[PATCH] db: increase metadump's default overly long extent discard threshold

["Darrick J. Wong" <darrick.wong@oracle.com>]

Back in 88b8e1d6d7 ("Make xfs_metadump more robust against bad data"),
metadump grew the ability to ignore a directory extent if it was longer
than 20 blocks.  Presumably this was to protect metadump from dumping
absurdly long extents resulting from bmbt corruption, but it's certainly
possible to create a directory with an extent longer than 20 blocks.
Hilariously, the discards happen with no warning unless the caller
explicitly set -w.

This was raised to 1000 blocks in 7431d134fe8 ("Increase default maximum
extent size for xfs_metadump when copying..."), but it's still possible
to create a directory with an extent longer than 1000 blocks.

Increase the threshold to MAXEXTLEN blocks because it's totally valid
for the filesystem to create extents up to that length.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 db/metadump.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/db/metadump.c b/db/metadump.c
index c179480..c8eb8f0 100644
--- a/db/metadump.c
+++ b/db/metadump.c
@@ -32,7 +32,7 @@
 #include "field.h"
 #include "dir2.h"
 
-#define DEFAULT_MAX_EXT_SIZE	1000
+#define DEFAULT_MAX_EXT_SIZE	MAXEXTLEN
 
 /*
  * It's possible that multiple files in a directory (or attributes