4 files changed, 48 insertions, 24 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;
diff --git a/fs/nfsd/nfs4idmap.c b/fs/nfsd/nfs4idmap.c
index c78dbf493424..808b33a4a090 100644
--- a/fs/nfsd/nfs4idmap.c
+++ b/fs/nfsd/nfs4idmap.c
@@ -550,7 +550,7 @@ do_idmap_lookup_nowait(struct ent *(*lookup_fn)(struct ent *),
                 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()
                         || detail->flush_time > (*item)->h.last_refresh)
                 goto out_put;
         ret = -ENOENT;
diff --git a/include/linux/sunrpc/cache.h b/include/linux/sunrpc/cache.h
index 0e1febf4e5bc..ece432b7f87f 100644
--- a/include/linux/sunrpc/cache.h
+++ b/include/linux/sunrpc/cache.h
@@ -218,20 +218,42 @@ static inline int get_int(char **bpp, int *anint)
         return 0;
 }
 
+/*
+ * timestamps kept in the cache are expressed in seconds
+ * since boot.  This is the best for measuring differences in
+ * real time.
+ */
+static inline time_t seconds_since_boot(void)
+{
+        struct timespec boot;
+        getboottime(&boot);
+        return get_seconds() - boot.tv_sec;
+}
+
+static inline time_t convert_to_wallclock(time_t sinceboot)
+{
+        struct timespec boot;
+        getboottime(&boot);
+        return boot.tv_sec + sinceboot;
+}
+
 static inline time_t get_expiry(char **bpp)
 {
         int rv;
+        struct timespec boot;
+
         if (get_int(bpp, &rv))
                 return 0;
         if (rv < 0)
                 return 0;
-        return rv;
+        getboottime(&boot);
+        return rv - boot.tv_sec;
 }
 
 static inline void sunrpc_invalidate(struct cache_head *h,
                                      struct cache_detail *detail)
 {
-        h->expiry_time = get_seconds() - 1;
-        detail->nextcheck = get_seconds();
+        h->expiry_time = seconds_since_boot() - 1;
+        detail->nextcheck = seconds_since_boot();
 }
 #endif /*  _LINUX_SUNRPC_CACHE_H_ */
diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c
index 2b06410e584e..8dc121955fdc 100644
--- a/net/sunrpc/cache.c
+++ b/net/sunrpc/cache.c
@@ -42,7 +42,7 @@ static void cache_revisit_request(struct cache_head *item);
 
 static void cache_init(struct cache_head *h)
 {
-        time_t now = get_seconds();
+        time_t now = seconds_since_boot();
         h->next = NULL;
         h->flags = 0;
         kref_init(&h->ref);
@@ -52,7 +52,7 @@ static void cache_init(struct cache_head *h)
 
 static inline int cache_is_expired(struct cache_detail *detail, struct cache_head *h)
 {
-        return  (h->expiry_time < get_seconds()) ||
+        return  (h->expiry_time < seconds_since_boot()) ||
                 (detail->flush_time > h->last_refresh);
 }
 
@@ -127,7 +127,7 @@ static void cache_dequeue(struct cache_detail *detail, struct cache_head *ch);
 static void cache_fresh_locked(struct cache_head *head, time_t expiry)
 {
         head->expiry_time = expiry;
-        head->last_refresh = get_seconds();
+        head->last_refresh = seconds_since_boot();
         set_bit(CACHE_VALID, &head->flags);
 }
 
@@ -238,7 +238,7 @@ int cache_check(struct cache_detail *detail,
 
         /* now see if we want to start an upcall */
         refresh_age = (h->expiry_time - h->last_refresh);
-        age = get_seconds() - h->last_refresh;
+        age = seconds_since_boot() - h->last_refresh;
 
         if (rqstp == NULL) {
                 if (rv == -EAGAIN)
@@ -253,7 +253,7 @@ int cache_check(struct cache_detail *detail,
                                 cache_revisit_request(h);
                                 if (rv == -EAGAIN) {
                                         set_bit(CACHE_NEGATIVE, &h->flags);
-                                        cache_fresh_locked(h, get_seconds()+CACHE_NEW_EXPIRY);
+                                        cache_fresh_locked(h, seconds_since_boot()+CACHE_NEW_EXPIRY);
                                         cache_fresh_unlocked(h, detail);
                                         rv = -ENOENT;
                                 }
@@ -388,11 +388,11 @@ static int cache_clean(void)
                         return -1;
                 }
                 current_detail = list_entry(next, struct cache_detail, others);
-                if (current_detail->nextcheck > get_seconds())
+                if (current_detail->nextcheck > seconds_since_boot())
                         current_index = current_detail->hash_size;
                 else {
                         current_index = 0;
-                        current_detail->nextcheck = get_seconds()+30*60;
+                        current_detail->nextcheck = seconds_since_boot()+30*60;
                 }
         }
 
@@ -477,7 +477,7 @@ EXPORT_SYMBOL_GPL(cache_flush);
 void cache_purge(struct cache_detail *detail)
 {
         detail->flush_time = LONG_MAX;
-        detail->nextcheck = get_seconds();
+        detail->nextcheck = seconds_since_boot();
         cache_flush();
         detail->flush_time = 1;
 }
@@ -902,7 +902,7 @@ static int cache_release(struct inode *inode, struct file *filp,
                 filp->private_data = NULL;
                 kfree(rp);
 
-                cd->last_close = get_seconds();
+                cd->last_close = seconds_since_boot();
                 atomic_dec(&cd->readers);
         }
         module_put(cd->owner);
@@ -1034,7 +1034,7 @@ int sunrpc_cache_pipe_upcall(struct cache_detail *detail, struct cache_head *h,
         int len;
 
         if (atomic_read(&detail->readers) == 0 &&
-            detail->last_close < get_seconds() - 30) {
+            detail->last_close < seconds_since_boot() - 30) {
                         warn_no_listener(detail);
                         return -EINVAL;
         }
@@ -1219,7 +1219,8 @@ static int c_show(struct seq_file *m, void *p)
 
         ifdebug(CACHE)
                 seq_printf(m, "# expiry=%ld refcnt=%d flags=%lx\n",
-                           cp->expiry_time, atomic_read(&cp->ref.refcount), cp->flags);
+                           convert_to_wallclock(cp->expiry_time),
+                           atomic_read(&cp->ref.refcount), cp->flags);
         cache_get(cp);
         if (cache_check(cd, cp, NULL))
                 /* cache_check does a cache_put on failure */
@@ -1285,7 +1286,7 @@ static ssize_t read_flush(struct file *file, char __user *buf,
         unsigned long p = *ppos;
         size_t len;
 
-        sprintf(tbuf, "%lu\n", cd->flush_time);
+        sprintf(tbuf, "%lu\n", convert_to_wallclock(cd->flush_time));
         len = strlen(tbuf);
         if (p >= len)
                 return 0;
@@ -1303,19 +1304,20 @@ static ssize_t write_flush(struct file *file, const char __user *buf,
                            struct cache_detail *cd)
 {
         char tbuf[20];
-        char *ep;
-        long flushtime;
+        char *bp, *ep;
+
         if (*ppos || count > sizeof(tbuf)-1)
                 return -EINVAL;
         if (copy_from_user(tbuf, buf, count))
                 return -EFAULT;
         tbuf[count] = 0;
-        flushtime = simple_strtoul(tbuf, &ep, 0);
+        simple_strtoul(tbuf, &ep, 0);
         if (*ep && *ep != '\n')
                 return -EINVAL;
 
-        cd->flush_time = flushtime;
-        cd->nextcheck = get_seconds();
+        bp = tbuf;
+        cd->flush_time = get_expiry(&bp);
+        cd->nextcheck = seconds_since_boot();
         cache_flush();
 
         *ppos += count;