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-rw-r--r--libblkid/btrfs.c100
1 files changed, 100 insertions, 0 deletions
diff --git a/libblkid/btrfs.c b/libblkid/btrfs.c
new file mode 100644
index 000000000..5813035f3
--- /dev/null
+++ b/libblkid/btrfs.c
@@ -0,0 +1,100 @@
+/*
+ * Copyright (C) 2009 Karel Zak <kzak@redhat.com>
+ *
+ * This file may be redistributed under the terms of the
+ * GNU Lesser General Public License.
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdint.h>
+
+#include "superblocks.h"
+
+struct btrfs_super_block {
+ uint8_t csum[32];
+ uint8_t fsid[16];
+ uint64_t bytenr;
+ uint64_t flags;
+ uint8_t magic[8];
+ uint64_t generation;
+ uint64_t root;
+ uint64_t chunk_root;
+ uint64_t log_root;
+ uint64_t log_root_transid;
+ uint64_t total_bytes;
+ uint64_t bytes_used;
+ uint64_t root_dir_objectid;
+ uint64_t num_devices;
+ uint32_t sectorsize;
+ uint32_t nodesize;
+ uint32_t leafsize;
+ uint32_t stripesize;
+ uint32_t sys_chunk_array_size;
+ uint64_t chunk_root_generation;
+ uint64_t compat_flags;
+ uint64_t compat_ro_flags;
+ uint64_t incompat_flags;
+ uint16_t csum_type;
+ uint8_t root_level;
+ uint8_t chunk_root_level;
+ uint8_t log_root_level;
+ struct btrfs_dev_item {
+ uint64_t devid;
+ uint64_t total_bytes;
+ uint64_t bytes_used;
+ uint32_t io_align;
+ uint32_t io_width;
+ uint32_t sector_size;
+ uint64_t type;
+ uint64_t generation;
+ uint64_t start_offset;
+ uint32_t dev_group;
+ uint8_t seek_speed;
+ uint8_t bandwidth;
+ uint8_t uuid[16];
+ uint8_t fsid[16];
+ } __attribute__ ((__packed__)) dev_item;
+ uint8_t label[256];
+} __attribute__ ((__packed__));
+
+static int probe_btrfs(blkid_probe pr, const struct blkid_idmag *mag)
+{
+ struct btrfs_super_block *bfs;
+
+ if (mag->kboff > 64 && blkid_probe_ignore_backup(pr)) {
+ DBG(DEBUG_LOWPROBE, printf("btrfs: found backup superblock, ignore\n"));
+ return 1;
+ }
+
+ bfs = blkid_probe_get_sb(pr, mag, struct btrfs_super_block);
+ if (!bfs)
+ return -1;
+
+ if (*bfs->label)
+ blkid_probe_set_label(pr,
+ (unsigned char *) bfs->label,
+ sizeof(bfs->label));
+
+ blkid_probe_set_uuid(pr, bfs->fsid);
+ blkid_probe_set_uuid_as(pr, bfs->dev_item.uuid, "UUID_SUB");
+
+ return 0;
+}
+
+const struct blkid_idinfo btrfs_idinfo =
+{
+ .name = "btrfs",
+ .usage = BLKID_USAGE_FILESYSTEM,
+ .probefunc = probe_btrfs,
+ .minsz = 1024 * 1024,
+ .magics =
+ {
+ { .magic = "_BHRfS_M", .len = 8, .sboff = 0x40, .kboff = 64 },
+ { .magic = "_BHRfS_M", .len = 8, .sboff = 0x40, .kboff = 64 * 1024 },
+ { .magic = "_BHRfS_M", .len = 8, .sboff = 0x40, .kboff = 256 * 1024 * 1024 },
+ { NULL }
+ }
+};
+