linux-stable/fs/nfsd/lockd.c
Marc Eshel 9a8db97e77 knfsd: lockd: nfsd4: use same grace period for lockd and nfsd4
Both lockd and (in the nfsv4 case) nfsd enforce a "grace period" after reboot,
during which clients may reclaim locks from the previous server instance, but
may not acquire new locks.

Currently the lockd and nfsd enforce grace periods of different lengths.  This
may cause problems when we reboot a server with both v2/v3 and v4 clients.
For example, if the lockd grace period is shorter (as is likely the case),
then a v3 client might acquire a new lock that conflicts with a lock already
held (but not yet reclaimed) by a v4 client.

This patch calculates a lease time that lockd and nfsd can both use.

Signed-off-by: Marc Eshel <eshel@almaden.ibm.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-17 10:23:07 -07:00

82 lines
1.8 KiB
C

/*
* linux/fs/nfsd/lockd.c
*
* This file contains all the stubs needed when communicating with lockd.
* This level of indirection is necessary so we can run nfsd+lockd without
* requiring the nfs client to be compiled in/loaded, and vice versa.
*
* Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
*/
#include <linux/types.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/mount.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/svc.h>
#include <linux/nfsd/nfsd.h>
#include <linux/lockd/bind.h>
#define NFSDDBG_FACILITY NFSDDBG_LOCKD
/*
* Note: we hold the dentry use count while the file is open.
*/
static __be32
nlm_fopen(struct svc_rqst *rqstp, struct nfs_fh *f, struct file **filp)
{
__be32 nfserr;
struct svc_fh fh;
/* must initialize before using! but maxsize doesn't matter */
fh_init(&fh,0);
fh.fh_handle.fh_size = f->size;
memcpy((char*)&fh.fh_handle.fh_base, f->data, f->size);
fh.fh_export = NULL;
exp_readlock();
nfserr = nfsd_open(rqstp, &fh, S_IFREG, MAY_LOCK, filp);
fh_put(&fh);
rqstp->rq_client = NULL;
exp_readunlock();
/* We return nlm error codes as nlm doesn't know
* about nfsd, but nfsd does know about nlm..
*/
switch (nfserr) {
case nfs_ok:
return 0;
case nfserr_dropit:
return nlm_drop_reply;
#ifdef CONFIG_LOCKD_V4
case nfserr_stale:
return nlm4_stale_fh;
#endif
default:
return nlm_lck_denied;
}
}
static void
nlm_fclose(struct file *filp)
{
fput(filp);
}
static struct nlmsvc_binding nfsd_nlm_ops = {
.fopen = nlm_fopen, /* open file for locking */
.fclose = nlm_fclose, /* close file */
.get_grace_period = get_nfs4_grace_period,
};
void
nfsd_lockd_init(void)
{
dprintk("nfsd: initializing lockd\n");
nlmsvc_ops = &nfsd_nlm_ops;
}
void
nfsd_lockd_shutdown(void)
{
nlmsvc_ops = NULL;
}