diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2020-03-30 12:45:23 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-03-30 12:45:23 -0700 |
commit | 481ed297d900af0ce395f6ca8975903b76a5a59e (patch) | |
tree | e3862e9993cd8e2245c5a6d632f45dd3f77d1d62 /Documentation/filesystems/nfs | |
parent | e59cd88028dbd41472453e5883f78330aa73c56e (diff) | |
parent | abcb1e021ae5a36374c635eeaba5cec733169b78 (diff) |
Merge tag 'docs-5.7' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
"This has been a busy cycle for documentation work.
Highlights include:
- Lots of RST conversion work by Mauro, Daniel ALmeida, and others.
Maybe someday we'll get to the end of this stuff...maybe...
- Some organizational work to bring some order to the core-api
manual.
- Various new docs and additions to the existing documentation.
- Typo fixes, warning fixes, ..."
* tag 'docs-5.7' of git://git.lwn.net/linux: (123 commits)
Documentation: x86: exception-tables: document CONFIG_BUILDTIME_TABLE_SORT
MAINTAINERS: adjust to filesystem doc ReST conversion
docs: deprecated.rst: Add BUG()-family
doc: zh_CN: add translation for virtiofs
doc: zh_CN: index files in filesystems subdirectory
docs: locking: Drop :c:func: throughout
docs: locking: Add 'need' to hardirq section
docs: conf.py: avoid thousands of duplicate label warning on Sphinx
docs: prevent warnings due to autosectionlabel
docs: fix reference to core-api/namespaces.rst
docs: fix pointers to io-mapping.rst and io_ordering.rst files
Documentation: Better document the softlockup_panic sysctl
docs: hw-vuln: tsx_async_abort.rst: get rid of an unused ref
docs: perf: imx-ddr.rst: get rid of a warning
docs: filesystems: fuse.rst: supress a Sphinx warning
docs: translations: it: avoid duplicate refs at programming-language.rst
docs: driver.rst: supress two ReSt warnings
docs: trace: events.rst: convert some new stuff to ReST format
Documentation: Add io_ordering.rst to driver-api manual
Documentation: Add io-mapping.rst to driver-api manual
...
Diffstat (limited to 'Documentation/filesystems/nfs')
-rw-r--r-- | Documentation/filesystems/nfs/index.rst | 13 | ||||
-rw-r--r-- | Documentation/filesystems/nfs/knfsd-stats.rst (renamed from Documentation/filesystems/nfs/knfsd-stats.txt) | 17 | ||||
-rw-r--r-- | Documentation/filesystems/nfs/nfs41-server.rst | 256 | ||||
-rw-r--r-- | Documentation/filesystems/nfs/nfs41-server.txt | 173 | ||||
-rw-r--r-- | Documentation/filesystems/nfs/pnfs.rst (renamed from Documentation/filesystems/nfs/pnfs.txt) | 25 | ||||
-rw-r--r-- | Documentation/filesystems/nfs/rpc-cache.rst (renamed from Documentation/filesystems/nfs/rpc-cache.txt) | 136 | ||||
-rw-r--r-- | Documentation/filesystems/nfs/rpc-server-gss.rst (renamed from Documentation/filesystems/nfs/rpc-server-gss.txt) | 19 |
7 files changed, 380 insertions, 259 deletions
diff --git a/Documentation/filesystems/nfs/index.rst b/Documentation/filesystems/nfs/index.rst new file mode 100644 index 000000000000..65805624e39b --- /dev/null +++ b/Documentation/filesystems/nfs/index.rst @@ -0,0 +1,13 @@ +=============================== +NFS +=============================== + + +.. toctree:: + :maxdepth: 1 + + pnfs + rpc-cache + rpc-server-gss + nfs41-server + knfsd-stats diff --git a/Documentation/filesystems/nfs/knfsd-stats.txt b/Documentation/filesystems/nfs/knfsd-stats.rst index 1a5d82180b84..80bcf13550de 100644 --- a/Documentation/filesystems/nfs/knfsd-stats.txt +++ b/Documentation/filesystems/nfs/knfsd-stats.rst @@ -1,7 +1,9 @@ - +============================ Kernel NFS Server Statistics ============================ +:Authors: Greg Banks <gnb@sgi.com> - 26 Mar 2009 + This document describes the format and semantics of the statistics which the kernel NFS server makes available to userspace. These statistics are available in several text form pseudo files, each of @@ -18,7 +20,7 @@ by parsing routines. All other lines contain a sequence of fields separated by whitespace. /proc/fs/nfsd/pool_stats ------------------------- +======================== This file is available in kernels from 2.6.30 onwards, if the /proc/fs/nfsd filesystem is mounted (it almost always should be). @@ -109,15 +111,12 @@ this case), or the transport can be enqueued for later attention (sockets-enqueued counts this case), or the packet can be temporarily deferred because the transport is currently being used by an nfsd thread. This last case is not very interesting and is not explicitly -counted, but can be inferred from the other counters thus: +counted, but can be inferred from the other counters thus:: -packets-deferred = packets-arrived - ( sockets-enqueued + threads-woken ) + packets-deferred = packets-arrived - ( sockets-enqueued + threads-woken ) More ----- -Descriptions of the other statistics file should go here. - +==== -Greg Banks <gnb@sgi.com> -26 Mar 2009 +Descriptions of the other statistics file should go here. diff --git a/Documentation/filesystems/nfs/nfs41-server.rst b/Documentation/filesystems/nfs/nfs41-server.rst new file mode 100644 index 000000000000..16b5f02f81c3 --- /dev/null +++ b/Documentation/filesystems/nfs/nfs41-server.rst @@ -0,0 +1,256 @@ +============================= +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. diff --git a/Documentation/filesystems/nfs/nfs41-server.txt b/Documentation/filesystems/nfs/nfs41-server.txt deleted file mode 100644 index 682a59fabe3f..000000000000 --- a/Documentation/filesystems/nfs/nfs41-server.txt +++ /dev/null @@ -1,173 +0,0 @@ -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 - - +----------------------+------------+--------------+----------------+ - | Operation | REQ, REC, | Feature | Definition | - | | OPT, or | (REQ, REC, | | - | | MNI | or OPT) | | - +----------------------+------------+--------------+----------------+ - | 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 - - +-------------------------+-----------+-------------+---------------+ - | Operation | REQ, REC, | Feature | Definition | - | | OPT, or | (REQ, REC, | | - | | MNI | or OPT) | | - +-------------------------+-----------+-------------+---------------+ - | 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. diff --git a/Documentation/filesystems/nfs/pnfs.txt b/Documentation/filesystems/nfs/pnfs.rst index 80dc0bdc302a..7c470ecdc3a9 100644 --- a/Documentation/filesystems/nfs/pnfs.txt +++ b/Documentation/filesystems/nfs/pnfs.rst @@ -1,15 +1,17 @@ -Reference counting in pnfs: +========================== +Reference counting in pnfs ========================== The are several inter-related caches. We have layouts which can reference multiple devices, each of which can reference multiple data servers. Each data server can be referenced by multiple devices. Each device -can be referenced by multiple layouts. To keep all of this straight, +can be referenced by multiple layouts. To keep all of this straight, we need to reference count. struct pnfs_layout_hdr ----------------------- +====================== + The on-the-wire command LAYOUTGET corresponds to struct pnfs_layout_segment, usually referred to by the variable name lseg. Each nfs_inode may hold a pointer to a cache of these layout @@ -25,7 +27,8 @@ the reference count, as the layout is kept around by the lseg that keeps it in the list. deviceid_cache --------------- +============== + lsegs reference device ids, which are resolved per nfs_client and layout driver type. The device ids are held in a RCU cache (struct nfs4_deviceid_cache). The cache itself is referenced across each @@ -38,24 +41,26 @@ justification, but seems reasonable given that we can have multiple deviceid's per filesystem, and multiple filesystems per nfs_client. The hash code is copied from the nfsd code base. A discussion of -hashing and variations of this algorithm can be found at: -http://groups.google.com/group/comp.lang.c/browse_thread/thread/9522965e2b8d3809 +hashing and variations of this algorithm can be found `here. +<http://groups.google.com/group/comp.lang.c/browse_thread/thread/9522965e2b8d3809>`_ data server cache ------------------ +================= + file driver devices refer to data servers, which are kept in a module level cache. Its reference is held over the lifetime of the deviceid pointing to it. lseg ----- +==== + lseg maintains an extra reference corresponding to the NFS_LSEG_VALID bit which holds it in the pnfs_layout_hdr's list. When the final lseg is removed from the pnfs_layout_hdr's list, the NFS_LAYOUT_DESTROYED bit is set, preventing any new lsegs from being added. layout drivers --------------- +============== PNFS utilizes what is called layout drivers. The STD defines 4 basic layout types: "files", "objects", "blocks", and "flexfiles". For each @@ -68,6 +73,6 @@ Blocks-layout-driver code is in: fs/nfs/blocklayout/.. directory Flexfiles-layout-driver code is in: fs/nfs/flexfilelayout/.. directory blocks-layout setup -------------------- +=================== TODO: Document the setup needs of the blocks layout driver diff --git a/Documentation/filesystems/nfs/rpc-cache.txt b/Documentation/filesystems/nfs/rpc-cache.rst index c4dac829db0f..bb164eea969b 100644 --- a/Documentation/filesystems/nfs/rpc-cache.txt +++ b/Documentation/filesystems/nfs/rpc-cache.rst @@ -1,9 +1,14 @@ - This document gives a brief introduction to the caching +========= +RPC Cache +========= + +This document gives a brief introduction to the caching mechanisms in the sunrpc layer that is used, in particular, for NFS authentication. -CACHES +Caches ====== + The caching replaces the old exports table and allows for a wide variety of values to be caches. @@ -12,6 +17,7 @@ quite possibly very different in content and use. There is a corpus of common code for managing these caches. Examples of caches that are likely to be needed are: + - mapping from IP address to client name - mapping from client name and filesystem to export options - mapping from UID to list of GIDs, to work around NFS's limitation @@ -21,6 +27,7 @@ Examples of caches that are likely to be needed are: - mapping from network identify to public key for crypto authentication. The common code handles such things as: + - general cache lookup with correct locking - supporting 'NEGATIVE' as well as positive entries - allowing an EXPIRED time on cache items, and removing @@ -35,60 +42,66 @@ The common code handles such things as: Creating a Cache ---------------- -1/ A cache needs a datum to store. This is in the form of a - structure definition that must contain a |