nfsd: Support the server resetting the boot verifier

Add support to allow the server to reset the boot verifier in order to
force clients to resend I/O after a timeout failure.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This commit is contained in:
Trond Myklebust 2019-09-02 13:02:56 -04:00 committed by J. Bruce Fields
parent 5e113224c1
commit 27c438f53e
5 changed files with 48 additions and 15 deletions

View File

@ -104,6 +104,7 @@ struct nfsd_net {
/* Time of server startup */
struct timespec64 nfssvc_boot;
seqlock_t boot_lock;
/*
* Max number of connections this nfsd container will allow. Defaults
@ -179,4 +180,7 @@ struct nfsd_net {
extern void nfsd_netns_free_versions(struct nfsd_net *nn);
extern unsigned int nfsd_net_id;
void nfsd_copy_boot_verifier(__be32 verf[2], struct nfsd_net *nn);
void nfsd_reset_boot_verifier(struct nfsd_net *nn);
#endif /* __NFSD_NETNS_H__ */

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@ -27,6 +27,7 @@ static u32 nfs3_ftypes[] = {
NF3SOCK, NF3BAD, NF3LNK, NF3BAD,
};
/*
* XDR functions for basic NFS types
*/
@ -751,14 +752,16 @@ nfs3svc_encode_writeres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_writeres *resp = rqstp->rq_resp;
struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
__be32 verf[2];
p = encode_wcc_data(rqstp, p, &resp->fh);
if (resp->status == 0) {
*p++ = htonl(resp->count);
*p++ = htonl(resp->committed);
/* unique identifier, y2038 overflow can be ignored */
*p++ = htonl((u32)nn->nfssvc_boot.tv_sec);
*p++ = htonl(nn->nfssvc_boot.tv_nsec);
nfsd_copy_boot_verifier(verf, nn);
*p++ = verf[0];
*p++ = verf[1];
}
return xdr_ressize_check(rqstp, p);
}
@ -1125,13 +1128,15 @@ nfs3svc_encode_commitres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_commitres *resp = rqstp->rq_resp;
struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
__be32 verf[2];
p = encode_wcc_data(rqstp, p, &resp->fh);
/* Write verifier */
if (resp->status == 0) {
/* unique identifier, y2038 overflow can be ignored */
*p++ = htonl((u32)nn->nfssvc_boot.tv_sec);
*p++ = htonl(nn->nfssvc_boot.tv_nsec);
nfsd_copy_boot_verifier(verf, nn);
*p++ = verf[0];
*p++ = verf[1];
}
return xdr_ressize_check(rqstp, p);
}

View File

@ -568,17 +568,11 @@ nfsd4_access(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
static void gen_boot_verifier(nfs4_verifier *verifier, struct net *net)
{
__be32 verf[2];
struct nfsd_net *nn = net_generic(net, nfsd_net_id);
__be32 *verf = (__be32 *)verifier->data;
/*
* This is opaque to client, so no need to byte-swap. Use
* __force to keep sparse happy. y2038 time_t overflow is
* irrelevant in this usage.
*/
verf[0] = (__force __be32)nn->nfssvc_boot.tv_sec;
verf[1] = (__force __be32)nn->nfssvc_boot.tv_nsec;
memcpy(verifier->data, verf, sizeof(verifier->data));
BUILD_BUG_ON(2*sizeof(*verf) != sizeof(verifier->data));
nfsd_copy_boot_verifier(verf, net_generic(net, nfsd_net_id));
}
static __be32

View File

@ -1477,6 +1477,7 @@ static __net_init int nfsd_init_net(struct net *net)
atomic_set(&nn->ntf_refcnt, 0);
init_waitqueue_head(&nn->ntf_wq);
seqlock_init(&nn->boot_lock);
mnt = vfs_kern_mount(&nfsd_fs_type, SB_KERNMOUNT, "nfsd", NULL);
if (IS_ERR(mnt)) {

View File

@ -344,6 +344,35 @@ static bool nfsd_needs_lockd(struct nfsd_net *nn)
return nfsd_vers(nn, 2, NFSD_TEST) || nfsd_vers(nn, 3, NFSD_TEST);
}
void nfsd_copy_boot_verifier(__be32 verf[2], struct nfsd_net *nn)
{
int seq = 0;
do {
read_seqbegin_or_lock(&nn->boot_lock, &seq);
/*
* This is opaque to client, so no need to byte-swap. Use
* __force to keep sparse happy. y2038 time_t overflow is
* irrelevant in this usage
*/
verf[0] = (__force __be32)nn->nfssvc_boot.tv_sec;
verf[1] = (__force __be32)nn->nfssvc_boot.tv_nsec;
} while (need_seqretry(&nn->boot_lock, seq));
done_seqretry(&nn->boot_lock, seq);
}
void nfsd_reset_boot_verifier_locked(struct nfsd_net *nn)
{
ktime_get_real_ts64(&nn->nfssvc_boot);
}
void nfsd_reset_boot_verifier(struct nfsd_net *nn)
{
write_seqlock(&nn->boot_lock);
nfsd_reset_boot_verifier_locked(nn);
write_sequnlock(&nn->boot_lock);
}
static int nfsd_startup_net(int nrservs, struct net *net, const struct cred *cred)
{
struct nfsd_net *nn = net_generic(net, nfsd_net_id);
@ -596,7 +625,7 @@ int nfsd_create_serv(struct net *net)
#endif
}
atomic_inc(&nn->ntf_refcnt);
ktime_get_real_ts64(&nn->nfssvc_boot); /* record boot time */
nfsd_reset_boot_verifier(nn);
return 0;
}