Implement .commit_metadata hook for NFS export

In order to implement synchronous NFS metadata semantics ZFS
needs to provide the .commit_metadata hook.  All it takes there
is to make sure changes are committed to ZIL.  Fortunately
zfs_fsync() does just that, so simply calling it from
zpl_commit_metadata() does the trick.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #969
This commit is contained in:
Cyril Plisko 2012-09-16 09:03:04 +03:00 committed by Brian Behlendorf
parent 23a61ccc1b
commit 393b44c711
3 changed files with 45 additions and 1 deletions

View File

@ -0,0 +1,23 @@
dnl #
dnl # 2.6.33 API change
dnl # Added eops->commit_metadata() callback to allow the underlying
dnl # filesystem to determine the most efficient way to commit the inode.
dnl # Prior to this the nfs server would issue an explicit fsync().
dnl #
AC_DEFUN([ZFS_AC_KERNEL_COMMIT_METADATA], [
AC_MSG_CHECKING([whether eops->commit_metadata() exists])
ZFS_LINUX_TRY_COMPILE([
#include <linux/exportfs.h>
int commit_metadata(struct inode *inode) { return 0; }
static struct export_operations eops __attribute__ ((unused))={
.commit_metadata = commit_metadata,
};
],[
],[
AC_MSG_RESULT(yes)
AC_DEFINE(HAVE_COMMIT_METADATA, 1,
[eops->commit_metadata() exists])
],[
AC_MSG_RESULT(no)
])
])

View File

@ -53,6 +53,7 @@ AC_DEFUN([ZFS_AC_CONFIG_KERNEL], [
ZFS_AC_KERNEL_CREATE_UMODE_T
ZFS_AC_KERNEL_AUTOMOUNT
ZFS_AC_KERNEL_ENCODE_FH_WITH_INODE
ZFS_AC_KERNEL_COMMIT_METADATA
ZFS_AC_KERNEL_CLEAR_INODE
ZFS_AC_KERNEL_INSERT_INODE_LOCKED
ZFS_AC_KERNEL_D_MAKE_ROOT

View File

@ -20,6 +20,7 @@
*/
/*
* Copyright (c) 2011 Gunnar Beutner
* Copyright (c) 2012 Cyril Plisko. All rights reserved.
*/
@ -121,8 +122,27 @@ zpl_get_parent(struct dentry *child)
return zpl_dentry_obtain_alias(ip);
}
#ifdef HAVE_COMMIT_METADATA
static int
zpl_commit_metadata(struct inode *inode)
{
cred_t *cr = CRED();
int error;
crhold(cr);
error = -zfs_fsync(inode, 0, cr);
crfree(cr);
ASSERT3S(error, <=, 0);
return error;
}
#endif /* HAVE_COMMIT_METADATA */
const struct export_operations zpl_export_operations = {
.encode_fh = zpl_encode_fh,
.fh_to_dentry = zpl_fh_to_dentry,
.get_parent = zpl_get_parent
.get_parent = zpl_get_parent,
#ifdef HAVE_COMMIT_METADATA
.commit_metadata= zpl_commit_metadata,
#endif /* HAVE_COMMIT_METADATA */
};