X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/2d21ac55c334faf3a56e5634905ed6987fc787d4..c6bf4f310a33a9262d455ea4d3f0630b1255e3fe:/bsd/kern/tty.c diff --git a/bsd/kern/tty.c b/bsd/kern/tty.c index 59205429a..814898803 100644 --- a/bsd/kern/tty.c +++ b/bsd/kern/tty.c @@ -1,8 +1,8 @@ /* - * Copyright (c) 1997-2007 Apple Inc. All rights reserved. + * Copyright (c) 1997-2019 Apple Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ - * + * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in @@ -11,10 +11,10 @@ * unlawful or unlicensed copies of an Apple operating system, or to * circumvent, violate, or enable the circumvention or violation of, any * terms of an Apple operating system software license agreement. - * + * * Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this file. - * + * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, @@ -22,7 +22,7 @@ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. - * + * * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ /*- @@ -92,16 +92,16 @@ * only when _all_ openers leave open(). */ #include -#define TTYDEFCHARS 1 +#define TTYDEFCHARS 1 #include -#undef TTYDEFCHARS +#undef TTYDEFCHARS #include #include #include #include #include #include -#include +#include #include #include #include @@ -112,19 +112,28 @@ #include #include -#include /* averunnable */ - -static int ttnread(struct tty *tp); -static void ttyecho(int c, struct tty *tp); -static int ttyoutput(int c, struct tty *tp); -static void ttypend(struct tty *tp); -static void ttyretype(struct tty *tp); -static void ttyrub(int c, struct tty *tp); -static void ttyrubo(struct tty *tp, int count); -static void ttystop(struct tty *tp, int rw); -static void ttyunblock(struct tty *tp); -static int ttywflush(struct tty *tp); -static int proc_compare(proc_t p1, proc_t p2); +#include /* averunnable */ +#include +#include + +static lck_grp_t *tty_lck_grp; +static lck_grp_attr_t *tty_lck_grp_attr; +static lck_attr_t *tty_lck_attr; + +__private_extern__ int ttnread(struct tty *tp); +static void ttyecho(int c, struct tty *tp); +static int ttyoutput(int c, struct tty *tp); +static void ttypend(struct tty *tp); +static void ttyretype(struct tty *tp); +static void ttyrub(int c, struct tty *tp); +static void ttyrubo(struct tty *tp, int count); +static void ttystop(struct tty *tp, int rw); +static void ttyunblock(struct tty *tp); +static int ttywflush(struct tty *tp); +static int proc_compare(proc_t p1, proc_t p2); + +void ttyhold(struct tty *tp); +static void ttydeallocate(struct tty *tp); static int isctty(proc_t p, struct tty *tp); static int isctty_sp(proc_t p, struct tty *tp, struct session *sessp); @@ -136,89 +145,89 @@ static int isctty_sp(proc_t p, struct tty *tp, struct session *sessp); * are 0 then the character needs no special processing on output; classes * other than 0 might be translated or (not currently) require delays. */ -#define E 0x00 /* Even parity. */ -#define O 0x80 /* Odd parity. */ -#define PARITY(c) (char_type[c] & O) +#define E 0x00 /* Even parity. */ +#define O 0x80 /* Odd parity. */ +#define PARITY(c) (char_type[c] & O) -#define ALPHA 0x40 /* Alpha or underscore. */ -#define ISALPHA(c) (char_type[(c) & TTY_CHARMASK] & ALPHA) +#define ALPHA 0x40 /* Alpha or underscore. */ +#define ISALPHA(c) (char_type[(c) & TTY_CHARMASK] & ALPHA) -#define CCLASSMASK 0x3f -#define CCLASS(c) (char_type[c] & CCLASSMASK) +#define CCLASSMASK 0x3f +#define CCLASS(c) (char_type[c] & CCLASSMASK) /* 0b10xxxxxx is the mask for UTF-8 continuations */ -#define CCONT(c) ((c & 0xc0) == 0x80) +#define CCONT(c) ((c & 0xc0) == 0x80) -#define BS BACKSPACE -#define CC CONTROL -#define CR RETURN -#define NA ORDINARY | ALPHA -#define NL NEWLINE -#define NO ORDINARY -#define TB TAB -#define VT VTAB +#define BS BACKSPACE +#define CC CONTROL +#define CR RETURN +#define NA ORDINARY | ALPHA +#define NL NEWLINE +#define NO ORDINARY +#define TB TAB +#define VT VTAB static u_char const char_type[] = { - E|CC, O|CC, O|CC, E|CC, O|CC, E|CC, E|CC, O|CC, /* nul - bel */ - O|BS, E|TB, E|NL, O|CC, E|VT, O|CR, O|CC, E|CC, /* bs - si */ - O|CC, E|CC, E|CC, O|CC, E|CC, O|CC, O|CC, E|CC, /* dle - etb */ - E|CC, O|CC, O|CC, E|CC, O|CC, E|CC, E|CC, O|CC, /* can - us */ - O|NO, E|NO, E|NO, O|NO, E|NO, O|NO, O|NO, E|NO, /* sp - ' */ - E|NO, O|NO, O|NO, E|NO, O|NO, E|NO, E|NO, O|NO, /* ( - / */ - E|NA, O|NA, O|NA, E|NA, O|NA, E|NA, E|NA, O|NA, /* 0 - 7 */ - O|NA, E|NA, E|NO, O|NO, E|NO, O|NO, O|NO, E|NO, /* 8 - ? */ - O|NO, E|NA, E|NA, O|NA, E|NA, O|NA, O|NA, E|NA, /* @ - G */ - E|NA, O|NA, O|NA, E|NA, O|NA, E|NA, E|NA, O|NA, /* H - O */ - E|NA, O|NA, O|NA, E|NA, O|NA, E|NA, E|NA, O|NA, /* P - W */ - O|NA, E|NA, E|NA, O|NO, E|NO, O|NO, O|NO, O|NA, /* X - _ */ - E|NO, O|NA, O|NA, E|NA, O|NA, E|NA, E|NA, O|NA, /* ` - g */ - O|NA, E|NA, E|NA, O|NA, E|NA, O|NA, O|NA, E|NA, /* h - o */ - O|NA, E|NA, E|NA, O|NA, E|NA, O|NA, O|NA, E|NA, /* p - w */ - E|NA, O|NA, O|NA, E|NO, O|NO, E|NO, E|NO, O|CC, /* x - del */ + E | CC, O | CC, O | CC, E | CC, O | CC, E | CC, E | CC, O | CC, /* nul - bel */ + O | BS, E | TB, E | NL, O | CC, E | VT, O | CR, O | CC, E | CC, /* bs - si */ + O | CC, E | CC, E | CC, O | CC, E | CC, O | CC, O | CC, E | CC, /* dle - etb */ + E | CC, O | CC, O | CC, E | CC, O | CC, E | CC, E | CC, O | CC, /* can - us */ + O | NO, E | NO, E | NO, O | NO, E | NO, O | NO, O | NO, E | NO, /* sp - ' */ + E | NO, O | NO, O | NO, E | NO, O | NO, E | NO, E | NO, O | NO, /* ( - / */ + E | NA, O | NA, O | NA, E | NA, O | NA, E | NA, E | NA, O | NA, /* 0 - 7 */ + O | NA, E | NA, E | NO, O | NO, E | NO, O | NO, O | NO, E | NO, /* 8 - ? */ + O | NO, E | NA, E | NA, O | NA, E | NA, O | NA, O | NA, E | NA, /* @ - G */ + E | NA, O | NA, O | NA, E | NA, O | NA, E | NA, E | NA, O | NA, /* H - O */ + E | NA, O | NA, O | NA, E | NA, O | NA, E | NA, E | NA, O | NA, /* P - W */ + O | NA, E | NA, E | NA, O | NO, E | NO, O | NO, O | NO, O | NA, /* X - _ */ + E | NO, O | NA, O | NA, E | NA, O | NA, E | NA, E | NA, O | NA, /* ` - g */ + O | NA, E | NA, E | NA, O | NA, E | NA, O | NA, O | NA, E | NA, /* h - o */ + O | NA, E | NA, E | NA, O | NA, E | NA, O | NA, O | NA, E | NA, /* p - w */ + E | NA, O | NA, O | NA, E | NO, O | NO, E | NO, E | NO, O | CC, /* x - del */ /* * Meta chars; should be settable per character set; * for now, treat them all as normal characters. */ - NA, NA, NA, NA, NA, NA, NA, NA, - NA, NA, NA, NA, NA, NA, NA, NA, - NA, NA, NA, NA, NA, NA, NA, NA, - NA, NA, NA, NA, NA, NA, NA, NA, - NA, NA, NA, NA, NA, NA, NA, NA, - NA, NA, NA, NA, NA, NA, NA, NA, - NA, NA, NA, NA, NA, NA, NA, NA, - NA, NA, NA, NA, NA, NA, NA, NA, - NA, NA, NA, NA, NA, NA, NA, NA, - NA, NA, NA, NA, NA, NA, NA, NA, - NA, NA, NA, NA, NA, NA, NA, NA, - NA, NA, NA, NA, NA, NA, NA, NA, - NA, NA, NA, NA, NA, NA, NA, NA, - NA, NA, NA, NA, NA, NA, NA, NA, - NA, NA, NA, NA, NA, NA, NA, NA, - NA, NA, NA, NA, NA, NA, NA, NA, + NA, NA, NA, NA, NA, NA, NA, NA, + NA, NA, NA, NA, NA, NA, NA, NA, + NA, NA, NA, NA, NA, NA, NA, NA, + NA, NA, NA, NA, NA, NA, NA, NA, + NA, NA, NA, NA, NA, NA, NA, NA, + NA, NA, NA, NA, NA, NA, NA, NA, + NA, NA, NA, NA, NA, NA, NA, NA, + NA, NA, NA, NA, NA, NA, NA, NA, + NA, NA, NA, NA, NA, NA, NA, NA, + NA, NA, NA, NA, NA, NA, NA, NA, + NA, NA, NA, NA, NA, NA, NA, NA, + NA, NA, NA, NA, NA, NA, NA, NA, + NA, NA, NA, NA, NA, NA, NA, NA, + NA, NA, NA, NA, NA, NA, NA, NA, + NA, NA, NA, NA, NA, NA, NA, NA, + NA, NA, NA, NA, NA, NA, NA, NA, }; -#undef BS -#undef CC -#undef CR -#undef NA -#undef NL -#undef NO -#undef TB -#undef VT +#undef BS +#undef CC +#undef CR +#undef NA +#undef NL +#undef NO +#undef TB +#undef VT /* Macros to clear/set/test flags. */ -#define SET(t, f) (t) |= (f) -#define CLR(t, f) (t) &= ~(f) -#define ISSET(t, f) ((t) & (f)) +#define SET(t, f) (t) |= (f) +#define CLR(t, f) (t) &= ~(f) +#define ISSET(t, f) ((t) & (f)) /* * Input control starts when we would not be able to fit the maximum * contents of the ping-pong buffers and finishes when we would be able * to fit that much plus 1/8 more. */ -#define I_HIGH_WATER (TTYHOG - 2 * 256) /* XXX */ -#define I_LOW_WATER ((TTYHOG - 2 * 256) * 7 / 8) /* XXX */ +#define I_HIGH_WATER (TTYHOG - 2 * 256) /* XXX */ +#define I_LOW_WATER ((TTYHOG - 2 * 256) * 7 / 8) /* XXX */ static void -termios32to64(struct termios *in, struct user_termios *out) +termios32to64(struct termios32 *in, struct user_termios *out) { out->c_iflag = (user_tcflag_t)in->c_iflag; out->c_oflag = (user_tcflag_t)in->c_oflag; @@ -233,7 +242,7 @@ termios32to64(struct termios *in, struct user_termios *out) } static void -termios64to32(struct user_termios *in, struct termios *out) +termios64to32(struct user_termios *in, struct termios32 *out) { out->c_iflag = (tcflag_t)in->c_iflag; out->c_oflag = (tcflag_t)in->c_oflag; @@ -249,86 +258,113 @@ termios64to32(struct user_termios *in, struct termios *out) /* + * tty_init + * + * Initialize the tty line discipline subsystem. + * + * Parameters: void + * + * Returns: void + * + * Locks: No ttys can be allocated and no tty locks can be used + * until after this function is called + * + * Notes: The intent of this is to set up a log group attribute, + * lock group, and loc atribute for subsequent per-tty locks. + * This function is called early in bsd_init(), prior to the + * console device initialization. + */ +void +tty_init(void) +{ + tty_lck_grp_attr = lck_grp_attr_alloc_init(); + tty_lck_grp = lck_grp_alloc_init("tty", tty_lck_grp_attr); + tty_lck_attr = lck_attr_alloc_init(); +} + + +/* + * tty_lock + * + * Lock the requested tty structure. + * + * Parameters: tp The tty we want to lock + * + * Returns: void + * + * Locks: On return, tp is locked + */ +void +tty_lock(struct tty *tp) +{ + TTY_LOCK_NOTOWNED(tp); /* debug assert */ + lck_mtx_lock(&tp->t_lock); +} + + +/* + * tty_unlock + * + * Unlock the requested tty structure. + * + * Parameters: tp The tty we want to unlock + * + * Returns: void + * + * Locks: On return, tp is unlocked + */ +void +tty_unlock(struct tty *tp) +{ + TTY_LOCK_OWNED(tp); /* debug assert */ + lck_mtx_unlock(&tp->t_lock); +} + +/* + * ttyopen (LDISC) + * * Initial open of tty, or (re)entry to standard tty line discipline. + * + * Locks: Assumes tty_lock() is held prior to calling. */ int ttyopen(dev_t device, struct tty *tp) { - boolean_t funnel_state; - proc_t p = current_proc(); - struct pgrp * pg, * oldpg; - struct session *sessp, *oldsess; - - funnel_state = thread_funnel_set(kernel_flock, TRUE); + TTY_LOCK_OWNED(tp); /* debug assert */ tp->t_dev = device; if (!ISSET(tp->t_state, TS_ISOPEN)) { SET(tp->t_state, TS_ISOPEN); if (ISSET(tp->t_cflag, CLOCAL)) { - SET(tp->t_state, TS_CONNECTED); } + SET(tp->t_state, TS_CONNECTED); + } bzero(&tp->t_winsize, sizeof(tp->t_winsize)); } - pg = proc_pgrp(p); - sessp = proc_session(p); - - /* - * First tty open affter setsid() call makes this tty its controlling - * tty, if the tty does not already have a session associated with it. - * Only do this if the process - */ - if (SESS_LEADER(p, sessp) && /* process is session leader */ - sessp->s_ttyvp == NULL && /* but has no controlling tty */ - tp->t_session == NULL ) { /* and tty not controlling */ - session_lock(sessp); - if ((sessp->s_flags & S_NOCTTY) == 0) { /* and no O_NOCTTY */ - /* Hold on to the reference */ - sessp->s_ttyp = tp; - OSBitOrAtomic(P_CONTROLT, (UInt32 *)&p->p_flag); - session_unlock(sessp); - proc_list_lock(); - oldpg = tp->t_pgrp; - oldsess = tp->t_session; - if (oldsess != SESSION_NULL) - oldsess->s_ttypgrpid = NO_PID; - tp->t_session = sessp; - tp->t_pgrp = pg; - sessp->s_ttypgrpid = pg->pg_id; - proc_list_unlock(); - if (oldpg != PGRP_NULL) - pg_rele(oldpg); - if (oldsess != SESSION_NULL) - session_rele(oldsess); - goto out; - } - session_unlock(sessp); - } - - if (sessp != SESSION_NULL) - session_rele(sessp); - if (pg != PGRP_NULL) - pg_rele(pg); - -out: - thread_funnel_set(kernel_flock, funnel_state); - - return (0); + return 0; } /* + * ttyclose + * * Handle close() on a tty line: flush and set to initial state, * bumping generation number so that pending read/write calls * can detect recycling of the tty. * XXX our caller should have done `spltty(); l_close(); ttyclose();' * and l_close() should have flushed, but we repeat the spltty() and * the flush in case there are buggy callers. + * + * Locks: Assumes tty_lock() is held prior to calling. */ int ttyclose(struct tty *tp) { struct pgrp * oldpg; struct session * oldsessp; + struct knote *kn; + + TTY_LOCK_OWNED(tp); /* debug assert */ if (constty == tp) { constty = NULL; @@ -336,10 +372,10 @@ ttyclose(struct tty *tp) /* * Closing current console tty; disable printing of console - * messages at bottom-level driver. + * messages at bottom-level driver. */ (*cdevsw[major(tp->t_dev)].d_ioctl) - (tp->t_dev, KMIOCDISABLCONS, NULL, 0, current_proc()); + (tp->t_dev, KMIOCDISABLCONS, NULL, 0, current_proc()); } ttyflush(tp, FREAD | FWRITE); @@ -351,50 +387,73 @@ ttyclose(struct tty *tp) oldsessp = tp->t_session; tp->t_pgrp = NULL; tp->t_session = NULL; - if (oldsessp != SESSION_NULL) + if (oldsessp != SESSION_NULL) { oldsessp->s_ttypgrpid = NO_PID; + } proc_list_unlock(); /* drop the reference on prev session and pgrp */ - if (oldsessp != SESSION_NULL) + /* SAFE: All callers drop the lock on return */ + tty_unlock(tp); + if (oldsessp != SESSION_NULL) { session_rele(oldsessp); - if (oldpg != PGRP_NULL) + } + if (oldpg != PGRP_NULL) { pg_rele(oldpg); + } + tty_lock(tp); tp->t_state = 0; + SLIST_FOREACH(kn, &tp->t_wsel.si_note, kn_selnext) { + KNOTE_DETACH(&tp->t_wsel.si_note, kn); + } selthreadclear(&tp->t_wsel); + SLIST_FOREACH(kn, &tp->t_rsel.si_note, kn_selnext) { + KNOTE_DETACH(&tp->t_rsel.si_note, kn); + } selthreadclear(&tp->t_rsel); - return (0); + + return 0; } -#define FLUSHQ(q) { \ - if ((q)->c_cc) \ - ndflush(q, (q)->c_cc); \ +#define FLUSHQ(q) { \ + if ((q)->c_cc) \ + ndflush(q, (q)->c_cc); \ } /* Is 'c' a line delimiter ("break" character)? */ -#define TTBREAKC(c, lflag) \ - ((c) == '\n' || (((c) == cc[VEOF] || \ - (c) == cc[VEOL] || ((c) == cc[VEOL2] && lflag & IEXTEN)) && \ +#define TTBREAKC(c, lflag) \ + ((c) == '\n' || (((c) == cc[VEOF] || \ + (c) == cc[VEOL] || ((c) == cc[VEOL2] && lflag & IEXTEN)) && \ (c) != _POSIX_VDISABLE)) /* + * ttyinput (LDISC) + * * Process input of a single character received on a tty. + * + * Parameters: c The character received + * tp The tty on which it was received + * + * Returns: . + * + * Locks: Assumes tty_lock() is held prior to calling. */ int ttyinput(int c, struct tty *tp) { tcflag_t iflag, lflag; cc_t *cc; - int i, err, retval; - boolean_t funnel_state; + int i, err; + int retval = 0; /* default return value */ + + TTY_LOCK_OWNED(tp); /* debug assert */ - funnel_state = thread_funnel_set(kernel_flock, TRUE); - /* * If input is pending take it first. */ lflag = tp->t_lflag; - if (ISSET(lflag, PENDIN)) + if (ISSET(lflag, PENDIN)) { ttypend(tp); + } /* * Gather stats. */ @@ -417,8 +476,9 @@ ttyinput(int c, struct tty *tp) if (tp->t_rawq.c_cc + tp->t_canq.c_cc > I_HIGH_WATER - 3 && (!ISSET(lflag, ICANON) || tp->t_canq.c_cc != 0) && (ISSET(tp->t_cflag, CRTS_IFLOW) || ISSET(iflag, IXOFF)) && - !ISSET(tp->t_state, TS_TBLOCK)) + !ISSET(tp->t_state, TS_TBLOCK)) { ttyblock(tp); + } /* Handle exceptional conditions (break, parity, framing). */ cc = tp->t_cc; @@ -427,38 +487,42 @@ ttyinput(int c, struct tty *tp) CLR(c, TTY_ERRORMASK); if (ISSET(err, TTY_BI)) { if (ISSET(iflag, IGNBRK)) { - thread_funnel_set(kernel_flock, funnel_state); - return (0); - } + goto out; + } if (ISSET(iflag, BRKINT)) { ttyflush(tp, FREAD | FWRITE); + /* SAFE: All callers drop the lock on return */ + tty_unlock(tp); tty_pgsignal(tp, SIGINT, 1); + tty_lock(tp); goto endcase; } - if (ISSET(iflag, PARMRK)) + if (ISSET(iflag, PARMRK)) { goto parmrk; + } } else if ((ISSET(err, TTY_PE) && ISSET(iflag, INPCK)) - || ISSET(err, TTY_FE)) { + || ISSET(err, TTY_FE)) { if (ISSET(iflag, IGNPAR)) { - thread_funnel_set(kernel_flock, funnel_state); - return (0); - } - else if (ISSET(iflag, PARMRK)) { + goto out; + } else if (ISSET(iflag, PARMRK)) { parmrk: if (tp->t_rawq.c_cc + tp->t_canq.c_cc > - MAX_INPUT - 3) + MAX_INPUT - 3) { goto input_overflow; + } (void)putc(0377 | TTY_QUOTE, &tp->t_rawq); (void)putc(0 | TTY_QUOTE, &tp->t_rawq); (void)putc(c | TTY_QUOTE, &tp->t_rawq); goto endcase; - } else + } else { c = 0; + } } } - if (!ISSET(tp->t_state, TS_TYPEN) && ISSET(iflag, ISTRIP)) + if (!ISSET(tp->t_state, TS_TYPEN) && ISSET(iflag, ISTRIP)) { CLR(c, 0x80); + } if (!ISSET(lflag, EXTPROC)) { /* * Check for literal nexting very first @@ -485,20 +549,22 @@ parmrk: if (ISSET(lflag, ECHOE)) { (void)ttyoutput('^', tp); (void)ttyoutput('\b', tp); - } else + } else { ttyecho(c, tp); + } } SET(tp->t_state, TS_LNCH); goto endcase; } if (CCEQ(cc[VDISCARD], c)) { - if (ISSET(lflag, FLUSHO)) + if (ISSET(lflag, FLUSHO)) { CLR(tp->t_lflag, FLUSHO); - else { + } else { ttyflush(tp, FWRITE); ttyecho(c, tp); - if (tp->t_rawq.c_cc + tp->t_canq.c_cc) + if (tp->t_rawq.c_cc + tp->t_canq.c_cc) { ttyretype(tp); + } SET(tp->t_lflag, FLUSHO); } goto startoutput; @@ -509,18 +575,34 @@ parmrk: */ if (ISSET(lflag, ISIG)) { if (CCEQ(cc[VINTR], c) || CCEQ(cc[VQUIT], c)) { - if (!ISSET(lflag, NOFLSH)) + if (!ISSET(lflag, NOFLSH)) { ttyflush(tp, FREAD | FWRITE); + } ttyecho(c, tp); + /* + * SAFE: All callers drop the lock on return; + * SAFE: if we lose a threaded race on change + * SAFE: of the interrupt character, we could + * SAFE: have lost that race anyway due to the + * SAFE: scheduler executing threads in + * SAFE: priority order rather than "last + * SAFE: active thread" order (FEATURE). + */ + tty_unlock(tp); tty_pgsignal(tp, CCEQ(cc[VINTR], c) ? SIGINT : SIGQUIT, 1); + tty_lock(tp); goto endcase; } if (CCEQ(cc[VSUSP], c)) { - if (!ISSET(lflag, NOFLSH)) + if (!ISSET(lflag, NOFLSH)) { ttyflush(tp, FREAD); + } ttyecho(c, tp); + /* SAFE: All callers drop the lock on return */ + tty_unlock(tp); tty_pgsignal(tp, SIGTSTP, 1); + tty_lock(tp); goto endcase; } } @@ -531,34 +613,33 @@ parmrk: if (CCEQ(cc[VSTOP], c)) { if (!ISSET(tp->t_state, TS_TTSTOP)) { SET(tp->t_state, TS_TTSTOP); - ttystop(tp, 0); - thread_funnel_set(kernel_flock, funnel_state); - return (0); + ttystop(tp, 0); + goto out; } if (!CCEQ(cc[VSTART], c)) { - thread_funnel_set(kernel_flock, funnel_state); - return (0); - } + goto out; + } /* * if VSTART == VSTOP then toggle */ goto endcase; } - if (CCEQ(cc[VSTART], c)) + if (CCEQ(cc[VSTART], c)) { goto restartoutput; + } } /* * IGNCR, ICRNL, & INLCR */ if (c == '\r') { if (ISSET(iflag, IGNCR)) { - thread_funnel_set(kernel_flock, funnel_state); - return (0); - } - else if (ISSET(iflag, ICRNL)) + goto out; + } else if (ISSET(iflag, ICRNL)) { c = '\n'; - } else if (c == '\n' && ISSET(iflag, INLCR)) + } + } else if (c == '\n' && ISSET(iflag, INLCR)) { c = '\r'; + } } if (!ISSET(tp->t_lflag, EXTPROC) && ISSET(lflag, ICANON)) { /* @@ -573,7 +654,7 @@ parmrk: if (ISSET(iflag, IUTF8)) { do { ttyrub((c = unputc(&tp->t_rawq)), tp); - } while(tp->t_rawq.c_cc && CCONT(c)); + } while (tp->t_rawq.c_cc && CCONT(c)); } else { ttyrub(unputc(&tp->t_rawq), tp); } @@ -586,14 +667,16 @@ parmrk: if (CCEQ(cc[VKILL], c)) { if (ISSET(lflag, ECHOKE) && tp->t_rawq.c_cc == tp->t_rocount && - !ISSET(lflag, ECHOPRT)) - while (tp->t_rawq.c_cc) + !ISSET(lflag, ECHOPRT)) { + while (tp->t_rawq.c_cc) { ttyrub(unputc(&tp->t_rawq), tp); - else { + } + } else { ttyecho(c, tp); if (ISSET(lflag, ECHOK) || - ISSET(lflag, ECHOKE)) + ISSET(lflag, ECHOKE)) { ttyecho('\n', tp); + } FLUSHQ(&tp->t_rawq); tp->t_rocount = 0; } @@ -609,18 +692,21 @@ parmrk: /* * erase whitespace */ - while ((c = unputc(&tp->t_rawq)) == ' ' || c == '\t') + while ((c = unputc(&tp->t_rawq)) == ' ' || c == '\t') { ttyrub(c, tp); - if (c == -1) + } + if (c == -1) { goto endcase; + } /* * erase last char of word and remember the * next chars type (for ALTWERASE) */ ttyrub(c, tp); c = unputc(&tp->t_rawq); - if (c == -1) + if (c == -1) { goto endcase; + } if (c == ' ' || c == '\t') { (void)putc(c, &tp->t_rawq); goto endcase; @@ -632,8 +718,9 @@ parmrk: do { ttyrub(c, tp); c = unputc(&tp->t_rawq); - if (c == -1) + if (c == -1) { goto endcase; + } } while (c != ' ' && c != '\t' && (!ISSET(lflag, ALTWERASE) || ISALPHA(c) == ctype)); (void)putc(c, &tp->t_rawq); @@ -650,10 +737,15 @@ parmrk: * ^T - kernel info and generate SIGINFO */ if (CCEQ(cc[VSTATUS], c) && ISSET(lflag, IEXTEN)) { - if (ISSET(lflag, ISIG)) + if (ISSET(lflag, ISIG)) { + /* SAFE: All callers drop the lock on return */ + tty_unlock(tp); tty_pgsignal(tp, SIGINFO, 1); - if (!ISSET(lflag, NOKERNINFO)) - ttyinfo(tp); + tty_lock(tp); + } + if (!ISSET(lflag, NOKERNINFO)) { + ttyinfo_locked(tp); + } goto endcase; } } @@ -663,15 +755,17 @@ parmrk: if (tp->t_rawq.c_cc + tp->t_canq.c_cc >= MAX_INPUT) { input_overflow: if (ISSET(iflag, IMAXBEL)) { - if (tp->t_outq.c_cc < tp->t_hiwat) + if (tp->t_outq.c_cc < tp->t_hiwat) { (void)ttyoutput(CTRL('g'), tp); + } } goto endcase; } - if ( c == 0377 && ISSET(iflag, PARMRK) && !ISSET(iflag, ISTRIP) - && ISSET(iflag, IGNBRK|IGNPAR) != (IGNBRK|IGNPAR)) + if (c == 0377 && ISSET(iflag, PARMRK) && !ISSET(iflag, ISTRIP) + && ISSET(iflag, IGNBRK | IGNPAR) != (IGNBRK | IGNPAR)) { (void)putc(0377 | TTY_QUOTE, &tp->t_rawq); + } /* * Put data char in q for user and @@ -687,8 +781,9 @@ input_overflow: tp->t_rocount = 0; catq(&tp->t_rawq, &tp->t_canq); ttwakeup(tp); - } else if (tp->t_rocount++ == 0) + } else if (tp->t_rocount++ == 0) { tp->t_rocol = tp->t_column; + } if (ISSET(tp->t_state, TS_ERASE)) { /* * end of prterase \.../ @@ -709,29 +804,44 @@ input_overflow: } } } + endcase: /* * IXANY means allow any character to restart output. */ if (ISSET(tp->t_state, TS_TTSTOP) && !ISSET(iflag, IXANY) && cc[VSTART] != cc[VSTOP]) { - thread_funnel_set(kernel_flock, funnel_state); - return (0); - } + goto out; + } + restartoutput: CLR(tp->t_lflag, FLUSHO); CLR(tp->t_state, TS_TTSTOP); + startoutput: - retval = ttstart(tp); - thread_funnel_set(kernel_flock, funnel_state); - return (retval); + /* Start the output */ + retval = ttstart(tp); + +out: + return retval; } + /* + * ttyoutput + * * Output a single character on a tty, doing output processing * as needed (expanding tabs, newline processing, etc.). - * Returns < 0 if succeeds, otherwise returns char to resend. - * Must be recursive. + * + * Parameters: c The character to output + * tp The tty on which to output on the tty + * + * Returns: < 0 Success + * >= 0 Character to resend (failure) + * + * Locks: Assumes tp is locked on entry, remains locked on exit + * + * Notes: Must be recursive. */ static int ttyoutput(int c, struct tty *tp) @@ -739,15 +849,19 @@ ttyoutput(int c, struct tty *tp) tcflag_t oflag; int col; + TTY_LOCK_OWNED(tp); /* debug assert */ + oflag = tp->t_oflag; if (!ISSET(oflag, OPOST)) { - if (ISSET(tp->t_lflag, FLUSHO)) - return (-1); - if (putc(c, &tp->t_outq)) - return (c); + if (ISSET(tp->t_lflag, FLUSHO)) { + return -1; + } + if (putc(c, &tp->t_outq)) { + return c; + } tk_nout++; tp->t_outcc++; - return (-1); + return -1; } /* * Do tab expansion if OXTABS is set. Special case if we external @@ -765,10 +879,11 @@ ttyoutput(int c, struct tty *tp) tp->t_outcc += c; } tp->t_column += c; - return (c == col ? -1 : '\t'); + return c == col ? -1 : '\t'; + } + if (c == CEOT && ISSET(oflag, ONOEOT)) { + return -1; } - if (c == CEOT && ISSET(oflag, ONOEOT)) - return (-1); /* * Newline translation: if ONLCR is set, @@ -777,25 +892,30 @@ ttyoutput(int c, struct tty *tp) if (c == '\n' && ISSET(tp->t_oflag, ONLCR)) { tk_nout++; tp->t_outcc++; - if (putc('\r', &tp->t_outq)) - return (c); - } - /* If OCRNL is set, translate "\r" into "\n". */ - else if (c == '\r' && ISSET(tp->t_oflag, OCRNL)) - c = '\n'; - /* If ONOCR is set, don't transmit CRs when on column 0. */ - else if (c == '\r' && ISSET(tp->t_oflag, ONOCR) && tp->t_column == 0) - return (-1); + if (putc('\r', &tp->t_outq)) { + return c; + } + } + /* If OCRNL is set, translate "\r" into "\n". */ + else if (c == '\r' && ISSET(tp->t_oflag, OCRNL)) { + c = '\n'; + } + /* If ONOCR is set, don't transmit CRs when on column 0. */ + else if (c == '\r' && ISSET(tp->t_oflag, ONOCR) && tp->t_column == 0) { + return -1; + } tk_nout++; tp->t_outcc++; - if (!ISSET(tp->t_lflag, FLUSHO) && putc(c, &tp->t_outq)) - return (c); + if (!ISSET(tp->t_lflag, FLUSHO) && putc(c, &tp->t_outq)) { + return c; + } col = tp->t_column; switch (CCLASS(c)) { case BACKSPACE: - if (col > 0) + if (col > 0) { --col; + } break; case CONTROL: break; @@ -811,23 +931,145 @@ ttyoutput(int c, struct tty *tp) break; } tp->t_column = col; - return (-1); + return -1; +} + +/* + * Sets the tty state to not allow any more changes of foreground process + * group. This is required to be done so that a subsequent revoke on a vnode + * is able to always successfully complete. + * + * Locks : Assumes tty_lock held on entry + */ +void +ttysetpgrphup(struct tty *tp) +{ + TTY_LOCK_OWNED(tp); /* debug assert */ + SET(tp->t_state, TS_PGRPHUP); + /* + * Also wake up sleeping readers which may or may not belong to the + * current foreground process group. + * + * This forces any non-fg readers (which entered read when + * that process group was in the fg) to return with EIO (if they're + * catching SIGTTIN or with SIGTTIN). The ones which do belong to the fg + * process group will promptly go back to sleep and get a SIGHUP shortly + * This would normally happen as part of the close in revoke but if + * there is a sleeping reader from a non-fg process group we never get + * to the close because the sleeping reader holds an iocount on the + * vnode of the terminal which is going to get revoked->reclaimed. + */ + wakeup(TSA_HUP_OR_INPUT(tp)); +} + +/* + * Locks : Assumes tty lock held on entry + */ +void +ttyclrpgrphup(struct tty *tp) +{ + TTY_LOCK_OWNED(tp); /* debug assert */ + CLR(tp->t_state, TS_PGRPHUP); +} + +/* + * ttioctl + * + * Identical to ttioctl_locked, only the lock is not held + * + * Parameters: + * + * Returns: + * + * Locks: This function assumes the tty_lock() is not held on entry; + * it takes the lock, and releases it before returning. + * + * Notes: This is supported to ensure the line discipline interfaces + * all have the same locking semantics. + * + * This function is called from + */ +int +ttioctl(struct tty *tp, u_long cmd, caddr_t data, int flag, proc_t p) +{ + int retval; + + tty_lock(tp); + retval = ttioctl_locked(tp, cmd, data, flag, p); + tty_unlock(tp); + + return retval; } + /* - * Ioctls for all tty devices. Called after line-discipline specific ioctl - * has been called to do discipline-specific functions and/or reject any - * of these ioctl commands. + * ttioctl_locked + * + * Ioctls for all tty devices. + * + * Parameters: tp Tty on which ioctl() is being called + * cmd ioctl() command parameter + * data ioctl() data argument (if any) + * flag fileglob open modes from fcntl.h; + * if called internally, this is usually + * set to 0, rather than something useful + * p Process context for the call; if the + * call is proxied to a worker thread, + * this will not be the current process!!! + * + * Returns: 0 Success + * EIO I/O error (no process group, job + * control, etc.) + * EINTR Interrupted by signal + * EBUSY Attempt to become the console while + * the console is busy + * ENOTTY TIOCGPGRP on a non-controlling tty + * EINVAL Invalid baud rate + * ENXIO TIOCSETD of invalid line discipline + * EPERM TIOCSTI, not root, not open for read + * EACCES TIOCSTI, not root, not your controlling + * tty + * EPERM TIOCSCTTY failed + * ENOTTY/EINVAL/EPERM TIOCSPGRP failed + * EPERM TIOCSDRAINWAIT as non-root user + * suser:EPERM Console control denied + * ttywait:EIO t_timeout too small/expired + * ttywait:ERESTART Upper layer must redrive the call; + * this is usually done by the Libc + * stub in user space + * ttywait:EINTR Interrupted (usually a signal) + * ttcompat:EINVAL + * ttcompat:ENOTTY + * ttcompat:EIOCTL + * ttcompat:ENOTTY TIOCGSID, if no session or session + * leader + * ttcompat:ENOTTY All unrecognized ioctls + * *tp->t_param:? TIOCSETA* underlying function + * *linesw[t].l_open:? TIOCSETD line discipline open failure + * + * + * Locks: This function assumes that the tty_lock() is held for the + * tp at the time of the call. The lock remains held on return. + * + * Notes: This function is called after line-discipline specific ioctl + * has been called to do discipline-specific functions and/or + * reject any of these ioctl() commands. + * + * This function calls ttcompat(), which can re-call ttioctl() + * to a depth of one (FORTRAN style mutual recursion); at some + * point, we should just in-line ttcompat() here. */ int -ttioctl(struct tty *tp, - u_long cmd, caddr_t data, int flag, - proc_t p) +ttioctl_locked(struct tty *tp, u_long cmd, caddr_t data, int flag, proc_t p) { int error = 0; + int bogusData = 1; struct uthread *ut; - struct pgrp * pg, *oldpg; - struct session *sessp, * oldsessp; + struct pgrp *pg, *oldpg; + struct session *sessp, *oldsessp; + struct tty *oldtp; + + TTY_LOCK_OWNED(tp); /* debug assert */ ut = (struct uthread *)get_bsdthread_info(current_thread()); /* If the ioctl involves modification, signal if in the background. */ @@ -838,18 +1080,17 @@ ttioctl(struct tty *tp, case TIOCFLUSH: case TIOCSTOP: case TIOCSTART: - case TIOCSETA: + case TIOCSETA_32: case TIOCSETA_64: case TIOCSETD: - case TIOCSETAF: + case TIOCSETAF_32: case TIOCSETAF_64: - case TIOCSETAW: + case TIOCSETAW_32: case TIOCSETAW_64: case TIOCSPGRP: case TIOCSTAT: case TIOCSTI: case TIOCSWINSZ: -#if COMPAT_43_TTY || defined(COMPAT_SUNOS) case TIOCLBIC: case TIOCLBIS: case TIOCLSET: @@ -858,7 +1099,6 @@ ttioctl(struct tty *tp, case TIOCSETN: case TIOCSETP: case TIOCSLTC: -#endif while (isbackground(p, tp) && (p->p_lflag & P_LPPWAIT) == 0 && (p->p_sigignore & sigmask(SIGTTOU)) == 0 && @@ -868,13 +1108,17 @@ ttioctl(struct tty *tp, error = EIO; goto out; } + /* SAFE: All callers drop the lock on return */ + tty_unlock(tp); if (pg->pg_jobc == 0) { pg_rele(pg); + tty_lock(tp); error = EIO; goto out; } pgsignal(pg, SIGTTOU, 1); pg_rele(pg); + tty_lock(tp); /* @@ -889,81 +1133,89 @@ ttioctl(struct tty *tp, break; } - switch (cmd) { /* Process the ioctl. */ - case FIOASYNC: /* set/clear async i/o */ - if (*(int *)data) + switch (cmd) { /* Process the ioctl. */ + case FIOASYNC: /* set/clear async i/o */ + if (*(int *)data) { SET(tp->t_state, TS_ASYNC); - else + } else { CLR(tp->t_state, TS_ASYNC); + } break; - case FIONBIO: /* set/clear non-blocking i/o */ - break; /* XXX: delete. */ - case FIONREAD: /* get # bytes to read */ + case FIONBIO: /* set/clear non-blocking i/o */ + break; /* XXX: delete. */ + case FIONREAD: /* get # bytes to read */ *(int *)data = ttnread(tp); break; - case TIOCEXCL: /* set exclusive use of tty */ + case TIOCEXCL: /* set exclusive use of tty */ SET(tp->t_state, TS_XCLUDE); break; - case TIOCFLUSH: { /* flush buffers */ + case TIOCFLUSH: { /* flush buffers */ int flags = *(int *)data; - if (flags == 0) + if (flags == 0) { flags = FREAD | FWRITE; - else + } else { flags &= FREAD | FWRITE; + } ttyflush(tp, flags); break; } case TIOCSCONS: { /* Set current console device to this line */ - int bogusData = 1; data = (caddr_t) &bogusData; /* No break - Fall through to BSD code */ } - case TIOCCONS: { /* become virtual console */ + case TIOCCONS: { /* become virtual console */ if (*(int *)data) { if (constty && constty != tp && ISSET(constty->t_state, TS_CONNECTED)) { error = EBUSY; goto out; } - if ( (error = suser(kauth_cred_get(), &p->p_acflag)) ) + if ((error = suser(kauth_cred_get(), &p->p_acflag))) { goto out; + } constty = tp; } else if (tp == constty) { constty = NULL; } if (constty) { - (*cdevsw[major(cons.t_dev)].d_ioctl) - (cons.t_dev, KMIOCDISABLCONS, NULL, 0, p); + (*cdevsw[major(constty->t_dev)].d_ioctl) + (constty->t_dev, KMIOCDISABLCONS, NULL, 0, p); } else { (*cdevsw[major(tp->t_dev)].d_ioctl) - (tp->t_dev, KMIOCDISABLCONS, NULL, 0, p); + (tp->t_dev, KMIOCDISABLCONS, NULL, 0, p); } break; } - case TIOCDRAIN: /* wait till output drained */ + case TIOCDRAIN: /* wait till output drained */ error = ttywait(tp); - if (error) + if (error) { goto out; - break; - case TIOCGETA: /* get termios struct */ - case TIOCGETA_64: { /* get termios struct */ - if (IS_64BIT_PROCESS(p)) { - termios32to64(&tp->t_termios, (struct user_termios *)data); - } else { - bcopy(&tp->t_termios, data, sizeof(struct termios)); } break; - } - case TIOCGETD: /* get line discipline */ + case TIOCGETA_32: /* get termios struct */ +#ifdef __LP64__ + termios64to32((struct user_termios *)&tp->t_termios, (struct termios32 *)data); +#else + bcopy(&tp->t_termios, data, sizeof(struct termios)); +#endif + break; + case TIOCGETA_64: /* get termios struct */ +#ifdef __LP64__ + bcopy(&tp->t_termios, data, sizeof(struct termios)); +#else + termios32to64((struct termios32 *)&tp->t_termios, (struct user_termios *)data); +#endif + break; + case TIOCGETD: /* get line discipline */ *(int *)data = tp->t_line; break; - case TIOCGWINSZ: /* get window size */ + case TIOCGWINSZ: /* get window size */ *(struct winsize *)data = tp->t_winsize; break; - case TIOCGPGRP: /* get pgrp of tty */ + case TIOCGPGRP: /* get pgrp of tty */ if (!isctty(p, tp)) { error = ENOTTY; goto out; @@ -971,46 +1223,56 @@ ttioctl(struct tty *tp, *(int *)data = tp->t_pgrp ? tp->t_pgrp->pg_id : NO_PID; break; #ifdef TIOCHPCL - case TIOCHPCL: /* hang up on last close */ + case TIOCHPCL: /* hang up on last close */ SET(tp->t_cflag, HUPCL); break; #endif - case TIOCNXCL: /* reset exclusive use of tty */ + case TIOCNXCL: /* reset exclusive use of tty */ CLR(tp->t_state, TS_XCLUDE); break; - case TIOCOUTQ: /* output queue size */ + case TIOCOUTQ: /* output queue size */ *(int *)data = tp->t_outq.c_cc; break; - case TIOCSETA: /* set termios struct */ + case TIOCSETA_32: /* set termios struct */ case TIOCSETA_64: - case TIOCSETAW: /* drain output, set */ + case TIOCSETAW_32: /* drain output, set */ case TIOCSETAW_64: - case TIOCSETAF: /* drn out, fls in, set */ - case TIOCSETAF_64: { /* drn out, fls in, set */ + case TIOCSETAF_32: /* drn out, fls in, set */ + case TIOCSETAF_64: + { /* drn out, fls in, set */ struct termios *t = (struct termios *)data; struct termios lcl_termios; - if (IS_64BIT_PROCESS(p)) { - termios64to32((struct user_termios *)data, &lcl_termios); +#ifdef __LP64__ + if (cmd == TIOCSETA_32 || cmd == TIOCSETAW_32 || cmd == TIOCSETAF_32) { + termios32to64((struct termios32 *)data, (struct user_termios *)&lcl_termios); + t = &lcl_termios; + } +#else + if (cmd == TIOCSETA_64 || cmd == TIOCSETAW_64 || cmd == TIOCSETAF_64) { + termios64to32((struct user_termios *)data, (struct termios32 *)&lcl_termios); t = &lcl_termios; } +#endif #if 0 - /* XXX bogus test; always false */ + /* XXX bogus test; always false */ if (t->c_ispeed < 0 || t->c_ospeed < 0) { error = EINVAL; goto out; } -#endif /* 0 - leave in; may end up being a conformance issue */ - if (t->c_ispeed == 0) +#endif /* 0 - leave in; may end up being a conformance issue */ + if (t->c_ispeed == 0) { t->c_ispeed = t->c_ospeed; - if (cmd == TIOCSETAW || cmd == TIOCSETAF || + } + if (cmd == TIOCSETAW_32 || cmd == TIOCSETAF_32 || cmd == TIOCSETAW_64 || cmd == TIOCSETAF_64) { error = ttywait(tp); if (error) { goto out; } - if (cmd == TIOCSETAF || cmd == TIOCSETAF_64) + if (cmd == TIOCSETAF_32 || cmd == TIOCSETAF_64) { ttyflush(tp, FREAD); + } } if (!ISSET(t->c_cflag, CIGNORE)) { /* @@ -1034,21 +1296,22 @@ ttioctl(struct tty *tp, ttwwakeup(tp); } if ((ISSET(tp->t_state, TS_CARR_ON) || - ISSET(t->c_cflag, CLOCAL)) && - !ISSET(tp->t_state, TS_ZOMBIE)) + ISSET(t->c_cflag, CLOCAL)) && + !ISSET(tp->t_state, TS_ZOMBIE)) { SET(tp->t_state, TS_CONNECTED); - else + } else { CLR(tp->t_state, TS_CONNECTED); + } tp->t_cflag = t->c_cflag; tp->t_ispeed = t->c_ispeed; tp->t_ospeed = t->c_ospeed; ttsetwater(tp); } if (ISSET(t->c_lflag, ICANON) != ISSET(tp->t_lflag, ICANON) && - cmd != TIOCSETAF && cmd != TIOCSETAF_64) { - if (ISSET(t->c_lflag, ICANON)) + cmd != TIOCSETAF_32 && cmd != TIOCSETAF_64) { + if (ISSET(t->c_lflag, ICANON)) { SET(tp->t_lflag, PENDIN); - else { + } else { /* * XXX we really shouldn't allow toggling * ICANON while we're in a non-termios line @@ -1056,12 +1319,12 @@ ttioctl(struct tty *tp, * panicing for a null queue. */ if (tp->t_rawq.c_cs && tp->t_canq.c_cs) { - struct clist tq; + struct clist tq; - catq(&tp->t_rawq, &tp->t_canq); - tq = tp->t_rawq; - tp->t_rawq = tp->t_canq; - tp->t_canq = tq; + catq(&tp->t_rawq, &tp->t_canq); + tq = tp->t_rawq; + tp->t_rawq = tp->t_canq; + tp->t_canq = tq; } CLR(tp->t_lflag, PENDIN); } @@ -1072,18 +1335,20 @@ ttioctl(struct tty *tp, /* * Make the EXTPROC bit read only. */ - if (ISSET(tp->t_lflag, EXTPROC)) + if (ISSET(tp->t_lflag, EXTPROC)) { SET(t->c_lflag, EXTPROC); - else + } else { CLR(t->c_lflag, EXTPROC); + } tp->t_lflag = t->c_lflag | ISSET(tp->t_lflag, PENDIN); if (t->c_cc[VMIN] != tp->t_cc[VMIN] || - t->c_cc[VTIME] != tp->t_cc[VTIME]) + t->c_cc[VTIME] != tp->t_cc[VTIME]) { ttwakeup(tp); + } bcopy(t->c_cc, tp->t_cc, sizeof(t->c_cc)); break; } - case TIOCSETD: { /* set line discipline */ + case TIOCSETD: { /* set line discipline */ int t = *(int *)data; dev_t device = tp->t_dev; @@ -1091,10 +1356,15 @@ ttioctl(struct tty *tp, error = ENXIO; goto out; } + /* + * If the new line discipline is not equal to the old one, + * close the old one and open the new one. + */ if (t != tp->t_line) { (*linesw[tp->t_line].l_close)(tp, flag); error = (*linesw[t].l_open)(device, tp); if (error) { + /* This is racy; it's possible to lose both */ (void)(*linesw[tp->t_line].l_open)(device, tp); goto out; } @@ -1102,7 +1372,7 @@ ttioctl(struct tty *tp, } break; } - case TIOCSTART: /* start output, like ^Q */ + case TIOCSTART: /* start output, like ^Q */ if (ISSET(tp->t_state, TS_TTSTOP) || ISSET(tp->t_lflag, FLUSHO)) { CLR(tp->t_lflag, FLUSHO); @@ -1110,7 +1380,7 @@ ttioctl(struct tty *tp, ttstart(tp); } break; - case TIOCSTI: /* simulate terminal input */ + case TIOCSTI: /* simulate terminal input */ if (suser(kauth_cred_get(), NULL) && (flag & FREAD) == 0) { error = EPERM; goto out; @@ -1121,10 +1391,10 @@ ttioctl(struct tty *tp, } (*linesw[tp->t_line].l_rint)(*(u_char *)data, tp); break; - case TIOCSTOP: /* stop output, like ^S */ + case TIOCSTOP: /* stop output, like ^S */ if (!ISSET(tp->t_state, TS_TTSTOP)) { SET(tp->t_state, TS_TTSTOP); - ttystop(tp, 0); + ttystop(tp, 0); } break; case TIOCIXON: @@ -1133,59 +1403,122 @@ ttioctl(struct tty *tp, case TIOCIXOFF: ttyblock(tp); break; - case TIOCSCTTY: /* become controlling tty */ + case TIOCSCTTY: /* become controlling tty */ /* Session ctty vnode pointer set in vnode layer. */ - pg = proc_pgrp(p); sessp = proc_session(p); - if (!SESS_LEADER(p, sessp) || - ((sessp->s_ttyvp || tp->t_session) && - (tp->t_session != sessp))) { - if (sessp != SESSION_NULL) - session_rele(sessp); - if (pg != PGRP_NULL) + if (sessp == SESSION_NULL) { + error = EPERM; + goto out; + } + + /* + * This can only be done by a session leader. + */ + if (!SESS_LEADER(p, sessp)) { + /* SAFE: All callers drop the lock on return */ + tty_unlock(tp); + session_rele(sessp); + tty_lock(tp); + error = EPERM; + goto out; + } + /* + * If this terminal is already the controlling terminal for the + * session, nothing to do here. + */ + if (tp->t_session == sessp) { + /* SAFE: All callers drop the lock on return */ + tty_unlock(tp); + session_rele(sessp); + tty_lock(tp); + error = 0; + goto out; + } + pg = proc_pgrp(p); + /* + * Deny if the terminal is already attached to another session or + * the session already has a terminal vnode. + */ + session_lock(sessp); + if (sessp->s_ttyvp || tp->t_session) { + session_unlock(sessp); + /* SAFE: All callers drop the lock on return */ + tty_unlock(tp); + if (pg != PGRP_NULL) { pg_rele(pg); + } + session_rele(sessp); + tty_lock(tp); error = EPERM; goto out; } + sessp->s_ttypgrpid = pg->pg_id; + oldtp = sessp->s_ttyp; + ttyhold(tp); + sessp->s_ttyp = tp; + session_unlock(sessp); proc_list_lock(); oldsessp = tp->t_session; oldpg = tp->t_pgrp; - if (oldsessp != SESSION_NULL) + if (oldsessp != SESSION_NULL) { oldsessp->s_ttypgrpid = NO_PID; + } /* do not drop refs on sessp and pg as tp holds them */ tp->t_session = sessp; - sessp->s_ttypgrpid = pg->pg_id; tp->t_pgrp = pg; proc_list_unlock(); - session_lock(sessp); - sessp->s_ttyp = tp; - session_unlock(sessp); - OSBitOrAtomic(P_CONTROLT, (UInt32 *)&p->p_flag); + OSBitOrAtomic(P_CONTROLT, &p->p_flag); + /* SAFE: All callers drop the lock on return */ + tty_unlock(tp); /* drop the reference on prev session and pgrp */ - if (oldsessp != SESSION_NULL) + if (oldsessp != SESSION_NULL) { session_rele(oldsessp); - if (oldpg != PGRP_NULL) + } + if (oldpg != PGRP_NULL) { pg_rele(oldpg); + } + if (NULL != oldtp) { + ttyfree(oldtp); + } + tty_lock(tp); break; - case TIOCSPGRP: { /* set pgrp of tty */ + case TIOCSPGRP: { /* set pgrp of tty */ struct pgrp *pgrp = PGRP_NULL; sessp = proc_session(p); if (!isctty_sp(p, tp, sessp)) { - if (sessp != SESSION_NULL) + if (sessp != SESSION_NULL) { session_rele(sessp); + } error = ENOTTY; goto out; - } - else if ((pgrp = pgfind(*(int *)data)) == PGRP_NULL) { - if (sessp != SESSION_NULL) + } else if ((pgrp = pgfind(*(int *)data)) == PGRP_NULL) { + if (sessp != SESSION_NULL) { session_rele(sessp); + } error = EINVAL; goto out; - } else if (pgrp->pg_session != sessp) { - if (sessp != SESSION_NULL) + } else if (pgrp->pg_session != sessp) { + /* SAFE: All callers drop the lock on return */ + tty_unlock(tp); + if (sessp != SESSION_NULL) { + session_rele(sessp); + } + pg_rele(pgrp); + tty_lock(tp); + error = EPERM; + goto out; + } + /* + * The session leader is going away and is possibly going to revoke + * the terminal, we can't change the process group when that is the + * case. + */ + if (ISSET(tp->t_state, TS_PGRPHUP)) { + if (sessp != SESSION_NULL) { session_rele(sessp); + } pg_rele(pgrp); error = EPERM; goto out; @@ -1195,20 +1528,45 @@ ttioctl(struct tty *tp, tp->t_pgrp = pgrp; sessp->s_ttypgrpid = pgrp->pg_id; proc_list_unlock(); - if (oldpg != PGRP_NULL) + + /* + * Wakeup readers to recheck if they are still the foreground + * process group. + * + * ttwakeup() isn't called because the readers aren't getting + * woken up becuse there is something to read but to force + * the re-evaluation of their foreground process group status. + * + * Ordinarily leaving these readers waiting wouldn't be an issue + * as launchd would send them a termination signal eventually + * (if nobody else does). But if this terminal happens to be + * /dev/console, launchd itself could get blocked forever behind + * a revoke of /dev/console and leave the system deadlocked. + */ + wakeup(TSA_HUP_OR_INPUT(tp)); + + /* SAFE: All callers drop the lock on return */ + tty_unlock(tp); + if (oldpg != PGRP_NULL) { pg_rele(oldpg); - if (sessp != SESSION_NULL) + } + if (sessp != SESSION_NULL) { session_rele(sessp); + } + tty_lock(tp); break; } - case TIOCSTAT: /* simulate control-T */ - ttyinfo(tp); + case TIOCSTAT: /* simulate control-T */ + ttyinfo_locked(tp); break; - case TIOCSWINSZ: /* set window size */ + case TIOCSWINSZ: /* set window size */ if (bcmp((caddr_t)&tp->t_winsize, data, - sizeof (struct winsize))) { + sizeof(struct winsize))) { tp->t_winsize = *(struct winsize *)data; + /* SAFE: All callers drop the lock on return */ + tty_unlock(tp); tty_pgsignal(tp, SIGWINCH, 1); + tty_lock(tp); } break; case TIOCSDRAINWAIT: @@ -1222,130 +1580,222 @@ ttioctl(struct tty *tp, break; case TIOCGDRAINWAIT: *(int *)data = tp->t_timeout / hz; - break; + break; + case TIOCREVOKE: + if (ISSET(tp->t_state, TS_PGRPHUP)) { + tp->t_gen++; + wakeup(TSA_HUP_OR_INPUT(tp)); + } + break; default: -#if COMPAT_43_TTY || defined(COMPAT_SUNOS) error = ttcompat(tp, cmd, data, flag, p); -#else - error = ENOTTY; -#endif goto out; } error = 0; out: - return(error); + return error; } + +/* + * Locks: Assumes tp is locked on entry, remains locked on exit + */ int ttyselect(struct tty *tp, int rw, void *wql, proc_t p) { - if (tp == NULL) - return (ENXIO); + int retval = 0; + /* + * Attaching knotes to TTYs needs to call selrecord in order to hook + * up the waitq to the selinfo, regardless of data being ready. See + * filt_ttyattach. + */ + bool needs_selrecord = rw & FMARK; + rw &= ~FMARK; + + if (tp == NULL) { + return ENXIO; + } + + TTY_LOCK_OWNED(tp); + + if (tp->t_state & TS_ZOMBIE) { + retval = 1; + goto out; + } switch (rw) { case FREAD: - if (ttnread(tp) > 0 || ISSET(tp->t_state, TS_ZOMBIE)) - return(1); + retval = ttnread(tp); + if (retval > 0) { + break; + } + selrecord(p, &tp->t_rsel, wql); break; case FWRITE: - if ((tp->t_outq.c_cc <= tp->t_lowat && - ISSET(tp->t_state, TS_CONNECTED)) - || ISSET(tp->t_state, TS_ZOMBIE)) { - return (1); + if ((tp->t_outq.c_cc <= tp->t_lowat) && + (tp->t_state & TS_CONNECTED)) { + retval = tp->t_hiwat - tp->t_outq.c_cc; + break; } + selrecord(p, &tp->t_wsel, wql); break; } - return (0); + +out: + if (retval > 0 && needs_selrecord) { + switch (rw) { + case FREAD: + selrecord(p, &tp->t_rsel, wql); + break; + case FWRITE: + selrecord(p, &tp->t_wsel, wql); + break; + } + } + + return retval; } + /* * This is a wrapper for compatibility with the select vector used by * cdevsw. It relies on a proper xxxdevtotty routine. + * + * Locks: Assumes tty_lock() is not held prior to calling. */ int ttselect(dev_t dev, int rw, void *wql, proc_t p) { - return ttyselect(cdevsw[major(dev)].d_ttys[minor(dev)], rw, wql, p); + int rv; + struct tty *tp = cdevsw[major(dev)].d_ttys[minor(dev)]; + + tty_lock(tp); + rv = ttyselect(tp, rw, wql, p); + tty_unlock(tp); + + return rv; } + /* - * Must be called at spltty(). + * Locks: Assumes tp is locked on entry, remains locked on exit */ -static int +__private_extern__ int ttnread(struct tty *tp) { int nread; - if (ISSET(tp->t_lflag, PENDIN)) + TTY_LOCK_OWNED(tp); /* debug assert */ + + if (ISSET(tp->t_lflag, PENDIN)) { ttypend(tp); + } nread = tp->t_canq.c_cc; if (!ISSET(tp->t_lflag, ICANON)) { nread += tp->t_rawq.c_cc; - if (nread < tp->t_cc[VMIN] && tp->t_cc[VTIME] == 0) + if (nread < tp->t_cc[VMIN] && tp->t_cc[VTIME] == 0) { nread = 0; + } } - return (nread); + return nread; } + /* + * ttywait + * * Wait for output to drain. + * + * Parameters: tp Tty on which to wait for output to drain + * + * Returns: 0 Success + * EIO t_timeout too small/expired + * ttysleep:ERESTART Upper layer must redrive the call; + * this is usually done by the Libc + * stub in user space + * ttysleep:EINTR Interrupted (usually a signal) + * + * Notes: Called from proc_exit() and vproc_exit(). + * + * Locks: Assumes tp is locked on entry, remains locked on exit */ int ttywait(struct tty *tp) { int error; + TTY_LOCK_OWNED(tp); /* debug assert */ + error = 0; while ((tp->t_outq.c_cc || ISSET(tp->t_state, TS_BUSY)) && - ISSET(tp->t_state, TS_CONNECTED) && tp->t_oproc) { + ISSET(tp->t_state, TS_CONNECTED) && tp->t_oproc) { (*tp->t_oproc)(tp); if ((tp->t_outq.c_cc || ISSET(tp->t_state, TS_BUSY)) && ISSET(tp->t_state, TS_CONNECTED)) { SET(tp->t_state, TS_SO_OCOMPLETE); error = ttysleep(tp, TSA_OCOMPLETE(tp), - TTOPRI | PCATCH, "ttywai", - tp->t_timeout); + TTOPRI | PCATCH, "ttywai", + tp->t_timeout); if (error) { - if (error == EWOULDBLOCK) + if (error == EWOULDBLOCK) { error = EIO; + } break; } - } else + } else { break; + } } - if (!error && (tp->t_outq.c_cc || ISSET(tp->t_state, TS_BUSY))) + if (!error && (tp->t_outq.c_cc || ISSET(tp->t_state, TS_BUSY))) { error = EIO; - return (error); + } + return error; } +/* + * Stop the underlying device driver. + * + * Locks: Assumes tty_lock() is held prior to calling. + */ static void ttystop(struct tty *tp, int rw) { + TTY_LOCK_OWNED(tp); /* debug assert */ + (*cdevsw[major(tp->t_dev)].d_stop)(tp, rw); } /* * Flush if successfully wait. + * + * Locks: Assumes tty_lock() is held prior to calling. */ static int ttywflush(struct tty *tp) { int error; - if ((error = ttywait(tp)) == 0) + TTY_LOCK_OWNED(tp); /* debug assert */ + + if ((error = ttywait(tp)) == 0) { ttyflush(tp, FREAD); - return (error); + } + return error; } /* * Flush tty read and/or write queues, notifying anyone waiting. + * + * Locks: Assumes tty_lock() is held prior to calling. */ void ttyflush(struct tty *tp, int rw) { + TTY_LOCK_OWNED(tp); /* debug assert */ + #if 0 again: #endif @@ -1353,8 +1803,8 @@ again: FLUSHQ(&tp->t_outq); CLR(tp->t_state, TS_TTSTOP); } - ttystop(tp, rw); - if (rw & FREAD) { + ttystop(tp, rw); + if (rw & FREAD) { FLUSHQ(&tp->t_canq); FLUSHQ(&tp->t_rawq); CLR(tp->t_lflag, PENDIN); @@ -1363,8 +1813,9 @@ again: CLR(tp->t_state, TS_LOCAL); ttwakeup(tp); if (ISSET(tp->t_state, TS_TBLOCK)) { - if (rw & FWRITE) + if (rw & FWRITE) { FLUSHQ(&tp->t_outq); + } ttyunblock(tp); /* @@ -1389,7 +1840,7 @@ again: */ SET(tp->t_state, TS_SO_OCOMPLETE); ttysleep(tp, TSA_OCOMPLETE(tp), TTOPRI, - "ttyfls", hz / 10); + "ttyfls", hz / 10); /* * Don't try sending the stop character again. */ @@ -1407,6 +1858,10 @@ again: /* * Copy in the default termios characters. + * + * Locks: Assumes tty_lock() is held prior to calling. + * + * Notes: No assertion; tp is not in scope. */ void termioschars(struct termios *t) @@ -1414,104 +1869,113 @@ termioschars(struct termios *t) bcopy(ttydefchars, t->c_cc, sizeof t->c_cc); } -/* - * Old interface. - */ -void -ttychars(struct tty *tp) -{ - termioschars(&tp->t_termios); -} /* * Handle input high water. Send stop character for the IXOFF case. Turn * on our input flow control bit and propagate the changes to the driver. * XXX the stop character should be put in a special high priority queue. + * + * Locks: Assumes tty_lock() is held for the call. */ void ttyblock(struct tty *tp) { + TTY_LOCK_OWNED(tp); /* debug assert */ + SET(tp->t_state, TS_TBLOCK); if (ISSET(tp->t_iflag, IXOFF) && tp->t_cc[VSTOP] != _POSIX_VDISABLE && - putc(tp->t_cc[VSTOP], &tp->t_outq) != 0) - CLR(tp->t_state, TS_TBLOCK); /* try again later */ + putc(tp->t_cc[VSTOP], &tp->t_outq) != 0) { + CLR(tp->t_state, TS_TBLOCK); /* try again later */ + } ttstart(tp); } + /* * Handle input low water. Send start character for the IXOFF case. Turn * off our input flow control bit and propagate the changes to the driver. * XXX the start character should be put in a special high priority queue. + * + * Locks: Assumes tty_lock() is held for the call. */ static void ttyunblock(struct tty *tp) { + TTY_LOCK_OWNED(tp); /* debug assert */ + CLR(tp->t_state, TS_TBLOCK); if (ISSET(tp->t_iflag, IXOFF) && tp->t_cc[VSTART] != _POSIX_VDISABLE && - putc(tp->t_cc[VSTART], &tp->t_outq) != 0) - SET(tp->t_state, TS_TBLOCK); /* try again later */ + putc(tp->t_cc[VSTART], &tp->t_outq) != 0) { + SET(tp->t_state, TS_TBLOCK); /* try again later */ + } ttstart(tp); } -/* FreeBSD: Not used by any current (i386) drivers. */ + /* - * Restart after an inter-char delay. + * ttstart + * + * Start tty output + * + * Parameters: tp tty on which to start output + * + * Returns: 0 Success + * + * Locks: Assumes tty_lock() is held for the call. + * + * Notes: This function might as well be void; it always returns success + * + * Called from ttioctl_locked(), LDISC routines, and + * ttycheckoutq(), ttyblock(), ttyunblock(), and tputchar() */ -void -ttrstrt(void *tp_arg) -{ - struct tty *tp; - -#if DIAGNOSTIC - if (tp_arg == NULL) - panic("ttrstrt"); -#endif - tp = tp_arg; - - CLR(tp->t_state, TS_TIMEOUT); - ttstart(tp); - -} - int ttstart(struct tty *tp) { - boolean_t funnel_state; - - funnel_state = thread_funnel_set(kernel_flock, TRUE); + TTY_LOCK_OWNED(tp); /* debug assert */ - if (tp->t_oproc != NULL) /* XXX: Kludge for pty. */ + if (tp->t_oproc != NULL) { /* XXX: Kludge for pty. */ (*tp->t_oproc)(tp); - thread_funnel_set(kernel_flock, funnel_state); - return (0); + } + + return 0; } + /* + * ttylclose (LDISC) + * * "close" a line discipline + * + * Locks: Assumes tty_lock() is held prior to calling. */ int ttylclose(struct tty *tp, int flag) { - boolean_t funnel_state; + TTY_LOCK_OWNED(tp); /* debug assert */ - funnel_state = thread_funnel_set(kernel_flock, TRUE); - if ( (flag & FNONBLOCK) || ttywflush(tp)) + if ((flag & FNONBLOCK) || ttywflush(tp)) { ttyflush(tp, FREAD | FWRITE); - thread_funnel_set(kernel_flock, funnel_state); - return (0); + } + + return 0; } + /* + * ttymodem (LDISC) + * * Handle modem control transition on a tty. * Flag indicates new state of carrier. * Returns 0 if the line should be turned off, otherwise 1. + * + * Locks: Assumes tty_lock() is held prior to calling. */ int ttymodem(struct tty *tp, int flag) { - boolean_t funnel_state; + int rval = 1; /* default return value */ - funnel_state = thread_funnel_set(kernel_flock, TRUE); + TTY_LOCK_OWNED(tp); /* debug assert */ if (ISSET(tp->t_state, TS_CARR_ON) && ISSET(tp->t_cflag, MDMBUF)) { /* @@ -1526,7 +1990,7 @@ ttymodem(struct tty *tp, int flag) } else if (!ISSET(tp->t_state, TS_CAR_OFLOW)) { SET(tp->t_state, TS_CAR_OFLOW); SET(tp->t_state, TS_TTSTOP); - ttystop(tp, 0); + ttystop(tp, 0); } } else if (flag == 0) { /* @@ -1537,30 +2001,36 @@ ttymodem(struct tty *tp, int flag) !ISSET(tp->t_cflag, CLOCAL)) { SET(tp->t_state, TS_ZOMBIE); CLR(tp->t_state, TS_CONNECTED); - if (tp->t_session && tp->t_session->s_leader) + if (tp->t_session && tp->t_session->s_leader) { psignal(tp->t_session->s_leader, SIGHUP); + } ttyflush(tp, FREAD | FWRITE); - thread_funnel_set(kernel_flock, funnel_state); - return (0); + rval = 0; + goto out; } } else { /* * Carrier now on. */ SET(tp->t_state, TS_CARR_ON); - if (!ISSET(tp->t_state, TS_ZOMBIE)) + if (!ISSET(tp->t_state, TS_ZOMBIE)) { SET(tp->t_state, TS_CONNECTED); + } wakeup(TSA_CARR_ON(tp)); ttwakeup(tp); ttwwakeup(tp); } - thread_funnel_set(kernel_flock, funnel_state); - return (1); + +out: + return rval; } + /* * Reinput pending characters after state switch * call at spltty(). + * + * Locks: Assumes tty_lock() is held for the call. */ static void ttypend(struct tty *tp) @@ -1568,18 +2038,26 @@ ttypend(struct tty *tp) struct clist tq; int c; + TTY_LOCK_OWNED(tp); /* debug assert */ + CLR(tp->t_lflag, PENDIN); SET(tp->t_state, TS_TYPEN); tq = tp->t_rawq; tp->t_rawq.c_cc = 0; tp->t_rawq.c_cf = tp->t_rawq.c_cl = NULL; - while ((c = getc(&tq)) >= 0) + while ((c = getc(&tq)) >= 0) { ttyinput(c, tp); + } CLR(tp->t_state, TS_TYPEN); } + /* + * ttread (LDISC) + * * Process a read call on a tty device. + * + * Locks: Assumes tty_lock() is held prior to calling. */ int ttread(struct tty *tp, struct uio *uio, int flag) @@ -1591,12 +2069,11 @@ ttread(struct tty *tp, struct uio *uio, int flag) proc_t p = current_proc(); int first, error = 0; int has_etime = 0, last_cc = 0; - long slp = 0; /* XXX this should be renamed `timo'. */ - boolean_t funnel_state; + long slp = 0; /* XXX this should be renamed `timo'. */ struct uthread *ut; struct pgrp * pg; - funnel_state = thread_funnel_set(kernel_flock, TRUE); + TTY_LOCK_OWNED(tp); /* debug assert */ ut = (struct uthread *)get_bsdthread_info(current_thread()); @@ -1607,7 +2084,7 @@ loop: */ if (ISSET(lflag, PENDIN)) { ttypend(tp); - lflag = tp->t_lflag; /* XXX ttypend() clobbers it */ + lflag = tp->t_lflag; /* XXX ttypend() clobbers it */ } /* @@ -1615,23 +2092,29 @@ loop: */ if (isbackground(p, tp)) { if ((p->p_sigignore & sigmask(SIGTTIN)) || - (ut->uu_sigmask & sigmask(SIGTTIN)) || + (ut->uu_sigmask & sigmask(SIGTTIN)) || p->p_lflag & P_LPPWAIT) { - thread_funnel_set(kernel_flock, funnel_state); - return (EIO); + error = EIO; + goto err; } pg = proc_pgrp(p); if (pg == PGRP_NULL) { - thread_funnel_set(kernel_flock, funnel_state); - return (EIO); + error = EIO; + goto err; } if (pg->pg_jobc == 0) { + /* SAFE: All callers drop the lock on return */ + tty_unlock(tp); pg_rele(pg); - thread_funnel_set(kernel_flock, funnel_state); - return (EIO); + tty_lock(tp); + error = EIO; + goto err; } + /* SAFE: All callers drop the lock on return */ + tty_unlock(tp); pgsignal(pg, SIGTTIN, 1); pg_rele(pg); + tty_lock(tp); /* * We signalled ourself, so we need to act as if we @@ -1639,13 +2122,13 @@ loop: * the signal. If it's a signal that stops the * process, that's handled in the signal sending code. */ - thread_funnel_set(kernel_flock, funnel_state); - return (EINTR); + error = EINTR; + goto err; } if (ISSET(tp->t_state, TS_ZOMBIE)) { - thread_funnel_set(kernel_flock, funnel_state); - return (0); /* EOF */ + /* EOF - returning 0 */ + goto err; } /* @@ -1657,20 +2140,20 @@ loop: qp = ISSET(lflag, ICANON) ? &tp->t_canq : &tp->t_rawq; if (flag & IO_NDELAY) { - if (qp->c_cc > 0) + if (qp->c_cc > 0) { goto read; - if (!ISSET(lflag, ICANON) && cc[VMIN] == 0) { - thread_funnel_set(kernel_flock, funnel_state); - return (0); } - thread_funnel_set(kernel_flock, funnel_state); - return (EWOULDBLOCK); + if (ISSET(lflag, ICANON) || cc[VMIN] != 0) { + error = EWOULDBLOCK; + } + /* else polling - returning 0 */ + goto err; } if (!ISSET(lflag, ICANON)) { int m = cc[VMIN]; long t = cc[VTIME]; struct timeval timecopy; - struct timeval etime = {0, 0}; /* protected by !has_etime */ + struct timeval etime = {.tv_sec = 0, .tv_usec = 0}; /* protected by !has_etime */ /* * Check each of the four combinations. @@ -1681,23 +2164,26 @@ loop: * into slp. */ if (t == 0) { - if (qp->c_cc < m) + if (qp->c_cc < m) { goto sleep; - if (qp->c_cc > 0) + } + if (qp->c_cc > 0) { goto read; + } /* m, t and qp->c_cc are all 0. 0 is enough input. */ - thread_funnel_set(kernel_flock, funnel_state); - return (0); + goto err; } - t *= 100000; /* time in us */ + t *= 100000; /* time in us */ #define diff(t1, t2) (((t1).tv_sec - (t2).tv_sec) * 1000000 + \ - ((t1).tv_usec - (t2).tv_usec)) + ((t1).tv_usec - (t2).tv_usec)) if (m > 0) { - if (qp->c_cc <= 0) + if (qp->c_cc <= 0) { goto sleep; - if (qp->c_cc >= m) + } + if (qp->c_cc >= m) { goto read; + } microuptime(&timecopy); if (!has_etime) { /* first character, start timer */ @@ -1706,7 +2192,7 @@ loop: etime.tv_sec = t / 1000000; etime.tv_usec = (t - (etime.tv_sec * 1000000)); timeradd(&etime, &timecopy, &etime); - + slp = t; } else if (qp->c_cc > last_cc) { /* got a character, restart timer */ @@ -1718,15 +2204,17 @@ loop: slp = t; } else { /* nothing, check expiration */ - if (timercmp(&etime, &timecopy, <=)) + if (timercmp(&etime, &timecopy, <=)) { goto read; + } slp = diff(etime, timecopy); } last_cc = qp->c_cc; - } else { /* m == 0 */ - if (qp->c_cc > 0) + } else { /* m == 0 */ + if (qp->c_cc > 0) { goto read; + } microuptime(&timecopy); if (!has_etime) { has_etime = 1; @@ -1737,10 +2225,9 @@ loop: slp = t; } else { - if (timercmp(&etime, &timecopy, <=)) { + if (timercmp(&etime, &timecopy, <=)) { /* Timed out, but 0 is enough input. */ - thread_funnel_set(kernel_flock, funnel_state); - return (0); + goto err; } slp = diff(etime, timecopy); } @@ -1755,7 +2242,7 @@ loop: * is large (divide by `tick' and/or arrange to * use hzto() if hz is large). */ - slp = (long) (((u_long)slp * hz) + 999999) / 1000000; + slp = (long) (((u_int32_t)slp * hz) + 999999) / 1000000; goto sleep; } if (qp->c_cc <= 0) { @@ -1764,13 +2251,12 @@ sleep: * There is no input, or not enough input and we can block. */ error = ttysleep(tp, TSA_HUP_OR_INPUT(tp), TTIPRI | PCATCH, - ISSET(tp->t_state, TS_CONNECTED) ? - "ttyin" : "ttyhup", (int)slp); - if (error == EWOULDBLOCK) + ISSET(tp->t_state, TS_CONNECTED) ? + "ttyin" : "ttyhup", (int)slp); + if (error == EWOULDBLOCK) { error = 0; - else if (error) { - thread_funnel_set(kernel_flock, funnel_state); - return (error); + } else if (error) { + goto err; } /* * XXX what happens if another process eats some input @@ -1787,17 +2273,19 @@ read: */ first = 1; if (ISSET(lflag, ICANON) - || (ISSET(lflag, IEXTEN | ISIG) == (IEXTEN | ISIG)) ) + || (ISSET(lflag, IEXTEN | ISIG) == (IEXTEN | ISIG))) { goto slowcase; + } for (;;) { char ibuf[IBUFSIZ]; int icc; - icc = min(uio_resid(uio), IBUFSIZ); + icc = MIN(uio_resid(uio), IBUFSIZ); icc = q_to_b(qp, (u_char *)ibuf, icc); if (icc <= 0) { - if (first) + if (first) { goto loop; + } break; } error = uiomove(ibuf, icc, uio); @@ -1805,10 +2293,12 @@ read: * XXX if there was an error then we should ungetc() the * unmoved chars and reduce icc here. */ - if (error) + if (error) { break; - if (uio_resid(uio) == 0) + } + if (uio_resid(uio) == 0) { break; + } first = 0; } goto out; @@ -1816,8 +2306,9 @@ slowcase: for (;;) { c = getc(qp); if (c < 0) { - if (first) + if (first) { goto loop; + } break; } /* @@ -1825,12 +2316,20 @@ slowcase: */ if (CCEQ(cc[VDSUSP], c) && ISSET(lflag, IEXTEN | ISIG) == (IEXTEN | ISIG)) { + /* + * SAFE: All callers drop the lock on return and + * SAFE: current thread will not change out from + * SAFE: under us in the "goto loop" case. + */ + tty_unlock(tp); tty_pgsignal(tp, SIGTSTP, 1); + tty_lock(tp); if (first) { - error = ttysleep(tp, &lbolt, TTIPRI | PCATCH, - "ttybg3", 0); - if (error) + error = ttysleep(tp, &ttread, TTIPRI | PCATCH, + "ttybg3", hz); + if (error) { break; + } goto loop; } break; @@ -1838,23 +2337,27 @@ slowcase: /* * Interpret EOF only in canonical mode. */ - if (CCEQ(cc[VEOF], c) && ISSET(lflag, ICANON)) + if (CCEQ(cc[VEOF], c) && ISSET(lflag, ICANON)) { break; + } /* * Give user character. */ - error = ureadc(c, uio); - if (error) + error = ureadc(c, uio); + if (error) { /* XXX should ungetc(c, qp). */ break; - if (uio_resid(uio) == 0) + } + if (uio_resid(uio) == 0) { break; + } /* * In canonical mode check for a "break character" * marking the end of a "line of input". */ - if (ISSET(lflag, ICANON) && TTBREAKC(c, lflag)) + if (ISSET(lflag, ICANON) && TTBREAKC(c, lflag)) { break; + } first = 0; } @@ -1864,19 +2367,25 @@ out: * the input queue has gone down. */ if (ISSET(tp->t_state, TS_TBLOCK) && - tp->t_rawq.c_cc + tp->t_canq.c_cc <= I_LOW_WATER) + tp->t_rawq.c_cc + tp->t_canq.c_cc <= I_LOW_WATER) { ttyunblock(tp); + } - thread_funnel_set(kernel_flock, funnel_state); - return (error); +err: + return error; } + /* * Check the output queue on tp for space for a kernel message (from uprintf * or tprintf). Allow some space over the normal hiwater mark so we don't * lose messages due to normal flow control, but don't let the tty run amok. * Sleeps here are not interruptible, but we return prematurely if new signals * arrive. + * + * Locks: Assumes tty_lock() is held before calling + * + * Notes: This function is called from tprintf() in subr_prf.c */ int ttycheckoutq(struct tty *tp, int wait) @@ -1885,26 +2394,35 @@ ttycheckoutq(struct tty *tp, int wait) sigset_t oldsig; struct uthread *ut; + TTY_LOCK_OWNED(tp); /* debug assert */ + ut = (struct uthread *)get_bsdthread_info(current_thread()); hiwat = tp->t_hiwat; oldsig = wait ? ut->uu_siglist : 0; - if (tp->t_outq.c_cc > hiwat + OBUFSIZ + 100) + if (tp->t_outq.c_cc > hiwat + OBUFSIZ + 100) { while (tp->t_outq.c_cc > hiwat) { ttstart(tp); - if (tp->t_outq.c_cc <= hiwat) + if (tp->t_outq.c_cc <= hiwat) { break; + } if (wait == 0 || ut->uu_siglist != oldsig) { - return (0); + return 0; } SET(tp->t_state, TS_SO_OLOWAT); - tsleep(TSA_OLOWAT(tp), PZERO - 1, "ttoutq", hz); + ttysleep(tp, TSA_OLOWAT(tp), PZERO - 1, "ttoutq", hz); } - return (1); + } + return 1; } + /* + * ttwrite (LDISC) + * * Process a write call on a tty device. + * + * Locks: Assumes tty_lock() is held prior to calling. */ int ttwrite(struct tty *tp, struct uio *uio, int flag) @@ -1912,24 +2430,24 @@ ttwrite(struct tty *tp, struct uio *uio, int flag) char *cp = NULL; int cc, ce; proc_t p; - int i, hiwat, count, error; + int i, hiwat, error; + user_ssize_t count; char obuf[OBUFSIZ]; - boolean_t funnel_state; struct uthread *ut; struct pgrp * pg; - funnel_state = thread_funnel_set(kernel_flock, TRUE); + TTY_LOCK_OWNED(tp); /* debug assert */ ut = (struct uthread *)get_bsdthread_info(current_thread()); hiwat = tp->t_hiwat; - // LP64todo - fix this! count = uio_resid(uio); error = 0; cc = 0; loop: if (ISSET(tp->t_state, TS_ZOMBIE)) { - if (uio_resid(uio) == count) + if (uio_resid(uio) == count) { error = EIO; + } goto out; } if (!ISSET(tp->t_state, TS_CONNECTED)) { @@ -1938,9 +2456,10 @@ loop: goto out; } error = ttysleep(tp, TSA_CARR_ON(tp), TTIPRI | PCATCH, - "ttydcd", 0); + "ttydcd", 0); if (error) { - goto out; } + goto out; + } goto loop; } /* @@ -1951,19 +2470,24 @@ loop: ISSET(tp->t_lflag, TOSTOP) && (p->p_lflag & P_LPPWAIT) == 0 && (p->p_sigignore & sigmask(SIGTTOU)) == 0 && (ut->uu_sigmask & sigmask(SIGTTOU)) == 0) { - pg = proc_pgrp(p); if (pg == PGRP_NULL) { error = EIO; goto out; } if (pg->pg_jobc == 0) { + /* SAFE: All callers drop the lock on return */ + tty_unlock(tp); pg_rele(pg); + tty_lock(tp); error = EIO; goto out; } + /* SAFE: All callers drop the lock on return */ + tty_unlock(tp); pgsignal(pg, SIGTTOU, 1); pg_rele(pg); + tty_lock(tp); /* * We signalled ourself, so we need to act as if we * have been "interrupted" from a "sleep" to act on @@ -1971,7 +2495,7 @@ loop: * process, that's handled in the signal sending code. */ error = EINTR; - goto out; + goto out; } /* * Process the user's data in at most OBUFSIZ chunks. Perform any @@ -1981,17 +2505,17 @@ loop: while (uio_resid(uio) > 0 || cc > 0) { if (ISSET(tp->t_lflag, FLUSHO)) { uio_setresid(uio, 0); - thread_funnel_set(kernel_flock, funnel_state); - return (0); + return 0; } - if (tp->t_outq.c_cc > hiwat) + if (tp->t_outq.c_cc > hiwat) { goto ovhiwat; + } /* * Grab a hunk of data from the user, unless we have some * leftover from last time. */ if (cc == 0) { - cc = min(uio_resid(uio), OBUFSIZ); + cc = MIN(uio_resid(uio), OBUFSIZ); cp = obuf; error = uiomove(cp, cc, uio); if (error) { @@ -2009,11 +2533,11 @@ loop: * immediately. */ while (cc > 0) { - if (!ISSET(tp->t_oflag, OPOST)) + if (!ISSET(tp->t_oflag, OPOST)) { ce = cc; - else { + } else { ce = cc - scanc((u_int)cc, (u_char *)cp, - char_type, CCLASSMASK); + char_type, CCLASSMASK); /* * If ce is zero, then we're processing * a special character through ttyoutput. @@ -2027,8 +2551,9 @@ loop: cp++; cc--; if (ISSET(tp->t_lflag, FLUSHO) || - tp->t_outq.c_cc > hiwat) + tp->t_outq.c_cc > hiwat) { goto ovhiwat; + } continue; } } @@ -2044,15 +2569,18 @@ loop: i = b_to_q((u_char *)cp, ce, &tp->t_outq); ce -= i; tp->t_column += ce; - cp += ce, cc -= ce, tk_nout += ce; + cp += ce; + cc -= ce; + tk_nout += ce; tp->t_outcc += ce; if (i > 0) { /* out of space */ goto overfull; } if (ISSET(tp->t_lflag, FLUSHO) || - tp->t_outq.c_cc > hiwat) + tp->t_outq.c_cc > hiwat) { break; + } } ttstart(tp); } @@ -2063,8 +2591,7 @@ out: * (the call will either return short or restart with a new uio). */ uio_setresid(uio, (uio_resid(uio) + cc)); - thread_funnel_set(kernel_flock, funnel_state); - return (error); + return error; overfull: @@ -2087,22 +2614,26 @@ ovhiwat: } if (flag & IO_NDELAY) { uio_setresid(uio, (uio_resid(uio) + cc)); - thread_funnel_set(kernel_flock, funnel_state); - return (uio_resid(uio) == count ? EWOULDBLOCK : 0); + return uio_resid(uio) == count ? EWOULDBLOCK : 0; } SET(tp->t_state, TS_SO_OLOWAT); error = ttysleep(tp, TSA_OLOWAT(tp), TTOPRI | PCATCH, "ttywri", - tp->t_timeout); - if (error == EWOULDBLOCK) + tp->t_timeout); + if (error == EWOULDBLOCK) { error = EIO; - if (error) + } + if (error) { goto out; + } goto loop; } + /* * Rubout one character from the rawq of tp * as cleanly as possible. + * + * Locks: Assumes tty_lock() is held prior to calling. */ static void ttyrub(int c, struct tty *tp) @@ -2111,8 +2642,11 @@ ttyrub(int c, struct tty *tp) int savecol; int tabc; - if (!ISSET(tp->t_lflag, ECHO) || ISSET(tp->t_lflag, EXTPROC)) + TTY_LOCK_OWNED(tp); /* debug assert */ + + if (!ISSET(tp->t_lflag, ECHO) || ISSET(tp->t_lflag, EXTPROC)) { return; + } CLR(tp->t_lflag, FLUSHO); if (ISSET(tp->t_lflag, ECHOE)) { if (tp->t_rocount == 0) { @@ -2122,13 +2656,13 @@ ttyrub(int c, struct tty *tp) ttyretype(tp); return; } - if (c == ('\t' | TTY_QUOTE) || c == ('\n' | TTY_QUOTE)) + if (c == ('\t' | TTY_QUOTE) || c == ('\n' | TTY_QUOTE)) { ttyrubo(tp, 2); - else { + } else { CLR(c, ~TTY_CHARMASK); switch (CCLASS(c)) { case ORDINARY: - if(!(ISSET(tp->t_iflag, IUTF8) && CCONT(c))) { + if (!(ISSET(tp->t_iflag, IUTF8) && CCONT(c))) { ttyrubo(tp, 1); } break; @@ -2137,8 +2671,9 @@ ttyrub(int c, struct tty *tp) case NEWLINE: case RETURN: case VTAB: - if (ISSET(tp->t_lflag, ECHOCTL)) + if (ISSET(tp->t_lflag, ECHOCTL)) { ttyrubo(tp, 2); + } break; case TAB: if (tp->t_rocount < tp->t_rawq.c_cc) { @@ -2150,21 +2685,24 @@ ttyrub(int c, struct tty *tp) SET(tp->t_lflag, FLUSHO); tp->t_column = tp->t_rocol; for (cp = firstc(&tp->t_rawq, &tabc); cp; - cp = nextc(&tp->t_rawq, cp, &tabc)) + cp = nextc(&tp->t_rawq, cp, &tabc)) { ttyecho(tabc, tp); + } CLR(tp->t_lflag, FLUSHO); CLR(tp->t_state, TS_CNTTB); /* savecol will now be length of the tab. */ savecol -= tp->t_column; tp->t_column += savecol; - if (savecol > 8) - savecol = 8; /* overflow fixup */ - while (--savecol >= 0) + if (savecol > 8) { + savecol = 8; /* overflow fixup */ + } + while (--savecol >= 0) { (void)ttyoutput('\b', tp); + } break; - default: /* XXX */ -#define PANICSTR "ttyrub: would panic c = %d, val = %d\n" + default: /* XXX */ +#define PANICSTR "ttyrub: would panic c = %d, val = %d\n" printf(PANICSTR, c, CCLASS(c)); #ifdef notdef panic(PANICSTR, c, CCLASS(c)); @@ -2177,17 +2715,23 @@ ttyrub(int c, struct tty *tp) (void)ttyoutput('\\', tp); } ttyecho(c, tp); - } else + } else { ttyecho(tp->t_cc[VERASE], tp); + } --tp->t_rocount; } + /* * Back over count characters, erasing them. + * + * Locks: Assumes tty_lock() is held prior to calling. */ static void ttyrubo(struct tty *tp, int count) { + TTY_LOCK_OWNED(tp); /* debug assert */ + while (count-- > 0) { (void)ttyoutput('\b', tp); (void)ttyoutput(' ', tp); @@ -2195,10 +2739,13 @@ ttyrubo(struct tty *tp, int count) } } + /* * ttyretype -- * Reprint the rawq line. Note, it is assumed that c_cc has already * been checked. + * + * Locks: Assumes tty_lock() is held prior to calling. */ static void ttyretype(struct tty *tp) @@ -2206,9 +2753,12 @@ ttyretype(struct tty *tp) u_char *cp; int c; + TTY_LOCK_OWNED(tp); /* debug assert */ + /* Echo the reprint character. */ - if (tp->t_cc[VREPRINT] != _POSIX_VDISABLE) + if (tp->t_cc[VREPRINT] != _POSIX_VDISABLE) { ttyecho(tp->t_cc[VREPRINT], tp); + } (void)ttyoutput('\n', tp); @@ -2217,61 +2767,107 @@ ttyretype(struct tty *tp) * FIX: NEXTC IS BROKEN - DOESN'T CHECK QUOTE * BIT OF FIRST CHAR. */ - for (cp = firstc(&tp->t_canq, &c); cp; cp = nextc(&tp->t_canq, cp, &c)) + for (cp = firstc(&tp->t_canq, &c); cp; cp = nextc(&tp->t_canq, cp, &c)) { ttyecho(c, tp); - for (cp = firstc(&tp->t_rawq, &c); cp; cp = nextc(&tp->t_rawq, cp, &c)) + } + for (cp = firstc(&tp->t_rawq, &c); cp; cp = nextc(&tp->t_rawq, cp, &c)) { ttyecho(c, tp); + } CLR(tp->t_state, TS_ERASE); tp->t_rocount = tp->t_rawq.c_cc; tp->t_rocol = 0; } + /* * Echo a typed character to the terminal. + * + * Locks: Assumes tty_lock() is held prior to calling. */ static void ttyecho(int c, struct tty *tp) { - if (!ISSET(tp->t_state, TS_CNTTB)) + TTY_LOCK_OWNED(tp); /* debug assert */ + + if (!ISSET(tp->t_state, TS_CNTTB)) { CLR(tp->t_lflag, FLUSHO); + } if ((!ISSET(tp->t_lflag, ECHO) && - (c != '\n' || !ISSET(tp->t_lflag, ECHONL))) || - ISSET(tp->t_lflag, EXTPROC)) + (c != '\n' || !ISSET(tp->t_lflag, ECHONL))) || + ISSET(tp->t_lflag, EXTPROC)) { return; + } if (ISSET(tp->t_lflag, ECHOCTL) && ((ISSET(c, TTY_CHARMASK) <= 037 && c != '\t' && c != '\n') || ISSET(c, TTY_CHARMASK) == 0177)) { (void)ttyoutput('^', tp); CLR(c, ~TTY_CHARMASK); - if (c == 0177) + if (c == 0177) { c = '?'; - else + } else { c += 'A' - 1; + } } (void)ttyoutput(c, tp); } +static void +ttwakeup_knote(struct selinfo *sip, long hint) +{ + if ((sip->si_flags & SI_KNPOSTING) == 0) { + sip->si_flags |= SI_KNPOSTING; + KNOTE(&sip->si_note, hint); + sip->si_flags &= ~SI_KNPOSTING; + } +} + + /* * Wake up any readers on a tty. + * + * Locks: Assumes tty_lock() is held for the call. */ void ttwakeup(struct tty *tp) { + TTY_LOCK_OWNED(tp); /* debug assert */ + selwakeup(&tp->t_rsel); - if (ISSET(tp->t_state, TS_ASYNC)) + ttwakeup_knote(&tp->t_rsel, 0); + if (ISSET(tp->t_state, TS_ASYNC)) { + /* + * XXX: Callers may not revalidate it the tty is closed + * XXX: out from under them by another thread, but we do + * XXX: not support queued signals. This should be safe, + * XXX: since the process we intend to wakeup is in the + * XXX: process group, and will wake up because of the + * XXX: signal anyway. + */ + tty_unlock(tp); tty_pgsignal(tp, SIGIO, 1); + tty_lock(tp); + } wakeup(TSA_HUP_OR_INPUT(tp)); } + /* + * ttwwakeup (LDISC) + * * Wake up any writers on a tty. + * + * Locks: Assumes tty_lock() is held prior to calling. */ void ttwwakeup(struct tty *tp) { - if (tp->t_outq.c_cc <= tp->t_lowat) + TTY_LOCK_OWNED(tp); /* debug assert */ + + if (tp->t_outq.c_cc <= tp->t_lowat) { selwakeup(&tp->t_wsel); + ttwakeup_knote(&tp->t_wsel, 0); + } if (ISSET(tp->t_state, TS_BUSY | TS_SO_OCOMPLETE) == TS_SO_OCOMPLETE && tp->t_outq.c_cc == 0) { CLR(tp->t_state, TS_SO_OCOMPLETE); @@ -2284,25 +2880,33 @@ ttwwakeup(struct tty *tp) } } + /* * Look up a code for a specified speed in a conversion table; * used by drivers to map software speed values to hardware parameters. + * + * Notes: No locks are assumed for this function; it does not + * directly access struct tty. */ int ttspeedtab(int speed, struct speedtab *table) { - for ( ; table->sp_speed != -1; table++) - if (table->sp_speed == speed) - return (table->sp_code); - return (-1); + for (; table->sp_speed != -1; table++) { + if (table->sp_speed == speed) { + return table->sp_code; + } + } + return -1; } + /* * Set tty hi and low water marks. * * Try to arrange the dynamics so there's about one second * from hi to low water. * + * Locks: Assumes tty_lock() is held prior to calling. */ void ttsetwater(struct tty *tp) @@ -2310,47 +2914,54 @@ ttsetwater(struct tty *tp) int cps; unsigned int x; -#define CLAMP(x, h, l) ((x) > h ? h : ((x) < l) ? l : (x)) + TTY_LOCK_OWNED(tp); /* debug assert */ + +#define CLAMP(x, h, l) ((x) > h ? h : ((x) < l) ? l : (x)) cps = tp->t_ospeed / 10; tp->t_lowat = x = CLAMP(cps / 2, TTMAXLOWAT, TTMINLOWAT); x += cps; x = CLAMP(x, TTMAXHIWAT, TTMINHIWAT); tp->t_hiwat = roundup(x, CBSIZE); -#undef CLAMP +#undef CLAMP } /* ttyinfo has been converted to the MACH kernel */ #include /* XXX Should be in Mach header , but doesn't work */ -extern kern_return_t thread_info_internal(thread_t thread, - thread_flavor_t flavor, - thread_info_t thread_info_out, - mach_msg_type_number_t *thread_info_count); +extern kern_return_t thread_info_internal(thread_t thread, + thread_flavor_t flavor, + thread_info_t thread_info_out, + mach_msg_type_number_t *thread_info_count); + /* * Report on state of foreground process group. + * + * Locks: Assumes tty_lock() is held prior to calling. */ void -ttyinfo(struct tty *tp) +ttyinfo_locked(struct tty *tp) { - int load; - thread_t thread; - uthread_t uthread; - proc_t p; - proc_t pick; + int load; + thread_t thread; + uthread_t uthread; + proc_t p; + proc_t pick; pid_t pickpid; - const char *state; - struct timeval utime; - struct timeval stime; - thread_basic_info_data_t basic_info; - mach_msg_type_number_t mmtn = THREAD_BASIC_INFO_COUNT; + const char *state; + struct timeval utime; + struct timeval stime; + thread_basic_info_data_t basic_info; + mach_msg_type_number_t mmtn = THREAD_BASIC_INFO_COUNT; struct pgrp * pg; + TTY_LOCK_OWNED(tp); /* debug assert */ - if (ttycheckoutq(tp,0) == 0) + if (ttycheckoutq(tp, 0) == 0) { return; + } /* Print load average. */ load = (averunnable.ldavg[0] * 100 + FSCALE / 2) >> FSHIFT; @@ -2364,7 +2975,7 @@ ttyinfo(struct tty *tp) ttyprintf(tp, "not a controlling terminal\n"); tp->t_rocount = 0; return; -} + } if (tp->t_pgrp == NULL) { ttyprintf(tp, "no foreground process group\n"); tp->t_rocount = 0; @@ -2394,11 +3005,15 @@ ttyinfo(struct tty *tp) } } pgrp_unlock(pg); + /* SAFE: All callers drop the lock on return */ + tty_unlock(tp); pg_rele(pg); + tty_lock(tp); pick = proc_find(pickpid); - if (pick == PROC_NULL) + if (pick == PROC_NULL) { return; + } if (TAILQ_EMPTY(&pick->p_uthlist) || (uthread = TAILQ_FIRST(&pick->p_uthlist)) == NULL || @@ -2410,7 +3025,7 @@ ttyinfo(struct tty *tp) return; } - switch(basic_info.run_state) { + switch (basic_info.run_state) { case TH_STATE_RUNNING: state = "running"; break; @@ -2431,18 +3046,20 @@ ttyinfo(struct tty *tp) break; } calcru(pick, &utime, &stime, NULL); - proc_rele(pick); /* Print command, pid, state, utime, and stime */ - ttyprintf(tp, " cmd: %s %d %s %ld.%02ldu %ld.%02lds\n", - pick->p_comm, - pick->p_pid, - state, - (long)utime.tv_sec, utime.tv_usec / 10000, - (long)stime.tv_sec, stime.tv_usec / 10000); + ttyprintf(tp, " cmd: %s %d %s %ld.%02du %ld.%02ds\n", + pick->p_comm, + pick->p_pid, + state, + (long)utime.tv_sec, utime.tv_usec / 10000, + (long)stime.tv_sec, stime.tv_usec / 10000); + + proc_rele(pick); tp->t_rocount = 0; } + /* * Returns 1 if p2 is "better" than p1 * @@ -2455,83 +3072,125 @@ ttyinfo(struct tty *tp) * 3) The sleeper with the shortest sleep time is next. * 4) Further ties are broken by picking the highest pid. */ -#define ISRUN(p) (((p)->p_stat == SRUN) || ((p)->p_stat == SIDL)) +#define ISRUN(p) (((p)->p_stat == SRUN) || ((p)->p_stat == SIDL)) #define TESTAB(a, b) ((a)<<1 | (b)) #define ONLYA 2 #define ONLYB 1 #define BOTH 3 +/* + * Locks: pgrp_lock(p2) held on call to this function + * tty_lock(tp) for p2's tty, for which p2 is the foreground + * process, held on call to this function + */ static int proc_compare(proc_t p1, proc_t p2) { /* NOTE THIS FN needs to be NON BLOCKING */ - if (p1 == NULL) - return (1); + if (p1 == NULL) { + return 1; + } /* * see if at least one of them is runnable */ switch (TESTAB(ISRUN(p1), ISRUN(p2))) { case ONLYA: - return (0); + return 0; case ONLYB: - return (1); + return 1; case BOTH: /* * tie - favor one with highest recent cpu utilization */ #ifdef _PROC_HAS_SCHEDINFO_ /* Without the support the fields are always zero */ - if (p2->p_estcpu > p1->p_estcpu) - return (1); - if (p1->p_estcpu > p2->p_estcpu) - return (0); + if (p2->p_estcpu > p1->p_estcpu) { + return 1; + } + if (p1->p_estcpu > p2->p_estcpu) { + return 0; + } #endif /* _PROC_HAS_SCHEDINFO_ */ - return (p2->p_pid > p1->p_pid); /* tie - return highest pid */ + return p2->p_pid > p1->p_pid; /* tie - return highest pid */ } /* - * weed out zombies + * weed out zombies */ switch (TESTAB(p1->p_stat == SZOMB, p2->p_stat == SZOMB)) { case ONLYA: - return (1); + return 1; case ONLYB: - return (0); + return 0; case BOTH: - return (p2->p_pid > p1->p_pid); /* tie - return highest pid */ + return p2->p_pid > p1->p_pid; /* tie - return highest pid */ } /* * pick the one with the smallest sleep time */ #ifdef _PROC_HAS_SCHEDINFO_ /* Without the support the fields are always zero */ - if (p2->p_slptime > p1->p_slptime) - return (0); - if (p1->p_slptime > p2->p_slptime) - return (1); + if (p2->p_slptime > p1->p_slptime) { + return 0; + } + if (p1->p_slptime > p2->p_slptime) { + return 1; + } #endif /* _PROC_HAS_SCHEDINFO_ */ - return (p2->p_pid > p1->p_pid); /* tie - return highest pid */ + return p2->p_pid > p1->p_pid; /* tie - return highest pid */ } + /* * Output char to tty; console putchar style. + * + * Locks: Assumes tty_lock() is held prior to calling. + * + * Notes: Only ever called from putchar() in subr_prf.c */ int tputchar(int c, struct tty *tp) { + TTY_LOCK_OWNED(tp); /* debug assert */ + if (!ISSET(tp->t_state, TS_CONNECTED)) { - return (-1); + return -1; } - if (c == '\n') + if (c == '\n') { (void)ttyoutput('\r', tp); + } (void)ttyoutput(c, tp); ttstart(tp); - return (0); + return 0; } + /* + * ttysleep + * + * Sleep on a wait channel waiting for an interrupt or a condition to come + * true so that we are woken up. + * + * Parameters: tp Tty going to sleep + * chan The sleep channel (usually an address + * of a structure member) + * pri priority and flags + * wmesg Wait message; shows up in debugger, + * should show up in "ps", but doesn't + * timo Timeout for the sleep + * + * Returns: 0 Condition came true + * ERESTART Upper layer must redrive the call; + * this is usually done by the Libc + * stub in user space + * msleep0:EINTR Interrupted (usually a signal) + * msleep0:ERESTART Interrupted (usually a masked signal) + * msleep0:EWOULDBLOCK Timeout (timo) already expired + * + * Locks: Assumes tty_lock() is held prior to calling. + * * Sleep on chan, returning ERESTART if tty changed while we napped and - * returning any errors (e.g. EINTR/EWOULDBLOCK) reported by tsleep. If + * returning any errors (e.g. EINTR/EWOULDBLOCK) reported by msleep0. If * the tty is revoked, restarting a pending call will redo validation done * at the start of the call. */ @@ -2541,13 +3200,18 @@ ttysleep(struct tty *tp, void *chan, int pri, const char *wmesg, int timo) int error; int gen; + TTY_LOCK_OWNED(tp); + gen = tp->t_gen; - error = tsleep(chan, pri, wmesg, timo); - if (error) - return (error); - return (tp->t_gen == gen ? 0 : ERESTART); + /* Use of msleep0() avoids conversion timo/timespec/timo */ + error = msleep0(chan, &tp->t_lock, pri, wmesg, timo, (int (*)(int))0); + if (error) { + return error; + } + return tp->t_gen == gen ? 0 : ERESTART; } + /* * Allocate a tty structure and its associated buffers. * @@ -2555,42 +3219,97 @@ ttysleep(struct tty *tp, void *chan, int pri, const char *wmesg, int timo) * * Returns: !NULL Address of new struct tty * NULL Error ("ENOMEM") + * + * Locks: The tty_lock() of the returned tty is not held when it + * is returned. */ struct tty * ttymalloc(void) { struct tty *tp; - MALLOC(tp, struct tty *, sizeof(struct tty), M_TTYS, M_WAITOK|M_ZERO); + MALLOC(tp, struct tty *, sizeof(struct tty), M_TTYS, M_WAITOK | M_ZERO); if (tp != NULL) { /* XXX: default to TTYCLSIZE(1024) chars for now */ clalloc(&tp->t_rawq, TTYCLSIZE, 1); clalloc(&tp->t_canq, TTYCLSIZE, 1); /* output queue doesn't need quoting */ clalloc(&tp->t_outq, TTYCLSIZE, 0); + lck_mtx_init(&tp->t_lock, tty_lck_grp, tty_lck_attr); + klist_init(&tp->t_rsel.si_note); + klist_init(&tp->t_wsel.si_note); + tp->t_refcnt = 1; } - return(tp); + return tp; +} + +/* + * Increment the reference count on a tty. + */ +void +ttyhold(struct tty *tp) +{ + TTY_LOCK_OWNED(tp); + tp->t_refcnt++; } /* - * Free a tty structure and its buffers. + * Drops a reference count on a tty structure; if the reference count reaches + * zero, then also frees the structure and associated buffers. */ void ttyfree(struct tty *tp) { + TTY_LOCK_NOTOWNED(tp); + + tty_lock(tp); + if (--tp->t_refcnt == 0) { + tty_unlock(tp); + ttydeallocate(tp); + } else if (tp->t_refcnt < 0) { + panic("%s: freeing free tty %p", __func__, tp); + } else { + tty_unlock(tp); + } +} + +/* + * Deallocate a tty structure and its buffers. + * + * Locks: The tty_lock() is assumed to not be held at the time of + * the free; this function destroys the mutex. + */ +static void +ttydeallocate(struct tty *tp) +{ + TTY_LOCK_NOTOWNED(tp); /* debug assert */ + +#if DEBUG + if (!(SLIST_EMPTY(&tp->t_rsel.si_note) && SLIST_EMPTY(&tp->t_wsel.si_note))) { + panic("knotes hooked into a tty when the tty is freed.\n"); + } +#endif /* DEBUG */ + clfree(&tp->t_rawq); clfree(&tp->t_canq); clfree(&tp->t_outq); + lck_mtx_destroy(&tp->t_lock, tty_lck_grp); FREE(tp, M_TTYS); } + +/* + * Locks: Assumes tty_lock() is held prior to calling. + */ int isbackground(proc_t p, struct tty *tp) { - return (isctty(p, tp) && (p->p_pgrp != tp->t_pgrp)); + TTY_LOCK_OWNED(tp); + + return tp->t_session != NULL && p->p_pgrp != NULL && (p->p_pgrp != tp->t_pgrp) && isctty_sp(p, tp, p->p_pgrp->pg_session); } -static int +static int isctty(proc_t p, struct tty *tp) { int retval; @@ -2599,13 +3318,358 @@ isctty(proc_t p, struct tty *tp) sessp = proc_session(p); retval = (sessp == tp->t_session && p->p_flag & P_CONTROLT); session_rele(sessp); - return(retval); + return retval; } static int isctty_sp(proc_t p, struct tty *tp, struct session *sessp) { - return(sessp == tp->t_session && p->p_flag & P_CONTROLT); + return sessp == tp->t_session && p->p_flag & P_CONTROLT; +} + + +static int filt_ttyattach(struct knote *kn, struct kevent_qos_s *kev); +static void filt_ttydetach(struct knote *kn); +static int filt_ttyevent(struct knote *kn, long hint); +static int filt_ttytouch(struct knote *kn, struct kevent_qos_s *kev); +static int filt_ttyprocess(struct knote *kn, struct kevent_qos_s *kev); + +SECURITY_READ_ONLY_EARLY(struct filterops) tty_filtops = { + .f_isfd = 1, + .f_attach = filt_ttyattach, + .f_detach = filt_ttydetach, + .f_event = filt_ttyevent, + .f_touch = filt_ttytouch, + .f_process = filt_ttyprocess +}; + +/* + * Called with struct tty locked. Returns non-zero if there is data to be read + * or written. + */ +static int +filt_tty_common(struct knote *kn, struct kevent_qos_s *kev, struct tty *tp) +{ + int retval = 0; + int64_t data = 0; + TTY_LOCK_OWNED(tp); /* debug assert */ + + switch (kn->kn_filter) { + case EVFILT_READ: + /* + * ttnread can change the tty state, + * hence must be done upfront, before any other check. + */ + data = ttnread(tp); + retval = (data != 0); + break; + case EVFILT_WRITE: + if ((tp->t_outq.c_cc <= tp->t_lowat) && + (tp->t_state & TS_CONNECTED)) { + data = tp->t_hiwat - tp->t_outq.c_cc; + retval = (data != 0); + } + break; + default: + panic("tty kevent: unexpected filter: %d, kn = %p, tty = %p", + kn->kn_filter, kn, tp); + break; + } + + /* + * TODO(mwidmann, jandrus): For native knote low watermark support, + * check the kn_sfflags for NOTE_LOWAT and check against kn_sdata. + * + * res = ((kn->kn_sfflags & NOTE_LOWAT) != 0) ? + * (kn->kn_data >= kn->kn_sdata) : kn->kn_data; + */ + + if (tp->t_state & TS_ZOMBIE) { + kn->kn_flags |= EV_EOF; + } + if (kn->kn_flags & EV_EOF) { + retval = 1; + } + if (retval && kev) { + knote_fill_kevent(kn, kev, data); + } + + return retval; +} + +/* + * Find the struct tty from a waitq, which is a member of one of the two struct + * selinfos inside the struct tty. Use the seltype to determine which selinfo. + */ +static struct tty * +tty_from_waitq(struct waitq *wq, int seltype) +{ + struct selinfo *si; + struct tty *tp = NULL; + + /* + * The waitq is part of the selinfo structure managed by the driver. For + * certain drivers, we want to hook the knote into the selinfo + * structure's si_note field so selwakeup can call KNOTE. + * + * While 'wq' is not really a queue element, this macro only uses the + * pointer to calculate the offset into a structure given an element + * name. + */ + si = qe_element(wq, struct selinfo, si_waitq); + + /* + * For TTY drivers, the selinfo structure is somewhere in the struct + * tty. There are two different selinfo structures, and the one used + * corresponds to the type of filter requested. + * + * While 'si' is not really a queue element, this macro only uses the + * pointer to calculate the offset into a structure given an element + * name. + */ + switch (seltype) { + case FREAD: + tp = qe_element(si, struct tty, t_rsel); + break; + case FWRITE: + tp = qe_element(si, struct tty, t_wsel); + break; + } + + return tp; } +static struct tty * +tty_from_knote(struct knote *kn) +{ + return (struct tty *)kn->kn_hook; +} + +/* + * Set the knote's struct tty to the kn_hook field. + * + * The idea is to fake a call to select with our own waitq set. If the driver + * calls selrecord, we'll get a link to their waitq and access to the tty + * structure. + * + * Returns -1 on failure, with the error set in the knote, or selres on success. + */ +static int +tty_set_knote_hook(struct knote *kn) +{ + uthread_t uth; + vfs_context_t ctx; + vnode_t vp; + kern_return_t kr; + struct waitq *wq = NULL; + struct waitq_set *old_wqs; + struct waitq_set tmp_wqs; + uint64_t rsvd, rsvd_arg; + uint64_t *rlptr = NULL; + int selres = -1; + struct tty *tp; + + uth = get_bsdthread_info(current_thread()); + + ctx = vfs_context_current(); + vp = (vnode_t)kn->kn_fp->f_fglob->fg_data; + + /* + * Reserve a link element to avoid potential allocation under + * a spinlock. + */ + rsvd = rsvd_arg = waitq_link_reserve(NULL); + rlptr = (void *)&rsvd_arg; + + /* + * Trick selrecord into hooking a known waitq set into the device's selinfo + * waitq. Once the link is in place, we can get back into the selinfo from + * the waitq and subsequently the tty (see tty_from_waitq). + * + * We can't use a real waitq set (such as the kqueue's) because wakeups + * might happen before we can unlink it. + */ + kr = waitq_set_init(&tmp_wqs, SYNC_POLICY_FIFO | SYNC_POLICY_PREPOST, NULL, + NULL); + assert(kr == KERN_SUCCESS); + + /* + * Lazy allocate the waitqset to avoid potential allocation under + * a spinlock; + */ + waitq_set_lazy_init_link(&tmp_wqs); + + old_wqs = uth->uu_wqset; + uth->uu_wqset = &tmp_wqs; + /* + * FMARK forces selects to always call selrecord, even if data is + * available. See ttselect, ptsselect, ptcselect. + * + * selres also contains the data currently available in the tty. + */ + selres = VNOP_SELECT(vp, knote_get_seltype(kn) | FMARK, 0, rlptr, ctx); + uth->uu_wqset = old_wqs; + + /* + * Make sure to cleanup the reserved link - this guards against + * drivers that may not actually call selrecord(). + */ + waitq_link_release(rsvd); + if (rsvd == rsvd_arg) { + /* + * The driver didn't call selrecord -- there's no tty hooked up so we + * can't attach. + */ + knote_set_error(kn, ENOTTY); + selres = -1; + goto out; + } + + /* rlptr may not point to a properly aligned pointer */ + memcpy(&wq, rlptr, sizeof(void *)); + + tp = tty_from_waitq(wq, knote_get_seltype(kn)); + assert(tp != NULL); + + /* + * Take a reference and stash the tty in the knote. + */ + tty_lock(tp); + ttyhold(tp); + kn->kn_hook = tp; + tty_unlock(tp); + +out: + /* + * Cleaning up the wqset will unlink its waitq and clean up any preposts + * that occurred as a result of data coming in while the tty was attached. + */ + waitq_set_deinit(&tmp_wqs); + + return selres; +} + +static int +filt_ttyattach(struct knote *kn, __unused struct kevent_qos_s *kev) +{ + int selres = 0; + struct tty *tp; + + /* + * This function should be called from filt_specattach (spec_vnops.c), + * so most of the knote data structure should already be initialized. + */ + + /* don't support offsets in ttys or drivers that don't use struct tty */ + if (kn->kn_vnode_use_ofst || !kn->kn_vnode_kqok) { + knote_set_error(kn, ENOTSUP); + return 0; + } + + /* + * Connect the struct tty to the knote through the selinfo structure + * referenced by the waitq within the selinfo. + */ + selres = tty_set_knote_hook(kn); + if (selres < 0) { + return 0; + } + + /* + * Attach the knote to selinfo's klist. + */ + tp = tty_from_knote(kn); + tty_lock(tp); + + switch (kn->kn_filter) { + case EVFILT_READ: + KNOTE_ATTACH(&tp->t_rsel.si_note, kn); + break; + case EVFILT_WRITE: + KNOTE_ATTACH(&tp->t_wsel.si_note, kn); + break; + default: + panic("invalid knote %p attach, filter: %d", kn, kn->kn_filter); + } + + tty_unlock(tp); + + return selres; +} + +static void +filt_ttydetach(struct knote *kn) +{ + struct tty *tp = tty_from_knote(kn); + + tty_lock(tp); + + switch (kn->kn_filter) { + case EVFILT_READ: + KNOTE_DETACH(&tp->t_rsel.si_note, kn); + break; + case EVFILT_WRITE: + KNOTE_DETACH(&tp->t_wsel.si_note, kn); + break; + default: + panic("invalid knote %p detach, filter: %d", kn, kn->kn_filter); + break; + } + + tty_unlock(tp); + ttyfree(tp); +} + +static int +filt_ttyevent(struct knote *kn, long hint) +{ + struct tty *tp = tty_from_knote(kn); + int ret; + + TTY_LOCK_OWNED(tp); + + if (hint & NOTE_REVOKE) { + kn->kn_flags |= EV_EOF | EV_ONESHOT; + ret = 1; + } else { + ret = filt_tty_common(kn, NULL, tp); + } + + return ret; +} + +static int +filt_ttytouch(struct knote *kn, struct kevent_qos_s *kev) +{ + struct tty *tp = tty_from_knote(kn); + int res = 0; + + tty_lock(tp); + + kn->kn_sdata = kev->data; + kn->kn_sfflags = kev->fflags; + + if (kn->kn_vnode_kqok) { + res = filt_tty_common(kn, NULL, tp); + } + + tty_unlock(tp); + + return res; +} + +static int +filt_ttyprocess(struct knote *kn, struct kevent_qos_s *kev) +{ + struct tty *tp = tty_from_knote(kn); + int res; + + tty_lock(tp); + + res = filt_tty_common(kn, kev, tp); + + tty_unlock(tp); + + return res; +}