X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;f=src%2Fceph%2Fsrc%2Fos%2Ffilestore%2FBtrfsFileStoreBackend.cc;fp=src%2Fceph%2Fsrc%2Fos%2Ffilestore%2FBtrfsFileStoreBackend.cc;h=8718432ec671647206254d37744e69b9d9509723;hb=812ff6ca9fcd3e629e49d4328905f33eee8ca3f5;hp=0000000000000000000000000000000000000000;hpb=15280273faafb77777eab341909a3f495cf248d9;p=stor4nfv.git

diff --git a/src/ceph/src/os/filestore/BtrfsFileStoreBackend.cc b/src/ceph/src/os/filestore/BtrfsFileStoreBackend.cc
new file mode 100644
index 0000000..8718432
--- /dev/null
+++ b/src/ceph/src/os/filestore/BtrfsFileStoreBackend.cc
@@ -0,0 +1,575 @@
+// -*- 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(), &currentfs);
+    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