* @ns_sem: semaphore for shared states
* @ns_writer_mutex: mutex protecting ns_writer attach/detach
* @ns_writer_refcount: number of referrers on ns_writer
- * @ns_sbh: buffer head of the on-disk super block
- * @ns_sbp: pointer to the super block data
- * @ns_used_segments: list of full segments in volatile active state
+ * @ns_sbh: buffer heads of on-disk super blocks
+ * @ns_sbp: pointers to super block data
+ * @ns_sbwtime: previous write time of super blocks
+ * @ns_sbsize: size of valid data in super block
* @ns_supers: list of nilfs super block structs
* @ns_seg_seq: segment sequence counter
* @ns_segnum: index number of the latest full segment.
* @ns_last_pseg: start block number of the latest segment
* @ns_last_seq: sequence value of the latest segment
* @ns_last_cno: checkpoint number of the latest segment
+ * @ns_prot_seq: least sequence number of segments which must not be reclaimed
* @ns_free_segments_count: counter of free segments
* @ns_segctor_sem: segment constructor semaphore
* @ns_dat: DAT file inode
* - protecting s_dirt in the super_block struct
* (see nilfs_write_super) and the following fields.
*/
- struct buffer_head *ns_sbh;
- struct nilfs_super_block *ns_sbp;
- struct list_head ns_used_segments;
+ struct buffer_head *ns_sbh[2];
+ struct nilfs_super_block *ns_sbp[2];
+ time_t ns_sbwtime[2];
+ unsigned ns_sbsize;
unsigned ns_mount_state;
struct list_head ns_supers;
sector_t ns_last_pseg;
u64 ns_last_seq;
__u64 ns_last_cno;
+ u64 ns_prot_seq;
unsigned long ns_free_segments_count;
struct rw_semaphore ns_segctor_sem;
THE_NILFS_FNS(LOADED, loaded)
THE_NILFS_FNS(DISCONTINUED, discontinued)
+/* Minimum interval of periodical update of superblocks (in seconds) */
+#define NILFS_SB_FREQ 10
+#define NILFS_ALTSB_FREQ 60 /* spare superblock */
+
void nilfs_set_last_segment(struct the_nilfs *, sector_t, u64, __u64);
struct the_nilfs *alloc_nilfs(struct block_device *);
void put_nilfs(struct the_nilfs *);
int init_nilfs(struct the_nilfs *, struct nilfs_sb_info *, char *);
int load_nilfs(struct the_nilfs *, struct nilfs_sb_info *);
int nilfs_count_free_blocks(struct the_nilfs *, sector_t *);
-void nilfs_dispose_used_segments(struct the_nilfs *);
int nilfs_checkpoint_is_mounted(struct the_nilfs *, __u64, int);
int nilfs_near_disk_full(struct the_nilfs *);
+void nilfs_fall_back_super_block(struct the_nilfs *);
+void nilfs_swap_super_block(struct the_nilfs *);
static inline void get_nilfs(struct the_nilfs *nilfs)
return cno;
}
+static inline int nilfs_segment_is_active(struct the_nilfs *nilfs, __u64 n)
+{
+ return n == nilfs->ns_segnum || n == nilfs->ns_nextnum;
+}
+
#endif /* _THE_NILFS_H */