xref: /linux/drivers/scsi/scsi_debug.c (revision d8327c784b51b57dac2c26cfad87dce0d68dfd98)
1 /*
2  *  linux/kernel/scsi_debug.c
3  * vvvvvvvvvvvvvvvvvvvvvvv Original vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
4  *  Copyright (C) 1992  Eric Youngdale
5  *  Simulate a host adapter with 2 disks attached.  Do a lot of checking
6  *  to make sure that we are not getting blocks mixed up, and PANIC if
7  *  anything out of the ordinary is seen.
8  * ^^^^^^^^^^^^^^^^^^^^^^^ Original ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
9  *
10  *  This version is more generic, simulating a variable number of disk
11  *  (or disk like devices) sharing a common amount of RAM
12  *
13  *
14  *  For documentation see http://www.torque.net/sg/sdebug26.html
15  *
16  *   D. Gilbert (dpg) work for Magneto-Optical device test [20010421]
17  *   dpg: work for devfs large number of disks [20010809]
18  *        forked for lk 2.5 series [20011216, 20020101]
19  *        use vmalloc() more inquiry+mode_sense [20020302]
20  *        add timers for delayed responses [20020721]
21  *   Patrick Mansfield <patmans@us.ibm.com> max_luns+scsi_level [20021031]
22  *   Mike Anderson <andmike@us.ibm.com> sysfs work [20021118]
23  *   dpg: change style of boot options to "scsi_debug.num_tgts=2" and
24  *        module options to "modprobe scsi_debug num_tgts=2" [20021221]
25  */
26 
27 #include <linux/config.h>
28 #include <linux/module.h>
29 
30 #include <linux/kernel.h>
31 #include <linux/sched.h>
32 #include <linux/errno.h>
33 #include <linux/timer.h>
34 #include <linux/types.h>
35 #include <linux/string.h>
36 #include <linux/genhd.h>
37 #include <linux/fs.h>
38 #include <linux/init.h>
39 #include <linux/proc_fs.h>
40 #include <linux/smp_lock.h>
41 #include <linux/vmalloc.h>
42 #include <linux/moduleparam.h>
43 
44 #include <linux/blkdev.h>
45 #include "scsi.h"
46 #include <scsi/scsi_host.h>
47 #include <scsi/scsicam.h>
48 
49 #include <linux/stat.h>
50 
51 #include "scsi_logging.h"
52 #include "scsi_debug.h"
53 
54 #define SCSI_DEBUG_VERSION "1.75"
55 static const char * scsi_debug_version_date = "20050113";
56 
57 /* Additional Sense Code (ASC) used */
58 #define NO_ADDED_SENSE 0x0
59 #define UNRECOVERED_READ_ERR 0x11
60 #define INVALID_OPCODE 0x20
61 #define ADDR_OUT_OF_RANGE 0x21
62 #define INVALID_FIELD_IN_CDB 0x24
63 #define POWERON_RESET 0x29
64 #define SAVING_PARAMS_UNSUP 0x39
65 #define THRESHHOLD_EXCEEDED 0x5d
66 
67 #define SDEBUG_TAGGED_QUEUING 0 /* 0 | MSG_SIMPLE_TAG | MSG_ORDERED_TAG */
68 
69 /* Default values for driver parameters */
70 #define DEF_NUM_HOST   1
71 #define DEF_NUM_TGTS   1
72 #define DEF_MAX_LUNS   1
73 /* With these defaults, this driver will make 1 host with 1 target
74  * (id 0) containing 1 logical unit (lun 0). That is 1 device.
75  */
76 #define DEF_DELAY   1
77 #define DEF_DEV_SIZE_MB   8
78 #define DEF_EVERY_NTH   0
79 #define DEF_NUM_PARTS   0
80 #define DEF_OPTS   0
81 #define DEF_SCSI_LEVEL   5    /* INQUIRY, byte2 [5->SPC-3] */
82 #define DEF_PTYPE   0
83 #define DEF_D_SENSE   0
84 
85 /* bit mask values for scsi_debug_opts */
86 #define SCSI_DEBUG_OPT_NOISE   1
87 #define SCSI_DEBUG_OPT_MEDIUM_ERR   2
88 #define SCSI_DEBUG_OPT_TIMEOUT   4
89 #define SCSI_DEBUG_OPT_RECOVERED_ERR   8
90 /* When "every_nth" > 0 then modulo "every_nth" commands:
91  *   - a no response is simulated if SCSI_DEBUG_OPT_TIMEOUT is set
92  *   - a RECOVERED_ERROR is simulated on successful read and write
93  *     commands if SCSI_DEBUG_OPT_RECOVERED_ERR is set.
94  *
95  * When "every_nth" < 0 then after "- every_nth" commands:
96  *   - a no response is simulated if SCSI_DEBUG_OPT_TIMEOUT is set
97  *   - a RECOVERED_ERROR is simulated on successful read and write
98  *     commands if SCSI_DEBUG_OPT_RECOVERED_ERR is set.
99  * This will continue until some other action occurs (e.g. the user
100  * writing a new value (other than -1 or 1) to every_nth via sysfs).
101  */
102 
103 /* when 1==SCSI_DEBUG_OPT_MEDIUM_ERR, a medium error is simulated at this
104  * sector on read commands: */
105 #define OPT_MEDIUM_ERR_ADDR   0x1234 /* that's sector 4660 in decimal */
106 
107 /* If REPORT LUNS has luns >= 256 it can choose "flat space" (value 1)
108  * or "peripheral device" addressing (value 0) */
109 #define SAM2_LUN_ADDRESS_METHOD 0
110 
111 static int scsi_debug_add_host = DEF_NUM_HOST;
112 static int scsi_debug_delay = DEF_DELAY;
113 static int scsi_debug_dev_size_mb = DEF_DEV_SIZE_MB;
114 static int scsi_debug_every_nth = DEF_EVERY_NTH;
115 static int scsi_debug_max_luns = DEF_MAX_LUNS;
116 static int scsi_debug_num_parts = DEF_NUM_PARTS;
117 static int scsi_debug_num_tgts = DEF_NUM_TGTS; /* targets per host */
118 static int scsi_debug_opts = DEF_OPTS;
119 static int scsi_debug_scsi_level = DEF_SCSI_LEVEL;
120 static int scsi_debug_ptype = DEF_PTYPE; /* SCSI peripheral type (0==disk) */
121 static int scsi_debug_dsense = DEF_D_SENSE;
122 
123 static int scsi_debug_cmnd_count = 0;
124 
125 #define DEV_READONLY(TGT)      (0)
126 #define DEV_REMOVEABLE(TGT)    (0)
127 
128 static unsigned long sdebug_store_size;	/* in bytes */
129 static sector_t sdebug_capacity;	/* in sectors */
130 
131 /* old BIOS stuff, kernel may get rid of them but some mode sense pages
132    may still need them */
133 static int sdebug_heads;		/* heads per disk */
134 static int sdebug_cylinders_per;	/* cylinders per surface */
135 static int sdebug_sectors_per;		/* sectors per cylinder */
136 
137 /* default sector size is 512 bytes, 2**9 bytes */
138 #define POW2_SECT_SIZE 9
139 #define SECT_SIZE (1 << POW2_SECT_SIZE)
140 #define SECT_SIZE_PER(TGT) SECT_SIZE
141 
142 #define SDEBUG_MAX_PARTS 4
143 
144 #define SDEBUG_SENSE_LEN 32
145 
146 struct sdebug_dev_info {
147 	struct list_head dev_list;
148 	unsigned char sense_buff[SDEBUG_SENSE_LEN];	/* weak nexus */
149 	unsigned int channel;
150 	unsigned int target;
151 	unsigned int lun;
152 	struct sdebug_host_info *sdbg_host;
153 	char reset;
154 	char used;
155 };
156 
157 struct sdebug_host_info {
158 	struct list_head host_list;
159 	struct Scsi_Host *shost;
160 	struct device dev;
161 	struct list_head dev_info_list;
162 };
163 
164 #define to_sdebug_host(d)	\
165 	container_of(d, struct sdebug_host_info, dev)
166 
167 static LIST_HEAD(sdebug_host_list);
168 static DEFINE_SPINLOCK(sdebug_host_list_lock);
169 
170 typedef void (* done_funct_t) (struct scsi_cmnd *);
171 
172 struct sdebug_queued_cmd {
173 	int in_use;
174 	struct timer_list cmnd_timer;
175 	done_funct_t done_funct;
176 	struct scsi_cmnd * a_cmnd;
177 	int scsi_result;
178 };
179 static struct sdebug_queued_cmd queued_arr[SCSI_DEBUG_CANQUEUE];
180 
181 static struct scsi_host_template sdebug_driver_template = {
182 	.proc_info =		scsi_debug_proc_info,
183 	.name =			"SCSI DEBUG",
184 	.info =			scsi_debug_info,
185 	.slave_alloc =		scsi_debug_slave_alloc,
186 	.slave_configure =	scsi_debug_slave_configure,
187 	.slave_destroy =	scsi_debug_slave_destroy,
188 	.ioctl =		scsi_debug_ioctl,
189 	.queuecommand =		scsi_debug_queuecommand,
190 	.eh_abort_handler =	scsi_debug_abort,
191 	.eh_bus_reset_handler = scsi_debug_bus_reset,
192 	.eh_device_reset_handler = scsi_debug_device_reset,
193 	.eh_host_reset_handler = scsi_debug_host_reset,
194 	.bios_param =		scsi_debug_biosparam,
195 	.can_queue =		SCSI_DEBUG_CANQUEUE,
196 	.this_id =		7,
197 	.sg_tablesize =		64,
198 	.cmd_per_lun =		3,
199 	.max_sectors =		4096,
200 	.unchecked_isa_dma = 	0,
201 	.use_clustering = 	DISABLE_CLUSTERING,
202 	.module =		THIS_MODULE,
203 };
204 
205 static unsigned char * fake_storep;	/* ramdisk storage */
206 
207 static int num_aborts = 0;
208 static int num_dev_resets = 0;
209 static int num_bus_resets = 0;
210 static int num_host_resets = 0;
211 
212 static DEFINE_SPINLOCK(queued_arr_lock);
213 static DEFINE_RWLOCK(atomic_rw);
214 
215 static char sdebug_proc_name[] = "scsi_debug";
216 
217 static int sdebug_driver_probe(struct device *);
218 static int sdebug_driver_remove(struct device *);
219 static struct bus_type pseudo_lld_bus;
220 
221 static struct device_driver sdebug_driverfs_driver = {
222 	.name 		= sdebug_proc_name,
223 	.bus		= &pseudo_lld_bus,
224 };
225 
226 static const int check_condition_result =
227 		(DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
228 
229 /* function declarations */
230 static int resp_inquiry(struct scsi_cmnd * SCpnt, int target,
231 			struct sdebug_dev_info * devip);
232 static int resp_requests(struct scsi_cmnd * SCpnt,
233 			 struct sdebug_dev_info * devip);
234 static int resp_readcap(struct scsi_cmnd * SCpnt,
235 			struct sdebug_dev_info * devip);
236 static int resp_mode_sense(struct scsi_cmnd * SCpnt, int target,
237 			   struct sdebug_dev_info * devip);
238 static int resp_read(struct scsi_cmnd * SCpnt, int upper_blk, int block,
239 		     int num, struct sdebug_dev_info * devip);
240 static int resp_write(struct scsi_cmnd * SCpnt, int upper_blk, int block,
241 		      int num, struct sdebug_dev_info * devip);
242 static int resp_report_luns(struct scsi_cmnd * SCpnt,
243 			    struct sdebug_dev_info * devip);
244 static int fill_from_dev_buffer(struct scsi_cmnd * scp, unsigned char * arr,
245                                 int arr_len);
246 static int fetch_to_dev_buffer(struct scsi_cmnd * scp, unsigned char * arr,
247                                int max_arr_len);
248 static void timer_intr_handler(unsigned long);
249 static struct sdebug_dev_info * devInfoReg(struct scsi_device * sdev);
250 static void mk_sense_buffer(struct sdebug_dev_info * devip, int key,
251 			    int asc, int asq);
252 static int check_reset(struct scsi_cmnd * SCpnt,
253 		       struct sdebug_dev_info * devip);
254 static int schedule_resp(struct scsi_cmnd * cmnd,
255 			 struct sdebug_dev_info * devip,
256 			 done_funct_t done, int scsi_result, int delta_jiff);
257 static void __init sdebug_build_parts(unsigned char * ramp);
258 static void __init init_all_queued(void);
259 static void stop_all_queued(void);
260 static int stop_queued_cmnd(struct scsi_cmnd * cmnd);
261 static int inquiry_evpd_83(unsigned char * arr, int dev_id_num,
262                            const char * dev_id_str, int dev_id_str_len);
263 static void do_create_driverfs_files(void);
264 static void do_remove_driverfs_files(void);
265 
266 static int sdebug_add_adapter(void);
267 static void sdebug_remove_adapter(void);
268 static void sdebug_max_tgts_luns(void);
269 
270 static struct device pseudo_primary;
271 static struct bus_type pseudo_lld_bus;
272 
273 
274 static
275 int scsi_debug_queuecommand(struct scsi_cmnd * SCpnt, done_funct_t done)
276 {
277 	unsigned char *cmd = (unsigned char *) SCpnt->cmnd;
278 	int block, upper_blk, num, k;
279 	int errsts = 0;
280 	int target = scmd_id(SCpnt);
281 	struct sdebug_dev_info * devip = NULL;
282 	int inj_recovered = 0;
283 
284 	if (done == NULL)
285 		return 0;	/* assume mid level reprocessing command */
286 
287 	if ((SCSI_DEBUG_OPT_NOISE & scsi_debug_opts) && cmd) {
288 		printk(KERN_INFO "scsi_debug: cmd ");
289 		for (k = 0, num = SCpnt->cmd_len; k < num; ++k)
290 			printk("%02x ", (int)cmd[k]);
291 		printk("\n");
292 	}
293         if(target == sdebug_driver_template.this_id) {
294 		printk(KERN_INFO "scsi_debug: initiator's id used as "
295 		       "target!\n");
296 		return schedule_resp(SCpnt, NULL, done,
297 				     DID_NO_CONNECT << 16, 0);
298         }
299 
300 	if (SCpnt->device->lun >= scsi_debug_max_luns)
301 		return schedule_resp(SCpnt, NULL, done,
302 				     DID_NO_CONNECT << 16, 0);
303 	devip = devInfoReg(SCpnt->device);
304 	if (NULL == devip)
305 		return schedule_resp(SCpnt, NULL, done,
306 				     DID_NO_CONNECT << 16, 0);
307 
308         if ((scsi_debug_every_nth != 0) &&
309             (++scsi_debug_cmnd_count >= abs(scsi_debug_every_nth))) {
310                 scsi_debug_cmnd_count = 0;
311 		if (scsi_debug_every_nth < -1)
312 			scsi_debug_every_nth = -1;
313 		if (SCSI_DEBUG_OPT_TIMEOUT & scsi_debug_opts)
314 			return 0; /* ignore command causing timeout */
315 		else if (SCSI_DEBUG_OPT_RECOVERED_ERR & scsi_debug_opts)
316 			inj_recovered = 1; /* to reads and writes below */
317         }
318 
319 	switch (*cmd) {
320 	case INQUIRY:     /* mandatory, ignore unit attention */
321 		errsts = resp_inquiry(SCpnt, target, devip);
322 		break;
323 	case REQUEST_SENSE:	/* mandatory, ignore unit attention */
324 		errsts = resp_requests(SCpnt, devip);
325 		break;
326 	case REZERO_UNIT:	/* actually this is REWIND for SSC */
327 	case START_STOP:
328 		errsts = check_reset(SCpnt, devip);
329 		break;
330 	case ALLOW_MEDIUM_REMOVAL:
331 		if ((errsts = check_reset(SCpnt, devip)))
332 			break;
333 		if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
334 			printk(KERN_INFO "scsi_debug: Medium removal %s\n",
335 			        cmd[4] ? "inhibited" : "enabled");
336 		break;
337 	case SEND_DIAGNOSTIC:     /* mandatory */
338 		errsts = check_reset(SCpnt, devip);
339 		break;
340 	case TEST_UNIT_READY:     /* mandatory */
341 		errsts = check_reset(SCpnt, devip);
342 		break;
343         case RESERVE:
344 		errsts = check_reset(SCpnt, devip);
345                 break;
346         case RESERVE_10:
347 		errsts = check_reset(SCpnt, devip);
348                 break;
349         case RELEASE:
350 		errsts = check_reset(SCpnt, devip);
351                 break;
352         case RELEASE_10:
353 		errsts = check_reset(SCpnt, devip);
354                 break;
355 	case READ_CAPACITY:
356 		errsts = resp_readcap(SCpnt, devip);
357 		break;
358 	case READ_16:
359 	case READ_12:
360 	case READ_10:
361 	case READ_6:
362 		if ((errsts = check_reset(SCpnt, devip)))
363 			break;
364 		upper_blk = 0;
365 		if ((*cmd) == READ_16) {
366 			upper_blk = cmd[5] + (cmd[4] << 8) +
367 				    (cmd[3] << 16) + (cmd[2] << 24);
368 			block = cmd[9] + (cmd[8] << 8) +
369 				(cmd[7] << 16) + (cmd[6] << 24);
370 			num = cmd[13] + (cmd[12] << 8) +
371 				(cmd[11] << 16) + (cmd[10] << 24);
372 		} else if ((*cmd) == READ_12) {
373 			block = cmd[5] + (cmd[4] << 8) +
374 				(cmd[3] << 16) + (cmd[2] << 24);
375 			num = cmd[9] + (cmd[8] << 8) +
376 				(cmd[7] << 16) + (cmd[6] << 24);
377 		} else if ((*cmd) == READ_10) {
378 			block = cmd[5] + (cmd[4] << 8) +
379 				(cmd[3] << 16) + (cmd[2] << 24);
380 			num = cmd[8] + (cmd[7] << 8);
381 		} else {
382 			block = cmd[3] + (cmd[2] << 8) +
383 				((cmd[1] & 0x1f) << 16);
384 			num = cmd[4];
385 		}
386 		errsts = resp_read(SCpnt, upper_blk, block, num, devip);
387 		if (inj_recovered && (0 == errsts)) {
388 			mk_sense_buffer(devip, RECOVERED_ERROR,
389 					THRESHHOLD_EXCEEDED, 0);
390 			errsts = check_condition_result;
391 		}
392 		break;
393 	case REPORT_LUNS:	/* mandatory, ignore unit attention */
394 		errsts = resp_report_luns(SCpnt, devip);
395 		break;
396 	case VERIFY:		/* 10 byte SBC-2 command */
397 		errsts = check_reset(SCpnt, devip);
398 		break;
399 	case WRITE_16:
400 	case WRITE_12:
401 	case WRITE_10:
402 	case WRITE_6:
403 		if ((errsts = check_reset(SCpnt, devip)))
404 			break;
405 		upper_blk = 0;
406 		if ((*cmd) == WRITE_16) {
407 			upper_blk = cmd[5] + (cmd[4] << 8) +
408 				    (cmd[3] << 16) + (cmd[2] << 24);
409 			block = cmd[9] + (cmd[8] << 8) +
410 				(cmd[7] << 16) + (cmd[6] << 24);
411 			num = cmd[13] + (cmd[12] << 8) +
412 				(cmd[11] << 16) + (cmd[10] << 24);
413 		} else if ((*cmd) == WRITE_12) {
414 			block = cmd[5] + (cmd[4] << 8) +
415 				(cmd[3] << 16) + (cmd[2] << 24);
416 			num = cmd[9] + (cmd[8] << 8) +
417 				(cmd[7] << 16) + (cmd[6] << 24);
418 		} else if ((*cmd) == WRITE_10) {
419 			block = cmd[5] + (cmd[4] << 8) +
420 				(cmd[3] << 16) + (cmd[2] << 24);
421 			num = cmd[8] + (cmd[7] << 8);
422 		} else {
423 			block = cmd[3] + (cmd[2] << 8) +
424 				((cmd[1] & 0x1f) << 16);
425 			num = cmd[4];
426 		}
427 		errsts = resp_write(SCpnt, upper_blk, block, num, devip);
428 		if (inj_recovered && (0 == errsts)) {
429 			mk_sense_buffer(devip, RECOVERED_ERROR,
430 					THRESHHOLD_EXCEEDED, 0);
431 			errsts = check_condition_result;
432 		}
433 		break;
434 	case MODE_SENSE:
435 	case MODE_SENSE_10:
436 		errsts = resp_mode_sense(SCpnt, target, devip);
437 		break;
438 	case SYNCHRONIZE_CACHE:
439 		errsts = check_reset(SCpnt, devip);
440 		break;
441 	default:
442 		if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
443 			printk(KERN_INFO "scsi_debug: Opcode: 0x%x not "
444 			       "supported\n", *cmd);
445 		if ((errsts = check_reset(SCpnt, devip)))
446 			break;	/* Unit attention takes precedence */
447 		mk_sense_buffer(devip, ILLEGAL_REQUEST, INVALID_OPCODE, 0);
448 		errsts = check_condition_result;
449 		break;
450 	}
451 	return schedule_resp(SCpnt, devip, done, errsts, scsi_debug_delay);
452 }
453 
454 static int scsi_debug_ioctl(struct scsi_device *dev, int cmd, void __user *arg)
455 {
456 	if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts) {
457 		printk(KERN_INFO "scsi_debug: ioctl: cmd=0x%x\n", cmd);
458 	}
459 	return -EINVAL;
460 	/* return -ENOTTY; // correct return but upsets fdisk */
461 }
462 
463 static int check_reset(struct scsi_cmnd * SCpnt, struct sdebug_dev_info * devip)
464 {
465 	if (devip->reset) {
466 		if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
467 			printk(KERN_INFO "scsi_debug: Reporting Unit "
468 			       "attention: power on reset\n");
469 		devip->reset = 0;
470 		mk_sense_buffer(devip, UNIT_ATTENTION, POWERON_RESET, 0);
471 		return check_condition_result;
472 	}
473 	return 0;
474 }
475 
476 /* Returns 0 if ok else (DID_ERROR << 16). Sets scp->resid . */
477 static int fill_from_dev_buffer(struct scsi_cmnd * scp, unsigned char * arr,
478 				int arr_len)
479 {
480 	int k, req_len, act_len, len, active;
481 	void * kaddr;
482 	void * kaddr_off;
483 	struct scatterlist * sgpnt;
484 
485 	if (0 == scp->request_bufflen)
486 		return 0;
487 	if (NULL == scp->request_buffer)
488 		return (DID_ERROR << 16);
489 	if (! ((scp->sc_data_direction == DMA_BIDIRECTIONAL) ||
490 	      (scp->sc_data_direction == DMA_FROM_DEVICE)))
491 		return (DID_ERROR << 16);
492 	if (0 == scp->use_sg) {
493 		req_len = scp->request_bufflen;
494 		act_len = (req_len < arr_len) ? req_len : arr_len;
495 		memcpy(scp->request_buffer, arr, act_len);
496 		scp->resid = req_len - act_len;
497 		return 0;
498 	}
499 	sgpnt = (struct scatterlist *)scp->request_buffer;
500 	active = 1;
501 	for (k = 0, req_len = 0, act_len = 0; k < scp->use_sg; ++k, ++sgpnt) {
502 		if (active) {
503 			kaddr = (unsigned char *)
504 				kmap_atomic(sgpnt->page, KM_USER0);
505 			if (NULL == kaddr)
506 				return (DID_ERROR << 16);
507 			kaddr_off = (unsigned char *)kaddr + sgpnt->offset;
508 			len = sgpnt->length;
509 			if ((req_len + len) > arr_len) {
510 				active = 0;
511 				len = arr_len - req_len;
512 			}
513 			memcpy(kaddr_off, arr + req_len, len);
514 			kunmap_atomic(kaddr, KM_USER0);
515 			act_len += len;
516 		}
517 		req_len += sgpnt->length;
518 	}
519 	scp->resid = req_len - act_len;
520 	return 0;
521 }
522 
523 /* Returns number of bytes fetched into 'arr' or -1 if error. */
524 static int fetch_to_dev_buffer(struct scsi_cmnd * scp, unsigned char * arr,
525 			       int max_arr_len)
526 {
527 	int k, req_len, len, fin;
528 	void * kaddr;
529 	void * kaddr_off;
530 	struct scatterlist * sgpnt;
531 
532 	if (0 == scp->request_bufflen)
533 		return 0;
534 	if (NULL == scp->request_buffer)
535 		return -1;
536 	if (! ((scp->sc_data_direction == DMA_BIDIRECTIONAL) ||
537 	      (scp->sc_data_direction == DMA_TO_DEVICE)))
538 		return -1;
539 	if (0 == scp->use_sg) {
540 		req_len = scp->request_bufflen;
541 		len = (req_len < max_arr_len) ? req_len : max_arr_len;
542 		memcpy(arr, scp->request_buffer, len);
543 		return len;
544 	}
545 	sgpnt = (struct scatterlist *)scp->request_buffer;
546 	for (k = 0, req_len = 0, fin = 0; k < scp->use_sg; ++k, ++sgpnt) {
547 		kaddr = (unsigned char *)kmap_atomic(sgpnt->page, KM_USER0);
548 		if (NULL == kaddr)
549 			return -1;
550 		kaddr_off = (unsigned char *)kaddr + sgpnt->offset;
551 		len = sgpnt->length;
552 		if ((req_len + len) > max_arr_len) {
553 			len = max_arr_len - req_len;
554 			fin = 1;
555 		}
556 		memcpy(arr + req_len, kaddr_off, len);
557 		kunmap_atomic(kaddr, KM_USER0);
558 		if (fin)
559 			return req_len + len;
560 		req_len += sgpnt->length;
561 	}
562 	return req_len;
563 }
564 
565 
566 static const char * inq_vendor_id = "Linux   ";
567 static const char * inq_product_id = "scsi_debug      ";
568 static const char * inq_product_rev = "0004";
569 
570 static int inquiry_evpd_83(unsigned char * arr, int dev_id_num,
571 			   const char * dev_id_str, int dev_id_str_len)
572 {
573 	int num;
574 
575 	/* Two identification descriptors: */
576 	/* T10 vendor identifier field format (faked) */
577 	arr[0] = 0x2;	/* ASCII */
578 	arr[1] = 0x1;
579 	arr[2] = 0x0;
580 	memcpy(&arr[4], inq_vendor_id, 8);
581 	memcpy(&arr[12], inq_product_id, 16);
582 	memcpy(&arr[28], dev_id_str, dev_id_str_len);
583 	num = 8 + 16 + dev_id_str_len;
584 	arr[3] = num;
585 	num += 4;
586 	/* NAA IEEE registered identifier (faked) */
587 	arr[num] = 0x1;	/* binary */
588 	arr[num + 1] = 0x3;
589 	arr[num + 2] = 0x0;
590 	arr[num + 3] = 0x8;
591 	arr[num + 4] = 0x51;	/* ieee company id=0x123456 (faked) */
592 	arr[num + 5] = 0x23;
593 	arr[num + 6] = 0x45;
594 	arr[num + 7] = 0x60;
595 	arr[num + 8] = (dev_id_num >> 24);
596 	arr[num + 9] = (dev_id_num >> 16) & 0xff;
597 	arr[num + 10] = (dev_id_num >> 8) & 0xff;
598 	arr[num + 11] = dev_id_num & 0xff;
599 	return num + 12;
600 }
601 
602 
603 #define SDEBUG_LONG_INQ_SZ 96
604 #define SDEBUG_MAX_INQ_ARR_SZ 128
605 
606 static int resp_inquiry(struct scsi_cmnd * scp, int target,
607 			struct sdebug_dev_info * devip)
608 {
609 	unsigned char pq_pdt;
610 	unsigned char arr[SDEBUG_MAX_INQ_ARR_SZ];
611 	unsigned char *cmd = (unsigned char *)scp->cmnd;
612 	int alloc_len;
613 
614 	alloc_len = (cmd[3] << 8) + cmd[4];
615 	memset(arr, 0, SDEBUG_MAX_INQ_ARR_SZ);
616 	pq_pdt = (scsi_debug_ptype & 0x1f);
617 	arr[0] = pq_pdt;
618 	if (0x2 & cmd[1]) {  /* CMDDT bit set */
619 		mk_sense_buffer(devip, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB,
620 			       	0);
621 		return check_condition_result;
622 	} else if (0x1 & cmd[1]) {  /* EVPD bit set */
623 		int dev_id_num, len;
624 		char dev_id_str[6];
625 
626 		dev_id_num = ((devip->sdbg_host->shost->host_no + 1) * 2000) +
627 			     (devip->target * 1000) + devip->lun;
628 		len = scnprintf(dev_id_str, 6, "%d", dev_id_num);
629 		if (0 == cmd[2]) { /* supported vital product data pages */
630 			arr[3] = 3;
631 			arr[4] = 0x0; /* this page */
632 			arr[5] = 0x80; /* unit serial number */
633 			arr[6] = 0x83; /* device identification */
634 		} else if (0x80 == cmd[2]) { /* unit serial number */
635 			arr[1] = 0x80;
636 			arr[3] = len;
637 			memcpy(&arr[4], dev_id_str, len);
638 		} else if (0x83 == cmd[2]) { /* device identification */
639 			arr[1] = 0x83;
640 			arr[3] = inquiry_evpd_83(&arr[4], dev_id_num,
641 						 dev_id_str, len);
642 		} else {
643 			/* Illegal request, invalid field in cdb */
644 			mk_sense_buffer(devip, ILLEGAL_REQUEST,
645 					INVALID_FIELD_IN_CDB, 0);
646 			return check_condition_result;
647 		}
648 		return fill_from_dev_buffer(scp, arr,
649 			    min(alloc_len, SDEBUG_MAX_INQ_ARR_SZ));
650 	}
651 	/* drops through here for a standard inquiry */
652 	arr[1] = DEV_REMOVEABLE(target) ? 0x80 : 0;	/* Removable disk */
653 	arr[2] = scsi_debug_scsi_level;
654 	arr[3] = 2;    /* response_data_format==2 */
655 	arr[4] = SDEBUG_LONG_INQ_SZ - 5;
656 	arr[6] = 0x1; /* claim: ADDR16 */
657 	/* arr[6] |= 0x40; ... claim: EncServ (enclosure services) */
658 	arr[7] = 0x3a; /* claim: WBUS16, SYNC, LINKED + CMDQUE */
659 	memcpy(&arr[8], inq_vendor_id, 8);
660 	memcpy(&arr[16], inq_product_id, 16);
661 	memcpy(&arr[32], inq_product_rev, 4);
662 	/* version descriptors (2 bytes each) follow */
663 	arr[58] = 0x0; arr[59] = 0x40; /* SAM-2 */
664 	arr[60] = 0x3; arr[61] = 0x0;  /* SPC-3 */
665 	if (scsi_debug_ptype == 0) {
666 		arr[62] = 0x1; arr[63] = 0x80; /* SBC */
667 	} else if (scsi_debug_ptype == 1) {
668 		arr[62] = 0x2; arr[63] = 0x00; /* SSC */
669 	}
670 	return fill_from_dev_buffer(scp, arr,
671 			    min(alloc_len, SDEBUG_LONG_INQ_SZ));
672 }
673 
674 static int resp_requests(struct scsi_cmnd * scp,
675 			 struct sdebug_dev_info * devip)
676 {
677 	unsigned char * sbuff;
678 	unsigned char *cmd = (unsigned char *)scp->cmnd;
679 	unsigned char arr[SDEBUG_SENSE_LEN];
680 	int len = 18;
681 
682 	memset(arr, 0, SDEBUG_SENSE_LEN);
683 	if (devip->reset == 1)
684 		mk_sense_buffer(devip, 0, NO_ADDED_SENSE, 0);
685 	sbuff = devip->sense_buff;
686 	if ((cmd[1] & 1) && (! scsi_debug_dsense)) {
687 		/* DESC bit set and sense_buff in fixed format */
688 		arr[0] = 0x72;
689 		arr[1] = sbuff[2];     /* sense key */
690 		arr[2] = sbuff[12];    /* asc */
691 		arr[3] = sbuff[13];    /* ascq */
692 		len = 8;
693 	} else
694 		memcpy(arr, sbuff, SDEBUG_SENSE_LEN);
695 	mk_sense_buffer(devip, 0, NO_ADDED_SENSE, 0);
696 	return fill_from_dev_buffer(scp, arr, len);
697 }
698 
699 #define SDEBUG_READCAP_ARR_SZ 8
700 static int resp_readcap(struct scsi_cmnd * scp,
701 			struct sdebug_dev_info * devip)
702 {
703 	unsigned char arr[SDEBUG_READCAP_ARR_SZ];
704 	unsigned long capac;
705 	int errsts;
706 
707 	if ((errsts = check_reset(scp, devip)))
708 		return errsts;
709 	memset(arr, 0, SDEBUG_READCAP_ARR_SZ);
710 	capac = (unsigned long)sdebug_capacity - 1;
711 	arr[0] = (capac >> 24);
712 	arr[1] = (capac >> 16) & 0xff;
713 	arr[2] = (capac >> 8) & 0xff;
714 	arr[3] = capac & 0xff;
715 	arr[6] = (SECT_SIZE_PER(target) >> 8) & 0xff;
716 	arr[7] = SECT_SIZE_PER(target) & 0xff;
717 	return fill_from_dev_buffer(scp, arr, SDEBUG_READCAP_ARR_SZ);
718 }
719 
720 /* <<Following mode page info copied from ST318451LW>> */
721 
722 static int resp_err_recov_pg(unsigned char * p, int pcontrol, int target)
723 {	/* Read-Write Error Recovery page for mode_sense */
724 	unsigned char err_recov_pg[] = {0x1, 0xa, 0xc0, 11, 240, 0, 0, 0,
725 					5, 0, 0xff, 0xff};
726 
727 	memcpy(p, err_recov_pg, sizeof(err_recov_pg));
728 	if (1 == pcontrol)
729 		memset(p + 2, 0, sizeof(err_recov_pg) - 2);
730 	return sizeof(err_recov_pg);
731 }
732 
733 static int resp_disconnect_pg(unsigned char * p, int pcontrol, int target)
734 { 	/* Disconnect-Reconnect page for mode_sense */
735 	unsigned char disconnect_pg[] = {0x2, 0xe, 128, 128, 0, 10, 0, 0,
736 					 0, 0, 0, 0, 0, 0, 0, 0};
737 
738 	memcpy(p, disconnect_pg, sizeof(disconnect_pg));
739 	if (1 == pcontrol)
740 		memset(p + 2, 0, sizeof(disconnect_pg) - 2);
741 	return sizeof(disconnect_pg);
742 }
743 
744 static int resp_format_pg(unsigned char * p, int pcontrol, int target)
745 {       /* Format device page for mode_sense */
746         unsigned char format_pg[] = {0x3, 0x16, 0, 0, 0, 0, 0, 0,
747                                      0, 0, 0, 0, 0, 0, 0, 0,
748                                      0, 0, 0, 0, 0x40, 0, 0, 0};
749 
750         memcpy(p, format_pg, sizeof(format_pg));
751         p[10] = (sdebug_sectors_per >> 8) & 0xff;
752         p[11] = sdebug_sectors_per & 0xff;
753         p[12] = (SECT_SIZE >> 8) & 0xff;
754         p[13] = SECT_SIZE & 0xff;
755         if (DEV_REMOVEABLE(target))
756                 p[20] |= 0x20; /* should agree with INQUIRY */
757         if (1 == pcontrol)
758                 memset(p + 2, 0, sizeof(format_pg) - 2);
759         return sizeof(format_pg);
760 }
761 
762 static int resp_caching_pg(unsigned char * p, int pcontrol, int target)
763 { 	/* Caching page for mode_sense */
764 	unsigned char caching_pg[] = {0x8, 18, 0x14, 0, 0xff, 0xff, 0, 0,
765 		0xff, 0xff, 0xff, 0xff, 0x80, 0x14, 0, 0,     0, 0, 0, 0};
766 
767 	memcpy(p, caching_pg, sizeof(caching_pg));
768 	if (1 == pcontrol)
769 		memset(p + 2, 0, sizeof(caching_pg) - 2);
770 	return sizeof(caching_pg);
771 }
772 
773 static int resp_ctrl_m_pg(unsigned char * p, int pcontrol, int target)
774 { 	/* Control mode page for mode_sense */
775 	unsigned char ctrl_m_pg[] = {0xa, 10, 2, 0, 0, 0, 0, 0,
776 				     0, 0, 0x2, 0x4b};
777 
778 	if (scsi_debug_dsense)
779 		ctrl_m_pg[2] |= 0x4;
780 	memcpy(p, ctrl_m_pg, sizeof(ctrl_m_pg));
781 	if (1 == pcontrol)
782 		memset(p + 2, 0, sizeof(ctrl_m_pg) - 2);
783 	return sizeof(ctrl_m_pg);
784 }
785 
786 static int resp_iec_m_pg(unsigned char * p, int pcontrol, int target)
787 {	/* Informational Exceptions control mode page for mode_sense */
788 	unsigned char iec_m_pg[] = {0x1c, 0xa, 0x08, 0, 0, 0, 0, 0,
789 				    0, 0, 0x0, 0x0};
790 	memcpy(p, iec_m_pg, sizeof(iec_m_pg));
791 	if (1 == pcontrol)
792 		memset(p + 2, 0, sizeof(iec_m_pg) - 2);
793 	return sizeof(iec_m_pg);
794 }
795 
796 #define SDEBUG_MAX_MSENSE_SZ 256
797 
798 static int resp_mode_sense(struct scsi_cmnd * scp, int target,
799 			   struct sdebug_dev_info * devip)
800 {
801 	unsigned char dbd;
802 	int pcontrol, pcode, subpcode;
803 	unsigned char dev_spec;
804 	int alloc_len, msense_6, offset, len, errsts;
805 	unsigned char * ap;
806 	unsigned char arr[SDEBUG_MAX_MSENSE_SZ];
807 	unsigned char *cmd = (unsigned char *)scp->cmnd;
808 
809 	if ((errsts = check_reset(scp, devip)))
810 		return errsts;
811 	dbd = cmd[1] & 0x8;
812 	pcontrol = (cmd[2] & 0xc0) >> 6;
813 	pcode = cmd[2] & 0x3f;
814 	subpcode = cmd[3];
815 	msense_6 = (MODE_SENSE == cmd[0]);
816 	alloc_len = msense_6 ? cmd[4] : ((cmd[7] << 8) | cmd[8]);
817 	memset(arr, 0, SDEBUG_MAX_MSENSE_SZ);
818 	if (0x3 == pcontrol) {  /* Saving values not supported */
819 		mk_sense_buffer(devip, ILLEGAL_REQUEST, SAVING_PARAMS_UNSUP,
820 			       	0);
821 		return check_condition_result;
822 	}
823 	dev_spec = DEV_READONLY(target) ? 0x80 : 0x0;
824 	if (msense_6) {
825 		arr[2] = dev_spec;
826 		offset = 4;
827 	} else {
828 		arr[3] = dev_spec;
829 		offset = 8;
830 	}
831 	ap = arr + offset;
832 
833 	if (0 != subpcode) { /* TODO: Control Extension page */
834 		mk_sense_buffer(devip, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB,
835 			       	0);
836 		return check_condition_result;
837 	}
838 	switch (pcode) {
839 	case 0x1:	/* Read-Write error recovery page, direct access */
840 		len = resp_err_recov_pg(ap, pcontrol, target);
841 		offset += len;
842 		break;
843 	case 0x2:	/* Disconnect-Reconnect page, all devices */
844 		len = resp_disconnect_pg(ap, pcontrol, target);
845 		offset += len;
846 		break;
847         case 0x3:       /* Format device page, direct access */
848                 len = resp_format_pg(ap, pcontrol, target);
849                 offset += len;
850                 break;
851 	case 0x8:	/* Caching page, direct access */
852 		len = resp_caching_pg(ap, pcontrol, target);
853 		offset += len;
854 		break;
855 	case 0xa:	/* Control Mode page, all devices */
856 		len = resp_ctrl_m_pg(ap, pcontrol, target);
857 		offset += len;
858 		break;
859 	case 0x1c:	/* Informational Exceptions Mode page, all devices */
860 		len = resp_iec_m_pg(ap, pcontrol, target);
861 		offset += len;
862 		break;
863 	case 0x3f:	/* Read all Mode pages */
864 		len = resp_err_recov_pg(ap, pcontrol, target);
865 		len += resp_disconnect_pg(ap + len, pcontrol, target);
866 		len += resp_format_pg(ap + len, pcontrol, target);
867 		len += resp_caching_pg(ap + len, pcontrol, target);
868 		len += resp_ctrl_m_pg(ap + len, pcontrol, target);
869 		len += resp_iec_m_pg(ap + len, pcontrol, target);
870 		offset += len;
871 		break;
872 	default:
873 		mk_sense_buffer(devip, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB,
874 			       	0);
875 		return check_condition_result;
876 	}
877 	if (msense_6)
878 		arr[0] = offset - 1;
879 	else {
880 		arr[0] = ((offset - 2) >> 8) & 0xff;
881 		arr[1] = (offset - 2) & 0xff;
882 	}
883 	return fill_from_dev_buffer(scp, arr, min(alloc_len, offset));
884 }
885 
886 static int resp_read(struct scsi_cmnd * SCpnt, int upper_blk, int block,
887 		     int num, struct sdebug_dev_info * devip)
888 {
889 	unsigned long iflags;
890 	int ret;
891 
892 	if (upper_blk || (block + num > sdebug_capacity)) {
893 		mk_sense_buffer(devip, ILLEGAL_REQUEST, ADDR_OUT_OF_RANGE,
894 				0);
895 		return check_condition_result;
896 	}
897 	if ((SCSI_DEBUG_OPT_MEDIUM_ERR & scsi_debug_opts) &&
898 	    (block <= OPT_MEDIUM_ERR_ADDR) &&
899 	    ((block + num) > OPT_MEDIUM_ERR_ADDR)) {
900 		mk_sense_buffer(devip, MEDIUM_ERROR, UNRECOVERED_READ_ERR,
901 				0);
902 		/* claim unrecoverable read error */
903 		return check_condition_result;
904 	}
905 	read_lock_irqsave(&atomic_rw, iflags);
906 	ret = fill_from_dev_buffer(SCpnt, fake_storep + (block * SECT_SIZE),
907 			   	   num * SECT_SIZE);
908 	read_unlock_irqrestore(&atomic_rw, iflags);
909 	return ret;
910 }
911 
912 static int resp_write(struct scsi_cmnd * SCpnt, int upper_blk, int block,
913 		      int num, struct sdebug_dev_info * devip)
914 {
915 	unsigned long iflags;
916 	int res;
917 
918 	if (upper_blk || (block + num > sdebug_capacity)) {
919 		mk_sense_buffer(devip, ILLEGAL_REQUEST, ADDR_OUT_OF_RANGE,
920 			       	0);
921 		return check_condition_result;
922 	}
923 
924 	write_lock_irqsave(&atomic_rw, iflags);
925 	res = fetch_to_dev_buffer(SCpnt, fake_storep + (block * SECT_SIZE),
926 			   	  num * SECT_SIZE);
927 	write_unlock_irqrestore(&atomic_rw, iflags);
928 	if (-1 == res)
929 		return (DID_ERROR << 16);
930 	else if ((res < (num * SECT_SIZE)) &&
931 		 (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts))
932 		printk(KERN_INFO "scsi_debug: write: cdb indicated=%d, "
933 		       " IO sent=%d bytes\n", num * SECT_SIZE, res);
934 	return 0;
935 }
936 
937 #define SDEBUG_RLUN_ARR_SZ 128
938 
939 static int resp_report_luns(struct scsi_cmnd * scp,
940 			    struct sdebug_dev_info * devip)
941 {
942 	unsigned int alloc_len;
943 	int lun_cnt, i, upper;
944 	unsigned char *cmd = (unsigned char *)scp->cmnd;
945 	int select_report = (int)cmd[2];
946 	struct scsi_lun *one_lun;
947 	unsigned char arr[SDEBUG_RLUN_ARR_SZ];
948 
949 	alloc_len = cmd[9] + (cmd[8] << 8) + (cmd[7] << 16) + (cmd[6] << 24);
950 	if ((alloc_len < 16) || (select_report > 2)) {
951 		mk_sense_buffer(devip, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB,
952 			       	0);
953 		return check_condition_result;
954 	}
955 	/* can produce response with up to 16k luns (lun 0 to lun 16383) */
956 	memset(arr, 0, SDEBUG_RLUN_ARR_SZ);
957 	lun_cnt = scsi_debug_max_luns;
958 	arr[2] = ((sizeof(struct scsi_lun) * lun_cnt) >> 8) & 0xff;
959 	arr[3] = (sizeof(struct scsi_lun) * lun_cnt) & 0xff;
960 	lun_cnt = min((int)((SDEBUG_RLUN_ARR_SZ - 8) /
961 			    sizeof(struct scsi_lun)), lun_cnt);
962 	one_lun = (struct scsi_lun *) &arr[8];
963 	for (i = 0; i < lun_cnt; i++) {
964 		upper = (i >> 8) & 0x3f;
965 		if (upper)
966 			one_lun[i].scsi_lun[0] =
967 			    (upper | (SAM2_LUN_ADDRESS_METHOD << 6));
968 		one_lun[i].scsi_lun[1] = i & 0xff;
969 	}
970 	return fill_from_dev_buffer(scp, arr,
971 				    min((int)alloc_len, SDEBUG_RLUN_ARR_SZ));
972 }
973 
974 /* When timer goes off this function is called. */
975 static void timer_intr_handler(unsigned long indx)
976 {
977 	struct sdebug_queued_cmd * sqcp;
978 	unsigned long iflags;
979 
980 	if (indx >= SCSI_DEBUG_CANQUEUE) {
981 		printk(KERN_ERR "scsi_debug:timer_intr_handler: indx too "
982 		       "large\n");
983 		return;
984 	}
985 	spin_lock_irqsave(&queued_arr_lock, iflags);
986 	sqcp = &queued_arr[(int)indx];
987 	if (! sqcp->in_use) {
988 		printk(KERN_ERR "scsi_debug:timer_intr_handler: Unexpected "
989 		       "interrupt\n");
990 		spin_unlock_irqrestore(&queued_arr_lock, iflags);
991 		return;
992 	}
993 	sqcp->in_use = 0;
994 	if (sqcp->done_funct) {
995 		sqcp->a_cmnd->result = sqcp->scsi_result;
996 		sqcp->done_funct(sqcp->a_cmnd); /* callback to mid level */
997 	}
998 	sqcp->done_funct = NULL;
999 	spin_unlock_irqrestore(&queued_arr_lock, iflags);
1000 }
1001 
1002 static int scsi_debug_slave_alloc(struct scsi_device * sdp)
1003 {
1004 	if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
1005 		sdev_printk(KERN_INFO, sdp, "scsi_debug: slave_alloc\n");
1006 	return 0;
1007 }
1008 
1009 static int scsi_debug_slave_configure(struct scsi_device * sdp)
1010 {
1011 	struct sdebug_dev_info * devip;
1012 
1013 	if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
1014 		sdev_printk(KERN_INFO, sdp, "scsi_debug: slave_configure\n");
1015 	if (sdp->host->max_cmd_len != SCSI_DEBUG_MAX_CMD_LEN)
1016 		sdp->host->max_cmd_len = SCSI_DEBUG_MAX_CMD_LEN;
1017 	devip = devInfoReg(sdp);
1018 	sdp->hostdata = devip;
1019 	if (sdp->host->cmd_per_lun)
1020 		scsi_adjust_queue_depth(sdp, SDEBUG_TAGGED_QUEUING,
1021 					sdp->host->cmd_per_lun);
1022 	return 0;
1023 }
1024 
1025 static void scsi_debug_slave_destroy(struct scsi_device * sdp)
1026 {
1027 	struct sdebug_dev_info * devip =
1028 				(struct sdebug_dev_info *)sdp->hostdata;
1029 
1030 	if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
1031 		sdev_printk(KERN_INFO, sdp, "scsi_debug: slave_destroy\n");
1032 	if (devip) {
1033 		/* make this slot avaliable for re-use */
1034 		devip->used = 0;
1035 		sdp->hostdata = NULL;
1036 	}
1037 }
1038 
1039 static struct sdebug_dev_info * devInfoReg(struct scsi_device * sdev)
1040 {
1041 	struct sdebug_host_info * sdbg_host;
1042 	struct sdebug_dev_info * open_devip = NULL;
1043 	struct sdebug_dev_info * devip =
1044 			(struct sdebug_dev_info *)sdev->hostdata;
1045 
1046 	if (devip)
1047 		return devip;
1048 	sdbg_host = *(struct sdebug_host_info **) sdev->host->hostdata;
1049         if(! sdbg_host) {
1050                 printk(KERN_ERR "Host info NULL\n");
1051 		return NULL;
1052         }
1053 	list_for_each_entry(devip, &sdbg_host->dev_info_list, dev_list) {
1054 		if ((devip->used) && (devip->channel == sdev->channel) &&
1055                     (devip->target == sdev->id) &&
1056                     (devip->lun == sdev->lun))
1057                         return devip;
1058 		else {
1059 			if ((!devip->used) && (!open_devip))
1060 				open_devip = devip;
1061 		}
1062 	}
1063 	if (NULL == open_devip) { /* try and make a new one */
1064 		open_devip = kmalloc(sizeof(*open_devip),GFP_KERNEL);
1065 		if (NULL == open_devip) {
1066 			printk(KERN_ERR "%s: out of memory at line %d\n",
1067 				__FUNCTION__, __LINE__);
1068 			return NULL;
1069 		}
1070 		memset(open_devip, 0, sizeof(*open_devip));
1071 		open_devip->sdbg_host = sdbg_host;
1072 		list_add_tail(&open_devip->dev_list,
1073 		&sdbg_host->dev_info_list);
1074 	}
1075         if (open_devip) {
1076 		open_devip->channel = sdev->channel;
1077 		open_devip->target = sdev->id;
1078 		open_devip->lun = sdev->lun;
1079 		open_devip->sdbg_host = sdbg_host;
1080 		open_devip->reset = 1;
1081 		open_devip->used = 1;
1082 		memset(open_devip->sense_buff, 0, SDEBUG_SENSE_LEN);
1083 		if (scsi_debug_dsense)
1084 			open_devip->sense_buff[0] = 0x72;
1085 		else {
1086 			open_devip->sense_buff[0] = 0x70;
1087 			open_devip->sense_buff[7] = 0xa;
1088 		}
1089 		return open_devip;
1090         }
1091         return NULL;
1092 }
1093 
1094 static void mk_sense_buffer(struct sdebug_dev_info * devip, int key,
1095 			    int asc, int asq)
1096 {
1097 	unsigned char * sbuff;
1098 
1099 	sbuff = devip->sense_buff;
1100 	memset(sbuff, 0, SDEBUG_SENSE_LEN);
1101 	if (scsi_debug_dsense) {
1102 		sbuff[0] = 0x72;  /* descriptor, current */
1103 		sbuff[1] = key;
1104 		sbuff[2] = asc;
1105 		sbuff[3] = asq;
1106 	} else {
1107 		sbuff[0] = 0x70;  /* fixed, current */
1108 		sbuff[2] = key;
1109 		sbuff[7] = 0xa;	  /* implies 18 byte sense buffer */
1110 		sbuff[12] = asc;
1111 		sbuff[13] = asq;
1112 	}
1113 	if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
1114 		printk(KERN_INFO "scsi_debug:    [sense_key,asc,ascq]: "
1115 		      "[0x%x,0x%x,0x%x]\n", key, asc, asq);
1116 }
1117 
1118 static int scsi_debug_abort(struct scsi_cmnd * SCpnt)
1119 {
1120 	if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
1121 		printk(KERN_INFO "scsi_debug: abort\n");
1122 	++num_aborts;
1123 	stop_queued_cmnd(SCpnt);
1124 	return SUCCESS;
1125 }
1126 
1127 static int scsi_debug_biosparam(struct scsi_device *sdev,
1128 		struct block_device * bdev, sector_t capacity, int *info)
1129 {
1130 	int res;
1131 	unsigned char *buf;
1132 
1133 	if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
1134 		printk(KERN_INFO "scsi_debug: biosparam\n");
1135 	buf = scsi_bios_ptable(bdev);
1136 	if (buf) {
1137 		res = scsi_partsize(buf, capacity,
1138 				    &info[2], &info[0], &info[1]);
1139 		kfree(buf);
1140 		if (! res)
1141 			return res;
1142 	}
1143 	info[0] = sdebug_heads;
1144 	info[1] = sdebug_sectors_per;
1145 	info[2] = sdebug_cylinders_per;
1146 	return 0;
1147 }
1148 
1149 static int scsi_debug_device_reset(struct scsi_cmnd * SCpnt)
1150 {
1151 	struct sdebug_dev_info * devip;
1152 
1153 	if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
1154 		printk(KERN_INFO "scsi_debug: device_reset\n");
1155 	++num_dev_resets;
1156 	if (SCpnt) {
1157 		devip = devInfoReg(SCpnt->device);
1158 		if (devip)
1159 			devip->reset = 1;
1160 	}
1161 	return SUCCESS;
1162 }
1163 
1164 static int scsi_debug_bus_reset(struct scsi_cmnd * SCpnt)
1165 {
1166 	struct sdebug_host_info *sdbg_host;
1167         struct sdebug_dev_info * dev_info;
1168         struct scsi_device * sdp;
1169         struct Scsi_Host * hp;
1170 
1171 	if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
1172 		printk(KERN_INFO "scsi_debug: bus_reset\n");
1173 	++num_bus_resets;
1174 	if (SCpnt && ((sdp = SCpnt->device)) && ((hp = sdp->host))) {
1175 		sdbg_host = *(struct sdebug_host_info **) hp->hostdata;
1176 		if (sdbg_host) {
1177 			list_for_each_entry(dev_info,
1178                                             &sdbg_host->dev_info_list,
1179                                             dev_list)
1180 				dev_info->reset = 1;
1181 		}
1182 	}
1183 	return SUCCESS;
1184 }
1185 
1186 static int scsi_debug_host_reset(struct scsi_cmnd * SCpnt)
1187 {
1188 	struct sdebug_host_info * sdbg_host;
1189         struct sdebug_dev_info * dev_info;
1190 
1191 	if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
1192 		printk(KERN_INFO "scsi_debug: host_reset\n");
1193 	++num_host_resets;
1194         spin_lock(&sdebug_host_list_lock);
1195         list_for_each_entry(sdbg_host, &sdebug_host_list, host_list) {
1196                 list_for_each_entry(dev_info, &sdbg_host->dev_info_list,
1197                                     dev_list)
1198                         dev_info->reset = 1;
1199         }
1200         spin_unlock(&sdebug_host_list_lock);
1201 	stop_all_queued();
1202 	return SUCCESS;
1203 }
1204 
1205 /* Returns 1 if found 'cmnd' and deleted its timer. else returns 0 */
1206 static int stop_queued_cmnd(struct scsi_cmnd * cmnd)
1207 {
1208 	unsigned long iflags;
1209 	int k;
1210 	struct sdebug_queued_cmd * sqcp;
1211 
1212 	spin_lock_irqsave(&queued_arr_lock, iflags);
1213 	for (k = 0; k < SCSI_DEBUG_CANQUEUE; ++k) {
1214 		sqcp = &queued_arr[k];
1215 		if (sqcp->in_use && (cmnd == sqcp->a_cmnd)) {
1216 			del_timer_sync(&sqcp->cmnd_timer);
1217 			sqcp->in_use = 0;
1218 			sqcp->a_cmnd = NULL;
1219 			break;
1220 		}
1221 	}
1222 	spin_unlock_irqrestore(&queued_arr_lock, iflags);
1223 	return (k < SCSI_DEBUG_CANQUEUE) ? 1 : 0;
1224 }
1225 
1226 /* Deletes (stops) timers of all queued commands */
1227 static void stop_all_queued(void)
1228 {
1229 	unsigned long iflags;
1230 	int k;
1231 	struct sdebug_queued_cmd * sqcp;
1232 
1233 	spin_lock_irqsave(&queued_arr_lock, iflags);
1234 	for (k = 0; k < SCSI_DEBUG_CANQUEUE; ++k) {
1235 		sqcp = &queued_arr[k];
1236 		if (sqcp->in_use && sqcp->a_cmnd) {
1237 			del_timer_sync(&sqcp->cmnd_timer);
1238 			sqcp->in_use = 0;
1239 			sqcp->a_cmnd = NULL;
1240 		}
1241 	}
1242 	spin_unlock_irqrestore(&queued_arr_lock, iflags);
1243 }
1244 
1245 /* Initializes timers in queued array */
1246 static void __init init_all_queued(void)
1247 {
1248 	unsigned long iflags;
1249 	int k;
1250 	struct sdebug_queued_cmd * sqcp;
1251 
1252 	spin_lock_irqsave(&queued_arr_lock, iflags);
1253 	for (k = 0; k < SCSI_DEBUG_CANQUEUE; ++k) {
1254 		sqcp = &queued_arr[k];
1255 		init_timer(&sqcp->cmnd_timer);
1256 		sqcp->in_use = 0;
1257 		sqcp->a_cmnd = NULL;
1258 	}
1259 	spin_unlock_irqrestore(&queued_arr_lock, iflags);
1260 }
1261 
1262 static void __init sdebug_build_parts(unsigned char * ramp)
1263 {
1264 	struct partition * pp;
1265 	int starts[SDEBUG_MAX_PARTS + 2];
1266 	int sectors_per_part, num_sectors, k;
1267 	int heads_by_sects, start_sec, end_sec;
1268 
1269 	/* assume partition table already zeroed */
1270 	if ((scsi_debug_num_parts < 1) || (sdebug_store_size < 1048576))
1271 		return;
1272 	if (scsi_debug_num_parts > SDEBUG_MAX_PARTS) {
1273 		scsi_debug_num_parts = SDEBUG_MAX_PARTS;
1274 		printk(KERN_WARNING "scsi_debug:build_parts: reducing "
1275 				    "partitions to %d\n", SDEBUG_MAX_PARTS);
1276 	}
1277 	num_sectors = (int)(sdebug_store_size / SECT_SIZE);
1278 	sectors_per_part = (num_sectors - sdebug_sectors_per)
1279 			   / scsi_debug_num_parts;
1280 	heads_by_sects = sdebug_heads * sdebug_sectors_per;
1281         starts[0] = sdebug_sectors_per;
1282 	for (k = 1; k < scsi_debug_num_parts; ++k)
1283 		starts[k] = ((k * sectors_per_part) / heads_by_sects)
1284 			    * heads_by_sects;
1285 	starts[scsi_debug_num_parts] = num_sectors;
1286 	starts[scsi_debug_num_parts + 1] = 0;
1287 
1288 	ramp[510] = 0x55;	/* magic partition markings */
1289 	ramp[511] = 0xAA;
1290 	pp = (struct partition *)(ramp + 0x1be);
1291 	for (k = 0; starts[k + 1]; ++k, ++pp) {
1292 		start_sec = starts[k];
1293 		end_sec = starts[k + 1] - 1;
1294 		pp->boot_ind = 0;
1295 
1296 		pp->cyl = start_sec / heads_by_sects;
1297 		pp->head = (start_sec - (pp->cyl * heads_by_sects))
1298 			   / sdebug_sectors_per;
1299 		pp->sector = (start_sec % sdebug_sectors_per) + 1;
1300 
1301 		pp->end_cyl = end_sec / heads_by_sects;
1302 		pp->end_head = (end_sec - (pp->end_cyl * heads_by_sects))
1303 			       / sdebug_sectors_per;
1304 		pp->end_sector = (end_sec % sdebug_sectors_per) + 1;
1305 
1306 		pp->start_sect = start_sec;
1307 		pp->nr_sects = end_sec - start_sec + 1;
1308 		pp->sys_ind = 0x83;	/* plain Linux partition */
1309 	}
1310 }
1311 
1312 static int schedule_resp(struct scsi_cmnd * cmnd,
1313 			 struct sdebug_dev_info * devip,
1314 			 done_funct_t done, int scsi_result, int delta_jiff)
1315 {
1316 	if ((SCSI_DEBUG_OPT_NOISE & scsi_debug_opts) && cmnd) {
1317 		if (scsi_result) {
1318 			struct scsi_device * sdp = cmnd->device;
1319 
1320 			sdev_printk(KERN_INFO, sdp,
1321 				"non-zero result=0x%x\n",
1322 			       	scsi_result);
1323 		}
1324 	}
1325 	if (cmnd && devip) {
1326 		/* simulate autosense by this driver */
1327 		if (SAM_STAT_CHECK_CONDITION == (scsi_result & 0xff))
1328 			memcpy(cmnd->sense_buffer, devip->sense_buff,
1329 			       (SCSI_SENSE_BUFFERSIZE > SDEBUG_SENSE_LEN) ?
1330 			       SDEBUG_SENSE_LEN : SCSI_SENSE_BUFFERSIZE);
1331 	}
1332 	if (delta_jiff <= 0) {
1333 		if (cmnd)
1334 			cmnd->result = scsi_result;
1335 		if (done)
1336 			done(cmnd);
1337 		return 0;
1338 	} else {
1339 		unsigned long iflags;
1340 		int k;
1341 		struct sdebug_queued_cmd * sqcp = NULL;
1342 
1343 		spin_lock_irqsave(&queued_arr_lock, iflags);
1344 		for (k = 0; k < SCSI_DEBUG_CANQUEUE; ++k) {
1345 			sqcp = &queued_arr[k];
1346 			if (! sqcp->in_use)
1347 				break;
1348 		}
1349 		if (k >= SCSI_DEBUG_CANQUEUE) {
1350 			spin_unlock_irqrestore(&queued_arr_lock, iflags);
1351 			printk(KERN_WARNING "scsi_debug: can_queue exceeded\n");
1352 			return 1;	/* report busy to mid level */
1353 		}
1354 		sqcp->in_use = 1;
1355 		sqcp->a_cmnd = cmnd;
1356 		sqcp->scsi_result = scsi_result;
1357 		sqcp->done_funct = done;
1358 		sqcp->cmnd_timer.function = timer_intr_handler;
1359 		sqcp->cmnd_timer.data = k;
1360 		sqcp->cmnd_timer.expires = jiffies + delta_jiff;
1361 		add_timer(&sqcp->cmnd_timer);
1362 		spin_unlock_irqrestore(&queued_arr_lock, iflags);
1363 		if (cmnd)
1364 			cmnd->result = 0;
1365 		return 0;
1366 	}
1367 }
1368 
1369 /* Set 'perm' (4th argument) to 0 to disable module_param's definition
1370  * of sysfs parameters (which module_param doesn't yet support).
1371  * Sysfs parameters defined explicitly below.
1372  */
1373 module_param_named(add_host, scsi_debug_add_host, int, 0); /* perm=0644 */
1374 module_param_named(delay, scsi_debug_delay, int, 0); /* perm=0644 */
1375 module_param_named(dev_size_mb, scsi_debug_dev_size_mb, int, 0);
1376 module_param_named(dsense, scsi_debug_dsense, int, 0);
1377 module_param_named(every_nth, scsi_debug_every_nth, int, 0);
1378 module_param_named(max_luns, scsi_debug_max_luns, int, 0);
1379 module_param_named(num_parts, scsi_debug_num_parts, int, 0);
1380 module_param_named(num_tgts, scsi_debug_num_tgts, int, 0);
1381 module_param_named(opts, scsi_debug_opts, int, 0); /* perm=0644 */
1382 module_param_named(ptype, scsi_debug_ptype, int, 0);
1383 module_param_named(scsi_level, scsi_debug_scsi_level, int, 0);
1384 
1385 MODULE_AUTHOR("Eric Youngdale + Douglas Gilbert");
1386 MODULE_DESCRIPTION("SCSI debug adapter driver");
1387 MODULE_LICENSE("GPL");
1388 MODULE_VERSION(SCSI_DEBUG_VERSION);
1389 
1390 MODULE_PARM_DESC(add_host, "0..127 hosts allowed(def=1)");
1391 MODULE_PARM_DESC(delay, "# of jiffies to delay response(def=1)");
1392 MODULE_PARM_DESC(dev_size_mb, "size in MB of ram shared by devs");
1393 MODULE_PARM_DESC(dsense, "use descriptor sense format(def: fixed)");
1394 MODULE_PARM_DESC(every_nth, "timeout every nth command(def=100)");
1395 MODULE_PARM_DESC(max_luns, "number of SCSI LUNs per target to simulate");
1396 MODULE_PARM_DESC(num_parts, "number of partitions(def=0)");
1397 MODULE_PARM_DESC(num_tgts, "number of SCSI targets per host to simulate");
1398 MODULE_PARM_DESC(opts, "1->noise, 2->medium_error, 4->...");
1399 MODULE_PARM_DESC(ptype, "SCSI peripheral type(def=0[disk])");
1400 MODULE_PARM_DESC(scsi_level, "SCSI level to simulate(def=5[SPC-3])");
1401 
1402 
1403 static char sdebug_info[256];
1404 
1405 static const char * scsi_debug_info(struct Scsi_Host * shp)
1406 {
1407 	sprintf(sdebug_info, "scsi_debug, version %s [%s], "
1408 		"dev_size_mb=%d, opts=0x%x", SCSI_DEBUG_VERSION,
1409 		scsi_debug_version_date, scsi_debug_dev_size_mb,
1410 		scsi_debug_opts);
1411 	return sdebug_info;
1412 }
1413 
1414 /* scsi_debug_proc_info
1415  * Used if the driver currently has no own support for /proc/scsi
1416  */
1417 static int scsi_debug_proc_info(struct Scsi_Host *host, char *buffer, char **start, off_t offset,
1418 				int length, int inout)
1419 {
1420 	int len, pos, begin;
1421 	int orig_length;
1422 
1423 	orig_length = length;
1424 
1425 	if (inout == 1) {
1426 		char arr[16];
1427 		int minLen = length > 15 ? 15 : length;
1428 
1429 		if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1430 			return -EACCES;
1431 		memcpy(arr, buffer, minLen);
1432 		arr[minLen] = '\0';
1433 		if (1 != sscanf(arr, "%d", &pos))
1434 			return -EINVAL;
1435 		scsi_debug_opts = pos;
1436 		if (scsi_debug_every_nth != 0)
1437                         scsi_debug_cmnd_count = 0;
1438 		return length;
1439 	}
1440 	begin = 0;
1441 	pos = len = sprintf(buffer, "scsi_debug adapter driver, version "
1442 	    "%s [%s]\n"
1443 	    "num_tgts=%d, shared (ram) size=%d MB, opts=0x%x, "
1444 	    "every_nth=%d(curr:%d)\n"
1445 	    "delay=%d, max_luns=%d, scsi_level=%d\n"
1446 	    "sector_size=%d bytes, cylinders=%d, heads=%d, sectors=%d\n"
1447 	    "number of aborts=%d, device_reset=%d, bus_resets=%d, "
1448 	    "host_resets=%d\n",
1449 	    SCSI_DEBUG_VERSION, scsi_debug_version_date, scsi_debug_num_tgts,
1450 	    scsi_debug_dev_size_mb, scsi_debug_opts, scsi_debug_every_nth,
1451 	    scsi_debug_cmnd_count, scsi_debug_delay,
1452 	    scsi_debug_max_luns, scsi_debug_scsi_level,
1453 	    SECT_SIZE, sdebug_cylinders_per, sdebug_heads, sdebug_sectors_per,
1454 	    num_aborts, num_dev_resets, num_bus_resets, num_host_resets);
1455 	if (pos < offset) {
1456 		len = 0;
1457 		begin = pos;
1458 	}
1459 	*start = buffer + (offset - begin);	/* Start of wanted data */
1460 	len -= (offset - begin);
1461 	if (len > length)
1462 		len = length;
1463 	return len;
1464 }
1465 
1466 static ssize_t sdebug_delay_show(struct device_driver * ddp, char * buf)
1467 {
1468         return scnprintf(buf, PAGE_SIZE, "%d\n", scsi_debug_delay);
1469 }
1470 
1471 static ssize_t sdebug_delay_store(struct device_driver * ddp,
1472 				  const char * buf, size_t count)
1473 {
1474         int delay;
1475 	char work[20];
1476 
1477         if (1 == sscanf(buf, "%10s", work)) {
1478 		if ((1 == sscanf(work, "%d", &delay)) && (delay >= 0)) {
1479 			scsi_debug_delay = delay;
1480 			return count;
1481 		}
1482 	}
1483 	return -EINVAL;
1484 }
1485 DRIVER_ATTR(delay, S_IRUGO | S_IWUSR, sdebug_delay_show,
1486 	    sdebug_delay_store);
1487 
1488 static ssize_t sdebug_opts_show(struct device_driver * ddp, char * buf)
1489 {
1490         return scnprintf(buf, PAGE_SIZE, "0x%x\n", scsi_debug_opts);
1491 }
1492 
1493 static ssize_t sdebug_opts_store(struct device_driver * ddp,
1494 				 const char * buf, size_t count)
1495 {
1496         int opts;
1497 	char work[20];
1498 
1499         if (1 == sscanf(buf, "%10s", work)) {
1500 		if (0 == strnicmp(work,"0x", 2)) {
1501 			if (1 == sscanf(&work[2], "%x", &opts))
1502 				goto opts_done;
1503 		} else {
1504 			if (1 == sscanf(work, "%d", &opts))
1505 				goto opts_done;
1506 		}
1507 	}
1508 	return -EINVAL;
1509 opts_done:
1510 	scsi_debug_opts = opts;
1511 	scsi_debug_cmnd_count = 0;
1512 	return count;
1513 }
1514 DRIVER_ATTR(opts, S_IRUGO | S_IWUSR, sdebug_opts_show,
1515 	    sdebug_opts_store);
1516 
1517 static ssize_t sdebug_ptype_show(struct device_driver * ddp, char * buf)
1518 {
1519         return scnprintf(buf, PAGE_SIZE, "%d\n", scsi_debug_ptype);
1520 }
1521 static ssize_t sdebug_ptype_store(struct device_driver * ddp,
1522 				  const char * buf, size_t count)
1523 {
1524         int n;
1525 
1526 	if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
1527 		scsi_debug_ptype = n;
1528 		return count;
1529 	}
1530 	return -EINVAL;
1531 }
1532 DRIVER_ATTR(ptype, S_IRUGO | S_IWUSR, sdebug_ptype_show, sdebug_ptype_store);
1533 
1534 static ssize_t sdebug_dsense_show(struct device_driver * ddp, char * buf)
1535 {
1536         return scnprintf(buf, PAGE_SIZE, "%d\n", scsi_debug_dsense);
1537 }
1538 static ssize_t sdebug_dsense_store(struct device_driver * ddp,
1539 				  const char * buf, size_t count)
1540 {
1541         int n;
1542 
1543 	if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
1544 		scsi_debug_dsense = n;
1545 		return count;
1546 	}
1547 	return -EINVAL;
1548 }
1549 DRIVER_ATTR(dsense, S_IRUGO | S_IWUSR, sdebug_dsense_show,
1550 	    sdebug_dsense_store);
1551 
1552 static ssize_t sdebug_num_tgts_show(struct device_driver * ddp, char * buf)
1553 {
1554         return scnprintf(buf, PAGE_SIZE, "%d\n", scsi_debug_num_tgts);
1555 }
1556 static ssize_t sdebug_num_tgts_store(struct device_driver * ddp,
1557 				     const char * buf, size_t count)
1558 {
1559         int n;
1560 
1561 	if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
1562 		scsi_debug_num_tgts = n;
1563 		sdebug_max_tgts_luns();
1564 		return count;
1565 	}
1566 	return -EINVAL;
1567 }
1568 DRIVER_ATTR(num_tgts, S_IRUGO | S_IWUSR, sdebug_num_tgts_show,
1569 	    sdebug_num_tgts_store);
1570 
1571 static ssize_t sdebug_dev_size_mb_show(struct device_driver * ddp, char * buf)
1572 {
1573         return scnprintf(buf, PAGE_SIZE, "%d\n", scsi_debug_dev_size_mb);
1574 }
1575 DRIVER_ATTR(dev_size_mb, S_IRUGO, sdebug_dev_size_mb_show, NULL);
1576 
1577 static ssize_t sdebug_num_parts_show(struct device_driver * ddp, char * buf)
1578 {
1579         return scnprintf(buf, PAGE_SIZE, "%d\n", scsi_debug_num_parts);
1580 }
1581 DRIVER_ATTR(num_parts, S_IRUGO, sdebug_num_parts_show, NULL);
1582 
1583 static ssize_t sdebug_every_nth_show(struct device_driver * ddp, char * buf)
1584 {
1585         return scnprintf(buf, PAGE_SIZE, "%d\n", scsi_debug_every_nth);
1586 }
1587 static ssize_t sdebug_every_nth_store(struct device_driver * ddp,
1588 				      const char * buf, size_t count)
1589 {
1590         int nth;
1591 
1592 	if ((count > 0) && (1 == sscanf(buf, "%d", &nth))) {
1593 		scsi_debug_every_nth = nth;
1594 		scsi_debug_cmnd_count = 0;
1595 		return count;
1596 	}
1597 	return -EINVAL;
1598 }
1599 DRIVER_ATTR(every_nth, S_IRUGO | S_IWUSR, sdebug_every_nth_show,
1600 	    sdebug_every_nth_store);
1601 
1602 static ssize_t sdebug_max_luns_show(struct device_driver * ddp, char * buf)
1603 {
1604         return scnprintf(buf, PAGE_SIZE, "%d\n", scsi_debug_max_luns);
1605 }
1606 static ssize_t sdebug_max_luns_store(struct device_driver * ddp,
1607 				     const char * buf, size_t count)
1608 {
1609         int n;
1610 
1611 	if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
1612 		scsi_debug_max_luns = n;
1613 		sdebug_max_tgts_luns();
1614 		return count;
1615 	}
1616 	return -EINVAL;
1617 }
1618 DRIVER_ATTR(max_luns, S_IRUGO | S_IWUSR, sdebug_max_luns_show,
1619 	    sdebug_max_luns_store);
1620 
1621 static ssize_t sdebug_scsi_level_show(struct device_driver * ddp, char * buf)
1622 {
1623         return scnprintf(buf, PAGE_SIZE, "%d\n", scsi_debug_scsi_level);
1624 }
1625 DRIVER_ATTR(scsi_level, S_IRUGO, sdebug_scsi_level_show, NULL);
1626 
1627 static ssize_t sdebug_add_host_show(struct device_driver * ddp, char * buf)
1628 {
1629         return scnprintf(buf, PAGE_SIZE, "%d\n", scsi_debug_add_host);
1630 }
1631 
1632 static ssize_t sdebug_add_host_store(struct device_driver * ddp,
1633 				     const char * buf, size_t count)
1634 {
1635         int delta_hosts;
1636 	char work[20];
1637 
1638         if (1 != sscanf(buf, "%10s", work))
1639 		return -EINVAL;
1640 	{	/* temporary hack around sscanf() problem with -ve nums */
1641 		int neg = 0;
1642 
1643 		if ('-' == *work)
1644 			neg = 1;
1645 		if (1 != sscanf(work + neg, "%d", &delta_hosts))
1646 			return -EINVAL;
1647 		if (neg)
1648 			delta_hosts = -delta_hosts;
1649 	}
1650 	if (delta_hosts > 0) {
1651 		do {
1652 			sdebug_add_adapter();
1653 		} while (--delta_hosts);
1654 	} else if (delta_hosts < 0) {
1655 		do {
1656 			sdebug_remove_adapter();
1657 		} while (++delta_hosts);
1658 	}
1659 	return count;
1660 }
1661 DRIVER_ATTR(add_host, S_IRUGO | S_IWUSR, sdebug_add_host_show,
1662 	    sdebug_add_host_store);
1663 
1664 static void do_create_driverfs_files(void)
1665 {
1666 	driver_create_file(&sdebug_driverfs_driver, &driver_attr_add_host);
1667 	driver_create_file(&sdebug_driverfs_driver, &driver_attr_delay);
1668 	driver_create_file(&sdebug_driverfs_driver, &driver_attr_dev_size_mb);
1669 	driver_create_file(&sdebug_driverfs_driver, &driver_attr_dsense);
1670 	driver_create_file(&sdebug_driverfs_driver, &driver_attr_every_nth);
1671 	driver_create_file(&sdebug_driverfs_driver, &driver_attr_max_luns);
1672 	driver_create_file(&sdebug_driverfs_driver, &driver_attr_num_tgts);
1673 	driver_create_file(&sdebug_driverfs_driver, &driver_attr_num_parts);
1674 	driver_create_file(&sdebug_driverfs_driver, &driver_attr_ptype);
1675 	driver_create_file(&sdebug_driverfs_driver, &driver_attr_opts);
1676 	driver_create_file(&sdebug_driverfs_driver, &driver_attr_scsi_level);
1677 }
1678 
1679 static void do_remove_driverfs_files(void)
1680 {
1681 	driver_remove_file(&sdebug_driverfs_driver, &driver_attr_scsi_level);
1682 	driver_remove_file(&sdebug_driverfs_driver, &driver_attr_opts);
1683 	driver_remove_file(&sdebug_driverfs_driver, &driver_attr_ptype);
1684 	driver_remove_file(&sdebug_driverfs_driver, &driver_attr_num_parts);
1685 	driver_remove_file(&sdebug_driverfs_driver, &driver_attr_num_tgts);
1686 	driver_remove_file(&sdebug_driverfs_driver, &driver_attr_max_luns);
1687 	driver_remove_file(&sdebug_driverfs_driver, &driver_attr_every_nth);
1688 	driver_remove_file(&sdebug_driverfs_driver, &driver_attr_dsense);
1689 	driver_remove_file(&sdebug_driverfs_driver, &driver_attr_dev_size_mb);
1690 	driver_remove_file(&sdebug_driverfs_driver, &driver_attr_delay);
1691 	driver_remove_file(&sdebug_driverfs_driver, &driver_attr_add_host);
1692 }
1693 
1694 static int __init scsi_debug_init(void)
1695 {
1696 	unsigned long sz;
1697 	int host_to_add;
1698 	int k;
1699 
1700 	if (scsi_debug_dev_size_mb < 1)
1701 		scsi_debug_dev_size_mb = 1;  /* force minimum 1 MB ramdisk */
1702 	sdebug_store_size = (unsigned long)scsi_debug_dev_size_mb * 1048576;
1703 	sdebug_capacity = sdebug_store_size / SECT_SIZE;
1704 
1705 	/* play around with geometry, don't waste too much on track 0 */
1706 	sdebug_heads = 8;
1707 	sdebug_sectors_per = 32;
1708 	if (scsi_debug_dev_size_mb >= 16)
1709 		sdebug_heads = 32;
1710 	else if (scsi_debug_dev_size_mb >= 256)
1711 		sdebug_heads = 64;
1712 	sdebug_cylinders_per = (unsigned long)sdebug_capacity /
1713 			       (sdebug_sectors_per * sdebug_heads);
1714 	if (sdebug_cylinders_per >= 1024) {
1715 		/* other LLDs do this; implies >= 1GB ram disk ... */
1716 		sdebug_heads = 255;
1717 		sdebug_sectors_per = 63;
1718 		sdebug_cylinders_per = (unsigned long)sdebug_capacity /
1719 			       (sdebug_sectors_per * sdebug_heads);
1720 	}
1721 
1722 	sz = sdebug_store_size;
1723 	fake_storep = vmalloc(sz);
1724 	if (NULL == fake_storep) {
1725 		printk(KERN_ERR "scsi_debug_init: out of memory, 1\n");
1726 		return -ENOMEM;
1727 	}
1728 	memset(fake_storep, 0, sz);
1729 	if (scsi_debug_num_parts > 0)
1730 		sdebug_build_parts(fake_storep);
1731 
1732 	init_all_queued();
1733 
1734 	device_register(&pseudo_primary);
1735 	bus_register(&pseudo_lld_bus);
1736 	driver_register(&sdebug_driverfs_driver);
1737 	do_create_driverfs_files();
1738 
1739 	sdebug_driver_template.proc_name = (char *)sdebug_proc_name;
1740 
1741 	host_to_add = scsi_debug_add_host;
1742         scsi_debug_add_host = 0;
1743 
1744         for (k = 0; k < host_to_add; k++) {
1745                 if (sdebug_add_adapter()) {
1746                         printk(KERN_ERR "scsi_debug_init: "
1747                                "sdebug_add_adapter failed k=%d\n", k);
1748                         break;
1749                 }
1750         }
1751 
1752 	if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts) {
1753 		printk(KERN_INFO "scsi_debug_init: built %d host(s)\n",
1754 		       scsi_debug_add_host);
1755 	}
1756 	return 0;
1757 }
1758 
1759 static void __exit scsi_debug_exit(void)
1760 {
1761 	int k = scsi_debug_add_host;
1762 
1763 	stop_all_queued();
1764 	for (; k; k--)
1765 		sdebug_remove_adapter();
1766 	do_remove_driverfs_files();
1767 	driver_unregister(&sdebug_driverfs_driver);
1768 	bus_unregister(&pseudo_lld_bus);
1769 	device_unregister(&pseudo_primary);
1770 
1771 	vfree(fake_storep);
1772 }
1773 
1774 device_initcall(scsi_debug_init);
1775 module_exit(scsi_debug_exit);
1776 
1777 static void pseudo_0_release(struct device * dev)
1778 {
1779 	if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
1780 		printk(KERN_INFO "scsi_debug: pseudo_0_release() called\n");
1781 }
1782 
1783 static struct device pseudo_primary = {
1784 	.bus_id		= "pseudo_0",
1785 	.release	= pseudo_0_release,
1786 };
1787 
1788 static int pseudo_lld_bus_match(struct device *dev,
1789                           struct device_driver *dev_driver)
1790 {
1791         return 1;
1792 }
1793 
1794 static struct bus_type pseudo_lld_bus = {
1795         .name = "pseudo",
1796         .match = pseudo_lld_bus_match,
1797 	.probe = sdebug_driver_probe,
1798 	.remove = sdebug_driver_remove,
1799 };
1800 
1801 static void sdebug_release_adapter(struct device * dev)
1802 {
1803         struct sdebug_host_info *sdbg_host;
1804 
1805 	sdbg_host = to_sdebug_host(dev);
1806         kfree(sdbg_host);
1807 }
1808 
1809 static int sdebug_add_adapter(void)
1810 {
1811 	int k, devs_per_host;
1812         int error = 0;
1813         struct sdebug_host_info *sdbg_host;
1814         struct sdebug_dev_info *sdbg_devinfo;
1815         struct list_head *lh, *lh_sf;
1816 
1817         sdbg_host = kmalloc(sizeof(*sdbg_host),GFP_KERNEL);
1818 
1819         if (NULL == sdbg_host) {
1820                 printk(KERN_ERR "%s: out of memory at line %d\n",
1821                        __FUNCTION__, __LINE__);
1822                 return -ENOMEM;
1823         }
1824 
1825         memset(sdbg_host, 0, sizeof(*sdbg_host));
1826         INIT_LIST_HEAD(&sdbg_host->dev_info_list);
1827 
1828 	devs_per_host = scsi_debug_num_tgts * scsi_debug_max_luns;
1829         for (k = 0; k < devs_per_host; k++) {
1830                 sdbg_devinfo = kmalloc(sizeof(*sdbg_devinfo),GFP_KERNEL);
1831                 if (NULL == sdbg_devinfo) {
1832                         printk(KERN_ERR "%s: out of memory at line %d\n",
1833                                __FUNCTION__, __LINE__);
1834                         error = -ENOMEM;
1835 			goto clean;
1836                 }
1837                 memset(sdbg_devinfo, 0, sizeof(*sdbg_devinfo));
1838                 sdbg_devinfo->sdbg_host = sdbg_host;
1839                 list_add_tail(&sdbg_devinfo->dev_list,
1840                               &sdbg_host->dev_info_list);
1841         }
1842 
1843         spin_lock(&sdebug_host_list_lock);
1844         list_add_tail(&sdbg_host->host_list, &sdebug_host_list);
1845         spin_unlock(&sdebug_host_list_lock);
1846 
1847         sdbg_host->dev.bus = &pseudo_lld_bus;
1848         sdbg_host->dev.parent = &pseudo_primary;
1849         sdbg_host->dev.release = &sdebug_release_adapter;
1850         sprintf(sdbg_host->dev.bus_id, "adapter%d", scsi_debug_add_host);
1851 
1852         error = device_register(&sdbg_host->dev);
1853 
1854         if (error)
1855 		goto clean;
1856 
1857 	++scsi_debug_add_host;
1858         return error;
1859 
1860 clean:
1861 	list_for_each_safe(lh, lh_sf, &sdbg_host->dev_info_list) {
1862 		sdbg_devinfo = list_entry(lh, struct sdebug_dev_info,
1863 					  dev_list);
1864 		list_del(&sdbg_devinfo->dev_list);
1865 		kfree(sdbg_devinfo);
1866 	}
1867 
1868 	kfree(sdbg_host);
1869         return error;
1870 }
1871 
1872 static void sdebug_remove_adapter(void)
1873 {
1874         struct sdebug_host_info * sdbg_host = NULL;
1875 
1876         spin_lock(&sdebug_host_list_lock);
1877         if (!list_empty(&sdebug_host_list)) {
1878                 sdbg_host = list_entry(sdebug_host_list.prev,
1879                                        struct sdebug_host_info, host_list);
1880 		list_del(&sdbg_host->host_list);
1881 	}
1882         spin_unlock(&sdebug_host_list_lock);
1883 
1884 	if (!sdbg_host)
1885 		return;
1886 
1887         device_unregister(&sdbg_host->dev);
1888         --scsi_debug_add_host;
1889 }
1890 
1891 static int sdebug_driver_probe(struct device * dev)
1892 {
1893         int error = 0;
1894         struct sdebug_host_info *sdbg_host;
1895         struct Scsi_Host *hpnt;
1896 
1897 	sdbg_host = to_sdebug_host(dev);
1898 
1899         hpnt = scsi_host_alloc(&sdebug_driver_template, sizeof(sdbg_host));
1900         if (NULL == hpnt) {
1901                 printk(KERN_ERR "%s: scsi_register failed\n", __FUNCTION__);
1902                 error = -ENODEV;
1903 		return error;
1904         }
1905 
1906         sdbg_host->shost = hpnt;
1907 	*((struct sdebug_host_info **)hpnt->hostdata) = sdbg_host;
1908 	if ((hpnt->this_id >= 0) && (scsi_debug_num_tgts > hpnt->this_id))
1909 		hpnt->max_id = scsi_debug_num_tgts + 1;
1910 	else
1911 		hpnt->max_id = scsi_debug_num_tgts;
1912 	hpnt->max_lun = scsi_debug_max_luns;
1913 
1914         error = scsi_add_host(hpnt, &sdbg_host->dev);
1915         if (error) {
1916                 printk(KERN_ERR "%s: scsi_add_host failed\n", __FUNCTION__);
1917                 error = -ENODEV;
1918 		scsi_host_put(hpnt);
1919         } else
1920 		scsi_scan_host(hpnt);
1921 
1922 
1923         return error;
1924 }
1925 
1926 static int sdebug_driver_remove(struct device * dev)
1927 {
1928         struct list_head *lh, *lh_sf;
1929         struct sdebug_host_info *sdbg_host;
1930         struct sdebug_dev_info *sdbg_devinfo;
1931 
1932 	sdbg_host = to_sdebug_host(dev);
1933 
1934 	if (!sdbg_host) {
1935 		printk(KERN_ERR "%s: Unable to locate host info\n",
1936 		       __FUNCTION__);
1937 		return -ENODEV;
1938 	}
1939 
1940         scsi_remove_host(sdbg_host->shost);
1941 
1942         list_for_each_safe(lh, lh_sf, &sdbg_host->dev_info_list) {
1943                 sdbg_devinfo = list_entry(lh, struct sdebug_dev_info,
1944                                           dev_list);
1945                 list_del(&sdbg_devinfo->dev_list);
1946                 kfree(sdbg_devinfo);
1947         }
1948 
1949         scsi_host_put(sdbg_host->shost);
1950         return 0;
1951 }
1952 
1953 static void sdebug_max_tgts_luns(void)
1954 {
1955 	struct sdebug_host_info * sdbg_host;
1956 	struct Scsi_Host *hpnt;
1957 
1958 	spin_lock(&sdebug_host_list_lock);
1959 	list_for_each_entry(sdbg_host, &sdebug_host_list, host_list) {
1960 		hpnt = sdbg_host->shost;
1961 		if ((hpnt->this_id >= 0) &&
1962 		    (scsi_debug_num_tgts > hpnt->this_id))
1963 			hpnt->max_id = scsi_debug_num_tgts + 1;
1964 		else
1965 			hpnt->max_id = scsi_debug_num_tgts;
1966 		hpnt->max_lun = scsi_debug_max_luns;
1967 	}
1968 	spin_unlock(&sdebug_host_list_lock);
1969 }
1970