diff options
| author | Jamal Hadi Salim | 2017-07-30 13:24:49 -0400 |
|---|---|---|
| committer | David S. Miller | 2017-07-30 19:28:08 -0700 |
| commit | 64c83d837329531252a1a0f0dfdd4fd607e1d8e9 (patch) | |
| tree | a764214643c24db912ab942efd1aa47365d179c9 /include/uapi | |
| parent | fbbeefdd21049fcf9437c809da3828b210577f36 (diff) | |
net netlink: Add new type NLA_BITFIELD32
Generic bitflags attribute content sent to the kernel by user.
With this netlink attr type the user can either set or unset a
flag in the kernel.
The value is a bitmap that defines the bit values being set
The selector is a bitmask that defines which value bit is to be
considered.
A check is made to ensure the rules that a kernel subsystem always
conforms to bitflags the kernel already knows about. i.e
if the user tries to set a bit flag that is not understood then
the _it will be rejected_.
In the most basic form, the user specifies the attribute policy as:
[ATTR_GOO] = { .type = NLA_BITFIELD32, .validation_data = &myvalidflags },
where myvalidflags is the bit mask of the flags the kernel understands.
If the user _does not_ provide myvalidflags then the attribute will
also be rejected.
Examples:
value = 0x0, and selector = 0x1
implies we are selecting bit 1 and we want to set its value to 0.
value = 0x2, and selector = 0x2
implies we are selecting bit 2 and we want to set its value to 1.
Suggested-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/uapi')
| -rw-r--r-- | include/uapi/linux/netlink.h | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/include/uapi/linux/netlink.h b/include/uapi/linux/netlink.h index f86127a46cfc..f4fc9c9e123d 100644 --- a/include/uapi/linux/netlink.h +++ b/include/uapi/linux/netlink.h @@ -226,5 +226,22 @@ struct nlattr { #define NLA_ALIGN(len) (((len) + NLA_ALIGNTO - 1) & ~(NLA_ALIGNTO - 1)) #define NLA_HDRLEN ((int) NLA_ALIGN(sizeof(struct nlattr))) +/* Generic 32 bitflags attribute content sent to the kernel. + * + * The value is a bitmap that defines the values being set + * The selector is a bitmask that defines which value is legit + * + * Examples: + * value = 0x0, and selector = 0x1 + * implies we are selecting bit 1 and we want to set its value to 0. + * + * value = 0x2, and selector = 0x2 + * implies we are selecting bit 2 and we want to set its value to 1. + * + */ +struct nla_bitfield32 { + __u32 value; + __u32 selector; +}; #endif /* _UAPI__LINUX_NETLINK_H */ |