From: NeilBrown <neilb@suse.de>
Date: Sat, 14 Aug 2010 05:16:37 +0000 (+1000)
Subject: Change when orphan blocks are refcounted.
X-Git-Url: http://git.neil.brown.name/?a=commitdiff_plain;h=0b5cc41c58630d28bb04d3986a511093f2646ea0;p=LaFS.git

Change when orphan blocks are refcounted.

Count when while B_Orphan is set, rather than while on a list.

This gives us some freedom to do different things with the list,
and ensures that we never lose the flag by the block disappearing.

Signed-off-by: NeilBrown <neilb@suse.de>
---

diff --git a/lafs.h b/lafs.h
index 501cc5c..17a8e27 100644
--- a/lafs.h
+++ b/lafs.h
@@ -662,7 +662,6 @@ int lafs_make_orphan(struct fs *fs, struct datablock *db, struct inode *ino);
 int lafs_make_orphan_nb(struct fs *fs, struct datablock *db, struct inode *ino);
 void lafs_orphan_release(struct fs *fs, struct datablock *b, struct inode *ino);
 long lafs_run_orphans(struct fs *fs);
-int lafs_drop_orphan(struct fs *fs, struct datablock *db);
 void lafs_add_orphan(struct fs *fs, struct datablock *db);
 void lafs_orphan_forget(struct fs *fs, struct datablock *db);
 struct datablock *lafs_find_orphan(struct inode *ino);
diff --git a/orphan.c b/orphan.c
index c0bbf45..246e6ea 100644
--- a/orphan.c
+++ b/orphan.c
@@ -90,8 +90,8 @@ void lafs_dump_orphans(void)
  *         There are "om->reserved" of these, typically all on the one block.
  * "orphan"   This is a block in the orphan file which holds an orphan
  *         record for some committed orphan.  ->orphan_slot points here.
- * "orphan_list" This is a block (not in orphan file) which is an orphan, is
- *         on the ->pending_orphans list and has a record in the orphan file.
+ * "orphan_flag" This is a block (not in orphan file) which is an orphan, and
+ *         has the B_Orphan flag set.
  * "orphanx", "orphan_release", "orphan_release2", "orphan_move"
  * "orphan_fs", "orphan_ino", "orphan_blk"   Temporary references
  */
@@ -169,6 +169,7 @@ static void orphan_commit(struct fs *fs, struct datablock *b, struct datablock *
 	/* Committed to being an orphan now */
 	b->orphan_slot = om->nextfree++;
 	set_bit(B_Orphan, &b->b.flags);
+	getdref(b, MKREF(orphan_flag));
 	lafs_add_orphan(fs, b);
 
 	dprintk("%p->orphan_slot=%d (%lu,%lu,%lu) %s\n", b, b->orphan_slot,
@@ -302,6 +303,7 @@ int lafs_make_orphan_nb(struct fs *fs, struct datablock *db, struct inode *ino)
 	return err;
 }
 
+static int lafs_drop_orphan(struct fs *fs, struct datablock *db);
 /*
  * When any processing of an orphan makes it not an orphan any more
  * (e.g. link is created for a file, directory block is cleaned)
@@ -431,6 +433,7 @@ void lafs_orphan_release(struct fs *fs, struct datablock *b, struct inode *ino)
 	clear_bit(B_Orphan, &b->b.flags);
 	iput(ino);
 	lafs_drop_orphan(fs, b);
+	putdref(b, MKREF(orphan_flag));
 
 	/* Now drop the reservation we just synthesised */
 	orphan_abort(fs);
@@ -574,7 +577,6 @@ int lafs_drop_orphan(struct fs *fs, struct datablock *db)
 	} else {
 		list_del_init(&db->orphans);
 		spin_unlock(&fs->lock);
-		putdref(db, MKREF(orphan_list));
 		return 1;
 	}
 }
@@ -589,10 +591,9 @@ void lafs_add_orphan(struct fs *fs, struct datablock *db)
 	 */
 	LAFS_BUG(!test_bit(B_Orphan, &db->b.flags), &db->b);
 	spin_lock(&fs->lock);
-	if (list_empty(&db->orphans)) {
+	if (list_empty(&db->orphans))
 		list_add_tail(&db->orphans, &fs->pending_orphans);
-		getdref(db, MKREF(orphan_list));
-	}
+
 	spin_unlock(&fs->lock);
 	lafs_wake_thread(fs);
 }
@@ -603,12 +604,9 @@ void lafs_orphan_forget(struct fs *fs, struct datablock *db)
 	 * it just now.  When we do, lafs_add_orphan will be called */
 	LAFS_BUG(!test_bit(B_Orphan, &db->b.flags), &db->b);
 	spin_lock(&fs->lock);
-	if (!list_empty(&db->orphans)) {
+	if (!list_empty(&db->orphans))
 		list_del_init(&db->orphans);
-		spin_unlock(&fs->lock);
-		putdref(db, MKREF(orphan_list));
-	} else
-		spin_unlock(&fs->lock);
+	spin_unlock(&fs->lock);
 }
 
 struct datablock *lafs_find_orphan(struct inode *ino)