[PATCH 7/8] tty: move tty_port to new tty_port.h

From: Jiri Slaby
Date: Fri Jul 23 2021 - 06:32:11 EST


tty.h is long enough already. And I am slowly adding kernel-doc
documentation, so it grows to unmaintainable long mess. To avoid this,
split tty.h further into tty_port.h and move there tty_port-related
declarations and function prototypes (those implemented in tty_port.c).

Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
include/linux/tty.h | 196 +-----------------------------------
include/linux/tty_port.h | 208 +++++++++++++++++++++++++++++++++++++++
2 files changed, 209 insertions(+), 195 deletions(-)
create mode 100644 include/linux/tty_port.h

diff --git a/include/linux/tty.h b/include/linux/tty.h
index b5f353797cec..168e57e40bbb 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -9,6 +9,7 @@
#include <linux/tty_buffer.h>
#include <linux/tty_driver.h>
#include <linux/tty_ldisc.h>
+#include <linux/tty_port.h>
#include <linux/mutex.h>
#include <linux/tty_flags.h>
#include <uapi/linux/tty.h>
@@ -116,85 +117,6 @@

struct device;
struct signal_struct;
-
-/*
- * Port level information. Each device keeps its own port level information
- * so provide a common structure for those ports wanting to use common support
- * routines.
- *
- * The tty port has a different lifetime to the tty so must be kept apart.
- * In addition be careful as tty -> port mappings are valid for the life
- * of the tty object but in many cases port -> tty mappings are valid only
- * until a hangup so don't use the wrong path.
- */
-
-struct tty_port;
-
-struct tty_port_operations {
- /* Return 1 if the carrier is raised */
- int (*carrier_raised)(struct tty_port *port);
- /* Control the DTR line */
- void (*dtr_rts)(struct tty_port *port, int raise);
- /* Called when the last close completes or a hangup finishes
- IFF the port was initialized. Do not use to free resources. Called
- under the port mutex to serialize against activate/shutdowns */
- void (*shutdown)(struct tty_port *port);
- /* Called under the port mutex from tty_port_open, serialized using
- the port mutex */
- /* FIXME: long term getting the tty argument *out* of this would be
- good for consoles */
- int (*activate)(struct tty_port *port, struct tty_struct *tty);
- /* Called on the final put of a port */
- void (*destruct)(struct tty_port *port);
-};
-
-struct tty_port_client_operations {
- int (*receive_buf)(struct tty_port *port, const unsigned char *, const unsigned char *, size_t);
- void (*write_wakeup)(struct tty_port *port);
-};
-
-extern const struct tty_port_client_operations tty_port_default_client_ops;
-
-struct tty_port {
- struct tty_bufhead buf; /* Locked internally */
- struct tty_struct *tty; /* Back pointer */
- struct tty_struct *itty; /* internal back ptr */
- const struct tty_port_operations *ops; /* Port operations */
- const struct tty_port_client_operations *client_ops; /* Port client operations */
- spinlock_t lock; /* Lock protecting tty field */
- int blocked_open; /* Waiting to open */
- int count; /* Usage count */
- wait_queue_head_t open_wait; /* Open waiters */
- wait_queue_head_t delta_msr_wait; /* Modem status change */
- unsigned long flags; /* User TTY flags ASYNC_ */
- unsigned long iflags; /* Internal flags TTY_PORT_ */
- unsigned char console:1; /* port is a console */
- struct mutex mutex; /* Locking */
- struct mutex buf_mutex; /* Buffer alloc lock */
- unsigned char *xmit_buf; /* Optional buffer */
- unsigned int close_delay; /* Close port delay */
- unsigned int closing_wait; /* Delay for output */
- int drain_delay; /* Set to zero if no pure time
- based drain is needed else
- set to size of fifo */
- struct kref kref; /* Ref counter */
- void *client_data;
-};
-
-/* tty_port::iflags bits -- use atomic bit ops */
-#define TTY_PORT_INITIALIZED 0 /* device is initialized */
-#define TTY_PORT_SUSPENDED 1 /* device is suspended */
-#define TTY_PORT_ACTIVE 2 /* device is open */
-
-/*
- * uart drivers: use the uart_port::status field and the UPSTAT_* defines
- * for s/w-based flow control steering and carrier detection status
- */
-#define TTY_PORT_CTS_FLOW 3 /* h/w flow control enabled */
-#define TTY_PORT_CHECK_CD 4 /* carrier detect enabled */
-#define TTY_PORT_KOPENED 5 /* device exclusively opened by
- kernel */
-
struct tty_operations;

/**
@@ -459,122 +381,6 @@ extern int tty_standard_install(struct tty_driver *driver,

extern struct mutex tty_mutex;

-extern void tty_port_init(struct tty_port *port);
-extern void tty_port_link_device(struct tty_port *port,
- struct tty_driver *driver, unsigned index);
-extern struct device *tty_port_register_device(struct tty_port *port,
- struct tty_driver *driver, unsigned index,
- struct device *device);
-extern struct device *tty_port_register_device_attr(struct tty_port *port,
- struct tty_driver *driver, unsigned index,
- struct device *device, void *drvdata,
- const struct attribute_group **attr_grp);
-extern struct device *tty_port_register_device_serdev(struct tty_port *port,
- struct tty_driver *driver, unsigned index,
- struct device *device);
-extern struct device *tty_port_register_device_attr_serdev(struct tty_port *port,
- struct tty_driver *driver, unsigned index,
- struct device *device, void *drvdata,
- const struct attribute_group **attr_grp);
-extern void tty_port_unregister_device(struct tty_port *port,
- struct tty_driver *driver, unsigned index);
-extern int tty_port_alloc_xmit_buf(struct tty_port *port);
-extern void tty_port_free_xmit_buf(struct tty_port *port);
-extern void tty_port_destroy(struct tty_port *port);
-extern void tty_port_put(struct tty_port *port);
-
-static inline struct tty_port *tty_port_get(struct tty_port *port)
-{
- if (port && kref_get_unless_zero(&port->kref))
- return port;
- return NULL;
-}
-
-/* If the cts flow control is enabled, return true. */
-static inline bool tty_port_cts_enabled(const struct tty_port *port)
-{
- return test_bit(TTY_PORT_CTS_FLOW, &port->iflags);
-}
-
-static inline void tty_port_set_cts_flow(struct tty_port *port, bool val)
-{
- assign_bit(TTY_PORT_CTS_FLOW, &port->iflags, val);
-}
-
-static inline bool tty_port_active(const struct tty_port *port)
-{
- return test_bit(TTY_PORT_ACTIVE, &port->iflags);
-}
-
-static inline void tty_port_set_active(struct tty_port *port, bool val)
-{
- assign_bit(TTY_PORT_ACTIVE, &port->iflags, val);
-}
-
-static inline bool tty_port_check_carrier(const struct tty_port *port)
-{
- return test_bit(TTY_PORT_CHECK_CD, &port->iflags);
-}
-
-static inline void tty_port_set_check_carrier(struct tty_port *port, bool val)
-{
- assign_bit(TTY_PORT_CHECK_CD, &port->iflags, val);
-}
-
-static inline bool tty_port_suspended(const struct tty_port *port)
-{
- return test_bit(TTY_PORT_SUSPENDED, &port->iflags);
-}
-
-static inline void tty_port_set_suspended(struct tty_port *port, bool val)
-{
- assign_bit(TTY_PORT_SUSPENDED, &port->iflags, val);
-}
-
-static inline bool tty_port_initialized(const struct tty_port *port)
-{
- return test_bit(TTY_PORT_INITIALIZED, &port->iflags);
-}
-
-static inline void tty_port_set_initialized(struct tty_port *port, bool val)
-{
- assign_bit(TTY_PORT_INITIALIZED, &port->iflags, val);
-}
-
-static inline bool tty_port_kopened(const struct tty_port *port)
-{
- return test_bit(TTY_PORT_KOPENED, &port->iflags);
-}
-
-static inline void tty_port_set_kopened(struct tty_port *port, bool val)
-{
- assign_bit(TTY_PORT_KOPENED, &port->iflags, val);
-}
-
-extern struct tty_struct *tty_port_tty_get(struct tty_port *port);
-extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty);
-extern int tty_port_carrier_raised(struct tty_port *port);
-extern void tty_port_raise_dtr_rts(struct tty_port *port);
-extern void tty_port_lower_dtr_rts(struct tty_port *port);
-extern void tty_port_hangup(struct tty_port *port);
-extern void tty_port_tty_hangup(struct tty_port *port, bool check_clocal);
-extern void tty_port_tty_wakeup(struct tty_port *port);
-extern int tty_port_block_til_ready(struct tty_port *port,
- struct tty_struct *tty, struct file *filp);
-extern int tty_port_close_start(struct tty_port *port,
- struct tty_struct *tty, struct file *filp);
-extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty);
-extern void tty_port_close(struct tty_port *port,
- struct tty_struct *tty, struct file *filp);
-extern int tty_port_install(struct tty_port *port, struct tty_driver *driver,
- struct tty_struct *tty);
-extern int tty_port_open(struct tty_port *port,
- struct tty_struct *tty, struct file *filp);
-static inline int tty_port_users(struct tty_port *port)
-{
- return port->count + port->blocked_open;
-}
-
/* n_tty.c */
extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops);
#ifdef CONFIG_TTY
diff --git a/include/linux/tty_port.h b/include/linux/tty_port.h
new file mode 100644
index 000000000000..6e86e9e118b6
--- /dev/null
+++ b/include/linux/tty_port.h
@@ -0,0 +1,208 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_TTY_PORT_H
+#define _LINUX_TTY_PORT_H
+
+#include <linux/kref.h>
+#include <linux/mutex.h>
+#include <linux/tty_buffer.h>
+#include <linux/wait.h>
+
+/*
+ * Port level information. Each device keeps its own port level information
+ * so provide a common structure for those ports wanting to use common support
+ * routines.
+ *
+ * The tty port has a different lifetime to the tty so must be kept apart.
+ * In addition be careful as tty -> port mappings are valid for the life
+ * of the tty object but in many cases port -> tty mappings are valid only
+ * until a hangup so don't use the wrong path.
+ */
+
+struct attribute_group;
+struct tty_driver;
+struct tty_port;
+struct tty_struct;
+
+struct tty_port_operations {
+ /* Return 1 if the carrier is raised */
+ int (*carrier_raised)(struct tty_port *port);
+ /* Control the DTR line */
+ void (*dtr_rts)(struct tty_port *port, int raise);
+ /* Called when the last close completes or a hangup finishes
+ IFF the port was initialized. Do not use to free resources. Called
+ under the port mutex to serialize against activate/shutdowns */
+ void (*shutdown)(struct tty_port *port);
+ /* Called under the port mutex from tty_port_open, serialized using
+ the port mutex */
+ /* FIXME: long term getting the tty argument *out* of this would be
+ good for consoles */
+ int (*activate)(struct tty_port *port, struct tty_struct *tty);
+ /* Called on the final put of a port */
+ void (*destruct)(struct tty_port *port);
+};
+
+struct tty_port_client_operations {
+ int (*receive_buf)(struct tty_port *port, const unsigned char *, const unsigned char *, size_t);
+ void (*write_wakeup)(struct tty_port *port);
+};
+
+extern const struct tty_port_client_operations tty_port_default_client_ops;
+
+struct tty_port {
+ struct tty_bufhead buf; /* Locked internally */
+ struct tty_struct *tty; /* Back pointer */
+ struct tty_struct *itty; /* internal back ptr */
+ const struct tty_port_operations *ops; /* Port operations */
+ const struct tty_port_client_operations *client_ops; /* Port client operations */
+ spinlock_t lock; /* Lock protecting tty field */
+ int blocked_open; /* Waiting to open */
+ int count; /* Usage count */
+ wait_queue_head_t open_wait; /* Open waiters */
+ wait_queue_head_t delta_msr_wait; /* Modem status change */
+ unsigned long flags; /* User TTY flags ASYNC_ */
+ unsigned long iflags; /* Internal flags TTY_PORT_ */
+ unsigned char console:1; /* port is a console */
+ struct mutex mutex; /* Locking */
+ struct mutex buf_mutex; /* Buffer alloc lock */
+ unsigned char *xmit_buf; /* Optional buffer */
+ unsigned int close_delay; /* Close port delay */
+ unsigned int closing_wait; /* Delay for output */
+ int drain_delay; /* Set to zero if no pure time
+ based drain is needed else
+ set to size of fifo */
+ struct kref kref; /* Ref counter */
+ void *client_data;
+};
+
+/* tty_port::iflags bits -- use atomic bit ops */
+#define TTY_PORT_INITIALIZED 0 /* device is initialized */
+#define TTY_PORT_SUSPENDED 1 /* device is suspended */
+#define TTY_PORT_ACTIVE 2 /* device is open */
+
+/*
+ * uart drivers: use the uart_port::status field and the UPSTAT_* defines
+ * for s/w-based flow control steering and carrier detection status
+ */
+#define TTY_PORT_CTS_FLOW 3 /* h/w flow control enabled */
+#define TTY_PORT_CHECK_CD 4 /* carrier detect enabled */
+#define TTY_PORT_KOPENED 5 /* device exclusively opened by
+ kernel */
+
+void tty_port_init(struct tty_port *port);
+void tty_port_link_device(struct tty_port *port, struct tty_driver *driver,
+ unsigned index);
+struct device *tty_port_register_device(struct tty_port *port,
+ struct tty_driver *driver, unsigned index,
+ struct device *device);
+struct device *tty_port_register_device_attr(struct tty_port *port,
+ struct tty_driver *driver, unsigned index,
+ struct device *device, void *drvdata,
+ const struct attribute_group **attr_grp);
+struct device *tty_port_register_device_serdev(struct tty_port *port,
+ struct tty_driver *driver, unsigned index,
+ struct device *device);
+struct device *tty_port_register_device_attr_serdev(struct tty_port *port,
+ struct tty_driver *driver, unsigned index,
+ struct device *device, void *drvdata,
+ const struct attribute_group **attr_grp);
+void tty_port_unregister_device(struct tty_port *port,
+ struct tty_driver *driver, unsigned index);
+int tty_port_alloc_xmit_buf(struct tty_port *port);
+void tty_port_free_xmit_buf(struct tty_port *port);
+void tty_port_destroy(struct tty_port *port);
+void tty_port_put(struct tty_port *port);
+
+static inline struct tty_port *tty_port_get(struct tty_port *port)
+{
+ if (port && kref_get_unless_zero(&port->kref))
+ return port;
+ return NULL;
+}
+
+/* If the cts flow control is enabled, return true. */
+static inline bool tty_port_cts_enabled(const struct tty_port *port)
+{
+ return test_bit(TTY_PORT_CTS_FLOW, &port->iflags);
+}
+
+static inline void tty_port_set_cts_flow(struct tty_port *port, bool val)
+{
+ assign_bit(TTY_PORT_CTS_FLOW, &port->iflags, val);
+}
+
+static inline bool tty_port_active(const struct tty_port *port)
+{
+ return test_bit(TTY_PORT_ACTIVE, &port->iflags);
+}
+
+static inline void tty_port_set_active(struct tty_port *port, bool val)
+{
+ assign_bit(TTY_PORT_ACTIVE, &port->iflags, val);
+}
+
+static inline bool tty_port_check_carrier(const struct tty_port *port)
+{
+ return test_bit(TTY_PORT_CHECK_CD, &port->iflags);
+}
+
+static inline void tty_port_set_check_carrier(struct tty_port *port, bool val)
+{
+ assign_bit(TTY_PORT_CHECK_CD, &port->iflags, val);
+}
+
+static inline bool tty_port_suspended(const struct tty_port *port)
+{
+ return test_bit(TTY_PORT_SUSPENDED, &port->iflags);
+}
+
+static inline void tty_port_set_suspended(struct tty_port *port, bool val)
+{
+ assign_bit(TTY_PORT_SUSPENDED, &port->iflags, val);
+}
+
+static inline bool tty_port_initialized(const struct tty_port *port)
+{
+ return test_bit(TTY_PORT_INITIALIZED, &port->iflags);
+}
+
+static inline void tty_port_set_initialized(struct tty_port *port, bool val)
+{
+ assign_bit(TTY_PORT_INITIALIZED, &port->iflags, val);
+}
+
+static inline bool tty_port_kopened(const struct tty_port *port)
+{
+ return test_bit(TTY_PORT_KOPENED, &port->iflags);
+}
+
+static inline void tty_port_set_kopened(struct tty_port *port, bool val)
+{
+ assign_bit(TTY_PORT_KOPENED, &port->iflags, val);
+}
+
+struct tty_struct *tty_port_tty_get(struct tty_port *port);
+void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty);
+int tty_port_carrier_raised(struct tty_port *port);
+void tty_port_raise_dtr_rts(struct tty_port *port);
+void tty_port_lower_dtr_rts(struct tty_port *port);
+void tty_port_hangup(struct tty_port *port);
+void tty_port_tty_hangup(struct tty_port *port, bool check_clocal);
+void tty_port_tty_wakeup(struct tty_port *port);
+int tty_port_block_til_ready(struct tty_port *port, struct tty_struct *tty,
+ struct file *filp);
+int tty_port_close_start(struct tty_port *port, struct tty_struct *tty,
+ struct file *filp);
+void tty_port_close_end(struct tty_port *port, struct tty_struct *tty);
+void tty_port_close(struct tty_port *port, struct tty_struct *tty,
+ struct file *filp);
+int tty_port_install(struct tty_port *port, struct tty_driver *driver,
+ struct tty_struct *tty);
+int tty_port_open(struct tty_port *port, struct tty_struct *tty,
+ struct file *filp);
+
+static inline int tty_port_users(struct tty_port *port)
+{
+ return port->count + port->blocked_open;
+}
+
+#endif
--
2.32.0