ext2fs_open_inode_scan: Handle an non-zero bg_itable_used in block group 0

Previously, the portion of the inode table for block group 0 was
always completely zero'ed out, so the ext2fs_open_inode_scan() didn't
handle a non-zero bg_itable_used value for the first block group.  Fix
this.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

diff --git a/lib/ext2fs/inode.c b/lib/ext2fs/inode.c
index d9150fb..8908423 100644 (file)
--- a/lib/ext2fs/inode.c
+++ b/lib/ext2fs/inode.c
@@ -146,6 +146,15 @@ errcode_t ext2fs_open_inode_scan(ext2_filsys fs, int buffer_blocks,
                group_desc[scan->current_group].bg_inode_table;
        scan->inodes_left = EXT2_INODES_PER_GROUP(scan->fs->super);
        scan->blocks_left = scan->fs->inode_blocks_per_group;
+       if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+                                      EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
+               scan->inodes_left -=
+                       fs->group_desc[scan->current_group].bg_itable_unused;
+               scan->blocks_left =
+                       (scan->inodes_left +
+                        (fs->blocksize / scan->inode_size - 1)) *
+                       scan->inode_size / fs->blocksize;
+       }
        retval = ext2fs_get_array(scan->inode_buffer_blocks,
                                          fs->blocksize,
                                &scan->inode_buffer);