[PATCH net-next 1/3] xen-netback: move netback_probe() and netback_remove() to the end...

From: Paul Durrant
Date: Tue Dec 17 2019 - 08:32:33 EST


...of xenbus.c

This is a cosmetic function re-ordering to reduce churn in a subsequent
patch. Some style fix-up was done to make checkpatch.pl happier.

No functional change.

Signed-off-by: Paul Durrant <pdurrant@xxxxxxxxxx>
---
Cc: Wei Liu <wei.liu@xxxxxxxxxx>
Cc: Paul Durrant <paul@xxxxxxx>
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
---
drivers/net/xen-netback/xenbus.c | 353 +++++++++++++++----------------
1 file changed, 174 insertions(+), 179 deletions(-)

diff --git a/drivers/net/xen-netback/xenbus.c b/drivers/net/xen-netback/xenbus.c
index f533b7372d59..bb61316d79de 100644
--- a/drivers/net/xen-netback/xenbus.c
+++ b/drivers/net/xen-netback/xenbus.c
@@ -195,185 +195,6 @@ static void xenvif_debugfs_delif(struct xenvif *vif)
}
#endif /* CONFIG_DEBUG_FS */

-static int netback_remove(struct xenbus_device *dev)
-{
- struct backend_info *be = dev_get_drvdata(&dev->dev);
-
- set_backend_state(be, XenbusStateClosed);
-
- unregister_hotplug_status_watch(be);
- if (be->vif) {
- kobject_uevent(&dev->dev.kobj, KOBJ_OFFLINE);
- xen_unregister_watchers(be->vif);
- xenbus_rm(XBT_NIL, dev->nodename, "hotplug-status");
- xenvif_free(be->vif);
- be->vif = NULL;
- }
- kfree(be->hotplug_script);
- kfree(be);
- dev_set_drvdata(&dev->dev, NULL);
- return 0;
-}
-
-
-/**
- * Entry point to this code when a new device is created. Allocate the basic
- * structures and switch to InitWait.
- */
-static int netback_probe(struct xenbus_device *dev,
- const struct xenbus_device_id *id)
-{
- const char *message;
- struct xenbus_transaction xbt;
- int err;
- int sg;
- const char *script;
- struct backend_info *be = kzalloc(sizeof(struct backend_info),
- GFP_KERNEL);
- if (!be) {
- xenbus_dev_fatal(dev, -ENOMEM,
- "allocating backend structure");
- return -ENOMEM;
- }
-
- be->dev = dev;
- dev_set_drvdata(&dev->dev, be);
-
- be->state = XenbusStateInitialising;
- err = xenbus_switch_state(dev, XenbusStateInitialising);
- if (err)
- goto fail;
-
- sg = 1;
-
- do {
- err = xenbus_transaction_start(&xbt);
- if (err) {
- xenbus_dev_fatal(dev, err, "starting transaction");
- goto fail;
- }
-
- err = xenbus_printf(xbt, dev->nodename, "feature-sg", "%d", sg);
- if (err) {
- message = "writing feature-sg";
- goto abort_transaction;
- }
-
- err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv4",
- "%d", sg);
- if (err) {
- message = "writing feature-gso-tcpv4";
- goto abort_transaction;
- }
-
- err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv6",
- "%d", sg);
- if (err) {
- message = "writing feature-gso-tcpv6";
- goto abort_transaction;
- }
-
- /* We support partial checksum setup for IPv6 packets */
- err = xenbus_printf(xbt, dev->nodename,
- "feature-ipv6-csum-offload",
- "%d", 1);
- if (err) {
- message = "writing feature-ipv6-csum-offload";
- goto abort_transaction;
- }
-
- /* We support rx-copy path. */
- err = xenbus_printf(xbt, dev->nodename,
- "feature-rx-copy", "%d", 1);
- if (err) {
- message = "writing feature-rx-copy";
- goto abort_transaction;
- }
-
- /*
- * We don't support rx-flip path (except old guests who don't
- * grok this feature flag).
- */
- err = xenbus_printf(xbt, dev->nodename,
- "feature-rx-flip", "%d", 0);
- if (err) {
- message = "writing feature-rx-flip";
- goto abort_transaction;
- }
-
- /* We support dynamic multicast-control. */
- err = xenbus_printf(xbt, dev->nodename,
- "feature-multicast-control", "%d", 1);
- if (err) {
- message = "writing feature-multicast-control";
- goto abort_transaction;
- }
-
- err = xenbus_printf(xbt, dev->nodename,
- "feature-dynamic-multicast-control",
- "%d", 1);
- if (err) {
- message = "writing feature-dynamic-multicast-control";
- goto abort_transaction;
- }
-
- err = xenbus_transaction_end(xbt, 0);
- } while (err == -EAGAIN);
-
- if (err) {
- xenbus_dev_fatal(dev, err, "completing transaction");
- goto fail;
- }
-
- /*
- * Split event channels support, this is optional so it is not
- * put inside the above loop.
- */
- err = xenbus_printf(XBT_NIL, dev->nodename,
- "feature-split-event-channels",
- "%u", separate_tx_rx_irq);
- if (err)
- pr_debug("Error writing feature-split-event-channels\n");
-
- /* Multi-queue support: This is an optional feature. */
- err = xenbus_printf(XBT_NIL, dev->nodename,
- "multi-queue-max-queues", "%u", xenvif_max_queues);
- if (err)
- pr_debug("Error writing multi-queue-max-queues\n");
-
- err = xenbus_printf(XBT_NIL, dev->nodename,
- "feature-ctrl-ring",
- "%u", true);
- if (err)
- pr_debug("Error writing feature-ctrl-ring\n");
-
- script = xenbus_read(XBT_NIL, dev->nodename, "script", NULL);
- if (IS_ERR(script)) {
- err = PTR_ERR(script);
- xenbus_dev_fatal(dev, err, "reading script");
- goto fail;
- }
-
- be->hotplug_script = script;
-
-
- /* This kicks hotplug scripts, so do it immediately. */
- err = backend_create_xenvif(be);
- if (err)
- goto fail;
-
- return 0;
-
-abort_transaction:
- xenbus_transaction_end(xbt, 1);
- xenbus_dev_fatal(dev, err, "%s", message);
-fail:
- pr_debug("failed\n");
- netback_remove(dev);
- return err;
-}
-
-
/*
* Handle the creation of the hotplug script environment. We add the script
* and vif variables to the environment, for the benefit of the vif-* hotplug
@@ -1128,6 +949,180 @@ static int read_xenbus_vif_flags(struct backend_info *be)
return 0;
}

+static int netback_remove(struct xenbus_device *dev)
+{
+ struct backend_info *be = dev_get_drvdata(&dev->dev);
+
+ set_backend_state(be, XenbusStateClosed);
+
+ unregister_hotplug_status_watch(be);
+ if (be->vif) {
+ kobject_uevent(&dev->dev.kobj, KOBJ_OFFLINE);
+ xen_unregister_watchers(be->vif);
+ xenbus_rm(XBT_NIL, dev->nodename, "hotplug-status");
+ xenvif_free(be->vif);
+ be->vif = NULL;
+ }
+ kfree(be->hotplug_script);
+ kfree(be);
+ dev_set_drvdata(&dev->dev, NULL);
+ return 0;
+}
+
+/**
+ * Entry point to this code when a new device is created. Allocate the basic
+ * structures and switch to InitWait.
+ */
+static int netback_probe(struct xenbus_device *dev,
+ const struct xenbus_device_id *id)
+{
+ const char *message;
+ struct xenbus_transaction xbt;
+ int err;
+ int sg;
+ const char *script;
+ struct backend_info *be = kzalloc(sizeof(*be), GFP_KERNEL);
+
+ if (!be) {
+ xenbus_dev_fatal(dev, -ENOMEM,
+ "allocating backend structure");
+ return -ENOMEM;
+ }
+
+ be->dev = dev;
+ dev_set_drvdata(&dev->dev, be);
+
+ be->state = XenbusStateInitialising;
+ err = xenbus_switch_state(dev, XenbusStateInitialising);
+ if (err)
+ goto fail;
+
+ sg = 1;
+
+ do {
+ err = xenbus_transaction_start(&xbt);
+ if (err) {
+ xenbus_dev_fatal(dev, err, "starting transaction");
+ goto fail;
+ }
+
+ err = xenbus_printf(xbt, dev->nodename, "feature-sg", "%d", sg);
+ if (err) {
+ message = "writing feature-sg";
+ goto abort_transaction;
+ }
+
+ err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv4",
+ "%d", sg);
+ if (err) {
+ message = "writing feature-gso-tcpv4";
+ goto abort_transaction;
+ }
+
+ err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv6",
+ "%d", sg);
+ if (err) {
+ message = "writing feature-gso-tcpv6";
+ goto abort_transaction;
+ }
+
+ /* We support partial checksum setup for IPv6 packets */
+ err = xenbus_printf(xbt, dev->nodename,
+ "feature-ipv6-csum-offload",
+ "%d", 1);
+ if (err) {
+ message = "writing feature-ipv6-csum-offload";
+ goto abort_transaction;
+ }
+
+ /* We support rx-copy path. */
+ err = xenbus_printf(xbt, dev->nodename,
+ "feature-rx-copy", "%d", 1);
+ if (err) {
+ message = "writing feature-rx-copy";
+ goto abort_transaction;
+ }
+
+ /* We don't support rx-flip path (except old guests who
+ * don't grok this feature flag).
+ */
+ err = xenbus_printf(xbt, dev->nodename,
+ "feature-rx-flip", "%d", 0);
+ if (err) {
+ message = "writing feature-rx-flip";
+ goto abort_transaction;
+ }
+
+ /* We support dynamic multicast-control. */
+ err = xenbus_printf(xbt, dev->nodename,
+ "feature-multicast-control", "%d", 1);
+ if (err) {
+ message = "writing feature-multicast-control";
+ goto abort_transaction;
+ }
+
+ err = xenbus_printf(xbt, dev->nodename,
+ "feature-dynamic-multicast-control",
+ "%d", 1);
+ if (err) {
+ message = "writing feature-dynamic-multicast-control";
+ goto abort_transaction;
+ }
+
+ err = xenbus_transaction_end(xbt, 0);
+ } while (err == -EAGAIN);
+
+ if (err) {
+ xenbus_dev_fatal(dev, err, "completing transaction");
+ goto fail;
+ }
+
+ /* Split event channels support, this is optional so it is not
+ * put inside the above loop.
+ */
+ err = xenbus_printf(XBT_NIL, dev->nodename,
+ "feature-split-event-channels",
+ "%u", separate_tx_rx_irq);
+ if (err)
+ pr_debug("Error writing feature-split-event-channels\n");
+
+ /* Multi-queue support: This is an optional feature. */
+ err = xenbus_printf(XBT_NIL, dev->nodename,
+ "multi-queue-max-queues", "%u", xenvif_max_queues);
+ if (err)
+ pr_debug("Error writing multi-queue-max-queues\n");
+
+ err = xenbus_printf(XBT_NIL, dev->nodename,
+ "feature-ctrl-ring",
+ "%u", true);
+ if (err)
+ pr_debug("Error writing feature-ctrl-ring\n");
+
+ script = xenbus_read(XBT_NIL, dev->nodename, "script", NULL);
+ if (IS_ERR(script)) {
+ err = PTR_ERR(script);
+ xenbus_dev_fatal(dev, err, "reading script");
+ goto fail;
+ }
+
+ be->hotplug_script = script;
+
+ /* This kicks hotplug scripts, so do it immediately. */
+ err = backend_create_xenvif(be);
+ if (err)
+ goto fail;
+
+ return 0;
+
+abort_transaction:
+ xenbus_transaction_end(xbt, 1);
+ xenbus_dev_fatal(dev, err, "%s", message);
+fail:
+ pr_debug("failed\n");
+ netback_remove(dev);
+ return err;
+}
+
static const struct xenbus_device_id netback_ids[] = {
{ "vif" },
{ "" }
--
2.20.1