1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * SCSI functions used by both the initiator and the target code. |
4 | */ |
5 | |
6 | #include <linux/bug.h> |
7 | #include <linux/kernel.h> |
8 | #include <linux/string.h> |
9 | #include <linux/errno.h> |
10 | #include <linux/module.h> |
11 | #include <uapi/linux/pr.h> |
12 | #include <asm/unaligned.h> |
13 | #include <scsi/scsi_common.h> |
14 | |
15 | MODULE_LICENSE("GPL v2" ); |
16 | |
17 | /* Command group 3 is reserved and should never be used. */ |
18 | const unsigned char scsi_command_size_tbl[8] = { |
19 | 6, 10, 10, 12, 16, 12, 10, 10 |
20 | }; |
21 | EXPORT_SYMBOL(scsi_command_size_tbl); |
22 | |
23 | /* NB: These are exposed through /proc/scsi/scsi and form part of the ABI. |
24 | * You may not alter any existing entry (although adding new ones is |
25 | * encouraged once assigned by ANSI/INCITS T10). |
26 | */ |
27 | static const char *const scsi_device_types[] = { |
28 | "Direct-Access " , |
29 | "Sequential-Access" , |
30 | "Printer " , |
31 | "Processor " , |
32 | "WORM " , |
33 | "CD-ROM " , |
34 | "Scanner " , |
35 | "Optical Device " , |
36 | "Medium Changer " , |
37 | "Communications " , |
38 | "ASC IT8 " , |
39 | "ASC IT8 " , |
40 | "RAID " , |
41 | "Enclosure " , |
42 | "Direct-Access-RBC" , |
43 | "Optical card " , |
44 | "Bridge controller" , |
45 | "Object storage " , |
46 | "Automation/Drive " , |
47 | "Security Manager " , |
48 | "Direct-Access-ZBC" , |
49 | }; |
50 | |
51 | /** |
52 | * scsi_device_type - Return 17-char string indicating device type. |
53 | * @type: type number to look up |
54 | */ |
55 | const char *scsi_device_type(unsigned type) |
56 | { |
57 | if (type == 0x1e) |
58 | return "Well-known LUN " ; |
59 | if (type == 0x1f) |
60 | return "No Device " ; |
61 | if (type >= ARRAY_SIZE(scsi_device_types)) |
62 | return "Unknown " ; |
63 | return scsi_device_types[type]; |
64 | } |
65 | EXPORT_SYMBOL(scsi_device_type); |
66 | |
67 | enum pr_type scsi_pr_type_to_block(enum scsi_pr_type type) |
68 | { |
69 | switch (type) { |
70 | case SCSI_PR_WRITE_EXCLUSIVE: |
71 | return PR_WRITE_EXCLUSIVE; |
72 | case SCSI_PR_EXCLUSIVE_ACCESS: |
73 | return PR_EXCLUSIVE_ACCESS; |
74 | case SCSI_PR_WRITE_EXCLUSIVE_REG_ONLY: |
75 | return PR_WRITE_EXCLUSIVE_REG_ONLY; |
76 | case SCSI_PR_EXCLUSIVE_ACCESS_REG_ONLY: |
77 | return PR_EXCLUSIVE_ACCESS_REG_ONLY; |
78 | case SCSI_PR_WRITE_EXCLUSIVE_ALL_REGS: |
79 | return PR_WRITE_EXCLUSIVE_ALL_REGS; |
80 | case SCSI_PR_EXCLUSIVE_ACCESS_ALL_REGS: |
81 | return PR_EXCLUSIVE_ACCESS_ALL_REGS; |
82 | } |
83 | |
84 | return 0; |
85 | } |
86 | EXPORT_SYMBOL_GPL(scsi_pr_type_to_block); |
87 | |
88 | enum scsi_pr_type block_pr_type_to_scsi(enum pr_type type) |
89 | { |
90 | switch (type) { |
91 | case PR_WRITE_EXCLUSIVE: |
92 | return SCSI_PR_WRITE_EXCLUSIVE; |
93 | case PR_EXCLUSIVE_ACCESS: |
94 | return SCSI_PR_EXCLUSIVE_ACCESS; |
95 | case PR_WRITE_EXCLUSIVE_REG_ONLY: |
96 | return SCSI_PR_WRITE_EXCLUSIVE_REG_ONLY; |
97 | case PR_EXCLUSIVE_ACCESS_REG_ONLY: |
98 | return SCSI_PR_EXCLUSIVE_ACCESS_REG_ONLY; |
99 | case PR_WRITE_EXCLUSIVE_ALL_REGS: |
100 | return SCSI_PR_WRITE_EXCLUSIVE_ALL_REGS; |
101 | case PR_EXCLUSIVE_ACCESS_ALL_REGS: |
102 | return SCSI_PR_EXCLUSIVE_ACCESS_ALL_REGS; |
103 | } |
104 | |
105 | return 0; |
106 | } |
107 | EXPORT_SYMBOL_GPL(block_pr_type_to_scsi); |
108 | |
109 | /** |
110 | * scsilun_to_int - convert a scsi_lun to an int |
111 | * @scsilun: struct scsi_lun to be converted. |
112 | * |
113 | * Description: |
114 | * Convert @scsilun from a struct scsi_lun to a four-byte host byte-ordered |
115 | * integer, and return the result. The caller must check for |
116 | * truncation before using this function. |
117 | * |
118 | * Notes: |
119 | * For a description of the LUN format, post SCSI-3 see the SCSI |
120 | * Architecture Model, for SCSI-3 see the SCSI Controller Commands. |
121 | * |
122 | * Given a struct scsi_lun of: d2 04 0b 03 00 00 00 00, this function |
123 | * returns the integer: 0x0b03d204 |
124 | * |
125 | * This encoding will return a standard integer LUN for LUNs smaller |
126 | * than 256, which typically use a single level LUN structure with |
127 | * addressing method 0. |
128 | */ |
129 | u64 scsilun_to_int(struct scsi_lun *scsilun) |
130 | { |
131 | int i; |
132 | u64 lun; |
133 | |
134 | lun = 0; |
135 | for (i = 0; i < sizeof(lun); i += 2) |
136 | lun = lun | (((u64)scsilun->scsi_lun[i] << ((i + 1) * 8)) | |
137 | ((u64)scsilun->scsi_lun[i + 1] << (i * 8))); |
138 | return lun; |
139 | } |
140 | EXPORT_SYMBOL(scsilun_to_int); |
141 | |
142 | /** |
143 | * int_to_scsilun - reverts an int into a scsi_lun |
144 | * @lun: integer to be reverted |
145 | * @scsilun: struct scsi_lun to be set. |
146 | * |
147 | * Description: |
148 | * Reverts the functionality of the scsilun_to_int, which packed |
149 | * an 8-byte lun value into an int. This routine unpacks the int |
150 | * back into the lun value. |
151 | * |
152 | * Notes: |
153 | * Given an integer : 0x0b03d204, this function returns a |
154 | * struct scsi_lun of: d2 04 0b 03 00 00 00 00 |
155 | * |
156 | */ |
157 | void int_to_scsilun(u64 lun, struct scsi_lun *scsilun) |
158 | { |
159 | int i; |
160 | |
161 | memset(scsilun->scsi_lun, 0, sizeof(scsilun->scsi_lun)); |
162 | |
163 | for (i = 0; i < sizeof(lun); i += 2) { |
164 | scsilun->scsi_lun[i] = (lun >> 8) & 0xFF; |
165 | scsilun->scsi_lun[i+1] = lun & 0xFF; |
166 | lun = lun >> 16; |
167 | } |
168 | } |
169 | EXPORT_SYMBOL(int_to_scsilun); |
170 | |
171 | /** |
172 | * scsi_normalize_sense - normalize main elements from either fixed or |
173 | * descriptor sense data format into a common format. |
174 | * |
175 | * @sense_buffer: byte array containing sense data returned by device |
176 | * @sb_len: number of valid bytes in sense_buffer |
177 | * @sshdr: pointer to instance of structure that common |
178 | * elements are written to. |
179 | * |
180 | * Notes: |
181 | * The "main elements" from sense data are: response_code, sense_key, |
182 | * asc, ascq and additional_length (only for descriptor format). |
183 | * |
184 | * Typically this function can be called after a device has |
185 | * responded to a SCSI command with the CHECK_CONDITION status. |
186 | * |
187 | * Return value: |
188 | * true if valid sense data information found, else false; |
189 | */ |
190 | bool scsi_normalize_sense(const u8 *sense_buffer, int sb_len, |
191 | struct scsi_sense_hdr *sshdr) |
192 | { |
193 | memset(sshdr, 0, sizeof(struct scsi_sense_hdr)); |
194 | |
195 | if (!sense_buffer || !sb_len) |
196 | return false; |
197 | |
198 | sshdr->response_code = (sense_buffer[0] & 0x7f); |
199 | |
200 | if (!scsi_sense_valid(sshdr)) |
201 | return false; |
202 | |
203 | if (sshdr->response_code >= 0x72) { |
204 | /* |
205 | * descriptor format |
206 | */ |
207 | if (sb_len > 1) |
208 | sshdr->sense_key = (sense_buffer[1] & 0xf); |
209 | if (sb_len > 2) |
210 | sshdr->asc = sense_buffer[2]; |
211 | if (sb_len > 3) |
212 | sshdr->ascq = sense_buffer[3]; |
213 | if (sb_len > 7) |
214 | sshdr->additional_length = sense_buffer[7]; |
215 | } else { |
216 | /* |
217 | * fixed format |
218 | */ |
219 | if (sb_len > 2) |
220 | sshdr->sense_key = (sense_buffer[2] & 0xf); |
221 | if (sb_len > 7) { |
222 | sb_len = min(sb_len, sense_buffer[7] + 8); |
223 | if (sb_len > 12) |
224 | sshdr->asc = sense_buffer[12]; |
225 | if (sb_len > 13) |
226 | sshdr->ascq = sense_buffer[13]; |
227 | } |
228 | } |
229 | |
230 | return true; |
231 | } |
232 | EXPORT_SYMBOL(scsi_normalize_sense); |
233 | |
234 | /** |
235 | * scsi_sense_desc_find - search for a given descriptor type in descriptor sense data format. |
236 | * @sense_buffer: byte array of descriptor format sense data |
237 | * @sb_len: number of valid bytes in sense_buffer |
238 | * @desc_type: value of descriptor type to find |
239 | * (e.g. 0 -> information) |
240 | * |
241 | * Notes: |
242 | * only valid when sense data is in descriptor format |
243 | * |
244 | * Return value: |
245 | * pointer to start of (first) descriptor if found else NULL |
246 | */ |
247 | const u8 * scsi_sense_desc_find(const u8 * sense_buffer, int sb_len, |
248 | int desc_type) |
249 | { |
250 | int add_sen_len, add_len, desc_len, k; |
251 | const u8 * descp; |
252 | |
253 | if ((sb_len < 8) || (0 == (add_sen_len = sense_buffer[7]))) |
254 | return NULL; |
255 | if ((sense_buffer[0] < 0x72) || (sense_buffer[0] > 0x73)) |
256 | return NULL; |
257 | add_sen_len = (add_sen_len < (sb_len - 8)) ? |
258 | add_sen_len : (sb_len - 8); |
259 | descp = &sense_buffer[8]; |
260 | for (desc_len = 0, k = 0; k < add_sen_len; k += desc_len) { |
261 | descp += desc_len; |
262 | add_len = (k < (add_sen_len - 1)) ? descp[1]: -1; |
263 | desc_len = add_len + 2; |
264 | if (descp[0] == desc_type) |
265 | return descp; |
266 | if (add_len < 0) // short descriptor ?? |
267 | break; |
268 | } |
269 | return NULL; |
270 | } |
271 | EXPORT_SYMBOL(scsi_sense_desc_find); |
272 | |
273 | /** |
274 | * scsi_build_sense_buffer - build sense data in a buffer |
275 | * @desc: Sense format (non-zero == descriptor format, |
276 | * 0 == fixed format) |
277 | * @buf: Where to build sense data |
278 | * @key: Sense key |
279 | * @asc: Additional sense code |
280 | * @ascq: Additional sense code qualifier |
281 | * |
282 | **/ |
283 | void scsi_build_sense_buffer(int desc, u8 *buf, u8 key, u8 asc, u8 ascq) |
284 | { |
285 | if (desc) { |
286 | buf[0] = 0x72; /* descriptor, current */ |
287 | buf[1] = key; |
288 | buf[2] = asc; |
289 | buf[3] = ascq; |
290 | buf[7] = 0; |
291 | } else { |
292 | buf[0] = 0x70; /* fixed, current */ |
293 | buf[2] = key; |
294 | buf[7] = 0xa; |
295 | buf[12] = asc; |
296 | buf[13] = ascq; |
297 | } |
298 | } |
299 | EXPORT_SYMBOL(scsi_build_sense_buffer); |
300 | |
301 | /** |
302 | * scsi_set_sense_information - set the information field in a |
303 | * formatted sense data buffer |
304 | * @buf: Where to build sense data |
305 | * @buf_len: buffer length |
306 | * @info: 64-bit information value to be set |
307 | * |
308 | * Return value: |
309 | * 0 on success or -EINVAL for invalid sense buffer length |
310 | **/ |
311 | int scsi_set_sense_information(u8 *buf, int buf_len, u64 info) |
312 | { |
313 | if ((buf[0] & 0x7f) == 0x72) { |
314 | u8 *ucp, len; |
315 | |
316 | len = buf[7]; |
317 | ucp = (char *)scsi_sense_desc_find(buf, len + 8, 0); |
318 | if (!ucp) { |
319 | buf[7] = len + 0xc; |
320 | ucp = buf + 8 + len; |
321 | } |
322 | |
323 | if (buf_len < len + 0xc) |
324 | /* Not enough room for info */ |
325 | return -EINVAL; |
326 | |
327 | ucp[0] = 0; |
328 | ucp[1] = 0xa; |
329 | ucp[2] = 0x80; /* Valid bit */ |
330 | ucp[3] = 0; |
331 | put_unaligned_be64(val: info, p: &ucp[4]); |
332 | } else if ((buf[0] & 0x7f) == 0x70) { |
333 | /* |
334 | * Only set the 'VALID' bit if we can represent the value |
335 | * correctly; otherwise just fill out the lower bytes and |
336 | * clear the 'VALID' flag. |
337 | */ |
338 | if (info <= 0xffffffffUL) |
339 | buf[0] |= 0x80; |
340 | else |
341 | buf[0] &= 0x7f; |
342 | put_unaligned_be32(val: (u32)info, p: &buf[3]); |
343 | } |
344 | |
345 | return 0; |
346 | } |
347 | EXPORT_SYMBOL(scsi_set_sense_information); |
348 | |
349 | /** |
350 | * scsi_set_sense_field_pointer - set the field pointer sense key |
351 | * specific information in a formatted sense data buffer |
352 | * @buf: Where to build sense data |
353 | * @buf_len: buffer length |
354 | * @fp: field pointer to be set |
355 | * @bp: bit pointer to be set |
356 | * @cd: command/data bit |
357 | * |
358 | * Return value: |
359 | * 0 on success or -EINVAL for invalid sense buffer length |
360 | */ |
361 | int scsi_set_sense_field_pointer(u8 *buf, int buf_len, u16 fp, u8 bp, bool cd) |
362 | { |
363 | u8 *ucp, len; |
364 | |
365 | if ((buf[0] & 0x7f) == 0x72) { |
366 | len = buf[7]; |
367 | ucp = (char *)scsi_sense_desc_find(buf, len + 8, 2); |
368 | if (!ucp) { |
369 | buf[7] = len + 8; |
370 | ucp = buf + 8 + len; |
371 | } |
372 | |
373 | if (buf_len < len + 8) |
374 | /* Not enough room for info */ |
375 | return -EINVAL; |
376 | |
377 | ucp[0] = 2; |
378 | ucp[1] = 6; |
379 | ucp[4] = 0x80; /* Valid bit */ |
380 | if (cd) |
381 | ucp[4] |= 0x40; |
382 | if (bp < 0x8) |
383 | ucp[4] |= 0x8 | bp; |
384 | put_unaligned_be16(val: fp, p: &ucp[5]); |
385 | } else if ((buf[0] & 0x7f) == 0x70) { |
386 | len = buf[7]; |
387 | if (len < 18) |
388 | buf[7] = 18; |
389 | |
390 | buf[15] = 0x80; |
391 | if (cd) |
392 | buf[15] |= 0x40; |
393 | if (bp < 0x8) |
394 | buf[15] |= 0x8 | bp; |
395 | put_unaligned_be16(val: fp, p: &buf[16]); |
396 | } |
397 | |
398 | return 0; |
399 | } |
400 | EXPORT_SYMBOL(scsi_set_sense_field_pointer); |
401 | |