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Merge branch 'via-velocity' of git://git.kernel.org/pub/scm/linux/kernel/git/romieu...
[linux-2.6] / 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 #if IDESCSI_DEBUG_LOG
64 #define debug_log(fmt, args...) \
65         printk(KERN_INFO "ide-scsi: " fmt, ## args)
66 #else
67 #define debug_log(fmt, args...) do {} while (0)
68 #endif
69
70 /*
71  *      SCSI command transformation layer
72  */
73 #define IDESCSI_SG_TRANSFORM            1       /* /dev/sg transformation */
74
75 /*
76  *      Log flags
77  */
78 #define IDESCSI_LOG_CMD                 0       /* Log SCSI commands */
79
80 typedef struct ide_scsi_obj {
81         ide_drive_t             *drive;
82         ide_driver_t            *driver;
83         struct gendisk          *disk;
84         struct Scsi_Host        *host;
85
86         struct ide_atapi_pc *pc;                /* Current packet command */
87         unsigned long transform;                /* SCSI cmd translation layer */
88         unsigned long log;                      /* log flags */
89 } idescsi_scsi_t;
90
91 static DEFINE_MUTEX(idescsi_ref_mutex);
92 /* Set by module param to skip cd */
93 static int idescsi_nocd;
94
95 #define ide_scsi_g(disk) \
96         container_of((disk)->private_data, struct ide_scsi_obj, driver)
97
98 static struct ide_scsi_obj *ide_scsi_get(struct gendisk *disk)
99 {
100         struct ide_scsi_obj *scsi = NULL;
101
102         mutex_lock(&idescsi_ref_mutex);
103         scsi = ide_scsi_g(disk);
104         if (scsi) {
105                 if (ide_device_get(scsi->drive))
106                         scsi = NULL;
107                 else
108                         scsi_host_get(scsi->host);
109         }
110         mutex_unlock(&idescsi_ref_mutex);
111         return scsi;
112 }
113
114 static void ide_scsi_put(struct ide_scsi_obj *scsi)
115 {
116         ide_drive_t *drive = scsi->drive;
117
118         mutex_lock(&idescsi_ref_mutex);
119         scsi_host_put(scsi->host);
120         ide_device_put(drive);
121         mutex_unlock(&idescsi_ref_mutex);
122 }
123
124 static inline idescsi_scsi_t *scsihost_to_idescsi(struct Scsi_Host *host)
125 {
126         return (idescsi_scsi_t*) (&host[1]);
127 }
128
129 static inline idescsi_scsi_t *drive_to_idescsi(ide_drive_t *ide_drive)
130 {
131         return scsihost_to_idescsi(ide_drive->driver_data);
132 }
133
134 /*
135  *      PIO data transfer routine using the scatter gather table.
136  */
137 static void ide_scsi_io_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
138                                 unsigned int bcount, int write)
139 {
140         ide_hwif_t *hwif = drive->hwif;
141         const struct ide_tp_ops *tp_ops = hwif->tp_ops;
142         xfer_func_t *xf = write ? tp_ops->output_data : tp_ops->input_data;
143         char *buf;
144         int count;
145
146         while (bcount) {
147                 count = min(pc->sg->length - pc->b_count, bcount);
148                 if (PageHighMem(sg_page(pc->sg))) {
149                         unsigned long flags;
150
151                         local_irq_save(flags);
152                         buf = kmap_atomic(sg_page(pc->sg), KM_IRQ0) +
153                                           pc->sg->offset;
154                         xf(drive, NULL, buf + pc->b_count, count);
155                         kunmap_atomic(buf - pc->sg->offset, KM_IRQ0);
156                         local_irq_restore(flags);
157                 } else {
158                         buf = sg_virt(pc->sg);
159                         xf(drive, NULL, buf + pc->b_count, count);
160                 }
161                 bcount -= count; pc->b_count += count;
162                 if (pc->b_count == pc->sg->length) {
163                         if (!--pc->sg_cnt)
164                                 break;
165                         pc->sg = sg_next(pc->sg);
166                         pc->b_count = 0;
167                 }
168         }
169
170         if (bcount) {
171                 printk(KERN_ERR "%s: scatter gather table too small, %s\n",
172                                 drive->name, write ? "padding with zeros"
173                                                    : "discarding data");
174                 ide_pad_transfer(drive, write, bcount);
175         }
176 }
177
178 static void ide_scsi_hex_dump(u8 *data, int len)
179 {
180         print_hex_dump(KERN_CONT, "", DUMP_PREFIX_NONE, 16, 1, data, len, 0);
181 }
182
183 static int idescsi_end_request(ide_drive_t *, int, int);
184
185 static void ide_scsi_callback(ide_drive_t *drive)
186 {
187         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
188         struct ide_atapi_pc *pc = scsi->pc;
189
190         if (pc->flags & PC_FLAG_TIMEDOUT)
191                 debug_log("%s: got timed out packet %lu at %lu\n", __func__,
192                           pc->scsi_cmd->serial_number, jiffies);
193                 /* end this request now - scsi should retry it*/
194         else if (test_bit(IDESCSI_LOG_CMD, &scsi->log))
195                 printk(KERN_INFO "Packet command completed, %d bytes"
196                                  " transferred\n", pc->xferred);
197
198         idescsi_end_request(drive, 1, 0);
199 }
200
201 static int idescsi_check_condition(ide_drive_t *drive,
202                 struct request *failed_cmd)
203 {
204         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
205         struct ide_atapi_pc   *pc;
206         struct request *rq;
207         u8             *buf;
208
209         /* stuff a sense request in front of our current request */
210         pc = kzalloc(sizeof(struct ide_atapi_pc), GFP_ATOMIC);
211         rq = blk_get_request(drive->queue, READ, GFP_ATOMIC);
212         buf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_ATOMIC);
213         if (!pc || !rq || !buf) {
214                 kfree(buf);
215                 if (rq)
216                         blk_put_request(rq);
217                 kfree(pc);
218                 return -ENOMEM;
219         }
220         rq->special = (char *) pc;
221         pc->rq = rq;
222         pc->buf = buf;
223         pc->c[0] = REQUEST_SENSE;
224         pc->c[4] = pc->req_xfer = pc->buf_size = SCSI_SENSE_BUFFERSIZE;
225         rq->cmd_type = REQ_TYPE_SENSE;
226         rq->cmd_flags |= REQ_PREEMPT;
227         pc->timeout = jiffies + WAIT_READY;
228         /* NOTE! Save the failed packet command in "rq->buffer" */
229         rq->buffer = (void *) failed_cmd->special;
230         pc->scsi_cmd = ((struct ide_atapi_pc *) failed_cmd->special)->scsi_cmd;
231         if (test_bit(IDESCSI_LOG_CMD, &scsi->log)) {
232                 printk ("ide-scsi: %s: queue cmd = ", drive->name);
233                 ide_scsi_hex_dump(pc->c, 6);
234         }
235         rq->rq_disk = scsi->disk;
236         rq->ref_count++;
237         memcpy(rq->cmd, pc->c, 12);
238         ide_do_drive_cmd(drive, rq);
239         return 0;
240 }
241
242 static ide_startstop_t
243 idescsi_atapi_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
244 {
245         ide_hwif_t *hwif = drive->hwif;
246
247         if (hwif->tp_ops->read_status(hwif) & (BUSY_STAT | DRQ_STAT))
248                 /* force an abort */
249                 hwif->tp_ops->exec_command(hwif, WIN_IDLEIMMEDIATE);
250
251         rq->errors++;
252
253         idescsi_end_request(drive, 0, 0);
254
255         return ide_stopped;
256 }
257
258 static int idescsi_end_request (ide_drive_t *drive, int uptodate, int nrsecs)
259 {
260         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
261         struct request *rq = HWGROUP(drive)->rq;
262         struct ide_atapi_pc *pc = (struct ide_atapi_pc *) rq->special;
263         int log = test_bit(IDESCSI_LOG_CMD, &scsi->log);
264         struct Scsi_Host *host;
265         int errors = rq->errors;
266         unsigned long flags;
267
268         if (!blk_special_request(rq) && !blk_sense_request(rq)) {
269                 ide_end_request(drive, uptodate, nrsecs);
270                 return 0;
271         }
272         ide_end_drive_cmd (drive, 0, 0);
273         if (blk_sense_request(rq)) {
274                 struct ide_atapi_pc *opc = (struct ide_atapi_pc *) rq->buffer;
275                 if (log) {
276                         printk ("ide-scsi: %s: wrap up check %lu, rst = ", drive->name, opc->scsi_cmd->serial_number);
277                         ide_scsi_hex_dump(pc->buf, 16);
278                 }
279                 memcpy((void *) opc->scsi_cmd->sense_buffer, pc->buf,
280                         SCSI_SENSE_BUFFERSIZE);
281                 kfree(pc->buf);
282                 kfree(pc);
283                 blk_put_request(rq);
284                 pc = opc;
285                 rq = pc->rq;
286                 pc->scsi_cmd->result = (CHECK_CONDITION << 1) |
287                                 (((pc->flags & PC_FLAG_TIMEDOUT) ?
288                                   DID_TIME_OUT :
289                                   DID_OK) << 16);
290         } else if (pc->flags & PC_FLAG_TIMEDOUT) {
291                 if (log)
292                         printk (KERN_WARNING "ide-scsi: %s: timed out for %lu\n",
293                                         drive->name, pc->scsi_cmd->serial_number);
294                 pc->scsi_cmd->result = DID_TIME_OUT << 16;
295         } else if (errors >= ERROR_MAX) {
296                 pc->scsi_cmd->result = DID_ERROR << 16;
297                 if (log)
298                         printk ("ide-scsi: %s: I/O error for %lu\n", drive->name, pc->scsi_cmd->serial_number);
299         } else if (errors) {
300                 if (log)
301                         printk ("ide-scsi: %s: check condition for %lu\n", drive->name, pc->scsi_cmd->serial_number);
302                 if (!idescsi_check_condition(drive, rq))
303                         /* we started a request sense, so we'll be back, exit for now */
304                         return 0;
305                 pc->scsi_cmd->result = (CHECK_CONDITION << 1) | (DID_OK << 16);
306         } else {
307                 pc->scsi_cmd->result = DID_OK << 16;
308         }
309         host = pc->scsi_cmd->device->host;
310         spin_lock_irqsave(host->host_lock, flags);
311         pc->done(pc->scsi_cmd);
312         spin_unlock_irqrestore(host->host_lock, flags);
313         kfree(pc);
314         blk_put_request(rq);
315         scsi->pc = NULL;
316         return 0;
317 }
318
319 static inline unsigned long get_timeout(struct ide_atapi_pc *pc)
320 {
321         return max_t(unsigned long, WAIT_CMD, pc->timeout - jiffies);
322 }
323
324 static int idescsi_expiry(ide_drive_t *drive)
325 {
326         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
327         struct ide_atapi_pc   *pc   = scsi->pc;
328
329         debug_log("%s called for %lu at %lu\n", __func__,
330                   pc->scsi_cmd->serial_number, jiffies);
331
332         pc->flags |= PC_FLAG_TIMEDOUT;
333
334         return 0;                                       /* we do not want the ide subsystem to retry */
335 }
336
337 /*
338  *      Our interrupt handler.
339  */
340 static ide_startstop_t idescsi_pc_intr (ide_drive_t *drive)
341 {
342         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
343         struct ide_atapi_pc *pc = scsi->pc;
344
345         return ide_pc_intr(drive, pc, idescsi_pc_intr, get_timeout(pc),
346                            idescsi_expiry, NULL, NULL, NULL,
347                            ide_scsi_io_buffers);
348 }
349
350 static ide_startstop_t idescsi_transfer_pc(ide_drive_t *drive)
351 {
352         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
353
354         return ide_transfer_pc(drive, scsi->pc, idescsi_pc_intr,
355                                get_timeout(scsi->pc), idescsi_expiry);
356 }
357
358 static inline int idescsi_set_direction(struct ide_atapi_pc *pc)
359 {
360         switch (pc->c[0]) {
361                 case READ_6: case READ_10: case READ_12:
362                         pc->flags &= ~PC_FLAG_WRITING;
363                         return 0;
364                 case WRITE_6: case WRITE_10: case WRITE_12:
365                         pc->flags |= PC_FLAG_WRITING;
366                         return 0;
367                 default:
368                         return 1;
369         }
370 }
371
372 static int idescsi_map_sg(ide_drive_t *drive, struct ide_atapi_pc *pc)
373 {
374         ide_hwif_t *hwif = drive->hwif;
375         struct scatterlist *sg, *scsi_sg;
376         int segments;
377
378         if (!pc->req_xfer || pc->req_xfer % 1024)
379                 return 1;
380
381         if (idescsi_set_direction(pc))
382                 return 1;
383
384         sg = hwif->sg_table;
385         scsi_sg = scsi_sglist(pc->scsi_cmd);
386         segments = scsi_sg_count(pc->scsi_cmd);
387
388         if (segments > hwif->sg_max_nents)
389                 return 1;
390
391         hwif->sg_nents = segments;
392         memcpy(sg, scsi_sg, sizeof(*sg) * segments);
393
394         return 0;
395 }
396
397 static ide_startstop_t idescsi_issue_pc(ide_drive_t *drive,
398                 struct ide_atapi_pc *pc)
399 {
400         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
401
402         /* Set the current packet command */
403         scsi->pc = pc;
404
405         return ide_issue_pc(drive, pc, idescsi_transfer_pc,
406                             get_timeout(pc), idescsi_expiry);
407 }
408
409 /*
410  *      idescsi_do_request is our request handling function.
411  */
412 static ide_startstop_t idescsi_do_request (ide_drive_t *drive, struct request *rq, sector_t block)
413 {
414         debug_log("dev: %s, cmd: %x, errors: %d\n", rq->rq_disk->disk_name,
415                   rq->cmd[0], rq->errors);
416         debug_log("sector: %ld, nr_sectors: %ld, current_nr_sectors: %d\n",
417                   rq->sector, rq->nr_sectors, rq->current_nr_sectors);
418
419         if (blk_sense_request(rq) || blk_special_request(rq)) {
420                 struct ide_atapi_pc *pc = (struct ide_atapi_pc *)rq->special;
421
422                 if (drive->using_dma && !idescsi_map_sg(drive, pc))
423                         pc->flags |= PC_FLAG_DMA_OK;
424
425                 return idescsi_issue_pc(drive, pc);
426         }
427         blk_dump_rq_flags(rq, "ide-scsi: unsup command");
428         idescsi_end_request (drive, 0, 0);
429         return ide_stopped;
430 }
431
432 #ifdef CONFIG_IDE_PROC_FS
433 static void idescsi_add_settings(ide_drive_t *drive)
434 {
435         idescsi_scsi_t *scsi = drive_to_idescsi(drive);
436
437 /*
438  *                      drive   setting name    read/write      data type       min     max     mul_factor      div_factor      data pointer            set function
439  */
440         ide_add_setting(drive,  "bios_cyl",     SETTING_RW,     TYPE_INT,       0,      1023,   1,              1,              &drive->bios_cyl,       NULL);
441         ide_add_setting(drive,  "bios_head",    SETTING_RW,     TYPE_BYTE,      0,      255,    1,              1,              &drive->bios_head,      NULL);
442         ide_add_setting(drive,  "bios_sect",    SETTING_RW,     TYPE_BYTE,      0,      63,     1,              1,              &drive->bios_sect,      NULL);
443         ide_add_setting(drive,  "transform",    SETTING_RW,     TYPE_INT,       0,      3,      1,              1,              &scsi->transform,       NULL);
444         ide_add_setting(drive,  "log",          SETTING_RW,     TYPE_INT,       0,      1,      1,              1,              &scsi->log,             NULL);
445 }
446 #else
447 static inline void idescsi_add_settings(ide_drive_t *drive) { ; }
448 #endif
449
450 /*
451  *      Driver initialization.
452  */
453 static void idescsi_setup (ide_drive_t *drive, idescsi_scsi_t *scsi)
454 {
455         if (drive->id && (drive->id->config & 0x0060) == 0x20)
456                 set_bit(IDE_AFLAG_DRQ_INTERRUPT, &drive->atapi_flags);
457         clear_bit(IDESCSI_SG_TRANSFORM, &scsi->transform);
458 #if IDESCSI_DEBUG_LOG
459         set_bit(IDESCSI_LOG_CMD, &scsi->log);
460 #endif /* IDESCSI_DEBUG_LOG */
461
462         drive->pc_callback = ide_scsi_callback;
463
464         idescsi_add_settings(drive);
465 }
466
467 static void ide_scsi_remove(ide_drive_t *drive)
468 {
469         struct Scsi_Host *scsihost = drive->driver_data;
470         struct ide_scsi_obj *scsi = scsihost_to_idescsi(scsihost);
471         struct gendisk *g = scsi->disk;
472
473         scsi_remove_host(scsihost);
474         ide_proc_unregister_driver(drive, scsi->driver);
475
476         ide_unregister_region(g);
477
478         drive->driver_data = NULL;
479         g->private_data = NULL;
480         put_disk(g);
481
482         ide_scsi_put(scsi);
483
484         drive->scsi = 0;
485 }
486
487 static int ide_scsi_probe(ide_drive_t *);
488
489 #ifdef CONFIG_IDE_PROC_FS
490 static ide_proc_entry_t idescsi_proc[] = {
491         { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL },
492         { NULL, 0, NULL, NULL }
493 };
494 #endif
495
496 static ide_driver_t idescsi_driver = {
497         .gen_driver = {
498                 .owner          = THIS_MODULE,
499                 .name           = "ide-scsi",
500                 .bus            = &ide_bus_type,
501         },
502         .probe                  = ide_scsi_probe,
503         .remove                 = ide_scsi_remove,
504         .version                = IDESCSI_VERSION,
505         .media                  = ide_scsi,
506         .supports_dsc_overlap   = 0,
507         .do_request             = idescsi_do_request,
508         .end_request            = idescsi_end_request,
509         .error                  = idescsi_atapi_error,
510 #ifdef CONFIG_IDE_PROC_FS
511         .proc                   = idescsi_proc,
512 #endif
513 };
514
515 static int idescsi_ide_open(struct inode *inode, struct file *filp)
516 {
517         struct gendisk *disk = inode->i_bdev->bd_disk;
518         struct ide_scsi_obj *scsi;
519
520         if (!(scsi = ide_scsi_get(disk)))
521                 return -ENXIO;
522
523         return 0;
524 }
525
526 static int idescsi_ide_release(struct inode *inode, struct file *filp)
527 {
528         struct gendisk *disk = inode->i_bdev->bd_disk;
529         struct ide_scsi_obj *scsi = ide_scsi_g(disk);
530
531         ide_scsi_put(scsi);
532
533         return 0;
534 }
535
536 static int idescsi_ide_ioctl(struct inode *inode, struct file *file,
537                         unsigned int cmd, unsigned long arg)
538 {
539         struct block_device *bdev = inode->i_bdev;
540         struct ide_scsi_obj *scsi = ide_scsi_g(bdev->bd_disk);
541         return generic_ide_ioctl(scsi->drive, file, bdev, cmd, arg);
542 }
543
544 static struct block_device_operations idescsi_ops = {
545         .owner          = THIS_MODULE,
546         .open           = idescsi_ide_open,
547         .release        = idescsi_ide_release,
548         .ioctl          = idescsi_ide_ioctl,
549 };
550
551 static int idescsi_slave_configure(struct scsi_device * sdp)
552 {
553         /* Configure detected device */
554         sdp->use_10_for_rw = 1;
555         sdp->use_10_for_ms = 1;
556         scsi_adjust_queue_depth(sdp, MSG_SIMPLE_TAG, sdp->host->cmd_per_lun);
557         return 0;
558 }
559
560 static const char *idescsi_info (struct Scsi_Host *host)
561 {
562         return "SCSI host adapter emulation for IDE ATAPI devices";
563 }
564
565 static int idescsi_ioctl (struct scsi_device *dev, int cmd, void __user *arg)
566 {
567         idescsi_scsi_t *scsi = scsihost_to_idescsi(dev->host);
568
569         if (cmd == SG_SET_TRANSFORM) {
570                 if (arg)
571                         set_bit(IDESCSI_SG_TRANSFORM, &scsi->transform);
572                 else
573                         clear_bit(IDESCSI_SG_TRANSFORM, &scsi->transform);
574                 return 0;
575         } else if (cmd == SG_GET_TRANSFORM)
576                 return put_user(test_bit(IDESCSI_SG_TRANSFORM, &scsi->transform), (int __user *) arg);
577         return -EINVAL;
578 }
579
580 static int idescsi_queue (struct scsi_cmnd *cmd,
581                 void (*done)(struct scsi_cmnd *))
582 {
583         struct Scsi_Host *host = cmd->device->host;
584         idescsi_scsi_t *scsi = scsihost_to_idescsi(host);
585         ide_drive_t *drive = scsi->drive;
586         struct request *rq = NULL;
587         struct ide_atapi_pc *pc = NULL;
588         int write = cmd->sc_data_direction == DMA_TO_DEVICE;
589
590         if (!drive) {
591                 scmd_printk (KERN_ERR, cmd, "drive not present\n");
592                 goto abort;
593         }
594         scsi = drive_to_idescsi(drive);
595         pc = kmalloc(sizeof(struct ide_atapi_pc), GFP_ATOMIC);
596         rq = blk_get_request(drive->queue, write, GFP_ATOMIC);
597         if (rq == NULL || pc == NULL) {
598                 printk (KERN_ERR "ide-scsi: %s: out of memory\n", drive->name);
599                 goto abort;
600         }
601
602         memset (pc->c, 0, 12);
603         pc->flags = 0;
604         if (cmd->sc_data_direction == DMA_TO_DEVICE)
605                 pc->flags |= PC_FLAG_WRITING;
606         pc->rq = rq;
607         memcpy (pc->c, cmd->cmnd, cmd->cmd_len);
608         pc->buf = NULL;
609         pc->sg = scsi_sglist(cmd);
610         pc->sg_cnt = scsi_sg_count(cmd);
611         pc->b_count = 0;
612         pc->req_xfer = pc->buf_size = scsi_bufflen(cmd);
613         pc->scsi_cmd = cmd;
614         pc->done = done;
615         pc->timeout = jiffies + cmd->timeout_per_command;
616
617         if (test_bit(IDESCSI_LOG_CMD, &scsi->log)) {
618                 printk ("ide-scsi: %s: que %lu, cmd = ", drive->name, cmd->serial_number);
619                 ide_scsi_hex_dump(cmd->cmnd, cmd->cmd_len);
620                 if (memcmp(pc->c, cmd->cmnd, cmd->cmd_len)) {
621                         printk ("ide-scsi: %s: que %lu, tsl = ", drive->name, cmd->serial_number);
622                         ide_scsi_hex_dump(pc->c, 12);
623                 }
624         }
625
626         rq->special = (char *) pc;
627         rq->cmd_type = REQ_TYPE_SPECIAL;
628         spin_unlock_irq(host->host_lock);
629         rq->ref_count++;
630         memcpy(rq->cmd, pc->c, 12);
631         blk_execute_rq_nowait(drive->queue, scsi->disk, rq, 0, NULL);
632         spin_lock_irq(host->host_lock);
633         return 0;
634 abort:
635         kfree (pc);
636         if (rq)
637                 blk_put_request(rq);
638         cmd->result = DID_ERROR << 16;
639         done(cmd);
640         return 0;
641 }
642
643 static int idescsi_eh_abort (struct scsi_cmnd *cmd)
644 {
645         idescsi_scsi_t *scsi  = scsihost_to_idescsi(cmd->device->host);
646         ide_drive_t    *drive = scsi->drive;
647         int             busy;
648         int             ret   = FAILED;
649
650         /* In idescsi_eh_abort we try to gently pry our command from the ide subsystem */
651
652         if (test_bit(IDESCSI_LOG_CMD, &scsi->log))
653                 printk (KERN_WARNING "ide-scsi: abort called for %lu\n", cmd->serial_number);
654
655         if (!drive) {
656                 printk (KERN_WARNING "ide-scsi: Drive not set in idescsi_eh_abort\n");
657                 WARN_ON(1);
658                 goto no_drive;
659         }
660
661         /* First give it some more time, how much is "right" is hard to say :-( */
662
663         busy = ide_wait_not_busy(HWIF(drive), 100);     /* FIXME - uses mdelay which causes latency? */
664         if (test_bit(IDESCSI_LOG_CMD, &scsi->log))
665                 printk (KERN_WARNING "ide-scsi: drive did%s become ready\n", busy?" not":"");
666
667         spin_lock_irq(&ide_lock);
668
669         /* If there is no pc running we're done (our interrupt took care of it) */
670         if (!scsi->pc) {
671                 ret = SUCCESS;
672                 goto ide_unlock;
673         }
674
675         /* It's somewhere in flight. Does ide subsystem agree? */
676         if (scsi->pc->scsi_cmd->serial_number == cmd->serial_number && !busy &&
677             elv_queue_empty(drive->queue) && HWGROUP(drive)->rq != scsi->pc->rq) {
678                 /*
679                  * FIXME - not sure this condition can ever occur
680                  */
681                 printk (KERN_ERR "ide-scsi: cmd aborted!\n");
682
683                 if (blk_sense_request(scsi->pc->rq))
684                         kfree(scsi->pc->buf);
685                 /* we need to call blk_put_request twice. */
686                 blk_put_request(scsi->pc->rq);
687                 blk_put_request(scsi->pc->rq);
688                 kfree(scsi->pc);
689                 scsi->pc = NULL;
690
691                 ret = SUCCESS;
692         }
693
694 ide_unlock:
695         spin_unlock_irq(&ide_lock);
696 no_drive:
697         if (test_bit(IDESCSI_LOG_CMD, &scsi->log))
698                 printk (KERN_WARNING "ide-scsi: abort returns %s\n", ret == SUCCESS?"success":"failed");
699
700         return ret;
701 }
702
703 static int idescsi_eh_reset (struct scsi_cmnd *cmd)
704 {
705         struct request *req;
706         idescsi_scsi_t *scsi  = scsihost_to_idescsi(cmd->device->host);
707         ide_drive_t    *drive = scsi->drive;
708         int             ready = 0;
709         int             ret   = SUCCESS;
710
711         /* In idescsi_eh_reset we forcefully remove the command from the ide subsystem and reset the device. */
712
713         if (test_bit(IDESCSI_LOG_CMD, &scsi->log))
714                 printk (KERN_WARNING "ide-scsi: reset called for %lu\n", cmd->serial_number);
715
716         if (!drive) {
717                 printk (KERN_WARNING "ide-scsi: Drive not set in idescsi_eh_reset\n");
718                 WARN_ON(1);
719                 return FAILED;
720         }
721
722         spin_lock_irq(cmd->device->host->host_lock);
723         spin_lock(&ide_lock);
724
725         if (!scsi->pc || (req = scsi->pc->rq) != HWGROUP(drive)->rq || !HWGROUP(drive)->handler) {
726                 printk (KERN_WARNING "ide-scsi: No active request in idescsi_eh_reset\n");
727                 spin_unlock(&ide_lock);
728                 spin_unlock_irq(cmd->device->host->host_lock);
729                 return FAILED;
730         }
731
732         /* kill current request */
733         if (__blk_end_request(req, -EIO, 0))
734                 BUG();
735         if (blk_sense_request(req))
736                 kfree(scsi->pc->buf);
737         kfree(scsi->pc);
738         scsi->pc = NULL;
739         blk_put_request(req);
740
741         /* now nuke the drive queue */
742         while ((req = elv_next_request(drive->queue))) {
743                 if (__blk_end_request(req, -EIO, 0))
744                         BUG();
745         }
746
747         HWGROUP(drive)->rq = NULL;
748         HWGROUP(drive)->handler = NULL;
749         HWGROUP(drive)->busy = 1;               /* will set this to zero when ide reset finished */
750         spin_unlock(&ide_lock);
751
752         ide_do_reset(drive);
753
754         /* ide_do_reset starts a polling handler which restarts itself every 50ms until the reset finishes */
755
756         do {
757                 spin_unlock_irq(cmd->device->host->host_lock);
758                 msleep(50);
759                 spin_lock_irq(cmd->device->host->host_lock);
760         } while ( HWGROUP(drive)->handler );
761
762         ready = drive_is_ready(drive);
763         HWGROUP(drive)->busy--;
764         if (!ready) {
765                 printk (KERN_ERR "ide-scsi: reset failed!\n");
766                 ret = FAILED;
767         }
768
769         spin_unlock_irq(cmd->device->host->host_lock);
770         return ret;
771 }
772
773 static int idescsi_bios(struct scsi_device *sdev, struct block_device *bdev,
774                 sector_t capacity, int *parm)
775 {
776         idescsi_scsi_t *idescsi = scsihost_to_idescsi(sdev->host);
777         ide_drive_t *drive = idescsi->drive;
778
779         if (drive->bios_cyl && drive->bios_head && drive->bios_sect) {
780                 parm[0] = drive->bios_head;
781                 parm[1] = drive->bios_sect;
782                 parm[2] = drive->bios_cyl;
783         }
784         return 0;
785 }
786
787 static struct scsi_host_template idescsi_template = {
788         .module                 = THIS_MODULE,
789         .name                   = "idescsi",
790         .info                   = idescsi_info,
791         .slave_configure        = idescsi_slave_configure,
792         .ioctl                  = idescsi_ioctl,
793         .queuecommand           = idescsi_queue,
794         .eh_abort_handler       = idescsi_eh_abort,
795         .eh_host_reset_handler  = idescsi_eh_reset,
796         .bios_param             = idescsi_bios,
797         .can_queue              = 40,
798         .this_id                = -1,
799         .sg_tablesize           = 256,
800         .cmd_per_lun            = 5,
801         .max_sectors            = 128,
802         .use_clustering         = DISABLE_CLUSTERING,
803         .emulated               = 1,
804         .proc_name              = "ide-scsi",
805 };
806
807 static int ide_scsi_probe(ide_drive_t *drive)
808 {
809         idescsi_scsi_t *idescsi;
810         struct Scsi_Host *host;
811         struct gendisk *g;
812         static int warned;
813         int err = -ENOMEM;
814
815         if (!warned && drive->media == ide_cdrom) {
816                 printk(KERN_WARNING "ide-scsi is deprecated for cd burning! Use ide-cd and give dev=/dev/hdX as device\n");
817                 warned = 1;
818         }
819
820         if (idescsi_nocd && drive->media == ide_cdrom)
821                 return -ENODEV;
822
823         if (!strstr("ide-scsi", drive->driver_req) ||
824             !drive->present ||
825             drive->media == ide_disk ||
826             !(host = scsi_host_alloc(&idescsi_template,sizeof(idescsi_scsi_t))))
827                 return -ENODEV;
828
829         drive->scsi = 1;
830
831         g = alloc_disk(1 << PARTN_BITS);
832         if (!g)
833                 goto out_host_put;
834
835         ide_init_disk(g, drive);
836
837         host->max_id = 1;
838
839         if (drive->id->last_lun)
840                 debug_log("%s: id->last_lun=%u\n", drive->name,
841                           drive->id->last_lun);
842
843         if ((drive->id->last_lun & 0x7) != 7)
844                 host->max_lun = (drive->id->last_lun & 0x7) + 1;
845         else
846                 host->max_lun = 1;
847
848         drive->driver_data = host;
849         idescsi = scsihost_to_idescsi(host);
850         idescsi->drive = drive;
851         idescsi->driver = &idescsi_driver;
852         idescsi->host = host;
853         idescsi->disk = g;
854         g->private_data = &idescsi->driver;
855         ide_proc_register_driver(drive, &idescsi_driver);
856         err = 0;
857         idescsi_setup(drive, idescsi);
858         g->fops = &idescsi_ops;
859         ide_register_region(g);
860         err = scsi_add_host(host, &drive->gendev);
861         if (!err) {
862                 scsi_scan_host(host);
863                 return 0;
864         }
865         /* fall through on error */
866         ide_unregister_region(g);
867         ide_proc_unregister_driver(drive, &idescsi_driver);
868
869         put_disk(g);
870 out_host_put:
871         drive->scsi = 0;
872         scsi_host_put(host);
873         return err;
874 }
875
876 static int __init init_idescsi_module(void)
877 {
878         return driver_register(&idescsi_driver.gen_driver);
879 }
880
881 static void __exit exit_idescsi_module(void)
882 {
883         driver_unregister(&idescsi_driver.gen_driver);
884 }
885
886 module_param(idescsi_nocd, int, 0600);
887 MODULE_PARM_DESC(idescsi_nocd, "Disable handling of CD-ROMs so they may be driven by ide-cd");
888 module_init(init_idescsi_module);
889 module_exit(exit_idescsi_module);
890 MODULE_LICENSE("GPL");