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Diffstat (limited to '')
| -rw-r--r-- | storage/rocksdb/rocksdb/env/fs_posix.cc | 913 |
1 files changed, 913 insertions, 0 deletions
diff --git a/storage/rocksdb/rocksdb/env/fs_posix.cc b/storage/rocksdb/rocksdb/env/fs_posix.cc new file mode 100644 index 00000000..0f1a41ac --- /dev/null +++ b/storage/rocksdb/rocksdb/env/fs_posix.cc @@ -0,0 +1,913 @@ +// Copyright (c) 2011-present, Facebook, Inc. All rights reserved. +// This source code is licensed under both the GPLv2 (found in the +// COPYING file in the root directory) and Apache 2.0 License +// (found in the LICENSE.Apache file in the root directory). +// +// Copyright (c) 2011 The LevelDB Authors. All rights reserved. +// Use of this source code is governed by a BSD-style license that can be +// found in the LICENSE file. See the AUTHORS file for names of contributors +#include <dirent.h> +#ifndef ROCKSDB_NO_DYNAMIC_EXTENSION +#include <dlfcn.h> +#endif +#include <errno.h> +#include <fcntl.h> + +#if defined(OS_LINUX) +#include <linux/fs.h> +#endif +#include <pthread.h> +#include <signal.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/ioctl.h> +#include <sys/mman.h> +#include <sys/stat.h> +#if defined(OS_LINUX) || defined(OS_SOLARIS) || defined(OS_ANDROID) +#include <sys/statfs.h> +#include <sys/syscall.h> +#include <sys/sysmacros.h> +#endif +#include <sys/statvfs.h> +#include <sys/time.h> +#include <sys/types.h> +#include <time.h> +#include <algorithm> +// Get nano time includes +#if defined(OS_LINUX) || defined(OS_FREEBSD) +#elif defined(__MACH__) +#include <Availability.h> +#include <mach/clock.h> +#include <mach/mach.h> +#else +#include <chrono> +#endif +#include <deque> +#include <set> +#include <vector> + +#include "env/io_posix.h" +#include "logging/logging.h" +#include "logging/posix_logger.h" +#include "monitoring/iostats_context_imp.h" +#include "monitoring/thread_status_updater.h" +#include "port/port.h" +#include "rocksdb/options.h" +#include "rocksdb/slice.h" +#include "test_util/sync_point.h" +#include "util/coding.h" +#include "util/compression_context_cache.h" +#include "util/random.h" +#include "util/string_util.h" +#include "util/thread_local.h" +#include "util/threadpool_imp.h" + +#if !defined(TMPFS_MAGIC) +#define TMPFS_MAGIC 0x01021994 +#endif +#if !defined(XFS_SUPER_MAGIC) +#define XFS_SUPER_MAGIC 0x58465342 +#endif +#if !defined(EXT4_SUPER_MAGIC) +#define EXT4_SUPER_MAGIC 0xEF53 +#endif + +namespace ROCKSDB_NAMESPACE { + +namespace { + +inline mode_t GetDBFileMode(bool allow_non_owner_access) { + return allow_non_owner_access ? 0644 : 0600; +} + +// list of pathnames that are locked +static std::set<std::string> lockedFiles; +static port::Mutex mutex_lockedFiles; + +static int LockOrUnlock(int fd, bool lock) { + errno = 0; + struct flock f; + memset(&f, 0, sizeof(f)); + f.l_type = (lock ? F_WRLCK : F_UNLCK); + f.l_whence = SEEK_SET; + f.l_start = 0; + f.l_len = 0; // Lock/unlock entire file + int value = fcntl(fd, F_SETLK, &f); + + return value; +} + +class PosixFileLock : public FileLock { + public: + int fd_; + std::string filename; +}; + +int cloexec_flags(int flags, const EnvOptions* options) { + // If the system supports opening the file with cloexec enabled, + // do so, as this avoids a race condition if a db is opened around + // the same time that a child process is forked +#ifdef O_CLOEXEC + if (options == nullptr || options->set_fd_cloexec) { + flags |= O_CLOEXEC; + } +#endif + return flags; +} + +class PosixFileSystem : public FileSystem { + public: + PosixFileSystem(); + + const char* Name() const override { return "Posix File System"; } + + ~PosixFileSystem() override {} + + void SetFD_CLOEXEC(int fd, const EnvOptions* options) { + if ((options == nullptr || options->set_fd_cloexec) && fd > 0) { + fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) | FD_CLOEXEC); + } + } + + IOStatus NewSequentialFile(const std::string& fname, + const FileOptions& options, + std::unique_ptr<FSSequentialFile>* result, + IODebugContext* /*dbg*/) override { + result->reset(); + int fd = -1; + int flags = cloexec_flags(O_RDONLY, &options); + FILE* file = nullptr; + + if (options.use_direct_reads && !options.use_mmap_reads) { +#ifdef ROCKSDB_LITE + return IOStatus::IOError(fname, + "Direct I/O not supported in RocksDB lite"); +#endif // !ROCKSDB_LITE +#if !defined(OS_MACOSX) && !defined(OS_OPENBSD) && !defined(OS_SOLARIS) + flags |= O_DIRECT; +#endif + } + + do { + IOSTATS_TIMER_GUARD(open_nanos); + fd = open(fname.c_str(), flags, GetDBFileMode(allow_non_owner_access_)); + } while (fd < 0 && errno == EINTR); + if (fd < 0) { + return IOError("While opening a file for sequentially reading", fname, + errno); + } + + SetFD_CLOEXEC(fd, &options); + + if (options.use_direct_reads && !options.use_mmap_reads) { +#ifdef OS_MACOSX + if (fcntl(fd, F_NOCACHE, 1) == -1) { + close(fd); + return IOError("While fcntl NoCache", fname, errno); + } +#endif + } else { + do { + IOSTATS_TIMER_GUARD(open_nanos); + file = fdopen(fd, "r"); + } while (file == nullptr && errno == EINTR); + if (file == nullptr) { + close(fd); + return IOError("While opening file for sequentially read", fname, + errno); + } + } + result->reset(new PosixSequentialFile(fname, file, fd, options)); + return IOStatus::OK(); + } + + IOStatus NewRandomAccessFile(const std::string& fname, + const FileOptions& options, + std::unique_ptr<FSRandomAccessFile>* result, + IODebugContext* /*dbg*/) override { + result->reset(); + IOStatus s; + int fd; + int flags = cloexec_flags(O_RDONLY, &options); + + if (options.use_direct_reads && !options.use_mmap_reads) { +#ifdef ROCKSDB_LITE + return IOStatus::IOError(fname, + "Direct I/O not supported in RocksDB lite"); +#endif // !ROCKSDB_LITE +#if !defined(OS_MACOSX) && !defined(OS_OPENBSD) && !defined(OS_SOLARIS) + flags |= O_DIRECT; + TEST_SYNC_POINT_CALLBACK("NewRandomAccessFile:O_DIRECT", &flags); +#endif + } + + do { + IOSTATS_TIMER_GUARD(open_nanos); + fd = open(fname.c_str(), flags, GetDBFileMode(allow_non_owner_access_)); + } while (fd < 0 && errno == EINTR); + if (fd < 0) { + return IOError("While open a file for random read", fname, errno); + } + SetFD_CLOEXEC(fd, &options); + + if (options.use_mmap_reads && sizeof(void*) >= 8) { + // Use of mmap for random reads has been removed because it + // kills performance when storage is fast. + // Use mmap when virtual address-space is plentiful. + uint64_t size; + IOOptions opts; + s = GetFileSize(fname, opts, &size, nullptr); + if (s.ok()) { + void* base = mmap(nullptr, size, PROT_READ, MAP_SHARED, fd, 0); + if (base != MAP_FAILED) { + result->reset( + new PosixMmapReadableFile(fd, fname, base, size, options)); + } else { + s = IOError("while mmap file for read", fname, errno); + close(fd); + } + } + } else { + if (options.use_direct_reads && !options.use_mmap_reads) { +#ifdef OS_MACOSX + if (fcntl(fd, F_NOCACHE, 1) == -1) { + close(fd); + return IOError("while fcntl NoCache", fname, errno); + } +#endif + } + result->reset(new PosixRandomAccessFile(fname, fd, options +#if defined(ROCKSDB_IOURING_PRESENT) + , + thread_local_io_urings_.get() +#endif + )); + } + return s; + } + + virtual IOStatus OpenWritableFile(const std::string& fname, + const FileOptions& options, + bool reopen, + std::unique_ptr<FSWritableFile>* result, + IODebugContext* /*dbg*/) { + result->reset(); + IOStatus s; + int fd = -1; + int flags = (reopen) ? (O_CREAT | O_APPEND) : (O_CREAT | O_TRUNC); + // Direct IO mode with O_DIRECT flag or F_NOCAHCE (MAC OSX) + if (options.use_direct_writes && !options.use_mmap_writes) { + // Note: we should avoid O_APPEND here due to ta the following bug: + // POSIX requires that opening a file with the O_APPEND flag should + // have no affect on the location at which pwrite() writes data. + // However, on Linux, if a file is opened with O_APPEND, pwrite() + // appends data to the end of the file, regardless of the value of + // offset. + // More info here: https://linux.die.net/man/2/pwrite +#ifdef ROCKSDB_LITE + return IOStatus::IOError(fname, + "Direct I/O not supported in RocksDB lite"); +#endif // ROCKSDB_LITE + flags |= O_WRONLY; +#if !defined(OS_MACOSX) && !defined(OS_OPENBSD) && !defined(OS_SOLARIS) + flags |= O_DIRECT; +#endif + TEST_SYNC_POINT_CALLBACK("NewWritableFile:O_DIRECT", &flags); + } else if (options.use_mmap_writes) { + // non-direct I/O + flags |= O_RDWR; + } else { + flags |= O_WRONLY; + } + + flags = cloexec_flags(flags, &options); + + do { + IOSTATS_TIMER_GUARD(open_nanos); + fd = open(fname.c_str(), flags, GetDBFileMode(allow_non_owner_access_)); + } while (fd < 0 && errno == EINTR); + + if (fd < 0) { + s = IOError("While open a file for appending", fname, errno); + return s; + } + SetFD_CLOEXEC(fd, &options); + + if (options.use_mmap_writes) { + if (!checkedDiskForMmap_) { + // this will be executed once in the program's lifetime. + // do not use mmapWrite on non ext-3/xfs/tmpfs systems. + if (!SupportsFastAllocate(fname)) { + forceMmapOff_ = true; + } + checkedDiskForMmap_ = true; + } + } + if (options.use_mmap_writes && !forceMmapOff_) { + result->reset(new PosixMmapFile(fname, fd, page_size_, options)); + } else if (options.use_direct_writes && !options.use_mmap_writes) { +#ifdef OS_MACOSX + if (fcntl(fd, F_NOCACHE, 1) == -1) { + close(fd); + s = IOError("While fcntl NoCache an opened file for appending", fname, + errno); + return s; + } +#elif defined(OS_SOLARIS) + if (directio(fd, DIRECTIO_ON) == -1) { + if (errno != ENOTTY) { // ZFS filesystems don't support DIRECTIO_ON + close(fd); + s = IOError("While calling directio()", fname, errno); + return s; + } + } +#endif + result->reset(new PosixWritableFile(fname, fd, options)); + } else { + // disable mmap writes + EnvOptions no_mmap_writes_options = options; + no_mmap_writes_options.use_mmap_writes = false; + result->reset(new PosixWritableFile(fname, fd, no_mmap_writes_options)); + } + return s; + } + + IOStatus NewWritableFile(const std::string& fname, const FileOptions& options, + std::unique_ptr<FSWritableFile>* result, + IODebugContext* dbg) override { + return OpenWritableFile(fname, options, false, result, dbg); + } + + IOStatus ReopenWritableFile(const std::string& fname, + const FileOptions& options, + std::unique_ptr<FSWritableFile>* result, + IODebugContext* dbg) override { + return OpenWritableFile(fname, options, true, result, dbg); + } + + IOStatus ReuseWritableFile(const std::string& fname, + const std::string& old_fname, + const FileOptions& options, + std::unique_ptr<FSWritableFile>* result, + IODebugContext* /*dbg*/) override { + result->reset(); + IOStatus s; + int fd = -1; + + int flags = 0; + // Direct IO mode with O_DIRECT flag or F_NOCAHCE (MAC OSX) + if (options.use_direct_writes && !options.use_mmap_writes) { +#ifdef ROCKSDB_LITE + return IOStatus::IOError(fname, + "Direct I/O not supported in RocksDB lite"); +#endif // !ROCKSDB_LITE + flags |= O_WRONLY; +#if !defined(OS_MACOSX) && !defined(OS_OPENBSD) && !defined(OS_SOLARIS) + flags |= O_DIRECT; +#endif + TEST_SYNC_POINT_CALLBACK("NewWritableFile:O_DIRECT", &flags); + } else if (options.use_mmap_writes) { + // mmap needs O_RDWR mode + flags |= O_RDWR; + } else { + flags |= O_WRONLY; + } + + flags = cloexec_flags(flags, &options); + + do { + IOSTATS_TIMER_GUARD(open_nanos); + fd = open(old_fname.c_str(), flags, + GetDBFileMode(allow_non_owner_access_)); + } while (fd < 0 && errno == EINTR); + if (fd < 0) { + s = IOError("while reopen file for write", fname, errno); + return s; + } + + SetFD_CLOEXEC(fd, &options); + // rename into place + if (rename(old_fname.c_str(), fname.c_str()) != 0) { + s = IOError("while rename file to " + fname, old_fname, errno); + close(fd); + return s; + } + + if (options.use_mmap_writes) { + if (!checkedDiskForMmap_) { + // this will be executed once in the program's lifetime. + // do not use mmapWrite on non ext-3/xfs/tmpfs systems. + if (!SupportsFastAllocate(fname)) { + forceMmapOff_ = true; + } + checkedDiskForMmap_ = true; + } + } + if (options.use_mmap_writes && !forceMmapOff_) { + result->reset(new PosixMmapFile(fname, fd, page_size_, options)); + } else if (options.use_direct_writes && !options.use_mmap_writes) { +#ifdef OS_MACOSX + if (fcntl(fd, F_NOCACHE, 1) == -1) { + close(fd); + s = IOError("while fcntl NoCache for reopened file for append", fname, + errno); + return s; + } +#elif defined(OS_SOLARIS) + if (directio(fd, DIRECTIO_ON) == -1) { + if (errno != ENOTTY) { // ZFS filesystems don't support DIRECTIO_ON + close(fd); + s = IOError("while calling directio()", fname, errno); + return s; + } + } +#endif + result->reset(new PosixWritableFile(fname, fd, options)); + } else { + // disable mmap writes + FileOptions no_mmap_writes_options = options; + no_mmap_writes_options.use_mmap_writes = false; + result->reset(new PosixWritableFile(fname, fd, no_mmap_writes_options)); + } + return s; + } + + IOStatus NewRandomRWFile(const std::string& fname, const FileOptions& options, + std::unique_ptr<FSRandomRWFile>* result, + IODebugContext* /*dbg*/) override { + int fd = -1; + int flags = cloexec_flags(O_RDWR, &options); + + while (fd < 0) { + IOSTATS_TIMER_GUARD(open_nanos); + + fd = open(fname.c_str(), flags, GetDBFileMode(allow_non_owner_access_)); + if (fd < 0) { + // Error while opening the file + if (errno == EINTR) { + continue; + } + return IOError("While open file for random read/write", fname, errno); + } + } + + SetFD_CLOEXEC(fd, &options); + result->reset(new PosixRandomRWFile(fname, fd, options)); + return IOStatus::OK(); + } + + IOStatus NewMemoryMappedFileBuffer( + const std::string& fname, + std::unique_ptr<MemoryMappedFileBuffer>* result) override { + int fd = -1; + IOStatus status; + int flags = cloexec_flags(O_RDWR, nullptr); + + while (fd < 0) { + IOSTATS_TIMER_GUARD(open_nanos); + fd = open(fname.c_str(), flags, 0644); + if (fd < 0) { + // Error while opening the file + if (errno == EINTR) { + continue; + } + status = + IOError("While open file for raw mmap buffer access", fname, errno); + break; + } + } + uint64_t size; + if (status.ok()) { + IOOptions opts; + status = GetFileSize(fname, opts, &size, nullptr); + } + void* base = nullptr; + if (status.ok()) { + base = mmap(nullptr, static_cast<size_t>(size), PROT_READ | PROT_WRITE, + MAP_SHARED, fd, 0); + if (base == MAP_FAILED) { + status = IOError("while mmap file for read", fname, errno); + } + } + if (status.ok()) { + result->reset( + new PosixMemoryMappedFileBuffer(base, static_cast<size_t>(size))); + } + if (fd >= 0) { + // don't need to keep it open after mmap has been called + close(fd); + } + return status; + } + + IOStatus NewDirectory(const std::string& name, const IOOptions& /*opts*/, + std::unique_ptr<FSDirectory>* result, + IODebugContext* /*dbg*/) override { + result->reset(); + int fd; + int flags = cloexec_flags(0, nullptr); + { + IOSTATS_TIMER_GUARD(open_nanos); + fd = open(name.c_str(), flags); + } + if (fd < 0) { + return IOError("While open directory", name, errno); + } else { + result->reset(new PosixDirectory(fd)); + } + return IOStatus::OK(); + } + + IOStatus NewLogger(const std::string& /*fname*/, const IOOptions& /*opts*/, + std::shared_ptr<ROCKSDB_NAMESPACE::Logger>* /*ptr*/, + IODebugContext* /*dbg*/) override { + return IOStatus::NotSupported(); + } + + IOStatus FileExists(const std::string& fname, const IOOptions& /*opts*/, + IODebugContext* /*dbg*/) override { + int result = access(fname.c_str(), F_OK); + + if (result == 0) { + return IOStatus::OK(); + } + + int err = errno; + switch (err) { + case EACCES: + case ELOOP: + case ENAMETOOLONG: + case ENOENT: + case ENOTDIR: + return IOStatus::NotFound(); + default: + assert(err == EIO || err == ENOMEM); + return IOStatus::IOError("Unexpected error(" + ToString(err) + + ") accessing file `" + fname + "' "); + } + } + + IOStatus GetChildren(const std::string& dir, const IOOptions& /*opts*/, + std::vector<std::string>* result, + IODebugContext* /*dbg*/) override { + result->clear(); + DIR* d = opendir(dir.c_str()); + if (d == nullptr) { + switch (errno) { + case EACCES: + case ENOENT: + case ENOTDIR: + return IOStatus::NotFound(); + default: + return IOError("While opendir", dir, errno); + } + } + struct dirent* entry; + while ((entry = readdir(d)) != nullptr) { + result->push_back(entry->d_name); + } + closedir(d); + return IOStatus::OK(); + } + + IOStatus DeleteFile(const std::string& fname, const IOOptions& /*opts*/, + IODebugContext* /*dbg*/) override { + IOStatus result; + if (unlink(fname.c_str()) != 0) { + result = IOError("while unlink() file", fname, errno); + } + return result; + } + + IOStatus CreateDir(const std::string& name, const IOOptions& /*opts*/, + IODebugContext* /*dbg*/) override { + IOStatus result; + if (mkdir(name.c_str(), 0755) != 0) { + result = IOError("While mkdir", name, errno); + } + return result; + } + + IOStatus CreateDirIfMissing(const std::string& name, + const IOOptions& /*opts*/, + IODebugContext* /*dbg*/) override { + IOStatus result; + if (mkdir(name.c_str(), 0755) != 0) { + if (errno != EEXIST) { + result = IOError("While mkdir if missing", name, errno); + } else if (!DirExists(name)) { // Check that name is actually a + // directory. + // Message is taken from mkdir + result = + IOStatus::IOError("`" + name + "' exists but is not a directory"); + } + } + return result; + } + + IOStatus DeleteDir(const std::string& name, const IOOptions& /*opts*/, + IODebugContext* /*dbg*/) override { + IOStatus result; + if (rmdir(name.c_str()) != 0) { + result = IOError("file rmdir", name, errno); + } + return result; + } + + IOStatus GetFileSize(const std::string& fname, const IOOptions& /*opts*/, + uint64_t* size, IODebugContext* /*dbg*/) override { + IOStatus s; + struct stat sbuf; + if (stat(fname.c_str(), &sbuf) != 0) { + *size = 0; + s = IOError("while stat a file for size", fname, errno); + } else { + *size = sbuf.st_size; + } + return s; + } + + IOStatus GetFileModificationTime(const std::string& fname, + const IOOptions& /*opts*/, + uint64_t* file_mtime, + IODebugContext* /*dbg*/) override { + struct stat s; + if (stat(fname.c_str(), &s) != 0) { + return IOError("while stat a file for modification time", fname, errno); + } + *file_mtime = static_cast<uint64_t>(s.st_mtime); + return IOStatus::OK(); + } + + IOStatus RenameFile(const std::string& src, const std::string& target, + const IOOptions& /*opts*/, + IODebugContext* /*dbg*/) override { + IOStatus result; + if (rename(src.c_str(), target.c_str()) != 0) { + result = IOError("While renaming a file to " + target, src, errno); + } + return result; + } + + IOStatus LinkFile(const std::string& src, const std::string& target, + const IOOptions& /*opts*/, + IODebugContext* /*dbg*/) override { + IOStatus result; + if (link(src.c_str(), target.c_str()) != 0) { + if (errno == EXDEV) { + return IOStatus::NotSupported("No cross FS links allowed"); + } + result = IOError("while link file to " + target, src, errno); + } + return result; + } + + IOStatus NumFileLinks(const std::string& fname, const IOOptions& /*opts*/, + uint64_t* count, IODebugContext* /*dbg*/) override { + struct stat s; + if (stat(fname.c_str(), &s) != 0) { + return IOError("while stat a file for num file links", fname, errno); + } + *count = static_cast<uint64_t>(s.st_nlink); + return IOStatus::OK(); + } + + IOStatus AreFilesSame(const std::string& first, const std::string& second, + const IOOptions& /*opts*/, bool* res, + IODebugContext* /*dbg*/) override { + struct stat statbuf[2]; + if (stat(first.c_str(), &statbuf[0]) != 0) { + return IOError("stat file", first, errno); + } + if (stat(second.c_str(), &statbuf[1]) != 0) { + return IOError("stat file", second, errno); + } + + if (major(statbuf[0].st_dev) != major(statbuf[1].st_dev) || + minor(statbuf[0].st_dev) != minor(statbuf[1].st_dev) || + statbuf[0].st_ino != statbuf[1].st_ino) { + *res = false; + } else { + *res = true; + } + return IOStatus::OK(); + } + + IOStatus LockFile(const std::string& fname, const IOOptions& /*opts*/, + FileLock** lock, IODebugContext* /*dbg*/) override { + *lock = nullptr; + IOStatus result; + + mutex_lockedFiles.Lock(); + // If it already exists in the lockedFiles set, then it is already locked, + // and fail this lock attempt. Otherwise, insert it into lockedFiles. + // This check is needed because fcntl() does not detect lock conflict + // if the fcntl is issued by the same thread that earlier acquired + // this lock. + // We must do this check *before* opening the file: + // Otherwise, we will open a new file descriptor. Locks are associated with + // a process, not a file descriptor and when *any* file descriptor is + // closed, all locks the process holds for that *file* are released + if (lockedFiles.insert(fname).second == false) { + mutex_lockedFiles.Unlock(); + errno = ENOLCK; + return IOError("lock ", fname, errno); + } + + int fd; + int flags = cloexec_flags(O_RDWR | O_CREAT, nullptr); + + { + IOSTATS_TIMER_GUARD(open_nanos); + fd = open(fname.c_str(), flags, 0644); + } + if (fd < 0) { + result = IOError("while open a file for lock", fname, errno); + } else if (LockOrUnlock(fd, true) == -1) { + // if there is an error in locking, then remove the pathname from + // lockedfiles + lockedFiles.erase(fname); + result = IOError("While lock file", fname, errno); + close(fd); + } else { + SetFD_CLOEXEC(fd, nullptr); + PosixFileLock* my_lock = new PosixFileLock; + my_lock->fd_ = fd; + my_lock->filename = fname; + *lock = my_lock; + } + + mutex_lockedFiles.Unlock(); + return result; + } + + IOStatus UnlockFile(FileLock* lock, const IOOptions& /*opts*/, + IODebugContext* /*dbg*/) override { + PosixFileLock* my_lock = reinterpret_cast<PosixFileLock*>(lock); + IOStatus result; + mutex_lockedFiles.Lock(); + // If we are unlocking, then verify that we had locked it earlier, + // it should already exist in lockedFiles. Remove it from lockedFiles. + if (lockedFiles.erase(my_lock->filename) != 1) { + errno = ENOLCK; + result = IOError("unlock", my_lock->filename, errno); + } else if (LockOrUnlock(my_lock->fd_, false) == -1) { + result = IOError("unlock", my_lock->filename, errno); + } + close(my_lock->fd_); + delete my_lock; + mutex_lockedFiles.Unlock(); + return result; + } + + IOStatus GetAbsolutePath(const std::string& db_path, + const IOOptions& /*opts*/, std::string* output_path, + IODebugContext* /*dbg*/) override { + if (!db_path.empty() && db_path[0] == '/') { + *output_path = db_path; + return IOStatus::OK(); + } + + char the_path[256]; + char* ret = getcwd(the_path, 256); + if (ret == nullptr) { + return IOStatus::IOError(strerror(errno)); + } + + *output_path = ret; + return IOStatus::OK(); + } + + IOStatus GetTestDirectory(const IOOptions& /*opts*/, std::string* result, + IODebugContext* /*dbg*/) override { + const char* env = getenv("TEST_TMPDIR"); + if (env && env[0] != '\0') { + *result = env; + } else { + char buf[100]; + snprintf(buf, sizeof(buf), "/tmp/rocksdbtest-%d", int(geteuid())); + *result = buf; + } + // Directory may already exist + { + IOOptions opts; + CreateDir(*result, opts, nullptr); + } + return IOStatus::OK(); + } + + IOStatus GetFreeSpace(const std::string& fname, const IOOptions& /*opts*/, + uint64_t* free_space, + IODebugContext* /*dbg*/) override { + struct statvfs sbuf; + + if (statvfs(fname.c_str(), &sbuf) < 0) { + return IOError("While doing statvfs", fname, errno); + } + + *free_space = ((uint64_t)sbuf.f_bsize * sbuf.f_bfree); + return IOStatus::OK(); + } + + FileOptions OptimizeForLogWrite(const FileOptions& file_options, + const DBOptions& db_options) const override { + FileOptions optimized = file_options; + optimized.use_mmap_writes = false; + optimized.use_direct_writes = false; + optimized.bytes_per_sync = db_options.wal_bytes_per_sync; + // TODO(icanadi) it's faster if fallocate_with_keep_size is false, but it + // breaks TransactionLogIteratorStallAtLastRecord unit test. Fix the unit + // test and make this false + optimized.fallocate_with_keep_size = true; + optimized.writable_file_max_buffer_size = + db_options.writable_file_max_buffer_size; + return optimized; + } + + FileOptions OptimizeForManifestWrite( + const FileOptions& file_options) const override { + FileOptions optimized = file_options; + optimized.use_mmap_writes = false; + optimized.use_direct_writes = false; + optimized.fallocate_with_keep_size = true; + return optimized; + } + + private: + bool checkedDiskForMmap_; + bool forceMmapOff_; // do we override Env options? + + // Returns true iff the named directory exists and is a directory. + virtual bool DirExists(const std::string& dname) { + struct stat statbuf; + if (stat(dname.c_str(), &statbuf) == 0) { + return S_ISDIR(statbuf.st_mode); + } + return false; // stat() failed return false + } + + bool SupportsFastAllocate(const std::string& path) { +#ifdef ROCKSDB_FALLOCATE_PRESENT + struct statfs s; + if (statfs(path.c_str(), &s)) { + return false; + } + switch (s.f_type) { + case EXT4_SUPER_MAGIC: + return true; + case XFS_SUPER_MAGIC: + return true; + case TMPFS_MAGIC: + return true; + default: + return false; + } +#else + (void)path; + return false; +#endif + } + +#if defined(ROCKSDB_IOURING_PRESENT) + // io_uring instance + std::unique_ptr<ThreadLocalPtr> thread_local_io_urings_; +#endif + + size_t page_size_; + + // If true, allow non owner read access for db files. Otherwise, non-owner + // has no access to db files. + bool allow_non_owner_access_; +}; + +PosixFileSystem::PosixFileSystem() + : checkedDiskForMmap_(false), + forceMmapOff_(false), + page_size_(getpagesize()), + allow_non_owner_access_(true) { +#if defined(ROCKSDB_IOURING_PRESENT) + // Test whether IOUring is supported, and if it does, create a managing + // object for thread local point so that in the future thread-local + // io_uring can be created. + struct io_uring* new_io_uring = CreateIOUring(); + if (new_io_uring != nullptr) { + thread_local_io_urings_.reset(new ThreadLocalPtr(DeleteIOUring)); + delete new_io_uring; + } +#endif +} + +} // namespace + +// +// Default Posix FileSystem +// +std::shared_ptr<FileSystem> FileSystem::Default() { + static PosixFileSystem default_fs; + static std::shared_ptr<PosixFileSystem> default_fs_ptr( + &default_fs, [](PosixFileSystem*) {}); + return default_fs_ptr; +} + +} // namespace ROCKSDB_NAMESPACE |