platform: allow setting drivers-autoprobe on SR-IOV PFs

It is possible to tell kernel not to automatically autoprobe drivers
for VFs. This is useful, for example, if the VF must be used by a VM.

5 files changed, 69 insertions, 38 deletions

diff --git a/src/devices/nm-device.c b/src/devices/nm-device.c
index aa2a389a5d..8844672ab5 100644
--- a/src/devices/nm-device.c
+++ b/src/devices/nm-device.c
@@ -3951,8 +3951,8 @@ device_init_sriov_num_vfs (NMDevice *self)
 		                                          NULL);
 		num_vfs = _nm_utils_ascii_str_to_int64 (value, 10, 0, G_MAXINT32, -1);
 		if (num_vfs >= 0) {
-			nm_platform_link_set_sriov_num_vfs (nm_device_get_platform (self),
-			                                    priv->ifindex, num_vfs);
+			nm_platform_link_set_sriov_params (nm_device_get_platform (self),
+			                                   priv->ifindex, num_vfs, -1);
 		}
 	}
 }
diff --git a/src/platform/nm-fake-platform.c b/src/platform/nm-fake-platform.c
index f8f4627ed0..d8d192c712 100644
--- a/src/platform/nm-fake-platform.c
+++ b/src/platform/nm-fake-platform.c
@@ -602,12 +602,6 @@ link_set_mtu (NMPlatform *platform, int ifindex, guint32 mtu)
 	return NM_PLATFORM_ERROR_SUCCESS;
 }
 
-static gboolean
-link_set_sriov_num_vfs (NMPlatform *platform, int ifindex, guint num_vfs)
-{
-	return TRUE;
-}
-
 static const char *
 link_get_udi (NMPlatform *platform, int ifindex)
 {
@@ -1422,7 +1416,6 @@ nm_fake_platform_class_init (NMFakePlatformClass *klass)
 
 	platform_class->link_set_address = link_set_address;
 	platform_class->link_set_mtu = link_set_mtu;
-	platform_class->link_set_sriov_num_vfs = link_set_sriov_num_vfs;
 
 	platform_class->link_get_driver_info = link_get_driver_info;
 
diff --git a/src/platform/nm-linux-platform.c b/src/platform/nm-linux-platform.c
index e02269f6eb..19821a87c3 100644
--- a/src/platform/nm-linux-platform.c
+++ b/src/platform/nm-linux-platform.c
@@ -5528,16 +5528,18 @@ nla_put_failure:
 }
 
 static gboolean
-link_set_sriov_num_vfs (NMPlatform *platform, int ifindex, guint num_vfs)
+link_set_sriov_params (NMPlatform *platform,
+                       int ifindex,
+                       guint num_vfs,
+                       int autoprobe)
 {
 	nm_auto_pop_netns NMPNetns *netns = NULL;
 	nm_auto_close int dirfd = -1;
-	int total, current;
+	gboolean current_autoprobe;
+	guint total, current_num;
 	char ifname[IFNAMSIZ];
 	char buf[64];
 
-	_LOGD ("link: change %d: num VFs: %u", ifindex, num_vfs);
-
 	if (!nm_platform_netns_push (platform, &netns))
 		return FALSE;
 
@@ -5545,46 +5547,69 @@ link_set_sriov_num_vfs (NMPlatform *platform, int ifindex, guint num_vfs)
 	if (!dirfd)
 		return FALSE;
 
-	total = nm_platform_sysctl_get_int32 (platform,
-	                                      NMP_SYSCTL_PATHID_NETDIR (dirfd,
-	                                                                ifname,
-	                                                                "device/sriov_totalvfs"),
-	                                      -1);
-	if (total < 1)
+	total = nm_platform_sysctl_get_int_checked (platform,
+	                                            NMP_SYSCTL_PATHID_NETDIR (dirfd,
+	                                                                      ifname,
+	                                                                      "device/sriov_totalvfs"),
+	                                            10, 0, G_MAXUINT, 0);
+	if (errno)
 		return FALSE;
 	if (num_vfs > total) {
 		_LOGW ("link: %d only supports %u VFs (requested %u)", ifindex, total, num_vfs);
 		num_vfs = total;
 	}
 
-	current = nm_platform_sysctl_get_int32 (platform,
-	                                        NMP_SYSCTL_PATHID_NETDIR (dirfd,
-	                                                                  ifname,
-	                                                                  "device/sriov_numvfs"),
-	                                        -1);
-	if (current == num_vfs)
+	/*
+	 * Take special care when setting new values:
+	 *  - don't touch anything if the right values are already set
+	 *  - to change the number of VFs or autoprobe we need to destroy existing VFs
+	 *  - the autoprobe setting is irrelevant when numvfs is zero
+	 */
+	current_num = nm_platform_sysctl_get_int_checked (platform,
+	                                                  NMP_SYSCTL_PATHID_NETDIR (dirfd,
+	                                                                            ifname,
+	                                                                            "device/sriov_numvfs"),
+	                                                  10, 0, G_MAXUINT, 0);
+	current_autoprobe = nm_platform_sysctl_get_int_checked (platform,
+	                                                        NMP_SYSCTL_PATHID_NETDIR (dirfd,
+	                                                                                  ifname,
+	                                                                                  "device/sriov_drivers_autoprobe"),
+	                                                        10, 0, G_MAXUINT, 0);
+	if (   current_num == num_vfs
+	    && (autoprobe == -1 || current_autoprobe == autoprobe))
 		return TRUE;
 
-	if (current != 0) {
-		/* We need to destroy all other VFs before changing the value */
+	if (current_num != 0) {
+		/* We need to destroy all other VFs before changing any value */
 		if (!nm_platform_sysctl_set (NM_PLATFORM_GET,
 		                             NMP_SYSCTL_PATHID_NETDIR (dirfd,
 		                                                       ifname,
 		                                                      "device/sriov_numvfs"),
 		                             "0")) {
-			_LOGW ("link: couldn't set SR-IOV num_vfs to %d: %s", 0, strerror (errno));
+			_LOGW ("link: couldn't reset SR-IOV num_vfs: %s", strerror (errno));
 			return FALSE;
 		}
-		if (num_vfs == 0)
-			return TRUE;
 	}
 
-	/* Finally, set the desired value */
+	if (num_vfs == 0)
+		return TRUE;
+
+	if (   autoprobe >= 0
+	    && current_autoprobe != autoprobe
+	    && !nm_platform_sysctl_set (NM_PLATFORM_GET,
+	                                NMP_SYSCTL_PATHID_NETDIR (dirfd,
+	                                                          ifname,
+	                                                          "device/sriov_drivers_autoprobe"),
+	                                nm_sprintf_buf (buf, "%d", autoprobe))) {
+		_LOGW ("link: couldn't set SR-IOV drivers-autoprobe to %d: %s", autoprobe, strerror (errno));
+		return FALSE;
+	}
+
 	if (!nm_platform_sysctl_set (NM_PLATFORM_GET,
 	                             NMP_SYSCTL_PATHID_NETDIR (dirfd,
 	                                                       ifname,
 	                                                       "device/sriov_numvfs"),
-	                             nm_sprintf_buf (buf, "%d", num_vfs))) {
+	                             nm_sprintf_buf (buf, "%u", num_vfs))) {
 		_LOGW ("link: couldn't set SR-IOV num_vfs to %d: %s", num_vfs, strerror (errno));
 		return FALSE;
 	}
@@ -7735,7 +7760,7 @@ nm_linux_platform_class_init (NMLinuxPlatformClass *klass)
 	platform_class->link_get_permanent_address = link_get_permanent_address;
 	platform_class->link_set_mtu = link_set_mtu;
 	platform_class->link_set_name = link_set_name;
-	platform_class->link_set_sriov_num_vfs = link_set_sriov_num_vfs;
+	platform_class->link_set_sriov_params = link_set_sriov_params;
 
 	platform_class->link_get_physical_port_id = link_get_physical_port_id;
 	platform_class->link_get_dev_id = link_get_dev_id;
diff --git a/src/platform/nm-platform.c b/src/platform/nm-platform.c
index 96465e3dd5..1146a07309 100644
--- a/src/platform/nm-platform.c
+++ b/src/platform/nm-platform.c
@@ -1463,18 +1463,31 @@ nm_platform_link_supports_sriov (NMPlatform *self, int ifindex)
 	return klass->link_supports_sriov (self, ifindex);
 }
 
+/**
+ * nm_platform_link_set_sriov_params:
+ * @self: platform instance
+ * @ifindex: the index of the interface to change
+ * @num_vfs: the number of VFs to create
+ * @autoprobe: -1 to keep the current autoprobe-drivers value,
+ *   or {0,1} to set a new value
+ */
 gboolean
-nm_platform_link_set_sriov_num_vfs (NMPlatform *self, int ifindex, guint num_vfs)
+nm_platform_link_set_sriov_params (NMPlatform *self,
+                                   int ifindex,
+                                   guint num_vfs,
+                                   int autoprobe)
 {
 	_CHECK_SELF (self, klass, FALSE);
 
 	g_return_val_if_fail (ifindex > 0, FALSE);
+	g_return_val_if_fail (NM_IN_SET (autoprobe, -1, 0, 1), FALSE);
 
-	_LOGD ("link: setting %u VFs for %s (%d)",
+	_LOGD ("link: setting %u total VFs and autoprobe %d for %s (%d)",
 	       num_vfs,
+	       autoprobe,
 	       nm_strquote_a (25, nm_platform_link_get_name (self, ifindex)),
 	       ifindex);
-	return klass->link_set_sriov_num_vfs (self, ifindex, num_vfs);
+	return klass->link_set_sriov_params (self, ifindex, num_vfs, autoprobe);
 }
 
 /**
diff --git a/src/platform/nm-platform.h b/src/platform/nm-platform.h
index 00df7fa31d..01e13f2178 100644
--- a/src/platform/nm-platform.h
+++ b/src/platform/nm-platform.h
@@ -802,7 +802,7 @@ typedef struct {
 	NMPlatformError (*link_set_address) (NMPlatform *, int ifindex, gconstpointer address, size_t length);
 	NMPlatformError (*link_set_mtu) (NMPlatform *, int ifindex, guint32 mtu);
 	gboolean (*link_set_name) (NMPlatform *, int ifindex, const char *name);
-	gboolean (*link_set_sriov_num_vfs) (NMPlatform *, int ifindex, guint num_vfs);
+	gboolean (*link_set_sriov_params) (NMPlatform *, int ifindex, guint num_vfs, int autoprobe);
 
 	char *   (*link_get_physical_port_id) (NMPlatform *, int ifindex);
 	guint    (*link_get_dev_id) (NMPlatform *, int ifindex);
@@ -1193,7 +1193,7 @@ gboolean nm_platform_link_get_permanent_address (NMPlatform *self, int ifindex,
 NMPlatformError nm_platform_link_set_address (NMPlatform *self, int ifindex, const void *address, size_t length);
 NMPlatformError nm_platform_link_set_mtu (NMPlatform *self, int ifindex, guint32 mtu);
 gboolean nm_platform_link_set_name (NMPlatform *self, int ifindex, const char *name);
-gboolean nm_platform_link_set_sriov_num_vfs (NMPlatform *self, int ifindex, guint num_vfs);
+gboolean nm_platform_link_set_sriov_params (NMPlatform *self, int ifindex, guint num_vfs, int autoprobe);
 
 char    *nm_platform_link_get_physical_port_id (NMPlatform *self, int ifindex);
 guint    nm_platform_link_get_dev_id (NMPlatform *self, int ifindex);