[RFC PATCH v3 0/5] scsi: ufs: Add Host Performance Booster Support

[RFC PATCH v3 0/5] scsi: ufs: Add Host Performance Booster Support

[Daejun Park]

Changelog:

v2 -> v3
1. Add checking input module parameter value.
2. Change base commit from 5.8/scsi-queue to 5.9/scsi-queue.
3. Cleanup for unused variables and label.

v1 -> v2
1. Change the full boilerplate text to SPDX style.
2. Adopt dynamic allocation for sub-region data structure.
3. Cleanup.

NAND flash memory-based storage devices use Flash Translation Layer (FTL)
to translate logical addresses of I/O requests to corresponding flash
memory addresses. Mobile storage devices typically have RAM with
constrained size, thus lack in memory to keep the whole mapping table.
Therefore, mapping tables are partially retrieved from NAND flash on
demand, causing random-read performance degradation.

To improve random read performance, JESD220-3 (HPB v1.0) proposes HPB
(Host Performance Booster) which uses host system memory as a cache for the
FTL mapping table. By using HPB, FTL data can be read from host memory
faster than from NAND flash memory. 

The current version only supports the DCM (device control mode).
This patch consists of 4 parts to support HPB feature.

1) UFS-feature layer
2) HPB probe and initialization process
3) READ -> HPB READ using cached map information
4) L2P (logical to physical) map management

The UFS-feature is an additional layer to avoid the structure in which the
UFS-core driver and the UFS-feature are entangled with each other in a 
single module.
By adding the layer, UFS-features composed of various combinations can be
supported. Also, even if a new feature is added, modification of the 
UFS-core driver can be minimized.

In the HPB probe and init process, the device information of the UFS is
queried. After checking supported features, the data structure for the HPB
is initialized according to the device information.

A read I/O in the active sub-region where the map is cached is changed to
HPB READ by the HPB module.

The HPB module manages the L2P map using information received from the
device. For active sub-region, the HPB module caches through ufshpb_map
request. For the in-active region, the HPB module discards the L2P map.
When a write I/O occurs in an active sub-region area, associated dirty
bitmap checked as dirty for preventing stale read.

HPB is shown to have a performance improvement of 58 - 67% for random read
workload. [1]

This series patches are based on the 5.9/scsi-queue branch.

[1]:
https://www.usenix.org/conference/hotstorage17/program/presentation/jeong

Daejun park (5):
 scsi: ufs: Add UFS feature related parameter
 scsi: ufs: Add UFS feature layer
 scsi: ufs: Introduce HPB module
 scsi: ufs: L2P map management for HPB read
 scsi: ufs: Prepare HPB read for cached sub-region
 
 drivers/scsi/ufs/Kconfig      |    9 +
 drivers/scsi/ufs/Makefile     |    3 +-
 drivers/scsi/ufs/ufs.h        |   12 +
 drivers/scsi/ufs/ufsfeature.c |  148 +++
 drivers/scsi/ufs/ufsfeature.h |   69 ++
 drivers/scsi/ufs/ufshcd.c     |   23 +-
 drivers/scsi/ufs/ufshcd.h     |    3 +
 drivers/scsi/ufs/ufshpb.c     | 1996 ++++++++++++++++++++++++++++++++++++
 drivers/scsi/ufs/ufshpb.h     |  234 +++++
 9 files changed, 2494 insertions(+), 3 deletions(-)
 created mode 100644 drivers/scsi/ufs/ufsfeature.c
 created mode 100644 drivers/scsi/ufs/ufsfeature.h
 created mode 100644 drivers/scsi/ufs/ufshpb.c
 created mode 100644 drivers/scsi/ufs/ufshpb.h

[RFC PATCH v3 1/5] scsi: ufs: Add UFS feature related parameter

[Daejun Park]

This is a patch for parameters to be used for UFS features layer and HPB
module.

Signed-off-by: Daejun Park <daejun7.park@samsung.com>
---
 drivers/scsi/ufs/ufs.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h
index f8ab16f30fdc..ae557b8d3eba 100644
--- a/drivers/scsi/ufs/ufs.h
+++ b/drivers/scsi/ufs/ufs.h
@@ -122,6 +122,7 @@ enum flag_idn {
 	QUERY_FLAG_IDN_WB_EN                            = 0x0E,
 	QUERY_FLAG_IDN_WB_BUFF_FLUSH_EN                 = 0x0F,
 	QUERY_FLAG_IDN_WB_BUFF_FLUSH_DURING_HIBERN8     = 0x10,
+	QUERY_FLAG_IDN_HPB_RESET                        = 0x11,
 };
 
 /* Attribute idn for Query requests */
@@ -195,6 +196,9 @@ enum unit_desc_param {
 	UNIT_DESC_PARAM_PHY_MEM_RSRC_CNT	= 0x18,
 	UNIT_DESC_PARAM_CTX_CAPABILITIES	= 0x20,
 	UNIT_DESC_PARAM_LARGE_UNIT_SIZE_M1	= 0x22,
+	UNIT_DESC_HPB_LU_MAX_ACTIVE_REGIONS	= 0x23,
+	UNIT_DESC_HPB_LU_PIN_REGION_START_OFFSET	= 0x25,
+	UNIT_DESC_HPB_LU_NUM_PIN_REGIONS	= 0x27,
 	UNIT_DESC_PARAM_WB_BUF_ALLOC_UNITS	= 0x29,
 };
 
@@ -235,6 +239,8 @@ enum device_desc_param {
 	DEVICE_DESC_PARAM_PSA_MAX_DATA		= 0x25,
 	DEVICE_DESC_PARAM_PSA_TMT		= 0x29,
 	DEVICE_DESC_PARAM_PRDCT_REV		= 0x2A,
+	DEVICE_DESC_PARAM_HPB_VER		= 0x40,
+	DEVICE_DESC_PARAM_HPB_CONTROL		= 0x42,
 	DEVICE_DESC_PARAM_EXT_UFS_FEATURE_SUP	= 0x4F,
 	DEVICE_DESC_PARAM_WB_PRESRV_USRSPC_EN	= 0x53,
 	DEVICE_DESC_PARAM_WB_TYPE		= 0x54,
@@ -283,6 +289,10 @@ enum geometry_desc_param {
 	GEOMETRY_DESC_PARAM_ENM4_MAX_NUM_UNITS	= 0x3E,
 	GEOMETRY_DESC_PARAM_ENM4_CAP_ADJ_FCTR	= 0x42,
 	GEOMETRY_DESC_PARAM_OPT_LOG_BLK_SIZE	= 0x44,
+	GEOMETRY_DESC_HPB_REGION_SIZE		= 0x48,
+	GEOMETRY_DESC_HPB_NUMBER_LU		= 0x49,
+	GEOMETRY_DESC_HPB_SUBREGION_SIZE	= 0x4A,
+	GEOMETRY_DESC_HPB_DEVICE_MAX_ACTIVE_REGIONS	= 0x4B,
 	GEOMETRY_DESC_PARAM_WB_MAX_ALLOC_UNITS	= 0x4F,
 	GEOMETRY_DESC_PARAM_WB_MAX_WB_LUNS	= 0x53,
 	GEOMETRY_DESC_PARAM_WB_BUFF_CAP_ADJ	= 0x54,
@@ -327,6 +337,7 @@ enum {
 
 /* Possible values for dExtendedUFSFeaturesSupport */
 enum {
+	UFS_DEV_HPB_SUPPORT		= BIT(7),
 	UFS_DEV_WRITE_BOOSTER_SUP	= BIT(8),
 };
 
@@ -537,6 +548,7 @@ struct ufs_dev_info {
 	u8 *model;
 	u16 wspecversion;
 	u32 clk_gating_wait_us;
+	u8 b_ufs_feature_sup;
 	u32 d_ext_ufs_feature_sup;
 	u8 b_wb_buffer_type;
 	u32 d_wb_alloc_units;

base-commit: 3145550a7f8b08356c8ff29feaa6c56aca12901d
-- 
2.17.1

[RFC PATCH v3 2/5] scsi: ufs: Add UFS-feature layer

[Daejun Park]

This patch is adding UFS feature layer to UFS core driver.

UFS Driver data structure (struct ufs_hba)
	│
┌--------------┐
│ UFS feature  │ <-- HPB module
│    layer     │ <-- other extended feature module
└--------------┘
Each extended UFS-Feature module has a bus of ufs-ext feature type.
The UFS feature layer manages common APIs used by each extended feature
module. The APIs are set of UFS Query requests and UFS Vendor commands
related to each extended feature module.

Other extended features can also be implemented using the proposed APIs.
For example, in Write Booster, "prep_fn" can be used to guarantee the
lifetime of UFS by updating the amount of write IO.
And reset/reset_host/suspend/resume can be used to manage the kernel task
for checking lifetime of UFS.

The following 6 callback functions have been added to "ufshcd.c".
prep_fn: called after construct upiu structure
reset: called after proving hba
reset_host: called before ufshcd_host_reset_and_restore
suspend: called before ufshcd_suspend
resume: called after ufshcd_resume
rsp_upiu: called in ufshcd_transfer_rsp_status with SAM_STAT_GOOD state

Signed-off-by: Daejun Park <daejun7.park@samsung.com>
---
 drivers/scsi/ufs/Makefile     |   2 +-
 drivers/scsi/ufs/ufsfeature.c | 148 ++++++++++++++++++++++++++++++++++
 drivers/scsi/ufs/ufsfeature.h |  69 ++++++++++++++++
 drivers/scsi/ufs/ufshcd.c     |  17 ++++
 drivers/scsi/ufs/ufshcd.h     |   3 +
 5 files changed, 238 insertions(+), 1 deletion(-)
 create mode 100644 drivers/scsi/ufs/ufsfeature.c
 create mode 100644 drivers/scsi/ufs/ufsfeature.h

diff --git a/drivers/scsi/ufs/Makefile b/drivers/scsi/ufs/Makefile
index f0c5b95ec9cc..433b871badfa 100644
--- a/drivers/scsi/ufs/Makefile
+++ b/drivers/scsi/ufs/Makefile
@@ -6,7 +6,7 @@ obj-$(CONFIG_SCSI_UFS_CDNS_PLATFORM) += cdns-pltfrm.o
 obj-$(CONFIG_SCSI_UFS_QCOM) += ufs-qcom.o
 obj-$(CONFIG_SCSI_UFS_EXYNOS) += ufs-exynos.o
 obj-$(CONFIG_SCSI_UFSHCD) += ufshcd-core.o
-ufshcd-core-y				+= ufshcd.o ufs-sysfs.o
+ufshcd-core-y				+= ufshcd.o ufs-sysfs.o ufsfeature.o
 ufshcd-core-$(CONFIG_SCSI_UFS_BSG)	+= ufs_bsg.o
 obj-$(CONFIG_SCSI_UFSHCD_PCI) += ufshcd-pci.o
 obj-$(CONFIG_SCSI_UFSHCD_PLATFORM) += ufshcd-pltfrm.o
diff --git a/drivers/scsi/ufs/ufsfeature.c b/drivers/scsi/ufs/ufsfeature.c
new file mode 100644
index 000000000000..94c6be6babd3
--- /dev/null
+++ b/drivers/scsi/ufs/ufsfeature.c
@@ -0,0 +1,148 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Universal Flash Storage Feature Support
+ *
+ * Copyright (C) 2017-2018 Samsung Electronics Co., Ltd.
+ *
+ * Authors:
+ *	Yongmyung Lee <ymhungry.lee@samsung.com>
+ *	Jinyoung Choi <j-young.choi@samsung.com>
+ */
+
+#include "ufshcd.h"
+#include "ufsfeature.h"
+
+inline void ufsf_slave_configure(struct ufs_hba *hba,
+				 struct scsi_device *sdev)
+{
+	/* skip well-known LU */
+	if (sdev->lun >= UFS_UPIU_MAX_UNIT_NUM_ID)
+		return;
+
+	if (!(hba->dev_info.b_ufs_feature_sup & UFS_DEV_HPB_SUPPORT))
+		return;
+
+	atomic_inc(&hba->ufsf.slave_conf_cnt);
+
+	wake_up(&hba->ufsf.sdev_wait);
+}
+
+inline void ufsf_ops_prep_fn(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
+{
+	struct ufshpb_driver *ufshpb_drv;
+
+	ufshpb_drv = dev_get_drvdata(&hba->ufsf.hpb_dev);
+
+	if (ufshpb_drv && ufshpb_drv->ufshpb_ops.prep_fn)
+		ufshpb_drv->ufshpb_ops.prep_fn(hba, lrbp);
+}
+
+inline void ufsf_ops_rsp_upiu(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
+{
+	struct ufshpb_driver *ufshpb_drv;
+
+	ufshpb_drv = dev_get_drvdata(&hba->ufsf.hpb_dev);
+
+	if (ufshpb_drv && ufshpb_drv->ufshpb_ops.rsp_upiu)
+		ufshpb_drv->ufshpb_ops.rsp_upiu(hba, lrbp);
+}
+
+inline void ufsf_ops_reset_host(struct ufs_hba *hba)
+{
+	struct ufshpb_driver *ufshpb_drv;
+
+	ufshpb_drv = dev_get_drvdata(&hba->ufsf.hpb_dev);
+
+	if (ufshpb_drv && ufshpb_drv->ufshpb_ops.reset_host)
+		ufshpb_drv->ufshpb_ops.reset_host(hba);
+}
+
+inline void ufsf_ops_reset(struct ufs_hba *hba)
+{
+	struct ufshpb_driver *ufshpb_drv;
+
+	ufshpb_drv = dev_get_drvdata(&hba->ufsf.hpb_dev);
+
+	if (ufshpb_drv && ufshpb_drv->ufshpb_ops.reset)
+		ufshpb_drv->ufshpb_ops.reset(hba);
+}
+
+inline void ufsf_ops_suspend(struct ufs_hba *hba)
+{
+	struct ufshpb_driver *ufshpb_drv;
+
+	ufshpb_drv = dev_get_drvdata(&hba->ufsf.hpb_dev);
+
+	if (ufshpb_drv && ufshpb_drv->ufshpb_ops.suspend)
+		ufshpb_drv->ufshpb_ops.suspend(hba);
+}
+
+inline void ufsf_ops_resume(struct ufs_hba *hba)
+{
+	struct ufshpb_driver *ufshpb_drv;
+
+	ufshpb_drv = dev_get_drvdata(&hba->ufsf.hpb_dev);
+
+	if (ufshpb_drv && ufshpb_drv->ufshpb_ops.resume)
+		ufshpb_drv->ufshpb_ops.resume(hba);
+}
+
+struct device_type ufshpb_dev_type = {
+	.name = "ufshpb_device"
+};
+EXPORT_SYMBOL(ufshpb_dev_type);
+
+static int ufsf_bus_match(struct device *dev,
+			 struct device_driver *gendrv)
+{
+	if (dev->type == &ufshpb_dev_type)
+		return 1;
+
+	return 0;
+}
+
+struct bus_type ufsf_bus_type = {
+	.name = "ufsf_bus",
+	.match = ufsf_bus_match,
+};
+EXPORT_SYMBOL(ufsf_bus_type);
+
+static void ufsf_dev_release(struct device *dev)
+{
+	put_device(dev->parent);
+}
+
+void ufsf_scan_features(struct ufs_hba *hba)
+{
+	int ret;
+
+	init_waitqueue_head(&hba->ufsf.sdev_wait);
+	atomic_set(&hba->ufsf.slave_conf_cnt, 0);
+
+	if (hba->dev_info.wspecversion >= HPB_SUPPORTED_VERSION &&
+	    (hba->dev_info.b_ufs_feature_sup & UFS_DEV_HPB_SUPPORT)) {
+		device_initialize(&hba->ufsf.hpb_dev);
+
+		hba->ufsf.hpb_dev.bus = &ufsf_bus_type;
+		hba->ufsf.hpb_dev.type = &ufshpb_dev_type;
+		hba->ufsf.hpb_dev.parent = get_device(hba->dev);
+		hba->ufsf.hpb_dev.release = ufsf_dev_release;
+
+		dev_set_name(&hba->ufsf.hpb_dev, "ufshpb");
+		ret = device_add(&hba->ufsf.hpb_dev);
+		if (ret)
+			dev_warn(hba->dev, "ufshpb: failed to add device\n");
+	}
+}
+
+static int __init ufsf_init(void)
+{
+	int ret;
+
+	ret = bus_register(&ufsf_bus_type);
+	if (ret)
+		pr_err("%s bus_register failed\n", __func__);
+
+	return ret;
+}
+device_initcall(ufsf_init);
diff --git a/drivers/scsi/ufs/ufsfeature.h b/drivers/scsi/ufs/ufsfeature.h
new file mode 100644
index 000000000000..1822d9d8e745
--- /dev/null
+++ b/drivers/scsi/ufs/ufsfeature.h
@@ -0,0 +1,69 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Universal Flash Storage Feature Support
+ *
+ * Copyright (C) 2017-2018 Samsung Electronics Co., Ltd.
+ *
+ * Authors:
+ *	Yongmyung Lee <ymhungry.lee@samsung.com>
+ *	Jinyoung Choi <j-young.choi@samsung.com>
+ */
+
+#ifndef _UFSFEATURE_H_
+#define _UFSFEATURE_H_
+
+#define HPB_SUPPORTED_VERSION			0x0310
+
+struct ufs_hba;
+struct ufshcd_lrb;
+
+/**
+ * struct ufsf_operation - UFS feature specific callbacks
+ * @prep_fn: called after construct upiu structure. The prep_fn should work
+ *	     properly even if it processes the same SCSI command multiple
+ *	     times by requeuing.
+ * @reset: called after probing hba
+ * @reset_host: called before ufshcd_host_reset_and_restore
+ * @suspend: called before ufshcd_suspend
+ * @resume: called after ufshcd_resume
+ * @rsp_upiu: called in ufshcd_transfer_rsp_status with SAM_STAT_GOOD state
+ */
+struct ufsf_operation {
+	void (*prep_fn)(struct ufs_hba *hba, struct ufshcd_lrb *lrbp);
+	void (*reset)(struct ufs_hba *hba);
+	void (*reset_host)(struct ufs_hba *hba);
+	void (*suspend)(struct ufs_hba *hba);
+	void (*resume)(struct ufs_hba *hba);
+	void (*rsp_upiu)(struct ufs_hba *hba, struct ufshcd_lrb *lrbp);
+};
+
+struct ufshpb_driver {
+	struct device_driver drv;
+	struct list_head lh_hpb_lu;
+
+	struct ufsf_operation ufshpb_ops;
+
+	/* memory management */
+	struct kmem_cache *ufshpb_mctx_cache;
+	mempool_t *ufshpb_mctx_pool;
+	mempool_t *ufshpb_page_pool;
+
+	struct workqueue_struct *ufshpb_wq;
+};
+
+struct ufsf_feature_info {
+	atomic_t slave_conf_cnt;
+	wait_queue_head_t sdev_wait;
+	struct device hpb_dev;
+};
+
+void ufsf_slave_configure(struct ufs_hba *hba, struct scsi_device *sdev);
+void ufsf_scan_features(struct ufs_hba *hba);
+void ufsf_ops_prep_fn(struct ufs_hba *hba, struct ufshcd_lrb *lrbp);
+void ufsf_ops_rsp_upiu(struct ufs_hba *hba, struct ufshcd_lrb *lrbp);
+void ufsf_ops_reset_host(struct ufs_hba *hba);
+void ufsf_ops_reset(struct ufs_hba *hba);
+void ufsf_ops_suspend(struct ufs_hba *hba);
+void ufsf_ops_resume(struct ufs_hba *hba);
+
+#endif /* End of Header */
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 52abe82a1166..082dfca8e237 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -2533,6 +2533,8 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
 
 	ufshcd_comp_scsi_upiu(hba, lrbp);
 
+	ufsf_ops_prep_fn(hba, lrbp);
+
 	err = ufshcd_map_sg(hba, lrbp);
 	if (err) {
 		lrbp->cmd = NULL;
@@ -4665,6 +4667,8 @@ static int ufshcd_slave_configure(struct scsi_device *sdev)
 	struct ufs_hba *hba = shost_priv(sdev->host);
 	struct request_queue *q = sdev->request_queue;
 
+	ufsf_slave_configure(hba, sdev);
+
 	blk_queue_update_dma_pad(q, PRDT_DATA_BYTE_COUNT_PAD - 1);
 
 	if (ufshcd_is_rpm_autosuspend_allowed(hba))
@@ -4791,6 +4795,9 @@ ufshcd_transfer_rsp_status(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
 				 */
 				pm_runtime_get_noresume(hba->dev);
 			}
+
+			if (scsi_status == SAM_STAT_GOOD)
+				ufsf_ops_rsp_upiu(hba, lrbp);
 			break;
 		case UPIU_TRANSACTION_REJECT_UPIU:
 			/* TODO: handle Reject UPIU Response */
@@ -6539,6 +6546,8 @@ static int ufshcd_host_reset_and_restore(struct ufs_hba *hba)
 	 * Stop the host controller and complete the requests
 	 * cleared by h/w
 	 */
+	ufsf_ops_reset_host(hba);
+
 	ufshcd_hba_stop(hba);
 
 	spin_lock_irqsave(hba->host->host_lock, flags);
@@ -6963,6 +6972,7 @@ static int ufs_get_device_desc(struct ufs_hba *hba)
 	/* getting Specification Version in big endian format */
 	dev_info->wspecversion = desc_buf[DEVICE_DESC_PARAM_SPEC_VER] << 8 |
 				      desc_buf[DEVICE_DESC_PARAM_SPEC_VER + 1];
+	dev_info->b_ufs_feature_sup = desc_buf[DEVICE_DESC_PARAM_UFS_FEAT];
 
 	model_index = desc_buf[DEVICE_DESC_PARAM_PRDCT_NAME];
 
@@ -7340,6 +7350,7 @@ static int ufshcd_add_lus(struct ufs_hba *hba)
 	}
 
 	ufs_bsg_probe(hba);
+	ufsf_scan_features(hba);
 	scsi_scan_host(hba->host);
 	pm_runtime_put_sync(hba->dev);
 
@@ -7428,6 +7439,7 @@ static int ufshcd_probe_hba(struct ufs_hba *hba, bool async)
 	/* Enable Auto-Hibernate if configured */
 	ufshcd_auto_hibern8_enable(hba);
 
+	ufsf_ops_reset(hba);
 out:
 
 	trace_ufshcd_init(dev_name(hba->dev), ret,
@@ -8185,6 +8197,8 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 		req_link_state = UIC_LINK_OFF_STATE;
 	}
 
+	ufsf_ops_suspend(hba);
+
 	/*
 	 * If we can't transition into any of the low power modes
 	 * just gate the clocks.
@@ -8306,6 +8320,7 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 	hba->clk_gating.is_suspended = false;
 	hba->dev_info.b_rpm_dev_flush_capable = false;
 	ufshcd_release(hba);
+	ufsf_ops_resume(hba);
 out:
 	if (hba->dev_info.b_rpm_dev_flush_capable) {
 		schedule_delayed_work(&hba->rpm_dev_flush_recheck_work,
@@ -8402,6 +8417,8 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 	/* Enable Auto-Hibernate if configured */
 	ufshcd_auto_hibern8_enable(hba);
 
+	ufsf_ops_resume(hba);
+
 	if (hba->dev_info.b_rpm_dev_flush_capable) {
 		hba->dev_info.b_rpm_dev_flush_capable = false;
 		cancel_delayed_work(&hba->rpm_dev_flush_recheck_work);
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index c774012582b4..6fe5c9b3a0e7 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -46,6 +46,7 @@
 #include "ufs.h"
 #include "ufs_quirks.h"
 #include "ufshci.h"
+#include "ufsfeature.h"
 
 #define UFSHCD "ufshcd"
 #define UFSHCD_DRIVER_VERSION "0.2"
@@ -736,6 +737,8 @@ struct ufs_hba {
 	bool wb_buf_flush_enabled;
 	bool wb_enabled;
 	struct delayed_work rpm_dev_flush_recheck_work;
+
+	struct ufsf_feature_info ufsf;
 };
 
 /* Returns true if clocks can be gated. Otherwise false */
-- 
2.17.1

[RFC PATCH v3 3/5] scsi: ufs: Introduce HPB module

[Daejun Park]

This is a patch for the HPB module.
The HPB module queries UFS for device information during initialization.
We added the export symbol to two functions in ufshcd.c to initialize
the HPB module.

The HPB module can be loaded or built-in as needed.
The mininum size of the memory pool used in the HPB module is implemented
as a module parameter, so that it can be configurable by the user.

To gurantee a minimum memory pool size of 4MB:
$ insmod ufshpb.ko ufshpb_host_map_kbytes=4096

Signed-off-by: Daejun Park <daejun7.park@samsung.com>
---
 drivers/scsi/ufs/Kconfig  |   9 +
 drivers/scsi/ufs/Makefile |   1 +
 drivers/scsi/ufs/ufshcd.c |   2 +
 drivers/scsi/ufs/ufshpb.c | 777 ++++++++++++++++++++++++++++++++++++++
 drivers/scsi/ufs/ufshpb.h | 162 ++++++++
 5 files changed, 951 insertions(+)
 create mode 100644 drivers/scsi/ufs/ufshpb.c
 create mode 100644 drivers/scsi/ufs/ufshpb.h

diff --git a/drivers/scsi/ufs/Kconfig b/drivers/scsi/ufs/Kconfig
index 8cd90262784d..588f75fc8c0d 100644
--- a/drivers/scsi/ufs/Kconfig
+++ b/drivers/scsi/ufs/Kconfig
@@ -172,3 +172,12 @@ config SCSI_UFS_EXYNOS
 
 	  Select this if you have UFS host controller on EXYNOS chipset.
 	  If unsure, say N.
+
+config UFSHPB
+        tristate "Support UFS Host Performance Booster"
+        depends on SCSI_UFSHCD
+	help
+          A UFS HPB Feature improves random read performance. It caches
+          L2P map of UFS to host DRAM. The driver uses HPB read command
+          by piggybacking physical page number for bypassing FTL's L2P address
+          translation.
diff --git a/drivers/scsi/ufs/Makefile b/drivers/scsi/ufs/Makefile
index 433b871badfa..aa901b92e9e7 100644
--- a/drivers/scsi/ufs/Makefile
+++ b/drivers/scsi/ufs/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_SCSI_UFS_EXYNOS) += ufs-exynos.o
 obj-$(CONFIG_SCSI_UFSHCD) += ufshcd-core.o
 ufshcd-core-y				+= ufshcd.o ufs-sysfs.o ufsfeature.o
 ufshcd-core-$(CONFIG_SCSI_UFS_BSG)	+= ufs_bsg.o
+obj-$(CONFIG_UFSHPB) += ufshpb.o
 obj-$(CONFIG_SCSI_UFSHCD_PCI) += ufshcd-pci.o
 obj-$(CONFIG_SCSI_UFSHCD_PLATFORM) += ufshcd-pltfrm.o
 obj-$(CONFIG_SCSI_UFS_HISI) += ufs-hisi.o
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 082dfca8e237..2218f19fa9f4 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -2863,6 +2863,7 @@ int ufshcd_query_flag(struct ufs_hba *hba, enum query_opcode opcode,
 	ufshcd_release(hba);
 	return err;
 }
+EXPORT_SYMBOL(ufshcd_query_flag);
 
 /**
  * ufshcd_query_attr - API function for sending attribute requests
@@ -3061,6 +3062,7 @@ int ufshcd_query_descriptor_retry(struct ufs_hba *hba,
 
 	return err;
 }
+EXPORT_SYMBOL(ufshcd_query_descriptor_retry);
 
 /**
  * ufshcd_map_desc_id_to_length - map descriptor IDN to its length
diff --git a/drivers/scsi/ufs/ufshpb.c b/drivers/scsi/ufs/ufshpb.c
new file mode 100644
index 000000000000..84a9af2fdc80
--- /dev/null
+++ b/drivers/scsi/ufs/ufshpb.c
@@ -0,0 +1,777 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Universal Flash Storage Host Performance Booster
+ *
+ * Copyright (C) 2017-2018 Samsung Electronics Co., Ltd.
+ *
+ * Authors:
+ *	Yongmyung Lee <ymhungry.lee@samsung.com>
+ *	Jinyoung Choi <j-young.choi@samsung.com>
+ */
+
+#include <asm/unaligned.h>
+
+#include "ufshcd.h"
+#include "ufshpb.h"
+
+static struct ufshpb_driver ufshpb_drv;
+
+static int ufshpb_create_sysfs(struct ufs_hba *hba, struct ufshpb_lu *hpb);
+
+static inline int ufshpb_is_valid_srgn(struct ufshpb_region *rgn,
+			     struct ufshpb_subregion *srgn)
+{
+	return rgn->rgn_state != HPB_RGN_INACTIVE &&
+		srgn->srgn_state == HPB_SRGN_VALID;
+}
+
+static inline int ufshpb_get_state(struct ufshpb_lu *hpb)
+{
+	return atomic_read(&hpb->hpb_state);
+}
+
+static inline void ufshpb_set_state(struct ufshpb_lu *hpb, int state)
+{
+	atomic_set(&hpb->hpb_state, state);
+}
+
+static inline int ufshpb_lu_get_dev(struct ufshpb_lu *hpb)
+{
+	if (get_device(&hpb->hpb_lu_dev))
+		return 0;
+
+	return -ENODEV;
+}
+
+static inline int ufshpb_lu_get(struct ufshpb_lu *hpb)
+{
+	if (!hpb || (ufshpb_get_state(hpb) != HPB_PRESENT))
+		return -ENODEV;
+
+	if (ufshpb_lu_get_dev(hpb))
+		return -ENODEV;
+
+	return 0;
+}
+
+static inline void ufshpb_lu_put(struct ufshpb_lu *hpb)
+{
+	put_device(&hpb->hpb_lu_dev);
+}
+
+static void ufshpb_init_subregion_tbl(struct ufshpb_lu *hpb,
+				      struct ufshpb_region *rgn)
+{
+	int srgn_idx;
+
+	for (srgn_idx = 0; srgn_idx < rgn->srgn_cnt; srgn_idx++) {
+		struct ufshpb_subregion *srgn = rgn->srgn_tbl + srgn_idx;
+
+		srgn->rgn_idx = rgn->rgn_idx;
+		srgn->srgn_idx = srgn_idx;
+		srgn->srgn_state = HPB_SRGN_UNUSED;
+	}
+}
+
+static inline int ufshpb_alloc_subregion_tbl(struct ufshpb_lu *hpb,
+					     struct ufshpb_region *rgn,
+					     int srgn_cnt)
+{
+	rgn->srgn_tbl = kvcalloc(srgn_cnt, sizeof(struct ufshpb_subregion),
+				 GFP_KERNEL);
+	if (!rgn->srgn_tbl)
+		return -ENOMEM;
+
+	rgn->srgn_cnt = srgn_cnt;
+	return 0;
+}
+
+static void ufshpb_init_lu_parameter(struct ufs_hba *hba,
+				     struct ufshpb_lu *hpb,
+				     struct ufshpb_dev_info *hpb_dev_info,
+				     struct ufshpb_lu_info *hpb_lu_info)
+{
+	u32 entries_per_rgn;
+	u64 rgn_mem_size;
+
+
+	hpb->lu_pinned_start = hpb_lu_info->pinned_start;
+	hpb->lu_pinned_end = hpb_lu_info->num_pinned ?
+		(hpb_lu_info->pinned_start + hpb_lu_info->num_pinned - 1)
+		: PINNED_NOT_SET;
+
+	rgn_mem_size = (1ULL << hpb_dev_info->rgn_size) * HPB_RGN_SIZE_UNIT
+		/ HPB_ENTRY_BLOCK_SIZE * HPB_ENTRY_SIZE;
+	hpb->srgn_mem_size = (1ULL << hpb_dev_info->srgn_size)
+		* HPB_RGN_SIZE_UNIT / HPB_ENTRY_BLOCK_SIZE * HPB_ENTRY_SIZE;
+
+	entries_per_rgn = rgn_mem_size / HPB_ENTRY_SIZE;
+	hpb->entries_per_rgn_shift = ilog2(entries_per_rgn);
+	hpb->entries_per_rgn_mask = entries_per_rgn - 1;
+
+	hpb->entries_per_srgn = hpb->srgn_mem_size /  HPB_ENTRY_SIZE;
+	hpb->entries_per_srgn_shift = ilog2(hpb->entries_per_srgn);
+	hpb->entries_per_srgn_mask = hpb->entries_per_srgn - 1;
+
+	hpb->srgns_per_rgn = rgn_mem_size / hpb->srgn_mem_size;
+
+	hpb->rgns_per_lu = DIV_ROUND_UP(hpb_lu_info->num_blocks,
+				(rgn_mem_size / HPB_ENTRY_SIZE));
+	hpb->srgns_per_lu = DIV_ROUND_UP(hpb_lu_info->num_blocks,
+				(hpb->srgn_mem_size / HPB_ENTRY_SIZE));
+
+	hpb->pages_per_srgn = hpb->srgn_mem_size / PAGE_SIZE;
+
+	dev_info(hba->dev, "ufshpb(%d): region memory size - %llu (bytes)\n",
+		 hpb->lun, rgn_mem_size);
+	dev_info(hba->dev, "ufshpb(%d): subregion memory size - %u (bytes)\n",
+		 hpb->lun, hpb->srgn_mem_size);
+	dev_info(hba->dev, "ufshpb(%d): total blocks per lu - %d\n",
+		 hpb->lun, hpb_lu_info->num_blocks);
+	dev_info(hba->dev, "ufshpb(%d): subregions per region - %d, regions per lu - %u",
+		 hpb->lun, hpb->srgns_per_rgn, hpb->rgns_per_lu);
+}
+
+
+static int ufshpb_alloc_region_tbl(struct ufs_hba *hba, struct ufshpb_lu *hpb)
+{
+	struct ufshpb_region *rgn_table, *rgn;
+	int rgn_idx, i;
+	int ret = 0;
+
+	rgn_table = kvcalloc(hpb->rgns_per_lu, sizeof(struct ufshpb_region),
+			    GFP_KERNEL);
+	if (!rgn_table)
+		return -ENOMEM;
+
+	hpb->rgn_tbl = rgn_table;
+
+	for (rgn_idx = 0; rgn_idx < hpb->rgns_per_lu; rgn_idx++) {
+		int srgn_cnt = hpb->srgns_per_rgn;
+
+		rgn = rgn_table + rgn_idx;
+		rgn->rgn_idx = rgn_idx;
+
+		if (rgn_idx == hpb->rgns_per_lu - 1)
+			srgn_cnt = ((hpb->srgns_per_lu - 1) %
+				    hpb->srgns_per_rgn) + 1;
+
+		ret = ufshpb_alloc_subregion_tbl(hpb, rgn, srgn_cnt);
+		if (ret)
+			goto release_srgn_table;
+		ufshpb_init_subregion_tbl(hpb, rgn);
+
+		rgn->rgn_state = HPB_RGN_INACTIVE;
+	}
+
+	return 0;
+
+release_srgn_table:
+	for (i = 0; i < rgn_idx; i++) {
+		rgn = rgn_table + i;
+		if (rgn->srgn_tbl)
+			kvfree(rgn->srgn_tbl);
+	}
+	kvfree(rgn_table);
+	return ret;
+}
+
+static void ufshpb_destroy_subregion_tbl(struct ufshpb_lu *hpb,
+					 struct ufshpb_region *rgn)
+{
+	int srgn_idx;
+
+	for (srgn_idx = 0; srgn_idx < rgn->srgn_cnt; srgn_idx++) {
+		struct ufshpb_subregion *srgn;
+
+		srgn = rgn->srgn_tbl + srgn_idx;
+		srgn->srgn_state = HPB_SRGN_UNUSED;
+	}
+}
+
+static void ufshpb_destroy_region_tbl(struct ufshpb_lu *hpb)
+{
+	int rgn_idx;
+
+	for (rgn_idx = 0; rgn_idx < hpb->rgns_per_lu; rgn_idx++) {
+		struct ufshpb_region *rgn;
+
+		rgn = hpb->rgn_tbl + rgn_idx;
+		if (rgn->rgn_state != HPB_RGN_INACTIVE) {
+			rgn->rgn_state = HPB_RGN_INACTIVE;
+
+			ufshpb_destroy_subregion_tbl(hpb, rgn);
+		}
+
+		kvfree(rgn->srgn_tbl);
+	}
+
+	kvfree(hpb->rgn_tbl);
+}
+
+static int ufshpb_lu_hpb_init(struct ufs_hba *hba, struct ufshpb_lu *hpb,
+			      struct ufshpb_dev_info *hpb_dev_info)
+{
+	int ret;
+
+	spin_lock_init(&hpb->hpb_state_lock);
+
+	ret = ufshpb_alloc_region_tbl(hba, hpb);
+
+	ret = ufshpb_create_sysfs(hba, hpb);
+	if (ret)
+		goto release_rgn_table;
+
+	return 0;
+
+release_rgn_table:
+	ufshpb_destroy_region_tbl(hpb);
+	return ret;
+}
+
+static struct ufshpb_lu *ufshpb_alloc_hpb_lu(struct ufs_hba *hba, int lun,
+				     struct ufshpb_dev_info *hpb_dev_info,
+				     struct ufshpb_lu_info *hpb_lu_info)
+{
+	struct ufshpb_lu *hpb;
+	int ret;
+
+	hpb = kzalloc(sizeof(struct ufshpb_lu), GFP_KERNEL);
+	if (!hpb)
+		return NULL;
+
+	hpb->ufsf = &hba->ufsf;
+	hpb->lun = lun;
+
+	ufshpb_init_lu_parameter(hba, hpb, hpb_dev_info, hpb_lu_info);
+
+	ret = ufshpb_lu_hpb_init(hba, hpb, hpb_dev_info);
+	if (ret) {
+		dev_err(hba->dev, "hpb lu init failed. ret %d", ret);
+		goto release_hpb;
+	}
+
+	return hpb;
+release_hpb:
+	kfree(hpb);
+	return NULL;
+}
+
+static void ufshpb_lu_release(struct ufshpb_lu *hpb)
+{
+	ufshpb_destroy_region_tbl(hpb);
+
+	list_del_init(&hpb->list_hpb_lu);
+}
+
+static void ufshpb_issue_hpb_reset_query(struct ufs_hba *hba)
+{
+	int err;
+	int retries;
+
+	for (retries = 0; retries < HPB_RESET_REQ_RETRIES; retries++) {
+		err = ufshcd_query_flag(hba, UPIU_QUERY_OPCODE_SET_FLAG,
+				QUERY_FLAG_IDN_HPB_RESET, 0, NULL);
+		if (err)
+			dev_dbg(hba->dev,
+				"%s: failed with error %d, retries %d\n",
+				__func__, err, retries);
+		else
+			break;
+	}
+
+	if (err) {
+		dev_err(hba->dev,
+			"%s setting fHpbReset flag failed with error %d\n",
+			__func__, err);
+		return;
+	}
+}
+
+static void ufshpb_check_hpb_reset_query(struct ufs_hba *hba)
+{
+	int err;
+	bool flag_res = true;
+	int try = 0;
+
+	/* wait for the device to complete HPB reset query */
+	do {
+		if (++try == HPB_RESET_REQ_RETRIES)
+			break;
+
+		dev_info(hba->dev,
+			"%s start flag reset polling %d times\n",
+			__func__, try);
+
+		/* Poll fHpbReset flag to be cleared */
+		err = ufshcd_query_flag(hba, UPIU_QUERY_OPCODE_READ_FLAG,
+				QUERY_FLAG_IDN_HPB_RESET, 0, &flag_res);
+		usleep_range(1000, 1100);
+	} while (flag_res);
+
+	if (err) {
+		dev_err(hba->dev,
+			"%s reading fHpbReset flag failed with error %d\n",
+			__func__, err);
+		return;
+	}
+
+	if (flag_res) {
+		dev_err(hba->dev,
+			"%s fHpbReset was not cleared by the device\n",
+			__func__);
+	}
+}
+
+static void ufshpb_reset(struct ufs_hba *hba)
+{
+	struct ufshpb_lu *hpb;
+
+	list_for_each_entry(hpb, &ufshpb_drv.lh_hpb_lu, list_hpb_lu) {
+		if (ufshpb_lu_get_dev(hpb))
+			continue;
+
+		ufshpb_set_state(hpb, HPB_PRESENT);
+		ufshpb_lu_put(hpb);
+	}
+}
+
+static void ufshpb_reset_host(struct ufs_hba *hba)
+{
+	struct ufshpb_lu *hpb;
+
+	list_for_each_entry(hpb, &ufshpb_drv.lh_hpb_lu, list_hpb_lu) {
+		if (ufshpb_lu_get(hpb))
+			continue;
+
+		dev_info(&hpb->hpb_lu_dev, "ufshpb run reset_host");
+
+		ufshpb_set_state(hpb, HPB_RESET);
+		ufshpb_lu_put(hpb);
+	}
+}
+
+static void ufshpb_suspend(struct ufs_hba *hba)
+{
+	struct ufshpb_lu *hpb;
+
+	list_for_each_entry(hpb, &ufshpb_drv.lh_hpb_lu, list_hpb_lu) {
+		if (ufshpb_lu_get(hpb))
+			continue;
+
+		dev_info(&hpb->hpb_lu_dev, "ufshpb goto suspend");
+		ufshpb_set_state(hpb, HPB_SUSPEND);
+
+		ufshpb_lu_put(hpb);
+	}
+}
+
+static void ufshpb_resume(struct ufs_hba *hba)
+{
+	struct ufshpb_lu *hpb;
+
+	list_for_each_entry(hpb, &ufshpb_drv.lh_hpb_lu, list_hpb_lu) {
+		if (ufshpb_lu_get_dev(hpb))
+			continue;
+
+		dev_info(&hpb->hpb_lu_dev, "ufshpb resume");
+		ufshpb_set_state(hpb, HPB_PRESENT);
+		ufshpb_lu_put(hpb);
+	}
+}
+
+static void ufshpb_stat_init(struct ufshpb_lu *hpb)
+{
+	atomic_set(&hpb->stats.hit_cnt, 0);
+	atomic_set(&hpb->stats.miss_cnt, 0);
+	atomic_set(&hpb->stats.rb_noti_cnt, 0);
+	atomic_set(&hpb->stats.rb_active_cnt, 0);
+	atomic_set(&hpb->stats.rb_inactive_cnt, 0);
+	atomic_set(&hpb->stats.map_req_cnt, 0);
+}
+
+/* SYSFS functions */
+#define ufshpb_sysfs_attr_show_func(__name)				\
+static ssize_t __name##_show(struct device *dev,		\
+					 struct device_attribute *attr,	\
+					 char *buf)			\
+{									\
+	struct ufshpb_lu *hpb;						\
+	hpb = container_of(dev, struct ufshpb_lu, hpb_lu_dev);		\
+	return snprintf(buf, PAGE_SIZE, "%d\n",			\
+			atomic_read(&hpb->stats.__name));		\
+}
+
+ufshpb_sysfs_attr_show_func(hit_cnt);
+ufshpb_sysfs_attr_show_func(miss_cnt);
+ufshpb_sysfs_attr_show_func(rb_noti_cnt);
+ufshpb_sysfs_attr_show_func(rb_active_cnt);
+ufshpb_sysfs_attr_show_func(rb_inactive_cnt);
+ufshpb_sysfs_attr_show_func(map_req_cnt);
+
+static DEVICE_ATTR_RO(hit_cnt);
+static DEVICE_ATTR_RO(miss_cnt);
+static DEVICE_ATTR_RO(rb_noti_cnt);
+static DEVICE_ATTR_RO(rb_active_cnt);
+static DEVICE_ATTR_RO(rb_inactive_cnt);
+static DEVICE_ATTR_RO(map_req_cnt);
+
+static struct attribute *hpb_dev_attrs[] = {
+	&dev_attr_hit_cnt.attr,
+	&dev_attr_miss_cnt.attr,
+	&dev_attr_rb_noti_cnt.attr,
+	&dev_attr_rb_active_cnt.attr,
+	&dev_attr_rb_inactive_cnt.attr,
+	&dev_attr_map_req_cnt.attr,
+	NULL,
+};
+
+static struct attribute_group ufshpb_sysfs_group = {
+	.attrs = hpb_dev_attrs,
+};
+
+static inline void ufshpb_dev_release(struct device *dev)
+{
+	struct ufs_hba *hba;
+	struct ufsf_feature_info *ufsf;
+	struct ufshpb_lu *hpb;
+
+	hpb = container_of(dev, struct ufshpb_lu, hpb_lu_dev);
+	ufsf = hpb->ufsf;
+	hba = container_of(ufsf, struct ufs_hba, ufsf);
+
+	ufshpb_lu_release(hpb);
+	dev_info(dev, "%s: release success\n", __func__);
+	put_device(dev->parent);
+
+	kfree(hpb);
+}
+
+static int ufshpb_create_sysfs(struct ufs_hba *hba, struct ufshpb_lu *hpb)
+{
+	int ret;
+
+	device_initialize(&hpb->hpb_lu_dev);
+
+	ufshpb_stat_init(hpb);
+
+	hpb->hpb_lu_dev.parent = get_device(&hba->ufsf.hpb_dev);
+	hpb->hpb_lu_dev.release = ufshpb_dev_release;
+	dev_set_name(&hpb->hpb_lu_dev, "ufshpb_lu%d", hpb->lun);
+
+	ret = device_add(&hpb->hpb_lu_dev);
+	if (ret) {
+		dev_err(hba->dev, "ufshpb(%d) device_add failed",
+			hpb->lun);
+		return -ENODEV;
+	}
+
+	if (device_add_group(&hpb->hpb_lu_dev, &ufshpb_sysfs_group))
+		dev_err(hba->dev, "ufshpb(%d) create file error\n",
+			hpb->lun);
+
+	return 0;
+}
+
+static int ufshpb_read_desc(struct ufs_hba *hba, u8 desc_id, u8 desc_index,
+			  u8 selector, u8 *desc_buf)
+{
+	int err = 0;
+	int size;
+
+	ufshcd_map_desc_id_to_length(hba, desc_id, &size);
+
+	pm_runtime_get_sync(hba->dev);
+
+	err = ufshcd_query_descriptor_retry(hba, UPIU_QUERY_OPCODE_READ_DESC,
+					    desc_id, desc_index,
+					    selector,
+					    desc_buf, &size);
+	if (err)
+		dev_err(hba->dev, "read desc failed: %d, id %d, idx %d\n",
+			err, desc_id, desc_index);
+
+	pm_runtime_put_sync(hba->dev);
+
+	return err;
+}
+
+static int ufshpb_get_geo_info(struct ufs_hba *hba, u8 *geo_buf,
+			       struct ufshpb_dev_info *hpb_dev_info)
+{
+	int hpb_device_max_active_rgns = 0;
+	int hpb_num_lu;
+
+	hpb_num_lu = geo_buf[GEOMETRY_DESC_HPB_NUMBER_LU];
+	if (hpb_num_lu == 0) {
+		dev_err(hba->dev, "No HPB LU supported\n");
+		return -ENODEV;
+	}
+
+	hpb_dev_info->rgn_size = geo_buf[GEOMETRY_DESC_HPB_REGION_SIZE];
+	hpb_dev_info->srgn_size = geo_buf[GEOMETRY_DESC_HPB_SUBREGION_SIZE];
+	hpb_device_max_active_rgns =
+		get_unaligned_be16(geo_buf +
+			GEOMETRY_DESC_HPB_DEVICE_MAX_ACTIVE_REGIONS);
+
+	if (hpb_dev_info->rgn_size == 0 || hpb_dev_info->srgn_size == 0 ||
+	    hpb_device_max_active_rgns == 0) {
+		dev_err(hba->dev, "No HPB supported device\n");
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static int ufshpb_get_dev_info(struct ufs_hba *hba,
+			       struct ufshpb_dev_info *hpb_dev_info,
+			       u8 *desc_buf)
+{
+	int ret;
+	int hpb_mode, version;
+
+	ret = ufshpb_read_desc(hba, QUERY_DESC_IDN_DEVICE, 0, 0, desc_buf);
+	if (ret) {
+		dev_err(hba->dev, "%s: idn: %d query request failed\n",
+			__func__, QUERY_DESC_IDN_DEVICE);
+		return -ENODEV;
+	}
+
+	hpb_mode = get_unaligned_be16(desc_buf + DEVICE_DESC_PARAM_HPB_CONTROL);
+	if (hpb_mode == HPB_HOST_CONTROL) {
+		dev_err(hba->dev, "%s: host control mode is not supported.\n",
+			__func__);
+		return -ENODEV;
+	}
+
+	version = get_unaligned_be16(desc_buf + DEVICE_DESC_PARAM_HPB_VER);
+	if (version != HPB_SUPPORT_VERSION) {
+		dev_err(hba->dev, "%s: HPB %x version is not supported.\n",
+			__func__, version);
+		return -ENODEV;
+	}
+
+	/*
+	 * Get the number of user logical unit to check whether all
+	 * scsi_device finish initialization
+	 */
+	hpb_dev_info->num_lu = desc_buf[DEVICE_DESC_PARAM_NUM_LU];
+
+	ret = ufshpb_read_desc(hba, QUERY_DESC_IDN_GEOMETRY, 0, 0, desc_buf);
+	if (ret) {
+		dev_err(hba->dev, "%s: idn: %d query request failed\n",
+			__func__, QUERY_DESC_IDN_DEVICE);
+		return ret;
+	}
+
+	ret = ufshpb_get_geo_info(hba, desc_buf, hpb_dev_info);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int ufshpb_get_lu_info(struct ufs_hba *hba, int lun,
+				    struct ufshpb_lu_info *hpb_lu_info,
+				    u8 *desc_buf)
+{
+	u16 max_active_rgns;
+	u8 lu_enable;
+	int ret;
+
+	ret = ufshpb_read_desc(hba, QUERY_DESC_IDN_UNIT, lun, 0, desc_buf);
+	if (ret) {
+		dev_err(hba->dev,
+			"%s: idn: %d lun: %d  query request failed",
+			__func__, QUERY_DESC_IDN_UNIT, lun);
+		return ret;
+	}
+
+	lu_enable = desc_buf[UNIT_DESC_PARAM_LU_ENABLE];
+	if (lu_enable != LU_ENABLED_HPB_FUNC)
+		return -ENODEV;
+
+	max_active_rgns = get_unaligned_be16(
+			desc_buf + UNIT_DESC_HPB_LU_MAX_ACTIVE_REGIONS);
+	if (!max_active_rgns) {
+		dev_err(hba->dev,
+			"lun %d wrong number of max active regions\n", lun);
+		return -ENODEV;
+	}
+
+	hpb_lu_info->num_blocks = get_unaligned_be64(
+			desc_buf + UNIT_DESC_PARAM_LOGICAL_BLK_COUNT);
+	hpb_lu_info->pinned_start = get_unaligned_be16(
+			desc_buf + UNIT_DESC_HPB_LU_PIN_REGION_START_OFFSET);
+	hpb_lu_info->num_pinned = get_unaligned_be16(
+			desc_buf + UNIT_DESC_HPB_LU_NUM_PIN_REGIONS);
+	hpb_lu_info->max_active_rgns = max_active_rgns;
+
+	return 0;
+}
+
+static void ufshpb_scan_hpb_lu(struct ufs_hba *hba,
+			       struct ufshpb_dev_info *hpb_dev_info,
+			       u8 *desc_buf)
+{
+	struct scsi_device *sdev;
+	struct ufshpb_lu *hpb;
+	int find_hpb_lu = 0;
+	int ret;
+
+	INIT_LIST_HEAD(&ufshpb_drv.lh_hpb_lu);
+
+	shost_for_each_device(sdev, hba->host) {
+		struct ufshpb_lu_info hpb_lu_info = { 0 };
+		int lun = sdev->lun;
+
+		if (lun >= hba->dev_info.max_lu_supported)
+			continue;
+
+		ret = ufshpb_get_lu_info(hba, lun, &hpb_lu_info, desc_buf);
+		if (ret)
+			continue;
+
+		hpb = ufshpb_alloc_hpb_lu(hba, lun, hpb_dev_info,
+					  &hpb_lu_info);
+		if (!hpb)
+			continue;
+
+		hpb->sdev_ufs_lu = sdev;
+		sdev->hostdata = hpb;
+
+		list_add_tail(&hpb->list_hpb_lu, &ufshpb_drv.lh_hpb_lu);
+		find_hpb_lu++;
+	}
+
+	if (!find_hpb_lu)
+		return;
+
+	ufshpb_check_hpb_reset_query(hba);
+	dev_set_drvdata(&hba->ufsf.hpb_dev, &ufshpb_drv);
+
+	list_for_each_entry(hpb, &ufshpb_drv.lh_hpb_lu, list_hpb_lu) {
+		dev_info(&hpb->hpb_lu_dev, "set state to present\n");
+		ufshpb_set_state(hpb, HPB_PRESENT);
+	}
+}
+
+static int ufshpb_probe(struct device *dev)
+{
+	struct ufs_hba *hba;
+	struct ufsf_feature_info *ufsf;
+	struct ufshpb_dev_info hpb_dev_info = { 0 };
+	char *desc_buf;
+	int ret;
+
+	if (dev->type != &ufshpb_dev_type)
+		return -ENODEV;
+
+	ufsf = container_of(dev, struct ufsf_feature_info, hpb_dev);
+	hba = container_of(ufsf, struct ufs_hba, ufsf);
+
+	desc_buf = kzalloc(QUERY_DESC_MAX_SIZE, GFP_KERNEL);
+	if (!desc_buf)
+		goto release_desc_buf;
+
+	ret = ufshpb_get_dev_info(hba, &hpb_dev_info, desc_buf);
+	if (ret)
+		goto release_desc_buf;
+
+	/*
+	 * Because HPB driver uses scsi_device data structure,
+	 * we should wait at this point until finishing initialization of all
+	 * scsi devices. Even if timeout occurs, HPB driver will search
+	 * the scsi_device list on struct scsi_host (shost->__host list_head)
+	 * and can find out HPB logical units in all scsi_devices
+	 */
+	wait_event_timeout(hba->ufsf.sdev_wait,
+			   (atomic_read(&hba->ufsf.slave_conf_cnt)
+				== hpb_dev_info.num_lu),
+			   SDEV_WAIT_TIMEOUT);
+
+	ufshpb_issue_hpb_reset_query(hba);
+
+	dev_dbg(hba->dev, "ufshpb: slave count %d, lu count %d\n",
+		atomic_read(&hba->ufsf.slave_conf_cnt), hpb_dev_info.num_lu);
+
+	ufshpb_scan_hpb_lu(hba, &hpb_dev_info, desc_buf);
+
+release_desc_buf:
+	kfree(desc_buf);
+	return 0;
+}
+
+static int ufshpb_remove(struct device *dev)
+{
+	struct ufshpb_lu *hpb, *n_hpb;
+	struct ufsf_feature_info *ufsf;
+	struct scsi_device *sdev;
+
+	ufsf = container_of(dev, struct ufsf_feature_info, hpb_dev);
+
+	dev_set_drvdata(&ufsf->hpb_dev, NULL);
+
+	list_for_each_entry_safe(hpb, n_hpb, &ufshpb_drv.lh_hpb_lu,
+				 list_hpb_lu) {
+		ufshpb_set_state(hpb, HPB_FAILED);
+
+		sdev = hpb->sdev_ufs_lu;
+		sdev->hostdata = NULL;
+
+		device_del(&hpb->hpb_lu_dev);
+
+		dev_info(&hpb->hpb_lu_dev, "hpb_lu_dev refcnt %d\n",
+			 kref_read(&hpb->hpb_lu_dev.kobj.kref));
+		put_device(&hpb->hpb_lu_dev);
+	}
+	dev_info(dev, "ufshpb: remove success\n");
+
+	return 0;
+}
+
+static struct ufshpb_driver ufshpb_drv = {
+	.drv = {
+		.name = "ufshpb_driver",
+		.owner = THIS_MODULE,
+		.probe = ufshpb_probe,
+		.remove = ufshpb_remove,
+		.bus = &ufsf_bus_type,
+		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
+	},
+	.ufshpb_ops = {
+		.reset = ufshpb_reset,
+		.reset_host = ufshpb_reset_host,
+		.suspend = ufshpb_suspend,
+		.resume = ufshpb_resume,
+	},
+};
+
+unsigned int ufshpb_host_map_kbytes = 1 * 1024;
+module_param(ufshpb_host_map_kbytes, uint, 0644);
+MODULE_PARM_DESC(ufshpb_host_map_kbytes,
+	 "ufshpb host mapping memory kilo-bytes for ufshpb memory-pool");
+
+static int __init ufshpb_init(void)
+{
+	int ret;
+
+	ret = driver_register(&ufshpb_drv.drv);
+	if (ret)
+		pr_err("ufshpb: driver register failed\n");
+
+	return ret;
+}
+
+static void __exit ufshpb_exit(void)
+{
+	driver_unregister(&ufshpb_drv.drv);
+}
+
+MODULE_AUTHOR("Yongmyong Lee <ymhungry.lee@samsung.com>");
+MODULE_AUTHOR("Jinyoung Choi <j-young.choi@samsung.com>");
+MODULE_DESCRIPTION("UFS Host Performance Booster Driver");
+
+module_init(ufshpb_init);
+module_exit(ufshpb_exit);
+MODULE_LICENSE("GPL");
diff --git a/drivers/scsi/ufs/ufshpb.h b/drivers/scsi/ufs/ufshpb.h
new file mode 100644
index 000000000000..eaa4a3e035b1
--- /dev/null
+++ b/drivers/scsi/ufs/ufshpb.h
@@ -0,0 +1,162 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Universal Flash Storage Host Performance Booster
+ *
+ * Copyright (C) 2017-2018 Samsung Electronics Co., Ltd.
+ *
+ * Authors:
+ *	Yongmyung Lee <ymhungry.lee@samsung.com>
+ *	Jinyoung Choi <j-young.choi@samsung.com>
+ */
+
+#ifndef _UFSHPB_H_
+#define _UFSHPB_H_
+
+/* hpb response UPIU macro */
+#define MAX_ACTIVE_NUM				2
+#define MAX_INACTIVE_NUM			2
+#define HPB_RSP_NONE				0x00
+#define HPB_RSP_REQ_REGION_UPDATE		0x01
+#define HPB_RSP_DEV_RESET			0x02
+#define DEV_DATA_SEG_LEN			0x14
+#define DEV_SENSE_SEG_LEN			0x12
+#define DEV_DES_TYPE				0x80
+#define DEV_ADDITIONAL_LEN			0x10
+
+/* hpb map & entries macro */
+#define HPB_RGN_SIZE_UNIT			512
+#define HPB_ENTRY_BLOCK_SIZE			4096
+#define HPB_ENTRY_SIZE				0x8
+#define PINNED_NOT_SET				U32_MAX
+
+/* hpb support chunk size */
+#define HPB_MULTI_CHUNK_HIGH			1
+
+/* hpb vender defined opcode */
+#define UFSHPB_READ				0xF8
+#define UFSHPB_READ_BUFFER			0xF9
+#define UFSHPB_WRITE_BUFFER			0xFA
+#define UFSHPB_READ_BUFFER_ID			0x01
+#define UFSHPB_WRITE_BUFFER_ID			0x02
+#define HPB_READ_BUFFER_CMD_LENGTH		10
+#define LU_ENABLED_HPB_FUNC			0x02
+
+#define SDEV_WAIT_TIMEOUT			(10 * HZ)
+#define MAP_REQ_TIMEOUT				(30 * HZ)
+#define HPB_RESET_REQ_RETRIES			10
+#define HPB_RESET_REQ_MSLEEP			2
+
+#define HPB_SUPPORT_VERSION			0x100
+
+enum UFSHPB_MODE {
+	HPB_HOST_CONTROL,
+	HPB_DEVICE_CONTROL,
+};
+
+enum UFSHPB_STATE {
+	HPB_PRESENT = 1,
+	HPB_SUSPEND,
+	HPB_FAILED,
+	HPB_RESET,
+};
+
+enum HPB_RGN_STATE {
+	HPB_RGN_INACTIVE,
+	HPB_RGN_ACTIVE,
+	/* pinned regions are always active */
+	HPB_RGN_PINNED,
+};
+
+enum HPB_SRGN_STATE {
+	HPB_SRGN_UNUSED,
+	HPB_SRGN_INVALID,
+	HPB_SRGN_VALID,
+	HPB_SRGN_ISSUED,
+};
+
+/**
+ * struct ufshpb_dev_info - UFSHPB device related info
+ * @num_lu: the number of user logical unit to check whether all lu finished
+ *          initialization
+ * @rgn_size: device reported HPB region size
+ * @srgn_size: device reported HPB sub-region size
+ */
+struct ufshpb_dev_info {
+	int num_lu;
+	int rgn_size;
+	int srgn_size;
+};
+
+/**
+ * struct ufshpb_lu_info - UFSHPB logical unit related info
+ * @num_blocks: the number of logical block
+ * @pinned_start: the start region number of pinned region
+ * @num_pinned: the number of pinned regions
+ * @max_active_rgns: maximum number of active regions
+ */
+struct ufshpb_lu_info {
+	int num_blocks;
+	int pinned_start;
+	int num_pinned;
+	int max_active_rgns;
+};
+
+struct ufshpb_subregion {
+	enum HPB_SRGN_STATE srgn_state;
+	int rgn_idx;
+	int srgn_idx;
+};
+
+struct ufshpb_region {
+	struct ufshpb_subregion *srgn_tbl;
+	enum HPB_RGN_STATE rgn_state;
+	int rgn_idx;
+	int srgn_cnt;
+};
+
+struct ufshpb_stats {
+	atomic_t hit_cnt;
+	atomic_t miss_cnt;
+	atomic_t rb_noti_cnt;
+	atomic_t rb_active_cnt;
+	atomic_t rb_inactive_cnt;
+	atomic_t map_req_cnt;
+};
+
+struct ufshpb_lu {
+	int lun;
+
+	struct device hpb_lu_dev;
+	struct scsi_device *sdev_ufs_lu;
+
+	struct ufshpb_region *rgn_tbl;
+
+	spinlock_t hpb_state_lock;
+	atomic_t hpb_state; /* hpb_state_lock */
+
+	/* pinned region information */
+	u32 lu_pinned_start;
+	u32 lu_pinned_end;
+
+	/* HPB related configuration */
+	u32 rgns_per_lu;
+	u32 srgns_per_lu;
+	int srgns_per_rgn;
+	u32 srgn_mem_size;
+	u32 entries_per_rgn_mask;
+	u32 entries_per_rgn_shift;
+	u32 entries_per_srgn;
+	u32 entries_per_srgn_mask;
+	u32 entries_per_srgn_shift;
+	u32 pages_per_srgn;
+
+	struct ufshpb_stats stats;
+
+	struct ufsf_feature_info *ufsf;
+	struct list_head list_hpb_lu;
+};
+
+extern struct device_type ufshpb_dev_type;
+extern struct bus_type ufsf_bus_type;
+
+#endif /* End of Header */
-- 
2.17.1

[RFC PATCH v3 4/5] scsi: ufs: L2P map management for HPB read

[Daejun Park]

This is a patch for managing L2P map in HPB module.

The HPB divides logical addresses into several regions. A region consists
of several sub-regions. The sub-region is a basic unit where L2P mapping is
managed. The driver loads L2P mapping data of each sub-region. The loaded
sub-region is called active-state. The HPB driver unloads L2P mapping data
as region unit. The unloaded region is called inactive-state.

Sub-region/region candidates to be loaded and unloaded are delivered from
the UFS device. The UFS device delivers the recommended active sub-region
and inactivate region to the driver using sensedata.
The HPB module performs L2P mapping management on the host through the
delivered information.

A pinned region is a pre-set regions on the UFS device that is always
activate-state.

The data structure for map data request and L2P map uses mempool API,
minimizing allocation overhead while avoiding static allocation.

The map_work manages active/inactive by 2 "to-do" lists.
Each hpb lun maintains 2 "to-do" lists:
  hpb->lh_inact_rgn - regions to be inactivated, and
  hpb->lh_act_srgn - subregions to be activated
Those lists are maintained on IO completion.

Signed-off-by: Daejun Park <daejun7.park@samsung.com>
---
 drivers/scsi/ufs/ufshpb.c | 992 +++++++++++++++++++++++++++++++++++++-
 drivers/scsi/ufs/ufshpb.h |  72 +++
 2 files changed, 1060 insertions(+), 4 deletions(-)

diff --git a/drivers/scsi/ufs/ufshpb.c b/drivers/scsi/ufs/ufshpb.c
index 84a9af2fdc80..e1af4c2ed9ab 100644
--- a/drivers/scsi/ufs/ufshpb.c
+++ b/drivers/scsi/ufs/ufshpb.c
@@ -15,6 +15,7 @@
 #include "ufshpb.h"
 
 static struct ufshpb_driver ufshpb_drv;
+unsigned int ufshpb_host_map_kbytes = 1 * 1024;
 
 static int ufshpb_create_sysfs(struct ufs_hba *hba, struct ufshpb_lu *hpb);
 
@@ -25,6 +26,63 @@ static inline int ufshpb_is_valid_srgn(struct ufshpb_region *rgn,
 		srgn->srgn_state == HPB_SRGN_VALID;
 }
 
+static inline bool ufshpb_is_general_lun(int lun)
+{
+	return lun < UFS_UPIU_MAX_UNIT_NUM_ID;
+}
+
+static inline bool
+ufshpb_is_pinned_region(struct ufshpb_lu *hpb, int rgn_idx)
+{
+	if (hpb->lu_pinned_end != PINNED_NOT_SET &&
+	    rgn_idx >= hpb->lu_pinned_start &&
+	    rgn_idx <= hpb->lu_pinned_end)
+		return true;
+
+	return false;
+}
+
+static bool ufshpb_is_empty_rsp_lists(struct ufshpb_lu *hpb)
+{
+	bool ret = true;
+	unsigned long flags;
+
+	spin_lock_irqsave(&hpb->rsp_list_lock, flags);
+	if (!list_empty(&hpb->lh_inact_rgn) || !list_empty(&hpb->lh_act_srgn))
+		ret = false;
+	spin_unlock_irqrestore(&hpb->rsp_list_lock, flags);
+
+	return ret;
+}
+
+static inline int ufshpb_may_field_valid(struct ufs_hba *hba,
+					 struct ufshcd_lrb *lrbp,
+					 struct ufshpb_rsp_field *rsp_field)
+{
+	if (be16_to_cpu(rsp_field->sense_data_len) != DEV_SENSE_SEG_LEN ||
+	    rsp_field->desc_type != DEV_DES_TYPE ||
+	    rsp_field->additional_len != DEV_ADDITIONAL_LEN ||
+	    rsp_field->hpb_type == HPB_RSP_NONE ||
+	    rsp_field->active_rgn_cnt > MAX_ACTIVE_NUM ||
+	    rsp_field->inactive_rgn_cnt > MAX_INACTIVE_NUM ||
+	    (!rsp_field->active_rgn_cnt && !rsp_field->inactive_rgn_cnt))
+		return -EINVAL;
+
+	if (!ufshpb_is_general_lun(lrbp->lun)) {
+		dev_warn(hba->dev, "ufshpb: lun(%d) not supported\n",
+			 lrbp->lun);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+
+static inline struct ufshpb_lu *ufshpb_get_hpb_data(struct scsi_cmnd *cmd)
+{
+	return cmd->device->hostdata;
+}
+
 static inline int ufshpb_get_state(struct ufshpb_lu *hpb)
 {
 	return atomic_read(&hpb->hpb_state);
@@ -59,6 +117,765 @@ static inline void ufshpb_lu_put(struct ufshpb_lu *hpb)
 	put_device(&hpb->hpb_lu_dev);
 }
 
+static struct ufshpb_req *ufshpb_get_map_req(struct ufshpb_lu *hpb,
+					     struct ufshpb_subregion *srgn)
+{
+	struct ufshpb_req *map_req;
+	struct request *req;
+	struct bio *bio;
+
+	map_req = kmem_cache_alloc(hpb->map_req_cache, GFP_KERNEL);
+	if (!map_req)
+		return NULL;
+
+	req = blk_get_request(hpb->sdev_ufs_lu->request_queue,
+			      REQ_OP_SCSI_IN, BLK_MQ_REQ_PREEMPT);
+	if (IS_ERR(req))
+		goto free_map_req;
+
+	bio = bio_alloc(GFP_KERNEL, hpb->pages_per_srgn);
+	if (!bio) {
+		blk_put_request(req);
+		goto free_map_req;
+	}
+
+	map_req->hpb = hpb;
+	map_req->req = req;
+	map_req->bio = bio;
+
+	map_req->rgn_idx = srgn->rgn_idx;
+	map_req->srgn_idx = srgn->srgn_idx;
+	map_req->mctx = srgn->mctx;
+	map_req->lun = hpb->lun;
+
+	return map_req;
+
+free_map_req:
+	kmem_cache_free(hpb->map_req_cache, map_req);
+	return NULL;
+}
+
+static inline void ufshpb_put_map_req(struct ufshpb_lu *hpb,
+				      struct ufshpb_req *map_req)
+{
+	bio_put(map_req->bio);
+	blk_put_request(map_req->req);
+	kmem_cache_free(hpb->map_req_cache, map_req);
+}
+
+
+static inline int ufshpb_clear_dirty_bitmap(struct ufshpb_lu *hpb,
+				     struct ufshpb_subregion *srgn)
+{
+	WARN_ON(!srgn->mctx);
+	bitmap_zero(srgn->mctx->ppn_dirty, hpb->entries_per_srgn);
+	return 0;
+}
+
+static void ufshpb_update_active_info(struct ufshpb_lu *hpb, int rgn_idx,
+				      int srgn_idx)
+{
+	struct ufshpb_region *rgn;
+	struct ufshpb_subregion *srgn;
+
+	rgn = hpb->rgn_tbl + rgn_idx;
+	srgn = rgn->srgn_tbl + srgn_idx;
+
+	list_del_init(&rgn->list_inact_rgn);
+
+	if (list_empty(&srgn->list_act_srgn))
+		list_add_tail(&srgn->list_act_srgn, &hpb->lh_act_srgn);
+}
+
+static void ufshpb_update_inactive_info(struct ufshpb_lu *hpb, int rgn_idx)
+{
+	struct ufshpb_region *rgn;
+	struct ufshpb_subregion *srgn;
+	int srgn_idx;
+
+	rgn = hpb->rgn_tbl + rgn_idx;
+
+	for (srgn_idx = 0; srgn_idx < rgn->srgn_cnt; srgn_idx++) {
+		srgn = rgn->srgn_tbl + srgn_idx;
+
+		list_del_init(&srgn->list_act_srgn);
+	}
+
+	if (list_empty(&rgn->list_inact_rgn))
+		list_add_tail(&rgn->list_inact_rgn, &hpb->lh_inact_rgn);
+}
+
+static void ufshpb_activate_subregion(struct ufshpb_lu *hpb,
+					  struct ufshpb_subregion *srgn)
+{
+	struct ufshpb_region *rgn;
+
+	/*
+	 * If there is no mctx in subregion
+	 * after I/O progress for HPB_READ_BUFFER, the region to which the
+	 * subregion belongs was evicted.
+	 * Mask sure the the region must not evict in I/O progress
+	 */
+	WARN_ON(!srgn->mctx);
+
+	rgn = hpb->rgn_tbl + srgn->rgn_idx;
+
+	if (unlikely(rgn->rgn_state == HPB_RGN_INACTIVE)) {
+		dev_err(&hpb->hpb_lu_dev,
+			"region %d subregion %d evicted\n",
+			srgn->rgn_idx, srgn->srgn_idx);
+		return;
+	}
+	srgn->srgn_state = HPB_SRGN_VALID;
+}
+
+static void ufshpb_map_req_compl_fn(struct request *req, blk_status_t error)
+{
+	struct ufshpb_req *map_req = (struct ufshpb_req *) req->end_io_data;
+	struct ufshpb_lu *hpb = map_req->hpb;
+	struct ufshpb_subregion *srgn;
+	unsigned long flags;
+
+	srgn = hpb->rgn_tbl[map_req->rgn_idx].srgn_tbl +
+		map_req->srgn_idx;
+
+	spin_lock_irqsave(&hpb->hpb_state_lock, flags);
+	ufshpb_activate_subregion(hpb, srgn);
+	spin_unlock_irqrestore(&hpb->hpb_state_lock, flags);
+
+	ufshpb_put_map_req(map_req->hpb, map_req);
+	ufshpb_lu_put(hpb);
+}
+
+static inline void ufshpb_set_read_buf_cmd(unsigned char *cdb, int rgn_idx,
+					   int srgn_idx, int srgn_mem_size)
+{
+	cdb[0] = UFSHPB_READ_BUFFER;
+	cdb[1] = UFSHPB_READ_BUFFER_ID;
+
+	put_unaligned_be16(rgn_idx, &cdb[2]);
+	put_unaligned_be16(srgn_idx, &cdb[4]);
+	put_unaligned_be24(srgn_mem_size, &cdb[6]);
+
+	cdb[9] = 0x00;
+}
+
+static int ufshpb_map_req_add_bio_page(struct ufshpb_lu *hpb,
+				       struct request_queue *q, struct bio *bio,
+				       struct ufshpb_map_ctx *mctx)
+{
+	int i, ret = 0;
+
+	for (i = 0; i < hpb->pages_per_srgn; i++) {
+		ret = bio_add_pc_page(q, bio, mctx->m_page[i], PAGE_SIZE, 0);
+		if (ret != PAGE_SIZE) {
+			dev_notice(&hpb->hpb_lu_dev,
+				   "bio_add_pc_page fail %d\n", ret);
+			return -ENOMEM;
+		}
+	}
+
+	return 0;
+}
+
+static int ufshpb_execute_map_req(struct ufshpb_lu *hpb,
+				  struct ufshpb_req *map_req)
+{
+	struct request_queue *q;
+	struct request *req;
+	struct scsi_request *rq;
+	int ret = 0;
+
+	q = hpb->sdev_ufs_lu->request_queue;
+	ret = ufshpb_map_req_add_bio_page(hpb, q, map_req->bio,
+					  map_req->mctx);
+	if (ret) {
+		dev_notice(&hpb->hpb_lu_dev,
+			   "map_req_add_bio_page fail %d - %d\n",
+			   map_req->rgn_idx, map_req->srgn_idx);
+		return ret;
+	}
+
+	req = map_req->req;
+
+	blk_rq_append_bio(req, &map_req->bio);
+
+	req->timeout = 0;
+	req->end_io_data = (void *)map_req;
+
+	rq = scsi_req(req);
+	ufshpb_set_read_buf_cmd(rq->cmd, map_req->rgn_idx,
+				map_req->srgn_idx, hpb->srgn_mem_size);
+	rq->cmd_len = HPB_READ_BUFFER_CMD_LENGTH;
+
+	blk_execute_rq_nowait(q, NULL, req, 1, ufshpb_map_req_compl_fn);
+
+	atomic_inc(&hpb->stats.map_req_cnt);
+	return 0;
+}
+
+static struct ufshpb_map_ctx *ufshpb_get_map_ctx(struct ufshpb_lu *hpb)
+{
+	struct ufshpb_map_ctx *mctx;
+	int i, j;
+
+	mctx = mempool_alloc(ufshpb_drv.ufshpb_mctx_pool, GFP_KERNEL);
+	if (!mctx)
+		return NULL;
+
+	mctx->m_page = kmem_cache_alloc(hpb->m_page_cache, GFP_KERNEL);
+	if (!mctx->m_page)
+		goto release_mctx;
+
+	mctx->ppn_dirty = bitmap_zalloc(hpb->entries_per_srgn, GFP_KERNEL);
+	if (!mctx->ppn_dirty)
+		goto release_m_page;
+
+	for (i = 0; i < hpb->pages_per_srgn; i++) {
+		mctx->m_page[i] = mempool_alloc(ufshpb_drv.ufshpb_page_pool,
+						GFP_KERNEL);
+		if (!mctx->m_page[i]) {
+			for (j = 0; j < i; j++)
+				mempool_free(mctx->m_page[j],
+					     ufshpb_drv.ufshpb_page_pool);
+			goto release_ppn_dirty;
+		}
+		clear_page(page_address(mctx->m_page[i]));
+	}
+
+	return mctx;
+release_ppn_dirty:
+	bitmap_free(mctx->ppn_dirty);
+release_m_page:
+	kmem_cache_free(hpb->m_page_cache, mctx->m_page);
+release_mctx:
+	mempool_free(mctx, ufshpb_drv.ufshpb_mctx_pool);
+	return NULL;
+}
+
+static inline void ufshpb_put_map_ctx(struct ufshpb_lu *hpb,
+				      struct ufshpb_map_ctx *mctx)
+{
+	int i;
+
+	for (i = 0; i < hpb->pages_per_srgn; i++)
+		mempool_free(mctx->m_page[i],
+			     ufshpb_drv.ufshpb_page_pool);
+
+	bitmap_free(mctx->ppn_dirty);
+	kmem_cache_free(hpb->m_page_cache, mctx->m_page);
+	mempool_free(mctx, ufshpb_drv.ufshpb_mctx_pool);
+}
+
+static int ufshpb_check_issue_state_srgns(struct ufshpb_lu *hpb,
+					  struct ufshpb_region *rgn)
+{
+	struct ufshpb_subregion *srgn;
+	int srgn_idx;
+
+	for (srgn_idx = 0; srgn_idx < rgn->srgn_cnt; srgn_idx++) {
+		srgn  = rgn->srgn_tbl + srgn_idx;
+
+		if (srgn->srgn_state == HPB_SRGN_ISSUED)
+			return -EPERM;
+	}
+	return 0;
+}
+
+static inline void ufshpb_add_lru_info(struct victim_select_info *lru_info,
+				       struct ufshpb_region *rgn)
+{
+	rgn->rgn_state = HPB_RGN_ACTIVE;
+	list_add_tail(&rgn->list_lru_rgn, &lru_info->lh_lru_rgn);
+	atomic_inc(&lru_info->active_cnt);
+}
+
+static inline void ufshpb_hit_lru_info(struct victim_select_info *lru_info,
+				       struct ufshpb_region *rgn)
+{
+	list_move_tail(&rgn->list_lru_rgn, &lru_info->lh_lru_rgn);
+}
+
+static struct ufshpb_region *ufshpb_victim_lru_info(struct ufshpb_lu *hpb)
+{
+	struct victim_select_info *lru_info = &hpb->lru_info;
+	struct ufshpb_region *rgn, *victim_rgn = NULL;
+
+	list_for_each_entry(rgn, &lru_info->lh_lru_rgn, list_lru_rgn) {
+		WARN_ON(!rgn);
+		if (ufshpb_check_issue_state_srgns(hpb, rgn))
+			continue;
+
+		victim_rgn = rgn;
+		break;
+	}
+
+	return victim_rgn;
+}
+
+static inline void ufshpb_cleanup_lru_info(struct victim_select_info *lru_info,
+					   struct ufshpb_region *rgn)
+{
+	list_del_init(&rgn->list_lru_rgn);
+	rgn->rgn_state = HPB_RGN_INACTIVE;
+	atomic_dec(&lru_info->active_cnt);
+}
+
+static inline void ufshpb_purge_active_subregion(struct ufshpb_lu *hpb,
+						 struct ufshpb_subregion *srgn)
+{
+	if (srgn->srgn_state != HPB_SRGN_UNUSED) {
+		ufshpb_put_map_ctx(hpb, srgn->mctx);
+		srgn->srgn_state = HPB_SRGN_UNUSED;
+		srgn->mctx = NULL;
+	}
+}
+
+static void __ufshpb_evict_region(struct ufshpb_lu *hpb,
+				  struct ufshpb_region *rgn)
+{
+	struct victim_select_info *lru_info;
+	struct ufshpb_subregion *srgn;
+	int srgn_idx;
+
+	lru_info = &hpb->lru_info;
+
+	dev_dbg(&hpb->hpb_lu_dev, "evict region %d\n", rgn->rgn_idx);
+
+	ufshpb_cleanup_lru_info(lru_info, rgn);
+
+	for (srgn_idx = 0; srgn_idx < rgn->srgn_cnt; srgn_idx++) {
+		srgn = rgn->srgn_tbl + srgn_idx;
+
+		ufshpb_purge_active_subregion(hpb, srgn);
+	}
+}
+
+static int ufshpb_evict_region(struct ufshpb_lu *hpb, struct ufshpb_region *rgn)
+{
+	unsigned long flags;
+	int ret = 0;
+
+	spin_lock_irqsave(&hpb->hpb_state_lock, flags);
+	if (rgn->rgn_state == HPB_RGN_PINNED) {
+		dev_warn(&hpb->hpb_lu_dev,
+			 "pinned region cannot drop-out. region %d\n",
+			 rgn->rgn_idx);
+		goto out;
+	}
+	if (!list_empty(&rgn->list_lru_rgn)) {
+		if (ufshpb_check_issue_state_srgns(hpb, rgn)) {
+			ret = -EBUSY;
+			goto out;
+		}
+
+		__ufshpb_evict_region(hpb, rgn);
+	}
+out:
+	spin_unlock_irqrestore(&hpb->hpb_state_lock, flags);
+	return ret;
+}
+
+static inline struct
+ufshpb_rsp_field *ufshpb_get_hpb_rsp(struct ufshcd_lrb *lrbp)
+{
+	return (struct ufshpb_rsp_field *)&lrbp->ucd_rsp_ptr->sr.sense_data_len;
+}
+
+static int ufshpb_issue_map_req(struct ufshpb_lu *hpb,
+				struct ufshpb_region *rgn,
+				struct ufshpb_subregion *srgn)
+{
+	struct ufshpb_req *map_req;
+	unsigned long flags;
+	int ret;
+	int err = -EAGAIN;
+	bool alloc_required = false;
+	enum HPB_RGN_STATE state = HPB_SRGN_INVALID;
+
+	spin_lock_irqsave(&hpb->hpb_state_lock, flags);
+	/*
+	 * Since the region state change occurs only in the map_work,
+	 * the state of the region cannot HPB_RGN_INACTIVE at this point.
+	 * The region state must be changed in the map_work
+	 */
+	WARN_ON(rgn->rgn_state == HPB_RGN_INACTIVE);
+
+	if (srgn->srgn_state == HPB_SRGN_UNUSED)
+		alloc_required = true;
+
+	/*
+	 * If the subregion is already ISSUED state,
+	 * a specific event (e.g., GC or wear-leveling, etc.) occurs in
+	 * the device and HPB response for map loading is received.
+	 * In this case, after finishing the HPB_READ_BUFFER,
+	 * the next HPB_READ_BUFFER is performed again to obtain the latest
+	 * map data.
+	 */
+	if (srgn->srgn_state == HPB_SRGN_ISSUED)
+		goto unlock_out;
+
+	srgn->srgn_state = HPB_SRGN_ISSUED;
+	spin_unlock_irqrestore(&hpb->hpb_state_lock, flags);
+
+	if (alloc_required) {
+		WARN_ON(srgn->mctx);
+		srgn->mctx = ufshpb_get_map_ctx(hpb);
+		if (!srgn->mctx) {
+			dev_notice(&hpb->hpb_lu_dev,
+			    "get map_ctx failed. region %d - %d\n",
+			    rgn->rgn_idx, srgn->srgn_idx);
+			state = HPB_SRGN_UNUSED;
+			goto change_srgn_state;
+		}
+	}
+
+	ufshpb_clear_dirty_bitmap(hpb, srgn);
+	map_req = ufshpb_get_map_req(hpb, srgn);
+	if (!map_req)
+		goto change_srgn_state;
+
+	ret = ufshpb_lu_get(hpb);
+	if (unlikely(ret)) {
+		dev_notice(&hpb->hpb_lu_dev,
+			   "%s: ufshpb_lu_get failed: %d", __func__, ret);
+		goto free_map_req;
+	}
+
+	ret = ufshpb_execute_map_req(hpb, map_req);
+	if (ret) {
+		dev_notice(&hpb->hpb_lu_dev,
+			   "%s: issue map_req failed: %d, region %d - %d\n",
+			   __func__, ret, srgn->rgn_idx, srgn->srgn_idx);
+		ufshpb_lu_put(hpb);
+		goto free_map_req;
+	}
+	return 0;
+
+free_map_req:
+	ufshpb_put_map_req(hpb, map_req);
+change_srgn_state:
+	spin_lock_irqsave(&hpb->hpb_state_lock, flags);
+	srgn->srgn_state = state;
+unlock_out:
+	spin_unlock_irqrestore(&hpb->hpb_state_lock, flags);
+	return err;
+}
+
+static int ufshpb_add_region(struct ufshpb_lu *hpb, struct ufshpb_region *rgn)
+{
+	struct ufshpb_region *victim_rgn;
+	struct victim_select_info *lru_info = &hpb->lru_info;
+	unsigned long flags;
+	int ret = 0;
+
+	spin_lock_irqsave(&hpb->hpb_state_lock, flags);
+	/*
+	 * If region belongs to lru_list, just move the region
+	 * to the front of lru list. because the state of the region
+	 * is already active-state
+	 */
+	if (!list_empty(&rgn->list_lru_rgn)) {
+		ufshpb_hit_lru_info(lru_info, rgn);
+		goto out;
+	}
+
+	if (rgn->rgn_state == HPB_RGN_INACTIVE) {
+		if (atomic_read(&lru_info->active_cnt)
+		    == lru_info->max_lru_active_cnt) {
+			/*
+			 * If the maximum number of active regions
+			 * is exceeded, evict the least recently used region.
+			 * This case may occur when the device responds
+			 * to the eviction information late.
+			 * It is okay to evict the least recently used region,
+			 * because the device could detect this region
+			 * by not issuing HPB_READ
+			 */
+			victim_rgn = ufshpb_victim_lru_info(hpb);
+			if (!victim_rgn) {
+				dev_warn(&hpb->hpb_lu_dev,
+				    "cannot get victim region error\n");
+				ret = -ENOMEM;
+				goto out;
+			}
+
+			dev_dbg(&hpb->hpb_lu_dev,
+				"LRU full (%d), choost victim %d\n",
+				atomic_read(&lru_info->active_cnt),
+				victim_rgn->rgn_idx);
+			__ufshpb_evict_region(hpb, victim_rgn);
+		}
+
+		/*
+		 * When a region is added to lru_info list_head,
+		 * it is guaranteed that the subregion has been
+		 * assigned all mctx. If failed, try to receive mctx again
+		 * without being added to lru_info list_head
+		 */
+		ufshpb_add_lru_info(lru_info, rgn);
+	}
+out:
+	spin_unlock_irqrestore(&hpb->hpb_state_lock, flags);
+	return ret;
+}
+
+static void ufshpb_rsp_req_region_update(struct ufshpb_lu *hpb,
+					 struct ufshpb_rsp_field *rsp_field)
+{
+	int i, rgn_idx, srgn_idx;
+
+	/*
+	 * If the active region and the inactive region are the same,
+	 * we will inactivate this region.
+	 * The device could check this (region inactivated) and
+	 * will response the proper active region information
+	 */
+	spin_lock(&hpb->rsp_list_lock);
+	for (i = 0; i < rsp_field->active_rgn_cnt; i++) {
+		rgn_idx =
+			be16_to_cpu(rsp_field->hpb_active_field[i].active_rgn);
+		srgn_idx =
+			be16_to_cpu(rsp_field->hpb_active_field[i].active_srgn);
+
+		dev_dbg(&hpb->hpb_lu_dev, "activate(%d) region %d - %d\n",
+			i, rgn_idx, srgn_idx);
+		ufshpb_update_active_info(hpb, rgn_idx, srgn_idx);
+		atomic_inc(&hpb->stats.rb_active_cnt);
+	}
+
+	for (i = 0; i < rsp_field->inactive_rgn_cnt; i++) {
+		rgn_idx = be16_to_cpu(rsp_field->hpb_inactive_field[i]);
+		dev_dbg(&hpb->hpb_lu_dev, "inactivate(%d) region %d\n",
+			i, rgn_idx);
+		ufshpb_update_inactive_info(hpb, rgn_idx);
+		atomic_inc(&hpb->stats.rb_inactive_cnt);
+	}
+	spin_unlock(&hpb->rsp_list_lock);
+
+	dev_dbg(&hpb->hpb_lu_dev, "Noti: #ACT %u #INACT %u\n",
+		rsp_field->active_rgn_cnt, rsp_field->inactive_rgn_cnt);
+
+	queue_work(ufshpb_drv.ufshpb_wq, &hpb->map_work);
+}
+
+/* routine : isr (ufs) */
+static void ufshpb_rsp_upiu(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
+{
+	struct ufshpb_lu *hpb;
+	struct ufshpb_rsp_field *rsp_field;
+	int data_seg_len, ret;
+
+	data_seg_len = be32_to_cpu(lrbp->ucd_rsp_ptr->header.dword_2)
+		& MASK_RSP_UPIU_DATA_SEG_LEN;
+
+	/* To flush remained rsp_list, we queue the map_work task */
+	if (!data_seg_len) {
+		if (!ufshpb_is_general_lun(lrbp->lun))
+			return;
+
+		hpb = ufshpb_get_hpb_data(lrbp->cmd);
+		ret = ufshpb_lu_get(hpb);
+		if (ret)
+			return;
+
+		if (!ufshpb_is_empty_rsp_lists(hpb))
+			queue_work(ufshpb_drv.ufshpb_wq, &hpb->map_work);
+
+		goto put_hpb;
+	}
+
+	/* Check HPB_UPDATE_ALERT */
+	if (!(lrbp->ucd_rsp_ptr->header.dword_2 &
+	      UPIU_HEADER_DWORD(0, 2, 0, 0)))
+		return;
+
+	rsp_field = ufshpb_get_hpb_rsp(lrbp);
+	if (ufshpb_may_field_valid(hba, lrbp, rsp_field))
+		return;
+
+	hpb = ufshpb_get_hpb_data(lrbp->cmd);
+	ret = ufshpb_lu_get(hpb);
+	if (ret)
+		return;
+
+	atomic_inc(&hpb->stats.rb_noti_cnt);
+
+	switch (rsp_field->hpb_type) {
+	case HPB_RSP_REQ_REGION_UPDATE:
+		WARN_ON(data_seg_len != DEV_DATA_SEG_LEN);
+		ufshpb_rsp_req_region_update(hpb, rsp_field);
+		break;
+	case HPB_RSP_DEV_RESET:
+		dev_warn(&hpb->hpb_lu_dev,
+			 "UFS device lost HPB information during PM.\n");
+		break;
+	default:
+		dev_notice(&hpb->hpb_lu_dev, "hpb_type is not available: %d\n",
+			   rsp_field->hpb_type);
+		break;
+	}
+put_hpb:
+	ufshpb_lu_put(hpb);
+}
+
+static void ufshpb_add_active_list(struct ufshpb_lu *hpb,
+				   struct ufshpb_region *rgn,
+				   struct ufshpb_subregion *srgn)
+{
+	if (!list_empty(&rgn->list_inact_rgn))
+		return;
+
+	if (!list_empty(&srgn->list_act_srgn)) {
+		list_move(&srgn->list_act_srgn, &hpb->lh_act_srgn);
+		return;
+	}
+
+	list_add(&srgn->list_act_srgn, &hpb->lh_act_srgn);
+}
+
+static void ufshpb_add_pending_evict_list(struct ufshpb_lu *hpb,
+				    struct ufshpb_region *rgn,
+				    struct list_head *pending_list)
+{
+	struct ufshpb_subregion *srgn;
+	int srgn_idx;
+
+	if (!list_empty(&rgn->list_inact_rgn))
+		return;
+
+	for (srgn_idx = 0; srgn_idx < rgn->srgn_cnt; srgn_idx++) {
+		srgn = rgn->srgn_tbl + srgn_idx;
+
+		if (!list_empty(&srgn->list_act_srgn))
+			return;
+	}
+
+	list_add_tail(&rgn->list_inact_rgn, pending_list);
+}
+
+static void ufshpb_run_active_subregion_list(struct ufshpb_lu *hpb)
+{
+	struct ufshpb_region *rgn;
+	struct ufshpb_subregion *srgn;
+	unsigned long flags;
+	int ret = 0;
+
+	spin_lock_irqsave(&hpb->rsp_list_lock, flags);
+	while ((srgn = list_first_entry_or_null(&hpb->lh_act_srgn,
+						struct ufshpb_subregion,
+						list_act_srgn))) {
+		list_del_init(&srgn->list_act_srgn);
+		spin_unlock_irqrestore(&hpb->rsp_list_lock, flags);
+
+		rgn = hpb->rgn_tbl + srgn->rgn_idx;
+		ret = ufshpb_add_region(hpb, rgn);
+		if (ret)
+			break;
+
+		ret = ufshpb_issue_map_req(hpb, rgn, srgn);
+		if (ret) {
+			dev_notice(&hpb->hpb_lu_dev,
+			    "issue map_req failed. ret %d, region %d - %d\n",
+			    ret, rgn->rgn_idx, srgn->srgn_idx);
+			break;
+		}
+		spin_lock_irqsave(&hpb->rsp_list_lock, flags);
+	}
+
+	if (ret) {
+		dev_notice(&hpb->hpb_lu_dev, "region %d - %d, will retry\n",
+			   rgn->rgn_idx, srgn->srgn_idx);
+		spin_lock_irqsave(&hpb->rsp_list_lock, flags);
+		ufshpb_add_active_list(hpb, rgn, srgn);
+	}
+	spin_unlock_irqrestore(&hpb->rsp_list_lock, flags);
+}
+
+static void ufshpb_run_inactive_region_list(struct ufshpb_lu *hpb)
+{
+	struct ufshpb_region *rgn;
+	unsigned long flags;
+	int ret;
+	LIST_HEAD(pending_list);
+
+	spin_lock_irqsave(&hpb->rsp_list_lock, flags);
+	while ((rgn = list_first_entry_or_null(&hpb->lh_inact_rgn,
+					       struct ufshpb_region,
+					       list_inact_rgn))) {
+		list_del_init(&rgn->list_inact_rgn);
+		spin_unlock_irqrestore(&hpb->rsp_list_lock, flags);
+
+		ret = ufshpb_evict_region(hpb, rgn);
+		if (ret) {
+			spin_lock_irqsave(&hpb->rsp_list_lock, flags);
+			ufshpb_add_pending_evict_list(hpb, rgn, &pending_list);
+			spin_unlock_irqrestore(&hpb->rsp_list_lock, flags);
+		}
+
+		spin_lock_irqsave(&hpb->rsp_list_lock, flags);
+	}
+
+	list_splice(&pending_list, &hpb->lh_inact_rgn);
+	spin_unlock_irqrestore(&hpb->rsp_list_lock, flags);
+}
+
+static void ufshpb_map_work_handler(struct work_struct *work)
+{
+	struct ufshpb_lu *hpb;
+	int ret;
+
+	hpb = container_of(work, struct ufshpb_lu, map_work);
+	ret = ufshpb_lu_get(hpb);
+	if (ret) {
+		dev_info(&hpb->hpb_lu_dev, "%s: exit, state %d\n",
+			 __func__, ufshpb_get_state(hpb));
+		return;
+	}
+
+	ufshpb_run_inactive_region_list(hpb);
+	ufshpb_run_active_subregion_list(hpb);
+
+	ufshpb_lu_put(hpb);
+}
+
+/*
+ * this function doesn't need to hold lock due to be called in init.
+ * (hpb_state_lock, rsp_list_lock, etc..)
+ */
+static int ufshpb_init_pinned_active_region(struct ufs_hba *hba,
+					    struct ufshpb_lu *hpb,
+					    struct ufshpb_region *rgn)
+{
+	struct ufshpb_subregion *srgn;
+	int srgn_idx, i;
+	int err = 0;
+
+	for (srgn_idx = 0; srgn_idx < rgn->srgn_cnt; srgn_idx++) {
+		srgn = rgn->srgn_tbl + srgn_idx;
+
+		srgn->mctx = ufshpb_get_map_ctx(hpb);
+		srgn->srgn_state = HPB_SRGN_INVALID;
+		if (!srgn->mctx) {
+			dev_err(hba->dev,
+				"alloc mctx for pinned region failed\n");
+			goto release;
+		}
+
+		list_add_tail(&srgn->list_act_srgn, &hpb->lh_act_srgn);
+	}
+
+	rgn->rgn_state = HPB_RGN_PINNED;
+	return 0;
+
+release:
+	for (i = 0; i < srgn_idx; i++) {
+		srgn = rgn->srgn_tbl + i;
+		ufshpb_put_map_ctx(hpb, srgn->mctx);
+	}
+	return err;
+}
+
 static void ufshpb_init_subregion_tbl(struct ufshpb_lu *hpb,
 				      struct ufshpb_region *rgn)
 {
@@ -67,6 +884,8 @@ static void ufshpb_init_subregion_tbl(struct ufshpb_lu *hpb,
 	for (srgn_idx = 0; srgn_idx < rgn->srgn_cnt; srgn_idx++) {
 		struct ufshpb_subregion *srgn = rgn->srgn_tbl + srgn_idx;
 
+		INIT_LIST_HEAD(&srgn->list_act_srgn);
+
 		srgn->rgn_idx = rgn->rgn_idx;
 		srgn->srgn_idx = srgn_idx;
 		srgn->srgn_state = HPB_SRGN_UNUSED;
@@ -99,6 +918,8 @@ static void ufshpb_init_lu_parameter(struct ufs_hba *hba,
 	hpb->lu_pinned_end = hpb_lu_info->num_pinned ?
 		(hpb_lu_info->pinned_start + hpb_lu_info->num_pinned - 1)
 		: PINNED_NOT_SET;
+	hpb->lru_info.max_lru_active_cnt =
+		hpb_lu_info->max_active_rgns - hpb_lu_info->num_pinned;
 
 	rgn_mem_size = (1ULL << hpb_dev_info->rgn_size) * HPB_RGN_SIZE_UNIT
 		/ HPB_ENTRY_BLOCK_SIZE * HPB_ENTRY_SIZE;
@@ -152,6 +973,9 @@ static int ufshpb_alloc_region_tbl(struct ufs_hba *hba, struct ufshpb_lu *hpb)
 		rgn = rgn_table + rgn_idx;
 		rgn->rgn_idx = rgn_idx;
 
+		INIT_LIST_HEAD(&rgn->list_inact_rgn);
+		INIT_LIST_HEAD(&rgn->list_lru_rgn);
+
 		if (rgn_idx == hpb->rgns_per_lu - 1)
 			srgn_cnt = ((hpb->srgns_per_lu - 1) %
 				    hpb->srgns_per_rgn) + 1;
@@ -161,7 +985,13 @@ static int ufshpb_alloc_region_tbl(struct ufs_hba *hba, struct ufshpb_lu *hpb)
 			goto release_srgn_table;
 		ufshpb_init_subregion_tbl(hpb, rgn);
 
-		rgn->rgn_state = HPB_RGN_INACTIVE;
+		if (ufshpb_is_pinned_region(hpb, rgn_idx)) {
+			ret = ufshpb_init_pinned_active_region(hba, hpb, rgn);
+			if (ret)
+				goto release_srgn_table;
+		} else {
+			rgn->rgn_state = HPB_RGN_INACTIVE;
+		}
 	}
 
 	return 0;
@@ -185,7 +1015,10 @@ static void ufshpb_destroy_subregion_tbl(struct ufshpb_lu *hpb,
 		struct ufshpb_subregion *srgn;
 
 		srgn = rgn->srgn_tbl + srgn_idx;
-		srgn->srgn_state = HPB_SRGN_UNUSED;
+		if (srgn->srgn_state != HPB_SRGN_UNUSED) {
+			srgn->srgn_state = HPB_SRGN_UNUSED;
+			ufshpb_put_map_ctx(hpb, srgn->mctx);
+		}
 	}
 }
 
@@ -215,8 +1048,36 @@ static int ufshpb_lu_hpb_init(struct ufs_hba *hba, struct ufshpb_lu *hpb,
 	int ret;
 
 	spin_lock_init(&hpb->hpb_state_lock);
+	spin_lock_init(&hpb->rsp_list_lock);
+
+	INIT_LIST_HEAD(&hpb->lru_info.lh_lru_rgn);
+	INIT_LIST_HEAD(&hpb->lh_act_srgn);
+	INIT_LIST_HEAD(&hpb->lh_inact_rgn);
+	INIT_LIST_HEAD(&hpb->list_hpb_lu);
+
+	INIT_WORK(&hpb->map_work, ufshpb_map_work_handler);
+
+	hpb->map_req_cache = kmem_cache_create("ufshpb_req_cache",
+			  sizeof(struct ufshpb_req), 0, 0, NULL);
+	if (!hpb->map_req_cache) {
+		dev_err(hba->dev, "ufshpb(%d) ufshpb_req_cache create fail",
+			hpb->lun);
+		return -ENOMEM;
+	}
+
+	hpb->m_page_cache = kmem_cache_create("ufshpb_m_page_cache",
+			  sizeof(struct page *) * hpb->pages_per_srgn,
+			  0, 0, NULL);
+	if (!hpb->m_page_cache) {
+		dev_err(hba->dev, "ufshpb(%d) ufshpb_m_page_cache create fail",
+			hpb->lun);
+		ret = -ENOMEM;
+		goto release_req_cache;
+	}
 
 	ret = ufshpb_alloc_region_tbl(hba, hpb);
+	if (ret)
+		goto release_m_page_cache;
 
 	ret = ufshpb_create_sysfs(hba, hpb);
 	if (ret)
@@ -226,6 +1087,10 @@ static int ufshpb_lu_hpb_init(struct ufs_hba *hba, struct ufshpb_lu *hpb,
 
 release_rgn_table:
 	ufshpb_destroy_region_tbl(hpb);
+release_m_page_cache:
+	kmem_cache_destroy(hpb->m_page_cache);
+release_req_cache:
+	kmem_cache_destroy(hpb->map_req_cache);
 	return ret;
 }
 
@@ -257,10 +1122,42 @@ static struct ufshpb_lu *ufshpb_alloc_hpb_lu(struct ufs_hba *hba, int lun,
 	return NULL;
 }
 
+static void ufshpb_discard_rsp_lists(struct ufshpb_lu *hpb)
+{
+	struct ufshpb_region *rgn, *next_rgn;
+	struct ufshpb_subregion *srgn, *next_srgn;
+	unsigned long flags;
+
+	/*
+	 * If the device reset occurred, the remained HPB region information
+	 * may be stale. Therefore, by dicarding the lists of HPB response
+	 * that remained after reset, it prevents unnecessary work.
+	 */
+	spin_lock_irqsave(&hpb->rsp_list_lock, flags);
+	list_for_each_entry_safe(rgn, next_rgn, &hpb->lh_inact_rgn,
+				 list_inact_rgn)
+		list_del_init(&rgn->list_inact_rgn);
+
+	list_for_each_entry_safe(srgn, next_srgn, &hpb->lh_act_srgn,
+				 list_act_srgn)
+		list_del_init(&srgn->list_act_srgn);
+	spin_unlock_irqrestore(&hpb->rsp_list_lock, flags);
+}
+
+static inline void ufshpb_cancel_jobs(struct ufshpb_lu *hpb)
+{
+	cancel_work_sync(&hpb->map_work);
+}
+
 static void ufshpb_lu_release(struct ufshpb_lu *hpb)
 {
+	ufshpb_cancel_jobs(hpb);
+
 	ufshpb_destroy_region_tbl(hpb);
 
+	kmem_cache_destroy(hpb->map_req_cache);
+	kmem_cache_destroy(hpb->m_page_cache);
+
 	list_del_init(&hpb->list_hpb_lu);
 }
 
@@ -347,6 +1244,9 @@ static void ufshpb_reset_host(struct ufs_hba *hba)
 		dev_info(&hpb->hpb_lu_dev, "ufshpb run reset_host");
 
 		ufshpb_set_state(hpb, HPB_RESET);
+		ufshpb_cancel_jobs(hpb);
+		ufshpb_discard_rsp_lists(hpb);
+
 		ufshpb_lu_put(hpb);
 	}
 }
@@ -361,6 +1261,7 @@ static void ufshpb_suspend(struct ufs_hba *hba)
 
 		dev_info(&hpb->hpb_lu_dev, "ufshpb goto suspend");
 		ufshpb_set_state(hpb, HPB_SUSPEND);
+		ufshpb_cancel_jobs(hpb);
 
 		ufshpb_lu_put(hpb);
 	}
@@ -376,6 +1277,9 @@ static void ufshpb_resume(struct ufs_hba *hba)
 
 		dev_info(&hpb->hpb_lu_dev, "ufshpb resume");
 		ufshpb_set_state(hpb, HPB_PRESENT);
+		if (!ufshpb_is_empty_rsp_lists(hpb))
+			queue_work(ufshpb_drv.ufshpb_wq, &hpb->map_work);
+
 		ufshpb_lu_put(hpb);
 	}
 }
@@ -617,6 +1521,8 @@ static void ufshpb_scan_hpb_lu(struct ufs_hba *hba,
 	struct scsi_device *sdev;
 	struct ufshpb_lu *hpb;
 	int find_hpb_lu = 0;
+	int tot_active_srgn_pages = 0;
+	int pool_size;
 	int ret;
 
 	INIT_LIST_HEAD(&ufshpb_drv.lh_hpb_lu);
@@ -637,6 +1543,9 @@ static void ufshpb_scan_hpb_lu(struct ufs_hba *hba,
 		if (!hpb)
 			continue;
 
+		tot_active_srgn_pages += hpb_lu_info.max_active_rgns *
+				hpb->srgns_per_rgn * hpb->pages_per_srgn;
+
 		hpb->sdev_ufs_lu = sdev;
 		sdev->hostdata = hpb;
 
@@ -648,11 +1557,31 @@ static void ufshpb_scan_hpb_lu(struct ufs_hba *hba,
 		return;
 
 	ufshpb_check_hpb_reset_query(hba);
+
+	pool_size = DIV_ROUND_UP(ufshpb_host_map_kbytes * 1024, PAGE_SIZE);
+	if (pool_size > tot_active_srgn_pages) {
+		dev_info(hba->dev,
+			"reset pool_size to %lu KB.\n",
+			tot_active_srgn_pages * PAGE_SIZE / 1024);
+		mempool_resize(ufshpb_drv.ufshpb_mctx_pool,
+			       tot_active_srgn_pages);
+		mempool_resize(ufshpb_drv.ufshpb_page_pool,
+			       tot_active_srgn_pages);
+	}
+
 	dev_set_drvdata(&hba->ufsf.hpb_dev, &ufshpb_drv);
 
 	list_for_each_entry(hpb, &ufshpb_drv.lh_hpb_lu, list_hpb_lu) {
 		dev_info(&hpb->hpb_lu_dev, "set state to present\n");
 		ufshpb_set_state(hpb, HPB_PRESENT);
+
+		if ((hpb->lu_pinned_end - hpb->lu_pinned_start) > 0) {
+			dev_info(&hpb->hpb_lu_dev,
+			    "loading pinned regions %d - %d\n",
+			    hpb->lu_pinned_start, hpb->lu_pinned_end);
+			queue_work(ufshpb_drv.ufshpb_wq,
+				&hpb->map_work);
+		}
 	}
 }
 
@@ -719,6 +1648,8 @@ static int ufshpb_remove(struct device *dev)
 		sdev = hpb->sdev_ufs_lu;
 		sdev->hostdata = NULL;
 
+		ufshpb_cancel_jobs(hpb);
+
 		device_del(&hpb->hpb_lu_dev);
 
 		dev_info(&hpb->hpb_lu_dev, "hpb_lu_dev refcnt %d\n",
@@ -744,10 +1675,10 @@ static struct ufshpb_driver ufshpb_drv = {
 		.reset_host = ufshpb_reset_host,
 		.suspend = ufshpb_suspend,
 		.resume = ufshpb_resume,
+		.rsp_upiu = ufshpb_rsp_upiu,
 	},
 };
 
-unsigned int ufshpb_host_map_kbytes = 1 * 1024;
 module_param(ufshpb_host_map_kbytes, uint, 0644);
 MODULE_PARM_DESC(ufshpb_host_map_kbytes,
 	 "ufshpb host mapping memory kilo-bytes for ufshpb memory-pool");
@@ -755,17 +1686,70 @@ MODULE_PARM_DESC(ufshpb_host_map_kbytes,
 static int __init ufshpb_init(void)
 {
 	int ret;
+	unsigned int pool_size;
+
+	ufshpb_drv.ufshpb_mctx_cache = kmem_cache_create("ufshpb_mctx_cache",
+					sizeof(struct ufshpb_map_ctx),
+					0, 0, NULL);
+	if (!ufshpb_drv.ufshpb_mctx_cache) {
+		pr_err("ufshpb: cannot init mctx cache\n");
+		return -ENOMEM;
+	}
+
+	pool_size = DIV_ROUND_UP(ufshpb_host_map_kbytes * 1024, PAGE_SIZE);
+	pr_info("%s:%d ufshpb_host_map_kbytes %u pool_size %u\n",
+	       __func__, __LINE__, ufshpb_host_map_kbytes, pool_size);
+
+	ufshpb_drv.ufshpb_mctx_pool = mempool_create_slab_pool(
+				     pool_size, ufshpb_drv.ufshpb_mctx_cache);
+	if (!ufshpb_drv.ufshpb_mctx_pool) {
+		pr_err("ufshpb: cannot init mctx pool\n");
+		ret = -ENOMEM;
+		goto release_mctx_cache;
+	}
+
+	ufshpb_drv.ufshpb_page_pool = mempool_create_page_pool(pool_size, 0);
+	if (!ufshpb_drv.ufshpb_page_pool) {
+		pr_err("ufshpb: cannot init page pool\n");
+		ret = -ENOMEM;
+		goto release_mctx_pool;
+	}
+
+	ufshpb_drv.ufshpb_wq = alloc_workqueue("ufshpb-wq",
+					WQ_UNBOUND | WQ_MEM_RECLAIM, 0);
+	if (!ufshpb_drv.ufshpb_wq) {
+		pr_err("ufshpb: alloc workqueue failed\n");
+		ret = -ENOMEM;
+		goto release_page_pool;
+	}
 
 	ret = driver_register(&ufshpb_drv.drv);
-	if (ret)
+	if (ret) {
 		pr_err("ufshpb: driver register failed\n");
+		goto release_wq;
+	}
 
+	return 0;
+release_wq:
+	destroy_workqueue(ufshpb_drv.ufshpb_wq);
+release_page_pool:
+	mempool_destroy(ufshpb_drv.ufshpb_page_pool);
+release_mctx_pool:
+	mempool_destroy(ufshpb_drv.ufshpb_mctx_pool);
+release_mctx_cache:
+	kmem_cache_destroy(ufshpb_drv.ufshpb_mctx_cache);
 	return ret;
 }
 
 static void __exit ufshpb_exit(void)
 {
 	driver_unregister(&ufshpb_drv.drv);
+
+	mempool_destroy(ufshpb_drv.ufshpb_page_pool);
+	mempool_destroy(ufshpb_drv.ufshpb_mctx_pool);
+	kmem_cache_destroy(ufshpb_drv.ufshpb_mctx_cache);
+
+	destroy_workqueue(ufshpb_drv.ufshpb_wq);
 }
 
 MODULE_AUTHOR("Yongmyong Lee <ymhungry.lee@samsung.com>");
diff --git a/drivers/scsi/ufs/ufshpb.h b/drivers/scsi/ufs/ufshpb.h
index eaa4a3e035b1..d9c27348d354 100644
--- a/drivers/scsi/ufs/ufshpb.h
+++ b/drivers/scsi/ufs/ufshpb.h
@@ -101,10 +101,36 @@ struct ufshpb_lu_info {
 	int max_active_rgns;
 };
 
+struct ufshpb_active_field {
+	__be16 active_rgn;
+	__be16 active_srgn;
+} __packed;
+
+struct ufshpb_rsp_field {
+	__be16 sense_data_len;
+	u8 desc_type;
+	u8 additional_len;
+	u8 hpb_type;
+	u8 reserved;
+	u8 active_rgn_cnt;
+	u8 inactive_rgn_cnt;
+	struct ufshpb_active_field hpb_active_field[2];
+	__be16 hpb_inactive_field[2];
+} __packed;
+
+struct ufshpb_map_ctx {
+	struct page **m_page;
+	unsigned long *ppn_dirty;
+};
+
 struct ufshpb_subregion {
+	struct ufshpb_map_ctx *mctx;
 	enum HPB_SRGN_STATE srgn_state;
 	int rgn_idx;
 	int srgn_idx;
+
+	/* below information is used by rsp_list */
+	struct list_head list_act_srgn;
 };
 
 struct ufshpb_region {
@@ -112,6 +138,39 @@ struct ufshpb_region {
 	enum HPB_RGN_STATE rgn_state;
 	int rgn_idx;
 	int srgn_cnt;
+
+	/* below information is used by rsp_list */
+	struct list_head list_inact_rgn;
+
+	/* below information is used by lru */
+	struct list_head list_lru_rgn;
+};
+
+/**
+ * struct ufshpb_req - UFSHPB READ BUFFER (for caching map) request structure
+ * @req: block layer request for READ BUFFER
+ * @bio: bio for holding map page
+ * @hpb: ufshpb_lu structure that related to the L2P map
+ * @mctx: L2P map information
+ * @rgn_idx: target region index
+ * @srgn_idx: target sub-region index
+ * @lun: target logical unit number
+ */
+struct ufshpb_req {
+	struct request *req;
+	struct bio *bio;
+	struct ufshpb_lu *hpb;
+	struct ufshpb_map_ctx *mctx;
+
+	unsigned int rgn_idx;
+	unsigned int srgn_idx;
+	unsigned int lun;
+};
+
+struct victim_select_info {
+	struct list_head lh_lru_rgn;
+	int max_lru_active_cnt; /* supported hpb #region - pinned #region */
+	atomic_t active_cnt;
 };
 
 struct ufshpb_stats {
@@ -134,6 +193,16 @@ struct ufshpb_lu {
 	spinlock_t hpb_state_lock;
 	atomic_t hpb_state; /* hpb_state_lock */
 
+	spinlock_t rsp_list_lock;
+	struct list_head lh_act_srgn; /* rsp_list_lock */
+	struct list_head lh_inact_rgn; /* rsp_list_lock */
+
+	/* cached L2P map management worker */
+	struct work_struct map_work;
+
+	/* for selecting victim */
+	struct victim_select_info lru_info;
+
 	/* pinned region information */
 	u32 lu_pinned_start;
 	u32 lu_pinned_end;
@@ -152,6 +221,9 @@ struct ufshpb_lu {
 
 	struct ufshpb_stats stats;
 
+	struct kmem_cache *map_req_cache;
+	struct kmem_cache *m_page_cache;
+
 	struct ufsf_feature_info *ufsf;
 	struct list_head list_hpb_lu;
 };
-- 
2.17.1

[RFC PATCH v3 5/5] scsi: ufs: Prepare HPB read for cached sub-region

[Daejun Park]

This patch changes the read I/O to the HPB read I/O.

If the logical address of the read I/O belongs to active sub-region, the
HPB driver modifies the read I/O command to HPB read. It modifies the upiu
command of UFS instead of modifying the existing SCSI command.

In the HPB version 1.0, the maximum read I/O size that can be converted to
HPB read is 4KB.

The dirty map of the active sub-region prevents an incorrect HPB read that
has stale physical page number which is updated by previous write I/O.

Signed-off-by: Daejun Park <daejun7.park@samsung.com>
---
 drivers/scsi/ufs/ufshpb.c | 235 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 235 insertions(+)

diff --git a/drivers/scsi/ufs/ufshpb.c b/drivers/scsi/ufs/ufshpb.c
index e1af4c2ed9ab..7c9efa46faa1 100644
--- a/drivers/scsi/ufs/ufshpb.c
+++ b/drivers/scsi/ufs/ufshpb.c
@@ -26,6 +26,22 @@ static inline int ufshpb_is_valid_srgn(struct ufshpb_region *rgn,
 		srgn->srgn_state == HPB_SRGN_VALID;
 }
 
+static inline bool ufshpb_is_read_cmd(struct scsi_cmnd *cmd)
+{
+	return req_op(cmd->request) == REQ_OP_READ;
+}
+
+static inline bool ufshpb_is_write_discard_cmd(struct scsi_cmnd *cmd)
+{
+	return op_is_write(req_op(cmd->request)) ||
+	       op_is_discard(req_op(cmd->request));
+}
+
+static inline bool ufshpb_is_support_chunk(int transfer_len)
+{
+	return transfer_len <= HPB_MULTI_CHUNK_HIGH;
+}
+
 static inline bool ufshpb_is_general_lun(int lun)
 {
 	return lun < UFS_UPIU_MAX_UNIT_NUM_ID;
@@ -117,6 +133,224 @@ static inline void ufshpb_lu_put(struct ufshpb_lu *hpb)
 	put_device(&hpb->hpb_lu_dev);
 }
 
+static inline u32 ufshpb_get_lpn(struct scsi_cmnd *cmnd)
+{
+	return blk_rq_pos(cmnd->request) >>
+		(ilog2(cmnd->device->sector_size) - 9);
+}
+
+static inline unsigned int ufshpb_get_len(struct scsi_cmnd *cmnd)
+{
+	return blk_rq_sectors(cmnd->request) >>
+		(ilog2(cmnd->device->sector_size) - 9);
+}
+
+static void ufshpb_set_ppn_dirty(struct ufshpb_lu *hpb, int rgn_idx,
+			     int srgn_idx, int srgn_offset, int cnt)
+{
+	struct ufshpb_region *rgn;
+	struct ufshpb_subregion *srgn;
+	int set_bit_len;
+	int bitmap_len = hpb->entries_per_srgn;
+
+next_srgn:
+	rgn = hpb->rgn_tbl + rgn_idx;
+	srgn = rgn->srgn_tbl + srgn_idx;
+
+	if ((srgn_offset + cnt) > bitmap_len)
+		set_bit_len = bitmap_len - srgn_offset;
+	else
+		set_bit_len = cnt;
+
+	if (rgn->rgn_state != HPB_RGN_INACTIVE &&
+	    srgn->srgn_state == HPB_SRGN_VALID)
+		bitmap_set(srgn->mctx->ppn_dirty, srgn_offset, set_bit_len);
+
+	srgn_offset = 0;
+	if (++srgn_idx == hpb->srgns_per_rgn) {
+		srgn_idx = 0;
+		rgn_idx++;
+	}
+
+	cnt -= set_bit_len;
+	if (cnt > 0)
+		goto next_srgn;
+
+	WARN_ON(cnt < 0);
+}
+
+static bool ufshpb_test_ppn_dirty(struct ufshpb_lu *hpb, int rgn_idx,
+				   int srgn_idx, int srgn_offset, int cnt)
+{
+	struct ufshpb_region *rgn;
+	struct ufshpb_subregion *srgn;
+	int bitmap_len = hpb->entries_per_srgn;
+	int bit_len;
+
+next_srgn:
+	rgn = hpb->rgn_tbl + rgn_idx;
+	srgn = rgn->srgn_tbl + srgn_idx;
+
+	if (!ufshpb_is_valid_srgn(rgn, srgn))
+		return true;
+
+	/*
+	 * If the region state is active, mctx must be allocated.
+	 * In this case, check whether the region is evicted or
+	 * mctx allcation fail.
+	 */
+	WARN_ON(!srgn->mctx);
+
+	if ((srgn_offset + cnt) > bitmap_len)
+		bit_len = bitmap_len - srgn_offset;
+	else
+		bit_len = cnt;
+
+	if (find_next_bit(srgn->mctx->ppn_dirty,
+			  bit_len, srgn_offset) >= srgn_offset)
+		return true;
+
+	srgn_offset = 0;
+	if (++srgn_idx == hpb->srgns_per_rgn) {
+		srgn_idx = 0;
+		rgn_idx++;
+	}
+
+	cnt -= bit_len;
+	if (cnt > 0)
+		goto next_srgn;
+
+	return false;
+}
+
+static u64 ufshpb_get_ppn(struct ufshpb_lu *hpb,
+			  struct ufshpb_map_ctx *mctx, int pos, int *error)
+{
+	u64 *ppn_table;
+	struct page *page;
+	int index, offset;
+
+	index = pos / (PAGE_SIZE / HPB_ENTRY_SIZE);
+	offset = pos % (PAGE_SIZE / HPB_ENTRY_SIZE);
+
+	page = mctx->m_page[index];
+	if (unlikely(!page)) {
+		*error = -ENOMEM;
+		dev_err(&hpb->hpb_lu_dev,
+			"error. cannot find page in mctx\n");
+		return 0;
+	}
+
+	ppn_table = page_address(page);
+	if (unlikely(!ppn_table)) {
+		*error = -ENOMEM;
+		dev_err(&hpb->hpb_lu_dev, "error. cannot get ppn_table\n");
+		return 0;
+	}
+
+	return ppn_table[offset];
+}
+
+static inline void
+ufshpb_get_pos_from_lpn(struct ufshpb_lu *hpb, unsigned long lpn, int *rgn_idx,
+			int *srgn_idx, int *offset)
+{
+	int rgn_offset;
+
+	*rgn_idx = lpn >> hpb->entries_per_rgn_shift;
+	rgn_offset = lpn & hpb->entries_per_rgn_mask;
+	*srgn_idx = rgn_offset >> hpb->entries_per_srgn_shift;
+	*offset = rgn_offset & hpb->entries_per_srgn_mask;
+}
+
+static void
+ufshpb_set_hpb_read_to_upiu(struct ufshpb_lu *hpb, struct ufshcd_lrb *lrbp,
+				  u32 lpn, u64 ppn,  unsigned int transfer_len)
+{
+	unsigned char *cdb = lrbp->ucd_req_ptr->sc.cdb;
+
+	cdb[0] = UFSHPB_READ;
+
+	put_unaligned_be64(ppn, &cdb[6]);
+	cdb[14] = transfer_len;
+}
+
+/* routine : READ10 -> HPB_READ  */
+static void ufshpb_prep_fn(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
+{
+	struct ufshpb_lu *hpb;
+	struct ufshpb_region *rgn;
+	struct ufshpb_subregion *srgn;
+	struct scsi_cmnd *cmd = lrbp->cmd;
+	u32 lpn;
+	u64 ppn;
+	unsigned long flags;
+	int transfer_len, rgn_idx, srgn_idx, srgn_offset;
+	int err = 0;
+
+	hpb = ufshpb_get_hpb_data(cmd);
+	err = ufshpb_lu_get(hpb);
+	if (unlikely(err))
+		return;
+
+	WARN_ON(hpb->lun != cmd->device->lun);
+	if (!ufshpb_is_write_discard_cmd(cmd) &&
+	    !ufshpb_is_read_cmd(cmd))
+		goto put_hpb;
+
+	transfer_len = ufshpb_get_len(cmd);
+	if (unlikely(!transfer_len))
+		goto put_hpb;
+
+	lpn = ufshpb_get_lpn(cmd);
+	ufshpb_get_pos_from_lpn(hpb, lpn, &rgn_idx, &srgn_idx, &srgn_offset);
+	rgn = hpb->rgn_tbl + rgn_idx;
+	srgn = rgn->srgn_tbl + srgn_idx;
+
+	/* If command type is WRITE or DISCARD, set bitmap as drity */
+	if (ufshpb_is_write_discard_cmd(cmd)) {
+		spin_lock_irqsave(&hpb->hpb_state_lock, flags);
+		ufshpb_set_ppn_dirty(hpb, rgn_idx, srgn_idx, srgn_offset,
+				 transfer_len);
+		spin_unlock_irqrestore(&hpb->hpb_state_lock, flags);
+		goto put_hpb;
+	}
+
+	WARN_ON(!ufshpb_is_read_cmd(cmd));
+
+	if (!ufshpb_is_support_chunk(transfer_len))
+		goto put_hpb;
+
+	spin_lock_irqsave(&hpb->hpb_state_lock, flags);
+	if (ufshpb_test_ppn_dirty(hpb, rgn_idx, srgn_idx, srgn_offset,
+				   transfer_len)) {
+		atomic_inc(&hpb->stats.miss_cnt);
+		spin_unlock_irqrestore(&hpb->hpb_state_lock, flags);
+		goto put_hpb;
+	}
+
+	ppn = ufshpb_get_ppn(hpb, srgn->mctx, srgn_offset, &err);
+	spin_unlock_irqrestore(&hpb->hpb_state_lock, flags);
+	if (unlikely(err)) {
+		/*
+		 * In this case, the region state is active,
+		 * but the ppn table is not allocated.
+		 * Make sure that ppn table must be allocated on
+		 * active state.
+		 */
+		WARN_ON(true);
+		dev_err(&hpb->hpb_lu_dev,
+			"ufshpb_get_ppn failed. err %d\n", err);
+		goto put_hpb;
+	}
+
+	ufshpb_set_hpb_read_to_upiu(hpb, lrbp, lpn, ppn, transfer_len);
+
+	atomic_inc(&hpb->stats.hit_cnt);
+put_hpb:
+	ufshpb_lu_put(hpb);
+}
+
 static struct ufshpb_req *ufshpb_get_map_req(struct ufshpb_lu *hpb,
 					     struct ufshpb_subregion *srgn)
 {
@@ -1671,6 +1905,7 @@ static struct ufshpb_driver ufshpb_drv = {
 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
 	},
 	.ufshpb_ops = {
+		.prep_fn = ufshpb_prep_fn,
 		.reset = ufshpb_reset,
 		.reset_host = ufshpb_reset_host,
 		.suspend = ufshpb_suspend,
-- 
2.17.1

RE: [RFC PATCH v3 4/5] scsi: ufs: L2P map management for HPB read

[Avri Altman]

>  static struct ufshpb_driver ufshpb_drv;
> +unsigned int ufshpb_host_map_kbytes = 1 * 1024;
I think you've already declared this as a module parameter in 3/5.

No need to fix this now, unless there will be some more comments,
And you'll issue a v4.

Thanks,
Avri 

RE: [RFC PATCH v3 4/5] scsi: ufs: L2P map management for HPB read

[Daejun Park]

>  static struct ufshpb_driver ufshpb_drv;
> > +unsigned int ufshpb_host_map_kbytes = 1 * 1024;
> I think you've already declared this as a module parameter in 3/5.
> 
> No need to fix this now, unless there will be some more comments,
> And you'll issue a v4.

OK, thanks!

Re: [RFC PATCH v3 0/5] scsi: ufs: Add Host Performance Booster Support

[Bean Huo]

Hi Daejun

Seems you intentionally ignored to give you comments on my suggestion.
let me provide the reason.

Before submitting your next version patch, please check your L2P
mapping HPB reqeust submission logical algorithem. I have did
performance comparison testing on 4KB, there are about 13% performance
drop. Also the hit count is lower. I don't know if this is related to
your current work queue scheduling, since you didn't add the timer for
each HPB request.

Thanks,

Bean


On Tue, 2020-06-23 at 10:02 +0900, Daejun Park wrote:
> Changelog:
> 
> v2 -> v3
> 1. Add checking input module parameter value.
> 2. Change base commit from 5.8/scsi-queue to 5.9/scsi-queue.
> 3. Cleanup for unused variables and label.
> 
> v1 -> v2
> 1. Change the full boilerplate text to SPDX style.
> 2. Adopt dynamic allocation for sub-region data structure.
> 3. Cleanup.
> 
> NAND flash memory-based storage devices use Flash Translation Layer
> (FTL)
> to translate logical addresses of I/O requests to corresponding flash
> memory addresses. Mobile storage devices typically have RAM with
> constrained size, thus lack in memory to keep the whole mapping
> table.
> Therefore, mapping tables are partially retrieved from NAND flash on
> demand, causing random-read performance degradation.
> 
> To improve random read performance, JESD220-3 (HPB v1.0) proposes HPB
> (Host Performance Booster) which uses host system memory as a cache
> for the
> FTL mapping table. By using HPB, FTL data can be read from host
> memory
> faster than from NAND flash memory. 
> 
> The current version only supports the DCM (device control mode).
> This patch consists of 4 parts to support HPB feature.
> 
> 1) UFS-feature layer
> 2) HPB probe and initialization process
> 3) READ -> HPB READ using cached map information
> 4) L2P (logical to physical) map management
> 
> The UFS-feature is an additional layer to avoid the structure in
> which the
> UFS-core driver and the UFS-feature are entangled with each other in
> a 
> single module.
> By adding the layer, UFS-features composed of various combinations
> can be
> supported. Also, even if a new feature is added, modification of the 
> UFS-core driver can be minimized.
> 
> In the HPB probe and init process, the device information of the UFS
> is
> queried. After checking supported features, the data structure for
> the HPB
> is initialized according to the device information.
> 
> A read I/O in the active sub-region where the map is cached is
> changed to
> HPB READ by the HPB module.
> 
> The HPB module manages the L2P map using information received from
> the
> device. For active sub-region, the HPB module caches through
> ufshpb_map
> request. For the in-active region, the HPB module discards the L2P
> map.
> When a write I/O occurs in an active sub-region area, associated
> dirty
> bitmap checked as dirty for preventing stale read.
> 
> HPB is shown to have a performance improvement of 58 - 67% for random
> read
> workload. [1]
> 
> This series patches are based on the 5.9/scsi-queue branch.
> 
> [1]:
> 
https://www.usenix.org/conference/hotstorage17/program/presentation/jeong
> 
> Daejun park (5):
>  scsi: ufs: Add UFS feature related parameter
>  scsi: ufs: Add UFS feature layer
>  scsi: ufs: Introduce HPB module
>  scsi: ufs: L2P map management for HPB read
>  scsi: ufs: Prepare HPB read for cached sub-region
>  
>  drivers/scsi/ufs/Kconfig      |    9 +
>  drivers/scsi/ufs/Makefile     |    3 +-
>  drivers/scsi/ufs/ufs.h        |   12 +
>  drivers/scsi/ufs/ufsfeature.c |  148 +++
>  drivers/scsi/ufs/ufsfeature.h |   69 ++
>  drivers/scsi/ufs/ufshcd.c     |   23 +-
>  drivers/scsi/ufs/ufshcd.h     |    3 +
>  drivers/scsi/ufs/ufshpb.c     | 1996
> ++++++++++++++++++++++++++++++++++++
>  drivers/scsi/ufs/ufshpb.h     |  234 +++++
>  9 files changed, 2494 insertions(+), 3 deletions(-)
>  created mode 100644 drivers/scsi/ufs/ufsfeature.c
>  created mode 100644 drivers/scsi/ufs/ufsfeature.h
>  created mode 100644 drivers/scsi/ufs/ufshpb.c
>  created mode 100644 drivers/scsi/ufs/ufshpb.h

RE: [RFC PATCH v3 0/5] scsi: ufs: Add Host Performance Booster Support

[Avri Altman]

If no-one else objects, maybe you can submit your patches as non-RFC for review?

Thanks,
Avri

> -----Original Message-----
> From: Daejun Park <daejun7.park@samsung.com>
> Sent: Tuesday, June 23, 2020 4:02 AM
> To: Avri Altman <Avri.Altman@wdc.com>; jejb@linux.ibm.com;
> martin.petersen@oracle.com; asutoshd@codeaurora.org;
> stanley.chu@mediatek.com; cang@codeaurora.org; huobean@gmail.com;
> bvanassche@acm.org; tomas.winkler@intel.com; ALIM AKHTAR
> <alim.akhtar@samsung.com>; Daejun Park <daejun7.park@samsung.com>
> Cc: linux-scsi@vger.kernel.org; linux-kernel@vger.kernel.org; Sang-yoon Oh
> <sangyoon.oh@samsung.com>; Sung-Jun Park
> <sungjun07.park@samsung.com>; yongmyung lee
> <ymhungry.lee@samsung.com>; Jinyoung CHOI <j-
> young.choi@samsung.com>; Adel Choi <adel.choi@samsung.com>; BoRam
> Shin <boram.shin@samsung.com>
> Subject: [RFC PATCH v3 0/5] scsi: ufs: Add Host Performance Booster Support
> 
> CAUTION: This email originated from outside of Western Digital. Do not click
> on links or open attachments unless you recognize the sender and know that
> the content is safe.
> 
> 
> Changelog:
> 
> v2 -> v3
> 1. Add checking input module parameter value.
> 2. Change base commit from 5.8/scsi-queue to 5.9/scsi-queue.
> 3. Cleanup for unused variables and label.
> 
> v1 -> v2
> 1. Change the full boilerplate text to SPDX style.
> 2. Adopt dynamic allocation for sub-region data structure.
> 3. Cleanup.
> 
> NAND flash memory-based storage devices use Flash Translation Layer (FTL)
> to translate logical addresses of I/O requests to corresponding flash
> memory addresses. Mobile storage devices typically have RAM with
> constrained size, thus lack in memory to keep the whole mapping table.
> Therefore, mapping tables are partially retrieved from NAND flash on
> demand, causing random-read performance degradation.
> 
> To improve random read performance, JESD220-3 (HPB v1.0) proposes HPB
> (Host Performance Booster) which uses host system memory as a cache for
> the
> FTL mapping table. By using HPB, FTL data can be read from host memory
> faster than from NAND flash memory.
> 
> The current version only supports the DCM (device control mode).
> This patch consists of 4 parts to support HPB feature.
> 
> 1) UFS-feature layer
> 2) HPB probe and initialization process
> 3) READ -> HPB READ using cached map information
> 4) L2P (logical to physical) map management
> 
> The UFS-feature is an additional layer to avoid the structure in which the
> UFS-core driver and the UFS-feature are entangled with each other in a
> single module.
> By adding the layer, UFS-features composed of various combinations can be
> supported. Also, even if a new feature is added, modification of the
> UFS-core driver can be minimized.
> 
> In the HPB probe and init process, the device information of the UFS is
> queried. After checking supported features, the data structure for the HPB
> is initialized according to the device information.
> 
> A read I/O in the active sub-region where the map is cached is changed to
> HPB READ by the HPB module.
> 
> The HPB module manages the L2P map using information received from the
> device. For active sub-region, the HPB module caches through ufshpb_map
> request. For the in-active region, the HPB module discards the L2P map.
> When a write I/O occurs in an active sub-region area, associated dirty
> bitmap checked as dirty for preventing stale read.
> 
> HPB is shown to have a performance improvement of 58 - 67% for random
> read
> workload. [1]
> 
> This series patches are based on the 5.9/scsi-queue branch.
> 
> [1]:
> https://www.usenix.org/conference/hotstorage17/program/presentation/jeo
> ng
> 
> Daejun park (5):
>  scsi: ufs: Add UFS feature related parameter
>  scsi: ufs: Add UFS feature layer
>  scsi: ufs: Introduce HPB module
>  scsi: ufs: L2P map management for HPB read
>  scsi: ufs: Prepare HPB read for cached sub-region
> 
>  drivers/scsi/ufs/Kconfig      |    9 +
>  drivers/scsi/ufs/Makefile     |    3 +-
>  drivers/scsi/ufs/ufs.h        |   12 +
>  drivers/scsi/ufs/ufsfeature.c |  148 +++
>  drivers/scsi/ufs/ufsfeature.h |   69 ++
>  drivers/scsi/ufs/ufshcd.c     |   23 +-
>  drivers/scsi/ufs/ufshcd.h     |    3 +
>  drivers/scsi/ufs/ufshpb.c     | 1996 ++++++++++++++++++++++++++++++++++++
>  drivers/scsi/ufs/ufshpb.h     |  234 +++++
>  9 files changed, 2494 insertions(+), 3 deletions(-)
>  created mode 100644 drivers/scsi/ufs/ufsfeature.c
>  created mode 100644 drivers/scsi/ufs/ufsfeature.h
>  created mode 100644 drivers/scsi/ufs/ufshpb.c
>  created mode 100644 drivers/scsi/ufs/ufshpb.h

RE: [RFC PATCH v3 0/5] scsi: ufs: Add Host Performance Booster Support

[Avri Altman]

Hi Bean,
> 
> Hi Daejun
> 
> Seems you intentionally ignored to give you comments on my suggestion.
> let me provide the reason.
> 
> Before submitting your next version patch, please check your L2P
> mapping HPB reqeust submission logical algorithem. I have did
> performance comparison testing on 4KB, there are about 13% performance
> drop. Also the hit count is lower. I don't know if this is related to
> your current work queue scheduling, since you didn't add the timer for
> each HPB request.
In device control mode, the various decisions,
and specifically those that are causing repetitive evictions,
are made by the device.
Is this the issue that you are referring to? 

As for the driver, do you see any issue that is causing unnecessary latency? 

Thanks,
Avri 

Re: [RFC PATCH v3 0/5] scsi: ufs: Add Host Performance Booster Support

[Daejun Park]

> Seems you intentionally ignored to give you comments on my suggestion.
> let me provide the reason.
Sorry! I replied to your comment (https://lkml.org/lkml/2020/6/15/1492),
but you didn't reply on that. I thought you agreed because you didn't send
any more comments.


> Before submitting your next version patch, please check your L2P
> mapping HPB reqeust submission logical algorithem. I have did
We are also reviewing the code that you submitted before.
It seems to be a performance improvement as it sends a map request directly.

> performance comparison testing on 4KB, there are about 13% performance
> drop. Also the hit count is lower. I don't know if this is related to
It is interesting that there is actually a performance improvement. 
Could you share the test environment, please? However, I think stability is
important to HPB driver. We have tested our method with the real products and
the HPB 1.0 driver is based on that.
After this patch, your approach can be done as an incremental patch? I would
like to test the patch that you submitted and verify it.

> your current work queue scheduling, since you didn't add the timer for
> each HPB request.
There was Bart's comment that it was not good add an arbitrary timeout value
to the request. (please refer to: https://lkml.org/lkml/2020/6/11/1043)
When no timer is added to the request, the SD timout will be set as default
timeout at the block layer.

Thanks,
Daejun

Re: [RFC PATCH v3 0/5] scsi: ufs: Add Host Performance Booster Support

[Bean Huo]

Hi Avri

On Mon, 2020-06-29 at 05:24 +0000, Avri Altman wrote:
> Hi Bean,
> > 
> > Hi Daejun
> > 
> > Seems you intentionally ignored to give you comments on my
> > suggestion.
> > let me provide the reason.
> > 
> > Before submitting your next version patch, please check your L2P
> > mapping HPB reqeust submission logical algorithem. I have did
> > performance comparison testing on 4KB, there are about 13%
> > performance
> > drop. Also the hit count is lower. I don't know if this is related
> > to
> > your current work queue scheduling, since you didn't add the timer
> > for
> > each HPB request.
> 
> In device control mode, the various decisions,
> and specifically those that are causing repetitive evictions,
> are made by the device.
> Is this the issue that you are referring to? 
> 

For this device mode, if HPB mapping table of the active region becomes
dirty in the UFS device side, there is repetitive inactive rsp, but it
is not the reason for the condition I mentioned here.  

> As for the driver, do you see any issue that is causing unnecessary
> latency? 
> 

In Daejun's patch, it now uses work_queue, and as long there is new RSP of thesubregion to be activated, the driver will queue "work" to this work
queue, actually, this is deferred work. we don't know when it will be
scheduled/finished. we need to optimize it.


Thanks,
Bean

RE: [RFC PATCH v3 0/5] scsi: ufs: Add Host Performance Booster Support

[Avri Altman]

> 
> Hi Avri
> 
> On Mon, 2020-06-29 at 05:24 +0000, Avri Altman wrote:
> > Hi Bean,
> > >
> > > Hi Daejun
> > >
> > > Seems you intentionally ignored to give you comments on my
> > > suggestion.
> > > let me provide the reason.
> > >
> > > Before submitting your next version patch, please check your L2P
> > > mapping HPB reqeust submission logical algorithem. I have did
> > > performance comparison testing on 4KB, there are about 13%
> > > performance
> > > drop. Also the hit count is lower. I don't know if this is related
> > > to
> > > your current work queue scheduling, since you didn't add the timer
> > > for
> > > each HPB request.
> >
> > In device control mode, the various decisions,
> > and specifically those that are causing repetitive evictions,
> > are made by the device.
> > Is this the issue that you are referring to?
> >
> 
> For this device mode, if HPB mapping table of the active region becomes
> dirty in the UFS device side, there is repetitive inactive rsp, but it
> is not the reason for the condition I mentioned here.
> 
> > As for the driver, do you see any issue that is causing unnecessary
> > latency?
> >
> 
> In Daejun's patch, it now uses work_queue, and as long there is new RSP of
> thesubregion to be activated, the driver will queue "work" to this work
> queue, actually, this is deferred work. we don't know when it will be
> scheduled/finished. we need to optimize it.
But those "to-do" lists are checked on every completion interrupt and on every resume.
Do you see any scenario in which the "to-be-activated" or "to-be-inactivate" work is getting starved?

Re: [RFC PATCH v3 0/5] scsi: ufs: Add Host Performance Booster Support

[Bean Huo]

Hi Daejun

On Mon, 2020-06-29 at 15:15 +0900, Daejun Park wrote:
> > Seems you intentionally ignored to give you comments on my
> > suggestion.
> > let me provide the reason.
> 
> Sorry! I replied to your comment (
> https://lkml.org/lkml/2020/6/15/1492),
> but you didn't reply on that. I thought you agreed because you didn't
> send
> any more comments.
> 
> 
> > Before submitting your next version patch, please check your L2P
> > mapping HPB reqeust submission logical algorithem. I have did
> 
> We are also reviewing the code that you submitted before.
> It seems to be a performance improvement as it sends a map request
> directly.
> 
> > performance comparison testing on 4KB, there are about 13%
> > performance
> > drop. Also the hit count is lower. I don't know if this is related
> > to
> 
> It is interesting that there is actually a performance improvement. 
> Could you share the test environment, please? However, I think
> stability is
> important to HPB driver. We have tested our method with the real
> products and
> the HPB 1.0 driver is based on that.

I just run fio benchmark tool with --rw=randread, --bs=4kb, --
size=8G/10G/64G/100G. and see what performance diff with the direct
submission approach.

> After this patch, your approach can be done as an incremental patch?
> I would
> like to test the patch that you submitted and verify it.
> 
> > your current work queue scheduling, since you didn't add the timer
> > for
> > each HPB request.
> 

Taking into consideration of the HPB 2.0, can we submit the HPB write
request to the SCSI layer? if not, it will be a direct submission way.
why not directly use direct way? or maybe you have a more advisable
approach to work around this. would you please share with us.
appreciate.


> There was Bart's comment that it was not good add an arbitrary
> timeout value
> to the request. (please refer to: 
> https://lkml.org/lkml/2020/6/11/1043)
> When no timer is added to the request, the SD timout will be set as
> default
> timeout at the block layer.
> 

I saw that, so I should add a timer in order to optimise HPB reqeust
scheduling/completition. this is ok so far.

> Thanks,
> Daejun

Thanks,
Bean

Re: [RFC PATCH v3 0/5] scsi: ufs: Add Host Performance Booster Support

[Bean Huo]

On Mon, 2020-06-29 at 11:06 +0000, Avri Altman wrote:
> > 
> > Hi Avri
> > 
> > On Mon, 2020-06-29 at 05:24 +0000, Avri Altman wrote:
> > > Hi Bean,
> > > > 
> > > > Hi Daejun
> > > > 
> > > > Seems you intentionally ignored to give you comments on my
> > > > suggestion.
> > > > let me provide the reason.
> > > > 
> > > > Before submitting your next version patch, please check your
> > > > L2P
> > > > mapping HPB reqeust submission logical algorithem. I have did
> > > > performance comparison testing on 4KB, there are about 13%
> > > > performance
> > > > drop. Also the hit count is lower. I don't know if this is
> > > > related
> > > > to
> > > > your current work queue scheduling, since you didn't add the
> > > > timer
> > > > for
> > > > each HPB request.
> > > 
> > > In device control mode, the various decisions,
> > > and specifically those that are causing repetitive evictions,
> > > are made by the device.
> > > Is this the issue that you are referring to?
> > > 
> > 
> > For this device mode, if HPB mapping table of the active region
> > becomes
> > dirty in the UFS device side, there is repetitive inactive rsp, but
> > it
> > is not the reason for the condition I mentioned here.
> > 
> > > As for the driver, do you see any issue that is causing
> > > unnecessary
> > > latency?
> > > 
> > 
> > In Daejun's patch, it now uses work_queue, and as long there is new
> > RSP of
> > thesubregion to be activated, the driver will queue "work" to this
> > work
> > queue, actually, this is deferred work. we don't know when it will
> > be
> > scheduled/finished. we need to optimize it.
> 
> But those "to-do" lists are checked on every completion interrupt and
> on every resume.
> Do you see any scenario in which the "to-be-activated" or "to-be-
> inactivate" work is getting starved?
> 

let me run more testing cases, will back to you if there is new
updates.

Thanks,
Bean

Re: [RFC PATCH v3 0/5] scsi: ufs: Add Host Performance Booster Support

[Daejun Park]

Hi Bean,
> On Mon, 2020-06-29 at 15:15 +0900, Daejun Park wrote:
> > > Seems you intentionally ignored to give you comments on my
> > > suggestion.
> > > let me provide the reason.
> > 
> > Sorry! I replied to your comment (
> > https://protect2.fireeye.com/url?k=be575021-e3854728-be56db6e-0cc47a31cdf8-6c7d0e1e42762b92&q=1&u=https%3A%2F%2Flkml.org%2Flkml%2F2020%2F6%2F15%2F1492),
> > but you didn't reply on that. I thought you agreed because you didn't
> > send
> > any more comments.
> > 
> > 
> > > Before submitting your next version patch, please check your L2P
> > > mapping HPB reqeust submission logical algorithem. I have did
> > 
> > We are also reviewing the code that you submitted before.
> > It seems to be a performance improvement as it sends a map request
> > directly.
> > 
> > > performance comparison testing on 4KB, there are about 13%
> > > performance
> > > drop. Also the hit count is lower. I don't know if this is related
> > > to
> > 
> > It is interesting that there is actually a performance improvement. 
> > Could you share the test environment, please? However, I think
> > stability is
> > important to HPB driver. We have tested our method with the real
> > products and
> > the HPB 1.0 driver is based on that.
> 
> I just run fio benchmark tool with --rw=randread, --bs=4kb, --
> size=8G/10G/64G/100G. and see what performance diff with the direct
> submission approach.

Thanks!

> > After this patch, your approach can be done as an incremental patch?
> > I would
> > like to test the patch that you submitted and verify it.
> > 
> > > your current work queue scheduling, since you didn't add the timer
> > > for
> > > each HPB request.
> > 
> 
> Taking into consideration of the HPB 2.0, can we submit the HPB write
> request to the SCSI layer? if not, it will be a direct submission way.
> why not directly use direct way? or maybe you have a more advisable
> approach to work around this. would you please share with us.
> appreciate.

I am considering a direct submission way for the next version.
We will implement the write buffer command of HPB 2.0, after patching HPB 1.0.

As for the direct submission of HPB releated command including HPB write
buffer, I think we'd better discuss the right approach in depth before
moving on to the next step.

Thanks,
Daejun

RE: [RFC PATCH v3 0/5] scsi: ufs: Add Host Performance Booster Support

[Avri Altman]

Hi,
 
> 
> Hi Bean,
> > On Mon, 2020-06-29 at 15:15 +0900, Daejun Park wrote:
> > > > Seems you intentionally ignored to give you comments on my
> > > > suggestion.
> > > > let me provide the reason.
> > >
> > > Sorry! I replied to your comment (
> > > https://protect2.fireeye.com/url?k=be575021-e3854728-be56db6e-
> 0cc47a31cdf8-
> 6c7d0e1e42762b92&q=1&u=https%3A%2F%2Flkml.org%2Flkml%2F2020%2F6%
> 2F15%2F1492),
> > > but you didn't reply on that. I thought you agreed because you didn't
> > > send
> > > any more comments.
> > >
> > >
> > > > Before submitting your next version patch, please check your L2P
> > > > mapping HPB reqeust submission logical algorithem. I have did
> > >
> > > We are also reviewing the code that you submitted before.
> > > It seems to be a performance improvement as it sends a map request
> > > directly.
> > >
> > > > performance comparison testing on 4KB, there are about 13%
> > > > performance
> > > > drop. Also the hit count is lower. I don't know if this is related
> > > > to
> > >
> > > It is interesting that there is actually a performance improvement.
> > > Could you share the test environment, please? However, I think
> > > stability is
> > > important to HPB driver. We have tested our method with the real
> > > products and
> > > the HPB 1.0 driver is based on that.
> >
> > I just run fio benchmark tool with --rw=randread, --bs=4kb, --
> > size=8G/10G/64G/100G. and see what performance diff with the direct
> > submission approach.
> 
> Thanks!
> 
> > > After this patch, your approach can be done as an incremental patch?
> > > I would
> > > like to test the patch that you submitted and verify it.
> > >
> > > > your current work queue scheduling, since you didn't add the timer
> > > > for
> > > > each HPB request.
> > >
> >
> > Taking into consideration of the HPB 2.0, can we submit the HPB write
> > request to the SCSI layer? if not, it will be a direct submission way.
> > why not directly use direct way? or maybe you have a more advisable
> > approach to work around this. would you please share with us.
> > appreciate.
> 
> I am considering a direct submission way for the next version.
> We will implement the write buffer command of HPB 2.0, after patching HPB
> 1.0.
> 
> As for the direct submission of HPB releated command including HPB write
> buffer, I think we'd better discuss the right approach in depth before
> moving on to the next step.
I vote to stay with the current implementation because:
1) Bean is probably right about 2.0, but it's out of scope for now - 
    there is a long way to go before we'll need to worry about it
2) For now, we should focus on the functional flows. 
    Performance issues, should such issues indeed exists, can be dealt with  later.  And,
3) The current code base is running in production for more than 3 years now.
     I am not so eager to dump a robust, well debugged code unless it absolutely necessary.

Thanks,
Avri

Re: [RFC PATCH v3 0/5] scsi: ufs: Add Host Performance Booster Support

[Bean Huo]

On Tue, 2020-06-30 at 06:39 +0000, Avri Altman wrote:
> Hi,
>  
> > 
> > Hi Bean,
> > > On Mon, 2020-06-29 at 15:15 +0900, Daejun Park wrote:
> > > > > Seems you intentionally ignored to give you comments on my
> > > > > suggestion.
> > > > > let me provide the reason.
> > > > 
> > > > Sorry! I replied to your comment (
> > > > https://protect2.fireeye.com/url?k=be575021-e3854728-be56db6e-
> > 
> > 0cc47a31cdf8-
> > 6c7d0e1e42762b92&q=1&u=https%3A%2F%2Flkml.org%2Flkml%2F2020%2F6%
> > 2F15%2F1492),
> > > > but you didn't reply on that. I thought you agreed because you
> > > > didn't
> > > > send
> > > > any more comments.
> > > > 
> > > > 
> > > > > Before submitting your next version patch, please check your
> > > > > L2P
> > > > > mapping HPB reqeust submission logical algorithem. I have did
> > > > 
> > > > We are also reviewing the code that you submitted before.
> > > > It seems to be a performance improvement as it sends a map
> > > > request
> > > > directly.
> > > > 
> > > > > performance comparison testing on 4KB, there are about 13%
> > > > > performance
> > > > > drop. Also the hit count is lower. I don't know if this is
> > > > > related
> > > > > to
> > > > 
> > > > It is interesting that there is actually a performance
> > > > improvement.
> > > > Could you share the test environment, please? However, I think
> > > > stability is
> > > > important to HPB driver. We have tested our method with the
> > > > real
> > > > products and
> > > > the HPB 1.0 driver is based on that.
> > > 
> > > I just run fio benchmark tool with --rw=randread, --bs=4kb, --
> > > size=8G/10G/64G/100G. and see what performance diff with the
> > > direct
> > > submission approach.
> > 
> > Thanks!
> > 
> > > > After this patch, your approach can be done as an incremental
> > > > patch?
> > > > I would
> > > > like to test the patch that you submitted and verify it.
> > > > 
> > > > > your current work queue scheduling, since you didn't add the
> > > > > timer
> > > > > for
> > > > > each HPB request.
> > > 
> > > Taking into consideration of the HPB 2.0, can we submit the HPB
> > > write
> > > request to the SCSI layer? if not, it will be a direct submission
> > > way.
> > > why not directly use direct way? or maybe you have a more
> > > advisable
> > > approach to work around this. would you please share with us.
> > > appreciate.
> > 
> > I am considering a direct submission way for the next version.
> > We will implement the write buffer command of HPB 2.0, after
> > patching HPB
> > 1.0.
> > 
> > As for the direct submission of HPB releated command including HPB
> > write
> > buffer, I think we'd better discuss the right approach in depth
> > before
> > moving on to the next step.
> 
> I vote to stay with the current implementation because:
> 1) Bean is probably right about 2.0, but it's out of scope for now - 
>     there is a long way to go before we'll need to worry about it
> 2) For now, we should focus on the functional flows. 
>     Performance issues, should such issues indeed exists, can be
> dealt with  later.  And,
> 3) The current code base is running in production for more than 3
> years now.
>      I am not so eager to dump a robust, well debugged code unless it
> absolutely necessary.
> 
> Thanks,
> Avri
> 
> 
Hi Avri
Thanks, appreciate you shared your position on this topic. I don't know
how I can convince you to change your opinion.
Let me try.

1. HPB 2.0 is not out of scope.
HPB 1.0 only supports 4KB read length, which is useless. I don't know
if there will be users who want to use HPB driver only supports 4KB
chunk size. I think, we all know that some smartphone vendors have
already use HPB 2.0, even HPB 2.0 has not been released yet. you
mentioned this in your before emails. HPB 1.0 is just a
transition(limited) version, we need to think about the HPB 2.0 support
when we develop the HPB 1.0 driver.
To say the least, if we don't think about HPB 2.0 support, and just
focus HPB 1.0, in the end, after HPB 2.0 releasing, we need to return
original point, re-do lots thing, why we cannot fix it now and think
one step further.

2. The major goal of the HPB feature is to improve random read
performance, and HPB device mode implementing flow is now already very
clear enough. I don't know what the functional flows you mentioned.
if it is HPB host mode, no, this is another big topic, I think we'd
better not add in current driver until we all have a final approach.

3. Regarding the Daejun's HPB driver used age, I can't easily jump to a
conclusion. But for sure, before he disclosed his HPB driver and
submitted to the community, he did lots of changes and deletions. That
means it still needs lots of tests.


I didn't mean to disrupt Daejun's patch upstreaming. If Daejun can
consider HPB 2.0 support while developing HPB 1.0 patch, that is super.
Thus we can quickly add HPB 2.0 support once HPB 2.0 Spec released.
Think about that who is now using HPB 1.0?

Thanks,
Bean




 

Re: [RFC PATCH v3 0/5] scsi: ufs: Add Host Performance Booster Support

[Bean Huo]

On Tue, 2020-06-30 at 10:05 +0900, Daejun Park wrote:
> Hi Bean,
> > On Mon, 2020-06-29 at 15:15 +0900, Daejun Park wrote:
> > > > Seems you intentionally ignored to give you comments on my
> > > > suggestion.
> > > > let me provide the reason.
> > > 
> > > Sorry! I replied to your comment (
> > > 
https://protect2.fireeye.com/url?k=be575021-e3854728-be56db6e-0cc47a31cdf8-6c7d0e1e42762b92&q=1&u=https%3A%2F%2Flkml.org%2Flkml%2F2020%2F6%2F15%2F1492
> > > ),
> > > but you didn't reply on that. I thought you agreed because you
> > > didn't
> > > send
> > > any more comments.
> > > 
> > > 
> > > > Before submitting your next version patch, please check your
> > > > L2P
> > > > mapping HPB reqeust submission logical algorithem. I have did
> > > 
> > > We are also reviewing the code that you submitted before.
> > > It seems to be a performance improvement as it sends a map
> > > request
> > > directly.
> > > 
> > > > performance comparison testing on 4KB, there are about 13%
> > > > performance
> > > > drop. Also the hit count is lower. I don't know if this is
> > > > related
> > > > to
> > > 
> > > It is interesting that there is actually a performance
> > > improvement. 
> > > Could you share the test environment, please? However, I think
> > > stability is
> > > important to HPB driver. We have tested our method with the real
> > > products and
> > > the HPB 1.0 driver is based on that.
> > 
> > I just run fio benchmark tool with --rw=randread, --bs=4kb, --
> > size=8G/10G/64G/100G. and see what performance diff with the direct
> > submission approach.
> 
> Thanks!
> 
> > > After this patch, your approach can be done as an incremental
> > > patch?
> > > I would
> > > like to test the patch that you submitted and verify it.
> > > 
> > > > your current work queue scheduling, since you didn't add the
> > > > timer
> > > > for
> > > > each HPB request.
> > 
> > Taking into consideration of the HPB 2.0, can we submit the HPB
> > write
> > request to the SCSI layer? if not, it will be a direct submission
> > way.
> > why not directly use direct way? or maybe you have a more advisable
> > approach to work around this. would you please share with us.
> > appreciate.
> 
> I am considering a direct submission way for the next version.
> We will implement the write buffer command of HPB 2.0, after patching
> HPB 1.0.
> 
> As for the direct submission of HPB releated command including HPB
> write
> buffer, I think we'd better discuss the right approach in depth
> before
> moving on to the next step.
> 

Hi Daejun
If you need reference code, you can freely copy my code from my RFC v3
patchset. or if you need my side testing support, just let me, I can
help you test your code.

Thanks,
Bean

Re: [RFC PATCH v3 0/5] scsi: ufs: Add Host Performance Booster Support

[Daejun Park]

On Tue, 2020-06-30 at 10:05 +0900, Daejun Park wrote:
> > Hi Bean,
> > > On Mon, 2020-06-29 at 15:15 +0900, Daejun Park wrote:
> > > > > Seems you intentionally ignored to give you comments on my
> > > > > suggestion.
> > > > > let me provide the reason.
> > > > 
> > > > Sorry! I replied to your comment (
> > > > 
> https://protect2.fireeye.com/url?k=be575021-e3854728-be56db6e-0cc47a31cdf8-6c7d0e1e42762b92&q=1&u=https%3A%2F%2Flkml.org%2Flkml%2F2020%2F6%2F15%2F1492
> > > > ),
> > > > but you didn't reply on that. I thought you agreed because you
> > > > didn't
> > > > send
> > > > any more comments.
> > > > 
> > > > 
> > > > > Before submitting your next version patch, please check your
> > > > > L2P
> > > > > mapping HPB reqeust submission logical algorithem. I have did
> > > > 
> > > > We are also reviewing the code that you submitted before.
> > > > It seems to be a performance improvement as it sends a map
> > > > request
> > > > directly.
> > > > 
> > > > > performance comparison testing on 4KB, there are about 13%
> > > > > performance
> > > > > drop. Also the hit count is lower. I don't know if this is
> > > > > related
> > > > > to
> > > > 
> > > > It is interesting that there is actually a performance
> > > > improvement. 
> > > > Could you share the test environment, please? However, I think
> > > > stability is
> > > > important to HPB driver. We have tested our method with the real
> > > > products and
> > > > the HPB 1.0 driver is based on that.
> > > 
> > > I just run fio benchmark tool with --rw=randread, --bs=4kb, --
> > > size=8G/10G/64G/100G. and see what performance diff with the direct
> > > submission approach.
> > 
> > Thanks!
> > 
> > > > After this patch, your approach can be done as an incremental
> > > > patch?
> > > > I would
> > > > like to test the patch that you submitted and verify it.
> > > > 
> > > > > your current work queue scheduling, since you didn't add the
> > > > > timer
> > > > > for
> > > > > each HPB request.
> > > 
> > > Taking into consideration of the HPB 2.0, can we submit the HPB
> > > write
> > > request to the SCSI layer? if not, it will be a direct submission
> > > way.
> > > why not directly use direct way? or maybe you have a more advisable
> > > approach to work around this. would you please share with us.
> > > appreciate.
> > 
> > I am considering a direct submission way for the next version.
> > We will implement the write buffer command of HPB 2.0, after patching
> > HPB 1.0.
> > 
> > As for the direct submission of HPB releated command including HPB
> > write
> > buffer, I think we'd better discuss the right approach in depth
> > before
> > moving on to the next step.
> > 
> 
> Hi Daejun
> If you need reference code, you can freely copy my code from my RFC v3
> patchset. or if you need my side testing support, just let me, I can
> help you test your code.
> 
It will be good example code for developing HPB 2.0.

Thanks,
Daejun

RE: [RFC PATCH v3 0/5] scsi: ufs: Add Host Performance Booster Support

[Alim Akhtar]

> -----Original Message-----
> From: Avri Altman <Avri.Altman@wdc.com>
> Sent: 30 June 2020 12:09
> To: daejun7.park@samsung.com; Bean Huo <huobean@gmail.com>;
> jejb@linux.ibm.com; martin.petersen@oracle.com; asutoshd@codeaurora.org;
> stanley.chu@mediatek.com; cang@codeaurora.org; bvanassche@acm.org;
> tomas.winkler@intel.com; ALIM AKHTAR <alim.akhtar@samsung.com>
> Cc: linux-scsi@vger.kernel.org; linux-kernel@vger.kernel.org; Sang-yoon Oh
> <sangyoon.oh@samsung.com>; Sung-Jun Park
> <sungjun07.park@samsung.com>; yongmyung lee
> <ymhungry.lee@samsung.com>; Jinyoung CHOI <j-young.choi@samsung.com>;
> Adel Choi <adel.choi@samsung.com>; BoRam Shin
> <boram.shin@samsung.com>
> Subject: RE: [RFC PATCH v3 0/5] scsi: ufs: Add Host Performance Booster
> Support
> 
> Hi,
> 
> >
> > Hi Bean,
> > > On Mon, 2020-06-29 at 15:15 +0900, Daejun Park wrote:
> > > > > Seems you intentionally ignored to give you comments on my
> > > > > suggestion.
> > > > > let me provide the reason.
> > > >
> > > > Sorry! I replied to your comment (
> > > > https://protect2.fireeye.com/url?k=be575021-e3854728-be56db6e-
> > 0cc47a31cdf8-
> >
> 6c7d0e1e42762b92&q=1&u=https%3A%2F%2Flkml.org%2Flkml%2F2020%2F6%
> > 2F15%2F1492),
> > > > but you didn't reply on that. I thought you agreed because you
> > > > didn't send any more comments.
> > > >
> > > >
> > > > > Before submitting your next version patch, please check your L2P
> > > > > mapping HPB reqeust submission logical algorithem. I have did
> > > >
> > > > We are also reviewing the code that you submitted before.
> > > > It seems to be a performance improvement as it sends a map request
> > > > directly.
> > > >
> > > > > performance comparison testing on 4KB, there are about 13%
> > > > > performance drop. Also the hit count is lower. I don't know if
> > > > > this is related to
> > > >
> > > > It is interesting that there is actually a performance improvement.
> > > > Could you share the test environment, please? However, I think
> > > > stability is important to HPB driver. We have tested our method
> > > > with the real products and the HPB 1.0 driver is based on that.
> > >
> > > I just run fio benchmark tool with --rw=randread, --bs=4kb, --
> > > size=8G/10G/64G/100G. and see what performance diff with the direct
> > > submission approach.
> >
> > Thanks!
> >
> > > > After this patch, your approach can be done as an incremental patch?
> > > > I would
> > > > like to test the patch that you submitted and verify it.
> > > >
> > > > > your current work queue scheduling, since you didn't add the
> > > > > timer for each HPB request.
> > > >
> > >
> > > Taking into consideration of the HPB 2.0, can we submit the HPB
> > > write request to the SCSI layer? if not, it will be a direct submission way.
> > > why not directly use direct way? or maybe you have a more advisable
> > > approach to work around this. would you please share with us.
> > > appreciate.
> >
> > I am considering a direct submission way for the next version.
> > We will implement the write buffer command of HPB 2.0, after patching
> > HPB 1.0.
> >
> > As for the direct submission of HPB releated command including HPB
> > write buffer, I think we'd better discuss the right approach in depth
> > before moving on to the next step.
> I vote to stay with the current implementation because:
> 1) Bean is probably right about 2.0, but it's out of scope for now -
>     there is a long way to go before we'll need to worry about it
> 2) For now, we should focus on the functional flows.
>     Performance issues, should such issues indeed exists, can be dealt with  later.
> And,
> 3) The current code base is running in production for more than 3 years now.
>      I am not so eager to dump a robust, well debugged code unless it absolutely
> necessary.
> 
Avri and Bean,
I think this is good approach to take, and let us add incremental patches to add future specification enhancements.
 
> Thanks,
> Avri
>