1 files changed, 88 insertions, 0 deletions

diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c
index 67dec11e34c7..4e321bb81991 100644
--- a/fs/xfs/xfs_trans.c
+++ b/fs/xfs/xfs_trans.c
@@ -135,6 +135,62 @@ xfs_trans_dup(
 }
 
 /*
+ * Try to reserve more blocks for a transaction.
+ *
+ * This is for callers that need to attach resources to a transaction, scan
+ * those resources to determine the space reservation requirements, and then
+ * modify the attached resources.  In other words, online repair.  This can
+ * fail due to ENOSPC, so the caller must be able to cancel the transaction
+ * without shutting down the fs.
+ */
+int
+xfs_trans_reserve_more(
+	struct xfs_trans	*tp,
+	unsigned int		blocks,
+	unsigned int		rtextents)
+{
+	struct xfs_mount	*mp = tp->t_mountp;
+	bool			rsvd = (tp->t_flags & XFS_TRANS_RESERVE) != 0;
+	int			error = 0;
+
+	ASSERT(!(tp->t_flags & XFS_TRANS_DIRTY));
+
+	/*
+	 * Attempt to reserve the needed disk blocks by decrementing
+	 * the number needed from the number available.  This will
+	 * fail if the count would go below zero.
+	 */
+	if (blocks > 0) {
+		error = xfs_mod_fdblocks(mp, -((int64_t)blocks), rsvd);
+		if (error)
+			return -ENOSPC;
+		tp->t_blk_res += blocks;
+	}
+
+	/*
+	 * Attempt to reserve the needed realtime extents by decrementing
+	 * the number needed from the number available.  This will
+	 * fail if the count would go below zero.
+	 */
+	if (rtextents > 0) {
+		error = xfs_mod_frextents(mp, -((int64_t)rtextents));
+		if (error) {
+			error = -ENOSPC;
+			goto out_blocks;
+		}
+		tp->t_rtx_res += rtextents;
+	}
+
+	return 0;
+out_blocks:
+	if (blocks > 0) {
+		xfs_mod_fdblocks(mp, (int64_t)blocks, rsvd);
+		tp->t_blk_res -= blocks;
+	}
+	return error;
+}
+
+/*
  * This is called to reserve free disk blocks and log space for the
  * given transaction.  This must be done before allocating any resources
  * within the transaction.
@@ -1080,6 +1136,38 @@ out_cancel:
 	return error;
 }
 
+
+/* Try to reserve more blocks and file quota for a transaction. */
+int
+xfs_trans_reserve_more_inode(
+	struct xfs_trans	*tp,
+	struct xfs_inode	*ip,
+	unsigned int		dblocks,
+	unsigned int		rblocks)
+{
+	struct xfs_mount	*mp = ip->i_mount;
+	unsigned int		rtx = rblocks / mp->m_sb.sb_rextsize;
+	bool			rsvd = (tp->t_flags & XFS_TRANS_RESERVE) != 0;
+	int			error;
+
+	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
+
+	error = xfs_trans_reserve_more(tp, dblocks, rtx);
+	if (error)
+		return error;
+
+	error = xfs_trans_reserve_quota_nblks(tp, ip, dblocks, rblocks, rsvd);
+	if (!error)
+		return 0;
+
+	/* Quota failed, give back the new reservation. */
+	xfs_mod_fdblocks(mp, dblocks, rsvd);
+	tp->t_blk_res -= dblocks;
+	xfs_mod_frextents(mp, rtx);
+	tp->t_rtx_res -= rtx;
+	return error;
+}
+
 /*
  * Allocate an transaction in preparation for inode creation by reserving quota
  * against the given dquots.  Callers are not required to hold any inode locks.