Add ZFS detection to libblkid

This patch adds ZFS filesystem detection to libblkid.

It probes for VDEV_BOOT_MAGIC in the first 2 ZFS labels in big-endian
and little-endian formats.
Unfortunately the probe table doesn't support probing from the end of
the device, otherwise we could also probe in the 3rd and 4th labels (in
case the first 2 labels were accidentally overwritten)..

Eventually we would set the UUID from the ZFS pool GUID and the LABEL tag
from the pool name, but that requires parsing an XDR encoding of the pool
configuration which is not trivial.

Signed-off-by: Ricardo M. Correia <Ricardo.M.Correia@Sun.COM>
Signed-off-by: Andreas Dilger <adilger@sun.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/lib/blkid/probe.c b/lib/blkid/probe.c
index 62ab392dc88328cc6880a0e4c0943f9db478e042..f548d08e02e3e7d3c96d1fc522987007d1b18808 100644 (file)
--- a/lib/blkid/probe.c
+++ b/lib/blkid/probe.c
@@ -774,6 +774,20 @@ static int probe_jfs(struct blkid_probe *probe,
        return 0;
 }
 
+static int probe_zfs(struct blkid_probe *probe, struct blkid_magic *id,
+                    unsigned char *buf)
+{
+       char *vdev_label;
+       const char *pool_name = 0;
+
+       /* read nvpair data for pool name, pool GUID (complex) */
+#if 0
+       blkid_set_tag(probe->dev, "LABEL", pool_name, sizeof(pool_name));
+       set_uuid(probe->dev, pool_guid, 0);
+#endif
+       return 0;
+}
+
 static int probe_luks(struct blkid_probe *probe,
                       struct blkid_magic *id __BLKID_ATTR((unused)),
                       unsigned char *buf)
@@ -1088,15 +1102,6 @@ static int probe_lvm2(struct blkid_probe *probe,
 
        return 0;
 }
-/*
- * BLKID_BLK_OFFS is at least as large as the highest bim_kboff defined
- * in the type_array table below + bim_kbalign.
- *
- * When probing for a lot of magics, we handle everything in 1kB buffers so
- * that we don't have to worry about reading each combination of block sizes.
- */
-#define BLKID_BLK_OFFS 64      /* currently reiserfs */
-
 /*
  * Various filesystem magics that we can check for.  Note that kboff and
  * sboff are in kilobytes and bytes respectively.  All magics are in
@@ -1147,6 +1152,10 @@ static struct blkid_magic type_array[] = {
   { "iso9660", 32,      1,  5, "CD001",                probe_iso9660 },
   { "iso9660", 32,      9,  5, "CDROM",                probe_iso9660 },
   { "jfs",     32,      0,  4, "JFS1",                 probe_jfs },
+  { "zfs",       8,     0,  8, "\0\0\x02\xf5\xb0\x07\xb1\x0c", probe_zfs },
+  { "zfs",       8,     0,  8, "\x0c\xb1\x07\xb0\xf5\x02\0\0", probe_zfs },
+  { "zfs",     264,     0,  8, "\0\0\x02\xf5\xb0\x07\xb1\x0c", probe_zfs },
+  { "zfs",     264,     0,  8, "\x0c\xb1\x07\xb0\xf5\x02\0\0", probe_zfs },
   { "hfsplus",  1,      0,  2, "BD",                   probe_hfsplus },
   { "hfsplus",  1,      0,  2, "H+",                   0 },
   { "hfs",      1,      0,  2, "BD",                   0 },
@@ -1282,7 +1291,7 @@ try_again:
                if (!buf)
                        continue;
 
-               if (memcmp(id->bim_magic, buf + (id->bim_sboff&0x3ff),
+               if (memcmp(id->bim_magic, buf + (id->bim_sboff & 0x3ff),
                           id->bim_len))
                        continue;
 
@@ -1312,7 +1321,7 @@ try_again:
                dev = 0;
                goto found_type;
        }
-               
+
 found_type:
        if (dev && type) {
                dev->bid_devno = st.st_rdev;
@@ -1321,7 +1330,7 @@ found_type:
                cache->bic_flags |= BLKID_BIC_FL_CHANGED;
 
                blkid_set_tag(dev, "TYPE", type, 0);
-                               
+
                DBG(DEBUG_PROBE, printf("%s: devno 0x%04llx, type %s\n",
                           dev->bid_name, (long long)st.st_rdev, type));
        }