crypto: mcryptd - protect the per-CPU queue with a lock

[sagit-ice-cold/kernel_xiaomi_msm8998.git] / crypto / mcryptd.c

diff --git a/crypto/mcryptd.c b/crypto/mcryptd.c
index b4f3930..f620fe0 100644 (file)
--- a/crypto/mcryptd.c
+++ b/crypto/mcryptd.c
@@ -80,6 +80,7 @@ static int mcryptd_init_queue(struct mcryptd_queue *queue,
                pr_debug("cpu_queue #%d %p\n", cpu, queue->cpu_queue);
                crypto_init_queue(&cpu_queue->queue, max_cpu_qlen);
                INIT_WORK(&cpu_queue->work, mcryptd_queue_worker);
+               spin_lock_init(&cpu_queue->q_lock);
        }
        return 0;
 }
@@ -103,15 +104,16 @@ static int mcryptd_enqueue_request(struct mcryptd_queue *queue,
        int cpu, err;
        struct mcryptd_cpu_queue *cpu_queue;
 
-       cpu = get_cpu();
-       cpu_queue = this_cpu_ptr(queue->cpu_queue);
-       rctx->tag.cpu = cpu;
+       cpu_queue = raw_cpu_ptr(queue->cpu_queue);
+       spin_lock(&cpu_queue->q_lock);
+       cpu = smp_processor_id();
+       rctx->tag.cpu = smp_processor_id();
 
        err = crypto_enqueue_request(&cpu_queue->queue, request);
        pr_debug("enqueue request: cpu %d cpu_queue %p request %p\n",
                 cpu, cpu_queue, request);
+       spin_unlock(&cpu_queue->q_lock);
        queue_work_on(cpu, kcrypto_wq, &cpu_queue->work);
-       put_cpu();
 
        return err;
 }
@@ -164,16 +166,11 @@ static void mcryptd_queue_worker(struct work_struct *work)
        cpu_queue = container_of(work, struct mcryptd_cpu_queue, work);
        i = 0;
        while (i < MCRYPTD_BATCH || single_task_running()) {
-               /*
-                * preempt_disable/enable is used to prevent
-                * being preempted by mcryptd_enqueue_request()
-                */
-               local_bh_disable();
-               preempt_disable();
+
+               spin_lock_bh(&cpu_queue->q_lock);
                backlog = crypto_get_backlog(&cpu_queue->queue);
                req = crypto_dequeue_request(&cpu_queue->queue);
-               preempt_enable();
-               local_bh_enable();
+               spin_unlock_bh(&cpu_queue->q_lock);
 
                if (!req) {
                        mcryptd_opportunistic_flush();
@@ -188,7 +185,7 @@ static void mcryptd_queue_worker(struct work_struct *work)
                ++i;
        }
        if (cpu_queue->queue.qlen)
-               queue_work(kcrypto_wq, &cpu_queue->work);
+               queue_work_on(smp_processor_id(), kcrypto_wq, &cpu_queue->work);
 }
 
 void mcryptd_flusher(struct work_struct *__work)