1 /* SPDX-License-Identifier: GPL-2.0-or-later */
3 * Definitions for the 'struct sk_buff' memory handlers.
6 * Alan Cox, <gw4pts@gw4pts.ampr.org>
7 * Florian La Roche, <rzsfl@rz.uni-sb.de>
10 #ifndef _LINUX_SKBUFF_H
11 #define _LINUX_SKBUFF_H
13 #include <linux/kernel.h>
14 #include <linux/compiler.h>
15 #include <linux/time.h>
16 #include <linux/bug.h>
17 #include <linux/bvec.h>
18 #include <linux/cache.h>
19 #include <linux/rbtree.h>
20 #include <linux/socket.h>
21 #include <linux/refcount.h>
23 #include <linux/atomic.h>
24 #include <asm/types.h>
25 #include <linux/spinlock.h>
26 #include <linux/net.h>
27 #include <linux/textsearch.h>
28 #include <net/checksum.h>
29 #include <linux/rcupdate.h>
30 #include <linux/hrtimer.h>
31 #include <linux/dma-mapping.h>
32 #include <linux/netdev_features.h>
33 #include <linux/sched.h>
34 #include <linux/sched/clock.h>
35 #include <net/flow_dissector.h>
36 #include <linux/splice.h>
37 #include <linux/in6.h>
38 #include <linux/if_packet.h>
40 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
41 #include <linux/netfilter/nf_conntrack_common.h>
44 /* The interface for checksum offload between the stack and networking drivers
47 * A. IP checksum related features
49 * Drivers advertise checksum offload capabilities in the features of a device.
50 * From the stack's point of view these are capabilities offered by the driver,
51 * a driver typically only advertises features that it is capable of offloading
54 * The checksum related features are:
56 * NETIF_F_HW_CSUM - The driver (or its device) is able to compute one
57 * IP (one's complement) checksum for any combination
58 * of protocols or protocol layering. The checksum is
59 * computed and set in a packet per the CHECKSUM_PARTIAL
60 * interface (see below).
62 * NETIF_F_IP_CSUM - Driver (device) is only able to checksum plain
63 * TCP or UDP packets over IPv4. These are specifically
64 * unencapsulated packets of the form IPv4|TCP or
65 * IPv4|UDP where the Protocol field in the IPv4 header
66 * is TCP or UDP. The IPv4 header may contain IP options
67 * This feature cannot be set in features for a device
68 * with NETIF_F_HW_CSUM also set. This feature is being
69 * DEPRECATED (see below).
71 * NETIF_F_IPV6_CSUM - Driver (device) is only able to checksum plain
72 * TCP or UDP packets over IPv6. These are specifically
73 * unencapsulated packets of the form IPv6|TCP or
74 * IPv4|UDP where the Next Header field in the IPv6
75 * header is either TCP or UDP. IPv6 extension headers
76 * are not supported with this feature. This feature
77 * cannot be set in features for a device with
78 * NETIF_F_HW_CSUM also set. This feature is being
79 * DEPRECATED (see below).
81 * NETIF_F_RXCSUM - Driver (device) performs receive checksum offload.
82 * This flag is used only used to disable the RX checksum
83 * feature for a device. The stack will accept receive
84 * checksum indication in packets received on a device
85 * regardless of whether NETIF_F_RXCSUM is set.
87 * B. Checksumming of received packets by device. Indication of checksum
88 * verification is in set skb->ip_summed. Possible values are:
92 * Device did not checksum this packet e.g. due to lack of capabilities.
93 * The packet contains full (though not verified) checksum in packet but
94 * not in skb->csum. Thus, skb->csum is undefined in this case.
96 * CHECKSUM_UNNECESSARY:
98 * The hardware you're dealing with doesn't calculate the full checksum
99 * (as in CHECKSUM_COMPLETE), but it does parse headers and verify checksums
100 * for specific protocols. For such packets it will set CHECKSUM_UNNECESSARY
101 * if their checksums are okay. skb->csum is still undefined in this case
102 * though. A driver or device must never modify the checksum field in the
103 * packet even if checksum is verified.
105 * CHECKSUM_UNNECESSARY is applicable to following protocols:
106 * TCP: IPv6 and IPv4.
107 * UDP: IPv4 and IPv6. A device may apply CHECKSUM_UNNECESSARY to a
108 * zero UDP checksum for either IPv4 or IPv6, the networking stack
109 * may perform further validation in this case.
110 * GRE: only if the checksum is present in the header.
111 * SCTP: indicates the CRC in SCTP header has been validated.
112 * FCOE: indicates the CRC in FC frame has been validated.
114 * skb->csum_level indicates the number of consecutive checksums found in
115 * the packet minus one that have been verified as CHECKSUM_UNNECESSARY.
116 * For instance if a device receives an IPv6->UDP->GRE->IPv4->TCP packet
117 * and a device is able to verify the checksums for UDP (possibly zero),
118 * GRE (checksum flag is set), and TCP-- skb->csum_level would be set to
119 * two. If the device were only able to verify the UDP checksum and not
120 * GRE, either because it doesn't support GRE checksum of because GRE
121 * checksum is bad, skb->csum_level would be set to zero (TCP checksum is
122 * not considered in this case).
126 * This is the most generic way. The device supplied checksum of the _whole_
127 * packet as seen by netif_rx() and fills out in skb->csum. Meaning, the
128 * hardware doesn't need to parse L3/L4 headers to implement this.
131 * - Even if device supports only some protocols, but is able to produce
132 * skb->csum, it MUST use CHECKSUM_COMPLETE, not CHECKSUM_UNNECESSARY.
133 * - CHECKSUM_COMPLETE is not applicable to SCTP and FCoE protocols.
137 * A checksum is set up to be offloaded to a device as described in the
138 * output description for CHECKSUM_PARTIAL. This may occur on a packet
139 * received directly from another Linux OS, e.g., a virtualized Linux kernel
140 * on the same host, or it may be set in the input path in GRO or remote
141 * checksum offload. For the purposes of checksum verification, the checksum
142 * referred to by skb->csum_start + skb->csum_offset and any preceding
143 * checksums in the packet are considered verified. Any checksums in the
144 * packet that are after the checksum being offloaded are not considered to
147 * C. Checksumming on transmit for non-GSO. The stack requests checksum offload
148 * in the skb->ip_summed for a packet. Values are:
152 * The driver is required to checksum the packet as seen by hard_start_xmit()
153 * from skb->csum_start up to the end, and to record/write the checksum at
154 * offset skb->csum_start + skb->csum_offset. A driver may verify that the
155 * csum_start and csum_offset values are valid values given the length and
156 * offset of the packet, however they should not attempt to validate that the
157 * checksum refers to a legitimate transport layer checksum-- it is the
158 * purview of the stack to validate that csum_start and csum_offset are set
161 * When the stack requests checksum offload for a packet, the driver MUST
162 * ensure that the checksum is set correctly. A driver can either offload the
163 * checksum calculation to the device, or call skb_checksum_help (in the case
164 * that the device does not support offload for a particular checksum).
166 * NETIF_F_IP_CSUM and NETIF_F_IPV6_CSUM are being deprecated in favor of
167 * NETIF_F_HW_CSUM. New devices should use NETIF_F_HW_CSUM to indicate
168 * checksum offload capability.
169 * skb_csum_hwoffload_help() can be called to resolve CHECKSUM_PARTIAL based
170 * on network device checksumming capabilities: if a packet does not match
171 * them, skb_checksum_help or skb_crc32c_help (depending on the value of
172 * csum_not_inet, see item D.) is called to resolve the checksum.
176 * The skb was already checksummed by the protocol, or a checksum is not
179 * CHECKSUM_UNNECESSARY:
181 * This has the same meaning on as CHECKSUM_NONE for checksum offload on
185 * Not used in checksum output. If a driver observes a packet with this value
186 * set in skbuff, if should treat as CHECKSUM_NONE being set.
188 * D. Non-IP checksum (CRC) offloads
190 * NETIF_F_SCTP_CRC - This feature indicates that a device is capable of
191 * offloading the SCTP CRC in a packet. To perform this offload the stack
192 * will set set csum_start and csum_offset accordingly, set ip_summed to
193 * CHECKSUM_PARTIAL and set csum_not_inet to 1, to provide an indication in
194 * the skbuff that the CHECKSUM_PARTIAL refers to CRC32c.
195 * A driver that supports both IP checksum offload and SCTP CRC32c offload
196 * must verify which offload is configured for a packet by testing the
197 * value of skb->csum_not_inet; skb_crc32c_csum_help is provided to resolve
198 * CHECKSUM_PARTIAL on skbs where csum_not_inet is set to 1.
200 * NETIF_F_FCOE_CRC - This feature indicates that a device is capable of
201 * offloading the FCOE CRC in a packet. To perform this offload the stack
202 * will set ip_summed to CHECKSUM_PARTIAL and set csum_start and csum_offset
203 * accordingly. Note the there is no indication in the skbuff that the
204 * CHECKSUM_PARTIAL refers to an FCOE checksum, a driver that supports
205 * both IP checksum offload and FCOE CRC offload must verify which offload
206 * is configured for a packet presumably by inspecting packet headers.
208 * E. Checksumming on output with GSO.
210 * In the case of a GSO packet (skb_is_gso(skb) is true), checksum offload
211 * is implied by the SKB_GSO_* flags in gso_type. Most obviously, if the
212 * gso_type is SKB_GSO_TCPV4 or SKB_GSO_TCPV6, TCP checksum offload as
213 * part of the GSO operation is implied. If a checksum is being offloaded
214 * with GSO then ip_summed is CHECKSUM_PARTIAL, csum_start and csum_offset
215 * are set to refer to the outermost checksum being offload (two offloaded
216 * checksums are possible with UDP encapsulation).
219 /* Don't change this without changing skb_csum_unnecessary! */
220 #define CHECKSUM_NONE 0
221 #define CHECKSUM_UNNECESSARY 1
222 #define CHECKSUM_COMPLETE 2
223 #define CHECKSUM_PARTIAL 3
225 /* Maximum value in skb->csum_level */
226 #define SKB_MAX_CSUM_LEVEL 3
228 #define SKB_DATA_ALIGN(X) ALIGN(X, SMP_CACHE_BYTES)
229 #define SKB_WITH_OVERHEAD(X) \
230 ((X) - SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
231 #define SKB_MAX_ORDER(X, ORDER) \
232 SKB_WITH_OVERHEAD((PAGE_SIZE << (ORDER)) - (X))
233 #define SKB_MAX_HEAD(X) (SKB_MAX_ORDER((X), 0))
234 #define SKB_MAX_ALLOC (SKB_MAX_ORDER(0, 2))
236 /* return minimum truesize of one skb containing X bytes of data */
237 #define SKB_TRUESIZE(X) ((X) + \
238 SKB_DATA_ALIGN(sizeof(struct sk_buff)) + \
239 SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
243 struct pipe_inode_info
;
250 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
251 struct nf_bridge_info
{
253 BRNF_PROTO_UNCHANGED
,
261 struct net_device
*physindev
;
263 /* always valid & non-NULL from FORWARD on, for physdev match */
264 struct net_device
*physoutdev
;
266 /* prerouting: detect dnat in orig/reply direction */
268 struct in6_addr ipv6_daddr
;
270 /* after prerouting + nat detected: store original source
271 * mac since neigh resolution overwrites it, only used while
272 * skb is out in neigh layer.
274 char neigh_header
[8];
279 #if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
280 /* Chain in tc_skb_ext will be used to share the tc chain with
281 * ovs recirc_id. It will be set to the current chain by tc
282 * and read by ovs to recirc_id.
289 struct sk_buff_head
{
290 /* These two members must be first. */
291 struct sk_buff
*next
;
292 struct sk_buff
*prev
;
300 /* To allow 64K frame to be packed as single skb without frag_list we
301 * require 64K/PAGE_SIZE pages plus 1 additional page to allow for
302 * buffers which do not start on a page boundary.
304 * Since GRO uses frags we allocate at least 16 regardless of page
307 #if (65536/PAGE_SIZE + 1) < 16
308 #define MAX_SKB_FRAGS 16UL
310 #define MAX_SKB_FRAGS (65536/PAGE_SIZE + 1)
312 extern int sysctl_max_skb_frags
;
314 /* Set skb_shinfo(skb)->gso_size to this in case you want skb_segment to
315 * segment using its current segmentation instead.
317 #define GSO_BY_FRAGS 0xFFFF
319 typedef struct bio_vec skb_frag_t
;
322 * skb_frag_size() - Returns the size of a skb fragment
323 * @frag: skb fragment
325 static inline unsigned int skb_frag_size(const skb_frag_t
*frag
)
331 * skb_frag_size_set() - Sets the size of a skb fragment
332 * @frag: skb fragment
333 * @size: size of fragment
335 static inline void skb_frag_size_set(skb_frag_t
*frag
, unsigned int size
)
341 * skb_frag_size_add() - Increments the size of a skb fragment by @delta
342 * @frag: skb fragment
343 * @delta: value to add
345 static inline void skb_frag_size_add(skb_frag_t
*frag
, int delta
)
347 frag
->bv_len
+= delta
;
351 * skb_frag_size_sub() - Decrements the size of a skb fragment by @delta
352 * @frag: skb fragment
353 * @delta: value to subtract
355 static inline void skb_frag_size_sub(skb_frag_t
*frag
, int delta
)
357 frag
->bv_len
-= delta
;
361 * skb_frag_must_loop - Test if %p is a high memory page
362 * @p: fragment's page
364 static inline bool skb_frag_must_loop(struct page
*p
)
366 #if defined(CONFIG_HIGHMEM)
374 * skb_frag_foreach_page - loop over pages in a fragment
376 * @f: skb frag to operate on
377 * @f_off: offset from start of f->bv_page
378 * @f_len: length from f_off to loop over
379 * @p: (temp var) current page
380 * @p_off: (temp var) offset from start of current page,
381 * non-zero only on first page.
382 * @p_len: (temp var) length in current page,
383 * < PAGE_SIZE only on first and last page.
384 * @copied: (temp var) length so far, excluding current p_len.
386 * A fragment can hold a compound page, in which case per-page
387 * operations, notably kmap_atomic, must be called for each
390 #define skb_frag_foreach_page(f, f_off, f_len, p, p_off, p_len, copied) \
391 for (p = skb_frag_page(f) + ((f_off) >> PAGE_SHIFT), \
392 p_off = (f_off) & (PAGE_SIZE - 1), \
393 p_len = skb_frag_must_loop(p) ? \
394 min_t(u32, f_len, PAGE_SIZE - p_off) : f_len, \
397 copied += p_len, p++, p_off = 0, \
398 p_len = min_t(u32, f_len - copied, PAGE_SIZE)) \
400 #define HAVE_HW_TIME_STAMP
403 * struct skb_shared_hwtstamps - hardware time stamps
404 * @hwtstamp: hardware time stamp transformed into duration
405 * since arbitrary point in time
407 * Software time stamps generated by ktime_get_real() are stored in
410 * hwtstamps can only be compared against other hwtstamps from
413 * This structure is attached to packets as part of the
414 * &skb_shared_info. Use skb_hwtstamps() to get a pointer.
416 struct skb_shared_hwtstamps
{
420 /* Definitions for tx_flags in struct skb_shared_info */
422 /* generate hardware time stamp */
423 SKBTX_HW_TSTAMP
= 1 << 0,
425 /* generate software time stamp when queueing packet to NIC */
426 SKBTX_SW_TSTAMP
= 1 << 1,
428 /* device driver is going to provide hardware time stamp */
429 SKBTX_IN_PROGRESS
= 1 << 2,
431 /* device driver supports TX zero-copy buffers */
432 SKBTX_DEV_ZEROCOPY
= 1 << 3,
434 /* generate wifi status information (where possible) */
435 SKBTX_WIFI_STATUS
= 1 << 4,
437 /* This indicates at least one fragment might be overwritten
438 * (as in vmsplice(), sendfile() ...)
439 * If we need to compute a TX checksum, we'll need to copy
440 * all frags to avoid possible bad checksum
442 SKBTX_SHARED_FRAG
= 1 << 5,
444 /* generate software time stamp when entering packet scheduling */
445 SKBTX_SCHED_TSTAMP
= 1 << 6,
448 #define SKBTX_ZEROCOPY_FRAG (SKBTX_DEV_ZEROCOPY | SKBTX_SHARED_FRAG)
449 #define SKBTX_ANY_SW_TSTAMP (SKBTX_SW_TSTAMP | \
451 #define SKBTX_ANY_TSTAMP (SKBTX_HW_TSTAMP | SKBTX_ANY_SW_TSTAMP)
454 * The callback notifies userspace to release buffers when skb DMA is done in
455 * lower device, the skb last reference should be 0 when calling this.
456 * The zerocopy_success argument is true if zero copy transmit occurred,
457 * false on data copy or out of memory error caused by data copy attempt.
458 * The ctx field is used to track device context.
459 * The desc field is used to track userspace buffer index.
462 void (*callback
)(struct ubuf_info
*, bool zerocopy_success
);
478 struct user_struct
*user
;
483 #define skb_uarg(SKB) ((struct ubuf_info *)(skb_shinfo(SKB)->destructor_arg))
485 int mm_account_pinned_pages(struct mmpin
*mmp
, size_t size
);
486 void mm_unaccount_pinned_pages(struct mmpin
*mmp
);
488 struct ubuf_info
*sock_zerocopy_alloc(struct sock
*sk
, size_t size
);
489 struct ubuf_info
*sock_zerocopy_realloc(struct sock
*sk
, size_t size
,
490 struct ubuf_info
*uarg
);
492 static inline void sock_zerocopy_get(struct ubuf_info
*uarg
)
494 refcount_inc(&uarg
->refcnt
);
497 void sock_zerocopy_put(struct ubuf_info
*uarg
);
498 void sock_zerocopy_put_abort(struct ubuf_info
*uarg
, bool have_uref
);
500 void sock_zerocopy_callback(struct ubuf_info
*uarg
, bool success
);
502 int skb_zerocopy_iter_dgram(struct sk_buff
*skb
, struct msghdr
*msg
, int len
);
503 int skb_zerocopy_iter_stream(struct sock
*sk
, struct sk_buff
*skb
,
504 struct msghdr
*msg
, int len
,
505 struct ubuf_info
*uarg
);
507 /* This data is invariant across clones and lives at
508 * the end of the header data, ie. at skb->end.
510 struct skb_shared_info
{
515 unsigned short gso_size
;
516 /* Warning: this field is not always filled in (UFO)! */
517 unsigned short gso_segs
;
518 struct sk_buff
*frag_list
;
519 struct skb_shared_hwtstamps hwtstamps
;
520 unsigned int gso_type
;
524 * Warning : all fields before dataref are cleared in __alloc_skb()
528 /* Intermediate layers must ensure that destructor_arg
529 * remains valid until skb destructor */
530 void * destructor_arg
;
532 /* must be last field, see pskb_expand_head() */
533 skb_frag_t frags
[MAX_SKB_FRAGS
];
536 /* We divide dataref into two halves. The higher 16 bits hold references
537 * to the payload part of skb->data. The lower 16 bits hold references to
538 * the entire skb->data. A clone of a headerless skb holds the length of
539 * the header in skb->hdr_len.
541 * All users must obey the rule that the skb->data reference count must be
542 * greater than or equal to the payload reference count.
544 * Holding a reference to the payload part means that the user does not
545 * care about modifications to the header part of skb->data.
547 #define SKB_DATAREF_SHIFT 16
548 #define SKB_DATAREF_MASK ((1 << SKB_DATAREF_SHIFT) - 1)
552 SKB_FCLONE_UNAVAILABLE
, /* skb has no fclone (from head_cache) */
553 SKB_FCLONE_ORIG
, /* orig skb (from fclone_cache) */
554 SKB_FCLONE_CLONE
, /* companion fclone skb (from fclone_cache) */
558 SKB_GSO_TCPV4
= 1 << 0,
560 /* This indicates the skb is from an untrusted source. */
561 SKB_GSO_DODGY
= 1 << 1,
563 /* This indicates the tcp segment has CWR set. */
564 SKB_GSO_TCP_ECN
= 1 << 2,
566 SKB_GSO_TCP_FIXEDID
= 1 << 3,
568 SKB_GSO_TCPV6
= 1 << 4,
570 SKB_GSO_FCOE
= 1 << 5,
572 SKB_GSO_GRE
= 1 << 6,
574 SKB_GSO_GRE_CSUM
= 1 << 7,
576 SKB_GSO_IPXIP4
= 1 << 8,
578 SKB_GSO_IPXIP6
= 1 << 9,
580 SKB_GSO_UDP_TUNNEL
= 1 << 10,
582 SKB_GSO_UDP_TUNNEL_CSUM
= 1 << 11,
584 SKB_GSO_PARTIAL
= 1 << 12,
586 SKB_GSO_TUNNEL_REMCSUM
= 1 << 13,
588 SKB_GSO_SCTP
= 1 << 14,
590 SKB_GSO_ESP
= 1 << 15,
592 SKB_GSO_UDP
= 1 << 16,
594 SKB_GSO_UDP_L4
= 1 << 17,
597 #if BITS_PER_LONG > 32
598 #define NET_SKBUFF_DATA_USES_OFFSET 1
601 #ifdef NET_SKBUFF_DATA_USES_OFFSET
602 typedef unsigned int sk_buff_data_t
;
604 typedef unsigned char *sk_buff_data_t
;
608 * struct sk_buff - socket buffer
609 * @next: Next buffer in list
610 * @prev: Previous buffer in list
611 * @tstamp: Time we arrived/left
612 * @rbnode: RB tree node, alternative to next/prev for netem/tcp
613 * @sk: Socket we are owned by
614 * @dev: Device we arrived on/are leaving by
615 * @cb: Control buffer. Free for use by every layer. Put private vars here
616 * @_skb_refdst: destination entry (with norefcount bit)
617 * @sp: the security path, used for xfrm
618 * @len: Length of actual data
619 * @data_len: Data length
620 * @mac_len: Length of link layer header
621 * @hdr_len: writable header length of cloned skb
622 * @csum: Checksum (must include start/offset pair)
623 * @csum_start: Offset from skb->head where checksumming should start
624 * @csum_offset: Offset from csum_start where checksum should be stored
625 * @priority: Packet queueing priority
626 * @ignore_df: allow local fragmentation
627 * @cloned: Head may be cloned (check refcnt to be sure)
628 * @ip_summed: Driver fed us an IP checksum
629 * @nohdr: Payload reference only, must not modify header
630 * @pkt_type: Packet class
631 * @fclone: skbuff clone status
632 * @ipvs_property: skbuff is owned by ipvs
633 * @offload_fwd_mark: Packet was L2-forwarded in hardware
634 * @offload_l3_fwd_mark: Packet was L3-forwarded in hardware
635 * @tc_skip_classify: do not classify packet. set by IFB device
636 * @tc_at_ingress: used within tc_classify to distinguish in/egress
637 * @tc_redirected: packet was redirected by a tc action
638 * @tc_from_ingress: if tc_redirected, tc_at_ingress at time of redirect
639 * @peeked: this packet has been seen already, so stats have been
640 * done for it, don't do them again
641 * @nf_trace: netfilter packet trace flag
642 * @protocol: Packet protocol from driver
643 * @destructor: Destruct function
644 * @tcp_tsorted_anchor: list structure for TCP (tp->tsorted_sent_queue)
645 * @_nfct: Associated connection, if any (with nfctinfo bits)
646 * @nf_bridge: Saved data about a bridged frame - see br_netfilter.c
647 * @skb_iif: ifindex of device we arrived on
648 * @tc_index: Traffic control index
649 * @hash: the packet hash
650 * @queue_mapping: Queue mapping for multiqueue devices
651 * @pfmemalloc: skbuff was allocated from PFMEMALLOC reserves
652 * @active_extensions: active extensions (skb_ext_id types)
653 * @ndisc_nodetype: router type (from link layer)
654 * @ooo_okay: allow the mapping of a socket to a queue to be changed
655 * @l4_hash: indicate hash is a canonical 4-tuple hash over transport
657 * @sw_hash: indicates hash was computed in software stack
658 * @wifi_acked_valid: wifi_acked was set
659 * @wifi_acked: whether frame was acked on wifi or not
660 * @no_fcs: Request NIC to treat last 4 bytes as Ethernet FCS
661 * @csum_not_inet: use CRC32c to resolve CHECKSUM_PARTIAL
662 * @dst_pending_confirm: need to confirm neighbour
663 * @decrypted: Decrypted SKB
664 * @napi_id: id of the NAPI struct this skb came from
665 * @secmark: security marking
666 * @mark: Generic packet mark
667 * @vlan_proto: vlan encapsulation protocol
668 * @vlan_tci: vlan tag control information
669 * @inner_protocol: Protocol (encapsulation)
670 * @inner_transport_header: Inner transport layer header (encapsulation)
671 * @inner_network_header: Network layer header (encapsulation)
672 * @inner_mac_header: Link layer header (encapsulation)
673 * @transport_header: Transport layer header
674 * @network_header: Network layer header
675 * @mac_header: Link layer header
676 * @tail: Tail pointer
678 * @head: Head of buffer
679 * @data: Data head pointer
680 * @truesize: Buffer size
681 * @users: User count - see {datagram,tcp}.c
682 * @extensions: allocated extensions, valid if active_extensions is nonzero
688 /* These two members must be first. */
689 struct sk_buff
*next
;
690 struct sk_buff
*prev
;
693 struct net_device
*dev
;
694 /* Some protocols might use this space to store information,
695 * while device pointer would be NULL.
696 * UDP receive path is one user.
698 unsigned long dev_scratch
;
701 struct rb_node rbnode
; /* used in netem, ip4 defrag, and tcp stack */
702 struct list_head list
;
707 int ip_defrag_offset
;
712 u64 skb_mstamp_ns
; /* earliest departure time */
715 * This is the control buffer. It is free to use for every
716 * layer. Please put your private variables there. If you
717 * want to keep them across layers you have to do a skb_clone()
718 * first. This is owned by whoever has the skb queued ATM.
720 char cb
[48] __aligned(8);
724 unsigned long _skb_refdst
;
725 void (*destructor
)(struct sk_buff
*skb
);
727 struct list_head tcp_tsorted_anchor
;
730 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
738 /* Following fields are _not_ copied in __copy_skb_header()
739 * Note that queue_mapping is here mostly to fill a hole.
743 /* if you move cloned around you also must adapt those constants */
744 #ifdef __BIG_ENDIAN_BITFIELD
745 #define CLONED_MASK (1 << 7)
747 #define CLONED_MASK 1
749 #define CLONED_OFFSET() offsetof(struct sk_buff, __cloned_offset)
751 __u8 __cloned_offset
[0];
758 #ifdef CONFIG_SKB_EXTENSIONS
759 __u8 active_extensions
;
761 /* fields enclosed in headers_start/headers_end are copied
762 * using a single memcpy() in __copy_skb_header()
765 __u32 headers_start
[0];
768 /* if you move pkt_type around you also must adapt those constants */
769 #ifdef __BIG_ENDIAN_BITFIELD
770 #define PKT_TYPE_MAX (7 << 5)
772 #define PKT_TYPE_MAX 7
774 #define PKT_TYPE_OFFSET() offsetof(struct sk_buff, __pkt_type_offset)
776 __u8 __pkt_type_offset
[0];
785 __u8 wifi_acked_valid
:1;
788 /* Indicates the inner headers are valid in the skbuff. */
789 __u8 encapsulation
:1;
790 __u8 encap_hdr_csum
:1;
793 #ifdef __BIG_ENDIAN_BITFIELD
794 #define PKT_VLAN_PRESENT_BIT 7
796 #define PKT_VLAN_PRESENT_BIT 0
798 #define PKT_VLAN_PRESENT_OFFSET() offsetof(struct sk_buff, __pkt_vlan_present_offset)
799 __u8 __pkt_vlan_present_offset
[0];
801 __u8 csum_complete_sw
:1;
803 __u8 csum_not_inet
:1;
804 __u8 dst_pending_confirm
:1;
805 #ifdef CONFIG_IPV6_NDISC_NODETYPE
806 __u8 ndisc_nodetype
:2;
809 __u8 ipvs_property
:1;
810 __u8 inner_protocol_type
:1;
811 __u8 remcsum_offload
:1;
812 #ifdef CONFIG_NET_SWITCHDEV
813 __u8 offload_fwd_mark
:1;
814 __u8 offload_l3_fwd_mark
:1;
816 #ifdef CONFIG_NET_CLS_ACT
817 __u8 tc_skip_classify
:1;
818 __u8 tc_at_ingress
:1;
819 __u8 tc_redirected
:1;
820 __u8 tc_from_ingress
:1;
822 #ifdef CONFIG_TLS_DEVICE
826 #ifdef CONFIG_NET_SCHED
827 __u16 tc_index
; /* traffic control index */
842 #if defined(CONFIG_NET_RX_BUSY_POLL) || defined(CONFIG_XPS)
844 unsigned int napi_id
;
845 unsigned int sender_cpu
;
848 #ifdef CONFIG_NETWORK_SECMARK
854 __u32 reserved_tailroom
;
858 __be16 inner_protocol
;
862 __u16 inner_transport_header
;
863 __u16 inner_network_header
;
864 __u16 inner_mac_header
;
867 __u16 transport_header
;
868 __u16 network_header
;
872 __u32 headers_end
[0];
875 /* These elements must be at the end, see alloc_skb() for details. */
880 unsigned int truesize
;
883 #ifdef CONFIG_SKB_EXTENSIONS
884 /* only useable after checking ->active_extensions != 0 */
885 struct skb_ext
*extensions
;
891 * Handling routines are only of interest to the kernel
894 #define SKB_ALLOC_FCLONE 0x01
895 #define SKB_ALLOC_RX 0x02
896 #define SKB_ALLOC_NAPI 0x04
899 * skb_pfmemalloc - Test if the skb was allocated from PFMEMALLOC reserves
902 static inline bool skb_pfmemalloc(const struct sk_buff
*skb
)
904 return unlikely(skb
->pfmemalloc
);
908 * skb might have a dst pointer attached, refcounted or not.
909 * _skb_refdst low order bit is set if refcount was _not_ taken
911 #define SKB_DST_NOREF 1UL
912 #define SKB_DST_PTRMASK ~(SKB_DST_NOREF)
915 * skb_dst - returns skb dst_entry
918 * Returns skb dst_entry, regardless of reference taken or not.
920 static inline struct dst_entry
*skb_dst(const struct sk_buff
*skb
)
922 /* If refdst was not refcounted, check we still are in a
923 * rcu_read_lock section
925 WARN_ON((skb
->_skb_refdst
& SKB_DST_NOREF
) &&
926 !rcu_read_lock_held() &&
927 !rcu_read_lock_bh_held());
928 return (struct dst_entry
*)(skb
->_skb_refdst
& SKB_DST_PTRMASK
);
932 * skb_dst_set - sets skb dst
936 * Sets skb dst, assuming a reference was taken on dst and should
937 * be released by skb_dst_drop()
939 static inline void skb_dst_set(struct sk_buff
*skb
, struct dst_entry
*dst
)
941 skb
->_skb_refdst
= (unsigned long)dst
;
945 * skb_dst_set_noref - sets skb dst, hopefully, without taking reference
949 * Sets skb dst, assuming a reference was not taken on dst.
950 * If dst entry is cached, we do not take reference and dst_release
951 * will be avoided by refdst_drop. If dst entry is not cached, we take
952 * reference, so that last dst_release can destroy the dst immediately.
954 static inline void skb_dst_set_noref(struct sk_buff
*skb
, struct dst_entry
*dst
)
956 WARN_ON(!rcu_read_lock_held() && !rcu_read_lock_bh_held());
957 skb
->_skb_refdst
= (unsigned long)dst
| SKB_DST_NOREF
;
961 * skb_dst_is_noref - Test if skb dst isn't refcounted
964 static inline bool skb_dst_is_noref(const struct sk_buff
*skb
)
966 return (skb
->_skb_refdst
& SKB_DST_NOREF
) && skb_dst(skb
);
970 * skb_rtable - Returns the skb &rtable
973 static inline struct rtable
*skb_rtable(const struct sk_buff
*skb
)
975 return (struct rtable
*)skb_dst(skb
);
978 /* For mangling skb->pkt_type from user space side from applications
979 * such as nft, tc, etc, we only allow a conservative subset of
980 * possible pkt_types to be set.
982 static inline bool skb_pkt_type_ok(u32 ptype
)
984 return ptype
<= PACKET_OTHERHOST
;
988 * skb_napi_id - Returns the skb's NAPI id
991 static inline unsigned int skb_napi_id(const struct sk_buff
*skb
)
993 #ifdef CONFIG_NET_RX_BUSY_POLL
1001 * skb_unref - decrement the skb's reference count
1004 * Returns true if we can free the skb.
1006 static inline bool skb_unref(struct sk_buff
*skb
)
1010 if (likely(refcount_read(&skb
->users
) == 1))
1012 else if (likely(!refcount_dec_and_test(&skb
->users
)))
1018 void skb_release_head_state(struct sk_buff
*skb
);
1019 void kfree_skb(struct sk_buff
*skb
);
1020 void kfree_skb_list(struct sk_buff
*segs
);
1021 void skb_dump(const char *level
, const struct sk_buff
*skb
, bool full_pkt
);
1022 void skb_tx_error(struct sk_buff
*skb
);
1023 void consume_skb(struct sk_buff
*skb
);
1024 void __consume_stateless_skb(struct sk_buff
*skb
);
1025 void __kfree_skb(struct sk_buff
*skb
);
1026 extern struct kmem_cache
*skbuff_head_cache
;
1028 void kfree_skb_partial(struct sk_buff
*skb
, bool head_stolen
);
1029 bool skb_try_coalesce(struct sk_buff
*to
, struct sk_buff
*from
,
1030 bool *fragstolen
, int *delta_truesize
);
1032 struct sk_buff
*__alloc_skb(unsigned int size
, gfp_t priority
, int flags
,
1034 struct sk_buff
*__build_skb(void *data
, unsigned int frag_size
);
1035 struct sk_buff
*build_skb(void *data
, unsigned int frag_size
);
1036 struct sk_buff
*build_skb_around(struct sk_buff
*skb
,
1037 void *data
, unsigned int frag_size
);
1040 * alloc_skb - allocate a network buffer
1041 * @size: size to allocate
1042 * @priority: allocation mask
1044 * This function is a convenient wrapper around __alloc_skb().
1046 static inline struct sk_buff
*alloc_skb(unsigned int size
,
1049 return __alloc_skb(size
, priority
, 0, NUMA_NO_NODE
);
1052 struct sk_buff
*alloc_skb_with_frags(unsigned long header_len
,
1053 unsigned long data_len
,
1057 struct sk_buff
*alloc_skb_for_msg(struct sk_buff
*first
);
1059 /* Layout of fast clones : [skb1][skb2][fclone_ref] */
1060 struct sk_buff_fclones
{
1061 struct sk_buff skb1
;
1063 struct sk_buff skb2
;
1065 refcount_t fclone_ref
;
1069 * skb_fclone_busy - check if fclone is busy
1073 * Returns true if skb is a fast clone, and its clone is not freed.
1074 * Some drivers call skb_orphan() in their ndo_start_xmit(),
1075 * so we also check that this didnt happen.
1077 static inline bool skb_fclone_busy(const struct sock
*sk
,
1078 const struct sk_buff
*skb
)
1080 const struct sk_buff_fclones
*fclones
;
1082 fclones
= container_of(skb
, struct sk_buff_fclones
, skb1
);
1084 return skb
->fclone
== SKB_FCLONE_ORIG
&&
1085 refcount_read(&fclones
->fclone_ref
) > 1 &&
1086 fclones
->skb2
.sk
== sk
;
1090 * alloc_skb_fclone - allocate a network buffer from fclone cache
1091 * @size: size to allocate
1092 * @priority: allocation mask
1094 * This function is a convenient wrapper around __alloc_skb().
1096 static inline struct sk_buff
*alloc_skb_fclone(unsigned int size
,
1099 return __alloc_skb(size
, priority
, SKB_ALLOC_FCLONE
, NUMA_NO_NODE
);
1102 struct sk_buff
*skb_morph(struct sk_buff
*dst
, struct sk_buff
*src
);
1103 void skb_headers_offset_update(struct sk_buff
*skb
, int off
);
1104 int skb_copy_ubufs(struct sk_buff
*skb
, gfp_t gfp_mask
);
1105 struct sk_buff
*skb_clone(struct sk_buff
*skb
, gfp_t priority
);
1106 void skb_copy_header(struct sk_buff
*new, const struct sk_buff
*old
);
1107 struct sk_buff
*skb_copy(const struct sk_buff
*skb
, gfp_t priority
);
1108 struct sk_buff
*__pskb_copy_fclone(struct sk_buff
*skb
, int headroom
,
1109 gfp_t gfp_mask
, bool fclone
);
1110 static inline struct sk_buff
*__pskb_copy(struct sk_buff
*skb
, int headroom
,
1113 return __pskb_copy_fclone(skb
, headroom
, gfp_mask
, false);
1116 int pskb_expand_head(struct sk_buff
*skb
, int nhead
, int ntail
, gfp_t gfp_mask
);
1117 struct sk_buff
*skb_realloc_headroom(struct sk_buff
*skb
,
1118 unsigned int headroom
);
1119 struct sk_buff
*skb_copy_expand(const struct sk_buff
*skb
, int newheadroom
,
1120 int newtailroom
, gfp_t priority
);
1121 int __must_check
skb_to_sgvec_nomark(struct sk_buff
*skb
, struct scatterlist
*sg
,
1122 int offset
, int len
);
1123 int __must_check
skb_to_sgvec(struct sk_buff
*skb
, struct scatterlist
*sg
,
1124 int offset
, int len
);
1125 int skb_cow_data(struct sk_buff
*skb
, int tailbits
, struct sk_buff
**trailer
);
1126 int __skb_pad(struct sk_buff
*skb
, int pad
, bool free_on_error
);
1129 * skb_pad - zero pad the tail of an skb
1130 * @skb: buffer to pad
1131 * @pad: space to pad
1133 * Ensure that a buffer is followed by a padding area that is zero
1134 * filled. Used by network drivers which may DMA or transfer data
1135 * beyond the buffer end onto the wire.
1137 * May return error in out of memory cases. The skb is freed on error.
1139 static inline int skb_pad(struct sk_buff
*skb
, int pad
)
1141 return __skb_pad(skb
, pad
, true);
1143 #define dev_kfree_skb(a) consume_skb(a)
1145 int skb_append_pagefrags(struct sk_buff
*skb
, struct page
*page
,
1146 int offset
, size_t size
);
1148 struct skb_seq_state
{
1152 __u32 stepped_offset
;
1153 struct sk_buff
*root_skb
;
1154 struct sk_buff
*cur_skb
;
1158 void skb_prepare_seq_read(struct sk_buff
*skb
, unsigned int from
,
1159 unsigned int to
, struct skb_seq_state
*st
);
1160 unsigned int skb_seq_read(unsigned int consumed
, const u8
**data
,
1161 struct skb_seq_state
*st
);
1162 void skb_abort_seq_read(struct skb_seq_state
*st
);
1164 unsigned int skb_find_text(struct sk_buff
*skb
, unsigned int from
,
1165 unsigned int to
, struct ts_config
*config
);
1168 * Packet hash types specify the type of hash in skb_set_hash.
1170 * Hash types refer to the protocol layer addresses which are used to
1171 * construct a packet's hash. The hashes are used to differentiate or identify
1172 * flows of the protocol layer for the hash type. Hash types are either
1173 * layer-2 (L2), layer-3 (L3), or layer-4 (L4).
1175 * Properties of hashes:
1177 * 1) Two packets in different flows have different hash values
1178 * 2) Two packets in the same flow should have the same hash value
1180 * A hash at a higher layer is considered to be more specific. A driver should
1181 * set the most specific hash possible.
1183 * A driver cannot indicate a more specific hash than the layer at which a hash
1184 * was computed. For instance an L3 hash cannot be set as an L4 hash.
1186 * A driver may indicate a hash level which is less specific than the
1187 * actual layer the hash was computed on. For instance, a hash computed
1188 * at L4 may be considered an L3 hash. This should only be done if the
1189 * driver can't unambiguously determine that the HW computed the hash at
1190 * the higher layer. Note that the "should" in the second property above
1193 enum pkt_hash_types
{
1194 PKT_HASH_TYPE_NONE
, /* Undefined type */
1195 PKT_HASH_TYPE_L2
, /* Input: src_MAC, dest_MAC */
1196 PKT_HASH_TYPE_L3
, /* Input: src_IP, dst_IP */
1197 PKT_HASH_TYPE_L4
, /* Input: src_IP, dst_IP, src_port, dst_port */
1200 static inline void skb_clear_hash(struct sk_buff
*skb
)
1207 static inline void skb_clear_hash_if_not_l4(struct sk_buff
*skb
)
1210 skb_clear_hash(skb
);
1214 __skb_set_hash(struct sk_buff
*skb
, __u32 hash
, bool is_sw
, bool is_l4
)
1216 skb
->l4_hash
= is_l4
;
1217 skb
->sw_hash
= is_sw
;
1222 skb_set_hash(struct sk_buff
*skb
, __u32 hash
, enum pkt_hash_types type
)
1224 /* Used by drivers to set hash from HW */
1225 __skb_set_hash(skb
, hash
, false, type
== PKT_HASH_TYPE_L4
);
1229 __skb_set_sw_hash(struct sk_buff
*skb
, __u32 hash
, bool is_l4
)
1231 __skb_set_hash(skb
, hash
, true, is_l4
);
1234 void __skb_get_hash(struct sk_buff
*skb
);
1235 u32
__skb_get_hash_symmetric(const struct sk_buff
*skb
);
1236 u32
skb_get_poff(const struct sk_buff
*skb
);
1237 u32
__skb_get_poff(const struct sk_buff
*skb
, void *data
,
1238 const struct flow_keys_basic
*keys
, int hlen
);
1239 __be32
__skb_flow_get_ports(const struct sk_buff
*skb
, int thoff
, u8 ip_proto
,
1240 void *data
, int hlen_proto
);
1242 static inline __be32
skb_flow_get_ports(const struct sk_buff
*skb
,
1243 int thoff
, u8 ip_proto
)
1245 return __skb_flow_get_ports(skb
, thoff
, ip_proto
, NULL
, 0);
1248 void skb_flow_dissector_init(struct flow_dissector
*flow_dissector
,
1249 const struct flow_dissector_key
*key
,
1250 unsigned int key_count
);
1253 int skb_flow_dissector_prog_query(const union bpf_attr
*attr
,
1254 union bpf_attr __user
*uattr
);
1255 int skb_flow_dissector_bpf_prog_attach(const union bpf_attr
*attr
,
1256 struct bpf_prog
*prog
);
1258 int skb_flow_dissector_bpf_prog_detach(const union bpf_attr
*attr
);
1260 static inline int skb_flow_dissector_prog_query(const union bpf_attr
*attr
,
1261 union bpf_attr __user
*uattr
)
1266 static inline int skb_flow_dissector_bpf_prog_attach(const union bpf_attr
*attr
,
1267 struct bpf_prog
*prog
)
1272 static inline int skb_flow_dissector_bpf_prog_detach(const union bpf_attr
*attr
)
1278 struct bpf_flow_dissector
;
1279 bool bpf_flow_dissect(struct bpf_prog
*prog
, struct bpf_flow_dissector
*ctx
,
1280 __be16 proto
, int nhoff
, int hlen
, unsigned int flags
);
1282 bool __skb_flow_dissect(const struct net
*net
,
1283 const struct sk_buff
*skb
,
1284 struct flow_dissector
*flow_dissector
,
1285 void *target_container
,
1286 void *data
, __be16 proto
, int nhoff
, int hlen
,
1287 unsigned int flags
);
1289 static inline bool skb_flow_dissect(const struct sk_buff
*skb
,
1290 struct flow_dissector
*flow_dissector
,
1291 void *target_container
, unsigned int flags
)
1293 return __skb_flow_dissect(NULL
, skb
, flow_dissector
,
1294 target_container
, NULL
, 0, 0, 0, flags
);
1297 static inline bool skb_flow_dissect_flow_keys(const struct sk_buff
*skb
,
1298 struct flow_keys
*flow
,
1301 memset(flow
, 0, sizeof(*flow
));
1302 return __skb_flow_dissect(NULL
, skb
, &flow_keys_dissector
,
1303 flow
, NULL
, 0, 0, 0, flags
);
1307 skb_flow_dissect_flow_keys_basic(const struct net
*net
,
1308 const struct sk_buff
*skb
,
1309 struct flow_keys_basic
*flow
, void *data
,
1310 __be16 proto
, int nhoff
, int hlen
,
1313 memset(flow
, 0, sizeof(*flow
));
1314 return __skb_flow_dissect(net
, skb
, &flow_keys_basic_dissector
, flow
,
1315 data
, proto
, nhoff
, hlen
, flags
);
1318 void skb_flow_dissect_meta(const struct sk_buff
*skb
,
1319 struct flow_dissector
*flow_dissector
,
1320 void *target_container
);
1322 /* Gets a skb connection tracking info, ctinfo map should be a
1323 * a map of mapsize to translate enum ip_conntrack_info states
1327 skb_flow_dissect_ct(const struct sk_buff
*skb
,
1328 struct flow_dissector
*flow_dissector
,
1329 void *target_container
,
1333 skb_flow_dissect_tunnel_info(const struct sk_buff
*skb
,
1334 struct flow_dissector
*flow_dissector
,
1335 void *target_container
);
1337 static inline __u32
skb_get_hash(struct sk_buff
*skb
)
1339 if (!skb
->l4_hash
&& !skb
->sw_hash
)
1340 __skb_get_hash(skb
);
1345 static inline __u32
skb_get_hash_flowi6(struct sk_buff
*skb
, const struct flowi6
*fl6
)
1347 if (!skb
->l4_hash
&& !skb
->sw_hash
) {
1348 struct flow_keys keys
;
1349 __u32 hash
= __get_hash_from_flowi6(fl6
, &keys
);
1351 __skb_set_sw_hash(skb
, hash
, flow_keys_have_l4(&keys
));
1357 __u32
skb_get_hash_perturb(const struct sk_buff
*skb
,
1358 const siphash_key_t
*perturb
);
1360 static inline __u32
skb_get_hash_raw(const struct sk_buff
*skb
)
1365 static inline void skb_copy_hash(struct sk_buff
*to
, const struct sk_buff
*from
)
1367 to
->hash
= from
->hash
;
1368 to
->sw_hash
= from
->sw_hash
;
1369 to
->l4_hash
= from
->l4_hash
;
1372 static inline void skb_copy_decrypted(struct sk_buff
*to
,
1373 const struct sk_buff
*from
)
1375 #ifdef CONFIG_TLS_DEVICE
1376 to
->decrypted
= from
->decrypted
;
1380 #ifdef NET_SKBUFF_DATA_USES_OFFSET
1381 static inline unsigned char *skb_end_pointer(const struct sk_buff
*skb
)
1383 return skb
->head
+ skb
->end
;
1386 static inline unsigned int skb_end_offset(const struct sk_buff
*skb
)
1391 static inline unsigned char *skb_end_pointer(const struct sk_buff
*skb
)
1396 static inline unsigned int skb_end_offset(const struct sk_buff
*skb
)
1398 return skb
->end
- skb
->head
;
1403 #define skb_shinfo(SKB) ((struct skb_shared_info *)(skb_end_pointer(SKB)))
1405 static inline struct skb_shared_hwtstamps
*skb_hwtstamps(struct sk_buff
*skb
)
1407 return &skb_shinfo(skb
)->hwtstamps
;
1410 static inline struct ubuf_info
*skb_zcopy(struct sk_buff
*skb
)
1412 bool is_zcopy
= skb
&& skb_shinfo(skb
)->tx_flags
& SKBTX_DEV_ZEROCOPY
;
1414 return is_zcopy
? skb_uarg(skb
) : NULL
;
1417 static inline void skb_zcopy_set(struct sk_buff
*skb
, struct ubuf_info
*uarg
,
1420 if (skb
&& uarg
&& !skb_zcopy(skb
)) {
1421 if (unlikely(have_ref
&& *have_ref
))
1424 sock_zerocopy_get(uarg
);
1425 skb_shinfo(skb
)->destructor_arg
= uarg
;
1426 skb_shinfo(skb
)->tx_flags
|= SKBTX_ZEROCOPY_FRAG
;
1430 static inline void skb_zcopy_set_nouarg(struct sk_buff
*skb
, void *val
)
1432 skb_shinfo(skb
)->destructor_arg
= (void *)((uintptr_t) val
| 0x1UL
);
1433 skb_shinfo(skb
)->tx_flags
|= SKBTX_ZEROCOPY_FRAG
;
1436 static inline bool skb_zcopy_is_nouarg(struct sk_buff
*skb
)
1438 return (uintptr_t) skb_shinfo(skb
)->destructor_arg
& 0x1UL
;
1441 static inline void *skb_zcopy_get_nouarg(struct sk_buff
*skb
)
1443 return (void *)((uintptr_t) skb_shinfo(skb
)->destructor_arg
& ~0x1UL
);
1446 /* Release a reference on a zerocopy structure */
1447 static inline void skb_zcopy_clear(struct sk_buff
*skb
, bool zerocopy
)
1449 struct ubuf_info
*uarg
= skb_zcopy(skb
);
1452 if (skb_zcopy_is_nouarg(skb
)) {
1453 /* no notification callback */
1454 } else if (uarg
->callback
== sock_zerocopy_callback
) {
1455 uarg
->zerocopy
= uarg
->zerocopy
&& zerocopy
;
1456 sock_zerocopy_put(uarg
);
1458 uarg
->callback(uarg
, zerocopy
);
1461 skb_shinfo(skb
)->tx_flags
&= ~SKBTX_ZEROCOPY_FRAG
;
1465 /* Abort a zerocopy operation and revert zckey on error in send syscall */
1466 static inline void skb_zcopy_abort(struct sk_buff
*skb
)
1468 struct ubuf_info
*uarg
= skb_zcopy(skb
);
1471 sock_zerocopy_put_abort(uarg
, false);
1472 skb_shinfo(skb
)->tx_flags
&= ~SKBTX_ZEROCOPY_FRAG
;
1476 static inline void skb_mark_not_on_list(struct sk_buff
*skb
)
1481 /* Iterate through singly-linked GSO fragments of an skb. */
1482 #define skb_list_walk_safe(first, skb, next) \
1483 for ((skb) = (first), (next) = (skb) ? (skb)->next : NULL; (skb); \
1484 (skb) = (next), (next) = (skb) ? (skb)->next : NULL)
1486 static inline void skb_list_del_init(struct sk_buff
*skb
)
1488 __list_del_entry(&skb
->list
);
1489 skb_mark_not_on_list(skb
);
1493 * skb_queue_empty - check if a queue is empty
1496 * Returns true if the queue is empty, false otherwise.
1498 static inline int skb_queue_empty(const struct sk_buff_head
*list
)
1500 return list
->next
== (const struct sk_buff
*) list
;
1504 * skb_queue_empty_lockless - check if a queue is empty
1507 * Returns true if the queue is empty, false otherwise.
1508 * This variant can be used in lockless contexts.
1510 static inline bool skb_queue_empty_lockless(const struct sk_buff_head
*list
)
1512 return READ_ONCE(list
->next
) == (const struct sk_buff
*) list
;
1517 * skb_queue_is_last - check if skb is the last entry in the queue
1521 * Returns true if @skb is the last buffer on the list.
1523 static inline bool skb_queue_is_last(const struct sk_buff_head
*list
,
1524 const struct sk_buff
*skb
)
1526 return skb
->next
== (const struct sk_buff
*) list
;
1530 * skb_queue_is_first - check if skb is the first entry in the queue
1534 * Returns true if @skb is the first buffer on the list.
1536 static inline bool skb_queue_is_first(const struct sk_buff_head
*list
,
1537 const struct sk_buff
*skb
)
1539 return skb
->prev
== (const struct sk_buff
*) list
;
1543 * skb_queue_next - return the next packet in the queue
1545 * @skb: current buffer
1547 * Return the next packet in @list after @skb. It is only valid to
1548 * call this if skb_queue_is_last() evaluates to false.
1550 static inline struct sk_buff
*skb_queue_next(const struct sk_buff_head
*list
,
1551 const struct sk_buff
*skb
)
1553 /* This BUG_ON may seem severe, but if we just return then we
1554 * are going to dereference garbage.
1556 BUG_ON(skb_queue_is_last(list
, skb
));
1561 * skb_queue_prev - return the prev packet in the queue
1563 * @skb: current buffer
1565 * Return the prev packet in @list before @skb. It is only valid to
1566 * call this if skb_queue_is_first() evaluates to false.
1568 static inline struct sk_buff
*skb_queue_prev(const struct sk_buff_head
*list
,
1569 const struct sk_buff
*skb
)
1571 /* This BUG_ON may seem severe, but if we just return then we
1572 * are going to dereference garbage.
1574 BUG_ON(skb_queue_is_first(list
, skb
));
1579 * skb_get - reference buffer
1580 * @skb: buffer to reference
1582 * Makes another reference to a socket buffer and returns a pointer
1585 static inline struct sk_buff
*skb_get(struct sk_buff
*skb
)
1587 refcount_inc(&skb
->users
);
1592 * If users == 1, we are the only owner and can avoid redundant atomic changes.
1596 * skb_cloned - is the buffer a clone
1597 * @skb: buffer to check
1599 * Returns true if the buffer was generated with skb_clone() and is
1600 * one of multiple shared copies of the buffer. Cloned buffers are
1601 * shared data so must not be written to under normal circumstances.
1603 static inline int skb_cloned(const struct sk_buff
*skb
)
1605 return skb
->cloned
&&
1606 (atomic_read(&skb_shinfo(skb
)->dataref
) & SKB_DATAREF_MASK
) != 1;
1609 static inline int skb_unclone(struct sk_buff
*skb
, gfp_t pri
)
1611 might_sleep_if(gfpflags_allow_blocking(pri
));
1613 if (skb_cloned(skb
))
1614 return pskb_expand_head(skb
, 0, 0, pri
);
1620 * skb_header_cloned - is the header a clone
1621 * @skb: buffer to check
1623 * Returns true if modifying the header part of the buffer requires
1624 * the data to be copied.
1626 static inline int skb_header_cloned(const struct sk_buff
*skb
)
1633 dataref
= atomic_read(&skb_shinfo(skb
)->dataref
);
1634 dataref
= (dataref
& SKB_DATAREF_MASK
) - (dataref
>> SKB_DATAREF_SHIFT
);
1635 return dataref
!= 1;
1638 static inline int skb_header_unclone(struct sk_buff
*skb
, gfp_t pri
)
1640 might_sleep_if(gfpflags_allow_blocking(pri
));
1642 if (skb_header_cloned(skb
))
1643 return pskb_expand_head(skb
, 0, 0, pri
);
1649 * __skb_header_release - release reference to header
1650 * @skb: buffer to operate on
1652 static inline void __skb_header_release(struct sk_buff
*skb
)
1655 atomic_set(&skb_shinfo(skb
)->dataref
, 1 + (1 << SKB_DATAREF_SHIFT
));
1660 * skb_shared - is the buffer shared
1661 * @skb: buffer to check
1663 * Returns true if more than one person has a reference to this
1666 static inline int skb_shared(const struct sk_buff
*skb
)
1668 return refcount_read(&skb
->users
) != 1;
1672 * skb_share_check - check if buffer is shared and if so clone it
1673 * @skb: buffer to check
1674 * @pri: priority for memory allocation
1676 * If the buffer is shared the buffer is cloned and the old copy
1677 * drops a reference. A new clone with a single reference is returned.
1678 * If the buffer is not shared the original buffer is returned. When
1679 * being called from interrupt status or with spinlocks held pri must
1682 * NULL is returned on a memory allocation failure.
1684 static inline struct sk_buff
*skb_share_check(struct sk_buff
*skb
, gfp_t pri
)
1686 might_sleep_if(gfpflags_allow_blocking(pri
));
1687 if (skb_shared(skb
)) {
1688 struct sk_buff
*nskb
= skb_clone(skb
, pri
);
1700 * Copy shared buffers into a new sk_buff. We effectively do COW on
1701 * packets to handle cases where we have a local reader and forward
1702 * and a couple of other messy ones. The normal one is tcpdumping
1703 * a packet thats being forwarded.
1707 * skb_unshare - make a copy of a shared buffer
1708 * @skb: buffer to check
1709 * @pri: priority for memory allocation
1711 * If the socket buffer is a clone then this function creates a new
1712 * copy of the data, drops a reference count on the old copy and returns
1713 * the new copy with the reference count at 1. If the buffer is not a clone
1714 * the original buffer is returned. When called with a spinlock held or
1715 * from interrupt state @pri must be %GFP_ATOMIC
1717 * %NULL is returned on a memory allocation failure.
1719 static inline struct sk_buff
*skb_unshare(struct sk_buff
*skb
,
1722 might_sleep_if(gfpflags_allow_blocking(pri
));
1723 if (skb_cloned(skb
)) {
1724 struct sk_buff
*nskb
= skb_copy(skb
, pri
);
1726 /* Free our shared copy */
1737 * skb_peek - peek at the head of an &sk_buff_head
1738 * @list_: list to peek at
1740 * Peek an &sk_buff. Unlike most other operations you _MUST_
1741 * be careful with this one. A peek leaves the buffer on the
1742 * list and someone else may run off with it. You must hold
1743 * the appropriate locks or have a private queue to do this.
1745 * Returns %NULL for an empty list or a pointer to the head element.
1746 * The reference count is not incremented and the reference is therefore
1747 * volatile. Use with caution.
1749 static inline struct sk_buff
*skb_peek(const struct sk_buff_head
*list_
)
1751 struct sk_buff
*skb
= list_
->next
;
1753 if (skb
== (struct sk_buff
*)list_
)
1759 * __skb_peek - peek at the head of a non-empty &sk_buff_head
1760 * @list_: list to peek at
1762 * Like skb_peek(), but the caller knows that the list is not empty.
1764 static inline struct sk_buff
*__skb_peek(const struct sk_buff_head
*list_
)
1770 * skb_peek_next - peek skb following the given one from a queue
1771 * @skb: skb to start from
1772 * @list_: list to peek at
1774 * Returns %NULL when the end of the list is met or a pointer to the
1775 * next element. The reference count is not incremented and the
1776 * reference is therefore volatile. Use with caution.
1778 static inline struct sk_buff
*skb_peek_next(struct sk_buff
*skb
,
1779 const struct sk_buff_head
*list_
)
1781 struct sk_buff
*next
= skb
->next
;
1783 if (next
== (struct sk_buff
*)list_
)
1789 * skb_peek_tail - peek at the tail of an &sk_buff_head
1790 * @list_: list to peek at
1792 * Peek an &sk_buff. Unlike most other operations you _MUST_
1793 * be careful with this one. A peek leaves the buffer on the
1794 * list and someone else may run off with it. You must hold
1795 * the appropriate locks or have a private queue to do this.
1797 * Returns %NULL for an empty list or a pointer to the tail element.
1798 * The reference count is not incremented and the reference is therefore
1799 * volatile. Use with caution.
1801 static inline struct sk_buff
*skb_peek_tail(const struct sk_buff_head
*list_
)
1803 struct sk_buff
*skb
= READ_ONCE(list_
->prev
);
1805 if (skb
== (struct sk_buff
*)list_
)
1812 * skb_queue_len - get queue length
1813 * @list_: list to measure
1815 * Return the length of an &sk_buff queue.
1817 static inline __u32
skb_queue_len(const struct sk_buff_head
*list_
)
1823 * __skb_queue_head_init - initialize non-spinlock portions of sk_buff_head
1824 * @list: queue to initialize
1826 * This initializes only the list and queue length aspects of
1827 * an sk_buff_head object. This allows to initialize the list
1828 * aspects of an sk_buff_head without reinitializing things like
1829 * the spinlock. It can also be used for on-stack sk_buff_head
1830 * objects where the spinlock is known to not be used.
1832 static inline void __skb_queue_head_init(struct sk_buff_head
*list
)
1834 list
->prev
= list
->next
= (struct sk_buff
*)list
;
1839 * This function creates a split out lock class for each invocation;
1840 * this is needed for now since a whole lot of users of the skb-queue
1841 * infrastructure in drivers have different locking usage (in hardirq)
1842 * than the networking core (in softirq only). In the long run either the
1843 * network layer or drivers should need annotation to consolidate the
1844 * main types of usage into 3 classes.
1846 static inline void skb_queue_head_init(struct sk_buff_head
*list
)
1848 spin_lock_init(&list
->lock
);
1849 __skb_queue_head_init(list
);
1852 static inline void skb_queue_head_init_class(struct sk_buff_head
*list
,
1853 struct lock_class_key
*class)
1855 skb_queue_head_init(list
);
1856 lockdep_set_class(&list
->lock
, class);
1860 * Insert an sk_buff on a list.
1862 * The "__skb_xxxx()" functions are the non-atomic ones that
1863 * can only be called with interrupts disabled.
1865 static inline void __skb_insert(struct sk_buff
*newsk
,
1866 struct sk_buff
*prev
, struct sk_buff
*next
,
1867 struct sk_buff_head
*list
)
1869 /* See skb_queue_empty_lockless() and skb_peek_tail()
1870 * for the opposite READ_ONCE()
1872 WRITE_ONCE(newsk
->next
, next
);
1873 WRITE_ONCE(newsk
->prev
, prev
);
1874 WRITE_ONCE(next
->prev
, newsk
);
1875 WRITE_ONCE(prev
->next
, newsk
);
1879 static inline void __skb_queue_splice(const struct sk_buff_head
*list
,
1880 struct sk_buff
*prev
,
1881 struct sk_buff
*next
)
1883 struct sk_buff
*first
= list
->next
;
1884 struct sk_buff
*last
= list
->prev
;
1886 WRITE_ONCE(first
->prev
, prev
);
1887 WRITE_ONCE(prev
->next
, first
);
1889 WRITE_ONCE(last
->next
, next
);
1890 WRITE_ONCE(next
->prev
, last
);
1894 * skb_queue_splice - join two skb lists, this is designed for stacks
1895 * @list: the new list to add
1896 * @head: the place to add it in the first list
1898 static inline void skb_queue_splice(const struct sk_buff_head
*list
,
1899 struct sk_buff_head
*head
)
1901 if (!skb_queue_empty(list
)) {
1902 __skb_queue_splice(list
, (struct sk_buff
*) head
, head
->next
);
1903 head
->qlen
+= list
->qlen
;
1908 * skb_queue_splice_init - join two skb lists and reinitialise the emptied list
1909 * @list: the new list to add
1910 * @head: the place to add it in the first list
1912 * The list at @list is reinitialised
1914 static inline void skb_queue_splice_init(struct sk_buff_head
*list
,
1915 struct sk_buff_head
*head
)
1917 if (!skb_queue_empty(list
)) {
1918 __skb_queue_splice(list
, (struct sk_buff
*) head
, head
->next
);
1919 head
->qlen
+= list
->qlen
;
1920 __skb_queue_head_init(list
);
1925 * skb_queue_splice_tail - join two skb lists, each list being a queue
1926 * @list: the new list to add
1927 * @head: the place to add it in the first list
1929 static inline void skb_queue_splice_tail(const struct sk_buff_head
*list
,
1930 struct sk_buff_head
*head
)
1932 if (!skb_queue_empty(list
)) {
1933 __skb_queue_splice(list
, head
->prev
, (struct sk_buff
*) head
);
1934 head
->qlen
+= list
->qlen
;
1939 * skb_queue_splice_tail_init - join two skb lists and reinitialise the emptied list
1940 * @list: the new list to add
1941 * @head: the place to add it in the first list
1943 * Each of the lists is a queue.
1944 * The list at @list is reinitialised
1946 static inline void skb_queue_splice_tail_init(struct sk_buff_head
*list
,
1947 struct sk_buff_head
*head
)
1949 if (!skb_queue_empty(list
)) {
1950 __skb_queue_splice(list
, head
->prev
, (struct sk_buff
*) head
);
1951 head
->qlen
+= list
->qlen
;
1952 __skb_queue_head_init(list
);
1957 * __skb_queue_after - queue a buffer at the list head
1958 * @list: list to use
1959 * @prev: place after this buffer
1960 * @newsk: buffer to queue
1962 * Queue a buffer int the middle of a list. This function takes no locks
1963 * and you must therefore hold required locks before calling it.
1965 * A buffer cannot be placed on two lists at the same time.
1967 static inline void __skb_queue_after(struct sk_buff_head
*list
,
1968 struct sk_buff
*prev
,
1969 struct sk_buff
*newsk
)
1971 __skb_insert(newsk
, prev
, prev
->next
, list
);
1974 void skb_append(struct sk_buff
*old
, struct sk_buff
*newsk
,
1975 struct sk_buff_head
*list
);
1977 static inline void __skb_queue_before(struct sk_buff_head
*list
,
1978 struct sk_buff
*next
,
1979 struct sk_buff
*newsk
)
1981 __skb_insert(newsk
, next
->prev
, next
, list
);
1985 * __skb_queue_head - queue a buffer at the list head
1986 * @list: list to use
1987 * @newsk: buffer to queue
1989 * Queue a buffer at the start of a list. This function takes no locks
1990 * and you must therefore hold required locks before calling it.
1992 * A buffer cannot be placed on two lists at the same time.
1994 static inline void __skb_queue_head(struct sk_buff_head
*list
,
1995 struct sk_buff
*newsk
)
1997 __skb_queue_after(list
, (struct sk_buff
*)list
, newsk
);
1999 void skb_queue_head(struct sk_buff_head
*list
, struct sk_buff
*newsk
);
2002 * __skb_queue_tail - queue a buffer at the list tail
2003 * @list: list to use
2004 * @newsk: buffer to queue
2006 * Queue a buffer at the end of a list. This function takes no locks
2007 * and you must therefore hold required locks before calling it.
2009 * A buffer cannot be placed on two lists at the same time.
2011 static inline void __skb_queue_tail(struct sk_buff_head
*list
,
2012 struct sk_buff
*newsk
)
2014 __skb_queue_before(list
, (struct sk_buff
*)list
, newsk
);
2016 void skb_queue_tail(struct sk_buff_head
*list
, struct sk_buff
*newsk
);
2019 * remove sk_buff from list. _Must_ be called atomically, and with
2022 void skb_unlink(struct sk_buff
*skb
, struct sk_buff_head
*list
);
2023 static inline void __skb_unlink(struct sk_buff
*skb
, struct sk_buff_head
*list
)
2025 struct sk_buff
*next
, *prev
;
2030 skb
->next
= skb
->prev
= NULL
;
2031 WRITE_ONCE(next
->prev
, prev
);
2032 WRITE_ONCE(prev
->next
, next
);
2036 * __skb_dequeue - remove from the head of the queue
2037 * @list: list to dequeue from
2039 * Remove the head of the list. This function does not take any locks
2040 * so must be used with appropriate locks held only. The head item is
2041 * returned or %NULL if the list is empty.
2043 static inline struct sk_buff
*__skb_dequeue(struct sk_buff_head
*list
)
2045 struct sk_buff
*skb
= skb_peek(list
);
2047 __skb_unlink(skb
, list
);
2050 struct sk_buff
*skb_dequeue(struct sk_buff_head
*list
);
2053 * __skb_dequeue_tail - remove from the tail of the queue
2054 * @list: list to dequeue from
2056 * Remove the tail of the list. This function does not take any locks
2057 * so must be used with appropriate locks held only. The tail item is
2058 * returned or %NULL if the list is empty.
2060 static inline struct sk_buff
*__skb_dequeue_tail(struct sk_buff_head
*list
)
2062 struct sk_buff
*skb
= skb_peek_tail(list
);
2064 __skb_unlink(skb
, list
);
2067 struct sk_buff
*skb_dequeue_tail(struct sk_buff_head
*list
);
2070 static inline bool skb_is_nonlinear(const struct sk_buff
*skb
)
2072 return skb
->data_len
;
2075 static inline unsigned int skb_headlen(const struct sk_buff
*skb
)
2077 return skb
->len
- skb
->data_len
;
2080 static inline unsigned int __skb_pagelen(const struct sk_buff
*skb
)
2082 unsigned int i
, len
= 0;
2084 for (i
= skb_shinfo(skb
)->nr_frags
- 1; (int)i
>= 0; i
--)
2085 len
+= skb_frag_size(&skb_shinfo(skb
)->frags
[i
]);
2089 static inline unsigned int skb_pagelen(const struct sk_buff
*skb
)
2091 return skb_headlen(skb
) + __skb_pagelen(skb
);
2095 * __skb_fill_page_desc - initialise a paged fragment in an skb
2096 * @skb: buffer containing fragment to be initialised
2097 * @i: paged fragment index to initialise
2098 * @page: the page to use for this fragment
2099 * @off: the offset to the data with @page
2100 * @size: the length of the data
2102 * Initialises the @i'th fragment of @skb to point to &size bytes at
2103 * offset @off within @page.
2105 * Does not take any additional reference on the fragment.
2107 static inline void __skb_fill_page_desc(struct sk_buff
*skb
, int i
,
2108 struct page
*page
, int off
, int size
)
2110 skb_frag_t
*frag
= &skb_shinfo(skb
)->frags
[i
];
2113 * Propagate page pfmemalloc to the skb if we can. The problem is
2114 * that not all callers have unique ownership of the page but rely
2115 * on page_is_pfmemalloc doing the right thing(tm).
2117 frag
->bv_page
= page
;
2118 frag
->bv_offset
= off
;
2119 skb_frag_size_set(frag
, size
);
2121 page
= compound_head(page
);
2122 if (page_is_pfmemalloc(page
))
2123 skb
->pfmemalloc
= true;
2127 * skb_fill_page_desc - initialise a paged fragment in an skb
2128 * @skb: buffer containing fragment to be initialised
2129 * @i: paged fragment index to initialise
2130 * @page: the page to use for this fragment
2131 * @off: the offset to the data with @page
2132 * @size: the length of the data
2134 * As per __skb_fill_page_desc() -- initialises the @i'th fragment of
2135 * @skb to point to @size bytes at offset @off within @page. In
2136 * addition updates @skb such that @i is the last fragment.
2138 * Does not take any additional reference on the fragment.
2140 static inline void skb_fill_page_desc(struct sk_buff
*skb
, int i
,
2141 struct page
*page
, int off
, int size
)
2143 __skb_fill_page_desc(skb
, i
, page
, off
, size
);
2144 skb_shinfo(skb
)->nr_frags
= i
+ 1;
2147 void skb_add_rx_frag(struct sk_buff
*skb
, int i
, struct page
*page
, int off
,
2148 int size
, unsigned int truesize
);
2150 void skb_coalesce_rx_frag(struct sk_buff
*skb
, int i
, int size
,
2151 unsigned int truesize
);
2153 #define SKB_LINEAR_ASSERT(skb) BUG_ON(skb_is_nonlinear(skb))
2155 #ifdef NET_SKBUFF_DATA_USES_OFFSET
2156 static inline unsigned char *skb_tail_pointer(const struct sk_buff
*skb
)
2158 return skb
->head
+ skb
->tail
;
2161 static inline void skb_reset_tail_pointer(struct sk_buff
*skb
)
2163 skb
->tail
= skb
->data
- skb
->head
;
2166 static inline void skb_set_tail_pointer(struct sk_buff
*skb
, const int offset
)
2168 skb_reset_tail_pointer(skb
);
2169 skb
->tail
+= offset
;
2172 #else /* NET_SKBUFF_DATA_USES_OFFSET */
2173 static inline unsigned char *skb_tail_pointer(const struct sk_buff
*skb
)
2178 static inline void skb_reset_tail_pointer(struct sk_buff
*skb
)
2180 skb
->tail
= skb
->data
;
2183 static inline void skb_set_tail_pointer(struct sk_buff
*skb
, const int offset
)
2185 skb
->tail
= skb
->data
+ offset
;
2188 #endif /* NET_SKBUFF_DATA_USES_OFFSET */
2191 * Add data to an sk_buff
2193 void *pskb_put(struct sk_buff
*skb
, struct sk_buff
*tail
, int len
);
2194 void *skb_put(struct sk_buff
*skb
, unsigned int len
);
2195 static inline void *__skb_put(struct sk_buff
*skb
, unsigned int len
)
2197 void *tmp
= skb_tail_pointer(skb
);
2198 SKB_LINEAR_ASSERT(skb
);
2204 static inline void *__skb_put_zero(struct sk_buff
*skb
, unsigned int len
)
2206 void *tmp
= __skb_put(skb
, len
);
2208 memset(tmp
, 0, len
);
2212 static inline void *__skb_put_data(struct sk_buff
*skb
, const void *data
,
2215 void *tmp
= __skb_put(skb
, len
);
2217 memcpy(tmp
, data
, len
);
2221 static inline void __skb_put_u8(struct sk_buff
*skb
, u8 val
)
2223 *(u8
*)__skb_put(skb
, 1) = val
;
2226 static inline void *skb_put_zero(struct sk_buff
*skb
, unsigned int len
)
2228 void *tmp
= skb_put(skb
, len
);
2230 memset(tmp
, 0, len
);
2235 static inline void *skb_put_data(struct sk_buff
*skb
, const void *data
,
2238 void *tmp
= skb_put(skb
, len
);
2240 memcpy(tmp
, data
, len
);
2245 static inline void skb_put_u8(struct sk_buff
*skb
, u8 val
)
2247 *(u8
*)skb_put(skb
, 1) = val
;
2250 void *skb_push(struct sk_buff
*skb
, unsigned int len
);
2251 static inline void *__skb_push(struct sk_buff
*skb
, unsigned int len
)
2258 void *skb_pull(struct sk_buff
*skb
, unsigned int len
);
2259 static inline void *__skb_pull(struct sk_buff
*skb
, unsigned int len
)
2262 BUG_ON(skb
->len
< skb
->data_len
);
2263 return skb
->data
+= len
;
2266 static inline void *skb_pull_inline(struct sk_buff
*skb
, unsigned int len
)
2268 return unlikely(len
> skb
->len
) ? NULL
: __skb_pull(skb
, len
);
2271 void *__pskb_pull_tail(struct sk_buff
*skb
, int delta
);
2273 static inline void *__pskb_pull(struct sk_buff
*skb
, unsigned int len
)
2275 if (len
> skb_headlen(skb
) &&
2276 !__pskb_pull_tail(skb
, len
- skb_headlen(skb
)))
2279 return skb
->data
+= len
;
2282 static inline void *pskb_pull(struct sk_buff
*skb
, unsigned int len
)
2284 return unlikely(len
> skb
->len
) ? NULL
: __pskb_pull(skb
, len
);
2287 static inline bool pskb_may_pull(struct sk_buff
*skb
, unsigned int len
)
2289 if (likely(len
<= skb_headlen(skb
)))
2291 if (unlikely(len
> skb
->len
))
2293 return __pskb_pull_tail(skb
, len
- skb_headlen(skb
)) != NULL
;
2296 void skb_condense(struct sk_buff
*skb
);
2299 * skb_headroom - bytes at buffer head
2300 * @skb: buffer to check
2302 * Return the number of bytes of free space at the head of an &sk_buff.
2304 static inline unsigned int skb_headroom(const struct sk_buff
*skb
)
2306 return skb
->data
- skb
->head
;
2310 * skb_tailroom - bytes at buffer end
2311 * @skb: buffer to check
2313 * Return the number of bytes of free space at the tail of an sk_buff
2315 static inline int skb_tailroom(const struct sk_buff
*skb
)
2317 return skb_is_nonlinear(skb
) ? 0 : skb
->end
- skb
->tail
;
2321 * skb_availroom - bytes at buffer end
2322 * @skb: buffer to check
2324 * Return the number of bytes of free space at the tail of an sk_buff
2325 * allocated by sk_stream_alloc()
2327 static inline int skb_availroom(const struct sk_buff
*skb
)
2329 if (skb_is_nonlinear(skb
))
2332 return skb
->end
- skb
->tail
- skb
->reserved_tailroom
;
2336 * skb_reserve - adjust headroom
2337 * @skb: buffer to alter
2338 * @len: bytes to move
2340 * Increase the headroom of an empty &sk_buff by reducing the tail
2341 * room. This is only allowed for an empty buffer.
2343 static inline void skb_reserve(struct sk_buff
*skb
, int len
)
2350 * skb_tailroom_reserve - adjust reserved_tailroom
2351 * @skb: buffer to alter
2352 * @mtu: maximum amount of headlen permitted
2353 * @needed_tailroom: minimum amount of reserved_tailroom
2355 * Set reserved_tailroom so that headlen can be as large as possible but
2356 * not larger than mtu and tailroom cannot be smaller than
2358 * The required headroom should already have been reserved before using
2361 static inline void skb_tailroom_reserve(struct sk_buff
*skb
, unsigned int mtu
,
2362 unsigned int needed_tailroom
)
2364 SKB_LINEAR_ASSERT(skb
);
2365 if (mtu
< skb_tailroom(skb
) - needed_tailroom
)
2366 /* use at most mtu */
2367 skb
->reserved_tailroom
= skb_tailroom(skb
) - mtu
;
2369 /* use up to all available space */
2370 skb
->reserved_tailroom
= needed_tailroom
;
2373 #define ENCAP_TYPE_ETHER 0
2374 #define ENCAP_TYPE_IPPROTO 1
2376 static inline void skb_set_inner_protocol(struct sk_buff
*skb
,
2379 skb
->inner_protocol
= protocol
;
2380 skb
->inner_protocol_type
= ENCAP_TYPE_ETHER
;
2383 static inline void skb_set_inner_ipproto(struct sk_buff
*skb
,
2386 skb
->inner_ipproto
= ipproto
;
2387 skb
->inner_protocol_type
= ENCAP_TYPE_IPPROTO
;
2390 static inline void skb_reset_inner_headers(struct sk_buff
*skb
)
2392 skb
->inner_mac_header
= skb
->mac_header
;
2393 skb
->inner_network_header
= skb
->network_header
;
2394 skb
->inner_transport_header
= skb
->transport_header
;
2397 static inline void skb_reset_mac_len(struct sk_buff
*skb
)
2399 skb
->mac_len
= skb
->network_header
- skb
->mac_header
;
2402 static inline unsigned char *skb_inner_transport_header(const struct sk_buff
2405 return skb
->head
+ skb
->inner_transport_header
;
2408 static inline int skb_inner_transport_offset(const struct sk_buff
*skb
)
2410 return skb_inner_transport_header(skb
) - skb
->data
;
2413 static inline void skb_reset_inner_transport_header(struct sk_buff
*skb
)
2415 skb
->inner_transport_header
= skb
->data
- skb
->head
;
2418 static inline void skb_set_inner_transport_header(struct sk_buff
*skb
,
2421 skb_reset_inner_transport_header(skb
);
2422 skb
->inner_transport_header
+= offset
;
2425 static inline unsigned char *skb_inner_network_header(const struct sk_buff
*skb
)
2427 return skb
->head
+ skb
->inner_network_header
;
2430 static inline void skb_reset_inner_network_header(struct sk_buff
*skb
)
2432 skb
->inner_network_header
= skb
->data
- skb
->head
;
2435 static inline void skb_set_inner_network_header(struct sk_buff
*skb
,
2438 skb_reset_inner_network_header(skb
);
2439 skb
->inner_network_header
+= offset
;
2442 static inline unsigned char *skb_inner_mac_header(const struct sk_buff
*skb
)
2444 return skb
->head
+ skb
->inner_mac_header
;
2447 static inline void skb_reset_inner_mac_header(struct sk_buff
*skb
)
2449 skb
->inner_mac_header
= skb
->data
- skb
->head
;
2452 static inline void skb_set_inner_mac_header(struct sk_buff
*skb
,
2455 skb_reset_inner_mac_header(skb
);
2456 skb
->inner_mac_header
+= offset
;
2458 static inline bool skb_transport_header_was_set(const struct sk_buff
*skb
)
2460 return skb
->transport_header
!= (typeof(skb
->transport_header
))~0U;
2463 static inline unsigned char *skb_transport_header(const struct sk_buff
*skb
)
2465 return skb
->head
+ skb
->transport_header
;
2468 static inline void skb_reset_transport_header(struct sk_buff
*skb
)
2470 skb
->transport_header
= skb
->data
- skb
->head
;
2473 static inline void skb_set_transport_header(struct sk_buff
*skb
,
2476 skb_reset_transport_header(skb
);
2477 skb
->transport_header
+= offset
;
2480 static inline unsigned char *skb_network_header(const struct sk_buff
*skb
)
2482 return skb
->head
+ skb
->network_header
;
2485 static inline void skb_reset_network_header(struct sk_buff
*skb
)
2487 skb
->network_header
= skb
->data
- skb
->head
;
2490 static inline void skb_set_network_header(struct sk_buff
*skb
, const int offset
)
2492 skb_reset_network_header(skb
);
2493 skb
->network_header
+= offset
;
2496 static inline unsigned char *skb_mac_header(const struct sk_buff
*skb
)
2498 return skb
->head
+ skb
->mac_header
;
2501 static inline int skb_mac_offset(const struct sk_buff
*skb
)
2503 return skb_mac_header(skb
) - skb
->data
;
2506 static inline u32
skb_mac_header_len(const struct sk_buff
*skb
)
2508 return skb
->network_header
- skb
->mac_header
;
2511 static inline int skb_mac_header_was_set(const struct sk_buff
*skb
)
2513 return skb
->mac_header
!= (typeof(skb
->mac_header
))~0U;
2516 static inline void skb_reset_mac_header(struct sk_buff
*skb
)
2518 skb
->mac_header
= skb
->data
- skb
->head
;
2521 static inline void skb_set_mac_header(struct sk_buff
*skb
, const int offset
)
2523 skb_reset_mac_header(skb
);
2524 skb
->mac_header
+= offset
;
2527 static inline void skb_pop_mac_header(struct sk_buff
*skb
)
2529 skb
->mac_header
= skb
->network_header
;
2532 static inline void skb_probe_transport_header(struct sk_buff
*skb
)
2534 struct flow_keys_basic keys
;
2536 if (skb_transport_header_was_set(skb
))
2539 if (skb_flow_dissect_flow_keys_basic(NULL
, skb
, &keys
,
2541 skb_set_transport_header(skb
, keys
.control
.thoff
);
2544 static inline void skb_mac_header_rebuild(struct sk_buff
*skb
)
2546 if (skb_mac_header_was_set(skb
)) {
2547 const unsigned char *old_mac
= skb_mac_header(skb
);
2549 skb_set_mac_header(skb
, -skb
->mac_len
);
2550 memmove(skb_mac_header(skb
), old_mac
, skb
->mac_len
);
2554 static inline int skb_checksum_start_offset(const struct sk_buff
*skb
)
2556 return skb
->csum_start
- skb_headroom(skb
);
2559 static inline unsigned char *skb_checksum_start(const struct sk_buff
*skb
)
2561 return skb
->head
+ skb
->csum_start
;
2564 static inline int skb_transport_offset(const struct sk_buff
*skb
)
2566 return skb_transport_header(skb
) - skb
->data
;
2569 static inline u32
skb_network_header_len(const struct sk_buff
*skb
)
2571 return skb
->transport_header
- skb
->network_header
;
2574 static inline u32
skb_inner_network_header_len(const struct sk_buff
*skb
)
2576 return skb
->inner_transport_header
- skb
->inner_network_header
;
2579 static inline int skb_network_offset(const struct sk_buff
*skb
)
2581 return skb_network_header(skb
) - skb
->data
;
2584 static inline int skb_inner_network_offset(const struct sk_buff
*skb
)
2586 return skb_inner_network_header(skb
) - skb
->data
;
2589 static inline int pskb_network_may_pull(struct sk_buff
*skb
, unsigned int len
)
2591 return pskb_may_pull(skb
, skb_network_offset(skb
) + len
);
2595 * CPUs often take a performance hit when accessing unaligned memory
2596 * locations. The actual performance hit varies, it can be small if the
2597 * hardware handles it or large if we have to take an exception and fix it
2600 * Since an ethernet header is 14 bytes network drivers often end up with
2601 * the IP header at an unaligned offset. The IP header can be aligned by
2602 * shifting the start of the packet by 2 bytes. Drivers should do this
2605 * skb_reserve(skb, NET_IP_ALIGN);
2607 * The downside to this alignment of the IP header is that the DMA is now
2608 * unaligned. On some architectures the cost of an unaligned DMA is high
2609 * and this cost outweighs the gains made by aligning the IP header.
2611 * Since this trade off varies between architectures, we allow NET_IP_ALIGN
2614 #ifndef NET_IP_ALIGN
2615 #define NET_IP_ALIGN 2
2619 * The networking layer reserves some headroom in skb data (via
2620 * dev_alloc_skb). This is used to avoid having to reallocate skb data when
2621 * the header has to grow. In the default case, if the header has to grow
2622 * 32 bytes or less we avoid the reallocation.
2624 * Unfortunately this headroom changes the DMA alignment of the resulting
2625 * network packet. As for NET_IP_ALIGN, this unaligned DMA is expensive
2626 * on some architectures. An architecture can override this value,
2627 * perhaps setting it to a cacheline in size (since that will maintain
2628 * cacheline alignment of the DMA). It must be a power of 2.
2630 * Various parts of the networking layer expect at least 32 bytes of
2631 * headroom, you should not reduce this.
2633 * Using max(32, L1_CACHE_BYTES) makes sense (especially with RPS)
2634 * to reduce average number of cache lines per packet.
2635 * get_rps_cpus() for example only access one 64 bytes aligned block :
2636 * NET_IP_ALIGN(2) + ethernet_header(14) + IP_header(20/40) + ports(8)
2639 #define NET_SKB_PAD max(32, L1_CACHE_BYTES)
2642 int ___pskb_trim(struct sk_buff
*skb
, unsigned int len
);
2644 static inline void __skb_set_length(struct sk_buff
*skb
, unsigned int len
)
2646 if (WARN_ON(skb_is_nonlinear(skb
)))
2649 skb_set_tail_pointer(skb
, len
);
2652 static inline void __skb_trim(struct sk_buff
*skb
, unsigned int len
)
2654 __skb_set_length(skb
, len
);
2657 void skb_trim(struct sk_buff
*skb
, unsigned int len
);
2659 static inline int __pskb_trim(struct sk_buff
*skb
, unsigned int len
)
2662 return ___pskb_trim(skb
, len
);
2663 __skb_trim(skb
, len
);
2667 static inline int pskb_trim(struct sk_buff
*skb
, unsigned int len
)
2669 return (len
< skb
->len
) ? __pskb_trim(skb
, len
) : 0;
2673 * pskb_trim_unique - remove end from a paged unique (not cloned) buffer
2674 * @skb: buffer to alter
2677 * This is identical to pskb_trim except that the caller knows that
2678 * the skb is not cloned so we should never get an error due to out-
2681 static inline void pskb_trim_unique(struct sk_buff
*skb
, unsigned int len
)
2683 int err
= pskb_trim(skb
, len
);
2687 static inline int __skb_grow(struct sk_buff
*skb
, unsigned int len
)
2689 unsigned int diff
= len
- skb
->len
;
2691 if (skb_tailroom(skb
) < diff
) {
2692 int ret
= pskb_expand_head(skb
, 0, diff
- skb_tailroom(skb
),
2697 __skb_set_length(skb
, len
);
2702 * skb_orphan - orphan a buffer
2703 * @skb: buffer to orphan
2705 * If a buffer currently has an owner then we call the owner's
2706 * destructor function and make the @skb unowned. The buffer continues
2707 * to exist but is no longer charged to its former owner.
2709 static inline void skb_orphan(struct sk_buff
*skb
)
2711 if (skb
->destructor
) {
2712 skb
->destructor(skb
);
2713 skb
->destructor
= NULL
;
2721 * skb_orphan_frags - orphan the frags contained in a buffer
2722 * @skb: buffer to orphan frags from
2723 * @gfp_mask: allocation mask for replacement pages
2725 * For each frag in the SKB which needs a destructor (i.e. has an
2726 * owner) create a copy of that frag and release the original
2727 * page by calling the destructor.
2729 static inline int skb_orphan_frags(struct sk_buff
*skb
, gfp_t gfp_mask
)
2731 if (likely(!skb_zcopy(skb
)))
2733 if (!skb_zcopy_is_nouarg(skb
) &&
2734 skb_uarg(skb
)->callback
== sock_zerocopy_callback
)
2736 return skb_copy_ubufs(skb
, gfp_mask
);
2739 /* Frags must be orphaned, even if refcounted, if skb might loop to rx path */
2740 static inline int skb_orphan_frags_rx(struct sk_buff
*skb
, gfp_t gfp_mask
)
2742 if (likely(!skb_zcopy(skb
)))
2744 return skb_copy_ubufs(skb
, gfp_mask
);
2748 * __skb_queue_purge - empty a list
2749 * @list: list to empty
2751 * Delete all buffers on an &sk_buff list. Each buffer is removed from
2752 * the list and one reference dropped. This function does not take the
2753 * list lock and the caller must hold the relevant locks to use it.
2755 static inline void __skb_queue_purge(struct sk_buff_head
*list
)
2757 struct sk_buff
*skb
;
2758 while ((skb
= __skb_dequeue(list
)) != NULL
)
2761 void skb_queue_purge(struct sk_buff_head
*list
);
2763 unsigned int skb_rbtree_purge(struct rb_root
*root
);
2765 void *netdev_alloc_frag(unsigned int fragsz
);
2767 struct sk_buff
*__netdev_alloc_skb(struct net_device
*dev
, unsigned int length
,
2771 * netdev_alloc_skb - allocate an skbuff for rx on a specific device
2772 * @dev: network device to receive on
2773 * @length: length to allocate
2775 * Allocate a new &sk_buff and assign it a usage count of one. The
2776 * buffer has unspecified headroom built in. Users should allocate
2777 * the headroom they think they need without accounting for the
2778 * built in space. The built in space is used for optimisations.
2780 * %NULL is returned if there is no free memory. Although this function
2781 * allocates memory it can be called from an interrupt.
2783 static inline struct sk_buff
*netdev_alloc_skb(struct net_device
*dev
,
2784 unsigned int length
)
2786 return __netdev_alloc_skb(dev
, length
, GFP_ATOMIC
);
2789 /* legacy helper around __netdev_alloc_skb() */
2790 static inline struct sk_buff
*__dev_alloc_skb(unsigned int length
,
2793 return __netdev_alloc_skb(NULL
, length
, gfp_mask
);
2796 /* legacy helper around netdev_alloc_skb() */
2797 static inline struct sk_buff
*dev_alloc_skb(unsigned int length
)
2799 return netdev_alloc_skb(NULL
, length
);
2803 static inline struct sk_buff
*__netdev_alloc_skb_ip_align(struct net_device
*dev
,
2804 unsigned int length
, gfp_t gfp
)
2806 struct sk_buff
*skb
= __netdev_alloc_skb(dev
, length
+ NET_IP_ALIGN
, gfp
);
2808 if (NET_IP_ALIGN
&& skb
)
2809 skb_reserve(skb
, NET_IP_ALIGN
);
2813 static inline struct sk_buff
*netdev_alloc_skb_ip_align(struct net_device
*dev
,
2814 unsigned int length
)
2816 return __netdev_alloc_skb_ip_align(dev
, length
, GFP_ATOMIC
);
2819 static inline void skb_free_frag(void *addr
)
2821 page_frag_free(addr
);
2824 void *napi_alloc_frag(unsigned int fragsz
);
2825 struct sk_buff
*__napi_alloc_skb(struct napi_struct
*napi
,
2826 unsigned int length
, gfp_t gfp_mask
);
2827 static inline struct sk_buff
*napi_alloc_skb(struct napi_struct
*napi
,
2828 unsigned int length
)
2830 return __napi_alloc_skb(napi
, length
, GFP_ATOMIC
);
2832 void napi_consume_skb(struct sk_buff
*skb
, int budget
);
2834 void __kfree_skb_flush(void);
2835 void __kfree_skb_defer(struct sk_buff
*skb
);
2838 * __dev_alloc_pages - allocate page for network Rx
2839 * @gfp_mask: allocation priority. Set __GFP_NOMEMALLOC if not for network Rx
2840 * @order: size of the allocation
2842 * Allocate a new page.
2844 * %NULL is returned if there is no free memory.
2846 static inline struct page
*__dev_alloc_pages(gfp_t gfp_mask
,
2849 /* This piece of code contains several assumptions.
2850 * 1. This is for device Rx, therefor a cold page is preferred.
2851 * 2. The expectation is the user wants a compound page.
2852 * 3. If requesting a order 0 page it will not be compound
2853 * due to the check to see if order has a value in prep_new_page
2854 * 4. __GFP_MEMALLOC is ignored if __GFP_NOMEMALLOC is set due to
2855 * code in gfp_to_alloc_flags that should be enforcing this.
2857 gfp_mask
|= __GFP_COMP
| __GFP_MEMALLOC
;
2859 return alloc_pages_node(NUMA_NO_NODE
, gfp_mask
, order
);
2862 static inline struct page
*dev_alloc_pages(unsigned int order
)
2864 return __dev_alloc_pages(GFP_ATOMIC
| __GFP_NOWARN
, order
);
2868 * __dev_alloc_page - allocate a page for network Rx
2869 * @gfp_mask: allocation priority. Set __GFP_NOMEMALLOC if not for network Rx
2871 * Allocate a new page.
2873 * %NULL is returned if there is no free memory.
2875 static inline struct page
*__dev_alloc_page(gfp_t gfp_mask
)
2877 return __dev_alloc_pages(gfp_mask
, 0);
2880 static inline struct page
*dev_alloc_page(void)
2882 return dev_alloc_pages(0);
2886 * skb_propagate_pfmemalloc - Propagate pfmemalloc if skb is allocated after RX page
2887 * @page: The page that was allocated from skb_alloc_page
2888 * @skb: The skb that may need pfmemalloc set
2890 static inline void skb_propagate_pfmemalloc(struct page
*page
,
2891 struct sk_buff
*skb
)
2893 if (page_is_pfmemalloc(page
))
2894 skb
->pfmemalloc
= true;
2898 * skb_frag_off() - Returns the offset of a skb fragment
2899 * @frag: the paged fragment
2901 static inline unsigned int skb_frag_off(const skb_frag_t
*frag
)
2903 return frag
->bv_offset
;
2907 * skb_frag_off_add() - Increments the offset of a skb fragment by @delta
2908 * @frag: skb fragment
2909 * @delta: value to add
2911 static inline void skb_frag_off_add(skb_frag_t
*frag
, int delta
)
2913 frag
->bv_offset
+= delta
;
2917 * skb_frag_off_set() - Sets the offset of a skb fragment
2918 * @frag: skb fragment
2919 * @offset: offset of fragment
2921 static inline void skb_frag_off_set(skb_frag_t
*frag
, unsigned int offset
)
2923 frag
->bv_offset
= offset
;
2927 * skb_frag_off_copy() - Sets the offset of a skb fragment from another fragment
2928 * @fragto: skb fragment where offset is set
2929 * @fragfrom: skb fragment offset is copied from
2931 static inline void skb_frag_off_copy(skb_frag_t
*fragto
,
2932 const skb_frag_t
*fragfrom
)
2934 fragto
->bv_offset
= fragfrom
->bv_offset
;
2938 * skb_frag_page - retrieve the page referred to by a paged fragment
2939 * @frag: the paged fragment
2941 * Returns the &struct page associated with @frag.
2943 static inline struct page
*skb_frag_page(const skb_frag_t
*frag
)
2945 return frag
->bv_page
;
2949 * __skb_frag_ref - take an addition reference on a paged fragment.
2950 * @frag: the paged fragment
2952 * Takes an additional reference on the paged fragment @frag.
2954 static inline void __skb_frag_ref(skb_frag_t
*frag
)
2956 get_page(skb_frag_page(frag
));
2960 * skb_frag_ref - take an addition reference on a paged fragment of an skb.
2962 * @f: the fragment offset.
2964 * Takes an additional reference on the @f'th paged fragment of @skb.
2966 static inline void skb_frag_ref(struct sk_buff
*skb
, int f
)
2968 __skb_frag_ref(&skb_shinfo(skb
)->frags
[f
]);
2972 * __skb_frag_unref - release a reference on a paged fragment.
2973 * @frag: the paged fragment
2975 * Releases a reference on the paged fragment @frag.
2977 static inline void __skb_frag_unref(skb_frag_t
*frag
)
2979 put_page(skb_frag_page(frag
));
2983 * skb_frag_unref - release a reference on a paged fragment of an skb.
2985 * @f: the fragment offset
2987 * Releases a reference on the @f'th paged fragment of @skb.
2989 static inline void skb_frag_unref(struct sk_buff
*skb
, int f
)
2991 __skb_frag_unref(&skb_shinfo(skb
)->frags
[f
]);
2995 * skb_frag_address - gets the address of the data contained in a paged fragment
2996 * @frag: the paged fragment buffer
2998 * Returns the address of the data within @frag. The page must already
3001 static inline void *skb_frag_address(const skb_frag_t
*frag
)
3003 return page_address(skb_frag_page(frag
)) + skb_frag_off(frag
);
3007 * skb_frag_address_safe - gets the address of the data contained in a paged fragment
3008 * @frag: the paged fragment buffer
3010 * Returns the address of the data within @frag. Checks that the page
3011 * is mapped and returns %NULL otherwise.
3013 static inline void *skb_frag_address_safe(const skb_frag_t
*frag
)
3015 void *ptr
= page_address(skb_frag_page(frag
));
3019 return ptr
+ skb_frag_off(frag
);
3023 * skb_frag_page_copy() - sets the page in a fragment from another fragment
3024 * @fragto: skb fragment where page is set
3025 * @fragfrom: skb fragment page is copied from
3027 static inline void skb_frag_page_copy(skb_frag_t
*fragto
,
3028 const skb_frag_t
*fragfrom
)
3030 fragto
->bv_page
= fragfrom
->bv_page
;
3034 * __skb_frag_set_page - sets the page contained in a paged fragment
3035 * @frag: the paged fragment
3036 * @page: the page to set
3038 * Sets the fragment @frag to contain @page.
3040 static inline void __skb_frag_set_page(skb_frag_t
*frag
, struct page
*page
)
3042 frag
->bv_page
= page
;
3046 * skb_frag_set_page - sets the page contained in a paged fragment of an skb
3048 * @f: the fragment offset
3049 * @page: the page to set
3051 * Sets the @f'th fragment of @skb to contain @page.
3053 static inline void skb_frag_set_page(struct sk_buff
*skb
, int f
,
3056 __skb_frag_set_page(&skb_shinfo(skb
)->frags
[f
], page
);
3059 bool skb_page_frag_refill(unsigned int sz
, struct page_frag
*pfrag
, gfp_t prio
);
3062 * skb_frag_dma_map - maps a paged fragment via the DMA API
3063 * @dev: the device to map the fragment to
3064 * @frag: the paged fragment to map
3065 * @offset: the offset within the fragment (starting at the
3066 * fragment's own offset)
3067 * @size: the number of bytes to map
3068 * @dir: the direction of the mapping (``PCI_DMA_*``)
3070 * Maps the page associated with @frag to @device.
3072 static inline dma_addr_t
skb_frag_dma_map(struct device
*dev
,
3073 const skb_frag_t
*frag
,
3074 size_t offset
, size_t size
,
3075 enum dma_data_direction dir
)
3077 return dma_map_page(dev
, skb_frag_page(frag
),
3078 skb_frag_off(frag
) + offset
, size
, dir
);
3081 static inline struct sk_buff
*pskb_copy(struct sk_buff
*skb
,
3084 return __pskb_copy(skb
, skb_headroom(skb
), gfp_mask
);
3088 static inline struct sk_buff
*pskb_copy_for_clone(struct sk_buff
*skb
,
3091 return __pskb_copy_fclone(skb
, skb_headroom(skb
), gfp_mask
, true);
3096 * skb_clone_writable - is the header of a clone writable
3097 * @skb: buffer to check
3098 * @len: length up to which to write
3100 * Returns true if modifying the header part of the cloned buffer
3101 * does not requires the data to be copied.
3103 static inline int skb_clone_writable(const struct sk_buff
*skb
, unsigned int len
)
3105 return !skb_header_cloned(skb
) &&
3106 skb_headroom(skb
) + len
<= skb
->hdr_len
;
3109 static inline int skb_try_make_writable(struct sk_buff
*skb
,
3110 unsigned int write_len
)
3112 return skb_cloned(skb
) && !skb_clone_writable(skb
, write_len
) &&
3113 pskb_expand_head(skb
, 0, 0, GFP_ATOMIC
);
3116 static inline int __skb_cow(struct sk_buff
*skb
, unsigned int headroom
,
3121 if (headroom
> skb_headroom(skb
))
3122 delta
= headroom
- skb_headroom(skb
);
3124 if (delta
|| cloned
)
3125 return pskb_expand_head(skb
, ALIGN(delta
, NET_SKB_PAD
), 0,
3131 * skb_cow - copy header of skb when it is required
3132 * @skb: buffer to cow
3133 * @headroom: needed headroom
3135 * If the skb passed lacks sufficient headroom or its data part
3136 * is shared, data is reallocated. If reallocation fails, an error
3137 * is returned and original skb is not changed.
3139 * The result is skb with writable area skb->head...skb->tail
3140 * and at least @headroom of space at head.
3142 static inline int skb_cow(struct sk_buff
*skb
, unsigned int headroom
)
3144 return __skb_cow(skb
, headroom
, skb_cloned(skb
));
3148 * skb_cow_head - skb_cow but only making the head writable
3149 * @skb: buffer to cow
3150 * @headroom: needed headroom
3152 * This function is identical to skb_cow except that we replace the
3153 * skb_cloned check by skb_header_cloned. It should be used when
3154 * you only need to push on some header and do not need to modify
3157 static inline int skb_cow_head(struct sk_buff
*skb
, unsigned int headroom
)
3159 return __skb_cow(skb
, headroom
, skb_header_cloned(skb
));
3163 * skb_padto - pad an skbuff up to a minimal size
3164 * @skb: buffer to pad
3165 * @len: minimal length
3167 * Pads up a buffer to ensure the trailing bytes exist and are
3168 * blanked. If the buffer already contains sufficient data it
3169 * is untouched. Otherwise it is extended. Returns zero on
3170 * success. The skb is freed on error.
3172 static inline int skb_padto(struct sk_buff
*skb
, unsigned int len
)
3174 unsigned int size
= skb
->len
;
3175 if (likely(size
>= len
))
3177 return skb_pad(skb
, len
- size
);
3181 * __skb_put_padto - increase size and pad an skbuff up to a minimal size
3182 * @skb: buffer to pad
3183 * @len: minimal length
3184 * @free_on_error: free buffer on error
3186 * Pads up a buffer to ensure the trailing bytes exist and are
3187 * blanked. If the buffer already contains sufficient data it
3188 * is untouched. Otherwise it is extended. Returns zero on
3189 * success. The skb is freed on error if @free_on_error is true.
3191 static inline int __skb_put_padto(struct sk_buff
*skb
, unsigned int len
,
3194 unsigned int size
= skb
->len
;
3196 if (unlikely(size
< len
)) {
3198 if (__skb_pad(skb
, len
, free_on_error
))
3200 __skb_put(skb
, len
);
3206 * skb_put_padto - increase size and pad an skbuff up to a minimal size
3207 * @skb: buffer to pad
3208 * @len: minimal length
3210 * Pads up a buffer to ensure the trailing bytes exist and are
3211 * blanked. If the buffer already contains sufficient data it
3212 * is untouched. Otherwise it is extended. Returns zero on
3213 * success. The skb is freed on error.
3215 static inline int skb_put_padto(struct sk_buff
*skb
, unsigned int len
)
3217 return __skb_put_padto(skb
, len
, true);
3220 static inline int skb_add_data(struct sk_buff
*skb
,
3221 struct iov_iter
*from
, int copy
)
3223 const int off
= skb
->len
;
3225 if (skb
->ip_summed
== CHECKSUM_NONE
) {
3227 if (csum_and_copy_from_iter_full(skb_put(skb
, copy
), copy
,
3229 skb
->csum
= csum_block_add(skb
->csum
, csum
, off
);
3232 } else if (copy_from_iter_full(skb_put(skb
, copy
), copy
, from
))
3235 __skb_trim(skb
, off
);
3239 static inline bool skb_can_coalesce(struct sk_buff
*skb
, int i
,
3240 const struct page
*page
, int off
)
3245 const skb_frag_t
*frag
= &skb_shinfo(skb
)->frags
[i
- 1];
3247 return page
== skb_frag_page(frag
) &&
3248 off
== skb_frag_off(frag
) + skb_frag_size(frag
);
3253 static inline int __skb_linearize(struct sk_buff
*skb
)
3255 return __pskb_pull_tail(skb
, skb
->data_len
) ? 0 : -ENOMEM
;
3259 * skb_linearize - convert paged skb to linear one
3260 * @skb: buffer to linarize
3262 * If there is no free memory -ENOMEM is returned, otherwise zero
3263 * is returned and the old skb data released.
3265 static inline int skb_linearize(struct sk_buff
*skb
)
3267 return skb_is_nonlinear(skb
) ? __skb_linearize(skb
) : 0;
3271 * skb_has_shared_frag - can any frag be overwritten
3272 * @skb: buffer to test
3274 * Return true if the skb has at least one frag that might be modified
3275 * by an external entity (as in vmsplice()/sendfile())
3277 static inline bool skb_has_shared_frag(const struct sk_buff
*skb
)
3279 return skb_is_nonlinear(skb
) &&
3280 skb_shinfo(skb
)->tx_flags
& SKBTX_SHARED_FRAG
;
3284 * skb_linearize_cow - make sure skb is linear and writable
3285 * @skb: buffer to process
3287 * If there is no free memory -ENOMEM is returned, otherwise zero
3288 * is returned and the old skb data released.
3290 static inline int skb_linearize_cow(struct sk_buff
*skb
)
3292 return skb_is_nonlinear(skb
) || skb_cloned(skb
) ?
3293 __skb_linearize(skb
) : 0;
3296 static __always_inline
void
3297 __skb_postpull_rcsum(struct sk_buff
*skb
, const void *start
, unsigned int len
,
3300 if (skb
->ip_summed
== CHECKSUM_COMPLETE
)
3301 skb
->csum
= csum_block_sub(skb
->csum
,
3302 csum_partial(start
, len
, 0), off
);
3303 else if (skb
->ip_summed
== CHECKSUM_PARTIAL
&&
3304 skb_checksum_start_offset(skb
) < 0)
3305 skb
->ip_summed
= CHECKSUM_NONE
;
3309 * skb_postpull_rcsum - update checksum for received skb after pull
3310 * @skb: buffer to update
3311 * @start: start of data before pull
3312 * @len: length of data pulled
3314 * After doing a pull on a received packet, you need to call this to
3315 * update the CHECKSUM_COMPLETE checksum, or set ip_summed to
3316 * CHECKSUM_NONE so that it can be recomputed from scratch.
3318 static inline void skb_postpull_rcsum(struct sk_buff
*skb
,
3319 const void *start
, unsigned int len
)
3321 __skb_postpull_rcsum(skb
, start
, len
, 0);
3324 static __always_inline
void
3325 __skb_postpush_rcsum(struct sk_buff
*skb
, const void *start
, unsigned int len
,
3328 if (skb
->ip_summed
== CHECKSUM_COMPLETE
)
3329 skb
->csum
= csum_block_add(skb
->csum
,
3330 csum_partial(start
, len
, 0), off
);
3334 * skb_postpush_rcsum - update checksum for received skb after push
3335 * @skb: buffer to update
3336 * @start: start of data after push
3337 * @len: length of data pushed
3339 * After doing a push on a received packet, you need to call this to
3340 * update the CHECKSUM_COMPLETE checksum.
3342 static inline void skb_postpush_rcsum(struct sk_buff
*skb
,
3343 const void *start
, unsigned int len
)
3345 __skb_postpush_rcsum(skb
, start
, len
, 0);
3348 void *skb_pull_rcsum(struct sk_buff
*skb
, unsigned int len
);
3351 * skb_push_rcsum - push skb and update receive checksum
3352 * @skb: buffer to update
3353 * @len: length of data pulled
3355 * This function performs an skb_push on the packet and updates
3356 * the CHECKSUM_COMPLETE checksum. It should be used on
3357 * receive path processing instead of skb_push unless you know
3358 * that the checksum difference is zero (e.g., a valid IP header)
3359 * or you are setting ip_summed to CHECKSUM_NONE.
3361 static inline void *skb_push_rcsum(struct sk_buff
*skb
, unsigned int len
)
3364 skb_postpush_rcsum(skb
, skb
->data
, len
);
3368 int pskb_trim_rcsum_slow(struct sk_buff
*skb
, unsigned int len
);
3370 * pskb_trim_rcsum - trim received skb and update checksum
3371 * @skb: buffer to trim
3374 * This is exactly the same as pskb_trim except that it ensures the
3375 * checksum of received packets are still valid after the operation.
3376 * It can change skb pointers.
3379 static inline int pskb_trim_rcsum(struct sk_buff
*skb
, unsigned int len
)
3381 if (likely(len
>= skb
->len
))
3383 return pskb_trim_rcsum_slow(skb
, len
);
3386 static inline int __skb_trim_rcsum(struct sk_buff
*skb
, unsigned int len
)
3388 if (skb
->ip_summed
== CHECKSUM_COMPLETE
)
3389 skb
->ip_summed
= CHECKSUM_NONE
;
3390 __skb_trim(skb
, len
);
3394 static inline int __skb_grow_rcsum(struct sk_buff
*skb
, unsigned int len
)
3396 if (skb
->ip_summed
== CHECKSUM_COMPLETE
)
3397 skb
->ip_summed
= CHECKSUM_NONE
;
3398 return __skb_grow(skb
, len
);
3401 #define rb_to_skb(rb) rb_entry_safe(rb, struct sk_buff, rbnode)
3402 #define skb_rb_first(root) rb_to_skb(rb_first(root))
3403 #define skb_rb_last(root) rb_to_skb(rb_last(root))
3404 #define skb_rb_next(skb) rb_to_skb(rb_next(&(skb)->rbnode))
3405 #define skb_rb_prev(skb) rb_to_skb(rb_prev(&(skb)->rbnode))
3407 #define skb_queue_walk(queue, skb) \
3408 for (skb = (queue)->next; \
3409 skb != (struct sk_buff *)(queue); \
3412 #define skb_queue_walk_safe(queue, skb, tmp) \
3413 for (skb = (queue)->next, tmp = skb->next; \
3414 skb != (struct sk_buff *)(queue); \
3415 skb = tmp, tmp = skb->next)
3417 #define skb_queue_walk_from(queue, skb) \
3418 for (; skb != (struct sk_buff *)(queue); \
3421 #define skb_rbtree_walk(skb, root) \
3422 for (skb = skb_rb_first(root); skb != NULL; \
3423 skb = skb_rb_next(skb))
3425 #define skb_rbtree_walk_from(skb) \
3426 for (; skb != NULL; \
3427 skb = skb_rb_next(skb))
3429 #define skb_rbtree_walk_from_safe(skb, tmp) \
3430 for (; tmp = skb ? skb_rb_next(skb) : NULL, (skb != NULL); \
3433 #define skb_queue_walk_from_safe(queue, skb, tmp) \
3434 for (tmp = skb->next; \
3435 skb != (struct sk_buff *)(queue); \
3436 skb = tmp, tmp = skb->next)
3438 #define skb_queue_reverse_walk(queue, skb) \
3439 for (skb = (queue)->prev; \
3440 skb != (struct sk_buff *)(queue); \
3443 #define skb_queue_reverse_walk_safe(queue, skb, tmp) \
3444 for (skb = (queue)->prev, tmp = skb->prev; \
3445 skb != (struct sk_buff *)(queue); \
3446 skb = tmp, tmp = skb->prev)
3448 #define skb_queue_reverse_walk_from_safe(queue, skb, tmp) \
3449 for (tmp = skb->prev; \
3450 skb != (struct sk_buff *)(queue); \
3451 skb = tmp, tmp = skb->prev)
3453 static inline bool skb_has_frag_list(const struct sk_buff
*skb
)
3455 return skb_shinfo(skb
)->frag_list
!= NULL
;
3458 static inline void skb_frag_list_init(struct sk_buff
*skb
)
3460 skb_shinfo(skb
)->frag_list
= NULL
;
3463 #define skb_walk_frags(skb, iter) \
3464 for (iter = skb_shinfo(skb)->frag_list; iter; iter = iter->next)
3467 int __skb_wait_for_more_packets(struct sock
*sk
, int *err
, long *timeo_p
,
3468 const struct sk_buff
*skb
);
3469 struct sk_buff
*__skb_try_recv_from_queue(struct sock
*sk
,
3470 struct sk_buff_head
*queue
,
3472 void (*destructor
)(struct sock
*sk
,
3473 struct sk_buff
*skb
),
3475 struct sk_buff
**last
);
3476 struct sk_buff
*__skb_try_recv_datagram(struct sock
*sk
, unsigned flags
,
3477 void (*destructor
)(struct sock
*sk
,
3478 struct sk_buff
*skb
),
3480 struct sk_buff
**last
);
3481 struct sk_buff
*__skb_recv_datagram(struct sock
*sk
, unsigned flags
,
3482 void (*destructor
)(struct sock
*sk
,
3483 struct sk_buff
*skb
),
3484 int *off
, int *err
);
3485 struct sk_buff
*skb_recv_datagram(struct sock
*sk
, unsigned flags
, int noblock
,
3487 __poll_t
datagram_poll(struct file
*file
, struct socket
*sock
,
3488 struct poll_table_struct
*wait
);
3489 int skb_copy_datagram_iter(const struct sk_buff
*from
, int offset
,
3490 struct iov_iter
*to
, int size
);
3491 static inline int skb_copy_datagram_msg(const struct sk_buff
*from
, int offset
,
3492 struct msghdr
*msg
, int size
)
3494 return skb_copy_datagram_iter(from
, offset
, &msg
->msg_iter
, size
);
3496 int skb_copy_and_csum_datagram_msg(struct sk_buff
*skb
, int hlen
,
3497 struct msghdr
*msg
);
3498 int skb_copy_and_hash_datagram_iter(const struct sk_buff
*skb
, int offset
,
3499 struct iov_iter
*to
, int len
,
3500 struct ahash_request
*hash
);
3501 int skb_copy_datagram_from_iter(struct sk_buff
*skb
, int offset
,
3502 struct iov_iter
*from
, int len
);
3503 int zerocopy_sg_from_iter(struct sk_buff
*skb
, struct iov_iter
*frm
);
3504 void skb_free_datagram(struct sock
*sk
, struct sk_buff
*skb
);
3505 void __skb_free_datagram_locked(struct sock
*sk
, struct sk_buff
*skb
, int len
);
3506 static inline void skb_free_datagram_locked(struct sock
*sk
,
3507 struct sk_buff
*skb
)
3509 __skb_free_datagram_locked(sk
, skb
, 0);
3511 int skb_kill_datagram(struct sock
*sk
, struct sk_buff
*skb
, unsigned int flags
);
3512 int skb_copy_bits(const struct sk_buff
*skb
, int offset
, void *to
, int len
);
3513 int skb_store_bits(struct sk_buff
*skb
, int offset
, const void *from
, int len
);
3514 __wsum
skb_copy_and_csum_bits(const struct sk_buff
*skb
, int offset
, u8
*to
,
3515 int len
, __wsum csum
);
3516 int skb_splice_bits(struct sk_buff
*skb
, struct sock
*sk
, unsigned int offset
,
3517 struct pipe_inode_info
*pipe
, unsigned int len
,
3518 unsigned int flags
);
3519 int skb_send_sock_locked(struct sock
*sk
, struct sk_buff
*skb
, int offset
,
3521 void skb_copy_and_csum_dev(const struct sk_buff
*skb
, u8
*to
);
3522 unsigned int skb_zerocopy_headlen(const struct sk_buff
*from
);
3523 int skb_zerocopy(struct sk_buff
*to
, struct sk_buff
*from
,
3525 void skb_split(struct sk_buff
*skb
, struct sk_buff
*skb1
, const u32 len
);
3526 int skb_shift(struct sk_buff
*tgt
, struct sk_buff
*skb
, int shiftlen
);
3527 void skb_scrub_packet(struct sk_buff
*skb
, bool xnet
);
3528 bool skb_gso_validate_network_len(const struct sk_buff
*skb
, unsigned int mtu
);
3529 bool skb_gso_validate_mac_len(const struct sk_buff
*skb
, unsigned int len
);
3530 struct sk_buff
*skb_segment(struct sk_buff
*skb
, netdev_features_t features
);
3531 struct sk_buff
*skb_vlan_untag(struct sk_buff
*skb
);
3532 int skb_ensure_writable(struct sk_buff
*skb
, int write_len
);
3533 int __skb_vlan_pop(struct sk_buff
*skb
, u16
*vlan_tci
);
3534 int skb_vlan_pop(struct sk_buff
*skb
);
3535 int skb_vlan_push(struct sk_buff
*skb
, __be16 vlan_proto
, u16 vlan_tci
);
3536 int skb_mpls_push(struct sk_buff
*skb
, __be32 mpls_lse
, __be16 mpls_proto
,
3537 int mac_len
, bool ethernet
);
3538 int skb_mpls_pop(struct sk_buff
*skb
, __be16 next_proto
, int mac_len
,
3540 int skb_mpls_update_lse(struct sk_buff
*skb
, __be32 mpls_lse
);
3541 int skb_mpls_dec_ttl(struct sk_buff
*skb
);
3542 struct sk_buff
*pskb_extract(struct sk_buff
*skb
, int off
, int to_copy
,
3545 static inline int memcpy_from_msg(void *data
, struct msghdr
*msg
, int len
)
3547 return copy_from_iter_full(data
, len
, &msg
->msg_iter
) ? 0 : -EFAULT
;
3550 static inline int memcpy_to_msg(struct msghdr
*msg
, void *data
, int len
)
3552 return copy_to_iter(data
, len
, &msg
->msg_iter
) == len
? 0 : -EFAULT
;
3555 struct skb_checksum_ops
{
3556 __wsum (*update
)(const void *mem
, int len
, __wsum wsum
);
3557 __wsum (*combine
)(__wsum csum
, __wsum csum2
, int offset
, int len
);
3560 extern const struct skb_checksum_ops
*crc32c_csum_stub __read_mostly
;
3562 __wsum
__skb_checksum(const struct sk_buff
*skb
, int offset
, int len
,
3563 __wsum csum
, const struct skb_checksum_ops
*ops
);
3564 __wsum
skb_checksum(const struct sk_buff
*skb
, int offset
, int len
,
3567 static inline void * __must_check
3568 __skb_header_pointer(const struct sk_buff
*skb
, int offset
,
3569 int len
, void *data
, int hlen
, void *buffer
)
3571 if (hlen
- offset
>= len
)
3572 return data
+ offset
;
3575 skb_copy_bits(skb
, offset
, buffer
, len
) < 0)
3581 static inline void * __must_check
3582 skb_header_pointer(const struct sk_buff
*skb
, int offset
, int len
, void *buffer
)
3584 return __skb_header_pointer(skb
, offset
, len
, skb
->data
,
3585 skb_headlen(skb
), buffer
);
3589 * skb_needs_linearize - check if we need to linearize a given skb
3590 * depending on the given device features.
3591 * @skb: socket buffer to check
3592 * @features: net device features
3594 * Returns true if either:
3595 * 1. skb has frag_list and the device doesn't support FRAGLIST, or
3596 * 2. skb is fragmented and the device does not support SG.
3598 static inline bool skb_needs_linearize(struct sk_buff
*skb
,
3599 netdev_features_t features
)
3601 return skb_is_nonlinear(skb
) &&
3602 ((skb_has_frag_list(skb
) && !(features
& NETIF_F_FRAGLIST
)) ||
3603 (skb_shinfo(skb
)->nr_frags
&& !(features
& NETIF_F_SG
)));
3606 static inline void skb_copy_from_linear_data(const struct sk_buff
*skb
,
3608 const unsigned int len
)
3610 memcpy(to
, skb
->data
, len
);
3613 static inline void skb_copy_from_linear_data_offset(const struct sk_buff
*skb
,
3614 const int offset
, void *to
,
3615 const unsigned int len
)
3617 memcpy(to
, skb
->data
+ offset
, len
);
3620 static inline void skb_copy_to_linear_data(struct sk_buff
*skb
,
3622 const unsigned int len
)
3624 memcpy(skb
->data
, from
, len
);
3627 static inline void skb_copy_to_linear_data_offset(struct sk_buff
*skb
,
3630 const unsigned int len
)
3632 memcpy(skb
->data
+ offset
, from
, len
);
3635 void skb_init(void);
3637 static inline ktime_t
skb_get_ktime(const struct sk_buff
*skb
)
3643 * skb_get_timestamp - get timestamp from a skb
3644 * @skb: skb to get stamp from
3645 * @stamp: pointer to struct __kernel_old_timeval to store stamp in
3647 * Timestamps are stored in the skb as offsets to a base timestamp.
3648 * This function converts the offset back to a struct timeval and stores
3651 static inline void skb_get_timestamp(const struct sk_buff
*skb
,
3652 struct __kernel_old_timeval
*stamp
)
3654 *stamp
= ns_to_kernel_old_timeval(skb
->tstamp
);
3657 static inline void skb_get_new_timestamp(const struct sk_buff
*skb
,
3658 struct __kernel_sock_timeval
*stamp
)
3660 struct timespec64 ts
= ktime_to_timespec64(skb
->tstamp
);
3662 stamp
->tv_sec
= ts
.tv_sec
;
3663 stamp
->tv_usec
= ts
.tv_nsec
/ 1000;
3666 static inline void skb_get_timestampns(const struct sk_buff
*skb
,
3667 struct __kernel_old_timespec
*stamp
)
3669 struct timespec64 ts
= ktime_to_timespec64(skb
->tstamp
);
3671 stamp
->tv_sec
= ts
.tv_sec
;
3672 stamp
->tv_nsec
= ts
.tv_nsec
;
3675 static inline void skb_get_new_timestampns(const struct sk_buff
*skb
,
3676 struct __kernel_timespec
*stamp
)
3678 struct timespec64 ts
= ktime_to_timespec64(skb
->tstamp
);
3680 stamp
->tv_sec
= ts
.tv_sec
;
3681 stamp
->tv_nsec
= ts
.tv_nsec
;
3684 static inline void __net_timestamp(struct sk_buff
*skb
)
3686 skb
->tstamp
= ktime_get_real();
3689 static inline ktime_t
net_timedelta(ktime_t t
)
3691 return ktime_sub(ktime_get_real(), t
);
3694 static inline ktime_t
net_invalid_timestamp(void)
3699 static inline u8
skb_metadata_len(const struct sk_buff
*skb
)
3701 return skb_shinfo(skb
)->meta_len
;
3704 static inline void *skb_metadata_end(const struct sk_buff
*skb
)
3706 return skb_mac_header(skb
);
3709 static inline bool __skb_metadata_differs(const struct sk_buff
*skb_a
,
3710 const struct sk_buff
*skb_b
,
3713 const void *a
= skb_metadata_end(skb_a
);
3714 const void *b
= skb_metadata_end(skb_b
);
3715 /* Using more efficient varaiant than plain call to memcmp(). */
3716 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
3720 #define __it(x, op) (x -= sizeof(u##op))
3721 #define __it_diff(a, b, op) (*(u##op *)__it(a, op)) ^ (*(u##op *)__it(b, op))
3722 case 32: diffs
|= __it_diff(a
, b
, 64);
3724 case 24: diffs
|= __it_diff(a
, b
, 64);
3726 case 16: diffs
|= __it_diff(a
, b
, 64);
3728 case 8: diffs
|= __it_diff(a
, b
, 64);
3730 case 28: diffs
|= __it_diff(a
, b
, 64);
3732 case 20: diffs
|= __it_diff(a
, b
, 64);
3734 case 12: diffs
|= __it_diff(a
, b
, 64);
3736 case 4: diffs
|= __it_diff(a
, b
, 32);
3741 return memcmp(a
- meta_len
, b
- meta_len
, meta_len
);
3745 static inline bool skb_metadata_differs(const struct sk_buff
*skb_a
,
3746 const struct sk_buff
*skb_b
)
3748 u8 len_a
= skb_metadata_len(skb_a
);
3749 u8 len_b
= skb_metadata_len(skb_b
);
3751 if (!(len_a
| len_b
))
3754 return len_a
!= len_b
?
3755 true : __skb_metadata_differs(skb_a
, skb_b
, len_a
);
3758 static inline void skb_metadata_set(struct sk_buff
*skb
, u8 meta_len
)
3760 skb_shinfo(skb
)->meta_len
= meta_len
;
3763 static inline void skb_metadata_clear(struct sk_buff
*skb
)
3765 skb_metadata_set(skb
, 0);
3768 struct sk_buff
*skb_clone_sk(struct sk_buff
*skb
);
3770 #ifdef CONFIG_NETWORK_PHY_TIMESTAMPING
3772 void skb_clone_tx_timestamp(struct sk_buff
*skb
);
3773 bool skb_defer_rx_timestamp(struct sk_buff
*skb
);
3775 #else /* CONFIG_NETWORK_PHY_TIMESTAMPING */
3777 static inline void skb_clone_tx_timestamp(struct sk_buff
*skb
)
3781 static inline bool skb_defer_rx_timestamp(struct sk_buff
*skb
)
3786 #endif /* !CONFIG_NETWORK_PHY_TIMESTAMPING */
3789 * skb_complete_tx_timestamp() - deliver cloned skb with tx timestamps
3791 * PHY drivers may accept clones of transmitted packets for
3792 * timestamping via their phy_driver.txtstamp method. These drivers
3793 * must call this function to return the skb back to the stack with a
3796 * @skb: clone of the the original outgoing packet
3797 * @hwtstamps: hardware time stamps
3800 void skb_complete_tx_timestamp(struct sk_buff
*skb
,
3801 struct skb_shared_hwtstamps
*hwtstamps
);
3803 void __skb_tstamp_tx(struct sk_buff
*orig_skb
,
3804 struct skb_shared_hwtstamps
*hwtstamps
,
3805 struct sock
*sk
, int tstype
);
3808 * skb_tstamp_tx - queue clone of skb with send time stamps
3809 * @orig_skb: the original outgoing packet
3810 * @hwtstamps: hardware time stamps, may be NULL if not available
3812 * If the skb has a socket associated, then this function clones the
3813 * skb (thus sharing the actual data and optional structures), stores
3814 * the optional hardware time stamping information (if non NULL) or
3815 * generates a software time stamp (otherwise), then queues the clone
3816 * to the error queue of the socket. Errors are silently ignored.
3818 void skb_tstamp_tx(struct sk_buff
*orig_skb
,
3819 struct skb_shared_hwtstamps
*hwtstamps
);
3822 * skb_tx_timestamp() - Driver hook for transmit timestamping
3824 * Ethernet MAC Drivers should call this function in their hard_xmit()
3825 * function immediately before giving the sk_buff to the MAC hardware.
3827 * Specifically, one should make absolutely sure that this function is
3828 * called before TX completion of this packet can trigger. Otherwise
3829 * the packet could potentially already be freed.
3831 * @skb: A socket buffer.
3833 static inline void skb_tx_timestamp(struct sk_buff
*skb
)
3835 skb_clone_tx_timestamp(skb
);
3836 if (skb_shinfo(skb
)->tx_flags
& SKBTX_SW_TSTAMP
)
3837 skb_tstamp_tx(skb
, NULL
);
3841 * skb_complete_wifi_ack - deliver skb with wifi status
3843 * @skb: the original outgoing packet
3844 * @acked: ack status
3847 void skb_complete_wifi_ack(struct sk_buff
*skb
, bool acked
);
3849 __sum16
__skb_checksum_complete_head(struct sk_buff
*skb
, int len
);
3850 __sum16
__skb_checksum_complete(struct sk_buff
*skb
);
3852 static inline int skb_csum_unnecessary(const struct sk_buff
*skb
)
3854 return ((skb
->ip_summed
== CHECKSUM_UNNECESSARY
) ||
3856 (skb
->ip_summed
== CHECKSUM_PARTIAL
&&
3857 skb_checksum_start_offset(skb
) >= 0));
3861 * skb_checksum_complete - Calculate checksum of an entire packet
3862 * @skb: packet to process
3864 * This function calculates the checksum over the entire packet plus
3865 * the value of skb->csum. The latter can be used to supply the
3866 * checksum of a pseudo header as used by TCP/UDP. It returns the
3869 * For protocols that contain complete checksums such as ICMP/TCP/UDP,
3870 * this function can be used to verify that checksum on received
3871 * packets. In that case the function should return zero if the
3872 * checksum is correct. In particular, this function will return zero
3873 * if skb->ip_summed is CHECKSUM_UNNECESSARY which indicates that the
3874 * hardware has already verified the correctness of the checksum.
3876 static inline __sum16
skb_checksum_complete(struct sk_buff
*skb
)
3878 return skb_csum_unnecessary(skb
) ?
3879 0 : __skb_checksum_complete(skb
);
3882 static inline void __skb_decr_checksum_unnecessary(struct sk_buff
*skb
)
3884 if (skb
->ip_summed
== CHECKSUM_UNNECESSARY
) {
3885 if (skb
->csum_level
== 0)
3886 skb
->ip_summed
= CHECKSUM_NONE
;
3892 static inline void __skb_incr_checksum_unnecessary(struct sk_buff
*skb
)
3894 if (skb
->ip_summed
== CHECKSUM_UNNECESSARY
) {
3895 if (skb
->csum_level
< SKB_MAX_CSUM_LEVEL
)
3897 } else if (skb
->ip_summed
== CHECKSUM_NONE
) {
3898 skb
->ip_summed
= CHECKSUM_UNNECESSARY
;
3899 skb
->csum_level
= 0;
3903 /* Check if we need to perform checksum complete validation.
3905 * Returns true if checksum complete is needed, false otherwise
3906 * (either checksum is unnecessary or zero checksum is allowed).
3908 static inline bool __skb_checksum_validate_needed(struct sk_buff
*skb
,
3912 if (skb_csum_unnecessary(skb
) || (zero_okay
&& !check
)) {
3913 skb
->csum_valid
= 1;
3914 __skb_decr_checksum_unnecessary(skb
);
3921 /* For small packets <= CHECKSUM_BREAK perform checksum complete directly
3924 #define CHECKSUM_BREAK 76
3926 /* Unset checksum-complete
3928 * Unset checksum complete can be done when packet is being modified
3929 * (uncompressed for instance) and checksum-complete value is
3932 static inline void skb_checksum_complete_unset(struct sk_buff
*skb
)
3934 if (skb
->ip_summed
== CHECKSUM_COMPLETE
)
3935 skb
->ip_summed
= CHECKSUM_NONE
;
3938 /* Validate (init) checksum based on checksum complete.
3941 * 0: checksum is validated or try to in skb_checksum_complete. In the latter
3942 * case the ip_summed will not be CHECKSUM_UNNECESSARY and the pseudo
3943 * checksum is stored in skb->csum for use in __skb_checksum_complete
3944 * non-zero: value of invalid checksum
3947 static inline __sum16
__skb_checksum_validate_complete(struct sk_buff
*skb
,
3951 if (skb
->ip_summed
== CHECKSUM_COMPLETE
) {
3952 if (!csum_fold(csum_add(psum
, skb
->csum
))) {
3953 skb
->csum_valid
= 1;
3960 if (complete
|| skb
->len
<= CHECKSUM_BREAK
) {
3963 csum
= __skb_checksum_complete(skb
);
3964 skb
->csum_valid
= !csum
;
3971 static inline __wsum
null_compute_pseudo(struct sk_buff
*skb
, int proto
)
3976 /* Perform checksum validate (init). Note that this is a macro since we only
3977 * want to calculate the pseudo header which is an input function if necessary.
3978 * First we try to validate without any computation (checksum unnecessary) and
3979 * then calculate based on checksum complete calling the function to compute
3983 * 0: checksum is validated or try to in skb_checksum_complete
3984 * non-zero: value of invalid checksum
3986 #define __skb_checksum_validate(skb, proto, complete, \
3987 zero_okay, check, compute_pseudo) \
3989 __sum16 __ret = 0; \
3990 skb->csum_valid = 0; \
3991 if (__skb_checksum_validate_needed(skb, zero_okay, check)) \
3992 __ret = __skb_checksum_validate_complete(skb, \
3993 complete, compute_pseudo(skb, proto)); \
3997 #define skb_checksum_init(skb, proto, compute_pseudo) \
3998 __skb_checksum_validate(skb, proto, false, false, 0, compute_pseudo)
4000 #define skb_checksum_init_zero_check(skb, proto, check, compute_pseudo) \
4001 __skb_checksum_validate(skb, proto, false, true, check, compute_pseudo)
4003 #define skb_checksum_validate(skb, proto, compute_pseudo) \
4004 __skb_checksum_validate(skb, proto, true, false, 0, compute_pseudo)
4006 #define skb_checksum_validate_zero_check(skb, proto, check, \
4008 __skb_checksum_validate(skb, proto, true, true, check, compute_pseudo)
4010 #define skb_checksum_simple_validate(skb) \
4011 __skb_checksum_validate(skb, 0, true, false, 0, null_compute_pseudo)
4013 static inline bool __skb_checksum_convert_check(struct sk_buff
*skb
)
4015 return (skb
->ip_summed
== CHECKSUM_NONE
&& skb
->csum_valid
);
4018 static inline void __skb_checksum_convert(struct sk_buff
*skb
, __wsum pseudo
)
4020 skb
->csum
= ~pseudo
;
4021 skb
->ip_summed
= CHECKSUM_COMPLETE
;
4024 #define skb_checksum_try_convert(skb, proto, compute_pseudo) \
4026 if (__skb_checksum_convert_check(skb)) \
4027 __skb_checksum_convert(skb, compute_pseudo(skb, proto)); \
4030 static inline void skb_remcsum_adjust_partial(struct sk_buff
*skb
, void *ptr
,
4031 u16 start
, u16 offset
)
4033 skb
->ip_summed
= CHECKSUM_PARTIAL
;
4034 skb
->csum_start
= ((unsigned char *)ptr
+ start
) - skb
->head
;
4035 skb
->csum_offset
= offset
- start
;
4038 /* Update skbuf and packet to reflect the remote checksum offload operation.
4039 * When called, ptr indicates the starting point for skb->csum when
4040 * ip_summed is CHECKSUM_COMPLETE. If we need create checksum complete
4041 * here, skb_postpull_rcsum is done so skb->csum start is ptr.
4043 static inline void skb_remcsum_process(struct sk_buff
*skb
, void *ptr
,
4044 int start
, int offset
, bool nopartial
)
4049 skb_remcsum_adjust_partial(skb
, ptr
, start
, offset
);
4053 if (unlikely(skb
->ip_summed
!= CHECKSUM_COMPLETE
)) {
4054 __skb_checksum_complete(skb
);
4055 skb_postpull_rcsum(skb
, skb
->data
, ptr
- (void *)skb
->data
);
4058 delta
= remcsum_adjust(ptr
, skb
->csum
, start
, offset
);
4060 /* Adjust skb->csum since we changed the packet */
4061 skb
->csum
= csum_add(skb
->csum
, delta
);
4064 static inline struct nf_conntrack
*skb_nfct(const struct sk_buff
*skb
)
4066 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
4067 return (void *)(skb
->_nfct
& NFCT_PTRMASK
);
4073 static inline unsigned long skb_get_nfct(const struct sk_buff
*skb
)
4075 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
4082 static inline void skb_set_nfct(struct sk_buff
*skb
, unsigned long nfct
)
4084 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
4089 #ifdef CONFIG_SKB_EXTENSIONS
4091 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
4097 #if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
4100 #if IS_ENABLED(CONFIG_MPTCP)
4103 SKB_EXT_NUM
, /* must be last */
4107 * struct skb_ext - sk_buff extensions
4108 * @refcnt: 1 on allocation, deallocated on 0
4109 * @offset: offset to add to @data to obtain extension address
4110 * @chunks: size currently allocated, stored in SKB_EXT_ALIGN_SHIFT units
4111 * @data: start of extension data, variable sized
4113 * Note: offsets/lengths are stored in chunks of 8 bytes, this allows
4114 * to use 'u8' types while allowing up to 2kb worth of extension data.
4118 u8 offset
[SKB_EXT_NUM
]; /* in chunks of 8 bytes */
4119 u8 chunks
; /* same */
4120 char data
[0] __aligned(8);
4123 struct skb_ext
*__skb_ext_alloc(void);
4124 void *__skb_ext_set(struct sk_buff
*skb
, enum skb_ext_id id
,
4125 struct skb_ext
*ext
);
4126 void *skb_ext_add(struct sk_buff
*skb
, enum skb_ext_id id
);
4127 void __skb_ext_del(struct sk_buff
*skb
, enum skb_ext_id id
);
4128 void __skb_ext_put(struct skb_ext
*ext
);
4130 static inline void skb_ext_put(struct sk_buff
*skb
)
4132 if (skb
->active_extensions
)
4133 __skb_ext_put(skb
->extensions
);
4136 static inline void __skb_ext_copy(struct sk_buff
*dst
,
4137 const struct sk_buff
*src
)
4139 dst
->active_extensions
= src
->active_extensions
;
4141 if (src
->active_extensions
) {
4142 struct skb_ext
*ext
= src
->extensions
;
4144 refcount_inc(&ext
->refcnt
);
4145 dst
->extensions
= ext
;
4149 static inline void skb_ext_copy(struct sk_buff
*dst
, const struct sk_buff
*src
)
4152 __skb_ext_copy(dst
, src
);
4155 static inline bool __skb_ext_exist(const struct skb_ext
*ext
, enum skb_ext_id i
)
4157 return !!ext
->offset
[i
];
4160 static inline bool skb_ext_exist(const struct sk_buff
*skb
, enum skb_ext_id id
)
4162 return skb
->active_extensions
& (1 << id
);
4165 static inline void skb_ext_del(struct sk_buff
*skb
, enum skb_ext_id id
)
4167 if (skb_ext_exist(skb
, id
))
4168 __skb_ext_del(skb
, id
);
4171 static inline void *skb_ext_find(const struct sk_buff
*skb
, enum skb_ext_id id
)
4173 if (skb_ext_exist(skb
, id
)) {
4174 struct skb_ext
*ext
= skb
->extensions
;
4176 return (void *)ext
+ (ext
->offset
[id
] << 3);
4182 static inline void skb_ext_reset(struct sk_buff
*skb
)
4184 if (unlikely(skb
->active_extensions
)) {
4185 __skb_ext_put(skb
->extensions
);
4186 skb
->active_extensions
= 0;
4190 static inline bool skb_has_extensions(struct sk_buff
*skb
)
4192 return unlikely(skb
->active_extensions
);
4195 static inline void skb_ext_put(struct sk_buff
*skb
) {}
4196 static inline void skb_ext_reset(struct sk_buff
*skb
) {}
4197 static inline void skb_ext_del(struct sk_buff
*skb
, int unused
) {}
4198 static inline void __skb_ext_copy(struct sk_buff
*d
, const struct sk_buff
*s
) {}
4199 static inline void skb_ext_copy(struct sk_buff
*dst
, const struct sk_buff
*s
) {}
4200 static inline bool skb_has_extensions(struct sk_buff
*skb
) { return false; }
4201 #endif /* CONFIG_SKB_EXTENSIONS */
4203 static inline void nf_reset_ct(struct sk_buff
*skb
)
4205 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
4206 nf_conntrack_put(skb_nfct(skb
));
4211 static inline void nf_reset_trace(struct sk_buff
*skb
)
4213 #if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE) || defined(CONFIG_NF_TABLES)
4218 static inline void ipvs_reset(struct sk_buff
*skb
)
4220 #if IS_ENABLED(CONFIG_IP_VS)
4221 skb
->ipvs_property
= 0;
4225 /* Note: This doesn't put any conntrack info in dst. */
4226 static inline void __nf_copy(struct sk_buff
*dst
, const struct sk_buff
*src
,
4229 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
4230 dst
->_nfct
= src
->_nfct
;
4231 nf_conntrack_get(skb_nfct(src
));
4233 #if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE) || defined(CONFIG_NF_TABLES)
4235 dst
->nf_trace
= src
->nf_trace
;
4239 static inline void nf_copy(struct sk_buff
*dst
, const struct sk_buff
*src
)
4241 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
4242 nf_conntrack_put(skb_nfct(dst
));
4244 __nf_copy(dst
, src
, true);
4247 #ifdef CONFIG_NETWORK_SECMARK
4248 static inline void skb_copy_secmark(struct sk_buff
*to
, const struct sk_buff
*from
)
4250 to
->secmark
= from
->secmark
;
4253 static inline void skb_init_secmark(struct sk_buff
*skb
)
4258 static inline void skb_copy_secmark(struct sk_buff
*to
, const struct sk_buff
*from
)
4261 static inline void skb_init_secmark(struct sk_buff
*skb
)
4265 static inline int secpath_exists(const struct sk_buff
*skb
)
4268 return skb_ext_exist(skb
, SKB_EXT_SEC_PATH
);
4274 static inline bool skb_irq_freeable(const struct sk_buff
*skb
)
4276 return !skb
->destructor
&&
4277 !secpath_exists(skb
) &&
4279 !skb
->_skb_refdst
&&
4280 !skb_has_frag_list(skb
);
4283 static inline void skb_set_queue_mapping(struct sk_buff
*skb
, u16 queue_mapping
)
4285 skb
->queue_mapping
= queue_mapping
;
4288 static inline u16
skb_get_queue_mapping(const struct sk_buff
*skb
)
4290 return skb
->queue_mapping
;
4293 static inline void skb_copy_queue_mapping(struct sk_buff
*to
, const struct sk_buff
*from
)
4295 to
->queue_mapping
= from
->queue_mapping
;
4298 static inline void skb_record_rx_queue(struct sk_buff
*skb
, u16 rx_queue
)
4300 skb
->queue_mapping
= rx_queue
+ 1;
4303 static inline u16
skb_get_rx_queue(const struct sk_buff
*skb
)
4305 return skb
->queue_mapping
- 1;
4308 static inline bool skb_rx_queue_recorded(const struct sk_buff
*skb
)
4310 return skb
->queue_mapping
!= 0;
4313 static inline void skb_set_dst_pending_confirm(struct sk_buff
*skb
, u32 val
)
4315 skb
->dst_pending_confirm
= val
;
4318 static inline bool skb_get_dst_pending_confirm(const struct sk_buff
*skb
)
4320 return skb
->dst_pending_confirm
!= 0;
4323 static inline struct sec_path
*skb_sec_path(const struct sk_buff
*skb
)
4326 return skb_ext_find(skb
, SKB_EXT_SEC_PATH
);
4332 /* Keeps track of mac header offset relative to skb->head.
4333 * It is useful for TSO of Tunneling protocol. e.g. GRE.
4334 * For non-tunnel skb it points to skb_mac_header() and for
4335 * tunnel skb it points to outer mac header.
4336 * Keeps track of level of encapsulation of network headers.
4347 #define SKB_SGO_CB_OFFSET 32
4348 #define SKB_GSO_CB(skb) ((struct skb_gso_cb *)((skb)->cb + SKB_SGO_CB_OFFSET))
4350 static inline int skb_tnl_header_len(const struct sk_buff
*inner_skb
)
4352 return (skb_mac_header(inner_skb
) - inner_skb
->head
) -
4353 SKB_GSO_CB(inner_skb
)->mac_offset
;
4356 static inline int gso_pskb_expand_head(struct sk_buff
*skb
, int extra
)
4358 int new_headroom
, headroom
;
4361 headroom
= skb_headroom(skb
);
4362 ret
= pskb_expand_head(skb
, extra
, 0, GFP_ATOMIC
);
4366 new_headroom
= skb_headroom(skb
);
4367 SKB_GSO_CB(skb
)->mac_offset
+= (new_headroom
- headroom
);
4371 static inline void gso_reset_checksum(struct sk_buff
*skb
, __wsum res
)
4373 /* Do not update partial checksums if remote checksum is enabled. */
4374 if (skb
->remcsum_offload
)
4377 SKB_GSO_CB(skb
)->csum
= res
;
4378 SKB_GSO_CB(skb
)->csum_start
= skb_checksum_start(skb
) - skb
->head
;
4381 /* Compute the checksum for a gso segment. First compute the checksum value
4382 * from the start of transport header to SKB_GSO_CB(skb)->csum_start, and
4383 * then add in skb->csum (checksum from csum_start to end of packet).
4384 * skb->csum and csum_start are then updated to reflect the checksum of the
4385 * resultant packet starting from the transport header-- the resultant checksum
4386 * is in the res argument (i.e. normally zero or ~ of checksum of a pseudo
4389 static inline __sum16
gso_make_checksum(struct sk_buff
*skb
, __wsum res
)
4391 unsigned char *csum_start
= skb_transport_header(skb
);
4392 int plen
= (skb
->head
+ SKB_GSO_CB(skb
)->csum_start
) - csum_start
;
4393 __wsum partial
= SKB_GSO_CB(skb
)->csum
;
4395 SKB_GSO_CB(skb
)->csum
= res
;
4396 SKB_GSO_CB(skb
)->csum_start
= csum_start
- skb
->head
;
4398 return csum_fold(csum_partial(csum_start
, plen
, partial
));
4401 static inline bool skb_is_gso(const struct sk_buff
*skb
)
4403 return skb_shinfo(skb
)->gso_size
;
4406 /* Note: Should be called only if skb_is_gso(skb) is true */
4407 static inline bool skb_is_gso_v6(const struct sk_buff
*skb
)
4409 return skb_shinfo(skb
)->gso_type
& SKB_GSO_TCPV6
;
4412 /* Note: Should be called only if skb_is_gso(skb) is true */
4413 static inline bool skb_is_gso_sctp(const struct sk_buff
*skb
)
4415 return skb_shinfo(skb
)->gso_type
& SKB_GSO_SCTP
;
4418 /* Note: Should be called only if skb_is_gso(skb) is true */
4419 static inline bool skb_is_gso_tcp(const struct sk_buff
*skb
)
4421 return skb_shinfo(skb
)->gso_type
& (SKB_GSO_TCPV4
| SKB_GSO_TCPV6
);
4424 static inline void skb_gso_reset(struct sk_buff
*skb
)
4426 skb_shinfo(skb
)->gso_size
= 0;
4427 skb_shinfo(skb
)->gso_segs
= 0;
4428 skb_shinfo(skb
)->gso_type
= 0;
4431 static inline void skb_increase_gso_size(struct skb_shared_info
*shinfo
,
4434 if (WARN_ON_ONCE(shinfo
->gso_size
== GSO_BY_FRAGS
))
4436 shinfo
->gso_size
+= increment
;
4439 static inline void skb_decrease_gso_size(struct skb_shared_info
*shinfo
,
4442 if (WARN_ON_ONCE(shinfo
->gso_size
== GSO_BY_FRAGS
))
4444 shinfo
->gso_size
-= decrement
;
4447 void __skb_warn_lro_forwarding(const struct sk_buff
*skb
);
4449 static inline bool skb_warn_if_lro(const struct sk_buff
*skb
)
4451 /* LRO sets gso_size but not gso_type, whereas if GSO is really
4452 * wanted then gso_type will be set. */
4453 const struct skb_shared_info
*shinfo
= skb_shinfo(skb
);
4455 if (skb_is_nonlinear(skb
) && shinfo
->gso_size
!= 0 &&
4456 unlikely(shinfo
->gso_type
== 0)) {
4457 __skb_warn_lro_forwarding(skb
);
4463 static inline void skb_forward_csum(struct sk_buff
*skb
)
4465 /* Unfortunately we don't support this one. Any brave souls? */
4466 if (skb
->ip_summed
== CHECKSUM_COMPLETE
)
4467 skb
->ip_summed
= CHECKSUM_NONE
;
4471 * skb_checksum_none_assert - make sure skb ip_summed is CHECKSUM_NONE
4472 * @skb: skb to check
4474 * fresh skbs have their ip_summed set to CHECKSUM_NONE.
4475 * Instead of forcing ip_summed to CHECKSUM_NONE, we can
4476 * use this helper, to document places where we make this assertion.
4478 static inline void skb_checksum_none_assert(const struct sk_buff
*skb
)
4481 BUG_ON(skb
->ip_summed
!= CHECKSUM_NONE
);
4485 bool skb_partial_csum_set(struct sk_buff
*skb
, u16 start
, u16 off
);
4487 int skb_checksum_setup(struct sk_buff
*skb
, bool recalculate
);
4488 struct sk_buff
*skb_checksum_trimmed(struct sk_buff
*skb
,
4489 unsigned int transport_len
,
4490 __sum16(*skb_chkf
)(struct sk_buff
*skb
));
4493 * skb_head_is_locked - Determine if the skb->head is locked down
4494 * @skb: skb to check
4496 * The head on skbs build around a head frag can be removed if they are
4497 * not cloned. This function returns true if the skb head is locked down
4498 * due to either being allocated via kmalloc, or by being a clone with
4499 * multiple references to the head.
4501 static inline bool skb_head_is_locked(const struct sk_buff
*skb
)
4503 return !skb
->head_frag
|| skb_cloned(skb
);
4506 /* Local Checksum Offload.
4507 * Compute outer checksum based on the assumption that the
4508 * inner checksum will be offloaded later.
4509 * See Documentation/networking/checksum-offloads.rst for
4510 * explanation of how this works.
4511 * Fill in outer checksum adjustment (e.g. with sum of outer
4512 * pseudo-header) before calling.
4513 * Also ensure that inner checksum is in linear data area.
4515 static inline __wsum
lco_csum(struct sk_buff
*skb
)
4517 unsigned char *csum_start
= skb_checksum_start(skb
);
4518 unsigned char *l4_hdr
= skb_transport_header(skb
);
4521 /* Start with complement of inner checksum adjustment */
4522 partial
= ~csum_unfold(*(__force __sum16
*)(csum_start
+
4525 /* Add in checksum of our headers (incl. outer checksum
4526 * adjustment filled in by caller) and return result.
4528 return csum_partial(l4_hdr
, csum_start
- l4_hdr
, partial
);
4531 #endif /* __KERNEL__ */
4532 #endif /* _LINUX_SKBUFF_H */