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