kern_conf.c revision 135843
155682Smarkm/*- 255682Smarkm * Copyright (c) 1999-2002 Poul-Henning Kamp 355682Smarkm * All rights reserved. 455682Smarkm * 555682Smarkm * Redistribution and use in source and binary forms, with or without 655682Smarkm * modification, are permitted provided that the following conditions 755682Smarkm * are met: 855682Smarkm * 1. Redistributions of source code must retain the above copyright 955682Smarkm * notice, this list of conditions and the following disclaimer. 1055682Smarkm * 2. Redistributions in binary form must reproduce the above copyright 1155682Smarkm * notice, this list of conditions and the following disclaimer in the 1255682Smarkm * documentation and/or other materials provided with the distribution. 1355682Smarkm * 1455682Smarkm * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 1555682Smarkm * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 1655682Smarkm * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 1755682Smarkm * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 1855682Smarkm * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 1955682Smarkm * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2055682Smarkm * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2155682Smarkm * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2255682Smarkm * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2355682Smarkm * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 2455682Smarkm * SUCH DAMAGE. 2555682Smarkm */ 2655682Smarkm 2755682Smarkm#include <sys/cdefs.h> 2855682Smarkm__FBSDID("$FreeBSD: head/sys/kern/kern_conf.c 135843 2004-09-27 06:18:25Z phk $"); 2955682Smarkm 3055682Smarkm#include <sys/param.h> 3155682Smarkm#include <sys/kernel.h> 3255682Smarkm#include <sys/systm.h> 3355682Smarkm#include <sys/bio.h> 3455682Smarkm#include <sys/lock.h> 3555682Smarkm#include <sys/mutex.h> 3655682Smarkm#include <sys/sysctl.h> 3755682Smarkm#include <sys/module.h> 3855682Smarkm#include <sys/malloc.h> 3955682Smarkm#include <sys/conf.h> 4055682Smarkm#include <sys/vnode.h> 4155682Smarkm#include <sys/queue.h> 4255682Smarkm#include <sys/poll.h> 4355682Smarkm#include <sys/ctype.h> 4455682Smarkm#include <sys/tty.h> 4555682Smarkm#include <machine/stdarg.h> 4655682Smarkm 4755682Smarkmstatic MALLOC_DEFINE(M_DEVT, "cdev", "cdev storage"); 4855682Smarkm 4955682Smarkm/* Built at compile time from sys/conf/majors */ 5055682Smarkmextern unsigned char reserved_majors[256]; 5155682Smarkm 5255682Smarkm/* 5355682Smarkm * This is the number of hash-buckets. Experiments with 'real-life' 5455682Smarkm * dev_t's show that a prime halfway between two powers of two works 5555682Smarkm * best. 5655682Smarkm */ 5755682Smarkm#define DEVT_HASH 83 5855682Smarkm 5955682Smarkm/* The number of struct cdev *'s we can create before malloc(9) kick in. */ 6055682Smarkm#define DEVT_STASH 50 6155682Smarkm 6255682Smarkmstatic struct cdev devt_stash[DEVT_STASH]; 6355682Smarkm 6455682Smarkmstatic LIST_HEAD(, cdev) dev_hash[DEVT_HASH]; 6555682Smarkm 6655682Smarkmstatic LIST_HEAD(, cdev) dev_free; 6755682Smarkm 6855682Smarkmstatic int free_devt; 6955682SmarkmSYSCTL_INT(_debug, OID_AUTO, free_devt, CTLFLAG_RW, &free_devt, 0, ""); 7055682Smarkm 7155682Smarkmstatic struct mtx devmtx; 7255682Smarkmstatic void freedev(struct cdev *dev); 7355682Smarkmstatic struct cdev *newdev(int x, int y); 7455682Smarkm 7555682Smarkm 7655682Smarkmvoid 7755682Smarkmdev_lock(void) 7855682Smarkm{ 7955682Smarkm if (!mtx_initialized(&devmtx)) 8055682Smarkm mtx_init(&devmtx, "cdev", NULL, MTX_DEF); 8155682Smarkm mtx_lock(&devmtx); 8255682Smarkm} 8355682Smarkm 8455682Smarkmvoid 8555682Smarkmdev_unlock(void) 8655682Smarkm{ 8755682Smarkm 8855682Smarkm mtx_unlock(&devmtx); 8955682Smarkm} 9055682Smarkm 9155682Smarkmvoid 9255682Smarkmdev_ref(struct cdev *dev) 9355682Smarkm{ 9455682Smarkm 9555682Smarkm dev_lock(); 9655682Smarkm dev->si_refcount++; 9755682Smarkm dev_unlock(); 9855682Smarkm} 9955682Smarkm 10055682Smarkmvoid 10155682Smarkmdev_rel(struct cdev *dev) 10255682Smarkm{ 10355682Smarkm 10455682Smarkm dev->si_refcount--; 10555682Smarkm KASSERT(dev->si_refcount >= 0, 10655682Smarkm ("dev_rel(%s) gave negative count", devtoname(dev))); 10755682Smarkm if (dev->si_devsw == NULL && dev->si_refcount == 0) { 10855682Smarkm LIST_REMOVE(dev, si_list); 10955682Smarkm freedev(dev); 11055682Smarkm } 11155682Smarkm} 11255682Smarkmstruct cdevsw * 11355682Smarkmdev_refthread(struct cdev *dev) 11455682Smarkm{ 11555682Smarkm struct cdevsw *csw; 11655682Smarkm 11755682Smarkm mtx_assert(&devmtx, MA_NOTOWNED); 11855682Smarkm dev_lock(); 11955682Smarkm csw = dev->si_devsw; 12055682Smarkm if (csw != NULL) 12155682Smarkm dev->si_threadcount++; 12255682Smarkm dev_unlock(); 12355682Smarkm return (csw); 12455682Smarkm} 12555682Smarkm 12655682Smarkmvoid 12755682Smarkmdev_relthread(struct cdev *dev) 12855682Smarkm{ 12955682Smarkm 13055682Smarkm mtx_assert(&devmtx, MA_NOTOWNED); 13155682Smarkm dev_lock(); 13255682Smarkm dev->si_threadcount--; 13355682Smarkm dev_unlock(); 13455682Smarkm} 13555682Smarkm 13655682Smarkmint 13755682Smarkmnullop(void) 13855682Smarkm{ 13955682Smarkm 14055682Smarkm return (0); 14155682Smarkm} 14255682Smarkm 14355682Smarkmint 14455682Smarkmeopnotsupp(void) 14555682Smarkm{ 14655682Smarkm 14755682Smarkm return (EOPNOTSUPP); 14855682Smarkm} 14955682Smarkm 15055682Smarkmstatic int 15155682Smarkmenxio(void) 15255682Smarkm{ 15355682Smarkm return (ENXIO); 15455682Smarkm} 15555682Smarkm 15655682Smarkmstatic int 15755682Smarkmenodev(void) 15855682Smarkm{ 15955682Smarkm return (ENODEV); 16055682Smarkm} 16155682Smarkm 16255682Smarkm/* Define a dead_cdevsw for use when devices leave unexpectedly. */ 16355682Smarkm 16455682Smarkm#define dead_open (d_open_t *)enxio 16555682Smarkm#define dead_close (d_close_t *)enxio 16655682Smarkm#define dead_read (d_read_t *)enxio 16755682Smarkm#define dead_write (d_write_t *)enxio 16855682Smarkm#define dead_ioctl (d_ioctl_t *)enxio 16955682Smarkm#define dead_poll (d_poll_t *)enodev 17055682Smarkm#define dead_mmap (d_mmap_t *)enodev 17155682Smarkm 17255682Smarkmstatic void 17355682Smarkmdead_strategy(struct bio *bp) 17455682Smarkm{ 17555682Smarkm 17655682Smarkm biofinish(bp, NULL, ENXIO); 17755682Smarkm} 17855682Smarkm 17955682Smarkm#define dead_dump (dumper_t *)enxio 18055682Smarkm#define dead_kqfilter (d_kqfilter_t *)enxio 18155682Smarkm 18255682Smarkmstatic struct cdevsw dead_cdevsw = { 18355682Smarkm .d_version = D_VERSION, 18455682Smarkm .d_flags = D_NEEDGIANT, /* XXX: does dead_strategy need this ? */ 18555682Smarkm .d_open = dead_open, 18655682Smarkm .d_close = dead_close, 18755682Smarkm .d_read = dead_read, 18855682Smarkm .d_write = dead_write, 18955682Smarkm .d_ioctl = dead_ioctl, 19055682Smarkm .d_poll = dead_poll, 19155682Smarkm .d_mmap = dead_mmap, 19255682Smarkm .d_strategy = dead_strategy, 19355682Smarkm .d_name = "dead", 19455682Smarkm .d_maj = 255, 19555682Smarkm .d_dump = dead_dump, 19655682Smarkm .d_kqfilter = dead_kqfilter 19755682Smarkm}; 19855682Smarkm 19955682Smarkm/* Default methods if driver does not specify method */ 20055682Smarkm 20155682Smarkm#define null_open (d_open_t *)nullop 20255682Smarkm#define null_close (d_close_t *)nullop 20355682Smarkm#define no_read (d_read_t *)enodev 20455682Smarkm#define no_write (d_write_t *)enodev 20555682Smarkm#define no_ioctl (d_ioctl_t *)enodev 20655682Smarkm#define no_mmap (d_mmap_t *)enodev 20755682Smarkm#define no_kqfilter (d_kqfilter_t *)enodev 20855682Smarkm 20955682Smarkmstatic void 21055682Smarkmno_strategy(struct bio *bp) 21155682Smarkm{ 21255682Smarkm 21355682Smarkm biofinish(bp, NULL, ENODEV); 21455682Smarkm} 21555682Smarkm 21655682Smarkmstatic int 21755682Smarkmno_poll(struct cdev *dev __unused, int events, struct thread *td __unused) 21855682Smarkm{ 21955682Smarkm /* 22055682Smarkm * Return true for read/write. If the user asked for something 22155682Smarkm * special, return POLLNVAL, so that clients have a way of 22255682Smarkm * determining reliably whether or not the extended 22355682Smarkm * functionality is present without hard-coding knowledge 22455682Smarkm * of specific filesystem implementations. 22555682Smarkm * Stay in sync with vop_nopoll(). 22655682Smarkm */ 22755682Smarkm if (events & ~POLLSTANDARD) 22855682Smarkm return (POLLNVAL); 22955682Smarkm 23055682Smarkm return (events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM)); 23155682Smarkm} 23255682Smarkm 23355682Smarkm#define no_dump (dumper_t *)enodev 23455682Smarkm 23555682Smarkm/* 23655682Smarkm * struct cdev * and u_dev_t primitives 23755682Smarkm */ 23855682Smarkm 23955682Smarkmint 24055682Smarkmmajor(struct cdev *x) 24155682Smarkm{ 24255682Smarkm if (x == NULL) 24355682Smarkm return NODEV; 24455682Smarkm return((x->si_udev >> 8) & 0xff); 24555682Smarkm} 24655682Smarkm 24755682Smarkmint 24855682Smarkmminor(struct cdev *x) 24955682Smarkm{ 25055682Smarkm if (x == NULL) 25155682Smarkm return NODEV; 25255682Smarkm return(x->si_udev & 0xffff00ff); 25355682Smarkm} 25455682Smarkm 25555682Smarkmint 25655682Smarkmdev2unit(struct cdev *x) 25755682Smarkm{ 25855682Smarkm int i; 25955682Smarkm 26055682Smarkm if (x == NULL) 26155682Smarkm return NODEV; 26255682Smarkm i = minor(x); 26355682Smarkm return ((i & 0xff) | (i >> 8)); 26455682Smarkm} 26555682Smarkm 26655682Smarkmint 26755682Smarkmunit2minor(int unit) 26855682Smarkm{ 26955682Smarkm 27055682Smarkm KASSERT(unit <= 0xffffff, ("Invalid unit (%d) in unit2minor", unit)); 27155682Smarkm return ((unit & 0xff) | ((unit << 8) & ~0xffff)); 27255682Smarkm} 27355682Smarkm 27455682Smarkmstatic struct cdev * 27555682Smarkmallocdev(void) 27655682Smarkm{ 27755682Smarkm static int stashed; 27855682Smarkm struct cdev *si; 27955682Smarkm 28055682Smarkm if (LIST_FIRST(&dev_free)) { 28155682Smarkm si = LIST_FIRST(&dev_free); 28255682Smarkm LIST_REMOVE(si, si_hash); 28355682Smarkm } else if (stashed >= DEVT_STASH) { 28455682Smarkm MALLOC(si, struct cdev *, sizeof(*si), M_DEVT, 28555682Smarkm M_USE_RESERVE | M_ZERO | M_WAITOK); 28655682Smarkm } else { 28755682Smarkm si = devt_stash + stashed++; 28855682Smarkm bzero(si, sizeof *si); 28955682Smarkm si->si_flags |= SI_STASHED; 29055682Smarkm } 29155682Smarkm si->__si_namebuf[0] = '\0'; 29255682Smarkm si->si_name = si->__si_namebuf; 29355682Smarkm LIST_INIT(&si->si_children); 29455682Smarkm return (si); 29555682Smarkm} 29655682Smarkm 29755682Smarkmstatic struct cdev * 29855682Smarkmnewdev(int x, int y) 29955682Smarkm{ 30055682Smarkm struct cdev *si; 30155682Smarkm dev_t udev; 30255682Smarkm int hash; 30355682Smarkm 30455682Smarkm if (x == umajor(NODEV) && y == uminor(NODEV)) 30555682Smarkm panic("newdev of NODEV"); 30655682Smarkm udev = (x << 8) | y; 30755682Smarkm hash = udev % DEVT_HASH; 30855682Smarkm LIST_FOREACH(si, &dev_hash[hash], si_hash) { 30955682Smarkm if (si->si_udev == udev) 31055682Smarkm return (si); 31155682Smarkm } 31255682Smarkm si = allocdev(); 31355682Smarkm si->si_udev = udev; 31455682Smarkm LIST_INSERT_HEAD(&dev_hash[hash], si, si_hash); 31555682Smarkm return (si); 31655682Smarkm} 31755682Smarkm 31855682Smarkmstatic void 31955682Smarkmfreedev(struct cdev *dev) 32055682Smarkm{ 32155682Smarkm 32255682Smarkm if (dev->si_flags & SI_STASHED) { 32355682Smarkm bzero(dev, sizeof(*dev)); 32455682Smarkm dev->si_flags |= SI_STASHED; 32555682Smarkm LIST_INSERT_HEAD(&dev_free, dev, si_hash); 32655682Smarkm } else { 32755682Smarkm FREE(dev, M_DEVT); 32855682Smarkm } 32955682Smarkm} 33055682Smarkm 33155682Smarkmdev_t 33255682Smarkmdev2udev(struct cdev *x) 33355682Smarkm{ 33455682Smarkm if (x == NULL) 33555682Smarkm return (NODEV); 33655682Smarkm return (x->si_udev); 33755682Smarkm} 33855682Smarkm 33955682Smarkmstruct cdev * 34055682Smarkmfindcdev(dev_t udev) 34155682Smarkm{ 34255682Smarkm struct cdev *si; 34355682Smarkm int hash; 34455682Smarkm 34555682Smarkm if (udev == NODEV) 34655682Smarkm return (NULL); 34755682Smarkm hash = udev % DEVT_HASH; 34855682Smarkm LIST_FOREACH(si, &dev_hash[hash], si_hash) { 34955682Smarkm if (si->si_udev == udev) 35055682Smarkm return (si); 35155682Smarkm } 35255682Smarkm return (NULL); 35355682Smarkm} 35455682Smarkm 35555682Smarkmint 35655682Smarkmuminor(dev_t dev) 35755682Smarkm{ 35855682Smarkm return (dev & 0xffff00ff); 35955682Smarkm} 36055682Smarkm 36155682Smarkmint 36255682Smarkmumajor(dev_t dev) 36355682Smarkm{ 36455682Smarkm return ((dev & 0xff00) >> 8); 36555682Smarkm} 36655682Smarkm 36755682Smarkmstatic void 36855682Smarkmfind_major(struct cdevsw *devsw) 36955682Smarkm{ 37055682Smarkm int i; 37155682Smarkm 37255682Smarkm for (i = NUMCDEVSW - 1; i > 0; i--) 37355682Smarkm if (reserved_majors[i] != i) 37455682Smarkm break; 37555682Smarkm KASSERT(i > 0, ("Out of major numbers (%s)", devsw->d_name)); 37655682Smarkm devsw->d_maj = i; 37755682Smarkm reserved_majors[i] = i; 37855682Smarkm devsw->d_flags |= D_ALLOCMAJ; 37955682Smarkm} 38055682Smarkm 38155682Smarkmstatic void 38255682Smarkmfini_cdevsw(struct cdevsw *devsw) 38355682Smarkm{ 38455682Smarkm if (devsw->d_flags & D_ALLOCMAJ) { 38555682Smarkm reserved_majors[devsw->d_maj] = 0; 38655682Smarkm devsw->d_maj = MAJOR_AUTO; 38755682Smarkm devsw->d_flags &= ~D_ALLOCMAJ; 38855682Smarkm } else if (devsw->d_maj == 0) 38955682Smarkm devsw->d_maj = 256; 39055682Smarkm devsw->d_flags &= ~D_INIT; 39155682Smarkm} 39255682Smarkm 39355682Smarkmstatic void 39455682Smarkmprep_cdevsw(struct cdevsw *devsw) 39555682Smarkm{ 39655682Smarkm 39755682Smarkm dev_lock(); 39855682Smarkm 39955682Smarkm if (devsw->d_version != D_VERSION_00) { 40055682Smarkm printf( 40155682Smarkm "WARNING: Device driver \"%s\" has wrong version %s\n", 40255682Smarkm devsw->d_name, "and is disabled. Recompile KLD module."); 40355682Smarkm devsw->d_open = dead_open; 40455682Smarkm devsw->d_close = dead_close; 40555682Smarkm devsw->d_read = dead_read; 40655682Smarkm devsw->d_write = dead_write; 40755682Smarkm devsw->d_ioctl = dead_ioctl; 40855682Smarkm devsw->d_poll = dead_poll; 40955682Smarkm devsw->d_mmap = dead_mmap; 41055682Smarkm devsw->d_strategy = dead_strategy; 41155682Smarkm devsw->d_dump = dead_dump; 41255682Smarkm devsw->d_kqfilter = dead_kqfilter; 41355682Smarkm } 41455682Smarkm 41555682Smarkm if (devsw->d_flags & D_TTY) { 41655682Smarkm if (devsw->d_ioctl == NULL) devsw->d_ioctl = ttyioctl; 41755682Smarkm if (devsw->d_read == NULL) devsw->d_read = ttyread; 41855682Smarkm if (devsw->d_write == NULL) devsw->d_write = ttywrite; 41955682Smarkm if (devsw->d_kqfilter == NULL) devsw->d_kqfilter = ttykqfilter; 42055682Smarkm if (devsw->d_poll == NULL) devsw->d_poll = ttypoll; 42155682Smarkm } 42255682Smarkm 42355682Smarkm if (devsw->d_open == NULL) devsw->d_open = null_open; 42455682Smarkm if (devsw->d_close == NULL) devsw->d_close = null_close; 42555682Smarkm if (devsw->d_read == NULL) devsw->d_read = no_read; 42655682Smarkm if (devsw->d_write == NULL) devsw->d_write = no_write; 42755682Smarkm if (devsw->d_ioctl == NULL) devsw->d_ioctl = no_ioctl; 42855682Smarkm if (devsw->d_poll == NULL) devsw->d_poll = no_poll; 42955682Smarkm if (devsw->d_mmap == NULL) devsw->d_mmap = no_mmap; 43055682Smarkm if (devsw->d_strategy == NULL) devsw->d_strategy = no_strategy; 43155682Smarkm if (devsw->d_dump == NULL) devsw->d_dump = no_dump; 43255682Smarkm if (devsw->d_kqfilter == NULL) devsw->d_kqfilter = no_kqfilter; 43355682Smarkm 43455682Smarkm LIST_INIT(&devsw->d_devs); 43555682Smarkm 43655682Smarkm devsw->d_flags |= D_INIT; 43755682Smarkm 43855682Smarkm if (devsw->d_maj == MAJOR_AUTO) { 43955682Smarkm find_major(devsw); 44055682Smarkm } else { 44155682Smarkm if (devsw->d_maj == 256) /* XXX: tty_cons.c is magic */ 44255682Smarkm devsw->d_maj = 0; 44355682Smarkm KASSERT(devsw->d_maj >= 0 && devsw->d_maj < 256, 44455682Smarkm ("Invalid major (%d) in make_dev", devsw->d_maj)); 44555682Smarkm if (reserved_majors[devsw->d_maj] != devsw->d_maj) { 44655682Smarkm printf("WARNING: driver \"%s\" used %s %d\n", 44755682Smarkm devsw->d_name, "unreserved major device number", 44855682Smarkm devsw->d_maj); 44955682Smarkm reserved_majors[devsw->d_maj] = devsw->d_maj; 45055682Smarkm } 45155682Smarkm } 45255682Smarkm dev_unlock(); 45355682Smarkm} 45455682Smarkm 45555682Smarkmstruct cdev * 45655682Smarkmmake_dev(struct cdevsw *devsw, int minornr, uid_t uid, gid_t gid, int perms, const char *fmt, ...) 45755682Smarkm{ 45855682Smarkm struct cdev *dev; 45955682Smarkm va_list ap; 46055682Smarkm int i; 46155682Smarkm 46255682Smarkm KASSERT((minornr & ~0xffff00ff) == 0, 46355682Smarkm ("Invalid minor (0x%x) in make_dev", minornr)); 46455682Smarkm 46555682Smarkm if (!(devsw->d_flags & D_INIT)) 46655682Smarkm prep_cdevsw(devsw); 46755682Smarkm dev = newdev(devsw->d_maj, minornr); 46855682Smarkm if (dev->si_flags & SI_CHEAPCLONE && 46955682Smarkm dev->si_flags & SI_NAMED && 47055682Smarkm dev->si_devsw == devsw) { 47155682Smarkm /* 47255682Smarkm * This is allowed as it removes races and generally 47355682Smarkm * simplifies cloning devices. 47455682Smarkm * XXX: still ?? 47555682Smarkm */ 47655682Smarkm return (dev); 47755682Smarkm } 47855682Smarkm dev_lock(); 47955682Smarkm KASSERT(!(dev->si_flags & SI_NAMED), 48055682Smarkm ("make_dev() by driver %s on pre-existing device (maj=%d, min=%d, name=%s)", 48155682Smarkm devsw->d_name, major(dev), minor(dev), devtoname(dev))); 48255682Smarkm 48355682Smarkm va_start(ap, fmt); 48455682Smarkm i = vsnrprintf(dev->__si_namebuf, sizeof dev->__si_namebuf, 32, fmt, ap); 48555682Smarkm if (i > (sizeof dev->__si_namebuf - 1)) { 48655682Smarkm printf("WARNING: Device name truncated! (%s)\n", 48755682Smarkm dev->__si_namebuf); 48855682Smarkm } 48955682Smarkm va_end(ap); 49055682Smarkm dev->si_devsw = devsw; 49155682Smarkm dev->si_uid = uid; 49255682Smarkm dev->si_gid = gid; 49355682Smarkm dev->si_mode = perms; 49455682Smarkm dev->si_flags |= SI_NAMED; 49555682Smarkm 49655682Smarkm LIST_INSERT_HEAD(&devsw->d_devs, dev, si_list); 49755682Smarkm devfs_create(dev); 49855682Smarkm dev_unlock(); 49955682Smarkm return (dev); 50055682Smarkm} 50155682Smarkm 50255682Smarkmint 50355682Smarkmdev_named(struct cdev *pdev, const char *name) 50455682Smarkm{ 50555682Smarkm struct cdev *cdev; 50655682Smarkm 50755682Smarkm if (strcmp(devtoname(pdev), name) == 0) 50855682Smarkm return (1); 50955682Smarkm LIST_FOREACH(cdev, &pdev->si_children, si_siblings) 51055682Smarkm if (strcmp(devtoname(cdev), name) == 0) 51155682Smarkm return (1); 51255682Smarkm return (0); 51355682Smarkm} 51455682Smarkm 51555682Smarkmvoid 51655682Smarkmdev_depends(struct cdev *pdev, struct cdev *cdev) 51755682Smarkm{ 51855682Smarkm 51955682Smarkm dev_lock(); 52055682Smarkm cdev->si_parent = pdev; 52155682Smarkm cdev->si_flags |= SI_CHILD; 52255682Smarkm LIST_INSERT_HEAD(&pdev->si_children, cdev, si_siblings); 52355682Smarkm dev_unlock(); 52455682Smarkm} 52555682Smarkm 52655682Smarkmstruct cdev * 52755682Smarkmmake_dev_alias(struct cdev *pdev, const char *fmt, ...) 52855682Smarkm{ 52955682Smarkm struct cdev *dev; 53055682Smarkm va_list ap; 53155682Smarkm int i; 53255682Smarkm 53355682Smarkm dev = allocdev(); 53455682Smarkm dev_lock(); 53555682Smarkm dev->si_flags |= SI_ALIAS; 53655682Smarkm dev->si_flags |= SI_NAMED; 53755682Smarkm va_start(ap, fmt); 53855682Smarkm i = vsnrprintf(dev->__si_namebuf, sizeof dev->__si_namebuf, 32, fmt, ap); 53955682Smarkm if (i > (sizeof dev->__si_namebuf - 1)) { 54055682Smarkm printf("WARNING: Device name truncated! (%s)\n", 54155682Smarkm dev->__si_namebuf); 54255682Smarkm } 54355682Smarkm va_end(ap); 54455682Smarkm 54555682Smarkm devfs_create(dev); 54655682Smarkm dev_unlock(); 54755682Smarkm dev_depends(pdev, dev); 54855682Smarkm return (dev); 54955682Smarkm} 55055682Smarkm 55155682Smarkmstatic void 55255682Smarkmidestroy_dev(struct cdev *dev) 55355682Smarkm{ 55455682Smarkm struct cdevsw *csw; 55555682Smarkm 55655682Smarkm KASSERT(dev->si_flags & SI_NAMED, 55755682Smarkm ("WARNING: Driver mistake: destroy_dev on %d/%d\n", 55855682Smarkm major(dev), minor(dev))); 55955682Smarkm 56055682Smarkm devfs_destroy(dev); 56155682Smarkm 56255682Smarkm /* Remove name marking */ 56355682Smarkm dev->si_flags &= ~SI_NAMED; 56455682Smarkm 56555682Smarkm /* If we are a child, remove us from the parents list */ 56655682Smarkm if (dev->si_flags & SI_CHILD) { 56755682Smarkm LIST_REMOVE(dev, si_siblings); 56855682Smarkm dev->si_flags &= ~SI_CHILD; 56955682Smarkm } 57055682Smarkm 57155682Smarkm /* Kill our children */ 57255682Smarkm while (!LIST_EMPTY(&dev->si_children)) 57355682Smarkm idestroy_dev(LIST_FIRST(&dev->si_children)); 57455682Smarkm 57555682Smarkm /* Remove from clone list */ 57655682Smarkm if (dev->si_flags & SI_CLONELIST) { 57755682Smarkm LIST_REMOVE(dev, si_clone); 57855682Smarkm dev->si_flags &= ~SI_CLONELIST; 57955682Smarkm } 58055682Smarkm 58155682Smarkm csw = dev->si_devsw; 58255682Smarkm dev->si_devsw = NULL; 58355682Smarkm while (csw->d_purge != NULL && dev->si_threadcount) { 58455682Smarkm printf("Purging %lu threads from %s\n", 58555682Smarkm dev->si_threadcount, devtoname(dev)); 58655682Smarkm csw->d_purge(dev); 58755682Smarkm msleep(csw, &devmtx, PRIBIO, "devprg", hz/10); 58855682Smarkm } 58955682Smarkm 59055682Smarkm dev->si_drv1 = 0; 59155682Smarkm dev->si_drv2 = 0; 59255682Smarkm bzero(&dev->__si_u, sizeof(dev->__si_u)); 59355682Smarkm 59455682Smarkm if (!(dev->si_flags & SI_ALIAS)) { 59555682Smarkm /* Remove from cdevsw list */ 59655682Smarkm LIST_REMOVE(dev, si_list); 59755682Smarkm 59855682Smarkm /* If cdevsw has no struct cdev *'s, clean it */ 59955682Smarkm if (LIST_EMPTY(&dev->si_devsw->d_devs)) 60055682Smarkm fini_cdevsw(dev->si_devsw); 60155682Smarkm 60255682Smarkm LIST_REMOVE(dev, si_hash); 60355682Smarkm } 60455682Smarkm dev->si_flags &= ~SI_ALIAS; 60555682Smarkm 60655682Smarkm if (dev->si_refcount > 0) { 60755682Smarkm LIST_INSERT_HEAD(&dead_cdevsw.d_devs, dev, si_list); 60855682Smarkm } else { 60955682Smarkm freedev(dev); 61055682Smarkm } 61155682Smarkm} 61255682Smarkm 61355682Smarkmvoid 61455682Smarkmdestroy_dev(struct cdev *dev) 61555682Smarkm{ 61655682Smarkm 61755682Smarkm dev_lock(); 61855682Smarkm idestroy_dev(dev); 61955682Smarkm dev_unlock(); 62055682Smarkm} 62155682Smarkm 62255682Smarkmconst char * 62355682Smarkmdevtoname(struct cdev *dev) 62455682Smarkm{ 62555682Smarkm char *p; 62655682Smarkm struct cdevsw *csw; 62755682Smarkm int mynor; 62855682Smarkm 62955682Smarkm if (dev->si_name[0] == '#' || dev->si_name[0] == '\0') { 63055682Smarkm p = dev->si_name; 63155682Smarkm sprintf(p, "#%d", major(dev)); 63255682Smarkm p += strlen(p); 63355682Smarkm csw = dev_refthread(dev); 63455682Smarkm if (csw != NULL) { 63555682Smarkm sprintf(p, "(%s)", csw->d_name); 63655682Smarkm dev_relthread(dev); 63755682Smarkm } 63855682Smarkm p += strlen(p); 63955682Smarkm mynor = minor(dev); 64055682Smarkm if (mynor < 0 || mynor > 255) 64155682Smarkm sprintf(p, "/%#x", (u_int)mynor); 64255682Smarkm else 64355682Smarkm sprintf(p, "/%d", mynor); 64455682Smarkm } 64555682Smarkm return (dev->si_name); 64655682Smarkm} 64755682Smarkm 64855682Smarkmint 64955682Smarkmdev_stdclone(char *name, char **namep, const char *stem, int *unit) 65055682Smarkm{ 65155682Smarkm int u, i; 65255682Smarkm 65355682Smarkm i = strlen(stem); 65455682Smarkm if (bcmp(stem, name, i) != 0) 65555682Smarkm return (0); 65655682Smarkm if (!isdigit(name[i])) 65755682Smarkm return (0); 65855682Smarkm u = 0; 65955682Smarkm if (name[i] == '0' && isdigit(name[i+1])) 66055682Smarkm return (0); 66155682Smarkm while (isdigit(name[i])) { 66255682Smarkm u *= 10; 66355682Smarkm u += name[i++] - '0'; 66455682Smarkm } 66555682Smarkm if (u > 0xffffff) 66655682Smarkm return (0); 66755682Smarkm *unit = u; 66855682Smarkm if (namep) 66955682Smarkm *namep = &name[i]; 67055682Smarkm if (name[i]) 67155682Smarkm return (2); 67255682Smarkm return (1); 67355682Smarkm} 67455682Smarkm 67555682Smarkm/* 67655682Smarkm * Helper functions for cloning device drivers. 67755682Smarkm * 67855682Smarkm * The objective here is to make it unnecessary for the device drivers to 67955682Smarkm * use rman or similar to manage their unit number space. Due to the way 68055682Smarkm * we do "on-demand" devices, using rman or other "private" methods 68155682Smarkm * will be very tricky to lock down properly once we lock down this file. 68255682Smarkm * 68355682Smarkm * Instead we give the drivers these routines which puts the struct cdev *'s 68455682Smarkm * that are to be managed on their own list, and gives the driver the ability 68555682Smarkm * to ask for the first free unit number or a given specified unit number. 68655682Smarkm * 68755682Smarkm * In addition these routines support paired devices (pty, nmdm and similar) 68855682Smarkm * by respecting a number of "flag" bits in the minor number. 68955682Smarkm * 69055682Smarkm */ 69155682Smarkm 69255682Smarkmstruct clonedevs { 69355682Smarkm LIST_HEAD(,cdev) head; 69455682Smarkm}; 69555682Smarkm 69655682Smarkmvoid 69755682Smarkmclone_setup(struct clonedevs **cdp) 69855682Smarkm{ 69955682Smarkm 70055682Smarkm *cdp = malloc(sizeof **cdp, M_DEVBUF, M_WAITOK | M_ZERO); 70155682Smarkm LIST_INIT(&(*cdp)->head); 70255682Smarkm} 703 704int 705clone_create(struct clonedevs **cdp, struct cdevsw *csw, int *up, struct cdev **dp, u_int extra) 706{ 707 struct clonedevs *cd; 708 struct cdev *dev, *dl, *de; 709 int unit, low, u; 710 711 KASSERT(*cdp != NULL, 712 ("clone_setup() not called in driver \"%s\"", csw->d_name)); 713 KASSERT(!(extra & CLONE_UNITMASK), 714 ("Illegal extra bits (0x%x) in clone_create", extra)); 715 KASSERT(*up <= CLONE_UNITMASK, 716 ("Too high unit (0x%x) in clone_create", *up)); 717 718 if (csw->d_maj == MAJOR_AUTO) 719 find_major(csw); 720 721 /* 722 * Search the list for a lot of things in one go: 723 * A preexisting match is returned immediately. 724 * The lowest free unit number if we are passed -1, and the place 725 * in the list where we should insert that new element. 726 * The place to insert a specified unit number, if applicable 727 * the end of the list. 728 */ 729 unit = *up; 730 low = extra; 731 de = dl = NULL; 732 cd = *cdp; 733 LIST_FOREACH(dev, &cd->head, si_clone) { 734 u = dev2unit(dev); 735 if (u == (unit | extra)) { 736 *dp = dev; 737 return (0); 738 } 739 if (unit == -1 && u == low) { 740 low++; 741 de = dev; 742 continue; 743 } 744 if (u > (unit | extra)) { 745 dl = dev; 746 break; 747 } 748 de = dev; 749 } 750 if (unit == -1) 751 unit = low & CLONE_UNITMASK; 752 dev = newdev(csw->d_maj, unit2minor(unit | extra)); 753 KASSERT(!(dev->si_flags & SI_CLONELIST), 754 ("Dev %p should not be on clonelist", dev)); 755 if (dl != NULL) 756 LIST_INSERT_BEFORE(dl, dev, si_clone); 757 else if (de != NULL) 758 LIST_INSERT_AFTER(de, dev, si_clone); 759 else 760 LIST_INSERT_HEAD(&cd->head, dev, si_clone); 761 dev->si_flags |= SI_CLONELIST; 762 *up = unit; 763 return (1); 764} 765 766/* 767 * Kill everything still on the list. The driver should already have 768 * disposed of any softc hung of the struct cdev *'s at this time. 769 */ 770void 771clone_cleanup(struct clonedevs **cdp) 772{ 773 struct cdev *dev, *tdev; 774 struct clonedevs *cd; 775 776 cd = *cdp; 777 if (cd == NULL) 778 return; 779 LIST_FOREACH_SAFE(dev, &cd->head, si_clone, tdev) { 780 KASSERT(dev->si_flags & SI_NAMED, 781 ("Driver has goofed in cloning underways udev %x", dev->si_udev)); 782 destroy_dev(dev); 783 } 784 free(cd, M_DEVBUF); 785 *cdp = NULL; 786} 787 788/* 789 * Helper sysctl for devname(3). We're given a struct cdev * and return 790 * the name, if any, registered by the device driver. 791 */ 792static int 793sysctl_devname(SYSCTL_HANDLER_ARGS) 794{ 795 int error; 796 dev_t ud; 797 struct cdev *dev; 798 799 error = SYSCTL_IN(req, &ud, sizeof (ud)); 800 if (error) 801 return (error); 802 if (ud == NODEV) 803 return(EINVAL); 804 dev = findcdev(ud); 805 if (dev == NULL) 806 error = ENOENT; 807 else 808 error = SYSCTL_OUT(req, dev->si_name, strlen(dev->si_name) + 1); 809 return (error); 810} 811 812SYSCTL_PROC(_kern, OID_AUTO, devname, CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_ANYBODY, 813 NULL, 0, sysctl_devname, "", "devname(3) handler"); 814