vma_nohuge(mm, addr, len); for (limit = addr + len; addr < limit; addr = next) { next = pmd_addr_end(addr, limit); |