scsi: pmcraid: Use sgl_alloc_order() and sgl_free_order()

Use the sgl_alloc_order() and sgl_free_order() functions instead of open
coding these functions.
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Cc: Anil Ravindranath <anil_ravindranath@pmc-sierra.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/Kconfig

@@ -1577,6 +1577,7 @@ config ZFCP
 config SCSI_PMCRAID
 	tristate "PMC SIERRA Linux MaxRAID adapter support"
 	depends on PCI && SCSI && NET
+	select SGL_ALLOC
 	---help---
 	  This driver supports the PMC SIERRA MaxRAID adapters.
 

drivers/scsi/pmcraid.c

@@ -3225,12 +3225,7 @@ static int pmcraid_build_ioadl(
  */
 static void pmcraid_free_sglist(struct pmcraid_sglist *sglist)
 {
-	int i;
-
-	for (i = 0; i < sglist->num_sg; i++)
-		__free_pages(sg_page(&(sglist->scatterlist[i])),
-			     sglist->order);
-
+	sgl_free_order(sglist->scatterlist, sglist->order);
 	kfree(sglist);
 }
 
@@ -3247,50 +3242,20 @@ static void pmcraid_free_sglist(struct pmcraid_sglist *sglist)
 static struct pmcraid_sglist *pmcraid_alloc_sglist(int buflen)
 {
 	struct pmcraid_sglist *sglist;
-	struct scatterlist *scatterlist;
-	struct page *page;
-	int num_elem, i, j;
 	int sg_size;
 	int order;
-	int bsize_elem;
 
 	sg_size = buflen / (PMCRAID_MAX_IOADLS - 1);
 	order = (sg_size > 0) ? get_order(sg_size) : 0;
-	bsize_elem = PAGE_SIZE * (1 << order);
-
-	/* Determine the actual number of sg entries needed */
-	if (buflen % bsize_elem)
-		num_elem = (buflen / bsize_elem) + 1;
-	else
-		num_elem = buflen / bsize_elem;
 
 	/* Allocate a scatter/gather list for the DMA */
-	sglist = kzalloc(sizeof(struct pmcraid_sglist) +
-			 (sizeof(struct scatterlist) * (num_elem - 1)),
-			 GFP_KERNEL);
-
+	sglist = kzalloc(sizeof(struct pmcraid_sglist), GFP_KERNEL);
 	if (sglist == NULL)
 		return NULL;
 
-	scatterlist = sglist->scatterlist;
-	sg_init_table(scatterlist, num_elem);
 	sglist->order = order;
-	sglist->num_sg = num_elem;
-	sg_size = buflen;
-
-	for (i = 0; i < num_elem; i++) {
-		page = alloc_pages(GFP_KERNEL|GFP_DMA|__GFP_ZERO, order);
-		if (!page) {
-			for (j = i - 1; j >= 0; j--)
-				__free_pages(sg_page(&scatterlist[j]), order);
-			kfree(sglist);
-			return NULL;
-		}
-
-		sg_set_page(&scatterlist[i], page,
-			sg_size < bsize_elem ? sg_size : bsize_elem, 0);
-		sg_size -= bsize_elem;
-	}
+	sgl_alloc_order(buflen, order, false,
+			GFP_KERNEL | GFP_DMA | __GFP_ZERO, &sglist->num_sg);
 
 	return sglist;
 }

drivers/scsi/pmcraid.h

@@ -542,7 +542,7 @@ struct pmcraid_sglist {
 	u32 order;
 	u32 num_sg;
 	u32 num_dma_sg;
-	struct scatterlist scatterlist[1];
+	struct scatterlist *scatterlist;
 };
 
 /* page D0 inquiry data of focal point resource */