This patch adds "vers" and "minorvers" arguments to nfscl_reqstart().
The patch always passes them in as "0" and that implies no change
in semantics. These arguments will be used by a future commit that
adds support for the Flexible File Layout.
When an NFS mount is hung against an unresponsive NFS server, the "umount -f"
option can be used to dismount the mount. Unfortunately, "umount -f" gets
hung as well if a "umount" without "-f" has already been done. Usually,
this is because of a vnode lock being held by the "umount" for the mounted-on
vnode.
This patch adds kernel code so that a new "-N" option can be added to "umount",
allowing it to avoid getting hung for this case.
It adds two flags. One indicates that a forced dismount is about to happen
and the other is used, along with setting mnt_data == NULL, to handshake
with the nfs_unmount() VFS call.
It includes a slight change to the interface used between the client and
common NFS modules, so I bumped __FreeBSD_version to ensure both modules are
rebuilt.
Tested by: pho
Reviewed by: kib
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D11735
This patch defines a macro that checks for MNTK_UNMOUNTF and replaces
explicit checks with this macro. It has no effect on semantics, but
prepares the code for a future patch where there will also be a
NFS specific flag for "forced dismount about to occur".
Suggested by: kib
MFC after: 2 weeks
to head. I don't think the NFS client behaviour will change unless
the new "minorversion=1" mount option is used. It includes basic
NFSv4.1 support plus support for pNFS using the Files Layout only.
All problems detecting during an NFSv4.1 Bakeathon testing event
in June 2012 have been resolved in this code and it has been tested
against the NFSv4.1 server available to me.
Although not reviewed, I believe that kib@ has looked at it.
Use it for a printf() that can be harmlessly generated for mmap()'d
files. It will be used extensively for the NFSv4.1 client.
Debugging printf()s are enabled by setting vfs.nfs.debuglevel to
a non-zero value. The higher the value, the more debugging printf()s.
Reviewed by: jhb
MFC after: 2 weeks
support for NFSv4 as well as NFSv2 and 3.
It lives in 3 subdirs under sys/fs:
nfs - functions that are common to the client and server
nfsclient - a mutation of sys/nfsclient that call generic functions
to do RPCs and handle state. As such, it retains the
buffer cache handling characteristics and vnode semantics that
are found in sys/nfsclient, for the most part.
nfsserver - the server. It includes a DRC designed specifically for
NFSv4, that is used instead of the generic DRC in sys/rpc.
The build glue will be checked in later, so at this point, it
consists of 3 new subdirs that should not affect kernel building.
Approved by: kib (mentor)
