scsi: bnx2fc: Process the RQE with CQE in interrupt context

Filesystem goes to read-only after continuous error injection because RQE
was handled in deferred context, leading to mismatch between CQE and RQE.

Specifically, this patch makes the following changes:

 - Process the RQE with CQE in interrupt context, before putting it into
   the work queue.

 - Producer and consumer indices are also updated in the interrupt context
   to guarantee the the order of processing.

[mkp: fixed bad indentation]

Link: https://lore.kernel.org/r/20200327054849.15947-2-skashyap@marvell.com
Signed-off-by: Javed Hasan <jhasan@marvell.com>
Signed-off-by: Saurav Kashyap <skashyap@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 7 insertions, 21 deletions

diff --git a/drivers/scsi/bnx2fc/bnx2fc_io.c b/drivers/scsi/bnx2fc/bnx2fc_io.c
index 4c8122a82322..9ab915240a2a 100644
--- a/drivers/scsi/bnx2fc/bnx2fc_io.c
+++ b/drivers/scsi/bnx2fc/bnx2fc_io.c
@@ -24,7 +24,7 @@ static void bnx2fc_unmap_sg_list(struct bnx2fc_cmd *io_req);
 static void bnx2fc_free_mp_resc(struct bnx2fc_cmd *io_req);
 static void bnx2fc_parse_fcp_rsp(struct bnx2fc_cmd *io_req,
 				 struct fcoe_fcp_rsp_payload *fcp_rsp,
-				 u8 num_rq);
+				 u8 num_rq, unsigned char *rq_data);
 
 void bnx2fc_cmd_timer_set(struct bnx2fc_cmd *io_req,
 			  unsigned int timer_msec)
@@ -1518,7 +1518,8 @@ static void bnx2fc_tgt_reset_cmpl(struct bnx2fc_cmd *io_req)
 }
 
 void bnx2fc_process_tm_compl(struct bnx2fc_cmd *io_req,
-			     struct fcoe_task_ctx_entry *task, u8 num_rq)
+			     struct fcoe_task_ctx_entry *task, u8 num_rq,
+				  unsigned char *rq_data)
 {
 	struct bnx2fc_mp_req *tm_req;
 	struct fc_frame_header *fc_hdr;
@@ -1557,7 +1558,7 @@ void bnx2fc_process_tm_compl(struct bnx2fc_cmd *io_req,
 	if (fc_hdr->fh_r_ctl == FC_RCTL_DD_CMD_STATUS) {
 		bnx2fc_parse_fcp_rsp(io_req,
 				     (struct fcoe_fcp_rsp_payload *)
-				     rsp_buf, num_rq);
+				     rsp_buf, num_rq, rq_data);
 		if (io_req->fcp_rsp_code == 0) {
 			/* TM successful */
 			if (tm_req->tm_flags & FCP_TMF_LUN_RESET)
@@ -1755,15 +1756,11 @@ void bnx2fc_build_fcp_cmnd(struct bnx2fc_cmd *io_req,
 
 static void bnx2fc_parse_fcp_rsp(struct bnx2fc_cmd *io_req,
 				 struct fcoe_fcp_rsp_payload *fcp_rsp,
-				 u8 num_rq)
+				 u8 num_rq, unsigned char *rq_data)
 {
 	struct scsi_cmnd *sc_cmd = io_req->sc_cmd;
-	struct bnx2fc_rport *tgt = io_req->tgt;
 	u8 rsp_flags = fcp_rsp->fcp_flags.flags;
 	u32 rq_buff_len = 0;
-	int i;
-	unsigned char *rq_data;
-	unsigned char *dummy;
 	int fcp_sns_len = 0;
 	int fcp_rsp_len = 0;
 
@@ -1809,14 +1806,6 @@ static void bnx2fc_parse_fcp_rsp(struct bnx2fc_cmd *io_req,
 			rq_buff_len =  num_rq * BNX2FC_RQ_BUF_SZ;
 		}
 
-		rq_data = bnx2fc_get_next_rqe(tgt, 1);
-
-		if (num_rq > 1) {
-			/* We do not need extra sense data */
-			for (i = 1; i < num_rq; i++)
-				dummy = bnx2fc_get_next_rqe(tgt, 1);
-		}
-
 		/* fetch fcp_rsp_code */
 		if ((fcp_rsp_len == 4) || (fcp_rsp_len == 8)) {
 			/* Only for task management function */
@@ -1837,9 +1826,6 @@ static void bnx2fc_parse_fcp_rsp(struct bnx2fc_cmd *io_req,
 		if (fcp_sns_len)
 			memcpy(sc_cmd->sense_buffer, rq_data, fcp_sns_len);
 
-		/* return RQ entries */
-		for (i = 0; i < num_rq; i++)
-			bnx2fc_return_rqe(tgt, 1);
 	}
 }
 
@@ -1918,7 +1904,7 @@ exit_qcmd:
 
 void bnx2fc_process_scsi_cmd_compl(struct bnx2fc_cmd *io_req,
 				   struct fcoe_task_ctx_entry *task,
-				   u8 num_rq)
+				   u8 num_rq, unsigned char *rq_data)
 {
 	struct fcoe_fcp_rsp_payload *fcp_rsp;
 	struct bnx2fc_rport *tgt = io_req->tgt;
@@ -1950,7 +1936,7 @@ void bnx2fc_process_scsi_cmd_compl(struct bnx2fc_cmd *io_req,
 		   &(task->rxwr_only.union_ctx.comp_info.fcp_rsp.payload);
 
 	/* parse fcp_rsp and obtain sense data from RQ if available */
-	bnx2fc_parse_fcp_rsp(io_req, fcp_rsp, num_rq);
+	bnx2fc_parse_fcp_rsp(io_req, fcp_rsp, num_rq, rq_data);
 
 	if (!sc_cmd->SCp.ptr) {
 		printk(KERN_ERR PFX "SCp.ptr is NULL\n");