1 files changed, 149 insertions, 0 deletions
diff --git a/src/os/filestore/XfsFileStoreBackend.cc b/src/os/filestore/XfsFileStoreBackend.cc
new file mode 100644
index 00000000..1081d146
--- /dev/null
+++ b/src/os/filestore/XfsFileStoreBackend.cc
@@ -0,0 +1,149 @@
+// -*- 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) 2014 Inktank, Inc
+ *
+ * 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 "XfsFileStoreBackend.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <sys/utsname.h>
+
+#include <xfs/xfs.h>
+
+#include "common/errno.h"
+#include "common/linux_version.h"
+#include "include/ceph_assert.h"
+#include "include/compat.h"
+
+#define dout_context cct()
+#define dout_subsys ceph_subsys_filestore
+#undef dout_prefix
+#define dout_prefix *_dout << "xfsfilestorebackend(" << get_basedir_path() << ") "
+
+XfsFileStoreBackend::XfsFileStoreBackend(FileStore *fs):
+  GenericFileStoreBackend(fs), m_has_extsize(false) { }
+
+/*
+ * Set extsize attr on a file to val.  Should be a free-standing
+ * function, but dout_prefix expanding to a call to get_basedir_path()
+ * protected member function won't let it.
+ */
+int XfsFileStoreBackend::set_extsize(int fd, unsigned int val)
+{
+  struct fsxattr fsx;
+  struct stat sb;
+  int ret;
+
+  if (fstat(fd, &sb) < 0) {
+    ret = -errno;
+    dout(0) << "set_extsize: fstat: " << cpp_strerror(ret) << dendl;
+    return ret;
+  }
+  if (!S_ISREG(sb.st_mode)) {
+    dout(0) << "set_extsize: invalid target file type" << dendl;
+    return -EINVAL;
+  }
+
+  if (ioctl(fd, XFS_IOC_FSGETXATTR, &fsx) < 0) {
+    ret = -errno;
+    dout(0) << "set_extsize: FSGETXATTR: " << cpp_strerror(ret) << dendl;
+    return ret;
+  }
+
+  // already set?
+  if ((fsx.fsx_xflags & XFS_XFLAG_EXTSIZE) && fsx.fsx_extsize == val)
+    return 0;
+
+  // xfs won't change extent size if any extents are allocated
+  if (fsx.fsx_nextents != 0)
+    return 0;
+
+  fsx.fsx_xflags |= XFS_XFLAG_EXTSIZE;
+  fsx.fsx_extsize = val;
+
+  if (ioctl(fd, XFS_IOC_FSSETXATTR, &fsx) < 0) {
+    ret = -errno;
+    dout(0) << "set_extsize: FSSETXATTR: " << cpp_strerror(ret) << dendl;
+    return ret;
+  }
+
+  return 0;
+}
+
+int XfsFileStoreBackend::detect_features()
+{
+  int ret;
+
+  ret = GenericFileStoreBackend::detect_features();
+  if (ret < 0)
+    return ret;
+
+  // extsize?
+  int fd = ::openat(get_basedir_fd(), "extsize_test", O_CREAT|O_WRONLY, 0600);
+  if (fd < 0) {
+    ret = -errno;
+    dout(0) << "detect_feature: failed to create test file for extsize attr: "
+            << cpp_strerror(ret) << dendl;
+    goto out;
+  }
+  if (::unlinkat(get_basedir_fd(), "extsize_test", 0) < 0) {
+    ret = -errno;
+    dout(0) << "detect_feature: failed to unlink test file for extsize attr: "
+            << cpp_strerror(ret) << dendl;
+    goto out_close;
+  }
+
+  if (cct()->_conf->filestore_xfs_extsize) {
+    ret = set_extsize(fd, 1U << 15); // a few pages
+    if (ret) {
+      ret = 0;
+      dout(0) << "detect_feature: failed to set test file extsize, assuming extsize is NOT supported" << dendl;
+      goto out_close;
+    }
+
+    // make sure we have 3.5 or newer, which includes this fix
+    //   aff3a9edb7080f69f07fe76a8bd089b3dfa4cb5d
+    // for this set_extsize bug
+    //   http://oss.sgi.com/bugzilla/show_bug.cgi?id=874
+    int ver = get_linux_version();
+    if (ver == 0) {
+      dout(0) << __func__ << ": couldn't verify extsize not buggy, disabling extsize" << dendl;
+      m_has_extsize = false;
+    } else if (ver < KERNEL_VERSION(3, 5, 0)) {
+      dout(0) << __func__ << ": disabling extsize, your kernel < 3.5 and has buggy extsize ioctl" << dendl;
+      m_has_extsize = false;
+    } else {
+      dout(0) << __func__ << ": extsize is supported and your kernel >= 3.5" << dendl;
+      m_has_extsize = true;
+    }
+  } else {
+    dout(0) << "detect_feature: extsize is disabled by conf" << dendl;
+  }
+
+out_close:
+  TEMP_FAILURE_RETRY(::close(fd));
+out:
+  return ret;
+}
+
+int XfsFileStoreBackend::set_alloc_hint(int fd, uint64_t hint)
+{
+  if (!m_has_extsize)
+    return -EOPNOTSUPP;
+
+  ceph_assert(hint < UINT_MAX);
+  return set_extsize(fd, hint);
+}