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>
diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c
index 2b06410..8dc1219 100644
--- a/net/sunrpc/cache.c
+++ b/net/sunrpc/cache.c
@@ -42,7 +42,7 @@
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 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_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 @@
/* 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 @@
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 @@
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 @@
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 @@
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 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 @@
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 @@
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 @@
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;
