xfs: support creating per-RTG files in growfs

To support adding new RT groups in growfs, we need to be able to create
the per-RT group files.  Add a new xfs_rtginode_create helper to create
a given per-RTG file.  Most of the code for that is shared, but the
details of the actual file are abstracted out using a new create method
in struct xfs_rtginode_ops.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>

1 files changed, 30 insertions, 0 deletions

diff --git a/fs/xfs/xfs_rtalloc.c b/fs/xfs/xfs_rtalloc.c
index 3b3ce971a197..5c1df67b63d6 100644
--- a/fs/xfs/xfs_rtalloc.c
+++ b/fs/xfs/xfs_rtalloc.c
@@ -711,6 +711,29 @@ out_iolock:
 	return error;
 }
 
+/* Ensure that the rtgroup metadata inode is loaded, creating it if neeeded. */
+static int
+xfs_rtginode_ensure(
+	struct xfs_rtgroup	*rtg,
+	enum xfs_rtg_inodes	type)
+{
+	struct xfs_trans	*tp;
+	int			error;
+
+	if (rtg->rtg_inodes[type])
+		return 0;
+
+	error = xfs_trans_alloc_empty(rtg_mount(rtg), &tp);
+	if (error)
+		return error;
+	error = xfs_rtginode_load(rtg, type, tp);
+	xfs_trans_cancel(tp);
+
+	if (error != -ENOENT)
+		return 0;
+	return xfs_rtginode_create(rtg, type, true);
+}
+
 static int
 xfs_growfs_rt_bmblock(
 	struct xfs_rtgroup	*rtg,
@@ -927,12 +950,19 @@ xfs_growfs_rtg(
 	xfs_extlen_t		bmblocks;
 	xfs_fileoff_t		bmbno;
 	struct xfs_rtgroup	*rtg;
+	unsigned int		i;
 	int			error;
 
 	rtg = xfs_rtgroup_grab(mp, 0);
 	if (!rtg)
 		return -EINVAL;
 
+	for (i = 0; i < XFS_RTGI_MAX; i++) {
+		error = xfs_rtginode_ensure(rtg, i);
+		if (error)
+			goto out_rele;
+	}
+
 	error = xfs_growfs_rt_alloc_blocks(rtg, nrblocks, rextsize, &bmblocks);
 	if (error)
 		goto out_rele;