Network Working Group S. Khan
Internet-Draft Author
Document: Network Appliance, Inc.
draft-khan-nfsv4-directory-delegation-00.txt February 2004
NFSv4.1: Directory Delegations and Notifications
Status of this Memo
This document is an Internet-Draft and is subject to all provisions
of Section 10 of RFC2026.
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ABSTRACT
This document proposes adding directory delegations and notifications
to NFS Version 4 [RFC3530]. It is hoped that these changes will be
part of a new minor version of NFS, such as NFSv4.1.
TABLE OF CONTENTS
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Proposed protocol extensions. . . . . . . . . . . . . . . . . 3
3. Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
4. New Operation 40: GET_DIR_DELEGATION - Get a directory
delegation . . . . . . . . . . . . . . . . . . . . . . . . . . 4
5. New Recommended Attributes . . . . . . . . . . . . . . . . . . 7
6. New Callback Operation: CB_NOTIFY - Notify directory changes . 8
7. Delegation Recall . . . . . . . . . . . . . . . . . . . . . 11
8. New Callback Operation: CB_RECALL_ANY - Keep any N
delegations . . . . . . . . . . . . . . . . . . . . . . . . 11
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9. Delegation Recovery . . . . . . . . . . . . . . . . . . . . 12
10. Issues . . . . . . . . . . . . . . . . . . . . . . . . . . 12
10.1. Synchronous vs. Asynchronous notifications . . . . . . . 12
11. RPC Definition File Changes . . . . . . . . . . . . . . . . 13
12. IANA Considerations . . . . . . . . . . . . . . . . . . . . 22
13. Acknowledgements . . . . . . . . . . . . . . . . . . . . . 22
14. Normative References . . . . . . . . . . . . . . . . . . . 22
15. Informative References . . . . . . . . . . . . . . . . . . 23
16. Author's Address . . . . . . . . . . . . . . . . . . . . . 23
17. IPR Notices . . . . . . . . . . . . . . . . . . . . . . . . 23
18. Copyright Notice . . . . . . . . . . . . . . . . . . . . . 23
1. Introduction
This document assumes understanding of the NFSv4.0 specification. It
also assumes that the changes proposed by [talpey] will be present in
the same minor version and that the protocol would need some
adjustment in the event that the session changes are not present.
The major addition to NFS version 4 in the area of caching is the
ability of the server to delegate certain responsibilities to the
client. When the server grants a delegation for a file to a client,
the client receives certain semantic guarentees with respect to the
sharing of that file with other clients. At OPEN, the server may
provide the client either a read or write delegation for the file. If
the client is granted a read delegation, it is assured that no other
client has the ability to write to the file for the duration of the
delegation. If the client is granted a write delegation, the client
is assured that no other client has read or write access to the file.
This reduces network traffic by allowing the client to perform
various operations locally on file data.
Directory caching for the NFS version 4 protocol is similar to
previous versions. Clients typically cache directory information for
a duration determined by the client. At the end of a predefined
timeout, the client will query the server to see if the directory has
been updated. By caching attributes, clients reduce the number of
GETATTR calls made to the server to validate attributes. Furthermore,
frequently accessed files and directories, such as the current
working directory, have their attributes cached on the client so that
some NFS operations can be performed without having to make an RPC
call. By caching name and inode information about most recently
looked up entries in DNLC (Directory Name Lookup Cache), clients do
not need to send LOOKUP calls to the server every time these files
are accessed.
Delegation of directory contents is proposed as an extension for
NFSv4. Such an extension would provide similar traffic reduction
benefits as with file delegations. By allowing clients to cache
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directory contents (in a read-only fashion) while being notified of
changes, the client can avoid making frequent requests to interrogate
the contents of slowly-changing directories, reducing network traffic
and improving client performance.
2. Proposed protocol extensions.
This document includes the definition of protocol extensions to
implement directory delegations. It is believed that these extension
fit within the minor-versioning framework presented in RFC3530,
although careful review on this point needs to be undertaken. As
stated above, these extensions are designed supposing that the
session extensions [talpey] will be present in the same minor
version, as currently seems likely. Some modifications will be
necessary, if that turns out not to be the case.
Mainly in the interests of clarity of presentation, elements within
these extensions are assigned numeric identifiers such as operation
numbers and attribute identitifies. It should be understood that
when these extensions are included in a minor version of NFSv4, the
actual numeric identifiers assigned may be different from the ones
chosen here.
3. Design
A client gets a directory delegation by use of a new operation
(GET_DIR_DELEGATION) and also informs the server if it wants to be
notified of any changes that are made to the directory. If the server
is unable to notify the client of some set of changes, it should
inform the client of its inability to do so. The server will send
notifications for all change events it has agreed to. Because true
synchronous notification poses significant server implementation
difficulties, the document describes just an asynchronous approach.
The clients are notified of changes to the directory only after the
change has been processed by the server. See the section "Synchronous
vs. Asynchronous notifications" for a discussion on different types
of notifications and the reason for choosing asynchronous
notifications. The delegation is read only and the client may not
make changes to the directory other than by performing NFSv4
operations that modify the directory or the associated file
attributes so that the server has knowledge of these changes. If a
client holding the delegation makes any changes to the directory, it
will not be notified and the delegation will not be recalled. The
client making changes is presumed not to need notifications of
changes that it itself is making.
Delegations can be recalled by the server. The server is free to
recall the delegation at any time. Normally, the server will recall
the delegation when the directory changes in a way that is not
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covered by the notification, or when there is a directory change and
notifications have not been requested.
Also if the server notices that handing out a delegation for a
directory is causing too many notifications to be sent out, it may
decide not to hand out a delegation for that directory or recall
existing delegations. If another client removes the directory for
which a delegation has been granted, the server will recall the
delegation.
Both the notification and recall operations need a callback path to
exist between the client and server. If the callback path does not
exist, then delegations should not be granted. Note that with the
session extensions [talpey] that should not be an issue.
4. New Operation 40: GET_DIR_DELEGATION - Get a directory delegation
SYNOPSIS
(cfh), notification, claim -> (cfh), cookieverf, stateid,
notification
ARGUMENT
struct GET_DIR_DELEGATION4args {
dir_notification_type4 notification_type;
fattr4 file_attributes;
attr_notice file_attr_notice;
fattr4 dir_attributes;
attr_notice dir_attr_notice;
};
/*
* Notification types.
*/
const DIR_NOTIFICATION_NONE = 0x00000000;
const DIR_NOTIFICATION_CHANGE_FILE_ATTRIBUTES = 0x00000001;
const DIR_NOTIFICATION_CHANGE_DIR_ATTRIBUTES = 0x00000002;
const DIR_NOTIFICATION_REMOVE_ENTRY = 0x00000004;
const DIR_NOTIFICATION_ADD_ENTRY = 0x00000008;
const DIR_NOTIFICATION_RENAME_ENTRY = 0x00000010;
const DIR_NOTIFICATION_CHANGE_COOKIE_VERIFIER = 0x00000020;
typedef uint32_t dir_notification_type4;
RESULT
struct GET_DIR_DELEGATION4resok {
verifier4 cookieverf;
/* Stateid for get_dir_delegation */
stateid4 stateid;
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/* Which notifications can the server support */
dir_notification_type4 supp_notification;
fattr4 file_attributes;
fattr4 dir_attributes;
};
struct attr_notice {
bitmap4 attr_notice_req;
uint32_t attr_notice_delays<>;
};
union GET_DIR_DELEGATION4res switch (nfsstat4 status) {
case NFS4_OK:
/* CURRENT_FH: delegated dir */
GET_DIR_DELEGATION4resok resok4;
default:
void;
};
DESCRIPTION:
The GET_DIR_DELEGATION operation is used by the client to
request a directory delegation. The directory is represented by
the current filehandle. The client also specifies whether it
wants the server to notify it when the directory changes in
certain ways by setting bits in a bitmap. The server may choose
not to grant the delegation. In that case the server will return
NFS4ERR_DIRDELEG_UNAVAIL. If the server decides to hand out the
delegation, it will return a cookie verifier for that directory.
If the cookie verifier changes when the client is holding the
delegation, it will be notified about the change, provided the
client has asked for the notification. Otherwise, the delegation
will be recalled.
The server will also return a directory delegation stateid in
addition to the cookie verifier as a result of the
GET_DIR_DELEGATION operation. This stateid will appear in
callback messages related to the delegation, such as
notifications and delegation recalls. The client will use this
stateid to return the delegation voluntarily or upon recall.
Delegation is returned by calling the DELEGRETURN operation.
The server may not be able to support notifications of certain
events. If the client asks for such notifications, the server
must inform the client of its inability to do so as part of the
GET_DIR_DELEGATION reply.
The GET_DIR_DELEGATION operation can be used for both normal and
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named attribute directories.
IMPLEMENTATION:
Notifications are specified in terms of potential changes to the
directory. A client can ask to be notified whenever an entry is
added to a directory by setting notification_type to
DIR_NOTIFICATION_ADD_ENTRY. It can also ask for notifications on
entry removal, renames, attribute and cookie verifier changes by
setting notification_type flag appropriately . A client can also
ask to be notified of all events that would invalidate its
attribute cache. In that case it will set the notification_type
to D IR_NOTIFICATION_CHANGE_FILE_ATTRIBUTES and
DIR_NOTIFICATION_CHANGE_DIR_ATTRIBUTES. The server will then
noti fy it of any file or directory attribute changes. If a
client is interested in directory entry caching, or negative
name caching, it can set the notification_type appropriately and
the server will notify it of all changes that would otherwise
invalidate its name cache.
The client will set one or more bits in a bitmap to let the
server know what kind of notification(s) it is interested in
getting. For attribute caching the client registers interest in
getting notifications for certain attributes by setting file and
directory attributes in two separate attribute bitmaps. One of
the bitmaps covers directory attributes changes and the other
covers changes to any files in the directory. The server can
choose to support notifications on only a subset of attributes.
The client will also specify the frequency of notifications for
each attribute change by setting the file_attr_notice and
dir_attr_notice arguments. The server will deny the request if
it does not support notifications on that attribute or the
requested frequency. If the client wants notifications for all
changes, it will set the time delay to zero indicating it wants
to be notified as soon as the change occurs. For other types of
notifications, the client does not need to provide the server
with this additional information. So in these cases the
attribute masks for file and directory will not be set.
The server will set a bitmap to inform the client of which
notifications it will receive. If it agrees to send attribute
notifications, it will also set two attribute masks indicating
which attribute change notifications it supports. One of the
masks covers changes in directory attributes and the other
covers changes to any files in the directory.
ERRORS
NFS4ERR_ACCESS
NFS4ERR_BADHANDLE
NFS4ERR_BADCHAR
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NFS4ERR_BADNAME
NFS4ERR_BADXDR
NFS4ERR_FHEXPIRED
NFS4ERR_INVAL
NFS4ERR_MOVED
NFS4ERR_NAMETOOLONG
NFS4ERR_NOENT
NFS4ERR_NOFILEHANDLE
NFS4ERR_NOTDIR
NFS4ERR_RESOURCE
NFS4ERR_SERVERFAULT
NFS4ERR_STALE
NFS4ERR_DIRDELEG_UNAVAIL
NFS4ERR_DIRDELEG_DENIED
5. New Recommended Attributes
#56 - supp_dir_attr_notice - Range of notification delays on
directory attributes
#57 - supp_file_attr_notice - Range of notification delays on file
attributes
DESCRIPTION:
These attributes allow the client and server to negotiate the
frequency of notifications sent due to changes in attributes.
The server returns these attributes for every attribute that it
supports. Each has a range of supported notification delay for
every attribute. If the server does not support notifications on
a certain attribute, it must indicate that by not setting these
attributes.
These attributes are per filesystem attributes. The client need
only get the values when it encounters a new fsid during
navigation of the server's namespace.
The client gets this information when it does a GETATTR on a
directory. The server will return supp_dir_attr_notice on every
directory attribute giving a range of notification frequencies.
It is possible that the server does not support or supports
different ranges for file attributes. The server will set
supp_file_attr_notice to indicate the range of notification
frequencies for file attribute changes. This attribute covers
all files in the directory. e.g. A server can choose to support
notifications for mtime updates between 0 to 5 seconds. If the
client specifies a time delay of 3 seconds, the server will
guarentee that mtime updates are not out of sync by more than 3
seconds. For file changes, the server will provide the same
guarentee for any mtime change on any file in the directory.
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When the client calls the GET_DIR_DELEGATION operation and asks
for attribute change notifications, it will request a
notification time that is within the supported server range. If
the client violates what supp_attr_file_notice or
supp_attr_dir_notice values are, GET_DIR_DELEGATION fails with
NFS4ERR_DIRDELEG_DENIED.
6. New Callback Operation: CB_NOTIFY - Notify directory changes
SYNOPSIS
stateid, notification -> {}
ARGUMENT
struct CB_NOTIFY4args {
stateid4 stateid;
dir_notification4 changes<>;
};
/*
* Notification information sent to the client.
*/
union dir_notification4
switch (dir_notification_type4 notification_type) {
case DIR_NOTIFICATION_CHANGE_FILE_ATTRIBUTE:
dir_notification_attribute4 change_file_attributes;
case DIR_NOTIFICATION_CHANGE_DIR_ATTRIBUTE:
fattr4 change_dir_attributes;
case DIR_NOTIFICATION_REMOVE_ENTRY:
dir_notification_remove4 remove_notification;
case DIR_NOTIFICATION_ADD_ENTRY:
dir_notification_add4 add_notification;
case DIR_NOTIFICATION_RENAME_ENTRY:
dir_notification_rename4 rename_notification;
case DIR_NOTIFICATION_CHANGE_COOKIE_VERIFIER:
dir_notification_verifier4 verf_notification;
};
struct dir_notification_attribute4 {
dir_entry changed_entry;
fattr4 change_dir_attributes;
};
struct dir_notification_remove4 {
dir_entry old_entry;
nfs_cookie4 old_entry_cookie;
};
struct dir_notification_rename4 {
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dir_entry old_entry;
dir_notification_add4 new_entry;
};
struct dir_notification_verifier4 {
verifier4 old_cookieverf;
verifier4 new_cookieverf;
};
struct dir_notification_add4 {
dir_entry new_entry;
/* what READDIR would have returned for this entry */
nfs_cookie4 new_entry_cookie;
bool last_entry;
prev_entry4 prev_entry_info;
};
union prev_entry4 switch (bool isprev) {
case TRUE: /* A previous entry exists */
prev_entry4 prev_entry_info;
case FALSE: /* we are adding to an empty
directory */
void;
};
/*
* Previous entry information
*/
struct prev_entry4 {
dir_entry prev_entry;
/* what READDIR returned for this entry */
nfs_cookie4 prev_entry_cookie;
}
/*
* Changed entry information.
*/
struct dir_entry {
component4 file;
fattr4 attrs;
};
RESULT
struct CB_NOTIFY4res {
nfsstat4 status;
};
DESCRIPTION:
The CB_NOTIFY operation is used by the server to send
notifications to clients about changes in a delegated directory.
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These notifications are sent over the callback path. The
notification is sent once the original request has been
processed on the server. The server will send an array of
notifications for all changes that might have occured in the
directory. It will send the following information for each
operation:
o ADDING A FILE: The server sends information about the new
entry being created along with the cookie for that entry. The
entry information contains the nfs name of the entry and
attributes. If this entry is added to the end of the
directory, the server will set a last_entry flag to true. If
the file is added such that there is atleast one entry before
it, the server will also return the previous entry
information along with its cookie. This is to help clients
find the right location in their DNLC or directory caches
where this entry should be cached.
o REMOVING A FILE: The server sends information about the
directory entry being deleted. The server also sends the
cookie value for the deleted entry so that clients can get to
the cached information for this entry.
o RENAMING A FILE: The server sends information about both the
old entry and the new entry. This includes name and
attributes for each entry. This notification is only sent if
both entries are in the same directory. If the rename is
across directories, the server will send a remove
notification to one directory and an add notification to the
other directory, assuming both have a directory delegation.
o FILE/DIR ATTRIBUTE CHANGE: The client uses the attribute
mask to inform the server of attributes for which it wants to
receive notifications. This change notification can be
requested for both changes to the attributes of the directory
as well as changes to any files in the directory by using two
separate attribute masks. The client can not ask for change
attribute notification per file. One attribute mask covers
all the files in the directory. Upon any attribute change,
the server will send back the values of changed attributes.
If the client asks for change attributes on files, the server
will send back the change notification for both files and
directory. Notifications might not make sense for some
filesystem wide attributes and it is up to the server to
decide which subset it wants to support. The client can
negotiate the frequency of attribute notifications by letting
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the server know how often it wants to be notified of an
attribute change. The server will return a range of supported
notification frequencies or an indication that no
notification is permitted for every attribute by setting the
supp_attr_file_notice and supp_attr_dir_notice attributes.
o COOKIE VERIFIER CHANGE: If the cookie verifier changes while
a client is holding a delegation, the server will notify the
client so that it can invalidate its cookies and reissue a
READDIR to get the new set of cookies.
ERRORS
NFS4ERR_BAD_STATEID
NFS4ERR_INVAL
NFS4ERR_BADXDR
7. Delegation Recall
The server will recall the directory delegation by sending a callback
to the client. It will use the same callback procedure as used for
recalling file delegations. The server will recall the delegation
when the directory changes in a way that is not covered by the
notification. Also if the server notices that handing out a
delegation for a directory is causing too many notifications to be
sent out, it may decide not to hand out a delegation for that
directory. If another client tries to remove the directory for which
a delegation has been granted, the server may recall the delegation.
The server will recall the delegation by sending a CB_RECALL callback
to the client and if the delegation is being recalled due to a change
being made to the directory that is not covered by the notification,
the request making that change may need to wait while the client
returns the delegation.
8. New Callback Operation: CB_RECALL_ANY - Keep any N delegations
SYNOPSIS
N -> {}
ARGUMENT
struct CB_RECALLANYY4args {
uint4 dlgs_to_keep;
}
RESULT
struct CB_RECALLANY4res {
nfsstat4 status;
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};
DESCRIPTION:
The server may decide that it can not hold all the delegation
state without running out of resources. Since the server has no
knowledge of which delegations are being used more than others,
it can not implement an effective reclaim scheme that avoids
reclaiming frequently used delegations. In that case the server
may issue a CB_RECALL_ANY callback to the client asking it to
keep N delegations and return the rest. The reason why
CB_RECALL_ANY specifies a count of delegations the client may
keep as opposed to a count of delegations the client must yield
is as follows. Were it otherwise, there is a potential for a
race between a CB_RECALL_ANY that had a count of delegations to
free with a set of client originated operations to return
delegations. As a result of the race the client and server would
have differing ideas as to how many delegations to return. Hence
the client could mistakenly free too many delegations.
The client can choose to return any type of delegation as a
result of this callback i.e. read, write or directory
delegation. The client can also choose to keep more delegations
than what the server asked for and it is up to the server to
handle this situation. The server must give the client enough
time to return the delegations. This time should not be less
than the lease period.
ERRORS
NFS4ERR_RESOURCE
9. Delegation Recovery
Since the mode of notifications proposed in this draft is
asynchronous in nature, and since the primary use of directory
delegations is anticipated to be in the conjection with
notifications, adding reclaim functionality will add unnecessary
implementation complexity. Thus, the client is required to establish
a new delegation on a server or client reboot.
10. Issues
10.1. Synchronous vs. Asynchronous notifications
An async notification would be sent to a client holding the
delegation after a directory changing event has taken place. It is
possible that the client holding the delegation tries to act on the
change before it has been notified by the server and fails. It would
certainly be better if the notification was synchronous so that when
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the client tried to access, e.g. a newly created file, it was
guaranteed to be there.
For one form of synchronous notification, the server would suspend
the request and send a notification to the client notifying it of the
change about to occur. However this is not a true synchronous
notification, since after the server has sent out the notification,
it might discover that due to some error the request cannot be
completed. If this is for a regular file create, the client might add
this information to its directory cache and return bogus positive
information as a result of a readdir call. This puts the client in a
worse situation than with async notifications where the change is
guaranteed to be available but a delay may be involved.
For another form of synchronous notification, the server would notify
a client holding the delegation about a change about to occur in a
directory, only after the server has determined that this request is
definitely going to succeed. At that time, the server would send a
notification to the client holding the delegation while suspending
the original request. However note that the server has not yet
committed the change so at this point in time, only the client
holding the delegation knows about this change. Once the client
acknowledges the notification, the server will commit the change
making it visible to all other clients. It is doubtful many operating
environments would allow a server to provide this form of
notification.
Since synchronous notifications do not guarentee true request
ordering any better than asynchronous notifications except by adding
substantial implementation complexity, asynchronous notifications are
proposed as the default method for notifying the client. These
notifications l be sent after the directory changing operation has
completed.
11. RPC Definition File Changes
/*
* Copyright (C) The Internet Society (2003)
* All Rights Reserved.
*/
/*
* nfs41_prot.x
*/
%/* $Id: nfs41_prot.x,v 1.1 2004/02/01 05:10:53 saadia Exp $ */
/* new operation, GET_DIR_DELEGATION */
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/*
* Notification mask for letting the server know which notifications
* the client is interested in.
*/
typedef uint32_t dir_notification_type4;
/*
* The bitmask constants used for notification_type field
*/
const DIR_NOTIFICATION_NONE = 0x00000000;
const DIR_NOTIFICATION_CHANGE_FILE_ATTRIBUTES = 0x00000001;
const DIR_NOTIFICATION_CHANGE_DIR_ATTRIBUTES = 0x00000002;
const DIR_NOTIFICATION_REMOVE_ENTRY = 0x00000004;
const DIR_NOTIFICATION_ADD_ENTRY = 0x00000008;
const DIR_NOTIFICATION_RENAME_ENTRY = 0x00000010;
const DIR_NOTIFICATION_CHANGE_COOKIE_VERIFIER = 0x00000020;
/*
* Input arguments passed to the GET_DIR_DELEGATION operation.
*/
struct GET_DIR_DELEGATION4args {
/* CURRENT_FH: directory */
dir_notification_type4 notification_type;
fattr4 file_attributes;
attr_notice file_attr_notice;
fattr4 dir_attributes;
attr_notice dir_attr_notice;
};
/*
* Result flags
*/
struct GET_DIR_DELEGATION4resok {
verifier4 cookieverf;
/* Stateid for get_dir_delegation */
stateid4 stateid;
/* Which notifications can the server support */
dir_notification_type4 supp_notification;
/* Which attribute notifications can the server support */
fattr4 file_attributes;
fattr4 dir_attributes;
};
struct attr_notice {
bitmap4 attr_notice_req;
uint32_t attr_notice_delays<>;
};
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union GET_DIR_DELEGATION4res switch (nfsstat4 status) {
case NFS4_OK:
/* CURRENT_FH: delegated dir */
GET_DIR_DELEGATION4resok resok4;
default:
void;
};
/*
* Operation arrays
*/
enum nfs_opnum4 {
OP_ACCESS = 3,
OP_CLOSE = 4,
OP_COMMIT = 5,
OP_CREATE = 6,
OP_DELEGPURGE = 7,
OP_DELEGRETURN = 8,
OP_GETATTR = 9,
OP_GETFH = 10,
OP_LINK = 11,
OP_LOCK = 12,
OP_LOCKT = 13,
OP_LOCKU = 14,
OP_LOOKUP = 15,
OP_LOOKUPP = 16,
OP_NVERIFY = 17,
OP_OPEN = 18,
OP_OPENATTR = 19,
OP_OPEN_CONFIRM = 20,
OP_OPEN_DOWNGRADE = 21,
OP_PUTFH = 22,
OP_PUTPUBFH = 23,
OP_PUTROOTFH = 24,
OP_READ = 25,
OP_READDIR = 26,
OP_READLINK = 27,
OP_REMOVE = 28,
OP_RENAME = 29,
OP_RENEW = 30,
OP_RESTOREFH = 31,
OP_SAVEFH = 32,
OP_SECINFO = 33,
OP_SETATTR = 34,
OP_SETCLIENTID = 35,
OP_SETCLIENTID_CONFIRM = 36,
OP_VERIFY = 37,
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OP_WRITE = 38,
OP_RELEASE_LOCKOWNER = 39,
OP_OPENDIR = 40,
OP_ILLEGAL = 10044
};
union nfs_argop4 switch (nfs_opnum4 argop) {
case OP_ACCESS: ACCESS4args opaccess;
case OP_CLOSE: CLOSE4args opclose;
case OP_COMMIT: COMMIT4args opcommit;
case OP_CREATE: CREATE4args opcreate;
case OP_DELEGPURGE: DELEGPURGE4args opdelegpurge;
case OP_DELEGRETURN: DELEGRETURN4args opdelegreturn;
case OP_GETATTR: GETATTR4args opgetattr;
case OP_GETFH: void;
case OP_LINK: LINK4args oplink;
case OP_LOCK: LOCK4args oplock;
case OP_LOCKT: LOCKT4args oplockt;
case OP_LOCKU: LOCKU4args oplocku;
case OP_LOOKUP: LOOKUP4args oplookup;
case OP_LOOKUPP: void;
case OP_NVERIFY: NVERIFY4args opnverify;
case OP_OPEN: OPEN4args opopen;
case OP_OPENATTR: OPENATTR4args opopenattr;
case OP_OPEN_CONFIRM: OPEN_CONFIRM4args opopen_confirm;
case OP_OPEN_DOWNGRADE: OPEN_DOWNGRADE4args opopen_downgrade;
case OP_PUTFH: PUTFH4args opputfh;
case OP_PUTPUBFH: void;
case OP_PUTROOTFH: void;
case OP_READ: READ4args opread;
case OP_READDIR: READDIR4args opreaddir;
case OP_READLINK: void;
case OP_REMOVE: REMOVE4args opremove;
case OP_RENAME: RENAME4args oprename;
case OP_RENEW: RENEW4args oprenew;
case OP_RESTOREFH: void;
case OP_SAVEFH: void;
case OP_SECINFO: SECINFO4args opsecinfo;
case OP_SETATTR: SETATTR4args opsetattr;
case OP_SETCLIENTID: SETCLIENTID4args opsetclientid;
case OP_SETCLIENTID_CONFIRM: SETCLIENTID_CONFIRM4args
opsetclientid_confirm;
case OP_VERIFY: VERIFY4args opverify;
case OP_WRITE: WRITE4args opwrite;
case OP_RELEASE_LOCKOWNER: RELEASE_LOCKOWNER4args
oprelease_lockowner;
case OP_OPENDIR: OPENDIR4args opopendir;
case OP_ILLEGAL: void;
};
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union nfs_resop4 switch (nfs_opnum4 resop){
case OP_ACCESS: ACCESS4res opaccess;
case OP_CLOSE: CLOSE4res opclose;
case OP_COMMIT: COMMIT4res opcommit;
case OP_CREATE: CREATE4res opcreate;
case OP_DELEGPURGE: DELEGPURGE4res opdelegpurge;
case OP_DELEGRETURN: DELEGRETURN4res opdelegreturn;
case OP_GETATTR: GETATTR4res opgetattr;
case OP_GETFH: GETFH4res opgetfh;
case OP_LINK: LINK4res oplink;
case OP_LOCK: LOCK4res oplock;
case OP_LOCKT: LOCKT4res oplockt;
case OP_LOCKU: LOCKU4res oplocku;
case OP_LOOKUP: LOOKUP4res oplookup;
case OP_LOOKUPP: LOOKUPP4res oplookupp;
case OP_NVERIFY: NVERIFY4res opnverify;
case OP_OPEN: OPEN4res opopen;
case OP_OPENATTR: OPENATTR4res opopenattr;
case OP_OPEN_CONFIRM: OPEN_CONFIRM4res opopen_confirm;
case OP_OPEN_DOWNGRADE: OPEN_DOWNGRADE4res opopen_downgrade;
case OP_PUTFH: PUTFH4res opputfh;
case OP_PUTPUBFH: PUTPUBFH4res opputpubfh;
case OP_PUTROOTFH: PUTROOTFH4res opputrootfh;
case OP_READ: READ4res opread;
case OP_READDIR: READDIR4res opreaddir;
case OP_READLINK: READLINK4res opreadlink;
case OP_REMOVE: REMOVE4res opremove;
case OP_RENAME: RENAME4res oprename;
case OP_RENEW: RENEW4res oprenew;
case OP_RESTOREFH: RESTOREFH4res oprestorefh;
case OP_SAVEFH: SAVEFH4res opsavefh;
case OP_SECINFO: SECINFO4res opsecinfo;
case OP_SETATTR: SETATTR4res opsetattr;
case OP_SETCLIENTID: SETCLIENTID4res opsetclientid;
case OP_SETCLIENTID_CONFIRM: SETCLIENTID_CONFIRM4res
opsetclientid_confirm;
case OP_VERIFY: VERIFY4res opverify;
case OP_WRITE: WRITE4res opwrite;
case OP_RELEASE_LOCKOWNER: RELEASE_LOCKOWNER4res
oprelease_lockowner;
case OP_OPENDIR: OPENDIR4res opopendir;
case OP_ILLEGAL: ILLEGAL4res opillegal;
};
struct COMPOUND4args {
utf8str_cs tag;
uint32_t minorversion; /* == 1 !!! */
nfs_argop4 argarray<>;
};
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struct COMPOUND4res {
nfsstat4 status;
utf8str_cs tag;
nfs_resop4 resarray<>;
};
/*
* New error codes
*/
enum nfsstat4 {
NFS4_OK = 0, /* everything is okay */
NFS4ERR_PERM = 1, /* caller not privileged */
NFS4ERR_NOENT = 2, /* no such file/directory */
NFS4ERR_IO = 5, /* hard I/O error */
NFS4ERR_NXIO = 6, /* no such device */
NFS4ERR_ACCESS = 13, /* access denied */
NFS4ERR_EXIST = 17, /* file already exists */
NFS4ERR_XDEV = 18, /* different filesystems */
/* Unused/reserved 19 */
NFS4ERR_NOTDIR = 20, /* should be a directory */
NFS4ERR_ISDIR = 21, /* should not be directory */
NFS4ERR_INVAL = 22, /* invalid argument */
NFS4ERR_FBIG = 27, /* file exceeds server max */
NFS4ERR_NOSPC = 28, /* no space on filesystem */
NFS4ERR_ROFS = 30, /* read-only filesystem */
NFS4ERR_MLINK = 31, /* too many hard links */
NFS4ERR_NAMETOOLONG = 63, /* name exceeds server max */
NFS4ERR_NOTEMPTY = 66, /* directory not empty */
NFS4ERR_DQUOT = 69, /* hard quota limit reached*/
NFS4ERR_STALE = 70, /* file no longer exists */
NFS4ERR_BADHANDLE = 10001,/* Illegal filehandle */
NFS4ERR_BAD_COOKIE = 10003,/* READDIR cookie is stale */
NFS4ERR_NOTSUPP = 10004,/* operation not supported */
NFS4ERR_TOOSMALL = 10005,/* response limit exceeded */
NFS4ERR_SERVERFAULT = 10006,/* undefined server error */
NFS4ERR_BADTYPE = 10007,/* type invalid for CREATE */
NFS4ERR_DELAY = 10008,/* file "busy" - retry */
NFS4ERR_SAME = 10009,/* nverify says attrs same */
NFS4ERR_DENIED = 10010,/* lock unavailable */
NFS4ERR_EXPIRED = 10011,/* lock lease expired */
NFS4ERR_LOCKED = 10012,/* I/O failed due to lock */
NFS4ERR_GRACE = 10013,/* in grace period */
NFS4ERR_FHEXPIRED = 10014,/* filehandle expired */
NFS4ERR_SHARE_DENIED = 10015,/* share reserve denied */
NFS4ERR_WRONGSEC = 10016,/* wrong security flavor */
NFS4ERR_CLID_INUSE = 10017,/* clientid in use */
NFS4ERR_RESOURCE = 10018,/* resource exhaustion */
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NFS4ERR_MOVED = 10019,/* filesystem relocated */
NFS4ERR_NOFILEHANDLE = 10020,/* current FH is not set */
NFS4ERR_MINOR_VERS_MISMATCH = 10021,/* minor vers not supp */
NFS4ERR_STALE_CLIENTID = 10022,/* server has rebooted */
NFS4ERR_STALE_STATEID = 10023,/* server has rebooted */
NFS4ERR_OLD_STATEID = 10024,/* state is out of sync */
NFS4ERR_BAD_STATEID = 10025,/* incorrect stateid */
NFS4ERR_BAD_SEQID = 10026,/* request is out of seq. */
NFS4ERR_NOT_SAME = 10027,/* verify - attrs not same */
NFS4ERR_LOCK_RANGE = 10028,/* lock range not supported*/
NFS4ERR_SYMLINK = 10029,/* should be file/directory*/
NFS4ERR_RESTOREFH = 10030,/* no saved filehandle */
NFS4ERR_LEASE_MOVED = 10031,/* some filesystem moved */
NFS4ERR_ATTRNOTSUPP = 10032,/* recommended attr not sup*/
NFS4ERR_NO_GRACE = 10033,/* reclaim outside of grace*/
NFS4ERR_RECLAIM_BAD = 10034,/* reclaim error at server */
NFS4ERR_RECLAIM_CONFLICT = 10035,/* conflict on reclaim */
NFS4ERR_BADXDR = 10036,/* XDR decode failed */
NFS4ERR_LOCKS_HELD = 10037,/* file locks held at CLOSE*/
NFS4ERR_OPENMODE = 10038,/* conflict in OPEN and I/O*/
NFS4ERR_BADOWNER = 10039,/* owner translation bad */
NFS4ERR_BADCHAR = 10040,/* utf-8 char not supported*/
NFS4ERR_BADNAME = 10041,/* name not supported */
NFS4ERR_BAD_RANGE = 10042,/* lock range not supported*/
NFS4ERR_LOCK_NOTSUPP = 10043,/* no atomic up/downgrade */
NFS4ERR_OP_ILLEGAL = 10044,/* undefined operation */
NFS4ERR_DEADLOCK = 10045,/* file locking deadlock */
NFS4ERR_FILE_OPEN = 10046,/* open file blocks op. */
NFS4ERR_ADMIN_REVOKED = 10047,/* lockowner state revoked */
NFS4ERR_CB_PATH_DOWN = 10048,/* callback path down */
NFS4ERR_DIRDELEG_UNAVAIL= 10049,/* dir dlg. not returned */
NFS4ERR_DIRDELEG_DENIED = 10050 /* dir delegation denied */
};
/*
* New Callback operation CB_NOTIFY
*/
struct CB_NOTIFY4args {
stateid4 stateid;
dir_notification4 changes<>;
};
/*
* Changed entry information.
*/
struct dir_entry {
component4 file;
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fattr4 attrs;
};
struct dir_notification_attribute4 {
dir_entry changed_entry;
fattr change_dir_attributes;
};
struct dir_notification_remove4 {
dir_entry old_entry;
nfs_cookie4 old_entry_cookie;
};
struct dir_notification_rename4 {
dir_entry old_entry;
dir_notification_add4 new_entry;
};
struct dir_notification_verifier4 {
verifier4 old_cookieverf;
verifier4 new_cookieverf;
};
struct dir_notification_add4 {
dir_entry new_entry;
nfs_cookie4 new_entry_cookie; /* what READDIR would
have returned
for this entry */
bool last_entry;
prev_entry4 prev_entry_info;
};
union prev_entry4 switch (bool isprev) {
case TRUE:
prev_entry4 prev_entry_info;
case FALSE: /* we are adding to an empty directory */
void;
};
/*
* Previous entry information
*/
struct prev_entry4 {
dir_entry prev_entry;
/* what READDIR returned for this entry */
nfs_cookie4 prev_entry_cookie;
};
/*
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* Notification information sent to the client.
*/
union dir_notification4
switch (dir_notification_type4 notification_type) {
case DIR_NOTIFICATION_CHANGE_FILE_ATTRIBUTE:
dir_notification_attribute4 change_file_attributes;
case DIR_NOTIFICATION_CHANGE_DIR_ATTRIBUTE:
fattr4 change_dir_attributes;
case DIR_NOTIFICATION_REMOVE_ENTRY:
dir_notification_remove4 remove_notification;
case DIR_NOTIFICATION_ADD_ENTRY:
dir_notification_add4 add_notification;
case DIR_NOTIFICATION_RENAME_ENTRY:
dir_notification_rename4 rename_notification;
case DIR_NOTIFICATION_CHANGE_COOKIE_VERIFIER:
dir_notification_verifier4 verf_notification;
};
struct CB_NOTIFY4res {
nfsstat4 status;
};
/*
* New Callback operation CB_RECALL_ANY
*
struct CB_RECALLANYY4args {
uint4 dlgs_to_keep;
}
struct CB_RECALLANY4res {
nfsstat4 status;
};
/*
* Various definitions for CB_COMPOUND
*/
enum nfs_cb_opnum4 {
OP_CB_GETATTR = 3,
OP_CB_RECALL = 4,
OP_CB_NOTIFY = 5,
OP_CB_RECALL_ANY = 6,
OP_CB_ILLEGAL = 10044
};
union nfs_cb_argop4 switch (unsigned argop) {
case OP_CB_GETATTR: CB_GETATTR4args opcbgetattr;
case OP_CB_RECALL: CB_RECALL4args opcbrecall;
case OP_CB_NOTIFY: CB_NOTIFY4args opcbnotify;
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case OP_CB_RECALLANY: CB_RECALLANY4args opcbrecallany;
case OP_CB_ILLEGAL: CB_ILLEGAL4args opcbillegal;
};
union nfs_cb_resop4 switch (unsigned resop) {
case OP_CB_GETATTR: CB_GETATTR4res opcbgetattr;
case OP_CB_RECALL: CB_RECALL4res opcbrecall;
case OP_CB_NOTIFY: CB_NOTIFY4res opcbnotify;
case OP_CB_RECALLANY: CB_RECALLANY4res opcbrecallany;
case OP_CB_ILLEGAL: CB_ILLEGAL4res opcbillegal;
};
struct CB_COMPOUND4args {
utf8str_cs tag;
uint32_t minorversion;
uint32_t callback_ident;
nfs_cb_argop4 argarray<>;
};
struct CB_COMPOUND4res {
nfsstat4 status;
utf8str_cs tag;
nfs_cb_resop4 resarray<>;
};
12. IANA Considerations
The IANA considerations of NFSv4.0 apply to NFSv4.1.
13. Acknowledgements
David Noveck and Michael Eisler for their constructive feedback and
critical comments.
14. Normative References
[RFC3530]
S. Shepler, B. Callaghan, D. Robinson, R. Thurlow, C. Beame, M.
Eisler, D. Noveck, "NFS version 4 Protocol", RFC 3530, April,
2003.
[talpey]
T. Talpey, S. Shepler, "NFSv4 RDMA and Session Extensions",
Internet-Draft, May, 2003. A URL for this Internet-Draft is
available at http://www.ietf.org/internet-drafts/draft-talpey-
nfsv4-rdma-sess-00.txt
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15. Informative References
None.
16. Author's Address
Saadia Khan
2324 Dubois Street
Milpitas, CA 95035
USA
Phone: 408-957-9626
EMail: saadiak@yahoo.com
17. IPR Notices
The IETF takes no position regarding the validity or scope of any
intellectual property or other rights that might be claimed to
pertain to the implementation or use of the technology described in
this document or the extent to which any license under such rights
might or might not be available; neither does it represent that it
has made any effort to identify any such rights. Information on the
IETF's procedures with respect to rights in standards-track and
standards-related documentation can be found in BCP-11. Copies of
claims of rights made available for publication and any assurances of
licenses to be made available, or the result of an attempt made to
obtain a general license or permission for the use of such
proprietary rights by implementors or users of this specification can
be obtained from the IETF Secretariat.
The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary
rights which may cover technology that may be required to practice
this standard. Please address the information to the IETF Executive
Director.
18. Copyright Notice
Copyright (C) The Internet Society (2003). All Rights Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
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developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English.
The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns.
This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
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