xref: /xnu-8796.101.5/bsd/dev/i386/conf.c (revision aca3beaa3dfbd42498b42c5e5ce20a938e6554e5)

/*
 * Copyright (c) 1997-2020 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
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * 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,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * 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@
 */
/*
 * Copyright (c) 1993 NeXT Computer, Inc.
 *
 * UNIX Device switch tables.
 *
 * HISTORY
 *
 * 30 July 1997 Umesh Vaishampayan ([email protected])
 *      enabled file descriptor pseudo-device.
 * 18 June 1993 ? at NeXT
 *	Cleaned up a lot of stuff in this file.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/ioctl.h>
#include <sys/tty.h>
#include <sys/conf.h>

/* Prototypes that should be elsewhere: */
extern dev_t    chrtoblk(dev_t dev);
extern int      chrtoblk_set(int cdev, int bdev);

struct bdevsw   bdevsw[] =
{
	/*
	 *	For block devices, every other block of 8 slots is
	 *	reserved for Apple.  The other slots are available for
	 *	the user.  This way we can both add new entries without
	 *	running into each other.  Be sure to fill in Apple's
	 *	8 reserved slots when you jump over us -- we'll do the
	 *	same for you.
	 */

	/* 0 - 7 are reserved for Apple */

	NO_BDEVICE,                                                     /* 0*/
	NO_BDEVICE,                                                     /* 1*/
	NO_BDEVICE,                                                     /* 2*/
	NO_BDEVICE,                                                     /* 3*/
	NO_BDEVICE,                                                     /* 4*/
	NO_BDEVICE,                                                     /* 5*/
	NO_BDEVICE,                                                     /* 6*/
	NO_BDEVICE,                                                     /* 7*/

	/* 8 - 15 are reserved to the user */
	NO_BDEVICE,                                                     /* 8*/
	NO_BDEVICE,                                                     /* 9*/
	NO_BDEVICE,                                                     /*10*/
	NO_BDEVICE,                                                     /*11*/
	NO_BDEVICE,                                                     /*12*/
	NO_BDEVICE,                                                     /*13*/
	NO_BDEVICE,                                                     /*14*/
	NO_BDEVICE,                                                     /*15*/

	/* 16 - 23 are reserved for Apple */
	NO_BDEVICE,                                                     /*16*/
	NO_BDEVICE,                                                     /*17*/
	NO_BDEVICE,                                                     /*18*/
	NO_BDEVICE,                                                     /*18*/
	NO_BDEVICE,                                                     /*20*/
	NO_BDEVICE,                                                     /*21*/
	NO_BDEVICE,                                                     /*22*/
	NO_BDEVICE,                                                     /*23*/
};

const int nblkdev = sizeof(bdevsw) / sizeof(bdevsw[0]);

extern struct tty *km_tty[];
extern d_open_t         cnopen;
extern d_close_t        cnclose;
extern d_read_t         cnread;
extern d_write_t        cnwrite;
extern d_ioctl_t        cnioctl;
extern d_select_t       cnselect;
extern d_open_t         kmopen;
extern d_close_t        kmclose;
extern d_read_t         kmread;
extern d_write_t        kmwrite;
extern d_ioctl_t        kmioctl;
extern d_open_t         sgopen;
extern d_close_t        sgclose;
extern d_ioctl_t        sgioctl;

#if NVOL > 0
extern d_open_t         volopen;
extern d_close_t        volclose;
extern d_ioctl_t        volioctl;
#else
#define volopen         eno_opcl
#define volclose        eno_opcl
#define volioctl        eno_ioctl
#endif

extern d_open_t         cttyopen;
extern d_read_t         cttyread;
extern d_write_t        cttywrite;
extern d_ioctl_t        cttyioctl;
extern d_select_t       cttyselect;

extern d_read_t         mmread;
extern d_write_t        mmwrite;
extern d_ioctl_t        mmioctl;
#define mmselect        (select_fcn_t *)(void (*)(void))seltrue
#define mmmmap          eno_mmap

#include <pty.h>
#if NPTY > 0
extern d_open_t         ptsopen;
extern d_close_t        ptsclose;
extern d_read_t         ptsread;
extern d_write_t        ptswrite;
extern d_stop_t         ptsstop;
extern d_select_t       ptsselect;
extern d_open_t         ptcopen;
extern d_close_t        ptcclose;
extern d_read_t         ptcread;
extern d_write_t        ptcwrite;
extern d_select_t       ptcselect;
extern d_ioctl_t        ptyioctl;
#else
#define ptsopen         eno_opcl
#define ptsclose        eno_opcl
#define ptsread         eno_rdwrt
#define ptswrite        eno_rdwrt
#define ptsstop         nulldev

#define ptcopen         eno_opcl
#define ptcclose        eno_opcl
#define ptcread         eno_rdwrt
#define ptcwrite        eno_rdwrt
#define ptcselect       eno_select
#define ptyioctl        eno_ioctl
#endif

extern d_open_t         logopen;
extern d_close_t        logclose;
extern d_read_t         logread;
extern d_ioctl_t        logioctl;
extern d_select_t       logselect;

extern d_open_t         oslog_streamopen;
extern d_close_t        oslog_streamclose;
extern d_read_t         oslog_streamread;
extern d_ioctl_t        oslog_streamioctl;
extern d_select_t       oslog_streamselect;

extern d_open_t         oslogopen;
extern d_close_t        oslogclose;
extern d_select_t       oslogselect;
extern d_ioctl_t        oslogioctl;

#define nulldevfp        (void (*)(void))&nulldev

#define nullopen        (d_open_t *)nulldevfp
#define nullclose       (d_close_t *)nulldevfp
#define nullread        (d_read_t *)nulldevfp
#define nullwrite       (d_write_t *)nulldevfp
#define nullioctl       (d_ioctl_t *)nulldevfp
#define nullselect      (d_select_t *)nulldevfp
#define nullstop        (d_stop_t *)nulldevfp
#define nullreset       (d_reset_t *)nulldevfp

struct cdevsw cdevsw[] = {
	/*
	 * To add character devices to this table dynamically, use cdevsw_add.
	 */

	[0] = {
		cnopen, cnclose, cnread, cnwrite,
		cnioctl, nullstop, nullreset, 0, cnselect,
		eno_mmap, eno_strat, eno_getc, eno_putc, D_TTY
	},
	[1] = NO_CDEVICE,
	[2] = {
		cttyopen, nullclose, cttyread, cttywrite,
		cttyioctl, nullstop, nullreset, 0, cttyselect,
		eno_mmap, eno_strat, eno_getc, eno_putc, D_TTY
	},
	[3] = {
		nullopen, nullclose, mmread, mmwrite,
		mmioctl, nullstop, nullreset, 0, mmselect,
		mmmmap, eno_strat, eno_getc, eno_putc, D_DISK
	},
	[PTC_MAJOR] = {
		ptsopen, ptsclose, ptsread, ptswrite,
		ptyioctl, ptsstop, nullreset, 0, ptsselect,
		eno_mmap, eno_strat, eno_getc, eno_putc, D_TTY
	},
	[PTS_MAJOR] = {
		ptcopen, ptcclose, ptcread, ptcwrite,
		ptyioctl, nullstop, nullreset, 0, ptcselect,
		eno_mmap, eno_strat, eno_getc, eno_putc, D_TTY
	},
	[6] = {
		logopen, logclose, logread, eno_rdwrt,
		logioctl, eno_stop, nullreset, 0, logselect,
		eno_mmap, eno_strat, eno_getc, eno_putc, 0
	},
	[7] = {
		oslogopen, oslogclose, eno_rdwrt, eno_rdwrt,
		oslogioctl, eno_stop, nullreset, 0, oslogselect,
		eno_mmap, eno_strat, eno_getc, eno_putc, 0
	},
	[8] = {
		oslog_streamopen, oslog_streamclose, oslog_streamread, eno_rdwrt,
		oslog_streamioctl, eno_stop, nullreset, 0, oslog_streamselect,
		eno_mmap, eno_strat, eno_getc, eno_putc, 0
	},
	[9 ... 11] = NO_CDEVICE,
	[12] = {
		kmopen, kmclose, kmread, kmwrite,
		kmioctl, nullstop, nullreset, km_tty, ttselect,
		eno_mmap, eno_strat, eno_getc, eno_putc, 0
	},
	[13 ... 63] = NO_CDEVICE,
};
const int nchrdev = sizeof(cdevsw) / sizeof(cdevsw[0]);

uint64_t cdevsw_flags[sizeof(cdevsw) / sizeof(cdevsw[0])];

#include        <sys/vnode.h> /* for VCHR and VBLK */
/*
 * return true if a disk
 */
int
isdisk(dev_t dev, int type)
{
	dev_t   maj = major(dev);

	switch (type) {
	case VCHR:
		maj = chrtoblk(dev);
		if (maj == NODEV) {
			break;
		}
		OS_FALLTHROUGH;
	case VBLK:
		if (bdevsw[maj].d_type == D_DISK) {
			return 1;
		}
		break;
	}
	return 0;
}

static int chrtoblktab[] = {[0 ... nchrdev] = NODEV };

/*
 * convert chr dev to blk dev
 */
dev_t
chrtoblk(dev_t dev)
{
	int blkmaj;

	if (major(dev) >= nchrdev) {
		return NODEV;
	}
	blkmaj = chrtoblktab[major(dev)];
	if (blkmaj == NODEV) {
		return NODEV;
	}
	return makedev(blkmaj, minor(dev));
}

int
chrtoblk_set(int cdev, int bdev)
{
	if (cdev >= nchrdev) {
		return -1;
	}
	if (bdev != NODEV && bdev >= nblkdev) {
		return -1;
	}
	chrtoblktab[cdev] = bdev;
	return 0;
}