内核新的ioctl方式--unlocked_ioctl和compat_ioctl(解决error:unknown field 'ioctl' specified in initializer)

LDD/problem/port/ioctl

1 问题

2.6.32

ioctl

2 原因

ioctl

file_operations

ioctl

file_operations

2.6.36

file_operations

file_operations

file_operations

ioctl

kernel 3.0

struct file_operations

ioctl

3 解决方案

ioctl

unlocked_ioctl

compat_ioctl

file_operations

unlocked_ioctl

compat_ioctl

ioctl()

struct inode*

ioctl

inode

inode

file_inode

file

inode

static inline struct inode *file_inode(const struct file *f)
{
return f->f_inode;
}

ioctl

unlock_ioctl

#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 36)
static int XXX_ioctl(
struct inode *indoe,
struct file *filp,
unsigned int cmd,
unsigned long arg)
{
#else
//long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
//long (*compat_ioctl) (struct file *, unsigned int cmd, unsigned long arg)
static long XXX_unlocked_ioctl(
struct file *filp,
unsigned int cmd,
unsigned long arg)
{
//struct inode *inode = filp->f_dentry->d_inode;
//struct inode *inode = filp->d_inode;
struct inode *inode = inode = file_inode(filp);
#endif
/*  此处是ioctl() 函数结构的具体实现  */
}

file_operations

static struct file_operations fpga_fops = {
.owner  = THIS_MODULE,
.open   = fpga_open,
.read   = fpga_read,
.write = fpga_write,
.llseek = fpga_llseek,
#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 36)
.ioctl = XXX_ioctl,
#else
.unlocked_ioctl = XXX_unlocked_ioctl,
#endif
};

4 参照