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-rw-r--r--src/udev/udev-builtin-path_id.c683
1 files changed, 683 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 0000000..7ce1c56
--- /dev/null
+++ b/src/udev/udev-builtin-path_id.c
@@ -0,0 +1,683 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * compose persistent device path
+ *
+ * Logic based on Hannes Reinecke's shell script.
+ */
+
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "alloc-util.h"
+#include "dirent-util.h"
+#include "fd-util.h"
+#include "libudev-util.h"
+#include "string-util.h"
+#include "strv.h"
+#include "sysexits.h"
+#include "udev-builtin.h"
+
+_printf_(2,3)
+static void path_prepend(char **path, const char *fmt, ...) {
+ va_list va;
+ _cleanup_free_ char *pre = NULL;
+ int r;
+
+ va_start(va, fmt);
+ r = vasprintf(&pre, fmt, va);
+ va_end(va);
+ if (r < 0) {
+ log_oom();
+ exit(EX_OSERR);
+ }
+
+ if (*path) {
+ char *new;
+
+ new = strjoin(pre, "-", *path);
+ if (!new) {
+ log_oom();
+ exit(EX_OSERR);
+ }
+
+ free_and_replace(*path, new);
+ } else
+ *path = TAKE_PTR(pre);
+}
+
+/*
+** Linux only supports 32 bit luns.
+** See drivers/scsi/scsi_scan.c::scsilun_to_int() for more details.
+*/
+static int format_lun_number(sd_device *dev, char **path) {
+ const char *sysnum;
+ unsigned long lun;
+ int r;
+
+ r = sd_device_get_sysnum(dev, &sysnum);
+ if (r < 0)
+ return r;
+ if (!sysnum)
+ return -ENOENT;
+
+ lun = strtoul(sysnum, NULL, 10);
+ if (lun < 256)
+ /* address method 0, peripheral device addressing with bus id of zero */
+ path_prepend(path, "lun-%lu", lun);
+ else
+ /* handle all other lun addressing methods by using a variant of the original lun format */
+ path_prepend(path, "lun-0x%04lx%04lx00000000", lun & 0xffff, (lun >> 16) & 0xffff);
+
+ return 0;
+}
+
+static sd_device *skip_subsystem(sd_device *dev, const char *subsys) {
+ sd_device *parent;
+
+ assert(dev);
+ assert(subsys);
+
+ for (parent = dev; ; ) {
+ const char *subsystem;
+
+ if (sd_device_get_subsystem(parent, &subsystem) < 0)
+ break;
+
+ if (!streq(subsystem, subsys))
+ break;
+
+ dev = parent;
+ if (sd_device_get_parent(dev, &parent) < 0)
+ break;
+ }
+
+ return dev;
+}
+
+static sd_device *handle_scsi_fibre_channel(sd_device *parent, char **path) {
+ sd_device *targetdev;
+ _cleanup_(sd_device_unrefp) sd_device *fcdev = NULL;
+ const char *port, *sysname;
+ _cleanup_free_ char *lun = NULL;
+
+ assert(parent);
+ assert(path);
+
+ if (sd_device_get_parent_with_subsystem_devtype(parent, "scsi", "scsi_target", &targetdev) < 0)
+ return NULL;
+ if (sd_device_get_sysname(targetdev, &sysname) < 0)
+ return NULL;
+ if (sd_device_new_from_subsystem_sysname(&fcdev, "fc_transport", sysname) < 0)
+ return NULL;
+ if (sd_device_get_sysattr_value(fcdev, "port_name", &port) < 0)
+ return NULL;
+
+ format_lun_number(parent, &lun);
+ path_prepend(path, "fc-%s-%s", port, lun);
+ return parent;
+}
+
+static sd_device *handle_scsi_sas_wide_port(sd_device *parent, char **path) {
+ sd_device *targetdev, *target_parent;
+ _cleanup_(sd_device_unrefp) sd_device *sasdev = NULL;
+ const char *sas_address, *sysname;
+ _cleanup_free_ char *lun = NULL;
+
+ assert(parent);
+ assert(path);
+
+ if (sd_device_get_parent_with_subsystem_devtype(parent, "scsi", "scsi_target", &targetdev) < 0)
+ return NULL;
+ if (sd_device_get_parent(targetdev, &target_parent) < 0)
+ return NULL;
+ if (sd_device_get_sysname(target_parent, &sysname) < 0)
+ return NULL;
+ if (sd_device_new_from_subsystem_sysname(&sasdev, "sas_device", sysname) < 0)
+ return NULL;
+ if (sd_device_get_sysattr_value(sasdev, "sas_address", &sas_address) < 0)
+ return NULL;
+
+ format_lun_number(parent, &lun);
+ path_prepend(path, "sas-%s-%s", sas_address, lun);
+ return parent;
+}
+
+static sd_device *handle_scsi_sas(sd_device *parent, char **path) {
+ sd_device *targetdev, *target_parent, *port, *expander;
+ _cleanup_(sd_device_unrefp) sd_device *target_sasdev = NULL, *expander_sasdev = NULL, *port_sasdev = NULL;
+ const char *sas_address = NULL;
+ const char *phy_id;
+ const char *phy_count, *sysname;
+ _cleanup_free_ char *lun = NULL;
+
+ assert(parent);
+ assert(path);
+
+ if (sd_device_get_parent_with_subsystem_devtype(parent, "scsi", "scsi_target", &targetdev) < 0)
+ return NULL;
+ if (sd_device_get_parent(targetdev, &target_parent) < 0)
+ return NULL;
+ if (sd_device_get_sysname(target_parent, &sysname) < 0)
+ return NULL;
+ /* Get sas device */
+ if (sd_device_new_from_subsystem_sysname(&target_sasdev, "sas_device", sysname) < 0)
+ return NULL;
+ /* The next parent is sas port */
+ if (sd_device_get_parent(target_parent, &port) < 0)
+ return NULL;
+ if (sd_device_get_sysname(port, &sysname) < 0)
+ return NULL;
+ /* Get port device */
+ if (sd_device_new_from_subsystem_sysname(&port_sasdev, "sas_port", sysname) < 0)
+ return NULL;
+ if (sd_device_get_sysattr_value(port_sasdev, "num_phys", &phy_count) < 0)
+ return NULL;
+
+ /* Check if we are simple disk */
+ if (strncmp(phy_count, "1", 2) != 0)
+ return handle_scsi_sas_wide_port(parent, path);
+
+ /* Get connected phy */
+ if (sd_device_get_sysattr_value(target_sasdev, "phy_identifier", &phy_id) < 0)
+ return NULL;
+
+ /* The port's parent is either hba or expander */
+ if (sd_device_get_parent(port, &expander) < 0)
+ return NULL;
+
+ if (sd_device_get_sysname(expander, &sysname) < 0)
+ return NULL;
+ /* Get expander device */
+ if (sd_device_new_from_subsystem_sysname(&expander_sasdev, "sas_device", sysname) >= 0) {
+ /* Get expander's address */
+ if (sd_device_get_sysattr_value(expander_sasdev, "sas_address", &sas_address) < 0)
+ return NULL;
+ }
+
+ format_lun_number(parent, &lun);
+ if (sas_address)
+ path_prepend(path, "sas-exp%s-phy%s-%s", sas_address, phy_id, lun);
+ else
+ path_prepend(path, "sas-phy%s-%s", phy_id, lun);
+
+ return parent;
+}
+
+static sd_device *handle_scsi_iscsi(sd_device *parent, char **path) {
+ sd_device *transportdev;
+ _cleanup_(sd_device_unrefp) sd_device *sessiondev = NULL, *conndev = NULL;
+ const char *target, *connname, *addr, *port;
+ _cleanup_free_ char *lun = NULL;
+ const char *sysname, *sysnum;
+
+ assert(parent);
+ assert(path);
+
+ /* find iscsi session */
+ for (transportdev = parent; ; ) {
+
+ if (sd_device_get_parent(transportdev, &transportdev) < 0)
+ return NULL;
+ if (sd_device_get_sysname(transportdev, &sysname) < 0)
+ return NULL;
+ if (startswith(sysname, "session"))
+ break;
+ }
+
+ /* find iscsi session device */
+ if (sd_device_new_from_subsystem_sysname(&sessiondev, "iscsi_session", sysname) < 0)
+ return NULL;
+
+ if (sd_device_get_sysattr_value(sessiondev, "targetname", &target) < 0)
+ return NULL;
+
+ if (sd_device_get_sysnum(transportdev, &sysnum) < 0 || !sysnum)
+ return NULL;
+ connname = strjoina("connection", sysnum, ":0");
+ if (sd_device_new_from_subsystem_sysname(&conndev, "iscsi_connection", connname) < 0)
+ return NULL;
+
+ if (sd_device_get_sysattr_value(conndev, "persistent_address", &addr) < 0)
+ return NULL;
+ if (sd_device_get_sysattr_value(conndev, "persistent_port", &port) < 0)
+ return NULL;
+
+ format_lun_number(parent, &lun);
+ path_prepend(path, "ip-%s:%s-iscsi-%s-%s", addr, port, target, lun);
+ return parent;
+}
+
+static sd_device *handle_scsi_ata(sd_device *parent, char **path) {
+ sd_device *targetdev, *target_parent;
+ _cleanup_(sd_device_unrefp) sd_device *atadev = NULL;
+ const char *port_no, *sysname;
+
+ assert(parent);
+ assert(path);
+
+ if (sd_device_get_parent_with_subsystem_devtype(parent, "scsi", "scsi_host", &targetdev) < 0)
+ return NULL;
+
+ if (sd_device_get_parent(targetdev, &target_parent) < 0)
+ return NULL;
+
+ if (sd_device_get_sysname(target_parent, &sysname) < 0)
+ return NULL;
+ if (sd_device_new_from_subsystem_sysname(&atadev, "ata_port", sysname) < 0)
+ return NULL;
+
+ if (sd_device_get_sysattr_value(atadev, "port_no", &port_no) < 0)
+ return NULL;
+
+ path_prepend(path, "ata-%s", port_no);
+ return parent;
+}
+
+static sd_device *handle_scsi_default(sd_device *parent, char **path) {
+ sd_device *hostdev;
+ int host, bus, target, lun;
+ const char *name, *base, *pos;
+ _cleanup_closedir_ DIR *dir = NULL;
+ struct dirent *dent;
+ int basenum = -1;
+
+ assert(parent);
+ assert(path);
+
+ if (sd_device_get_parent_with_subsystem_devtype(parent, "scsi", "scsi_host", &hostdev) < 0)
+ return NULL;
+
+ if (sd_device_get_sysname(parent, &name) < 0)
+ return NULL;
+ 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.
+ */
+
+ if (sd_device_get_syspath(hostdev, &base) < 0)
+ return NULL;
+ pos = strrchr(base, '/');
+ if (!pos)
+ return NULL;
+
+ base = strndupa(base, pos - base);
+ dir = opendir(base);
+ if (!dir)
+ return NULL;
+
+ FOREACH_DIRENT_ALL(dent, dir, break) {
+ char *rest;
+ int i;
+
+ if (dent->d_name[0] == '.')
+ continue;
+ if (!IN_SET(dent->d_type, DT_DIR, 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;
+ }
+ if (basenum == -1)
+ return hostdev;
+ host -= basenum;
+
+ path_prepend(path, "scsi-%u:%u:%u:%u", host, bus, target, lun);
+ return hostdev;
+}
+
+static sd_device *handle_scsi_hyperv(sd_device *parent, char **path, size_t guid_str_len) {
+ sd_device *hostdev;
+ sd_device *vmbusdev;
+ const char *guid_str;
+ _cleanup_free_ char *lun = NULL;
+ char guid[39];
+ size_t i, k;
+
+ assert(parent);
+ assert(path);
+ assert(guid_str_len < sizeof(guid));
+
+ if (sd_device_get_parent_with_subsystem_devtype(parent, "scsi", "scsi_host", &hostdev) < 0)
+ return NULL;
+
+ if (sd_device_get_parent(hostdev, &vmbusdev) < 0)
+ return NULL;
+
+ if (sd_device_get_sysattr_value(vmbusdev, "device_id", &guid_str) < 0)
+ return NULL;
+
+ if (strlen(guid_str) < guid_str_len || guid_str[0] != '{' || guid_str[guid_str_len-1] != '}')
+ return NULL;
+
+ for (i = 1, k = 0; i < guid_str_len-1; i++) {
+ if (guid_str[i] == '-')
+ continue;
+ guid[k++] = guid_str[i];
+ }
+ guid[k] = '\0';
+
+ format_lun_number(parent, &lun);
+ path_prepend(path, "vmbus-%s-%s", guid, lun);
+ return parent;
+}
+
+static sd_device *handle_scsi(sd_device *parent, char **path, bool *supported_parent) {
+ const char *devtype, *id, *name;
+
+ if (sd_device_get_devtype(parent, &devtype) < 0 ||
+ !streq(devtype, "scsi_device"))
+ return parent;
+
+ /* firewire */
+ if (sd_device_get_sysattr_value(parent, "ieee1394_id", &id) >= 0) {
+ path_prepend(path, "ieee1394-0x%s", id);
+ *supported_parent = true;
+ return skip_subsystem(parent, "scsi");
+ }
+
+ /* scsi sysfs does not have a "subsystem" for the transport */
+ if (sd_device_get_syspath(parent, &name) < 0)
+ return NULL;
+
+ if (strstr(name, "/rport-")) {
+ *supported_parent = true;
+ return handle_scsi_fibre_channel(parent, path);
+ }
+
+ if (strstr(name, "/end_device-")) {
+ *supported_parent = true;
+ return handle_scsi_sas(parent, path);
+ }
+
+ if (strstr(name, "/session")) {
+ *supported_parent = true;
+ return handle_scsi_iscsi(parent, path);
+ }
+
+ if (strstr(name, "/ata"))
+ return handle_scsi_ata(parent, path);
+
+ if (strstr(name, "/vmbus_"))
+ return handle_scsi_hyperv(parent, path, 37);
+ else if (strstr(name, "/VMBUS"))
+ return handle_scsi_hyperv(parent, path, 38);
+
+ return handle_scsi_default(parent, path);
+}
+
+static sd_device *handle_cciss(sd_device *parent, char **path) {
+ const char *str;
+ unsigned controller, disk;
+
+ if (sd_device_get_sysname(parent, &str) < 0)
+ return NULL;
+ if (sscanf(str, "c%ud%u%*s", &controller, &disk) != 2)
+ return NULL;
+
+ path_prepend(path, "cciss-disk%u", disk);
+ return skip_subsystem(parent, "cciss");
+}
+
+static void handle_scsi_tape(sd_device *dev, char **path) {
+ const char *name;
+
+ /* must be the last device in the syspath */
+ if (*path)
+ return;
+
+ if (sd_device_get_sysname(dev, &name) < 0)
+ return;
+
+ if (startswith(name, "nst") && strchr("lma", name[3]))
+ path_prepend(path, "nst%c", name[3]);
+ else if (startswith(name, "st") && strchr("lma", name[2]))
+ path_prepend(path, "st%c", name[2]);
+}
+
+static sd_device *handle_usb(sd_device *parent, char **path) {
+ const char *devtype, *str, *port;
+
+ if (sd_device_get_devtype(parent, &devtype) < 0)
+ return parent;
+ if (!STR_IN_SET(devtype, "usb_interface", "usb_device"))
+ return parent;
+
+ if (sd_device_get_sysname(parent, &str) < 0)
+ return parent;
+ port = strchr(str, '-');
+ if (!port)
+ return parent;
+ port++;
+
+ path_prepend(path, "usb-0:%s", port);
+ return skip_subsystem(parent, "usb");
+}
+
+static sd_device *handle_bcma(sd_device *parent, char **path) {
+ const char *sysname;
+ unsigned core;
+
+ if (sd_device_get_sysname(parent, &sysname) < 0)
+ return NULL;
+ if (sscanf(sysname, "bcma%*u:%u", &core) != 1)
+ return NULL;
+
+ path_prepend(path, "bcma-%u", core);
+ return parent;
+}
+
+/* Handle devices of AP bus in System z platform. */
+static sd_device *handle_ap(sd_device *parent, char **path) {
+ const char *type, *func;
+
+ assert(parent);
+ assert(path);
+
+ if (sd_device_get_sysattr_value(parent, "type", &type) >= 0 &&
+ sd_device_get_sysattr_value(parent, "ap_functions", &func) >= 0)
+ path_prepend(path, "ap-%s-%s", type, func);
+ else {
+ const char *sysname;
+
+ if (sd_device_get_sysname(parent, &sysname) >= 0)
+ path_prepend(path, "ap-%s", sysname);
+ }
+
+ return skip_subsystem(parent, "ap");
+}
+
+static int builtin_path_id(sd_device *dev, int argc, char *argv[], bool test) {
+ sd_device *parent;
+ _cleanup_free_ char *path = NULL;
+ bool supported_transport = false;
+ bool supported_parent = false;
+ const char *subsystem;
+
+ assert(dev);
+
+ /* walk up the chain of devices and compose path */
+ parent = dev;
+ while (parent) {
+ const char *subsys, *sysname;
+
+ if (sd_device_get_subsystem(parent, &subsys) < 0 ||
+ sd_device_get_sysname(parent, &sysname) < 0) {
+ ;
+ } else if (streq(subsys, "scsi_tape")) {
+ handle_scsi_tape(parent, &path);
+ } else if (streq(subsys, "scsi")) {
+ parent = handle_scsi(parent, &path, &supported_parent);
+ supported_transport = true;
+ } else if (streq(subsys, "cciss")) {
+ parent = handle_cciss(parent, &path);
+ supported_transport = true;
+ } else if (streq(subsys, "usb")) {
+ parent = handle_usb(parent, &path);
+ supported_transport = true;
+ } else if (streq(subsys, "bcma")) {
+ parent = handle_bcma(parent, &path);
+ supported_transport = true;
+ } else if (streq(subsys, "serio")) {
+ const char *sysnum;
+
+ if (sd_device_get_sysnum(parent, &sysnum) >= 0 && sysnum) {
+ path_prepend(&path, "serio-%s", sysnum);
+ parent = skip_subsystem(parent, "serio");
+ }
+ } else if (streq(subsys, "pci")) {
+ path_prepend(&path, "pci-%s", sysname);
+ parent = skip_subsystem(parent, "pci");
+ supported_parent = true;
+ } else if (streq(subsys, "platform")) {
+ path_prepend(&path, "platform-%s", sysname);
+ parent = skip_subsystem(parent, "platform");
+ supported_transport = true;
+ supported_parent = true;
+ } else if (streq(subsys, "acpi")) {
+ path_prepend(&path, "acpi-%s", sysname);
+ parent = skip_subsystem(parent, "acpi");
+ supported_parent = true;
+ } else if (streq(subsys, "xen")) {
+ path_prepend(&path, "xen-%s", sysname);
+ parent = skip_subsystem(parent, "xen");
+ supported_parent = true;
+ } else if (streq(subsys, "virtio")) {
+ parent = skip_subsystem(parent, "virtio");
+ supported_transport = true;
+ } else if (streq(subsys, "scm")) {
+ path_prepend(&path, "scm-%s", sysname);
+ parent = skip_subsystem(parent, "scm");
+ supported_transport = true;
+ supported_parent = true;
+ } else if (streq(subsys, "ccw")) {
+ path_prepend(&path, "ccw-%s", sysname);
+ parent = skip_subsystem(parent, "ccw");
+ supported_transport = true;
+ supported_parent = true;
+ } else if (streq(subsys, "ccwgroup")) {
+ path_prepend(&path, "ccwgroup-%s", sysname);
+ parent = skip_subsystem(parent, "ccwgroup");
+ supported_transport = true;
+ supported_parent = true;
+ } else if (streq(subsys, "ap")) {
+ parent = handle_ap(parent, &path);
+ supported_transport = true;
+ supported_parent = true;
+ } else if (streq(subsys, "iucv")) {
+ path_prepend(&path, "iucv-%s", sysname);
+ parent = skip_subsystem(parent, "iucv");
+ supported_transport = true;
+ supported_parent = true;
+ } else if (streq(subsys, "nvme")) {
+ const char *nsid;
+
+ if (sd_device_get_sysattr_value(dev, "nsid", &nsid) >= 0) {
+ path_prepend(&path, "nvme-%s", nsid);
+ parent = skip_subsystem(parent, "nvme");
+ supported_parent = true;
+ supported_transport = true;
+ }
+ }
+
+ if (!parent)
+ break;
+ if (sd_device_get_parent(parent, &parent) < 0)
+ break;
+ }
+
+ if (!path)
+ return -ENOENT;
+
+ /*
+ * Do not return devices with an unknown parent device type. They
+ * might produce conflicting IDs if the parent does not provide a
+ * unique and predictable name.
+ */
+ if (!supported_parent)
+ return -ENOENT;
+
+ /*
+ * Do not return block devices without a well-known transport. Some
+ * devices do not expose their buses and do not provide a unique
+ * and predictable name that way.
+ */
+ if (sd_device_get_subsystem(dev, &subsystem) >= 0 &&
+ streq(subsystem, "block") &&
+ !supported_transport)
+ return -ENOENT;
+
+ {
+ 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);
+ }
+
+ return 0;
+}
+
+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 (git 2.39.1) at 2024-11-16 19:08:49 +0000