Commit Graph

62 Commits

Author SHA1 Message Date
Linus Torvalds
f13771187b Merge branch 'bkl/ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing
* 'bkl/ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing:
  uml: Pushdown the bkl from harddog_kern ioctl
  sunrpc: Pushdown the bkl from sunrpc cache ioctl
  sunrpc: Pushdown the bkl from ioctl
  autofs4: Pushdown the bkl from ioctl
  uml: Convert to unlocked_ioctls to remove implicit BKL
  ncpfs: BKL ioctl pushdown
  coda: Clean-up whitespace problems in pioctl.c
  coda: BKL ioctl pushdown
  drivers: Push down BKL into various drivers
  isdn: Push down BKL into ioctl functions
  scsi: Push down BKL into ioctl functions
  dvb: Push down BKL into ioctl functions
  smbfs: Push down BKL into ioctl function
  coda/psdev: Remove BKL from ioctl function
  um/mmapper: Remove BKL usage
  sn_hwperf: Kill BKL usage
  hfsplus: Push down BKL into ioctl function
2010-05-24 08:01:10 -07:00
Frederic Weisbecker
9918ff26b3 sunrpc: Pushdown the bkl from sunrpc cache ioctl
Pushdown the bkl to cache_ioctl_pipefs.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Nfs <linux-nfs@vger.kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
2010-05-22 17:44:20 +02:00
Linus Torvalds
f72caf7e49 Merge branch 'for-2.6.35' of git://linux-nfs.org/~bfields/linux
* 'for-2.6.35' of git://linux-nfs.org/~bfields/linux: (45 commits)
  Revert "nfsd4: distinguish expired from stale stateids"
  nfsd: safer initialization order in find_file()
  nfs4: minor callback code simplification, comment
  NFSD: don't report compiled-out versions as present
  nfsd4: implement reclaim_complete
  nfsd4: nfsd4_destroy_session must set callback client under the state lock
  nfsd4: keep a reference count on client while in use
  nfsd4: mark_client_expired
  nfsd4: introduce nfs4_client.cl_refcount
  nfsd4: refactor expire_client
  nfsd4: extend the client_lock to cover cl_lru
  nfsd4: use list_move in move_to_confirmed
  nfsd4: fold release_session into expire_client
  nfsd4: rename sessionid_lock to client_lock
  nfsd4: fix bare destroy_session null dereference
  nfsd4: use local variable in nfs4svc_encode_compoundres
  nfsd: further comment typos
  sunrpc: centralise most calls to svc_xprt_received
  nfsd4: fix unlikely race in session replay case
  nfsd4: fix filehandle comment
  ...
2010-05-19 17:24:54 -07:00
Frederic Weisbecker
99df95a22f sunrpc: Include missing smp_lock.h
Now that cache_ioctl_procfs() calls the bkl explicitly, we need to
include the relevant header as well.

This fixes the following build error:

	net/sunrpc/cache.c: In function 'cache_ioctl_procfs':
	net/sunrpc/cache.c:1355: error: implicit declaration of function 'lock_kernel'
	net/sunrpc/cache.c:1359: error: implicit declaration of function 'unlock_kernel'

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-05-17 03:06:31 +02:00
Frederic Weisbecker
d79b6f4de5 procfs: Push down the bkl from ioctl
Push down the bkl from procfs's ioctl main handler to its users.
Only three procfs users implement an ioctl (non unlocked) handler.
Turn them into unlocked_ioctl and push down the Devil inside.

v2: PDE(inode)->data doesn't need to be under bkl
v3: And don't forget to git-add the result
v4: Use wrappers to pushdown instead of an invasive and error prone
    handlers surgery.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: John Kacur <jkacur@redhat.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
2010-05-17 03:06:12 +02:00
Li Zefan
a5990ea125 sunrpc/cache: fix module refcnt leak in a failure path
Don't forget to release the module refcnt if seq_open() returns failure.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: J. Bruce Fields <bfields@fieldses.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-03-24 10:40:46 -04:00
NeilBrown
d202cce896 sunrpc: never return expired entries in sunrpc_cache_lookup
If sunrpc_cache_lookup finds an expired entry, remove it from
the cache and return a freshly created non-VALID entry instead.
This ensures that we only ever get a usable entry, or an
entry that will become usable once an update arrives.
i.e. we will never need to repeat the lookup.

This allows us to remove the 'is_expired' test from cache_check
(i.e. from cache_is_valid).  cache_check should never get an expired
entry as 'lookup' will never return one.  If it does happen - due to
inconvenient timing - then just accept it as still valid, it won't be
very much past it's use-by date.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-03-14 21:48:52 -04:00
NeilBrown
2f50d8b63d sunrpc/cache: factor out cache_is_expired
This removes a tiny bit of code duplication, but more important
prepares for following patch which will perform the expiry check in
cache_lookup and the rest of the validity check in cache_check.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-03-14 18:08:37 -04:00
NeilBrown
3af4974eb2 sunrpc: don't keep expired entries in the auth caches.
currently expired entries remain in the auth caches as long
as there is a reference.
This was needed long ago when the auth_domain cache used the same
cache infrastructure.  But since that (being a very different sort
of cache) was separated, this test is no longer needed.

So remove the test on refcnt and tidy up the surrounding code.

This allows the cache_dequeue call (which needed to be there to
drop a potentially awkward reference) can be moved outside of the
spinlock which is a better place for it.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-03-14 18:03:54 -04:00
Joe Perches
f64f9e7192 net: Move && and || to end of previous line
Not including net/atm/

Compiled tested x86 allyesconfig only
Added a > 80 column line or two, which I ignored.
Existing checkpatch plaints willfully, cheerfully ignored.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-29 16:55:45 -08:00
NeilBrown
cd68c374ea sunrpc/cache: avoid variable over-loading in cache_defer_req
In cache_defer_req, 'dreq' is used for two significantly different
values that happen to be of the same type.

This is both confusing, and makes it hard to extend the range of one of
the values as we will in the next patch.
So introduce 'discard' to take one of the values.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-09-18 17:01:12 -04:00
NeilBrown
67e7328f15 sunrpc/cache: use list_del_init for the list_head entries in cache_deferred_req
Using list_del_init is generally safer than list_del, and it will
allow us, in a subsequent patch, to see if an entry has already been
processed or not.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-09-18 11:47:49 -04:00
NeilBrown
908329f2c0 sunrpc/cache: simplify cache_fresh_locked and cache_fresh_unlocked.
The extra call to cache_revisit_request in cache_fresh_unlocked is not
needed, as should have been fairly clear at the time of
   commit 4013edea9a

If there are requests to be revisited, then we can be sure that
CACHE_PENDING is set, so the second call is sufficient.

So remove the first call.
Then remove the 'new' parameter,
then remove the return value for cache_fresh_locked which is only used
to provide the value for 'new'.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-09-11 17:08:54 -04:00
NeilBrown
9e4c6379a6 sunrpc/cache: change cache_defer_req to return -ve error, not boolean.
As "cache_defer_req" does not sound like a predicate, having it return
a boolean value can be confusing.  It is more consistent to return
0 for success and negative for error.

Exactly what error code to return is not important as we don't
differentiate between reasons why the request wasn't deferred,
we only care about whether it was deferred or not.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-09-11 17:03:27 -04:00
J. Bruce Fields
e9dc122166 Merge branch 'nfs-for-2.6.32' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6 into for-2.6.32-incoming
Conflicts:
	net/sunrpc/cache.c
2009-08-21 11:27:29 -04:00
Trond Myklebust
f7e86ab92f SUNRPC: cache must take a reference to the cache detail's module on open()
Otherwise we Oops if the module containing the cache detail is removed
before all cache readers have closed the file.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-08-19 18:22:16 -04:00
Trond Myklebust
8854e82d9a SUNRPC: Add an rpc_pipefs front end for the sunrpc cache code
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-08-09 15:14:30 -04:00
Trond Myklebust
173912a6ad SUNRPC: Move procfs-specific stuff out of the generic sunrpc cache code
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-08-09 15:14:29 -04:00
Trond Myklebust
bc74b4f5e6 SUNRPC: Allow the cache_detail to specify alternative upcall mechanisms
For events that are rare, such as referral DNS lookups, it makes limited
sense to have a daemon constantly listening for upcalls on a channel. An
alternative in those cases might simply be to run the app that fills the
cache using call_usermodehelper_exec() and friends.

The following patch allows the cache_detail to specify alternative upcall
mechanisms for these particular cases.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-08-09 15:14:29 -04:00
Trond Myklebust
da77005f0d SUNRPC: Remove the global temporary write buffer in net/sunrpc/cache.c
While we do want to protect against multiple concurrent readers and writers
on each upcall/downcall pipe, we don't want to limit concurrent reading and
writing to separate caches.

This patch therefore replaces the static buffer 'write_buf', which can only
be used by one writer at a time, with use of the page cache as the
temporary buffer for downcalls. We still fall back to using the the old
global buffer if the downcall is larger than PAGE_CACHE_SIZE, since this is
apparently needed by the SPKM security context initialisation.

It then replaces the use of the global 'queue_io_mutex' with the
inode->i_mutex in cache_read() and cache_write().

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-08-09 15:14:28 -04:00
Trond Myklebust
5b7a1b9f92 SUNRPC: Ensure we initialise the cache_detail before creating procfs files
Also ensure that we destroy those files before we destroy the cache_detail.
Otherwise, user processes might attempt to write into uninitialised caches.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-08-09 15:14:27 -04:00
Trond Myklebust
2da8ca26c6 NFSD: Clean up the idmapper warning...
What part of 'internal use' is so hard to understand?

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-08-09 15:14:26 -04:00
NeilBrown
989a19b9b1 sunrpc/cache: recheck cache validity after cache_defer_req
If cache_defer_req did not leave the request on a queue, then it could
possibly have waited long enough that the cache became valid.  So check the
status after the call.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-08-04 16:21:44 -04:00
NeilBrown
5c4d263903 sunrpc/cache: make sure deferred requests eventually get revisited.
While deferred requests normally get revisited quite quickly,
it is possible for a request to remain in the deferral queue
when the cache item is discarded.  We can easily make sure that
doesn't happen by calling cache_revisit_request just before
the final 'put'.

Also there is a small chance that a race would cause one thread to
defer a request against a cache item while another thread is failing
to queue an upcall for that item.  So when the upcall fails, make
sure to revisit all deferred requests.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-08-04 11:03:01 -04:00
NeilBrown
f866a8194f sunrpc/cache: rename queue_loose to cache_dequeue
'loose' was a mis-spelling of 'lose', and even that wasn't a good
word choice.
So give this function a more useful name.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-08-04 09:14:30 -04:00
Anton Blanchard
6aad89c837 sunrpc: align cache_clean work's timer
Align cache_clean work.

Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-06-15 18:14:58 -07:00
Alexey Dobriyan
99b7623380 proc 2/2: remove struct proc_dir_entry::owner
Setting ->owner as done currently (pde->owner = THIS_MODULE) is racy
as correctly noted at bug #12454. Someone can lookup entry with NULL
->owner, thus not pinning enything, and release it later resulting
in module refcount underflow.

We can keep ->owner and supply it at registration time like ->proc_fops
and ->data.

But this leaves ->owner as easy-manipulative field (just one C assignment)
and somebody will forget to unpin previous/pin current module when
switching ->owner. ->proc_fops is declared as "const" which should give
some thoughts.

->read_proc/->write_proc were just fixed to not require ->owner for
protection.

rmmod'ed directories will be empty and return "." and ".." -- no harm.
And directories with tricky enough readdir and lookup shouldn't be modular.
We definitely don't want such modular code.

Removing ->owner will also make PDE smaller.

So, let's nuke it.

Kudos to Jeff Layton for reminding about this, let's say, oversight.

http://bugzilla.kernel.org/show_bug.cgi?id=12454

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-03-31 01:14:44 +04:00
Trond Myklebust
24c3767e41 SUNRPC: The sunrpc server code should not be used by out-of-tree modules
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-07 17:18:42 -05:00
Denis V. Lunev
e7fe23363b sunrpc: assign PDE->data before gluing PDE into /proc tree
Simply replace proc_create and further data assigned with proc_create_data.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-05-02 02:44:36 -07:00
J. Bruce Fields
67eb6ff610 svcrpc: move unused field from cache_deferred_req
This field is set once and never used; probably some artifact of an
earlier implementation idea.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-04-23 16:13:37 -04:00
Wang Chen
2ce8f047d5 [SUNRPC]: Use proc_create() to setup ->proc_fops first
Use proc_create() to make sure that ->proc_fops be setup before gluing
PDE to main tree.

Signed-off-by: Wang Chen <wangchen@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-28 14:00:59 -08:00
Trond Myklebust
d2f7e79e3b SUNRPC: Move exported symbol definitions after function declaration part 2
Do it for the server code...

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01 17:01:24 -05:00
J. Bruce Fields
dbf847ecb6 knfsd: allow cache_register to return error on failure
Newer server features such as nfsv4 and gss depend on proc to work, so a
failure to initialize the proc files they need should be treated as
fatal.

Thanks to Andrew Morton for style fix and compile fix in case where
CONFIG_NFSD_V4 is undefined.

Cc: Andrew Morton <akpm@linux-foundation.org>
Acked-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01 16:42:05 -05:00
J. Bruce Fields
ffe9386b6e nfsd: move cache proc (un)registration to separate function
Just some minor cleanup.

Also I don't see much point in trying to register further proc entries
if initial entries fail; so just stop trying in that case.

Acked-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01 16:42:04 -05:00
J. Bruce Fields
df95a9d4fb knfsd: cache unregistration needn't return error
There's really nothing much the caller can do if cache unregistration
fails.  And indeed, all any caller does in this case is print an error
and continue.  So just return void and move the printk's inside
cache_unregister.

Acked-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01 16:42:04 -05:00
J. Bruce Fields
a490c681cb knfsd: fix cache.c comment
The path here must be left over from some earlier draft; fix it.  And do
some more minor cleanup while we're there.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01 16:42:03 -05:00
Chuck Lever
01b2969a85 SUNRPC: Prevent length underflow in read_flush()
Make sure we compare an unsigned length to an unsigned count in
read_flush().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01 16:42:02 -05:00
Eric Dumazet
9a429c4983 [NET]: Add some acquires/releases sparse annotations.
Add __acquires() and __releases() annotations to suppress some sparse
warnings.

example of warnings :

net/ipv4/udp.c:1555:14: warning: context imbalance in 'udp_seq_start' - wrong
count at exit
net/ipv4/udp.c:1571:13: warning: context imbalance in 'udp_seq_stop' -
unexpected unlock

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 15:00:31 -08:00
Pavel Emelyanov
ec93103519 [SUNRPC]: Make the sunrpc use the seq_open_private()
Just switch to the consolidated code.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:55:36 -07:00
Trond Myklebust
4011cd9788 SUNRPC: Replace flush_workqueue() with cancel_work_sync() and friends
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-08-07 16:13:01 -04:00
Philippe De Muyter
56b3d975bb [NET]: Make all initialized struct seq_operations const.
Make all initialized struct seq_operations in net/ const

Signed-off-by: Philippe De Muyter <phdm@macqel.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 23:07:31 -07:00
Martin Peschke
14690fc649 [SUNRPC]: cleanup: use seq_release_private() where appropriate
We can save some lines of code by using seq_release_private().

Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Acked-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-26 01:03:43 -07:00
Trond Myklebust
d9bc125caf Merge branch 'master' of /home/trondmy/kernel/linux-2.6/
Conflicts:

	net/sunrpc/auth_gss/gss_krb5_crypto.c
	net/sunrpc/auth_gss/gss_spkm3_token.c
	net/sunrpc/clnt.c

Merge with mainline and fix conflicts.
2007-02-12 22:43:25 -08:00
Arjan van de Ven
da7071d7e3 [PATCH] mark struct file_operations const 8
Many struct file_operations in the kernel can be "const".  Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data.  In addition it'll catch accidental writes at compile time to
these shared resources.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:46 -08:00
YOSHIFUJI Hideaki
cca5172a7e [NET] SUNRPC: Fix whitespace errors.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-10 23:20:13 -08:00
Chuck Lever
46121cf7d8 SUNRPC: fix print format for tk_pid
The tk_pid field is an unsigned short.  The proper print format specifier for
that type is %5u, not %4d.

Also clean up some miscellaneous print formatting nits.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-02-03 15:35:10 -08:00
J.Bruce Fields
01f3bd1f03 [PATCH] knfsd: svcrpc: remove another silent drop from deferral code
There's no point deferring something just to immediately fail the deferral,
especially now that we can do something more useful in the failure case by
returning an error.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-13 09:05:54 -08:00
J.Bruce Fields
e0bb89ef03 [PATCH] knfsd: nfsd: don't drop silently on upcall deferral
To avoid tying up server threads when nfsd makes an upcall (to mountd, to get
export options, to idmapd, for nfsv4 name<->id mapping, etc.), we temporarily
"drop" the request and save enough information so that we can revisit it
later.

Certain failures during the deferral process can cause us to really drop the
request and never revisit it.

This is often less than ideal, and is unacceptable in the NFSv4 case--rfc 3530
forbids the server from dropping a request without also closing the
connection.

As a first step, we modify the deferral code to return -ETIMEDOUT (which is
translated to nfserr_jukebox in the v3 and v4 cases, and remains a drop in the
v2 case).

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-13 09:05:54 -08:00
Josef Sipek
303b46bb77 [PATCH] struct path: convert sunrpc
Signed-off-by: Josef Sipek <jsipek@fsl.cs.sunysb.edu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:28:50 -08:00
David Howells
65f27f3844 WorkStruct: Pass the work_struct pointer instead of context data
Pass the work_struct pointer to the work function rather than context data.
The work function can use container_of() to work out the data.

For the cases where the container of the work_struct may go away the moment the
pending bit is cleared, it is made possible to defer the release of the
structure by deferring the clearing of the pending bit.

To make this work, an extra flag is introduced into the management side of the
work_struct.  This governs auto-release of the structure upon execution.

Ordinarily, the work queue executor would release the work_struct for further
scheduling or deallocation by clearing the pending bit prior to jumping to the
work function.  This means that, unless the driver makes some guarantee itself
that the work_struct won't go away, the work function may not access anything
else in the work_struct or its container lest they be deallocated..  This is a
problem if the auxiliary data is taken away (as done by the last patch).

However, if the pending bit is *not* cleared before jumping to the work
function, then the work function *may* access the work_struct and its container
with no problems.  But then the work function must itself release the
work_struct by calling work_release().

In most cases, automatic release is fine, so this is the default.  Special
initiators exist for the non-auto-release case (ending in _NAR).


Signed-Off-By: David Howells <dhowells@redhat.com>
2006-11-22 14:55:48 +00:00