mempolicy: use MPOL_F_LOCAL to Indicate Preferred Local Policy

[pandora-kernel.git] / mm / mempolicy.c

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 6c7ba1a..143b019 100644 (file)
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -63,7 +63,6 @@
    grows down?
    make bind policy root only? It can trigger oom much faster and the
    kernel is not always grateful with that.
    grows down?
    make bind policy root only? It can trigger oom much faster and the
    kernel is not always grateful with that.

-   could replace all the switch()es with a mempolicy_ops structure.

 */
 
 #include <linux/mempolicy.h>
 */
 
 #include <linux/mempolicy.h>


@@ -105,142 +104,264 @@ static struct kmem_cache *sn_cache;
    policied. */
 enum zone_type policy_zone = 0;
 
    policied. */
 enum zone_type policy_zone = 0;
 

+/*
+ * run-time system-wide default policy => local allocation
+ */

 struct mempolicy default_policy = {
        .refcnt = ATOMIC_INIT(1), /* never free it */
 struct mempolicy default_policy = {
        .refcnt = ATOMIC_INIT(1), /* never free it */

-       .policy = MPOL_DEFAULT,
+       .mode = MPOL_PREFERRED,
+       .flags = MPOL_F_LOCAL,

 };
 
 };
 

-static void mpol_rebind_policy(struct mempolicy *pol,
-                               const nodemask_t *newmask);
+static const struct mempolicy_operations {
+       int (*create)(struct mempolicy *pol, const nodemask_t *nodes);
+       void (*rebind)(struct mempolicy *pol, const nodemask_t *nodes);
+} mpol_ops[MPOL_MAX];

 
 

-/* Do sanity checking on a policy */
-static int mpol_check_policy(int mode, nodemask_t *nodes)
+/* Check that the nodemask contains at least one populated zone */
+static int is_valid_nodemask(const nodemask_t *nodemask)

 {
 {

-       int was_empty, is_empty;
+       int nd, k;

 
 

-       if (!nodes)
-               return 0;
+       /* Check that there is something useful in this mask */
+       k = policy_zone;

 
 

-       /*
-        * "Contextualize" the in-coming nodemast for cpusets:
-        * Remember whether in-coming nodemask was empty,  If not,
-        * restrict the nodes to the allowed nodes in the cpuset.
-        * This is guaranteed to be a subset of nodes with memory.
-        */
-       cpuset_update_task_memory_state();
-       is_empty = was_empty = nodes_empty(*nodes);
-       if (!was_empty) {
-               nodes_and(*nodes, *nodes, cpuset_current_mems_allowed);
-               is_empty = nodes_empty(*nodes); /* after "contextualization" */
-       }
+       for_each_node_mask(nd, *nodemask) {
+               struct zone *z;

 
 

-       switch (mode) {
-       case MPOL_DEFAULT:
-               /*
-                * require caller to specify an empty nodemask
-                * before "contextualization"
-                */
-               if (!was_empty)
-                       return -EINVAL;
-               break;
-       case MPOL_BIND:
-       case MPOL_INTERLEAVE:
-               /*
-                * require at least 1 valid node after "contextualization"
-                */
-               if (is_empty)
-                       return -EINVAL;
-               break;
-       case MPOL_PREFERRED:
-               /*
-                * Did caller specify invalid nodes?
-                * Don't silently accept this as "local allocation".
-                */
-               if (!was_empty && is_empty)
-                       return -EINVAL;
-               break;
+               for (k = 0; k <= policy_zone; k++) {
+                       z = &NODE_DATA(nd)->node_zones[k];
+                       if (z->present_pages > 0)
+                               return 1;
+               }

        }
        }

+

        return 0;
 }
 
        return 0;
 }
 

-/* Generate a custom zonelist for the BIND policy. */
-static struct zonelist *bind_zonelist(nodemask_t *nodes)
+static inline int mpol_store_user_nodemask(const struct mempolicy *pol)

 {
 {

-       struct zonelist *zl;
-       int num, max, nd;
-       enum zone_type k;
+       return pol->flags & (MPOL_F_STATIC_NODES | MPOL_F_RELATIVE_NODES);
+}

 
 

-       max = 1 + MAX_NR_ZONES * nodes_weight(*nodes);
-       max++;                  /* space for zlcache_ptr (see mmzone.h) */
-       zl = kmalloc(sizeof(struct zone *) * max, GFP_KERNEL);
-       if (!zl)
-               return ERR_PTR(-ENOMEM);
-       zl->zlcache_ptr = NULL;
-       num = 0;
-       /* First put in the highest zones from all nodes, then all the next 
-          lower zones etc. Avoid empty zones because the memory allocator
-          doesn't like them. If you implement node hot removal you
-          have to fix that. */
-       k = MAX_NR_ZONES - 1;
-       while (1) {
-               for_each_node_mask(nd, *nodes) { 
-                       struct zone *z = &NODE_DATA(nd)->node_zones[k];
-                       if (z->present_pages > 0) 
-                               zl->zones[num++] = z;
-               }
-               if (k == 0)
-                       break;
-               k--;
-       }
-       if (num == 0) {
-               kfree(zl);
-               return ERR_PTR(-EINVAL);
-       }
-       zl->zones[num] = NULL;
-       return zl;
+static void mpol_relative_nodemask(nodemask_t *ret, const nodemask_t *orig,
+                                  const nodemask_t *rel)
+{
+       nodemask_t tmp;
+       nodes_fold(tmp, *orig, nodes_weight(*rel));
+       nodes_onto(*ret, tmp, *rel);
+}
+
+static int mpol_new_interleave(struct mempolicy *pol, const nodemask_t *nodes)
+{
+       if (nodes_empty(*nodes))
+               return -EINVAL;
+       pol->v.nodes = *nodes;
+       return 0;
+}
+
+static int mpol_new_preferred(struct mempolicy *pol, const nodemask_t *nodes)
+{
+       if (!nodes)
+               pol->flags |= MPOL_F_LOCAL;     /* local allocation */
+       else if (nodes_empty(*nodes))
+               return -EINVAL;                 /*  no allowed nodes */
+       else
+               pol->v.preferred_node = first_node(*nodes);
+       return 0;
+}
+
+static int mpol_new_bind(struct mempolicy *pol, const nodemask_t *nodes)
+{
+       if (!is_valid_nodemask(nodes))
+               return -EINVAL;
+       pol->v.nodes = *nodes;
+       return 0;

 }
 
 /* Create a new policy */
 }
 
 /* Create a new policy */

-static struct mempolicy *mpol_new(int mode, nodemask_t *nodes)
+static struct mempolicy *mpol_new(unsigned short mode, unsigned short flags,
+                                 nodemask_t *nodes)

 {
        struct mempolicy *policy;
 {
        struct mempolicy *policy;

+       nodemask_t cpuset_context_nmask;
+       int ret;

 
 

-       pr_debug("setting mode %d nodes[0] %lx\n",
-                mode, nodes ? nodes_addr(*nodes)[0] : -1);
+       pr_debug("setting mode %d flags %d nodes[0] %lx\n",
+                mode, flags, nodes ? nodes_addr(*nodes)[0] : -1);

 
 

-       if (mode == MPOL_DEFAULT)
-               return NULL;
+       if (mode == MPOL_DEFAULT) {
+               if (nodes && !nodes_empty(*nodes))
+                       return ERR_PTR(-EINVAL);
+               return NULL;    /* simply delete any existing policy */
+       }
+       VM_BUG_ON(!nodes);
+
+       /*
+        * MPOL_PREFERRED cannot be used with MPOL_F_STATIC_NODES or
+        * MPOL_F_RELATIVE_NODES if the nodemask is empty (local allocation).
+        * All other modes require a valid pointer to a non-empty nodemask.
+        */
+       if (mode == MPOL_PREFERRED) {
+               if (nodes_empty(*nodes)) {
+                       if (((flags & MPOL_F_STATIC_NODES) ||
+                            (flags & MPOL_F_RELATIVE_NODES)))
+                               return ERR_PTR(-EINVAL);
+                       nodes = NULL;   /* flag local alloc */
+               }
+       } else if (nodes_empty(*nodes))
+               return ERR_PTR(-EINVAL);

        policy = kmem_cache_alloc(policy_cache, GFP_KERNEL);
        if (!policy)
                return ERR_PTR(-ENOMEM);
        atomic_set(&policy->refcnt, 1);
        policy = kmem_cache_alloc(policy_cache, GFP_KERNEL);
        if (!policy)
                return ERR_PTR(-ENOMEM);
        atomic_set(&policy->refcnt, 1);

-       switch (mode) {
-       case MPOL_INTERLEAVE:
-               policy->v.nodes = *nodes;
-               if (nodes_weight(policy->v.nodes) == 0) {
-                       kmem_cache_free(policy_cache, policy);
-                       return ERR_PTR(-EINVAL);
-               }
-               break;
-       case MPOL_PREFERRED:
-               policy->v.preferred_node = first_node(*nodes);
-               if (policy->v.preferred_node >= MAX_NUMNODES)
-                       policy->v.preferred_node = -1;
-               break;
-       case MPOL_BIND:
-               policy->v.zonelist = bind_zonelist(nodes);
-               if (IS_ERR(policy->v.zonelist)) {
-                       void *error_code = policy->v.zonelist;
-                       kmem_cache_free(policy_cache, policy);
-                       return error_code;
-               }
-               break;
+       policy->mode = mode;
+       policy->flags = flags;
+
+       if (nodes) {
+               /*
+                * cpuset related setup doesn't apply to local allocation
+                */
+               cpuset_update_task_memory_state();
+               if (flags & MPOL_F_RELATIVE_NODES)
+                       mpol_relative_nodemask(&cpuset_context_nmask, nodes,
+                                              &cpuset_current_mems_allowed);
+               else
+                       nodes_and(cpuset_context_nmask, *nodes,
+                                 cpuset_current_mems_allowed);
+               if (mpol_store_user_nodemask(policy))
+                       policy->w.user_nodemask = *nodes;
+               else
+                       policy->w.cpuset_mems_allowed =
+                                               cpuset_mems_allowed(current);
+       }
+
+       ret = mpol_ops[mode].create(policy,
+                               nodes ? &cpuset_context_nmask : NULL);
+       if (ret < 0) {
+               kmem_cache_free(policy_cache, policy);
+               return ERR_PTR(ret);

        }
        }

-       policy->policy = mode;
-       policy->cpuset_mems_allowed = cpuset_mems_allowed(current);

        return policy;
 }
 
        return policy;
 }
 

+/* Slow path of a mpol destructor. */
+void __mpol_put(struct mempolicy *p)
+{
+       if (!atomic_dec_and_test(&p->refcnt))
+               return;
+       kmem_cache_free(policy_cache, p);
+}
+
+static void mpol_rebind_default(struct mempolicy *pol, const nodemask_t *nodes)
+{
+}
+
+static void mpol_rebind_nodemask(struct mempolicy *pol,
+                                const nodemask_t *nodes)
+{
+       nodemask_t tmp;
+
+       if (pol->flags & MPOL_F_STATIC_NODES)
+               nodes_and(tmp, pol->w.user_nodemask, *nodes);
+       else if (pol->flags & MPOL_F_RELATIVE_NODES)
+               mpol_relative_nodemask(&tmp, &pol->w.user_nodemask, nodes);
+       else {
+               nodes_remap(tmp, pol->v.nodes, pol->w.cpuset_mems_allowed,
+                           *nodes);
+               pol->w.cpuset_mems_allowed = *nodes;
+       }
+
+       pol->v.nodes = tmp;
+       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);
+               if (current->il_next >= MAX_NUMNODES)
+                       current->il_next = numa_node_id();
+       }
+}
+
+static void mpol_rebind_preferred(struct mempolicy *pol,
+                                 const nodemask_t *nodes)
+{
+       nodemask_t tmp;
+
+       if (pol->flags & MPOL_F_STATIC_NODES) {
+               int node = first_node(pol->w.user_nodemask);
+
+               if (node_isset(node, *nodes)) {
+                       pol->v.preferred_node = node;
+                       pol->flags &= ~MPOL_F_LOCAL;
+               } else
+                       pol->flags |= MPOL_F_LOCAL;
+       } else if (pol->flags & MPOL_F_RELATIVE_NODES) {
+               mpol_relative_nodemask(&tmp, &pol->w.user_nodemask, nodes);
+               pol->v.preferred_node = first_node(tmp);
+       } else if (!(pol->flags & MPOL_F_LOCAL)) {
+               pol->v.preferred_node = node_remap(pol->v.preferred_node,
+                                                  pol->w.cpuset_mems_allowed,
+                                                  *nodes);
+               pol->w.cpuset_mems_allowed = *nodes;
+       }
+}
+
+/* Migrate a policy to a different set of nodes */
+static void mpol_rebind_policy(struct mempolicy *pol,
+                              const nodemask_t *newmask)
+{
+       if (!pol)
+               return;
+       if (!mpol_store_user_nodemask(pol) &&
+           nodes_equal(pol->w.cpuset_mems_allowed, *newmask))
+               return;
+       mpol_ops[pol->mode].rebind(pol, newmask);
+}
+
+/*
+ * Wrapper for mpol_rebind_policy() that just requires task
+ * pointer, and updates task mempolicy.
+ */
+
+void mpol_rebind_task(struct task_struct *tsk, const nodemask_t *new)
+{
+       mpol_rebind_policy(tsk->mempolicy, new);
+}
+
+/*
+ * Rebind each vma in mm to new nodemask.
+ *
+ * Call holding a reference to mm.  Takes mm->mmap_sem during call.
+ */
+
+void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new)
+{
+       struct vm_area_struct *vma;
+
+       down_write(&mm->mmap_sem);
+       for (vma = mm->mmap; vma; vma = vma->vm_next)
+               mpol_rebind_policy(vma->vm_policy, new);
+       up_write(&mm->mmap_sem);
+}
+
+static const struct mempolicy_operations mpol_ops[MPOL_MAX] = {
+       [MPOL_DEFAULT] = {
+               .rebind = mpol_rebind_default,
+       },
+       [MPOL_INTERLEAVE] = {
+               .create = mpol_new_interleave,
+               .rebind = mpol_rebind_nodemask,
+       },
+       [MPOL_PREFERRED] = {
+               .create = mpol_new_preferred,
+               .rebind = mpol_rebind_preferred,
+       },
+       [MPOL_BIND] = {
+               .create = mpol_new_bind,
+               .rebind = mpol_rebind_nodemask,
+       },
+};
+

 static void gather_stats(struct page *, void *, int pte_dirty);
 static void migrate_page_add(struct page *page, struct list_head *pagelist,
                                unsigned long flags);
 static void gather_stats(struct page *, void *, int pte_dirty);
 static void migrate_page_add(struct page *page, struct list_head *pagelist,
                                unsigned long flags);


@@ -421,7 +542,7 @@ static int policy_vma(struct vm_area_struct *vma, struct mempolicy *new)
        if (!err) {
                mpol_get(new);
                vma->vm_policy = new;
        if (!err) {
                mpol_get(new);
                vma->vm_policy = new;

-               mpol_free(old);
+               mpol_put(old);

        }
        return err;
 }
        }
        return err;
 }


@@ -479,46 +600,55 @@ static void mpol_set_task_struct_flag(void)
 }
 
 /* Set the process memory policy */
 }
 
 /* Set the process memory policy */

-static long do_set_mempolicy(int mode, nodemask_t *nodes)
+static long do_set_mempolicy(unsigned short mode, unsigned short flags,
+                            nodemask_t *nodes)

 {
        struct mempolicy *new;
 {
        struct mempolicy *new;

+       struct mm_struct *mm = current->mm;

 
 

-       if (mpol_check_policy(mode, nodes))
-               return -EINVAL;
-       new = mpol_new(mode, nodes);
+       new = mpol_new(mode, flags, nodes);

        if (IS_ERR(new))
                return PTR_ERR(new);
        if (IS_ERR(new))
                return PTR_ERR(new);

-       mpol_free(current->mempolicy);
+
+       /*
+        * prevent changing our mempolicy while show_numa_maps()
+        * is using it.
+        * Note:  do_set_mempolicy() can be called at init time
+        * with no 'mm'.
+        */
+       if (mm)
+               down_write(&mm->mmap_sem);
+       mpol_put(current->mempolicy);

        current->mempolicy = new;
        mpol_set_task_struct_flag();
        current->mempolicy = new;
        mpol_set_task_struct_flag();

-       if (new && new->policy == MPOL_INTERLEAVE)
+       if (new && new->mode == MPOL_INTERLEAVE &&
+           nodes_weight(new->v.nodes))

                current->il_next = first_node(new->v.nodes);
                current->il_next = first_node(new->v.nodes);

+       if (mm)
+               up_write(&mm->mmap_sem);
+

        return 0;
 }
 
        return 0;
 }
 

-/* Fill a zone bitmap for a policy */
-static void get_zonemask(struct mempolicy *p, nodemask_t *nodes)
+/*
+ * Return nodemask for policy for get_mempolicy() query
+ */
+static void get_policy_nodemask(struct mempolicy *p, nodemask_t *nodes)

 {
 {

-       int i;
-

        nodes_clear(*nodes);
        nodes_clear(*nodes);

-       switch (p->policy) {
+       if (p == &default_policy)
+               return;
+
+       switch (p->mode) {

        case MPOL_BIND:
        case MPOL_BIND:

-               for (i = 0; p->v.zonelist->zones[i]; i++)
-                       node_set(zone_to_nid(p->v.zonelist->zones[i]),
-                               *nodes);
-               break;
-       case MPOL_DEFAULT:
-               break;
+               /* Fall through */

        case MPOL_INTERLEAVE:
                *nodes = p->v.nodes;
                break;
        case MPOL_PREFERRED:
        case MPOL_INTERLEAVE:
                *nodes = p->v.nodes;
                break;
        case MPOL_PREFERRED:

-               /* or use current node instead of memory_map? */
-               if (p->v.preferred_node < 0)
-                       *nodes = node_states[N_HIGH_MEMORY];
-               else
+               if (!(p->flags & MPOL_F_LOCAL))

                        node_set(p->v.preferred_node, *nodes);
                        node_set(p->v.preferred_node, *nodes);

+               /* else return empty node mask for local allocation */

                break;
        default:
                BUG();
                break;
        default:
                BUG();


@@ -561,6 +691,11 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask,
        }
 
        if (flags & MPOL_F_ADDR) {
        }
 
        if (flags & MPOL_F_ADDR) {

+               /*
+                * Do NOT fall back to task policy if the
+                * vma/shared policy at addr is NULL.  We
+                * want to return MPOL_DEFAULT in this case.
+                */

                down_read(&mm->mmap_sem);
                vma = find_vma_intersection(mm, addr, addr+1);
                if (!vma) {
                down_read(&mm->mmap_sem);
                vma = find_vma_intersection(mm, addr, addr+1);
                if (!vma) {


@@ -575,7 +710,7 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask,
                return -EINVAL;
 
        if (!pol)
                return -EINVAL;
 
        if (!pol)

-               pol = &default_policy;
+               pol = &default_policy;  /* indicates default behavior */

 
        if (flags & MPOL_F_NODE) {
                if (flags & MPOL_F_ADDR) {
 
        if (flags & MPOL_F_NODE) {
                if (flags & MPOL_F_ADDR) {


@@ -584,14 +719,17 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask,
                                goto out;
                        *policy = err;
                } else if (pol == current->mempolicy &&
                                goto out;
                        *policy = err;
                } else if (pol == current->mempolicy &&

-                               pol->policy == MPOL_INTERLEAVE) {
+                               pol->mode == MPOL_INTERLEAVE) {

                        *policy = current->il_next;
                } else {
                        err = -EINVAL;
                        goto out;
                }
                        *policy = current->il_next;
                } else {
                        err = -EINVAL;
                        goto out;
                }

-       } else
-               *policy = pol->policy;
+       } else {
+               *policy = pol == &default_policy ? MPOL_DEFAULT :
+                                               pol->mode;
+               *policy |= pol->flags;
+       }

 
        if (vma) {
                up_read(&current->mm->mmap_sem);
 
        if (vma) {
                up_read(&current->mm->mmap_sem);


@@ -600,9 +738,10 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask,
 
        err = 0;
        if (nmask)
 
        err = 0;
        if (nmask)

-               get_zonemask(pol, nmask);
+               get_policy_nodemask(pol, nmask);

 
  out:
 
  out:

+       mpol_cond_put(pol);

        if (vma)
                up_read(&current->mm->mmap_sem);
        return err;
        if (vma)
                up_read(&current->mm->mmap_sem);
        return err;


@@ -664,7 +803,7 @@ int do_migrate_pages(struct mm_struct *mm,
        int err = 0;
        nodemask_t tmp;
 
        int err = 0;
        nodemask_t tmp;
 

-       down_read(&mm->mmap_sem);
+       down_read(&mm->mmap_sem);

 
        err = migrate_vmas(mm, from_nodes, to_nodes, flags);
        if (err)
 
        err = migrate_vmas(mm, from_nodes, to_nodes, flags);
        if (err)


@@ -781,8 +920,8 @@ static struct page *new_vma_page(struct page *page, unsigned long private, int *
 #endif
 
 static long do_mbind(unsigned long start, unsigned long len,
 #endif
 
 static long do_mbind(unsigned long start, unsigned long len,

-                    unsigned long mode, nodemask_t *nmask,
-                    unsigned long flags)
+                    unsigned short mode, unsigned short mode_flags,
+                    nodemask_t *nmask, unsigned long flags)

 {
        struct vm_area_struct *vma;
        struct mm_struct *mm = current->mm;
 {
        struct vm_area_struct *vma;
        struct mm_struct *mm = current->mm;


@@ -791,9 +930,8 @@ static long do_mbind(unsigned long start, unsigned long len,
        int err;
        LIST_HEAD(pagelist);
 
        int err;
        LIST_HEAD(pagelist);
 

-       if ((flags & ~(unsigned long)(MPOL_MF_STRICT |
-                                     MPOL_MF_MOVE | MPOL_MF_MOVE_ALL))
-           || mode > MPOL_MAX)
+       if (flags & ~(unsigned long)(MPOL_MF_STRICT |
+                                    MPOL_MF_MOVE | MPOL_MF_MOVE_ALL))

                return -EINVAL;
        if ((flags & MPOL_MF_MOVE_ALL) && !capable(CAP_SYS_NICE))
                return -EPERM;
                return -EINVAL;
        if ((flags & MPOL_MF_MOVE_ALL) && !capable(CAP_SYS_NICE))
                return -EPERM;


@@ -812,10 +950,7 @@ static long do_mbind(unsigned long start, unsigned long len,
        if (end == start)
                return 0;
 
        if (end == start)
                return 0;
 

-       if (mpol_check_policy(mode, nmask))
-               return -EINVAL;
-
-       new = mpol_new(mode, nmask);
+       new = mpol_new(mode, mode_flags, nmask);

        if (IS_ERR(new))
                return PTR_ERR(new);
 
        if (IS_ERR(new))
                return PTR_ERR(new);
 


@@ -826,8 +961,9 @@ static long do_mbind(unsigned long start, unsigned long len,
        if (!new)
                flags |= MPOL_MF_DISCONTIG_OK;
 
        if (!new)
                flags |= MPOL_MF_DISCONTIG_OK;
 

-       pr_debug("mbind %lx-%lx mode:%ld nodes:%lx\n",start,start+len,
-                mode, nmask ? nodes_addr(*nmask)[0] : -1);
+       pr_debug("mbind %lx-%lx mode:%d flags:%d nodes:%lx\n",
+                start, start + len, mode, mode_flags,
+                nmask ? nodes_addr(*nmask)[0] : -1);

 
        down_write(&mm->mmap_sem);
        vma = check_range(mm, start, end, nmask,
 
        down_write(&mm->mmap_sem);
        vma = check_range(mm, start, end, nmask,


@@ -848,7 +984,7 @@ static long do_mbind(unsigned long start, unsigned long len,
        }
 
        up_write(&mm->mmap_sem);
        }
 
        up_write(&mm->mmap_sem);

-       mpol_free(new);
+       mpol_put(new);

        return err;
 }
 
        return err;
 }
 


@@ -926,11 +1062,19 @@ asmlinkage long sys_mbind(unsigned long start, unsigned long len,
 {
        nodemask_t nodes;
        int err;
 {
        nodemask_t nodes;
        int err;

+       unsigned short mode_flags;

 
 

+       mode_flags = mode & MPOL_MODE_FLAGS;
+       mode &= ~MPOL_MODE_FLAGS;
+       if (mode >= MPOL_MAX)
+               return -EINVAL;
+       if ((mode_flags & MPOL_F_STATIC_NODES) &&
+           (mode_flags & MPOL_F_RELATIVE_NODES))
+               return -EINVAL;

        err = get_nodes(&nodes, nmask, maxnode);
        if (err)
                return err;
        err = get_nodes(&nodes, nmask, maxnode);
        if (err)
                return err;

-       return do_mbind(start, len, mode, &nodes, flags);
+       return do_mbind(start, len, mode, mode_flags, &nodes, flags);

 }
 
 /* Set the process memory policy */
 }
 
 /* Set the process memory policy */


@@ -939,13 +1083,18 @@ asmlinkage long sys_set_mempolicy(int mode, unsigned long __user *nmask,
 {
        int err;
        nodemask_t nodes;
 {
        int err;
        nodemask_t nodes;

+       unsigned short flags;

 
 

-       if (mode < 0 || mode > MPOL_MAX)
+       flags = mode & MPOL_MODE_FLAGS;
+       mode &= ~MPOL_MODE_FLAGS;
+       if ((unsigned int)mode >= MPOL_MAX)
+               return -EINVAL;
+       if ((flags & MPOL_F_STATIC_NODES) && (flags & MPOL_F_RELATIVE_NODES))

                return -EINVAL;
        err = get_nodes(&nodes, nmask, maxnode);
        if (err)
                return err;
                return -EINVAL;
        err = get_nodes(&nodes, nmask, maxnode);
        if (err)
                return err;

-       return do_set_mempolicy(mode, &nodes);
+       return do_set_mempolicy(mode, flags, &nodes);

 }
 
 asmlinkage long sys_migrate_pages(pid_t pid, unsigned long maxnode,
 }
 
 asmlinkage long sys_migrate_pages(pid_t pid, unsigned long maxnode,


@@ -1131,59 +1280,75 @@ asmlinkage long compat_sys_mbind(compat_ulong_t start, compat_ulong_t len,
  *
  * Returns effective policy for a VMA at specified address.
  * Falls back to @task or system default policy, as necessary.
  *
  * Returns effective policy for a VMA at specified address.
  * Falls back to @task or system default policy, as necessary.

- * Returned policy has extra reference count if shared, vma,
- * or some other task's policy [show_numa_maps() can pass
- * @task != current].  It is the caller's responsibility to
- * free the reference in these cases.
+ * Current or other task's task mempolicy and non-shared vma policies
+ * are protected by the task's mmap_sem, which must be held for read by
+ * the caller.
+ * Shared policies [those marked as MPOL_F_SHARED] require an extra reference
+ * count--added by the get_policy() vm_op, as appropriate--to protect against
+ * freeing by another task.  It is the caller's responsibility to free the
+ * extra reference for shared policies.

  */
  */

-static struct mempolicy * get_vma_policy(struct task_struct *task,
+static struct mempolicy *get_vma_policy(struct task_struct *task,

                struct vm_area_struct *vma, unsigned long addr)
 {
        struct mempolicy *pol = task->mempolicy;
                struct vm_area_struct *vma, unsigned long addr)
 {
        struct mempolicy *pol = task->mempolicy;

-       int shared_pol = 0;

 
        if (vma) {
                if (vma->vm_ops && vma->vm_ops->get_policy) {
 
        if (vma) {
                if (vma->vm_ops && vma->vm_ops->get_policy) {

-                       pol = vma->vm_ops->get_policy(vma, addr);
-                       shared_pol = 1; /* if pol non-NULL, add ref below */
-               } else if (vma->vm_policy &&
-                               vma->vm_policy->policy != MPOL_DEFAULT)
+                       struct mempolicy *vpol = vma->vm_ops->get_policy(vma,
+                                                                       addr);
+                       if (vpol)
+                               pol = vpol;
+               } else if (vma->vm_policy)

                        pol = vma->vm_policy;
        }
        if (!pol)
                pol = &default_policy;
                        pol = vma->vm_policy;
        }
        if (!pol)
                pol = &default_policy;

-       else if (!shared_pol && pol != current->mempolicy)
-               mpol_get(pol);  /* vma or other task's policy */

        return pol;
 }
 
        return pol;
 }
 

-/* Return a zonelist representing a mempolicy */
-static struct zonelist *zonelist_policy(gfp_t gfp, struct mempolicy *policy)
+/*
+ * Return a nodemask representing a mempolicy for filtering nodes for
+ * page allocation
+ */
+static nodemask_t *policy_nodemask(gfp_t gfp, struct mempolicy *policy)
+{
+       /* Lower zones don't get a nodemask applied for MPOL_BIND */
+       if (unlikely(policy->mode == MPOL_BIND) &&
+                       gfp_zone(gfp) >= policy_zone &&
+                       cpuset_nodemask_valid_mems_allowed(&policy->v.nodes))
+               return &policy->v.nodes;
+
+       return NULL;
+}
+
+/* Return a zonelist indicated by gfp for node representing a mempolicy */
+static struct zonelist *policy_zonelist(gfp_t gfp, struct mempolicy *policy)

 {
 {

-       int nd;
+       int nd = numa_node_id();

 
 

-       switch (policy->policy) {
+       switch (policy->mode) {

        case MPOL_PREFERRED:
        case MPOL_PREFERRED:

-               nd = policy->v.preferred_node;
-               if (nd < 0)
-                       nd = numa_node_id();
+               if (!(policy->flags & MPOL_F_LOCAL))
+                       nd = policy->v.preferred_node;

                break;
        case MPOL_BIND:
                break;
        case MPOL_BIND:

-               /* Lower zones don't get a policy applied */
-               /* Careful: current->mems_allowed might have moved */
-               if (gfp_zone(gfp) >= policy_zone)
-                       if (cpuset_zonelist_valid_mems_allowed(policy->v.zonelist))
-                               return policy->v.zonelist;
-               /*FALL THROUGH*/
+               /*
+                * Normally, MPOL_BIND allocations are node-local within the
+                * allowed nodemask.  However, if __GFP_THISNODE is set and the
+                * current node is part of the mask, we use the zonelist for
+                * the first node in the mask instead.
+                */
+               if (unlikely(gfp & __GFP_THISNODE) &&
+                               unlikely(!node_isset(nd, policy->v.nodes)))
+                       nd = first_node(policy->v.nodes);
+               break;

        case MPOL_INTERLEAVE: /* should not happen */
        case MPOL_INTERLEAVE: /* should not happen */

-       case MPOL_DEFAULT:
-               nd = numa_node_id();

                break;
        default:
                break;
        default:

-               nd = 0;

                BUG();
        }
                BUG();
        }

-       return NODE_DATA(nd)->node_zonelists + gfp_zone(gfp);
+       return node_zonelist(nd, gfp);

 }
 
 /* Do dynamic interleaving for a process */
 }
 
 /* Do dynamic interleaving for a process */


@@ -1196,36 +1361,51 @@ static unsigned interleave_nodes(struct mempolicy *policy)
        next = next_node(nid, policy->v.nodes);
        if (next >= MAX_NUMNODES)
                next = first_node(policy->v.nodes);
        next = next_node(nid, policy->v.nodes);
        if (next >= MAX_NUMNODES)
                next = first_node(policy->v.nodes);

-       me->il_next = next;
+       if (next < MAX_NUMNODES)
+               me->il_next = next;

        return nid;
 }
 
 /*
  * Depending on the memory policy provide a node from which to allocate the
  * next slab entry.
        return nid;
 }
 
 /*
  * Depending on the memory policy provide a node from which to allocate the
  * next slab entry.

+ * @policy must be protected by freeing by the caller.  If @policy is
+ * the current task's mempolicy, this protection is implicit, as only the
+ * task can change it's policy.  The system default policy requires no
+ * such protection.

  */
 unsigned slab_node(struct mempolicy *policy)
 {
  */
 unsigned slab_node(struct mempolicy *policy)
 {

-       int pol = policy ? policy->policy : MPOL_DEFAULT;
+       if (!policy || policy->flags & MPOL_F_LOCAL)
+               return numa_node_id();
+
+       switch (policy->mode) {
+       case MPOL_PREFERRED:
+               /*
+                * handled MPOL_F_LOCAL above
+                */
+               return policy->v.preferred_node;

 
 

-       switch (pol) {

        case MPOL_INTERLEAVE:
                return interleave_nodes(policy);
 
        case MPOL_INTERLEAVE:
                return interleave_nodes(policy);
 

-       case MPOL_BIND:
+       case MPOL_BIND: {

                /*
                 * Follow bind policy behavior and start allocation at the
                 * first node.
                 */
                /*
                 * Follow bind policy behavior and start allocation at the
                 * first node.
                 */

-               return zone_to_nid(policy->v.zonelist->zones[0]);
-
-       case MPOL_PREFERRED:
-               if (policy->v.preferred_node >= 0)
-                       return policy->v.preferred_node;
-               /* Fall through */
+               struct zonelist *zonelist;
+               struct zone *zone;
+               enum zone_type highest_zoneidx = gfp_zone(GFP_KERNEL);
+               zonelist = &NODE_DATA(numa_node_id())->node_zonelists[0];
+               (void)first_zones_zonelist(zonelist, highest_zoneidx,
+                                                       &policy->v.nodes,
+                                                       &zone);
+               return zone->node;
+       }

 
        default:
 
        default:

-               return numa_node_id();
+               BUG();

        }
 }
 
        }
 }
 


@@ -1234,10 +1414,13 @@ static unsigned offset_il_node(struct mempolicy *pol,
                struct vm_area_struct *vma, unsigned long off)
 {
        unsigned nnodes = nodes_weight(pol->v.nodes);
                struct vm_area_struct *vma, unsigned long off)
 {
        unsigned nnodes = nodes_weight(pol->v.nodes);

-       unsigned target = (unsigned)off % nnodes;
+       unsigned target;

        int c;
        int nid = -1;
 
        int c;
        int nid = -1;
 

+       if (!nnodes)
+               return numa_node_id();
+       target = (unsigned int)off % nnodes;

        c = 0;
        do {
                nid = next_node(nid, pol->v.nodes);
        c = 0;
        do {
                nid = next_node(nid, pol->v.nodes);


@@ -1274,38 +1457,30 @@ static inline unsigned interleave_nid(struct mempolicy *pol,
  * @vma = virtual memory area whose policy is sought
  * @addr = address in @vma for shared policy lookup and interleave policy
  * @gfp_flags = for requested zone
  * @vma = virtual memory area whose policy is sought
  * @addr = address in @vma for shared policy lookup and interleave policy
  * @gfp_flags = for requested zone

- * @mpol = pointer to mempolicy pointer for reference counted 'BIND policy
+ * @mpol = pointer to mempolicy pointer for reference counted mempolicy
+ * @nodemask = pointer to nodemask pointer for MPOL_BIND nodemask

  *
  *

- * Returns a zonelist suitable for a huge page allocation.
- * If the effective policy is 'BIND, returns pointer to policy's zonelist.
- * If it is also a policy for which get_vma_policy() returns an extra
- * reference, we must hold that reference until after allocation.
- * In that case, return policy via @mpol so hugetlb allocation can drop
- * the reference.  For non-'BIND referenced policies, we can/do drop the
- * reference here, so the caller doesn't need to know about the special case
- * for default and current task policy.
+ * Returns a zonelist suitable for a huge page allocation and a pointer
+ * to the struct mempolicy for conditional unref after allocation.
+ * If the effective policy is 'BIND, returns a pointer to the mempolicy's
+ * @nodemask for filtering the zonelist.

  */
 struct zonelist *huge_zonelist(struct vm_area_struct *vma, unsigned long addr,
  */
 struct zonelist *huge_zonelist(struct vm_area_struct *vma, unsigned long addr,

-                               gfp_t gfp_flags, struct mempolicy **mpol)
+                               gfp_t gfp_flags, struct mempolicy **mpol,
+                               nodemask_t **nodemask)

 {
 {

-       struct mempolicy *pol = get_vma_policy(current, vma, addr);

        struct zonelist *zl;
 
        struct zonelist *zl;
 

-       *mpol = NULL;           /* probably no unref needed */
-       if (pol->policy == MPOL_INTERLEAVE) {
-               unsigned nid;
+       *mpol = get_vma_policy(current, vma, addr);
+       *nodemask = NULL;       /* assume !MPOL_BIND */

 
 

-               nid = interleave_nid(pol, vma, addr, HPAGE_SHIFT);
-               __mpol_free(pol);               /* finished with pol */
-               return NODE_DATA(nid)->node_zonelists + gfp_zone(gfp_flags);
-       }
-
-       zl = zonelist_policy(GFP_HIGHUSER, pol);
-       if (unlikely(pol != &default_policy && pol != current->mempolicy)) {
-               if (pol->policy != MPOL_BIND)
-                       __mpol_free(pol);       /* finished with pol */
-               else
-                       *mpol = pol;    /* unref needed after allocation */
+       if (unlikely((*mpol)->mode == MPOL_INTERLEAVE)) {
+               zl = node_zonelist(interleave_nid(*mpol, vma, addr,
+                                               HPAGE_SHIFT), gfp_flags);
+       } else {
+               zl = policy_zonelist(gfp_flags, *mpol);
+               if ((*mpol)->mode == MPOL_BIND)
+                       *nodemask = &(*mpol)->v.nodes;

        }
        return zl;
 }
        }
        return zl;
 }


@@ -1319,9 +1494,9 @@ static struct page *alloc_page_interleave(gfp_t gfp, unsigned order,
        struct zonelist *zl;
        struct page *page;
 
        struct zonelist *zl;
        struct page *page;
 

-       zl = NODE_DATA(nid)->node_zonelists + gfp_zone(gfp);
+       zl = node_zonelist(nid, gfp);

        page = __alloc_pages(gfp, order, zl);
        page = __alloc_pages(gfp, order, zl);

-       if (page && page_zone(page) == zl->zones[0])
+       if (page && page_zone(page) == zonelist_zone(&zl->_zonerefs[0]))

                inc_zone_page_state(page, NUMA_INTERLEAVE_HIT);
        return page;
 }
                inc_zone_page_state(page, NUMA_INTERLEAVE_HIT);
        return page;
 }


@@ -1356,25 +1531,27 @@ alloc_page_vma(gfp_t gfp, struct vm_area_struct *vma, unsigned long addr)
 
        cpuset_update_task_memory_state();
 
 
        cpuset_update_task_memory_state();
 

-       if (unlikely(pol->policy == MPOL_INTERLEAVE)) {
+       if (unlikely(pol->mode == MPOL_INTERLEAVE)) {

                unsigned nid;
 
                nid = interleave_nid(pol, vma, addr, PAGE_SHIFT);
                unsigned nid;
 
                nid = interleave_nid(pol, vma, addr, PAGE_SHIFT);

+               mpol_cond_put(pol);

                return alloc_page_interleave(gfp, 0, nid);
        }
                return alloc_page_interleave(gfp, 0, nid);
        }

-       zl = zonelist_policy(gfp, pol);
-       if (pol != &default_policy && pol != current->mempolicy) {
+       zl = policy_zonelist(gfp, pol);
+       if (unlikely(mpol_needs_cond_ref(pol))) {

                /*
                /*

-                * slow path: ref counted policy -- shared or vma
+                * slow path: ref counted shared policy

                 */
                 */

-               struct page *page =  __alloc_pages(gfp, 0, zl);
-               __mpol_free(pol);
+               struct page *page =  __alloc_pages_nodemask(gfp, 0,
+                                               zl, policy_nodemask(gfp, pol));
+               __mpol_put(pol);

                return page;
        }
        /*
         * fast path:  default or task policy
         */
                return page;
        }
        /*
         * fast path:  default or task policy
         */

-       return __alloc_pages(gfp, 0, zl);
+       return __alloc_pages_nodemask(gfp, 0, zl, policy_nodemask(gfp, pol));

 }
 
 /**
 }
 
 /**


@@ -1404,22 +1581,28 @@ struct page *alloc_pages_current(gfp_t gfp, unsigned order)
                cpuset_update_task_memory_state();
        if (!pol || in_interrupt() || (gfp & __GFP_THISNODE))
                pol = &default_policy;
                cpuset_update_task_memory_state();
        if (!pol || in_interrupt() || (gfp & __GFP_THISNODE))
                pol = &default_policy;

-       if (pol->policy == MPOL_INTERLEAVE)
+
+       /*
+        * No reference counting needed for current->mempolicy
+        * nor system default_policy
+        */
+       if (pol->mode == MPOL_INTERLEAVE)

                return alloc_page_interleave(gfp, order, interleave_nodes(pol));
                return alloc_page_interleave(gfp, order, interleave_nodes(pol));

-       return __alloc_pages(gfp, order, zonelist_policy(gfp, pol));
+       return __alloc_pages_nodemask(gfp, order,
+                       policy_zonelist(gfp, pol), policy_nodemask(gfp, pol));

 }
 EXPORT_SYMBOL(alloc_pages_current);
 
 /*
 }
 EXPORT_SYMBOL(alloc_pages_current);
 
 /*

- * If mpol_copy() sees current->cpuset == cpuset_being_rebound, then it
+ * If mpol_dup() sees current->cpuset == cpuset_being_rebound, then it

  * rebinds the mempolicy its copying by calling mpol_rebind_policy()
  * with the mems_allowed returned by cpuset_mems_allowed().  This
  * keeps mempolicies cpuset relative after its cpuset moves.  See
  * further kernel/cpuset.c update_nodemask().
  */
 
  * rebinds the mempolicy its copying by calling mpol_rebind_policy()
  * with the mems_allowed returned by cpuset_mems_allowed().  This
  * keeps mempolicies cpuset relative after its cpuset moves.  See
  * further kernel/cpuset.c update_nodemask().
  */
 

-/* Slow path of a mempolicy copy */
-struct mempolicy *__mpol_copy(struct mempolicy *old)
+/* Slow path of a mempolicy duplicate */
+struct mempolicy *__mpol_dup(struct mempolicy *old)

 {
        struct mempolicy *new = kmem_cache_alloc(policy_cache, GFP_KERNEL);
 
 {
        struct mempolicy *new = kmem_cache_alloc(policy_cache, GFP_KERNEL);
 


@@ -1431,55 +1614,64 @@ struct mempolicy *__mpol_copy(struct mempolicy *old)
        }
        *new = *old;
        atomic_set(&new->refcnt, 1);
        }
        *new = *old;
        atomic_set(&new->refcnt, 1);

-       if (new->policy == MPOL_BIND) {
-               int sz = ksize(old->v.zonelist);
-               new->v.zonelist = kmemdup(old->v.zonelist, sz, GFP_KERNEL);
-               if (!new->v.zonelist) {
-                       kmem_cache_free(policy_cache, new);
-                       return ERR_PTR(-ENOMEM);
-               }
-       }

        return new;
 }
 
        return new;
 }
 

+/*
+ * If *frompol needs [has] an extra ref, copy *frompol to *tompol ,
+ * eliminate the * MPOL_F_* flags that require conditional ref and
+ * [NOTE!!!] drop the extra ref.  Not safe to reference *frompol directly
+ * after return.  Use the returned value.
+ *
+ * Allows use of a mempolicy for, e.g., multiple allocations with a single
+ * policy lookup, even if the policy needs/has extra ref on lookup.
+ * shmem_readahead needs this.
+ */
+struct mempolicy *__mpol_cond_copy(struct mempolicy *tompol,
+                                               struct mempolicy *frompol)
+{
+       if (!mpol_needs_cond_ref(frompol))
+               return frompol;
+
+       *tompol = *frompol;
+       tompol->flags &= ~MPOL_F_SHARED;        /* copy doesn't need unref */
+       __mpol_put(frompol);
+       return tompol;
+}
+
+static int mpol_match_intent(const struct mempolicy *a,
+                            const struct mempolicy *b)
+{
+       if (a->flags != b->flags)
+               return 0;
+       if (!mpol_store_user_nodemask(a))
+               return 1;
+       return nodes_equal(a->w.user_nodemask, b->w.user_nodemask);
+}
+

 /* Slow path of a mempolicy comparison */
 int __mpol_equal(struct mempolicy *a, struct mempolicy *b)
 {
        if (!a || !b)
                return 0;
 /* Slow path of a mempolicy comparison */
 int __mpol_equal(struct mempolicy *a, struct mempolicy *b)
 {
        if (!a || !b)
                return 0;

-       if (a->policy != b->policy)
+       if (a->mode != b->mode)

                return 0;
                return 0;

-       switch (a->policy) {
-       case MPOL_DEFAULT:
-               return 1;
+       if (a->mode != MPOL_DEFAULT && !mpol_match_intent(a, b))
+               return 0;
+       switch (a->mode) {
+       case MPOL_BIND:
+               /* Fall through */

        case MPOL_INTERLEAVE:
                return nodes_equal(a->v.nodes, b->v.nodes);
        case MPOL_PREFERRED:
        case MPOL_INTERLEAVE:
                return nodes_equal(a->v.nodes, b->v.nodes);
        case MPOL_PREFERRED:

-               return a->v.preferred_node == b->v.preferred_node;
-       case MPOL_BIND: {
-               int i;
-               for (i = 0; a->v.zonelist->zones[i]; i++)
-                       if (a->v.zonelist->zones[i] != b->v.zonelist->zones[i])
-                               return 0;
-               return b->v.zonelist->zones[i] == NULL;
-       }
+               return a->v.preferred_node == b->v.preferred_node &&
+                       a->flags == b->flags;

        default:
                BUG();
                return 0;
        }
 }
 
        default:
                BUG();
                return 0;
        }
 }
 

-/* Slow path of a mpol destructor. */
-void __mpol_free(struct mempolicy *p)
-{
-       if (!atomic_dec_and_test(&p->refcnt))
-               return;
-       if (p->policy == MPOL_BIND)
-               kfree(p->v.zonelist);
-       p->policy = MPOL_DEFAULT;
-       kmem_cache_free(policy_cache, p);
-}
-

 /*
  * Shared memory backing store policy support.
  *
 /*
  * Shared memory backing store policy support.
  *


@@ -1542,7 +1734,7 @@ static void sp_insert(struct shared_policy *sp, struct sp_node *new)
        rb_link_node(&new->nd, parent, p);
        rb_insert_color(&new->nd, &sp->root);
        pr_debug("inserting %lx-%lx: %d\n", new->start, new->end,
        rb_link_node(&new->nd, parent, p);
        rb_insert_color(&new->nd, &sp->root);
        pr_debug("inserting %lx-%lx: %d\n", new->start, new->end,

-                new->policy ? new->policy->policy : 0);
+                new->policy ? new->policy->mode : 0);

 }
 
 /* Find shared policy intersecting idx */
 }
 
 /* Find shared policy intersecting idx */


@@ -1568,7 +1760,7 @@ static void sp_delete(struct shared_policy *sp, struct sp_node *n)
 {
        pr_debug("deleting %lx-l%lx\n", n->start, n->end);
        rb_erase(&n->nd, &sp->root);
 {
        pr_debug("deleting %lx-l%lx\n", n->start, n->end);
        rb_erase(&n->nd, &sp->root);

-       mpol_free(n->policy);
+       mpol_put(n->policy);

        kmem_cache_free(sn_cache, n);
 }
 
        kmem_cache_free(sn_cache, n);
 }
 


@@ -1582,6 +1774,7 @@ static struct sp_node *sp_alloc(unsigned long start, unsigned long end,
        n->start = start;
        n->end = end;
        mpol_get(pol);
        n->start = start;
        n->end = end;
        mpol_get(pol);

+       pol->flags |= MPOL_F_SHARED;    /* for unref */

        n->policy = pol;
        return n;
 }
        n->policy = pol;
        return n;
 }


@@ -1628,14 +1821,14 @@ restart:
                sp_insert(sp, new);
        spin_unlock(&sp->lock);
        if (new2) {
                sp_insert(sp, new);
        spin_unlock(&sp->lock);
        if (new2) {

-               mpol_free(new2->policy);
+               mpol_put(new2->policy);

                kmem_cache_free(sn_cache, new2);
        }
        return 0;
 }
 
                kmem_cache_free(sn_cache, new2);
        }
        return 0;
 }
 

-void mpol_shared_policy_init(struct shared_policy *info, int policy,
-                               nodemask_t *policy_nodes)
+void mpol_shared_policy_init(struct shared_policy *info, unsigned short policy,
+                       unsigned short flags, nodemask_t *policy_nodes)

 {
        info->root = RB_ROOT;
        spin_lock_init(&info->lock);
 {
        info->root = RB_ROOT;
        spin_lock_init(&info->lock);


@@ -1643,8 +1836,8 @@ void mpol_shared_policy_init(struct shared_policy *info, int policy,
        if (policy != MPOL_DEFAULT) {
                struct mempolicy *newpol;
 
        if (policy != MPOL_DEFAULT) {
                struct mempolicy *newpol;
 

-               /* Falls back to MPOL_DEFAULT on any error */
-               newpol = mpol_new(policy, policy_nodes);
+               /* Falls back to NULL policy [MPOL_DEFAULT] on any error */
+               newpol = mpol_new(policy, flags, policy_nodes);

                if (!IS_ERR(newpol)) {
                        /* Create pseudo-vma that contains just the policy */
                        struct vm_area_struct pvma;
                if (!IS_ERR(newpol)) {
                        /* Create pseudo-vma that contains just the policy */
                        struct vm_area_struct pvma;


@@ -1653,7 +1846,7 @@ void mpol_shared_policy_init(struct shared_policy *info, int policy,
                        /* Policy covers entire file */
                        pvma.vm_end = TASK_SIZE;
                        mpol_set_shared_policy(info, &pvma, newpol);
                        /* Policy covers entire file */
                        pvma.vm_end = TASK_SIZE;
                        mpol_set_shared_policy(info, &pvma, newpol);

-                       mpol_free(newpol);
+                       mpol_put(newpol);

                }
        }
 }
                }
        }
 }


@@ -1665,9 +1858,10 @@ int mpol_set_shared_policy(struct shared_policy *info,
        struct sp_node *new = NULL;
        unsigned long sz = vma_pages(vma);
 
        struct sp_node *new = NULL;
        unsigned long sz = vma_pages(vma);
 

-       pr_debug("set_shared_policy %lx sz %lu %d %lx\n",
+       pr_debug("set_shared_policy %lx sz %lu %d %d %lx\n",

                 vma->vm_pgoff,
                 vma->vm_pgoff,

-                sz, npol? npol->policy : -1,
+                sz, npol ? npol->mode : -1,
+                npol ? npol->flags : -1,

                 npol ? nodes_addr(npol->v.nodes)[0] : -1);
 
        if (npol) {
                 npol ? nodes_addr(npol->v.nodes)[0] : -1);
 
        if (npol) {


@@ -1695,7 +1889,7 @@ void mpol_free_shared_policy(struct shared_policy *p)
                n = rb_entry(next, struct sp_node, nd);
                next = rb_next(&n->nd);
                rb_erase(&n->nd, &p->root);
                n = rb_entry(next, struct sp_node, nd);
                next = rb_next(&n->nd);
                rb_erase(&n->nd, &p->root);

-               mpol_free(n->policy);
+               mpol_put(n->policy);

                kmem_cache_free(sn_cache, n);
        }
        spin_unlock(&p->lock);
                kmem_cache_free(sn_cache, n);
        }
        spin_unlock(&p->lock);


@@ -1740,108 +1934,23 @@ void __init numa_policy_init(void)
        if (unlikely(nodes_empty(interleave_nodes)))
                node_set(prefer, interleave_nodes);
 
        if (unlikely(nodes_empty(interleave_nodes)))
                node_set(prefer, interleave_nodes);
 

-       if (do_set_mempolicy(MPOL_INTERLEAVE, &interleave_nodes))
+       if (do_set_mempolicy(MPOL_INTERLEAVE, 0, &interleave_nodes))

                printk("numa_policy_init: interleaving failed\n");
 }
 
 /* Reset policy of current process to default */
 void numa_default_policy(void)
 {
                printk("numa_policy_init: interleaving failed\n");
 }
 
 /* Reset policy of current process to default */
 void numa_default_policy(void)
 {

-       do_set_mempolicy(MPOL_DEFAULT, NULL);
-}
-
-/* Migrate a policy to a different set of nodes */
-static void mpol_rebind_policy(struct mempolicy *pol,
-                              const nodemask_t *newmask)
-{
-       nodemask_t *mpolmask;
-       nodemask_t tmp;
-
-       if (!pol)
-               return;
-       mpolmask = &pol->cpuset_mems_allowed;
-       if (nodes_equal(*mpolmask, *newmask))
-               return;
-
-       switch (pol->policy) {
-       case MPOL_DEFAULT:
-               break;
-       case MPOL_INTERLEAVE:
-               nodes_remap(tmp, pol->v.nodes, *mpolmask, *newmask);
-               pol->v.nodes = tmp;
-               *mpolmask = *newmask;
-               current->il_next = node_remap(current->il_next,
-                                               *mpolmask, *newmask);
-               break;
-       case MPOL_PREFERRED:
-               pol->v.preferred_node = node_remap(pol->v.preferred_node,
-                                               *mpolmask, *newmask);
-               *mpolmask = *newmask;
-               break;
-       case MPOL_BIND: {
-               nodemask_t nodes;
-               struct zone **z;
-               struct zonelist *zonelist;
-
-               nodes_clear(nodes);
-               for (z = pol->v.zonelist->zones; *z; z++)
-                       node_set(zone_to_nid(*z), nodes);
-               nodes_remap(tmp, nodes, *mpolmask, *newmask);
-               nodes = tmp;
-
-               zonelist = bind_zonelist(&nodes);
-
-               /* If no mem, then zonelist is NULL and we keep old zonelist.
-                * If that old zonelist has no remaining mems_allowed nodes,
-                * then zonelist_policy() will "FALL THROUGH" to MPOL_DEFAULT.
-                */
-
-               if (!IS_ERR(zonelist)) {
-                       /* Good - got mem - substitute new zonelist */
-                       kfree(pol->v.zonelist);
-                       pol->v.zonelist = zonelist;
-               }
-               *mpolmask = *newmask;
-               break;
-       }
-       default:
-               BUG();
-               break;
-       }
-}
-
-/*
- * Wrapper for mpol_rebind_policy() that just requires task
- * pointer, and updates task mempolicy.
- */
-
-void mpol_rebind_task(struct task_struct *tsk, const nodemask_t *new)
-{
-       mpol_rebind_policy(tsk->mempolicy, new);
-}
-
-/*
- * Rebind each vma in mm to new nodemask.
- *
- * Call holding a reference to mm.  Takes mm->mmap_sem during call.
- */
-
-void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new)
-{
-       struct vm_area_struct *vma;
-
-       down_write(&mm->mmap_sem);
-       for (vma = mm->mmap; vma; vma = vma->vm_next)
-               mpol_rebind_policy(vma->vm_policy, new);
-       up_write(&mm->mmap_sem);
+       do_set_mempolicy(MPOL_DEFAULT, 0, NULL);

 }
 
 /*
 }
 
 /*

- * Display pages allocated per node and memory policy via /proc.
+ * "local" is pseudo-policy:  MPOL_PREFERRED with MPOL_F_LOCAL flag
+ * Used only for mpol_to_str()

  */
  */

-
+#define MPOL_LOCAL (MPOL_INTERLEAVE + 1)

 static const char * const policy_types[] =
 static const char * const policy_types[] =

-       { "default", "prefer", "bind", "interleave" };
+       { "default", "prefer", "bind", "interleave", "local" };

 
 /*
  * Convert a mempolicy into a string.
 
 /*
  * Convert a mempolicy into a string.


@@ -1853,7 +1962,13 @@ static inline int mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol)
        char *p = buffer;
        int l;
        nodemask_t nodes;
        char *p = buffer;
        int l;
        nodemask_t nodes;

-       int mode = pol ? pol->policy : MPOL_DEFAULT;
+       unsigned short mode;
+       unsigned short flags = pol ? pol->flags : 0;
+
+       if (!pol || pol == &default_policy)
+               mode = MPOL_DEFAULT;
+       else
+               mode = pol->mode;

 
        switch (mode) {
        case MPOL_DEFAULT:
 
        switch (mode) {
        case MPOL_DEFAULT:


@@ -1862,13 +1977,14 @@ static inline int mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol)
 
        case MPOL_PREFERRED:
                nodes_clear(nodes);
 
        case MPOL_PREFERRED:
                nodes_clear(nodes);

-               node_set(pol->v.preferred_node, nodes);
+               if (flags & MPOL_F_LOCAL)
+                       mode = MPOL_LOCAL;      /* pseudo-policy */
+               else
+                       node_set(pol->v.preferred_node, nodes);

                break;
 
        case MPOL_BIND:
                break;
 
        case MPOL_BIND:

-               get_zonemask(pol, &nodes);
-               break;
-
+               /* Fall through */

        case MPOL_INTERLEAVE:
                nodes = pol->v.nodes;
                break;
        case MPOL_INTERLEAVE:
                nodes = pol->v.nodes;
                break;


@@ -1879,12 +1995,25 @@ static inline int mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol)
        }
 
        l = strlen(policy_types[mode]);
        }
 
        l = strlen(policy_types[mode]);

-       if (buffer + maxlen < p + l + 1)
-               return -ENOSPC;
+       if (buffer + maxlen < p + l + 1)
+               return -ENOSPC;

 
        strcpy(p, policy_types[mode]);
        p += l;
 
 
        strcpy(p, policy_types[mode]);
        p += l;
 

+       if (flags & MPOL_MODE_FLAGS) {
+               int need_bar = 0;
+
+               if (buffer + maxlen < p + 2)
+                       return -ENOSPC;
+               *p++ = '=';
+
+               if (flags & MPOL_F_STATIC_NODES)
+                       p += sprintf(p, "%sstatic", need_bar++ ? "|" : "");
+               if (flags & MPOL_F_RELATIVE_NODES)
+                       p += sprintf(p, "%srelative", need_bar++ ? "|" : "");
+       }
+

        if (!nodes_empty(nodes)) {
                if (buffer + maxlen < p + 2)
                        return -ENOSPC;
        if (!nodes_empty(nodes)) {
                if (buffer + maxlen < p + 2)
                        return -ENOSPC;


@@ -1966,6 +2095,9 @@ static inline void check_huge_range(struct vm_area_struct *vma,
 }
 #endif
 
 }
 #endif
 

+/*
+ * Display pages allocated per node and memory policy via /proc.
+ */

 int show_numa_map(struct seq_file *m, void *v)
 {
        struct proc_maps_private *priv = m->private;
 int show_numa_map(struct seq_file *m, void *v)
 {
        struct proc_maps_private *priv = m->private;


@@ -1986,11 +2118,7 @@ int show_numa_map(struct seq_file *m, void *v)
 
        pol = get_vma_policy(priv->task, vma, vma->vm_start);
        mpol_to_str(buffer, sizeof(buffer), pol);
 
        pol = get_vma_policy(priv->task, vma, vma->vm_start);
        mpol_to_str(buffer, sizeof(buffer), pol);

-       /*
-        * unref shared or other task's mempolicy
-        */
-       if (pol != &default_policy && pol != current->mempolicy)
-               __mpol_free(pol);
+       mpol_cond_put(pol);

 
        seq_printf(m, "%08lx %s", vma->vm_start, buffer);
 
 
        seq_printf(m, "%08lx %s", vma->vm_start, buffer);