Patch: teach sysutils/grub about ext2fs with 256-byte inodes

[Josh Elsasser]

Here is a patch for grub taken from debian (who apparently took it
from redhat) to allow it to load linux kernels off newer ext2
filesystems which use 256-byte inodes.  I've been using this for a
while and forgot about it until I reinstalled grub after updating my
packages and noticed I couldn't boot linux anymore.

Index: Makefile
===================================================================
RCS file: /home/cvsync/openbsd/ports/sysutils/grub/Makefile,v
retrieving revision 1.4
diff -u -N Makefile
--- Makefile 5 Jun 2008 04:54:43 -0000 1.4
+++ Makefile 9 Jul 2009 19:48:49 -0000
@@ -5,7 +5,7 @@
 COMMENT= GRand Unified Bootloader
 
 DISTNAME= grub-0.97
-PKGNAME= ${DISTNAME}p1
+PKGNAME= ${DISTNAME}p2
 CATEGORIES= sysutils
 
 HOMEPAGE= http://www.gnu.org/software/grub/
Index: patches/patch-stage2_fsys_ext2fs_c
===================================================================
RCS file: patches/patch-stage2_fsys_ext2fs_c
diff -u -N patches/patch-stage2_fsys_ext2fs_c
--- /dev/null 7 Nov 2009 10:51:39 -0000
+++ patches/patch-stage2_fsys_ext2fs_c 16 May 2009 21:14:56 -0000
@@ -0,0 +1,104 @@
+$OpenBSD$
+
+Debian-Patch: ext3_256byte_inode.diff (From 0.97-47)
+
+Patch from Red Hat. See #463236, #463123 (and #491076 for the reviewed version)
+
+--- stage2/fsys_ext2fs.c.orig Sun Aug  8 11:19:18 2004
++++ stage2/fsys_ext2fs.c Sat May 16 14:13:02 2009
+@@ -79,7 +79,52 @@ struct ext2_super_block
+     __u32 s_rev_level; /* Revision level */
+     __u16 s_def_resuid; /* Default uid for reserved blocks */
+     __u16 s_def_resgid; /* Default gid for reserved blocks */
+-    __u32 s_reserved[235]; /* Padding to the end of the block */
++    /*
++     * These fields are for EXT2_DYNAMIC_REV superblocks only.
++     *
++     * Note: the difference between the compatible feature set and
++     * the incompatible feature set is that if there is a bit set
++     * in the incompatible feature set that the kernel doesn't
++     * know about, it should refuse to mount the filesystem.
++     *
++     * e2fsck's requirements are more strict; if it doesn't know
++     * about a feature in either the compatible or incompatible
++     * feature set, it must abort and not try to meddle with
++     * things it doesn't understand...
++     */
++    __u32 s_first_ino; /* First non-reserved inode */
++    __u16 s_inode_size; /* size of inode structure */
++    __u16 s_block_group_nr; /* block group # of this superblock */
++    __u32 s_feature_compat; /* compatible feature set */
++    __u32 s_feature_incompat; /* incompatible feature set */
++    __u32 s_feature_ro_compat; /* readonly-compatible feature set */
++    __u8  s_uuid[16]; /* 128-bit uuid for volume */
++    char  s_volume_name[16]; /* volume name */
++    char  s_last_mounted[64]; /* directory where last mounted */
++    __u32 s_algorithm_usage_bitmap; /* For compression */
++    /*
++     * Performance hints.  Directory preallocation should only
++     * happen if the EXT2_FEATURE_COMPAT_DIR_PREALLOC flag is on.
++     */
++    __u8  s_prealloc_blocks; /* Nr of blocks to try to preallocate*/
++    __u8  s_prealloc_dir_blocks; /* Nr to preallocate for dirs */
++    __u16 s_reserved_gdt_blocks;/* Per group table for online growth */
++    /*
++     * Journaling support valid if EXT2_FEATURE_COMPAT_HAS_JOURNAL set.
++     */
++    __u8 s_journal_uuid[16]; /* uuid of journal superblock */
++    __u32 s_journal_inum; /* inode number of journal file */
++    __u32 s_journal_dev; /* device number of journal file */
++    __u32 s_last_orphan; /* start of list of inodes to delete */
++    __u32 s_hash_seed[4]; /* HTREE hash seed */
++    __u8  s_def_hash_version; /* Default hash version to use */
++    __u8  s_jnl_backup_type; /* Default type of journal backup */
++    __u16 s_reserved_word_pad;
++    __u32 s_default_mount_opts;
++    __u32 s_first_meta_bg; /* First metablock group */
++    __u32 s_mkfs_time; /* When the filesystem was created */
++    __u32 s_jnl_blocks[17]; /* Backup of the journal inode */
++    __u32 s_reserved[172]; /* Padding to the end of the block */
+   };
+
+ struct ext2_group_desc
+@@ -218,6 +263,14 @@ struct ext2_dir_entry
+ #define EXT2_ADDR_PER_BLOCK(s)          (EXT2_BLOCK_SIZE(s) / sizeof (__u32))
+ #define EXT2_ADDR_PER_BLOCK_BITS(s) (log2(EXT2_ADDR_PER_BLOCK(s)))
+
++#define EXT2_GOOD_OLD_REV 0 /* The good old (original) format */
++#define EXT2_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */
++#define EXT2_GOOD_OLD_INODE_SIZE 128
++#define EXT2_INODE_SIZE(s) (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
++ EXT2_GOOD_OLD_INODE_SIZE : \
++ (s)->s_inode_size)
++#define EXT2_INODES_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s)/EXT2_INODE_SIZE(s))
++
+ /* linux/ext2_fs.h */
+ #define EXT2_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
+ /* kind of from ext2/super.c */
+@@ -553,7 +606,7 @@ ext2fs_dir (char *dirname)
+       gdp = GROUP_DESC;
+       ino_blk = gdp[desc].bg_inode_table +
+ (((current_ino - 1) % (SUPERBLOCK->s_inodes_per_group))
+- >> log2 (EXT2_BLOCK_SIZE (SUPERBLOCK) / sizeof (struct ext2_inode)));
++ >> log2 (EXT2_INODES_PER_BLOCK (SUPERBLOCK)));
+ #ifdef E2DEBUG
+       printf ("inode table fsblock=%d\n", ino_blk);
+ #endif /* E2DEBUG */
+@@ -565,13 +618,12 @@ ext2fs_dir (char *dirname)
+       /* reset indirect blocks! */
+       mapblock2 = mapblock1 = -1;
+
+-      raw_inode = INODE +
+- ((current_ino - 1)
+- & (EXT2_BLOCK_SIZE (SUPERBLOCK) / sizeof (struct ext2_inode) - 1));
++      raw_inode = (struct ext2_inode *)((char *)INODE +
++ ((current_ino - 1) & (EXT2_INODES_PER_BLOCK (SUPERBLOCK) - 1)) *
++ EXT2_INODE_SIZE (SUPERBLOCK));
+ #ifdef E2DEBUG
+       printf ("ipb=%d, sizeof(inode)=%d\n",
+-      (EXT2_BLOCK_SIZE (SUPERBLOCK) / sizeof (struct ext2_inode)),
+-      sizeof (struct ext2_inode));
++      EXT2_INODES_PER_BLOCK (SUPERBLOCK), EXT2_INODE_SIZE (SUPERBLOCK));
+       printf ("inode=%x, raw_inode=%x\n", INODE, raw_inode);
+       printf ("offset into inode table block=%d\n", (int) raw_inode - (int) INODE);
+       for (i = (unsigned char *) INODE; i <= (unsigned char *) raw_inode;