dtread.c

Linux磁盘测试的源代码,测试磁盘的读写性能

/****************************************************************************
 *									    *
 *			  COPYRIGHT (c) 1990 - 2004			    *
 *			   This Software Provided			    *
 *				     By					    *
 *			  Robin's Nest Software Inc.			    *
 *									    *
 * Permission to use, copy, modify, distribute and sell this software and   *
 * its documentation for any purpose and without fee is hereby granted,	    *
 * provided that the above copyright notice appear in all copies and that   *
 * both that copyright notice and this permission notice appear in the	    *
 * supporting documentation, and that the name of the author not be used    *
 * in advertising or publicity pertaining to distribution of the software   *
 * without specific, written prior permission.				    *
 *									    *
 * THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, 	    *
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN	    *
 * NO EVENT SHALL HE BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL   *
 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR    *
 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS  *
 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF   *
 * THIS SOFTWARE.							    *
 *									    *
 ****************************************************************************/
/*
 * Module:	dtread.c
 * Author:	Robin T. Miller
 *
 * Description:
 *	Read routines for generic data test program.
 */
#include "dt.h"
#if !defined(_QNX_SOURCE)
#  include <sys/file.h>
#endif /* !defined(_QNX_SOURCE) */
#include <sys/stat.h>

/*
 * Modification History:
 *
 * February 13th, 2004 by Robin Miller.
 *      Factor in the file position when doing reverse I/O, to avoid
 * reading into that area (which is now deemed protected).
 *
 * November 17th, 2003 by Robin Miller.
 *	Breakup output to stdout or stderr, rather than writing
 * all output to stderr.  If output file is stdout ('-') or a log
 * file is specified, then all output reverts to stderr.
 *
 * October 8th, 2003 by Robin Miller.
 *	On AIX, accept ENXIO for I/O's pass EOF.
 *
 * March 4th, 2003 by Robin Miller.
 *      Add EOF support for older SunOS release.  This means reads
 * past EOF return EIO, but continue on this to find real capacity.
 *
 * November 20th, 2002 by Robin Miller.
 *	Updated FindCapacity() to expect ENXIO for reads past EOM.
 *
 * June 25th, 2001 by Robin Miller.
 *	Restructured code associated with Tru64 Unix EEI, so we obtain
 * the EEI status for all tape errors, not just EIO errors.
 *
 * January 28th, 2001 by Robin Miller.
 *	Allow FindCapacity() to be called prior to the file being opened
 * The device capacity is necessary early on for the new slices option.
 *
 * January 26th, 2001 by Robin Miller.
 *	Added support for reverse reading.
 *
 * January 24th, 2001 by Robin Miller.
 *	Add support for variable I/O requests sizes.
 *
 * January 14th, 2001 by Robin Miller.
 *	Added support for multiple volumes option.
 *
 * January 2nd, 2001 by Robin Miller.
 *	Remove check for block or character device in FindCapacity(), since
 * that check is already done in mainline code, so it's a duplicate check.
 *
 * December 30th, 2000 by Robin Miller.
 *	Make changes to build using MKS/NuTCracker product.
 *
 * October 2nd, 2000 by Robin Miller.
 *	Update FindCapacity() to accept ENXIO for reads at EOM on
 * SCO UnixWare systems.
 *
 * April 2nd, 2000 by Robin Miller.
 *	Updated FindCapacity(): printf -> Fprintf so messages go to
 * log file, and add/change casts on large_t values (nothing big :-).
 *
 * March 28th, 2000 by Robin Miller.
 *	Modified calls to file position functions which now accept a
 * device information parameter.
 *
 * March 27th, 2000 by Robin Miller.
 *	Modified FindCapacity() to continue on read() errors, to handle
 * broken Linux ATAPI (IDE) driver, which returns EIO on errors past the
 * end of media (damn!).
 *
 * February 18th, 2000 by Robin Miller.
 *	Fix a problem where the records read value was not updated
 * when the data limit was reached first.
 *
 * February 17th, 2000 by Robin Miller.
 *	Adding better support for multi-volume tape testing.  Mainly,
 * make it work with writing multiple tape files, rather than one file.
 *
 * January 17th, 2000 by Robin Miller.
 *	Added checks @ EOF with/multi-volume enabled, so Copy/Verify
 * operations properly prompt for the next volume.  This allows 'dt'
 * to be used as a general purpose multi-volume tool w/other utilities.
 *
 * January 6th, 2000 by Robin Miller.
 *	Added support for multi-volume media.
 *
 * December 30th, 1999 by Robin Miller.
 *	Modify call to do_random() to pass the transfer size.
 *	Fix lbdata problem when using step option (wrong lba).
 *
 * August 6th, 1999 by Robin Miller.
 *      Better parameterizing of "long long" printf formatting.
 *
 * July 22nd, 1999 by Robin Miller.
 *	Added support for IOT (DJ's) test pattern.
 * 
 * May 27, 1999 by Robin Miller.
 *	Adding support for micro-second delays.
 *
 * March 1, 1999 by Robin Miller.
 *	For tapes when Debug is enabled, report the file number.
 *
 * December 21, 1998 by Robin Miller.
 *	Add hooks to handle tape device resets (DUNIX specific).
 *
 * October 29, 1998 by Robin Miller.
 *	Implement a random I/O data limit, instead of using the normal
 * data limit variable (not good to dual purpose this value).
 *
 * October 26, 1998 by Robin Miller.
 *	When random I/O and lbdata options are both enabled, use the
 * file offset seeked to as the starting lbdata address.
 *
 * April 28, 1998 by Robin Miller.
 *	For WIN32/NT, or in O_BINARY into open flags to force binary
 *	mode (the default is text mode).
 *
 * February 29, 1996 by Robin Miller.
 *	Added FindCapacity() function to obtain capacity for random
 *	access devices.  Must set limits for random I/O.
 *
 * February 28, 1996 by Robin Miller.
 *	Added support for copying and verifying device/files.
 *	Modified logic so read errors honor users' error limit.
 *
 * February 23, 1996 by Robin Miller.
 *	Only report partial record warning for sequential I/O testing.
 *	Random I/O can position us towards the end of media often, and
 *	partial transfers are likely especially with large block sizes.
 *
 * November 11, 1995 by Robin Miller.
 *	Fix bug with init'ing and performing pad byte verification.
 *	This caused variable length reads with small increment values
 *	to report an (invalid) pad byte data compare error. e.g.:
 *
 *	% dt of=/dev/rmt0h min=10k max=64k incr=1 pattern=incr
 *
 * July 15, 1995 by Robin Miller.
 *	Fix end of media error handling (ENOSPC), and cleanup code.
 *
 * January 20, 1994 by Robin Miller.
 *	When initializing the data buffer, don't do the entire buffer since
 * init'ing large buffer (e.g. 100m) using min, max, and incr options cause
 * excessive paging and VERY poor performance.
 *
 * September 17, 1993 by Robin Miller.
 *	Report record number on warning errors (for debug).
 *
 * September 4, 1993 by Robin Miller.
 *	Moved memory mapped I/O logic to seperate module.
 *
 * Septemeber 1, 1993 by Robin Miller.
 *	Add ability to read variable record sizes.
 *
 * August 31, 1993 by Robin Miller.
 *	Rotate starting data buffer address through sizeof(long).
 *
 * August 27, 1993 by Robin MIller.
 *	Added support for DEC OSF/1 POSIX Asynchronous I/O (AIO).
 *
 * August 18, 1992 by Robin Miller.
 *	If "step=" option was specified, then seek that many bytes
 *	before the next read request (for disks).
 *
 * August 10, 1993 by Robin Miller.
 *	Added initializing and checking of buffer pad bytes to ensure
 *	data corruption does *not* occur at the end of read buffers.
 *
 * August 5, 1993 by Robin Miller.
 *	Added support for reading multiple tape files.
 *
 * September 11, 1992 by Robin Miller.
 *	Ensure data limit specified by user is not exceeded, incase
 *	the block size isn't modulo the data limit.
 *
 * September 5, 1992 by Robin Miller.
 *	Initial port to QNX 4.1 Operating System.
 *
 * August 21, 1990 by Robin Miller.
 *	Changed exit status so scripts can detect and handle errors
 *	based on the exit code.  If not success, fatal error, or end
 *	of file/tape, the exit code is the error number (errno).
 *
 * August 7, 1990 by Robin Miller.
 *	If "seek=n" option is specified, then seek that many records
 *	before starting to read.  The "skip=n" option skips records
 *	by reading, while "seek=n" seeks past records.
 */

/************************************************************************
 *									*
 * read_data() - Read and optionally verify data read.			*
 *									*
 * Inputs:	dip = The device information pointer.			*
 *									*
 * Outputs:	Returns SUCCESS/FAILURE = Ok/Error.			*
 *									*
 ************************************************************************/
int
read_data (struct dinfo *dip)
{
    register ssize_t count;
    register size_t bsize, dsize;
    int status = SUCCESS;
    struct dtfuncs *dtf = dip->di_funcs;
    u_int32 lba;

    /*
     * For variable length records, initialize to minimum record size.
     */
    if (min_size) {
	dsize = min_size;
    } else {
	dsize = block_size;
    }
    if (dip->di_random_access) {
	if (io_dir == REVERSE) {
	    (void)set_position(dip, (off_t)rdata_limit);
	}
	lba = get_lba(dip);
	dip->di_offset = get_position(dip);
    } else {
	lba = make_lbdata (dip, dip->di_offset);
    }

    /*
     * Now read and optionally verify the input records.
     */
    while ( (error_count < error_limit) &&
	    (dip->di_fbytes_read < data_limit) &&
	    (dip->di_records_read < record_limit) ) {

	if (volumes_flag && (multi_volume >= volume_limit) &&
		  (dip->di_volume_records >= volume_records)) {
	    break;
	}

	if (rdelay_count) {			/* Optional read delay.	*/
	    mySleep (rdelay_count);
	}

	/*
	 * If data limit was specified, ensure we don't exceed it.
	 */
	if ( (dip->di_fbytes_read + dsize) > data_limit) {
	    bsize = (size_t)(data_limit - dip->di_fbytes_read);
	} else {
	    bsize = dsize;
	}

	if (io_dir == REVERSE) {
	    bsize = MIN((dip->di_offset-file_position), bsize);
	    dip->di_offset = set_position(dip, (off_t)(dip->di_offset - bsize));
	} else if (io_type == RANDOM_IO) {
	    dip->di_offset = do_random (dip, TRUE, bsize);
	}

        if (debug_flag && (bsize != dsize) && !variable_flag) {
            Printf ("Record #%lu, Reading a partial record of %lu bytes...\n",
                                    (dip->di_records_read + 1), bsize);
        }

	if (iot_pattern || lbdata_flag) {
	    lba = make_lbdata (dip, (off_t)(dip->di_volume_bytes + dip->di_offset));
	}

	/*
	 * If requested, rotate the data buffer through ROTATE_SIZE bytes
	 * to force various unaligned buffer accesses.
	 */
	if (rotate_flag) {
	    data_buffer = (base_buffer + (rotate_offset++ % ROTATE_SIZE));
	}

	/*
	 * If we'll be doing a data compare after the read, then
	 * fill the data buffer with the inverted pattern to ensure
	 * the buffer actually gets written into (driver debug mostly).
	 */
	if ((io_mode == TEST_MODE) && compare_flag) {
	    init_buffer (data_buffer, bsize, ~pattern);
	    init_padbytes (data_buffer, bsize, ~pattern);
	    if (iot_pattern) {
		lba = init_iotdata (bsize, lba, lbdata_size);
	    }
	}

	if (Debug_flag) {
	    u_int32 iolba = NO_LBA;
	    if (dip->di_random_access) {
		iolba = (get_position(dip) / dip->di_dsize);
	    } else if (lbdata_flag || iot_pattern) {
		iolba = make_lbdata (dip, (off_t)(dip->di_volume_bytes + dip->di_offset));
	    }
	    report_record(dip, (dip->di_files_read + 1), (dip->di_records_read + 1),
				iolba, READ_MODE, data_buffer, bsize);
	}

	count = read_record (dip, data_buffer, bsize, dsize, &status);
	if (end_of_file) break;		/* Stop reading at end of file. */

	if (status == FAILURE) {
	    if (error_count >= error_limit) break;
	} else if (io_mode == COPY_MODE) {
	    status = copy_record (output_dinfo, data_buffer, count);
	    if ( (error_count >= error_limit) || end_of_file) break;
	} else if (io_mode == VERIFY_MODE) {
	    status = verify_record (output_dinfo, data_buffer, count);
	    if ( (error_count >= error_limit) || end_of_file) break;
	}

	/*
	 * Verify the data (unless disabled).
	 */
	if ( (status != FAILURE) && compare_flag && (io_mode == TEST_MODE) ) {
	    ssize_t vsize = count;
	    status = (*dtf->tf_verify_data)(dip, data_buffer, vsize, pattern, &lba);
	    /*
	     * Verify the pad bytes (if enabled).
	     */
	    if ( (status == SUCCESS) && pad_check) {
		(void) verify_padbytes (dip, data_buffer, vsize, ~pattern, bsize);
	    }
	}

	/*
	 * If we had a partial transfer, perhaps due to an error, adjust
	 * the logical block address in preparation for the next request.
	 */
	if (iot_pattern && ((size_t)count < bsize)) {
	    size_t resid = (bsize - count);
	    lba -= howmany(resid, lbdata_size);
	}

	/*
	 * For variable length records, adjust the next record size.
	 */
	if (min_size) {
	    if (variable_flag) {
		dsize = get_variable (dip);
	    } else {
		dsize += incr_count;
	        if (dsize > max_size) dsize = min_size;
	    }
	}

	dip->di_records_read++;
	dip->di_volume_records++;

	if (io_dir == FORWARD) {
	    dip->di_offset += count;	/* Maintain our own position too! */
	} else if ( (io_type == SEQUENTIAL_IO) &&
		    (dip->di_offset == (off_t) file_position) ) {
	    set_Eof(dip);
	    break;
	}

	if (step_offset) {
	    if (io_dir == FORWARD) {
		dip->di_offset = incr_position (dip, step_offset);
	    } else if ((dip->di_offset -= step_offset) <= (off_t) file_position) {
		set_Eof(dip);
		break;
	    }
	}
    }
    return (status);
}

/************************************************************************
 *									*
 * check_read() - Check status of last read operation.			*
 *									*
 * Inputs:	dip = The device information pointer.			*
 *		count = Number of bytes read.				*
 *		size  = Number of bytes expected.			*
 *									*
 * Outputs:	Returns SUCCESS/FAILURE/WARNING = Ok/Error/Warning	*
 *									*
 ************************************************************************/
int
check_read (struct dinfo *dip, ssize_t count, size_t size)
{
    int status = SUCCESS;