Merge tag 'perf-urgent-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git...

[cascardo/linux.git] / fs / xfs / libxfs / xfs_format.h

diff --git a/fs/xfs/libxfs/xfs_format.h b/fs/xfs/libxfs/xfs_format.h
index a0ae572..9590a06 100644 (file)
--- a/fs/xfs/libxfs/xfs_format.h
+++ b/fs/xfs/libxfs/xfs_format.h
@@ -100,7 +100,7 @@ typedef struct xfs_sb {
        xfs_rfsblock_t  sb_dblocks;     /* number of data blocks */
        xfs_rfsblock_t  sb_rblocks;     /* number of realtime blocks */
        xfs_rtblock_t   sb_rextents;    /* number of realtime extents */
-       uuid_t          sb_uuid;        /* file system unique id */
+       uuid_t          sb_uuid;        /* user-visible file system unique id */
        xfs_fsblock_t   sb_logstart;    /* starting block of log if internal */
        xfs_ino_t       sb_rootino;     /* root inode number */
        xfs_ino_t       sb_rbmino;      /* bitmap inode for realtime extents */
@@ -174,6 +174,7 @@ typedef struct xfs_sb {
 
        xfs_ino_t       sb_pquotino;    /* project quota inode */
        xfs_lsn_t       sb_lsn;         /* last write sequence */
+       uuid_t          sb_meta_uuid;   /* metadata file system unique id */
 
        /* must be padded to 64 bit alignment */
 } xfs_sb_t;
@@ -190,7 +191,7 @@ typedef struct xfs_dsb {
        __be64          sb_dblocks;     /* number of data blocks */
        __be64          sb_rblocks;     /* number of realtime blocks */
        __be64          sb_rextents;    /* number of realtime extents */
-       uuid_t          sb_uuid;        /* file system unique id */
+       uuid_t          sb_uuid;        /* user-visible file system unique id */
        __be64          sb_logstart;    /* starting block of log if internal */
        __be64          sb_rootino;     /* root inode number */
        __be64          sb_rbmino;      /* bitmap inode for realtime extents */
@@ -260,6 +261,7 @@ typedef struct xfs_dsb {
 
        __be64          sb_pquotino;    /* project quota inode */
        __be64          sb_lsn;         /* last write sequence */
+       uuid_t          sb_meta_uuid;   /* metadata file system unique id */
 
        /* must be padded to 64 bit alignment */
 } xfs_dsb_t;
@@ -458,9 +460,11 @@ xfs_sb_has_ro_compat_feature(
 
 #define XFS_SB_FEAT_INCOMPAT_FTYPE     (1 << 0)        /* filetype in dirent */
 #define XFS_SB_FEAT_INCOMPAT_SPINODES  (1 << 1)        /* sparse inode chunks */
+#define XFS_SB_FEAT_INCOMPAT_META_UUID (1 << 2)        /* metadata UUID */
 #define XFS_SB_FEAT_INCOMPAT_ALL \
                (XFS_SB_FEAT_INCOMPAT_FTYPE|    \
-                XFS_SB_FEAT_INCOMPAT_SPINODES)
+                XFS_SB_FEAT_INCOMPAT_SPINODES| \
+                XFS_SB_FEAT_INCOMPAT_META_UUID)
 
 #define XFS_SB_FEAT_INCOMPAT_UNKNOWN   ~XFS_SB_FEAT_INCOMPAT_ALL
 static inline bool
@@ -514,6 +518,18 @@ static inline bool xfs_sb_version_hassparseinodes(struct xfs_sb *sbp)
                xfs_sb_has_incompat_feature(sbp, XFS_SB_FEAT_INCOMPAT_SPINODES);
 }
 
+/*
+ * XFS_SB_FEAT_INCOMPAT_META_UUID indicates that the metadata UUID
+ * is stored separately from the user-visible UUID; this allows the
+ * user-visible UUID to be changed on V5 filesystems which have a
+ * filesystem UUID stamped into every piece of metadata.
+ */
+static inline bool xfs_sb_version_hasmetauuid(struct xfs_sb *sbp)
+{
+       return (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5) &&
+               (sbp->sb_features_incompat & XFS_SB_FEAT_INCOMPAT_META_UUID);
+}
+
 /*
  * end of superblock version macros
  */