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path: root/drivers/s390/char/sclp_vt220.c
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Diffstat (limited to 'drivers/s390/char/sclp_vt220.c')
-rw-r--r--drivers/s390/char/sclp_vt220.c92
1 files changed, 57 insertions, 35 deletions
diff --git a/drivers/s390/char/sclp_vt220.c b/drivers/s390/char/sclp_vt220.c
index 5d706e6c946..b9a9f721716 100644
--- a/drivers/s390/char/sclp_vt220.c
+++ b/drivers/s390/char/sclp_vt220.c
@@ -34,7 +34,6 @@
#define SCLP_VT220_DEVICE_NAME "ttysclp"
#define SCLP_VT220_CONSOLE_NAME "ttyS"
#define SCLP_VT220_CONSOLE_INDEX 1 /* console=ttyS1 */
-#define SCLP_VT220_BUF_SIZE 80
/* Representation of a single write request */
struct sclp_vt220_request {
@@ -56,8 +55,7 @@ struct sclp_vt220_sccb {
/* Structures and data needed to register tty driver */
static struct tty_driver *sclp_vt220_driver;
-/* The tty_struct that the kernel associated with us */
-static struct tty_struct *sclp_vt220_tty;
+static struct tty_port sclp_vt220_port;
/* Lock to protect internal data from concurrent access */
static spinlock_t sclp_vt220_lock;
@@ -99,13 +97,16 @@ static void sclp_vt220_pm_event_fn(struct sclp_register *reg,
static int __sclp_vt220_emit(struct sclp_vt220_request *request);
static void sclp_vt220_emit_current(void);
-/* Registration structure for our interest in SCLP event buffers */
+/* Registration structure for SCLP output event buffers */
static struct sclp_register sclp_vt220_register = {
.send_mask = EVTYP_VT220MSG_MASK,
+ .pm_event_fn = sclp_vt220_pm_event_fn,
+};
+
+/* Registration structure for SCLP input event buffers */
+static struct sclp_register sclp_vt220_register_input = {
.receive_mask = EVTYP_VT220MSG_MASK,
- .state_change_fn = NULL,
.receiver_fn = sclp_vt220_receiver_fn,
- .pm_event_fn = sclp_vt220_pm_event_fn,
};
@@ -140,10 +141,7 @@ sclp_vt220_process_queue(struct sclp_vt220_request *request)
} while (__sclp_vt220_emit(request));
if (request == NULL && sclp_vt220_flush_later)
sclp_vt220_emit_current();
- /* Check if the tty needs a wake up call */
- if (sclp_vt220_tty != NULL) {
- tty_wakeup(sclp_vt220_tty);
- }
+ tty_port_tty_wakeup(&sclp_vt220_port);
}
#define SCLP_BUFFER_MAX_RETRY 1
@@ -367,6 +365,31 @@ sclp_vt220_timeout(unsigned long data)
#define BUFFER_MAX_DELAY HZ/20
+/*
+ * Drop oldest console buffer if sclp_con_drop is set
+ */
+static int
+sclp_vt220_drop_buffer(void)
+{
+ struct list_head *list;
+ struct sclp_vt220_request *request;
+ void *page;
+
+ if (!sclp_console_drop)
+ return 0;
+ list = sclp_vt220_outqueue.next;
+ if (sclp_vt220_queue_running)
+ /* The first element is in I/O */
+ list = list->next;
+ if (list == &sclp_vt220_outqueue)
+ return 0;
+ list_del(list);
+ request = list_entry(list, struct sclp_vt220_request, list);
+ page = request->sclp_req.sccb;
+ list_add_tail((struct list_head *) page, &sclp_vt220_empty);
+ return 1;
+}
+
/*
* Internal implementation of the write function. Write COUNT bytes of data
* from memory at BUF
@@ -395,12 +418,16 @@ __sclp_vt220_write(const unsigned char *buf, int count, int do_schedule,
do {
/* Create an sclp output buffer if none exists yet */
if (sclp_vt220_current_request == NULL) {
+ if (list_empty(&sclp_vt220_empty))
+ sclp_console_full++;
while (list_empty(&sclp_vt220_empty)) {
- spin_unlock_irqrestore(&sclp_vt220_lock, flags);
if (may_fail || sclp_vt220_suspended)
goto out;
- else
- sclp_sync_wait();
+ if (sclp_vt220_drop_buffer())
+ break;
+ spin_unlock_irqrestore(&sclp_vt220_lock, flags);
+
+ sclp_sync_wait();
spin_lock_irqsave(&sclp_vt220_lock, flags);
}
page = (void *) sclp_vt220_empty.next;
@@ -433,8 +460,8 @@ __sclp_vt220_write(const unsigned char *buf, int count, int do_schedule,
sclp_vt220_timer.expires = jiffies + BUFFER_MAX_DELAY;
add_timer(&sclp_vt220_timer);
}
- spin_unlock_irqrestore(&sclp_vt220_lock, flags);
out:
+ spin_unlock_irqrestore(&sclp_vt220_lock, flags);
return overall_written;
}
@@ -463,10 +490,6 @@ sclp_vt220_receiver_fn(struct evbuf_header *evbuf)
char *buffer;
unsigned int count;
- /* Ignore input if device is not open */
- if (sclp_vt220_tty == NULL)
- return;
-
buffer = (char *) ((addr_t) evbuf + sizeof(struct evbuf_header));
count = evbuf->length - sizeof(struct evbuf_header);
@@ -478,8 +501,8 @@ sclp_vt220_receiver_fn(struct evbuf_header *evbuf)
/* Send input to line discipline */
buffer++;
count--;
- tty_insert_flip_string(sclp_vt220_tty, buffer, count);
- tty_flip_buffer_push(sclp_vt220_tty);
+ tty_insert_flip_string(&sclp_vt220_port, buffer, count);
+ tty_flip_buffer_push(&sclp_vt220_port);
break;
}
}
@@ -491,11 +514,8 @@ static int
sclp_vt220_open(struct tty_struct *tty, struct file *filp)
{
if (tty->count == 1) {
- sclp_vt220_tty = tty;
- tty->driver_data = kmalloc(SCLP_VT220_BUF_SIZE, GFP_KERNEL);
- if (tty->driver_data == NULL)
- return -ENOMEM;
- tty->low_latency = 0;
+ tty_port_tty_set(&sclp_vt220_port, tty);
+ sclp_vt220_port.low_latency = 0;
if (!tty->winsize.ws_row && !tty->winsize.ws_col) {
tty->winsize.ws_row = 24;
tty->winsize.ws_col = 80;
@@ -510,11 +530,8 @@ sclp_vt220_open(struct tty_struct *tty, struct file *filp)
static void
sclp_vt220_close(struct tty_struct *tty, struct file *filp)
{
- if (tty->count == 1) {
- sclp_vt220_tty = NULL;
- kfree(tty->driver_data);
- tty->driver_data = NULL;
- }
+ if (tty->count == 1)
+ tty_port_tty_set(&sclp_vt220_port, NULL);
}
/*
@@ -618,6 +635,7 @@ static void __init __sclp_vt220_cleanup(void)
return;
sclp_unregister(&sclp_vt220_register);
__sclp_vt220_free_pages();
+ tty_port_destroy(&sclp_vt220_port);
}
/* Allocate buffer pages and register with sclp core. Controlled by init
@@ -635,9 +653,9 @@ static int __init __sclp_vt220_init(int num_pages)
INIT_LIST_HEAD(&sclp_vt220_empty);
INIT_LIST_HEAD(&sclp_vt220_outqueue);
init_timer(&sclp_vt220_timer);
+ tty_port_init(&sclp_vt220_port);
sclp_vt220_current_request = NULL;
sclp_vt220_buffered_chars = 0;
- sclp_vt220_tty = NULL;
sclp_vt220_flush_later = 0;
/* Allocate pages for output buffering */
@@ -653,6 +671,7 @@ out:
if (rc) {
__sclp_vt220_free_pages();
sclp_vt220_init_count--;
+ tty_port_destroy(&sclp_vt220_port);
}
return rc;
}
@@ -685,7 +704,6 @@ static int __init sclp_vt220_tty_init(void)
if (rc)
goto out_driver;
- driver->owner = THIS_MODULE;
driver->driver_name = SCLP_VT220_DRIVER_NAME;
driver->name = SCLP_VT220_DEVICE_NAME;
driver->major = SCLP_VT220_MAJOR;
@@ -695,13 +713,19 @@ static int __init sclp_vt220_tty_init(void)
driver->init_termios = tty_std_termios;
driver->flags = TTY_DRIVER_REAL_RAW;
tty_set_operations(driver, &sclp_vt220_ops);
+ tty_port_link_device(&sclp_vt220_port, driver, 0);
rc = tty_register_driver(driver);
if (rc)
goto out_init;
+ rc = sclp_register(&sclp_vt220_register_input);
+ if (rc)
+ goto out_reg;
sclp_vt220_driver = driver;
return 0;
+out_reg:
+ tty_unregister_driver(driver);
out_init:
__sclp_vt220_cleanup();
out_driver:
@@ -814,9 +838,7 @@ sclp_vt220_con_init(void)
{
int rc;
- if (!CONSOLE_IS_SCLP)
- return 0;
- rc = __sclp_vt220_init(MAX_CONSOLE_PAGES);
+ rc = __sclp_vt220_init(sclp_console_pages);
if (rc)
return rc;
/* Attach linux console */
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-09 13:04:09 +0000