jdk8-mips64-public/hotspot: comparison src/share/vm/memory/filemap.cpp

--1:000000000000
+:f90c822e73f8
+/*
+* Copyright (c) 2003, 2014, 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 "classfile/classLoader.hpp"
+#include "classfile/symbolTable.hpp"
+#include "classfile/altHashing.hpp"
+#include "memory/filemap.hpp"
+#include "runtime/arguments.hpp"
+#include "runtime/java.hpp"
+#include "runtime/os.hpp"
+#include "services/memTracker.hpp"
+#include "utilities/defaultStream.hpp"
+# include <sys/stat.h>
+# include <errno.h>
+#ifndef O_BINARY       // if defined (Win32) use binary files.
+#define O_BINARY 0     // otherwise do nothing.
+#endif
+PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
+extern address JVM_FunctionAtStart();
+extern address JVM_FunctionAtEnd();
+// Complain and stop. All error conditions occurring during the writing of
+// an archive file should stop the process.  Unrecoverable errors during
+// the reading of the archive file should stop the process.
+static void fail(const char *msg, va_list ap) {
+// This occurs very early during initialization: tty is not initialized.
+jio_fprintf(defaultStream::error_stream(),
+"An error has occurred while processing the"
+" shared archive file.\n");
+jio_vfprintf(defaultStream::error_stream(), msg, ap);
+jio_fprintf(defaultStream::error_stream(), "\n");
+// Do not change the text of the below message because some tests check for it.
+vm_exit_during_initialization("Unable to use shared archive.", NULL);
+}
+void FileMapInfo::fail_stop(const char *msg, ...) {
+va_list ap;
+va_start(ap, msg);
+fail(msg, ap);        // Never returns.
+va_end(ap);           // for completeness.
+}
+// Complain and continue.  Recoverable errors during the reading of the
+// archive file may continue (with sharing disabled).
+//
+// If we continue, then disable shared spaces and close the file.
+void FileMapInfo::fail_continue(const char *msg, ...) {
+va_list ap;
+va_start(ap, msg);
+if (RequireSharedSpaces) {
+fail(msg, ap);
+}
+va_end(ap);
+UseSharedSpaces = false;
+close();
+}
+// Fill in the fileMapInfo structure with data about this VM instance.
+// This method copies the vm version info into header_version.  If the version is too
+// long then a truncated version, which has a hash code appended to it, is copied.
+//
+// Using a template enables this method to verify that header_version is an array of
+// length JVM_IDENT_MAX.  This ensures that the code that writes to the CDS file and
+// the code that reads the CDS file will both use the same size buffer.  Hence, will
+// use identical truncation.  This is necessary for matching of truncated versions.
+template <int N> static void get_header_version(char (&header_version) [N]) {
+assert(N == JVM_IDENT_MAX, "Bad header_version size");
+const char *vm_version = VM_Version::internal_vm_info_string();
+const int version_len = (int)strlen(vm_version);
+if (version_len < (JVM_IDENT_MAX-1)) {
+strcpy(header_version, vm_version);
+} else {
+// Get the hash value.  Use a static seed because the hash needs to return the same
+// value over multiple jvm invocations.
+unsigned int hash = AltHashing::murmur3_32(8191, (const jbyte*)vm_version, version_len);
+// Truncate the ident, saving room for the 8 hex character hash value.
+strncpy(header_version, vm_version, JVM_IDENT_MAX-9);
+// Append the hash code as eight hex digits.
+sprintf(&header_version[JVM_IDENT_MAX-9], "%08x", hash);
+header_version[JVM_IDENT_MAX-1] = 0;  // Null terminate.
+}
+}
+void FileMapInfo::populate_header(size_t alignment) {
+_header._magic = 0xf00baba2;
+_header._version = _current_version;
+_header._alignment = alignment;
+_header._obj_alignment = ObjectAlignmentInBytes;
+// The following fields are for sanity checks for whether this archive
+// will function correctly with this JVM and the bootclasspath it's
+// invoked with.
+// JVM version string ... changes on each build.
+get_header_version(_header._jvm_ident);
+// Build checks on classpath and jar files
+_header._num_jars = 0;
+ClassPathEntry *cpe = ClassLoader::classpath_entry(0);
+for ( ; cpe != NULL; cpe = cpe->next()) {
+if (cpe->is_jar_file()) {
+if (_header._num_jars >= JVM_SHARED_JARS_MAX) {
+fail_stop("Too many jar files to share.", NULL);
+}
+// Jar file - record timestamp and file size.
+struct stat st;
+const char *path = cpe->name();
+if (os::stat(path, &st) != 0) {
+// If we can't access a jar file in the boot path, then we can't
+// make assumptions about where classes get loaded from.
+fail_stop("Unable to open jar file %s.", path);
+}
+_header._jar[_header._num_jars]._timestamp = st.st_mtime;
+_header._jar[_header._num_jars]._filesize = st.st_size;
+_header._num_jars++;
+} else {
+// If directories appear in boot classpath, they must be empty to
+// avoid having to verify each individual class file.
+const char* name = ((ClassPathDirEntry*)cpe)->name();
+if (!os::dir_is_empty(name)) {
+fail_stop("Boot classpath directory %s is not empty.", name);
+}
+}
+}
+}
+// Read the FileMapInfo information from the file.
+bool FileMapInfo::init_from_file(int fd) {
+size_t n = read(fd, &_header, sizeof(struct FileMapHeader));
+if (n != sizeof(struct FileMapHeader)) {
+fail_continue("Unable to read the file header.");
+return false;
+}
+if (_header._version != current_version()) {
+fail_continue("The shared archive file has the wrong version.");
+return false;
+}
+size_t len = lseek(fd, 0, SEEK_END);
+struct FileMapInfo::FileMapHeader::space_info* si =
+&_header._space[MetaspaceShared::mc];
+if (si->_file_offset >= len || len - si->_file_offset < si->_used) {
+fail_continue("The shared archive file has been truncated.");
+return false;
+}
+_file_offset = n;
+return true;
+}
+// Read the FileMapInfo information from the file.
+bool FileMapInfo::open_for_read() {
+_full_path = Arguments::GetSharedArchivePath();
+int fd = open(_full_path, O_RDONLY | O_BINARY, 0);
+if (fd < 0) {
+if (errno == ENOENT) {
+// Not locating the shared archive is ok.
+fail_continue("Specified shared archive not found.");
+} else {
+fail_continue("Failed to open shared archive file (%s).",
+strerror(errno));
+}
+return false;
+}
+_fd = fd;
+_file_open = true;
+return true;
+}
+// Write the FileMapInfo information to the file.
+void FileMapInfo::open_for_write() {
+_full_path = Arguments::GetSharedArchivePath();
+if (PrintSharedSpaces) {
+tty->print_cr("Dumping shared data to file: ");
+tty->print_cr("   %s", _full_path);
+}
+#ifdef _WINDOWS  // On Windows, need WRITE permission to remove the file.
+chmod(_full_path, _S_IREAD | _S_IWRITE);
+#endif
+// Use remove() to delete the existing file because, on Unix, this will
+// allow processes that have it open continued access to the file.
+remove(_full_path);
+int fd = open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0444);
+if (fd < 0) {
+fail_stop("Unable to create shared archive file %s.", _full_path);
+}
+_fd = fd;
+_file_offset = 0;
+_file_open = true;
+}
+// Write the header to the file, seek to the next allocation boundary.
+void FileMapInfo::write_header() {
+write_bytes_aligned(&_header, sizeof(FileMapHeader));
+}
+// Dump shared spaces to file.
+void FileMapInfo::write_space(int i, Metaspace* space, bool read_only) {
+align_file_position();
+size_t used = space->used_bytes_slow(Metaspace::NonClassType);
+size_t capacity = space->capacity_bytes_slow(Metaspace::NonClassType);
+struct FileMapInfo::FileMapHeader::space_info* si = &_header._space[i];
+write_region(i, (char*)space->bottom(), used, capacity, read_only, false);
+}
+// Dump region to file.
+void FileMapInfo::write_region(int region, char* base, size_t size,
+size_t capacity, bool read_only,
+bool allow_exec) {
+struct FileMapInfo::FileMapHeader::space_info* si = &_header._space[region];
+if (_file_open) {
+guarantee(si->_file_offset == _file_offset, "file offset mismatch.");
+if (PrintSharedSpaces) {
+tty->print_cr("Shared file region %d: 0x%6x bytes, addr " INTPTR_FORMAT
+" file offset 0x%6x", region, size, base, _file_offset);
+}
+} else {
+si->_file_offset = _file_offset;
+}
+si->_base = base;
+si->_used = size;
+si->_capacity = capacity;
+si->_read_only = read_only;
+si->_allow_exec = allow_exec;
+si->_crc = ClassLoader::crc32(0, base, (jint)size);
+write_bytes_aligned(base, (int)size);
+}
+// Dump bytes to file -- at the current file position.
+void FileMapInfo::write_bytes(const void* buffer, int nbytes) {
+if (_file_open) {
+int n = ::write(_fd, buffer, nbytes);
+if (n != nbytes) {
+// It is dangerous to leave the corrupted shared archive file around,
+// close and remove the file. See bug 6372906.
+close();
+remove(_full_path);
+fail_stop("Unable to write to shared archive file.", NULL);
+}
+}
+_file_offset += nbytes;
+}
+// Align file position to an allocation unit boundary.
+void FileMapInfo::align_file_position() {
+size_t new_file_offset = align_size_up(_file_offset,
+os::vm_allocation_granularity());
+if (new_file_offset != _file_offset) {
+_file_offset = new_file_offset;
+if (_file_open) {
+// Seek one byte back from the target and write a byte to insure
+// that the written file is the correct length.
+_file_offset -= 1;
+if (lseek(_fd, (long)_file_offset, SEEK_SET) < 0) {
+fail_stop("Unable to seek.", NULL);
+}
+char zero = 0;
+write_bytes(&zero, 1);
+}
+}
+}
+// Dump bytes to file -- at the current file position.
+void FileMapInfo::write_bytes_aligned(const void* buffer, int nbytes) {
+align_file_position();
+write_bytes(buffer, nbytes);
+align_file_position();
+}
+// Close the shared archive file.  This does NOT unmap mapped regions.
+void FileMapInfo::close() {
+if (_file_open) {
+if (::close(_fd) < 0) {
+fail_stop("Unable to close the shared archive file.");
+}
+_file_open = false;
+_fd = -1;
+}
+}
+// JVM/TI RedefineClasses() support:
+// Remap the shared readonly space to shared readwrite, private.
+bool FileMapInfo::remap_shared_readonly_as_readwrite() {
+struct FileMapInfo::FileMapHeader::space_info* si = &_header._space[0];
+if (!si->_read_only) {
+// the space is already readwrite so we are done
+return true;
+}
+size_t used = si->_used;
+size_t size = align_size_up(used, os::vm_allocation_granularity());
+if (!open_for_read()) {
+return false;
+}
+char *base = os::remap_memory(_fd, _full_path, si->_file_offset,
+si->_base, size, false /* !read_only */,
+si->_allow_exec);
+close();
+if (base == NULL) {
+fail_continue("Unable to remap shared readonly space (errno=%d).", errno);
+return false;
+}
+if (base != si->_base) {
+fail_continue("Unable to remap shared readonly space at required address.");
+return false;
+}
+si->_read_only = false;
+return true;
+}
+// Map the whole region at once, assumed to be allocated contiguously.
+ReservedSpace FileMapInfo::reserve_shared_memory() {
+struct FileMapInfo::FileMapHeader::space_info* si = &_header._space[0];
+char* requested_addr = si->_base;
+size_t size = FileMapInfo::shared_spaces_size();
+// Reserve the space first, then map otherwise map will go right over some
+// other reserved memory (like the code cache).
+ReservedSpace rs(size, os::vm_allocation_granularity(), false, requested_addr);
+if (!rs.is_reserved()) {
+fail_continue(err_msg("Unable to reserve shared space at required address " INTPTR_FORMAT, requested_addr));
+return rs;
+}
+// the reserved virtual memory is for mapping class data sharing archive
+MemTracker::record_virtual_memory_type((address)rs.base(), mtClassShared);
+return rs;
+}
+// Memory map a region in the address space.
+static const char* shared_region_name[] = { "ReadOnly", "ReadWrite", "MiscData", "MiscCode"};
+char* FileMapInfo::map_region(int i) {
+struct FileMapInfo::FileMapHeader::space_info* si = &_header._space[i];
+size_t used = si->_used;
+size_t alignment = os::vm_allocation_granularity();
+size_t size = align_size_up(used, alignment);
+char *requested_addr = si->_base;
+// map the contents of the CDS archive in this memory
+char *base = os::map_memory(_fd, _full_path, si->_file_offset,
+requested_addr, size, si->_read_only,
+si->_allow_exec);
+if (base == NULL || base != si->_base) {
+fail_continue(err_msg("Unable to map %s shared space at required address.", shared_region_name[i]));
+return NULL;
+}
+#ifdef _WINDOWS
+// This call is Windows-only because the memory_type gets recorded for the other platforms
+// in method FileMapInfo::reserve_shared_memory(), which is not called on Windows.
+MemTracker::record_virtual_memory_type((address)base, mtClassShared);
+#endif
+return base;
+}
+bool FileMapInfo::verify_region_checksum(int i) {
+if (!VerifySharedSpaces) {
+return true;
+}
+const char* buf = _header._space[i]._base;
+size_t sz = _header._space[i]._used;
+int crc = ClassLoader::crc32(0, buf, (jint)sz);
+if (crc != _header._space[i]._crc) {
+fail_continue("Checksum verification failed.");
+return false;
+}
+return true;
+}
+// Unmap a memory region in the address space.
+void FileMapInfo::unmap_region(int i) {
+struct FileMapInfo::FileMapHeader::space_info* si = &_header._space[i];
+size_t used = si->_used;
+size_t size = align_size_up(used, os::vm_allocation_granularity());
+if (!os::unmap_memory(si->_base, size)) {
+fail_stop("Unable to unmap shared space.");
+}
+}
+void FileMapInfo::assert_mark(bool check) {
+if (!check) {
+fail_stop("Mark mismatch while restoring from shared file.", NULL);
+}
+}
+FileMapInfo* FileMapInfo::_current_info = NULL;
+// Open the shared archive file, read and validate the header
+// information (version, boot classpath, etc.).  If initialization
+// fails, shared spaces are disabled and the file is closed. [See
+// fail_continue.]
+bool FileMapInfo::initialize() {
+assert(UseSharedSpaces, "UseSharedSpaces expected.");
+if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space()) {
+fail_continue("Tool agent requires sharing to be disabled.");
+return false;
+}
+if (!open_for_read()) {
+return false;
+}
+init_from_file(_fd);
+if (!validate()) {
+return false;
+}
+SharedReadOnlySize =  _header._space[0]._capacity;
+SharedReadWriteSize = _header._space[1]._capacity;
+SharedMiscDataSize =  _header._space[2]._capacity;
+SharedMiscCodeSize =  _header._space[3]._capacity;
+return true;
+}
+int FileMapInfo::compute_header_crc() {
+char* header = (char*)&_header;
+// start computing from the field after _crc
+char* buf = (char*)&_header._crc + sizeof(int);
+size_t sz = sizeof(FileMapInfo::FileMapHeader) - (buf - header);
+int crc = ClassLoader::crc32(0, buf, (jint)sz);
+return crc;
+}
+bool FileMapInfo::validate() {
+if (VerifySharedSpaces && compute_header_crc() != _header._crc) {
+fail_continue("Header checksum verification failed.");
+return false;
+}
+if (_header._version != current_version()) {
+fail_continue("The shared archive file is the wrong version.");
+return false;
+}
+if (_header._magic != (int)0xf00baba2) {
+fail_continue("The shared archive file has a bad magic number.");
+return false;
+}
+char header_version[JVM_IDENT_MAX];
+get_header_version(header_version);
+if (strncmp(_header._jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) {
+fail_continue("The shared archive file was created by a different"
+" version or build of HotSpot.");
+return false;
+}
+if (_header._obj_alignment != ObjectAlignmentInBytes) {
+fail_continue("The shared archive file's ObjectAlignmentInBytes of %d"
+" does not equal the current ObjectAlignmentInBytes of %d.",
+_header._obj_alignment, ObjectAlignmentInBytes);
+return false;
+}
+// Cannot verify interpreter yet, as it can only be created after the GC
+// heap has been initialized.
+if (_header._num_jars >= JVM_SHARED_JARS_MAX) {
+fail_continue("Too many jar files to share.");
+return false;
+}
+// Build checks on classpath and jar files
+int num_jars_now = 0;
+ClassPathEntry *cpe = ClassLoader::classpath_entry(0);
+for ( ; cpe != NULL; cpe = cpe->next()) {
+if (cpe->is_jar_file()) {
+if (num_jars_now < _header._num_jars) {
+// Jar file - verify timestamp and file size.
+struct stat st;
+const char *path = cpe->name();
+if (os::stat(path, &st) != 0) {
+fail_continue("Unable to open jar file %s.", path);
+return false;
+}
+if (_header._jar[num_jars_now]._timestamp != st.st_mtime ||
+_header._jar[num_jars_now]._filesize != st.st_size) {
+fail_continue("A jar file is not the one used while building"
+" the shared archive file.");
+return false;
+}
+}
+++num_jars_now;
+} else {
+// If directories appear in boot classpath, they must be empty to
+// avoid having to verify each individual class file.
+const char* name = ((ClassPathDirEntry*)cpe)->name();
+if (!os::dir_is_empty(name)) {
+fail_continue("Boot classpath directory %s is not empty.", name);
+return false;
+}
+}
+}
+if (num_jars_now < _header._num_jars) {
+fail_continue("The number of jar files in the boot classpath is"
+" less than the number the shared archive was created with.");
+return false;
+}
+return true;
+}
+// The following method is provided to see whether a given pointer
+// falls in the mapped shared space.
+// Param:
+// p, The given pointer
+// Return:
+// True if the p is within the mapped shared space, otherwise, false.
+bool FileMapInfo::is_in_shared_space(const void* p) {
+for (int i = 0; i < MetaspaceShared::n_regions; i++) {
+if (p >= _header._space[i]._base &&
+p < _header._space[i]._base + _header._space[i]._used) {
+return true;
+}
+}
+return false;
+}
+void FileMapInfo::print_shared_spaces() {
+gclog_or_tty->print_cr("Shared Spaces:");
+for (int i = 0; i < MetaspaceShared::n_regions; i++) {
+struct FileMapInfo::FileMapHeader::space_info* si = &_header._space[i];
+gclog_or_tty->print("  %s " INTPTR_FORMAT "-" INTPTR_FORMAT,
+shared_region_name[i],
+si->_base, si->_base + si->_used);
+}
+}
+// Unmap mapped regions of shared space.
+void FileMapInfo::stop_sharing_and_unmap(const char* msg) {
+FileMapInfo *map_info = FileMapInfo::current_info();
+if (map_info) {
+map_info->fail_continue(msg);
+for (int i = 0; i < MetaspaceShared::n_regions; i++) {
+if (map_info->_header._space[i]._base != NULL) {
+map_info->unmap_region(i);
+map_info->_header._space[i]._base = NULL;
+}
+}
+} else if (DumpSharedSpaces) {
+fail_stop(msg, NULL);
+}
+}

Mercurial > jdk8-mips64-public > hotspot / file comparison

comparison: src/share/vm/memory/filemap.cpp

src/share/vm/memory/filemap.cpp