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: Christoph Hellwig <hch@xxxxxx> Reviewed-by: Bart Van Assche <bvanassche@xxxxxxx> Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx> --- 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