st.c

linux和2410结合开发 用他可以生成2410所需的zImage文件

			STps->drv_block = 0;
			if (STps->drv_file >= 0)
				STps->drv_file++;
		} else if (STps->eof == ST_EOD_2)
			STps->eof = ST_EOD;
	} else if (STps->eof == ST_FM)
		STps->eof = ST_NOEOF;
	retval = total;

 out:
	if (SRpnt != NULL) {
		scsi_release_request(SRpnt);
		SRpnt = NULL;
	}
	up(&STp->lock);

	return retval;
}



/* Set the driver options */
static void st_log_options(Scsi_Tape * STp, ST_mode * STm, int dev)
{
	printk(KERN_INFO
	       "st%d: Mode %d options: buffer writes: %d, async writes: %d, read ahead: %d\n",
	       dev, STp->current_mode, STm->do_buffer_writes, STm->do_async_writes,
	       STm->do_read_ahead);
	printk(KERN_INFO
	       "st%d:    can bsr: %d, two FMs: %d, fast mteom: %d, auto lock: %d,\n",
	       dev, STp->can_bsr, STp->two_fm, STp->fast_mteom, STp->do_auto_lock);
	printk(KERN_INFO
	       "st%d:    defs for wr: %d, no block limits: %d, partitions: %d, s2 log: %d\n",
	       dev, STm->defaults_for_writes, STp->omit_blklims, STp->can_partitions,
	       STp->scsi2_logical);
	printk(KERN_INFO
	       "st%d:    sysv: %d nowait: %d\n", dev, STm->sysv, STp->immediate);
        DEB(printk(KERN_INFO
                   "st%d:    debugging: %d\n",
                   dev, debugging);)
}


static int st_set_options(Scsi_Tape *STp, long options)
{
	int value;
	long code;
	ST_mode *STm;
	int dev = TAPE_NR(STp->devt);

	STm = &(STp->modes[STp->current_mode]);
	if (!STm->defined) {
		memcpy(STm, &(STp->modes[0]), sizeof(ST_mode));
		modes_defined = TRUE;
                DEBC(printk(ST_DEB_MSG
                            "st%d: Initialized mode %d definition from mode 0\n",
                            dev, STp->current_mode));
	}

	code = options & MT_ST_OPTIONS;
	if (code == MT_ST_BOOLEANS) {
		STm->do_buffer_writes = (options & MT_ST_BUFFER_WRITES) != 0;
		STm->do_async_writes = (options & MT_ST_ASYNC_WRITES) != 0;
		STm->defaults_for_writes = (options & MT_ST_DEF_WRITES) != 0;
		STm->do_read_ahead = (options & MT_ST_READ_AHEAD) != 0;
		STp->two_fm = (options & MT_ST_TWO_FM) != 0;
		STp->fast_mteom = (options & MT_ST_FAST_MTEOM) != 0;
		STp->do_auto_lock = (options & MT_ST_AUTO_LOCK) != 0;
		STp->can_bsr = (options & MT_ST_CAN_BSR) != 0;
		STp->omit_blklims = (options & MT_ST_NO_BLKLIMS) != 0;
		if ((STp->device)->scsi_level >= SCSI_2)
			STp->can_partitions = (options & MT_ST_CAN_PARTITIONS) != 0;
		STp->scsi2_logical = (options & MT_ST_SCSI2LOGICAL) != 0;
		STp->immediate = (options & MT_ST_NOWAIT) != 0;
		STm->sysv = (options & MT_ST_SYSV) != 0;
		DEB( debugging = (options & MT_ST_DEBUGGING) != 0; )
		st_log_options(STp, STm, dev);
	} else if (code == MT_ST_SETBOOLEANS || code == MT_ST_CLEARBOOLEANS) {
		value = (code == MT_ST_SETBOOLEANS);
		if ((options & MT_ST_BUFFER_WRITES) != 0)
			STm->do_buffer_writes = value;
		if ((options & MT_ST_ASYNC_WRITES) != 0)
			STm->do_async_writes = value;
		if ((options & MT_ST_DEF_WRITES) != 0)
			STm->defaults_for_writes = value;
		if ((options & MT_ST_READ_AHEAD) != 0)
			STm->do_read_ahead = value;
		if ((options & MT_ST_TWO_FM) != 0)
			STp->two_fm = value;
		if ((options & MT_ST_FAST_MTEOM) != 0)
			STp->fast_mteom = value;
		if ((options & MT_ST_AUTO_LOCK) != 0)
			STp->do_auto_lock = value;
		if ((options & MT_ST_CAN_BSR) != 0)
			STp->can_bsr = value;
		if ((options & MT_ST_NO_BLKLIMS) != 0)
			STp->omit_blklims = value;
		if ((STp->device)->scsi_level >= SCSI_2 &&
		    (options & MT_ST_CAN_PARTITIONS) != 0)
			STp->can_partitions = value;
		if ((options & MT_ST_SCSI2LOGICAL) != 0)
			STp->scsi2_logical = value;
		if ((options & MT_ST_NOWAIT) != 0)
			STp->immediate = value;
		if ((options & MT_ST_SYSV) != 0)
			STm->sysv = value;
                DEB(
		if ((options & MT_ST_DEBUGGING) != 0)
			debugging = value; )
		st_log_options(STp, STm, dev);
	} else if (code == MT_ST_WRITE_THRESHOLD) {
		value = (options & ~MT_ST_OPTIONS) * ST_KILOBYTE;
		if (value < 1 || value > st_buffer_size) {
			printk(KERN_WARNING
                               "st%d: Write threshold %d too small or too large.\n",
			       dev, value);
			return (-EIO);
		}
		STp->write_threshold = value;
		printk(KERN_INFO "st%d: Write threshold set to %d bytes.\n",
		       dev, value);
	} else if (code == MT_ST_DEF_BLKSIZE) {
		value = (options & ~MT_ST_OPTIONS);
		if (value == ~MT_ST_OPTIONS) {
			STm->default_blksize = (-1);
			printk(KERN_INFO "st%d: Default block size disabled.\n", dev);
		} else {
			STm->default_blksize = value;
			printk(KERN_INFO "st%d: Default block size set to %d bytes.\n",
			       dev, STm->default_blksize);
			if (STp->ready == ST_READY) {
				STp->blksize_changed = FALSE;
				set_mode_densblk(STp, STm);
			}
		}
	} else if (code == MT_ST_TIMEOUTS) {
		value = (options & ~MT_ST_OPTIONS);
		if ((value & MT_ST_SET_LONG_TIMEOUT) != 0) {
			STp->long_timeout = (value & ~MT_ST_SET_LONG_TIMEOUT) * HZ;
			printk(KERN_INFO "st%d: Long timeout set to %d seconds.\n", dev,
			       (value & ~MT_ST_SET_LONG_TIMEOUT));
		} else {
			STp->timeout = value * HZ;
			printk(KERN_INFO "st%d: Normal timeout set to %d seconds.\n",
                               dev, value);
		}
	} else if (code == MT_ST_SET_CLN) {
		value = (options & ~MT_ST_OPTIONS) & 0xff;
		if (value != 0 &&
		    value < EXTENDED_SENSE_START && value >= SCSI_SENSE_BUFFERSIZE)
			return (-EINVAL);
		STp->cln_mode = value;
		STp->cln_sense_mask = (options >> 8) & 0xff;
		STp->cln_sense_value = (options >> 16) & 0xff;
		printk(KERN_INFO
		       "st%d: Cleaning request mode %d, mask %02x, value %02x\n",
		       dev, value, STp->cln_sense_mask, STp->cln_sense_value);
	} else if (code == MT_ST_DEF_OPTIONS) {
		code = (options & ~MT_ST_CLEAR_DEFAULT);
		value = (options & MT_ST_CLEAR_DEFAULT);
		if (code == MT_ST_DEF_DENSITY) {
			if (value == MT_ST_CLEAR_DEFAULT) {
				STm->default_density = (-1);
				printk(KERN_INFO "st%d: Density default disabled.\n",
                                       dev);
			} else {
				STm->default_density = value & 0xff;
				printk(KERN_INFO "st%d: Density default set to %x\n",
				       dev, STm->default_density);
				if (STp->ready == ST_READY) {
					STp->density_changed = FALSE;
					set_mode_densblk(STp, STm);
				}
			}
		} else if (code == MT_ST_DEF_DRVBUFFER) {
			if (value == MT_ST_CLEAR_DEFAULT) {
				STp->default_drvbuffer = 0xff;
				printk(KERN_INFO
                                       "st%d: Drive buffer default disabled.\n", dev);
			} else {
				STp->default_drvbuffer = value & 7;
				printk(KERN_INFO
                                       "st%d: Drive buffer default set to %x\n",
				       dev, STp->default_drvbuffer);
				if (STp->ready == ST_READY)
					st_int_ioctl(STp, MTSETDRVBUFFER, STp->default_drvbuffer);
			}
		} else if (code == MT_ST_DEF_COMPRESSION) {
			if (value == MT_ST_CLEAR_DEFAULT) {
				STm->default_compression = ST_DONT_TOUCH;
				printk(KERN_INFO
                                       "st%d: Compression default disabled.\n", dev);
			} else {
				if ((value & 0xff00) != 0) {
					STp->c_algo = (value & 0xff00) >> 8;
					printk(KERN_INFO "st%d: Compression algorithm set to 0x%x.\n",
					       dev, STp->c_algo);
				}
				if ((value & 0xff) != 0xff) {
					STm->default_compression = (value & 1 ? ST_YES : ST_NO);
					printk(KERN_INFO "st%d: Compression default set to %x\n",
					       dev, (value & 1));
					if (STp->ready == ST_READY) {
						STp->compression_changed = FALSE;
						st_compression(STp, (STm->default_compression == ST_YES));
					}
				}
			}
		}
	} else
		return (-EIO);

	return 0;
}

#define MODE_HEADER_LENGTH  4

/* Mode header and page byte offsets */
#define MH_OFF_DATA_LENGTH     0
#define MH_OFF_MEDIUM_TYPE     1
#define MH_OFF_DEV_SPECIFIC    2
#define MH_OFF_BDESCS_LENGTH   3
#define MP_OFF_PAGE_NBR        0
#define MP_OFF_PAGE_LENGTH     1

/* Mode header and page bit masks */
#define MH_BIT_WP              0x80
#define MP_MSK_PAGE_NBR        0x3f

/* Don't return block descriptors */
#define MODE_SENSE_OMIT_BDESCS 0x08

#define MODE_SELECT_PAGE_FORMAT 0x10

/* Read a mode page into the tape buffer. The block descriptors are included
   if incl_block_descs is true. The page control is ored to the page number
   parameter, if necessary. */
static int read_mode_page(Scsi_Tape *STp, int page, int omit_block_descs)
{
	unsigned char cmd[MAX_COMMAND_SIZE];
	Scsi_Request *SRpnt = NULL;

	memset(cmd, 0, MAX_COMMAND_SIZE);
	cmd[0] = MODE_SENSE;
	if (omit_block_descs)
		cmd[1] = MODE_SENSE_OMIT_BDESCS;
	cmd[2] = page;
	cmd[4] = 255;

	SRpnt = st_do_scsi(SRpnt, STp, cmd, cmd[4], SCSI_DATA_READ,
			   STp->timeout, 0, TRUE);
	if (SRpnt == NULL)
		return (STp->buffer)->syscall_result;

	scsi_release_request(SRpnt);

	return (STp->buffer)->syscall_result;
}


/* Send the mode page in the tape buffer to the drive. Assumes that the mode data
   in the buffer is correctly formatted. */
static int write_mode_page(Scsi_Tape *STp, int page)
{
	int pgo;
	unsigned char cmd[MAX_COMMAND_SIZE];
	Scsi_Request *SRpnt = NULL;

	memset(cmd, 0, MAX_COMMAND_SIZE);
	cmd[0] = MODE_SELECT;
	cmd[1] = MODE_SELECT_PAGE_FORMAT;
	pgo = MODE_HEADER_LENGTH + (STp->buffer)->b_data[MH_OFF_BDESCS_LENGTH];
	cmd[4] = pgo + (STp->buffer)->b_data[pgo + MP_OFF_PAGE_LENGTH] + 2;

	/* Clear reserved fields */
	(STp->buffer)->b_data[MH_OFF_DATA_LENGTH] = 0;
	(STp->buffer)->b_data[MH_OFF_MEDIUM_TYPE] = 0;
	(STp->buffer)->b_data[MH_OFF_DEV_SPECIFIC] &= ~MH_BIT_WP;
	(STp->buffer)->b_data[pgo + MP_OFF_PAGE_NBR] &= MP_MSK_PAGE_NBR;

	SRpnt = st_do_scsi(SRpnt, STp, cmd, cmd[4], SCSI_DATA_WRITE,
			   STp->timeout, 0, TRUE);
	if (SRpnt == NULL)
		return (STp->buffer)->syscall_result;

	scsi_release_request(SRpnt);

	return (STp->buffer)->syscall_result;
}


#define COMPRESSION_PAGE        0x0f
#define COMPRESSION_PAGE_LENGTH 16

#define CP_OFF_DCE_DCC          2
#define CP_OFF_C_ALGO           7

#define DCE_MASK  0x80
#define DCC_MASK  0x40
#define RED_MASK  0x60


/* Control the compression with mode page 15. Algorithm not changed if zero.

   The block descriptors are read and written because Sony SDT-7000 does not
   work without this (suggestion from Michael Schaefer <[e-mail]>).
   Including block descriptors should not cause any harm to other drives. */

static int st_compression(Scsi_Tape * STp, int state)
{
	int retval;
	int mpoffs;  /* Offset to mode page start */
	unsigned char *b_data = (STp->buffer)->b_data;
	DEB( int dev = TAPE_NR(STp->devt); )

	if (STp->ready != ST_READY)
		return (-EIO);

	/* Read the current page contents */
	retval = read_mode_page(STp, COMPRESSION_PAGE, FALSE);
	if (retval) {
                DEBC(printk(ST_DEB_MSG "st%d: Compression mode page not supported.\n",
                            dev));
		return (-EIO);
	}

	mpoffs = MODE_HEADER_LENGTH + b_data[MH_OFF_BDESCS_LENGTH];
        DEBC(printk(ST_DEB_MSG "st%d: Compression state is %d.\n", dev,
                    (b_data[mpoffs + CP_OFF_DCE_DCC] & DCE_MASK ? 1 : 0)));

	/* Check if compression can be changed */
	if ((b_data[mpoffs + CP_OFF_DCE_DCC] & DCC_MASK) == 0) {
                DEBC(printk(ST_DEB_MSG "st%d: Compression not supported.\n", dev));
		return (-EIO);
	}

	/* Do the change */
	if (state) {
		b_data[mpoffs + CP_OFF_DCE_DCC] |= DCE_MASK;
		if (STp->c_algo != 0)
			b_data[mpoffs + CP_OFF_C_ALGO] = STp->c_algo;
	}
	else {
		b_data[mpoffs + CP_OFF_DCE_DCC] &= ~DCE_MASK;
		if (STp->c_algo != 0)
			b_data[mpoffs + CP_OFF_C_ALGO] = 0; /* no compression */
	}

	retval = write_mode_page(STp, COMPRESSION_PAGE);
	if (retval) {
                DEBC(printk(ST_DEB_MSG "st%d: Compression change failed.\n", dev));
		return (-EIO);
	}
        DEBC(printk(ST_DEB_MSG "st%d: Compression state changed to %d.\n",
		       dev, state));

	STp->compression_changed = TRUE;
	return 0;
}


/* Process the load and unload commands (does unload if the load code is zero) */
static int do_load_unload(Scsi_Tape *STp, struct file *filp, int load_code)
{
	int retval = (-EIO), timeout;
	DEB(int dev = TAPE_NR(STp->devt);)
	unsigned char cmd[MAX_COMMAND_SIZE];
	ST_partstat *STps;
	Scsi_Request *SRpnt;

	if (STp->ready != ST_READY && !load_code) {
		if (STp->ready == ST_NO_TAPE)
			return (-ENOMEDIUM);
		else
			return (-EIO);
	}

	memset(cmd, 0, MAX_COMMAND_SIZE);
	cmd[0] = START_STOP;
	if (load_code)
		cmd[4] |= 1;
	/*
	 * If arg >= 1 && arg <= 6 Enhanced load/unload in HP C1553A
	 */
	if (load_code >= 1 + MT_ST_HPLOADER_OFFSET
	    && load_code <= 6 + MT_ST_HPLOADER_OFFSET) {
		DEBC(printk(ST_DEB_MSG "st%d: Enhanced %sload slot %2d.\n",
			    dev, (cmd[4]) ? "" : "un",
			    load_code - MT_ST_HPLOADER_OFFSET));
		cmd[3] = load_code - MT_ST_HPLOADER_OFFSET; /* MediaID field of C1553A */
	}
	if (STp->immediate) {
		cmd[1] = 1;	/* Don't wait for completion */
		timeout = STp->timeout;
	}
	else
		timeout = STp->long_timeout;

	DEBC(
		if (!load_code)
		printk(ST_DEB_MSG "st%d: Unloading tape.\n", dev);
		else
		printk(ST_DEB_MSG "st%d: Loading tape.\n", dev);
		);

	SRpnt = st_do_scsi(NULL, STp, cmd, 0, SCSI_DATA_NONE,
			   timeout, MAX_RETRIES, TRUE);
	if (!SRpnt)
		return (STp->buffer)->syscall_result;

	retval = (STp->buffer)->syscall_result;
	scsi_release_request(SRpnt);

	if (!retval) {	/* SCSI command successful */

		if (!load_code)
			STp->rew_at_close = 0;
		else
			STp->rew_at_close = STp->autorew_dev;

		retval = check_tape(STp, filp);
		if (retval > 0)
			retval = 0;
	}
	else {
		STps = &(STp->ps[STp->partition]);
		STps->drv_file = STps->drv_block = (-1);
	}

	return retval;
}


/* Internal ioctl function */
static int st_int_ioctl(Scsi_Tape *STp, unsigned int cmd_in, unsigned long arg)
{
	int timeout;
	long ltmp;
	int ioctl_result;
	int chg_eof = TRUE;
	unsigned char cmd[MAX_COMMAND_SIZE];
	Scsi_Request *SRpnt;
	ST_partstat *STps;
	int fileno, blkno, at_sm, undone;
	int datalen = 0, direction = SCSI_DATA_NONE;
	int dev = TAPE_NR(STp->devt);

	if (STp->ready != ST_READY) {
		if (STp->ready == ST_NO_TAPE)
			return (-ENOMEDIUM)