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/* SPDX-License-Identifier: GPL-2.0-or-later */
#ifndef _NET_IPV6_GRO_H
#define _NET_IPV6_GRO_H
#include <linux/indirect_call_wrapper.h>
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/skbuff.h>
#include <net/udp.h>
struct napi_gro_cb {
/* Virtual address of skb_shinfo(skb)->frags[0].page + offset. */
void *frag0;
/* Length of frag0. */
unsigned int frag0_len;
/* This indicates where we are processing relative to skb->data. */
int data_offset;
/* This is non-zero if the packet cannot be merged with the new skb. */
u16 flush;
/* Save the IP ID here and check when we get to the transport layer */
u16 flush_id;
/* Number of segments aggregated. */
u16 count;
/* Start offset for remote checksum offload */
u16 gro_remcsum_start;
/* jiffies when first packet was created/queued */
unsigned long age;
/* Used in ipv6_gro_receive() and foo-over-udp */
u16 proto;
/* This is non-zero if the packet may be of the same flow. */
u8 same_flow:1;
/* Used in tunnel GRO receive */
u8 encap_mark:1;
/* GRO checksum is valid */
u8 csum_valid:1;
/* Number of checksums via CHECKSUM_UNNECESSARY */
u8 csum_cnt:3;
/* Free the skb? */
u8 free:2;
#define NAPI_GRO_FREE 1
#define NAPI_GRO_FREE_STOLEN_HEAD 2
/* Used in foo-over-udp, set in udp[46]_gro_receive */
u8 is_ipv6:1;
/* Used in GRE, set in fou/gue_gro_receive */
u8 is_fou:1;
/* Used to determine if flush_id can be ignored */
u8 is_atomic:1;
/* Number of gro_receive callbacks this packet already went through */
u8 recursion_counter:4;
/* GRO is done by frag_list pointer chaining. */
u8 is_flist:1;
/* used to support CHECKSUM_COMPLETE for tunneling protocols */
__wsum csum;
/* used in skb_gro_receive() slow path */
struct sk_buff *last;
};
#define NAPI_GRO_CB(skb) ((struct napi_gro_cb *)(skb)->cb)
#define GRO_RECURSION_LIMIT 15
static inline int gro_recursion_inc_test(struct sk_buff *skb)
{
return ++NAPI_GRO_CB(skb)->recursion_counter == GRO_RECURSION_LIMIT;
}
typedef struct sk_buff *(*gro_receive_t)(struct list_head *, struct sk_buff *);
static inline struct sk_buff *call_gro_receive(gro_receive_t cb,
struct list_head *head,
struct sk_buff *skb)
{
if (unlikely(gro_recursion_inc_test(skb))) {
NAPI_GRO_CB(skb)->flush |= 1;
return NULL;
}
return cb(head, skb);
}
typedef struct sk_buff *(*gro_receive_sk_t)(struct sock *, struct list_head *,
struct sk_buff *);
static inline struct sk_buff *call_gro_receive_sk(gro_receive_sk_t cb,
struct sock *sk,
struct list_head *head,
struct sk_buff *skb)
{
if (unlikely(gro_recursion_inc_test(skb))) {
NAPI_GRO_CB(skb)->flush |= 1;
return NULL;
}
return cb(sk, head, skb);
}
static inline unsigned int skb_gro_offset(const struct sk_buff *skb)
{
return NAPI_GRO_CB(skb)->data_offset;
}
static inline unsigned int skb_gro_len(const struct sk_buff *skb)
{
return skb->len - NAPI_GRO_CB(skb)->data_offset;
}
static inline void skb_gro_pull(struct sk_buff *skb, unsigned int len)
{
NAPI_GRO_CB(skb)->data_offset += len;
}
static inline void *skb_gro_header_fast(struct sk_buff *skb,
unsigned int offset)
{
return NAPI_GRO_CB(skb)->frag0 + offset;
}
static inline int skb_gro_header_hard(struct sk_buff *skb, unsigned int hlen)
{
return NAPI_GRO_CB(skb)->frag0_len < hlen;
}
static inline void skb_gro_frag0_invalidate(struct sk_buff *skb)
{
NAPI_GRO_CB(skb)->frag0 = NULL;
NAPI_GRO_CB(skb)->frag0_len = 0;
}
static inline void *skb_gro_header_slow(struct sk_buff *skb, unsigned int hlen,
unsigned int offset)
{
if (!pskb_may_pull(skb, hlen))
return NULL;
skb_gro_frag0_invalidate(skb);
return skb->data + offset;
}
static inline void *skb_gro_network_header(struct sk_buff *skb)
{
return (NAPI_GRO_CB(skb)->frag0 ?: skb->data) +
skb_network_offset(skb);
}
static inline __wsum inet_gro_compute_pseudo(struct sk_buff *skb, int proto)
{
const struct iphdr *iph = skb_gro_network_header(skb);
return csum_tcpudp_nofold(iph->saddr, iph->daddr,
skb_gro_len(skb), proto, 0);
}
static inline void skb_gro_postpull_rcsum(struct sk_buff *skb,
const void *start, unsigned int len)
{
if (NAPI_GRO_CB(skb)->csum_valid)
NAPI_GRO_CB(skb)->csum = csum_sub(NAPI_GRO_CB(skb)->csum,
csum_partial(start, len, 0));
}
/* GRO checksum functions. These are logical equivalents of the normal
* checksum functions (in skbuff.h) except that they operate on the GRO
* offsets and fields in sk_buff.
*/
__sum16 __skb_gro_checksum_complete(struct sk_buff *skb);
static inline bool skb_at_gro_remcsum_start(struct sk_buff *skb)
{
return (NAPI_GRO_CB(skb)->gro_remcsum_start == skb_gro_offset(skb));
}
static inline bool __skb_gro_checksum_validate_needed(struct sk_buff *skb,
bool zero_okay,
__sum16 check)
{
return ((skb->ip_summed != CHECKSUM_PARTIAL ||
skb_checksum_start_offset(skb) <
skb_gro_offset(skb)) &&
!skb_at_gro_remcsum_start(skb) &&
NAPI_GRO_CB(skb)->csum_cnt == 0 &&
(!zero_okay || check));
}
static inline __sum16 __skb_gro_checksum_validate_complete(struct sk_buff *skb,
__wsum psum)
{
if (NAPI_GRO_CB(skb)->csum_valid &&
!csum_fold(csum_add(psum, NAPI_GRO_CB(skb)->csum)))
return 0;
NAPI_GRO_CB(skb)->csum = psum;
return __skb_gro_checksum_complete(skb);
}
static inline void skb_gro_incr_csum_unnecessary(struct sk_buff *skb)
{
if (NAPI_GRO_CB(skb)->csum_cnt > 0) {
/* Consume a checksum from CHECKSUM_UNNECESSARY */
NAPI_GRO_CB(skb)->csum_cnt--;
} else {
/* Update skb for CHECKSUM_UNNECESSARY and csum_level when we
* verified a new top level checksum or an encapsulated one
* during GRO. This saves work if we fallback to normal path.
*/
__skb_incr_checksum_unnecessary(skb);
}
}
#define __skb_gro_checksum_validate(skb, proto, zero_okay, check, \
compute_pseudo) \
({ \
__sum16 __ret = 0; \
if (__skb_gro_checksum_validate_needed(skb, zero_okay, check)) \
__ret = __skb_gro_checksum_validate_complete(skb, \
compute_pseudo(skb, proto)); \
if (!__ret) \
skb_gro_incr_csum_unnecessary(skb); \
__ret; \
})
#define skb_gro_checksum_validate(skb, proto, compute_pseudo) \
__skb_gro_checksum_validate(skb, proto, false, 0, compute_pseudo)
#define skb_gro_checksum_validate_zero_check(skb, proto, check, \
compute_pseudo) \
__skb_gro_checksum_validate(skb, proto, true, check, compute_pseudo)
#define skb_gro_checksum_simple_validate(skb) \
__skb_gro_checksum_validate(skb, 0, false, 0, null_compute_pseudo)
static inline bool __skb_gro_checksum_convert_check(struct sk_buff *skb)
{
return (NAPI_GRO_CB(skb)->csum_cnt == 0 &&
!NAPI_GRO_CB(skb)->csum_valid);
}
static inline void __skb_gro_checksum_convert(struct sk_buff *skb,
__wsum pseudo)
{
NAPI_GRO_CB(skb)->csum = ~pseudo;
NAPI_GRO_CB(skb)->csum_valid = 1;
}
#define skb_gro_checksum_try_convert(skb, proto, compute_pseudo) \
do { \
if (__skb_gro_checksum_convert_check(skb)) \
__skb_gro_checksum_convert(skb, \
compute_pseudo(skb, proto)); \
} while (0)
struct gro_remcsum {
int offset;
__wsum delta;
};
static inline void skb_gro_remcsum_init(struct gro_remcsum *grc)
{
grc->offset = 0;
grc->delta = 0;
}
static inline void *skb_gro_remcsum_process(struct sk_buff *skb, void *ptr,
unsigned int off, size_t hdrlen,
int start, int offset,
struct gro_remcsum *grc,
bool nopartial)
{
__wsum delta;
size_t plen = hdrlen + max_t(size_t, offset + sizeof(u16), start);
BUG_ON(!NAPI_GRO_CB(skb)->csum_valid);
if (!nopartial) {
NAPI_GRO_CB(skb)->gro_remcsum_start = off + hdrlen + start;
return ptr;
}
ptr = skb_gro_header_fast(skb, off);
if (skb_gro_header_hard(skb, off + plen)) {
ptr = skb_gro_header_slow(skb, off + plen, off);
if (!ptr)
return NULL;
}
delta = remcsum_adjust(ptr + hdrlen, NAPI_GRO_CB(skb)->csum,
start, offset);
/* Adjust skb->csum since we changed the packet */
NAPI_GRO_CB(skb)->csum = csum_add(NAPI_GRO_CB(skb)->csum, delta);
grc->offset = off + hdrlen + offset;
grc->delta = delta;
return ptr;
}
static inline void skb_gro_remcsum_cleanup(struct sk_buff *skb,
struct gro_remcsum *grc)
{
void *ptr;
size_t plen = grc->offset + sizeof(u16);
if (!grc->delta)
return;
ptr = skb_gro_header_fast(skb, grc->offset);
if (skb_gro_header_hard(skb, grc->offset + sizeof(u16))) {
ptr = skb_gro_header_slow(skb, plen, grc->offset);
if (!ptr)
return;
}
remcsum_unadjust((__sum16 *)ptr, grc->delta);
}
#ifdef CONFIG_XFRM_OFFLOAD
static inline void skb_gro_flush_final(struct sk_buff *skb, struct sk_buff *pp, int flush)
{
if (PTR_ERR(pp) != -EINPROGRESS)
NAPI_GRO_CB(skb)->flush |= flush;
}
static inline void skb_gro_flush_final_remcsum(struct sk_buff *skb,
struct sk_buff *pp,
int flush,
struct gro_remcsum *grc)
{
if (PTR_ERR(pp) != -EINPROGRESS) {
NAPI_GRO_CB(skb)->flush |= flush;
skb_gro_remcsum_cleanup(skb, grc);
skb->remcsum_offload = 0;
}
}
#else
static inline void skb_gro_flush_final(struct sk_buff *skb, struct sk_buff *pp, int flush)
{
NAPI_GRO_CB(skb)->flush |= flush;
}
static inline void skb_gro_flush_final_remcsum(struct sk_buff *skb,
struct sk_buff *pp,
int flush,
struct gro_remcsum *grc)
{
NAPI_GRO_CB(skb)->flush |= flush;
skb_gro_remcsum_cleanup(skb, grc);
skb->remcsum_offload = 0;
}
#endif
INDIRECT_CALLABLE_DECLARE(struct sk_buff *ipv6_gro_receive(struct list_head *,
struct sk_buff *));
INDIRECT_CALLABLE_DECLARE(int ipv6_gro_complete(struct sk_buff *, int));
INDIRECT_CALLABLE_DECLARE(struct sk_buff *inet_gro_receive(struct list_head *,
struct sk_buff *));
INDIRECT_CALLABLE_DECLARE(int inet_gro_complete(struct sk_buff *, int));
INDIRECT_CALLABLE_DECLARE(struct sk_buff *udp4_gro_receive(struct list_head *,
struct sk_buff *));
INDIRECT_CALLABLE_DECLARE(int udp4_gro_complete(struct sk_buff *, int));
INDIRECT_CALLABLE_DECLARE(struct sk_buff *udp6_gro_receive(struct list_head *,
struct sk_buff *));
INDIRECT_CALLABLE_DECLARE(int udp6_gro_complete(struct sk_buff *, int));
#define indirect_call_gro_receive_inet(cb, f2, f1, head, skb) \
({ \
unlikely(gro_recursion_inc_test(skb)) ? \
NAPI_GRO_CB(skb)->flush |= 1, NULL : \
INDIRECT_CALL_INET(cb, f2, f1, head, skb); \
})
struct sk_buff *udp_gro_receive(struct list_head *head, struct sk_buff *skb,
struct udphdr *uh, struct sock *sk);
int udp_gro_complete(struct sk_buff *skb, int nhoff, udp_lookup_t lookup);
static inline struct udphdr *udp_gro_udphdr(struct sk_buff *skb)
{
struct udphdr *uh;
unsigned int hlen, off;
off = skb_gro_offset(skb);
hlen = off + sizeof(*uh);
uh = skb_gro_header_fast(skb, off);
if (skb_gro_header_hard(skb, hlen))
uh = skb_gro_header_slow(skb, hlen, off);
return uh;
}
static inline __wsum ip6_gro_compute_pseudo(struct sk_buff *skb, int proto)
{
const struct ipv6hdr *iph = skb_gro_network_header(skb);
return ~csum_unfold(csum_ipv6_magic(&iph->saddr, &iph->daddr,
skb_gro_len(skb), proto, 0));
}
#endif /* _NET_IPV6_GRO_H */
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