diff options
Diffstat (limited to 'src/VBox/Runtime/r0drv/linux/spinlock-r0drv-linux.c')
| -rw-r--r-- | src/VBox/Runtime/r0drv/linux/spinlock-r0drv-linux.c | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/src/VBox/Runtime/r0drv/linux/spinlock-r0drv-linux.c b/src/VBox/Runtime/r0drv/linux/spinlock-r0drv-linux.c new file mode 100644 index 00000000..c5bdded2 --- /dev/null +++ b/src/VBox/Runtime/r0drv/linux/spinlock-r0drv-linux.c @@ -0,0 +1,196 @@ +/* $Id: spinlock-r0drv-linux.c $ */ +/** @file + * IPRT - Spinlocks, Ring-0 Driver, Linux. + */ + +/* + * Copyright (C) 2006-2023 Oracle and/or its affiliates. + * + * This file is part of VirtualBox base platform packages, as + * available from https://www.virtualbox.org. + * + * 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, in version 3 of the + * License. + * + * 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, see <https://www.gnu.org/licenses>. + * + * The contents of this file may alternatively be used under the terms + * of the Common Development and Distribution License Version 1.0 + * (CDDL), a copy of it is provided in the "COPYING.CDDL" file included + * in the VirtualBox 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. + * + * SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0 + */ + + +/********************************************************************************************************************************* +* Header Files * +*********************************************************************************************************************************/ +#include "the-linux-kernel.h" +#include "internal/iprt.h" +#include <iprt/spinlock.h> + +#include <iprt/asm.h> +#if defined(RT_ARCH_AMD64) || defined(RT_ARCH_X86) +# include <iprt/asm-amd64-x86.h> +#endif +#include <iprt/assert.h> +#include <iprt/errcore.h> +#include <iprt/mem.h> +#include <iprt/mp.h> +#include <iprt/thread.h> +#include "internal/magics.h" + + +/********************************************************************************************************************************* +* Structures and Typedefs * +*********************************************************************************************************************************/ +/** + * Wrapper for the spinlock_t structure. + */ +typedef struct RTSPINLOCKINTERNAL +{ + /** Spinlock magic value (RTSPINLOCK_MAGIC). */ + uint32_t volatile u32Magic; + /** The spinlock creation flags. */ + uint32_t fFlags; + /** The saved interrupt flag. */ + unsigned long volatile fIntSaved; + /** The linux spinlock structure. */ + spinlock_t Spinlock; +#ifdef RT_MORE_STRICT + /** The idAssertCpu variable before acquring the lock for asserting after + * releasing the spinlock. */ + RTCPUID volatile idAssertCpu; + /** The CPU that owns the lock. */ + RTCPUID volatile idCpuOwner; +#endif +} RTSPINLOCKINTERNAL, *PRTSPINLOCKINTERNAL; + + + +RTDECL(int) RTSpinlockCreate(PRTSPINLOCK pSpinlock, uint32_t fFlags, const char *pszName) +{ + IPRT_LINUX_SAVE_EFL_AC(); + PRTSPINLOCKINTERNAL pThis; + AssertReturn(fFlags == RTSPINLOCK_FLAGS_INTERRUPT_SAFE || fFlags == RTSPINLOCK_FLAGS_INTERRUPT_UNSAFE, VERR_INVALID_PARAMETER); + RT_NOREF_PV(pszName); + + /* + * Allocate. + */ + Assert(sizeof(RTSPINLOCKINTERNAL) > sizeof(void *)); + pThis = (PRTSPINLOCKINTERNAL)RTMemAlloc(sizeof(*pThis)); + if (!pThis) + return VERR_NO_MEMORY; + /* + * Initialize and return. + */ + pThis->u32Magic = RTSPINLOCK_MAGIC; + pThis->fFlags = fFlags; + pThis->fIntSaved = 0; +#ifdef RT_MORE_STRICT + pThis->idCpuOwner = NIL_RTCPUID; + pThis->idAssertCpu = NIL_RTCPUID; +#endif + + spin_lock_init(&pThis->Spinlock); + + *pSpinlock = pThis; + IPRT_LINUX_RESTORE_EFL_AC(); + return VINF_SUCCESS; +} +RT_EXPORT_SYMBOL(RTSpinlockCreate); + + +RTDECL(int) RTSpinlockDestroy(RTSPINLOCK Spinlock) +{ + /* + * Validate input. + */ + PRTSPINLOCKINTERNAL pThis = (PRTSPINLOCKINTERNAL)Spinlock; + if (!pThis) + return VERR_INVALID_PARAMETER; + if (pThis->u32Magic != RTSPINLOCK_MAGIC) + { + AssertMsgFailed(("Invalid spinlock %p magic=%#x\n", pThis, pThis->u32Magic)); + return VERR_INVALID_PARAMETER; + } + + ASMAtomicIncU32(&pThis->u32Magic); + RTMemFree(pThis); + return VINF_SUCCESS; +} +RT_EXPORT_SYMBOL(RTSpinlockDestroy); + + +RTDECL(void) RTSpinlockAcquire(RTSPINLOCK Spinlock) +{ + PRTSPINLOCKINTERNAL pThis = (PRTSPINLOCKINTERNAL)Spinlock; + IPRT_LINUX_SAVE_EFL_AC(); + RT_ASSERT_PREEMPT_CPUID_VAR(); + AssertMsg(pThis && pThis->u32Magic == RTSPINLOCK_MAGIC, + ("pThis=%p u32Magic=%08x\n", pThis, pThis ? (int)pThis->u32Magic : 0)); + +#ifdef CONFIG_PROVE_LOCKING + lockdep_off(); +#endif + if (pThis->fFlags & RTSPINLOCK_FLAGS_INTERRUPT_SAFE) + { + unsigned long fIntSaved; + spin_lock_irqsave(&pThis->Spinlock, fIntSaved); + pThis->fIntSaved = fIntSaved; + } + else + spin_lock(&pThis->Spinlock); +#ifdef CONFIG_PROVE_LOCKING + lockdep_on(); +#endif + + IPRT_LINUX_RESTORE_EFL_ONLY_AC(); + RT_ASSERT_PREEMPT_CPUID_SPIN_ACQUIRED(pThis); +} +RT_EXPORT_SYMBOL(RTSpinlockAcquire); + + +RTDECL(void) RTSpinlockRelease(RTSPINLOCK Spinlock) +{ + PRTSPINLOCKINTERNAL pThis = (PRTSPINLOCKINTERNAL)Spinlock; + IPRT_LINUX_SAVE_EFL_AC(); /* spin_unlock* may preempt and trash eflags.ac. */ + RT_ASSERT_PREEMPT_CPUID_SPIN_RELEASE_VARS(); + AssertMsg(pThis && pThis->u32Magic == RTSPINLOCK_MAGIC, + ("pThis=%p u32Magic=%08x\n", pThis, pThis ? (int)pThis->u32Magic : 0)); + RT_ASSERT_PREEMPT_CPUID_SPIN_RELEASE(pThis); + +#ifdef CONFIG_PROVE_LOCKING + lockdep_off(); +#endif + if (pThis->fFlags & RTSPINLOCK_FLAGS_INTERRUPT_SAFE) + { + unsigned long fIntSaved = pThis->fIntSaved; + pThis->fIntSaved = 0; + spin_unlock_irqrestore(&pThis->Spinlock, fIntSaved); + } + else + spin_unlock(&pThis->Spinlock); +#ifdef CONFIG_PROVE_LOCKING + lockdep_on(); +#endif + + IPRT_LINUX_RESTORE_EFL_ONLY_AC(); + RT_ASSERT_PREEMPT_CPUID(); +} +RT_EXPORT_SYMBOL(RTSpinlockRelease); + |