libblkid: set SBMAGIC for nilfs2

Reported-by: Mike Fleetwood <mike.fleetwood@googlemail.com>
Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/libblkid/src/superblocks/nilfs.c b/libblkid/src/superblocks/nilfs.c
index 3f03901260dbcbea3cdb147c6d87b3ebb55ccc6d..eccd8ae1db94b414dd6b89d25e018943eb8ed8e4 100644 (file)
--- a/libblkid/src/superblocks/nilfs.c
+++ b/libblkid/src/superblocks/nilfs.c
@@ -65,6 +65,7 @@ struct nilfs_super_block {
 
 #define NILFS_SB_MAGIC         0x3434
 #define NILFS_SB_OFFSET                0x400
+#define NILFS_SBB_OFFSET(_sz)  ((((_sz) / 0x200) - 8) * 0x200)
 
 static int nilfs_valid_sb(blkid_probe pr, struct nilfs_super_block *sb)
 {
@@ -88,15 +89,17 @@ static int probe_nilfs2(blkid_probe pr, const struct blkid_idmag *mag)
 {
        struct nilfs_super_block *sb, *sbp, *sbb;
        int valid[2], swp = 0;
+       uint64_t magoff;
 
        /* primary */
        sbp = (struct nilfs_super_block *) blkid_probe_get_buffer(
                        pr, NILFS_SB_OFFSET, sizeof(struct nilfs_super_block));
        if (!sbp)
                return errno ? -errno : 1;
+
        /* backup */
        sbb = (struct nilfs_super_block *) blkid_probe_get_buffer(
-                       pr, ((pr->size / 0x200) - 8) * 0x200, sizeof(struct nilfs_super_block));
+                       pr, NILFS_SBB_OFFSET(pr->size), sizeof(struct nilfs_super_block));
        if (!sbb)
                return errno ? -errno : 1;
 
@@ -124,6 +127,13 @@ static int probe_nilfs2(blkid_probe pr, const struct blkid_idmag *mag)
        blkid_probe_set_uuid(pr, sb->s_uuid);
        blkid_probe_sprintf_version(pr, "%u", le32_to_cpu(sb->s_rev_level));
 
+       magoff = swp ? NILFS_SBB_OFFSET(pr->size) : NILFS_SB_OFFSET;
+       magoff += offsetof(struct nilfs_super_block, s_magic);
+
+       if (blkid_probe_set_magic(pr, magoff, sizeof(sb->s_magic),
+                               (unsigned char *) &sb->s_magic))
+               return 1;
+
        return 0;
 }