Subversion Repositories test_project

/*

 * /dev/nvram driver for Power Macintosh.

 */

#define NVRAM_VERSION "1.0"

#include <linux/module.h>

#include <linux/types.h>

#include <linux/errno.h>

#include <linux/fs.h>

#include <linux/miscdevice.h>

#include <linux/fcntl.h>

#include <linux/nvram.h>

#include <linux/init.h>

#include <linux/smp_lock.h>

#include <asm/uaccess.h>

#include <asm/nvram.h>

#define NVRAM_SIZE      8192

static loff_t nvram_llseek(struct file *file, loff_t offset, int origin)

{

        lock_kernel();

        switch (origin) {

        case 1:

                offset += file->f_pos;

                break;

        case 2:

                offset += NVRAM_SIZE;

                break;

        }

        if (offset < 0) {

                unlock_kernel();

                return -EINVAL;

        }

        file->f_pos = offset;

        unlock_kernel();

        return file->f_pos;

}

static ssize_t read_nvram(struct file *file, char __user *buf,

                          size_t count, loff_t *ppos)

{

        unsigned int i;

        char __user *p = buf;

        if (!access_ok(VERIFY_WRITE, buf, count))

                return -EFAULT;

        if (*ppos >= NVRAM_SIZE)

                return 0;

        for (i = *ppos; count > 0 && i < NVRAM_SIZE; ++i, ++p, --count)

                if (__put_user(nvram_read_byte(i), p))

                        return -EFAULT;

        *ppos = i;

        return p - buf;

}

static ssize_t write_nvram(struct file *file, const char __user *buf,

                           size_t count, loff_t *ppos)

{

        unsigned int i;

        const char __user *p = buf;

        char c;

        if (!access_ok(VERIFY_READ, buf, count))

                return -EFAULT;

        if (*ppos >= NVRAM_SIZE)

                return 0;

        for (i = *ppos; count > 0 && i < NVRAM_SIZE; ++i, ++p, --count) {

                if (__get_user(c, p))

                        return -EFAULT;

                nvram_write_byte(c, i);

        }

        *ppos = i;

        return p - buf;

}

static int nvram_ioctl(struct inode *inode, struct file *file,

        unsigned int cmd, unsigned long arg)

{

        switch(cmd) {

                case PMAC_NVRAM_GET_OFFSET:

                {

                        int part, offset;

                        if (copy_from_user(&part, (void __user*)arg, sizeof(part)) != 0)

                                return -EFAULT;

                        if (part < pmac_nvram_OF || part > pmac_nvram_NR)

                                return -EINVAL;

                        offset = pmac_get_partition(part);

                        if (copy_to_user((void __user*)arg, &offset, sizeof(offset)) != 0)

                                return -EFAULT;

                        break;

                }

                default:

                        return -EINVAL;

        }

        return 0;

}

const struct file_operations nvram_fops = {

        .owner          = THIS_MODULE,

        .llseek         = nvram_llseek,

        .read           = read_nvram,

        .write          = write_nvram,

        .ioctl          = nvram_ioctl,

};

static struct miscdevice nvram_dev = {

        NVRAM_MINOR,

        "nvram",

        &nvram_fops

};

int __init nvram_init(void)

{

        printk(KERN_INFO "Macintosh non-volatile memory driver v%s\n",

                NVRAM_VERSION);

        return misc_register(&nvram_dev);

}

void __exit nvram_cleanup(void)

{

        misc_deregister( &nvram_dev );

}

module_init(nvram_init);

module_exit(nvram_cleanup);

MODULE_LICENSE("GPL");