xfs_copy: band-aids for CRC filesystems

xfs_copy needs a fair bit of work for CRCs because it rewrites
UUIDs by default, but this change will get it working properly
with the "-d" (duplicate) option which keeps the same UUID.

Accept the the CRC magic valid, change the ASSERT() to an error
message and exit more gracefully, and don't
even get started if we don't have the '-d' option.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>

diff --git a/copy/xfs_copy.c b/copy/xfs_copy.c
index 9986fbf60a04915a5a00281038d17f435a5dc710..9f2f99dcb72907288c5d46da63860991bac39d09 100644 (file)
--- a/copy/xfs_copy.c
+++ b/copy/xfs_copy.c
@@ -684,6 +684,16 @@ main(int argc, char **argv)
        sb = &mbuf.m_sb;
        libxfs_sb_from_disk(sb, XFS_BUF_TO_SBP(sbp));
 
+       /*
+        * For now, V5 superblock filesystems are not supported without -d;
+        * we do not have the infrastructure yet to fix CRCs when a new UUID
+        * is generated.
+        */
+       if (xfs_sb_version_hascrc(sb) && !duplicate) {
+               do_log(_("%s: Cannot yet copy V5 fs without '-d'\n"), progname);
+               exit(1);
+       }
+
        mp = libxfs_mount(&mbuf, sb, xargs.ddev, xargs.logdev, xargs.rtdev, 0);
        if (mp == NULL) {
                do_log(_("%s: %s filesystem failed to initialize\n"
@@ -957,7 +967,13 @@ main(int argc, char **argv)
                                 ((char *)btree_buf.data +
                                  pos - btree_buf.position);
 
-                       ASSERT(be32_to_cpu(block->bb_magic) == XFS_ABTB_MAGIC);
+                       if (be32_to_cpu(block->bb_magic) !=
+                           (xfs_sb_version_hascrc(&mp->m_sb) ?
+                            XFS_ABTB_CRC_MAGIC : XFS_ABTB_MAGIC)) {
+                               do_log(_("Bad btree magic 0x%x\n"),
+                                       be32_to_cpu(block->bb_magic));
+                               exit(1);
+                       }
 
                        if (be16_to_cpu(block->bb_level) == 0)
                                break;