diff --git a/gst/gstbuffer.c b/gst/gstbuffer.c
index 9b5c380837..3a63a6495f 100644
--- a/gst/gstbuffer.c
+++ b/gst/gstbuffer.c
@@ -456,7 +456,8 @@ gst_buffer_new (void)
 
 /**
  * gst_buffer_new_allocate:
- * @allocator: the #GstAllocator to use
+ * @allocator: (allow-none): the #GstAllocator to use, or NULL to use the
+ *     default allocator
  * @size: the size in bytes of the new buffer's data.
  * @align: the alignment of the buffer memory
  *
@@ -807,12 +808,12 @@ gst_buffer_get_sizes (GstBuffer * buffer, gsize * offset, gsize * maxsize)
  * gst_buffer_resize:
  * @buffer: a #GstBuffer.
  * @offset: the offset adjustement
- * @size: the new size
+ * @size: the new size or -1 to just adjust the offset
  *
  * Set the total size of the buffer
  */
 void
-gst_buffer_resize (GstBuffer * buffer, gssize offset, gsize size)
+gst_buffer_resize (GstBuffer * buffer, gssize offset, gssize size)
 {
   guint len;
   guint i;
@@ -824,8 +825,8 @@ gst_buffer_resize (GstBuffer * buffer, gssize offset, gsize size)
   bufsize = gst_buffer_get_sizes (buffer, &bufoffs, &bufmax);
 
   GST_CAT_LOG (GST_CAT_BUFFER, "trim %p %" G_GSSIZE_FORMAT "-%" G_GSIZE_FORMAT
-      " size:%" G_GSIZE_FORMAT " offs:%" G_GSIZE_FORMAT " max:%" G_GSIZE_FORMAT,
-      buffer, offset, size, bufsize, bufoffs, bufmax);
+      " size:%" G_GSIZE_FORMAT " offs:%" G_GSSIZE_FORMAT " max:%"
+      G_GSIZE_FORMAT, buffer, offset, size, bufsize, bufoffs, bufmax);
 
   /* we can't go back further than the current offset or past the end of the
    * buffer */
@@ -987,7 +988,7 @@ not_writable:
  * gst_buffer_unmap:
  * @buffer: a #GstBuffer.
  * @data: the previously mapped data
- * @size: the size of @data
+ * @size: the size of @data, or -1
  *
  * Release the memory previously mapped with gst_buffer_map(). Pass -1 to size
  * if no update is needed.
@@ -996,12 +997,13 @@ not_writable:
  * than the maxsize of the memory.
  */
 gboolean
-gst_buffer_unmap (GstBuffer * buffer, gpointer data, gsize size)
+gst_buffer_unmap (GstBuffer * buffer, gpointer data, gssize size)
 {
   gboolean result;
   guint len;
 
   g_return_val_if_fail (GST_IS_BUFFER (buffer), FALSE);
+  g_return_val_if_fail (size >= -1, FALSE);
 
   len = GST_BUFFER_MEM_LEN (buffer);
 
diff --git a/gst/gstbuffer.h b/gst/gstbuffer.h
index f3b727788b..46a60f545f 100644
--- a/gst/gstbuffer.h
+++ b/gst/gstbuffer.h
@@ -295,7 +295,7 @@ gsize       gst_buffer_memset              (GstBuffer *buffer, gsize offset,
                                             guint8 val, gsize size);
 
 gsize       gst_buffer_get_sizes           (GstBuffer *buffer, gsize *offset, gsize *maxsize);
-void        gst_buffer_resize              (GstBuffer *buffer, gssize offset, gsize size);
+void        gst_buffer_resize              (GstBuffer *buffer, gssize offset, gssize size);
 
 /**
  * gst_buffer_get_size:
@@ -317,7 +317,7 @@ void        gst_buffer_resize              (GstBuffer *buffer, gssize offset, gs
 /* getting memory */
 gpointer    gst_buffer_map                 (GstBuffer *buffer, gsize *size, gsize *maxsize,
                                             GstMapFlags flags);
-gboolean    gst_buffer_unmap               (GstBuffer *buffer, gpointer data, gsize size);
+gboolean    gst_buffer_unmap               (GstBuffer *buffer, gpointer data, gssize size);
 
 /* refcounting */
 /**
diff --git a/gst/gstmemory.c b/gst/gstmemory.c
index e709396011..b2ac925929 100644
--- a/gst/gstmemory.c
+++ b/gst/gstmemory.c
@@ -278,7 +278,7 @@ _default_mem_is_span (GstMemoryDefault * mem1, GstMemoryDefault * mem2,
 }
 
 static GstMemory *
-_fallback_copy (GstMemory * mem, gssize offset, gsize size)
+_fallback_copy (GstMemory * mem, gssize offset, gssize size)
 {
   GstMemory *copy;
   guint8 *data, *dest;
@@ -465,7 +465,7 @@ gst_memory_map (GstMemory * mem, gsize * size, gsize * maxsize,
  * gst_memory_unmap:
  * @mem: a #GstMemory
  * @data: data to unmap
- * @size: new size of @mem
+ * @size: new size of @mem, or -1
  *
  * Release the memory pointer obtained with gst_memory_map() and set the size of
  * the memory to @size. @size can be set to -1 when the size should not be
@@ -474,7 +474,7 @@ gst_memory_map (GstMemory * mem, gsize * size, gsize * maxsize,
  * Returns: TRUE when the memory was release successfully.
  */
 gboolean
-gst_memory_unmap (GstMemory * mem, gpointer data, gsize size)
+gst_memory_unmap (GstMemory * mem, gpointer data, gssize size)
 {
   g_return_val_if_fail (mem != NULL, FALSE);
 
@@ -485,7 +485,7 @@ gst_memory_unmap (GstMemory * mem, gpointer data, gsize size)
  * gst_memory_copy:
  * @mem: a #GstMemory
  * @offset: an offset to copy
- * @size: size to copy
+ * @size: size to copy or -1 to copy all bytes from offset
  *
  * Return a copy of @size bytes from @mem starting from @offset. This copy is
  * guaranteed to be writable. @size can be set to -1 to return a copy all bytes
@@ -494,7 +494,7 @@ gst_memory_unmap (GstMemory * mem, gpointer data, gsize size)
  * Returns: a new #GstMemory.
  */
 GstMemory *
-gst_memory_copy (GstMemory * mem, gssize offset, gsize size)
+gst_memory_copy (GstMemory * mem, gssize offset, gssize size)
 {
   g_return_val_if_fail (mem != NULL, NULL);
 
@@ -505,17 +505,17 @@ gst_memory_copy (GstMemory * mem, gssize offset, gsize size)
  * gst_memory_share:
  * @mem: a #GstMemory
  * @offset: an offset to share
- * @size: size to share
+ * @size: size to share or -1 to share bytes from offset
  *
- * Return a shared copy of @size bytes from @mem starting from @offset. No memory
- * copy is performed and the memory region is simply shared. The result is
- * guaranteed to be not-writable. @size can be set to -1 to return a share all bytes
- * from @offset.
+ * Return a shared copy of @size bytes from @mem starting from @offset. No
+ * memory copy is performed and the memory region is simply shared. The result
+ * is guaranteed to be not-writable. @size can be set to -1 to return a share
+ * all bytes from @offset.
  *
  * Returns: a new #GstMemory.
  */
 GstMemory *
-gst_memory_share (GstMemory * mem, gssize offset, gsize size)
+gst_memory_share (GstMemory * mem, gssize offset, gssize size)
 {
   g_return_val_if_fail (mem != NULL, NULL);
 
diff --git a/gst/gstmemory.h b/gst/gstmemory.h
index c4d618706f..9215e47cc3 100644
--- a/gst/gstmemory.h
+++ b/gst/gstmemory.h
@@ -143,7 +143,7 @@ typedef gsize       (*GstMemoryGetSizesFunction)  (GstMemory *mem, gsize *offset
  * GstMemoryResizeFunction:
  * @mem: a #GstMemory
  * @offset: the offset adjustement
- * @size: the new size
+ * @size: the new size or -1 to just adjust the offset
  *
  * Adjust the size and offset of @mem. @offset bytes will be adjusted from the
  * current first byte in @mem as retrieved with gst_memory_map() and the new
@@ -151,7 +151,7 @@ typedef gsize       (*GstMemoryGetSizesFunction)  (GstMemory *mem, gsize *offset
  *
  * @size can be set to -1, which will only adjust the offset.
  */
-typedef void        (*GstMemoryResizeFunction)    (GstMemory *mem, gssize offset, gsize size);
+typedef void        (*GstMemoryResizeFunction)    (GstMemory *mem, gssize offset, gssize size);
 
 /**
  * GstMemoryMapFunction:
@@ -175,7 +175,7 @@ typedef gpointer    (*GstMemoryMapFunction)       (GstMemory *mem, gsize *size,
  * GstMemoryUnmapFunction:
  * @mem: a #GstMemory
  * @data: the data pointer
- * @size: the new size
+ * @size: the new size, or -1 to not modify the size
  *
  * Return the pointer previously retrieved with gst_memory_map() and adjust the
  * size of the memory with @size. @size can optionally be set to -1 to not
@@ -183,7 +183,7 @@ typedef gpointer    (*GstMemoryMapFunction)       (GstMemory *mem, gsize *size,
  *
  * Returns: %TRUE on success.
  */
-typedef gboolean    (*GstMemoryUnmapFunction)     (GstMemory *mem, gpointer data, gsize size);
+typedef gboolean    (*GstMemoryUnmapFunction)     (GstMemory *mem, gpointer data, gssize size);
 
 /**
  * GstMemoryFreeFunction:
@@ -198,7 +198,7 @@ typedef void        (*GstMemoryFreeFunction)      (GstMemory *mem);
  * GstMemoryCopyFunction:
  * @mem: a #GstMemory
  * @offset: an offset
- * @size: a size
+ * @size: a size or -1
  *
  * Copy @size bytes from @mem starting at @offset and return them wrapped in a
  * new GstMemory object.
@@ -207,13 +207,13 @@ typedef void        (*GstMemoryFreeFunction)      (GstMemory *mem);
  * Returns: a new #GstMemory object wrapping a copy of the requested region in
  * @mem.
  */
-typedef GstMemory * (*GstMemoryCopyFunction)      (GstMemory *mem, gssize offset, gsize size);
+typedef GstMemory * (*GstMemoryCopyFunction)      (GstMemory *mem, gssize offset, gssize size);
 
 /**
  * GstMemoryShareFunction:
  * @mem: a #GstMemory
  * @offset: an offset
- * @size: a size
+ * @size: a size or -1
  *
  * Share @size bytes from @mem starting at @offset and return them wrapped in a
  * new GstMemory object. If @size is set to -1, all bytes starting at @offset are
@@ -221,7 +221,7 @@ typedef GstMemory * (*GstMemoryCopyFunction)      (GstMemory *mem, gssize offset
  *
  * Returns: a new #GstMemory object sharing the requested region in @mem.
  */
-typedef GstMemory * (*GstMemoryShareFunction)     (GstMemory *mem, gssize offset, gsize size);
+typedef GstMemory * (*GstMemoryShareFunction)     (GstMemory *mem, gssize offset, gssize size);
 
 /**
  * GstMemoryIsSpanFunction:
@@ -291,11 +291,11 @@ void        gst_memory_resize     (GstMemory *mem, gssize offset, gsize size);
 /* retrieving data */
 gpointer    gst_memory_map        (GstMemory *mem, gsize *size, gsize *maxsize,
                                    GstMapFlags flags);
-gboolean    gst_memory_unmap      (GstMemory *mem, gpointer data, gsize size);
+gboolean    gst_memory_unmap      (GstMemory *mem, gpointer data, gssize size);
 
 /* copy and subregions */
-GstMemory * gst_memory_copy       (GstMemory *mem, gssize offset, gsize size);
-GstMemory * gst_memory_share      (GstMemory *mem, gssize offset, gsize size);
+GstMemory * gst_memory_copy       (GstMemory *mem, gssize offset, gssize size);
+GstMemory * gst_memory_share      (GstMemory *mem, gssize offset, gssize size);
 
 /* span memory */
 gboolean    gst_memory_is_span    (GstMemory *mem1, GstMemory *mem2, gsize *offset);