diff mbox series

[v2,2/2] scsi: ufs: core: Cleanup ufshcd_slave_alloc()

Message ID 20221010092937.520013-3-beanhuo@iokpp.de
State New
Headers show
Series Changes for ufshcd.c | expand

Commit Message

Bean Huo Oct. 10, 2022, 9:29 a.m. UTC 
From: Bean Huo <beanhuo@micron.com>

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 to replace the original twice.

Signed-off-by: Bean Huo <beanhuo@micron.com>
---
 drivers/ufs/core/ufshcd.c | 151 ++++++++++++++------------------------
 1 file changed, 54 insertions(+), 97 deletions(-)

Comments

Bean Huo Oct. 17, 2022, 4:56 p.m. UTC | #1 
Hi Bart,

I took all your suggestions and will send new version patch tomorrow
when the autotest is complete.

thanks,
Bean

On Fri, 2022-10-14 at 14:05 -0700, Bart Van Assche wrote:
> On 10/10/22 02:29, Bean Huo wrote:
> > From: Bean Huo <beanhuo@micron.com>
> > 
> > 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 to replace the original twice.
> 
> The following part can probably be left out from the patch
> description 
> without reducing clarity: " to replace the original twice".
> 
> > +/**
> > + * ufshcd_lu_power_on_wp_init - Initialize LU's power on write
> > protect state
> > + * @hba: per-adapter instance
> > + * @sdev: pointer to SCSI device
> > + * @b_lu_write_protect: bLUWriteProtect value read from LU
> > descriptor
> > + */
> > +static inline void ufshcd_lu_power_on_wp_init(struct ufs_hba *hba,
> > const struct scsi_device *sdev,
> > +                                             u8
> > b_lu_write_protect)
> > +{
> > +       if (hba->dev_info.f_power_on_wp_en && !hba-
> > >dev_info.is_lu_power_on_wp &&
> > +           b_lu_write_protect == UFS_LU_POWER_ON_WP)
> > +               hba->dev_info.is_lu_power_on_wp = true;
> > +}
> 
> The body of this function is only three lines long and this function
> is 
> only called once. Are you sure that you want a separate function
> instead 
> of inlining this function in its only caller?
> 
> > +static void ufshcd_lu_init(struct ufs_hba *hba, struct scsi_device
> > *sdev)
> > +{
> > +       int ret;
> > +       int len;
> > +       u8 lun;
> > +       u8 lun_qdepth;
> > +       u8 *desc_buf;
> 
> Most kernel developers these days order local variable declarations
> from 
> longest to shortest line ("reverse Christmas tree").
> 
> > +       lun_qdepth = hba->nutrs;
> > +       lun = ufshcd_scsi_to_upiu_lun(sdev->lun);
> > +       len = hba->desc_size[QUERY_DESC_IDN_UNIT];
> > +
> > +       desc_buf = kmalloc(len, GFP_KERNEL);
> > +       if (!desc_buf)
> > +               goto set_qdepth;
> > +
> > +       ret = ufshcd_read_unit_desc_param(hba, lun, 0, desc_buf,
> > len);
> > +       if (ret == -EOPNOTSUPP)
> > +               /* If LU doesn't support unit descriptor, its queue
> > depth is set to 1 */
> > +               lun_qdepth = 1;
> > +       else if (desc_buf[UNIT_DESC_PARAM_LU_Q_DEPTH])
> > +               lun_qdepth = min_t(int,
> > desc_buf[UNIT_DESC_PARAM_LU_Q_DEPTH], hba->nutrs);
> 
> ufshcd_read_unit_desc_param() can return fewer bytes than requested.
> How 
> about modifying ufshcd_read_unit_desc_param() such that it returns
> the 
> number of bytes that has been copied and using that return value
> above 
> to check whether at least UNIT_DESC_PARAM_LU_Q_DEPTH bytes have been 
> initialized in desc_buf?
> 
> > +       /*
> > +        * According to UFS device spec, The write protection mode
> > is only supported by normal LU,
> > +        * not supported by WLUN.
> > +        */
> > +       if (!ret && lun < hba->dev_info.max_lu_supported)
> > +               ufshcd_lu_power_on_wp_init(hba, sdev,
> > desc_buf[UNIT_DESC_PARAM_LU_WR_PROTECT]);
> 
> Please insert an if (ret < 0) check after the 
> ufshcd_read_unit_desc_param() call and jump to the kfree() statement
> if 
> ret < 0 instead of checking several times whether or not ret < 0.
> 
> Thanks,
> 
> Bart.
diff mbox series

Patch

diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 7c15cbc737b4..0bf1f99b26bb 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -4862,100 +4862,6 @@  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
@@ -4993,6 +4899,59 @@  static void ufshcd_setup_links(struct ufs_hba *hba, struct scsi_device *sdev)
 	}
 }
 
+/**
+ * ufshcd_lu_power_on_wp_init - Initialize LU's power on write protect state
+ * @hba: per-adapter instance
+ * @sdev: pointer to SCSI device
+ * @b_lu_write_protect: bLUWriteProtect value read from LU descriptor
+ */
+static inline void ufshcd_lu_power_on_wp_init(struct ufs_hba *hba, const struct scsi_device *sdev,
+					      u8 b_lu_write_protect)
+{
+	if (hba->dev_info.f_power_on_wp_en && !hba->dev_info.is_lu_power_on_wp &&
+	    b_lu_write_protect == UFS_LU_POWER_ON_WP)
+		hba->dev_info.is_lu_power_on_wp = true;
+}
+
+static void ufshcd_lu_init(struct ufs_hba *hba, struct scsi_device *sdev)
+{
+	int ret;
+	int len;
+	u8 lun;
+	u8 lun_qdepth;
+	u8 *desc_buf;
+
+	lun_qdepth = hba->nutrs;
+	lun = ufshcd_scsi_to_upiu_lun(sdev->lun);
+	len = hba->desc_size[QUERY_DESC_IDN_UNIT];
+
+	desc_buf = kmalloc(len, GFP_KERNEL);
+	if (!desc_buf)
+		goto set_qdepth;
+
+	ret = ufshcd_read_unit_desc_param(hba, lun, 0, desc_buf, len);
+	if (ret == -EOPNOTSUPP)
+		/* If LU doesn't support unit descriptor, its queue depth is set to 1 */
+		lun_qdepth = 1;
+	else if (desc_buf[UNIT_DESC_PARAM_LU_Q_DEPTH])
+		lun_qdepth = min_t(int, desc_buf[UNIT_DESC_PARAM_LU_Q_DEPTH], hba->nutrs);
+	/*
+	 * According to UFS device spec, The write protection mode is only supported by normal LU,
+	 * not supported by WLUN.
+	 */
+	if (!ret && lun < hba->dev_info.max_lu_supported)
+		ufshcd_lu_power_on_wp_init(hba, sdev, desc_buf[UNIT_DESC_PARAM_LU_WR_PROTECT]);
+
+	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
@@ -5020,9 +4979,7 @@  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);