be2iscsi: Couple MCC tag and WRB alloc and free

WARN_ON(atomic_read(&mccq->used) >= mccq->len) seen when FW gets into
UE.

MCCQ overflow is happening because driver discards any new request and
frees up the tag. The tag allocation controls the number of MCC WRB
posted.  It is being replenished but WRBs are not hence the WARN_ON.

Allocation and freeing of WRB and tags for MCC is now done in one place.
This helps to achieve proper accounting of WRB indices and MCC tags.

Signed-off-by: Jitendra Bhivare <jitendra.bhivare@broadcom.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 51 insertions, 83 deletions

diff --git a/drivers/scsi/be2iscsi/be_mgmt.c b/drivers/scsi/be2iscsi/be_mgmt.c
index ccac1d7c7adc..83926e221f1e 100644
--- a/drivers/scsi/be2iscsi/be_mgmt.c
+++ b/drivers/scsi/be2iscsi/be_mgmt.c
@@ -161,20 +161,17 @@ int be_cmd_modify_eq_delay(struct beiscsi_hba *phba,
 	struct be_ctrl_info *ctrl = &phba->ctrl;
 	struct be_mcc_wrb *wrb;
 	struct be_cmd_req_modify_eq_delay *req;
-	unsigned int tag = 0;
+	unsigned int tag;
 	int i;
 
 	mutex_lock(&ctrl->mbox_lock);
-	tag = alloc_mcc_tag(phba);
-	if (!tag) {
+	wrb = alloc_mcc_wrb(phba, &tag);
+	if (!wrb) {
 		mutex_unlock(&ctrl->mbox_lock);
-		return tag;
+		return 0;
 	}
 
-	wrb = wrb_from_mccq(phba);
 	req = embedded_payload(wrb);
-
-	wrb->tag0 |= tag;
 	be_wrb_hdr_prepare(wrb, sizeof(*req), true, 0);
 	be_cmd_hdr_prepare(&req->hdr, CMD_SUBSYSTEM_COMMON,
 		OPCODE_COMMON_MODIFY_EQ_DELAY, sizeof(*req));
@@ -209,22 +206,20 @@ unsigned int mgmt_reopen_session(struct beiscsi_hba *phba,
 	struct be_ctrl_info *ctrl = &phba->ctrl;
 	struct be_mcc_wrb *wrb;
 	struct be_cmd_reopen_session_req *req;
-	unsigned int tag = 0;
+	unsigned int tag;
 
 	beiscsi_log(phba, KERN_INFO,
 		    BEISCSI_LOG_CONFIG | BEISCSI_LOG_MBOX,
 		    "BG_%d : In bescsi_get_boot_target\n");
 
 	mutex_lock(&ctrl->mbox_lock);
-	tag = alloc_mcc_tag(phba);
-	if (!tag) {
+	wrb = alloc_mcc_wrb(phba, &tag);
+	if (!wrb) {
 		mutex_unlock(&ctrl->mbox_lock);
-		return tag;
+		return 0;
 	}
 
-	wrb = wrb_from_mccq(phba);
 	req = embedded_payload(wrb);
-	wrb->tag0 |= tag;
 	be_wrb_hdr_prepare(wrb, sizeof(*req), true, 0);
 	be_cmd_hdr_prepare(&req->hdr, CMD_SUBSYSTEM_ISCSI_INI,
 			   OPCODE_ISCSI_INI_DRIVER_REOPEN_ALL_SESSIONS,
@@ -244,22 +239,20 @@ unsigned int mgmt_get_boot_target(struct beiscsi_hba *phba)
 	struct be_ctrl_info *ctrl = &phba->ctrl;
 	struct be_mcc_wrb *wrb;
 	struct be_cmd_get_boot_target_req *req;
-	unsigned int tag = 0;
+	unsigned int tag;
 
 	beiscsi_log(phba, KERN_INFO,
 		    BEISCSI_LOG_CONFIG | BEISCSI_LOG_MBOX,
 		    "BG_%d : In bescsi_get_boot_target\n");
 
 	mutex_lock(&ctrl->mbox_lock);
-	tag = alloc_mcc_tag(phba);
-	if (!tag) {
+	wrb = alloc_mcc_wrb(phba, &tag);
+	if (!wrb) {
 		mutex_unlock(&ctrl->mbox_lock);
-		return tag;
+		return 0;
 	}
 
-	wrb = wrb_from_mccq(phba);
 	req = embedded_payload(wrb);
-	wrb->tag0 |= tag;
 	be_wrb_hdr_prepare(wrb, sizeof(*req), true, 0);
 	be_cmd_hdr_prepare(&req->hdr, CMD_SUBSYSTEM_ISCSI_INI,
 			   OPCODE_ISCSI_INI_BOOT_GET_BOOT_TARGET,
@@ -276,7 +269,7 @@ unsigned int mgmt_get_session_info(struct beiscsi_hba *phba,
 {
 	struct be_ctrl_info *ctrl = &phba->ctrl;
 	struct be_mcc_wrb *wrb;
-	unsigned int tag = 0;
+	unsigned int tag;
 	struct  be_cmd_get_session_req *req;
 	struct be_cmd_get_session_resp *resp;
 	struct be_sge *sge;
@@ -286,21 +279,16 @@ unsigned int mgmt_get_session_info(struct beiscsi_hba *phba,
 		    "BG_%d : In beiscsi_get_session_info\n");
 
 	mutex_lock(&ctrl->mbox_lock);
-	tag = alloc_mcc_tag(phba);
-	if (!tag) {
+	wrb = alloc_mcc_wrb(phba, &tag);
+	if (!wrb) {
 		mutex_unlock(&ctrl->mbox_lock);
-		return tag;
+		return 0;
 	}
 
 	nonemb_cmd->size = sizeof(*resp);
 	req = nonemb_cmd->va;
 	memset(req, 0, sizeof(*req));
-	wrb = wrb_from_mccq(phba);
 	sge = nonembedded_sgl(wrb);
-	wrb->tag0 |= tag;
-
-
-	wrb->tag0 |= tag;
 	be_wrb_hdr_prepare(wrb, sizeof(*req), false, 1);
 	be_cmd_hdr_prepare(&req->hdr, CMD_SUBSYSTEM_ISCSI_INI,
 			   OPCODE_ISCSI_INI_SESSION_GET_A_SESSION,
@@ -624,20 +612,18 @@ unsigned int mgmt_vendor_specific_fw_cmd(struct be_ctrl_info *ctrl,
 		return -ENOSYS;
 	}
 
-	tag = alloc_mcc_tag(phba);
-	if (!tag) {
+	wrb = alloc_mcc_wrb(phba, &tag);
+	if (!wrb) {
 		mutex_unlock(&ctrl->mbox_lock);
-		return tag;
+		return 0;
 	}
 
-	wrb = wrb_from_mccq(phba);
 	mcc_sge = nonembedded_sgl(wrb);
 	be_wrb_hdr_prepare(wrb, nonemb_cmd->size, false,
 			   job->request_payload.sg_cnt);
 	mcc_sge->pa_hi = cpu_to_le32(upper_32_bits(nonemb_cmd->dma));
 	mcc_sge->pa_lo = cpu_to_le32(nonemb_cmd->dma & 0xFFFFFFFF);
 	mcc_sge->len = cpu_to_le32(nonemb_cmd->size);
-	wrb->tag0 |= tag;
 
 	be_mcc_notify(phba, tag);
 
@@ -657,22 +643,22 @@ unsigned int mgmt_vendor_specific_fw_cmd(struct be_ctrl_info *ctrl,
 int mgmt_epfw_cleanup(struct beiscsi_hba *phba, unsigned short ulp_num)
 {
 	struct be_ctrl_info *ctrl = &phba->ctrl;
-	struct be_mcc_wrb *wrb = wrb_from_mccq(phba);
-	struct iscsi_cleanup_req *req = embedded_payload(wrb);
+	struct be_mcc_wrb *wrb;
+	struct iscsi_cleanup_req *req;
 	unsigned int tag;
 	int status;
 
 	mutex_lock(&ctrl->mbox_lock);
-	tag = alloc_mcc_tag(phba);
-	if (!tag) {
+	wrb = alloc_mcc_wrb(phba, &tag);
+	if (!wrb) {
 		mutex_unlock(&ctrl->mbox_lock);
 		return -EBUSY;
 	}
 
+	req = embedded_payload(wrb);
 	be_wrb_hdr_prepare(wrb, sizeof(*req), true, 0);
 	be_cmd_hdr_prepare(&req->hdr, CMD_SUBSYSTEM_ISCSI,
 			   OPCODE_COMMON_ISCSI_CLEANUP, sizeof(*req));
-	wrb->tag0 |= tag;
 
 	req->chute = (1 << ulp_num);
 	req->hdr_ring_id = cpu_to_le16(HWI_GET_DEF_HDRQ_ID(phba, ulp_num));
@@ -697,20 +683,18 @@ unsigned int  mgmt_invalidate_icds(struct beiscsi_hba *phba,
 	struct be_mcc_wrb *wrb;
 	struct be_sge *sge;
 	struct invalidate_commands_params_in *req;
-	unsigned int i, tag = 0;
+	unsigned int i, tag;
 
 	mutex_lock(&ctrl->mbox_lock);
-	tag = alloc_mcc_tag(phba);
-	if (!tag) {
+	wrb = alloc_mcc_wrb(phba, &tag);
+	if (!wrb) {
 		mutex_unlock(&ctrl->mbox_lock);
-		return tag;
+		return 0;
 	}
 
 	req = nonemb_cmd->va;
 	memset(req, 0, sizeof(*req));
-	wrb = wrb_from_mccq(phba);
 	sge = nonembedded_sgl(wrb);
-	wrb->tag0 |= tag;
 
 	be_wrb_hdr_prepare(wrb, sizeof(*req), false, 1);
 	be_cmd_hdr_prepare(&req->hdr, CMD_SUBSYSTEM_ISCSI,
@@ -745,15 +729,13 @@ unsigned int mgmt_invalidate_connection(struct beiscsi_hba *phba,
 	unsigned int tag = 0;
 
 	mutex_lock(&ctrl->mbox_lock);
-	tag = alloc_mcc_tag(phba);
-	if (!tag) {
+	wrb = alloc_mcc_wrb(phba, &tag);
+	if (!wrb) {
 		mutex_unlock(&ctrl->mbox_lock);
-		return tag;
+		return 0;
 	}
-	wrb = wrb_from_mccq(phba);
-	wrb->tag0 |= tag;
-	req = embedded_payload(wrb);
 
+	req = embedded_payload(wrb);
 	be_wrb_hdr_prepare(wrb, sizeof(*req), true, 0);
 	be_cmd_hdr_prepare(&req->hdr, CMD_SUBSYSTEM_ISCSI_INI,
 			   OPCODE_ISCSI_INI_DRIVER_INVALIDATE_CONNECTION,
@@ -776,18 +758,16 @@ unsigned int mgmt_upload_connection(struct beiscsi_hba *phba,
 	struct be_ctrl_info *ctrl = &phba->ctrl;
 	struct be_mcc_wrb *wrb;
 	struct tcp_upload_params_in *req;
-	unsigned int tag = 0;
+	unsigned int tag;
 
 	mutex_lock(&ctrl->mbox_lock);
-	tag = alloc_mcc_tag(phba);
-	if (!tag) {
+	wrb = alloc_mcc_wrb(phba, &tag);
+	if (!wrb) {
 		mutex_unlock(&ctrl->mbox_lock);
-		return tag;
+		return 0;
 	}
-	wrb = wrb_from_mccq(phba);
-	req = embedded_payload(wrb);
-	wrb->tag0 |= tag;
 
+	req = embedded_payload(wrb);
 	be_wrb_hdr_prepare(wrb, sizeof(*req), true, 0);
 	be_cmd_hdr_prepare(&req->hdr, CMD_COMMON_TCP_UPLOAD,
 			   OPCODE_COMMON_TCP_UPLOAD, sizeof(*req));
@@ -848,17 +828,15 @@ int mgmt_open_connection(struct beiscsi_hba *phba,
 	ISCSI_GET_PDU_TEMPLATE_ADDRESS(phba, ptemplate_address);
 	if (mutex_lock_interruptible(&ctrl->mbox_lock))
 		return 0;
-	tag = alloc_mcc_tag(phba);
-	if (!tag) {
+	wrb = alloc_mcc_wrb(phba, &tag);
+	if (!wrb) {
 		mutex_unlock(&ctrl->mbox_lock);
-		return tag;
+		return 0;
 	}
-	wrb = wrb_from_mccq(phba);
-	sge = nonembedded_sgl(wrb);
 
+	sge = nonembedded_sgl(wrb);
 	req = nonemb_cmd->va;
 	memset(req, 0, sizeof(*req));
-	wrb->tag0 |= tag;
 
 	be_wrb_hdr_prepare(wrb, nonemb_cmd->size, false, 1);
 	be_cmd_hdr_prepare(&req->hdr, CMD_SUBSYSTEM_ISCSI,
@@ -925,16 +903,13 @@ unsigned int mgmt_get_all_if_id(struct beiscsi_hba *phba)
 
 	if (mutex_lock_interruptible(&ctrl->mbox_lock))
 		return -EINTR;
-	tag = alloc_mcc_tag(phba);
-	if (!tag) {
+	wrb = alloc_mcc_wrb(phba, &tag);
+	if (!wrb) {
 		mutex_unlock(&ctrl->mbox_lock);
 		return -ENOMEM;
 	}
 
-	wrb = wrb_from_mccq(phba);
 	req = embedded_payload(wrb);
-	wrb->tag0 |= tag;
-
 	be_wrb_hdr_prepare(wrb, sizeof(*req), true, 0);
 	be_cmd_hdr_prepare(&req->hdr, CMD_SUBSYSTEM_ISCSI,
 			   OPCODE_COMMON_ISCSI_NTWK_GET_ALL_IF_ID,
@@ -974,17 +949,14 @@ static int mgmt_exec_nonemb_cmd(struct beiscsi_hba *phba,
 	int rc = 0;
 
 	mutex_lock(&ctrl->mbox_lock);
-	tag = alloc_mcc_tag(phba);
-	if (!tag) {
+	wrb = alloc_mcc_wrb(phba, &tag);
+	if (!wrb) {
 		mutex_unlock(&ctrl->mbox_lock);
 		rc = -ENOMEM;
 		goto free_cmd;
 	}
 
-	wrb = wrb_from_mccq(phba);
-	wrb->tag0 |= tag;
 	sge = nonembedded_sgl(wrb);
-
 	be_wrb_hdr_prepare(wrb, nonemb_cmd->size, false, 1);
 	sge->pa_hi = cpu_to_le32(upper_32_bits(nonemb_cmd->dma));
 	sge->pa_lo = cpu_to_le32(lower_32_bits(nonemb_cmd->dma));
@@ -1368,22 +1340,20 @@ int mgmt_get_nic_conf(struct beiscsi_hba *phba,
 
 unsigned int be_cmd_get_initname(struct beiscsi_hba *phba)
 {
-	unsigned int tag = 0;
+	unsigned int tag;
 	struct be_mcc_wrb *wrb;
 	struct be_cmd_hba_name *req;
 	struct be_ctrl_info *ctrl = &phba->ctrl;
 
 	if (mutex_lock_interruptible(&ctrl->mbox_lock))
 		return 0;
-	tag = alloc_mcc_tag(phba);
-	if (!tag) {
+	wrb = alloc_mcc_wrb(phba, &tag);
+	if (!wrb) {
 		mutex_unlock(&ctrl->mbox_lock);
-		return tag;
+		return 0;
 	}
 
-	wrb = wrb_from_mccq(phba);
 	req = embedded_payload(wrb);
-	wrb->tag0 |= tag;
 	be_wrb_hdr_prepare(wrb, sizeof(*req), true, 0);
 	be_cmd_hdr_prepare(&req->hdr, CMD_SUBSYSTEM_ISCSI_INI,
 			OPCODE_ISCSI_INI_CFG_GET_HBA_NAME,
@@ -1847,8 +1817,8 @@ int beiscsi_logout_fw_sess(struct beiscsi_hba *phba,
 		    "BG_%d : In bescsi_logout_fwboot_sess\n");
 
 	mutex_lock(&ctrl->mbox_lock);
-	tag = alloc_mcc_tag(phba);
-	if (!tag) {
+	wrb = alloc_mcc_wrb(phba, &tag);
+	if (!wrb) {
 		mutex_unlock(&ctrl->mbox_lock);
 		beiscsi_log(phba, KERN_INFO,
 			    BEISCSI_LOG_CONFIG | BEISCSI_LOG_MBOX,
@@ -1856,9 +1826,7 @@ int beiscsi_logout_fw_sess(struct beiscsi_hba *phba,
 		return -EINVAL;
 	}
 
-	wrb = wrb_from_mccq(phba);
 	req = embedded_payload(wrb);
-	wrb->tag0 |= tag;
 	be_wrb_hdr_prepare(wrb, sizeof(*req), true, 0);
 	be_cmd_hdr_prepare(&req->hdr, CMD_SUBSYSTEM_ISCSI_INI,
 			   OPCODE_ISCSI_INI_SESSION_LOGOUT_TARGET,