int au_pin(struct au_pin *pin, struct dentry *dentry, aufs_bindex_t bindex,
unsigned int udba, unsigned char flags)
{
au_pin_init(pin, dentry, bindex, AuLsc_DI_PARENT, AuLsc_I_PARENT2,
udba, flags);
return au_do_pin(pin);
}
/* lock them all */
static int au_do_lock(const unsigned char dmsg, struct au_mvd_args *a)
{
int err;
struct dentry *h_trap;
a->mvd_h_src_sb = au_sbr_sb(a->sb, a->mvd_bsrc);
a->mvd_h_dst_sb = au_sbr_sb(a->sb, a->mvd_bdst);
err = au_pin(&a->mvd_pin_dst, a->dentry, a->mvd_bdst,
au_opt_udba(a->sb),
AuPin_MNT_WRITE | AuPin_DI_LOCKED);
AuTraceErr(err);
if (unlikely(err)) {
AU_MVD_PR(dmsg, "pin_dst failed\n");
goto out;
}
if (a->mvd_h_src_sb != a->mvd_h_dst_sb) {
a->rename_lock = 0;
au_pin_init(&a->mvd_pin_src, a->dentry, a->mvd_bsrc,
AuLsc_DI_PARENT, AuLsc_I_PARENT3,
au_opt_udba(a->sb),
AuPin_MNT_WRITE | AuPin_DI_LOCKED);
err = au_do_pin(&a->mvd_pin_src);
AuTraceErr(err);
a->mvd_h_src_dir = d_inode(a->mvd_h_src_parent);
if (unlikely(err)) {
AU_MVD_PR(dmsg, "pin_src failed\n");
goto out_dst;
}
goto out; /* success */
}
a->rename_lock = 1;
au_pin_hdir_unlock(&a->mvd_pin_dst);
err = au_pin(&a->mvd_pin_src, a->dentry, a->mvd_bsrc,
au_opt_udba(a->sb),
AuPin_MNT_WRITE | AuPin_DI_LOCKED);
AuTraceErr(err);
a->mvd_h_src_dir = d_inode(a->mvd_h_src_parent);
if (unlikely(err)) {
AU_MVD_PR(dmsg, "pin_src failed\n");
au_pin_hdir_lock(&a->mvd_pin_dst);
goto out_dst;
}
au_pin_hdir_unlock(&a->mvd_pin_src);
h_trap = vfsub_lock_rename(a->mvd_h_src_parent, a->mvd_hdir_src,
a->mvd_h_dst_parent, a->mvd_hdir_dst);
if (h_trap) {
err = (h_trap != a->mvd_h_src_parent);
if (err)
err = (h_trap != a->mvd_h_dst_parent);
}
BUG_ON(err); /* it should never happen */
if (unlikely(a->mvd_h_src_dir != au_pinned_h_dir(&a->mvd_pin_src))) {
err = -EBUSY;
AuTraceErr(err);
vfsub_unlock_rename(a->mvd_h_src_parent, a->mvd_hdir_src,
a->mvd_h_dst_parent, a->mvd_hdir_dst);
au_pin_hdir_lock(&a->mvd_pin_src);
au_unpin(&a->mvd_pin_src);
au_pin_hdir_lock(&a->mvd_pin_dst);
goto out_dst;
}
goto out; /* success */
out_dst:
au_unpin(&a->mvd_pin_dst);
out:
AuTraceErr(err);
return err;
}