nilfs2: extend nilfs_sustat ioctl struct

This adds a new argument to the nilfs_sustat structure.

The extended field allows to delete volatile active state of segments,
which was needed to protect freshly-created segments from garbage
collection but has confused code dealing with segments.  This
extension alleviates the mess and gives room for further
simplifications.

The volatile active flag is not persistent, so it's eliminable on this
occasion without affecting compatibility other than the ioctl change.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 3 deletions

diff --git a/fs/nilfs2/the_nilfs.h b/fs/nilfs2/the_nilfs.h
index 75da37306964..af566e78f7af 100644
--- a/fs/nilfs2/the_nilfs.h
+++ b/fs/nilfs2/the_nilfs.h
@@ -51,7 +51,6 @@ enum {
  * @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_supers: list of nilfs super block structs
  * @ns_seg_seq: segment sequence counter
  * @ns_segnum: index number of the latest full segment.
@@ -65,6 +64,7 @@ enum {
  * @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
@@ -103,7 +103,6 @@ struct the_nilfs {
          */
         struct buffer_head     *ns_sbh;
         struct nilfs_super_block *ns_sbp;
-        struct list_head        ns_used_segments;
         unsigned                ns_mount_state;
         struct list_head        ns_supers;
 
@@ -132,6 +131,7 @@ struct the_nilfs {
         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;
@@ -188,7 +188,6 @@ 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 *);