[PATCH v8 6/7] scsi: libiscsi: use sendpage_ok() in iscsi_tcp_segment_map()

From: Coly Li
Date: Fri Sep 25 2020 - 11:02:19 EST


In iscsci driver, iscsi_tcp_segment_map() uses the following code to
check whether the page should or not be handled by sendpage:
if (!recv && page_count(sg_page(sg)) >= 1 && !PageSlab(sg_page(sg)))

The "page_count(sg_page(sg)) >= 1 && !PageSlab(sg_page(sg)" part is to
make sure the page can be sent to network layer's zero copy path. This
part is exactly what sendpage_ok() does.

This patch uses use sendpage_ok() in iscsi_tcp_segment_map() to replace
the original open coded checks.

Signed-off-by: Coly Li <colyli@xxxxxxx>
Cc: Vasily Averin <vvs@xxxxxxxxxxxxx>
Cc: Cong Wang <amwang@xxxxxxxxxx>
Cc: Mike Christie <michaelc@xxxxxxxxxxx>
Cc: Lee Duncan <lduncan@xxxxxxxx>
Cc: Chris Leech <cleech@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Hannes Reinecke <hare@xxxxxxx>
---
drivers/scsi/libiscsi_tcp.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/scsi/libiscsi_tcp.c b/drivers/scsi/libiscsi_tcp.c
index 37e5d4e48c2f..83f14b2c8804 100644
--- a/drivers/scsi/libiscsi_tcp.c
+++ b/drivers/scsi/libiscsi_tcp.c
@@ -128,7 +128,7 @@ static void iscsi_tcp_segment_map(struct iscsi_segment *segment, int recv)
* coalescing neighboring slab objects into a single frag which
* triggers one of hardened usercopy checks.
*/
- if (!recv && page_count(sg_page(sg)) >= 1 && !PageSlab(sg_page(sg)))
+ if (!recv && sendpage_ok(sg_page(sg)))
return;

if (recv) {
--
2.26.2