patch-2.1.15 linux/drivers/scsi/ide-scsi.c

• Lines: 493
• Date: Thu Dec 12 15:48:15 1996
• Orig file: v2.1.14/linux/drivers/scsi/ide-scsi.c
• Orig date: Thu Jan 1 02:00:00 1970

diff -u --recursive --new-file v2.1.14/linux/drivers/scsi/ide-scsi.c linux/drivers/scsi/ide-scsi.c
@@ -0,0 +1,492 @@
+/*
+ * linux/drivers/scsi/ide-scsi.c	Version 0.1 - ALPHA	Dec   3, 1996
+ *
+ * Copyright (C) 1996 Gadi Oxman <gadio@netvision.net.il>
+ */
+
+/*
+ * Emulation of a SCSI host adapter for IDE ATAPI devices.
+ *
+ * With this driver, one can use the Linux SCSI drivers instead of the
+ * native IDE ATAPI drivers.
+ *
+ * Ver 0.1   Dec  3 96   Initial version.
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/ioport.h>
+#include <linux/blkdev.h>
+#include <linux/errno.h>
+#include <linux/hdreg.h>
+#include <linux/malloc.h>
+
+#include <asm/io.h>
+#include <asm/bitops.h>
+
+#include "../block/ide.h"
+
+#include "scsi.h"
+#include "hosts.h"
+#include "sd.h"
+#include "ide-scsi.h"
+
+#define IDESCSI_DEBUG_LOG		0
+
+typedef struct idescsi_pc_s {
+	u8 c[12];				/* Actual packet bytes */
+	int request_transfer;			/* Bytes to transfer */
+	int actually_transferred;		/* Bytes actually transferred */
+	int buffer_size;			/* Size of our data buffer */
+	struct request *rq;			/* The corresponding request */
+	byte *buffer;				/* Data buffer */
+	byte *current_position;			/* Pointer into the above buffer */
+	Scsi_Cmnd *scsi_cmd;			/* SCSI command */
+	void (*done)(Scsi_Cmnd *);		/* Scsi completion routine */
+} idescsi_pc_t;
+
+typedef struct {
+	ide_drive_t *drive;
+	idescsi_pc_t *pc;			/* Current packet command */
+	unsigned int flags;			/* Status/Action flags */
+} idescsi_scsi_t;
+
+#define IDESCSI_DRQ_INTERRUPT		0	/* DRQ interrupt device */
+#define IDESCSI_PC_RQ			90
+
+typedef union {
+	unsigned all			:8;
+	struct {
+		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 */
+	} b;
+} idescsi_status_reg_t;
+
+typedef union {
+	unsigned all			:16;
+	struct {
+		unsigned low		:8;	/* LSB */
+		unsigned high		:8;	/* MSB */
+	} b;
+} idescsi_bcount_reg_t;
+
+typedef union {
+	unsigned all			:8;
+	struct {
+		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 */
+	} b;
+} idescsi_ireason_reg_t;
+
+static void idescsi_discard_data (ide_drive_t *drive, unsigned int bcount)
+{
+	while (bcount--)
+		IN_BYTE (IDE_DATA_REG);
+}
+
+static void idescsi_end_request (byte uptodate, ide_hwgroup_t *hwgroup)
+{
+	ide_drive_t *drive = hwgroup->drive;
+	idescsi_scsi_t *scsi = drive->driver_data;
+	struct request *rq = hwgroup->rq;
+	idescsi_pc_t *pc = (idescsi_pc_t *) rq->buffer;
+
+	if (rq->cmd != IDESCSI_PC_RQ) {
+		ide_end_request (uptodate, hwgroup);
+		return;
+	}
+	ide_end_drive_cmd (drive, 0, 0);
+	if (rq->errors >= ERROR_MAX) {
+#if IDESCSI_DEBUG_LOG
+		printk ("ide-scsi: %s: I/O error for %lu\n", drive->name, pc->scsi_cmd->serial_number);
+#endif /* IDESCSI_DEBUG_LOG */
+		pc->scsi_cmd->result = DID_ERROR << 16;
+	} else if (rq->errors) {
+#if IDESCSI_DEBUG_LOG
+		printk ("ide-scsi: %s: check condition for %lu\n", drive->name, pc->scsi_cmd->serial_number);
+#endif /* IDESCSI_DEBUG_LOG */
+		pc->scsi_cmd->result = (CHECK_CONDITION << 1) | (DID_OK << 16);
+	} else {
+#if IDESCSI_DEBUG_LOG
+		printk ("ide-scsi: %s: success for %lu\n", drive->name, pc->scsi_cmd->serial_number);
+#endif /* IDESCSI_DEBUG_LOG */
+		pc->scsi_cmd->result = DID_OK << 16;
+	}
+	pc->done(pc->scsi_cmd);
+	kfree(pc); kfree(rq);
+	scsi->pc = NULL;
+}
+
+static void idescsi_pc_intr (ide_drive_t *drive)
+{
+	idescsi_scsi_t *scsi = drive->driver_data;
+	idescsi_status_reg_t status;
+	idescsi_bcount_reg_t bcount;
+	idescsi_ireason_reg_t ireason;
+	idescsi_pc_t *pc=scsi->pc;
+	struct request *rq = pc->rq;
+	unsigned int temp;
+
+#if IDESCSI_DEBUG_LOG
+	printk (KERN_INFO "ide-scsi: Reached idescsi_pc_intr interrupt handler\n");
+#endif /* IDESCSI_DEBUG_LOG */	
+
+	status.all = GET_STAT();					/* Clear the interrupt */
+
+	if (!status.b.drq) {						/* No more interrupts */
+#if IDESCSI_DEBUG_LOG
+		printk (KERN_INFO "Packet command completed, %d bytes transferred\n", pc->actually_transferred);
+#endif /* IDESCSI_DEBUG_LOG */
+		ide_sti();
+		if (status.b.check)
+			rq->errors++;
+		idescsi_end_request (1, HWGROUP(drive));
+		return;
+	}
+	bcount.b.high=IN_BYTE (IDE_BCOUNTH_REG);
+       	bcount.b.low=IN_BYTE (IDE_BCOUNTL_REG);
+	ireason.all=IN_BYTE (IDE_IREASON_REG);
+
+	if (ireason.b.cod) {
+		printk (KERN_ERR "ide-scsi: CoD != 0 in idescsi_pc_intr\n");
+		ide_do_reset (drive);
+		return;
+	}
+	if (ireason.b.io) {
+		temp = pc->actually_transferred + bcount.all;
+		if ( temp > pc->request_transfer) {
+			if (temp > pc->buffer_size) {
+				printk (KERN_ERR "ide-scsi: The scsi wants to send us more data than expected - discarding data\n");
+				idescsi_discard_data (drive,bcount.all);
+				ide_set_handler (drive,&idescsi_pc_intr,WAIT_CMD);
+				return;
+			}
+#if IDESCSI_DEBUG_LOG
+			printk (KERN_NOTICE "ide-scsi: The scsi wants to send us more data than expected - allowing transfer\n");
+#endif /* IDESCSI_DEBUG_LOG */
+		}
+	}
+	if (ireason.b.io)
+		atapi_input_bytes (drive,pc->current_position,bcount.all);	/* Read the current buffer */
+	else
+		atapi_output_bytes (drive,pc->current_position,bcount.all);	/* Write the current buffer */
+	pc->actually_transferred+=bcount.all;				/* Update the current position */
+	pc->current_position+=bcount.all;
+
+	ide_set_handler (drive,&idescsi_pc_intr,WAIT_CMD);		/* And set the interrupt handler again */
+}
+
+static void idescsi_transfer_pc (ide_drive_t *drive)
+{
+	idescsi_scsi_t *scsi = drive->driver_data;
+	idescsi_ireason_reg_t ireason;
+
+	if (ide_wait_stat (drive,DRQ_STAT,BUSY_STAT,WAIT_READY)) {
+		printk (KERN_ERR "ide-scsi: Strange, packet command initiated yet DRQ isn't asserted\n");
+		return;
+	}
+	ireason.all=IN_BYTE (IDE_IREASON_REG);
+	if (!ireason.b.cod || ireason.b.io) {
+		printk (KERN_ERR "ide-scsi: (IO,CoD) != (0,1) while issuing a packet command\n");
+		ide_do_reset (drive);
+		return;
+	}
+	ide_set_handler (drive, &idescsi_pc_intr, WAIT_CMD);	/* Set the interrupt routine */
+	atapi_output_bytes (drive, scsi->pc->c, 12);		/* Send the actual packet */
+}
+
+/*
+ *	Issue a packet command
+ */
+static void idescsi_issue_pc (ide_drive_t *drive, idescsi_pc_t *pc)
+{
+	idescsi_scsi_t *scsi = drive->driver_data;
+	idescsi_bcount_reg_t bcount;
+
+	scsi->pc=pc;							/* Set the current packet command */
+	pc->actually_transferred=0;					/* We haven't transferred any data yet */
+	pc->current_position=pc->buffer;
+	bcount.all = IDE_MIN (pc->request_transfer, 63 * 1024);		/* Request to transfer the entire buffer at once */
+
+	OUT_BYTE (drive->ctl,IDE_CONTROL_REG);
+	OUT_BYTE (0,IDE_FEATURE_REG);
+	OUT_BYTE (bcount.b.high,IDE_BCOUNTH_REG);
+	OUT_BYTE (bcount.b.low,IDE_BCOUNTL_REG);
+	OUT_BYTE (drive->select.all,IDE_SELECT_REG);
+
+	if (test_bit (IDESCSI_DRQ_INTERRUPT, &scsi->flags)) {
+		ide_set_handler (drive, &idescsi_transfer_pc, WAIT_CMD);
+		OUT_BYTE (WIN_PACKETCMD, IDE_COMMAND_REG);		/* Issue the packet command */
+	} else {
+		OUT_BYTE (WIN_PACKETCMD, IDE_COMMAND_REG);
+		idescsi_transfer_pc (drive);
+	}
+}
+
+/*
+ *	idescsi_do_request is our request handling function.
+ */
+static void idescsi_do_request (ide_drive_t *drive, struct request *rq, unsigned long block)
+{
+#if IDESCSI_DEBUG_LOG
+	printk (KERN_INFO "rq_status: %d, rq_dev: %u, cmd: %d, errors: %d\n",rq->rq_status,(unsigned int) rq->rq_dev,rq->cmd,rq->errors);
+	printk (KERN_INFO "sector: %ld, nr_sectors: %ld, current_nr_sectors: %ld\n",rq->sector,rq->nr_sectors,rq->current_nr_sectors);
+#endif /* IDESCSI_DEBUG_LOG */
+
+	if (rq->cmd == IDESCSI_PC_RQ) {
+		idescsi_issue_pc (drive, (idescsi_pc_t *) rq->buffer);
+		return;
+	}
+	printk (KERN_ERR "ide-scsi: %s: unsupported command in request queue (%x)\n", drive->name, rq->cmd);
+	idescsi_end_request (0,HWGROUP (drive));
+}
+
+static int idescsi_open (struct inode *inode, struct file *filp, ide_drive_t *drive)
+{
+	MOD_INC_USE_COUNT;
+	return 0;
+}
+
+static void idescsi_ide_release (struct inode *inode, struct file *filp, ide_drive_t *drive)
+{
+	MOD_DEC_USE_COUNT;
+}
+
+static ide_drive_t *idescsi_drives[MAX_HWIFS * MAX_DRIVES];
+static int idescsi_initialized = 0;
+
+/*
+ *	Driver initialization.
+ */
+static void idescsi_setup (ide_drive_t *drive, idescsi_scsi_t *scsi, int id)
+{
+	DRIVER(drive)->busy++;
+	idescsi_drives[id] = drive;
+	drive->driver_data = scsi;
+	drive->ready_stat = 0;
+	memset (scsi, 0, sizeof (idescsi_scsi_t));
+	scsi->drive = drive;
+	if (drive->id && (drive->id->config & 0x0060) == 0x20)
+		set_bit (IDESCSI_DRQ_INTERRUPT, &scsi->flags);
+}
+
+static int idescsi_cleanup (ide_drive_t *drive)
+{
+	idescsi_scsi_t *scsi = drive->driver_data;
+
+	if (ide_unregister_subdriver (drive))
+		return 1;
+	drive->driver_data = NULL;
+	kfree (scsi);
+	return 0;
+}
+
+int idescsi_init (void);
+static ide_module_t idescsi_module = {
+	IDE_DRIVER_MODULE,
+	idescsi_init,
+	NULL
+};
+
+/*
+ *	IDE subdriver functions, registered with ide.c
+ */
+static ide_driver_t idescsi_driver = {
+	ide_scsi,		/* media */
+	0,			/* busy */
+	0,			/* supports_dma */
+	0,			/* supports_dsc_overlap */
+	idescsi_cleanup,	/* cleanup */
+	idescsi_do_request,	/* do_request */
+	idescsi_end_request,	/* end_request */
+	NULL,			/* ioctl */
+	idescsi_open,		/* open */
+	idescsi_ide_release,	/* release */
+	NULL,			/* media_change */
+	NULL,			/* pre_reset */
+	NULL,			/* capacity */
+	NULL			/* special */
+};
+
+static struct proc_dir_entry idescsi_proc_dir = {PROC_SCSI_IDESCSI, 8, "ide-scsi", S_IFDIR | S_IRUGO | S_IXUGO, 2};
+
+/*
+ *	idescsi_init will register the driver for each scsi.
+ */
+int idescsi_init (void)
+{
+	ide_drive_t *drive;
+	idescsi_scsi_t *scsi;
+	byte media[] = {TYPE_DISK, TYPE_TAPE, TYPE_PROCESSOR, TYPE_WORM, TYPE_ROM, TYPE_SCANNER, TYPE_MOD, 255};
+	int i, failed, id;
+
+	if (idescsi_initialized)
+		return 0;
+	idescsi_initialized = 1;
+	for (i = 0; i < MAX_HWIFS * MAX_DRIVES; i++)
+		idescsi_drives[i] = NULL;
+	MOD_INC_USE_COUNT;
+	for (i = 0; media[i] != 255; i++) {
+		failed = 0;
+		while ((drive = ide_scan_devices (media[i], NULL, failed++)) != NULL) {
+			if ((scsi = (idescsi_scsi_t *) kmalloc (sizeof (idescsi_scsi_t), GFP_KERNEL)) == NULL) {
+				printk (KERN_ERR "ide-scsi: %s: Can't allocate a scsi structure\n", drive->name);
+				continue;
+			}
+			if (ide_register_subdriver (drive, &idescsi_driver, IDE_SUBDRIVER_VERSION)) {
+				printk (KERN_ERR "ide-scsi: %s: Failed to register the driver with ide.c\n", drive->name);
+				kfree (scsi);
+				continue;
+			}
+			for (id = 0; id < MAX_HWIFS * MAX_DRIVES && idescsi_drives[id]; id++);
+			idescsi_setup (drive, scsi, id);
+			failed--;
+		}
+	}
+	ide_register_module(&idescsi_module);
+	MOD_DEC_USE_COUNT;
+	return 0;
+}
+
+int idescsi_detect (Scsi_Host_Template *host_template)
+{
+	struct Scsi_Host *host;
+	int id;
+
+	host_template->proc_dir = &idescsi_proc_dir;
+	host = scsi_register(host_template, 0);
+	for (id = 0; id < MAX_HWIFS * MAX_DRIVES && idescsi_drives[id]; id++);
+	host->max_id = id;
+	host->can_queue = host->cmd_per_lun * id;
+	return 1;
+}
+
+int idescsi_release (struct Scsi_Host *host)
+{
+	ide_drive_t *drive;
+	int id;
+
+	for (id = 0; id < MAX_HWIFS * MAX_DRIVES; id++) {
+		drive = idescsi_drives[id];
+		if (drive)
+			DRIVER(drive)->busy--;
+	}
+	return 0;
+}
+
+const char *idescsi_info (struct Scsi_Host *host)
+{
+	return "SCSI host adapter emulation for IDE ATAPI devices";
+}
+
+/*
+ *	Most of the SCSI commands are supported directly by ATAPI devices.
+ *	idescsi_transform_pc handles the few exceptions.
+ */
+static inline void idescsi_transform_pc (ide_drive_t *drive, idescsi_pc_t *pc)
+{
+	if (drive->media == ide_cdrom) {
+		if (pc->c[0] == READ_6) {
+			pc->c[8] = pc->c[4];
+			pc->c[5] = pc->c[3];
+			pc->c[4] = pc->c[2];
+			pc->c[3] = pc->c[1] & 0x1f;
+			pc->c[2] = 0;
+			pc->c[1] &= 0xe0;
+			pc->c[0] = READ_10;
+		}
+	}
+}
+
+int idescsi_queue (Scsi_Cmnd *cmd, void (*done)(Scsi_Cmnd *))
+{
+	ide_drive_t *drive = idescsi_drives[cmd->target];
+	struct request *rq = NULL;
+	idescsi_pc_t *pc = NULL;
+
+#if IDESCSI_DEBUG_LOG
+	printk ("idescsi_queue called, serial = %lu, cmd[0] = %x, id = %d\n", cmd->serial_number, cmd->cmnd[0], cmd->target);
+#endif	/* IDESCSI_DEBUG_LOG */
+
+	if (!drive) {
+		printk (KERN_ERR "ide-scsi: drive id %d not present\n", cmd->target);
+		goto abort;
+	}
+	pc = kmalloc (sizeof (idescsi_pc_t), GFP_ATOMIC);
+	rq = kmalloc (sizeof (struct request), GFP_ATOMIC);
+	if (rq == NULL || pc == NULL) {
+		printk (KERN_ERR "ide-scsi: %s: out of memory\n", drive->name);
+		goto abort;
+	}
+
+	memset (pc->c, 0, 12);
+	pc->rq = rq;
+	memcpy (pc->c, cmd->cmnd, cmd->cmd_len);
+	pc->buffer = cmd->request_buffer;
+	pc->request_transfer = pc->buffer_size = cmd->request_bufflen;
+	pc->scsi_cmd = cmd;
+	pc->done = done;
+	idescsi_transform_pc (drive, pc);
+
+	ide_init_drive_cmd (rq);
+	rq->buffer = (char *) pc;
+	rq->cmd = IDESCSI_PC_RQ;
+	(void) ide_do_drive_cmd (drive, rq, ide_end);
+	return 0;
+abort:
+	if (pc) kfree (pc);
+	if (rq) kfree (rq);
+	cmd->result = DID_ERROR << 16;
+	done(cmd);
+	return 0;
+}
+
+int idescsi_abort (Scsi_Cmnd *cmd)
+{
+	return SCSI_ABORT_SNOOZE;
+}
+
+int idescsi_reset (Scsi_Cmnd *cmd, unsigned int resetflags)
+{
+	return SCSI_RESET_PUNT;
+}
+
+#ifdef MODULE
+Scsi_Host_Template idescsi_template = IDESCSI;
+
+int init_module (void)
+{
+	idescsi_init ();
+	idescsi_template.usage_count = &mod_use_count_;
+	scsi_register_module (MODULE_SCSI_HA, &idescsi_template);
+	return 0;
+}
+
+void cleanup_module (void)
+{
+	ide_drive_t *drive;
+	byte media[] = {TYPE_DISK, TYPE_TAPE, TYPE_PROCESSOR, TYPE_WORM, TYPE_ROM, TYPE_SCANNER, TYPE_MOD, 255};
+	int i, failed;
+
+	scsi_unregister_module (MODULE_SCSI_HA, &idescsi_template);
+	for (i = 0; media[i] != 255; i++) {
+		failed = 0;
+		while ((drive = ide_scan_devices (media[i], &idescsi_driver, failed++)) != NULL)
+			if (idescsi_cleanup (drive)) {
+				printk ("%s: cleanup_module() called while still busy\n", drive->name);
+				failed++;
+			}
+	}
+	ide_unregister_module(&idescsi_module);
+}
+#endif /* MODULE */