git.oblomov.eu Git - linux-2.6/blob - drivers/scsi/ide-scsi.c

   1 /*
   2  * Copyright (C) 1996-1999  Gadi Oxman <gadio@netvision.net.il>
   3  * Copyright (C) 2004-2005  Bartlomiej Zolnierkiewicz
   4  */
   5
   6 /*
   7  * Emulation of a SCSI host adapter for IDE ATAPI devices.
   8  *
   9  * With this driver, one can use the Linux SCSI drivers instead of the
  10  * native IDE ATAPI drivers.
  11  *
  12  * Ver 0.1   Dec  3 96   Initial version.
  13  * Ver 0.2   Jan 26 97   Fixed bug in cleanup_module() and added emulation
  14  *                        of MODE_SENSE_6/MODE_SELECT_6 for cdroms. Thanks
  15  *                        to Janos Farkas for pointing this out.
  16  *                       Avoid using bitfields in structures for m68k.
  17  *                       Added Scatter/Gather and DMA support.
  18  * Ver 0.4   Dec  7 97   Add support for ATAPI PD/CD drives.
  19  *                       Use variable timeout for each command.
  20  * Ver 0.5   Jan  2 98   Fix previous PD/CD support.
  21  *                       Allow disabling of SCSI-6 to SCSI-10 transformation.
  22  * Ver 0.6   Jan 27 98   Allow disabling of SCSI command translation layer
  23  *                        for access through /dev/sg.
  24  *                       Fix MODE_SENSE_6/MODE_SELECT_6/INQUIRY translation.
  25  * Ver 0.7   Dec 04 98   Ignore commands where lun != 0 to avoid multiple
  26  *                        detection of devices with CONFIG_SCSI_MULTI_LUN
  27  * Ver 0.8   Feb 05 99   Optical media need translation too. Reverse 0.7.
  28  * Ver 0.9   Jul 04 99   Fix a bug in SG_SET_TRANSFORM.
  29  * Ver 0.91  Jun 10 02   Fix "off by one" error in transforms
  30  * Ver 0.92  Dec 31 02   Implement new SCSI mid level API
  31  */
  32
  33 #define IDESCSI_VERSION "0.92"
  34
  35 #include <linux/module.h>
  36 #include <linux/types.h>
  37 #include <linux/string.h>
  38 #include <linux/kernel.h>
  39 #include <linux/mm.h>
  40 #include <linux/ioport.h>
  41 #include <linux/blkdev.h>
  42 #include <linux/errno.h>
  43 #include <linux/hdreg.h>
  44 #include <linux/slab.h>
  45 #include <linux/ide.h>
  46 #include <linux/scatterlist.h>
  47 #include <linux/delay.h>
  48 #include <linux/mutex.h>
  49 #include <linux/bitops.h>
  50
  51 #include <asm/io.h>
  52 #include <asm/uaccess.h>
  53
  54 #include <scsi/scsi.h>
  55 #include <scsi/scsi_cmnd.h>
  56 #include <scsi/scsi_device.h>
  57 #include <scsi/scsi_host.h>
  58 #include <scsi/scsi_tcq.h>
  59 #include <scsi/sg.h>
  60
  61 #define IDESCSI_DEBUG_LOG               0
  62
  63 typedef struct idescsi_pc_s {
  64         u8 c[12];                               /* Actual packet bytes */
  65         int request_transfer;                   /* Bytes to transfer */
  66         int actually_transferred;               /* Bytes actually transferred */
  67         int buffer_size;                        /* Size of our data buffer */
  68         struct request *rq;                     /* The corresponding request */
  69         u8 *buffer;                             /* Data buffer */
  70         u8 *current_position;                   /* Pointer into the above buffer */
  71         struct scatterlist *sg;                 /* Scatter gather table */
  72         unsigned int sg_cnt;                    /* Number of entries in sg */
  73         int b_count;                            /* Bytes transferred from current entry */
  74         struct scsi_cmnd *scsi_cmd;             /* SCSI command */
  75         void (*done)(struct scsi_cmnd *);       /* Scsi completion routine */
  76         unsigned long flags;                    /* Status/Action flags */
  77         unsigned long timeout;                  /* Command timeout */
  78 } idescsi_pc_t;
  79
  80 /*
  81  *      Packet command status bits.
  82  */
  83 #define PC_DMA_IN_PROGRESS              0       /* 1 while DMA in progress */
  84 #define PC_WRITING                      1       /* Data direction */
  85 #define PC_TIMEDOUT                     3       /* command timed out */
  86 #define PC_DMA_OK                       4       /* Use DMA */
  87
  88 /*
  89  *      SCSI command transformation layer
  90  */
  91 #define IDESCSI_SG_TRANSFORM            1       /* /dev/sg transformation */
  92
  93 /*
  94  *      Log flags
  95  */
  96 #define IDESCSI_LOG_CMD                 0       /* Log SCSI commands */
  97
  98 typedef struct ide_scsi_obj {
  99         ide_drive_t             *drive;
 100         ide_driver_t            *driver;
 101         struct gendisk          *disk;
 102         struct Scsi_Host        *host;
 103
 104         idescsi_pc_t *pc;                       /* Current packet command */
 105         unsigned long flags;                    /* Status/Action flags */
 106         unsigned long transform;                /* SCSI cmd translation layer */
 107         unsigned long log;                      /* log flags */
 108 } idescsi_scsi_t;
 109
 110 static DEFINE_MUTEX(idescsi_ref_mutex);
 111 static int idescsi_nocd;                        /* Set by module param to skip cd */
 112
 113 #define ide_scsi_g(disk) \
 114         container_of((disk)->private_data, struct ide_scsi_obj, driver)
 115
 116 static struct ide_scsi_obj *ide_scsi_get(struct gendisk *disk)
 117 {
 118         struct ide_scsi_obj *scsi = NULL;
 119
 120         mutex_lock(&idescsi_ref_mutex);
 121         scsi = ide_scsi_g(disk);
 122         if (scsi)
 123                 scsi_host_get(scsi->host);
 124         mutex_unlock(&idescsi_ref_mutex);
 125         return scsi;
 126 }
 127
 128 static void ide_scsi_put(struct ide_scsi_obj *scsi)
 129 {
 130         mutex_lock(&idescsi_ref_mutex);
 131         scsi_host_put(scsi->host);
 132         mutex_unlock(&idescsi_ref_mutex);
 133 }
 134
 135 static inline idescsi_scsi_t *scsihost_to_idescsi(struct Scsi_Host *host)
 136 {
 137         return (idescsi_scsi_t*) (&host[1]);
 138 }
 139
 140 static inline idescsi_scsi_t *drive_to_idescsi(ide_drive_t *ide_drive)
 141 {
 142         return scsihost_to_idescsi(ide_drive->driver_data);
 143 }
 144
 145 /*
 146  *      Per ATAPI device status bits.
 147  */
 148 #define IDESCSI_DRQ_INTERRUPT           0       /* DRQ interrupt device */
 149
 150 /*
 151  *      ide-scsi requests.
 152  */
 153 #define IDESCSI_PC_RQ                   90
 154
 155 static void idescsi_discard_data (ide_drive_t *drive, unsigned int bcount)
 156 {
 157         while (bcount--)
 158                 (void) HWIF(drive)->INB(IDE_DATA_REG);
 159 }
 160
 161 static void idescsi_output_zeros (ide_drive_t *drive, unsigned int bcount)
 162 {
 163         while (bcount--)
 164                 HWIF(drive)->OUTB(0, IDE_DATA_REG);
 165 }
 166
 167 /*
 168  *      PIO data transfer routines using the scatter gather table.
 169  */
 170 static void idescsi_input_buffers (ide_drive_t *drive, idescsi_pc_t *pc, unsigned int bcount)
 171 {
 172         int count;
 173         char *buf;
 174
 175         while (bcount) {
 176                 count = min(pc->sg->length - pc->b_count, bcount);
 177                 if (PageHighMem(sg_page(pc->sg))) {
 178                         unsigned long flags;
 179
 180                         local_irq_save(flags);
 181                         buf = kmap_atomic(sg_page(pc->sg), KM_IRQ0) +
 182                                         pc->sg->offset;
 183                         drive->hwif->atapi_input_bytes(drive,
 184                                                 buf + pc->b_count, count);
 185                         kunmap_atomic(buf - pc->sg->offset, KM_IRQ0);
 186                         local_irq_restore(flags);
 187                 } else {
 188                         buf = sg_virt(pc->sg);
 189                         drive->hwif->atapi_input_bytes(drive,
 190                                                 buf + pc->b_count, count);
 191                 }
 192                 bcount -= count; pc->b_count += count;
 193                 if (pc->b_count == pc->sg->length) {
 194                         if (!--pc->sg_cnt)
 195                                 break;
 196                         pc->sg = sg_next(pc->sg);
 197                         pc->b_count = 0;
 198                 }
 199         }
 200
 201         if (bcount) {
 202                 printk (KERN_ERR "ide-scsi: scatter gather table too small, discarding data\n");
 203                 idescsi_discard_data (drive, bcount);
 204         }
 205 }
 206
 207 static void idescsi_output_buffers (ide_drive_t *drive, idescsi_pc_t *pc, unsigned int bcount)
 208 {
 209         int count;
 210         char *buf;
 211
 212         while (bcount) {
 213                 count = min(pc->sg->length - pc->b_count, bcount);
 214                 if (PageHighMem(sg_page(pc->sg))) {
 215                         unsigned long flags;
 216
 217                         local_irq_save(flags);
 218                         buf = kmap_atomic(sg_page(pc->sg), KM_IRQ0) +
 219                                                 pc->sg->offset;
 220                         drive->hwif->atapi_output_bytes(drive,
 221                                                 buf + pc->b_count, count);
 222                         kunmap_atomic(buf - pc->sg->offset, KM_IRQ0);
 223                         local_irq_restore(flags);
 224                 } else {
 225                         buf = sg_virt(pc->sg);
 226                         drive->hwif->atapi_output_bytes(drive,
 227                                                 buf + pc->b_count, count);
 228                 }
 229                 bcount -= count; pc->b_count += count;
 230                 if (pc->b_count == pc->sg->length) {
 231                         if (!--pc->sg_cnt)
 232                                 break;
 233                         pc->sg = sg_next(pc->sg);
 234                         pc->b_count = 0;
 235                 }
 236         }
 237
 238         if (bcount) {
 239                 printk (KERN_ERR "ide-scsi: scatter gather table too small, padding with zeros\n");
 240                 idescsi_output_zeros (drive, bcount);
 241         }
 242 }
 243
 244 static void ide_scsi_hex_dump(u8 *data, int len)
 245 {
 246         print_hex_dump(KERN_CONT, "", DUMP_PREFIX_NONE, 16, 1, data, len, 0);
 247 }
 248
 249 static int idescsi_check_condition(ide_drive_t *drive, struct request *failed_command)
 250 {
 251         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
 252         idescsi_pc_t   *pc;
 253         struct request *rq;
 254         u8             *buf;
 255
 256         /* stuff a sense request in front of our current request */
 257         pc = kzalloc(sizeof(idescsi_pc_t), GFP_ATOMIC);
 258         rq = kmalloc(sizeof(struct request), GFP_ATOMIC);
 259         buf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_ATOMIC);
 260         if (!pc || !rq || !buf) {
 261                 kfree(buf);
 262                 kfree(rq);
 263                 kfree(pc);
 264                 return -ENOMEM;
 265         }
 266         ide_init_drive_cmd(rq);
 267         rq->special = (char *) pc;
 268         pc->rq = rq;
 269         pc->buffer = buf;
 270         pc->c[0] = REQUEST_SENSE;
 271         pc->c[4] = pc->request_transfer = pc->buffer_size = SCSI_SENSE_BUFFERSIZE;
 272         rq->cmd_type = REQ_TYPE_SENSE;
 273         pc->timeout = jiffies + WAIT_READY;
 274         /* NOTE! Save the failed packet command in "rq->buffer" */
 275         rq->buffer = (void *) failed_command->special;
 276         pc->scsi_cmd = ((idescsi_pc_t *) failed_command->special)->scsi_cmd;
 277         if (test_bit(IDESCSI_LOG_CMD, &scsi->log)) {
 278                 printk ("ide-scsi: %s: queue cmd = ", drive->name);
 279                 ide_scsi_hex_dump(pc->c, 6);
 280         }
 281         rq->rq_disk = scsi->disk;
 282         return ide_do_drive_cmd(drive, rq, ide_preempt);
 283 }
 284
 285 static int idescsi_end_request(ide_drive_t *, int, int);
 286
 287 static ide_startstop_t
 288 idescsi_atapi_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
 289 {
 290         if (ide_read_status(drive) & (BUSY_STAT | DRQ_STAT))
 291                 /* force an abort */
 292                 HWIF(drive)->OUTB(WIN_IDLEIMMEDIATE,IDE_COMMAND_REG);
 293
 294         rq->errors++;
 295
 296         idescsi_end_request(drive, 0, 0);
 297
 298         return ide_stopped;
 299 }
 300
 301 static ide_startstop_t
 302 idescsi_atapi_abort(ide_drive_t *drive, struct request *rq)
 303 {
 304 #if IDESCSI_DEBUG_LOG
 305         printk(KERN_WARNING "idescsi_atapi_abort called for %lu\n",
 306                         ((idescsi_pc_t *) rq->special)->scsi_cmd->serial_number);
 307 #endif
 308         rq->errors |= ERROR_MAX;
 309
 310         idescsi_end_request(drive, 0, 0);
 311
 312         return ide_stopped;
 313 }
 314
 315 static int idescsi_end_request (ide_drive_t *drive, int uptodate, int nrsecs)
 316 {
 317         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
 318         struct request *rq = HWGROUP(drive)->rq;
 319         idescsi_pc_t *pc = (idescsi_pc_t *) rq->special;
 320         int log = test_bit(IDESCSI_LOG_CMD, &scsi->log);
 321         struct Scsi_Host *host;
 322         int errors = rq->errors;
 323         unsigned long flags;
 324
 325         if (!blk_special_request(rq) && !blk_sense_request(rq)) {
 326                 ide_end_request(drive, uptodate, nrsecs);
 327                 return 0;
 328         }
 329         ide_end_drive_cmd (drive, 0, 0);
 330         if (blk_sense_request(rq)) {
 331                 idescsi_pc_t *opc = (idescsi_pc_t *) rq->buffer;
 332                 if (log) {
 333                         printk ("ide-scsi: %s: wrap up check %lu, rst = ", drive->name, opc->scsi_cmd->serial_number);
 334                         ide_scsi_hex_dump(pc->buffer, 16);
 335                 }
 336                 memcpy((void *) opc->scsi_cmd->sense_buffer, pc->buffer, SCSI_SENSE_BUFFERSIZE);
 337                 kfree(pc->buffer);
 338                 kfree(pc);
 339                 kfree(rq);
 340                 pc = opc;
 341                 rq = pc->rq;
 342                 pc->scsi_cmd->result = (CHECK_CONDITION << 1) |
 343                                         ((test_bit(PC_TIMEDOUT, &pc->flags)?DID_TIME_OUT:DID_OK) << 16);
 344         } else if (test_bit(PC_TIMEDOUT, &pc->flags)) {
 345                 if (log)
 346                         printk (KERN_WARNING "ide-scsi: %s: timed out for %lu\n",
 347                                         drive->name, pc->scsi_cmd->serial_number);
 348                 pc->scsi_cmd->result = DID_TIME_OUT << 16;
 349         } else if (errors >= ERROR_MAX) {
 350                 pc->scsi_cmd->result = DID_ERROR << 16;
 351                 if (log)
 352                         printk ("ide-scsi: %s: I/O error for %lu\n", drive->name, pc->scsi_cmd->serial_number);
 353         } else if (errors) {
 354                 if (log)
 355                         printk ("ide-scsi: %s: check condition for %lu\n", drive->name, pc->scsi_cmd->serial_number);
 356                 if (!idescsi_check_condition(drive, rq))
 357                         /* we started a request sense, so we'll be back, exit for now */
 358                         return 0;
 359                 pc->scsi_cmd->result = (CHECK_CONDITION << 1) | (DID_OK << 16);
 360         } else {
 361                 pc->scsi_cmd->result = DID_OK << 16;
 362         }
 363         host = pc->scsi_cmd->device->host;
 364         spin_lock_irqsave(host->host_lock, flags);
 365         pc->done(pc->scsi_cmd);
 366         spin_unlock_irqrestore(host->host_lock, flags);
 367         kfree(pc);
 368         kfree(rq);
 369         scsi->pc = NULL;
 370         return 0;
 371 }
 372
 373 static inline unsigned long get_timeout(idescsi_pc_t *pc)
 374 {
 375         return max_t(unsigned long, WAIT_CMD, pc->timeout - jiffies);
 376 }
 377
 378 static int idescsi_expiry(ide_drive_t *drive)
 379 {
 380         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
 381         idescsi_pc_t   *pc   = scsi->pc;
 382
 383 #if IDESCSI_DEBUG_LOG
 384         printk(KERN_WARNING "idescsi_expiry called for %lu at %lu\n", pc->scsi_cmd->serial_number, jiffies);
 385 #endif
 386         set_bit(PC_TIMEDOUT, &pc->flags);
 387
 388         return 0;                                       /* we do not want the ide subsystem to retry */
 389 }
 390
 391 /*
 392  *      Our interrupt handler.
 393  */
 394 static ide_startstop_t idescsi_pc_intr (ide_drive_t *drive)
 395 {
 396         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
 397         ide_hwif_t *hwif = drive->hwif;
 398         idescsi_pc_t *pc = scsi->pc;
 399         struct request *rq = pc->rq;
 400         unsigned int temp;
 401         u16 bcount;
 402         u8 stat, ireason;
 403
 404 #if IDESCSI_DEBUG_LOG
 405         printk (KERN_INFO "ide-scsi: Reached idescsi_pc_intr interrupt handler\n");
 406 #endif /* IDESCSI_DEBUG_LOG */
 407
 408         if (test_bit(PC_TIMEDOUT, &pc->flags)){
 409 #if IDESCSI_DEBUG_LOG
 410                 printk(KERN_WARNING "idescsi_pc_intr: got timed out packet  %lu at %lu\n",
 411                                 pc->scsi_cmd->serial_number, jiffies);
 412 #endif
 413                 /* end this request now - scsi should retry it*/
 414                 idescsi_end_request (drive, 1, 0);
 415                 return ide_stopped;
 416         }
 417         if (test_and_clear_bit (PC_DMA_IN_PROGRESS, &pc->flags)) {
 418 #if IDESCSI_DEBUG_LOG
 419                 printk ("ide-scsi: %s: DMA complete\n", drive->name);
 420 #endif /* IDESCSI_DEBUG_LOG */
 421                 pc->actually_transferred=pc->request_transfer;
 422                 (void) HWIF(drive)->ide_dma_end(drive);
 423         }
 424
 425         /* Clear the interrupt */
 426         stat = ide_read_status(drive);
 427
 428         if ((stat & DRQ_STAT) == 0) {
 429                 /* No more interrupts */
 430                 if (test_bit(IDESCSI_LOG_CMD, &scsi->log))
 431                         printk (KERN_INFO "Packet command completed, %d bytes transferred\n", pc->actually_transferred);
 432                 local_irq_enable_in_hardirq();
 433                 if (stat & ERR_STAT)
 434                         rq->errors++;
 435                 idescsi_end_request (drive, 1, 0);
 436                 return ide_stopped;
 437         }
 438         bcount = (hwif->INB(IDE_BCOUNTH_REG) << 8) |
 439                   hwif->INB(IDE_BCOUNTL_REG);
 440         ireason = hwif->INB(IDE_IREASON_REG);
 441
 442         if (ireason & CD) {
 443                 printk(KERN_ERR "ide-scsi: CoD != 0 in idescsi_pc_intr\n");
 444                 return ide_do_reset (drive);
 445         }
 446         if (ireason & IO) {
 447                 temp = pc->actually_transferred + bcount;
 448                 if (temp > pc->request_transfer) {
 449                         if (temp > pc->buffer_size) {
 450                                 printk(KERN_ERR "ide-scsi: The scsi wants to "
 451                                         "send us more data than expected "
 452                                         "- discarding data\n");
 453                                 temp = pc->buffer_size - pc->actually_transferred;
 454                                 if (temp) {
 455                                         clear_bit(PC_WRITING, &pc->flags);
 456                                         if (pc->sg)
 457                                                 idescsi_input_buffers(drive, pc, temp);
 458                                         else
 459                                                 drive->hwif->atapi_input_bytes(drive, pc->current_position, temp);
 460                                         printk(KERN_ERR "ide-scsi: transferred"
 461                                                         " %d of %d bytes\n",
 462                                                         temp, bcount);
 463                                 }
 464                                 pc->actually_transferred += temp;
 465                                 pc->current_position += temp;
 466                                 idescsi_discard_data(drive, bcount - temp);
 467                                 ide_set_handler(drive, &idescsi_pc_intr, get_timeout(pc), idescsi_expiry);
 468                                 return ide_started;
 469                         }
 470 #if IDESCSI_DEBUG_LOG
 471                         printk (KERN_NOTICE "ide-scsi: The scsi wants to send us more data than expected - allowing transfer\n");
 472 #endif /* IDESCSI_DEBUG_LOG */
 473                 }
 474         }
 475         if (ireason & IO) {
 476                 clear_bit(PC_WRITING, &pc->flags);
 477                 if (pc->sg)
 478                         idescsi_input_buffers(drive, pc, bcount);
 479                 else
 480                         hwif->atapi_input_bytes(drive, pc->current_position,
 481                                                 bcount);
 482         } else {
 483                 set_bit(PC_WRITING, &pc->flags);
 484                 if (pc->sg)
 485                         idescsi_output_buffers(drive, pc, bcount);
 486                 else
 487                         hwif->atapi_output_bytes(drive, pc->current_position,
 488                                                  bcount);
 489         }
 490         /* Update the current position */
 491         pc->actually_transferred += bcount;
 492         pc->current_position += bcount;
 493
 494         /* And set the interrupt handler again */
 495         ide_set_handler(drive, &idescsi_pc_intr, get_timeout(pc), idescsi_expiry);
 496         return ide_started;
 497 }
 498
 499 static ide_startstop_t idescsi_transfer_pc(ide_drive_t *drive)
 500 {
 501         ide_hwif_t *hwif = drive->hwif;
 502         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
 503         idescsi_pc_t *pc = scsi->pc;
 504         ide_startstop_t startstop;
 505         u8 ireason;
 506
 507         if (ide_wait_stat(&startstop,drive,DRQ_STAT,BUSY_STAT,WAIT_READY)) {
 508                 printk(KERN_ERR "ide-scsi: Strange, packet command "
 509                         "initiated yet DRQ isn't asserted\n");
 510                 return startstop;
 511         }
 512         ireason = hwif->INB(IDE_IREASON_REG);
 513         if ((ireason & CD) == 0 || (ireason & IO)) {
 514                 printk(KERN_ERR "ide-scsi: (IO,CoD) != (0,1) while "
 515                                 "issuing a packet command\n");
 516                 return ide_do_reset (drive);
 517         }
 518         BUG_ON(HWGROUP(drive)->handler != NULL);
 519         /* Set the interrupt routine */
 520         ide_set_handler(drive, &idescsi_pc_intr, get_timeout(pc), idescsi_expiry);
 521         /* Send the actual packet */
 522         drive->hwif->atapi_output_bytes(drive, scsi->pc->c, 12);
 523         if (test_bit (PC_DMA_OK, &pc->flags)) {
 524                 set_bit (PC_DMA_IN_PROGRESS, &pc->flags);
 525                 hwif->dma_start(drive);
 526         }
 527         return ide_started;
 528 }
 529
 530 static inline int idescsi_set_direction(idescsi_pc_t *pc)
 531 {
 532         switch (pc->c[0]) {
 533                 case READ_6: case READ_10: case READ_12:
 534                         clear_bit(PC_WRITING, &pc->flags);
 535                         return 0;
 536                 case WRITE_6: case WRITE_10: case WRITE_12:
 537                         set_bit(PC_WRITING, &pc->flags);
 538                         return 0;
 539                 default:
 540                         return 1;
 541         }
 542 }
 543
 544 static int idescsi_map_sg(ide_drive_t *drive, idescsi_pc_t *pc)
 545 {
 546         ide_hwif_t *hwif = drive->hwif;
 547         struct scatterlist *sg, *scsi_sg;
 548         int segments;
 549
 550         if (!pc->request_transfer || pc->request_transfer % 1024)
 551                 return 1;
 552
 553         if (idescsi_set_direction(pc))
 554                 return 1;
 555
 556         sg = hwif->sg_table;
 557         scsi_sg = scsi_sglist(pc->scsi_cmd);
 558         segments = scsi_sg_count(pc->scsi_cmd);
 559
 560         if (segments > hwif->sg_max_nents)
 561                 return 1;
 562
 563         hwif->sg_nents = segments;
 564         memcpy(sg, scsi_sg, sizeof(*sg) * segments);
 565
 566         return 0;
 567 }
 568
 569 /*
 570  *      Issue a packet command
 571  */
 572 static ide_startstop_t idescsi_issue_pc (ide_drive_t *drive, idescsi_pc_t *pc)
 573 {
 574         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
 575         ide_hwif_t *hwif = drive->hwif;
 576         u16 bcount;
 577         u8 dma = 0;
 578
 579         scsi->pc=pc;                                                    /* Set the current packet command */
 580         pc->actually_transferred=0;                                     /* We haven't transferred any data yet */
 581         pc->current_position=pc->buffer;
 582         /* Request to transfer the entire buffer at once */
 583         bcount = min(pc->request_transfer, 63 * 1024);
 584
 585         if (drive->using_dma && !idescsi_map_sg(drive, pc)) {
 586                 hwif->sg_mapped = 1;
 587                 dma = !hwif->dma_setup(drive);
 588                 hwif->sg_mapped = 0;
 589         }
 590
 591         ide_pktcmd_tf_load(drive, IDE_TFLAG_NO_SELECT_MASK, bcount, dma);
 592
 593         if (dma)
 594                 set_bit(PC_DMA_OK, &pc->flags);
 595
 596         if (test_bit(IDESCSI_DRQ_INTERRUPT, &scsi->flags)) {
 597                 ide_execute_command(drive, WIN_PACKETCMD, &idescsi_transfer_pc,
 598                                     get_timeout(pc), idescsi_expiry);
 599                 return ide_started;
 600         } else {
 601                 /* Issue the packet command */
 602                 HWIF(drive)->OUTB(WIN_PACKETCMD, IDE_COMMAND_REG);
 603                 return idescsi_transfer_pc(drive);
 604         }
 605 }
 606
 607 /*
 608  *      idescsi_do_request is our request handling function.
 609  */
 610 static ide_startstop_t idescsi_do_request (ide_drive_t *drive, struct request *rq, sector_t block)
 611 {
 612 #if IDESCSI_DEBUG_LOG
 613         printk (KERN_INFO "dev: %s, cmd: %x, errors: %d\n", rq->rq_disk->disk_name,rq->cmd[0],rq->errors);
 614         printk (KERN_INFO "sector: %ld, nr_sectors: %ld, current_nr_sectors: %d\n",rq->sector,rq->nr_sectors,rq->current_nr_sectors);
 615 #endif /* IDESCSI_DEBUG_LOG */
 616
 617         if (blk_sense_request(rq) || blk_special_request(rq)) {
 618                 return idescsi_issue_pc (drive, (idescsi_pc_t *) rq->special);
 619         }
 620         blk_dump_rq_flags(rq, "ide-scsi: unsup command");
 621         idescsi_end_request (drive, 0, 0);
 622         return ide_stopped;
 623 }
 624
 625 #ifdef CONFIG_IDE_PROC_FS
 626 static void idescsi_add_settings(ide_drive_t *drive)
 627 {
 628         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
 629
 630 /*
 631  *                      drive   setting name    read/write      data type       min     max     mul_factor      div_factor      data pointer            set function
 632  */
 633         ide_add_setting(drive,  "bios_cyl",     SETTING_RW,     TYPE_INT,       0,      1023,   1,              1,              &drive->bios_cyl,       NULL);
 634         ide_add_setting(drive,  "bios_head",    SETTING_RW,     TYPE_BYTE,      0,      255,    1,              1,              &drive->bios_head,      NULL);
 635         ide_add_setting(drive,  "bios_sect",    SETTING_RW,     TYPE_BYTE,      0,      63,     1,              1,              &drive->bios_sect,      NULL);
 636         ide_add_setting(drive,  "transform",    SETTING_RW,     TYPE_INT,       0,      3,      1,              1,              &scsi->transform,       NULL);
 637         ide_add_setting(drive,  "log",          SETTING_RW,     TYPE_INT,       0,      1,      1,              1,              &scsi->log,             NULL);
 638 }
 639 #else
 640 static inline void idescsi_add_settings(ide_drive_t *drive) { ; }
 641 #endif
 642
 643 /*
 644  *      Driver initialization.
 645  */
 646 static void idescsi_setup (ide_drive_t *drive, idescsi_scsi_t *scsi)
 647 {
 648         if (drive->id && (drive->id->config & 0x0060) == 0x20)
 649                 set_bit (IDESCSI_DRQ_INTERRUPT, &scsi->flags);
 650         clear_bit(IDESCSI_SG_TRANSFORM, &scsi->transform);
 651 #if IDESCSI_DEBUG_LOG
 652         set_bit(IDESCSI_LOG_CMD, &scsi->log);
 653 #endif /* IDESCSI_DEBUG_LOG */
 654         idescsi_add_settings(drive);
 655 }
 656
 657 static void ide_scsi_remove(ide_drive_t *drive)
 658 {
 659         struct Scsi_Host *scsihost = drive->driver_data;
 660         struct ide_scsi_obj *scsi = scsihost_to_idescsi(scsihost);
 661         struct gendisk *g = scsi->disk;
 662
 663         scsi_remove_host(scsihost);
 664         ide_proc_unregister_driver(drive, scsi->driver);
 665
 666         ide_unregister_region(g);
 667
 668         drive->driver_data = NULL;
 669         g->private_data = NULL;
 670         put_disk(g);
 671
 672         ide_scsi_put(scsi);
 673 }
 674
 675 static int ide_scsi_probe(ide_drive_t *);
 676
 677 #ifdef CONFIG_IDE_PROC_FS
 678 static ide_proc_entry_t idescsi_proc[] = {
 679         { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL },
 680         { NULL, 0, NULL, NULL }
 681 };
 682 #endif
 683
 684 static ide_driver_t idescsi_driver = {
 685         .gen_driver = {
 686                 .owner          = THIS_MODULE,
 687                 .name           = "ide-scsi",
 688                 .bus            = &ide_bus_type,
 689         },
 690         .probe                  = ide_scsi_probe,
 691         .remove                 = ide_scsi_remove,
 692         .version                = IDESCSI_VERSION,
 693         .media                  = ide_scsi,
 694         .supports_dsc_overlap   = 0,
 695         .do_request             = idescsi_do_request,
 696         .end_request            = idescsi_end_request,
 697         .error                  = idescsi_atapi_error,
 698         .abort                  = idescsi_atapi_abort,
 699 #ifdef CONFIG_IDE_PROC_FS
 700         .proc                   = idescsi_proc,
 701 #endif
 702 };
 703
 704 static int idescsi_ide_open(struct inode *inode, struct file *filp)
 705 {
 706         struct gendisk *disk = inode->i_bdev->bd_disk;
 707         struct ide_scsi_obj *scsi;
 708
 709         if (!(scsi = ide_scsi_get(disk)))
 710                 return -ENXIO;
 711
 712         return 0;
 713 }
 714
 715 static int idescsi_ide_release(struct inode *inode, struct file *filp)
 716 {
 717         struct gendisk *disk = inode->i_bdev->bd_disk;
 718         struct ide_scsi_obj *scsi = ide_scsi_g(disk);
 719
 720         ide_scsi_put(scsi);
 721
 722         return 0;
 723 }
 724
 725 static int idescsi_ide_ioctl(struct inode *inode, struct file *file,
 726                         unsigned int cmd, unsigned long arg)
 727 {
 728         struct block_device *bdev = inode->i_bdev;
 729         struct ide_scsi_obj *scsi = ide_scsi_g(bdev->bd_disk);
 730         return generic_ide_ioctl(scsi->drive, file, bdev, cmd, arg);
 731 }
 732
 733 static struct block_device_operations idescsi_ops = {
 734         .owner          = THIS_MODULE,
 735         .open           = idescsi_ide_open,
 736         .release        = idescsi_ide_release,
 737         .ioctl          = idescsi_ide_ioctl,
 738 };
 739
 740 static int idescsi_slave_configure(struct scsi_device * sdp)
 741 {
 742         /* Configure detected device */
 743         sdp->use_10_for_rw = 1;
 744         sdp->use_10_for_ms = 1;
 745         scsi_adjust_queue_depth(sdp, MSG_SIMPLE_TAG, sdp->host->cmd_per_lun);
 746         return 0;
 747 }
 748
 749 static const char *idescsi_info (struct Scsi_Host *host)
 750 {
 751         return "SCSI host adapter emulation for IDE ATAPI devices";
 752 }
 753
 754 static int idescsi_ioctl (struct scsi_device *dev, int cmd, void __user *arg)
 755 {
 756         idescsi_scsi_t *scsi = scsihost_to_idescsi(dev->host);
 757
 758         if (cmd == SG_SET_TRANSFORM) {
 759                 if (arg)
 760                         set_bit(IDESCSI_SG_TRANSFORM, &scsi->transform);
 761                 else
 762                         clear_bit(IDESCSI_SG_TRANSFORM, &scsi->transform);
 763                 return 0;
 764         } else if (cmd == SG_GET_TRANSFORM)
 765                 return put_user(test_bit(IDESCSI_SG_TRANSFORM, &scsi->transform), (int __user *) arg);
 766         return -EINVAL;
 767 }
 768
 769 static int idescsi_queue (struct scsi_cmnd *cmd,
 770                 void (*done)(struct scsi_cmnd *))
 771 {
 772         struct Scsi_Host *host = cmd->device->host;
 773         idescsi_scsi_t *scsi = scsihost_to_idescsi(host);
 774         ide_drive_t *drive = scsi->drive;
 775         struct request *rq = NULL;
 776         idescsi_pc_t *pc = NULL;
 777
 778         if (!drive) {
 779                 scmd_printk (KERN_ERR, cmd, "drive not present\n");
 780                 goto abort;
 781         }
 782         scsi = drive_to_idescsi(drive);
 783         pc = kmalloc (sizeof (idescsi_pc_t), GFP_ATOMIC);
 784         rq = kmalloc (sizeof (struct request), GFP_ATOMIC);
 785         if (rq == NULL || pc == NULL) {
 786                 printk (KERN_ERR "ide-scsi: %s: out of memory\n", drive->name);
 787                 goto abort;
 788         }
 789
 790         memset (pc->c, 0, 12);
 791         pc->flags = 0;
 792         pc->rq = rq;
 793         memcpy (pc->c, cmd->cmnd, cmd->cmd_len);
 794         pc->buffer = NULL;
 795         pc->sg = scsi_sglist(cmd);
 796         pc->sg_cnt = scsi_sg_count(cmd);
 797         pc->b_count = 0;
 798         pc->request_transfer = pc->buffer_size = scsi_bufflen(cmd);
 799         pc->scsi_cmd = cmd;
 800         pc->done = done;
 801         pc->timeout = jiffies + cmd->timeout_per_command;
 802
 803         if (test_bit(IDESCSI_LOG_CMD, &scsi->log)) {
 804                 printk ("ide-scsi: %s: que %lu, cmd = ", drive->name, cmd->serial_number);
 805                 ide_scsi_hex_dump(cmd->cmnd, cmd->cmd_len);
 806                 if (memcmp(pc->c, cmd->cmnd, cmd->cmd_len)) {
 807                         printk ("ide-scsi: %s: que %lu, tsl = ", drive->name, cmd->serial_number);
 808                         ide_scsi_hex_dump(pc->c, 12);
 809                 }
 810         }
 811
 812         ide_init_drive_cmd (rq);
 813         rq->special = (char *) pc;
 814         rq->cmd_type = REQ_TYPE_SPECIAL;
 815         spin_unlock_irq(host->host_lock);
 816         rq->rq_disk = scsi->disk;
 817         (void) ide_do_drive_cmd (drive, rq, ide_end);
 818         spin_lock_irq(host->host_lock);
 819         return 0;
 820 abort:
 821         kfree (pc);
 822         kfree (rq);
 823         cmd->result = DID_ERROR << 16;
 824         done(cmd);
 825         return 0;
 826 }
 827
 828 static int idescsi_eh_abort (struct scsi_cmnd *cmd)
 829 {
 830         idescsi_scsi_t *scsi  = scsihost_to_idescsi(cmd->device->host);
 831         ide_drive_t    *drive = scsi->drive;
 832         int             busy;
 833         int             ret   = FAILED;
 834
 835         /* In idescsi_eh_abort we try to gently pry our command from the ide subsystem */
 836
 837         if (test_bit(IDESCSI_LOG_CMD, &scsi->log))
 838                 printk (KERN_WARNING "ide-scsi: abort called for %lu\n", cmd->serial_number);
 839
 840         if (!drive) {
 841                 printk (KERN_WARNING "ide-scsi: Drive not set in idescsi_eh_abort\n");
 842                 WARN_ON(1);
 843                 goto no_drive;
 844         }
 845
 846         /* First give it some more time, how much is "right" is hard to say :-( */
 847
 848         busy = ide_wait_not_busy(HWIF(drive), 100);     /* FIXME - uses mdelay which causes latency? */
 849         if (test_bit(IDESCSI_LOG_CMD, &scsi->log))
 850                 printk (KERN_WARNING "ide-scsi: drive did%s become ready\n", busy?" not":"");
 851
 852         spin_lock_irq(&ide_lock);
 853
 854         /* If there is no pc running we're done (our interrupt took care of it) */
 855         if (!scsi->pc) {
 856                 ret = SUCCESS;
 857                 goto ide_unlock;
 858         }
 859
 860         /* It's somewhere in flight. Does ide subsystem agree? */
 861         if (scsi->pc->scsi_cmd->serial_number == cmd->serial_number && !busy &&
 862             elv_queue_empty(drive->queue) && HWGROUP(drive)->rq != scsi->pc->rq) {
 863                 /*
 864                  * FIXME - not sure this condition can ever occur
 865                  */
 866                 printk (KERN_ERR "ide-scsi: cmd aborted!\n");
 867
 868                 if (blk_sense_request(scsi->pc->rq))
 869                         kfree(scsi->pc->buffer);
 870                 kfree(scsi->pc->rq);
 871                 kfree(scsi->pc);
 872                 scsi->pc = NULL;
 873
 874                 ret = SUCCESS;
 875         }
 876
 877 ide_unlock:
 878         spin_unlock_irq(&ide_lock);
 879 no_drive:
 880         if (test_bit(IDESCSI_LOG_CMD, &scsi->log))
 881                 printk (KERN_WARNING "ide-scsi: abort returns %s\n", ret == SUCCESS?"success":"failed");
 882
 883         return ret;
 884 }
 885
 886 static int idescsi_eh_reset (struct scsi_cmnd *cmd)
 887 {
 888         struct request *req;
 889         idescsi_scsi_t *scsi  = scsihost_to_idescsi(cmd->device->host);
 890         ide_drive_t    *drive = scsi->drive;
 891         int             ready = 0;
 892         int             ret   = SUCCESS;
 893
 894         /* In idescsi_eh_reset we forcefully remove the command from the ide subsystem and reset the device. */
 895
 896         if (test_bit(IDESCSI_LOG_CMD, &scsi->log))
 897                 printk (KERN_WARNING "ide-scsi: reset called for %lu\n", cmd->serial_number);
 898
 899         if (!drive) {
 900                 printk (KERN_WARNING "ide-scsi: Drive not set in idescsi_eh_reset\n");
 901                 WARN_ON(1);
 902                 return FAILED;
 903         }
 904
 905         spin_lock_irq(cmd->device->host->host_lock);
 906         spin_lock(&ide_lock);
 907
 908         if (!scsi->pc || (req = scsi->pc->rq) != HWGROUP(drive)->rq || !HWGROUP(drive)->handler) {
 909                 printk (KERN_WARNING "ide-scsi: No active request in idescsi_eh_reset\n");
 910                 spin_unlock(&ide_lock);
 911                 spin_unlock_irq(cmd->device->host->host_lock);
 912                 return FAILED;
 913         }
 914
 915         /* kill current request */
 916         if (__blk_end_request(req, -EIO, 0))
 917                 BUG();
 918         if (blk_sense_request(req))
 919                 kfree(scsi->pc->buffer);
 920         kfree(scsi->pc);
 921         scsi->pc = NULL;
 922         kfree(req);
 923
 924         /* now nuke the drive queue */
 925         while ((req = elv_next_request(drive->queue))) {
 926                 if (__blk_end_request(req, -EIO, 0))
 927                         BUG();
 928         }
 929
 930         HWGROUP(drive)->rq = NULL;
 931         HWGROUP(drive)->handler = NULL;
 932         HWGROUP(drive)->busy = 1;               /* will set this to zero when ide reset finished */
 933         spin_unlock(&ide_lock);
 934
 935         ide_do_reset(drive);
 936
 937         /* ide_do_reset starts a polling handler which restarts itself every 50ms until the reset finishes */
 938
 939         do {
 940                 spin_unlock_irq(cmd->device->host->host_lock);
 941                 msleep(50);
 942                 spin_lock_irq(cmd->device->host->host_lock);
 943         } while ( HWGROUP(drive)->handler );
 944
 945         ready = drive_is_ready(drive);
 946         HWGROUP(drive)->busy--;
 947         if (!ready) {
 948                 printk (KERN_ERR "ide-scsi: reset failed!\n");
 949                 ret = FAILED;
 950         }
 951
 952         spin_unlock_irq(cmd->device->host->host_lock);
 953         return ret;
 954 }
 955
 956 static int idescsi_bios(struct scsi_device *sdev, struct block_device *bdev,
 957                 sector_t capacity, int *parm)
 958 {
 959         idescsi_scsi_t *idescsi = scsihost_to_idescsi(sdev->host);
 960         ide_drive_t *drive = idescsi->drive;
 961
 962         if (drive->bios_cyl && drive->bios_head && drive->bios_sect) {
 963                 parm[0] = drive->bios_head;
 964                 parm[1] = drive->bios_sect;
 965                 parm[2] = drive->bios_cyl;
 966         }
 967         return 0;
 968 }
 969
 970 static struct scsi_host_template idescsi_template = {
 971         .module                 = THIS_MODULE,
 972         .name                   = "idescsi",
 973         .info                   = idescsi_info,
 974         .slave_configure        = idescsi_slave_configure,
 975         .ioctl                  = idescsi_ioctl,
 976         .queuecommand           = idescsi_queue,
 977         .eh_abort_handler       = idescsi_eh_abort,
 978         .eh_host_reset_handler  = idescsi_eh_reset,
 979         .bios_param             = idescsi_bios,
 980         .can_queue              = 40,
 981         .this_id                = -1,
 982         .sg_tablesize           = 256,
 983         .cmd_per_lun            = 5,
 984         .max_sectors            = 128,
 985         .use_clustering         = DISABLE_CLUSTERING,
 986         .emulated               = 1,
 987         .proc_name              = "ide-scsi",
 988 };
 989
 990 static int ide_scsi_probe(ide_drive_t *drive)
 991 {
 992         idescsi_scsi_t *idescsi;
 993         struct Scsi_Host *host;
 994         struct gendisk *g;
 995         static int warned;
 996         int err = -ENOMEM;
 997
 998         if (!warned && drive->media == ide_cdrom) {
 999                 printk(KERN_WARNING "ide-scsi is deprecated for cd burning! Use ide-cd and give dev=/dev/hdX as device\n");
1000                 warned = 1;
1001         }
1002
1003         if (idescsi_nocd && drive->media == ide_cdrom)
1004                 return -ENODEV;
1005
1006         if (!strstr("ide-scsi", drive->driver_req) ||
1007             !drive->present ||
1008             drive->media == ide_disk ||
1009             !(host = scsi_host_alloc(&idescsi_template,sizeof(idescsi_scsi_t))))
1010                 return -ENODEV;
1011
1012         g = alloc_disk(1 << PARTN_BITS);
1013         if (!g)
1014                 goto out_host_put;
1015
1016         ide_init_disk(g, drive);
1017
1018         host->max_id = 1;
1019
1020 #if IDESCSI_DEBUG_LOG
1021         if (drive->id->last_lun)
1022                 printk(KERN_NOTICE "%s: id->last_lun=%u\n", drive->name, drive->id->last_lun);
1023 #endif
1024         if ((drive->id->last_lun & 0x7) != 7)
1025                 host->max_lun = (drive->id->last_lun & 0x7) + 1;
1026         else
1027                 host->max_lun = 1;
1028
1029         drive->driver_data = host;
1030         idescsi = scsihost_to_idescsi(host);
1031         idescsi->drive = drive;
1032         idescsi->driver = &idescsi_driver;
1033         idescsi->host = host;
1034         idescsi->disk = g;
1035         g->private_data = &idescsi->driver;
1036         ide_proc_register_driver(drive, &idescsi_driver);
1037         err = 0;
1038         idescsi_setup(drive, idescsi);
1039         g->fops = &idescsi_ops;
1040         ide_register_region(g);
1041         err = scsi_add_host(host, &drive->gendev);
1042         if (!err) {
1043                 scsi_scan_host(host);
1044                 return 0;
1045         }
1046         /* fall through on error */
1047         ide_unregister_region(g);
1048         ide_proc_unregister_driver(drive, &idescsi_driver);
1049
1050         put_disk(g);
1051 out_host_put:
1052         scsi_host_put(host);
1053         return err;
1054 }
1055
1056 static int __init init_idescsi_module(void)
1057 {
1058         return driver_register(&idescsi_driver.gen_driver);
1059 }
1060
1061 static void __exit exit_idescsi_module(void)
1062 {
1063         driver_unregister(&idescsi_driver.gen_driver);
1064 }
1065
1066 module_param(idescsi_nocd, int, 0600);
1067 MODULE_PARM_DESC(idescsi_nocd, "Disable handling of CD-ROMs so they may be driven by ide-cd");
1068 module_init(init_idescsi_module);
1069 module_exit(exit_idescsi_module);
1070 MODULE_LICENSE("GPL");