2 .\" Copyright (c) 1998 Kenneth D. Merry.
3 .\" All rights reserved.
5 .\" Redistribution and use in source and binary forms, with or without
6 .\" modification, are permitted provided that the following conditions
8 .\" 1. Redistributions of source code must retain the above copyright
9 .\" notice, this list of conditions and the following disclaimer.
10 .\" 2. Redistributions in binary form must reproduce the above copyright
11 .\" notice, this list of conditions and the following disclaimer in the
12 .\" documentation and/or other materials provided with the distribution.
13 .\" 3. The name of the author may not be used to endorse or promote products
14 .\" derived from this software without specific prior written permission.
16 .\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 .\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 .\" This man page borrows heavily from the old scsi(3) man page, which had
31 .\" the following copyright:
33 .\" Copyright (c) 1994 HD Associates (hd@world.std.com)
34 .\" All rights reserved.
36 .\" Redistribution and use in source and binary forms, with or without
37 .\" modification, are permitted provided that the following conditions
39 .\" 1. Redistributions of source code must retain the above copyright
40 .\" notice, this list of conditions and the following disclaimer.
41 .\" 2. Redistributions in binary form must reproduce the above copyright
42 .\" notice, this list of conditions and the following disclaimer in the
43 .\" documentation and/or other materials provided with the distribution.
44 .\" 3. All advertising materials mentioning features or use of this software
45 .\" must display the following acknowledgement:
46 .\" This product includes software developed by HD Associates
47 .\" 4. Neither the name of the HD Associates nor the names of its contributors
48 .\" may be used to endorse or promote products derived from this software
49 .\" without specific prior written permission.
51 .\" THIS SOFTWARE IS PROVIDED BY HD ASSOCIATES``AS IS'' AND
52 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
53 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
54 .\" ARE DISCLAIMED. IN NO EVENT SHALL HD ASSOCIATES OR CONTRIBUTORS BE LIABLE
55 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
56 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
57 .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
58 .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
59 .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
60 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
69 .Nm csio_build_visit ,
71 .Nm csio_decode_visit ,
73 .Nm buff_decode_visit ,
75 .Nm csio_encode_visit ,
77 .Nd CAM user library SCSI buffer parsing routines
85 .Fa "struct ccb_scsiio *csio"
86 .Fa "uint8_t *data_ptr"
87 .Fa "uint32_t dxfer_len"
91 .Fa "const char *cmd_spec"
96 .Fa "struct ccb_scsiio *csio"
97 .Fa "uint8_t *data_ptr"
98 .Fa "uint32_t dxfer_len"
100 .Fa "int retry_count"
102 .Fa "const char *cmd_spec"
103 .Fa "int (*arg_get)(void *hook, char *field_name)"
108 .Fa "struct ccb_scsiio *csio"
109 .Fa "const char *fmt"
113 .Fo csio_decode_visit
114 .Fa "struct ccb_scsiio *csio"
115 .Fa "const char *fmt"
116 .Fa "void (*arg_put)(void *hook"
127 .Fa "const char *fmt"
131 .Fo buff_decode_visit
134 .Fa "const char *fmt"
135 .Fa "void (*arg_put)(void *, int, void *, int, char *)"
140 .Fa "struct ccb_scsiio *csio"
141 .Fa "const char *fmt"
145 .Fo csio_encode_visit
146 .Fa "struct ccb_scsiio *csio"
147 .Fa "const char *fmt"
148 .Fa "int (*arg_get)(void *hook, char *field_name)"
152 .Fo buff_encode_visit
155 .Fa "const char *fmt"
156 .Fa "int (*arg_get)(void *hook, char *field_name)"
160 The CAM buffer/CDB encoding and decoding routines provide a relatively easy
161 migration path for userland
163 applications written with the similarly-named
165 functions from the old
170 These functions may be used in new applications, but users may find it
171 easier to use the various SCSI CCB building functions included with the
175 .Fn scsi_start_stop ,
177 .Fn scsi_read_write .
182 structure based on the information provided in
183 the variable argument list.
184 It gracefully handles a NULL
186 argument passed to it.
189 is the length of the data phase; the data transfer direction is
195 is the data buffer used during the
201 command in question, this should be set to NULL.
203 transfer for the command, this buffer must be at least
208 are the flags defined in
211 /* Common CCB header */
214 CAM_CDB_POINTER = 0x00000001,/* The CDB field is a pointer */
215 CAM_SCATTER_VALID = 0x00000010,/* Scatter/gather list is valid */
216 CAM_DIS_AUTOSENSE = 0x00000020,/* Disable autosense feature */
217 CAM_DIR_RESV = 0x00000000,/* Data direction (00:reserved) */
218 CAM_DIR_IN = 0x00000040,/* Data direction (01:DATA IN) */
219 CAM_DIR_OUT = 0x00000080,/* Data direction (10:DATA OUT) */
220 CAM_DIR_NONE = 0x000000C0,/* Data direction (11:no data) */
221 CAM_DIR_MASK = 0x000000C0,/* Data direction Mask */
222 CAM_DEV_QFRZDIS = 0x00000400,/* Disable DEV Q freezing */
223 CAM_DEV_QFREEZE = 0x00000800,/* Freeze DEV Q on execution */
224 CAM_HIGH_POWER = 0x00001000,/* Command takes a lot of power */
225 CAM_SENSE_PTR = 0x00002000,/* Sense data is a pointer */
226 CAM_SENSE_PHYS = 0x00004000,/* Sense pointer is physical addr*/
227 CAM_TAG_ACTION_VALID = 0x00008000,/* Use the tag action in this ccb*/
228 CAM_PASS_ERR_RECOVER = 0x00010000,/* Pass driver does err. recovery*/
229 CAM_DIS_DISCONNECT = 0x00020000,/* Disable disconnect */
230 CAM_SG_LIST_PHYS = 0x00040000,/* SG list has physical addrs. */
231 CAM_DATA_PHYS = 0x00200000,/* SG/Buffer data ptrs are phys. */
232 CAM_CDB_PHYS = 0x00400000,/* CDB pointer is physical */
234 /* Host target Mode flags */
235 CAM_SEND_SENSE = 0x08000000,/* Send sense data with status */
236 CAM_SEND_STATUS = 0x80000000,/* Send status after data phase */
240 Multiple flags should be ORed together.
241 Any of the CCB flags may be used,
242 although it is worth noting several important ones here:
243 .Bl -tag -width CAM_PASS_ERR_RECOVER
245 This indicates that the operation in question is a read operation.
247 data is being read from the
249 device to the user-supplied buffer.
251 This indicates that the operation is a write operation.
253 written from the user-supplied buffer to the device.
255 This indicates that there is no data to be transferred for this command.
256 .It Dv CAM_DEV_QFRZDIS
257 This flag disables device queue freezing as an error recovery mechanism.
258 .It Dv CAM_PASS_ERR_RECOVER
261 driver to enable error recovery.
262 The default is to not perform error
263 recovery, which means that the retry count will not be honored without this
264 flag, among other things.
266 This indicates that the address contained in
268 is a physical address, not a virtual address.
273 tells the kernel how many times to retry the command in question.
275 retry count is ignored unless the
277 driver is told to enable error recovery via the
278 .Dv CAM_PASS_ERR_RECOVER
283 tells the kernel how long to wait for the given command to complete.
285 the timeout expires and the command has not completed, the CCB will be
286 returned from the kernel with an appropriate error status.
289 is a CDB format specifier used to build up the SCSI CDB.
290 This text string is made up of a list of field specifiers.
292 specifiers specify the value for each CDB field (including indicating
293 that the value be taken from the next argument in the
294 variable argument list), the width
295 of the field in bits or bytes, and an optional name.
297 ignored, and the pound sign ('#') introduces a comment that ends at the
298 end of the current line.
300 The optional name is the first part of a field specifier and
302 The text in curly braces in this example are
304 .Dl "{PS} v:b1 {Reserved} 0:b1 {Page Code} v:b6 # Mode select page"
306 This field specifier has two one bit fields and one six bit field.
307 The second one bit field is the constant value 0 and the first
308 one bit field and the six bit field are taken from the variable
310 Multi byte fields are swapped into the SCSI byte order in the
311 CDB and white space is ignored.
313 When the field is a hex value or the letter v, (e.g.,
317 then a single byte value
318 is copied to the next unused byte of the CDB.
321 is used the next integer argument is taken from the variable argument list
324 A constant hex value followed by a field width specifier or the letter
326 followed by a field width specifier (e.g.,
331 specifies a field of a given bit or byte width.
332 Either the constant value or (for the V specifier) the next integer value from
333 the variable argument list is copied to the next unused
334 bits or bytes of the CDB.
336 A decimal number or the letter
338 followed by a decimal number field width indicates a bit field of that width.
339 The bit fields are packed as tightly as possible beginning with the
340 high bit (so that it reads the same as the SCSI spec), and a new byte of
341 the CDB is started whenever a byte fills completely or when an
343 field is encountered.
345 A field width specifier consisting of the letter
348 1, 2, 3 or 4 indicates a 1, 2, 3 or 4 byte integral value that must
349 be swapped into SCSI byte order (MSB first).
353 field specifier the next integer argument is taken from the variable argument
354 list and that value is used swapped into SCSI byte order.
357 operates similarly to
359 except that the values to substitute for variable arguments in
361 are retrieved via the
363 function passed in to
369 function takes two arguments:
370 .Bl -tag -width field_name
374 function at each invocation.
377 function to keep some state in between calls without using global or static
380 is the field name supplied in
386 is used to decode information from the data in phase of the SCSI
389 The decoding is similar to
390 the command specifier processing of
392 except that the data is extracted from the data pointed to by
394 The stdarg list should be pointers to integers instead of integer
396 A seek field type and a suppression modifier are added.
399 suppression modifier (e.g.,
403 suppresses assignment from the field and can be used to skip
404 over bytes or bits in the data, without having to copy
405 them to a dummy variable in the arg list.
409 permits you to skip over data.
410 This seeks to an absolute position
412 or a relative position
414 in the data, based on whether or not the presence of the '+' sign.
415 The seek value can be specified as
417 and the next integer value from the argument list will be
418 used as the seek value.
420 .Fn csio_decode_visit
423 except that instead of placing the decoded contents of the buffer in
424 variadic arguments, the decoded buffer contents are returned to the user
427 function that is passed in.
430 function takes several arguments:
431 .Bl -tag -width letter
433 The "hook" is a mechanism to allow the
435 function to save state in between calls.
437 is the letter describing the format of the argument being passed into the
440 is a void pointer to the value being passed into the function.
442 is the size of the value being passed into the
445 The argument format determines the unit of measure.
447 This is a text description of the field, if one was provided in the
452 decodes an arbitrary data buffer using the method
456 .Fn buff_decode_visit
457 decodes an arbitrary data buffer using the method described above for
458 .Fn csio_decode_visit .
463 portion (not the CDB!) of a
465 structure, using the method described above for
468 .Fn csio_encode_visit
471 portion (not the CDB!) of a
473 structure, using the method described above for
474 .Fn csio_build_visit .
476 .Fn buff_encode_visit
477 encodes an arbitrary data pointer, using the method described
479 .Fn csio_build_visit .
482 .Fn csio_build_visit ,
484 .Fn csio_encode_visit ,
486 .Fn buff_encode_visit
487 return the number of fields processed.
490 .Fn csio_decode_visit ,
493 .Fn buff_decode_visit
494 return the number of assignments performed.
500 The CAM versions of these functions are based upon similar functions
501 implemented for the old
505 The encoding/decoding functions in the old
508 .An Peter Dufault Aq Mt dufault@hda.com .
510 Many systems have comparable interfaces to permit a user to construct a
511 SCSI command in user space.
515 data structure was almost identical to the SGI /dev/scsi data structure.
516 If anyone knows the name of the authors it should go here;
518 first read about it in a 1989 Sun Expert magazine.
520 The new CCB data structures are derived from the CAM-2 and CAM-3
524 implemented a clone of SGI's interface in
530 library and the related kernel ioctl.
531 If anyone needs that for compatibility, contact
532 .Mt dufault@hda.com .
535 .An Kenneth Merry Aq Mt ken@FreeBSD.org
536 implemented the CAM versions of these encoding and decoding functions.
537 This current work is based upon earlier work by
538 .An Peter Dufault Aq Mt dufault@hda.com .
540 There should probably be a function that encodes both the CDB and the data
544 I discovered this while implementing the arbitrary command execution
547 but I have not yet had time to implement such a function.
549 Some of the CCB flag descriptions really do not belong here.
551 belong in a generic CCB man page.
552 Since that man page has not yet been
553 written, the shorter descriptions here will have to suffice.