Existe uma maneira de alterar os nomes de dispositivos no diretório / dev?

13

Eu escrevi esta regra para fins de teste:

SUBSYSTEMS=="usb", ATTRS{manufacturer}=="Kingston", ATTRS{serial}=="001CC0EC34A2BB318709004B", ATTRS{idVendor}=="0951", ATTRS{idProduct}=="1642", SYMLINK+="pen", NAME="pendrak"

com base nas seguintes informações:

# udevadm info --name=/dev/sdb --attribute-walk

Udevadm info starts with the device specified by the devpath and then
walks up the chain of parent devices. It prints for every device
found, all possible attributes in the udev rules key format.
A rule to match, can be composed by the attributes of the device
and the attributes from one single parent device.

  looking at device '/devices/pci0000:00/0000:00:1d.7/usb2/2-5/2-5:1.0/host2/target2:0:0/2:0:0:0/block/sdb':
    KERNEL=="sdb"
    SUBSYSTEM=="block"
    DRIVER==""
    ATTR{ro}=="0"
    ATTR{size}=="30299520"
    ATTR{stat}=="     419        0     3352     1208        0        0        0        0        0     1120     1208"
    ATTR{range}=="16"
    ATTR{discard_alignment}=="0"
    ATTR{events}=="media_change"
    ATTR{ext_range}=="256"
    ATTR{events_poll_msecs}=="3000"
    ATTR{alignment_offset}=="0"
    ATTR{inflight}=="       0        0"
    ATTR{removable}=="1"
    ATTR{capability}=="51"
    ATTR{events_async}==""

  looking at parent device '/devices/pci0000:00/0000:00:1d.7/usb2/2-5/2-5:1.0/host2/target2:0:0/2:0:0:0':
    KERNELS=="2:0:0:0"
    SUBSYSTEMS=="scsi"
    DRIVERS=="sd"
    ATTRS{rev}=="PMAP"
    ATTRS{type}=="0"
    ATTRS{scsi_level}=="0"
    ATTRS{model}=="DT 101 G2       "
    ATTRS{state}=="running"
    ATTRS{queue_type}=="none"
    ATTRS{iodone_cnt}=="0x2da"
    ATTRS{iorequest_cnt}=="0x2da"
    ATTRS{evt_capacity_change_reported}=="0"
    ATTRS{timeout}=="30"
    ATTRS{evt_media_change}=="0"
    ATTRS{max_sectors}=="240"
    ATTRS{ioerr_cnt}=="0x2"
    ATTRS{queue_depth}=="1"
    ATTRS{vendor}=="Kingston"
    ATTRS{evt_soft_threshold_reached}=="0"
    ATTRS{device_blocked}=="0"
    ATTRS{evt_mode_parameter_change_reported}=="0"
    ATTRS{evt_lun_change_reported}=="0"
    ATTRS{evt_inquiry_change_reported}=="0"
    ATTRS{iocounterbits}=="32"
    ATTRS{eh_timeout}=="10"

  looking at parent device '/devices/pci0000:00/0000:00:1d.7/usb2/2-5/2-5:1.0/host2/target2:0:0':
    KERNELS=="target2:0:0"
    SUBSYSTEMS=="scsi"
    DRIVERS==""

  looking at parent device '/devices/pci0000:00/0000:00:1d.7/usb2/2-5/2-5:1.0/host2':
    KERNELS=="host2"
    SUBSYSTEMS=="scsi"
    DRIVERS==""

  looking at parent device '/devices/pci0000:00/0000:00:1d.7/usb2/2-5/2-5:1.0':
    KERNELS=="2-5:1.0"
    SUBSYSTEMS=="usb"
    DRIVERS=="usb-storage"
    ATTRS{bInterfaceClass}=="08"
    ATTRS{bInterfaceSubClass}=="06"
    ATTRS{bInterfaceProtocol}=="50"
    ATTRS{bNumEndpoints}=="02"
    ATTRS{supports_autosuspend}=="1"
    ATTRS{bAlternateSetting}==" 0"
    ATTRS{bInterfaceNumber}=="00"

  looking at parent device '/devices/pci0000:00/0000:00:1d.7/usb2/2-5':
    KERNELS=="2-5"
    SUBSYSTEMS=="usb"
    DRIVERS=="usb"
    ATTRS{bDeviceSubClass}=="00"
    ATTRS{bDeviceProtocol}=="00"
    ATTRS{devpath}=="5"
    ATTRS{idVendor}=="0951"
    ATTRS{speed}=="480"
    ATTRS{bNumInterfaces}==" 1"
    ATTRS{bConfigurationValue}=="1"
    ATTRS{bMaxPacketSize0}=="64"
    ATTRS{busnum}=="2"
    ATTRS{devnum}=="4"
    ATTRS{configuration}==""
    ATTRS{bMaxPower}=="200mA"
    ATTRS{authorized}=="1"
    ATTRS{bmAttributes}=="80"
    ATTRS{bNumConfigurations}=="1"
    ATTRS{maxchild}=="0"
    ATTRS{bcdDevice}=="0100"
    ATTRS{avoid_reset_quirk}=="0"
    ATTRS{quirks}=="0x0"
    ATTRS{serial}=="001CC0EC34A2BB318709004B"
    ATTRS{version}==" 2.00"
    ATTRS{urbnum}=="1927"
    ATTRS{ltm_capable}=="no"
    ATTRS{manufacturer}=="Kingston"
    ATTRS{removable}=="unknown"
    ATTRS{idProduct}=="1642"
    ATTRS{bDeviceClass}=="00"
    ATTRS{product}=="DT 101 G2"

  looking at parent device '/devices/pci0000:00/0000:00:1d.7/usb2':
    KERNELS=="usb2"
    SUBSYSTEMS=="usb"
    DRIVERS=="usb"
    ATTRS{bDeviceSubClass}=="00"
    ATTRS{bDeviceProtocol}=="00"
    ATTRS{devpath}=="0"
    ATTRS{idVendor}=="1d6b"
    ATTRS{speed}=="480"
    ATTRS{bNumInterfaces}==" 1"
    ATTRS{bConfigurationValue}=="1"
    ATTRS{bMaxPacketSize0}=="64"
    ATTRS{authorized_default}=="1"
    ATTRS{busnum}=="2"
    ATTRS{devnum}=="1"
    ATTRS{configuration}==""
    ATTRS{bMaxPower}=="0mA"
    ATTRS{authorized}=="1"
    ATTRS{bmAttributes}=="e0"
    ATTRS{bNumConfigurations}=="1"
    ATTRS{maxchild}=="8"
    ATTRS{bcdDevice}=="0312"
    ATTRS{avoid_reset_quirk}=="0"
    ATTRS{quirks}=="0x0"
    ATTRS{serial}=="0000:00:1d.7"
    ATTRS{version}==" 2.00"
    ATTRS{urbnum}=="89"
    ATTRS{ltm_capable}=="no"
    ATTRS{manufacturer}=="Linux 3.12-1-amd64 ehci_hcd"
    ATTRS{removable}=="unknown"
    ATTRS{idProduct}=="0002"
    ATTRS{bDeviceClass}=="09"
    ATTRS{product}=="EHCI Host Controller"

  looking at parent device '/devices/pci0000:00/0000:00:1d.7':
    KERNELS=="0000:00:1d.7"
    SUBSYSTEMS=="pci"
    DRIVERS=="ehci-pci"
    ATTRS{irq}=="23"
    ATTRS{subsystem_vendor}=="0x1458"
    ATTRS{broken_parity_status}=="0"
    ATTRS{class}=="0x0c0320"
    ATTRS{companion}==""
    ATTRS{consistent_dma_mask_bits}=="32"
    ATTRS{dma_mask_bits}=="32"
    ATTRS{local_cpus}=="00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000003"
    ATTRS{device}=="0x27cc"
    ATTRS{uframe_periodic_max}=="100"
    ATTRS{enable}=="1"
    ATTRS{msi_bus}==""
    ATTRS{local_cpulist}=="0-1"
    ATTRS{vendor}=="0x8086"
    ATTRS{subsystem_device}=="0x5006"
    ATTRS{numa_node}=="-1"
    ATTRS{d3cold_allowed}=="1"

  looking at parent device '/devices/pci0000:00':
    KERNELS=="pci0000:00"
    SUBSYSTEMS==""
    DRIVERS==""

e:

# udevadm info --name=/dev/sdb
P: /devices/pci0000:00/0000:00:1d.7/usb2/2-5/2-5:1.0/host2/target2:0:0/2:0:0:0/block/sdb
N: sdb
S: disk/by-id/usb-Kingston_DT_101_G2_001CC0EC34A2BB318709004B-0:0
S: disk/by-path/pci-0000:00:1d.7-usb-0:5:1.0-scsi-0:0:0:0
S: pen
E: DEVLINKS=/dev/disk/by-id/usb-Kingston_DT_101_G2_001CC0EC34A2BB318709004B-0:0 /dev/disk/by-path/pci-0000:00:1d.7-usb-0:5:1.0-scsi-0:0:0:0 /dev/pen
E: DEVNAME=/dev/sdb
E: DEVPATH=/devices/pci0000:00/0000:00:1d.7/usb2/2-5/2-5:1.0/host2/target2:0:0/2:0:0:0/block/sdb
E: DEVTYPE=disk
E: ID_BUS=usb
E: ID_INSTANCE=0:0
E: ID_MODEL=DT_101_G2
E: ID_MODEL_ENC=DT\x20101\x20G2\x20\x20\x20\x20\x20\x20\x20
E: ID_MODEL_ID=1642
E: ID_PART_TABLE_TYPE=dos
E: ID_PATH=pci-0000:00:1d.7-usb-0:5:1.0-scsi-0:0:0:0
E: ID_PATH_TAG=pci-0000_00_1d_7-usb-0_5_1_0-scsi-0_0_0_0
E: ID_REVISION=PMAP
E: ID_SERIAL=Kingston_DT_101_G2_001CC0EC34A2BB318709004B-0:0
E: ID_SERIAL_SHORT=001CC0EC34A2BB318709004B
E: ID_TYPE=disk
E: ID_USB_DRIVER=usb-storage
E: ID_USB_INTERFACES=:080650:
E: ID_USB_INTERFACE_NUM=00
E: ID_VENDOR=Kingston
E: ID_VENDOR_ENC=Kingston
E: ID_VENDOR_ID=0951
E: MAJOR=8
E: MINOR=16
E: SUBSYSTEM=block
E: USEC_INITIALIZED=32380484

Mas quando eu queria testá-lo, ele me deu este log:

# udevadm test /devices/pci0000:00/0000:00:1d.7/usb2/2-5/2-5:1.0/host2/target2:0:0/2:0:0:0/block/sdb
calling: test
version 204
This program is for debugging only, it does not run any program
specified by a RUN key. It may show incorrect results, because
some values may be different, or not available at a simulation run.

=== trie on-disk ===
tool version:          204
file size:         5729797 bytes
header size             80 bytes
strings            1262125 bytes
nodes              4467592 bytes
load module index
Skipping overridden file: /lib/udev/rules.d/95-keymap.rules.
read rules file: /lib/udev/rules.d/42-usb-hid-pm.rules
read rules file: /lib/udev/rules.d/50-firmware.rules
read rules file: /lib/udev/rules.d/50-udev-default.rules
read rules file: /lib/udev/rules.d/55-dm.rules
read rules file: /lib/udev/rules.d/56-lvm.rules
read rules file: /lib/udev/rules.d/60-cdrom_id.rules
read rules file: /lib/udev/rules.d/60-fuse.rules
read rules file: /lib/udev/rules.d/60-gnupg.rules
read rules file: /lib/udev/rules.d/60-libfreenect0.2.rules
read rules file: /lib/udev/rules.d/60-libgphoto2-6.rules
read rules file: /lib/udev/rules.d/60-libpisock9.rules
read rules file: /lib/udev/rules.d/60-libsane.rules
read rules file: /lib/udev/rules.d/60-nvidia-kernel-common.rules
read rules file: /lib/udev/rules.d/60-pcmcia.rules
read rules file: /lib/udev/rules.d/60-persistent-alsa.rules
read rules file: /lib/udev/rules.d/60-persistent-input.rules
read rules file: /lib/udev/rules.d/60-persistent-serial.rules
read rules file: /lib/udev/rules.d/60-persistent-storage-dm.rules
read rules file: /lib/udev/rules.d/60-persistent-storage-tape.rules
read rules file: /lib/udev/rules.d/60-persistent-storage.rules
read rules file: /lib/udev/rules.d/60-persistent-v4l.rules
read rules file: /lib/udev/rules.d/60-virtualbox-dkms.rules
read rules file: /lib/udev/rules.d/60-virtualbox.rules
read rules file: /lib/udev/rules.d/61-accelerometer.rules
read rules file: /etc/udev/rules.d/61-removable-storage-polling.rules
read rules file: /lib/udev/rules.d/64-btrfs.rules
read rules file: /lib/udev/rules.d/64-xorg-xkb.rules
read rules file: /lib/udev/rules.d/69-cd-sensors.rules
IMPORT found builtin 'usb_id --export %p', replacing /lib/udev/rules.d/69-cd-sensors.rules:89
read rules file: /lib/udev/rules.d/69-libmtp.rules
read rules file: /lib/udev/rules.d/69-lvm-metad.rules
read rules file: /lib/udev/rules.d/69-xorg-vmmouse.rules
read rules file: /lib/udev/rules.d/70-btrfs.rules
read rules file: /etc/udev/rules.d/70-persistent-cd.rules
read rules file: /etc/udev/rules.d/70-persistent-net.rules
read rules file: /lib/udev/rules.d/70-power-switch.rules
read rules file: /lib/udev/rules.d/70-udev-acl.rules
read rules file: /etc/udev/rules.d/70-zram.rules
read rules file: /lib/udev/rules.d/75-cd-aliases-generator.rules
read rules file: /lib/udev/rules.d/75-net-description.rules
read rules file: /lib/udev/rules.d/75-persistent-net-generator.rules
read rules file: /lib/udev/rules.d/75-probe_mtd.rules
read rules file: /lib/udev/rules.d/75-tty-description.rules
read rules file: /lib/udev/rules.d/78-sound-card.rules
read rules file: /lib/udev/rules.d/80-btrfs-lvm.rules
read rules file: /lib/udev/rules.d/80-drivers.rules
read rules file: /lib/udev/rules.d/80-net-name-slot.rules
read rules file: /lib/udev/rules.d/80-networking.rules
read rules file: /lib/udev/rules.d/85-hdparm.rules
read rules file: /lib/udev/rules.d/85-hwclock.rules
read rules file: /lib/udev/rules.d/90-alsa-restore.rules
read rules file: /lib/udev/rules.d/90-pulseaudio.rules
read rules file: /lib/udev/rules.d/91-permissions.rules
read rules file: /lib/udev/rules.d/95-cd-devices.rules
read rules file: /lib/udev/rules.d/95-keyboard-force-release.rules
read rules file: /etc/udev/rules.d/95-keymap.rules
read rules file: /lib/udev/rules.d/95-udev-late.rules
read rules file: /lib/udev/rules.d/97-bluetooth-hid2hci.rules
read rules file: /etc/udev/rules.d/99-local.rules
rules contain 393216 bytes tokens (32768 * 12 bytes), 31233 bytes strings
27768 strings (226512 bytes), 24687 de-duplicated (198361 bytes), 3082 trie nodes used
IMPORT builtin 'usb_id' /lib/udev/rules.d/60-persistent-storage.rules:68
/sys/devices/pci0000:00/0000:00:1d.7/usb2/2-5/2-5:1.0: if_class 8 protocol 6
IMPORT builtin 'path_id' /lib/udev/rules.d/60-persistent-storage.rules:89
LINK 'disk/by-id/usb-Kingston_DT_101_G2_001CC0EC34A2BB318709004B-0:0' /lib/udev/rules.d/60-persistent-storage.rules:108
LINK 'disk/by-path/pci-0000:00:1d.7-usb-0:5:1.0-scsi-0:0:0:0' /lib/udev/rules.d/60-persistent-storage.rules:130
IMPORT '/sbin/blkid -o udev -p /dev/sdb' /lib/udev/rules.d/60-persistent-storage.rules:151
starting '/sbin/blkid -o udev -p /dev/sdb'
'/sbin/blkid -o udev -p /dev/sdb' [12103] exit with return code 0
RUN '/etc/init.d/hdparm hotplug' /lib/udev/rules.d/85-hdparm.rules:1
GROUP 6 /lib/udev/rules.d/91-permissions.rules:4
GROUP 25 /lib/udev/rules.d/91-permissions.rules:5
GROUP 25 /lib/udev/rules.d/91-permissions.rules:9
NAME="pendrak" ignored, kernel device nodes can not be renamed; please fix it in /etc/udev/rules.d/99-local.rules:1
LINK 'pen' /etc/udev/rules.d/99-local.rules:1
handling device node '/dev/sdb', devnum=b8:16, mode=0660, uid=0, gid=25
preserve permissions /dev/sdb, 060660, uid=0, gid=25
preserve already existing symlink '/dev/block/8:16' to '../sdb'
found 'b8:16' claiming '/run/udev/links/\x2fdisk\x2fby-id\x2fusb-Kingston_DT_101_G2_001CC0EC34A2BB318709004B-0:0'
creating link '/dev/disk/by-id/usb-Kingston_DT_101_G2_001CC0EC34A2BB318709004B-0:0' to '/dev/sdb'
preserve already existing symlink '/dev/disk/by-id/usb-Kingston_DT_101_G2_001CC0EC34A2BB318709004B-0:0' to '../../sdb'
found 'b8:16' claiming '/run/udev/links/\x2fdisk\x2fby-path\x2fpci-0000:00:1d.7-usb-0:5:1.0-scsi-0:0:0:0'
creating link '/dev/disk/by-path/pci-0000:00:1d.7-usb-0:5:1.0-scsi-0:0:0:0' to '/dev/sdb'
preserve already existing symlink '/dev/disk/by-path/pci-0000:00:1d.7-usb-0:5:1.0-scsi-0:0:0:0' to '../../sdb'
found 'b8:16' claiming '/run/udev/links/\x2fpen'
creating link '/dev/pen' to '/dev/sdb'
preserve already existing symlink '/dev/pen' to 'sdb'
.ID_FS_TYPE_NEW=
ACTION=add
DEVLINKS=/dev/disk/by-id/usb-Kingston_DT_101_G2_001CC0EC34A2BB318709004B-0:0 /dev/disk/by-path/pci-0000:00:1d.7-usb-0:5:1.0-scsi-0:0:0:0 /dev/pen
DEVNAME=/dev/sdb
DEVPATH=/devices/pci0000:00/0000:00:1d.7/usb2/2-5/2-5:1.0/host2/target2:0:0/2:0:0:0/block/sdb
DEVTYPE=disk
ID_BUS=usb
ID_FS_TYPE=
ID_INSTANCE=0:0
ID_MODEL=DT_101_G2
ID_MODEL_ENC=DT\x20101\x20G2\x20\x20\x20\x20\x20\x20\x20
ID_MODEL_ID=1642
ID_PART_TABLE_TYPE=dos
ID_PATH=pci-0000:00:1d.7-usb-0:5:1.0-scsi-0:0:0:0
ID_PATH_TAG=pci-0000_00_1d_7-usb-0_5_1_0-scsi-0_0_0_0
ID_REVISION=PMAP
ID_SERIAL=Kingston_DT_101_G2_001CC0EC34A2BB318709004B-0:0
ID_SERIAL_SHORT=001CC0EC34A2BB318709004B
ID_TYPE=disk
ID_USB_DRIVER=usb-storage
ID_USB_INTERFACES=:080650:
ID_USB_INTERFACE_NUM=00
ID_VENDOR=Kingston
ID_VENDOR_ENC=Kingston
ID_VENDOR_ID=0951
MAJOR=8
MINOR=16
SUBSYSTEM=block
USEC_INITIALIZED=32380484
run: '/etc/init.d/hdparm hotplug'
unload module index

E como você pode ver, o link simbólico é criado, mas o nome não mudou e eu recebi o seguinte erro:

NAME="pendrak" ignored, kernel device nodes can not be renamed; please fix it in /etc/udev/rules.d/99-local.rules:1

A outra coisa é que o link aponta aleatoriamente para sdb, sdb1, sdb2, etc:

# ls -al /dev/pen
lrwxrwxrwx 1 root root 3 Mar 13 12:49 /dev/pen -> sdb
# ls -al /dev/pen
lrwxrwxrwx 1 root root 4 Mar 13 12:53 /dev/pen -> sdb2
# ls -al /dev/pen
lrwxrwxrwx 1 root root 4 Mar 13 12:53 /dev/pen -> sdb1
# ls -al /dev/pen
lrwxrwxrwx 1 root root 4 Mar 13 12:53 /dev/pen -> sdb2
# ls -al /dev/pen
lrwxrwxrwx 1 root root 4 Mar 13 12:53 /dev/pen -> sdb3

Ele muda toda vez que eu conecto o pendrive.

A tarefa aqui é alterar o nome do dispositivo de sdb (ou o que quer que seja) para pendrake também criar um link para ele. O erro alegava que "nós de dispositivos do kernel não podem ser renomeados" - significa que não consigo alterar o nome e tudo o que posso fazer é criar links simbólicos?

devices udev Mikhail Morfikov
fonte

Respostas:

14

De acordo com o manual do udev, não há como alterar os nomes dos arquivos no /dev/diretório:

NAME
The name to use for a network interface. The name of a device node
cannot be changed by udev, only additional symlinks can be created.

Então, no meu caso, eu deveria escrever regras semelhantes a estas:

KERNEL=="sd?3", ACTION=="add", ENV{ID_SERIAL_SHORT}=="001CC0EC34A2BB318709004B", \
    SYMLINK+="pen%n", \
    RUN+="/usr/bin/udevil mount /dev/pen%n /mnt/dane"

KERNEL=="sd?1", ACTION=="add", ENV{ID_SERIAL_SHORT}=="001CC0EC34A2BB318709004B", \
    SYMLINK+="pen%n", \
    RUN+="/usr/bin/udevil mount /dev/pen%n /mnt/debian"

KERNEL=="sd?2", ACTION=="add", ENV{ID_SERIAL_SHORT}=="001CC0EC34A2BB318709004B", \
    SYMLINK+="pen%n", \
    RUN+="/sbin/cryptsetup luksOpen /dev/pen%n pen%n --key-file=/home/morfik/Desktop/pen2.key", \
    RUN+="/usr/bin/udevil mount /dev/mapper/pen%n /mnt/szyfr"
KERNEL=="sd?2", ACTION=="remove", ENV{ID_SERIAL_SHORT}=="001CC0EC34A2BB318709004B", \
    RUN+="/sbin/cryptsetup luksClose pen%n"

Eles criam três links: pen1, pen2, pen3. Cada um dos quais se vincula ao dispositivo sdb correspondente (ou seja lá o que for), e simplesmente os abre e monta nos diretórios especificados por meio da ferramenta udevil.

Mikhail Morfikov
fonte
Que tal wiki.archlinux.org/index.php/…
orion
2
Isso se aplica apenas a interfaces de rede, como você pode ler na resposta.
Mikhail Morfikov 18/03/2014
1
Nota: isso também funcionava com outros tipos de dispositivos, mas esse recurso foi removido em algumas versões do systemd.
Ola5041
Se não podemos mais renomear nós de dispositivos do kernel, existem soluções alternativas? Alguma maneira de força bruta? : D
midnite
Basta criar links simbólicos. Estou fazendo isso para todos os dispositivos que precisam ter o mesmo nome, não importa o quê.
Mikhail Morfikov