btrfs-progs: limit the max value of leafsize and nodesize

Using mkfs.btrfs like:

        mkfs.btrfs -l 131072 /dev/sda

will return no error, but after mount it, the dmesg will report:

	BTRFS: couldn't mount because metadata blocksize (131072) was too large

The leafsize and nodesize are equal at present, so we just use one function
"check_leaf_or_node_size" to limit leaf and node size below BTRFS_MAX_METADATA_BLOCKSIZE.

Signed-off-by: Robin Dong <sanbai@taobao.com>
Reviewed-by: David Sterba <dave@jikos.cz>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/ctree.h b/ctree.h
index 4bb66fff..293b24fe 100644
--- a/ctree.h
+++ b/ctree.h
@@ -111,6 +111,12 @@ struct btrfs_trans_handle;
 #define BTRFS_DEV_ITEMS_OBJECTID 1ULL
 
 /*
+ * the max metadata block size.  This limit is somewhat artificial,
+ * but the memmove costs go through the roof for larger blocks.
+ */
+#define BTRFS_MAX_METADATA_BLOCKSIZE 65536
+
+/*
  * we can actually store much bigger names, but lets not confuse the rest
  * of linux
  */