fs: dcache per-inode inode alias locking

dcache_inode_lock can be replaced with per-inode locking. Use existing
inode->i_lock for this. This is slightly non-trivial because we sometimes
need to find the inode from the dentry, which requires d_inode to be
stabilised (either with refcount or d_lock).

Signed-off-by: Nick Piggin <npiggin@kernel.dk>

1 files changed, 2 insertions, 2 deletions

diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index df8bbb358d54..59782981b225 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -277,11 +277,11 @@ static struct dentry *v9fs_dentry_from_dir_inode(struct inode *inode)
 {
         struct dentry *dentry;
 
-        spin_lock(&dcache_inode_lock);
+        spin_lock(&inode->i_lock);
         /* Directory should have only one entry. */
         BUG_ON(S_ISDIR(inode->i_mode) && !list_is_singular(&inode->i_dentry));
         dentry = list_entry(inode->i_dentry.next, struct dentry, d_alias);
-        spin_unlock(&dcache_inode_lock);
+        spin_unlock(&inode->i_lock);
         return dentry;
 }