3868238397
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>
87 lines
2.0 KiB
C
87 lines
2.0 KiB
C
// SPDX-License-Identifier: (BSD-3-Clause OR GPL-2.0-only)
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/* Copyright(c) 2022 Intel Corporation */
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#include "adf_transport.h"
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#include "qat_algs_send.h"
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#include "qat_crypto.h"
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#define ADF_MAX_RETRIES 20
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static int qat_alg_send_message_retry(struct qat_alg_req *req)
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{
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int ret = 0, ctr = 0;
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do {
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ret = adf_send_message(req->tx_ring, req->fw_req);
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} while (ret == -EAGAIN && ctr++ < ADF_MAX_RETRIES);
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if (ret == -EAGAIN)
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return -ENOSPC;
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return -EINPROGRESS;
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}
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void qat_alg_send_backlog(struct qat_instance_backlog *backlog)
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{
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struct qat_alg_req *req, *tmp;
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spin_lock_bh(&backlog->lock);
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list_for_each_entry_safe(req, tmp, &backlog->list, list) {
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if (adf_send_message(req->tx_ring, req->fw_req)) {
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/* The HW ring is full. Do nothing.
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* qat_alg_send_backlog() will be invoked again by
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* another callback.
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*/
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break;
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}
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list_del(&req->list);
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req->base->complete(req->base, -EINPROGRESS);
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}
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spin_unlock_bh(&backlog->lock);
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}
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static void qat_alg_backlog_req(struct qat_alg_req *req,
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struct qat_instance_backlog *backlog)
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{
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INIT_LIST_HEAD(&req->list);
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spin_lock_bh(&backlog->lock);
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list_add_tail(&req->list, &backlog->list);
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spin_unlock_bh(&backlog->lock);
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}
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static int qat_alg_send_message_maybacklog(struct qat_alg_req *req)
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{
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struct qat_instance_backlog *backlog = req->backlog;
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struct adf_etr_ring_data *tx_ring = req->tx_ring;
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u32 *fw_req = req->fw_req;
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/* If any request is already backlogged, then add to backlog list */
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if (!list_empty(&backlog->list))
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goto enqueue;
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/* If ring is nearly full, then add to backlog list */
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if (adf_ring_nearly_full(tx_ring))
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goto enqueue;
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/* If adding request to HW ring fails, then add to backlog list */
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if (adf_send_message(tx_ring, fw_req))
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goto enqueue;
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return -EINPROGRESS;
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enqueue:
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qat_alg_backlog_req(req, backlog);
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return -EBUSY;
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}
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int qat_alg_send_message(struct qat_alg_req *req)
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{
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u32 flags = req->base->flags;
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if (flags & CRYPTO_TFM_REQ_MAY_BACKLOG)
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return qat_alg_send_message_maybacklog(req);
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else
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return qat_alg_send_message_retry(req);
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}
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