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#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/fs.h>
#include <asm/uaccess.h>
#include <linux/errno.h>
#include <linux/string.h>

#include <linux/blk.h>
#include "scsi.h"
#include "hosts.h"
#include <scsi/scsi_ioctl.h>

#include <linux/cdrom.h>
#include "sr.h"

#if 0
# define DEBUG
#endif

/* for now we borrow the "operation not supported" from the network folks */
#define EDRIVE_CANT_DO_THIS  EOPNOTSUPP

/* The sr_is_xa() seems to trigger firmware bugs with some drives :-(
 * It is off by default and can be turned on with this module parameter */
static int xa_test = 0;

extern void get_sectorsize(int);

#define IOCTL_RETRIES 3
/* The CDROM is fairly slow, so we need a little extra time */
/* In fact, it is very slow if it has to spin up first */
#define IOCTL_TIMEOUT 30*HZ

static void sr_ioctl_done(Scsi_Cmnd * SCpnt)
{
    struct request * req;
    
    req = &SCpnt->request;
    req->rq_status = RQ_SCSI_DONE; /* Busy, but indicate request done */
    
    if (req->sem != NULL) {
	up(req->sem);
    }
}

/* We do our own retries because we want to know what the specific
   error code is.  Normally the UNIT_ATTENTION code will automatically
   clear after one error */

int sr_do_ioctl(int target, unsigned char * sr_cmd, void * buffer, unsigned buflength, int quiet)
{
    Scsi_Cmnd * SCpnt;
    Scsi_Device * SDev;
    int result, err = 0, retries = 0;

    SDev  = scsi_CDs[target].device;
    SCpnt = scsi_allocate_device(NULL, scsi_CDs[target].device, 1);

retry:
    if( !scsi_block_when_processing_errors(SDev) )
        return -ENODEV;
    {
	struct semaphore sem = MUTEX_LOCKED;
	SCpnt->request.sem = &sem;
	scsi_do_cmd(SCpnt,
		    (void *) sr_cmd, buffer, buflength, sr_ioctl_done, 
		    IOCTL_TIMEOUT, IOCTL_RETRIES);
	down(&sem);
        SCpnt->request.sem = NULL;
    }
    
    result = SCpnt->result;
    
    /* Minimal error checking.  Ignore cases we know about, and report the rest. */
    if(driver_byte(result) != 0) {
	switch(SCpnt->sense_buffer[2] & 0xf) {
	case UNIT_ATTENTION:
	    scsi_CDs[target].device->changed = 1;
	    printk(KERN_INFO "sr%d: disc change detected.\n", target);
	    if (retries++ < 10)
		goto retry;
	    err = -ENOMEDIUM;
	    break;
	case NOT_READY: /* This happens if there is no disc in drive */
            if (SCpnt->sense_buffer[12] == 0x04 &&
                SCpnt->sense_buffer[13] == 0x01) {
                /* sense: Logical unit is in process of becoming ready */
                if (!quiet)
                    printk(KERN_INFO "sr%d: CDROM not ready yet.\n", target);
		if (retries++ < 10) {
		    /* sleep 2 sec and try again */
		    scsi_sleep(2*HZ);
                    goto retry;
		} else {
		    /* 20 secs are enouth? */
		    err = -ENOMEDIUM;
		    break;
		}
            }
            printk(KERN_INFO "sr%d: CDROM not ready.  Make sure there is a disc in the drive.\n",target);
#ifdef DEBUG
            print_sense("sr", SCpnt);
#endif
            err = -ENOMEDIUM;
	    break;
	case ILLEGAL_REQUEST:
            if (!quiet)
                printk("sr%d: CDROM (ioctl) reports ILLEGAL REQUEST.\n",
                       target);
            if (SCpnt->sense_buffer[12] == 0x20 &&
                SCpnt->sense_buffer[13] == 0x00) {
                /* sense: Invalid command operation code */
                err = -EDRIVE_CANT_DO_THIS;
            } else {
                err = -EINVAL;
            }
#ifdef DEBUG
	    print_command(sr_cmd);
            print_sense("sr", SCpnt);
#endif
	    break;
	default:
	    printk("sr%d: CDROM (ioctl) error, command: ", target);
	    print_command(sr_cmd);
	    print_sense("sr", SCpnt);
            err = -EIO;
	}
    }
    
    result = SCpnt->result;
    /* Wake up a process waiting for device*/
    wake_up(&SCpnt->device->device_wait);
    scsi_release_command(SCpnt);
    SCpnt = NULL;
    return err;
}

/* ---------------------------------------------------------------------- */
/* interface to cdrom.c                                                   */

static int test_unit_ready(int minor)
{
	u_char  sr_cmd[10];

        sr_cmd[0] = TEST_UNIT_READY;
        sr_cmd[1] = ((scsi_CDs[minor].device -> lun) << 5);
        sr_cmd[2] = sr_cmd[3] = sr_cmd[4] = sr_cmd[5] = 0;
        return sr_do_ioctl(minor, sr_cmd, NULL, 255, 1);
}

int sr_tray_move(struct cdrom_device_info *cdi, int pos)
{
        u_char  sr_cmd[10];

        sr_cmd[0] = START_STOP;
        sr_cmd[1] = ((scsi_CDs[MINOR(cdi->dev)].device -> lun) << 5);
        sr_cmd[2] = sr_cmd[3] = sr_cmd[5] = 0;
        sr_cmd[4] = (pos == 0) ? 0x03 /* close */ : 0x02 /* eject */;
	
        return sr_do_ioctl(MINOR(cdi->dev), sr_cmd, NULL, 255, 0);
}

int sr_lock_door(struct cdrom_device_info *cdi, int lock)
{
        return scsi_ioctl (scsi_CDs[MINOR(cdi->dev)].device,
                           lock ? SCSI_IOCTL_DOORLOCK : SCSI_IOCTL_DOORUNLOCK,
                           0);
}

int sr_drive_status(struct cdrom_device_info *cdi, int slot)
{
        if (CDSL_CURRENT != slot) {
                /* we have no changer support */
                return -EINVAL;
        }

        if (0 == test_unit_ready(MINOR(cdi->dev)))
            return CDS_DISC_OK;

        return CDS_TRAY_OPEN;
}

int sr_disk_status(struct cdrom_device_info *cdi)
{
	struct cdrom_tochdr    toc_h;
	struct cdrom_tocentry  toc_e;
        int                    i,rc,have_datatracks = 0;

        /* look for data tracks */
        if (0 != (rc = sr_audio_ioctl(cdi, CDROMREADTOCHDR, &toc_h)))
                return (rc == -ENOMEDIUM) ? CDS_NO_DISC : CDS_NO_INFO;

        for (i = toc_h.cdth_trk0; i <= toc_h.cdth_trk1; i++) {
                toc_e.cdte_track  = i;
                toc_e.cdte_format = CDROM_LBA;
                if (sr_audio_ioctl(cdi, CDROMREADTOCENTRY, &toc_e))
                        return CDS_NO_INFO;
                if (toc_e.cdte_ctrl & CDROM_DATA_TRACK) {
                        have_datatracks = 1;
                        break;
                }
        }
        if (!have_datatracks)
            return CDS_AUDIO;

        if (scsi_CDs[MINOR(cdi->dev)].xa_flag)
            return CDS_XA_2_1;
        else
            return CDS_DATA_1;
}

int sr_get_last_session(struct cdrom_device_info *cdi,
                        struct cdrom_multisession* ms_info)
{
        ms_info->addr.lba=scsi_CDs[MINOR(cdi->dev)].ms_offset;
        ms_info->xa_flag=scsi_CDs[MINOR(cdi->dev)].xa_flag ||
            (scsi_CDs[MINOR(cdi->dev)].ms_offset > 0);

	return 0;
}

int sr_get_mcn(struct cdrom_device_info *cdi,struct cdrom_mcn *mcn)
{
        u_char  sr_cmd[10];
	char * buffer;
        int result;
        	
	sr_cmd[0] = SCMD_READ_SUBCHANNEL;
	sr_cmd[1] = ((scsi_CDs[MINOR(cdi->dev)].device->lun) << 5);
	sr_cmd[2] = 0x40;    /* I do want the subchannel info */
	sr_cmd[3] = 0x02;    /* Give me medium catalog number info */
	sr_cmd[4] = sr_cmd[5] = 0;
	sr_cmd[6] = 0;
	sr_cmd[7] = 0;
	sr_cmd[8] = 24;
	sr_cmd[9] = 0;
	
	buffer = (unsigned char*) scsi_malloc(512);
	if(!buffer) return -ENOMEM;
	
	result = sr_do_ioctl(MINOR(cdi->dev), sr_cmd, buffer, 24, 0);
	
	memcpy (mcn->medium_catalog_number, buffer + 9, 13);
        mcn->medium_catalog_number[13] = 0;

	scsi_free(buffer, 512);
	
	return result;
}

int sr_reset(struct cdrom_device_info *cdi)
{
	invalidate_buffers(cdi->dev);
	return 0;        
}

int sr_select_speed(struct cdrom_device_info *cdi, int speed)
{
        u_char  sr_cmd[12];

        if (speed == 0)
            speed = 0xffff; /* set to max */
        else
            speed *= 177;   /* Nx to kbyte/s */
        
	memset(sr_cmd,0,12);
	sr_cmd[0] = 0xbb; /* SET CD SPEED */
	sr_cmd[1] = (scsi_CDs[MINOR(cdi->dev)].device->lun) << 5;
	sr_cmd[2] = (speed >> 8) & 0xff; /* MSB for speed (in kbytes/sec) */
	sr_cmd[3] =  speed       & 0xff; /* LSB */

        if (sr_do_ioctl(MINOR(cdi->dev), sr_cmd, NULL, 0, 0))
            return -EIO;
	return 0;
}

/* ----------------------------------------------------------------------- */
/* this is called by the generic cdrom driver. arg is a _kernel_ pointer,  */
/* becauce the generic cdrom driver does the user access stuff for us.     */

int sr_audio_ioctl(struct cdrom_device_info *cdi, unsigned int cmd, void* arg)
{
    u_char  sr_cmd[10];    
    int result, target;
    
    target = MINOR(cdi->dev);
    
    switch (cmd) 
    {
	/* Sun-compatible */
    case CDROMPAUSE:
	
	sr_cmd[0] = SCMD_PAUSE_RESUME;
	sr_cmd[1] = scsi_CDs[target].device->lun << 5;
	sr_cmd[2] = sr_cmd[3] = sr_cmd[4] = 0;
	sr_cmd[5] = sr_cmd[6] = sr_cmd[7] = 0;
	sr_cmd[8] = 0;
	sr_cmd[9] = 0;
	
	result = sr_do_ioctl(target, sr_cmd, NULL, 255, 0);
        break;
	
    case CDROMRESUME:
	
	sr_cmd[0] = SCMD_PAUSE_RESUME;
	sr_cmd[1] = scsi_CDs[target].device->lun << 5;
	sr_cmd[2] = sr_cmd[3] = sr_cmd[4] = 0;
	sr_cmd[5] = sr_cmd[6] = sr_cmd[7] = 0;
	sr_cmd[8] = 1;
	sr_cmd[9] = 0;
	
	result = sr_do_ioctl(target, sr_cmd, NULL, 255, 0);
        break;
	
    case CDROMPLAYMSF:
    {
	struct cdrom_msf* msf = (struct cdrom_msf*)arg;

	sr_cmd[0] = SCMD_PLAYAUDIO_MSF;
	sr_cmd[1] = scsi_CDs[target].device->lun << 5;
	sr_cmd[2] = 0;
	sr_cmd[3] = msf->cdmsf_min0;
	sr_cmd[4] = msf->cdmsf_sec0;
	sr_cmd[5] = msf->cdmsf_frame0;
	sr_cmd[6] = msf->cdmsf_min1;
	sr_cmd[7] = msf->cdmsf_sec1;
	sr_cmd[8] = msf->cdmsf_frame1;
	sr_cmd[9] = 0;
	
	result = sr_do_ioctl(target, sr_cmd, NULL, 255, 0);
        break;
    }

    case CDROMPLAYBLK:
    {
	struct cdrom_blk* blk = (struct cdrom_blk*)arg;

	sr_cmd[0] = SCMD_PLAYAUDIO10;
	sr_cmd[1] = scsi_CDs[target].device->lun << 5;
	sr_cmd[2] = blk->from >> 24;
	sr_cmd[3] = blk->from >> 16;
	sr_cmd[4] = blk->from >> 8;
	sr_cmd[5] = blk->from;
	sr_cmd[6] = 0;
	sr_cmd[7] = blk->len >> 8;
	sr_cmd[8] = blk->len;
	sr_cmd[9] = 0;
	
	result = sr_do_ioctl(target, sr_cmd, NULL, 255, 0);
        break;
    }
		
    case CDROMPLAYTRKIND:
    {
	struct cdrom_ti* ti = (struct cdrom_ti*)arg;

	sr_cmd[0] = SCMD_PLAYAUDIO_TI;
	sr_cmd[1] = scsi_CDs[target].device->lun << 5;
	sr_cmd[2] = 0;
	sr_cmd[3] = 0;
	sr_cmd[4] = ti->cdti_trk0;
	sr_cmd[5] = ti->cdti_ind0;
	sr_cmd[6] = 0;
	sr_cmd[7] = ti->cdti_trk1;
	sr_cmd[8] = ti->cdti_ind1;
	sr_cmd[9] = 0;
	
	result = sr_do_ioctl(target, sr_cmd, NULL, 255, 0);
        break;
    }
	
    case CDROMREADTOCHDR:
    {
	struct cdrom_tochdr* tochdr = (struct cdrom_tochdr*)arg;
	char * buffer;
	
	sr_cmd[0] = SCMD_READ_TOC;
	sr_cmd[1] = ((scsi_CDs[target].device->lun) << 5);
	sr_cmd[2] = sr_cmd[3] = sr_cmd[4] = sr_cmd[5] = 0;
	sr_cmd[6] = 0;
	sr_cmd[7] = 0;              /* MSB of length (12) */
	sr_cmd[8] = 12;             /* LSB of length */
	sr_cmd[9] = 0;
	
	buffer = (unsigned char *) scsi_malloc(512);
	if(!buffer) return -ENOMEM;
	
	result = sr_do_ioctl(target, sr_cmd, buffer, 12, 0);
	
	tochdr->cdth_trk0 = buffer[2];
	tochdr->cdth_trk1 = buffer[3];
	
	scsi_free(buffer, 512);
        break;
    }
	
    case CDROMREADTOCENTRY:
    {
	struct cdrom_tocentry* tocentry = (struct cdrom_tocentry*)arg;
	unsigned char * buffer;
	
	sr_cmd[0] = SCMD_READ_TOC;
	sr_cmd[1] = ((scsi_CDs[target].device->lun) << 5) |
          (tocentry->cdte_format == CDROM_MSF ? 0x02 : 0);
	sr_cmd[2] = sr_cmd[3] = sr_cmd[4] = sr_cmd[5] = 0;
	sr_cmd[6] = tocentry->cdte_track;
	sr_cmd[7] = 0;             /* MSB of length (12)  */
	sr_cmd[8] = 12;            /* LSB of length */
	sr_cmd[9] = 0;
	
	buffer = (unsigned char *) scsi_malloc(512);
	if(!buffer) return -ENOMEM;
	
	result = sr_do_ioctl (target, sr_cmd, buffer, 12, 0);
	
        tocentry->cdte_ctrl = buffer[5] & 0xf;	
        tocentry->cdte_adr = buffer[5] >> 4;
        tocentry->cdte_datamode = (tocentry->cdte_ctrl & 0x04) ? 1 : 0;
	if (tocentry->cdte_format == CDROM_MSF) {
	    tocentry->cdte_addr.msf.minute = buffer[9];
	    tocentry->cdte_addr.msf.second = buffer[10];
	    tocentry->cdte_addr.msf.frame = buffer[11];
	} else
	    tocentry->cdte_addr.lba = (((((buffer[8] << 8) + buffer[9]) << 8)
                                       + buffer[10]) << 8) + buffer[11];
	
	scsi_free(buffer, 512);
        break;
    }
	
    case CDROMSTOP:
	sr_cmd[0] = START_STOP;
	sr_cmd[1] = ((scsi_CDs[target].device->lun) << 5) | 1;
	sr_cmd[2] = sr_cmd[3] = sr_cmd[5] = 0;
	sr_cmd[4] = 0;
	
	result = sr_do_ioctl(target, sr_cmd, NULL, 255, 0);
        break;
	
    case CDROMSTART:
	sr_cmd[0] = START_STOP;
	sr_cmd[1] = ((scsi_CDs[target].device->lun) << 5) | 1;
	sr_cmd[2] = sr_cmd[3] = sr_cmd[5] = 0;
	sr_cmd[4] = 1;
	
	result = sr_do_ioctl(target, sr_cmd, NULL, 255, 0);
        break;
	
    case CDROMVOLCTRL:
    {
	char * buffer, * mask;
	struct cdrom_volctrl* volctrl = (struct cdrom_volctrl*)arg;
	
	/* First we get the current params so we can just twiddle the volume */
	
	sr_cmd[0] = MODE_SENSE;
	sr_cmd[1] = (scsi_CDs[target].device -> lun) << 5;
	sr_cmd[2] = 0xe;    /* Want mode page 0xe, CDROM audio params */
	sr_cmd[3] = 0;
	sr_cmd[4] = 28;
	sr_cmd[5] = 0;
	
	buffer = (unsigned char *) scsi_malloc(512);
	if(!buffer) return -ENOMEM;
	
	if ((result = sr_do_ioctl (target, sr_cmd, buffer, 28, 0))) {
	    printk ("Hosed while obtaining audio mode page\n");
	    scsi_free(buffer, 512);
            break;
	}
	
	sr_cmd[0] = MODE_SENSE;
	sr_cmd[1] = (scsi_CDs[target].device -> lun) << 5;
	sr_cmd[2] = 0x4e;   /* Want the mask for mode page 0xe */
	sr_cmd[3] = 0;
	sr_cmd[4] = 28;
	sr_cmd[5] = 0;
	
	mask = (unsigned char *) scsi_malloc(512);
	if(!mask) {
	    scsi_free(buffer, 512);
	    result = -ENOMEM;
            break;
	};

	if ((result = sr_do_ioctl (target, sr_cmd, mask, 28, 0))) {
	    printk ("Hosed while obtaining mask for audio mode page\n");
	    scsi_free(buffer, 512);
	    scsi_free(mask, 512);
	    break;
	}
	
	/* Now mask and substitute our own volume and reuse the rest */
	buffer[0] = 0;  /* Clear reserved field */
	
	buffer[21] = volctrl->channel0 & mask[21];
	buffer[23] = volctrl->channel1 & mask[23];
	buffer[25] = volctrl->channel2 & mask[25];
	buffer[27] = volctrl->channel3 & mask[27];
	
	sr_cmd[0] = MODE_SELECT;
	sr_cmd[1] = ((scsi_CDs[target].device -> lun) << 5) | 0x10;    /* Params are SCSI-2 */
	sr_cmd[2] = sr_cmd[3] = 0;
	sr_cmd[4] = 28;
	sr_cmd[5] = 0;
	
	result = sr_do_ioctl (target, sr_cmd, buffer, 28, 0);
	scsi_free(buffer, 512);
	scsi_free(mask, 512);
        break;
    }
	
    case CDROMVOLREAD:
    {
	char * buffer;
	struct cdrom_volctrl* volctrl = (struct cdrom_volctrl*)arg;
	
	/* Get the current params */
	
	sr_cmd[0] = MODE_SENSE;
	sr_cmd[1] = (scsi_CDs[target].device -> lun) << 5;
	sr_cmd[2] = 0xe;    /* Want mode page 0xe, CDROM audio params */
	sr_cmd[3] = 0;
	sr_cmd[4] = 28;
	sr_cmd[5] = 0;
	
	buffer = (unsigned char *) scsi_malloc(512);
	if(!buffer) return -ENOMEM;
	
	if ((result = sr_do_ioctl (target, sr_cmd, buffer, 28, 0))) {
	    printk ("(CDROMVOLREAD) Hosed while obtaining audio mode page\n");
	    scsi_free(buffer, 512);
            break;
	}

	volctrl->channel0 = buffer[21];
	volctrl->channel1 = buffer[23];
	volctrl->channel2 = buffer[25];
	volctrl->channel3 = buffer[27];

	scsi_free(buffer, 512);
        break;
    }
	
    case CDROMSUBCHNL:
    {
	struct cdrom_subchnl* subchnl = (struct cdrom_subchnl*)arg;
	char * buffer;
	
	sr_cmd[0] = SCMD_READ_SUBCHANNEL;
	sr_cmd[1] = ((scsi_CDs[target].device->lun) << 5) | 0x02;    /* MSF format */
	sr_cmd[2] = 0x40;    /* I do want the subchannel info */
	sr_cmd[3] = 0x01;    /* Give me current position info */
	sr_cmd[4] = sr_cmd[5] = 0;
	sr_cmd[6] = 0;
	sr_cmd[7] = 0;
	sr_cmd[8] = 16;
	sr_cmd[9] = 0;
	
	buffer = (unsigned char*) scsi_malloc(512);
	if(!buffer) return -ENOMEM;
	
	result = sr_do_ioctl(target, sr_cmd, buffer, 16, 0);
	
	subchnl->cdsc_audiostatus = buffer[1];
	subchnl->cdsc_format = CDROM_MSF;
	subchnl->cdsc_ctrl = buffer[5] & 0xf;
	subchnl->cdsc_trk = buffer[6];
	subchnl->cdsc_ind = buffer[7];
	
	subchnl->cdsc_reladdr.msf.minute = buffer[13];
	subchnl->cdsc_reladdr.msf.second = buffer[14];
	subchnl->cdsc_reladdr.msf.frame = buffer[15];
	subchnl->cdsc_absaddr.msf.minute = buffer[9];
	subchnl->cdsc_absaddr.msf.second = buffer[10];
	subchnl->cdsc_absaddr.msf.frame = buffer[11];
	
	scsi_free(buffer, 512);
        break;
    }
    default:
        return -EINVAL;
    }

#if 0
    if (result)
        printk("DEBUG: sr_audio: result for ioctl %x: %x\n",cmd,result);
#endif
    
    return result;
}

/* -----------------------------------------------------------------------
 * a function to read all sorts of funny cdrom sectors using the READ_CD
 * scsi-3 mmc command
 *
 * lba:     linear block address
 * format:  0 = data (anything)
 *          1 = audio
 *          2 = data (mode 1)
 *          3 = data (mode 2)
 *          4 = data (mode 2 form1)
 *          5 = data (mode 2 form2)
 * blksize: 2048 | 2336 | 2340 | 2352
 */

int
sr_read_cd(int minor, unsigned char *dest, int lba, int format, int blksize)
{
    unsigned char  cmd[12];

#ifdef DEBUG
    printk("sr%d: sr_read_cd lba=%d format=%d blksize=%d\n",
           minor,lba,format,blksize);
#endif

    memset(cmd,0,12);
    cmd[0] = 0xbe /* READ_CD */;
    cmd[1] = (scsi_CDs[minor].device->lun << 5) | ((format & 7) << 2);
    cmd[2] = (unsigned char)(lba >> 24) & 0xff;
    cmd[3] = (unsigned char)(lba >> 16) & 0xff;
    cmd[4] = (unsigned char)(lba >>  8) & 0xff;
    cmd[5] = (unsigned char) lba        & 0xff;
    cmd[8] = 1;
    switch (blksize) {
    case 2336: cmd[9] = 0x58; break;
    case 2340: cmd[9] = 0x78; break;
    case 2352: cmd[9] = 0xf8; break;
    default:   cmd[9] = 0x10; break;
    }
    return sr_do_ioctl(minor, cmd, dest, blksize, 0);
}

/*
 * read sectors with blocksizes other than 2048
 */

int
sr_read_sector(int minor, int lba, int blksize, unsigned char *dest)
{
    unsigned char   cmd[12];    /* the scsi-command */
    int             rc;

    /* we try the READ CD command first... */
    if (scsi_CDs[minor].readcd_known) {
        rc = sr_read_cd(minor, dest, lba, 0, blksize);
        if (-EDRIVE_CANT_DO_THIS != rc)
            return rc;
        scsi_CDs[minor].readcd_known = 0;
        printk("CDROM does'nt support READ CD (0xbe) command\n");
        /* fall & retry the other way */
    }

    /* ... if this fails, we switch the blocksize using MODE SELECT */
    if (blksize != scsi_CDs[minor].sector_size)
        if (0 != (rc = sr_set_blocklength(minor, blksize)))
            return rc;

#ifdef DEBUG
    printk("sr%d: sr_read_sector lba=%d blksize=%d\n",minor,lba,blksize);
#endif
    
    memset(cmd,0,12);
    cmd[0] = READ_10;
    cmd[1] = (scsi_CDs[minor].device->lun << 5);
    cmd[2] = (unsigned char)(lba >> 24) & 0xff;
    cmd[3] = (unsigned char)(lba >> 16) & 0xff;
    cmd[4] = (unsigned char)(lba >>  8) & 0xff;
    cmd[5] = (unsigned char) lba        & 0xff;
    cmd[8] = 1;
    rc = sr_do_ioctl(minor, cmd, dest, blksize, 0);
    
    return rc;
}

/*
 * read a sector in raw mode to check the sector format
 * ret: 1 == mode2 (XA), 0 == mode1, <0 == error 
 */

int
sr_is_xa(int minor)
{
    unsigned char *raw_sector;
    int is_xa;
    
    if (!xa_test)
        return 0;
    
    raw_sector = (unsigned char *) scsi_malloc(2048+512);
    if (!raw_sector) return -ENOMEM;
    if (0 == sr_read_sector(minor,scsi_CDs[minor].ms_offset+16,
                            CD_FRAMESIZE_RAW1,raw_sector)) {
        is_xa = (raw_sector[3] == 0x02) ? 1 : 0;
    } else {
        /* read a raw sector failed for some reason. */
        is_xa = -1;
    }
    scsi_free(raw_sector, 2048+512);
#ifdef DEBUG
    printk("sr%d: sr_is_xa: %d\n",minor,is_xa);
#endif
    return is_xa;
}

int sr_dev_ioctl(struct cdrom_device_info *cdi,
                 unsigned int cmd, unsigned long arg)
{
    int target, err;
    
    target = MINOR(cdi->dev);
    
    switch (cmd) {
    case CDROMREADMODE1:
    case CDROMREADMODE2:
    case CDROMREADRAW:
    {
	unsigned char      *raw;
        struct cdrom_msf   msf;
        int                lba, rc;
	int                blocksize = 2048;

        switch (cmd) {
        case CDROMREADMODE2: blocksize = CD_FRAMESIZE_RAW0; break; /* 2336 */
        case CDROMREADRAW:   blocksize = CD_FRAMESIZE_RAW;  break; /* 2352 */
        }

	if (copy_from_user(&msf,(void*)arg,sizeof(msf)))
		return -EFAULT;
	if (!(raw = scsi_malloc(2048+512)))
                return -ENOMEM;

	lba = (((msf.cdmsf_min0 * CD_SECS) + msf.cdmsf_sec0)
			* CD_FRAMES + msf.cdmsf_frame0) - CD_MSF_OFFSET;
        if (lba < 0 || lba >= scsi_CDs[target].capacity)
            return -EINVAL;

        rc = sr_read_sector(target, lba, blocksize, raw);
	if (!rc)
		if (copy_to_user((void*)arg, raw, blocksize))
			rc = -EFAULT;

	scsi_free(raw,2048+512);
	return rc;
    }
    case CDROMREADAUDIO:
    {
	unsigned char      *raw;
        int                lba, rc=0;
        struct cdrom_read_audio ra;

        if (!scsi_CDs[target].readcd_known || !scsi_CDs[target].readcd_cdda)
            return -EINVAL;  /* -EDRIVE_DOES_NOT_SUPPORT_THIS ? */
        
	if (copy_from_user(&ra,(void*)arg,sizeof(ra)))
            return -EFAULT;
        
        if (ra.addr_format == CDROM_LBA)
            lba = ra.addr.lba;
        else
            lba = (((ra.addr.msf.minute * CD_SECS) + ra.addr.msf.second)
                   * CD_FRAMES + ra.addr.msf.frame) - CD_MSF_OFFSET;

        if (lba < 0 || lba >= scsi_CDs[target].capacity)
            return -EINVAL;
	if (!(raw = scsi_malloc(2048+512)))
            return -ENOMEM;

        while (ra.nframes > 0) {
            rc = sr_read_cd(target, raw, lba, 1, CD_FRAMESIZE_RAW);
            if (!rc)
		if (copy_to_user(ra.buf, raw, CD_FRAMESIZE_RAW))
                    rc = -EFAULT;
            if (rc)
                break;

            ra.buf     += CD_FRAMESIZE_RAW;
            ra.nframes -= 1;
            lba++;
        }
	scsi_free(raw,2048+512);
        return rc;
    }
    case BLKRAGET:
	if (!arg)
		return -EINVAL;
	err = verify_area(VERIFY_WRITE, (long *) arg, sizeof(long));
	if (err)
		return err;
	put_user(read_ahead[MAJOR(cdi->dev)], (long *) arg);
	return 0;

    case BLKRASET:
	if(!suser())
        	return -EACCES;
	if(!(cdi->dev))
        	return -EINVAL;
	if(arg > 0xff)
        	return -EINVAL;
	read_ahead[MAJOR(cdi->dev)] = arg;
	return 0;

    RO_IOCTLS(cdi->dev,arg);

    default:
	return scsi_ioctl(scsi_CDs[target].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:
 */