From de7b9a04b5bfd5cf40cc6c89dae3757f1823432a Mon Sep 17 00:00:00 2001
From: Chengchang Tang <tangchengchang@huawei.com>
Date: Tue, 26 Sep 2023 19:19:10 +0800
Subject: [PATCH 5/5] libhns: Fix missing reset notification.

driver inclusion
category: bugfix
bugzilla: https://gitee.com/src-openeuler/rdma-core/issues/I83L7U

----------------------------------------------------------

Currently, userspace driver get the reset notification by reading a
a shared variable which would be set to non-zero during reset. However,
if the user does not call driver's IO interface during reset, the reset
notification will be ignored. because this variable will be clear after
completes the reset.

This patch use a new reset flag to get whether the driver has been reset
at any time. A non-zero value will be assigned to this new reset
flag by default, which will permanently become 0 once a reset occurs.
During reset, the kernel space driver will assign 0 to this variable.
After reset, this variable will be remapped to a page of all zeros. The
userspace driver can judge whether the driver has been reset by whether
this variable is 0.

Fixes: 34f2ad8085c2 ("libhns: Add reset stop flow mechanism")
Signed-off-by: Chengchang Tang <tangchengchang@huawei.com>
---
 providers/hns/hns_roce_u.c       | 4 ++++
 providers/hns/hns_roce_u.h       | 2 ++
 providers/hns/hns_roce_u_hw_v2.c | 3 +++
 3 files changed, 9 insertions(+)

diff --git a/providers/hns/hns_roce_u.c b/providers/hns/hns_roce_u.c
index 87f9ed8..0660081 100644
--- a/providers/hns/hns_roce_u.c
+++ b/providers/hns/hns_roce_u.c
@@ -226,6 +226,7 @@ static int init_reset_context(struct hns_roce_context *ctx, int cmd_fd,
 			int page_size)
 {
 	uint64_t reset_mmap_key = resp->reset_mmap_key;
+	struct hns_roce_v2_reset_state *state;
 
 	/* The reset mmap key is 0, which means it is not supported. */
 	if (reset_mmap_key == 0)
@@ -236,6 +237,9 @@ static int init_reset_context(struct hns_roce_context *ctx, int cmd_fd,
 	if (ctx->reset_state == MAP_FAILED)
 		return -ENOMEM;
 
+	state = ctx->reset_state;
+	ctx->use_new_reset_flag = state->hw_ready;
+
 	return 0;
 }
 
diff --git a/providers/hns/hns_roce_u.h b/providers/hns/hns_roce_u.h
index b3f21ba..5501d8e 100644
--- a/providers/hns/hns_roce_u.h
+++ b/providers/hns/hns_roce_u.h
@@ -235,6 +235,7 @@ struct hns_roce_dca_ctx {
 
 struct hns_roce_v2_reset_state {
 	uint32_t is_reset;
+	uint32_t hw_ready;
 };
 
 struct hns_roce_cmd_flag {
@@ -278,6 +279,7 @@ struct hns_roce_context {
 
 	struct hns_roce_dca_ctx		dca_ctx;
 
+	bool use_new_reset_flag;
 	bool reseted;
 };
 
diff --git a/providers/hns/hns_roce_u_hw_v2.c b/providers/hns/hns_roce_u_hw_v2.c
index 29b6268..ac40d5d 100644
--- a/providers/hns/hns_roce_u_hw_v2.c
+++ b/providers/hns/hns_roce_u_hw_v2.c
@@ -1011,6 +1011,9 @@ static bool hns_roce_reseted(struct hns_roce_context *ctx)
 {
 	struct hns_roce_v2_reset_state *state = ctx->reset_state;
 
+	if (ctx->use_new_reset_flag)
+		return !state->hw_ready;
+
 	if (state && state->is_reset)
 		ctx->reseted = true;
 
-- 
2.25.1

