[PATCH 5.18 143/158] crypto: qat - add backlog mechanism

Greg Kroah-Hartman
2022-07-27T17:45:15Z

From: Giovanni Cabiddu <giovanni.cabiddu@intel.com>

[ Upstream commit 38682383973280e5be2802ba8a8d4a636d36cb19 ]

The implementations of the crypto algorithms (aead, skcipher, etc) in
the QAT driver do not properly support requests with the
CRYPTO_TFM_REQ_MAY_BACKLOG flag set. If the HW queue is full, the driver
returns -EBUSY but does not enqueue the request. This can result in
applications like dm-crypt waiting indefinitely for the completion of a
request that was never submitted to the hardware.

Fix this by adding a software backlog queue: if the ring buffer is more
than eighty percent full, then the request is enqueued to a backlog
list and the error code -EBUSY is returned back to the caller.
Requests in the backlog queue are resubmitted at a later time, in the
context of the callback of a previously submitted request.
The request for which -EBUSY is returned is then marked as -EINPROGRESS
once submitted to the HW queues.

The submission loop inside the function qat_alg_send_message() has been
modified to decide which submission policy to use based on the request
flags. If the request does not have the CRYPTO_TFM_REQ_MAY_BACKLOG set,
the previous behaviour has been preserved.

Based on a patch by
Vishnu Das Ramachandran <vishnu.dasx.ramachandran@intel.com>

Cc: stable@vger.kernel.org
Fixes: d370cec32194 ("crypto: qat - Intel(R) QAT crypto interface")
Reported-by: Mikulas Patocka <mpatocka@redhat.com>
Reported-by: Kyle Sanderson <kyle.leet@gmail.com>
Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Reviewed-by: Marco Chiappero <marco.chiappero@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/crypto/qat/qat_common/adf_transport.c | 11 +++
drivers/crypto/qat/qat_common/adf_transport.h | 1 +
.../qat/qat_common/adf_transport_internal.h | 1 +
drivers/crypto/qat/qat_common/qat_algs.c | 24 ++++---
drivers/crypto/qat/qat_common/qat_algs_send.c | 67 ++++++++++++++++++-
drivers/crypto/qat/qat_common/qat_algs_send.h | 1 +
drivers/crypto/qat/qat_common/qat_asym_algs.c | 23 ++++---
drivers/crypto/qat/qat_common/qat_crypto.c | 3 +
drivers/crypto/qat/qat_common/qat_crypto.h | 10 +++
9 files changed, 123 insertions(+), 18 deletions(-)

diff --git a/drivers/crypto/qat/qat_common/adf_transport.c b/drivers/crypto/qat/qat_common/adf_transport.c
index 8ba28409fb74..630d0483c4e0 100644
--- a/drivers/crypto/qat/qat_common/adf_transport.c
+++ b/drivers/crypto/qat/qat_common/adf_transport.c
@@ -8,6 +8,9 @@
#include "adf_cfg.h"
#include "adf_common_drv.h"

+#define ADF_MAX_RING_THRESHOLD 80
+#define ADF_PERCENT(tot, percent) (((tot) * (percent)) / 100)
+
static inline u32 adf_modulo(u32 data, u32 shift)
{
u32 div = data >> shift;
@@ -77,6 +80,11 @@ static void adf_disable_ring_irq(struct adf_etr_bank_data *bank, u32 ring)
bank->irq_mask);
}

+bool adf_ring_nearly_full(struct adf_etr_ring_data *ring)
+{
+ return atomic_read(ring->inflights) > ring->threshold;
+}
+
int adf_send_message(struct adf_etr_ring_data *ring, u32 *msg)
{
struct adf_hw_csr_ops *csr_ops = GET_CSR_OPS(ring->bank->accel_dev);
@@ -217,6 +225,7 @@ int adf_create_ring(struct adf_accel_dev *accel_dev, const char *section,
struct adf_etr_bank_data *bank;
struct adf_etr_ring_data *ring;
char val[ADF_CFG_MAX_VAL_LEN_IN_BYTES];
+ int max_inflights;
u32 ring_num;
int ret;

@@ -263,6 +272,8 @@ int adf_create_ring(struct adf_accel_dev *accel_dev, const char *section,
ring->ring_size = adf_verify_ring_size(msg_size, num_msgs);
ring->head = 0;
ring->tail = 0;
+ max_inflights = ADF_MAX_INFLIGHTS(ring->ring_size, ring->msg_size);
+ ring->threshold = ADF_PERCENT(max_inflights, ADF_MAX_RING_THRESHOLD);
atomic_set(ring->inflights, 0);
ret = adf_init_ring(ring);
if (ret)
diff --git a/drivers/crypto/qat/qat_common/adf_transport.h b/drivers/crypto/qat/qat_common/adf_transport.h
index 2c95f1697c76..e6ef6f9b7691 100644
--- a/drivers/crypto/qat/qat_common/adf_transport.h
+++ b/drivers/crypto/qat/qat_common/adf_transport.h
@@ -14,6 +14,7 @@ int adf_create_ring(struct adf_accel_dev *accel_dev, const char *section,
const char *ring_name, adf_callback_fn callback,
int poll_mode, struct adf_etr_ring_data **ring_ptr);

+bool adf_ring_nearly_full(struct adf_etr_ring_data *ring);
int adf_send_message(struct adf_etr_ring_data *ring, u32 *msg);
void adf_remove_ring(struct adf_etr_ring_data *ring);
#endif
diff --git a/drivers/crypto/qat/qat_common/adf_transport_internal.h b/drivers/crypto/qat/qat_common/adf_transport_internal.h
index 501bcf0f1809..8b2c92ba7ca1 100644
--- a/drivers/crypto/qat/qat_common/adf_transport_internal.h
+++ b/drivers/crypto/qat/qat_common/adf_transport_internal.h
@@ -22,6 +22,7 @@ struct adf_etr_ring_data {
spinlock_t lock; /* protects ring data struct */
u16 head;
u16 tail;
+ u32 threshold;
u8 ring_number;
u8 ring_size;
u8 msg_size;
diff --git a/drivers/crypto/qat/qat_common/qat_algs.c b/drivers/crypto/qat/qat_common/qat_algs.c
index 6017ae82c713..873533dc43a7 100644
--- a/drivers/crypto/qat/qat_common/qat_algs.c
+++ b/drivers/crypto/qat/qat_common/qat_algs.c
@@ -935,19 +935,25 @@ void qat_alg_callback(void *resp)
struct icp_qat_fw_la_resp *qat_resp = resp;
struct qat_crypto_request *qat_req =
(void *)(__force long)qat_resp->opaque_data;
+ struct qat_instance_backlog *backlog = qat_req->alg_req.backlog;

qat_req->cb(qat_resp, qat_req);
+
+ qat_alg_send_backlog(backlog);
}

static int qat_alg_send_sym_message(struct qat_crypto_request *qat_req,
- struct qat_crypto_instance *inst)
+ struct qat_crypto_instance *inst,
+ struct crypto_async_request *base)
{
- struct qat_alg_req req;
+ struct qat_alg_req *alg_req = &qat_req->alg_req;

- req.fw_req = (u32 *)&qat_req->req;
- req.tx_ring = inst->sym_tx;
+ alg_req->fw_req = (u32 *)&qat_req->req;
+ alg_req->tx_ring = inst->sym_tx;
+ alg_req->base = base;
+ alg_req->backlog = &inst->backlog;

- return qat_alg_send_message(&req);
+ return qat_alg_send_message(alg_req);
}

static int qat_alg_aead_dec(struct aead_request *areq)
@@ -987,7 +993,7 @@ static int qat_alg_aead_dec(struct aead_request *areq)
auth_param->auth_off = 0;
auth_param->auth_len = areq->assoclen + cipher_param->cipher_length;

- ret = qat_alg_send_sym_message(qat_req, ctx->inst);
+ ret = qat_alg_send_sym_message(qat_req, ctx->inst, &areq->base);
if (ret == -ENOSPC)
qat_alg_free_bufl(ctx->inst, qat_req);

@@ -1031,7 +1037,7 @@ static int qat_alg_aead_enc(struct aead_request *areq)
auth_param->auth_off = 0;
auth_param->auth_len = areq->assoclen + areq->cryptlen;

- ret = qat_alg_send_sym_message(qat_req, ctx->inst);
+ ret = qat_alg_send_sym_message(qat_req, ctx->inst, &areq->base);
if (ret == -ENOSPC)
qat_alg_free_bufl(ctx->inst, qat_req);

@@ -1212,7 +1218,7 @@ static int qat_alg_skcipher_encrypt(struct skcipher_request *req)

qat_alg_set_req_iv(qat_req);

- ret = qat_alg_send_sym_message(qat_req, ctx->inst);
+ ret = qat_alg_send_sym_message(qat_req, ctx->inst, &req->base);
if (ret == -ENOSPC)
qat_alg_free_bufl(ctx->inst, qat_req);

@@ -1278,7 +1284,7 @@ static int qat_alg_skcipher_decrypt(struct skcipher_request *req)
qat_alg_set_req_iv(qat_req);
qat_alg_update_iv(qat_req);

- ret = qat_alg_send_sym_message(qat_req, ctx->inst);
+ ret = qat_alg_send_sym_message(qat_req, ctx->inst, &req->base);
if (ret == -ENOSPC)
qat_alg_free_bufl(ctx->inst, qat_req);

diff --git a/drivers/crypto/qat/qat_common/qat_algs_send.c b/drivers/crypto/qat/qat_common/qat_algs_send.c
index 78f1bb8c26c0..ff5b4347f783 100644
--- a/drivers/crypto/qat/qat_common/qat_algs_send.c
+++ b/drivers/crypto/qat/qat_common/qat_algs_send.c
@@ -6,7 +6,7 @@

#define ADF_MAX_RETRIES 20

-int qat_alg_send_message(struct qat_alg_req *req)
+static int qat_alg_send_message_retry(struct qat_alg_req *req)
{
int ret = 0, ctr = 0;

@@ -19,3 +19,68 @@ int qat_alg_send_message(struct qat_alg_req *req)

return -EINPROGRESS;
}
+
+void qat_alg_send_backlog(struct qat_instance_backlog *backlog)
+{
+ struct qat_alg_req *req, *tmp;
+
+ spin_lock_bh(&backlog->lock);
+ list_for_each_entry_safe(req, tmp, &backlog->list, list) {
+ if (adf_send_message(req->tx_ring, req->fw_req)) {
+ /* The HW ring is full. Do nothing.
+ * qat_alg_send_backlog() will be invoked again by
+ * another callback.
+ */
+ break;
+ }
+ list_del(&req->list);
+ req->base->complete(req->base, -EINPROGRESS);
+ }
+ spin_unlock_bh(&backlog->lock);
+}
+
+static void qat_alg_backlog_req(struct qat_alg_req *req,
+ struct qat_instance_backlog *backlog)
+{
+ INIT_LIST_HEAD(&req->list);
+
+ spin_lock_bh(&backlog->lock);
+ list_add_tail(&req->list, &backlog->list);
+ spin_unlock_bh(&backlog->lock);
+}
+
+static int qat_alg_send_message_maybacklog(struct qat_alg_req *req)
+{
+ struct qat_instance_backlog *backlog = req->backlog;
+ struct adf_etr_ring_data *tx_ring = req->tx_ring;
+ u32 *fw_req = req->fw_req;
+
+ /* If any request is already backlogged, then add to backlog list */
+ if (!list_empty(&backlog->list))
+ goto enqueue;
+
+ /* If ring is nearly full, then add to backlog list */
+ if (adf_ring_nearly_full(tx_ring))
+ goto enqueue;
+
+ /* If adding request to HW ring fails, then add to backlog list */
+ if (adf_send_message(tx_ring, fw_req))
+ goto enqueue;
+
+ return -EINPROGRESS;
+
+enqueue:
+ qat_alg_backlog_req(req, backlog);
+
+ return -EBUSY;
+}
+
+int qat_alg_send_message(struct qat_alg_req *req)
+{
+ u32 flags = req->base->flags;
+
+ if (flags & CRYPTO_TFM_REQ_MAY_BACKLOG)
+ return qat_alg_send_message_maybacklog(req);
+ else
+ return qat_alg_send_message_retry(req);
+}
diff --git a/drivers/crypto/qat/qat_common/qat_algs_send.h b/drivers/crypto/qat/qat_common/qat_algs_send.h
index 3fa685d0c293..5ce9f4f69d8f 100644
--- a/drivers/crypto/qat/qat_common/qat_algs_send.h
+++ b/drivers/crypto/qat/qat_common/qat_algs_send.h
@@ -6,5 +6,6 @@
#include "qat_crypto.h"

int qat_alg_send_message(struct qat_alg_req *req);
+void qat_alg_send_backlog(struct qat_instance_backlog *backlog);

#endif
diff --git a/drivers/crypto/qat/qat_common/qat_asym_algs.c b/drivers/crypto/qat/qat_common/qat_asym_algs.c
index 08b8d83e070a..ff7249c093c9 100644
--- a/drivers/crypto/qat/qat_common/qat_asym_algs.c
+++ b/drivers/crypto/qat/qat_common/qat_asym_algs.c
@@ -136,17 +136,21 @@ struct qat_asym_request {
} areq;
int err;
void (*cb)(struct icp_qat_fw_pke_resp *resp);
+ struct qat_alg_req alg_req;
} __aligned(64);

static int qat_alg_send_asym_message(struct qat_asym_request *qat_req,
- struct qat_crypto_instance *inst)
+ struct qat_crypto_instance *inst,
+ struct crypto_async_request *base)
{
- struct qat_alg_req req;
+ struct qat_alg_req *alg_req = &qat_req->alg_req;

- req.fw_req = (u32 *)&qat_req->req;
- req.tx_ring = inst->pke_tx;
+ alg_req->fw_req = (u32 *)&qat_req->req;
+ alg_req->tx_ring = inst->pke_tx;
+ alg_req->base = base;
+ alg_req->backlog = &inst->backlog;

- return qat_alg_send_message(&req);
+ return qat_alg_send_message(alg_req);
}

static void qat_dh_cb(struct icp_qat_fw_pke_resp *resp)
@@ -350,7 +354,7 @@ static int qat_dh_compute_value(struct kpp_request *req)
msg->input_param_count = n_input_params;
msg->output_param_count = 1;

- ret = qat_alg_send_asym_message(qat_req, ctx->inst);
+ ret = qat_alg_send_asym_message(qat_req, inst, &req->base);
if (ret == -ENOSPC)
goto unmap_all;

@@ -557,8 +561,11 @@ void qat_alg_asym_callback(void *_resp)
{
struct icp_qat_fw_pke_resp *resp = _resp;
struct qat_asym_request *areq = (void *)(__force long)resp->opaque;
+ struct qat_instance_backlog *backlog = areq->alg_req.backlog;

areq->cb(resp);
+
+ qat_alg_send_backlog(backlog);
}

#define PKE_RSA_EP_512 0x1c161b21
@@ -748,7 +755,7 @@ static int qat_rsa_enc(struct akcipher_request *req)
msg->input_param_count = 3;
msg->output_param_count = 1;

- ret = qat_alg_send_asym_message(qat_req, ctx->inst);
+ ret = qat_alg_send_asym_message(qat_req, inst, &req->base);
if (ret == -ENOSPC)
goto unmap_all;

@@ -901,7 +908,7 @@ static int qat_rsa_dec(struct akcipher_request *req)

msg->output_param_count = 1;

- ret = qat_alg_send_asym_message(qat_req, ctx->inst);
+ ret = qat_alg_send_asym_message(qat_req, inst, &req->base);
if (ret == -ENOSPC)
goto unmap_all;

diff --git a/drivers/crypto/qat/qat_common/qat_crypto.c b/drivers/crypto/qat/qat_common/qat_crypto.c
index 67c9588e89df..80d905ed102e 100644
--- a/drivers/crypto/qat/qat_common/qat_crypto.c
+++ b/drivers/crypto/qat/qat_common/qat_crypto.c
@@ -353,6 +353,9 @@ static int qat_crypto_create_instances(struct adf_accel_dev *accel_dev)
&inst->pke_rx);
if (ret)
goto err;
+
+ INIT_LIST_HEAD(&inst->backlog.list);
+ spin_lock_init(&inst->backlog.lock);
}
return 0;
err:
diff --git a/drivers/crypto/qat/qat_common/qat_crypto.h b/drivers/crypto/qat/qat_common/qat_crypto.h
index 0dcba6fc358c..245b6d9a3650 100644
--- a/drivers/crypto/qat/qat_common/qat_crypto.h
+++ b/drivers/crypto/qat/qat_common/qat_crypto.h
@@ -9,9 +9,17 @@
#include "adf_accel_devices.h"
#include "icp_qat_fw_la.h"

+struct qat_instance_backlog {
+ struct list_head list;
+ spinlock_t lock; /* protects backlog list */
+};
+
struct qat_alg_req {
u32 *fw_req;
struct adf_etr_ring_data *tx_ring;
+ struct crypto_async_request *base;
+ struct list_head list;
+ struct qat_instance_backlog *backlog;
};

struct qat_crypto_instance {
@@ -24,6 +32,7 @@ struct qat_crypto_instance {
unsigned long state;
int id;
atomic_t refctr;
+ struct qat_instance_backlog backlog;
};

#define QAT_MAX_BUFF_DESC 4
@@ -82,6 +91,7 @@ struct qat_crypto_request {
u8 iv[AES_BLOCK_SIZE];
};
bool encryption;
+ struct qat_alg_req alg_req;
};

static inline bool adf_hw_dev_has_crypto(struct adf_accel_dev *accel_dev)
--
2.35.1