[PATCH 0/3] Use sgl_alloc_order() and sgl_free_order()

[PATCH 0/3] Use sgl_alloc_order() and sgl_free_order()

[Bart Van Assche]

Hello Martin,

In kernel v4.16-rc1 the functions sgl_alloc_order() and sgl_free_order() were
introduced in lib/scatterlist.c. This patch series introduces these functions
in the ipr and pmcraid SCSI drivers. Please consider these patches for kernel
v4.17.

Thanks,

Bart.

Bart Van Assche (3):
  scsi/ipr: Use sgl_alloc_order() and sgl_free_order()
  scsi/pmcraid: Remove an unused structure member
  scsi/pmcraid: Use sgl_alloc_order() and sgl_free_order()

 drivers/scsi/Kconfig   |  2 ++
 drivers/scsi/ipr.c     | 49 ++++++++-----------------------------------------
 drivers/scsi/ipr.h     |  2 +-
 drivers/scsi/pmcraid.c | 43 ++++---------------------------------------
 drivers/scsi/pmcraid.h |  3 +--
 5 files changed, 16 insertions(+), 83 deletions(-)

-- 
2.16.1

[PATCH 1/3] scsi/ipr: Use sgl_alloc_order() and sgl_free_order()

[Bart Van Assche]

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>
Acked-by: Brian King <brking@linux.vnet.ibm.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: linux-scsi@vger.kernel.org
---
 drivers/scsi/Kconfig |  1 +
 drivers/scsi/ipr.c   | 49 ++++++++-----------------------------------------
 drivers/scsi/ipr.h   |  2 +-
 3 files changed, 10 insertions(+), 42 deletions(-)

diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig
index 8a739b74cfb7..7e3f6e37fb66 100644
--- a/drivers/scsi/Kconfig
+++ b/drivers/scsi/Kconfig
@@ -1059,6 +1059,7 @@ config SCSI_IPR
 	depends on PCI && SCSI && ATA
 	select FW_LOADER
 	select IRQ_POLL
+	select SGL_ALLOC
 	---help---
 	  This driver supports the IBM Power Linux family RAID adapters.
 	  This includes IBM pSeries 5712, 5703, 5709, and 570A, as well
diff --git a/drivers/scsi/ipr.c b/drivers/scsi/ipr.c
index e07dd990e585..52735162444f 100644
--- a/drivers/scsi/ipr.c
+++ b/drivers/scsi/ipr.c
@@ -3816,10 +3816,8 @@ static struct device_attribute ipr_iopoll_weight_attr = {
  **/
 static struct ipr_sglist *ipr_alloc_ucode_buffer(int buf_len)
 {
-	int sg_size, order, bsize_elem, num_elem, i, j;
+	int sg_size, order;
 	struct ipr_sglist *sglist;
-	struct scatterlist *scatterlist;
-	struct page *page;
 
 	/* Get the minimum size per scatter/gather element */
 	sg_size = buf_len / (IPR_MAX_SGLIST - 1);
@@ -3827,45 +3825,18 @@ static struct ipr_sglist *ipr_alloc_ucode_buffer(int buf_len)
 	/* Get the actual size per element */
 	order = get_order(sg_size);
 
-	/* Determine the actual number of bytes per element */
-	bsize_elem = PAGE_SIZE * (1 << order);
-
-	/* Determine the actual number of sg entries needed */
-	if (buf_len % bsize_elem)
-		num_elem = (buf_len / bsize_elem) + 1;
-	else
-		num_elem = buf_len / bsize_elem;
-
 	/* Allocate a scatter/gather list for the DMA */
-	sglist = kzalloc(sizeof(struct ipr_sglist) +
-			 (sizeof(struct scatterlist) * (num_elem - 1)),
-			 GFP_KERNEL);
-
+	sglist = kzalloc(sizeof(struct ipr_sglist), GFP_KERNEL);
 	if (sglist == NULL) {
 		ipr_trace;
 		return NULL;
 	}
-
-	scatterlist = sglist->scatterlist;
-	sg_init_table(scatterlist, num_elem);
-
 	sglist->order = order;
-	sglist->num_sg = num_elem;
-
-	/* Allocate a bunch of sg elements */
-	for (i = 0; i < num_elem; i++) {
-		page = alloc_pages(GFP_KERNEL, order);
-		if (!page) {
-			ipr_trace;
-
-			/* Free up what we already allocated */
-			for (j = i - 1; j >= 0; j--)
-				__free_pages(sg_page(&scatterlist[j]), order);
-			kfree(sglist);
-			return NULL;
-		}
-
-		sg_set_page(&scatterlist[i], page, 0, 0);
+	sglist->scatterlist = sgl_alloc_order(buf_len, order, false, GFP_KERNEL,
+					      &sglist->num_sg);
+	if (!sglist->scatterlist) {
+		kfree(sglist);
+		return NULL;
 	}
 
 	return sglist;
@@ -3883,11 +3854,7 @@ static struct ipr_sglist *ipr_alloc_ucode_buffer(int buf_len)
  **/
 static void ipr_free_ucode_buffer(struct ipr_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);
 }
 
diff --git a/drivers/scsi/ipr.h b/drivers/scsi/ipr.h
index c7f0e9e3cd7d..93570734cbfb 100644
--- a/drivers/scsi/ipr.h
+++ b/drivers/scsi/ipr.h
@@ -1454,7 +1454,7 @@ struct ipr_sglist {
 	u32 num_sg;
 	u32 num_dma_sg;
 	u32 buffer_len;
-	struct scatterlist scatterlist[1];
+	struct scatterlist *scatterlist;
 };
 
 enum ipr_sdt_state {
-- 
2.16.1

[PATCH 2/3] scsi/pmcraid: Remove an unused structure member

[Bart Van Assche]

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>
---
 drivers/scsi/pmcraid.h | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/scsi/pmcraid.h b/drivers/scsi/pmcraid.h
index 8bfac72a242b..44da91712115 100644
--- a/drivers/scsi/pmcraid.h
+++ b/drivers/scsi/pmcraid.h
@@ -542,7 +542,6 @@ struct pmcraid_sglist {
 	u32 order;
 	u32 num_sg;
 	u32 num_dma_sg;
-	u32 buffer_len;
 	struct scatterlist scatterlist[1];
 };
 
-- 
2.16.1

[PATCH 3/3] scsi/pmcraid: Use sgl_alloc_order() and sgl_free_order()

[Bart Van Assche]

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>
---
 drivers/scsi/Kconfig   |  1 +
 drivers/scsi/pmcraid.c | 43 ++++---------------------------------------
 drivers/scsi/pmcraid.h |  2 +-
 3 files changed, 6 insertions(+), 40 deletions(-)

diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig
index 7e3f6e37fb66..8647ca9199b3 100644
--- a/drivers/scsi/Kconfig
+++ b/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.
 
diff --git a/drivers/scsi/pmcraid.c b/drivers/scsi/pmcraid.c
index 201c8de1853d..2fcecd8c9346 100644
--- a/drivers/scsi/pmcraid.c
+++ b/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;
 }
diff --git a/drivers/scsi/pmcraid.h b/drivers/scsi/pmcraid.h
index 44da91712115..754ef30927e2 100644
--- a/drivers/scsi/pmcraid.h
+++ b/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 */
-- 
2.16.1

Re: [PATCH 0/3] Use sgl_alloc_order() and sgl_free_order()

[Martin K. Petersen]

Bart,

> In kernel v4.16-rc1 the functions sgl_alloc_order() and
> sgl_free_order() were introduced in lib/scatterlist.c. This patch
> series introduces these functions in the ipr and pmcraid SCSI
> drivers. Please consider these patches for kernel v4.17.

Applied to 4.17/scsi-queue, thanks!

-- 
Martin K. Petersen	Oracle Linux Engineering