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path: root/fs/lockd/mon.c
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2013-02-05sunrpc: move address copy/cmp/convert routines and prototypes from clnt.h to ↵Jeff Layton
addr.h These routines are used by server and client code, so having them in a separate header would be best. Signed-off-by: Jeff Layton <jlayton@redhat.com> Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-11-04lockd: Remove trivial BUG_ON()s from the NSM codeTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-10-24LOCKD: Clear ln->nsm_clnt only when ln->nsm_users is zeroTrond Myklebust
The current code is clearing it in all cases _except_ when zero. Reported-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: stable@vger.kernel.org
2012-10-24LOCKD: fix races in nsm_client_getTrond Myklebust
Commit e9406db20fecbfcab646bad157b4cfdc7cadddfb (lockd: per-net NSM client creation and destruction helpers introduced) contains a nasty race on initialisation of the per-net NSM client because it doesn't check whether or not the client is set after grabbing the nsm_create_mutex. Reported-by: Nix <nix@esperi.org.uk> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: stable@vger.kernel.org
2012-10-01lockd: create and use per-net NSM RPC clients on MON/UNMON requestsStanislav Kinsbursky
NSM RPC client can be required on NFSv3 umount, when child reaper is dying (and destroying it's mount namespace). It means, that current nsproxy is set to NULL already, but creation of RPC client requires UTS namespace for gaining hostname string. This patch creates reference-counted per-net NSM client on first monitor request and destroys it after last unmonitor request. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Cc: <stable@vger.kernel.org> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-10-01lockd: use rpc client's cl_nodename for id encodingStanislav Kinsbursky
Taking hostname from uts namespace if not safe, because this cuold be performind during umount operation on child reaper death. And in this case current->nsproxy is NULL already. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Cc: <stable@vger.kernel.org> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-10-01lockd: per-net NSM client creation and destruction helpers introducedStanislav Kinsbursky
NSM RPC client can be required on NFSv3 umount, when child reaper is dying (and destroying it's mount namespace). It means, that current nsproxy is set to NULL already, but creation of RPC client requires UTS namespace for gaining hostname string. This patch introduces reference counted NFS RPC clients creation and destruction helpers (similar to RPCBIND RPC clients). Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Cc: <stable@vger.kernel.org> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-02-15LockD: make NSM network namespace awareStanislav Kinsbursky
NLM host is network namespace aware now. So NSM have to take it into account. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-02-01SUNRPC: constify the rpc_programTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-12module_param: make bool parameters really bool (drivers & misc)Rusty Russell
module_param(bool) used to counter-intuitively take an int. In fddd5201 (mid-2009) we allowed bool or int/unsigned int using a messy trick. It's time to remove the int/unsigned int option. For this version it'll simply give a warning, but it'll break next kernel version. Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-12-16SUNRPC: New xdr_streams XDR decoder APIChuck Lever
Now that all client-side XDR decoder routines use xdr_streams, there should be no need to support the legacy calling sequence [rpc_rqst *, __be32 *, RPC res *] anywhere. We can construct an xdr_stream in the generic RPC code, instead of in each decoder function. This is a refactoring change. It should not cause different behavior. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-12-16SUNRPC: New xdr_streams XDR encoder APIChuck Lever
Now that all client-side XDR encoder routines use xdr_streams, there should be no need to support the legacy calling sequence [rpc_rqst *, __be32 *, RPC arg *] anywhere. We can construct an xdr_stream in the generic RPC code, instead of in each encoder function. Also, all the client-side encoder functions return 0 now, making a return value superfluous. Take this opportunity to convert them to return void instead. This is a refactoring change. It should not cause different behavior. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-12-16NSM: Avoid return code checking in NSM XDR encoder functionsChuck Lever
Clean up. The trend in the other XDR encoder functions is to BUG() when encoding problems occur, since a problem here is always due to a local coding error. Then, instead of a status, zero is unconditionally returned. Update the NSM XDR encoders to behave this way. To finish the update, use the new-style be32_to_cpup() and cpu_to_be32() macros, and compute the buffer sizes using raw integers instead of sizeof(). This matches the conventions used in other XDR functions Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-10-01sunrpc: Add net to rpc_create_argsPavel Emelyanov
Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h 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>
2010-02-08lockd: don't clear sm_monitored on nsm_reboot_lookupJeff Layton
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>
2009-08-21sunrpc: add routine for comparing addressesJeff Layton
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>
2009-08-09lockd: Replace nsm_display_address() with rpc_ntop()Chuck Lever
Clean up. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-06-18lockd: Don't bother with RPC ping for NSM upcallsChuck Lever
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>
2009-06-18lockd: Update NSM state from SM_MON repliesChuck Lever
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>
2009-04-01NSM: Fix unaligned accesses in nsm_init_private()Mans Rullgard
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>
2009-01-06NSM: Move nsm_create()Chuck Lever
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>
2009-01-06NSM: Move nsm_use_hostnames to mon.cChuck Lever
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>
2009-01-06NSM: Move nsm_addr() to fs/lockd/mon.cChuck Lever
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>
2009-01-06NSM: Remove include/linux/lockd/sm_inter.hChuck Lever
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>
2009-01-06NSM: Replace IP address as our nlm_reboot lookup keyChuck Lever
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>
2009-01-06NSM: More clean up of nsm_get_handle()Chuck Lever
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>
2009-01-06NSM: Refactor nsm_handle creation into a helper functionChuck Lever
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>
2009-01-06NLM: Remove "create" argument from nsm_find()Chuck Lever
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>
2009-01-06NSM: Add nsm_lookup() functionChuck Lever
Introduce a new API to fs/lockd/mon.c that allows nlm_host_rebooted() to lookup up nsm_handles via the contents of an nlm_reboot struct. The new function is equivalent to calling nsm_find() with @create set to zero, but it takes a struct nlm_reboot instead of separate arguments. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NSM: Encode the new "priv" cookie for NSMPROC_MON requestsChuck Lever
Pass the new "priv" cookie to NSMPROC_MON's XDR encoder, instead of creating the "priv" argument in the encoder at call time. This patch should not cause a behavioral change: the contents of the cookie remain the same for the time being. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NSM: Generate NSMPROC_MON's "priv" argument when nsm_handle is createdChuck Lever
Introduce a new data type, used by both the in-kernel NLM and NSM implementations, that is used to manage the opaque "priv" argument for the NSMPROC_MON and NLMPROC_SM_NOTIFY calls. Construct the "priv" cookie when the nsm_handle is created. The nsm_init_private() function may look a little strange, but it is roughly equivalent to how the XDR encoder formed the "priv" argument. It's going to go away soon. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NSM: Remove !nsm check from nsm_release()Chuck Lever
The nsm_release() function should never be called with a NULL handle point. If it is, that's a bug. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NSM: Remove NULL pointer check from nsm_find()Chuck Lever
The nsm_find() function should never be called with a NULL IP address pointer. If it is, that's a bug. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NSM: Add dprintk() calls in nsm_find and nsm_releaseChuck Lever
Introduce some dprintk() calls in fs/lockd/mon.c that are enabled by the NLMDBG_MONITOR flag. These report when we find, create, and release nsm_handles. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NSM: Move nsm_find() to fs/lockd/mon.cChuck Lever
The nsm_find() function sets up fresh nsm_handle entries. This is where we will store the "priv" cookie used to lookup nsm_handles during reboot recovery. The cookie will be constructed when nsm_find() creates a new nsm_handle. As much as possible, I would like to keep everything that handles a "priv" cookie in fs/lockd/mon.c so that all the smarts are in one source file. That organization should make it pretty simple to see how all this works. To me, it makes more sense than the current arrangement to keep nsm_find() with nsm_monitor() and nsm_unmonitor(). So, start reorganizing by moving nsm_find() into fs/lockd/mon.c. The nsm_release() function comes along too, since it shares the nsm_lock global variable. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NSM: move to xdr_stream-based XDR encoders and decodersChuck Lever
Introduce xdr_stream-based XDR encoder and decoder functions, which are more careful about preventing RPC buffer overflows. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NSM: Move NSM program and procedure numbers to fs/lockd/mon.cChuck Lever
Clean up: Move the RPC program and procedure numbers for NSM into the one source file that needs them: fs/lockd/mon.c. And, as with NLM, NFS, and rpcbind calls, use NSMPROC_FOO instead of SM_FOO for NSM procedure numbers. Finally, make a couple of comments more precise: what is referred to here as SM_NOTIFY is really the NLM (lockd) NLMPROC_SM_NOTIFY downcall, not NSMPROC_NOTIFY. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NSM: Move NSM-related XDR data structures to lockd's xdr.hChuck Lever
Clean up: NSM's XDR data structures are used only in fs/lockd/mon.c, so move them there. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NSM: Check result of SM_UNMON upcallChuck Lever
Make sure any error returned by rpc.statd during an SM_UNMON call is reported rather than ignored completely. There isn't much to do with such an error, but we should log it in any case. Similar to a recent change to nsm_monitor(). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NLM: Move the public declaration of nsm_unmonitor() to lockd.hChuck Lever
Clean up. Make the nlm_host argument "const," and move the public declaration to lockd.h. Add a documenting comment. Bruce observed that nsm_unmonitor()'s only caller doesn't care about its return code, so make nsm_unmonitor() return void. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NSM: Release nsmhandle in nlm_destroy_hostChuck Lever
The nsm_handle's reference count is bumped in nlm_lookup_host(). It should be decremented in nlm_destroy_host() to make it easier to see the balance of these two operations. Move the nsm_release() call to fs/lockd/host.c. The h_nsmhandle pointer is set in nlm_lookup_host(), and never cleared. The nlm_destroy_host() function is never called for the same nlm_host twice, so h_nsmhandle won't ever be NULL when nsm_unmonitor() is called. All references to the nlm_host are gone before it is freed. We can skip making h_nsmhandle NULL just before the nlm_host is deallocated. It's also likely we can remove the h_nsmhandle NULL check in nlmsvc_is_client() as well, but we can do that later when rearchitect- ing the nlm_host cache. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NLM: Move the public declaration of nsm_monitor() to lockd.hChuck Lever
Clean up. Make the nlm_host argument "const," and move the public declaration to lockd.h with other NSM public function (nsm_release, eg) and global variable declarations. Add a documenting comment. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NSM: Make sure to return an error if the SM_MON call result is not zeroChuck Lever
The nsm_monitor() function reports an error and does not set sm_monitored if the SM_MON upcall reply has a non-zero result code, but nsm_monitor() does not return an error to its caller in this case. Since sm_monitored is not set, the upcall is retried when the next NLM request invokes nsm_monitor(). However, that may not come for a while. In the meantime, at least one NLM request will potentially proceed without the peer being monitored properly. Have nsm_monitor() return an error if the result code is non-zero. This will cause all NLM requests to fail immediately if the upcall completed successfully but rpc.statd returned an error. This may be inconvenient in some cases (for example if rpc.statd cannot complete a proper DNS reverse lookup of the hostname), but will make the reboot monitoring service more robust by forcing such issues to be corrected by an admin. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NSM: Remove BUG_ON() in nsm_monitor()Chuck Lever
Clean up: Remove the BUG_ON() invocation in nsm_monitor(). It's not likely that nsm_monitor() is ever called with a NULL host pointer, and the code will die anyway if host is NULL. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NSM: Use sm_name instead of h_name in nsm_monitor() and nsm_unmonitor()Chuck Lever
Clean up: Use the sm_name field for reporting the hostname in nsm_monitor() and nsm_unmonitor(), just as the other functions in fs/lockd/mon.c do. The h_name field is just a copy of the sm_name pointer. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NSM: Support IPv6 version of mon_nameChuck Lever
The "mon_name" argument of the NSMPROC_MON and NSMPROC_UNMON upcalls is a string that contains the hostname or IP address of the remote peer to be notified when this host has rebooted. The sm-notify command uses this identifier to contact the peer when we reboot, so it must be either a well-qualified DNS hostname or a presentation format IP address string. When the "nsm_use_hostnames" sysctl is set to zero, the kernel's NSM provides a presentation format IP address in the "mon_name" argument. Otherwise, the "caller_name" argument from NLM requests is used, which is usually just the DNS hostname of the peer. To support IPv6 addresses for the mon_name argument, we use the nsm_handle's address eye-catcher, which already contains an appropriate presentation format address string. Using the eye-catcher string obviates the need to use a large buffer on the stack to form the presentation address string for the upcall. This patch also addresses a subtle bug. An NSMPROC_MON request and the subsequent NSMPROC_UNMON request for the same peer are required to use the same value for the "mon_name" argument. Otherwise, rpc.statd's NSMPROC_UNMON processing cannot locate the database entry for that peer and remove it. If the setting of nsm_use_hostnames is changed between the time the kernel sends an NSMPROC_MON request and the time it sends the NSMPROC_UNMON request for the same peer, the "mon_name" argument for these two requests may not be the same. This is because the value of "mon_name" is currently chosen at the moment the call is made based on the setting of nsm_use_hostnames To ensure both requests pass identical contents in the "mon_name" argument, we now select which string to use for the argument in the nsm_monitor() function. A pointer to this string is saved in the nsm_handle so it can be used for a subsequent NSMPROC_UNMON upcall. NB: There are other potential problems, such as how nlm_host_rebooted() might behave if nsm_use_hostnames were changed while hosts are still being monitored. This patch does not attempt to address those problems. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NSM: convert printk(KERN_DEBUG) to a dprintk()Chuck Lever
Clean up: make the printk(KERN_DEBUG) in nsm_mon_unmon() a dprintk, and add another dprintk to note if creating an RPC client for the upcall failed. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NSM: Use C99 structure initializer to initialize nsm_argsChuck Lever
Clean up: Use a C99 structure initializer instead of open-coding the initialization of nsm_args. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-10-31fs: replace NIPQUAD()Harvey Harrison
Using NIPQUAD() with NIPQUAD_FMT, %d.%d.%d.%d or %u.%u.%u.%u can be replaced with %pI4 Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>