[PATCH net-next v9 7/8] netdevsim: use netmem descriptor and APIs for page pool

[Byungchul Park <byungchul@sk.com>]

To simplify struct page, the effort to separate its own descriptor from
struct page is required and the work for page pool is on going.

Use netmem descriptor and APIs for page pool in netdevsim code.

Signed-off-by: Byungchul Park <byungchul@sk.com>
---
 drivers/net/netdevsim/netdev.c    | 19 ++++++++++---------
 drivers/net/netdevsim/netdevsim.h |  2 +-
 2 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/drivers/net/netdevsim/netdev.c b/drivers/net/netdevsim/netdev.c
index e36d3e846c2d..ba19870524c5 100644
--- a/drivers/net/netdevsim/netdev.c
+++ b/drivers/net/netdevsim/netdev.c
@@ -812,7 +812,7 @@ nsim_pp_hold_read(struct file *file, char __user *data,
 	struct netdevsim *ns = file->private_data;
 	char buf[3] = "n\n";
 
-	if (ns->page)
+	if (ns->netmem)
 		buf[0] = 'y';
 
 	return simple_read_from_buffer(data, count, ppos, buf, 2);
@@ -832,18 +832,19 @@ nsim_pp_hold_write(struct file *file, const char __user *data,
 
 	rtnl_lock();
 	ret = count;
-	if (val == !!ns->page)
+	if (val == !!ns->netmem)
 		goto exit;
 
 	if (!netif_running(ns->netdev) && val) {
 		ret = -ENETDOWN;
 	} else if (val) {
-		ns->page = page_pool_dev_alloc_pages(ns->rq[0]->page_pool);
-		if (!ns->page)
+		ns->netmem = page_pool_alloc_netmems(ns->rq[0]->page_pool,
+						     GFP_ATOMIC | __GFP_NOWARN);
+		if (!ns->netmem)
 			ret = -ENOMEM;
 	} else {
-		page_pool_put_full_page(ns->page->pp, ns->page, false);
-		ns->page = NULL;
+		page_pool_put_full_netmem(netmem_get_pp(ns->netmem), ns->netmem, false);
+		ns->netmem = 0;
 	}
 
 exit:
@@ -1068,9 +1069,9 @@ void nsim_destroy(struct netdevsim *ns)
 		nsim_exit_netdevsim(ns);
 
 	/* Put this intentionally late to exercise the orphaning path */
-	if (ns->page) {
-		page_pool_put_full_page(ns->page->pp, ns->page, false);
-		ns->page = NULL;
+	if (ns->netmem) {
+		page_pool_put_full_netmem(netmem_get_pp(ns->netmem), ns->netmem, false);
+		ns->netmem = 0;
 	}
 
 	free_netdev(dev);
diff --git a/drivers/net/netdevsim/netdevsim.h b/drivers/net/netdevsim/netdevsim.h
index 809dd29fc5fe..129e005ef577 100644
--- a/drivers/net/netdevsim/netdevsim.h
+++ b/drivers/net/netdevsim/netdevsim.h
@@ -132,7 +132,7 @@ struct netdevsim {
 		struct debugfs_u32_array dfs_ports[2];
 	} udp_ports;
 
-	struct page *page;
+	netmem_ref netmem;
 	struct dentry *pp_dfs;
 	struct dentry *qr_dfs;
 
-- 
2.17.1