Rename `tty_subr.c' to `subr_clist.c'.

Because clists are also used outside the TTY layer, rename the file
containing the clist routines to something more accurate.

The mpsafetty TTY layer doesn't use clists. It uses its own buffers,
which also implement the unbuffered copying to userspace. We cannot
simply remove the clist routines then, because this would break various
drivers that are present within the kernel.

Approved by:	philip (mentor)

2 files changed, 1 insertions, 700 deletions

diff --git a/sys/conf/files b/sys/conf/files
index f3bf976..9ede3b8 100644
--- a/sys/conf/files
+++ b/sys/conf/files
@@ -1608,6 +1608,7 @@ kern/subr_acl_posix1e.c		standard
 kern/subr_autoconf.c		standard
 kern/subr_blist.c		standard
 kern/subr_bus.c			standard
+kern/subr_clist.c		standard
 kern/subr_clock.c		standard
 kern/subr_devstat.c		standard
 kern/subr_disk.c		standard
@@ -1655,7 +1656,6 @@ kern/tty_conf.c			standard
 kern/tty_cons.c			standard
 kern/tty_pts.c			optional pty
 kern/tty_pty.c			optional pty
-kern/tty_subr.c			standard
 kern/tty_tty.c			standard
 kern/uipc_accf.c		optional inet
 kern/uipc_cow.c			optional zero_copy_sockets
diff --git a/sys/kern/tty_subr.c b/sys/kern/tty_subr.c
deleted file mode 100644
index 57225db..0000000
--- a/sys/kern/tty_subr.c
+++ /dev/null
@@ -1,699 +0,0 @@
-/*-
- * Copyright (c) 1994, David Greenman
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice unmodified, 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.
- */
-
-/*
- * clist support routines
- */
-
-#include <sys/cdefs.h>
-__FBSDID("$FreeBSD$");
-
-#include <sys/param.h>
-#include <sys/kernel.h>
-#include <sys/systm.h>
-#include <sys/malloc.h>
-#include <sys/tty.h>
-#include <sys/clist.h>
-
-static void clist_init(void *);
-SYSINIT(clist, SI_SUB_CLIST, SI_ORDER_FIRST, clist_init, NULL);
-
-static MALLOC_DEFINE(M_CLIST, "clist", "clist queue blocks");
-
-static struct cblock *cfreelist = 0;
-int cfreecount = 0;
-static int cslushcount;
-static int ctotcount;
-
-#ifndef INITIAL_CBLOCKS
-#define	INITIAL_CBLOCKS 50
-#endif
-
-static struct cblock *cblock_alloc(void);
-static void cblock_alloc_cblocks(int number);
-static void cblock_free(struct cblock *cblockp);
-static void cblock_free_cblocks(int number);
-
-#include "opt_ddb.h"
-#ifdef DDB
-#include <ddb/ddb.h>
-
-DB_SHOW_COMMAND(cbstat, cbstat)
-{
-	int cbsize = CBSIZE;
-
-	printf(
-	"tot = %d (active = %d, free = %d (reserved = %d, slush = %d))\n",
-	       ctotcount * cbsize, ctotcount * cbsize - cfreecount, cfreecount,
-	       cfreecount - cslushcount * cbsize, cslushcount * cbsize);
-}
-#endif /* DDB */
-
-/*
- * Called from init_main.c
- */
-/* ARGSUSED*/
-static void
-clist_init(dummy)
-	void *dummy;
-{
-	/*
-	 * Allocate an initial base set of cblocks as a 'slush'.
-	 * We allocate non-slush cblocks with each initial tty_open() and
-	 * deallocate them with each tty_close().
-	 * We should adjust the slush allocation.  This can't be done in
-	 * the i/o routines because they are sometimes called from
-	 * interrupt handlers when it may be unsafe to call malloc().
-	 */
-	cblock_alloc_cblocks(cslushcount = INITIAL_CBLOCKS);
-}
-
-/*
- * Remove a cblock from the cfreelist queue and return a pointer
- * to it.
- */
-static __inline struct cblock *
-cblock_alloc()
-{
-	struct cblock *cblockp;
-
-	cblockp = cfreelist;
-	if (cblockp == NULL)
-		panic("clist reservation botch");
-	cfreelist = cblockp->c_next;
-	cblockp->c_next = NULL;
-	cfreecount -= CBSIZE;
-	return (cblockp);
-}
-
-/*
- * Add a cblock to the cfreelist queue.
- */
-static __inline void
-cblock_free(cblockp)
-	struct cblock *cblockp;
-{
-	if (isset(cblockp->c_quote, CBQSIZE * NBBY - 1))
-		bzero(cblockp->c_quote, sizeof cblockp->c_quote);
-	cblockp->c_next = cfreelist;
-	cfreelist = cblockp;
-	cfreecount += CBSIZE;
-}
-
-/*
- * Allocate some cblocks for the cfreelist queue.
- */
-static void
-cblock_alloc_cblocks(number)
-	int number;
-{
-	int i;
-	struct cblock *cbp;
-
-	for (i = 0; i < number; ++i) {
-		cbp = malloc(sizeof *cbp, M_CLIST, M_NOWAIT);
-		if (cbp == NULL) {
-			printf(
-"cblock_alloc_cblocks: M_NOWAIT malloc failed, trying M_WAITOK\n");
-			cbp = malloc(sizeof *cbp, M_CLIST, M_WAITOK);
-		}
-		/*
-		 * Freed cblocks have zero quotes and garbage elsewhere.
-		 * Set the may-have-quote bit to force zeroing the quotes.
-		 */
-		setbit(cbp->c_quote, CBQSIZE * NBBY - 1);
-		cblock_free(cbp);
-	}
-	ctotcount += number;
-}
-
-/*
- * Set the cblock allocation policy for a clist.
- * Must be called in process context at spltty().
- */
-void
-clist_alloc_cblocks(clistp, ccmax, ccreserved)
-	struct clist *clistp;
-	int ccmax;
-	int ccreserved;
-{
-	int dcbr;
-
-	/*
-	 * Allow for wasted space at the head.
-	 */
-	if (ccmax != 0)
-		ccmax += CBSIZE - 1;
-	if (ccreserved != 0)
-		ccreserved += CBSIZE - 1;
-
-	clistp->c_cbmax = roundup(ccmax, CBSIZE) / CBSIZE;
-	dcbr = roundup(ccreserved, CBSIZE) / CBSIZE - clistp->c_cbreserved;
-	if (dcbr >= 0)
-		cblock_alloc_cblocks(dcbr);
-	else {
-		if (clistp->c_cbreserved + dcbr < clistp->c_cbcount)
-			dcbr = clistp->c_cbcount - clistp->c_cbreserved;
-		cblock_free_cblocks(-dcbr);
-	}
-	clistp->c_cbreserved += dcbr;
-}
-
-/*
- * Free some cblocks from the cfreelist queue back to the
- * system malloc pool.
- */
-static void
-cblock_free_cblocks(number)
-	int number;
-{
-	int i;
-
-	for (i = 0; i < number; ++i)
-		free(cblock_alloc(), M_CLIST);
-	ctotcount -= number;
-}
-
-/*
- * Free the cblocks reserved for a clist.
- * Must be called at spltty().
- */
-void
-clist_free_cblocks(clistp)
-	struct clist *clistp;
-{
-	if (clistp->c_cbcount != 0)
-		panic("freeing active clist cblocks");
-	cblock_free_cblocks(clistp->c_cbreserved);
-	clistp->c_cbmax = 0;
-	clistp->c_cbreserved = 0;
-}
-
-/*
- * Get a character from the head of a clist.
- */
-int
-getc(clistp)
-	struct clist *clistp;
-{
-	int chr = -1;
-	int s;
-	struct cblock *cblockp;
-
-	s = spltty();
-
-	/* If there are characters in the list, get one */
-	if (clistp->c_cc) {
-		cblockp = (struct cblock *)((intptr_t)clistp->c_cf & ~CROUND);
-		chr = (u_char)*clistp->c_cf;
-
-		/*
-		 * If this char is quoted, set the flag.
-		 */
-		if (isset(cblockp->c_quote, clistp->c_cf - (char *)cblockp->c_info))
-			chr |= TTY_QUOTE;
-
-		/*
-		 * Advance to next character.
-		 */
-		clistp->c_cf++;
-		clistp->c_cc--;
-		/*
-		 * If we have advanced the 'first' character pointer
-		 * past the end of this cblock, advance to the next one.
-		 * If there are no more characters, set the first and
-		 * last pointers to NULL. In either case, free the
-		 * current cblock.
-		 */
-		if ((clistp->c_cf >= (char *)(cblockp+1)) || (clistp->c_cc == 0)) {
-			if (clistp->c_cc > 0) {
-				clistp->c_cf = cblockp->c_next->c_info;
-			} else {
-				clistp->c_cf = clistp->c_cl = NULL;
-			}
-			cblock_free(cblockp);
-			if (--clistp->c_cbcount >= clistp->c_cbreserved)
-				++cslushcount;
-		}
-	}
-
-	splx(s);
-	return (chr);
-}
-
-/*
- * Copy 'amount' of chars, beginning at head of clist 'clistp' to
- * destination linear buffer 'dest'. Return number of characters
- * actually copied.
- */
-int
-q_to_b(clistp, dest, amount)
-	struct clist *clistp;
-	char *dest;
-	int amount;
-{
-	struct cblock *cblockp;
-	struct cblock *cblockn;
-	char *dest_orig = dest;
-	int numc;
-	int s;
-
-	s = spltty();
-
-	while (clistp && amount && (clistp->c_cc > 0)) {
-		cblockp = (struct cblock *)((intptr_t)clistp->c_cf & ~CROUND);
-		cblockn = cblockp + 1; /* pointer arithmetic! */
-		numc = min(amount, (char *)cblockn - clistp->c_cf);
-		numc = min(numc, clistp->c_cc);
-		bcopy(clistp->c_cf, dest, numc);
-		amount -= numc;
-		clistp->c_cf += numc;
-		clistp->c_cc -= numc;
-		dest += numc;
-		/*
-		 * If this cblock has been emptied, advance to the next
-		 * one. If there are no more characters, set the first
-		 * and last pointer to NULL. In either case, free the
-		 * current cblock.
-		 */
-		if ((clistp->c_cf >= (char *)cblockn) || (clistp->c_cc == 0)) {
-			if (clistp->c_cc > 0) {
-				clistp->c_cf = cblockp->c_next->c_info;
-			} else {
-				clistp->c_cf = clistp->c_cl = NULL;
-			}
-			cblock_free(cblockp);
-			if (--clistp->c_cbcount >= clistp->c_cbreserved)
-				++cslushcount;
-		}
-	}
-
-	splx(s);
-	return (dest - dest_orig);
-}
-
-/*
- * Flush 'amount' of chars, beginning at head of clist 'clistp'.
- */
-void
-ndflush(clistp, amount)
-	struct clist *clistp;
-	int amount;
-{
-	struct cblock *cblockp;
-	struct cblock *cblockn;
-	int numc;
-	int s;
-
-	s = spltty();
-
-	while (amount && (clistp->c_cc > 0)) {
-		cblockp = (struct cblock *)((intptr_t)clistp->c_cf & ~CROUND);
-		cblockn = cblockp + 1; /* pointer arithmetic! */
-		numc = min(amount, (char *)cblockn - clistp->c_cf);
-		numc = min(numc, clistp->c_cc);
-		amount -= numc;
-		clistp->c_cf += numc;
-		clistp->c_cc -= numc;
-		/*
-		 * If this cblock has been emptied, advance to the next
-		 * one. If there are no more characters, set the first
-		 * and last pointer to NULL. In either case, free the
-		 * current cblock.
-		 */
-		if ((clistp->c_cf >= (char *)cblockn) || (clistp->c_cc == 0)) {
-			if (clistp->c_cc > 0) {
-				clistp->c_cf = cblockp->c_next->c_info;
-			} else {
-				clistp->c_cf = clistp->c_cl = NULL;
-			}
-			cblock_free(cblockp);
-			if (--clistp->c_cbcount >= clistp->c_cbreserved)
-				++cslushcount;
-		}
-	}
-
-	splx(s);
-}
-
-/*
- * Add a character to the end of a clist. Return -1 is no
- * more clists, or 0 for success.
- */
-int
-putc(chr, clistp)
-	int chr;
-	struct clist *clistp;
-{
-	struct cblock *cblockp;
-	int s;
-
-	s = spltty();
-
-	if (clistp->c_cl == NULL) {
-		if (clistp->c_cbreserved < 1) {
-			splx(s);
-			printf("putc to a clist with no reserved cblocks\n");
-			return (-1);		/* nothing done */
-		}
-		cblockp = cblock_alloc();
-		clistp->c_cbcount = 1;
-		clistp->c_cf = clistp->c_cl = cblockp->c_info;
-		clistp->c_cc = 0;
-	} else {
-		cblockp = (struct cblock *)((intptr_t)clistp->c_cl & ~CROUND);
-		if (((intptr_t)clistp->c_cl & CROUND) == 0) {
-			struct cblock *prev = (cblockp - 1);
-
-			if (clistp->c_cbcount >= clistp->c_cbreserved) {
-				if (clistp->c_cbcount >= clistp->c_cbmax
-				    || cslushcount <= 0) {
-					splx(s);
-					return (-1);
-				}
-				--cslushcount;
-			}
-			cblockp = cblock_alloc();
-			clistp->c_cbcount++;
-			prev->c_next = cblockp;
-			clistp->c_cl = cblockp->c_info;
-		}
-	}
-
-	/*
-	 * If this character is quoted, set the quote bit, if not, clear it.
-	 */
-	if (chr & TTY_QUOTE) {
-		setbit(cblockp->c_quote, clistp->c_cl - (char *)cblockp->c_info);
-		/*
-		 * Use one of the spare quote bits to record that something
-		 * may be quoted.
-		 */
-		setbit(cblockp->c_quote, CBQSIZE * NBBY - 1);
-	} else
-		clrbit(cblockp->c_quote, clistp->c_cl - (char *)cblockp->c_info);
-
-	*clistp->c_cl++ = chr;
-	clistp->c_cc++;
-
-	splx(s);
-	return (0);
-}
-
-/*
- * Copy data from linear buffer to clist chain. Return the
- * number of characters not copied.
- */
-int
-b_to_q(src, amount, clistp)
-	char *src;
-	int amount;
-	struct clist *clistp;
-{
-	struct cblock *cblockp;
-	char *firstbyte, *lastbyte;
-	u_char startmask, endmask;
-	int startbit, endbit, num_between, numc;
-	int s;
-
-	/*
-	 * Avoid allocating an initial cblock and then not using it.
-	 * c_cc == 0 must imply c_cbount == 0.
-	 */
-	if (amount <= 0)
-		return (amount);
-
-	s = spltty();
-
-	/*
-	 * If there are no cblocks assigned to this clist yet,
-	 * then get one.
-	 */
-	if (clistp->c_cl == NULL) {
-		if (clistp->c_cbreserved < 1) {
-			splx(s);
-			printf("b_to_q to a clist with no reserved cblocks.\n");
-			return (amount);	/* nothing done */
-		}
-		cblockp = cblock_alloc();
-		clistp->c_cbcount = 1;
-		clistp->c_cf = clistp->c_cl = cblockp->c_info;
-		clistp->c_cc = 0;
-	} else {
-		cblockp = (struct cblock *)((intptr_t)clistp->c_cl & ~CROUND);
-	}
-
-	while (amount) {
-		/*
-		 * Get another cblock if needed.
-		 */
-		if (((intptr_t)clistp->c_cl & CROUND) == 0) {
-			struct cblock *prev = cblockp - 1;
-
-			if (clistp->c_cbcount >= clistp->c_cbreserved) {
-				if (clistp->c_cbcount >= clistp->c_cbmax
-				    || cslushcount <= 0) {
-					splx(s);
-					return (amount);
-				}
-				--cslushcount;
-			}
-			cblockp = cblock_alloc();
-			clistp->c_cbcount++;
-			prev->c_next = cblockp;
-			clistp->c_cl = cblockp->c_info;
-		}
-
-		/*
-		 * Copy a chunk of the linear buffer up to the end
-		 * of this cblock.
-		 */
-		numc = min(amount, (char *)(cblockp + 1) - clistp->c_cl);
-		bcopy(src, clistp->c_cl, numc);
-
-		/*
-		 * Clear quote bits if they aren't known to be clear.
-		 * The following could probably be made into a separate
-		 * "bitzero()" routine, but why bother?
-		 */
-		if (isset(cblockp->c_quote, CBQSIZE * NBBY - 1)) {
-			startbit = clistp->c_cl - (char *)cblockp->c_info;
-			endbit = startbit + numc - 1;
-
-			firstbyte = (u_char *)cblockp->c_quote + (startbit / NBBY);
-			lastbyte = (u_char *)cblockp->c_quote + (endbit / NBBY);
-
-			/*
-			 * Calculate mask of bits to preserve in first and
-			 * last bytes.
-			 */
-			startmask = NBBY - (startbit % NBBY);
-			startmask = 0xff >> startmask;
-			endmask = (endbit % NBBY);
-			endmask = 0xff << (endmask + 1);
-
-			if (firstbyte != lastbyte) {
-				*firstbyte &= startmask;
-				*lastbyte &= endmask;
-
-				num_between = lastbyte - firstbyte - 1;
-				if (num_between)
-					bzero(firstbyte + 1, num_between);
-			} else {
-				*firstbyte &= (startmask | endmask);
-			}
-		}
-
-		/*
-		 * ...and update pointer for the next chunk.
-		 */
-		src += numc;
-		clistp->c_cl += numc;
-		clistp->c_cc += numc;
-		amount -= numc;
-		/*
-		 * If we go through the loop again, it's always
-		 * for data in the next cblock, so by adding one (cblock),
-		 * (which makes the pointer 1 beyond the end of this
-		 * cblock) we prepare for the assignment of 'prev'
-		 * above.
-		 */
-		cblockp += 1;
-
-	}
-
-	splx(s);
-	return (amount);
-}
-
-/*
- * Get the next character in the clist. Store it at dst. Don't
- * advance any clist pointers, but return a pointer to the next
- * character position.
- */
-char *
-nextc(clistp, cp, dst)
-	struct clist *clistp;
-	char *cp;
-	int *dst;
-{
-	struct cblock *cblockp;
-
-	++cp;
-	/*
-	 * See if the next character is beyond the end of
-	 * the clist.
-	 */
-	if (clistp->c_cc && (cp != clistp->c_cl)) {
-		/*
-		 * If the next character is beyond the end of this
-		 * cblock, advance to the next cblock.
-		 */
-		if (((intptr_t)cp & CROUND) == 0)
-			cp = ((struct cblock *)cp - 1)->c_next->c_info;
-		cblockp = (struct cblock *)((intptr_t)cp & ~CROUND);
-
-		/*
-		 * Get the character. Set the quote flag if this character
-		 * is quoted.
-		 */
-		*dst = (u_char)*cp | (isset(cblockp->c_quote, cp - (char *)cblockp->c_info) ? TTY_QUOTE : 0);
-
-		return (cp);
-	}
-
-	return (NULL);
-}
-
-/*
- * "Unput" a character from a clist.
- */
-int
-unputc(clistp)
-	struct clist *clistp;
-{
-	struct cblock *cblockp = 0, *cbp = 0;
-	int s;
-	int chr = -1;
-
-
-	s = spltty();
-
-	if (clistp->c_cc) {
-		--clistp->c_cc;
-		--clistp->c_cl;
-
-		chr = (u_char)*clistp->c_cl;
-
-		cblockp = (struct cblock *)((intptr_t)clistp->c_cl & ~CROUND);
-
-		/*
-		 * Set quote flag if this character was quoted.
-		 */
-		if (isset(cblockp->c_quote, (u_char *)clistp->c_cl - cblockp->c_info))
-			chr |= TTY_QUOTE;
-
-		/*
-		 * If all of the characters have been unput in this
-		 * cblock, then find the previous one and free this
-		 * one.
-		 */
-		if (clistp->c_cc && (clistp->c_cl <= (char *)cblockp->c_info)) {
-			cbp = (struct cblock *)((intptr_t)clistp->c_cf & ~CROUND);
-
-			while (cbp->c_next != cblockp)
-				cbp = cbp->c_next;
-
-			/*
-			 * When the previous cblock is at the end, the 'last'
-			 * pointer always points (invalidly) one past.
-			 */
-			clistp->c_cl = (char *)(cbp+1);
-			cblock_free(cblockp);
-			if (--clistp->c_cbcount >= clistp->c_cbreserved)
-				++cslushcount;
-			cbp->c_next = NULL;
-		}
-	}
-
-	/*
-	 * If there are no more characters on the list, then
-	 * free the last cblock.
-	 */
-	if ((clistp->c_cc == 0) && clistp->c_cl) {
-		cblockp = (struct cblock *)((intptr_t)clistp->c_cl & ~CROUND);
-		cblock_free(cblockp);
-		if (--clistp->c_cbcount >= clistp->c_cbreserved)
-			++cslushcount;
-		clistp->c_cf = clistp->c_cl = NULL;
-	}
-
-	splx(s);
-	return (chr);
-}
-
-/*
- * Move characters in source clist to destination clist,
- * preserving quote bits.
- */
-void
-catq(src_clistp, dest_clistp)
-	struct clist *src_clistp, *dest_clistp;
-{
-	int chr, s;
-
-	s = spltty();
-	/*
-	 * If the destination clist is empty (has no cblocks atttached),
-	 * and there are no possible complications with the resource counters,
-	 * then we simply assign the current clist to the destination.
-	 */
-	if (!dest_clistp->c_cf
-	    && src_clistp->c_cbcount <= src_clistp->c_cbmax
-	    && src_clistp->c_cbcount <= dest_clistp->c_cbmax) {
-		dest_clistp->c_cf = src_clistp->c_cf;
-		dest_clistp->c_cl = src_clistp->c_cl;
-		src_clistp->c_cf = src_clistp->c_cl = NULL;
-
-		dest_clistp->c_cc = src_clistp->c_cc;
-		src_clistp->c_cc = 0;
-		dest_clistp->c_cbcount = src_clistp->c_cbcount;
-		src_clistp->c_cbcount = 0;
-
-		splx(s);
-		return;
-	}
-
-	splx(s);
-
-	/*
-	 * XXX  This should probably be optimized to more than one
-	 * character at a time.
-	 */
-	while ((chr = getc(src_clistp)) != -1)
-		putc(chr, dest_clistp);
-}