nilfs2: add iterator for segment buffers

This adds a few iterator functions for segment buffers to make it easy
to handle multiple series of logs.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

1 files changed, 12 insertions, 39 deletions

diff --git a/fs/nilfs2/segment.c b/fs/nilfs2/segment.c
index 4422cdae112a..689deb9d41d1 100644
--- a/fs/nilfs2/segment.c
+++ b/fs/nilfs2/segment.c
@@ -1276,7 +1276,7 @@ static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode)
 static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci,
                                             struct the_nilfs *nilfs)
 {
-        struct nilfs_segment_buffer *segbuf, *n;
+        struct nilfs_segment_buffer *segbuf;
         __u64 nextnum;
         int err;
 
@@ -1313,18 +1313,14 @@ static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci,
         nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs);
 
         /* truncating segment buffers */
-        list_for_each_entry_safe_continue(segbuf, n, &sci->sc_segbufs,
-                                          sb_list) {
-                list_del_init(&segbuf->sb_list);
-                nilfs_segbuf_free(segbuf);
-        }
+        nilfs_truncate_logs(&sci->sc_segbufs, segbuf);
         return 0;
 }
 
 static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci,
                                          struct the_nilfs *nilfs, int nadd)
 {
-        struct nilfs_segment_buffer *segbuf, *prev, *n;
+        struct nilfs_segment_buffer *segbuf, *prev;
         struct inode *sufile = nilfs->ns_sufile;
         __u64 nextnextnum;
         LIST_HEAD(list);
@@ -1369,12 +1365,11 @@ static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci,
  failed_segbuf:
         nilfs_segbuf_free(segbuf);
  failed:
-        list_for_each_entry_safe(segbuf, n, &list, sb_list) {
+        list_for_each_entry(segbuf, &list, sb_list) {
                 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
                 WARN_ON(ret); /* never fails */
-                list_del_init(&segbuf->sb_list);
-                nilfs_segbuf_free(segbuf);
         }
+        nilfs_destroy_logs(&list);
         return err;
 }
 
@@ -1411,27 +1406,6 @@ static void nilfs_segctor_free_incomplete_segments(struct nilfs_sc_info *sci,
         }
 }
 
-static void nilfs_segctor_clear_segment_buffers(struct nilfs_sc_info *sci)
-{
-        struct nilfs_segment_buffer *segbuf;
-
-        list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list)
-                nilfs_segbuf_clear(segbuf);
-        sci->sc_super_root = NULL;
-}
-
-static void nilfs_segctor_destroy_segment_buffers(struct nilfs_sc_info *sci)
-{
-        struct nilfs_segment_buffer *segbuf;
-
-        while (!list_empty(&sci->sc_segbufs)) {
-                segbuf = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
-                list_del_init(&segbuf->sb_list);
-                nilfs_segbuf_free(segbuf);
-        }
-        /* sci->sc_curseg = NULL; */
-}
-
 static void nilfs_segctor_end_construction(struct nilfs_sc_info *sci,
                                            struct the_nilfs *nilfs, int err)
 {
@@ -1447,7 +1421,8 @@ static void nilfs_segctor_end_construction(struct nilfs_sc_info *sci,
                         WARN_ON(ret); /* do not happen */
                 }
         }
-        nilfs_segctor_clear_segment_buffers(sci);
+        nilfs_clear_logs(&sci->sc_segbufs);
+        sci->sc_super_root = NULL;
 }
 
 static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci,
@@ -1490,17 +1465,15 @@ static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci,
                                             struct nilfs_segment_buffer *last,
                                             struct inode *sufile)
 {
-        struct nilfs_segment_buffer *segbuf = last, *n;
+        struct nilfs_segment_buffer *segbuf = last;
         int ret;
 
-        list_for_each_entry_safe_continue(segbuf, n, &sci->sc_segbufs,
-                                          sb_list) {
-                list_del_init(&segbuf->sb_list);
+        list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) {
                 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks;
                 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
                 WARN_ON(ret);
-                nilfs_segbuf_free(segbuf);
         }
+        nilfs_truncate_logs(&sci->sc_segbufs, last);
 }
 
 
@@ -1539,7 +1512,7 @@ static int nilfs_segctor_collect(struct nilfs_sc_info *sci,
                                                         NULL);
                         WARN_ON(err); /* do not happen */
                 }
-                nilfs_segctor_clear_segment_buffers(sci);
+                nilfs_clear_logs(&sci->sc_segbufs);
 
                 err = nilfs_segctor_extend_segments(sci, nilfs, nadd);
                 if (unlikely(err))
@@ -2179,7 +2152,7 @@ static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode)
         } while (sci->sc_stage.scnt != NILFS_ST_DONE);
 
  out:
-        nilfs_segctor_destroy_segment_buffers(sci);
+        nilfs_destroy_logs(&sci->sc_segbufs);
         nilfs_segctor_check_out_files(sci, sbi);
         return err;