[PATCH 07/19] hypfs: use d_genocide to kill fs entries

[Christoph Hellwig]

hypfs is entirely synthetic and doesn't care about i_nlink when dropping
entries from the cache.  Switch to d_genocide instead of a home grown
file remove loop for unmount and write (yes, really!).

Signed-off-by: Christoph Hellwig <h...@lst.de>
---
 arch/s390/hypfs/inode.c | 37 ++-----------------------------------
 1 file changed, 2 insertions(+), 35 deletions(-)

diff --git a/arch/s390/hypfs/inode.c b/arch/s390/hypfs/inode.c
index dbe8a7dcafa922..3261fb9cade648 100644
--- a/arch/s390/hypfs/inode.c
+++ b/arch/s390/hypfs/inode.c
@@ -64,33 +64,6 @@ static void hypfs_add_dentry(struct dentry *dentry)
        hypfs_last_dentry = dentry;
 }
 
-static void hypfs_remove(struct dentry *dentry)
-{
-       struct dentry *parent;
-
-       parent = dentry->d_parent;
-       inode_lock(d_inode(parent));
-       if (simple_positive(dentry)) {
-               if (d_is_dir(dentry))
-                       simple_rmdir(d_inode(parent), dentry);
-               else
-                       simple_unlink(d_inode(parent), dentry);
-       }
-       d_drop(dentry);
-       dput(dentry);
-       inode_unlock(d_inode(parent));
-}
-
-static void hypfs_delete_tree(struct dentry *root)
-{
-       while (hypfs_last_dentry) {
-               struct dentry *next_dentry;
-               next_dentry = hypfs_last_dentry->d_fsdata;
-               hypfs_remove(hypfs_last_dentry);
-               hypfs_last_dentry = next_dentry;
-       }
-}
-
 static struct inode *hypfs_make_inode(struct super_block *sb, umode_t mode)
 {
        struct inode *ret = new_inode(sb);
@@ -183,14 +156,14 @@ static ssize_t hypfs_write_iter(struct kiocb *iocb, 
struct iov_iter *from)
                rc = -EBUSY;
                goto out;
        }
-       hypfs_delete_tree(sb->s_root);
+       d_genocide(sb->s_root);
        if (MACHINE_IS_VM)
                rc = hypfs_vm_create_files(sb->s_root);
        else
                rc = hypfs_diag_create_files(sb->s_root);
        if (rc) {
                pr_err("Updating the hypfs tree failed\n");
-               hypfs_delete_tree(sb->s_root);
+               d_genocide(sb->s_root);
                goto out;
        }
        hypfs_update_update(sb);
@@ -323,12 +296,6 @@ static int hypfs_init_fs_context(struct fs_context *fc)
 
 static void hypfs_kill_super(struct super_block *sb)
 {
-       struct hypfs_sb_info *sb_info = sb->s_fs_info;
-
-       if (sb->s_root)
-               hypfs_delete_tree(sb->s_root);
-       if (sb_info && sb_info->update_file)
-               hypfs_remove(sb_info->update_file);
        kill_litter_super(sb);
        kfree(sb->s_fs_info);
 }
-- 
2.39.2