Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-fixes
[linux-2.6] / drivers / block / cciss_scsi.c
1 /*
2  *    Disk Array driver for HP Smart Array controllers, SCSI Tape module.
3  *    (C) Copyright 2001, 2007 Hewlett-Packard Development Company, L.P.
4  *
5  *    This program is free software; you can redistribute it and/or modify
6  *    it under the terms of the GNU General Public License as published by
7  *    the Free Software Foundation; version 2 of the License.
8  *
9  *    This program is distributed in the hope that it will be useful,
10  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
11  *    MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  *    General Public License for more details.
13  *
14  *    You should have received a copy of the GNU General Public License
15  *    along with this program; if not, write to the Free Software
16  *    Foundation, Inc., 59 Temple Place, Suite 300, Boston, MA
17  *    02111-1307, USA.
18  *
19  *    Questions/Comments/Bugfixes to iss_storagedev@hp.com
20  *    
21  *    Author: Stephen M. Cameron
22  */
23 #ifdef CONFIG_CISS_SCSI_TAPE
24
25 /* Here we have code to present the driver as a scsi driver 
26    as it is simultaneously presented as a block driver.  The 
27    reason for doing this is to allow access to SCSI tape drives
28    through the array controller.  Note in particular, neither 
29    physical nor logical disks are presented through the scsi layer. */
30
31 #include <linux/timer.h>
32 #include <linux/completion.h>
33 #include <linux/slab.h>
34 #include <linux/string.h>
35
36 #include <asm/atomic.h>
37
38 #include <scsi/scsi_cmnd.h>
39 #include <scsi/scsi_device.h>
40 #include <scsi/scsi_host.h> 
41
42 #include "cciss_scsi.h"
43
44 #define CCISS_ABORT_MSG 0x00
45 #define CCISS_RESET_MSG 0x01
46
47 /* some prototypes... */ 
48 static int sendcmd(
49         __u8    cmd,
50         int     ctlr,
51         void    *buff,
52         size_t  size,
53         unsigned int use_unit_num, /* 0: address the controller,
54                                       1: address logical volume log_unit, 
55                                       2: address is in scsi3addr */
56         unsigned int log_unit,
57         __u8    page_code,
58         unsigned char *scsi3addr,
59         int cmd_type);
60
61
62 static int cciss_scsi_proc_info(
63                 struct Scsi_Host *sh,
64                 char *buffer, /* data buffer */
65                 char **start,      /* where data in buffer starts */
66                 off_t offset,      /* offset from start of imaginary file */
67                 int length,        /* length of data in buffer */
68                 int func);         /* 0 == read, 1 == write */
69
70 static int cciss_scsi_queue_command (struct scsi_cmnd *cmd,
71                 void (* done)(struct scsi_cmnd *));
72 static int cciss_eh_device_reset_handler(struct scsi_cmnd *);
73 static int cciss_eh_abort_handler(struct scsi_cmnd *);
74
75 static struct cciss_scsi_hba_t ccissscsi[MAX_CTLR] = {
76         { .name = "cciss0", .ndevices = 0 },
77         { .name = "cciss1", .ndevices = 0 },
78         { .name = "cciss2", .ndevices = 0 },
79         { .name = "cciss3", .ndevices = 0 },
80         { .name = "cciss4", .ndevices = 0 },
81         { .name = "cciss5", .ndevices = 0 },
82         { .name = "cciss6", .ndevices = 0 },
83         { .name = "cciss7", .ndevices = 0 },
84 };
85
86 static struct scsi_host_template cciss_driver_template = {
87         .module                 = THIS_MODULE,
88         .name                   = "cciss",
89         .proc_name              = "cciss",
90         .proc_info              = cciss_scsi_proc_info,
91         .queuecommand           = cciss_scsi_queue_command,
92         .can_queue              = SCSI_CCISS_CAN_QUEUE,
93         .this_id                = 7,
94         .sg_tablesize           = MAXSGENTRIES,
95         .cmd_per_lun            = 1,
96         .use_clustering         = DISABLE_CLUSTERING,
97         /* Can't have eh_bus_reset_handler or eh_host_reset_handler for cciss */
98         .eh_device_reset_handler= cciss_eh_device_reset_handler,
99         .eh_abort_handler       = cciss_eh_abort_handler,
100 };
101
102 #pragma pack(1)
103 struct cciss_scsi_cmd_stack_elem_t {
104         CommandList_struct cmd;
105         ErrorInfo_struct Err;
106         __u32 busaddr;
107         __u32 pad;
108 };
109
110 #pragma pack()
111
112 #define CMD_STACK_SIZE (SCSI_CCISS_CAN_QUEUE * \
113                 CCISS_MAX_SCSI_DEVS_PER_HBA + 2)
114                         // plus two for init time usage
115
116 #pragma pack(1)
117 struct cciss_scsi_cmd_stack_t {
118         struct cciss_scsi_cmd_stack_elem_t *pool;
119         struct cciss_scsi_cmd_stack_elem_t *elem[CMD_STACK_SIZE];
120         dma_addr_t cmd_pool_handle;
121         int top;
122 };
123 #pragma pack()
124
125 struct cciss_scsi_adapter_data_t {
126         struct Scsi_Host *scsi_host;
127         struct cciss_scsi_cmd_stack_t cmd_stack;
128         int registered;
129         spinlock_t lock; // to protect ccissscsi[ctlr]; 
130 };
131
132 #define CPQ_TAPE_LOCK(ctlr, flags) spin_lock_irqsave( \
133         &(((struct cciss_scsi_adapter_data_t *) \
134         hba[ctlr]->scsi_ctlr)->lock), flags);
135 #define CPQ_TAPE_UNLOCK(ctlr, flags) spin_unlock_irqrestore( \
136         &(((struct cciss_scsi_adapter_data_t *) \
137         hba[ctlr]->scsi_ctlr)->lock), flags);
138
139 static CommandList_struct *
140 scsi_cmd_alloc(ctlr_info_t *h)
141 {
142         /* assume only one process in here at a time, locking done by caller. */
143         /* use CCISS_LOCK(ctlr) */
144         /* might be better to rewrite how we allocate scsi commands in a way that */
145         /* needs no locking at all. */
146
147         /* take the top memory chunk off the stack and return it, if any. */
148         struct cciss_scsi_cmd_stack_elem_t *c;
149         struct cciss_scsi_adapter_data_t *sa;
150         struct cciss_scsi_cmd_stack_t *stk;
151         u64bit temp64;
152
153         sa = (struct cciss_scsi_adapter_data_t *) h->scsi_ctlr;
154         stk = &sa->cmd_stack; 
155
156         if (stk->top < 0) 
157                 return NULL;
158         c = stk->elem[stk->top];        
159         /* memset(c, 0, sizeof(*c)); */
160         memset(&c->cmd, 0, sizeof(c->cmd));
161         memset(&c->Err, 0, sizeof(c->Err));
162         /* set physical addr of cmd and addr of scsi parameters */
163         c->cmd.busaddr = c->busaddr; 
164         /* (__u32) (stk->cmd_pool_handle + 
165                 (sizeof(struct cciss_scsi_cmd_stack_elem_t)*stk->top)); */
166
167         temp64.val = (__u64) (c->busaddr + sizeof(CommandList_struct));
168         /* (__u64) (stk->cmd_pool_handle + 
169                 (sizeof(struct cciss_scsi_cmd_stack_elem_t)*stk->top) +
170                  sizeof(CommandList_struct)); */
171         stk->top--;
172         c->cmd.ErrDesc.Addr.lower = temp64.val32.lower;
173         c->cmd.ErrDesc.Addr.upper = temp64.val32.upper;
174         c->cmd.ErrDesc.Len = sizeof(ErrorInfo_struct);
175         
176         c->cmd.ctlr = h->ctlr;
177         c->cmd.err_info = &c->Err;
178
179         return (CommandList_struct *) c;
180 }
181
182 static void 
183 scsi_cmd_free(ctlr_info_t *h, CommandList_struct *cmd)
184 {
185         /* assume only one process in here at a time, locking done by caller. */
186         /* use CCISS_LOCK(ctlr) */
187         /* drop the free memory chunk on top of the stack. */
188
189         struct cciss_scsi_adapter_data_t *sa;
190         struct cciss_scsi_cmd_stack_t *stk;
191
192         sa = (struct cciss_scsi_adapter_data_t *) h->scsi_ctlr;
193         stk = &sa->cmd_stack; 
194         if (stk->top >= CMD_STACK_SIZE) {
195                 printk("cciss: scsi_cmd_free called too many times.\n");
196                 BUG();
197         }
198         stk->top++;
199         stk->elem[stk->top] = (struct cciss_scsi_cmd_stack_elem_t *) cmd;
200 }
201
202 static int
203 scsi_cmd_stack_setup(int ctlr, struct cciss_scsi_adapter_data_t *sa)
204 {
205         int i;
206         struct cciss_scsi_cmd_stack_t *stk;
207         size_t size;
208
209         stk = &sa->cmd_stack; 
210         size = sizeof(struct cciss_scsi_cmd_stack_elem_t) * CMD_STACK_SIZE;
211
212         // pci_alloc_consistent guarantees 32-bit DMA address will
213         // be used
214
215         stk->pool = (struct cciss_scsi_cmd_stack_elem_t *)
216                 pci_alloc_consistent(hba[ctlr]->pdev, size, &stk->cmd_pool_handle);
217
218         if (stk->pool == NULL) {
219                 printk("stk->pool is null\n");
220                 return -1;
221         }
222
223         for (i=0; i<CMD_STACK_SIZE; i++) {
224                 stk->elem[i] = &stk->pool[i];
225                 stk->elem[i]->busaddr = (__u32) (stk->cmd_pool_handle + 
226                         (sizeof(struct cciss_scsi_cmd_stack_elem_t) * i));
227         }
228         stk->top = CMD_STACK_SIZE-1;
229         return 0;
230 }
231
232 static void
233 scsi_cmd_stack_free(int ctlr)
234 {
235         struct cciss_scsi_adapter_data_t *sa;
236         struct cciss_scsi_cmd_stack_t *stk;
237         size_t size;
238
239         sa = (struct cciss_scsi_adapter_data_t *) hba[ctlr]->scsi_ctlr;
240         stk = &sa->cmd_stack; 
241         if (stk->top != CMD_STACK_SIZE-1) {
242                 printk( "cciss: %d scsi commands are still outstanding.\n",
243                         CMD_STACK_SIZE - stk->top);
244                 // BUG();
245                 printk("WE HAVE A BUG HERE!!! stk=0x%p\n", stk);
246         }
247         size = sizeof(struct cciss_scsi_cmd_stack_elem_t) * CMD_STACK_SIZE;
248
249         pci_free_consistent(hba[ctlr]->pdev, size, stk->pool, stk->cmd_pool_handle);
250         stk->pool = NULL;
251 }
252
253 #if 0
254 static int xmargin=8;
255 static int amargin=60;
256
257 static void
258 print_bytes (unsigned char *c, int len, int hex, int ascii)
259 {
260
261         int i;
262         unsigned char *x;
263
264         if (hex)
265         {
266                 x = c;
267                 for (i=0;i<len;i++)
268                 {
269                         if ((i % xmargin) == 0 && i>0) printk("\n");
270                         if ((i % xmargin) == 0) printk("0x%04x:", i);
271                         printk(" %02x", *x);
272                         x++;
273                 }
274                 printk("\n");
275         }
276         if (ascii)
277         {
278                 x = c;
279                 for (i=0;i<len;i++)
280                 {
281                         if ((i % amargin) == 0 && i>0) printk("\n");
282                         if ((i % amargin) == 0) printk("0x%04x:", i);
283                         if (*x > 26 && *x < 128) printk("%c", *x);
284                         else printk(".");
285                         x++;
286                 }
287                 printk("\n");
288         }
289 }
290
291 static void
292 print_cmd(CommandList_struct *cp)
293 {
294         printk("queue:%d\n", cp->Header.ReplyQueue);
295         printk("sglist:%d\n", cp->Header.SGList);
296         printk("sgtot:%d\n", cp->Header.SGTotal);
297         printk("Tag:0x%08x/0x%08x\n", cp->Header.Tag.upper, 
298                         cp->Header.Tag.lower);
299         printk("LUN:0x%02x%02x%02x%02x%02x%02x%02x%02x\n",
300                 cp->Header.LUN.LunAddrBytes[0],
301                 cp->Header.LUN.LunAddrBytes[1],
302                 cp->Header.LUN.LunAddrBytes[2],
303                 cp->Header.LUN.LunAddrBytes[3],
304                 cp->Header.LUN.LunAddrBytes[4],
305                 cp->Header.LUN.LunAddrBytes[5],
306                 cp->Header.LUN.LunAddrBytes[6],
307                 cp->Header.LUN.LunAddrBytes[7]);
308         printk("CDBLen:%d\n", cp->Request.CDBLen);
309         printk("Type:%d\n",cp->Request.Type.Type);
310         printk("Attr:%d\n",cp->Request.Type.Attribute);
311         printk(" Dir:%d\n",cp->Request.Type.Direction);
312         printk("Timeout:%d\n",cp->Request.Timeout);
313         printk( "CDB: %02x %02x %02x %02x %02x %02x %02x %02x"
314                 " %02x %02x %02x %02x %02x %02x %02x %02x\n",
315                 cp->Request.CDB[0], cp->Request.CDB[1],
316                 cp->Request.CDB[2], cp->Request.CDB[3],
317                 cp->Request.CDB[4], cp->Request.CDB[5],
318                 cp->Request.CDB[6], cp->Request.CDB[7],
319                 cp->Request.CDB[8], cp->Request.CDB[9],
320                 cp->Request.CDB[10], cp->Request.CDB[11],
321                 cp->Request.CDB[12], cp->Request.CDB[13],
322                 cp->Request.CDB[14], cp->Request.CDB[15]),
323         printk("edesc.Addr: 0x%08x/0%08x, Len  = %d\n", 
324                 cp->ErrDesc.Addr.upper, cp->ErrDesc.Addr.lower, 
325                         cp->ErrDesc.Len);
326         printk("sgs..........Errorinfo:\n");
327         printk("scsistatus:%d\n", cp->err_info->ScsiStatus);
328         printk("senselen:%d\n", cp->err_info->SenseLen);
329         printk("cmd status:%d\n", cp->err_info->CommandStatus);
330         printk("resid cnt:%d\n", cp->err_info->ResidualCnt);
331         printk("offense size:%d\n", cp->err_info->MoreErrInfo.Invalid_Cmd.offense_size);
332         printk("offense byte:%d\n", cp->err_info->MoreErrInfo.Invalid_Cmd.offense_num);
333         printk("offense value:%d\n", cp->err_info->MoreErrInfo.Invalid_Cmd.offense_value);
334                         
335 }
336
337 #endif
338
339 static int 
340 find_bus_target_lun(int ctlr, int *bus, int *target, int *lun)
341 {
342         /* finds an unused bus, target, lun for a new device */
343         /* assumes hba[ctlr]->scsi_ctlr->lock is held */ 
344         int i, found=0;
345         unsigned char target_taken[CCISS_MAX_SCSI_DEVS_PER_HBA];
346
347         memset(&target_taken[0], 0, CCISS_MAX_SCSI_DEVS_PER_HBA);
348
349         target_taken[SELF_SCSI_ID] = 1; 
350         for (i=0;i<ccissscsi[ctlr].ndevices;i++)
351                 target_taken[ccissscsi[ctlr].dev[i].target] = 1;
352         
353         for (i=0;i<CCISS_MAX_SCSI_DEVS_PER_HBA;i++) {
354                 if (!target_taken[i]) {
355                         *bus = 0; *target=i; *lun = 0; found=1;
356                         break;
357                 }
358         }
359         return (!found);        
360 }
361
362 static int 
363 cciss_scsi_add_entry(int ctlr, int hostno, 
364                 unsigned char *scsi3addr, int devtype)
365 {
366         /* assumes hba[ctlr]->scsi_ctlr->lock is held */ 
367         int n = ccissscsi[ctlr].ndevices;
368         struct cciss_scsi_dev_t *sd;
369
370         if (n >= CCISS_MAX_SCSI_DEVS_PER_HBA) {
371                 printk("cciss%d: Too many devices, "
372                         "some will be inaccessible.\n", ctlr);
373                 return -1;
374         }
375         sd = &ccissscsi[ctlr].dev[n];
376         if (find_bus_target_lun(ctlr, &sd->bus, &sd->target, &sd->lun) != 0)
377                 return -1;
378         memcpy(&sd->scsi3addr[0], scsi3addr, 8);
379         sd->devtype = devtype;
380         ccissscsi[ctlr].ndevices++;
381
382         /* initially, (before registering with scsi layer) we don't 
383            know our hostno and we don't want to print anything first 
384            time anyway (the scsi layer's inquiries will show that info) */
385         if (hostno != -1)
386                 printk("cciss%d: %s device c%db%dt%dl%d added.\n", 
387                         ctlr, scsi_device_type(sd->devtype), hostno,
388                         sd->bus, sd->target, sd->lun);
389         return 0;
390 }
391
392 static void
393 cciss_scsi_remove_entry(int ctlr, int hostno, int entry)
394 {
395         /* assumes hba[ctlr]->scsi_ctlr->lock is held */ 
396         int i;
397         struct cciss_scsi_dev_t sd;
398
399         if (entry < 0 || entry >= CCISS_MAX_SCSI_DEVS_PER_HBA) return;
400         sd = ccissscsi[ctlr].dev[entry];
401         for (i=entry;i<ccissscsi[ctlr].ndevices-1;i++)
402                 ccissscsi[ctlr].dev[i] = ccissscsi[ctlr].dev[i+1];
403         ccissscsi[ctlr].ndevices--;
404         printk("cciss%d: %s device c%db%dt%dl%d removed.\n",
405                 ctlr, scsi_device_type(sd.devtype), hostno,
406                         sd.bus, sd.target, sd.lun);
407 }
408
409
410 #define SCSI3ADDR_EQ(a,b) ( \
411         (a)[7] == (b)[7] && \
412         (a)[6] == (b)[6] && \
413         (a)[5] == (b)[5] && \
414         (a)[4] == (b)[4] && \
415         (a)[3] == (b)[3] && \
416         (a)[2] == (b)[2] && \
417         (a)[1] == (b)[1] && \
418         (a)[0] == (b)[0])
419
420 static int
421 adjust_cciss_scsi_table(int ctlr, int hostno,
422         struct cciss_scsi_dev_t sd[], int nsds)
423 {
424         /* sd contains scsi3 addresses and devtypes, but
425            bus target and lun are not filled in.  This funciton
426            takes what's in sd to be the current and adjusts
427            ccissscsi[] to be in line with what's in sd. */ 
428
429         int i,j, found, changes=0;
430         struct cciss_scsi_dev_t *csd;
431         unsigned long flags;
432
433         CPQ_TAPE_LOCK(ctlr, flags);
434
435         /* find any devices in ccissscsi[] that are not in 
436            sd[] and remove them from ccissscsi[] */
437
438         i = 0;
439         while(i<ccissscsi[ctlr].ndevices) {
440                 csd = &ccissscsi[ctlr].dev[i];
441                 found=0;
442                 for (j=0;j<nsds;j++) {
443                         if (SCSI3ADDR_EQ(sd[j].scsi3addr,
444                                 csd->scsi3addr)) {
445                                 if (sd[j].devtype == csd->devtype)
446                                         found=2;
447                                 else
448                                         found=1;
449                                 break;
450                         }
451                 }
452
453                 if (found == 0) { /* device no longer present. */ 
454                         changes++;
455                         /* printk("cciss%d: %s device c%db%dt%dl%d removed.\n",
456                                 ctlr, scsi_device_type(csd->devtype), hostno,
457                                         csd->bus, csd->target, csd->lun); */
458                         cciss_scsi_remove_entry(ctlr, hostno, i);
459                         /* note, i not incremented */
460                 } 
461                 else if (found == 1) { /* device is different kind */
462                         changes++;
463                         printk("cciss%d: device c%db%dt%dl%d type changed "
464                                 "(device type now %s).\n",
465                                 ctlr, hostno, csd->bus, csd->target, csd->lun,
466                                         scsi_device_type(csd->devtype));
467                         csd->devtype = sd[j].devtype;
468                         i++;    /* so just move along. */
469                 } else          /* device is same as it ever was, */
470                         i++;    /* so just move along. */
471         }
472
473         /* Now, make sure every device listed in sd[] is also
474            listed in ccissscsi[], adding them if they aren't found */
475
476         for (i=0;i<nsds;i++) {
477                 found=0;
478                 for (j=0;j<ccissscsi[ctlr].ndevices;j++) {
479                         csd = &ccissscsi[ctlr].dev[j];
480                         if (SCSI3ADDR_EQ(sd[i].scsi3addr,
481                                 csd->scsi3addr)) {
482                                 if (sd[i].devtype == csd->devtype)
483                                         found=2;        /* found device */
484                                 else
485                                         found=1;        /* found a bug. */
486                                 break;
487                         }
488                 }
489                 if (!found) {
490                         changes++;
491                         if (cciss_scsi_add_entry(ctlr, hostno, 
492                                 &sd[i].scsi3addr[0], sd[i].devtype) != 0)
493                                 break;
494                 } else if (found == 1) {
495                         /* should never happen... */
496                         changes++;
497                         printk("cciss%d: device unexpectedly changed type\n",
498                                 ctlr);
499                         /* but if it does happen, we just ignore that device */
500                 }
501         }
502         CPQ_TAPE_UNLOCK(ctlr, flags);
503
504         if (!changes) 
505                 printk("cciss%d: No device changes detected.\n", ctlr);
506
507         return 0;
508 }
509
510 static int
511 lookup_scsi3addr(int ctlr, int bus, int target, int lun, char *scsi3addr)
512 {
513         int i;
514         struct cciss_scsi_dev_t *sd;
515         unsigned long flags;
516
517         CPQ_TAPE_LOCK(ctlr, flags);
518         for (i=0;i<ccissscsi[ctlr].ndevices;i++) {
519                 sd = &ccissscsi[ctlr].dev[i];
520                 if (sd->bus == bus &&
521                     sd->target == target &&
522                     sd->lun == lun) {
523                         memcpy(scsi3addr, &sd->scsi3addr[0], 8);
524                         CPQ_TAPE_UNLOCK(ctlr, flags);
525                         return 0;
526                 }
527         }
528         CPQ_TAPE_UNLOCK(ctlr, flags);
529         return -1;
530 }
531
532 static void 
533 cciss_scsi_setup(int cntl_num)
534 {
535         struct cciss_scsi_adapter_data_t * shba;
536
537         ccissscsi[cntl_num].ndevices = 0;
538         shba = (struct cciss_scsi_adapter_data_t *)
539                 kmalloc(sizeof(*shba), GFP_KERNEL);     
540         if (shba == NULL)
541                 return;
542         shba->scsi_host = NULL;
543         spin_lock_init(&shba->lock);
544         shba->registered = 0;
545         if (scsi_cmd_stack_setup(cntl_num, shba) != 0) {
546                 kfree(shba);
547                 shba = NULL;
548         }
549         hba[cntl_num]->scsi_ctlr = (void *) shba;
550         return;
551 }
552
553 static void
554 complete_scsi_command( CommandList_struct *cp, int timeout, __u32 tag)
555 {
556         struct scsi_cmnd *cmd;
557         ctlr_info_t *ctlr;
558         ErrorInfo_struct *ei;
559
560         ei = cp->err_info;
561
562         /* First, see if it was a message rather than a command */
563         if (cp->Request.Type.Type == TYPE_MSG)  {
564                 cp->cmd_type = CMD_MSG_DONE;
565                 return;
566         }
567
568         cmd = (struct scsi_cmnd *) cp->scsi_cmd;        
569         ctlr = hba[cp->ctlr];
570
571         scsi_dma_unmap(cmd);
572
573         cmd->result = (DID_OK << 16);           /* host byte */
574         cmd->result |= (COMMAND_COMPLETE << 8); /* msg byte */
575         /* cmd->result |= (GOOD < 1); */                /* status byte */
576
577         cmd->result |= (ei->ScsiStatus);
578         /* printk("Scsistatus is 0x%02x\n", ei->ScsiStatus);  */
579
580         /* copy the sense data whether we need to or not. */
581
582         memcpy(cmd->sense_buffer, ei->SenseInfo, 
583                 ei->SenseLen > SCSI_SENSE_BUFFERSIZE ?
584                         SCSI_SENSE_BUFFERSIZE : 
585                         ei->SenseLen);
586         scsi_set_resid(cmd, ei->ResidualCnt);
587
588         if(ei->CommandStatus != 0) 
589         { /* an error has occurred */ 
590                 switch(ei->CommandStatus)
591                 {
592                         case CMD_TARGET_STATUS:
593                                 /* Pass it up to the upper layers... */
594                                 if( ei->ScsiStatus)
595                                 {
596 #if 0
597                                         printk(KERN_WARNING "cciss: cmd %p "
598                                         "has SCSI Status = %x\n",
599                                                 cp,  
600                                                 ei->ScsiStatus); 
601 #endif
602                                         cmd->result |= (ei->ScsiStatus < 1);
603                                 }
604                                 else {  /* scsi status is zero??? How??? */
605                                         
606         /* Ordinarily, this case should never happen, but there is a bug
607            in some released firmware revisions that allows it to happen
608            if, for example, a 4100 backplane loses power and the tape
609            drive is in it.  We assume that it's a fatal error of some
610            kind because we can't show that it wasn't. We will make it
611            look like selection timeout since that is the most common
612            reason for this to occur, and it's severe enough. */
613
614                                         cmd->result = DID_NO_CONNECT << 16;
615                                 }
616                         break;
617                         case CMD_DATA_UNDERRUN: /* let mid layer handle it. */
618                         break;
619                         case CMD_DATA_OVERRUN:
620                                 printk(KERN_WARNING "cciss: cp %p has"
621                                         " completed with data overrun "
622                                         "reported\n", cp);
623                         break;
624                         case CMD_INVALID: {
625                                 /* print_bytes(cp, sizeof(*cp), 1, 0);
626                                 print_cmd(cp); */
627      /* We get CMD_INVALID if you address a non-existent tape drive instead
628         of a selection timeout (no response).  You will see this if you yank 
629         out a tape drive, then try to access it. This is kind of a shame
630         because it means that any other CMD_INVALID (e.g. driver bug) will
631         get interpreted as a missing target. */
632                                 cmd->result = DID_NO_CONNECT << 16;
633                                 }
634                         break;
635                         case CMD_PROTOCOL_ERR:
636                                 printk(KERN_WARNING "cciss: cp %p has "
637                                         "protocol error \n", cp);
638                         break;
639                         case CMD_HARDWARE_ERR:
640                                 cmd->result = DID_ERROR << 16;
641                                 printk(KERN_WARNING "cciss: cp %p had " 
642                                         " hardware error\n", cp);
643                         break;
644                         case CMD_CONNECTION_LOST:
645                                 cmd->result = DID_ERROR << 16;
646                                 printk(KERN_WARNING "cciss: cp %p had "
647                                         "connection lost\n", cp);
648                         break;
649                         case CMD_ABORTED:
650                                 cmd->result = DID_ABORT << 16;
651                                 printk(KERN_WARNING "cciss: cp %p was "
652                                         "aborted\n", cp);
653                         break;
654                         case CMD_ABORT_FAILED:
655                                 cmd->result = DID_ERROR << 16;
656                                 printk(KERN_WARNING "cciss: cp %p reports "
657                                         "abort failed\n", cp);
658                         break;
659                         case CMD_UNSOLICITED_ABORT:
660                                 cmd->result = DID_ABORT << 16;
661                                 printk(KERN_WARNING "cciss: cp %p aborted "
662                                         "do to an unsolicited abort\n", cp);
663                         break;
664                         case CMD_TIMEOUT:
665                                 cmd->result = DID_TIME_OUT << 16;
666                                 printk(KERN_WARNING "cciss: cp %p timedout\n",
667                                         cp);
668                         break;
669                         default:
670                                 cmd->result = DID_ERROR << 16;
671                                 printk(KERN_WARNING "cciss: cp %p returned "
672                                         "unknown status %x\n", cp, 
673                                                 ei->CommandStatus); 
674                 }
675         }
676         // printk("c:%p:c%db%dt%dl%d ", cmd, ctlr->ctlr, cmd->channel, 
677         //      cmd->target, cmd->lun);
678         cmd->scsi_done(cmd);
679         scsi_cmd_free(ctlr, cp);
680 }
681
682 static int
683 cciss_scsi_detect(int ctlr)
684 {
685         struct Scsi_Host *sh;
686         int error;
687
688         sh = scsi_host_alloc(&cciss_driver_template, sizeof(struct ctlr_info *));
689         if (sh == NULL)
690                 goto fail;
691         sh->io_port = 0;        // good enough?  FIXME, 
692         sh->n_io_port = 0;      // I don't think we use these two...
693         sh->this_id = SELF_SCSI_ID;  
694
695         ((struct cciss_scsi_adapter_data_t *) 
696                 hba[ctlr]->scsi_ctlr)->scsi_host = (void *) sh;
697         sh->hostdata[0] = (unsigned long) hba[ctlr];
698         sh->irq = hba[ctlr]->intr[SIMPLE_MODE_INT];
699         sh->unique_id = sh->irq;
700         error = scsi_add_host(sh, &hba[ctlr]->pdev->dev);
701         if (error)
702                 goto fail_host_put;
703         scsi_scan_host(sh);
704         return 1;
705
706  fail_host_put:
707         scsi_host_put(sh);
708  fail:
709         return 0;
710 }
711
712 static void
713 cciss_unmap_one(struct pci_dev *pdev,
714                 CommandList_struct *cp,
715                 size_t buflen,
716                 int data_direction)
717 {
718         u64bit addr64;
719
720         addr64.val32.lower = cp->SG[0].Addr.lower;
721         addr64.val32.upper = cp->SG[0].Addr.upper;
722         pci_unmap_single(pdev, (dma_addr_t) addr64.val, buflen, data_direction);
723 }
724
725 static void
726 cciss_map_one(struct pci_dev *pdev,
727                 CommandList_struct *cp,
728                 unsigned char *buf,
729                 size_t buflen,
730                 int data_direction)
731 {
732         __u64 addr64;
733
734         addr64 = (__u64) pci_map_single(pdev, buf, buflen, data_direction);
735         cp->SG[0].Addr.lower = 
736           (__u32) (addr64 & (__u64) 0x00000000FFFFFFFF);
737         cp->SG[0].Addr.upper =
738           (__u32) ((addr64 >> 32) & (__u64) 0x00000000FFFFFFFF);
739         cp->SG[0].Len = buflen;
740         cp->Header.SGList = (__u8) 1;   /* no. SGs contig in this cmd */
741         cp->Header.SGTotal = (__u16) 1; /* total sgs in this cmd list */
742 }
743
744 static int
745 cciss_scsi_do_simple_cmd(ctlr_info_t *c,
746                         CommandList_struct *cp,
747                         unsigned char *scsi3addr, 
748                         unsigned char *cdb,
749                         unsigned char cdblen,
750                         unsigned char *buf, int bufsize,
751                         int direction)
752 {
753         unsigned long flags;
754         DECLARE_COMPLETION_ONSTACK(wait);
755
756         cp->cmd_type = CMD_IOCTL_PEND;          // treat this like an ioctl 
757         cp->scsi_cmd = NULL;
758         cp->Header.ReplyQueue = 0;  // unused in simple mode
759         memcpy(&cp->Header.LUN, scsi3addr, sizeof(cp->Header.LUN));
760         cp->Header.Tag.lower = cp->busaddr;  // Use k. address of cmd as tag
761         // Fill in the request block...
762
763         /* printk("Using scsi3addr 0x%02x%0x2%0x2%0x2%0x2%0x2%0x2%0x2\n", 
764                 scsi3addr[0], scsi3addr[1], scsi3addr[2], scsi3addr[3],
765                 scsi3addr[4], scsi3addr[5], scsi3addr[6], scsi3addr[7]); */
766
767         memset(cp->Request.CDB, 0, sizeof(cp->Request.CDB));
768         memcpy(cp->Request.CDB, cdb, cdblen);
769         cp->Request.Timeout = 0;
770         cp->Request.CDBLen = cdblen;
771         cp->Request.Type.Type = TYPE_CMD;
772         cp->Request.Type.Attribute = ATTR_SIMPLE;
773         cp->Request.Type.Direction = direction;
774
775         /* Fill in the SG list and do dma mapping */
776         cciss_map_one(c->pdev, cp, (unsigned char *) buf,
777                         bufsize, DMA_FROM_DEVICE); 
778
779         cp->waiting = &wait;
780
781         /* Put the request on the tail of the request queue */
782         spin_lock_irqsave(CCISS_LOCK(c->ctlr), flags);
783         addQ(&c->reqQ, cp);
784         c->Qdepth++;
785         start_io(c);
786         spin_unlock_irqrestore(CCISS_LOCK(c->ctlr), flags);
787
788         wait_for_completion(&wait);
789
790         /* undo the dma mapping */
791         cciss_unmap_one(c->pdev, cp, bufsize, DMA_FROM_DEVICE);
792         return(0);
793 }
794
795 static void 
796 cciss_scsi_interpret_error(CommandList_struct *cp)
797 {
798         ErrorInfo_struct *ei;
799
800         ei = cp->err_info; 
801         switch(ei->CommandStatus)
802         {
803                 case CMD_TARGET_STATUS:
804                         printk(KERN_WARNING "cciss: cmd %p has "
805                                 "completed with errors\n", cp);
806                         printk(KERN_WARNING "cciss: cmd %p "
807                                 "has SCSI Status = %x\n",
808                                         cp,  
809                                         ei->ScsiStatus);
810                         if (ei->ScsiStatus == 0)
811                                 printk(KERN_WARNING 
812                                 "cciss:SCSI status is abnormally zero.  "
813                                 "(probably indicates selection timeout "
814                                 "reported incorrectly due to a known "
815                                 "firmware bug, circa July, 2001.)\n");
816                 break;
817                 case CMD_DATA_UNDERRUN: /* let mid layer handle it. */
818                         printk("UNDERRUN\n");
819                 break;
820                 case CMD_DATA_OVERRUN:
821                         printk(KERN_WARNING "cciss: cp %p has"
822                                 " completed with data overrun "
823                                 "reported\n", cp);
824                 break;
825                 case CMD_INVALID: {
826                         /* controller unfortunately reports SCSI passthru's */
827                         /* to non-existent targets as invalid commands. */
828                         printk(KERN_WARNING "cciss: cp %p is "
829                                 "reported invalid (probably means "
830                                 "target device no longer present)\n", 
831                                 cp); 
832                         /* print_bytes((unsigned char *) cp, sizeof(*cp), 1, 0);
833                         print_cmd(cp);  */
834                         }
835                 break;
836                 case CMD_PROTOCOL_ERR:
837                         printk(KERN_WARNING "cciss: cp %p has "
838                                 "protocol error \n", cp);
839                 break;
840                 case CMD_HARDWARE_ERR:
841                         /* cmd->result = DID_ERROR << 16; */
842                         printk(KERN_WARNING "cciss: cp %p had " 
843                                 " hardware error\n", cp);
844                 break;
845                 case CMD_CONNECTION_LOST:
846                         printk(KERN_WARNING "cciss: cp %p had "
847                                 "connection lost\n", cp);
848                 break;
849                 case CMD_ABORTED:
850                         printk(KERN_WARNING "cciss: cp %p was "
851                                 "aborted\n", cp);
852                 break;
853                 case CMD_ABORT_FAILED:
854                         printk(KERN_WARNING "cciss: cp %p reports "
855                                 "abort failed\n", cp);
856                 break;
857                 case CMD_UNSOLICITED_ABORT:
858                         printk(KERN_WARNING "cciss: cp %p aborted "
859                                 "do to an unsolicited abort\n", cp);
860                 break;
861                 case CMD_TIMEOUT:
862                         printk(KERN_WARNING "cciss: cp %p timedout\n",
863                                 cp);
864                 break;
865                 default:
866                         printk(KERN_WARNING "cciss: cp %p returned "
867                                 "unknown status %x\n", cp, 
868                                         ei->CommandStatus); 
869         }
870 }
871
872 static int
873 cciss_scsi_do_inquiry(ctlr_info_t *c, unsigned char *scsi3addr, 
874                  unsigned char *buf, unsigned char bufsize)
875 {
876         int rc;
877         CommandList_struct *cp;
878         char cdb[6];
879         ErrorInfo_struct *ei;
880         unsigned long flags;
881
882         spin_lock_irqsave(CCISS_LOCK(c->ctlr), flags);
883         cp = scsi_cmd_alloc(c);
884         spin_unlock_irqrestore(CCISS_LOCK(c->ctlr), flags);
885
886         if (cp == NULL) {                       /* trouble... */
887                 printk("cmd_alloc returned NULL!\n");
888                 return -1;
889         }
890
891         ei = cp->err_info; 
892
893         cdb[0] = CISS_INQUIRY;
894         cdb[1] = 0;
895         cdb[2] = 0;
896         cdb[3] = 0;
897         cdb[4] = bufsize;
898         cdb[5] = 0;
899         rc = cciss_scsi_do_simple_cmd(c, cp, scsi3addr, cdb, 
900                                 6, buf, bufsize, XFER_READ);
901
902         if (rc != 0) return rc; /* something went wrong */
903
904         if (ei->CommandStatus != 0 && 
905             ei->CommandStatus != CMD_DATA_UNDERRUN) {
906                 cciss_scsi_interpret_error(cp);
907                 rc = -1;
908         }
909         spin_lock_irqsave(CCISS_LOCK(c->ctlr), flags);
910         scsi_cmd_free(c, cp);
911         spin_unlock_irqrestore(CCISS_LOCK(c->ctlr), flags);
912         return rc;      
913 }
914
915 static int
916 cciss_scsi_do_report_phys_luns(ctlr_info_t *c, 
917                 ReportLunData_struct *buf, int bufsize)
918 {
919         int rc;
920         CommandList_struct *cp;
921         unsigned char cdb[12];
922         unsigned char scsi3addr[8]; 
923         ErrorInfo_struct *ei;
924         unsigned long flags;
925
926         spin_lock_irqsave(CCISS_LOCK(c->ctlr), flags);
927         cp = scsi_cmd_alloc(c);
928         spin_unlock_irqrestore(CCISS_LOCK(c->ctlr), flags);
929         if (cp == NULL) {                       /* trouble... */
930                 printk("cmd_alloc returned NULL!\n");
931                 return -1;
932         }
933
934         memset(&scsi3addr[0], 0, 8); /* address the controller */
935         cdb[0] = CISS_REPORT_PHYS;
936         cdb[1] = 0;
937         cdb[2] = 0;
938         cdb[3] = 0;
939         cdb[4] = 0;
940         cdb[5] = 0;
941         cdb[6] = (bufsize >> 24) & 0xFF;  //MSB
942         cdb[7] = (bufsize >> 16) & 0xFF;
943         cdb[8] = (bufsize >> 8) & 0xFF;
944         cdb[9] = bufsize & 0xFF;
945         cdb[10] = 0;
946         cdb[11] = 0;
947
948         rc = cciss_scsi_do_simple_cmd(c, cp, scsi3addr, 
949                                 cdb, 12, 
950                                 (unsigned char *) buf, 
951                                 bufsize, XFER_READ);
952
953         if (rc != 0) return rc; /* something went wrong */
954
955         ei = cp->err_info; 
956         if (ei->CommandStatus != 0 && 
957             ei->CommandStatus != CMD_DATA_UNDERRUN) {
958                 cciss_scsi_interpret_error(cp);
959                 rc = -1;
960         }
961         spin_lock_irqsave(CCISS_LOCK(c->ctlr), flags);
962         scsi_cmd_free(c, cp);
963         spin_unlock_irqrestore(CCISS_LOCK(c->ctlr), flags);
964         return rc;      
965 }
966
967 static void
968 cciss_update_non_disk_devices(int cntl_num, int hostno)
969 {
970         /* the idea here is we could get notified from /proc
971            that some devices have changed, so we do a report 
972            physical luns cmd, and adjust our list of devices 
973            accordingly.  (We can't rely on the scsi-mid layer just
974            doing inquiries, because the "busses" that the scsi 
975            mid-layer probes are totally fabricated by this driver,
976            so new devices wouldn't show up.
977
978            the scsi3addr's of devices won't change so long as the 
979            adapter is not reset.  That means we can rescan and 
980            tell which devices we already know about, vs. new 
981            devices, vs.  disappearing devices.
982
983            Also, if you yank out a tape drive, then put in a disk
984            in it's place, (say, a configured volume from another 
985            array controller for instance)  _don't_ poke this driver 
986            (so it thinks it's still a tape, but _do_ poke the scsi 
987            mid layer, so it does an inquiry... the scsi mid layer 
988            will see the physical disk.  This would be bad.  Need to
989            think about how to prevent that.  One idea would be to 
990            snoop all scsi responses and if an inquiry repsonse comes
991            back that reports a disk, chuck it an return selection
992            timeout instead and adjust our table...  Not sure i like
993            that though.  
994
995          */
996 #define OBDR_TAPE_INQ_SIZE 49
997 #define OBDR_TAPE_SIG "$DR-10"
998         ReportLunData_struct *ld_buff;
999         unsigned char *inq_buff;
1000         unsigned char scsi3addr[8];
1001         ctlr_info_t *c;
1002         __u32 num_luns=0;
1003         unsigned char *ch;
1004         /* unsigned char found[CCISS_MAX_SCSI_DEVS_PER_HBA]; */
1005         struct cciss_scsi_dev_t currentsd[CCISS_MAX_SCSI_DEVS_PER_HBA];
1006         int ncurrent=0;
1007         int reportlunsize = sizeof(*ld_buff) + CISS_MAX_PHYS_LUN * 8;
1008         int i;
1009
1010         c = (ctlr_info_t *) hba[cntl_num];      
1011         ld_buff = kzalloc(reportlunsize, GFP_KERNEL);
1012         if (ld_buff == NULL) {
1013                 printk(KERN_ERR "cciss: out of memory\n");
1014                 return;
1015         }
1016         inq_buff = kmalloc(OBDR_TAPE_INQ_SIZE, GFP_KERNEL);
1017         if (inq_buff == NULL) {
1018                 printk(KERN_ERR "cciss: out of memory\n");
1019                 kfree(ld_buff);
1020                 return;
1021         }
1022
1023         if (cciss_scsi_do_report_phys_luns(c, ld_buff, reportlunsize) == 0) {
1024                 ch = &ld_buff->LUNListLength[0];
1025                 num_luns = ((ch[0]<<24) | (ch[1]<<16) | (ch[2]<<8) | ch[3]) / 8;
1026                 if (num_luns > CISS_MAX_PHYS_LUN) {
1027                         printk(KERN_WARNING 
1028                                 "cciss: Maximum physical LUNs (%d) exceeded.  "
1029                                 "%d LUNs ignored.\n", CISS_MAX_PHYS_LUN, 
1030                                 num_luns - CISS_MAX_PHYS_LUN);
1031                         num_luns = CISS_MAX_PHYS_LUN;
1032                 }
1033         }
1034         else {
1035                 printk(KERN_ERR  "cciss: Report physical LUNs failed.\n");
1036                 goto out;
1037         }
1038
1039
1040         /* adjust our table of devices */       
1041         for(i=0; i<num_luns; i++)
1042         {
1043                 int devtype;
1044
1045                 /* for each physical lun, do an inquiry */
1046                 if (ld_buff->LUN[i][3] & 0xC0) continue;
1047                 memset(inq_buff, 0, OBDR_TAPE_INQ_SIZE);
1048                 memcpy(&scsi3addr[0], &ld_buff->LUN[i][0], 8);
1049
1050                 if (cciss_scsi_do_inquiry(hba[cntl_num], scsi3addr, inq_buff,
1051                         (unsigned char) OBDR_TAPE_INQ_SIZE) != 0) {
1052                         /* Inquiry failed (msg printed already) */
1053                         devtype = 0; /* so we will skip this device. */
1054                 } else /* what kind of device is this? */
1055                         devtype = (inq_buff[0] & 0x1f);
1056
1057                 switch (devtype)
1058                 {
1059                   case 0x05: /* CD-ROM */ {
1060
1061                         /* We don't *really* support actual CD-ROM devices,
1062                          * just this "One Button Disaster Recovery" tape drive
1063                          * which temporarily pretends to be a CD-ROM drive.
1064                          * So we check that the device is really an OBDR tape
1065                          * device by checking for "$DR-10" in bytes 43-48 of
1066                          * the inquiry data.
1067                          */
1068                                 char obdr_sig[7];
1069
1070                                 strncpy(obdr_sig, &inq_buff[43], 6);
1071                                 obdr_sig[6] = '\0';
1072                                 if (strncmp(obdr_sig, OBDR_TAPE_SIG, 6) != 0)
1073                                         /* Not OBDR device, ignore it. */
1074                                         break;
1075                         }
1076                         /* fall through . . . */
1077                   case 0x01: /* sequential access, (tape) */
1078                   case 0x08: /* medium changer */
1079                         if (ncurrent >= CCISS_MAX_SCSI_DEVS_PER_HBA) {
1080                                 printk(KERN_INFO "cciss%d: %s ignored, "
1081                                         "too many devices.\n", cntl_num,
1082                                         scsi_device_type(devtype));
1083                                 break;
1084                         }
1085                         memcpy(&currentsd[ncurrent].scsi3addr[0], 
1086                                 &scsi3addr[0], 8);
1087                         currentsd[ncurrent].devtype = devtype;
1088                         currentsd[ncurrent].bus = -1;
1089                         currentsd[ncurrent].target = -1;
1090                         currentsd[ncurrent].lun = -1;
1091                         ncurrent++;
1092                         break;
1093                   default: 
1094                         break;
1095                 }
1096         }
1097
1098         adjust_cciss_scsi_table(cntl_num, hostno, currentsd, ncurrent);
1099 out:
1100         kfree(inq_buff);
1101         kfree(ld_buff);
1102         return;
1103 }
1104
1105 static int
1106 is_keyword(char *ptr, int len, char *verb)  // Thanks to ncr53c8xx.c
1107 {
1108         int verb_len = strlen(verb);
1109         if (len >= verb_len && !memcmp(verb,ptr,verb_len))
1110                 return verb_len;
1111         else
1112                 return 0;
1113 }
1114
1115 static int
1116 cciss_scsi_user_command(int ctlr, int hostno, char *buffer, int length)
1117 {
1118         int arg_len;
1119
1120         if ((arg_len = is_keyword(buffer, length, "rescan")) != 0)
1121                 cciss_update_non_disk_devices(ctlr, hostno);
1122         else
1123                 return -EINVAL;
1124         return length;
1125 }
1126
1127
1128 static int
1129 cciss_scsi_proc_info(struct Scsi_Host *sh,
1130                 char *buffer, /* data buffer */
1131                 char **start,      /* where data in buffer starts */
1132                 off_t offset,      /* offset from start of imaginary file */
1133                 int length,        /* length of data in buffer */
1134                 int func)          /* 0 == read, 1 == write */
1135 {
1136
1137         int buflen, datalen;
1138         ctlr_info_t *ci;
1139         int i;
1140         int cntl_num;
1141
1142
1143         ci = (ctlr_info_t *) sh->hostdata[0];
1144         if (ci == NULL)  /* This really shouldn't ever happen. */
1145                 return -EINVAL;
1146
1147         cntl_num = ci->ctlr;    /* Get our index into the hba[] array */
1148
1149         if (func == 0) {        /* User is reading from /proc/scsi/ciss*?/?*  */
1150                 buflen = sprintf(buffer, "cciss%d: SCSI host: %d\n",
1151                                 cntl_num, sh->host_no);
1152
1153                 /* this information is needed by apps to know which cciss
1154                    device corresponds to which scsi host number without
1155                    having to open a scsi target device node.  The device
1156                    information is not a duplicate of /proc/scsi/scsi because
1157                    the two may be out of sync due to scsi hotplug, rather
1158                    this info is for an app to be able to use to know how to
1159                    get them back in sync. */
1160
1161                 for (i=0;i<ccissscsi[cntl_num].ndevices;i++) {
1162                         struct cciss_scsi_dev_t *sd = &ccissscsi[cntl_num].dev[i];
1163                         buflen += sprintf(&buffer[buflen], "c%db%dt%dl%d %02d "
1164                                 "0x%02x%02x%02x%02x%02x%02x%02x%02x\n",
1165                                 sh->host_no, sd->bus, sd->target, sd->lun,
1166                                 sd->devtype,
1167                                 sd->scsi3addr[0], sd->scsi3addr[1],
1168                                 sd->scsi3addr[2], sd->scsi3addr[3],
1169                                 sd->scsi3addr[4], sd->scsi3addr[5],
1170                                 sd->scsi3addr[6], sd->scsi3addr[7]);
1171                 }
1172                 datalen = buflen - offset;
1173                 if (datalen < 0) {      /* they're reading past EOF. */
1174                         datalen = 0;
1175                         *start = buffer+buflen; 
1176                 } else
1177                         *start = buffer + offset;
1178                 return(datalen);
1179         } else  /* User is writing to /proc/scsi/cciss*?/?*  ... */
1180                 return cciss_scsi_user_command(cntl_num, sh->host_no,
1181                         buffer, length);        
1182
1183
1184 /* cciss_scatter_gather takes a struct scsi_cmnd, (cmd), and does the pci 
1185    dma mapping  and fills in the scatter gather entries of the 
1186    cciss command, cp. */
1187
1188 static void
1189 cciss_scatter_gather(struct pci_dev *pdev, 
1190                 CommandList_struct *cp, 
1191                 struct scsi_cmnd *cmd)
1192 {
1193         unsigned int len;
1194         struct scatterlist *sg;
1195         __u64 addr64;
1196         int use_sg, i;
1197
1198         BUG_ON(scsi_sg_count(cmd) > MAXSGENTRIES);
1199
1200         use_sg = scsi_dma_map(cmd);
1201         if (use_sg) {   /* not too many addrs? */
1202                 scsi_for_each_sg(cmd, sg, use_sg, i) {
1203                         addr64 = (__u64) sg_dma_address(sg);
1204                         len  = sg_dma_len(sg);
1205                         cp->SG[i].Addr.lower =
1206                                 (__u32) (addr64 & (__u64) 0x00000000FFFFFFFF);
1207                         cp->SG[i].Addr.upper =
1208                                 (__u32) ((addr64 >> 32) & (__u64) 0x00000000FFFFFFFF);
1209                         cp->SG[i].Len = len;
1210                         cp->SG[i].Ext = 0;  // we are not chaining
1211                 }
1212         }
1213
1214         cp->Header.SGList = (__u8) use_sg;   /* no. SGs contig in this cmd */
1215         cp->Header.SGTotal = (__u16) use_sg; /* total sgs in this cmd list */
1216         return;
1217 }
1218
1219
1220 static int
1221 cciss_scsi_queue_command (struct scsi_cmnd *cmd, void (* done)(struct scsi_cmnd *))
1222 {
1223         ctlr_info_t **c;
1224         int ctlr, rc;
1225         unsigned char scsi3addr[8];
1226         CommandList_struct *cp;
1227         unsigned long flags;
1228
1229         // Get the ptr to our adapter structure (hba[i]) out of cmd->host.
1230         // We violate cmd->host privacy here.  (Is there another way?)
1231         c = (ctlr_info_t **) &cmd->device->host->hostdata[0];   
1232         ctlr = (*c)->ctlr;
1233
1234         rc = lookup_scsi3addr(ctlr, cmd->device->channel, cmd->device->id, 
1235                         cmd->device->lun, scsi3addr);
1236         if (rc != 0) {
1237                 /* the scsi nexus does not match any that we presented... */
1238                 /* pretend to mid layer that we got selection timeout */
1239                 cmd->result = DID_NO_CONNECT << 16;
1240                 done(cmd);
1241                 /* we might want to think about registering controller itself
1242                    as a processor device on the bus so sg binds to it. */
1243                 return 0;
1244         }
1245
1246         /* printk("cciss_queue_command, p=%p, cmd=0x%02x, c%db%dt%dl%d\n", 
1247                 cmd, cmd->cmnd[0], ctlr, cmd->channel, cmd->target, cmd->lun);*/
1248         // printk("q:%p:c%db%dt%dl%d ", cmd, ctlr, cmd->channel, 
1249         //      cmd->target, cmd->lun);
1250
1251         /* Ok, we have a reasonable scsi nexus, so send the cmd down, and
1252            see what the device thinks of it. */
1253
1254         spin_lock_irqsave(CCISS_LOCK(ctlr), flags);
1255         cp = scsi_cmd_alloc(*c);
1256         spin_unlock_irqrestore(CCISS_LOCK(ctlr), flags);
1257         if (cp == NULL) {                       /* trouble... */
1258                 printk("scsi_cmd_alloc returned NULL!\n");
1259                 /* FIXME: next 3 lines are -> BAD! <- */
1260                 cmd->result = DID_NO_CONNECT << 16;
1261                 done(cmd);
1262                 return 0;
1263         }
1264
1265         // Fill in the command list header
1266
1267         cmd->scsi_done = done;    // save this for use by completion code 
1268
1269         // save cp in case we have to abort it 
1270         cmd->host_scribble = (unsigned char *) cp; 
1271
1272         cp->cmd_type = CMD_SCSI;
1273         cp->scsi_cmd = cmd;
1274         cp->Header.ReplyQueue = 0;  // unused in simple mode
1275         memcpy(&cp->Header.LUN.LunAddrBytes[0], &scsi3addr[0], 8);
1276         cp->Header.Tag.lower = cp->busaddr;  // Use k. address of cmd as tag
1277         
1278         // Fill in the request block...
1279
1280         cp->Request.Timeout = 0;
1281         memset(cp->Request.CDB, 0, sizeof(cp->Request.CDB));
1282         BUG_ON(cmd->cmd_len > sizeof(cp->Request.CDB));
1283         cp->Request.CDBLen = cmd->cmd_len;
1284         memcpy(cp->Request.CDB, cmd->cmnd, cmd->cmd_len);
1285         cp->Request.Type.Type = TYPE_CMD;
1286         cp->Request.Type.Attribute = ATTR_SIMPLE;
1287         switch(cmd->sc_data_direction)
1288         {
1289           case DMA_TO_DEVICE: cp->Request.Type.Direction = XFER_WRITE; break;
1290           case DMA_FROM_DEVICE: cp->Request.Type.Direction = XFER_READ; break;
1291           case DMA_NONE: cp->Request.Type.Direction = XFER_NONE; break;
1292           case DMA_BIDIRECTIONAL:
1293                 // This can happen if a buggy application does a scsi passthru
1294                 // and sets both inlen and outlen to non-zero. ( see
1295                 // ../scsi/scsi_ioctl.c:scsi_ioctl_send_command() )
1296
1297                 cp->Request.Type.Direction = XFER_RSVD;
1298                 // This is technically wrong, and cciss controllers should
1299                 // reject it with CMD_INVALID, which is the most correct 
1300                 // response, but non-fibre backends appear to let it 
1301                 // slide by, and give the same results as if this field
1302                 // were set correctly.  Either way is acceptable for
1303                 // our purposes here.
1304
1305                 break;
1306
1307           default: 
1308                 printk("cciss: unknown data direction: %d\n", 
1309                         cmd->sc_data_direction);
1310                 BUG();
1311                 break;
1312         }
1313
1314         cciss_scatter_gather((*c)->pdev, cp, cmd); // Fill the SG list
1315
1316         /* Put the request on the tail of the request queue */
1317
1318         spin_lock_irqsave(CCISS_LOCK(ctlr), flags);
1319         addQ(&(*c)->reqQ, cp);
1320         (*c)->Qdepth++;
1321         start_io(*c);
1322         spin_unlock_irqrestore(CCISS_LOCK(ctlr), flags);
1323
1324         /* the cmd'll come back via intr handler in complete_scsi_command()  */
1325         return 0;
1326 }
1327
1328 static void 
1329 cciss_unregister_scsi(int ctlr)
1330 {
1331         struct cciss_scsi_adapter_data_t *sa;
1332         struct cciss_scsi_cmd_stack_t *stk;
1333         unsigned long flags;
1334
1335         /* we are being forcibly unloaded, and may not refuse. */
1336
1337         spin_lock_irqsave(CCISS_LOCK(ctlr), flags);
1338         sa = (struct cciss_scsi_adapter_data_t *) hba[ctlr]->scsi_ctlr;
1339         stk = &sa->cmd_stack; 
1340
1341         /* if we weren't ever actually registered, don't unregister */ 
1342         if (sa->registered) {
1343                 spin_unlock_irqrestore(CCISS_LOCK(ctlr), flags);
1344                 scsi_remove_host(sa->scsi_host);
1345                 scsi_host_put(sa->scsi_host);
1346                 spin_lock_irqsave(CCISS_LOCK(ctlr), flags);
1347         }
1348
1349         /* set scsi_host to NULL so our detect routine will 
1350            find us on register */
1351         sa->scsi_host = NULL;
1352         spin_unlock_irqrestore(CCISS_LOCK(ctlr), flags);
1353         scsi_cmd_stack_free(ctlr);
1354         kfree(sa);
1355 }
1356
1357 static int 
1358 cciss_register_scsi(int ctlr)
1359 {
1360         unsigned long flags;
1361
1362         CPQ_TAPE_LOCK(ctlr, flags);
1363
1364         /* Since this is really a block driver, the SCSI core may not be 
1365            initialized at init time, in which case, calling scsi_register_host
1366            would hang.  Instead, we do it later, via /proc filesystem
1367            and rc scripts, when we know SCSI core is good to go. */
1368
1369         /* Only register if SCSI devices are detected. */
1370         if (ccissscsi[ctlr].ndevices != 0) {
1371                 ((struct cciss_scsi_adapter_data_t *) 
1372                         hba[ctlr]->scsi_ctlr)->registered = 1;
1373                 CPQ_TAPE_UNLOCK(ctlr, flags);
1374                 return cciss_scsi_detect(ctlr);
1375         }
1376         CPQ_TAPE_UNLOCK(ctlr, flags);
1377         printk(KERN_INFO 
1378                 "cciss%d: No appropriate SCSI device detected, "
1379                 "SCSI subsystem not engaged.\n", ctlr);
1380         return 0;
1381 }
1382
1383 static int 
1384 cciss_engage_scsi(int ctlr)
1385 {
1386         struct cciss_scsi_adapter_data_t *sa;
1387         struct cciss_scsi_cmd_stack_t *stk;
1388         unsigned long flags;
1389
1390         spin_lock_irqsave(CCISS_LOCK(ctlr), flags);
1391         sa = (struct cciss_scsi_adapter_data_t *) hba[ctlr]->scsi_ctlr;
1392         stk = &sa->cmd_stack; 
1393
1394         if (((struct cciss_scsi_adapter_data_t *) 
1395                 hba[ctlr]->scsi_ctlr)->registered) {
1396                 printk("cciss%d: SCSI subsystem already engaged.\n", ctlr);
1397                 spin_unlock_irqrestore(CCISS_LOCK(ctlr), flags);
1398                 return ENXIO;
1399         }
1400         spin_unlock_irqrestore(CCISS_LOCK(ctlr), flags);
1401         cciss_update_non_disk_devices(ctlr, -1);
1402         cciss_register_scsi(ctlr);
1403         return 0;
1404 }
1405
1406 static void
1407 cciss_seq_tape_report(struct seq_file *seq, int ctlr)
1408 {
1409         unsigned long flags;
1410
1411         CPQ_TAPE_LOCK(ctlr, flags);
1412         seq_printf(seq,
1413                 "Sequential access devices: %d\n\n",
1414                         ccissscsi[ctlr].ndevices);
1415         CPQ_TAPE_UNLOCK(ctlr, flags);
1416 }
1417
1418
1419 /* Need at least one of these error handlers to keep ../scsi/hosts.c from 
1420  * complaining.  Doing a host- or bus-reset can't do anything good here. 
1421  * Despite what it might say in scsi_error.c, there may well be commands
1422  * on the controller, as the cciss driver registers twice, once as a block
1423  * device for the logical drives, and once as a scsi device, for any tape
1424  * drives.  So we know there are no commands out on the tape drives, but we
1425  * don't know there are no commands on the controller, and it is likely 
1426  * that there probably are, as the cciss block device is most commonly used
1427  * as a boot device (embedded controller on HP/Compaq systems.)
1428 */
1429
1430 static int cciss_eh_device_reset_handler(struct scsi_cmnd *scsicmd)
1431 {
1432         int rc;
1433         CommandList_struct *cmd_in_trouble;
1434         ctlr_info_t **c;
1435         int ctlr;
1436
1437         /* find the controller to which the command to be aborted was sent */
1438         c = (ctlr_info_t **) &scsicmd->device->host->hostdata[0];       
1439         if (c == NULL) /* paranoia */
1440                 return FAILED;
1441         ctlr = (*c)->ctlr;
1442         printk(KERN_WARNING "cciss%d: resetting tape drive or medium changer.\n", ctlr);
1443
1444         /* find the command that's giving us trouble */
1445         cmd_in_trouble = (CommandList_struct *) scsicmd->host_scribble;
1446         if (cmd_in_trouble == NULL) { /* paranoia */
1447                 return FAILED;
1448         }
1449         /* send a reset to the SCSI LUN which the command was sent to */
1450         rc = sendcmd(CCISS_RESET_MSG, ctlr, NULL, 0, 2, 0, 0, 
1451                 (unsigned char *) &cmd_in_trouble->Header.LUN.LunAddrBytes[0], 
1452                 TYPE_MSG);
1453         /* sendcmd turned off interrupts on the board, turn 'em back on. */
1454         (*c)->access.set_intr_mask(*c, CCISS_INTR_ON);
1455         if (rc == 0)
1456                 return SUCCESS;
1457         printk(KERN_WARNING "cciss%d: resetting device failed.\n", ctlr);
1458         return FAILED;
1459 }
1460
1461 static int  cciss_eh_abort_handler(struct scsi_cmnd *scsicmd)
1462 {
1463         int rc;
1464         CommandList_struct *cmd_to_abort;
1465         ctlr_info_t **c;
1466         int ctlr;
1467
1468         /* find the controller to which the command to be aborted was sent */
1469         c = (ctlr_info_t **) &scsicmd->device->host->hostdata[0];       
1470         if (c == NULL) /* paranoia */
1471                 return FAILED;
1472         ctlr = (*c)->ctlr;
1473         printk(KERN_WARNING "cciss%d: aborting tardy SCSI cmd\n", ctlr);
1474
1475         /* find the command to be aborted */
1476         cmd_to_abort = (CommandList_struct *) scsicmd->host_scribble;
1477         if (cmd_to_abort == NULL) /* paranoia */
1478                 return FAILED;
1479         rc = sendcmd(CCISS_ABORT_MSG, ctlr, &cmd_to_abort->Header.Tag, 
1480                 0, 2, 0, 0, 
1481                 (unsigned char *) &cmd_to_abort->Header.LUN.LunAddrBytes[0], 
1482                 TYPE_MSG);
1483         /* sendcmd turned off interrupts on the board, turn 'em back on. */
1484         (*c)->access.set_intr_mask(*c, CCISS_INTR_ON);
1485         if (rc == 0)
1486                 return SUCCESS;
1487         return FAILED;
1488
1489 }
1490
1491 #else /* no CONFIG_CISS_SCSI_TAPE */
1492
1493 /* If no tape support, then these become defined out of existence */
1494
1495 #define cciss_scsi_setup(cntl_num)
1496 #define cciss_unregister_scsi(ctlr)
1497 #define cciss_register_scsi(ctlr)
1498
1499 #endif /* CONFIG_CISS_SCSI_TAPE */