diff options
Diffstat (limited to 'fs/ubifs/ubifs-media.h')
| -rw-r--r-- | fs/ubifs/ubifs-media.h | 67 |
1 files changed, 50 insertions, 17 deletions
diff --git a/fs/ubifs/ubifs-media.h b/fs/ubifs/ubifs-media.h index b25fc36cf72..e24380cf46e 100644 --- a/fs/ubifs/ubifs-media.h +++ b/fs/ubifs/ubifs-media.h @@ -36,9 +36,31 @@ /* UBIFS node magic number (must not have the padding byte first or last) */ #define UBIFS_NODE_MAGIC 0x06101831 -/* UBIFS on-flash format version */ +/* + * UBIFS on-flash format version. This version is increased when the on-flash + * format is changing. If this happens, UBIFS is will support older versions as + * well. But older UBIFS code will not support newer formats. Format changes + * will be rare and only when absolutely necessary, e.g. to fix a bug or to add + * a new feature. + * + * UBIFS went into mainline kernel with format version 4. The older formats + * were development formats. + */ #define UBIFS_FORMAT_VERSION 4 +/* + * Read-only compatibility version. If the UBIFS format is changed, older UBIFS + * implementations will not be able to mount newer formats in read-write mode. + * However, depending on the change, it may be possible to mount newer formats + * in R/O mode. This is indicated by the R/O compatibility version which is + * stored in the super-block. + * + * This is needed to support boot-loaders which only need R/O mounting. With + * this flag it is possible to do UBIFS format changes without a need to update + * boot-loaders. + */ +#define UBIFS_RO_COMPAT_VERSION 0 + /* Minimum logical eraseblock size in bytes */ #define UBIFS_MIN_LEB_SZ (15*1024) @@ -53,7 +75,7 @@ /* * If compressed data length is less than %UBIFS_MIN_COMPRESS_DIFF bytes - * shorter than uncompressed data length, UBIFS preferes to leave this data + * shorter than uncompressed data length, UBIFS prefers to leave this data * node uncompress, because it'll be read faster. */ #define UBIFS_MIN_COMPRESS_DIFF 64 @@ -113,6 +135,13 @@ /* The key is always at the same position in all keyed nodes */ #define UBIFS_KEY_OFFSET offsetof(struct ubifs_ino_node, key) +/* Garbage collector journal head number */ +#define UBIFS_GC_HEAD 0 +/* Base journal head number */ +#define UBIFS_BASE_HEAD 1 +/* Data journal head number */ +#define UBIFS_DATA_HEAD 2 + /* * LEB Properties Tree node types. * @@ -379,9 +408,11 @@ enum { * Superblock flags. * * UBIFS_FLG_BIGLPT: if "big" LPT model is used if set + * UBIFS_FLG_SPACE_FIXUP: first-mount "fixup" of free space within LEBs needed */ enum { UBIFS_FLG_BIGLPT = 0x02, + UBIFS_FLG_SPACE_FIXUP = 0x04, }; /** @@ -405,7 +436,7 @@ struct ubifs_ch { __u8 node_type; __u8 group_type; __u8 padding[2]; -} __attribute__ ((packed)); +} __packed; /** * union ubifs_dev_desc - device node descriptor. @@ -419,7 +450,7 @@ struct ubifs_ch { union ubifs_dev_desc { __le32 new; __le64 huge; -} __attribute__ ((packed)); +} __packed; /** * struct ubifs_ino_node - inode node. @@ -480,7 +511,7 @@ struct ubifs_ino_node { __le16 compr_type; __u8 padding2[26]; /* Watch 'zero_ino_node_unused()' if changing! */ __u8 data[]; -} __attribute__ ((packed)); +} __packed; /** * struct ubifs_dent_node - directory entry node. @@ -505,7 +536,7 @@ struct ubifs_dent_node { __le16 nlen; __u8 padding2[4]; /* Watch 'zero_dent_node_unused()' if changing! */ __u8 name[]; -} __attribute__ ((packed)); +} __packed; /** * struct ubifs_data_node - data node. @@ -526,7 +557,7 @@ struct ubifs_data_node { __le16 compr_type; __u8 padding[2]; /* Watch 'zero_data_node_unused()' if changing! */ __u8 data[]; -} __attribute__ ((packed)); +} __packed; /** * struct ubifs_trun_node - truncation node. @@ -546,7 +577,7 @@ struct ubifs_trun_node { __u8 padding[12]; /* Watch 'zero_trun_node_unused()' if changing! */ __le64 old_size; __le64 new_size; -} __attribute__ ((packed)); +} __packed; /** * struct ubifs_pad_node - padding node. @@ -557,7 +588,7 @@ struct ubifs_trun_node { struct ubifs_pad_node { struct ubifs_ch ch; __le32 pad_len; -} __attribute__ ((packed)); +} __packed; /** * struct ubifs_sb_node - superblock node. @@ -586,6 +617,7 @@ struct ubifs_pad_node { * @padding2: reserved for future, zeroes * @time_gran: time granularity in nanoseconds * @uuid: UUID generated when the file system image was created + * @ro_compat_version: UBIFS R/O compatibility version */ struct ubifs_sb_node { struct ubifs_ch ch; @@ -612,8 +644,9 @@ struct ubifs_sb_node { __le64 rp_size; __le32 time_gran; __u8 uuid[16]; - __u8 padding2[3972]; -} __attribute__ ((packed)); + __le32 ro_compat_version; + __u8 padding2[3968]; +} __packed; /** * struct ubifs_mst_node - master node. @@ -680,7 +713,7 @@ struct ubifs_mst_node { __le32 idx_lebs; __le32 leb_cnt; __u8 padding[344]; -} __attribute__ ((packed)); +} __packed; /** * struct ubifs_ref_node - logical eraseblock reference node. @@ -696,7 +729,7 @@ struct ubifs_ref_node { __le32 offs; __le32 jhead; __u8 padding[28]; -} __attribute__ ((packed)); +} __packed; /** * struct ubifs_branch - key/reference/length branch @@ -710,7 +743,7 @@ struct ubifs_branch { __le32 offs; __le32 len; __u8 key[]; -} __attribute__ ((packed)); +} __packed; /** * struct ubifs_idx_node - indexing node. @@ -724,7 +757,7 @@ struct ubifs_idx_node { __le16 child_cnt; __le16 level; __u8 branches[]; -} __attribute__ ((packed)); +} __packed; /** * struct ubifs_cs_node - commit start node. @@ -734,7 +767,7 @@ struct ubifs_idx_node { struct ubifs_cs_node { struct ubifs_ch ch; __le64 cmt_no; -} __attribute__ ((packed)); +} __packed; /** * struct ubifs_orph_node - orphan node. @@ -746,6 +779,6 @@ struct ubifs_orph_node { struct ubifs_ch ch; __le64 cmt_no; __le64 inos[]; -} __attribute__ ((packed)); +} __packed; #endif /* __UBIFS_MEDIA_H__ */ |