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Diffstat (limited to 'linux/src/drivers/scsi/scsi.h')
| -rw-r--r-- | linux/src/drivers/scsi/scsi.h | 632 |
1 files changed, 632 insertions, 0 deletions
diff --git a/linux/src/drivers/scsi/scsi.h b/linux/src/drivers/scsi/scsi.h new file mode 100644 index 0000000..c3dfcd4 --- /dev/null +++ b/linux/src/drivers/scsi/scsi.h @@ -0,0 +1,632 @@ +/* + * 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 + +#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 + +/* + * 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: + */ |