1 files changed, 80 insertions, 0 deletions

diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index a74972b07e74..fbe544761628 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c
@@ -221,6 +221,86 @@ const struct bpf_func_proto bpf_get_current_comm_proto = {
         .arg2_type      = ARG_CONST_SIZE,
 };
 
+#if defined(CONFIG_QUEUED_SPINLOCKS) || defined(CONFIG_BPF_ARCH_SPINLOCK)
+
+static inline void __bpf_spin_lock(struct bpf_spin_lock *lock)
+{
+        arch_spinlock_t *l = (void *)lock;
+        union {
+                __u32 val;
+                arch_spinlock_t lock;
+        } u = { .lock = __ARCH_SPIN_LOCK_UNLOCKED };
+
+        compiletime_assert(u.val == 0, "__ARCH_SPIN_LOCK_UNLOCKED not 0");
+        BUILD_BUG_ON(sizeof(*l) != sizeof(__u32));
+        BUILD_BUG_ON(sizeof(*lock) != sizeof(__u32));
+        arch_spin_lock(l);
+}
+
+static inline void __bpf_spin_unlock(struct bpf_spin_lock *lock)
+{
+        arch_spinlock_t *l = (void *)lock;
+
+        arch_spin_unlock(l);
+}
+
+#else
+
+static inline void __bpf_spin_lock(struct bpf_spin_lock *lock)
+{
+        atomic_t *l = (void *)lock;
+
+        BUILD_BUG_ON(sizeof(*l) != sizeof(*lock));
+        do {
+                atomic_cond_read_relaxed(l, !VAL);
+        } while (atomic_xchg(l, 1));
+}
+
+static inline void __bpf_spin_unlock(struct bpf_spin_lock *lock)
+{
+        atomic_t *l = (void *)lock;
+
+        atomic_set_release(l, 0);
+}
+
+#endif
+
+static DEFINE_PER_CPU(unsigned long, irqsave_flags);
+
+notrace BPF_CALL_1(bpf_spin_lock, struct bpf_spin_lock *, lock)
+{
+        unsigned long flags;
+
+        local_irq_save(flags);
+        __bpf_spin_lock(lock);
+        __this_cpu_write(irqsave_flags, flags);
+        return 0;
+}
+
+const struct bpf_func_proto bpf_spin_lock_proto = {
+        .func           = bpf_spin_lock,
+        .gpl_only       = false,
+        .ret_type       = RET_VOID,
+        .arg1_type      = ARG_PTR_TO_SPIN_LOCK,
+};
+
+notrace BPF_CALL_1(bpf_spin_unlock, struct bpf_spin_lock *, lock)
+{
+        unsigned long flags;
+
+        flags = __this_cpu_read(irqsave_flags);
+        __bpf_spin_unlock(lock);
+        local_irq_restore(flags);
+        return 0;
+}
+
+const struct bpf_func_proto bpf_spin_unlock_proto = {
+        .func           = bpf_spin_unlock,
+        .gpl_only       = false,
+        .ret_type       = RET_VOID,
+        .arg1_type      = ARG_PTR_TO_SPIN_LOCK,
+};
+
 #ifdef CONFIG_CGROUPS
 BPF_CALL_0(bpf_get_current_cgroup_id)
 {