2 files changed, 104 insertions, 117 deletions

diff --git a/crypto/Kconfig b/crypto/Kconfig
index 420b630a17cf..24c31efde882 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -114,6 +114,7 @@ config CRYPTO_CRYPTD
         select CRYPTO_BLKCIPHER
         select CRYPTO_HASH
         select CRYPTO_MANAGER
+        select CRYPTO_WORKQUEUE
         help
           This is a generic software asynchronous crypto daemon that
           converts an arbitrary synchronous software crypto algorithm
diff --git a/crypto/cryptd.c b/crypto/cryptd.c
index 93b98c525b3a..d14b22658d7a 100644
--- a/crypto/cryptd.c
+++ b/crypto/cryptd.c
@@ -13,30 +13,30 @@
 #include <crypto/algapi.h>
 #include <crypto/internal/hash.h>
 #include <crypto/cryptd.h>
+#include <crypto/crypto_wq.h>
 #include <linux/err.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
-#include <linux/kthread.h>
 #include <linux/list.h>
 #include <linux/module.h>
-#include <linux/mutex.h>
 #include <linux/scatterlist.h>
 #include <linux/sched.h>
 #include <linux/slab.h>
-#include <linux/spinlock.h>
 
-#define CRYPTD_MAX_QLEN 100
+#define CRYPTD_MAX_CPU_QLEN 100
 
-struct cryptd_state {
-        spinlock_t lock;
-        struct mutex mutex;
+struct cryptd_cpu_queue {
         struct crypto_queue queue;
-        struct task_struct *task;
+        struct work_struct work;
+};
+
+struct cryptd_queue {
+        struct cryptd_cpu_queue *cpu_queue;
 };
 
 struct cryptd_instance_ctx {
         struct crypto_spawn spawn;
-        struct cryptd_state *state;
+        struct cryptd_queue *queue;
 };
 
 struct cryptd_blkcipher_ctx {
@@ -55,11 +55,85 @@ struct cryptd_hash_request_ctx {
         crypto_completion_t complete;
 };
 
-static inline struct cryptd_state *cryptd_get_state(struct crypto_tfm *tfm)
+static void cryptd_queue_worker(struct work_struct *work);
+
+static int cryptd_init_queue(struct cryptd_queue *queue,
+                             unsigned int max_cpu_qlen)
+{
+        int cpu;
+        struct cryptd_cpu_queue *cpu_queue;
+
+        queue->cpu_queue = alloc_percpu(struct cryptd_cpu_queue);
+        if (!queue->cpu_queue)
+                return -ENOMEM;
+        for_each_possible_cpu(cpu) {
+                cpu_queue = per_cpu_ptr(queue->cpu_queue, cpu);
+                crypto_init_queue(&cpu_queue->queue, max_cpu_qlen);
+                INIT_WORK(&cpu_queue->work, cryptd_queue_worker);
+        }
+        return 0;
+}
+
+static void cryptd_fini_queue(struct cryptd_queue *queue)
+{
+        int cpu;
+        struct cryptd_cpu_queue *cpu_queue;
+
+        for_each_possible_cpu(cpu) {
+                cpu_queue = per_cpu_ptr(queue->cpu_queue, cpu);
+                BUG_ON(cpu_queue->queue.qlen);
+        }
+        free_percpu(queue->cpu_queue);
+}
+
+static int cryptd_enqueue_request(struct cryptd_queue *queue,
+                                  struct crypto_async_request *request)
+{
+        int cpu, err;
+        struct cryptd_cpu_queue *cpu_queue;
+
+        cpu = get_cpu();
+        cpu_queue = per_cpu_ptr(queue->cpu_queue, cpu);
+        err = crypto_enqueue_request(&cpu_queue->queue, request);
+        queue_work_on(cpu, kcrypto_wq, &cpu_queue->work);
+        put_cpu();
+
+        return err;
+}
+
+/* Called in workqueue context, do one real cryption work (via
+ * req->complete) and reschedule itself if there are more work to
+ * do. */
+static void cryptd_queue_worker(struct work_struct *work)
+{
+        struct cryptd_cpu_queue *cpu_queue;
+        struct crypto_async_request *req, *backlog;
+
+        cpu_queue = container_of(work, struct cryptd_cpu_queue, work);
+        /* Only handle one request at a time to avoid hogging crypto
+         * workqueue. preempt_disable/enable is used to prevent
+         * being preempted by cryptd_enqueue_request() */
+        preempt_disable();
+        backlog = crypto_get_backlog(&cpu_queue->queue);
+        req = crypto_dequeue_request(&cpu_queue->queue);
+        preempt_enable();
+
+        if (!req)
+                return;
+
+        if (backlog)
+                backlog->complete(backlog, -EINPROGRESS);
+        req->complete(req, 0);
+
+        if (cpu_queue->queue.qlen)
+                queue_work(kcrypto_wq, &cpu_queue->work);
+}
+
+static inline struct cryptd_queue *cryptd_get_queue(struct crypto_tfm *tfm)
 {
         struct crypto_instance *inst = crypto_tfm_alg_instance(tfm);
         struct cryptd_instance_ctx *ictx = crypto_instance_ctx(inst);
-        return ictx->state;
+        return ictx->queue;
 }
 
 static int cryptd_blkcipher_setkey(struct crypto_ablkcipher *parent,
@@ -131,19 +205,13 @@ static int cryptd_blkcipher_enqueue(struct ablkcipher_request *req,
 {
         struct cryptd_blkcipher_request_ctx *rctx = ablkcipher_request_ctx(req);
         struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req);
-        struct cryptd_state *state =
-                cryptd_get_state(crypto_ablkcipher_tfm(tfm));
-        int err;
+        struct cryptd_queue *queue;
 
+        queue = cryptd_get_queue(crypto_ablkcipher_tfm(tfm));
         rctx->complete = req->base.complete;
         req->base.complete = complete;
 
-        spin_lock_bh(&state->lock);
-        err = ablkcipher_enqueue_request(&state->queue, req);
-        spin_unlock_bh(&state->lock);
-
-        wake_up_process(state->task);
-        return err;
+        return cryptd_enqueue_request(queue, &req->base);
 }
 
 static int cryptd_blkcipher_encrypt_enqueue(struct ablkcipher_request *req)
@@ -177,21 +245,12 @@ static int cryptd_blkcipher_init_tfm(struct crypto_tfm *tfm)
 static void cryptd_blkcipher_exit_tfm(struct crypto_tfm *tfm)
 {
         struct cryptd_blkcipher_ctx *ctx = crypto_tfm_ctx(tfm);
-        struct cryptd_state *state = cryptd_get_state(tfm);
-        int active;
-
-        mutex_lock(&state->mutex);
-        active = ablkcipher_tfm_in_queue(&state->queue,
-                                         __crypto_ablkcipher_cast(tfm));
-        mutex_unlock(&state->mutex);
-
-        BUG_ON(active);
 
         crypto_free_blkcipher(ctx->child);
 }
 
 static struct crypto_instance *cryptd_alloc_instance(struct crypto_alg *alg,
-                                                     struct cryptd_state *state)
+                                                     struct cryptd_queue *queue)
 {
         struct crypto_instance *inst;
         struct cryptd_instance_ctx *ctx;
@@ -214,7 +273,7 @@ static struct crypto_instance *cryptd_alloc_instance(struct crypto_alg *alg,
         if (err)
                 goto out_free_inst;
 
-        ctx->state = state;
+        ctx->queue = queue;
 
         memcpy(inst->alg.cra_name, alg->cra_name, CRYPTO_MAX_ALG_NAME);
 
@@ -232,7 +291,7 @@ out_free_inst:
 }
 
 static struct crypto_instance *cryptd_alloc_blkcipher(
-        struct rtattr **tb, struct cryptd_state *state)
+        struct rtattr **tb, struct cryptd_queue *queue)
 {
         struct crypto_instance *inst;
         struct crypto_alg *alg;
@@ -242,7 +301,7 @@ static struct crypto_instance *cryptd_alloc_blkcipher(
         if (IS_ERR(alg))
                 return ERR_CAST(alg);
 
-        inst = cryptd_alloc_instance(alg, state);
+        inst = cryptd_alloc_instance(alg, queue);
         if (IS_ERR(inst))
                 goto out_put_alg;
 
@@ -290,15 +349,6 @@ static int cryptd_hash_init_tfm(struct crypto_tfm *tfm)
 static void cryptd_hash_exit_tfm(struct crypto_tfm *tfm)
 {
         struct cryptd_hash_ctx *ctx = crypto_tfm_ctx(tfm);
-        struct cryptd_state *state = cryptd_get_state(tfm);
-        int active;
-
-        mutex_lock(&state->mutex);
-        active = ahash_tfm_in_queue(&state->queue,
-                                __crypto_ahash_cast(tfm));
-        mutex_unlock(&state->mutex);
-
-        BUG_ON(active);
 
         crypto_free_hash(ctx->child);
 }
@@ -324,19 +374,13 @@ static int cryptd_hash_enqueue(struct ahash_request *req,
 {
         struct cryptd_hash_request_ctx *rctx = ahash_request_ctx(req);
         struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
-        struct cryptd_state *state =
-                cryptd_get_state(crypto_ahash_tfm(tfm));
-        int err;
+        struct cryptd_queue *queue =
+                cryptd_get_queue(crypto_ahash_tfm(tfm));
 
         rctx->complete = req->base.complete;
         req->base.complete = complete;
 
-        spin_lock_bh(&state->lock);
-        err = ahash_enqueue_request(&state->queue, req);
-        spin_unlock_bh(&state->lock);
-
-        wake_up_process(state->task);
-        return err;
+        return cryptd_enqueue_request(queue, &req->base);
 }
 
 static void cryptd_hash_init(struct crypto_async_request *req_async, int err)
@@ -469,7 +513,7 @@ static int cryptd_hash_digest_enqueue(struct ahash_request *req)
 }
 
 static struct crypto_instance *cryptd_alloc_hash(
-        struct rtattr **tb, struct cryptd_state *state)
+        struct rtattr **tb, struct cryptd_queue *queue)
 {
         struct crypto_instance *inst;
         struct crypto_alg *alg;
@@ -479,7 +523,7 @@ static struct crypto_instance *cryptd_alloc_hash(
         if (IS_ERR(alg))
                 return ERR_PTR(PTR_ERR(alg));
 
-        inst = cryptd_alloc_instance(alg, state);
+        inst = cryptd_alloc_instance(alg, queue);
         if (IS_ERR(inst))
                 goto out_put_alg;
 
@@ -503,7 +547,7 @@ out_put_alg:
         return inst;
 }
 
-static struct cryptd_state state;
+static struct cryptd_queue queue;
 
 static struct crypto_instance *cryptd_alloc(struct rtattr **tb)
 {
@@ -515,9 +559,9 @@ static struct crypto_instance *cryptd_alloc(struct rtattr **tb)
 
         switch (algt->type & algt->mask & CRYPTO_ALG_TYPE_MASK) {
         case CRYPTO_ALG_TYPE_BLKCIPHER:
-                return cryptd_alloc_blkcipher(tb, &state);
+                return cryptd_alloc_blkcipher(tb, &queue);
         case CRYPTO_ALG_TYPE_DIGEST:
-                return cryptd_alloc_hash(tb, &state);
+                return cryptd_alloc_hash(tb, &queue);
         }
 
         return ERR_PTR(-EINVAL);
@@ -572,82 +616,24 @@ void cryptd_free_ablkcipher(struct cryptd_ablkcipher *tfm)
 }
 EXPORT_SYMBOL_GPL(cryptd_free_ablkcipher);
 
-static inline int cryptd_create_thread(struct cryptd_state *state,
-                                       int (*fn)(void *data), const char *name)
-{
-        spin_lock_init(&state->lock);
-        mutex_init(&state->mutex);
-        crypto_init_queue(&state->queue, CRYPTD_MAX_QLEN);
-
-        state->task = kthread_run(fn, state, name);
-        if (IS_ERR(state->task))
-                return PTR_ERR(state->task);
-
-        return 0;
-}
-
-static inline void cryptd_stop_thread(struct cryptd_state *state)
-{
-        BUG_ON(state->queue.qlen);
-        kthread_stop(state->task);
-}
-
-static int cryptd_thread(void *data)
-{
-        struct cryptd_state *state = data;
-        int stop;
-
-        current->flags |= PF_NOFREEZE;
-
-        do {
-                struct crypto_async_request *req, *backlog;
-
-                mutex_lock(&state->mutex);
-                __set_current_state(TASK_INTERRUPTIBLE);
-
-                spin_lock_bh(&state->lock);
-                backlog = crypto_get_backlog(&state->queue);
-                req = crypto_dequeue_request(&state->queue);
-                spin_unlock_bh(&state->lock);
-
-                stop = kthread_should_stop();
-
-                if (stop || req) {
-                        __set_current_state(TASK_RUNNING);
-                        if (req) {
-                                if (backlog)
-                                        backlog->complete(backlog,
-                                                          -EINPROGRESS);
-                                req->complete(req, 0);
-                        }
-                }
-
-                mutex_unlock(&state->mutex);
-
-                schedule();
-        } while (!stop);
-
-        return 0;
-}
-
 static int __init cryptd_init(void)
 {
         int err;
 
-        err = cryptd_create_thread(&state, cryptd_thread, "cryptd");
+        err = cryptd_init_queue(&queue, CRYPTD_MAX_CPU_QLEN);
         if (err)
                 return err;
 
         err = crypto_register_template(&cryptd_tmpl);
         if (err)
-                kthread_stop(state.task);
+                cryptd_fini_queue(&queue);
 
         return err;
 }
 
 static void __exit cryptd_exit(void)
 {
-        cryptd_stop_thread(&state);
+        cryptd_fini_queue(&queue);
         crypto_unregister_template(&cryptd_tmpl);
 }