Commit 4363f3d3 authored by Harman Kalra's avatar Harman Kalra Committed by Herbert Xu
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crypto: octeontx2 - add synchronization between mailbox accesses 



Since there are two workqueues implemented in CPTPF driver - one
for handling mailbox requests from VFs and another for handling FLR.
In both cases PF driver will forward the request to AF driver by
writing to mailbox memory. A race condition may arise if two
simultaneous requests are written to mailbox memory. Introducing
locking mechanism to maintain synchronization between multiple
mailbox accesses.

Signed-off-by: default avatarHarman Kalra <hkalra@marvell.com>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent 82082856

drivers/crypto/marvell/octeontx2/otx2_cpt_common.h

+1 −0
Original line number Diff line number Diff line
@@ -157,5 +157,6 @@ struct otx2_cptlfs_info; 
int otx2_cpt_attach_rscrs_msg(struct otx2_cptlfs_info *lfs);

int otx2_cpt_detach_rsrcs_msg(struct otx2_cptlfs_info *lfs);

int otx2_cpt_msix_offset_msg(struct otx2_cptlfs_info *lfs);

int otx2_cpt_sync_mbox_msg(struct otx2_mbox *mbox);



#endif /* __OTX2_CPT_COMMON_H */

drivers/crypto/marvell/octeontx2/otx2_cpt_mbox_common.c

+14 −0
Original line number Diff line number Diff line
@@ -202,3 +202,17 @@ int otx2_cpt_msix_offset_msg(struct otx2_cptlfs_info *lfs) 
	}

	return ret;

}



int otx2_cpt_sync_mbox_msg(struct otx2_mbox *mbox)

{

	int err;



	if (!otx2_mbox_nonempty(mbox, 0))

		return 0;

	otx2_mbox_msg_send(mbox, 0);

	err = otx2_mbox_wait_for_rsp(mbox, 0);

	if (err)

		return err;



	return otx2_mbox_check_rsp_msgs(mbox, 0);

}

drivers/crypto/marvell/octeontx2/otx2_cptpf.h

+1 −0
Original line number Diff line number Diff line
@@ -46,6 +46,7 @@ struct otx2_cptpf_dev { 


	struct workqueue_struct	*flr_wq;

	struct cptpf_flr_work   *flr_work;

	struct mutex            lock;   /* serialize mailbox access */



	unsigned long cap_flag;

	u8 pf_id;               /* RVU PF number */

drivers/crypto/marvell/octeontx2/otx2_cptpf_main.c

+13 −8
Original line number Diff line number Diff line
@@ -140,6 +140,7 @@ static void cptpf_flr_wq_handler(struct work_struct *work) 


	vf = flr_work - pf->flr_work;



	mutex_lock(&pf->lock);

	req = otx2_mbox_alloc_msg_rsp(mbox, 0, sizeof(*req),

				      sizeof(struct msg_rsp));

	if (!req)
@@ -151,6 +152,7 @@ static void cptpf_flr_wq_handler(struct work_struct *work) 
	req->pcifunc |= (vf + 1) & RVU_PFVF_FUNC_MASK;



	otx2_cpt_send_mbox_msg(mbox, pf->pdev);

	if (!otx2_cpt_sync_mbox_msg(&pf->afpf_mbox)) {



		if (vf >= 64) {

			reg = 1;
@@ -162,6 +164,8 @@ static void cptpf_flr_wq_handler(struct work_struct *work) 
		otx2_cpt_write64(pf->reg_base, BLKADDR_RVUM, 0,

				 RVU_PF_VFFLR_INT_ENA_W1SX(reg), BIT_ULL(vf));

	}

	mutex_unlock(&pf->lock);

}



static irqreturn_t cptpf_vf_flr_intr(int __always_unused irq, void *arg)

{
@@ -468,6 +472,7 @@ static int cptpf_afpf_mbox_init(struct otx2_cptpf_dev *cptpf) 
		goto error;



	INIT_WORK(&cptpf->afpf_mbox_work, otx2_cptpf_afpf_mbox_handler);

	mutex_init(&cptpf->lock);

	return 0;



error:

drivers/crypto/marvell/octeontx2/otx2_cptpf_mbox.c

+17 −6
Original line number Diff line number Diff line
@@ -18,6 +18,7 @@ static int forward_to_af(struct otx2_cptpf_dev *cptpf, 
	struct mbox_msghdr *msg;

	int ret;



	mutex_lock(&cptpf->lock);

	msg = otx2_mbox_alloc_msg(&cptpf->afpf_mbox, 0, size);

	if (msg == NULL)

		return -ENOMEM;
@@ -29,15 +30,19 @@ static int forward_to_af(struct otx2_cptpf_dev *cptpf, 
	msg->sig = req->sig;

	msg->ver = req->ver;



	otx2_mbox_msg_send(&cptpf->afpf_mbox, 0);

	ret = otx2_mbox_wait_for_rsp(&cptpf->afpf_mbox, 0);

	ret = otx2_cpt_sync_mbox_msg(&cptpf->afpf_mbox);

	/* Error code -EIO indicate there is a communication failure

	 * to the AF. Rest of the error codes indicate that AF processed

	 * VF messages and set the error codes in response messages

	 * (if any) so simply forward responses to VF.

	 */

	if (ret == -EIO) {

		dev_err(&cptpf->pdev->dev, "RVU MBOX timeout.\n");

		dev_warn(&cptpf->pdev->dev,

			 "AF not responding to VF%d messages\n", vf->vf_id);

		mutex_unlock(&cptpf->lock);

		return ret;

	} else if (ret) {

		dev_err(&cptpf->pdev->dev, "RVU MBOX error: %d.\n", ret);

		return -EFAULT;

	}

	mutex_unlock(&cptpf->lock);

	return 0;

}
@@ -204,6 +209,10 @@ void otx2_cptpf_vfpf_mbox_handler(struct work_struct *work) 
		if (err == -ENOMEM || err == -EIO)

			break;

		offset = msg->next_msgoff;

		/* Write barrier required for VF responses which are handled by

		 * PF driver and not forwarded to AF.

		 */

		smp_wmb();

	}

	/* Send mbox responses to VF */

	if (mdev->num_msgs)
@@ -350,6 +359,8 @@ void otx2_cptpf_afpf_mbox_handler(struct work_struct *work) 
			process_afpf_mbox_msg(cptpf, msg);



		offset = msg->next_msgoff;

		/* Sync VF response ready to be sent */

		smp_wmb();

		mdev->msgs_acked++;

	}

	otx2_mbox_reset(afpf_mbox, 0);