/*
* Superblock - in core version. Must match the ondisk version below.
+ * Must be padded to 64 bit alignment.
*/
typedef struct xfs_sb {
__uint32_t sb_magicnum; /* magic number == XFS_SB_MAGIC */
__uint16_t sb_logsectsize; /* sector size for the log, bytes */
__uint32_t sb_logsunit; /* stripe unit size for the log */
__uint32_t sb_features2; /* additional feature bits */
+
+ /*
+ * bad features2 field as a result of failing to pad the sb
+ * structure to 64 bits. Some machines will be using this field
+ * for features2 bits. Easiest just to mark it bad and not use
+ * it for anything else.
+ */
+ __uint32_t sb_bad_features2;
+
+ /* must be padded to 64 bit alignment */
} xfs_sb_t;
/*
- * Superblock - on disk version. Must match the in core version below.
+ * Superblock - on disk version. Must match the in core version above.
+ * Must be padded to 64 bit alignment.
*/
typedef struct xfs_dsb {
__be32 sb_magicnum; /* magic number == XFS_SB_MAGIC */
__be16 sb_logsectsize; /* sector size for the log, bytes */
__be32 sb_logsunit; /* stripe unit size for the log */
__be32 sb_features2; /* additional feature bits */
+ /*
+ * bad features2 field as a result of failing to pad the sb
+ * structure to 64 bits. Some machines will be using this field
+ * for features2 bits. Easiest just to mark it bad and not use
+ * it for anything else.
+ */
+ __be32 sb_bad_features2;
+
+ /* must be padded to 64 bit alignment */
} xfs_dsb_t;
/*
XFS_SBS_GQUOTINO, XFS_SBS_QFLAGS, XFS_SBS_FLAGS, XFS_SBS_SHARED_VN,
XFS_SBS_INOALIGNMT, XFS_SBS_UNIT, XFS_SBS_WIDTH, XFS_SBS_DIRBLKLOG,
XFS_SBS_LOGSECTLOG, XFS_SBS_LOGSECTSIZE, XFS_SBS_LOGSUNIT,
- XFS_SBS_FEATURES2,
+ XFS_SBS_FEATURES2, XFS_SBS_BAD_FEATURES2,
XFS_SBS_FIELDCOUNT
} xfs_sb_field_t;
#define XFS_SB_IFREE XFS_SB_MVAL(IFREE)
#define XFS_SB_FDBLOCKS XFS_SB_MVAL(FDBLOCKS)
#define XFS_SB_FEATURES2 XFS_SB_MVAL(FEATURES2)
+#define XFS_SB_BAD_FEATURES2 XFS_SB_MVAL(BAD_FEATURES2)
#define XFS_SB_NUM_BITS ((int)XFS_SBS_FIELDCOUNT)
#define XFS_SB_ALL_BITS ((1LL << XFS_SB_NUM_BITS) - 1)
#define XFS_SB_MOD_BITS \
(XFS_SB_UUID | XFS_SB_ROOTINO | XFS_SB_RBMINO | XFS_SB_RSUMINO | \
XFS_SB_VERSIONNUM | XFS_SB_UQUOTINO | XFS_SB_GQUOTINO | \
XFS_SB_QFLAGS | XFS_SB_SHARED_VN | XFS_SB_UNIT | XFS_SB_WIDTH | \
- XFS_SB_ICOUNT | XFS_SB_IFREE | XFS_SB_FDBLOCKS | XFS_SB_FEATURES2)
+ XFS_SB_ICOUNT | XFS_SB_IFREE | XFS_SB_FDBLOCKS | XFS_SB_FEATURES2 | \
+ XFS_SB_BAD_FEATURES2)
/*
}
#endif /* __KERNEL__ */
+/*
+ * Detect a mismatched features2 field. Older kernels read/wrote
+ * this into the wrong slot, so to be safe we keep them in sync.
+ */
+static inline int xfs_sb_has_mismatched_features2(xfs_sb_t *sbp)
+{
+ return (sbp->sb_bad_features2 != sbp->sb_features2);
+}
+
static inline unsigned xfs_sb_version_tonew(unsigned v)
{
return ((((v) == XFS_SB_VERSION_1) ? \