From: NeilBrown <neilb@suse.de>
Date: Wed, 2 Sep 2009 00:09:52 +0000 (+1000)
Subject: Remove special handling for i_nlink when reading inodes.
X-Git-Url: http://git.neil.brown.name/?a=commitdiff_plain;h=f0ddcc2c1d2c8c49942bddac0781d4c8d57c482e;p=LaFS.git

Remove special handling for i_nlink when reading inodes.

This was never "right" and is confusing orphan handling.
We should not lose those blocks anymore but if we do we need a better
fix.
---

diff --git a/dir.c b/dir.c
index 7ee11b5..e336ef8 100644
--- a/dir.c
+++ b/dir.c
@@ -620,9 +620,6 @@ lafs_create(struct inode *dir, struct dentry *de, int mode,
  abort:
 	lafs_cluster_update_abort(&uh);
 	dir_create_abort(&doh);
-	/* This is needed because import_inode sets it to 1
-	 * to avoid something silly.  Needs FIXME */
-	ino->i_nlink = 0;
 	iput(ino);
 	clear_bit(B_PinPending, &db->b.flags);
 	putdref(db, MKREF(inode_new));
@@ -907,9 +904,6 @@ lafs_symlink(struct inode *dir, struct dentry *de,
 	clear_bit(B_PinPending, &b->b.flags);
 	putdref(b, MKREF(symlink));
 	dir_create_abort(&doh);
-	/* This is needed because import_inode sets it to 1
-	 * to avoid something silly.  Needs FIXME */
-	ino->i_nlink = 0;
 	lafs_cluster_update_abort(&uh);
 	iput(ino);
 	return err;
@@ -972,10 +966,7 @@ lafs_mkdir(struct inode *dir, struct dentry *de, int mode)
  abort:
 	dir_create_abort(&doh);
 	lafs_cluster_update_abort(&uh);
-	/* This is needed because import_inode sets it to 1
-	 * to avoid something silly.  Needs FIXME */
-	ino->i_nlink = 0;
-	iput(ino);
+		iput(ino);
 	clear_bit(B_PinPending, &inodb->b.flags);
 	putdref(inodb, MKREF(inode_new));
 	return err;
@@ -1051,9 +1042,6 @@ lafs_mknod(struct inode *dir, struct dentry *de, int mode,
  abort:
 	dir_create_abort(&doh);
 	lafs_cluster_update_abort(&uh);
-	/* This is needed because import_inode sets it to 1
-	 * to avoid something silly.  Needs FIXME */
-	ino->i_nlink = 0;
 	iput(ino);
 	clear_bit(B_PinPending, &inodb->b.flags);
 	putdref(inodb, MKREF(inode_new));
diff --git a/inode.c b/inode.c
index d6e916d..4bf4fda 100644
--- a/inode.c
+++ b/inode.c
@@ -203,9 +203,16 @@ lafs_import_inode(struct inode *ino, struct datablock *b)
 		ino->i_size = le64_to_cpu(l->size);
 		i->parent = le32_to_cpu(l->parent);
 		ino->i_nlink = le32_to_cpu(l->linkcount);
-/*FIXME when rollforward finds nlink=0 inode,
-  it keeps losing them... */
-if (!ino->i_nlink) ino->i_nlink = 1;
+		if (ino->i_nlink == 0 && list_empty(&b->orphans)) {
+			/* Pop this block on the orphan list just in case */
+			struct fs *fs = fs_from_inode(ino);
+			spin_lock(&fs->lock);
+			if (list_empty(&b->orphans)) {
+				list_add_tail(&b->orphans, &fs->pending_orphans);
+				getdref(b, MKREF(orphan_list));
+			}
+			spin_unlock(&fs->lock);
+		}
 
 		dprintk("  mode = 0%o uid %d size %lld\n",
 		       ino->i_mode, ino->i_uid, ino->i_size);
diff --git a/roll.c b/roll.c
index 934f9d7..f2bea8f 100644
--- a/roll.c
+++ b/roll.c
@@ -219,6 +219,16 @@ roll_mini(struct fs *fs, int fsnum, int inum, int trunc, int flg,
 		memcpy(buf+offset, data, len);
 		unmap_dblock(db, buf);
 		err = lafs_import_inode(inode, db);
+		/* WE borrow the orphan list to keep a reference on
+		 * this inode until all processing is finished
+		 * to make sure inodes that are about to get linked
+		 * to get deleted early
+		 */
+		if (list_empty(&db->orphans)) {
+			list_add(&db->orphans, &fs->pending_orphans);
+			igrab(inode);
+			getdref(db, MKREF(roll_orphan));
+		}
 		putdref(db, MKREF(roll));
 		break;
 	}
@@ -507,6 +517,16 @@ static int roll_forward(struct fs *fs)
 	put_page(p);
 	put_page(pg);
 	kfree(buf);
+
+	/* Now we release all the nlink==0 inode that we found */
+	while (!list_empty(&fs->pending_orphans)) {
+		struct datablock *db = list_entry(fs->pending_orphans.next,
+						  struct datablock,
+						  orphans);
+		list_del_init(&db->orphans);
+		iput(db->my_inode);
+		putdref(db, MKREF(roll_orphan));
+	}
 	fs->rolled = 1;
 	return err;
 }