root/drivers/scsi/scsi.h

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INCLUDED FROM


DEFINITIONS

This source file includes following definitions.
  1. end_scsi_request

   1 /*
   2  *      scsi.h Copyright (C) 1992 Drew Eckhardt 
   3  *      generic SCSI package header file by
   4  *              Drew Eckhardt 
   5  *
   6  *      <drew@colorado.edu>
   7  *
   8  *       Modified by Eric Youngdale eric@tantalus.nrl.navy.mil to
   9  *       add scatter-gather, multiple outstanding request, and other
  10  *       enhancements.
  11  */
  12 
  13 #ifndef _SCSI_H
  14 #define _SCSI_H
  15 
  16 /*
  17         $Header: /usr/src/linux/kernel/blk_drv/scsi/RCS/scsi.h,v 1.3 1993/09/24 12:20:33 drew Exp $
  18 
  19         For documentation on the OPCODES, MESSAGES, and SENSE values,
  20         please consult the SCSI standard.
  21 
  22 */
  23 
  24 /*
  25         SCSI opcodes
  26 */
  27 
  28 #define TEST_UNIT_READY         0x00
  29 #define REZERO_UNIT             0x01
  30 #define REQUEST_SENSE           0x03
  31 #define FORMAT_UNIT             0x04
  32 #define READ_BLOCK_LIMITS       0x05
  33 #define REASSIGN_BLOCKS         0x07
  34 #define READ_6                  0x08
  35 #define WRITE_6                 0x0a
  36 #define SEEK_6                  0x0b
  37 #define READ_REVERSE            0x0f
  38 #define WRITE_FILEMARKS         0x10
  39 #define SPACE                   0x11
  40 #define INQUIRY                 0x12
  41 #define RECOVER_BUFFERED_DATA   0x14
  42 #define MODE_SELECT             0x15
  43 #define RESERVE                 0x16
  44 #define RELEASE                 0x17
  45 #define COPY                    0x18
  46 #define ERASE                   0x19
  47 #define MODE_SENSE              0x1a
  48 #define START_STOP              0x1b
  49 #define RECEIVE_DIAGNOSTIC      0x1c
  50 #define SEND_DIAGNOSTIC         0x1d
  51 #define ALLOW_MEDIUM_REMOVAL    0x1e
  52 
  53 #define READ_CAPACITY           0x25
  54 #define READ_10                 0x28
  55 #define WRITE_10                0x2a
  56 #define SEEK_10                 0x2b
  57 #define WRITE_VERIFY            0x2e
  58 #define VERIFY                  0x2f
  59 #define SEARCH_HIGH             0x30
  60 #define SEARCH_EQUAL            0x31
  61 #define SEARCH_LOW              0x32
  62 #define SET_LIMITS              0x33
  63 #define PRE_FETCH               0x34
  64 #define READ_POSITION           0x34
  65 #define SYNCHRONIZE_CACHE       0x35
  66 #define LOCK_UNLOCK_CACHE       0x36
  67 #define READ_DEFECT_DATA        0x37
  68 #define COMPARE                 0x39
  69 #define COPY_VERIFY             0x3a
  70 #define WRITE_BUFFER            0x3b
  71 #define READ_BUFFER             0x3c
  72 #define READ_LONG               0x3e
  73 #define CHANGE_DEFINITION       0x40
  74 #define LOG_SELECT              0x4c
  75 #define LOG_SENSE               0x4d
  76 #define MODE_SELECT_10          0x55
  77 #define MODE_SENSE_10           0x5a
  78 
  79 extern volatile int in_scan_scsis;
  80 extern const unsigned char scsi_command_size[8];
  81 #define COMMAND_SIZE(opcode) scsi_command_size[((opcode) >> 5) & 7]
  82 
  83 /*
  84         MESSAGE CODES
  85 */
  86 
  87 #define COMMAND_COMPLETE        0x00
  88 #define EXTENDED_MESSAGE        0x01
  89 #define         EXTENDED_MODIFY_DATA_POINTER    0x00
  90 #define         EXTENDED_SDTR                   0x01
  91 #define         EXTENDED_EXTENDED_IDENTIFY      0x02    /* SCSI-I only */
  92 #define         EXTENDED_WDTR                   0x03
  93 #define SAVE_POINTERS           0x02
  94 #define RESTORE_POINTERS        0x03
  95 #define DISCONNECT              0x04
  96 #define INITIATOR_ERROR         0x05
  97 #define ABORT                   0x06
  98 #define MESSAGE_REJECT          0x07
  99 #define NOP                     0x08
 100 #define MSG_PARITY_ERROR        0x09
 101 #define LINKED_CMD_COMPLETE     0x0a
 102 #define LINKED_FLG_CMD_COMPLETE 0x0b
 103 #define BUS_DEVICE_RESET        0x0c
 104 
 105 #define INITIATE_RECOVERY       0x0f                    /* SCSI-II only */
 106 #define RELEASE_RECOVERY        0x10                    /* SCSI-II only */
 107 
 108 #define SIMPLE_QUEUE_TAG        0x20
 109 #define HEAD_OF_QUEUE_TAG       0x21
 110 #define ORDERED_QUEUE_TAG       0x22
 111 
 112 #define IDENTIFY_BASE           0x80
 113 #define IDENTIFY(can_disconnect, lun)   (IDENTIFY_BASE |\
 114                                          ((can_disconnect) ?  0x40 : 0) |\
 115                                          ((lun) & 0x07)) 
 116 
 117                                  
 118 /*
 119         Status codes
 120 */
 121 
 122 #define GOOD                    0x00
 123 #define CHECK_CONDITION         0x01
 124 #define CONDITION_GOOD          0x02
 125 #define BUSY                    0x04
 126 #define INTERMEDIATE_GOOD       0x08
 127 #define INTERMEDIATE_C_GOOD     0x0a
 128 #define RESERVATION_CONFLICT    0x0c
 129 
 130 #define STATUS_MASK             0x1e
 131         
 132 /*
 133         the return of the status word will be in the following format :
 134         The low byte is the status returned by the SCSI command, 
 135         with vendor specific bits masked.
 136 
 137         The next byte is the message which followed the SCSI status.
 138         This allows a stos to be used, since the Intel is a little
 139         endian machine.
 140 
 141         The final byte is a host return code, which is one of the following.
 142 
 143         IE 
 144         lsb             msb
 145         status  msg     host code       
 146 
 147         Our errors returned by OUR driver, NOT SCSI message.  Or'd with
 148         SCSI message passed back to driver <IF any>.
 149 */
 150 
 151 /*      NO error                                                        */
 152 #define DID_OK                  0x00
 153 /*      Couldn't connect before timeout period                          */
 154 #define DID_NO_CONNECT          0x01
 155 /*      BUS stayed busy through time out period                         */
 156 #define DID_BUS_BUSY            0x02
 157 /*      TIMED OUT for other reason                                      */
 158 #define DID_TIME_OUT            0x03
 159 /*      BAD target.                                                     */
 160 #define DID_BAD_TARGET          0x04
 161 /*      Told to abort for some other reason                             */
 162 #define DID_ABORT               0x05
 163 /*
 164         Parity error
 165 */
 166 #define DID_PARITY              0x06
 167 /*
 168         Internal error
 169 */
 170 #define DID_ERROR               0x07    
 171 /*
 172         Reset by somebody.
 173 */
 174 #define DID_RESET               0x08
 175 /*
 176         Got an interrupt we weren't expecting.
 177 */
 178 #define DID_BAD_INTR            0x09
 179 
 180 /*
 181         Driver status
 182 */ 
 183 #define DRIVER_OK               0x00
 184 
 185 /*
 186         These indicate the error that occured, and what is available.
 187 */
 188 
 189 #define DRIVER_BUSY             0x01
 190 #define DRIVER_SOFT             0x02
 191 #define DRIVER_MEDIA            0x03
 192 #define DRIVER_ERROR            0x04    
 193 
 194 #define DRIVER_INVALID          0x05
 195 #define DRIVER_TIMEOUT          0x06
 196 #define DRIVER_HARD             0x07
 197 
 198 #define SUGGEST_RETRY           0x10
 199 #define SUGGEST_ABORT           0x20 
 200 #define SUGGEST_REMAP           0x30
 201 #define SUGGEST_DIE             0x40
 202 #define SUGGEST_SENSE           0x80
 203 #define SUGGEST_IS_OK           0xff
 204 
 205 #define DRIVER_SENSE            0x08
 206 
 207 #define DRIVER_MASK 0x0f
 208 #define SUGGEST_MASK 0xf0
 209 
 210 /*
 211 
 212         SENSE KEYS
 213 */
 214 
 215 #define NO_SENSE                0x00
 216 #define RECOVERED_ERROR         0x01
 217 #define NOT_READY               0x02
 218 #define MEDIUM_ERROR            0x03
 219 #define HARDWARE_ERROR          0x04
 220 #define ILLEGAL_REQUEST         0x05
 221 #define UNIT_ATTENTION          0x06
 222 #define DATA_PROTECT            0x07
 223 #define BLANK_CHECK             0x08
 224 #define COPY_ABORTED            0x0a
 225 #define ABORTED_COMMAND         0x0b
 226 #define VOLUME_OVERFLOW         0x0d
 227 #define MISCOMPARE              0x0e
 228 
 229 
 230 /*
 231         DEVICE TYPES
 232 
 233 */
 234 
 235 #define TYPE_DISK       0x00
 236 #define TYPE_TAPE       0x01
 237 #define TYPE_WORM       0x04    /* Treated as ROM by our system */
 238 #define TYPE_ROM        0x05
 239 #define TYPE_MOD        0x07  /* Magneto-optical disk - treated as TYPE_DISK */
 240 #define TYPE_NO_LUN     0x7f
 241 
 242 
 243 #define MAX_COMMAND_SIZE 12
 244 /*
 245         SCSI command sets
 246 
 247 */
 248 
 249 #define SCSI_UNKNOWN    0
 250 #define SCSI_1          1
 251 #define SCSI_1_CCS      2
 252 #define SCSI_2          3
 253 
 254 /*
 255         Every SCSI command starts with a one byte OP-code.
 256         The next byte's high three bits are the LUN of the
 257         device.  Any multi-byte quantities are stored high byte
 258         first, and may have a 5 bit MSB in the same byte
 259         as the LUN.
 260 */
 261 
 262 
 263 /*
 264         The scsi_device struct contains what we know about each given scsi
 265         device.
 266 */
 267 
 268 typedef struct scsi_device {
 269         struct scsi_device * next; /* Used for linked list */
 270         unsigned char id, lun;
 271         int attached;          /* # of high level drivers attached to this */
 272         int access_count;       /* Count of open channels/mounts */
 273         struct wait_queue * device_wait;  /* Used to wait if device is busy */
 274         struct Scsi_Host * host;
 275         void (*scsi_request_fn)(void); /* Used to jumpstart things after an ioctl */
 276         void *hostdata;                   /* available to low-level driver */
 277         char type;
 278         char scsi_level;
 279         unsigned writeable:1;
 280         unsigned removable:1; 
 281         unsigned random:1;
 282         unsigned changed:1;     /* Data invalid due to media change */
 283         unsigned busy:1;        /* Used to prevent races */
 284         unsigned lockable:1;    /* Able to prevent media removal */
 285         unsigned borken:1;      /* Tell the Seagate driver to be 
 286                                    painfully slow on this device */ 
 287         unsigned tagged_supported:1; /* Supports SCSI-II tagged queuing */
 288         unsigned tagged_queue:1;   /*SCSI-II tagged queuing enabled */
 289         unsigned disconnect:1;     /* can disconnect */
 290         unsigned soft_reset:1;          /* Uses soft reset option */
 291         unsigned char current_tag; /* current tag */
 292         unsigned sync:1;        /* Negotiate for sync transfers */
 293         unsigned char sync_min_period;  /* Not less than this period */
 294         unsigned char sync_max_offset;  /* Not greater than this offset */
 295 } Scsi_Device;
 296 /*
 297         Use these to separate status msg and our bytes
 298 */
 299 
 300 #define status_byte(result) (((result) >> 1) & 0xf)
 301 #define msg_byte(result) (((result) >> 8) & 0xff)
 302 #define host_byte(result) (((result) >> 16) & 0xff)
 303 #define driver_byte(result) (((result) >> 24) & 0xff)
 304 #define suggestion(result) (driver_byte(result) & SUGGEST_MASK)
 305 
 306 #define sense_class(sense) (((sense) >> 4) & 0x7)
 307 #define sense_error(sense) ((sense) & 0xf)
 308 #define sense_valid(sense) ((sense) & 0x80);
 309 
 310 /*
 311         These are the SCSI devices available on the system.
 312 */
 313 
 314 extern Scsi_Device * scsi_devices;
 315 /*
 316         Initializes all SCSI devices.  This scans all scsi busses.
 317 */
 318 
 319 extern unsigned long scsi_dev_init (unsigned long, unsigned long);
 320 
 321 struct scatterlist {
 322      char *  address; /* Location data is to be transferred to */
 323      char * alt_address; /* Location of actual if address is a 
 324                             dma indirect buffer.  NULL otherwise */
 325      unsigned int length;
 326      };
 327 
 328 #define ISA_DMA_THRESHOLD (0x00ffffff)
 329 #define CONTIGUOUS_BUFFERS(X,Y) ((X->b_data+X->b_size) == Y->b_data)
 330 
 331 
 332 /*
 333  * These are the return codes for the abort and reset functions.  The mid-level
 334  * code uses these to decide what to do next.  Each of the low level abort
 335  * and reset functions must correctly indicate what it has done.
 336  */
 337 
 338 /* We did not do anything.  Wait
 339    some more for this command to complete, and if this does not work, try
 340    something more serious. */ 
 341 #define SCSI_ABORT_SNOOZE 0
 342 
 343 /* This means that we were able to abort the command.  We have already
 344    called the mid-level done function, and do not expect an interrupt that will
 345    lead to another call to the mid-level done function for this command */
 346 #define SCSI_ABORT_SUCCESS 1
 347 
 348 /* We called for an abort of this command, and we should get an interrupt 
 349    when this succeeds.  Thus we should not restore the timer for this
 350    command in the mid-level abort function. */
 351 #define SCSI_ABORT_PENDING 2
 352 
 353 /* Unable to abort - command is currently on the bus.  Grin and bear it. */
 354 #define SCSI_ABORT_BUSY 3
 355 
 356 /* The command is not active in the low level code. Command probably
 357    finished. */
 358 #define SCSI_ABORT_NOT_RUNNING 4
 359 
 360 /* Something went wrong.  The low level driver will indicate the correct
 361  error condition when it calls scsi_done, so the mid-level abort function
 362  can simply wait until this comes through */
 363 #define SCSI_ABORT_ERROR 5
 364 
 365 /* We do not know how to reset the bus, or we do not want to.  Bummer.
 366    Anyway, just wait a little more for the command in question, and hope that
 367    it eventually finishes.  If it never finishes, the SCSI device could
 368    hang, so use this with caution. */
 369 #define SCSI_RESET_SNOOZE 0
 370 
 371 /* We do not know how to reset the bus, or we do not want to.  Bummer.
 372    We have given up on this ever completing.  The mid-level code will
 373    request sense information to decide how to proceed from here. */
 374 #define SCSI_RESET_PUNT 1
 375 
 376 /* This means that we were able to reset the bus.  We have restarted all of
 377    the commands that should be restarted, and we should be able to continue
 378    on normally from here.  We do not expect any interrupts that will return
 379    DID_RESET to any of the other commands in the host_queue, and the mid-level
 380    code does not need to do anything special to keep the commands alive. */
 381 #define SCSI_RESET_SUCCESS 2
 382 
 383 /* We called for an reset of this bus, and we should get an interrupt 
 384    when this succeeds.  Each command should get it's own status
 385    passed up to scsi_done, but this has not happened yet. */
 386 #define SCSI_RESET_PENDING 3
 387 
 388 /* We did a reset, but do not expect an interrupt to signal DID_RESET.
 389    This tells the upper level code to request the sense info, and this
 390    should keep the command alive. */
 391 #define SCSI_RESET_WAKEUP 4
 392 
 393 /* Something went wrong, and we do not know how to fix it. */
 394 #define SCSI_RESET_ERROR 5
 395 
 396 void *   scsi_malloc(unsigned int);
 397 int      scsi_free(void *, unsigned int);
 398 extern unsigned int dma_free_sectors;   /* How much room do we have left */
 399 extern unsigned int need_isa_buffer;   /* True if some devices need indirection
 400                                  buffers */
 401 
 402 /*
 403         The Scsi_Cmnd structure is used by scsi.c internally, and for communication with
 404         low level drivers that support multiple outstanding commands.
 405 */
 406 typedef struct scsi_pointer {
 407   char * ptr;                     /* data pointer */
 408   int this_residual;              /* left in this buffer */
 409   struct scatterlist *buffer;     /* which buffer */
 410   int buffers_residual;           /* how many buffers left */
 411 
 412   volatile int Status;
 413   volatile int Message;
 414   volatile int have_data_in;
 415   volatile int sent_command;
 416   volatile int phase;
 417 } Scsi_Pointer;
 418 
 419 typedef struct scsi_cmnd {
 420         struct Scsi_Host * host;
 421         Scsi_Device * device;
 422         unsigned char target, lun;
 423         struct scsi_cmnd *next, *prev;  
 424 
 425 /* These elements define the operation we are about to perform */
 426         unsigned char cmnd[12];
 427         unsigned request_bufflen; /* Actual request size */
 428 
 429         void * request_buffer;  /* Actual requested buffer */
 430 
 431 /* These elements define the operation we ultimately want to perform */
 432         unsigned char data_cmnd[12];
 433         unsigned short old_use_sg;  /* We save  use_sg here when requesting
 434                                        sense info */
 435         unsigned short use_sg;  /* Number of pieces of scatter-gather */
 436         unsigned short sglist_len;  /* size of malloc'd scatter-gather list */
 437         unsigned short abort_reason;  /* If the mid-level code requests an
 438                                          abort, this is the reason. */
 439         unsigned bufflen;     /* Size of data buffer */
 440         void *buffer;   /* Data buffer */
 441 
 442         unsigned underflow;     /* Return error if less than this amount is 
 443                                    transfered */
 444 
 445         unsigned transfersize;  /* How much we are guaranteed to transfer with
 446                                    each SCSI transfer (ie, between disconnect /
 447                                    reconnects.   Probably == sector size */
 448         
 449         
 450         
 451         struct request request;  /* A copy of the command we are working on*/
 452 
 453         unsigned char sense_buffer[16];  /* Sense for this command, if needed*/
 454 
 455 
 456         int retries;
 457         int allowed;
 458         int timeout_per_command, timeout_total, timeout;
 459 /*
 460  *      We handle the timeout differently if it happens when a reset, 
 461  *      abort, etc are in process. 
 462  */
 463 
 464         unsigned volatile char internal_timeout;
 465 
 466         unsigned flags;
 467                 
 468 /* These variables are for the cdrom only.  Once we have variable size buffers
 469    in the buffer cache, they will go away. */
 470         int this_count; 
 471 /* End of special cdrom variables */
 472         
 473         /* Low-level done function - can be used by low-level driver to point
 474          to completion function.  Not used by mid/upper level code. */
 475         void (*scsi_done)(struct scsi_cmnd *);  
 476         void (*done)(struct scsi_cmnd *);  /* Mid-level done function */
 477 
 478 /* The following fields can be written to by the host specific code. 
 479    Everything else should be left alone. */
 480 
 481         Scsi_Pointer SCp;   /* Scratchpad used by some host adapters */
 482 
 483         unsigned char * host_scribble; /* The host adapter is allowed to
 484                                           call scsi_malloc and get some memory
 485                                           and hang it here.  The host adapter
 486                                           is also expected to call scsi_free
 487                                           to release this memory.  (The memory
 488                                           obtained by scsi_malloc is guaranteed
 489                                           to be at an address < 16Mb). */
 490 
 491         int result;                   /* Status code from lower level driver */
 492 
 493         unsigned char tag;              /* SCSI-II queued command tag */
 494         unsigned long pid;              /* Process ID, starts at 0 */
 495         } Scsi_Cmnd;             
 496 
 497 /*
 498         scsi_abort aborts the current command that is executing on host host.
 499         The error code, if non zero is returned in the host byte, otherwise 
 500         DID_ABORT is returned in the hostbyte.
 501 */
 502 
 503 extern int scsi_abort (Scsi_Cmnd *, int code);
 504 
 505 extern void scsi_do_cmd (Scsi_Cmnd *, const void *cmnd ,
 506                   void *buffer, unsigned bufflen, void (*done)(struct scsi_cmnd *),
 507                   int timeout, int retries);
 508 
 509 
 510 extern Scsi_Cmnd * allocate_device(struct request **, Scsi_Device *, int);
 511 
 512 extern Scsi_Cmnd * request_queueable(struct request *, Scsi_Device *);
 513 extern int scsi_reset (Scsi_Cmnd *);
 514 
 515 extern int max_scsi_hosts;
 516 
 517 #if defined(MAJOR_NR) && (MAJOR_NR != SCSI_TAPE_MAJOR)
 518 static Scsi_Cmnd * end_scsi_request(Scsi_Cmnd * SCpnt, int uptodate, int sectors)
     /* [previous][next][first][last][top][bottom][index][help] */
 519 {
 520         struct request * req;
 521         struct buffer_head * bh;
 522 
 523         req = &SCpnt->request;
 524         req->errors = 0;
 525         if (!uptodate) {
 526                 printk(DEVICE_NAME " I/O error: dev %04x, sector %lu\n",
 527                        req->dev,req->sector);
 528         }
 529 
 530         do {
 531           if ((bh = req->bh) != NULL) {
 532             req->bh = bh->b_reqnext;
 533             req->nr_sectors -= bh->b_size >> 9;
 534             req->sector += bh->b_size >> 9;
 535             bh->b_reqnext = NULL;
 536             bh->b_uptodate = uptodate;
 537             unlock_buffer(bh);
 538             sectors -= bh->b_size >> 9;
 539             if ((bh = req->bh) != NULL) {
 540               req->current_nr_sectors = bh->b_size >> 9;
 541               if (req->nr_sectors < req->current_nr_sectors) {
 542                 req->nr_sectors = req->current_nr_sectors;
 543                 printk("end_scsi_request: buffer-list destroyed\n");
 544               }
 545             }
 546           }
 547         } while(sectors && bh);
 548         if (req->bh){
 549           req->buffer = bh->b_data;
 550           return SCpnt;
 551         };
 552         DEVICE_OFF(req->dev);
 553         if (req->sem != NULL) {
 554                 up(req->sem);
 555         }
 556         req->dev = -1;
 557         wake_up(&SCpnt->device->device_wait);
 558         return NULL;
 559 }
 560 
 561 
 562 /* This is just like INIT_REQUEST, but we need to be aware of the fact
 563    that an interrupt may start another request, so we run this with interrupts
 564    turned off */
 565 
 566 #define INIT_SCSI_REQUEST \
 567         if (!CURRENT) {\
 568                 CLEAR_INTR; \
 569                 sti();   \
 570                 return; \
 571         } \
 572         if (MAJOR(CURRENT->dev) != MAJOR_NR) \
 573                 panic(DEVICE_NAME ": request list destroyed"); \
 574         if (CURRENT->bh) { \
 575                 if (!CURRENT->bh->b_lock) \
 576                         panic(DEVICE_NAME ": block not locked"); \
 577         }
 578 #endif
 579 
 580 #define SCSI_SLEEP(QUEUE, CONDITION) {                          \
 581         if (CONDITION) {                                        \
 582                 struct wait_queue wait = { current, NULL};      \
 583                 add_wait_queue(QUEUE, &wait);                   \
 584 sleep_repeat:                                                   \
 585                 current->state = TASK_UNINTERRUPTIBLE;          \
 586                 if (CONDITION) {                                \
 587                         schedule();                             \
 588                         goto sleep_repeat;                      \
 589                 }                                               \
 590                 remove_wait_queue(QUEUE, &wait);                \
 591                 current->state = TASK_RUNNING;                  \
 592         }; }
 593 
 594 #endif

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