Add a tty code to indicate a resize frame. The body contains two big
endian 16-bit integers rows and columns.
After reset, the guest must be informed of the terminal size again. A
chardev that doesn't report its size yields 0x0, which shouldn't replace
the guest's default.
Signed-off-by: Maximilian Immanuel Brandtner <[email protected]>
---
Changelog:
v2:
- Use packed struct and named event type codes for resize frames
- Trigger initial resize event in console_reset() instead of
console_init(), skip when chardev reports no size
- Reset event_pending after resize event
Requires the following pre-req:
[PATCH v7 00/12] virtio-console: notify about the terminal size
(https://lore.kernel.org/qemu-devel/[email protected]/)
Testing:
- Tested on QEMU: commit 38879a667f with the following patches applied:
[PATCH v7 00/12] virtio-console: notify about the terminal size
- Tested on linux-next (commit c1f49dea2b8f) with the following patches
applied:
[PATCH 0/2] s390/sclp: Resize for sclp-vt220 console
---
hw/char/sclpconsole.c | 92 +++++++++++++++++++++++++++++++++++++------
1 file changed, 80 insertions(+), 12 deletions(-)
diff --git a/hw/char/sclpconsole.c b/hw/char/sclpconsole.c
index 179d12745c..12033e1e46 100644
--- a/hw/char/sclpconsole.c
+++ b/hw/char/sclpconsole.c
@@ -33,6 +33,9 @@ typedef struct ASCIIConsoleData {
/* max size for ASCII data in 4K SCCB page */
#define SIZE_BUFFER_VT220 4080
+#define SCLP_CONSOLE_EVENT_TYPE_DATA 0x00
+#define SCLP_CONSOLE_EVENT_TYPE_RESIZE 0x08
+
struct SCLPConsole {
SCLPEvent event;
CharFrontend chr;
@@ -42,6 +45,8 @@ struct SCLPConsole {
uint32_t iov_data_len; /* length of byte stream in buffer */
uint32_t iov_sclp_rest; /* length of byte stream not read via SCLP */
bool notify; /* qemu_notify_event() req'd if true */
+ bool resize;
+ bool resize_init;
};
typedef struct SCLPConsole SCLPConsole;
@@ -49,6 +54,12 @@ typedef struct SCLPConsole SCLPConsole;
DECLARE_INSTANCE_CHECKER(SCLPConsole, SCLP_CONSOLE,
TYPE_SCLP_CONSOLE)
+typedef struct SCLPConsoleResizeData {
+ uint8_t type;
+ uint16_t rows;
+ uint16_t cols;
+} QEMU_PACKED SCLPConsoleResizeData;
+
/* character layer call-back functions */
/* Return number of bytes that fit into iov buffer */
@@ -81,6 +92,29 @@ static void chr_read(void *opaque, const uint8_t *buf, int
size)
sclp_service_interrupt(0);
}
+static void chr_event(void *opaque, QEMUChrEvent event)
+{
+ SCLPConsole *scon = opaque;
+
+ assert(scon);
+
+ switch (event) {
+ case CHR_EVENT_RESIZE:
+ case CHR_EVENT_MUX_IN:
+ scon->resize = true;
+ scon->resize_init = false;
+ scon->event.event_pending = true;
+ sclp_service_interrupt(0);
+ break;
+ case CHR_EVENT_BREAK:
+ case CHR_EVENT_OPENED:
+ case CHR_EVENT_MUX_OUT:
+ case CHR_EVENT_CLOSED:
+ /* ignore */
+ break;
+ }
+}
+
/* functions to be called by event facility */
static bool can_handle_event(uint8_t type)
@@ -104,10 +138,37 @@ static sccb_mask_t receive_mask(void)
static void get_console_data(SCLPEvent *event, uint8_t *buf, size_t *size,
int avail)
{
+ SCLPConsoleResizeData resize_data;
SCLPConsole *cons = SCLP_CONSOLE(event);
+ uint16_t rows, cols;
+
+ if (cons->resize) {
+ if (avail < sizeof(resize_data)) {
+ *size = 0;
+ return;
+ }
- /* first byte is hex 0 saying an ascii string follows */
- *buf++ = '\0';
+ qemu_chr_fe_get_winsize(&cons->chr, &cols, &rows);
+
+ if (cons->resize_init && cols == 0 && rows == 0) {
+ *size = 0;
+ } else {
+ resize_data.type = SCLP_CONSOLE_EVENT_TYPE_RESIZE;
+ resize_data.rows = cpu_to_be16(rows);
+ resize_data.cols = cpu_to_be16(cols);
+
+ memcpy(buf, &resize_data, sizeof(resize_data));
+ *size = sizeof(resize_data);
+ }
+
+ cons->resize = false;
+ cons->resize_init = false;
+ event->event_pending = cons->iov_sclp_rest != 0;
+
+ return;
+ }
+
+ *buf++ = SCLP_CONSOLE_EVENT_TYPE_DATA;
avail--;
/* if all data fit into provided SCLP buffer */
if (avail >= cons->iov_sclp_rest) {
@@ -150,6 +211,9 @@ static int read_event_data(SCLPEvent *event,
EventBufferHeader *evt_buf_hdr,
to = (uint8_t *)&acd->data;
avail = *slen - sizeof(ASCIIConsoleData);
get_console_data(event, to, &src_len, avail);
+ if (src_len == 0) {
+ return 0;
+ }
acd->ebh.length = cpu_to_be16(sizeof(ASCIIConsoleData) + src_len);
acd->ebh.type = SCLP_EVENT_ASCII_CONSOLE_DATA;
@@ -233,22 +297,26 @@ static int console_init(SCLPEvent *event)
}
console_available = true;
qemu_chr_fe_set_handlers(&scon->chr, chr_can_read,
- chr_read, NULL, NULL, scon, NULL, true);
+ chr_read, chr_event, NULL, scon, NULL, true);
return 0;
}
static void console_reset(DeviceState *dev)
{
- SCLPEvent *event = SCLP_EVENT(dev);
- SCLPConsole *scon = SCLP_CONSOLE(event);
-
- event->event_pending = false;
- scon->iov_sclp = 0;
- scon->iov_bs = 0;
- scon->iov_data_len = 0;
- scon->iov_sclp_rest = 0;
- scon->notify = false;
+ SCLPEvent *event = SCLP_EVENT(dev);
+ SCLPConsole *scon = SCLP_CONSOLE(event);
+
+ scon->iov_sclp = 0;
+ scon->iov_bs = 0;
+ scon->iov_data_len = 0;
+ scon->iov_sclp_rest = 0;
+ scon->notify = false;
+
+ /* the guest defaults its terminal size on reset, announce the real one */
+ scon->resize = true;
+ scon->resize_init = true;
+ event->event_pending = true;
}
