YAMAMOTO Takashi writes:

[...]

 > 
 > i can see your point.  however, i have a different opinion.
 > GOPs and "ufs ops" don't need complexity which VOP has.
 > plain function pointers are just fine.
 > (i doubt if VOPs really need this complexity, but it's another topic.)

Advantage VOPs have over plain function pointers is that stacked file
system can forward a VOP it doesn't understand. That is, if new VOP is
added, old file system modules can work (even without
recompilation).

 > 
 > YAMAMOTO Takashi
 > 

Nikita.