Commit Graph

16 Commits

Author SHA1 Message Date
Masami Hiramatsu e5efaeb8a8 bootconfig: Support mixing a value and subkeys under a key
Support mixing a value and subkeys under a key. Since kernel cmdline
options will support "aaa.bbb=value1 aaa.bbb.ccc=value2", it is
better that the bootconfig supports such configuration too.

Note that this does not change syntax itself but just accepts
mixed value and subkeys e.g.

key = value1
key.subkey = value2

But this is not accepted;

key {
 value1
 subkey = value2
}

That will make value1 as a subkey.

Also, the order of the value node under a key is fixed. If there
are a value and subkeys, the value is always the first child node
of the key. Thus if user specifies subkeys first, e.g.

key.subkey = value1
key = value2

In the program (and /proc/bootconfig), it will be shown as below

key = value2
key.subkey = value1

Link: https://lkml.kernel.org/r/162262194685.264090.7738574774030567419.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-06-10 13:41:26 -04:00
Masami Hiramatsu ca24306d83 bootconfig: Change array value to use child node
It is not possible to put an array value with subkeys under
a key node, because both of subkeys and the array elements
are using "next" field of the xbc_node.

Thus this changes the array values to use "child" field in
the array case. The reason why split this change is to
test it easily.

Link: https://lkml.kernel.org/r/162262193838.264090.16044473274501498656.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-06-10 13:38:25 -04:00
Nick Desaulniers 4c1ca831ad Revert "lib: Revert use of fallthrough pseudo-keyword in lib/"
This reverts commit 6a9dc5fd61 ("lib: Revert use of fallthrough
pseudo-keyword in lib/")

Now that we can build arch/powerpc/boot/ free of -Wimplicit-fallthrough,
re-enable these fixes for lib/.

Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://github.com/ClangBuiltLinux/linux/issues/236
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-11-18 14:15:17 -06:00
Masami Hiramatsu c7af4ecdff lib/bootconfig: Fix to remove tailing spaces after value
Fix to remove tailing spaces after value. If there is a space
after value, the bootconfig failed to remove it because it
applies strim() before replacing the delimiter with null.

For example,

foo = var    # comment

was parsed as below.

foo="var    "

but user will expect

foo="var"

This fixes it by applying strim() after removing the delimiter.

Link: https://lkml.kernel.org/r/160068149134.1088739.8868306567670058853.stgit@devnote2

Fixes: 76db5a27a8 ("bootconfig: Add Extra Boot Config support")
Cc: Ingo Molnar <mingo@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-21 21:50:09 -04:00
Masami Hiramatsu ead1e19ad9 lib/bootconfig: Fix a bug of breaking existing tree nodes
Fix a bug of breaking existing tree nodes by parsing the second
and subsequent braces. Since the bootconfig parser uses the
node.next field as a flag of current parent node, but this will
break the existing tree if the same key node is specified again
in the bootconfig.

For example, the following bootconfig should be foo.buz and bar.

foo
bar
foo { buz }

However, when parsing the brace "{", it breaks foo->bar link
by marking open-brace node. So the bootconfig unlinks bar
from the bootconfig internal tree.

This introduces a stack outside of the tree and record the
last open-brace on the stack instead of using node.next field.

Link: https://lkml.kernel.org/r/160068148267.1088739.8264704338030168660.stgit@devnote2

Fixes: 76db5a27a8 ("bootconfig: Add Extra Boot Config support")
Cc: Ingo Molnar <mingo@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-21 21:45:52 -04:00
Gustavo A. R. Silva 6a9dc5fd61 lib: Revert use of fallthrough pseudo-keyword in lib/
The following build error for powerpc64 was reported by Nathan Chancellor:

  "$ scripts/config --file arch/powerpc/configs/powernv_defconfig -e KERNEL_XZ

   $ make -skj"$(nproc)" ARCH=powerpc CROSS_COMPILE=powerpc64le-linux- distclean powernv_defconfig zImage
   ...
   In file included from arch/powerpc/boot/../../../lib/decompress_unxz.c:234,
                    from arch/powerpc/boot/decompress.c:38:
   arch/powerpc/boot/../../../lib/xz/xz_dec_stream.c: In function 'dec_main':
   arch/powerpc/boot/../../../lib/xz/xz_dec_stream.c:586:4: error: 'fallthrough' undeclared (first use in this function)
     586 |    fallthrough;
         |    ^~~~~~~~~~~

   This will end up affecting distribution configurations such as Debian
   and OpenSUSE according to my testing. I am not sure what the solution
   is, the PowerPC wrapper does not set -D__KERNEL__ so I am not sure
   that compiler_attributes.h can be safely included."

In order to avoid these sort of problems, it seems that the best
solution is to use /* fall through */ comments instead of the
fallthrough pseudo-keyword macro in lib/, for now.

Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Fixes: df561f6688 ("treewide: Use fallthrough pseudo-keyword")
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-and-tested-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-24 14:17:44 -07:00
Gustavo A. R. Silva df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Masami Hiramatsu a2de2f86ae lib/bootconfig: Add override operator support
Add the value override operator (":=") support to the bootconfig.

This value override operator will be useful for the bootloaders
which will only update the existing bootconfig according to the
bootloader boot options.

Without this override operator, the bootloader needs to parse
the existing bootconfig and update it. However, with this
assignment, it can just append the updated (partial) bootconfig
text at the tail of existing one without parsing it.
(Of course, it must update the size, checksum and magic,
 but that will be done easily)

Link: https://lkml.kernel.org/r/159482882954.126704.16209517125614438640.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-08-03 16:22:28 -04:00
Masami Hiramatsu 89b74cac78 tools/bootconfig: Show line and column in parse error
Show line and column when we got a parse error in bootconfig tool.
Current lib/bootconfig shows the parse error with byte offset, but
that is not human readable.
This makes xbc_init() not showing error message itself but able to
pass the error message and position to caller, so that the caller
can decode it and show the error message with line number and columns.

With this patch, bootconfig tool shows an error with line:column as
below.

  $ cat samples/bad-dotword.bconf
  # do not start keyword with .
  key {
    .word = 1
  }
  $ ./bootconfig -a samples/bad-dotword.bconf initrd
  Parse Error: Invalid keyword at 3:3

Link: http://lkml.kernel.org/r/158323469002.10560.4023923847704522760.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-03-03 17:38:42 -05:00
Masami Hiramatsu 5f811c57c9 bootconfig: Add append value operator support
Add append value operator "+=" support to bootconfig syntax.
With this operator, user can add new value to the key as
an entry of array instead of overwriting.
For example,

  foo = bar
  ...
  foo += baz

Then the key "foo" has "bar" and "baz" values as an array.

Link: http://lkml.kernel.org/r/158227283195.12842.8310503105963275584.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-21 09:59:39 -05:00
Masami Hiramatsu 4e4694d872 bootconfig: Prohibit re-defining value on same key
Currently, bootconfig adds a new value on the existing key to the tail of an
array. But this looks a bit confusing because an admin can easily rewrite
the original value in the same config file.

This rejects the following value re-definition.

  key = value1
  ...
  key = value2

You should rewrite value1 to value2 in this case.

Link: http://lkml.kernel.org/r/158227282199.12842.10110929876059658601.stgit@devnote2

Suggested-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
[ Fixed spelling of arraies to arrays ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-21 09:59:19 -05:00
Masami Hiramatsu a24d286f36 bootconfig: Reject subkey and value on same parent key
Reject if a value node is mixed with subkey node on same
parent key node.

A value node can not co-exist with subkey node under some key
node, e.g.

key = value
key.subkey = another-value

This is not be allowed because bootconfig API is not designed
to handle such case.

Link: http://lkml.kernel.org/r/158220115232.26565.7792340045009731803.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-20 17:54:09 -05:00
Masami Hiramatsu a91e4f12ff bootconfig: Allocate xbc_nodes array dynamically
To reduce the large static array from kernel data, allocate
xbc_nodes array dynamically only if the kernel loads a
bootconfig.

Note that this also add dummy memblock.h for user-spacae
bootconfig tool.

Link: http://lkml.kernel.org/r/158108569699.3187.6512834527603883707.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-10 17:19:39 -05:00
Masami Hiramatsu 0f0d0a77cc tools/bootconfig: Show the number of bootconfig nodes
Show the number of bootconfig nodes when applying new bootconfig to
initrd.

Since there are limitations of bootconfig not only in its filesize,
but also the number of nodes, the number should be shown when applying
so that user can get the feeling of scale of current bootconfig.

Link: http://lkml.kernel.org/r/158091061337.27924.10886706631693823982.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-05 17:17:05 -05:00
Masami Hiramatsu 597c0e3b45 bootconfig: Add more parse error messages
Add more error messages for following cases.
 - Exceeding max number of nodes
 - Config tree data is empty (e.g. comment only)
 - Config data is empty or exceeding max size
 - bootconfig is already initialized

Link: http://lkml.kernel.org/r/158091060401.27924.9024818742827122764.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-05 17:17:05 -05:00
Masami Hiramatsu 76db5a27a8 bootconfig: Add Extra Boot Config support
Extra Boot Config (XBC) allows admin to pass a tree-structured
boot configuration file when boot up the kernel. This extends
the kernel command line in an efficient way.

Boot config will contain some key-value commands, e.g.

key.word = value1
another.key.word = value2

It can fold same keys with braces, also you can write array
data. For example,

key {
   word1 {
      setting1 = data
      setting2
   }
   word2.array = "val1", "val2"
}

User can access these key-value pair and tree structure via
SKC APIs.

Link: http://lkml.kernel.org/r/157867221257.17873.1775090991929862549.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-13 13:19:38 -05:00