libblkid: add check for DRBD9

This adds the according meta-data structs + defines and an additional
function to detect DRBD9 magics.

Signed-off-by: Roland Kammerer <roland.kammerer@linbit.com>

diff --git a/libblkid/src/superblocks/drbd.c b/libblkid/src/superblocks/drbd.c
index e88e9f353a411da5df16a8b567360b521827702f..4ebaf1739932aae7352f880db9f5080ef2500e76 100644 (file)
--- a/libblkid/src/superblocks/drbd.c
+++ b/libblkid/src/superblocks/drbd.c
@@ -25,10 +25,12 @@
 
 /*
  * user/drbdmeta.c
- * We only support v08 for now
+ * We support v08 and v09
  */
 #define DRBD_MD_MAGIC_08         (DRBD_MAGIC+4)
 #define DRBD_MD_MAGIC_84_UNCLEAN (DRBD_MAGIC+5)
+#define DRBD_MD_MAGIC_09         (DRBD_MAGIC+6)
+/* there is no DRBD_MD_MAGIC_09_UNCLEAN */
 
 /*
  * drbd/linux/drbd.h
@@ -44,7 +46,7 @@ enum drbd_uuid_index {
 };
 
 /*
- * user/drbdmeta.c
+ * user/shared/drbdmeta.c
  * Minor modifications wrt. types
  */
 struct md_on_disk_08 {
@@ -64,9 +66,54 @@ struct md_on_disk_08 {
        char reserved[8 * 512 - (8*(UI_SIZE+3)+4*11)];
 };
 
+/*
+ * linux/drbd.h, v9 only
+ */
+#define DRBD_PEERS_MAX 32
+#define HISTORY_UUIDS DRBD_PEERS_MAX
 
-static int probe_drbd(blkid_probe pr,
-               const struct blkid_idmag *mag __attribute__((__unused__)))
+/*
+ * drbd-headers/drbd_meta_data.h
+ * Minor modifications wrt. types
+ */
+struct peer_dev_md_on_disk_9 {
+       uint64_t bitmap_uuid;
+       uint64_t bitmap_dagtag;
+       uint32_t flags;
+       int32_t bitmap_index;
+       uint32_t reserved_u32[2];
+} __attribute__((packed));
+
+struct meta_data_on_disk_9 {
+       uint64_t effective_size;    /* last agreed size */
+       uint64_t current_uuid;
+       uint64_t reserved_u64[4];   /* to have the magic at the same position as in v07, and v08 */
+       uint64_t device_uuid;
+       uint32_t flags;             /* MDF */
+       uint32_t magic;
+       uint32_t md_size_sect;
+       uint32_t al_offset;         /* offset to this block */
+       uint32_t al_nr_extents;     /* important for restoring the AL */
+       uint32_t bm_offset;         /* offset to the bitmap, from here */
+       uint32_t bm_bytes_per_bit;  /* BM_BLOCK_SIZE */
+       uint32_t la_peer_max_bio_size;   /* last peer max_bio_size */
+       uint32_t bm_max_peers;
+       int32_t node_id;
+
+       /* see al_tr_number_to_on_disk_sector() */
+       uint32_t al_stripes;
+       uint32_t al_stripe_size_4k;
+
+       uint32_t reserved_u32[2];
+
+       struct peer_dev_md_on_disk_9 peers[DRBD_PEERS_MAX];
+       uint64_t history_uuids[HISTORY_UUIDS];
+
+       char padding[0] __attribute__((aligned(4096)));
+} __attribute__((packed));
+
+
+static int probe_drbd_84(blkid_probe pr)
 {
        struct md_on_disk_08 *md;
        off_t off;
@@ -107,6 +154,62 @@ static int probe_drbd(blkid_probe pr,
        return 0;
 }
 
+static int probe_drbd_90(blkid_probe pr)
+{
+       struct meta_data_on_disk_9 *md;
+       off_t off;
+
+       off = pr->size - sizeof(*md);
+
+       /*
+        * Smaller ones are certainly not DRBD9 devices.
+        * Recent utils even refuse to generate larger ones,
+        * keep this as a sufficient lower bound.
+        */
+       if (pr->size < 0x10000)
+               return 1;
+
+       md = (struct meta_data_on_disk_9 *)
+                       blkid_probe_get_buffer(pr,
+                                       off,
+                                       sizeof(struct meta_data_on_disk_9));
+       if (!md)
+               return errno ? -errno : 1;
+
+       if (be32_to_cpu(md->magic) != DRBD_MD_MAGIC_09)
+               return 1;
+
+       /*
+        * DRBD does not have "real" uuids; the following resembles DRBD's
+        * notion of uuids (64 bit, see struct above)
+        */
+       blkid_probe_sprintf_uuid(pr,
+               (unsigned char *) &md->device_uuid, sizeof(md->device_uuid),
+               "%" PRIx64, be64_to_cpu(md->device_uuid));
+
+       blkid_probe_set_version(pr, "v09");
+
+       if (blkid_probe_set_magic(pr,
+                               off + offsetof(struct meta_data_on_disk_9, magic),
+                               sizeof(md->magic),
+                               (unsigned char *) &md->magic))
+               return 1;
+
+       return 0;
+}
+
+static int probe_drbd(blkid_probe pr,
+               const struct blkid_idmag *mag __attribute__((__unused__)))
+{
+       int ret;
+
+       ret = probe_drbd_84(pr);
+       if (ret <= 0) /* success or fatal (-errno) */
+               return ret;
+
+       return probe_drbd_90(pr);
+}
+
 const struct blkid_idinfo drbd_idinfo =
 {
        .name           = "drbd",