From 5de6a45e07a5027a8c6df5a9c354fbfd9c76aec1 Mon Sep 17 00:00:00 2001 From: ed Date: Thu, 29 May 2008 12:50:46 +0000 Subject: [PATCH] Remove the distinction between device minor and unit numbers. Even though we got rid of device major numbers some time ago, device drivers still need to provide unique device minor numbers to make_dev(). These numbers are only used inside the kernel. They are not related to device major and minor numbers which are visible in devfs. These are actually based on the inode number of the device. It would eventually be nice to remove minor numbers entirely, but we don't want to be too agressive here. Because the 8-15 bits of the device number field (si_drv0) are still reserved for the major number, there is no 1:1 mapping of the device minor and unit numbers. Because this is now unused, remove the restrictions on these numbers. The MAXMAJOR definition was actually used for two purposes. It was used to convert both the userspace and kernelspace device numbers to their major/minor pair, which is why it is now named UMINORMASK. minor2unit() and unit2minor() have now become useless. Both minor() and dev2unit() now serve the same purpose. We should eventually remove some of them, at least turning them into macro's. If devfs would become completely minor number unaware, we could consider using si_drv0 directly, just like si_drv1 and si_drv2. Approved by: philip (mentor) --- sys/dev/ieee488/upd7210.c | 2 +- sys/dev/led/led.c | 3 ++- sys/dev/md/md.c | 3 ++- sys/geom/geom_dev.c | 2 +- sys/kern/kern_conf.c | 19 ++++++++----------- sys/sys/conf.h | 2 -- 6 files changed, 14 insertions(+), 17 deletions(-) diff --git a/sys/dev/ieee488/upd7210.c b/sys/dev/ieee488/upd7210.c index c014f9fcc81e..27359e2a175c 100644 --- a/sys/dev/ieee488/upd7210.c +++ b/sys/dev/ieee488/upd7210.c @@ -277,7 +277,7 @@ upd7210attach(struct upd7210 *u) struct cdev *dev; if (units == NULL) - units = new_unrhdr(0, minor2unit(MAXMINOR), NULL); + units = new_unrhdr(0, INT_MAX, NULL); u->unit = alloc_unr(units); mtx_init(&u->mutex, "gpib", NULL, MTX_DEF); u->cdev = make_dev(&gpib_l_cdevsw, u->unit, diff --git a/sys/dev/led/led.c b/sys/dev/led/led.c index b9aae50cc162..73af18a6c758 100644 --- a/sys/dev/led/led.c +++ b/sys/dev/led/led.c @@ -15,6 +15,7 @@ __FBSDID("$FreeBSD$"); #include #include #include +#include #include #include #include @@ -298,7 +299,7 @@ static void led_drvinit(void *unused) { - led_unit = new_unrhdr(0, minor2unit(MAXMINOR), NULL); + led_unit = new_unrhdr(0, INT_MAX, NULL); mtx_init(&led_mtx, "LED mtx", NULL, MTX_DEF); sx_init(&led_sx, "LED sx"); callout_init(&led_ch, CALLOUT_MPSAFE); diff --git a/sys/dev/md/md.c b/sys/dev/md/md.c index 639f4d8b37ac..93b407da1b59 100644 --- a/sys/dev/md/md.c +++ b/sys/dev/md/md.c @@ -64,6 +64,7 @@ #include #include #include +#include #include #include #include @@ -1234,7 +1235,7 @@ g_md_init(struct g_class *mp __unused) md_preloaded(ptr, len); sx_xunlock(&md_sx); } - status_dev = make_dev(&mdctl_cdevsw, MAXMINOR, UID_ROOT, GID_WHEEL, + status_dev = make_dev(&mdctl_cdevsw, INT_MAX, UID_ROOT, GID_WHEEL, 0600, MDCTL_NAME); g_topology_lock(); } diff --git a/sys/geom/geom_dev.c b/sys/geom/geom_dev.c index c379d06e9e1c..4abbfc076904 100644 --- a/sys/geom/geom_dev.c +++ b/sys/geom/geom_dev.c @@ -88,7 +88,7 @@ static void g_dev_init(struct g_class *mp) { - unithdr = new_unrhdr(0, minor2unit(MAXMINOR), NULL); + unithdr = new_unrhdr(0, INT_MAX, NULL); } void diff --git a/sys/kern/kern_conf.c b/sys/kern/kern_conf.c index d4a421c00b52..39cc8a7171f4 100644 --- a/sys/kern/kern_conf.c +++ b/sys/kern/kern_conf.c @@ -501,7 +501,7 @@ minor(struct cdev *x) { if (x == NULL) return NODEV; - return(x->si_drv0 & MAXMINOR); + return (x->si_drv0); } int @@ -510,23 +510,21 @@ dev2unit(struct cdev *x) if (x == NULL) return NODEV; - return (minor2unit(minor(x))); + return (x->si_drv0); } u_int minor2unit(u_int _minor) { - KASSERT((_minor & ~MAXMINOR) == 0, ("Illegal minor %x", _minor)); - return ((_minor & 0xff) | ((_minor >> 8) & 0xffff00)); + return (_minor); } int unit2minor(int unit) { - KASSERT(unit <= 0xffffff, ("Invalid unit (%d) in unit2minor", unit)); - return ((unit & 0xff) | ((unit << 8) & ~0xffff)); + return (unit); } static void @@ -580,16 +578,18 @@ newdev(struct cdevsw *csw, int y, struct cdev *si) return (si); } +#define UMINORMASK 0xffff00ffU + int uminor(dev_t dev) { - return (dev & MAXMINOR); + return (dev & UMINORMASK); } int umajor(dev_t dev) { - return ((dev & ~MAXMINOR) >> 8); + return ((dev & ~UMINORMASK) >> 8); } static void @@ -697,9 +697,6 @@ make_dev_credv(int flags, struct cdevsw *devsw, int minornr, struct cdev *dev; int i; - KASSERT((minornr & ~MAXMINOR) == 0, - ("Invalid minor (0x%x) in make_dev", minornr)); - dev = devfs_alloc(); dev_lock(); prep_cdevsw(devsw); diff --git a/sys/sys/conf.h b/sys/sys/conf.h index 3b4e17440cce..b9ba8fd15146 100644 --- a/sys/sys/conf.h +++ b/sys/sys/conf.h @@ -223,8 +223,6 @@ struct cdevsw { #define NUMCDEVSW 256 -#define MAXMINOR 0xffff00ffU - struct module; struct devsw_module_data {