1 files changed, 31 insertions, 19 deletions

diff --git a/mm/shmem.c b/mm/shmem.c
index 197ca5eccbae..39de1d6a077a 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -335,19 +335,19 @@ static unsigned shmem_find_get_pages_and_swap(struct address_space *mapping,
                                         pgoff_t start, unsigned int nr_pages,
                                         struct page **pages, pgoff_t *indices)
 {
-        unsigned int i;
-        unsigned int ret;
-        unsigned int nr_found;
+        void **slot;
+        unsigned int ret = 0;
+        struct radix_tree_iter iter;
+
+        if (!nr_pages)
+                return 0;
 
         rcu_read_lock();
 restart:
-        nr_found = radix_tree_gang_lookup_slot(&mapping->page_tree,
-                                (void ***)pages, indices, start, nr_pages);
-        ret = 0;
-        for (i = 0; i < nr_found; i++) {
+        radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, start) {
                 struct page *page;
 repeat:
-                page = radix_tree_deref_slot((void **)pages[i]);
+                page = radix_tree_deref_slot(slot);
                 if (unlikely(!page))
                         continue;
                 if (radix_tree_exception(page)) {
@@ -364,17 +364,16 @@ repeat:
                         goto repeat;
 
                 /* Has the page moved? */
-                if (unlikely(page != *((void **)pages[i]))) {
+                if (unlikely(page != *slot)) {
                         page_cache_release(page);
                         goto repeat;
                 }
 export:
-                indices[ret] = indices[i];
+                indices[ret] = iter.index;
                 pages[ret] = page;
-                ret++;
+                if (++ret == nr_pages)
+                        break;
         }
-        if (unlikely(!ret && nr_found))
-                goto restart;
         rcu_read_unlock();
         return ret;
 }
@@ -889,7 +888,7 @@ static void shmem_show_mpol(struct seq_file *seq, struct mempolicy *mpol)
         if (!mpol || mpol->mode == MPOL_DEFAULT)
                 return;         /* show nothing */
 
-        mpol_to_str(buffer, sizeof(buffer), mpol, 1);
+        mpol_to_str(buffer, sizeof(buffer), mpol);
 
         seq_printf(seq, ",mpol=%s", buffer);
 }
@@ -2386,6 +2385,7 @@ static int shmem_parse_options(char *options, struct shmem_sb_info *sbinfo,
                                bool remount)
 {
         char *this_char, *value, *rest;
+        struct mempolicy *mpol = NULL;
         uid_t uid;
         gid_t gid;
 
@@ -2414,7 +2414,7 @@ static int shmem_parse_options(char *options, struct shmem_sb_info *sbinfo,
                         printk(KERN_ERR
                             "tmpfs: No value for mount option '%s'\n",
                             this_char);
-                        return 1;
+                        goto error;
                 }
 
                 if (!strcmp(this_char,"size")) {
@@ -2463,19 +2463,24 @@ static int shmem_parse_options(char *options, struct shmem_sb_info *sbinfo,
                         if (!gid_valid(sbinfo->gid))
                                 goto bad_val;
                 } else if (!strcmp(this_char,"mpol")) {
-                        if (mpol_parse_str(value, &sbinfo->mpol, 1))
+                        mpol_put(mpol);
+                        mpol = NULL;
+                        if (mpol_parse_str(value, &mpol))
                                 goto bad_val;
                 } else {
                         printk(KERN_ERR "tmpfs: Bad mount option %s\n",
                                this_char);
-                        return 1;
+                        goto error;
                 }
         }
+        sbinfo->mpol = mpol;
         return 0;
 
 bad_val:
         printk(KERN_ERR "tmpfs: Bad value '%s' for mount option '%s'\n",
                value, this_char);
+error:
+        mpol_put(mpol);
         return 1;
 
 }
@@ -2487,6 +2492,7 @@ static int shmem_remount_fs(struct super_block *sb, int *flags, char *data)
         unsigned long inodes;
         int error = -EINVAL;
 
+        config.mpol = NULL;
         if (shmem_parse_options(data, &config, true))
                 return error;
 
@@ -2511,8 +2517,13 @@ static int shmem_remount_fs(struct super_block *sb, int *flags, char *data)
         sbinfo->max_inodes  = config.max_inodes;
         sbinfo->free_inodes = config.max_inodes - inodes;
 
-        mpol_put(sbinfo->mpol);
-        sbinfo->mpol        = config.mpol;      /* transfers initial ref */
+        /*
+         * Preserve previous mempolicy unless mpol remount option was specified.
+         */
+        if (config.mpol) {
+                mpol_put(sbinfo->mpol);
+                sbinfo->mpol = config.mpol;     /* transfers initial ref */
+        }
 out:
         spin_unlock(&sbinfo->stat_lock);
         return error;
@@ -2545,6 +2556,7 @@ static void shmem_put_super(struct super_block *sb)
         struct shmem_sb_info *sbinfo = SHMEM_SB(sb);
 
         percpu_counter_destroy(&sbinfo->used_blocks);
+        mpol_put(sbinfo->mpol);
         kfree(sbinfo);
         sb->s_fs_info = NULL;
 }