From 27c438f53e79b81dc8805a81f6cd74824ba57290 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Mon, 2 Sep 2019 13:02:56 -0400 Subject: 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 Signed-off-by: Lance Shelton Signed-off-by: J. Bruce Fields --- fs/nfsd/nfssvc.c | 31 ++++++++++++++++++++++++++++++- 1 file changed, 30 insertions(+), 1 deletion(-) (limited to 'fs/nfsd/nfssvc.c') diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c index b944553c6927..3caaf5675259 100644 --- a/fs/nfsd/nfssvc.c +++ b/fs/nfsd/nfssvc.c @@ -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; } -- cgit v1.2.3