elks-enhanced - XT-Emporium

File editor

/*
 *  linux/fs/devices.c
 *
 * (C) 1993 Matthias Urlichs -- collected common code and tables.
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 */

#include <linuxmt/types.h>
#include <linuxmt/fs.h>
#include <linuxmt/major.h>
#include <linuxmt/string.h>
#include <linuxmt/sched.h>
#include <linuxmt/stat.h>
#include <linuxmt/fcntl.h>
#include <linuxmt/errno.h>
#include <linuxmt/kernel.h>

/* minor number of first BIOSHD floppy, used for overlaying /dev/hd* -> /dev/cf* */
#include "../arch/i86/drivers/block/bioshd.h"   /* FIXME move bioshd.h to linuxmt/ */
#define FIRST_BIOSFD_MINOR  (DRIVE_FD0 << MINOR_SHIFT)  /* minor number of /dev/fd0 */


struct device_struct {
    struct file_operations *ds_fops;
};

/* No initializer to put it in the BSS section (zero'ed at loading) */
static struct device_struct chrdevs[MAX_CHRDEV];

/* No initializer to put it in the BSS section (zero'ed at loading) */
static struct device_struct blkdevs[MAX_BLKDEV];

struct file_operations *get_blkfops(unsigned int major)
{
    return (major >= MAX_BLKDEV) ? NULL : blkdevs[major].ds_fops;
}

int INITPROC register_chrdev(unsigned int major, const char *name,
    struct file_operations *fops)
{
    register struct device_struct *dev = &chrdevs[major];

    if (major >= MAX_CHRDEV) return -EINVAL;
    if (dev->ds_fops && (dev->ds_fops != fops)) return -EBUSY;
    dev->ds_fops = fops;
    return 0;
}

int INITPROC register_blkdev(unsigned int major, const char *name,
    struct file_operations *fops)
{
    register struct device_struct *dev = &blkdevs[major];

    if (major >= MAX_BLKDEV || (dev->ds_fops && dev->ds_fops != fops)) {
        printk("%s: can't register blkdev %d\n", name, major);
        return -EBUSY;
    }
    dev->ds_fops = fops;
    return 0;
}

/*
 * Called every time a block special file is opened
 */

static int blkdev_open(struct inode *inode, struct file *filp)
{
    register struct file_operations *fop;
    int i;

    i = MAJOR(inode->i_rdev);
#if defined(CONFIG_BLK_DEV_ATA_CF) && defined(CONFIG_ARCH_SOLO86)
    /* map /dev/hd* to /dev/cf*, but not /dev/fd0* */
    if (i == BIOSHD_MAJOR && MINOR(inode->i_rdev) < FIRST_BIOSFD_MINOR) {
        inode->i_rdev = MKDEV(ATHD_MAJOR, MINOR(inode->i_rdev));
        return blkdev_open(inode, filp);
    }
#endif
    if (i >= MAX_BLKDEV || !(fop = blkdevs[i].ds_fops)) return -ENODEV;
    filp->f_op = fop;
    return (fop->open) ? fop->open(inode, filp) : 0;
}

/*
 * Dummy default file-operations: the only thing this does
 * is contain the open that then fills in the correct operations
 * depending on the special file...
 */
struct file_operations def_blk_fops = {
    NULL,                       /* lseek */
    NULL,                       /* read */
    NULL,                       /* write */
    NULL,                       /* readdir */
    NULL,                       /* select */
    NULL,                       /* ioctl */
    blkdev_open,                /* open */
    NULL,                       /* release */
};

struct inode_operations blkdev_inode_operations = {
    &def_blk_fops,              /* default file operations */
    NULL,                       /* create */
    NULL,                       /* lookup */
    NULL,                       /* link */
    NULL,                       /* unlink */
    NULL,                       /* symlink */
    NULL,                       /* mkdir */
    NULL,                       /* rmdir */
    NULL,                       /* mknod */
    NULL,                       /* readlink */
    NULL,                       /* follow_link */
    NULL,                       /* getblk */
    NULL                        /* truncate */
};

/*
 * Called every time a character special file is opened.
 */

static int chrdev_open(struct inode *inode, struct file *filp)
{
    register struct file_operations *fop;
    int i;

    i = MAJOR(inode->i_rdev);
    if (i >= MAX_CHRDEV || !(fop = chrdevs[i].ds_fops)) return -ENODEV;
    filp->f_op = fop;
    return (fop->open) ? fop->open(inode, filp) : 0;
}

/*
 * Dummy default file-operations: the only thing this does
 * is contain the open that then fills in the correct operations
 * depending on the special file...
 */

struct file_operations def_chr_fops = {
    NULL,                       /* lseek */
    NULL,                       /* read */
    NULL,                       /* write */
    NULL,                       /* readdir */
    NULL,                       /* select */
    NULL,                       /* ioctl */
    chrdev_open,                /* open */
    NULL                        /* release */
};

struct inode_operations chrdev_inode_operations = {
    &def_chr_fops,              /* default file operations */
    NULL,                       /* create */
    NULL,                       /* lookup */
    NULL,                       /* link */
    NULL,                       /* unlink */
    NULL,                       /* symlink */
    NULL,                       /* mkdir */
    NULL,                       /* rmdir */
    NULL,                       /* mknod */
    NULL,                       /* readlink */
    NULL,                       /* follow_link */
    NULL,                       /* getblk */
    NULL                        /* truncate */
};
Commit message
This repository is read-only for this account.
Repository snapshot

Current branch
master
Visibility
public
Your access
Read
Remote
Configured
File activity

View file history