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-rw-r--r--libblkid/linux_raid.c258
1 files changed, 258 insertions, 0 deletions
diff --git a/libblkid/linux_raid.c b/libblkid/linux_raid.c
new file mode 100644
index 000000000..a3f9d67d5
--- /dev/null
+++ b/libblkid/linux_raid.c
@@ -0,0 +1,258 @@
+/*
+ * Copyright (C) 2008 Karel Zak <kzak@redhat.com>
+ *
+ * Inspired by libvolume_id by
+ * Kay Sievers <kay.sievers@vrfy.org>
+ *
+ * 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 mdp0_super_block {
+ uint32_t md_magic;
+ uint32_t major_version;
+ uint32_t minor_version;
+ uint32_t patch_version;
+ uint32_t gvalid_words;
+ uint32_t set_uuid0;
+ uint32_t ctime;
+ uint32_t level;
+ uint32_t size;
+ uint32_t nr_disks;
+ uint32_t raid_disks;
+ uint32_t md_minor;
+ uint32_t not_persistent;
+ uint32_t set_uuid1;
+ uint32_t set_uuid2;
+ uint32_t set_uuid3;
+};
+
+/*
+ * Version-1, little-endian.
+ */
+struct mdp1_super_block {
+ /* constant array information - 128 bytes */
+ uint32_t magic; /* MD_SB_MAGIC: 0xa92b4efc - little endian */
+ uint32_t major_version; /* 1 */
+ uint32_t feature_map; /* 0 for now */
+ uint32_t pad0; /* always set to 0 when writing */
+
+ uint8_t set_uuid[16]; /* user-space generated. */
+ unsigned char set_name[32]; /* set and interpreted by user-space */
+
+ uint64_t ctime; /* lo 40 bits are seconds, top 24 are microseconds or 0*/
+ uint32_t level; /* -4 (multipath), -1 (linear), 0,1,4,5 */
+ uint32_t layout; /* only for raid5 currently */
+ uint64_t size; /* used size of component devices, in 512byte sectors */
+
+ uint32_t chunksize; /* in 512byte sectors */
+ uint32_t raid_disks;
+ uint32_t bitmap_offset; /* sectors after start of superblock that bitmap starts
+ * NOTE: signed, so bitmap can be before superblock
+ * only meaningful of feature_map[0] is set.
+ */
+
+ /* These are only valid with feature bit '4' */
+ uint32_t new_level; /* new level we are reshaping to */
+ uint64_t reshape_position; /* next address in array-space for reshape */
+ uint32_t delta_disks; /* change in number of raid_disks */
+ uint32_t new_layout; /* new layout */
+ uint32_t new_chunk; /* new chunk size (bytes) */
+ uint8_t pad1[128-124]; /* set to 0 when written */
+
+ /* constant this-device information - 64 bytes */
+ uint64_t data_offset; /* sector start of data, often 0 */
+ uint64_t data_size; /* sectors in this device that can be used for data */
+ uint64_t super_offset; /* sector start of this superblock */
+ uint64_t recovery_offset;/* sectors before this offset (from data_offset) have been recovered */
+ uint32_t dev_number; /* permanent identifier of this device - not role in raid */
+ uint32_t cnt_corrected_read; /* number of read errors that were corrected by re-writing */
+ uint8_t device_uuid[16]; /* user-space setable, ignored by kernel */
+ uint8_t devflags; /* per-device flags. Only one defined...*/
+ uint8_t pad2[64-57]; /* set to 0 when writing */
+
+ /* array state information - 64 bytes */
+ uint64_t utime; /* 40 bits second, 24 btes microseconds */
+ uint64_t events; /* incremented when superblock updated */
+ uint64_t resync_offset; /* data before this offset (from data_offset) known to be in sync */
+ uint32_t sb_csum; /* checksum up to dev_roles[max_dev] */
+ uint32_t max_dev; /* size of dev_roles[] array to consider */
+ uint8_t pad3[64-32]; /* set to 0 when writing */
+
+ /* device state information. Indexed by dev_number.
+ * 2 bytes per device
+ * Note there are no per-device state flags. State information is rolled
+ * into the 'roles' value. If a device is spare or faulty, then it doesn't
+ * have a meaningful role.
+ */
+ uint16_t dev_roles[0]; /* role in array, or 0xffff for a spare, or 0xfffe for faulty */
+};
+
+
+#define MD_RESERVED_BYTES 0x10000
+#define MD_SB_MAGIC 0xa92b4efc
+
+static int probe_raid0(blkid_probe pr, blkid_loff_t off)
+{
+ struct mdp0_super_block *mdp0;
+ union {
+ uint32_t ints[4];
+ uint8_t bytes[16];
+ } uuid;
+ uint32_t ma, mi, pa;
+ uint64_t size;
+
+ if (pr->size < MD_RESERVED_BYTES)
+ return -1;
+ mdp0 = (struct mdp0_super_block *)
+ blkid_probe_get_buffer(pr,
+ off,
+ sizeof(struct mdp0_super_block));
+ if (!mdp0)
+ return -1;
+
+ memset(uuid.ints, 0, sizeof(uuid.ints));
+
+ if (le32_to_cpu(mdp0->md_magic) == MD_SB_MAGIC) {
+ uuid.ints[0] = swab32(mdp0->set_uuid0);
+ if (le32_to_cpu(mdp0->minor_version) >= 90) {
+ uuid.ints[1] = swab32(mdp0->set_uuid1);
+ uuid.ints[2] = swab32(mdp0->set_uuid2);
+ uuid.ints[3] = swab32(mdp0->set_uuid3);
+ }
+ ma = le32_to_cpu(mdp0->major_version);
+ mi = le32_to_cpu(mdp0->minor_version);
+ pa = le32_to_cpu(mdp0->patch_version);
+ size = le32_to_cpu(mdp0->size);
+
+ } else if (be32_to_cpu(mdp0->md_magic) == MD_SB_MAGIC) {
+ uuid.ints[0] = mdp0->set_uuid0;
+ if (be32_to_cpu(mdp0->minor_version) >= 90) {
+ uuid.ints[1] = mdp0->set_uuid1;
+ uuid.ints[2] = mdp0->set_uuid2;
+ uuid.ints[3] = mdp0->set_uuid3;
+ }
+ ma = be32_to_cpu(mdp0->major_version);
+ mi = be32_to_cpu(mdp0->minor_version);
+ pa = be32_to_cpu(mdp0->patch_version);
+ size = be32_to_cpu(mdp0->size);
+ } else
+ return 1;
+
+ size <<= 10; /* convert KiB to bytes */
+
+ if (pr->size < 0 || (uint64_t) pr->size < size + MD_RESERVED_BYTES)
+ /* device is too small */
+ return 1;
+
+ if (off < 0 || (uint64_t) off < size)
+ /* no space before superblock */
+ return 1;
+
+ /*
+ * Check for collisions between RAID and partition table
+ *
+ * For example the superblock is at the end of the last partition, it's
+ * the same position as at the end of the disk...
+ */
+ if ((S_ISREG(pr->mode) || blkid_probe_is_wholedisk(pr)) &&
+ blkid_probe_is_covered_by_pt(pr,
+ off - size, /* min. start */
+ size + MD_RESERVED_BYTES)) { /* min. length */
+
+ /* ignore this superblock, it's within any partition and
+ * we are working with whole-disk now */
+ return 1;
+ }
+
+ if (blkid_probe_sprintf_version(pr, "%u.%u.%u", ma, mi, pa) != 0)
+ return -1;
+ if (blkid_probe_set_uuid(pr, (unsigned char *) uuid.bytes) != 0)
+ return -1;
+ if (blkid_probe_set_magic(pr, off, sizeof(mdp0->md_magic),
+ (unsigned char *) &mdp0->md_magic))
+ return -1;
+ return 0;
+}
+
+static int probe_raid1(blkid_probe pr, off_t off)
+{
+ struct mdp1_super_block *mdp1;
+
+ mdp1 = (struct mdp1_super_block *)
+ blkid_probe_get_buffer(pr,
+ off,
+ sizeof(struct mdp1_super_block));
+ if (!mdp1)
+ return -1;
+ if (le32_to_cpu(mdp1->magic) != MD_SB_MAGIC)
+ return -1;
+ if (le32_to_cpu(mdp1->major_version) != 1U)
+ return -1;
+ if (le64_to_cpu(mdp1->super_offset) != (uint64_t) off >> 9)
+ return -1;
+ if (blkid_probe_set_uuid(pr, (unsigned char *) mdp1->set_uuid) != 0)
+ return -1;
+ if (blkid_probe_set_uuid_as(pr,
+ (unsigned char *) mdp1->device_uuid, "UUID_SUB") != 0)
+ return -1;
+ if (blkid_probe_set_label(pr, mdp1->set_name,
+ sizeof(mdp1->set_name)) != 0)
+ return -1;
+ if (blkid_probe_set_magic(pr, off, sizeof(mdp1->magic),
+ (unsigned char *) &mdp1->magic))
+ return -1;
+ return 0;
+}
+
+int probe_raid(blkid_probe pr,
+ const struct blkid_idmag *mag __attribute__((__unused__)))
+{
+ const char *ver = NULL;
+
+ if (pr->size > MD_RESERVED_BYTES) {
+ /* version 0 at the end of the device */
+ uint64_t sboff = (pr->size & ~(MD_RESERVED_BYTES - 1))
+ - MD_RESERVED_BYTES;
+ if (probe_raid0(pr, sboff) == 0)
+ return 0;
+
+ /* version 1.0 at the end of the device */
+ sboff = (pr->size & ~(0x1000 - 1)) - 0x2000;
+ if (probe_raid1(pr, sboff) == 0)
+ ver = "1.0";
+ }
+
+ if (!ver) {
+ /* version 1.1 at the start of the device */
+ if (probe_raid1(pr, 0) == 0)
+ ver = "1.1";
+
+ /* version 1.2 at 4k offset from the start */
+ else if (probe_raid1(pr, 0x1000) == 0)
+ ver = "1.2";
+ }
+
+ if (ver) {
+ blkid_probe_set_version(pr, ver);
+ return 0;
+ }
+ return -1;
+}
+
+
+const struct blkid_idinfo linuxraid_idinfo = {
+ .name = "linux_raid_member",
+ .usage = BLKID_USAGE_RAID,
+ .probefunc = probe_raid,
+ .magics = BLKID_NONE_MAGIC
+};
+
+