printk: nbcon: Export nbcon_write_context_set_buf

This function will be used in the next patch to allow a driver to set
both the message and message length of a nbcon_write_context. This is
necessary because the function also initializes the ->unsafe_takeover
struct member. By using this helper we ensure that the struct is
initialized correctly.

Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
Link: https://patch.msgid.link/20251016-nbcon-kgdboc-v6-4-866aac60a80e@suse.com
Signed-off-by: Petr Mladek <pmladek@suse.com>

diff --git a/include/linux/console.h b/include/linux/console.h
index 9406342b27db463a4d0445a539c80a2729c5cb6b..4585eb8e109ecbbc1df6158cbc6215b03559a389 100644 (file)
--- a/include/linux/console.h
+++ b/include/linux/console.h
@@ -603,6 +603,8 @@ static inline bool console_is_registered(const struct console *con)
 extern void nbcon_cpu_emergency_enter(void);
 extern void nbcon_cpu_emergency_exit(void);
 extern bool nbcon_can_proceed(struct nbcon_write_context *wctxt);
+extern void nbcon_write_context_set_buf(struct nbcon_write_context *wctxt,
+                                       char *buf, unsigned int len);
 extern bool nbcon_enter_unsafe(struct nbcon_write_context *wctxt);
 extern bool nbcon_exit_unsafe(struct nbcon_write_context *wctxt);
 extern void nbcon_reacquire_nobuf(struct nbcon_write_context *wctxt);
@@ -655,6 +657,8 @@ static inline bool console_is_usable(struct console *con, short flags, bool use_
 static inline void nbcon_cpu_emergency_enter(void) { }
 static inline void nbcon_cpu_emergency_exit(void) { }
 static inline bool nbcon_can_proceed(struct nbcon_write_context *wctxt) { return false; }
+static inline void nbcon_write_context_set_buf(struct nbcon_write_context *wctxt,
+                                              char *buf, unsigned int len) { }
 static inline bool nbcon_enter_unsafe(struct nbcon_write_context *wctxt) { return false; }
 static inline bool nbcon_exit_unsafe(struct nbcon_write_context *wctxt) { return false; }
 static inline void nbcon_reacquire_nobuf(struct nbcon_write_context *wctxt) { }

diff --git a/kernel/printk/nbcon.c b/kernel/printk/nbcon.c
index 5be0184939098494bf61830a3de5f93ea856bcd7..fdd1cbebe77d8e2306474c3c3b7cce0f3ec9156e 100644 (file)
--- a/kernel/printk/nbcon.c
+++ b/kernel/printk/nbcon.c
@@ -854,8 +854,8 @@ out:
        return nbcon_context_can_proceed(ctxt, &cur);
 }
 
-static void nbcon_write_context_set_buf(struct nbcon_write_context *wctxt,
-                                       char *buf, unsigned int len)
+void nbcon_write_context_set_buf(struct nbcon_write_context *wctxt,
+                                char *buf, unsigned int len)
 {
        struct nbcon_context *ctxt = &ACCESS_PRIVATE(wctxt, ctxt);
        struct console *con = ctxt->console;