patch-2.4.25 linux-2.4.25/fs/ext2/super.c

• Lines: 77
• Date: 2004-02-18 05:36:31.000000000 -0800
• Orig file: linux-2.4.24/fs/ext2/super.c
• Orig date: 2002-11-28 15:53:15.000000000 -0800

diff -urN linux-2.4.24/fs/ext2/super.c linux-2.4.25/fs/ext2/super.c
@@ -397,14 +397,36 @@
 	return res;
 }
 
+static unsigned long descriptor_loc(struct super_block *sb,
+				    unsigned long logic_sb_block,
+				    int nr)
+{
+	struct ext2_sb_info *sbi = EXT2_SB(sb);
+	unsigned long bg, first_data_block, first_meta_bg;
+	int has_super = 0;
+	
+	first_data_block = le32_to_cpu(sbi->s_es->s_first_data_block);
+	first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
+
+	if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
+	    nr < first_meta_bg)
+		return (logic_sb_block + nr + 1);
+	bg = sbi->s_desc_per_block * nr;
+	if (ext2_bg_has_super(sb, bg))
+		has_super = 1;
+	return (first_data_block + has_super + (bg * sbi->s_blocks_per_group));
+}
+
 struct super_block * ext2_read_super (struct super_block * sb, void * data,
 				      int silent)
 {
 	struct buffer_head * bh;
+  	struct ext2_sb_info * sbi = EXT2_SB(sb);
 	struct ext2_super_block * es;
 	unsigned long sb_block = 1;
 	unsigned short resuid = EXT2_DEF_RESUID;
 	unsigned short resgid = EXT2_DEF_RESGID;
+	unsigned long block;
 	unsigned long logic_sb_block = 1;
 	unsigned long offset = 0;
 	kdev_t dev = sb->s_dev;
@@ -522,14 +544,16 @@
 	}
 
 	if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
-		sb->u.ext2_sb.s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
-		sb->u.ext2_sb.s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
+		sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
+		sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
 	} else {
-		sb->u.ext2_sb.s_inode_size = le16_to_cpu(es->s_inode_size);
-		sb->u.ext2_sb.s_first_ino = le32_to_cpu(es->s_first_ino);
-		if (sb->u.ext2_sb.s_inode_size != EXT2_GOOD_OLD_INODE_SIZE) {
+		sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
+		sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
+		if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
+		    (sbi->s_inode_size & (sbi->s_inode_size - 1)) ||
+		    (sbi->s_inode_size > blocksize)) {
 			printk ("EXT2-fs: unsupported inode size: %d\n",
-				sb->u.ext2_sb.s_inode_size);
+				sbi->s_inode_size);
 			goto failed_mount;
 		}
 	}
@@ -611,11 +635,12 @@
 		goto failed_mount;
 	}
 	for (i = 0; i < db_count; i++) {
-		sb->u.ext2_sb.s_group_desc[i] = sb_bread(sb, logic_sb_block + i + 1);
-		if (!sb->u.ext2_sb.s_group_desc[i]) {
+		block = descriptor_loc(sb, logic_sb_block, i);
+		sbi->s_group_desc[i] = sb_bread(sb, block);
+		if (!sbi->s_group_desc[i]) {
 			for (j = 0; j < i; j++)
-				brelse (sb->u.ext2_sb.s_group_desc[j]);
-			kfree(sb->u.ext2_sb.s_group_desc);
+				brelse (sbi->s_group_desc[j]);
+			kfree(sbi->s_group_desc);
 			printk ("EXT2-fs: unable to read group descriptors\n");
 			goto failed_mount;
 		}