From 8d29e0024437ae9184ae24f817ef0fda80b8cd3c Mon Sep 17 00:00:00 2001 From: Jiri Slaby Date: Fri, 23 Jul 2021 12:31:45 +0200 Subject: tty: move tty_buffer definitions to new tty_buffer.h tty.h is large enough currently. And I am slowly adding kernel-doc documentation, so it grows to unmaintainable long mess. To avoid this, split tty.h further into tty_buffer.h and move there tty_buffer-related declarations and function prototypes. Note that many of the tty_buffer.c function prototypes reside now in tty_flip.h. But we cannot move struct tty_buffer & friends because: * tty_insert_flip_char() in tty_flip.h needs both struct tty_port and struct tty_buffer defined. * struct tty_port in tty_port.h needs struct tty_buffer defined. So if we moved struct tty_buffer to tty_flip.h too, tty_flip.h would need tty_port.h and that would need tty_flip.h (to have tty_buffer) again. Hence we introduce new header tty_buffer.h here to break this circular dependency. Signed-off-by: Jiri Slaby Link: https://lore.kernel.org/r/20210723103147.18250-7-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman --- include/linux/tty_buffer.h | 59 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 59 insertions(+) create mode 100644 include/linux/tty_buffer.h (limited to 'include/linux/tty_buffer.h') diff --git a/include/linux/tty_buffer.h b/include/linux/tty_buffer.h new file mode 100644 index 000000000000..3b9d77604291 --- /dev/null +++ b/include/linux/tty_buffer.h @@ -0,0 +1,59 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _LINUX_TTY_BUFFER_H +#define _LINUX_TTY_BUFFER_H + +#include +#include +#include +#include + +struct tty_buffer { + union { + struct tty_buffer *next; + struct llist_node free; + }; + int used; + int size; + int commit; + int read; + int flags; + /* Data points here */ + unsigned long data[]; +}; + +/* Values for .flags field of tty_buffer */ +#define TTYB_NORMAL 1 /* buffer has no flags buffer */ + +static inline unsigned char *char_buf_ptr(struct tty_buffer *b, int ofs) +{ + return ((unsigned char *)b->data) + ofs; +} + +static inline char *flag_buf_ptr(struct tty_buffer *b, int ofs) +{ + return (char *)char_buf_ptr(b, ofs) + b->size; +} + +struct tty_bufhead { + struct tty_buffer *head; /* Queue head */ + struct work_struct work; + struct mutex lock; + atomic_t priority; + struct tty_buffer sentinel; + struct llist_head free; /* Free queue head */ + atomic_t mem_used; /* In-use buffers excluding free list */ + int mem_limit; + struct tty_buffer *tail; /* Active buffer */ +}; + +/* + * When a break, frame error, or parity error happens, these codes are + * stuffed into the flags buffer. + */ +#define TTY_NORMAL 0 +#define TTY_BREAK 1 +#define TTY_FRAME 2 +#define TTY_PARITY 3 +#define TTY_OVERRUN 4 + +#endif -- cgit v1.2.3