From: Sage Weil <sage@newdream.net>
Date: Wed, 24 Jun 2009 19:55:00 +0000 (-0700)
Subject: osd: make object delete not remove _head if there are clones
X-Git-Tag: v0.10~161
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=1fd46cc3e889daa7628f093fdc1c0012ebc1c3d7;p=ceph.git

osd: make object delete not remove _head if there are clones

Truncate and rmattrs instead, so we can keep the SnapSet.

Still need to make 'ls' work properly.
---

diff --git a/src/TODO b/src/TODO
index f69ec034e412..c0d9ae463f12 100644
--- a/src/TODO
+++ b/src/TODO
@@ -71,11 +71,6 @@ later
 - rename over old files should flush data, or revert back to old contents
 
 rados
-/ - kill -[io] options
-/ - make 'ls' output to file
-/ - make objecter->list_objects return even with <max entries (i.e., after each non-empty pg)
-/ - verify 'ls' behaves with snaps
-/ - allow put from stdin: 'echo foo | rados -p mypool put foo -'
 - perl swig wrapper
 - 'rados call foo.bar'?
 - merge pgs
@@ -139,6 +134,7 @@ btrfs
 - ioctl to pull out data csum?
 
 osd
+- need to store SnapSet somewhere other than _head, to avoid stat/getxattr on ls to check head_exists.
 - segregate backlog from log ondisk?
 - preserve pg logs on disk for longer period
 - make scrub interruptible
diff --git a/src/osd/ReplicatedPG.cc b/src/osd/ReplicatedPG.cc
index c792a97adc48..75585b608ab9 100644
--- a/src/osd/ReplicatedPG.cc
+++ b/src/osd/ReplicatedPG.cc
@@ -1161,20 +1161,25 @@ int ReplicatedPG::do_osd_ops(OpContext *ctx, vector<OSDOp>& ops,
     
     case CEPH_OSD_OP_DELETE:
       { // delete
-	t.remove(info.pgid.to_coll(), soid);
-	if (oi.snapset.clones.size()) {
-	  snapid_t newest = *oi.snapset.clones.rbegin();
-	  add_interval_usage(oi.snapset.clone_overlap[newest], info.stats);
-	  oi.snapset.clone_overlap.erase(newest);  // ok, redundant.
-	}
 	if (ctx->obs->exists) {
 	  info.stats.num_objects--;
 	  info.stats.num_bytes -= oi.size;
 	  info.stats.num_kb -= SHIFT_ROUND_UP(oi.size, 10);
 	  oi.size = 0;
-	  ctx->obs->exists = false;
 	  oi.snapset.head_exists = false;
 	}      
+	if (oi.snapset.clones.size()) {
+	  snapid_t newest = *oi.snapset.clones.rbegin();
+	  add_interval_usage(oi.snapset.clone_overlap[newest], info.stats);
+	  oi.snapset.clone_overlap.erase(newest);  // ok, redundant.
+
+	  // truncate and kill attrs, but do not delete
+	  t.truncate(info.pgid.to_coll(), soid, 0);
+	  t.rmattrs(info.pgid.to_coll(), soid);
+	} else {
+	  t.remove(info.pgid.to_coll(), soid);  // no clones, delete!
+	  ctx->obs->exists = false;
+	}
       }
       break;