diff --git a/fs/ceph/ceph_fs.h b/fs/ceph/ceph_fs.h
index 8b194c6..715e39c 100644
--- a/fs/ceph/ceph_fs.h
+++ b/fs/ceph/ceph_fs.h
@@ -19,7 +19,7 @@
  * Ceph release version
  */
 #define CEPH_VERSION_MAJOR 0
-#define CEPH_VERSION_MINOR 19
+#define CEPH_VERSION_MINOR 20
 #define CEPH_VERSION_PATCH 0
 
 #define _CEPH_STRINGIFY(x) #x
@@ -36,7 +36,7 @@
  * client-facing protocol.
  */
 #define CEPH_OSD_PROTOCOL     8 /* cluster internal */
-#define CEPH_MDS_PROTOCOL     9 /* cluster internal */
+#define CEPH_MDS_PROTOCOL    12 /* cluster internal */
 #define CEPH_MON_PROTOCOL     5 /* cluster internal */
 #define CEPH_OSDC_PROTOCOL   24 /* server/client */
 #define CEPH_MDSC_PROTOCOL   32 /* server/client */
@@ -55,10 +55,11 @@
  */
 #define CEPH_FEATURE_UID        1
 #define CEPH_FEATURE_NOSRCADDR  2
+#define CEPH_FEATURE_FLOCK      4
 
 #define CEPH_FEATURE_SUPPORTED_MON  CEPH_FEATURE_UID|CEPH_FEATURE_NOSRCADDR
 #define CEPH_FEATURE_REQUIRED_MON   CEPH_FEATURE_UID
-#define CEPH_FEATURE_SUPPORTED_MDS  CEPH_FEATURE_UID|CEPH_FEATURE_NOSRCADDR
+#define CEPH_FEATURE_SUPPORTED_MDS  CEPH_FEATURE_UID|CEPH_FEATURE_NOSRCADDR|CEPH_FEATURE_FLOCK
 #define CEPH_FEATURE_REQUIRED_MDS   CEPH_FEATURE_UID
 #define CEPH_FEATURE_SUPPORTED_OSD  CEPH_FEATURE_UID|CEPH_FEATURE_NOSRCADDR
 #define CEPH_FEATURE_REQUIRED_OSD   CEPH_FEATURE_UID
@@ -100,6 +101,8 @@
 #define CEPH_AUTH_NONE	 	0x1
 #define CEPH_AUTH_CEPHX	 	0x2
 
+#define CEPH_AUTH_UID_DEFAULT ((__u64) -1)
+
 
 /*********************************************
  * message layer
@@ -137,11 +140,27 @@
 #define CEPH_MSG_CLIENT_SNAP            0x312
 #define CEPH_MSG_CLIENT_CAPRELEASE      0x313
 
+/* pool ops */
+#define CEPH_MSG_POOLOP_REPLY           48
+#define CEPH_MSG_POOLOP                 49
+
+
 /* osd */
 #define CEPH_MSG_OSD_MAP          41
 #define CEPH_MSG_OSD_OP           42
 #define CEPH_MSG_OSD_OPREPLY      43
 
+/* pool operations */
+enum {
+  POOL_OP_CREATE			= 0x01,
+  POOL_OP_DELETE			= 0x02,
+  POOL_OP_AUID_CHANGE			= 0x03,
+  POOL_OP_CREATE_SNAP			= 0x11,
+  POOL_OP_DELETE_SNAP			= 0x12,
+  POOL_OP_CREATE_UNMANAGED_SNAP		= 0x21,
+  POOL_OP_DELETE_UNMANAGED_SNAP		= 0x22,
+};
+
 struct ceph_mon_request_header {
 	__le64 have_version;
 	__le16 session_mon;
@@ -164,6 +183,31 @@
 	struct ceph_statfs st;
 } __attribute__ ((packed));
 
+const char *ceph_pool_op_name(int op);
+
+struct ceph_mon_poolop {
+	struct ceph_mon_request_header monhdr;
+	struct ceph_fsid fsid;
+	__le32 pool;
+	__le32 op;
+	__le64 auid;
+	__le64 snapid;
+	__le32 name_len;
+} __attribute__ ((packed));
+
+struct ceph_mon_poolop_reply {
+	struct ceph_mon_request_header monhdr;
+	struct ceph_fsid fsid;
+	__le32 reply_code;
+	__le32 epoch;
+	char has_data;
+	char data[0];
+} __attribute__ ((packed));
+
+struct ceph_mon_unmanaged_snap {
+	__le64 snapid;
+} __attribute__ ((packed));
+
 struct ceph_osd_getmap {
 	struct ceph_mon_request_header monhdr;
 	struct ceph_fsid fsid;
diff --git a/fs/ceph/ceph_strings.c b/fs/ceph/ceph_strings.c
index 8e4be6a..7890830 100644
--- a/fs/ceph/ceph_strings.c
+++ b/fs/ceph/ceph_strings.c
@@ -10,7 +10,6 @@
 	case CEPH_ENTITY_TYPE_OSD: return "osd";
 	case CEPH_ENTITY_TYPE_MON: return "mon";
 	case CEPH_ENTITY_TYPE_CLIENT: return "client";
-	case CEPH_ENTITY_TYPE_ADMIN: return "admin";
 	case CEPH_ENTITY_TYPE_AUTH: return "auth";
 	default: return "unknown";
 	}
@@ -45,6 +44,7 @@
 	case CEPH_OSD_OP_SETXATTRS: return "setxattrs";
 	case CEPH_OSD_OP_RESETXATTRS: return "resetxattrs";
 	case CEPH_OSD_OP_RMXATTR: return "rmxattr";
+	case CEPH_OSD_OP_CMPXATTR: return "cmpxattr";
 
 	case CEPH_OSD_OP_PULL: return "pull";
 	case CEPH_OSD_OP_PUSH: return "push";
@@ -174,3 +174,24 @@
 	}
 	return "???";
 }
+
+const char *ceph_pool_op_name(int op) {
+  switch (op) {
+  case POOL_OP_CREATE:
+    return "create pool";
+  case POOL_OP_DELETE:
+    return "delete pool";
+  case POOL_OP_AUID_CHANGE:
+    return "change auid";
+  case POOL_OP_CREATE_SNAP:
+    return "create snap";
+  case POOL_OP_DELETE_SNAP:
+    return "delete snap";
+  case POOL_OP_CREATE_UNMANAGED_SNAP:
+    return "create unmanaged snap";
+  case POOL_OP_DELETE_UNMANAGED_SNAP:
+    return "delete unmanaged snap";
+  default:
+    return "unknown";
+  }
+}
diff --git a/fs/ceph/messenger.c b/fs/ceph/messenger.c
index fe75ec7..d18a544 100644
--- a/fs/ceph/messenger.c
+++ b/fs/ceph/messenger.c
@@ -39,18 +39,6 @@
 static void con_work(struct work_struct *);
 static void ceph_fault(struct ceph_connection *con);
 
-const char *ceph_name_type_str(int t)
-{
-	switch (t) {
-	case CEPH_ENTITY_TYPE_MON: return "mon";
-	case CEPH_ENTITY_TYPE_MDS: return "mds";
-	case CEPH_ENTITY_TYPE_OSD: return "osd";
-	case CEPH_ENTITY_TYPE_CLIENT: return "client";
-	case CEPH_ENTITY_TYPE_ADMIN: return "admin";
-	default: return "???";
-	}
-}
-
 /*
  * nicely render a sockaddr as a string.
  */
diff --git a/fs/ceph/messenger.h b/fs/ceph/messenger.h
index e56564f..4e5764c 100644
--- a/fs/ceph/messenger.h
+++ b/fs/ceph/messenger.h
@@ -49,10 +49,8 @@
 					int *skip);
 };
 
-extern const char *ceph_name_type_str(int t);
-
 /* use format string %s%d */
-#define ENTITY_NAME(n) ceph_name_type_str((n).type), le64_to_cpu((n).num)
+#define ENTITY_NAME(n) ceph_entity_type_name((n).type), le64_to_cpu((n).num)
 
 struct ceph_messenger {
 	struct ceph_entity_inst inst;    /* my name+address */
diff --git a/fs/ceph/msgr.h b/fs/ceph/msgr.h
index 6baa8e4f..892a029 100644
--- a/fs/ceph/msgr.h
+++ b/fs/ceph/msgr.h
@@ -50,7 +50,6 @@
 #define CEPH_ENTITY_TYPE_MDS    0x02
 #define CEPH_ENTITY_TYPE_OSD    0x04
 #define CEPH_ENTITY_TYPE_CLIENT 0x08
-#define CEPH_ENTITY_TYPE_ADMIN  0x10
 #define CEPH_ENTITY_TYPE_AUTH   0x20
 
 #define CEPH_ENTITY_TYPE_ANY    0xFF
diff --git a/fs/ceph/rados.h b/fs/ceph/rados.h
index fd56451..8fcc023 100644
--- a/fs/ceph/rados.h
+++ b/fs/ceph/rados.h
@@ -101,8 +101,8 @@
 	__le64 snap_seq;          /* seq for per-pool snapshot */
 	__le32 snap_epoch;        /* epoch of last snap */
 	__le32 num_snaps;
-	__le32 num_removed_snap_intervals;
-	__le64 uid;
+	__le32 num_removed_snap_intervals; /* if non-empty, NO per-pool snaps */
+	__le64 auid;               /* who owns the pg */
 } __attribute__ ((packed));
 
 /*
@@ -208,6 +208,7 @@
 	/* read */
 	CEPH_OSD_OP_GETXATTR  = CEPH_OSD_OP_MODE_RD | CEPH_OSD_OP_TYPE_ATTR | 1,
 	CEPH_OSD_OP_GETXATTRS = CEPH_OSD_OP_MODE_RD | CEPH_OSD_OP_TYPE_ATTR | 2,
+	CEPH_OSD_OP_CMPXATTR  = CEPH_OSD_OP_MODE_RD | CEPH_OSD_OP_TYPE_ATTR | 3,
 
 	/* write */
 	CEPH_OSD_OP_SETXATTR  = CEPH_OSD_OP_MODE_WR | CEPH_OSD_OP_TYPE_ATTR | 1,
@@ -305,6 +306,22 @@
 #define EOLDSNAPC    ERESTART  /* ORDERSNAP flag set; writer has old snapc*/
 #define EBLACKLISTED ESHUTDOWN /* blacklisted */
 
+/* xattr comparison */
+enum {
+	CEPH_OSD_CMPXATTR_OP_NOP = 0,
+	CEPH_OSD_CMPXATTR_OP_EQ  = 1,
+	CEPH_OSD_CMPXATTR_OP_NE  = 2,
+	CEPH_OSD_CMPXATTR_OP_GT  = 3,
+	CEPH_OSD_CMPXATTR_OP_GTE = 4,
+	CEPH_OSD_CMPXATTR_OP_LT  = 5,
+	CEPH_OSD_CMPXATTR_OP_LTE = 6
+};
+
+enum {
+	CEPH_OSD_CMPXATTR_MODE_STRING = 1,
+	CEPH_OSD_CMPXATTR_MODE_U64    = 2
+};
+
 /*
  * an individual object operation.  each may be accompanied by some data
  * payload
@@ -321,6 +338,8 @@
 		struct {
 			__le32 name_len;
 			__le32 value_len;
+			__u8 cmp_op;       /* CEPH_OSD_CMPXATTR_OP_* */
+			__u8 cmp_mode;     /* CEPH_OSD_CMPXATTR_MODE_* */
 		} __attribute__ ((packed)) xattr;
 		struct {
 			__u8 class_len;