[XFS] Fix superblock features2 field alignment problem

[linux-2.6-omap-h63xx.git] / fs / xfs / xfs_sb.h

diff --git a/fs/xfs/xfs_sb.h b/fs/xfs/xfs_sb.h
index d3a59735009ad0ed59d53ed0bd10fdb1a91f5201..b1a83f8ec04422b7aa6a4bc447754ca3af2dd6d3 100644 (file)
--- a/fs/xfs/xfs_sb.h
+++ b/fs/xfs/xfs_sb.h
@@ -89,6 +89,7 @@ struct xfs_mount;
 
 /*
  * 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 */
@@ -145,10 +146,21 @@ typedef struct xfs_sb {
        __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 */
@@ -205,6 +217,15 @@ typedef struct xfs_dsb {
        __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;
 
 /*
@@ -223,7 +244,7 @@ typedef enum {
        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;
 
@@ -248,13 +269,15 @@ typedef enum {
 #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)
 
 
 /*
@@ -296,6 +319,14 @@ static inline int xfs_sb_good_version(xfs_sb_t *sbp)
 }
 #endif /* __KERNEL__ */
 
+/*
+ * Detect a bad features2 field
+ */
+static inline int xfs_sb_has_bad_features2(xfs_sb_t *sbp)
+{
+       return (sbp->sb_bad_features2 != 0);
+}
+
 static inline unsigned xfs_sb_version_tonew(unsigned v)
 {
        return ((((v) == XFS_SB_VERSION_1) ? \