nilfs2: implement fallback for super root search

[karo-tx-linux.git] / fs / nilfs2 / segbuf.h

diff --git a/fs/nilfs2/segbuf.h b/fs/nilfs2/segbuf.h
index 94dfd3517bc0f5f8f96f0d4efc4588a0ff7dc775..b04f08cc23976a0611a7983de243eade0049fcc1 100644 (file)
--- a/fs/nilfs2/segbuf.h
+++ b/fs/nilfs2/segbuf.h
@@ -37,6 +37,7 @@
  * @sumbytes: Byte count of segment summary
  * @nfileblk: Total number of file blocks
  * @seg_seq: Segment sequence number
+ * @cno: Checkpoint number
  * @ctime: Creation time
  * @next: Block number of the next full segment
  */
@@ -48,21 +49,11 @@ struct nilfs_segsum_info {
        unsigned long           sumbytes;
        unsigned long           nfileblk;
        u64                     seg_seq;
+       __u64                   cno;
        time_t                  ctime;
        sector_t                next;
 };
 
-/* macro for the flags */
-#define NILFS_SEG_HAS_SR(sum)    ((sum)->flags & NILFS_SS_SR)
-#define NILFS_SEG_LOGBGN(sum)    ((sum)->flags & NILFS_SS_LOGBGN)
-#define NILFS_SEG_LOGEND(sum)    ((sum)->flags & NILFS_SS_LOGEND)
-#define NILFS_SEG_DSYNC(sum)     ((sum)->flags & NILFS_SS_SYNDT)
-#define NILFS_SEG_SIMPLEX(sum) \
-       (((sum)->flags & (NILFS_SS_LOGBGN | NILFS_SS_LOGEND)) == \
-        (NILFS_SS_LOGBGN | NILFS_SS_LOGEND))
-
-#define NILFS_SEG_EMPTY(sum)   ((sum)->nblocks == (sum)->nsumblk)
-
 /**
  * struct nilfs_segment_buffer - Segment buffer
  * @sb_super: back pointer to a superblock struct
@@ -76,6 +67,7 @@ struct nilfs_segsum_info {
  * @sb_rest_blocks: Number of residual blocks in the current segment
  * @sb_segsum_buffers: List of buffers for segment summaries
  * @sb_payload_buffers: List of buffers for segment payload
+ * @sb_super_root: Pointer to buffer storing a super root block (if exists)
  * @sb_nbio: Number of flying bio requests
  * @sb_err: I/O error status
  * @sb_bio_event: Completion event of log writing
@@ -95,6 +87,7 @@ struct nilfs_segment_buffer {
        /* Buffers */
        struct list_head        sb_segsum_buffers;
        struct list_head        sb_payload_buffers; /* including super root */
+       struct buffer_head     *sb_super_root;
 
        /* io status */
        int                     sb_nbio;
@@ -121,9 +114,8 @@ struct nilfs_segment_buffer {
                    b_assoc_buffers))
 #define NILFS_SEGBUF_BH_IS_LAST(bh, head)  ((bh)->b_assoc_buffers.next == head)
 
+extern struct kmem_cache *nilfs_segbuf_cachep;
 
-int __init nilfs_init_segbuf_cache(void);
-void nilfs_destroy_segbuf_cache(void);
 struct nilfs_segment_buffer *nilfs_segbuf_new(struct super_block *);
 void nilfs_segbuf_free(struct nilfs_segment_buffer *);
 void nilfs_segbuf_map(struct nilfs_segment_buffer *, __u64, unsigned long,
@@ -132,13 +124,24 @@ void nilfs_segbuf_map_cont(struct nilfs_segment_buffer *segbuf,
                           struct nilfs_segment_buffer *prev);
 void nilfs_segbuf_set_next_segnum(struct nilfs_segment_buffer *, __u64,
                                  struct the_nilfs *);
-int nilfs_segbuf_reset(struct nilfs_segment_buffer *, unsigned, time_t);
+int nilfs_segbuf_reset(struct nilfs_segment_buffer *, unsigned, time_t, __u64);
 int nilfs_segbuf_extend_segsum(struct nilfs_segment_buffer *);
 int nilfs_segbuf_extend_payload(struct nilfs_segment_buffer *,
                                struct buffer_head **);
 void nilfs_segbuf_fill_in_segsum(struct nilfs_segment_buffer *);
-void nilfs_segbuf_fill_in_segsum_crc(struct nilfs_segment_buffer *, u32);
-void nilfs_segbuf_fill_in_data_crc(struct nilfs_segment_buffer *, u32);
+
+static inline int nilfs_segbuf_simplex(struct nilfs_segment_buffer *segbuf)
+{
+       unsigned int flags = segbuf->sb_sum.flags;
+
+       return (flags & (NILFS_SS_LOGBGN | NILFS_SS_LOGEND)) ==
+               (NILFS_SS_LOGBGN | NILFS_SS_LOGEND);
+}
+
+static inline int nilfs_segbuf_empty(struct nilfs_segment_buffer *segbuf)
+{
+       return segbuf->sb_sum.nblocks == segbuf->sb_sum.nsumblk;
+}
 
 static inline void
 nilfs_segbuf_add_segsum_buffer(struct nilfs_segment_buffer *segbuf,
@@ -171,6 +174,7 @@ void nilfs_truncate_logs(struct list_head *logs,
                         struct nilfs_segment_buffer *last);
 int nilfs_write_logs(struct list_head *logs, struct the_nilfs *nilfs);
 int nilfs_wait_on_logs(struct list_head *logs);
+void nilfs_add_checksums_on_logs(struct list_head *logs, u32 seed);
 
 static inline void nilfs_destroy_logs(struct list_head *logs)
 {