}
/*
- * xfs_fsync
- *
- * This is called to sync the inode and its data out to disk. We need to hold
- * the I/O lock while flushing the data, and the inode lock while flushing the
- * inode. The inode lock CANNOT be held while flushing the data, so acquire
- * after we're done with that.
- */
-int
-xfs_fsync(
- xfs_inode_t *ip)
-{
- xfs_trans_t *tp;
- int error = 0;
- int log_flushed = 0;
-
- xfs_itrace_entry(ip);
-
- if (XFS_FORCED_SHUTDOWN(ip->i_mount))
- return XFS_ERROR(EIO);
-
- /*
- * We always need to make sure that the required inode state is safe on
- * disk. The inode might be clean but we still might need to force the
- * log because of committed transactions that haven't hit the disk yet.
- * Likewise, there could be unflushed non-transactional changes to the
- * inode core that have to go to disk and this requires us to issue
- * a synchronous transaction to capture these changes correctly.
- *
- * This code relies on the assumption that if the update_* fields
- * of the inode are clear and the inode is unpinned then it is clean
- * and no action is required.
- */
- xfs_ilock(ip, XFS_ILOCK_SHARED);
-
- if (!ip->i_update_core) {
- /*
- * Timestamps/size haven't changed since last inode flush or
- * inode transaction commit. That means either nothing got
- * written or a transaction committed which caught the updates.
- * If the latter happened and the transaction hasn't hit the
- * disk yet, the inode will be still be pinned. If it is,
- * force the log.
- */
- xfs_iunlock(ip, XFS_ILOCK_SHARED);
- if (xfs_ipincount(ip)) {
- error = _xfs_log_force(ip->i_mount, XFS_LOG_SYNC,
- &log_flushed);
- }
- } else {
- /*
- * Kick off a transaction to log the inode core to get the
- * updates. The sync transaction will also force the log.
- */
- xfs_iunlock(ip, XFS_ILOCK_SHARED);
- tp = xfs_trans_alloc(ip->i_mount, XFS_TRANS_FSYNC_TS);
- error = xfs_trans_reserve(tp, 0,
- XFS_FSYNC_TS_LOG_RES(ip->i_mount), 0, 0, 0);
- if (error) {
- xfs_trans_cancel(tp, 0);
- return error;
- }
- xfs_ilock(ip, XFS_ILOCK_EXCL);
-
- /*
- * Note - it's possible that we might have pushed ourselves out
- * of the way during trans_reserve which would flush the inode.
- * But there's no guarantee that the inode buffer has actually
- * gone out yet (it's delwri). Plus the buffer could be pinned
- * anyway if it's part of an inode in another recent
- * transaction. So we play it safe and fire off the
- * transaction anyway.
- */
- xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
- xfs_trans_ihold(tp, ip);
- xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
- xfs_trans_set_sync(tp);
- error = _xfs_trans_commit(tp, 0, &log_flushed);
-
- xfs_iunlock(ip, XFS_ILOCK_EXCL);
- }
-
- if (ip->i_mount->m_flags & XFS_MOUNT_BARRIER) {
- /*
- * If the log write didn't issue an ordered tag we need
- * to flush the disk cache for the data device now.
- */
- if (!log_flushed)
- xfs_blkdev_issue_flush(ip->i_mount->m_ddev_targp);
-
- /*
- * If this inode is on the RT dev we need to flush that
- * cache as well.
- */
- if (XFS_IS_REALTIME_INODE(ip))
- xfs_blkdev_issue_flush(ip->i_mount->m_rtdev_targp);
- }
-
- return error;
-}
-
-/*
* Flags for xfs_free_eofblocks
*/
#define XFS_FREE_EOF_TRYLOCK (1<<0)
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