aboutsummaryrefslogtreecommitdiffstats
path: root/Documentation/filesystems
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/filesystems')
-rw-r--r--Documentation/filesystems/9p.txt40
-rw-r--r--Documentation/filesystems/caching/fscache.txt110
-rw-r--r--Documentation/filesystems/caching/netfs-api.txt21
-rw-r--r--Documentation/filesystems/ext3.txt16
-rw-r--r--Documentation/filesystems/ext4.txt21
-rw-r--r--Documentation/filesystems/ncpfs.txt6
-rw-r--r--Documentation/filesystems/nfs41-server.txt54
-rw-r--r--Documentation/filesystems/nfsroot.txt2
-rw-r--r--Documentation/filesystems/ocfs2.txt6
-rw-r--r--Documentation/filesystems/proc.txt28
-rw-r--r--Documentation/filesystems/sharedsubtree.txt220
-rw-r--r--Documentation/filesystems/vfat.txt2
-rw-r--r--Documentation/filesystems/vfs.txt7
13 files changed, 318 insertions, 215 deletions
diff --git a/Documentation/filesystems/9p.txt b/Documentation/filesystems/9p.txt
index 6208f55c44c3..57e0b80a5274 100644
--- a/Documentation/filesystems/9p.txt
+++ b/Documentation/filesystems/9p.txt
@@ -18,11 +18,11 @@ the 9p client is available in the form of a USENIX paper:
18 18
19Other applications are described in the following papers: 19Other applications are described in the following papers:
20 * XCPU & Clustering 20 * XCPU & Clustering
21 http://www.xcpu.org/xcpu-talk.pdf 21 http://xcpu.org/papers/xcpu-talk.pdf
22 * KVMFS: control file system for KVM 22 * KVMFS: control file system for KVM
23 http://www.xcpu.org/kvmfs.pdf 23 http://xcpu.org/papers/kvmfs.pdf
24 * CellFS: A New ProgrammingModel for the Cell BE 24 * CellFS: A New Programming Model for the Cell BE
25 http://www.xcpu.org/cellfs-talk.pdf 25 http://xcpu.org/papers/cellfs-talk.pdf
26 * PROSE I/O: Using 9p to enable Application Partitions 26 * PROSE I/O: Using 9p to enable Application Partitions
27 http://plan9.escet.urjc.es/iwp9/cready/PROSE_iwp9_2006.pdf 27 http://plan9.escet.urjc.es/iwp9/cready/PROSE_iwp9_2006.pdf
28 28
@@ -48,6 +48,7 @@ OPTIONS
48 (see rfdno and wfdno) 48 (see rfdno and wfdno)
49 virtio - connect to the next virtio channel available 49 virtio - connect to the next virtio channel available
50 (from lguest or KVM with trans_virtio module) 50 (from lguest or KVM with trans_virtio module)
51 rdma - connect to a specified RDMA channel
51 52
52 uname=name user name to attempt mount as on the remote server. The 53 uname=name user name to attempt mount as on the remote server. The
53 server may override or ignore this value. Certain user 54 server may override or ignore this value. Certain user
@@ -59,16 +60,22 @@ OPTIONS
59 cache=mode specifies a caching policy. By default, no caches are used. 60 cache=mode specifies a caching policy. By default, no caches are used.
60 loose = no attempts are made at consistency, 61 loose = no attempts are made at consistency,
61 intended for exclusive, read-only mounts 62 intended for exclusive, read-only mounts
63 fscache = use FS-Cache for a persistent, read-only
64 cache backend.
62 65
63 debug=n specifies debug level. The debug level is a bitmask. 66 debug=n specifies debug level. The debug level is a bitmask.
64 0x01 = display verbose error messages 67 0x01 = display verbose error messages
65 0x02 = developer debug (DEBUG_CURRENT) 68 0x02 = developer debug (DEBUG_CURRENT)
66 0x04 = display 9p trace 69 0x04 = display 9p trace
67 0x08 = display VFS trace 70 0x08 = display VFS trace
68 0x10 = display Marshalling debug 71 0x10 = display Marshalling debug
69 0x20 = display RPC debug 72 0x20 = display RPC debug
70 0x40 = display transport debug 73 0x40 = display transport debug
71 0x80 = display allocation debug 74 0x80 = display allocation debug
75 0x100 = display protocol message debug
76 0x200 = display Fid debug
77 0x400 = display packet debug
78 0x800 = display fscache tracing debug
72 79
73 rfdno=n the file descriptor for reading with trans=fd 80 rfdno=n the file descriptor for reading with trans=fd
74 81
@@ -100,6 +107,10 @@ OPTIONS
100 any = v9fs does single attach and performs all 107 any = v9fs does single attach and performs all
101 operations as one user 108 operations as one user
102 109
110 cachetag cache tag to use the specified persistent cache.
111 cache tags for existing cache sessions can be listed at
112 /sys/fs/9p/caches. (applies only to cache=fscache)
113
103RESOURCES 114RESOURCES
104========= 115=========
105 116
@@ -118,7 +129,7 @@ and export.
118A Linux version of the 9p server is now maintained under the npfs project 129A Linux version of the 9p server is now maintained under the npfs project
119on sourceforge (http://sourceforge.net/projects/npfs). The currently 130on sourceforge (http://sourceforge.net/projects/npfs). The currently
120maintained version is the single-threaded version of the server (named spfs) 131maintained version is the single-threaded version of the server (named spfs)
121available from the same CVS repository. 132available from the same SVN repository.
122 133
123There are user and developer mailing lists available through the v9fs project 134There are user and developer mailing lists available through the v9fs project
124on sourceforge (http://sourceforge.net/projects/v9fs). 135on sourceforge (http://sourceforge.net/projects/v9fs).
@@ -126,7 +137,8 @@ on sourceforge (http://sourceforge.net/projects/v9fs).
126A stand-alone version of the module (which should build for any 2.6 kernel) 137A stand-alone version of the module (which should build for any 2.6 kernel)
127is available via (http://github.com/ericvh/9p-sac/tree/master) 138is available via (http://github.com/ericvh/9p-sac/tree/master)
128 139
129News and other information is maintained on SWiK (http://swik.net/v9fs). 140News and other information is maintained on SWiK (http://swik.net/v9fs)
141and the Wiki (http://sf.net/apps/mediawiki/v9fs/index.php).
130 142
131Bug reports may be issued through the kernel.org bugzilla 143Bug reports may be issued through the kernel.org bugzilla
132(http://bugzilla.kernel.org) 144(http://bugzilla.kernel.org)
diff --git a/Documentation/filesystems/caching/fscache.txt b/Documentation/filesystems/caching/fscache.txt
index 9e94b9491d89..a91e2e2095b0 100644
--- a/Documentation/filesystems/caching/fscache.txt
+++ b/Documentation/filesystems/caching/fscache.txt
@@ -235,6 +235,7 @@ proc files.
235 neg=N Number of negative lookups made 235 neg=N Number of negative lookups made
236 pos=N Number of positive lookups made 236 pos=N Number of positive lookups made
237 crt=N Number of objects created by lookup 237 crt=N Number of objects created by lookup
238 tmo=N Number of lookups timed out and requeued
238 Updates n=N Number of update cookie requests seen 239 Updates n=N Number of update cookie requests seen
239 nul=N Number of upd reqs given a NULL parent 240 nul=N Number of upd reqs given a NULL parent
240 run=N Number of upd reqs granted CPU time 241 run=N Number of upd reqs granted CPU time
@@ -250,8 +251,10 @@ proc files.
250 ok=N Number of successful alloc reqs 251 ok=N Number of successful alloc reqs
251 wt=N Number of alloc reqs that waited on lookup completion 252 wt=N Number of alloc reqs that waited on lookup completion
252 nbf=N Number of alloc reqs rejected -ENOBUFS 253 nbf=N Number of alloc reqs rejected -ENOBUFS
254 int=N Number of alloc reqs aborted -ERESTARTSYS
253 ops=N Number of alloc reqs submitted 255 ops=N Number of alloc reqs submitted
254 owt=N Number of alloc reqs waited for CPU time 256 owt=N Number of alloc reqs waited for CPU time
257 abt=N Number of alloc reqs aborted due to object death
255 Retrvls n=N Number of retrieval (read) requests seen 258 Retrvls n=N Number of retrieval (read) requests seen
256 ok=N Number of successful retr reqs 259 ok=N Number of successful retr reqs
257 wt=N Number of retr reqs that waited on lookup completion 260 wt=N Number of retr reqs that waited on lookup completion
@@ -261,6 +264,7 @@ proc files.
261 oom=N Number of retr reqs failed -ENOMEM 264 oom=N Number of retr reqs failed -ENOMEM
262 ops=N Number of retr reqs submitted 265 ops=N Number of retr reqs submitted
263 owt=N Number of retr reqs waited for CPU time 266 owt=N Number of retr reqs waited for CPU time
267 abt=N Number of retr reqs aborted due to object death
264 Stores n=N Number of storage (write) requests seen 268 Stores n=N Number of storage (write) requests seen
265 ok=N Number of successful store reqs 269 ok=N Number of successful store reqs
266 agn=N Number of store reqs on a page already pending storage 270 agn=N Number of store reqs on a page already pending storage
@@ -268,12 +272,37 @@ proc files.
268 oom=N Number of store reqs failed -ENOMEM 272 oom=N Number of store reqs failed -ENOMEM
269 ops=N Number of store reqs submitted 273 ops=N Number of store reqs submitted
270 run=N Number of store reqs granted CPU time 274 run=N Number of store reqs granted CPU time
275 pgs=N Number of pages given store req processing time
276 rxd=N Number of store reqs deleted from tracking tree
277 olm=N Number of store reqs over store limit
278 VmScan nos=N Number of release reqs against pages with no pending store
279 gon=N Number of release reqs against pages stored by time lock granted
280 bsy=N Number of release reqs ignored due to in-progress store
281 can=N Number of page stores cancelled due to release req
271 Ops pend=N Number of times async ops added to pending queues 282 Ops pend=N Number of times async ops added to pending queues
272 run=N Number of times async ops given CPU time 283 run=N Number of times async ops given CPU time
273 enq=N Number of times async ops queued for processing 284 enq=N Number of times async ops queued for processing
285 can=N Number of async ops cancelled
286 rej=N Number of async ops rejected due to object lookup/create failure
274 dfr=N Number of async ops queued for deferred release 287 dfr=N Number of async ops queued for deferred release
275 rel=N Number of async ops released 288 rel=N Number of async ops released
276 gc=N Number of deferred-release async ops garbage collected 289 gc=N Number of deferred-release async ops garbage collected
290 CacheOp alo=N Number of in-progress alloc_object() cache ops
291 luo=N Number of in-progress lookup_object() cache ops
292 luc=N Number of in-progress lookup_complete() cache ops
293 gro=N Number of in-progress grab_object() cache ops
294 upo=N Number of in-progress update_object() cache ops
295 dro=N Number of in-progress drop_object() cache ops
296 pto=N Number of in-progress put_object() cache ops
297 syn=N Number of in-progress sync_cache() cache ops
298 atc=N Number of in-progress attr_changed() cache ops
299 rap=N Number of in-progress read_or_alloc_page() cache ops
300 ras=N Number of in-progress read_or_alloc_pages() cache ops
301 alp=N Number of in-progress allocate_page() cache ops
302 als=N Number of in-progress allocate_pages() cache ops
303 wrp=N Number of in-progress write_page() cache ops
304 ucp=N Number of in-progress uncache_page() cache ops
305 dsp=N Number of in-progress dissociate_pages() cache ops
277 306
278 307
279 (*) /proc/fs/fscache/histogram 308 (*) /proc/fs/fscache/histogram
@@ -299,6 +328,87 @@ proc files.
299 jiffy range covered, and the SECS field the equivalent number of seconds. 328 jiffy range covered, and the SECS field the equivalent number of seconds.
300 329
301 330
331===========
332OBJECT LIST
333===========
334
335If CONFIG_FSCACHE_OBJECT_LIST is enabled, the FS-Cache facility will maintain a
336list of all the objects currently allocated and allow them to be viewed
337through:
338
339 /proc/fs/fscache/objects
340
341This will look something like:
342
343 [root@andromeda ~]# head /proc/fs/fscache/objects
344 OBJECT PARENT STAT CHLDN OPS OOP IPR EX READS EM EV F S | NETFS_COOKIE_DEF TY FL NETFS_DATA OBJECT_KEY, AUX_DATA
345 ======== ======== ==== ===== === === === == ===== == == = = | ================ == == ================ ================
346 17e4b 2 ACTV 0 0 0 0 0 0 7b 4 0 8 | NFS.fh DT 0 ffff88001dd82820 010006017edcf8bbc93b43298fdfbe71e50b57b13a172c0117f38472, e567634700000000000000000000000063f2404a000000000000000000000000c9030000000000000000000063f2404a
347 1693a 2 ACTV 0 0 0 0 0 0 7b 4 0 8 | NFS.fh DT 0 ffff88002db23380 010006017edcf8bbc93b43298fdfbe71e50b57b1e0162c01a2df0ea6, 420ebc4a000000000000000000000000420ebc4a0000000000000000000000000e1801000000000000000000420ebc4a
348
349where the first set of columns before the '|' describe the object:
350
351 COLUMN DESCRIPTION
352 ======= ===============================================================
353 OBJECT Object debugging ID (appears as OBJ%x in some debug messages)
354 PARENT Debugging ID of parent object
355 STAT Object state
356 CHLDN Number of child objects of this object
357 OPS Number of outstanding operations on this object
358 OOP Number of outstanding child object management operations
359 IPR
360 EX Number of outstanding exclusive operations
361 READS Number of outstanding read operations
362 EM Object's event mask
363 EV Events raised on this object
364 F Object flags
365 S Object slow-work work item flags
366
367and the second set of columns describe the object's cookie, if present:
368
369 COLUMN DESCRIPTION
370 =============== =======================================================
371 NETFS_COOKIE_DEF Name of netfs cookie definition
372 TY Cookie type (IX - index, DT - data, hex - special)
373 FL Cookie flags
374 NETFS_DATA Netfs private data stored in the cookie
375 OBJECT_KEY Object key } 1 column, with separating comma
376 AUX_DATA Object aux data } presence may be configured
377
378The data shown may be filtered by attaching the a key to an appropriate keyring
379before viewing the file. Something like:
380
381 keyctl add user fscache:objlist <restrictions> @s
382
383where <restrictions> are a selection of the following letters:
384
385 K Show hexdump of object key (don't show if not given)
386 A Show hexdump of object aux data (don't show if not given)
387
388and the following paired letters:
389
390 C Show objects that have a cookie
391 c Show objects that don't have a cookie
392 B Show objects that are busy
393 b Show objects that aren't busy
394 W Show objects that have pending writes
395 w Show objects that don't have pending writes
396 R Show objects that have outstanding reads
397 r Show objects that don't have outstanding reads
398 S Show objects that have slow work queued
399 s Show objects that don't have slow work queued
400
401If neither side of a letter pair is given, then both are implied. For example:
402
403 keyctl add user fscache:objlist KB @s
404
405shows objects that are busy, and lists their object keys, but does not dump
406their auxiliary data. It also implies "CcWwRrSs", but as 'B' is given, 'b' is
407not implied.
408
409By default all objects and all fields will be shown.
410
411
302========= 412=========
303DEBUGGING 413DEBUGGING
304========= 414=========
diff --git a/Documentation/filesystems/caching/netfs-api.txt b/Documentation/filesystems/caching/netfs-api.txt
index 2666b1ed5e9e..1902c57b72ef 100644
--- a/Documentation/filesystems/caching/netfs-api.txt
+++ b/Documentation/filesystems/caching/netfs-api.txt
@@ -641,7 +641,7 @@ data file must be retired (see the relinquish cookie function below).
641 641
642Furthermore, note that this does not cancel the asynchronous read or write 642Furthermore, note that this does not cancel the asynchronous read or write
643operation started by the read/alloc and write functions, so the page 643operation started by the read/alloc and write functions, so the page
644invalidation and release functions must use: 644invalidation functions must use:
645 645
646 bool fscache_check_page_write(struct fscache_cookie *cookie, 646 bool fscache_check_page_write(struct fscache_cookie *cookie,
647 struct page *page); 647 struct page *page);
@@ -654,6 +654,25 @@ to see if a page is being written to the cache, and:
654to wait for it to finish if it is. 654to wait for it to finish if it is.
655 655
656 656
657When releasepage() is being implemented, a special FS-Cache function exists to
658manage the heuristics of coping with vmscan trying to eject pages, which may
659conflict with the cache trying to write pages to the cache (which may itself
660need to allocate memory):
661
662 bool fscache_maybe_release_page(struct fscache_cookie *cookie,
663 struct page *page,
664 gfp_t gfp);
665
666This takes the netfs cookie, and the page and gfp arguments as supplied to
667releasepage(). It will return false if the page cannot be released yet for
668some reason and if it returns true, the page has been uncached and can now be
669released.
670
671To make a page available for release, this function may wait for an outstanding
672storage request to complete, or it may attempt to cancel the storage request -
673in which case the page will not be stored in the cache this time.
674
675
657========================== 676==========================
658INDEX AND DATA FILE UPDATE 677INDEX AND DATA FILE UPDATE
659========================== 678==========================
diff --git a/Documentation/filesystems/ext3.txt b/Documentation/filesystems/ext3.txt
index 570f9bd9be2b..05d5cf1d743f 100644
--- a/Documentation/filesystems/ext3.txt
+++ b/Documentation/filesystems/ext3.txt
@@ -123,10 +123,18 @@ resuid=n The user ID which may use the reserved blocks.
123 123
124sb=n Use alternate superblock at this location. 124sb=n Use alternate superblock at this location.
125 125
126quota 126quota These options are ignored by the filesystem. They
127noquota 127noquota are used only by quota tools to recognize volumes
128grpquota 128grpquota where quota should be turned on. See documentation
129usrquota 129usrquota in the quota-tools package for more details
130 (http://sourceforge.net/projects/linuxquota).
131
132jqfmt=<quota type> These options tell filesystem details about quota
133usrjquota=<file> so that quota information can be properly updated
134grpjquota=<file> during journal replay. They replace the above
135 quota options. See documentation in the quota-tools
136 package for more details
137 (http://sourceforge.net/projects/linuxquota).
130 138
131bh (*) ext3 associates buffer heads to data pages to 139bh (*) ext3 associates buffer heads to data pages to
132nobh (a) cache disk block mapping information 140nobh (a) cache disk block mapping information
diff --git a/Documentation/filesystems/ext4.txt b/Documentation/filesystems/ext4.txt
index 18b5ec8cea45..6d94e0696f8c 100644
--- a/Documentation/filesystems/ext4.txt
+++ b/Documentation/filesystems/ext4.txt
@@ -134,9 +134,15 @@ ro Mount filesystem read only. Note that ext4 will
134 mount options "ro,noload" can be used to prevent 134 mount options "ro,noload" can be used to prevent
135 writes to the filesystem. 135 writes to the filesystem.
136 136
137journal_checksum Enable checksumming of the journal transactions.
138 This will allow the recovery code in e2fsck and the
139 kernel to detect corruption in the kernel. It is a
140 compatible change and will be ignored by older kernels.
141
137journal_async_commit Commit block can be written to disk without waiting 142journal_async_commit Commit block can be written to disk without waiting
138 for descriptor blocks. If enabled older kernels cannot 143 for descriptor blocks. If enabled older kernels cannot
139 mount the device. 144 mount the device. This will enable 'journal_checksum'
145 internally.
140 146
141journal=update Update the ext4 file system's journal to the current 147journal=update Update the ext4 file system's journal to the current
142 format. 148 format.
@@ -282,9 +288,16 @@ stripe=n Number of filesystem blocks that mballoc will try
282 to use for allocation size and alignment. For RAID5/6 288 to use for allocation size and alignment. For RAID5/6
283 systems this should be the number of data 289 systems this should be the number of data
284 disks * RAID chunk size in file system blocks. 290 disks * RAID chunk size in file system blocks.
285delalloc (*) Deferring block allocation until write-out time. 291
286nodelalloc Disable delayed allocation. Blocks are allocation 292delalloc (*) Defer block allocation until just before ext4
287 when data is copied from user to page cache. 293 writes out the block(s) in question. This
294 allows ext4 to better allocation decisions
295 more efficiently.
296nodelalloc Disable delayed allocation. Blocks are allocated
297 when the data is copied from userspace to the
298 page cache, either via the write(2) system call
299 or when an mmap'ed page which was previously
300 unallocated is written for the first time.
288 301
289max_batch_time=usec Maximum amount of time ext4 should wait for 302max_batch_time=usec Maximum amount of time ext4 should wait for
290 additional filesystem operations to be batch 303 additional filesystem operations to be batch
diff --git a/Documentation/filesystems/ncpfs.txt b/Documentation/filesystems/ncpfs.txt
index f12c30c93f2f..5af164f4b37b 100644
--- a/Documentation/filesystems/ncpfs.txt
+++ b/Documentation/filesystems/ncpfs.txt
@@ -7,6 +7,6 @@ ftp.gwdg.de/pub/linux/misc/ncpfs, but sunsite and its many mirrors
7will have it as well. 7will have it as well.
8 8
9Related products are linware and mars_nwe, which will give Linux partial 9Related products are linware and mars_nwe, which will give Linux partial
10NetWare server functionality. Linware's home site is 10NetWare server functionality.
11klokan.sh.cvut.cz/pub/linux/linware; mars_nwe can be found on 11
12ftp.gwdg.de/pub/linux/misc/ncpfs. 12mars_nwe can be found on ftp.gwdg.de/pub/linux/misc/ncpfs.
diff --git a/Documentation/filesystems/nfs41-server.txt b/Documentation/filesystems/nfs41-server.txt
index 05d81cbcb2e1..5920fe26e6ff 100644
--- a/Documentation/filesystems/nfs41-server.txt
+++ b/Documentation/filesystems/nfs41-server.txt
@@ -11,6 +11,11 @@ the /proc/fs/nfsd/versions control file. Note that to write this
11control file, the nfsd service must be taken down. Use your user-mode 11control file, the nfsd service must be taken down. Use your user-mode
12nfs-utils to set this up; see rpc.nfsd(8) 12nfs-utils to set this up; see rpc.nfsd(8)
13 13
14(Warning: older servers will interpret "+4.1" and "-4.1" as "+4" and
15"-4", respectively. Therefore, code meant to work on both new and old
16kernels must turn 4.1 on or off *before* turning support for version 4
17on or off; rpc.nfsd does this correctly.)
18
14The NFSv4 minorversion 1 (NFSv4.1) implementation in nfsd is based 19The NFSv4 minorversion 1 (NFSv4.1) implementation in nfsd is based
15on the latest NFSv4.1 Internet Draft: 20on the latest NFSv4.1 Internet Draft:
16http://tools.ietf.org/html/draft-ietf-nfsv4-minorversion1-29 21http://tools.ietf.org/html/draft-ietf-nfsv4-minorversion1-29
@@ -25,6 +30,49 @@ are still under development out of tree.
25See http://wiki.linux-nfs.org/wiki/index.php/PNFS_prototype_design 30See http://wiki.linux-nfs.org/wiki/index.php/PNFS_prototype_design
26for more information. 31for more information.
27 32
33The current implementation is intended for developers only: while it
34does support ordinary file operations on clients we have tested against
35(including the linux client), it is incomplete in ways which may limit
36features unexpectedly, cause known bugs in rare cases, or cause
37interoperability problems with future clients. Known issues:
38
39 - gss support is questionable: currently mounts with kerberos
40 from a linux client are possible, but we aren't really
41 conformant with the spec (for example, we don't use kerberos
42 on the backchannel correctly).
43 - no trunking support: no clients currently take advantage of
44 trunking, but this is a mandatory failure, and its use is
45 recommended to clients in a number of places. (E.g. to ensure
46 timely renewal in case an existing connection's retry timeouts
47 have gotten too long; see section 8.3 of the draft.)
48 Therefore, lack of this feature may cause future clients to
49 fail.
50 - Incomplete backchannel support: incomplete backchannel gss
51 support and no support for BACKCHANNEL_CTL mean that
52 callbacks (hence delegations and layouts) may not be
53 available and clients confused by the incomplete
54 implementation may fail.
55 - Server reboot recovery is unsupported; if the server reboots,
56 clients may fail.
57 - We do not support SSV, which provides security for shared
58 client-server state (thus preventing unauthorized tampering
59 with locks and opens, for example). It is mandatory for
60 servers to support this, though no clients use it yet.
61 - Mandatory operations which we do not support, such as
62 DESTROY_CLIENTID, FREE_STATEID, SECINFO_NO_NAME, and
63 TEST_STATEID, are not currently used by clients, but will be
64 (and the spec recommends their uses in common cases), and
65 clients should not be expected to know how to recover from the
66 case where they are not supported. This will eventually cause
67 interoperability failures.
68
69In addition, some limitations are inherited from the current NFSv4
70implementation:
71
72 - Incomplete delegation enforcement: if a file is renamed or
73 unlinked, a client holding a delegation may continue to
74 indefinitely allow opens of the file under the old name.
75
28The table below, taken from the NFSv4.1 document, lists 76The table below, taken from the NFSv4.1 document, lists
29the operations that are mandatory to implement (REQ), optional 77the operations that are mandatory to implement (REQ), optional
30(OPT), and NFSv4.0 operations that are required not to implement (MNI) 78(OPT), and NFSv4.0 operations that are required not to implement (MNI)
@@ -142,6 +190,12 @@ NS*| CB_WANTS_CANCELLED | OPT | FDELG, | Section 20.10 |
142 190
143Implementation notes: 191Implementation notes:
144 192
193DELEGPURGE:
194* mandatory only for servers that support CLAIM_DELEGATE_PREV and/or
195 CLAIM_DELEG_PREV_FH (which allows clients to keep delegations that
196 persist across client reboots). Thus we need not implement this for
197 now.
198
145EXCHANGE_ID: 199EXCHANGE_ID:
146* only SP4_NONE state protection supported 200* only SP4_NONE state protection supported
147* implementation ids are ignored 201* implementation ids are ignored
diff --git a/Documentation/filesystems/nfsroot.txt b/Documentation/filesystems/nfsroot.txt
index 68baddf3c3e0..3ba0b945aaf8 100644
--- a/Documentation/filesystems/nfsroot.txt
+++ b/Documentation/filesystems/nfsroot.txt
@@ -105,7 +105,7 @@ ip=<client-ip>:<server-ip>:<gw-ip>:<netmask>:<hostname>:<device>:<autoconf>
105 the client address and this parameter is NOT empty only 105 the client address and this parameter is NOT empty only
106 replies from the specified server are accepted. 106 replies from the specified server are accepted.
107 107
108 Only required for for NFS root. That is autoconfiguration 108 Only required for NFS root. That is autoconfiguration
109 will not be triggered if it is missing and NFS root is not 109 will not be triggered if it is missing and NFS root is not
110 in operation. 110 in operation.
111 111
diff --git a/Documentation/filesystems/ocfs2.txt b/Documentation/filesystems/ocfs2.txt
index c2a0871280a0..c58b9f5ba002 100644
--- a/Documentation/filesystems/ocfs2.txt
+++ b/Documentation/filesystems/ocfs2.txt
@@ -20,15 +20,16 @@ Lots of code taken from ext3 and other projects.
20Authors in alphabetical order: 20Authors in alphabetical order:
21Joel Becker <joel.becker@oracle.com> 21Joel Becker <joel.becker@oracle.com>
22Zach Brown <zach.brown@oracle.com> 22Zach Brown <zach.brown@oracle.com>
23Mark Fasheh <mark.fasheh@oracle.com> 23Mark Fasheh <mfasheh@suse.com>
24Kurt Hackel <kurt.hackel@oracle.com> 24Kurt Hackel <kurt.hackel@oracle.com>
25Tao Ma <tao.ma@oracle.com>
25Sunil Mushran <sunil.mushran@oracle.com> 26Sunil Mushran <sunil.mushran@oracle.com>
26Manish Singh <manish.singh@oracle.com> 27Manish Singh <manish.singh@oracle.com>
28Tiger Yang <tiger.yang@oracle.com>
27 29
28Caveats 30Caveats
29======= 31=======
30Features which OCFS2 does not support yet: 32Features which OCFS2 does not support yet:
31 - quotas
32 - Directory change notification (F_NOTIFY) 33 - Directory change notification (F_NOTIFY)
33 - Distributed Caching (F_SETLEASE/F_GETLEASE/break_lease) 34 - Distributed Caching (F_SETLEASE/F_GETLEASE/break_lease)
34 35
@@ -70,7 +71,6 @@ commit=nrsec (*) Ocfs2 can be told to sync all its data and metadata
70 performance. 71 performance.
71localalloc=8(*) Allows custom localalloc size in MB. If the value is too 72localalloc=8(*) Allows custom localalloc size in MB. If the value is too
72 large, the fs will silently revert it to the default. 73 large, the fs will silently revert it to the default.
73 Localalloc is not enabled for local mounts.
74localflocks This disables cluster aware flock. 74localflocks This disables cluster aware flock.
75inode64 Indicates that Ocfs2 is allowed to create inodes at 75inode64 Indicates that Ocfs2 is allowed to create inodes at
76 any location in the filesystem, including those which 76 any location in the filesystem, including those which
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index ffead13f9443..2c48f945546b 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -176,6 +176,7 @@ read the file /proc/PID/status:
176 CapBnd: ffffffffffffffff 176 CapBnd: ffffffffffffffff
177 voluntary_ctxt_switches: 0 177 voluntary_ctxt_switches: 0
178 nonvoluntary_ctxt_switches: 1 178 nonvoluntary_ctxt_switches: 1
179 Stack usage: 12 kB
179 180
180This shows you nearly the same information you would get if you viewed it with 181This shows you nearly the same information you would get if you viewed it with
181the ps command. In fact, ps uses the proc file system to obtain its 182the ps command. In fact, ps uses the proc file system to obtain its
@@ -229,6 +230,7 @@ Table 1-2: Contents of the statm files (as of 2.6.30-rc7)
229 Mems_allowed_list Same as previous, but in "list format" 230 Mems_allowed_list Same as previous, but in "list format"
230 voluntary_ctxt_switches number of voluntary context switches 231 voluntary_ctxt_switches number of voluntary context switches
231 nonvoluntary_ctxt_switches number of non voluntary context switches 232 nonvoluntary_ctxt_switches number of non voluntary context switches
233 Stack usage: stack usage high water mark (round up to page size)
232.............................................................................. 234..............................................................................
233 235
234Table 1-3: Contents of the statm files (as of 2.6.8-rc3) 236Table 1-3: Contents of the statm files (as of 2.6.8-rc3)
@@ -307,7 +309,7 @@ address perms offset dev inode pathname
30708049000-0804a000 rw-p 00001000 03:00 8312 /opt/test 30908049000-0804a000 rw-p 00001000 03:00 8312 /opt/test
3080804a000-0806b000 rw-p 00000000 00:00 0 [heap] 3100804a000-0806b000 rw-p 00000000 00:00 0 [heap]
309a7cb1000-a7cb2000 ---p 00000000 00:00 0 311a7cb1000-a7cb2000 ---p 00000000 00:00 0
310a7cb2000-a7eb2000 rw-p 00000000 00:00 0 312a7cb2000-a7eb2000 rw-p 00000000 00:00 0 [threadstack:001ff4b4]
311a7eb2000-a7eb3000 ---p 00000000 00:00 0 313a7eb2000-a7eb3000 ---p 00000000 00:00 0
312a7eb3000-a7ed5000 rw-p 00000000 00:00 0 314a7eb3000-a7ed5000 rw-p 00000000 00:00 0
313a7ed5000-a8008000 r-xp 00000000 03:00 4222 /lib/libc.so.6 315a7ed5000-a8008000 r-xp 00000000 03:00 4222 /lib/libc.so.6
@@ -343,6 +345,7 @@ is not associated with a file:
343 [stack] = the stack of the main process 345 [stack] = the stack of the main process
344 [vdso] = the "virtual dynamic shared object", 346 [vdso] = the "virtual dynamic shared object",
345 the kernel system call handler 347 the kernel system call handler
348 [threadstack:xxxxxxxx] = the stack of the thread, xxxxxxxx is the stack size
346 349
347 or if empty, the mapping is anonymous. 350 or if empty, the mapping is anonymous.
348 351
@@ -375,6 +378,19 @@ of memory currently marked as referenced or accessed.
375This file is only present if the CONFIG_MMU kernel configuration option is 378This file is only present if the CONFIG_MMU kernel configuration option is
376enabled. 379enabled.
377 380
381The /proc/PID/clear_refs is used to reset the PG_Referenced and ACCESSED/YOUNG
382bits on both physical and virtual pages associated with a process.
383To clear the bits for all the pages associated with the process
384 > echo 1 > /proc/PID/clear_refs
385
386To clear the bits for the anonymous pages associated with the process
387 > echo 2 > /proc/PID/clear_refs
388
389To clear the bits for the file mapped pages associated with the process
390 > echo 3 > /proc/PID/clear_refs
391Any other value written to /proc/PID/clear_refs will have no effect.
392
393
3781.2 Kernel data 3941.2 Kernel data
379--------------- 395---------------
380 396
@@ -1032,9 +1048,9 @@ Various pieces of information about kernel activity are available in the
1032since the system first booted. For a quick look, simply cat the file: 1048since the system first booted. For a quick look, simply cat the file:
1033 1049
1034 > cat /proc/stat 1050 > cat /proc/stat
1035 cpu 2255 34 2290 22625563 6290 127 456 0 1051 cpu 2255 34 2290 22625563 6290 127 456 0 0
1036 cpu0 1132 34 1441 11311718 3675 127 438 0 1052 cpu0 1132 34 1441 11311718 3675 127 438 0 0
1037 cpu1 1123 0 849 11313845 2614 0 18 0 1053 cpu1 1123 0 849 11313845 2614 0 18 0 0
1038 intr 114930548 113199788 3 0 5 263 0 4 [... lots more numbers ...] 1054 intr 114930548 113199788 3 0 5 263 0 4 [... lots more numbers ...]
1039 ctxt 1990473 1055 ctxt 1990473
1040 btime 1062191376 1056 btime 1062191376
@@ -1056,6 +1072,7 @@ second). The meanings of the columns are as follows, from left to right:
1056- irq: servicing interrupts 1072- irq: servicing interrupts
1057- softirq: servicing softirqs 1073- softirq: servicing softirqs
1058- steal: involuntary wait 1074- steal: involuntary wait
1075- guest: running a guest
1059 1076
1060The "intr" line gives counts of interrupts serviced since boot time, for each 1077The "intr" line gives counts of interrupts serviced since boot time, for each
1061of the possible system interrupts. The first column is the total of all 1078of the possible system interrupts. The first column is the total of all
@@ -1096,7 +1113,6 @@ Table 1-12: Files in /proc/fs/ext4/<devname>
1096.............................................................................. 1113..............................................................................
1097 File Content 1114 File Content
1098 mb_groups details of multiblock allocator buddy cache of free blocks 1115 mb_groups details of multiblock allocator buddy cache of free blocks
1099 mb_history multiblock allocation history
1100.............................................................................. 1116..............................................................................
1101 1117
1102 1118
@@ -1191,7 +1207,7 @@ The following heuristics are then applied:
1191 * if the task was reniced, its score doubles 1207 * if the task was reniced, its score doubles
1192 * superuser or direct hardware access tasks (CAP_SYS_ADMIN, CAP_SYS_RESOURCE 1208 * superuser or direct hardware access tasks (CAP_SYS_ADMIN, CAP_SYS_RESOURCE
1193 or CAP_SYS_RAWIO) have their score divided by 4 1209 or CAP_SYS_RAWIO) have their score divided by 4
1194 * if oom condition happened in one cpuset and checked task does not belong 1210 * if oom condition happened in one cpuset and checked process does not belong
1195 to it, its score is divided by 8 1211 to it, its score is divided by 8
1196 * the resulting score is multiplied by two to the power of oom_adj, i.e. 1212 * the resulting score is multiplied by two to the power of oom_adj, i.e.
1197 points <<= oom_adj when it is positive and 1213 points <<= oom_adj when it is positive and
diff --git a/Documentation/filesystems/sharedsubtree.txt b/Documentation/filesystems/sharedsubtree.txt
index 736540045dc7..23a181074f94 100644
--- a/Documentation/filesystems/sharedsubtree.txt
+++ b/Documentation/filesystems/sharedsubtree.txt
@@ -4,7 +4,7 @@ Shared Subtrees
4Contents: 4Contents:
5 1) Overview 5 1) Overview
6 2) Features 6 2) Features
7 3) smount command 7 3) Setting mount states
8 4) Use-case 8 4) Use-case
9 5) Detailed semantics 9 5) Detailed semantics
10 6) Quiz 10 6) Quiz
@@ -41,14 +41,14 @@ replicas continue to be exactly same.
41 41
42 Here is an example: 42 Here is an example:
43 43
44 Lets say /mnt has a mount that is shared. 44 Let's say /mnt has a mount that is shared.
45 mount --make-shared /mnt 45 mount --make-shared /mnt
46 46
47 note: mount command does not yet support the --make-shared flag. 47 Note: mount(8) command now supports the --make-shared flag,
48 I have included a small C program which does the same by executing 48 so the sample 'smount' program is no longer needed and has been
49 'smount /mnt shared' 49 removed.
50 50
51 #mount --bind /mnt /tmp 51 # mount --bind /mnt /tmp
52 The above command replicates the mount at /mnt to the mountpoint /tmp 52 The above command replicates the mount at /mnt to the mountpoint /tmp
53 and the contents of both the mounts remain identical. 53 and the contents of both the mounts remain identical.
54 54
@@ -58,8 +58,8 @@ replicas continue to be exactly same.
58 #ls /tmp 58 #ls /tmp
59 a b c 59 a b c
60 60
61 Now lets say we mount a device at /tmp/a 61 Now let's say we mount a device at /tmp/a
62 #mount /dev/sd0 /tmp/a 62 # mount /dev/sd0 /tmp/a
63 63
64 #ls /tmp/a 64 #ls /tmp/a
65 t1 t2 t2 65 t1 t2 t2
@@ -80,21 +80,20 @@ replicas continue to be exactly same.
80 80
81 Here is an example: 81 Here is an example:
82 82
83 Lets say /mnt has a mount which is shared. 83 Let's say /mnt has a mount which is shared.
84 #mount --make-shared /mnt 84 # mount --make-shared /mnt
85 85
86 Lets bind mount /mnt to /tmp 86 Let's bind mount /mnt to /tmp
87 #mount --bind /mnt /tmp 87 # mount --bind /mnt /tmp
88 88
89 the new mount at /tmp becomes a shared mount and it is a replica of 89 the new mount at /tmp becomes a shared mount and it is a replica of
90 the mount at /mnt. 90 the mount at /mnt.
91 91
92 Now lets make the mount at /tmp; a slave of /mnt 92 Now let's make the mount at /tmp; a slave of /mnt
93 #mount --make-slave /tmp 93 # mount --make-slave /tmp
94 [or smount /tmp slave]
95 94
96 lets mount /dev/sd0 on /mnt/a 95 let's mount /dev/sd0 on /mnt/a
97 #mount /dev/sd0 /mnt/a 96 # mount /dev/sd0 /mnt/a
98 97
99 #ls /mnt/a 98 #ls /mnt/a
100 t1 t2 t3 99 t1 t2 t3
@@ -104,9 +103,9 @@ replicas continue to be exactly same.
104 103
105 Note the mount event has propagated to the mount at /tmp 104 Note the mount event has propagated to the mount at /tmp
106 105
107 However lets see what happens if we mount something on the mount at /tmp 106 However let's see what happens if we mount something on the mount at /tmp
108 107
109 #mount /dev/sd1 /tmp/b 108 # mount /dev/sd1 /tmp/b
110 109
111 #ls /tmp/b 110 #ls /tmp/b
112 s1 s2 s3 111 s1 s2 s3
@@ -124,12 +123,11 @@ replicas continue to be exactly same.
124 123
1252d) A unbindable mount is a unbindable private mount 1242d) A unbindable mount is a unbindable private mount
126 125
127 lets say we have a mount at /mnt and we make is unbindable 126 let's say we have a mount at /mnt and we make is unbindable
128 127
129 #mount --make-unbindable /mnt 128 # mount --make-unbindable /mnt
130 [ smount /mnt unbindable ]
131 129
132 Lets try to bind mount this mount somewhere else. 130 Let's try to bind mount this mount somewhere else.
133 # mount --bind /mnt /tmp 131 # mount --bind /mnt /tmp
134 mount: wrong fs type, bad option, bad superblock on /mnt, 132 mount: wrong fs type, bad option, bad superblock on /mnt,
135 or too many mounted file systems 133 or too many mounted file systems
@@ -137,149 +135,15 @@ replicas continue to be exactly same.
137 Binding a unbindable mount is a invalid operation. 135 Binding a unbindable mount is a invalid operation.
138 136
139 137
1403) smount command 1383) Setting mount states
141 139
142 Currently the mount command is not aware of shared subtree features. 140 The mount command (util-linux package) can be used to set mount
143 Work is in progress to add the support in mount ( util-linux package ). 141 states:
144 Till then use the following program.
145 142
146 ------------------------------------------------------------------------ 143 mount --make-shared mountpoint
147 // 144 mount --make-slave mountpoint
148 //this code was developed my Miklos Szeredi <miklos@szeredi.hu> 145 mount --make-private mountpoint
149 //and modified by Ram Pai <linuxram@us.ibm.com> 146 mount --make-unbindable mountpoint
150 // sample usage:
151 // smount /tmp shared
152 //
153 #include <stdio.h>
154 #include <stdlib.h>
155 #include <unistd.h>
156 #include <string.h>
157 #include <sys/mount.h>
158 #include <sys/fsuid.h>
159
160 #ifndef MS_REC
161 #define MS_REC 0x4000 /* 16384: Recursive loopback */
162 #endif
163
164 #ifndef MS_SHARED
165 #define MS_SHARED 1<<20 /* Shared */
166 #endif
167
168 #ifndef MS_PRIVATE
169 #define MS_PRIVATE 1<<18 /* Private */
170 #endif
171
172 #ifndef MS_SLAVE
173 #define MS_SLAVE 1<<19 /* Slave */
174 #endif
175
176 #ifndef MS_UNBINDABLE
177 #define MS_UNBINDABLE 1<<17 /* Unbindable */
178 #endif
179
180 int main(int argc, char *argv[])
181 {
182 int type;
183 if(argc != 3) {
184 fprintf(stderr, "usage: %s dir "
185 "<rshared|rslave|rprivate|runbindable|shared|slave"
186 "|private|unbindable>\n" , argv[0]);
187 return 1;
188 }
189
190 fprintf(stdout, "%s %s %s\n", argv[0], argv[1], argv[2]);
191
192 if (strcmp(argv[2],"rshared")==0)
193 type=(MS_SHARED|MS_REC);
194 else if (strcmp(argv[2],"rslave")==0)
195 type=(MS_SLAVE|MS_REC);
196 else if (strcmp(argv[2],"rprivate")==0)
197 type=(MS_PRIVATE|MS_REC);
198 else if (strcmp(argv[2],"runbindable")==0)
199 type=(MS_UNBINDABLE|MS_REC);
200 else if (strcmp(argv[2],"shared")==0)
201 type=MS_SHARED;
202 else if (strcmp(argv[2],"slave")==0)
203 type=MS_SLAVE;
204 else if (strcmp(argv[2],"private")==0)
205 type=MS_PRIVATE;
206 else if (strcmp(argv[2],"unbindable")==0)
207 type=MS_UNBINDABLE;
208 else {
209 fprintf(stderr, "invalid operation: %s\n", argv[2]);
210 return 1;
211 }
212 setfsuid(getuid());
213
214 if(mount("", argv[1], "dontcare", type, "") == -1) {
215 perror("mount");
216 return 1;
217 }
218 return 0;
219 }
220 -----------------------------------------------------------------------
221
222 Copy the above code snippet into smount.c
223 gcc -o smount smount.c
224
225
226 (i) To mark all the mounts under /mnt as shared execute the following
227 command:
228
229 smount /mnt rshared
230 the corresponding syntax planned for mount command is
231 mount --make-rshared /mnt
232
233 just to mark a mount /mnt as shared, execute the following
234 command:
235 smount /mnt shared
236 the corresponding syntax planned for mount command is
237 mount --make-shared /mnt
238
239 (ii) To mark all the shared mounts under /mnt as slave execute the
240 following
241
242 command:
243 smount /mnt rslave
244 the corresponding syntax planned for mount command is
245 mount --make-rslave /mnt
246
247 just to mark a mount /mnt as slave, execute the following
248 command:
249 smount /mnt slave
250 the corresponding syntax planned for mount command is
251 mount --make-slave /mnt
252
253 (iii) To mark all the mounts under /mnt as private execute the
254 following command:
255
256 smount /mnt rprivate
257 the corresponding syntax planned for mount command is
258 mount --make-rprivate /mnt
259
260 just to mark a mount /mnt as private, execute the following
261 command:
262 smount /mnt private
263 the corresponding syntax planned for mount command is
264 mount --make-private /mnt
265
266 NOTE: by default all the mounts are created as private. But if
267 you want to change some shared/slave/unbindable mount as
268 private at a later point in time, this command can help.
269
270 (iv) To mark all the mounts under /mnt as unbindable execute the
271 following
272
273 command:
274 smount /mnt runbindable
275 the corresponding syntax planned for mount command is
276 mount --make-runbindable /mnt
277
278 just to mark a mount /mnt as unbindable, execute the following
279 command:
280 smount /mnt unbindable
281 the corresponding syntax planned for mount command is
282 mount --make-unbindable /mnt
283 147
284 148
2854) Use cases 1494) Use cases
@@ -350,7 +214,7 @@ replicas continue to be exactly same.
350 mount --rbind / /view/v3 214 mount --rbind / /view/v3
351 mount --rbind / /view/v4 215 mount --rbind / /view/v4
352 216
353 and if /usr has a versioning filesystem mounted, than that 217 and if /usr has a versioning filesystem mounted, then that
354 mount appears at /view/v1/usr, /view/v2/usr, /view/v3/usr and 218 mount appears at /view/v1/usr, /view/v2/usr, /view/v3/usr and
355 /view/v4/usr too 219 /view/v4/usr too
356 220
@@ -390,7 +254,7 @@ replicas continue to be exactly same.
390 254
391 For example: 255 For example:
392 mount --make-shared /mnt 256 mount --make-shared /mnt
393 mount --bin /mnt /tmp 257 mount --bind /mnt /tmp
394 258
395 The mount at /mnt and that at /tmp are both shared and belong 259 The mount at /mnt and that at /tmp are both shared and belong
396 to the same peer group. Anything mounted or unmounted under 260 to the same peer group. Anything mounted or unmounted under
@@ -558,7 +422,7 @@ replicas continue to be exactly same.
558 then the subtree under the unbindable mount is pruned in the new 422 then the subtree under the unbindable mount is pruned in the new
559 location. 423 location.
560 424
561 eg: lets say we have the following mount tree. 425 eg: let's say we have the following mount tree.
562 426
563 A 427 A
564 / \ 428 / \
@@ -566,7 +430,7 @@ replicas continue to be exactly same.
566 / \ / \ 430 / \ / \
567 D E F G 431 D E F G
568 432
569 Lets say all the mount except the mount C in the tree are 433 Let's say all the mount except the mount C in the tree are
570 of a type other than unbindable. 434 of a type other than unbindable.
571 435
572 If this tree is rbound to say Z 436 If this tree is rbound to say Z
@@ -683,13 +547,13 @@ replicas continue to be exactly same.
683 'b' on mounts that receive propagation from mount 'B' and does not have 547 'b' on mounts that receive propagation from mount 'B' and does not have
684 sub-mounts within them are unmounted. 548 sub-mounts within them are unmounted.
685 549
686 Example: Lets say 'B1', 'B2', 'B3' are shared mounts that propagate to 550 Example: Let's say 'B1', 'B2', 'B3' are shared mounts that propagate to
687 each other. 551 each other.
688 552
689 lets say 'A1', 'A2', 'A3' are first mounted at dentry 'b' on mount 553 let's say 'A1', 'A2', 'A3' are first mounted at dentry 'b' on mount
690 'B1', 'B2' and 'B3' respectively. 554 'B1', 'B2' and 'B3' respectively.
691 555
692 lets say 'C1', 'C2', 'C3' are next mounted at the same dentry 'b' on 556 let's say 'C1', 'C2', 'C3' are next mounted at the same dentry 'b' on
693 mount 'B1', 'B2' and 'B3' respectively. 557 mount 'B1', 'B2' and 'B3' respectively.
694 558
695 if 'C1' is unmounted, all the mounts that are most-recently-mounted on 559 if 'C1' is unmounted, all the mounts that are most-recently-mounted on
@@ -710,7 +574,7 @@ replicas continue to be exactly same.
710 A cloned namespace contains all the mounts as that of the parent 574 A cloned namespace contains all the mounts as that of the parent
711 namespace. 575 namespace.
712 576
713 Lets say 'A' and 'B' are the corresponding mounts in the parent and the 577 Let's say 'A' and 'B' are the corresponding mounts in the parent and the
714 child namespace. 578 child namespace.
715 579
716 If 'A' is shared, then 'B' is also shared and 'A' and 'B' propagate to 580 If 'A' is shared, then 'B' is also shared and 'A' and 'B' propagate to
@@ -759,11 +623,11 @@ replicas continue to be exactly same.
759 mount --make-slave /mnt 623 mount --make-slave /mnt
760 624
761 At this point we have the first mount at /tmp and 625 At this point we have the first mount at /tmp and
762 its root dentry is 1. Lets call this mount 'A' 626 its root dentry is 1. Let's call this mount 'A'
763 And then we have a second mount at /tmp1 with root 627 And then we have a second mount at /tmp1 with root
764 dentry 2. Lets call this mount 'B' 628 dentry 2. Let's call this mount 'B'
765 Next we have a third mount at /mnt with root dentry 629 Next we have a third mount at /mnt with root dentry
766 mnt. Lets call this mount 'C' 630 mnt. Let's call this mount 'C'
767 631
768 'B' is the slave of 'A' and 'C' is a slave of 'B' 632 'B' is the slave of 'A' and 'C' is a slave of 'B'
769 A -> B -> C 633 A -> B -> C
@@ -794,7 +658,7 @@ replicas continue to be exactly same.
794 658
795 Q3 Why is unbindable mount needed? 659 Q3 Why is unbindable mount needed?
796 660
797 Lets say we want to replicate the mount tree at multiple 661 Let's say we want to replicate the mount tree at multiple
798 locations within the same subtree. 662 locations within the same subtree.
799 663
800 if one rbind mounts a tree within the same subtree 'n' times 664 if one rbind mounts a tree within the same subtree 'n' times
@@ -803,7 +667,7 @@ replicas continue to be exactly same.
803 mounts. Here is a example. 667 mounts. Here is a example.
804 668
805 step 1: 669 step 1:
806 lets say the root tree has just two directories with 670 let's say the root tree has just two directories with
807 one vfsmount. 671 one vfsmount.
808 root 672 root
809 / \ 673 / \
@@ -875,7 +739,7 @@ replicas continue to be exactly same.
875 Unclonable mounts come in handy here. 739 Unclonable mounts come in handy here.
876 740
877 step 1: 741 step 1:
878 lets say the root tree has just two directories with 742 let's say the root tree has just two directories with
879 one vfsmount. 743 one vfsmount.
880 root 744 root
881 / \ 745 / \
diff --git a/Documentation/filesystems/vfat.txt b/Documentation/filesystems/vfat.txt
index b58b84b50fa2..eed520fd0c8e 100644
--- a/Documentation/filesystems/vfat.txt
+++ b/Documentation/filesystems/vfat.txt
@@ -102,7 +102,7 @@ shortname=lower|win95|winnt|mixed
102 winnt: emulate the Windows NT rule for display/create. 102 winnt: emulate the Windows NT rule for display/create.
103 mixed: emulate the Windows NT rule for display, 103 mixed: emulate the Windows NT rule for display,
104 emulate the Windows 95 rule for create. 104 emulate the Windows 95 rule for create.
105 Default setting is `lower'. 105 Default setting is `mixed'.
106 106
107tz=UTC -- Interpret timestamps as UTC rather than local time. 107tz=UTC -- Interpret timestamps as UTC rather than local time.
108 This option disables the conversion of timestamps 108 This option disables the conversion of timestamps
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index f49eecf2e573..623f094c9d8d 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt
@@ -536,6 +536,7 @@ struct address_space_operations {
536 /* migrate the contents of a page to the specified target */ 536 /* migrate the contents of a page to the specified target */
537 int (*migratepage) (struct page *, struct page *); 537 int (*migratepage) (struct page *, struct page *);
538 int (*launder_page) (struct page *); 538 int (*launder_page) (struct page *);
539 int (*error_remove_page) (struct mapping *mapping, struct page *page);
539}; 540};
540 541
541 writepage: called by the VM to write a dirty page to backing store. 542 writepage: called by the VM to write a dirty page to backing store.
@@ -694,6 +695,12 @@ struct address_space_operations {
694 prevent redirtying the page, it is kept locked during the whole 695 prevent redirtying the page, it is kept locked during the whole
695 operation. 696 operation.
696 697
698 error_remove_page: normally set to generic_error_remove_page if truncation
699 is ok for this address space. Used for memory failure handling.
700 Setting this implies you deal with pages going away under you,
701 unless you have them locked or reference counts increased.
702
703
697The File Object 704The File Object
698=============== 705===============
699 706