[PATCH v3 1/2] printk: console: Create console= parser that supports named options

Chris Down
2022-07-20T17:48:20Z

This will be used in the next patch, and for future changes like the
proposed sync/nothread named options. This avoids having to use sigils
like "/" to get different semantic meaning for different parts of the
option string, and helps to make things more human readable and
easily extensible.

There are no functional changes for existing console= users.

Signed-off-by: Chris Down <chris@chrisdown.name>
---
kernel/printk/printk.c | 26 +++++++++++++++++++++++++-
1 file changed, 25 insertions(+), 1 deletion(-)

diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index b49c6ff6dca0..6094f773ad4a 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -2368,6 +2368,30 @@ static void set_user_specified(struct console_cmdline *c, bool user_specified)
console_set_on_cmdline = 1;
}

+static void parse_console_cmdline_options(struct console_cmdline *c,
+ char *options)
+{
+ bool seen_serial_opts = false;
+ char *key;
+
+ while ((key = strsep(&options, ",")) != NULL) {
+ char *value;
+
+ value = strchr(key, ':');
+ if (value)
+ *(value++) = '\0';
+
+ if (!seen_serial_opts && isdigit(key[0]) && !value) {
+ seen_serial_opts = true;
+ c->options = key;
+ continue;
+ }
+
+ pr_err("ignoring invalid console option: '%s%s%s'\n", key,
+ value ? ":" : "", value ?: "");
+ }
+}
+
static int __add_preferred_console(char *name, int idx, char *options,
char *brl_options, bool user_specified)
{
@@ -2393,7 +2417,7 @@ static int __add_preferred_console(char *name, int idx, char *options,
if (!brl_options)
preferred_console = i;
strlcpy(c->name, name, sizeof(c->name));
- c->options = options;
+ parse_console_cmdline_options(c, options);
set_user_specified(c, user_specified);
braille_set_options(c, brl_options);

--
2.37.1