xref: /linux/drivers/scsi/scsi_devinfo.c (revision 87c2ce3b9305b9b723faeedf6e32ef703ec9b33a)
1 
2 #include <linux/blkdev.h>
3 #include <linux/init.h>
4 #include <linux/kernel.h>
5 #include <linux/module.h>
6 #include <linux/moduleparam.h>
7 #include <linux/proc_fs.h>
8 #include <linux/seq_file.h>
9 
10 #include <scsi/scsi_device.h>
11 #include <scsi/scsi_devinfo.h>
12 
13 #include "scsi_priv.h"
14 
15 
16 /*
17  * scsi_dev_info_list: structure to hold black/white listed devices.
18  */
19 struct scsi_dev_info_list {
20 	struct list_head dev_info_list;
21 	char vendor[8];
22 	char model[16];
23 	unsigned flags;
24 	unsigned compatible; /* for use with scsi_static_device_list entries */
25 };
26 
27 
28 static const char spaces[] = "                "; /* 16 of them */
29 static unsigned scsi_default_dev_flags;
30 static LIST_HEAD(scsi_dev_info_list);
31 static char scsi_dev_flags[256];
32 
33 /*
34  * scsi_static_device_list: deprecated list of devices that require
35  * settings that differ from the default, includes black-listed (broken)
36  * devices. The entries here are added to the tail of scsi_dev_info_list
37  * via scsi_dev_info_list_init.
38  *
39  * Do not add to this list, use the command line or proc interface to add
40  * to the scsi_dev_info_list. This table will eventually go away.
41  */
42 static struct {
43 	char *vendor;
44 	char *model;
45 	char *revision;	/* revision known to be bad, unused */
46 	unsigned flags;
47 } scsi_static_device_list[] __initdata = {
48 	/*
49 	 * The following devices are known not to tolerate a lun != 0 scan
50 	 * for one reason or another. Some will respond to all luns,
51 	 * others will lock up.
52 	 */
53 	{"Aashima", "IMAGERY 2400SP", "1.03", BLIST_NOLUN},	/* locks up */
54 	{"CHINON", "CD-ROM CDS-431", "H42", BLIST_NOLUN},	/* locks up */
55 	{"CHINON", "CD-ROM CDS-535", "Q14", BLIST_NOLUN},	/* locks up */
56 	{"DENON", "DRD-25X", "V", BLIST_NOLUN},			/* locks up */
57 	{"HITACHI", "DK312C", "CM81", BLIST_NOLUN},	/* responds to all lun */
58 	{"HITACHI", "DK314C", "CR21", BLIST_NOLUN},	/* responds to all lun */
59 	{"IMS", "CDD521/10", "2.06", BLIST_NOLUN},	/* locks up */
60 	{"MAXTOR", "XT-3280", "PR02", BLIST_NOLUN},	/* locks up */
61 	{"MAXTOR", "XT-4380S", "B3C", BLIST_NOLUN},	/* locks up */
62 	{"MAXTOR", "MXT-1240S", "I1.2", BLIST_NOLUN},	/* locks up */
63 	{"MAXTOR", "XT-4170S", "B5A", BLIST_NOLUN},	/* locks up */
64 	{"MAXTOR", "XT-8760S", "B7B", BLIST_NOLUN},	/* locks up */
65 	{"MEDIAVIS", "RENO CD-ROMX2A", "2.03", BLIST_NOLUN},	/* responds to all lun */
66 	{"MICROTEK", "ScanMakerIII", "2.30", BLIST_NOLUN},	/* responds to all lun */
67 	{"NEC", "CD-ROM DRIVE:841", "1.0", BLIST_NOLUN},/* locks up */
68 	{"PHILIPS", "PCA80SC", "V4-2", BLIST_NOLUN},	/* responds to all lun */
69 	{"RODIME", "RO3000S", "2.33", BLIST_NOLUN},	/* locks up */
70 	{"SUN", "SENA", NULL, BLIST_NOLUN},		/* responds to all luns */
71 	/*
72 	 * The following causes a failed REQUEST SENSE on lun 1 for
73 	 * aha152x controller, which causes SCSI code to reset bus.
74 	 */
75 	{"SANYO", "CRD-250S", "1.20", BLIST_NOLUN},
76 	/*
77 	 * The following causes a failed REQUEST SENSE on lun 1 for
78 	 * aha152x controller, which causes SCSI code to reset bus.
79 	 */
80 	{"SEAGATE", "ST157N", "\004|j", BLIST_NOLUN},
81 	{"SEAGATE", "ST296", "921", BLIST_NOLUN},	/* responds to all lun */
82 	{"SEAGATE", "ST1581", "6538", BLIST_NOLUN},	/* responds to all lun */
83 	{"SONY", "CD-ROM CDU-541", "4.3d", BLIST_NOLUN},
84 	{"SONY", "CD-ROM CDU-55S", "1.0i", BLIST_NOLUN},
85 	{"SONY", "CD-ROM CDU-561", "1.7x", BLIST_NOLUN},
86 	{"SONY", "CD-ROM CDU-8012", NULL, BLIST_NOLUN},
87 	{"SONY", "SDT-5000", "3.17", BLIST_SELECT_NO_ATN},
88 	{"TANDBERG", "TDC 3600", "U07", BLIST_NOLUN},	/* locks up */
89 	{"TEAC", "CD-R55S", "1.0H", BLIST_NOLUN},	/* locks up */
90 	/*
91 	 * The following causes a failed REQUEST SENSE on lun 1 for
92 	 * seagate controller, which causes SCSI code to reset bus.
93 	 */
94 	{"TEAC", "CD-ROM", "1.06", BLIST_NOLUN},
95 	{"TEAC", "MT-2ST/45S2-27", "RV M", BLIST_NOLUN},	/* responds to all lun */
96 	/*
97 	 * The following causes a failed REQUEST SENSE on lun 1 for
98 	 * seagate controller, which causes SCSI code to reset bus.
99 	 */
100 	{"HP", "C1750A", "3226", BLIST_NOLUN},		/* scanjet iic */
101 	{"HP", "C1790A", "", BLIST_NOLUN},		/* scanjet iip */
102 	{"HP", "C2500A", "", BLIST_NOLUN},		/* scanjet iicx */
103 	{"MEDIAVIS", "CDR-H93MV", "1.31", BLIST_NOLUN},	/* locks up */
104 	{"MICROTEK", "ScanMaker II", "5.61", BLIST_NOLUN},	/* responds to all lun */
105 	{"MITSUMI", "CD-R CR-2201CS", "6119", BLIST_NOLUN},	/* locks up */
106 	{"NEC", "D3856", "0009", BLIST_NOLUN},
107 	{"QUANTUM", "LPS525S", "3110", BLIST_NOLUN},	/* locks up */
108 	{"QUANTUM", "PD1225S", "3110", BLIST_NOLUN},	/* locks up */
109 	{"QUANTUM", "FIREBALL ST4.3S", "0F0C", BLIST_NOLUN},	/* locks up */
110 	{"RELISYS", "Scorpio", NULL, BLIST_NOLUN},	/* responds to all lun */
111 	{"SANKYO", "CP525", "6.64", BLIST_NOLUN},	/* causes failed REQ SENSE, extra reset */
112 	{"TEXEL", "CD-ROM", "1.06", BLIST_NOLUN},
113 	{"transtec", "T5008", "0001", BLIST_NOREPORTLUN },
114 	{"YAMAHA", "CDR100", "1.00", BLIST_NOLUN},	/* locks up */
115 	{"YAMAHA", "CDR102", "1.00", BLIST_NOLUN},	/* locks up */
116 	{"YAMAHA", "CRW8424S", "1.0", BLIST_NOLUN},	/* locks up */
117 	{"YAMAHA", "CRW6416S", "1.0c", BLIST_NOLUN},	/* locks up */
118 	{"", "Scanner", "1.80", BLIST_NOLUN},	/* responds to all lun */
119 
120 	/*
121 	 * Other types of devices that have special flags.
122 	 * Note that all USB devices should have the BLIST_INQUIRY_36 flag.
123 	 */
124 	{"3PARdata", "VV", NULL, BLIST_REPORTLUN2},
125 	{"ADAPTEC", "AACRAID", NULL, BLIST_FORCELUN},
126 	{"ADAPTEC", "Adaptec 5400S", NULL, BLIST_FORCELUN},
127 	{"AFT PRO", "-IX CF", "0.0>", BLIST_FORCELUN},
128 	{"BELKIN", "USB 2 HS-CF", "1.95",  BLIST_FORCELUN | BLIST_INQUIRY_36},
129 	{"CANON", "IPUBJD", NULL, BLIST_SPARSELUN},
130 	{"CBOX3", "USB Storage-SMC", "300A", BLIST_FORCELUN | BLIST_INQUIRY_36},
131 	{"CMD", "CRA-7280", NULL, BLIST_SPARSELUN},	/* CMD RAID Controller */
132 	{"CNSI", "G7324", NULL, BLIST_SPARSELUN},	/* Chaparral G7324 RAID */
133 	{"CNSi", "G8324", NULL, BLIST_SPARSELUN},	/* Chaparral G8324 RAID */
134 	{"COMPAQ", "LOGICAL VOLUME", NULL, BLIST_FORCELUN},
135 	{"COMPAQ", "CR3500", NULL, BLIST_FORCELUN},
136 	{"COMPAQ", "MSA1000", NULL, BLIST_SPARSELUN | BLIST_NOSTARTONADD},
137 	{"COMPAQ", "MSA1000 VOLUME", NULL, BLIST_SPARSELUN | BLIST_NOSTARTONADD},
138 	{"COMPAQ", "HSV110", NULL, BLIST_REPORTLUN2 | BLIST_NOSTARTONADD},
139 	{"DDN", "SAN DataDirector", "*", BLIST_SPARSELUN},
140 	{"DEC", "HSG80", NULL, BLIST_REPORTLUN2 | BLIST_NOSTARTONADD},
141 	{"DELL", "PV660F", NULL, BLIST_SPARSELUN},
142 	{"DELL", "PV660F   PSEUDO", NULL, BLIST_SPARSELUN},
143 	{"DELL", "PSEUDO DEVICE .", NULL, BLIST_SPARSELUN},	/* Dell PV 530F */
144 	{"DELL", "PV530F", NULL, BLIST_SPARSELUN},
145 	{"DELL", "PERCRAID", NULL, BLIST_FORCELUN},
146 	{"DGC", "RAID", NULL, BLIST_SPARSELUN},	/* Dell PV 650F, storage on LUN 0 */
147 	{"DGC", "DISK", NULL, BLIST_SPARSELUN},	/* Dell PV 650F, no storage on LUN 0 */
148 	{"EMC", "SYMMETRIX", NULL, BLIST_SPARSELUN | BLIST_LARGELUN | BLIST_FORCELUN},
149 	{"EMULEX", "MD21/S2     ESDI", NULL, BLIST_SINGLELUN},
150 	{"FSC", "CentricStor", "*", BLIST_SPARSELUN | BLIST_LARGELUN},
151 	{"Generic", "USB SD Reader", "1.00", BLIST_FORCELUN | BLIST_INQUIRY_36},
152 	{"Generic", "USB Storage-SMC", "0180", BLIST_FORCELUN | BLIST_INQUIRY_36},
153 	{"Generic", "USB Storage-SMC", "0207", BLIST_FORCELUN | BLIST_INQUIRY_36},
154 	{"HITACHI", "DF400", "*", BLIST_SPARSELUN},
155 	{"HITACHI", "DF500", "*", BLIST_SPARSELUN},
156 	{"HITACHI", "DF600", "*", BLIST_SPARSELUN},
157 	{"HP", "A6189A", NULL, BLIST_SPARSELUN | BLIST_LARGELUN},	/* HP VA7400 */
158 	{"HP", "OPEN-", "*", BLIST_SPARSELUN | BLIST_LARGELUN}, /* HP XP Arrays */
159 	{"HP", "NetRAID-4M", NULL, BLIST_FORCELUN},
160 	{"HP", "HSV100", NULL, BLIST_REPORTLUN2 | BLIST_NOSTARTONADD},
161 	{"HP", "C1557A", NULL, BLIST_FORCELUN},
162 	{"HP", "C3323-300", "4269", BLIST_NOTQ},
163 	{"IBM", "AuSaV1S2", NULL, BLIST_FORCELUN},
164 	{"IBM", "ProFibre 4000R", "*", BLIST_SPARSELUN | BLIST_LARGELUN},
165 	{"IBM", "2105", NULL, BLIST_RETRY_HWERROR},
166 	{"iomega", "jaz 1GB", "J.86", BLIST_NOTQ | BLIST_NOLUN},
167 	{"IOMEGA", "Io20S         *F", NULL, BLIST_KEY},
168 	{"INSITE", "Floptical   F*8I", NULL, BLIST_KEY},
169 	{"INSITE", "I325VM", NULL, BLIST_KEY},
170 	{"iRiver", "iFP Mass Driver", NULL, BLIST_NOT_LOCKABLE | BLIST_INQUIRY_36},
171 	{"LASOUND", "CDX7405", "3.10", BLIST_MAX5LUN | BLIST_SINGLELUN},
172 	{"MATSHITA", "PD-1", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
173 	{"MATSHITA", "DMC-LC5", NULL, BLIST_NOT_LOCKABLE | BLIST_INQUIRY_36},
174 	{"MATSHITA", "DMC-LC40", NULL, BLIST_NOT_LOCKABLE | BLIST_INQUIRY_36},
175 	{"Medion", "Flash XL  MMC/SD", "2.6D", BLIST_FORCELUN},
176 	{"MegaRAID", "LD", NULL, BLIST_FORCELUN},
177 	{"MICROP", "4110", NULL, BLIST_NOTQ},
178 	{"MYLEX", "DACARMRB", "*", BLIST_REPORTLUN2},
179 	{"nCipher", "Fastness Crypto", NULL, BLIST_FORCELUN},
180 	{"NAKAMICH", "MJ-4.8S", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
181 	{"NAKAMICH", "MJ-5.16S", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
182 	{"NEC", "PD-1 ODX654P", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
183 	{"NRC", "MBR-7", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
184 	{"NRC", "MBR-7.4", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
185 	{"PIONEER", "CD-ROM DRM-600", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
186 	{"PIONEER", "CD-ROM DRM-602X", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
187 	{"PIONEER", "CD-ROM DRM-604X", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
188 	{"PIONEER", "CD-ROM DRM-624X", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
189 	{"REGAL", "CDC-4X", NULL, BLIST_MAX5LUN | BLIST_SINGLELUN},
190 	{"SanDisk", "ImageMate CF-SD1", NULL, BLIST_FORCELUN},
191 	{"SEAGATE", "ST34555N", "0930", BLIST_NOTQ},	/* Chokes on tagged INQUIRY */
192 	{"SEAGATE", "ST3390N", "9546", BLIST_NOTQ},
193 	{"SGI", "RAID3", "*", BLIST_SPARSELUN},
194 	{"SGI", "RAID5", "*", BLIST_SPARSELUN},
195 	{"SGI", "TP9100", "*", BLIST_REPORTLUN2},
196 	{"SGI", "Universal Xport", "*", BLIST_NO_ULD_ATTACH},
197 	{"IBM", "Universal Xport", "*", BLIST_NO_ULD_ATTACH},
198 	{"SMSC", "USB 2 HS-CF", NULL, BLIST_SPARSELUN | BLIST_INQUIRY_36},
199 	{"SONY", "CD-ROM CDU-8001", NULL, BLIST_BORKEN},
200 	{"SONY", "TSL", NULL, BLIST_FORCELUN},		/* DDS3 & DDS4 autoloaders */
201 	{"ST650211", "CF", NULL, BLIST_RETRY_HWERROR},
202 	{"SUN", "T300", "*", BLIST_SPARSELUN},
203 	{"SUN", "T4", "*", BLIST_SPARSELUN},
204 	{"TEXEL", "CD-ROM", "1.06", BLIST_BORKEN},
205 	{"TOSHIBA", "CDROM", NULL, BLIST_ISROM},
206 	{"TOSHIBA", "CD-ROM", NULL, BLIST_ISROM},
207 	{"USB2.0", "SMARTMEDIA/XD", NULL, BLIST_FORCELUN | BLIST_INQUIRY_36},
208 	{"WangDAT", "Model 2600", "01.7", BLIST_SELECT_NO_ATN},
209 	{"WangDAT", "Model 3200", "02.2", BLIST_SELECT_NO_ATN},
210 	{"WangDAT", "Model 1300", "02.4", BLIST_SELECT_NO_ATN},
211 	{"WDC WD25", "00JB-00FUA0", NULL, BLIST_NOREPORTLUN},
212 	{"XYRATEX", "RS", "*", BLIST_SPARSELUN | BLIST_LARGELUN},
213 	{"Zzyzx", "RocketStor 500S", NULL, BLIST_SPARSELUN},
214 	{"Zzyzx", "RocketStor 2000", NULL, BLIST_SPARSELUN},
215 	{ NULL, NULL, NULL, 0 },
216 };
217 
218 /*
219  * scsi_strcpy_devinfo: called from scsi_dev_info_list_add to copy into
220  * devinfo vendor and model strings.
221  */
222 static void scsi_strcpy_devinfo(char *name, char *to, size_t to_length,
223 				char *from, int compatible)
224 {
225 	size_t from_length;
226 
227 	from_length = strlen(from);
228 	strncpy(to, from, min(to_length, from_length));
229 	if (from_length < to_length) {
230 		if (compatible) {
231 			/*
232 			 * NUL terminate the string if it is short.
233 			 */
234 			to[from_length] = '\0';
235 		} else {
236 			/*
237 			 * space pad the string if it is short.
238 			 */
239 			strncpy(&to[from_length], spaces,
240 				to_length - from_length);
241 		}
242 	}
243 	if (from_length > to_length)
244 		 printk(KERN_WARNING "%s: %s string '%s' is too long\n",
245 			__FUNCTION__, name, from);
246 }
247 
248 /**
249  * scsi_dev_info_list_add: add one dev_info list entry.
250  * @vendor:	vendor string
251  * @model:	model (product) string
252  * @strflags:	integer string
253  * @flag:	if strflags NULL, use this flag value
254  *
255  * Description:
256  * 	Create and add one dev_info entry for @vendor, @model, @strflags or
257  * 	@flag. If @compatible, add to the tail of the list, do not space
258  * 	pad, and set devinfo->compatible. The scsi_static_device_list entries
259  * 	are added with @compatible 1 and @clfags NULL.
260  *
261  * Returns: 0 OK, -error on failure.
262  **/
263 static int scsi_dev_info_list_add(int compatible, char *vendor, char *model,
264 			    char *strflags, int flags)
265 {
266 	struct scsi_dev_info_list *devinfo;
267 
268 	devinfo = kmalloc(sizeof(*devinfo), GFP_KERNEL);
269 	if (!devinfo) {
270 		printk(KERN_ERR "%s: no memory\n", __FUNCTION__);
271 		return -ENOMEM;
272 	}
273 
274 	scsi_strcpy_devinfo("vendor", devinfo->vendor, sizeof(devinfo->vendor),
275 			    vendor, compatible);
276 	scsi_strcpy_devinfo("model", devinfo->model, sizeof(devinfo->model),
277 			    model, compatible);
278 
279 	if (strflags)
280 		devinfo->flags = simple_strtoul(strflags, NULL, 0);
281 	else
282 		devinfo->flags = flags;
283 
284 	devinfo->compatible = compatible;
285 
286 	if (compatible)
287 		list_add_tail(&devinfo->dev_info_list, &scsi_dev_info_list);
288 	else
289 		list_add(&devinfo->dev_info_list, &scsi_dev_info_list);
290 
291 	return 0;
292 }
293 
294 /**
295  * scsi_dev_info_list_add_str: parse dev_list and add to the
296  * scsi_dev_info_list.
297  * @dev_list:	string of device flags to add
298  *
299  * Description:
300  * 	Parse dev_list, and add entries to the scsi_dev_info_list.
301  * 	dev_list is of the form "vendor:product:flag,vendor:product:flag".
302  * 	dev_list is modified via strsep. Can be called for command line
303  * 	addition, for proc or mabye a sysfs interface.
304  *
305  * Returns: 0 if OK, -error on failure.
306  **/
307 static int scsi_dev_info_list_add_str(char *dev_list)
308 {
309 	char *vendor, *model, *strflags, *next;
310 	char *next_check;
311 	int res = 0;
312 
313 	next = dev_list;
314 	if (next && next[0] == '"') {
315 		/*
316 		 * Ignore both the leading and trailing quote.
317 		 */
318 		next++;
319 		next_check = ",\"";
320 	} else {
321 		next_check = ",";
322 	}
323 
324 	/*
325 	 * For the leading and trailing '"' case, the for loop comes
326 	 * through the last time with vendor[0] == '\0'.
327 	 */
328 	for (vendor = strsep(&next, ":"); vendor && (vendor[0] != '\0')
329 	     && (res == 0); vendor = strsep(&next, ":")) {
330 		strflags = NULL;
331 		model = strsep(&next, ":");
332 		if (model)
333 			strflags = strsep(&next, next_check);
334 		if (!model || !strflags) {
335 			printk(KERN_ERR "%s: bad dev info string '%s' '%s'"
336 			       " '%s'\n", __FUNCTION__, vendor, model,
337 			       strflags);
338 			res = -EINVAL;
339 		} else
340 			res = scsi_dev_info_list_add(0 /* compatible */, vendor,
341 						     model, strflags, 0);
342 	}
343 	return res;
344 }
345 
346 /**
347  * get_device_flags - get device specific flags from the dynamic device
348  * list. Called during scan time.
349  * @vendor:	vendor name
350  * @model:	model name
351  *
352  * Description:
353  *     Search the scsi_dev_info_list for an entry matching @vendor and
354  *     @model, if found, return the matching flags value, else return
355  *     the host or global default settings.
356  **/
357 int scsi_get_device_flags(struct scsi_device *sdev,
358 			  const unsigned char *vendor,
359 			  const unsigned char *model)
360 {
361 	struct scsi_dev_info_list *devinfo;
362 	unsigned int bflags;
363 
364 	bflags = sdev->sdev_bflags;
365 	if (!bflags)
366 		bflags = scsi_default_dev_flags;
367 
368 	list_for_each_entry(devinfo, &scsi_dev_info_list, dev_info_list) {
369 		if (devinfo->compatible) {
370 			/*
371 			 * Behave like the older version of get_device_flags.
372 			 */
373 			size_t max;
374 			/*
375 			 * XXX why skip leading spaces? If an odd INQUIRY
376 			 * value, that should have been part of the
377 			 * scsi_static_device_list[] entry, such as "  FOO"
378 			 * rather than "FOO". Since this code is already
379 			 * here, and we don't know what device it is
380 			 * trying to work with, leave it as-is.
381 			 */
382 			max = 8;	/* max length of vendor */
383 			while ((max > 0) && *vendor == ' ') {
384 				max--;
385 				vendor++;
386 			}
387 			/*
388 			 * XXX removing the following strlen() would be
389 			 * good, using it means that for a an entry not in
390 			 * the list, we scan every byte of every vendor
391 			 * listed in scsi_static_device_list[], and never match
392 			 * a single one (and still have to compare at
393 			 * least the first byte of each vendor).
394 			 */
395 			if (memcmp(devinfo->vendor, vendor,
396 				    min(max, strlen(devinfo->vendor))))
397 				continue;
398 			/*
399 			 * Skip spaces again.
400 			 */
401 			max = 16;	/* max length of model */
402 			while ((max > 0) && *model == ' ') {
403 				max--;
404 				model++;
405 			}
406 			if (memcmp(devinfo->model, model,
407 				   min(max, strlen(devinfo->model))))
408 				continue;
409 			return devinfo->flags;
410 		} else {
411 			if (!memcmp(devinfo->vendor, vendor,
412 				     sizeof(devinfo->vendor)) &&
413 			     !memcmp(devinfo->model, model,
414 				      sizeof(devinfo->model)))
415 				return devinfo->flags;
416 		}
417 	}
418 	return bflags;
419 }
420 
421 #ifdef CONFIG_SCSI_PROC_FS
422 /*
423  * proc_scsi_dev_info_read: dump the scsi_dev_info_list via
424  * /proc/scsi/device_info
425  */
426 static int proc_scsi_devinfo_read(char *buffer, char **start,
427 				  off_t offset, int length)
428 {
429 	struct scsi_dev_info_list *devinfo;
430 	int size, len = 0;
431 	off_t begin = 0;
432 	off_t pos = 0;
433 
434 	list_for_each_entry(devinfo, &scsi_dev_info_list, dev_info_list) {
435 		size = sprintf(buffer + len, "'%.8s' '%.16s' 0x%x\n",
436 			devinfo->vendor, devinfo->model, devinfo->flags);
437 		len += size;
438 		pos = begin + len;
439 		if (pos < offset) {
440 			len = 0;
441 			begin = pos;
442 		}
443 		if (pos > offset + length)
444 			goto stop_output;
445 	}
446 
447 stop_output:
448 	*start = buffer + (offset - begin);	/* Start of wanted data */
449 	len -= (offset - begin);	/* Start slop */
450 	if (len > length)
451 		len = length;	/* Ending slop */
452 	return (len);
453 }
454 
455 /*
456  * proc_scsi_dev_info_write: allow additions to the scsi_dev_info_list via
457  * /proc.
458  *
459  * Use: echo "vendor:model:flag" > /proc/scsi/device_info
460  *
461  * To add a black/white list entry for vendor and model with an integer
462  * value of flag to the scsi device info list.
463  */
464 static int proc_scsi_devinfo_write(struct file *file, const char __user *buf,
465 				   unsigned long length, void *data)
466 {
467 	char *buffer;
468 	int err = length;
469 
470 	if (!buf || length>PAGE_SIZE)
471 		return -EINVAL;
472 	if (!(buffer = (char *) __get_free_page(GFP_KERNEL)))
473 		return -ENOMEM;
474 	if (copy_from_user(buffer, buf, length)) {
475 		err =-EFAULT;
476 		goto out;
477 	}
478 
479 	if (length < PAGE_SIZE)
480 		buffer[length] = '\0';
481 	else if (buffer[PAGE_SIZE-1]) {
482 		err = -EINVAL;
483 		goto out;
484 	}
485 
486 	scsi_dev_info_list_add_str(buffer);
487 
488 out:
489 	free_page((unsigned long)buffer);
490 	return err;
491 }
492 #endif /* CONFIG_SCSI_PROC_FS */
493 
494 module_param_string(dev_flags, scsi_dev_flags, sizeof(scsi_dev_flags), 0);
495 MODULE_PARM_DESC(dev_flags,
496 	 "Given scsi_dev_flags=vendor:model:flags[,v:m:f] add black/white"
497 	 " list entries for vendor and model with an integer value of flags"
498 	 " to the scsi device info list");
499 
500 module_param_named(default_dev_flags, scsi_default_dev_flags, int, S_IRUGO|S_IWUSR);
501 MODULE_PARM_DESC(default_dev_flags,
502 		 "scsi default device flag integer value");
503 
504 /**
505  * scsi_dev_info_list_delete: called from scsi.c:exit_scsi to remove
506  * 	the scsi_dev_info_list.
507  **/
508 void scsi_exit_devinfo(void)
509 {
510 	struct list_head *lh, *lh_next;
511 	struct scsi_dev_info_list *devinfo;
512 
513 #ifdef CONFIG_SCSI_PROC_FS
514 	remove_proc_entry("scsi/device_info", NULL);
515 #endif
516 
517 	list_for_each_safe(lh, lh_next, &scsi_dev_info_list) {
518 		devinfo = list_entry(lh, struct scsi_dev_info_list,
519 				     dev_info_list);
520 		kfree(devinfo);
521 	}
522 }
523 
524 /**
525  * scsi_dev_list_init: set up the dynamic device list.
526  * @dev_list:	string of device flags to add
527  *
528  * Description:
529  * 	Add command line @dev_list entries, then add
530  * 	scsi_static_device_list entries to the scsi device info list.
531  **/
532 int __init scsi_init_devinfo(void)
533 {
534 #ifdef CONFIG_SCSI_PROC_FS
535 	struct proc_dir_entry *p;
536 #endif
537 	int error, i;
538 
539 	error = scsi_dev_info_list_add_str(scsi_dev_flags);
540 	if (error)
541 		return error;
542 
543 	for (i = 0; scsi_static_device_list[i].vendor; i++) {
544 		error = scsi_dev_info_list_add(1 /* compatibile */,
545 				scsi_static_device_list[i].vendor,
546 				scsi_static_device_list[i].model,
547 				NULL,
548 				scsi_static_device_list[i].flags);
549 		if (error)
550 			goto out;
551 	}
552 
553 #ifdef CONFIG_SCSI_PROC_FS
554 	p = create_proc_entry("scsi/device_info", 0, NULL);
555 	if (!p) {
556 		error = -ENOMEM;
557 		goto out;
558 	}
559 
560 	p->owner = THIS_MODULE;
561 	p->get_info = proc_scsi_devinfo_read;
562 	p->write_proc = proc_scsi_devinfo_write;
563 #endif /* CONFIG_SCSI_PROC_FS */
564 
565  out:
566 	if (error)
567 		scsi_exit_devinfo();
568 	return error;
569 }
570