[linux-block.git] / include / linux / tty_buffer.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_TTY_BUFFER_H
#define _LINUX_TTY_BUFFER_H

#include <linux/atomic.h>
#include <linux/llist.h>
#include <linux/mutex.h>
#include <linux/workqueue.h>

struct tty_buffer {
	union {
		struct tty_buffer *next;
		struct llist_node free;
	};
	int used;
	int size;
	int commit;
	int lookahead;		/* Lazy update on recv, can become less than "read" */
	int read;
	bool flags;
	/* Data points here */
	unsigned long data[];
};

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
Commit	Line	Data
8d29e002 JS	1	/* SPDX-License-Identifier: GPL-2.0 */
	2	#ifndef _LINUX_TTY_BUFFER_H
	3	#define _LINUX_TTY_BUFFER_H
	4
	5	#include <linux/atomic.h>
	6	#include <linux/llist.h>
	7	#include <linux/mutex.h>
	8	#include <linux/workqueue.h>
	9
	10	struct tty_buffer {
	11	union {
	12	struct tty_buffer *next;
	13	struct llist_node free;
	14	};
	15	int used;
	16	int size;
	17	int commit;
6bb6fa69	18	int lookahead; /* Lazy update on recv, can become less than "read" */
8d29e002	19	int read;
2e2b4b89	20	bool flags;
8d29e002 JS	21	/* Data points here */
	22	unsigned long data[];
	23	};
	24
8d29e002 JS	25	static inline unsigned char char_buf_ptr(struct tty_buffer b, int ofs)
	26	{
	27	return ((unsigned char *)b->data) + ofs;
	28	}
	29
	30	static inline char flag_buf_ptr(struct tty_buffer b, int ofs)
	31	{
	32	return (char *)char_buf_ptr(b, ofs) + b->size;
	33	}
	34
	35	struct tty_bufhead {
	36	struct tty_buffer head; / Queue head */
	37	struct work_struct work;
	38	struct mutex lock;
	39	atomic_t priority;
	40	struct tty_buffer sentinel;
	41	struct llist_head free; /* Free queue head */
	42	atomic_t mem_used; /* In-use buffers excluding free list */
	43	int mem_limit;
	44	struct tty_buffer tail; / Active buffer */
	45	};
	46
	47	/*
	48	* When a break, frame error, or parity error happens, these codes are
	49	* stuffed into the flags buffer.
	50	*/
	51	#define TTY_NORMAL 0
	52	#define TTY_BREAK 1
	53	#define TTY_FRAME 2
	54	#define TTY_PARITY 3
	55	#define TTY_OVERRUN 4
	56
	57	#endif