summaryrefslogtreecommitdiffstats
path: root/src/rocksdb/env/io_posix.cc
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--src/rocksdb/env/io_posix.cc1733
1 files changed, 1733 insertions, 0 deletions
diff --git a/src/rocksdb/env/io_posix.cc b/src/rocksdb/env/io_posix.cc
new file mode 100644
index 000000000..0ec0e9c83
--- /dev/null
+++ b/src/rocksdb/env/io_posix.cc
@@ -0,0 +1,1733 @@
+// 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.
+
+#ifdef ROCKSDB_LIB_IO_POSIX
+#include "env/io_posix.h"
+
+#include <errno.h>
+#include <fcntl.h>
+
+#include <algorithm>
+#if defined(OS_LINUX)
+#include <linux/fs.h>
+#ifndef FALLOC_FL_KEEP_SIZE
+#include <linux/falloc.h>
+#endif
+#endif
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#ifdef OS_LINUX
+#include <sys/statfs.h>
+#include <sys/sysmacros.h>
+#endif
+#include "monitoring/iostats_context_imp.h"
+#include "port/port.h"
+#include "port/stack_trace.h"
+#include "rocksdb/slice.h"
+#include "test_util/sync_point.h"
+#include "util/autovector.h"
+#include "util/coding.h"
+#include "util/string_util.h"
+
+#if defined(OS_LINUX) && !defined(F_SET_RW_HINT)
+#define F_LINUX_SPECIFIC_BASE 1024
+#define F_SET_RW_HINT (F_LINUX_SPECIFIC_BASE + 12)
+#endif
+
+namespace ROCKSDB_NAMESPACE {
+
+std::string IOErrorMsg(const std::string& context,
+ const std::string& file_name) {
+ if (file_name.empty()) {
+ return context;
+ }
+ return context + ": " + file_name;
+}
+
+// file_name can be left empty if it is not unkown.
+IOStatus IOError(const std::string& context, const std::string& file_name,
+ int err_number) {
+ switch (err_number) {
+ case ENOSPC: {
+ IOStatus s = IOStatus::NoSpace(IOErrorMsg(context, file_name),
+ errnoStr(err_number).c_str());
+ s.SetRetryable(true);
+ return s;
+ }
+ case ESTALE:
+ return IOStatus::IOError(IOStatus::kStaleFile);
+ case ENOENT:
+ return IOStatus::PathNotFound(IOErrorMsg(context, file_name),
+ errnoStr(err_number).c_str());
+ default:
+ return IOStatus::IOError(IOErrorMsg(context, file_name),
+ errnoStr(err_number).c_str());
+ }
+}
+
+// A wrapper for fadvise, if the platform doesn't support fadvise,
+// it will simply return 0.
+int Fadvise(int fd, off_t offset, size_t len, int advice) {
+#ifdef OS_LINUX
+ return posix_fadvise(fd, offset, len, advice);
+#else
+ (void)fd;
+ (void)offset;
+ (void)len;
+ (void)advice;
+ return 0; // simply do nothing.
+#endif
+}
+
+// A wrapper for fadvise, if the platform doesn't support fadvise,
+// it will simply return 0.
+int Madvise(void* addr, size_t len, int advice) {
+#ifdef OS_LINUX
+ return posix_madvise(addr, len, advice);
+#else
+ (void)addr;
+ (void)len;
+ (void)advice;
+ return 0; // simply do nothing.
+#endif
+}
+
+namespace {
+
+// On MacOS (and probably *BSD), the posix write and pwrite calls do not support
+// buffers larger than 2^31-1 bytes. These two wrappers fix this issue by
+// cutting the buffer in 1GB chunks. We use this chunk size to be sure to keep
+// the writes aligned.
+
+bool PosixWrite(int fd, const char* buf, size_t nbyte) {
+ const size_t kLimit1Gb = 1UL << 30;
+
+ const char* src = buf;
+ size_t left = nbyte;
+
+ while (left != 0) {
+ size_t bytes_to_write = std::min(left, kLimit1Gb);
+
+ ssize_t done = write(fd, src, bytes_to_write);
+ if (done < 0) {
+ if (errno == EINTR) {
+ continue;
+ }
+ return false;
+ }
+ left -= done;
+ src += done;
+ }
+ return true;
+}
+
+bool PosixPositionedWrite(int fd, const char* buf, size_t nbyte, off_t offset) {
+ const size_t kLimit1Gb = 1UL << 30;
+
+ const char* src = buf;
+ size_t left = nbyte;
+
+ while (left != 0) {
+ size_t bytes_to_write = std::min(left, kLimit1Gb);
+
+ ssize_t done = pwrite(fd, src, bytes_to_write, offset);
+ if (done < 0) {
+ if (errno == EINTR) {
+ continue;
+ }
+ return false;
+ }
+ left -= done;
+ offset += done;
+ src += done;
+ }
+
+ return true;
+}
+
+#ifdef ROCKSDB_RANGESYNC_PRESENT
+
+#if !defined(ZFS_SUPER_MAGIC)
+// The magic number for ZFS was not exposed until recently. It should be fixed
+// forever so we can just copy the magic number here.
+#define ZFS_SUPER_MAGIC 0x2fc12fc1
+#endif
+
+bool IsSyncFileRangeSupported(int fd) {
+ // This function tracks and checks for cases where we know `sync_file_range`
+ // definitely will not work properly despite passing the compile-time check
+ // (`ROCKSDB_RANGESYNC_PRESENT`). If we are unsure, or if any of the checks
+ // fail in unexpected ways, we allow `sync_file_range` to be used. This way
+ // should minimize risk of impacting existing use cases.
+ struct statfs buf;
+ int ret = fstatfs(fd, &buf);
+ assert(ret == 0);
+ if (ret == 0 && buf.f_type == ZFS_SUPER_MAGIC) {
+ // Testing on ZFS showed the writeback did not happen asynchronously when
+ // `sync_file_range` was called, even though it returned success. Avoid it
+ // and use `fdatasync` instead to preserve the contract of `bytes_per_sync`,
+ // even though this'll incur extra I/O for metadata.
+ return false;
+ }
+
+ ret = sync_file_range(fd, 0 /* offset */, 0 /* nbytes */, 0 /* flags */);
+ assert(!(ret == -1 && errno != ENOSYS));
+ if (ret == -1 && errno == ENOSYS) {
+ // `sync_file_range` is not implemented on all platforms even if
+ // compile-time checks pass and a supported filesystem is in-use. For
+ // example, using ext4 on WSL (Windows Subsystem for Linux),
+ // `sync_file_range()` returns `ENOSYS`
+ // ("Function not implemented").
+ return false;
+ }
+ // None of the known cases matched, so allow `sync_file_range` use.
+ return true;
+}
+
+#undef ZFS_SUPER_MAGIC
+
+#endif // ROCKSDB_RANGESYNC_PRESENT
+
+} // anonymous namespace
+
+/*
+ * PosixSequentialFile
+ */
+PosixSequentialFile::PosixSequentialFile(const std::string& fname, FILE* file,
+ int fd, size_t logical_block_size,
+ const EnvOptions& options)
+ : filename_(fname),
+ file_(file),
+ fd_(fd),
+ use_direct_io_(options.use_direct_reads),
+ logical_sector_size_(logical_block_size) {
+ assert(!options.use_direct_reads || !options.use_mmap_reads);
+}
+
+PosixSequentialFile::~PosixSequentialFile() {
+ if (!use_direct_io()) {
+ assert(file_);
+ fclose(file_);
+ } else {
+ assert(fd_);
+ close(fd_);
+ }
+}
+
+IOStatus PosixSequentialFile::Read(size_t n, const IOOptions& /*opts*/,
+ Slice* result, char* scratch,
+ IODebugContext* /*dbg*/) {
+ assert(result != nullptr && !use_direct_io());
+ IOStatus s;
+ size_t r = 0;
+ do {
+ clearerr(file_);
+ r = fread_unlocked(scratch, 1, n, file_);
+ } while (r == 0 && ferror(file_) && errno == EINTR);
+ *result = Slice(scratch, r);
+ if (r < n) {
+ if (feof(file_)) {
+ // We leave status as ok if we hit the end of the file
+ // We also clear the error so that the reads can continue
+ // if a new data is written to the file
+ clearerr(file_);
+ } else {
+ // A partial read with an error: return a non-ok status
+ s = IOError("While reading file sequentially", filename_, errno);
+ }
+ }
+ return s;
+}
+
+IOStatus PosixSequentialFile::PositionedRead(uint64_t offset, size_t n,
+ const IOOptions& /*opts*/,
+ Slice* result, char* scratch,
+ IODebugContext* /*dbg*/) {
+ assert(use_direct_io());
+ assert(IsSectorAligned(offset, GetRequiredBufferAlignment()));
+ assert(IsSectorAligned(n, GetRequiredBufferAlignment()));
+ assert(IsSectorAligned(scratch, GetRequiredBufferAlignment()));
+
+ IOStatus s;
+ ssize_t r = -1;
+ size_t left = n;
+ char* ptr = scratch;
+ while (left > 0) {
+ r = pread(fd_, ptr, left, static_cast<off_t>(offset));
+ if (r <= 0) {
+ if (r == -1 && errno == EINTR) {
+ continue;
+ }
+ break;
+ }
+ ptr += r;
+ offset += r;
+ left -= r;
+ if (!IsSectorAligned(r, GetRequiredBufferAlignment())) {
+ // Bytes reads don't fill sectors. Should only happen at the end
+ // of the file.
+ break;
+ }
+ }
+ if (r < 0) {
+ // An error: return a non-ok status
+ s = IOError("While pread " + std::to_string(n) + " bytes from offset " +
+ std::to_string(offset),
+ filename_, errno);
+ }
+ *result = Slice(scratch, (r < 0) ? 0 : n - left);
+ return s;
+}
+
+IOStatus PosixSequentialFile::Skip(uint64_t n) {
+ if (fseek(file_, static_cast<long int>(n), SEEK_CUR)) {
+ return IOError("While fseek to skip " + std::to_string(n) + " bytes",
+ filename_, errno);
+ }
+ return IOStatus::OK();
+}
+
+IOStatus PosixSequentialFile::InvalidateCache(size_t offset, size_t length) {
+#ifndef OS_LINUX
+ (void)offset;
+ (void)length;
+ return IOStatus::OK();
+#else
+ if (!use_direct_io()) {
+ // free OS pages
+ int ret = Fadvise(fd_, offset, length, POSIX_FADV_DONTNEED);
+ if (ret != 0) {
+ return IOError("While fadvise NotNeeded offset " +
+ std::to_string(offset) + " len " +
+ std::to_string(length),
+ filename_, errno);
+ }
+ }
+ return IOStatus::OK();
+#endif
+}
+
+/*
+ * PosixRandomAccessFile
+ */
+#if defined(OS_LINUX)
+size_t PosixHelper::GetUniqueIdFromFile(int fd, char* id, size_t max_size) {
+ if (max_size < kMaxVarint64Length * 3) {
+ return 0;
+ }
+
+ struct stat buf;
+ int result = fstat(fd, &buf);
+ if (result == -1) {
+ return 0;
+ }
+
+ long version = 0;
+ result = ioctl(fd, FS_IOC_GETVERSION, &version);
+ TEST_SYNC_POINT_CALLBACK("GetUniqueIdFromFile:FS_IOC_GETVERSION", &result);
+ if (result == -1) {
+ return 0;
+ }
+ uint64_t uversion = (uint64_t)version;
+
+ char* rid = id;
+ rid = EncodeVarint64(rid, buf.st_dev);
+ rid = EncodeVarint64(rid, buf.st_ino);
+ rid = EncodeVarint64(rid, uversion);
+ assert(rid >= id);
+ return static_cast<size_t>(rid - id);
+}
+#endif
+
+#if defined(OS_MACOSX) || defined(OS_AIX)
+size_t PosixHelper::GetUniqueIdFromFile(int fd, char* id, size_t max_size) {
+ if (max_size < kMaxVarint64Length * 3) {
+ return 0;
+ }
+
+ struct stat buf;
+ int result = fstat(fd, &buf);
+ if (result == -1) {
+ return 0;
+ }
+
+ char* rid = id;
+ rid = EncodeVarint64(rid, buf.st_dev);
+ rid = EncodeVarint64(rid, buf.st_ino);
+ rid = EncodeVarint64(rid, buf.st_gen);
+ assert(rid >= id);
+ return static_cast<size_t>(rid - id);
+}
+#endif
+
+#ifdef OS_LINUX
+std::string RemoveTrailingSlash(const std::string& path) {
+ std::string p = path;
+ if (p.size() > 1 && p.back() == '/') {
+ p.pop_back();
+ }
+ return p;
+}
+
+Status LogicalBlockSizeCache::RefAndCacheLogicalBlockSize(
+ const std::vector<std::string>& directories) {
+ std::vector<std::string> dirs;
+ dirs.reserve(directories.size());
+ for (auto& d : directories) {
+ dirs.emplace_back(RemoveTrailingSlash(d));
+ }
+
+ std::map<std::string, size_t> dir_sizes;
+ {
+ ReadLock lock(&cache_mutex_);
+ for (const auto& dir : dirs) {
+ if (cache_.find(dir) == cache_.end()) {
+ dir_sizes.emplace(dir, 0);
+ }
+ }
+ }
+
+ Status s;
+ for (auto& dir_size : dir_sizes) {
+ s = get_logical_block_size_of_directory_(dir_size.first, &dir_size.second);
+ if (!s.ok()) {
+ return s;
+ }
+ }
+
+ WriteLock lock(&cache_mutex_);
+ for (const auto& dir : dirs) {
+ auto& v = cache_[dir];
+ v.ref++;
+ auto dir_size = dir_sizes.find(dir);
+ if (dir_size != dir_sizes.end()) {
+ v.size = dir_size->second;
+ }
+ }
+ return s;
+}
+
+void LogicalBlockSizeCache::UnrefAndTryRemoveCachedLogicalBlockSize(
+ const std::vector<std::string>& directories) {
+ std::vector<std::string> dirs;
+ dirs.reserve(directories.size());
+ for (auto& dir : directories) {
+ dirs.emplace_back(RemoveTrailingSlash(dir));
+ }
+
+ WriteLock lock(&cache_mutex_);
+ for (const auto& dir : dirs) {
+ auto it = cache_.find(dir);
+ if (it != cache_.end() && !(--(it->second.ref))) {
+ cache_.erase(it);
+ }
+ }
+}
+
+size_t LogicalBlockSizeCache::GetLogicalBlockSize(const std::string& fname,
+ int fd) {
+ std::string dir = fname.substr(0, fname.find_last_of("/"));
+ if (dir.empty()) {
+ dir = "/";
+ }
+ {
+ ReadLock lock(&cache_mutex_);
+ auto it = cache_.find(dir);
+ if (it != cache_.end()) {
+ return it->second.size;
+ }
+ }
+ return get_logical_block_size_of_fd_(fd);
+}
+#endif
+
+Status PosixHelper::GetLogicalBlockSizeOfDirectory(const std::string& directory,
+ size_t* size) {
+ int fd = open(directory.c_str(), O_DIRECTORY | O_RDONLY);
+ if (fd == -1) {
+ close(fd);
+ return Status::IOError("Cannot open directory " + directory);
+ }
+ *size = PosixHelper::GetLogicalBlockSizeOfFd(fd);
+ close(fd);
+ return Status::OK();
+}
+
+size_t PosixHelper::GetLogicalBlockSizeOfFd(int fd) {
+#ifdef OS_LINUX
+ struct stat buf;
+ int result = fstat(fd, &buf);
+ if (result == -1) {
+ return kDefaultPageSize;
+ }
+ if (major(buf.st_dev) == 0) {
+ // Unnamed devices (e.g. non-device mounts), reserved as null device number.
+ // These don't have an entry in /sys/dev/block/. Return a sensible default.
+ return kDefaultPageSize;
+ }
+
+ // Reading queue/logical_block_size does not require special permissions.
+ const int kBufferSize = 100;
+ char path[kBufferSize];
+ char real_path[PATH_MAX + 1];
+ snprintf(path, kBufferSize, "/sys/dev/block/%u:%u", major(buf.st_dev),
+ minor(buf.st_dev));
+ if (realpath(path, real_path) == nullptr) {
+ return kDefaultPageSize;
+ }
+ std::string device_dir(real_path);
+ if (!device_dir.empty() && device_dir.back() == '/') {
+ device_dir.pop_back();
+ }
+ // NOTE: sda3 and nvme0n1p1 do not have a `queue/` subdir, only the parent sda
+ // and nvme0n1 have it.
+ // $ ls -al '/sys/dev/block/8:3'
+ // lrwxrwxrwx. 1 root root 0 Jun 26 01:38 /sys/dev/block/8:3 ->
+ // ../../block/sda/sda3
+ // $ ls -al '/sys/dev/block/259:4'
+ // lrwxrwxrwx 1 root root 0 Jan 31 16:04 /sys/dev/block/259:4 ->
+ // ../../devices/pci0000:17/0000:17:00.0/0000:18:00.0/nvme/nvme0/nvme0n1/nvme0n1p1
+ size_t parent_end = device_dir.rfind('/', device_dir.length() - 1);
+ if (parent_end == std::string::npos) {
+ return kDefaultPageSize;
+ }
+ size_t parent_begin = device_dir.rfind('/', parent_end - 1);
+ if (parent_begin == std::string::npos) {
+ return kDefaultPageSize;
+ }
+ std::string parent =
+ device_dir.substr(parent_begin + 1, parent_end - parent_begin - 1);
+ std::string child = device_dir.substr(parent_end + 1, std::string::npos);
+ if (parent != "block" &&
+ (child.compare(0, 4, "nvme") || child.find('p') != std::string::npos)) {
+ device_dir = device_dir.substr(0, parent_end);
+ }
+ std::string fname = device_dir + "/queue/logical_block_size";
+ FILE* fp;
+ size_t size = 0;
+ fp = fopen(fname.c_str(), "r");
+ if (fp != nullptr) {
+ char* line = nullptr;
+ size_t len = 0;
+ if (getline(&line, &len, fp) != -1) {
+ sscanf(line, "%zu", &size);
+ }
+ free(line);
+ fclose(fp);
+ }
+ if (size != 0 && (size & (size - 1)) == 0) {
+ return size;
+ }
+#endif
+ (void)fd;
+ return kDefaultPageSize;
+}
+
+/*
+ * PosixRandomAccessFile
+ *
+ * pread() based random-access
+ */
+PosixRandomAccessFile::PosixRandomAccessFile(
+ const std::string& fname, int fd, size_t logical_block_size,
+ const EnvOptions& options
+#if defined(ROCKSDB_IOURING_PRESENT)
+ ,
+ ThreadLocalPtr* thread_local_io_urings
+#endif
+ )
+ : filename_(fname),
+ fd_(fd),
+ use_direct_io_(options.use_direct_reads),
+ logical_sector_size_(logical_block_size)
+#if defined(ROCKSDB_IOURING_PRESENT)
+ ,
+ thread_local_io_urings_(thread_local_io_urings)
+#endif
+{
+ assert(!options.use_direct_reads || !options.use_mmap_reads);
+ assert(!options.use_mmap_reads);
+}
+
+PosixRandomAccessFile::~PosixRandomAccessFile() { close(fd_); }
+
+IOStatus PosixRandomAccessFile::Read(uint64_t offset, size_t n,
+ const IOOptions& /*opts*/, Slice* result,
+ char* scratch,
+ IODebugContext* /*dbg*/) const {
+ if (use_direct_io()) {
+ assert(IsSectorAligned(offset, GetRequiredBufferAlignment()));
+ assert(IsSectorAligned(n, GetRequiredBufferAlignment()));
+ assert(IsSectorAligned(scratch, GetRequiredBufferAlignment()));
+ }
+ IOStatus s;
+ ssize_t r = -1;
+ size_t left = n;
+ char* ptr = scratch;
+ while (left > 0) {
+ r = pread(fd_, ptr, left, static_cast<off_t>(offset));
+ if (r <= 0) {
+ if (r == -1 && errno == EINTR) {
+ continue;
+ }
+ break;
+ }
+ ptr += r;
+ offset += r;
+ left -= r;
+ if (use_direct_io() &&
+ r % static_cast<ssize_t>(GetRequiredBufferAlignment()) != 0) {
+ // Bytes reads don't fill sectors. Should only happen at the end
+ // of the file.
+ break;
+ }
+ }
+ if (r < 0) {
+ // An error: return a non-ok status
+ s = IOError("While pread offset " + std::to_string(offset) + " len " +
+ std::to_string(n),
+ filename_, errno);
+ }
+ *result = Slice(scratch, (r < 0) ? 0 : n - left);
+ return s;
+}
+
+IOStatus PosixRandomAccessFile::MultiRead(FSReadRequest* reqs, size_t num_reqs,
+ const IOOptions& options,
+ IODebugContext* dbg) {
+ if (use_direct_io()) {
+ for (size_t i = 0; i < num_reqs; i++) {
+ assert(IsSectorAligned(reqs[i].offset, GetRequiredBufferAlignment()));
+ assert(IsSectorAligned(reqs[i].len, GetRequiredBufferAlignment()));
+ assert(IsSectorAligned(reqs[i].scratch, GetRequiredBufferAlignment()));
+ }
+ }
+
+#if defined(ROCKSDB_IOURING_PRESENT)
+ struct io_uring* iu = nullptr;
+ if (thread_local_io_urings_) {
+ iu = static_cast<struct io_uring*>(thread_local_io_urings_->Get());
+ if (iu == nullptr) {
+ iu = CreateIOUring();
+ if (iu != nullptr) {
+ thread_local_io_urings_->Reset(iu);
+ }
+ }
+ }
+
+ // Init failed, platform doesn't support io_uring. Fall back to
+ // serialized reads
+ if (iu == nullptr) {
+ return FSRandomAccessFile::MultiRead(reqs, num_reqs, options, dbg);
+ }
+
+ IOStatus ios = IOStatus::OK();
+
+ struct WrappedReadRequest {
+ FSReadRequest* req;
+ struct iovec iov;
+ size_t finished_len;
+ explicit WrappedReadRequest(FSReadRequest* r) : req(r), finished_len(0) {}
+ };
+
+ autovector<WrappedReadRequest, 32> req_wraps;
+ autovector<WrappedReadRequest*, 4> incomplete_rq_list;
+ std::unordered_set<WrappedReadRequest*> wrap_cache;
+
+ for (size_t i = 0; i < num_reqs; i++) {
+ req_wraps.emplace_back(&reqs[i]);
+ }
+
+ size_t reqs_off = 0;
+ while (num_reqs > reqs_off || !incomplete_rq_list.empty()) {
+ size_t this_reqs = (num_reqs - reqs_off) + incomplete_rq_list.size();
+
+ // If requests exceed depth, split it into batches
+ if (this_reqs > kIoUringDepth) this_reqs = kIoUringDepth;
+
+ assert(incomplete_rq_list.size() <= this_reqs);
+ for (size_t i = 0; i < this_reqs; i++) {
+ WrappedReadRequest* rep_to_submit;
+ if (i < incomplete_rq_list.size()) {
+ rep_to_submit = incomplete_rq_list[i];
+ } else {
+ rep_to_submit = &req_wraps[reqs_off++];
+ }
+ assert(rep_to_submit->req->len > rep_to_submit->finished_len);
+ rep_to_submit->iov.iov_base =
+ rep_to_submit->req->scratch + rep_to_submit->finished_len;
+ rep_to_submit->iov.iov_len =
+ rep_to_submit->req->len - rep_to_submit->finished_len;
+
+ struct io_uring_sqe* sqe;
+ sqe = io_uring_get_sqe(iu);
+ io_uring_prep_readv(
+ sqe, fd_, &rep_to_submit->iov, 1,
+ rep_to_submit->req->offset + rep_to_submit->finished_len);
+ io_uring_sqe_set_data(sqe, rep_to_submit);
+ wrap_cache.emplace(rep_to_submit);
+ }
+ incomplete_rq_list.clear();
+
+ ssize_t ret =
+ io_uring_submit_and_wait(iu, static_cast<unsigned int>(this_reqs));
+ TEST_SYNC_POINT_CALLBACK(
+ "PosixRandomAccessFile::MultiRead:io_uring_submit_and_wait:return1",
+ &ret);
+ TEST_SYNC_POINT_CALLBACK(
+ "PosixRandomAccessFile::MultiRead:io_uring_submit_and_wait:return2",
+ iu);
+
+ if (static_cast<size_t>(ret) != this_reqs) {
+ fprintf(stderr, "ret = %ld this_reqs: %ld\n", (long)ret, (long)this_reqs);
+ // If error happens and we submitted fewer than expected, it is an
+ // exception case and we don't retry here. We should still consume
+ // what is is submitted in the ring.
+ for (ssize_t i = 0; i < ret; i++) {
+ struct io_uring_cqe* cqe = nullptr;
+ io_uring_wait_cqe(iu, &cqe);
+ if (cqe != nullptr) {
+ io_uring_cqe_seen(iu, cqe);
+ }
+ }
+ return IOStatus::IOError("io_uring_submit_and_wait() requested " +
+ std::to_string(this_reqs) + " but returned " +
+ std::to_string(ret));
+ }
+
+ for (size_t i = 0; i < this_reqs; i++) {
+ struct io_uring_cqe* cqe = nullptr;
+ WrappedReadRequest* req_wrap;
+
+ // We could use the peek variant here, but this seems safer in terms
+ // of our initial wait not reaping all completions
+ ret = io_uring_wait_cqe(iu, &cqe);
+ TEST_SYNC_POINT_CALLBACK(
+ "PosixRandomAccessFile::MultiRead:io_uring_wait_cqe:return", &ret);
+ if (ret) {
+ ios = IOStatus::IOError("io_uring_wait_cqe() returns " +
+ std::to_string(ret));
+
+ if (cqe != nullptr) {
+ io_uring_cqe_seen(iu, cqe);
+ }
+ continue;
+ }
+
+ req_wrap = static_cast<WrappedReadRequest*>(io_uring_cqe_get_data(cqe));
+ // Reset cqe data to catch any stray reuse of it
+ static_cast<struct io_uring_cqe*>(cqe)->user_data = 0xd5d5d5d5d5d5d5d5;
+ // Check that we got a valid unique cqe data
+ auto wrap_check = wrap_cache.find(req_wrap);
+ if (wrap_check == wrap_cache.end()) {
+ fprintf(stderr,
+ "PosixRandomAccessFile::MultiRead: "
+ "Bad cqe data from IO uring - %p\n",
+ req_wrap);
+ port::PrintStack();
+ ios = IOStatus::IOError("io_uring_cqe_get_data() returned " +
+ std::to_string((uint64_t)req_wrap));
+ continue;
+ }
+ wrap_cache.erase(wrap_check);
+
+ FSReadRequest* req = req_wrap->req;
+ size_t bytes_read = 0;
+ bool read_again = false;
+ UpdateResult(cqe, filename_, req->len, req_wrap->iov.iov_len,
+ false /*async_read*/, use_direct_io(),
+ GetRequiredBufferAlignment(), req_wrap->finished_len, req,
+ bytes_read, read_again);
+ int32_t res = cqe->res;
+ if (res >= 0) {
+ if (bytes_read == 0) {
+ if (read_again) {
+ Slice tmp_slice;
+ req->status =
+ Read(req->offset + req_wrap->finished_len,
+ req->len - req_wrap->finished_len, options, &tmp_slice,
+ req->scratch + req_wrap->finished_len, dbg);
+ req->result =
+ Slice(req->scratch, req_wrap->finished_len + tmp_slice.size());
+ }
+ // else It means EOF so no need to do anything.
+ } else if (bytes_read < req_wrap->iov.iov_len) {
+ incomplete_rq_list.push_back(req_wrap);
+ }
+ }
+ io_uring_cqe_seen(iu, cqe);
+ }
+ wrap_cache.clear();
+ }
+ return ios;
+#else
+ return FSRandomAccessFile::MultiRead(reqs, num_reqs, options, dbg);
+#endif
+}
+
+IOStatus PosixRandomAccessFile::Prefetch(uint64_t offset, size_t n,
+ const IOOptions& /*opts*/,
+ IODebugContext* /*dbg*/) {
+ IOStatus s;
+ if (!use_direct_io()) {
+ ssize_t r = 0;
+#ifdef OS_LINUX
+ r = readahead(fd_, offset, n);
+#endif
+#ifdef OS_MACOSX
+ radvisory advice;
+ advice.ra_offset = static_cast<off_t>(offset);
+ advice.ra_count = static_cast<int>(n);
+ r = fcntl(fd_, F_RDADVISE, &advice);
+#endif
+ if (r == -1) {
+ s = IOError("While prefetching offset " + std::to_string(offset) +
+ " len " + std::to_string(n),
+ filename_, errno);
+ }
+ }
+ return s;
+}
+
+#if defined(OS_LINUX) || defined(OS_MACOSX) || defined(OS_AIX)
+size_t PosixRandomAccessFile::GetUniqueId(char* id, size_t max_size) const {
+ return PosixHelper::GetUniqueIdFromFile(fd_, id, max_size);
+}
+#endif
+
+void PosixRandomAccessFile::Hint(AccessPattern pattern) {
+ if (use_direct_io()) {
+ return;
+ }
+ switch (pattern) {
+ case kNormal:
+ Fadvise(fd_, 0, 0, POSIX_FADV_NORMAL);
+ break;
+ case kRandom:
+ Fadvise(fd_, 0, 0, POSIX_FADV_RANDOM);
+ break;
+ case kSequential:
+ Fadvise(fd_, 0, 0, POSIX_FADV_SEQUENTIAL);
+ break;
+ case kWillNeed:
+ Fadvise(fd_, 0, 0, POSIX_FADV_WILLNEED);
+ break;
+ case kWontNeed:
+ Fadvise(fd_, 0, 0, POSIX_FADV_DONTNEED);
+ break;
+ default:
+ assert(false);
+ break;
+ }
+}
+
+IOStatus PosixRandomAccessFile::InvalidateCache(size_t offset, size_t length) {
+ if (use_direct_io()) {
+ return IOStatus::OK();
+ }
+#ifndef OS_LINUX
+ (void)offset;
+ (void)length;
+ return IOStatus::OK();
+#else
+ // free OS pages
+ int ret = Fadvise(fd_, offset, length, POSIX_FADV_DONTNEED);
+ if (ret == 0) {
+ return IOStatus::OK();
+ }
+ return IOError("While fadvise NotNeeded offset " + std::to_string(offset) +
+ " len " + std::to_string(length),
+ filename_, errno);
+#endif
+}
+
+IOStatus PosixRandomAccessFile::ReadAsync(
+ FSReadRequest& req, const IOOptions& /*opts*/,
+ std::function<void(const FSReadRequest&, void*)> cb, void* cb_arg,
+ void** io_handle, IOHandleDeleter* del_fn, IODebugContext* /*dbg*/) {
+ if (use_direct_io()) {
+ assert(IsSectorAligned(req.offset, GetRequiredBufferAlignment()));
+ assert(IsSectorAligned(req.len, GetRequiredBufferAlignment()));
+ assert(IsSectorAligned(req.scratch, GetRequiredBufferAlignment()));
+ }
+
+#if defined(ROCKSDB_IOURING_PRESENT)
+ // io_uring_queue_init.
+ struct io_uring* iu = nullptr;
+ if (thread_local_io_urings_) {
+ iu = static_cast<struct io_uring*>(thread_local_io_urings_->Get());
+ if (iu == nullptr) {
+ iu = CreateIOUring();
+ if (iu != nullptr) {
+ thread_local_io_urings_->Reset(iu);
+ }
+ }
+ }
+
+ // Init failed, platform doesn't support io_uring.
+ if (iu == nullptr) {
+ return IOStatus::NotSupported("ReadAsync");
+ }
+
+ // Allocate io_handle.
+ IOHandleDeleter deletefn = [](void* args) -> void {
+ delete (static_cast<Posix_IOHandle*>(args));
+ args = nullptr;
+ };
+
+ // Initialize Posix_IOHandle.
+ Posix_IOHandle* posix_handle =
+ new Posix_IOHandle(iu, cb, cb_arg, req.offset, req.len, req.scratch,
+ use_direct_io(), GetRequiredBufferAlignment());
+ posix_handle->iov.iov_base = req.scratch;
+ posix_handle->iov.iov_len = req.len;
+
+ *io_handle = static_cast<void*>(posix_handle);
+ *del_fn = deletefn;
+
+ // Step 3: io_uring_sqe_set_data
+ struct io_uring_sqe* sqe;
+ sqe = io_uring_get_sqe(iu);
+
+ io_uring_prep_readv(sqe, fd_, /*sqe->addr=*/&posix_handle->iov,
+ /*sqe->len=*/1, /*sqe->offset=*/posix_handle->offset);
+
+ // Sets sqe->user_data to posix_handle.
+ io_uring_sqe_set_data(sqe, posix_handle);
+
+ // Step 4: io_uring_submit
+ ssize_t ret = io_uring_submit(iu);
+ if (ret < 0) {
+ fprintf(stderr, "io_uring_submit error: %ld\n", long(ret));
+ return IOStatus::IOError("io_uring_submit() requested but returned " +
+ std::to_string(ret));
+ }
+ return IOStatus::OK();
+#else
+ (void)req;
+ (void)cb;
+ (void)cb_arg;
+ (void)io_handle;
+ (void)del_fn;
+ return IOStatus::NotSupported("ReadAsync");
+#endif
+}
+
+/*
+ * PosixMmapReadableFile
+ *
+ * mmap() based random-access
+ */
+// base[0,length-1] contains the mmapped contents of the file.
+PosixMmapReadableFile::PosixMmapReadableFile(const int fd,
+ const std::string& fname,
+ void* base, size_t length,
+ const EnvOptions& options)
+ : fd_(fd), filename_(fname), mmapped_region_(base), length_(length) {
+#ifdef NDEBUG
+ (void)options;
+#endif
+ fd_ = fd_ + 0; // suppress the warning for used variables
+ assert(options.use_mmap_reads);
+ assert(!options.use_direct_reads);
+}
+
+PosixMmapReadableFile::~PosixMmapReadableFile() {
+ int ret = munmap(mmapped_region_, length_);
+ if (ret != 0) {
+ fprintf(stdout, "failed to munmap %p length %" ROCKSDB_PRIszt " \n",
+ mmapped_region_, length_);
+ }
+ close(fd_);
+}
+
+IOStatus PosixMmapReadableFile::Read(uint64_t offset, size_t n,
+ const IOOptions& /*opts*/, Slice* result,
+ char* /*scratch*/,
+ IODebugContext* /*dbg*/) const {
+ IOStatus s;
+ if (offset > length_) {
+ *result = Slice();
+ return IOError("While mmap read offset " + std::to_string(offset) +
+ " larger than file length " + std::to_string(length_),
+ filename_, EINVAL);
+ } else if (offset + n > length_) {
+ n = static_cast<size_t>(length_ - offset);
+ }
+ *result = Slice(reinterpret_cast<char*>(mmapped_region_) + offset, n);
+ return s;
+}
+
+void PosixMmapReadableFile::Hint(AccessPattern pattern) {
+ switch (pattern) {
+ case kNormal:
+ Madvise(mmapped_region_, length_, POSIX_MADV_NORMAL);
+ break;
+ case kRandom:
+ Madvise(mmapped_region_, length_, POSIX_MADV_RANDOM);
+ break;
+ case kSequential:
+ Madvise(mmapped_region_, length_, POSIX_MADV_SEQUENTIAL);
+ break;
+ case kWillNeed:
+ Madvise(mmapped_region_, length_, POSIX_MADV_WILLNEED);
+ break;
+ case kWontNeed:
+ Madvise(mmapped_region_, length_, POSIX_MADV_DONTNEED);
+ break;
+ default:
+ assert(false);
+ break;
+ }
+}
+
+IOStatus PosixMmapReadableFile::InvalidateCache(size_t offset, size_t length) {
+#ifndef OS_LINUX
+ (void)offset;
+ (void)length;
+ return IOStatus::OK();
+#else
+ // free OS pages
+ int ret = Fadvise(fd_, offset, length, POSIX_FADV_DONTNEED);
+ if (ret == 0) {
+ return IOStatus::OK();
+ }
+ return IOError("While fadvise not needed. Offset " + std::to_string(offset) +
+ " len" + std::to_string(length),
+ filename_, errno);
+#endif
+}
+
+/*
+ * PosixMmapFile
+ *
+ * We preallocate up to an extra megabyte and use memcpy to append new
+ * data to the file. This is safe since we either properly close the
+ * file before reading from it, or for log files, the reading code
+ * knows enough to skip zero suffixes.
+ */
+IOStatus PosixMmapFile::UnmapCurrentRegion() {
+ TEST_KILL_RANDOM("PosixMmapFile::UnmapCurrentRegion:0");
+ if (base_ != nullptr) {
+ int munmap_status = munmap(base_, limit_ - base_);
+ if (munmap_status != 0) {
+ return IOError("While munmap", filename_, munmap_status);
+ }
+ file_offset_ += limit_ - base_;
+ base_ = nullptr;
+ limit_ = nullptr;
+ last_sync_ = nullptr;
+ dst_ = nullptr;
+
+ // Increase the amount we map the next time, but capped at 1MB
+ if (map_size_ < (1 << 20)) {
+ map_size_ *= 2;
+ }
+ }
+ return IOStatus::OK();
+}
+
+IOStatus PosixMmapFile::MapNewRegion() {
+#ifdef ROCKSDB_FALLOCATE_PRESENT
+ assert(base_ == nullptr);
+ TEST_KILL_RANDOM("PosixMmapFile::UnmapCurrentRegion:0");
+ // we can't fallocate with FALLOC_FL_KEEP_SIZE here
+ if (allow_fallocate_) {
+ IOSTATS_TIMER_GUARD(allocate_nanos);
+ int alloc_status = fallocate(fd_, 0, file_offset_, map_size_);
+ if (alloc_status != 0) {
+ // fallback to posix_fallocate
+ alloc_status = posix_fallocate(fd_, file_offset_, map_size_);
+ }
+ if (alloc_status != 0) {
+ return IOStatus::IOError("Error allocating space to file : " + filename_ +
+ "Error : " + errnoStr(alloc_status).c_str());
+ }
+ }
+
+ TEST_KILL_RANDOM("PosixMmapFile::Append:1");
+ void* ptr = mmap(nullptr, map_size_, PROT_READ | PROT_WRITE, MAP_SHARED, fd_,
+ file_offset_);
+ if (ptr == MAP_FAILED) {
+ return IOStatus::IOError("MMap failed on " + filename_);
+ }
+ TEST_KILL_RANDOM("PosixMmapFile::Append:2");
+
+ base_ = reinterpret_cast<char*>(ptr);
+ limit_ = base_ + map_size_;
+ dst_ = base_;
+ last_sync_ = base_;
+ return IOStatus::OK();
+#else
+ return IOStatus::NotSupported("This platform doesn't support fallocate()");
+#endif
+}
+
+IOStatus PosixMmapFile::Msync() {
+ if (dst_ == last_sync_) {
+ return IOStatus::OK();
+ }
+ // Find the beginnings of the pages that contain the first and last
+ // bytes to be synced.
+ size_t p1 = TruncateToPageBoundary(last_sync_ - base_);
+ size_t p2 = TruncateToPageBoundary(dst_ - base_ - 1);
+ last_sync_ = dst_;
+ TEST_KILL_RANDOM("PosixMmapFile::Msync:0");
+ if (msync(base_ + p1, p2 - p1 + page_size_, MS_SYNC) < 0) {
+ return IOError("While msync", filename_, errno);
+ }
+ return IOStatus::OK();
+}
+
+PosixMmapFile::PosixMmapFile(const std::string& fname, int fd, size_t page_size,
+ const EnvOptions& options)
+ : filename_(fname),
+ fd_(fd),
+ page_size_(page_size),
+ map_size_(Roundup(65536, page_size)),
+ base_(nullptr),
+ limit_(nullptr),
+ dst_(nullptr),
+ last_sync_(nullptr),
+ file_offset_(0) {
+#ifdef ROCKSDB_FALLOCATE_PRESENT
+ allow_fallocate_ = options.allow_fallocate;
+ fallocate_with_keep_size_ = options.fallocate_with_keep_size;
+#else
+ (void)options;
+#endif
+ assert((page_size & (page_size - 1)) == 0);
+ assert(options.use_mmap_writes);
+ assert(!options.use_direct_writes);
+}
+
+PosixMmapFile::~PosixMmapFile() {
+ if (fd_ >= 0) {
+ IOStatus s = PosixMmapFile::Close(IOOptions(), nullptr);
+ s.PermitUncheckedError();
+ }
+}
+
+IOStatus PosixMmapFile::Append(const Slice& data, const IOOptions& /*opts*/,
+ IODebugContext* /*dbg*/) {
+ const char* src = data.data();
+ size_t left = data.size();
+ while (left > 0) {
+ assert(base_ <= dst_);
+ assert(dst_ <= limit_);
+ size_t avail = limit_ - dst_;
+ if (avail == 0) {
+ IOStatus s = UnmapCurrentRegion();
+ if (!s.ok()) {
+ return s;
+ }
+ s = MapNewRegion();
+ if (!s.ok()) {
+ return s;
+ }
+ TEST_KILL_RANDOM("PosixMmapFile::Append:0");
+ }
+
+ size_t n = (left <= avail) ? left : avail;
+ assert(dst_);
+ memcpy(dst_, src, n);
+ dst_ += n;
+ src += n;
+ left -= n;
+ }
+ return IOStatus::OK();
+}
+
+IOStatus PosixMmapFile::Close(const IOOptions& /*opts*/,
+ IODebugContext* /*dbg*/) {
+ IOStatus s;
+ size_t unused = limit_ - dst_;
+
+ s = UnmapCurrentRegion();
+ if (!s.ok()) {
+ s = IOError("While closing mmapped file", filename_, errno);
+ } else if (unused > 0) {
+ // Trim the extra space at the end of the file
+ if (ftruncate(fd_, file_offset_ - unused) < 0) {
+ s = IOError("While ftruncating mmaped file", filename_, errno);
+ }
+ }
+
+ if (close(fd_) < 0) {
+ if (s.ok()) {
+ s = IOError("While closing mmapped file", filename_, errno);
+ }
+ }
+
+ fd_ = -1;
+ base_ = nullptr;
+ limit_ = nullptr;
+ return s;
+}
+
+IOStatus PosixMmapFile::Flush(const IOOptions& /*opts*/,
+ IODebugContext* /*dbg*/) {
+ return IOStatus::OK();
+}
+
+IOStatus PosixMmapFile::Sync(const IOOptions& /*opts*/,
+ IODebugContext* /*dbg*/) {
+#ifdef HAVE_FULLFSYNC
+ if (::fcntl(fd_, F_FULLFSYNC) < 0) {
+ return IOError("while fcntl(F_FULLSYNC) mmapped file", filename_, errno);
+ }
+#else // HAVE_FULLFSYNC
+ if (fdatasync(fd_) < 0) {
+ return IOError("While fdatasync mmapped file", filename_, errno);
+ }
+#endif // HAVE_FULLFSYNC
+
+ return Msync();
+}
+
+/**
+ * Flush data as well as metadata to stable storage.
+ */
+IOStatus PosixMmapFile::Fsync(const IOOptions& /*opts*/,
+ IODebugContext* /*dbg*/) {
+#ifdef HAVE_FULLFSYNC
+ if (::fcntl(fd_, F_FULLFSYNC) < 0) {
+ return IOError("While fcntl(F_FULLSYNC) on mmaped file", filename_, errno);
+ }
+#else // HAVE_FULLFSYNC
+ if (fsync(fd_) < 0) {
+ return IOError("While fsync mmaped file", filename_, errno);
+ }
+#endif // HAVE_FULLFSYNC
+
+ return Msync();
+}
+
+/**
+ * Get the size of valid data in the file. This will not match the
+ * size that is returned from the filesystem because we use mmap
+ * to extend file by map_size every time.
+ */
+uint64_t PosixMmapFile::GetFileSize(const IOOptions& /*opts*/,
+ IODebugContext* /*dbg*/) {
+ size_t used = dst_ - base_;
+ return file_offset_ + used;
+}
+
+IOStatus PosixMmapFile::InvalidateCache(size_t offset, size_t length) {
+#ifndef OS_LINUX
+ (void)offset;
+ (void)length;
+ return IOStatus::OK();
+#else
+ // free OS pages
+ int ret = Fadvise(fd_, offset, length, POSIX_FADV_DONTNEED);
+ if (ret == 0) {
+ return IOStatus::OK();
+ }
+ return IOError("While fadvise NotNeeded mmapped file", filename_, errno);
+#endif
+}
+
+#ifdef ROCKSDB_FALLOCATE_PRESENT
+IOStatus PosixMmapFile::Allocate(uint64_t offset, uint64_t len,
+ const IOOptions& /*opts*/,
+ IODebugContext* /*dbg*/) {
+ assert(offset <= static_cast<uint64_t>(std::numeric_limits<off_t>::max()));
+ assert(len <= static_cast<uint64_t>(std::numeric_limits<off_t>::max()));
+ TEST_KILL_RANDOM("PosixMmapFile::Allocate:0");
+ int alloc_status = 0;
+ if (allow_fallocate_) {
+ alloc_status =
+ fallocate(fd_, fallocate_with_keep_size_ ? FALLOC_FL_KEEP_SIZE : 0,
+ static_cast<off_t>(offset), static_cast<off_t>(len));
+ }
+ if (alloc_status == 0) {
+ return IOStatus::OK();
+ } else {
+ return IOError("While fallocate offset " + std::to_string(offset) +
+ " len " + std::to_string(len),
+ filename_, errno);
+ }
+}
+#endif
+
+/*
+ * PosixWritableFile
+ *
+ * Use posix write to write data to a file.
+ */
+PosixWritableFile::PosixWritableFile(const std::string& fname, int fd,
+ size_t logical_block_size,
+ const EnvOptions& options)
+ : FSWritableFile(options),
+ filename_(fname),
+ use_direct_io_(options.use_direct_writes),
+ fd_(fd),
+ filesize_(0),
+ logical_sector_size_(logical_block_size) {
+#ifdef ROCKSDB_FALLOCATE_PRESENT
+ allow_fallocate_ = options.allow_fallocate;
+ fallocate_with_keep_size_ = options.fallocate_with_keep_size;
+#endif
+#ifdef ROCKSDB_RANGESYNC_PRESENT
+ sync_file_range_supported_ = IsSyncFileRangeSupported(fd_);
+#endif // ROCKSDB_RANGESYNC_PRESENT
+ assert(!options.use_mmap_writes);
+}
+
+PosixWritableFile::~PosixWritableFile() {
+ if (fd_ >= 0) {
+ IOStatus s = PosixWritableFile::Close(IOOptions(), nullptr);
+ s.PermitUncheckedError();
+ }
+}
+
+IOStatus PosixWritableFile::Append(const Slice& data, const IOOptions& /*opts*/,
+ IODebugContext* /*dbg*/) {
+ if (use_direct_io()) {
+ assert(IsSectorAligned(data.size(), GetRequiredBufferAlignment()));
+ assert(IsSectorAligned(data.data(), GetRequiredBufferAlignment()));
+ }
+ const char* src = data.data();
+ size_t nbytes = data.size();
+
+ if (!PosixWrite(fd_, src, nbytes)) {
+ return IOError("While appending to file", filename_, errno);
+ }
+
+ filesize_ += nbytes;
+ return IOStatus::OK();
+}
+
+IOStatus PosixWritableFile::PositionedAppend(const Slice& data, uint64_t offset,
+ const IOOptions& /*opts*/,
+ IODebugContext* /*dbg*/) {
+ if (use_direct_io()) {
+ assert(IsSectorAligned(offset, GetRequiredBufferAlignment()));
+ assert(IsSectorAligned(data.size(), GetRequiredBufferAlignment()));
+ assert(IsSectorAligned(data.data(), GetRequiredBufferAlignment()));
+ }
+ assert(offset <= static_cast<uint64_t>(std::numeric_limits<off_t>::max()));
+ const char* src = data.data();
+ size_t nbytes = data.size();
+ if (!PosixPositionedWrite(fd_, src, nbytes, static_cast<off_t>(offset))) {
+ return IOError("While pwrite to file at offset " + std::to_string(offset),
+ filename_, errno);
+ }
+ filesize_ = offset + nbytes;
+ return IOStatus::OK();
+}
+
+IOStatus PosixWritableFile::Truncate(uint64_t size, const IOOptions& /*opts*/,
+ IODebugContext* /*dbg*/) {
+ IOStatus s;
+ int r = ftruncate(fd_, size);
+ if (r < 0) {
+ s = IOError("While ftruncate file to size " + std::to_string(size),
+ filename_, errno);
+ } else {
+ filesize_ = size;
+ }
+ return s;
+}
+
+IOStatus PosixWritableFile::Close(const IOOptions& /*opts*/,
+ IODebugContext* /*dbg*/) {
+ IOStatus s;
+
+ size_t block_size;
+ size_t last_allocated_block;
+ GetPreallocationStatus(&block_size, &last_allocated_block);
+ TEST_SYNC_POINT_CALLBACK("PosixWritableFile::Close", &last_allocated_block);
+ if (last_allocated_block > 0) {
+ // trim the extra space preallocated at the end of the file
+ // NOTE(ljin): we probably don't want to surface failure as an IOError,
+ // but it will be nice to log these errors.
+ int dummy __attribute__((__unused__));
+ dummy = ftruncate(fd_, filesize_);
+#if defined(ROCKSDB_FALLOCATE_PRESENT) && defined(FALLOC_FL_PUNCH_HOLE)
+ // in some file systems, ftruncate only trims trailing space if the
+ // new file size is smaller than the current size. Calling fallocate
+ // with FALLOC_FL_PUNCH_HOLE flag to explicitly release these unused
+ // blocks. FALLOC_FL_PUNCH_HOLE is supported on at least the following
+ // filesystems:
+ // XFS (since Linux 2.6.38)
+ // ext4 (since Linux 3.0)
+ // Btrfs (since Linux 3.7)
+ // tmpfs (since Linux 3.5)
+ // We ignore error since failure of this operation does not affect
+ // correctness.
+ struct stat file_stats;
+ int result = fstat(fd_, &file_stats);
+ // After ftruncate, we check whether ftruncate has the correct behavior.
+ // If not, we should hack it with FALLOC_FL_PUNCH_HOLE
+ if (result == 0 &&
+ (file_stats.st_size + file_stats.st_blksize - 1) /
+ file_stats.st_blksize !=
+ file_stats.st_blocks / (file_stats.st_blksize / 512)) {
+ IOSTATS_TIMER_GUARD(allocate_nanos);
+ if (allow_fallocate_) {
+ fallocate(fd_, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE, filesize_,
+ block_size * last_allocated_block - filesize_);
+ }
+ }
+#endif
+ }
+
+ if (close(fd_) < 0) {
+ s = IOError("While closing file after writing", filename_, errno);
+ }
+ fd_ = -1;
+ return s;
+}
+
+// write out the cached data to the OS cache
+IOStatus PosixWritableFile::Flush(const IOOptions& /*opts*/,
+ IODebugContext* /*dbg*/) {
+ return IOStatus::OK();
+}
+
+IOStatus PosixWritableFile::Sync(const IOOptions& /*opts*/,
+ IODebugContext* /*dbg*/) {
+#ifdef HAVE_FULLFSYNC
+ if (::fcntl(fd_, F_FULLFSYNC) < 0) {
+ return IOError("while fcntl(F_FULLFSYNC)", filename_, errno);
+ }
+#else // HAVE_FULLFSYNC
+ if (fdatasync(fd_) < 0) {
+ return IOError("While fdatasync", filename_, errno);
+ }
+#endif // HAVE_FULLFSYNC
+ return IOStatus::OK();
+}
+
+IOStatus PosixWritableFile::Fsync(const IOOptions& /*opts*/,
+ IODebugContext* /*dbg*/) {
+#ifdef HAVE_FULLFSYNC
+ if (::fcntl(fd_, F_FULLFSYNC) < 0) {
+ return IOError("while fcntl(F_FULLFSYNC)", filename_, errno);
+ }
+#else // HAVE_FULLFSYNC
+ if (fsync(fd_) < 0) {
+ return IOError("While fsync", filename_, errno);
+ }
+#endif // HAVE_FULLFSYNC
+ return IOStatus::OK();
+}
+
+bool PosixWritableFile::IsSyncThreadSafe() const { return true; }
+
+uint64_t PosixWritableFile::GetFileSize(const IOOptions& /*opts*/,
+ IODebugContext* /*dbg*/) {
+ return filesize_;
+}
+
+void PosixWritableFile::SetWriteLifeTimeHint(Env::WriteLifeTimeHint hint) {
+#ifdef OS_LINUX
+// Suppress Valgrind "Unimplemented functionality" error.
+#ifndef ROCKSDB_VALGRIND_RUN
+ if (hint == write_hint_) {
+ return;
+ }
+ if (fcntl(fd_, F_SET_RW_HINT, &hint) == 0) {
+ write_hint_ = hint;
+ }
+#else
+ (void)hint;
+#endif // ROCKSDB_VALGRIND_RUN
+#else
+ (void)hint;
+#endif // OS_LINUX
+}
+
+IOStatus PosixWritableFile::InvalidateCache(size_t offset, size_t length) {
+ if (use_direct_io()) {
+ return IOStatus::OK();
+ }
+#ifndef OS_LINUX
+ (void)offset;
+ (void)length;
+ return IOStatus::OK();
+#else
+ // free OS pages
+ int ret = Fadvise(fd_, offset, length, POSIX_FADV_DONTNEED);
+ if (ret == 0) {
+ return IOStatus::OK();
+ }
+ return IOError("While fadvise NotNeeded", filename_, errno);
+#endif
+}
+
+#ifdef ROCKSDB_FALLOCATE_PRESENT
+IOStatus PosixWritableFile::Allocate(uint64_t offset, uint64_t len,
+ const IOOptions& /*opts*/,
+ IODebugContext* /*dbg*/) {
+ assert(offset <= static_cast<uint64_t>(std::numeric_limits<off_t>::max()));
+ assert(len <= static_cast<uint64_t>(std::numeric_limits<off_t>::max()));
+ TEST_KILL_RANDOM("PosixWritableFile::Allocate:0");
+ IOSTATS_TIMER_GUARD(allocate_nanos);
+ int alloc_status = 0;
+ if (allow_fallocate_) {
+ alloc_status =
+ fallocate(fd_, fallocate_with_keep_size_ ? FALLOC_FL_KEEP_SIZE : 0,
+ static_cast<off_t>(offset), static_cast<off_t>(len));
+ }
+ if (alloc_status == 0) {
+ return IOStatus::OK();
+ } else {
+ return IOError("While fallocate offset " + std::to_string(offset) +
+ " len " + std::to_string(len),
+ filename_, errno);
+ }
+}
+#endif
+
+IOStatus PosixWritableFile::RangeSync(uint64_t offset, uint64_t nbytes,
+ const IOOptions& opts,
+ IODebugContext* dbg) {
+#ifdef ROCKSDB_RANGESYNC_PRESENT
+ assert(offset <= static_cast<uint64_t>(std::numeric_limits<off_t>::max()));
+ assert(nbytes <= static_cast<uint64_t>(std::numeric_limits<off_t>::max()));
+ if (sync_file_range_supported_) {
+ int ret;
+ if (strict_bytes_per_sync_) {
+ // Specifying `SYNC_FILE_RANGE_WAIT_BEFORE` together with an offset/length
+ // that spans all bytes written so far tells `sync_file_range` to wait for
+ // any outstanding writeback requests to finish before issuing a new one.
+ ret =
+ sync_file_range(fd_, 0, static_cast<off_t>(offset + nbytes),
+ SYNC_FILE_RANGE_WAIT_BEFORE | SYNC_FILE_RANGE_WRITE);
+ } else {
+ ret = sync_file_range(fd_, static_cast<off_t>(offset),
+ static_cast<off_t>(nbytes), SYNC_FILE_RANGE_WRITE);
+ }
+ if (ret != 0) {
+ return IOError("While sync_file_range returned " + std::to_string(ret),
+ filename_, errno);
+ }
+ return IOStatus::OK();
+ }
+#endif // ROCKSDB_RANGESYNC_PRESENT
+ return FSWritableFile::RangeSync(offset, nbytes, opts, dbg);
+}
+
+#ifdef OS_LINUX
+size_t PosixWritableFile::GetUniqueId(char* id, size_t max_size) const {
+ return PosixHelper::GetUniqueIdFromFile(fd_, id, max_size);
+}
+#endif
+
+/*
+ * PosixRandomRWFile
+ */
+
+PosixRandomRWFile::PosixRandomRWFile(const std::string& fname, int fd,
+ const EnvOptions& /*options*/)
+ : filename_(fname), fd_(fd) {}
+
+PosixRandomRWFile::~PosixRandomRWFile() {
+ if (fd_ >= 0) {
+ IOStatus s = Close(IOOptions(), nullptr);
+ s.PermitUncheckedError();
+ }
+}
+
+IOStatus PosixRandomRWFile::Write(uint64_t offset, const Slice& data,
+ const IOOptions& /*opts*/,
+ IODebugContext* /*dbg*/) {
+ const char* src = data.data();
+ size_t nbytes = data.size();
+ if (!PosixPositionedWrite(fd_, src, nbytes, static_cast<off_t>(offset))) {
+ return IOError("While write random read/write file at offset " +
+ std::to_string(offset),
+ filename_, errno);
+ }
+
+ return IOStatus::OK();
+}
+
+IOStatus PosixRandomRWFile::Read(uint64_t offset, size_t n,
+ const IOOptions& /*opts*/, Slice* result,
+ char* scratch, IODebugContext* /*dbg*/) const {
+ size_t left = n;
+ char* ptr = scratch;
+ while (left > 0) {
+ ssize_t done = pread(fd_, ptr, left, offset);
+ if (done < 0) {
+ // error while reading from file
+ if (errno == EINTR) {
+ // read was interrupted, try again.
+ continue;
+ }
+ return IOError("While reading random read/write file offset " +
+ std::to_string(offset) + " len " + std::to_string(n),
+ filename_, errno);
+ } else if (done == 0) {
+ // Nothing more to read
+ break;
+ }
+
+ // Read `done` bytes
+ ptr += done;
+ offset += done;
+ left -= done;
+ }
+
+ *result = Slice(scratch, n - left);
+ return IOStatus::OK();
+}
+
+IOStatus PosixRandomRWFile::Flush(const IOOptions& /*opts*/,
+ IODebugContext* /*dbg*/) {
+ return IOStatus::OK();
+}
+
+IOStatus PosixRandomRWFile::Sync(const IOOptions& /*opts*/,
+ IODebugContext* /*dbg*/) {
+#ifdef HAVE_FULLFSYNC
+ if (::fcntl(fd_, F_FULLFSYNC) < 0) {
+ return IOError("while fcntl(F_FULLFSYNC) random rw file", filename_, errno);
+ }
+#else // HAVE_FULLFSYNC
+ if (fdatasync(fd_) < 0) {
+ return IOError("While fdatasync random read/write file", filename_, errno);
+ }
+#endif // HAVE_FULLFSYNC
+ return IOStatus::OK();
+}
+
+IOStatus PosixRandomRWFile::Fsync(const IOOptions& /*opts*/,
+ IODebugContext* /*dbg*/) {
+#ifdef HAVE_FULLFSYNC
+ if (::fcntl(fd_, F_FULLFSYNC) < 0) {
+ return IOError("While fcntl(F_FULLSYNC) random rw file", filename_, errno);
+ }
+#else // HAVE_FULLFSYNC
+ if (fsync(fd_) < 0) {
+ return IOError("While fsync random read/write file", filename_, errno);
+ }
+#endif // HAVE_FULLFSYNC
+ return IOStatus::OK();
+}
+
+IOStatus PosixRandomRWFile::Close(const IOOptions& /*opts*/,
+ IODebugContext* /*dbg*/) {
+ if (close(fd_) < 0) {
+ return IOError("While close random read/write file", filename_, errno);
+ }
+ fd_ = -1;
+ return IOStatus::OK();
+}
+
+PosixMemoryMappedFileBuffer::~PosixMemoryMappedFileBuffer() {
+ // TODO should have error handling though not much we can do...
+ munmap(this->base_, length_);
+}
+
+/*
+ * PosixDirectory
+ */
+#if !defined(BTRFS_SUPER_MAGIC)
+// The magic number for BTRFS is fixed, if it's not defined, define it here
+#define BTRFS_SUPER_MAGIC 0x9123683E
+#endif
+PosixDirectory::PosixDirectory(int fd, const std::string& directory_name)
+ : fd_(fd), directory_name_(directory_name) {
+ is_btrfs_ = false;
+#ifdef OS_LINUX
+ struct statfs buf;
+ int ret = fstatfs(fd, &buf);
+ is_btrfs_ = (ret == 0 && buf.f_type == static_cast<decltype(buf.f_type)>(
+ BTRFS_SUPER_MAGIC));
+#endif
+}
+
+PosixDirectory::~PosixDirectory() {
+ if (fd_ >= 0) {
+ IOStatus s = PosixDirectory::Close(IOOptions(), nullptr);
+ s.PermitUncheckedError();
+ }
+}
+
+IOStatus PosixDirectory::Fsync(const IOOptions& opts, IODebugContext* dbg) {
+ return FsyncWithDirOptions(opts, dbg, DirFsyncOptions());
+}
+
+// Users who want the file entries synced in Directory project must call a
+// Fsync or FsyncWithDirOptions function before Close
+IOStatus PosixDirectory::Close(const IOOptions& /*opts*/,
+ IODebugContext* /*dbg*/) {
+ IOStatus s = IOStatus::OK();
+ if (close(fd_) < 0) {
+ s = IOError("While closing directory ", directory_name_, errno);
+ } else {
+ fd_ = -1;
+ }
+ return s;
+}
+
+IOStatus PosixDirectory::FsyncWithDirOptions(
+ const IOOptions& /*opts*/, IODebugContext* /*dbg*/,
+ const DirFsyncOptions& dir_fsync_options) {
+ assert(fd_ >= 0); // Check use after close
+ IOStatus s = IOStatus::OK();
+#ifndef OS_AIX
+ if (is_btrfs_) {
+ // skip dir fsync for new file creation, which is not needed for btrfs
+ if (dir_fsync_options.reason == DirFsyncOptions::kNewFileSynced) {
+ return s;
+ }
+ // skip dir fsync for renaming file, only need to sync new file
+ if (dir_fsync_options.reason == DirFsyncOptions::kFileRenamed) {
+ std::string new_name = dir_fsync_options.renamed_new_name;
+ assert(!new_name.empty());
+ int fd;
+ do {
+ IOSTATS_TIMER_GUARD(open_nanos);
+ fd = open(new_name.c_str(), O_RDONLY);
+ } while (fd < 0 && errno == EINTR);
+ if (fd < 0) {
+ s = IOError("While open renaming file", new_name, errno);
+ } else if (fsync(fd) < 0) {
+ s = IOError("While fsync renaming file", new_name, errno);
+ }
+ if (close(fd) < 0) {
+ s = IOError("While closing file after fsync", new_name, errno);
+ }
+ return s;
+ }
+ // fallback to dir-fsync for kDefault, kDirRenamed and kFileDeleted
+ }
+
+ // skip fsync/fcntl when fd_ == -1 since this file descriptor has been closed
+ // in either the de-construction or the close function, data must have been
+ // fsync-ed before de-construction and close is called
+#ifdef HAVE_FULLFSYNC
+ // btrfs is a Linux file system, while currently F_FULLFSYNC is available on
+ // Mac OS.
+ assert(!is_btrfs_);
+ if (fd_ != -1 && ::fcntl(fd_, F_FULLFSYNC) < 0) {
+ return IOError("while fcntl(F_FULLFSYNC)", "a directory", errno);
+ }
+#else // HAVE_FULLFSYNC
+ if (fd_ != -1 && fsync(fd_) == -1) {
+ s = IOError("While fsync", "a directory", errno);
+ }
+#endif // HAVE_FULLFSYNC
+#endif // OS_AIX
+ return s;
+}
+} // namespace ROCKSDB_NAMESPACE
+#endif