From: Cong Wang <xiyou.wangcong@gmail.com>
Date: Thu, 25 Jan 2018 18:26:22 -0800
Subject: net: introduce helper dev_change_tx_queue_len()
Patch-mainline: v4.16-rc1
Git-commit: 6a643ddb5624be7e0694d49f5765a8d41c1ab6d0
References: bsc#1109837
This patch promotes the local change_tx_queue_len() to a core
helper function, dev_change_tx_queue_len(), so that rtnetlink
and net-sysfs could share the code. This also prepares for the
following patch.
Note, the -EFAULT in the original code doesn't make sense,
we should propagate the errno from notifiers.
Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
include/linux/netdevice.h | 1 +
net/core/dev.c | 28 ++++++++++++++++++++++++++++
net/core/net-sysfs.c | 25 +------------------------
net/core/rtnetlink.c | 16 ++++------------
4 files changed, 34 insertions(+), 36 deletions(-)
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -3320,6 +3320,7 @@ int dev_set_alias(struct net_device *, c
int dev_change_net_namespace(struct net_device *, struct net *, const char *);
int __dev_set_mtu(struct net_device *, int);
int dev_set_mtu(struct net_device *, int);
+int dev_change_tx_queue_len(struct net_device *, unsigned long);
void dev_set_group(struct net_device *, int);
int dev_set_mac_address(struct net_device *, struct sockaddr *);
int dev_change_carrier(struct net_device *, bool new_carrier);
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -7027,6 +7027,34 @@ int dev_set_mtu(struct net_device *dev,
EXPORT_SYMBOL(dev_set_mtu);
/**
+ * dev_change_tx_queue_len - Change TX queue length of a netdevice
+ * @dev: device
+ * @new_len: new tx queue length
+ */
+int dev_change_tx_queue_len(struct net_device *dev, unsigned long new_len)
+{
+ unsigned int orig_len = dev->tx_queue_len;
+ int res;
+
+ if (new_len != (unsigned int)new_len)
+ return -ERANGE;
+
+ if (new_len != orig_len) {
+ dev->tx_queue_len = new_len;
+ res = call_netdevice_notifiers(NETDEV_CHANGE_TX_QUEUE_LEN, dev);
+ res = notifier_to_errno(res);
+ if (res) {
+ netdev_err(dev,
+ "refused to change device tx_queue_len\n");
+ dev->tx_queue_len = orig_len;
+ return res;
+ }
+ }
+
+ return 0;
+}
+
+/**
* dev_set_group - Change group this device belongs to
* @dev: device
* @new_group: group this device should belong to
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -321,29 +321,6 @@ static ssize_t flags_store(struct device
}
NETDEVICE_SHOW_RW(flags, fmt_hex);
-static int change_tx_queue_len(struct net_device *dev, unsigned long new_len)
-{
- unsigned int orig_len = dev->tx_queue_len;
- int res;
-
- if (new_len != (unsigned int)new_len)
- return -ERANGE;
-
- if (new_len != orig_len) {
- dev->tx_queue_len = new_len;
- res = call_netdevice_notifiers(NETDEV_CHANGE_TX_QUEUE_LEN, dev);
- res = notifier_to_errno(res);
- if (res) {
- netdev_err(dev,
- "refused to change device tx_queue_len\n");
- dev->tx_queue_len = orig_len;
- return -EFAULT;
- }
- }
-
- return 0;
-}
-
static ssize_t tx_queue_len_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t len)
@@ -351,7 +328,7 @@ static ssize_t tx_queue_len_store(struct
if (!capable(CAP_NET_ADMIN))
return -EPERM;
- return netdev_store(dev, attr, buf, len, change_tx_queue_len);
+ return netdev_store(dev, attr, buf, len, dev_change_tx_queue_len);
}
NETDEVICE_SHOW_RW(tx_queue_len, fmt_dec);
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -2123,19 +2123,11 @@ static int do_setlink(const struct sk_bu
if (tb[IFLA_TXQLEN]) {
unsigned int value = nla_get_u32(tb[IFLA_TXQLEN]);
- unsigned int orig_len = dev->tx_queue_len;
- if (dev->tx_queue_len ^ value) {
- dev->tx_queue_len = value;
- err = call_netdevice_notifiers(
- NETDEV_CHANGE_TX_QUEUE_LEN, dev);
- err = notifier_to_errno(err);
- if (err) {
- dev->tx_queue_len = orig_len;
- goto errout;
- }
- status |= DO_SETLINK_MODIFIED;
- }
+ err = dev_change_tx_queue_len(dev, value);
+ if (err)
+ goto errout;
+ status |= DO_SETLINK_MODIFIED;
}
if (tb[IFLA_OPERSTATE])