diff options
Diffstat (limited to 'src/VBox/Runtime/r0drv/solaris/threadctxhooks-r0drv-solaris.c')
| -rw-r--r-- | src/VBox/Runtime/r0drv/solaris/threadctxhooks-r0drv-solaris.c | 349 |
1 files changed, 349 insertions, 0 deletions
diff --git a/src/VBox/Runtime/r0drv/solaris/threadctxhooks-r0drv-solaris.c b/src/VBox/Runtime/r0drv/solaris/threadctxhooks-r0drv-solaris.c new file mode 100644 index 00000000..665549f0 --- /dev/null +++ b/src/VBox/Runtime/r0drv/solaris/threadctxhooks-r0drv-solaris.c @@ -0,0 +1,349 @@ +/* $Id: threadctxhooks-r0drv-solaris.c $ */ +/** @file + * IPRT - Thread Context Switching Hook, Ring-0 Driver, Solaris. + */ + +/* + * Copyright (C) 2013-2020 Oracle Corporation + * + * 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. + */ + + +/********************************************************************************************************************************* +* Header Files * +*********************************************************************************************************************************/ +#include "the-solaris-kernel.h" +#include "internal/iprt.h" + +#include <iprt/mem.h> +#include <iprt/assert.h> +#include <iprt/thread.h> +#include <iprt/errcore.h> +#include <iprt/asm.h> +#include <iprt/log.h> +#include "internal/thread.h" + + +/********************************************************************************************************************************* +* Structures and Typedefs * +*********************************************************************************************************************************/ +/** + * The internal hook object for solaris. + */ +typedef struct RTTHREADCTXHOOKINT +{ + /** Magic value (RTTHREADCTXHOOKINT_MAGIC). */ + uint32_t volatile u32Magic; + /** The thread handle (owner) for which the context-hooks are registered. */ + RTNATIVETHREAD hOwner; + /** Pointer to the registered callback function. */ + PFNRTTHREADCTXHOOK pfnCallback; + /** User argument passed to the callback function. */ + void *pvUser; + /** Whether the hook is enabled or not. */ + bool volatile fEnabled; + /** Number of references to this object. */ + uint32_t volatile cRefs; +} RTTHREADCTXHOOKINT; +typedef RTTHREADCTXHOOKINT *PRTTHREADCTXHOOKINT; + + +/********************************************************************************************************************************* +* Defined Constants And Macros * +*********************************************************************************************************************************/ +/** Validates a hook handle and returns rc if not valid. */ +#define RTTHREADCTX_VALID_RETURN_RC(pThis, rc) \ + do { \ + AssertPtrReturn((pThis), (rc)); \ + AssertReturn((pThis)->u32Magic == RTTHREADCTXHOOKINT_MAGIC, (rc)); \ + AssertReturn((pThis)->cRefs > 0, (rc)); \ + } while (0) + + +/** + * Hook function for the thread-save event. + * + * @param pvThreadCtxInt Opaque pointer to the internal hook object. + * + * @remarks Called with the with preemption disabled! + */ +static void rtThreadCtxHookSolOut(void *pvThreadCtxInt) +{ + PRTTHREADCTXHOOKINT pThis = (PRTTHREADCTXHOOKINT)pvThreadCtxInt; + AssertPtr(pThis); + Assert(!RTThreadPreemptIsEnabled(NIL_RTTHREAD)); + Assert(pThis->cRefs > 0); + + if (pThis->fEnabled) + { + Assert(pThis->pfnCallback); + pThis->pfnCallback(RTTHREADCTXEVENT_OUT, pThis->pvUser); + } +} + + +/** + * Hook function for the thread-restore event. + * + * @param pvThreadCtxInt Opaque pointer to the internal hook object. + * + * @remarks Called with preemption disabled! + */ +static void rtThreadCtxHookSolIn(void *pvThreadCtxInt) +{ + PRTTHREADCTXHOOKINT pThis = (PRTTHREADCTXHOOKINT)pvThreadCtxInt; + AssertPtr(pThis); + Assert(!RTThreadPreemptIsEnabled(NIL_RTTHREAD)); + Assert(pThis->cRefs > 0); + + if (pThis->fEnabled) + { + Assert(pThis->pfnCallback); + pThis->pfnCallback(RTTHREADCTXEVENT_IN, pThis->pvUser); + } +} + + +/** + * Hook function for the thread-free event. + * + * This is used for making sure the hook object is safely released - see + * RTThreadCtxHookRelease for details. + * + * @param pvThreadCtxInt Opaque pointer to the internal hook object. + * @param fIsExec Whether this event is triggered due to exec(). + */ +static void rtThreadCtxHookSolFree(void *pvThreadCtxInt, int fIsExec) +{ + PRTTHREADCTXHOOKINT pThis = (PRTTHREADCTXHOOKINT)pvThreadCtxInt; + AssertPtrReturnVoid(pThis); + AssertMsgReturnVoid(pThis->u32Magic == RTTHREADCTXHOOKINT_MAGIC, ("pThis->u32Magic=%RX32 pThis=%p\n", pThis->u32Magic, pThis)); + + uint32_t cRefs = ASMAtomicReadU32(&pThis->cRefs); + if (cRefs > 0) + { + cRefs = ASMAtomicDecU32(&pThis->cRefs); + if (!cRefs) + { + Assert(!pThis->fEnabled); + ASMAtomicWriteU32(&pThis->u32Magic, ~RTTHREADCTXHOOKINT_MAGIC); + RTMemFree(pThis); + } + } + else + { + /* Should never happen. */ + AssertMsgFailed(("rtThreadCtxHookSolFree with cRefs=0 pThis=%p\n", pThis)); + } +} + + +RTDECL(int) RTThreadCtxHookCreate(PRTTHREADCTXHOOK phCtxHook, uint32_t fFlags, PFNRTTHREADCTXHOOK pfnCallback, void *pvUser) +{ + /* + * Validate input. + */ + PRTTHREADCTXHOOKINT pThis; + Assert(RTThreadPreemptIsEnabled(NIL_RTTHREAD)); + AssertPtrReturn(pfnCallback, VERR_INVALID_POINTER); + AssertReturn(fFlags == 0, VERR_INVALID_FLAGS); + + /* + * Allocate and initialize a new hook. + */ + pThis = (PRTTHREADCTXHOOKINT)RTMemAllocZ(sizeof(*pThis)); + if (RT_UNLIKELY(!pThis)) + return VERR_NO_MEMORY; + pThis->u32Magic = RTTHREADCTXHOOKINT_MAGIC; + pThis->hOwner = RTThreadNativeSelf(); + pThis->pfnCallback = pfnCallback; + pThis->pvUser = pvUser; + pThis->fEnabled = false; + pThis->cRefs = 2; /* One reference for the thread, one for the caller. */ + + /* + * installctx() allocates memory and thus cannot be used in RTThreadCtxHookRegister() which can be used + * with preemption disabled. We allocate the context-hooks here and use 'fEnabled' to determine if we can + * invoke the consumer's hook or not. + */ + if (g_frtSolOldThreadCtx) + { + g_rtSolThreadCtx.Install.pfnSol_installctx_old(curthread, + pThis, + rtThreadCtxHookSolOut, /* save */ + rtThreadCtxHookSolIn, /* restore */ + NULL, /* fork */ + NULL, /* lwp_create */ + rtThreadCtxHookSolFree); + } + else + { + g_rtSolThreadCtx.Install.pfnSol_installctx(curthread, + pThis, + rtThreadCtxHookSolOut, /* save */ + rtThreadCtxHookSolIn, /* restore */ + NULL, /* fork */ + NULL, /* lwp_create */ + NULL, /* exit */ + rtThreadCtxHookSolFree); + } + + *phCtxHook = pThis; + return VINF_SUCCESS; +} + + +RTDECL(int) RTThreadCtxHookDestroy(RTTHREADCTXHOOK hCtxHook) +{ + /* + * Validate input, ignoring NIL. + */ + PRTTHREADCTXHOOKINT pThis = hCtxHook; + if (pThis == NIL_RTTHREADCTXHOOK) + return VINF_SUCCESS; + RTTHREADCTX_VALID_RETURN_RC(hCtxHook, VERR_INVALID_HANDLE); + Assert(RTThreadPreemptIsEnabled(NIL_RTTHREAD)); + Assert(!pThis->fEnabled || pThis->hOwner == RTThreadNativeSelf()); + + /* + * Make sure it's disabled. + */ + ASMAtomicWriteBool(&pThis->fEnabled, false); + + /* + * Decrement. + */ + uint32_t cRefs = ASMAtomicDecU32(&pThis->cRefs); + if ( cRefs == 1 + && pThis->hOwner == RTThreadNativeSelf()) + { + /* + * removectx() will invoke rtThreadCtxHookSolFree() and there is no way to bypass it and still use + * rtThreadCtxHookSolFree() at the same time. Hence the convulated reference counting. + * + * When this function is called from the owner thread and is the last reference, we call removectx() which + * will invoke rtThreadCtxHookSolFree() with cRefs = 1 and that will then free the hook object. + * + * When the function is called from a different thread, we simply decrement the reference. Whenever the + * ring-0 thread dies, Solaris will call rtThreadCtxHookSolFree() which will free the hook object. + */ + int rc; + if (g_frtSolOldThreadCtx) + { + rc = g_rtSolThreadCtx.Remove.pfnSol_removectx_old(curthread, + pThis, + rtThreadCtxHookSolOut, /* save */ + rtThreadCtxHookSolIn, /* restore */ + NULL, /* fork */ + NULL, /* lwp_create */ + rtThreadCtxHookSolFree); + } + else + { + rc = g_rtSolThreadCtx.Remove.pfnSol_removectx(curthread, + pThis, + rtThreadCtxHookSolOut, /* save */ + rtThreadCtxHookSolIn, /* restore */ + NULL, /* fork */ + NULL, /* lwp_create */ + NULL, /* exit */ + rtThreadCtxHookSolFree); + } + AssertMsg(rc, ("removectx() failed. rc=%d\n", rc)); + NOREF(rc); + +#if 0 /*def RT_STRICT - access after free */ + cRefs = ASMAtomicReadU32(&pThis->cRefs); + Assert(!cRefs); +#endif + cRefs = 0; + } + else if (!cRefs) + { + /* + * The ring-0 thread for this hook object has already died. Free up the object as we have no more references. + */ + Assert(pThis->hOwner != RTThreadNativeSelf()); + ASMAtomicWriteU32(&pThis->u32Magic, ~RTTHREADCTXHOOKINT_MAGIC); + RTMemFree(pThis); + } + + return cRefs; +} + + +RTDECL(int) RTThreadCtxHookEnable(RTTHREADCTXHOOK hCtxHook) +{ + /* + * Validate input. + */ + PRTTHREADCTXHOOKINT pThis = hCtxHook; + AssertPtr(pThis); + AssertMsgReturn(pThis->u32Magic == RTTHREADCTXHOOKINT_MAGIC, ("pThis->u32Magic=%RX32 pThis=%p\n", pThis->u32Magic, pThis), + VERR_INVALID_HANDLE); + Assert(pThis->hOwner == RTThreadNativeSelf()); + Assert(!pThis->fEnabled); + + /* + * Mark it as enabled. + */ + pThis->fEnabled = true; + + return VINF_SUCCESS; +} + + +RTDECL(int) RTThreadCtxHookDisable(RTTHREADCTXHOOK hCtxHook) +{ + /* + * Validate input. + */ + PRTTHREADCTXHOOKINT pThis = hCtxHook; + if (pThis != NIL_RTTHREADCTXHOOK) + { + AssertPtr(pThis); + AssertMsgReturn(pThis->u32Magic == RTTHREADCTXHOOKINT_MAGIC, ("pThis->u32Magic=%RX32 pThis=%p\n", pThis->u32Magic, pThis), + VERR_INVALID_HANDLE); + Assert(pThis->hOwner == RTThreadNativeSelf()); + + /* + * Mark it as disabled. + */ + pThis->fEnabled = false; + } + + return VINF_SUCCESS; +} + + +RTDECL(bool) RTThreadCtxHookIsEnabled(RTTHREADCTXHOOK hCtxHook) +{ + /* + * Validate input. + */ + PRTTHREADCTXHOOKINT pThis = hCtxHook; + if (pThis == NIL_RTTHREADCTXHOOK) + return false; + AssertPtr(pThis); + AssertMsgReturn(pThis->u32Magic == RTTHREADCTXHOOKINT_MAGIC, ("pThis->u32Magic=%RX32 pThis=%p\n", pThis->u32Magic, pThis), + false); + + return pThis->fEnabled; +} + |