sd_ioctl.c

基于组件方式开发操作系统的OSKIT源代码

/*
 * drivers/scsi/sd_ioctl.c
 *
 * ioctl handling for SCSI disks
 */

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/hdreg.h>
#include <linux/errno.h>

#include <asm/uaccess.h>

#define MAJOR_NR	SCSI_DISK0_MAJOR
#include <linux/blk.h>
#include "scsi.h"
#include <scsi/scsi_ioctl.h>
#include "hosts.h"
#include "sd.h"
#include <scsi/scsicam.h>     /* must follow "hosts.h" */

int sd_ioctl(struct inode * inode, struct file * file, unsigned int cmd, unsigned long arg)
{
    kdev_t dev = inode->i_rdev;
    int error;
    struct Scsi_Host * host;
    Scsi_Device * SDev;
    int diskinfo[4];
    struct hd_geometry *loc = (struct hd_geometry *) arg;
    
    SDev = rscsi_disks[DEVICE_NR(dev)].device;
    /*
     * If we are in the middle of error recovery, don't let anyone
     * else try and use this device.  Also, if error recovery fails, it
     * may try and take the device offline, in which case all further
     * access to the device is prohibited.
     */
    if( !scsi_block_when_processing_errors(SDev) )
      {
        return -ENODEV;
      }

    switch (cmd) {
    case HDIO_GETGEO:   /* Return BIOS disk parameters */
	if (!loc)  return -EINVAL;
	error = verify_area(VERIFY_WRITE, loc, sizeof(*loc));
	if (error)
	    return error;
	host = rscsi_disks[DEVICE_NR(dev)].device->host;

/* default to most commonly used values */

        diskinfo[0] = 0x40;
        diskinfo[1] = 0x20;
        diskinfo[2] = rscsi_disks[DEVICE_NR(dev)].capacity >> 11;

/* override with calculated, extended default, or driver values */

	if(host->hostt->bios_param != NULL)
	    host->hostt->bios_param(&rscsi_disks[DEVICE_NR(dev)],
				    dev,
				    &diskinfo[0]);
        else scsicam_bios_param(&rscsi_disks[DEVICE_NR(dev)],
				dev, &diskinfo[0]);

	put_user(diskinfo[0], &loc->heads);
	put_user(diskinfo[1], &loc->sectors);
	put_user(diskinfo[2], &loc->cylinders);
	put_user(sd[SD_PARTITION(inode->i_rdev)].start_sect, &loc->start);
	return 0;
    case BLKGETSIZE:   /* Return device size */
	if (!arg)  return -EINVAL;
	error = verify_area(VERIFY_WRITE, (long *) arg, sizeof(long));
	if (error)
	    return error;
	put_user(sd[SD_PARTITION(inode->i_rdev)].nr_sects,
		 (long *) arg);
	return 0;

    case BLKRASET:
	if (!capable(CAP_SYS_ADMIN))
		return -EACCES;
	if(!(inode->i_rdev)) return -EINVAL;
	if(arg > 0xff) return -EINVAL;
	read_ahead[MAJOR(inode->i_rdev)] = arg;
	return 0;

    case BLKRAGET:
	if (!arg)
		return -EINVAL;
	error = verify_area(VERIFY_WRITE, (long *) arg, sizeof(long));
	if (error)
	    return error;
	put_user(read_ahead[MAJOR(inode->i_rdev)], (long *) arg);
	return 0;

    case BLKFLSBUF:
	if(!capable(CAP_SYS_ADMIN))  return -EACCES;
	if(!(inode->i_rdev)) return -EINVAL;
	fsync_dev(inode->i_rdev);
	invalidate_buffers(inode->i_rdev);
	return 0;
	
    case BLKRRPART: /* Re-read partition tables */
        if (!capable(CAP_SYS_ADMIN))
                return -EACCES;
	return revalidate_scsidisk(dev, 1);

    case BLKSSZGET:
	/* Block size of media */
	return put_user(blksize_size[MAJOR(dev)][MINOR(dev)&0x0F],
		(int *)arg);
				
    RO_IOCTLS(dev, arg);

    default:
	return scsi_ioctl(rscsi_disks[DEVICE_NR(dev)].device , cmd, (void *) arg);
    }
}

/*
 * Overrides for Emacs so that we follow Linus's tabbing style.
 * Emacs will notice this stuff at the end of the file and automatically
 * adjust the settings for this buffer only.  This must remain at the end
 * of the file.
 * ---------------------------------------------------------------------------
 * Local variables:
 * c-indent-level: 4
 * c-brace-imaginary-offset: 0
 * c-brace-offset: -4
 * c-argdecl-indent: 4
 * c-label-offset: -4
 * c-continued-statement-offset: 4
 * c-continued-brace-offset: 0
 * indent-tabs-mode: nil
 * tab-width: 8
 * End:
 */