| From: | Matthew Dillon <dillon@xxxxxxxxxxxxxxxxxxxx> |
| Date: | Fri, 7 Sep 2012 09:35:31 -0700 (PDT) |
:hi, all
:(thanx for the links to the books)
:
:i have added few handlers to
:my_vnops.c file (that originally was null_vnops.c of "nullfs")
:
:and (with intention to involve my handlers into execution flow)
:i have extended struct vop_ops (last 4 lines):
:
:struct vop_ops my_vnode_vops = {
: .vop_nresolve = null_nresolve,
: .vop_ncreate = null_ncreate,
: .vop_nmkdir = null_nmkdir,
: .vop_nmknod = null_nmknod,
: .vop_nlink = null_nlink,
: .vop_nsymlink = null_nsymlink,
: .vop_nwhiteout = null_nwhiteout,
: .vop_nremove = null_nremove,
: .vop_nrmdir = null_nrmdir,
: .vop_nrename = null_nrename,
: .vop_mountctl = null_mountctl,
: .vop_open = my_open,
: .vop_read = my_read,
: .vop_write = my_write,
: .vop_access = my_access
:};
:
:then i have noticed that my_*() handlers were never called no matter what operations i perform on my test subject.
:
:the question is:
:(1) What am i doing wrong?
:(2) Is there any official description what is a purpose of each handler in struct vop_ops and WHEN it shall be called?
This won't work for a nullfs mount because the underyling vnodes are
the vnodes for the underyling filesystem, NOT nullfs-specific vnodes.
Thus those vnodes point to the underlying filesystem's ops and not
nullfs's ops.
If you want to try your hand at creating your own filesystem then I
recommend starting with a self-contained memory filesystem like tmpfs.
-Matt
Matthew Dillon
<dillon@backplane.com>