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authorLinus Torvalds <torvalds@linux-foundation.org>2010-05-19 17:24:54 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2010-05-19 17:24:54 -0700
commitf72caf7e496465182eeda842ac66a5e75404ddf1 (patch)
tree682e2e4b34d6240ea5dbc516d368dd14b21de182 /net/sunrpc/cache.c
parent6a6be470c3071559970c5659354484d4f664050e (diff)
parente4e83ea47babd9d4bf95a13aed87f8ef51e46472 (diff)
Merge branch 'for-2.6.35' of git://linux-nfs.org/~bfields/linux
* 'for-2.6.35' of git://linux-nfs.org/~bfields/linux: (45 commits) Revert "nfsd4: distinguish expired from stale stateids" nfsd: safer initialization order in find_file() nfs4: minor callback code simplification, comment NFSD: don't report compiled-out versions as present nfsd4: implement reclaim_complete nfsd4: nfsd4_destroy_session must set callback client under the state lock nfsd4: keep a reference count on client while in use nfsd4: mark_client_expired nfsd4: introduce nfs4_client.cl_refcount nfsd4: refactor expire_client nfsd4: extend the client_lock to cover cl_lru nfsd4: use list_move in move_to_confirmed nfsd4: fold release_session into expire_client nfsd4: rename sessionid_lock to client_lock nfsd4: fix bare destroy_session null dereference nfsd4: use local variable in nfs4svc_encode_compoundres nfsd: further comment typos sunrpc: centralise most calls to svc_xprt_received nfsd4: fix unlikely race in session replay case nfsd4: fix filehandle comment ...
Diffstat (limited to 'net/sunrpc/cache.c')
-rw-r--r--net/sunrpc/cache.c45
1 files changed, 29 insertions, 16 deletions
diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c
index 77970fe8bff..c2173ebdb33 100644
--- a/net/sunrpc/cache.c
+++ b/net/sunrpc/cache.c
@@ -50,11 +50,17 @@ static void cache_init(struct cache_head *h)
h->last_refresh = now;
}
+static inline int cache_is_expired(struct cache_detail *detail, struct cache_head *h)
+{
+ return (h->expiry_time < get_seconds()) ||
+ (detail->flush_time > h->last_refresh);
+}
+
struct cache_head *sunrpc_cache_lookup(struct cache_detail *detail,
struct cache_head *key, int hash)
{
struct cache_head **head, **hp;
- struct cache_head *new = NULL;
+ struct cache_head *new = NULL, *freeme = NULL;
head = &detail->hash_table[hash];
@@ -63,6 +69,9 @@ struct cache_head *sunrpc_cache_lookup(struct cache_detail *detail,
for (hp=head; *hp != NULL ; hp = &(*hp)->next) {
struct cache_head *tmp = *hp;
if (detail->match(tmp, key)) {
+ if (cache_is_expired(detail, tmp))
+ /* This entry is expired, we will discard it. */
+ break;
cache_get(tmp);
read_unlock(&detail->hash_lock);
return tmp;
@@ -87,6 +96,13 @@ struct cache_head *sunrpc_cache_lookup(struct cache_detail *detail,
for (hp=head; *hp != NULL ; hp = &(*hp)->next) {
struct cache_head *tmp = *hp;
if (detail->match(tmp, key)) {
+ if (cache_is_expired(detail, tmp)) {
+ *hp = tmp->next;
+ tmp->next = NULL;
+ detail->entries --;
+ freeme = tmp;
+ break;
+ }
cache_get(tmp);
write_unlock(&detail->hash_lock);
cache_put(new, detail);
@@ -99,6 +115,8 @@ struct cache_head *sunrpc_cache_lookup(struct cache_detail *detail,
cache_get(new);
write_unlock(&detail->hash_lock);
+ if (freeme)
+ cache_put(freeme, detail);
return new;
}
EXPORT_SYMBOL_GPL(sunrpc_cache_lookup);
@@ -184,10 +202,7 @@ static int cache_make_upcall(struct cache_detail *cd, struct cache_head *h)
static inline int cache_is_valid(struct cache_detail *detail, struct cache_head *h)
{
- if (!test_bit(CACHE_VALID, &h->flags) ||
- h->expiry_time < get_seconds())
- return -EAGAIN;
- else if (detail->flush_time > h->last_refresh)
+ if (!test_bit(CACHE_VALID, &h->flags))
return -EAGAIN;
else {
/* entry is valid */
@@ -398,31 +413,27 @@ static int cache_clean(void)
/* Ok, now to clean this strand */
cp = & current_detail->hash_table[current_index];
- ch = *cp;
- for (; ch; cp= & ch->next, ch= *cp) {
+ for (ch = *cp ; ch ; cp = & ch->next, ch = *cp) {
if (current_detail->nextcheck > ch->expiry_time)
current_detail->nextcheck = ch->expiry_time+1;
- if (ch->expiry_time >= get_seconds() &&
- ch->last_refresh >= current_detail->flush_time)
+ if (!cache_is_expired(current_detail, ch))
continue;
- if (test_and_clear_bit(CACHE_PENDING, &ch->flags))
- cache_dequeue(current_detail, ch);
- if (atomic_read(&ch->ref.refcount) == 1)
- break;
- }
- if (ch) {
*cp = ch->next;
ch->next = NULL;
current_detail->entries--;
rv = 1;
+ break;
}
+
write_unlock(&current_detail->hash_lock);
d = current_detail;
if (!ch)
current_index ++;
spin_unlock(&cache_list_lock);
if (ch) {
+ if (test_and_clear_bit(CACHE_PENDING, &ch->flags))
+ cache_dequeue(current_detail, ch);
cache_revisit_request(ch);
cache_put(ch, d);
}
@@ -1234,8 +1245,10 @@ static int content_open(struct inode *inode, struct file *file,
if (!cd || !try_module_get(cd->owner))
return -EACCES;
han = __seq_open_private(file, &cache_content_op, sizeof(*han));
- if (han == NULL)
+ if (han == NULL) {
+ module_put(cd->owner);
return -ENOMEM;
+ }
han->cd = cd;
return 0;