diff options
Diffstat (limited to 'sys/kern/tty.c')
| -rw-r--r-- | sys/kern/tty.c | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/sys/kern/tty.c b/sys/kern/tty.c index b8eff2c..0d124a2 100644 --- a/sys/kern/tty.c +++ b/sys/kern/tty.c @@ -91,6 +91,7 @@ #include <sys/resourcevar.h> #include <sys/malloc.h> #include <sys/filedesc.h> +#include <sys/linker.h> #if NSNP > 0 #include <sys/snoop.h> #endif @@ -113,6 +114,7 @@ static void ttyrub __P((int c, struct tty *tp)); static void ttyrubo __P((struct tty *tp, int cnt)); static void ttyunblock __P((struct tty *tp)); static int ttywflush __P((struct tty *tp)); +static int tty_load_disc __P((int t)); /* * Table with character classes and parity. The 8th bit indicates parity, @@ -201,6 +203,23 @@ static u_char const char_type[] = { static SLIST_HEAD(, tty) tty_list; /* + * Some line disciplines may exist as external KLD modules. + * Put them here and they will be automatically loaded + * whenever someone attempts to install the corresponding + * line discipline. + */ +static struct tty_kldinfo { + int discnum; /* line discipline number, -1 ends */ + const char *filename; /* name of the KLD file */ + int loaded; /* set to 1 if already loaded */ +} tty_ldisc_klds[] = { + { SLIPDISC, "if_sl.ko" }, + { PPPDISC, "if_ppp.ko" }, + { NETGRAPHDISC, "ng_tty.ko" }, + { -1 } +}; + +/* * Initial open of tty, or (re)entry to standard tty line discipline. */ int @@ -960,6 +979,8 @@ ttioctl(tp, cmd, data, flag) s = spltty(); (*linesw[tp->t_line].l_close)(tp, flag); error = (*linesw[t].l_open)(device, tp); + if (error == ENODEV && tty_load_disc(t)) /* try KLD */ + error = (*linesw[t].l_open)(device, tp); if (error) { (void)(*linesw[tp->t_line].l_open)(device, tp); splx(s); @@ -1225,6 +1246,42 @@ again: } /* + * Try to load the KLD for the line discipline, if one exists. + * Returns 1 on success, zero on failure. + */ +static int +tty_load_disc(int t) +{ + struct tty_kldinfo *kld; + linker_file_t lf; + int error; + char *path; + + for (kld = &tty_ldisc_klds[0]; kld->discnum != -1; kld++) { + if (kld->discnum == t) { + + /* Don't load the same KLD twice */ + if (kld->loaded) + break; + + /* Try loading the KLD */ + if ((path = linker_search_path(kld->filename)) == NULL) + return 0; + error = linker_load_file(path, &lf); + FREE(path, M_LINKER); + if (error != 0) + return 0; + lf->userrefs++; /* as if by kldload(2) */ + + /* Mark KLD as loaded and return success */ + kld->loaded = 1; + return 1; + } + } + return 0; +} + +/* * Copy in the default termios characters. */ void |
