diff options
Diffstat (limited to 'src/udev/udev-builtin-path_id.c')
| -rw-r--r-- | src/udev/udev-builtin-path_id.c | 498 |
1 files changed, 498 insertions, 0 deletions
diff --git a/src/udev/udev-builtin-path_id.c b/src/udev/udev-builtin-path_id.c new file mode 100644 index 0000000000..a8559d2dd4 --- /dev/null +++ b/src/udev/udev-builtin-path_id.c @@ -0,0 +1,498 @@ +/* + * compose persistent device path + * + * Copyright (C) 2009-2011 Kay Sievers <kay.sievers@vrfy.org> + * + * Logic based on Hannes Reinecke's shell script. + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <stdio.h> +#include <stdlib.h> +#include <stdarg.h> +#include <unistd.h> +#include <string.h> +#include <ctype.h> +#include <fcntl.h> +#include <errno.h> +#include <dirent.h> +#include <getopt.h> + +#include "udev.h" + +static int path_prepend(char **path, const char *fmt, ...) +{ + va_list va; + char *pre; + int err = 0; + + va_start(va, fmt); + err = vasprintf(&pre, fmt, va); + va_end(va); + if (err < 0) + goto out; + + if (*path != NULL) { + char *new; + + err = asprintf(&new, "%s-%s", pre, *path); + free(pre); + if (err < 0) + goto out; + free(*path); + *path = new; + } else { + *path = pre; + } +out: + return err; +} + +/* +** Linux only supports 32 bit luns. +** See drivers/scsi/scsi_scan.c::scsilun_to_int() for more details. +*/ +static int format_lun_number(struct udev_device *dev, char **path) +{ + unsigned long lun = strtoul(udev_device_get_sysnum(dev), NULL, 10); + + /* address method 0, peripheral device addressing with bus id of zero */ + if (lun < 256) + return path_prepend(path, "lun-%d", lun); + /* handle all other lun addressing methods by using a variant of the original lun format */ + return path_prepend(path, "lun-0x%04x%04x00000000", (lun & 0xffff), (lun >> 16) & 0xffff); +} + +static struct udev_device *skip_subsystem(struct udev_device *dev, const char *subsys) +{ + struct udev_device *parent = dev; + + while (parent != NULL) { + const char *subsystem; + + subsystem = udev_device_get_subsystem(parent); + if (subsystem == NULL || strcmp(subsystem, subsys) != 0) + break; + dev = parent; + parent = udev_device_get_parent(parent); + } + return dev; +} + +static struct udev_device *handle_scsi_fibre_channel(struct udev_device *parent, char **path) +{ + struct udev *udev = udev_device_get_udev(parent); + struct udev_device *targetdev; + struct udev_device *fcdev = NULL; + const char *port; + char *lun = NULL;; + + targetdev = udev_device_get_parent_with_subsystem_devtype(parent, "scsi", "scsi_target"); + if (targetdev == NULL) + return NULL; + + fcdev = udev_device_new_from_subsystem_sysname(udev, "fc_transport", udev_device_get_sysname(targetdev)); + if (fcdev == NULL) + return NULL; + port = udev_device_get_sysattr_value(fcdev, "port_name"); + if (port == NULL) { + parent = NULL; + goto out; + } + + format_lun_number(parent, &lun); + path_prepend(path, "fc-%s-%s", port, lun); + if (lun) + free(lun); +out: + udev_device_unref(fcdev); + return parent; +} + +static struct udev_device *handle_scsi_sas(struct udev_device *parent, char **path) +{ + struct udev *udev = udev_device_get_udev(parent); + struct udev_device *targetdev; + struct udev_device *target_parent; + struct udev_device *sasdev; + const char *sas_address; + char *lun = NULL; + + targetdev = udev_device_get_parent_with_subsystem_devtype(parent, "scsi", "scsi_target"); + if (targetdev == NULL) + return NULL; + + target_parent = udev_device_get_parent(targetdev); + if (target_parent == NULL) + return NULL; + + sasdev = udev_device_new_from_subsystem_sysname(udev, "sas_device", + udev_device_get_sysname(target_parent)); + if (sasdev == NULL) + return NULL; + + sas_address = udev_device_get_sysattr_value(sasdev, "sas_address"); + if (sas_address == NULL) { + parent = NULL; + goto out; + } + + format_lun_number(parent, &lun); + path_prepend(path, "sas-%s-%s", sas_address, lun); + if (lun) + free(lun); +out: + udev_device_unref(sasdev); + return parent; +} + +static struct udev_device *handle_scsi_iscsi(struct udev_device *parent, char **path) +{ + struct udev *udev = udev_device_get_udev(parent); + struct udev_device *transportdev; + struct udev_device *sessiondev = NULL; + const char *target; + char *connname; + struct udev_device *conndev = NULL; + const char *addr; + const char *port; + char *lun = NULL; + + /* find iscsi session */ + transportdev = parent; + for (;;) { + transportdev = udev_device_get_parent(transportdev); + if (transportdev == NULL) + return NULL; + if (strncmp(udev_device_get_sysname(transportdev), "session", 7) == 0) + break; + } + + /* find iscsi session device */ + sessiondev = udev_device_new_from_subsystem_sysname(udev, "iscsi_session", udev_device_get_sysname(transportdev)); + if (sessiondev == NULL) + return NULL; + target = udev_device_get_sysattr_value(sessiondev, "targetname"); + if (target == NULL) { + parent = NULL; + goto out; + } + + if (asprintf(&connname, "connection%s:0", udev_device_get_sysnum(transportdev)) < 0) { + parent = NULL; + goto out; + } + conndev = udev_device_new_from_subsystem_sysname(udev, "iscsi_connection", connname); + free(connname); + if (conndev == NULL) { + parent = NULL; + goto out; + } + addr = udev_device_get_sysattr_value(conndev, "persistent_address"); + port = udev_device_get_sysattr_value(conndev, "persistent_port"); + if (addr == NULL || port == NULL) { + parent = NULL; + goto out; + } + + format_lun_number(parent, &lun); + path_prepend(path, "ip-%s:%s-iscsi-%s-%s", addr, port, target, lun); + if (lun) + free(lun); +out: + udev_device_unref(sessiondev); + udev_device_unref(conndev); + return parent; +} + +static struct udev_device *handle_scsi_default(struct udev_device *parent, char **path) +{ + struct udev_device *hostdev; + int host, bus, target, lun; + const char *name; + char *base; + char *pos; + DIR *dir; + struct dirent *dent; + int basenum; + + hostdev = udev_device_get_parent_with_subsystem_devtype(parent, "scsi", "scsi_host"); + if (hostdev == NULL) + return NULL; + + name = udev_device_get_sysname(parent); + if (sscanf(name, "%d:%d:%d:%d", &host, &bus, &target, &lun) != 4) + return NULL; + + /* rebase host offset to get the local relative number */ + basenum = -1; + base = strdup(udev_device_get_syspath(hostdev)); + if (base == NULL) + return NULL; + pos = strrchr(base, '/'); + if (pos == NULL) { + parent = NULL; + goto out; + } + pos[0] = '\0'; + dir = opendir(base); + if (dir == NULL) { + parent = NULL; + goto out; + } + for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) { + char *rest; + int i; + + if (dent->d_name[0] == '.') + continue; + if (dent->d_type != DT_DIR && dent->d_type != DT_LNK) + continue; + if (strncmp(dent->d_name, "host", 4) != 0) + continue; + i = strtoul(&dent->d_name[4], &rest, 10); + if (rest[0] != '\0') + continue; + /* + * find the smallest number; the host really needs to export its + * own instance number per parent device; relying on the global host + * enumeration and plainly rebasing the numbers sounds unreliable + */ + if (basenum == -1 || i < basenum) + basenum = i; + } + closedir(dir); + if (basenum == -1) { + parent = NULL; + goto out; + } + host -= basenum; + + path_prepend(path, "scsi-%u:%u:%u:%u", host, bus, target, lun); +out: + free(base); + return hostdev; +} + +static struct udev_device *handle_scsi(struct udev_device *parent, char **path) +{ + const char *devtype; + const char *name; + const char *id; + + devtype = udev_device_get_devtype(parent); + if (devtype == NULL || strcmp(devtype, "scsi_device") != 0) + return parent; + + /* firewire */ + id = udev_device_get_sysattr_value(parent, "ieee1394_id"); + if (id != NULL) { + parent = skip_subsystem(parent, "scsi"); + path_prepend(path, "ieee1394-0x%s", id); + goto out; + } + + /* lousy scsi sysfs does not have a "subsystem" for the transport */ + name = udev_device_get_syspath(parent); + + if (strstr(name, "/rport-") != NULL) { + parent = handle_scsi_fibre_channel(parent, path); + goto out; + } + + if (strstr(name, "/end_device-") != NULL) { + parent = handle_scsi_sas(parent, path); + goto out; + } + + if (strstr(name, "/session") != NULL) { + parent = handle_scsi_iscsi(parent, path); + goto out; + } + + /* + * We do not support the ATA transport class, it creates duplicated link + * names as the fake SCSI host adapters are all separated, they are all + * re-based as host == 0. ATA should just stop faking two duplicated + * hierarchies for a single topology and leave the SCSI stuff alone; + * until that happens, there are no by-path/ links for ATA devices behind + * an ATA transport class. + */ + if (strstr(name, "/ata") != NULL) { + parent = NULL; + goto out; + } + + parent = handle_scsi_default(parent, path); +out: + return parent; +} + +static void handle_scsi_tape(struct udev_device *dev, char **path) +{ + const char *name; + + /* must be the last device in the syspath */ + if (*path != NULL) + return; + + name = udev_device_get_sysname(dev); + if (strncmp(name, "nst", 3) == 0 && strchr("lma", name[3]) != NULL) + path_prepend(path, "nst%c", name[3]); + else if (strncmp(name, "st", 2) == 0 && strchr("lma", name[2]) != NULL) + path_prepend(path, "st%c", name[2]); +} + +static struct udev_device *handle_usb(struct udev_device *parent, char **path) +{ + const char *devtype; + const char *str; + const char *port; + + devtype = udev_device_get_devtype(parent); + if (devtype == NULL) + return parent; + if (strcmp(devtype, "usb_interface") != 0 && strcmp(devtype, "usb_device") != 0) + return parent; + + str = udev_device_get_sysname(parent); + port = strchr(str, '-'); + if (port == NULL) + return parent; + port++; + + parent = skip_subsystem(parent, "usb"); + path_prepend(path, "usb-0:%s", port); + return parent; +} + +static struct udev_device *handle_ccw(struct udev_device *parent, struct udev_device *dev, char **path) +{ + struct udev_device *scsi_dev; + + scsi_dev = udev_device_get_parent_with_subsystem_devtype(dev, "scsi", "scsi_device"); + if (scsi_dev != NULL) { + const char *wwpn; + const char *lun; + const char *hba_id; + + hba_id = udev_device_get_sysattr_value(scsi_dev, "hba_id"); + wwpn = udev_device_get_sysattr_value(scsi_dev, "wwpn"); + lun = udev_device_get_sysattr_value(scsi_dev, "fcp_lun"); + if (hba_id != NULL && lun != NULL && wwpn != NULL) { + path_prepend(path, "ccw-%s-zfcp-%s:%s", hba_id, wwpn, lun); + goto out; + } + } + + path_prepend(path, "ccw-%s", udev_device_get_sysname(parent)); +out: + parent = skip_subsystem(parent, "ccw"); + return parent; +} + +static int builtin_path_id(struct udev_device *dev, int argc, char *argv[], bool test) +{ + struct udev_device *parent; + char *path = NULL; + + /* S390 ccw bus */ + parent = udev_device_get_parent_with_subsystem_devtype(dev, "ccw", NULL); + if (parent != NULL) { + handle_ccw(parent, dev, &path); + goto out; + } + + /* walk up the chain of devices and compose path */ + parent = dev; + while (parent != NULL) { + const char *subsys; + + subsys = udev_device_get_subsystem(parent); + if (subsys == NULL) { + ; + } else if (strcmp(subsys, "scsi_tape") == 0) { + handle_scsi_tape(parent, &path); + } else if (strcmp(subsys, "scsi") == 0) { + parent = handle_scsi(parent, &path); + } else if (strcmp(subsys, "usb") == 0) { + parent = handle_usb(parent, &path); + } else if (strcmp(subsys, "serio") == 0) { + path_prepend(&path, "serio-%s", udev_device_get_sysnum(parent)); + parent = skip_subsystem(parent, "serio"); + } else if (strcmp(subsys, "pci") == 0) { + path_prepend(&path, "pci-%s", udev_device_get_sysname(parent)); + parent = skip_subsystem(parent, "pci"); + } else if (strcmp(subsys, "platform") == 0) { + path_prepend(&path, "platform-%s", udev_device_get_sysname(parent)); + parent = skip_subsystem(parent, "platform"); + } else if (strcmp(subsys, "acpi") == 0) { + path_prepend(&path, "acpi-%s", udev_device_get_sysname(parent)); + parent = skip_subsystem(parent, "acpi"); + } else if (strcmp(subsys, "xen") == 0) { + path_prepend(&path, "xen-%s", udev_device_get_sysname(parent)); + parent = skip_subsystem(parent, "xen"); + } else if (strcmp(subsys, "virtio") == 0) { + path_prepend(&path, "virtio-pci-%s", udev_device_get_sysname(parent)); + parent = skip_subsystem(parent, "virtio"); + } + + parent = udev_device_get_parent(parent); + } +out: + if (path != NULL) { + char tag[UTIL_NAME_SIZE]; + size_t i; + const char *p; + + /* compose valid udev tag name */ + for (p = path, i = 0; *p; p++) { + if ((*p >= '0' && *p <= '9') || + (*p >= 'A' && *p <= 'Z') || + (*p >= 'a' && *p <= 'z') || + *p == '-') { + tag[i++] = *p; + continue; + } + + /* skip all leading '_' */ + if (i == 0) + continue; + + /* avoid second '_' */ + if (tag[i-1] == '_') + continue; + + tag[i++] = '_'; + } + /* strip trailing '_' */ + while (i > 0 && tag[i-1] == '_') + i--; + tag[i] = '\0'; + + udev_builtin_add_property(dev, test, "ID_PATH", path); + udev_builtin_add_property(dev, test, "ID_PATH_TAG", tag); + free(path); + return EXIT_SUCCESS; + } + return EXIT_FAILURE; +} + +const struct udev_builtin udev_builtin_path_id = { + .name = "path_id", + .cmd = builtin_path_id, + .help = "compose persistent device path", + .run_once = true, +}; |