[PATCH v3 4/7] ufs: core: Split ufshcd_map_sg

Bean Huo
2022-12-01T14:05:02Z

Take out the "map scatter-gather list to prdt" part of the code in
ufshcd_map_sg and split it into a new function ufshcd_sgl_to_prdt.

Signed-off-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Avri Altman <avri.altman@wdc.com>
---
drivers/ufs/core/ufshcd.c | 48 +++++++++++++++++++++++----------------
1 file changed, 29 insertions(+), 19 deletions(-)

diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 2dbe24977822..d1bcb4c4e4e4 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -2399,38 +2399,30 @@ int ufshcd_send_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd)
}

/**
- * ufshcd_map_sg - Map scatter-gather list to prdt
- * @hba: per adapter instance
- * @lrbp: pointer to local reference block
- *
- * Returns 0 in case of success, non-zero value in case of failure
+ * ufshcd_sgl_to_prdt - SG list to PRTD (Physical Region Description Table, 4DW format)
+ * @hba: per-adapter instance
+ * @lrbp: pointer to local reference block
+ * @sg_entries: The number of sg lists actually used
+ * @sg_list: Pointer to SG list
*/
-static int ufshcd_map_sg(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
+static void ufshcd_sgl_to_prdt(struct ufs_hba *hba, struct ufshcd_lrb *lrbp, int sg_entries,
+ struct scatterlist *sg_list)
{
struct ufshcd_sg_entry *prd_table;
struct scatterlist *sg;
- struct scsi_cmnd *cmd;
- int sg_segments;
int i;

- cmd = lrbp->cmd;
- sg_segments = scsi_dma_map(cmd);
- if (sg_segments < 0)
- return sg_segments;
-
- if (sg_segments) {
+ if (sg_entries) {

if (hba->quirks & UFSHCD_QUIRK_PRDT_BYTE_GRAN)
lrbp->utr_descriptor_ptr->prd_table_length =
- cpu_to_le16((sg_segments *
- sizeof(struct ufshcd_sg_entry)));
+ cpu_to_le16((sg_entries * sizeof(struct ufshcd_sg_entry)));
else
- lrbp->utr_descriptor_ptr->prd_table_length =
- cpu_to_le16(sg_segments);
+ lrbp->utr_descriptor_ptr->prd_table_length = cpu_to_le16(sg_entries);

prd_table = lrbp->ucd_prdt_ptr;

- scsi_for_each_sg(cmd, sg, sg_segments, i) {
+ for_each_sg(sg_list, sg, sg_entries, i) {
const unsigned int len = sg_dma_len(sg);

/*
@@ -2449,6 +2441,24 @@ static int ufshcd_map_sg(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
} else {
lrbp->utr_descriptor_ptr->prd_table_length = 0;
}
+}
+
+/**
+ * ufshcd_map_sg - Map scatter-gather list to prdt
+ * @hba: per adapter instance
+ * @lrbp: pointer to local reference block
+ *
+ * Returns 0 in case of success, non-zero value in case of failure
+ */
+static int ufshcd_map_sg(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
+{
+ struct scsi_cmnd *cmd = lrbp->cmd;
+ int sg_segments = scsi_dma_map(cmd);
+
+ if (sg_segments < 0)
+ return sg_segments;
+
+ ufshcd_sgl_to_prdt(hba, lrbp, sg_segments, scsi_sglist(cmd));

return 0;
}
--
2.25.1