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mirror of https://github.com/systemd/systemd-stable.git synced 2024-10-30 23:21:08 +03:00
systemd-stable/udev-remove.c
kay.sievers@vrfy.org f61d732a02 [PATCH] hmm, handle net devices with udev?
Hmm, Arndt Bergmann sent a patch like this one a few weeks ago and
I want to bring the question back, if we want to handle net device
naming with udev.

With this patch it is actually possible to specify something like this
in udev.rules:

  KERNEL="dummy*", SYSFS{address}="00:00:00:00:00:00", SYSFS{features}="0x0", NAME="blind%n"
  KERNEL="eth*", SYSFS{address}="00:0d:60:77:30:91", NAME="private"

and you will get:

  [root@pim udev.kay]# cat /proc/net/dev
  Inter-|   Receive                                                | Transmit
   face |bytes    packets errs drop fifo frame compressed multicast|bytes   packets errs drop fifo colls carrier compressed
       lo:    1500     30    0    0    0     0          0         0    1500      30    0    0    0     0       0          0
  private:  278393   1114    0    0    0     0          0         0  153204    1468    0    0    0     0       0          0
     sit0:       0      0    0    0    0     0          0         0       0       0    0    0    0     0       0          0
   blind0:       0      0    0    0    0     0          0         0       0       0    0    0    0     0       0          0


The udevinfo program is also working:

  [root@pim udev.kay]# ./udevinfo -a -p /sys/class/net/private
    looking at class device '/sys/class/net/private':
      SYSFS{addr_len}="6"
      SYSFS{address}="00:0d:60:77:30:91"
      SYSFS{broadcast}="ff:ff:ff:ff:ff:ff"
      SYSFS{features}="0x3a9"
      SYSFS{flags}="0x1003"
      SYSFS{ifindex}="2"
      SYSFS{iflink}="2"
      SYSFS{mtu}="1500"
      SYSFS{tx_queue_len}="1000"
      SYSFS{type}="1"

  follow the class device's "device"
    looking at the device chain at '/sys/devices/pci0000:00/0000:00:1e.0/0000:02:01.0':
      BUS="pci"
      ID="0000:02:01.0"
      SYSFS{class}="0x020000"
      SYSFS{detach_state}="0"
      SYSFS{device}="0x101e"
      SYSFS{irq}="11"
      SYSFS{subsystem_device}="0x0549"
      SYSFS{subsystem_vendor}="0x1014"
      SYSFS{vendor}="0x8086"


The matching device will be renamed to the given name. The device name
will not be put into the udev database, cause the kernel renames the
device and the sysfs name disappears.

I like it, cause it plugs in nicely. We have all the naming features
and sysfs queries and walks inside of  udev. The sysfs timing races
are already solved and the management tools are working for net devices
too. nameif can only match the MAC address now. udev can match any sysfs
value of the device tree the net device is connected to.
But right, net devices do not have device nodes :)
2005-04-26 21:35:12 -07:00

173 lines
3.7 KiB
C

/*
* udev-remove.c
*
* Userspace devfs
*
* Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
*
*
* 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 version 2 of the License.
*
* 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, write to the Free Software Foundation, Inc.,
* 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
#include "udev.h"
#include "udev_lib.h"
#include "udev_version.h"
#include "logging.h"
#include "namedev.h"
#include "udevdb.h"
static int delete_path(char *path)
{
char *pos;
int retval;
pos = strrchr(path, '/');
while (1) {
*pos = '\0';
pos = strrchr(path, '/');
/* don't remove the last one */
if ((pos == path) || (pos == NULL))
break;
/* remove if empty */
retval = rmdir(path);
if (errno == ENOENT)
retval = 0;
if (retval) {
if (errno == ENOTEMPTY)
return 0;
dbg("rmdir(%s) failed with error '%s'",
path, strerror(errno));
break;
}
dbg("removed '%s'", path);
}
return 0;
}
static int delete_node(struct udevice *dev)
{
char filename[NAME_SIZE];
char linkname[NAME_SIZE];
char partitionname[NAME_SIZE];
int retval;
int i;
char *pos;
int len;
strfieldcpy(filename, udev_root);
strfieldcat(filename, dev->name);
info("removing device node '%s'", filename);
retval = unlink(filename);
if (errno == ENOENT)
retval = 0;
if (retval) {
dbg("unlink(%s) failed with error '%s'",
filename, strerror(errno));
return retval;
}
/* remove partition nodes */
if (dev->partitions > 0) {
info("removing partitions '%s[1-%i]'", filename, dev->partitions);
for (i = 1; i <= dev->partitions; i++) {
strfieldcpy(partitionname, filename);
strintcat(partitionname, i);
unlink(partitionname);
}
}
/* remove subdirectories */
if (strchr(dev->name, '/'))
delete_path(filename);
foreach_strpart(dev->symlink, " ", pos, len) {
strfieldcpymax(linkname, pos, len+1);
strfieldcpy(filename, udev_root);
strfieldcat(filename, linkname);
dbg("unlinking symlink '%s'", filename);
retval = unlink(filename);
if (errno == ENOENT)
retval = 0;
if (retval) {
dbg("unlink(%s) failed with error '%s'",
filename, strerror(errno));
return retval;
}
if (strchr(dev->symlink, '/')) {
delete_path(filename);
}
}
return retval;
}
/*
* Look up the sysfs path in the database to see if we have named this device
* something different from the kernel name. If we have, us it. If not, use
* the default kernel name for lack of anything else to know to do.
*/
int udev_remove_device(char *path, char *subsystem)
{
struct udevice dev;
char *temp;
int retval;
memset(&dev, 0x00, sizeof(dev));
dev.type = get_device_type(path, subsystem);
switch (dev.type) {
case 'b':
case 'c':
retval = udevdb_get_dev(path, &dev);
if (retval) {
dbg("'%s' not found in database, falling back on default name", path);
temp = strrchr(path, '/');
if (temp == NULL)
return -ENODEV;
strfieldcpy(dev.name, &temp[1]);
}
dbg("name='%s'", dev.name);
udevdb_delete_dev(path);
dev_d_send(&dev, subsystem);
retval = delete_node(&dev);
break;
case 'n':
retval = 0;
break;
default:
dbg("unknown device type '%c'", dev.type);
retval = -EINVAL;
}
return retval;
}