static void au_do_dir_ts(void *arg)
{
struct au_dir_ts_arg *a = arg;
struct au_dtime dt;
struct path h_path;
struct inode *dir, *h_dir;
struct super_block *sb;
struct au_branch *br;
struct au_hinode *hdir;
int err;
aufs_bindex_t btop, bindex;
sb = a->dentry->d_sb;
if (d_really_is_negative(a->dentry))
goto out;
/* no dir->i_mutex lock */
aufs_read_lock(a->dentry, AuLock_DW); /* noflush */
dir = d_inode(a->dentry);
btop = au_ibtop(dir);
bindex = au_br_index(sb, a->brid);
if (bindex < btop)
goto out_unlock;
br = au_sbr(sb, bindex);
h_path.dentry = au_h_dptr(a->dentry, bindex);
if (!h_path.dentry)
goto out_unlock;
h_path.mnt = au_br_mnt(br);
au_dtime_store(&dt, a->dentry, &h_path);
br = au_sbr(sb, btop);
if (!au_br_writable(br->br_perm))
goto out_unlock;
h_path.dentry = au_h_dptr(a->dentry, btop);
h_path.mnt = au_br_mnt(br);
err = vfsub_mnt_want_write(h_path.mnt);
if (err)
goto out_unlock;
hdir = au_hi(dir, btop);
au_hn_inode_lock_nested(hdir, AuLsc_I_PARENT);
h_dir = au_h_iptr(dir, btop);
if (h_dir->i_nlink
&& timespec_compare(&h_dir->i_mtime, &dt.dt_mtime) < 0) {
dt.dt_h_path = h_path;
au_dtime_revert(&dt);
}
au_hn_inode_unlock(hdir);
vfsub_mnt_drop_write(h_path.mnt);
au_cpup_attr_timesizes(dir);
out_unlock:
aufs_read_unlock(a->dentry, AuLock_DW);
out:
dput(a->dentry);
au_nwt_done(&au_sbi(sb)->si_nowait);
kfree(arg);
}
/*
* locking order
* (VFS)
* - src_dir and dir by lock_rename()
* - inode if exitsts
* (aufs)
* - lock all
* + src_dentry and dentry by aufs_read_and_write_lock2() which calls,
* + si_read_lock
* + di_write_lock2_child()
* + di_write_lock_child()
* + ii_write_lock_child()
* + di_write_lock_child2()
* + ii_write_lock_child2()
* + src_parent and parent
* + di_write_lock_parent()
* + ii_write_lock_parent()
* + di_write_lock_parent2()
* + ii_write_lock_parent2()
* + lower src_dir and dir by vfsub_lock_rename()
* + verify the every relationships between child and parent. if any
* of them failed, unlock all and return -EBUSY.
*/
static void au_ren_unlock(struct au_ren_args *a)
{
struct super_block *sb;
sb = a->dst_dentry->d_sb;
if (au_ftest_ren(a->flags, MNT_WRITE))
vfsub_mnt_drop_write(a->br->br_mnt);
vfsub_unlock_rename(a->src_h_parent, a->src_hdir,
a->dst_h_parent, a->dst_hdir);
}
