hugetlb: allow bulk updating in hugetlb_*_quota()

Add a second parameter 'delta' to hugetlb_get_quota and hugetlb_put_quota to
allow bulk updating of the sbinfo->free_blocks counter.  This will be used by
the next patch in the series.

Signed-off-by: Adam Litke <agl@us.ibm.com>
Cc: Ken Chen <kenchen@google.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: David Gibson <hermes@gibson.dropbear.id.au>
Cc: William Lee Irwin III <wli@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index 6513f56..09ee07f 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -858,15 +858,15 @@
 	return -ENOMEM;
 }
 
-int hugetlb_get_quota(struct address_space *mapping)
+int hugetlb_get_quota(struct address_space *mapping, long delta)
 {
 	int ret = 0;
 	struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(mapping->host->i_sb);
 
 	if (sbinfo->free_blocks > -1) {
 		spin_lock(&sbinfo->stat_lock);
-		if (sbinfo->free_blocks > 0)
-			sbinfo->free_blocks--;
+		if (sbinfo->free_blocks - delta >= 0)
+			sbinfo->free_blocks -= delta;
 		else
 			ret = -ENOMEM;
 		spin_unlock(&sbinfo->stat_lock);
@@ -875,13 +875,13 @@
 	return ret;
 }
 
-void hugetlb_put_quota(struct address_space *mapping)
+void hugetlb_put_quota(struct address_space *mapping, long delta)
 {
 	struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(mapping->host->i_sb);
 
 	if (sbinfo->free_blocks > -1) {
 		spin_lock(&sbinfo->stat_lock);
-		sbinfo->free_blocks++;
+		sbinfo->free_blocks += delta;
 		spin_unlock(&sbinfo->stat_lock);
 	}
 }