diff options
Diffstat (limited to 'include/linux/tty.h')
| -rw-r--r-- | include/linux/tty.h | 66 |
1 files changed, 39 insertions, 27 deletions
diff --git a/include/linux/tty.h b/include/linux/tty.h index 01ac30efd6a6..64f864651d86 100644 --- a/include/linux/tty.h +++ b/include/linux/tty.h @@ -10,6 +10,8 @@ #include <linux/mutex.h> #include <linux/tty_flags.h> #include <uapi/linux/tty.h> +#include <linux/rwsem.h> +#include <linux/llist.h> @@ -29,9 +31,10 @@ #define __DISABLED_CHAR '\0' struct tty_buffer { - struct tty_buffer *next; - char *char_buf_ptr; - unsigned char *flag_buf_ptr; + union { + struct tty_buffer *next; + struct llist_node free; + }; int used; int size; int commit; @@ -40,25 +43,25 @@ struct tty_buffer { unsigned long data[0]; }; -/* - * We default to dicing tty buffer allocations to this many characters - * in order to avoid multiple page allocations. We know the size of - * tty_buffer itself but it must also be taken into account that the - * the buffer is 256 byte aligned. See tty_buffer_find for the allocation - * logic this must match - */ - -#define TTY_BUFFER_PAGE (((PAGE_SIZE - sizeof(struct tty_buffer)) / 2) & ~0xFF) +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 work_struct work; - spinlock_t lock; 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 memory_used; /* In-use buffers excluding free list */ struct tty_buffer *tail; /* Active buffer */ - struct tty_buffer *free; /* Free queue head */ - int memory_used; /* Buffer space used excluding - free queue */ }; /* * When a break, frame error, or parity error happens, these codes are @@ -199,9 +202,6 @@ struct tty_port { wait_queue_head_t close_wait; /* Close waiters */ wait_queue_head_t delta_msr_wait; /* Modem status change */ unsigned long flags; /* TTY flags ASY_*/ - unsigned long iflags; /* TTYP_ internal flags */ -#define TTYP_FLUSHING 1 /* Flushing to ldisc in progress */ -#define TTYP_FLUSHPENDING 2 /* Queued buffer flush pending */ unsigned char console:1, /* port is a console */ low_latency:1; /* direct buffer flush */ struct mutex mutex; /* Locking */ @@ -238,14 +238,16 @@ struct tty_struct { int index; /* Protects ldisc changes: Lock tty not pty */ - struct mutex ldisc_mutex; + struct ld_semaphore ldisc_sem; struct tty_ldisc *ldisc; struct mutex atomic_write_lock; struct mutex legacy_mutex; - struct mutex termios_mutex; + struct mutex throttle_mutex; + struct rw_semaphore termios_rwsem; + struct mutex winsize_mutex; spinlock_t ctrl_lock; - /* Termios values are protected by the termios mutex */ + /* Termios values are protected by the termios rwsem */ struct ktermios termios, termios_locked; struct termiox *termiox; /* May be NULL for unsupported */ char name[64]; @@ -253,7 +255,7 @@ struct tty_struct { struct pid *session; unsigned long flags; int count; - struct winsize winsize; /* termios mutex */ + struct winsize winsize; /* winsize_mutex */ unsigned char stopped:1, hw_stopped:1, flow_stopped:1, packet:1; unsigned char ctrl_status; /* ctrl_lock */ unsigned int receive_room; /* Bytes free for queue */ @@ -303,10 +305,7 @@ struct tty_file_private { #define TTY_EXCLUSIVE 3 /* Exclusive open mode */ #define TTY_DEBUG 4 /* Debugging */ #define TTY_DO_WRITE_WAKEUP 5 /* Call write_wakeup after queuing new */ -#define TTY_PUSH 6 /* n_tty private */ #define TTY_CLOSING 7 /* ->close() in progress */ -#define TTY_LDISC 9 /* Line discipline attached */ -#define TTY_LDISC_CHANGING 10 /* Line discipline changing */ #define TTY_LDISC_OPEN 11 /* Line discipline is open */ #define TTY_PTY_LOCK 16 /* pty private */ #define TTY_NO_WRITE_SPLIT 17 /* Preserve write boundaries to driver */ @@ -559,6 +558,19 @@ extern void tty_ldisc_init(struct tty_struct *tty); extern void tty_ldisc_deinit(struct tty_struct *tty); extern void tty_ldisc_begin(void); +static inline int tty_ldisc_receive_buf(struct tty_ldisc *ld, unsigned char *p, + char *f, int count) +{ + if (ld->ops->receive_buf2) + count = ld->ops->receive_buf2(ld->tty, p, f, count); + else { + count = min_t(int, count, ld->tty->receive_room); + if (count) + ld->ops->receive_buf(ld->tty, p, f, count); + } + return count; +} + /* n_tty.c */ extern struct tty_ldisc_ops tty_ldisc_N_TTY; |