From a4798eb42a261ff39d991b198a09b840c11010d5 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Mon, 20 Jan 2020 12:23:12 +0900 Subject: Documentation: bootconfig: Fix typos in bootconfig documentation Fix typos in bootconfig.rst according to Randy's suggestions. Link: http://lkml.kernel.org/r/157949059219.25888.16939971423610233631.stgit@devnote2 Suggested-by: Randy Dunlap Acked-by: Randy Dunlap Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) --- Documentation/admin-guide/bootconfig.rst | 32 +++++++++++++++++--------------- 1 file changed, 17 insertions(+), 15 deletions(-) (limited to 'Documentation/admin-guide') diff --git a/Documentation/admin-guide/bootconfig.rst b/Documentation/admin-guide/bootconfig.rst index c8f7cd4cf44e..4d617693c0c8 100644 --- a/Documentation/admin-guide/bootconfig.rst +++ b/Documentation/admin-guide/bootconfig.rst @@ -11,20 +11,22 @@ Boot Configuration Overview ======== -The boot configuration is expanding current kernel cmdline to support -additional key-value data when boot the kernel in an efficient way. -This allows adoministrators to pass a structured-Key config file. +The boot configuration expands the current kernel command line to support +additional key-value data when booting the kernel in an efficient way. +This allows administrators to pass a structured-Key config file. Config File Syntax ================== The boot config syntax is a simple structured key-value. Each key consists -of dot-connected-words, and key and value are connected by "=". The value +of dot-connected-words, and key and value are connected by ``=``. The value has to be terminated by semi-colon (``;``) or newline (``\n``). For array value, array entries are separated by comma (``,``). :: KEY[.WORD[...]] = VALUE[, VALUE2[...]][;] +Unlike the kernel command line syntax, spaces are OK around the comma and ``=``. + Each key word must contain only alphabets, numbers, dash (``-``) or underscore (``_``). And each value only contains printable characters or spaces except for delimiters such as semi-colon (``;``), new-line (``\n``), comma (``,``), @@ -35,7 +37,7 @@ quotes (``"VALUE"``) or single-quotes (``'VALUE'``) to quote it. Note that you can not escape these quotes. There can be a key which doesn't have value or has an empty value. Those keys -are used for checking the key exists or not (like a boolean). +are used for checking if the key exists or not (like a boolean). Key-Value Syntax ---------------- @@ -63,7 +65,7 @@ at boot time. So you can append similar trees or key-values. Comments -------- -The config syntax accepts shell-script style comments. The comments start +The config syntax accepts shell-script style comments. The comments starting with hash ("#") until newline ("\n") will be ignored. :: @@ -108,7 +110,7 @@ update the boot loader and the kernel image itself. To do this operation, Linux kernel provides "bootconfig" command under tools/bootconfig, which allows admin to apply or delete the config file -to/from initrd image. You can build it by follwoing command:: +to/from initrd image. You can build it by the following command:: # make -C tools/bootconfig @@ -122,7 +124,7 @@ To remove the config from the image, you can use -d option as below:: # tools/bootconfig/bootconfig -d /boot/initrd.img-X.Y.Z -C onfig File Limitation +Config File Limitation ====================== Currently the maximum config size size is 32KB and the total key-words (not @@ -145,10 +147,10 @@ User can query or loop on key-value pairs, also it is possible to find a root (prefix) key node and find key-values under that node. If you have a key string, you can query the value directly with the key -using xbc_find_value(). If you want to know what keys exist in the SKC -tree, you can use xbc_for_each_key_value() to iterate key-value pairs. +using xbc_find_value(). If you want to know what keys exist in the boot +config, you can use xbc_for_each_key_value() to iterate key-value pairs. Note that you need to use xbc_array_for_each_value() for accessing -each arraies value, e.g.:: +each array's value, e.g.:: vnode = NULL; xbc_find_value("key.word", &vnode); @@ -157,8 +159,8 @@ each arraies value, e.g.:: printk("%s ", value); } -If you want to focus on keys which has a prefix string, you can use -xbc_find_node() to find a node which prefix key words, and iterate +If you want to focus on keys which have a prefix string, you can use +xbc_find_node() to find a node by the prefix string, and iterate keys under the prefix node with xbc_node_for_each_key_value(). But the most typical usage is to get the named value under prefix @@ -174,8 +176,8 @@ or get the named array under prefix as below:: This accesses a value of "key.prefix.option" and an array of "key.prefix.array-option". -Locking is not needed, since after initialized, the config becomes readonly. -All data and keys must be copied if you need to modify it. +Locking is not needed, since after initialization, the config becomes +read-only. All data and keys must be copied if you need to modify it. Functions and structures -- cgit v1.2.3-59-g8ed1b