[dpdk-stable] patch 'vfio: use contiguous mapping for IOVA as VA mode' has been queued to LTS release 18.11.3

[Kevin Traynor]

Hi,

FYI, your patch has been queued to LTS release 18.11.3

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 09/12/19. So please
shout if anyone has objections.

Also note that after the patch there's a diff of the upstream commit vs the
patch applied to the branch. This will indicate if there was any rebasing
needed to apply to the stable branch. If there were code changes for rebasing
(ie: not only metadata diffs), please double check that the rebase was
correctly done.

Queued patches are on a temporary branch at:
https://github.com/kevintraynor/dpdk-stable-queue

This queued commit can be viewed at:
https://github.com/kevintraynor/dpdk-stable-queue/commit/f61b77c388c4f0cdbc7447b6260278344f61a39c

Thanks.

Kevin Traynor

---
>From f61b77c388c4f0cdbc7447b6260278344f61a39c Mon Sep 17 00:00:00 2001
From: Anatoly Burakov <anatoly.burakov at intel.com>
Date: Tue, 23 Jul 2019 11:01:20 +0100
Subject: [PATCH] vfio: use contiguous mapping for IOVA as VA mode

[ upstream commit 78a6d7ed19353310fc83e75742e9e73ae17c1719 ]

When using IOVA as VA mode, there is no need to map segments
page by page. This normally isn't a problem, but it becomes one
when attempting to use DPDK in no-huge mode, where VFIO subsystem
simply runs out of space to store mappings.

Fix this for x86 by triggering different callbacks based on whether
IOVA as VA mode is enabled.

Fixes: 73a639085938 ("vfio: allow to map other memory regions")

Signed-off-by: Anatoly Burakov <anatoly.burakov at intel.com>
Tested-by: Andrius Sirvys <andrius.sirvys at intel.com>
---
 lib/librte_eal/linuxapp/eal/eal_vfio.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/lib/librte_eal/linuxapp/eal/eal_vfio.c b/lib/librte_eal/linuxapp/eal/eal_vfio.c
index 28b4ea66f..830b320d7 100644
--- a/lib/librte_eal/linuxapp/eal/eal_vfio.c
+++ b/lib/librte_eal/linuxapp/eal/eal_vfio.c
@@ -1233,4 +1233,17 @@ rte_vfio_get_group_num(const char *sysfs_base,
 }
 
+static int
+type1_map_contig(const struct rte_memseg_list *msl, const struct rte_memseg *ms,
+		size_t len, void *arg)
+{
+	int *vfio_container_fd = arg;
+
+	if (msl->external)
+		return 0;
+
+	return vfio_type1_dma_mem_map(*vfio_container_fd, ms->addr_64, ms->iova,
+			len, 1);
+}
+
 static int
 type1_map(const struct rte_memseg_list *msl, const struct rte_memseg *ms,
@@ -1290,4 +1303,11 @@ static int
 vfio_type1_dma_map(int vfio_container_fd)
 {
+	if (rte_eal_iova_mode() == RTE_IOVA_VA) {
+		/* with IOVA as VA mode, we can get away with mapping contiguous
+		 * chunks rather than going page-by-page.
+		 */
+		return rte_memseg_contig_walk(type1_map_contig,
+				&vfio_container_fd);
+	}
 	return rte_memseg_walk(type1_map, &vfio_container_fd);
 }
-- 
2.20.1

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2019-09-05 10:36:47.663097948 +0100
+++ 0002-vfio-use-contiguous-mapping-for-IOVA-as-VA-mode.patch	2019-09-05 10:36:47.438702246 +0100
@@ -1 +1 @@
-From 78a6d7ed19353310fc83e75742e9e73ae17c1719 Mon Sep 17 00:00:00 2001
+From f61b77c388c4f0cdbc7447b6260278344f61a39c Mon Sep 17 00:00:00 2001
@@ -5,0 +6,2 @@
+[ upstream commit 78a6d7ed19353310fc83e75742e9e73ae17c1719 ]
+
@@ -15 +16,0 @@
-Cc: stable at dpdk.org
@@ -20 +21 @@
- lib/librte_eal/linux/eal/eal_vfio.c | 20 ++++++++++++++++++++
+ lib/librte_eal/linuxapp/eal/eal_vfio.c | 20 ++++++++++++++++++++
@@ -23,5 +24,5 @@
-diff --git a/lib/librte_eal/linux/eal/eal_vfio.c b/lib/librte_eal/linux/eal/eal_vfio.c
-index ed04231b1..501c74f23 100644
---- a/lib/librte_eal/linux/eal/eal_vfio.c
-+++ b/lib/librte_eal/linux/eal/eal_vfio.c
-@@ -1232,4 +1232,17 @@ rte_vfio_get_group_num(const char *sysfs_base,
+diff --git a/lib/librte_eal/linuxapp/eal/eal_vfio.c b/lib/librte_eal/linuxapp/eal/eal_vfio.c
+index 28b4ea66f..830b320d7 100644
+--- a/lib/librte_eal/linuxapp/eal/eal_vfio.c
++++ b/lib/librte_eal/linuxapp/eal/eal_vfio.c
+@@ -1233,4 +1233,17 @@ rte_vfio_get_group_num(const char *sysfs_base,
@@ -45 +46 @@
-@@ -1301,4 +1314,11 @@ static int
+@@ -1290,4 +1303,11 @@ static int