nfsd: add more granular locking to *_delegations fault injectors
...instead of relying on the client_mutex.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 20bffa8..d18bbb1 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -6102,9 +6102,13 @@
struct list_head *victims)
{
struct nfs4_delegation *dp, *next;
+ struct nfsd_net *nn = net_generic(current->nsproxy->net_ns,
+ nfsd_net_id);
u64 count = 0;
- lockdep_assert_held(&state_lock);
+ lockdep_assert_held(&nn->client_lock);
+
+ spin_lock(&state_lock);
list_for_each_entry_safe(dp, next, &clp->cl_delegations, dl_perclnt) {
if (victims) {
/*
@@ -6116,70 +6120,189 @@
if (dp->dl_time != 0)
continue;
+ atomic_inc(&clp->cl_refcount);
unhash_delegation_locked(dp);
list_add(&dp->dl_recall_lru, victims);
}
- if (++count == max)
+ ++count;
+ /*
+ * Despite the fact that these functions deal with
+ * 64-bit integers for "count", we must ensure that
+ * it doesn't blow up the clp->cl_refcount. Throw a
+ * warning if we start to approach INT_MAX here.
+ */
+ WARN_ON_ONCE(count == (INT_MAX / 2));
+ if (count == max)
break;
}
+ spin_unlock(&state_lock);
return count;
}
-u64 nfsd_forget_client_delegations(struct nfs4_client *clp, u64 max)
+static u64
+nfsd_print_client_delegations(struct nfs4_client *clp)
{
- struct nfs4_delegation *dp, *next;
- LIST_HEAD(victims);
- u64 count;
-
- spin_lock(&state_lock);
- count = nfsd_find_all_delegations(clp, max, &victims);
- spin_unlock(&state_lock);
-
- list_for_each_entry_safe(dp, next, &victims, dl_recall_lru) {
- list_del_init(&dp->dl_recall_lru);
- revoke_delegation(dp);
- }
-
- return count;
-}
-
-u64 nfsd_recall_client_delegations(struct nfs4_client *clp, u64 max)
-{
- struct nfs4_delegation *dp;
- LIST_HEAD(victims);
- u64 count;
-
- spin_lock(&state_lock);
- count = nfsd_find_all_delegations(clp, max, &victims);
- while (!list_empty(&victims)) {
- dp = list_first_entry(&victims, struct nfs4_delegation,
- dl_recall_lru);
- list_del_init(&dp->dl_recall_lru);
- dp->dl_time = 0;
- nfsd_break_one_deleg(dp);
- }
- spin_unlock(&state_lock);
-
- return count;
-}
-
-u64 nfsd_print_client_delegations(struct nfs4_client *clp, u64 max)
-{
- u64 count = 0;
-
- spin_lock(&state_lock);
- count = nfsd_find_all_delegations(clp, max, NULL);
- spin_unlock(&state_lock);
+ u64 count = nfsd_find_all_delegations(clp, 0, NULL);
nfsd_print_count(clp, count, "delegations");
return count;
}
+u64
+nfsd_inject_print_delegations(struct nfsd_fault_inject_op *op)
+{
+ struct nfs4_client *clp;
+ u64 count = 0;
+ struct nfsd_net *nn = net_generic(current->nsproxy->net_ns,
+ nfsd_net_id);
+
+ if (!nfsd_netns_ready(nn))
+ return 0;
+
+ spin_lock(&nn->client_lock);
+ list_for_each_entry(clp, &nn->client_lru, cl_lru)
+ count += nfsd_print_client_delegations(clp);
+ spin_unlock(&nn->client_lock);
+
+ return count;
+}
+
+static void
+nfsd_forget_delegations(struct list_head *reaplist)
+{
+ struct nfs4_client *clp;
+ struct nfs4_delegation *dp, *next;
+
+ list_for_each_entry_safe(dp, next, reaplist, dl_recall_lru) {
+ list_del_init(&dp->dl_recall_lru);
+ clp = dp->dl_stid.sc_client;
+ revoke_delegation(dp);
+ put_client(clp);
+ }
+}
+
+u64
+nfsd_inject_forget_client_delegations(struct nfsd_fault_inject_op *op,
+ struct sockaddr_storage *addr, size_t addr_size)
+{
+ u64 count = 0;
+ struct nfs4_client *clp;
+ struct nfsd_net *nn = net_generic(current->nsproxy->net_ns,
+ nfsd_net_id);
+ LIST_HEAD(reaplist);
+
+ if (!nfsd_netns_ready(nn))
+ return count;
+
+ spin_lock(&nn->client_lock);
+ clp = nfsd_find_client(addr, addr_size);
+ if (clp)
+ count = nfsd_find_all_delegations(clp, 0, &reaplist);
+ spin_unlock(&nn->client_lock);
+
+ nfsd_forget_delegations(&reaplist);
+ return count;
+}
+
+u64
+nfsd_inject_forget_delegations(struct nfsd_fault_inject_op *op, u64 max)
+{
+ u64 count = 0;
+ struct nfs4_client *clp;
+ struct nfsd_net *nn = net_generic(current->nsproxy->net_ns,
+ nfsd_net_id);
+ LIST_HEAD(reaplist);
+
+ if (!nfsd_netns_ready(nn))
+ return count;
+
+ spin_lock(&nn->client_lock);
+ list_for_each_entry(clp, &nn->client_lru, cl_lru) {
+ count += nfsd_find_all_delegations(clp, max - count, &reaplist);
+ if (max != 0 && count >= max)
+ break;
+ }
+ spin_unlock(&nn->client_lock);
+ nfsd_forget_delegations(&reaplist);
+ return count;
+}
+
+static void
+nfsd_recall_delegations(struct list_head *reaplist)
+{
+ struct nfs4_client *clp;
+ struct nfs4_delegation *dp, *next;
+
+ list_for_each_entry_safe(dp, next, reaplist, dl_recall_lru) {
+ list_del_init(&dp->dl_recall_lru);
+ clp = dp->dl_stid.sc_client;
+ /*
+ * We skipped all entries that had a zero dl_time before,
+ * so we can now reset the dl_time back to 0. If a delegation
+ * break comes in now, then it won't make any difference since
+ * we're recalling it either way.
+ */
+ spin_lock(&state_lock);
+ dp->dl_time = 0;
+ spin_unlock(&state_lock);
+ nfsd_break_one_deleg(dp);
+ put_client(clp);
+ }
+}
+
+u64
+nfsd_inject_recall_client_delegations(struct nfsd_fault_inject_op *op,
+ struct sockaddr_storage *addr,
+ size_t addr_size)
+{
+ u64 count = 0;
+ struct nfs4_client *clp;
+ struct nfsd_net *nn = net_generic(current->nsproxy->net_ns,
+ nfsd_net_id);
+ LIST_HEAD(reaplist);
+
+ if (!nfsd_netns_ready(nn))
+ return count;
+
+ spin_lock(&nn->client_lock);
+ clp = nfsd_find_client(addr, addr_size);
+ if (clp)
+ count = nfsd_find_all_delegations(clp, 0, &reaplist);
+ spin_unlock(&nn->client_lock);
+
+ nfsd_recall_delegations(&reaplist);
+ return count;
+}
+
+u64
+nfsd_inject_recall_delegations(struct nfsd_fault_inject_op *op, u64 max)
+{
+ u64 count = 0;
+ struct nfs4_client *clp, *next;
+ struct nfsd_net *nn = net_generic(current->nsproxy->net_ns,
+ nfsd_net_id);
+ LIST_HEAD(reaplist);
+
+ if (!nfsd_netns_ready(nn))
+ return count;
+
+ spin_lock(&nn->client_lock);
+ list_for_each_entry_safe(clp, next, &nn->client_lru, cl_lru) {
+ count += nfsd_find_all_delegations(clp, max - count, &reaplist);
+ if (max != 0 && ++count >= max)
+ break;
+ }
+ spin_unlock(&nn->client_lock);
+ nfsd_recall_delegations(&reaplist);
+ return count;
+}
+
u64 nfsd_for_n_state(u64 max, u64 (*func)(struct nfs4_client *, u64))
{
struct nfs4_client *clp, *next;
u64 count = 0;
- struct nfsd_net *nn = net_generic(current->nsproxy->net_ns, nfsd_net_id);
+ struct nfsd_net *nn = net_generic(current->nsproxy->net_ns,
+ nfsd_net_id);
if (!nfsd_netns_ready(nn))
return 0;