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2008-02-04Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivialLinus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial: (79 commits) Jesper Juhl is the new trivial patches maintainer Documentation: mention email-clients.txt in SubmittingPatches fs/binfmt_elf.c: spello fix do_invalidatepage() comment typo fix Documentation/filesystems/porting fixes typo fixes in net/core/net_namespace.c typo fix in net/rfkill/rfkill.c typo fixes in net/sctp/sm_statefuns.c lib/: Spelling fixes kernel/: Spelling fixes include/scsi/: Spelling fixes include/linux/: Spelling fixes include/asm-m68knommu/: Spelling fixes include/asm-frv/: Spelling fixes fs/: Spelling fixes drivers/watchdog/: Spelling fixes drivers/video/: Spelling fixes drivers/ssb/: Spelling fixes drivers/serial/: Spelling fixes drivers/scsi/: Spelling fixes ...
2008-02-04Merge branch 'locks' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
* 'locks' of git://linux-nfs.org/~bfields/linux: pid-namespaces-vs-locks-interaction file locks: Use wait_event_interruptible_timeout() locks: clarify posix_locks_deadlock
2008-02-04vm audit: add VM_DONTEXPAND to mmap for drivers that need itNick Piggin
Drivers that register a ->fault handler, but do not range-check the offset argument, must set VM_DONTEXPAND in the vm_flags in order to prevent an expanding mremap from overflowing the resource. I've audited the tree and attempted to fix these problems (usually by adding VM_DONTEXPAND where it is not obvious). Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-03pid-namespaces-vs-locks-interactionVitaliy Gusev
fcntl(F_GETLK,..) can return pid of process for not current pid namespace (if process is belonged to the several namespaces). It is true also for pids in /proc/locks. So correct behavior is saving pointer to the struct pid of the process lock owner. Signed-off-by: Vitaliy Gusev <vgusev@openvz.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-03file locks: Use wait_event_interruptible_timeout()Matthew Wilcox
interruptible_sleep_on_locked() is just an open-coded wait_event_interruptible_timeout(), with the one difference that interruptible_sleep_on_locked() doesn't bother to check the condition on which it is waiting, depending instead on the BKL to avoid the case where it blocks after the wakeup has already been called. locks_block_on_timeout() is only used in one place, so it's actually simpler to inline it into its caller. Signed-off-by: Matthew Wilcox <willy@linux.intel.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-03locks: clarify posix_locks_deadlockJ. Bruce Fields
For such a short function (with such a long comment), posix_locks_deadlock() seems to cause a lot of confusion. Attempt to make it a bit clearer: - Remove the initial posix_same_owner() check, which can never pass (since this is only called in the case that block_fl and caller_fl conflict) - Use an explicit loop (and a helper function) instead of a goto. - Rewrite the comment, attempting a clearer explanation, and removing some uninteresting historical detail. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-03fs/binfmt_elf.c: spello fixOhad Ben-Cohen
s/litle/little Signed-off-by: Ohad Ben-Cohen <ohad@bencohen.org> Signed-off-by: Adrian Bunk <bunk@kernel.org>
2008-02-03fs/: Spelling fixesJoe Perches
Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Adrian Bunk <bunk@kernel.org>
2008-02-03Spelling fixes: lenght->lengthPaulius Zaleckas
Signed-off-by: Paulius Zaleckas <pauliusz@yahoo.com> Signed-off-by: Adrian Bunk <bunk@kernel.org>
2008-02-03Typoes: "whith" -> "with"Robert P. J. Day
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca> Signed-off-by: Adrian Bunk <bunk@kernel.org>
2008-02-03Fix a small number of "memeber" typoes.Robert P. J. Day
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca> Signed-off-by: Adrian Bunk <bunk@kernel.org>
2008-02-02Merge branch 'for-linus' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
* 'for-linus' of git://linux-nfs.org/~bfields/linux: (100 commits) SUNRPC: RPC program information is stored in unsigned integers SUNRPC: Move exported symbol definitions after function declaration part 2 NLM: tear down RPC clients in nlm_shutdown_hosts SUNRPC: spin svc_rqst initialization to its own function nfsd: more careful input validation in nfsctl write methods lockd: minor log message fix knfsd: don't bother mapping putrootfh enoent to eperm rdma: makefile rdma: ONCRPC RDMA protocol marshalling rdma: SVCRDMA sendto rdma: SVCRDMA recvfrom rdma: SVCRDMA Core Transport Services rdma: SVCRDMA Transport Module rdma: SVCRMDA Header File svc: Add svc_xprt_names service to replace svc_sock_names knfsd: Support adding transports by writing portlist file svc: Add svc API that queries for a transport instance svc: Add /proc/sys/sunrpc/transport files svc: Add transport hdr size for defer/revisit svc: Move the xprt independent code to the svc_xprt.c file ...
2008-02-01NLM: tear down RPC clients in nlm_shutdown_hostsJeff Layton
It's possible for a RPC to outlive the lockd daemon that created it, so we need to make sure that all RPC's are killed when lockd is coming down. When nlm_shutdown_hosts is called, kill off all RPC tasks associated with the host. Since we need to wait until they have all gone away, we might as well just shut down the RPC client altogether. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01nfsd: more careful input validation in nfsctl write methodsJ. Bruce Fields
Neil Brown points out that we're checking buf[size-1] in a couple places without first checking whether size is zero. Actually, given the implementation of simple_transaction_get(), buf[-1] is zero, so in both of these cases the subsequent check of the value of buf[size-1] will catch this case. But it seems fragile to depend on that, so add explicit checks for this case. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Acked-by: NeilBrown <neilb@suse.de>
2008-02-01lockd: minor log message fixJ. Bruce Fields
Wendy Cheng noticed that function name doesn't agree here. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Cc: Wendy Cheng <wcheng@redhat.com>
2008-02-01knfsd: don't bother mapping putrootfh enoent to epermJ. Bruce Fields
Neither EPERM and ENOENT map to valid errors for PUTROOTFH according to rfc 3530, and, if anything, ENOENT is likely to be slightly more informative; so don't bother mapping ENOENT to EPERM. (Probably this was originally done because one likely cause was that there is an fsid=0 export but that it isn't permitted to this particular client. Now that we allow WRONGSEC returns, this is somewhat less likely.) In the long term we should work to make this situation less likely, perhaps by turning off nfsv4 service entirely in the absence of the pseudofs root, or constructing a pseudofilesystem root ourselves in the kernel as necessary. Thanks to Benny Halevy <bhalevy@panasas.com> for pointing out this problem. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Cc: Benny Halevy <bhalevy@panasas.com>
2008-02-01svc: Add svc_xprt_names service to replace svc_sock_namesTom Tucker
Create a transport independent version of the svc_sock_names function. The toclose capability of the svc_sock_names service can be implemented using the svc_xprt_find and svc_xprt_close services. Signed-off-by: Tom Tucker <tom@opengridcomputing.com> Acked-by: Neil Brown <neilb@suse.de> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Greg Banks <gnb@sgi.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01knfsd: Support adding transports by writing portlist fileTom Tucker
Update the write handler for the portlist file to allow creating new listening endpoints on a transport. The general form of the string is: <transport_name><space><port number> For example: echo "tcp 2049" > /proc/fs/nfsd/portlist This is intended to support the creation of a listening endpoint for RDMA transports without adding #ifdef code to the nfssvc.c file. Transports can also be removed as follows: '-'<transport_name><space><port number> For example: echo "-tcp 2049" > /proc/fs/nfsd/portlist Attempting to add a listener with an invalid transport string results in EPROTONOSUPPORT and a perror string of "Protocol not supported". Attempting to remove an non-existent listener (.e.g. bad proto or port) results in ENOTCONN and a perror string of "Transport endpoint is not connected" Signed-off-by: Tom Tucker <tom@opengridcomputing.com> Acked-by: Neil Brown <neilb@suse.de> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Greg Banks <gnb@sgi.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01svc: Add svc API that queries for a transport instanceTom Tucker
Add a new svc function that allows a service to query whether a transport instance has already been created. This is used in lockd to determine whether or not a transport needs to be created when a lockd instance is brought up. Specifying 0 for the address family or port is effectively a wild-card, and will result in matching the first transport in the service's list that has a matching class name. Signed-off-by: Tom Tucker <tom@opengridcomputing.com> Acked-by: Neil Brown <neilb@suse.de> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Greg Banks <gnb@sgi.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01svc: Make close transport independentTom Tucker
Move sk_list and sk_ready to svc_xprt. This involves close because these lists are walked by svcs when closing all their transports. So I combined the moving of these lists to svc_xprt with making close transport independent. The svc_force_sock_close has been changed to svc_close_all and takes a list as an argument. This removes some svc internals knowledge from the svcs. This code races with module removal and transport addition. Thanks to Simon Holm Thøgersen for a compile fix. Signed-off-by: Tom Tucker <tom@opengridcomputing.com> Acked-by: Neil Brown <neilb@suse.de> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Greg Banks <gnb@sgi.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Cc: Simon Holm Thøgersen <odie@cs.aau.dk>
2008-02-01svc: Change services to use new svc_create_xprt serviceTom Tucker
Modify the various kernel RPC svcs to use the svc_create_xprt service. Signed-off-by: Tom Tucker <tom@opengridcomputing.com> Acked-by: Neil Brown <neilb@suse.de> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Greg Banks <gnb@sgi.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01Leak in nlmsvc_testlock for async GETFL caseOleg Drokin
Fix nlm_block leak for the case of supplied blocking lock info. Signed-off-by: Oleg Drokin <green@linuxhacker.ru> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01nfsd4: clean up access_valid, deny_valid checks.J. Bruce Fields
Document these checks a little better and inline, as suggested by Neil Brown (note both functions have two callers). Remove an obviously bogus check while we're there (checking whether unsigned value is negative). Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Cc: Neil Brown <neilb@suse.de>
2008-02-01nfsd: allow root to set uid and gid on createJ. Bruce Fields
The server silently ignores attempts to set the uid and gid on create. Based on the comment, this appears to have been done to prevent some overly-clever IRIX client from causing itself problems. Perhaps we should remove that hack completely. For now, at least, it makes sense to allow root (when no_root_squash is set) to set uid and gid. While we're there, since nfsd_create and nfsd_create_v3 share the same logic, pull that out into a separate function. And spell out the individual modifications of ia_valid instead of doing them both at once inside a conditional. Thanks to Roger Willcocks <roger@filmlight.ltd.uk> for the bug report and original patch on which this is based. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01lockd: fix a leak in nlmsvc_testlock asynchronous request handlingOleg Drokin
Without the patch, there is a leakage of nlmblock structure refcount that holds a reference nlmfile structure, that holds a reference to struct file, when async GETFL is used (-EINPROGRESS return from file_ops->lock()), and also in some error cases. Fix up a style nit while we're here. Signed-off-by: Oleg Drokin <green@linuxhacker.ru> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01nfsd: Allow AIX client to read dir containing mountpointsFrank Filz
This patch addresses a compatibility issue with a Linux NFS server and AIX NFS client. I have exported /export as fsid=0 with sec=krb5:krb5i I have mount --bind /home onto /export/home I have exported /export/home with sec=krb5i The AIX client mounts / -o sec=krb5:krb5i onto /mnt If I do an ls /mnt, the AIX client gets a permission error. Looking at the network traceIwe see a READDIR looking for attributes FATTR4_RDATTR_ERROR and FATTR4_MOUNTED_ON_FILEID. The response gives a NFS4ERR_WRONGSEC which the AIX client is not expecting. Since the AIX client is only asking for an attribute that is an attribute of the parent file system (pseudo root in my example), it seems reasonable that there should not be an error. In discussing this issue with Bruce Fields, I initially proposed ignoring the error in nfsd4_encode_dirent_fattr() if all that was being asked for was FATTR4_RDATTR_ERROR and FATTR4_MOUNTED_ON_FILEID, however, Bruce suggested that we avoid calling cross_mnt() if only these attributes are requested. The following patch implements bypassing cross_mnt() if only FATTR4_RDATTR_ERROR and FATTR4_MOUNTED_ON_FILEID are called. Since there is some complexity in the code in nfsd4_encode_fattr(), I didn't want to duplicate code (and introduce a maintenance nightmare), so I added a parameter to nfsd4_encode_fattr() that indicates whether it should ignore cross mounts and simply fill in the attribute using the passed in dentry as opposed to it's parent. Signed-off-by: Frank Filz <ffilzlnx@us.ibm.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01nfsd4: fix bad seqid on lock request incompatible with open modeJ. Bruce Fields
The failure to return a stateowner from nfs4_preprocess_seqid_op() means in the case where a lock request is of a type incompatible with an open (due to, e.g., an application attempting a write lock on a file open for read), means that fs/nfsd/nfs4xdr.c:ENCODE_SEQID_OP_TAIL() never bumps the seqid as it should. The client, attempting to close the file afterwards, then gets an (incorrect) bad sequence id error. Worse, this prevents the open file from ever being closed, so we leak state. Thanks to Benny Halevy and Trond Myklebust for analysis, and to Steven Wilton for the report and extensive data-gathering. Cc: Benny Halevy <bhalevy@panasas.com> Cc: Steven Wilton <steven.wilton@team.eftel.com.au> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01lockd: fix reference count leaks in async locking caseOleg Drokin
In a number of places where we wish only to translate nlm_drop_reply to rpc_drop_reply errors we instead return early with rpc_drop_reply, skipping some important end-of-function cleanup. This results in reference count leaks when lockd is doing posix locking on GFS2. Signed-off-by: Oleg Drokin <green@linuxhacker.ru> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01nfsd4: recognize callback channel failure earlierJ. Bruce Fields
When the callback channel fails, we inform the client of that by returning a cb_path_down error the next time it tries to renew its lease. If we wait most of a lease period before deciding that a callback has failed and that the callback channel is down, then we decrease the chances that the client will find out in time to do anything about it. So, mark the channel down as soon as we recognize that an rpc has failed. However, continue trying to recall delegations anyway, in hopes it will come back up. This will prevent more delegations from being given out, and ensure cb_path_down is returned to renew calls earlier, while still making the best effort to deliver recalls of existing delegations. Also fix a couple comments and remove a dprink that doesn't seem likely to be useful. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01nfsd4: miscellaneous nfs4state.c style fixesJ. Bruce Fields
Fix various minor style violations. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01nfsd4: make current_clientid localJ. Bruce Fields
Declare this variable in the one function where it's used, and clean up some minor style problems. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01nfsd: fix encode_entryplus_baggage() indentationJ. Bruce Fields
Fix bizarre indentation. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01nfsd4: kill unneeded cl_confirm checkJ. Bruce Fields
We generate a unique cl_confirm for every new client; so if we've already checked that this cl_confirm agrees with the cl_confirm of unconf, then we already know that it does not agree with the cl_confirm of conf. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01nfsd4: remove unnecessary cl_verifier check from setclientid_confirmJ. Bruce Fields
Again, the only way conf and unconf can have the same clientid is if they were created in the "probable callback update" case of setclientid, in which case we already know that the cl_verifier fields must agree. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01nfsd4: kill unnecessary same_name() in setclientid_confirmJ. Bruce Fields
If conf and unconf are both found in the lookup by cl_clientid, then they share the same cl_clientid. We always create a unique new cl_clientid field when creating a new client--the only exception is the "probable callback update" case in setclientid, where we copy the old cl_clientid from another clientid with the same name. Therefore two clients with the same cl_client field also always share the same cl_name field, and a couple of the checks here are redundant. Thanks to Simon Holm Thøgersen for a compile fix. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Cc: Simon Holm Thøgersen <odie@cs.aau.dk>
2008-02-01nfsd: uniquify cl_confirm valuesJ. Bruce Fields
Using a counter instead of the nanoseconds value seems more likely to produce a unique cl_confirm. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01nfsd: eliminate final bogus case from setclientid logicJ. Bruce Fields
We're supposed to generate a different cl_confirm verifier for each new client, so these to cl_confirm values should never be the same. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01nfsd4: kill some unneeded setclientid commentsJ. Bruce Fields
Most of these comments just summarize the code. The matching of code to the cases described in the RFC may still be useful, though; add specific section references to make that easier to follow. Also update references to the outdated RFC 3010. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01nfsd: minor fs/nfsd/auth.h cleanupJ. Bruce Fields
While we're here, let's remove the redundant (and now wrong) pathname in the comment, and the #ifdef __KERNEL__'s. Acked-by: NeilBrown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01nfsd: move nfsd/auth.h into fs/nfsdJ. Bruce Fields
This header is used only in a few places in fs/nfsd, so there seems to be little point to having it in include/. (Thanks to Robert Day for pointing this out.) Cc: Robert P. J. Day <rpjday@crashcourse.ca> Acked-by: NeilBrown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01knfsd: allow cache_register to return error on failureJ. Bruce Fields
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>
2008-02-01nfsd: fail init on /proc/fs/nfs/exports creation failureJ. Bruce Fields
I assume the reason failure of creation was ignored here was just to continue support embedded systems that want nfsd but not proc. However, in cases where proc is supported it would be clearer to fail entirely than to come up with some features disabled. Acked-by: NeilBrown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01nfsd: select CONFIG_PROC_FS in nfsv4 and gss server casesJ. Bruce Fields
The server depends on upcalls under /proc to support nfsv4 and gss. Acked-by: NeilBrown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01knfsd: cache unregistration needn't return errorJ. Bruce Fields
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>
2008-02-01nfsd: fail module init on reply cache init failureJ. Bruce Fields
If the reply cache initialization fails due to a kmalloc failure, currently we try to soldier on with a reduced (or nonexistant) reply cache. Better to just fail immediately: the failure is then much easier to understand and debug, and it could save us complexity in some later code. (But actually, it doesn't help currently because the cache is also turned off in some odd failure cases; we should probably find a better way to handle those failure cases some day.) Fix some minor style problems while we're at it, and rename nfsd_cache_init() to remove the need for a comment describing it. Acked-by: NeilBrown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01nfsd: cleanup nfsd module initialization cleanupJ. Bruce Fields
Handle the failure case here with something closer to the standard kernel style. Doesn't really matter for now, but I'd like to add a few more failure cases, and then this'll help. Acked-by: NeilBrown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01knfsd: cleanup nfsd4 properly on module init failureJ. Bruce Fields
We forgot to shut down the nfs4 state and idmapping code in this case. Acked-by: NeilBrown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01nfsd: Fix handling of negative lengths in read_buf()J. Bruce Fields
The length "nbytes" passed into read_buf should never be negative, but we check only for too-large values of "nbytes", not for too-small values. Make nbytes unsigned, so it's clear that the former tests are sufficient. (Despite this read_buf() currently correctly returns an xdr error in the case of a negative length, thanks to an unsigned comparison with size_of() and bounds-checking in kmalloc(). This seems very fragile, though.) Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01NFSD: Fix mixed sign comparison in nfs3svc_decode_symlinkargsChuck Lever
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Acked-By: NeilBrown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01NFSD: Use unsigned length argument for decode_pathnameChuck Lever
Clean up: path name lengths are unsigned on the wire, negative lengths are not meaningful natively either. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Acked-By: NeilBrown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>