--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/os/bsd/gc/z/zBackingFile_bsd.cpp Tue Nov 12 09:27:21 2019 +0000
@@ -0,0 +1,183 @@
+/*
+ * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+#include "precompiled.hpp"
+#include "gc/z/zBackingFile_bsd.hpp"
+#include "gc/z/zErrno.hpp"
+#include "gc/z/zGlobals.hpp"
+#include "gc/z/zLargePages.inline.hpp"
+#include "gc/z/zPhysicalMemory.inline.hpp"
+#include "logging/log.hpp"
+#include "runtime/globals.hpp"
+#include "runtime/os.hpp"
+#include "utilities/align.hpp"
+#include "utilities/debug.hpp"
+
+#include <mach/mach.h>
+#include <mach/mach_vm.h>
+#include <sys/mman.h>
+#include <sys/types.h>
+
+static int vm_flags_superpage() {
+ if (!ZLargePages::is_explicit()) {
+ return 0;
+ }
+
+ const int page_size_in_megabytes = ZGranuleSize >> 20;
+ return page_size_in_megabytes << VM_FLAGS_SUPERPAGE_SHIFT;
+}
+
+static ZErrno mremap(uintptr_t from_addr, uintptr_t to_addr, size_t size) {
+ mach_vm_address_t remap_addr = to_addr;
+ vm_prot_t remap_cur_prot;
+ vm_prot_t remap_max_prot;
+
+ // Remap memory to an additional location
+ const kern_return_t res = mach_vm_remap(mach_task_self(),
+ &remap_addr,
+ size,
+ 0 /* mask */,
+ VM_FLAGS_FIXED | VM_FLAGS_OVERWRITE | vm_flags_superpage(),
+ mach_task_self(),
+ from_addr,
+ FALSE /* copy */,
+ &remap_cur_prot,
+ &remap_max_prot,
+ VM_INHERIT_COPY);
+
+ return (res == KERN_SUCCESS) ? ZErrno(0) : ZErrno(EINVAL);
+}
+
+ZBackingFile::ZBackingFile() :
+ _base(0),
+ _size(0),
+ _initialized(false) {
+
+ // Reserve address space for virtual backing file
+ _base = (uintptr_t)os::reserve_memory(MaxHeapSize);
+ if (_base == 0) {
+ // Failed
+ log_error(gc)("Failed to reserve address space for virtual backing file");
+ return;
+ }
+
+ // Successfully initialized
+ _initialized = true;
+}
+
+bool ZBackingFile::is_initialized() const {
+ return _initialized;
+}
+
+size_t ZBackingFile::size() const {
+ return _size;
+}
+
+bool ZBackingFile::commit_inner(size_t offset, size_t length) {
+ assert(is_aligned(offset, os::vm_page_size()), "Invalid offset");
+ assert(is_aligned(length, os::vm_page_size()), "Invalid length");
+
+ log_trace(gc, heap)("Committing memory: " SIZE_FORMAT "M-" SIZE_FORMAT "M (" SIZE_FORMAT "M)",
+ offset / M, (offset + length) / M, length / M);
+
+ const uintptr_t addr = _base + offset;
+ const void* const res = mmap((void*)addr, length, PROT_READ | PROT_WRITE, MAP_FIXED | MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+ if (res == MAP_FAILED) {
+ ZErrno err;
+ log_error(gc)("Failed to commit memory (%s)", err.to_string());
+ return false;
+ }
+
+ const size_t end = offset + length;
+ if (end > _size) {
+ // Record new virtual file size
+ _size = end;
+ }
+
+ // Success
+ return true;
+}
+
+size_t ZBackingFile::commit(size_t offset, size_t length) {
+ // Try to commit the whole region
+ if (commit_inner(offset, length)) {
+ // Success
+ return length;
+ }
+
+ // Failed, try to commit as much as possible
+ size_t start = offset;
+ size_t end = offset + length;
+
+ for (;;) {
+ length = align_down((end - start) / 2, ZGranuleSize);
+ if (length == 0) {
+ // Done, don't commit more
+ return start - offset;
+ }
+
+ if (commit_inner(start, length)) {
+ // Success, try commit more
+ start += length;
+ } else {
+ // Failed, try commit less
+ end -= length;
+ }
+ }
+}
+
+size_t ZBackingFile::uncommit(size_t offset, size_t length) {
+ assert(is_aligned(offset, os::vm_page_size()), "Invalid offset");
+ assert(is_aligned(length, os::vm_page_size()), "Invalid length");
+
+ log_trace(gc, heap)("Uncommitting memory: " SIZE_FORMAT "M-" SIZE_FORMAT "M (" SIZE_FORMAT "M)",
+ offset / M, (offset + length) / M, length / M);
+
+ const uintptr_t start = _base + offset;
+ const void* const res = mmap((void*)start, length, PROT_NONE, MAP_FIXED | MAP_ANONYMOUS | MAP_PRIVATE | MAP_NORESERVE, -1, 0);
+ if (res == MAP_FAILED) {
+ ZErrno err;
+ log_error(gc)("Failed to uncommit memory (%s)", err.to_string());
+ return 0;
+ }
+
+ return length;
+}
+
+void ZBackingFile::map(uintptr_t addr, size_t size, uintptr_t offset) const {
+ const ZErrno err = mremap(_base + offset, addr, size);
+ if (err) {
+ fatal("Failed to remap memory (%s)", err.to_string());
+ }
+}
+
+void ZBackingFile::unmap(uintptr_t addr, size_t size) const {
+ // Note that we must keep the address space reservation intact and just detach
+ // the backing memory. For this reason we map a new anonymous, non-accessible
+ // and non-reserved page over the mapping instead of actually unmapping.
+ const void* const res = mmap((void*)addr, size, PROT_NONE, MAP_FIXED | MAP_ANONYMOUS | MAP_PRIVATE | MAP_NORESERVE, -1, 0);
+ if (res == MAP_FAILED) {
+ ZErrno err;
+ fatal("Failed to map memory (%s)", err.to_string());
+ }
+}