Commit Graph

12 Commits

Author SHA1 Message Date
Rick Macklem
90d2dfab19 Merge the pNFS server code from projects/pnfs-planb-server into head.
This code merge adds a pNFS service to the NFSv4.1 server. Although it is
a large commit it should not affect behaviour for a non-pNFS NFS server.
Some documentation on how this works can be found at:
http://people.freebsd.org/~rmacklem/pnfs-planb-setup.txt
and will hopefully be turned into a proper document soon.
This is a merge of the kernel code. Userland and man page changes will
come soon, once the dust settles on this merge.
It has passed a "make universe", so I hope it will not cause build problems.
It also adds NFSv4.1 server support for the "current stateid".

Here is a brief overview of the pNFS service:
A pNFS service separates the Read/Write oeprations from all the other NFSv4.1
Metadata operations. It is hoped that this separation allows a pNFS service
to be configured that exceeds the limits of a single NFS server for either
storage capacity and/or I/O bandwidth.
It is possible to configure mirroring within the data servers (DSs) so that
the data storage file for an MDS file will be mirrored on two or more of
the DSs.
When this is used, failure of a DS will not stop the pNFS service and a
failed DS can be recovered once repaired while the pNFS service continues
to operate.  Although two way mirroring would be the norm, it is possible
to set a mirroring level of up to four or the number of DSs, whichever is
less.
The Metadata server will always be a single point of failure,
just as a single NFS server is.

A Plan B pNFS service consists of a single MetaData Server (MDS) and K
Data Servers (DS), all of which are recent FreeBSD systems.
Clients will mount the MDS as they would a single NFS server.
When files are created, the MDS creates a file tree identical to what a
single NFS server creates, except that all the regular (VREG) files will
be empty. As such, if you look at the exported tree on the MDS directly
on the MDS server (not via an NFS mount), the files will all be of size 0.
Each of these files will also have two extended attributes in the system
attribute name space:
pnfsd.dsfile - This extended attrbute stores the information that
    the MDS needs to find the data storage file(s) on DS(s) for this file.
pnfsd.dsattr - This extended attribute stores the Size, AccessTime, ModifyTime
    and Change attributes for the file, so that the MDS doesn't need to
    acquire the attributes from the DS for every Getattr operation.
For each regular (VREG) file, the MDS creates a data storage file on one
(or more if mirroring is enabled) of the DSs in one of the "dsNN"
subdirectories.  The name of this file is the file handle
of the file on the MDS in hexadecimal so that the name is unique.
The DSs use subdirectories named "ds0" to "dsN" so that no one directory
gets too large. The value of "N" is set via the sysctl vfs.nfsd.dsdirsize
on the MDS, with the default being 20.
For production servers that will store a lot of files, this value should
probably be much larger.
It can be increased when the "nfsd" daemon is not running on the MDS,
once the "dsK" directories are created.

For pNFS aware NFSv4.1 clients, the FreeBSD server will return two pieces
of information to the client that allows it to do I/O directly to the DS.
DeviceInfo - This is relatively static information that defines what a DS
             is. The critical bits of information returned by the FreeBSD
             server is the IP address of the DS and, for the Flexible
             File layout, that NFSv4.1 is to be used and that it is
             "tightly coupled".
             There is a "deviceid" which identifies the DeviceInfo.
Layout     - This is per file and can be recalled by the server when it
             is no longer valid. For the FreeBSD server, there is support
             for two types of layout, call File and Flexible File layout.
             Both allow the client to do I/O on the DS via NFSv4.1 I/O
             operations. The Flexible File layout is a more recent variant
             that allows specification of mirrors, where the client is
             expected to do writes to all mirrors to maintain them in a
             consistent state. The Flexible File layout also allows the
             client to report I/O errors for a DS back to the MDS.
             The Flexible File layout supports two variants referred to as
             "tightly coupled" vs "loosely coupled". The FreeBSD server always
             uses the "tightly coupled" variant where the client uses the
             same credentials to do I/O on the DS as it would on the MDS.
             For the "loosely coupled" variant, the layout specifies a
             synthetic user/group that the client uses to do I/O on the DS.
             The FreeBSD server does not do striping and always returns
             layouts for the entire file. The critical information in a layout
             is Read vs Read/Writea and DeviceID(s) that identify which
             DS(s) the data is stored on.

At this time, the MDS generates File Layout layouts to NFSv4.1 clients
that know how to do pNFS for the non-mirrored DS case unless the sysctl
vfs.nfsd.default_flexfile is set non-zero, in which case Flexible File
layouts are generated.
The mirrored DS configuration always generates Flexible File layouts.
For NFS clients that do not support NFSv4.1 pNFS, all I/O operations
are done against the MDS which acts as a proxy for the appropriate DS(s).
When the MDS receives an I/O RPC, it will do the RPC on the DS as a proxy.
If the DS is on the same machine, the MDS/DS will do the RPC on the DS as
a proxy and so on, until the machine runs out of some resource, such as
session slots or mbufs.
As such, DSs must be separate systems from the MDS.

Tested by:	james.rose@framestore.com
Relnotes:	yes
2018-06-12 19:36:32 +00:00
Pedro F. Giffuni
51369649b0 sys: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
2017-11-20 19:43:44 +00:00
Rick Macklem
47cbff34fa Add kernel support for the NFS client forced dismount "umount -N" option.
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
2017-07-29 19:52:47 +00:00
Warner Losh
fbbd9655e5 Renumber copyright clause 4
Renumber cluase 4 to 3, per what everybody else did when BSD granted
them permission to remove clause 3. My insistance on keeping the same
numbering for legal reasons is too pedantic, so give up on that point.

Submitted by:	Jan Schaumann <jschauma@stevens.edu>
Pull Request:	https://github.com/freebsd/freebsd/pull/96
2017-02-28 23:42:47 +00:00
Rick Macklem
84be7e0952 Add kernel support to the NFS server for the "-manage-gids"
option that will be added to the nfsuserd daemon in a future
commit. It modifies the cache used by NFSv4 for name<-->id
translation (both username/uid and group/gid) to support this.
When "-manage-gids" is set, the server looks up each uid
for the RPC and uses the list of groups cached in the server
instead of the list of groups provided in the RPC request.
The cached group list is acquired for the cache by the nfsuserd
daemon via getgrouplist(3).
This avoids the 16 groups limit for the list in the RPC request.
Since the cache is now used for every RPC when "-manage-gids"
is enabled, the code also modifies the cache to use a separate
mutex for each hash list instead of a single global mutex.

Suggested by:	jpaetzel
Tested by:	jpaetzel
MFC after:	2 weeks
2015-11-30 21:54:27 +00:00
Rick Macklem
99d2727d67 Add an nfssvc() option to the kernel for the new NFS client
which dumps out the actual options being used by an NFS mount.
This will be used to implement a "-m" option for nfsstat(1).

Reviewed by:	alfred
MFC after:	2 weeks
2012-12-02 01:16:04 +00:00
Rick Macklem
6001db296e Add two new options to the nfssvc(2) syscall that allow
processes running as root to suspend/resume execution
of the kernel nfsd threads. An earlier version of this
patch was tested by Vincent Hoffman (vince at unsane.co.uk)
and John Hickey (jh at deterlab.net).

Reviewed by:	kib
MFC after:	2 weeks
2012-10-14 22:33:17 +00:00
Rick Macklem
2e3b981a4d Add kernel support for NFSSVC_ZEROCLTSTATS and NFSSVC_ZEROSRVSTATS
so that they can be used by nfsstat(1) to implement the "-z" option
for the new NFS subsystem.

MFC after:	2 weeks
2011-05-04 13:36:18 +00:00
Rick Macklem
2b08b570cb Revert r221306, since NFSSVC_ZEROSTATS zero'd both client and
server stats, when separate modifiers for NFSSVC_GETSTATS for
each of client and server stats is what it required by nfsstat(1).
2011-05-04 13:30:38 +00:00
Rick Macklem
b2946fadcd Add the kernel support needed to zero out the nfsstats
structure for the new NFS subsystem. This will be used
by nfsstats.c to implement the "-z" option.

MFC after:	2 weeks
2011-05-01 22:19:52 +00:00
Rick Macklem
5f73287a6e Modify the experimental NFSv4 server so that it posts a SIGUSR2
signal to the master nfsd daemon whenever the stable restart
file has been modified. This will allow the master nfsd daemon
to maintain an up to date backup copy of the file. This is
enabled via the nfssvc() syscall, so that older nfsd daemons
will not be signaled.

Reviewed by:	jhb
MFC after:	1 week
2011-01-14 23:30:35 +00:00
Rick Macklem
2a536430e9 Adding sys/nfs/nfssvc.h and sys/nfs/nfs_nfssvc.c in preparation for
sharing of the nfssvc() system call between nfsserver and the nfsv4
	server. Building of nfs_nfssvc.c will be committed later, at the time
	the .c files in sys/nfsserver are updated. To do so now would result in
	nfssvc() multiply defined.

Submitted by:	rmacklem
Reviewed by:	dfr
Approved by:	kib (mentor)
2009-04-07 19:06:51 +00:00