fsync-unix-mainline.patch

From 1d3dadfd7707ac176b67b50a0dc573f799778836 Mon Sep 17 00:00:00 2001
From: Tk-Glitch <ti3nou@gmail.com>
Date: Fri, 16 Oct 2020 20:53:31 +0200
Subject: Fsync rebased 5.13+ mainline


diff --git a/dlls/ntdll/Makefile.in b/dlls/ntdll/Makefile.in
index c96a62ae006..a9be561d87a 100644
--- a/dlls/ntdll/Makefile.in
+++ b/dlls/ntdll/Makefile.in
@@ -48,6 +48,7 @@ C_SRCS = \
 	unix/env.c \
 	unix/esync.c \
 	unix/file.c \
+	unix/fsync.c \
 	unix/loader.c \
 	unix/process.c \
 	unix/registry.c \
diff --git a/dlls/ntdll/unix/esync.c b/dlls/ntdll/unix/esync.c
index ed801c71991..ac0326b1aba 100644
--- a/dlls/ntdll/unix/esync.c
+++ b/dlls/ntdll/unix/esync.c
@@ -57,6 +57,7 @@
 
 #include "unix_private.h"
 #include "esync.h"
+#include "fsync.h"
 
 WINE_DEFAULT_DEBUG_CHANNEL(esync);
 
@@ -66,7 +67,7 @@ int do_esync(void)
     static int do_esync_cached = -1;
 
     if (do_esync_cached == -1)
-        do_esync_cached = getenv("WINEESYNC") && atoi(getenv("WINEESYNC"));
+        do_esync_cached = getenv("WINEESYNC") && atoi(getenv("WINEESYNC")) && !do_fsync();
 
     return do_esync_cached;
 #else
@@ -867,7 +868,7 @@ static NTSTATUS __esync_wait_objects( DWORD count, const HANDLE *handles, BOOLEA
             return ret;
     }
 
-    if (objs[count - 1] && objs[count - 1]->type == ESYNC_QUEUE)
+    if (count && objs[count - 1] && objs[count - 1]->type == ESYNC_QUEUE)
         msgwait = TRUE;
 
     if (has_esync && has_server)
@@ -896,7 +897,7 @@ static NTSTATUS __esync_wait_objects( DWORD count, const HANDLE *handles, BOOLEA
         }
     }
 
-    if (wait_any || count == 1)
+    if (wait_any || count <= 1)
     {
         /* Try to check objects now, so we can obviate poll() at least. */
         for (i = 0; i < count; i++)
diff --git a/dlls/ntdll/unix/fsync.c b/dlls/ntdll/unix/fsync.c
new file mode 100644
index 00000000000..5012425b95a
--- /dev/null
+++ b/dlls/ntdll/unix/fsync.c
@@ -0,0 +1,1269 @@
+/*
+ * futex-based synchronization objects
+ *
+ * Copyright (C) 2018 Zebediah Figura
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+#if 0
+#pragma makedep unix
+#endif
+
+#include "config.h"
+
+#include <assert.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#ifdef HAVE_SYS_MMAN_H
+# include <sys/mman.h>
+#endif
+#ifdef HAVE_SYS_STAT_H
+# include <sys/stat.h>
+#endif
+#ifdef HAVE_SYS_SYSCALL_H
+# include <sys/syscall.h>
+#endif
+#include <unistd.h>
+
+#include "ntstatus.h"
+#define WIN32_NO_STATUS
+#define NONAMELESSUNION
+#include "windef.h"
+#include "winternl.h"
+#include "wine/debug.h"
+#include "wine/server.h"
+
+#include "unix_private.h"
+#include "fsync.h"
+
+WINE_DEFAULT_DEBUG_CHANNEL(fsync);
+
+#include "pshpack4.h"
+struct futex_wait_block
+{
+    int *addr;
+#if __SIZEOF_POINTER__ == 4
+    int pad;
+#endif
+    int val;
+    int bitset;
+};
+#include "poppack.h"
+
+static inline void small_pause(void)
+{
+#if defined(__i386__) || defined(__x86_64__)
+    __asm__ __volatile__( "rep;nop" : : : "memory" );
+#else
+    __asm__ __volatile__( "" : : : "memory" );
+#endif
+}
+
+static inline int futex_wait_multiple( const struct futex_wait_block *futexes,
+        int count, const struct timespec *timeout )
+{
+    return syscall( __NR_futex, futexes, 31, count, timeout, 0, 0 );
+}
+
+static inline int futex_wake( int *addr, int val )
+{
+    return syscall( __NR_futex, addr, 1, val, NULL, 0, 0 );
+}
+
+static inline int futex_wait( int *addr, int val, struct timespec *timeout )
+{
+    return syscall( __NR_futex, addr, 0, val, timeout, 0, 0 );
+}
+
+static unsigned int spincount = 100;
+
+int do_fsync(void)
+{
+#ifdef __linux__
+    static int do_fsync_cached = -1;
+
+    if (do_fsync_cached == -1)
+    {
+        static const struct timespec zero;
+        futex_wait_multiple( NULL, 0, &zero );
+        do_fsync_cached = getenv("WINEFSYNC") && atoi(getenv("WINEFSYNC")) && errno != ENOSYS;
+        if (getenv("WINEFSYNC_SPINCOUNT"))
+            spincount = atoi(getenv("WINEFSYNC_SPINCOUNT"));
+    }
+
+    return do_fsync_cached;
+#else
+    static int once;
+    if (!once++)
+        FIXME("futexes not supported on this platform.\n");
+    return 0;
+#endif
+}
+
+struct fsync
+{
+    enum fsync_type type;
+    void *shm;              /* pointer to shm section */
+};
+
+struct semaphore
+{
+    int count;
+    int max;
+};
+C_ASSERT(sizeof(struct semaphore) == 8);
+
+struct event
+{
+    int signaled;
+    int unused;
+};
+C_ASSERT(sizeof(struct event) == 8);
+
+struct mutex
+{
+    int tid;
+    int count;  /* recursion count */
+};
+C_ASSERT(sizeof(struct mutex) == 8);
+
+static char shm_name[29];
+static int shm_fd;
+static void **shm_addrs;
+static int shm_addrs_size;  /* length of the allocated shm_addrs array */
+static long pagesize;
+
+static pthread_mutex_t shm_addrs_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+static void *get_shm( unsigned int idx )
+{
+    int entry  = (idx * 8) / pagesize;
+    int offset = (idx * 8) % pagesize;
+    void *ret;
+
+    pthread_mutex_lock( &shm_addrs_mutex );
+
+    if (entry >= shm_addrs_size)
+    {
+        int new_size = max(shm_addrs_size * 2, entry + 1);
+
+        if (!(shm_addrs = realloc( shm_addrs, new_size * sizeof(shm_addrs[0]) )))
+            ERR("Failed to grow shm_addrs array to size %d.\n", shm_addrs_size);
+        memset( shm_addrs + shm_addrs_size, 0, (new_size - shm_addrs_size) * sizeof(shm_addrs[0]) );
+        shm_addrs_size = new_size;
+    }
+
+    if (!shm_addrs[entry])
+    {
+        void *addr = mmap( NULL, pagesize, PROT_READ | PROT_WRITE, MAP_SHARED, shm_fd, entry * pagesize );
+        if (addr == (void *)-1)
+            ERR("Failed to map page %d (offset %#lx).\n", entry, entry * pagesize);
+
+        TRACE("Mapping page %d at %p.\n", entry, addr);
+
+        if (__sync_val_compare_and_swap( &shm_addrs[entry], 0, addr ))
+            munmap( addr, pagesize ); /* someone beat us to it */
+    }
+
+    ret = (void *)((unsigned long)shm_addrs[entry] + offset);
+
+    pthread_mutex_unlock( &shm_addrs_mutex );
+
+    return ret;
+}
+
+/* We'd like lookup to be fast. To that end, we use a static list indexed by handle.
+ * This is copied and adapted from the fd cache code. */
+
+#define FSYNC_LIST_BLOCK_SIZE  (65536 / sizeof(struct fsync))
+#define FSYNC_LIST_ENTRIES     256
+
+static struct fsync *fsync_list[FSYNC_LIST_ENTRIES];
+static struct fsync fsync_list_initial_block[FSYNC_LIST_BLOCK_SIZE];
+
+static inline UINT_PTR handle_to_index( HANDLE handle, UINT_PTR *entry )
+{
+    UINT_PTR idx = (((UINT_PTR)handle) >> 2) - 1;
+    *entry = idx / FSYNC_LIST_BLOCK_SIZE;
+    return idx % FSYNC_LIST_BLOCK_SIZE;
+}
+
+static struct fsync *add_to_list( HANDLE handle, enum fsync_type type, void *shm )
+{
+    UINT_PTR entry, idx = handle_to_index( handle, &entry );
+
+    if (entry >= FSYNC_LIST_ENTRIES)
+    {
+        FIXME( "too many allocated handles, not caching %p\n", handle );
+        return FALSE;
+    }
+
+    if (!fsync_list[entry])  /* do we need to allocate a new block of entries? */
+    {
+        if (!entry) fsync_list[0] = fsync_list_initial_block;
+        else
+        {
+            void *ptr = anon_mmap_alloc( FSYNC_LIST_BLOCK_SIZE * sizeof(struct fsync),
+                                         PROT_READ | PROT_WRITE );
+            if (ptr == MAP_FAILED) return FALSE;
+            fsync_list[entry] = ptr;
+        }
+    }
+
+    if (!__sync_val_compare_and_swap((int *)&fsync_list[entry][idx].type, 0, type ))
+        fsync_list[entry][idx].shm = shm;
+
+    return &fsync_list[entry][idx];
+}
+
+static struct fsync *get_cached_object( HANDLE handle )
+{
+    UINT_PTR entry, idx = handle_to_index( handle, &entry );
+
+    if (entry >= FSYNC_LIST_ENTRIES || !fsync_list[entry]) return NULL;
+    if (!fsync_list[entry][idx].type) return NULL;
+
+    return &fsync_list[entry][idx];
+}
+
+/* Gets an object. This is either a proper fsync object (i.e. an event,
+ * semaphore, etc. created using create_fsync) or a generic synchronizable
+ * server-side object which the server will signal (e.g. a process, thread,
+ * message queue, etc.) */
+static NTSTATUS get_object( HANDLE handle, struct fsync **obj )
+{
+    NTSTATUS ret = STATUS_SUCCESS;
+    unsigned int shm_idx = 0;
+    enum fsync_type type;
+
+    if ((*obj = get_cached_object( handle ))) return STATUS_SUCCESS;
+
+    if ((INT_PTR)handle < 0)
+    {
+        /* We can deal with pseudo-handles, but it's just easier this way */
+        return STATUS_NOT_IMPLEMENTED;
+    }
+
+    /* We need to try grabbing it from the server. */
+    SERVER_START_REQ( get_fsync_idx )
+    {
+        req->handle = wine_server_obj_handle( handle );
+        if (!(ret = wine_server_call( req )))
+        {
+            shm_idx = reply->shm_idx;
+            type    = reply->type;
+        }
+    }
+    SERVER_END_REQ;
+
+    if (ret)
+    {
+        WARN("Failed to retrieve shm index for handle %p, status %#x.\n", handle, ret);
+        *obj = NULL;
+        return ret;
+    }
+
+    TRACE("Got shm index %d for handle %p.\n", shm_idx, handle);
+
+    *obj = add_to_list( handle, type, get_shm( shm_idx ) );
+    return ret;
+}
+
+NTSTATUS fsync_close( HANDLE handle )
+{
+    UINT_PTR entry, idx = handle_to_index( handle, &entry );
+
+    TRACE("%p.\n", handle);
+
+    if (entry < FSYNC_LIST_ENTRIES && fsync_list[entry])
+    {
+        if (__atomic_exchange_n( &fsync_list[entry][idx].type, 0, __ATOMIC_SEQ_CST ))
+            return STATUS_SUCCESS;
+    }
+
+    return STATUS_INVALID_HANDLE;
+}
+
+static NTSTATUS create_fsync( enum fsync_type type, HANDLE *handle,
+    ACCESS_MASK access, const OBJECT_ATTRIBUTES *attr, int low, int high )
+{
+    NTSTATUS ret;
+    data_size_t len;
+    struct object_attributes *objattr;
+    unsigned int shm_idx;
+
+    if ((ret = alloc_object_attributes( attr, &objattr, &len ))) return ret;
+
+    SERVER_START_REQ( create_fsync )
+    {
+        req->access = access;
+        req->low    = low;
+        req->high   = high;
+        req->type   = type;
+        wine_server_add_data( req, objattr, len );
+        ret = wine_server_call( req );
+        if (!ret || ret == STATUS_OBJECT_NAME_EXISTS)
+        {
+            *handle = wine_server_ptr_handle( reply->handle );
+            shm_idx = reply->shm_idx;
+            type    = reply->type;
+        }
+    }
+    SERVER_END_REQ;
+
+    if (!ret || ret == STATUS_OBJECT_NAME_EXISTS)
+    {
+        add_to_list( *handle, type, get_shm( shm_idx ));
+        TRACE("-> handle %p, shm index %d.\n", *handle, shm_idx);
+    }
+
+    free( objattr );
+    return ret;
+}
+
+static NTSTATUS open_fsync( enum fsync_type type, HANDLE *handle,
+    ACCESS_MASK access, const OBJECT_ATTRIBUTES *attr )
+{
+    NTSTATUS ret;
+    unsigned int shm_idx;
+
+    SERVER_START_REQ( open_fsync )
+    {
+        req->access     = access;
+        req->attributes = attr->Attributes;
+        req->rootdir    = wine_server_obj_handle( attr->RootDirectory );
+        req->type       = type;
+        if (attr->ObjectName)
+            wine_server_add_data( req, attr->ObjectName->Buffer, attr->ObjectName->Length );
+        if (!(ret = wine_server_call( req )))
+        {
+            *handle = wine_server_ptr_handle( reply->handle );
+            type = reply->type;
+            shm_idx = reply->shm_idx;
+        }
+    }
+    SERVER_END_REQ;
+
+    if (!ret)
+    {
+        add_to_list( *handle, type, get_shm( shm_idx ) );
+
+        TRACE("-> handle %p, shm index %u.\n", *handle, shm_idx);
+    }
+    return ret;
+}
+
+void fsync_init(void)
+{
+    struct stat st;
+
+    if (!do_fsync())
+    {
+        /* make sure the server isn't running with WINEFSYNC */
+        HANDLE handle;
+        NTSTATUS ret;
+
+        ret = create_fsync( 0, &handle, 0, NULL, 0, 0 );
+        if (ret != STATUS_NOT_IMPLEMENTED)
+        {
+            ERR("Server is running with WINEFSYNC but this process is not, please enable WINEFSYNC or restart wineserver.\n");
+            exit(1);
+        }
+
+        return;
+    }
+
+    if (stat( config_dir, &st ) == -1)
+        ERR("Cannot stat %s\n", config_dir);
+
+    if (st.st_ino != (unsigned long)st.st_ino)
+        sprintf( shm_name, "/wine-%lx%08lx-fsync", (unsigned long)((unsigned long long)st.st_ino >> 32), (unsigned long)st.st_ino );
+    else
+        sprintf( shm_name, "/wine-%lx-fsync", (unsigned long)st.st_ino );
+
+    if ((shm_fd = shm_open( shm_name, O_RDWR, 0644 )) == -1)
+    {
+        /* probably the server isn't running with WINEFSYNC, tell the user and bail */
+        if (errno == ENOENT)
+            ERR("Failed to open fsync shared memory file; make sure no stale wineserver instances are running without WINEFSYNC.\n");
+        else
+            ERR("Failed to initialize shared memory: %s\n", strerror( errno ));
+        exit(1);
+    }
+
+    pagesize = sysconf( _SC_PAGESIZE );
+
+    shm_addrs = calloc( 128, sizeof(shm_addrs[0]) );
+    shm_addrs_size = 128;
+}
+
+NTSTATUS fsync_create_semaphore( HANDLE *handle, ACCESS_MASK access,
+    const OBJECT_ATTRIBUTES *attr, LONG initial, LONG max )
+{
+    TRACE("name %s, initial %d, max %d.\n",
+        attr ? debugstr_us(attr->ObjectName) : "<no name>", initial, max);
+
+    return create_fsync( FSYNC_SEMAPHORE, handle, access, attr, initial, max );
+}
+
+NTSTATUS fsync_open_semaphore( HANDLE *handle, ACCESS_MASK access,
+    const OBJECT_ATTRIBUTES *attr )
+{
+    TRACE("name %s.\n", debugstr_us(attr->ObjectName));
+
+    return open_fsync( FSYNC_SEMAPHORE, handle, access, attr );
+}
+
+NTSTATUS fsync_release_semaphore( HANDLE handle, ULONG count, ULONG *prev )
+{
+    struct fsync *obj;
+    struct semaphore *semaphore;
+    ULONG current;
+    NTSTATUS ret;
+
+    TRACE("%p, %d, %p.\n", handle, count, prev);
+
+    if ((ret = get_object( handle, &obj ))) return ret;
+    semaphore = obj->shm;
+
+    do
+    {
+        current = semaphore->count;
+        if (count + current > semaphore->max)
+            return STATUS_SEMAPHORE_LIMIT_EXCEEDED;
+    } while (__sync_val_compare_and_swap( &semaphore->count, current, count + current ) != current);
+
+    if (prev) *prev = current;
+
+    futex_wake( &semaphore->count, INT_MAX );
+
+    return STATUS_SUCCESS;
+}
+
+NTSTATUS fsync_query_semaphore( HANDLE handle, void *info, ULONG *ret_len )
+{
+    struct fsync *obj;
+    struct semaphore *semaphore;
+    SEMAPHORE_BASIC_INFORMATION *out = info;
+    NTSTATUS ret;
+
+    TRACE("handle %p, info %p, ret_len %p.\n", handle, info, ret_len);
+
+    if ((ret = get_object( handle, &obj ))) return ret;
+    semaphore = obj->shm;
+
+    out->CurrentCount = semaphore->count;
+    out->MaximumCount = semaphore->max;
+    if (ret_len) *ret_len = sizeof(*out);
+
+    return STATUS_SUCCESS;
+}
+
+NTSTATUS fsync_create_event( HANDLE *handle, ACCESS_MASK access,
+    const OBJECT_ATTRIBUTES *attr, EVENT_TYPE event_type, BOOLEAN initial )
+{
+    enum fsync_type type = (event_type == SynchronizationEvent ? FSYNC_AUTO_EVENT : FSYNC_MANUAL_EVENT);
+
+    TRACE("name %s, %s-reset, initial %d.\n",
+        attr ? debugstr_us(attr->ObjectName) : "<no name>",
+        event_type == NotificationEvent ? "manual" : "auto", initial);
+
+    return create_fsync( type, handle, access, attr, initial, 0xdeadbeef );
+}
+
+NTSTATUS fsync_open_event( HANDLE *handle, ACCESS_MASK access,
+    const OBJECT_ATTRIBUTES *attr )
+{
+    TRACE("name %s.\n", debugstr_us(attr->ObjectName));
+
+    return open_fsync( FSYNC_AUTO_EVENT, handle, access, attr );
+}
+
+NTSTATUS fsync_set_event( HANDLE handle, LONG *prev )
+{
+    struct event *event;
+    struct fsync *obj;
+    LONG current;
+    NTSTATUS ret;
+
+    TRACE("%p.\n", handle);
+
+    if ((ret = get_object( handle, &obj ))) return ret;
+    event = obj->shm;
+
+    if (!(current = __atomic_exchange_n( &event->signaled, 1, __ATOMIC_SEQ_CST )))
+        futex_wake( &event->signaled, INT_MAX );
+
+    if (prev) *prev = current;
+
+    return STATUS_SUCCESS;
+}
+
+NTSTATUS fsync_reset_event( HANDLE handle, LONG *prev )
+{
+    struct event *event;
+    struct fsync *obj;
+    LONG current;
+    NTSTATUS ret;
+
+    TRACE("%p.\n", handle);
+
+    if ((ret = get_object( handle, &obj ))) return ret;
+    event = obj->shm;
+
+    current = __atomic_exchange_n( &event->signaled, 0, __ATOMIC_SEQ_CST );
+
+    if (prev) *prev = current;
+
+    return STATUS_SUCCESS;
+}
+
+NTSTATUS fsync_pulse_event( HANDLE handle, LONG *prev )
+{
+    struct event *event;
+    struct fsync *obj;
+    LONG current;
+    NTSTATUS ret;
+
+    TRACE("%p.\n", handle);
+
+    if ((ret = get_object( handle, &obj ))) return ret;
+    event = obj->shm;
+
+    /* This isn't really correct; an application could miss the write.
+     * Unfortunately we can't really do much better. Fortunately this is rarely
+     * used (and publicly deprecated). */
+    if (!(current = __atomic_exchange_n( &event->signaled, 1, __ATOMIC_SEQ_CST )))
+        futex_wake( &event->signaled, INT_MAX );
+
+    /* Try to give other threads a chance to wake up. Hopefully erring on this
+     * side is the better thing to do... */
+    NtYieldExecution();
+
+    __atomic_store_n( &event->signaled, 0, __ATOMIC_SEQ_CST );
+
+    if (prev) *prev = current;
+
+    return STATUS_SUCCESS;
+}
+
+NTSTATUS fsync_query_event( HANDLE handle, void *info, ULONG *ret_len )
+{
+    struct event *event;
+    struct fsync *obj;
+    EVENT_BASIC_INFORMATION *out = info;
+    NTSTATUS ret;
+
+    TRACE("handle %p, info %p, ret_len %p.\n", handle, info, ret_len);
+
+    if ((ret = get_object( handle, &obj ))) return ret;
+    event = obj->shm;
+
+    out->EventState = event->signaled;
+    out->EventType = (obj->type == FSYNC_AUTO_EVENT ? SynchronizationEvent : NotificationEvent);
+    if (ret_len) *ret_len = sizeof(*out);
+
+    return STATUS_SUCCESS;
+}
+
+NTSTATUS fsync_create_mutex( HANDLE *handle, ACCESS_MASK access,
+    const OBJECT_ATTRIBUTES *attr, BOOLEAN initial )
+{
+    TRACE("name %s, initial %d.\n",
+        attr ? debugstr_us(attr->ObjectName) : "<no name>", initial);
+
+    return create_fsync( FSYNC_MUTEX, handle, access, attr,
+        initial ? GetCurrentThreadId() : 0, initial ? 1 : 0 );
+}
+
+NTSTATUS fsync_open_mutex( HANDLE *handle, ACCESS_MASK access,
+    const OBJECT_ATTRIBUTES *attr )
+{
+    TRACE("name %s.\n", debugstr_us(attr->ObjectName));
+
+    return open_fsync( FSYNC_MUTEX, handle, access, attr );
+}
+
+NTSTATUS fsync_release_mutex( HANDLE handle, LONG *prev )
+{
+    struct mutex *mutex;
+    struct fsync *obj;
+    NTSTATUS ret;
+
+    TRACE("%p, %p.\n", handle, prev);
+
+    if ((ret = get_object( handle, &obj ))) return ret;
+    mutex = obj->shm;
+
+    if (mutex->tid != GetCurrentThreadId()) return STATUS_MUTANT_NOT_OWNED;
+
+    if (prev) *prev = mutex->count;
+
+    if (!--mutex->count)
+    {
+        __atomic_store_n( &mutex->tid, 0, __ATOMIC_SEQ_CST );
+        futex_wake( &mutex->tid, INT_MAX );
+    }
+
+    return STATUS_SUCCESS;
+}
+
+NTSTATUS fsync_query_mutex( HANDLE handle, void *info, ULONG *ret_len )
+{
+    struct fsync *obj;
+    struct mutex *mutex;
+    MUTANT_BASIC_INFORMATION *out = info;
+    NTSTATUS ret;
+
+    TRACE("handle %p, info %p, ret_len %p.\n", handle, info, ret_len);
+
+    if ((ret = get_object( handle, &obj ))) return ret;
+    mutex = obj->shm;
+
+    out->CurrentCount = 1 - mutex->count;
+    out->OwnedByCaller = (mutex->tid == GetCurrentThreadId());
+    out->AbandonedState = (mutex->tid == ~0);
+    if (ret_len) *ret_len = sizeof(*out);
+
+    return STATUS_SUCCESS;
+}
+
+static LONGLONG update_timeout( ULONGLONG end )
+{
+    LARGE_INTEGER now;
+    LONGLONG timeleft;
+
+    NtQuerySystemTime( &now );
+    timeleft = end - now.QuadPart;
+    if (timeleft < 0) timeleft = 0;
+    return timeleft;
+}
+
+static NTSTATUS do_single_wait( int *addr, int val, ULONGLONG *end, BOOLEAN alertable )
+{
+    int ret;
+
+    if (alertable)
+    {
+        int *apc_futex = ntdll_get_thread_data()->fsync_apc_futex;
+        struct futex_wait_block futexes[2];
+
+        if (__atomic_load_n( apc_futex, __ATOMIC_SEQ_CST ))
+            return STATUS_USER_APC;
+
+        futexes[0].addr = addr;
+        futexes[0].val = val;
+        futexes[1].addr = apc_futex;
+        futexes[1].val = 0;
+#if __SIZEOF_POINTER__ == 4
+        futexes[0].pad = futexes[1].pad = 0;
+#endif
+        futexes[0].bitset = futexes[1].bitset = ~0;
+
+        if (end)
+        {
+            LONGLONG timeleft = update_timeout( *end );
+            struct timespec tmo_p;
+            tmo_p.tv_sec = timeleft / (ULONGLONG)TICKSPERSEC;
+            tmo_p.tv_nsec = (timeleft % TICKSPERSEC) * 100;
+            ret = futex_wait_multiple( futexes, 2, &tmo_p );
+        }
+        else
+            ret = futex_wait_multiple( futexes, 2, NULL );
+
+        if (__atomic_load_n( apc_futex, __ATOMIC_SEQ_CST ))
+            return STATUS_USER_APC;
+    }
+    else
+    {
+        if (end)
+        {
+            LONGLONG timeleft = update_timeout( *end );
+            struct timespec tmo_p;
+            tmo_p.tv_sec = timeleft / (ULONGLONG)TICKSPERSEC;
+            tmo_p.tv_nsec = (timeleft % TICKSPERSEC) * 100;
+            ret = futex_wait( addr, val, &tmo_p );
+        }
+        else
+            ret = futex_wait( addr, val, NULL );
+    }
+
+    if (!ret)
+        return 0;
+    else if (ret < 0 && errno == ETIMEDOUT)
+        return STATUS_TIMEOUT;
+    else
+        return STATUS_PENDING;
+}
+
+static NTSTATUS __fsync_wait_objects( DWORD count, const HANDLE *handles,
+    BOOLEAN wait_any, BOOLEAN alertable, const LARGE_INTEGER *timeout )
+{
+    static const LARGE_INTEGER zero = {0};
+
+    struct futex_wait_block futexes[MAXIMUM_WAIT_OBJECTS + 1];
+    struct fsync *objs[MAXIMUM_WAIT_OBJECTS];
+    int has_fsync = 0, has_server = 0;
+    BOOL msgwait = FALSE;
+    int dummy_futex = 0;
+    unsigned int spin;
+    LONGLONG timeleft;
+    LARGE_INTEGER now;
+    DWORD waitcount;
+    ULONGLONG end;
+    int i, ret;
+
+    /* Grab the APC futex if we don't already have it. */
+    if (alertable && !ntdll_get_thread_data()->fsync_apc_futex)
+    {
+        unsigned int idx = 0;
+        SERVER_START_REQ( get_fsync_apc_idx )
+        {
+            if (!(ret = wine_server_call( req )))
+                idx = reply->shm_idx;
+        }
+        SERVER_END_REQ;
+
+        if (idx)
+        {
+            struct event *apc_event = get_shm( idx );
+            ntdll_get_thread_data()->fsync_apc_futex = &apc_event->signaled;
+        }
+    }
+
+    NtQuerySystemTime( &now );
+    if (timeout)
+    {
+        if (timeout->QuadPart == TIMEOUT_INFINITE)
+            timeout = NULL;
+        else if (timeout->QuadPart > 0)
+            end = timeout->QuadPart;
+        else
+            end = now.QuadPart - timeout->QuadPart;
+    }
+
+    for (i = 0; i < count; i++)
+    {
+        ret = get_object( handles[i], &objs[i] );
+        if (ret == STATUS_SUCCESS)
+            has_fsync = 1;
+        else if (ret == STATUS_NOT_IMPLEMENTED)
+            has_server = 1;
+        else
+            return ret;
+    }
+
+    if (count && objs[count - 1] && objs[count - 1]->type == FSYNC_QUEUE)
+        msgwait = TRUE;
+
+    if (has_fsync && has_server)
+        FIXME("Can't wait on fsync and server objects at the same time!\n");
+    else if (has_server)
+        return STATUS_NOT_IMPLEMENTED;
+
+    if (TRACE_ON(fsync))
+    {
+        TRACE("Waiting for %s of %d handles:", wait_any ? "any" : "all", count);
+        for (i = 0; i < count; i++)
+            TRACE(" %p", handles[i]);
+
+        if (msgwait)
+            TRACE(" or driver events");
+        if (alertable)
+            TRACE(", alertable");
+
+        if (!timeout)
+            TRACE(", timeout = INFINITE.\n");
+        else
+        {
+            timeleft = update_timeout( end );
+            TRACE(", timeout = %ld.%07ld sec.\n",
+                (long) (timeleft / TICKSPERSEC), (long) (timeleft % TICKSPERSEC));
+        }
+    }
+
+    if (wait_any || count <= 1)
+    {
+        while (1)
+        {
+            /* Try to grab anything. */
+
+            if (alertable)
+            {
+                /* We must check this first! The server may set an event that
+                 * we're waiting on, but we need to return STATUS_USER_APC. */
+                if (__atomic_load_n( ntdll_get_thread_data()->fsync_apc_futex, __ATOMIC_SEQ_CST ))
+                    goto userapc;
+            }
+
+            for (i = 0; i < count; i++)
+            {
+                struct fsync *obj = objs[i];
+
+                if (obj)
+                {
+                    if (!obj->type) /* gcc complains if we put this in the switch */
+                    {
+                        /* Someone probably closed an object while waiting on it. */
+                        WARN("Handle %p has type 0; was it closed?\n", handles[i]);
+                        return STATUS_INVALID_HANDLE;
+                    }
+
+                    switch (obj->type)
+                    {
+                    case FSYNC_SEMAPHORE:
+                    {
+                        struct semaphore *semaphore = obj->shm;
+                        int current;
+
+                        /* It would be a little clearer (and less error-prone)
+                         * to use a dedicated interlocked_dec_if_nonzero()
+                         * helper, but nesting loops like that is probably not
+                         * great for performance... */
+                        for (spin = 0; spin <= spincount || current; ++spin)
+                        {
+                            if ((current = __atomic_load_n( &semaphore->count, __ATOMIC_SEQ_CST ))
+                                    && __sync_val_compare_and_swap( &semaphore->count, current, current - 1 ) == current)
+                            {
+                                TRACE("Woken up by handle %p [%d].\n", handles[i], i);
+                                return i;
+                            }
+                            small_pause();
+                        }
+
+                        futexes[i].addr = &semaphore->count;
+                        futexes[i].val = 0;
+                        break;
+                    }
+                    case FSYNC_MUTEX:
+                    {
+                        struct mutex *mutex = obj->shm;
+                        int tid;
+
+                        if (mutex->tid == GetCurrentThreadId())
+                        {
+                            TRACE("Woken up by handle %p [%d].\n", handles[i], i);
+                            mutex->count++;
+                            return i;
+                        }
+
+                        for (spin = 0; spin <= spincount; ++spin)
+                        {
+                            if (!(tid = __sync_val_compare_and_swap( &mutex->tid, 0, GetCurrentThreadId() )))
+                            {
+                                TRACE("Woken up by handle %p [%d].\n", handles[i], i);
+                                mutex->count = 1;
+                                return i;
+                            }
+                            else if (tid == ~0 && (tid = __sync_val_compare_and_swap( &mutex->tid, ~0, GetCurrentThreadId() )) == ~0)
+                            {
+                                TRACE("Woken up by abandoned mutex %p [%d].\n", handles[i], i);
+                                mutex->count = 1;
+                                return STATUS_ABANDONED_WAIT_0 + i;
+                            }
+                            small_pause();
+                        }
+
+                        futexes[i].addr = &mutex->tid;
+                        futexes[i].val  = tid;
+                        break;
+                    }
+                    case FSYNC_AUTO_EVENT:
+                    case FSYNC_AUTO_SERVER:
+                    {
+                        struct event *event = obj->shm;
+
+                        for (spin = 0; spin <= spincount; ++spin)
+                        {
+                            if (__sync_val_compare_and_swap( &event->signaled, 1, 0 ))
+                            {
+                                TRACE("Woken up by handle %p [%d].\n", handles[i], i);
+                                return i;
+                            }
+                            small_pause();
+                        }
+
+                        futexes[i].addr = &event->signaled;
+                        futexes[i].val = 0;
+                        break;
+                    }
+                    case FSYNC_MANUAL_EVENT:
+                    case FSYNC_MANUAL_SERVER:
+                    case FSYNC_QUEUE:
+                    {
+                        struct event *event = obj->shm;
+
+                        for (spin = 0; spin <= spincount; ++spin)
+                        {
+                            if (__atomic_load_n( &event->signaled, __ATOMIC_SEQ_CST ))
+                            {
+                                TRACE("Woken up by handle %p [%d].\n", handles[i], i);
+                                return i;
+                            }
+                            small_pause();
+                        }
+
+                        futexes[i].addr = &event->signaled;
+                        futexes[i].val = 0;
+                        break;
+                    }
+                    default:
+                        ERR("Invalid type %#x for handle %p.\n", obj->type, handles[i]);
+                        assert(0);
+                    }
+                }
+                else
+                {
+                    /* Avoid breaking things entirely. */
+                    futexes[i].addr = &dummy_futex;
+                    futexes[i].val = dummy_futex;
+                }
+
+#if __SIZEOF_POINTER__ == 4
+                futexes[i].pad = 0;
+#endif
+                futexes[i].bitset = ~0;
+            }
+
+            if (alertable)
+            {
+                /* We already checked if it was signaled; don't bother doing it again. */
+                futexes[i].addr = ntdll_get_thread_data()->fsync_apc_futex;
+                futexes[i].val = 0;
+#if __SIZEOF_POINTER__ == 4
+                futexes[i].pad = 0;
+#endif
+                futexes[i].bitset = ~0;
+                i++;
+            }
+            waitcount = i;
+
+            /* Looks like everything is contended, so wait. */
+
+            if (timeout && !timeout->QuadPart)
+            {
+                /* Unlike esync, we already know that we've timed out, so we
+                 * can avoid a syscall. */
+                TRACE("Wait timed out.\n");
+                return STATUS_TIMEOUT;
+            }
+            else if (timeout)
+            {
+                LONGLONG timeleft = update_timeout( end );
+                struct timespec tmo_p;
+                tmo_p.tv_sec = timeleft / (ULONGLONG)TICKSPERSEC;
+                tmo_p.tv_nsec = (timeleft % TICKSPERSEC) * 100;
+
+                ret = futex_wait_multiple( futexes, waitcount, &tmo_p );
+            }
+            else
+                ret = futex_wait_multiple( futexes, waitcount, NULL );
+
+            /* FUTEX_WAIT_MULTIPLE can succeed or return -EINTR, -EAGAIN,
+             * -EFAULT/-EACCES, -ETIMEDOUT. In the first three cases we need to
+             * try again, bad address is already handled by the fact that we
+             * tried to read from it, so only break out on a timeout. */
+            if (ret == -1 && errno == ETIMEDOUT)
+            {
+                TRACE("Wait timed out.\n");
+                return STATUS_TIMEOUT;
+            }
+        } /* while (1) */
+    }
+    else
+    {
+        /* Wait-all is a little trickier to implement correctly. Fortunately,
+         * it's not as common.
+         *
+         * The idea is basically just to wait in sequence on every object in the
+         * set. Then when we're done, try to grab them all in a tight loop. If
+         * that fails, release any resources we've grabbed (and yes, we can
+         * reliably do this—it's just mutexes and semaphores that we have to
+         * put back, and in both cases we just put back 1), and if any of that
+         * fails we start over.
+         *
+         * What makes this inherently bad is that we might temporarily grab a
+         * resource incorrectly. Hopefully it'll be quick (and hey, it won't
+         * block on wineserver) so nobody will notice. Besides, consider: if
+         * object A becomes signaled but someone grabs it before we can grab it
+         * and everything else, then they could just as well have grabbed it
+         * before it became signaled. Similarly if object A was signaled and we
+         * were blocking on object B, then B becomes available and someone grabs
+         * A before we can, then they might have grabbed A before B became
+         * signaled. In either case anyone who tries to wait on A or B will be
+         * waiting for an instant while we put things back. */
+
+        NTSTATUS status = STATUS_SUCCESS;
+        int current;
+
+        while (1)
+        {
+            BOOL abandoned;
+
+tryagain:
+            abandoned = FALSE;
+
+            /* First step: try to wait on each object in sequence. */
+
+            for (i = 0; i < count; i++)
+            {
+                struct fsync *obj = objs[i];
+
+                if (obj && obj->type == FSYNC_MUTEX)
+                {
+                    struct mutex *mutex = obj->shm;
+
+                    if (mutex->tid == GetCurrentThreadId())
+                        continue;
+
+                    while ((current = __atomic_load_n( &mutex->tid, __ATOMIC_SEQ_CST )))
+                    {
+                        status = do_single_wait( &mutex->tid, current, timeout ? &end : NULL, alertable );
+                        if (status != STATUS_PENDING)
+                            break;
+                    }
+                }
+                else if (obj)
+                {
+                    /* this works for semaphores too */
+                    struct event *event = obj->shm;
+
+                    while (!__atomic_load_n( &event->signaled, __ATOMIC_SEQ_CST ))
+                    {
+                        status = do_single_wait( &event->signaled, 0, timeout ? &end : NULL, alertable );
+                        if (status != STATUS_PENDING)
+                            break;
+                    }
+                }
+
+                if (status == STATUS_TIMEOUT)
+                {
+                    TRACE("Wait timed out.\n");
+                    return status;
+                }
+                else if (status == STATUS_USER_APC)
+                    goto userapc;
+            }
+
+            /* If we got here and we haven't timed out, that means all of the
+             * handles were signaled. Check to make sure they still are. */
+            for (i = 0; i < count; i++)
+            {
+                struct fsync *obj = objs[i];
+
+                if (obj && obj->type == FSYNC_MUTEX)
+                {
+                    struct mutex *mutex = obj->shm;
+                    int tid = __atomic_load_n( &mutex->tid, __ATOMIC_SEQ_CST );
+
+                    if (tid && tid != ~0 && tid != GetCurrentThreadId())
+                        goto tryagain;
+                }
+                else if (obj)
+                {
+                    struct event *event = obj->shm;
+
+                    if (!__atomic_load_n( &event->signaled, __ATOMIC_SEQ_CST ))
+                        goto tryagain;
+                }
+            }
+
+            /* Yep, still signaled. Now quick, grab everything. */
+            for (i = 0; i < count; i++)
+            {
+                struct fsync *obj = objs[i];
+                switch (obj->type)
+                {
+                case FSYNC_MUTEX:
+                {
+                    struct mutex *mutex = obj->shm;
+                    int tid = __atomic_load_n( &mutex->tid, __ATOMIC_SEQ_CST );
+                    if (tid == GetCurrentThreadId())
+                        break;
+                    if (tid && tid != ~0)
+                        goto tooslow;
+                    if (__sync_val_compare_and_swap( &mutex->tid, tid, GetCurrentThreadId() ) != tid)
+                        goto tooslow;
+                    if (tid == ~0)
+                        abandoned = TRUE;
+                    break;
+                }
+                case FSYNC_SEMAPHORE:
+                {
+                    struct semaphore *semaphore = obj->shm;
+                    if (__sync_fetch_and_sub( &semaphore->count, 1 ) <= 0)
+                        goto tooslow;
+                    break;
+                }
+                case FSYNC_AUTO_EVENT:
+                case FSYNC_AUTO_SERVER:
+                {
+                    struct event *event = obj->shm;
+                    if (!__sync_val_compare_and_swap( &event->signaled, 1, 0 ))
+                        goto tooslow;
+                    break;
+                }
+                default:
+                    /* If a manual-reset event changed between there and
+                     * here, it's shouldn't be a problem. */
+                    break;
+                }
+            }
+
+            /* If we got here, we successfully waited on every object.
+             * Make sure to let ourselves know that we grabbed the mutexes. */
+            for (i = 0; i < count; i++)
+            {
+                if (objs[i] && objs[i]->type == FSYNC_MUTEX)
+                {
+                    struct mutex *mutex = objs[i]->shm;
+                    mutex->count++;
+                }
+            }
+
+            if (abandoned)
+            {
+                TRACE("Wait successful, but some object(s) were abandoned.\n");
+                return STATUS_ABANDONED;
+            }
+            TRACE("Wait successful.\n");
+            return STATUS_SUCCESS;
+
+tooslow:
+            for (--i; i >= 0; i--)
+            {
+                struct fsync *obj = objs[i];
+                switch (obj->type)
+                {
+                case FSYNC_MUTEX:
+                {
+                    struct mutex *mutex = obj->shm;
+                    /* HACK: This won't do the right thing with abandoned
+                     * mutexes, but fixing it is probably more trouble than
+                     * it's worth. */
+                    __atomic_store_n( &mutex->tid, 0, __ATOMIC_SEQ_CST );
+                    break;
+                }
+                case FSYNC_SEMAPHORE:
+                {
+                    struct semaphore *semaphore = obj->shm;
+                    __sync_fetch_and_add( &semaphore->count, 1 );
+                    break;
+                }
+                case FSYNC_AUTO_EVENT:
+                case FSYNC_AUTO_SERVER:
+                {
+                    struct event *event = obj->shm;
+                    __atomic_store_n( &event->signaled, 1, __ATOMIC_SEQ_CST );
+                    break;
+                }
+                default:
+                    /* doesn't need to be put back */
+                    break;
+                }
+            }
+        } /* while (1) */
+    } /* else (wait-all) */
+
+    assert(0);  /* shouldn't reach here... */
+
+userapc:
+    TRACE("Woken up by user APC.\n");
+
+    /* We have to make a server call anyway to get the APC to execute, so just
+     * delegate down to server_wait(). */
+    ret = server_wait( NULL, 0, SELECT_INTERRUPTIBLE | SELECT_ALERTABLE, &zero );
+
+    /* This can happen if we received a system APC, and the APC fd was woken up
+     * before we got SIGUSR1. poll() doesn't return EINTR in that case. The
+     * right thing to do seems to be to return STATUS_USER_APC anyway. */
+    if (ret == STATUS_TIMEOUT) ret = STATUS_USER_APC;
+    return ret;
+}
+
+/* Like esync, we need to let the server know when we are doing a message wait,
+ * and when we are done with one, so that all of the code surrounding hung
+ * queues works, and we also need this for WaitForInputIdle().
+ *
+ * Unlike esync, we can't wait on the queue fd itself locally. Instead we let
+ * the server do that for us, the way it normally does. This could actually
+ * work for esync too, and that might be better. */
+static void server_set_msgwait( int in_msgwait )
+{
+    SERVER_START_REQ( fsync_msgwait )
+    {
+        req->in_msgwait = in_msgwait;
+        wine_server_call( req );
+    }
+    SERVER_END_REQ;
+}
+
+/* This is a very thin wrapper around the proper implementation above. The
+ * purpose is to make sure the server knows when we are doing a message wait.
+ * This is separated into a wrapper function since there are at least a dozen
+ * exit paths from fsync_wait_objects(). */
+NTSTATUS fsync_wait_objects( DWORD count, const HANDLE *handles, BOOLEAN wait_any,
+                             BOOLEAN alertable, const LARGE_INTEGER *timeout )
+{
+    BOOL msgwait = FALSE;
+    struct fsync *obj;
+    NTSTATUS ret;
+
+    if (count && !get_object( handles[count - 1], &obj ) && obj->type == FSYNC_QUEUE)
+    {
+        msgwait = TRUE;
+        server_set_msgwait( 1 );
+    }
+
+    ret = __fsync_wait_objects( count, handles, wait_any, alertable, timeout );
+
+    if (msgwait)
+        server_set_msgwait( 0 );
+
+    return ret;
+}
+
+NTSTATUS fsync_signal_and_wait( HANDLE signal, HANDLE wait, BOOLEAN alertable,
+    const LARGE_INTEGER *timeout )
+{
+    struct fsync *obj;
+    NTSTATUS ret;
+
+    if ((ret = get_object( signal, &obj ))) return ret;
+
+    switch (obj->type)
+    {
+    case FSYNC_SEMAPHORE:
+        ret = fsync_release_semaphore( signal, 1, NULL );
+        break;
+    case FSYNC_AUTO_EVENT:
+    case FSYNC_MANUAL_EVENT:
+        ret = fsync_set_event( signal, NULL );
+        break;
+    case FSYNC_MUTEX:
+        ret = fsync_release_mutex( signal, NULL );
+        break;
+    default:
+        return STATUS_OBJECT_TYPE_MISMATCH;
+    }
+    if (ret) return ret;
+
+    return fsync_wait_objects( 1, &wait, TRUE, alertable, timeout );
+}
diff --git a/dlls/ntdll/unix/fsync.h b/dlls/ntdll/unix/fsync.h
new file mode 100644
index 00000000000..b3604548554
--- /dev/null
+++ b/dlls/ntdll/unix/fsync.h
@@ -0,0 +1,49 @@
+/*
+ * futex-based synchronization objects
+ *
+ * Copyright (C) 2018 Zebediah Figura
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+extern int do_fsync(void) DECLSPEC_HIDDEN;
+extern void fsync_init(void) DECLSPEC_HIDDEN;
+extern NTSTATUS fsync_close( HANDLE handle ) DECLSPEC_HIDDEN;
+
+extern NTSTATUS fsync_create_semaphore(HANDLE *handle, ACCESS_MASK access,
+    const OBJECT_ATTRIBUTES *attr, LONG initial, LONG max) DECLSPEC_HIDDEN;
+extern NTSTATUS fsync_release_semaphore( HANDLE handle, ULONG count, ULONG *prev ) DECLSPEC_HIDDEN;
+extern NTSTATUS fsync_open_semaphore( HANDLE *handle, ACCESS_MASK access,
+    const OBJECT_ATTRIBUTES *attr ) DECLSPEC_HIDDEN;
+extern NTSTATUS fsync_query_semaphore( HANDLE handle, void *info, ULONG *ret_len ) DECLSPEC_HIDDEN;
+extern NTSTATUS fsync_create_event( HANDLE *handle, ACCESS_MASK access,
+    const OBJECT_ATTRIBUTES *attr, EVENT_TYPE type, BOOLEAN initial ) DECLSPEC_HIDDEN;
+extern NTSTATUS fsync_open_event( HANDLE *handle, ACCESS_MASK access,
+    const OBJECT_ATTRIBUTES *attr ) DECLSPEC_HIDDEN;
+extern NTSTATUS fsync_set_event( HANDLE handle, LONG *prev ) DECLSPEC_HIDDEN;
+extern NTSTATUS fsync_reset_event( HANDLE handle, LONG *prev ) DECLSPEC_HIDDEN;
+extern NTSTATUS fsync_pulse_event( HANDLE handle, LONG *prev ) DECLSPEC_HIDDEN;
+extern NTSTATUS fsync_query_event( HANDLE handle, void *info, ULONG *ret_len ) DECLSPEC_HIDDEN;
+extern NTSTATUS fsync_create_mutex( HANDLE *handle, ACCESS_MASK access,
+    const OBJECT_ATTRIBUTES *attr, BOOLEAN initial ) DECLSPEC_HIDDEN;
+extern NTSTATUS fsync_open_mutex( HANDLE *handle, ACCESS_MASK access,
+    const OBJECT_ATTRIBUTES *attr ) DECLSPEC_HIDDEN;
+extern NTSTATUS fsync_release_mutex( HANDLE handle, LONG *prev ) DECLSPEC_HIDDEN;
+extern NTSTATUS fsync_query_mutex( HANDLE handle, void *info, ULONG *ret_len ) DECLSPEC_HIDDEN;
+
+extern NTSTATUS fsync_wait_objects( DWORD count, const HANDLE *handles, BOOLEAN wait_any,
+                                    BOOLEAN alertable, const LARGE_INTEGER *timeout ) DECLSPEC_HIDDEN;
+extern NTSTATUS fsync_signal_and_wait( HANDLE signal, HANDLE wait,
+    BOOLEAN alertable, const LARGE_INTEGER *timeout ) DECLSPEC_HIDDEN;
diff --git a/dlls/ntdll/unix/loader.c b/dlls/ntdll/unix/loader.c
index 19b73256ef2..d0d979248f8 100644
--- a/dlls/ntdll/unix/loader.c
+++ b/dlls/ntdll/unix/loader.c
@@ -87,6 +87,7 @@
 #include "winternl.h"
 #include "unix_private.h"
 #include "esync.h"
+#include "fsync.h"
 #include "wine/list.h"
 #include "wine/debug.h"
 
@@ -1565,6 +1566,7 @@ static void start_main_thread(void)
     dbg_init();
     server_init_process();
     startup_info_size = server_init_thread( teb->Peb, &suspend );
+    fsync_init();
     esync_init();
     virtual_map_user_shared_data();
     init_cpu_info();
diff --git a/dlls/ntdll/unix/server.c b/dlls/ntdll/unix/server.c
index 34d4c80eee5..c48a6339fee 100644
--- a/dlls/ntdll/unix/server.c
+++ b/dlls/ntdll/unix/server.c
@@ -95,6 +95,7 @@
 #include "wine/debug.h"
 #include "unix_private.h"
 #include "esync.h"
+#include "fsync.h"
 #include "ddk/wdm.h"
 
 WINE_DEFAULT_DEBUG_CHANNEL(server);
@@ -1698,6 +1699,9 @@ NTSTATUS WINAPI NtClose( HANDLE handle )
     NTSTATUS ret;
     int fd = remove_fd_from_cache( handle );
 
+    if (do_fsync())
+        fsync_close( handle );
+
     if (do_esync())
         esync_close( handle );
 
diff --git a/dlls/ntdll/unix/sync.c b/dlls/ntdll/unix/sync.c
index 051c672bd12..d8a8eb526a1 100644
--- a/dlls/ntdll/unix/sync.c
+++ b/dlls/ntdll/unix/sync.c
@@ -73,6 +73,7 @@
 #include "wine/debug.h"
 #include "unix_private.h"
 #include "esync.h"
+#include "fsync.h"
 
 WINE_DEFAULT_DEBUG_CHANNEL(sync);
 
@@ -323,6 +324,9 @@ NTSTATUS WINAPI NtCreateSemaphore( HANDLE *handle, ACCESS_MASK access, const OBJ
     if (max <= 0 || initial < 0 || initial > max) return STATUS_INVALID_PARAMETER;
     if ((ret = alloc_object_attributes( attr, &objattr, &len ))) return ret;
 
+    if (do_fsync())
+        return fsync_create_semaphore( handle, access, attr, initial, max );
+
     if (do_esync())
         return esync_create_semaphore( handle, access, attr, initial, max );
 
@@ -349,6 +353,9 @@ NTSTATUS WINAPI NtOpenSemaphore( HANDLE *handle, ACCESS_MASK access, const OBJEC
 {
     NTSTATUS ret;
 
+    if (do_fsync())
+        return fsync_open_semaphore( handle, access, attr );
+
     if (do_esync())
         return esync_open_semaphore( handle, access, attr );
 
@@ -388,6 +395,9 @@ NTSTATUS WINAPI NtQuerySemaphore( HANDLE handle, SEMAPHORE_INFORMATION_CLASS cla
 
     if (len != sizeof(SEMAPHORE_BASIC_INFORMATION)) return STATUS_INFO_LENGTH_MISMATCH;
 
+    if (do_fsync())
+        return fsync_query_semaphore( handle, info, ret_len );
+
     if (do_esync())
         return esync_query_semaphore( handle, info, ret_len );
 
@@ -413,6 +423,9 @@ NTSTATUS WINAPI NtReleaseSemaphore( HANDLE handle, ULONG count, ULONG *previous
 {
     NTSTATUS ret;
 
+    if (do_fsync())
+        return fsync_release_semaphore( handle, count, previous );
+
     if (do_esync())
         return esync_release_semaphore( handle, count, previous );
 
@@ -440,6 +453,9 @@ NTSTATUS WINAPI NtCreateEvent( HANDLE *handle, ACCESS_MASK access, const OBJECT_
     data_size_t len;
     struct object_attributes *objattr;
 
+    if (do_fsync())
+        return fsync_create_event( handle, access, attr, type, state );
+
     if (do_esync())
         return esync_create_event( handle, access, attr, type, state );
 
@@ -470,6 +486,9 @@ NTSTATUS WINAPI NtOpenEvent( HANDLE *handle, ACCESS_MASK access, const OBJECT_AT
 
     if ((ret = validate_open_object_attributes( attr ))) return ret;
 
+    if (do_fsync())
+        return fsync_open_event( handle, access, attr );
+
     if (do_esync())
         return esync_open_event( handle, access, attr );
 
@@ -495,6 +514,9 @@ NTSTATUS WINAPI NtSetEvent( HANDLE handle, LONG *prev_state )
 {
     NTSTATUS ret;
 
+    if (do_fsync())
+        return fsync_set_event( handle, prev_state );
+
     if (do_esync())
         return esync_set_event( handle );
 
@@ -517,6 +539,9 @@ NTSTATUS WINAPI NtResetEvent( HANDLE handle, LONG *prev_state )
 {
     NTSTATUS ret;
 
+    if (do_fsync())
+        return fsync_reset_event( handle, prev_state );
+
     if (do_esync())
         return esync_reset_event( handle );
 
@@ -549,6 +574,9 @@ NTSTATUS WINAPI NtPulseEvent( HANDLE handle, LONG *prev_state )
 {
     NTSTATUS ret;
 
+    if (do_fsync())
+        return fsync_pulse_event( handle, prev_state );
+
     if (do_esync())
         return esync_pulse_event( handle );
 
@@ -584,6 +612,9 @@ NTSTATUS WINAPI NtQueryEvent( HANDLE handle, EVENT_INFORMATION_CLASS class,
 
     if (len != sizeof(EVENT_BASIC_INFORMATION)) return STATUS_INFO_LENGTH_MISMATCH;
 
+    if (do_fsync())
+        return fsync_query_event( handle, info, ret_len );
+
     if (do_esync())
         return esync_query_event( handle, info, ret_len );
 
@@ -612,6 +643,9 @@ NTSTATUS WINAPI NtCreateMutant( HANDLE *handle, ACCESS_MASK access, const OBJECT
     data_size_t len;
     struct object_attributes *objattr;
 
+    if (do_fsync())
+        return fsync_create_mutex( handle, access, attr, owned );
+
     if (do_esync())
         return esync_create_mutex( handle, access, attr, owned );
 
@@ -641,6 +675,9 @@ NTSTATUS WINAPI NtOpenMutant( HANDLE *handle, ACCESS_MASK access, const OBJECT_A
 
     if ((ret = validate_open_object_attributes( attr ))) return ret;
 
+    if (do_fsync())
+        return fsync_open_mutex( handle, access, attr );
+
     if (do_esync())
         return esync_open_mutex( handle, access, attr );
 
@@ -666,6 +703,9 @@ NTSTATUS WINAPI NtReleaseMutant( HANDLE handle, LONG *prev_count )
 {
     NTSTATUS ret;
 
+    if (do_fsync())
+        return fsync_release_mutex( handle, prev_count );
+
     if (do_esync())
         return esync_release_mutex( handle, prev_count );
 
@@ -699,6 +739,9 @@ NTSTATUS WINAPI NtQueryMutant( HANDLE handle, MUTANT_INFORMATION_CLASS class,
 
     if (len != sizeof(MUTANT_BASIC_INFORMATION)) return STATUS_INFO_LENGTH_MISMATCH;
 
+    if (do_fsync())
+        return fsync_query_mutex( handle, info, ret_len );
+
     if (do_esync())
         return esync_query_mutex( handle, info, ret_len );
 
@@ -1309,6 +1352,13 @@ NTSTATUS WINAPI NtWaitForMultipleObjects( DWORD count, const HANDLE *handles, BO
 
     if (!count || count > MAXIMUM_WAIT_OBJECTS) return STATUS_INVALID_PARAMETER_1;
 
+    if (do_fsync())
+    {
+        NTSTATUS ret = fsync_wait_objects( count, handles, wait_any, alertable, timeout );
+        if (ret != STATUS_NOT_IMPLEMENTED)
+            return ret;
+    }
+
     if (do_esync())
     {
         NTSTATUS ret = esync_wait_objects( count, handles, wait_any, alertable, timeout );
@@ -1341,6 +1391,9 @@ NTSTATUS WINAPI NtSignalAndWaitForSingleObject( HANDLE signal, HANDLE wait,
     select_op_t select_op;
     UINT flags = SELECT_INTERRUPTIBLE;
 
+    if (do_fsync())
+        return fsync_signal_and_wait( signal, wait, alertable, timeout );
+
     if (do_esync())
         return esync_signal_and_wait( signal, wait, alertable, timeout );
 
@@ -1374,7 +1427,24 @@ NTSTATUS WINAPI NtYieldExecution(void)
 NTSTATUS WINAPI NtDelayExecution( BOOLEAN alertable, const LARGE_INTEGER *timeout )
 {
     /* if alertable, we need to query the server */
-    if (alertable) return server_wait( NULL, 0, SELECT_INTERRUPTIBLE | SELECT_ALERTABLE, timeout );
+    if (alertable)
+    {
+        if (do_fsync())
+        {
+            NTSTATUS ret = fsync_wait_objects( 0, NULL, TRUE, TRUE, timeout );
+            if (ret != STATUS_NOT_IMPLEMENTED)
+                return ret;
+        }
+
+        if (do_esync())
+        {
+            NTSTATUS ret = esync_wait_objects( 0, NULL, TRUE, TRUE, timeout );
+            if (ret != STATUS_NOT_IMPLEMENTED)
+                return ret;
+        }
+
+        return server_wait( NULL, 0, SELECT_INTERRUPTIBLE | SELECT_ALERTABLE, timeout );
+    }
 
     if (!timeout || timeout->QuadPart == TIMEOUT_INFINITE)  /* sleep forever */
     {
diff --git a/dlls/ntdll/unix/unix_private.h b/dlls/ntdll/unix/unix_private.h
index e7033932bcb..a2f485d892f 100644
--- a/dlls/ntdll/unix/unix_private.h
+++ b/dlls/ntdll/unix/unix_private.h
@@ -59,6 +59,7 @@ struct ntdll_thread_data
     struct debug_info *debug_info;    /* info for debugstr functions */
     void              *start_stack;   /* stack for thread startup */
     int                esync_apc_fd;  /* fd to wait on for user APCs */
+    int               *fsync_apc_futex;
     int                request_fd;    /* fd for sending server requests */
     int                reply_fd;      /* fd for receiving server replies */
     int                wait_fd[2];    /* fd for sleeping server requests */
diff --git a/dlls/ntdll/unix/virtual.c b/dlls/ntdll/unix/virtual.c
index bd89649e769..608c83b579c 100644
--- a/dlls/ntdll/unix/virtual.c
+++ b/dlls/ntdll/unix/virtual.c
@@ -2683,6 +2683,7 @@ static void init_teb( TEB *teb, PEB *peb )
     teb->StaticUnicodeString.Buffer = teb->StaticUnicodeBuffer;
     teb->StaticUnicodeString.MaximumLength = sizeof(teb->StaticUnicodeBuffer);
     thread_data->esync_apc_fd = -1;
+    thread_data->fsync_apc_futex = NULL;
     thread_data->request_fd = -1;
     thread_data->reply_fd   = -1;
     thread_data->wait_fd[0] = -1;
diff --git a/server/Makefile.in b/server/Makefile.in
index 8bd612b4728..6dc5c465e52 100644
--- a/server/Makefile.in
+++ b/server/Makefile.in
@@ -15,6 +15,7 @@ C_SRCS = \
 	event.c \
 	fd.c \
 	file.c \
+	fsync.c \
 	handle.c \
 	hook.c \
 	mach.c \
diff --git a/server/async.c b/server/async.c
index 1b4f86a1b8b..ceff9c75c27 100644
--- a/server/async.c
+++ b/server/async.c
@@ -71,6 +71,7 @@ static const struct object_ops async_ops =
     remove_queue,              /* remove_queue */
     async_signaled,            /* signaled */
     NULL,                      /* get_esync_fd */
+    NULL,                      /* get_fsync_idx */
     async_satisfied,           /* satisfied */
     no_signal,                 /* signal */
     no_get_fd,                 /* get_fd */
@@ -486,6 +487,7 @@ static const struct object_ops iosb_ops =
     NULL,                     /* remove_queue */
     NULL,                     /* signaled */
     NULL,                     /* get_esync_fd */
+    NULL,                     /* get_fsync_idx */
     NULL,                     /* satisfied */
     no_signal,                /* signal */
     no_get_fd,                /* get_fd */
diff --git a/server/atom.c b/server/atom.c
index 73d858fef82..7acef97c30d 100644
--- a/server/atom.c
+++ b/server/atom.c
@@ -81,6 +81,7 @@ static const struct object_ops atom_table_ops =
     NULL,                         /* remove_queue */
     NULL,                         /* signaled */
     NULL,                         /* get_esync_fd */
+    NULL,                         /* get_fsync_idx */
     NULL,                         /* satisfied */
     no_signal,                    /* signal */
     no_get_fd,                    /* get_fd */
diff --git a/server/change.c b/server/change.c
index 85afb0cbdc5..7eea72757c5 100644
--- a/server/change.c
+++ b/server/change.c
@@ -116,6 +116,7 @@ static const struct object_ops dir_ops =
     remove_queue,             /* remove_queue */
     default_fd_signaled,      /* signaled */
     default_fd_get_esync_fd,  /* get_esync_fd */
+    default_fd_get_fsync_idx, /* get_fsync_idx */
     no_satisfied,             /* satisfied */
     no_signal,                /* signal */
     dir_get_fd,               /* get_fd */
diff --git a/server/clipboard.c b/server/clipboard.c
index 54a5fb683cc..1fa61b67a88 100644
--- a/server/clipboard.c
+++ b/server/clipboard.c
@@ -78,6 +78,7 @@ static const struct object_ops clipboard_ops =
     NULL,                         /* remove_queue */
     NULL,                         /* signaled */
     NULL,                         /* get_esync_fd */
+    NULL,                         /* get_fsync_idx */
     NULL,                         /* satisfied */
     no_signal,                    /* signal */
     no_get_fd,                    /* get_fd */
diff --git a/server/completion.c b/server/completion.c
index ef66260c991..2149d0bbf32 100644
--- a/server/completion.c
+++ b/server/completion.c
@@ -65,6 +65,7 @@ static const struct object_ops completion_ops =
     remove_queue,              /* remove_queue */
     completion_signaled,       /* signaled */
     NULL,                      /* get_esync_fd */
+    NULL,                      /* get_fsync_idx */
     no_satisfied,              /* satisfied */
     no_signal,                 /* signal */
     no_get_fd,                 /* get_fd */
diff --git a/server/console.c b/server/console.c
index 78635f3fae1..824b930bba0 100644
--- a/server/console.c
+++ b/server/console.c
@@ -43,6 +43,7 @@
 #include "winternl.h"
 #include "wine/condrv.h"
 #include "esync.h"
+#include "fsync.h"
 
 struct screen_buffer;
 
@@ -82,6 +83,7 @@ static const struct object_ops console_input_ops =
     remove_queue,                     /* remove_queue */
     console_input_signaled,           /* signaled */
     NULL,                             /* get_esync_fd */
+    NULL,                             /* get_fsync_idx */
     no_satisfied,                     /* satisfied */
     no_signal,                        /* signal */
     console_input_get_fd,             /* get_fd */
@@ -136,6 +138,7 @@ struct console_server
     int                   term_fd;     /* UNIX terminal fd */
     struct termios        termios;     /* original termios */
     int                   esync_fd;    /* esync file descriptor */
+    unsigned int          fsync_idx;
 };
 
 static void console_server_dump( struct object *obj, int verbose );
@@ -146,6 +149,7 @@ static struct object *console_server_lookup_name( struct object *obj, struct uni
 static struct object *console_server_open_file( struct object *obj, unsigned int access,
                                                 unsigned int sharing, unsigned int options );
 static int console_server_get_esync_fd( struct object *obj, enum esync_type *type );
+static unsigned int console_server_get_fsync_idx( struct object *obj, enum fsync_type *type );
 
 static const struct object_ops console_server_ops =
 {
@@ -156,6 +160,7 @@ static const struct object_ops console_server_ops =
     remove_queue,                     /* remove_queue */
     console_server_signaled,          /* signaled */
     console_server_get_esync_fd,      /* get_esync_fd */
+    console_server_get_fsync_idx,     /* get_fsync_idx */
     no_satisfied,                     /* satisfied */
     no_signal,                        /* signal */
     console_server_get_fd,            /* get_fd */
@@ -224,6 +229,7 @@ static const struct object_ops screen_buffer_ops =
     NULL,                             /* remove_queue */
     NULL,                             /* signaled */
     NULL,                             /* get_esync_fd */
+    NULL,                             /* get_fsync_idx */
     NULL,                             /* satisfied */
     no_signal,                        /* signal */
     screen_buffer_get_fd,             /* get_fd */
@@ -272,6 +278,7 @@ static const struct object_ops console_device_ops =
     NULL,                             /* remove_queue */
     NULL,                             /* signaled */
     NULL,                             /* get_esync_fd */
+    NULL,                             /* get_fsync_idx */
     no_satisfied,                     /* satisfied */
     no_signal,                        /* signal */
     no_get_fd,                        /* get_fd */
@@ -297,6 +301,7 @@ static const struct object_ops input_device_ops =
     NULL,                             /* remove_queue */
     NULL,                             /* signaled */
     NULL,                             /* get_esync_fd */
+    NULL,                             /* get_fsync_idx */
     no_satisfied,                     /* satisfied */
     no_signal,                        /* signal */
     input_device_get_fd,              /* get_fd */
@@ -327,6 +332,7 @@ static const struct object_ops output_device_ops =
     NULL,                             /* remove_queue */
     NULL,                             /* signaled */
     NULL,                             /* get_esync_fd */
+    NULL,                             /* get_fsync_idx */
     no_satisfied,                     /* satisfied */
     no_signal,                        /* signal */
     output_device_get_fd,             /* get_fd */
@@ -365,6 +371,7 @@ static const struct object_ops console_connection_ops =
     NULL,                             /* remove_queue */
     NULL,                             /* signaled */
     NULL,                             /* get_esync_fd */
+    NULL,                             /* get_fsync_idx */
     no_satisfied,                     /* satisfied */
     no_signal,                        /* signal */
     console_connection_get_fd,        /* get_fd */
@@ -587,8 +587,13 @@ static void disconnect_console_server( struct console_server *server )
         list_remove( &call->entry );
         console_host_ioctl_terminate( call, STATUS_CANCELLED );
     }
+
+    if (do_fsync())
+        fsync_clear_futex( server->fsync_idx );
+
     if (do_esync())
         esync_clear( server->esync_fd );
+
     while (!list_empty( &server->read_queue ))
     {
         struct console_host_ioctl *call = LIST_ENTRY( list_head( &server->read_queue ), struct console_host_ioctl, entry );
@@ -774,6 +787,13 @@ static int console_server_get_esync_fd( struct object *obj, enum esync_type *typ
     return server->esync_fd;
 }
 
+static unsigned int console_server_get_fsync_idx( struct object *obj, enum fsync_type *type )
+{
+    struct console_server *server = (struct console_server*)obj;
+    *type = FSYNC_MANUAL_SERVER;
+    return server->fsync_idx;
+}
+
 static struct fd *console_server_get_fd( struct object* obj )
 {
     struct console_server *server = (struct console_server*)obj;
@@ -806,6 +828,9 @@ static struct object *create_console_server( void )
     }
     allow_fd_caching(server->fd);
 
+    if (do_fsync())
+        server->fsync_idx = fsync_alloc_shm( 0, 0 );
+
     if (do_esync())
         server->esync_fd = esync_create_fd( 0, 0 );
 
@@ -1545,6 +1560,10 @@ DECL_HANDLER(get_next_console_request)
         /* set result of previous ioctl */
         ioctl = LIST_ENTRY( list_head( &server->queue ), struct console_host_ioctl, entry );
         list_remove( &ioctl->entry );
+
+        if (do_fsync() && list_empty( &server->queue ))
+            fsync_clear_futex( server->fsync_idx );
+
         if (do_esync() && list_empty( &server->queue ))
             esync_clear( server->esync_fd );
     }
@@ -1645,6 +1664,10 @@ DECL_HANDLER(get_next_console_request)
     {
         set_error( STATUS_PENDING );
     }
+
+    if (do_fsync() && list_empty( &server->queue ))
+        fsync_clear_futex( server->fsync_idx );
+
     if (do_esync() && list_empty( &server->queue ))
         esync_clear( server->esync_fd );
 
diff --git a/server/debugger.c b/server/debugger.c
index c37f97aa0b6..b7d88cfd2f2 100644
--- a/server/debugger.c
+++ b/server/debugger.c
@@ -74,6 +74,7 @@ static const struct object_ops debug_event_ops =
     remove_queue,                  /* remove_queue */
     debug_event_signaled,          /* signaled */
     NULL,                          /* get_esync_fd */
+    NULL,                          /* get_fsync_idx */
     no_satisfied,                  /* satisfied */
     no_signal,                     /* signal */
     no_get_fd,                     /* get_fd */
@@ -103,6 +104,7 @@ static const struct object_ops debug_ctx_ops =
     remove_queue,                  /* remove_queue */
     debug_ctx_signaled,            /* signaled */
     NULL,                          /* get_esync_fd */
+    NULL,                          /* get_fsync_idx */
     no_satisfied,                  /* satisfied */
     no_signal,                     /* signal */
     no_get_fd,                     /* get_fd */
diff --git a/server/device.c b/server/device.c
index b8ce131c732..c56151c9b18 100644
--- a/server/device.c
+++ b/server/device.c
@@ -40,6 +40,7 @@
 #include "request.h"
 #include "process.h"
 #include "esync.h"
+#include "fsync.h"
 
 /* IRP object */
 
@@ -70,6 +71,7 @@ static const struct object_ops irp_call_ops =
     remove_queue,                     /* remove_queue */
     irp_call_signaled,                /* signaled */
     NULL,                             /* get_esync_fd */
+    NULL,                             /* get_fsync_idx */
     no_satisfied,                     /* satisfied */
     no_signal,                        /* signal */
     no_get_fd,                        /* get_fd */
@@ -97,11 +99,13 @@ struct device_manager
     struct irp_call       *current_call;   /* call currently executed on client side */
     struct wine_rb_tree    kernel_objects; /* map of objects that have client side pointer associated */
     int                    esync_fd;       /* esync file descriptor */
+    unsigned int           fsync_idx;
 };
 
 static void device_manager_dump( struct object *obj, int verbose );
 static int device_manager_signaled( struct object *obj, struct wait_queue_entry *entry );
 static int device_manager_get_esync_fd( struct object *obj, enum esync_type *type );
+static unsigned int device_manager_get_fsync_idx( struct object *obj, enum fsync_type *type );
 static void device_manager_destroy( struct object *obj );
 
 static const struct object_ops device_manager_ops =
@@ -113,6 +117,7 @@ static const struct object_ops device_manager_ops =
     remove_queue,                     /* remove_queue */
     device_manager_signaled,          /* signaled */
     device_manager_get_esync_fd,      /* get_esync_fd */
+    device_manager_get_fsync_idx,     /* get_fsync_idx */
     no_satisfied,                     /* satisfied */
     no_signal,                        /* signal */
     no_get_fd,                        /* get_fd */
@@ -158,6 +163,7 @@ static const struct object_ops device_ops =
     NULL,                             /* remove_queue */
     NULL,                             /* signaled */
     NULL,                             /* get_esync_fd */
+    NULL,                             /* get_fsync_idx */
     no_satisfied,                     /* satisfied */
     no_signal,                        /* signal */
     no_get_fd,                        /* get_fd */
@@ -210,6 +216,7 @@ static const struct object_ops device_file_ops =
     remove_queue,                     /* remove_queue */
     default_fd_signaled,              /* signaled */
     NULL,                             /* get_esync_fd */
+    NULL,                             /* get_fsync_idx */
     no_satisfied,                     /* satisfied */
     no_signal,                        /* signal */
     device_file_get_fd,               /* get_fd */
@@ -754,6 +761,9 @@ static void delete_file( struct device_file *file )
     /* terminate all pending requests */
     LIST_FOR_EACH_ENTRY_SAFE( irp, next, &file->requests, struct irp_call, dev_entry )
     {
+        if (do_fsync() && file->device->manager && list_empty( &file->device->manager->requests ))
+            fsync_clear( &file->device->manager->obj );
+
         if (do_esync() && file->device->manager && list_empty( &file->device->manager->requests ))
             esync_clear( file->device->manager->esync_fd );
 
@@ -799,6 +809,13 @@ static int device_manager_get_esync_fd( struct object *obj, enum esync_type *typ
     return manager->esync_fd;
 }
 
+static unsigned int device_manager_get_fsync_idx( struct object *obj, enum fsync_type *type )
+{
+    struct device_manager *manager = (struct device_manager *)obj;
+    *type = FSYNC_MANUAL_SERVER;
+    return manager->fsync_idx;
+}
+
 static void device_manager_destroy( struct object *obj )
 {
     struct device_manager *manager = (struct device_manager *)obj;
@@ -849,6 +866,9 @@ static struct device_manager *create_device_manager(void)
         list_init( &manager->requests );
         wine_rb_init( &manager->kernel_objects, compare_kernel_object );
 
+        if (do_fsync())
+            manager->fsync_idx = fsync_alloc_shm( 0, 0 );
+
         if (do_esync())
             manager->esync_fd = esync_create_fd( 0, 0 );
     }
@@ -1017,6 +1037,9 @@ DECL_HANDLER(get_next_device_request)
                 if (irp->file) grab_object( irp );
                 manager->current_call = irp;
 
+                if (do_fsync() && list_empty( &manager->requests ))
+                    fsync_clear( &manager->obj );
+
                 if (do_esync() && list_empty( &manager->requests ))
                     esync_clear( manager->esync_fd );
             }
diff --git a/server/directory.c b/server/directory.c
index 007ec1002ac..62f2e50916f 100644
--- a/server/directory.c
+++ b/server/directory.c
@@ -59,6 +59,7 @@ static const struct object_ops object_type_ops =
     NULL,                         /* remove_queue */
     NULL,                         /* signaled */
     NULL,                         /* get_esync_fd */
+    NULL,                         /* get_fsync_idx */
     NULL,                         /* satisfied */
     no_signal,                    /* signal */
     no_get_fd,                    /* get_fd */
@@ -99,6 +100,7 @@ static const struct object_ops directory_ops =
     NULL,                         /* remove_queue */
     NULL,                         /* signaled */
     NULL,                         /* get_esync_fd */
+    NULL,                         /* get_fsync_idx */
     NULL,                         /* satisfied */
     no_signal,                    /* signal */
     no_get_fd,                    /* get_fd */
diff --git a/server/esync.c b/server/esync.c
index 5c641fdbe01..6395ba4378c 100644
--- a/server/esync.c
+++ b/server/esync.c
@@ -44,6 +44,7 @@
 #include "request.h"
 #include "file.h"
 #include "esync.h"
+#include "fsync.h"
 
 int do_esync(void)
 {
@@ -51,7 +52,7 @@ int do_esync(void)
     static int do_esync_cached = -1;
 
     if (do_esync_cached == -1)
-        do_esync_cached = getenv("WINEESYNC") && atoi(getenv("WINEESYNC"));
+        do_esync_cached = getenv("WINEESYNC") && atoi(getenv("WINEESYNC")) && !do_fsync();
 
     return do_esync_cached;
 #else
@@ -130,6 +131,7 @@ const struct object_ops esync_ops =
     NULL,                      /* remove_queue */
     NULL,                      /* signaled */
     esync_get_esync_fd,        /* get_esync_fd */
+    NULL,                      /* get_fsync_idx */
     NULL,                      /* satisfied */
     no_signal,                 /* signal */
     no_get_fd,                 /* get_fd */
diff --git a/server/event.c b/server/event.c
index 8607b494b6d..28a52e61d00 100644
--- a/server/event.c
+++ b/server/event.c
@@ -36,6 +36,7 @@
 #include "request.h"
 #include "security.h"
 #include "esync.h"
+#include "fsync.h"
 
 struct event
 {
@@ -44,6 +45,7 @@ struct event
     int            manual_reset;    /* is it a manual reset event? */
     int            signaled;        /* event has been signaled */
     int            esync_fd;        /* esync file descriptor */
+    unsigned int   fsync_idx;
 };
 
 static void event_dump( struct object *obj, int verbose );
@@ -51,6 +53,7 @@ static struct object_type *event_get_type( struct object *obj );
 static int event_signaled( struct object *obj, struct wait_queue_entry *entry );
 static void event_satisfied( struct object *obj, struct wait_queue_entry *entry );
 static int event_get_esync_fd( struct object *obj, enum esync_type *type );
+static unsigned int event_get_fsync_idx( struct object *obj, enum fsync_type *type );
 static unsigned int event_map_access( struct object *obj, unsigned int access );
 static int event_signal( struct object *obj, unsigned int access);
 static struct list *event_get_kernel_obj_list( struct object *obj );
@@ -65,6 +68,7 @@ static const struct object_ops event_ops =
     remove_queue,              /* remove_queue */
     event_signaled,            /* signaled */
     event_get_esync_fd,        /* get_esync_fd */
+    event_get_fsync_idx,       /* get_fsync_idx */
     event_satisfied,           /* satisfied */
     event_signal,              /* signal */
     no_get_fd,                 /* get_fd */
@@ -101,6 +105,7 @@ static const struct object_ops keyed_event_ops =
     remove_queue,                /* remove_queue */
     keyed_event_signaled,        /* signaled */
     NULL,                        /* get_esync_fd */
+    NULL,                        /* get_fsync_idx */
     no_satisfied,                /* satisfied */
     no_signal,                   /* signal */
     no_get_fd,                   /* get_fd */
@@ -133,6 +138,9 @@ struct event *create_event( struct object *root, const struct unicode_str *name,
             event->manual_reset = manual_reset;
             event->signaled     = initial_state;
 
+            if (do_fsync())
+                event->fsync_idx = fsync_alloc_shm( initial_state, 0 );
+
             if (do_esync())
                 event->esync_fd = esync_create_fd( initial_state, 0 );
         }
@@ -143,6 +151,10 @@ struct event *create_event( struct object *root, const struct unicode_str *name,
 struct event *get_event_obj( struct process *process, obj_handle_t handle, unsigned int access )
 {
     struct object *obj;
+
+    if (do_fsync() && (obj = get_handle_obj( process, handle, access, &fsync_ops)))
+        return (struct event *)obj; /* even though it's not an event */
+
     if (do_esync() && (obj = get_handle_obj( process, handle, access, &esync_ops)))
         return (struct event *)obj; /* even though it's not an event */
 
@@ -155,10 +167,19 @@ void pulse_event( struct event *event )
     /* wake up all waiters if manual reset, a single one otherwise */
     wake_up( &event->obj, !event->manual_reset );
     event->signaled = 0;
+
+    if (do_fsync())
+        fsync_clear( &event->obj );
 }
 
 void set_event( struct event *event )
 {
+    if (do_fsync() && event->obj.ops == &fsync_ops)
+    {
+        fsync_set_event( (struct fsync *)event );
+        return;
+    }
+
     if (do_esync() && event->obj.ops == &esync_ops)
     {
         esync_set_event( (struct esync *)event );
@@ -172,6 +193,12 @@ void set_event( struct event *event )
 
 void reset_event( struct event *event )
 {
+    if (do_fsync() && event->obj.ops == &fsync_ops)
+    {
+        fsync_reset_event( (struct fsync *)event );
+        return;
+    }
+
     if (do_esync() && event->obj.ops == &esync_ops)
     {
         esync_reset_event( (struct esync *)event );
@@ -179,6 +206,9 @@ void reset_event( struct event *event )
     }
     event->signaled = 0;
 
+    if (do_fsync())
+        fsync_clear( &event->obj );
+
     if (do_esync())
         esync_clear( event->esync_fd );
 }
@@ -211,6 +241,13 @@ static int event_get_esync_fd( struct object *obj, enum esync_type *type )
     return event->esync_fd;
 }
 
+static unsigned int event_get_fsync_idx( struct object *obj, enum fsync_type *type )
+{
+    struct event *event = (struct event *)obj;
+    *type = FSYNC_MANUAL_SERVER;
+    return event->fsync_idx;
+}
+
 static void event_satisfied( struct object *obj, struct wait_queue_entry *entry )
 {
     struct event *event = (struct event *)obj;
diff --git a/server/fd.c b/server/fd.c
index bbc2462163d..c558229c3c8 100644
--- a/server/fd.c
+++ b/server/fd.c
@@ -103,6 +103,7 @@
 #include "process.h"
 #include "request.h"
 #include "esync.h"
+#include "fsync.h"
 
 #include "winternl.h"
 #include "winioctl.h"
@@ -205,6 +206,7 @@ struct fd
     apc_param_t          comp_key;    /* completion key to set in completion events */
     unsigned int         comp_flags;  /* completion flags */
     int                  esync_fd;    /* esync file descriptor */
+    unsigned int         fsync_idx;   /* fsync shm index */
 };
 
 static void fd_dump( struct object *obj, int verbose );
@@ -219,6 +221,7 @@ static const struct object_ops fd_ops =
     NULL,                     /* remove_queue */
     NULL,                     /* signaled */
     NULL,                     /* get_esync_fd */
+    NULL,                     /* get_fsync_idx */
     NULL,                     /* satisfied */
     no_signal,                /* signal */
     no_get_fd,                /* get_fd */
@@ -261,6 +264,7 @@ static const struct object_ops device_ops =
     NULL,                     /* remove_queue */
     NULL,                     /* signaled */
     NULL,                     /* get_esync_fd */
+    NULL,                     /* get_fsync_idx */
     NULL,                     /* satisfied */
     no_signal,                /* signal */
     no_get_fd,                /* get_fd */
@@ -302,6 +306,7 @@ static const struct object_ops inode_ops =
     NULL,                     /* remove_queue */
     NULL,                     /* signaled */
     NULL,                     /* get_esync_fd */
+    NULL,                     /* get_fsync_idx */
     NULL,                     /* satisfied */
     no_signal,                /* signal */
     no_get_fd,                /* get_fd */
@@ -345,6 +350,7 @@ static const struct object_ops file_lock_ops =
     remove_queue,               /* remove_queue */
     file_lock_signaled,         /* signaled */
     NULL,                       /* get_esync_fd */
+    NULL,                       /* get_fsync_idx */
     no_satisfied,               /* satisfied */
     no_signal,                  /* signal */
     no_get_fd,                  /* get_fd */
@@ -1714,6 +1720,7 @@ static struct fd *alloc_fd_object(void)
     fd->completion = NULL;
     fd->comp_flags = 0;
     fd->esync_fd   = -1;
+    fd->fsync_idx  = 0;
     init_async_queue( &fd->read_q );
     init_async_queue( &fd->write_q );
     init_async_queue( &fd->wait_q );
@@ -1723,6 +1730,9 @@ static struct fd *alloc_fd_object(void)
     if (do_esync())
         fd->esync_fd = esync_create_fd( 1, 0 );
 
+    if (do_fsync())
+        fd->fsync_idx = fsync_alloc_shm( 1, 0 );
+
     if ((fd->poll_index = add_poll_user( fd )) == -1)
     {
         release_object( fd );
@@ -1756,14 +1766,19 @@ struct fd *alloc_pseudo_fd( const struct fd_ops *fd_user_ops, struct object *use
     fd->comp_flags = 0;
     fd->no_fd_status = STATUS_BAD_DEVICE_TYPE;
     fd->esync_fd   = -1;
+    fd->fsync_idx  = 0;
     init_async_queue( &fd->read_q );
     init_async_queue( &fd->write_q );
     init_async_queue( &fd->wait_q );
     list_init( &fd->inode_entry );
     list_init( &fd->locks );
 
+    if (do_fsync())
+        fd->fsync_idx = fsync_alloc_shm( 0, 0 );
+
     if (do_esync())
         fd->esync_fd = esync_create_fd( 0, 0 );
+
     return fd;
 }
 
@@ -2190,6 +2205,9 @@ void set_fd_signaled( struct fd *fd, int signaled )
     fd->signaled = signaled;
     if (signaled) wake_up( fd->user, 0 );
 
+    if (do_fsync() && !signaled)
+        fsync_clear( fd->user );
+
     if (do_esync() && !signaled)
         esync_clear( fd->esync_fd );
 }
@@ -2232,6 +2250,15 @@ int default_fd_get_esync_fd( struct object *obj, enum esync_type *type )
     return ret;
 }
 
+unsigned int default_fd_get_fsync_idx( struct object *obj, enum fsync_type *type )
+{
+    struct fd *fd = get_obj_fd( obj );
+    unsigned int ret = fd->fsync_idx;
+    *type = FSYNC_MANUAL_SERVER;
+    release_object( fd );
+    return ret;
+}
+
 /* default map_access() routine for objects that behave like an fd */
 unsigned int default_fd_map_access( struct object *obj, unsigned int access )
 {
diff --git a/server/file.c b/server/file.c
index 49c4ba32b42..829c8685d63 100644
--- a/server/file.c
+++ b/server/file.c
@@ -112,6 +112,7 @@ static const struct object_ops file_ops =
     remove_queue,                 /* remove_queue */
     default_fd_signaled,          /* signaled */
     NULL,                         /* get_esync_fd */
+    NULL,                         /* get_fsync_idx */
     no_satisfied,                 /* satisfied */
     no_signal,                    /* signal */
     file_get_fd,                  /* get_fd */
diff --git a/server/file.h b/server/file.h
index cae0ac1e395..ed030af8d8f 100644
--- a/server/file.h
+++ b/server/file.h
@@ -103,6 +103,7 @@ extern char *dup_fd_name( struct fd *root, const char *name );
 
 extern int default_fd_signaled( struct object *obj, struct wait_queue_entry *entry );
 extern int default_fd_get_esync_fd( struct object *obj, enum esync_type *type );
+extern unsigned int default_fd_get_fsync_idx( struct object *obj, enum fsync_type *type );
 extern unsigned int default_fd_map_access( struct object *obj, unsigned int access );
 extern int default_fd_get_poll_events( struct fd *fd );
 extern void default_poll_event( struct fd *fd, int event );
diff --git a/server/fsync.c b/server/fsync.c
new file mode 100644
index 00000000000..0a88ecdd3f6
--- /dev/null
+++ b/server/fsync.c
@@ -0,0 +1,527 @@
+/*
+ * futex-based synchronization objects
+ *
+ * Copyright (C) 2018 Zebediah Figura
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+#include "config.h"
+#include "wine/port.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdarg.h>
+#ifdef HAVE_SYS_MMAN_H
+# include <sys/mman.h>
+#endif
+#ifdef HAVE_SYS_STAT_H
+# include <sys/stat.h>
+#endif
+#ifdef HAVE_SYS_SYSCALL_H
+# include <sys/syscall.h>
+#endif
+#include <unistd.h>
+
+#include "ntstatus.h"
+#define WIN32_NO_STATUS
+#include "windef.h"
+#include "winternl.h"
+
+#include "handle.h"
+#include "request.h"
+#include "fsync.h"
+
+#include "pshpack4.h"
+struct futex_wait_block
+{
+    int *addr;
+#if __SIZEOF_POINTER__ == 4
+    int pad;
+#endif
+    int val;
+};
+#include "poppack.h"
+
+static inline int futex_wait_multiple( const struct futex_wait_block *futexes,
+        int count, const struct timespec *timeout )
+{
+    return syscall( __NR_futex, futexes, 31, count, timeout, 0, 0 );
+}
+
+int do_fsync(void)
+{
+#ifdef __linux__
+    static int do_fsync_cached = -1;
+
+    if (do_fsync_cached == -1)
+    {
+        static const struct timespec zero;
+        futex_wait_multiple( NULL, 0, &zero );
+        do_fsync_cached = getenv("WINEFSYNC") && atoi(getenv("WINEFSYNC")) && errno != ENOSYS;
+    }
+
+    return do_fsync_cached;
+#else
+    return 0;
+#endif
+}
+
+static char shm_name[29];
+static int shm_fd;
+static off_t shm_size;
+static void **shm_addrs;
+static int shm_addrs_size;  /* length of the allocated shm_addrs array */
+static long pagesize;
+
+static int is_fsync_initialized;
+
+static void shm_cleanup(void)
+{
+    close( shm_fd );
+    if (shm_unlink( shm_name ) == -1)
+        perror( "shm_unlink" );
+}
+
+void fsync_init(void)
+{
+    struct stat st;
+
+    if (fstat( config_dir_fd, &st ) == -1)
+        fatal_error( "cannot stat config dir\n" );
+
+    if (st.st_ino != (unsigned long)st.st_ino)
+        sprintf( shm_name, "/wine-%lx%08lx-fsync", (unsigned long)((unsigned long long)st.st_ino >> 32), (unsigned long)st.st_ino );
+    else
+        sprintf( shm_name, "/wine-%lx-fsync", (unsigned long)st.st_ino );
+
+    if (!shm_unlink( shm_name ))
+        fprintf( stderr, "fsync: warning: a previous shm file %s was not properly removed\n", shm_name );
+
+    shm_fd = shm_open( shm_name, O_RDWR | O_CREAT | O_EXCL, 0644 );
+    if (shm_fd == -1)
+        perror( "shm_open" );
+
+    pagesize = sysconf( _SC_PAGESIZE );
+
+    shm_addrs = calloc( 128, sizeof(shm_addrs[0]) );
+    shm_addrs_size = 128;
+
+    shm_size = pagesize;
+    if (ftruncate( shm_fd, shm_size ) == -1)
+        perror( "ftruncate" );
+
+    is_fsync_initialized = 1;
+
+    fprintf( stderr, "fsync: up and running.\n" );
+
+    atexit( shm_cleanup );
+}
+
+static struct list mutex_list = LIST_INIT(mutex_list);
+
+struct fsync
+{
+    struct object  obj;
+    unsigned int   shm_idx;
+    enum fsync_type type;
+    struct list     mutex_entry;
+};
+
+static void fsync_dump( struct object *obj, int verbose );
+static unsigned int fsync_get_fsync_idx( struct object *obj, enum fsync_type *type );
+static unsigned int fsync_map_access( struct object *obj, unsigned int access );
+static void fsync_destroy( struct object *obj );
+
+const struct object_ops fsync_ops =
+{
+    sizeof(struct fsync),      /* size */
+    fsync_dump,                /* dump */
+    no_get_type,               /* get_type */
+    no_add_queue,              /* add_queue */
+    NULL,                      /* remove_queue */
+    NULL,                      /* signaled */
+    NULL,                      /* get_esync_fd */
+    fsync_get_fsync_idx,       /* get_fsync_idx */
+    NULL,                      /* satisfied */
+    no_signal,                 /* signal */
+    no_get_fd,                 /* get_fd */
+    fsync_map_access,          /* map_access */
+    default_get_sd,            /* get_sd */
+    default_set_sd,            /* set_sd */
+    no_get_full_name,          /* get_full_name */
+    no_lookup_name,            /* lookup_name */
+    directory_link_name,       /* link_name */
+    default_unlink_name,       /* unlink_name */
+    no_open_file,              /* open_file */
+    no_kernel_obj_list,        /* get_kernel_obj_list */
+    no_close_handle,           /* close_handle */
+    fsync_destroy              /* destroy */
+};
+
+static void fsync_dump( struct object *obj, int verbose )
+{
+    struct fsync *fsync = (struct fsync *)obj;
+    assert( obj->ops == &fsync_ops );
+    fprintf( stderr, "fsync idx=%d\n", fsync->shm_idx );
+}
+
+static unsigned int fsync_get_fsync_idx( struct object *obj, enum fsync_type *type)
+{
+    struct fsync *fsync = (struct fsync *)obj;
+    *type = fsync->type;
+    return fsync->shm_idx;
+}
+
+static unsigned int fsync_map_access( struct object *obj, unsigned int access )
+{
+    /* Sync objects have the same flags. */
+    if (access & GENERIC_READ)    access |= STANDARD_RIGHTS_READ | EVENT_QUERY_STATE;
+    if (access & GENERIC_WRITE)   access |= STANDARD_RIGHTS_WRITE | EVENT_MODIFY_STATE;
+    if (access & GENERIC_EXECUTE) access |= STANDARD_RIGHTS_EXECUTE | SYNCHRONIZE;
+    if (access & GENERIC_ALL)     access |= STANDARD_RIGHTS_ALL | EVENT_QUERY_STATE | EVENT_MODIFY_STATE;
+    return access & ~(GENERIC_READ | GENERIC_WRITE | GENERIC_EXECUTE | GENERIC_ALL);
+}
+
+static void fsync_destroy( struct object *obj )
+{
+    struct fsync *fsync = (struct fsync *)obj;
+    if (fsync->type == FSYNC_MUTEX)
+        list_remove( &fsync->mutex_entry );
+}
+
+static void *get_shm( unsigned int idx )
+{
+    int entry  = (idx * 8) / pagesize;
+    int offset = (idx * 8) % pagesize;
+
+    if (entry >= shm_addrs_size)
+    {
+        int new_size = max(shm_addrs_size * 2, entry + 1);
+
+        if (!(shm_addrs = realloc( shm_addrs, new_size * sizeof(shm_addrs[0]) )))
+            fprintf( stderr, "fsync: couldn't expand shm_addrs array to size %d\n", entry + 1 );
+
+        memset( shm_addrs + shm_addrs_size, 0, (new_size - shm_addrs_size) * sizeof(shm_addrs[0]) );
+
+        shm_addrs_size = new_size;
+    }
+
+    if (!shm_addrs[entry])
+    {
+        void *addr = mmap( NULL, pagesize, PROT_READ | PROT_WRITE, MAP_SHARED, shm_fd, entry * pagesize );
+        if (addr == (void *)-1)
+        {
+            fprintf( stderr, "fsync: failed to map page %d (offset %#lx): ", entry, entry * pagesize );
+            perror( "mmap" );
+        }
+
+        if (debug_level)
+            fprintf( stderr, "fsync: Mapping page %d at %p.\n", entry, addr );
+
+        if (__sync_val_compare_and_swap( &shm_addrs[entry], 0, addr ))
+            munmap( addr, pagesize ); /* someone beat us to it */
+    }
+
+    return (void *)((unsigned long)shm_addrs[entry] + offset);
+}
+
+/* FIXME: This is rather inefficient... */
+static unsigned int shm_idx_counter = 1;
+
+unsigned int fsync_alloc_shm( int low, int high )
+{
+#ifdef __linux__
+    int shm_idx;
+    int *shm;
+
+    /* this is arguably a bit of a hack, but we need some way to prevent
+     * allocating shm for the master socket */
+    if (!is_fsync_initialized)
+        return 0;
+
+    shm_idx = shm_idx_counter++;
+
+    while (shm_idx * 8 >= shm_size)
+    {
+        /* Better expand the shm section. */
+        shm_size += pagesize;
+        if (ftruncate( shm_fd, shm_size ) == -1)
+        {
+            fprintf( stderr, "fsync: couldn't expand %s to size %jd: ",
+                shm_name, shm_size );
+            perror( "ftruncate" );
+        }
+    }
+
+    shm = get_shm( shm_idx );
+    assert(shm);
+    shm[0] = low;
+    shm[1] = high;
+
+    return shm_idx;
+#else
+    return 0;
+#endif
+}
+
+static int type_matches( enum fsync_type type1, enum fsync_type type2 )
+{
+    return (type1 == type2) ||
+           ((type1 == FSYNC_AUTO_EVENT || type1 == FSYNC_MANUAL_EVENT) &&
+            (type2 == FSYNC_AUTO_EVENT || type2 == FSYNC_MANUAL_EVENT));
+}
+
+struct fsync *create_fsync( struct object *root, const struct unicode_str *name,
+    unsigned int attr, int low, int high, enum fsync_type type,
+    const struct security_descriptor *sd )
+{
+#ifdef __linux__
+    struct fsync *fsync;
+
+    if ((fsync = create_named_object( root, &fsync_ops, name, attr, sd )))
+    {
+        if (get_error() != STATUS_OBJECT_NAME_EXISTS)
+        {
+            /* initialize it if it didn't already exist */
+
+            /* Initialize the shared memory portion. We want to do this on the
+             * server side to avoid a potential though unlikely race whereby
+             * the same object is opened and used between the time it's created
+             * and the time its shared memory portion is initialized. */
+
+            fsync->shm_idx = fsync_alloc_shm( low, high );
+            fsync->type = type;
+            if (type == FSYNC_MUTEX)
+                list_add_tail( &mutex_list, &fsync->mutex_entry );
+        }
+        else
+        {
+            /* validate the type */
+            if (!type_matches( type, fsync->type ))
+            {
+                release_object( &fsync->obj );
+                set_error( STATUS_OBJECT_TYPE_MISMATCH );
+                return NULL;
+            }
+        }
+    }
+
+    return fsync;
+#else
+    set_error( STATUS_NOT_IMPLEMENTED );
+    return NULL;
+#endif
+}
+
+static inline int futex_wake( int *addr, int val )
+{
+    return syscall( __NR_futex, addr, 1, val, NULL, 0, 0 );
+}
+
+/* shm layout for events or event-like objects. */
+struct fsync_event
+{
+    int signaled;
+    int unused;
+};
+
+void fsync_wake_futex( unsigned int shm_idx )
+{
+    struct fsync_event *event;
+
+    if (debug_level)
+        fprintf( stderr, "fsync_wake_futex: index %u\n", shm_idx );
+
+    if (!shm_idx)
+        return;
+
+    event = get_shm( shm_idx );
+    if (!__atomic_exchange_n( &event->signaled, 1, __ATOMIC_SEQ_CST ))
+        futex_wake( &event->signaled, INT_MAX );
+}
+
+void fsync_wake_up( struct object *obj )
+{
+    enum fsync_type type;
+
+    if (debug_level)
+        fprintf( stderr, "fsync_wake_up: object %p\n", obj );
+
+    if (obj->ops->get_fsync_idx)
+        fsync_wake_futex( obj->ops->get_fsync_idx( obj, &type ) );
+}
+
+void fsync_clear_futex( unsigned int shm_idx )
+{
+    struct fsync_event *event;
+
+    if (debug_level)
+        fprintf( stderr, "fsync_clear_futex: index %u\n", shm_idx );
+
+    if (!shm_idx)
+        return;
+
+    event = get_shm( shm_idx );
+    __atomic_store_n( &event->signaled, 0, __ATOMIC_SEQ_CST );
+}
+
+void fsync_clear( struct object *obj )
+{
+    enum fsync_type type;
+
+    if (debug_level)
+        fprintf( stderr, "fsync_clear: object %p\n", obj );
+
+    if (obj->ops->get_fsync_idx)
+        fsync_clear_futex( obj->ops->get_fsync_idx( obj, &type ) );
+}
+
+void fsync_set_event( struct fsync *fsync )
+{
+    struct fsync_event *event = get_shm( fsync->shm_idx );
+    assert( fsync->obj.ops == &fsync_ops );
+
+    if (!__atomic_exchange_n( &event->signaled, 1, __ATOMIC_SEQ_CST ))
+        futex_wake( &event->signaled, INT_MAX );
+}
+
+void fsync_reset_event( struct fsync *fsync )
+{
+    struct fsync_event *event = get_shm( fsync->shm_idx );
+    assert( fsync->obj.ops == &fsync_ops );
+
+    __atomic_store_n( &event->signaled, 0, __ATOMIC_SEQ_CST );
+}
+
+struct mutex
+{
+    int tid;
+    int count;  /* recursion count */
+};
+
+void fsync_abandon_mutexes( struct thread *thread )
+{
+    struct fsync *fsync;
+
+    LIST_FOR_EACH_ENTRY( fsync, &mutex_list, struct fsync, mutex_entry )
+    {
+        struct mutex *mutex = get_shm( fsync->shm_idx );
+
+        if (mutex->tid == thread->id)
+        {
+            if (debug_level)
+                fprintf( stderr, "fsync_abandon_mutexes() idx=%d\n", fsync->shm_idx );
+            mutex->tid = ~0;
+            mutex->count = 0;
+            futex_wake( &mutex->tid, INT_MAX );
+        }
+    }
+}
+
+DECL_HANDLER(create_fsync)
+{
+    struct fsync *fsync;
+    struct unicode_str name;
+    struct object *root;
+    const struct security_descriptor *sd;
+    const struct object_attributes *objattr = get_req_object_attributes( &sd, &name, &root );
+
+    if (!do_fsync())
+    {
+        set_error( STATUS_NOT_IMPLEMENTED );
+        return;
+    }
+
+    if (!objattr) return;
+
+    if ((fsync = create_fsync( root, &name, objattr->attributes, req->low,
+                               req->high, req->type, sd )))
+    {
+        if (get_error() == STATUS_OBJECT_NAME_EXISTS)
+            reply->handle = alloc_handle( current->process, fsync, req->access, objattr->attributes );
+        else
+            reply->handle = alloc_handle_no_access_check( current->process, fsync,
+                                                          req->access, objattr->attributes );
+
+        reply->shm_idx = fsync->shm_idx;
+        reply->type = fsync->type;
+        release_object( fsync );
+    }
+
+    if (root) release_object( root );
+}
+
+DECL_HANDLER(open_fsync)
+{
+    struct unicode_str name = get_req_unicode_str();
+
+    reply->handle = open_object( current->process, req->rootdir, req->access,
+                                 &fsync_ops, &name, req->attributes );
+
+    if (reply->handle)
+    {
+        struct fsync *fsync;
+
+        if (!(fsync = (struct fsync *)get_handle_obj( current->process, reply->handle,
+                                                      0, &fsync_ops )))
+            return;
+
+        if (!type_matches( req->type, fsync->type ))
+        {
+            set_error( STATUS_OBJECT_TYPE_MISMATCH );
+            release_object( fsync );
+            return;
+        }
+
+        reply->type = fsync->type;
+        reply->shm_idx = fsync->shm_idx;
+        release_object( fsync );
+    }
+}
+
+/* Retrieve the index of a shm section which will be signaled by the server. */
+DECL_HANDLER(get_fsync_idx)
+{
+    struct object *obj;
+    enum fsync_type type;
+
+    if (!(obj = get_handle_obj( current->process, req->handle, SYNCHRONIZE, NULL )))
+        return;
+
+    if (obj->ops->get_fsync_idx)
+    {
+        reply->shm_idx = obj->ops->get_fsync_idx( obj, &type );
+        reply->type = type;
+    }
+    else
+    {
+        if (debug_level)
+        {
+            fprintf( stderr, "%04x: fsync: can't wait on object: ", current->id );
+            obj->ops->dump( obj, 0 );
+        }
+        set_error( STATUS_NOT_IMPLEMENTED );
+    }
+
+    release_object( obj );
+}
+
+DECL_HANDLER(get_fsync_apc_idx)
+{
+    reply->shm_idx = current->fsync_apc_idx;
+}
diff --git a/server/fsync.h b/server/fsync.h
new file mode 100644
index 00000000000..a91939b7f0a
--- /dev/null
+++ b/server/fsync.h
@@ -0,0 +1,34 @@
+/*
+ * futex-based synchronization objects
+ *
+ * Copyright (C) 2018 Zebediah Figura
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+extern int do_fsync(void);
+extern void fsync_init(void);
+extern unsigned int fsync_alloc_shm( int low, int high );
+extern void fsync_wake_futex( unsigned int shm_idx );
+extern void fsync_clear_futex( unsigned int shm_idx );
+extern void fsync_wake_up( struct object *obj );
+extern void fsync_clear( struct object *obj );
+
+struct fsync;
+
+extern const struct object_ops fsync_ops;
+extern void fsync_set_event( struct fsync *fsync );
+extern void fsync_reset_event( struct fsync *fsync );
+extern void fsync_abandon_mutexes( struct thread *thread );
diff --git a/server/handle.c b/server/handle.c
index cb5628b7e06..ff44446acc9 100644
--- a/server/handle.c
+++ b/server/handle.c
@@ -124,6 +124,7 @@ static const struct object_ops handle_table_ops =
     NULL,                            /* remove_queue */
     NULL,                            /* signaled */
     NULL,                            /* get_esync_fd */
+    NULL,                            /* get_fsync_idx */
     NULL,                            /* satisfied */
     no_signal,                       /* signal */
     no_get_fd,                       /* get_fd */
diff --git a/server/hook.c b/server/hook.c
index 61b5014c442..379f9c074d5 100644
--- a/server/hook.c
+++ b/server/hook.c
@@ -82,6 +82,7 @@ static const struct object_ops hook_table_ops =
     NULL,                         /* remove_queue */
     NULL,                         /* signaled */
     NULL,                         /* get_esync_fd */
+    NULL,                         /* get_fsync_idx */
     NULL,                         /* satisfied */
     no_signal,                    /* signal */
     no_get_fd,                    /* get_fd */
diff --git a/server/mailslot.c b/server/mailslot.c
index 18fef4b0466..b541524c9a4 100644
--- a/server/mailslot.c
+++ b/server/mailslot.c
@@ -79,6 +79,7 @@ static const struct object_ops mailslot_ops =
     remove_queue,              /* remove_queue */
     default_fd_signaled,       /* signaled */
     NULL,                      /* get_esync_fd */
+    NULL,                      /* get_fsync_idx */
     no_satisfied,              /* satisfied */
     no_signal,                 /* signal */
     mailslot_get_fd,           /* get_fd */
@@ -138,6 +139,7 @@ static const struct object_ops mail_writer_ops =
     NULL,                       /* remove_queue */
     NULL,                       /* signaled */
     NULL,                       /* get_esync_fd */
+    NULL,                       /* get_fsync_idx */
     NULL,                       /* satisfied */
     no_signal,                  /* signal */
     mail_writer_get_fd,         /* get_fd */
@@ -202,6 +204,7 @@ static const struct object_ops mailslot_device_ops =
     NULL,                           /* remove_queue */
     NULL,                           /* signaled */
     NULL,                           /* get_esync_fd */
+    NULL,                           /* get_fsync_idx */
     no_satisfied,                   /* satisfied */
     no_signal,                      /* signal */
     no_get_fd,                      /* get_fd */
@@ -233,6 +236,7 @@ static const struct object_ops mailslot_device_file_ops =
     remove_queue,                           /* remove_queue */
     default_fd_signaled,                    /* signaled */
     NULL,                                   /* get_esync_fd */
+    NULL,                                   /* get_fsync_idx */
     no_satisfied,                           /* satisfied */
     no_signal,                              /* signal */
     mailslot_device_file_get_fd,            /* get_fd */
diff --git a/server/main.c b/server/main.c
index 3e02cbb3832..7a09436b637 100644
--- a/server/main.c
+++ b/server/main.c
@@ -37,6 +37,7 @@
 #include "thread.h"
 #include "request.h"
 #include "esync.h"
+#include "fsync.h"
 
 /* command-line options */
 int debug_level = 0;
@@ -141,8 +142,14 @@ int main( int argc, char *argv[] )
     sock_init();
     open_master_socket();
 
+    if (do_fsync())
+        fsync_init();
+
     if (do_esync())
         esync_init();
+ 
+    if (!do_fsync() && !do_esync())
+        fprintf( stderr, "wineserver: using server-side synchronization.\n" );
 
     if (debug_level) fprintf( stderr, "wineserver: starting (pid=%ld)\n", (long) getpid() );
     set_current_time();
diff --git a/server/mapping.c b/server/mapping.c
index 10def3ca694..d55df5145f7 100644
--- a/server/mapping.c
+++ b/server/mapping.c
@@ -69,6 +69,7 @@ static const struct object_ops ranges_ops =
     NULL,                      /* remove_queue */
     NULL,                      /* signaled */
     NULL,                      /* get_esync_fd */
+    NULL,                      /* get_fsync_idx */
     NULL,                      /* satisfied */
     no_signal,                 /* signal */
     no_get_fd,                 /* get_fd */
@@ -106,6 +107,7 @@ static const struct object_ops shared_map_ops =
     NULL,                      /* remove_queue */
     NULL,                      /* signaled */
     NULL,                      /* get_esync_fd */
+    NULL,                      /* get_fsync_idx */
     NULL,                      /* satisfied */
     no_signal,                 /* signal */
     no_get_fd,                 /* get_fd */
@@ -165,6 +167,7 @@ static const struct object_ops mapping_ops =
     NULL,                        /* remove_queue */
     NULL,                        /* signaled */
     NULL,                        /* get_esync_fd */
+    NULL,                        /* get_fsync_idx */
     NULL,                        /* satisfied */
     no_signal,                   /* signal */
     mapping_get_fd,              /* get_fd */
diff --git a/server/mutex.c b/server/mutex.c
index 1235ab4731f..ccdc383f0df 100644
--- a/server/mutex.c
+++ b/server/mutex.c
@@ -62,6 +62,7 @@ static const struct object_ops mutex_ops =
     remove_queue,              /* remove_queue */
     mutex_signaled,            /* signaled */
     NULL,                      /* get_esync_fd */
+    NULL,                      /* get_fsync_idx */
     mutex_satisfied,           /* satisfied */
     mutex_signal,              /* signal */
     no_get_fd,                 /* get_fd */
diff --git a/server/named_pipe.c b/server/named_pipe.c
index e59a5b6c183..d0ea32a24d5 100644
--- a/server/named_pipe.c
+++ b/server/named_pipe.c
@@ -119,6 +119,7 @@ static const struct object_ops named_pipe_ops =
     NULL,                         /* remove_queue */
     NULL,                         /* signaled */
     NULL,                         /* get_esync_fd */
+    NULL,                         /* get_fsync_idx */
     NULL,                         /* satisfied */
     no_signal,                    /* signal */
     no_get_fd,                    /* get_fd */
@@ -164,6 +165,7 @@ static const struct object_ops pipe_server_ops =
     remove_queue,                 /* remove_queue */
     default_fd_signaled,          /* signaled */
     default_fd_get_esync_fd,      /* get_esync_fd */
+    default_fd_get_fsync_idx,     /* get_fsync_idx */
     no_satisfied,                 /* satisfied */
     no_signal,                    /* signal */
     pipe_end_get_fd,              /* get_fd */
@@ -208,6 +210,7 @@ static const struct object_ops pipe_client_ops =
     remove_queue,                 /* remove_queue */
     default_fd_signaled,          /* signaled */
     default_fd_get_esync_fd,      /* get_esync_fd */
+    default_fd_get_fsync_idx,     /* get_fsync_idx */
     no_satisfied,                 /* satisfied */
     no_signal,                    /* signal */
     pipe_end_get_fd,              /* get_fd */
@@ -256,6 +259,7 @@ static const struct object_ops named_pipe_device_ops =
     NULL,                             /* remove_queue */
     NULL,                             /* signaled */
     NULL,                             /* get_esync_fd */
+    NULL,                             /* get_fsync_idx */
     no_satisfied,                     /* satisfied */
     no_signal,                        /* signal */
     no_get_fd,                        /* get_fd */
@@ -288,6 +292,7 @@ static const struct object_ops named_pipe_device_file_ops =
     remove_queue,                            /* remove_queue */
     default_fd_signaled,                     /* signaled */
     NULL,                                    /* get_esync_fd */
+    NULL,                                    /* get_fsync_idx */
     no_satisfied,                            /* satisfied */
     no_signal,                               /* signal */
     named_pipe_device_file_get_fd,           /* get_fd */
diff --git a/server/object.h b/server/object.h
index 5b6bb9cbfe1..4c92b174ef3 100644
--- a/server/object.h
+++ b/server/object.h
@@ -70,6 +70,8 @@ struct object_ops
     int  (*signaled)(struct object *,struct wait_queue_entry *);
     /* return the esync fd for this object */
     int (*get_esync_fd)(struct object *, enum esync_type *type);
+    /* return the fsync shm idx for this object */
+    unsigned int (*get_fsync_idx)(struct object *, enum fsync_type *type);
     /* wait satisfied */
     void (*satisfied)(struct object *,struct wait_queue_entry *);
     /* signal an object */
diff --git a/server/process.c b/server/process.c
index df50955f621..c4f51dcad30 100644
--- a/server/process.c
+++ b/server/process.c
@@ -50,6 +50,7 @@
 #include "user.h"
 #include "security.h"
 #include "esync.h"
+#include "fsync.h"
 
 /* process structure */
 
@@ -70,6 +71,7 @@ static void process_poll_event( struct fd *fd, int event );
 static struct list *process_get_kernel_obj_list( struct object *obj );
 static void process_destroy( struct object *obj );
 static int process_get_esync_fd( struct object *obj, enum esync_type *type );
+static unsigned int process_get_fsync_idx( struct object *obj, enum fsync_type *type );
 static void terminate_process( struct process *process, struct thread *skip, int exit_code );
 
 static const struct object_ops process_ops =
@@ -81,6 +83,7 @@ static const struct object_ops process_ops =
     remove_queue,                /* remove_queue */
     process_signaled,            /* signaled */
     process_get_esync_fd,        /* get_esync_fd */
+    process_get_fsync_idx,       /* get_fsync_idx */
     no_satisfied,                /* satisfied */
     no_signal,                   /* signal */
     no_get_fd,                   /* get_fd */
@@ -133,6 +136,7 @@ static const struct object_ops startup_info_ops =
     remove_queue,                  /* remove_queue */
     startup_info_signaled,         /* signaled */
     NULL,                          /* get_esync_fd */
+    NULL,                          /* get_fsync_idx */
     no_satisfied,                  /* satisfied */
     no_signal,                     /* signal */
     no_get_fd,                     /* get_fd */
@@ -180,6 +184,7 @@ static const struct object_ops job_ops =
     remove_queue,                  /* remove_queue */
     job_signaled,                  /* signaled */
     NULL,                          /* get_esync_fd */
+    NULL,                          /* get_fsync_idx */
     no_satisfied,                  /* satisfied */
     no_signal,                     /* signal */
     no_get_fd,                     /* get_fd */
@@ -547,6 +552,7 @@ struct process *create_process( int fd, struct process *parent, int inherit_all,
     process->rawinput_mouse  = NULL;
     process->rawinput_kbd    = NULL;
     process->esync_fd        = -1;
+    process->fsync_idx       = 0;
     list_init( &process->kernel_object );
     list_init( &process->thread_list );
     list_init( &process->locks );
@@ -603,6 +609,9 @@ struct process *create_process( int fd, struct process *parent, int inherit_all,
     if (!token_assign_label( process->token, security_high_label_sid ))
         goto error;
 
+    if (do_fsync())
+        process->fsync_idx = fsync_alloc_shm( 0, 0 );
+
     if (do_esync())
         process->esync_fd = esync_create_fd( 0, 0 );
 
@@ -685,6 +694,13 @@ static int process_get_esync_fd( struct object *obj, enum esync_type *type )
     return process->esync_fd;
 }
 
+static unsigned int process_get_fsync_idx( struct object *obj, enum fsync_type *type )
+{
+    struct process *process = (struct process *)obj;
+    *type = FSYNC_MANUAL_SERVER;
+    return process->fsync_idx;
+}
+
 static unsigned int process_map_access( struct object *obj, unsigned int access )
 {
     if (access & GENERIC_READ)    access |= STANDARD_RIGHTS_READ | PROCESS_QUERY_INFORMATION | PROCESS_VM_READ;
diff --git a/server/process.h b/server/process.h
index eec69ddbcaf..abb4ed31b48 100644
--- a/server/process.h
+++ b/server/process.h
@@ -99,6 +99,7 @@ struct process
     const struct rawinput_device *rawinput_kbd;   /* rawinput keyboard device, if any */
     struct list          kernel_object;   /* list of kernel object pointers */
     int                  esync_fd;        /* esync file descriptor (signaled on exit) */
+    unsigned int         fsync_idx;
 };
 
 #define CPU_FLAG(cpu) (1 << (cpu))
diff --git a/server/protocol.def b/server/protocol.def
index 2a8662354f6..381bd8d8218 100644
--- a/server/protocol.def
+++ b/server/protocol.def
@@ -3766,3 +3766,57 @@ enum esync_type
 /* Retrieve the fd to wait on for user APCs. */
 @REQ(get_esync_apc_fd)
 @END
+
+enum fsync_type
+{
+    FSYNC_SEMAPHORE = 1,
+    FSYNC_AUTO_EVENT,
+    FSYNC_MANUAL_EVENT,
+    FSYNC_MUTEX,
+    FSYNC_AUTO_SERVER,
+    FSYNC_MANUAL_SERVER,
+    FSYNC_QUEUE,
+};
+
+/* Create a new futex-based synchronization object */
+@REQ(create_fsync)
+    unsigned int access;        /* wanted access rights */
+    int low;                    /* initial value of low word */
+    int high;                   /* initial value of high word */
+    int type;                   /* type of fsync object */
+    VARARG(objattr,object_attributes); /* object attributes */
+@REPLY
+    obj_handle_t handle;        /* handle to the object */
+    int type;                   /* type of fsync object */
+    unsigned int shm_idx;       /* this object's index into the shm section */
+@END
+
+/* Open an fsync object */
+@REQ(open_fsync)
+    unsigned int access;        /* wanted access rights */
+    unsigned int attributes;    /* object attributes */
+    obj_handle_t rootdir;       /* root directory */
+    int          type;          /* type of fsync object */
+    VARARG(name,unicode_str);   /* object name */
+@REPLY
+    obj_handle_t handle;        /* handle to the event */
+    int          type;          /* type of fsync object */
+    unsigned int shm_idx;       /* this object's index into the shm section */
+@END
+
+/* Retrieve the shm index for an object. */
+@REQ(get_fsync_idx)
+    obj_handle_t handle;        /* handle to the object */
+@REPLY
+    int          type;
+    unsigned int shm_idx;
+@END
+
+@REQ(fsync_msgwait)
+    int          in_msgwait;    /* are we in a message wait? */
+@END
+
+@REQ(get_fsync_apc_idx)
+@REPLY
+    unsigned int shm_idx;
+@END
diff --git a/server/queue.c b/server/queue.c
index a78748b96ca..dccf43197cf 100644
--- a/server/queue.c
+++ b/server/queue.c
@@ -44,6 +44,7 @@
 #include "request.h"
 #include "user.h"
 #include "esync.h"
+#include "fsync.h"
 
 #define WM_NCMOUSEFIRST WM_NCMOUSEMOVE
 #define WM_NCMOUSELAST  (WM_NCMOUSEFIRST+(WM_MOUSELAST-WM_MOUSEFIRST))
@@ -147,6 +148,8 @@ struct msg_queue
     unsigned int           ignore_post_msg; /* ignore post messages newer than this unique id */
     int                    esync_fd;        /* esync file descriptor (signalled on message) */
     int                    esync_in_msgwait; /* our thread is currently waiting on us */
+    unsigned int           fsync_idx;
+    int                    fsync_in_msgwait; /* our thread is currently waiting on us */
 };
 
 struct hotkey
@@ -164,6 +167,7 @@ static int msg_queue_add_queue( struct object *obj, struct wait_queue_entry *ent
 static void msg_queue_remove_queue( struct object *obj, struct wait_queue_entry *entry );
 static int msg_queue_signaled( struct object *obj, struct wait_queue_entry *entry );
 static int msg_queue_get_esync_fd( struct object *obj, enum esync_type *type );
+static unsigned int msg_queue_get_fsync_idx( struct object *obj, enum fsync_type *type );
 static void msg_queue_satisfied( struct object *obj, struct wait_queue_entry *entry );
 static void msg_queue_destroy( struct object *obj );
 static void msg_queue_poll_event( struct fd *fd, int event );
@@ -180,6 +184,7 @@ static const struct object_ops msg_queue_ops =
     msg_queue_remove_queue,    /* remove_queue */
     msg_queue_signaled,        /* signaled */
     msg_queue_get_esync_fd,    /* get_esync_fd */
+    msg_queue_get_fsync_idx,   /* get_fsync_idx */
     msg_queue_satisfied,       /* satisfied */
     no_signal,                 /* signal */
     no_get_fd,                 /* get_fd */
@@ -218,6 +223,7 @@ static const struct object_ops thread_input_ops =
     NULL,                         /* remove_queue */
     NULL,                         /* signaled */
     NULL,                         /* get_esync_fd */
+    NULL,                         /* get_fsync_idx */
     NULL,                         /* satisfied */
     no_signal,                    /* signal */
     no_get_fd,                    /* get_fd */
@@ -321,12 +327,17 @@ static struct msg_queue *create_msg_queue( struct thread *thread, struct thread_
         queue->ignore_post_msg = 0;
         queue->esync_fd        = -1;
         queue->esync_in_msgwait = 0;
+        queue->fsync_idx       = 0;
+        queue->fsync_in_msgwait = 0;
         list_init( &queue->send_result );
         list_init( &queue->callback_result );
         list_init( &queue->pending_timers );
         list_init( &queue->expired_timers );
         for (i = 0; i < NB_MSG_KINDS; i++) list_init( &queue->msg_list[i] );
  
+        if (do_fsync())
+            queue->fsync_idx = fsync_alloc_shm( 0, 0 );
+ 
         if (do_esync())
             queue->esync_fd = esync_create_fd( 0, 0 );
 
@@ -509,6 +520,9 @@ static inline void clear_queue_bits( struct msg_queue *queue, unsigned int bits
     queue->wake_bits &= ~bits;
     queue->changed_bits &= ~bits;
 
+    if (do_fsync() && !is_signaled( queue ))
+        fsync_clear( &queue->obj );
+
     if (do_esync() && !is_signaled( queue ))
         esync_clear( queue->esync_fd );
 }
@@ -970,6 +984,9 @@ static int is_queue_hung( struct msg_queue *queue )
             return 0;  /* thread is waiting on queue -> not hung */
     }
 
+    if (do_fsync() && queue->fsync_in_msgwait)
+        return 0;   /* thread is waiting on queue in absentia -> not hung */
+
     if (do_esync() && queue->esync_in_msgwait)
         return 0;   /* thread is waiting on queue in absentia -> not hung */
 
@@ -1035,6 +1052,13 @@ static int msg_queue_get_esync_fd( struct object *obj, enum esync_type *type )
     return queue->esync_fd;
 }
 
+static unsigned int msg_queue_get_fsync_idx( struct object *obj, enum fsync_type *type )
+{
+    struct msg_queue *queue = (struct msg_queue *)obj;
+    *type = FSYNC_QUEUE;
+    return queue->fsync_idx;
+}
+
 static void msg_queue_satisfied( struct object *obj, struct wait_queue_entry *entry )
 {
     struct msg_queue *queue = (struct msg_queue *)obj;
@@ -2517,6 +2541,9 @@ DECL_HANDLER(get_queue_status)
         reply->changed_bits = queue->changed_bits;
         queue->changed_bits &= ~req->clear_bits;
 
+        if (do_fsync() && !is_signaled( queue ))
+            fsync_clear( &queue->obj );
+
         if (do_esync() && !is_signaled( queue ))
             esync_clear( queue->esync_fd );
     }
@@ -3536,3 +3563,18 @@ DECL_HANDLER(esync_msgwait)
     if (queue->fd)
         set_fd_events( queue->fd, req->in_msgwait ? POLLIN : 0 );
 }
+
+DECL_HANDLER(fsync_msgwait)
+{
+    struct msg_queue *queue = get_current_queue();
+
+    if (!queue) return;
+    queue->fsync_in_msgwait = req->in_msgwait;
+
+    if (current->process->idle_event && !(queue->wake_mask & QS_SMRESULT))
+        set_event( current->process->idle_event );
+
+    /* and start/stop waiting on the driver */
+    if (queue->fd)
+        set_fd_events( queue->fd, req->in_msgwait ? POLLIN : 0 );
+}
diff --git a/server/registry.c b/server/registry.c
index 996bff5ef6d..50b600b4853 100644
--- a/server/registry.c
+++ b/server/registry.c
@@ -168,6 +168,7 @@ static const struct object_ops key_ops =
     NULL,                    /* remove_queue */
     NULL,                    /* signaled */
     NULL,                    /* get_esync_fd */
+    NULL,                    /* get_fsync_idx */
     NULL,                    /* satisfied */
     no_signal,               /* signal */
     no_get_fd,               /* get_fd */
diff --git a/server/request.c b/server/request.c
index 20b0ec309f3..9fd08139375 100644
--- a/server/request.c
+++ b/server/request.c
@@ -97,6 +97,7 @@ static const struct object_ops master_socket_ops =
     NULL,                          /* remove_queue */
     NULL,                          /* signaled */
     NULL,                          /* get_esync_fd */
+    NULL,                          /* get_fsync_idx */
     NULL,                          /* satisfied */
     no_signal,                     /* signal */
     no_get_fd,                     /* get_fd */
diff --git a/server/semaphore.c b/server/semaphore.c
index d7d3a24e48f..604721d0d5f 100644
--- a/server/semaphore.c
+++ b/server/semaphore.c
@@ -59,6 +59,7 @@ static const struct object_ops semaphore_ops =
     remove_queue,                  /* remove_queue */
     semaphore_signaled,            /* signaled */
     NULL,                          /* get_esync_fd */
+    NULL,                          /* get_fsync_idx */
     semaphore_satisfied,           /* satisfied */
     semaphore_signal,              /* signal */
     no_get_fd,                     /* get_fd */
diff --git a/server/serial.c b/server/serial.c
index a50ace9903f..78d33460892 100644
--- a/server/serial.c
+++ b/server/serial.c
@@ -93,6 +93,7 @@ static const struct object_ops serial_ops =
     remove_queue,                 /* remove_queue */
     default_fd_signaled,          /* signaled */
     NULL,                         /* get_esync_fd */
+    NULL,                         /* get_fsync_idx */
     no_satisfied,                 /* satisfied */
     no_signal,                    /* signal */
     serial_get_fd,                /* get_fd */
diff --git a/server/signal.c b/server/signal.c
index b6d6dcfc4b6..f5ac61b6975 100644
--- a/server/signal.c
+++ b/server/signal.c
@@ -68,6 +68,7 @@ static const struct object_ops handler_ops =
     NULL,                     /* remove_queue */
     NULL,                     /* signaled */
     NULL,                     /* get_esync_fd */
+    NULL,                     /* get_fsync_idx */
     NULL,                     /* satisfied */
     no_signal,                /* signal */
     no_get_fd,                /* get_fd */
diff --git a/server/sock.c b/server/sock.c
index c2dfa8fb8ce..080efc98942 100644
--- a/server/sock.c
+++ b/server/sock.c
@@ -173,6 +173,7 @@ static const struct object_ops sock_ops =
     remove_queue,                 /* remove_queue */
     sock_signaled,                /* signaled */
     NULL,                         /* get_esync_fd */
+    NULL,                         /* get_fsync_idx */
     no_satisfied,                 /* satisfied */
     no_signal,                    /* signal */
     sock_get_fd,                  /* get_fd */
@@ -1175,6 +1176,7 @@ static const struct object_ops ifchange_ops =
     NULL,                    /* remove_queue */
     NULL,                    /* signaled */
     NULL,                    /* get_esync_fd */
+    NULL,                    /* get_fsync_idx */
     no_satisfied,            /* satisfied */
     no_signal,               /* signal */
     ifchange_get_fd,         /* get_fd */
@@ -1396,6 +1398,7 @@ static const struct object_ops socket_device_ops =
     NULL,                       /* remove_queue */
     NULL,                       /* signaled */
     NULL,                       /* get_esync_fd */
+    NULL,                       /* get_fsync_idx */
     no_satisfied,               /* satisfied */
     no_signal,                  /* signal */
     no_get_fd,                  /* get_fd */
diff --git a/server/symlink.c b/server/symlink.c
index 07f3c924f25..0e3e9ee9864 100644
--- a/server/symlink.c
+++ b/server/symlink.c
@@ -61,6 +61,7 @@ static const struct object_ops symlink_ops =
     NULL,                         /* remove_queue */
     NULL,                         /* signaled */
     NULL,                         /* get_esync_fd */
+    NULL,                         /* get_fsync_idx */
     NULL,                         /* satisfied */
     no_signal,                    /* signal */
     no_get_fd,                    /* get_fd */
diff --git a/server/thread.c b/server/thread.c
index 1a245c58396..1fb3603f2a7 100644
--- a/server/thread.c
+++ b/server/thread.c
@@ -52,6 +52,7 @@
 #include "user.h"
 #include "security.h"
 #include "esync.h"
+#include "fsync.h"
 
 
 #ifdef __i386__
@@ -112,6 +113,7 @@ static const struct object_ops thread_apc_ops =
     remove_queue,               /* remove_queue */
     thread_apc_signaled,        /* signaled */
     NULL,                       /* get_esync_fd */
+    NULL,                       /* get_fsync_idx */
     no_satisfied,               /* satisfied */
     no_signal,                  /* signal */
     no_get_fd,                  /* get_fd */
@@ -150,6 +152,7 @@ static const struct object_ops context_ops =
     remove_queue,               /* remove_queue */
     context_signaled,           /* signaled */
     NULL,                       /* get_esync_fd */
+    NULL,                       /* get_fsync_idx */
     no_satisfied,               /* satisfied */
     no_signal,                  /* signal */
     no_get_fd,                  /* get_fd */
@@ -173,6 +176,7 @@ static void dump_thread( struct object *obj, int verbose );
 static struct object_type *thread_get_type( struct object *obj );
 static int thread_signaled( struct object *obj, struct wait_queue_entry *entry );
 static int thread_get_esync_fd( struct object *obj, enum esync_type *type );
+static unsigned int thread_get_fsync_idx( struct object *obj, enum fsync_type *type );
 static unsigned int thread_map_access( struct object *obj, unsigned int access );
 static void thread_poll_event( struct fd *fd, int event );
 static struct list *thread_get_kernel_obj_list( struct object *obj );
@@ -187,6 +191,7 @@ static const struct object_ops thread_ops =
     remove_queue,               /* remove_queue */
     thread_signaled,            /* signaled */
     thread_get_esync_fd,        /* get_esync_fd */
+    thread_get_fsync_idx,       /* get_fsync_idx */
     no_satisfied,               /* satisfied */
     no_signal,                  /* signal */
     no_get_fd,                  /* get_fd */
@@ -228,6 +233,7 @@ static inline void init_thread_structure( struct thread *thread )
     thread->entry_point     = 0;
     thread->esync_fd        = -1;
     thread->esync_apc_fd    = -1;
+    thread->fsync_idx       = 0;
     thread->debug_ctx       = NULL;
     thread->system_regs     = 0;
     thread->queue           = NULL;
@@ -364,6 +370,12 @@ struct thread *create_thread( int fd, struct process *process, const struct secu
         return NULL;
     }
 
+    if (do_fsync())
+    {
+        thread->fsync_idx = fsync_alloc_shm( 0, 0 );
+        thread->fsync_apc_idx = fsync_alloc_shm( 0, 0 );
+    }
+
     if (do_esync())
     {
         thread->esync_fd = esync_create_fd( 0, 0 );
@@ -484,6 +496,13 @@ static int thread_get_esync_fd( struct object *obj, enum esync_type *type )
     return thread->esync_fd;
 }
 
+static unsigned int thread_get_fsync_idx( struct object *obj, enum fsync_type *type )
+{
+    struct thread *thread = (struct thread *)obj;
+    *type = FSYNC_MANUAL_SERVER;
+    return thread->fsync_idx;
+}
+
 static unsigned int thread_map_access( struct object *obj, unsigned int access )
 {
     if (access & GENERIC_READ)    access |= STANDARD_RIGHTS_READ | THREAD_QUERY_INFORMATION | THREAD_GET_CONTEXT;
@@ -533,6 +552,7 @@ static struct thread_apc *create_apc( struct object *owner, const apc_call_t *ca
         apc->result.type = APC_NONE;
         if (owner) grab_object( owner );
     }
+
     return apc;
 }
 
@@ -1068,6 +1088,9 @@ void wake_up( struct object *obj, int max )
     struct list *ptr;
     int ret;
 
+    if (do_fsync())
+        fsync_wake_up( obj );
+
     if (do_esync())
         esync_wake_up( obj );
 
@@ -1158,6 +1181,9 @@ static int queue_apc( struct process *process, struct thread *thread, struct thr
     {
         wake_thread( thread );
 
+        if (do_fsync() && queue == &thread->user_apc)
+            fsync_wake_futex( thread->fsync_apc_idx );
+
         if (do_esync() && queue == &thread->user_apc)
             esync_wake_fd( thread->esync_apc_fd );
     }
@@ -1208,6 +1234,9 @@ static struct thread_apc *thread_dequeue_apc( struct thread *thread, int system
         list_remove( ptr );
     }
 
+    if (do_fsync() && list_empty( &thread->system_apc ) && list_empty( &thread->user_apc ))
+        fsync_clear_futex( thread->fsync_apc_idx );
+
     if (do_esync() && list_empty( &thread->system_apc ) && list_empty( &thread->user_apc ))
         esync_clear( thread->esync_apc_fd );
 
@@ -1327,6 +1356,8 @@ void kill_thread( struct thread *thread, int violent_death )
     kill_console_processes( thread, 0 );
     debug_exit_thread( thread );
     abandon_mutexes( thread );
+    if (do_fsync())
+        fsync_abandon_mutexes( thread );
     if (do_esync())
         esync_abandon_mutexes( thread );
     if (violent_death)
diff --git a/server/thread.h b/server/thread.h
index 0f6108b684a..53627631343 100644
--- a/server/thread.h
+++ b/server/thread.h
@@ -56,6 +56,8 @@ struct thread
     struct list            mutex_list;    /* list of currently owned mutexes */
     int                    esync_fd;      /* esync file descriptor (signalled on exit) */
     int                    esync_apc_fd;  /* esync apc fd (signalled when APCs are present) */
+    unsigned int           fsync_idx;
+    unsigned int           fsync_apc_idx;
     struct debug_ctx      *debug_ctx;     /* debugger context if this thread is a debugger */
     unsigned int           system_regs;   /* which system regs have been set */
     struct msg_queue      *queue;         /* message queue */
diff --git a/server/timer.c b/server/timer.c
index dcbc9e2ece5..9d9d7b8b40c 100644
--- a/server/timer.c
+++ b/server/timer.c
@@ -37,6 +37,7 @@
 #include "handle.h"
 #include "request.h"
 #include "esync.h"
+#include "fsync.h"
 
 struct timer
 {
@@ -50,12 +51,14 @@ struct timer
     client_ptr_t         callback;  /* callback APC function */
     client_ptr_t         arg;       /* callback argument */
     int                  esync_fd;  /* esync file descriptor */
+    unsigned int         fsync_idx; /* fsync shm index */
 };
 
 static void timer_dump( struct object *obj, int verbose );
 static struct object_type *timer_get_type( struct object *obj );
 static int timer_signaled( struct object *obj, struct wait_queue_entry *entry );
 static int timer_get_esync_fd( struct object *obj, enum esync_type *type );
+static unsigned int timer_get_fsync_idx( struct object *obj, enum fsync_type *type );
 static void timer_satisfied( struct object *obj, struct wait_queue_entry *entry );
 static unsigned int timer_map_access( struct object *obj, unsigned int access );
 static void timer_destroy( struct object *obj );
@@ -69,6 +72,7 @@ static const struct object_ops timer_ops =
     remove_queue,              /* remove_queue */
     timer_signaled,            /* signaled */
     timer_get_esync_fd,        /* get_esync_fd */
+    timer_get_fsync_idx,       /* get_fsync_idx */
     timer_satisfied,           /* satisfied */
     no_signal,                 /* signal */
     no_get_fd,                 /* get_fd */
@@ -105,6 +109,9 @@ static struct timer *create_timer( struct object *root, const struct unicode_str
             timer->thread   = NULL;
             timer->esync_fd = -1;
 
+            if (do_fsync())
+                timer->fsync_idx = fsync_alloc_shm( 0, 0 );
+
             if (do_esync())
                 timer->esync_fd = esync_create_fd( 0, 0 );
         }
@@ -181,6 +188,9 @@ static int set_timer( struct timer *timer, timeout_t expire, unsigned int period
         period = 0;  /* period doesn't make any sense for a manual timer */
         timer->signaled = 0;
 
+        if (do_fsync())
+            fsync_clear( &timer->obj );
+
         if (do_esync())
             esync_clear( timer->esync_fd );
     }
@@ -223,6 +233,13 @@ static int timer_get_esync_fd( struct object *obj, enum esync_type *type )
     return timer->esync_fd;
 }
 
+static unsigned int timer_get_fsync_idx( struct object *obj, enum fsync_type *type )
+{
+    struct timer *timer = (struct timer *)obj;
+    *type = timer->manual ? FSYNC_MANUAL_SERVER : FSYNC_AUTO_SERVER;
+    return timer->fsync_idx;
+}
+
 static void timer_satisfied( struct object *obj, struct wait_queue_entry *entry )
 {
     struct timer *timer = (struct timer *)obj;
diff --git a/server/token.c b/server/token.c
index 0f128728b0f..5a80b6fd50e 100644
--- a/server/token.c
+++ b/server/token.c
@@ -148,6 +148,7 @@ static const struct object_ops token_ops =
     NULL,                      /* remove_queue */
     NULL,                      /* signaled */
     NULL,                      /* get_esync_fd */
+    NULL,                      /* get_fsync_idx */
     NULL,                      /* satisfied */
     no_signal,                 /* signal */
     no_get_fd,                 /* get_fd */
diff --git a/server/winstation.c b/server/winstation.c
index 1a031248a7c..388b116bc67 100644
--- a/server/winstation.c
+++ b/server/winstation.c
@@ -65,6 +65,7 @@ static const struct object_ops winstation_ops =
     NULL,                         /* remove_queue */
     NULL,                         /* signaled */
     NULL,                         /* get_esync_fd */
+    NULL,                         /* get_fsync_idx */
     NULL,                         /* satisfied */
     no_signal,                    /* signal */
     no_get_fd,                    /* get_fd */
@@ -91,6 +92,7 @@ static const struct object_ops desktop_ops =
     NULL,                         /* remove_queue */
     NULL,                         /* signaled */
     NULL,                         /* get_esync_fd */
+    NULL,                         /* get_fsync_idx */
     NULL,                         /* satisfied */
     no_signal,                    /* signal */
     no_get_fd,                    /* get_fd */