s390/sclp: avoid merged message output
The sclp console and tty code currently uses several message text
objects in a single message event to print several lines with one
SCCB. This causes the output of these lines to be fused into a
block which is noticeable when selecting text in the operating system
message panel.
Instead use several message events with a single message text object
each to print every line on its own. This changes the SCCB layout
from
struct sccb_header
struct evbuf_header
struct mdb_header
struct go
struct mto
...
struct mto
to
struct sccb_header
struct evbuf_header
struct mdb_header
struct go
struct mto
...
struct evbuf_header
struct mdb_header
struct go
struct mto
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/char/sclp_tty.c b/drivers/s390/char/sclp_tty.c
index 0036632..3c6e174 100644
--- a/drivers/s390/char/sclp_tty.c
+++ b/drivers/s390/char/sclp_tty.c
@@ -84,8 +84,8 @@
* to change as output buffers get emptied, or if the output flow
* control is acted. This is not an exact number because not every
* character needs the same space in the sccb. The worst case is
- * a string of newlines. Every newlines creates a new mto which
- * needs 8 bytes.
+ * a string of newlines. Every newline creates a new message which
+ * needs 82 bytes.
*/
static int
sclp_tty_write_room (struct tty_struct *tty)
@@ -97,9 +97,9 @@
spin_lock_irqsave(&sclp_tty_lock, flags);
count = 0;
if (sclp_ttybuf != NULL)
- count = sclp_buffer_space(sclp_ttybuf) / sizeof(struct mto);
+ count = sclp_buffer_space(sclp_ttybuf) / sizeof(struct msg_buf);
list_for_each(l, &sclp_tty_pages)
- count += NR_EMPTY_MTO_PER_SCCB;
+ count += NR_EMPTY_MSG_PER_SCCB;
spin_unlock_irqrestore(&sclp_tty_lock, flags);
return count;
}