ext4: remove ext4_new_blocks() and call ext4_mb_new_blocks() directly

There was only one caller of the compatibility function
ext4_new_blocks(), in balloc.c's ext4_alloc_blocks().  Change it to
call ext4_mb_new_blocks() directly, and remove ext4_new_blocks()
altogether.  This cleans up the code, by removing two extra functions
from the call chain, and hopefully saving some stack usage.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 5b0881216..5120243 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -547,6 +547,7 @@
 				int indirect_blks, int blks,
 				ext4_fsblk_t new_blocks[4], int *err)
 {
+	struct ext4_allocation_request ar;
 	int target, i;
 	unsigned long count = 0, blk_allocated = 0;
 	int index = 0;
@@ -595,10 +596,17 @@
 	if (!target)
 		goto allocated;
 	/* Now allocate data blocks */
-	count = target;
-	/* allocating blocks for data blocks */
-	current_block = ext4_new_blocks(handle, inode, iblock,
-						goal, &count, err);
+	memset(&ar, 0, sizeof(ar));
+	ar.inode = inode;
+	ar.goal = goal;
+	ar.len = target;
+	ar.logical = iblock;
+	if (S_ISREG(inode->i_mode))
+		/* enable in-core preallocation only for regular files */
+		ar.flags = EXT4_MB_HINT_DATA;
+
+	current_block = ext4_mb_new_blocks(handle, &ar, err);
+
 	if (*err && (target == blks)) {
 		/*
 		 * if the allocation failed and we didn't allocate
@@ -614,7 +622,7 @@
 		 */
 			new_blocks[index] = current_block;
 		}
-		blk_allocated += count;
+		blk_allocated += ar.len;
 	}
 allocated:
 	/* total number of blocks allocated for direct blocks */