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Diffstat (limited to 'libblkid/src/superblocks/drbd.c')
| -rw-r--r-- | libblkid/src/superblocks/drbd.c | 231 |
1 files changed, 231 insertions, 0 deletions
diff --git a/libblkid/src/superblocks/drbd.c b/libblkid/src/superblocks/drbd.c new file mode 100644 index 0000000..f360186 --- /dev/null +++ b/libblkid/src/superblocks/drbd.c @@ -0,0 +1,231 @@ +/* + * Copyright (C) 2009 by Bastian Friedrich <bastian.friedrich@collax.com> + * + * This file may be redistributed under the terms of the + * GNU Lesser General Public License. + * + * defines, structs taken from drbd source; file names represent drbd source + * files. + */ +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <string.h> +#include <errno.h> +#include <ctype.h> +#include <inttypes.h> +#include <stddef.h> + +#include "superblocks.h" + +/* + * drbd/linux/drbd.h + */ +#define DRBD_MAGIC 0x83740267 + +/* + * user/drbdmeta.c + * 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 + */ +enum drbd_uuid_index { + UI_CURRENT, + UI_BITMAP, + UI_HISTORY_START, + UI_HISTORY_END, + UI_SIZE, /* nl-packet: number of dirty bits */ + UI_FLAGS, /* nl-packet: flags */ + UI_EXTENDED_SIZE /* Everything. */ +}; + + +/* + * Used by libblkid to avoid unnecessary padding at the end of the structs and + * too large unused structs in memory. + */ +#define DRBD_MD_OFFSET 4096 + +/* + * user/shared/drbdmeta.c + * Minor modifications wrt. types + */ +struct md_on_disk_08 { + uint64_t la_sect; /* last agreed size. */ + uint64_t uuid[UI_SIZE]; /* UUIDs */ + uint64_t device_uuid; + uint64_t reserved_u64_1; + uint32_t flags; + uint32_t magic; + uint32_t md_size_sect; + int32_t al_offset; /* signed sector offset to this block */ + uint32_t al_nr_extents; /* important for restoring the AL */ + int32_t bm_offset; /* signed sector offset to the bitmap, from here */ + uint32_t bm_bytes_per_bit; + uint32_t reserved_u32[4]; + + /* Unnecessary for libblkid ** + * 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 + +/* + * 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]; + + /* Unnecessary for libblkid ** + * 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; + + off = pr->size - DRBD_MD_OFFSET; + + /* Small devices cannot be drbd (?) */ + if (pr->size < 0x10000) + return 1; + + md = (struct md_on_disk_08 *) + blkid_probe_get_buffer(pr, + off, + sizeof(struct md_on_disk_08)); + if (!md) + return errno ? -errno : 1; + + if (be32_to_cpu(md->magic) != DRBD_MD_MAGIC_08 && + be32_to_cpu(md->magic) != DRBD_MD_MAGIC_84_UNCLEAN) + 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, "v08"); + + if (blkid_probe_set_magic(pr, + off + offsetof(struct md_on_disk_08, magic), + sizeof(md->magic), + (unsigned char *) &md->magic)) + return 1; + + return 0; +} + +static int probe_drbd_90(blkid_probe pr) +{ + struct meta_data_on_disk_9 *md; + off_t off; + + off = pr->size - DRBD_MD_OFFSET; + + /* + * 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", + .usage = BLKID_USAGE_RAID, + .probefunc = probe_drbd, + .magics = BLKID_NONE_MAGIC +}; + |