/* * w1_family.c * * Copyright (c) 2004 Evgeniy Polyakov * * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include #include #include /* schedule_timeout() */ #include #include #include "w1_family.h" #include "w1.h" DEFINE_SPINLOCK(w1_flock); static LIST_HEAD(w1_families); /** * w1_register_family() - register a device family driver * @newf: family to register */ int w1_register_family(struct w1_family *newf) { struct list_head *ent, *n; struct w1_family *f; int ret = 0; spin_lock(&w1_flock); list_for_each_safe(ent, n, &w1_families) { f = list_entry(ent, struct w1_family, family_entry); if (f->fid == newf->fid) { ret = -EEXIST; break; } } if (!ret) { atomic_set(&newf->refcnt, 0); list_add_tail(&newf->family_entry, &w1_families); } spin_unlock(&w1_flock); /* check default devices against the new set of drivers */ w1_reconnect_slaves(newf, 1); return ret; } /** * w1_unregister_family() - unregister a device family driver * @fent: family to unregister */ void w1_unregister_family(struct w1_family *fent) { struct list_head *ent, *n; struct w1_family *f; spin_lock(&w1_flock); list_for_each_safe(ent, n, &w1_families) { f = list_entry(ent, struct w1_family, family_entry); if (f->fid == fent->fid) { list_del(&fent->family_entry); break; } } spin_unlock(&w1_flock); /* deatch devices using this family code */ w1_reconnect_slaves(fent, 0); while (atomic_read(&fent->refcnt)) { pr_info("Waiting for family %u to become free: refcnt=%d.\n", fent->fid, atomic_read(&fent->refcnt)); if (msleep_interruptible(1000)) flush_signals(current); } } /* * Should be called under w1_flock held. */ struct w1_family * w1_family_registered(u8 fid) { struct list_head *ent, *n; struct w1_family *f = NULL; int ret = 0; list_for_each_safe(ent, n, &w1_families) { f = list_entry(ent, struct w1_family, family_entry); if (f->fid == fid) { ret = 1; break; } } return (ret) ? f : NULL; } static void __w1_family_put(struct w1_family *f) { atomic_dec(&f->refcnt); } void w1_family_put(struct w1_family *f) { spin_lock(&w1_flock); __w1_family_put(f); spin_unlock(&w1_flock); } #if 0 void w1_family_get(struct w1_family *f) { spin_lock(&w1_flock); __w1_family_get(f); spin_unlock(&w1_flock); } #endif /* 0 */ void __w1_family_get(struct w1_family *f) { smp_mb__before_atomic(); atomic_inc(&f->refcnt); smp_mb__after_atomic(); } EXPORT_SYMBOL(w1_unregister_family); EXPORT_SYMBOL(w1_register_family); context:space:mode:
authorThomas Gleixner <tglx@linutronix.de>2017-01-31 19:03:21 +0100
committerThomas Gleixner <tglx@linutronix.de>2017-01-31 20:22:18 +0100
commitaaaec6fc755447a1d056765b11b24d8ff2b81366 (patch)
treea7f4167960ee1df86739905b6ccdeb95465bfe5f /net/ieee802154/sysfs.h
parent08d85f3ea99f1eeafc4e8507936190e86a16ee8c (diff)
x86/irq: Make irq activate operations symmetric
The recent commit which prevents double activation of interrupts unearthed interesting code in x86. The code (ab)uses irq_domain_activate_irq() to reconfigure an already activated interrupt. That trips over the prevention code now. Fix it by deactivating the interrupt before activating the new configuration. Fixes: 08d85f3ea99f1 "irqdomain: Avoid activating interrupts more than once" Reported-and-tested-by: Mike Galbraith <efault@gmx.de> Reported-and-tested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1701311901580.3457@nanos
Diffstat (limited to 'net/ieee802154/sysfs.h')