/*
* compose persistent device path
*
- * Copyright (C) 2009-2011 Kay Sievers <kay.sievers@vrfy.org>
+ * Copyright (C) 2009-2011 Kay Sievers <kay@vrfy.org>
*
* Logic based on Hannes Reinecke's shell script.
*
#include "udev.h"
-static int path_prepend(char **path, const char *fmt, ...)
-{
+_printf_(2,3)
+static int path_prepend(char **path, const char *fmt, ...) {
va_list va;
char *pre;
int err = 0;
** 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)
-{
+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);
+ return path_prepend(path, "lun-%lu", 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);
+ return path_prepend(path, "lun-0x%04lx%04lx00000000", lun & 0xffff, (lun >> 16) & 0xffff);
}
-static struct udev_device *skip_subsystem(struct udev_device *dev, const char *subsys)
-{
+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)
+ if (subsystem == NULL || !streq(subsystem, subsys))
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)
-{
+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;;
+ char *lun = NULL;
targetdev = udev_device_get_parent_with_subsystem_devtype(parent, "scsi", "scsi_target");
if (targetdev == NULL)
return parent;
}
-static struct udev_device *handle_scsi_sas(struct udev_device *parent, char **path)
-{
+static struct udev_device *handle_scsi_sas_wide_port(struct udev_device *parent, char **path) {
struct udev *udev = udev_device_get_udev(parent);
struct udev_device *targetdev;
struct udev_device *target_parent;
return parent;
}
-static struct udev_device *handle_scsi_iscsi(struct udev_device *parent, char **path)
+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 *port;
+ struct udev_device *expander;
+ struct udev_device *target_sasdev = NULL;
+ struct udev_device *expander_sasdev = NULL;
+ struct udev_device *port_sasdev = NULL;
+ const char *sas_address = NULL;
+ const char *phy_id;
+ const char *phy_count;
+ 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;
+
+ /* Get sas device */
+ target_sasdev = udev_device_new_from_subsystem_sysname(udev,
+ "sas_device", udev_device_get_sysname(target_parent));
+ if (target_sasdev == NULL)
+ return NULL;
+
+ /* The next parent is sas port */
+ port = udev_device_get_parent(target_parent);
+ if (port == NULL) {
+ parent = NULL;
+ goto out;
+ }
+
+ /* Get port device */
+ port_sasdev = udev_device_new_from_subsystem_sysname(udev,
+ "sas_port", udev_device_get_sysname(port));
+
+ phy_count = udev_device_get_sysattr_value(port_sasdev, "num_phys");
+ if (phy_count == NULL) {
+ parent = NULL;
+ goto out;
+ }
+
+ /* Check if we are simple disk */
+ if (strncmp(phy_count, "1", 2) != 0) {
+ parent = handle_scsi_sas_wide_port(parent, path);
+ goto out;
+ }
+
+ /* Get connected phy */
+ phy_id = udev_device_get_sysattr_value(target_sasdev, "phy_identifier");
+ if (phy_id == NULL) {
+ parent = NULL;
+ goto out;
+ }
+
+ /* The port's parent is either hba or expander */
+ expander = udev_device_get_parent(port);
+ if (expander == NULL) {
+ parent = NULL;
+ goto out;
+ }
+
+ /* Get expander device */
+ expander_sasdev = udev_device_new_from_subsystem_sysname(udev,
+ "sas_device", udev_device_get_sysname(expander));
+ if (expander_sasdev != NULL) {
+ /* Get expander's address */
+ sas_address = udev_device_get_sysattr_value(expander_sasdev,
+ "sas_address");
+ if (sas_address == NULL) {
+ parent = NULL;
+ goto out;
+ }
+ }
+
+ 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);
+
+ if (lun)
+ free(lun);
+out:
+ udev_device_unref(target_sasdev);
+ udev_device_unref(expander_sasdev);
+ udev_device_unref(port_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;
return parent;
}
-static struct udev_device *handle_scsi_default(struct udev_device *parent, char **path)
-{
+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;
if (sscanf(name, "%d:%d:%d:%d", &host, &bus, &target, &lun) != 4)
return NULL;
- /* rebase host offset to get the local relative number */
+ /*
+ * 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 hostdev;
}
-static struct udev_device *handle_scsi(struct udev_device *parent, char **path)
-{
+static struct udev_device *handle_scsi_hyperv(struct udev_device *parent, char **path) {
+ struct udev_device *hostdev;
+ struct udev_device *vmbusdev;
+ const char *guid_str;
+ char *lun = NULL;
+ char guid[38];
+ size_t i, k;
+
+ hostdev = udev_device_get_parent_with_subsystem_devtype(parent, "scsi", "scsi_host");
+ if (!hostdev)
+ return NULL;
+
+ vmbusdev = udev_device_get_parent(hostdev);
+ if (!vmbusdev)
+ return NULL;
+
+ guid_str = udev_device_get_sysattr_value(vmbusdev, "device_id");
+ if (!guid_str)
+ return NULL;
+
+ if (strlen(guid_str) < 37 || guid_str[0] != '{' || guid_str[36] != '}')
+ return NULL;
+
+ for (i = 1, k = 0; i < 36; 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);
+ free(lun);
+ return parent;
+}
+
+static struct udev_device *handle_scsi(struct udev_device *parent, char **path, bool *supported_parent) {
const char *devtype;
const char *name;
const char *id;
devtype = udev_device_get_devtype(parent);
- if (devtype == NULL || strcmp(devtype, "scsi_device") != 0)
+ if (devtype == NULL || !streq(devtype, "scsi_device"))
return parent;
/* firewire */
if (id != NULL) {
parent = skip_subsystem(parent, "scsi");
path_prepend(path, "ieee1394-0x%s", id);
+ *supported_parent = true;
goto out;
}
- /* lousy scsi sysfs does not have a "subsystem" for the transport */
+ /* 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);
+ *supported_parent = true;
goto out;
}
if (strstr(name, "/end_device-") != NULL) {
parent = handle_scsi_sas(parent, path);
+ *supported_parent = true;
goto out;
}
if (strstr(name, "/session") != NULL) {
parent = handle_scsi_iscsi(parent, path);
+ *supported_parent = true;
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.
+ * We do not support the ATA transport class, it uses global counters
+ * to name the ata devices which numbers spread across multiple
+ * controllers.
+ *
+ * The real link numbers are not exported. Also, possible chains of ports
+ * behind port multipliers cannot be composed that way.
+ *
+ * Until all that is solved at the kernel level, there are no by-path/
+ * links for ATA devices.
*/
if (strstr(name, "/ata") != NULL) {
parent = NULL;
goto out;
}
+ if (strstr(name, "/vmbus_") != NULL) {
+ parent = handle_scsi_hyperv(parent, path);
+ goto out;
+ }
+
parent = handle_scsi_default(parent, path);
out:
return parent;
}
-static struct udev_device *handle_cciss(struct udev_device *parent, char **path)
-{
+static struct udev_device *handle_cciss(struct udev_device *parent, char **path) {
const char *str;
unsigned int controller, disk;
return parent;
}
-static void handle_scsi_tape(struct udev_device *dev, char **path)
-{
+static void handle_scsi_tape(struct udev_device *dev, char **path) {
const char *name;
/* must be the last device in the syspath */
path_prepend(path, "st%c", name[2]);
}
-static struct udev_device *handle_usb(struct udev_device *parent, char **path)
-{
+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)
+ if (!streq(devtype, "usb_interface") && !streq(devtype, "usb_device"))
return parent;
str = udev_device_get_sysname(parent);
return parent;
}
-static struct udev_device *handle_ccw(struct udev_device *parent, struct udev_device *dev, char **path)
-{
+static struct udev_device *handle_bcma(struct udev_device *parent, char **path) {
+ const char *sysname;
+ unsigned int core;
+
+ sysname = udev_device_get_sysname(parent);
+ if (sscanf(sysname, "bcma%*u:%u", &core) != 1)
+ return NULL;
+
+ path_prepend(path, "bcma-%u", core);
+ 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");
return parent;
}
-static int builtin_path_id(struct udev_device *dev, int argc, char *argv[], bool test)
-{
+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;
+ bool supported_transport = false;
+ bool supported_parent = false;
/* S390 ccw bus */
parent = udev_device_get_parent_with_subsystem_devtype(dev, "ccw", NULL);
subsys = udev_device_get_subsystem(parent);
if (subsys == NULL) {
;
- } else if (strcmp(subsys, "scsi_tape") == 0) {
+ } else if (streq(subsys, "scsi_tape")) {
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) {
+ } 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);
- some_transport = true;
- } else if (strcmp(subsys, "usb") == 0) {
+ supported_transport = true;
+ } else if (streq(subsys, "usb")) {
parent = handle_usb(parent, &path);
- some_transport = true;
- } else if (strcmp(subsys, "serio") == 0) {
+ supported_transport = true;
+ } else if (streq(subsys, "bcma")) {
+ parent = handle_bcma(parent, &path);
+ supported_transport = true;
+ } else if (streq(subsys, "serio")) {
path_prepend(&path, "serio-%s", udev_device_get_sysnum(parent));
parent = skip_subsystem(parent, "serio");
- } else if (strcmp(subsys, "pci") == 0) {
+ } else if (streq(subsys, "pci")) {
path_prepend(&path, "pci-%s", udev_device_get_sysname(parent));
parent = skip_subsystem(parent, "pci");
- } else if (strcmp(subsys, "platform") == 0) {
+ supported_parent = true;
+ } else if (streq(subsys, "platform")) {
path_prepend(&path, "platform-%s", udev_device_get_sysname(parent));
parent = skip_subsystem(parent, "platform");
- some_transport = true;
- } else if (strcmp(subsys, "acpi") == 0) {
+ supported_transport = true;
+ supported_parent = true;
+ } else if (streq(subsys, "acpi")) {
path_prepend(&path, "acpi-%s", udev_device_get_sysname(parent));
parent = skip_subsystem(parent, "acpi");
- } else if (strcmp(subsys, "xen") == 0) {
+ supported_parent = true;
+ } else if (streq(subsys, "xen")) {
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");
+ supported_parent = true;
+ } else if (streq(subsys, "scm")) {
+ path_prepend(&path, "scm-%s", udev_device_get_sysname(parent));
+ parent = skip_subsystem(parent, "scm");
+ supported_transport = true;
+ supported_parent = true;
}
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.
+ * 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) {
+ free(path);
+ path = NULL;
+ }
+
+ /*
+ * 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 (!some_transport && streq(udev_device_get_subsystem(dev), "block")) {
+ if (streq(udev_device_get_subsystem(dev), "block") && !supported_transport) {
free(path);
path = NULL;
}
const struct udev_builtin udev_builtin_path_id = {
.name = "path_id",
.cmd = builtin_path_id,
- .help = "compose persistent device path",
+ .help = "Compose persistent device path",
.run_once = true,
};