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path: root/fs/nfs/inode.c
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2009-09-24truncate: use new helpersnpiggin@suse.de
Update some fs code to make use of new helper functions introduced in the previous patch. Should be no significant change in behaviour (except CIFS now calls send_sig under i_lock, via inode_newsize_ok). Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Miklos Szeredi <miklos@szeredi.hu> Cc: linux-nfs@vger.kernel.org Cc: Trond.Myklebust@netapp.com Cc: linux-cifs-client@lists.samba.org Cc: sfrench@samba.org Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-08-19NFS: Add a dns resolver for use with NFSv4 referrals and migrationTrond Myklebust
The NFSv4 and NFSv4.1 protocols both allow for the redirection of a client from one server to another in order to support filesystem migration and replication. For full protocol support, we need to add the ability to convert a DNS host name into an IP address that we can feed to the RPC client. We'll reuse the sunrpc cache, now that it has been converted to work with rpc_pipefs. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-08-09NFSv4: Add 'server capability' flags for NFSv4 recommended attributesTrond Myklebust
If the NFSv4 server doesn't support a POSIX attribute, the generic NFS code needs to know that, so that it don't keep trying to poll for it. However, by the same count, if the NFSv4 server does support that attribute, then we should ensure that the inode metadata is appropriately labelled as being untrusted. For instance, if we don't know the correct value of the file's uid, we should certainly not be caching ACLs or ACCESS results. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-07-12headers: smp_lock.h reduxAlexey Dobriyan
* Remove smp_lock.h from files which don't need it (including some headers!) * Add smp_lock.h to files which do need it * Make smp_lock.h include conditional in hardirq.h It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT This will make hardirq.h inclusion cheaper for every PREEMPT=n config (which includes allmodconfig/allyesconfig, BTW) Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-03NFS: Use local disk inode cacheDavid Howells
Bind data storage objects in the local cache to NFS inodes. 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>
2009-04-03NFS: Register NFS for caching and retrieve the top-level indexDavid Howells
Register NFS for caching and retrieve the top-level cache index object cookie. 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>
2009-03-19NFS: Optimise NFS close()Trond Myklebust
Close-to-open cache consistency rules really only require us to flush out writes on calls to close(), and require us to revalidate attributes on the very last close of the file. Currently we appear to be doing a lot of extra attribute revalidation and cache flushes. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-03-11NFS: Throttle page dirtying while we're flushing to diskTrond Myklebust
The following patch is a combination of a patch by myself and Peter Staubach. Trond: If we allow other processes to dirty pages while a process is doing a consistency sync to disk, we can end up never making progress. Peter: Attached is a patch which addresses a continuing problem with the NFS client generating out of order WRITE requests. While this is compliant with all of the current protocol specifications, there are servers in the market which can not handle out of order WRITE requests very well. Also, this may lead to sub-optimal block allocations in the underlying file system on the server. This may cause the read throughputs to be reduced when reading the file from the server. Peter: There has been a lot of work recently done to address out of order issues on a systemic level. However, the NFS client is still susceptible to the problem. Out of order WRITE requests can occur when pdflush is in the middle of writing out pages while the process dirtying the pages calls generic_file_buffered_write which calls generic_perform_write which calls balance_dirty_pages_rate_limited which ends up calling writeback_inodes which ends up calling back into the NFS client to writes out dirty pages for the same file that pdflush happens to be working with. Signed-off-by: Peter Staubach <staubach@redhat.com> [modification by Trond to merge the two similar patches] Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-03-11NFS: cleanup - remove struct nfs_inode->ncommitTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-03-11NFSv4: Support NFSv4 optional attributes in the struct nfs_fattrTrond Myklebust
Currently, filling struct nfs_fattr is more or less an all or nothing operation, since NFSv2 and NFSv3 have only mandatory attributes. In NFSv4, some attributes are optional, and so we may simply not be able to fill in those fields. Furthermore, NFSv4 allows you to specify which attributes you are interested in retrieving, thus permitting you to optimise away retrieval of attributes that you know will no change... Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-03-11NFS: flush cached directory information slightly more readily.NeilBrown
If cached directory contents becomes incorrect, there is no way to flush the contents. This contrasts with files where file locking is the recommended way to ensure cache consistency between multiple applications (a read-lock always flushes the cache). Also while changes to files often change the size of the file (thus triggering a cache flush), changes to directories often do not change the apparent size (as the size is often rounded to a block size). So it is particularly important with directories to avoid the possibility of an incorrect cache wherever possible. When the link count on a directory changes it implies a change in the number of child directories, and so a change in the contents of this directory. So use that as a trigger to flush cached contents. When the ctime changes but the mtime does not, there are two possible reasons. 1/ The owner/mode information has been changed. 2/ utimes has been used to set the mtime backwards. In the first case, a data-cache flush is not required. In the second case it is. So on the basis that correctness trumps performance, flush the directory contents cache in this case also. Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-03-11NFS: Minor __nfs_revalidate_inode cleanupSuresh Jayaraman
Remove redundant NFS_STALE() check, a leftover due to the commit 691beb13cdc88358334ef0ba867c080a247a760f Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-12-23optimize attribute timeouts for "noac" and "actimeo=0"Peter Staubach
Hi. I've been looking at a bugzilla which describes a problem where a customer was advised to use either the "noac" or "actimeo=0" mount options to solve a consistency problem that they were seeing in the file attributes. It turned out that this solution did not work reliably for them because sometimes, the local attribute cache was believed to be valid and not timed out. (With an attribute cache timeout of 0, the cache should always appear to be timed out.) In looking at this situation, it appears to me that the problem is that the attribute cache timeout code has an off-by-one error in it. It is assuming that the cache is valid in the region, [read_cache_jiffies, read_cache_jiffies + attrtimeo]. The cache should be considered valid only in the region, [read_cache_jiffies, read_cache_jiffies + attrtimeo). With this change, the options, "noac" and "actimeo=0", work as originally expected. This problem was previously addressed by special casing the attrtimeo == 0 case. However, since the problem is only an off- by-one error, the cleaner solution is address the off-by-one error and thus, not require the special case. Thanx... ps Signed-off-by: Peter Staubach <staubach@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-12-23NFSv4: Convert the open and close ops to use fmodeTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-10-28NFS: Convert nfs_attr_generation_counter into an atomic_longTrond Myklebust
The most important property we need from nfs_attr_generation_counter is monotonicity, which is not guaranteed by the current system of smp memory barriers. We should convert it to an atomic_long_t, and drop the memory barriers. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-10-27Switch to a valid email address...Alan Cox
Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-14NFS: Fix a resolution problem with nfs_inode->cache_change_attributeTrond Myklebust
The cache_change_attribute is used to decide whether or not a directory has changed, in which case we may need to look it up again. Again, the use of 'jiffies' leads to an issue of resolution. Once again, the fix is to change nfs_inode->cache_change_attribute, and just make it a simple counter. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-10-14NFS: Fix the resolution problem with nfs_inode_attrs_need_update()Trond Myklebust
It appears that 'jiffies' timestamps do not have high enough resolution for nfs_inode_attrs_need_update(). One problem is that a GETATTR can be launched within < 1 jiffy of the last operation that updated the attribute. Another problem is that RPC calls can take < 1 jiffy to execute. We can fix this by switching the variables to use a simple global counter that gets incremented every time we start another GETATTR call. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-10-14NFS: Changes to inode->i_nlinks must set the NFS_INO_INVALID_ATTR flagTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-10-09NFS: Fix attribute updatesTrond Myklebust
This fixes a regression seen when running the Connectathon testsuite against an ext3 filesystem. The reason was that the inode was constantly being marked as 'just updated' by the jiffy wraparound test. This again meant that newer GETATTR calls were failing to pass the nfs_inode_attrs_need_update() test unless the changes caused a ctime update on the server, since they were perceived as having been started before the latest inode update. Given that nfs_inode_attrs_need_update() already checks for wraparound of nfsi->last_updated, we can drop the buggy "protection" in nfs_update_inode(). Also make a slight micro-optimisation of nfs_inode_attrs_need_update(): we are more often going to see time_after(fattr->time_start, nfsi->last_updated) be true, rather than seeing an update of ctime/size, so put that test first to ensure that we optimise away the ctime/size tests. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-10-07NFS: Allow concurrent inode revalidationTrond Myklebust
Currently, if two processes are both trying to revalidate metadata for the same inode, they will find themselves being serialised. There is no good justification for this now that we have improved our ability to detect stale attribute data, so we should remove that serialisation. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-10-07NFS: Fix up nfs_setattr_update_inode()Trond Myklebust
Ensure that it sets the inode metadata under the correct spinlock. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-10-07NFS: Don't clear nfsi->cache_validity in nfs_check_inode_attributes()Trond Myklebust
If we're merely checking the inode attributes because we suspect that the 'updated' attributes returned by the RPC call are stale, then we shouldn't be doing weak cache consistency updates or clearing the cache_validity flags. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-10-07NFS: Convert __nfs_revalidate_inode() to use nfs_refresh_inode()Trond Myklebust
In the case where there are parallel RPC calls to the same inode, we may receive stale metadata due to the lack of ordering, hence the sanity checking of metadata in nfs_refresh_inode(). Currently, __nfs_revalidate_inode() is calling nfs_update_inode() directly, without any further sanity checks, and hence may end up setting the inode up with stale metadata. Fix is to use nfs_refresh_inode() instead of nfs_update_inode(). Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-10-07NFS: Fix nfs_post_op_update_inode_force_wcc()Trond Myklebust
If we believe that the attributes are old (see nfs_refresh_inode()), then we shouldn't force an update. Also ensure that we hold the inode->i_lock across attribute checks and the call to nfs_refresh_inode_locked() to ensure that we don't race with other attribute updates. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-10-07NFS: Fix the NFS attribute updateTrond Myklebust
Currently nfs_refresh_inode() will only update the inode metadata if it sees that the RPC call that returned the nfs_fattr was started after the last update of the inode. This means that if we have parallel RPC calls to the same inode (when sending WRITE calls, for instance), we may often miss updates. This patch attempts to recover those missed updates by also accepting them if the ctime in the nfs_fattr is more recent than the inode's cached ctime. It also recovers the case where the file size has increased, but the ctime has not been updated due to limited ctime resolution. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-10-07NFS: Clean up nfs_refresh_inode() and nfs_post_op_update_inode()Trond Myklebust
Try to avoid taking and dropping the inode->i_lock more than once. Do so by moving the code in nfs_refresh_inode() that needs to be done under the spinlock into a function nfs_refresh_inode_locked(), and then having both nfs_refresh_inode() and nfs_post_op_update_inode() call it directly. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-26SL*B: drop kmem cache argument from constructorAlexey Dobriyan
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>
2008-07-15NFS: Remove attribute update related BKL referencesTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-15NFS: Remove BKL requirement from attribute updatesTrond Myklebust
The main problem is dealing with inode->i_size: we need to set the inode->i_lock on all attribute updates, and so vmtruncate won't cut it. Make an NFS-private version of vmtruncate that has the necessary locking semantics. The result should be that the following inode attribute updates are protected by inode->i_lock nfsi->cache_validity nfsi->read_cache_jiffies nfsi->attrtimeo nfsi->attrtimeo_timestamp nfsi->change_attr nfsi->last_updated nfsi->cache_change_attribute nfsi->access_cache nfsi->access_cache_entry_lru nfsi->access_cache_inode_lru nfsi->acl_access nfsi->acl_default nfsi->nfs_page_tree nfsi->ncommit nfsi->npages nfsi->open_files nfsi->silly_list nfsi->acl nfsi->open_states inode->i_size inode->i_atime inode->i_mtime inode->i_ctime inode->i_nlink inode->i_uid inode->i_gid The following is protected by dir->i_mutex nfsi->cookieverf Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09NFS: Ensure we zap only the access and acl caches when setting new aclsTrond Myklebust
...and ensure that we obey the NFS_INO_INVALID_ACL flag when retrieving the acls. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09NFS: Fix the ftruncate() credential problemTrond Myklebust
ftruncate() access checking is supposed to be performed at open() time, just like reads and writes. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-05-16nfs: path_{get,put}() cleanupsJan Blunck
Here are some more places where path_{get,put}() can be used instead of dput()/mntput() pair. Signed-off-by: Jan Blunck <jblunck@suse.de> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: "J. Bruce Fields" <bfields@fieldses.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-05-16nfs: replace remaining __FUNCTION__ occurrencesHarvey Harrison
__FUNCTION__ is gcc-specific, use __func__ Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: "J. Bruce Fields" <bfields@fieldses.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-05-16NFS: Ensure that 'noac' and/or 'actimeo=0' turn off attribute cachingTrond Myklebust
Both the 'noac' and 'actimeo=0' mount options should ensure that attributes are not cached, however a bug in nfs_attribute_timeout() means that currently, the attributes may in fact get cached for up to one jiffy. This has been seen to cause corruption in some applications. The reason for the bug is that the time_in_range() test returns 'true' as long as the current time lies between nfsi->read_cache_jiffies and nfsi->read_cache_jiffies + nfsi->attrtimeo. In other words, if jiffies equals nfsi->read_cache_jiffies, then we still cache the attribute data. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-04-24Merge branch 'devel'Trond Myklebust
2008-04-08NFS: initialize flags field in nfs_open_contextJeff Layton
The nfs_open_context struct had a "flags" field added recently, but the allocator isn't initializing it. It also looks like the allocator isn't initializing the mode or list either, but they seem to be overwritten by the caller, so that's less of an issue. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-03-14SUNRPC: Add a helper rpcauth_lookup_generic_cred()Trond Myklebust
The NFSv4 protocol allows clients to negotiate security protocols on the fly in the case where an administrator on the server changes the export settings and/or in the case where we may have a filesystem migration event. Instead of having the NFS client code cache credentials that are tied to a particular AUTH method it is therefore preferable to have a generic credential that can be converted into whatever AUTH is in use by the RPC client when the read/write/sillyrename/... is put on the wire. We do this by means of the new "generic" credential, which basically just caches the minimal information that is needed to look up an RPCSEC_GSS, AUTH_SYS, or AUTH_NULL credential. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-03-08Merge commit 'origin' into develTrond Myklebust
2008-03-07NFS: Fix the fsid revalidation in nfs_update_inode()Trond Myklebust
When we detect that we've crossed a mountpoint on the remote server, we must take care not to use that inode to revalidate the fsid on our current superblock. To do so, we label the inode as a remote mountpoint, and check for that in nfs_update_inode(). Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-25NFS: Add an nfsiod workqueueTrond Myklebust
NFS post-rpciod cleanups often involve tasks that cannot be safely performed within the rpciod context (due to deadlock concerns). We therefore add a dedicated NFS workqueue that can perform tasks like cleaning up state after an interrupted NFSv4 open() call, or calling put_nfs_open_context() after an asynchronous read or write call. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-25NFS: Fix a deadlock with lazy umountTrond Myklebust
We can't allow rpc callback functions like task->tk_ops->rpc_call_prepare() and task->tk_ops->rpc_call_done() to call mntput() in any way, since that will cause a deadlock when the call to rpc_shutdown_client() attempts to wait on 'task' to complete. We can avoid the above deadlock by moving calls to mntput to task->tk_ops->rpc_release() callback, since at that time the task will be marked as completed, and so rpc_shutdown_client won't attempt to wait on it. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-01Merge branch 'task_killable' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc * 'task_killable' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc: (22 commits) Remove commented-out code copied from NFS NFS: Switch from intr mount option to TASK_KILLABLE Add wait_for_completion_killable Add wait_event_killable Add schedule_timeout_killable Use mutex_lock_killable in vfs_readdir Add mutex_lock_killable Use lock_page_killable Add lock_page_killable Add fatal_signal_pending Add TASK_WAKEKILL exit: Use task_is_* signal: Use task_is_* sched: Use task_contributes_to_load, TASK_ALL and TASK_NORMAL ptrace: Use task_is_* power: Use task_is_* wait: Use TASK_NORMAL proc/base.c: Use task_is_* proc/array.c: Use TASK_REPORT perfmon: Use task_is_* ... Fixed up conflicts in NFS/sunrpc manually..
2008-01-30NFS: Add an asynchronous delegreturn operation for use in nfs_clear_inodeTrond Myklebust
Otherwise, there is a potential deadlock if the last dput() from an NFSv4 close() or other asynchronous operation leads to nfs_clear_inode calling the synchronous delegreturn. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30nfs: convert NFS_*(inode) helpers to static inlineBenny Halevy
Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30nfs: obliterate NFS_FLAGS macroBenny Halevy
use NFS_I(inode)->flags instead Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30NFS: define a function to update nfsi->cache_change_attributeTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30NFS: Prevent nfs_getattr() hang during heavy write workloadsChuck Lever
POSIX requires that ctime and mtime, as reported by the stat(2) call, reflect the activity of the most recent write(2). To that end, nfs_getattr() flushes pending dirty writes to a file before doing a GETATTR to allow the NFS server to set the file's size, ctime, and mtime properly. However, nfs_getattr() can be starved when a constant stream of application writes to a file prevents nfs_wb_nocommit() from completing. This usually results in hangs of programs doing a stat against an NFS file that is being written. "ls -l" is a common victim of this behavior. To prevent starvation, hold the file's i_mutex in nfs_getattr() to freeze applications writes temporarily so the client can more quickly obtain clean values for a file's size, mtime, and ctime. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30NFS: Ensure nfs_wcc_update_inode always converts file size to loff_tChuck Lever
The nfs_wcc_update_inode() function omits logic to convert the type of the NFS on-the-wire value of a file's size (__u64) to the type of file size value stored in struct inode (loff_t, which is signed). Everywhere else in the NFS client I checked already correctly converts the file size type. This effects only very large files. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-12-06NFS: Switch from intr mount option to TASK_KILLABLEMatthew Wilcox
By using the TASK_KILLABLE infrastructure, we can get rid of the 'intr' mount option. We have to use _killable everywhere instead of _interruptible as we get rid of rpc_clnt_sigmask/sigunmask. Signed-off-by: Liam R. Howlett <howlett@gmail.com> Signed-off-by: Matthew Wilcox <willy@linux.intel.com>