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Author SHA1 Message Date
David Howells 36c9559022 FS-Cache: Object management state machine
Implement the cache object management state machine.

The following documentation is added to illuminate the working of this state
machine.  It will also be added as:

	Documentation/filesystems/caching/object.txt

	     ====================================================
	     IN-KERNEL CACHE OBJECT REPRESENTATION AND MANAGEMENT
	     ====================================================

==============
REPRESENTATION
==============

FS-Cache maintains an in-kernel representation of each object that a netfs is
currently interested in.  Such objects are represented by the fscache_cookie
struct and are referred to as cookies.

FS-Cache also maintains a separate in-kernel representation of the objects that
a cache backend is currently actively caching.  Such objects are represented by
the fscache_object struct.  The cache backends allocate these upon request, and
are expected to embed them in their own representations.  These are referred to
as objects.

There is a 1:N relationship between cookies and objects.  A cookie may be
represented by multiple objects - an index may exist in more than one cache -
or even by no objects (it may not be cached).

Furthermore, both cookies and objects are hierarchical.  The two hierarchies
correspond, but the cookies tree is a superset of the union of the object trees
of multiple caches:

	    NETFS INDEX TREE               :      CACHE 1     :      CACHE 2
	                                   :                  :
	                                   :   +-----------+  :
	                          +----------->|  IObject  |  :
	      +-----------+       |        :   +-----------+  :
	      |  ICookie  |-------+        :         |        :
	      +-----------+       |        :         |        :   +-----------+
	            |             +------------------------------>|  IObject  |
	            |                      :         |        :   +-----------+
	            |                      :         V        :         |
	            |                      :   +-----------+  :         |
	            V             +----------->|  IObject  |  :         |
	      +-----------+       |        :   +-----------+  :         |
	      |  ICookie  |-------+        :         |        :         V
	      +-----------+       |        :         |        :   +-----------+
	            |             +------------------------------>|  IObject  |
	      +-----+-----+                :         |        :   +-----------+
	      |           |                :         |        :         |
	      V           |                :         V        :         |
	+-----------+     |                :   +-----------+  :         |
	|  ICookie  |------------------------->|  IObject  |  :         |
	+-----------+     |                :   +-----------+  :         |
	      |           V                :         |        :         V
	      |     +-----------+          :         |        :   +-----------+
	      |     |  ICookie  |-------------------------------->|  IObject  |
	      |     +-----------+          :         |        :   +-----------+
	      V           |                :         V        :         |
	+-----------+     |                :   +-----------+  :         |
	|  DCookie  |------------------------->|  DObject  |  :         |
	+-----------+     |                :   +-----------+  :         |
	                  |                :                  :         |
	          +-------+-------+        :                  :         |
	          |               |        :                  :         |
	          V               V        :                  :         V
	    +-----------+   +-----------+  :                  :   +-----------+
	    |  DCookie  |   |  DCookie  |------------------------>|  DObject  |
	    +-----------+   +-----------+  :                  :   +-----------+
	                                   :                  :

In the above illustration, ICookie and IObject represent indices and DCookie
and DObject represent data storage objects.  Indices may have representation in
multiple caches, but currently, non-index objects may not.  Objects of any type
may also be entirely unrepresented.

As far as the netfs API goes, the netfs is only actually permitted to see
pointers to the cookies.  The cookies themselves and any objects attached to
those cookies are hidden from it.

===============================
OBJECT MANAGEMENT STATE MACHINE
===============================

Within FS-Cache, each active object is managed by its own individual state
machine.  The state for an object is kept in the fscache_object struct, in
object->state.  A cookie may point to a set of objects that are in different
states.

Each state has an action associated with it that is invoked when the machine
wakes up in that state.  There are four logical sets of states:

 (1) Preparation: states that wait for the parent objects to become ready.  The
     representations are hierarchical, and it is expected that an object must
     be created or accessed with respect to its parent object.

 (2) Initialisation: states that perform lookups in the cache and validate
     what's found and that create on disk any missing metadata.

 (3) Normal running: states that allow netfs operations on objects to proceed
     and that update the state of objects.

 (4) Termination: states that detach objects from their netfs cookies, that
     delete objects from disk, that handle disk and system errors and that free
     up in-memory resources.

In most cases, transitioning between states is in response to signalled events.
When a state has finished processing, it will usually set the mask of events in
which it is interested (object->event_mask) and relinquish the worker thread.
Then when an event is raised (by calling fscache_raise_event()), if the event
is not masked, the object will be queued for processing (by calling
fscache_enqueue_object()).

PROVISION OF CPU TIME
---------------------

The work to be done by the various states is given CPU time by the threads of
the slow work facility (see Documentation/slow-work.txt).  This is used in
preference to the workqueue facility because:

 (1) Threads may be completely occupied for very long periods of time by a
     particular work item.  These state actions may be doing sequences of
     synchronous, journalled disk accesses (lookup, mkdir, create, setxattr,
     getxattr, truncate, unlink, rmdir, rename).

 (2) Threads may do little actual work, but may rather spend a lot of time
     sleeping on I/O.  This means that single-threaded and 1-per-CPU-threaded
     workqueues don't necessarily have the right numbers of threads.

LOCKING SIMPLIFICATION
----------------------

Because only one worker thread may be operating on any particular object's
state machine at once, this simplifies the locking, particularly with respect
to disconnecting the netfs's representation of a cache object (fscache_cookie)
from the cache backend's representation (fscache_object) - which may be
requested from either end.

=================
THE SET OF STATES
=================

The object state machine has a set of states that it can be in.  There are
preparation states in which the object sets itself up and waits for its parent
object to transit to a state that allows access to its children:

 (1) State FSCACHE_OBJECT_INIT.

     Initialise the object and wait for the parent object to become active.  In
     the cache, it is expected that it will not be possible to look an object
     up from the parent object, until that parent object itself has been looked
     up.

There are initialisation states in which the object sets itself up and accesses
disk for the object metadata:

 (2) State FSCACHE_OBJECT_LOOKING_UP.

     Look up the object on disk, using the parent as a starting point.
     FS-Cache expects the cache backend to probe the cache to see whether this
     object is represented there, and if it is, to see if it's valid (coherency
     management).

     The cache should call fscache_object_lookup_negative() to indicate lookup
     failure for whatever reason, and should call fscache_obtained_object() to
     indicate success.

     At the completion of lookup, FS-Cache will let the netfs go ahead with
     read operations, no matter whether the file is yet cached.  If not yet
     cached, read operations will be immediately rejected with ENODATA until
     the first known page is uncached - as to that point there can be no data
     to be read out of the cache for that file that isn't currently also held
     in the pagecache.

 (3) State FSCACHE_OBJECT_CREATING.

     Create an object on disk, using the parent as a starting point.  This
     happens if the lookup failed to find the object, or if the object's
     coherency data indicated what's on disk is out of date.  In this state,
     FS-Cache expects the cache to create

     The cache should call fscache_obtained_object() if creation completes
     successfully, fscache_object_lookup_negative() otherwise.

     At the completion of creation, FS-Cache will start processing write
     operations the netfs has queued for an object.  If creation failed, the
     write ops will be transparently discarded, and nothing recorded in the
     cache.

There are some normal running states in which the object spends its time
servicing netfs requests:

 (4) State FSCACHE_OBJECT_AVAILABLE.

     A transient state in which pending operations are started, child objects
     are permitted to advance from FSCACHE_OBJECT_INIT state, and temporary
     lookup data is freed.

 (5) State FSCACHE_OBJECT_ACTIVE.

     The normal running state.  In this state, requests the netfs makes will be
     passed on to the cache.

 (6) State FSCACHE_OBJECT_UPDATING.

     The state machine comes here to update the object in the cache from the
     netfs's records.  This involves updating the auxiliary data that is used
     to maintain coherency.

And there are terminal states in which an object cleans itself up, deallocates
memory and potentially deletes stuff from disk:

 (7) State FSCACHE_OBJECT_LC_DYING.

     The object comes here if it is dying because of a lookup or creation
     error.  This would be due to a disk error or system error of some sort.
     Temporary data is cleaned up, and the parent is released.

 (8) State FSCACHE_OBJECT_DYING.

     The object comes here if it is dying due to an error, because its parent
     cookie has been relinquished by the netfs or because the cache is being
     withdrawn.

     Any child objects waiting on this one are given CPU time so that they too
     can destroy themselves.  This object waits for all its children to go away
     before advancing to the next state.

 (9) State FSCACHE_OBJECT_ABORT_INIT.

     The object comes to this state if it was waiting on its parent in
     FSCACHE_OBJECT_INIT, but its parent died.  The object will destroy itself
     so that the parent may proceed from the FSCACHE_OBJECT_DYING state.

(10) State FSCACHE_OBJECT_RELEASING.
(11) State FSCACHE_OBJECT_RECYCLING.

     The object comes to one of these two states when dying once it is rid of
     all its children, if it is dying because the netfs relinquished its
     cookie.  In the first state, the cached data is expected to persist, and
     in the second it will be deleted.

(12) State FSCACHE_OBJECT_WITHDRAWING.

     The object transits to this state if the cache decides it wants to
     withdraw the object from service, perhaps to make space, but also due to
     error or just because the whole cache is being withdrawn.

(13) State FSCACHE_OBJECT_DEAD.

     The object transits to this state when the in-memory object record is
     ready to be deleted.  The object processor shouldn't ever see an object in
     this state.

THE SET OF EVENTS
-----------------

There are a number of events that can be raised to an object state machine:

 (*) FSCACHE_OBJECT_EV_UPDATE

     The netfs requested that an object be updated.  The state machine will ask
     the cache backend to update the object, and the cache backend will ask the
     netfs for details of the change through its cookie definition ops.

 (*) FSCACHE_OBJECT_EV_CLEARED

     This is signalled in two circumstances:

     (a) when an object's last child object is dropped and

     (b) when the last operation outstanding on an object is completed.

     This is used to proceed from the dying state.

 (*) FSCACHE_OBJECT_EV_ERROR

     This is signalled when an I/O error occurs during the processing of some
     object.

 (*) FSCACHE_OBJECT_EV_RELEASE
 (*) FSCACHE_OBJECT_EV_RETIRE

     These are signalled when the netfs relinquishes a cookie it was using.
     The event selected depends on whether the netfs asks for the backing
     object to be retired (deleted) or retained.

 (*) FSCACHE_OBJECT_EV_WITHDRAW

     This is signalled when the cache backend wants to withdraw an object.
     This means that the object will have to be detached from the netfs's
     cookie.

Because the withdrawing releasing/retiring events are all handled by the object
state machine, it doesn't matter if there's a collision with both ends trying
to sever the connection at the same time.  The state machine can just pick
which one it wants to honour, and that effects the other.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Steve Dickson <steved@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Tested-by: Daire Byrne <Daire.Byrne@framestore.com>
2009-04-03 16:42:38 +01:00
David Howells 7394daa8c6 FS-Cache: Add use of /proc and presentation of statistics
Make FS-Cache create its /proc interface and present various statistical
information through it.  Also provide the functions for updating this
information.

These features are enabled by:

	CONFIG_FSCACHE_PROC
	CONFIG_FSCACHE_STATS
	CONFIG_FSCACHE_HISTOGRAM

The /proc directory for FS-Cache is also exported so that caching modules can
add their own statistics there too.

The FS-Cache module is loadable at this point, and the statistics files can be
examined by userspace:

	cat /proc/fs/fscache/stats
	cat /proc/fs/fscache/histogram

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Steve Dickson <steved@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Tested-by: Daire Byrne <Daire.Byrne@framestore.com>
2009-04-03 16:42:37 +01:00
David Howells 0dfc41d1ef FS-Cache: Add the FS-Cache cache backend API and documentation
Add the API for a generic facility (FS-Cache) by which caches may declare them
selves open for business, and may obtain work to be done from network
filesystems.  The header file is included by:

	#include <linux/fscache-cache.h>

Documentation for the API is also added to:

	Documentation/filesystems/caching/backend-api.txt

This API is not usable without the implementation of the utility functions
which will be added in further patches.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Steve Dickson <steved@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Tested-by: Daire Byrne <Daire.Byrne@framestore.com>
2009-04-03 16:42:36 +01:00
David Howells 2d6fff6370 FS-Cache: Add the FS-Cache netfs API and documentation
Add the API for a generic facility (FS-Cache) by which filesystems (such as AFS
or NFS) may call on local caching capabilities without having to know anything
about how the cache works, or even if there is a cache:

	+---------+
	|         |                        +--------------+
	|   NFS   |--+                     |              |
	|         |  |                 +-->|   CacheFS    |
	+---------+  |   +----------+  |   |  /dev/hda5   |
	             |   |          |  |   +--------------+
	+---------+  +-->|          |  |
	|         |      |          |--+
	|   AFS   |----->| FS-Cache |
	|         |      |          |--+
	+---------+  +-->|          |  |
	             |   |          |  |   +--------------+
	+---------+  |   +----------+  |   |              |
	|         |  |                 +-->|  CacheFiles  |
	|  ISOFS  |--+                     |  /var/cache  |
	|         |                        +--------------+
	+---------+

General documentation and documentation of the netfs specific API are provided
in addition to the header files.

As this patch stands, it is possible to build a filesystem against the facility
and attempt to use it.  All that will happen is that all requests will be
immediately denied as if no cache is present.

Further patches will implement the core of the facility.  The facility will
transfer requests from networking filesystems to appropriate caches if
possible, or else gracefully deny them.

If this facility is disabled in the kernel configuration, then all its
operations will trivially reduce to nothing during compilation.

WHY NOT I_MAPPING?
==================

I have added my own API to implement caching rather than using i_mapping to do
this for a number of reasons.  These have been discussed a lot on the LKML and
CacheFS mailing lists, but to summarise the basics:

 (1) Most filesystems don't do hole reportage.  Holes in files are treated as
     blocks of zeros and can't be distinguished otherwise, making it difficult
     to distinguish blocks that have been read from the network and cached from
     those that haven't.

 (2) The backing inode must be fully populated before being exposed to
     userspace through the main inode because the VM/VFS goes directly to the
     backing inode and does not interrogate the front inode's VM ops.

     Therefore:

     (a) The backing inode must fit entirely within the cache.

     (b) All backed files currently open must fit entirely within the cache at
     	 the same time.

     (c) A working set of files in total larger than the cache may not be
     	 cached.

     (d) A file may not grow larger than the available space in the cache.

     (e) A file that's open and cached, and remotely grows larger than the
     	 cache is potentially stuffed.

 (3) Writes go to the backing filesystem, and can only be transferred to the
     network when the file is closed.

 (4) There's no record of what changes have been made, so the whole file must
     be written back.

 (5) The pages belong to the backing filesystem, and all metadata associated
     with that page are relevant only to the backing filesystem, and not
     anything stacked atop it.

OVERVIEW
========

FS-Cache provides (or will provide) the following facilities:

 (1) Caches can be added / removed at any time, even whilst in use.

 (2) Adds a facility by which tags can be used to refer to caches, even if
     they're not available yet.

 (3) More than one cache can be used at once.  Caches can be selected
     explicitly by use of tags.

 (4) The netfs is provided with an interface that allows either party to
     withdraw caching facilities from a file (required for (1)).

 (5) A netfs may annotate cache objects that belongs to it.  This permits the
     storage of coherency maintenance data.

 (6) Cache objects will be pinnable and space reservations will be possible.

 (7) The interface to the netfs returns as few errors as possible, preferring
     rather to let the netfs remain oblivious.

 (8) Cookies are used to represent indices, files and other objects to the
     netfs.  The simplest cookie is just a NULL pointer - indicating nothing
     cached there.

 (9) The netfs is allowed to propose - dynamically - any index hierarchy it
     desires, though it must be aware that the index search function is
     recursive, stack space is limited, and indices can only be children of
     indices.

(10) Indices can be used to group files together to reduce key size and to make
     group invalidation easier.  The use of indices may make lookup quicker,
     but that's cache dependent.

(11) Data I/O is effectively done directly to and from the netfs's pages.  The
     netfs indicates that page A is at index B of the data-file represented by
     cookie C, and that it should be read or written.  The cache backend may or
     may not start I/O on that page, but if it does, a netfs callback will be
     invoked to indicate completion.  The I/O may be either synchronous or
     asynchronous.

(12) Cookies can be "retired" upon release.  At this point FS-Cache will mark
     them as obsolete and the index hierarchy rooted at that point will get
     recycled.

(13) The netfs provides a "match" function for index searches.  In addition to
     saying whether a match was made or not, this can also specify that an
     entry should be updated or deleted.

FS-Cache maintains a virtual index tree in which all indices, files, objects
and pages are kept.  Bits of this tree may actually reside in one or more
caches.

                                           FSDEF
                                             |
                        +------------------------------------+
                        |                                    |
                       NFS                                  AFS
                        |                                    |
           +--------------------------+                +-----------+
           |                          |                |           |
        homedir                     mirror          afs.org   redhat.com
           |                          |                            |
     +------------+           +---------------+              +----------+
     |            |           |               |              |          |
   00001        00002       00007           00125        vol00001   vol00002
     |            |           |               |                         |
 +---+---+     +-----+      +---+      +------+------+            +-----+----+
 |   |   |     |     |      |   |      |      |      |            |     |    |
PG0 PG1 PG2   PG0  XATTR   PG0 PG1   DIRENT DIRENT DIRENT        R/W   R/O  Bak
                     |                                            |
                    PG0                                       +-------+
                                                              |       |
                                                            00001   00003
                                                              |
                                                          +---+---+
                                                          |   |   |
                                                         PG0 PG1 PG2

In the example above, two netfs's can be seen to be backed: NFS and AFS.  These
have different index hierarchies:

 (*) The NFS primary index will probably contain per-server indices.  Each
     server index is indexed by NFS file handles to get data file objects.
     Each data file objects can have an array of pages, but may also have
     further child objects, such as extended attributes and directory entries.
     Extended attribute objects themselves have page-array contents.

 (*) The AFS primary index contains per-cell indices.  Each cell index contains
     per-logical-volume indices.  Each of volume index contains up to three
     indices for the read-write, read-only and backup mirrors of those volumes.
     Each of these contains vnode data file objects, each of which contains an
     array of pages.

The very top index is the FS-Cache master index in which individual netfs's
have entries.

Any index object may reside in more than one cache, provided it only has index
children.  Any index with non-index object children will be assumed to only
reside in one cache.

The FS-Cache overview can be found in:

	Documentation/filesystems/caching/fscache.txt

The netfs API to FS-Cache can be found in:

	Documentation/filesystems/caching/netfs-api.txt

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Steve Dickson <steved@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Tested-by: Daire Byrne <Daire.Byrne@framestore.com>
2009-04-03 16:42:36 +01:00
Shen Feng 760df93ecd documentation: update Documentation/filesystem/proc.txt and Documentation/sysctls
Now /proc/sys is described in many places and much information is
redundant.  This patch updates the proc.txt and move the /proc/sys
desciption out to the files in Documentation/sysctls.

Details are:

merge
-  2.1  /proc/sys/fs - File system data
-  2.11 /proc/sys/fs/mqueue - POSIX message queues filesystem
-  2.17 /proc/sys/fs/epoll - Configuration options for the epoll interface
with Documentation/sysctls/fs.txt.

remove
-  2.2  /proc/sys/fs/binfmt_misc - Miscellaneous binary formats
since it's not better then the Documentation/binfmt_misc.txt.

merge
-  2.3  /proc/sys/kernel - general kernel parameters
with Documentation/sysctls/kernel.txt

remove
-  2.5  /proc/sys/dev - Device specific parameters
since it's obsolete the sysfs is used now.

remove
-  2.6  /proc/sys/sunrpc - Remote procedure calls
since it's not better then the Documentation/sysctls/sunrpc.txt

move
-  2.7  /proc/sys/net - Networking stuff
-  2.9  Appletalk
-  2.10 IPX
to newly created Documentation/sysctls/net.txt.

remove
-  2.8  /proc/sys/net/ipv4 - IPV4 settings
since it's not better then the Documentation/networking/ip-sysctl.txt.

add
- Chapter 3 Per-Process Parameters
to descibe /proc/<pid>/xxx parameters.

Signed-off-by: Shen Feng <shen@cn.fujitsu.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-02 19:04:53 -07:00
Marcin Slusarz 7ac9bcd5da udf: implement mode and dmode mounting options
"dmode" allows overriding permissions of directories and
"mode" allows overriding permissions of files.

Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jan Kara <jack@suse.cz>
2009-04-02 12:29:50 +02:00
Linus Torvalds 395d73413c Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (33 commits)
  ext4: Regularize mount options
  ext4: fix locking typo in mballoc which could cause soft lockup hangs
  ext4: fix typo which causes a memory leak on error path
  jbd2: Update locking coments
  ext4: Rename pa_linear to pa_type
  ext4: add checks of block references for non-extent inodes
  ext4: Check for an valid i_mode when reading the inode from disk
  ext4: Use WRITE_SYNC for commits which are caused by fsync()
  ext4: Add auto_da_alloc mount option
  ext4: Use struct flex_groups to calculate get_orlov_stats()
  ext4: Use atomic_t's in struct flex_groups
  ext4: remove /proc tuning knobs
  ext4: Add sysfs support
  ext4: Track lifetime disk writes
  ext4: Fix discard of inode prealloc space with delayed allocation.
  ext4: Automatically allocate delay allocated blocks on rename
  ext4: Automatically allocate delay allocated blocks on close
  ext4: add EXT4_IOC_ALLOC_DA_BLKS ioctl
  ext4: Simplify delalloc code by removing mpage_da_writepages()
  ext4: Save stack space by removing fake buffer heads
  ...
2009-04-01 10:57:49 -07:00
Linus Torvalds e76e5b2c66 Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (88 commits)
  PCI: fix HT MSI mapping fix
  PCI: don't enable too much HT MSI mapping
  x86/PCI: make pci=lastbus=255 work when acpi is on
  PCI: save and restore PCIe 2.0 registers
  PCI: update fakephp for bus_id removal
  PCI: fix kernel oops on bridge removal
  PCI: fix conflict between SR-IOV and config space sizing
  powerpc/PCI: include pci.h in powerpc MSI implementation
  PCI Hotplug: schedule fakephp for feature removal
  PCI Hotplug: rename legacy_fakephp to fakephp
  PCI Hotplug: restore fakephp interface with complete reimplementation
  PCI: Introduce /sys/bus/pci/devices/.../rescan
  PCI: Introduce /sys/bus/pci/devices/.../remove
  PCI: Introduce /sys/bus/pci/rescan
  PCI: Introduce pci_rescan_bus()
  PCI: do not enable bridges more than once
  PCI: do not initialize bridges more than once
  PCI: always scan child buses
  PCI: pci_scan_slot() returns newly found devices
  PCI: don't scan existing devices
  ...

Fix trivial append-only conflict in Documentation/feature-removal-schedule.txt
2009-04-01 09:47:12 -07:00
Nick Piggin c2ec175c39 mm: page_mkwrite change prototype to match fault
Change the page_mkwrite prototype to take a struct vm_fault, and return
VM_FAULT_xxx flags.  There should be no functional change.

This makes it possible to return much more detailed error information to
the VM (and also can provide more information eg.  virtual_address to the
driver, which might be important in some special cases).

This is required for a subsequent fix.  And will also make it easier to
merge page_mkwrite() with fault() in future.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <joel.becker@oracle.com>
Cc: Artem Bityutskiy <dedekind@infradead.org>
Cc: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01 08:59:14 -07:00
Boaz Harrosh 214c8adb87 exofs: Documentation
Added some documentation in exofs.txt, as well as a BUGS file.

For further reading, operation instructions, example scripts
and up to date infomation and code please see:
http://open-osd.org

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
2009-03-31 19:44:38 +03:00
Pavel Machek e3375ac767 trivial: document ext3 semantics of 'ro' option a bit better
ext3 has quite unexpected semantics or "ro" and defaults are
not what they are documented to be, due to mkfs override.

Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-03-30 15:21:56 +02:00
Theodore Ts'o 06705bff91 ext4: Regularize mount options
Add support for using the mount options "barrier" and "nobarrier", and
"auto_da_alloc" and "noauto_da_alloc", which is more consistent than
"barrier=<0|1>" or "auto_da_alloc=<0|1>".  Most other ext3/ext4 mount
options use the foo/nofoo naming convention.  We allow the old forms
of these mount options for backwards compatibility.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-28 10:59:57 -04:00
Greg Banks b5cbc369db Document /proc/fs/nfsd/pool_stats
Document the format and semantics of the /proc/fs/nfsd/pool_stats file.

Signed-off-by: Greg Banks <gnb@sgi.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-03-27 19:24:27 -04:00
Linus Torvalds 8e9d208972 Merge branch 'bkl-removal' of git://git.lwn.net/linux-2.6
* 'bkl-removal' of git://git.lwn.net/linux-2.6:
  Rationalize fasync return values
  Move FASYNC bit handling to f_op->fasync()
  Use f_lock to protect f_flags
  Rename struct file->f_ep_lock
2009-03-26 16:14:02 -07:00
Jody McIntyre 1db4b2d221 trivial: fix orphan dates in ext2 documentation
Revert the change to the orphan dates of Windows 95, DOS, compression.
Add a new orphan date for OS/2.

Signed-off-by: Jody McIntyre <scjody@sun.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-23 14:21:26 -07:00
Linus Torvalds d56ffd38a9 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (32 commits)
  ucc_geth: Fix oops when using fixed-link support
  dm9000: locking bugfix
  net: update dnet.c for bus_id removal
  dnet: DNET should depend on HAS_IOMEM
  dca: add missing copyright/license headers
  nl80211: Check that function pointer != NULL before using it
  sungem: missing net_device_ops
  be2net: fix to restore vlan ids into BE2 during a IF DOWN->UP cycle
  be2net: replenish when posting to rx-queue is starved in out of mem conditions
  bas_gigaset: correctly allocate USB interrupt transfer buffer
  smsc911x: reset last known duplex and carrier on open
  sh_eth: Fix mistake of the address of SH7763
  sh_eth: Change handling of IRQ
  netns: oops in ip[6]_frag_reasm incrementing stats
  net: kfree(napi->skb) => kfree_skb
  net: fix sctp breakage
  ipv6: fix display of local and remote sit endpoints
  net: Document /proc/sys/net/core/netdev_budget
  tulip: fix crash on iface up with shirq debug
  virtio_net: Make virtio_net support carrier detection
  ...
2009-03-23 09:25:58 -07:00
Alex Chiang 77c27c7b49 PCI: Introduce /sys/bus/pci/devices/.../remove
This patch adds an attribute named "remove" to a PCI device's sysfs
directory.  Writing a non-zero value to this attribute will remove the PCI
device and any children of it.

Trent Piepho wrote the original implementation and documentation.

Thanks to Vegard Nossum for testing under kmemcheck and finding locking
issues with the sysfs interface.

Cc: Trent Piepho <xyzzy@speakeasy.org>
Tested-by: Vegard Nossum <vegard.nossum@gmail.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-20 14:58:48 -07:00
Stanislaw Gruszka e9c6a586f5 net: Document /proc/sys/net/core/netdev_budget
The NAPI poll parameter netdev_budget is not documented in
kernel-docs. Since it may have a substantial effect on at least some
network loads, it should be.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> 
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-18 18:51:06 -07:00
Jonathan Corbet 76398425bb Move FASYNC bit handling to f_op->fasync()
Removing the BKL from FASYNC handling ran into the challenge of keeping the
setting of the FASYNC bit in filp->f_flags atomic with regard to calls to
the underlying fasync() function.  Andi Kleen suggested moving the handling
of that bit into fasync(); this patch does exactly that.  As a result, we
have a couple of internal API changes: fasync() must now manage the FASYNC
bit, and it will be called without the BKL held.

As it happens, every fasync() implementation in the kernel with one
exception calls fasync_helper().  So, if we make fasync_helper() set the
FASYNC bit, we can avoid making any changes to the other fasync()
functions - as long as those functions, themselves, have proper locking.
Most fasync() implementations do nothing but call fasync_helper() - which
has its own lock - so they are easily verified as correct.  The BKL had
already been pushed down into the rest.

The networking code has its own version of fasync_helper(), so that code
has been augmented with explicit FASYNC bit handling.

Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: David Miller <davem@davemloft.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2009-03-16 08:32:27 -06:00
Jody McIntyre ab03eca8d4 trivial: fix bad links in the ext2 and ext3 documentation
Trivial patch to fix bad links in the ext2 and ext3 documentation.

Signed-off-by: Jody McIntyre <scjody@sun.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-12 16:24:25 -07:00
Phillip Lougher edf2e2811e Squashfs: fix documentation typo, Cramfs filesystem limit is 256 MiB
Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
2009-03-05 00:40:13 +00:00
Theodore Ts'o b713a5ec55 ext4: remove /proc tuning knobs
Remove tuning knobs in /proc/fs/ext4/<dev/* since they have been
replaced by knobs in sysfs at /sys/fs/ext4/<dev>/*.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-31 09:11:14 -04:00
Theodore Ts'o 722bde6875 ext4: Add fine print for the 32000 subdirectory limit
Some poeple are reading the ext4 feature list too literally and create
dubious test cases involving very long filenames and 1k blocksize and
then complain when they run into an htree-imposed limit.  So add fine
print to the "fix 32000 subdirectory limit" ext4 feature.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-23 00:51:57 -05:00
Mike Murphy f8a1af6bbc PATCH [2/2] Documentation/filesystems/sysfs.txt: fix descriptions of device attributes
Fix descriptions of device attributes to be consistent with the actual
implementations in include/linux/device.h

Signed-off-by: Mike Murphy <mamurph[at]cs.clemson.edu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-22 09:28:15 -08:00
Timothy S. Nelson 97c44836cd PCI: return error on failure to read PCI ROMs
This patch makes the ROM reading code return an error to user space if
the size of the ROM read is equal to 0.

The patch also emits a warnings if the contents of the ROM are invalid,
and documents the effects of the "enable" file on ROM reading.

Signed-off-by: Timothy S. Nelson <wayland@wayland.id.au>
Acked-by: Alex Villacis-Lasso <a_villacis@palosanto.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-02-04 16:58:41 -08:00
Linus Torvalds f96c08e8c5 Merge branch 'linux-next' of git://git.infradead.org/ubifs-2.6
* 'linux-next' of git://git.infradead.org/ubifs-2.6:
  UBIFS: remove fast unmounting
  UBIFS: return sensible error codes
  UBIFS: remount ro fixes
  UBIFS: spelling fix 'date' -> 'data'
  UBIFS: sync wbufs after syncing inodes and pages
  UBIFS: fix LPT out-of-space bug (again)
  UBIFS: fix no_chk_data_crc
  UBIFS: fix assertions
  UBIFS: ensure orphan area head is initialized
  UBIFS: always clean up GC LEB space
  UBIFS: add re-mount debugging checks
  UBIFS: fix LEB list freeing
  UBIFS: simplify locking
  UBIFS: document dark_wm and dead_wm better
  UBIFS: do not treat all data as short term
  UBIFS: constify operations
  UBIFS: do not commit twice
2009-02-03 16:52:44 -08:00
Evgeniy Polyakov 9e9e3cbc62 mm: OOM documentation update
Signed-off-by: Evgeniy Polyakov <zbr@ioremap.net>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-29 18:04:43 -08:00
Artem Bityutskiy 27ad279933 UBIFS: remove fast unmounting
This UBIFS feature has never worked properly, and it was a mistake
to add it because we simply have no use-cases. So, lets still accept
the fast_unmount mount option, but ignore it. This does not change
much, because UBIFS commit in sync_fs anyway, and sync_fs is called
while unmounting.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2009-01-29 16:34:30 +02:00
James Lentini 096abd7703 update port number in NFS/RDMA documentation
Update the NFS/RDMA documentation to use the new port number assigned
by IANA.

Signed-off-by: James Lentini <jlentini@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-27 17:20:14 -05:00
Peter W Morreale db0fb1848a Update of Documentation: vm.txt and proc.txt
Update Documentation/sysctl/vm.txt and Documentation/filesystems/proc.txt.
 More specifically, the section on /proc/sys/vm in
Documentation/filesystems/proc.txt was removed and a link to
Documentation/sysctl/vm.txt added.

Most of the verbiage from proc.txt was simply moved in vm.txt, with new
addtional text for "swappiness" and "stat_interval".

Signed-off-by: Peter W Morreale <pmorreale@novell.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-15 16:39:35 -08:00
Takashi Sato c4be0c1dc4 filesystem freeze: add error handling of write_super_lockfs/unlockfs
Currently, ext3 in mainline Linux doesn't have the freeze feature which
suspends write requests.  So, we cannot take a backup which keeps the
filesystem's consistency with the storage device's features (snapshot and
replication) while it is mounted.

In many case, a commercial filesystem (e.g.  VxFS) has the freeze feature
and it would be used to get the consistent backup.

If Linux's standard filesystem ext3 has the freeze feature, we can do it
without a commercial filesystem.

So I have implemented the ioctls of the freeze feature.
I think we can take the consistent backup with the following steps.
1. Freeze the filesystem with the freeze ioctl.
2. Separate the replication volume or create the snapshot
   with the storage device's feature.
3. Unfreeze the filesystem with the unfreeze ioctl.
4. Take the backup from the separated replication volume
   or the snapshot.

This patch:

VFS:
Changed the type of write_super_lockfs and unlockfs from "void"
to "int" so that they can return an error.
Rename write_super_lockfs and unlockfs of the super block operation
freeze_fs and unfreeze_fs to avoid a confusion.

ext3, ext4, xfs, gfs2, jfs:
Changed the type of write_super_lockfs and unlockfs from "void"
to "int" so that write_super_lockfs returns an error if needed,
and unlockfs always returns 0.

reiserfs:
Changed the type of write_super_lockfs and unlockfs from "void"
to "int" so that they always return 0 (success) to keep a current behavior.

Signed-off-by: Takashi Sato <t-sato@yk.jp.nec.com>
Signed-off-by: Masayuki Hamaguchi <m-hamaguchi@ys.jp.nec.com>
Cc: <xfs-masters@oss.sgi.com>
Cc: <linux-ext4@vger.kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Kleikamp <shaggy@austin.ibm.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Alasdair G Kergon <agk@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-09 16:54:42 -08:00
Linus Torvalds 31aeb6c815 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-linus
* git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-linus:
  MAINTAINERS: squashfs entry
  Squashfs: documentation
  Squashfs: initrd support
  Squashfs: Kconfig entry
  Squashfs: Makefiles
  Squashfs: header files
  Squashfs: block operations
  Squashfs: cache operations
  Squashfs: uid/gid lookup operations
  Squashfs: fragment block operations
  Squashfs: export operations
  Squashfs: super block operations
  Squashfs: symlink operations
  Squashfs: regular file operations
  Squashfs: directory readdir operations
  Squashfs: directory lookup operations
  Squashfs: inode operations
2009-01-09 15:18:49 -08:00
Linus Torvalds 73d59314e6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: (864 commits)
  Btrfs: explicitly mark the tree log root for writeback
  Btrfs: Drop the hardware crc32c asm code
  Btrfs: Add Documentation/filesystem/btrfs.txt, remove old COPYING
  Btrfs: kmap_atomic(KM_USER0) is safe for btrfs_readpage_end_io_hook
  Btrfs: Don't use kmap_atomic(..., KM_IRQ0) during checksum verifies
  Btrfs: tree logging checksum fixes
  Btrfs: don't change file extent's ram_bytes in btrfs_drop_extents
  Btrfs: Use btrfs_join_transaction to avoid deadlocks during snapshot creation
  Btrfs: drop remaining LINUX_KERNEL_VERSION checks and compat code
  Btrfs: drop EXPORT symbols from extent_io.c
  Btrfs: Fix checkpatch.pl warnings
  Btrfs: Fix free block discard calls down to the block layer
  Btrfs: avoid orphan inode caused by log replay
  Btrfs: avoid potential super block corruption
  Btrfs: do not call kfree if kmalloc failed in btrfs_sysfs_add_super
  Btrfs: fix a memory leak in btrfs_get_sb
  Btrfs: Fix typo in clear_state_cb
  Btrfs: Fix memset length in btrfs_file_write
  Btrfs: update directory's size when creating subvol/snapshot
  Btrfs: add permission checks to the ioctls
  ...
2009-01-09 13:01:38 -08:00
Linus Torvalds 2150edc6c5 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (57 commits)
  jbd2: Fix oops in jbd2_journal_init_inode() on corrupted fs
  ext4: Remove "extents" mount option
  block: Add Kconfig help which notes that ext4 needs CONFIG_LBD
  ext4: Make printk's consistently prefixed with "EXT4-fs: "
  ext4: Add sanity checks for the superblock before mounting the filesystem
  ext4: Add mount option to set kjournald's I/O priority
  jbd2: Submit writes to the journal using WRITE_SYNC
  jbd2: Add pid and journal device name to the "kjournald2 starting" message
  ext4: Add markers for better debuggability
  ext4: Remove code to create the journal inode
  ext4: provide function to release metadata pages under memory pressure
  ext3: provide function to release metadata pages under memory pressure
  add releasepage hooks to block devices which can be used by file systems
  ext4: Fix s_dirty_blocks_counter if block allocation failed with nodelalloc
  ext4: Init the complete page while building buddy cache
  ext4: Don't allow new groups to be added during block allocation
  ext4: mark the blocks/inode bitmap beyond end of group as used
  ext4: Use new buffer_head flag to check uninit group bitmaps initialization
  ext4: Fix the race between read_inode_bitmap() and ext4_new_inode()
  ext4: code cleanup
  ...
2009-01-08 17:14:59 -08:00
Linus Torvalds a0c9f240a9 Merge branch 'proc-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/adobriyan/proc
* 'proc-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/adobriyan/proc:
  proc: remove write-only variable in proc_pident_lookup()
  proc: fix sparse warning
  proc: add /proc/*/stack
  proc: remove '##' usage
  proc: remove useless WARN_ONs
  proc: stop using BKL
2009-01-07 12:01:06 -08:00
David Woodhouse 709ac06a14 Btrfs: Add Documentation/filesystem/btrfs.txt, remove old COPYING
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-01-07 09:54:24 -05:00
Tejun Heo 5f820f648c poll: allow f_op->poll to sleep
f_op->poll is the only vfs operation which is not allowed to sleep.  It's
because poll and select implementation used task state to synchronize
against wake ups, which doesn't have to be the case anymore as wait/wake
interface can now use custom wake up functions.  The non-sleep restriction
can be a bit tricky because ->poll is not called from an atomic context
and the result of accidentally sleeping in ->poll only shows up as
temporary busy looping when the timing is right or rather wrong.

This patch converts poll/select to use custom wake up function and use
separate triggered variable to synchronize against wake up events.  The
only added overhead is an extra function call during wake up and
negligible.

This patch removes the one non-sleep exception from vfs locking rules and
is beneficial to userland filesystem implementations like FUSE, 9p or
peculiar fs like spufs as it's very difficult for those to implement
non-sleeping poll method.

While at it, make the following cosmetic changes to make poll.h and
select.c checkpatch friendly.

* s/type * symbol/type *symbol/		   : three places in poll.h
* remove blank line before EXPORT_SYMBOL() : two places in select.c

Oleg: spotted missing barrier in poll_schedule_timeout()
Davide: spotted missing write barrier in pollwake()

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Davide Libenzi <davidel@xmailserver.org>
Cc: Brad Boyer <flar@allandria.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Roland McGrath <roland@redhat.com>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Davide Libenzi <davidel@xmailserver.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:12 -08:00
David Rientjes 2da02997e0 mm: add dirty_background_bytes and dirty_bytes sysctls
This change introduces two new sysctls to /proc/sys/vm:
dirty_background_bytes and dirty_bytes.

dirty_background_bytes is the counterpart to dirty_background_ratio and
dirty_bytes is the counterpart to dirty_ratio.

With growing memory capacities of individual machines, it's no longer
sufficient to specify dirty thresholds as a percentage of the amount of
dirtyable memory over the entire system.

dirty_background_bytes and dirty_bytes specify quantities of memory, in
bytes, that represent the dirty limits for the entire system.  If either
of these values is set, its value represents the amount of dirty memory
that is needed to commence either background or direct writeback.

When a `bytes' or `ratio' file is written, its counterpart becomes a
function of the written value.  For example, if dirty_bytes is written to
be 8096, 8K of memory is required to commence direct writeback.
dirty_ratio is then functionally equivalent to 8K / the amount of
dirtyable memory:

	dirtyable_memory = free pages + mapped pages + file cache

	dirty_background_bytes = dirty_background_ratio * dirtyable_memory
		-or-
	dirty_background_ratio = dirty_background_bytes / dirtyable_memory

		AND

	dirty_bytes = dirty_ratio * dirtyable_memory
		-or-
	dirty_ratio = dirty_bytes / dirtyable_memory

Only one of dirty_background_bytes and dirty_background_ratio may be
specified at a time, and only one of dirty_bytes and dirty_ratio may be
specified.  When one sysctl is written, the other appears as 0 when read.

The `bytes' files operate on a page size granularity since dirty limits
are compared with ZVC values, which are in page units.

Prior to this change, the minimum dirty_ratio was 5 as implemented by
get_dirty_limits() although /proc/sys/vm/dirty_ratio would show any user
written value between 0 and 100.  This restriction is maintained, but
dirty_bytes has a lower limit of only one page.

Also prior to this change, the dirty_background_ratio could not equal or
exceed dirty_ratio.  This restriction is maintained in addition to
restricting dirty_background_bytes.  If either background threshold equals
or exceeds that of the dirty threshold, it is implicitly set to half the
dirty threshold.

Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Andrea Righi <righi.andrea@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:03 -08:00
Theodore Ts'o 83982b6f47 ext4: Remove "extents" mount option
This mount option is largely superfluous, and in fact the way it was
implemented was buggy; if a filesystem which did not have the extents
feature flag was mounted -o extents, the filesystem would attempt to
create and use extents-based file even though the extents feature flag
was not eabled.  The simplest thing to do is to nuke the mount option
entirely.  It's not all that useful to force the non-creation of new
extent-based files if the filesystem can support it.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-01-06 14:53:16 -05:00
Theodore Ts'o b3881f74b3 ext4: Add mount option to set kjournald's I/O priority
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jens Axboe <jens.axboe@oracle.com>
2009-01-05 22:46:26 -05:00
Tiger Yang a68979b857 ocfs2: add mount option and Kconfig option for acl
This patch adds the Kconfig option "CONFIG_OCFS2_FS_POSIX_ACL"
and mount options "acl" to enable acls in Ocfs2.

Signed-off-by: Tiger Yang <tiger.yang@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-01-05 08:36:52 -08:00
Ken Chen 2ec220e27f proc: add /proc/*/stack
/proc/*/stack adds the ability to query a task's stack trace. It is more
useful than /proc/*/wchan as it provides full stack trace instead of single
depth. Example output:

	$ cat /proc/self/stack
	[<c010a271>] save_stack_trace_tsk+0x17/0x35
	[<c01827b4>] proc_pid_stack+0x4a/0x76
	[<c018312d>] proc_single_show+0x4a/0x5e
	[<c016bdec>] seq_read+0xf3/0x29f
	[<c015a004>] vfs_read+0x6d/0x91
	[<c015a0c1>] sys_read+0x3b/0x60
	[<c0102eda>] syscall_call+0x7/0xb
	[<ffffffff>] 0xffffffff

[add save_stack_trace_tsk() on mips, ACK Ralf --adobriyan]
Signed-off-by: Ken Chen <kenchen@google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-01-05 12:27:44 +03:00
Phillip Lougher 9eb425c046 Squashfs: documentation
Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
2009-01-05 08:46:29 +00:00
Theodore Ts'o c319106723 ext4: Remove code to create the journal inode
This code has been obsolete in quite some time, since the supported
method for adding a journal inode is to use tune2fs (or to creating
new filesystem with a journal via mke2fs or mkfs.ext4).

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-01-06 11:14:25 -05:00
Linus Torvalds 8e3bda0863 Merge branch 'linux-next' of git://git.infradead.org/ubifs-2.6
* 'linux-next' of git://git.infradead.org/ubifs-2.6: (33 commits)
  UBIFS: add more useful debugging prints
  UBIFS: print debugging messages properly
  UBIFS: fix numerous spelling mistakes
  UBIFS: allow mounting when short of space
  UBIFS: fix writing uncompressed files
  UBIFS: fix checkpatch.pl warnings
  UBIFS: fix sparse warnings
  UBIFS: simplify make_free_space
  UBIFS: do not lie about used blocks
  UBIFS: restore budg_uncommitted_idx
  UBIFS: always commit on unmount
  UBIFS: use ubi_sync
  UBIFS: always commit in sync_fs
  UBIFS: fix file-system synchronization
  UBIFS: fix constants initialization
  UBIFS: avoid unnecessary calculations
  UBIFS: re-calculate min_idx_size after the commit
  UBIFS: use nicer 64-bit math
  UBIFS: fix available blocks count
  UBIFS: various comment improvements and fixes
  ...
2009-01-02 15:57:47 -08:00
Sukadev Bhattiprolu 784c4d8b1b Document usage of multiple-instances of devpts
Changelog [v2]:
	- Add note indicating strict isolation is not possible unless all
	  mounts of devpts use the 'newinstance' mount option.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02 10:19:36 -08:00
Al Viro 6badd79bd0 kill ->dir_notify()
Remove the hopelessly misguided ->dir_notify().  The only instance (cifs)
has been broken by design from the very beginning; the objects it creates
are never destroyed, keep references to struct file they can outlive, nothing
that could possibly evict them exists on close(2) path *and* no locking
whatsoever is done to prevent races with close(), should the previous, er,
deficiencies someday be dealt with.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-12-31 18:07:43 -05:00
Eric Dumazet fd659fd627 fix f_count description in Documentation/filesystems/files.txt
Documentation/filesystems/files.txt was not updated when
f_count became an atomic_long_t.
atomic_long_inc_not_zero() is now used instead of atomic_inc_not_zero()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-12-31 18:07:42 -05:00
Zhaolei be42c4c433 correct wrong function name of d_put in kernel document and source comment
no function named d_put(), it should be dput().

Impact: fix document and comment, no functionality changed

Signed-off-by: Zhao Lei <zhaolei@cn.fuijtsu.com>
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-12-31 18:07:40 -05:00
Artem Bityutskiy 80736d41f8 UBIFS: fix numerous spelling mistakes
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-12-31 14:13:25 +02:00
Lachlan McIlroy 0a8c5395f9 [XFS] Fix merge failures
Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6

Conflicts:

	fs/xfs/linux-2.6/xfs_cred.h
	fs/xfs/linux-2.6/xfs_globals.h
	fs/xfs/linux-2.6/xfs_ioctl.c
	fs/xfs/xfs_vnodeops.h

Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
2008-12-29 16:47:18 +11:00
Ingo Molnar fa623d1b02 Merge branches 'x86/apic', 'x86/cleanups', 'x86/cpufeature', 'x86/crashdump', 'x86/debug', 'x86/defconfig', 'x86/detect-hyper', 'x86/doc', 'x86/dumpstack', 'x86/early-printk', 'x86/fpu', 'x86/idle', 'x86/io', 'x86/memory-corruption-check', 'x86/microcode', 'x86/mm', 'x86/mtrr', 'x86/nmi-watchdog', 'x86/pat2', 'x86/pci-ioapic-boot-irq-quirks', 'x86/ptrace', 'x86/quirks', 'x86/reboot', 'x86/setup-memory', 'x86/signal', 'x86/sparse-fixes', 'x86/time', 'x86/uv' and 'x86/xen' into x86/core 2008-12-23 16:27:23 +01:00
Lachlan McIlroy 14d676f56f Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 2008-12-05 15:27:43 +11:00
Artem Bityutskiy 553dea4dd5 UBIFS: introduce compression mount options
It is very handy to be able to change default UBIFS compressor
via mount options. Introduce -o compr=<name> mount option support.
Currently only "none", "lzo" and "zlib" compressors are supported.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-12-03 13:14:05 +02:00
Davide Libenzi 7ef9964e6d epoll: introduce resource usage limits
It has been thought that the per-user file descriptors limit would also
limit the resources that a normal user can request via the epoll
interface.  Vegard Nossum reported a very simple program (a modified
version attached) that can make a normal user to request a pretty large
amount of kernel memory, well within the its maximum number of fds.  To
solve such problem, default limits are now imposed, and /proc based
configuration has been introduced.  A new directory has been created,
named /proc/sys/fs/epoll/ and inside there, there are two configuration
points:

  max_user_instances = Maximum number of devices - per user

  max_user_watches   = Maximum number of "watched" fds - per user

The current default for "max_user_watches" limits the memory used by epoll
to store "watches", to 1/32 of the amount of the low RAM.  As example, a
256MB 32bit machine, will have "max_user_watches" set to roughly 90000.
That should be enough to not break existing heavy epoll users.  The
default value for "max_user_instances" is set to 128, that should be
enough too.

This also changes the userspace, because a new error code can now come out
from EPOLL_CTL_ADD (-ENOSPC).  The EMFILE from epoll_create() was already
listed, so that should be ok.

[akpm@linux-foundation.org: use get_current_user()]
Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: <stable@kernel.org>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Reported-by: Vegard Nossum <vegardno@ifi.uio.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-01 19:55:24 -08:00
Mark Fasheh a2eee69b81 ocfs2: Small documentation update
Remove some features from the "not-supported" list that are actually
supported now.

Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-12-01 14:46:49 -08:00
frans 1838e39214 Trivial Documentation/filesystems/ramfs-rootfs-initramfs.txt fix
A very minor patch on ramfs-rootfs-initramfs.txt: update the location
where CONFIG_INITRAMFS_SOURCE lives in menuconfig

Signed-off-by: Frans Meulenbroeks <fransmeulenbroeks@gmail.com>
Acked-by: Rob Landley <rob@landley.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-30 11:40:56 -08:00
Lachlan McIlroy b5a20aa265 Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 2008-11-28 15:23:52 +11:00
Marco Stornelli 084c304980 DOC: update xip method info
xip documentation updated:
- change "get_xip_page" to "get_xip_mem";
- explain changed function parameters

Signed-off-by: Marco Stornelli <marco.stornelli@gmail.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-12 17:17:17 -08:00
Niv Sardi dcd7b4e5c0 Merge branch 'master' of git://oss.sgi.com:8090/xfs/linux-2.6 2008-11-07 15:07:12 +11:00
OGAWA Hirofumi dfc209c006 fat: Fix ATTR_RO for directory
FAT has the ATTR_RO (read-only) attribute. But on Windows, the ATTR_RO
of the directory will be just ignored actually, and is used by only
applications as flag. E.g. it's setted for the customized folder by
Explorer.

http://msdn2.microsoft.com/en-us/library/aa969337.aspx

This adds "rodir" option. If user specified it, ATTR_RO is used as
read-only flag even if it's the directory. Otherwise, inode->i_mode
is not used to hold ATTR_RO (i.e. fat_mode_can_save_ro() returns 0).

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-06 15:41:21 -08:00
Bart Trojanowski 8986ab5963 fat: document additional vfat mount options
While debugging a sync mount regression on vfat I noticed that there were
mount options parsed by the driver that were not documented.

[hirofumi@mail.parknet.co.jp: fix some parts]
Signed-off-by: Bart Trojanowski <bart@jukie.net>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-06 15:41:20 -08:00
Theodore Ts'o 30773840c1 ext4: add fsync batch tuning knobs
Add new mount options, min_batch_time and max_batch_time, which
controls how long the jbd2 layer should wait for additional filesystem
operations to get batched with a synchronous write transaction.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-01-03 20:27:38 -05:00
Theodore Ts'o 8e1a4857cd Update Documentation/filesystems/ext4.txt
Fix paragraph with recommendations on how to tune ext4 for benchmarks.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-01-06 14:53:06 -05:00
Nick Piggin 4e02ed4b4a fs: remove prepare_write/commit_write
Nothing uses prepare_write or commit_write. Remove them from the tree
completely.

[akpm@linux-foundation.org: schedule simple_prepare_write() for unexporting]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-30 11:38:45 -07:00
Aristeu Rozanski 8a1c8eb75b x86, nmi-watchdog: update procfs nmi_watchdog file documentation v2
Impact: improve documentation

This patch updates the /proc/sys/kernel/nmi_watchdog documentation.
Updated: included Randy Dunlap's corrections.

Signed-off-by: Aristeu Rozanski <aris@redhat.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-30 19:07:04 +01:00
Tim Shimmin f3f0d7b026 [XFS] remove restricted chown parameter from xfs linux
On Linux all filesystems are supposed to be operating under Posix'
restricted chown. Restricted chown means it restricts chown to the owner
unless you have CAP_FOWNER.

NOTE: that 2 files outside of fs/xfs have been modified too for this
change.

Reviewed-by: Dave Chinner <david@fromorbit.com>

SGI-PV: 988919

SGI-Modid: 2.6.x-xfs-melb:linux:32413b

Signed-off-by: Tim Shimmin <tes@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
2008-10-30 18:30:09 +11:00
Linus Torvalds 396b122f6a Merge branch 'linux-next' of git://git.infradead.org/ubifs-2.6
* 'linux-next' of git://git.infradead.org/ubifs-2.6: (25 commits)
  UBIFS: fix ubifs_compress commentary
  UBIFS: amend printk
  UBIFS: do not read unnecessary bytes when unpacking bits
  UBIFS: check buffer length when scanning for LPT nodes
  UBIFS: correct condition to eliminate unecessary assignment
  UBIFS: add more debugging messages for LPT
  UBIFS: fix bulk-read handling uptodate pages
  UBIFS: improve garbage collection
  UBIFS: allow for sync_fs when read-only
  UBIFS: commit on sync_fs
  UBIFS: correct comment for commit_on_unmount
  UBIFS: update dbg_dump_inode
  UBIFS: fix commentary
  UBIFS: fix races in bit-fields
  UBIFS: ensure data read beyond i_size is zeroed out correctly
  UBIFS: correct key comparison
  UBIFS: use bit-fields when possible
  UBIFS: check data CRC when in error state
  UBIFS: improve znode splitting rules
  UBIFS: add no_chk_data_crc mount option
  ...
2008-10-20 09:19:03 -07:00
Hidehiro Kawai 0e4fb5e283 ext3: add an option to control error handling on file data
If the journal doesn't abort when it gets an IO error in file data blocks,
the file data corruption will spread silently.  Because most of
applications and commands do buffered writes without fsync(), they don't
notice the IO error.  It's scary for mission critical systems.  On the
other hand, if the journal aborts whenever it gets an IO error in file
data blocks, the system will easily become inoperable.  So this patch
introduces a filesystem option to determine whether it aborts the journal
or just call printk() when it gets an IO error in file data.

If you mount a ext3 fs with data_err=abort option, it aborts on file data
write error.  If you mount it with data_err=ignore, it doesn't abort, just
call printk().  data_err=ignore is the default.

Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Jan Kara <jack@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 08:52:37 -07:00
Andrea Righi 7a6560e025 documentation: clarify dirty_ratio and dirty_background_ratio description
The current documentation of dirty_ratio and dirty_background_ratio is a
bit misleading.

In the documentation we say that they are "a percentage of total system
memory", but the current page writeback policy, intead, is to apply the
percentages to the dirtyable memory, that means free pages + reclaimable
pages.

Better to be more explicit to clarify this concept.

Signed-off-by: Andrea Righi <righi.andrea@gmail.com>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 08:52:32 -07:00
KOSAKI Motohiro e575f111dc coredump_filter: add hugepage dumping
Presently hugepage's vma has a VM_RESERVED flag in order not to be
swapped.  But a VM_RESERVED vma isn't core dumped because this flag is
often used for some kernel vmas (e.g.  vmalloc, sound related).

Thus hugepages are never dumped and it can't be debugged easily.  Many
developers want hugepages to be included into core-dump.

However, We can't read generic VM_RESERVED area because this area is often
IO mapping area.  then these area reading may change device state.  it is
definitly undesiable side-effect.

So adding a hugepage specific bit to the coredump filter is better.  It
will be able to hugepage core dumping and doesn't cause any side-effect to
any i/o devices.

In additional, libhugetlb use hugetlb private mapping pages as anonymous
page.  Then, hugepage private mapping pages should be core dumped by
default.

Then, /proc/[pid]/core_dump_filter has two new bits.

 - bit 5 mean hugetlb private mapping pages are dumped or not. (default: yes)
 - bit 6 mean hugetlb shared mapping pages are dumped or not.  (default: no)

I tested by following method.

% ulimit -c unlimited
% ./crash_hugepage  50
% ./crash_hugepage  50  -p
% ls -lh
% gdb ./crash_hugepage core
%
% echo 0x43 > /proc/self/coredump_filter
% ./crash_hugepage  50
% ./crash_hugepage  50  -p
% ls -lh
% gdb ./crash_hugepage core

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/mman.h>
#include <string.h>

#include "hugetlbfs.h"

int main(int argc, char** argv){
	char* p;
	int ch;
	int mmap_flags = MAP_SHARED;
	int fd;
	int nr_pages;

	while((ch = getopt(argc, argv, "p")) != -1) {
		switch (ch) {
		case 'p':
			mmap_flags &= ~MAP_SHARED;
			mmap_flags |= MAP_PRIVATE;
			break;
		default:
			/* nothing*/
			break;
		}
	}
	argc -= optind;
	argv += optind;

	if (argc == 0){
		printf("need # of pages\n");
		exit(1);
	}

	nr_pages = atoi(argv[0]);
	if (nr_pages < 2) {
		printf("nr_pages must >2\n");
		exit(1);
	}

	fd = hugetlbfs_unlinked_fd();
	p = mmap(NULL, nr_pages * gethugepagesize(),
		 PROT_READ|PROT_WRITE, mmap_flags, fd, 0);

	sleep(2);

	*(p + gethugepagesize()) = 1; /* COW */
	sleep(2);

	/* crash! */
	*(int*)0 = 1;

	return 0;
}

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Kawai Hidehiro <hidehiro.kawai.ez@hitachi.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: William Irwin <wli@holomorphy.com>
Cc: Adam Litke <agl@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 08:52:32 -07:00
Diego Calleja 22359f5745 ext4: Update Documentation/filesystems/ext4.txt
Since Ext4 is supposed to be stable in 2.6.28-rc, ext4's documentation
file should be updated.

[ More updates also added by Theodore Ts'o. ]

Signed-off-by: Diego Calleja <diegocg@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-10-17 09:15:14 -04:00
Ian Kent 4b22ff1341 autofs4: device node ioctl documentation
Add documentation for the miscellaneous device module of autofs4.

Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 11:21:39 -07:00
Bernhard Walle 22b8ab66de Document panic_on_unrecovered_nmi sysctl
This adds "panic_on_unrecovered_nmi" sysctl to
Documentation/filesystems/proc.txt. The text is mainly taken from
http://readlist.com/lists/vger.kernel.org/linux-kernel/43/217998.html.

Signed-off-by: Bernhard Walle <bwalle@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 11:21:32 -07:00
FD Cami 2223c65103 Remove Andrew Morton's http://www.zip.com.au/~akpm/
Remove Andrew Morton's http://www.zip.com.au/~akpm/ urls, update to new
ones when necessary, delete references otherwise.

There are still instances of that living in:
Documentation/zh_CN/HOWTO
Documentation/zh_CN/SubmittingPatches
Documentation/ko_KR/HOWTO
Documentation/ja_JP/SubmittingPatches

Signed-off-by: Francois Cami <francois.cami@free.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 11:21:32 -07:00
Shane McDonald 1c828320d2 doc: typo in Documentation/filesystems/nfsroot.txt
Add a missing word to the explanation of the purpose of the zdisk and
bzdisk make targets.

Signed-off-by: Shane McDonald <mcdonald.shane@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 11:21:31 -07:00
frans dd1c53a64a Fix Documentation/filesystems/ramfs-rootfs-initramfs.txt
First a file hello.c is created, then the file hello2.c is compiled.
Change this to hello.c

Signed-off-by: Frans Meulenbroeks <fransmeulenbroeks@gmail.com>
Signed-off-by: Rob Landley <rob@landley.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 11:21:30 -07:00
Mark Fasheh 696b55d768 ocfs2: Documentation update for user_xattr / nouser_xattr mount options
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-10-13 17:02:44 -07:00
Joel Becker 12462f1d9f ocfs2: Add the 'inode64' mount option.
Now that ocfs2 limits inode numbers to 32bits, add a mount option to
disable the limit.  This parallels XFS.  64bit systems can handle the
larger inode numbers.

[ Added description of inode64 mount option in ocfs2.txt. --Mark ]

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-10-13 16:57:08 -07:00
Linus Torvalds 20272c8994 Merge branch 'proc' of git://git.kernel.org/pub/scm/linux/kernel/git/adobriyan/proc
* 'proc' of git://git.kernel.org/pub/scm/linux/kernel/git/adobriyan/proc:
  proc: remove kernel.maps_protect
  proc: remove now unneeded ADDBUF macro
  [PATCH] proc: show personality via /proc/pid/personality
  [PATCH] signal, procfs: some lock_task_sighand() users do not need rcu_read_lock()
  proc: move PROC_PAGE_MONITOR to fs/proc/Kconfig
  proc: make grab_header() static
  proc: remove unused get_dma_list()
  proc: remove dummy vmcore_open()
  proc: proc_sys_root tweak
  proc: fix return value of proc_reg_open() in "too late" case

Fixed up trivial conflict in removed file arch/sparc/include/asm/dma_32.h
2008-10-13 10:04:04 -07:00
Hidehiro Kawai 5bf5683a33 ext4: add an option to control error handling on file data
If the journal doesn't abort when it gets an IO error in file data
blocks, the file data corruption will spread silently.  Because
most of applications and commands do buffered writes without fsync(),
they don't notice the IO error.  It's scary for mission critical
systems.  On the other hand, if the journal aborts whenever it gets
an IO error in file data blocks, the system will easily become
inoperable.  So this patch introduces a filesystem option to
determine whether it aborts the journal or just call printk() when
it gets an IO error in file data.

If you mount an ext4 fs with data_err=abort option, it aborts on file
data write error.  If you mount it with data_err=ignore, it doesn't
abort, just call printk().  data_err=ignore is the default.

Here is the corresponding patch of the ext3 version:
http://kerneltrap.org/mailarchive/linux-kernel/2008/9/9/3239374

Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2008-10-10 22:12:43 -04:00
Theodore Ts'o 03010a3350 ext4: Rename ext4dev to ext4
The ext4 filesystem is getting stable enough that it's time to drop
the "dev" prefix.  Also remove the requirement for the TEST_FILESYS
flag.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-10-10 20:02:48 -04:00
Alexey Dobriyan 3bbfe05967 proc: remove kernel.maps_protect
After commit 831830b5a2 aka
"restrict reading from /proc/<pid>/maps to those who share ->mm or can ptrace"
sysctl stopped being relevant because commit moved security checks from ->show
time to ->start time (mm_for_maps()).

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Kees Cook <kees.cook@canonical.com>
2008-10-10 04:24:51 +04:00
Mark Fasheh c4b929b85b vfs: vfs-level fiemap interface
Basic vfs-level fiemap infrastructure, which sets up a new ->fiemap
inode operation.

Userspace can get extent information on a file via fiemap ioctl. As input,
the fiemap ioctl takes a struct fiemap which includes an array of struct
fiemap_extent (fm_extents). Size of the extent array is passed as
fm_extent_count and number of extents returned will be written into
fm_mapped_extents. Offset and length fields on the fiemap structure
(fm_start, fm_length) describe a logical range which will be searched for
extents. All extents returned will at least partially contain this range.
The actual extent offsets and ranges returned will be unmodified from their
offset and range on-disk.

The fiemap ioctl returns '0' on success. On error, -1 is returned and errno
is set. If errno is equal to EBADR, then fm_flags will contain those flags
which were passed in which the kernel did not understand. On all other
errors, the contents of fm_extents is undefined.

As fiemap evolved, there have been many authors of the vfs patch. As far as
I can tell, the list includes:
Kalpak Shah <kalpak.shah@sun.com>
Andreas Dilger <adilger@sun.com>
Eric Sandeen <sandeen@redhat.com>
Mark Fasheh <mfasheh@suse.com>

Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Cc: linux-api@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
2008-10-08 19:44:18 -04:00
Theodore Ts'o 240799cdf2 ext4: Use readahead when reading an inode from the inode table
With modern hard drives, reading 64k takes roughly the same time as
reading a 4k block.  So request readahead for adjacent inode table
blocks to reduce the time it takes when iterating over directories
(especially when doing this in htree sort order) in a cold cache case.
With this patch, the time it takes to run "git status" on a kernel
tree after flushing the caches via "echo 3 > /proc/sys/vm/drop_caches"
is reduced by 21%.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-10-09 23:53:47 -04:00
Theodore Ts'o 37515facd0 ext4: Improve the documentation for ext4's /proc tunables
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Alex Tomas <bzzz@sun.com>
Cc: Andreas Dilger <adilger@sun.com>
2008-10-09 23:21:54 -04:00
Adrian Hunter 2953e73f1c UBIFS: add no_chk_data_crc mount option
UBIFS read performance can be improved by skipping the CRC
check when data nodes are read.  This option can be used if
the underlying media is considered to be highly reliable.
Note that CRCs are always checked for metadata.

Read speed on Arm platform with OneNAND goes from 19 MiB/s
to 27 MiB/s with data CRC checking disabled.

Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
2008-09-30 11:12:56 +03:00
Adrian Hunter 4793e7c5e1 UBIFS: add bulk-read facility
Some flash media are capable of reading sequentially at faster rates.
UBIFS bulk-read facility is designed to take advantage of that, by
reading in one go consecutive data nodes that are also located
consecutively in the same LEB.

Read speed on Arm platform with OneNAND goes from 17 MiB/s to
19 MiB/s.

Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
2008-09-30 11:12:56 +03:00
Hidehiro Kawai b261dfea48 coredump_filter: add description of bit 4
There is no description of bit 4 of coredump_filter in the
documentation.  This patch adds it.

Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-13 14:41:51 -07:00
Christoph Hellwig adaae7215e update Documentation/filesystems/Locking for 2.6.27 changes
In the 2.6.27 circle ->fasync lost the BKL, and the last remaining
->open variant that takes the BKL is also gone.  ->get_sb and ->kill_sb
didn't have BKL forever, so updated the entries while we're at that.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-09 11:51:15 -07:00
Nadia Derbey 61e55d0576 ipc: document the new auto_msgmni proc file
Update Documentation/filesystems/proc.txt: it describes the file
auto_msgmni intoduced to enable/disable msgmni automatic recomputing upon
memory add/remove (see thread http://lkml.org/lkml/2008/7/4/27).  Also
added a description for msgmni (this filex is only listed in
Documentation/sysctl/kernel.txt).

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-02 19:21:39 -07:00
Adrian Bunk 169ccbd44e NTFS: update homepage
Update the location of the NTFS homepage in several files.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-02 19:21:37 -07:00
Linus Torvalds ee26562772 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: Update documentation to remind users to update mke2fs.conf
  ext4: Fix small file fragmentation
  ext4: Initialize writeback_index to 0 when allocating a new inode
  ext4: make sure ext4_has_free_blocks returns 0 for ENOSPC
  ext4: journal credit fix for the delayed allocation's writepages() function
  ext4: Rework the ext4_da_writepages() function
  ext4: journal credits reservation fixes for DIO, fallocate
  ext4: journal credits reservation fixes for extent file writepage
  ext4: journal credits calulation cleanup and fix for non-extent writepage
  ext4: Fix bug where we return ENOSPC even though we have plenty of inodes
  ext4: don't try to resize if there are no reserved gdt blocks left
  ext4: Use ext4_discard_reservations instead of mballoc-specific call
  ext4: Fix ext4_dx_readdir hash collision handling
  ext4: Fix delalloc release block reservation for truncate
  ext4: Fix potential truncate BUG due to i_prealloc_list being non-empty
  ext4: Handle unwritten extent properly with delayed allocation
2008-08-22 08:37:07 -07:00
Sebastian Siewior 2e244d0836 Documentation: fix typo in ubifs.txt
Signed-off-by: Sebastian Siewior <bigeasy@linutronix.de>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-08-13 11:14:54 +03:00
Randy Dunlap 3794f3e812 docsrc: build Documentation/ sources
Currently source files in the Documentation/ sub-dir can easily bit-rot
since they are not generally buildable, either because they are hidden in
text files or because there are no Makefile rules for them.  This needs to
be fixed so that the source files remain usable and good examples of code
instead of bad examples.

Add the ability to build source files that are in the Documentation/ dir.
Add to Kconfig as "BUILD_DOCSRC" config symbol.

Use "CONFIG_BUILD_DOCSRC=1 make ..." to build objects from the
Documentation/ sources.  Or enable BUILD_DOCSRC in the *config system.
However, this symbol depends on HEADERS_CHECK since the header files need
to be installed (for userspace builds).

Built (using cross-tools) for x86-64, i386, alpha, ia64, sparc32,
sparc64, powerpc, sh, m68k, & mips.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-08-12 16:07:30 -07:00
Jan Kara 866c36637f quota: documentation for sending "below quota" messages via netlink and tiny doc update
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-08-12 16:07:27 -07:00
Joel Becker ecb3d28c7e [PATCH] configfs: Convenience macros for attribute definition.
Sysfs has the _ATTR() and _ATTR_RO() macros to make defining extended
form attributes easier.  configfs should have something similiar.

- _CONFIGFS_ATTR() and _CONFIGFS_ATTR_RO() are the counterparts to the
  sysfs macros.
- CONFIGFS_ATTR_STRUCT() creates the extended form attribute structure.
- CONFIGFS_ATTR_OPS() defines the show_attribute()/store_attribute()
  operations that call the show()/store() operations of the extended
  form configfs_attributes.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-07-31 16:21:13 -07:00
Theodore Ts'o 4537398d91 ext4: Update documentation to remind users to update mke2fs.conf
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-07-27 19:59:21 -04:00
Matt LaPlante d91958815d Documentation cleanup: trivial misspelling, punctuation, and grammar corrections.
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-26 12:00:06 -07:00
Bob Copeland a14e4b572b omfs: add filesystem documentation
These patches add the Optimized MPEG Filesystem, a proprietary filesystem used
by the embedded devices Rio Karma and ReplayTV, which are no longer
manufactured.  This filesystem module enables people to access files on these
devices.

This patch:

OMFS is a proprietary filesystem created for the ReplayTV and also used by the
Rio Karma.  It uses hash tables with unordered, unbounded lists in each bucket
for directories, extents for data blocks, 64-bit addressing for blocks, with
up to 8K blocks (only 2K of a given block is ever used for metadata, so the FS
still works with 4K pages).

Document the filesystem usage and structures.

Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-26 12:00:05 -07:00
Eduard - Gabriel Munteanu 20d8b67c06 relay: add buffer-only channels; useful for early logging
Allows one to create and use a channel with no associated files.  Files
can be initialized later.  This is useful in scenarios such as logging in
early code, before VFS is up.  Therefore, such channels can be created and
used as soon as kmem_cache_init() completed.

This is needed by kmemtrace to do tracing in early kernel code.

[kosaki.motohiro@jp.fujitsu.com: build fix]
Signed-off-by: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Cc: Tom Zanussi <tzanussi@gmail.com>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-26 12:00:04 -07:00
Joe Peterson 41003cde95 UTC timestamp option for FAT filesystems fix
Signed-off-by: Joe Peterson <joe@skyrush.com>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:34 -07:00
Eric Dumazet a47a126ad5 vmallocinfo: add NUMA information
Christoph recently added /proc/vmallocinfo file to get information about
vmalloc allocations.

This patch adds NUMA specific information, giving number of pages
allocated on each memory node.

This should help to check that vmalloc() is able to respect NUMA policies.

Example of output on a four nodes machine (one cpu per node)

1) network hash tables are evenly spreaded on four nodes (OK) (Same
   point for inodes and dentries hash tables)

2) iptables tables (x_tables) are correctly allocated on each cpu node
   (OK).

3) sys_swapon() allocates its memory from one node only.

4) each loaded module is using memory on one node.

Sysadmins could tune their setup to change points 3) and 4) if necessary.

grep "pages="  /proc/vmallocinfo
0xffffc20000000000-0xffffc20000201000 2101248 alloc_large_system_hash+0x204/0x2c0 pages=512 vmalloc N0=128 N1=128 N2=128 N3=128
0xffffc20000201000-0xffffc20000302000 1052672 alloc_large_system_hash+0x204/0x2c0 pages=256 vmalloc N0=64 N1=64 N2=64 N3=64
0xffffc2000031a000-0xffffc2000031d000   12288 alloc_large_system_hash+0x204/0x2c0 pages=2 vmalloc N1=1 N2=1
0xffffc2000031f000-0xffffc2000032b000   49152 cramfs_uncompress_init+0x2e/0x80 pages=11 vmalloc N0=3 N1=3 N2=2 N3=3
0xffffc2000033e000-0xffffc20000341000   12288 sys_swapon+0x640/0xac0 pages=2 vmalloc N0=2
0xffffc20000341000-0xffffc20000344000   12288 xt_alloc_table_info+0xfe/0x130 [x_tables] pages=2 vmalloc N0=2
0xffffc20000344000-0xffffc20000347000   12288 xt_alloc_table_info+0xfe/0x130 [x_tables] pages=2 vmalloc N1=2
0xffffc20000347000-0xffffc2000034a000   12288 xt_alloc_table_info+0xfe/0x130 [x_tables] pages=2 vmalloc N2=2
0xffffc2000034a000-0xffffc2000034d000   12288 xt_alloc_table_info+0xfe/0x130 [x_tables] pages=2 vmalloc N3=2
0xffffc20004381000-0xffffc20004402000  528384 alloc_large_system_hash+0x204/0x2c0 pages=128 vmalloc N0=32 N1=32 N2=32 N3=32
0xffffc20004402000-0xffffc20004803000 4198400 alloc_large_system_hash+0x204/0x2c0 pages=1024 vmalloc vpages N0=256 N1=256 N2=256 N3=256
0xffffc20004803000-0xffffc20004904000 1052672 alloc_large_system_hash+0x204/0x2c0 pages=256 vmalloc N0=64 N1=64 N2=64 N3=64
0xffffc20004904000-0xffffc20004bec000 3047424 sys_swapon+0x640/0xac0 pages=743 vmalloc vpages N0=743
0xffffffffa0000000-0xffffffffa000f000   61440 sys_init_module+0xc27/0x1d00 pages=14 vmalloc N1=14
0xffffffffa000f000-0xffffffffa0014000   20480 sys_init_module+0xc27/0x1d00 pages=4 vmalloc N0=4
0xffffffffa0014000-0xffffffffa0017000   12288 sys_init_module+0xc27/0x1d00 pages=2 vmalloc N0=2
0xffffffffa0017000-0xffffffffa0022000   45056 sys_init_module+0xc27/0x1d00 pages=10 vmalloc N1=10
0xffffffffa0022000-0xffffffffa0028000   24576 sys_init_module+0xc27/0x1d00 pages=5 vmalloc N3=5
0xffffffffa0028000-0xffffffffa0050000  163840 sys_init_module+0xc27/0x1d00 pages=39 vmalloc N1=39
0xffffffffa0050000-0xffffffffa0052000    8192 sys_init_module+0xc27/0x1d00 pages=1 vmalloc N1=1
0xffffffffa0052000-0xffffffffa0056000   16384 sys_init_module+0xc27/0x1d00 pages=3 vmalloc N1=3
0xffffffffa0056000-0xffffffffa0081000  176128 sys_init_module+0xc27/0x1d00 pages=42 vmalloc N3=42
0xffffffffa0081000-0xffffffffa00ae000  184320 sys_init_module+0xc27/0x1d00 pages=44 vmalloc N3=44
0xffffffffa00ae000-0xffffffffa00b1000   12288 sys_init_module+0xc27/0x1d00 pages=2 vmalloc N3=2
0xffffffffa00b1000-0xffffffffa00b9000   32768 sys_init_module+0xc27/0x1d00 pages=7 vmalloc N0=7
0xffffffffa00b9000-0xffffffffa00c4000   45056 sys_init_module+0xc27/0x1d00 pages=10 vmalloc N3=10
0xffffffffa00c6000-0xffffffffa00e0000  106496 sys_init_module+0xc27/0x1d00 pages=25 vmalloc N2=25
0xffffffffa00e0000-0xffffffffa00f1000   69632 sys_init_module+0xc27/0x1d00 pages=16 vmalloc N2=16
0xffffffffa00f1000-0xffffffffa00f4000   12288 sys_init_module+0xc27/0x1d00 pages=2 vmalloc N3=2
0xffffffffa00f4000-0xffffffffa00f7000   12288 sys_init_module+0xc27/0x1d00 pages=2 vmalloc N3=2

[akpm@linux-foundation.org: fix comment]
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:17 -07:00
Rik van Riel 28b2ee20c7 access_process_vm device memory infrastructure
In order to be able to debug things like the X server and programs using
the PPC Cell SPUs, the debugger needs to be able to access device memory
through ptrace and /proc/pid/mem.

This patch:

Add the generic_access_phys access function and put the hooks in place
to allow access_process_vm to access device or PPC Cell SPU memory.

[riel@redhat.com: Add documentation for the vm_ops->access function]
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Benjamin Herrensmidt <benh@kernel.crashing.org>
Cc: Dave Airlie <airlied@linux.ie>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:15 -07:00
Linus Torvalds 6eaaaac974 Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  remove CONFIG_KMOD from core kernel code
  remove CONFIG_KMOD from lib
  remove CONFIG_KMOD from sparc64
  rework try_then_request_module to do less in non-modular kernels
  remove mention of CONFIG_KMOD from documentation
  make CONFIG_KMOD invisible
  modules: Take a shortcut for checking if an address is in a module
  module: turn longs into ints for module sizes
  Shrink struct module: CONFIG_UNUSED_SYMBOLS ifdefs
  module: reorder struct module to save space on 64 bit builds
  module: generic each_symbol iterator function
  module: don't use stop_machine for waiting rmmod
2008-07-22 13:17:15 -07:00
Johannes Berg a81792f668 remove mention of CONFIG_KMOD from documentation
Also includes a few Kconfig files (xtensa, blackfin)

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: linux-doc@vger.kernel.org
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
2008-07-22 19:24:29 +10:00
Dan Williams e105b8bfc7 sysfs: add /sys/dev/{char,block} to lookup sysfs path by major:minor
Why?:
There are occasions where userspace would like to access sysfs
attributes for a device but it may not know how sysfs has named the
device or the path.  For example what is the sysfs path for
/dev/disk/by-id/ata-ST3160827AS_5MT004CK?  With this change a call to
stat(2) returns the major:minor then userspace can see that
/sys/dev/block/8:32 links to /sys/block/sdc.

What are the alternatives?:
1/ Add an ioctl to return the path: Doable, but sysfs is meant to reduce
   the need to proliferate ioctl interfaces into the kernel, so this
   seems counter productive.

2/ Use udev to create these symlinks: Also doable, but it adds a
   udev dependency to utilities that might be running in a limited
   environment like an initramfs.

3/ Do a full-tree search of sysfs.

[kay.sievers@vrfy.org: fix duplicate registrations]
[kay.sievers@vrfy.org: cleanup suggestions]

Cc: Neil Brown <neilb@suse.de>
Cc: Tejun Heo <htejun@gmail.com>
Acked-by: Kay Sievers <kay.sievers@vrfy.org>
Reviewed-by: SL Baur <steve@xemacs.org>
Acked-by: Kay Sievers <kay.sievers@vrfy.org>
Acked-by: Mark Lord <lkml@rtr.ca>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 21:54:40 -07:00
Linus Torvalds 14b395e35d Merge branch 'for-2.6.27' of git://linux-nfs.org/~bfields/linux
* 'for-2.6.27' of git://linux-nfs.org/~bfields/linux: (51 commits)
  nfsd: nfs4xdr.c do-while is not a compound statement
  nfsd: Use C99 initializers in fs/nfsd/nfs4xdr.c
  lockd: Pass "struct sockaddr *" to new failover-by-IP function
  lockd: get host reference in nlmsvc_create_block() instead of callers
  lockd: minor svclock.c style fixes
  lockd: eliminate duplicate nlmsvc_lookup_host call from nlmsvc_lock
  lockd: eliminate duplicate nlmsvc_lookup_host call from nlmsvc_testlock
  lockd: nlm_release_host() checks for NULL, caller needn't
  file lock: reorder struct file_lock to save space on 64 bit builds
  nfsd: take file and mnt write in nfs4_upgrade_open
  nfsd: document open share bit tracking
  nfsd: tabulate nfs4 xdr encoding functions
  nfsd: dprint operation names
  svcrdma: Change WR context get/put to use the kmem cache
  svcrdma: Create a kmem cache for the WR contexts
  svcrdma: Add flush_scheduled_work to module exit function
  svcrdma: Limit ORD based on client's advertised IRD
  svcrdma: Remove unused wait q from svcrdma_xprt structure
  svcrdma: Remove unneeded spin locks from __svc_rdma_free
  svcrdma: Add dma map count and WARN_ON
  ...
2008-07-20 21:21:46 -07:00
Joel Becker a6795e9ebb configfs: Allow ->make_item() and ->make_group() to return detailed errors.
The configfs operations ->make_item() and ->make_group() currently
return a new item/group.  A return of NULL signifies an error.  Because
of this, -ENOMEM is the only return code bubbled up the stack.

Multiple folks have requested the ability to return specific error codes
when these operations fail.  This patch adds that ability by changing the
->make_item/group() ops to return ERR_PTR() values.  These errors are
bubbled up appropriately.  NULL returns are changed to -ENOMEM for
compatibility.

Also updated are the in-kernel users of configfs.

This is a rework of reverted commit 11c3b79218.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
2008-07-17 15:21:29 -07:00
Joel Becker f89ab8619e Revert "configfs: Allow ->make_item() and ->make_group() to return detailed errors."
This reverts commit 11c3b79218.  The code
will move to PTR_ERR().

Signed-off-by: Joel Becker <joel.becker@oracle.com>
2008-07-17 14:53:48 -07:00
Linus Torvalds 5b664cb235 Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2:
  [PATCH] ocfs2: fix oops in mmap_truncate testing
  configfs: call drop_link() to cleanup after create_link() failure
  configfs: Allow ->make_item() and ->make_group() to return detailed errors.
  configfs: Fix failing mkdir() making racing rmdir() fail
  configfs: Fix deadlock with racing rmdir() and rename()
  configfs: Make configfs_new_dirent() return error code instead of NULL
  configfs: Protect configfs_dirent s_links list mutations
  configfs: Introduce configfs_dirent_lock
  ocfs2: Don't snprintf() without a format.
  ocfs2: Fix CONFIG_OCFS2_DEBUG_FS #ifdefs
  ocfs2/net: Silence build warnings on sparc64
  ocfs2: Handle error during journal load
  ocfs2: Silence an error message in ocfs2_file_aio_read()
  ocfs2: use simple_read_from_buffer()
  ocfs2: fix printk format warnings with OCFS2_FS_STATS=n
  [PATCH 2/2] ocfs2: Instrument fs cluster locks
  [PATCH 1/2] ocfs2: Add CONFIG_OCFS2_FS_STATS config option
2008-07-17 10:55:51 -07:00
Linus Torvalds 9c1be0c471 Merge branch 'for_linus' of git://git.infradead.org/~dedekind/ubifs-2.6
* 'for_linus' of git://git.infradead.org/~dedekind/ubifs-2.6:
  UBIFS: include to compilation
  UBIFS: add new flash file system
  UBIFS: add brief documentation
  MAINTAINERS: add UBIFS section
  do_mounts: allow UBI root device name
  VFS: export sync_sb_inodes
  VFS: move inode_lock into sync_sb_inodes
2008-07-16 15:02:57 -07:00
Linus Torvalds 61d97f4fcf Merge branch 'genirq' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'genirq' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  genirq: remove extraneous checks in manage.c
  genirq: Expose default irq affinity mask (take 3)
2008-07-15 10:39:22 -07:00
Linus Torvalds 38c46578ff Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw
* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw:
  [GFS2] Fix GFS2's use of do_div() in its quota calculations
  [GFS2] Remove unused declaration
  [GFS2] Remove support for unused and pointless flag
  [GFS2] Replace rgrp "recent list" with mru list
  [GFS2] Allow local DF locks when holding a cached EX glock
  [GFS2] Fix delayed demote race
  [GFS2] don't call permission()
  [GFS2] Fix module building
  [GFS2] Glock documentation
  [GFS2] Remove all_list from lock_dlm
  [GFS2] Remove obsolete conversion deadlock avoidance code
  [GFS2] Remove remote lock dropping code
  [GFS2] kernel panic mounting volume
  [GFS2] Revise readpage locking
  [GFS2] Fix ordering of args for list_add
  [GFS2] trivial sparse lock annotations
  [GFS2] No lock_nolock
  [GFS2] Fix ordering bug in lock_dlm
  [GFS2] Clean up the glock core
2008-07-15 10:38:46 -07:00
Artem Bityutskiy e56a99d5a4 UBIFS: add brief documentation
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
2008-07-15 09:22:12 +03:00
Joel Becker 11c3b79218 configfs: Allow ->make_item() and ->make_group() to return detailed errors.
The configfs operations ->make_item() and ->make_group() currently
return a new item/group.  A return of NULL signifies an error.  Because
of this, -ENOMEM is the only return code bubbled up the stack.

Multiple folks have requested the ability to return specific error codes
when these operations fail.  This patch adds that ability by changing the
->make_item/group() ops to return an int.

Also updated are the in-kernel users of configfs.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
2008-07-14 13:57:16 -07:00
Mingming Cao 49f1487b2e ext4: Documention update for new ordered mode and delayed allocation
Adding some documentations for delayed allocation and new ordered mode.

Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-07-11 19:27:31 -04:00
Jose R. Santos 93e3270c87 ext4: Documentation updates.
Some of the information in Documentation/filesystems/ext4.txt is out
of date and in need of an update.

Signed-off-by: Jose R. Santos <jrs@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-07-11 19:27:31 -04:00
J. Bruce Fields e86322f611 Merge branch 'for-bfields' of git://linux-nfs.org/~tomtucker/xprt-switch-2.6 into for-2.6.27 2008-07-03 16:24:06 -04:00
J. Bruce Fields 3cd2cfeae1 nfs: rewrap NFS/RDMA documentation to 80 lines
Wrap long lines.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-06-30 15:24:43 -04:00
James Lentini 007de8b4fd update NFS/RDMA documentation
Update the NFS/RDMA documentation to clarify how to run mount.nfs.

Signed-off-by: James Lentini <jlentini@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-06-30 15:24:43 -04:00
Steven Whitehouse 9f1585cb03 [GFS2] Glock documentation
This patch adds a file describing the internals of GFS2's glock
abstraction.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2008-06-27 09:39:53 +01:00
Jesse Barnes 883eed1b3e Merge branch 'pci-for-jesse' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-tip into for-linus 2008-06-12 13:51:05 -07:00
venkatesh.pallipadi@intel.com 45aec1ae72 x86: PAT export resource_wc in pci sysfs
For the ranges with IORESOURCE_PREFETCH, export a new resource_wc interface in
pci /sysfs along with resource (which is uncached).

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-06-12 10:12:42 +02:00
Max Krasnyansky 1840475676 genirq: Expose default irq affinity mask (take 3)
Current IRQ affinity interface does not provide a way to set affinity
for the IRQs that will be allocated/activated in the future.
This patch creates /proc/irq/default_smp_affinity that lets users set
default affinity mask for the newly allocated IRQs. Changing the default
does not affect affinity masks for the currently active IRQs, they
have to be changed explicitly.

Updated based on Paul J's comments and added some more documentation.

Signed-off-by: Max Krasnyansky <maxk@qualcomm.com>
Cc: pj@sgi.com
Cc: a.p.zijlstra@chello.nl
Cc: tglx@linutronix.de
Cc: rdunlap@xenotime.net
Cc: mingo@elte.hu
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-06-05 15:18:30 +02:00
Eric Sandeen 571640cad3 ext4: enable barriers by default
I can't think of any valid reason for ext4 to not use barriers when
they are available;  I believe this is necessary for filesystem
integrity in the face of a volatile write cache on storage.

An administrator who trusts that the cache is sufficiently battery-
backed (and power supplies are sufficiently redundant, etc...)
can always turn it back off again.

SuSE has carried such a patch for ext3 for quite some time now.

Also document the mount option while we're at it.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-05-26 12:29:46 -04:00
Christoph Hellwig 33dcdac2df [PATCH] kill ->put_inode
And with that last patch to affs killing the last put_inode instance we
can finally, after many years of transition kill this racy and awkward
interface.

(It's kinda funny that even the description in
Documentation/filesystems/vfs.txt was entirely wrong..)

Also remove a very misleading comment above the defintion of
struct super_operations.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-05-06 13:45:34 -04:00
Miklos Szeredi b88473f73e mm: document missing fields for /proc/meminfo
A few fields in /proc/meminfo were not documented.  Fix.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:50 -07:00
OGAWA Hirofumi 1ae43f826b fat: Add allow_utime option
Normally utime(2) checks current process is owner of the file, or it
has CAP_FOWNER capability.  But FAT filesystem doesn't have uid/gid as
on disk info, so normal check is too unflexible.

With this option you can relax it.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:47 -07:00
David Rientjes 65d66fc02e mempolicy: update NUMA memory policy documentation
Updates Documentation/vm/numa_memory_policy.txt and
Documentation/filesystems/tmpfs.txt to describe optional mempolicy mode flags.

Cc: Christoph Lameter <clameter@sgi.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:19 -07:00
Nick Piggin 3c18ddd160 mm: remove nopage
Nothing in the tree uses nopage any more.  Remove support for it in the
core mm code and documentation (and a few stray references to it in
comments).

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:18 -07:00
Linus Torvalds cf2ec150fc Merge branch 'for-linus' of git://linux-nfs.org/~bfields/linux
* 'for-linus' of git://linux-nfs.org/~bfields/linux:
  nfsd: don't allow setting ctime over v4
  Update to NFS/RDMA documentation
  locks: don't call ->copy_lock methods on return of conflicting locks
  lockd: unlock lockd locks held for a certain filesystem
  lockd: unlock lockd locks associated with a given server ip
  leases: remove unneeded variable from fcntl_setlease().
  leases: move lock allocation earlier in generic_setlease()
  leases: when unlocking, skip locking-related steps
  leases: fix a return-value mixup
2008-04-25 11:45:40 -07:00
Jonathan Corbet 9f4def9ae4 Document seq_path_root()
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2008-04-25 11:56:37 -06:00
James Lentini c272cca625 Update to NFS/RDMA documentation
Update to the NFS/RDMA documentation to clarify how to configure the
exports file.

Signed-off-by: James Lentini <jlentini@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-04-25 13:00:11 -04:00
Jonathan Corbet 22c36d18c6 Document SEQ_SKIP
2.6.26 adds a SEQ_SKIP return value for the seq_file show() function;
update the documentation to match.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2008-04-24 15:57:32 -06:00
James Lentini a3fa73bd0e Documentation: NFS/RDMA instructions for 2.6.25-rc1
Add some instructions for using the new NFS/RDMA features.

Signed-off-by: James Lentini <jlentini@netapp.com>
Cc: Roland Dreier <rdreier@cisco.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-04-23 16:13:40 -04:00
Miklos Szeredi 97e7e0f71d [patch 7/7] vfs: mountinfo: show dominating group id
Show peer group ID of nearest dominating group that has intersection
with the mount's namespace.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-23 00:05:09 -04:00
Ram Pai 2d4d4864ac [patch 6/7] vfs: mountinfo: add /proc/<pid>/mountinfo
[mszeredi@suse.cz] rewrite and split big patch into managable chunks

/proc/mounts in its current form lacks important information:

 - propagation state
 - root of mount for bind mounts
 - the st_dev value used within the filesystem
 - identifier for each mount and it's parent

It also suffers from the following problems:

 - not easily extendable
 - ambiguity of mountpoints within a chrooted environment
 - doesn't distinguish between filesystem dependent and independent options
 - doesn't distinguish between per mount and per super block options

This patch introduces /proc/<pid>/mountinfo which attempts to address
all these deficiencies.

Code shared between /proc/<pid>/mounts and /proc/<pid>/mountinfo is
extracted into separate functions.

Thanks to Al Viro for the help in getting the design right.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-23 00:05:03 -04:00
Dan Williams 2424b5dd06 sysfs: refill attribute buffer when reading from offset 0
Requiring userspace to close and re-open sysfs attributes has been the
policy since before 2.6.12.  It allows userspace to get a consistent
snapshot of kernel state and consume it with incremental reads and seeks.

Now, if the file position is zero the kernel assumes userspace wants to see
the new value.  The application for this change is to allow a userspace
RAID metadata handler to check the state of an array without causing any
memory allocations.  Thus not causing writeback to a raid array that might
be blocked waiting for userspace to take action.

Cc: Neil Brown <neilb@suse.de>
Acked-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-19 19:10:29 -07:00
Josef Sipek f6e9f28865 [XFS] Update XFS documentation for noikeep/ikeep.
Mention how DMAPI affects default for noikeep.
Slightly modified since Josef's patch was based on
an old xfs.txt prior to Dave's (dgc) checkin which
missed going to oss.

Signed-off-by: Josef Sipek <jeffpc@josefsipek.net>
Signed-off-by: Tim Shimmin <tes@sgi.com>
2008-04-18 12:18:42 +10:00
David Chinner 033bfb1a65 [XFS] Update XFS Documentation for ikeep and ihashsize
Update xfs docs for:
* In memory inode hashes has been removed.
* noikeep is now the default.

SGI-PV: 969561
SGI-Modid: 2.6.x-xfs-melb:linux:29481b

Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Tim Shimmin <tes@sgi.com>
2008-04-18 12:18:25 +10:00
Dmitri Vorobiev b82d4043b3 Fix typos in Documentation/filesystems/seq_file.txt
A couple of typos crept into the newly added document about the seq_file
interface.  This patch corrects those typos and simultaneously deletes
unnecessary trailing spaces.

Signed-off-by: Dmitri Vorobiev <dmitri.vorobiev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-15 19:35:40 -07:00
J. Bruce Fields 8bcd1cc293 Documentation: move rpc-cache.txt to filesystems/
This file is nfs-related.  (Maybe Documentation/filesystems/ would
benefit from a separate nfs/ directory at some point.)

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2008-04-11 13:20:52 -06:00
J. Bruce Fields 6ded55da6b Documentation: move nfsroot.txt to filesystems/
Documentation/ is a little large, and filesystems/ seems an obvious
place for this file.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2008-04-11 13:18:01 -06:00
Jan Engelhardt f3271f6564 Fixes to the seq_file document
On Friday 2008-03-28 19:20, Jonathan Corbet wrote:
>commit 9756ccfda31b4c4544aa010aacf71b6672d668e8
>Date:   Fri Mar 28 11:19:56 2008 -0600
>
>    Add the seq_file documentation

patch on top:

  - add const qualifiers
  - remove void* casts
  - use proper specifier (%Ld is not valid)

Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
2008-03-30 11:05:04 -06:00
Jonathan Corbet ded4926aa2 Add the seq_file documentation
This is an updated version of the document describing the seq_file
interface.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2008-03-30 11:05:04 -06:00
Randy Dunlap a09a20b526 laptops: move laptop-mode.txt to Documentation/laptops/
Move laptop-mode.txt into the laptops/ sub-directory to consolidate
laptop doc files there.

Update references to the file's location.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2008-03-12 02:37:21 -04:00
Miklos Szeredi f84e3f521e mount options: add documentation
This series addresses the problem of showing mount options in
/proc/mounts.

Several filesystems which use mount options, have not implemented a
.show_options superblock operation.  Several others have implemented
this callback, but have not kept it fully up to date with the parsed
options.

Q: Why do we need correct option showing in /proc/mounts?
A: We want /proc/mounts to fully replace /etc/mtab.  The reasons for
   this are:
    - unprivileged mounters won't be able to update /etc/mtab
    - /etc/mtab doesn't work with private mount namespaces
    - /etc/mtab can become out-of-sync with reality

Q: Can't this be done, so that filesystems need not bother with
   implementing a .show_mounts callback, and keeping it up to date?
A: Only in some cases.  Certain filesystems allow modification of a
   subset of options in their remount_fs method.  It is not possible
   to take this into account without knowing exactly how the
   filesystem handles options.

For the simple case (no remount or remount resets all options) the
patchset introduces two helpers:

  generic_show_options()
  save_mount_options()

These can also be used to emulate the old /etc/mtab behavior, until
proper support is added.  Even if this is not 100% correct, it's still
better than showing no options at all.

The following patches fix up most in-tree filesystems, some have been
compile tested only, some have been reviewed and acked by the
maintainer.

Table displaying status of all in-kernel filesystems:
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
legend:

  none - fs has options, but doesn't define ->show_options()
  some - fs defines ->show_options(), but some only options are shown
  good - fs shows all options
  noopt - fs does not have options
  patch - a patch will be posted
  merged - a patch has been merged by subsystem maintainer

9p          good
adfs        patch
affs        patch
afs         patch
autofs      patch
autofs4     patch
befs        patch
bfs         noopt
cifs        some
coda        noopt
configfs    noopt
cramfs      noopt
debugfs     noopt
devpts      patch
ecryptfs    good
efs         noopt
ext2        patch
ext3        good
ext4        merged
fat         patch
freevxfs    noopt
fuse        patch
fusectl	    noopt
gfs2        good
gfs2meta    noopt
hfs         good
hfsplus     good
hostfs      patch
hpfs        patch
hppfs       noopt
hugetlbfs   patch
isofs       patch
jffs2       noopt
jfs         merged
minix       noopt
msdos       ->fat
ncpfs       patch
nfs         some
nfsd        noopt
ntfs        good
ocfs2       good
ocfs2/dlmfs noopt
openpromfs  noopt
proc        noopt
qnx4        noopt
ramfs       noopt
reiserfs    patch
romfs       noopt
smbfs       good
sysfs       noopt
sysv        noopt
udf         patch
ufs         good
vfat        ->fat
xfs         good

mm/shmem.c                                    patch
drivers/oprofile/oprofilefs.c                 noopt
drivers/infiniband/hw/ipath/ipath_fs.c        noopt
drivers/misc/ibmasm/ibmasmfs.c                noopt
drivers/usb/core (usbfs)                      merged
drivers/usb/gadget (gadgetfs)                 noopt
drivers/isdn/capi/capifs.c                    patch
kernel/cpuset.c                               noopt
fs/binfmt_misc.c                              noopt
net/sunrpc/rpc_pipe.c                         noopt
arch/powerpc/platforms/cell/spufs             patch
arch/s390/hypfs                               good
ipc/mqueue.c                                  noopt
security (securityfs)                         noopt
security/selinux/selinuxfs.c                  noopt
kernel/cgroup.c                               good
security/smack/smackfs.c                      noopt

in -mm:

reiser4     some
unionfs     good
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

This patch:

Document the rules for handling mount options in the .show_options
super operation.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:39 -08:00
Jan Kara 9b7880e7bb isofs: implement dmode option
Implement dmode option for iso9660 filesystem to allow setting of access
rights for directories on the filesystem.

Signed-off-by: Jan Kara <jack@suse.cz>
Cc: "Ilya N. Golubev" <gin@mo.msk.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:38 -08:00
David Howells 12debc4248 iget: remove iget() and the read_inode() super op as being obsolete
Remove the old iget() call and the read_inode() superblock operation it uses
as these are really obsolete, and the use of read_inode() does not produce
proper error handling (no distinction between ENOMEM and EIO when marking an
inode bad).

Furthermore, this removes the temptation to use iget() to find an inode by
number in a filesystem from code outside that filesystem.

iget_locked() should be used instead.  A new function is added in an earlier
patch (iget_failed) that is to be called to mark an inode as bad, unlock it
and release it should the get routine fail.  Mark iget() and read_inode() as
being obsolete and remove references to them from the documentation.

Typically a filesystem will be modified such that the read_inode function
becomes an internal iget function, for example the following:

	void thingyfs_read_inode(struct inode *inode)
	{
		...
	}

would be changed into something like:

	struct inode *thingyfs_iget(struct super_block *sp, unsigned long ino)
	{
		struct inode *inode;
		int ret;

		inode = iget_locked(sb, ino);
		if (!inode)
			return ERR_PTR(-ENOMEM);
		if (!(inode->i_state & I_NEW))
			return inode;

		...
		unlock_new_inode(inode);
		return inode;
	error:
		iget_failed(inode);
		return ERR_PTR(ret);
	}

and then thingyfs_iget() would be called rather than iget(), for example:

	ret = -EINVAL;
	inode = iget(sb, ino);
	if (!inode || is_bad_inode(inode))
		goto error;

becomes:

	inode = thingyfs_iget(sb, ino);
	if (IS_ERR(inode)) {
		ret = PTR_ERR(inode);
		goto error;
	}

Note that is_bad_inode() does not need to be called.  The error returned by
thingyfs_iget() should render it unnecessary.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-07 08:42:29 -08:00
David Howells b46980feed iget: introduce a function to register iget failure
Introduce a function to register failure in an inode construction path.  This
includes marking the inode under construction as bad, unlocking it and
releasing it.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-07 08:42:26 -08:00
J. Bruce Fields d3cf91d0e2 Documentation: move sharedsubtrees.txt to filesystems/
This documentation is also vfs-related.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-07 08:42:17 -08:00
J. Bruce Fields e9b1a4d160 Documentation: move dnotify.txt to filesystems/
I'm inclined to think dnotify belongs in filesystems/.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-07 08:42:17 -08:00
Eric Dumazet 9cfe015aa4 get rid of NR_OPEN and introduce a sysctl_nr_open
NR_OPEN (historically set to 1024*1024) actually forbids processes to open
more than 1024*1024 handles.

Unfortunatly some production servers hit the not so 'ridiculously high
value' of 1024*1024 file descriptors per process.

Changing NR_OPEN is not considered safe because of vmalloc space potential
exhaust.

This patch introduces a new sysctl (/proc/sys/fs/nr_open) wich defaults to
1024*1024, so that admins can decide to change this limit if their workload
needs it.

[akpm@linux-foundation.org: export it for sparc64]
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06 10:41:06 -08:00
Yasunori Goto 7786fa9ac5 Document lowmem_reserve_ratio
Though the lower_zone_protection was changed to lowmem_reserve_ratio, the
document has been not changed.  The lowmem_reserve_ratio seems quite hard
to estimate, but there is no guidance.  This patch is to change document
for it.

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Andrea Arcangeli <andrea@cpushare.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 09:44:19 -08:00
Bron Gondwana 195cf453d2 mm/page-writeback: highmem_is_dirtyable option
Add vm.highmem_is_dirtyable toggle

A 32 bit machine with HIGHMEM64 enabled running DCC has an MMAPed file of
approximately 2Gb size which contains a hash format that is written
randomly by the dbclean process.  On 2.6.16 this process took a few
minutes.  With lowmem only accounting of dirty ratios, this takes about 12
hours of 100% disk IO, all random writes.

Include a toggle in /proc/sys/vm/highmem_is_dirtyable which can be set to 1 to
add the highmem back to the total available memory count.

[akpm@linux-foundation.org: Fix the CONFIG_DETECT_SOFTLOCKUP=y build]
Signed-off-by: Bron Gondwana <brong@fastmail.fm>
Cc: Ethan Solomita <solo@google.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: WU Fengguang <wfg@mail.ustc.edu.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 09:44:18 -08:00
Oliver Pinter 3eb43f689c Documentation/filesystems/porting fixes
typo fix and whitespace cleanup

Signed-off-by: Oliver Pinter <oliver.pntr@gmail.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
2008-02-03 17:59:17 +02:00
Randy Dunlap 254012fd51 doc: use correct debugfs mountpoint
Use the normal, expected mountpoint in the relay(fs) example
for debugfs.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
2008-02-03 16:30:51 +02:00
Leonardo Chiquitto 2e01e00e76 Documentation: missing proc/$PID/stat field
There's a missing field in the /proc/$PID/stat output documented in
Documentation/filesystems/proc.txt.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
2008-02-03 16:17:16 +02:00
Masatake YAMATO 48cc7ec93f correct missing a double quote in configfs.txt
Signed-off-by: Masatake YAMATO <jet@gyve.org>
Acked-by: Joel Becker <Joel.Becker@oracle.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
2008-02-03 16:10:08 +02:00
Denis Cheng 33b1302545 Documentation: fix type error
Signed-off-by: Denis Cheng <crquan@gmail.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
2008-02-03 14:50:11 +02:00
Eric Paris de6bbd1d30 [AUDIT] break large execve argument logging into smaller messages
execve arguments can be quite large.  There is no limit on the number of
arguments and a 4G limit on the size of an argument.

this patch prints those aruguments in bite sized pieces.  a userspace size
limitation of 8k was discovered so this keeps messages around 7.5k

single arguments larger than 7.5k in length are split into multiple records
and can be identified as aX[Y]=

Signed-off-by: Eric Paris <eparis@redhat.com>
2008-02-01 14:23:55 -05:00
Eric Dumazet 29e75252da [IPV4] route cache: Introduce rt_genid for smooth cache invalidation
Current ip route cache implementation is not suited to large caches.

We can consume a lot of CPU when cache must be invalidated, since we
currently need to evict all cache entries, and this eviction is
sometimes asynchronous. min_delay & max_delay can somewhat control this
asynchronism behavior, but whole thing is a kludge, regularly triggering
infamous soft lockup messages. When entries are still in use, this also
consumes a lot of ram, filling dst_garbage.list.

A better scheme is to use a generation identifier on each entry,
so that cache invalidation can be performed by changing the table
identifier, without having to scan all entries.
No more delayed flushing, no more stalling when secret_interval expires.

Invalidated entries will then be freed at GC time (controled by
ip_rt_gc_timeout or stress), or when an invalidated entry is found
in a chain when an insert is done.
Thus we keep a normal equilibrium.

This patch :
- renames rt_hash_rnd to rt_genid (and makes it an atomic_t)
- Adds a new rt_genid field to 'struct rtable' (filling a hole on 64bit)
- Checks entry->rt_genid at appropriate places :
2008-01-31 19:28:27 -08:00
Alex Tomas c9de560ded ext4: Add multi block allocator for ext4
Signed-off-by: Alex Tomas <alex@clusterfs.com>
Signed-off-by: Andreas Dilger <adilger@clusterfs.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-01-29 00:19:52 -05:00
Girish Shilamkar 818d276ceb ext4: Add the journal checksum feature
The journal checksum feature adds two new flags i.e
JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT and JBD2_FEATURE_COMPAT_CHECKSUM.

JBD2_FEATURE_CHECKSUM flag indicates that the commit block contains the
checksum for the blocks described by the descriptor blocks.
Due to checksums, writing of the commit record no longer needs to be
synchronous. Now commit record can be sent to disk without waiting for
descriptor blocks to be written to disk. This behavior is controlled
using JBD2_FEATURE_ASYNC_COMMIT flag. Older kernels/e2fsck should not be
able to recover the journal with _ASYNC_COMMIT hence it is made
incompat.
The commit header has been extended to hold the checksum along with the
type of the checksum.

For recovery in pass scan checksums are verified to ensure the sanity
and completeness(in case of _ASYNC_COMMIT) of every transaction.

Signed-off-by: Andreas Dilger <adilger@clusterfs.com>
Signed-off-by: Girish Shilamkar <girish@clusterfs.com>
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
2008-01-28 23:58:27 -05:00
Mark Fasheh 53fc622b9e [PATCH 2/2] ocfs2: cluster aware flock()
Hook up ocfs2_flock(), using the new flock lock type in dlmglue.c. A new
mount option, "localflocks" is added so that users can revert to old
functionality as need be.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
2008-01-25 15:05:43 -08:00
Sunil Mushran 2fbe8d1ebe ocfs2: Local alloc window size changeable via mount option
Local alloc is a performance optimization in ocfs2 in which a node
takes a window of bits from the global bitmap and then uses that for
all small local allocations. This window size is fixed to 8MB currently.
This patch allows users to specify the window size in MB including
disabling it by passing in 0. If the number specified is too large,
the fs will use the default value of 8MB.

mount -o localalloc=X /dev/sdX /mntpoint

Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
2008-01-25 15:05:43 -08:00
Mark Fasheh d147b3d630 ocfs2: Support commit= mount option
Mostly taken from ext3. This allows the user to set the jbd commit interval,
in seconds. The default of 5 seconds stays the same, but now users can
easily increase the commit interval. Typically, this would be increased in
order to benefit performance at the expense of data-safety.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
2008-01-25 15:05:42 -08:00
Mark Fasheh 1252c434e3 ocfs2: Documentation update
Remove 'readpages' from the list in ocfs2.txt. Instead of having two
identical lists, I just removed the list in the OCFS2 section of fs/Kconfig
and added a pointer to Documentation/filesystems/ocfs2.txt.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
2008-01-25 14:48:42 -08:00
Eric Van Hensbergen b530cc7940 9p: add virtio transport
This adds a transport to 9p for communicating between guests and a host
using a virtio based transport.

Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2007-10-23 13:47:31 -05:00
Christoph Hellwig e38f981758 exportfs: update documentation
Update documentation to the current state of affairs.  Remove duplicated
method descruptions in exportfs.h and point to Documentation/filesystems/
Exporting instead.  Add a little file header comment in expfs.c describing
what's going on and mentioning Neils and my copyright [1].

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Neil Brown <neilb@suse.de>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: <linux-ext4@vger.kernel.org>
Cc: Dave Kleikamp <shaggy@austin.ibm.com>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: David Chinner <dgc@sgi.com>
Cc: Timothy Shimmin <tes@sgi.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Chris Mason <mason@suse.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: "Vladimir V. Saveliev" <vs@namesys.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-22 08:13:21 -07:00
Leonardo Chiquitto b68f2c3a98 proc.txt: Add /proc/stat field
This patch updates the "cat /proc/stat" output found
in Documentation/filesystems/proc.txt.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
2007-10-20 03:03:38 +02:00
Shaun Zinck f8c34f9816 docs/sysfs: add missing word to sysfs attribute explanation
Add the obvious missing word.

Signed-off-by: Shaun Zinck <shaun.zinck@gmail.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
2007-10-20 02:39:43 +02:00
Shaun Zinck 7356337bd2 documentation/ext3: grammar fixes
Fix some grammar in the explanation of the Journal Block Device layer.

Signed-off-by: Shaun Zinck <shaun.zinck@gmail.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
2007-10-20 02:38:36 +02:00
Shaun Zinck bc5b1d55cc Documentation/filesystems/vfs.txt: typo fix
Signed-off-by: Shaun Zinck <shaun.zinck@gmail.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
2007-10-20 02:35:36 +02:00
Eric Dumazet 94547426db Documentation/filesystems/files.txt: remove rcuref_inc_lf() reverences
rcuref_inc_lf() is not used anymore. Replace it by atomic_inc_not_zero()

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
2007-10-20 01:47:49 +02:00
Matt LaPlante 01dd2fbf0d typo fixes
Most of these fixes were already submitted for old kernel versions, and were
approved, but for some reason they never made it into the releases.

Because this is a consolidation of a couple old missed patches, it touches both
Kconfigs and documentation texts.

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
2007-10-20 01:34:40 +02:00
Robert P. J. Day 3a4fa0a25d Fix misspellings of "system", "controller", "interrupt" and "necessary".
Fix the various misspellings of "system", controller", "interrupt" and
"[un]necessary".

Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
2007-10-19 23:10:43 +02:00
Linus Torvalds 9d8190f87b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs:
  9p: remove sysctl
  9p: fix bad kconfig cross-dependency
  9p: soften invalidation in loose_mode
  9p: attach-per-user
  9p: rename uid and gid parameters
  9p: define session flags
  9p: Make transports dynamic
2007-10-17 15:05:58 -07:00
Latchesar Ionkov ba17674fe0 9p: attach-per-user
The 9P2000 protocol requires the authentication and permission checks to be
done in the file server. For that reason every user that accesses the file
server tree has to authenticate and attach to the server separately.
Multiple users can share the same connection to the server.

Currently v9fs does a single attach and executes all I/O operations as a
single user. This makes using v9fs in multiuser environment unsafe as it
depends on the client doing the permission checking.

This patch improves the 9P2000 support by allowing every user to attach
separately. The patch defines three modes of access (new mount option
'access'):

- attach-per-user (access=user) (default mode for 9P2000.u)
 If a user tries to access a file served by v9fs for the first time, v9fs
 sends an attach command to the server (Tattach) specifying the user. If
 the attach succeeds, the user can access the v9fs tree.
 As there is no uname->uid (string->integer) mapping yet, this mode works
 only with the 9P2000.u dialect.

- allow only one user to access the tree (access=<uid>)
 Only the user with uid can access the v9fs tree. Other users that attempt
 to access it will get EPERM error.

- do all operations as a single user (access=any) (default for 9P2000)
 V9fs does a single attach and all operations are done as a single user.
 If this mode is selected, the v9fs behavior is identical with the current
 one.

Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2007-10-17 14:31:07 -05:00
Latchesar Ionkov bd32b82df9 9p: rename uid and gid parameters
Change the names of 'uid' and 'gid' parameters to the more appropriate
'dfltuid' and 'dfltgid'.  This also sets the default uid/gid to -2
(aka nfsnobody)

Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2007-10-17 14:31:07 -05:00
Eric Van Hensbergen a80d923e13 9p: Make transports dynamic
This patch abstracts out the interfaces to underlying transports so that
new transports can be added as modules.  This should also allow kernel
configuration of transports without ifdef-hell.

Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2007-10-17 14:31:07 -05:00
Joe Korty 38e760a133 x86: expand /proc/interrupts to include missing vectors, v2
Add missing IRQs and IRQ descriptions to /proc/interrupts.

/proc/interrupts is most useful when it displays every IRQ vector in use by
the system, not just those somebody thought would be interesting.

This patch inserts the following vector displays to the i386 and x86_64
platforms, as appropriate:

	rescheduling interrupts
	TLB flush interrupts
	function call interrupts
	thermal event interrupts
	threshold interrupts
	spurious interrupts

A threshold interrupt occurs when ECC memory correction is occuring at too
high a frequency.  Thresholds are used by the ECC hardware as occasional
ECC failures are part of normal operation, but long sequences of ECC
failures usually indicate a memory chip that is about to fail.

Thermal event interrupts occur when a temperature threshold has been
exceeded for some CPU chip.  IIRC, a thermal interrupt is also generated
when the temperature drops back to a normal level.

A spurious interrupt is an interrupt that was raised then lowered by the
device before it could be fully processed by the APIC.  Hence the apic sees
the interrupt but does not know what device it came from.  For this case
the APIC hardware will assume a vector of 0xff.

Rescheduling, call, and TLB flush interrupts are sent from one CPU to
another per the needs of the OS.  Typically, their statistics would be used
to discover if an interrupt flood of the given type has been occuring.

AK: merged v2 and v4 which had some more tweaks
AK: replace Local interrupts with Local timer interrupts
AK: Fixed description of interrupt types.

[ tglx: arch/x86 adaptation ]
[ mingo: small cleanup ]

Signed-off-by: Joe Korty <joe.korty@ccur.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Tim Hockin <thockin@hockin.org>
Cc: Andi Kleen <ak@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-17 20:16:53 +02:00
Denis Cheng 5d4b355933 Documentation: add entries to filesystems/00-INDEX for several untracked files
Signed-off-by: Denis Cheng <crquan@gmail.com>
Cc: Rob Landley <rob@landley.net>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:43:05 -07:00
Jan Kara 8e8934695d quota: send messages via netlink
Implement sending of quota messages via netlink interface.  The advantage
is that in userspace we can better decide what to do with the message - for
example display a dialogue in your X session or just write the message to
the console.  As a bonus, we can get rid of problems with console locking
deep inside filesystem code once we remove the old printing mechanism.

Signed-off-by: Jan Kara <jack@suse.cz>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:42:56 -07:00
Randy Dunlap 1810732e94 docs: ramdisk/initrd/initramfs corrections
initrd/initramfs/ramdisk docs:
- fix typos/spellos/grammar
- clarify RAM disk config location
- correct cpio option

Acked-by: Bryan O'Sullivan <bos@serpentine.com>
Acked-by: Rob Landley <rob@landley.net>
Cc: Werner Almesberger <werner@almesberger.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:42:56 -07:00
Nick Piggin 55144768e1 fs: remove some AOP_TRUNCATED_PAGE
prepare/commit_write no longer returns AOP_TRUNCATED_PAGE since OCFS2 and
GFS2 were converted to the new aops, so we can make some simplifications
for that.

[michal.k.k.piotrowski@gmail.com: fix warning]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Michal Piotrowski <michal.k.k.piotrowski@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:42:58 -07:00
Nick Piggin afddba49d1 fs: introduce write_begin, write_end, and perform_write aops
These are intended to replace prepare_write and commit_write with more
flexible alternatives that are also able to avoid the buffered write
deadlock problems efficiently (which prepare_write is unable to do).

[mark.fasheh@oracle.com: API design contributions, code review and fixes]
[akpm@linux-foundation.org: various fixes]
[dmonakhov@sw.ru: new aop block_write_begin fix]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: Dmitriy Monakhov <dmonakhov@openvz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:42:55 -07:00
Linus Torvalds 541010e4b8 Merge branch 'locks' of git://linux-nfs.org/~bfields/linux
* 'locks' of git://linux-nfs.org/~bfields/linux:
  nfsd: remove IS_ISMNDLCK macro
  Rework /proc/locks via seq_files and seq_list helpers
  fs/locks.c: use list_for_each_entry() instead of list_for_each()
  NFS: clean up explicit check for mandatory locks
  AFS: clean up explicit check for mandatory locks
  9PFS: clean up explicit check for mandatory locks
  GFS2: clean up explicit check for mandatory locks
  Cleanup macros for distinguishing mandatory locks
  Documentation: move locks.txt in filesystems/
  locks: add warning about mandatory locking races
  Documentation: move mandatory locking documentation to filesystems/
  locks: Fix potential OOPS in generic_setlease()
  Use list_first_entry in locks_wake_up_blocks
  locks: fix flock_lock_file() comment
  Memory shortage can result in inconsistent flocks state
  locks: kill redundant local variable
  locks: reverse order of posix_locks_conflict() arguments
2007-10-15 16:07:40 -07:00
Anton Altaparmakov bfab36e816 NTFS: Fix a mount time deadlock.
Big thanks go to Mathias Kolehmainen for reporting the bug, providing
debug output and testing the patches I sent him to get it working.

The fix was to stop calling ntfs_attr_set() at mount time as that causes
balance_dirty_pages_ratelimited() to be called which on systems with
little memory actually tries to go and balance the dirty pages which tries
to take the s_umount semaphore but because we are still in fill_super()
across which the VFS holds s_umount for writing this results in a
deadlock.

We now do the dirty work by hand by submitting individual buffers.  This
has the annoying "feature" that mounting can take a few seconds if the
journal is large as we have clear it all.  One day someone should improve
on this by deferring the journal clearing to a helper kernel thread so it
can be done in the background but I don't have time for this at the moment
and the current solution works fine so I am leaving it like this for now.

Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-12 09:16:30 -07:00
J. Bruce Fields 98257af5a2 Documentation: move locks.txt in filesystems/
This documentation (about file locking) belongs in filesystems/.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2007-10-09 18:32:45 -04:00
J. Bruce Fields 9efa68ed07 locks: add warning about mandatory locking races
The mandatory file locking implementation has long-standing races that
probably render it useless.  I know of no plans to fix them.  Till we
do, we should at least warn people.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2007-10-09 18:32:45 -04:00
J. Bruce Fields 4f3b19ca41 Documentation: move mandatory locking documentation to filesystems/
Shouldn't this mandatory-locking documentation be in the
Documentation/filesystems directory?

Give it a more descriptive name while we're at it, and update 00-INDEX
with a more inclusive description of Documentation/filesystems (which
has already talked about more than just individual filesystems).

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
2007-10-09 18:32:45 -04:00
Linus Torvalds 577107e8e4 Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2:
  ocfs2: Fix calculation of i_blocks during truncate
  [PATCH] ocfs2: Fix a wrong cluster calculation.
  [PATCH] ocfs2: fix mount option parsing
  ocfs2: update docs for new features
2007-09-11 17:23:16 -07:00
Rob Landley c811ac5366 Documentation/00-INDEX: notice ecryptfs.txt moved
ecryptfs.txt moved into filesystems, make 00-INDEX follow.

Signed-off-by: Rob Landley <rob@landley.net>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-09-11 17:21:19 -07:00
Mark Fasheh 10b0845bed ocfs2: update docs for new features
Update documentation listing ocfs2 features to reflect the current state of
the file system. Add missing descriptions for some mount options which ocfs2
supports.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
2007-09-11 11:38:25 -07:00
Eric Van Hensbergen 27a2a5ff41 9p: update maintainers and documentation
Updates to the MAINTAINERS file and documentation for 9p to point to the
swik wiki versus the outdated sf.net page.  Also updated some email addresses
and added pointers to papers which better describe the implementation and
application of the Linux 9p client.

Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2007-08-23 10:12:48 -05:00
Wyatt Banks 60fd4d6a19 Documentation: document HFSPlus
Documentation: document HFSPlus filesystem and its mount options.

Signed-off-by: Wyatt Banks <wyatt@banksresearch.com>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-31 15:39:38 -07:00
Yoann Padioleau dd00cc486a some kmalloc/memset ->kzalloc (tree wide)
Transform some calls to kmalloc/memset to a single kzalloc (or kcalloc).

Here is a short excerpt of the semantic patch performing
this transformation:

@@
type T2;
expression x;
identifier f,fld;
expression E;
expression E1,E2;
expression e1,e2,e3,y;
statement S;
@@

 x =
- kmalloc
+ kzalloc
  (E1,E2)
  ...  when != \(x->fld=E;\|y=f(...,x,...);\|f(...,x,...);\|x=E;\|while(...) S\|for(e1;e2;e3) S\)
- memset((T2)x,0,E1);

@@
expression E1,E2,E3;
@@

- kzalloc(E1 * E2,E3)
+ kcalloc(E1,E2,E3)

[akpm@linux-foundation.org: get kcalloc args the right way around]
Signed-off-by: Yoann Padioleau <padator@wanadoo.fr>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Acked-by: Russell King <rmk@arm.linux.org.uk>
Cc: Bryan Wu <bryan.wu@analog.com>
Acked-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Dave Airlie <airlied@linux.ie>
Acked-by: Roland Dreier <rolandd@cisco.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Acked-by: Pierre Ossman <drzeus-list@drzeus.cx>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: "David S. Miller" <davem@davemloft.net>
Acked-by: Greg KH <greg@kroah.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 10:04:50 -07:00
Kawai, Hidehiro bb90110dcb coredump masking: documentation for /proc/pid/coredump_filter
This patch adds the documentation for /proc/<pid>/coredump_filter.

Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: David Howells <dhowells@redhat.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 10:04:47 -07:00
Peter Zijlstra bdf4c48af2 audit: rework execve audit
The purpose of audit_bprm() is to log the argv array to a userspace daemon at
the end of the execve system call.  Since user-space hasn't had time to run,
this array is still in pristine state on the process' stack; so no need to
copy it, we can just grab it from there.

In order to minimize the damage to audit_log_*() copy each string into a
temporary kernel buffer first.

Currently the audit code requires that the full argument vector fits in a
single packet.  So currently it does clip the argv size to a (sysctl) limit,
but only when execve auditing is enabled.

If the audit protocol gets extended to allow for multiple packets this check
can be removed.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ollie Wild <aaw@google.com>
Cc: <linux-audit@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 10:04:45 -07:00
Nick Piggin d0217ac04c mm: fault feedback #1
Change ->fault prototype.  We now return an int, which contains
VM_FAULT_xxx code in the low byte, and FAULT_RET_xxx code in the next byte.
 FAULT_RET_ code tells the VM whether a page was found, whether it has been
locked, and potentially other things.  This is not quite the way he wanted
it yet, but that's changed in the next patch (which requires changes to
arch code).

This means we no longer set VM_CAN_INVALIDATE in the vma in order to say
that a page is locked which requires filemap_nopage to go away (because we
can no longer remain backward compatible without that flag), but we were
going to do that anyway.

struct fault_data is renamed to struct vm_fault as Linus asked. address
is now a void __user * that we should firmly encourage drivers not to use
without really good reason.

The page is now returned via a page pointer in the vm_fault struct.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 10:04:41 -07:00
Mark Fasheh ed2f2f9b3f Document ->page_mkwrite() locking
There seems to be very little documentation about this callback in general.
The locking in particular is a bit tricky, so it's worth having this in
writing.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 10:04:41 -07:00
Nick Piggin 54cb8821de mm: merge populate and nopage into fault (fixes nonlinear)
Nonlinear mappings are (AFAIKS) simply a virtual memory concept that encodes
the virtual address -> file offset differently from linear mappings.

->populate is a layering violation because the filesystem/pagecache code
should need to know anything about the virtual memory mapping.  The hitch here
is that the ->nopage handler didn't pass down enough information (ie.  pgoff).
 But it is more logical to pass pgoff rather than have the ->nopage function
calculate it itself anyway (because that's a similar layering violation).

Having the populate handler install the pte itself is likewise a nasty thing
to be doing.

This patch introduces a new fault handler that replaces ->nopage and
->populate and (later) ->nopfn.  Most of the old mechanism is still in place
so there is a lot of duplication and nice cleanups that can be removed if
everyone switches over.

The rationale for doing this in the first place is that nonlinear mappings are
subject to the pagefault vs invalidate/truncate race too, and it seemed stupid
to duplicate the synchronisation logic rather than just consolidate the two.

After this patch, MAP_NONBLOCK no longer sets up ptes for pages present in
pagecache.  Seems like a fringe functionality anyway.

NOPAGE_REFAULT is removed.  This should be implemented with ->fault, and no
users have hit mainline yet.

[akpm@linux-foundation.org: cleanup]
[randy.dunlap@oracle.com: doc. fixes for readahead]
[akpm@linux-foundation.org: build fix]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 10:04:41 -07:00
Josef 'Jeff' Sipek 5d91192e66 eCryptfs: Move ecryptfs docs into Documentation/filesystems/
Signed-off-by: Josef 'Jeff' Sipek <jsipek@cs.sunysb.edu>
Acked-by: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-17 10:23:08 -07:00
Mel Gorman ed7ed36517 handle kernelcore=: generic
This patch adds the kernelcore= parameter for x86.

Once all patches are applied, a new command-line parameter exist and a new
sysctl.  This patch adds the necessary documentation.

From: Yasunori Goto <y-goto@jp.fujitsu.com>

  When "kernelcore" boot option is specified, kernel can't boot up on ia64
  because of an infinite loop.  In addition, the parsing code can be handled
  in an architecture-independent manner.

  This patch uses common code to handle the kernelcore= parameter.  It is
  only available to architectures that support arch-independent zone-sizing
  (i.e.  define CONFIG_ARCH_POPULATES_NODE_MAP).  Other architectures will
  ignore the boot parameter.

[bunk@stusta.de: make cmdline_parse_kernelcore() static]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Acked-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-17 10:22:59 -07:00
Linus Torvalds add096909d Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2: (32 commits)
  [PATCH] ocfs2: zero_user_page conversion
  ocfs2: Support xfs style space reservation ioctls
  ocfs2: support for removing file regions
  ocfs2: update truncate handling of partial clusters
  ocfs2: btree support for removal of arbirtrary extents
  ocfs2: Support creation of unwritten extents
  ocfs2: support writing of unwritten extents
  ocfs2: small cleanup of ocfs2_write_begin_nolock()
  ocfs2: btree changes for unwritten extents
  ocfs2: abstract btree growing calls
  ocfs2: use all extent block suballocators
  ocfs2: plug truncate into cached dealloc routines
  ocfs2: simplify deallocation locking
  ocfs2: harden buffer check during mapping of page blocks
  ocfs2: shared writeable mmap
  ocfs2: factor out write aops into nolock variants
  ocfs2: rework ocfs2_buffered_write_cluster()
  ocfs2: take ip_alloc_sem during entire truncate
  ocfs2: Add "preferred slot" mount option
  [KJ PATCH] Replacing memset(<addr>,0,PAGE_SIZE) with clear_page() in fs/ocfs2/dlm/dlmrecovery.c
  ...
2007-07-16 10:52:55 -07:00
Borislav Petkov 422b14c2e2 update Documentation/filesystems/vfs.txt
Update Documentation/filesystems/vfs.txt

Signed-off-by: Borislav Petkov <bbpetkov@yahoo.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 09:05:51 -07:00
Borislav Petkov 0746aec3c7 update description in Documentation/filesystems/vfs.txt
Update the description of struct file_system_type and get_sb() in
Documentation/filesystems/vfs.txt to match the current code.

Signed-off-by: Borislav Petkov <bbpetkov@yahoo.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 09:05:48 -07:00
Kees Cook 18d96779d9 Documentation: /proc/$pid/stat files
Documentation for the /proc/$pid/stat file.

Signed-off-by: Kees Cook <kees@outflux.net>
Cc: Rob Landley <rob@landley.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 09:05:45 -07:00
Joel Becker 631d1febab configfs: config item dependancies.
Sometimes other drivers depend on particular configfs items.  For
example, ocfs2 mounts depend on a heartbeat region item.  If that
region item is removed with rmdir(2), the ocfs2 mount must BUG or go
readonly.  Not happy.

This provides two additional API calls: configfs_depend_item() and
configfs_undepend_item().  A client driver can call
configfs_depend_item() on an existing item to tell configfs that it is
depended on.  configfs will then return -EBUSY from rmdir(2) for that
item.  When the item is no longer depended on, the client driver calls
configfs_undepend_item() on it.

These API cannot be called underneath any configfs callbacks, as
they will conflict.  They can block and allocate.  A client driver
probably shouldn't calling them of its own gumption.  Rather it should
be providing an API that external subsystems call.

How does this work?  Imagine the ocfs2 mount process.  When it mounts,
it asks for a heart region item.  This is done via a call into the
heartbeat code.  Inside the heartbeat code, the region item is looked
up.  Here, the heartbeat code calls configfs_depend_item().  If it
succeeds, then heartbeat knows the region is safe to give to ocfs2.
If it fails, it was being torn down anyway, and heartbeat can gracefully
pass up an error.

[ Fixed some bad whitespace in configfs.txt. --Mark ]

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
2007-07-10 17:18:59 -07:00
Joel Becker 299894cc90 configfs: accessing item hierarchy during rmdir(2)
Add a notification callback, ops->disconnect_notify(). It has the same
prototype as ->drop_item(), but it will be called just before the item
linkage is broken. This way, configfs users who want to do work while
the object is still in the heirarchy have a chance.

Client drivers will still need to config_item_put() in their
->drop_item(), if they implement it.  They need do nothing in
->disconnect_notify().  They don't have to provide it if they don't
care.  But someone who wants to be notified before ci_parent is set to
NULL can now be notified.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
2007-07-10 17:11:01 -07:00
Joel Becker e6bd07aee7 configfs: Convert subsystem semaphore to mutex
Convert the su_sem member of struct configfs_subsystem to a struct
mutex, as that's what it is. Also convert all the users and update
Documentation/configfs.txt and Documentation/configfs_example.c
accordingly.

[ Conflict in fs/dlm/config.c with commit
  3168b0780d manually resolved. --Mark ]

Inspired-by: Satyam Sharma <ssatyam@cse.iitk.ac.in>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
2007-07-10 17:10:56 -07:00
Hugh Dickins a210906c1b mount -t tmpfs -o mpol=: check nodes online
Randy Dunlap reports that a tmpfs, mounted with NUMA mpol= specifying an
offline node, crashes as soon as data is allocated upon it.  Now restrict it
to online nodes, where before it restricted to MAX_NUMNODES.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: Robin Holt <holt@sgi.com>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Andi Kleen <ak@suse.de>
Tested-and-acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-08 17:23:32 -07:00
Josef 'Jeff' Sipek c2b38989cf Documentation: Fix up docs still talking about i_sem
.. it got changed to 'i_mutex' some time ago.

Signed-off-by: Josef 'Jeff' Sipek <jsipek@cs.sunysb.edu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-24 10:16:17 -07:00
Artem Bityutskiy a7bc02f4f4 trivial: s/i_sem /i_mutex/
This patch substitutes i_sem by i_mutex in
Documentation/filesystems/Locking.
The patch also removes a couple of trailing white-spaces.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2007-05-09 08:58:17 +02:00
Matt LaPlante a982ac06b0 misc doc and kconfig typos
Fix various typos in kernel docs and Kconfigs, 2.6.21-rc4.

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2007-05-09 08:58:15 +02:00
Randy Dunlap 8b60756a62 Fix more "deprecated" spellos.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2007-05-09 07:19:14 +02:00
Linus Torvalds 18062a91d2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/shaggy/jfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/shaggy/jfs-2.6:
  JFS: Fix race waking up jfsIO kernel thread
  JFS: use __set_current_state()
  Copy i_flags to jfs inode flags on write
  JFS: document uid, gid, and umask mount options in jfs.txt
2007-05-08 11:32:30 -07:00
OGAWA Hirofumi 28ec039c21 fat: don't use free_clusters for fat32
It seems that the recent Windows changed specification, and it's
undocumented.  Windows doesn't update ->free_clusters correctly.

This patch doesn't use ->free_clusters by default.  (instead, add "usefree"
for forcing to use it)

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Juergen Beisert <juergen127@kreuzholzen.de>
Cc: Andreas Schwab <schwab@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:13 -07:00
Eric Dumazet c23fbb6bcb VFS: delay the dentry name generation on sockets and pipes
1) Introduces a new method in 'struct dentry_operations'.  This method
   called d_dname() might be called from d_path() to build a pathname for
   special filesystems.  It is called without locks.

   Future patches (if we succeed in having one common dentry for all
   pipes/sockets) may need to change prototype of this method, but we now
   use : char *d_dname(struct dentry *dentry, char *buffer, int buflen);

2) Adds a dynamic_dname() helper function that eases d_dname() implementations

3) Defines d_dname method for sockets : No more sprintf() at socket
   creation.  This is delayed up to the moment someone does an access to
   /proc/pid/fd/...

4) Defines d_dname method for pipes : No more sprintf() at pipe
   creation.  This is delayed up to the moment someone does an access to
   /proc/pid/fd/...

A benchmark consisting of 1.000.000 calls to pipe()/close()/close() gives a
*nice* speedup on my Pentium(M) 1.6 Ghz :

3.090 s instead of 3.450 s

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Acked-by: Christoph Hellwig <hch@infradead.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:03 -07:00
Kees Cook 5096add84b proc: maps protection
The /proc/pid/ "maps", "smaps", and "numa_maps" files contain sensitive
information about the memory location and usage of processes.  Issues:

- maps should not be world-readable, especially if programs expect any
  kind of ASLR protection from local attackers.
- maps cannot just be 0400 because "-D_FORTIFY_SOURCE=2 -O2" makes glibc
  check the maps when %n is in a *printf call, and a setuid(getuid())
  process wouldn't be able to read its own maps file.  (For reference
  see http://lkml.org/lkml/2006/1/22/150)
- a system-wide toggle is needed to allow prior behavior in the case of
  non-root applications that depend on access to the maps contents.

This change implements a check using "ptrace_may_attach" before allowing
access to read the maps contents.  To control this protection, the new knob
/proc/sys/kernel/maps_protect has been added, with corresponding updates to
the procfs documentation.

[akpm@linux-foundation.org: build fixes]
[akpm@linux-foundation.org: New sysctl numbers are old hat]
Signed-off-by: Kees Cook <kees@outflux.net>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:02 -07:00
David Rientjes b813e931b4 smaps: add clear_refs file to clear reference
Adds /proc/pid/clear_refs.  When any non-zero number is written to this file,
pte_mkold() and ClearPageReferenced() is called for each pte and its
corresponding page, respectively, in that task's VMAs.  This file is only
writable by the user who owns the task.

It is now possible to measure _approximately_ how much memory a task is using
by clearing the reference bits with

	echo 1 > /proc/pid/clear_refs

and checking the reference count for each VMA from the /proc/pid/smaps output
at a measured time interval.  For example, to observe the approximate change
in memory footprint for a task, write a script that clears the references
(echo 1 > /proc/pid/clear_refs), sleeps, and then greps for Pgs_Referenced and
extracts the size in kB.  Add the sizes for each VMA together for the total
referenced footprint.  Moments later, repeat the process and observe the
difference.

For example, using an efficient Mozilla:

	accumulated time		referenced memory
	----------------		-----------------
		 0 s				 408 kB
		 1 s				 408 kB
		 2 s				 556 kB
		 3 s				1028 kB
		 4 s				 872 kB
		 5 s				1956 kB
		 6 s				 416 kB
		 7 s				1560 kB
		 8 s				2336 kB
		 9 s				1044 kB
		10 s				 416 kB

This is a valuable tool to get an approximate measurement of the memory
footprint for a task.

Cc: Hugh Dickins <hugh@veritas.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Christoph Lameter <clameter@sgi.com>
Signed-off-by: David Rientjes <rientjes@google.com>
[akpm@linux-foundation.org: build fixes]
[mpm@selenic.com: rename for_each_pmd]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-07 12:12:52 -07:00
David Howells 0795e7c031 [AFS]: Update the AFS fs documentation.
Update the AFS fs documentation.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-26 15:57:43 -07:00
Stephen Hemminger a2a316fd06 [NET]: Replace CONFIG_NET_DEBUG with sysctl.
Covert network warning messages from a compile time to runtime choice.
Removes kernel config option and replaces it with new /proc/sys/net/core/warnings.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:24:05 -07:00
Dave Kleikamp ba863a0016 JFS: document uid, gid, and umask mount options in jfs.txt
Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
2007-03-09 10:27:31 -06:00
Roland Kletzing f9c99463b0 [PATCH] Documentation for io-accounting / reporting via procfs
Add some documentation for the new and very useful io-accounting feature.
It's being added to Documentation/filesystems/proc.txt

Signed-off-by: Roland Kletzing <devzero@web.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-05 07:57:54 -08:00
Nick Piggin 955eff5acc [PATCH] fs: fix libfs data leak
simple_prepare_write leaks uninitialised kernel data.  This happens because
the it leaves an uninitialised "hole" over the part of the page that the
write is expected to go to.  This is fine, but it then marks the page
uptodate, which means a concurrent read can come in and copy the
uninitialised memory into userspace before it written to.

Fix it by simply marking it uptodate in simple_commit_write instead, after
the hole has been filled in.  This could theoretically break an fs that
uses simple_prepare_write and not simple_commit_write, and that relies on
the incorrect simple_prepare_write behaviour.  Luckily, none of those
exists in the tree.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-20 17:10:15 -08:00
Linus Torvalds 2874b391bd Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs:
  9p: implement optional loose read cache
  9p: Use kthread_stop instead of sending a SIGKILL.
2007-02-19 13:33:01 -08:00
Eric Van Hensbergen e03abc0c96 9p: implement optional loose read cache
While cacheing is generally frowned upon in the 9p world, it has its
place -- particularly in situations where the remote file system is
exclusive and/or read-only.  The vacfs views of venti content addressable
store are a real-world instance of such a situation.  To facilitate higher
performance for these workloads (and eventually use the fscache patches),
we have enabled a "loose" cache mode which does not attempt to maintain
any form of consistency on the page-cache or dcache.  This results in over
two orders of magnitude performance improvement for cacheable block reads
in the Bonnie benchmark.  The more aggressive use of the dcache also seems
to improve metadata operational performance.

Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2007-02-18 10:16:10 -06:00
Uwe Kleine-König 1b3c3714cb Fix typos concerning hierarchy
heirarchical, hierachical -> hierarchical
        heirarchy, hierachy -> hierarchy

Signed-off-by: Uwe Kleine-König <zeisberg@informatik.uni-freiburg.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2007-02-17 19:23:03 +01:00
Evgeniy Dushistov cbcae39fa1 [PATCH] ufs2 write: mount as rw
These series of patches add UFS2 write-support.  UFS2 - is default file system
for recent versions of FreeBSD.

The main differences from UFS1 from write support point of view
are:
1)Not all inodes are allocated during formatation of disk.
2)All meta-data(pointer to data blocks) are 64bit(in UFS1 they
are 32bit).

So patch series consist of
1)make possible mount UFS2 in read-write mode
2)code to write ufs2 inodes and code to initialize inodes chunks.
3)work with 64bit meta-data

I made simple testing like create/deleting/writing/reading/truncating, also I
ran fsx-linux and untar and build kernel on UFS1 and UFS2, after that FreeBSD
fsck do not find any errors in fs.

This patch makes possible to mount ufs2 "rw", and updates UFS2 documentation:
remove note about bug(it fixed by reallocate blocks on the fly patch) and add
me in the list of people who want receive bug reports.

Signed-off-by: Evgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:40 -08:00
Mathieu Desnoyers 23c887522e [PATCH] Relay: add CPU hotplug support
Mathieu originally needed to add this for tracing Xen, but it's something
that's needed for any application that can be tracing while cpus are added.

unplug isn't supported by this patch.  The thought was that at minumum a new
buffer needs to be added when a cpu comes up, but it wasn't worth the effort
to remove buffers on cpu down since they'd be freed soon anyway when the
channel was closed.

[zanussi@us.ibm.com: avoid lock_cpu_hotplug deadlock]
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Tom Zanussi <zanussi@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:28 -08:00
Eric Van Hensbergen ff76e1dfc8 [PATCH] 9p: update documentation regarding server applications
Update the documentation to cover using Inferno as a server for 9p and to
include information about spfs (a stable single-threaded stand-alone 9p
server).

Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-01-26 13:50:59 -08:00
Anton Altaparmakov 8331191e56 NTFS: 2.1.28 - Fix deadlock reported by Sergey Vlasov due to ntfs_put_inode().
- Fix deadlock in fs/ntfs/inode.c::ntfs_put_inode().  Thanks to Sergey
  Vlasov for the report and detailed analysis of the deadlock.  The fix
  involved getting rid of ntfs_put_inode() altogether and hence NTFS no
  longer has a ->put_inode super operation.

Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
2007-01-18 09:42:48 +00:00
Trond Myklebust e3db7691e9 [PATCH] NFS: Fix race in nfs_release_page()
NFS: Fix race in nfs_release_page()

    invalidate_inode_pages2() may find the dirty bit has been set on a page
    owing to the fact that the page may still be mapped after it was locked.
    Only after the call to unmap_mapping_range() are we sure that the page
    can no longer be dirtied.
    In order to fix this, NFS has hooked the releasepage() method and tries
    to write the page out between the call to unmap_mapping_range() and the
    call to remove_mapping(). This, however leads to deadlocks in the page
    reclaim code, where the page may be locked without holding a reference
    to the inode or dentry.

    Fix is to add a new address_space_operation, launder_page(), which will
    attempt to write out a dirty page without releasing the page lock.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

    Also, the bare SetPageDirty() can skew all sort of accounting leading to
    other nasties.

[akpm@osdl.org: cleanup]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2007-01-11 18:18:21 -08:00
Alexey Dobriyan 91f6e54b6e [PATCH] fuse: fix typo
Signed-off-by: Thomas Hisch <t.hisch@gmail.com>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-30 10:56:45 -08:00
Tigran Aivazian 69688262fb [PATCH] update Tigran's email addresses
As Adrian pointed out recently, there were still a couple of places where
I should have fixed my email address.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-13 09:05:53 -08:00
Tiger Yang bcd5625bff ocfs2: update mount option documentation
We forgot to document the atime_quantum mount option in ocfs2.txt. This adds
a proper description of how it works.

Signed-off-by: Tiger Yang <tiger.yang@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
2006-12-07 17:48:41 -08:00
Adrian Bunk 3982cd99c3 [PATCH] fs/sysv/: doc cleanup
Remove two different changelog files from fs/sysv/ and merges the INTRO
file into Documentation/filesystems/sysv-fs.txt

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:44 -08:00
Vasily Averin 70888bd5b7 [PATCH] Documentation: remount_fs() needs lock_kernel
Fixed long-lived typo: remount_fs() needs BKL

Signed-off-by: Vasily Averin <vvs@sw.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:36 -08:00
Miklos Szeredi d809161402 [PATCH] fuse: add blksize option
Add 'blksize' option for block device based filesystems.  During
initialization this is used to set the block size on the device and the super
block.  The default block size is 512bytes.

Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:31 -08:00
Miklos Szeredi d6392f873f [PATCH] fuse: add support for block device based filesystems
I never intended this, but people started using fuse to implement block device
based "real" filesystems (ntfs-3g, zfs).

The following four patches add better support for these kinds of filesystems.
Unlike "normal" fuse filesystems, using this feature should require superuser
privileges (enforced by the fusermount utility).

Thanks to Szabolcs Szakacsits for the input and testing.

This patch adds a 'fuseblk' filesystem type, which is only different from the
'fuse' filesystem type in how the 'dev_name' mount argument is interpreted.

Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:31 -08:00
Matt LaPlante 5d3f083d8f Fix typos in /Documentation : Misc
This patch fixes typos in various Documentation txts. The patch addresses some
misc words.

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-11-30 05:21:10 +01:00
Matt LaPlante 4ae0edc21b Fix typos in /Documentation : 'U-Z'
This patch fixes typos in various Documentation txts. The patch addresses some
+words starting with the letters 'U-Z'.

Looks like I made it through the alphabet...just in time to start over again
+too!  Maybe I can fit more profound fixes into the next round...?  Time will
+tell. :)

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-11-30 04:58:40 +01:00
Matt LaPlante fa00e7e152 Fix typos in /Documentation : 'T''
This patch fixes typos in various Documentation txts. The patch addresses some
+words starting with the letter 'T'.

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-11-30 04:55:36 +01:00
Phillip Susi 55aa601e14 [PATCH] Update udf documentation to reflect current state of read/write support
Change Documentation/filesystems/udf.txt from saying that read/write mounts
on cd media are not supported to instead state the current level of
support.  Specifically that it works fine on dvd+rw media and can be made
to work on cd-rw media via the pktcdvd device.

Cc: Peter Osterlund <petero2@telia.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-16 11:43:38 -08:00
Dave Kleikamp fc513a333b [PATCH] Documentation/filesystems/ext4.txt
This file, ext4.txt, was put together with information from Andrew Morton,
Andreas Dilger, Suparna Bhattacharya, and Ted Ts'o.

I copied the mount options, with the exception of "extents", from ext3.txt,
so if anyone is aware of anything out-of-date, please let me know.

Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Suparna Bhattacharya <suparna@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-11 11:14:19 -07:00
Linus Torvalds 4a61f17378 Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6: (292 commits)
  [GFS2] Fix endian bug for de_type
  [GFS2] Initialize SELinux extended attributes at inode creation time.
  [GFS2] Move logging code into log.c (mostly)
  [GFS2] Mark nlink cleared so VFS sees it happen
  [GFS2] Two redundant casts removed
  [GFS2] Remove uneeded endian conversion
  [GFS2] Remove duplicate sb reading code
  [GFS2] Mark metadata reads for blktrace
  [GFS2] Remove iflags.h, use FS_
  [GFS2] Fix code style/indent in ops_file.c
  [GFS2] streamline-generic_file_-interfaces-and-filemap gfs fix
  [GFS2] Remove readv/writev methods and use aio_read/aio_write instead (gfs bits)
  [GFS2] inode-diet: Eliminate i_blksize from the inode structure
  [GFS2] inode_diet: Replace inode.u.generic_ip with inode.i_private (gfs)
  [GFS2] Fix typo in last patch
  [GFS2] Fix direct i/o logic in filemap.c
  [GFS2] Fix bug in Makefiles for lock modules
  [GFS2] Remove (extra) fs_subsys declaration
  [GFS2/DLM] Fix trailing whitespace
  [GFS2] Tidy up meta_io code
  ...
2006-10-04 09:06:16 -07:00
Paolo Ornati 670e9f34ee Documentation: remove duplicated words
Remove many duplicated words under Documentation/ and do other small
cleanups.

Examples:
        "and and" --> "and"
        "in in" --> "in"
        "the the" --> "the"
        "the the" --> "to the"
        ...

Signed-off-by: Paolo Ornati <ornati@fastwebnet.it>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-10-03 22:57:56 +02:00