[PATCH net-next 0/9] Add support of VF Reset to HNS3 VF driver

[PATCH net-next 0/9] Add support of VF Reset to HNS3 VF driver

[Salil Mehta]

This patch-set adds the support of VF reset to the existing VF driver.
VF Reset can be triggered due to TX watchdog firing  as a result of TX
data-path not working. VF reset could also be a result of some internal
configuration changes if that requires reset, or as a result of the
PF/Core/Global/IMP(Integrated Management Processor) reset happened in
the PF. 

Summary of Patches:
* Watchdog timer trigger chnages are present in Patch 1.
* Reset Service Task and related Event handling is present in Patches {2,3}
* Changes to send reset request to PF, reset stack and re-initialization
  of the hclge device is present in Patches {4,5,6}
* Changes related to ARQ (Asynchronous Receive Queue) and its event handling
  are present in Patches {7,8}
* Changes required in PF to handle the VF Reset request and actually perform
  hardware VF reset is there in Patch 9.


NOTE: This patch depends upon "[PATCH net-next 00/11] fix some bugs for HNS3 driver"
	Link: https://lkml.org/lkml/2018/3/21/72

Salil Mehta (9):
  net: hns3: Changes to make enet watchdog timeout func common for PF/VF
  net: hns3: Add VF Reset Service Task to support event handling
  net: hns3: Add VF Reset device state and its handling
  net: hns3: Add support to request VF Reset to PF
  net: hns3: Add support to reset the enet/ring mgmt layer
  net: hns3: Add support to re-initialize the hclge device
  net: hns3: Changes to support ARQ(Asynchronous Receive Queue)
  net: hns3: Add *Asserting Reset* mailbox message & handling in VF
  net: hns3: Changes required in PF mailbox to support VF reset

 drivers/net/ethernet/hisilicon/hns3/hclge_mbx.h    |  16 +
 drivers/net/ethernet/hisilicon/hns3/hnae3.h        |   8 +-
 drivers/net/ethernet/hisilicon/hns3/hns3_enet.c    |  30 +-
 drivers/net/ethernet/hisilicon/hns3/hns3_enet.h    |   2 -
 .../ethernet/hisilicon/hns3/hns3pf/hclge_main.c    |  38 +--
 .../ethernet/hisilicon/hns3/hns3pf/hclge_main.h    |   1 +
 .../net/ethernet/hisilicon/hns3/hns3pf/hclge_mbx.c |  42 +++
 .../ethernet/hisilicon/hns3/hns3vf/hclgevf_cmd.c   |   6 +
 .../ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c  | 336 +++++++++++++++++++--
 .../ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h  |  31 ++
 .../ethernet/hisilicon/hns3/hns3vf/hclgevf_mbx.c   |  95 +++++-
 11 files changed, 534 insertions(+), 71 deletions(-)

-- 
2.7.4

[PATCH net-next 1/9] net: hns3: Changes to make enet watchdog timeout func common for PF/VF

[Salil Mehta]

HNS3 drivers enet layer, used for the ring management and stack
interaction, is common to both VF and PF. PF already supports reset
functionality to handle the network stack watchdog timeout trigger
but the existing code is not generic enough to be used to support VF
reset as well.
This patch does following:
1. Makes the existing watchdog timeout handler in enet layer generic
   i.e. suitable for both VF and PF and
2. Introduces the new reset event handler for the VF code.
3. Changes existing reset event handler of PF code to initialize the
   reset level

Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
---
 drivers/net/ethernet/hisilicon/hns3/hnae3.h        |  7 +++--
 drivers/net/ethernet/hisilicon/hns3/hns3_enet.c    | 30 +++++-------------
 drivers/net/ethernet/hisilicon/hns3/hns3_enet.h    |  2 --
 .../ethernet/hisilicon/hns3/hns3pf/hclge_main.c    | 36 ++++++++++++----------
 .../ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c  | 14 +++++++++
 5 files changed, 46 insertions(+), 43 deletions(-)

diff --git a/drivers/net/ethernet/hisilicon/hns3/hnae3.h b/drivers/net/ethernet/hisilicon/hns3/hnae3.h
index 9daa88d..56f9e650 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hnae3.h
+++ b/drivers/net/ethernet/hisilicon/hns3/hnae3.h
@@ -118,6 +118,7 @@ enum hnae3_reset_notify_type {
 };
 
 enum hnae3_reset_type {
+	HNAE3_VF_RESET,
 	HNAE3_FUNC_RESET,
 	HNAE3_CORE_RESET,
 	HNAE3_GLOBAL_RESET,
@@ -400,8 +401,7 @@ struct hnae3_ae_ops {
 	int (*set_vf_vlan_filter)(struct hnae3_handle *handle, int vfid,
 				  u16 vlan, u8 qos, __be16 proto);
 	int (*enable_hw_strip_rxvtag)(struct hnae3_handle *handle, bool enable);
-	void (*reset_event)(struct hnae3_handle *handle,
-			    enum hnae3_reset_type reset);
+	void (*reset_event)(struct hnae3_handle *handle);
 	void (*get_channels)(struct hnae3_handle *handle,
 			     struct ethtool_channels *ch);
 	void (*get_tqps_and_rss_info)(struct hnae3_handle *h,
@@ -495,6 +495,9 @@ struct hnae3_handle {
 	struct hnae3_ae_algo *ae_algo;  /* the class who provides this handle */
 	u64 flags; /* Indicate the capabilities for this handle*/
 
+	unsigned long last_reset_time;
+	enum hnae3_reset_type reset_level;
+
 	union {
 		struct net_device *netdev; /* first member */
 		struct hnae3_knic_private_info kinfo;
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
index 0b4a676..40a3eb7 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
@@ -320,7 +320,7 @@ static int hns3_nic_net_open(struct net_device *netdev)
 		return ret;
 	}
 
-	priv->last_reset_time = jiffies;
+	priv->ae_handle->last_reset_time = jiffies;
 	return 0;
 }
 
@@ -1543,7 +1543,6 @@ static bool hns3_get_tx_timeo_queue_info(struct net_device *ndev)
 static void hns3_nic_net_timeout(struct net_device *ndev)
 {
 	struct hns3_nic_priv *priv = netdev_priv(ndev);
-	unsigned long last_reset_time = priv->last_reset_time;
 	struct hnae3_handle *h = priv->ae_handle;
 
 	if (!hns3_get_tx_timeo_queue_info(ndev))
@@ -1551,24 +1550,12 @@ static void hns3_nic_net_timeout(struct net_device *ndev)
 
 	priv->tx_timeout_count++;
 
-	/* This timeout is far away enough from last timeout,
-	 * if timeout again,set the reset type to PF reset
-	 */
-	if (time_after(jiffies, (last_reset_time + 20 * HZ)))
-		priv->reset_level = HNAE3_FUNC_RESET;
-
-	/* Don't do any new action before the next timeout */
-	else if (time_before(jiffies, (last_reset_time + ndev->watchdog_timeo)))
+	if (time_before(jiffies, (h->last_reset_time + ndev->watchdog_timeo)))
 		return;
 
-	priv->last_reset_time = jiffies;
-
+	/* request the reset */
 	if (h->ae_algo->ops->reset_event)
-		h->ae_algo->ops->reset_event(h, priv->reset_level);
-
-	priv->reset_level++;
-	if (priv->reset_level > HNAE3_GLOBAL_RESET)
-		priv->reset_level = HNAE3_GLOBAL_RESET;
+		h->ae_algo->ops->reset_event(h);
 }
 
 static const struct net_device_ops hns3_nic_netdev_ops = {
@@ -3122,8 +3109,8 @@ static int hns3_client_init(struct hnae3_handle *handle)
 	priv->dev = &pdev->dev;
 	priv->netdev = netdev;
 	priv->ae_handle = handle;
-	priv->last_reset_time = jiffies;
-	priv->reset_level = HNAE3_FUNC_RESET;
+	priv->ae_handle->reset_level = HNAE3_NONE_RESET;
+	priv->ae_handle->last_reset_time = jiffies;
 	priv->tx_timeout_count = 0;
 
 	handle->kinfo.netdev = netdev;
@@ -3355,7 +3342,6 @@ static int hns3_reset_notify_down_enet(struct hnae3_handle *handle)
 static int hns3_reset_notify_up_enet(struct hnae3_handle *handle)
 {
 	struct hnae3_knic_private_info *kinfo = &handle->kinfo;
-	struct hns3_nic_priv *priv = netdev_priv(kinfo->netdev);
 	int ret = 0;
 
 	if (netif_running(kinfo->netdev)) {
@@ -3365,8 +3351,7 @@ static int hns3_reset_notify_up_enet(struct hnae3_handle *handle)
 				   "hns net up fail, ret=%d!\n", ret);
 			return ret;
 		}
-
-		priv->last_reset_time = jiffies;
+		handle->last_reset_time = jiffies;
 	}
 
 	return ret;
@@ -3378,7 +3363,6 @@ static int hns3_reset_notify_init_enet(struct hnae3_handle *handle)
 	struct hns3_nic_priv *priv = netdev_priv(netdev);
 	int ret;
 
-	priv->reset_level = 1;
 	hns3_init_mac_addr(netdev);
 	hns3_nic_set_rx_mode(netdev);
 	hns3_recover_hw_addr(netdev);
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h
index 39daa01..9e4cfbb 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h
@@ -532,8 +532,6 @@ struct hns3_nic_priv {
 	/* The most recently read link state */
 	int link;
 	u64 tx_timeout_count;
-	enum hnae3_reset_type reset_level;
-	unsigned long last_reset_time;
 
 	unsigned long state;
 
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
index 31e90b5..a3e00da 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
@@ -2845,27 +2845,31 @@ static void hclge_reset(struct hclge_dev *hdev)
 	hclge_notify_client(hdev, HNAE3_UP_CLIENT);
 }
 
-static void hclge_reset_event(struct hnae3_handle *handle,
-			      enum hnae3_reset_type reset)
+static void hclge_reset_event(struct hnae3_handle *handle)
 {
 	struct hclge_vport *vport = hclge_get_vport(handle);
 	struct hclge_dev *hdev = vport->back;
 
-	dev_info(&hdev->pdev->dev,
-		 "Receive reset event , reset_type is %d", reset);
+	/* check if this is a new reset request and we are not here just because
+	 * last reset attempt did not succeed and watchdog hit us again. We will
+	 * know this if last reset request did not occur very recently (watchdog
+	 * timer = 5*HZ, let us check after sufficiently large time, say 4*5*Hz)
+	 * In case of new request we reset the "reset level" to PF reset.
+	 */
+	if (time_after(jiffies, (handle->last_reset_time + 4 * 5 * HZ)))
+		handle->reset_level = HNAE3_FUNC_RESET;
 
-	switch (reset) {
-	case HNAE3_FUNC_RESET:
-	case HNAE3_CORE_RESET:
-	case HNAE3_GLOBAL_RESET:
-		/* request reset & schedule reset task */
-		set_bit(reset, &hdev->reset_request);
-		hclge_reset_task_schedule(hdev);
-		break;
-	default:
-		dev_warn(&hdev->pdev->dev, "Unsupported reset event:%d", reset);
-		break;
-	}
+	dev_info(&hdev->pdev->dev, "received reset event , reset type is %d",
+		 handle->reset_level);
+
+	/* request reset & schedule reset task */
+	set_bit(handle->reset_level, &hdev->reset_request);
+	hclge_reset_task_schedule(hdev);
+
+	if (handle->reset_level < HNAE3_GLOBAL_RESET)
+		handle->reset_level++;
+
+	handle->last_reset_time = jiffies;
 }
 
 static void hclge_reset_subtask(struct hclge_dev *hdev)
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
index 906dfa3..6c3881d 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
@@ -832,6 +832,19 @@ static void hclgevf_reset_tqp(struct hnae3_handle *handle, u16 queue_id)
 			     2, true, NULL, 0);
 }
 
+static void hclgevf_reset_event(struct hnae3_handle *handle)
+{
+	struct hclgevf_dev *hdev = hclgevf_ae_get_hdev(handle);
+
+	dev_info(&hdev->pdev->dev, "received reset request from VF enet\n");
+
+	handle->reset_level = HNAE3_VF_RESET;
+
+	/* request VF reset here. Code added later */
+
+	handle->last_reset_time = jiffies;
+}
+
 static u32 hclgevf_get_fw_version(struct hnae3_handle *handle)
 {
 	struct hclgevf_dev *hdev = hclgevf_ae_get_hdev(handle);
@@ -1526,6 +1539,7 @@ static const struct hnae3_ae_ops hclgevf_ops = {
 	.get_tc_size = hclgevf_get_tc_size,
 	.get_fw_version = hclgevf_get_fw_version,
 	.set_vlan_filter = hclgevf_set_vlan_filter,
+	.reset_event = hclgevf_reset_event,
 	.get_channels = hclgevf_get_channels,
 	.get_tqps_and_rss_info = hclgevf_get_tqps_and_rss_info,
 	.get_status = hclgevf_get_status,
-- 
2.7.4

[PATCH net-next 2/9] net: hns3: Add VF Reset Service Task to support event handling

[Salil Mehta]

VF reset would involve handling of different reset related events
from the stack, physical function, mailbox etc. Reset service task
would be used in servicing such reset event requests and later
handling the hardware completions waits and initiating the stack
resets.

Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
---
 .../ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c  | 31 ++++++++++++++++++++++
 .../ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h  |  4 +++
 2 files changed, 35 insertions(+)

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
index 6c3881d..cdb6e7a 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
@@ -867,6 +867,15 @@ static void hclgevf_get_misc_vector(struct hclgevf_dev *hdev)
 	hdev->num_msi_used += 1;
 }
 
+void hclgevf_reset_task_schedule(struct hclgevf_dev *hdev)
+{
+	if (!test_bit(HCLGEVF_STATE_RST_SERVICE_SCHED, &hdev->state) &&
+	    !test_bit(HCLGEVF_STATE_RST_HANDLING, &hdev->state)) {
+		set_bit(HCLGEVF_STATE_RST_SERVICE_SCHED, &hdev->state);
+		schedule_work(&hdev->rst_service_task);
+	}
+}
+
 static void hclgevf_mbx_task_schedule(struct hclgevf_dev *hdev)
 {
 	if (!test_and_set_bit(HCLGEVF_STATE_MBX_SERVICE_SCHED, &hdev->state))
@@ -889,6 +898,24 @@ static void hclgevf_service_timer(struct timer_list *t)
 	hclgevf_task_schedule(hdev);
 }
 
+static void hclgevf_reset_service_task(struct work_struct *work)
+{
+	struct hclgevf_dev *hdev =
+		container_of(work, struct hclgevf_dev, rst_service_task);
+
+	if (test_and_set_bit(HCLGEVF_STATE_RST_HANDLING, &hdev->state))
+		return;
+
+	clear_bit(HCLGEVF_STATE_RST_SERVICE_SCHED, &hdev->state);
+
+	/* body of the reset service task will constitute of hclge device
+	 * reset state handling. This code shall be added subsequently in
+	 * next patches.
+	 */
+
+	clear_bit(HCLGEVF_STATE_RST_HANDLING, &hdev->state);
+}
+
 static void hclgevf_mailbox_service_task(struct work_struct *work)
 {
 	struct hclgevf_dev *hdev;
@@ -1097,6 +1124,8 @@ static void hclgevf_state_init(struct hclgevf_dev *hdev)
 	INIT_WORK(&hdev->service_task, hclgevf_service_task);
 	clear_bit(HCLGEVF_STATE_SERVICE_SCHED, &hdev->state);
 
+	INIT_WORK(&hdev->rst_service_task, hclgevf_reset_service_task);
+
 	mutex_init(&hdev->mbx_resp.mbx_mutex);
 
 	/* bring the device down */
@@ -1113,6 +1142,8 @@ static void hclgevf_state_uninit(struct hclgevf_dev *hdev)
 		cancel_work_sync(&hdev->service_task);
 	if (hdev->mbx_service_task.func)
 		cancel_work_sync(&hdev->mbx_service_task);
+	if (hdev->rst_service_task.func)
+		cancel_work_sync(&hdev->rst_service_task);
 
 	mutex_destroy(&hdev->mbx_resp.mbx_mutex);
 }
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h
index 0eaea06..8b5fa67 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h
@@ -52,6 +52,8 @@ enum hclgevf_states {
 	HCLGEVF_STATE_DISABLED,
 	/* task states */
 	HCLGEVF_STATE_SERVICE_SCHED,
+	HCLGEVF_STATE_RST_SERVICE_SCHED,
+	HCLGEVF_STATE_RST_HANDLING,
 	HCLGEVF_STATE_MBX_SERVICE_SCHED,
 	HCLGEVF_STATE_MBX_HANDLING,
 };
@@ -146,6 +148,7 @@ struct hclgevf_dev {
 
 	struct timer_list service_timer;
 	struct work_struct service_task;
+	struct work_struct rst_service_task;
 	struct work_struct mbx_service_task;
 
 	struct hclgevf_tqp *htqp;
@@ -165,4 +168,5 @@ void hclgevf_mbx_handler(struct hclgevf_dev *hdev);
 void hclgevf_update_link_status(struct hclgevf_dev *hdev, int link_state);
 void hclgevf_update_speed_duplex(struct hclgevf_dev *hdev, u32 speed,
 				 u8 duplex);
+void hclgevf_reset_task_schedule(struct hclgevf_dev *hdev);
 #endif
-- 
2.7.4

[PATCH net-next 3/9] net: hns3: Add VF Reset device state and its handling

[Salil Mehta]

This introduces the hclge device reset states of "requested" and
"pending" and also its handling in context to Reset Service Task.

Device gets into requested state because of any VF reset request
asserted from upper layers, for example due to watchdog timeout
expiration. Requested state would result in eventually forwarding
the VF reset request to PF which would actually reset the VF.

Device will get into pending state if:
1. VF receives the acknowledgement from PF for the VF reset
   request it originally sent to PF.
2. Reset Service Task detects that after asserting VF reset for
   certain times the data-path is not working and device then
   decides to assert full VF reset(this means also resetting the
   PCIe interface).
3. PF intimates the VF that it has undergone reset.
Pending state would result in VF to poll for hardware reset
completion status and then resetting the stack/enet layer, which
in turn means reinitializing the ring management/enet layer.

Note: we would be adding support of 3. later as a separate patch.
This decision should not affect VF reset as its event handling
is generic in nature.

Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
---
 drivers/net/ethernet/hisilicon/hns3/hnae3.h        |  1 +
 .../ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c  | 67 ++++++++++++++++++++--
 .../ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h  |  5 ++
 3 files changed, 68 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/hisilicon/hns3/hnae3.h b/drivers/net/ethernet/hisilicon/hns3/hnae3.h
index 56f9e650..37ec1b3 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hnae3.h
+++ b/drivers/net/ethernet/hisilicon/hns3/hnae3.h
@@ -119,6 +119,7 @@ enum hnae3_reset_notify_type {
 
 enum hnae3_reset_type {
 	HNAE3_VF_RESET,
+	HNAE3_VF_FULL_RESET,
 	HNAE3_FUNC_RESET,
 	HNAE3_CORE_RESET,
 	HNAE3_GLOBAL_RESET,
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
index cdb6e7a..0d204e2 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
@@ -840,7 +840,9 @@ static void hclgevf_reset_event(struct hnae3_handle *handle)
 
 	handle->reset_level = HNAE3_VF_RESET;
 
-	/* request VF reset here. Code added later */
+	/* reset of this VF requested */
+	set_bit(HCLGEVF_RESET_REQUESTED, &hdev->reset_state);
+	hclgevf_reset_task_schedule(hdev);
 
 	handle->last_reset_time = jiffies;
 }
@@ -889,6 +891,12 @@ static void hclgevf_task_schedule(struct hclgevf_dev *hdev)
 		schedule_work(&hdev->service_task);
 }
 
+static void hclgevf_deferred_task_schedule(struct hclgevf_dev *hdev)
+{
+	if (test_bit(HCLGEVF_RESET_PENDING, &hdev->reset_state))
+		hclgevf_reset_task_schedule(hdev);
+}
+
 static void hclgevf_service_timer(struct timer_list *t)
 {
 	struct hclgevf_dev *hdev = from_timer(hdev, t, service_timer);
@@ -908,10 +916,57 @@ static void hclgevf_reset_service_task(struct work_struct *work)
 
 	clear_bit(HCLGEVF_STATE_RST_SERVICE_SCHED, &hdev->state);
 
-	/* body of the reset service task will constitute of hclge device
-	 * reset state handling. This code shall be added subsequently in
-	 * next patches.
-	 */
+	if (test_and_clear_bit(HCLGEVF_RESET_PENDING,
+			       &hdev->reset_state)) {
+		/* PF has initmated that it is about to reset the hardware.
+		 * We now have to poll & check if harware has actually completed
+		 * the reset sequence. On hardware reset completion, VF needs to
+		 * reset the client and ae device.
+		 */
+		hdev->reset_attempts = 0;
+
+		/* code to check/wait for hardware reset completion and the
+		 * further initiating software stack reset would be added here
+		 */
+
+	} else if (test_and_clear_bit(HCLGEVF_RESET_REQUESTED,
+				      &hdev->reset_state)) {
+		/* we could be here when either of below happens:
+		 * 1. reset was initiated due to watchdog timeout due to
+		 *    a. IMP was earlier reset and our TX got choked down and
+		 *       which resulted in watchdog reacting and inducing VF
+		 *       reset. This also means our cmdq would be unreliable.
+		 *    b. problem in TX due to other lower layer(example link
+		 *       layer not functioning properly etc.)
+		 * 2. VF reset might have been initiated due to some config
+		 *    change.
+		 *
+		 * NOTE: Theres no clear way to detect above cases than to react
+		 * to the response of PF for this reset request. PF will ack the
+		 * 1b and 2. cases but we will not get any intimation about 1a
+		 * from PF as cmdq would be in unreliable state i.e. mailbox
+		 * communication between PF and VF would be broken.
+		 */
+
+		/* if we are never geting into pending state it means either:
+		 * 1. PF is not receiving our request which could be due to IMP
+		 *    reset
+		 * 2. PF is screwed
+		 * We cannot do much for 2. but to check first we can try reset
+		 * our PCIe + stack and see if it alleviates the problem.
+		 */
+		if (hdev->reset_attempts > 3) {
+			/* prepare for full reset of stack + pcie interface */
+			hdev->nic.reset_level = HNAE3_VF_FULL_RESET;
+
+			/* "defer" schedule the reset task again */
+			set_bit(HCLGEVF_RESET_PENDING, &hdev->reset_state);
+		} else {
+			hdev->reset_attempts++;
+
+			/* request PF for resetting this VF via mailbox */
+		}
+	}
 
 	clear_bit(HCLGEVF_STATE_RST_HANDLING, &hdev->state);
 }
@@ -943,6 +998,8 @@ static void hclgevf_service_task(struct work_struct *work)
 	 */
 	hclgevf_request_link_info(hdev);
 
+	hclgevf_deferred_task_schedule(hdev);
+
 	clear_bit(HCLGEVF_STATE_SERVICE_SCHED, &hdev->state);
 }
 
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h
index 8b5fa67..1c9cf87 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h
@@ -124,6 +124,11 @@ struct hclgevf_dev {
 	struct hclgevf_rss_cfg rss_cfg;
 	unsigned long state;
 
+#define HCLGEVF_RESET_REQUESTED		0
+#define HCLGEVF_RESET_PENDING		1
+	unsigned long reset_state;	/* requested, pending */
+	u32 reset_attempts;
+
 	u32 fw_version;
 	u16 num_tqps;		/* num task queue pairs of this PF */
 
-- 
2.7.4

[PATCH net-next 4/9] net: hns3: Add support to request VF Reset to PF

[Salil Mehta]

VF driver depends upon PF to eventually reset the hardware. This
request is made using the mailbox command. This patch adds the
required function to acheive above.

Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
---
 .../net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
index 0d204e2..b648311 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
@@ -832,6 +832,20 @@ static void hclgevf_reset_tqp(struct hnae3_handle *handle, u16 queue_id)
 			     2, true, NULL, 0);
 }
 
+static int hclgevf_do_reset(struct hclgevf_dev *hdev)
+{
+	int status;
+	u8 respmsg;
+
+	status = hclgevf_send_mbx_msg(hdev, HCLGE_MBX_RESET, 0, NULL,
+				      0, false, &respmsg, sizeof(u8));
+	if (status)
+		dev_err(&hdev->pdev->dev,
+			"VF reset request to PF failed(=%d)\n", status);
+
+	return status;
+}
+
 static void hclgevf_reset_event(struct hnae3_handle *handle)
 {
 	struct hclgevf_dev *hdev = hclgevf_ae_get_hdev(handle);
@@ -910,6 +924,7 @@ static void hclgevf_reset_service_task(struct work_struct *work)
 {
 	struct hclgevf_dev *hdev =
 		container_of(work, struct hclgevf_dev, rst_service_task);
+	int ret;
 
 	if (test_and_set_bit(HCLGEVF_STATE_RST_HANDLING, &hdev->state))
 		return;
@@ -965,6 +980,10 @@ static void hclgevf_reset_service_task(struct work_struct *work)
 			hdev->reset_attempts++;
 
 			/* request PF for resetting this VF via mailbox */
+			ret = hclgevf_do_reset(hdev);
+			if (ret)
+				dev_warn(&hdev->pdev->dev,
+					 "VF rst fail, stack will call\n");
 		}
 	}
 
-- 
2.7.4

[PATCH net-next 5/9] net: hns3: Add support to reset the enet/ring mgmt layer

[Salil Mehta]

After VF driver knows that hardware reset has been performed
successfully, it should proceed ahead and reset the enet layer.
This primarily consists of bringing down interface, clearing
TX/RX rings, disassociating vectors from ring etc.

Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
---
 .../ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c  | 103 ++++++++++++++++++++-
 .../ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h  |   3 +
 2 files changed, 102 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
index b648311..bd45b11 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
@@ -2,6 +2,7 @@
 // Copyright (c) 2016-2017 Hisilicon Limited.
 
 #include <linux/etherdevice.h>
+#include <net/rtnetlink.h>
 #include "hclgevf_cmd.h"
 #include "hclgevf_main.h"
 #include "hclge_mbx.h"
@@ -832,6 +833,101 @@ static void hclgevf_reset_tqp(struct hnae3_handle *handle, u16 queue_id)
 			     2, true, NULL, 0);
 }
 
+static int hclgevf_notify_client(struct hclgevf_dev *hdev,
+				 enum hnae3_reset_notify_type type)
+{
+	struct hnae3_client *client = hdev->nic_client;
+	struct hnae3_handle *handle = &hdev->nic;
+
+	if (!client->ops->reset_notify)
+		return -EOPNOTSUPP;
+
+	return client->ops->reset_notify(handle, type);
+}
+
+static int hclgevf_reset_wait(struct hclgevf_dev *hdev)
+{
+#define HCLGEVF_RESET_WAIT_MS	500
+#define HCLGEVF_RESET_WAIT_CNT	20
+	u32 val, cnt = 0;
+
+	/* wait to check the hardware reset completion status */
+	val = hclgevf_read_dev(&hdev->hw, HCLGEVF_FUN_RST_ING);
+	while (hnae_get_bit(val, HCLGEVF_FUN_RST_ING_B) &&
+			    (cnt < HCLGEVF_RESET_WAIT_CNT)) {
+		msleep(HCLGEVF_RESET_WAIT_MS);
+		val = hclgevf_read_dev(&hdev->hw, HCLGEVF_FUN_RST_ING);
+		cnt++;
+	}
+
+	/* hardware completion status should be available by this time */
+	if (cnt >= HCLGEVF_RESET_WAIT_CNT) {
+		dev_warn(&hdev->pdev->dev,
+			 "could'nt get reset done status from h/w, timeout!\n");
+		return -EBUSY;
+	}
+
+	/* we will wait a bit more to let reset of the stack to complete. This
+	 * might happen in case reset assertion was made by PF. Yes, this also
+	 * means we might end up waiting bit more even for VF reset.
+	 */
+	msleep(5000);
+
+	return 0;
+}
+
+static int hclgevf_reset_stack(struct hclgevf_dev *hdev)
+{
+	/* uninitialize the nic client */
+	hclgevf_notify_client(hdev, HNAE3_UNINIT_CLIENT);
+
+	/* re-initialize the hclge device - add code here */
+
+	/* bring up the nic client again */
+	hclgevf_notify_client(hdev, HNAE3_INIT_CLIENT);
+
+	return 0;
+}
+
+static int hclgevf_reset(struct hclgevf_dev *hdev)
+{
+	int ret;
+
+	rtnl_lock();
+
+	/* bring down the nic to stop any ongoing TX/RX */
+	hclgevf_notify_client(hdev, HNAE3_DOWN_CLIENT);
+
+	/* check if VF could successfully fetch the hardware reset completion
+	 * status from the hardware
+	 */
+	ret = hclgevf_reset_wait(hdev);
+	if (ret) {
+		/* can't do much in this situation, will disable VF */
+		dev_err(&hdev->pdev->dev,
+			"VF failed(=%d) to fetch H/W reset completion status\n",
+			ret);
+
+		dev_warn(&hdev->pdev->dev, "VF reset failed, disabling VF!\n");
+		hclgevf_notify_client(hdev, HNAE3_UNINIT_CLIENT);
+
+		rtnl_unlock();
+		return ret;
+	}
+
+	/* now, re-initialize the nic client and ae device*/
+	ret = hclgevf_reset_stack(hdev);
+	if (ret)
+		dev_err(&hdev->pdev->dev, "failed to reset VF stack\n");
+
+	/* bring up the nic to enable TX/RX again */
+	hclgevf_notify_client(hdev, HNAE3_UP_CLIENT);
+
+	rtnl_unlock();
+
+	return ret;
+}
+
 static int hclgevf_do_reset(struct hclgevf_dev *hdev)
 {
 	int status;
@@ -940,10 +1036,9 @@ static void hclgevf_reset_service_task(struct work_struct *work)
 		 */
 		hdev->reset_attempts = 0;
 
-		/* code to check/wait for hardware reset completion and the
-		 * further initiating software stack reset would be added here
-		 */
-
+		ret = hclgevf_reset(hdev);
+		if (ret)
+			dev_err(&hdev->pdev->dev, "VF stack reset failed.\n");
 	} else if (test_and_clear_bit(HCLGEVF_RESET_REQUESTED,
 				      &hdev->reset_state)) {
 		/* we could be here when either of below happens:
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h
index 1c9cf87..afdb15d 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h
@@ -34,6 +34,9 @@
 #define HCLGEVF_VECTOR0_RX_CMDQ_INT_B	1
 
 #define HCLGEVF_TQP_RESET_TRY_TIMES	10
+/* Reset related Registers */
+#define HCLGEVF_FUN_RST_ING		0x20C00
+#define HCLGEVF_FUN_RST_ING_B		0
 
 #define HCLGEVF_RSS_IND_TBL_SIZE		512
 #define HCLGEVF_RSS_SET_BITMAP_MSK	0xffff
-- 
2.7.4

[PATCH net-next 6/9] net: hns3: Add support to re-initialize the hclge device

[Salil Mehta]

After the hardware reset we should re-fetch the configuration from
PF like queue info and tc info. This might have impact on allocations
made like that of TQPs. Hence, we should release all such allocations
and re-allocate fresh according to new fetched configuration after
reset.

Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
---
 .../ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c  | 106 ++++++++++++++++++---
 .../ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h  |  14 +++
 2 files changed, 106 insertions(+), 14 deletions(-)

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
index bd45b11..6dd7561 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
@@ -10,6 +10,8 @@
 
 #define HCLGEVF_NAME	"hclgevf"
 
+static int hclgevf_init_hdev(struct hclgevf_dev *hdev);
+static void hclgevf_uninit_hdev(struct hclgevf_dev *hdev);
 static struct hnae3_ae_algo ae_algovf;
 
 static const struct pci_device_id ae_algovf_pci_tbl[] = {
@@ -209,6 +211,12 @@ static int hclgevf_alloc_tqps(struct hclgevf_dev *hdev)
 	struct hclgevf_tqp *tqp;
 	int i;
 
+	/* if this is on going reset then we need to re-allocate the TPQs
+	 * since we cannot assume we would get same number of TPQs back from PF
+	 */
+	if (hclgevf_dev_ongoing_reset(hdev))
+		devm_kfree(&hdev->pdev->dev, hdev->htqp);
+
 	hdev->htqp = devm_kcalloc(&hdev->pdev->dev, hdev->num_tqps,
 				  sizeof(struct hclgevf_tqp), GFP_KERNEL);
 	if (!hdev->htqp)
@@ -252,6 +260,12 @@ static int hclgevf_knic_setup(struct hclgevf_dev *hdev)
 	new_tqps = kinfo->rss_size * kinfo->num_tc;
 	kinfo->num_tqps = min(new_tqps, hdev->num_tqps);
 
+	/* if this is on going reset then we need to re-allocate the hnae queues
+	 * as well since number of TPQs from PF might have changed.
+	 */
+	if (hclgevf_dev_ongoing_reset(hdev))
+		devm_kfree(&hdev->pdev->dev, kinfo->tqp);
+
 	kinfo->tqp = devm_kcalloc(&hdev->pdev->dev, kinfo->num_tqps,
 				  sizeof(struct hnae3_queue *), GFP_KERNEL);
 	if (!kinfo->tqp)
@@ -878,10 +892,18 @@ static int hclgevf_reset_wait(struct hclgevf_dev *hdev)
 
 static int hclgevf_reset_stack(struct hclgevf_dev *hdev)
 {
+	int ret;
+
 	/* uninitialize the nic client */
 	hclgevf_notify_client(hdev, HNAE3_UNINIT_CLIENT);
 
-	/* re-initialize the hclge device - add code here */
+	/* re-initialize the hclge device */
+	ret = hclgevf_init_hdev(hdev);
+	if (ret) {
+		dev_err(&hdev->pdev->dev,
+			"hclge device re-init failed, VF is disabled!\n");
+		return ret;
+	}
 
 	/* bring up the nic client again */
 	hclgevf_notify_client(hdev, HNAE3_INIT_CLIENT);
@@ -1179,6 +1201,22 @@ static int hclgevf_configure(struct hclgevf_dev *hdev)
 	return hclgevf_get_tc_info(hdev);
 }
 
+static int hclgevf_alloc_hdev(struct hnae3_ae_dev *ae_dev)
+{
+	struct pci_dev *pdev = ae_dev->pdev;
+	struct hclgevf_dev *hdev = ae_dev->priv;
+
+	hdev = devm_kzalloc(&pdev->dev, sizeof(*hdev), GFP_KERNEL);
+	if (!hdev)
+		return -ENOMEM;
+
+	hdev->pdev = pdev;
+	hdev->ae_dev = ae_dev;
+	ae_dev->priv = hdev;
+
+	return 0;
+}
+
 static int hclgevf_init_roce_base_info(struct hclgevf_dev *hdev)
 {
 	struct hnae3_handle *roce = &hdev->roce;
@@ -1284,6 +1322,10 @@ static void hclgevf_ae_stop(struct hnae3_handle *handle)
 
 static void hclgevf_state_init(struct hclgevf_dev *hdev)
 {
+	/* if this is on going reset then skip this initialization */
+	if (hclgevf_dev_ongoing_reset(hdev))
+		return;
+
 	/* setup tasks for the MBX */
 	INIT_WORK(&hdev->mbx_service_task, hclgevf_mailbox_service_task);
 	clear_bit(HCLGEVF_STATE_MBX_SERVICE_SCHED, &hdev->state);
@@ -1325,6 +1367,10 @@ static int hclgevf_init_msi(struct hclgevf_dev *hdev)
 	int vectors;
 	int i;
 
+	/* if this is on going reset then skip this initialization */
+	if (hclgevf_dev_ongoing_reset(hdev))
+		return 0;
+
 	hdev->num_msi = HCLGEVF_MAX_VF_VECTOR_NUM;
 
 	vectors = pci_alloc_irq_vectors(pdev, 1, hdev->num_msi,
@@ -1375,6 +1421,10 @@ static int hclgevf_misc_irq_init(struct hclgevf_dev *hdev)
 {
 	int ret = 0;
 
+	/* if this is on going reset then skip this initialization */
+	if (hclgevf_dev_ongoing_reset(hdev))
+		return 0;
+
 	hclgevf_get_misc_vector(hdev);
 
 	ret = request_irq(hdev->misc_vector.vector_irq, hclgevf_misc_irq_handle,
@@ -1485,6 +1535,14 @@ static int hclgevf_pci_init(struct hclgevf_dev *hdev)
 	struct hclgevf_hw *hw;
 	int ret;
 
+	/* check if we need to skip initialization of pci. This will happen if
+	 * device is undergoing VF reset. Otherwise, we would need to
+	 * re-initialize pci interface again i.e. when device is not going
+	 * through *any* reset or actually undergoing full reset.
+	 */
+	if (hclgevf_dev_ongoing_reset(hdev))
+		return 0;
+
 	ret = pci_enable_device(pdev);
 	if (ret) {
 		dev_err(&pdev->dev, "failed to enable PCI device\n");
@@ -1536,19 +1594,16 @@ static void hclgevf_pci_uninit(struct hclgevf_dev *hdev)
 	pci_set_drvdata(pdev, NULL);
 }
 
-static int hclgevf_init_ae_dev(struct hnae3_ae_dev *ae_dev)
+static int hclgevf_init_hdev(struct hclgevf_dev *hdev)
 {
-	struct pci_dev *pdev = ae_dev->pdev;
-	struct hclgevf_dev *hdev;
+	struct pci_dev *pdev = hdev->pdev;
 	int ret;
 
-	hdev = devm_kzalloc(&pdev->dev, sizeof(*hdev), GFP_KERNEL);
-	if (!hdev)
-		return -ENOMEM;
-
-	hdev->pdev = pdev;
-	hdev->ae_dev = ae_dev;
-	ae_dev->priv = hdev;
+	/* check if device is on-going full reset(i.e. pcie as well) */
+	if (hclgevf_dev_ongoing_full_reset(hdev)) {
+		dev_warn(&pdev->dev, "device is going full reset\n");
+		hclgevf_uninit_hdev(hdev);
+	}
 
 	ret = hclgevf_pci_init(hdev);
 	if (ret) {
@@ -1633,15 +1688,38 @@ static int hclgevf_init_ae_dev(struct hnae3_ae_dev *ae_dev)
 	return ret;
 }
 
-static void hclgevf_uninit_ae_dev(struct hnae3_ae_dev *ae_dev)
+static void hclgevf_uninit_hdev(struct hclgevf_dev *hdev)
 {
-	struct hclgevf_dev *hdev = ae_dev->priv;
-
 	hclgevf_cmd_uninit(hdev);
 	hclgevf_misc_irq_uninit(hdev);
 	hclgevf_state_uninit(hdev);
 	hclgevf_uninit_msi(hdev);
 	hclgevf_pci_uninit(hdev);
+}
+
+static int hclgevf_init_ae_dev(struct hnae3_ae_dev *ae_dev)
+{
+	struct pci_dev *pdev = ae_dev->pdev;
+	int ret;
+
+	ret = hclgevf_alloc_hdev(ae_dev);
+	if (ret) {
+		dev_err(&pdev->dev, "hclge device allocation failed\n");
+		return ret;
+	}
+
+	ret = hclgevf_init_hdev(ae_dev->priv);
+	if (ret)
+		dev_err(&pdev->dev, "hclge device initialization failed\n");
+
+	return ret;
+}
+
+static void hclgevf_uninit_ae_dev(struct hnae3_ae_dev *ae_dev)
+{
+	struct hclgevf_dev *hdev = ae_dev->priv;
+
+	hclgevf_uninit_hdev(hdev);
 	ae_dev->priv = NULL;
 }
 
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h
index afdb15d..8cdc602 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h
@@ -169,6 +169,20 @@ struct hclgevf_dev {
 	u32 flag;
 };
 
+static inline bool hclgevf_dev_ongoing_reset(struct hclgevf_dev *hdev)
+{
+	return (hdev &&
+		(test_bit(HCLGEVF_STATE_RST_HANDLING, &hdev->state)) &&
+		(hdev->nic.reset_level == HNAE3_VF_RESET));
+}
+
+static inline bool hclgevf_dev_ongoing_full_reset(struct hclgevf_dev *hdev)
+{
+	return (hdev &&
+		(test_bit(HCLGEVF_STATE_RST_HANDLING, &hdev->state)) &&
+		(hdev->nic.reset_level == HNAE3_VF_FULL_RESET));
+}
+
 int hclgevf_send_mbx_msg(struct hclgevf_dev *hdev, u16 code, u16 subcode,
 			 const u8 *msg_data, u8 msg_len, bool need_resp,
 			 u8 *resp_data, u16 resp_len);
-- 
2.7.4

[PATCH net-next 7/9] net: hns3: Changes to support ARQ(Asynchronous Receive Queue)

[Salil Mehta]

Current mailbox CRQ could consists of both synchronous and async
responses from the PF. Synchronous responses are time critical
and should be handed over to the waiting tasks/context as quickly
as possible otherwise timeout occurs.

Above problem gets accentuated if CRQ consists of even single
async message. Hence, it is important to have quick handling of
synchronous messages and maybe deferred handling of async messages
This patch introduces separate ARQ(async receive queues) for the
async messages. These messages are processed later with repsect
to mailbox task while synchronous messages still gets processed
in context to mailbox interrupt.

ARQ is important as VF reset introduces some new async messages
like MBX_ASSERTING_RESET which adds up to the presssure on the
responses for synchronousmessages and they timeout even more
quickly.

Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
---
 drivers/net/ethernet/hisilicon/hns3/hclge_mbx.h    | 15 ++++
 .../ethernet/hisilicon/hns3/hns3vf/hclgevf_cmd.c   |  6 ++
 .../ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c  | 16 +++--
 .../ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h  |  5 ++
 .../ethernet/hisilicon/hns3/hns3vf/hclgevf_mbx.c   | 83 +++++++++++++++++++---
 5 files changed, 111 insertions(+), 14 deletions(-)

diff --git a/drivers/net/ethernet/hisilicon/hns3/hclge_mbx.h b/drivers/net/ethernet/hisilicon/hns3/hclge_mbx.h
index e6e1d22..f3e90c2 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hclge_mbx.h
+++ b/drivers/net/ethernet/hisilicon/hns3/hclge_mbx.h
@@ -85,6 +85,21 @@ struct hclge_mbx_pf_to_vf_cmd {
 	u16 msg[8];
 };
 
+/* used by VF to store the received Async responses from PF */
+struct hclgevf_mbx_arq_ring {
+#define HCLGE_MBX_MAX_ARQ_MSG_SIZE	8
+#define HCLGE_MBX_MAX_ARQ_MSG_NUM	1024
+	struct hclgevf_dev *hdev;
+	u32 head;
+	u32 tail;
+	u32 count;
+	u16 msg_q[HCLGE_MBX_MAX_ARQ_MSG_NUM][HCLGE_MBX_MAX_ARQ_MSG_SIZE];
+};
+
 #define hclge_mbx_ring_ptr_move_crq(crq) \
 	(crq->next_to_use = (crq->next_to_use + 1) % crq->desc_num)
+#define hclge_mbx_tail_ptr_move_arq(arq) \
+	(arq.tail = (arq.tail + 1) % HCLGE_MBX_MAX_ARQ_MSG_SIZE)
+#define hclge_mbx_head_ptr_move_arq(arq) \
+		(arq.head = (arq.head + 1) % HCLGE_MBX_MAX_ARQ_MSG_SIZE)
 #endif
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_cmd.c b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_cmd.c
index 85985e7..1bbfe13 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_cmd.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_cmd.c
@@ -315,6 +315,12 @@ int hclgevf_cmd_init(struct hclgevf_dev *hdev)
 		goto err_csq;
 	}
 
+	/* initialize the pointers of async rx queue of mailbox */
+	hdev->arq.hdev = hdev;
+	hdev->arq.head = 0;
+	hdev->arq.tail = 0;
+	hdev->arq.count = 0;
+
 	/* get firmware version */
 	ret = hclgevf_cmd_query_firmware_version(&hdev->hw, &version);
 	if (ret) {
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
index 6dd7561..2b84264 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
@@ -1010,10 +1010,13 @@ void hclgevf_reset_task_schedule(struct hclgevf_dev *hdev)
 	}
 }
 
-static void hclgevf_mbx_task_schedule(struct hclgevf_dev *hdev)
+void hclgevf_mbx_task_schedule(struct hclgevf_dev *hdev)
 {
-	if (!test_and_set_bit(HCLGEVF_STATE_MBX_SERVICE_SCHED, &hdev->state))
+	if (!test_bit(HCLGEVF_STATE_MBX_SERVICE_SCHED, &hdev->state) &&
+	    !test_bit(HCLGEVF_STATE_MBX_HANDLING, &hdev->state)) {
+		set_bit(HCLGEVF_STATE_MBX_SERVICE_SCHED, &hdev->state);
 		schedule_work(&hdev->mbx_service_task);
+	}
 }
 
 static void hclgevf_task_schedule(struct hclgevf_dev *hdev)
@@ -1025,6 +1028,10 @@ static void hclgevf_task_schedule(struct hclgevf_dev *hdev)
 
 static void hclgevf_deferred_task_schedule(struct hclgevf_dev *hdev)
 {
+	/* if we have any pending mailbox event then schedule the mbx task */
+	if (hdev->mbx_event_pending)
+		hclgevf_mbx_task_schedule(hdev);
+
 	if (test_bit(HCLGEVF_RESET_PENDING, &hdev->reset_state))
 		hclgevf_reset_task_schedule(hdev);
 }
@@ -1118,7 +1125,7 @@ static void hclgevf_mailbox_service_task(struct work_struct *work)
 
 	clear_bit(HCLGEVF_STATE_MBX_SERVICE_SCHED, &hdev->state);
 
-	hclgevf_mbx_handler(hdev);
+	hclgevf_mbx_async_handler(hdev);
 
 	clear_bit(HCLGEVF_STATE_MBX_HANDLING, &hdev->state);
 }
@@ -1178,8 +1185,7 @@ static irqreturn_t hclgevf_misc_irq_handle(int irq, void *data)
 	if (!hclgevf_check_event_cause(hdev, &clearval))
 		goto skip_sched;
 
-	/* schedule the VF mailbox service task, if not already scheduled */
-	hclgevf_mbx_task_schedule(hdev);
+	hclgevf_mbx_handler(hdev);
 
 	hclgevf_clear_event_cause(hdev, clearval);
 
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h
index 8cdc602..a477a7c 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h
@@ -152,7 +152,9 @@ struct hclgevf_dev {
 	int *vector_irq;
 
 	bool accept_mta_mc; /* whether to accept mta filter multicast */
+	bool mbx_event_pending;
 	struct hclgevf_mbx_resp_status mbx_resp; /* mailbox response */
+	struct hclgevf_mbx_arq_ring arq; /* mailbox async rx queue */
 
 	struct timer_list service_timer;
 	struct work_struct service_task;
@@ -187,8 +189,11 @@ int hclgevf_send_mbx_msg(struct hclgevf_dev *hdev, u16 code, u16 subcode,
 			 const u8 *msg_data, u8 msg_len, bool need_resp,
 			 u8 *resp_data, u16 resp_len);
 void hclgevf_mbx_handler(struct hclgevf_dev *hdev);
+void hclgevf_mbx_async_handler(struct hclgevf_dev *hdev);
+
 void hclgevf_update_link_status(struct hclgevf_dev *hdev, int link_state);
 void hclgevf_update_speed_duplex(struct hclgevf_dev *hdev, u32 speed,
 				 u8 duplex);
 void hclgevf_reset_task_schedule(struct hclgevf_dev *hdev);
+void hclgevf_mbx_task_schedule(struct hclgevf_dev *hdev);
 #endif
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_mbx.c b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_mbx.c
index a63ed3a..7687911 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_mbx.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_mbx.c
@@ -132,9 +132,8 @@ void hclgevf_mbx_handler(struct hclgevf_dev *hdev)
 	struct hclge_mbx_pf_to_vf_cmd *req;
 	struct hclgevf_cmq_ring *crq;
 	struct hclgevf_desc *desc;
-	u16 link_status, flag;
-	u32 speed;
-	u8 duplex;
+	u16 *msg_q;
+	u16 flag;
 	u8 *temp;
 	int i;
 
@@ -146,6 +145,12 @@ void hclgevf_mbx_handler(struct hclgevf_dev *hdev)
 		desc = &crq->desc[crq->next_to_use];
 		req = (struct hclge_mbx_pf_to_vf_cmd *)desc->data;
 
+		/* synchronous messages are time critical and need preferential
+		 * treatment. Therefore, we need to acknowledge all the sync
+		 * responses as quickly as possible so that waiting tasks do not
+		 * timeout and simultaneously queue the async messages for later
+		 * prcessing in context of mailbox task i.e. the slow path.
+		 */
 		switch (req->msg[0]) {
 		case HCLGE_MBX_PF_VF_RESP:
 			if (resp->received_resp)
@@ -165,13 +170,30 @@ void hclgevf_mbx_handler(struct hclgevf_dev *hdev)
 			}
 			break;
 		case HCLGE_MBX_LINK_STAT_CHANGE:
-			link_status = le16_to_cpu(req->msg[1]);
-			memcpy(&speed, &req->msg[2], sizeof(speed));
-			duplex = (u8)le16_to_cpu(req->msg[4]);
+			/* set this mbx event as pending. This is required as we
+			 * might loose interrupt event when mbx task is busy
+			 * handling. This shall be cleared when mbx task just
+			 * enters handling state.
+			 */
+			hdev->mbx_event_pending = true;
 
-			/* update upper layer with new link link status */
-			hclgevf_update_link_status(hdev, link_status);
-			hclgevf_update_speed_duplex(hdev, speed, duplex);
+			/* we will drop the async msg if we find ARQ as full
+			 * and continue with next message
+			 */
+			if (hdev->arq.count >= HCLGE_MBX_MAX_ARQ_MSG_NUM) {
+				dev_warn(&hdev->pdev->dev,
+					 "Async Q full, dropping msg(%d)\n",
+					 req->msg[1]);
+				break;
+			}
+
+			/* tail the async message in arq */
+			msg_q = hdev->arq.msg_q[hdev->arq.tail];
+			memcpy(&msg_q[0], req->msg, HCLGE_MBX_MAX_ARQ_MSG_SIZE);
+			hclge_mbx_tail_ptr_move_arq(hdev->arq);
+			hdev->arq.count++;
+
+			hclgevf_mbx_task_schedule(hdev);
 
 			break;
 		default:
@@ -189,3 +211,46 @@ void hclgevf_mbx_handler(struct hclgevf_dev *hdev)
 	hclgevf_write_dev(&hdev->hw, HCLGEVF_NIC_CRQ_HEAD_REG,
 			  crq->next_to_use);
 }
+
+void hclgevf_mbx_async_handler(struct hclgevf_dev *hdev)
+{
+	u16 link_status;
+	u16 *msg_q;
+	u8 duplex;
+	u32 speed;
+	u32 tail;
+
+	/* we can safely clear it now as we are at start of the async message
+	 * processing
+	 */
+	hdev->mbx_event_pending = false;
+
+	tail = hdev->arq.tail;
+
+	/* process all the async queue messages */
+	while (tail != hdev->arq.head) {
+		msg_q = hdev->arq.msg_q[hdev->arq.head];
+
+		switch (msg_q[0]) {
+		case HCLGE_MBX_LINK_STAT_CHANGE:
+			link_status = le16_to_cpu(msg_q[1]);
+			memcpy(&speed, &msg_q[2], sizeof(speed));
+			duplex = (u8)le16_to_cpu(msg_q[4]);
+
+			/* update upper layer with new link link status */
+			hclgevf_update_link_status(hdev, link_status);
+			hclgevf_update_speed_duplex(hdev, speed, duplex);
+
+			break;
+		default:
+			dev_err(&hdev->pdev->dev,
+				"fetched unsupported(%d) message from arq\n",
+				msg_q[0]);
+			break;
+		}
+
+		hclge_mbx_head_ptr_move_arq(hdev->arq);
+		hdev->arq.count--;
+		msg_q = hdev->arq.msg_q[hdev->arq.head];
+	}
+}
-- 
2.7.4

[PATCH net-next 8/9] net: hns3: Add *Asserting Reset* mailbox message & handling in VF

[Salil Mehta]

Reset Asserting message is forwarded by PF to inform VF about
the hardware reset which is about to happen. This might be due
to the earlier VF reset request received by the PF or because PF
for any reason decides to undergo reset. This message results in
VF to go in pending state in which it polls the hardware to
complete the reset and then further resets/tears its own stack.

Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
---
 drivers/net/ethernet/hisilicon/hns3/hclge_mbx.h          |  1 +
 drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_mbx.c | 12 ++++++++++++
 2 files changed, 13 insertions(+)

diff --git a/drivers/net/ethernet/hisilicon/hns3/hclge_mbx.h b/drivers/net/ethernet/hisilicon/hns3/hclge_mbx.h
index f3e90c2..519e2bd 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hclge_mbx.h
+++ b/drivers/net/ethernet/hisilicon/hns3/hclge_mbx.h
@@ -11,6 +11,7 @@
 
 enum HCLGE_MBX_OPCODE {
 	HCLGE_MBX_RESET = 0x01,		/* (VF -> PF) assert reset */
+	HCLGE_MBX_ASSERTING_RESET,	/* (PF -> VF) PF is asserting reset*/
 	HCLGE_MBX_SET_UNICAST,		/* (VF -> PF) set UC addr */
 	HCLGE_MBX_SET_MULTICAST,	/* (VF -> PF) set MC addr */
 	HCLGE_MBX_SET_VLAN,		/* (VF -> PF) set VLAN */
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_mbx.c b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_mbx.c
index 7687911..a286184 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_mbx.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_mbx.c
@@ -170,6 +170,7 @@ void hclgevf_mbx_handler(struct hclgevf_dev *hdev)
 			}
 			break;
 		case HCLGE_MBX_LINK_STAT_CHANGE:
+		case HCLGE_MBX_ASSERTING_RESET:
 			/* set this mbx event as pending. This is required as we
 			 * might loose interrupt event when mbx task is busy
 			 * handling. This shall be cleared when mbx task just
@@ -242,6 +243,17 @@ void hclgevf_mbx_async_handler(struct hclgevf_dev *hdev)
 			hclgevf_update_speed_duplex(hdev, speed, duplex);
 
 			break;
+		case HCLGE_MBX_ASSERTING_RESET:
+			/* PF has asserted reset hence VF should go in pending
+			 * state and poll for the hardware reset status till it
+			 * has been completely reset. After this stack should
+			 * eventually be re-initialized.
+			 */
+			hdev->nic.reset_level = HNAE3_VF_RESET;
+			set_bit(HCLGEVF_RESET_PENDING, &hdev->reset_state);
+			hclgevf_reset_task_schedule(hdev);
+
+			break;
 		default:
 			dev_err(&hdev->pdev->dev,
 				"fetched unsupported(%d) message from arq\n",
-- 
2.7.4

[PATCH net-next 9/9] net: hns3: Changes required in PF mailbox to support VF reset

[Salil Mehta]

PF needs to assert the VF reset when it receives the request to
reset from VF. After receiving request PF ackknowledges the
request by replying back MBX_ASSERTING_RESET message to VF.
VF then goes to pending state and wait for hardware to complete
the reset.

This patch contains code to handle the received VF message, inform
the VF of assertion and reset the VF using cmdq interface.

Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
---
 .../ethernet/hisilicon/hns3/hns3pf/hclge_main.c    |  2 +-
 .../ethernet/hisilicon/hns3/hns3pf/hclge_main.h    |  1 +
 .../net/ethernet/hisilicon/hns3/hns3pf/hclge_mbx.c | 42 ++++++++++++++++++++++
 3 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
index a3e00da..bede411 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
@@ -2749,7 +2749,7 @@ static int hclge_reset_wait(struct hclge_dev *hdev)
 	return 0;
 }
 
-static int hclge_func_reset_cmd(struct hclge_dev *hdev, int func_id)
+int hclge_func_reset_cmd(struct hclge_dev *hdev, int func_id)
 {
 	struct hclge_desc desc;
 	struct hclge_reset_cmd *req = (struct hclge_reset_cmd *)desc.data;
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.h b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.h
index 8c14d10..0f4157e 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.h
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.h
@@ -657,4 +657,5 @@ void hclge_mbx_handler(struct hclge_dev *hdev);
 void hclge_reset_tqp(struct hnae3_handle *handle, u16 queue_id);
 void hclge_reset_vf_queue(struct hclge_vport *vport, u16 queue_id);
 int hclge_cfg_flowctrl(struct hclge_dev *hdev);
+int hclge_func_reset_cmd(struct hclge_dev *hdev, int func_id);
 #endif
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_mbx.c b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_mbx.c
index 949da0c..3901333 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_mbx.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_mbx.c
@@ -79,6 +79,18 @@ static int hclge_send_mbx_msg(struct hclge_vport *vport, u8 *msg, u16 msg_len,
 	return status;
 }
 
+int hclge_inform_reset_assert_to_vf(struct hclge_vport *vport)
+{
+	u8 msg_data[2];
+	u8 dest_vfid;
+
+	dest_vfid = (u8)vport->vport_id;
+
+	/* send this requested info to VF */
+	return hclge_send_mbx_msg(vport, msg_data, sizeof(u8),
+				  HCLGE_MBX_ASSERTING_RESET, dest_vfid);
+}
+
 static void hclge_free_vector_ring_chain(struct hnae3_ring_chain_node *head)
 {
 	struct hnae3_ring_chain_node *chain_tmp, *chain;
@@ -339,6 +351,33 @@ static void hclge_mbx_reset_vf_queue(struct hclge_vport *vport,
 	hclge_gen_resp_to_vf(vport, mbx_req, 0, NULL, 0);
 }
 
+static void hclge_reset_vf(struct hclge_vport *vport,
+			   struct hclge_mbx_vf_to_pf_cmd *mbx_req)
+{
+	struct hclge_dev *hdev = vport->back;
+	int ret;
+
+	dev_warn(&hdev->pdev->dev, "PF received VF reset request from VF %d!",
+		 mbx_req->mbx_src_vfid);
+
+	/* Acknowledge VF that PF is now about to assert the reset for the VF.
+	 * On receiving this message VF will get into pending state and will
+	 * start polling for the hardware reset completion status.
+	 */
+	ret = hclge_inform_reset_assert_to_vf(vport);
+	if (ret) {
+		dev_err(&hdev->pdev->dev,
+			"PF fail(%d) to inform VF(%d)of reset, reset failed!\n",
+			ret, vport->vport_id);
+		return;
+	}
+
+	dev_warn(&hdev->pdev->dev, "PF is now resetting VF %d.\n",
+		 mbx_req->mbx_src_vfid);
+	/* reset this virtual function */
+	hclge_func_reset_cmd(hdev, mbx_req->mbx_src_vfid);
+}
+
 void hclge_mbx_handler(struct hclge_dev *hdev)
 {
 	struct hclge_cmq_ring *crq = &hdev->hw.cmq.crq;
@@ -416,6 +455,9 @@ void hclge_mbx_handler(struct hclge_dev *hdev)
 		case HCLGE_MBX_QUEUE_RESET:
 			hclge_mbx_reset_vf_queue(vport, req);
 			break;
+		case HCLGE_MBX_RESET:
+			hclge_reset_vf(vport, req);
+			break;
 		default:
 			dev_err(&hdev->pdev->dev,
 				"un-supported mailbox message, code = %d\n",
-- 
2.7.4

Re: [PATCH net-next 0/9] Add support of VF Reset to HNS3 VF driver

[David Miller]

From: Salil Mehta <salil.mehta@huawei.com>
Date: Thu, 22 Mar 2018 14:28:51 +0000

> This patch-set adds the support of VF reset to the existing VF driver.
> VF Reset can be triggered due to TX watchdog firing  as a result of TX
> data-path not working. VF reset could also be a result of some internal
> configuration changes if that requires reset, or as a result of the
> PF/Core/Global/IMP(Integrated Management Processor) reset happened in
> the PF. 
> 
> Summary of Patches:
> * Watchdog timer trigger chnages are present in Patch 1.
> * Reset Service Task and related Event handling is present in Patches {2,3}
> * Changes to send reset request to PF, reset stack and re-initialization
>   of the hclge device is present in Patches {4,5,6}
> * Changes related to ARQ (Asynchronous Receive Queue) and its event handling
>   are present in Patches {7,8}
> * Changes required in PF to handle the VF Reset request and actually perform
>   hardware VF reset is there in Patch 9.
> 
> 
> NOTE: This patch depends upon "[PATCH net-next 00/11] fix some bugs for HNS3 driver"
> 	Link: https://lkml.org/lkml/2018/3/21/72

Series applied, thank you.

Please audit your usage of the various reset state bits.

In most places you do the correct atomic sequence by making use of
test_and_set_bit() and test_and_clear_bit().

But in some cases you do things like:

	if (!test_bit(X) && !test_bit(Y)) {
	...
		set_bit(Y);
	}

which is racy.