From 8d82e0bbd78d06d9d781130c935f46c575bba0d8 Mon Sep 17 00:00:00 2001
From: Niels de Vos <ndevos@redhat.com>
Date: Mon, 27 Jan 2020 16:31:11 +0100
Subject: [PATCH] [DNM] dep: use wip/for-ceph-csi from nixpanic/go-ceph

---
 Gopkg.lock                                    |   6 +-
 Gopkg.toml                                    |   2 +-
 vendor/github.com/ceph/go-ceph/rados/conn.go  | 104 +++++------
 vendor/github.com/ceph/go-ceph/rados/ioctx.go | 142 ++++++++-------
 vendor/github.com/ceph/go-ceph/rados/rados.go |  17 +-
 .../github.com/ceph/go-ceph/rbd/features.go   |   4 +
 vendor/github.com/ceph/go-ceph/rbd/options.go |  47 +++++
 vendor/github.com/ceph/go-ceph/rbd/rbd.go     | 167 +++++++++++-------
 8 files changed, 300 insertions(+), 189 deletions(-)

diff --git a/Gopkg.lock b/Gopkg.lock
index cae2f9684a1e..a17d51f5bd38 100644
--- a/Gopkg.lock
+++ b/Gopkg.lock
@@ -26,8 +26,8 @@
   version = "v3.6.1"
 
 [[projects]]
-  branch = "wip/rbd/features"
-  digest = "1:06c11b0d54f55aa5423c0c8113f1f0d05cde9970324ab744fcb3cd052cf6340c"
+  branch = "wip/for-ceph-csi"
+  digest = "1:80515bd92a05744008890cbca9bec0ce9d3b3b09c068cf73c27af810e5728250"
   name = "github.com/ceph/go-ceph"
   packages = [
     "errutil",
@@ -35,7 +35,7 @@
     "rbd",
   ]
   pruneopts = "NUT"
-  revision = "e7569e5aaf34d4f7909c988fa5e6ef6450f19032"
+  revision = "468fed3b7316b89156bfe06192ceecaf4889e452"
   source = "github.com/nixpanic/go-ceph"
 
 [[projects]]
diff --git a/Gopkg.toml b/Gopkg.toml
index 3b53e4ccad7e..7cbfd166f034 100644
--- a/Gopkg.toml
+++ b/Gopkg.toml
@@ -76,7 +76,7 @@
   name = "k8s.io/utils"
 
 [[constraint]]
-  branch = "wip/rbd/features"
+  branch = "wip/for-ceph-csi"
   source = "github.com/nixpanic/go-ceph"
   name = "github.com/ceph/go-ceph"
 
diff --git a/vendor/github.com/ceph/go-ceph/rados/conn.go b/vendor/github.com/ceph/go-ceph/rados/conn.go
index ce76619787ab..0e1d09833157 100644
--- a/vendor/github.com/ceph/go-ceph/rados/conn.go
+++ b/vendor/github.com/ceph/go-ceph/rados/conn.go
@@ -12,6 +12,7 @@ import (
 )
 
 var (
+	// ErrNotConnected is returned when functions are called without a RADOS connection
 	ErrNotConnected = errors.New("RADOS not connected")
 )
 
@@ -43,9 +44,8 @@ func (c *Conn) PingMonitor(id string) (string, error) {
 	if ret == 0 {
 		reply := C.GoStringN(strout, (C.int)(strlen))
 		return reply, nil
-	} else {
-		return "", RadosError(int(ret))
 	}
+	return "", RadosError(int(ret))
 }
 
 // Connect establishes a connection to a RADOS cluster. It returns an error,
@@ -72,24 +72,21 @@ func (c *Conn) ReadConfigFile(path string) error {
 	c_path := C.CString(path)
 	defer C.free(unsafe.Pointer(c_path))
 	ret := C.rados_conf_read_file(c.cluster, c_path)
-	if ret == 0 {
-		return nil
-	} else {
-		return RadosError(int(ret))
-	}
+	return getRadosError(int(ret))
 }
 
 // ReadDefaultConfigFile configures the connection using a Ceph configuration
 // file located at default locations.
 func (c *Conn) ReadDefaultConfigFile() error {
 	ret := C.rados_conf_read_file(c.cluster, nil)
-	if ret == 0 {
-		return nil
-	} else {
-		return RadosError(int(ret))
-	}
+	return getRadosError(int(ret))
 }
 
+// OpenIOContext creates and returns a new IOContext for the given pool.
+//
+// Implements:
+//  int rados_ioctx_create(rados_t cluster, const char *pool_name,
+//                         rados_ioctx_t *ioctx);
 func (c *Conn) OpenIOContext(pool string) (*IOContext, error) {
 	c_pool := C.CString(pool)
 	defer C.free(unsafe.Pointer(c_pool))
@@ -97,9 +94,8 @@ func (c *Conn) OpenIOContext(pool string) (*IOContext, error) {
 	ret := C.rados_ioctx_create(c.cluster, c_pool, &ioctx.ioctx)
 	if ret == 0 {
 		return ioctx, nil
-	} else {
-		return nil, RadosError(int(ret))
 	}
+	return nil, RadosError(int(ret))
 }
 
 // ListPools returns the names of all existing pools.
@@ -136,11 +132,7 @@ func (c *Conn) SetConfigOption(option, value string) error {
 	defer C.free(unsafe.Pointer(c_opt))
 	defer C.free(unsafe.Pointer(c_val))
 	ret := C.rados_conf_set(c.cluster, c_opt, c_val)
-	if ret < 0 {
-		return RadosError(int(ret))
-	} else {
-		return nil
-	}
+	return getRadosError(int(ret))
 }
 
 // GetConfigOption returns the value of the Ceph configuration option
@@ -157,28 +149,22 @@ func (c *Conn) GetConfigOption(name string) (value string, err error) {
 	if ret == 0 {
 		value = C.GoString((*C.char)(unsafe.Pointer(&buf[0])))
 		return value, nil
-	} else {
-		return "", RadosError(ret)
 	}
+	return "", RadosError(ret)
 }
 
 // WaitForLatestOSDMap blocks the caller until the latest OSD map has been
 // retrieved.
 func (c *Conn) WaitForLatestOSDMap() error {
 	ret := C.rados_wait_for_latest_osdmap(c.cluster)
-	if ret < 0 {
-		return RadosError(int(ret))
-	} else {
-		return nil
-	}
+	return getRadosError(int(ret))
 }
 
 func (c *Conn) ensure_connected() error {
 	if c.connected {
 		return nil
-	} else {
-		return ErrNotConnected
 	}
+	return ErrNotConnected
 }
 
 // GetClusterStats returns statistics about the cluster associated with the
@@ -191,14 +177,13 @@ func (c *Conn) GetClusterStats() (stat ClusterStat, err error) {
 	ret := C.rados_cluster_stat(c.cluster, &c_stat)
 	if ret < 0 {
 		return ClusterStat{}, RadosError(int(ret))
-	} else {
-		return ClusterStat{
-			Kb:          uint64(c_stat.kb),
-			Kb_used:     uint64(c_stat.kb_used),
-			Kb_avail:    uint64(c_stat.kb_avail),
-			Num_objects: uint64(c_stat.num_objects),
-		}, nil
 	}
+	return ClusterStat{
+		Kb:          uint64(c_stat.kb),
+		Kb_used:     uint64(c_stat.kb_used),
+		Kb_avail:    uint64(c_stat.kb_avail),
+		Num_objects: uint64(c_stat.num_objects),
+	}, nil
 }
 
 // ParseCmdLineArgs configures the connection from command line arguments.
@@ -218,22 +203,14 @@ func (c *Conn) ParseCmdLineArgs(args []string) error {
 	}
 
 	ret := C.rados_conf_parse_argv(c.cluster, argc, &argv[0])
-	if ret < 0 {
-		return RadosError(int(ret))
-	} else {
-		return nil
-	}
+	return getRadosError(int(ret))
 }
 
 // ParseDefaultConfigEnv configures the connection from the default Ceph
 // environment variable(s).
 func (c *Conn) ParseDefaultConfigEnv() error {
 	ret := C.rados_conf_parse_env(c.cluster, nil)
-	if ret == 0 {
-		return nil
-	} else {
-		return RadosError(int(ret))
-	}
+	return getRadosError(int(ret))
 }
 
 // GetFSID returns the fsid of the cluster as a hexadecimal string. The fsid
@@ -246,9 +223,8 @@ func (c *Conn) GetFSID() (fsid string, err error) {
 	if ret == 36 {
 		fsid = C.GoString((*C.char)(unsafe.Pointer(&buf[0])))
 		return fsid, nil
-	} else {
-		return "", RadosError(int(ret))
 	}
+	return "", RadosError(int(ret))
 }
 
 // GetInstanceID returns a globally unique identifier for the cluster
@@ -263,11 +239,7 @@ func (c *Conn) MakePool(name string) error {
 	c_name := C.CString(name)
 	defer C.free(unsafe.Pointer(c_name))
 	ret := int(C.rados_pool_create(c.cluster, c_name))
-	if ret == 0 {
-		return nil
-	} else {
-		return RadosError(ret)
-	}
+	return getRadosError(int(ret))
 }
 
 // DeletePool deletes a pool and all the data inside the pool.
@@ -278,11 +250,7 @@ func (c *Conn) DeletePool(name string) error {
 	c_name := C.CString(name)
 	defer C.free(unsafe.Pointer(c_name))
 	ret := int(C.rados_pool_delete(c.cluster, c_name))
-	if ret == 0 {
-		return nil
-	} else {
-		return RadosError(ret)
-	}
+	return getRadosError(int(ret))
 }
 
 // GetPoolByName returns the ID of the pool with a given name.
@@ -295,9 +263,8 @@ func (c *Conn) GetPoolByName(name string) (int64, error) {
 	ret := int64(C.rados_pool_lookup(c.cluster, c_name))
 	if ret < 0 {
 		return 0, RadosError(ret)
-	} else {
-		return ret, nil
 	}
+	return ret, nil
 }
 
 // GetPoolByID returns the name of a pool by a given ID.
@@ -310,9 +277,8 @@ func (c *Conn) GetPoolByID(id int64) (string, error) {
 	ret := int(C.rados_pool_reverse_lookup(c.cluster, c_id, (*C.char)(unsafe.Pointer(&buf[0])), C.size_t(len(buf))))
 	if ret < 0 {
 		return "", RadosError(ret)
-	} else {
-		return C.GoString((*C.char)(unsafe.Pointer(&buf[0]))), nil
 	}
+	return C.GoString((*C.char)(unsafe.Pointer(&buf[0]))), nil
 }
 
 // MonCommand sends a command to one of the monitors
@@ -363,11 +329,25 @@ func (c *Conn) monCommand(args, inputBuffer []byte) (buffer []byte, info string,
 }
 
 // PGCommand sends a command to one of the PGs
+//
+// Implements:
+//  int rados_pg_command(rados_t cluster, const char *pgstr,
+//                       const char **cmd, size_t cmdlen,
+//                       const char *inbuf, size_t inbuflen,
+//                       char **outbuf, size_t *outbuflen,
+//                       char **outs, size_t *outslen);
 func (c *Conn) PGCommand(pgid []byte, args [][]byte) (buffer []byte, info string, err error) {
 	return c.pgCommand(pgid, args, nil)
 }
 
-// PGCommand sends a command to one of the PGs, with an input buffer
+// PGCommandWithInputBuffer sends a command to one of the PGs, with an input buffer
+//
+// Implements:
+//  int rados_pg_command(rados_t cluster, const char *pgstr,
+//                       const char **cmd, size_t cmdlen,
+//                       const char *inbuf, size_t inbuflen,
+//                       char **outbuf, size_t *outbuflen,
+//                       char **outs, size_t *outslen);
 func (c *Conn) PGCommandWithInputBuffer(pgid []byte, args [][]byte, inputBuffer []byte) (buffer []byte, info string, err error) {
 	return c.pgCommand(pgid, args, inputBuffer)
 }
diff --git a/vendor/github.com/ceph/go-ceph/rados/ioctx.go b/vendor/github.com/ceph/go-ceph/rados/ioctx.go
index 08eb835cd1c0..b9ef93194f5c 100644
--- a/vendor/github.com/ceph/go-ceph/rados/ioctx.go
+++ b/vendor/github.com/ceph/go-ceph/rados/ioctx.go
@@ -30,6 +30,13 @@ import (
 	"unsafe"
 )
 
+type RadosCreateOption int
+
+const (
+	RadosCreateExclusive  = C.LIBRADOS_CREATE_EXCLUSIVE
+	RadosCreateIdempotent = C.LIBRADOS_CREATE_IDEMPOTENT
+)
+
 // PoolStat represents Ceph pool statistics.
 type PoolStat struct {
 	// space used in bytes
@@ -93,6 +100,23 @@ func (ioctx *IOContext) SetNamespace(namespace string) {
 	C.rados_ioctx_set_namespace(ioctx.ioctx, c_ns)
 }
 
+// Create a new object with key oid.
+//
+// Implements:
+//  void rados_write_op_create(rados_write_op_t write_op, int exclusive,
+//                             const char* category)
+func (ioctx *IOContext) Create(oid string, exclusive RadosCreateOption) error {
+	c_oid := C.CString(oid)
+	defer C.free(unsafe.Pointer(c_oid))
+
+	op := C.rados_create_write_op()
+	C.rados_write_op_create(op, C.int(exclusive), nil)
+	ret := C.rados_write_op_operate(op, ioctx.ioctx, c_oid, nil, 0)
+	C.rados_release_write_op(op)
+
+	return getRadosError(int(ret))
+}
+
 // Write writes len(data) bytes to the object with key oid starting at byte
 // offset offset. It returns an error, if any.
 func (ioctx *IOContext) Write(oid string, data []byte, offset uint64) error {
@@ -109,7 +133,7 @@ func (ioctx *IOContext) Write(oid string, data []byte, offset uint64) error {
 		(C.size_t)(len(data)),
 		(C.uint64_t)(offset))
 
-	return GetRadosError(int(ret))
+	return getRadosError(int(ret))
 }
 
 // WriteFull writes len(data) bytes to the object with key oid.
@@ -122,7 +146,7 @@ func (ioctx *IOContext) WriteFull(oid string, data []byte) error {
 	ret := C.rados_write_full(ioctx.ioctx, c_oid,
 		(*C.char)(unsafe.Pointer(&data[0])),
 		(C.size_t)(len(data)))
-	return GetRadosError(int(ret))
+	return getRadosError(int(ret))
 }
 
 // Append appends len(data) bytes to the object with key oid.
@@ -135,7 +159,7 @@ func (ioctx *IOContext) Append(oid string, data []byte) error {
 	ret := C.rados_append(ioctx.ioctx, c_oid,
 		(*C.char)(unsafe.Pointer(&data[0])),
 		(C.size_t)(len(data)))
-	return GetRadosError(int(ret))
+	return getRadosError(int(ret))
 }
 
 // Read reads up to len(data) bytes from the object with key oid starting at byte
@@ -158,9 +182,8 @@ func (ioctx *IOContext) Read(oid string, data []byte, offset uint64) (int, error
 
 	if ret >= 0 {
 		return int(ret), nil
-	} else {
-		return 0, GetRadosError(int(ret))
 	}
+	return 0, getRadosError(int(ret))
 }
 
 // Delete deletes the object with key oid. It returns an error, if any.
@@ -168,7 +191,7 @@ func (ioctx *IOContext) Delete(oid string) error {
 	c_oid := C.CString(oid)
 	defer C.free(unsafe.Pointer(c_oid))
 
-	return GetRadosError(int(C.rados_remove(ioctx.ioctx, c_oid)))
+	return getRadosError(int(C.rados_remove(ioctx.ioctx, c_oid)))
 }
 
 // Truncate resizes the object with key oid to size size. If the operation
@@ -179,7 +202,7 @@ func (ioctx *IOContext) Truncate(oid string, size uint64) error {
 	c_oid := C.CString(oid)
 	defer C.free(unsafe.Pointer(c_oid))
 
-	return GetRadosError(int(C.rados_trunc(ioctx.ioctx, c_oid, (C.uint64_t)(size))))
+	return getRadosError(int(C.rados_trunc(ioctx.ioctx, c_oid, (C.uint64_t)(size))))
 }
 
 // Destroy informs librados that the I/O context is no longer in use.
@@ -189,29 +212,32 @@ func (ioctx *IOContext) Destroy() {
 	C.rados_ioctx_destroy(ioctx.ioctx)
 }
 
-// Stat returns a set of statistics about the pool associated with this I/O
+// GetPoolStats returns a set of statistics about the pool associated with this I/O
 // context.
+//
+// Implements:
+//  int rados_ioctx_pool_stat(rados_ioctx_t io,
+//                            struct rados_pool_stat_t *stats);
 func (ioctx *IOContext) GetPoolStats() (stat PoolStat, err error) {
 	c_stat := C.struct_rados_pool_stat_t{}
 	ret := C.rados_ioctx_pool_stat(ioctx.ioctx, &c_stat)
 	if ret < 0 {
-		return PoolStat{}, GetRadosError(int(ret))
-	} else {
-		return PoolStat{
-			Num_bytes:                      uint64(c_stat.num_bytes),
-			Num_kb:                         uint64(c_stat.num_kb),
-			Num_objects:                    uint64(c_stat.num_objects),
-			Num_object_clones:              uint64(c_stat.num_object_clones),
-			Num_object_copies:              uint64(c_stat.num_object_copies),
-			Num_objects_missing_on_primary: uint64(c_stat.num_objects_missing_on_primary),
-			Num_objects_unfound:            uint64(c_stat.num_objects_unfound),
-			Num_objects_degraded:           uint64(c_stat.num_objects_degraded),
-			Num_rd:                         uint64(c_stat.num_rd),
-			Num_rd_kb:                      uint64(c_stat.num_rd_kb),
-			Num_wr:                         uint64(c_stat.num_wr),
-			Num_wr_kb:                      uint64(c_stat.num_wr_kb),
-		}, nil
-	}
+		return PoolStat{}, getRadosError(int(ret))
+	}
+	return PoolStat{
+		Num_bytes:                      uint64(c_stat.num_bytes),
+		Num_kb:                         uint64(c_stat.num_kb),
+		Num_objects:                    uint64(c_stat.num_objects),
+		Num_object_clones:              uint64(c_stat.num_object_clones),
+		Num_object_copies:              uint64(c_stat.num_object_copies),
+		Num_objects_missing_on_primary: uint64(c_stat.num_objects_missing_on_primary),
+		Num_objects_unfound:            uint64(c_stat.num_objects_unfound),
+		Num_objects_degraded:           uint64(c_stat.num_objects_degraded),
+		Num_rd:                         uint64(c_stat.num_rd),
+		Num_rd_kb:                      uint64(c_stat.num_rd_kb),
+		Num_wr:                         uint64(c_stat.num_wr),
+		Num_wr_kb:                      uint64(c_stat.num_wr_kb),
+	}, nil
 }
 
 // GetPoolName returns the name of the pool associated with the I/O context.
@@ -224,7 +250,7 @@ func (ioctx *IOContext) GetPoolName() (name string, err error) {
 			buf = make([]byte, len(buf)*2)
 			continue
 		} else if ret < 0 {
-			return "", GetRadosError(int(ret))
+			return "", getRadosError(int(ret))
 		}
 		name = C.GoStringN((*C.char)(unsafe.Pointer(&buf[0])), ret)
 		return name, nil
@@ -244,7 +270,7 @@ func (ioctx *IOContext) ListObjects(listFn ObjectListFunc) error {
 	var ctx C.rados_list_ctx_t
 	ret := C.rados_nobjects_list_open(ioctx.ioctx, &ctx)
 	if ret < 0 {
-		return GetRadosError(int(ret))
+		return getRadosError(int(ret))
 	}
 	defer func() { C.rados_nobjects_list_close(ctx) }()
 
@@ -254,7 +280,7 @@ func (ioctx *IOContext) ListObjects(listFn ObjectListFunc) error {
 		if ret == -C.ENOENT {
 			return nil
 		} else if ret < 0 {
-			return GetRadosError(int(ret))
+			return getRadosError(int(ret))
 		}
 		listFn(C.GoString(c_entry))
 	}
@@ -274,13 +300,12 @@ func (ioctx *IOContext) Stat(object string) (stat ObjectStat, err error) {
 		&c_pmtime)
 
 	if ret < 0 {
-		return ObjectStat{}, GetRadosError(int(ret))
-	} else {
-		return ObjectStat{
-			Size:    uint64(c_psize),
-			ModTime: time.Unix(int64(c_pmtime), 0),
-		}, nil
+		return ObjectStat{}, getRadosError(int(ret))
 	}
+	return ObjectStat{
+		Size:    uint64(c_psize),
+		ModTime: time.Unix(int64(c_pmtime), 0),
+	}, nil
 }
 
 // GetXattr gets an xattr with key `name`, it returns the length of
@@ -300,12 +325,11 @@ func (ioctx *IOContext) GetXattr(object string, name string, data []byte) (int,
 
 	if ret >= 0 {
 		return int(ret), nil
-	} else {
-		return 0, GetRadosError(int(ret))
 	}
+	return 0, getRadosError(int(ret))
 }
 
-// Sets an xattr for an object with key `name` with value as `data`
+// SetXattr sets an xattr for an object with key `name` with value as `data`
 func (ioctx *IOContext) SetXattr(object string, name string, data []byte) error {
 	c_object := C.CString(object)
 	c_name := C.CString(name)
@@ -319,12 +343,11 @@ func (ioctx *IOContext) SetXattr(object string, name string, data []byte) error
 		(*C.char)(unsafe.Pointer(&data[0])),
 		(C.size_t)(len(data)))
 
-	return GetRadosError(int(ret))
+	return getRadosError(int(ret))
 }
 
-// function that lists all the xattrs for an object, since xattrs are
-// a k-v pair, this function returns a map of k-v pairs on
-// success, error code on failure
+// ListXattrs lists all the xattrs for an object. The xattrs are returned as a
+// mapping of string keys and byte-slice values.
 func (ioctx *IOContext) ListXattrs(oid string) (map[string][]byte, error) {
 	c_oid := C.CString(oid)
 	defer C.free(unsafe.Pointer(c_oid))
@@ -333,7 +356,7 @@ func (ioctx *IOContext) ListXattrs(oid string) (map[string][]byte, error) {
 
 	ret := C.rados_getxattrs(ioctx.ioctx, c_oid, &it)
 	if ret < 0 {
-		return nil, GetRadosError(int(ret))
+		return nil, getRadosError(int(ret))
 	}
 	defer func() { C.rados_getxattrs_end(it) }()
 	m := make(map[string][]byte)
@@ -345,7 +368,7 @@ func (ioctx *IOContext) ListXattrs(oid string) (map[string][]byte, error) {
 
 		ret := C.rados_getxattrs_next(it, &c_name, &c_val, &c_len)
 		if ret < 0 {
-			return nil, GetRadosError(int(ret))
+			return nil, getRadosError(int(ret))
 		}
 		// rados api returns a null name,val & 0-length upon
 		// end of iteration
@@ -368,10 +391,10 @@ func (ioctx *IOContext) RmXattr(oid string, name string) error {
 		c_oid,
 		c_name)
 
-	return GetRadosError(int(ret))
+	return getRadosError(int(ret))
 }
 
-// Append the map `pairs` to the omap `oid`
+// SetOmap appends the map `pairs` to the omap `oid`
 func (ioctx *IOContext) SetOmap(oid string, pairs map[string][]byte) error {
 	c_oid := C.CString(oid)
 	defer C.free(unsafe.Pointer(c_oid))
@@ -424,7 +447,7 @@ func (ioctx *IOContext) SetOmap(oid string, pairs map[string][]byte) error {
 	ret := C.rados_write_op_operate(op, ioctx.ioctx, c_oid, nil, 0)
 	C.rados_release_write_op(op)
 
-	return GetRadosError(int(ret))
+	return getRadosError(int(ret))
 }
 
 // OmapListFunc is the type of the function called for each omap key
@@ -463,7 +486,7 @@ func (ioctx *IOContext) ListOmapValues(oid string, startAfter string, filterPref
 	ret := C.rados_read_op_operate(op, ioctx.ioctx, c_oid, 0)
 
 	if int(ret) != 0 {
-		return GetRadosError(int(ret))
+		return getRadosError(int(ret))
 	} else if int(c_prval) != 0 {
 		return RadosError(int(c_prval))
 	}
@@ -476,7 +499,7 @@ func (ioctx *IOContext) ListOmapValues(oid string, startAfter string, filterPref
 		ret = C.rados_omap_get_next(c_iter, &c_key, &c_val, &c_len)
 
 		if int(ret) != 0 {
-			return GetRadosError(int(ret))
+			return getRadosError(int(ret))
 		}
 
 		if c_key == nil {
@@ -569,7 +592,7 @@ func (ioctx *IOContext) RmOmapKeys(oid string, keys []string) error {
 	ret := C.rados_write_op_operate(op, ioctx.ioctx, c_oid, nil, 0)
 	C.rados_release_write_op(op)
 
-	return GetRadosError(int(ret))
+	return getRadosError(int(ret))
 }
 
 // CleanOmap clears the omap `oid`
@@ -583,7 +606,7 @@ func (ioctx *IOContext) CleanOmap(oid string) error {
 	ret := C.rados_write_op_operate(op, ioctx.ioctx, c_oid, nil, 0)
 	C.rados_release_write_op(op)
 
-	return GetRadosError(int(ret))
+	return getRadosError(int(ret))
 }
 
 type Iter struct {
@@ -599,7 +622,7 @@ type IterToken uint32
 func (ioctx *IOContext) Iter() (*Iter, error) {
 	iter := Iter{}
 	if cerr := C.rados_nobjects_list_open(ioctx.ioctx, &iter.ctx); cerr < 0 {
-		return nil, GetRadosError(int(cerr))
+		return nil, getRadosError(int(cerr))
 	}
 	return &iter, nil
 }
@@ -631,7 +654,7 @@ func (iter *Iter) Next() bool {
 	var c_entry *C.char
 	var c_namespace *C.char
 	if cerr := C.rados_nobjects_list_next(iter.ctx, &c_entry, nil, &c_namespace); cerr < 0 {
-		iter.err = GetRadosError(int(cerr))
+		iter.err = getRadosError(int(cerr))
 		return false
 	}
 	iter.entry = C.GoString(c_entry)
@@ -768,7 +791,7 @@ func (ioctx *IOContext) LockShared(oid, name, cookie, tag, desc string, duration
 	}
 }
 
-// Release a shared or exclusive lock on an object.
+// Unlock releases a shared or exclusive lock on an object.
 func (ioctx *IOContext) Unlock(oid, name, cookie string) (int, error) {
 	c_oid := C.CString(oid)
 	c_name := C.CString(name)
@@ -797,9 +820,11 @@ func (ioctx *IOContext) Unlock(oid, name, cookie string) (int, error) {
 	}
 }
 
-// List clients that have locked the named object lock and information about the lock.
-// The number of bytes required in each buffer is put in the corresponding size out parameter.
-// If any of the provided buffers are too short, -ERANGE is returned after these sizes are filled in.
+// ListLockers lists clients that have locked the named object lock and
+// information about the lock.
+// The number of bytes required in each buffer is put in the corresponding size
+// out parameter.  If any of the provided buffers are too short, -ERANGE is
+// returned after these sizes are filled in.
 func (ioctx *IOContext) ListLockers(oid, name string) (*LockInfo, error) {
 	c_oid := C.CString(oid)
 	c_name := C.CString(name)
@@ -849,12 +874,11 @@ func (ioctx *IOContext) ListLockers(oid, name string) (*LockInfo, error) {
 
 	if ret < 0 {
 		return nil, RadosError(int(ret))
-	} else {
-		return &LockInfo{int(ret), c_exclusive == 1, C.GoString(c_tag), splitCString(c_clients, c_clients_len), splitCString(c_cookies, c_cookies_len), splitCString(c_addrs, c_addrs_len)}, nil
 	}
+	return &LockInfo{int(ret), c_exclusive == 1, C.GoString(c_tag), splitCString(c_clients, c_clients_len), splitCString(c_cookies, c_cookies_len), splitCString(c_addrs, c_addrs_len)}, nil
 }
 
-// Releases a shared or exclusive lock on an object, which was taken by the specified client.
+// BreakLock releases a shared or exclusive lock on an object, which was taken by the specified client.
 func (ioctx *IOContext) BreakLock(oid, name, client, cookie string) (int, error) {
 	c_oid := C.CString(oid)
 	c_name := C.CString(name)
diff --git a/vendor/github.com/ceph/go-ceph/rados/rados.go b/vendor/github.com/ceph/go-ceph/rados/rados.go
index 22714c2a5d95..18b382d3cc26 100644
--- a/vendor/github.com/ceph/go-ceph/rados/rados.go
+++ b/vendor/github.com/ceph/go-ceph/rados/rados.go
@@ -14,8 +14,10 @@ import (
 	"github.com/ceph/go-ceph/errutil"
 )
 
+// RadosError represents an error condition returned from the Ceph RADOS APIs.
 type RadosError int
 
+// Error returns the error string for the RadosError type.
 func (e RadosError) Error() string {
 	errno, s := errutil.FormatErrno(int(e))
 	if s == "" {
@@ -24,12 +26,19 @@ func (e RadosError) Error() string {
 	return fmt.Sprintf("rados: ret=%d, %s", errno, s)
 }
 
-var RadosAllNamespaces = C.LIBRADOS_ALL_NSPACES
+var (
+	// RadosAllNamespaces is used to reset a selected namespace to all namespaces. See the IOContext SetNamespace function.
+	RadosAllNamespaces = C.LIBRADOS_ALL_NSPACES
 
-var RadosErrorNotFound = RadosError(-C.ENOENT)
-var RadosErrorPermissionDenied = RadosError(-C.EPERM)
+	// RadosErrorNotFound indicates a missing resource.
+	RadosErrorNotFound = RadosError(-C.ENOENT)
+	// RadosErrorPermissionDenied indicates a permissions issue.
+	RadosErrorPermissionDenied = RadosError(-C.EPERM)
+	// RadosErrorObjectExists indicates that an exclusive object creation failed.
+	RadosErrorObjectExist = RadosError(-C.EEXIST)
+)
 
-func GetRadosError(err int) error {
+func getRadosError(err int) error {
 	if err == 0 {
 		return nil
 	}
diff --git a/vendor/github.com/ceph/go-ceph/rbd/features.go b/vendor/github.com/ceph/go-ceph/rbd/features.go
index 58ab08371b3b..ecffc73dd49b 100644
--- a/vendor/github.com/ceph/go-ceph/rbd/features.go
+++ b/vendor/github.com/ceph/go-ceph/rbd/features.go
@@ -114,6 +114,10 @@ func GetFeatureByName(name string) *Feature {
 	return nil
 }
 
+// GetFeatures returns the features bitmask for the rbd image.
+//
+// Implements:
+//  int rbd_get_features(rbd_image_t image, uint64_t *features);
 func (image *Image) GetFeatures() (features uint64, err error) {
 	if err := image.validate(imageIsOpen); err != nil {
 		return 0, err
diff --git a/vendor/github.com/ceph/go-ceph/rbd/options.go b/vendor/github.com/ceph/go-ceph/rbd/options.go
index b5aa17944396..696b04ec6b1f 100644
--- a/vendor/github.com/ceph/go-ceph/rbd/options.go
+++ b/vendor/github.com/ceph/go-ceph/rbd/options.go
@@ -33,16 +33,30 @@ type RbdImageOptions struct {
 
 type RbdImageOption C.int
 
+// NewRbdImageOptions creates a new RbdImageOptions struct. Call
+// RbdImageOptions.Destroy() to free the resources.
+//
+// Implements:
+//  void rbd_image_options_create(rbd_image_options_t* opts)
 func NewRbdImageOptions() *RbdImageOptions {
 	rio := &RbdImageOptions{}
 	C.rbd_image_options_create(&rio.options)
 	return rio
 }
 
+// Destroy a RbdImageOptions struct and free the associated resources.
+//
+// Implements:
+//  void rbd_image_options_destroy(rbd_image_options_t opts);
 func (rio *RbdImageOptions) Destroy() {
 	C.rbd_image_options_destroy(rio.options)
 }
 
+// SetString sets the value of the RbdImageOption to the given string.
+//
+// Implements:
+//  int rbd_image_options_set_string(rbd_image_options_t opts, int optname,
+//          const char* optval);
 func (rio *RbdImageOptions) SetString(option RbdImageOption, value string) error {
 	c_value := C.CString(value)
 	defer C.free(unsafe.Pointer(c_value))
@@ -56,6 +70,11 @@ func (rio *RbdImageOptions) SetString(option RbdImageOption, value string) error
 	return nil
 }
 
+// GetString returns the string value of the RbdImageOption.
+//
+// Implements:
+//  int rbd_image_options_get_string(rbd_image_options_t opts, int optname,
+//          char* optval, size_t maxlen);
 func (rio *RbdImageOptions) GetString(option RbdImageOption) (string, error) {
 	value := make([]byte, 4096)
 
@@ -69,6 +88,11 @@ func (rio *RbdImageOptions) GetString(option RbdImageOption) (string, error) {
 	return C.GoString((*C.char)(unsafe.Pointer(&value[0]))), nil
 }
 
+// SetUint64 sets the value of the RbdImageOption to the given uint64.
+//
+// Implements:
+//  int rbd_image_options_set_uint64(rbd_image_options_t opts, int optname,
+//          const uint64_t optval);
 func (rio *RbdImageOptions) SetUint64(option RbdImageOption, value uint64) error {
 	c_value := C.uint64_t(value)
 
@@ -81,6 +105,11 @@ func (rio *RbdImageOptions) SetUint64(option RbdImageOption, value uint64) error
 	return nil
 }
 
+// GetUint64 returns the uint64 value of the RbdImageOption.
+//
+// Implements:
+//  int rbd_image_options_get_uint64(rbd_image_options_t opts, int optname,
+//          uint64_t* optval);
 func (rio *RbdImageOptions) GetUint64(option RbdImageOption) (uint64, error) {
 	var c_value C.uint64_t
 
@@ -92,6 +121,11 @@ func (rio *RbdImageOptions) GetUint64(option RbdImageOption) (uint64, error) {
 	return uint64(c_value), nil
 }
 
+// IsSet returns a true if the RbdImageOption is set, false otherwise.
+//
+// Implements:
+//  int rbd_image_options_is_set(rbd_image_options_t opts, int optname,
+//          bool* is_set);
 func (rio *RbdImageOptions) IsSet(option RbdImageOption) (bool, error) {
 	var c_set C.bool
 
@@ -103,6 +137,10 @@ func (rio *RbdImageOptions) IsSet(option RbdImageOption) (bool, error) {
 	return bool(c_set), nil
 }
 
+// Unset a given RbdImageOption.
+//
+// Implements:
+//  int rbd_image_options_unset(rbd_image_options_t opts, int optname)
 func (rio *RbdImageOptions) Unset(option RbdImageOption) error {
 	ret := C.rbd_image_options_unset(rio.options, C.int(option))
 	if ret != 0 {
@@ -112,10 +150,19 @@ func (rio *RbdImageOptions) Unset(option RbdImageOption) error {
 	return nil
 }
 
+// Clear all options in the RbdImageOptions.
+//
+// Implements:
+//  void rbd_image_options_clear(rbd_image_options_t opts)
 func (rio *RbdImageOptions) Clear() {
 	C.rbd_image_options_clear(rio.options)
 }
 
+// IsEmpty returns true if there are no options set in the RbdImageOptions,
+// false otherwise.
+//
+// Implements:
+//  int rbd_image_options_is_empty(rbd_image_options_t opts)
 func (rio *RbdImageOptions) IsEmpty() bool {
 	ret := C.rbd_image_options_is_empty(rio.options)
 	return ret != 0
diff --git a/vendor/github.com/ceph/go-ceph/rbd/rbd.go b/vendor/github.com/ceph/go-ceph/rbd/rbd.go
index 149673f003c7..2ec930297bd1 100644
--- a/vendor/github.com/ceph/go-ceph/rbd/rbd.go
+++ b/vendor/github.com/ceph/go-ceph/rbd/rbd.go
@@ -168,7 +168,7 @@ func GetError(err C.int) error {
 	}
 }
 
-//
+// Version returns the major, minor, and patch level of the librbd library.
 func Version() (int, int, int) {
 	var c_major, c_minor, c_patch C.int
 	C.rbd_version(&c_major, &c_minor, &c_patch)
@@ -199,7 +199,7 @@ func GetImageNames(ioctx *rados.IOContext) (names []string, err error) {
 	}
 }
 
-//
+// GetImage gets a reference to a previously created rbd image.
 func GetImage(ioctx *rados.IOContext, name string) *Image {
 	return &Image{
 		ioctx: ioctx,
@@ -207,12 +207,15 @@ func GetImage(ioctx *rados.IOContext, name string) *Image {
 	}
 }
 
-// int rbd_create(rados_ioctx_t io, const char *name, uint64_t size, int *order);
+// Create a new rbd image.
+//
+// Implements:
+//  int rbd_create(rados_ioctx_t io, const char *name, uint64_t size, int *order);
 //
-// But also (for backward compability):
-// int rbd_create2(rados_ioctx_t io, const char *name, uint64_t size,
+// Also implements (for backward compatibility):
+//  int rbd_create2(rados_ioctx_t io, const char *name, uint64_t size,
 //          uint64_t features, int *order);
-// int rbd_create3(rados_ioctx_t io, const char *name, uint64_t size,
+//  int rbd_create3(rados_ioctx_t io, const char *name, uint64_t size,
 //        uint64_t features, int *order,
 //        uint64_t stripe_unit, uint64_t stripe_count);
 func Create(ioctx *rados.IOContext, name string, size uint64, order int,
@@ -247,7 +250,10 @@ func Create(ioctx *rados.IOContext, name string, size uint64, order int,
 	}, nil
 }
 
-// int rbd_create2(rados_ioctx_t io, const char *name, uint64_t size,
+// Create2 creates a new rbd image using provided features.
+//
+// Implements:
+//  int rbd_create2(rados_ioctx_t io, const char *name, uint64_t size,
 //          uint64_t features, int *order);
 func Create2(ioctx *rados.IOContext, name string, size uint64, features uint64,
 	order int) (image *Image, err error) {
@@ -270,7 +276,11 @@ func Create2(ioctx *rados.IOContext, name string, size uint64, features uint64,
 	}, nil
 }
 
-// int rbd_create3(rados_ioctx_t io, const char *name, uint64_t size,
+// Create3 creates a new rbd image using provided features and stripe
+// parameters.
+//
+// Implements:
+//  int rbd_create3(rados_ioctx_t io, const char *name, uint64_t size,
 //        uint64_t features, int *order,
 //        uint64_t stripe_unit, uint64_t stripe_count);
 func Create3(ioctx *rados.IOContext, name string, size uint64, features uint64,
@@ -295,7 +305,10 @@ func Create3(ioctx *rados.IOContext, name string, size uint64, features uint64,
 	}, nil
 }
 
-// int rbd_create4(rados_ioctx_t io, const char *name, uint64_t size,
+// Create4 creates a new rbd image using provided image options.
+//
+// Implements:
+//  int rbd_create4(rados_ioctx_t io, const char *name, uint64_t size,
 //                 rbd_image_options_t opts);
 func Create4(ioctx *rados.IOContext, name string, size uint64, rio *RbdImageOptions) (image *Image, err error) {
 	if rio == nil {
@@ -318,34 +331,12 @@ func Create4(ioctx *rados.IOContext, name string, size uint64, rio *RbdImageOpti
 	}, nil
 }
 
-func CreateWithOptions(ioctx *rados.IOContext, name string, size uint64, rio *RbdImageOptions) (image *Image, err error) {
-	if rio == nil {
-		return nil, RBDError(C.EINVAL)
-	}
-
-	c_name := C.CString(name)
-	defer C.free(unsafe.Pointer(c_name))
-
-	ret := C.rbd_create4(C.rados_ioctx_t(ioctx.Pointer()), c_name,
-		C.uint64_t(size), C.rbd_image_options_t(rio.options))
-
-	if ret < 0 {
-		return nil, RBDError(ret)
-	}
-
-	return &Image{
-		ioctx: ioctx,
-		name:  name,
-	}, nil
-}
-
-// int rbd_clone(rados_ioctx_t p_ioctx, const char *p_name,
+// Clone a new rbd image from a snapshot.
+//
+// Implements:
+//  int rbd_clone(rados_ioctx_t p_ioctx, const char *p_name,
 //           const char *p_snapname, rados_ioctx_t c_ioctx,
 //           const char *c_name, uint64_t features, int *c_order);
-// int rbd_clone2(rados_ioctx_t p_ioctx, const char *p_name,
-//            const char *p_snapname, rados_ioctx_t c_ioctx,
-//            const char *c_name, uint64_t features, int *c_order,
-//            uint64_t stripe_unit, int stripe_count);
 func (image *Image) Clone(snapname string, c_ioctx *rados.IOContext, c_name string, features uint64, order int) (*Image, error) {
 	if err := image.validate(imageNeedsIOContext); err != nil {
 		return nil, err
@@ -374,9 +365,10 @@ func (image *Image) Clone(snapname string, c_ioctx *rados.IOContext, c_name stri
 	}, nil
 }
 
-// int rbd_remove(rados_ioctx_t io, const char *name);
-// int rbd_remove_with_progress(rados_ioctx_t io, const char *name,
-//                  librbd_progress_fn_t cb, void *cbdata);
+// Remove the specified rbd image.
+//
+// Implements:
+//  int rbd_remove(rados_ioctx_t io, const char *name);
 func (image *Image) Remove() error {
 	if err := image.validate(imageNeedsIOContext | imageNeedsName); err != nil {
 		return err
@@ -401,7 +393,10 @@ func (image *Image) Trash(delay time.Duration) error {
 		C.uint64_t(delay.Seconds())))
 }
 
-// int rbd_rename(rados_ioctx_t src_io_ctx, const char *srcname, const char *destname);
+// Rename an rbd image.
+//
+// Implements:
+//  int rbd_rename(rados_ioctx_t src_io_ctx, const char *srcname, const char *destname);
 func (image *Image) Rename(destname string) error {
 	if err := image.validate(imageNeedsIOContext | imageNeedsName); err != nil {
 		return err
@@ -465,7 +460,10 @@ func (image *Image) Open(args ...interface{}) error {
 	return GetError(ret)
 }
 
-// int rbd_close(rbd_image_t image);
+// Close an open rbd image.
+//
+// Implements:
+//  int rbd_close(rbd_image_t image);
 func (image *Image) Close() error {
 	if err := image.validate(imageIsOpen); err != nil {
 		return err
@@ -479,7 +477,10 @@ func (image *Image) Close() error {
 	return nil
 }
 
-// int rbd_resize(rbd_image_t image, uint64_t size);
+// Resize an rbd image.
+//
+// Implements:
+//  int rbd_resize(rbd_image_t image, uint64_t size);
 func (image *Image) Resize(size uint64) error {
 	if err := image.validate(imageIsOpen); err != nil {
 		return err
@@ -488,7 +489,10 @@ func (image *Image) Resize(size uint64) error {
 	return GetError(C.rbd_resize(image.image, C.uint64_t(size)))
 }
 
-// int rbd_stat(rbd_image_t image, rbd_image_info_t *info, size_t infosize);
+// Stat an rbd image.
+//
+// Implements:
+//  int rbd_stat(rbd_image_t image, rbd_image_info_t *info, size_t infosize);
 func (image *Image) Stat() (info *ImageInfo, err error) {
 	if err := image.validate(imageIsOpen); err != nil {
 		return nil, err
@@ -510,7 +514,10 @@ func (image *Image) Stat() (info *ImageInfo, err error) {
 		Parent_name:       C.GoString((*C.char)(&c_stat.parent_name[0]))}, nil
 }
 
-// int rbd_get_old_format(rbd_image_t image, uint8_t *old);
+// IsOldFormat returns true if the rbd image uses the old format.
+//
+// Implements:
+//  int rbd_get_old_format(rbd_image_t image, uint8_t *old);
 func (image *Image) IsOldFormat() (old_format bool, err error) {
 	if err := image.validate(imageIsOpen); err != nil {
 		return false, err
@@ -526,7 +533,10 @@ func (image *Image) IsOldFormat() (old_format bool, err error) {
 	return c_old_format != 0, nil
 }
 
-// int rbd_size(rbd_image_t image, uint64_t *size);
+// GetSize returns the size of the rbd image.
+//
+// Implements:
+//  int rbd_size(rbd_image_t image, uint64_t *size);
 func (image *Image) GetSize() (size uint64, err error) {
 	if err := image.validate(imageIsOpen); err != nil {
 		return 0, err
@@ -539,7 +549,10 @@ func (image *Image) GetSize() (size uint64, err error) {
 	return size, nil
 }
 
-// int rbd_get_stripe_unit(rbd_image_t image, uint64_t *stripe_unit);
+// GetStripeUnit returns the stripe-unit value for the rbd image.
+//
+// Implements:
+//  int rbd_get_stripe_unit(rbd_image_t image, uint64_t *stripe_unit);
 func (image *Image) GetStripeUnit() (stripe_unit uint64, err error) {
 	if err := image.validate(imageIsOpen); err != nil {
 		return 0, err
@@ -552,7 +565,10 @@ func (image *Image) GetStripeUnit() (stripe_unit uint64, err error) {
 	return stripe_unit, nil
 }
 
-// int rbd_get_stripe_count(rbd_image_t image, uint64_t *stripe_count);
+// GetStripeCount returns the stripe-count value for the rbd image.
+//
+// Implements:
+//  int rbd_get_stripe_count(rbd_image_t image, uint64_t *stripe_count);
 func (image *Image) GetStripeCount() (stripe_count uint64, err error) {
 	if err := image.validate(imageIsOpen); err != nil {
 		return 0, err
@@ -565,7 +581,11 @@ func (image *Image) GetStripeCount() (stripe_count uint64, err error) {
 	return stripe_count, nil
 }
 
-// int rbd_get_overlap(rbd_image_t image, uint64_t *overlap);
+// GetOverlap returns the overlapping bytes between the rbd image and its
+// parent.
+//
+// Implements:
+//  int rbd_get_overlap(rbd_image_t image, uint64_t *overlap);
 func (image *Image) GetOverlap() (overlap uint64, err error) {
 	if err := image.validate(imageIsOpen); err != nil {
 		return 0, err
@@ -578,7 +598,10 @@ func (image *Image) GetOverlap() (overlap uint64, err error) {
 	return overlap, nil
 }
 
-// int rbd_copy(rbd_image_t image, rados_ioctx_t dest_io_ctx, const char *destname);
+// Copy one rbd image to another.
+//
+// Implements:
+//  int rbd_copy(rbd_image_t image, rados_ioctx_t dest_io_ctx, const char *destname);
 func (image *Image) Copy(ioctx *rados.IOContext, destname string) error {
 	if err := image.validate(imageIsOpen); err != nil {
 		return err
@@ -595,7 +618,10 @@ func (image *Image) Copy(ioctx *rados.IOContext, destname string) error {
 		C.rados_ioctx_t(ioctx.Pointer()), c_destname))
 }
 
-// int rbd_copy2(rbd_image_t src, rbd_image_t dest);
+// Copy one rbd image to another, using an image handle.
+//
+// Implements:
+//  int rbd_copy2(rbd_image_t src, rbd_image_t dest);
 func (image *Image) Copy2(dest *Image) error {
 	if err := image.validate(imageIsOpen); err != nil {
 		return err
@@ -606,7 +632,10 @@ func (image *Image) Copy2(dest *Image) error {
 	return GetError(C.rbd_copy2(image.image, dest.image))
 }
 
-// int rbd_flatten(rbd_image_t image);
+// Flatten removes snapshot references from the image.
+//
+// Implements:
+//  int rbd_flatten(rbd_image_t image);
 func (image *Image) Flatten() error {
 	if err := image.validate(imageIsOpen); err != nil {
 		return err
@@ -615,7 +644,10 @@ func (image *Image) Flatten() error {
 	return GetError(C.rbd_flatten(image.image))
 }
 
-// ssize_t rbd_list_children(rbd_image_t image, char *pools, size_t *pools_len,
+// ListChildren returns a list of images that reference the current snapshot.
+//
+// Implements:
+//  ssize_t rbd_list_children(rbd_image_t image, char *pools, size_t *pools_len,
 //               char *images, size_t *images_len);
 func (image *Image) ListChildren() (pools []string, images []string, err error) {
 	if err := image.validate(imageIsOpen); err != nil {
@@ -665,7 +697,10 @@ func (image *Image) ListChildren() (pools []string, images []string, err error)
 	return pools, images, nil
 }
 
-// ssize_t rbd_list_lockers(rbd_image_t image, int *exclusive,
+// ListLockers returns a list of clients that have locks on the image.
+//
+// Impelemnts:
+//  ssize_t rbd_list_lockers(rbd_image_t image, int *exclusive,
 //              char *tag, size_t *tag_len,
 //              char *clients, size_t *clients_len,
 //              char *cookies, size_t *cookies_len,
@@ -726,7 +761,10 @@ func (image *Image) ListLockers() (tag string, lockers []Locker, err error) {
 	return string(tag_buf), lockers, nil
 }
 
-// int rbd_lock_exclusive(rbd_image_t image, const char *cookie);
+// LockExclusive acquires an exclusive lock on the rbd image.
+//
+// Implements:
+//  int rbd_lock_exclusive(rbd_image_t image, const char *cookie);
 func (image *Image) LockExclusive(cookie string) error {
 	if err := image.validate(imageIsOpen); err != nil {
 		return err
@@ -738,7 +776,10 @@ func (image *Image) LockExclusive(cookie string) error {
 	return GetError(C.rbd_lock_exclusive(image.image, c_cookie))
 }
 
-// int rbd_lock_shared(rbd_image_t image, const char *cookie, const char *tag);
+// LockShared acquires a shared lock on the rbd image.
+//
+// Implements:
+//  int rbd_lock_shared(rbd_image_t image, const char *cookie, const char *tag);
 func (image *Image) LockShared(cookie string, tag string) error {
 	if err := image.validate(imageIsOpen); err != nil {
 		return err
@@ -752,7 +793,10 @@ func (image *Image) LockShared(cookie string, tag string) error {
 	return GetError(C.rbd_lock_shared(image.image, c_cookie, c_tag))
 }
 
-// int rbd_lock_shared(rbd_image_t image, const char *cookie, const char *tag);
+// Unlock releases a lock on the image.
+//
+// Implements:
+//  int rbd_lock_shared(rbd_image_t image, const char *cookie, const char *tag);
 func (image *Image) Unlock(cookie string) error {
 	if err := image.validate(imageIsOpen); err != nil {
 		return err
@@ -764,7 +808,10 @@ func (image *Image) Unlock(cookie string) error {
 	return GetError(C.rbd_unlock(image.image, c_cookie))
 }
 
-// int rbd_break_lock(rbd_image_t image, const char *client, const char *cookie);
+// BreakLock forces the release of a lock held by another client.
+//
+// Implements:
+//  int rbd_break_lock(rbd_image_t image, const char *client, const char *cookie);
 func (image *Image) BreakLock(client string, cookie string) error {
 	if err := image.validate(imageIsOpen); err != nil {
 		return err
@@ -787,7 +834,7 @@ func (image *Image) BreakLock(client string, cookie string) error {
 //              const char *fromsnapname,
 //              uint64_t ofs, uint64_t len,
 //              int (*cb)(uint64_t, size_t, int, void *), void *arg);
-func (image *Image) Read(data []byte) (n int, err error) {
+func (image *Image) Read(data []byte) (int, error) {
 	if err := image.validate(imageIsOpen); err != nil {
 		return 0, err
 	}
@@ -807,7 +854,7 @@ func (image *Image) Read(data []byte) (n int, err error) {
 	}
 
 	image.offset += int64(ret)
-	if ret < n {
+	if ret < len(data) {
 		return ret, io.EOF
 	}
 
@@ -866,7 +913,7 @@ func (image *Image) Discard(ofs uint64, length uint64) (int, error) {
 	return int(ret), nil
 }
 
-func (image *Image) ReadAt(data []byte, off int64) (n int, err error) {
+func (image *Image) ReadAt(data []byte, off int64) (int, error) {
 	if err := image.validate(imageIsOpen); err != nil {
 		return 0, err
 	}
@@ -885,7 +932,7 @@ func (image *Image) ReadAt(data []byte, off int64) (n int, err error) {
 		return 0, RBDError(ret)
 	}
 
-	if ret < n {
+	if ret < len(data) {
 		return ret, io.EOF
 	}