hfsplus: introduce alloc_mutex

Use a new per-sb alloc_mutex instead of abusing i_mutex of the alloc_file
to protect block allocations.  This gets rid of lockdep nesting warnings
and prepares for extending the scope of alloc_mutex.

Signed-off-by: Christoph Hellwig <hch@tuxera.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/fs/hfsplus/super.c b/fs/hfsplus/super.c
index 3b55c050c742..3dc62aa58728 100644
--- a/fs/hfsplus/super.c
+++ b/fs/hfsplus/super.c
@@ -321,6 +321,7 @@ static int hfsplus_fill_super(struct super_block *sb, void *data, int silent)
 
         sb->s_fs_info = sbi;
         INIT_HLIST_HEAD(&sbi->rsrc_inodes);
+        mutex_init(&sbi->alloc_mutex);
         hfsplus_fill_defaults(sbi);
         if (!hfsplus_parse_options(data, sbi)) {
                 printk(KERN_ERR "hfs: unable to parse mount options\n");