[PATCH v9 0/4] scsi: ufs: Add Host Performance Booster Support

[PATCH v9 0/4] scsi: ufs: Add Host Performance Booster Support

[Daejun Park]

Changelog:

v8 -> v9
1. Change sysfs initialization.
2. Change reading descriptor during HPB initialization
3. Fix problems commentted in Bart's review.
4. Change base commit from 5.9/scsi-queue to 5.10/scsi-queue.

v7 -> v8
Remove wrongly added tags.

v6 -> v7
1. Remove UFS feature layer.
2. Cleanup for sparse error.

v5 -> v6
Change base commit to b53293fa662e28ae0cdd40828dc641c09f133405

v4 -> v5
Delete unused macro define.

v3 -> v4
1. Cleanup.

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 3 parts to support HPB feature.

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

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.

The HPB manages the L2P map using information received from the
device. For active sub-region, the HPB caches through ufshpb_map
request. For the in-active region, the HPB 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 (4):
 scsi: ufs: Add HPB feature related parameters
 scsi: ufs: Introduce HPB feature
 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 |    1 +
 drivers/scsi/ufs/ufs.h    |   47 ++
 drivers/scsi/ufs/ufshcd.c |   58 ++
 drivers/scsi/ufs/ufshcd.h |   22 +-
 drivers/scsi/ufs/ufshpb.c | 1817 ++++++++++++++++++++++++++++++++++++++++
 drivers/scsi/ufs/ufshpb.h |  231 +++++
 7 files changed, 2184 insertions(+), 1 deletion(-)
 created mode 100644 drivers/scsi/ufs/ufshpb.c
 created mode 100644 drivers/scsi/ufs/ufshpb.h

[PATCH v9 1/4] scsi: ufs: Add HPB feature related parameters

[Daejun Park]

This is a patch for parameters to be used for HPB feature.

Acked-by: Avri Altman <Avri.Altman@wdc.com>
Reviewed-by: Can Guo <cang@codeaurora.org>
Tested-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Daejun Park <daejun7.park@samsung.com>
---
 drivers/scsi/ufs/ufs.h | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h
index f8ab16f30fdc..e879ac34c065 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_PARAM_HPB_REGION_SIZE	= 0x48,
+	GEOMETRY_DESC_PARAM_HPB_NUMBER_LU	= 0x49,
+	GEOMETRY_DESC_PARAM_HPB_SUBREGION_SIZE	= 0x4A,
+	GEOMETRY_DESC_PARAM_HPB_MAX_ACTIVE_REGS	= 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,
@@ -327,8 +337,10 @@ enum {
 
 /* Possible values for dExtendedUFSFeaturesSupport */
 enum {
+	UFS_DEV_HPB_SUPPORT		= BIT(7),
 	UFS_DEV_WRITE_BOOSTER_SUP	= BIT(8),
 };
+#define UFS_DEV_HPB_SUPPORT_VERSION		0x310
 
 #define POWER_DESC_MAX_SIZE			0x62
 #define POWER_DESC_MAX_ACTV_ICC_LVLS		16
@@ -537,6 +549,7 @@ 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;
-- 
2.17.1

[PATCH v9 2/4] scsi: ufs: Introduce HPB feature

[Daejun Park]

This is a patch for the HPB feature.
This patch adds HPB function calls to UFS core driver.

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

To gurantee a minimum memory pool size of 4MB: ufshpb_host_map_kbytes=4096

Acked-by: Avri Altman <Avri.Altman@wdc.com>
Tested-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Daejun Park <daejun7.park@samsung.com>
---
 drivers/scsi/ufs/Kconfig  |   9 +
 drivers/scsi/ufs/Makefile |   1 +
 drivers/scsi/ufs/ufshcd.c |  58 ++++
 drivers/scsi/ufs/ufshcd.h |  22 +-
 drivers/scsi/ufs/ufshpb.c | 596 ++++++++++++++++++++++++++++++++++++++
 drivers/scsi/ufs/ufshpb.h | 176 +++++++++++
 6 files changed, 861 insertions(+), 1 deletion(-)
 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 f6394999b98c..773fd241ac84 100644
--- a/drivers/scsi/ufs/Kconfig
+++ b/drivers/scsi/ufs/Kconfig
@@ -182,3 +182,12 @@ config SCSI_UFS_CRYPTO
 	  Enabling this makes it possible for the kernel to use the crypto
 	  capabilities of the UFS device (if present) to perform crypto
 	  operations on data being transferred to/from the device.
+
+config SCSI_UFS_HPB
+	bool "Support UFS Host Performance Booster"
+	depends on SCSI_UFSHCD
+	help
+	  The UFS HPB feature improves random read performance. It caches
+	  L2P (logical to physical) map of UFS to host DRAM. The driver uses HPB
+	  read command by piggybacking physical page number for bypassing FTL (flash
+	  translation layer)'s L2P address translation.
\ No newline at end of file
diff --git a/drivers/scsi/ufs/Makefile b/drivers/scsi/ufs/Makefile
index 4679af1b564e..663e17cee359 100644
--- a/drivers/scsi/ufs/Makefile
+++ b/drivers/scsi/ufs/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_SCSI_UFSHCD) += ufshcd-core.o
 ufshcd-core-y				+= ufshcd.o ufs-sysfs.o
 ufshcd-core-$(CONFIG_SCSI_UFS_BSG)	+= ufs_bsg.o
 ufshcd-core-$(CONFIG_SCSI_UFS_CRYPTO) += ufshcd-crypto.o
+ufshcd-core-$(CONFIG_SCSI_UFS_HPB) += 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 06e2439d523c..0d7af96588e2 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -22,6 +22,7 @@
 #include "ufs-sysfs.h"
 #include "ufs_bsg.h"
 #include "ufshcd-crypto.h"
+#include "ufshpb.h"
 #include <asm/unaligned.h>
 #include <linux/blkdev.h>
 
@@ -2546,6 +2547,8 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
 
 	ufshcd_comp_scsi_upiu(hba, lrbp);
 
+	ufshpb_prep(hba, lrbp);
+
 	err = ufshcd_map_sg(hba, lrbp);
 	if (err) {
 		lrbp->cmd = NULL;
@@ -4691,6 +4694,33 @@ static int ufshcd_change_queue_depth(struct scsi_device *sdev, int depth)
 	return scsi_change_queue_depth(sdev, depth);
 }
 
+static void ufshcd_hpb_destroy(struct ufs_hba *hba, struct scsi_device *sdev)
+{
+	/* skip well-known LU */
+	if (sdev->lun >= UFS_UPIU_MAX_UNIT_NUM_ID)
+		return;
+
+	if (!ufshpb_is_allowed(hba))
+		return;
+
+	ufshpb_destroy_lu(hba, sdev);
+}
+
+static void ufshcd_hpb_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;
+
+	if (!ufshpb_is_allowed(hba))
+		return;
+
+	ufshpb_init_hpb_lu(hba, sdev);
+}
+
 /**
  * ufshcd_slave_configure - adjust SCSI device configurations
  * @sdev: pointer to SCSI device
@@ -4700,6 +4730,8 @@ static int ufshcd_slave_configure(struct scsi_device *sdev)
 	struct ufs_hba *hba = shost_priv(sdev->host);
 	struct request_queue *q = sdev->request_queue;
 
+	ufshcd_hpb_configure(hba, sdev);
+
 	blk_queue_update_dma_pad(q, PRDT_DATA_BYTE_COUNT_PAD - 1);
 
 	if (ufshcd_is_rpm_autosuspend_allowed(hba))
@@ -4719,6 +4751,9 @@ static void ufshcd_slave_destroy(struct scsi_device *sdev)
 	struct ufs_hba *hba;
 
 	hba = shost_priv(sdev->host);
+
+	ufshcd_hpb_destroy(hba, sdev);
+
 	/* Drop the reference as it won't be needed anymore */
 	if (ufshcd_scsi_to_upiu_lun(sdev->lun) == UFS_UPIU_UFS_DEVICE_WLUN) {
 		unsigned long flags;
@@ -4828,6 +4863,9 @@ ufshcd_transfer_rsp_status(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
 				 */
 				pm_runtime_get_noresume(hba->dev);
 			}
+
+			if (scsi_status == SAM_STAT_GOOD)
+				ufshpb_rsp_upiu(hba, lrbp);
 			break;
 		case UPIU_TRANSACTION_REJECT_UPIU:
 			/* TODO: handle Reject UPIU Response */
@@ -6681,6 +6719,8 @@ static int ufshcd_host_reset_and_restore(struct ufs_hba *hba)
 	 * Stop the host controller and complete the requests
 	 * cleared by h/w
 	 */
+	ufshpb_reset_host(hba);
+
 	ufshcd_hba_stop(hba);
 
 	spin_lock_irqsave(hba->host->host_lock, flags);
@@ -7116,9 +7156,14 @@ 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];
 
+	if (dev_info->wspecversion >= UFS_DEV_HPB_SUPPORT_VERSION &&
+	    (dev_info->b_ufs_feature_sup & UFS_DEV_HPB_SUPPORT))
+		ufshpb_get_dev_info(hba, desc_buf);
+
 	err = ufshcd_read_string_desc(hba, model_index,
 				      &dev_info->model, SD_ASCII_STD);
 	if (err < 0) {
@@ -7347,6 +7392,10 @@ static int ufshcd_device_geo_params_init(struct ufs_hba *hba)
 	else if (desc_buf[GEOMETRY_DESC_PARAM_MAX_NUM_LUN] == 0)
 		hba->dev_info.max_lu_supported = 8;
 
+	if (hba->desc_size[QUERY_DESC_IDN_GEOMETRY] >=
+		GEOMETRY_DESC_PARAM_HPB_MAX_ACTIVE_REGS)
+		ufshpb_get_geo_info(hba, desc_buf);
+
 out:
 	kfree(desc_buf);
 	return err;
@@ -7486,6 +7535,7 @@ static int ufshcd_add_lus(struct ufs_hba *hba)
 	}
 
 	ufs_bsg_probe(hba);
+	ufshpb_init(hba);
 	scsi_scan_host(hba->host);
 	pm_runtime_put_sync(hba->dev);
 
@@ -7572,6 +7622,7 @@ static int ufshcd_probe_hba(struct ufs_hba *hba, bool async)
 	/* Enable Auto-Hibernate if configured */
 	ufshcd_auto_hibern8_enable(hba);
 
+	ufshpb_reset(hba);
 out:
 	spin_lock_irqsave(hba->host->host_lock, flags);
 	if (ret)
@@ -7618,6 +7669,7 @@ static void ufshcd_async_scan(void *data, async_cookie_t cookie)
 static const struct attribute_group *ufshcd_driver_groups[] = {
 	&ufs_sysfs_unit_descriptor_group,
 	&ufs_sysfs_lun_attributes_group,
+	&ufs_sysfs_hpb_stat_group,
 	NULL,
 };
 
@@ -8341,6 +8393,8 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 		req_link_state = UIC_LINK_OFF_STATE;
 	}
 
+	ufshpb_suspend(hba);
+
 	/*
 	 * If we can't transition into any of the low power modes
 	 * just gate the clocks.
@@ -8465,6 +8519,7 @@ 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);
+	ufshpb_resume(hba);
 out:
 	if (hba->dev_info.b_rpm_dev_flush_capable) {
 		schedule_delayed_work(&hba->rpm_dev_flush_recheck_work,
@@ -8564,6 +8619,8 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 	/* Enable Auto-Hibernate if configured */
 	ufshcd_auto_hibern8_enable(hba);
 
+	ufshpb_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);
@@ -8793,6 +8850,7 @@ EXPORT_SYMBOL(ufshcd_shutdown);
 void ufshcd_remove(struct ufs_hba *hba)
 {
 	ufs_bsg_remove(hba);
+	ufshpb_remove(hba);
 	ufs_sysfs_remove_nodes(hba->dev);
 	blk_cleanup_queue(hba->tmf_queue);
 	blk_mq_free_tag_set(&hba->tmf_tag_set);
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 618b253e5ec8..df30622a2b67 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -588,6 +588,24 @@ struct ufs_hba_variant_params {
 	u16 hba_enable_delay_us;
 	u32 wb_flush_threshold;
 };
+#ifdef CONFIG_SCSI_UFS_HPB
+/**
+ * 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
+ * @slave_conf_cnt: counter to check all lu finished initialization
+ * @hpb_disabled: flag to check if HPB is disabled
+ */
+struct ufshpb_dev_info {
+	int num_lu;
+	int rgn_size;
+	int srgn_size;
+	atomic_t slave_conf_cnt;
+	bool hpb_disabled;
+};
+#endif
 
 /**
  * struct ufs_hba - per adapter private structure
@@ -770,7 +788,9 @@ struct ufs_hba {
 	bool wb_buf_flush_enabled;
 	bool wb_enabled;
 	struct delayed_work rpm_dev_flush_recheck_work;
-
+#ifdef CONFIG_SCSI_UFS_HPB
+	struct ufshpb_dev_info ufshpb_dev;
+#endif
 #ifdef CONFIG_SCSI_UFS_CRYPTO
 	union ufs_crypto_capabilities crypto_capabilities;
 	union ufs_crypto_cap_entry *crypto_cap_array;
diff --git a/drivers/scsi/ufs/ufshpb.c b/drivers/scsi/ufs/ufshpb.c
new file mode 100644
index 000000000000..7ed1868c396b
--- /dev/null
+++ b/drivers/scsi/ufs/ufshpb.c
@@ -0,0 +1,596 @@
+// 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 <linux/async.h>
+
+#include "ufshcd.h"
+#include "ufshpb.h"
+#include "../sd.h"
+
+/* HPB enabled lu list */
+static LIST_HEAD(lh_hpb_lu);
+
+bool ufshpb_is_allowed(struct ufs_hba *hba)
+{
+	return !(hba->ufshpb_dev.hpb_disabled);
+}
+
+static int ufshpb_get_state(struct ufshpb_lu *hpb)
+{
+	return atomic_read(&hpb->hpb_state);
+}
+
+static void ufshpb_set_state(struct ufshpb_lu *hpb, int state)
+{
+	atomic_set(&hpb->hpb_state, state);
+}
+
+void ufshpb_prep(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
+{
+}
+
+void ufshpb_rsp_upiu(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
+{
+}
+
+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 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);
+}
+
+/* SYSFS functions */
+#define ufshpb_sysfs_attr_show_func(__name)				\
+static ssize_t __name##_show(struct device *dev,			\
+	struct device_attribute *attr, char *buf)			\
+{									\
+	struct scsi_device *sdev = to_scsi_device(dev);			\
+	struct ufshpb_lu *hpb = sdev->hostdata;				\
+	if (!hpb)							\
+		return -ENOENT;						\
+	return snprintf(buf, PAGE_SIZE, "%d\n",				\
+			atomic_read(&hpb->stats.__name));		\
+}									\
+static DEVICE_ATTR_RO(__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 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,
+};
+
+struct attribute_group ufs_sysfs_hpb_stat_group = {
+	.name = "hpb_sysfs",
+	.attrs = hpb_dev_attrs,
+};
+
+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);
+}
+
+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);
+
+	ufshpb_stat_init(hpb);
+
+	return 0;
+}
+
+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->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_issue_hpb_reset_query(struct ufs_hba *hba)
+{
+	int err = 0;
+	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
+			return;
+	}
+
+	if (err)
+		dev_err(hba->dev,
+			"%s setting fHpbReset flag failed with error %d\n",
+			__func__, err);
+}
+
+static void ufshpb_check_hpb_reset_query(struct ufs_hba *hba)
+{
+	int err = 0;
+	bool flag_res = true;
+	int try;
+
+	/* wait for the device to complete HPB reset query */
+	for (try = 0; try < HPB_RESET_REQ_RETRIES; try++) {
+		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);
+
+		if (err) {
+			dev_err(hba->dev,
+				"%s reading fHpbReset flag failed with error %d\n",
+				__func__, err);
+			return;
+		}
+
+		usleep_range(1000, 1100);
+
+		if (!flag_res)
+			return;
+	}
+	if (flag_res) {
+		dev_err(hba->dev,
+			"%s fHpbReset was not cleared by the device\n",
+			__func__);
+	}
+}
+
+void ufshpb_reset(struct ufs_hba *hba)
+{
+	struct ufshpb_lu *hpb;
+
+	list_for_each_entry(hpb, &lh_hpb_lu, list_hpb_lu) {
+		if (ufshpb_get_state(hpb) != HPB_RESET)
+			continue;
+		ufshpb_set_state(hpb, HPB_PRESENT);
+	}
+}
+
+void ufshpb_reset_host(struct ufs_hba *hba)
+{
+	struct ufshpb_lu *hpb;
+
+	dev_info(hba->dev, "ufshpb run reset_host");
+	list_for_each_entry(hpb, &lh_hpb_lu, list_hpb_lu) {
+		if (ufshpb_get_state(hpb) != HPB_PRESENT)
+			continue;
+		ufshpb_set_state(hpb, HPB_RESET);
+	}
+}
+
+void ufshpb_suspend(struct ufs_hba *hba)
+{
+	struct ufshpb_lu *hpb;
+
+	dev_info(hba->dev, "ufshpb goto suspend");
+
+	list_for_each_entry(hpb, &lh_hpb_lu, list_hpb_lu) {
+		if (ufshpb_get_state(hpb) != HPB_PRESENT)
+			continue;
+		ufshpb_set_state(hpb, HPB_SUSPEND);
+	}
+}
+
+void ufshpb_resume(struct ufs_hba *hba)
+{
+	struct ufshpb_lu *hpb;
+
+	dev_info(hba->dev, "ufshpb resume");
+
+	list_for_each_entry(hpb, &lh_hpb_lu, list_hpb_lu) {
+		if ((ufshpb_get_state(hpb) != HPB_PRESENT) &&
+		    (ufshpb_get_state(hpb) != HPB_SUSPEND))
+			continue;
+		ufshpb_set_state(hpb, HPB_PRESENT);
+	}
+}
+
+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_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_hpb_lu_prepared(struct ufs_hba *hba)
+{
+	struct ufshpb_lu *hpb;
+
+	if (list_empty(&lh_hpb_lu))
+		return;
+
+	ufshpb_check_hpb_reset_query(hba);
+
+	list_for_each_entry(hpb, &lh_hpb_lu, list_hpb_lu) {
+		dev_info(hba->dev, "set state to present\n");
+		ufshpb_set_state(hpb, HPB_PRESENT);
+	}
+}
+
+void ufshpb_init_hpb_lu(struct ufs_hba *hba, struct scsi_device *sdev)
+{
+	struct ufshpb_lu *hpb;
+	int ret;
+	struct ufshpb_lu_info hpb_lu_info = { 0 };
+	int lun = sdev->lun;
+	char *desc_buf;
+
+	desc_buf = kzalloc(QUERY_DESC_MAX_SIZE, GFP_KERNEL);
+	if (!desc_buf)
+		return;
+
+	if (lun >= hba->dev_info.max_lu_supported)
+		goto release_desc_buf;
+
+	ret = ufshpb_get_lu_info(hba, lun, &hpb_lu_info, desc_buf);
+	if (ret)
+		goto release_desc_buf;
+
+	hpb = ufshpb_alloc_hpb_lu(hba, lun, &hba->ufshpb_dev,
+				  &hpb_lu_info);
+	if (!hpb)
+		goto release_desc_buf;
+
+	hpb->sdev_ufs_lu = sdev;
+	sdev->hostdata = hpb;
+
+	list_add_tail(&hpb->list_hpb_lu, &lh_hpb_lu);
+
+release_desc_buf:
+	kfree(desc_buf);
+
+	/* All LUs are initialized */
+	if (atomic_dec_and_test(&hba->ufshpb_dev.slave_conf_cnt))
+		ufshpb_hpb_lu_prepared(hba);
+}
+
+void ufshpb_get_geo_info(struct ufs_hba *hba, u8 *geo_buf)
+{
+	struct ufshpb_dev_info *hpb_dev_info = &hba->ufshpb_dev;
+	int hpb_device_max_active_rgns = 0;
+	int hpb_num_lu;
+
+	hpb_dev_info->hpb_disabled = false;
+
+	hpb_num_lu = geo_buf[GEOMETRY_DESC_PARAM_HPB_NUMBER_LU];
+	if (hpb_num_lu == 0) {
+		dev_err(hba->dev, "No HPB LU supported\n");
+		hpb_dev_info->hpb_disabled = true;
+		return;
+	}
+
+	hpb_dev_info->rgn_size = geo_buf[GEOMETRY_DESC_PARAM_HPB_REGION_SIZE];
+	hpb_dev_info->srgn_size = geo_buf[GEOMETRY_DESC_PARAM_HPB_SUBREGION_SIZE];
+	hpb_device_max_active_rgns =
+		get_unaligned_be16(geo_buf +
+			GEOMETRY_DESC_PARAM_HPB_MAX_ACTIVE_REGS);
+
+	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");
+		hpb_dev_info->hpb_disabled = true;
+		return;
+	}
+}
+
+void ufshpb_get_dev_info(struct ufs_hba *hba, u8 *desc_buf)
+{
+	struct ufshpb_dev_info *hpb_dev_info = &hba->ufshpb_dev;
+	int version;
+	u8 hpb_mode;
+
+	hpb_mode = 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__);
+		hpb_dev_info->hpb_disabled = true;
+		return;
+	}
+
+	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);
+		hpb_dev_info->hpb_disabled = true;
+		return;
+	}
+
+	/*
+	 * 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];
+}
+
+void ufshpb_init(struct ufs_hba *hba)
+{
+	struct ufshpb_dev_info *hpb_dev_info = &hba->ufshpb_dev;
+
+	if (!ufshpb_is_allowed(hba))
+		return;
+
+	atomic_set(&hpb_dev_info->slave_conf_cnt, hpb_dev_info->num_lu);
+	ufshpb_issue_hpb_reset_query(hba);
+}
+
+void ufshpb_destroy_lu(struct ufs_hba *hba, struct scsi_device *sdev)
+{
+	struct ufshpb_lu *hpb = sdev->hostdata;
+
+	if (!hpb)
+		return;
+
+	ufshpb_set_state(hpb, HPB_FAILED);
+
+	sdev = hpb->sdev_ufs_lu;
+	sdev->hostdata = NULL;
+
+	ufshpb_destroy_region_tbl(hpb);
+
+	list_del_init(&hpb->list_hpb_lu);
+
+	kfree(hpb);
+}
+
+void ufshpb_remove(struct ufs_hba *hba)
+{
+}
+
+MODULE_AUTHOR("Yongmyong Lee <ymhungry.lee@samsung.com>");
+MODULE_AUTHOR("Jinyoung Choi <j-young.choi@samsung.com>");
+MODULE_DESCRIPTION("UFS Host Performance Booster Driver");
diff --git a/drivers/scsi/ufs/ufshpb.h b/drivers/scsi/ufs/ufshpb.h
new file mode 100644
index 000000000000..3ec51c5d6edb
--- /dev/null
+++ b/drivers/scsi/ufs/ufshpb.h
@@ -0,0 +1,176 @@
+/* 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_READ_BUFFER_ID			0x01
+#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_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 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 list_head list_hpb_lu;
+};
+
+struct ufs_hba;
+struct ufshcd_lrb;
+
+#ifndef CONFIG_SCSI_UFS_HPB
+static void ufshpb_resume(struct ufs_hba *hba) {}
+static void ufshpb_suspend(struct ufs_hba *hba) {}
+static void ufshpb_reset(struct ufs_hba *hba) {}
+static void ufshpb_reset_host(struct ufs_hba *hba) {}
+static void ufshpb_rsp_upiu(struct ufs_hba *hba, struct ufshcd_lrb *lrbp) {}
+static void ufshpb_prep(struct ufs_hba *hba, struct ufshcd_lrb *lrbp) {}
+static void ufshpb_remove(struct ufs_hba *hba) {}
+static void ufshpb_init(struct ufs_hba *hba) {}
+static void ufshpb_init_hpb_lu(struct ufs_hba *hba, struct scsi_device *sdev) {}
+static void ufshpb_destroy_lu(struct ufs_hba *hba, struct scsi_device *sdev) {}
+static bool ufshpb_is_allowed(struct ufs_hba *hba) { return false; }
+static void ufshpb_get_geo_info(struct ufs_hba *hba, u8 *geo_buf) {}
+static void ufshpb_get_dev_info(struct ufs_hba *hba, u8 *desc_buf) {}
+static struct attribute *hpb_dev_attrs[] = { NULL,};
+static struct attribute_group ufs_sysfs_hpb_stat_group = {.attrs = hpb_dev_attrs,};
+#else
+void ufshpb_resume(struct ufs_hba *hba);
+void ufshpb_suspend(struct ufs_hba *hba);
+void ufshpb_reset(struct ufs_hba *hba);
+void ufshpb_reset_host(struct ufs_hba *hba);
+void ufshpb_rsp_upiu(struct ufs_hba *hba, struct ufshcd_lrb *lrbp);
+void ufshpb_prep(struct ufs_hba *hba, struct ufshcd_lrb *lrbp);
+void ufshpb_init(struct ufs_hba *hba);
+void ufshpb_init_hpb_lu(struct ufs_hba *hba, struct scsi_device *sdev);
+void ufshpb_destroy_lu(struct ufs_hba *hba, struct scsi_device *sdev);
+void ufshpb_remove(struct ufs_hba *hba);
+bool ufshpb_is_allowed(struct ufs_hba *hba);
+void ufshpb_get_geo_info(struct ufs_hba *hba, u8 *geo_buf);
+void ufshpb_get_dev_info(struct ufs_hba *hba, u8 *desc_buf);
+extern struct attribute_group ufs_sysfs_hpb_stat_group;
+#endif
+
+#endif /* End of Header */
-- 
2.17.1

[PATCH v9 3/4] 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.

Acked-by: Avri Altman <Avri.Altman@wdc.com>
Tested-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Daejun Park <daejun7.park@samsung.com>
---
 drivers/scsi/ufs/ufs.h    |  34 ++
 drivers/scsi/ufs/ufshpb.c | 996 +++++++++++++++++++++++++++++++++++++-
 drivers/scsi/ufs/ufshpb.h |  55 +++
 3 files changed, 1082 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h
index e879ac34c065..b7c1c7dd6e70 100644
--- a/drivers/scsi/ufs/ufs.h
+++ b/drivers/scsi/ufs/ufs.h
@@ -472,6 +472,39 @@ struct utp_cmd_rsp {
 	u8 sense_data[UFS_SENSE_SIZE];
 };
 
+struct ufshpb_active_field {
+	__be16 active_rgn;
+	__be16 active_srgn;
+};
+
+/**
+ * struct utp_hpb_rsp - Response UPIU structure
+ * @residual_transfer_count: Residual transfer count DW-3
+ * @reserved1: Reserved double words DW-4 to DW-7
+ * @sense_data_len: Sense data length DW-8 U16
+ * @desc_type: Descriptor type of sense data
+ * @additional_len: Additional length of sense data
+ * @hpb_type: HPB operation type
+ * @reserved2: Reserved field
+ * @active_rgn_cnt: Active region count
+ * @inactive_rgn_cnt: Inactive region count
+ * @hpb_active_field: Recommended to read HPB region and subregion
+ * @hpb_inactive_field: To be inactivated HPB region and subregion
+ */
+struct utp_hpb_rsp {
+	__be32 residual_transfer_count;
+	__be32 reserved1[4];
+	__be16 sense_data_len;
+	u8 desc_type;
+	u8 additional_len;
+	u8 hpb_type;
+	u8 reserved2;
+	u8 active_rgn_cnt;
+	u8 inactive_rgn_cnt;
+	struct ufshpb_active_field hpb_active_field[2];
+	__be16 hpb_inactive_field[2];
+};
+
 /**
  * struct utp_upiu_rsp - general upiu response structure
  * @header: UPIU header structure DW-0 to DW-2
@@ -482,6 +515,7 @@ struct utp_upiu_rsp {
 	struct utp_upiu_header header;
 	union {
 		struct utp_cmd_rsp sr;
+		struct utp_hpb_rsp hr;
 		struct utp_upiu_query qr;
 	};
 };
diff --git a/drivers/scsi/ufs/ufshpb.c b/drivers/scsi/ufs/ufshpb.c
index 7ed1868c396b..cd1a1a77ced9 100644
--- a/drivers/scsi/ufs/ufshpb.c
+++ b/drivers/scsi/ufs/ufshpb.c
@@ -16,6 +16,15 @@
 #include "ufshpb.h"
 #include "../sd.h"
 
+/* memory management */
+static struct kmem_cache *ufshpb_mctx_cache;
+static mempool_t *ufshpb_mctx_pool;
+static mempool_t *ufshpb_page_pool;
+static unsigned int ufshpb_host_map_kbytes = 1024;
+static int tot_active_srgn_pages;
+
+static struct workqueue_struct *ufshpb_wq;
+
 /* HPB enabled lu list */
 static LIST_HEAD(lh_hpb_lu);
 
@@ -24,6 +33,62 @@ bool ufshpb_is_allowed(struct ufs_hba *hba)
 	return !(hba->ufshpb_dev.hpb_disabled);
 }
 
+static bool ufshpb_is_general_lun(int lun)
+{
+	return lun < UFS_UPIU_MAX_UNIT_NUM_ID;
+}
+
+static 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 int ufshpb_may_field_valid(struct ufs_hba *hba,
+					 struct ufshcd_lrb *lrbp,
+					 struct utp_hpb_rsp *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 struct ufshpb_lu *ufshpb_get_hpb_data(struct scsi_cmnd *cmd)
+{
+	return cmd->device->hostdata;
+}
+
 static int ufshpb_get_state(struct ufshpb_lu *hpb)
 {
 	return atomic_read(&hpb->hpb_state);
@@ -38,8 +103,758 @@ void ufshpb_prep(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
 {
 }
 
+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 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 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 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->sdev_ufs_lu->sdev_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);
+}
+
+static 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->sdev_ufs_lu->sdev_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->sdev_ufs_lu->sdev_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 = 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_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_page_pool, GFP_KERNEL);
+		if (!mctx->m_page[i]) {
+			for (j = 0; j < i; j++)
+				mempool_free(mctx->m_page[j], 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_mctx_pool);
+	return NULL;
+}
+
+static 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_page_pool);
+
+	bitmap_free(mctx->ppn_dirty);
+	kmem_cache_free(hpb->m_page_cache, mctx->m_page);
+	mempool_free(mctx, 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 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 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 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 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->sdev_ufs_lu->sdev_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->sdev_ufs_lu->sdev_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 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_SRGN_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->sdev_ufs_lu->sdev_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;
+
+	if (ufshpb_get_state(hpb) != HPB_PRESENT) {
+		dev_notice(&hpb->sdev_ufs_lu->sdev_dev,
+			   "%s: ufshpb state is not PRESENT", __func__);
+		goto free_map_req;
+	}
+
+	ret = ufshpb_execute_map_req(hpb, map_req);
+	if (ret) {
+		dev_notice(&hpb->sdev_ufs_lu->sdev_dev,
+			   "%s: issue map_req failed: %d, region %d - %d\n",
+			   __func__, ret, srgn->rgn_idx, srgn->srgn_idx);
+		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->sdev_ufs_lu->sdev_dev,
+				    "cannot get victim region error\n");
+				ret = -ENOMEM;
+				goto out;
+			}
+
+			dev_dbg(&hpb->sdev_ufs_lu->sdev_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 utp_hpb_rsp *rsp_field)
+{
+	int i, rgn_idx, srgn_idx;
+
+	BUILD_BUG_ON(sizeof(struct ufshpb_active_field) != 4);
+	/*
+	 * 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->sdev_ufs_lu->sdev_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->sdev_ufs_lu->sdev_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->sdev_ufs_lu->sdev_dev, "Noti: #ACT %u #INACT %u\n",
+		rsp_field->active_rgn_cnt, rsp_field->inactive_rgn_cnt);
+
+	queue_work(ufshpb_wq, &hpb->map_work);
+}
+
+/*
+ * This function will parse recommended active subregion information in sense
+ * data field of response UPIU with SAM_STAT_GOOD state.
+ */
 void ufshpb_rsp_upiu(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
 {
+	struct ufshpb_lu *hpb = ufshpb_get_hpb_data(lrbp->cmd);
+	struct utp_hpb_rsp *rsp_field;
+	int data_seg_len;
+
+	if (!hpb)
+		return;
+
+	if (ufshpb_get_state(hpb) != HPB_PRESENT) {
+		dev_notice(&hpb->sdev_ufs_lu->sdev_dev,
+			   "%s: ufshpb state is not PRESENT", __func__);
+		return;
+	}
+
+	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;
+
+		if (!ufshpb_is_empty_rsp_lists(hpb))
+			queue_work(ufshpb_wq, &hpb->map_work);
+		return;
+	}
+
+	/* Check HPB_UPDATE_ALERT */
+	if (!(lrbp->ucd_rsp_ptr->header.dword_2 &
+	      UPIU_HEADER_DWORD(0, 2, 0, 0)))
+		return;
+
+	rsp_field = &lrbp->ucd_rsp_ptr->hr;
+	BUILD_BUG_ON(sizeof(struct utp_hpb_rsp) != 40);
+
+	if (ufshpb_may_field_valid(hba, lrbp, rsp_field))
+		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->sdev_ufs_lu->sdev_dev,
+			 "UFS device lost HPB information during PM.\n");
+		break;
+	default:
+		dev_notice(&hpb->sdev_ufs_lu->sdev_dev,
+			   "hpb_type is not available: %d\n",
+			   rsp_field->hpb_type);
+		break;
+	}
+}
+
+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))) {
+		if (ufshpb_get_state(hpb) == HPB_SUSPEND) {
+			dev_info(&hpb->sdev_ufs_lu->sdev_dev, "HPB suspend");
+			break;
+		}
+		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)
+			goto active_failed;
+
+		ret = ufshpb_issue_map_req(hpb, rgn, srgn);
+		if (ret) {
+			dev_notice(&hpb->sdev_ufs_lu->sdev_dev,
+			    "issue map_req failed. ret %d, region %d - %d\n",
+			    ret, rgn->rgn_idx, srgn->srgn_idx);
+			goto active_failed;
+		}
+		spin_lock_irqsave(&hpb->rsp_list_lock, flags);
+	}
+	spin_unlock_irqrestore(&hpb->rsp_list_lock, flags);
+	return;
+
+active_failed:
+	dev_notice(&hpb->sdev_ufs_lu->sdev_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))) {
+		if (ufshpb_get_state(hpb) == HPB_SUSPEND) {
+			dev_info(&hpb->sdev_ufs_lu->sdev_dev, "HPB suspend");
+			break;
+		}
+		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 = container_of(work, struct ufshpb_lu, map_work);
+
+	if (ufshpb_get_state(hpb) != HPB_PRESENT) {
+		dev_notice(&hpb->sdev_ufs_lu->sdev_dev,
+			   "%s: ufshpb state is not PRESENT", __func__);
+		return;
+	}
+
+	ufshpb_run_inactive_region_list(hpb);
+	ufshpb_run_active_subregion_list(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,
@@ -50,6 +865,8 @@ 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;
@@ -81,6 +898,8 @@ 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;
@@ -133,6 +952,9 @@ 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;
@@ -142,7 +964,13 @@ 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;
@@ -166,7 +994,10 @@ 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);
+		}
 	}
 }
 
@@ -242,12 +1073,46 @@ 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;
 
 	ufshpb_stat_init(hpb);
 
 	return 0;
+
+release_m_page_cache:
+	kmem_cache_destroy(hpb->m_page_cache);
+release_req_cache:
+	kmem_cache_destroy(hpb->map_req_cache);
+	return ret;
 }
 
 static struct ufshpb_lu *ufshpb_alloc_hpb_lu(struct ufs_hba *hba, int lun,
@@ -278,6 +1143,34 @@ 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 void ufshpb_cancel_jobs(struct ufshpb_lu *hpb)
+{
+	cancel_work_sync(&hpb->map_work);
+}
+
+
 static void ufshpb_issue_hpb_reset_query(struct ufs_hba *hba)
 {
 	int err = 0;
@@ -355,6 +1248,8 @@ void ufshpb_reset_host(struct ufs_hba *hba)
 		if (ufshpb_get_state(hpb) != HPB_PRESENT)
 			continue;
 		ufshpb_set_state(hpb, HPB_RESET);
+		ufshpb_cancel_jobs(hpb);
+		ufshpb_discard_rsp_lists(hpb);
 	}
 }
 
@@ -368,6 +1263,7 @@ void ufshpb_suspend(struct ufs_hba *hba)
 		if (ufshpb_get_state(hpb) != HPB_PRESENT)
 			continue;
 		ufshpb_set_state(hpb, HPB_SUSPEND);
+		ufshpb_cancel_jobs(hpb);
 	}
 }
 
@@ -382,6 +1278,8 @@ void ufshpb_resume(struct ufs_hba *hba)
 		    (ufshpb_get_state(hpb) != HPB_SUSPEND))
 			continue;
 		ufshpb_set_state(hpb, HPB_PRESENT);
+		if (!ufshpb_is_empty_rsp_lists(hpb))
+			queue_work(ufshpb_wq, &hpb->map_work);
 	}
 }
 
@@ -449,16 +1347,35 @@ static int ufshpb_get_lu_info(struct ufs_hba *hba, int lun,
 
 static void ufshpb_hpb_lu_prepared(struct ufs_hba *hba)
 {
+	int pool_size;
 	struct ufshpb_lu *hpb;
 
-	if (list_empty(&lh_hpb_lu))
+	if (list_empty(&lh_hpb_lu)) {
+		ufshpb_remove(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_mctx_pool, tot_active_srgn_pages);
+		mempool_resize(ufshpb_page_pool, tot_active_srgn_pages);
+	}
+
 	list_for_each_entry(hpb, &lh_hpb_lu, list_hpb_lu) {
 		dev_info(hba->dev, "set state to present\n");
 		ufshpb_set_state(hpb, HPB_PRESENT);
+
+		if ((hpb->lu_pinned_end - hpb->lu_pinned_start) > 0) {
+			dev_info(hba->dev,
+			    "loading pinned regions %d - %d\n",
+			    hpb->lu_pinned_start, hpb->lu_pinned_end);
+			queue_work(ufshpb_wq, &hpb->map_work);
+		}
 	}
 }
 
@@ -486,6 +1403,9 @@ void ufshpb_init_hpb_lu(struct ufs_hba *hba, struct scsi_device *sdev)
 	if (!hpb)
 		goto release_desc_buf;
 
+	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;
 
@@ -499,6 +1419,57 @@ void ufshpb_init_hpb_lu(struct ufs_hba *hba, struct scsi_device *sdev)
 		ufshpb_hpb_lu_prepared(hba);
 }
 
+static int ufshpb_init_mem_wq(void)
+{
+	int ret;
+	unsigned int pool_size;
+
+	ufshpb_mctx_cache = kmem_cache_create("ufshpb_mctx_cache",
+					sizeof(struct ufshpb_map_ctx),
+					0, 0, NULL);
+	if (!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_mctx_pool = mempool_create_slab_pool(pool_size,
+						    ufshpb_mctx_cache);
+	if (!ufshpb_mctx_pool) {
+		pr_err("ufshpb: cannot init mctx pool\n");
+		ret = -ENOMEM;
+		goto release_mctx_cache;
+	}
+
+	ufshpb_page_pool = mempool_create_page_pool(pool_size, 0);
+	if (!ufshpb_page_pool) {
+		pr_err("ufshpb: cannot init page pool\n");
+		ret = -ENOMEM;
+		goto release_mctx_pool;
+	}
+
+	ufshpb_wq = alloc_workqueue("ufshpb-wq",
+					WQ_UNBOUND | WQ_MEM_RECLAIM, 0);
+	if (!ufshpb_wq) {
+		pr_err("ufshpb: alloc workqueue failed\n");
+		ret = -ENOMEM;
+		goto release_page_pool;
+	}
+
+	return 0;
+
+release_page_pool:
+	mempool_destroy(ufshpb_page_pool);
+release_mctx_pool:
+	mempool_destroy(ufshpb_mctx_pool);
+release_mctx_cache:
+	kmem_cache_destroy(ufshpb_mctx_cache);
+	return ret;
+}
+
 void ufshpb_get_geo_info(struct ufs_hba *hba, u8 *geo_buf)
 {
 	struct ufshpb_dev_info *hpb_dev_info = &hba->ufshpb_dev;
@@ -564,7 +1535,11 @@ void ufshpb_init(struct ufs_hba *hba)
 	if (!ufshpb_is_allowed(hba))
 		return;
 
+	if (ufshpb_init_mem_wq())
+		return;
+
 	atomic_set(&hpb_dev_info->slave_conf_cnt, hpb_dev_info->num_lu);
+	tot_active_srgn_pages = 0;
 	ufshpb_issue_hpb_reset_query(hba);
 }
 
@@ -580,8 +1555,13 @@ void ufshpb_destroy_lu(struct ufs_hba *hba, struct scsi_device *sdev)
 	sdev = hpb->sdev_ufs_lu;
 	sdev->hostdata = NULL;
 
+	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);
 
 	kfree(hpb);
@@ -589,8 +1569,18 @@ void ufshpb_destroy_lu(struct ufs_hba *hba, struct scsi_device *sdev)
 
 void ufshpb_remove(struct ufs_hba *hba)
 {
+	mempool_destroy(ufshpb_page_pool);
+	mempool_destroy(ufshpb_mctx_pool);
+	kmem_cache_destroy(ufshpb_mctx_cache);
+
+	destroy_workqueue(ufshpb_wq);
+
+	dev_info(hba->dev, "ufshpb: remove success\n");
 }
 
+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");
 MODULE_AUTHOR("Yongmyong Lee <ymhungry.lee@samsung.com>");
 MODULE_AUTHOR("Jinyoung Choi <j-young.choi@samsung.com>");
 MODULE_DESCRIPTION("UFS Host Performance Booster Driver");
diff --git a/drivers/scsi/ufs/ufshpb.h b/drivers/scsi/ufs/ufshpb.h
index 3ec51c5d6edb..6e9b82082956 100644
--- a/drivers/scsi/ufs/ufshpb.h
+++ b/drivers/scsi/ufs/ufshpb.h
@@ -86,10 +86,19 @@ struct ufshpb_lu_info {
 	int max_active_rgns;
 };
 
+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 {
@@ -97,6 +106,39 @@ 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 {
@@ -116,6 +158,16 @@ 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;
@@ -134,6 +186,9 @@ struct ufshpb_lu {
 
 	struct ufshpb_stats stats;
 
+	struct kmem_cache *map_req_cache;
+	struct kmem_cache *m_page_cache;
+
 	struct list_head list_hpb_lu;
 };
 
-- 
2.17.1

[PATCH v9 4/4] 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.

Acked-by: Avri Altman <Avri.Altman@wdc.com>
Tested-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Daejun Park <daejun7.park@samsung.com>
---
 drivers/scsi/ufs/ufshpb.c | 231 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 231 insertions(+)

diff --git a/drivers/scsi/ufs/ufshpb.c b/drivers/scsi/ufs/ufshpb.c
index cd1a1a77ced9..9b4f7fc41dc4 100644
--- a/drivers/scsi/ufs/ufshpb.c
+++ b/drivers/scsi/ufs/ufshpb.c
@@ -33,6 +33,29 @@ bool ufshpb_is_allowed(struct ufs_hba *hba)
 	return !(hba->ufshpb_dev.hpb_disabled);
 }
 
+static 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 bool ufshpb_is_read_cmd(struct scsi_cmnd *cmd)
+{
+	return req_op(cmd->request) == REQ_OP_READ;
+}
+
+static 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 bool ufshpb_is_support_chunk(int transfer_len)
+{
+	return transfer_len <= HPB_MULTI_CHUNK_HIGH;
+}
+
 static bool ufshpb_is_general_lun(int lun)
 {
 	return lun < UFS_UPIU_MAX_UNIT_NUM_ID;
@@ -99,8 +122,216 @@ static void ufshpb_set_state(struct ufshpb_lu *hpb, int state)
 	atomic_set(&hpb->hpb_state, state);
 }
 
+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->sdev_ufs_lu->sdev_dev,
+			"error. cannot find page in mctx\n");
+		return 0;
+	}
+
+	ppn_table = page_address(page);
+	if (unlikely(!ppn_table)) {
+		*error = -ENOMEM;
+		dev_err(&hpb->sdev_ufs_lu->sdev_dev,
+			"error. cannot get ppn_table\n");
+		return 0;
+	}
+
+	return ppn_table[offset];
+}
+
+static 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;
+}
+
+/*
+ * This function will set up HPB read command using host-side L2P map data.
+ * In HPB v1.0, maximum size of HPB read command is 4KB.
+ */
 void ufshpb_prep(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);
+	if (!hpb)
+		return;
+
+	if (ufshpb_get_state(hpb) != HPB_PRESENT) {
+		dev_notice(&hpb->sdev_ufs_lu->sdev_dev,
+			   "%s: ufshpb state is not PRESENT", __func__);
+		return;
+	}
+
+	WARN_ON(hpb->lun != cmd->device->lun);
+	if (!ufshpb_is_write_discard_cmd(cmd) &&
+	    !ufshpb_is_read_cmd(cmd))
+		return;
+
+	transfer_len = sectors_to_logical(cmd->device, blk_rq_sectors(cmd->request));
+	if (unlikely(!transfer_len))
+		return;
+
+	lpn = sectors_to_logical(cmd->device, blk_rq_pos(cmd->request));
+	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);
+		return;
+	}
+
+	WARN_ON(!ufshpb_is_read_cmd(cmd));
+
+	if (!ufshpb_is_support_chunk(transfer_len))
+		return;
+
+	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);
+		return;
+	}
+
+	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(hba->dev, "ufshpb_get_ppn failed. err %d\n", err);
+		return;
+	}
+
+	ufshpb_set_hpb_read_to_upiu(hpb, lrbp, lpn, ppn, transfer_len);
+
+	atomic_inc(&hpb->stats.hit_cnt);
 }
 
 static struct ufshpb_req *ufshpb_get_map_req(struct ufshpb_lu *hpb,
-- 
2.17.1

Re: [PATCH v9 2/4] scsi: ufs: Introduce HPB feature

[Bart Van Assche]

On 2020-08-28 00:18, Daejun Park wrote:
> diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
> index 618b253e5ec8..df30622a2b67 100644
> --- a/drivers/scsi/ufs/ufshcd.h
> +++ b/drivers/scsi/ufs/ufshcd.h
> @@ -588,6 +588,24 @@ struct ufs_hba_variant_params {
>  	u16 hba_enable_delay_us;
>  	u32 wb_flush_threshold;
>  };
> +#ifdef CONFIG_SCSI_UFS_HPB
> +/**
> + * 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
> + * @slave_conf_cnt: counter to check all lu finished initialization
> + * @hpb_disabled: flag to check if HPB is disabled
> + */
> +struct ufshpb_dev_info {
> +	int num_lu;
> +	int rgn_size;
> +	int srgn_size;
> +	atomic_t slave_conf_cnt;
> +	bool hpb_disabled;
> +};
> +#endif

Please insert a blank line above "#ifdef CONFIG_SCSI_UFS_HPB"

> +/* HPB enabled lu list */
> +static LIST_HEAD(lh_hpb_lu);

Is it necessary to maintain this list? Or in other words, is it possible to
change all list_for_each_entry(hpb, &lh_hpb_lu, list_hpb_lu) calls into
shost_for_each_device() calls?

> +/* SYSFS functions */
> +#define ufshpb_sysfs_attr_show_func(__name)				\
> +static ssize_t __name##_show(struct device *dev,			\
> +	struct device_attribute *attr, char *buf)			\
> +{									\
> +	struct scsi_device *sdev = to_scsi_device(dev);			\
> +	struct ufshpb_lu *hpb = sdev->hostdata;				\
> +	if (!hpb)							\
> +		return -ENOENT;						\
> +	return snprintf(buf, PAGE_SIZE, "%d\n",				\
> +			atomic_read(&hpb->stats.__name));		\
> +}									\
> +static DEVICE_ATTR_RO(__name)

Please leave a blank line after declarations (between the "hpb" declaration
and "if (!hpb)").

> +#ifndef CONFIG_SCSI_UFS_HPB
> +[...]
> +static struct attribute *hpb_dev_attrs[] = { NULL,};
> +static struct attribute_group ufs_sysfs_hpb_stat_group = {.attrs = hpb_dev_attrs,};
> +#else
> +[...]
> +extern struct attribute_group ufs_sysfs_hpb_stat_group;
> +#endif

Defining static variables or arrays in header files is questionable because
the definition of these variables will be duplicated in each source file that
header file is included in. Although the general rule for kernel code is to
confine #ifdefs to header files, for ufs_sysfs_hpb_stat_group I think that
it is better to surround its use with #ifndef CONFIG_SCSI_UFS_HPB / #endif
instead of defining a dummy structure as static variable in a header file if
HPB support is disabled.

Otherwise this patch looks good to me.

Thanks,

Bart.

Re: [PATCH v9 1/4] scsi: ufs: Add HPB feature related parameters

[Bart Van Assche]

On 2020-08-28 00:17, Daejun Park wrote:
> This is a patch for parameters to be used for HPB feature.

Reviewed-by: Bart Van Assche <bvanassche@acm.org>

Re: [PATCH v9 3/4] scsi: ufs: L2P map management for HPB read

[Bart Van Assche]

On 2020-08-28 00:19, Daejun Park wrote:
> +static unsigned int ufshpb_host_map_kbytes = 1024;

A comment that explains where this value comes from would be welcome.

> +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);

Why BLK_MQ_REQ_PREEMPT? Since this code is only executed while medium access
commands are processed and since none of these commands have the PREEMPT flag
set I think that the PREEMPT flag should be left out. Otherwise there probably
will be weird interactions with runtime suspended devices.

Is it acceptable that the above blk_get_request() call blocks if a UFS device
has been runtime suspended? If not, consider using the flag BLK_MQ_REQ_NOWAIT
instead.

> +	bio = bio_alloc(GFP_KERNEL, hpb->pages_per_srgn);
> +	if (!bio) {
> +		blk_put_request(req);
> +		goto free_map_req;
> +	}

If the blk_get_request() would be modified such that it doesn't wait, this
call may have to be modified too (GFP_NOWAIT?).

> +	if (rgn->rgn_state == HPB_RGN_INACTIVE) {
> +		if (atomic_read(&lru_info->active_cnt)
> +		    == lru_info->max_lru_active_cnt) {

When splitting a line, please put comparison operators at the end of the line
instead of at the start, e.g. as follows:

		if (atomic_read(&lru_info->active_cnt) ==
		    lru_info->max_lru_active_cnt) {

> +	pool_size = DIV_ROUND_UP(ufshpb_host_map_kbytes * 1024, PAGE_SIZE);

Please use PAGE_ALIGN() to align to the next page boundary.

Thanks,

Bart.

Re: [PATCH v9 4/4] scsi: ufs: Prepare HPB read for cached sub-region

[Bart Van Assche]

On 2020-08-28 00:19, Daejun Park wrote:
> This patch changes the read I/O to the HPB read I/O.

Reviewed-by: Bart Van Assche <bvanassche@acm.org>

Re: [PATCH v9 3/4] scsi: ufs: L2P map management for HPB read

[Daejun Park]

Hi Bart,
> > +static unsigned int ufshpb_host_map_kbytes = 1024;
> 
> A comment that explains where this value comes from would be welcome.

I will add a follows comment and change defalut value 1024 to 2048. 
"A cache size of 2MB can cache ppn in the 1GB range."

> > +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);
> 
> Why BLK_MQ_REQ_PREEMPT? Since this code is only executed while medium access
> commands are processed and since none of these commands have the PREEMPT flag
> set I think that the PREEMPT flag should be left out. Otherwise there probably
> will be weird interactions with runtime suspended devices.

OK, I will remove BLK_MQ_REQ_PREEMPT flag.

> Is it acceptable that the above blk_get_request() call blocks if a UFS device
> has been runtime suspended? If not, consider using the flag BLK_MQ_REQ_NOWAIT
> instead.

The map worker don't issue map requests when the UFS device is in 
runtime suspend. So, I think BLK_MQ_REQ_NOWAIT flags is not needed.

> > +	bio = bio_alloc(GFP_KERNEL, hpb->pages_per_srgn);
> > +	if (!bio) {
> > +		blk_put_request(req);
> > +		goto free_map_req;
> > +	}
> 
> If the blk_get_request() would be modified such that it doesn't wait, this
> call may have to be modified too (GFP_NOWAIT?).
>
> > +	if (rgn->rgn_state == HPB_RGN_INACTIVE) {
> > +		if (atomic_read(&lru_info->active_cnt)
> > +		    == lru_info->max_lru_active_cnt) {
> 
> When splitting a line, please put comparison operators at the end of the line
> instead of at the start, e.g. as follows:
> 
> 		if (atomic_read(&lru_info->active_cnt) ==
> 		    lru_info->max_lru_active_cnt) {

OK, I will change it.
 
> > +	pool_size = DIV_ROUND_UP(ufshpb_host_map_kbytes * 1024, PAGE_SIZE);
> 
> Please use PAGE_ALIGN() to align to the next page boundary.

OK, I will.

Thanks,
Daejun.

Re: [PATCH v9 2/4] scsi: ufs: Introduce HPB feature

[Daejun Park]

Hi, Bart

> > diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
> > index 618b253e5ec8..df30622a2b67 100644
> > --- a/drivers/scsi/ufs/ufshcd.h
> > +++ b/drivers/scsi/ufs/ufshcd.h
> > @@ -588,6 +588,24 @@ struct ufs_hba_variant_params {
> >  	u16 hba_enable_delay_us;
> >  	u32 wb_flush_threshold;
> >  };
> > +#ifdef CONFIG_SCSI_UFS_HPB
> > +/**
> > + * 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
> > + * @slave_conf_cnt: counter to check all lu finished initialization
> > + * @hpb_disabled: flag to check if HPB is disabled
> > + */
> > +struct ufshpb_dev_info {
> > +	int num_lu;
> > +	int rgn_size;
> > +	int srgn_size;
> > +	atomic_t slave_conf_cnt;
> > +	bool hpb_disabled;
> > +};
> > +#endif
> 
> Please insert a blank line above "#ifdef CONFIG_SCSI_UFS_HPB"

OK, I will insert a blank line.
 
> > +/* HPB enabled lu list */
> > +static LIST_HEAD(lh_hpb_lu);
> 
> Is it necessary to maintain this list? Or in other words, is it possible to
> change all list_for_each_entry(hpb, &lh_hpb_lu, list_hpb_lu) calls into
> shost_for_each_device() calls?

OK, I will remove lh_hpb_lu.

> > +/* SYSFS functions */
> > +#define ufshpb_sysfs_attr_show_func(__name)				\
> > +static ssize_t __name##_show(struct device *dev,			\
> > +	struct device_attribute *attr, char *buf)			\
> > +{									\
> > +	struct scsi_device *sdev = to_scsi_device(dev);			\
> > +	struct ufshpb_lu *hpb = sdev->hostdata;				\
> > +	if (!hpb)							\
> > +		return -ENOENT;						\
> > +	return snprintf(buf, PAGE_SIZE, "%d\n",				\
> > +			atomic_read(&hpb->stats.__name));		\
> > +}									\
> > +static DEVICE_ATTR_RO(__name)
> 
> Please leave a blank line after declarations (between the "hpb" declaration
> and "if (!hpb)").

OK, I will add a blank line.

> > +#ifndef CONFIG_SCSI_UFS_HPB
> > +[...]
> > +static struct attribute *hpb_dev_attrs[] = { NULL,};
> > +static struct attribute_group ufs_sysfs_hpb_stat_group = {.attrs = hpb_dev_attrs,};
> > +#else
> > +[...]
> > +extern struct attribute_group ufs_sysfs_hpb_stat_group;
> > +#endif
> 
> Defining static variables or arrays in header files is questionable because
> the definition of these variables will be duplicated in each source file that
> header file is included in. Although the general rule for kernel code is to
> confine #ifdefs to header files, for ufs_sysfs_hpb_stat_group I think that
> it is better to surround its use with #ifndef CONFIG_SCSI_UFS_HPB / #endif
> instead of defining a dummy structure as static variable in a header file if
> HPB support is disabled.

OK, I added #ifdef in ufshcd.c.

static const struct attribute_group *ufshcd_driver_groups[] = {
	&ufs_sysfs_unit_descriptor_group,
	&ufs_sysfs_lun_attributes_group,
#ifdef CONFIG_SCSI_UFS_HPB
	&ufs_sysfs_hpb_stat_group,
#endif
	NULL,
};

Thanks,
Daejun