[PATCH v4 2/3] scsi: ufs: core: Cleanup ufshcd_slave_alloc()

From: Bean Huo
Date: Sat Oct 22 2022 - 17:37:21 EST


From: Bean Huo <beanhuo@xxxxxxxxxx>

Combine ufshcd_get_lu_power_on_wp_status() and ufshcd_set_queue_depth()
into one single ufshcd_lu_init(), so that we only need to read the LUN
descriptor once.

Signed-off-by: Bean Huo <beanhuo@xxxxxxxxxx>
---
drivers/ufs/core/ufshcd.c | 150 ++++++++++++++------------------------
1 file changed, 53 insertions(+), 97 deletions(-)

diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 8cdba9a54870..8599780022fb 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -4859,100 +4859,6 @@ static int ufshcd_verify_dev_init(struct ufs_hba *hba)
return err;
}

-/**
- * ufshcd_set_queue_depth - set lun queue depth
- * @sdev: pointer to SCSI device
- *
- * Read bLUQueueDepth value and activate scsi tagged command
- * queueing. For WLUN, queue depth is set to 1. For best-effort
- * cases (bLUQueueDepth = 0) the queue depth is set to a maximum
- * value that host can queue.
- */
-static void ufshcd_set_queue_depth(struct scsi_device *sdev)
-{
- int ret = 0;
- u8 lun_qdepth;
- struct ufs_hba *hba;
-
- hba = shost_priv(sdev->host);
-
- lun_qdepth = hba->nutrs;
- ret = ufshcd_read_unit_desc_param(hba,
- ufshcd_scsi_to_upiu_lun(sdev->lun),
- UNIT_DESC_PARAM_LU_Q_DEPTH,
- &lun_qdepth,
- sizeof(lun_qdepth));
-
- /* Some WLUN doesn't support unit descriptor */
- if (ret == -EOPNOTSUPP)
- lun_qdepth = 1;
- else if (!lun_qdepth)
- /* eventually, we can figure out the real queue depth */
- lun_qdepth = hba->nutrs;
- else
- lun_qdepth = min_t(int, lun_qdepth, hba->nutrs);
-
- dev_dbg(hba->dev, "%s: activate tcq with queue depth %d\n",
- __func__, lun_qdepth);
- scsi_change_queue_depth(sdev, lun_qdepth);
-}
-
-/*
- * ufshcd_get_lu_wp - returns the "b_lu_write_protect" from UNIT DESCRIPTOR
- * @hba: per-adapter instance
- * @lun: UFS device lun id
- * @b_lu_write_protect: pointer to buffer to hold the LU's write protect info
- *
- * Returns 0 in case of success and b_lu_write_protect status would be returned
- * @b_lu_write_protect parameter.
- * Returns -ENOTSUPP if reading b_lu_write_protect is not supported.
- * Returns -EINVAL in case of invalid parameters passed to this function.
- */
-static int ufshcd_get_lu_wp(struct ufs_hba *hba,
- u8 lun,
- u8 *b_lu_write_protect)
-{
- int ret;
-
- if (!b_lu_write_protect)
- ret = -EINVAL;
- /*
- * According to UFS device spec, RPMB LU can't be write
- * protected so skip reading bLUWriteProtect parameter for
- * it. For other W-LUs, UNIT DESCRIPTOR is not available.
- */
- else if (lun >= hba->dev_info.max_lu_supported)
- ret = -ENOTSUPP;
- else
- ret = ufshcd_read_unit_desc_param(hba,
- lun,
- UNIT_DESC_PARAM_LU_WR_PROTECT,
- b_lu_write_protect,
- sizeof(*b_lu_write_protect));
- return ret;
-}
-
-/**
- * ufshcd_get_lu_power_on_wp_status - get LU's power on write protect
- * status
- * @hba: per-adapter instance
- * @sdev: pointer to SCSI device
- *
- */
-static inline void ufshcd_get_lu_power_on_wp_status(struct ufs_hba *hba,
- const struct scsi_device *sdev)
-{
- if (hba->dev_info.f_power_on_wp_en &&
- !hba->dev_info.is_lu_power_on_wp) {
- u8 b_lu_write_protect;
-
- if (!ufshcd_get_lu_wp(hba, ufshcd_scsi_to_upiu_lun(sdev->lun),
- &b_lu_write_protect) &&
- (b_lu_write_protect == UFS_LU_POWER_ON_WP))
- hba->dev_info.is_lu_power_on_wp = true;
- }
-}
-
/**
* ufshcd_setup_links - associate link b/w device wlun and other luns
* @sdev: pointer to SCSI device
@@ -4990,6 +4896,58 @@ static void ufshcd_setup_links(struct ufs_hba *hba, struct scsi_device *sdev)
}
}

+/**
+ * ufshcd_lu_init - Initialize the relevant parameters of the LU
+ * @hba: per-adapter instance
+ * @sdev: pointer to SCSI device
+ */
+static void ufshcd_lu_init(struct ufs_hba *hba, struct scsi_device *sdev)
+{
+ int len = hba->desc_size[QUERY_DESC_IDN_UNIT];
+ u8 lun = ufshcd_scsi_to_upiu_lun(sdev->lun);
+ u8 lun_qdepth = hba->nutrs;
+ u8 *desc_buf;
+ int ret;
+
+ desc_buf = kzalloc(len, GFP_KERNEL);
+ if (!desc_buf)
+ goto set_qdepth;
+
+ ret = ufshcd_read_unit_desc_param(hba, lun, 0, desc_buf, len);
+ if (ret < 0) {
+ if (ret == -EOPNOTSUPP)
+ /* If LU doesn't support unit descriptor, its queue depth is set to 1 */
+ lun_qdepth = 1;
+ kfree(desc_buf);
+ goto set_qdepth;
+ }
+
+ if (desc_buf[UNIT_DESC_PARAM_LU_Q_DEPTH]) {
+ /*
+ * In per-LU queueing architecture, bLUQueueDepth will not be 0, then we will
+ * use the smaller between UFSHCI CAP.NUTRS and UFS LU bLUQueueDepth
+ */
+ lun_qdepth = min_t(int, desc_buf[UNIT_DESC_PARAM_LU_Q_DEPTH], hba->nutrs);
+ }
+ /*
+ * According to UFS device specification, the write protection mode is only supported by
+ * normal LU, not supported by WLUN.
+ */
+ if (hba->dev_info.f_power_on_wp_en && lun < hba->dev_info.max_lu_supported &&
+ !hba->dev_info.is_lu_power_on_wp &&
+ desc_buf[UNIT_DESC_PARAM_LU_WR_PROTECT] == UFS_LU_POWER_ON_WP)
+ hba->dev_info.is_lu_power_on_wp = true;
+
+ kfree(desc_buf);
+set_qdepth:
+ /*
+ * For WLUNs that don't support unit descriptor, queue depth is set to 1. For LUs whose
+ * bLUQueueDepth == 0, the queue depth is set to a maximum value that host can queue.
+ */
+ dev_dbg(hba->dev, "Set LU %x queue depth %d\n", lun, lun_qdepth);
+ scsi_change_queue_depth(sdev, lun_qdepth);
+}
+
/**
* ufshcd_slave_alloc - handle initial SCSI device configurations
* @sdev: pointer to SCSI device
@@ -5017,9 +4975,7 @@ static int ufshcd_slave_alloc(struct scsi_device *sdev)
/* WRITE_SAME command is not supported */
sdev->no_write_same = 1;

- ufshcd_set_queue_depth(sdev);
-
- ufshcd_get_lu_power_on_wp_status(hba, sdev);
+ ufshcd_lu_init(hba, sdev);

ufshcd_setup_links(hba, sdev);

--
2.34.1