code review from Josh and Robert

*** 30,57 ****
  PARAMETERS
       name    A character string giving a name to the vmem arena to be created.
  
       base    An address indicating the lowest possible value in the arena.
  
!      size    The size of the arena to create
  
       quantum
               The arena's ``quantum''.  The granularity of the arena.  The
!              amount allocated at minimum by each request.
  
!      afunc   A function which is called to import new spans from source.
!              Which may be NULL if this arena does not import from another.
  
!      ffunc   A function which is called to return spans to source.  Which may
!              be NULL if this arena does not import from another.
  
!      source  An arena from which this arena will import.  Which may be NULL if
               this arena does not import from another.
  
       qcache_max
               Each arena offers caching of integer multiples of quantum up to
!              qcache_max.
  
       vmflag  A bitmask of flags indicating the characteristics of this arena.
  
               VMC_IDENTIFIER
                       The arena represents arbitrary integer identifiers,
--- 30,93 ----
  PARAMETERS
       name    A character string giving a name to the vmem arena to be created.
  
       base    An address indicating the lowest possible value in the arena.
  
!      size    The size of the arena to create.
  
       quantum
               The arena's ``quantum''.  The granularity of the arena.  The
!              amount allocated at minimum by each request.  Must be a power of
!              2.
  
!      afunc   A function which is called to import new spans from source, which
!              may be NULL if this arena does not import from another.  When
!              calling vmem_create() afunc is an vmem_alloc_t a function taking
!              three parameters and returning a pointer to void (the imported
!              space):
  
!              vmem_t *
!                      The source arena from which we'll import.  The source
!                      argument to vmem_create().
  
!              size_t  The size to import
! 
!              int     The vmflag argument used for the import.
! 
!              When calling vmem_xcreate() afunc is an vmem_ximport_t a function
!              taking four parameters and returning a pointer to void (the
!              imported space):
! 
!              vmem_t *
!                      The source arena from which we'll import.  The source
!                      argument to vmem_xcreate().
! 
!              size_t *
!                      The size of the import, afunc may increase this size if
!                      that is desirable, but must never decrease it.
! 
!              size_t  The desired alignment of the imported space.
! 
!              int     the vmflag argument used for the import.
! 
!      ffunc   A function which is called to return spans to source, which may
!              be NULL if this arena does not import from another.  This is a
!              vmem_free_t a function taking three parametes and returning void:
! 
!              vmem_t  The arena to which space is being returned.  The source
!                      argument to vmem_create() or vmem_xcreate().
! 
!              void *  The span being returned to the source arena.
! 
!              size_t  The size of the span being returned to the source arena.
! 
!      source  An arena from which this arena will import, which may be NULL if
               this arena does not import from another.
  
       qcache_max
               Each arena offers caching of integer multiples of quantum up to
!              qcache_max, which may be 0.
  
       vmflag  A bitmask of flags indicating the characteristics of this arena.
  
               VMC_IDENTIFIER
                       The arena represents arbitrary integer identifiers,
*** 67,83 ****
  
       The afunc, ffunc, and source arguments combine to support a hierarchical
       structure of arenas, each importing from a single parent (the source).
       The vmem_create() and vmem_xcreate() functions differ in that the latter
       provides an interface for afunc to alter the size of the span imported
!      from source.  It is only legal to increase thise size.
  
  CONTEXT
       These functions can be called from user or kernel context.
  
  RETURN VALUES
!      Upon successful completion the vmem_create(and) vmem_xcreate() functions
       return a pointer to a vmem arena.  Otherwise, NULL is returned to
       indicate the arena could not be created.
  
  SEE ALSO
       vmem(9), vmem_add(9F), vmem_alloc(9F)
--- 103,119 ----
  
       The afunc, ffunc, and source arguments combine to support a hierarchical
       structure of arenas, each importing from a single parent (the source).
       The vmem_create() and vmem_xcreate() functions differ in that the latter
       provides an interface for afunc to alter the size of the span imported
!      from source.  It is only legal to increase this size.
  
  CONTEXT
       These functions can be called from user or kernel context.
  
  RETURN VALUES
!      Upon successful completion the vmem_create() and vmem_xcreate() functions
       return a pointer to a vmem arena.  Otherwise, NULL is returned to
       indicate the arena could not be created.
  
  SEE ALSO
       vmem(9), vmem_add(9F), vmem_alloc(9F)