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Diffstat (limited to 'src/udev/udev-builtin-path_id.c')
-rw-r--r--src/udev/udev-builtin-path_id.c549
1 files changed, 549 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..bfdedc0989
--- /dev/null
+++ b/src/udev/udev-builtin-path_id.c
@@ -0,0 +1,549 @@
+/*
+ * compose persistent device path
+ *
+ * Copyright (C) 2009-2011 Kay Sievers <kay@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 (startswith(udev_device_get_sysname(transportdev), "session"))
+ 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
+ *
+ * Note: This is by definition racy, unreliable and too simple.
+ * Please do not copy this model anywhere. It's just a left-over
+ * from the time we had no idea how things should look like in
+ * the end.
+ *
+ * Making assumptions about a global in-kernel counter and use
+ * that to calculate a local offset is a very broken concept. It
+ * can only work as long as things are in strict order.
+ *
+ * The kernel needs to export the instance/port number of a
+ * controller directly, without the need for rebase magic like
+ * this. Manual driver unbind/bind, parallel hotplug/unplug will
+ * get into the way of this "I hope it works" logic.
+ */
+ 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 (!startswith(dent->d_name, "host"))
+ 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 struct udev_device *handle_cciss(struct udev_device *parent, char **path)
+{
+ const char *str;
+ unsigned int controller, disk;
+
+ str = udev_device_get_sysname(parent);
+ if (sscanf(str, "c%ud%u%*s", &controller, &disk) != 2)
+ return NULL;
+
+ path_prepend(path, "cciss-disk%u", disk);
+ parent = skip_subsystem(parent, "cciss");
+ 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 (startswith(name, "nst") && strchr("lma", name[3]) != NULL)
+ path_prepend(path, "nst%c", name[3]);
+ else if (startswith(name, "st") && 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;
+ bool some_transport = false;
+
+ /* 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);
+ some_transport = true;
+ } else if (strcmp(subsys, "cciss") == 0) {
+ parent = handle_cciss(parent, &path);
+ some_transport = true;
+ } else if (strcmp(subsys, "usb") == 0) {
+ parent = handle_usb(parent, &path);
+ some_transport = true;
+ } 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");
+ some_transport = true;
+ } 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");
+ } else if (strcmp(subsys, "scm") == 0) {
+ path_prepend(&path, "scm-%s", udev_device_get_sysname(parent));
+ parent = skip_subsystem(parent, "scm");
+ }
+
+ parent = udev_device_get_parent(parent);
+ }
+
+ /*
+ * Do not return a single-parent-device-only for block
+ * devices, they might have entire buses behind it which
+ * do not get unique IDs only by using the parent device.
+ */
+ if (!some_transport && streq(udev_device_get_subsystem(dev), "block")) {
+ free(path);
+ path = NULL;
+ }
+
+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,
+};
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-01 02:16:47 +0000