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