device: allow easy identification of network interfaces without their full sysfs device path

This commit is contained in:
Lennart Poettering 2010-05-10 04:08:53 +02:00
parent bab4504448
commit afb757b1a8
2 changed files with 33 additions and 3 deletions

View file

@ -19,7 +19,20 @@ ACTION!="add|change", GOTO="systemd_end"
KERNEL=="tty[0-9]|tty1[0-2]", ENV{SYSTEMD_EXPOSE}="1"
KERNEL=="ttyS*", ENV{SYSTEMD_EXPOSE}="1"
SUBSYSTEM=="block", ENV{SYSTEMD_EXPOSE}="1"
SUBSYSTEM=="net", ENV{SYSTEMD_EXPOSE}="1"
# We need a hardware independant way to identify network devices. We
# use the /sys/subsystem path for this. Current vanilla kernels don't
# actually support that hierarchy right now, however upcoming kernels
# will. HAL and udev internally support /sys/subsystem already, hence
# it should be safe to use this here, too. This is mostly just an
# identification string for systemd, so whether the path actually is
# accessible or not does not matter as long as it is unique and in the
# filesystem namespace.
#
# http://git.kernel.org/?p=linux/hotplug/udev.git;a=blob;f=libudev/libudev-enumerate.c;h=da831449dcaf5e936a14409e8e68ab12d30a98e2;hb=HEAD#l742
SUBSYSTEM=="net", KERNEL!="lo", ENV{SYSTEMD_EXPOSE}="1", ENV{SYSTEMD_ALIAS}="/sys/subsystem/net/devices/%k"
LABEL="systemd_end"

View file

@ -144,7 +144,7 @@ static int device_find_escape_name(Manager *m, const char *dn, Unit **_u) {
}
static int device_process_new_device(Manager *m, struct udev_device *dev, bool update_state) {
const char *dn, *wants, *sysfs, *expose, *model;
const char *dn, *wants, *sysfs, *expose, *model, *alias;
Unit *u = NULL;
int r;
char *w, *state;
@ -172,6 +172,15 @@ static int device_process_new_device(Manager *m, struct udev_device *dev, bool u
/* Check whether this entry is even relevant for us. */
dn = udev_device_get_devnode(dev);
wants = udev_device_get_property_value(dev, "SYSTEMD_WANTS");
alias = udev_device_get_property_value(dev, "SYSTEMD_ALIAS");
/* We allow exactly one alias to be configured a this time and
* it must be a path */
if (alias && !is_path(alias)) {
log_warning("SYSTEMD_ALIAS for %s is not a path, ignoring: %s", sysfs, alias);
alias = NULL;
}
if ((r = device_find_escape_name(m, sysfs, &u)) < 0)
return r;
@ -191,12 +200,16 @@ static int device_process_new_device(Manager *m, struct udev_device *dev, bool u
}
}
if (r == 0 && alias)
if ((r = device_find_escape_name(m, alias, &u)) < 0)
return r;
/* FIXME: this needs proper merging */
assert((r > 0) == !!u);
/* If this is a different unit, then let's not merge things */
if (u && DEVICE(u)->sysfs && !streq(DEVICE(u)->sysfs, sysfs))
if (u && DEVICE(u)->sysfs && !path_equal(DEVICE(u)->sysfs, sysfs))
u = NULL;
if (!u) {
@ -218,6 +231,10 @@ static int device_process_new_device(Manager *m, struct udev_device *dev, bool u
goto fail;
}
if (alias)
if ((r = device_add_escaped_name(u, alias, true)) < 0)
goto fail;
if (dn)
if ((r = device_add_escaped_name(u, dn, true)) < 0)
goto fail;