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.
Reviewed-by: Bart Van Assche <bvanassche@xxxxxxx>
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
---
drivers/scsi/ipr.c | 29 ++++++++++++++++-------------
1 file changed, 16 insertions(+), 13 deletions(-)
diff --git a/drivers/scsi/ipr.c b/drivers/scsi/ipr.c
index 6d053e220153..bf17540affbc 100644
--- a/drivers/scsi/ipr.c
+++ b/drivers/scsi/ipr.c
@@ -3915,22 +3915,23 @@ static int ipr_copy_ucode_buffer(struct ipr_sglist *sglist,
u8 *buffer, u32 len)
{
int bsize_elem, i, result = 0;
- struct scatterlist *scatterlist;
+ struct scatterlist *sg;
void *kaddr;
/* 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);
memcpy(kaddr, buffer, bsize_elem);
kunmap(page);
- scatterlist[i].length = bsize_elem;
+ sg->length = bsize_elem;
if (result != 0) {
ipr_trace;
@@ -3939,13 +3940,13 @@ static int ipr_copy_ucode_buffer(struct ipr_sglist *sglist,
}
if (len % bsize_elem) {
- struct page *page = sg_page(&scatterlist[i]);
+ struct page *page = sg_page(sg);
kaddr = kmap(page);
memcpy(kaddr, buffer, len % bsize_elem);
kunmap(page);
- scatterlist[i].length = len % bsize_elem;
+ sg->length = len % bsize_elem;
}
sglist->buffer_len = len;
@@ -3966,6 +3967,7 @@ static void ipr_build_ucode_ioadl64(struct ipr_cmnd *ipr_cmd,
struct ipr_ioarcb *ioarcb = &ipr_cmd->ioarcb;
struct ipr_ioadl64_desc *ioadl64 = ipr_cmd->i.ioadl64;
struct scatterlist *scatterlist = sglist->scatterlist;
+ struct scatterlist *sg;
int i;
ipr_cmd->dma_use_sg = sglist->num_dma_sg;
@@ -3974,10 +3976,10 @@ static void ipr_build_ucode_ioadl64(struct ipr_cmnd *ipr_cmd,
ioarcb->ioadl_len =
cpu_to_be32(sizeof(struct ipr_ioadl64_desc) * ipr_cmd->dma_use_sg);
- for (i = 0; i < ipr_cmd->dma_use_sg; i++) {
+ for_each_sg(scatterlist, sg, ipr_cmd->dma_use_sg, i) {
ioadl64[i].flags = cpu_to_be32(IPR_IOADL_FLAGS_WRITE);
- ioadl64[i].data_len = cpu_to_be32(sg_dma_len(&scatterlist[i]));
- ioadl64[i].address = cpu_to_be64(sg_dma_address(&scatterlist[i]));
+ ioadl64[i].data_len = cpu_to_be32(sg_dma_len(sg));
+ ioadl64[i].address = cpu_to_be64(sg_dma_address(sg));
}
ioadl64[i-1].flags |= cpu_to_be32(IPR_IOADL_FLAGS_LAST);
@@ -3997,6 +3999,7 @@ static void ipr_build_ucode_ioadl(struct ipr_cmnd *ipr_cmd,
struct ipr_ioarcb *ioarcb = &ipr_cmd->ioarcb;
struct ipr_ioadl_desc *ioadl = ipr_cmd->i.ioadl;
struct scatterlist *scatterlist = sglist->scatterlist;
+ struct scatterlist *sg;
int i;
ipr_cmd->dma_use_sg = sglist->num_dma_sg;
@@ -4006,11 +4009,11 @@ static void ipr_build_ucode_ioadl(struct ipr_cmnd *ipr_cmd,
ioarcb->ioadl_len =
cpu_to_be32(sizeof(struct ipr_ioadl_desc) * ipr_cmd->dma_use_sg);
- for (i = 0; i < ipr_cmd->dma_use_sg; i++) {
+ for_each_sg(scatterlist, sg, ipr_cmd->dma_use_sg, i) {
ioadl[i].flags_and_data_len =
- cpu_to_be32(IPR_IOADL_FLAGS_WRITE | sg_dma_len(&scatterlist[i]));
+ cpu_to_be32(IPR_IOADL_FLAGS_WRITE | sg_dma_len(sg));
ioadl[i].address =
- cpu_to_be32(sg_dma_address(&scatterlist[i]));
+ cpu_to_be32(sg_dma_address(sg));
}
ioadl[i-1].flags_and_data_len |=
--
2.20.1
