[Buildroot] [PATCH 1/3] Create menu entry to select device creation method

[Buildroot] [PATCH 1/3] Create menu entry to select device creation method

[Thomas Petazzoni]

From: Yegor Yefremov <yegor_sub1@visionsystems.de>

Four methods for the creation of device files in /dev are now
proposed:

 - static method uses device table as before
 - devtmpfs method enables this feature in kernel
 - mdev method adds mdev starting script to the file system
    and selects mdev itself for installation
 - udev method selects udev for installation

All dynamic methods are based on devtmpfs, so one doesn't need to care
about /dev folder.

Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
---
 fs/Config.in               |   33 +++++++++++++++++++++++++++------
 linux/linux.mk             |    7 +++++++
 package/busybox/S10mdev    |   22 ++++++++++++++++++++++
 package/busybox/busybox.mk |   15 +++++++++++++++
 4 files changed, 71 insertions(+), 6 deletions(-)
 create mode 100644 package/busybox/S10mdev

diff --git a/fs/Config.in b/fs/Config.in
index 188e815..9ac3acc 100644
--- a/fs/Config.in
+++ b/fs/Config.in
@@ -15,13 +15,34 @@ config BR2_ROOTFS_POST_BUILD_SCRIPT
 	  only argument. Make sure the exit code of that script is 0,
 	  otherwise make will stop after calling it.
 
+choice
+	prompt "/dev management"
+	default BR2_ROOTFS_DEVICE_CREATION_STATIC
+
+config BR2_ROOTFS_DEVICE_CREATION_STATIC
+	bool "Static using device table"
+
+config BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_DEVTMPFS
+	bool "Dynamic using devtmpfs only"
+
+config BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_MDEV
+	bool "Dynamic using mdev"
+	select BR2_PACKAGE_BUSYBOX
+
+config BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_UDEV
+	bool "Dynamic using udev"
+	select BR2_PACKAGE_UDEV
+
+endchoice
+
 config BR2_ROOTFS_DEVICE_TABLE
-       string "Path to the device table"
-       default "target/generic/device_table.txt"
-       help
-         Specify the location of a device table, that will be passed
-         to the makedevs utility to create all the special device
-         files in the target filesystem.
+	string "Path to the device table"
+	depends on BR2_ROOTFS_DEVICE_CREATION_STATIC
+	default "target/generic/device_table.txt"
+	help
+	  Specify the location of a device table, that will be passed
+	  to the makedevs utility to create all the special device
+	  files in the target filesystem.
 
 choice
 	prompt "Root FS skeleton"
diff --git a/linux/linux.mk b/linux/linux.mk
index 9076fb9..873a9e0 100644
--- a/linux/linux.mk
+++ b/linux/linux.mk
@@ -130,6 +130,13 @@ ifeq ($(BR2_TARGET_ROOTFS_INITRAMFS),y)
 	$(call KCONFIG_DISABLE_OPT,CONFIG_INITRAMFS_COMPRESSION_NONE,$(@D)/.config)
 	$(call KCONFIG_ENABLE_OPT,CONFIG_INITRAMFS_COMPRESSION_GZIP,$(@D)/.config)
 endif
+ifneq ($(BR2_ROOTFS_DEVICE_CREATION_STATIC),y)
+	$(call KCONFIG_ENABLE_OPT,CONFIG_DEVTMPFS,$(@D)/.config)
+	$(call KCONFIG_ENABLE_OPT,CONFIG_DEVTMPFS_MOUNT,$(@D)/.config)
+endif
+ifeq ($(BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_MDEV),y)
+	$(call KCONFIG_SET_OPT,CONFIG_UEVENT_HELPER_PATH,\"/sbin/mdev\",$(@D)/.config)
+endif
 	$(TARGET_MAKE_ENV) $(MAKE) $(LINUX26_MAKE_FLAGS) -C $(@D) oldconfig
 	$(Q)touch $@
 
diff --git a/package/busybox/S10mdev b/package/busybox/S10mdev
new file mode 100644
index 0000000..472810b
--- /dev/null
+++ b/package/busybox/S10mdev
@@ -0,0 +1,22 @@
+#!/bin/sh
+#
+# Start mdev....
+#
+
+case "$1" in
+  start)
+ 	echo "Starting mdev..."
+	/sbin/mdev -s
+	;;
+  stop)
+	;;
+  restart|reload)
+	;;
+  *)
+	echo $"Usage: $0 {start|stop|restart}"
+	exit 1
+esac
+
+exit $?
+
+
diff --git a/package/busybox/busybox.mk b/package/busybox/busybox.mk
index 5583bc6..2a1b839 100644
--- a/package/busybox/busybox.mk
+++ b/package/busybox/busybox.mk
@@ -28,6 +28,19 @@ ifndef BUSYBOX_CONFIG_FILE
 	BUSYBOX_CONFIG_FILE = $(call qstrip,$(BR2_PACKAGE_BUSYBOX_CONFIG))
 endif
 
+# If mdev will be used for device creation enable it and copy S10mdev to /etc/init.d
+ifeq ($(BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_MDEV),y)
+define BUSYBOX_INSTALL_MDEV_SCRIPT
+	install -m 0755 package/busybox/S10mdev $(TARGET_DIR)/etc/init.d
+endef
+define BUSYBOX_SET_MDEV
+	$(call KCONFIG_ENABLE_OPT,CONFIG_MDEV,$(BUSYBOX_BUILD_CONFIG))
+	$(call KCONFIG_ENABLE_OPT,CONFIG_FEATURE_MDEV_CONF,$(BUSYBOX_BUILD_CONFIG))
+	$(call KCONFIG_ENABLE_OPT,CONFIG_FEATURE_MDEV_EXEC,$(BUSYBOX_BUILD_CONFIG))
+	$(call KCONFIG_ENABLE_OPT,CONFIG_FEATURE_MDEV_LOAD_FIRMWARE,$(BUSYBOX_BUILD_CONFIG))
+endef
+endif
+
 # If we have external syslogd, force busybox to use it
 ifeq ($(BR2_PACKAGE_SYSKLOGD),y)
 define BUSYBOX_SET_SYSKLOGD
@@ -122,6 +135,7 @@ define BUSYBOX_CONFIGURE_CMDS
 	$(BUSYBOX_SET_IPV6)
 	$(BUSYBOX_SET_RPC)
 	$(BUSYBOX_PREFER_STATIC)
+	$(BUSYBOX_SET_MDEV)
 	$(BUSYBOX_NETKITBASE)
 	$(BUSYBOX_NETKITTELNET)
 	@yes "" | $(MAKE) ARCH=$(KERNEL_ARCH) CROSS_COMPILE="$(TARGET_CROSS)" \
@@ -138,6 +152,7 @@ define BUSYBOX_INSTALL_TARGET_CMDS
 		$(INSTALL) -m 0755 -D package/busybox/udhcpc.script \
 			$(TARGET_DIR)/usr/share/udhcpc/default.script; \
 	fi
+	$(BUSYBOX_INSTALL_MDEV_SCRIPT)
 endef
 
 define BUSYBOX_UNINSTALL_TARGET_CMDS
-- 
1.7.0.4

[Buildroot] [pull request] Pull request for branch for-2011.05/dev-handling

[Thomas Petazzoni]

The following changes since commit 0a70aa0cc5d0980e72677869d9d87e0e4e35e483:

  webkit: bump to version 1.2.7 (2011-03-31 15:23:13 +0200)

are available in the git repository at:
  git://git.busybox.net/~tpetazzoni/git/buildroot for-2011.05/dev-handling

Thomas Petazzoni (2):
      Simplify udev startup script
      Allow several device tables and split in two parts our device table

Yegor Yefremov (1):
      Create menu entry to select device creation method

 fs/Config.in                        |   41 +++++++-
 fs/common.mk                        |   14 ++-
 linux/linux.mk                      |    7 ++
 package/busybox/S10mdev             |   22 ++++
 package/busybox/busybox.mk          |   15 +++
 package/makedevs/README             |   35 +++++++
 package/udev/S10udev                |   34 -------
 target/generic/device_table.txt     |  186 ++--------------------------------
 target/generic/device_table_dev.txt |  142 ++++++++++++++++++++++++++
 9 files changed, 276 insertions(+), 220 deletions(-)
 create mode 100644 package/busybox/S10mdev
 create mode 100644 package/makedevs/README
 create mode 100644 target/generic/device_table_dev.txt

Thanks,
-- 
Thomas Petazzoni

[Buildroot] [PATCH 1/3] Create menu entry to select device creation method

[Thomas Petazzoni]

From: Yegor Yefremov <yegor_sub1@visionsystems.de>

Four methods for the creation of device files in /dev are now
proposed:

 - static method uses device table as before
 - devtmpfs method enables this feature in kernel
 - mdev method adds mdev starting script to the file system
    and selects mdev itself for installation
 - udev method selects udev for installation

All dynamic methods are based on devtmpfs, so one doesn't need to care
about /dev folder.

Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
---
 fs/Config.in               |   33 +++++++++++++++++++++++++++------
 linux/linux.mk             |    7 +++++++
 package/busybox/S10mdev    |   22 ++++++++++++++++++++++
 package/busybox/busybox.mk |   15 +++++++++++++++
 4 files changed, 71 insertions(+), 6 deletions(-)
 create mode 100644 package/busybox/S10mdev

diff --git a/fs/Config.in b/fs/Config.in
index 188e815..9ac3acc 100644
--- a/fs/Config.in
+++ b/fs/Config.in
@@ -15,13 +15,34 @@ config BR2_ROOTFS_POST_BUILD_SCRIPT
 	  only argument. Make sure the exit code of that script is 0,
 	  otherwise make will stop after calling it.
 
+choice
+	prompt "/dev management"
+	default BR2_ROOTFS_DEVICE_CREATION_STATIC
+
+config BR2_ROOTFS_DEVICE_CREATION_STATIC
+	bool "Static using device table"
+
+config BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_DEVTMPFS
+	bool "Dynamic using devtmpfs only"
+
+config BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_MDEV
+	bool "Dynamic using mdev"
+	select BR2_PACKAGE_BUSYBOX
+
+config BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_UDEV
+	bool "Dynamic using udev"
+	select BR2_PACKAGE_UDEV
+
+endchoice
+
 config BR2_ROOTFS_DEVICE_TABLE
-       string "Path to the device table"
-       default "target/generic/device_table.txt"
-       help
-         Specify the location of a device table, that will be passed
-         to the makedevs utility to create all the special device
-         files in the target filesystem.
+	string "Path to the device table"
+	depends on BR2_ROOTFS_DEVICE_CREATION_STATIC
+	default "target/generic/device_table.txt"
+	help
+	  Specify the location of a device table, that will be passed
+	  to the makedevs utility to create all the special device
+	  files in the target filesystem.
 
 choice
 	prompt "Root FS skeleton"
diff --git a/linux/linux.mk b/linux/linux.mk
index 9076fb9..873a9e0 100644
--- a/linux/linux.mk
+++ b/linux/linux.mk
@@ -130,6 +130,13 @@ ifeq ($(BR2_TARGET_ROOTFS_INITRAMFS),y)
 	$(call KCONFIG_DISABLE_OPT,CONFIG_INITRAMFS_COMPRESSION_NONE,$(@D)/.config)
 	$(call KCONFIG_ENABLE_OPT,CONFIG_INITRAMFS_COMPRESSION_GZIP,$(@D)/.config)
 endif
+ifneq ($(BR2_ROOTFS_DEVICE_CREATION_STATIC),y)
+	$(call KCONFIG_ENABLE_OPT,CONFIG_DEVTMPFS,$(@D)/.config)
+	$(call KCONFIG_ENABLE_OPT,CONFIG_DEVTMPFS_MOUNT,$(@D)/.config)
+endif
+ifeq ($(BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_MDEV),y)
+	$(call KCONFIG_SET_OPT,CONFIG_UEVENT_HELPER_PATH,\"/sbin/mdev\",$(@D)/.config)
+endif
 	$(TARGET_MAKE_ENV) $(MAKE) $(LINUX26_MAKE_FLAGS) -C $(@D) oldconfig
 	$(Q)touch $@
 
diff --git a/package/busybox/S10mdev b/package/busybox/S10mdev
new file mode 100644
index 0000000..472810b
--- /dev/null
+++ b/package/busybox/S10mdev
@@ -0,0 +1,22 @@
+#!/bin/sh
+#
+# Start mdev....
+#
+
+case "$1" in
+  start)
+ 	echo "Starting mdev..."
+	/sbin/mdev -s
+	;;
+  stop)
+	;;
+  restart|reload)
+	;;
+  *)
+	echo $"Usage: $0 {start|stop|restart}"
+	exit 1
+esac
+
+exit $?
+
+
diff --git a/package/busybox/busybox.mk b/package/busybox/busybox.mk
index ffd6667..711d11b 100644
--- a/package/busybox/busybox.mk
+++ b/package/busybox/busybox.mk
@@ -28,6 +28,19 @@ ifndef BUSYBOX_CONFIG_FILE
 	BUSYBOX_CONFIG_FILE = $(call qstrip,$(BR2_PACKAGE_BUSYBOX_CONFIG))
 endif
 
+# If mdev will be used for device creation enable it and copy S10mdev to /etc/init.d
+ifeq ($(BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_MDEV),y)
+define BUSYBOX_INSTALL_MDEV_SCRIPT
+	install -m 0755 package/busybox/S10mdev $(TARGET_DIR)/etc/init.d
+endef
+define BUSYBOX_SET_MDEV
+	$(call KCONFIG_ENABLE_OPT,CONFIG_MDEV,$(BUSYBOX_BUILD_CONFIG))
+	$(call KCONFIG_ENABLE_OPT,CONFIG_FEATURE_MDEV_CONF,$(BUSYBOX_BUILD_CONFIG))
+	$(call KCONFIG_ENABLE_OPT,CONFIG_FEATURE_MDEV_EXEC,$(BUSYBOX_BUILD_CONFIG))
+	$(call KCONFIG_ENABLE_OPT,CONFIG_FEATURE_MDEV_LOAD_FIRMWARE,$(BUSYBOX_BUILD_CONFIG))
+endef
+endif
+
 # If we have external syslogd, force busybox to use it
 ifeq ($(BR2_PACKAGE_SYSKLOGD),y)
 define BUSYBOX_SET_SYSKLOGD
@@ -122,6 +135,7 @@ define BUSYBOX_CONFIGURE_CMDS
 	$(BUSYBOX_SET_IPV6)
 	$(BUSYBOX_SET_RPC)
 	$(BUSYBOX_PREFER_STATIC)
+	$(BUSYBOX_SET_MDEV)
 	$(BUSYBOX_NETKITBASE)
 	$(BUSYBOX_NETKITTELNET)
 	@yes "" | $(MAKE) ARCH=$(KERNEL_ARCH) CROSS_COMPILE="$(TARGET_CROSS)" \
@@ -138,6 +152,7 @@ define BUSYBOX_INSTALL_TARGET_CMDS
 		$(INSTALL) -m 0755 -D package/busybox/udhcpc.script \
 			$(TARGET_DIR)/usr/share/udhcpc/default.script; \
 	fi
+	$(BUSYBOX_INSTALL_MDEV_SCRIPT)
 endef
 
 define BUSYBOX_UNINSTALL_TARGET_CMDS
-- 
1.7.1

[Buildroot] [PATCH 2/3] Simplify udev startup script

[Thomas Petazzoni]

The S10udev startup script did useless things such as mounting sysfs,
mounting a tmpfs filesystem in /dev/, etc. Those things are already
done during in the default inittab.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
---
 package/udev/S10udev |   34 ----------------------------------
 1 files changed, 0 insertions(+), 34 deletions(-)

diff --git a/package/udev/S10udev b/package/udev/S10udev
index 6418f63..0d2a23a 100755
--- a/package/udev/S10udev
+++ b/package/udev/S10udev
@@ -16,12 +16,6 @@
 #	/dev/zero, /dev/null -- that's needed to boot and run this script.
 #
 
-# old kernels don't use udev
-case $(uname -r) in
-    2.6*|2.7*)	;;
-    *)		exit 0;;
-esac
-
 # Check for missing binaries
 UDEV_BIN=/sbin/udevd
 test -x $UDEV_BIN || exit 5
@@ -33,41 +27,13 @@ UDEV_CONFIG=/etc/udev/udev.conf
 test -r $UDEV_CONFIG || exit 6
 . $UDEV_CONFIG
 
-# Directory where sysfs is mounted
-SYSFS_DIR=/sys
-
 case "$1" in
     start)
-        # mount sysfs if it's not yet mounted
-        if [ ! -d $SYSFS_DIR ]; then
-	    echo "${0}: SYSFS_DIR \"$SYSFS_DIR\" not found"
-	    exit 1
-        fi
-        grep -q "^sysfs $SYSFS_DIR" /proc/mounts ||
-	mount -t sysfs /sys /sys ||
-	exit 1
-
-        # mount $udev_root as ramfs if it's not yet mounted
-        # we know 2.6 kernels always support ramfs
-        if [ ! -d $udev_root ]; then
-	    echo "${0}: udev_root \"$udev_root\" not found"
-	    exit 1
-        fi
-        grep -q "^udev $udev_root" /proc/mounts ||
-	mount -t ramfs udev $udev_root ||
-	exit 1
-
-        mkdir $udev_root/pts $udev_root/shm
         mknod -m 0666 /dev/null c 1 3
-        mknod -m 0666 /dev/zero c 1 5
-        mknod -m 0600 /dev/console c 5 1
-
-        # populate /dev (normally)
         echo -n "Populating $udev_root using udev: "
         echo -e '\000\000\000\000' > /proc/sys/kernel/hotplug
         $UDEV_BIN -d || (echo "FAIL" && exit 1)
 	$UDEVSTART_BIN || (echo "FAIL" && exit 1)
-	mount -t devpts /dev/pts /dev/pts || (echo "FAIL" && exit 1)
         echo "done"
         ;;
     stop)
-- 
1.7.1

[Buildroot] [PATCH 3/3] Allow several device tables and split in two parts our device table

[Thomas Petazzoni]

This allows to have a device table for all directories/files and
another device table for the device files themselves. Both are needed
for static /dev, but only the first one is needed when
devtmpfs/mdev/udev are used.

We take this opportunity to move the documentation of the device table
format in a common location, package/makedevs/README.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
---
 fs/Config.in                        |   20 +++-
 fs/common.mk                        |   14 ++-
 package/makedevs/README             |   35 +++++++
 target/generic/device_table.txt     |  186 ++--------------------------------
 target/generic/device_table_dev.txt |  142 ++++++++++++++++++++++++++
 5 files changed, 211 insertions(+), 186 deletions(-)
 create mode 100644 package/makedevs/README
 create mode 100644 target/generic/device_table_dev.txt

diff --git a/fs/Config.in b/fs/Config.in
index 9ac3acc..636e316 100644
--- a/fs/Config.in
+++ b/fs/Config.in
@@ -36,13 +36,21 @@ config BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_UDEV
 endchoice
 
 config BR2_ROOTFS_DEVICE_TABLE
-	string "Path to the device table"
-	depends on BR2_ROOTFS_DEVICE_CREATION_STATIC
-	default "target/generic/device_table.txt"
+	string "Path to the device tables"
+	default "target/generic/device_table.txt target/generic/device_table_dev.txt" \
+		if BR2_ROOTFS_DEVICE_CREATION_STATIC
+	default "target/generic/device_table.txt" \
+		if (BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_MDEV || \
+		    BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_UDEV || \
+		    BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_DEVTMPFS)
 	help
-	  Specify the location of a device table, that will be passed
-	  to the makedevs utility to create all the special device
-	  files in the target filesystem.
+	  Specify a space-separated list of device table locations,
+	  that will be passed to the makedevs utility to create all
+	  the special device files and assign correct owners and
+	  permissions on various files in the target filesystem.
+
+          See package/makedevs/README for details on the usage and
+          syntax of these files.
 
 choice
 	prompt "Root FS skeleton"
diff --git a/fs/common.mk b/fs/common.mk
index 92be00c..f105af2 100644
--- a/fs/common.mk
+++ b/fs/common.mk
@@ -32,7 +32,8 @@
 # macro will automatically generate a compressed filesystem image.
 
 FAKEROOT_SCRIPT = $(BUILD_DIR)/_fakeroot.fs
-ROOTFS_DEVICE_TABLE = $(call qstrip,$(BR2_ROOTFS_DEVICE_TABLE))
+FULL_DEVICE_TABLE = $(BUILD_DIR)/_device_table.txt
+ROOTFS_DEVICE_TABLES = $(call qstrip,$(BR2_ROOTFS_DEVICE_TABLE))
 
 define ROOTFS_TARGET_INTERNAL
 
@@ -42,17 +43,20 @@ $(eval ROOTFS_$(2)_DEPENDENCIES += host-fakeroot host-makedevs $(if $(BR2_TARGET
 $(BINARIES_DIR)/rootfs.$(1): $(ROOTFS_$(2)_DEPENDENCIES)
 	@$(call MESSAGE,"Generating root filesystem image rootfs.$(1)")
 	$(foreach hook,$(ROOTFS_$(2)_PRE_GEN_HOOKS),$(call $(hook))$(sep))
-	rm -f $(FAKEROOT_SCRIPT)
+	rm -f $(FAKEROOT_SCRIPT) $(FULL_DEVICE_TABLE)
 	touch $(BUILD_DIR)/.fakeroot.00000
 	cat $(BUILD_DIR)/.fakeroot* > $(FAKEROOT_SCRIPT)
 	echo "chown -R 0:0 $(TARGET_DIR)" >> $(FAKEROOT_SCRIPT)
-ifneq ($(ROOTFS_DEVICE_TABLE),)
-	echo "$(HOST_DIR)/usr/bin/makedevs -d $(ROOTFS_DEVICE_TABLE) $(TARGET_DIR)" >> $(FAKEROOT_SCRIPT)
+ifneq ($(ROOTFS_DEVICE_TABLES),)
+	for devtable in $(ROOTFS_DEVICE_TABLES) ; do \
+		cat $$$${devtable} >> $(FULL_DEVICE_TABLE) ; \
+	done
+	echo "$(HOST_DIR)/usr/bin/makedevs -d $(FULL_DEVICE_TABLE) $(TARGET_DIR)" >> $(FAKEROOT_SCRIPT)
 endif
 	echo "$(ROOTFS_$(2)_CMD)" >> $(FAKEROOT_SCRIPT)
 	chmod a+x $(FAKEROOT_SCRIPT)
 	$(HOST_DIR)/usr/bin/fakeroot -- $(FAKEROOT_SCRIPT)
-	- at rm -f $(FAKEROOT_SCRIPT)
+	- at rm -f $(FAKEROOT_SCRIPT) $(FULL_DEVICE_TABLE)
 	$(foreach hook,$(ROOTFS_$(2)_POST_GEN_HOOKS),$(call $(hook))$(sep))
 ifeq ($$(BR2_TARGET_ROOTFS_$(2)_GZIP),y)
 	gzip -9 -c $$@ > $$@.gz
diff --git a/package/makedevs/README b/package/makedevs/README
new file mode 100644
index 0000000..6c54052
--- /dev/null
+++ b/package/makedevs/README
@@ -0,0 +1,35 @@
+When building a target filesystem, it is desirable to not have to
+become root and then run 'mknod' a thousand times.  Using a device
+table you can create device nodes and directories "on the fly".
+
+You can do all sorts of interesting things with a device table file.
+For example, if you want to adjust the permissions on a particular
+file you can just add an entry like:
+
+  /sbin/foobar        f       2755    0       0       -       -       -       -       -
+
+and (assuming the file /sbin/foobar exists) it will be made setuid
+root (regardless of what its permissions are on the host filesystem.
+
+Furthermore, you can use a single table entry to create a many device
+minors.  For example, if I wanted to create /dev/hda and
+/dev/hda[0-15] I could just use the following two table entries:
+
+  /dev/hda    b       640     0       0       3       0       0       0       -
+  /dev/hda    b       640     0       0       3       1       1       1       15
+
+Device table entries take the form of:
+
+<name>    <type>      <mode>  <uid>   <gid>   <major> <minor> <start> <inc>   <count>
+
+where name is the file name,  type can be one of:
+
+      f       A regular file
+      d       Directory
+      c       Character special device file
+      b       Block special device file
+      p       Fifo (named pipe)
+
+uid is the user id for the target file, gid is the group id for the
+target file.  The rest of the entries (major, minor, etc) apply only
+to device special files.
diff --git a/target/generic/device_table.txt b/target/generic/device_table.txt
index 15132f9..12f35b2 100644
--- a/target/generic/device_table.txt
+++ b/target/generic/device_table.txt
@@ -1,44 +1,15 @@
-# When building a target filesystem, it is desirable to not have to
-# become root and then run 'mknod' a thousand times.  Using a device 
-# table you can create device nodes and directories "on the fly".
+# See package/makedevs/README for details
 #
-# This is a sample device table file for use with genext2fs.  You can
-# do all sorts of interesting things with a device table file.  For
-# example, if you want to adjust the permissions on a particular file
-# you can just add an entry like:
-#   /sbin/foobar        f       2755    0       0       -       -       -       -       -
-# and (assuming the file /sbin/foobar exists) it will be made setuid
-# root (regardless of what its permissions are on the host filesystem.
-# Furthermore, you can use a single table entry to create a many device
-# minors.  For example, if I wanted to create /dev/hda and /dev/hda[0-15]
-# I could just use the following two table entries:
-#   /dev/hda    b       640     0       0       3       0       0       0       -
-#   /dev/hda    b       640     0       0       3       1       1       1       15
-# 
-# Device table entries take the form of:
-# <name>    <type>      <mode>  <uid>   <gid>   <major> <minor> <start> <inc>   <count>
-# where name is the file name,  type can be one of: 
-#       f       A regular file
-#       d       Directory
-#       c       Character special device file
-#       b       Block special device file
-#       p       Fifo (named pipe)
-# uid is the user id for the target file, gid is the group id for the
-# target file.  The rest of the entries (major, minor, etc) apply only 
-# to device special files.
-
-# Have fun
-# -Erik Andersen <andersen@codepoet.org>
+# This device table is used to assign proper ownership and permissions
+# on various files. It doesn't create any device file, as it is used
+# in both static device configurations (where /dev/ is static) and in
+# dynamic configurations (where devtmpfs, mdev or udev are used).
 #
-
-#<name>		<type>	<mode>	<uid>	<gid>	<major>	<minor>	<start>	<inc>	<count>
-/dev		d	755	0	0	-	-	-	-	-
-/dev/pts	d	755	0	0	-	-	-	-	-
-/dev/shm	d	755	0	0	-	-	-	-	-
-/tmp		d	1777	0	0	-	-	-	-	-
-/etc		d	755	0	0	-	-	-	-	-
-/home/default	d	2755	1000	1000	-	-	-	-	-
-#<name>					<type>	<mode>	<uid>	<gid>	<major>	<minor>	<start>	<inc>	<count>
+# <name>				<type>	<mode>	<uid>	<gid>	<major>	<minor>	<start>	<inc>	<count>
+/dev					d	755	0	0	-	-	-	-	-
+/tmp					d	1777	0	0	-	-	-	-	-
+/etc					d	755	0	0	-	-	-	-	-
+/home/default				d	2755	1000	1000	-	-	-	-	-
 /bin/busybox				f	4755	0	0	-	-	-	-	-
 /etc/shadow				f	600	0	0	-	-	-	-	-
 /etc/passwd				f	644	0	0	-	-	-	-	-
@@ -48,139 +19,4 @@
 /etc/network/if-post-down.d		d	755	0	0	-	-	-	-	-
 /usr/share/udhcpc/default.script	f	755	0	0	-	-	-	-	-
 # uncomment this to allow starting x as non-root
-#/usr/X11R6/bin/Xfbdev		f	4755	0	0	-	-	-	-	-
-# Normal system devices
-/dev/mem	c	640	0	0	1	1	0	0	-
-/dev/kmem	c	640	0	0	1	2	0	0	-
-/dev/null	c	666	0	0	1	3	0	0	-
-/dev/zero	c	666	0	0	1	5	0	0	-
-/dev/random	c	666	0	0	1	8	0	0	-
-/dev/urandom	c	666	0	0	1	9	0	0	-
-/dev/ram	b	640	0	0	1	1	0	0	-
-/dev/ram	b	640	0	0	1	0	0	1	4
-/dev/loop	b	640	0	0	7	0	0	1	2
-/dev/rtc	c	640	0	0	10	135	-	-	-
-/dev/console	c	666	0	0	5	1	-	-	-
-/dev/tty	c	666	0	0	5	0	-	-	-
-/dev/tty	c	666	0	0	4	0	0	1	8
-/dev/ttyp	c	666	0	0	3	0	0	1	10
-/dev/ptyp	c       666     0       0       2       0       0       1       10
-/dev/ptmx	c	666	0	0	5	2	-	-	-
-/dev/ttyP	c	666	0	0	57	0	0	1	4
-/dev/ttyS	c	666	0	0	4	64	0	1	4
-/dev/fb		c	640	0	5	29	0	0	1	4
-#/dev/ttySA	c	666	0	0	204	5	0	1	3
-/dev/psaux	c	666	0	0	10	1	0	0	-
-#/dev/ppp	c	666	0	0	108	0	-	-	-
-/dev/ttyAM	c	666	0	0	204	16	0	1	3
-/dev/ttyCPM	c	666	0	0	204	46	0	1	4
-/dev/ttyAMA	c	666	0	0	204	64	0	1	4
-/dev/ttySAC	c	666	0	0	204	64	0	1	4
-/dev/ttyPSC	c	666	0	0	204	148	0	1	4
-/dev/ttyUL	c	666	0	0	204	187	0	1	4
-/dev/ttymxc	c	666	0	0	207	16	0	1	3
-
-# Input stuff
-/dev/input		d	755	0	0	-	-	-	-	-
-/dev/input/mice		c	640	0	0	13	63	0	0	-
-/dev/input/mouse	c	660	0	0	13	32	0	1	4
-/dev/input/event	c	660	0	0	13	64	0	1	4
-#/dev/input/js		c	660	0	0	13	0	0	1	4
-
-
-# MTD stuff
-/dev/mtd	c	640	0	0	90	0	0	2	4
-/dev/mtdblock	b	640	0	0	31	0	0	1	4
-
-#Tun/tap driver
-/dev/net	d	755	0	0	-	-	-	-	-
-/dev/net/tun	c	660	0	0	10	200	-	-	-
-
-# Audio stuff
-#/dev/audio	c	666	0	29	14	4	-	-	-
-#/dev/audio1	c	666	0	29	14	20	-	-	-
-#/dev/dsp	c	666	0	29	14	3	-	-	-
-#/dev/dsp1	c	666	0	29	14	19	-	-	-
-#/dev/sndstat	c	666	0	29	14	6	-	-	-
-
-# User-mode Linux stuff
-#/dev/ubda	b	640	0	0	98	0	0	0	-
-#/dev/ubda	b	640	0	0	98	1	1	1	15
-
-# IDE Devices
-/dev/hda	b	640	0	0	3	0	0	0	-
-/dev/hda	b	640	0	0	3	1	1	1	15
-/dev/hdb	b	640	0	0	3	64	0	0	-
-/dev/hdb	b	640	0	0	3	65	1	1	15
-#/dev/hdc	b	640	0	0	22	0	0	0	-
-#/dev/hdc	b	640	0	0	22	1	1	1	15
-#/dev/hdd	b	640	0	0	22	64	0	0	-
-#/dev/hdd	b	640	0	0	22	65	1	1	15
-#/dev/hde	b	640	0	0	33	0	0	0	-
-#/dev/hde	b	640	0	0	33	1	1	1	15
-#/dev/hdf	b	640	0	0	33	64	0	0	-
-#/dev/hdf	b	640	0	0	33	65	1	1	15
-#/dev/hdg	b	640	0	0	34	0	0	0	-
-#/dev/hdg	b	640	0	0	34	1	1	1	15
-#/dev/hdh	b	640	0	0	34	64	0	0	-
-#/dev/hdh	b	640	0	0	34	65	1	1	15
-
-# SCSI Devices
-/dev/sda	b	640	0	0	8	0	0	0	-
-/dev/sda	b	640	0	0	8	1	1	1	15
-/dev/sdb	b	640	0	0	8	16	0	0	-
-/dev/sdb	b	640	0	0	8	17	1	1	15
-#/dev/sdc	b	640	0	0	8	32	0	0	-
-#/dev/sdc	b	640	0	0	8	33	1	1	15
-#/dev/sdd	b	640	0	0	8	48	0	0	-
-#/dev/sdd	b	640	0	0	8	49	1	1	15
-#/dev/sde	b	640	0	0	8	64	0	0	-
-#/dev/sde	b	640	0	0	8	65	1	1	15
-#/dev/sdf	b	640	0	0	8	80	0	0	-
-#/dev/sdf	b	640	0	0	8	81	1	1	15
-#/dev/sdg	b	640	0	0	8	96	0	0	-
-#/dev/sdg	b	640	0	0	8	97	1	1	15
-#/dev/sdh	b	640	0	0	8	112	0	0	-
-#/dev/sdh	b	640	0	0	8	113	1	1	15
-#/dev/sg	c	640	0	0	21	0	0	1	15
-#/dev/scd	b	640	0	0	11	0	0	1	15
-#/dev/st	c	640	0	0	9	0	0	1	8
-#/dev/nst	c	640	0	0	9	128	0	1	8
-#/dev/st	c	640	0	0	9	32	1	1	4
-#/dev/st	c	640	0	0	9	64	1	1	4
-#/dev/st	c	640	0	0	9	96	1	1	4
-
-# USB block devices (ub driver)
-/dev/uba	b	640	0	0	180	0	0	0	-
-/dev/uba	b	640	0	0	180	1	1	1	6
-/dev/ubb	b	640	0	0	180	8	0	0	-
-/dev/ubb	b	640	0	0	180	65	1	1	6
-
-# Floppy disk devices
-#/dev/fd	b	640	0	0	2	0	0	1	2
-#/dev/fd0d360	b	640	0	0	2	4	0	0	-
-#/dev/fd1d360	b	640	0	0	2	5	0	0	-
-#/dev/fd0h1200	b	640	0	0	2	8	0	0	-
-#/dev/fd1h1200	b	640	0	0	2	9	0	0	-
-#/dev/fd0u1440	b	640	0	0	2	28	0	0	-
-#/dev/fd1u1440	b	640	0	0	2	29	0	0	-
-#/dev/fd0u2880	b	640	0	0	2	32	0	0	-
-#/dev/fd1u2880	b	640	0	0	2	33	0	0	-
-
-# All the proprietary cdrom devices in the world
-#/dev/aztcd	b	640	0	0	29	0	0	0	-
-#/dev/bpcd	b	640	0	0	41	0	0	0	-
-#/dev/capi20	c	640	0	0	68	0	0	1	2
-#/dev/cdu31a	b	640	0	0	15	0	0	0	-
-#/dev/cdu535	b	640	0	0	24	0	0	0	-
-#/dev/cm206cd	b	640	0	0	32	0	0	0	-
-#/dev/sjcd	b	640	0	0	18	0	0	0	-
-#/dev/sonycd	b	640	0	0	15	0	0	0	-
-#/dev/gscd	b	640	0	0	16	0	0	0	-
-#/dev/sbpcd	b	640	0	0	25	0	0	0	-
-#/dev/sbpcd	b	640	0	0	25	0	0	1	4
-#/dev/mcd	b	640	0	0	23	0	0	0	-
-#/dev/optcd	b	640	0	0	17	0	0	0	-
-
-# I2C device nodes
-/dev/i2c-	c	666	0	0	89	0	0	1	4
+#/usr/X11R6/bin/Xfbdev		     	f	4755	0	0	-	-	-	-	-
diff --git a/target/generic/device_table_dev.txt b/target/generic/device_table_dev.txt
new file mode 100644
index 0000000..0890a47
--- /dev/null
+++ b/target/generic/device_table_dev.txt
@@ -0,0 +1,142 @@
+# See package/makedevs/README for details
+#
+# This device table is used only to create device files when a static
+# device configuration is used (entries in /dev are static).
+#
+# <name>	<type>	<mode>	<uid>	<gid>	<major>	<minor>	<start>	<inc>	<count>
+
+# Normal system devices
+/dev/mem	c	640	0	0	1	1	0	0	-
+/dev/kmem	c	640	0	0	1	2	0	0	-
+/dev/null	c	666	0	0	1	3	0	0	-
+/dev/zero	c	666	0	0	1	5	0	0	-
+/dev/random	c	666	0	0	1	8	0	0	-
+/dev/urandom	c	666	0	0	1	9	0	0	-
+/dev/ram	b	640	0	0	1	1	0	0	-
+/dev/ram	b	640	0	0	1	0	0	1	4
+/dev/loop	b	640	0	0	7	0	0	1	2
+/dev/rtc	c	640	0	0	10	135	-	-	-
+/dev/console	c	666	0	0	5	1	-	-	-
+/dev/tty	c	666	0	0	5	0	-	-	-
+/dev/tty	c	666	0	0	4	0	0	1	8
+/dev/ttyp	c	666	0	0	3	0	0	1	10
+/dev/ptyp	c       666     0       0       2       0       0       1       10
+/dev/ptmx	c	666	0	0	5	2	-	-	-
+/dev/ttyP	c	666	0	0	57	0	0	1	4
+/dev/ttyS	c	666	0	0	4	64	0	1	4
+/dev/fb		c	640	0	5	29	0	0	1	4
+#/dev/ttySA	c	666	0	0	204	5	0	1	3
+/dev/psaux	c	666	0	0	10	1	0	0	-
+#/dev/ppp	c	666	0	0	108	0	-	-	-
+/dev/ttyAM	c	666	0	0	204	16	0	1	3
+/dev/ttyCPM	c	666	0	0	204	46	0	1	4
+/dev/ttyAMA	c	666	0	0	204	64	0	1	4
+/dev/ttySAC	c	666	0	0	204	64	0	1	4
+/dev/ttyPSC	c	666	0	0	204	148	0	1	4
+/dev/ttyUL	c	666	0	0	204	187	0	1	4
+/dev/ttymxc	c	666	0	0	207	16	0	1	3
+
+# Input stuff
+/dev/input		d	755	0	0	-	-	-	-	-
+/dev/input/mice		c	640	0	0	13	63	0	0	-
+/dev/input/mouse	c	660	0	0	13	32	0	1	4
+/dev/input/event	c	660	0	0	13	64	0	1	4
+#/dev/input/js		c	660	0	0	13	0	0	1	4
+
+
+# MTD stuff
+/dev/mtd	c	640	0	0	90	0	0	2	4
+/dev/mtdblock	b	640	0	0	31	0	0	1	4
+
+#Tun/tap driver
+/dev/net	d	755	0	0	-	-	-	-	-
+/dev/net/tun	c	660	0	0	10	200	-	-	-
+
+# Audio stuff
+#/dev/audio	c	666	0	29	14	4	-	-	-
+#/dev/audio1	c	666	0	29	14	20	-	-	-
+#/dev/dsp	c	666	0	29	14	3	-	-	-
+#/dev/dsp1	c	666	0	29	14	19	-	-	-
+#/dev/sndstat	c	666	0	29	14	6	-	-	-
+
+# User-mode Linux stuff
+#/dev/ubda	b	640	0	0	98	0	0	0	-
+#/dev/ubda	b	640	0	0	98	1	1	1	15
+
+# IDE Devices
+/dev/hda	b	640	0	0	3	0	0	0	-
+/dev/hda	b	640	0	0	3	1	1	1	15
+/dev/hdb	b	640	0	0	3	64	0	0	-
+/dev/hdb	b	640	0	0	3	65	1	1	15
+#/dev/hdc	b	640	0	0	22	0	0	0	-
+#/dev/hdc	b	640	0	0	22	1	1	1	15
+#/dev/hdd	b	640	0	0	22	64	0	0	-
+#/dev/hdd	b	640	0	0	22	65	1	1	15
+#/dev/hde	b	640	0	0	33	0	0	0	-
+#/dev/hde	b	640	0	0	33	1	1	1	15
+#/dev/hdf	b	640	0	0	33	64	0	0	-
+#/dev/hdf	b	640	0	0	33	65	1	1	15
+#/dev/hdg	b	640	0	0	34	0	0	0	-
+#/dev/hdg	b	640	0	0	34	1	1	1	15
+#/dev/hdh	b	640	0	0	34	64	0	0	-
+#/dev/hdh	b	640	0	0	34	65	1	1	15
+
+# SCSI Devices
+/dev/sda	b	640	0	0	8	0	0	0	-
+/dev/sda	b	640	0	0	8	1	1	1	15
+/dev/sdb	b	640	0	0	8	16	0	0	-
+/dev/sdb	b	640	0	0	8	17	1	1	15
+#/dev/sdc	b	640	0	0	8	32	0	0	-
+#/dev/sdc	b	640	0	0	8	33	1	1	15
+#/dev/sdd	b	640	0	0	8	48	0	0	-
+#/dev/sdd	b	640	0	0	8	49	1	1	15
+#/dev/sde	b	640	0	0	8	64	0	0	-
+#/dev/sde	b	640	0	0	8	65	1	1	15
+#/dev/sdf	b	640	0	0	8	80	0	0	-
+#/dev/sdf	b	640	0	0	8	81	1	1	15
+#/dev/sdg	b	640	0	0	8	96	0	0	-
+#/dev/sdg	b	640	0	0	8	97	1	1	15
+#/dev/sdh	b	640	0	0	8	112	0	0	-
+#/dev/sdh	b	640	0	0	8	113	1	1	15
+#/dev/sg	c	640	0	0	21	0	0	1	15
+#/dev/scd	b	640	0	0	11	0	0	1	15
+#/dev/st	c	640	0	0	9	0	0	1	8
+#/dev/nst	c	640	0	0	9	128	0	1	8
+#/dev/st	c	640	0	0	9	32	1	1	4
+#/dev/st	c	640	0	0	9	64	1	1	4
+#/dev/st	c	640	0	0	9	96	1	1	4
+
+# USB block devices (ub driver)
+/dev/uba	b	640	0	0	180	0	0	0	-
+/dev/uba	b	640	0	0	180	1	1	1	6
+/dev/ubb	b	640	0	0	180	8	0	0	-
+/dev/ubb	b	640	0	0	180	65	1	1	6
+
+# Floppy disk devices
+#/dev/fd	b	640	0	0	2	0	0	1	2
+#/dev/fd0d360	b	640	0	0	2	4	0	0	-
+#/dev/fd1d360	b	640	0	0	2	5	0	0	-
+#/dev/fd0h1200	b	640	0	0	2	8	0	0	-
+#/dev/fd1h1200	b	640	0	0	2	9	0	0	-
+#/dev/fd0u1440	b	640	0	0	2	28	0	0	-
+#/dev/fd1u1440	b	640	0	0	2	29	0	0	-
+#/dev/fd0u2880	b	640	0	0	2	32	0	0	-
+#/dev/fd1u2880	b	640	0	0	2	33	0	0	-
+
+# All the proprietary cdrom devices in the world
+#/dev/aztcd	b	640	0	0	29	0	0	0	-
+#/dev/bpcd	b	640	0	0	41	0	0	0	-
+#/dev/capi20	c	640	0	0	68	0	0	1	2
+#/dev/cdu31a	b	640	0	0	15	0	0	0	-
+#/dev/cdu535	b	640	0	0	24	0	0	0	-
+#/dev/cm206cd	b	640	0	0	32	0	0	0	-
+#/dev/sjcd	b	640	0	0	18	0	0	0	-
+#/dev/sonycd	b	640	0	0	15	0	0	0	-
+#/dev/gscd	b	640	0	0	16	0	0	0	-
+#/dev/sbpcd	b	640	0	0	25	0	0	0	-
+#/dev/sbpcd	b	640	0	0	25	0	0	1	4
+#/dev/mcd	b	640	0	0	23	0	0	0	-
+#/dev/optcd	b	640	0	0	17	0	0	0	-
+
+# I2C device nodes
+/dev/i2c-	c	666	0	0	89	0	0	1	4
-- 
1.7.1

[Buildroot] [PATCH 1/3] Create menu entry to select device creation method

[Yann E. MORIN]

On Saturday 02 April 2011 18:53:32 Thomas Petazzoni wrote:
> From: Yegor Yefremov <yegor_sub1@visionsystems.de>
> 
> Four methods for the creation of device files in /dev are now
> proposed:
> 
>  - static method uses device table as before
>  - devtmpfs method enables this feature in kernel
>  - mdev method adds mdev starting script to the file system
>     and selects mdev itself for installation
>  - udev method selects udev for installation
> 
> All dynamic methods are based on devtmpfs, so one doesn't need to care
> about /dev folder.
> 
> Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
> Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
> ---
>  fs/Config.in               |   33 +++++++++++++++++++++++++++------
>  linux/linux.mk             |    7 +++++++
>  package/busybox/S10mdev    |   22 ++++++++++++++++++++++
>  package/busybox/busybox.mk |   15 +++++++++++++++
>  4 files changed, 71 insertions(+), 6 deletions(-)
>  create mode 100644 package/busybox/S10mdev
> 
> diff --git a/fs/Config.in b/fs/Config.in
> index 188e815..9ac3acc 100644
> --- a/fs/Config.in
> +++ b/fs/Config.in
> @@ -15,13 +15,34 @@ config BR2_ROOTFS_POST_BUILD_SCRIPT
>  	  only argument. Make sure the exit code of that script is 0,
>  	  otherwise make will stop after calling it.
>  
> +choice
> +	prompt "/dev management"
> +	default BR2_ROOTFS_DEVICE_CREATION_STATIC
> +
> +config BR2_ROOTFS_DEVICE_CREATION_STATIC
> +	bool "Static using device table"
> +
> +config BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_DEVTMPFS
> +	bool "Dynamic using devtmpfs only"
> +
> +config BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_MDEV
> +	bool "Dynamic using mdev"
> +	select BR2_PACKAGE_BUSYBOX
> +
> +config BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_UDEV
> +	bool "Dynamic using udev"
> +	select BR2_PACKAGE_UDEV
> +
> +endchoice
> +
>  config BR2_ROOTFS_DEVICE_TABLE
> -       string "Path to the device table"
> -       default "target/generic/device_table.txt"
> -       help
> -         Specify the location of a device table, that will be passed
> -         to the makedevs utility to create all the special device
> -         files in the target filesystem.
> +	string "Path to the device table"
> +	depends on BR2_ROOTFS_DEVICE_CREATION_STATIC
> +	default "target/generic/device_table.txt"
> +	help
> +	  Specify the location of a device table, that will be passed
> +	  to the makedevs utility to create all the special device
> +	  files in the target filesystem.
>  
>  choice
>  	prompt "Root FS skeleton"
> diff --git a/linux/linux.mk b/linux/linux.mk
> index 9076fb9..873a9e0 100644
> --- a/linux/linux.mk
> +++ b/linux/linux.mk
> @@ -130,6 +130,13 @@ ifeq ($(BR2_TARGET_ROOTFS_INITRAMFS),y)
>  	$(call KCONFIG_DISABLE_OPT,CONFIG_INITRAMFS_COMPRESSION_NONE,$(@D)/.config)
>  	$(call KCONFIG_ENABLE_OPT,CONFIG_INITRAMFS_COMPRESSION_GZIP,$(@D)/.config)
>  endif
> +ifneq ($(BR2_ROOTFS_DEVICE_CREATION_STATIC),y)
                                       ^^^^^^
> +	$(call KCONFIG_ENABLE_OPT,CONFIG_DEVTMPFS,$(@D)/.config)
> +	$(call KCONFIG_ENABLE_OPT,CONFIG_DEVTMPFS_MOUNT,$(@D)/.config)
> +endif

This should be BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_DEVTMPFS, no?

> +ifeq ($(BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_MDEV),y)
> +	$(call KCONFIG_SET_OPT,CONFIG_UEVENT_HELPER_PATH,\"/sbin/mdev\",$(@D)/.config)
> +endif

As I suggest below, I'd move that into the startup script.

>  	$(TARGET_MAKE_ENV) $(MAKE) $(LINUX26_MAKE_FLAGS) -C $(@D) oldconfig
>  	$(Q)touch $@
>  
> diff --git a/package/busybox/S10mdev b/package/busybox/S10mdev
> new file mode 100644
> index 0000000..472810b
> --- /dev/null
> +++ b/package/busybox/S10mdev
> @@ -0,0 +1,22 @@
> +#!/bin/sh
> +#
> +# Start mdev....
> +#
> +
> +case "$1" in
> +  start)
> + 	echo "Starting mdev..."
> +	/sbin/mdev -s

From busybox/docs/mdev.txt:

Here's a typical code snippet from the init script:
[0] mount -t proc proc /proc
[1] mount -t sysfs sysfs /sys
[2] echo /sbin/mdev > /proc/sys/kernel/hotplug
[3] mdev -s                                                                                                  

I see that [2] is done in the kernel's .config. I find it non-obvious,
and I would move that to the script above. It makes it easier to
follow.

Also, I did not see where /dev is mounted (as a tmpfs). If / is a RO file
system, then you can't use dynamic nodes, or you need a RW file system on
/dev.

> +	;;
> +  stop)

For completeness:
    echo "/bin/true" > /proc/sys/kernel/hotplug
    killall mdev
    sleep 2  # Leave it some time to proerly quit (adjust delay)
    killall -9 mdev

> +	;;
> +  restart|reload)

        stop + start, maybe?

> +	;;
> +  *)
> +	echo $"Usage: $0 {start|stop|restart}"
> +	exit 1
> +esac
> +
> +exit $?
> +
> +
> diff --git a/package/busybox/busybox.mk b/package/busybox/busybox.mk
> index ffd6667..711d11b 100644
> --- a/package/busybox/busybox.mk
> +++ b/package/busybox/busybox.mk
> @@ -28,6 +28,19 @@ ifndef BUSYBOX_CONFIG_FILE
>  	BUSYBOX_CONFIG_FILE = $(call qstrip,$(BR2_PACKAGE_BUSYBOX_CONFIG))
>  endif
>  
> +# If mdev will be used for device creation enable it and copy S10mdev to /etc/init.d
> +ifeq ($(BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_MDEV),y)
> +define BUSYBOX_INSTALL_MDEV_SCRIPT
> +	install -m 0755 package/busybox/S10mdev $(TARGET_DIR)/etc/init.d
> +endef
> +define BUSYBOX_SET_MDEV
> +	$(call KCONFIG_ENABLE_OPT,CONFIG_MDEV,$(BUSYBOX_BUILD_CONFIG))
> +	$(call KCONFIG_ENABLE_OPT,CONFIG_FEATURE_MDEV_CONF,$(BUSYBOX_BUILD_CONFIG))
> +	$(call KCONFIG_ENABLE_OPT,CONFIG_FEATURE_MDEV_EXEC,$(BUSYBOX_BUILD_CONFIG))
> +	$(call KCONFIG_ENABLE_OPT,CONFIG_FEATURE_MDEV_LOAD_FIRMWARE,$(BUSYBOX_BUILD_CONFIG))
> +endef
> +endif
> +
>  # If we have external syslogd, force busybox to use it
>  ifeq ($(BR2_PACKAGE_SYSKLOGD),y)
>  define BUSYBOX_SET_SYSKLOGD
> @@ -122,6 +135,7 @@ define BUSYBOX_CONFIGURE_CMDS
>  	$(BUSYBOX_SET_IPV6)
>  	$(BUSYBOX_SET_RPC)
>  	$(BUSYBOX_PREFER_STATIC)
> +	$(BUSYBOX_SET_MDEV)
>  	$(BUSYBOX_NETKITBASE)
>  	$(BUSYBOX_NETKITTELNET)
>  	@yes "" | $(MAKE) ARCH=$(KERNEL_ARCH) CROSS_COMPILE="$(TARGET_CROSS)" \
> @@ -138,6 +152,7 @@ define BUSYBOX_INSTALL_TARGET_CMDS
>  		$(INSTALL) -m 0755 -D package/busybox/udhcpc.script \
>  			$(TARGET_DIR)/usr/share/udhcpc/default.script; \
>  	fi
> +	$(BUSYBOX_INSTALL_MDEV_SCRIPT)
>  endef
>  
>  define BUSYBOX_UNINSTALL_TARGET_CMDS



-- 
.-----------------.--------------------.------------------.--------------------.
|  Yann E. MORIN  | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: |
| +33 662 376 056 | Software  Designer | \ / CAMPAIGN     |  ___               |
| +33 223 225 172 `------------.-------:  X  AGAINST      |  \e/  There is no  |
| http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL    |   v   conspiracy.  |
'------------------------------^-------^------------------^--------------------'

[Buildroot] [PATCH 3/3] Allow several device tables and split in two parts our device table

[Yann E. MORIN]

Thomas, All,

On Saturday 02 April 2011 18:53:34 Thomas Petazzoni wrote:
> This allows to have a device table for all directories/files and
> another device table for the device files themselves. Both are needed
> for static /dev, but only the first one is needed when
> devtmpfs/mdev/udev are used.
> 
> We take this opportunity to move the documentation of the device table
> format in a common location, package/makedevs/README.
> 
> Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
> ---
>  fs/Config.in                        |   20 +++-
>  fs/common.mk                        |   14 ++-
>  package/makedevs/README             |   35 +++++++
>  target/generic/device_table.txt     |  186 ++--------------------------------
>  target/generic/device_table_dev.txt |  142 ++++++++++++++++++++++++++
>  5 files changed, 211 insertions(+), 186 deletions(-)
>  create mode 100644 package/makedevs/README
>  create mode 100644 target/generic/device_table_dev.txt
> 
> diff --git a/fs/Config.in b/fs/Config.in
> index 9ac3acc..636e316 100644
> --- a/fs/Config.in
> +++ b/fs/Config.in
> @@ -36,13 +36,21 @@ config BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_UDEV
>  endchoice
>  
>  config BR2_ROOTFS_DEVICE_TABLE
> -	string "Path to the device table"
> -	depends on BR2_ROOTFS_DEVICE_CREATION_STATIC
> -	default "target/generic/device_table.txt"
> +	string "Path to the device tables"
> +	default "target/generic/device_table.txt target/generic/device_table_dev.txt" \
> +		if BR2_ROOTFS_DEVICE_CREATION_STATIC

The 'device_table.txt' file name is misleading. Maybe rename to something
like: permision_table.txt

So you get device_table.txt for creating devices, and permission_table.txt
for setting permission.

Yeah, I know, it's the same tool, it's the same format, it's the historical
name. So, keep the historical name for devices, as the name implies, and
introduce the new names just for permissions.

Bonus: it avoids the huge diff below! ;-)

> +	default "target/generic/device_table.txt" \
> +		if (BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_MDEV || \
> +		    BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_UDEV || \
> +		    BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_DEVTMPFS)
>  	help
> -	  Specify the location of a device table, that will be passed
> -	  to the makedevs utility to create all the special device
> -	  files in the target filesystem.
> +	  Specify a space-separated list of device table locations,
> +	  that will be passed to the makedevs utility to create all
> +	  the special device files and assign correct owners and
> +	  permissions on various files in the target filesystem.
> +
> +          See package/makedevs/README for details on the usage and
> +          syntax of these files.
>  
>  choice
>  	prompt "Root FS skeleton"
> diff --git a/fs/common.mk b/fs/common.mk
> index 92be00c..f105af2 100644
> --- a/fs/common.mk
> +++ b/fs/common.mk
> @@ -32,7 +32,8 @@
>  # macro will automatically generate a compressed filesystem image.
>  
>  FAKEROOT_SCRIPT = $(BUILD_DIR)/_fakeroot.fs
> -ROOTFS_DEVICE_TABLE = $(call qstrip,$(BR2_ROOTFS_DEVICE_TABLE))
> +FULL_DEVICE_TABLE = $(BUILD_DIR)/_device_table.txt
> +ROOTFS_DEVICE_TABLES = $(call qstrip,$(BR2_ROOTFS_DEVICE_TABLE))
>  
>  define ROOTFS_TARGET_INTERNAL
>  
> @@ -42,17 +43,20 @@ $(eval ROOTFS_$(2)_DEPENDENCIES += host-fakeroot host-makedevs $(if $(BR2_TARGET
>  $(BINARIES_DIR)/rootfs.$(1): $(ROOTFS_$(2)_DEPENDENCIES)
>  	@$(call MESSAGE,"Generating root filesystem image rootfs.$(1)")
>  	$(foreach hook,$(ROOTFS_$(2)_PRE_GEN_HOOKS),$(call $(hook))$(sep))
> -	rm -f $(FAKEROOT_SCRIPT)
> +	rm -f $(FAKEROOT_SCRIPT) $(FULL_DEVICE_TABLE)
>  	touch $(BUILD_DIR)/.fakeroot.00000
>  	cat $(BUILD_DIR)/.fakeroot* > $(FAKEROOT_SCRIPT)
>  	echo "chown -R 0:0 $(TARGET_DIR)" >> $(FAKEROOT_SCRIPT)
> -ifneq ($(ROOTFS_DEVICE_TABLE),)
> -	echo "$(HOST_DIR)/usr/bin/makedevs -d $(ROOTFS_DEVICE_TABLE) $(TARGET_DIR)" >> $(FAKEROOT_SCRIPT)
> +ifneq ($(ROOTFS_DEVICE_TABLES),)
> +	for devtable in $(ROOTFS_DEVICE_TABLES) ; do \
> +		cat $$$${devtable} >> $(FULL_DEVICE_TABLE) ; \
> +	done
> +	echo "$(HOST_DIR)/usr/bin/makedevs -d $(FULL_DEVICE_TABLE) $(TARGET_DIR)" >> $(FAKEROOT_SCRIPT)
>  endif
>  	echo "$(ROOTFS_$(2)_CMD)" >> $(FAKEROOT_SCRIPT)
>  	chmod a+x $(FAKEROOT_SCRIPT)
>  	$(HOST_DIR)/usr/bin/fakeroot -- $(FAKEROOT_SCRIPT)
> -	- at rm -f $(FAKEROOT_SCRIPT)
> +	- at rm -f $(FAKEROOT_SCRIPT) $(FULL_DEVICE_TABLE)
>  	$(foreach hook,$(ROOTFS_$(2)_POST_GEN_HOOKS),$(call $(hook))$(sep))
>  ifeq ($$(BR2_TARGET_ROOTFS_$(2)_GZIP),y)
>  	gzip -9 -c $$@ > $$@.gz
> diff --git a/package/makedevs/README b/package/makedevs/README
> new file mode 100644
> index 0000000..6c54052
> --- /dev/null
> +++ b/package/makedevs/README
> @@ -0,0 +1,35 @@
> +When building a target filesystem, it is desirable to not have to
> +become root and then run 'mknod' a thousand times.  Using a device
> +table you can create device nodes and directories "on the fly".
> +
> +You can do all sorts of interesting things with a device table file.
> +For example, if you want to adjust the permissions on a particular
> +file you can just add an entry like:
> +
> +  /sbin/foobar        f       2755    0       0       -       -       -       -       -
> +
> +and (assuming the file /sbin/foobar exists) it will be made setuid
> +root (regardless of what its permissions are on the host filesystem.
> +
> +Furthermore, you can use a single table entry to create a many device
> +minors.  For example, if I wanted to create /dev/hda and
> +/dev/hda[0-15] I could just use the following two table entries:
> +
> +  /dev/hda    b       640     0       0       3       0       0       0       -
> +  /dev/hda    b       640     0       0       3       1       1       1       15
> +
> +Device table entries take the form of:
> +
> +<name>    <type>      <mode>  <uid>   <gid>   <major> <minor> <start> <inc>   <count>
> +
> +where name is the file name,  type can be one of:
> +
> +      f       A regular file
> +      d       Directory
> +      c       Character special device file
> +      b       Block special device file
> +      p       Fifo (named pipe)
> +
> +uid is the user id for the target file, gid is the group id for the
> +target file.  The rest of the entries (major, minor, etc) apply only
> +to device special files.
> diff --git a/target/generic/device_table.txt b/target/generic/device_table.txt
> index 15132f9..12f35b2 100644
> --- a/target/generic/device_table.txt
> +++ b/target/generic/device_table.txt
> @@ -1,44 +1,15 @@
> -# When building a target filesystem, it is desirable to not have to
> -# become root and then run 'mknod' a thousand times.  Using a device 
> -# table you can create device nodes and directories "on the fly".
> +# See package/makedevs/README for details
>  #
> -# This is a sample device table file for use with genext2fs.  You can
> -# do all sorts of interesting things with a device table file.  For
> -# example, if you want to adjust the permissions on a particular file
> -# you can just add an entry like:
> -#   /sbin/foobar        f       2755    0       0       -       -       -       -       -
> -# and (assuming the file /sbin/foobar exists) it will be made setuid
> -# root (regardless of what its permissions are on the host filesystem.
> -# Furthermore, you can use a single table entry to create a many device
> -# minors.  For example, if I wanted to create /dev/hda and /dev/hda[0-15]
> -# I could just use the following two table entries:
> -#   /dev/hda    b       640     0       0       3       0       0       0       -
> -#   /dev/hda    b       640     0       0       3       1       1       1       15
> -# 
> -# Device table entries take the form of:
> -# <name>    <type>      <mode>  <uid>   <gid>   <major> <minor> <start> <inc>   <count>
> -# where name is the file name,  type can be one of: 
> -#       f       A regular file
> -#       d       Directory
> -#       c       Character special device file
> -#       b       Block special device file
> -#       p       Fifo (named pipe)
> -# uid is the user id for the target file, gid is the group id for the
> -# target file.  The rest of the entries (major, minor, etc) apply only 
> -# to device special files.
> -
> -# Have fun
> -# -Erik Andersen <andersen@codepoet.org>
> +# This device table is used to assign proper ownership and permissions
> +# on various files. It doesn't create any device file, as it is used
> +# in both static device configurations (where /dev/ is static) and in
> +# dynamic configurations (where devtmpfs, mdev or udev are used).
>  #
> -
> -#<name>		<type>	<mode>	<uid>	<gid>	<major>	<minor>	<start>	<inc>	<count>
> -/dev		d	755	0	0	-	-	-	-	-
> -/dev/pts	d	755	0	0	-	-	-	-	-
> -/dev/shm	d	755	0	0	-	-	-	-	-
> -/tmp		d	1777	0	0	-	-	-	-	-
> -/etc		d	755	0	0	-	-	-	-	-
> -/home/default	d	2755	1000	1000	-	-	-	-	-
> -#<name>					<type>	<mode>	<uid>	<gid>	<major>	<minor>	<start>	<inc>	<count>
> +# <name>				<type>	<mode>	<uid>	<gid>	<major>	<minor>	<start>	<inc>	<count>
> +/dev					d	755	0	0	-	-	-	-	-
> +/tmp					d	1777	0	0	-	-	-	-	-
> +/etc					d	755	0	0	-	-	-	-	-
> +/home/default				d	2755	1000	1000	-	-	-	-	-
>  /bin/busybox				f	4755	0	0	-	-	-	-	-
>  /etc/shadow				f	600	0	0	-	-	-	-	-
>  /etc/passwd				f	644	0	0	-	-	-	-	-
> @@ -48,139 +19,4 @@
>  /etc/network/if-post-down.d		d	755	0	0	-	-	-	-	-
>  /usr/share/udhcpc/default.script	f	755	0	0	-	-	-	-	-
>  # uncomment this to allow starting x as non-root
> -#/usr/X11R6/bin/Xfbdev		f	4755	0	0	-	-	-	-	-
> -# Normal system devices
> -/dev/mem	c	640	0	0	1	1	0	0	-
> -/dev/kmem	c	640	0	0	1	2	0	0	-
> -/dev/null	c	666	0	0	1	3	0	0	-
> -/dev/zero	c	666	0	0	1	5	0	0	-
> -/dev/random	c	666	0	0	1	8	0	0	-
> -/dev/urandom	c	666	0	0	1	9	0	0	-
> -/dev/ram	b	640	0	0	1	1	0	0	-
> -/dev/ram	b	640	0	0	1	0	0	1	4
> -/dev/loop	b	640	0	0	7	0	0	1	2
> -/dev/rtc	c	640	0	0	10	135	-	-	-
> -/dev/console	c	666	0	0	5	1	-	-	-
> -/dev/tty	c	666	0	0	5	0	-	-	-
> -/dev/tty	c	666	0	0	4	0	0	1	8
> -/dev/ttyp	c	666	0	0	3	0	0	1	10
> -/dev/ptyp	c       666     0       0       2       0       0       1       10
> -/dev/ptmx	c	666	0	0	5	2	-	-	-
> -/dev/ttyP	c	666	0	0	57	0	0	1	4
> -/dev/ttyS	c	666	0	0	4	64	0	1	4
> -/dev/fb		c	640	0	5	29	0	0	1	4
> -#/dev/ttySA	c	666	0	0	204	5	0	1	3
> -/dev/psaux	c	666	0	0	10	1	0	0	-
> -#/dev/ppp	c	666	0	0	108	0	-	-	-
> -/dev/ttyAM	c	666	0	0	204	16	0	1	3
> -/dev/ttyCPM	c	666	0	0	204	46	0	1	4
> -/dev/ttyAMA	c	666	0	0	204	64	0	1	4
> -/dev/ttySAC	c	666	0	0	204	64	0	1	4
> -/dev/ttyPSC	c	666	0	0	204	148	0	1	4
> -/dev/ttyUL	c	666	0	0	204	187	0	1	4
> -/dev/ttymxc	c	666	0	0	207	16	0	1	3
> -
> -# Input stuff
> -/dev/input		d	755	0	0	-	-	-	-	-
> -/dev/input/mice		c	640	0	0	13	63	0	0	-
> -/dev/input/mouse	c	660	0	0	13	32	0	1	4
> -/dev/input/event	c	660	0	0	13	64	0	1	4
> -#/dev/input/js		c	660	0	0	13	0	0	1	4
> -
> -
> -# MTD stuff
> -/dev/mtd	c	640	0	0	90	0	0	2	4
> -/dev/mtdblock	b	640	0	0	31	0	0	1	4
> -
> -#Tun/tap driver
> -/dev/net	d	755	0	0	-	-	-	-	-
> -/dev/net/tun	c	660	0	0	10	200	-	-	-
> -
> -# Audio stuff
> -#/dev/audio	c	666	0	29	14	4	-	-	-
> -#/dev/audio1	c	666	0	29	14	20	-	-	-
> -#/dev/dsp	c	666	0	29	14	3	-	-	-
> -#/dev/dsp1	c	666	0	29	14	19	-	-	-
> -#/dev/sndstat	c	666	0	29	14	6	-	-	-
> -
> -# User-mode Linux stuff
> -#/dev/ubda	b	640	0	0	98	0	0	0	-
> -#/dev/ubda	b	640	0	0	98	1	1	1	15
> -
> -# IDE Devices
> -/dev/hda	b	640	0	0	3	0	0	0	-
> -/dev/hda	b	640	0	0	3	1	1	1	15
> -/dev/hdb	b	640	0	0	3	64	0	0	-
> -/dev/hdb	b	640	0	0	3	65	1	1	15
> -#/dev/hdc	b	640	0	0	22	0	0	0	-
> -#/dev/hdc	b	640	0	0	22	1	1	1	15
> -#/dev/hdd	b	640	0	0	22	64	0	0	-
> -#/dev/hdd	b	640	0	0	22	65	1	1	15
> -#/dev/hde	b	640	0	0	33	0	0	0	-
> -#/dev/hde	b	640	0	0	33	1	1	1	15
> -#/dev/hdf	b	640	0	0	33	64	0	0	-
> -#/dev/hdf	b	640	0	0	33	65	1	1	15
> -#/dev/hdg	b	640	0	0	34	0	0	0	-
> -#/dev/hdg	b	640	0	0	34	1	1	1	15
> -#/dev/hdh	b	640	0	0	34	64	0	0	-
> -#/dev/hdh	b	640	0	0	34	65	1	1	15
> -
> -# SCSI Devices
> -/dev/sda	b	640	0	0	8	0	0	0	-
> -/dev/sda	b	640	0	0	8	1	1	1	15
> -/dev/sdb	b	640	0	0	8	16	0	0	-
> -/dev/sdb	b	640	0	0	8	17	1	1	15
> -#/dev/sdc	b	640	0	0	8	32	0	0	-
> -#/dev/sdc	b	640	0	0	8	33	1	1	15
> -#/dev/sdd	b	640	0	0	8	48	0	0	-
> -#/dev/sdd	b	640	0	0	8	49	1	1	15
> -#/dev/sde	b	640	0	0	8	64	0	0	-
> -#/dev/sde	b	640	0	0	8	65	1	1	15
> -#/dev/sdf	b	640	0	0	8	80	0	0	-
> -#/dev/sdf	b	640	0	0	8	81	1	1	15
> -#/dev/sdg	b	640	0	0	8	96	0	0	-
> -#/dev/sdg	b	640	0	0	8	97	1	1	15
> -#/dev/sdh	b	640	0	0	8	112	0	0	-
> -#/dev/sdh	b	640	0	0	8	113	1	1	15
> -#/dev/sg	c	640	0	0	21	0	0	1	15
> -#/dev/scd	b	640	0	0	11	0	0	1	15
> -#/dev/st	c	640	0	0	9	0	0	1	8
> -#/dev/nst	c	640	0	0	9	128	0	1	8
> -#/dev/st	c	640	0	0	9	32	1	1	4
> -#/dev/st	c	640	0	0	9	64	1	1	4
> -#/dev/st	c	640	0	0	9	96	1	1	4
> -
> -# USB block devices (ub driver)
> -/dev/uba	b	640	0	0	180	0	0	0	-
> -/dev/uba	b	640	0	0	180	1	1	1	6
> -/dev/ubb	b	640	0	0	180	8	0	0	-
> -/dev/ubb	b	640	0	0	180	65	1	1	6
> -
> -# Floppy disk devices
> -#/dev/fd	b	640	0	0	2	0	0	1	2
> -#/dev/fd0d360	b	640	0	0	2	4	0	0	-
> -#/dev/fd1d360	b	640	0	0	2	5	0	0	-
> -#/dev/fd0h1200	b	640	0	0	2	8	0	0	-
> -#/dev/fd1h1200	b	640	0	0	2	9	0	0	-
> -#/dev/fd0u1440	b	640	0	0	2	28	0	0	-
> -#/dev/fd1u1440	b	640	0	0	2	29	0	0	-
> -#/dev/fd0u2880	b	640	0	0	2	32	0	0	-
> -#/dev/fd1u2880	b	640	0	0	2	33	0	0	-
> -
> -# All the proprietary cdrom devices in the world
> -#/dev/aztcd	b	640	0	0	29	0	0	0	-
> -#/dev/bpcd	b	640	0	0	41	0	0	0	-
> -#/dev/capi20	c	640	0	0	68	0	0	1	2
> -#/dev/cdu31a	b	640	0	0	15	0	0	0	-
> -#/dev/cdu535	b	640	0	0	24	0	0	0	-
> -#/dev/cm206cd	b	640	0	0	32	0	0	0	-
> -#/dev/sjcd	b	640	0	0	18	0	0	0	-
> -#/dev/sonycd	b	640	0	0	15	0	0	0	-
> -#/dev/gscd	b	640	0	0	16	0	0	0	-
> -#/dev/sbpcd	b	640	0	0	25	0	0	0	-
> -#/dev/sbpcd	b	640	0	0	25	0	0	1	4
> -#/dev/mcd	b	640	0	0	23	0	0	0	-
> -#/dev/optcd	b	640	0	0	17	0	0	0	-
> -
> -# I2C device nodes
> -/dev/i2c-	c	666	0	0	89	0	0	1	4
> +#/usr/X11R6/bin/Xfbdev		     	f	4755	0	0	-	-	-	-	-
> diff --git a/target/generic/device_table_dev.txt b/target/generic/device_table_dev.txt
> new file mode 100644
> index 0000000..0890a47
> --- /dev/null
> +++ b/target/generic/device_table_dev.txt
> @@ -0,0 +1,142 @@
> +# See package/makedevs/README for details
> +#
> +# This device table is used only to create device files when a static
> +# device configuration is used (entries in /dev are static).
> +#
> +# <name>	<type>	<mode>	<uid>	<gid>	<major>	<minor>	<start>	<inc>	<count>
> +
> +# Normal system devices
> +/dev/mem	c	640	0	0	1	1	0	0	-
> +/dev/kmem	c	640	0	0	1	2	0	0	-
> +/dev/null	c	666	0	0	1	3	0	0	-
> +/dev/zero	c	666	0	0	1	5	0	0	-
> +/dev/random	c	666	0	0	1	8	0	0	-
> +/dev/urandom	c	666	0	0	1	9	0	0	-
> +/dev/ram	b	640	0	0	1	1	0	0	-
> +/dev/ram	b	640	0	0	1	0	0	1	4
> +/dev/loop	b	640	0	0	7	0	0	1	2
> +/dev/rtc	c	640	0	0	10	135	-	-	-
> +/dev/console	c	666	0	0	5	1	-	-	-
> +/dev/tty	c	666	0	0	5	0	-	-	-
> +/dev/tty	c	666	0	0	4	0	0	1	8
> +/dev/ttyp	c	666	0	0	3	0	0	1	10
> +/dev/ptyp	c       666     0       0       2       0       0       1       10
> +/dev/ptmx	c	666	0	0	5	2	-	-	-
> +/dev/ttyP	c	666	0	0	57	0	0	1	4
> +/dev/ttyS	c	666	0	0	4	64	0	1	4
> +/dev/fb		c	640	0	5	29	0	0	1	4
> +#/dev/ttySA	c	666	0	0	204	5	0	1	3
> +/dev/psaux	c	666	0	0	10	1	0	0	-
> +#/dev/ppp	c	666	0	0	108	0	-	-	-
> +/dev/ttyAM	c	666	0	0	204	16	0	1	3
> +/dev/ttyCPM	c	666	0	0	204	46	0	1	4
> +/dev/ttyAMA	c	666	0	0	204	64	0	1	4
> +/dev/ttySAC	c	666	0	0	204	64	0	1	4
> +/dev/ttyPSC	c	666	0	0	204	148	0	1	4
> +/dev/ttyUL	c	666	0	0	204	187	0	1	4
> +/dev/ttymxc	c	666	0	0	207	16	0	1	3
> +
> +# Input stuff
> +/dev/input		d	755	0	0	-	-	-	-	-
> +/dev/input/mice		c	640	0	0	13	63	0	0	-
> +/dev/input/mouse	c	660	0	0	13	32	0	1	4
> +/dev/input/event	c	660	0	0	13	64	0	1	4
> +#/dev/input/js		c	660	0	0	13	0	0	1	4
> +
> +
> +# MTD stuff
> +/dev/mtd	c	640	0	0	90	0	0	2	4
> +/dev/mtdblock	b	640	0	0	31	0	0	1	4
> +
> +#Tun/tap driver
> +/dev/net	d	755	0	0	-	-	-	-	-
> +/dev/net/tun	c	660	0	0	10	200	-	-	-
> +
> +# Audio stuff
> +#/dev/audio	c	666	0	29	14	4	-	-	-
> +#/dev/audio1	c	666	0	29	14	20	-	-	-
> +#/dev/dsp	c	666	0	29	14	3	-	-	-
> +#/dev/dsp1	c	666	0	29	14	19	-	-	-
> +#/dev/sndstat	c	666	0	29	14	6	-	-	-
> +
> +# User-mode Linux stuff
> +#/dev/ubda	b	640	0	0	98	0	0	0	-
> +#/dev/ubda	b	640	0	0	98	1	1	1	15
> +
> +# IDE Devices
> +/dev/hda	b	640	0	0	3	0	0	0	-
> +/dev/hda	b	640	0	0	3	1	1	1	15
> +/dev/hdb	b	640	0	0	3	64	0	0	-
> +/dev/hdb	b	640	0	0	3	65	1	1	15
> +#/dev/hdc	b	640	0	0	22	0	0	0	-
> +#/dev/hdc	b	640	0	0	22	1	1	1	15
> +#/dev/hdd	b	640	0	0	22	64	0	0	-
> +#/dev/hdd	b	640	0	0	22	65	1	1	15
> +#/dev/hde	b	640	0	0	33	0	0	0	-
> +#/dev/hde	b	640	0	0	33	1	1	1	15
> +#/dev/hdf	b	640	0	0	33	64	0	0	-
> +#/dev/hdf	b	640	0	0	33	65	1	1	15
> +#/dev/hdg	b	640	0	0	34	0	0	0	-
> +#/dev/hdg	b	640	0	0	34	1	1	1	15
> +#/dev/hdh	b	640	0	0	34	64	0	0	-
> +#/dev/hdh	b	640	0	0	34	65	1	1	15
> +
> +# SCSI Devices
> +/dev/sda	b	640	0	0	8	0	0	0	-
> +/dev/sda	b	640	0	0	8	1	1	1	15
> +/dev/sdb	b	640	0	0	8	16	0	0	-
> +/dev/sdb	b	640	0	0	8	17	1	1	15
> +#/dev/sdc	b	640	0	0	8	32	0	0	-
> +#/dev/sdc	b	640	0	0	8	33	1	1	15
> +#/dev/sdd	b	640	0	0	8	48	0	0	-
> +#/dev/sdd	b	640	0	0	8	49	1	1	15
> +#/dev/sde	b	640	0	0	8	64	0	0	-
> +#/dev/sde	b	640	0	0	8	65	1	1	15
> +#/dev/sdf	b	640	0	0	8	80	0	0	-
> +#/dev/sdf	b	640	0	0	8	81	1	1	15
> +#/dev/sdg	b	640	0	0	8	96	0	0	-
> +#/dev/sdg	b	640	0	0	8	97	1	1	15
> +#/dev/sdh	b	640	0	0	8	112	0	0	-
> +#/dev/sdh	b	640	0	0	8	113	1	1	15
> +#/dev/sg	c	640	0	0	21	0	0	1	15
> +#/dev/scd	b	640	0	0	11	0	0	1	15
> +#/dev/st	c	640	0	0	9	0	0	1	8
> +#/dev/nst	c	640	0	0	9	128	0	1	8
> +#/dev/st	c	640	0	0	9	32	1	1	4
> +#/dev/st	c	640	0	0	9	64	1	1	4
> +#/dev/st	c	640	0	0	9	96	1	1	4
> +
> +# USB block devices (ub driver)
> +/dev/uba	b	640	0	0	180	0	0	0	-
> +/dev/uba	b	640	0	0	180	1	1	1	6
> +/dev/ubb	b	640	0	0	180	8	0	0	-
> +/dev/ubb	b	640	0	0	180	65	1	1	6
> +
> +# Floppy disk devices
> +#/dev/fd	b	640	0	0	2	0	0	1	2
> +#/dev/fd0d360	b	640	0	0	2	4	0	0	-
> +#/dev/fd1d360	b	640	0	0	2	5	0	0	-
> +#/dev/fd0h1200	b	640	0	0	2	8	0	0	-
> +#/dev/fd1h1200	b	640	0	0	2	9	0	0	-
> +#/dev/fd0u1440	b	640	0	0	2	28	0	0	-
> +#/dev/fd1u1440	b	640	0	0	2	29	0	0	-
> +#/dev/fd0u2880	b	640	0	0	2	32	0	0	-
> +#/dev/fd1u2880	b	640	0	0	2	33	0	0	-
> +
> +# All the proprietary cdrom devices in the world
> +#/dev/aztcd	b	640	0	0	29	0	0	0	-
> +#/dev/bpcd	b	640	0	0	41	0	0	0	-
> +#/dev/capi20	c	640	0	0	68	0	0	1	2
> +#/dev/cdu31a	b	640	0	0	15	0	0	0	-
> +#/dev/cdu535	b	640	0	0	24	0	0	0	-
> +#/dev/cm206cd	b	640	0	0	32	0	0	0	-
> +#/dev/sjcd	b	640	0	0	18	0	0	0	-
> +#/dev/sonycd	b	640	0	0	15	0	0	0	-
> +#/dev/gscd	b	640	0	0	16	0	0	0	-
> +#/dev/sbpcd	b	640	0	0	25	0	0	0	-
> +#/dev/sbpcd	b	640	0	0	25	0	0	1	4
> +#/dev/mcd	b	640	0	0	23	0	0	0	-
> +#/dev/optcd	b	640	0	0	17	0	0	0	-
> +
> +# I2C device nodes
> +/dev/i2c-	c	666	0	0	89	0	0	1	4



-- 
.-----------------.--------------------.------------------.--------------------.
|  Yann E. MORIN  | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: |
| +33 662 376 056 | Software  Designer | \ / CAMPAIGN     |  ___               |
| +33 223 225 172 `------------.-------:  X  AGAINST      |  \e/  There is no  |
| http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL    |   v   conspiracy.  |
'------------------------------^-------^------------------^--------------------'

[Buildroot] [PATCH 1/3] Create menu entry to select device creation method

[Thomas Petazzoni]

Hello,

On Sat, 2 Apr 2011 19:21:50 +0200
"Yann E. MORIN" <yann.morin.1998@anciens.enib.fr> wrote:

> > +ifneq ($(BR2_ROOTFS_DEVICE_CREATION_STATIC),y)
>                                        ^^^^^^
> > +	$(call KCONFIG_ENABLE_OPT,CONFIG_DEVTMPFS,$(@D)/.config)
> > +	$(call KCONFIG_ENABLE_OPT,CONFIG_DEVTMPFS_MOUNT,$(@D)/.config)
> > +endif
> 
> This should be BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_DEVTMPFS, no?

This is what I originally implemented, but I was told that using
devtmpfs was easier even in the udev/mdev cases for the early boot part
(i.e before udev/mdev are working).

See
http://lists.busybox.net/pipermail/buildroot/2010-December/039886.html
for Peter's comment on the matter.

> > +ifeq ($(BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_MDEV),y)
> > +	$(call KCONFIG_SET_OPT,CONFIG_UEVENT_HELPER_PATH,\"/sbin/mdev\",$(@D)/.config)
> > +endif
> 
> As I suggest below, I'd move that into the startup script.

Hmm, why not.

> >  	$(TARGET_MAKE_ENV) $(MAKE) $(LINUX26_MAKE_FLAGS) -C $(@D) oldconfig
> >  	$(Q)touch $@
> >  
> > diff --git a/package/busybox/S10mdev b/package/busybox/S10mdev
> > new file mode 100644
> > index 0000000..472810b
> > --- /dev/null
> > +++ b/package/busybox/S10mdev
> > @@ -0,0 +1,22 @@
> > +#!/bin/sh
> > +#
> > +# Start mdev....
> > +#
> > +
> > +case "$1" in
> > +  start)
> > + 	echo "Starting mdev..."
> > +	/sbin/mdev -s
> 
> >From busybox/docs/mdev.txt:
> 
> Here's a typical code snippet from the init script:
> [0] mount -t proc proc /proc
> [1] mount -t sysfs sysfs /sys
> [2] echo /sbin/mdev > /proc/sys/kernel/hotplug
> [3] mdev -s                                                                                                  
> 
> I see that [2] is done in the kernel's .config. I find it non-obvious,
> and I would move that to the script above. It makes it easier to
> follow.

I guess that's a matter of taste. I have no strong opinion here.

> Also, I did not see where /dev is mounted (as a tmpfs). If / is a RO file
> system, then you can't use dynamic nodes, or you need a RW file system on
> /dev.

/dev is a devtmpfs filesystem, thanks to the kernel options that you
highlighted above, and it is mounted automatically by the kernel thanks
to the CONFIG_DEVTMPFS_MOUNT option.

> > +	;;
> > +  stop)
> 
> For completeness:
>     echo "/bin/true" > /proc/sys/kernel/hotplug
>     killall mdev
>     sleep 2  # Leave it some time to proerly quit (adjust delay)
>     killall -9 mdev

mdev is not a daemon (contrary to udev), so there's no point in killing
it. It's a utility that the kernel runs where there are events to
handle.

So I don't think there's a lot of point in having the stop), restart)
and reload) commands for mdev.

Regards,

Thomas
-- 
Thomas Petazzoni, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com

[Buildroot] [PATCH 1/3] Create menu entry to select device creation method

[Yann E. MORIN]

Thomas, All,

On Sunday 03 April 2011 12:18:29 Thomas Petazzoni wrote:
> On Sat, 2 Apr 2011 19:21:50 +0200
> "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr> wrote:
> 
> > > +ifneq ($(BR2_ROOTFS_DEVICE_CREATION_STATIC),y)
> >                                        ^^^^^^

Oh, that's an 'ifneq', not an 'ifeq'. Sorry for the noise...

> > > +	$(call KCONFIG_ENABLE_OPT,CONFIG_DEVTMPFS,$(@D)/.config)
> > > +	$(call KCONFIG_ENABLE_OPT,CONFIG_DEVTMPFS_MOUNT,$(@D)/.config)
> > > +endif
> > 
> > This should be BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_DEVTMPFS, no?
> 
> This is what I originally implemented, but I was told that using
> devtmpfs was easier even in the udev/mdev cases for the early boot part
> (i.e before udev/mdev are working).

So, unless I am totally mistaken, if one chooses devtmpfs with
BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_DEVTMPFS, then devtmpfs is not forced
in the kernel's .config.

So even if the user asks for a static /dev, he nonetheless gets a devtmpfs.
So what's the point of having both options in BR?

The only difference is that, when _STATIC is selected, the user is offered
a choice to specify a device_table, and not when _DEVTMPFS is selected.

What I really find confusing is the config prompts do not actually match
the behavior. If I select 'static', I expect to get static, not dynamic
(even if only the kernel is involved).

> > > +case "$1" in
> > > +  start)
> > > + 	echo "Starting mdev..."
> > > +	/sbin/mdev -s
> > 
> > >From busybox/docs/mdev.txt:
> > 
> > Here's a typical code snippet from the init script:
> > [0] mount -t proc proc /proc
> > [1] mount -t sysfs sysfs /sys
> > [2] echo /sbin/mdev > /proc/sys/kernel/hotplug
> > [3] mdev -s                                                                                                  
> > 
> > I see that [2] is done in the kernel's .config. I find it non-obvious,
> > and I would move that to the script above. It makes it easier to
> > follow.
> 
> I guess that's a matter of taste. I have no strong opinion here.

At least, add a comment (in S10mdev, or in the config help) stating
where the setup is done. I have no strong opinion either, it just took
me a while to understand what was going on. And I find it more explicit
to get related stuff grouped together when possible.

> > Also, I did not see where /dev is mounted (as a tmpfs). If / is a RO file
> > system, then you can't use dynamic nodes, or you need a RW file system on
> > /dev.
> 
> /dev is a devtmpfs filesystem, thanks to the kernel options that you
> highlighted above, and it is mounted automatically by the kernel thanks
> to the CONFIG_DEVTMPFS_MOUNT option.

Right. I missed the ifneq, above...

> > > +	;;
> > > +  stop)
> > 
> > For completeness:
> >     echo "/bin/true" > /proc/sys/kernel/hotplug
> >     killall mdev
> >     sleep 2  # Leave it some time to proerly quit (adjust delay)
> >     killall -9 mdev
> 
> mdev is not a daemon (contrary to udev), so there's no point in killing
> it. It's a utility that the kernel runs where there are events to
> handle.

Yeah, right. 'mdev -s' is here to handle coldplug events. My bad.

> So I don't think there's a lot of point in having the stop), restart)
> and reload) commands for mdev.

Forget my silly comment. So:

Reviewed by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

Regards,
Yann E. MORIN.

-- 
.-----------------.--------------------.------------------.--------------------.
|  Yann E. MORIN  | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: |
| +33 662 376 056 | Software  Designer | \ / CAMPAIGN     |  ___               |
| +33 223 225 172 `------------.-------:  X  AGAINST      |  \e/  There is no  |
| http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL    |   v   conspiracy.  |
'------------------------------^-------^------------------^--------------------'

[Buildroot] [PATCH 1/3] Create menu entry to select device creation method

[Yann E. MORIN]

Thomas, All,

On Sunday 03 April 2011 20:05:00 Yann E. MORIN wrote:
> So, unless I am totally mistaken, if one chooses devtmpfs with
> BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_DEVTMPFS, then devtmpfs is not forced
> in the kernel's .config.
> 
> So even if the user asks for a static /dev, he nonetheless gets a devtmpfs.
> So what's the point of having both options in BR?
> 
> The only difference is that, when _STATIC is selected, the user is offered
> a choice to specify a device_table, and not when _DEVTMPFS is selected.
> 
> What I really find confusing is the config prompts do not actually match
> the behavior. If I select 'static', I expect to get static, not dynamic
> (even if only the kernel is involved).

And forget the above, I forgot to delete it when I saw the 'ifneq' stuff.

Regards,
Yann E. MORIN.

-- 
.-----------------.--------------------.------------------.--------------------.
|  Yann E. MORIN  | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: |
| +33 662 376 056 | Software  Designer | \ / CAMPAIGN     |  ___               |
| +33 223 225 172 `------------.-------:  X  AGAINST      |  \e/  There is no  |
| http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL    |   v   conspiracy.  |
'------------------------------^-------^------------------^--------------------'

[Buildroot] [PATCH 3/3] Allow several device tables and split in two parts our device table

[Thomas De Schampheleire]

On Sat, Apr 2, 2011 at 6:53 PM, Thomas Petazzoni
<thomas.petazzoni@free-electrons.com> wrote:
> This allows to have a device table for all directories/files and
> another device table for the device files themselves. Both are needed
> for static /dev, but only the first one is needed when
> devtmpfs/mdev/udev are used.
>
> We take this opportunity to move the documentation of the device table
> format in a common location, package/makedevs/README.
>
> Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
> ---
> ?fs/Config.in ? ? ? ? ? ? ? ? ? ? ? ?| ? 20 +++-
> ?fs/common.mk ? ? ? ? ? ? ? ? ? ? ? ?| ? 14 ++-
> ?package/makedevs/README ? ? ? ? ? ? | ? 35 +++++++

The source file makedevs.c also contains some documentation, with more
examples. I think it would be best to keep just one: either the README
file (expanded with the documentation in the sources), or the source
documentation.

Best regards,
Thomas

> ?target/generic/device_table.txt ? ? | ?186 ++--------------------------------
> ?target/generic/device_table_dev.txt | ?142 ++++++++++++++++++++++++++
> ?5 files changed, 211 insertions(+), 186 deletions(-)
> ?create mode 100644 package/makedevs/README
> ?create mode 100644 target/generic/device_table_dev.txt
>