[PATCH V4 06/16] scsi: pmcraid: use sg helper to operate scatterlist
Ming Lei
ming.lei at redhat.com
Mon Jun 17 03:03:39 UTC 2019
Use the scatterlist iterators and remove direct indexing of the
scatterlist array.
This way allows us to pre-allocate one small scatterlist, which can be
chained with one runtime allocated scatterlist if the pre-allocated one
isn't enough for the whole request.
Signed-off-by: Ming Lei <ming.lei at redhat.com>
---
drivers/scsi/pmcraid.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/drivers/scsi/pmcraid.c b/drivers/scsi/pmcraid.c
index e338d7a4f571..286cac59cb5f 100644
--- a/drivers/scsi/pmcraid.c
+++ b/drivers/scsi/pmcraid.c
@@ -3270,7 +3270,7 @@ static int pmcraid_copy_sglist(
int direction
)
{
- struct scatterlist *scatterlist;
+ struct scatterlist *sg;
void *kaddr;
int bsize_elem;
int i;
@@ -3279,10 +3279,10 @@ static int pmcraid_copy_sglist(
/* Determine the actual number of bytes per element */
bsize_elem = PAGE_SIZE * (1 << sglist->order);
- scatterlist = sglist->scatterlist;
+ sg = sglist->scatterlist;
- for (i = 0; i < (len / bsize_elem); i++, buffer += bsize_elem) {
- struct page *page = sg_page(&scatterlist[i]);
+ for (i = 0; i < (len / bsize_elem); i++, sg = sg_next(sg), buffer += bsize_elem) {
+ struct page *page = sg_page(sg);
kaddr = kmap(page);
if (direction == DMA_TO_DEVICE)
@@ -3297,11 +3297,11 @@ static int pmcraid_copy_sglist(
return -EFAULT;
}
- scatterlist[i].length = bsize_elem;
+ sg->length = bsize_elem;
}
if (len % bsize_elem) {
- struct page *page = sg_page(&scatterlist[i]);
+ struct page *page = sg_page(sg);
kaddr = kmap(page);
@@ -3312,7 +3312,7 @@ static int pmcraid_copy_sglist(
kunmap(page);
- scatterlist[i].length = len % bsize_elem;
+ sg->length = len % bsize_elem;
}
if (rc) {
--
2.20.1
More information about the devel
mailing list