tty: Convert tty_buffer flags to bool

The struct tty_buffer has flags which is only used for storing TTYB_NORMAL.
There is also a few quite confusing operations for checking the presense
of TTYB_NORMAL. Simplify things by converting flags to bool.

Despite the name remaining the same, the meaning of "flags" is altered
slightly by this change. Previously it referred to flags of the buffer
(only TTYB_NORMAL being used as a flag). After this change, flags tell
whether the buffer contains/should be allocated with flags array along
with character data array. It is much more suitable name that
TTYB_NORMAL was for this purpose, thus the name remains.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20221019105504.16800-1-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 1 insertions, 4 deletions

diff --git a/include/linux/tty_buffer.h b/include/linux/tty_buffer.h
index 1796648c2907..6ceb2789e6c8 100644
--- a/include/linux/tty_buffer.h
+++ b/include/linux/tty_buffer.h
@@ -17,14 +17,11 @@ struct tty_buffer {
 	int commit;
 	int lookahead;		/* Lazy update on recv, can become less than "read" */
 	int read;
-	int flags;
+	bool flags;
 	/* Data points here */
 	unsigned long data[];
 };
 
-/* Values for .flags field of tty_buffer */
-#define TTYB_NORMAL	1	/* buffer has no flags buffer */
-
 static inline unsigned char *char_buf_ptr(struct tty_buffer *b, int ofs)
 {
 	return ((unsigned char *)b->data) + ofs;