mm/mempolicy: Use maple tree iterators instead of vma linked list

Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index b5f4f584009b0a107b04b4ec904f94f916dd79a6..b7b9c224334e0c4a4fd024957f2f3277b667b511 100644 (file)
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -379,10 +379,13 @@ void mpol_rebind_task(struct task_struct *tsk, const nodemask_t *new)
 void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new)
 {
        struct vm_area_struct *vma;
+       MA_STATE(mas, &mm->mm_mt, 0, 0);
 
        mmap_write_lock(mm);
-       for (vma = mm->mmap; vma; vma = vma->vm_next)
+       mas_lock(&mas);
+       mas_for_each(&mas, vma, ULONG_MAX)
                mpol_rebind_policy(vma->vm_policy, new);
+       mas_unlock(&mas);
        mmap_write_unlock(mm);
 }
 
@@ -649,7 +652,7 @@ static unsigned long change_prot_numa(struct vm_area_struct *vma,
 static int queue_pages_test_walk(unsigned long start, unsigned long end,
                                struct mm_walk *walk)
 {
-       struct vm_area_struct *vma = walk->vma;
+       struct vm_area_struct *next, *vma = walk->vma;
        struct queue_pages *qp = walk->private;
        unsigned long endvma = vma->vm_end;
        unsigned long flags = qp->flags;
@@ -664,9 +667,10 @@ static int queue_pages_test_walk(unsigned long start, unsigned long end,
                        /* hole at head side of range */
                        return -EFAULT;
        }
+       next = vma_next(vma->vm_mm, vma);
        if (!(flags & MPOL_MF_DISCONTIG_OK) &&
                ((vma->vm_end < qp->end) &&
-               (!vma->vm_next || vma->vm_end < vma->vm_next->vm_start)))
+               (!next || vma->vm_end < next->vm_start)))
                /* hole at middle or tail of range */
                return -EFAULT;
 
@@ -780,28 +784,28 @@ static int vma_replace_policy(struct vm_area_struct *vma,
 static int mbind_range(struct mm_struct *mm, unsigned long start,
                       unsigned long end, struct mempolicy *new_pol)
 {
-       struct vm_area_struct *next;
        struct vm_area_struct *prev;
        struct vm_area_struct *vma;
        int err = 0;
        pgoff_t pgoff;
        unsigned long vmstart;
        unsigned long vmend;
+       MA_STATE(mas, &mm->mm_mt, start, start);
 
-       vma = find_vma(mm, start);
+       rcu_read_lock();
+       vma = mas_find(&mas, ULONG_MAX);
        VM_BUG_ON(!vma);
 
-       prev = vma->vm_prev;
+       prev = mas_prev(&mas, 0);
        if (start > vma->vm_start)
                prev = vma;
 
-       for (; vma && vma->vm_start < end; prev = vma, vma = next) {
-               next = vma->vm_next;
+       mas_for_each(&mas, vma, end - 1) {
                vmstart = max(start, vma->vm_start);
                vmend   = min(end, vma->vm_end);
 
                if (mpol_equal(vma_policy(vma), new_pol))
-                       continue;
+                       goto next;
 
                pgoff = vma->vm_pgoff +
                        ((vmstart - vma->vm_start) >> PAGE_SHIFT);
@@ -810,7 +814,7 @@ static int mbind_range(struct mm_struct *mm, unsigned long start,
                                 new_pol, vma->vm_userfaultfd_ctx);
                if (prev) {
                        vma = prev;
-                       next = vma->vm_next;
+                       mas_set(&mas, vma->vm_end);
                        if (mpol_equal(vma_policy(vma), new_pol))
                                continue;
                        /* vma_merge() joined vma && vma->next, case 8 */
@@ -826,13 +830,16 @@ static int mbind_range(struct mm_struct *mm, unsigned long start,
                        if (err)
                                goto out;
                }
- replace:
+replace:
                err = vma_replace_policy(vma, new_pol);
                if (err)
                        goto out;
+next:
+               prev = vma;
        }
 
- out:
+out:
+       rcu_read_unlock();
        return err;
 }
 
@@ -1062,6 +1069,7 @@ static int migrate_to_node(struct mm_struct *mm, int source, int dest,
                           int flags)
 {
        nodemask_t nmask;
+       struct vm_area_struct *vma;
        LIST_HEAD(pagelist);
        int err = 0;
        struct migration_target_control mtc = {
@@ -1077,8 +1085,9 @@ static int migrate_to_node(struct mm_struct *mm, int source, int dest,
         * need migration.  Between passing in the full user address
         * space range and MPOL_MF_DISCONTIG_OK, this call can not fail.
         */
+       vma = find_vma(mm, 0);
        VM_BUG_ON(!(flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)));
-       queue_pages_range(mm, mm->mmap->vm_start, mm->task_size, &nmask,
+       queue_pages_range(mm, vma->vm_start, mm->task_size, &nmask,
                        flags | MPOL_MF_DISCONTIG_OK, &pagelist);
 
        if (!list_empty(&pagelist)) {
@@ -1207,14 +1216,15 @@ static struct page *new_page(struct page *page, unsigned long start)
 {
        struct vm_area_struct *vma;
        unsigned long address;
+       MA_STATE(mas, &current->mm->mm_mt, start, start);
 
-       vma = find_vma(current->mm, start);
-       while (vma) {
+       rcu_read_lock();
+       mas_for_each(&mas, vma, ULONG_MAX) {
                address = page_address_in_vma(page, vma);
                if (address != -EFAULT)
                        break;
-               vma = vma->vm_next;
        }
+       rcu_read_unlock();
 
        if (PageHuge(page)) {
                return alloc_huge_page_vma(page_hstate(compound_head(page)),