Re: [PATCH v2 3/8] nvmet/fc: Use sgl_alloc() and sgl_free()

[Hannes Reinecke]

On 10/17/2017 12:49 AM, Bart Van Assche wrote:
> Use the sgl_alloc() and sgl_free() functions instead of open coding
> these functions.
> 
> Signed-off-by: Bart Van Assche 
> Reviewed-by: Johannes Thumshirn 
> Cc: Keith Busch 
> Cc: Christoph Hellwig 
> Cc: James Smart 
> Cc: Sagi Grimberg 
> ---
>  drivers/nvme/target/Kconfig |  1 +
>  drivers/nvme/target/fc.c| 36 ++--
>  2 files changed, 3 insertions(+), 34 deletions(-)
> 
Reviewed-by: Hannes Reinecke 

Cheers,

Hannes
-- 
Dr. Hannes ReineckeTeamlead Storage & Networking
h...@suse.de   +49 911 74053 688
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg
GF: F. Imendörffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton
HRB 21284 (AG Nürnberg)

[PATCH v2 3/8] nvmet/fc: Use sgl_alloc() and sgl_free()

[Bart Van Assche]

Use the sgl_alloc() and sgl_free() functions instead of open coding
these functions.

Signed-off-by: Bart Van Assche 
Reviewed-by: Johannes Thumshirn 
Cc: Keith Busch 
Cc: Christoph Hellwig 
Cc: James Smart 
Cc: Sagi Grimberg 
---
 drivers/nvme/target/Kconfig |  1 +
 drivers/nvme/target/fc.c| 36 ++--
 2 files changed, 3 insertions(+), 34 deletions(-)

diff --git a/drivers/nvme/target/Kconfig b/drivers/nvme/target/Kconfig
index 03e4ab65fe77..4d9715630e21 100644
--- a/drivers/nvme/target/Kconfig
+++ b/drivers/nvme/target/Kconfig
@@ -39,6 +39,7 @@ config NVME_TARGET_FC
tristate "NVMe over Fabrics FC target driver"
depends on NVME_TARGET
depends on HAS_DMA
+   select SGL_ALLOC
help
  This enables the NVMe FC target support, which allows exporting NVMe
  devices over FC.
diff --git a/drivers/nvme/target/fc.c b/drivers/nvme/target/fc.c
index 58e010bdda3e..20f96038c272 100644
--- a/drivers/nvme/target/fc.c
+++ b/drivers/nvme/target/fc.c
@@ -1683,31 +1683,12 @@ static int
 nvmet_fc_alloc_tgt_pgs(struct nvmet_fc_fcp_iod *fod)
 {
struct scatterlist *sg;
-   struct page *page;
unsigned int nent;
-   u32 page_len, length;
-   int i = 0;
 
-   length = fod->total_length;
-   nent = DIV_ROUND_UP(length, PAGE_SIZE);
-   sg = kmalloc_array(nent, sizeof(struct scatterlist), GFP_KERNEL);
+   sg = sgl_alloc(fod->total_length, GFP_KERNEL, );
if (!sg)
goto out;
 
-   sg_init_table(sg, nent);
-
-   while (length) {
-   page_len = min_t(u32, length, PAGE_SIZE);
-
-   page = alloc_page(GFP_KERNEL);
-   if (!page)
-   goto out_free_pages;
-
-   sg_set_page([i], page, page_len, 0);
-   length -= page_len;
-   i++;
-   }
-
fod->data_sg = sg;
fod->data_sg_cnt = nent;
fod->data_sg_cnt = fc_dma_map_sg(fod->tgtport->dev, sg, nent,
@@ -1717,14 +1698,6 @@ nvmet_fc_alloc_tgt_pgs(struct nvmet_fc_fcp_iod *fod)
 
return 0;
 
-out_free_pages:
-   while (i > 0) {
-   i--;
-   __free_page(sg_page([i]));
-   }
-   kfree(sg);
-   fod->data_sg = NULL;
-   fod->data_sg_cnt = 0;
 out:
return NVME_SC_INTERNAL;
 }
@@ -1732,18 +1705,13 @@ nvmet_fc_alloc_tgt_pgs(struct nvmet_fc_fcp_iod *fod)
 static void
 nvmet_fc_free_tgt_pgs(struct nvmet_fc_fcp_iod *fod)
 {
-   struct scatterlist *sg;
-   int count;
-
if (!fod->data_sg || !fod->data_sg_cnt)
return;
 
fc_dma_unmap_sg(fod->tgtport->dev, fod->data_sg, fod->data_sg_cnt,
((fod->io_dir == NVMET_FCP_WRITE) ?
DMA_FROM_DEVICE : DMA_TO_DEVICE));
-   for_each_sg(fod->data_sg, sg, fod->data_sg_cnt, count)
-   __free_page(sg_page(sg));
-   kfree(fod->data_sg);
+   sgl_free(fod->data_sg);
fod->data_sg = NULL;
fod->data_sg_cnt = 0;
 }
-- 
2.14.2