summaryrefslogtreecommitdiffstats
path: root/drivers/char/pty.c
diff options
context:
space:
mode:
authorFrederic Weisbecker2009-10-18 01:09:09 +0200
committerFrederic Weisbecker2009-10-18 01:12:33 +0200
commit0f8f86c7bdd1c954fbe153af437a0d91a6c5721a (patch)
tree94a8d419a470a4f9852ca397bb9bbe48db92ff5c /drivers/char/pty.c
parentMerge branch 'linus' into tracing/hw-breakpoints (diff)
parentperf tools: Move dereference after NULL test (diff)
downloadkernel-qcow2-linux-0f8f86c7bdd1c954fbe153af437a0d91a6c5721a.tar.gz
kernel-qcow2-linux-0f8f86c7bdd1c954fbe153af437a0d91a6c5721a.tar.xz
kernel-qcow2-linux-0f8f86c7bdd1c954fbe153af437a0d91a6c5721a.zip
Merge commit 'perf/core' into perf/hw-breakpoint
Conflicts: kernel/Makefile kernel/trace/Makefile kernel/trace/trace.h samples/Makefile Merge reason: We need to be uptodate with the perf events development branch because we plan to rewrite the breakpoints API on top of perf events.
Diffstat (limited to 'drivers/char/pty.c')
-rw-r--r--drivers/char/pty.c54
1 files changed, 31 insertions, 23 deletions
diff --git a/drivers/char/pty.c b/drivers/char/pty.c
index b33d6688e910..62f282e67638 100644
--- a/drivers/char/pty.c
+++ b/drivers/char/pty.c
@@ -18,6 +18,7 @@
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/fcntl.h>
+#include <linux/sched.h>
#include <linux/string.h>
#include <linux/major.h>
#include <linux/mm.h>
@@ -120,8 +121,10 @@ static int pty_write(struct tty_struct *tty, const unsigned char *buf, int c)
/* Stuff the data into the input queue of the other end */
c = tty_insert_flip_string(to, buf, c);
/* And shovel */
- tty_flip_buffer_push(to);
- tty_wakeup(tty);
+ if (c) {
+ tty_flip_buffer_push(to);
+ tty_wakeup(tty);
+ }
}
return c;
}
@@ -259,6 +262,9 @@ done:
return 0;
}
+/* Traditional BSD devices */
+#ifdef CONFIG_LEGACY_PTYS
+
static int pty_install(struct tty_driver *driver, struct tty_struct *tty)
{
struct tty_struct *o_tty;
@@ -308,24 +314,6 @@ free_mem_out:
return -ENOMEM;
}
-
-static const struct tty_operations pty_ops = {
- .install = pty_install,
- .open = pty_open,
- .close = pty_close,
- .write = pty_write,
- .write_room = pty_write_room,
- .flush_buffer = pty_flush_buffer,
- .chars_in_buffer = pty_chars_in_buffer,
- .unthrottle = pty_unthrottle,
- .set_termios = pty_set_termios,
- .resize = pty_resize
-};
-
-/* Traditional BSD devices */
-#ifdef CONFIG_LEGACY_PTYS
-static struct tty_driver *pty_driver, *pty_slave_driver;
-
static int pty_bsd_ioctl(struct tty_struct *tty, struct file *file,
unsigned int cmd, unsigned long arg)
{
@@ -339,7 +327,12 @@ static int pty_bsd_ioctl(struct tty_struct *tty, struct file *file,
static int legacy_count = CONFIG_LEGACY_PTY_COUNT;
module_param(legacy_count, int, 0);
-static const struct tty_operations pty_ops_bsd = {
+/*
+ * The master side of a pty can do TIOCSPTLCK and thus
+ * has pty_bsd_ioctl.
+ */
+static const struct tty_operations master_pty_ops_bsd = {
+ .install = pty_install,
.open = pty_open,
.close = pty_close,
.write = pty_write,
@@ -352,8 +345,23 @@ static const struct tty_operations pty_ops_bsd = {
.resize = pty_resize
};
+static const struct tty_operations slave_pty_ops_bsd = {
+ .install = pty_install,
+ .open = pty_open,
+ .close = pty_close,
+ .write = pty_write,
+ .write_room = pty_write_room,
+ .flush_buffer = pty_flush_buffer,
+ .chars_in_buffer = pty_chars_in_buffer,
+ .unthrottle = pty_unthrottle,
+ .set_termios = pty_set_termios,
+ .resize = pty_resize
+};
+
static void __init legacy_pty_init(void)
{
+ struct tty_driver *pty_driver, *pty_slave_driver;
+
if (legacy_count <= 0)
return;
@@ -381,7 +389,7 @@ static void __init legacy_pty_init(void)
pty_driver->init_termios.c_ospeed = 38400;
pty_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW;
pty_driver->other = pty_slave_driver;
- tty_set_operations(pty_driver, &pty_ops);
+ tty_set_operations(pty_driver, &master_pty_ops_bsd);
pty_slave_driver->owner = THIS_MODULE;
pty_slave_driver->driver_name = "pty_slave";
@@ -397,7 +405,7 @@ static void __init legacy_pty_init(void)
pty_slave_driver->flags = TTY_DRIVER_RESET_TERMIOS |
TTY_DRIVER_REAL_RAW;
pty_slave_driver->other = pty_driver;
- tty_set_operations(pty_slave_driver, &pty_ops);
+ tty_set_operations(pty_slave_driver, &slave_pty_ops_bsd);
if (tty_register_driver(pty_driver))
panic("Couldn't register pty driver");