sunrpc: use seconds since boot in expiry cache

This protects us from confusion when the wallclock time changes.

We convert to and from wallclock when  setting or reading expiry
times.

Also use seconds since boot for last_clost time.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/fs/nfs/dns_resolve.c b/fs/nfs/dns_resolve.c
index dba50a5625db..a6e711ad130f 100644
--- a/fs/nfs/dns_resolve.c
+++ b/fs/nfs/dns_resolve.c
@@ -167,7 +167,7 @@ static int nfs_dns_show(struct seq_file *m, struct cache_detail *cd,
                 return 0;
         }
         item = container_of(h, struct nfs_dns_ent, h);
-        ttl = (long)item->h.expiry_time - (long)get_seconds();
+        ttl = item->h.expiry_time - seconds_since_boot();
         if (ttl < 0)
                 ttl = 0;
 
@@ -239,7 +239,7 @@ static int nfs_dns_parse(struct cache_detail *cd, char *buf, int buflen)
         ttl = get_expiry(&buf);
         if (ttl == 0)
                 goto out;
-        key.h.expiry_time = ttl + get_seconds();
+        key.h.expiry_time = ttl + seconds_since_boot();
 
         ret = -ENOMEM;
         item = nfs_dns_lookup(cd, &key);
@@ -301,7 +301,7 @@ static int do_cache_lookup_nowait(struct cache_detail *cd,
                 goto out_err;
         ret = -ETIMEDOUT;
         if (!test_bit(CACHE_VALID, &(*item)->h.flags)
-                        || (*item)->h.expiry_time < get_seconds()
+                        || (*item)->h.expiry_time < seconds_since_boot()
                         || cd->flush_time > (*item)->h.last_refresh)
                 goto out_put;
         ret = -ENOENT;