kern_conf.c revision 126080
111126Sjulian/*- 2103722Sphk * Copyright (c) 1999-2002 Poul-Henning Kamp 311126Sjulian * All rights reserved. 411126Sjulian * 511126Sjulian * Redistribution and use in source and binary forms, with or without 611126Sjulian * modification, are permitted provided that the following conditions 711126Sjulian * are met: 811126Sjulian * 1. Redistributions of source code must retain the above copyright 911126Sjulian * notice, this list of conditions and the following disclaimer. 1011126Sjulian * 2. Redistributions in binary form must reproduce the above copyright 1111126Sjulian * notice, this list of conditions and the following disclaimer in the 1211126Sjulian * documentation and/or other materials provided with the distribution. 1311126Sjulian * 14103722Sphk * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15103722Sphk * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 1611126Sjulian * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17103722Sphk * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 1811126Sjulian * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 1911126Sjulian * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2011126Sjulian * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2111126Sjulian * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2211126Sjulian * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2311126Sjulian * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 2411126Sjulian * SUCH DAMAGE. 2511126Sjulian */ 2611126Sjulian 27116182Sobrien#include <sys/cdefs.h> 28116182Sobrien__FBSDID("$FreeBSD: head/sys/kern/kern_conf.c 126080 2004-02-21 21:10:55Z phk $"); 29116182Sobrien 3011126Sjulian#include <sys/param.h> 3148936Sphk#include <sys/kernel.h> 3283366Sjulian#include <sys/systm.h> 33111179Sphk#include <sys/bio.h> 3490737Sgreen#include <sys/lock.h> 3590737Sgreen#include <sys/mutex.h> 3650549Sphk#include <sys/sysctl.h> 3736735Sdfr#include <sys/module.h> 3848936Sphk#include <sys/malloc.h> 3911126Sjulian#include <sys/conf.h> 4012954Sjulian#include <sys/vnode.h> 4148936Sphk#include <sys/queue.h> 42120514Sphk#include <sys/poll.h> 4365374Sphk#include <sys/ctype.h> 44126078Sphk#include <sys/tty.h> 4549535Sphk#include <machine/stdarg.h> 4611126Sjulian 4769774Sphkstatic MALLOC_DEFINE(M_DEVT, "dev_t", "dev_t storage"); 4848936Sphk 49111622Sphk/* Built at compile time from sys/conf/majors */ 50111622Sphkextern unsigned char reserved_majors[256]; 51111622Sphk 5250522Sphk/* 5350522Sphk * This is the number of hash-buckets. Experiements with 'real-life' 5450522Sphk * udev_t's show that a prime halfway between two powers of two works 5550522Sphk * best. 5650522Sphk */ 5748936Sphk#define DEVT_HASH 83 5850522Sphk 5950522Sphk/* The number of dev_t's we can create before malloc(9) kick in. */ 6048936Sphk#define DEVT_STASH 50 6148936Sphk 62104043Sphkstatic struct cdev devt_stash[DEVT_STASH]; 6348936Sphk 64104043Sphkstatic LIST_HEAD(, cdev) dev_hash[DEVT_HASH]; 6548936Sphk 66104043Sphkstatic LIST_HEAD(, cdev) dev_free; 6750549Sphk 6850549Sphkstatic int free_devt; 6950549SphkSYSCTL_INT(_debug, OID_AUTO, free_devt, CTLFLAG_RW, &free_devt, 0, ""); 7050549Sphk 71120514Sphkint 72120514Sphknullop(void) 73120514Sphk{ 7485603Sphk 75120514Sphk return (0); 76120514Sphk} 77120514Sphk 78120514Sphkint 79120514Sphkeopnotsupp(void) 80120514Sphk{ 81120514Sphk 82120514Sphk return (EOPNOTSUPP); 83120514Sphk} 84120514Sphk 85111179Sphkstatic int 86111179Sphkenxio(void) 87111179Sphk{ 88111179Sphk return (ENXIO); 89111179Sphk} 90111179Sphk 91120514Sphkstatic int 92120514Sphkenodev(void) 93120514Sphk{ 94120514Sphk return (ENODEV); 95120514Sphk} 96120514Sphk 97120514Sphk/* Define a dead_cdevsw for use when devices leave unexpectedly. */ 98120514Sphk 99111179Sphk#define dead_open (d_open_t *)enxio 100111179Sphk#define dead_close (d_close_t *)enxio 101111179Sphk#define dead_read (d_read_t *)enxio 102111179Sphk#define dead_write (d_write_t *)enxio 103111179Sphk#define dead_ioctl (d_ioctl_t *)enxio 104120514Sphk#define dead_poll (d_poll_t *)enodev 105120514Sphk#define dead_mmap (d_mmap_t *)enodev 106111179Sphk 107111179Sphkstatic void 108111179Sphkdead_strategy(struct bio *bp) 109111179Sphk{ 110111179Sphk 111111179Sphk biofinish(bp, NULL, ENXIO); 112111179Sphk} 113111179Sphk 114111220Sphk#define dead_dump (dumper_t *)enxio 115111179Sphk#define dead_kqfilter (d_kqfilter_t *)enxio 116111179Sphk 117111179Sphkstatic struct cdevsw dead_cdevsw = { 118126080Sphk .d_version = D_VERSION, 119126080Sphk .d_flags = D_NEEDGIANT, /* XXX: does dead_strategy need this ? */ 120111815Sphk .d_open = dead_open, 121111815Sphk .d_close = dead_close, 122111815Sphk .d_read = dead_read, 123111815Sphk .d_write = dead_write, 124111815Sphk .d_ioctl = dead_ioctl, 125111815Sphk .d_poll = dead_poll, 126111815Sphk .d_mmap = dead_mmap, 127111815Sphk .d_strategy = dead_strategy, 128111815Sphk .d_name = "dead", 129111815Sphk .d_maj = 255, 130111815Sphk .d_dump = dead_dump, 131111815Sphk .d_kqfilter = dead_kqfilter 132111179Sphk}; 133111179Sphk 134120514Sphk/* Default methods if driver does not specify method */ 135111179Sphk 136120514Sphk#define null_open (d_open_t *)nullop 137120514Sphk#define null_close (d_close_t *)nullop 138120514Sphk#define no_read (d_read_t *)enodev 139120514Sphk#define no_write (d_write_t *)enodev 140120514Sphk#define no_ioctl (d_ioctl_t *)enodev 141120514Sphk#define no_mmap (d_mmap_t *)enodev 142120514Sphk 143120514Sphkstatic int 144120514Sphkno_kqfilter(dev_t dev __unused, struct knote *kn __unused) 145120514Sphk{ 146120514Sphk 147120514Sphk return (1); 148120514Sphk} 149120514Sphk 150120514Sphkstatic void 151120514Sphkno_strategy(struct bio *bp) 152120514Sphk{ 153120514Sphk 154120514Sphk biofinish(bp, NULL, ENODEV); 155120514Sphk} 156120514Sphk 157120514Sphkstatic int 158120514Sphkno_poll(dev_t dev __unused, int events, struct thread *td __unused) 159120514Sphk{ 160120514Sphk /* 161120514Sphk * Return true for read/write. If the user asked for something 162120514Sphk * special, return POLLNVAL, so that clients have a way of 163120514Sphk * determining reliably whether or not the extended 164120514Sphk * functionality is present without hard-coding knowledge 165120514Sphk * of specific filesystem implementations. 166120514Sphk * Stay in sync with vop_nopoll(). 167120514Sphk */ 168120514Sphk if (events & ~POLLSTANDARD) 169120514Sphk return (POLLNVAL); 170120514Sphk 171120514Sphk return (events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM)); 172120514Sphk} 173120514Sphk 174120514Sphk#define no_dump (dumper_t *)enodev 175120514Sphk 17647640Sphkstruct cdevsw * 17747640Sphkdevsw(dev_t dev) 17851927Sphk{ 17949679Sphk if (dev->si_devsw) 18049679Sphk return (dev->si_devsw); 181111179Sphk return (&dead_cdevsw); 18247640Sphk} 18347640Sphk 18447640Sphk/* 18547028Sphk * dev_t and u_dev_t primitives 18647028Sphk */ 18747028Sphk 18851927Sphkint 18947028Sphkmajor(dev_t x) 19047028Sphk{ 19148936Sphk if (x == NODEV) 19248936Sphk return NOUDEV; 19348936Sphk return((x->si_udev >> 8) & 0xff); 19447028Sphk} 19547028Sphk 19647028Sphkint 19747028Sphkminor(dev_t x) 19847028Sphk{ 19948936Sphk if (x == NODEV) 20048936Sphk return NOUDEV; 20148936Sphk return(x->si_udev & 0xffff00ff); 20247028Sphk} 20347028Sphk 20449826Sphkint 20566067Sphkdev2unit(dev_t x) 20649826Sphk{ 20749826Sphk int i; 20849826Sphk 20949826Sphk if (x == NODEV) 21049826Sphk return NOUDEV; 21149826Sphk i = minor(x); 21249826Sphk return ((i & 0xff) | (i >> 8)); 21349826Sphk} 21449826Sphk 21566067Sphkint 21666067Sphkunit2minor(int unit) 21766067Sphk{ 21866067Sphk 21974522Sphk KASSERT(unit <= 0xffffff, ("Invalid unit (%d) in unit2minor", unit)); 22066067Sphk return ((unit & 0xff) | ((unit << 8) & ~0xffff)); 22166067Sphk} 22266067Sphk 22364880Sphkstatic dev_t 22464880Sphkallocdev(void) 22564880Sphk{ 22664880Sphk static int stashed; 227104043Sphk struct cdev *si; 22864880Sphk 229103101Sphk if (LIST_FIRST(&dev_free)) { 230103101Sphk si = LIST_FIRST(&dev_free); 231103101Sphk LIST_REMOVE(si, si_hash); 232103101Sphk } else if (stashed >= DEVT_STASH) { 233104043Sphk MALLOC(si, struct cdev *, sizeof(*si), M_DEVT, 234111146Sphk M_USE_RESERVE | M_ZERO | M_WAITOK); 23564880Sphk } else { 23664880Sphk si = devt_stash + stashed++; 23777215Sphk bzero(si, sizeof *si); 238103101Sphk si->si_flags |= SI_STASHED; 23964880Sphk } 240110317Sphk si->__si_namebuf[0] = '\0'; 241110317Sphk si->si_name = si->__si_namebuf; 24277215Sphk LIST_INIT(&si->si_children); 24373942Smckusick TAILQ_INIT(&si->si_snapshots); 24464880Sphk return (si); 24564880Sphk} 24664880Sphk 24747680Sphkdev_t 24847028Sphkmakedev(int x, int y) 24947028Sphk{ 250104043Sphk struct cdev *si; 25148936Sphk udev_t udev; 25248936Sphk int hash; 25348936Sphk 25455414Sphk if (x == umajor(NOUDEV) && y == uminor(NOUDEV)) 25571342Sphk panic("makedev of NOUDEV"); 25648936Sphk udev = (x << 8) | y; 25748936Sphk hash = udev % DEVT_HASH; 25850549Sphk LIST_FOREACH(si, &dev_hash[hash], si_hash) { 25948936Sphk if (si->si_udev == udev) 26048936Sphk return (si); 26148936Sphk } 26264880Sphk si = allocdev(); 26348936Sphk si->si_udev = udev; 26450549Sphk LIST_INSERT_HEAD(&dev_hash[hash], si, si_hash); 265125850Sbde return (si); 26647028Sphk} 26747028Sphk 26850549Sphkvoid 26950549Sphkfreedev(dev_t dev) 27050549Sphk{ 27150549Sphk 27250549Sphk if (!free_devt) 27350549Sphk return; 27450549Sphk if (SLIST_FIRST(&dev->si_hlist)) 27550549Sphk return; 27651927Sphk if (dev->si_devsw || dev->si_drv1 || dev->si_drv2) 27750549Sphk return; 27850549Sphk LIST_REMOVE(dev, si_hash); 27950549Sphk if (dev->si_flags & SI_STASHED) { 28050549Sphk bzero(dev, sizeof(*dev)); 28177215Sphk dev->si_flags |= SI_STASHED; 28250549Sphk LIST_INSERT_HEAD(&dev_free, dev, si_hash); 28350549Sphk } else { 28450549Sphk FREE(dev, M_DEVT); 28550549Sphk } 28650549Sphk} 28750549Sphk 28847028Sphkudev_t 28947028Sphkdev2udev(dev_t x) 29047028Sphk{ 29148936Sphk if (x == NODEV) 292125850Sbde return (NOUDEV); 29348936Sphk return (x->si_udev); 29447028Sphk} 29547028Sphk 29647028Sphkdev_t 29747028Sphkudev2dev(udev_t x, int b) 29847028Sphk{ 29955414Sphk 30055414Sphk if (x == NOUDEV) 30155414Sphk return (NODEV); 30248864Sphk switch (b) { 303125850Sbde case 0: 304125850Sbde return (makedev(umajor(x), uminor(x))); 305125850Sbde default: 306125850Sbde Debugger("udev2dev(...,X)"); 307125850Sbde return (NODEV); 30848864Sphk } 30947028Sphk} 31047028Sphk 31147028Sphkint 31247028Sphkuminor(udev_t dev) 31347028Sphk{ 314125850Sbde return (dev & 0xffff00ff); 31547028Sphk} 31647028Sphk 31747028Sphkint 31847028Sphkumajor(udev_t dev) 31947028Sphk{ 320125850Sbde return ((dev & 0xff00) >> 8); 32147028Sphk} 32247028Sphk 32347028Sphkudev_t 32448859Sphkmakeudev(int x, int y) 32547028Sphk{ 326125850Sbde return ((x << 8) | y); 32747028Sphk} 32847028Sphk 329125846Sphkstatic void 330126077Sphkfind_major(struct cdevsw *devsw) 33149535Sphk{ 33249535Sphk int i; 33349535Sphk 334126077Sphk for (i = NUMCDEVSW - 1; i > 0; i--) 335126077Sphk if (reserved_majors[i] != i) 336126077Sphk break; 337126077Sphk KASSERT(i > 0, ("Out of major numbers (%s)", devsw->d_name)); 338126077Sphk devsw->d_maj = i; 339126077Sphk reserved_majors[i] = i; 340126077Sphk} 341126077Sphk 342126077Sphkstatic void 343126077Sphkprep_cdevsw(struct cdevsw *devsw) 344126077Sphk{ 345126077Sphk 346126078Sphk if (devsw->d_flags & D_TTY) { 347126078Sphk if (devsw->d_read == NULL) devsw->d_read = ttyread; 348126078Sphk if (devsw->d_write == NULL) devsw->d_write = ttywrite; 349126078Sphk if (devsw->d_kqfilter == NULL) devsw->d_kqfilter = ttykqfilter; 350126078Sphk if (devsw->d_poll == NULL) devsw->d_poll = ttypoll; 351126078Sphk } 352126078Sphk 353120514Sphk if (devsw->d_open == NULL) devsw->d_open = null_open; 354120514Sphk if (devsw->d_close == NULL) devsw->d_close = null_close; 355120514Sphk if (devsw->d_read == NULL) devsw->d_read = no_read; 356120514Sphk if (devsw->d_write == NULL) devsw->d_write = no_write; 357120514Sphk if (devsw->d_ioctl == NULL) devsw->d_ioctl = no_ioctl; 358120514Sphk if (devsw->d_poll == NULL) devsw->d_poll = no_poll; 359120514Sphk if (devsw->d_mmap == NULL) devsw->d_mmap = no_mmap; 360120514Sphk if (devsw->d_strategy == NULL) devsw->d_strategy = no_strategy; 361120514Sphk if (devsw->d_dump == NULL) devsw->d_dump = no_dump; 362120514Sphk if (devsw->d_kqfilter == NULL) devsw->d_kqfilter = no_kqfilter; 363111622Sphk if (devsw->d_maj == MAJOR_AUTO) { 364126077Sphk find_major(devsw); 365111626Sphk } else { 366112035Sphk if (devsw->d_maj == 256) /* XXX: tty_cons.c is magic */ 367112035Sphk devsw->d_maj = 0; 368111626Sphk KASSERT(devsw->d_maj >= 0 && devsw->d_maj < 256, 369111626Sphk ("Invalid major (%d) in make_dev", devsw->d_maj)); 370111626Sphk if (reserved_majors[devsw->d_maj] != devsw->d_maj) { 371111626Sphk printf("WARNING: driver \"%s\" used %s %d\n", 372111626Sphk devsw->d_name, "unreserved major device number", 373111626Sphk devsw->d_maj); 374111626Sphk reserved_majors[devsw->d_maj] = devsw->d_maj; 375111626Sphk } 376111622Sphk } 377125846Sphk} 378111622Sphk 379125846Sphkdev_t 380125850Sbdemake_dev(struct cdevsw *devsw, int minor, uid_t uid, gid_t gid, int perms, 381125850Sbde const char *fmt, ...) 382125846Sphk{ 383125850Sbde dev_t dev; 384125846Sphk va_list ap; 385125846Sphk int i; 386125846Sphk 387125846Sphk KASSERT((minor & ~0xffff00ff) == 0, 388125846Sphk ("Invalid minor (0x%x) in make_dev", minor)); 389125846Sphk prep_cdevsw(devsw); 39049535Sphk dev = makedev(devsw->d_maj, minor); 391120529Sphk if (dev->si_flags & SI_CHEAPCLONE && 392120529Sphk dev->si_flags & SI_NAMED && 393120529Sphk dev->si_devsw == devsw) { 394120529Sphk /* 395120529Sphk * This is allowed as it removes races and generally 396120529Sphk * simplifies cloning devices. 397120529Sphk */ 398120529Sphk return (dev); 399120529Sphk } 40065747Sphk if (dev->si_flags & SI_NAMED) { 40165747Sphk printf( "WARNING: Driver mistake: repeat make_dev(\"%s\")\n", 40265747Sphk dev->si_name); 40385603Sphk panic("don't do that"); 40465747Sphk } 40549535Sphk va_start(ap, fmt); 406110318Sphk i = vsnrprintf(dev->__si_namebuf, sizeof dev->__si_namebuf, 32, fmt, ap); 407110318Sphk if (i > (sizeof dev->__si_namebuf - 1)) { 408110318Sphk printf("WARNING: Device name truncated! (%s)", 409110318Sphk dev->__si_namebuf); 410110318Sphk } 41149535Sphk va_end(ap); 41249535Sphk dev->si_devsw = devsw; 41364880Sphk dev->si_uid = uid; 41464880Sphk dev->si_gid = gid; 41564880Sphk dev->si_mode = perms; 41665747Sphk dev->si_flags |= SI_NAMED; 41750092Sjulian 418111730Sphk devfs_create(dev); 41949535Sphk return (dev); 42049535Sphk} 42149535Sphk 42285076Sjlemonint 42385076Sjlemondev_named(dev_t pdev, const char *name) 42485076Sjlemon{ 42585076Sjlemon dev_t cdev; 42685076Sjlemon 42785076Sjlemon if (strcmp(devtoname(pdev), name) == 0) 42885076Sjlemon return (1); 42985076Sjlemon LIST_FOREACH(cdev, &pdev->si_children, si_siblings) 43085076Sjlemon if (strcmp(devtoname(cdev), name) == 0) 43185076Sjlemon return (1); 43285076Sjlemon return (0); 43385076Sjlemon} 43485076Sjlemon 43577215Sphkvoid 43677215Sphkdev_depends(dev_t pdev, dev_t cdev) 43777215Sphk{ 43877215Sphk 43977215Sphk cdev->si_parent = pdev; 44077215Sphk cdev->si_flags |= SI_CHILD; 44177215Sphk LIST_INSERT_HEAD(&pdev->si_children, cdev, si_siblings); 44277215Sphk} 44377215Sphk 44464880Sphkdev_t 44581068Simpmake_dev_alias(dev_t pdev, const char *fmt, ...) 44664880Sphk{ 44764880Sphk dev_t dev; 44864880Sphk va_list ap; 44964880Sphk int i; 45064880Sphk 45164880Sphk dev = allocdev(); 45264880Sphk dev->si_flags |= SI_ALIAS; 45365747Sphk dev->si_flags |= SI_NAMED; 45477215Sphk dev_depends(pdev, dev); 45564880Sphk va_start(ap, fmt); 456110318Sphk i = vsnrprintf(dev->__si_namebuf, sizeof dev->__si_namebuf, 32, fmt, ap); 457110318Sphk if (i > (sizeof dev->__si_namebuf - 1)) { 458110318Sphk printf("WARNING: Device name truncated! (%s)", 459110318Sphk dev->__si_namebuf); 460110318Sphk } 46164880Sphk va_end(ap); 46264880Sphk 463111730Sphk devfs_create(dev); 46464880Sphk return (dev); 46564880Sphk} 46664880Sphk 46750549Sphkvoid 46853000Sphkdestroy_dev(dev_t dev) 46950549Sphk{ 47065747Sphk 47165747Sphk if (!(dev->si_flags & SI_NAMED)) { 47265747Sphk printf( "WARNING: Driver mistake: destroy_dev on %d/%d\n", 47365747Sphk major(dev), minor(dev)); 47485603Sphk panic("don't do that"); 47565747Sphk } 47665747Sphk 477111730Sphk devfs_destroy(dev); 478126077Sphk dev->si_flags &= ~SI_NAMED; 479126077Sphk 48077215Sphk if (dev->si_flags & SI_CHILD) { 48177215Sphk LIST_REMOVE(dev, si_siblings); 48277215Sphk dev->si_flags &= ~SI_CHILD; 48377215Sphk } 48477215Sphk while (!LIST_EMPTY(&dev->si_children)) 48577215Sphk destroy_dev(LIST_FIRST(&dev->si_children)); 486126077Sphk if (dev->si_flags & SI_CLONELIST) { 487126077Sphk LIST_REMOVE(dev, si_clone); 488126077Sphk dev->si_flags &= ~SI_CLONELIST; 489126077Sphk } 49050549Sphk dev->si_drv1 = 0; 49150549Sphk dev->si_drv2 = 0; 49250549Sphk dev->si_devsw = 0; 49395446Sbde bzero(&dev->__si_u, sizeof(dev->__si_u)); 49465747Sphk dev->si_flags &= ~SI_ALIAS; 49550549Sphk freedev(dev); 49650549Sphk} 49750549Sphk 49851225Sbdeconst char * 49949982Sbillfdevtoname(dev_t dev) 50049982Sbillf{ 50150549Sphk char *p; 50251225Sbde int mynor; 50349982Sbillf 50450549Sphk if (dev->si_name[0] == '#' || dev->si_name[0] == '\0') { 50550549Sphk p = dev->si_name; 50650549Sphk if (devsw(dev)) 50750549Sphk sprintf(p, "#%s/", devsw(dev)->d_name); 50850549Sphk else 50950549Sphk sprintf(p, "#%d/", major(dev)); 51050549Sphk p += strlen(p); 51151225Sbde mynor = minor(dev); 51251225Sbde if (mynor < 0 || mynor > 255) 51351225Sbde sprintf(p, "%#x", (u_int)mynor); 51451225Sbde else 51551225Sbde sprintf(p, "%d", mynor); 51650549Sphk } 51749982Sbillf return (dev->si_name); 51849982Sbillf} 51965374Sphk 52065374Sphkint 52191998Sphkdev_stdclone(char *name, char **namep, const char *stem, int *unit) 52265374Sphk{ 52365374Sphk int u, i; 52465374Sphk 52575519Sbrian i = strlen(stem); 52675519Sbrian if (bcmp(stem, name, i) != 0) 52765374Sphk return (0); 52865374Sphk if (!isdigit(name[i])) 52965374Sphk return (0); 53065374Sphk u = 0; 53186461Sphk if (name[i] == '0' && isdigit(name[i+1])) 53286461Sphk return (0); 53365374Sphk while (isdigit(name[i])) { 53465374Sphk u *= 10; 53565374Sphk u += name[i++] - '0'; 53665374Sphk } 537104523Sgreen if (u > 0xffffff) 538104523Sgreen return (0); 53965374Sphk *unit = u; 54065374Sphk if (namep) 54165374Sphk *namep = &name[i]; 54265374Sphk if (name[i]) 54365374Sphk return (2); 54465374Sphk return (1); 54565374Sphk} 54665632Sphk 54765632Sphk/* 548126077Sphk * Helper functions for cloning device drivers. 549126077Sphk * 550126077Sphk * The objective here is to make it unnecessary for the device drivers to 551126077Sphk * use rman or similar to manage their unit number space. Due to the way 552126077Sphk * we do "on-demand" devices, using rman or other "private" methods 553126077Sphk * will be very tricky to lock down properly once we lock down this file. 554126077Sphk * 555126077Sphk * Instead we give the drivers these routines which puts the dev_t's that 556126077Sphk * are to be managed on their own list, and gives the driver the ability 557126077Sphk * to ask for the first free unit number or a given specified unit number. 558126077Sphk * 559126077Sphk * In addition these routines support paired devices (pty, nmdm and similar) 560126077Sphk * by respecting a number of "flag" bits in the minor number. 561126077Sphk * 562126077Sphk */ 563126077Sphk 564126077Sphkstruct clonedevs { 565126077Sphk LIST_HEAD(,cdev) head; 566126077Sphk}; 567126077Sphk 568126077Sphkint 569126077Sphkclone_create(struct clonedevs **cdp, struct cdevsw *csw, int *up, dev_t *dp, u_int extra) 570126077Sphk{ 571126077Sphk struct clonedevs *cd; 572126077Sphk dev_t dev, dl, de; 573126077Sphk int unit, low, u; 574126077Sphk 575126077Sphk KASSERT(!(extra & CLONE_UNITMASK), 576126077Sphk ("Illegal extra bits (0x%x) in clone_create", extra)); 577126077Sphk KASSERT(*up <= CLONE_UNITMASK, 578126077Sphk ("Too high unit (0x%x) in clone_create", *up)); 579126077Sphk 580126077Sphk if (csw->d_maj == MAJOR_AUTO) 581126077Sphk find_major(csw); 582126077Sphk /* if clonedevs have not been initialized, we do it here */ 583126077Sphk cd = *cdp; 584126077Sphk if (cd == NULL) { 585126077Sphk cd = malloc(sizeof *cd, M_DEVBUF, M_WAITOK | M_ZERO); 586126077Sphk LIST_INIT(&cd->head); 587126077Sphk *cdp = cd; 588126077Sphk } 589126077Sphk 590126077Sphk /* 591126077Sphk * Search the list for a lot of things in one go: 592126077Sphk * A preexisting match is returned immediately. 593126077Sphk * The lowest free unit number if we are passed -1, and the place 594126077Sphk * in the list where we should insert that new element. 595126077Sphk * The place to insert a specified unit number, if applicable 596126077Sphk * the end of the list. 597126077Sphk */ 598126077Sphk unit = *up; 599126077Sphk low = 0; 600126077Sphk de = dl = NULL; 601126077Sphk LIST_FOREACH(dev, &cd->head, si_clone) { 602126077Sphk u = dev2unit(dev); 603126077Sphk if (u == (unit | extra)) { 604126077Sphk *dp = dev; 605126077Sphk return (0); 606126077Sphk } 607126077Sphk if (unit == -1 && u == low) { 608126077Sphk low++; 609126077Sphk de = dev; 610126077Sphk continue; 611126077Sphk } 612126077Sphk if (u > unit) { 613126077Sphk dl = dev; 614126077Sphk break; 615126077Sphk } 616126077Sphk de = dev; 617126077Sphk } 618126077Sphk if (unit == -1) 619126077Sphk unit = low; 620126077Sphk dev = makedev(csw->d_maj, unit2minor(unit | extra)); 621126077Sphk KASSERT(!(dev->si_flags & SI_CLONELIST), 622126077Sphk ("Dev %p should not be on clonelist", dev)); 623126077Sphk if (dl != NULL) 624126077Sphk LIST_INSERT_BEFORE(dl, dev, si_clone); 625126077Sphk else if (de != NULL) 626126077Sphk LIST_INSERT_AFTER(de, dev, si_clone); 627126077Sphk else 628126077Sphk LIST_INSERT_HEAD(&cd->head, dev, si_clone); 629126077Sphk dev->si_flags |= SI_CLONELIST; 630126077Sphk *up = unit; 631126077Sphk return (1); 632126077Sphk} 633126077Sphk 634126077Sphk/* 635126077Sphk * Kill everything still on the list. The driver should already have 636126077Sphk * disposed of any softc hung of the dev_t's at this time. 637126077Sphk */ 638126077Sphkvoid 639126077Sphkclone_cleanup(struct clonedevs **cdp) 640126077Sphk{ 641126077Sphk dev_t dev, tdev; 642126077Sphk struct clonedevs *cd; 643126077Sphk 644126077Sphk cd = *cdp; 645126077Sphk if (cd == NULL) 646126077Sphk return; 647126077Sphk LIST_FOREACH_SAFE(dev, &cd->head, si_clone, tdev) { 648126077Sphk KASSERT(dev->si_flags & SI_NAMED, 649126077Sphk ("Driver has goofed in cloning underways udev %x", dev->si_udev)); 650126077Sphk destroy_dev(dev); 651126077Sphk } 652126077Sphk free(cd, M_DEVBUF); 653126077Sphk *cdp = NULL; 654126077Sphk} 655126077Sphk 656126077Sphk/* 65765632Sphk * Helper sysctl for devname(3). We're given a {u}dev_t and return 65865632Sphk * the name, if any, registered by the device driver. 65965632Sphk */ 66065632Sphkstatic int 66165632Sphksysctl_devname(SYSCTL_HANDLER_ARGS) 66265632Sphk{ 66365632Sphk int error; 66465632Sphk udev_t ud; 66565632Sphk dev_t dev; 66665632Sphk 66765632Sphk error = SYSCTL_IN(req, &ud, sizeof (ud)); 66865632Sphk if (error) 66965632Sphk return (error); 67071342Sphk if (ud == NOUDEV) 67171342Sphk return(EINVAL); 67265632Sphk dev = makedev(umajor(ud), uminor(ud)); 67365632Sphk if (dev->si_name[0] == '\0') 67465632Sphk error = ENOENT; 67565632Sphk else 67665632Sphk error = SYSCTL_OUT(req, dev->si_name, strlen(dev->si_name) + 1); 67765632Sphk freedev(dev); 67865632Sphk return (error); 67965632Sphk} 68065632Sphk 68167905SphkSYSCTL_PROC(_kern, OID_AUTO, devname, CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_ANYBODY, 68265632Sphk NULL, 0, sysctl_devname, "", "devname(3) handler"); 683