1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
|
=============================
NFSv4.1 Server Implementation
=============================
Server support for minorversion 1 can be controlled using the
/proc/fs/nfsd/versions control file. The string output returned
by reading this file will contain either "+4.1" or "-4.1"
correspondingly.
Currently, server support for minorversion 1 is enabled by default.
It can be disabled at run time by writing the string "-4.1" to
the /proc/fs/nfsd/versions control file. Note that to write this
control file, the nfsd service must be taken down. You can use rpc.nfsd
for this; see rpc.nfsd(8).
(Warning: older servers will interpret "+4.1" and "-4.1" as "+4" and
"-4", respectively. Therefore, code meant to work on both new and old
kernels must turn 4.1 on or off *before* turning support for version 4
on or off; rpc.nfsd does this correctly.)
The NFSv4 minorversion 1 (NFSv4.1) implementation in nfsd is based
on RFC 5661.
From the many new features in NFSv4.1 the current implementation
focuses on the mandatory-to-implement NFSv4.1 Sessions, providing
"exactly once" semantics and better control and throttling of the
resources allocated for each client.
The table below, taken from the NFSv4.1 document, lists
the operations that are mandatory to implement (REQ), optional
(OPT), and NFSv4.0 operations that are required not to implement (MNI)
in minor version 1. The first column indicates the operations that
are not supported yet by the linux server implementation.
The OPTIONAL features identified and their abbreviations are as follows:
- **pNFS** Parallel NFS
- **FDELG** File Delegations
- **DDELG** Directory Delegations
The following abbreviations indicate the linux server implementation status.
- **I** Implemented NFSv4.1 operations.
- **NS** Not Supported.
- **NS\*** Unimplemented optional feature.
Operations
==========
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| Implementation status | Operation | REQ,REC, OPT or NMI | Feature (REQ, REC or OPT) | Definition |
+=======================+======================+=====================+===========================+================+
| | ACCESS | REQ | | Section 18.1 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| I | BACKCHANNEL_CTL | REQ | | Section 18.33 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| I | BIND_CONN_TO_SESSION | REQ | | Section 18.34 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | CLOSE | REQ | | Section 18.2 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | COMMIT | REQ | | Section 18.3 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | CREATE | REQ | | Section 18.4 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| I | CREATE_SESSION | REQ | | Section 18.36 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| NS* | DELEGPURGE | OPT | FDELG (REQ) | Section 18.5 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | DELEGRETURN | OPT | FDELG, | Section 18.6 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | | | DDELG, pNFS | |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | | | (REQ) | |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| I | DESTROY_CLIENTID | REQ | | Section 18.50 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| I | DESTROY_SESSION | REQ | | Section 18.37 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| I | EXCHANGE_ID | REQ | | Section 18.35 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| I | FREE_STATEID | REQ | | Section 18.38 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | GETATTR | REQ | | Section 18.7 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| I | GETDEVICEINFO | OPT | pNFS (REQ) | Section 18.40 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| NS* | GETDEVICELIST | OPT | pNFS (OPT) | Section 18.41 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | GETFH | REQ | | Section 18.8 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| NS* | GET_DIR_DELEGATION | OPT | DDELG (REQ) | Section 18.39 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| I | LAYOUTCOMMIT | OPT | pNFS (REQ) | Section 18.42 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| I | LAYOUTGET | OPT | pNFS (REQ) | Section 18.43 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| I | LAYOUTRETURN | OPT | pNFS (REQ) | Section 18.44 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | LINK | OPT | | Section 18.9 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | LOCK | REQ | | Section 18.10 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | LOCKT | REQ | | Section 18.11 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | LOCKU | REQ | | Section 18.12 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | LOOKUP | REQ | | Section 18.13 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | LOOKUPP | REQ | | Section 18.14 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | NVERIFY | REQ | | Section 18.15 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | OPEN | REQ | | Section 18.16 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| NS* | OPENATTR | OPT | | Section 18.17 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | OPEN_CONFIRM | MNI | | N/A |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | OPEN_DOWNGRADE | REQ | | Section 18.18 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | PUTFH | REQ | | Section 18.19 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | PUTPUBFH | REQ | | Section 18.20 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | PUTROOTFH | REQ | | Section 18.21 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | READ | REQ | | Section 18.22 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | READDIR | REQ | | Section 18.23 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | READLINK | OPT | | Section 18.24 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | RECLAIM_COMPLETE | REQ | | Section 18.51 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | RELEASE_LOCKOWNER | MNI | | N/A |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | REMOVE | REQ | | Section 18.25 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | RENAME | REQ | | Section 18.26 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | RENEW | MNI | | N/A |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | RESTOREFH | REQ | | Section 18.27 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | SAVEFH | REQ | | Section 18.28 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | SECINFO | REQ | | Section 18.29 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| I | SECINFO_NO_NAME | REC | pNFS files | Section 18.45, |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | | | layout (REQ) | Section 13.12 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| I | SEQUENCE | REQ | | Section 18.46 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | SETATTR | REQ | | Section 18.30 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | SETCLIENTID | MNI | | N/A |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | SETCLIENTID_CONFIRM | MNI | | N/A |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| NS | SET_SSV | REQ | | Section 18.47 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| I | TEST_STATEID | REQ | | Section 18.48 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | VERIFY | REQ | | Section 18.31 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| NS* | WANT_DELEGATION | OPT | FDELG (OPT) | Section 18.49 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
| | WRITE | REQ | | Section 18.32 |
+-----------------------+----------------------+---------------------+---------------------------+----------------+
Callback Operations
===================
+-----------------------+-------------------------+---------------------+---------------------------+---------------+
| Implementation status | Operation | REQ,REC, OPT or NMI | Feature (REQ, REC or OPT) | Definition |
+=======================+=========================+=====================+===========================+===============+
| | CB_GETATTR | OPT | FDELG (REQ) | Section 20.1 |
+-----------------------+-------------------------+---------------------+---------------------------+---------------+
| I | CB_LAYOUTRECALL | OPT | pNFS (REQ) | Section 20.3 |
+-----------------------+-------------------------+---------------------+---------------------------+---------------+
| NS* | CB_NOTIFY | OPT | DDELG (REQ) | Section 20.4 |
+-----------------------+-------------------------+---------------------+---------------------------+---------------+
| NS* | CB_NOTIFY_DEVICEID | OPT | pNFS (OPT) | Section 20.12 |
+-----------------------+-------------------------+---------------------+---------------------------+---------------+
| NS* | CB_NOTIFY_LOCK | OPT | | Section 20.11 |
+-----------------------+-------------------------+---------------------+---------------------------+---------------+
| NS* | CB_PUSH_DELEG | OPT | FDELG (OPT) | Section 20.5 |
+-----------------------+-------------------------+---------------------+---------------------------+---------------+
| | CB_RECALL | OPT | FDELG, | Section 20.2 |
+-----------------------+-------------------------+---------------------+---------------------------+---------------+
| | | | DDELG, pNFS | |
+-----------------------+-------------------------+---------------------+---------------------------+---------------+
| | | | (REQ) | |
+-----------------------+-------------------------+---------------------+---------------------------+---------------+
| NS* | CB_RECALL_ANY | OPT | FDELG, | Section 20.6 |
+-----------------------+-------------------------+---------------------+---------------------------+---------------+
| | | | DDELG, pNFS | |
+-----------------------+-------------------------+---------------------+---------------------------+---------------+
| | | | (REQ) | |
+-----------------------+-------------------------+---------------------+---------------------------+---------------+
| NS | CB_RECALL_SLOT | REQ | | Section 20.8 |
+-----------------------+-------------------------+---------------------+---------------------------+---------------+
| NS* | CB_RECALLABLE_OBJ_AVAIL | OPT | DDELG, pNFS | Section 20.7 |
+-----------------------+-------------------------+---------------------+---------------------------+---------------+
| | | | (REQ) | |
+-----------------------+-------------------------+---------------------+---------------------------+---------------+
| I | CB_SEQUENCE | OPT | FDELG, | Section 20.9 |
+-----------------------+-------------------------+---------------------+---------------------------+---------------+
| | | | DDELG, pNFS | |
+-----------------------+-------------------------+---------------------+---------------------------+---------------+
| | | | (REQ) | |
+-----------------------+-------------------------+---------------------+---------------------------+---------------+
| NS* | CB_WANTS_CANCELLED | OPT | FDELG, | Section 20.10 |
+-----------------------+-------------------------+---------------------+---------------------------+---------------+
| | | | DDELG, pNFS | |
+-----------------------+-------------------------+---------------------+---------------------------+---------------+
| | | | (REQ) | |
+-----------------------+-------------------------+---------------------+---------------------------+---------------+
Implementation notes:
=====================
SSV:
The spec claims this is mandatory, but we don't actually know of any
implementations, so we're ignoring it for now. The server returns
NFS4ERR_ENCR_ALG_UNSUPP on EXCHANGE_ID, which should be future-proof.
GSS on the backchannel:
Again, theoretically required but not widely implemented (in
particular, the current Linux client doesn't request it). We return
NFS4ERR_ENCR_ALG_UNSUPP on CREATE_SESSION.
DELEGPURGE:
mandatory only for servers that support CLAIM_DELEGATE_PREV and/or
CLAIM_DELEG_PREV_FH (which allows clients to keep delegations that
persist across client reboots). Thus we need not implement this for
now.
EXCHANGE_ID:
implementation ids are ignored
CREATE_SESSION:
backchannel attributes are ignored
SEQUENCE:
no support for dynamic slot table renegotiation (optional)
Nonstandard compound limitations:
No support for a sessions fore channel RPC compound that requires both a
ca_maxrequestsize request and a ca_maxresponsesize reply, so we may
fail to live up to the promise we made in CREATE_SESSION fore channel
negotiation.
See also http://wiki.linux-nfs.org/wiki/index.php/Server_4.0_and_4.1_issues.
|