4 files changed, 33 insertions, 26 deletions

diff --git a/include/linux/mempolicy.h b/include/linux/mempolicy.h
index b8b3da7a3315..389a06e8ee21 100644
--- a/include/linux/mempolicy.h
+++ b/include/linux/mempolicy.h
@@ -9,12 +9,13 @@
  */
 
 /* Policies */
-#define MPOL_DEFAULT    0
-#define MPOL_PREFERRED  1
-#define MPOL_BIND       2
-#define MPOL_INTERLEAVE 3
-
-#define MPOL_MAX MPOL_INTERLEAVE
+enum {
+        MPOL_DEFAULT,
+        MPOL_PREFERRED,
+        MPOL_BIND,
+        MPOL_INTERLEAVE,
+        MPOL_MAX,       /* always last member of enum */
+};
 
 /* Flags for get_mem_policy */
 #define MPOL_F_NODE     (1<<0)  /* return next IL mode instead of node mask */
@@ -64,7 +65,7 @@ struct mm_struct;
  */
 struct mempolicy {
         atomic_t refcnt;
-        short policy;   /* See MPOL_* above */
+        unsigned short policy;  /* See MPOL_* above */
         union {
                 short            preferred_node; /* preferred */
                 nodemask_t       nodes;         /* interleave/bind */
@@ -134,7 +135,7 @@ struct shared_policy {
         spinlock_t lock;
 };
 
-void mpol_shared_policy_init(struct shared_policy *info, int policy,
+void mpol_shared_policy_init(struct shared_policy *info, unsigned short policy,
                                 nodemask_t *nodes);
 int mpol_set_shared_policy(struct shared_policy *info,
                                 struct vm_area_struct *vma,
@@ -202,7 +203,7 @@ static inline int mpol_set_shared_policy(struct shared_policy *info,
 }
 
 static inline void mpol_shared_policy_init(struct shared_policy *info,
-                                        int policy, nodemask_t *nodes)
+                                unsigned short policy, nodemask_t *nodes)
 {
 }
 
diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h
index 8d5fb36ea047..639a4070708e 100644
--- a/include/linux/shmem_fs.h
+++ b/include/linux/shmem_fs.h
@@ -34,7 +34,7 @@ struct shmem_sb_info {
         uid_t uid;                  /* Mount uid for root directory */
         gid_t gid;                  /* Mount gid for root directory */
         mode_t mode;                /* Mount mode for root directory */
-        int policy;                 /* Default NUMA memory alloc policy */
+        unsigned short policy;      /* Default NUMA memory alloc policy */
         nodemask_t policy_nodes;    /* nodemask for preferred and bind */
 };
 
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index acb5ee3587c3..1311dc4a3888 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -114,7 +114,7 @@ static void mpol_rebind_policy(struct mempolicy *pol,
                                const nodemask_t *newmask);
 
 /* Do sanity checking on a policy */
-static int mpol_check_policy(int mode, nodemask_t *nodes)
+static int mpol_check_policy(unsigned short mode, nodemask_t *nodes)
 {
         int was_empty, is_empty;
 
@@ -159,6 +159,8 @@ static int mpol_check_policy(int mode, nodemask_t *nodes)
                 if (!was_empty && is_empty)
                         return -EINVAL;
                 break;
+        default:
+                BUG();
         }
         return 0;
 }
@@ -185,7 +187,7 @@ static int is_valid_nodemask(nodemask_t *nodemask)
 }
 
 /* Create a new policy */
-static struct mempolicy *mpol_new(int mode, nodemask_t *nodes)
+static struct mempolicy *mpol_new(unsigned short mode, nodemask_t *nodes)
 {
         struct mempolicy *policy;
 
@@ -218,6 +220,8 @@ static struct mempolicy *mpol_new(int mode, nodemask_t *nodes)
                 }
                 policy->v.nodes = *nodes;
                 break;
+        default:
+                BUG();
         }
         policy->policy = mode;
         policy->cpuset_mems_allowed = cpuset_mems_allowed(current);
@@ -462,7 +466,7 @@ static void mpol_set_task_struct_flag(void)
 }
 
 /* Set the process memory policy */
-static long do_set_mempolicy(int mode, nodemask_t *nodes)
+static long do_set_mempolicy(unsigned short mode, nodemask_t *nodes)
 {
         struct mempolicy *new;
 
@@ -759,7 +763,7 @@ static struct page *new_vma_page(struct page *page, unsigned long private, int *
 #endif
 
 static long do_mbind(unsigned long start, unsigned long len,
-                     unsigned long mode, nodemask_t *nmask,
+                     unsigned short mode, nodemask_t *nmask,
                      unsigned long flags)
 {
         struct vm_area_struct *vma;
@@ -769,9 +773,8 @@ static long do_mbind(unsigned long start, unsigned long len,
         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;
@@ -804,7 +807,7 @@ static long do_mbind(unsigned long start, unsigned long len,
         if (!new)
                 flags |= MPOL_MF_DISCONTIG_OK;
 
-        pr_debug("mbind %lx-%lx mode:%ld nodes:%lx\n",start,start+len,
+        pr_debug("mbind %lx-%lx mode:%d nodes:%lx\n", start, start + len,
                  mode, nmask ? nodes_addr(*nmask)[0] : -1);
 
         down_write(&mm->mmap_sem);
@@ -905,6 +908,8 @@ asmlinkage long sys_mbind(unsigned long start, unsigned long len,
         nodemask_t nodes;
         int err;
 
+        if (mode >= MPOL_MAX)
+                return -EINVAL;
         err = get_nodes(&nodes, nmask, maxnode);
         if (err)
                 return err;
@@ -918,7 +923,7 @@ asmlinkage long sys_set_mempolicy(int mode, unsigned long __user *nmask,
         int err;
         nodemask_t nodes;
 
-        if (mode < 0 || mode > MPOL_MAX)
+        if (mode < 0 || mode >= MPOL_MAX)
                 return -EINVAL;
         err = get_nodes(&nodes, nmask, maxnode);
         if (err)
@@ -1201,7 +1206,7 @@ static unsigned interleave_nodes(struct mempolicy *policy)
  */
 unsigned slab_node(struct mempolicy *policy)
 {
-        int pol = policy ? policy->policy : MPOL_DEFAULT;
+        unsigned short pol = policy ? policy->policy : MPOL_DEFAULT;
 
         switch (pol) {
         case MPOL_INTERLEAVE:
@@ -1635,7 +1640,7 @@ restart:
         return 0;
 }
 
-void mpol_shared_policy_init(struct shared_policy *info, int policy,
+void mpol_shared_policy_init(struct shared_policy *info, unsigned short policy,
                                 nodemask_t *policy_nodes)
 {
         info->root = RB_ROOT;
@@ -1830,7 +1835,7 @@ static inline int mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol)
         char *p = buffer;
         int l;
         nodemask_t nodes;
-        int mode = pol ? pol->policy : MPOL_DEFAULT;
+        unsigned short mode = pol ? pol->policy : MPOL_DEFAULT;
 
         switch (mode) {
         case MPOL_DEFAULT:
diff --git a/mm/shmem.c b/mm/shmem.c
index f514dd392cd9..d8ef7ba831a5 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1079,7 +1079,8 @@ redirty:
 
 #ifdef CONFIG_NUMA
 #ifdef CONFIG_TMPFS
-static int shmem_parse_mpol(char *value, int *policy, nodemask_t *policy_nodes)
+static int shmem_parse_mpol(char *value, unsigned short *policy,
+                            nodemask_t *policy_nodes)
 {
         char *nodelist = strchr(value, ':');
         int err = 1;
@@ -1128,7 +1129,7 @@ out:
         return err;
 }
 
-static void shmem_show_mpol(struct seq_file *seq, int policy,
+static void shmem_show_mpol(struct seq_file *seq, unsigned short policy,
                             const nodemask_t policy_nodes)
 {
         char *policy_string;
@@ -1197,13 +1198,13 @@ static struct page *shmem_alloc_page(gfp_t gfp,
 }
 #else /* !CONFIG_NUMA */
 #ifdef CONFIG_TMPFS
-static inline int shmem_parse_mpol(char *value, int *policy,
+static inline int shmem_parse_mpol(char *value, unsigned short *policy,
                                                 nodemask_t *policy_nodes)
 {
         return 1;
 }
 
-static inline void shmem_show_mpol(struct seq_file *seq, int policy,
+static inline void shmem_show_mpol(struct seq_file *seq, unsigned short policy,
                             const nodemask_t policy_nodes)
 {
 }