diff options
Diffstat (limited to 'libblkid/src/superblocks/nilfs.c')
| -rw-r--r-- | libblkid/src/superblocks/nilfs.c | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/libblkid/src/superblocks/nilfs.c b/libblkid/src/superblocks/nilfs.c new file mode 100644 index 0000000..95538ef --- /dev/null +++ b/libblkid/src/superblocks/nilfs.c @@ -0,0 +1,171 @@ +/* + * Copyright (C) 2010 by Jiro SEKIBA <jir@unicus.jp> + * + * This file may be redistributed under the terms of the + * GNU Lesser General Public License + */ +#include <stddef.h> +#include <string.h> + +#include "superblocks.h" +#include "crc32.h" + +struct nilfs_super_block { + uint32_t s_rev_level; + uint16_t s_minor_rev_level; + uint16_t s_magic; + + uint16_t s_bytes; + + uint16_t s_flags; + uint32_t s_crc_seed; + uint32_t s_sum; + + uint32_t s_log_block_size; + + uint64_t s_nsegments; + uint64_t s_dev_size; + uint64_t s_first_data_block; + uint32_t s_blocks_per_segment; + uint32_t s_r_segments_percentage; + + uint64_t s_last_cno; + uint64_t s_last_pseg; + uint64_t s_last_seq; + uint64_t s_free_blocks_count; + + uint64_t s_ctime; + + uint64_t s_mtime; + uint64_t s_wtime; + uint16_t s_mnt_count; + uint16_t s_max_mnt_count; + uint16_t s_state; + uint16_t s_errors; + uint64_t s_lastcheck; + + uint32_t s_checkinterval; + uint32_t s_creator_os; + uint16_t s_def_resuid; + uint16_t s_def_resgid; + uint32_t s_first_ino; + + uint16_t s_inode_size; + uint16_t s_dat_entry_size; + uint16_t s_checkpoint_size; + uint16_t s_segment_usage_size; + + uint8_t s_uuid[16]; + char s_volume_name[80]; + + uint32_t s_c_interval; + uint32_t s_c_block_max; + uint32_t s_reserved[192]; +}; + +#define NILFS_SB_MAGIC 0x3434 +#define NILFS_SB_OFFSET 0x400 +#define NILFS_SBB_OFFSET(_sz) ((((_sz) / 0x200) - 8) * 0x200) + +static int nilfs_valid_sb(blkid_probe pr, struct nilfs_super_block *sb, int is_bak) +{ + static unsigned char sum[4]; + const int sumoff = offsetof(struct nilfs_super_block, s_sum); + size_t bytes; + const size_t crc_start = sumoff + 4; + uint32_t crc; + + if (!sb || le16_to_cpu(sb->s_magic) != NILFS_SB_MAGIC) + return 0; + + if (is_bak && blkid_probe_is_wholedisk(pr) && + sb->s_dev_size != pr->size) + return 0; + + bytes = le16_to_cpu(sb->s_bytes); + /* ensure that no underrun can happen in the length parameter + * of the crc32 call or more data are processed than read into + * sb */ + if (bytes < crc_start || bytes > sizeof(struct nilfs_super_block)) + return 0; + + crc = ul_crc32(le32_to_cpu(sb->s_crc_seed), (unsigned char *)sb, sumoff); + crc = ul_crc32(crc, sum, 4); + crc = ul_crc32(crc, (unsigned char *)sb + crc_start, bytes - crc_start); + + return blkid_probe_verify_csum(pr, crc, le32_to_cpu(sb->s_sum)); +} + +static int probe_nilfs2(blkid_probe pr, + const struct blkid_idmag *mag __attribute__((__unused__))) +{ + struct nilfs_super_block *sb, *sbp, *sbb; + int valid[2], swp = 0; + uint64_t magoff; + + /* primary */ + sbp = (struct nilfs_super_block *) blkid_probe_get_buffer( + pr, NILFS_SB_OFFSET, sizeof(struct nilfs_super_block)); + if (!sbp) + return errno ? -errno : 1; + + valid[0] = nilfs_valid_sb(pr, sbp, 0); + + + /* backup */ + sbb = (struct nilfs_super_block *) blkid_probe_get_buffer( + pr, NILFS_SBB_OFFSET(pr->size), sizeof(struct nilfs_super_block)); + if (!sbb) { + valid[1] = 0; + + /* If the primary block is valid then continue and ignore also + * I/O errors for backup block. Note the this is probably CD + * where I/O errors and the end of the disk/session are "normal". + */ + if (!valid[0]) + return errno ? -errno : 1; + } else + valid[1] = nilfs_valid_sb(pr, sbb, 1); + + + /* + * Compare two super blocks and set 1 in swp if the secondary + * super block is valid and newer. Otherwise, set 0 in swp. + */ + if (!valid[0] && !valid[1]) + return 1; + + swp = valid[1] && (!valid[0] || + le64_to_cpu(sbp->s_last_cno) > + le64_to_cpu(sbb->s_last_cno)); + sb = swp ? sbb : sbp; + + DBG(LOWPROBE, ul_debug("nilfs2: primary=%d, backup=%d, swap=%d", + valid[0], valid[1], swp)); + + if (*(sb->s_volume_name) != '\0') + blkid_probe_set_label(pr, (unsigned char *) sb->s_volume_name, + sizeof(sb->s_volume_name)); + + blkid_probe_set_uuid(pr, sb->s_uuid); + blkid_probe_sprintf_version(pr, "%u", le32_to_cpu(sb->s_rev_level)); + + magoff = swp ? NILFS_SBB_OFFSET(pr->size) : NILFS_SB_OFFSET; + magoff += offsetof(struct nilfs_super_block, s_magic); + + if (blkid_probe_set_magic(pr, magoff, sizeof(sb->s_magic), + (unsigned char *) &sb->s_magic)) + return 1; + + return 0; +} + +const struct blkid_idinfo nilfs2_idinfo = +{ + .name = "nilfs2", + .usage = BLKID_USAGE_FILESYSTEM, + .probefunc = probe_nilfs2, + /* default min.size is 128MiB, but 1MiB for "mkfs.nilfs2 -b 1024 -B 16" */ + .minsz = (1024 * 1024), + .magics = BLKID_NONE_MAGIC +}; |