[PATCH v2 4/7] cmdline: Add capability to prepend the command line

From: Christophe Leroy
Date: Tue Mar 02 2021 - 15:53:05 EST


This patchs adds an option of prepend a text to the command
line instead of appending it.

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
---
include/linux/cmdline.h | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/include/linux/cmdline.h b/include/linux/cmdline.h
index ae3610bb0ee2..144346051e01 100644
--- a/include/linux/cmdline.h
+++ b/include/linux/cmdline.h
@@ -31,7 +31,7 @@ static __always_inline size_t cmdline_strlcat(char *dest, const char *src, size_
}

/*
- * This function will append a builtin command line to the command
+ * This function will append or prepend a builtin command line to the command
* line provided by the bootloader. Kconfig options can be used to alter
* the behavior of this builtin command line.
* @dest: The destination of the final appended/prepended string.
@@ -50,6 +50,9 @@ static __always_inline void cmdline_build(char *dest, const char *src, size_t le
cmdline_strlcat(dest, CONFIG_CMDLINE, length);
return;
}
+
+ if (IS_ENABLED(CONFIG_CMDLINE_PREPEND) && sizeof(CONFIG_CMDLINE) > 1)
+ cmdline_strlcat(dest, CONFIG_CMDLINE " ", length);
#endif
if (dest != src)
cmdline_strlcat(dest, src, length);
--
2.25.0