2 * compose persistent device path
4 * Copyright (C) 2009-2011 Kay Sievers <kay.sievers@vrfy.org>
6 * Logic based on Hannes Reinecke's shell script.
8 * This program is free software: you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation, either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program. If not, see <http://www.gnu.org/licenses/>.
35 static int path_prepend(char **path
, const char *fmt
, ...)
42 err
= vasprintf(&pre
, fmt
, va
);
50 err
= asprintf(&new, "%s-%s", pre
, *path
);
64 ** Linux only supports 32 bit luns.
65 ** See drivers/scsi/scsi_scan.c::scsilun_to_int() for more details.
67 static int format_lun_number(struct udev_device
*dev
, char **path
)
69 unsigned long lun
= strtoul(udev_device_get_sysnum(dev
), NULL
, 10);
71 /* address method 0, peripheral device addressing with bus id of zero */
73 return path_prepend(path
, "lun-%d", lun
);
74 /* handle all other lun addressing methods by using a variant of the original lun format */
75 return path_prepend(path
, "lun-0x%04x%04x00000000", (lun
& 0xffff), (lun
>> 16) & 0xffff);
78 static struct udev_device
*skip_subsystem(struct udev_device
*dev
, const char *subsys
)
80 struct udev_device
*parent
= dev
;
82 while (parent
!= NULL
) {
83 const char *subsystem
;
85 subsystem
= udev_device_get_subsystem(parent
);
86 if (subsystem
== NULL
|| strcmp(subsystem
, subsys
) != 0)
89 parent
= udev_device_get_parent(parent
);
94 static struct udev_device
*handle_scsi_fibre_channel(struct udev_device
*parent
, char **path
)
96 struct udev
*udev
= udev_device_get_udev(parent
);
97 struct udev_device
*targetdev
;
98 struct udev_device
*fcdev
= NULL
;
102 targetdev
= udev_device_get_parent_with_subsystem_devtype(parent
, "scsi", "scsi_target");
103 if (targetdev
== NULL
)
106 fcdev
= udev_device_new_from_subsystem_sysname(udev
, "fc_transport", udev_device_get_sysname(targetdev
));
109 port
= udev_device_get_sysattr_value(fcdev
, "port_name");
115 format_lun_number(parent
, &lun
);
116 path_prepend(path
, "fc-%s-%s", port
, lun
);
120 udev_device_unref(fcdev
);
124 static struct udev_device
*handle_scsi_sas(struct udev_device
*parent
, char **path
)
126 struct udev
*udev
= udev_device_get_udev(parent
);
127 struct udev_device
*targetdev
;
128 struct udev_device
*target_parent
;
129 struct udev_device
*sasdev
;
130 const char *sas_address
;
133 targetdev
= udev_device_get_parent_with_subsystem_devtype(parent
, "scsi", "scsi_target");
134 if (targetdev
== NULL
)
137 target_parent
= udev_device_get_parent(targetdev
);
138 if (target_parent
== NULL
)
141 sasdev
= udev_device_new_from_subsystem_sysname(udev
, "sas_device",
142 udev_device_get_sysname(target_parent
));
146 sas_address
= udev_device_get_sysattr_value(sasdev
, "sas_address");
147 if (sas_address
== NULL
) {
152 format_lun_number(parent
, &lun
);
153 path_prepend(path
, "sas-%s-%s", sas_address
, lun
);
157 udev_device_unref(sasdev
);
161 static struct udev_device
*handle_scsi_iscsi(struct udev_device
*parent
, char **path
)
163 struct udev
*udev
= udev_device_get_udev(parent
);
164 struct udev_device
*transportdev
;
165 struct udev_device
*sessiondev
= NULL
;
168 struct udev_device
*conndev
= NULL
;
173 /* find iscsi session */
174 transportdev
= parent
;
176 transportdev
= udev_device_get_parent(transportdev
);
177 if (transportdev
== NULL
)
179 if (strncmp(udev_device_get_sysname(transportdev
), "session", 7) == 0)
183 /* find iscsi session device */
184 sessiondev
= udev_device_new_from_subsystem_sysname(udev
, "iscsi_session", udev_device_get_sysname(transportdev
));
185 if (sessiondev
== NULL
)
187 target
= udev_device_get_sysattr_value(sessiondev
, "targetname");
188 if (target
== NULL
) {
193 if (asprintf(&connname
, "connection%s:0", udev_device_get_sysnum(transportdev
)) < 0) {
197 conndev
= udev_device_new_from_subsystem_sysname(udev
, "iscsi_connection", connname
);
199 if (conndev
== NULL
) {
203 addr
= udev_device_get_sysattr_value(conndev
, "persistent_address");
204 port
= udev_device_get_sysattr_value(conndev
, "persistent_port");
205 if (addr
== NULL
|| port
== NULL
) {
210 format_lun_number(parent
, &lun
);
211 path_prepend(path
, "ip-%s:%s-iscsi-%s-%s", addr
, port
, target
, lun
);
215 udev_device_unref(sessiondev
);
216 udev_device_unref(conndev
);
220 static struct udev_device
*handle_scsi_default(struct udev_device
*parent
, char **path
)
222 struct udev_device
*hostdev
;
223 int host
, bus
, target
, lun
;
231 hostdev
= udev_device_get_parent_with_subsystem_devtype(parent
, "scsi", "scsi_host");
235 name
= udev_device_get_sysname(parent
);
236 if (sscanf(name
, "%d:%d:%d:%d", &host
, &bus
, &target
, &lun
) != 4)
239 /* rebase host offset to get the local relative number */
241 base
= strdup(udev_device_get_syspath(hostdev
));
244 pos
= strrchr(base
, '/');
255 for (dent
= readdir(dir
); dent
!= NULL
; dent
= readdir(dir
)) {
259 if (dent
->d_name
[0] == '.')
261 if (dent
->d_type
!= DT_DIR
&& dent
->d_type
!= DT_LNK
)
263 if (strncmp(dent
->d_name
, "host", 4) != 0)
265 i
= strtoul(&dent
->d_name
[4], &rest
, 10);
269 * find the smallest number; the host really needs to export its
270 * own instance number per parent device; relying on the global host
271 * enumeration and plainly rebasing the numbers sounds unreliable
273 if (basenum
== -1 || i
< basenum
)
283 path_prepend(path
, "scsi-%u:%u:%u:%u", host
, bus
, target
, lun
);
289 static struct udev_device
*handle_scsi(struct udev_device
*parent
, char **path
)
295 devtype
= udev_device_get_devtype(parent
);
296 if (devtype
== NULL
|| strcmp(devtype
, "scsi_device") != 0)
300 id
= udev_device_get_sysattr_value(parent
, "ieee1394_id");
302 parent
= skip_subsystem(parent
, "scsi");
303 path_prepend(path
, "ieee1394-0x%s", id
);
307 /* lousy scsi sysfs does not have a "subsystem" for the transport */
308 name
= udev_device_get_syspath(parent
);
310 if (strstr(name
, "/rport-") != NULL
) {
311 parent
= handle_scsi_fibre_channel(parent
, path
);
315 if (strstr(name
, "/end_device-") != NULL
) {
316 parent
= handle_scsi_sas(parent
, path
);
320 if (strstr(name
, "/session") != NULL
) {
321 parent
= handle_scsi_iscsi(parent
, path
);
326 * We do not support the ATA transport class, it creates duplicated link
327 * names as the fake SCSI host adapters are all separated, they are all
328 * re-based as host == 0. ATA should just stop faking two duplicated
329 * hierarchies for a single topology and leave the SCSI stuff alone;
330 * until that happens, there are no by-path/ links for ATA devices behind
331 * an ATA transport class.
333 if (strstr(name
, "/ata") != NULL
) {
338 parent
= handle_scsi_default(parent
, path
);
343 static void handle_scsi_tape(struct udev_device
*dev
, char **path
)
347 /* must be the last device in the syspath */
351 name
= udev_device_get_sysname(dev
);
352 if (strncmp(name
, "nst", 3) == 0 && strchr("lma", name
[3]) != NULL
)
353 path_prepend(path
, "nst%c", name
[3]);
354 else if (strncmp(name
, "st", 2) == 0 && strchr("lma", name
[2]) != NULL
)
355 path_prepend(path
, "st%c", name
[2]);
358 static struct udev_device
*handle_usb(struct udev_device
*parent
, char **path
)
364 devtype
= udev_device_get_devtype(parent
);
367 if (strcmp(devtype
, "usb_interface") != 0 && strcmp(devtype
, "usb_device") != 0)
370 str
= udev_device_get_sysname(parent
);
371 port
= strchr(str
, '-');
376 parent
= skip_subsystem(parent
, "usb");
377 path_prepend(path
, "usb-0:%s", port
);
381 static struct udev_device
*handle_ccw(struct udev_device
*parent
, struct udev_device
*dev
, char **path
)
383 struct udev_device
*scsi_dev
;
385 scsi_dev
= udev_device_get_parent_with_subsystem_devtype(dev
, "scsi", "scsi_device");
386 if (scsi_dev
!= NULL
) {
391 hba_id
= udev_device_get_sysattr_value(scsi_dev
, "hba_id");
392 wwpn
= udev_device_get_sysattr_value(scsi_dev
, "wwpn");
393 lun
= udev_device_get_sysattr_value(scsi_dev
, "fcp_lun");
394 if (hba_id
!= NULL
&& lun
!= NULL
&& wwpn
!= NULL
) {
395 path_prepend(path
, "ccw-%s-zfcp-%s:%s", hba_id
, wwpn
, lun
);
400 path_prepend(path
, "ccw-%s", udev_device_get_sysname(parent
));
402 parent
= skip_subsystem(parent
, "ccw");
406 static int builtin_path_id(struct udev_device
*dev
, int argc
, char *argv
[], bool test
)
408 struct udev_device
*parent
;
412 parent
= udev_device_get_parent_with_subsystem_devtype(dev
, "ccw", NULL
);
413 if (parent
!= NULL
) {
414 handle_ccw(parent
, dev
, &path
);
418 /* walk up the chain of devices and compose path */
420 while (parent
!= NULL
) {
423 subsys
= udev_device_get_subsystem(parent
);
424 if (subsys
== NULL
) {
426 } else if (strcmp(subsys
, "scsi_tape") == 0) {
427 handle_scsi_tape(parent
, &path
);
428 } else if (strcmp(subsys
, "scsi") == 0) {
429 parent
= handle_scsi(parent
, &path
);
430 } else if (strcmp(subsys
, "usb") == 0) {
431 parent
= handle_usb(parent
, &path
);
432 } else if (strcmp(subsys
, "serio") == 0) {
433 path_prepend(&path
, "serio-%s", udev_device_get_sysnum(parent
));
434 parent
= skip_subsystem(parent
, "serio");
435 } else if (strcmp(subsys
, "pci") == 0) {
436 path_prepend(&path
, "pci-%s", udev_device_get_sysname(parent
));
437 parent
= skip_subsystem(parent
, "pci");
438 } else if (strcmp(subsys
, "platform") == 0) {
439 path_prepend(&path
, "platform-%s", udev_device_get_sysname(parent
));
440 parent
= skip_subsystem(parent
, "platform");
441 } else if (strcmp(subsys
, "acpi") == 0) {
442 path_prepend(&path
, "acpi-%s", udev_device_get_sysname(parent
));
443 parent
= skip_subsystem(parent
, "acpi");
444 } else if (strcmp(subsys
, "xen") == 0) {
445 path_prepend(&path
, "xen-%s", udev_device_get_sysname(parent
));
446 parent
= skip_subsystem(parent
, "xen");
447 } else if (strcmp(subsys
, "virtio") == 0) {
448 path_prepend(&path
, "virtio-pci-%s", udev_device_get_sysname(parent
));
449 parent
= skip_subsystem(parent
, "virtio");
452 parent
= udev_device_get_parent(parent
);
456 char tag
[UTIL_NAME_SIZE
];
460 /* compose valid udev tag name */
461 for (p
= path
, i
= 0; *p
; p
++) {
462 if ((*p
>= '0' && *p
<= '9') ||
463 (*p
>= 'A' && *p
<= 'Z') ||
464 (*p
>= 'a' && *p
<= 'z') ||
470 /* skip all leading '_' */
474 /* avoid second '_' */
480 /* strip trailing '_' */
481 while (i
> 0 && tag
[i
-1] == '_')
485 udev_builtin_add_property(dev
, test
, "ID_PATH", path
);
486 udev_builtin_add_property(dev
, test
, "ID_PATH_TAG", tag
);
493 const struct udev_builtin udev_builtin_path_id
= {
495 .cmd
= builtin_path_id
,
496 .help
= "compose persistent device path",