nfsd: add more granular locking to forget_locks fault injector
...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 b661294..48ae0a6 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -5723,6 +5723,12 @@
}
#ifdef CONFIG_NFSD_FAULT_INJECTION
+static inline void
+put_client(struct nfs4_client *clp)
+{
+ atomic_dec(&clp->cl_refcount);
+}
+
u64
nfsd_inject_print_clients(struct nfsd_fault_inject_op *op)
{
@@ -5810,6 +5816,22 @@
printk(KERN_INFO "NFS Client: %s has %u %s\n", buf, count, type);
}
+static void
+nfsd_inject_add_lock_to_list(struct nfs4_ol_stateid *lst,
+ struct list_head *collect)
+{
+ struct nfs4_client *clp = lst->st_stid.sc_client;
+ struct nfsd_net *nn = net_generic(current->nsproxy->net_ns,
+ nfsd_net_id);
+
+ if (!collect)
+ return;
+
+ lockdep_assert_held(&nn->client_lock);
+ atomic_inc(&clp->cl_refcount);
+ list_add(&lst->st_locks, collect);
+}
+
static u64 nfsd_foreach_client_lock(struct nfs4_client *clp, u64 max,
struct list_head *collect,
void (*func)(struct nfs4_ol_stateid *))
@@ -5819,6 +5841,7 @@
struct nfs4_ol_stateid *lst, *lst_next;
u64 count = 0;
+ spin_lock(&clp->cl_lock);
list_for_each_entry(oop, &clp->cl_openowners, oo_perclient) {
list_for_each_entry_safe(stp, st_next,
&oop->oo_owner.so_stateids, st_perstateowner) {
@@ -5826,31 +5849,122 @@
&stp->st_locks, st_locks) {
if (func) {
func(lst);
- if (collect)
- list_add(&lst->st_locks,
- collect);
+ nfsd_inject_add_lock_to_list(lst,
+ collect);
}
- if (++count == max)
- return count;
+ ++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)
+ goto out;
}
}
}
+out:
+ spin_unlock(&clp->cl_lock);
return count;
}
-u64 nfsd_forget_client_locks(struct nfs4_client *clp, u64 max)
+static u64
+nfsd_collect_client_locks(struct nfs4_client *clp, struct list_head *collect,
+ u64 max)
{
- return nfsd_foreach_client_lock(clp, max, NULL, release_lock_stateid);
+ return nfsd_foreach_client_lock(clp, max, collect, unhash_lock_stateid);
}
-u64 nfsd_print_client_locks(struct nfs4_client *clp, u64 max)
+static u64
+nfsd_print_client_locks(struct nfs4_client *clp)
{
- u64 count = nfsd_foreach_client_lock(clp, max, NULL, NULL);
+ u64 count = nfsd_foreach_client_lock(clp, 0, NULL, NULL);
nfsd_print_count(clp, count, "locked files");
return count;
}
+u64
+nfsd_inject_print_locks(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_locks(clp);
+ spin_unlock(&nn->client_lock);
+
+ return count;
+}
+
+static void
+nfsd_reap_locks(struct list_head *reaplist)
+{
+ struct nfs4_client *clp;
+ struct nfs4_ol_stateid *stp, *next;
+
+ list_for_each_entry_safe(stp, next, reaplist, st_locks) {
+ list_del_init(&stp->st_locks);
+ clp = stp->st_stid.sc_client;
+ nfs4_put_stid(&stp->st_stid);
+ put_client(clp);
+ }
+}
+
+u64
+nfsd_inject_forget_client_locks(struct nfsd_fault_inject_op *op,
+ struct sockaddr_storage *addr, size_t addr_size)
+{
+ unsigned int 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_collect_client_locks(clp, &reaplist, 0);
+ spin_unlock(&nn->client_lock);
+ nfsd_reap_locks(&reaplist);
+ return count;
+}
+
+u64
+nfsd_inject_forget_locks(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_collect_client_locks(clp, &reaplist, max - count);
+ if (max != 0 && count >= max)
+ break;
+ }
+ spin_unlock(&nn->client_lock);
+ nfsd_reap_locks(&reaplist);
+ return count;
+}
+
static u64 nfsd_foreach_client_open(struct nfs4_client *clp, u64 max, void (*func)(struct nfs4_openowner *))
{
struct nfs4_openowner *oop, *next;