resize2fs: don't free in-use clusters when moving blocks

When we're moving blocks around the filesystem, ensure that freeing
the old blocks only frees the clusters if they're not in use by other
metadata.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

diff --git a/resize/resize2fs.c b/resize/resize2fs.c
index caff422..6b9ca09 100644 (file)
--- a/resize/resize2fs.c
+++ b/resize/resize2fs.c
@@ -909,12 +909,12 @@ static errcode_t blocks_to_move(ext2_resize_t rfs)
        int             j, has_super;
        dgrp_t          i, max_groups, g;
        blk64_t         blk, group_blk;
-       blk64_t         old_blocks, new_blocks;
+       blk64_t         old_blocks, new_blocks, group_end, cluster_freed;
        blk64_t         new_size;
        unsigned int    meta_bg, meta_bg_size;
        errcode_t       retval;
        ext2_filsys     fs, old_fs;
-       ext2fs_block_bitmap     meta_bmap;
+       ext2fs_block_bitmap     meta_bmap, new_meta_bmap = NULL;
        int             flex_bg;
 
        fs = rfs->new_fs;
@@ -1026,15 +1026,42 @@ static errcode_t blocks_to_move(ext2_resize_t rfs)
         * blocks as free.
         */
        if (old_blocks > new_blocks) {
+               if (EXT2FS_CLUSTER_RATIO(fs) > 1) {
+                       retval = ext2fs_allocate_block_bitmap(fs,
+                                                       _("new meta blocks"),
+                                                       &new_meta_bmap);
+                       if (retval)
+                               goto errout;
+
+                       retval = mark_table_blocks(fs, new_meta_bmap);
+                       if (retval)
+                               goto errout;
+               }
+
                for (i = 0; i < max_groups; i++) {
                        if (!ext2fs_bg_has_super(fs, i)) {
                                group_blk += fs->super->s_blocks_per_group;
                                continue;
                        }
-                       for (blk = group_blk+1+new_blocks;
-                            blk < group_blk+1+old_blocks; blk++) {
-                               ext2fs_block_alloc_stats2(fs, blk, -1);
+                       group_end = group_blk + 1 + old_blocks;
+                       for (blk = group_blk + 1 + new_blocks;
+                            blk < group_end;) {
+                               if (new_meta_bmap == NULL ||
+                                   !ext2fs_test_block_bitmap2(new_meta_bmap,
+                                                              blk)) {
+                                       cluster_freed =
+                                               EXT2FS_CLUSTER_RATIO(fs) -
+                                               (blk &
+                                                EXT2FS_CLUSTER_MASK(fs));
+                                       if (cluster_freed > group_end - blk)
+                                               cluster_freed = group_end - blk;
+                                       ext2fs_block_alloc_stats2(fs, blk, -1);
+                                       blk += EXT2FS_CLUSTER_RATIO(fs);
+                                       rfs->needed_blocks -= cluster_freed;
+                                       continue;
+                               }
                                rfs->needed_blocks--;
+                               blk++;
                        }
                        group_blk += fs->super->s_blocks_per_group;
                }
@@ -1180,6 +1207,8 @@ static errcode_t blocks_to_move(ext2_resize_t rfs)
        retval = 0;
 
 errout:
+       if (new_meta_bmap)
+               ext2fs_free_block_bitmap(new_meta_bmap);
        if (meta_bmap)
                ext2fs_free_block_bitmap(meta_bmap);
 
@@ -1779,9 +1808,10 @@ static errcode_t move_itables(ext2_resize_t rfs)
        dgrp_t          i, max_groups;
        ext2_filsys     fs = rfs->new_fs;
        char            *cp;
-       blk64_t         old_blk, new_blk, blk;
+       blk64_t         old_blk, new_blk, blk, cluster_freed;
        errcode_t       retval;
        int             j, to_move, moved;
+       ext2fs_block_bitmap     new_bmap = NULL;
 
        max_groups = fs->group_desc_count;
        if (max_groups > rfs->old_fs->group_desc_count)
@@ -1794,6 +1824,17 @@ static errcode_t move_itables(ext2_resize_t rfs)
                        return retval;
        }
 
+       if (EXT2FS_CLUSTER_RATIO(fs) > 1) {
+               retval = ext2fs_allocate_block_bitmap(fs, _("new meta blocks"),
+                                                     &new_bmap);
+               if (retval)
+                       return retval;
+
+               retval = mark_table_blocks(fs, new_bmap);
+               if (retval)
+                       goto errout;
+       }
+
        /*
         * Figure out how many inode tables we need to move
         */
@@ -1871,8 +1912,19 @@ static errcode_t move_itables(ext2_resize_t rfs)
                }
 
                for (blk = ext2fs_inode_table_loc(rfs->old_fs, i), j=0;
-                    j < fs->inode_blocks_per_group ; j++, blk++)
-                       ext2fs_block_alloc_stats2(fs, blk, -1);
+                    j < fs->inode_blocks_per_group;) {
+                       if (new_bmap == NULL ||
+                           !ext2fs_test_block_bitmap2(new_bmap, blk)) {
+                               ext2fs_block_alloc_stats2(fs, blk, -1);
+                               cluster_freed = EXT2FS_CLUSTER_RATIO(fs) -
+                                               (blk & EXT2FS_CLUSTER_MASK(fs));
+                               blk += cluster_freed;
+                               j += cluster_freed;
+                               continue;
+                       }
+                       blk++;
+                       j++;
+               }
 
                ext2fs_inode_table_loc_set(rfs->old_fs, i, new_blk);
                ext2fs_group_desc_csum_set(rfs->old_fs, i);
@@ -1892,9 +1944,11 @@ static errcode_t move_itables(ext2_resize_t rfs)
        if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
                printf("Inode table move finished.\n");
 #endif
-       return 0;
+       retval = 0;
 
 errout:
+       if (new_bmap)
+               ext2fs_free_block_bitmap(new_bmap);
        return retval;
 }