diff options
Diffstat (limited to 'drivers/tty/n_tty.c')
| -rw-r--r-- | drivers/tty/n_tty.c | 22 |
1 files changed, 9 insertions, 13 deletions
diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c index f2f64252814f..d9a5fc28fef4 100644 --- a/drivers/tty/n_tty.c +++ b/drivers/tty/n_tty.c @@ -2062,13 +2062,13 @@ static int canon_copy_from_read_buf(struct tty_struct *tty, size_t eol; size_t tail; int ret, found = 0; - bool eof_push = 0; /* N.B. avoid overrun if nr == 0 */ - n = min(*nr, smp_load_acquire(&ldata->canon_head) - ldata->read_tail); - if (!n) + if (!*nr) return 0; + n = min(*nr + 1, smp_load_acquire(&ldata->canon_head) - ldata->read_tail); + tail = ldata->read_tail & (N_TTY_BUF_SIZE - 1); size = min_t(size_t, tail + n, N_TTY_BUF_SIZE); @@ -2087,12 +2087,11 @@ static int canon_copy_from_read_buf(struct tty_struct *tty, n = eol - tail; if (n > N_TTY_BUF_SIZE) n += N_TTY_BUF_SIZE; - n += found; - c = n; + c = n + found; - if (found && !ldata->push && read_buf(ldata, eol) == __DISABLED_CHAR) { - n--; - eof_push = !n && ldata->read_tail != ldata->line_start; + if (!found || read_buf(ldata, eol) != __DISABLED_CHAR) { + c = min(*nr, c); + n = c; } n_tty_trace("%s: eol:%zu found:%d n:%zu c:%zu tail:%zu more:%zu\n", @@ -2115,7 +2114,7 @@ static int canon_copy_from_read_buf(struct tty_struct *tty, ldata->push = 0; tty_audit_push(tty); } - return eof_push ? -EAGAIN : 0; + return 0; } extern ssize_t redirected_tty_write(struct file *, const char __user *, @@ -2272,10 +2271,7 @@ static ssize_t n_tty_read(struct tty_struct *tty, struct file *file, if (ldata->icanon && !L_EXTPROC(tty)) { retval = canon_copy_from_read_buf(tty, &b, &nr); - if (retval == -EAGAIN) { - retval = 0; - continue; - } else if (retval) + if (retval) break; } else { int uncopied; |