--- /dev/null
+/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil; -*-
+ * vim:expandtab:shiftwidth=4:tabstop=4:
+ *
+ * Copyright (C) 2001 Cluster File Systems, Inc. <braam@clusterfs.com>
+ *
+ * This file is part of Lustre, http://www.lustre.org.
+ *
+ * Lustre is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * Lustre 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 Lustre; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * Basic library routines.
+ *
+ */
+
+#ifndef __LIBCFS_WINNT_CFS_LOCK_H__
+#define __LIBCFS_WINNT_CFS_LOCK_H__
+
+#ifndef __LIBCFS_LIBCFS_H__
+#error Do not #include this file directly. #include <libcfs/libcfs.h> instead
+#endif
+
+#ifdef __KERNEL__
+
+
+/*
+ * nt specific part ...
+ */
+
+
+/* atomic */
+
+typedef struct { volatile int counter; } atomic_t;
+
+#define ATOMIC_INIT(i) { i }
+
+#define atomic_read(v) ((v)->counter)
+#define atomic_set(v,i) (((v)->counter) = (i))
+
+void FASTCALL atomic_add(int i, atomic_t *v);
+void FASTCALL atomic_sub(int i, atomic_t *v);
+
+int FASTCALL atomic_sub_and_test(int i, atomic_t *v);
+
+void FASTCALL atomic_inc(atomic_t *v);
+void FASTCALL atomic_dec(atomic_t *v);
+
+int FASTCALL atomic_dec_and_test(atomic_t *v);
+int FASTCALL atomic_inc_and_test(atomic_t *v);
+
+
+/* event */
+
+typedef KEVENT event_t;
+
+/*
+ * cfs_init_event
+ * To initialize the event object
+ *
+ * Arguments:
+ * event: pointer to the event object
+ * type: Non Zero: SynchronizationEvent
+ * Zero: NotificationEvent
+ * status: the initial stats of the event
+ * Non Zero: signaled
+ * Zero: un-signaled
+ *
+ * Return Value:
+ * N/A
+ *
+ * Notes:
+ * N/A
+ */
+static inline void
+ cfs_init_event(event_t *event, int type, int status)
+{
+ KeInitializeEvent(
+ event,
+ (type) ? SynchronizationEvent: NotificationEvent,
+ (status) ? TRUE : FALSE
+ );
+}
+
+/*
+ * cfs_wait_event
+ * To wait on an event to syncrhonize the process
+ *
+ * Arguments:
+ * event: pointer to the event object
+ * timeout: the timeout for waitting or 0 means infinite time.
+ *
+ * Return Value:
+ * Zero: waiting timeouts
+ * Non Zero: event signaled ...
+ *
+ * Notes:
+ * N/A
+ */
+
+static inline int64_t
+cfs_wait_event(event_t * event, int64_t timeout)
+{
+ NTSTATUS Status;
+ LARGE_INTEGER TimeOut;
+
+ TimeOut.QuadPart = -1 * (10000000/HZ) * timeout;
+
+ Status = KeWaitForSingleObject(
+ event,
+ Executive,
+ KernelMode,
+ FALSE,
+ (timeout != 0) ? (&TimeOut) : (NULL)
+ );
+
+ if (Status == STATUS_TIMEOUT) {
+ return 0;
+ }
+
+ return TRUE; // signaled case
+}
+
+/*
+ * cfs_wake_event
+ * To signal the event object
+ *
+ * Arguments:
+ * event: pointer to the event object
+ *
+ * Return Value:
+ * N/A
+ *
+ * Notes:
+ * N/A
+ */
+
+static inline int
+cfs_wake_event(event_t * event)
+{
+ return (KeSetEvent(event, 0, FALSE) != 0);
+}
+
+/*
+ * cfs_clear_event
+ * To clear/reset the status of the event object
+ *
+ * Arguments:
+ * event: pointer to the event object
+ *
+ * Return Value:
+ * N/A
+ *
+ * Notes:
+ * N/A
+ */
+
+static inline void
+cfs_clear_event(event_t * event)
+{
+ KeResetEvent(event);
+}
+
+
+/*
+ * IMPORTANT !!!!!!!!
+ *
+ * All locks' declaration are not guaranteed to be initialized,
+ * Althought some of they are initialized in Linux. All locks
+ * declared by CFS_DECL_* should be initialized explicitly.
+ */
+
+
+/*
+ * spin lock defintions / routines
+ */
+
+/*
+ * Warning:
+ *
+ * for spinlock operations, try to grab nesting acquisition of
+ * spinlock will cause dead-lock in MP system and current irql
+ * overwritten for UP system. (UP system could allow nesting spin
+ * acqisition, because it's not spin at all just raising the irql.)
+ *
+ */
+
+typedef struct spin_lock {
+
+ KSPIN_LOCK lock;
+ KIRQL irql;
+
+} spinlock_t;
+
+
+#define CFS_DECL_SPIN(name) spinlock_t name;
+#define CFS_DECL_SPIN_EXTERN(name) extern spinlock_t name;
+
+
+static inline void spin_lock_init(spinlock_t *lock)
+{
+ KeInitializeSpinLock(&(lock->lock));
+}
+
+
+static inline void spin_lock(spinlock_t *lock)
+{
+ KeAcquireSpinLock(&(lock->lock), &(lock->irql));
+}
+
+static inline void spin_unlock(spinlock_t *lock)
+{
+ KIRQL irql = lock->irql;
+ KeReleaseSpinLock(&(lock->lock), irql);
+}
+
+
+#define spin_lock_irqsave(lock, flags) do {(flags) = 0; spin_lock(lock);} while(0)
+#define spin_unlock_irqrestore(lock, flags) do {spin_unlock(lock);} while(0)
+
+
+/* There's no corresponding routine in windows kernel.
+ We must realize a light one of our own. But there's
+ no way to identify the system is MP build or UP build
+ on the runtime. We just uses a workaround for it. */
+
+extern int MPSystem;
+
+static int spin_trylock(spinlock_t *lock)
+{
+ KIRQL Irql;
+ int rc = 0;
+
+ ASSERT(lock != NULL);
+
+ KeRaiseIrql(DISPATCH_LEVEL, &Irql);
+
+ if (MPSystem) {
+ if (0 == (ulong_ptr)lock->lock) {
+#if _X86_
+ __asm {
+ mov edx, dword ptr [ebp + 8]
+ lock bts dword ptr[edx], 0
+ jb lock_failed
+ mov rc, TRUE
+ lock_failed:
+ }
+#else
+ KdBreakPoint();
+#endif
+
+ }
+ } else {
+ rc = TRUE;
+ }
+
+ if (rc) {
+ lock->irql = Irql;
+ } else {
+ KeLowerIrql(Irql);
+ }
+
+ return rc;
+}
+
+/* synchronization between cpus: it will disable all DPCs
+ kernel task scheduler on the CPU */
+#define spin_lock_bh(x) spin_lock(x)
+#define spin_unlock_bh(x) spin_unlock(x)
+#define spin_lock_bh_init(x) spin_lock_init(x)
+
+/*
+ * rw_semaphore (using ERESOURCE)
+ */
+
+
+typedef struct rw_semaphore {
+ ERESOURCE rwsem;
+} rw_semaphore_t;
+
+
+#define CFS_DECL_RWSEM(name) rw_semaphore_t name
+#define CFS_DECL_RWSEM_EXTERN(name) extern rw_semaphore_t name
+
+
+/*
+ * init_rwsem
+ * To initialize the the rw_semaphore_t structure
+ *
+ * Arguments:
+ * rwsem: pointer to the rw_semaphore_t structure
+ *
+ * Return Value:
+ * N/A
+ *
+ * Notes:
+ * N/A
+ */
+
+static inline void init_rwsem(rw_semaphore_t *s)
+{
+ ExInitializeResourceLite(&s->rwsem);
+}
+
+
+/*
+ * fini_rwsem
+ * To finilize/destroy the the rw_semaphore_t structure
+ *
+ * Arguments:
+ * rwsem: pointer to the rw_semaphore_t structure
+ *
+ * Return Value:
+ * N/A
+ *
+ * Notes:
+ * For winnt system, we need this routine to delete the ERESOURCE.
+ * Just define it NULL for other systems.
+ */
+
+static inline void fini_rwsem(rw_semaphore_t *s)
+{
+ ExDeleteResourceLite(&s->rwsem);
+}
+
+/*
+ * down_read
+ * To acquire read-lock of the rw_semahore
+ *
+ * Arguments:
+ * rwsem: pointer to the rw_semaphore_t structure
+ *
+ * Return Value:
+ * N/A
+ *
+ * Notes:
+ * N/A
+ */
+
+static inline void down_read(struct rw_semaphore *s)
+{
+ ExAcquireResourceSharedLite(&s->rwsem, TRUE);
+}
+
+
+/*
+ * down_read_trylock
+ * To acquire read-lock of the rw_semahore without blocking
+ *
+ * Arguments:
+ * rwsem: pointer to the rw_semaphore_t structure
+ *
+ * Return Value:
+ * Zero: failed to acquire the read lock
+ * Non-Zero: succeeded to acquire the read lock
+ *
+ * Notes:
+ * This routine will return immediately without waiting.
+ */
+
+static inline int down_read_trylock(struct rw_semaphore *s)
+{
+ return ExAcquireResourceSharedLite(&s->rwsem, FALSE);
+}
+
+
+/*
+ * down_write
+ * To acquire write-lock of the rw_semahore
+ *
+ * Arguments:
+ * rwsem: pointer to the rw_semaphore_t structure
+ *
+ * Return Value:
+ * N/A
+ *
+ * Notes:
+ * N/A
+ */
+
+static inline void down_write(struct rw_semaphore *s)
+{
+ ExAcquireResourceExclusiveLite(&(s->rwsem), TRUE);
+}
+
+
+/*
+ * down_write_trylock
+ * To acquire write-lock of the rw_semahore without blocking
+ *
+ * Arguments:
+ * rwsem: pointer to the rw_semaphore_t structure
+ *
+ * Return Value:
+ * Zero: failed to acquire the write lock
+ * Non-Zero: succeeded to acquire the read lock
+ *
+ * Notes:
+ * This routine will return immediately without waiting.
+ */
+
+static inline int down_write_trylock(struct rw_semaphore *s)
+{
+ return ExAcquireResourceExclusiveLite(&(s->rwsem), FALSE);
+}
+
+
+/*
+ * up_read
+ * To release read-lock of the rw_semahore
+ *
+ * Arguments:
+ * rwsem: pointer to the rw_semaphore_t structure
+ *
+ * Return Value:
+ * N/A
+ *
+ * Notes:
+ * N/A
+ */
+
+static inline void up_read(struct rw_semaphore *s)
+{
+ ExReleaseResourceForThreadLite(
+ &(s->rwsem),
+ ExGetCurrentResourceThread());
+}
+
+
+/*
+ * up_write
+ * To release write-lock of the rw_semahore
+ *
+ * Arguments:
+ * rwsem: pointer to the rw_semaphore_t structure
+ *
+ * Return Value:
+ * N/A
+ *
+ * Notes:
+ * N/A
+ */
+
+static inline void up_write(struct rw_semaphore *s)
+{
+ ExReleaseResourceForThreadLite(
+ &(s->rwsem),
+ ExGetCurrentResourceThread());
+}
+
+/*
+ * rwlock_t (using sempahore)
+ *
+ * - rwlock_init(x)
+ * - read_lock(x)
+ * - read_unlock(x)
+ * - write_lock(x)
+ * - write_unlock(x)
+ */
+
+typedef struct {
+ spinlock_t guard;
+ int count;
+} rwlock_t;
+
+void rwlock_init(rwlock_t * rwlock);
+void rwlock_fini(rwlock_t * rwlock);
+
+void read_lock(rwlock_t * rwlock);
+void read_unlock(rwlock_t * rwlock);
+void write_lock(rwlock_t * rwlock);
+void write_unlock(rwlock_t * rwlock);
+
+#define write_lock_irqsave(l, f) do {f = 0; write_lock(l);} while(0)
+#define write_unlock_irqrestore(l, f) do {write_unlock(l);} while(0)
+#define read_lock_irqsave(l, f) do {f=0; read_lock(l);} while(0)
+#define read_unlock_irqrestore(l, f) do {read_unlock(l);} while(0)
+
+
+/*
+ * Semaphore
+ *
+ * - sema_init(x, v)
+ * - __down(x)
+ * - __up(x)
+ */
+
+typedef struct semaphore {
+ KSEMAPHORE sem;
+} mutex_t;
+
+static inline void sema_init(struct semaphore *s, int val)
+{
+ KeInitializeSemaphore(&s->sem, val, val);
+}
+
+static inline void __down(struct semaphore *s)
+{
+ KeWaitForSingleObject( &(s->sem), Executive,
+ KernelMode, FALSE, NULL );
+
+}
+
+static inline void __up(struct semaphore *s)
+{
+ KeReleaseSemaphore(&s->sem, 0, 1, FALSE);
+}
+
+/*
+ * mutex_t:
+ *
+ * - init_mutex(x)
+ * - init_mutex_locked(x)
+ * - mutex_up(x)
+ * - mutex_down(x)
+ */
+
+
+/*
+ * init_mutex
+ * To initialize a mutex_t structure
+ *
+ * Arguments:
+ * mutex: pointer to the mutex_t structure
+ *
+ * Return Value:
+ * N/A
+ *
+ * Notes:
+ * N/A
+ */
+
+static inline void init_mutex(mutex_t *mutex)
+{
+ sema_init(mutex, 1);
+}
+
+
+/*
+ * mutex_down
+ * To acquire the mutex lock
+ *
+ * Arguments:
+ * mutex: pointer to the mutex_t structure
+ *
+ * Return Value:
+ * N/A
+ *
+ * Notes:
+ * N/A
+ */
+
+static inline void mutex_down(mutex_t *mutex)
+{
+ __down(mutex);
+}
+
+
+/*
+ * mutex_up
+ * To release the mutex lock (acquired already)
+ *
+ * Arguments:
+ * mutex: pointer to the mutex_t structure
+ *
+ * Return Value:
+ * N/A
+ *
+ * Notes:
+ * N/A
+ */
+
+static inline void mutex_up(mutex_t *mutex)
+{
+ __up(mutex);
+}
+
+
+/*
+ * init_mutex_locked
+ * To initialize the mutex as acquired state
+ *
+ * Arguments:
+ * mutex: pointer to the mutex_t structure
+ *
+ * Return Value:
+ * N/A
+ *
+ * Notes:
+ * N/A
+ */
+
+static inline init_mutex_locked(mutex_t *mutex)
+{
+ init_mutex(mutex);
+ mutex_down(mutex);
+}
+
+/*
+ * completion
+ *
+ * - init_complition(c)
+ * - complete(c)
+ * - wait_for_completion(c)
+ */
+
+struct completion {
+ event_t event;
+};
+
+
+/*
+ * init_completion
+ * To initialize the completion object
+ *
+ * Arguments:
+ * c: pointer to the completion structure
+ *
+ * Return Value:
+ * N/A
+ *
+ * Notes:
+ * N/A
+ */
+
+static inline void init_completion(struct completion *c)
+{
+ cfs_init_event(&(c->event), 1, FALSE);
+}
+
+
+/*
+ * complete
+ * To complete/signal the completion object
+ *
+ * Arguments:
+ * c: pointer to the completion structure
+ *
+ * Return Value:
+ * N/A
+ *
+ * Notes:
+ * N/A
+ */
+
+static inline void complete(struct completion *c)
+{
+ cfs_wake_event(&(c->event));
+}
+
+/*
+ * wait_for_completion
+ * To wait on the completion object. If the event is signaled,
+ * this function will return to the call with the event un-singled.
+ *
+ * Arguments:
+ * c: pointer to the completion structure
+ *
+ * Return Value:
+ * N/A
+ *
+ * Notes:
+ * N/A
+ */
+
+static inline void wait_for_completion(struct completion *c)
+{
+ cfs_wait_event(&(c->event), 0);
+}
+
+/* __KERNEL__ */
+#else
+
+#include "../user-lock.h"
+
+/* __KERNEL__ */
+#endif
+#endif
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