/* $Id: semeventmulti-r0drv-linux.c 25951 2010-01-21 09:45:50Z vboxsync $ */ /** @file * IPRT - Multiple Release Event Semaphores, Ring-0 Driver, Linux. */ /* * Copyright (C) 2006-2007 Sun Microsystems, Inc. * * This file is part of VirtualBox Open Source Edition (OSE), as * available from http://www.virtualbox.org. This file is free software; * you can redistribute it and/or modify it under the terms of the GNU * General Public License (GPL) as published by the Free Software * Foundation, in version 2 as it comes in the "COPYING" file of the * VirtualBox OSE distribution. VirtualBox OSE is distributed in the * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind. * * The contents of this file may alternatively be used under the terms * of the Common Development and Distribution License Version 1.0 * (CDDL) only, as it comes in the "COPYING.CDDL" file of the * VirtualBox OSE distribution, in which case the provisions of the * CDDL are applicable instead of those of the GPL. * * You may elect to license modified versions of this file under the * terms and conditions of either the GPL or the CDDL or both. * * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa * Clara, CA 95054 USA or visit http://www.sun.com if you need * additional information or have any questions. */ /******************************************************************************* * Header Files * *******************************************************************************/ #include "the-linux-kernel.h" #include "internal/iprt.h" #include #include #include #include #include #include "internal/magics.h" /******************************************************************************* * Structures and Typedefs * *******************************************************************************/ /** * Linux event semaphore. */ typedef struct RTSEMEVENTMULTIINTERNAL { /** Magic value (RTSEMEVENTMULTI_MAGIC). */ uint32_t volatile u32Magic; /** The object status - !0 when signaled and 0 when reset. */ uint32_t volatile fState; /** The wait queue. */ wait_queue_head_t Head; } RTSEMEVENTMULTIINTERNAL, *PRTSEMEVENTMULTIINTERNAL; RTDECL(int) RTSemEventMultiCreate(PRTSEMEVENTMULTI phEventMultiSem) { return RTSemEventMultiCreateEx(phEventMultiSem, 0 /*fFlags*/, NIL_RTLOCKVALCLASS, NULL); } RTDECL(int) RTSemEventMultiCreateEx(PRTSEMEVENTMULTI phEventMultiSem, uint32_t fFlags, RTLOCKVALCLASS hClass, const char *pszNameFmt, ...) { PRTSEMEVENTMULTIINTERNAL pThis; AssertReturn(!(fFlags & ~RTSEMEVENTMULTI_FLAGS_NO_LOCK_VAL), VERR_INVALID_PARAMETER); pThis = (PRTSEMEVENTMULTIINTERNAL)RTMemAlloc(sizeof(*pThis)); if (pThis) { pThis->u32Magic = RTSEMEVENTMULTI_MAGIC; pThis->fState = 0; init_waitqueue_head(&pThis->Head); *phEventMultiSem = pThis; return VINF_SUCCESS; } return VERR_NO_MEMORY; } RT_EXPORT_SYMBOL(RTSemEventMultiCreate); RTDECL(int) RTSemEventMultiDestroy(RTSEMEVENTMULTI hEventMultiSem) { /* * Validate input. */ PRTSEMEVENTMULTIINTERNAL pThis = (PRTSEMEVENTMULTIINTERNAL)hEventMultiSem; if (pThis == NIL_RTSEMEVENTMULTI) return VINF_SUCCESS; AssertPtrReturn(pThis, VERR_INVALID_PARAMETER); AssertMsgReturn(pThis->u32Magic == RTSEMEVENTMULTI_MAGIC, ("%p u32Magic=%RX32\n", pThis, pThis->u32Magic), VERR_INVALID_PARAMETER); /* * Invalidate it and signal the object just in case. */ ASMAtomicWriteU32(&pThis->u32Magic, ~RTSEMEVENTMULTI_MAGIC); ASMAtomicXchgU32(&pThis->fState, 0); Assert(!waitqueue_active(&pThis->Head)); wake_up_all(&pThis->Head); RTMemFree(pThis); return VINF_SUCCESS; } RT_EXPORT_SYMBOL(RTSemEventMultiDestroy); RTDECL(int) RTSemEventMultiSignal(RTSEMEVENTMULTI hEventMultiSem) { /* * Validate input. */ PRTSEMEVENTMULTIINTERNAL pThis = (PRTSEMEVENTMULTIINTERNAL)hEventMultiSem; if (!pThis) return VERR_INVALID_PARAMETER; AssertPtrReturn(pThis, VERR_INVALID_PARAMETER); AssertMsgReturn(pThis->u32Magic == RTSEMEVENTMULTI_MAGIC, ("%p u32Magic=%RX32\n", pThis, pThis->u32Magic), VERR_INVALID_PARAMETER); /* * Signal the event object. */ ASMAtomicXchgU32(&pThis->fState, 1); wake_up_all(&pThis->Head); return VINF_SUCCESS; } RT_EXPORT_SYMBOL(RTSemEventMultiSignal); RTDECL(int) RTSemEventMultiReset(RTSEMEVENTMULTI hEventMultiSem) { /* * Validate input. */ PRTSEMEVENTMULTIINTERNAL pThis = (PRTSEMEVENTMULTIINTERNAL)hEventMultiSem; if (!pThis) return VERR_INVALID_PARAMETER; AssertPtrReturn(pThis, VERR_INVALID_PARAMETER); AssertMsgReturn(pThis->u32Magic == RTSEMEVENTMULTI_MAGIC, ("%p u32Magic=%RX32\n", pThis, pThis->u32Magic), VERR_INVALID_PARAMETER); /* * Reset it. */ ASMAtomicXchgU32(&pThis->fState, 0); return VINF_SUCCESS; } RT_EXPORT_SYMBOL(RTSemEventMultiReset); /** * Worker for RTSemEventMulti and RTSemEventMultiNoResume. * * @returns VBox status code. * @param pThis The event semaphore. * @param cMillies The number of milliseconds to wait. * @param fInterruptible Whether it's an interruptible wait or not. */ static int rtSemEventMultiWait(PRTSEMEVENTMULTIINTERNAL pThis, RTMSINTERVAL cMillies, bool fInterruptible) { /* * Ok wait for it. */ DEFINE_WAIT(Wait); int rc = VINF_SUCCESS; long lTimeout = cMillies == RT_INDEFINITE_WAIT ? MAX_SCHEDULE_TIMEOUT : msecs_to_jiffies(cMillies); #ifdef IPRT_DEBUG_SEMS snprintf(current->comm, TASK_COMM_LEN, "E%lx", IPRT_DEBUG_SEMS_ADDRESS(pThis)); #endif for (;;) { /* make everything thru schedule() atomic scheduling wise. */ prepare_to_wait(&pThis->Head, &Wait, fInterruptible ? TASK_INTERRUPTIBLE : TASK_UNINTERRUPTIBLE); /* check the condition. */ if (pThis->fState) break; /* check for pending signals. */ if (fInterruptible && signal_pending(current)) { rc = VERR_INTERRUPTED; break; } /* wait */ lTimeout = schedule_timeout(lTimeout); after_wait(&Wait); /* Check if someone destroyed the semaphore while we were waiting. */ if (pThis->u32Magic != RTSEMEVENTMULTI_MAGIC) { rc = VERR_SEM_DESTROYED; break; } /* check for timeout. */ if (!lTimeout) { rc = VERR_TIMEOUT; break; } } finish_wait(&pThis->Head, &Wait); #ifdef IPRT_DEBUG_SEMS snprintf(current->comm, TASK_COMM_LEN, "E%lx:%d", IPRT_DEBUG_SEMS_ADDRESS(pThis), rc); #endif return rc; } RTDECL(int) RTSemEventMultiWait(RTSEMEVENTMULTI hEventMultiSem, RTMSINTERVAL cMillies) { PRTSEMEVENTMULTIINTERNAL pThis = (PRTSEMEVENTMULTIINTERNAL)hEventMultiSem; if (!pThis) return VERR_INVALID_PARAMETER; AssertPtrReturn(pThis, VERR_INVALID_PARAMETER); AssertMsgReturn(pThis->u32Magic == RTSEMEVENTMULTI_MAGIC, ("%p u32Magic=%RX32\n", pThis, pThis->u32Magic), VERR_INVALID_PARAMETER); if (pThis->fState) return VINF_SUCCESS; return rtSemEventMultiWait(pThis, cMillies, false /* fInterruptible */); } RT_EXPORT_SYMBOL(RTSemEventMultiWait); RTDECL(int) RTSemEventMultiWaitNoResume(RTSEMEVENTMULTI hEventMultiSem, RTMSINTERVAL cMillies) { PRTSEMEVENTMULTIINTERNAL pThis = (PRTSEMEVENTMULTIINTERNAL)hEventMultiSem; if (!pThis) return VERR_INVALID_PARAMETER; AssertPtrReturn(pThis, VERR_INVALID_PARAMETER); AssertMsgReturn(pThis->u32Magic == RTSEMEVENTMULTI_MAGIC, ("%p u32Magic=%RX32\n", pThis, pThis->u32Magic), VERR_INVALID_PARAMETER); if (pThis->fState) return VINF_SUCCESS; return rtSemEventMultiWait(pThis, cMillies, true /* fInterruptible */); } RT_EXPORT_SYMBOL(RTSemEventMultiWaitNoResume);