/*
* create the new device/file/directory - use copyup_permission to copyup
* times, and mode
*
* if the object being copied up is a regular file, the file is only created,
* the contents have to be copied up separately
*/
static int __copyup_ndentry(struct dentry *old_lower_dentry,
struct dentry *new_lower_dentry,
struct dentry *new_lower_parent_dentry,
char *symbuf)
{
int err = 0;
umode_t old_mode = old_lower_dentry->d_inode->i_mode;
struct sioq_args args;
if (S_ISDIR(old_mode)) {
args.mkdir.parent = new_lower_parent_dentry->d_inode;
args.mkdir.dentry = new_lower_dentry;
args.mkdir.mode = old_mode;
run_sioq(__unionfs_mkdir, &args);
err = args.err;
} else if (S_ISLNK(old_mode)) {
args.symlink.parent = new_lower_parent_dentry->d_inode;
args.symlink.dentry = new_lower_dentry;
args.symlink.symbuf = symbuf;
run_sioq(__unionfs_symlink, &args);
err = args.err;
} else if (S_ISBLK(old_mode) || S_ISCHR(old_mode) ||
S_ISFIFO(old_mode) || S_ISSOCK(old_mode)) {
args.mknod.parent = new_lower_parent_dentry->d_inode;
args.mknod.dentry = new_lower_dentry;
args.mknod.mode = old_mode;
args.mknod.dev = old_lower_dentry->d_inode->i_rdev;
run_sioq(__unionfs_mknod, &args);
err = args.err;
} else if (S_ISREG(old_mode)) {
struct nameidata nd;
err = init_lower_nd(&nd, LOOKUP_CREATE);
if (unlikely(err < 0))
goto out;
args.create.nd = &nd;
args.create.parent = new_lower_parent_dentry->d_inode;
args.create.dentry = new_lower_dentry;
args.create.mode = old_mode;
run_sioq(__unionfs_create, &args);
err = args.err;
release_lower_nd(&nd, err);
} else {
printk(KERN_CRIT "unionfs: unknown inode type %d\n",
old_mode);
BUG();
}
out:
return err;
}
static int unionfs_create(struct inode *dir, struct dentry *dentry,
int mode, struct nameidata *nd_unused)
{
int err = 0;
struct dentry *lower_dentry = NULL;
struct dentry *lower_parent_dentry = NULL;
struct dentry *parent;
int valid = 0;
struct nameidata lower_nd;
unionfs_read_lock(dentry->d_sb, UNIONFS_SMUTEX_CHILD);
parent = unionfs_lock_parent(dentry, UNIONFS_DMUTEX_PARENT);
unionfs_lock_dentry(dentry, UNIONFS_DMUTEX_CHILD);
valid = __unionfs_d_revalidate(dentry, parent, false);
if (unlikely(!valid)) {
err = -ESTALE; /* same as what real_lookup does */
goto out;
}
lower_dentry = find_writeable_branch(dir, dentry);
if (IS_ERR(lower_dentry)) {
err = PTR_ERR(lower_dentry);
goto out;
}
lower_parent_dentry = lock_parent(lower_dentry);
if (IS_ERR(lower_parent_dentry)) {
err = PTR_ERR(lower_parent_dentry);
goto out_unlock;
}
err = init_lower_nd(&lower_nd, LOOKUP_CREATE);
if (unlikely(err < 0))
goto out_unlock;
err = vfs_create(lower_parent_dentry->d_inode, lower_dentry, mode,
&lower_nd);
release_lower_nd(&lower_nd, err);
if (!err) {
err = PTR_ERR(unionfs_interpose(dentry, dir->i_sb, 0));
if (!err) {
unionfs_copy_attr_times(dir);
fsstack_copy_inode_size(dir,
lower_parent_dentry->d_inode);
/* update no. of links on parent directory */
dir->i_nlink = unionfs_get_nlinks(dir);
}
}
out_unlock:
unlock_dir(lower_parent_dentry);
out:
if (!err) {
unionfs_postcopyup_setmnt(dentry);
unionfs_check_inode(dir);
unionfs_check_dentry(dentry);
}
unionfs_unlock_dentry(dentry);
unionfs_unlock_parent(dentry, parent);
unionfs_read_unlock(dentry->d_sb);
return err;
}