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* Merge branch 'for-2.6.39' of git://linux-nfs.org/~bfields/linuxLinus Torvalds2011-03-24
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 'for-2.6.39' of git://linux-nfs.org/~bfields/linux: SUNRPC: Remove resource leak in svc_rdma_send_error() nfsd: wrong index used in inner loop nfsd4: fix comment and remove unused nfsd4_file fields nfs41: make sure nfs server return right ca_maxresponsesize_cached nfsd: fix compile error svcrpc: fix bad argument in unix_domain_find nfsd4: fix struct file leak nfsd4: minor nfs4state.c reshuffling svcrpc: fix rare race on unix_domain creation nfsd41: modify the members value of nfsd4_op_flags nfsd: add proc file listing kernel's gss_krb5 enctypes gss:krb5 only include enctype numbers in gm_upcall_enctypes NFSD, VFS: Remove dead code in nfsd_rename() nfsd: kill unused macro definition locks: use assign_type()
| * locks: use assign_type()Namhyung Kim2011-03-07
| | | | | | | | | | Signed-off-by: Namhyung Kim <namhyung@gmail.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
* | fs/locks.c: Remove stale FIXME left over from BKL conversionMatt Fleming2011-03-05
|/ | | | | | | | | The comment is no longer true as (now that the BKL conversion is finished) a spinlock _is_ now used to protect file_lock_list, blocked_list and inode->i_flock. Signed-off-by: Matt Fleming <matt.fleming@linux.intel.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
* Merge branch 'for-2.6.38' of git://linux-nfs.org/~bfields/linuxLinus Torvalds2011-01-14
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 'for-2.6.38' of git://linux-nfs.org/~bfields/linux: (62 commits) nfsd4: fix callback restarting nfsd: break lease on unlink, link, and rename nfsd4: break lease on nfsd setattr nfsd: don't support msnfs export option nfsd4: initialize cb_per_client nfsd4: allow restarting callbacks nfsd4: simplify nfsd4_cb_prepare nfsd4: give out delegations more quickly in 4.1 case nfsd4: add helper function to run callbacks nfsd4: make sure sequence flags are set after destroy_session nfsd4: re-probe callback on connection loss nfsd4: set sequence flag when backchannel is down nfsd4: keep finer-grained callback status rpc: allow xprt_class->setup to return a preexisting xprt rpc: keep backchannel xprt as long as server connection rpc: move sk_bc_xprt to svc_xprt nfsd4: allow backchannel recovery nfsd4: support BIND_CONN_TO_SESSION nfsd4: modify session list under cl_lock Documentation: fl_mylease no longer exists ... Fix up conflicts in fs/nfsd/vfs.c with the vfs-scale work. The vfs-scale work touched some msnfs cases, and this merge removes support for that entirely, so the conflict was trivial to resolve.
| * locks: minor setlease cleanupJ. Bruce Fields2011-01-04
| | | | | | | | Signed-off-by: J. Bruce Fields <bfields@redhat.com>
| * locks: eliminate fl_mylease callbackJ. Bruce Fields2011-01-04
| | | | | | | | | | | | | | | | | | | | The nfs server only supports read delegations for now, so we don't care how conflicts are determined. All we care is that unlocks are recognized as matching the leases they are meant to remove. After the last patch, a comparison of struct files will work for that purpose. So we no longer need this callback. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
* | fs: dcache scale dentry refcountNick Piggin2011-01-07
|/ | | | | | | | Make d_count non-atomic and protect it with d_lock. This allows us to ensure a 0 refcount dentry remains 0 without dcache_lock. It is also fairly natural when we start protecting many other dentry members with d_lock. Signed-off-by: Nick Piggin <npiggin@kernel.dk>
* BKL: remove extraneous #include <smp_lock.h>Arnd Bergmann2010-11-17
| | | | | | | | | | The big kernel lock has been removed from all these files at some point, leaving only the #include. Remove this too as a cleanup. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* locks: remove dead lease error-handling codeJ. Bruce Fields2010-11-10
| | | | | | | | | A minor oversight from f7347ce4ee7c65415f84be915c018473e7076f31, "fasync: re-organize fasync entry insertion to allow it under a spinlock": this cleanup-on-error was only needed to handle -ENOMEM. Now that we're preallocating it's unneeded. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
* locks: fix leak on merging leasesJ. Bruce Fields2010-11-10
| | | | | | | | | | We must also free the passed-in lease in the case it wasn't used because an existing lease was upgrade/downgraded or already existed. Note the nfsd caller doesn't care because it's fl_change callback returns an error in those cases. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
* locks: remove fl_copy_lock lock_manager operationChristoph Hellwig2010-10-31
| | | | | | | | This one was only used for a nasty hack in nfsd, which has recently been removed. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* locks: let the caller free file_lock on ->setlease failureChristoph Hellwig2010-10-31
| | | | | | | | | | | | The caller allocated it, the caller should free it. The only issue so far is that we could change the flp pointer even on an error return if the fl_change callback failed. But we can simply move the flp assignment after the fl_change invocation, as the callers don't care about the flp return value if the setlease call failed. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* locks: fix setlease methods to free passed-in lockJ. Bruce Fields2010-10-30
| | | | | | | | | | | | | We modified setlease to require the caller to allocate the new lease in the case of creating a new lease, but forgot to fix up the filesystem methods. Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Steve French <sfrench@samba.org> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* locks: fix leaks on setlease errorsJ. Bruce Fields2010-10-30
| | | | | | | | We're depending on setlease to free the passed-in lease on failure. Signed-off-by: J. Bruce Fields <bfields@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* locks: prevent ENOMEM on lease unlockJ. Bruce Fields2010-10-30
| | | | | | | | | | | | | Removing a lock shouldn't require any allocations; a failure due to ENOMEM leaves the caller with a choice between retrying or giving up and leaking an unused lease. Next we should split the other lease calls into add and delete cases. I wanted to start with just the bugfix. Signed-off-by: J. Bruce Fields <bfields@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'flock' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bklLinus Torvalds2010-10-27
|\ | | | | | | | | | | | | | | | | * 'flock' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl: locks: turn lock_flocks into a spinlock fasync: re-organize fasync entry insertion to allow it under a spinlock locks/nfsd: allocate file lock outside of spinlock lockd: fix nlmsvc_notify_blocked locking lockd: push lock_flocks down
| * locks: turn lock_flocks into a spinlockArnd Bergmann2010-10-27
| | | | | | | | | | | | | | | | Nothing depends on lock_flocks using the BKL any more, so we can do the switch over to a private spinlock. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
| * fasync: re-organize fasync entry insertion to allow it under a spinlockLinus Torvalds2010-10-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | You currently cannot use "fasync_helper()" in an atomic environment to insert a new fasync entry, because it will need to allocate the new "struct fasync_struct". Yet fcntl_setlease() wants to call this under lock_flocks(), which is in the process of being converted from the BKL to a spinlock. In order to fix this, this abstracts out the actual fasync list insertion and the fasync allocations into functions of their own, and teaches fs/locks.c to pre-allocate the fasync_struct entry. That way the actual list insertion can happen while holding the required spinlock. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> [bfields@redhat.com: rebase on top of my changes to Arnd's patch] Tested-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
| * locks/nfsd: allocate file lock outside of spinlockArnd Bergmann2010-10-27
| | | | | | | | | | | | | | | | | | | | | | As suggested by Christoph Hellwig, this moves allocation of new file locks out of generic_setlease into the callers, nfs4_open_delegation and fcntl_setlease in order to allow GFP_KERNEL allocations when lock_flocks has become a spinlock. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: J. Bruce Fields <bfields@redhat.com>
* | procfs: fix numbering in /proc/locksJerome Marchand2010-10-26
|/ | | | | | | | | | | | | | | | | | | | | The lock number in /proc/locks (first field) is implemented by a counter (private field of struct seq_file) which is incremented at each call of locks_show() and reset to 1 in locks_start() whatever the offset is. It should be reset according to the actual position in the list. Because of this, the numbering erratically restarts at 1 several times when reading a long /proc/locks file. Moreover, locks_show() can be called twice to print a single line thus skipping a number. The counter should be incremented in locks_next(). And last, pos is a loff_t, which can be bigger than a pointer, so we don't use the pointer as an integer anymore, and allocate a loff_t instead. Signed-off-by: Jerome Marchand <jmarchan@redhat.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Matthew Wilcox <matthew@wil.cx> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* fs/locks.c: prepare for BKL removalArnd Bergmann2010-10-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This prepares the removal of the big kernel lock from the file locking code. We still use the BKL as long as fs/lockd uses it and ceph might sleep, but we can flip the definition to a private spinlock as soon as that's done. All users outside of fs/lockd get converted to use lock_flocks() instead of lock_kernel() where appropriate. Based on an earlier patch to use a spinlock from Matthew Wilcox, who has attempted this a few times before, the earliest patch from over 10 years ago turned it into a semaphore, which ended up being slower than the BKL and was subsequently reverted. Someone should do some serious performance testing when this becomes a spinlock, since this has caused problems before. Using a spinlock should be at least as good as the BKL in theory, but who knows... Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Matthew Wilcox <willy@linux.intel.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Miklos Szeredi <mszeredi@suse.cz> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: John Kacur <jkacur@redhat.com> Cc: Sage Weil <sage@newdream.net> Cc: linux-kernel@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org
* Merge branch 'for-next' into for-linusJiri Kosina2010-03-08
|\ | | | | | | | | | | | | | | | | Conflicts: Documentation/filesystems/proc.txt arch/arm/mach-u300/include/mach/debug-macro.S drivers/net/qlge/qlge_ethtool.c drivers/net/qlge/qlge_main.c drivers/net/typhoon.c
| * Fix misspelling of "should" and "shouldn't" in comments.Adam Buchbinder2010-02-05
| | | | | | | | | | | | | | Some comments misspell "should" or "shouldn't"; this fixes them. No code changes. Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* | Switch may_open() and break_lease() to passing O_...Al Viro2010-03-03
|/ | | | | | ... instead of mixing FMODE_ and O_ Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* const: make lock_manager_operations constAlexey Dobriyan2009-09-22
| | | | | | Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'sched-core-for-linus' of ↵Linus Torvalds2009-09-11
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (64 commits) sched: Fix sched::sched_stat_wait tracepoint field sched: Disable NEW_FAIR_SLEEPERS for now sched: Keep kthreads at default priority sched: Re-tune the scheduler latency defaults to decrease worst-case latencies sched: Turn off child_runs_first sched: Ensure that a child can't gain time over it's parent after fork() sched: enable SD_WAKE_IDLE sched: Deal with low-load in wake_affine() sched: Remove short cut from select_task_rq_fair() sched: Turn on SD_BALANCE_NEWIDLE sched: Clean up topology.h sched: Fix dynamic power-balancing crash sched: Remove reciprocal for cpu_power sched: Try to deal with low capacity, fix update_sd_power_savings_stats() sched: Try to deal with low capacity sched: Scale down cpu_power due to RT tasks sched: Implement dynamic cpu_power sched: Add smt_gain sched: Update the cpu_power sum during load-balance sched: Add SD_PREFER_SIBLING ...
| * sched: Convert the only user of cond_resched_bkl to use cond_resched()Frederic Weisbecker2009-07-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | fs/locks.c:flock_lock_file() is the only user of cond_resched_bkl() This helper doesn't do anything more than cond_resched(). The latter naming is enough to explain that we are rescheduling if needed. The bkl suffix suggests another semantics but it's actually a synonym of cond_resched(). Reported-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1247725694-6082-7-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | security: fix security_file_lock cmd argumentSten Spans2009-07-16
|/ | | | | | | | Pass posix-translated lock operations to security_file_lock when invoked via sys_flock. Signed-off-by: Sten Spans <Sten_Spans@genua.de> Signed-off-by: James Morris <jmorris@namei.org>
* lockd: call locks_release_private to cleanup per-filesystem stateFelix Blyakher2009-04-24
| | | | | | | | | | | | | | | | For every lock request lockd creates a new file_lock object in nlmsvc_setgrantargs() by copying the passed in file_lock with locks_copy_lock(). A filesystem can attach it's own lock_operations vector to the file_lock. It has to be cleaned up at the end of the file_lock's life. However, lockd doesn't do it today, yet it asserts in nlmclnt_release_lockargs() that the per-filesystem state is clean. This patch fixes it by exporting locks_release_private() and adding it to nlmsvc_freegrantargs(), to be symmetrical to creating a file_lock in nlmsvc_setgrantargs(). Signed-off-by: Felix Blyakher <felixb@sgi.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* [CVE-2009-0029] System call wrappers part 16Heiko Carstens2009-01-14
| | | | Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
* CRED: Wrap task credential accesses in the filesystem subsystemDavid Howells2008-11-13
| | | | | | | | | | | | | | | | | Wrap access to task credentials so that they can be separated more easily from the task_struct during the introduction of COW creds. Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id(). Change some task->e?[ug]id to task_e?[ug]id(). In some places it makes more sense to use RCU directly rather than a convenient wrapper; these will be addressed by later patches. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: James Morris <jmorris@namei.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: James Morris <jmorris@namei.org>
* Merge branch 'proc' of ↵Linus Torvalds2008-10-23
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/adobriyan/proc * 'proc' of git://git.kernel.org/pub/scm/linux/kernel/git/adobriyan/proc: (35 commits) proc: remove fs/proc/proc_misc.c proc: move /proc/vmcore creation to fs/proc/vmcore.c proc: move pagecount stuff to fs/proc/page.c proc: move all /proc/kcore stuff to fs/proc/kcore.c proc: move /proc/schedstat boilerplate to kernel/sched_stats.h proc: move /proc/modules boilerplate to kernel/module.c proc: move /proc/diskstats boilerplate to block/genhd.c proc: move /proc/zoneinfo boilerplate to mm/vmstat.c proc: move /proc/vmstat boilerplate to mm/vmstat.c proc: move /proc/pagetypeinfo boilerplate to mm/vmstat.c proc: move /proc/buddyinfo boilerplate to mm/vmstat.c proc: move /proc/vmallocinfo to mm/vmalloc.c proc: move /proc/slabinfo boilerplate to mm/slub.c, mm/slab.c proc: move /proc/slab_allocators boilerplate to mm/slab.c proc: move /proc/interrupts boilerplate code to fs/proc/interrupts.c proc: move /proc/stat to fs/proc/stat.c proc: move rest of /proc/partitions code to block/genhd.c proc: move /proc/cpuinfo code to fs/proc/cpuinfo.c proc: move /proc/devices code to fs/proc/devices.c proc: move rest of /proc/locks to fs/locks.c ...
| * proc: move rest of /proc/locks to fs/locks.cAlexey Dobriyan2008-10-23
| | | | | | | | Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
* | [PATCH] introduce fmode_t, do annotationsAl Viro2008-10-21
|/ | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* SL*B: drop kmem cache argument from constructorAlexey Dobriyan2008-07-26
| | | | | | | | | | | | | | | | | | | | | | | | Kmem cache passed to constructor is only needed for constructors that are themselves multiplexeres. Nobody uses this "feature", nor does anybody uses passed kmem cache in non-trivial way, so pass only pointer to object. Non-trivial places are: arch/powerpc/mm/init_64.c arch/powerpc/mm/hugetlbpage.c This is flag day, yes. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Acked-by: Christoph Lameter <cl@linux-foundation.org> Cc: Jon Tollefson <kniht@linux.vnet.ibm.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Matt Mackall <mpm@selenic.com> [akpm@linux-foundation.org: fix arch/powerpc/mm/hugetlbpage.c] [akpm@linux-foundation.org: fix mm/slab.c] [akpm@linux-foundation.org: fix ubifs] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* locks: allow ->lock() to return FILE_LOCK_DEFERREDMiklos Szeredi2008-07-25
| | | | | | | | | | | | | | | | | | Allow filesystem's ->lock() method to call posix_lock_file() instead of posix_lock_file_wait(), and return FILE_LOCK_DEFERRED. This makes it possible to implement a such a ->lock() function, that works with the lock manager, which needs the call to be asynchronous. Now the vfs_lock_file() helper can be used, so this is a cleanup as well. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: Matthew Wilcox <matthew@wil.cx> Cc: David Teigland <teigland@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* locks: cleanup code duplicationMiklos Szeredi2008-07-25
| | | | | | | | | | | | | Extract common code into a function. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: Matthew Wilcox <matthew@wil.cx> Cc: David Teigland <teigland@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* locks: add special return value for asynchronous locksMiklos Szeredi2008-07-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use a special error value FILE_LOCK_DEFERRED to mean that a locking operation returned asynchronously. This is returned by posix_lock_file() for sleeping locks to mean that the lock has been queued on the block list, and will be woken up when it might become available and needs to be retried (either fl_lmops->fl_notify() is called or fl_wait is woken up). f_op->lock() to mean either the above, or that the filesystem will call back with fl_lmops->fl_grant() when the result of the locking operation is known. The filesystem can do this for sleeping as well as non-sleeping locks. This is to make sure, that return values of -EAGAIN and -EINPROGRESS by filesystems are not mistaken to mean an asynchronous locking. This also makes error handling in fs/locks.c and lockd/svclock.c slightly cleaner. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: Matthew Wilcox <matthew@wil.cx> Cc: David Teigland <teigland@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [patch 4/4] flock: remove unused fields from file_lock_operationsDenis V. Lunev2008-06-23
| | | | | | | | | | | fl_insert and fl_remove are not used right now in the kernel. Remove them. Signed-off-by: Denis V. Lunev <den@openvz.org> Cc: Matthew Wilcox <matthew@wil.cx> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: "J. Bruce Fields" <bfields@fieldses.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Add new 'cond_resched_bkl()' helper functionLinus Torvalds2008-05-11
| | | | | | | | | | | | | | | | | | It acts exactly like a regular 'cond_resched()', but will not get optimized away when CONFIG_PREEMPT is set. Normal kernel code is already preemptable in the presense of CONFIG_PREEMPT, so cond_resched() is optimized away (see commit 02b67cc3ba36bdba351d6c3a00593f4ec550d9d3 "sched: do not do cond_resched() when CONFIG_PREEMPT"). But when wanting to conditionally reschedule while holding a lock, you need to use "cond_sched_lock(lock)", and the new function is the BKL equivalent of that. Also make fs/locks.c use it. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] fix SMP ordering hole in fcntl_setlk()Al Viro2008-05-06
| | | | | | | | | | | | | | | | | | | | | | fcntl_setlk()/close() race prevention has a subtle hole - we need to make sure that if we *do* have an fcntl/close race on SMP box, the access to descriptor table and inode->i_flock won't get reordered. As it is, we get STORE inode->i_flock, LOAD descriptor table entry vs. STORE descriptor table entry, LOAD inode->i_flock with not a single lock in common on both sides. We do have BKL around the first STORE, but check in locks_remove_posix() is outside of BKL and for a good reason - we don't want BKL on common path of close(2). Solution is to hold ->file_lock around fcheck() in there; that orders us wrt removal from descriptor table that preceded locks_remove_posix() on close path and we either come first (in which case eviction will be handled by the close side) or we'll see the effect of close and do eviction ourselves. Note that even though it's read-only access, we do need ->file_lock here - rcu_read_lock() won't be enough to order the things. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* [PATCH] split linux/file.hAl Viro2008-05-01
| | | | | | Initial splitoff of the low-level stuff; taken to fdtable.h Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Export __locks_copy_lock() so modular lockd buildsRoland Dreier2008-04-25
| | | | | | | | | | | | | | | | | Commit 1a747ee0 ("locks: don't call ->copy_lock methods on return of conflicting locks") changed fs/lockd/svclock.c to call __locks_copy_lock() instead of locks_copy_lock(), but lockd can be built as a module and __locks_copy_lock() is not exported, which causes a build error ERROR: "__locks_copy_lock" [fs/lockd/lockd.ko] undefined! with CONFIG_LOCKD=m. Fix this by exporting __locks_copy_lock(). Signed-off-by: Roland Dreier <rolandd@cisco.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* locks: don't call ->copy_lock methods on return of conflicting locksJ. Bruce Fields2008-04-25
| | | | | | | | | | | | | | | | The file_lock structure is used both as a heavy-weight representation of an active lock, with pointers to reference-counted structures, etc., and as a simple container for parameters that describe a file lock. The conflicting lock returned from __posix_lock_file is an example of the latter; so don't call the filesystem or lock manager callbacks when copying to it. This also saves the need for an unnecessary locks_init_lock in the nfsv4 server. Thanks to Trond for pointing out the error. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
* leases: remove unneeded variable from fcntl_setlease().David M. Richter2008-04-25
| | | | | | | | fcntl_setlease() has a struct dentry* that is used only once; this patch removes it. Signed-off-by: David M. Richter <richterd@citi.umich.edu> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* leases: move lock allocation earlier in generic_setlease()David M. Richter2008-04-25
| | | | | | | | | | | In generic_setlease(), the struct file_lock is allocated after tests for the presence of conflicting readers/writers is done, despite the fact that the allocation might block; this patch moves the allocation earlier. A subsequent set of patches will rely on this behavior to properly serialize between a modified __break_lease() and generic_setlease(). Signed-off-by: David M. Richter <richterd@citi.umich.edu> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* leases: when unlocking, skip locking-related stepsDavid M. Richter2008-04-25
| | | | | | | | In generic_setlease(), we don't need to allocate a new struct file_lock or check for readers or writers when called with F_UNLCK. Signed-off-by: David M. Richter <richterd@citi.umich.edu> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* leases: fix a return-value mixupDavid M. Richter2008-04-25
| | | | | | | | | Fixes a return-value mixup from 85c59580b30c82aa771aa33b37217a6b6851bc14 "locks: Fix potential OOPS in generic_setlease()", in which -ENOMEM replaced what had been intended to stay -EAGAIN in the variable "error". Signed-off-by: David M. Richter <richterd@citi.umich.edu> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* fs: Remove unnecessary inclusions of asm/semaphore.hMatthew Wilcox2008-04-18
| | | | | | | None of these files use any of the functionality promised by asm/semaphore.h. Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
* locks: fix possible infinite loop in fcntl(F_SETLKW) over nfsJ. Bruce Fields2008-04-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Miklos Szeredi found the bug: "Basically what happens is that on the server nlm_fopen() calls nfsd_open() which returns -EACCES, to which nlm_fopen() returns NLM_LCK_DENIED. "On the client this will turn into a -EAGAIN (nlm_stat_to_errno()), which in will cause fcntl_setlk() to retry forever." So, for example, opening a file on an nfs filesystem, changing permissions to forbid further access, then trying to lock the file, could result in an infinite loop. And Trond Myklebust identified the culprit, from Marc Eshel and I: 7723ec9777d9832849b76475b1a21a2872a40d20 "locks: factor out generic/filesystem switch from setlock code" That commit claimed to just be reshuffling code, but actually introduced a behavioral change by calling the lock method repeatedly as long as it returned -EAGAIN. We assumed this would be safe, since we assumed a lock of type SETLKW would only return with either success or an error other than -EAGAIN. However, nfs does can in fact return -EAGAIN in this situation, and independently of whether that behavior is correct or not, we don't actually need this change, and it seems far safer not to depend on such assumptions about the filesystem's ->lock method. Therefore, revert the problematic part of the original commit. This leaves vfs_lock_file() and its other callers unchanged, while returning fcntl_setlk and fcntl_setlk64 to their former behavior. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Tested-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: Marc Eshel <eshel@almaden.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>