Files
android_kernel_xiaomi_sm8450/net/ethtool/netlink.h
Michal Kubecek 041b1c5d4a ethtool: helper functions for netlink interface
Add common request/reply header definition and helpers to parse request
header and fill reply header. Provide ethnl_update_* helpers to update
structure members from request attributes (to be used for *_SET requests).

Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-12-27 16:40:01 -08:00

216 lines
6.0 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
#ifndef _NET_ETHTOOL_NETLINK_H
#define _NET_ETHTOOL_NETLINK_H
#include <linux/ethtool_netlink.h>
#include <linux/netdevice.h>
#include <net/genetlink.h>
#include <net/sock.h>
struct ethnl_req_info;
int ethnl_parse_header(struct ethnl_req_info *req_info,
const struct nlattr *nest, struct net *net,
struct netlink_ext_ack *extack, bool require_dev);
int ethnl_fill_reply_header(struct sk_buff *skb, struct net_device *dev,
u16 attrtype);
struct sk_buff *ethnl_reply_init(size_t payload, struct net_device *dev, u8 cmd,
u16 hdr_attrtype, struct genl_info *info,
void **ehdrp);
/**
* ethnl_strz_size() - calculate attribute length for fixed size string
* @s: ETH_GSTRING_LEN sized string (may not be null terminated)
*
* Return: total length of an attribute with null terminated string from @s
*/
static inline int ethnl_strz_size(const char *s)
{
return nla_total_size(strnlen(s, ETH_GSTRING_LEN) + 1);
}
/**
* ethnl_put_strz() - put string attribute with fixed size string
* @skb: skb with the message
* @attrype: attribute type
* @s: ETH_GSTRING_LEN sized string (may not be null terminated)
*
* Puts an attribute with null terminated string from @s into the message.
*
* Return: 0 on success, negative error code on failure
*/
static inline int ethnl_put_strz(struct sk_buff *skb, u16 attrtype,
const char *s)
{
unsigned int len = strnlen(s, ETH_GSTRING_LEN);
struct nlattr *attr;
attr = nla_reserve(skb, attrtype, len + 1);
if (!attr)
return -EMSGSIZE;
memcpy(nla_data(attr), s, len);
((char *)nla_data(attr))[len] = '\0';
return 0;
}
/**
* ethnl_update_u32() - update u32 value from NLA_U32 attribute
* @dst: value to update
* @attr: netlink attribute with new value or null
* @mod: pointer to bool for modification tracking
*
* Copy the u32 value from NLA_U32 netlink attribute @attr into variable
* pointed to by @dst; do nothing if @attr is null. Bool pointed to by @mod
* is set to true if this function changed the value of *dst, otherwise it
* is left as is.
*/
static inline void ethnl_update_u32(u32 *dst, const struct nlattr *attr,
bool *mod)
{
u32 val;
if (!attr)
return;
val = nla_get_u32(attr);
if (*dst == val)
return;
*dst = val;
*mod = true;
}
/**
* ethnl_update_u8() - update u8 value from NLA_U8 attribute
* @dst: value to update
* @attr: netlink attribute with new value or null
* @mod: pointer to bool for modification tracking
*
* Copy the u8 value from NLA_U8 netlink attribute @attr into variable
* pointed to by @dst; do nothing if @attr is null. Bool pointed to by @mod
* is set to true if this function changed the value of *dst, otherwise it
* is left as is.
*/
static inline void ethnl_update_u8(u8 *dst, const struct nlattr *attr,
bool *mod)
{
u8 val;
if (!attr)
return;
val = nla_get_u8(attr);
if (*dst == val)
return;
*dst = val;
*mod = true;
}
/**
* ethnl_update_bool32() - update u32 used as bool from NLA_U8 attribute
* @dst: value to update
* @attr: netlink attribute with new value or null
* @mod: pointer to bool for modification tracking
*
* Use the u8 value from NLA_U8 netlink attribute @attr to set u32 variable
* pointed to by @dst to 0 (if zero) or 1 (if not); do nothing if @attr is
* null. Bool pointed to by @mod is set to true if this function changed the
* logical value of *dst, otherwise it is left as is.
*/
static inline void ethnl_update_bool32(u32 *dst, const struct nlattr *attr,
bool *mod)
{
u8 val;
if (!attr)
return;
val = !!nla_get_u8(attr);
if (!!*dst == val)
return;
*dst = val;
*mod = true;
}
/**
* ethnl_update_binary() - update binary data from NLA_BINARY atribute
* @dst: value to update
* @len: destination buffer length
* @attr: netlink attribute with new value or null
* @mod: pointer to bool for modification tracking
*
* Use the u8 value from NLA_U8 netlink attribute @attr to rewrite data block
* of length @len at @dst by attribute payload; do nothing if @attr is null.
* Bool pointed to by @mod is set to true if this function changed the logical
* value of *dst, otherwise it is left as is.
*/
static inline void ethnl_update_binary(void *dst, unsigned int len,
const struct nlattr *attr, bool *mod)
{
if (!attr)
return;
if (nla_len(attr) < len)
len = nla_len(attr);
if (!memcmp(dst, nla_data(attr), len))
return;
memcpy(dst, nla_data(attr), len);
*mod = true;
}
/**
* ethnl_update_bitfield32() - update u32 value from NLA_BITFIELD32 attribute
* @dst: value to update
* @attr: netlink attribute with new value or null
* @mod: pointer to bool for modification tracking
*
* Update bits in u32 value which are set in attribute's mask to values from
* attribute's value. Do nothing if @attr is null or the value wouldn't change;
* otherwise, set bool pointed to by @mod to true.
*/
static inline void ethnl_update_bitfield32(u32 *dst, const struct nlattr *attr,
bool *mod)
{
struct nla_bitfield32 change;
u32 newval;
if (!attr)
return;
change = nla_get_bitfield32(attr);
newval = (*dst & ~change.selector) | (change.value & change.selector);
if (*dst == newval)
return;
*dst = newval;
*mod = true;
}
/**
* ethnl_reply_header_size() - total size of reply header
*
* This is an upper estimate so that we do not need to hold RTNL lock longer
* than necessary (to prevent rename between size estimate and composing the
* message). Accounts only for device ifindex and name as those are the only
* attributes ethnl_fill_reply_header() puts into the reply header.
*/
static inline unsigned int ethnl_reply_header_size(void)
{
return nla_total_size(nla_total_size(sizeof(u32)) +
nla_total_size(IFNAMSIZ));
}
/**
* struct ethnl_req_info - base type of request information for GET requests
* @dev: network device the request is for (may be null)
* @flags: request flags common for all request types
*
* This is a common base, additional members may follow after this structure.
*/
struct ethnl_req_info {
struct net_device *dev;
u32 flags;
};
#endif /* _NET_ETHTOOL_NETLINK_H */