Fix resize2fs so that it properly handles filesystems with the resize_inode

feature enabled.

diff --git a/resize/ChangeLog b/resize/ChangeLog
index 10aacd2..838abaf 100644 (file)
--- a/resize/ChangeLog
+++ b/resize/ChangeLog
@@ -1,3 +1,10 @@
+2004-12-16  Theodore Ts'o  <tytso@mit.edu>
+
+       * resize2fs.c (resize_fs): Call ext2fs_create_resize_inode to
+               fill in the necessary fields in the resize inode.
+               (adjust_superblock): Reserve blocks that are needed for
+               on-line resizing if that feature is enabled.
+
 2004-12-14  Theodore Ts'o  <tytso@mit.edu>
 
        * Makefile.in: Move strip command to install-strip target.

diff --git a/resize/resize2fs.c b/resize/resize2fs.c
index 3befbaa..5ad77d6 100644 (file)
--- a/resize/resize2fs.c
+++ b/resize/resize2fs.c
@@ -46,6 +46,7 @@ static errcode_t block_mover(ext2_resize_t rfs);
 static errcode_t inode_scan_and_fix(ext2_resize_t rfs);
 static errcode_t inode_ref_fix(ext2_resize_t rfs);
 static errcode_t move_itables(ext2_resize_t rfs);
+static errcode_t fix_resize_inode(ext2_filsys fs);
 static errcode_t ext2fs_calculate_summary_stats(ext2_filsys fs);
 
 /*
@@ -133,6 +134,10 @@ errcode_t resize_fs(ext2_filsys fs, blk_t *new_size, int flags,
        if (retval)
                goto errout;
 
+       retval = fix_resize_inode(rfs->new_fs);
+       if (retval)
+               goto errout;
+
        retval = ext2fs_close(rfs->new_fs);
        if (retval)
                goto errout;
@@ -205,12 +210,13 @@ retry:
         * includes the superblock backup, the group descriptor
         * backups, the inode bitmap, the block bitmap, and the inode
         * table.
-        *
-        * XXX Not all block groups need the descriptor blocks, but
-        * being clever is tricky...
         */
-       overhead = 3 + fs->desc_blocks + fs->inode_blocks_per_group;
-       
+       overhead = (int) (2 + fs->inode_blocks_per_group);
+
+       if (ext2fs_bg_has_super(fs, fs->group_desc_count - 1))
+               overhead += 1 + fs->desc_blocks + 
+                       fs->super->s_reserved_gdt_blocks;
+
        /*
         * See if the last group is big enough to support the
         * necessary data structures.  If not, we need to get rid of
@@ -288,6 +294,29 @@ retry:
        }
 
        /*
+        * If the resize_inode feature is set, and we are changing the
+        * number of descriptor blocks, then adjust
+        * s_reserved_gdt_blocks if possible to avoid needing to move
+        * the inode table either now or in the future.
+        */
+       if ((fs->super->s_feature_compat & 
+            EXT2_FEATURE_COMPAT_RESIZE_INODE) &&
+           (rfs->old_fs->desc_blocks != fs->desc_blocks)) {
+               int new;
+
+               new = ((int) fs->super->s_reserved_gdt_blocks) + 
+                       (rfs->old_fs->desc_blocks - fs->desc_blocks);
+               if (new < 0)
+                       new = 0;
+               if (new > fs->blocksize/4)
+                       new = fs->blocksize/4;
+               fs->super->s_reserved_gdt_blocks = new;
+               if (new == 0)
+                       fs->super->s_feature_compat &= 
+                               ~EXT2_FEATURE_COMPAT_RESIZE_INODE;
+       }
+
+       /*
         * If we are shrinking the number block groups, we're done and
         * can exit now.
         */
@@ -346,7 +375,8 @@ retry:
        if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
                old_desc_blocks = fs->super->s_first_meta_bg;
        else
-               old_desc_blocks = fs->desc_blocks;
+               old_desc_blocks = fs->desc_blocks + 
+                       fs->super->s_reserved_gdt_blocks;
        for (i = rfs->old_fs->group_desc_count;
             i < fs->group_desc_count; i++) {
                memset(&fs->group_desc[i], 0,
@@ -466,7 +496,8 @@ static errcode_t mark_table_blocks(ext2_filsys fs,
        if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
                old_desc_blocks = fs->super->s_first_meta_bg;
        else
-               old_desc_blocks = fs->desc_blocks;
+               old_desc_blocks = fs->desc_blocks + 
+                       fs->super->s_reserved_gdt_blocks;
        for (i = 0; i < fs->group_desc_count; i++) {
                has_super = ext2fs_bg_has_super(fs, i);
                if (has_super)
@@ -613,8 +644,8 @@ static errcode_t blocks_to_move(ext2_resize_t rfs)
                old_blocks = old_fs->super->s_first_meta_bg;
                new_blocks = fs->super->s_first_meta_bg;
        } else {
-               old_blocks = old_fs->desc_blocks;
-               new_blocks = fs->desc_blocks;
+               old_blocks = old_fs->desc_blocks + old_fs->super->s_reserved_gdt_blocks;
+               new_blocks = fs->desc_blocks + fs->super->s_reserved_gdt_blocks;
        }
        
        if (old_blocks == new_blocks) {
@@ -1100,7 +1131,7 @@ static errcode_t inode_scan_and_fix(ext2_resize_t rfs)
                if (!ino)
                        break;
 
-               if (inode.i_links_count == 0)
+               if (inode.i_links_count == 0 && ino != EXT2_RESIZE_INO)
                        continue; /* inode not in use */
 
                pb.is_dir = LINUX_S_ISDIR(inode.i_mode);
@@ -1428,6 +1459,57 @@ errout:
 }
 
 /*
+ * Fix the resize inode 
+ */
+static errcode_t fix_resize_inode(ext2_filsys fs)
+{
+       struct ext2_inode       inode;
+       errcode_t               retval;
+       char *                  block_buf;
+
+       if (!(fs->super->s_feature_compat & 
+             EXT2_FEATURE_COMPAT_RESIZE_INODE))
+               return 0;
+
+       retval = ext2fs_get_mem(fs->blocksize, &block_buf);
+       if (retval) goto errout;
+
+       retval = ext2fs_read_inode(fs, EXT2_RESIZE_INO, &inode);
+       if (retval) goto errout;
+
+       inode.i_blocks = fs->blocksize/512;
+
+       retval = ext2fs_write_inode(fs, EXT2_RESIZE_INO, &inode);
+       if (retval) goto errout;
+
+       if (!inode.i_block[EXT2_DIND_BLOCK]) {
+               /* 
+                * Avoid zeroing out block #0; that's rude.  This
+                * should never happen anyway since the filesystem
+                * should be fsck'ed and we assume it is consistent.
+                */
+               fprintf(stderr, 
+                       _("Should never happen resize inode corrupt!\n"));
+               exit(1);
+       }
+
+       memset(block_buf, 0, fs->blocksize);
+
+       retval = io_channel_write_blk(fs->io, inode.i_block[EXT2_DIND_BLOCK],
+                                     1, block_buf);
+       if (retval) goto errout;
+       
+       retval = ext2fs_create_resize_inode(fs);
+       if (retval)
+               goto errout;
+
+errout:
+       if (block_buf)
+               ext2fs_free_mem(&block_buf);
+       return retval;
+}
+
+/*
  * Finally, recalculate the summary information
  */
 static errcode_t ext2fs_calculate_summary_stats(ext2_filsys fs)