ng_tty.c revision 151387
152419Sjulian/* 252419Sjulian * ng_tty.c 3139823Simp */ 4139823Simp 5139823Simp/*- 652419Sjulian * Copyright (c) 1996-1999 Whistle Communications, Inc. 752419Sjulian * All rights reserved. 852419Sjulian * 952419Sjulian * Subject to the following obligations and disclaimer of warranty, use and 1052419Sjulian * redistribution of this software, in source or object code forms, with or 1152419Sjulian * without modifications are expressly permitted by Whistle Communications; 1252419Sjulian * provided, however, that: 1352419Sjulian * 1. Any and all reproductions of the source or object code must include the 1452419Sjulian * copyright notice above and the following disclaimer of warranties; and 1552419Sjulian * 2. No rights are granted, in any manner or form, to use Whistle 1652419Sjulian * Communications, Inc. trademarks, including the mark "WHISTLE 1752419Sjulian * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 1852419Sjulian * such appears in the above copyright notice or in the software. 1952419Sjulian * 2052419Sjulian * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 2152419Sjulian * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 2252419Sjulian * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 2352419Sjulian * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 2452419Sjulian * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 2552419Sjulian * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 2652419Sjulian * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 2752419Sjulian * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 2852419Sjulian * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 2952419Sjulian * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 3052419Sjulian * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 3152419Sjulian * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 3252419Sjulian * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 3352419Sjulian * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 3452419Sjulian * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 3552419Sjulian * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 3652419Sjulian * OF SUCH DAMAGE. 3752419Sjulian * 3867506Sjulian * Author: Archie Cobbs <archie@freebsd.org> 3952419Sjulian * 4052419Sjulian * $FreeBSD: head/sys/netgraph/ng_tty.c 151387 2005-10-16 20:44:18Z phk $ 4152752Sjulian * $Whistle: ng_tty.c,v 1.21 1999/11/01 09:24:52 julian Exp $ 4252419Sjulian */ 4352419Sjulian 4452419Sjulian/* 4552419Sjulian * This file implements a terminal line discipline that is also a 4652419Sjulian * netgraph node. Installing this line discipline on a terminal device 4752419Sjulian * instantiates a new netgraph node of this type, which allows access 4852419Sjulian * to the device via the "hook" hook of the node. 4952419Sjulian * 5052419Sjulian * Once the line discipline is installed, you can find out the name 5152419Sjulian * of the corresponding netgraph node via a NGIOCGINFO ioctl(). 5252419Sjulian * 5352419Sjulian * Incoming characters are delievered to the hook one at a time, each 5452419Sjulian * in its own mbuf. You may optionally define a ``hotchar,'' which causes 5552419Sjulian * incoming characters to be buffered up until either the hotchar is 5652419Sjulian * seen or the mbuf is full (MHLEN bytes). Then all buffered characters 5752419Sjulian * are immediately delivered. 5852419Sjulian */ 5952419Sjulian 6052419Sjulian#include <sys/param.h> 6152419Sjulian#include <sys/systm.h> 62140164Sglebius#include <sys/conf.h> 63140164Sglebius#include <sys/errno.h> 64140164Sglebius#include <sys/fcntl.h> 65140164Sglebius#include <sys/ioccom.h> 6652419Sjulian#include <sys/kernel.h> 67140164Sglebius#include <sys/malloc.h> 6852419Sjulian#include <sys/mbuf.h> 69140164Sglebius#include <sys/socket.h> 70140164Sglebius#include <sys/syslog.h> 7152419Sjulian#include <sys/tty.h> 7252441Sjulian#include <sys/ttycom.h> 7352419Sjulian 74140164Sglebius#include <net/if.h> 75140164Sglebius#include <net/if_var.h> 76140164Sglebius 7752419Sjulian#include <netgraph/ng_message.h> 7852419Sjulian#include <netgraph/netgraph.h> 7952419Sjulian#include <netgraph/ng_tty.h> 8052419Sjulian 8152419Sjulian/* Misc defs */ 8252419Sjulian#define MAX_MBUFQ 3 /* Max number of queued mbufs */ 8352419Sjulian#define NGT_HIWATER 400 /* High water mark on output */ 8452419Sjulian 8552419Sjulian/* Per-node private info */ 8652419Sjulianstruct ngt_sc { 8753913Sarchie struct tty *tp; /* Terminal device */ 8853913Sarchie node_p node; /* Netgraph node */ 8953913Sarchie hook_p hook; /* Netgraph hook */ 90140164Sglebius struct ifqueue outq; /* Queue of outgoing data */ 9153913Sarchie struct mbuf *m; /* Incoming data buffer */ 9253913Sarchie short hotchar; /* Hotchar, or -1 if none */ 9353913Sarchie u_int flags; /* Flags */ 94138420Sglebius struct callout chand; /* See man timeout(9) */ 9552419Sjulian}; 9652419Sjuliantypedef struct ngt_sc *sc_p; 9752419Sjulian 9852419Sjulian/* Flags */ 9952419Sjulian#define FLG_DEBUG 0x0002 100140164Sglebius#define FLG_DIE 0x0004 10152419Sjulian 10252419Sjulian/* Line discipline methods */ 103130585Sphkstatic int ngt_open(struct cdev *dev, struct tty *tp); 10452419Sjulianstatic int ngt_close(struct tty *tp, int flag); 10552419Sjulianstatic int ngt_read(struct tty *tp, struct uio *uio, int flag); 10652419Sjulianstatic int ngt_write(struct tty *tp, struct uio *uio, int flag); 10752419Sjulianstatic int ngt_tioctl(struct tty *tp, 10883366Sjulian u_long cmd, caddr_t data, int flag, struct thread *); 10952419Sjulianstatic int ngt_input(int c, struct tty *tp); 11052419Sjulianstatic int ngt_start(struct tty *tp); 11152419Sjulian 11252419Sjulian/* Netgraph methods */ 11352752Sjulianstatic ng_constructor_t ngt_constructor; 11452752Sjulianstatic ng_rcvmsg_t ngt_rcvmsg; 11552752Sjulianstatic ng_shutdown_t ngt_shutdown; 11652752Sjulianstatic ng_newhook_t ngt_newhook; 11769922Sjulianstatic ng_connect_t ngt_connect; 11852752Sjulianstatic ng_rcvdata_t ngt_rcvdata; 11952752Sjulianstatic ng_disconnect_t ngt_disconnect; 120140164Sglebiusstatic int ngt_mod_event(module_t mod, int event, void *data); 12152419Sjulian 12252419Sjulian/* Other stuff */ 123138420Sglebiusstatic void ngt_timeout(node_p node, hook_p hook, void *arg1, int arg2); 12452419Sjulian 12552419Sjulian#define ERROUT(x) do { error = (x); goto done; } while (0) 12652419Sjulian 12752419Sjulian/* Line discipline descriptor */ 12852419Sjulianstatic struct linesw ngt_disc = { 129140164Sglebius .l_open = ngt_open, 130140164Sglebius .l_close = ngt_close, 131140164Sglebius .l_read = ngt_read, 132140164Sglebius .l_write = ngt_write, 133140164Sglebius .l_ioctl = ngt_tioctl, 134140164Sglebius .l_rint = ngt_input, 135140164Sglebius .l_start = ngt_start, 136140164Sglebius .l_modem = ttymodem, 13752419Sjulian}; 13852419Sjulian 13952419Sjulian/* Netgraph node type descriptor */ 14052419Sjulianstatic struct ng_type typestruct = { 141129823Sjulian .version = NG_ABI_VERSION, 142129823Sjulian .name = NG_TTY_NODE_TYPE, 143129823Sjulian .mod_event = ngt_mod_event, 144129823Sjulian .constructor = ngt_constructor, 145129823Sjulian .rcvmsg = ngt_rcvmsg, 146129823Sjulian .shutdown = ngt_shutdown, 147129823Sjulian .newhook = ngt_newhook, 148129823Sjulian .connect = ngt_connect, 149129823Sjulian .rcvdata = ngt_rcvdata, 150129823Sjulian .disconnect = ngt_disconnect, 15152419Sjulian}; 15252419SjulianNETGRAPH_INIT(tty, &typestruct); 15352419Sjulian 154132163Srwatson/* 155140164Sglebius * Locking: 156140164Sglebius * 157140164Sglebius * - node private data and tp->t_lsc is protected by mutex in struct 158140164Sglebius * ifqueue, locking is done using IF_XXX() macros. 159140164Sglebius * - in all tty methods we should acquire node ifqueue mutex, when accessing 160140164Sglebius * private data. 161140164Sglebius * - in _rcvdata() we should use locked versions of IF_{EN,DE}QUEUE() since 162140164Sglebius * we may have multiple _rcvdata() threads. 163140164Sglebius * - when calling any of tty methods from netgraph methods, we should 164140164Sglebius * acquire tty locking (now Giant). 165140164Sglebius * 166140164Sglebius * - ngt_unit is incremented atomically. 167132163Srwatson */ 168140164Sglebius 169140164Sglebius#define NGTLOCK(sc) IF_LOCK(&sc->outq) 170140164Sglebius#define NGTUNLOCK(sc) IF_UNLOCK(&sc->outq) 171140164Sglebius 17252419Sjulianstatic int ngt_unit; 17352442Sjulianstatic int ngt_ldisc; 17452419Sjulian 17552419Sjulian/****************************************************************** 17652419Sjulian LINE DISCIPLINE METHODS 17752419Sjulian******************************************************************/ 17852419Sjulian 17952419Sjulian/* 18052419Sjulian * Set our line discipline on the tty. 181140164Sglebius * Called from device open routine or ttioctl() 18252419Sjulian */ 18352419Sjulianstatic int 184130585Sphkngt_open(struct cdev *dev, struct tty *tp) 18552419Sjulian{ 18683366Sjulian struct thread *const td = curthread; /* XXX */ 18752419Sjulian char name[sizeof(NG_TTY_NODE_TYPE) + 8]; 18852419Sjulian sc_p sc; 189140164Sglebius int error; 19052419Sjulian 19152419Sjulian /* Super-user only */ 19293593Sjhb if ((error = suser(td))) 19352419Sjulian return (error); 19452419Sjulian 19552419Sjulian /* Initialize private struct */ 196111119Simp MALLOC(sc, sc_p, sizeof(*sc), M_NETGRAPH, M_WAITOK | M_ZERO); 197140164Sglebius if (sc == NULL) 198140164Sglebius return (ENOMEM); 199140164Sglebius 20052419Sjulian sc->tp = tp; 201140164Sglebius sc->hotchar = tp->t_hotchar = NG_TTY_DFL_HOTCHAR; 202140164Sglebius mtx_init(&sc->outq.ifq_mtx, "ng_tty node+queue", NULL, MTX_DEF); 203140164Sglebius IFQ_SET_MAXLEN(&sc->outq, MAX_MBUFQ); 20452419Sjulian 205140164Sglebius NGTLOCK(sc); 206140164Sglebius 20752419Sjulian /* Setup netgraph node */ 20852419Sjulian error = ng_make_node_common(&typestruct, &sc->node); 20952419Sjulian if (error) { 210140164Sglebius NGTUNLOCK(sc); 21152419Sjulian FREE(sc, M_NETGRAPH); 212140164Sglebius return (error); 21352419Sjulian } 21452419Sjulian 215140164Sglebius atomic_add_int(&ngt_unit, 1); 216140164Sglebius snprintf(name, sizeof(name), "%s%d", typestruct.name, ngt_unit); 217140164Sglebius 21852419Sjulian /* Assign node its name */ 21952419Sjulian if ((error = ng_name_node(sc->node, name))) { 220140164Sglebius sc->flags |= FLG_DIE; 221140164Sglebius NGTUNLOCK(sc); 222140164Sglebius NG_NODE_UNREF(sc->node); 22352419Sjulian log(LOG_ERR, "%s: node name exists?\n", name); 224140164Sglebius return (error); 22552419Sjulian } 22652419Sjulian 22770700Sjulian /* Set back pointers */ 22870784Sjulian NG_NODE_SET_PRIVATE(sc->node, sc); 229135406Sphk tp->t_lsc = sc; 23070700Sjulian 231140164Sglebius ng_callout_init(&sc->chand); 232140164Sglebius 23352419Sjulian /* 23452419Sjulian * Pre-allocate cblocks to the an appropriate amount. 23552419Sjulian * I'm not sure what is appropriate. 23652419Sjulian */ 23752419Sjulian ttyflush(tp, FREAD | FWRITE); 23852419Sjulian clist_alloc_cblocks(&tp->t_canq, 0, 0); 23952419Sjulian clist_alloc_cblocks(&tp->t_rawq, 0, 0); 24052419Sjulian clist_alloc_cblocks(&tp->t_outq, 24152419Sjulian MLEN + NGT_HIWATER, MLEN + NGT_HIWATER); 24252419Sjulian 243140164Sglebius NGTUNLOCK(sc); 244140164Sglebius 245140164Sglebius return (0); 24652419Sjulian} 24752419Sjulian 24852419Sjulian/* 24952419Sjulian * Line specific close routine, called from device close routine 250140164Sglebius * and from ttioctl. This causes the node to be destroyed as well. 25152419Sjulian */ 25252419Sjulianstatic int 25352419Sjulianngt_close(struct tty *tp, int flag) 25452419Sjulian{ 255135406Sphk const sc_p sc = (sc_p) tp->t_lsc; 25652419Sjulian 25752419Sjulian ttyflush(tp, FREAD | FWRITE); 25852419Sjulian clist_free_cblocks(&tp->t_outq); 25952419Sjulian if (sc != NULL) { 260140164Sglebius NGTLOCK(sc); 261140164Sglebius if (callout_pending(&sc->chand)) 262138420Sglebius ng_uncallout(&sc->chand, sc->node); 263140164Sglebius tp->t_lsc = NULL; 264140164Sglebius sc->flags |= FLG_DIE; 265140164Sglebius NGTUNLOCK(sc); 26670700Sjulian ng_rmnode_self(sc->node); 26752419Sjulian } 26852419Sjulian return (0); 26952419Sjulian} 27052419Sjulian 27152419Sjulian/* 27252419Sjulian * Once the device has been turned into a node, we don't allow reading. 27352419Sjulian */ 27452419Sjulianstatic int 27552419Sjulianngt_read(struct tty *tp, struct uio *uio, int flag) 27652419Sjulian{ 27752419Sjulian return (EIO); 27852419Sjulian} 27952419Sjulian 28052419Sjulian/* 28152419Sjulian * Once the device has been turned into a node, we don't allow writing. 28252419Sjulian */ 28352419Sjulianstatic int 28452419Sjulianngt_write(struct tty *tp, struct uio *uio, int flag) 28552419Sjulian{ 28652419Sjulian return (EIO); 28752419Sjulian} 28852419Sjulian 28952419Sjulian/* 29052419Sjulian * We implement the NGIOCGINFO ioctl() defined in ng_message.h. 29152419Sjulian */ 29252419Sjulianstatic int 29383366Sjulianngt_tioctl(struct tty *tp, u_long cmd, caddr_t data, int flag, struct thread *td) 29452419Sjulian{ 295135406Sphk const sc_p sc = (sc_p) tp->t_lsc; 29652419Sjulian 297140164Sglebius if (sc == NULL) 298140164Sglebius /* No node attached */ 299140164Sglebius return (0); 300140164Sglebius 30152419Sjulian switch (cmd) { 30252419Sjulian case NGIOCGINFO: 30352419Sjulian { 30452419Sjulian struct nodeinfo *const ni = (struct nodeinfo *) data; 30552419Sjulian const node_p node = sc->node; 30652419Sjulian 30752419Sjulian bzero(ni, sizeof(*ni)); 308140164Sglebius NGTLOCK(sc); 30970784Sjulian if (NG_NODE_HAS_NAME(node)) 31070784Sjulian strncpy(ni->name, NG_NODE_NAME(node), sizeof(ni->name) - 1); 31170784Sjulian strncpy(ni->type, node->nd_type->name, sizeof(ni->type) - 1); 31270784Sjulian ni->id = (u_int32_t) ng_node2ID(node); 31370784Sjulian ni->hooks = NG_NODE_NUMHOOKS(node); 314140164Sglebius NGTUNLOCK(sc); 31552419Sjulian break; 31652419Sjulian } 31752419Sjulian default: 318140164Sglebius return (ENOIOCTL); 31952419Sjulian } 320140164Sglebius 321140164Sglebius return (0); 32252419Sjulian} 32352419Sjulian 32452419Sjulian/* 32552419Sjulian * Receive data coming from the device. We get one character at 32652419Sjulian * a time, which is kindof silly. 327140164Sglebius * 328140164Sglebius * Full locking of softc is not required, since we are the only 329140164Sglebius * user of sc->m. 33052419Sjulian */ 33152419Sjulianstatic int 33252419Sjulianngt_input(int c, struct tty *tp) 33352419Sjulian{ 334151085Stanimura sc_p sc; 335151085Stanimura node_p node; 33652419Sjulian struct mbuf *m; 337140164Sglebius int error = 0; 33852419Sjulian 339151085Stanimura sc = (sc_p) tp->t_lsc; 340140164Sglebius if (sc == NULL) 341140164Sglebius /* No node attached */ 34252419Sjulian return (0); 34352419Sjulian 344151085Stanimura node = sc->node; 345151085Stanimura 346140164Sglebius if (tp != sc->tp) 347140164Sglebius panic("ngt_input"); 348140164Sglebius 34952419Sjulian /* Check for error conditions */ 35052419Sjulian if ((tp->t_state & TS_CONNECTED) == 0) { 35152419Sjulian if (sc->flags & FLG_DEBUG) 35270784Sjulian log(LOG_DEBUG, "%s: no carrier\n", NG_NODE_NAME(node)); 353140164Sglebius return (0); 35452419Sjulian } 35552419Sjulian if (c & TTY_ERRORMASK) { 35652419Sjulian /* framing error or overrun on this char */ 35752419Sjulian if (sc->flags & FLG_DEBUG) 35852419Sjulian log(LOG_DEBUG, "%s: line error %x\n", 35970784Sjulian NG_NODE_NAME(node), c & TTY_ERRORMASK); 360140164Sglebius return (0); 36152419Sjulian } 36252419Sjulian c &= TTY_CHARMASK; 36352419Sjulian 36452419Sjulian /* Get a new header mbuf if we need one */ 36552419Sjulian if (!(m = sc->m)) { 366111119Simp MGETHDR(m, M_DONTWAIT, MT_DATA); 36752419Sjulian if (!m) { 36852419Sjulian if (sc->flags & FLG_DEBUG) 36952419Sjulian log(LOG_ERR, 37070784Sjulian "%s: can't get mbuf\n", NG_NODE_NAME(node)); 371140164Sglebius return (ENOBUFS); 37252419Sjulian } 37353284Sarchie m->m_len = m->m_pkthdr.len = 0; 37453284Sarchie m->m_pkthdr.rcvif = NULL; 37552419Sjulian sc->m = m; 37652419Sjulian } 37752419Sjulian 37852419Sjulian /* Add char to mbuf */ 37952419Sjulian *mtod(m, u_char *) = c; 38052419Sjulian m->m_data++; 38152419Sjulian m->m_len++; 38252419Sjulian m->m_pkthdr.len++; 38352419Sjulian 38452419Sjulian /* Ship off mbuf if it's time */ 38552419Sjulian if (sc->hotchar == -1 || c == sc->hotchar || m->m_len >= MHLEN) { 38652419Sjulian m->m_data = m->m_pktdat; 38752419Sjulian sc->m = NULL; 388140164Sglebius 389140164Sglebius /* 390140164Sglebius * We have built our mbuf without checking that we actually 391140164Sglebius * have a hook to send it. This was done to avoid 392140164Sglebius * acquiring mutex on each character. Check now. 393140164Sglebius * 394140164Sglebius */ 395140164Sglebius 396140164Sglebius NGTLOCK(sc); 397140164Sglebius if (sc->hook == NULL) { 398140164Sglebius NGTUNLOCK(sc); 399140164Sglebius m_freem(m); 400140164Sglebius return (0); /* XXX: original behavior */ 401140164Sglebius } 402140164Sglebius NG_SEND_DATA_ONLY(error, sc->hook, m); /* Will queue */ 403140164Sglebius NGTUNLOCK(sc); 40452419Sjulian } 405140164Sglebius 40652419Sjulian return (error); 40752419Sjulian} 40852419Sjulian 40952419Sjulian/* 41052419Sjulian * This is called when the device driver is ready for more output. 411140164Sglebius * Also called from ngt_rcv_data() when a new mbuf is available for output. 41252419Sjulian */ 41352419Sjulianstatic int 41452419Sjulianngt_start(struct tty *tp) 41552419Sjulian{ 416135406Sphk const sc_p sc = (sc_p) tp->t_lsc; 41752419Sjulian 41852419Sjulian while (tp->t_outq.c_cc < NGT_HIWATER) { /* XXX 2.2 specific ? */ 419140164Sglebius struct mbuf *m; 42052419Sjulian 42152419Sjulian /* Remove first mbuf from queue */ 422140164Sglebius IF_DEQUEUE(&sc->outq, m); 423140164Sglebius if (m == NULL) 42452419Sjulian break; 42552419Sjulian 42652419Sjulian /* Send as much of it as possible */ 427140164Sglebius while (m != NULL) { 42852419Sjulian int sent; 42952419Sjulian 43052419Sjulian sent = m->m_len 43152419Sjulian - b_to_q(mtod(m, u_char *), m->m_len, &tp->t_outq); 43252419Sjulian m->m_data += sent; 43352419Sjulian m->m_len -= sent; 43452419Sjulian if (m->m_len > 0) 43552419Sjulian break; /* device can't take no more */ 43690227Sdillon m = m_free(m); 43752419Sjulian } 43852419Sjulian 43952419Sjulian /* Put remainder of mbuf chain (if any) back on queue */ 440140164Sglebius if (m != NULL) { 441140164Sglebius IF_PREPEND(&sc->outq, m); 44252419Sjulian break; 44352419Sjulian } 44452419Sjulian } 44552419Sjulian 44652419Sjulian /* Call output process whether or not there is any output. We are 44752419Sjulian * being called in lieu of ttstart and must do what it would. */ 448151387Sphk tt_oproc(tp); 44952419Sjulian 45052419Sjulian /* This timeout is needed for operation on a pseudo-tty, because the 45152419Sjulian * pty code doesn't call pppstart after it has drained the t_outq. */ 452140164Sglebius /* XXX: outq not locked */ 453140164Sglebius if (!IFQ_IS_EMPTY(&sc->outq) && !callout_pending(&sc->chand)) 454138420Sglebius ng_callout(&sc->chand, sc->node, NULL, 1, ngt_timeout, NULL, 0); 455140164Sglebius 45652419Sjulian return (0); 45752419Sjulian} 45852419Sjulian 45952419Sjulian/* 46052419Sjulian * We still have data to output to the device, so try sending more. 46152419Sjulian */ 46252419Sjulianstatic void 463138420Sglebiusngt_timeout(node_p node, hook_p hook, void *arg1, int arg2) 46452419Sjulian{ 465138420Sglebius const sc_p sc = NG_NODE_PRIVATE(node); 46652419Sjulian 467140164Sglebius mtx_lock(&Giant); 46852419Sjulian ngt_start(sc->tp); 469140164Sglebius mtx_unlock(&Giant); 47052419Sjulian} 47152419Sjulian 47252419Sjulian/****************************************************************** 47352419Sjulian NETGRAPH NODE METHODS 47452419Sjulian******************************************************************/ 47552419Sjulian 47652419Sjulian/* 47752419Sjulian * Initialize a new node of this type. 47852419Sjulian * 47952419Sjulian * We only allow nodes to be created as a result of setting 48052419Sjulian * the line discipline on a tty, so always return an error if not. 48152419Sjulian */ 48252419Sjulianstatic int 48370700Sjulianngt_constructor(node_p node) 48452419Sjulian{ 48570700Sjulian return (EOPNOTSUPP); 48652419Sjulian} 48752419Sjulian 48852419Sjulian/* 48952419Sjulian * Add a new hook. There can only be one. 49052419Sjulian */ 49152419Sjulianstatic int 49252419Sjulianngt_newhook(node_p node, hook_p hook, const char *name) 49352419Sjulian{ 49470784Sjulian const sc_p sc = NG_NODE_PRIVATE(node); 49552419Sjulian 49652419Sjulian if (strcmp(name, NG_TTY_HOOK)) 49752419Sjulian return (EINVAL); 498140164Sglebius 49952419Sjulian if (sc->hook) 500140164Sglebius return (EISCONN); 501140164Sglebius 502140164Sglebius NGTLOCK(sc); 50352419Sjulian sc->hook = hook; 504140164Sglebius NGTUNLOCK(sc); 505140164Sglebius 506140164Sglebius return (0); 50752419Sjulian} 50852419Sjulian 50952419Sjulian/* 510140164Sglebius * Set the hook into queueing mode (for outgoing packets), 511140164Sglebius * so that we wont deliver mbuf thru the whole graph holding 512140164Sglebius * tty locks. 51369922Sjulian */ 51469922Sjulianstatic int 51569922Sjulianngt_connect(hook_p hook) 51669922Sjulian{ 517140164Sglebius NG_HOOK_FORCE_QUEUE(NG_HOOK_PEER(hook)); 518140164Sglebius /* 519140164Sglebius * XXX: While ngt_start() is Giant-locked, queue incoming 520140164Sglebius * packets, too. Otherwise we acquire Giant holding some 521140164Sglebius * IP stack locks, e.g. divinp, and this makes WITNESS scream. 522140164Sglebius */ 523140164Sglebius NG_HOOK_FORCE_QUEUE(hook); 52469922Sjulian return (0); 52569922Sjulian} 52669922Sjulian 52769922Sjulian/* 52852419Sjulian * Disconnect the hook 52952419Sjulian */ 53052419Sjulianstatic int 53152419Sjulianngt_disconnect(hook_p hook) 53252419Sjulian{ 53370784Sjulian const sc_p sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 53452419Sjulian 53552419Sjulian if (hook != sc->hook) 53687599Sobrien panic(__func__); 537140164Sglebius 538140164Sglebius NGTLOCK(sc); 53952419Sjulian sc->hook = NULL; 540140164Sglebius NGTUNLOCK(sc); 541140164Sglebius 54252419Sjulian return (0); 54352419Sjulian} 54452419Sjulian 54552419Sjulian/* 54652419Sjulian * Remove this node. The does the netgraph portion of the shutdown. 54752419Sjulian * This should only be called indirectly from ngt_close(). 548140164Sglebius * 549140164Sglebius * tp->t_lsc is already NULL, so we should be protected from 550140164Sglebius * tty calls now. 55152419Sjulian */ 55252419Sjulianstatic int 55352419Sjulianngt_shutdown(node_p node) 55452419Sjulian{ 55570784Sjulian const sc_p sc = NG_NODE_PRIVATE(node); 55652419Sjulian 557140164Sglebius NGTLOCK(sc); 558140164Sglebius if (!(sc->flags & FLG_DIE)) { 559140164Sglebius NGTUNLOCK(sc); 56052419Sjulian return (EOPNOTSUPP); 561140164Sglebius } 562140164Sglebius NGTUNLOCK(sc); 563140164Sglebius 564140164Sglebius /* Free resources */ 565140164Sglebius _IF_DRAIN(&sc->outq); 566140164Sglebius mtx_destroy(&(sc)->outq.ifq_mtx); 567140164Sglebius m_freem(sc->m); 56870784Sjulian NG_NODE_UNREF(sc->node); 56952419Sjulian FREE(sc, M_NETGRAPH); 570140164Sglebius 57152419Sjulian return (0); 57252419Sjulian} 57352419Sjulian 57452419Sjulian/* 57552419Sjulian * Receive incoming data from netgraph system. Put it on our 57652419Sjulian * output queue and start output if necessary. 57752419Sjulian */ 57852419Sjulianstatic int 57970700Sjulianngt_rcvdata(hook_p hook, item_p item) 58052419Sjulian{ 58170784Sjulian const sc_p sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 58270700Sjulian struct mbuf *m; 583140164Sglebius int qlen; 58452419Sjulian 58552419Sjulian if (hook != sc->hook) 58687599Sobrien panic(__func__); 58770700Sjulian 58870700Sjulian NGI_GET_M(item, m); 58970700Sjulian NG_FREE_ITEM(item); 590140164Sglebius 591140164Sglebius IF_LOCK(&sc->outq); 592140164Sglebius if (_IF_QFULL(&sc->outq)) { 593140164Sglebius _IF_DROP(&sc->outq); 594140164Sglebius IF_UNLOCK(&sc->outq); 595140164Sglebius NG_FREE_M(m); 596140164Sglebius return (ENOBUFS); 597140164Sglebius } 598140164Sglebius 599140164Sglebius _IF_ENQUEUE(&sc->outq, m); 600140164Sglebius qlen = sc->outq.ifq_len; 601140164Sglebius IF_UNLOCK(&sc->outq); 602140164Sglebius 603140164Sglebius /* 604140164Sglebius * If qlen > 1, then we should already have a scheduled callout. 605140164Sglebius */ 606140164Sglebius if (qlen == 1) { 607140164Sglebius mtx_lock(&Giant); 60852419Sjulian ngt_start(sc->tp); 609140164Sglebius mtx_unlock(&Giant); 610140164Sglebius } 611140164Sglebius 612140164Sglebius return (0); 61352419Sjulian} 61452419Sjulian 61552419Sjulian/* 61652419Sjulian * Receive control message 61752419Sjulian */ 61852419Sjulianstatic int 61970700Sjulianngt_rcvmsg(node_p node, item_p item, hook_p lasthook) 62052419Sjulian{ 62170784Sjulian const sc_p sc = NG_NODE_PRIVATE(node); 622140164Sglebius struct ng_mesg *msg, *resp = NULL; 62352419Sjulian int error = 0; 62452419Sjulian 62570700Sjulian NGI_GET_MSG(item, msg); 62652419Sjulian switch (msg->header.typecookie) { 62752419Sjulian case NGM_TTY_COOKIE: 62852419Sjulian switch (msg->header.cmd) { 62952419Sjulian case NGM_TTY_SET_HOTCHAR: 63052419Sjulian { 63152419Sjulian int hotchar; 63252419Sjulian 63352419Sjulian if (msg->header.arglen != sizeof(int)) 63452419Sjulian ERROUT(EINVAL); 63552419Sjulian hotchar = *((int *) msg->data); 63652419Sjulian if (hotchar != (u_char) hotchar && hotchar != -1) 63752419Sjulian ERROUT(EINVAL); 63852419Sjulian sc->hotchar = hotchar; /* race condition is OK */ 63952419Sjulian break; 64052419Sjulian } 64152419Sjulian case NGM_TTY_GET_HOTCHAR: 64252419Sjulian NG_MKRESPONSE(resp, msg, sizeof(int), M_NOWAIT); 64352419Sjulian if (!resp) 64452419Sjulian ERROUT(ENOMEM); 64552419Sjulian /* Race condition here is OK */ 64652419Sjulian *((int *) resp->data) = sc->hotchar; 64752419Sjulian break; 64852419Sjulian default: 64952419Sjulian ERROUT(EINVAL); 65052419Sjulian } 65152419Sjulian break; 65252419Sjulian default: 65352419Sjulian ERROUT(EINVAL); 65452419Sjulian } 65552419Sjuliandone: 65670700Sjulian NG_RESPOND_MSG(error, node, item, resp); 65770700Sjulian NG_FREE_MSG(msg); 65852419Sjulian return (error); 65952419Sjulian} 66052419Sjulian 66152419Sjulian/****************************************************************** 66252419Sjulian INITIALIZATION 66352419Sjulian******************************************************************/ 66452419Sjulian 66552419Sjulian/* 66652419Sjulian * Handle loading and unloading for this node type 66752419Sjulian */ 66852419Sjulianstatic int 66952419Sjulianngt_mod_event(module_t mod, int event, void *data) 67052419Sjulian{ 671140164Sglebius int error = 0; 67252419Sjulian 67352419Sjulian switch (event) { 67452419Sjulian case MOD_LOAD: 67552419Sjulian 67652419Sjulian /* Register line discipline */ 677140164Sglebius mtx_lock(&Giant); 67852441Sjulian if ((ngt_ldisc = ldisc_register(NETGRAPHDISC, &ngt_disc)) < 0) { 679140164Sglebius mtx_unlock(&Giant); 68052419Sjulian log(LOG_ERR, "%s: can't register line discipline", 68187599Sobrien __func__); 68252419Sjulian return (EIO); 68352419Sjulian } 684140164Sglebius mtx_unlock(&Giant); 68552419Sjulian break; 68652419Sjulian 68752419Sjulian case MOD_UNLOAD: 68852419Sjulian 68952419Sjulian /* Unregister line discipline */ 690140164Sglebius mtx_lock(&Giant); 69152419Sjulian ldisc_deregister(ngt_ldisc); 692140164Sglebius mtx_unlock(&Giant); 69352419Sjulian break; 69452419Sjulian 69552419Sjulian default: 69652419Sjulian error = EOPNOTSUPP; 69752419Sjulian break; 69852419Sjulian } 69952419Sjulian return (error); 70052419Sjulian} 701