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git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
tty: n_tty: extract n_tty_continue_cookie() from n_tty_read()
n_tty_read() is a very long function doing too much of different stuff.
Extract the "cookie" (continuation read) handling to a separate
function: n_tty_continue_cookie().
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20250317070046.24386-10-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
authored by
Jiri Slaby (SUSE)
and committed by
Greg Kroah-Hartman
aa1ebc9c
67e781f5
+36
-30
+36
-30
drivers/tty/n_tty.c
+36
-30
drivers/tty/n_tty.c
···
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return __tty_check_change(tty, SIGTTIN);
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}
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+
/*
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* We still hold the atomic_read_lock and the termios_rwsem, and can just
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* continue to copy data.
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*/
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static ssize_t n_tty_continue_cookie(struct tty_struct *tty, u8 *kbuf,
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size_t nr, void **cookie)
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{
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struct n_tty_data *ldata = tty->disc_data;
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u8 *kb = kbuf;
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+
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if (ldata->icanon && !L_EXTPROC(tty)) {
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/*
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* If we have filled the user buffer, see if we should skip an
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* EOF character before releasing the lock and returning done.
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*/
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if (!nr)
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canon_skip_eof(ldata);
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else if (canon_copy_from_read_buf(tty, &kb, &nr))
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return kb - kbuf;
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} else {
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if (copy_from_read_buf(tty, &kb, &nr))
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return kb - kbuf;
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}
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+
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/* No more data - release locks and stop retries */
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n_tty_kick_worker(tty);
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n_tty_check_unthrottle(tty);
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up_read(&tty->termios_rwsem);
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mutex_unlock(&ldata->atomic_read_lock);
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*cookie = NULL;
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+
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return kb - kbuf;
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}
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/**
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* n_tty_read - read function for tty
···
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bool packet;
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size_t old_tail;
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/*
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* Is this a continuation of a read started earler?
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*
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* If so, we still hold the atomic_read_lock and the
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* termios_rwsem, and can just continue to copy data.
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*/
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if (*cookie) {
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if (ldata->icanon && !L_EXTPROC(tty)) {
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/*
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* If we have filled the user buffer, see
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* if we should skip an EOF character before
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* releasing the lock and returning done.
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*/
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-
if (!nr)
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canon_skip_eof(ldata);
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-
else if (canon_copy_from_read_buf(tty, &kb, &nr))
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return kb - kbuf;
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} else {
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if (copy_from_read_buf(tty, &kb, &nr))
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return kb - kbuf;
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}
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/* No more data - release locks and stop retries */
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n_tty_kick_worker(tty);
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n_tty_check_unthrottle(tty);
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up_read(&tty->termios_rwsem);
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mutex_unlock(&ldata->atomic_read_lock);
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*cookie = NULL;
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return kb - kbuf;
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-
}
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+
/* Is this a continuation of a read started earlier? */
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if (*cookie)
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return n_tty_continue_cookie(tty, kbuf, nr, cookie);
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retval = job_control(tty, file);
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if (retval < 0)