--- /dev/null
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+/*
+ * Ceph - scalable distributed file system
+ *
+ * Copyright (C) 2004-2006 Sage Weil <sage@newdream.net>
+ *
+ * This is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License version 2.1, as published by the Free Software
+ * Foundation. See file COPYING.
+ *
+ */
+
+#include "include/int_types.h"
+#include "include/types.h"
+
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/ioctl.h>
+#include "include/compat.h"
+#include "include/linux_fiemap.h"
+#include "include/color.h"
+#include "include/buffer.h"
+#include "include/assert.h"
+
+#ifndef __CYGWIN__
+#include "os/fs/btrfs_ioctl.h"
+#endif
+
+#include <iostream>
+#include <fstream>
+#include <sstream>
+
+#include "BtrfsFileStoreBackend.h"
+
+#include "common/errno.h"
+#include "common/config.h"
+
+#if defined(__linux__)
+
+#define dout_context cct()
+#define dout_subsys ceph_subsys_filestore
+#undef dout_prefix
+#define dout_prefix *_dout << "btrfsfilestorebackend(" << get_basedir_path() << ") "
+
+#define ALIGN_DOWN(x, by) ((x) - ((x) % (by)))
+#define ALIGNED(x, by) (!((x) % (by)))
+#define ALIGN_UP(x, by) (ALIGNED((x), (by)) ? (x) : (ALIGN_DOWN((x), (by)) + (by)))
+
+BtrfsFileStoreBackend::BtrfsFileStoreBackend(FileStore *fs):
+ GenericFileStoreBackend(fs), has_clone_range(false),
+ has_snap_create(false), has_snap_destroy(false),
+ has_snap_create_v2(false), has_wait_sync(false), stable_commits(false),
+ m_filestore_btrfs_clone_range(cct()->_conf->filestore_btrfs_clone_range),
+ m_filestore_btrfs_snap (cct()->_conf->filestore_btrfs_snap) { }
+
+int BtrfsFileStoreBackend::detect_features()
+{
+ int r;
+
+ r = GenericFileStoreBackend::detect_features();
+ if (r < 0)
+ return r;
+
+ // clone_range?
+ if (m_filestore_btrfs_clone_range) {
+ int fd = ::openat(get_basedir_fd(), "clone_range_test", O_CREAT|O_WRONLY, 0600);
+ if (fd >= 0) {
+ if (::unlinkat(get_basedir_fd(), "clone_range_test", 0) < 0) {
+ r = -errno;
+ dout(0) << "detect_feature: failed to unlink test file for CLONE_RANGE ioctl: "
+ << cpp_strerror(r) << dendl;
+ }
+ btrfs_ioctl_clone_range_args clone_args;
+ memset(&clone_args, 0, sizeof(clone_args));
+ clone_args.src_fd = -1;
+ r = ::ioctl(fd, BTRFS_IOC_CLONE_RANGE, &clone_args);
+ if (r < 0 && errno == EBADF) {
+ dout(0) << "detect_feature: CLONE_RANGE ioctl is supported" << dendl;
+ has_clone_range = true;
+ } else {
+ r = -errno;
+ dout(0) << "detect_feature: CLONE_RANGE ioctl is NOT supported: " << cpp_strerror(r) << dendl;
+ }
+ TEMP_FAILURE_RETRY(::close(fd));
+ } else {
+ r = -errno;
+ dout(0) << "detect_feature: failed to create test file for CLONE_RANGE ioctl: "
+ << cpp_strerror(r) << dendl;
+ }
+ } else {
+ dout(0) << "detect_feature: CLONE_RANGE ioctl is DISABLED via 'filestore btrfs clone range' option" << dendl;
+ }
+
+ struct btrfs_ioctl_vol_args vol_args;
+ memset(&vol_args, 0, sizeof(vol_args));
+
+ // create test source volume
+ vol_args.fd = 0;
+ strcpy(vol_args.name, "test_subvol");
+ r = ::ioctl(get_basedir_fd(), BTRFS_IOC_SUBVOL_CREATE, &vol_args);
+ if (r != 0) {
+ r = -errno;
+ dout(0) << "detect_feature: failed to create simple subvolume " << vol_args.name << ": " << cpp_strerror(r) << dendl;
+ }
+ int srcfd = ::openat(get_basedir_fd(), vol_args.name, O_RDONLY);
+ if (srcfd < 0) {
+ r = -errno;
+ dout(0) << "detect_feature: failed to open " << vol_args.name << ": " << cpp_strerror(r) << dendl;
+ }
+
+ // snap_create and snap_destroy?
+ vol_args.fd = srcfd;
+ strcpy(vol_args.name, "sync_snap_test");
+ r = ::ioctl(get_basedir_fd(), BTRFS_IOC_SNAP_CREATE, &vol_args);
+ int err = errno;
+ if (r == 0 || errno == EEXIST) {
+ dout(0) << "detect_feature: SNAP_CREATE is supported" << dendl;
+ has_snap_create = true;
+
+ r = ::ioctl(get_basedir_fd(), BTRFS_IOC_SNAP_DESTROY, &vol_args);
+ if (r == 0) {
+ dout(0) << "detect_feature: SNAP_DESTROY is supported" << dendl;
+ has_snap_destroy = true;
+ } else {
+ err = -errno;
+ dout(0) << "detect_feature: SNAP_DESTROY failed: " << cpp_strerror(err) << dendl;
+
+ if (err == -EPERM && getuid() != 0) {
+ dout(0) << "detect_feature: failed with EPERM as non-root; remount with -o user_subvol_rm_allowed" << dendl;
+ cerr << TEXT_YELLOW
+ << "btrfs SNAP_DESTROY failed as non-root; remount with -o user_subvol_rm_allowed"
+ << TEXT_NORMAL << std::endl;
+ } else if (err == -EOPNOTSUPP) {
+ derr << "btrfs SNAP_DESTROY ioctl not supported; you need a kernel newer than 2.6.32" << dendl;
+ }
+ }
+ } else {
+ dout(0) << "detect_feature: SNAP_CREATE failed: " << cpp_strerror(err) << dendl;
+ }
+
+ if (m_filestore_btrfs_snap) {
+ if (has_snap_destroy)
+ stable_commits = true;
+ else
+ dout(0) << "detect_feature: snaps enabled, but no SNAP_DESTROY ioctl; DISABLING" << dendl;
+ }
+
+ // start_sync?
+ __u64 transid = 0;
+ r = ::ioctl(get_basedir_fd(), BTRFS_IOC_START_SYNC, &transid);
+ if (r < 0) {
+ int err = errno;
+ dout(0) << "detect_feature: START_SYNC got " << cpp_strerror(err) << dendl;
+ }
+ if (r == 0 && transid > 0) {
+ dout(0) << "detect_feature: START_SYNC is supported (transid " << transid << ")" << dendl;
+
+ // do we have wait_sync too?
+ r = ::ioctl(get_basedir_fd(), BTRFS_IOC_WAIT_SYNC, &transid);
+ if (r == 0 || errno == ERANGE) {
+ dout(0) << "detect_feature: WAIT_SYNC is supported" << dendl;
+ has_wait_sync = true;
+ } else {
+ int err = errno;
+ dout(0) << "detect_feature: WAIT_SYNC is NOT supported: " << cpp_strerror(err) << dendl;
+ }
+ } else {
+ int err = errno;
+ dout(0) << "detect_feature: START_SYNC is NOT supported: " << cpp_strerror(err) << dendl;
+ }
+
+ if (has_wait_sync) {
+ // async snap creation?
+ struct btrfs_ioctl_vol_args_v2 async_args;
+ memset(&async_args, 0, sizeof(async_args));
+ async_args.fd = srcfd;
+ async_args.flags = BTRFS_SUBVOL_CREATE_ASYNC;
+ strcpy(async_args.name, "async_snap_test");
+
+ // remove old one, first
+ struct stat st;
+ strcpy(vol_args.name, async_args.name);
+ if (::fstatat(get_basedir_fd(), vol_args.name, &st, 0) == 0) {
+ dout(0) << "detect_feature: removing old async_snap_test" << dendl;
+ r = ::ioctl(get_basedir_fd(), BTRFS_IOC_SNAP_DESTROY, &vol_args);
+ if (r != 0) {
+ int err = errno;
+ dout(0) << "detect_feature: failed to remove old async_snap_test: " << cpp_strerror(err) << dendl;
+ }
+ }
+
+ r = ::ioctl(get_basedir_fd(), BTRFS_IOC_SNAP_CREATE_V2, &async_args);
+ if (r == 0 || errno == EEXIST) {
+ dout(0) << "detect_feature: SNAP_CREATE_V2 is supported" << dendl;
+ has_snap_create_v2 = true;
+
+ // clean up
+ strcpy(vol_args.name, "async_snap_test");
+ r = ::ioctl(get_basedir_fd(), BTRFS_IOC_SNAP_DESTROY, &vol_args);
+ if (r != 0) {
+ int err = errno;
+ dout(0) << "detect_feature: SNAP_DESTROY failed: " << cpp_strerror(err) << dendl;
+ }
+ } else {
+ int err = errno;
+ dout(0) << "detect_feature: SNAP_CREATE_V2 is NOT supported: " << cpp_strerror(err) << dendl;
+ }
+ }
+
+ // clean up test subvol
+ if (srcfd >= 0)
+ TEMP_FAILURE_RETRY(::close(srcfd));
+
+ strcpy(vol_args.name, "test_subvol");
+ r = ::ioctl(get_basedir_fd(), BTRFS_IOC_SNAP_DESTROY, &vol_args);
+ if (r < 0) {
+ r = -errno;
+ dout(0) << "detect_feature: failed to remove " << vol_args.name << ": " << cpp_strerror(r) << dendl;
+ }
+
+ if (m_filestore_btrfs_snap && !has_snap_create_v2) {
+ dout(0) << "mount WARNING: btrfs snaps enabled, but no SNAP_CREATE_V2 ioctl (from kernel 2.6.37+)" << dendl;
+ cerr << TEXT_YELLOW
+ << " ** WARNING: 'filestore btrfs snap' is enabled (for safe transactions,\n"
+ << " rollback), but btrfs does not support the SNAP_CREATE_V2 ioctl\n"
+ << " (added in Linux 2.6.37). Expect slow btrfs sync/commit\n"
+ << " performance.\n"
+ << TEXT_NORMAL;
+ }
+
+ return 0;
+}
+
+bool BtrfsFileStoreBackend::can_checkpoint()
+{
+ return stable_commits;
+}
+
+int BtrfsFileStoreBackend::create_current()
+{
+ struct stat st;
+ int ret = ::stat(get_current_path().c_str(), &st);
+ if (ret == 0) {
+ // current/ exists
+ if (!S_ISDIR(st.st_mode)) {
+ dout(0) << "create_current: current/ exists but is not a directory" << dendl;
+ return -EINVAL;
+ }
+
+ struct stat basest;
+ struct statfs currentfs;
+ ret = ::fstat(get_basedir_fd(), &basest);
+ if (ret < 0) {
+ ret = -errno;
+ dout(0) << "create_current: cannot fstat basedir " << cpp_strerror(ret) << dendl;
+ return ret;
+ }
+ ret = ::statfs(get_current_path().c_str(), ¤tfs);
+ if (ret < 0) {
+ ret = -errno;
+ dout(0) << "create_current: cannot statsf basedir " << cpp_strerror(ret) << dendl;
+ return ret;
+ }
+ if (currentfs.f_type == BTRFS_SUPER_MAGIC && basest.st_dev != st.st_dev) {
+ dout(2) << "create_current: current appears to be a btrfs subvolume" << dendl;
+ stable_commits = true;
+ }
+ return 0;
+ }
+
+ struct btrfs_ioctl_vol_args volargs;
+ memset(&volargs, 0, sizeof(volargs));
+
+ volargs.fd = 0;
+ strcpy(volargs.name, "current");
+ if (::ioctl(get_basedir_fd(), BTRFS_IOC_SUBVOL_CREATE, (unsigned long int)&volargs) < 0) {
+ ret = -errno;
+ dout(0) << "create_current: BTRFS_IOC_SUBVOL_CREATE failed with error "
+ << cpp_strerror(ret) << dendl;
+ return ret;
+ }
+
+ dout(2) << "create_current: created btrfs subvol " << get_current_path() << dendl;
+ if (::chmod(get_current_path().c_str(), 0755) < 0) {
+ ret = -errno;
+ dout(0) << "create_current: failed to chmod " << get_current_path() << " to 0755: "
+ << cpp_strerror(ret) << dendl;
+ return ret;
+ }
+
+ stable_commits = true;
+ return 0;
+}
+
+int BtrfsFileStoreBackend::list_checkpoints(list<string>& ls)
+{
+ int ret, err = 0;
+
+ struct stat basest;
+ ret = ::fstat(get_basedir_fd(), &basest);
+ if (ret < 0) {
+ ret = -errno;
+ dout(0) << "list_checkpoints: cannot fstat basedir " << cpp_strerror(ret) << dendl;
+ return ret;
+ }
+
+ // get snap list
+ DIR *dir = ::opendir(get_basedir_path().c_str());
+ if (!dir) {
+ ret = -errno;
+ dout(0) << "list_checkpoints: opendir '" << get_basedir_path() << "' failed: "
+ << cpp_strerror(ret) << dendl;
+ return ret;
+ }
+
+ list<string> snaps;
+ char path[PATH_MAX];
+ struct dirent *de;
+ while ((de = ::readdir(dir))) {
+ snprintf(path, sizeof(path), "%s/%s", get_basedir_path().c_str(), de->d_name);
+
+ struct stat st;
+ ret = ::stat(path, &st);
+ if (ret < 0) {
+ err = -errno;
+ dout(0) << "list_checkpoints: stat '" << path << "' failed: "
+ << cpp_strerror(err) << dendl;
+ break;
+ }
+
+ if (!S_ISDIR(st.st_mode))
+ continue;
+
+ struct statfs fs;
+ ret = ::statfs(path, &fs);
+ if (ret < 0) {
+ err = -errno;
+ dout(0) << "list_checkpoints: statfs '" << path << "' failed: "
+ << cpp_strerror(err) << dendl;
+ break;
+ }
+
+ if (fs.f_type == BTRFS_SUPER_MAGIC && basest.st_dev != st.st_dev)
+ snaps.push_back(string(de->d_name));
+ }
+
+ if (::closedir(dir) < 0) {
+ ret = -errno;
+ dout(0) << "list_checkpoints: closedir failed: " << cpp_strerror(ret) << dendl;
+ if (!err)
+ err = ret;
+ }
+
+ if (err)
+ return err;
+
+ ls.swap(snaps);
+ return 0;
+}
+
+int BtrfsFileStoreBackend::create_checkpoint(const string& name, uint64_t *transid)
+{
+ dout(10) << "create_checkpoint: '" << name << "'" << dendl;
+ if (has_snap_create_v2 && transid) {
+ struct btrfs_ioctl_vol_args_v2 async_args;
+ memset(&async_args, 0, sizeof(async_args));
+ async_args.fd = get_current_fd();
+ async_args.flags = BTRFS_SUBVOL_CREATE_ASYNC;
+
+ size_t name_size = sizeof(async_args.name);
+ strncpy(async_args.name, name.c_str(), name_size);
+ async_args.name[name_size-1] = '\0';
+
+ int r = ::ioctl(get_basedir_fd(), BTRFS_IOC_SNAP_CREATE_V2, &async_args);
+ if (r < 0) {
+ r = -errno;
+ dout(0) << "create_checkpoint: async snap create '" << name << "' got " << cpp_strerror(r) << dendl;
+ return r;
+ }
+ dout(20) << "create_checkpoint: async snap create '" << name << "' transid " << async_args.transid << dendl;
+ *transid = async_args.transid;
+ } else {
+ struct btrfs_ioctl_vol_args vol_args;
+ memset(&vol_args, 0, sizeof(vol_args));
+ vol_args.fd = get_current_fd();
+
+ size_t name_size = sizeof(vol_args.name);
+ strncpy(vol_args.name, name.c_str(), name_size);
+ vol_args.name[name_size-1] = '\0';
+
+ int r = ::ioctl(get_basedir_fd(), BTRFS_IOC_SNAP_CREATE, &vol_args);
+ if (r < 0) {
+ r = -errno;
+ dout(0) << "create_checkpoint: snap create '" << name << "' got " << cpp_strerror(r) << dendl;
+ return r;
+ }
+ if (transid)
+ *transid = 0;
+ }
+ return 0;
+}
+
+int BtrfsFileStoreBackend::sync_checkpoint(uint64_t transid)
+{
+ // wait for commit
+ dout(10) << "sync_checkpoint: transid " << transid << " to complete" << dendl;
+ int ret = ::ioctl(get_op_fd(), BTRFS_IOC_WAIT_SYNC, &transid);
+ if (ret < 0) {
+ ret = -errno;
+ dout(0) << "sync_checkpoint: ioctl WAIT_SYNC got " << cpp_strerror(ret) << dendl;
+ return -errno;
+ }
+ dout(20) << "sync_checkpoint: done waiting for transid " << transid << dendl;
+ return 0;
+}
+
+int BtrfsFileStoreBackend::rollback_to(const string& name)
+{
+ dout(10) << "rollback_to: to '" << name << "'" << dendl;
+ char s[PATH_MAX];
+ btrfs_ioctl_vol_args vol_args;
+
+ memset(&vol_args, 0, sizeof(vol_args));
+ vol_args.fd = 0;
+ strcpy(vol_args.name, "current");
+
+ int ret = ::ioctl(get_basedir_fd(), BTRFS_IOC_SNAP_DESTROY, &vol_args);
+ if (ret && errno != ENOENT) {
+ dout(0) << "rollback_to: error removing old current subvol: " << cpp_strerror(ret) << dendl;
+ snprintf(s, sizeof(s), "%s/current.remove.me.%d", get_basedir_path().c_str(), rand());
+ if (::rename(get_current_path().c_str(), s)) {
+ ret = -errno;
+ dout(0) << "rollback_to: error renaming old current subvol: "
+ << cpp_strerror(ret) << dendl;
+ return ret;
+ }
+ }
+
+ snprintf(s, sizeof(s), "%s/%s", get_basedir_path().c_str(), name.c_str());
+
+ // roll back
+ vol_args.fd = ::open(s, O_RDONLY);
+ if (vol_args.fd < 0) {
+ ret = -errno;
+ dout(0) << "rollback_to: error opening '" << s << "': " << cpp_strerror(ret) << dendl;
+ return ret;
+ }
+ ret = ::ioctl(get_basedir_fd(), BTRFS_IOC_SNAP_CREATE, &vol_args);
+ if (ret < 0 ) {
+ ret = -errno;
+ dout(0) << "rollback_to: ioctl SNAP_CREATE got " << cpp_strerror(ret) << dendl;
+ }
+ TEMP_FAILURE_RETRY(::close(vol_args.fd));
+ return ret;
+}
+
+int BtrfsFileStoreBackend::destroy_checkpoint(const string& name)
+{
+ dout(10) << "destroy_checkpoint: '" << name << "'" << dendl;
+ btrfs_ioctl_vol_args vol_args;
+ memset(&vol_args, 0, sizeof(vol_args));
+ vol_args.fd = 0;
+ strncpy(vol_args.name, name.c_str(), sizeof(vol_args.name));
+
+ int ret = ::ioctl(get_basedir_fd(), BTRFS_IOC_SNAP_DESTROY, &vol_args);
+ if (ret) {
+ ret = -errno;
+ dout(0) << "destroy_checkpoint: ioctl SNAP_DESTROY got " << cpp_strerror(ret) << dendl;
+ return ret;
+ }
+ return 0;
+}
+
+int BtrfsFileStoreBackend::syncfs()
+{
+ dout(15) << "syncfs" << dendl;
+ // do a full btrfs commit
+ int ret = ::ioctl(get_op_fd(), BTRFS_IOC_SYNC);
+ if (ret < 0) {
+ ret = -errno;
+ dout(0) << "syncfs: btrfs IOC_SYNC got " << cpp_strerror(ret) << dendl;
+ }
+ return ret;
+}
+
+int BtrfsFileStoreBackend::clone_range(int from, int to, uint64_t srcoff, uint64_t len, uint64_t dstoff)
+{
+ dout(20) << "clone_range: " << srcoff << "~" << len << " to " << dstoff << dendl;
+ size_t blk_size = get_blksize();
+ if (!has_clone_range ||
+ srcoff % blk_size != dstoff % blk_size) {
+ dout(20) << "clone_range: using copy" << dendl;
+ return _copy_range(from, to, srcoff, len, dstoff);
+ }
+
+ int err = 0;
+ int r = 0;
+
+ uint64_t srcoffclone = ALIGN_UP(srcoff, blk_size);
+ uint64_t dstoffclone = ALIGN_UP(dstoff, blk_size);
+ if (srcoffclone >= srcoff + len) {
+ dout(20) << "clone_range: using copy, extent too short to align srcoff" << dendl;
+ return _copy_range(from, to, srcoff, len, dstoff);
+ }
+
+ uint64_t lenclone = len - (srcoffclone - srcoff);
+ if (!ALIGNED(lenclone, blk_size)) {
+ struct stat from_stat, to_stat;
+ err = ::fstat(from, &from_stat);
+ if (err) return -errno;
+ err = ::fstat(to , &to_stat);
+ if (err) return -errno;
+
+ if (srcoff + len != (uint64_t)from_stat.st_size ||
+ dstoff + len < (uint64_t)to_stat.st_size) {
+ // Not to the end of the file, need to align length as well
+ lenclone = ALIGN_DOWN(lenclone, blk_size);
+ }
+ }
+ if (lenclone == 0) {
+ // too short
+ return _copy_range(from, to, srcoff, len, dstoff);
+ }
+
+ dout(20) << "clone_range: cloning " << srcoffclone << "~" << lenclone
+ << " to " << dstoffclone << " = " << r << dendl;
+ btrfs_ioctl_clone_range_args a;
+ a.src_fd = from;
+ a.src_offset = srcoffclone;
+ a.src_length = lenclone;
+ a.dest_offset = dstoffclone;
+ err = ::ioctl(to, BTRFS_IOC_CLONE_RANGE, &a);
+ if (err >= 0) {
+ r += err;
+ } else if (errno == EINVAL) {
+ // Still failed, might be compressed
+ dout(20) << "clone_range: failed CLONE_RANGE call with -EINVAL, using copy" << dendl;
+ return _copy_range(from, to, srcoff, len, dstoff);
+ } else {
+ return -errno;
+ }
+
+ // Take care any trimmed from front
+ if (srcoffclone != srcoff) {
+ err = _copy_range(from, to, srcoff, srcoffclone - srcoff, dstoff);
+ if (err >= 0) {
+ r += err;
+ } else {
+ return err;
+ }
+ }
+
+ // Copy end
+ if (srcoffclone + lenclone != srcoff + len) {
+ err = _copy_range(from, to,
+ srcoffclone + lenclone,
+ (srcoff + len) - (srcoffclone + lenclone),
+ dstoffclone + lenclone);
+ if (err >= 0) {
+ r += err;
+ } else {
+ return err;
+ }
+ }
+ dout(20) << "clone_range: finished " << srcoff << "~" << len
+ << " to " << dstoff << " = " << r << dendl;
+ return r;
+}
+#endif
Code Review / stor4nfv.git / blobdiff