8977d929e4
Prevent stalled processing of received data when a driver allocates tty buffer space but does not immediately follow the allocation with more data and a call to schedule receive tty processing. (example: hvc_console) This bug was introduced by the first locking patch for the new tty buffering. Signed-off-by: Paul Fulghum <paulkf@microgate.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
50 lines
1.3 KiB
C
50 lines
1.3 KiB
C
#ifndef _LINUX_TTY_FLIP_H
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#define _LINUX_TTY_FLIP_H
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extern int tty_buffer_request_room(struct tty_struct *tty, size_t size);
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extern int tty_insert_flip_string(struct tty_struct *tty, unsigned char *chars, size_t size);
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extern int tty_insert_flip_string_flags(struct tty_struct *tty, unsigned char *chars, char *flags, size_t size);
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extern int tty_prepare_flip_string(struct tty_struct *tty, unsigned char **chars, size_t size);
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extern int tty_prepare_flip_string_flags(struct tty_struct *tty, unsigned char **chars, char **flags, size_t size);
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#ifdef INCLUDE_INLINE_FUNCS
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#define _INLINE_ extern
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#else
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#define _INLINE_ static __inline__
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#endif
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_INLINE_ int tty_insert_flip_char(struct tty_struct *tty,
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unsigned char ch, char flag)
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{
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struct tty_buffer *tb = tty->buf.tail;
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if (tb && tb->active && tb->used < tb->size) {
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tb->flag_buf_ptr[tb->used] = flag;
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tb->char_buf_ptr[tb->used++] = ch;
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return 1;
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}
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return tty_insert_flip_string_flags(tty, &ch, &flag, 1);
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}
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_INLINE_ void tty_schedule_flip(struct tty_struct *tty)
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{
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unsigned long flags;
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spin_lock_irqsave(&tty->buf.lock, flags);
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if (tty->buf.tail != NULL) {
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tty->buf.tail->active = 0;
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tty->buf.tail->commit = tty->buf.tail->used;
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}
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spin_unlock_irqrestore(&tty->buf.lock, flags);
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schedule_delayed_work(&tty->buf.work, 1);
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}
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#undef _INLINE_
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#endif /* _LINUX_TTY_FLIP_H */
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