Difference between ioctl and unlock_ioctl

I spent a lot of time debugging a program today and found that the cmd parameter of the application's ioctl passed to the driver's ioctl changed. According to "Linux Device Driver", this cmd should remain unchanged. Because the ioctl function pointer in struct file_operations has been completely deleted in kernel 2.6.36 and replaced by unlocked_ioctl, I doubt whether the two are compatible. I checked some information online, and many articles only talked about it in general, saying that ioctl in the application is compatible and does not need to be changed. The biggest impact of the change of this pointer function in the driver is that inode is missing in the parameter, so the application ioctl is compatible, but our ioctl function in the driver must be changed, otherwise the cmd parameter will change:

Original driver

static const struct file_operations globalmem_fops=
{
.owner=THIS_MODULE,
.llseek=globalmem_llseek,
.open=globalmem_open,
.read=globalmem_read,
.write=globalmem_write,
.ioctl=globalmem_ioctl,
.release=globalmem_release,
};

int globalmem_ioctl(struct inode* inode,struct file* filp, unsigned int cmd, unsigned long arg)

{

switch (cmd)

{

case:XXX: ...

…

}

}

After the change

static const struct file_operations globalmem_fops=
{
.owner=THIS_MODULE,
.llseek=globalmem_llseek,
.open=globalmem_open,
.read=globalmem_read,
.write=globalmem_write,
.unlocked_ioctl=globalmem_ioctl,
.release=globalmem_release,
};

int globalmem_ioctl(struct file* filp, unsigned int cmd, unsigned long arg) //No inode parameter!

{

switch (cmd)

{

case:XXX: ...

…

}

}