[PATCH] ext2: fix mounts at 16T

Signed-off-by: Eric Sandeen <esandeen@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/fs/ext2/super.c b/fs/ext2/super.c
index 4286ff6..d978d3f 100644 (file)
--- a/fs/ext2/super.c
+++ b/fs/ext2/super.c
@@ -544,17 +544,24 @@ static int ext2_check_descriptors (struct super_block * sb)
        int i;
        int desc_block = 0;
        struct ext2_sb_info *sbi = EXT2_SB(sb);
-       unsigned long block = le32_to_cpu(sbi->s_es->s_first_data_block);
+       unsigned long first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
+       unsigned long last_block;
        struct ext2_group_desc * gdp = NULL;
 
        ext2_debug ("Checking group descriptors");
 
        for (i = 0; i < sbi->s_groups_count; i++)
        {
+               if (i == sbi->s_groups_count - 1)
+                       last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1;
+               else
+                       last_block = first_block +
+                               (EXT2_BLOCKS_PER_GROUP(sb) - 1);
+
                if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0)
                        gdp = (struct ext2_group_desc *) sbi->s_group_desc[desc_block++]->b_data;
-               if (le32_to_cpu(gdp->bg_block_bitmap) < block ||
-                   le32_to_cpu(gdp->bg_block_bitmap) >= block + EXT2_BLOCKS_PER_GROUP(sb))
+               if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||
+                   le32_to_cpu(gdp->bg_block_bitmap) > last_block)
                {
                        ext2_error (sb, "ext2_check_descriptors",
                                    "Block bitmap for group %d"
@@ -562,8 +569,8 @@ static int ext2_check_descriptors (struct super_block * sb)
                                    i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
                        return 0;
                }
-               if (le32_to_cpu(gdp->bg_inode_bitmap) < block ||
-                   le32_to_cpu(gdp->bg_inode_bitmap) >= block + EXT2_BLOCKS_PER_GROUP(sb))
+               if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||
+                   le32_to_cpu(gdp->bg_inode_bitmap) > last_block)
                {
                        ext2_error (sb, "ext2_check_descriptors",
                                    "Inode bitmap for group %d"
@@ -571,9 +578,9 @@ static int ext2_check_descriptors (struct super_block * sb)
                                    i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
                        return 0;
                }
-               if (le32_to_cpu(gdp->bg_inode_table) < block ||
-                   le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group >=
-                   block + EXT2_BLOCKS_PER_GROUP(sb))
+               if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
+                   le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group >
+                   last_block)
                {
                        ext2_error (sb, "ext2_check_descriptors",
                                    "Inode table for group %d"
@@ -581,7 +588,7 @@ static int ext2_check_descriptors (struct super_block * sb)
                                    i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
                        return 0;
                }
-               block += EXT2_BLOCKS_PER_GROUP(sb);
+               first_block += EXT2_BLOCKS_PER_GROUP(sb);
                gdp++;
        }
        return 1;
@@ -861,10 +868,9 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent)
 
        if (EXT2_BLOCKS_PER_GROUP(sb) == 0)
                goto cantfind_ext2;
-       sbi->s_groups_count = (le32_to_cpu(es->s_blocks_count) -
-                                       le32_to_cpu(es->s_first_data_block) +
-                                      EXT2_BLOCKS_PER_GROUP(sb) - 1) /
-                                      EXT2_BLOCKS_PER_GROUP(sb);
+       sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
+                               le32_to_cpu(es->s_first_data_block) - 1)
+                                       / EXT2_BLOCKS_PER_GROUP(sb)) + 1;
        db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
                   EXT2_DESC_PER_BLOCK(sb);
        sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL);