libblkid: fix ZSF detection

Fix the ZFS device detection by looking at multiple uberblocks to see
if any are present, rather than looking for the ZFS boot block which
is not always present.

There may be up to 128 uberblocks, but the first 4 are not written to
disk on a newly-formatted filesystem so check several of them at
different offsets within the uberblock array.

[kzak@redhat.com: - port e2fsprogs patch to util-linux-ng]

Signed-off-by: Andreas Dilger <adilger@sun.com>
Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/shlibs/blkid/src/superblocks/zfs.c b/shlibs/blkid/src/superblocks/zfs.c
index 0f580262218f1fa40b358245409b0f27d4a6061b..3ee9369650edfd4c00934cadb257d5f4409fb48b 100644 (file)
--- a/shlibs/blkid/src/superblocks/zfs.c
+++ b/shlibs/blkid/src/superblocks/zfs.c
@@ -23,21 +23,22 @@ struct zfs_uberblock {
        uint64_t        ub_txg;         /* txg of last sync             */
        uint64_t        ub_guid_sum;    /* sum of all vdev guids        */
        uint64_t        ub_timestamp;   /* UTC time of last sync        */
-       /*blkptr_t      ub_rootbp;*/    /* MOS objset_phys_t            */
+       char            ub_rootbp;      /* MOS objset_phys_t            */
 } __attribute__((packed));
 
 static int probe_zfs(blkid_probe pr, const struct blkid_idmag *mag)
 {
        struct zfs_uberblock *ub;
-       int swab_endian;
        uint64_t spa_version;
 
        ub = blkid_probe_get_sb(pr, mag, struct zfs_uberblock);
        if (!ub)
                return -1;
 
-       swab_endian = (ub->ub_magic == swab64(UBERBLOCK_MAGIC));
-       spa_version = swab_endian ? swab64(ub->ub_version) : ub->ub_version;
+       if (ub->ub_magic == be64_to_cpu(UBERBLOCK_MAGIC))
+               spa_version = be64_to_cpu(ub->ub_version);
+       else
+               spa_version = le64_to_cpu(ub->ub_version);
 
        blkid_probe_sprintf_version(pr, "%" PRIu64, spa_version);
 #if 0
@@ -57,10 +58,19 @@ const struct blkid_idinfo zfs_idinfo =
        .minsz          = 64 * 1024 * 1024,
        .magics         =
        {
-               { .magic = "\0\0\x02\xf5\xb0\x07\xb1\x0c", .len = 8, .kboff = 8 },
-               { .magic = "\x1c\xb1\x07\xb0\xf5\x02\0\0", .len = 8, .kboff = 8 },
-               { .magic = "\0\0\x02\xf5\xb0\x07\xb1\x0c", .len = 8, .kboff = 264 },
-               { .magic = "\x0c\xb1\x07\xb0\xf5\x02\0\0", .len = 8, .kboff = 264 },
+               /* ZFS has 128 root blocks (#4 is the first used), check only 6 of them */
+               { .magic = "\0\0\0\0\0\xba\xb1\x0c", .len = 8, .kboff = 128 },
+               { .magic = "\x0c\xb1\xba\0\0\0\0\0", .len = 8, .kboff = 128 },
+               { .magic = "\0\0\0\0\0\xba\xb1\x0c", .len = 8, .kboff = 132 },
+               { .magic = "\x0c\xb1\xba\0\0\0\0\0", .len = 8, .kboff = 132 },
+               { .magic = "\0\0\0\0\0\xba\xb1\x0c", .len = 8, .kboff = 136 },
+               { .magic = "\x0c\xb1\xba\0\0\0\0\0", .len = 8, .kboff = 136 },
+               { .magic = "\0\0\0\0\0\xba\xb1\x0c", .len = 8, .kboff = 384 },
+               { .magic = "\x0c\xb1\xba\0\0\0\0\0", .len = 8, .kboff = 384 },
+               { .magic = "\0\0\0\0\0\xba\xb1\x0c", .len = 8, .kboff = 388 },
+               { .magic = "\x0c\xb1\xba\0\0\0\0\0", .len = 8, .kboff = 388 },
+               { .magic = "\0\0\0\0\0\xba\xb1\x0c", .len = 8, .kboff = 392 },
+               { .magic = "\x0c\xb1\xba\0\0\0\0\0", .len = 8, .kboff = 392 },
                { NULL }
        }
 };

diff --git a/tests/expected/blkid/low-probe-zfs b/tests/expected/blkid/low-probe-zfs
index 94cec8b3caa37c14289b9637116fd616f905d6ec..8159f18c129dffdf70922f51a846fdd19da0d980 100644 (file)
--- a/tests/expected/blkid/low-probe-zfs
+++ b/tests/expected/blkid/low-probe-zfs
@@ -1,3 +1,3 @@
 ID_FS_TYPE=zfs
 ID_FS_USAGE=filesystem
-ID_FS_VERSION=1
+ID_FS_VERSION=8