RDMA/qedr: Add doorbell overflow recovery support

Use the doorbell recovery mechanism to register rdma related doorbells
that will be restored in case there is a doorbell overflow attention.

Link: https://lore.kernel.org/r/20191030094417.16866-8-michal.kalderon@marvell.comSigned-off-by: Ariel Elior <ariel.elior@marvell.com>
Signed-off-by: Michal Kalderon <michal.kalderon@marvell.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/hw/qedr/qedr.h

@@ -235,6 +235,7 @@ struct qedr_ucontext {
 	u64 dpi_phys_addr;
 	u32 dpi_size;
 	u16 dpi;
+	bool db_rec;
 };
 
 union db_prod64 {
@@ -262,6 +263,11 @@ struct qedr_userq {
 	struct qedr_pbl *pbl_tbl;
 	u64 buf_addr;
 	size_t buf_len;
+
+	/* doorbell recovery */
+	void __iomem *db_addr;
+	struct qedr_user_db_rec *db_rec_data;
+	struct rdma_user_mmap_entry *db_mmap_entry;
 };
 
 struct qedr_cq {
@@ -482,7 +488,10 @@ struct qedr_mr {
 struct qedr_user_mmap_entry {
 	struct rdma_user_mmap_entry rdma_entry;
 	struct qedr_dev *dev;
-	u64 io_address;
+	union {
+		u64 io_address;
+		void *address;
+	};
 	size_t length;
 	u16 dpi;
 	u8 mmap_flag;

drivers/infiniband/hw/qedr/verbs.c

@@ -61,6 +61,7 @@
 
 enum {
 	QEDR_USER_MMAP_IO_WC = 0,
+	QEDR_USER_MMAP_PHYS_PAGE,
 };
 
 static inline int qedr_ib_copy_to_udata(struct ib_udata *udata, void *src,
@@ -267,6 +268,7 @@ int qedr_alloc_ucontext(struct ib_ucontext *uctx, struct ib_udata *udata)
 	int rc;
 	struct qedr_ucontext *ctx = get_qedr_ucontext(uctx);
 	struct qedr_alloc_ucontext_resp uresp = {};
+	struct qedr_alloc_ucontext_req ureq = {};
 	struct qedr_dev *dev = get_qedr_dev(ibdev);
 	struct qed_rdma_add_user_out_params oparams;
 	struct qedr_user_mmap_entry *entry;
@@ -274,6 +276,17 @@ int qedr_alloc_ucontext(struct ib_ucontext *uctx, struct ib_udata *udata)
 	if (!udata)
 		return -EFAULT;
 
+	if (udata->inlen) {
+		rc = ib_copy_from_udata(&ureq, udata,
+					min(sizeof(ureq), udata->inlen));
+		if (rc) {
+			DP_ERR(dev, "Problem copying data from user space\n");
+			return -EFAULT;
+		}
+
+		ctx->db_rec = !!(ureq.context_flags & QEDR_ALLOC_UCTX_DB_REC);
+	}
+
 	rc = dev->ops->rdma_add_user(dev->rdma_ctx, &oparams);
 	if (rc) {
 		DP_ERR(dev,
@@ -352,7 +365,9 @@ void qedr_mmap_free(struct rdma_user_mmap_entry *rdma_entry)
 	struct qedr_user_mmap_entry *entry = get_qedr_mmap_entry(rdma_entry);
 	struct qedr_dev *dev = entry->dev;
 
-	if (entry->mmap_flag == QEDR_USER_MMAP_IO_WC)
+	if (entry->mmap_flag == QEDR_USER_MMAP_PHYS_PAGE)
+		free_page((unsigned long)entry->address);
+	else if (entry->mmap_flag == QEDR_USER_MMAP_IO_WC)
 		dev->ops->rdma_remove_user(dev->rdma_ctx, entry->dpi);
 
 	kfree(entry);
@@ -389,6 +404,10 @@ int qedr_mmap(struct ib_ucontext *ucontext, struct vm_area_struct *vma)
 				       pgprot_writecombine(vma->vm_page_prot),
 				       rdma_entry);
 		break;
+	case QEDR_USER_MMAP_PHYS_PAGE:
+		rc = vm_insert_page(vma, vma->vm_start,
+				    virt_to_page(entry->address));
+		break;
 	default:
 		rc = -EINVAL;
 	}
@@ -629,16 +648,48 @@ static void qedr_populate_pbls(struct qedr_dev *dev, struct ib_umem *umem,
 	}
 }
 
+static int qedr_db_recovery_add(struct qedr_dev *dev,
+				void __iomem *db_addr,
+				void *db_data,
+				enum qed_db_rec_width db_width,
+				enum qed_db_rec_space db_space)
+{
+	if (!db_data) {
+		DP_DEBUG(dev, QEDR_MSG_INIT, "avoiding db rec since old lib\n");
+		return 0;
+	}
+
+	return dev->ops->common->db_recovery_add(dev->cdev, db_addr, db_data,
+						 db_width, db_space);
+}
+
+static void qedr_db_recovery_del(struct qedr_dev *dev,
+				 void __iomem *db_addr,
+				 void *db_data)
+{
+	if (!db_data) {
+		DP_DEBUG(dev, QEDR_MSG_INIT, "avoiding db rec since old lib\n");
+		return;
+	}
+
+	/* Ignore return code as there is not much we can do about it. Error
+	 * log will be printed inside.
+	 */
+	dev->ops->common->db_recovery_del(dev->cdev, db_addr, db_data);
+}
+
 static int qedr_copy_cq_uresp(struct qedr_dev *dev,
-			      struct qedr_cq *cq, struct ib_udata *udata)
+			      struct qedr_cq *cq, struct ib_udata *udata,
+			      u32 db_offset)
 {
 	struct qedr_create_cq_uresp uresp;
 	int rc;
 
 	memset(&uresp, 0, sizeof(uresp));
 
-	uresp.db_offset = DB_ADDR_SHIFT(DQ_PWM_OFFSET_UCM_RDMA_CQ_CONS_32BIT);
+	uresp.db_offset = db_offset;
 	uresp.icid = cq->icid;
+	uresp.db_rec_addr = rdma_user_mmap_get_offset(cq->q.db_mmap_entry);
 
 	rc = qedr_ib_copy_to_udata(udata, &uresp, sizeof(uresp));
 	if (rc)
@@ -666,10 +717,58 @@ static inline int qedr_align_cq_entries(int entries)
 	return aligned_size / QEDR_CQE_SIZE;
 }
 
+static int qedr_init_user_db_rec(struct ib_udata *udata,
+				 struct qedr_dev *dev, struct qedr_userq *q,
+				 bool requires_db_rec)
+{
+	struct qedr_ucontext *uctx =
+		rdma_udata_to_drv_context(udata, struct qedr_ucontext,
+					  ibucontext);
+	struct qedr_user_mmap_entry *entry;
+	int rc;
+
+	/* Aborting for non doorbell userqueue (SRQ) or non-supporting lib */
+	if (requires_db_rec == 0 || !uctx->db_rec)
+		return 0;
+
+	/* Allocate a page for doorbell recovery, add to mmap */
+	q->db_rec_data = (void *)get_zeroed_page(GFP_USER);
+	if (!q->db_rec_data) {
+		DP_ERR(dev, "get_zeroed_page failed\n");
+		return -ENOMEM;
+	}
+
+	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+	if (!entry)
+		goto err_free_db_data;
+
+	entry->address = q->db_rec_data;
+	entry->length = PAGE_SIZE;
+	entry->mmap_flag = QEDR_USER_MMAP_PHYS_PAGE;
+	rc = rdma_user_mmap_entry_insert(&uctx->ibucontext,
+					 &entry->rdma_entry,
+					 PAGE_SIZE);
+	if (rc)
+		goto err_free_entry;
+
+	q->db_mmap_entry = &entry->rdma_entry;
+
+	return 0;
+
+err_free_entry:
+	kfree(entry);
+
+err_free_db_data:
+	free_page((unsigned long)q->db_rec_data);
+	q->db_rec_data = NULL;
+	return -ENOMEM;
+}
+
 static inline int qedr_init_user_queue(struct ib_udata *udata,
 				       struct qedr_dev *dev,
 				       struct qedr_userq *q, u64 buf_addr,
-				       size_t buf_len, int access, int dmasync,
+				       size_t buf_len, bool requires_db_rec,
+				       int access, int dmasync,
 				       int alloc_and_init)
 {
 	u32 fw_pages;
@@ -707,7 +806,8 @@ static inline int qedr_init_user_queue(struct ib_udata *udata,
 		}
 	}
 
-	return 0;
+	/* mmap the user address used to store doorbell data for recovery */
+	return qedr_init_user_db_rec(udata, dev, q, requires_db_rec);
 
 err0:
 	ib_umem_release(q->umem);
@@ -793,6 +893,7 @@ int qedr_create_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr,
 	int entries = attr->cqe;
 	struct qedr_cq *cq = get_qedr_cq(ibcq);
 	int chain_entries;
+	u32 db_offset;
 	int page_cnt;
 	u64 pbl_ptr;
 	u16 icid;
@@ -812,8 +913,12 @@ int qedr_create_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr,
 	chain_entries = qedr_align_cq_entries(entries);
 	chain_entries = min_t(int, chain_entries, QEDR_MAX_CQES);
 
+	/* calc db offset. user will add DPI base, kernel will add db addr */
+	db_offset = DB_ADDR_SHIFT(DQ_PWM_OFFSET_UCM_RDMA_CQ_CONS_32BIT);
+
 	if (udata) {
-		if (ib_copy_from_udata(&ureq, udata, sizeof(ureq))) {
+		if (ib_copy_from_udata(&ureq, udata, min(sizeof(ureq),
+							 udata->inlen))) {
 			DP_ERR(dev,
 			       "create cq: problem copying data from user space\n");
 			goto err0;
@@ -828,8 +933,9 @@ int qedr_create_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr,
 		cq->cq_type = QEDR_CQ_TYPE_USER;
 
 		rc = qedr_init_user_queue(udata, dev, &cq->q, ureq.addr,
-					  ureq.len, IB_ACCESS_LOCAL_WRITE, 1,
-					  1);
+					  ureq.len, true,
+					  IB_ACCESS_LOCAL_WRITE,
+					  1, 1);
 		if (rc)
 			goto err0;
 
@@ -837,6 +943,7 @@ int qedr_create_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr,
 		page_cnt = cq->q.pbl_info.num_pbes;
 
 		cq->ibcq.cqe = chain_entries;
+		cq->q.db_addr = ctx->dpi_addr + db_offset;
 	} else {
 		cq->cq_type = QEDR_CQ_TYPE_KERNEL;
 
@@ -848,7 +955,7 @@ int qedr_create_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr,
 						   sizeof(union rdma_cqe),
 						   &cq->pbl, NULL);
 		if (rc)
-			goto err1;
+			goto err0;
 
 		page_cnt = qed_chain_get_page_cnt(&cq->pbl);
 		pbl_ptr = qed_chain_get_pbl_phys(&cq->pbl);
@@ -860,21 +967,28 @@ int qedr_create_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr,
 
 	rc = dev->ops->rdma_create_cq(dev->rdma_ctx, &params, &icid);
 	if (rc)
-		goto err2;
+		goto err1;
 
 	cq->icid = icid;
 	cq->sig = QEDR_CQ_MAGIC_NUMBER;
 	spin_lock_init(&cq->cq_lock);
 
 	if (udata) {
-		rc = qedr_copy_cq_uresp(dev, cq, udata);
+		rc = qedr_copy_cq_uresp(dev, cq, udata, db_offset);
 		if (rc)
-			goto err3;
+			goto err2;
+
+		rc = qedr_db_recovery_add(dev, cq->q.db_addr,
+					  &cq->q.db_rec_data->db_data,
+					  DB_REC_WIDTH_64B,
+					  DB_REC_USER);
+		if (rc)
+			goto err2;
+
 	} else {
 		/* Generate doorbell address. */
-		cq->db_addr = dev->db_addr +
-		    DB_ADDR_SHIFT(DQ_PWM_OFFSET_UCM_RDMA_CQ_CONS_32BIT);
 		cq->db.data.icid = cq->icid;
+		cq->db_addr = dev->db_addr + db_offset;
 		cq->db.data.params = DB_AGG_CMD_SET <<
 		    RDMA_PWM_VAL32_DATA_AGG_CMD_SHIFT;
 
@@ -884,6 +998,11 @@ int qedr_create_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr,
 		cq->latest_cqe = NULL;
 		consume_cqe(cq);
 		cq->cq_cons = qed_chain_get_cons_idx_u32(&cq->pbl);
+
+		rc = qedr_db_recovery_add(dev, cq->db_addr, &cq->db.data,
+					  DB_REC_WIDTH_64B, DB_REC_KERNEL);
+		if (rc)
+			goto err2;
 	}
 
 	DP_DEBUG(dev, QEDR_MSG_CQ,
@@ -892,18 +1011,19 @@ int qedr_create_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr,
 
 	return 0;
 
-err3:
+err2:
 	destroy_iparams.icid = cq->icid;
 	dev->ops->rdma_destroy_cq(dev->rdma_ctx, &destroy_iparams,
 				  &destroy_oparams);
-err2:
-	if (udata)
-		qedr_free_pbl(dev, &cq->q.pbl_info, cq->q.pbl_tbl);
-	else
-		dev->ops->common->chain_free(dev->cdev, &cq->pbl);
 err1:
-	if (udata)
+	if (udata) {
+		qedr_free_pbl(dev, &cq->q.pbl_info, cq->q.pbl_tbl);
 		ib_umem_release(cq->q.umem);
+		if (ctx)
+			rdma_user_mmap_entry_remove(cq->q.db_mmap_entry);
+	} else {
+		dev->ops->common->chain_free(dev->cdev, &cq->pbl);
+	}
 err0:
 	return -EINVAL;
 }
@@ -934,8 +1054,10 @@ void qedr_destroy_cq(struct ib_cq *ibcq, struct ib_udata *udata)
 	cq->destroyed = 1;
 
 	/* GSIs CQs are handled by driver, so they don't exist in the FW */
-	if (cq->cq_type == QEDR_CQ_TYPE_GSI)
+	if (cq->cq_type == QEDR_CQ_TYPE_GSI) {
+		qedr_db_recovery_del(dev, cq->db_addr, &cq->db.data);
 		return;
+	}
 
 	iparams.icid = cq->icid;
 	dev->ops->rdma_destroy_cq(dev->rdma_ctx, &iparams, &oparams);
@@ -944,6 +1066,14 @@ void qedr_destroy_cq(struct ib_cq *ibcq, struct ib_udata *udata)
 	if (udata) {
 		qedr_free_pbl(dev, &cq->q.pbl_info, cq->q.pbl_tbl);
 		ib_umem_release(cq->q.umem);
+
+		if (cq->q.db_rec_data) {
+			qedr_db_recovery_del(dev, cq->q.db_addr,
+					     &cq->q.db_rec_data->db_data);
+			rdma_user_mmap_entry_remove(cq->q.db_mmap_entry);
+		}
+	} else {
+		qedr_db_recovery_del(dev, cq->db_addr, &cq->db.data);
 	}
 
 	/* We don't want the IRQ handler to handle a non-existing CQ so we
@@ -1108,8 +1238,8 @@ static int qedr_copy_srq_uresp(struct qedr_dev *dev,
 }
 
 static void qedr_copy_rq_uresp(struct qedr_dev *dev,
-			       struct qedr_create_qp_uresp *uresp,
-			       struct qedr_qp *qp)
+			      struct qedr_create_qp_uresp *uresp,
+			      struct qedr_qp *qp)
 {
 	/* iWARP requires two doorbells per RQ. */
 	if (rdma_protocol_iwarp(&dev->ibdev, 1)) {
@@ -1122,6 +1252,7 @@ static void qedr_copy_rq_uresp(struct qedr_dev *dev,
 	}
 
 	uresp->rq_icid = qp->icid;
+	uresp->rq_db_rec_addr = rdma_user_mmap_get_offset(qp->urq.db_mmap_entry);
 }
 
 static void qedr_copy_sq_uresp(struct qedr_dev *dev,
@@ -1135,22 +1266,25 @@ static void qedr_copy_sq_uresp(struct qedr_dev *dev,
 		uresp->sq_icid = qp->icid;
 	else
 		uresp->sq_icid = qp->icid + 1;
+
+	uresp->sq_db_rec_addr =
+		rdma_user_mmap_get_offset(qp->usq.db_mmap_entry);
 }
 
 static int qedr_copy_qp_uresp(struct qedr_dev *dev,
-			      struct qedr_qp *qp, struct ib_udata *udata)
+			      struct qedr_qp *qp, struct ib_udata *udata,
+			      struct qedr_create_qp_uresp *uresp)
 {
-	struct qedr_create_qp_uresp uresp;
 	int rc;
 
-	memset(&uresp, 0, sizeof(uresp));
-	qedr_copy_sq_uresp(dev, &uresp, qp);
-	qedr_copy_rq_uresp(dev, &uresp, qp);
+	memset(uresp, 0, sizeof(*uresp));
+	qedr_copy_sq_uresp(dev, uresp, qp);
+	qedr_copy_rq_uresp(dev, uresp, qp);
 
-	uresp.atomic_supported = dev->atomic_cap != IB_ATOMIC_NONE;
-	uresp.qp_id = qp->qp_id;
+	uresp->atomic_supported = dev->atomic_cap != IB_ATOMIC_NONE;
+	uresp->qp_id = qp->qp_id;
 
-	rc = qedr_ib_copy_to_udata(udata, &uresp, sizeof(uresp));
+	rc = qedr_ib_copy_to_udata(udata, uresp, sizeof(*uresp));
 	if (rc)
 		DP_ERR(dev,
 		       "create qp: failed a copy to user space with qp icid=0x%x.\n",
@@ -1197,16 +1331,35 @@ static void qedr_set_common_qp_params(struct qedr_dev *dev,
 		 qp->sq.max_sges, qp->sq_cq->icid);
 }
 
-static void qedr_set_roce_db_info(struct qedr_dev *dev, struct qedr_qp *qp)
+static int qedr_set_roce_db_info(struct qedr_dev *dev, struct qedr_qp *qp)
 {
+	int rc;
+
 	qp->sq.db = dev->db_addr +
 		    DB_ADDR_SHIFT(DQ_PWM_OFFSET_XCM_RDMA_SQ_PROD);
 	qp->sq.db_data.data.icid = qp->icid + 1;
+	rc = qedr_db_recovery_add(dev, qp->sq.db,
+				  &qp->sq.db_data,
+				  DB_REC_WIDTH_32B,
+				  DB_REC_KERNEL);
+	if (rc)
+		return rc;
+
 	if (!qp->srq) {
 		qp->rq.db = dev->db_addr +
 			    DB_ADDR_SHIFT(DQ_PWM_OFFSET_TCM_ROCE_RQ_PROD);
 		qp->rq.db_data.data.icid = qp->icid;
+
+		rc = qedr_db_recovery_add(dev, qp->rq.db,
+					  &qp->rq.db_data,
+					  DB_REC_WIDTH_32B,
+					  DB_REC_KERNEL);
+		if (rc)
+			qedr_db_recovery_del(dev, qp->sq.db,
+					     &qp->sq.db_data);
 	}
+
+	return rc;
 }
 
 static int qedr_check_srq_params(struct qedr_dev *dev,
@@ -1260,7 +1413,7 @@ static int qedr_init_srq_user_params(struct ib_udata *udata,
 	int rc;
 
 	rc = qedr_init_user_queue(udata, srq->dev, &srq->usrq, ureq->srq_addr,
-				  ureq->srq_len, access, dmasync, 1);
+				  ureq->srq_len, false, access, dmasync, 1);
 	if (rc)
 		return rc;
 
@@ -1356,7 +1509,8 @@ int qedr_create_srq(struct ib_srq *ibsrq, struct ib_srq_init_attr *init_attr,
 	hw_srq->max_sges = init_attr->attr.max_sge;
 
 	if (udata) {
-		if (ib_copy_from_udata(&ureq, udata, sizeof(ureq))) {
+		if (ib_copy_from_udata(&ureq, udata, min(sizeof(ureq),
+							 udata->inlen))) {
 			DP_ERR(dev,
 			       "create srq: problem copying data from user space\n");
 			goto err0;
@@ -1545,7 +1699,9 @@ qedr_iwarp_populate_user_qp(struct qedr_dev *dev,
 			   &qp->urq.pbl_info, FW_PAGE_SHIFT);
 }
 
-static void qedr_cleanup_user(struct qedr_dev *dev, struct qedr_qp *qp)
+static void qedr_cleanup_user(struct qedr_dev *dev,
+			      struct qedr_ucontext *ctx,
+			      struct qedr_qp *qp)
 {
 	ib_umem_release(qp->usq.umem);
 	qp->usq.umem = NULL;
@@ -1560,6 +1716,18 @@ static void qedr_cleanup_user(struct qedr_dev *dev, struct qedr_qp *qp)
 		kfree(qp->usq.pbl_tbl);
 		kfree(qp->urq.pbl_tbl);
 	}
+
+	if (qp->usq.db_rec_data) {
+		qedr_db_recovery_del(dev, qp->usq.db_addr,
+				     &qp->usq.db_rec_data->db_data);
+		rdma_user_mmap_entry_remove(qp->usq.db_mmap_entry);
+	}
+
+	if (qp->urq.db_rec_data) {
+		qedr_db_recovery_del(dev, qp->urq.db_addr,
+				     &qp->urq.db_rec_data->db_data);
+		rdma_user_mmap_entry_remove(qp->urq.db_mmap_entry);
+	}
 }
 
 static int qedr_create_user_qp(struct qedr_dev *dev,
@@ -1571,13 +1739,15 @@ static int qedr_create_user_qp(struct qedr_dev *dev,
 	struct qed_rdma_create_qp_in_params in_params;
 	struct qed_rdma_create_qp_out_params out_params;
 	struct qedr_pd *pd = get_qedr_pd(ibpd);
+	struct qedr_create_qp_uresp uresp;
+	struct qedr_ucontext *ctx = NULL;
 	struct qedr_create_qp_ureq ureq;
 	int alloc_and_init = rdma_protocol_roce(&dev->ibdev, 1);
 	int rc = -EINVAL;
 
 	qp->create_type = QEDR_QP_CREATE_USER;
 	memset(&ureq, 0, sizeof(ureq));
-	rc = ib_copy_from_udata(&ureq, udata, sizeof(ureq));
+	rc = ib_copy_from_udata(&ureq, udata, min(sizeof(ureq), udata->inlen));
 	if (rc) {
 		DP_ERR(dev, "Problem copying data from user space\n");
 		return rc;
@@ -1585,14 +1755,16 @@ static int qedr_create_user_qp(struct qedr_dev *dev,
 
 	/* SQ - read access only (0), dma sync not required (0) */
 	rc = qedr_init_user_queue(udata, dev, &qp->usq, ureq.sq_addr,
-				  ureq.sq_len, 0, 0, alloc_and_init);
+				  ureq.sq_len, true, 0, 0,
+				  alloc_and_init);
 	if (rc)
 		return rc;
 
 	if (!qp->srq) {
 		/* RQ - read access only (0), dma sync not required (0) */
 		rc = qedr_init_user_queue(udata, dev, &qp->urq, ureq.rq_addr,
-					  ureq.rq_len, 0, 0, alloc_and_init);
+					  ureq.rq_len, true,
+					  0, 0, alloc_and_init);
 		if (rc)
 			return rc;
 	}
@@ -1622,29 +1794,57 @@ static int qedr_create_user_qp(struct qedr_dev *dev,
 	qp->qp_id = out_params.qp_id;
 	qp->icid = out_params.icid;
 
-	rc = qedr_copy_qp_uresp(dev, qp, udata);
+	rc = qedr_copy_qp_uresp(dev, qp, udata, &uresp);
+	if (rc)
+		goto err;
+
+	/* db offset was calculated in copy_qp_uresp, now set in the user q */
+	ctx = pd->uctx;
+	qp->usq.db_addr = ctx->dpi_addr + uresp.sq_db_offset;
+	qp->urq.db_addr = ctx->dpi_addr + uresp.rq_db_offset;
+
+	rc = qedr_db_recovery_add(dev, qp->usq.db_addr,
+				  &qp->usq.db_rec_data->db_data,
+				  DB_REC_WIDTH_32B,
+				  DB_REC_USER);
+	if (rc)
+		goto err;
+
+	rc = qedr_db_recovery_add(dev, qp->urq.db_addr,
+				  &qp->urq.db_rec_data->db_data,
+				  DB_REC_WIDTH_32B,
+				  DB_REC_USER);
 	if (rc)
 		goto err;
 
 	qedr_qp_user_print(dev, qp);
 
-	return 0;
+	return rc;
 err:
 	rc = dev->ops->rdma_destroy_qp(dev->rdma_ctx, qp->qed_qp);
 	if (rc)
 		DP_ERR(dev, "create qp: fatal fault. rc=%d", rc);
 
 err1:
-	qedr_cleanup_user(dev, qp);
+	qedr_cleanup_user(dev, ctx, qp);
 	return rc;
 }
 
-static void qedr_set_iwarp_db_info(struct qedr_dev *dev, struct qedr_qp *qp)
+static int qedr_set_iwarp_db_info(struct qedr_dev *dev, struct qedr_qp *qp)
 {
+	int rc;
+
 	qp->sq.db = dev->db_addr +
 	    DB_ADDR_SHIFT(DQ_PWM_OFFSET_XCM_RDMA_SQ_PROD);
 	qp->sq.db_data.data.icid = qp->icid;
 
+	rc = qedr_db_recovery_add(dev, qp->sq.db,
+				  &qp->sq.db_data,
+				  DB_REC_WIDTH_32B,
+				  DB_REC_KERNEL);
+	if (rc)
+		return rc;
+
 	qp->rq.db = dev->db_addr +
 		    DB_ADDR_SHIFT(DQ_PWM_OFFSET_TCM_IWARP_RQ_PROD);
 	qp->rq.db_data.data.icid = qp->icid;
@@ -1652,6 +1852,12 @@ static void qedr_set_iwarp_db_info(struct qedr_dev *dev, struct qedr_qp *qp)
 			   DB_ADDR_SHIFT(DQ_PWM_OFFSET_TCM_FLAGS);
 	qp->rq.iwarp_db2_data.data.icid = qp->icid;
 	qp->rq.iwarp_db2_data.data.value = DQ_TCM_IWARP_POST_RQ_CF_CMD;
+
+	rc = qedr_db_recovery_add(dev, qp->rq.db,
+				  &qp->rq.db_data,
+				  DB_REC_WIDTH_32B,
+				  DB_REC_KERNEL);
+	return rc;
 }
 
 static int
@@ -1699,8 +1905,7 @@ qedr_roce_create_kernel_qp(struct qedr_dev *dev,
 	qp->qp_id = out_params.qp_id;
 	qp->icid = out_params.icid;
 
-	qedr_set_roce_db_info(dev, qp);
-	return rc;
+	return qedr_set_roce_db_info(dev, qp);
 }
 
 static int
@@ -1758,8 +1963,7 @@ qedr_iwarp_create_kernel_qp(struct qedr_dev *dev,
 	qp->qp_id = out_params.qp_id;
 	qp->icid = out_params.icid;
 
-	qedr_set_iwarp_db_info(dev, qp);
-	return rc;
+	return qedr_set_iwarp_db_info(dev, qp);
 
 err:
 	dev->ops->rdma_destroy_qp(dev->rdma_ctx, qp->qed_qp);
@@ -1774,6 +1978,15 @@ static void qedr_cleanup_kernel(struct qedr_dev *dev, struct qedr_qp *qp)
 
 	dev->ops->common->chain_free(dev->cdev, &qp->rq.pbl);
 	kfree(qp->rqe_wr_id);
+
+	/* GSI qp is not registered to db mechanism so no need to delete */
+	if (qp->qp_type == IB_QPT_GSI)
+		return;
+
+	qedr_db_recovery_del(dev, qp->sq.db, &qp->sq.db_data);
+
+	if (!qp->srq)
+		qedr_db_recovery_del(dev, qp->rq.db, &qp->rq.db_data);
 }
 
 static int qedr_create_kernel_qp(struct qedr_dev *dev,
@@ -2414,7 +2627,10 @@ int qedr_query_qp(struct ib_qp *ibqp,
 static int qedr_free_qp_resources(struct qedr_dev *dev, struct qedr_qp *qp,
 				  struct ib_udata *udata)
 {
-	int rc = 0;
+	struct qedr_ucontext *ctx =
+		rdma_udata_to_drv_context(udata, struct qedr_ucontext,
+					  ibucontext);
+	int rc;
 
 	if (qp->qp_type != IB_QPT_GSI) {
 		rc = dev->ops->rdma_destroy_qp(dev->rdma_ctx, qp->qed_qp);
@@ -2423,7 +2639,7 @@ static int qedr_free_qp_resources(struct qedr_dev *dev, struct qedr_qp *qp,
 	}
 
 	if (qp->create_type == QEDR_QP_CREATE_USER)
-		qedr_cleanup_user(dev, qp);
+		qedr_cleanup_user(dev, ctx, qp);
 	else
 		qedr_cleanup_kernel(dev, qp);
 

include/uapi/rdma/qedr-abi.h

@@ -38,6 +38,15 @@
 #define QEDR_ABI_VERSION		(8)
 
 /* user kernel communication data structures. */
+enum qedr_alloc_ucontext_flags {
+	QEDR_ALLOC_UCTX_RESERVED	= 1 << 0,
+	QEDR_ALLOC_UCTX_DB_REC		= 1 << 1
+};
+
+struct qedr_alloc_ucontext_req {
+	__u32 context_flags;
+	__u32 reserved;
+};
 
 struct qedr_alloc_ucontext_resp {
 	__aligned_u64 db_pa;
@@ -74,6 +83,7 @@ struct qedr_create_cq_uresp {
 	__u32 db_offset;
 	__u16 icid;
 	__u16 reserved;
+	__aligned_u64 db_rec_addr;
 };
 
 struct qedr_create_qp_ureq {
@@ -109,6 +119,13 @@ struct qedr_create_qp_uresp {
 
 	__u32 rq_db2_offset;
 	__u32 reserved;
+
+	/* address of SQ doorbell recovery user entry */
+	__aligned_u64 sq_db_rec_addr;
+
+	/* address of RQ doorbell recovery user entry */
+	__aligned_u64 rq_db_rec_addr;
+
 };
 
 struct qedr_create_srq_ureq {
@@ -128,4 +145,12 @@ struct qedr_create_srq_uresp {
 	__u32 reserved1;
 };
 
+/* doorbell recovery entry allocated and populated by userspace doorbelling
+ * entities and mapped to kernel. Kernel uses this to register doorbell
+ * information with doorbell drop recovery mechanism.
+ */
+struct qedr_user_db_rec {
+	__aligned_u64 db_data; /* doorbell data */
+};
+
 #endif /* __QEDR_USER_H__ */