xfs: add version 3 inode format with CRCs

Add a new inode version with a larger core.  The primary objective is
to allow for a crc of the inode, and location information (uuid and ino)
to verify it was written in the right place.  We also extend it by:

	a creation time (for Samba);
	a changecount (for NFSv4);
	a flush sequence (in LSN format for recovery);
	an additional inode flags field; and
	some additional padding.

These additional fields are not implemented yet, but already laid
out in the structure.

[dchinner@redhat.com] Added LSN and flags field, some factoring and rework to
capture all the necessary information in the crc calculation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

1 files changed, 26 insertions, 0 deletions

diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index b8520b5c3a18..91129794aaec 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -150,13 +150,38 @@ typedef struct xfs_icdinode {
         __uint16_t      di_dmstate;     /* DMIG state info */
         __uint16_t      di_flags;       /* random flags, XFS_DIFLAG_... */
         __uint32_t      di_gen;         /* generation number */
+
+        /* di_next_unlinked is the only non-core field in the old dinode */
+        xfs_agino_t     di_next_unlinked;/* agi unlinked list ptr */
+
+        /* start of the extended dinode, writable fields */
+        __uint32_t      di_crc;         /* CRC of the inode */
+        __uint64_t      di_changecount; /* number of attribute changes */
+        xfs_lsn_t       di_lsn;         /* flush sequence */
+        __uint64_t      di_flags2;      /* more random flags */
+        __uint8_t       di_pad2[16];    /* more padding for future expansion */
+
+        /* fields only written to during inode creation */
+        xfs_ictimestamp_t di_crtime;    /* time created */
+        xfs_ino_t       di_ino;         /* inode number */
+        uuid_t          di_uuid;        /* UUID of the filesystem */
+
+        /* structure must be padded to 64 bit alignment */
 } xfs_icdinode_t;
 
+static inline uint xfs_icdinode_size(int version)
+{
+        if (version == 3)
+                return sizeof(struct xfs_icdinode);
+        return offsetof(struct xfs_icdinode, di_next_unlinked);
+}
+
 /*
  * Flags for xfs_ichgtime().
  */
 #define XFS_ICHGTIME_MOD        0x1     /* data fork modification timestamp */
 #define XFS_ICHGTIME_CHG        0x2     /* inode field change timestamp */
+#define XFS_ICHGTIME_CREATE     0x4     /* inode create timestamp */
 
 /*
  * Per-fork incore inode flags.
@@ -556,6 +581,7 @@ int		xfs_imap_to_bp(struct xfs_mount *, struct xfs_trans *,
                                struct xfs_buf **, uint, uint);
 int             xfs_iread(struct xfs_mount *, struct xfs_trans *,
                           struct xfs_inode *, uint);
+void            xfs_dinode_calc_crc(struct xfs_mount *, struct xfs_dinode *);
 void            xfs_dinode_to_disk(struct xfs_dinode *,
                                    struct xfs_icdinode *);
 void            xfs_idestroy_fork(struct xfs_inode *, int);