drivers/scsi/ide-scsi.c

   1 /*
   2  * linux/drivers/scsi/ide-scsi.c        Version 0.9             Jul   4, 1999
   3  *
   4  * Copyright (C) 1996 - 1999 Gadi Oxman <gadio@netvision.net.il>
   5  */
   6
   7 /*
   8  * Emulation of a SCSI host adapter for IDE ATAPI devices.
   9  *
  10  * With this driver, one can use the Linux SCSI drivers instead of the
  11  * native IDE ATAPI drivers.
  12  *
  13  * Ver 0.1   Dec  3 96   Initial version.
  14  * Ver 0.2   Jan 26 97   Fixed bug in cleanup_module() and added emulation
  15  *                        of MODE_SENSE_6/MODE_SELECT_6 for cdroms. Thanks
  16  *                        to Janos Farkas for pointing this out.
  17  *                       Avoid using bitfields in structures for m68k.
  18  *                       Added Scatter/Gather and DMA support.
  19  * Ver 0.4   Dec  7 97   Add support for ATAPI PD/CD drives.
  20  *                       Use variable timeout for each command.
  21  * Ver 0.5   Jan  2 98   Fix previous PD/CD support.
  22  *                       Allow disabling of SCSI-6 to SCSI-10 transformation.
  23  * Ver 0.6   Jan 27 98   Allow disabling of SCSI command translation layer
  24  *                        for access through /dev/sg.
  25  *                       Fix MODE_SENSE_6/MODE_SELECT_6/INQUIRY translation.
  26  * Ver 0.7   Dec 04 98   Ignore commands where lun != 0 to avoid multiple
  27  *                        detection of devices with CONFIG_SCSI_MULTI_LUN
  28  * Ver 0.8   Feb 05 99   Optical media need translation too. Reverse 0.7.
  29  * Ver 0.9   Jul 04 99   Fix a bug in SG_SET_TRANSFORM.
  30  * Ver 0.91  Jun 10 02   Fix "off by one" error in transforms
  31  * Ver 0.92  Dec 31 02   Implement new SCSI mid level API
  32  */
  33
  34 #define IDESCSI_VERSION "0.92"
  35
  36 #include <linux/module.h>
  37 #include <linux/types.h>
  38 #include <linux/string.h>
  39 #include <linux/kernel.h>
  40 #include <linux/mm.h>
  41 #include <linux/ioport.h>
  42 #include <linux/blkdev.h>
  43 #include <linux/errno.h>
  44 #include <linux/hdreg.h>
  45 #include <linux/slab.h>
  46 #include <linux/ide.h>
  47 #include <linux/scatterlist.h>
  48 #include <linux/delay.h>
  49 #include <linux/mutex.h>
  50 #include <linux/bitops.h>
  51
  52 #include <asm/io.h>
  53 #include <asm/uaccess.h>
  54
  55 #include <scsi/scsi.h>
  56 #include <scsi/scsi_cmnd.h>
  57 #include <scsi/scsi_device.h>
  58 #include <scsi/scsi_host.h>
  59 #include <scsi/scsi_tcq.h>
  60 #include <scsi/sg.h>
  61
  62 #define IDESCSI_DEBUG_LOG               0
  63
  64 typedef struct idescsi_pc_s {
  65         u8 c[12];                               /* Actual packet bytes */
  66         int request_transfer;                   /* Bytes to transfer */
  67         int actually_transferred;               /* Bytes actually transferred */
  68         int buffer_size;                        /* Size of our data buffer */
  69         struct request *rq;                     /* The corresponding request */
  70         u8 *buffer;                             /* Data buffer */
  71         u8 *current_position;                   /* Pointer into the above buffer */
  72         struct scatterlist *sg;                 /* Scatter gather table */
  73         unsigned int sg_cnt;                    /* Number of entries in sg */
  74         int b_count;                            /* Bytes transferred from current entry */
  75         struct scsi_cmnd *scsi_cmd;             /* SCSI command */
  76         void (*done)(struct scsi_cmnd *);       /* Scsi completion routine */
  77         unsigned long flags;                    /* Status/Action flags */
  78         unsigned long timeout;                  /* Command timeout */
  79 } idescsi_pc_t;
  80
  81 /*
  82  *      Packet command status bits.
  83  */
  84 #define PC_DMA_IN_PROGRESS              0       /* 1 while DMA in progress */
  85 #define PC_WRITING                      1       /* Data direction */
  86 #define PC_TIMEDOUT                     3       /* command timed out */
  87 #define PC_DMA_OK                       4       /* Use DMA */
  88
  89 /*
  90  *      SCSI command transformation layer
  91  */
  92 #define IDESCSI_SG_TRANSFORM            1       /* /dev/sg transformation */
  93
  94 /*
  95  *      Log flags
  96  */
  97 #define IDESCSI_LOG_CMD                 0       /* Log SCSI commands */
  98
  99 typedef struct ide_scsi_obj {
 100         ide_drive_t             *drive;
 101         ide_driver_t            *driver;
 102         struct gendisk          *disk;
 103         struct Scsi_Host        *host;
 104
 105         idescsi_pc_t *pc;                       /* Current packet command */
 106         unsigned long flags;                    /* Status/Action flags */
 107         unsigned long transform;                /* SCSI cmd translation layer */
 108         unsigned long log;                      /* log flags */
 109 } idescsi_scsi_t;
 110
 111 static DEFINE_MUTEX(idescsi_ref_mutex);
 112 static int idescsi_nocd;                        /* Set by module param to skip cd */
 113
 114 #define ide_scsi_g(disk) \
 115         container_of((disk)->private_data, struct ide_scsi_obj, driver)
 116
 117 static struct ide_scsi_obj *ide_scsi_get(struct gendisk *disk)
 118 {
 119         struct ide_scsi_obj *scsi = NULL;
 120
 121         mutex_lock(&idescsi_ref_mutex);
 122         scsi = ide_scsi_g(disk);
 123         if (scsi)
 124                 scsi_host_get(scsi->host);
 125         mutex_unlock(&idescsi_ref_mutex);
 126         return scsi;
 127 }
 128
 129 static void ide_scsi_put(struct ide_scsi_obj *scsi)
 130 {
 131         mutex_lock(&idescsi_ref_mutex);
 132         scsi_host_put(scsi->host);
 133         mutex_unlock(&idescsi_ref_mutex);
 134 }
 135
 136 static inline idescsi_scsi_t *scsihost_to_idescsi(struct Scsi_Host *host)
 137 {
 138         return (idescsi_scsi_t*) (&host[1]);
 139 }
 140
 141 static inline idescsi_scsi_t *drive_to_idescsi(ide_drive_t *ide_drive)
 142 {
 143         return scsihost_to_idescsi(ide_drive->driver_data);
 144 }
 145
 146 /*
 147  *      Per ATAPI device status bits.
 148  */
 149 #define IDESCSI_DRQ_INTERRUPT           0       /* DRQ interrupt device */
 150
 151 /*
 152  *      ide-scsi requests.
 153  */
 154 #define IDESCSI_PC_RQ                   90
 155
 156 static void idescsi_discard_data (ide_drive_t *drive, unsigned int bcount)
 157 {
 158         while (bcount--)
 159                 (void) HWIF(drive)->INB(IDE_DATA_REG);
 160 }
 161
 162 static void idescsi_output_zeros (ide_drive_t *drive, unsigned int bcount)
 163 {
 164         while (bcount--)
 165                 HWIF(drive)->OUTB(0, IDE_DATA_REG);
 166 }
 167
 168 /*
 169  *      PIO data transfer routines using the scatter gather table.
 170  */
 171 static void idescsi_input_buffers (ide_drive_t *drive, idescsi_pc_t *pc, unsigned int bcount)
 172 {
 173         int count;
 174         char *buf;
 175
 176         while (bcount) {
 177                 count = min(pc->sg->length - pc->b_count, bcount);
 178                 if (PageHighMem(sg_page(pc->sg))) {
 179                         unsigned long flags;
 180
 181                         local_irq_save(flags);
 182                         buf = kmap_atomic(sg_page(pc->sg), KM_IRQ0) +
 183                                         pc->sg->offset;
 184                         drive->hwif->atapi_input_bytes(drive,
 185                                                 buf + pc->b_count, count);
 186                         kunmap_atomic(buf - pc->sg->offset, KM_IRQ0);
 187                         local_irq_restore(flags);
 188                 } else {
 189                         buf = sg_virt(pc->sg);
 190                         drive->hwif->atapi_input_bytes(drive,
 191                                                 buf + pc->b_count, count);
 192                 }
 193                 bcount -= count; pc->b_count += count;
 194                 if (pc->b_count == pc->sg->length) {
 195                         if (!--pc->sg_cnt)
 196                                 break;
 197                         pc->sg = sg_next(pc->sg);
 198                         pc->b_count = 0;
 199                 }
 200         }
 201
 202         if (bcount) {
 203                 printk (KERN_ERR "ide-scsi: scatter gather table too small, discarding data\n");
 204                 idescsi_discard_data (drive, bcount);
 205         }
 206 }
 207
 208 static void idescsi_output_buffers (ide_drive_t *drive, idescsi_pc_t *pc, unsigned int bcount)
 209 {
 210         int count;
 211         char *buf;
 212
 213         while (bcount) {
 214                 count = min(pc->sg->length - pc->b_count, bcount);
 215                 if (PageHighMem(sg_page(pc->sg))) {
 216                         unsigned long flags;
 217
 218                         local_irq_save(flags);
 219                         buf = kmap_atomic(sg_page(pc->sg), KM_IRQ0) +
 220                                                 pc->sg->offset;
 221                         drive->hwif->atapi_output_bytes(drive,
 222                                                 buf + pc->b_count, count);
 223                         kunmap_atomic(buf - pc->sg->offset, KM_IRQ0);
 224                         local_irq_restore(flags);
 225                 } else {
 226                         buf = sg_virt(pc->sg);
 227                         drive->hwif->atapi_output_bytes(drive,
 228                                                 buf + pc->b_count, count);
 229                 }
 230                 bcount -= count; pc->b_count += count;
 231                 if (pc->b_count == pc->sg->length) {
 232                         if (!--pc->sg_cnt)
 233                                 break;
 234                         pc->sg = sg_next(pc->sg);
 235                         pc->b_count = 0;
 236                 }
 237         }
 238
 239         if (bcount) {
 240                 printk (KERN_ERR "ide-scsi: scatter gather table too small, padding with zeros\n");
 241                 idescsi_output_zeros (drive, bcount);
 242         }
 243 }
 244
 245 static void hexdump(u8 *x, int len)
 246 {
 247         int i;
 248
 249         printk("[ ");
 250         for (i = 0; i < len; i++)
 251                 printk("%x ", x[i]);
 252         printk("]\n");
 253 }
 254
 255 static int idescsi_check_condition(ide_drive_t *drive, struct request *failed_command)
 256 {
 257         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
 258         idescsi_pc_t   *pc;
 259         struct request *rq;
 260         u8             *buf;
 261
 262         /* stuff a sense request in front of our current request */
 263         pc = kzalloc(sizeof(idescsi_pc_t), GFP_ATOMIC);
 264         rq = kmalloc(sizeof(struct request), GFP_ATOMIC);
 265         buf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_ATOMIC);
 266         if (!pc || !rq || !buf) {
 267                 kfree(buf);
 268                 kfree(rq);
 269                 kfree(pc);
 270                 return -ENOMEM;
 271         }
 272         ide_init_drive_cmd(rq);
 273         rq->special = (char *) pc;
 274         pc->rq = rq;
 275         pc->buffer = buf;
 276         pc->c[0] = REQUEST_SENSE;
 277         pc->c[4] = pc->request_transfer = pc->buffer_size = SCSI_SENSE_BUFFERSIZE;
 278         rq->cmd_type = REQ_TYPE_SENSE;
 279         pc->timeout = jiffies + WAIT_READY;
 280         /* NOTE! Save the failed packet command in "rq->buffer" */
 281         rq->buffer = (void *) failed_command->special;
 282         pc->scsi_cmd = ((idescsi_pc_t *) failed_command->special)->scsi_cmd;
 283         if (test_bit(IDESCSI_LOG_CMD, &scsi->log)) {
 284                 printk ("ide-scsi: %s: queue cmd = ", drive->name);
 285                 hexdump(pc->c, 6);
 286         }
 287         rq->rq_disk = scsi->disk;
 288         return ide_do_drive_cmd(drive, rq, ide_preempt);
 289 }
 290
 291 static int idescsi_end_request(ide_drive_t *, int, int);
 292
 293 static ide_startstop_t
 294 idescsi_atapi_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
 295 {
 296         if (HWIF(drive)->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT))
 297                 /* force an abort */
 298                 HWIF(drive)->OUTB(WIN_IDLEIMMEDIATE,IDE_COMMAND_REG);
 299
 300         rq->errors++;
 301
 302         idescsi_end_request(drive, 0, 0);
 303
 304         return ide_stopped;
 305 }
 306
 307 static ide_startstop_t
 308 idescsi_atapi_abort(ide_drive_t *drive, struct request *rq)
 309 {
 310 #if IDESCSI_DEBUG_LOG
 311         printk(KERN_WARNING "idescsi_atapi_abort called for %lu\n",
 312                         ((idescsi_pc_t *) rq->special)->scsi_cmd->serial_number);
 313 #endif
 314         rq->errors |= ERROR_MAX;
 315
 316         idescsi_end_request(drive, 0, 0);
 317
 318         return ide_stopped;
 319 }
 320
 321 static int idescsi_end_request (ide_drive_t *drive, int uptodate, int nrsecs)
 322 {
 323         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
 324         struct request *rq = HWGROUP(drive)->rq;
 325         idescsi_pc_t *pc = (idescsi_pc_t *) rq->special;
 326         int log = test_bit(IDESCSI_LOG_CMD, &scsi->log);
 327         struct Scsi_Host *host;
 328         int errors = rq->errors;
 329         unsigned long flags;
 330
 331         if (!blk_special_request(rq) && !blk_sense_request(rq)) {
 332                 ide_end_request(drive, uptodate, nrsecs);
 333                 return 0;
 334         }
 335         ide_end_drive_cmd (drive, 0, 0);
 336         if (blk_sense_request(rq)) {
 337                 idescsi_pc_t *opc = (idescsi_pc_t *) rq->buffer;
 338                 if (log) {
 339                         printk ("ide-scsi: %s: wrap up check %lu, rst = ", drive->name, opc->scsi_cmd->serial_number);
 340                         hexdump(pc->buffer,16);
 341                 }
 342                 memcpy((void *) opc->scsi_cmd->sense_buffer, pc->buffer, SCSI_SENSE_BUFFERSIZE);
 343                 kfree(pc->buffer);
 344                 kfree(pc);
 345                 kfree(rq);
 346                 pc = opc;
 347                 rq = pc->rq;
 348                 pc->scsi_cmd->result = (CHECK_CONDITION << 1) |
 349                                         ((test_bit(PC_TIMEDOUT, &pc->flags)?DID_TIME_OUT:DID_OK) << 16);
 350         } else if (test_bit(PC_TIMEDOUT, &pc->flags)) {
 351                 if (log)
 352                         printk (KERN_WARNING "ide-scsi: %s: timed out for %lu\n",
 353                                         drive->name, pc->scsi_cmd->serial_number);
 354                 pc->scsi_cmd->result = DID_TIME_OUT << 16;
 355         } else if (errors >= ERROR_MAX) {
 356                 pc->scsi_cmd->result = DID_ERROR << 16;
 357                 if (log)
 358                         printk ("ide-scsi: %s: I/O error for %lu\n", drive->name, pc->scsi_cmd->serial_number);
 359         } else if (errors) {
 360                 if (log)
 361                         printk ("ide-scsi: %s: check condition for %lu\n", drive->name, pc->scsi_cmd->serial_number);
 362                 if (!idescsi_check_condition(drive, rq))
 363                         /* we started a request sense, so we'll be back, exit for now */
 364                         return 0;
 365                 pc->scsi_cmd->result = (CHECK_CONDITION << 1) | (DID_OK << 16);
 366         } else {
 367                 pc->scsi_cmd->result = DID_OK << 16;
 368         }
 369         host = pc->scsi_cmd->device->host;
 370         spin_lock_irqsave(host->host_lock, flags);
 371         pc->done(pc->scsi_cmd);
 372         spin_unlock_irqrestore(host->host_lock, flags);
 373         kfree(pc);
 374         kfree(rq);
 375         scsi->pc = NULL;
 376         return 0;
 377 }
 378
 379 static inline unsigned long get_timeout(idescsi_pc_t *pc)
 380 {
 381         return max_t(unsigned long, WAIT_CMD, pc->timeout - jiffies);
 382 }
 383
 384 static int idescsi_expiry(ide_drive_t *drive)
 385 {
 386         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
 387         idescsi_pc_t   *pc   = scsi->pc;
 388
 389 #if IDESCSI_DEBUG_LOG
 390         printk(KERN_WARNING "idescsi_expiry called for %lu at %lu\n", pc->scsi_cmd->serial_number, jiffies);
 391 #endif
 392         set_bit(PC_TIMEDOUT, &pc->flags);
 393
 394         return 0;                                       /* we do not want the ide subsystem to retry */
 395 }
 396
 397 /*
 398  *      Our interrupt handler.
 399  */
 400 static ide_startstop_t idescsi_pc_intr (ide_drive_t *drive)
 401 {
 402         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
 403         idescsi_pc_t *pc=scsi->pc;
 404         struct request *rq = pc->rq;
 405         atapi_bcount_t bcount;
 406         atapi_status_t status;
 407         atapi_ireason_t ireason;
 408         atapi_feature_t feature;
 409
 410         unsigned int temp;
 411
 412 #if IDESCSI_DEBUG_LOG
 413         printk (KERN_INFO "ide-scsi: Reached idescsi_pc_intr interrupt handler\n");
 414 #endif /* IDESCSI_DEBUG_LOG */
 415
 416         if (test_bit(PC_TIMEDOUT, &pc->flags)){
 417 #if IDESCSI_DEBUG_LOG
 418                 printk(KERN_WARNING "idescsi_pc_intr: got timed out packet  %lu at %lu\n",
 419                                 pc->scsi_cmd->serial_number, jiffies);
 420 #endif
 421                 /* end this request now - scsi should retry it*/
 422                 idescsi_end_request (drive, 1, 0);
 423                 return ide_stopped;
 424         }
 425         if (test_and_clear_bit (PC_DMA_IN_PROGRESS, &pc->flags)) {
 426 #if IDESCSI_DEBUG_LOG
 427                 printk ("ide-scsi: %s: DMA complete\n", drive->name);
 428 #endif /* IDESCSI_DEBUG_LOG */
 429                 pc->actually_transferred=pc->request_transfer;
 430                 (void) HWIF(drive)->ide_dma_end(drive);
 431         }
 432
 433         feature.all = 0;
 434         /* Clear the interrupt */
 435         status.all = HWIF(drive)->INB(IDE_STATUS_REG);
 436
 437         if (!status.b.drq) {
 438                 /* No more interrupts */
 439                 if (test_bit(IDESCSI_LOG_CMD, &scsi->log))
 440                         printk (KERN_INFO "Packet command completed, %d bytes transferred\n", pc->actually_transferred);
 441                 local_irq_enable_in_hardirq();
 442                 if (status.b.check)
 443                         rq->errors++;
 444                 idescsi_end_request (drive, 1, 0);
 445                 return ide_stopped;
 446         }
 447         bcount.b.low    = HWIF(drive)->INB(IDE_BCOUNTL_REG);
 448         bcount.b.high   = HWIF(drive)->INB(IDE_BCOUNTH_REG);
 449         ireason.all     = HWIF(drive)->INB(IDE_IREASON_REG);
 450
 451         if (ireason.b.cod) {
 452                 printk(KERN_ERR "ide-scsi: CoD != 0 in idescsi_pc_intr\n");
 453                 return ide_do_reset (drive);
 454         }
 455         if (ireason.b.io) {
 456                 temp = pc->actually_transferred + bcount.all;
 457                 if (temp > pc->request_transfer) {
 458                         if (temp > pc->buffer_size) {
 459                                 printk(KERN_ERR "ide-scsi: The scsi wants to "
 460                                         "send us more data than expected "
 461                                         "- discarding data\n");
 462                                 temp = pc->buffer_size - pc->actually_transferred;
 463                                 if (temp) {
 464                                         clear_bit(PC_WRITING, &pc->flags);
 465                                         if (pc->sg)
 466                                                 idescsi_input_buffers(drive, pc, temp);
 467                                         else
 468                                                 drive->hwif->atapi_input_bytes(drive, pc->current_position, temp);
 469                                         printk(KERN_ERR "ide-scsi: transferred %d of %d bytes\n", temp, bcount.all);
 470                                 }
 471                                 pc->actually_transferred += temp;
 472                                 pc->current_position += temp;
 473                                 idescsi_discard_data(drive, bcount.all - temp);
 474                                 ide_set_handler(drive, &idescsi_pc_intr, get_timeout(pc), idescsi_expiry);
 475                                 return ide_started;
 476                         }
 477 #if IDESCSI_DEBUG_LOG
 478                         printk (KERN_NOTICE "ide-scsi: The scsi wants to send us more data than expected - allowing transfer\n");
 479 #endif /* IDESCSI_DEBUG_LOG */
 480                 }
 481         }
 482         if (ireason.b.io) {
 483                 clear_bit(PC_WRITING, &pc->flags);
 484                 if (pc->sg)
 485                         idescsi_input_buffers(drive, pc, bcount.all);
 486                 else
 487                         HWIF(drive)->atapi_input_bytes(drive, pc->current_position, bcount.all);
 488         } else {
 489                 set_bit(PC_WRITING, &pc->flags);
 490                 if (pc->sg)
 491                         idescsi_output_buffers (drive, pc, bcount.all);
 492                 else
 493                         HWIF(drive)->atapi_output_bytes(drive, pc->current_position, bcount.all);
 494         }
 495         /* Update the current position */
 496         pc->actually_transferred += bcount.all;
 497         pc->current_position += bcount.all;
 498
 499         /* And set the interrupt handler again */
 500         ide_set_handler(drive, &idescsi_pc_intr, get_timeout(pc), idescsi_expiry);
 501         return ide_started;
 502 }
 503
 504 static ide_startstop_t idescsi_transfer_pc(ide_drive_t *drive)
 505 {
 506         ide_hwif_t *hwif = drive->hwif;
 507         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
 508         idescsi_pc_t *pc = scsi->pc;
 509         atapi_ireason_t ireason;
 510         ide_startstop_t startstop;
 511
 512         if (ide_wait_stat(&startstop,drive,DRQ_STAT,BUSY_STAT,WAIT_READY)) {
 513                 printk(KERN_ERR "ide-scsi: Strange, packet command "
 514                         "initiated yet DRQ isn't asserted\n");
 515                 return startstop;
 516         }
 517         ireason.all     = HWIF(drive)->INB(IDE_IREASON_REG);
 518         if (!ireason.b.cod || ireason.b.io) {
 519                 printk(KERN_ERR "ide-scsi: (IO,CoD) != (0,1) while "
 520                                 "issuing a packet command\n");
 521                 return ide_do_reset (drive);
 522         }
 523         BUG_ON(HWGROUP(drive)->handler != NULL);
 524         /* Set the interrupt routine */
 525         ide_set_handler(drive, &idescsi_pc_intr, get_timeout(pc), idescsi_expiry);
 526         /* Send the actual packet */
 527         drive->hwif->atapi_output_bytes(drive, scsi->pc->c, 12);
 528         if (test_bit (PC_DMA_OK, &pc->flags)) {
 529                 set_bit (PC_DMA_IN_PROGRESS, &pc->flags);
 530                 hwif->dma_start(drive);
 531         }
 532         return ide_started;
 533 }
 534
 535 static inline int idescsi_set_direction(idescsi_pc_t *pc)
 536 {
 537         switch (pc->c[0]) {
 538                 case READ_6: case READ_10: case READ_12:
 539                         clear_bit(PC_WRITING, &pc->flags);
 540                         return 0;
 541                 case WRITE_6: case WRITE_10: case WRITE_12:
 542                         set_bit(PC_WRITING, &pc->flags);
 543                         return 0;
 544                 default:
 545                         return 1;
 546         }
 547 }
 548
 549 static int idescsi_map_sg(ide_drive_t *drive, idescsi_pc_t *pc)
 550 {
 551         ide_hwif_t *hwif = drive->hwif;
 552         struct scatterlist *sg, *scsi_sg;
 553         int segments;
 554
 555         if (!pc->request_transfer || pc->request_transfer % 1024)
 556                 return 1;
 557
 558         if (idescsi_set_direction(pc))
 559                 return 1;
 560
 561         sg = hwif->sg_table;
 562         scsi_sg = scsi_sglist(pc->scsi_cmd);
 563         segments = scsi_sg_count(pc->scsi_cmd);
 564
 565         if (segments > hwif->sg_max_nents)
 566                 return 1;
 567
 568         hwif->sg_nents = segments;
 569         memcpy(sg, scsi_sg, sizeof(*sg) * segments);
 570
 571         return 0;
 572 }
 573
 574 /*
 575  *      Issue a packet command
 576  */
 577 static ide_startstop_t idescsi_issue_pc (ide_drive_t *drive, idescsi_pc_t *pc)
 578 {
 579         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
 580         ide_hwif_t *hwif = drive->hwif;
 581         atapi_feature_t feature;
 582         atapi_bcount_t bcount;
 583
 584         scsi->pc=pc;                                                    /* Set the current packet command */
 585         pc->actually_transferred=0;                                     /* We haven't transferred any data yet */
 586         pc->current_position=pc->buffer;
 587         bcount.all = min(pc->request_transfer, 63 * 1024);              /* Request to transfer the entire buffer at once */
 588
 589         feature.all = 0;
 590         if (drive->using_dma && !idescsi_map_sg(drive, pc)) {
 591                 hwif->sg_mapped = 1;
 592                 feature.b.dma = !hwif->dma_setup(drive);
 593                 hwif->sg_mapped = 0;
 594         }
 595
 596         SELECT_DRIVE(drive);
 597         if (IDE_CONTROL_REG)
 598                 HWIF(drive)->OUTB(drive->ctl, IDE_CONTROL_REG);
 599
 600         HWIF(drive)->OUTB(feature.all, IDE_FEATURE_REG);
 601         HWIF(drive)->OUTB(bcount.b.high, IDE_BCOUNTH_REG);
 602         HWIF(drive)->OUTB(bcount.b.low, IDE_BCOUNTL_REG);
 603
 604         if (feature.b.dma)
 605                 set_bit(PC_DMA_OK, &pc->flags);
 606
 607         if (test_bit(IDESCSI_DRQ_INTERRUPT, &scsi->flags)) {
 608                 BUG_ON(HWGROUP(drive)->handler != NULL);
 609                 ide_set_handler(drive, &idescsi_transfer_pc,
 610                                 get_timeout(pc), idescsi_expiry);
 611                 /* Issue the packet command */
 612                 HWIF(drive)->OUTB(WIN_PACKETCMD, IDE_COMMAND_REG);
 613                 return ide_started;
 614         } else {
 615                 /* Issue the packet command */
 616                 HWIF(drive)->OUTB(WIN_PACKETCMD, IDE_COMMAND_REG);
 617                 return idescsi_transfer_pc(drive);
 618         }
 619 }
 620
 621 /*
 622  *      idescsi_do_request is our request handling function.
 623  */
 624 static ide_startstop_t idescsi_do_request (ide_drive_t *drive, struct request *rq, sector_t block)
 625 {
 626 #if IDESCSI_DEBUG_LOG
 627         printk (KERN_INFO "dev: %s, cmd: %x, errors: %d\n", rq->rq_disk->disk_name,rq->cmd[0],rq->errors);
 628         printk (KERN_INFO "sector: %ld, nr_sectors: %ld, current_nr_sectors: %d\n",rq->sector,rq->nr_sectors,rq->current_nr_sectors);
 629 #endif /* IDESCSI_DEBUG_LOG */
 630
 631         if (blk_sense_request(rq) || blk_special_request(rq)) {
 632                 return idescsi_issue_pc (drive, (idescsi_pc_t *) rq->special);
 633         }
 634         blk_dump_rq_flags(rq, "ide-scsi: unsup command");
 635         idescsi_end_request (drive, 0, 0);
 636         return ide_stopped;
 637 }
 638
 639 #ifdef CONFIG_IDE_PROC_FS
 640 static void idescsi_add_settings(ide_drive_t *drive)
 641 {
 642         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
 643
 644 /*
 645  *                      drive   setting name    read/write      data type       min     max     mul_factor      div_factor      data pointer            set function
 646  */
 647         ide_add_setting(drive,  "bios_cyl",     SETTING_RW,     TYPE_INT,       0,      1023,   1,              1,              &drive->bios_cyl,       NULL);
 648         ide_add_setting(drive,  "bios_head",    SETTING_RW,     TYPE_BYTE,      0,      255,    1,              1,              &drive->bios_head,      NULL);
 649         ide_add_setting(drive,  "bios_sect",    SETTING_RW,     TYPE_BYTE,      0,      63,     1,              1,              &drive->bios_sect,      NULL);
 650         ide_add_setting(drive,  "transform",    SETTING_RW,     TYPE_INT,       0,      3,      1,              1,              &scsi->transform,       NULL);
 651         ide_add_setting(drive,  "log",          SETTING_RW,     TYPE_INT,       0,      1,      1,              1,              &scsi->log,             NULL);
 652 }
 653 #else
 654 static inline void idescsi_add_settings(ide_drive_t *drive) { ; }
 655 #endif
 656
 657 /*
 658  *      Driver initialization.
 659  */
 660 static void idescsi_setup (ide_drive_t *drive, idescsi_scsi_t *scsi)
 661 {
 662         if (drive->id && (drive->id->config & 0x0060) == 0x20)
 663                 set_bit (IDESCSI_DRQ_INTERRUPT, &scsi->flags);
 664         clear_bit(IDESCSI_SG_TRANSFORM, &scsi->transform);
 665 #if IDESCSI_DEBUG_LOG
 666         set_bit(IDESCSI_LOG_CMD, &scsi->log);
 667 #endif /* IDESCSI_DEBUG_LOG */
 668         idescsi_add_settings(drive);
 669 }
 670
 671 static void ide_scsi_remove(ide_drive_t *drive)
 672 {
 673         struct Scsi_Host *scsihost = drive->driver_data;
 674         struct ide_scsi_obj *scsi = scsihost_to_idescsi(scsihost);
 675         struct gendisk *g = scsi->disk;
 676
 677         scsi_remove_host(scsihost);
 678         ide_proc_unregister_driver(drive, scsi->driver);
 679
 680         ide_unregister_region(g);
 681
 682         drive->driver_data = NULL;
 683         g->private_data = NULL;
 684         put_disk(g);
 685
 686         ide_scsi_put(scsi);
 687 }
 688
 689 static int ide_scsi_probe(ide_drive_t *);
 690
 691 #ifdef CONFIG_IDE_PROC_FS
 692 static ide_proc_entry_t idescsi_proc[] = {
 693         { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL },
 694         { NULL, 0, NULL, NULL }
 695 };
 696 #endif
 697
 698 static ide_driver_t idescsi_driver = {
 699         .gen_driver = {
 700                 .owner          = THIS_MODULE,
 701                 .name           = "ide-scsi",
 702                 .bus            = &ide_bus_type,
 703         },
 704         .probe                  = ide_scsi_probe,
 705         .remove                 = ide_scsi_remove,
 706         .version                = IDESCSI_VERSION,
 707         .media                  = ide_scsi,
 708         .supports_dsc_overlap   = 0,
 709         .do_request             = idescsi_do_request,
 710         .end_request            = idescsi_end_request,
 711         .error                  = idescsi_atapi_error,
 712         .abort                  = idescsi_atapi_abort,
 713 #ifdef CONFIG_IDE_PROC_FS
 714         .proc                   = idescsi_proc,
 715 #endif
 716 };
 717
 718 static int idescsi_ide_open(struct inode *inode, struct file *filp)
 719 {
 720         struct gendisk *disk = inode->i_bdev->bd_disk;
 721         struct ide_scsi_obj *scsi;
 722
 723         if (!(scsi = ide_scsi_get(disk)))
 724                 return -ENXIO;
 725
 726         return 0;
 727 }
 728
 729 static int idescsi_ide_release(struct inode *inode, struct file *filp)
 730 {
 731         struct gendisk *disk = inode->i_bdev->bd_disk;
 732         struct ide_scsi_obj *scsi = ide_scsi_g(disk);
 733
 734         ide_scsi_put(scsi);
 735
 736         return 0;
 737 }
 738
 739 static int idescsi_ide_ioctl(struct inode *inode, struct file *file,
 740                         unsigned int cmd, unsigned long arg)
 741 {
 742         struct block_device *bdev = inode->i_bdev;
 743         struct ide_scsi_obj *scsi = ide_scsi_g(bdev->bd_disk);
 744         return generic_ide_ioctl(scsi->drive, file, bdev, cmd, arg);
 745 }
 746
 747 static struct block_device_operations idescsi_ops = {
 748         .owner          = THIS_MODULE,
 749         .open           = idescsi_ide_open,
 750         .release        = idescsi_ide_release,
 751         .ioctl          = idescsi_ide_ioctl,
 752 };
 753
 754 static int idescsi_slave_configure(struct scsi_device * sdp)
 755 {
 756         /* Configure detected device */
 757         sdp->use_10_for_rw = 1;
 758         sdp->use_10_for_ms = 1;
 759         scsi_adjust_queue_depth(sdp, MSG_SIMPLE_TAG, sdp->host->cmd_per_lun);
 760         return 0;
 761 }
 762
 763 static const char *idescsi_info (struct Scsi_Host *host)
 764 {
 765         return "SCSI host adapter emulation for IDE ATAPI devices";
 766 }
 767
 768 static int idescsi_ioctl (struct scsi_device *dev, int cmd, void __user *arg)
 769 {
 770         idescsi_scsi_t *scsi = scsihost_to_idescsi(dev->host);
 771
 772         if (cmd == SG_SET_TRANSFORM) {
 773                 if (arg)
 774                         set_bit(IDESCSI_SG_TRANSFORM, &scsi->transform);
 775                 else
 776                         clear_bit(IDESCSI_SG_TRANSFORM, &scsi->transform);
 777                 return 0;
 778         } else if (cmd == SG_GET_TRANSFORM)
 779                 return put_user(test_bit(IDESCSI_SG_TRANSFORM, &scsi->transform), (int __user *) arg);
 780         return -EINVAL;
 781 }
 782
 783 static int idescsi_queue (struct scsi_cmnd *cmd,
 784                 void (*done)(struct scsi_cmnd *))
 785 {
 786         struct Scsi_Host *host = cmd->device->host;
 787         idescsi_scsi_t *scsi = scsihost_to_idescsi(host);
 788         ide_drive_t *drive = scsi->drive;
 789         struct request *rq = NULL;
 790         idescsi_pc_t *pc = NULL;
 791
 792         if (!drive) {
 793                 scmd_printk (KERN_ERR, cmd, "drive not present\n");
 794                 goto abort;
 795         }
 796         scsi = drive_to_idescsi(drive);
 797         pc = kmalloc (sizeof (idescsi_pc_t), GFP_ATOMIC);
 798         rq = kmalloc (sizeof (struct request), GFP_ATOMIC);
 799         if (rq == NULL || pc == NULL) {
 800                 printk (KERN_ERR "ide-scsi: %s: out of memory\n", drive->name);
 801                 goto abort;
 802         }
 803
 804         memset (pc->c, 0, 12);
 805         pc->flags = 0;
 806         pc->rq = rq;
 807         memcpy (pc->c, cmd->cmnd, cmd->cmd_len);
 808         pc->buffer = NULL;
 809         pc->sg = scsi_sglist(cmd);
 810         pc->sg_cnt = scsi_sg_count(cmd);
 811         pc->b_count = 0;
 812         pc->request_transfer = pc->buffer_size = scsi_bufflen(cmd);
 813         pc->scsi_cmd = cmd;
 814         pc->done = done;
 815         pc->timeout = jiffies + cmd->timeout_per_command;
 816
 817         if (test_bit(IDESCSI_LOG_CMD, &scsi->log)) {
 818                 printk ("ide-scsi: %s: que %lu, cmd = ", drive->name, cmd->serial_number);
 819                 hexdump(cmd->cmnd, cmd->cmd_len);
 820                 if (memcmp(pc->c, cmd->cmnd, cmd->cmd_len)) {
 821                         printk ("ide-scsi: %s: que %lu, tsl = ", drive->name, cmd->serial_number);
 822                         hexdump(pc->c, 12);
 823                 }
 824         }
 825
 826         ide_init_drive_cmd (rq);
 827         rq->special = (char *) pc;
 828         rq->cmd_type = REQ_TYPE_SPECIAL;
 829         spin_unlock_irq(host->host_lock);
 830         rq->rq_disk = scsi->disk;
 831         (void) ide_do_drive_cmd (drive, rq, ide_end);
 832         spin_lock_irq(host->host_lock);
 833         return 0;
 834 abort:
 835         kfree (pc);
 836         kfree (rq);
 837         cmd->result = DID_ERROR << 16;
 838         done(cmd);
 839         return 0;
 840 }
 841
 842 static int idescsi_eh_abort (struct scsi_cmnd *cmd)
 843 {
 844         idescsi_scsi_t *scsi  = scsihost_to_idescsi(cmd->device->host);
 845         ide_drive_t    *drive = scsi->drive;
 846         int             busy;
 847         int             ret   = FAILED;
 848
 849         /* In idescsi_eh_abort we try to gently pry our command from the ide subsystem */
 850
 851         if (test_bit(IDESCSI_LOG_CMD, &scsi->log))
 852                 printk (KERN_WARNING "ide-scsi: abort called for %lu\n", cmd->serial_number);
 853
 854         if (!drive) {
 855                 printk (KERN_WARNING "ide-scsi: Drive not set in idescsi_eh_abort\n");
 856                 WARN_ON(1);
 857                 goto no_drive;
 858         }
 859
 860         /* First give it some more time, how much is "right" is hard to say :-( */
 861
 862         busy = ide_wait_not_busy(HWIF(drive), 100);     /* FIXME - uses mdelay which causes latency? */
 863         if (test_bit(IDESCSI_LOG_CMD, &scsi->log))
 864                 printk (KERN_WARNING "ide-scsi: drive did%s become ready\n", busy?" not":"");
 865
 866         spin_lock_irq(&ide_lock);
 867
 868         /* If there is no pc running we're done (our interrupt took care of it) */
 869         if (!scsi->pc) {
 870                 ret = SUCCESS;
 871                 goto ide_unlock;
 872         }
 873
 874         /* It's somewhere in flight. Does ide subsystem agree? */
 875         if (scsi->pc->scsi_cmd->serial_number == cmd->serial_number && !busy &&
 876             elv_queue_empty(drive->queue) && HWGROUP(drive)->rq != scsi->pc->rq) {
 877                 /*
 878                  * FIXME - not sure this condition can ever occur
 879                  */
 880                 printk (KERN_ERR "ide-scsi: cmd aborted!\n");
 881
 882                 if (blk_sense_request(scsi->pc->rq))
 883                         kfree(scsi->pc->buffer);
 884                 kfree(scsi->pc->rq);
 885                 kfree(scsi->pc);
 886                 scsi->pc = NULL;
 887
 888                 ret = SUCCESS;
 889         }
 890
 891 ide_unlock:
 892         spin_unlock_irq(&ide_lock);
 893 no_drive:
 894         if (test_bit(IDESCSI_LOG_CMD, &scsi->log))
 895                 printk (KERN_WARNING "ide-scsi: abort returns %s\n", ret == SUCCESS?"success":"failed");
 896
 897         return ret;
 898 }
 899
 900 static int idescsi_eh_reset (struct scsi_cmnd *cmd)
 901 {
 902         struct request *req;
 903         idescsi_scsi_t *scsi  = scsihost_to_idescsi(cmd->device->host);
 904         ide_drive_t    *drive = scsi->drive;
 905         int             ready = 0;
 906         int             ret   = SUCCESS;
 907
 908         /* In idescsi_eh_reset we forcefully remove the command from the ide subsystem and reset the device. */
 909
 910         if (test_bit(IDESCSI_LOG_CMD, &scsi->log))
 911                 printk (KERN_WARNING "ide-scsi: reset called for %lu\n", cmd->serial_number);
 912
 913         if (!drive) {
 914                 printk (KERN_WARNING "ide-scsi: Drive not set in idescsi_eh_reset\n");
 915                 WARN_ON(1);
 916                 return FAILED;
 917         }
 918
 919         spin_lock_irq(cmd->device->host->host_lock);
 920         spin_lock(&ide_lock);
 921
 922         if (!scsi->pc || (req = scsi->pc->rq) != HWGROUP(drive)->rq || !HWGROUP(drive)->handler) {
 923                 printk (KERN_WARNING "ide-scsi: No active request in idescsi_eh_reset\n");
 924                 spin_unlock(&ide_lock);
 925                 spin_unlock_irq(cmd->device->host->host_lock);
 926                 return FAILED;
 927         }
 928
 929         /* kill current request */
 930         blkdev_dequeue_request(req);
 931         end_that_request_last(req, 0);
 932         if (blk_sense_request(req))
 933                 kfree(scsi->pc->buffer);
 934         kfree(scsi->pc);
 935         scsi->pc = NULL;
 936         kfree(req);
 937
 938         /* now nuke the drive queue */
 939         while ((req = elv_next_request(drive->queue))) {
 940                 blkdev_dequeue_request(req);
 941                 end_that_request_last(req, 0);
 942         }
 943
 944         HWGROUP(drive)->rq = NULL;
 945         HWGROUP(drive)->handler = NULL;
 946         HWGROUP(drive)->busy = 1;               /* will set this to zero when ide reset finished */
 947         spin_unlock(&ide_lock);
 948
 949         ide_do_reset(drive);
 950
 951         /* ide_do_reset starts a polling handler which restarts itself every 50ms until the reset finishes */
 952
 953         do {
 954                 spin_unlock_irq(cmd->device->host->host_lock);
 955                 msleep(50);
 956                 spin_lock_irq(cmd->device->host->host_lock);
 957         } while ( HWGROUP(drive)->handler );
 958
 959         ready = drive_is_ready(drive);
 960         HWGROUP(drive)->busy--;
 961         if (!ready) {
 962                 printk (KERN_ERR "ide-scsi: reset failed!\n");
 963                 ret = FAILED;
 964         }
 965
 966         spin_unlock_irq(cmd->device->host->host_lock);
 967         return ret;
 968 }
 969
 970 static int idescsi_bios(struct scsi_device *sdev, struct block_device *bdev,
 971                 sector_t capacity, int *parm)
 972 {
 973         idescsi_scsi_t *idescsi = scsihost_to_idescsi(sdev->host);
 974         ide_drive_t *drive = idescsi->drive;
 975
 976         if (drive->bios_cyl && drive->bios_head && drive->bios_sect) {
 977                 parm[0] = drive->bios_head;
 978                 parm[1] = drive->bios_sect;
 979                 parm[2] = drive->bios_cyl;
 980         }
 981         return 0;
 982 }
 983
 984 static struct scsi_host_template idescsi_template = {
 985         .module                 = THIS_MODULE,
 986         .name                   = "idescsi",
 987         .info                   = idescsi_info,
 988         .slave_configure        = idescsi_slave_configure,
 989         .ioctl                  = idescsi_ioctl,
 990         .queuecommand           = idescsi_queue,
 991         .eh_abort_handler       = idescsi_eh_abort,
 992         .eh_host_reset_handler  = idescsi_eh_reset,
 993         .bios_param             = idescsi_bios,
 994         .can_queue              = 40,
 995         .this_id                = -1,
 996         .sg_tablesize           = 256,
 997         .cmd_per_lun            = 5,
 998         .max_sectors            = 128,
 999         .use_clustering         = DISABLE_CLUSTERING,
1000         .emulated               = 1,
1001         .proc_name              = "ide-scsi",
1002 };
1003
1004 static int ide_scsi_probe(ide_drive_t *drive)
1005 {
1006         idescsi_scsi_t *idescsi;
1007         struct Scsi_Host *host;
1008         struct gendisk *g;
1009         static int warned;
1010         int err = -ENOMEM;
1011
1012         if (!warned && drive->media == ide_cdrom) {
1013                 printk(KERN_WARNING "ide-scsi is deprecated for cd burning! Use ide-cd and give dev=/dev/hdX as device\n");
1014                 warned = 1;
1015         }
1016
1017         if (idescsi_nocd && drive->media == ide_cdrom)
1018                 return -ENODEV;
1019
1020         if (!strstr("ide-scsi", drive->driver_req) ||
1021             !drive->present ||
1022             drive->media == ide_disk ||
1023             !(host = scsi_host_alloc(&idescsi_template,sizeof(idescsi_scsi_t))))
1024                 return -ENODEV;
1025
1026         g = alloc_disk(1 << PARTN_BITS);
1027         if (!g)
1028                 goto out_host_put;
1029
1030         ide_init_disk(g, drive);
1031
1032         host->max_id = 1;
1033
1034 #if IDESCSI_DEBUG_LOG
1035         if (drive->id->last_lun)
1036                 printk(KERN_NOTICE "%s: id->last_lun=%u\n", drive->name, drive->id->last_lun);
1037 #endif
1038         if ((drive->id->last_lun & 0x7) != 7)
1039                 host->max_lun = (drive->id->last_lun & 0x7) + 1;
1040         else
1041                 host->max_lun = 1;
1042
1043         drive->driver_data = host;
1044         idescsi = scsihost_to_idescsi(host);
1045         idescsi->drive = drive;
1046         idescsi->driver = &idescsi_driver;
1047         idescsi->host = host;
1048         idescsi->disk = g;
1049         g->private_data = &idescsi->driver;
1050         ide_proc_register_driver(drive, &idescsi_driver);
1051         err = 0;
1052         idescsi_setup(drive, idescsi);
1053         g->fops = &idescsi_ops;
1054         ide_register_region(g);
1055         err = scsi_add_host(host, &drive->gendev);
1056         if (!err) {
1057                 scsi_scan_host(host);
1058                 return 0;
1059         }
1060         /* fall through on error */
1061         ide_unregister_region(g);
1062         ide_proc_unregister_driver(drive, &idescsi_driver);
1063
1064         put_disk(g);
1065 out_host_put:
1066         scsi_host_put(host);
1067         return err;
1068 }
1069
1070 static int __init init_idescsi_module(void)
1071 {
1072         return driver_register(&idescsi_driver.gen_driver);
1073 }
1074
1075 static void __exit exit_idescsi_module(void)
1076 {
1077         driver_unregister(&idescsi_driver.gen_driver);
1078 }
1079
1080 module_param(idescsi_nocd, int, 0600);
1081 MODULE_PARM_DESC(idescsi_nocd, "Disable handling of CD-ROMs so they may be driven by ide-cd");
1082 module_init(init_idescsi_module);
1083 module_exit(exit_idescsi_module);
1084 MODULE_LICENSE("GPL");