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;
 }