hfsplus: Fix undefined __divdi3 in hfsplus_init_header_node()

ERROR: "__divdi3" [fs/hfsplus/hfsplus.ko] undefined!

Introduced by commit 099e9245e04d ("hfsplus: implement attributes file's
header node initialization code").

i_size_read() returns loff_t, which is long long, i.e.  64-bit.  node_size
is size_t, which is either 32-bit or 64-bit.  Hence
"i_size_read(attr_file) / node_size" is a 64-by-32 or 64-by-64 division,
causing (some versions of) gcc to emit a call to __divdi3().

Fortunately node_size is actually 16-bit, as the sole caller of
hfsplus_init_header_node() passes a u16.  Hence change its type from
size_t to u16, and use do_div() to perform a 64-by-32 division.

Not seen in m68k/allmodconfig in -next, so it really depends on the
verion of gcc.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Vyacheslav Dubeyko <slava@dubeyko.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 6 insertions, 3 deletions

diff --git a/fs/hfsplus/xattr.c b/fs/hfsplus/xattr.c
index efc85b1377cc..3c6136f98c73 100644
--- a/fs/hfsplus/xattr.c
+++ b/fs/hfsplus/xattr.c
@@ -129,7 +129,7 @@ static int can_set_xattr(struct inode *inode, const char *name,
 
 static void hfsplus_init_header_node(struct inode *attr_file,
                                         u32 clump_size,
-                                        char *buf, size_t node_size)
+                                        char *buf, u16 node_size)
 {
         struct hfs_bnode_desc *desc;
         struct hfs_btree_header_rec *head;
@@ -139,8 +139,9 @@ static void hfsplus_init_header_node(struct inode *attr_file,
         char *bmp;
         u32 used_nodes;
         u32 used_bmp_bytes;
+        loff_t tmp;
 
-        hfs_dbg(ATTR_MOD, "init_hdr_attr_file: clump %u, node_size %zu\n",
+        hfs_dbg(ATTR_MOD, "init_hdr_attr_file: clump %u, node_size %u\n",
                                 clump_size, node_size);
 
         /* The end of the node contains list of record offsets */
@@ -154,7 +155,9 @@ static void hfsplus_init_header_node(struct inode *attr_file,
 
         head = (struct hfs_btree_header_rec *)(buf + offset);
         head->node_size = cpu_to_be16(node_size);
-        head->node_count = cpu_to_be32(i_size_read(attr_file) / node_size);
+        tmp = i_size_read(attr_file);
+        do_div(tmp, node_size);
+        head->node_count = cpu_to_be32(tmp);
         head->free_nodes = cpu_to_be32(be32_to_cpu(head->node_count) - 1);
         head->clump_size = cpu_to_be32(clump_size);
         head->attributes |= cpu_to_be32(HFS_TREE_BIGKEYS | HFS_TREE_VARIDXKEYS);