mm/memblock.c: fix NULL dereference error

[cascardo/linux.git] / mm / mempolicy.c

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 36cc01b..d8c4e38 100644 (file)
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -97,7 +97,6 @@
 
 #include <asm/tlbflush.h>
 #include <asm/uaccess.h>
-#include <linux/random.h>
 
 #include "internal.h"
 
@@ -347,9 +346,7 @@ static void mpol_rebind_nodemask(struct mempolicy *pol, const nodemask_t *nodes,
                BUG();
 
        if (!node_isset(current->il_next, tmp)) {
-               current->il_next = next_node(current->il_next, tmp);
-               if (current->il_next >= MAX_NUMNODES)
-                       current->il_next = first_node(tmp);
+               current->il_next = next_node_in(current->il_next, tmp);
                if (current->il_next >= MAX_NUMNODES)
                        current->il_next = numa_node_id();
        }
@@ -515,6 +512,8 @@ static int queue_pages_pte_range(pmd_t *pmd, unsigned long addr,
                }
        }
 
+       if (pmd_trans_unstable(pmd))
+               return 0;
 retry:
        pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
        for (; addr != end; pte++, addr += PAGE_SIZE) {
@@ -532,7 +531,7 @@ retry:
                nid = page_to_nid(page);
                if (node_isset(nid, *qp->nmask) == !!(flags & MPOL_MF_INVERT))
                        continue;
-               if (PageTransCompound(page) && PageAnon(page)) {
+               if (PageTransCompound(page)) {
                        get_page(page);
                        pte_unmap_unlock(pte, ptl);
                        lock_page(page);
@@ -963,7 +962,7 @@ static void migrate_page_add(struct page *page, struct list_head *pagelist,
        if ((flags & MPOL_MF_MOVE_ALL) || page_mapcount(page) == 1) {
                if (!isolate_lru_page(page)) {
                        list_add_tail(&page->lru, pagelist);
-                       inc_zone_page_state(page, NR_ISOLATED_ANON +
+                       inc_node_page_state(page, NR_ISOLATED_ANON +
                                            page_is_file_cache(page));
                }
        }
@@ -1709,9 +1708,7 @@ static unsigned interleave_nodes(struct mempolicy *policy)
        struct task_struct *me = current;
 
        nid = me->il_next;
-       next = next_node(nid, policy->v.nodes);
-       if (next >= MAX_NUMNODES)
-               next = first_node(policy->v.nodes);
+       next = next_node_in(nid, policy->v.nodes);
        if (next < MAX_NUMNODES)
                me->il_next = next;
        return nid;
@@ -1744,18 +1741,18 @@ unsigned int mempolicy_slab_node(void)
                return interleave_nodes(policy);
 
        case MPOL_BIND: {
+               struct zoneref *z;
+
                /*
                 * Follow bind policy behavior and start allocation at the
                 * first node.
                 */
                struct zonelist *zonelist;
-               struct zone *zone;
                enum zone_type highest_zoneidx = gfp_zone(GFP_KERNEL);
                zonelist = &NODE_DATA(node)->node_zonelists[0];
-               (void)first_zones_zonelist(zonelist, highest_zoneidx,
-                                                       &policy->v.nodes,
-                                                       &zone);
-               return zone ? zone->node : node;
+               z = first_zones_zonelist(zonelist, highest_zoneidx,
+                                                       &policy->v.nodes);
+               return z->zone ? z->zone->node : node;
        }
 
        default:
@@ -1763,23 +1760,25 @@ unsigned int mempolicy_slab_node(void)
        }
 }
 
-/* Do static interleaving for a VMA with known offset. */
+/*
+ * Do static interleaving for a VMA with known offset @n.  Returns the n'th
+ * node in pol->v.nodes (starting from n=0), wrapping around if n exceeds the
+ * number of present nodes.
+ */
 static unsigned offset_il_node(struct mempolicy *pol,
-               struct vm_area_struct *vma, unsigned long off)
+                              struct vm_area_struct *vma, unsigned long n)
 {
        unsigned nnodes = nodes_weight(pol->v.nodes);
        unsigned target;
-       int c;
-       int nid = NUMA_NO_NODE;
+       int i;
+       int nid;
 
        if (!nnodes)
                return numa_node_id();
-       target = (unsigned int)off % nnodes;
-       c = 0;
-       do {
+       target = (unsigned int)n % nnodes;
+       nid = first_node(pol->v.nodes);
+       for (i = 0; i < target; i++)
                nid = next_node(nid, pol->v.nodes);
-               c++;
-       } while (c <= target);
        return nid;
 }
 
@@ -1805,21 +1804,6 @@ static inline unsigned interleave_nid(struct mempolicy *pol,
                return interleave_nodes(pol);
 }
 
-/*
- * Return the bit number of a random bit set in the nodemask.
- * (returns NUMA_NO_NODE if nodemask is empty)
- */
-int node_random(const nodemask_t *maskp)
-{
-       int w, bit = NUMA_NO_NODE;
-
-       w = nodes_weight(*maskp);
-       if (w)
-               bit = bitmap_ord_to_pos(maskp->bits,
-                       get_random_int() % w, MAX_NUMNODES);
-       return bit;
-}
-
 #ifdef CONFIG_HUGETLBFS
 /*
  * huge_zonelist(@vma, @addr, @gfp_flags, @mpol)
@@ -2284,7 +2268,7 @@ static void sp_free(struct sp_node *n)
 int mpol_misplaced(struct page *page, struct vm_area_struct *vma, unsigned long addr)
 {
        struct mempolicy *pol;
-       struct zone *zone;
+       struct zoneref *z;
        int curnid = page_to_nid(page);
        unsigned long pgoff;
        int thiscpu = raw_smp_processor_id();
@@ -2316,6 +2300,7 @@ int mpol_misplaced(struct page *page, struct vm_area_struct *vma, unsigned long
                break;
 
        case MPOL_BIND:
+
                /*
                 * allows binding to multiple nodes.
                 * use current page if in policy nodemask,
@@ -2324,11 +2309,11 @@ int mpol_misplaced(struct page *page, struct vm_area_struct *vma, unsigned long
                 */
                if (node_isset(curnid, pol->v.nodes))
                        goto out;
-               (void)first_zones_zonelist(
+               z = first_zones_zonelist(
                                node_zonelist(numa_node_id(), GFP_HIGHUSER),
                                gfp_zone(GFP_HIGHUSER),
-                               &pol->v.nodes, &zone);
-               polnid = zone->node;
+                               &pol->v.nodes);
+               polnid = z->zone->node;
                break;
 
        default: