[SCSI] ide-scsi: remove usage of sg_last()
We want to remove sg_last(), it's a very expensive interface. So
keep track of number of sg entries in the sg list, instead of comparing
with the last entry.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/drivers/scsi/ide-scsi.c b/drivers/scsi/ide-scsi.c
index bd74f6c..fa7ba64 100644
--- a/drivers/scsi/ide-scsi.c
+++ b/drivers/scsi/ide-scsi.c
@@ -70,7 +70,7 @@
u8 *buffer; /* Data buffer */
u8 *current_position; /* Pointer into the above buffer */
struct scatterlist *sg; /* Scatter gather table */
- struct scatterlist *last_sg; /* Last sg element */
+ unsigned int sg_cnt; /* Number of entries in sg */
int b_count; /* Bytes transferred from current entry */
struct scsi_cmnd *scsi_cmd; /* SCSI command */
void (*done)(struct scsi_cmnd *); /* Scsi completion routine */
@@ -192,7 +192,7 @@
}
bcount -= count; pc->b_count += count;
if (pc->b_count == pc->sg->length) {
- if (pc->sg == pc->last_sg)
+ if (!--pc->sg_cnt)
break;
pc->sg = sg_next(pc->sg);
pc->b_count = 0;
@@ -229,7 +229,7 @@
}
bcount -= count; pc->b_count += count;
if (pc->b_count == pc->sg->length) {
- if (pc->sg == pc->last_sg)
+ if (!--pc->sg_cnt)
break;
pc->sg = sg_next(pc->sg);
pc->b_count = 0;
@@ -807,7 +807,7 @@
memcpy (pc->c, cmd->cmnd, cmd->cmd_len);
pc->buffer = NULL;
pc->sg = scsi_sglist(cmd);
- pc->last_sg = sg_last(pc->sg, scsi_sg_count(cmd));
+ pc->sg_cnt = scsi_sg_count(cmd);
pc->b_count = 0;
pc->request_transfer = pc->buffer_size = scsi_bufflen(cmd);
pc->scsi_cmd = cmd;