/* * volume_id - reads filesystem label and uuid * * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org> * Copyright (C) 2012 S-G Bergh <sgb@systemasis.org> * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ //kbuild:lib-$(CONFIG_FEATURE_VOLUMEID_NILFS) += nilfs.o //config: //config:config FEATURE_VOLUMEID_NILFS //config: bool "nilfs filesystem" //config: default y //config: depends on VOLUMEID //config: help //config: NILFS is a New Implementation of a Log-Structured File System (LFS) //config: that supports continuous snapshots. This provides features like //config: versioning of the entire filesystem, restoration of files that //config: were deleted a few minutes ago. NILFS keeps consistency like //config: conventional LFS, so it provides quick recovery after system crashes. //config: //config: The possible use of NILFS includes versioning, tamper detection, //config: SOX compliance logging, and so forth. It can serve as an alternative //config: filesystem for Linux desktop environment, or as a basis of advanced //config: storage appliances. //config: #include "volume_id_internal.h" #define NILFS_UUID_SIZE 16 #define NILFS_LABEL_SIZE 80 #define NILFS_SB1_OFFSET 0x400 #define NILFS_SB2_OFFSET 0x1000 #define NILFS_MAGIC 0x3434 struct nilfs2_super_block { /* 0x00 */ uint32_t s_rev_level; // Major revision level. /* 0x04 */ uint16_t s_minor_rev_level; // Minor revision level. /* 0x06 */ uint16_t s_magic; // Magic signature. /* 0x08 */ uint16_t s_bytes; /* 0x0A */ uint16_t s_flags; /* 0x0C */ uint32_t s_crc_seed; /* 0x10 */ uint32_t s_sum; /* 0x14 */ uint32_t s_log_block_size; /* 0x18 */ uint64_t s_nsegments; /* 0x20 */ uint64_t s_dev_size; // Block device size in bytes. /* 0x28 */ uint64_t s_first_data_block; /* 0x30 */ uint32_t s_blocks_per_segment; /* 0x34 */ uint32_t s_r_segments_percentage; /* 0x38 */ uint64_t s_last_cno; /* 0x40 */ uint64_t s_last_pseg; /* 0x48 */ uint64_t s_last_seq; /* 0x50 */ uint64_t s_free_blocks_count; /* 0x58 */ uint64_t s_ctime; /* 0x60 */ uint64_t s_mtime; /* 0x68 */ uint64_t s_wtime; /* 0x70 */ uint16_t s_mnt_count; /* 0x72 */ uint16_t s_max_mnt_count; /* 0x74 */ uint16_t s_state; /* 0x76 */ uint16_t s_errors; /* 0x78 */ uint64_t s_lastcheck; /* 0x80 */ uint32_t s_checkinterval; /* 0x84 */ uint32_t s_creator_os; /* 0x88 */ uint16_t s_def_resuid; /* 0x8A */ uint16_t s_def_resgid; /* 0x8C */ uint32_t s_first_ino; /* 0x90 */ uint16_t s_inode_size; /* 0x92 */ uint16_t s_dat_entry_size; /* 0x94 */ uint16_t s_checkpoint_size; /* 0x96 */ uint16_t s_segment_usage_size; /* 0x98 */ uint8_t s_uuid[NILFS_UUID_SIZE]; // 128-bit UUID for volume. /* 0xA8 */ uint8_t s_volume_name[NILFS_LABEL_SIZE]; // Volume label. /* 0xF8 */ // ... } PACKED; int FAST_FUNC volume_id_probe_nilfs(struct volume_id *id /*,uint64_t off*/) { struct nilfs2_super_block *sb; // Primary super block dbg("nilfs: probing at offset 0x%x", NILFS_SB1_OFFSET); sb = volume_id_get_buffer(id, NILFS_SB1_OFFSET, sizeof(*sb)); if (sb == NULL) return -1; if (sb->s_magic != NILFS_MAGIC) return -1; // The secondary superblock is not always used, so ignore it for now. // When used it is at 4K from the end of the partition (sb->s_dev_size - NILFS_SB2_OFFSET). volume_id_set_label_string(id, sb->s_volume_name, NILFS_LABEL_SIZE < VOLUME_ID_LABEL_SIZE ? NILFS_LABEL_SIZE : VOLUME_ID_LABEL_SIZE); volume_id_set_uuid(id, sb->s_uuid, UUID_DCE); if (sb->s_rev_level == 2) IF_FEATURE_BLKID_TYPE(id->type = "nilfs2"); return 0; }