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authorAl Viro <viro@zeniv.linux.org.uk>2012-03-24 00:45:51 +0400
committerAl Viro <viro@zeniv.linux.org.uk>2012-04-01 00:03:16 +0400
commitf7699f2b0114fcd0ea5ad5f8aa2142f1bcc27fd0 (patch)
tree054330e3e093e8b19eaeb4a60e93b936cde22266 /fs/ext2/ext2.h
parent39429c5e4a2c56a39c9a1c9bdad54431c63104b0 (diff)
downloadlinux-f7699f2b0114fcd0ea5ad5f8aa2142f1bcc27fd0.tar.xz
migrate ext2_fs.h guts to fs/ext2/ext2.h
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs/ext2/ext2.h')
-rw-r--r--fs/ext2/ext2.h631
1 files changed, 631 insertions, 0 deletions
diff --git a/fs/ext2/ext2.h b/fs/ext2/ext2.h
index 75ad433c6691..0b2b4db5bdcd 100644
--- a/fs/ext2/ext2.h
+++ b/fs/ext2/ext2.h
@@ -1,5 +1,636 @@
+/*
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ *
+ * from
+ *
+ * linux/include/linux/minix_fs.h
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ */
#include <linux/fs.h>
#include <linux/ext2_fs.h>
+#include <linux/blockgroup_lock.h>
+#include <linux/percpu_counter.h>
+#include <linux/rbtree.h>
+
+/* XXX Here for now... not interested in restructing headers JUST now */
+
+/* data type for block offset of block group */
+typedef int ext2_grpblk_t;
+
+/* data type for filesystem-wide blocks number */
+typedef unsigned long ext2_fsblk_t;
+
+#define E2FSBLK "%lu"
+
+struct ext2_reserve_window {
+ ext2_fsblk_t _rsv_start; /* First byte reserved */
+ ext2_fsblk_t _rsv_end; /* Last byte reserved or 0 */
+};
+
+struct ext2_reserve_window_node {
+ struct rb_node rsv_node;
+ __u32 rsv_goal_size;
+ __u32 rsv_alloc_hit;
+ struct ext2_reserve_window rsv_window;
+};
+
+struct ext2_block_alloc_info {
+ /* information about reservation window */
+ struct ext2_reserve_window_node rsv_window_node;
+ /*
+ * was i_next_alloc_block in ext2_inode_info
+ * is the logical (file-relative) number of the
+ * most-recently-allocated block in this file.
+ * We use this for detecting linearly ascending allocation requests.
+ */
+ __u32 last_alloc_logical_block;
+ /*
+ * Was i_next_alloc_goal in ext2_inode_info
+ * is the *physical* companion to i_next_alloc_block.
+ * it the the physical block number of the block which was most-recentl
+ * allocated to this file. This give us the goal (target) for the next
+ * allocation when we detect linearly ascending requests.
+ */
+ ext2_fsblk_t last_alloc_physical_block;
+};
+
+#define rsv_start rsv_window._rsv_start
+#define rsv_end rsv_window._rsv_end
+
+/*
+ * second extended-fs super-block data in memory
+ */
+struct ext2_sb_info {
+ unsigned long s_frag_size; /* Size of a fragment in bytes */
+ unsigned long s_frags_per_block;/* Number of fragments per block */
+ unsigned long s_inodes_per_block;/* Number of inodes per block */
+ unsigned long s_frags_per_group;/* Number of fragments in a group */
+ unsigned long s_blocks_per_group;/* Number of blocks in a group */
+ unsigned long s_inodes_per_group;/* Number of inodes in a group */
+ unsigned long s_itb_per_group; /* Number of inode table blocks per group */
+ unsigned long s_gdb_count; /* Number of group descriptor blocks */
+ unsigned long s_desc_per_block; /* Number of group descriptors per block */
+ unsigned long s_groups_count; /* Number of groups in the fs */
+ unsigned long s_overhead_last; /* Last calculated overhead */
+ unsigned long s_blocks_last; /* Last seen block count */
+ struct buffer_head * s_sbh; /* Buffer containing the super block */
+ struct ext2_super_block * s_es; /* Pointer to the super block in the buffer */
+ struct buffer_head ** s_group_desc;
+ unsigned long s_mount_opt;
+ unsigned long s_sb_block;
+ uid_t s_resuid;
+ gid_t s_resgid;
+ unsigned short s_mount_state;
+ unsigned short s_pad;
+ int s_addr_per_block_bits;
+ int s_desc_per_block_bits;
+ int s_inode_size;
+ int s_first_ino;
+ spinlock_t s_next_gen_lock;
+ u32 s_next_generation;
+ unsigned long s_dir_count;
+ u8 *s_debts;
+ struct percpu_counter s_freeblocks_counter;
+ struct percpu_counter s_freeinodes_counter;
+ struct percpu_counter s_dirs_counter;
+ struct blockgroup_lock *s_blockgroup_lock;
+ /* root of the per fs reservation window tree */
+ spinlock_t s_rsv_window_lock;
+ struct rb_root s_rsv_window_root;
+ struct ext2_reserve_window_node s_rsv_window_head;
+ /*
+ * s_lock protects against concurrent modifications of s_mount_state,
+ * s_blocks_last, s_overhead_last and the content of superblock's
+ * buffer pointed to by sbi->s_es.
+ *
+ * Note: It is used in ext2_show_options() to provide a consistent view
+ * of the mount options.
+ */
+ spinlock_t s_lock;
+};
+
+static inline spinlock_t *
+sb_bgl_lock(struct ext2_sb_info *sbi, unsigned int block_group)
+{
+ return bgl_lock_ptr(sbi->s_blockgroup_lock, block_group);
+}
+
+/*
+ * Define EXT2FS_DEBUG to produce debug messages
+ */
+#undef EXT2FS_DEBUG
+
+/*
+ * Define EXT2_RESERVATION to reserve data blocks for expanding files
+ */
+#define EXT2_DEFAULT_RESERVE_BLOCKS 8
+/*max window size: 1024(direct blocks) + 3([t,d]indirect blocks) */
+#define EXT2_MAX_RESERVE_BLOCKS 1027
+#define EXT2_RESERVE_WINDOW_NOT_ALLOCATED 0
+/*
+ * The second extended file system version
+ */
+#define EXT2FS_DATE "95/08/09"
+#define EXT2FS_VERSION "0.5b"
+
+/*
+ * Debug code
+ */
+#ifdef EXT2FS_DEBUG
+# define ext2_debug(f, a...) { \
+ printk ("EXT2-fs DEBUG (%s, %d): %s:", \
+ __FILE__, __LINE__, __func__); \
+ printk (f, ## a); \
+ }
+#else
+# define ext2_debug(f, a...) /**/
+#endif
+
+/*
+ * Special inode numbers
+ */
+#define EXT2_BAD_INO 1 /* Bad blocks inode */
+#define EXT2_ROOT_INO 2 /* Root inode */
+#define EXT2_BOOT_LOADER_INO 5 /* Boot loader inode */
+#define EXT2_UNDEL_DIR_INO 6 /* Undelete directory inode */
+
+/* First non-reserved inode for old ext2 filesystems */
+#define EXT2_GOOD_OLD_FIRST_INO 11
+
+static inline struct ext2_sb_info *EXT2_SB(struct super_block *sb)
+{
+ return sb->s_fs_info;
+}
+
+/*
+ * Macro-instructions used to manage several block sizes
+ */
+#define EXT2_MIN_BLOCK_SIZE 1024
+#define EXT2_MAX_BLOCK_SIZE 4096
+#define EXT2_MIN_BLOCK_LOG_SIZE 10
+#define EXT2_BLOCK_SIZE(s) ((s)->s_blocksize)
+#define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (__u32))
+#define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_blocksize_bits)
+#define EXT2_ADDR_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_addr_per_block_bits)
+#define EXT2_INODE_SIZE(s) (EXT2_SB(s)->s_inode_size)
+#define EXT2_FIRST_INO(s) (EXT2_SB(s)->s_first_ino)
+
+/*
+ * Macro-instructions used to manage fragments
+ */
+#define EXT2_MIN_FRAG_SIZE 1024
+#define EXT2_MAX_FRAG_SIZE 4096
+#define EXT2_MIN_FRAG_LOG_SIZE 10
+#define EXT2_FRAG_SIZE(s) (EXT2_SB(s)->s_frag_size)
+#define EXT2_FRAGS_PER_BLOCK(s) (EXT2_SB(s)->s_frags_per_block)
+
+/*
+ * Structure of a blocks group descriptor
+ */
+struct ext2_group_desc
+{
+ __le32 bg_block_bitmap; /* Blocks bitmap block */
+ __le32 bg_inode_bitmap; /* Inodes bitmap block */
+ __le32 bg_inode_table; /* Inodes table block */
+ __le16 bg_free_blocks_count; /* Free blocks count */
+ __le16 bg_free_inodes_count; /* Free inodes count */
+ __le16 bg_used_dirs_count; /* Directories count */
+ __le16 bg_pad;
+ __le32 bg_reserved[3];
+};
+
+/*
+ * Macro-instructions used to manage group descriptors
+ */
+#define EXT2_BLOCKS_PER_GROUP(s) (EXT2_SB(s)->s_blocks_per_group)
+#define EXT2_DESC_PER_BLOCK(s) (EXT2_SB(s)->s_desc_per_block)
+#define EXT2_INODES_PER_GROUP(s) (EXT2_SB(s)->s_inodes_per_group)
+#define EXT2_DESC_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_desc_per_block_bits)
+
+/*
+ * Constants relative to the data blocks
+ */
+#define EXT2_NDIR_BLOCKS 12
+#define EXT2_IND_BLOCK EXT2_NDIR_BLOCKS
+#define EXT2_DIND_BLOCK (EXT2_IND_BLOCK + 1)
+#define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1)
+#define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1)
+
+/*
+ * Inode flags (GETFLAGS/SETFLAGS)
+ */
+#define EXT2_SECRM_FL FS_SECRM_FL /* Secure deletion */
+#define EXT2_UNRM_FL FS_UNRM_FL /* Undelete */
+#define EXT2_COMPR_FL FS_COMPR_FL /* Compress file */
+#define EXT2_SYNC_FL FS_SYNC_FL /* Synchronous updates */
+#define EXT2_IMMUTABLE_FL FS_IMMUTABLE_FL /* Immutable file */
+#define EXT2_APPEND_FL FS_APPEND_FL /* writes to file may only append */
+#define EXT2_NODUMP_FL FS_NODUMP_FL /* do not dump file */
+#define EXT2_NOATIME_FL FS_NOATIME_FL /* do not update atime */
+/* Reserved for compression usage... */
+#define EXT2_DIRTY_FL FS_DIRTY_FL
+#define EXT2_COMPRBLK_FL FS_COMPRBLK_FL /* One or more compressed clusters */
+#define EXT2_NOCOMP_FL FS_NOCOMP_FL /* Don't compress */
+#define EXT2_ECOMPR_FL FS_ECOMPR_FL /* Compression error */
+/* End compression flags --- maybe not all used */
+#define EXT2_BTREE_FL FS_BTREE_FL /* btree format dir */
+#define EXT2_INDEX_FL FS_INDEX_FL /* hash-indexed directory */
+#define EXT2_IMAGIC_FL FS_IMAGIC_FL /* AFS directory */
+#define EXT2_JOURNAL_DATA_FL FS_JOURNAL_DATA_FL /* Reserved for ext3 */
+#define EXT2_NOTAIL_FL FS_NOTAIL_FL /* file tail should not be merged */
+#define EXT2_DIRSYNC_FL FS_DIRSYNC_FL /* dirsync behaviour (directories only) */
+#define EXT2_TOPDIR_FL FS_TOPDIR_FL /* Top of directory hierarchies*/
+#define EXT2_RESERVED_FL FS_RESERVED_FL /* reserved for ext2 lib */
+
+#define EXT2_FL_USER_VISIBLE FS_FL_USER_VISIBLE /* User visible flags */
+#define EXT2_FL_USER_MODIFIABLE FS_FL_USER_MODIFIABLE /* User modifiable flags */
+
+/* Flags that should be inherited by new inodes from their parent. */
+#define EXT2_FL_INHERITED (EXT2_SECRM_FL | EXT2_UNRM_FL | EXT2_COMPR_FL |\
+ EXT2_SYNC_FL | EXT2_NODUMP_FL |\
+ EXT2_NOATIME_FL | EXT2_COMPRBLK_FL |\
+ EXT2_NOCOMP_FL | EXT2_JOURNAL_DATA_FL |\
+ EXT2_NOTAIL_FL | EXT2_DIRSYNC_FL)
+
+/* Flags that are appropriate for regular files (all but dir-specific ones). */
+#define EXT2_REG_FLMASK (~(EXT2_DIRSYNC_FL | EXT2_TOPDIR_FL))
+
+/* Flags that are appropriate for non-directories/regular files. */
+#define EXT2_OTHER_FLMASK (EXT2_NODUMP_FL | EXT2_NOATIME_FL)
+
+/* Mask out flags that are inappropriate for the given type of inode. */
+static inline __u32 ext2_mask_flags(umode_t mode, __u32 flags)
+{
+ if (S_ISDIR(mode))
+ return flags;
+ else if (S_ISREG(mode))
+ return flags & EXT2_REG_FLMASK;
+ else
+ return flags & EXT2_OTHER_FLMASK;
+}
+
+/*
+ * ioctl commands
+ */
+#define EXT2_IOC_GETFLAGS FS_IOC_GETFLAGS
+#define EXT2_IOC_SETFLAGS FS_IOC_SETFLAGS
+#define EXT2_IOC_GETVERSION FS_IOC_GETVERSION
+#define EXT2_IOC_SETVERSION FS_IOC_SETVERSION
+#define EXT2_IOC_GETRSVSZ _IOR('f', 5, long)
+#define EXT2_IOC_SETRSVSZ _IOW('f', 6, long)
+
+/*
+ * ioctl commands in 32 bit emulation
+ */
+#define EXT2_IOC32_GETFLAGS FS_IOC32_GETFLAGS
+#define EXT2_IOC32_SETFLAGS FS_IOC32_SETFLAGS
+#define EXT2_IOC32_GETVERSION FS_IOC32_GETVERSION
+#define EXT2_IOC32_SETVERSION FS_IOC32_SETVERSION
+
+/*
+ * Structure of an inode on the disk
+ */
+struct ext2_inode {
+ __le16 i_mode; /* File mode */
+ __le16 i_uid; /* Low 16 bits of Owner Uid */
+ __le32 i_size; /* Size in bytes */
+ __le32 i_atime; /* Access time */
+ __le32 i_ctime; /* Creation time */
+ __le32 i_mtime; /* Modification time */
+ __le32 i_dtime; /* Deletion Time */
+ __le16 i_gid; /* Low 16 bits of Group Id */
+ __le16 i_links_count; /* Links count */
+ __le32 i_blocks; /* Blocks count */
+ __le32 i_flags; /* File flags */
+ union {
+ struct {
+ __le32 l_i_reserved1;
+ } linux1;
+ struct {
+ __le32 h_i_translator;
+ } hurd1;
+ struct {
+ __le32 m_i_reserved1;
+ } masix1;
+ } osd1; /* OS dependent 1 */
+ __le32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
+ __le32 i_generation; /* File version (for NFS) */
+ __le32 i_file_acl; /* File ACL */
+ __le32 i_dir_acl; /* Directory ACL */
+ __le32 i_faddr; /* Fragment address */
+ union {
+ struct {
+ __u8 l_i_frag; /* Fragment number */
+ __u8 l_i_fsize; /* Fragment size */
+ __u16 i_pad1;
+ __le16 l_i_uid_high; /* these 2 fields */
+ __le16 l_i_gid_high; /* were reserved2[0] */
+ __u32 l_i_reserved2;
+ } linux2;
+ struct {
+ __u8 h_i_frag; /* Fragment number */
+ __u8 h_i_fsize; /* Fragment size */
+ __le16 h_i_mode_high;
+ __le16 h_i_uid_high;
+ __le16 h_i_gid_high;
+ __le32 h_i_author;
+ } hurd2;
+ struct {
+ __u8 m_i_frag; /* Fragment number */
+ __u8 m_i_fsize; /* Fragment size */
+ __u16 m_pad1;
+ __u32 m_i_reserved2[2];
+ } masix2;
+ } osd2; /* OS dependent 2 */
+};
+
+#define i_size_high i_dir_acl
+
+#define i_reserved1 osd1.linux1.l_i_reserved1
+#define i_frag osd2.linux2.l_i_frag
+#define i_fsize osd2.linux2.l_i_fsize
+#define i_uid_low i_uid
+#define i_gid_low i_gid
+#define i_uid_high osd2.linux2.l_i_uid_high
+#define i_gid_high osd2.linux2.l_i_gid_high
+#define i_reserved2 osd2.linux2.l_i_reserved2
+
+/*
+ * File system states
+ */
+#define EXT2_VALID_FS 0x0001 /* Unmounted cleanly */
+#define EXT2_ERROR_FS 0x0002 /* Errors detected */
+
+/*
+ * Mount flags
+ */
+#define EXT2_MOUNT_CHECK 0x000001 /* Do mount-time checks */
+#define EXT2_MOUNT_OLDALLOC 0x000002 /* Don't use the new Orlov allocator */
+#define EXT2_MOUNT_GRPID 0x000004 /* Create files with directory's group */
+#define EXT2_MOUNT_DEBUG 0x000008 /* Some debugging messages */
+#define EXT2_MOUNT_ERRORS_CONT 0x000010 /* Continue on errors */
+#define EXT2_MOUNT_ERRORS_RO 0x000020 /* Remount fs ro on errors */
+#define EXT2_MOUNT_ERRORS_PANIC 0x000040 /* Panic on errors */
+#define EXT2_MOUNT_MINIX_DF 0x000080 /* Mimics the Minix statfs */
+#define EXT2_MOUNT_NOBH 0x000100 /* No buffer_heads */
+#define EXT2_MOUNT_NO_UID32 0x000200 /* Disable 32-bit UIDs */
+#define EXT2_MOUNT_XATTR_USER 0x004000 /* Extended user attributes */
+#define EXT2_MOUNT_POSIX_ACL 0x008000 /* POSIX Access Control Lists */
+#define EXT2_MOUNT_XIP 0x010000 /* Execute in place */
+#define EXT2_MOUNT_USRQUOTA 0x020000 /* user quota */
+#define EXT2_MOUNT_GRPQUOTA 0x040000 /* group quota */
+#define EXT2_MOUNT_RESERVATION 0x080000 /* Preallocation */
+
+
+#define clear_opt(o, opt) o &= ~EXT2_MOUNT_##opt
+#define set_opt(o, opt) o |= EXT2_MOUNT_##opt
+#define test_opt(sb, opt) (EXT2_SB(sb)->s_mount_opt & \
+ EXT2_MOUNT_##opt)
+/*
+ * Maximal mount counts between two filesystem checks
+ */
+#define EXT2_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */
+#define EXT2_DFL_CHECKINTERVAL 0 /* Don't use interval check */
+
+/*
+ * Behaviour when detecting errors
+ */
+#define EXT2_ERRORS_CONTINUE 1 /* Continue execution */
+#define EXT2_ERRORS_RO 2 /* Remount fs read-only */
+#define EXT2_ERRORS_PANIC 3 /* Panic */
+#define EXT2_ERRORS_DEFAULT EXT2_ERRORS_CONTINUE
+
+/*
+ * Structure of the super block
+ */
+struct ext2_super_block {
+ __le32 s_inodes_count; /* Inodes count */
+ __le32 s_blocks_count; /* Blocks count */
+ __le32 s_r_blocks_count; /* Reserved blocks count */
+ __le32 s_free_blocks_count; /* Free blocks count */
+ __le32 s_free_inodes_count; /* Free inodes count */
+ __le32 s_first_data_block; /* First Data Block */
+ __le32 s_log_block_size; /* Block size */
+ __le32 s_log_frag_size; /* Fragment size */
+ __le32 s_blocks_per_group; /* # Blocks per group */
+ __le32 s_frags_per_group; /* # Fragments per group */
+ __le32 s_inodes_per_group; /* # Inodes per group */
+ __le32 s_mtime; /* Mount time */
+ __le32 s_wtime; /* Write time */
+ __le16 s_mnt_count; /* Mount count */
+ __le16 s_max_mnt_count; /* Maximal mount count */
+ __le16 s_magic; /* Magic signature */
+ __le16 s_state; /* File system state */
+ __le16 s_errors; /* Behaviour when detecting errors */
+ __le16 s_minor_rev_level; /* minor revision level */
+ __le32 s_lastcheck; /* time of last check */
+ __le32 s_checkinterval; /* max. time between checks */
+ __le32 s_creator_os; /* OS */
+ __le32 s_rev_level; /* Revision level */
+ __le16 s_def_resuid; /* Default uid for reserved blocks */
+ __le16 s_def_resgid; /* Default gid for reserved blocks */
+ /*
+ * 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...
+ */
+ __le32 s_first_ino; /* First non-reserved inode */
+ __le16 s_inode_size; /* size of inode structure */
+ __le16 s_block_group_nr; /* block group # of this superblock */
+ __le32 s_feature_compat; /* compatible feature set */
+ __le32 s_feature_incompat; /* incompatible feature set */
+ __le32 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 */
+ __le32 s_algorithm_usage_bitmap; /* For compression */
+ /*
+ * Performance hints. Directory preallocation should only
+ * happen if the EXT2_COMPAT_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_padding1;
+ /*
+ * Journaling support valid if EXT3_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_reserved_char_pad;
+ __u16 s_reserved_word_pad;
+ __le32 s_default_mount_opts;
+ __le32 s_first_meta_bg; /* First metablock block group */
+ __u32 s_reserved[190]; /* Padding to the end of the block */
+};
+
+/*
+ * Codes for operating systems
+ */
+#define EXT2_OS_LINUX 0
+#define EXT2_OS_HURD 1
+#define EXT2_OS_MASIX 2
+#define EXT2_OS_FREEBSD 3
+#define EXT2_OS_LITES 4
+
+/*
+ * Revision levels
+ */
+#define EXT2_GOOD_OLD_REV 0 /* The good old (original) format */
+#define EXT2_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */
+
+#define EXT2_CURRENT_REV EXT2_GOOD_OLD_REV
+#define EXT2_MAX_SUPP_REV EXT2_DYNAMIC_REV
+
+#define EXT2_GOOD_OLD_INODE_SIZE 128
+
+/*
+ * Feature set definitions
+ */
+
+#define EXT2_HAS_COMPAT_FEATURE(sb,mask) \
+ ( EXT2_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask) )
+#define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \
+ ( EXT2_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask) )
+#define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \
+ ( EXT2_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask) )
+#define EXT2_SET_COMPAT_FEATURE(sb,mask) \
+ EXT2_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
+#define EXT2_SET_RO_COMPAT_FEATURE(sb,mask) \
+ EXT2_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
+#define EXT2_SET_INCOMPAT_FEATURE(sb,mask) \
+ EXT2_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
+#define EXT2_CLEAR_COMPAT_FEATURE(sb,mask) \
+ EXT2_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
+#define EXT2_CLEAR_RO_COMPAT_FEATURE(sb,mask) \
+ EXT2_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
+#define EXT2_CLEAR_INCOMPAT_FEATURE(sb,mask) \
+ EXT2_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
+
+#define EXT2_FEATURE_COMPAT_DIR_PREALLOC 0x0001
+#define EXT2_FEATURE_COMPAT_IMAGIC_INODES 0x0002
+#define EXT3_FEATURE_COMPAT_HAS_JOURNAL 0x0004
+#define EXT2_FEATURE_COMPAT_EXT_ATTR 0x0008
+#define EXT2_FEATURE_COMPAT_RESIZE_INO 0x0010
+#define EXT2_FEATURE_COMPAT_DIR_INDEX 0x0020
+#define EXT2_FEATURE_COMPAT_ANY 0xffffffff
+
+#define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
+#define EXT2_FEATURE_RO_COMPAT_LARGE_FILE 0x0002
+#define EXT2_FEATURE_RO_COMPAT_BTREE_DIR 0x0004
+#define EXT2_FEATURE_RO_COMPAT_ANY 0xffffffff
+
+#define EXT2_FEATURE_INCOMPAT_COMPRESSION 0x0001
+#define EXT2_FEATURE_INCOMPAT_FILETYPE 0x0002
+#define EXT3_FEATURE_INCOMPAT_RECOVER 0x0004
+#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008
+#define EXT2_FEATURE_INCOMPAT_META_BG 0x0010
+#define EXT2_FEATURE_INCOMPAT_ANY 0xffffffff
+
+#define EXT2_FEATURE_COMPAT_SUPP EXT2_FEATURE_COMPAT_EXT_ATTR
+#define EXT2_FEATURE_INCOMPAT_SUPP (EXT2_FEATURE_INCOMPAT_FILETYPE| \
+ EXT2_FEATURE_INCOMPAT_META_BG)
+#define EXT2_FEATURE_RO_COMPAT_SUPP (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
+ EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
+ EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
+#define EXT2_FEATURE_RO_COMPAT_UNSUPPORTED ~EXT2_FEATURE_RO_COMPAT_SUPP
+#define EXT2_FEATURE_INCOMPAT_UNSUPPORTED ~EXT2_FEATURE_INCOMPAT_SUPP
+
+/*
+ * Default values for user and/or group using reserved blocks
+ */
+#define EXT2_DEF_RESUID 0
+#define EXT2_DEF_RESGID 0
+
+/*
+ * Default mount options
+ */
+#define EXT2_DEFM_DEBUG 0x0001
+#define EXT2_DEFM_BSDGROUPS 0x0002
+#define EXT2_DEFM_XATTR_USER 0x0004
+#define EXT2_DEFM_ACL 0x0008
+#define EXT2_DEFM_UID16 0x0010
+ /* Not used by ext2, but reserved for use by ext3 */
+#define EXT3_DEFM_JMODE 0x0060
+#define EXT3_DEFM_JMODE_DATA 0x0020
+#define EXT3_DEFM_JMODE_ORDERED 0x0040
+#define EXT3_DEFM_JMODE_WBACK 0x0060
+
+/*
+ * Structure of a directory entry
+ */
+
+struct ext2_dir_entry {
+ __le32 inode; /* Inode number */
+ __le16 rec_len; /* Directory entry length */
+ __le16 name_len; /* Name length */
+ char name[]; /* File name, up to EXT2_NAME_LEN */
+};
+
+/*
+ * The new version of the directory entry. Since EXT2 structures are
+ * stored in intel byte order, and the name_len field could never be
+ * bigger than 255 chars, it's safe to reclaim the extra byte for the
+ * file_type field.
+ */
+struct ext2_dir_entry_2 {
+ __le32 inode; /* Inode number */
+ __le16 rec_len; /* Directory entry length */
+ __u8 name_len; /* Name length */
+ __u8 file_type;
+ char name[]; /* File name, up to EXT2_NAME_LEN */
+};
+
+/*
+ * Ext2 directory file types. Only the low 3 bits are used. The
+ * other bits are reserved for now.
+ */
+enum {
+ EXT2_FT_UNKNOWN = 0,
+ EXT2_FT_REG_FILE = 1,
+ EXT2_FT_DIR = 2,
+ EXT2_FT_CHRDEV = 3,
+ EXT2_FT_BLKDEV = 4,
+ EXT2_FT_FIFO = 5,
+ EXT2_FT_SOCK = 6,
+ EXT2_FT_SYMLINK = 7,
+ EXT2_FT_MAX
+};
+
+/*
+ * EXT2_DIR_PAD defines the directory entries boundaries
+ *
+ * NOTE: It must be a multiple of 4
+ */
+#define EXT2_DIR_PAD 4
+#define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1)
+#define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & \
+ ~EXT2_DIR_ROUND)
+#define EXT2_MAX_REC_LEN ((1<<16)-1)
+
+static inline void verify_offsets(void)
+{
+#define A(x,y) BUILD_BUG_ON(x != offsetof(struct ext2_super_block, y));
+ A(EXT2_SB_MAGIC_OFFSET, s_magic);
+ A(EXT2_SB_BLOCKS_OFFSET, s_blocks_count);
+ A(EXT2_SB_BSIZE_OFFSET, s_log_block_size);
+#undef A
+}
/*
* ext2 mount options