diff options
Diffstat (limited to 'kernel/fork.c')
| -rw-r--r-- | kernel/fork.c | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/kernel/fork.c b/kernel/fork.c index d2da065442af..273364207f17 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -585,6 +585,7 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm, int retval; unsigned long charge; LIST_HEAD(uf); + MA_STATE(mas, &mm->mm_mt, 0, 0); uprobe_start_dup_mmap(); if (mmap_write_lock_killable(oldmm)) { @@ -614,6 +615,10 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm, goto out; khugepaged_fork(mm, oldmm); + retval = mas_expected_entries(&mas, oldmm->map_count); + if (retval) + goto out; + prev = NULL; for (mpnt = oldmm->mmap; mpnt; mpnt = mpnt->vm_next) { struct file *file; @@ -629,7 +634,7 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm, */ if (fatal_signal_pending(current)) { retval = -EINTR; - goto out; + goto loop_out; } if (mpnt->vm_flags & VM_ACCOUNT) { unsigned long len = vma_pages(mpnt); @@ -694,6 +699,11 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm, rb_link = &tmp->vm_rb.rb_right; rb_parent = &tmp->vm_rb; + /* Link the vma into the MT */ + mas.index = tmp->vm_start; + mas.last = tmp->vm_end - 1; + mas_store(&mas, tmp); + mm->map_count++; if (!(tmp->vm_flags & VM_WIPEONFORK)) retval = copy_page_range(tmp, mpnt); @@ -702,10 +712,12 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm, tmp->vm_ops->open(tmp); if (retval) - goto out; + goto loop_out; } /* a new mm has just been created */ retval = arch_dup_mmap(oldmm, mm); +loop_out: + mas_destroy(&mas); out: mmap_write_unlock(mm); flush_tlb_mm(oldmm); @@ -721,7 +733,7 @@ fail_nomem_policy: fail_nomem: retval = -ENOMEM; vm_unacct_memory(charge); - goto out; + goto loop_out; } static inline int mm_alloc_pgd(struct mm_struct *mm) @@ -1111,6 +1123,8 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p, { mm->mmap = NULL; mm->mm_rb = RB_ROOT; + mt_init_flags(&mm->mm_mt, MM_MT_FLAGS); + mt_set_external_lock(&mm->mm_mt, &mm->mmap_lock); mm->vmacache_seqnum = 0; atomic_set(&mm->mm_users, 1); atomic_set(&mm->mm_count, 1); |