From: Hans Westgaard Ry <hans.westgaard.ry@oracle.com>
Date: Wed, 15 Jan 2020 12:43:38 +0000 (+0200)
Subject: net/rds: Detect need of On-Demand-Paging memory registration
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=c4c86abb3f9fb3d5bc113fb996298a30ec63e07b;p=linux.git

net/rds: Detect need of On-Demand-Paging memory registration

Add code to check if memory intended for RDMA is FS-DAX-memory. RDS
will fail with error code EOPNOTSUPP if FS-DAX-memory is detected.

Signed-off-by: Hans Westgaard Ry <hans.westgaard.ry@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
---

diff --git a/net/rds/rdma.c b/net/rds/rdma.c
index 916f5ec373d8e..eb23c38ce2b34 100644
--- a/net/rds/rdma.c
+++ b/net/rds/rdma.c
@@ -156,11 +156,13 @@ void rds_rdma_drop_keys(struct rds_sock *rs)
 static int rds_pin_pages(unsigned long user_addr, unsigned int nr_pages,
 			struct page **pages, int write)
 {
+	unsigned int gup_flags = FOLL_LONGTERM;
 	int ret;
 
-	ret = get_user_pages_fast(user_addr, nr_pages, write ? FOLL_WRITE : 0,
-				  pages);
+	if (write)
+		gup_flags |= FOLL_WRITE;
 
+	ret = get_user_pages_fast(user_addr, nr_pages, gup_flags, pages);
 	if (ret >= 0 && ret < nr_pages) {
 		while (ret--)
 			put_page(pages[ret]);