2006-10-08 Thomas Schwinge <tschwinge@gnu.org>

* linux/dev/drivers/scsi/scsi.h: Move file...
	* linux/src/drivers/scsi/scsi.h: ... here.

2 files changed, 19 insertions, 651 deletions

diff --git a/linux/dev/drivers/scsi/scsi.h b/linux/dev/drivers/scsi/scsi.h
deleted file mode 100644
index 13052ba..0000000
--- a/linux/dev/drivers/scsi/scsi.h
+++ /dev/null
@@ -1,650 +0,0 @@
-/*
- *  scsi.h Copyright (C) 1992 Drew Eckhardt 
- *         Copyright (C) 1993, 1994, 1995 Eric Youngdale
- *  generic SCSI package header file by
- *      Initial versions: Drew Eckhardt
- *      Subsequent revisions: Eric Youngdale
- *
- *  <drew@colorado.edu>
- *
- *       Modified by Eric Youngdale eric@aib.com to
- *       add scatter-gather, multiple outstanding request, and other
- *       enhancements.
- */
-
-#ifndef _SCSI_H
-#define _SCSI_H
-
-/*
- * Some of the public constants are being moved to this file.
- * We include it here so that what came from where is transparent.
- */
-#include <scsi/scsi.h>
-
-#include <linux/random.h>
-
-
-/*
- * Some defs, in case these are not defined elsewhere.
- */
-#ifndef TRUE
-# define TRUE 1
-#endif
-#ifndef FALSE
-# define FALSE 0
-#endif
-
-
-extern void scsi_make_blocked_list(void);
-extern volatile int in_scan_scsis;
-extern const unsigned char scsi_command_size[8];
-#define COMMAND_SIZE(opcode) scsi_command_size[((opcode) >> 5) & 7]
-#define IDENTIFY_BASE       0x80
-#define IDENTIFY(can_disconnect, lun)   (IDENTIFY_BASE |\
-		     ((can_disconnect) ?  0x40 : 0) |\
-		     ((lun) & 0x07)) 
-#define MAX_SCSI_DEVICE_CODE 10
-extern const char *const scsi_device_types[MAX_SCSI_DEVICE_CODE];
-
-		 
-    
-/*
- *  the return of the status word will be in the following format :
- *  The low byte is the status returned by the SCSI command, 
- *  with vendor specific bits masked.
- *  
- *  The next byte is the message which followed the SCSI status.
- *  This allows a stos to be used, since the Intel is a little
- *  endian machine.
- *  
- *  The final byte is a host return code, which is one of the following.
- *  
- *  IE 
- *  lsb     msb
- *  status  msg host code   
- *  
- *  Our errors returned by OUR driver, NOT SCSI message.  Or'd with
- *  SCSI message passed back to driver <IF any>.
- */
-
-
-#define DID_OK          0x00 /* NO error                                */
-#define DID_NO_CONNECT  0x01 /* Couldn't connect before timeout period  */
-#define DID_BUS_BUSY    0x02 /* BUS stayed busy through time out period */
-#define DID_TIME_OUT    0x03 /* TIMED OUT for other reason              */
-#define DID_BAD_TARGET  0x04 /* BAD target.                             */
-#define DID_ABORT       0x05 /* Told to abort for some other reason     */
-#define DID_PARITY      0x06 /* Parity error                            */
-#define DID_ERROR       0x07 /* Internal error                          */
-#define DID_RESET       0x08 /* Reset by somebody.                      */
-#define DID_BAD_INTR    0x09 /* Got an interrupt we weren't expecting.  */ 
-#define DRIVER_OK       0x00 /* Driver status                           */ 
-
-/*
- *  These indicate the error that occurred, and what is available.
- */
-
-#define DRIVER_BUSY         0x01
-#define DRIVER_SOFT         0x02
-#define DRIVER_MEDIA        0x03
-#define DRIVER_ERROR        0x04    
-
-#define DRIVER_INVALID      0x05
-#define DRIVER_TIMEOUT      0x06
-#define DRIVER_HARD         0x07
-#define DRIVER_SENSE	    0x08
-
-#define SUGGEST_RETRY       0x10
-#define SUGGEST_ABORT       0x20 
-#define SUGGEST_REMAP       0x30
-#define SUGGEST_DIE         0x40
-#define SUGGEST_SENSE       0x80
-#define SUGGEST_IS_OK       0xff
-
-#define DRIVER_MASK         0x0f
-#define SUGGEST_MASK        0xf0
-
-#define MAX_COMMAND_SIZE    12
-
-/*
- *  SCSI command sets
- */
-
-#define SCSI_UNKNOWN    0
-#define SCSI_1          1
-#define SCSI_1_CCS      2
-#define SCSI_2          3
-
-/*
- *  Every SCSI command starts with a one byte OP-code.
- *  The next byte's high three bits are the LUN of the
- *  device.  Any multi-byte quantities are stored high byte
- *  first, and may have a 5 bit MSB in the same byte
- *  as the LUN.
- */
-
-/*
- *      Manufacturers list
- */
-
-#define SCSI_MAN_UNKNOWN     0
-#define SCSI_MAN_NEC         1
-#define SCSI_MAN_TOSHIBA     2
-#define SCSI_MAN_NEC_OLDCDR  3
-#define SCSI_MAN_SONY        4
-#define SCSI_MAN_PIONEER     5
-
-/*
- *  As the scsi do command functions are intelligent, and may need to
- *  redo a command, we need to keep track of the last command
- *  executed on each one.
- */
-
-#define WAS_RESET       0x01
-#define WAS_TIMEDOUT    0x02
-#define WAS_SENSE       0x04
-#define IS_RESETTING    0x08
-#define IS_ABORTING     0x10
-#define ASKED_FOR_SENSE 0x20
-
-/*
- *  The scsi_device struct contains what we know about each given scsi
- *  device.
- */
-
-typedef struct scsi_device {
-    struct scsi_device * next;      /* Used for linked list */
-
-    unsigned char id, lun, channel;
-
-    unsigned int manufacturer;      /* Manufacturer of device, for using 
-				     * vendor-specific cmd's */
-    int attached;                   /* # of high level drivers attached to 
-				     * this */
-    int access_count;               /* Count of open channels/mounts */
-    struct wait_queue * device_wait;/* Used to wait if device is busy */
-    struct Scsi_Host * host;
-    void (*scsi_request_fn)(void);  /* Used to jumpstart things after an 
-				     * ioctl */
-    struct scsi_cmnd *device_queue; /* queue of SCSI Command structures */
-    void *hostdata;                 /* available to low-level driver */
-    char type;
-    char scsi_level;
-    char vendor[8], model[16], rev[4];
-    unsigned char current_tag;      /* current tag */
-    unsigned char sync_min_period;  /* Not less than this period */
-    unsigned char sync_max_offset;  /* Not greater than this offset */
-    unsigned char queue_depth;	    /* How deep a queue to use */
-
-    unsigned writeable:1;
-    unsigned removable:1; 
-    unsigned random:1;
-    unsigned has_cmdblocks:1;
-    unsigned changed:1;             /* Data invalid due to media change */
-    unsigned busy:1;                /* Used to prevent races */
-    unsigned lockable:1;            /* Able to prevent media removal */
-    unsigned borken:1;              /* Tell the Seagate driver to be 
-				     * painfully slow on this device */ 
-    unsigned tagged_supported:1;    /* Supports SCSI-II tagged queuing */
-    unsigned tagged_queue:1;        /* SCSI-II tagged queuing enabled */
-    unsigned disconnect:1;          /* can disconnect */
-    unsigned soft_reset:1;          /* Uses soft reset option */
-    unsigned sync:1;                /* Negotiate for sync transfers */
-    unsigned single_lun:1;          /* Indicates we should only allow I/O to
-                                     * one of the luns for the device at a 
-                                     * time. */
-    unsigned was_reset:1;           /* There was a bus reset on the bus for 
-                                     * this device */
-    unsigned expecting_cc_ua:1;     /* Expecting a CHECK_CONDITION/UNIT_ATTN
-                                     * because we did a bus reset. */
-} Scsi_Device;
-
-/*
- *  Use these to separate status msg and our bytes
- */
-
-#define status_byte(result) (((result) >> 1) & 0x1f)
-#define msg_byte(result)    (((result) >> 8) & 0xff)
-#define host_byte(result)   (((result) >> 16) & 0xff)
-#define driver_byte(result) (((result) >> 24) & 0xff)
-#define suggestion(result)  (driver_byte(result) & SUGGEST_MASK)
-
-#define sense_class(sense)  (((sense) >> 4) & 0x7)
-#define sense_error(sense)  ((sense) & 0xf)
-#define sense_valid(sense)  ((sense) & 0x80);
-
-/*
- *  These are the SCSI devices available on the system.
- */
-
-extern Scsi_Device * scsi_devices;
-
-extern struct hd_struct * sd;
-
-#if defined(MAJOR_NR) && (MAJOR_NR == SCSI_DISK_MAJOR)
-extern struct hd_struct * sd;
-#endif
-
-/*
- *  Initializes all SCSI devices.  This scans all scsi busses.
- */ 
-
-extern int scsi_dev_init (void);
-
-struct scatterlist {
-    char *  address;    /* Location data is to be transferred to */
-    char * alt_address; /* Location of actual if address is a 
-			 * dma indirect buffer.  NULL otherwise */
-    unsigned int length;
-};
-
-#ifdef __alpha__
-# define ISA_DMA_THRESHOLD (~0UL)
-#else
-# define ISA_DMA_THRESHOLD (0x00ffffff)
-#endif
-#define CONTIGUOUS_BUFFERS(X,Y) ((X->b_data+X->b_size) == Y->b_data)
-
-
-/*
- * These are the return codes for the abort and reset functions.  The mid-level
- * code uses these to decide what to do next.  Each of the low level abort
- * and reset functions must correctly indicate what it has done.
- * The descriptions are written from the point of view of the mid-level code,
- * so that the return code is telling the mid-level drivers exactly what
- * the low level driver has already done, and what remains to be done.
- */
-
-/* We did not do anything.  
- * Wait some more for this command to complete, and if this does not work, 
- * try something more serious. */ 
-#define SCSI_ABORT_SNOOZE 0
-
-/* This means that we were able to abort the command.  We have already
- * called the mid-level done function, and do not expect an interrupt that 
- * will lead to another call to the mid-level done function for this command */
-#define SCSI_ABORT_SUCCESS 1
-
-/* We called for an abort of this command, and we should get an interrupt 
- * when this succeeds.  Thus we should not restore the timer for this
- * command in the mid-level abort function. */
-#define SCSI_ABORT_PENDING 2
-
-/* Unable to abort - command is currently on the bus.  Grin and bear it. */
-#define SCSI_ABORT_BUSY 3
-
-/* The command is not active in the low level code. Command probably
- * finished. */
-#define SCSI_ABORT_NOT_RUNNING 4
-
-/* Something went wrong.  The low level driver will indicate the correct
- * error condition when it calls scsi_done, so the mid-level abort function
- * can simply wait until this comes through */
-#define SCSI_ABORT_ERROR 5
-
-/* We do not know how to reset the bus, or we do not want to.  Bummer.
- * Anyway, just wait a little more for the command in question, and hope that
- * it eventually finishes.  If it never finishes, the SCSI device could
- * hang, so use this with caution. */
-#define SCSI_RESET_SNOOZE 0
-
-/* We do not know how to reset the bus, or we do not want to.  Bummer.
- * We have given up on this ever completing.  The mid-level code will
- * request sense information to decide how to proceed from here. */
-#define SCSI_RESET_PUNT 1
-
-/* This means that we were able to reset the bus.  We have restarted all of
- * the commands that should be restarted, and we should be able to continue
- * on normally from here.  We do not expect any interrupts that will return
- * DID_RESET to any of the other commands in the host_queue, and the mid-level
- * code does not need to do anything special to keep the commands alive. 
- * If a hard reset was performed then all outstanding commands on the
- * bus have been restarted. */
-#define SCSI_RESET_SUCCESS 2
-
-/* We called for a reset of this bus, and we should get an interrupt 
- * when this succeeds.  Each command should get its own status
- * passed up to scsi_done, but this has not happened yet. 
- * If a hard reset was performed, then we expect an interrupt
- * for *each* of the outstanding commands that will have the
- * effect of restarting the commands.
- */
-#define SCSI_RESET_PENDING 3
-
-/* We did a reset, but do not expect an interrupt to signal DID_RESET.
- * This tells the upper level code to request the sense info, and this
- * should keep the command alive. */
-#define SCSI_RESET_WAKEUP 4
-
-/* The command is not active in the low level code. Command probably
-   finished. */
-#define SCSI_RESET_NOT_RUNNING 5
-
-/* Something went wrong, and we do not know how to fix it. */
-#define SCSI_RESET_ERROR 6
-
-#define SCSI_RESET_SYNCHRONOUS		0x01
-#define SCSI_RESET_ASYNCHRONOUS		0x02
-#define SCSI_RESET_SUGGEST_BUS_RESET	0x04
-#define SCSI_RESET_SUGGEST_HOST_RESET	0x08
-/*
- * This is a bitmask that is ored with one of the above codes.
- * It tells the mid-level code that we did a hard reset.
- */
-#define SCSI_RESET_BUS_RESET 0x100
-/*
- * This is a bitmask that is ored with one of the above codes.
- * It tells the mid-level code that we did a host adapter reset.
- */
-#define SCSI_RESET_HOST_RESET 0x200
-/*
- * Used to mask off bits and to obtain the basic action that was
- * performed.  
- */
-#define SCSI_RESET_ACTION   0xff
-
-void *   scsi_malloc(unsigned int);
-int      scsi_free(void *, unsigned int);
-extern unsigned int dma_free_sectors;  /* How much room do we have left */
-extern unsigned int need_isa_buffer;   /* True if some devices need indirection
-					* buffers */
-
-/*
- * The Scsi_Cmnd structure is used by scsi.c internally, and for communication
- * with low level drivers that support multiple outstanding commands.
- */
-typedef struct scsi_pointer {
-    char * ptr;                     /* data pointer */
-    int this_residual;              /* left in this buffer */
-    struct scatterlist *buffer;     /* which buffer */
-    int buffers_residual;           /* how many buffers left */
-    
-    volatile int Status;
-    volatile int Message;
-    volatile int have_data_in;
-    volatile int sent_command;
-    volatile int phase;
-} Scsi_Pointer;
-
-typedef struct scsi_cmnd {
-    struct Scsi_Host * host;
-    Scsi_Device * device;
-    unsigned char target, lun, channel;
-    unsigned char cmd_len;
-    unsigned char old_cmd_len;
-    struct scsi_cmnd *next, *prev, *device_next, *reset_chain;
-    
-    /* These elements define the operation we are about to perform */
-    unsigned char cmnd[12];
-    unsigned request_bufflen;	/* Actual request size */
-    
-    void * request_buffer;	/* Actual requested buffer */
-    
-    /* These elements define the operation we ultimately want to perform */
-    unsigned char data_cmnd[12];
-    unsigned short old_use_sg;	/* We save  use_sg here when requesting
-				 * sense info */
-    unsigned short use_sg;	/* Number of pieces of scatter-gather */
-    unsigned short sglist_len;	/* size of malloc'd scatter-gather list */
-    unsigned short abort_reason;/* If the mid-level code requests an
-				 * abort, this is the reason. */
-    unsigned bufflen;		/* Size of data buffer */
-    void *buffer;		/* Data buffer */
-    
-    unsigned underflow;		/* Return error if less than this amount is 
-				 * transfered */
-    
-    unsigned transfersize;	/* How much we are guaranteed to transfer with
-				 * each SCSI transfer (ie, between disconnect /
-				 * reconnects.	 Probably == sector size */
-    
-    
-    struct request request;	/* A copy of the command we are working on */
-
-    unsigned char sense_buffer[16];  /* Sense for this command, if needed */
-
-    /*
-      A SCSI Command is assigned a nonzero serial_number when internal_cmnd
-      passes it to the driver's queue command function.  The serial_number
-      is cleared when scsi_done is entered indicating that the command has
-      been completed.  If a timeout occurs, the serial number at the moment
-      of timeout is copied into serial_number_at_timeout.  By subsequently
-      comparing the serial_number and serial_number_at_timeout fields
-      during abort or reset processing, we can detect whether the command
-      has already completed.  This also detects cases where the command has
-      completed and the SCSI Command structure has already being reused
-      for another command, so that we can avoid incorrectly aborting or
-      resetting the new command.
-    */
-
-    unsigned long serial_number;
-    unsigned long serial_number_at_timeout;
-
-    int retries;
-    int allowed;
-    int timeout_per_command, timeout_total, timeout;
-
-    /*
-     *	We handle the timeout differently if it happens when a reset, 
-     *	abort, etc are in process. 
-     */
-    unsigned volatile char internal_timeout;
-    
-    unsigned flags;
-    
-    /* These variables are for the cdrom only. Once we have variable size 
-     * buffers in the buffer cache, they will go away. */
-    int this_count; 
-    /* End of special cdrom variables */
-    
-    /* Low-level done function - can be used by low-level driver to point
-     *	to completion function.	 Not used by mid/upper level code. */
-    void (*scsi_done)(struct scsi_cmnd *);  
-    void (*done)(struct scsi_cmnd *);  /* Mid-level done function */
-    
-    /*
-     * The following fields can be written to by the host specific code. 
-     * Everything else should be left alone. 
-     */
-    
-    Scsi_Pointer SCp;	/* Scratchpad used by some host adapters */
-    
-    unsigned char * host_scribble; /* The host adapter is allowed to
-				    * call scsi_malloc and get some memory
-				    * and hang it here.	 The host adapter
-				    * is also expected to call scsi_free
-				    * to release this memory.  (The memory
-				    * obtained by scsi_malloc is guaranteed
-				    * to be at an address < 16Mb). */
-    
-    int result;			   /* Status code from lower level driver */
-    
-    unsigned char tag;		   /* SCSI-II queued command tag */
-    unsigned long pid;		   /* Process ID, starts at 0 */
-} Scsi_Cmnd;	     
-
-/*
- *  scsi_abort aborts the current command that is executing on host host.
- *  The error code, if non zero is returned in the host byte, otherwise 
- *  DID_ABORT is returned in the hostbyte.
- */
-
-extern int scsi_abort (Scsi_Cmnd *, int code);
-
-extern void scsi_do_cmd (Scsi_Cmnd *, const void *cmnd ,
-			 void *buffer, unsigned bufflen, 
-			 void (*done)(struct scsi_cmnd *),
-			 int timeout, int retries);
-
-
-extern Scsi_Cmnd * allocate_device(struct request **, Scsi_Device *, int);
-
-extern Scsi_Cmnd * request_queueable(struct request *, Scsi_Device *);
-extern int scsi_reset (Scsi_Cmnd *, unsigned int);
-
-extern int max_scsi_hosts;
-
-extern void proc_print_scsidevice(Scsi_Device *, char *, int *, int);
-
-extern void print_command(unsigned char *);
-extern void print_sense(const char *, Scsi_Cmnd *);
-extern void print_driverbyte(int scsiresult);
-extern void print_hostbyte(int scsiresult);
-
-extern void scsi_mark_host_reset(struct Scsi_Host *Host);
-extern void scsi_mark_bus_reset(struct Scsi_Host *Host, int channel);
-
-#if defined(MAJOR_NR) && (MAJOR_NR != SCSI_TAPE_MAJOR)
-#include "hosts.h"
-
-static Scsi_Cmnd * end_scsi_request(Scsi_Cmnd * SCpnt, int uptodate, int sectors)
-{
-    struct request * req;
-    struct buffer_head * bh;
-    
-    req = &SCpnt->request;
-    req->errors = 0;
-    if (!uptodate) {
-#if defined(MAJOR_NR) && (MAJOR_NR == SCSI_DISK_MAJOR)
-	printk(DEVICE_NAME " I/O error: dev %s, sector %lu, absolute sector %lu\n",
-	       kdevname(req->rq_dev), req->sector, 
-	       req->sector + sd[MINOR(SCpnt->request.rq_dev)].start_sect);
-#else
-	printk(DEVICE_NAME " I/O error: dev %s, sector %lu\n",
-	       kdevname(req->rq_dev), req->sector);
-#endif
-    }
-    
-    do {
-	if ((bh = req->bh) != NULL) {
-	    req->bh = bh->b_reqnext;
-	    req->nr_sectors -= bh->b_size >> 9;
-	    req->sector += bh->b_size >> 9;
-	    bh->b_reqnext = NULL;
-	    /*
-	     * This is our 'MD IO has finished' event handler.
-	     * note that b_state should be cached in a register
-	     * anyways, so the overhead if this checking is almost 
-	     * zero. But anyways .. we never get OO for free :)
-	     */
-	    if (test_bit(BH_MD, &bh->b_state)) {
-		struct md_personality * pers=(struct md_personality *)bh->personality;
-		pers->end_request(bh,uptodate);
-	    }
-	    /*
-	     * the normal (nonmirrored and no RAID5) case:
-	     */
-	    else {
-		mark_buffer_uptodate(bh, uptodate);
-		unlock_buffer(bh);
-	    }
-	    sectors -= bh->b_size >> 9;
-	    if ((bh = req->bh) != NULL) {
-		req->current_nr_sectors = bh->b_size >> 9;
-		if (req->nr_sectors < req->current_nr_sectors) {
-		    req->nr_sectors = req->current_nr_sectors;
-		    printk("end_scsi_request: buffer-list destroyed\n");
-		}
-	    }
-	}
-    } while(sectors && bh);
-    if (req->bh){
-	req->buffer = bh->b_data;
-	return SCpnt;
-    }
-    DEVICE_OFF(req->rq_dev);
-    if (req->sem != NULL) {
-	up(req->sem);
-    }
-    add_blkdev_randomness(MAJOR(req->rq_dev));
-    
-    if (SCpnt->host->block) {
-	struct Scsi_Host * next;
-	
-	for (next = SCpnt->host->block; next != SCpnt->host;
-	     next = next->block)
-	    wake_up(&next->host_wait);
-    }
-    
-    req->rq_status = RQ_INACTIVE;
-    wake_up(&wait_for_request);
-    wake_up(&SCpnt->device->device_wait);
-    return NULL;
-}
-
-
-/* This is just like INIT_REQUEST, but we need to be aware of the fact
- * that an interrupt may start another request, so we run this with interrupts
- * turned off 
- */
-#define INIT_SCSI_REQUEST       \
-    if (!CURRENT) {             \
-	CLEAR_INTR;             \
-	restore_flags(flags);	\
-	return;                 \
-    }                           \
-    if (MAJOR(CURRENT->rq_dev) != MAJOR_NR)           \
-	panic(DEVICE_NAME ": request list destroyed");\
-    if (CURRENT->bh) {                                \
-	if (!buffer_locked(CURRENT->bh))              \
-	    panic(DEVICE_NAME ": block not locked");  \
-    }
-#endif
-
-#ifdef MACH
-#define SCSI_SLEEP(QUEUE, CONDITION) {		    \
-    if (CONDITION) {			            \
-	struct wait_queue wait = { NULL, NULL};     \
-	add_wait_queue(QUEUE, &wait);		    \
-	for(;;) {			            \
-	if (CONDITION) {		            \
-            if (intr_count)	                    \
-	        panic("scsi: trying to call schedule() in interrupt" \
-		      ", file %s, line %d.\n", __FILE__, __LINE__);  \
-	    schedule();			\
-        }				\
-	else			        \
-	    break;      		\
-	}			        \
-	remove_wait_queue(QUEUE, &wait);\
-    }; }
-#else /* !MACH */
-#define SCSI_SLEEP(QUEUE, CONDITION) {		    \
-    if (CONDITION) {			            \
-	struct wait_queue wait = { current, NULL};  \
-	add_wait_queue(QUEUE, &wait);		    \
-	for(;;) {			            \
-	current->state = TASK_UNINTERRUPTIBLE;	    \
-	if (CONDITION) {		            \
-            if (intr_count)	                    \
-	        panic("scsi: trying to call schedule() in interrupt" \
-		      ", file %s, line %d.\n", __FILE__, __LINE__);  \
-	    schedule();			\
-        }				\
-	else			        \
-	    break;      		\
-	}			        \
-	remove_wait_queue(QUEUE, &wait);\
-	current->state = TASK_RUNNING;	\
-    }; }
-#endif /* !MACH */
-#endif
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-indent-level: 4 
- * c-brace-imaginary-offset: 0
- * c-brace-offset: -4
- * c-argdecl-indent: 4
- * c-label-offset: -4
- * c-continued-statement-offset: 4
- * c-continued-brace-offset: 0
- * indent-tabs-mode: nil
- * tab-width: 8
- * End:
- */
diff --git a/linux/src/drivers/scsi/scsi.h b/linux/src/drivers/scsi/scsi.h
index c3dfcd4..13052ba 100644
--- a/linux/src/drivers/scsi/scsi.h
+++ b/linux/src/drivers/scsi/scsi.h
@@ -591,6 +591,24 @@ static Scsi_Cmnd * end_scsi_request(Scsi_Cmnd * SCpnt, int uptodate, int sectors
     }
 #endif
 
+#ifdef MACH
+#define SCSI_SLEEP(QUEUE, CONDITION) {		    \
+    if (CONDITION) {			            \
+	struct wait_queue wait = { NULL, NULL};     \
+	add_wait_queue(QUEUE, &wait);		    \
+	for(;;) {			            \
+	if (CONDITION) {		            \
+            if (intr_count)	                    \
+	        panic("scsi: trying to call schedule() in interrupt" \
+		      ", file %s, line %d.\n", __FILE__, __LINE__);  \
+	    schedule();			\
+        }				\
+	else			        \
+	    break;      		\
+	}			        \
+	remove_wait_queue(QUEUE, &wait);\
+    }; }
+#else /* !MACH */
 #define SCSI_SLEEP(QUEUE, CONDITION) {		    \
     if (CONDITION) {			            \
 	struct wait_queue wait = { current, NULL};  \
@@ -609,7 +627,7 @@ static Scsi_Cmnd * end_scsi_request(Scsi_Cmnd * SCpnt, int uptodate, int sectors
 	remove_wait_queue(QUEUE, &wait);\
 	current->state = TASK_RUNNING;	\
     }; }
-
+#endif /* !MACH */
 #endif
 
 /*