datapath/linux/compat/include/net/netlink.h

   1 #ifndef __NET_NETLINK_WRAPPER_H
   2 #define __NET_NETLINK_WRAPPER_H 1
   3
   4 #include <linux/version.h>
   5 #include_next <net/netlink.h>
   6
   7 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,29)
   8 /* Before v2.6.29, a NLA_NESTED attribute, if it was present, was not allowed
   9  * to be empty.  However, OVS depends on the ability to accept empty
  10  * attributes.  For example, a present but empty ODP_FLOW_ATTR_ACTIONS on
  11  * ODP_FLOW_CMD_SET replaces the existing set of actions by an empty "drop"
  12  * action, whereas a missing ODP_FLOW_ATTR_ACTIONS leaves the existing
  13  * actions, if any, unchanged.
  14  *
  15  * NLA_NESTED is different from NLA_UNSPEC in only two ways:
  16  *
  17  * - If the size of the nested attributes is zero, no further size checks
  18  *   are performed.
  19  *
  20  * - If the size of the nested attributes is not zero and no length
  21  *   parameter is specified the minimum size of nested attributes is
  22  *   NLA_HDRLEN.
  23  *
  24  * nla_parse_nested() validates that there is at least enough space for
  25  * NLA_HDRLEN, so neither of these conditions are important, and we might
  26  * as well use NLA_UNSPEC with old kernels.
  27  */
  28 #undef NLA_NESTED
  29 #define NLA_NESTED NLA_UNSPEC
  30 #endif
  31
  32 #ifndef NLA_PUT_BE16
  33 #define NLA_PUT_BE16(skb, attrtype, value) \
  34         NLA_PUT_TYPE(skb, __be16, attrtype, value)
  35 #endif  /* !NLA_PUT_BE16 */
  36
  37 #ifndef NLA_PUT_BE32
  38 #define NLA_PUT_BE32(skb, attrtype, value) \
  39         NLA_PUT_TYPE(skb, __be32, attrtype, value)
  40 #endif  /* !NLA_PUT_BE32 */
  41
  42 #ifndef NLA_PUT_BE64
  43 #define NLA_PUT_BE64(skb, attrtype, value) \
  44         NLA_PUT_TYPE(skb, __be64, attrtype, value)
  45 #endif  /* !NLA_PUT_BE64 */
  46
  47 #ifndef HAVE_NLA_GET_BE16
  48 /**
  49  * nla_get_be16 - return payload of __be16 attribute
  50  * @nla: __be16 netlink attribute
  51  */
  52 static inline __be16 nla_get_be16(const struct nlattr *nla)
  53 {
  54         return *(__be16 *) nla_data(nla);
  55 }
  56 #endif  /* !HAVE_NLA_GET_BE16 */
  57
  58 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,19)
  59 /**
  60  * nla_get_be32 - return payload of __be32 attribute
  61  * @nla: __be32 netlink attribute
  62  */
  63 static inline __be32 nla_get_be32(const struct nlattr *nla)
  64 {
  65         return *(__be32 *) nla_data(nla);
  66 }
  67 #endif
  68
  69 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,29)
  70 /* These functions' nlattr source arguments weren't "const" before 2.6.29, so
  71  * cast their arguments to the non-"const" versions.  Using macros for this
  72  * isn't exactly a brilliant idea, but it seems less error-prone than copying
  73  * the definitions of all umpteen functions. */
  74 #define nla_get_u64(nla)   (nla_get_u64)  ((struct nlattr *) (nla))
  75 #define nla_get_u32(nla)   (nla_get_u32)  ((struct nlattr *) (nla))
  76 #define nla_get_u16(nla)   (nla_get_u16)  ((struct nlattr *) (nla))
  77 #define nla_get_u8(nla)    (nla_get_u8)   ((struct nlattr *) (nla))
  78 /* nla_get_be64 is handled separately below. */
  79 #define nla_get_be32(nla)  (nla_get_be32) ((struct nlattr *) (nla))
  80 #define nla_get_be16(nla)  (nla_get_be16) ((struct nlattr *) (nla))
  81 #define nla_get_be8(nla)   (nla_get_be8)  ((struct nlattr *) (nla))
  82 #define nla_get_flag(nla)  (nla_get_flag) ((struct nlattr *) (nla))
  83 #define nla_get_msecs(nla) (nla_get_msecs)((struct nlattr *) (nla))
  84 #define nla_memcpy(dst, src, count) \
  85         (nla_memcpy)(dst, (struct nlattr *)(src), count)
  86 #endif
  87
  88 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,34)
  89 /* This function was introduced in 2.6.31, but initially it performed an
  90  * unaligned access, so we replace it up to 2.6.34 where it was fixed.  */
  91 #define nla_get_be64 rpl_nla_get_be64
  92 static inline __be64 nla_get_be64(const struct nlattr *nla)
  93 {
  94         __be64 tmp;
  95
  96         /* The additional cast is necessary because  */
  97         nla_memcpy(&tmp, (struct nlattr *) nla, sizeof(tmp));
  98
  99         return tmp;
 100 }
 101 #endif
 102
 103 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,24)
 104 /**
 105  * nla_type - attribute type
 106  * @nla: netlink attribute
 107  */
 108 static inline int nla_type(const struct nlattr *nla)
 109 {
 110         return nla->nla_type & NLA_TYPE_MASK;
 111 }
 112 #endif
 113
 114 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,22)
 115 #define nla_parse_nested(tb, maxtype, nla, policy) \
 116         nla_parse_nested(tb, maxtype, (struct nlattr *)(nla), (struct nla_policy *)(policy))
 117 #elif LINUX_VERSION_CODE < KERNEL_VERSION(2,6,29)
 118 #define nla_parse_nested(tb, maxtype, nla, policy) \
 119         nla_parse_nested(tb, maxtype, (struct nlattr *)(nla), policy)
 120 #endif
 121
 122 #ifndef nla_for_each_nested
 123 #define nla_for_each_nested(pos, nla, rem) \
 124         nla_for_each_attr(pos, nla_data(nla), nla_len(nla), rem)
 125 #endif
 126
 127 #ifndef HAVE_NLA_FIND_NESTED
 128 static inline struct nlattr *nla_find_nested(struct nlattr *nla, int attrtype)
 129 {
 130         return nla_find(nla_data(nla), nla_len(nla), attrtype);
 131 }
 132 #endif
 133
 134 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,19)
 135 /**
 136  * nlmsg_report - need to report back to application?
 137  * @nlh: netlink message header
 138  *
 139  * Returns 1 if a report back to the application is requested.
 140  */
 141 static inline int nlmsg_report(const struct nlmsghdr *nlh)
 142 {
 143         return !!(nlh->nlmsg_flags & NLM_F_ECHO);
 144 }
 145
 146 extern int              nlmsg_notify(struct sock *sk, struct sk_buff *skb,
 147                                      u32 pid, unsigned int group, int report,
 148                                      gfp_t flags);
 149 #endif  /* linux kernel < 2.6.19 */
 150
 151 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,19)
 152 /* Before 2.6.19 the 'flags' parameter was missing, so replace it.  We have to
 153  * #include <net/genetlink.h> first because the 2.6.18 version of that header
 154  * has an inline call to nlmsg_multicast() without, of course, any 'flags'
 155  * argument. */
 156 #define nlmsg_multicast rpl_nlmsg_multicast
 157 static inline int nlmsg_multicast(struct sock *sk, struct sk_buff *skb,
 158                                   u32 pid, unsigned int group, gfp_t flags)
 159 {
 160         int err;
 161
 162         NETLINK_CB(skb).dst_group = group;
 163
 164         err = netlink_broadcast(sk, skb, pid, group, flags);
 165         if (err > 0)
 166                 err = 0;
 167
 168         return err;
 169 }
 170 #endif  /* linux kernel < 2.6.19 */
 171
 172 #endif /* net/netlink.h */