sr_ioctl.c

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

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

#if 0
#define DEBUG
#endif

/* 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

/* ATAPI drives don't have a SCMD_PLAYAUDIO_TI command.  When these drives
   are emulating a SCSI device via the idescsi module, they need to have
   CDROMPLAYTRKIND commands translated into CDROMPLAYMSF commands for them */

static int sr_fake_playtrkind(struct cdrom_device_info *cdi, struct cdrom_ti *ti)
{
	struct cdrom_tocentry trk0_te, trk1_te;
	struct cdrom_tochdr tochdr;
	u_char sr_cmd[10];
	int ntracks, ret;

	if ((ret = sr_audio_ioctl(cdi, CDROMREADTOCHDR, &tochdr)))
		return ret;

	ntracks = tochdr.cdth_trk1 - tochdr.cdth_trk0 + 1;
	
	if (ti->cdti_trk1 == ntracks) 
		ti->cdti_trk1 = CDROM_LEADOUT;
	else 
		ti->cdti_trk1 ++;

	trk0_te.cdte_track = ti->cdti_trk0;
	trk0_te.cdte_format = CDROM_MSF;
	trk1_te.cdte_track = ti->cdti_trk1;
	trk1_te.cdte_format = CDROM_MSF;
	
	if ((ret = sr_audio_ioctl(cdi, CDROMREADTOCENTRY, &trk0_te)))
		return ret;
	if ((ret = sr_audio_ioctl(cdi, CDROMREADTOCENTRY, &trk1_te)))
		return ret;
	
	sr_cmd[0] = GPCMD_PLAY_AUDIO_MSF;
	sr_cmd[3] = trk0_te.cdte_addr.msf.minute;
	sr_cmd[4] = trk0_te.cdte_addr.msf.second;
	sr_cmd[5] = trk0_te.cdte_addr.msf.frame;
	sr_cmd[6] = trk1_te.cdte_addr.msf.minute;
	sr_cmd[7] = trk1_te.cdte_addr.msf.second;
	sr_cmd[8] = trk1_te.cdte_addr.msf.frame;
	return sr_do_ioctl(MINOR(cdi->dev), sr_cmd, NULL, 0, 0, SCSI_DATA_NONE, NULL);
}

/* 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, int readwrite, struct request_sense *sense)
{
	Scsi_Request *SRpnt;
	Scsi_Device *SDev;
        struct request *req;
	int result, err = 0, retries = 0;
	char *bounce_buffer;

	SDev = scsi_CDs[target].device;
	SRpnt = scsi_allocate_request(scsi_CDs[target].device);
	SRpnt->sr_data_direction = readwrite;

	/* use ISA DMA buffer if necessary */
	SRpnt->sr_request.buffer = buffer;
	if (buffer && SRpnt->sr_host->unchecked_isa_dma &&
	    (virt_to_phys(buffer) + buflength - 1 > ISA_DMA_THRESHOLD)) {
		bounce_buffer = (char *) scsi_malloc((buflength + 511) & ~511);
		if (bounce_buffer == NULL) {
			printk("SCSI DMA pool exhausted.");
			return -ENOMEM;
		}
		memcpy(bounce_buffer, (char *) buffer, buflength);
		buffer = bounce_buffer;
	}
      retry:
	if (!scsi_block_when_processing_errors(SDev))
		return -ENODEV;


	scsi_wait_req(SRpnt, (void *) sr_cmd, (void *) buffer, buflength,
		      IOCTL_TIMEOUT, IOCTL_RETRIES);

	req = &SRpnt->sr_request;
	if (SRpnt->sr_buffer && req->buffer && SRpnt->sr_buffer != req->buffer) {
		memcpy(req->buffer, SRpnt->sr_buffer, SRpnt->sr_bufflen);
		scsi_free(SRpnt->sr_buffer, (SRpnt->sr_bufflen + 511) & ~511);
		SRpnt->sr_buffer = req->buffer;
        }

	result = SRpnt->sr_result;

	/* Minimal error checking.  Ignore cases we know about, and report the rest. */
	if (driver_byte(result) != 0) {
		switch (SRpnt->sr_sense_buffer[2] & 0xf) {
		case UNIT_ATTENTION:
			scsi_CDs[target].device->changed = 1;
			if (!quiet)
				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 (SRpnt->sr_sense_buffer[12] == 0x04 &&
			    SRpnt->sr_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 enough? */
					err = -ENOMEDIUM;
					break;
				}
			}
			if (!quiet)
				printk(KERN_INFO "sr%d: CDROM not ready.  Make sure there is a disc in the drive.\n", target);
#ifdef DEBUG
			print_req_sense("sr", SRpnt);
#endif
			err = -ENOMEDIUM;
			break;
		case ILLEGAL_REQUEST:
			if (!quiet)
				printk(KERN_ERR "sr%d: CDROM (ioctl) reports ILLEGAL "
				       "REQUEST.\n", target);
			if (SRpnt->sr_sense_buffer[12] == 0x20 &&
			    SRpnt->sr_sense_buffer[13] == 0x00) {
				/* sense: Invalid command operation code */
				err = -EDRIVE_CANT_DO_THIS;
			} else {
				err = -EINVAL;
			}
#ifdef DEBUG
			print_command(sr_cmd);
			print_req_sense("sr", SRpnt);
#endif
			break;
		default:
			printk(KERN_ERR "sr%d: CDROM (ioctl) error, command: ", target);
			print_command(sr_cmd);
			print_req_sense("sr", SRpnt);
			err = -EIO;
		}
	}

	if (sense)
		memcpy(sense, SRpnt->sr_sense_buffer, sizeof(*sense));

	/* Wake up a process waiting for device */
	scsi_release_request(SRpnt);
	SRpnt = NULL;
	return err;
}

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

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

	sr_cmd[0] = GPCMD_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, 0, 1, SCSI_DATA_NONE, NULL);
}

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

	sr_cmd[0] = GPCMD_START_STOP_UNIT;
	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, 0, 0, SCSI_DATA_NONE, NULL);
}

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[32];
	int result;

	sr_cmd[0] = GPCMD_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;