Merge patch series "scsi: ufs: core: Always read the descriptors with max length"

Arthur Simchaev <Arthur.Simchaev@wdc.com> says:

Read any descriptor with a maximum size of QUERY_DESC_MAX_SIZE.
According to the spec the device returns the actual size.  Thus can
improve code readability and save CPU cycles.  While at it, clean up
few leftovers around the descriptor size parameter.

Link: https://lore.kernel.org/r/1670763911-8695-1-git-send-email-Arthur.Simchaev@wdc.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 25 insertions, 78 deletions

diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 1fe16aebc139..99ca5b035028 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -3400,37 +3400,6 @@ int ufshcd_query_descriptor_retry(struct ufs_hba *hba,
 }
 
 /**
- * ufshcd_map_desc_id_to_length - map descriptor IDN to its length
- * @hba: Pointer to adapter instance
- * @desc_id: descriptor idn value
- * @desc_len: mapped desc length (out)
- */
-void ufshcd_map_desc_id_to_length(struct ufs_hba *hba, enum desc_idn desc_id,
-				  int *desc_len)
-{
-	if (desc_id >= QUERY_DESC_IDN_MAX || desc_id == QUERY_DESC_IDN_RFU_0 ||
-	    desc_id == QUERY_DESC_IDN_RFU_1)
-		*desc_len = 0;
-	else
-		*desc_len = hba->desc_size[desc_id];
-}
-EXPORT_SYMBOL(ufshcd_map_desc_id_to_length);
-
-static void ufshcd_update_desc_length(struct ufs_hba *hba,
-				      enum desc_idn desc_id, int desc_index,
-				      unsigned char desc_len)
-{
-	if (hba->desc_size[desc_id] == QUERY_DESC_MAX_SIZE &&
-	    desc_id != QUERY_DESC_IDN_STRING && desc_index != UFS_RPMB_UNIT)
-		/* For UFS 3.1, the normal unit descriptor is 10 bytes larger
-		 * than the RPMB unit, however, both descriptors share the same
-		 * desc_idn, to cover both unit descriptors with one length, we
-		 * choose the normal unit descriptor length by desc_index.
-		 */
-		hba->desc_size[desc_id] = desc_len;
-}
-
-/**
  * ufshcd_read_desc_param - read the specified descriptor parameter
  * @hba: Pointer to adapter instance
  * @desc_id: descriptor idn value
@@ -3450,26 +3419,13 @@ int ufshcd_read_desc_param(struct ufs_hba *hba,
 {
 	int ret;
 	u8 *desc_buf;
-	int buff_len;
+	int buff_len = QUERY_DESC_MAX_SIZE;
 	bool is_kmalloc = true;
 
 	/* Safety check */
 	if (desc_id >= QUERY_DESC_IDN_MAX || !param_size)
 		return -EINVAL;
 
-	/* Get the length of descriptor */
-	ufshcd_map_desc_id_to_length(hba, desc_id, &buff_len);
-	if (!buff_len) {
-		dev_err(hba->dev, "%s: Failed to get desc length\n", __func__);
-		return -EINVAL;
-	}
-
-	if (param_offset >= buff_len) {
-		dev_err(hba->dev, "%s: Invalid offset 0x%x in descriptor IDN 0x%x, length 0x%x\n",
-			__func__, param_offset, desc_id, buff_len);
-		return -EINVAL;
-	}
-
 	/* Check whether we need temp memory */
 	if (param_offset != 0 || param_size < buff_len) {
 		desc_buf = kzalloc(buff_len, GFP_KERNEL);
@@ -3482,15 +3438,23 @@ int ufshcd_read_desc_param(struct ufs_hba *hba,
 
 	/* Request for full descriptor */
 	ret = ufshcd_query_descriptor_retry(hba, UPIU_QUERY_OPCODE_READ_DESC,
-					desc_id, desc_index, 0,
-					desc_buf, &buff_len);
-
+					    desc_id, desc_index, 0,
+					    desc_buf, &buff_len);
 	if (ret) {
 		dev_err(hba->dev, "%s: Failed reading descriptor. desc_id %d, desc_index %d, param_offset %d, ret %d\n",
 			__func__, desc_id, desc_index, param_offset, ret);
 		goto out;
 	}
 
+	/* Update descriptor length */
+	buff_len = desc_buf[QUERY_DESC_LENGTH_OFFSET];
+
+	if (param_offset >= buff_len) {
+		dev_err(hba->dev, "%s: Invalid offset 0x%x in descriptor IDN 0x%x, length 0x%x\n",
+			__func__, param_offset, desc_id, buff_len);
+		return -EINVAL;
+	}
+
 	/* Sanity check */
 	if (desc_buf[QUERY_DESC_DESC_TYPE_OFFSET] != desc_id) {
 		dev_err(hba->dev, "%s: invalid desc_id %d in descriptor header\n",
@@ -3499,10 +3463,6 @@ int ufshcd_read_desc_param(struct ufs_hba *hba,
 		goto out;
 	}
 
-	/* Update descriptor length */
-	buff_len = desc_buf[QUERY_DESC_LENGTH_OFFSET];
-	ufshcd_update_desc_length(hba, desc_id, desc_index, buff_len);
-
 	if (is_kmalloc) {
 		/* Make sure we don't copy more data than available */
 		if (param_offset >= buff_len)
@@ -4940,7 +4900,7 @@ static void ufshcd_setup_links(struct ufs_hba *hba, struct scsi_device *sdev)
  */
 static void ufshcd_lu_init(struct ufs_hba *hba, struct scsi_device *sdev)
 {
-	int len = hba->desc_size[QUERY_DESC_IDN_UNIT];
+	int len = QUERY_DESC_MAX_SIZE;
 	u8 lun = ufshcd_scsi_to_upiu_lun(sdev->lun);
 	u8 lun_qdepth = hba->nutrs;
 	u8 *desc_buf;
@@ -7564,12 +7524,11 @@ static u32 ufshcd_get_max_icc_level(int sup_curr_uA, u32 start_scan,
  * In case regulators are not initialized we'll return 0
  * @hba: per-adapter instance
  * @desc_buf: power descriptor buffer to extract ICC levels from.
- * @len: length of desc_buff
  *
  * Returns calculated ICC level
  */
 static u32 ufshcd_find_max_sup_active_icc_level(struct ufs_hba *hba,
-						const u8 *desc_buf, int len)
+						const u8 *desc_buf)
 {
 	u32 icc_level = 0;
 
@@ -7611,25 +7570,23 @@ out:
 static void ufshcd_set_active_icc_lvl(struct ufs_hba *hba)
 {
 	int ret;
-	int buff_len = hba->desc_size[QUERY_DESC_IDN_POWER];
 	u8 *desc_buf;
 	u32 icc_level;
 
-	desc_buf = kmalloc(buff_len, GFP_KERNEL);
+	desc_buf = kzalloc(QUERY_DESC_MAX_SIZE, GFP_KERNEL);
 	if (!desc_buf)
 		return;
 
 	ret = ufshcd_read_desc_param(hba, QUERY_DESC_IDN_POWER, 0, 0,
-				     desc_buf, buff_len);
+				     desc_buf, QUERY_DESC_MAX_SIZE);
 	if (ret) {
 		dev_err(hba->dev,
-			"%s: Failed reading power descriptor.len = %d ret = %d",
-			__func__, buff_len, ret);
+			"%s: Failed reading power descriptor ret = %d",
+			__func__, ret);
 		goto out;
 	}
 
-	icc_level = ufshcd_find_max_sup_active_icc_level(hba, desc_buf,
-							 buff_len);
+	icc_level = ufshcd_find_max_sup_active_icc_level(hba, desc_buf);
 	dev_dbg(hba->dev, "%s: setting icc_level 0x%x", __func__, icc_level);
 
 	ret = ufshcd_query_attr_retry(hba, UPIU_QUERY_OPCODE_WRITE_ATTR,
@@ -7739,10 +7696,6 @@ static void ufshcd_wb_probe(struct ufs_hba *hba, const u8 *desc_buf)
 	     (hba->dev_quirks & UFS_DEVICE_QUIRK_SUPPORT_EXTENDED_FEATURES)))
 		goto wb_disabled;
 
-	if (hba->desc_size[QUERY_DESC_IDN_DEVICE] <
-	    DEVICE_DESC_PARAM_EXT_UFS_FEATURE_SUP + 4)
-		goto wb_disabled;
-
 	ext_ufs_feature = get_unaligned_be32(desc_buf +
 					DEVICE_DESC_PARAM_EXT_UFS_FEATURE_SUP);
 
@@ -7850,14 +7803,14 @@ static int ufs_get_device_desc(struct ufs_hba *hba)
 	u8 *desc_buf;
 	struct ufs_dev_info *dev_info = &hba->dev_info;
 
-	desc_buf = kmalloc(QUERY_DESC_MAX_SIZE, GFP_KERNEL);
+	desc_buf = kzalloc(QUERY_DESC_MAX_SIZE, GFP_KERNEL);
 	if (!desc_buf) {
 		err = -ENOMEM;
 		goto out;
 	}
 
 	err = ufshcd_read_desc_param(hba, QUERY_DESC_IDN_DEVICE, 0, 0, desc_buf,
-				     hba->desc_size[QUERY_DESC_IDN_DEVICE]);
+				     QUERY_DESC_MAX_SIZE);
 	if (err) {
 		dev_err(hba->dev, "%s: Failed reading Device Desc. err = %d\n",
 			__func__, err);
@@ -8104,18 +8057,16 @@ static void ufshcd_clear_dbg_ufs_stats(struct ufs_hba *hba)
 static int ufshcd_device_geo_params_init(struct ufs_hba *hba)
 {
 	int err;
-	size_t buff_len;
 	u8 *desc_buf;
 
-	buff_len = hba->desc_size[QUERY_DESC_IDN_GEOMETRY];
-	desc_buf = kmalloc(buff_len, GFP_KERNEL);
+	desc_buf = kzalloc(QUERY_DESC_MAX_SIZE, GFP_KERNEL);
 	if (!desc_buf) {
 		err = -ENOMEM;
 		goto out;
 	}
 
 	err = ufshcd_read_desc_param(hba, QUERY_DESC_IDN_GEOMETRY, 0, 0,
-				     desc_buf, buff_len);
+				     desc_buf, QUERY_DESC_MAX_SIZE);
 	if (err) {
 		dev_err(hba->dev, "%s: Failed reading Geometry Desc. err = %d\n",
 				__func__, err);
@@ -8127,7 +8078,7 @@ 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] >=
+	if (desc_buf[QUERY_DESC_LENGTH_OFFSET] >=
 		GEOMETRY_DESC_PARAM_HPB_MAX_ACTIVE_REGS)
 		ufshpb_get_geo_info(hba, desc_buf);
 
@@ -8212,11 +8163,7 @@ out:
 static int ufshcd_device_params_init(struct ufs_hba *hba)
 {
 	bool flag;
-	int ret, i;
-
-	 /* Init device descriptor sizes */
-	for (i = 0; i < QUERY_DESC_IDN_MAX; i++)
-		hba->desc_size[i] = QUERY_DESC_MAX_SIZE;
+	int ret;
 
 	/* Init UFS geometry descriptor related parameters */
 	ret = ufshcd_device_geo_params_init(hba);