[tip: sched/rt] proc: Add nbcon support for /proc/consoles

[tip-bot2 for John Ogness]

The following commit has been merged into the sched/rt branch of tip:

Commit-ID:     c83a20662dd099dbac9ef6df44134ef446980c56
Gitweb:        https://git.kernel.org/tip/c83a20662dd099dbac9ef6df44134ef446980c56
Author:        John Ogness <john.ogness@xxxxxxxxxxxxx>
AuthorDate:    Wed, 04 Sep 2024 14:11:32 +02:06
Committer:     Petr Mladek <pmladek@xxxxxxxx>
CommitterDate: Wed, 04 Sep 2024 15:56:33 +02:00

proc: Add nbcon support for /proc/consoles

Update /proc/consoles output to show 'W' if an nbcon console is
registered. Since the write_thread() callback is mandatory, it
enough just to check if it is an nbcon console.

Also update /proc/consoles output to show 'N' if it is an
nbcon console.

Signed-off-by: John Ogness <john.ogness@xxxxxxxxxxxxx>
Reviewed-by: Petr Mladek <pmladek@xxxxxxxx>
Link: https://lore.kernel.org/r/20240904120536.115780-14-john.ogness@xxxxxxxxxxxxx
Signed-off-by: Petr Mladek <pmladek@xxxxxxxx>
---
 fs/proc/consoles.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/fs/proc/consoles.c b/fs/proc/consoles.c
index 7036fdf..b7cab1a 100644
--- a/fs/proc/consoles.c
+++ b/fs/proc/consoles.c
@@ -21,6 +21,7 @@ static int show_console_dev(struct seq_file *m, void *v)
 		{ CON_ENABLED,		'E' },
 		{ CON_CONSDEV,		'C' },
 		{ CON_BOOT,		'B' },
+		{ CON_NBCON,		'N' },
 		{ CON_PRINTBUFFER,	'p' },
 		{ CON_BRL,		'b' },
 		{ CON_ANYTIME,		'a' },
@@ -58,8 +59,8 @@ static int show_console_dev(struct seq_file *m, void *v)
 	seq_printf(m, "%s%d", con->name, con->index);
 	seq_pad(m, ' ');
 	seq_printf(m, "%c%c%c (%s)", con->read ? 'R' : '-',
-			con->write ? 'W' : '-', con->unblank ? 'U' : '-',
-			flags);
+		   ((con->flags & CON_NBCON) || con->write) ? 'W' : '-',
+		   con->unblank ? 'U' : '-', flags);
 	if (dev)
 		seq_printf(m, " %4d:%d", MAJOR(dev), MINOR(dev));