/* $NetBSD: xencons.c,v 1.41 2014/07/25 08:10:35 dholland Exp $ */ /* * Copyright (c) 2006 Manuel Bouyer. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * */ /* * * Copyright (c) 2004 Christian Limpach. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include __KERNEL_RCSID(0, "$NetBSD: xencons.c,v 1.41 2014/07/25 08:10:35 dholland Exp $"); #include "opt_xen.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef DDB #include /* XXX for db_max_line */ #endif #undef XENDEBUG #ifdef XENDEBUG #define XENPRINTK(x) printk x #else #define XENPRINTK(x) #endif static int xencons_isconsole = 0; static struct xencons_softc *xencons_console_device = NULL; #define XENCONS_UNIT(x) (minor(x)) #define XENCONS_BURST 128 int xencons_match(device_t, cfdata_t, void *); void xencons_attach(device_t, device_t, void *); int xencons_intr(void *); void xencons_tty_input(struct xencons_softc *, char*, int); struct xencons_softc { device_t sc_dev; struct tty *sc_tty; int polling; }; volatile struct xencons_interface *xencons_interface; CFATTACH_DECL_NEW(xencons, sizeof(struct xencons_softc), xencons_match, xencons_attach, NULL, NULL); extern struct cfdriver xencons_cd; dev_type_open(xencons_open); dev_type_close(xencons_close); dev_type_read(xencons_read); dev_type_write(xencons_write); dev_type_ioctl(xencons_ioctl); dev_type_stop(xencons_stop); dev_type_tty(xencons_tty); dev_type_poll(xencons_poll); const struct cdevsw xencons_cdevsw = { .d_open = xencons_open, .d_close = xencons_close, .d_read = xencons_read, .d_write = xencons_write, .d_ioctl = xencons_ioctl, .d_stop = xencons_stop, .d_tty = xencons_tty, .d_poll = xencons_poll, .d_mmap = NULL, /* XXX: is this safe? - dholland 20140315 */ .d_kqfilter = ttykqfilter, .d_discard = nodiscard, .d_flag = D_TTY }; static int xencons_handler(void *); int xenconscn_getc(dev_t); void xenconscn_putc(dev_t, int); void xenconscn_pollc(dev_t, int); static bool xencons_suspend(device_t, const pmf_qual_t *); static bool xencons_resume(device_t, const pmf_qual_t *); static struct consdev xencons = { NULL, NULL, xenconscn_getc, xenconscn_putc, xenconscn_pollc, NULL, NULL, NULL, NODEV, CN_NORMAL }; static struct cnm_state xencons_cnm_state; void xencons_start (struct tty *); int xencons_param (struct tty *, struct termios *); int xencons_match(device_t parent, cfdata_t match, void *aux) { struct xencons_attach_args *xa = (struct xencons_attach_args *)aux; if (strcmp(xa->xa_device, "xencons") == 0) return 1; return 0; } void xencons_attach(device_t parent, device_t self, void *aux) { struct xencons_softc *sc = device_private(self); aprint_normal(": Xen Virtual Console Driver\n"); sc->sc_dev = self; sc->sc_tty = tty_alloc(); tty_attach(sc->sc_tty); sc->sc_tty->t_oproc = xencons_start; sc->sc_tty->t_param = xencons_param; if (xencons_isconsole) { int maj; /* Locate the major number. */ maj = cdevsw_lookup_major(&xencons_cdevsw); /* There can be only one, but it can have any unit number. */ cn_tab->cn_dev = makedev(maj, device_unit(self)); aprint_verbose_dev(self, "console major %d, unit %d\n", maj, device_unit(self)); sc->sc_tty->t_dev = cn_tab->cn_dev; #ifdef DDB /* Set db_max_line to avoid paging. */ db_max_line = 0x7fffffff; #endif xencons_console_device = sc; xencons_resume(self, PMF_Q_NONE); } sc->polling = 0; if (!pmf_device_register(self, xencons_suspend, xencons_resume)) aprint_error_dev(self, "couldn't establish power handler\n"); } static bool xencons_suspend(device_t dev, const pmf_qual_t *qual) { int evtch; /* dom0 console should not be suspended */ if (!xendomain_is_dom0()) { evtch = xen_start_info.console_evtchn; hypervisor_mask_event(evtch); if (event_remove_handler(evtch, xencons_handler, xencons_console_device) != 0) { aprint_error_dev(dev, "can't remove handler: xencons_handler\n"); } aprint_verbose_dev(dev, "removed event channel %d\n", evtch); } return true; } static bool xencons_resume(device_t dev, const pmf_qual_t *qual) { int evtch = -1; if (xendomain_is_dom0()) { /* dom0 console resume is required only during first start-up */ if (cold) { evtch = bind_virq_to_evtch(VIRQ_CONSOLE); event_set_handler(evtch, xencons_intr, xencons_console_device, IPL_TTY, "xencons"); } } else { evtch = xen_start_info.console_evtchn; event_set_handler(evtch, xencons_handler, xencons_console_device, IPL_TTY, "xencons"); } if (evtch != -1) { aprint_verbose_dev(dev, "using event channel %d\n", evtch); hypervisor_enable_event(evtch); } return true; } int xencons_open(dev_t dev, int flag, int mode, struct lwp *l) { struct xencons_softc *sc; struct tty *tp; sc = device_lookup_private(&xencons_cd, XENCONS_UNIT(dev)); if (sc == NULL) return (ENXIO); tp = sc->sc_tty; if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp)) return (EBUSY); if ((tp->t_state & TS_ISOPEN) == 0 && tp->t_wopen == 0) { tp->t_dev = dev; ttychars(tp); tp->t_iflag = TTYDEF_IFLAG; tp->t_oflag = TTYDEF_OFLAG; tp->t_cflag = TTYDEF_CFLAG; tp->t_lflag = TTYDEF_LFLAG; tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED; xencons_param(tp, &tp->t_termios); ttsetwater(tp); } tp->t_state |= TS_CARR_ON; return ((*tp->t_linesw->l_open)(dev, tp)); } int xencons_close(dev_t dev, int flag, int mode, struct lwp *l) { struct xencons_softc *sc = device_lookup_private(&xencons_cd, XENCONS_UNIT(dev)); struct tty *tp = sc->sc_tty; if (tp == NULL) return (0); (*tp->t_linesw->l_close)(tp, flag); ttyclose(tp); #ifdef notyet /* XXX */ tty_free(tp); #endif return (0); } int xencons_read(dev_t dev, struct uio *uio, int flag) { struct xencons_softc *sc = device_lookup_private(&xencons_cd, XENCONS_UNIT(dev)); struct tty *tp = sc->sc_tty; return ((*tp->t_linesw->l_read)(tp, uio, flag)); } int xencons_write(dev_t dev, struct uio *uio, int flag) { struct xencons_softc *sc = device_lookup_private(&xencons_cd, XENCONS_UNIT(dev)); struct tty *tp = sc->sc_tty; return ((*tp->t_linesw->l_write)(tp, uio, flag)); } int xencons_poll(dev_t dev, int events, struct lwp *l) { struct xencons_softc *sc = device_lookup_private(&xencons_cd, XENCONS_UNIT(dev)); struct tty *tp = sc->sc_tty; return ((*tp->t_linesw->l_poll)(tp, events, l)); } struct tty * xencons_tty(dev_t dev) { struct xencons_softc *sc = device_lookup_private(&xencons_cd, XENCONS_UNIT(dev)); struct tty *tp = sc->sc_tty; return (tp); } int xencons_ioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l) { struct xencons_softc *sc = device_lookup_private(&xencons_cd, XENCONS_UNIT(dev)); struct tty *tp = sc->sc_tty; int error; error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l); if (error != EPASSTHROUGH) return (error); error = ttioctl(tp, cmd, data, flag, l); if (error != EPASSTHROUGH) return (error); switch (cmd) { default: return (EPASSTHROUGH); } #ifdef DIAGNOSTIC panic("xencons_ioctl: impossible"); #endif } void xencons_start(struct tty *tp) { struct clist *cl; int s; s = spltty(); if (tp->t_state & (TS_TIMEOUT | TS_BUSY | TS_TTSTOP)) goto out; tp->t_state |= TS_BUSY; splx(s); /* * We need to do this outside spl since it could be fairly * expensive and we don't want our serial ports to overflow. */ cl = &tp->t_outq; if (xendomain_is_dom0()) { int len, r; u_char buf[XENCONS_BURST+1]; len = q_to_b(cl, buf, XENCONS_BURST); while (len > 0) { r = HYPERVISOR_console_io(CONSOLEIO_write, len, buf); if (r <= 0) break; len -= r; } } else { XENCONS_RING_IDX cons, prod, len; #define XNC_OUT (xencons_interface->out) cons = xencons_interface->out_cons; prod = xencons_interface->out_prod; xen_rmb(); while (prod != cons + sizeof(xencons_interface->out)) { if (MASK_XENCONS_IDX(prod, XNC_OUT) < MASK_XENCONS_IDX(cons, XNC_OUT)) { len = MASK_XENCONS_IDX(cons, XNC_OUT) - MASK_XENCONS_IDX(prod, XNC_OUT); } else { len = sizeof(XNC_OUT) - MASK_XENCONS_IDX(prod, XNC_OUT); } len = q_to_b(cl, __UNVOLATILE( &XNC_OUT[MASK_XENCONS_IDX(prod, XNC_OUT)]), len); if (len == 0) break; prod = prod + len; } xen_wmb(); xencons_interface->out_prod = prod; xen_wmb(); hypervisor_notify_via_evtchn(xen_start_info.console.domU.evtchn); #undef XNC_OUT } s = spltty(); tp->t_state &= ~TS_BUSY; if (ttypull(tp)) { tp->t_state |= TS_TIMEOUT; callout_schedule(&tp->t_rstrt_ch, 1); } out: splx(s); } void xencons_stop(struct tty *tp, int flag) { } /* Non-privileged console interrupt routine */ static int xencons_handler(void *arg) { struct xencons_softc *sc = arg; XENCONS_RING_IDX cons, prod, len; int s = spltty(); if (sc->polling) { splx(s); return 1; } #define XNC_IN (xencons_interface->in) cons = xencons_interface->in_cons; prod = xencons_interface->in_prod; xen_rmb(); while (cons != prod) { if (MASK_XENCONS_IDX(cons, XNC_IN) < MASK_XENCONS_IDX(prod, XNC_IN)) len = MASK_XENCONS_IDX(prod, XNC_IN) - MASK_XENCONS_IDX(cons, XNC_IN); else len = sizeof(XNC_IN) - MASK_XENCONS_IDX(cons, XNC_IN); xencons_tty_input(sc, __UNVOLATILE( &XNC_IN[MASK_XENCONS_IDX(cons, XNC_IN)]), len); if (__predict_false(xencons_interface->in_cons != cons)) { /* catch up with xenconscn_getc() */ cons = xencons_interface->in_cons; prod = xencons_interface->in_prod; xen_rmb(); } else { cons += len; xen_wmb(); xencons_interface->in_cons = cons; xen_wmb(); } } hypervisor_notify_via_evtchn(xen_start_info.console.domU.evtchn); splx(s); return 1; #undef XNC_IN } void xencons_tty_input(struct xencons_softc *sc, char* buf, int len) { struct tty *tp; int i; tp = sc->sc_tty; if (tp == NULL) return; for (i = 0; i < len; i++) { cn_check_magic(sc->sc_tty->t_dev, buf[i], xencons_cnm_state); (*tp->t_linesw->l_rint)(buf[i], tp); } } /* privileged receive callback */ int xencons_intr(void *p) { static char rbuf[16]; int len; struct xencons_softc *sc = p; if (sc == NULL) /* Interrupt may happen during resume */ return 1; if (sc->polling) return 1; while ((len = HYPERVISOR_console_io(CONSOLEIO_read, sizeof(rbuf), rbuf)) > 0) { xencons_tty_input(sc, rbuf, len); } return 1; } void xenconscn_attach(void) { cn_tab = &xencons; /* console ring mapped in locore.S */ cn_init_magic(&xencons_cnm_state); cn_set_magic("+++++"); xencons_isconsole = 1; } int xenconscn_getc(dev_t dev) { char c; int s = spltty(); XENCONS_RING_IDX cons, prod; if (xencons_console_device && xencons_console_device->polling == 0) { printf("xenconscn_getc() but not polling\n"); splx(s); return 0; } if (xendomain_is_dom0()) { while (HYPERVISOR_console_io(CONSOLEIO_read, 1, &c) == 0) ; cn_check_magic(dev, c, xencons_cnm_state); splx(s); return c; } if (xencons_console_device == NULL) { printf("xenconscn_getc(): not console\n"); while (1) ; /* loop here instead of in ddb */ splx(s); return 0; } if (xencons_console_device->polling == 0) { printf("xenconscn_getc() but not polling\n"); splx(s); return 0; } cons = xencons_interface->in_cons; prod = xencons_interface->in_prod; xen_rmb(); while (cons == prod) { HYPERVISOR_yield(); prod = xencons_interface->in_prod; } xen_rmb(); c = xencons_interface->in[MASK_XENCONS_IDX(xencons_interface->in_cons, xencons_interface->in)]; xen_rmb(); xencons_interface->in_cons = cons + 1; cn_check_magic(dev, c, xencons_cnm_state); splx(s); return c; } void xenconscn_putc(dev_t dev, int c) { int s = spltty(); XENCONS_RING_IDX cons, prod; if (xendomain_is_dom0()) { u_char buf[1]; buf[0] = c; (void)HYPERVISOR_console_io(CONSOLEIO_write, 1, buf); } else { XENPRINTK(("xenconscn_putc(%c)\n", c)); cons = xencons_interface->out_cons; prod = xencons_interface->out_prod; xen_rmb(); while (prod == cons + sizeof(xencons_interface->out)) { cons = xencons_interface->out_cons; prod = xencons_interface->out_prod; xen_rmb(); } xencons_interface->out[MASK_XENCONS_IDX(xencons_interface->out_prod, xencons_interface->out)] = c; xen_rmb(); xencons_interface->out_prod++; xen_rmb(); hypervisor_notify_via_evtchn(xen_start_info.console.domU.evtchn); splx(s); } } void xenconscn_pollc(dev_t dev, int on) { if (xencons_console_device) xencons_console_device->polling = on; } /* * Set line parameters. */ int xencons_param(struct tty *tp, struct termios *t) { tp->t_ispeed = t->c_ispeed; tp->t_ospeed = t->c_ospeed; tp->t_cflag = t->c_cflag; return (0); }