From 679e7c2999f963e542c6f4c3d3c9a0688b5d3587 Mon Sep 17 00:00:00 2001 From: Peter Hurley Date: Fri, 27 Nov 2015 14:11:02 -0500 Subject: [PATCH] n_tty: Uninline tty_copy_to_user() Merge the multiple tty_copy_to_user() calls into a single copy sequence within tty_copy_to_user(). Signed-off-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman --- drivers/tty/n_tty.c | 33 ++++++++++++++++++--------------- 1 file changed, 18 insertions(+), 15 deletions(-) diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c index c37c15d2f782..b2b01d5439b7 100644 --- a/drivers/tty/n_tty.c +++ b/drivers/tty/n_tty.c @@ -162,12 +162,23 @@ static inline int tty_put_user(struct tty_struct *tty, unsigned char x, return put_user(x, ptr); } -static inline int tty_copy_to_user(struct tty_struct *tty, - void __user *to, - const void *from, - unsigned long n) +static int tty_copy_to_user(struct tty_struct *tty, void __user *to, + size_t tail, size_t n) { struct n_tty_data *ldata = tty->disc_data; + size_t size = N_TTY_BUF_SIZE - tail; + const void *from = read_buf_addr(ldata, tail); + int uncopied; + + if (n > size) { + tty_audit_add_data(tty, from, size, ldata->icanon); + uncopied = copy_to_user(to, from, size); + if (uncopied) + return uncopied; + to += size; + n -= size; + from = ldata->read_buf; + } tty_audit_add_data(tty, from, n, ldata->icanon); return copy_to_user(to, from, n); @@ -2074,7 +2085,6 @@ static int canon_copy_from_read_buf(struct tty_struct *tty, } else if (eol != size) found = 1; - size = N_TTY_BUF_SIZE - tail; n = eol - tail; if (n > N_TTY_BUF_SIZE) n += N_TTY_BUF_SIZE; @@ -2086,17 +2096,10 @@ static int canon_copy_from_read_buf(struct tty_struct *tty, eof_push = !n && ldata->read_tail != ldata->line_start; } - n_tty_trace("%s: eol:%zu found:%d n:%zu c:%zu size:%zu more:%zu\n", - __func__, eol, found, n, c, size, more); - - if (n > size) { - ret = tty_copy_to_user(tty, *b, read_buf_addr(ldata, tail), size); - if (ret) - return -EFAULT; - ret = tty_copy_to_user(tty, *b + size, ldata->read_buf, n - size); - } else - ret = tty_copy_to_user(tty, *b, read_buf_addr(ldata, tail), n); + n_tty_trace("%s: eol:%zu found:%d n:%zu c:%zu tail:%zu more:%zu\n", + __func__, eol, found, n, c, tail, more); + ret = tty_copy_to_user(tty, *b, tail, n); if (ret) return -EFAULT; *b += n; -- 2.39.5