[PATCH 2/8] scsi: ufshpb: Add host control mode support to rsp_upiu

[Avri Altman]

There are some limitations to activations / inactivations in host
control mode - Add those.

Signed-off-by: Avri Altman <avri.altman@xxxxxxx>
---
 drivers/scsi/ufs/ufshpb.c | 35 +++++++++++++++++++++++++++++++++++
 drivers/scsi/ufs/ufshpb.h |  6 ++++++
 2 files changed, 41 insertions(+)

diff --git a/drivers/scsi/ufs/ufshpb.c b/drivers/scsi/ufs/ufshpb.c
index 183bdf35f2d0..5fa1f5bc08e6 100644
--- a/drivers/scsi/ufs/ufshpb.c
+++ b/drivers/scsi/ufs/ufshpb.c
@@ -140,6 +140,8 @@ static void ufshpb_set_ppn_dirty(struct ufshpb_lu *hpb, int rgn_idx,
 	else
 		set_bit_len = cnt;
 
+	set_bit(RGN_FLAG_DIRTY, &rgn->rgn_flags);
+
 	if (rgn->rgn_state != HPB_RGN_INACTIVE &&
 	    srgn->srgn_state == HPB_SRGN_VALID)
 		bitmap_set(srgn->mctx->ppn_dirty, srgn_offset, set_bit_len);
@@ -201,6 +203,11 @@ static bool ufshpb_test_ppn_dirty(struct ufshpb_lu *hpb, int rgn_idx,
 	return false;
 }
 
+static inline bool is_rgn_dirty(struct ufshpb_region *rgn)
+{
+	return test_bit(RGN_FLAG_DIRTY, &rgn->rgn_flags);
+}
+
 static u64 ufshpb_get_ppn(struct ufshpb_lu *hpb,
 			  struct ufshpb_map_ctx *mctx, int pos, int *error)
 {
@@ -380,8 +387,12 @@ static void ufshpb_put_map_req(struct ufshpb_lu *hpb,
 static int ufshpb_clear_dirty_bitmap(struct ufshpb_lu *hpb,
 				     struct ufshpb_subregion *srgn)
 {
+	struct ufshpb_region *rgn;
+
 	WARN_ON(!srgn->mctx);
 	bitmap_zero(srgn->mctx->ppn_dirty, hpb->entries_per_srgn);
+	rgn = hpb->rgn_tbl + srgn->rgn_idx;
+	clear_bit(RGN_FLAG_DIRTY, &rgn->rgn_flags);
 	return 0;
 }
 
@@ -814,17 +825,39 @@ static void ufshpb_rsp_req_region_update(struct ufshpb_lu *hpb,
 	 */
 	spin_lock(&hpb->rsp_list_lock);
 	for (i = 0; i < rsp_field->active_rgn_cnt; i++) {
+		struct ufshpb_region *rgn;
+
 		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);
 
+		rgn = hpb->rgn_tbl + rgn_idx;
+		if (ufshpb_mode == HPB_HOST_CONTROL &&
+		    (rgn->rgn_state != HPB_RGN_ACTIVE || is_rgn_dirty(rgn))) {
+			/*
+			 * in host control mode, subregion activation
+			 * recommendations are only allowed to active regions.
+			 * Also, ignore recommendations for dirty regions - the
+			 * host will make decisions concerning those by himself
+			 */
+			continue;
+		}
+
 		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);
 		hpb->stats.rb_active_cnt++;
 	}
 
+	if (ufshpb_mode == HPB_HOST_CONTROL) {
+		/*
+		 * in host control mode the device is not allowed to inactivate
+		 * regions
+		 */
+		goto out_unlock;
+	}
+
 	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,
@@ -832,6 +865,8 @@ static void ufshpb_rsp_req_region_update(struct ufshpb_lu *hpb,
 		ufshpb_update_inactive_info(hpb, rgn_idx);
 		hpb->stats.rb_inactive_cnt++;
 	}
+
+out_unlock:
 	spin_unlock(&hpb->rsp_list_lock);
 
 	dev_dbg(&hpb->sdev_ufs_lu->sdev_dev, "Noti: #ACT %u #INACT %u\n",
diff --git a/drivers/scsi/ufs/ufshpb.h b/drivers/scsi/ufs/ufshpb.h
index 2c43a03b66b6..8a34b0f42754 100644
--- a/drivers/scsi/ufs/ufshpb.h
+++ b/drivers/scsi/ufs/ufshpb.h
@@ -48,6 +48,11 @@ enum UFSHPB_MODE {
 	HPB_DEVICE_CONTROL,
 };
 
+enum HPB_RGN_FLAGS {
+	RGN_FLAG_UPDATE = 0,
+	RGN_FLAG_DIRTY,
+};
+
 enum UFSHPB_STATE {
 	HPB_PRESENT = 1,
 	HPB_SUSPEND,
@@ -109,6 +114,7 @@ struct ufshpb_region {
 
 	/* below information is used by lru */
 	struct list_head list_lru_rgn;
+	unsigned long rgn_flags;
 };
 
 #define for_each_sub_region(rgn, i, srgn)				\
-- 
2.25.1