Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 518 insertions, 0 deletions

diff --git a/include/linux/tty.h b/include/linux/tty.h
new file mode 100644
index 000000000..f002d0f25
--- /dev/null
+++ b/include/linux/tty.h
@@ -0,0 +1,518 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_TTY_H
+#define _LINUX_TTY_H
+
+#include <linux/fs.h>
+#include <linux/major.h>
+#include <linux/termios.h>
+#include <linux/workqueue.h>
+#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>
+#include <linux/rwsem.h>
+#include <linux/llist.h>
+
+
+/*
+ * (Note: the *_driver.minor_start values 1, 64, 128, 192 are
+ * hardcoded at present.)
+ */
+#define NR_UNIX98_PTY_DEFAULT	4096      /* Default maximum for Unix98 ptys */
+#define NR_UNIX98_PTY_RESERVE	1024	  /* Default reserve for main devpts */
+#define NR_UNIX98_PTY_MAX	(1 << MINORBITS) /* Absolute limit */
+
+/*
+ * This character is the same as _POSIX_VDISABLE: it cannot be used as
+ * a c_cc[] character, but indicates that a particular special character
+ * isn't in use (eg VINTR has no character etc)
+ */
+#define __DISABLED_CHAR '\0'
+
+#define INTR_CHAR(tty) ((tty)->termios.c_cc[VINTR])
+#define QUIT_CHAR(tty) ((tty)->termios.c_cc[VQUIT])
+#define ERASE_CHAR(tty) ((tty)->termios.c_cc[VERASE])
+#define KILL_CHAR(tty) ((tty)->termios.c_cc[VKILL])
+#define EOF_CHAR(tty) ((tty)->termios.c_cc[VEOF])
+#define TIME_CHAR(tty) ((tty)->termios.c_cc[VTIME])
+#define MIN_CHAR(tty) ((tty)->termios.c_cc[VMIN])
+#define SWTC_CHAR(tty) ((tty)->termios.c_cc[VSWTC])
+#define START_CHAR(tty) ((tty)->termios.c_cc[VSTART])
+#define STOP_CHAR(tty) ((tty)->termios.c_cc[VSTOP])
+#define SUSP_CHAR(tty) ((tty)->termios.c_cc[VSUSP])
+#define EOL_CHAR(tty) ((tty)->termios.c_cc[VEOL])
+#define REPRINT_CHAR(tty) ((tty)->termios.c_cc[VREPRINT])
+#define DISCARD_CHAR(tty) ((tty)->termios.c_cc[VDISCARD])
+#define WERASE_CHAR(tty) ((tty)->termios.c_cc[VWERASE])
+#define LNEXT_CHAR(tty)	((tty)->termios.c_cc[VLNEXT])
+#define EOL2_CHAR(tty) ((tty)->termios.c_cc[VEOL2])
+
+#define _I_FLAG(tty, f)	((tty)->termios.c_iflag & (f))
+#define _O_FLAG(tty, f)	((tty)->termios.c_oflag & (f))
+#define _C_FLAG(tty, f)	((tty)->termios.c_cflag & (f))
+#define _L_FLAG(tty, f)	((tty)->termios.c_lflag & (f))
+
+#define I_IGNBRK(tty)	_I_FLAG((tty), IGNBRK)
+#define I_BRKINT(tty)	_I_FLAG((tty), BRKINT)
+#define I_IGNPAR(tty)	_I_FLAG((tty), IGNPAR)
+#define I_PARMRK(tty)	_I_FLAG((tty), PARMRK)
+#define I_INPCK(tty)	_I_FLAG((tty), INPCK)
+#define I_ISTRIP(tty)	_I_FLAG((tty), ISTRIP)
+#define I_INLCR(tty)	_I_FLAG((tty), INLCR)
+#define I_IGNCR(tty)	_I_FLAG((tty), IGNCR)
+#define I_ICRNL(tty)	_I_FLAG((tty), ICRNL)
+#define I_IUCLC(tty)	_I_FLAG((tty), IUCLC)
+#define I_IXON(tty)	_I_FLAG((tty), IXON)
+#define I_IXANY(tty)	_I_FLAG((tty), IXANY)
+#define I_IXOFF(tty)	_I_FLAG((tty), IXOFF)
+#define I_IMAXBEL(tty)	_I_FLAG((tty), IMAXBEL)
+#define I_IUTF8(tty)	_I_FLAG((tty), IUTF8)
+
+#define O_OPOST(tty)	_O_FLAG((tty), OPOST)
+#define O_OLCUC(tty)	_O_FLAG((tty), OLCUC)
+#define O_ONLCR(tty)	_O_FLAG((tty), ONLCR)
+#define O_OCRNL(tty)	_O_FLAG((tty), OCRNL)
+#define O_ONOCR(tty)	_O_FLAG((tty), ONOCR)
+#define O_ONLRET(tty)	_O_FLAG((tty), ONLRET)
+#define O_OFILL(tty)	_O_FLAG((tty), OFILL)
+#define O_OFDEL(tty)	_O_FLAG((tty), OFDEL)
+#define O_NLDLY(tty)	_O_FLAG((tty), NLDLY)
+#define O_CRDLY(tty)	_O_FLAG((tty), CRDLY)
+#define O_TABDLY(tty)	_O_FLAG((tty), TABDLY)
+#define O_BSDLY(tty)	_O_FLAG((tty), BSDLY)
+#define O_VTDLY(tty)	_O_FLAG((tty), VTDLY)
+#define O_FFDLY(tty)	_O_FLAG((tty), FFDLY)
+
+#define C_BAUD(tty)	_C_FLAG((tty), CBAUD)
+#define C_CSIZE(tty)	_C_FLAG((tty), CSIZE)
+#define C_CSTOPB(tty)	_C_FLAG((tty), CSTOPB)
+#define C_CREAD(tty)	_C_FLAG((tty), CREAD)
+#define C_PARENB(tty)	_C_FLAG((tty), PARENB)
+#define C_PARODD(tty)	_C_FLAG((tty), PARODD)
+#define C_HUPCL(tty)	_C_FLAG((tty), HUPCL)
+#define C_CLOCAL(tty)	_C_FLAG((tty), CLOCAL)
+#define C_CIBAUD(tty)	_C_FLAG((tty), CIBAUD)
+#define C_CRTSCTS(tty)	_C_FLAG((tty), CRTSCTS)
+#define C_CMSPAR(tty)	_C_FLAG((tty), CMSPAR)
+
+#define L_ISIG(tty)	_L_FLAG((tty), ISIG)
+#define L_ICANON(tty)	_L_FLAG((tty), ICANON)
+#define L_XCASE(tty)	_L_FLAG((tty), XCASE)
+#define L_ECHO(tty)	_L_FLAG((tty), ECHO)
+#define L_ECHOE(tty)	_L_FLAG((tty), ECHOE)
+#define L_ECHOK(tty)	_L_FLAG((tty), ECHOK)
+#define L_ECHONL(tty)	_L_FLAG((tty), ECHONL)
+#define L_NOFLSH(tty)	_L_FLAG((tty), NOFLSH)
+#define L_TOSTOP(tty)	_L_FLAG((tty), TOSTOP)
+#define L_ECHOCTL(tty)	_L_FLAG((tty), ECHOCTL)
+#define L_ECHOPRT(tty)	_L_FLAG((tty), ECHOPRT)
+#define L_ECHOKE(tty)	_L_FLAG((tty), ECHOKE)
+#define L_FLUSHO(tty)	_L_FLAG((tty), FLUSHO)
+#define L_PENDIN(tty)	_L_FLAG((tty), PENDIN)
+#define L_IEXTEN(tty)	_L_FLAG((tty), IEXTEN)
+#define L_EXTPROC(tty)	_L_FLAG((tty), EXTPROC)
+
+struct device;
+struct signal_struct;
+struct tty_operations;
+
+/**
+ * struct tty_struct - state associated with a tty while open
+ *
+ * @kref: reference counting by tty_kref_get() and tty_kref_put(), reaching zero
+ *	  frees the structure
+ * @dev: class device or %NULL (e.g. ptys, serdev)
+ * @driver: &struct tty_driver operating this tty
+ * @ops: &struct tty_operations of @driver for this tty (open, close, etc.)
+ * @index: index of this tty (e.g. to construct @name like tty12)
+ * @ldisc_sem: protects line discipline changes (@ldisc) -- lock tty not pty
+ * @ldisc: the current line discipline for this tty (n_tty by default)
+ * @atomic_write_lock: protects against concurrent writers, i.e. locks
+ *		       @write_cnt, @write_buf and similar
+ * @legacy_mutex: leftover from history (BKL -> BTM -> @legacy_mutex),
+ *		  protecting several operations on this tty
+ * @throttle_mutex: protects against concurrent tty_throttle_safe() and
+ *		    tty_unthrottle_safe() (but not tty_unthrottle())
+ * @termios_rwsem: protects @termios and @termios_locked
+ * @winsize_mutex: protects @winsize
+ * @termios: termios for the current tty, copied from/to @driver.termios
+ * @termios_locked: locked termios (by %TIOCGLCKTRMIOS and %TIOCSLCKTRMIOS
+ *		    ioctls)
+ * @name: name of the tty constructed by tty_line_name() (e.g. ttyS3)
+ * @flags: bitwise OR of %TTY_THROTTLED, %TTY_IO_ERROR, ...
+ * @count: count of open processes, reaching zero cancels all the work for
+ *	   this tty and drops a @kref too (but does not free this tty)
+ * @winsize: size of the terminal "window" (cf. @winsize_mutex)
+ * @flow: flow settings grouped together, see also @flow.unused
+ * @flow.lock: lock for @flow members
+ * @flow.stopped: tty stopped/started by stop_tty()/start_tty()
+ * @flow.tco_stopped: tty stopped/started by %TCOOFF/%TCOON ioctls (it has
+ *		      precedence over @flow.stopped)
+ * @flow.unused: alignment for Alpha, so that no members other than @flow.* are
+ *		 modified by the same 64b word store. The @flow's __aligned is
+ *		 there for the very same reason.
+ * @ctrl: control settings grouped together, see also @ctrl.unused
+ * @ctrl.lock: lock for @ctrl members
+ * @ctrl.pgrp: process group of this tty (setpgrp(2))
+ * @ctrl.session: session of this tty (setsid(2)). Writes are protected by both
+ *		  @ctrl.lock and @legacy_mutex, readers must use at least one of
+ *		  them.
+ * @ctrl.pktstatus: packet mode status (bitwise OR of %TIOCPKT_ constants)
+ * @ctrl.packet: packet mode enabled
+ * @ctrl.unused: alignment for Alpha, see @flow.unused for explanation
+ * @hw_stopped: not controlled by the tty layer, under @driver's control for CTS
+ *		handling
+ * @receive_room: bytes permitted to feed to @ldisc without any being lost
+ * @flow_change: controls behavior of throttling, see tty_throttle_safe() and
+ *		 tty_unthrottle_safe()
+ * @link: link to another pty (master -> slave and vice versa)
+ * @fasync: state for %O_ASYNC (for %SIGIO); managed by fasync_helper()
+ * @write_wait: concurrent writers are waiting in this queue until they are
+ *		allowed to write
+ * @read_wait: readers wait for data in this queue
+ * @hangup_work: normally a work to perform a hangup (do_tty_hangup()); while
+ *		 freeing the tty, (re)used to release_one_tty()
+ * @disc_data: pointer to @ldisc's private data (e.g. to &struct n_tty_data)
+ * @driver_data: pointer to @driver's private data (e.g. &struct uart_state)
+ * @files_lock:	protects @tty_files list
+ * @tty_files: list of (re)openers of this tty (i.e. linked &struct
+ *	       tty_file_private)
+ * @closing: when set during close, n_tty processes only START & STOP chars
+ * @write_buf: temporary buffer used during tty_write() to copy user data to
+ * @write_cnt: count of bytes written in tty_write() to @write_buf
+ * @SAK_work: if the tty has a pending do_SAK, it is queued here
+ * @port: persistent storage for this device (i.e. &struct tty_port)
+ *
+ * All of the state associated with a tty while the tty is open. Persistent
+ * storage for tty devices is referenced here as @port and is documented in
+ * &struct tty_port.
+ */
+struct tty_struct {
+	struct kref kref;
+	int index;
+	struct device *dev;
+	struct tty_driver *driver;
+	struct tty_port *port;
+	const struct tty_operations *ops;
+
+	struct tty_ldisc *ldisc;
+	struct ld_semaphore ldisc_sem;
+
+	struct mutex atomic_write_lock;
+	struct mutex legacy_mutex;
+	struct mutex throttle_mutex;
+	struct rw_semaphore termios_rwsem;
+	struct mutex winsize_mutex;
+	struct ktermios termios, termios_locked;
+	char name[64];
+	unsigned long flags;
+	int count;
+	unsigned int receive_room;
+	struct winsize winsize;
+
+	struct {
+		spinlock_t lock;
+		bool stopped;
+		bool tco_stopped;
+		unsigned long unused[0];
+	} __aligned(sizeof(unsigned long)) flow;
+
+	struct {
+		struct pid *pgrp;
+		struct pid *session;
+		spinlock_t lock;
+		unsigned char pktstatus;
+		bool packet;
+		unsigned long unused[0];
+	} __aligned(sizeof(unsigned long)) ctrl;
+
+	bool hw_stopped;
+	bool closing;
+	int flow_change;
+
+	struct tty_struct *link;
+	struct fasync_struct *fasync;
+	wait_queue_head_t write_wait;
+	wait_queue_head_t read_wait;
+	struct work_struct hangup_work;
+	void *disc_data;
+	void *driver_data;
+	spinlock_t files_lock;
+	int write_cnt;
+	unsigned char *write_buf;
+
+	struct list_head tty_files;
+
+#define N_TTY_BUF_SIZE 4096
+	struct work_struct SAK_work;
+} __randomize_layout;
+
+/* Each of a tty's open files has private_data pointing to tty_file_private */
+struct tty_file_private {
+	struct tty_struct *tty;
+	struct file *file;
+	struct list_head list;
+};
+
+/**
+ * DOC: TTY Struct Flags
+ *
+ * These bits are used in the :c:member:`tty_struct.flags` field.
+ *
+ * So that interrupts won't be able to mess up the queues,
+ * copy_to_cooked must be atomic with respect to itself, as must
+ * tty->write.  Thus, you must use the inline functions set_bit() and
+ * clear_bit() to make things atomic.
+ *
+ * TTY_THROTTLED
+ *	Driver input is throttled. The ldisc should call
+ *	:c:member:`tty_driver.unthrottle()` in order to resume reception when
+ *	it is ready to process more data (at threshold min).
+ *
+ * TTY_IO_ERROR
+ *	If set, causes all subsequent userspace read/write calls on the tty to
+ *	fail, returning -%EIO. (May be no ldisc too.)
+ *
+ * TTY_OTHER_CLOSED
+ *	Device is a pty and the other side has closed.
+ *
+ * TTY_EXCLUSIVE
+ *	Exclusive open mode (a single opener).
+ *
+ * TTY_DO_WRITE_WAKEUP
+ *	If set, causes the driver to call the
+ *	:c:member:`tty_ldisc_ops.write_wakeup()` method in order to resume
+ *	transmission when it can accept more data to transmit.
+ *
+ * TTY_LDISC_OPEN
+ *	Indicates that a line discipline is open. For debugging purposes only.
+ *
+ * TTY_PTY_LOCK
+ *	A flag private to pty code to implement %TIOCSPTLCK/%TIOCGPTLCK logic.
+ *
+ * TTY_NO_WRITE_SPLIT
+ *	Prevent driver from splitting up writes into smaller chunks (preserve
+ *	write boundaries to driver).
+ *
+ * TTY_HUPPED
+ *	The TTY was hung up. This is set post :c:member:`tty_driver.hangup()`.
+ *
+ * TTY_HUPPING
+ *	The TTY is in the process of hanging up to abort potential readers.
+ *
+ * TTY_LDISC_CHANGING
+ *	Line discipline for this TTY is being changed. I/O should not block
+ *	when this is set. Use tty_io_nonblock() to check.
+ *
+ * TTY_LDISC_HALTED
+ *	Line discipline for this TTY was stopped. No work should be queued to
+ *	this ldisc.
+ */
+#define TTY_THROTTLED		0
+#define TTY_IO_ERROR		1
+#define TTY_OTHER_CLOSED	2
+#define TTY_EXCLUSIVE		3
+#define TTY_DO_WRITE_WAKEUP	5
+#define TTY_LDISC_OPEN		11
+#define TTY_PTY_LOCK		16
+#define TTY_NO_WRITE_SPLIT	17
+#define TTY_HUPPED		18
+#define TTY_HUPPING		19
+#define TTY_LDISC_CHANGING	20
+#define TTY_LDISC_HALTED	22
+
+static inline bool tty_io_nonblock(struct tty_struct *tty, struct file *file)
+{
+	return file->f_flags & O_NONBLOCK ||
+		test_bit(TTY_LDISC_CHANGING, &tty->flags);
+}
+
+static inline bool tty_io_error(struct tty_struct *tty)
+{
+	return test_bit(TTY_IO_ERROR, &tty->flags);
+}
+
+static inline bool tty_throttled(struct tty_struct *tty)
+{
+	return test_bit(TTY_THROTTLED, &tty->flags);
+}
+
+#ifdef CONFIG_TTY
+void tty_kref_put(struct tty_struct *tty);
+struct pid *tty_get_pgrp(struct tty_struct *tty);
+void tty_vhangup_self(void);
+void disassociate_ctty(int priv);
+dev_t tty_devnum(struct tty_struct *tty);
+void proc_clear_tty(struct task_struct *p);
+struct tty_struct *get_current_tty(void);
+/* tty_io.c */
+int __init tty_init(void);
+const char *tty_name(const struct tty_struct *tty);
+struct tty_struct *tty_kopen_exclusive(dev_t device);
+struct tty_struct *tty_kopen_shared(dev_t device);
+void tty_kclose(struct tty_struct *tty);
+int tty_dev_name_to_number(const char *name, dev_t *number);
+#else
+static inline void tty_kref_put(struct tty_struct *tty)
+{ }
+static inline struct pid *tty_get_pgrp(struct tty_struct *tty)
+{ return NULL; }
+static inline void tty_vhangup_self(void)
+{ }
+static inline void disassociate_ctty(int priv)
+{ }
+static inline dev_t tty_devnum(struct tty_struct *tty)
+{ return 0; }
+static inline void proc_clear_tty(struct task_struct *p)
+{ }
+static inline struct tty_struct *get_current_tty(void)
+{ return NULL; }
+/* tty_io.c */
+static inline int __init tty_init(void)
+{ return 0; }
+static inline const char *tty_name(const struct tty_struct *tty)
+{ return "(none)"; }
+static inline struct tty_struct *tty_kopen_exclusive(dev_t device)
+{ return ERR_PTR(-ENODEV); }
+static inline void tty_kclose(struct tty_struct *tty)
+{ }
+static inline int tty_dev_name_to_number(const char *name, dev_t *number)
+{ return -ENOTSUPP; }
+#endif
+
+extern struct ktermios tty_std_termios;
+
+int vcs_init(void);
+
+extern const struct class tty_class;
+
+/**
+ *	tty_kref_get		-	get a tty reference
+ *	@tty: tty device
+ *
+ *	Return a new reference to a tty object. The caller must hold
+ *	sufficient locks/counts to ensure that their existing reference cannot
+ *	go away
+ */
+
+static inline struct tty_struct *tty_kref_get(struct tty_struct *tty)
+{
+	if (tty)
+		kref_get(&tty->kref);
+	return tty;
+}
+
+const char *tty_driver_name(const struct tty_struct *tty);
+void tty_wait_until_sent(struct tty_struct *tty, long timeout);
+void stop_tty(struct tty_struct *tty);
+void start_tty(struct tty_struct *tty);
+void tty_write_message(struct tty_struct *tty, char *msg);
+int tty_send_xchar(struct tty_struct *tty, char ch);
+int tty_put_char(struct tty_struct *tty, unsigned char c);
+unsigned int tty_chars_in_buffer(struct tty_struct *tty);
+unsigned int tty_write_room(struct tty_struct *tty);
+void tty_driver_flush_buffer(struct tty_struct *tty);
+void tty_unthrottle(struct tty_struct *tty);
+int tty_throttle_safe(struct tty_struct *tty);
+int tty_unthrottle_safe(struct tty_struct *tty);
+int tty_do_resize(struct tty_struct *tty, struct winsize *ws);
+int tty_get_icount(struct tty_struct *tty,
+		struct serial_icounter_struct *icount);
+int is_current_pgrp_orphaned(void);
+void tty_hangup(struct tty_struct *tty);
+void tty_vhangup(struct tty_struct *tty);
+int tty_hung_up_p(struct file *filp);
+void do_SAK(struct tty_struct *tty);
+void __do_SAK(struct tty_struct *tty);
+void no_tty(void);
+speed_t tty_termios_baud_rate(const struct ktermios *termios);
+void tty_termios_encode_baud_rate(struct ktermios *termios, speed_t ibaud,
+		speed_t obaud);
+void tty_encode_baud_rate(struct tty_struct *tty, speed_t ibaud,
+		speed_t obaud);
+
+/**
+ *	tty_get_baud_rate	-	get tty bit rates
+ *	@tty: tty to query
+ *
+ *	Returns the baud rate as an integer for this terminal. The
+ *	termios lock must be held by the caller and the terminal bit
+ *	flags may be updated.
+ *
+ *	Locking: none
+ */
+static inline speed_t tty_get_baud_rate(struct tty_struct *tty)
+{
+	return tty_termios_baud_rate(&tty->termios);
+}
+
+unsigned char tty_get_char_size(unsigned int cflag);
+unsigned char tty_get_frame_size(unsigned int cflag);
+
+void tty_termios_copy_hw(struct ktermios *new, const struct ktermios *old);
+bool tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b);
+int tty_set_termios(struct tty_struct *tty, struct ktermios *kt);
+
+void tty_wakeup(struct tty_struct *tty);
+
+int tty_mode_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg);
+int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
+struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx);
+void tty_release_struct(struct tty_struct *tty, int idx);
+void tty_init_termios(struct tty_struct *tty);
+void tty_save_termios(struct tty_struct *tty);
+int tty_standard_install(struct tty_driver *driver,
+		struct tty_struct *tty);
+
+extern struct mutex tty_mutex;
+
+/* n_tty.c */
+void n_tty_inherit_ops(struct tty_ldisc_ops *ops);
+#ifdef CONFIG_TTY
+void __init n_tty_init(void);
+#else
+static inline void n_tty_init(void) { }
+#endif
+
+/* tty_audit.c */
+#ifdef CONFIG_AUDIT
+void tty_audit_exit(void);
+void tty_audit_fork(struct signal_struct *sig);
+int tty_audit_push(void);
+#else
+static inline void tty_audit_exit(void)
+{
+}
+static inline void tty_audit_fork(struct signal_struct *sig)
+{
+}
+static inline int tty_audit_push(void)
+{
+	return 0;
+}
+#endif
+
+/* tty_ioctl.c */
+int n_tty_ioctl_helper(struct tty_struct *tty, unsigned int cmd,
+		unsigned long arg);
+
+/* vt.c */
+
+int vt_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg);
+
+long vt_compat_ioctl(struct tty_struct *tty, unsigned int cmd,
+		unsigned long arg);
+
+/* tty_mutex.c */
+/* functions for preparation of BKL removal */
+void tty_lock(struct tty_struct *tty);
+int  tty_lock_interruptible(struct tty_struct *tty);
+void tty_unlock(struct tty_struct *tty);
+void tty_lock_slave(struct tty_struct *tty);
+void tty_unlock_slave(struct tty_struct *tty);
+void tty_set_lock_subclass(struct tty_struct *tty);
+
+#endif