Index: head/sys/kern/tty_inq.c =================================================================== --- head/sys/kern/tty_inq.c (revision 333849) +++ head/sys/kern/tty_inq.c (revision 333850) @@ -1,499 +1,497 @@ /*- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * * Copyright (c) 2008 Ed Schouten * All rights reserved. * * Portions of this software were developed under sponsorship from Snow * B.V., the Netherlands. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include /* * TTY input queue buffering. * * Unlike the output queue, the input queue has more features that are * needed to properly implement various features offered by the TTY * interface: * * - Data can be removed from the tail of the queue, which is used to * implement backspace. * - Once in a while, input has to be `canonicalized'. When ICANON is * turned on, this will be done after a CR has been inserted. * Otherwise, it should be done after any character has been inserted. * - The input queue can store one bit per byte, called the quoting bit. * This bit is used by TTYDISC to make backspace work on quoted * characters. * * In most cases, there is probably less input than output, so unlike * the outq, we'll stick to 128 byte blocks here. */ static int ttyinq_flush_secure = 1; SYSCTL_INT(_kern, OID_AUTO, tty_inq_flush_secure, CTLFLAG_RW, &ttyinq_flush_secure, 0, "Zero buffers while flushing"); #define TTYINQ_QUOTESIZE (TTYINQ_DATASIZE / BMSIZE) #define BMSIZE 32 #define GETBIT(tib,boff) \ ((tib)->tib_quotes[(boff) / BMSIZE] & (1 << ((boff) % BMSIZE))) #define SETBIT(tib,boff) \ ((tib)->tib_quotes[(boff) / BMSIZE] |= (1 << ((boff) % BMSIZE))) #define CLRBIT(tib,boff) \ ((tib)->tib_quotes[(boff) / BMSIZE] &= ~(1 << ((boff) % BMSIZE))) struct ttyinq_block { struct ttyinq_block *tib_prev; struct ttyinq_block *tib_next; uint32_t tib_quotes[TTYINQ_QUOTESIZE]; char tib_data[TTYINQ_DATASIZE]; }; static uma_zone_t ttyinq_zone; #define TTYINQ_INSERT_TAIL(ti, tib) do { \ if (ti->ti_end == 0) { \ tib->tib_prev = NULL; \ tib->tib_next = ti->ti_firstblock; \ ti->ti_firstblock = tib; \ } else { \ tib->tib_prev = ti->ti_lastblock; \ tib->tib_next = ti->ti_lastblock->tib_next; \ ti->ti_lastblock->tib_next = tib; \ } \ if (tib->tib_next != NULL) \ tib->tib_next->tib_prev = tib; \ ti->ti_nblocks++; \ } while (0) #define TTYINQ_REMOVE_HEAD(ti) do { \ ti->ti_firstblock = ti->ti_firstblock->tib_next; \ if (ti->ti_firstblock != NULL) \ ti->ti_firstblock->tib_prev = NULL; \ ti->ti_nblocks--; \ } while (0) #define TTYINQ_RECYCLE(ti, tib) do { \ if (ti->ti_quota <= ti->ti_nblocks) \ uma_zfree(ttyinq_zone, tib); \ else \ TTYINQ_INSERT_TAIL(ti, tib); \ } while (0) int ttyinq_setsize(struct ttyinq *ti, struct tty *tp, size_t size) { struct ttyinq_block *tib; ti->ti_quota = howmany(size, TTYINQ_DATASIZE); while (ti->ti_quota > ti->ti_nblocks) { /* * List is getting bigger. * Add new blocks to the tail of the list. * * We must unlock the TTY temporarily, because we need * to allocate memory. This won't be a problem, because * in the worst case, another thread ends up here, which * may cause us to allocate too many blocks, but this * will be caught by the loop below. */ tty_unlock(tp); tib = uma_zalloc(ttyinq_zone, M_WAITOK); tty_lock(tp); if (tty_gone(tp)) { uma_zfree(ttyinq_zone, tib); return (ENXIO); } TTYINQ_INSERT_TAIL(ti, tib); } return (0); } void ttyinq_free(struct ttyinq *ti) { struct ttyinq_block *tib; ttyinq_flush(ti); ti->ti_quota = 0; while ((tib = ti->ti_firstblock) != NULL) { TTYINQ_REMOVE_HEAD(ti); uma_zfree(ttyinq_zone, tib); } MPASS(ti->ti_nblocks == 0); } int ttyinq_read_uio(struct ttyinq *ti, struct tty *tp, struct uio *uio, size_t rlen, size_t flen) { MPASS(rlen <= uio->uio_resid); while (rlen > 0) { int error; struct ttyinq_block *tib; size_t cbegin, cend, clen; /* See if there still is data. */ if (ti->ti_begin == ti->ti_linestart) return (0); tib = ti->ti_firstblock; if (tib == NULL) return (0); /* * The end address should be the lowest of these three: * - The write pointer * - The blocksize - we can't read beyond the block * - The end address if we could perform the full read */ cbegin = ti->ti_begin; cend = MIN(MIN(ti->ti_linestart, ti->ti_begin + rlen), TTYINQ_DATASIZE); clen = cend - cbegin; MPASS(clen >= flen); rlen -= clen; /* * We can prevent buffering in some cases: * - We need to read the block until the end. * - We don't need to read the block until the end, but * there is no data beyond it, which allows us to move * the write pointer to a new block. */ if (cend == TTYINQ_DATASIZE || cend == ti->ti_end) { /* * Fast path: zero copy. Remove the first block, * so we can unlock the TTY temporarily. */ TTYINQ_REMOVE_HEAD(ti); ti->ti_begin = 0; /* * Because we remove the first block, we must * fix up the block offsets. */ #define CORRECT_BLOCK(t) do { \ if (t <= TTYINQ_DATASIZE) \ t = 0; \ else \ t -= TTYINQ_DATASIZE; \ } while (0) CORRECT_BLOCK(ti->ti_linestart); CORRECT_BLOCK(ti->ti_reprint); CORRECT_BLOCK(ti->ti_end); #undef CORRECT_BLOCK /* * Temporary unlock and copy the data to * userspace. We may need to flush trailing * bytes, like EOF characters. */ tty_unlock(tp); error = uiomove(tib->tib_data + cbegin, clen - flen, uio); tty_lock(tp); /* Block can now be readded to the list. */ TTYINQ_RECYCLE(ti, tib); } else { char ob[TTYINQ_DATASIZE - 1]; /* * Slow path: store data in a temporary buffer. */ memcpy(ob, tib->tib_data + cbegin, clen - flen); ti->ti_begin += clen; MPASS(ti->ti_begin < TTYINQ_DATASIZE); /* Temporary unlock and copy the data to userspace. */ tty_unlock(tp); error = uiomove(ob, clen - flen, uio); tty_lock(tp); } if (error != 0) return (error); if (tty_gone(tp)) return (ENXIO); } return (0); } static __inline void ttyinq_set_quotes(struct ttyinq_block *tib, size_t offset, size_t length, int value) { if (value) { /* Set the bits. */ for (; length > 0; length--, offset++) SETBIT(tib, offset); } else { /* Unset the bits. */ for (; length > 0; length--, offset++) CLRBIT(tib, offset); } } size_t ttyinq_write(struct ttyinq *ti, const void *buf, size_t nbytes, int quote) { const char *cbuf = buf; struct ttyinq_block *tib; unsigned int boff; size_t l; while (nbytes > 0) { boff = ti->ti_end % TTYINQ_DATASIZE; if (ti->ti_end == 0) { /* First time we're being used or drained. */ MPASS(ti->ti_begin == 0); tib = ti->ti_firstblock; if (tib == NULL) { /* Queue has no blocks. */ break; } ti->ti_lastblock = tib; } else if (boff == 0) { /* We reached the end of this block on last write. */ tib = ti->ti_lastblock->tib_next; if (tib == NULL) { /* We've reached the watermark. */ break; } ti->ti_lastblock = tib; } else { tib = ti->ti_lastblock; } /* Don't copy more than was requested. */ l = MIN(nbytes, TTYINQ_DATASIZE - boff); MPASS(l > 0); memcpy(tib->tib_data + boff, cbuf, l); /* Set the quoting bits for the proper region. */ ttyinq_set_quotes(tib, boff, l, quote); cbuf += l; nbytes -= l; ti->ti_end += l; } return (cbuf - (const char *)buf); } int ttyinq_write_nofrag(struct ttyinq *ti, const void *buf, size_t nbytes, int quote) { -#ifdef INVARIANTS - size_t ret; -#endif + size_t ret __unused; if (ttyinq_bytesleft(ti) < nbytes) return (-1); /* We should always be able to write it back. */ - DBGSET(ret, ttyinq_write(ti, buf, nbytes, quote)); + ret = ttyinq_write(ti, buf, nbytes, quote); MPASS(ret == nbytes); return (0); } void ttyinq_canonicalize(struct ttyinq *ti) { ti->ti_linestart = ti->ti_reprint = ti->ti_end; ti->ti_startblock = ti->ti_reprintblock = ti->ti_lastblock; } size_t ttyinq_findchar(struct ttyinq *ti, const char *breakc, size_t maxlen, char *lastc) { struct ttyinq_block *tib = ti->ti_firstblock; unsigned int boff = ti->ti_begin; unsigned int bend = MIN(MIN(TTYINQ_DATASIZE, ti->ti_linestart), ti->ti_begin + maxlen); MPASS(maxlen > 0); if (tib == NULL) return (0); while (boff < bend) { if (strchr(breakc, tib->tib_data[boff]) && !GETBIT(tib, boff)) { *lastc = tib->tib_data[boff]; return (boff - ti->ti_begin + 1); } boff++; } /* Not found - just process the entire block. */ return (bend - ti->ti_begin); } void ttyinq_flush(struct ttyinq *ti) { struct ttyinq_block *tib; ti->ti_begin = 0; ti->ti_linestart = 0; ti->ti_reprint = 0; ti->ti_end = 0; /* Zero all data in the input queue to get rid of passwords. */ if (ttyinq_flush_secure) { for (tib = ti->ti_firstblock; tib != NULL; tib = tib->tib_next) bzero(&tib->tib_data, sizeof tib->tib_data); } } int ttyinq_peekchar(struct ttyinq *ti, char *c, int *quote) { unsigned int boff; struct ttyinq_block *tib = ti->ti_lastblock; if (ti->ti_linestart == ti->ti_end) return (-1); MPASS(ti->ti_end > 0); boff = (ti->ti_end - 1) % TTYINQ_DATASIZE; *c = tib->tib_data[boff]; *quote = GETBIT(tib, boff); return (0); } void ttyinq_unputchar(struct ttyinq *ti) { MPASS(ti->ti_linestart < ti->ti_end); if (--ti->ti_end % TTYINQ_DATASIZE == 0) { /* Roll back to the previous block. */ ti->ti_lastblock = ti->ti_lastblock->tib_prev; /* * This can only fail if we are unputchar()'ing the * first character in the queue. */ MPASS((ti->ti_lastblock == NULL) == (ti->ti_end == 0)); } } void ttyinq_reprintpos_set(struct ttyinq *ti) { ti->ti_reprint = ti->ti_end; ti->ti_reprintblock = ti->ti_lastblock; } void ttyinq_reprintpos_reset(struct ttyinq *ti) { ti->ti_reprint = ti->ti_linestart; ti->ti_reprintblock = ti->ti_startblock; } static void ttyinq_line_iterate(struct ttyinq *ti, ttyinq_line_iterator_t *iterator, void *data, unsigned int offset, struct ttyinq_block *tib) { unsigned int boff; /* Use the proper block when we're at the queue head. */ if (offset == 0) tib = ti->ti_firstblock; /* Iterate all characters and call the iterator function. */ for (; offset < ti->ti_end; offset++) { boff = offset % TTYINQ_DATASIZE; MPASS(tib != NULL); /* Call back the iterator function. */ iterator(data, tib->tib_data[boff], GETBIT(tib, boff)); /* Last byte iterated - go to the next block. */ if (boff == TTYINQ_DATASIZE - 1) tib = tib->tib_next; MPASS(tib != NULL); } } void ttyinq_line_iterate_from_linestart(struct ttyinq *ti, ttyinq_line_iterator_t *iterator, void *data) { ttyinq_line_iterate(ti, iterator, data, ti->ti_linestart, ti->ti_startblock); } void ttyinq_line_iterate_from_reprintpos(struct ttyinq *ti, ttyinq_line_iterator_t *iterator, void *data) { ttyinq_line_iterate(ti, iterator, data, ti->ti_reprint, ti->ti_reprintblock); } static void ttyinq_startup(void *dummy) { ttyinq_zone = uma_zcreate("ttyinq", sizeof(struct ttyinq_block), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); } SYSINIT(ttyinq, SI_SUB_DRIVERS, SI_ORDER_FIRST, ttyinq_startup, NULL); Index: head/sys/kern/tty_outq.c =================================================================== --- head/sys/kern/tty_outq.c (revision 333849) +++ head/sys/kern/tty_outq.c (revision 333850) @@ -1,349 +1,347 @@ /*- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * * Copyright (c) 2008 Ed Schouten * All rights reserved. * * Portions of this software were developed under sponsorship from Snow * B.V., the Netherlands. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include /* * TTY output queue buffering. * * The previous design of the TTY layer offered the so-called clists. * These clists were used for both the input queues and the output * queue. We don't use certain features on the output side, like quoting * bits for parity marking and such. This mechanism is similar to the * old clists, but only contains the features we need to buffer the * output. */ struct ttyoutq_block { struct ttyoutq_block *tob_next; char tob_data[TTYOUTQ_DATASIZE]; }; static uma_zone_t ttyoutq_zone; #define TTYOUTQ_INSERT_TAIL(to, tob) do { \ if (to->to_end == 0) { \ tob->tob_next = to->to_firstblock; \ to->to_firstblock = tob; \ } else { \ tob->tob_next = to->to_lastblock->tob_next; \ to->to_lastblock->tob_next = tob; \ } \ to->to_nblocks++; \ } while (0) #define TTYOUTQ_REMOVE_HEAD(to) do { \ to->to_firstblock = to->to_firstblock->tob_next; \ to->to_nblocks--; \ } while (0) #define TTYOUTQ_RECYCLE(to, tob) do { \ if (to->to_quota <= to->to_nblocks) \ uma_zfree(ttyoutq_zone, tob); \ else \ TTYOUTQ_INSERT_TAIL(to, tob); \ } while(0) void ttyoutq_flush(struct ttyoutq *to) { to->to_begin = 0; to->to_end = 0; } int ttyoutq_setsize(struct ttyoutq *to, struct tty *tp, size_t size) { struct ttyoutq_block *tob; to->to_quota = howmany(size, TTYOUTQ_DATASIZE); while (to->to_quota > to->to_nblocks) { /* * List is getting bigger. * Add new blocks to the tail of the list. * * We must unlock the TTY temporarily, because we need * to allocate memory. This won't be a problem, because * in the worst case, another thread ends up here, which * may cause us to allocate too many blocks, but this * will be caught by the loop below. */ tty_unlock(tp); tob = uma_zalloc(ttyoutq_zone, M_WAITOK); tty_lock(tp); if (tty_gone(tp)) { uma_zfree(ttyoutq_zone, tob); return (ENXIO); } TTYOUTQ_INSERT_TAIL(to, tob); } return (0); } void ttyoutq_free(struct ttyoutq *to) { struct ttyoutq_block *tob; ttyoutq_flush(to); to->to_quota = 0; while ((tob = to->to_firstblock) != NULL) { TTYOUTQ_REMOVE_HEAD(to); uma_zfree(ttyoutq_zone, tob); } MPASS(to->to_nblocks == 0); } size_t ttyoutq_read(struct ttyoutq *to, void *buf, size_t len) { char *cbuf = buf; while (len > 0) { struct ttyoutq_block *tob; size_t cbegin, cend, clen; /* See if there still is data. */ if (to->to_begin == to->to_end) break; tob = to->to_firstblock; if (tob == NULL) break; /* * The end address should be the lowest of these three: * - The write pointer * - The blocksize - we can't read beyond the block * - The end address if we could perform the full read */ cbegin = to->to_begin; cend = MIN(MIN(to->to_end, to->to_begin + len), TTYOUTQ_DATASIZE); clen = cend - cbegin; /* Copy the data out of the buffers. */ memcpy(cbuf, tob->tob_data + cbegin, clen); cbuf += clen; len -= clen; if (cend == to->to_end) { /* Read the complete queue. */ to->to_begin = 0; to->to_end = 0; } else if (cend == TTYOUTQ_DATASIZE) { /* Read the block until the end. */ TTYOUTQ_REMOVE_HEAD(to); to->to_begin = 0; to->to_end -= TTYOUTQ_DATASIZE; TTYOUTQ_RECYCLE(to, tob); } else { /* Read the block partially. */ to->to_begin += clen; } } return (cbuf - (char *)buf); } /* * An optimized version of ttyoutq_read() which can be used in pseudo * TTY drivers to directly copy data from the outq to userspace, instead * of buffering it. * * We can only copy data directly if we need to read the entire block * back to the user, because we temporarily remove the block from the * queue. Otherwise we need to copy it to a temporary buffer first, to * make sure data remains in the correct order. */ int ttyoutq_read_uio(struct ttyoutq *to, struct tty *tp, struct uio *uio) { while (uio->uio_resid > 0) { int error; struct ttyoutq_block *tob; size_t cbegin, cend, clen; /* See if there still is data. */ if (to->to_begin == to->to_end) return (0); tob = to->to_firstblock; if (tob == NULL) return (0); /* * The end address should be the lowest of these three: * - The write pointer * - The blocksize - we can't read beyond the block * - The end address if we could perform the full read */ cbegin = to->to_begin; cend = MIN(MIN(to->to_end, to->to_begin + uio->uio_resid), TTYOUTQ_DATASIZE); clen = cend - cbegin; /* * We can prevent buffering in some cases: * - We need to read the block until the end. * - We don't need to read the block until the end, but * there is no data beyond it, which allows us to move * the write pointer to a new block. */ if (cend == TTYOUTQ_DATASIZE || cend == to->to_end) { /* * Fast path: zero copy. Remove the first block, * so we can unlock the TTY temporarily. */ TTYOUTQ_REMOVE_HEAD(to); to->to_begin = 0; if (to->to_end <= TTYOUTQ_DATASIZE) to->to_end = 0; else to->to_end -= TTYOUTQ_DATASIZE; /* Temporary unlock and copy the data to userspace. */ tty_unlock(tp); error = uiomove(tob->tob_data + cbegin, clen, uio); tty_lock(tp); /* Block can now be readded to the list. */ TTYOUTQ_RECYCLE(to, tob); } else { char ob[TTYOUTQ_DATASIZE - 1]; /* * Slow path: store data in a temporary buffer. */ memcpy(ob, tob->tob_data + cbegin, clen); to->to_begin += clen; MPASS(to->to_begin < TTYOUTQ_DATASIZE); /* Temporary unlock and copy the data to userspace. */ tty_unlock(tp); error = uiomove(ob, clen, uio); tty_lock(tp); } if (error != 0) return (error); } return (0); } size_t ttyoutq_write(struct ttyoutq *to, const void *buf, size_t nbytes) { const char *cbuf = buf; struct ttyoutq_block *tob; unsigned int boff; size_t l; while (nbytes > 0) { boff = to->to_end % TTYOUTQ_DATASIZE; if (to->to_end == 0) { /* First time we're being used or drained. */ MPASS(to->to_begin == 0); tob = to->to_firstblock; if (tob == NULL) { /* Queue has no blocks. */ break; } to->to_lastblock = tob; } else if (boff == 0) { /* We reached the end of this block on last write. */ tob = to->to_lastblock->tob_next; if (tob == NULL) { /* We've reached the watermark. */ break; } to->to_lastblock = tob; } else { tob = to->to_lastblock; } /* Don't copy more than was requested. */ l = MIN(nbytes, TTYOUTQ_DATASIZE - boff); MPASS(l > 0); memcpy(tob->tob_data + boff, cbuf, l); cbuf += l; nbytes -= l; to->to_end += l; } return (cbuf - (const char *)buf); } int ttyoutq_write_nofrag(struct ttyoutq *to, const void *buf, size_t nbytes) { -#ifdef INVARIANTS - size_t ret; -#endif + size_t ret __unused; if (ttyoutq_bytesleft(to) < nbytes) return (-1); /* We should always be able to write it back. */ - DBGSET(ret, ttyoutq_write(to, buf, nbytes)); + ret = ttyoutq_write(to, buf, nbytes); MPASS(ret == nbytes); return (0); } static void ttyoutq_startup(void *dummy) { ttyoutq_zone = uma_zcreate("ttyoutq", sizeof(struct ttyoutq_block), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); } SYSINIT(ttyoutq, SI_SUB_DRIVERS, SI_ORDER_FIRST, ttyoutq_startup, NULL);