nlmsvc_notify_blocked walks the nlm_blocked list,
which requires nlm_blocked_lock.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
lockd should use lock_flocks() instead of lock_kernel()
to lock against posix locks accessing the i_flock list.
This is a prerequisite to turning lock_flocks into a
spinlock.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: J. Bruce Fields <bfields@redhat.com>
* 'for-2.6.37' of git://linux-nfs.org/~bfields/linux: (99 commits)
svcrpc: svc_tcp_sendto XPT_DEAD check is redundant
svcrpc: no need for XPT_DEAD check in svc_xprt_enqueue
svcrpc: assume svc_delete_xprt() called only once
svcrpc: never clear XPT_BUSY on dead xprt
nfsd4: fix connection allocation in sequence()
nfsd4: only require krb5 principal for NFSv4.0 callbacks
nfsd4: move minorversion to client
nfsd4: delay session removal till free_client
nfsd4: separate callback change and callback probe
nfsd4: callback program number is per-session
nfsd4: track backchannel connections
nfsd4: confirm only on succesful create_session
nfsd4: make backchannel sequence number per-session
nfsd4: use client pointer to backchannel session
nfsd4: move callback setup into session init code
nfsd4: don't cache seq_misordered replies
SUNRPC: Properly initialize sock_xprt.srcaddr in all cases
SUNRPC: Use conventional switch statement when reclassifying sockets
sunrpc/xprtrdma: clean up workqueue usage
sunrpc: Turn list_for_each-s into the ..._entry-s
...
Fix up trivial conflicts (two different deprecation notices added in
separate branches) in Documentation/feature-removal-schedule.txt
This patch removes all but one call to lock_kernel() from the server.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This patch removes all calls to lock_kernel() from the client. This patch
should be applied after the "fs/lock.c prepare for BKL removal" patch submitted
by Arnd Bergmann on September 18.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
When lockd gets a notify downcall from statd, it'll search its hosts
cache and then clear the sm_monitored bit on the host it finds. The idea
is apparently to make lockd redo a SM_MON on the next lock request.
This is unnecessary and causes the kernel's NSM cache to go out of sync
with statd. statd doesn't stop monitoring a host when it gets a
SM_NOTIFY and there's no guarantee that another lock will occur after
the reclaim and before the unmount. In that event, no SM_UNMON will
occur.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
nsm_reboot_lookup takes a reference to the nsm_handle that it returns,
but nlm_host_rebooted never releases that reference.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up: Bruce observed we have more or less common logic in each of
svc_create_xprt()'s callers: the check to create an IPv6 RPC listener
socket only if CONFIG_IPV6 is set. I'm about to add another case
that does just the same.
If we move the ifdefs into __svc_xpo_create(), then svc_create_xprt()
call sites can get rid of the "#ifdef" ugliness, and can use the same
logic with or without IPv6 support available in the kernel.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* 'for-2.6.33' of git://linux-nfs.org/~bfields/linux: (42 commits)
nfsd: remove pointless paths in file headers
nfsd: move most of nfsfh.h to fs/nfsd
nfsd: remove unused field rq_reffh
nfsd: enable V4ROOT exports
nfsd: make V4ROOT exports read-only
nfsd: restrict filehandles accepted in V4ROOT case
nfsd: allow exports of symlinks
nfsd: filter readdir results in V4ROOT case
nfsd: filter lookup results in V4ROOT case
nfsd4: don't continue "under" mounts in V4ROOT case
nfsd: introduce export flag for v4 pseudoroot
nfsd: let "insecure" flag vary by pseudoflavor
nfsd: new interface to advertise export features
nfsd: Move private headers to source directory
vfs: nfsctl.c un-used nfsd #includes
lockd: Remove un-used nfsd headers #includes
s390: remove un-used nfsd #includes
sparc: remove un-used nfsd #includes
parsic: remove un-used nfsd #includes
compat.c: Remove dependence on nfsd private headers
...
In what history where these ever needed? Well not
any more.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
For consistency drop & in front of every proc_handler. Explicity
taking the address is unnecessary and it prevents optimizations
like stubbing the proc_handlers to NULL.
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Now that sys_sysctl is a generic wrapper around /proc/sys .ctl_name
and .strategy members of sysctl tables are dead code. Remove them.
Cc: Jan Harkes <jaharkes@cs.cmu.edu>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
* remove asm/atomic.h inclusion from linux/utsname.h --
not needed after kref conversion
* remove linux/utsname.h inclusion from files which do not need it
NOTE: it looks like fs/binfmt_elf.c do not need utsname.h, however
due to some personality stuff it _is_ needed -- cowardly leave ELF-related
headers and files alone.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-2.6.32' of git://linux-nfs.org/~bfields/linux: (68 commits)
nfsd4: nfsv4 clients should cross mountpoints
nfsd: revise 4.1 status documentation
sunrpc/cache: avoid variable over-loading in cache_defer_req
sunrpc/cache: use list_del_init for the list_head entries in cache_deferred_req
nfsd: return success for non-NFS4 nfs4_state_start
nfsd41: Refactor create_client()
nfsd41: modify nfsd4.1 backchannel to use new xprt class
nfsd41: Backchannel: Implement cb_recall over NFSv4.1
nfsd41: Backchannel: cb_sequence callback
nfsd41: Backchannel: Setup sequence information
nfsd41: Backchannel: Server backchannel RPC wait queue
nfsd41: Backchannel: Add sequence arguments to callback RPC arguments
nfsd41: Backchannel: callback infrastructure
nfsd4: use common rpc_cred for all callbacks
nfsd4: allow nfs4 state startup to fail
SUNRPC: Defer the auth_gss upcall when the RPC call is asynchronous
nfsd4: fix null dereference creating nfsv4 callback client
nfsd4: fix whitespace in NFSPROC4_CLNT_CB_NULL definition
nfsd41: sunrpc: add new xprt class for nfsv4.1 backchannel
sunrpc/cache: simplify cache_fresh_locked and cache_fresh_unlocked.
...
lockd needs these sort of routines, as does the NFSv4 callback code.
Move lockd's routines into common code and rename them so that they can
be used by others.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up: Use shared rpc_set_port() function instead of nlm_clear_port().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* 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>
* 'for-2.6.31' of git://fieldses.org/git/linux-nfsd: (60 commits)
SUNRPC: Fix the TCP server's send buffer accounting
nfsd41: Backchannel: minorversion support for the back channel
nfsd41: Backchannel: cleanup nfs4.0 callback encode routines
nfsd41: Remove ip address collision detection case
nfsd: optimise the starting of zero threads when none are running.
nfsd: don't take nfsd_mutex twice when setting number of threads.
nfsd41: sanity check client drc maxreqs
nfsd41: move channel attributes from nfsd4_session to a nfsd4_channel_attr struct
NFS: kill off complicated macro 'PROC'
sunrpc: potential memory leak in function rdma_read_xdr
nfsd: minor nfsd_vfs_write cleanup
nfsd: Pull write-gathering code out of nfsd_vfs_write
nfsd: track last inode only in use_wgather case
sunrpc: align cache_clean work's timer
nfsd: Use write gathering only with NFSv2
NFSv4: kill off complicated macro 'PROC'
NFSv4: do exact check about attribute specified
knfsd: remove unreported filehandle stats counters
knfsd: fix reply cache memory corruption
knfsd: reply cache cleanups
...
Cut NSM upcall RPC traffic in half -- don't do a NULL call first.
The cases where a ping would be helpful are rare.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
When rpc.statd starts up in user space at boot time, it attempts to
write the latest NSM local state number into
/proc/sys/fs/nfs/nsm_local_state.
If lockd.ko isn't loaded yet (as is the case in most configurations),
that file doesn't exist, thus the kernel's NSM state remains set to
its initial value of zero during lockd operation.
This is a problem because rpc.statd and lockd use the NSM state number
to prevent repeated lock recovery on rebooted hosts. If lockd sends
a zero NSM state, but then a delayed SM_NOTIFY with a real NSM state
number is received, there is no way for lockd or rpc.statd to
distinguish that stale SM_NOTIFY from an actual reboot. Thus lock
recovery could be performed after the rebooted host has already
started reclaiming locks, and those locks will be lost.
We could change /etc/init.d/nfslock so it always modprobes lockd.ko
before starting rpc.statd. However, if lockd.ko is ever unloaded
and reloaded, we are back at square one, since the NSM state is not
preserved across an unload/reload cycle. This may happen frequently
on clients that use automounter. A period of NFS inactivity causes
lockd.ko to be unloaded, and the kernel loses its NSM state setting.
Instead, let's use the fact that rpc.statd plants the local system's
NSM state in every SM_MON (and SM_UNMON) reply. lockd performs a
synchronous SM_MON upcall to the local rpc.statd _before_ sending its
first NLM request to a new remote. This would permit rpc.statd to
provide the current NSM state to lockd, even after lockd.ko had been
unloaded and reloaded.
Note that NLMPROC_LOCK arguments are constructed before the
nsm_monitor() call, so we have to rearrange argument construction very
slightly to make this all work out.
And, the kernel appears to treat NSM state as a u32 (see struct
nlm_args and nsm_res). Make nsm_local_state a u32 as well, to ensure
we don't get bogus comparison results.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If lockd is signalled soon enough after restart then locks_start_grace()
will try to re-add an entry to a list and trigger a lock corruption
warning.
Thanks to Wang Chen for the problem report and diagnosis.
WARNING: at lib/list_debug.c:26 __list_add+0x27/0x5c()
...
list_add corruption. next->prev should be prev (ef8fe958), but was ef8ff128. (next=ef8ff128).
...
Pid: 23062, comm: lockd Tainted: G W 2.6.30-rc2 #3
Call Trace:
[<c042d5b5>] warn_slowpath+0x71/0xa0
[<c0422a96>] ? update_curr+0x11d/0x125
[<c044b12d>] ? trace_hardirqs_on_caller+0x18/0x150
[<c044b270>] ? trace_hardirqs_on+0xb/0xd
[<c051c61a>] ? _raw_spin_lock+0x53/0xfa
[<c051c89f>] __list_add+0x27/0x5c
[<ef8f6daa>] locks_start_grace+0x22/0x30 [lockd]
[<ef8f34da>] set_grace_period+0x39/0x53 [lockd]
[<c06b8921>] ? lock_kernel+0x1c/0x28
[<ef8f3558>] lockd+0x64/0x164 [lockd]
[<c044b12d>] ? trace_hardirqs_on_caller+0x18/0x150
[<c04227b0>] ? complete+0x34/0x3e
[<ef8f34f4>] ? lockd+0x0/0x164 [lockd]
[<ef8f34f4>] ? lockd+0x0/0x164 [lockd]
[<c043dd42>] kthread+0x45/0x6b
[<c043dcfd>] ? kthread+0x0/0x6b
[<c0403c23>] kernel_thread_helper+0x7/0x10
Reported-by: Wang Chen <wangchen@cn.fujitsu.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: stable@kernel.org
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>
* 'for-2.6.30' of git://linux-nfs.org/~bfields/linux: (81 commits)
nfsd41: define nfsd4_set_statp as noop for !CONFIG_NFSD_V4
nfsd41: define NFSD_DRC_SIZE_SHIFT in set_max_drc
nfsd41: Documentation/filesystems/nfs41-server.txt
nfsd41: CREATE_EXCLUSIVE4_1
nfsd41: SUPPATTR_EXCLCREAT attribute
nfsd41: support for 3-word long attribute bitmask
nfsd: dynamically skip encoded fattr bitmap in _nfsd4_verify
nfsd41: pass writable attrs mask to nfsd4_decode_fattr
nfsd41: provide support for minor version 1 at rpc level
nfsd41: control nfsv4.1 svc via /proc/fs/nfsd/versions
nfsd41: add OPEN4_SHARE_ACCESS_WANT nfs4_stateid bmap
nfsd41: access_valid
nfsd41: clientid handling
nfsd41: check encode size for sessions maxresponse cached
nfsd41: stateid handling
nfsd: pass nfsd4_compound_state* to nfs4_preprocess_{state,seq}id_op
nfsd41: destroy_session operation
nfsd41: non-page DRC for solo sequence responses
nfsd41: Add a create session replay cache
nfsd41: create_session operation
...
This fixes unaligned accesses in nsm_init_private() when
creating nlm_reboot keys.
Signed-off-by: Mans Rullgard <mans@mansr.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Apparently a lot of people need to disable IPv6 completely on their
distributor-built systems, which have CONFIG_IPV6_MODULE enabled at
build time.
They do this by blacklisting the ipv6.ko module. This causes the
creation of the lockd service listener to fail if CONFIG_IPV6_MODULE
is set, but the module cannot be loaded.
Now that the kernel's PF_INET6 RPC listeners are completely separate
from PF_INET listeners, we can always start PF_INET. Then lockd can
try to start PF_INET6, but it isn't required to be available.
Note this has the added benefit that NLM callbacks from AF_INET6
servers will never come from AF_INET remotes. We no longer have to
worry about matching mapped IPv4 addresses to AF_INET when comparing
addresses.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We're about to convert over to using separate PF_INET and PF_INET6
listeners, instead of a single PF_INET6 listener that also receives
AF_INET requests and maps them to AF_INET6.
Clear the way by removing the logic in lockd and the NFSv4 callback
server that creates an AF_INET6 service listener.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Since an RPC service listener's protocol family is specified now via
svc_create_xprt(), it no longer needs to be passed to svc_create() or
svc_create_pooled(). Remove that argument from the synopsis of those
functions, and remove the sv_family field from the svc_serv struct.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The sv_family field is going away. Pass a protocol family argument to
svc_create_xprt() instead of extracting the family from the passed-in
svc_serv struct.
Again, as this is a listener socket and not an address, we make this
new argument an "int" protocol family, instead of an "sa_family_t."
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
No change in behavior, just rearranging the switch so that we break out
of the switch if and only if we're in the wait case.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
The NFS mount command may pass an AF_INET server address to lockd. If
lockd happens to be using a PF_INET6 listener, the nlm_cmp_addr() in
nlmclnt_grant() will fail to match requests from that host because they
will all have a mapped IPv4 AF_INET6 address.
Adopt the same solution used in nfs_sockaddr_match_ipaddr() for NFSv4
callbacks: if either address is AF_INET, map it to an AF_INET6 address
before doing the comparison.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If a client requests a blocking lock, is denied, then requests it again,
then here in nlmsvc_lock() we will call vfs_lock_file() without FL_SLEEP
set, because we've already queued a block and don't need the locks code
to do it again.
But that means vfs_lock_file() will return -EAGAIN instead of
FILE_LOCK_DENIED. So we still need to translate that -EAGAIN return
into a nlm_lck_blocked error in this case, and put ourselves back on
lockd's block list.
The bug was introduced by bde74e4bc6 "locks: add special return
value for asynchronous locks".
Thanks to Frank van Maarseveen for the report; his original test
case was essentially
for i in `seq 30`; do flock /nfsmount/foo sleep 10 & done
Tested-by: Frank van Maarseveen <frankvm@frankvm.com>
Reported-by: Frank van Maarseveen <frankvm@frankvm.com>
Cc: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up: Use Bruce's preferred control flow style in make_socks().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up: extract common logic in NLM's make_socks() function
into a helper.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
If the kernel is configured to support IPv6 and the RPC server can register
services via rpcbindv4, we are all set to enable IPv6 support for lockd.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Aime Le Rouzic <aime.le-rouzic@bull.net>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up: one last thing... relocate nsm_create() to eliminate the forward
declaration and group it near the only function that actually uses it.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up.
Treat the nsm_use_hostnames global variable like nsm_local_state.
Note that the default value of nsm_use_hostnames is still zero.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up: nsm_addr_in() is no longer used, and nsm_addr() is used only in
fs/lockd/mon.c, so move it there.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up: The include/linux/lockd/sm_inter.h header is nearly empty
now. Remove it.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
NLM provides file locking services for NFS files. Part of this service
includes a second protocol, known as NSM, which is a reboot
notification service. NLM uses this service to determine when to
reclaim locks or enter a grace period after a client or server reboots.
The NLM service (implemented by lockd in the Linux kernel) contacts
the local NSM service (implemented by rpc.statd in Linux user space)
via NSM protocol upcalls to register a callback when a particular
remote peer reboots.
To match the callback to the correct remote peer, the NLM service
constructs a cookie that it passes in the request. The NSM service
passes that cookie back to the NLM service when it is notified that
the given remote peer has indeed rebooted.
Currently on Linux, the cookie is the raw 32-bit IPv4 address of the
remote peer. To support IPv6 addresses, which are larger, we could
use all 16 bytes of the cookie to represent a full IPv6 address,
although we still can't represent an IPv6 address with a scope ID in
just 16 bytes.
Instead, to avoid the need for future changes to support additional
address types, we'll use a manufactured value for the cookie, and use
that to find the corresponding nsm_handle struct in the kernel during
the NLMPROC_SM_NOTIFY callback.
This should provide complete support in the kernel's NSM
implementation for IPv6 hosts, while remaining backwards compatible
with older rpc.statd implementations.
Note we also deal with another case where nsm_use_hostnames can change
while there are outstanding notifications, possibly resulting in the
loss of reboot notifications. After this patch, the priv cookie is
always used to lookup rebooted hosts in the kernel.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up: refactor nsm_get_handle() so it is organized the same way that
nsm_reboot_lookup() is.
There is an additional micro-optimization here. This change moves the
"hostname & nsm_use_hostnames" test out of the list_for_each_entry()
clause in nsm_get_handle(), since it is loop-invariant.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up. Refactor the creation of nsm_handles into a helper. Fields
are initialized in increasing address order to make efficient use of
CPU caches.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up: nsm_find() now has only one caller, and that caller
unconditionally sets the @create argument. Thus the @create
argument is no longer needed.
Since nsm_find() now has a more specific purpose, pick a more
appropriate name for it.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
