lwn.git/fs/lockd/mon.c, branch v3.0.15

SUNRPC: New xdr_streams XDR decoder API

2010-12-16T17:37:25+00:00

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 Tested-by: J. Bruce Fields Signed-off-by: Trond Myklebust

SUNRPC: New xdr_streams XDR encoder API

2010-12-16T17:37:25+00:00

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 Tested-by: J. Bruce Fields Signed-off-by: Trond Myklebust

NSM: Avoid return code checking in NSM XDR encoder functions

2010-12-16T17:37:24+00:00

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 Tested-by: J. Bruce Fields Signed-off-by: Trond Myklebust

sunrpc: Add net to rpc_create_args

2010-10-01T21:18:56+00:00

Signed-off-by: Pavel Emelyanov Signed-off-by: J. Bruce Fields

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

2010-03-30T13:02:32+00:00

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 Guess-its-ok-by: Christoph Lameter Cc: Ingo Molnar Cc: Lee Schermerhorn

lockd: don't clear sm_monitored on nsm_reboot_lookup

2010-02-08T21:20:35+00:00

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 Reviewed-by: Chuck Lever Signed-off-by: J. Bruce Fields

sunrpc: add routine for comparing addresses

2009-08-21T15:27:42+00:00

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 Acked-by: Chuck Lever Signed-off-by: J. Bruce Fields

lockd: Replace nsm_display_address() with rpc_ntop()

2009-08-09T19:09:39+00:00

Clean up. Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust

lockd: Don't bother with RPC ping for NSM upcalls

2009-06-18T01:02:11+00:00

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 Signed-off-by: Trond Myklebust

lockd: Update NSM state from SM_MON replies

2009-06-18T01:02:10+00:00

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 Signed-off-by: Trond Myklebust