From 9cc63f8bcd560c760d0b12e15bba8f81c86237cf Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Fri, 14 Aug 2026 15:43:51 -0700 Subject: Merge branches 'expcb.2026.07.24a', 'misc.2026.07.30a', 'rcu-tasks.2026.07.30a', 'srcu.2026.08.11a' and 'torture.2026.08.14a' into HEAD Changes: Make expedited grace periods expedite normal RCU callbacks Miscellaneous fixes: * Improve diagnostic output with character task states. * Mark accesses to inform KCSAN of concurrency design. * Move from kmalloc() to kmalloc_obj(). * Documentation updates. * Improve handling of RCU deferred quiescent states. * Clean up unused function arguments and structure fields. * Reduce show_rcu_gp_kthreads() stack space. Tasks RCU updates: * Clean up after SRCU re-implementation of Tasks Trace RCU. * Mark accesses to inform KCSAN of concurrency design. * Add ->lazy_timer status to diagnostic output. * Remove an unnecessary memory barrier. * Fix a data race, courtesy of KCSAN. * Documentation updates. * Convert cond_resched_tasks_rcu_qs() from macro to static inline function. SRCU updates: * Add Rust helpers for SRCU. * Avoid losing queued work at cleanup_srcu_struct() time. Torture-test updates: * Preparation work for immediate RCU priority deboosting. * Test RCU readers from real interrupt handlers (as opposed to softirq). * Simplify code through use of cpumask_next_wrap(). * Improve diagnostic output with character task states. * Add rcutorture.nwriters parameter to allow lightweight stall testing, and rcutorture.stall_only to make doing so easier. * Test an RCU Tasks Trace grace period implying an RCU grace period. * Make RCU Tasks Trace torturing track reader batches. * Fix a data race, courtesy of KCSAN. * Plug a shuffle_tmp_mask memory leak on kthread spawn failure. --- drivers/tty/tty.h | 125 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 125 insertions(+) create mode 100644 drivers/tty/tty.h (limited to 'drivers/tty/tty.h') diff --git a/drivers/tty/tty.h b/drivers/tty/tty.h new file mode 100644 index 000000000..93cf5ef1e --- /dev/null +++ b/drivers/tty/tty.h @@ -0,0 +1,125 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * TTY core internal functions + */ + +#ifndef _TTY_INTERNAL_H +#define _TTY_INTERNAL_H + +#define tty_msg(fn, tty, f, ...) \ + fn("%s %s: " f, tty_driver_name(tty), tty_name(tty), ##__VA_ARGS__) + +#define tty_debug(tty, f, ...) tty_msg(pr_debug, tty, f, ##__VA_ARGS__) +#define tty_notice(tty, f, ...) tty_msg(pr_notice, tty, f, ##__VA_ARGS__) +#define tty_warn(tty, f, ...) tty_msg(pr_warn, tty, f, ##__VA_ARGS__) +#define tty_err(tty, f, ...) tty_msg(pr_err, tty, f, ##__VA_ARGS__) + +#define tty_info_ratelimited(tty, f, ...) \ + tty_msg(pr_info_ratelimited, tty, f, ##__VA_ARGS__) + +/* + * Lock subclasses for tty locks + * + * TTY_LOCK_NORMAL is for normal ttys and master ptys. + * TTY_LOCK_SLAVE is for slave ptys only. + * + * Lock subclasses are necessary for handling nested locking with pty pairs. + * tty locks which use nested locking: + * + * legacy_mutex - Nested tty locks are necessary for releasing pty pairs. + * The stable lock order is master pty first, then slave pty. + * termios_rwsem - The stable lock order is tty_buffer lock->termios_rwsem. + * Subclassing this lock enables the slave pty to hold its + * termios_rwsem when claiming the master tty_buffer lock. + * tty_buffer lock - slave ptys can claim nested buffer lock when handling + * signal chars. The stable lock order is slave pty, then + * master. + */ +enum { + TTY_LOCK_NORMAL = 0, + TTY_LOCK_SLAVE, +}; + +/* Values for tty->flow_change */ +enum tty_flow_change { + TTY_FLOW_NO_CHANGE, + TTY_THROTTLE_SAFE, + TTY_UNTHROTTLE_SAFE, +}; + +static inline void __tty_set_flow_change(struct tty_struct *tty, + enum tty_flow_change val) +{ + tty->flow_change = val; +} + +static inline void tty_set_flow_change(struct tty_struct *tty, + enum tty_flow_change val) +{ + tty->flow_change = val; + smp_mb(); +} + +int tty_ldisc_lock(struct tty_struct *tty, unsigned long timeout); +void tty_ldisc_unlock(struct tty_struct *tty); + +int __tty_check_change(struct tty_struct *tty, int sig); +int tty_check_change(struct tty_struct *tty); +void __stop_tty(struct tty_struct *tty); +void __start_tty(struct tty_struct *tty); +void tty_write_unlock(struct tty_struct *tty); +int tty_write_lock(struct tty_struct *tty, bool ndelay); +void tty_vhangup_session(struct tty_struct *tty); +void tty_open_proc_set_tty(struct file *filp, struct tty_struct *tty); +int tty_signal_session_leader(struct tty_struct *tty, int exit_session); +void session_clear_tty(struct pid *session); +void tty_buffer_free_all(struct tty_port *port); +void tty_buffer_flush(struct tty_struct *tty, struct tty_ldisc *ld); +void tty_buffer_init(struct tty_port *port); +void tty_buffer_set_lock_subclass(struct tty_port *port); +bool tty_buffer_restart_work(struct tty_port *port); +bool tty_buffer_cancel_work(struct tty_port *port); +void tty_buffer_flush_work(struct tty_port *port); +speed_t tty_termios_input_baud_rate(const struct ktermios *termios); +void tty_ldisc_hangup(struct tty_struct *tty, bool reset); +int tty_ldisc_reinit(struct tty_struct *tty, int disc); +long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); +long tty_jobctrl_ioctl(struct tty_struct *tty, struct tty_struct *real_tty, + struct file *file, unsigned int cmd, unsigned long arg); +void tty_default_fops(struct file_operations *fops); +struct tty_struct *alloc_tty_struct(struct tty_driver *driver, int idx); +int tty_alloc_file(struct file *file); +void tty_add_file(struct tty_struct *tty, struct file *file); +void tty_free_file(struct file *file); +int tty_release(struct inode *inode, struct file *filp); + +#define tty_is_writelocked(tty) (mutex_is_locked(&tty->atomic_write_lock)) + +int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty); +void tty_ldisc_release(struct tty_struct *tty); +int __must_check tty_ldisc_init(struct tty_struct *tty); +void tty_ldisc_deinit(struct tty_struct *tty); + +extern int tty_ldisc_autoload; + +/* tty_audit.c */ +#ifdef CONFIG_AUDIT +void tty_audit_add_data(const struct tty_struct *tty, const void *data, + size_t size); +void tty_audit_tiocsti(const struct tty_struct *tty, u8 ch); +#else +static inline void tty_audit_add_data(const struct tty_struct *tty, + const void *data, size_t size) +{ +} +static inline void tty_audit_tiocsti(const struct tty_struct *tty, u8 ch) +{ +} +#endif + +ssize_t redirected_tty_write(struct kiocb *, struct iov_iter *); + +int tty_insert_flip_string_and_push_buffer(struct tty_port *port, + const u8 *chars, size_t cnt); + +#endif -- cgit v1.3.1