ide-floppy.c

基于组件方式开发操作系统的OSKIT源代码

/*
 * linux/drivers/block/ide-floppy.c	Version 0.9		Jul   4, 1999
 *
 * Copyright (C) 1996 - 1999 Gadi Oxman <[e-mail]>
 */

/*
 * IDE ATAPI floppy driver.
 *
 * The driver currently doesn't have any fancy features, just the bare
 * minimum read/write support.
 *
 * Many thanks to Lode Leroy <[e-mail]>, who tested so many
 * ALPHA patches to this driver on an EASYSTOR LS-120 ATAPI floppy drive.
 *
 * Ver 0.1   Oct 17 96   Initial test version, mostly based on ide-tape.c.
 * Ver 0.2   Oct 31 96   Minor changes.
 * Ver 0.3   Dec  2 96   Fixed error recovery bug.
 * Ver 0.4   Jan 26 97   Add support for the HDIO_GETGEO ioctl.
 * Ver 0.5   Feb 21 97   Add partitions support.
 *                       Use the minimum of the LBA and CHS capacities.
 *                       Avoid hwgroup->rq == NULL on the last irq.
 *                       Fix potential null dereferencing with DEBUG_LOG.
 * Ver 0.8   Dec  7 97   Increase irq timeout from 10 to 50 seconds.
 *                       Add media write-protect detection.
 *                       Issue START command only if TEST UNIT READY fails.
 *                       Add work-around for IOMEGA ZIP revision 21.D.
 *                       Remove idefloppy_get_capabilities().
 * Ver 0.9   Jul  4 99   Fix a bug which might have caused the number of
 *                        bytes requested on each interrupt to be zero.
 *                        Thanks to <[e-mail]> for pointing this out.
 */

#define IDEFLOPPY_VERSION "0.9"

#include <linux/config.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/timer.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/major.h>
#include <linux/errno.h>
#include <linux/genhd.h>
#include <linux/malloc.h>
#include <linux/cdrom.h>

#include <asm/byteorder.h>
#include <asm/irq.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include <asm/unaligned.h>
#include <asm/bitops.h>

/*
 *	Main Linux ide driver include file
 */
#include "ide.h"

/*
 *	The following are used to debug the driver.
 */
#define IDEFLOPPY_DEBUG_LOG		0
#define IDEFLOPPY_DEBUG_INFO		0
#define IDEFLOPPY_DEBUG_BUGS		1

/*
 *	Some drives require a longer irq timeout.
 */
#define IDEFLOPPY_WAIT_CMD		(5 * WAIT_CMD)

/*
 *	After each failed packet command we issue a request sense command
 *	and retry the packet command IDEFLOPPY_MAX_PC_RETRIES times.
 */
#define IDEFLOPPY_MAX_PC_RETRIES	3

/*
 *	With each packet command, we allocate a buffer of
 *	IDEFLOPPY_PC_BUFFER_SIZE bytes.
 */
#define IDEFLOPPY_PC_BUFFER_SIZE	256

/*
 *	In various places in the driver, we need to allocate storage
 *	for packet commands and requests, which will remain valid while
 *	we leave the driver to wait for an interrupt or a timeout event.
 */
#define IDEFLOPPY_PC_STACK		(10 + IDEFLOPPY_MAX_PC_RETRIES)

/*
 *	Our view of a packet command.
 */
typedef struct idefloppy_packet_command_s {
	u8 c[12];				/* Actual packet bytes */
	int retries;				/* On each retry, we increment retries */
	int error;				/* Error code */
	int request_transfer;			/* Bytes to transfer */
	int actually_transferred;		/* Bytes actually transferred */
	int buffer_size;			/* Size of our data buffer */
	char *b_data;				/* Pointer which runs on the buffers */
	int b_count;				/* Missing/Available data on the current buffer */
	struct request *rq;			/* The corresponding request */
	byte *buffer;				/* Data buffer */
	byte *current_position;			/* Pointer into the above buffer */
	void (*callback) (ide_drive_t *);	/* Called when this packet command is completed */
	byte pc_buffer[IDEFLOPPY_PC_BUFFER_SIZE];	/* Temporary buffer */
	unsigned int flags;			/* Status/Action bit flags */
} idefloppy_pc_t;

/*
 *	Packet command flag bits.
 */
#define	PC_ABORT			0	/* Set when an error is considered normal - We won't retry */
#define PC_DMA_RECOMMENDED		2	/* 1 when we prefer to use DMA if possible */
#define	PC_DMA_IN_PROGRESS		3	/* 1 while DMA in progress */
#define	PC_DMA_ERROR			4	/* 1 when encountered problem during DMA */
#define	PC_WRITING			5	/* Data direction */

/*
 *	Removable Block Access Capabilities Page
 */
typedef struct {
#if defined(__LITTLE_ENDIAN_BITFIELD)
	unsigned	page_code	:6;	/* Page code - Should be 0x1b */
	unsigned	reserved1_6	:1;	/* Reserved */
	unsigned	ps		:1;	/* Should be 0 */
#elif defined(__BIG_ENDIAN_BITFIELD)
	unsigned	ps		:1;	/* Should be 0 */
	unsigned	reserved1_6	:1;	/* Reserved */
	unsigned	page_code	:6;	/* Page code - Should be 0x1b */
#else
#error "Bitfield endianness not defined! Check your byteorder.h"
#endif
	u8		page_length;		/* Page Length - Should be 0xa */
#if defined(__LITTLE_ENDIAN_BITFIELD)
	unsigned	reserved2	:6;
	unsigned	srfp		:1;	/* Supports reporting progress of format */
	unsigned	sflp		:1;	/* System floppy type device */
	unsigned	tlun		:3;	/* Total logical units supported by the device */
	unsigned	reserved3	:3;
	unsigned	sml		:1;	/* Single / Multiple lun supported */
	unsigned	ncd		:1;	/* Non cd optical device */
#elif defined(__BIG_ENDIAN_BITFIELD)
	unsigned	sflp		:1;	/* System floppy type device */
	unsigned	srfp		:1;	/* Supports reporting progress of format */
	unsigned	reserved2	:6;
	unsigned	ncd		:1;	/* Non cd optical device */
	unsigned	sml		:1;	/* Single / Multiple lun supported */
	unsigned	reserved3	:3;
	unsigned	tlun		:3;	/* Total logical units supported by the device */
#else
#error "Bitfield endianness not defined! Check your byteorder.h"
#endif
	u8		reserved[8];
} idefloppy_capabilities_page_t;

/*
 *	Flexible disk page.
 */
typedef struct {
#if defined(__LITTLE_ENDIAN_BITFIELD)
	unsigned	page_code	:6;	/* Page code - Should be 0x5 */
	unsigned	reserved1_6	:1;	/* Reserved */
	unsigned	ps		:1;	/* The device is capable of saving the page */
#elif defined(__BIG_ENDIAN_BITFIELD)
	unsigned	ps		:1;	/* The device is capable of saving the page */
	unsigned	reserved1_6	:1;	/* Reserved */
	unsigned	page_code	:6;	/* Page code - Should be 0x5 */
#else
#error "Bitfield endianness not defined! Check your byteorder.h"
#endif
	u8		page_length;		/* Page Length - Should be 0x1e */
	u16		transfer_rate;		/* In kilobits per second */
	u8		heads, sectors;		/* Number of heads, Number of sectors per track */
	u16		sector_size;		/* Byes per sector */
	u16		cyls;			/* Number of cylinders */
	u8		reserved10[10];
	u8		motor_delay;		/* Motor off delay */
	u8		reserved21[7];
	u16		rpm;			/* Rotations per minute */
	u8		reserved30[2];
} idefloppy_flexible_disk_page_t;
 
/*
 *	Format capacity
 */
typedef struct {
	u8		reserved[3];
	u8		length;			/* Length of the following descriptors in bytes */
} idefloppy_capacity_header_t;

typedef struct {
	u32		blocks;			/* Number of blocks */
#if defined(__LITTLE_ENDIAN_BITFIELD)
	unsigned	dc		:2;	/* Descriptor Code */
	unsigned	reserved	:6;
#elif defined(__BIG_ENDIAN_BITFIELD)
	unsigned	reserved	:6;
	unsigned	dc		:2;	/* Descriptor Code */
#else
#error "Bitfield endianness not defined! Check your byteorder.h"
#endif
	u8		length_msb;		/* Block Length (MSB)*/
	u16		length;			/* Block Length */
} idefloppy_capacity_descriptor_t;

#define CAPACITY_INVALID	0x00
#define CAPACITY_UNFORMATTED	0x01
#define CAPACITY_CURRENT	0x02
#define CAPACITY_NO_CARTRIDGE	0x03

/*
 *	Most of our global data which we need to save even as we leave the
 *	driver due to an interrupt or a timer event is stored in a variable
 *	of type idefloppy_floppy_t, defined below.
 */
typedef struct {
	ide_drive_t *drive;

	idefloppy_pc_t *pc;			/* Current packet command */
	idefloppy_pc_t *failed_pc; 		/* Last failed packet command */
	idefloppy_pc_t pc_stack[IDEFLOPPY_PC_STACK];/* Packet command stack */
	int pc_stack_index;			/* Next free packet command storage space */
	struct request rq_stack[IDEFLOPPY_PC_STACK];
	int rq_stack_index;			/* We implement a circular array */

	/*
	 *	Last error information
	 */
	byte sense_key, asc, ascq;

	/*
	 *	Device information
	 */
	int blocks, block_size, bs_factor;			/* Current format */
	idefloppy_capacity_descriptor_t capacity;		/* Last format capacity */
	idefloppy_flexible_disk_page_t flexible_disk_page;	/* Copy of the flexible disk page */
	int wp;							/* Write protect */

	unsigned int flags;			/* Status/Action flags */
} idefloppy_floppy_t;

/*
 *	Floppy flag bits values.
 */
#define IDEFLOPPY_DRQ_INTERRUPT		0	/* DRQ interrupt device */
#define IDEFLOPPY_MEDIA_CHANGED		1	/* Media may have changed */
#define IDEFLOPPY_USE_READ12		2	/* Use READ12/WRITE12 or READ10/WRITE10 */

/*
 *	ATAPI floppy drive packet commands
 */
#define IDEFLOPPY_FORMAT_UNIT_CMD	0x04
#define IDEFLOPPY_INQUIRY_CMD		0x12
#define IDEFLOPPY_MODE_SELECT_CMD	0x55
#define IDEFLOPPY_MODE_SENSE_CMD	0x5a
#define IDEFLOPPY_READ10_CMD		0x28
#define IDEFLOPPY_READ12_CMD		0xa8
#define IDEFLOPPY_READ_CAPACITY_CMD	0x23
#define IDEFLOPPY_REQUEST_SENSE_CMD	0x03
#define IDEFLOPPY_PREVENT_REMOVAL_CMD	0x1e
#define IDEFLOPPY_SEEK_CMD		0x2b
#define IDEFLOPPY_START_STOP_CMD	0x1b
#define IDEFLOPPY_TEST_UNIT_READY_CMD	0x00
#define IDEFLOPPY_VERIFY_CMD		0x2f
#define IDEFLOPPY_WRITE10_CMD		0x2a
#define IDEFLOPPY_WRITE12_CMD		0xaa
#define IDEFLOPPY_WRITE_VERIFY_CMD	0x2e

/*
 *	Defines for the mode sense command
 */
#define MODE_SENSE_CURRENT		0x00
#define MODE_SENSE_CHANGEABLE		0x01
#define MODE_SENSE_DEFAULT		0x02 
#define MODE_SENSE_SAVED		0x03

/*
 *	Special requests for our block device strategy routine.
 */
#define	IDEFLOPPY_FIRST_RQ		90

/*
 * 	IDEFLOPPY_PC_RQ is used to queue a packet command in the request queue.
 */
#define	IDEFLOPPY_PC_RQ			90

#define IDEFLOPPY_LAST_RQ		90

/*
 *	A macro which can be used to check if a given request command
 *	originated in the driver or in the buffer cache layer.
 */
#define IDEFLOPPY_RQ_CMD(cmd) 		((cmd >= IDEFLOPPY_FIRST_RQ) && (cmd <= IDEFLOPPY_LAST_RQ))

/*
 *	Error codes which are returned in rq->errors to the higher part
 *	of the driver.
 */
#define	IDEFLOPPY_ERROR_GENERAL		101

/*
 *	The ATAPI Status Register.
 */
typedef union {
	unsigned all			:8;
	struct {
#if defined(__LITTLE_ENDIAN_BITFIELD)
		unsigned check		:1;	/* Error occurred */
		unsigned idx		:1;	/* Reserved */
		unsigned corr		:1;	/* Correctable error occurred */
		unsigned drq		:1;	/* Data is request by the device */
		unsigned dsc		:1;	/* Media access command finished */
		unsigned reserved5	:1;	/* Reserved */
		unsigned drdy		:1;	/* Ignored for ATAPI commands (ready to accept ATA command) */
		unsigned bsy		:1;	/* The device has access to the command block */
#elif defined(__BIG_ENDIAN_BITFIELD)
		unsigned bsy		:1;	/* The device has access to the command block */
		unsigned drdy		:1;	/* Ignored for ATAPI commands (ready to accept ATA command) */
		unsigned reserved5	:1;	/* Reserved */
		unsigned dsc		:1;	/* Media access command finished */
		unsigned drq		:1;	/* Data is request by the device */
		unsigned corr		:1;	/* Correctable error occurred */
		unsigned idx		:1;	/* Reserved */
		unsigned check		:1;	/* Error occurred */
#else
#error "Bitfield endianness not defined! Check your byteorder.h"
#endif
	} b;
} idefloppy_status_reg_t;

/*
 *	The ATAPI error register.
 */
typedef union {
	unsigned all			:8;
	struct {
#if defined(__LITTLE_ENDIAN_BITFIELD)
		unsigned ili		:1;	/* Illegal Length Indication */
		unsigned eom		:1;	/* End Of Media Detected */
		unsigned abrt		:1;	/* Aborted command - As defined by ATA */
		unsigned mcr		:1;	/* Media Change Requested - As defined by ATA */
		unsigned sense_key	:4;	/* Sense key of the last failed packet command */
#elif defined(__BIG_ENDIAN_BITFIELD)
		unsigned sense_key	:4;	/* Sense key of the last failed packet command */
		unsigned mcr		:1;	/* Media Change Requested - As defined by ATA */
		unsigned abrt		:1;	/* Aborted command - As defined by ATA */
		unsigned eom		:1;	/* End Of Media Detected */
		unsigned ili		:1;	/* Illegal Length Indication */
#else
#error "Bitfield endianness not defined! Check your byteorder.h"
#endif
	} b;
} idefloppy_error_reg_t;

/*
 *	ATAPI Feature Register
 */
typedef union {
	unsigned all			:8;
	struct {
#if defined(__LITTLE_ENDIAN_BITFIELD)
		unsigned dma		:1;	/* Using DMA or PIO */
		unsigned reserved321	:3;	/* Reserved */
		unsigned reserved654	:3;	/* Reserved (Tag Type) */
		unsigned reserved7	:1;	/* Reserved */
#elif defined(__BIG_ENDIAN_BITFIELD)
		unsigned reserved7	:1;	/* Reserved */
		unsigned reserved654	:3;	/* Reserved (Tag Type) */
		unsigned reserved321	:3;	/* Reserved */
		unsigned dma		:1;	/* Using DMA or PIO */
#else
#error "Bitfield endianness not defined! Check your byteorder.h"
#endif
	} b;
} idefloppy_feature_reg_t;

/*
 *	ATAPI Byte Count Register.
 */
typedef union {
	unsigned all			:16;
	struct {
#if defined(__LITTLE_ENDIAN_BITFIELD)
		unsigned low		:8;	/* LSB */
		unsigned high		:8;	/* MSB */
#elif defined(__BIG_ENDIAN_BITFIELD)
		unsigned high		:8;	/* MSB */
		unsigned low		:8;	/* LSB */
#else
#error "Bitfield endianness not defined! Check your byteorder.h"
#endif
	} b;
} idefloppy_bcount_reg_t;

/*
 *	ATAPI Interrupt Reason Register.
 */
typedef union {
	unsigned all			:8;
	struct {
#if defined(__LITTLE_ENDIAN_BITFIELD)
		unsigned cod		:1;	/* Information transferred is command (1) or data (0) */
		unsigned io		:1;	/* The device requests us to read (1) or write (0) */
		unsigned reserved	:6;	/* Reserved */
#elif defined(__BIG_ENDIAN_BITFIELD)
		unsigned reserved	:6;	/* Reserved */
		unsigned io		:1;	/* The device requests us to read (1) or write (0) */
		unsigned cod		:1;	/* Information transferred is command (1) or data (0) */
#else
#error "Bitfield endianness not defined! Check your byteorder.h"