From e4a976254ec5ebdcdb3e1e1b40e795b3db6b6dab Mon Sep 17 00:00:00 2001
From: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Date: Wed, 12 Dec 2018 15:11:39 -0800
Patch-mainline: v5.0-rc1
Git-commit: e4a976254ec5ebdcdb3e1e1b40e795b3db6b6dab
Subject: [PATCH] nvmet: add error-log definitions
References: bsc#1181161

This patch adds necessary fields in the target data structures to
support error log page. For a target controller, we add a new error log
field to maintain the error log, at any given point we maintain error
entries equal to NVMET_ERROR_LOG_SLOTS for each controller. In the
following patch, we also update the error log page entry in the I/O
completion path so we introduce a spinlock for synchronization of the
log.

For nvmet_req, we add a new field error_loc to hold the location of
the error in the command when the actual error occurs for each request
and a starting LBA if applicable.

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Enzo Matsumiya <ematsumiya@suse.de>
---
 drivers/nvme/target/core.c  | 5 +++++
 drivers/nvme/target/nvmet.h | 6 ++++++
 2 files changed, 11 insertions(+)

--- a/drivers/nvme/target/core.c
+++ b/drivers/nvme/target/core.c
@@ -668,6 +668,8 @@ bool nvmet_req_init(struct nvmet_req *re
 	req->rsp->status = 0;
 	req->rsp->sq_head = 0;
 	req->ns = NULL;
+	req->error_loc = -1;
+	req->error_slba = 0;
 
 	/* no support for fused commands yet */
 	if (unlikely(flags & (NVME_CMD_FUSE_FIRST | NVME_CMD_FUSE_SECOND))) {
@@ -996,6 +998,9 @@ u16 nvmet_alloc_ctrl(const char *subsysn
 	/* keep-alive timeout in seconds */
 	ctrl->kato = DIV_ROUND_UP(kato, 1000);
 
+	ctrl->err_counter = 0;
+	spin_lock_init(&ctrl->error_lock);
+
 	nvmet_start_keep_alive_timer(ctrl);
 
 	mutex_lock(&subsys->lock);
--- a/drivers/nvme/target/nvmet.h
+++ b/drivers/nvme/target/nvmet.h
@@ -190,6 +190,10 @@ struct nvmet_ctrl {
 
 	char			subsysnqn[NVMF_NQN_FIELD_LEN];
 	char			hostnqn[NVMF_NQN_FIELD_LEN];
+
+	spinlock_t		error_lock;
+	u64			err_counter;
+	struct nvme_error_slot	slots[NVMET_ERROR_LOG_SLOTS];
 };
 
 struct nvmet_subsys {
@@ -302,6 +306,9 @@ struct nvmet_req {
 
 	void (*execute)(struct nvmet_req *req);
 	const struct nvmet_fabrics_ops *ops;
+
+	u16			error_loc;
+	u64			error_slba;
 };
 
 extern struct workqueue_struct *buffered_io_wq;