git.oblomov.eu Git - linux-2.6/blob - 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 ide_scsi_hex_dump(u8 *data, int len)
 246 {
 247         print_hex_dump(KERN_CONT, "", DUMP_PREFIX_NONE, 16, 1, data, len, 0);
 248 }
 249
 250 static int idescsi_check_condition(ide_drive_t *drive, struct request *failed_command)
 251 {
 252         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
 253         idescsi_pc_t   *pc;
 254         struct request *rq;
 255         u8             *buf;
 256
 257         /* stuff a sense request in front of our current request */
 258         pc = kzalloc(sizeof(idescsi_pc_t), GFP_ATOMIC);
 259         rq = kmalloc(sizeof(struct request), GFP_ATOMIC);
 260         buf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_ATOMIC);
 261         if (!pc || !rq || !buf) {
 262                 kfree(buf);
 263                 kfree(rq);
 264                 kfree(pc);
 265                 return -ENOMEM;
 266         }
 267         ide_init_drive_cmd(rq);
 268         rq->special = (char *) pc;
 269         pc->rq = rq;
 270         pc->buffer = buf;
 271         pc->c[0] = REQUEST_SENSE;
 272         pc->c[4] = pc->request_transfer = pc->buffer_size = SCSI_SENSE_BUFFERSIZE;
 273         rq->cmd_type = REQ_TYPE_SENSE;
 274         pc->timeout = jiffies + WAIT_READY;
 275         /* NOTE! Save the failed packet command in "rq->buffer" */
 276         rq->buffer = (void *) failed_command->special;
 277         pc->scsi_cmd = ((idescsi_pc_t *) failed_command->special)->scsi_cmd;
 278         if (test_bit(IDESCSI_LOG_CMD, &scsi->log)) {
 279                 printk ("ide-scsi: %s: queue cmd = ", drive->name);
 280                 ide_scsi_hex_dump(pc->c, 6);
 281         }
 282         rq->rq_disk = scsi->disk;
 283         return ide_do_drive_cmd(drive, rq, ide_preempt);
 284 }
 285
 286 static int idescsi_end_request(ide_drive_t *, int, int);
 287
 288 static ide_startstop_t
 289 idescsi_atapi_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
 290 {
 291         if (HWIF(drive)->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT))
 292                 /* force an abort */
 293                 HWIF(drive)->OUTB(WIN_IDLEIMMEDIATE,IDE_COMMAND_REG);
 294
 295         rq->errors++;
 296
 297         idescsi_end_request(drive, 0, 0);
 298
 299         return ide_stopped;
 300 }
 301
 302 static ide_startstop_t
 303 idescsi_atapi_abort(ide_drive_t *drive, struct request *rq)
 304 {
 305 #if IDESCSI_DEBUG_LOG
 306         printk(KERN_WARNING "idescsi_atapi_abort called for %lu\n",
 307                         ((idescsi_pc_t *) rq->special)->scsi_cmd->serial_number);
 308 #endif
 309         rq->errors |= ERROR_MAX;
 310
 311         idescsi_end_request(drive, 0, 0);
 312
 313         return ide_stopped;
 314 }
 315
 316 static int idescsi_end_request (ide_drive_t *drive, int uptodate, int nrsecs)
 317 {
 318         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
 319         struct request *rq = HWGROUP(drive)->rq;
 320         idescsi_pc_t *pc = (idescsi_pc_t *) rq->special;
 321         int log = test_bit(IDESCSI_LOG_CMD, &scsi->log);
 322         struct Scsi_Host *host;
 323         int errors = rq->errors;
 324         unsigned long flags;
 325
 326         if (!blk_special_request(rq) && !blk_sense_request(rq)) {
 327                 ide_end_request(drive, uptodate, nrsecs);
 328                 return 0;
 329         }
 330         ide_end_drive_cmd (drive, 0, 0);
 331         if (blk_sense_request(rq)) {
 332                 idescsi_pc_t *opc = (idescsi_pc_t *) rq->buffer;
 333                 if (log) {
 334                         printk ("ide-scsi: %s: wrap up check %lu, rst = ", drive->name, opc->scsi_cmd->serial_number);
 335                         ide_scsi_hex_dump(pc->buffer, 16);
 336                 }
 337                 memcpy((void *) opc->scsi_cmd->sense_buffer, pc->buffer, SCSI_SENSE_BUFFERSIZE);
 338                 kfree(pc->buffer);
 339                 kfree(pc);
 340                 kfree(rq);
 341                 pc = opc;
 342                 rq = pc->rq;
 343                 pc->scsi_cmd->result = (CHECK_CONDITION << 1) |
 344                                         ((test_bit(PC_TIMEDOUT, &pc->flags)?DID_TIME_OUT:DID_OK) << 16);
 345         } else if (test_bit(PC_TIMEDOUT, &pc->flags)) {
 346                 if (log)
 347                         printk (KERN_WARNING "ide-scsi: %s: timed out for %lu\n",
 348                                         drive->name, pc->scsi_cmd->serial_number);
 349                 pc->scsi_cmd->result = DID_TIME_OUT << 16;
 350         } else if (errors >= ERROR_MAX) {
 351                 pc->scsi_cmd->result = DID_ERROR << 16;
 352                 if (log)
 353                         printk ("ide-scsi: %s: I/O error for %lu\n", drive->name, pc->scsi_cmd->serial_number);
 354         } else if (errors) {
 355                 if (log)
 356                         printk ("ide-scsi: %s: check condition for %lu\n", drive->name, pc->scsi_cmd->serial_number);
 357                 if (!idescsi_check_condition(drive, rq))
 358                         /* we started a request sense, so we'll be back, exit for now */
 359                         return 0;
 360                 pc->scsi_cmd->result = (CHECK_CONDITION << 1) | (DID_OK << 16);
 361         } else {
 362                 pc->scsi_cmd->result = DID_OK << 16;
 363         }
 364         host = pc->scsi_cmd->device->host;
 365         spin_lock_irqsave(host->host_lock, flags);
 366         pc->done(pc->scsi_cmd);
 367         spin_unlock_irqrestore(host->host_lock, flags);
 368         kfree(pc);
 369         kfree(rq);
 370         scsi->pc = NULL;
 371         return 0;
 372 }
 373
 374 static inline unsigned long get_timeout(idescsi_pc_t *pc)
 375 {
 376         return max_t(unsigned long, WAIT_CMD, pc->timeout - jiffies);
 377 }
 378
 379 static int idescsi_expiry(ide_drive_t *drive)
 380 {
 381         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
 382         idescsi_pc_t   *pc   = scsi->pc;
 383
 384 #if IDESCSI_DEBUG_LOG
 385         printk(KERN_WARNING "idescsi_expiry called for %lu at %lu\n", pc->scsi_cmd->serial_number, jiffies);
 386 #endif
 387         set_bit(PC_TIMEDOUT, &pc->flags);
 388
 389         return 0;                                       /* we do not want the ide subsystem to retry */
 390 }
 391
 392 /*
 393  *      Our interrupt handler.
 394  */
 395 static ide_startstop_t idescsi_pc_intr (ide_drive_t *drive)
 396 {
 397         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
 398         ide_hwif_t *hwif = drive->hwif;
 399         idescsi_pc_t *pc = scsi->pc;
 400         struct request *rq = pc->rq;
 401         unsigned int temp;
 402         u16 bcount;
 403         u8 stat, ireason;
 404
 405 #if IDESCSI_DEBUG_LOG
 406         printk (KERN_INFO "ide-scsi: Reached idescsi_pc_intr interrupt handler\n");
 407 #endif /* IDESCSI_DEBUG_LOG */
 408
 409         if (test_bit(PC_TIMEDOUT, &pc->flags)){
 410 #if IDESCSI_DEBUG_LOG
 411                 printk(KERN_WARNING "idescsi_pc_intr: got timed out packet  %lu at %lu\n",
 412                                 pc->scsi_cmd->serial_number, jiffies);
 413 #endif
 414                 /* end this request now - scsi should retry it*/
 415                 idescsi_end_request (drive, 1, 0);
 416                 return ide_stopped;
 417         }
 418         if (test_and_clear_bit (PC_DMA_IN_PROGRESS, &pc->flags)) {
 419 #if IDESCSI_DEBUG_LOG
 420                 printk ("ide-scsi: %s: DMA complete\n", drive->name);
 421 #endif /* IDESCSI_DEBUG_LOG */
 422                 pc->actually_transferred=pc->request_transfer;
 423                 (void) HWIF(drive)->ide_dma_end(drive);
 424         }
 425
 426         /* Clear the interrupt */
 427         stat = drive->hwif->INB(IDE_STATUS_REG);
 428
 429         if ((stat & DRQ_STAT) == 0) {
 430                 /* No more interrupts */
 431                 if (test_bit(IDESCSI_LOG_CMD, &scsi->log))
 432                         printk (KERN_INFO "Packet command completed, %d bytes transferred\n", pc->actually_transferred);
 433                 local_irq_enable_in_hardirq();
 434                 if (stat & ERR_STAT)
 435                         rq->errors++;
 436                 idescsi_end_request (drive, 1, 0);
 437                 return ide_stopped;
 438         }
 439         bcount = (hwif->INB(IDE_BCOUNTH_REG) << 8) |
 440                   hwif->INB(IDE_BCOUNTL_REG);
 441         ireason = hwif->INB(IDE_IREASON_REG);
 442
 443         if (ireason & CD) {
 444                 printk(KERN_ERR "ide-scsi: CoD != 0 in idescsi_pc_intr\n");
 445                 return ide_do_reset (drive);
 446         }
 447         if (ireason & IO) {
 448                 temp = pc->actually_transferred + bcount;
 449                 if (temp > pc->request_transfer) {
 450                         if (temp > pc->buffer_size) {
 451                                 printk(KERN_ERR "ide-scsi: The scsi wants to "
 452                                         "send us more data than expected "
 453                                         "- discarding data\n");
 454                                 temp = pc->buffer_size - pc->actually_transferred;
 455                                 if (temp) {
 456                                         clear_bit(PC_WRITING, &pc->flags);
 457                                         if (pc->sg)
 458                                                 idescsi_input_buffers(drive, pc, temp);
 459                                         else
 460                                                 drive->hwif->atapi_input_bytes(drive, pc->current_position, temp);
 461                                         printk(KERN_ERR "ide-scsi: transferred"
 462                                                         " %d of %d bytes\n",
 463                                                         temp, bcount);
 464                                 }
 465                                 pc->actually_transferred += temp;
 466                                 pc->current_position += temp;
 467                                 idescsi_discard_data(drive, bcount - temp);
 468                                 ide_set_handler(drive, &idescsi_pc_intr, get_timeout(pc), idescsi_expiry);
 469                                 return ide_started;
 470                         }
 471 #if IDESCSI_DEBUG_LOG
 472                         printk (KERN_NOTICE "ide-scsi: The scsi wants to send us more data than expected - allowing transfer\n");
 473 #endif /* IDESCSI_DEBUG_LOG */
 474                 }
 475         }
 476         if (ireason & IO) {
 477                 clear_bit(PC_WRITING, &pc->flags);
 478                 if (pc->sg)
 479                         idescsi_input_buffers(drive, pc, bcount);
 480                 else
 481                         hwif->atapi_input_bytes(drive, pc->current_position,
 482                                                 bcount);
 483         } else {
 484                 set_bit(PC_WRITING, &pc->flags);
 485                 if (pc->sg)
 486                         idescsi_output_buffers(drive, pc, bcount);
 487                 else
 488                         hwif->atapi_output_bytes(drive, pc->current_position,
 489                                                  bcount);
 490         }
 491         /* Update the current position */
 492         pc->actually_transferred += bcount;
 493         pc->current_position += bcount;
 494
 495         /* And set the interrupt handler again */
 496         ide_set_handler(drive, &idescsi_pc_intr, get_timeout(pc), idescsi_expiry);
 497         return ide_started;
 498 }
 499
 500 static ide_startstop_t idescsi_transfer_pc(ide_drive_t *drive)
 501 {
 502         ide_hwif_t *hwif = drive->hwif;
 503         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
 504         idescsi_pc_t *pc = scsi->pc;
 505         ide_startstop_t startstop;
 506         u8 ireason;
 507
 508         if (ide_wait_stat(&startstop,drive,DRQ_STAT,BUSY_STAT,WAIT_READY)) {
 509                 printk(KERN_ERR "ide-scsi: Strange, packet command "
 510                         "initiated yet DRQ isn't asserted\n");
 511                 return startstop;
 512         }
 513         ireason = hwif->INB(IDE_IREASON_REG);
 514         if ((ireason & CD) == 0 || (ireason & IO)) {
 515                 printk(KERN_ERR "ide-scsi: (IO,CoD) != (0,1) while "
 516                                 "issuing a packet command\n");
 517                 return ide_do_reset (drive);
 518         }
 519         BUG_ON(HWGROUP(drive)->handler != NULL);
 520         /* Set the interrupt routine */
 521         ide_set_handler(drive, &idescsi_pc_intr, get_timeout(pc), idescsi_expiry);
 522         /* Send the actual packet */
 523         drive->hwif->atapi_output_bytes(drive, scsi->pc->c, 12);
 524         if (test_bit (PC_DMA_OK, &pc->flags)) {
 525                 set_bit (PC_DMA_IN_PROGRESS, &pc->flags);
 526                 hwif->dma_start(drive);
 527         }
 528         return ide_started;
 529 }
 530
 531 static inline int idescsi_set_direction(idescsi_pc_t *pc)
 532 {
 533         switch (pc->c[0]) {
 534                 case READ_6: case READ_10: case READ_12:
 535                         clear_bit(PC_WRITING, &pc->flags);
 536                         return 0;
 537                 case WRITE_6: case WRITE_10: case WRITE_12:
 538                         set_bit(PC_WRITING, &pc->flags);
 539                         return 0;
 540                 default:
 541                         return 1;
 542         }
 543 }
 544
 545 static int idescsi_map_sg(ide_drive_t *drive, idescsi_pc_t *pc)
 546 {
 547         ide_hwif_t *hwif = drive->hwif;
 548         struct scatterlist *sg, *scsi_sg;
 549         int segments;
 550
 551         if (!pc->request_transfer || pc->request_transfer % 1024)
 552                 return 1;
 553
 554         if (idescsi_set_direction(pc))
 555                 return 1;
 556
 557         sg = hwif->sg_table;
 558         scsi_sg = scsi_sglist(pc->scsi_cmd);
 559         segments = scsi_sg_count(pc->scsi_cmd);
 560
 561         if (segments > hwif->sg_max_nents)
 562                 return 1;
 563
 564         hwif->sg_nents = segments;
 565         memcpy(sg, scsi_sg, sizeof(*sg) * segments);
 566
 567         return 0;
 568 }
 569
 570 /*
 571  *      Issue a packet command
 572  */
 573 static ide_startstop_t idescsi_issue_pc (ide_drive_t *drive, idescsi_pc_t *pc)
 574 {
 575         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
 576         ide_hwif_t *hwif = drive->hwif;
 577         u16 bcount;
 578         u8 dma = 0;
 579
 580         scsi->pc=pc;                                                    /* Set the current packet command */
 581         pc->actually_transferred=0;                                     /* We haven't transferred any data yet */
 582         pc->current_position=pc->buffer;
 583         /* Request to transfer the entire buffer at once */
 584         bcount = min(pc->request_transfer, 63 * 1024);
 585
 586         if (drive->using_dma && !idescsi_map_sg(drive, pc)) {
 587                 hwif->sg_mapped = 1;
 588                 dma = !hwif->dma_setup(drive);
 589                 hwif->sg_mapped = 0;
 590         }
 591
 592         SELECT_DRIVE(drive);
 593
 594         ide_pktcmd_tf_load(drive, IDE_TFLAG_NO_SELECT_MASK, bcount, dma);
 595
 596         if (dma)
 597                 set_bit(PC_DMA_OK, &pc->flags);
 598
 599         if (test_bit(IDESCSI_DRQ_INTERRUPT, &scsi->flags)) {
 600                 BUG_ON(HWGROUP(drive)->handler != NULL);
 601                 ide_set_handler(drive, &idescsi_transfer_pc,
 602                                 get_timeout(pc), idescsi_expiry);
 603                 /* Issue the packet command */
 604                 HWIF(drive)->OUTB(WIN_PACKETCMD, IDE_COMMAND_REG);
 605                 return ide_started;
 606         } else {
 607                 /* Issue the packet command */
 608                 HWIF(drive)->OUTB(WIN_PACKETCMD, IDE_COMMAND_REG);
 609                 return idescsi_transfer_pc(drive);
 610         }
 611 }
 612
 613 /*
 614  *      idescsi_do_request is our request handling function.
 615  */
 616 static ide_startstop_t idescsi_do_request (ide_drive_t *drive, struct request *rq, sector_t block)
 617 {
 618 #if IDESCSI_DEBUG_LOG
 619         printk (KERN_INFO "dev: %s, cmd: %x, errors: %d\n", rq->rq_disk->disk_name,rq->cmd[0],rq->errors);
 620         printk (KERN_INFO "sector: %ld, nr_sectors: %ld, current_nr_sectors: %d\n",rq->sector,rq->nr_sectors,rq->current_nr_sectors);
 621 #endif /* IDESCSI_DEBUG_LOG */
 622
 623         if (blk_sense_request(rq) || blk_special_request(rq)) {
 624                 return idescsi_issue_pc (drive, (idescsi_pc_t *) rq->special);
 625         }
 626         blk_dump_rq_flags(rq, "ide-scsi: unsup command");
 627         idescsi_end_request (drive, 0, 0);
 628         return ide_stopped;
 629 }
 630
 631 #ifdef CONFIG_IDE_PROC_FS
 632 static void idescsi_add_settings(ide_drive_t *drive)
 633 {
 634         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
 635
 636 /*
 637  *                      drive   setting name    read/write      data type       min     max     mul_factor      div_factor      data pointer            set function
 638  */
 639         ide_add_setting(drive,  "bios_cyl",     SETTING_RW,     TYPE_INT,       0,      1023,   1,              1,              &drive->bios_cyl,       NULL);
 640         ide_add_setting(drive,  "bios_head",    SETTING_RW,     TYPE_BYTE,      0,      255,    1,              1,              &drive->bios_head,      NULL);
 641         ide_add_setting(drive,  "bios_sect",    SETTING_RW,     TYPE_BYTE,      0,      63,     1,              1,              &drive->bios_sect,      NULL);
 642         ide_add_setting(drive,  "transform",    SETTING_RW,     TYPE_INT,       0,      3,      1,              1,              &scsi->transform,       NULL);
 643         ide_add_setting(drive,  "log",          SETTING_RW,     TYPE_INT,       0,      1,      1,              1,              &scsi->log,             NULL);
 644 }
 645 #else
 646 static inline void idescsi_add_settings(ide_drive_t *drive) { ; }
 647 #endif
 648
 649 /*
 650  *      Driver initialization.
 651  */
 652 static void idescsi_setup (ide_drive_t *drive, idescsi_scsi_t *scsi)
 653 {
 654         if (drive->id && (drive->id->config & 0x0060) == 0x20)
 655                 set_bit (IDESCSI_DRQ_INTERRUPT, &scsi->flags);
 656         clear_bit(IDESCSI_SG_TRANSFORM, &scsi->transform);
 657 #if IDESCSI_DEBUG_LOG
 658         set_bit(IDESCSI_LOG_CMD, &scsi->log);
 659 #endif /* IDESCSI_DEBUG_LOG */
 660         idescsi_add_settings(drive);
 661 }
 662
 663 static void ide_scsi_remove(ide_drive_t *drive)
 664 {
 665         struct Scsi_Host *scsihost = drive->driver_data;
 666         struct ide_scsi_obj *scsi = scsihost_to_idescsi(scsihost);
 667         struct gendisk *g = scsi->disk;
 668
 669         scsi_remove_host(scsihost);
 670         ide_proc_unregister_driver(drive, scsi->driver);
 671
 672         ide_unregister_region(g);
 673
 674         drive->driver_data = NULL;
 675         g->private_data = NULL;
 676         put_disk(g);
 677
 678         ide_scsi_put(scsi);
 679 }
 680
 681 static int ide_scsi_probe(ide_drive_t *);
 682
 683 #ifdef CONFIG_IDE_PROC_FS
 684 static ide_proc_entry_t idescsi_proc[] = {
 685         { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL },
 686         { NULL, 0, NULL, NULL }
 687 };
 688 #endif
 689
 690 static ide_driver_t idescsi_driver = {
 691         .gen_driver = {
 692                 .owner          = THIS_MODULE,
 693                 .name           = "ide-scsi",
 694                 .bus            = &ide_bus_type,
 695         },
 696         .probe                  = ide_scsi_probe,
 697         .remove                 = ide_scsi_remove,
 698         .version                = IDESCSI_VERSION,
 699         .media                  = ide_scsi,
 700         .supports_dsc_overlap   = 0,
 701         .do_request             = idescsi_do_request,
 702         .end_request            = idescsi_end_request,
 703         .error                  = idescsi_atapi_error,
 704         .abort                  = idescsi_atapi_abort,
 705 #ifdef CONFIG_IDE_PROC_FS
 706         .proc                   = idescsi_proc,
 707 #endif
 708 };
 709
 710 static int idescsi_ide_open(struct inode *inode, struct file *filp)
 711 {
 712         struct gendisk *disk = inode->i_bdev->bd_disk;
 713         struct ide_scsi_obj *scsi;
 714
 715         if (!(scsi = ide_scsi_get(disk)))
 716                 return -ENXIO;
 717
 718         return 0;
 719 }
 720
 721 static int idescsi_ide_release(struct inode *inode, struct file *filp)
 722 {
 723         struct gendisk *disk = inode->i_bdev->bd_disk;
 724         struct ide_scsi_obj *scsi = ide_scsi_g(disk);
 725
 726         ide_scsi_put(scsi);
 727
 728         return 0;
 729 }
 730
 731 static int idescsi_ide_ioctl(struct inode *inode, struct file *file,
 732                         unsigned int cmd, unsigned long arg)
 733 {
 734         struct block_device *bdev = inode->i_bdev;
 735         struct ide_scsi_obj *scsi = ide_scsi_g(bdev->bd_disk);
 736         return generic_ide_ioctl(scsi->drive, file, bdev, cmd, arg);
 737 }
 738
 739 static struct block_device_operations idescsi_ops = {
 740         .owner          = THIS_MODULE,
 741         .open           = idescsi_ide_open,
 742         .release        = idescsi_ide_release,
 743         .ioctl          = idescsi_ide_ioctl,
 744 };
 745
 746 static int idescsi_slave_configure(struct scsi_device * sdp)
 747 {
 748         /* Configure detected device */
 749         sdp->use_10_for_rw = 1;
 750         sdp->use_10_for_ms = 1;
 751         scsi_adjust_queue_depth(sdp, MSG_SIMPLE_TAG, sdp->host->cmd_per_lun);
 752         return 0;
 753 }
 754
 755 static const char *idescsi_info (struct Scsi_Host *host)
 756 {
 757         return "SCSI host adapter emulation for IDE ATAPI devices";
 758 }
 759
 760 static int idescsi_ioctl (struct scsi_device *dev, int cmd, void __user *arg)
 761 {
 762         idescsi_scsi_t *scsi = scsihost_to_idescsi(dev->host);
 763
 764         if (cmd == SG_SET_TRANSFORM) {
 765                 if (arg)
 766                         set_bit(IDESCSI_SG_TRANSFORM, &scsi->transform);
 767                 else
 768                         clear_bit(IDESCSI_SG_TRANSFORM, &scsi->transform);
 769                 return 0;
 770         } else if (cmd == SG_GET_TRANSFORM)
 771                 return put_user(test_bit(IDESCSI_SG_TRANSFORM, &scsi->transform), (int __user *) arg);
 772         return -EINVAL;
 773 }
 774
 775 static int idescsi_queue (struct scsi_cmnd *cmd,
 776                 void (*done)(struct scsi_cmnd *))
 777 {
 778         struct Scsi_Host *host = cmd->device->host;
 779         idescsi_scsi_t *scsi = scsihost_to_idescsi(host);
 780         ide_drive_t *drive = scsi->drive;
 781         struct request *rq = NULL;
 782         idescsi_pc_t *pc = NULL;
 783
 784         if (!drive) {
 785                 scmd_printk (KERN_ERR, cmd, "drive not present\n");
 786                 goto abort;
 787         }
 788         scsi = drive_to_idescsi(drive);
 789         pc = kmalloc (sizeof (idescsi_pc_t), GFP_ATOMIC);
 790         rq = kmalloc (sizeof (struct request), GFP_ATOMIC);
 791         if (rq == NULL || pc == NULL) {
 792                 printk (KERN_ERR "ide-scsi: %s: out of memory\n", drive->name);
 793                 goto abort;
 794         }
 795
 796         memset (pc->c, 0, 12);
 797         pc->flags = 0;
 798         pc->rq = rq;
 799         memcpy (pc->c, cmd->cmnd, cmd->cmd_len);
 800         pc->buffer = NULL;
 801         pc->sg = scsi_sglist(cmd);
 802         pc->sg_cnt = scsi_sg_count(cmd);
 803         pc->b_count = 0;
 804         pc->request_transfer = pc->buffer_size = scsi_bufflen(cmd);
 805         pc->scsi_cmd = cmd;
 806         pc->done = done;
 807         pc->timeout = jiffies + cmd->timeout_per_command;
 808
 809         if (test_bit(IDESCSI_LOG_CMD, &scsi->log)) {
 810                 printk ("ide-scsi: %s: que %lu, cmd = ", drive->name, cmd->serial_number);
 811                 ide_scsi_hex_dump(cmd->cmnd, cmd->cmd_len);
 812                 if (memcmp(pc->c, cmd->cmnd, cmd->cmd_len)) {
 813                         printk ("ide-scsi: %s: que %lu, tsl = ", drive->name, cmd->serial_number);
 814                         ide_scsi_hex_dump(pc->c, 12);
 815                 }
 816         }
 817
 818         ide_init_drive_cmd (rq);
 819         rq->special = (char *) pc;
 820         rq->cmd_type = REQ_TYPE_SPECIAL;
 821         spin_unlock_irq(host->host_lock);
 822         rq->rq_disk = scsi->disk;
 823         (void) ide_do_drive_cmd (drive, rq, ide_end);
 824         spin_lock_irq(host->host_lock);
 825         return 0;
 826 abort:
 827         kfree (pc);
 828         kfree (rq);
 829         cmd->result = DID_ERROR << 16;
 830         done(cmd);
 831         return 0;
 832 }
 833
 834 static int idescsi_eh_abort (struct scsi_cmnd *cmd)
 835 {
 836         idescsi_scsi_t *scsi  = scsihost_to_idescsi(cmd->device->host);
 837         ide_drive_t    *drive = scsi->drive;
 838         int             busy;
 839         int             ret   = FAILED;
 840
 841         /* In idescsi_eh_abort we try to gently pry our command from the ide subsystem */
 842
 843         if (test_bit(IDESCSI_LOG_CMD, &scsi->log))
 844                 printk (KERN_WARNING "ide-scsi: abort called for %lu\n", cmd->serial_number);
 845
 846         if (!drive) {
 847                 printk (KERN_WARNING "ide-scsi: Drive not set in idescsi_eh_abort\n");
 848                 WARN_ON(1);
 849                 goto no_drive;
 850         }
 851
 852         /* First give it some more time, how much is "right" is hard to say :-( */
 853
 854         busy = ide_wait_not_busy(HWIF(drive), 100);     /* FIXME - uses mdelay which causes latency? */
 855         if (test_bit(IDESCSI_LOG_CMD, &scsi->log))
 856                 printk (KERN_WARNING "ide-scsi: drive did%s become ready\n", busy?" not":"");
 857
 858         spin_lock_irq(&ide_lock);
 859
 860         /* If there is no pc running we're done (our interrupt took care of it) */
 861         if (!scsi->pc) {
 862                 ret = SUCCESS;
 863                 goto ide_unlock;
 864         }
 865
 866         /* It's somewhere in flight. Does ide subsystem agree? */
 867         if (scsi->pc->scsi_cmd->serial_number == cmd->serial_number && !busy &&
 868             elv_queue_empty(drive->queue) && HWGROUP(drive)->rq != scsi->pc->rq) {
 869                 /*
 870                  * FIXME - not sure this condition can ever occur
 871                  */
 872                 printk (KERN_ERR "ide-scsi: cmd aborted!\n");
 873
 874                 if (blk_sense_request(scsi->pc->rq))
 875                         kfree(scsi->pc->buffer);
 876                 kfree(scsi->pc->rq);
 877                 kfree(scsi->pc);
 878                 scsi->pc = NULL;
 879
 880                 ret = SUCCESS;
 881         }
 882
 883 ide_unlock:
 884         spin_unlock_irq(&ide_lock);
 885 no_drive:
 886         if (test_bit(IDESCSI_LOG_CMD, &scsi->log))
 887                 printk (KERN_WARNING "ide-scsi: abort returns %s\n", ret == SUCCESS?"success":"failed");
 888
 889         return ret;
 890 }
 891
 892 static int idescsi_eh_reset (struct scsi_cmnd *cmd)
 893 {
 894         struct request *req;
 895         idescsi_scsi_t *scsi  = scsihost_to_idescsi(cmd->device->host);
 896         ide_drive_t    *drive = scsi->drive;
 897         int             ready = 0;
 898         int             ret   = SUCCESS;
 899
 900         /* In idescsi_eh_reset we forcefully remove the command from the ide subsystem and reset the device. */
 901
 902         if (test_bit(IDESCSI_LOG_CMD, &scsi->log))
 903                 printk (KERN_WARNING "ide-scsi: reset called for %lu\n", cmd->serial_number);
 904
 905         if (!drive) {
 906                 printk (KERN_WARNING "ide-scsi: Drive not set in idescsi_eh_reset\n");
 907                 WARN_ON(1);
 908                 return FAILED;
 909         }
 910
 911         spin_lock_irq(cmd->device->host->host_lock);
 912         spin_lock(&ide_lock);
 913
 914         if (!scsi->pc || (req = scsi->pc->rq) != HWGROUP(drive)->rq || !HWGROUP(drive)->handler) {
 915                 printk (KERN_WARNING "ide-scsi: No active request in idescsi_eh_reset\n");
 916                 spin_unlock(&ide_lock);
 917                 spin_unlock_irq(cmd->device->host->host_lock);
 918                 return FAILED;
 919         }
 920
 921         /* kill current request */
 922         blkdev_dequeue_request(req);
 923         end_that_request_last(req, 0);
 924         if (blk_sense_request(req))
 925                 kfree(scsi->pc->buffer);
 926         kfree(scsi->pc);
 927         scsi->pc = NULL;
 928         kfree(req);
 929
 930         /* now nuke the drive queue */
 931         while ((req = elv_next_request(drive->queue))) {
 932                 blkdev_dequeue_request(req);
 933                 end_that_request_last(req, 0);
 934         }
 935
 936         HWGROUP(drive)->rq = NULL;
 937         HWGROUP(drive)->handler = NULL;
 938         HWGROUP(drive)->busy = 1;               /* will set this to zero when ide reset finished */
 939         spin_unlock(&ide_lock);
 940
 941         ide_do_reset(drive);
 942
 943         /* ide_do_reset starts a polling handler which restarts itself every 50ms until the reset finishes */
 944
 945         do {
 946                 spin_unlock_irq(cmd->device->host->host_lock);
 947                 msleep(50);
 948                 spin_lock_irq(cmd->device->host->host_lock);
 949         } while ( HWGROUP(drive)->handler );
 950
 951         ready = drive_is_ready(drive);
 952         HWGROUP(drive)->busy--;
 953         if (!ready) {
 954                 printk (KERN_ERR "ide-scsi: reset failed!\n");
 955                 ret = FAILED;
 956         }
 957
 958         spin_unlock_irq(cmd->device->host->host_lock);
 959         return ret;
 960 }
 961
 962 static int idescsi_bios(struct scsi_device *sdev, struct block_device *bdev,
 963                 sector_t capacity, int *parm)
 964 {
 965         idescsi_scsi_t *idescsi = scsihost_to_idescsi(sdev->host);
 966         ide_drive_t *drive = idescsi->drive;
 967
 968         if (drive->bios_cyl && drive->bios_head && drive->bios_sect) {
 969                 parm[0] = drive->bios_head;
 970                 parm[1] = drive->bios_sect;
 971                 parm[2] = drive->bios_cyl;
 972         }
 973         return 0;
 974 }
 975
 976 static struct scsi_host_template idescsi_template = {
 977         .module                 = THIS_MODULE,
 978         .name                   = "idescsi",
 979         .info                   = idescsi_info,
 980         .slave_configure        = idescsi_slave_configure,
 981         .ioctl                  = idescsi_ioctl,
 982         .queuecommand           = idescsi_queue,
 983         .eh_abort_handler       = idescsi_eh_abort,
 984         .eh_host_reset_handler  = idescsi_eh_reset,
 985         .bios_param             = idescsi_bios,
 986         .can_queue              = 40,
 987         .this_id                = -1,
 988         .sg_tablesize           = 256,
 989         .cmd_per_lun            = 5,
 990         .max_sectors            = 128,
 991         .use_clustering         = DISABLE_CLUSTERING,
 992         .emulated               = 1,
 993         .proc_name              = "ide-scsi",
 994 };
 995
 996 static int ide_scsi_probe(ide_drive_t *drive)
 997 {
 998         idescsi_scsi_t *idescsi;
 999         struct Scsi_Host *host;
1000         struct gendisk *g;
1001         static int warned;
1002         int err = -ENOMEM;
1003
1004         if (!warned && drive->media == ide_cdrom) {
1005                 printk(KERN_WARNING "ide-scsi is deprecated for cd burning! Use ide-cd and give dev=/dev/hdX as device\n");
1006                 warned = 1;
1007         }
1008
1009         if (idescsi_nocd && drive->media == ide_cdrom)
1010                 return -ENODEV;
1011
1012         if (!strstr("ide-scsi", drive->driver_req) ||
1013             !drive->present ||
1014             drive->media == ide_disk ||
1015             !(host = scsi_host_alloc(&idescsi_template,sizeof(idescsi_scsi_t))))
1016                 return -ENODEV;
1017
1018         g = alloc_disk(1 << PARTN_BITS);
1019         if (!g)
1020                 goto out_host_put;
1021
1022         ide_init_disk(g, drive);
1023
1024         host->max_id = 1;
1025
1026 #if IDESCSI_DEBUG_LOG
1027         if (drive->id->last_lun)
1028                 printk(KERN_NOTICE "%s: id->last_lun=%u\n", drive->name, drive->id->last_lun);
1029 #endif
1030         if ((drive->id->last_lun & 0x7) != 7)
1031                 host->max_lun = (drive->id->last_lun & 0x7) + 1;
1032         else
1033                 host->max_lun = 1;
1034
1035         drive->driver_data = host;
1036         idescsi = scsihost_to_idescsi(host);
1037         idescsi->drive = drive;
1038         idescsi->driver = &idescsi_driver;
1039         idescsi->host = host;
1040         idescsi->disk = g;
1041         g->private_data = &idescsi->driver;
1042         ide_proc_register_driver(drive, &idescsi_driver);
1043         err = 0;
1044         idescsi_setup(drive, idescsi);
1045         g->fops = &idescsi_ops;
1046         ide_register_region(g);
1047         err = scsi_add_host(host, &drive->gendev);
1048         if (!err) {
1049                 scsi_scan_host(host);
1050                 return 0;
1051         }
1052         /* fall through on error */
1053         ide_unregister_region(g);
1054         ide_proc_unregister_driver(drive, &idescsi_driver);
1055
1056         put_disk(g);
1057 out_host_put:
1058         scsi_host_put(host);
1059         return err;
1060 }
1061
1062 static int __init init_idescsi_module(void)
1063 {
1064         return driver_register(&idescsi_driver.gen_driver);
1065 }
1066
1067 static void __exit exit_idescsi_module(void)
1068 {
1069         driver_unregister(&idescsi_driver.gen_driver);
1070 }
1071
1072 module_param(idescsi_nocd, int, 0600);
1073 MODULE_PARM_DESC(idescsi_nocd, "Disable handling of CD-ROMs so they may be driven by ide-cd");
1074 module_init(init_idescsi_module);
1075 module_exit(exit_idescsi_module);
1076 MODULE_LICENSE("GPL");