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 #include <net/page_pool.h>
41 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
42 #include <linux/netfilter/nf_conntrack_common.h>
45 /* The interface for checksum offload between the stack and networking drivers
48 * A. IP checksum related features
50 * Drivers advertise checksum offload capabilities in the features of a device.
51 * From the stack's point of view these are capabilities offered by the driver.
52 * A driver typically only advertises features that it is capable of offloading
55 * The checksum related features are:
57 * NETIF_F_HW_CSUM - The driver (or its device) is able to compute one
58 * IP (one's complement) checksum for any combination
59 * of protocols or protocol layering. The checksum is
60 * computed and set in a packet per the CHECKSUM_PARTIAL
61 * interface (see below).
63 * NETIF_F_IP_CSUM - Driver (device) is only able to checksum plain
64 * TCP or UDP packets over IPv4. These are specifically
65 * unencapsulated packets of the form IPv4|TCP or
66 * IPv4|UDP where the Protocol field in the IPv4 header
67 * is TCP or UDP. The IPv4 header may contain IP options.
68 * This feature cannot be set in features for a device
69 * with NETIF_F_HW_CSUM also set. This feature is being
70 * DEPRECATED (see below).
72 * NETIF_F_IPV6_CSUM - Driver (device) is only able to checksum plain
73 * TCP or UDP packets over IPv6. These are specifically
74 * unencapsulated packets of the form IPv6|TCP or
75 * IPv6|UDP where the Next Header field in the IPv6
76 * header is either TCP or UDP. IPv6 extension headers
77 * are not supported with this feature. This feature
78 * cannot be set in features for a device with
79 * NETIF_F_HW_CSUM also set. This feature is being
80 * DEPRECATED (see below).
82 * NETIF_F_RXCSUM - Driver (device) performs receive checksum offload.
83 * This flag is only used to disable the RX checksum
84 * feature for a device. The stack will accept receive
85 * checksum indication in packets received on a device
86 * regardless of whether NETIF_F_RXCSUM is set.
88 * B. Checksumming of received packets by device. Indication of checksum
89 * verification is set in skb->ip_summed. Possible values are:
93 * Device did not checksum this packet e.g. due to lack of capabilities.
94 * The packet contains full (though not verified) checksum in packet but
95 * not in skb->csum. Thus, skb->csum is undefined in this case.
97 * CHECKSUM_UNNECESSARY:
99 * The hardware you're dealing with doesn't calculate the full checksum
100 * (as in CHECKSUM_COMPLETE), but it does parse headers and verify checksums
101 * for specific protocols. For such packets it will set CHECKSUM_UNNECESSARY
102 * if their checksums are okay. skb->csum is still undefined in this case
103 * though. A driver or device must never modify the checksum field in the
104 * packet even if checksum is verified.
106 * CHECKSUM_UNNECESSARY is applicable to following protocols:
107 * TCP: IPv6 and IPv4.
108 * UDP: IPv4 and IPv6. A device may apply CHECKSUM_UNNECESSARY to a
109 * zero UDP checksum for either IPv4 or IPv6, the networking stack
110 * may perform further validation in this case.
111 * GRE: only if the checksum is present in the header.
112 * SCTP: indicates the CRC in SCTP header has been validated.
113 * FCOE: indicates the CRC in FC frame has been validated.
115 * skb->csum_level indicates the number of consecutive checksums found in
116 * the packet minus one that have been verified as CHECKSUM_UNNECESSARY.
117 * For instance if a device receives an IPv6->UDP->GRE->IPv4->TCP packet
118 * and a device is able to verify the checksums for UDP (possibly zero),
119 * GRE (checksum flag is set) and TCP, skb->csum_level would be set to
120 * two. If the device were only able to verify the UDP checksum and not
121 * GRE, either because it doesn't support GRE checksum or because GRE
122 * checksum is bad, skb->csum_level would be set to zero (TCP checksum is
123 * not considered in this case).
127 * This is the most generic way. The device supplied checksum of the _whole_
128 * packet as seen by netif_rx() and fills in skb->csum. This means the
129 * hardware doesn't need to parse L3/L4 headers to implement this.
132 * - Even if device supports only some protocols, but is able to produce
133 * skb->csum, it MUST use CHECKSUM_COMPLETE, not CHECKSUM_UNNECESSARY.
134 * - CHECKSUM_COMPLETE is not applicable to SCTP and FCoE protocols.
138 * A checksum is set up to be offloaded to a device as described in the
139 * output description for CHECKSUM_PARTIAL. This may occur on a packet
140 * received directly from another Linux OS, e.g., a virtualized Linux kernel
141 * on the same host, or it may be set in the input path in GRO or remote
142 * checksum offload. For the purposes of checksum verification, the checksum
143 * referred to by skb->csum_start + skb->csum_offset and any preceding
144 * checksums in the packet are considered verified. Any checksums in the
145 * packet that are after the checksum being offloaded are not considered to
148 * C. Checksumming on transmit for non-GSO. The stack requests checksum offload
149 * in the skb->ip_summed for a packet. Values are:
153 * The driver is required to checksum the packet as seen by hard_start_xmit()
154 * from skb->csum_start up to the end, and to record/write the checksum at
155 * offset skb->csum_start + skb->csum_offset. A driver may verify that the
156 * csum_start and csum_offset values are valid values given the length and
157 * offset of the packet, but it should not attempt to validate that the
158 * checksum refers to a legitimate transport layer checksum -- it is the
159 * purview of the stack to validate that csum_start and csum_offset are set
162 * When the stack requests checksum offload for a packet, the driver MUST
163 * ensure that the checksum is set correctly. A driver can either offload the
164 * checksum calculation to the device, or call skb_checksum_help (in the case
165 * that the device does not support offload for a particular checksum).
167 * NETIF_F_IP_CSUM and NETIF_F_IPV6_CSUM are being deprecated in favor of
168 * NETIF_F_HW_CSUM. New devices should use NETIF_F_HW_CSUM to indicate
169 * checksum offload capability.
170 * skb_csum_hwoffload_help() can be called to resolve CHECKSUM_PARTIAL based
171 * on network device checksumming capabilities: if a packet does not match
172 * them, skb_checksum_help or skb_crc32c_help (depending on the value of
173 * csum_not_inet, see item D.) is called to resolve the checksum.
177 * The skb was already checksummed by the protocol, or a checksum is not
180 * CHECKSUM_UNNECESSARY:
182 * This has the same meaning as CHECKSUM_NONE for checksum offload on
186 * Not used in checksum output. If a driver observes a packet with this value
187 * set in skbuff, it should treat the packet as if CHECKSUM_NONE were set.
189 * D. Non-IP checksum (CRC) offloads
191 * NETIF_F_SCTP_CRC - This feature indicates that a device is capable of
192 * offloading the SCTP CRC in a packet. To perform this offload the stack
193 * will set csum_start and csum_offset accordingly, set ip_summed to
194 * CHECKSUM_PARTIAL and set csum_not_inet to 1, to provide an indication in
195 * the skbuff that the CHECKSUM_PARTIAL refers to CRC32c.
196 * A driver that supports both IP checksum offload and SCTP CRC32c offload
197 * must verify which offload is configured for a packet by testing the
198 * value of skb->csum_not_inet; skb_crc32c_csum_help is provided to resolve
199 * CHECKSUM_PARTIAL on skbs where csum_not_inet is set to 1.
201 * NETIF_F_FCOE_CRC - This feature indicates that a device is capable of
202 * offloading the FCOE CRC in a packet. To perform this offload the stack
203 * will set ip_summed to CHECKSUM_PARTIAL and set csum_start and csum_offset
204 * accordingly. Note that there is no indication in the skbuff that the
205 * CHECKSUM_PARTIAL refers to an FCOE checksum, so a driver that supports
206 * both IP checksum offload and FCOE CRC offload must verify which offload
207 * is configured for a packet, presumably by inspecting packet headers.
209 * E. Checksumming on output with GSO.
211 * In the case of a GSO packet (skb_is_gso(skb) is true), checksum offload
212 * is implied by the SKB_GSO_* flags in gso_type. Most obviously, if the
213 * gso_type is SKB_GSO_TCPV4 or SKB_GSO_TCPV6, TCP checksum offload as
214 * part of the GSO operation is implied. If a checksum is being offloaded
215 * with GSO then ip_summed is CHECKSUM_PARTIAL, and both csum_start and
216 * csum_offset are set to refer to the outermost checksum being offloaded
217 * (two offloaded checksums are possible with UDP encapsulation).
220 /* Don't change this without changing skb_csum_unnecessary! */
221 #define CHECKSUM_NONE 0
222 #define CHECKSUM_UNNECESSARY 1
223 #define CHECKSUM_COMPLETE 2
224 #define CHECKSUM_PARTIAL 3
226 /* Maximum value in skb->csum_level */
227 #define SKB_MAX_CSUM_LEVEL 3
229 #define SKB_DATA_ALIGN(X) ALIGN(X, SMP_CACHE_BYTES)
230 #define SKB_WITH_OVERHEAD(X) \
231 ((X) - SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
232 #define SKB_MAX_ORDER(X, ORDER) \
233 SKB_WITH_OVERHEAD((PAGE_SIZE << (ORDER)) - (X))
234 #define SKB_MAX_HEAD(X) (SKB_MAX_ORDER((X), 0))
235 #define SKB_MAX_ALLOC (SKB_MAX_ORDER(0, 2))
237 /* return minimum truesize of one skb containing X bytes of data */
238 #define SKB_TRUESIZE(X) ((X) + \
239 SKB_DATA_ALIGN(sizeof(struct sk_buff)) + \
240 SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
242 struct ahash_request
;
245 struct pipe_inode_info
;
252 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
253 struct nf_bridge_info
{
255 BRNF_PROTO_UNCHANGED
,
263 struct net_device
*physindev
;
265 /* always valid & non-NULL from FORWARD on, for physdev match */
266 struct net_device
*physoutdev
;
268 /* prerouting: detect dnat in orig/reply direction */
270 struct in6_addr ipv6_daddr
;
272 /* after prerouting + nat detected: store original source
273 * mac since neigh resolution overwrites it, only used while
274 * skb is out in neigh layer.
276 char neigh_header
[8];
281 #if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
282 /* Chain in tc_skb_ext will be used to share the tc chain with
283 * ovs recirc_id. It will be set to the current chain by tc
284 * and read by ovs to recirc_id.
293 struct sk_buff_head
{
294 /* These two members must be first. */
295 struct sk_buff
*next
;
296 struct sk_buff
*prev
;
304 /* To allow 64K frame to be packed as single skb without frag_list we
305 * require 64K/PAGE_SIZE pages plus 1 additional page to allow for
306 * buffers which do not start on a page boundary.
308 * Since GRO uses frags we allocate at least 16 regardless of page
311 #if (65536/PAGE_SIZE + 1) < 16
312 #define MAX_SKB_FRAGS 16UL
314 #define MAX_SKB_FRAGS (65536/PAGE_SIZE + 1)
316 extern int sysctl_max_skb_frags
;
318 /* Set skb_shinfo(skb)->gso_size to this in case you want skb_segment to
319 * segment using its current segmentation instead.
321 #define GSO_BY_FRAGS 0xFFFF
323 typedef struct bio_vec skb_frag_t
;
326 * skb_frag_size() - Returns the size of a skb fragment
327 * @frag: skb fragment
329 static inline unsigned int skb_frag_size(const skb_frag_t
*frag
)
335 * skb_frag_size_set() - Sets the size of a skb fragment
336 * @frag: skb fragment
337 * @size: size of fragment
339 static inline void skb_frag_size_set(skb_frag_t
*frag
, unsigned int size
)
345 * skb_frag_size_add() - Increments the size of a skb fragment by @delta
346 * @frag: skb fragment
347 * @delta: value to add
349 static inline void skb_frag_size_add(skb_frag_t
*frag
, int delta
)
351 frag
->bv_len
+= delta
;
355 * skb_frag_size_sub() - Decrements the size of a skb fragment by @delta
356 * @frag: skb fragment
357 * @delta: value to subtract
359 static inline void skb_frag_size_sub(skb_frag_t
*frag
, int delta
)
361 frag
->bv_len
-= delta
;
365 * skb_frag_must_loop - Test if %p is a high memory page
366 * @p: fragment's page
368 static inline bool skb_frag_must_loop(struct page
*p
)
370 #if defined(CONFIG_HIGHMEM)
371 if (IS_ENABLED(CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP
) || PageHighMem(p
))
378 * skb_frag_foreach_page - loop over pages in a fragment
380 * @f: skb frag to operate on
381 * @f_off: offset from start of f->bv_page
382 * @f_len: length from f_off to loop over
383 * @p: (temp var) current page
384 * @p_off: (temp var) offset from start of current page,
385 * non-zero only on first page.
386 * @p_len: (temp var) length in current page,
387 * < PAGE_SIZE only on first and last page.
388 * @copied: (temp var) length so far, excluding current p_len.
390 * A fragment can hold a compound page, in which case per-page
391 * operations, notably kmap_atomic, must be called for each
394 #define skb_frag_foreach_page(f, f_off, f_len, p, p_off, p_len, copied) \
395 for (p = skb_frag_page(f) + ((f_off) >> PAGE_SHIFT), \
396 p_off = (f_off) & (PAGE_SIZE - 1), \
397 p_len = skb_frag_must_loop(p) ? \
398 min_t(u32, f_len, PAGE_SIZE - p_off) : f_len, \
401 copied += p_len, p++, p_off = 0, \
402 p_len = min_t(u32, f_len - copied, PAGE_SIZE)) \
404 #define HAVE_HW_TIME_STAMP
407 * struct skb_shared_hwtstamps - hardware time stamps
408 * @hwtstamp: hardware time stamp transformed into duration
409 * since arbitrary point in time
411 * Software time stamps generated by ktime_get_real() are stored in
414 * hwtstamps can only be compared against other hwtstamps from
417 * This structure is attached to packets as part of the
418 * &skb_shared_info. Use skb_hwtstamps() to get a pointer.
420 struct skb_shared_hwtstamps
{
424 /* Definitions for tx_flags in struct skb_shared_info */
426 /* generate hardware time stamp */
427 SKBTX_HW_TSTAMP
= 1 << 0,
429 /* generate software time stamp when queueing packet to NIC */
430 SKBTX_SW_TSTAMP
= 1 << 1,
432 /* device driver is going to provide hardware time stamp */
433 SKBTX_IN_PROGRESS
= 1 << 2,
435 /* generate wifi status information (where possible) */
436 SKBTX_WIFI_STATUS
= 1 << 4,
438 /* generate software time stamp when entering packet scheduling */
439 SKBTX_SCHED_TSTAMP
= 1 << 6,
442 #define SKBTX_ANY_SW_TSTAMP (SKBTX_SW_TSTAMP | \
444 #define SKBTX_ANY_TSTAMP (SKBTX_HW_TSTAMP | SKBTX_ANY_SW_TSTAMP)
446 /* Definitions for flags in struct skb_shared_info */
448 /* use zcopy routines */
449 SKBFL_ZEROCOPY_ENABLE
= BIT(0),
451 /* This indicates at least one fragment might be overwritten
452 * (as in vmsplice(), sendfile() ...)
453 * If we need to compute a TX checksum, we'll need to copy
454 * all frags to avoid possible bad checksum
456 SKBFL_SHARED_FRAG
= BIT(1),
459 #define SKBFL_ZEROCOPY_FRAG (SKBFL_ZEROCOPY_ENABLE | SKBFL_SHARED_FRAG)
462 * The callback notifies userspace to release buffers when skb DMA is done in
463 * lower device, the skb last reference should be 0 when calling this.
464 * The zerocopy_success argument is true if zero copy transmit occurred,
465 * false on data copy or out of memory error caused by data copy attempt.
466 * The ctx field is used to track device context.
467 * The desc field is used to track userspace buffer index.
470 void (*callback
)(struct sk_buff
*, struct ubuf_info
*,
471 bool zerocopy_success
);
488 struct user_struct
*user
;
493 #define skb_uarg(SKB) ((struct ubuf_info *)(skb_shinfo(SKB)->destructor_arg))
495 int mm_account_pinned_pages(struct mmpin
*mmp
, size_t size
);
496 void mm_unaccount_pinned_pages(struct mmpin
*mmp
);
498 struct ubuf_info
*msg_zerocopy_alloc(struct sock
*sk
, size_t size
);
499 struct ubuf_info
*msg_zerocopy_realloc(struct sock
*sk
, size_t size
,
500 struct ubuf_info
*uarg
);
502 void msg_zerocopy_put_abort(struct ubuf_info
*uarg
, bool have_uref
);
504 void msg_zerocopy_callback(struct sk_buff
*skb
, struct ubuf_info
*uarg
,
507 int skb_zerocopy_iter_dgram(struct sk_buff
*skb
, struct msghdr
*msg
, int len
);
508 int skb_zerocopy_iter_stream(struct sock
*sk
, struct sk_buff
*skb
,
509 struct msghdr
*msg
, int len
,
510 struct ubuf_info
*uarg
);
512 /* This data is invariant across clones and lives at
513 * the end of the header data, ie. at skb->end.
515 struct skb_shared_info
{
520 unsigned short gso_size
;
521 /* Warning: this field is not always filled in (UFO)! */
522 unsigned short gso_segs
;
523 struct sk_buff
*frag_list
;
524 struct skb_shared_hwtstamps hwtstamps
;
525 unsigned int gso_type
;
529 * Warning : all fields before dataref are cleared in __alloc_skb()
533 /* Intermediate layers must ensure that destructor_arg
534 * remains valid until skb destructor */
535 void * destructor_arg
;
537 /* must be last field, see pskb_expand_head() */
538 skb_frag_t frags
[MAX_SKB_FRAGS
];
541 /* We divide dataref into two halves. The higher 16 bits hold references
542 * to the payload part of skb->data. The lower 16 bits hold references to
543 * the entire skb->data. A clone of a headerless skb holds the length of
544 * the header in skb->hdr_len.
546 * All users must obey the rule that the skb->data reference count must be
547 * greater than or equal to the payload reference count.
549 * Holding a reference to the payload part means that the user does not
550 * care about modifications to the header part of skb->data.
552 #define SKB_DATAREF_SHIFT 16
553 #define SKB_DATAREF_MASK ((1 << SKB_DATAREF_SHIFT) - 1)
557 SKB_FCLONE_UNAVAILABLE
, /* skb has no fclone (from head_cache) */
558 SKB_FCLONE_ORIG
, /* orig skb (from fclone_cache) */
559 SKB_FCLONE_CLONE
, /* companion fclone skb (from fclone_cache) */
563 SKB_GSO_TCPV4
= 1 << 0,
565 /* This indicates the skb is from an untrusted source. */
566 SKB_GSO_DODGY
= 1 << 1,
568 /* This indicates the tcp segment has CWR set. */
569 SKB_GSO_TCP_ECN
= 1 << 2,
571 SKB_GSO_TCP_FIXEDID
= 1 << 3,
573 SKB_GSO_TCPV6
= 1 << 4,
575 SKB_GSO_FCOE
= 1 << 5,
577 SKB_GSO_GRE
= 1 << 6,
579 SKB_GSO_GRE_CSUM
= 1 << 7,
581 SKB_GSO_IPXIP4
= 1 << 8,
583 SKB_GSO_IPXIP6
= 1 << 9,
585 SKB_GSO_UDP_TUNNEL
= 1 << 10,
587 SKB_GSO_UDP_TUNNEL_CSUM
= 1 << 11,
589 SKB_GSO_PARTIAL
= 1 << 12,
591 SKB_GSO_TUNNEL_REMCSUM
= 1 << 13,
593 SKB_GSO_SCTP
= 1 << 14,
595 SKB_GSO_ESP
= 1 << 15,
597 SKB_GSO_UDP
= 1 << 16,
599 SKB_GSO_UDP_L4
= 1 << 17,
601 SKB_GSO_FRAGLIST
= 1 << 18,
604 #if BITS_PER_LONG > 32
605 #define NET_SKBUFF_DATA_USES_OFFSET 1
608 #ifdef NET_SKBUFF_DATA_USES_OFFSET
609 typedef unsigned int sk_buff_data_t
;
611 typedef unsigned char *sk_buff_data_t
;
615 * struct sk_buff - socket buffer
616 * @next: Next buffer in list
617 * @prev: Previous buffer in list
618 * @tstamp: Time we arrived/left
619 * @skb_mstamp_ns: (aka @tstamp) earliest departure time; start point
620 * for retransmit timer
621 * @rbnode: RB tree node, alternative to next/prev for netem/tcp
623 * @sk: Socket we are owned by
624 * @ip_defrag_offset: (aka @sk) alternate use of @sk, used in
625 * fragmentation management
626 * @dev: Device we arrived on/are leaving by
627 * @dev_scratch: (aka @dev) alternate use of @dev when @dev would be %NULL
628 * @cb: Control buffer. Free for use by every layer. Put private vars here
629 * @_skb_refdst: destination entry (with norefcount bit)
630 * @sp: the security path, used for xfrm
631 * @len: Length of actual data
632 * @data_len: Data length
633 * @mac_len: Length of link layer header
634 * @hdr_len: writable header length of cloned skb
635 * @csum: Checksum (must include start/offset pair)
636 * @csum_start: Offset from skb->head where checksumming should start
637 * @csum_offset: Offset from csum_start where checksum should be stored
638 * @priority: Packet queueing priority
639 * @ignore_df: allow local fragmentation
640 * @cloned: Head may be cloned (check refcnt to be sure)
641 * @ip_summed: Driver fed us an IP checksum
642 * @nohdr: Payload reference only, must not modify header
643 * @pkt_type: Packet class
644 * @fclone: skbuff clone status
645 * @ipvs_property: skbuff is owned by ipvs
646 * @inner_protocol_type: whether the inner protocol is
647 * ENCAP_TYPE_ETHER or ENCAP_TYPE_IPPROTO
648 * @remcsum_offload: remote checksum offload is enabled
649 * @offload_fwd_mark: Packet was L2-forwarded in hardware
650 * @offload_l3_fwd_mark: Packet was L3-forwarded in hardware
651 * @tc_skip_classify: do not classify packet. set by IFB device
652 * @tc_at_ingress: used within tc_classify to distinguish in/egress
653 * @redirected: packet was redirected by packet classifier
654 * @from_ingress: packet was redirected from the ingress path
655 * @peeked: this packet has been seen already, so stats have been
656 * done for it, don't do them again
657 * @nf_trace: netfilter packet trace flag
658 * @protocol: Packet protocol from driver
659 * @destructor: Destruct function
660 * @tcp_tsorted_anchor: list structure for TCP (tp->tsorted_sent_queue)
661 * @_sk_redir: socket redirection information for skmsg
662 * @_nfct: Associated connection, if any (with nfctinfo bits)
663 * @nf_bridge: Saved data about a bridged frame - see br_netfilter.c
664 * @skb_iif: ifindex of device we arrived on
665 * @tc_index: Traffic control index
666 * @hash: the packet hash
667 * @queue_mapping: Queue mapping for multiqueue devices
668 * @head_frag: skb was allocated from page fragments,
669 * not allocated by kmalloc() or vmalloc().
670 * @pfmemalloc: skbuff was allocated from PFMEMALLOC reserves
671 * @pp_recycle: mark the packet for recycling instead of freeing (implies
672 * page_pool support on driver)
673 * @active_extensions: active extensions (skb_ext_id types)
674 * @ndisc_nodetype: router type (from link layer)
675 * @ooo_okay: allow the mapping of a socket to a queue to be changed
676 * @l4_hash: indicate hash is a canonical 4-tuple hash over transport
678 * @sw_hash: indicates hash was computed in software stack
679 * @wifi_acked_valid: wifi_acked was set
680 * @wifi_acked: whether frame was acked on wifi or not
681 * @no_fcs: Request NIC to treat last 4 bytes as Ethernet FCS
682 * @encapsulation: indicates the inner headers in the skbuff are valid
683 * @encap_hdr_csum: software checksum is needed
684 * @csum_valid: checksum is already valid
685 * @csum_not_inet: use CRC32c to resolve CHECKSUM_PARTIAL
686 * @csum_complete_sw: checksum was completed by software
687 * @csum_level: indicates the number of consecutive checksums found in
688 * the packet minus one that have been verified as
689 * CHECKSUM_UNNECESSARY (max 3)
690 * @dst_pending_confirm: need to confirm neighbour
691 * @decrypted: Decrypted SKB
692 * @napi_id: id of the NAPI struct this skb came from
693 * @sender_cpu: (aka @napi_id) source CPU in XPS
694 * @secmark: security marking
695 * @mark: Generic packet mark
696 * @reserved_tailroom: (aka @mark) number of bytes of free space available
697 * at the tail of an sk_buff
698 * @vlan_present: VLAN tag is present
699 * @vlan_proto: vlan encapsulation protocol
700 * @vlan_tci: vlan tag control information
701 * @inner_protocol: Protocol (encapsulation)
702 * @inner_ipproto: (aka @inner_protocol) stores ipproto when
703 * skb->inner_protocol_type == ENCAP_TYPE_IPPROTO;
704 * @inner_transport_header: Inner transport layer header (encapsulation)
705 * @inner_network_header: Network layer header (encapsulation)
706 * @inner_mac_header: Link layer header (encapsulation)
707 * @transport_header: Transport layer header
708 * @network_header: Network layer header
709 * @mac_header: Link layer header
710 * @kcov_handle: KCOV remote handle for remote coverage collection
711 * @tail: Tail pointer
713 * @head: Head of buffer
714 * @data: Data head pointer
715 * @truesize: Buffer size
716 * @users: User count - see {datagram,tcp}.c
717 * @extensions: allocated extensions, valid if active_extensions is nonzero
723 /* These two members must be first. */
724 struct sk_buff
*next
;
725 struct sk_buff
*prev
;
728 struct net_device
*dev
;
729 /* Some protocols might use this space to store information,
730 * while device pointer would be NULL.
731 * UDP receive path is one user.
733 unsigned long dev_scratch
;
736 struct rb_node rbnode
; /* used in netem, ip4 defrag, and tcp stack */
737 struct list_head list
;
742 int ip_defrag_offset
;
747 u64 skb_mstamp_ns
; /* earliest departure time */
750 * This is the control buffer. It is free to use for every
751 * layer. Please put your private variables there. If you
752 * want to keep them across layers you have to do a skb_clone()
753 * first. This is owned by whoever has the skb queued ATM.
755 char cb
[48] __aligned(8);
759 unsigned long _skb_refdst
;
760 void (*destructor
)(struct sk_buff
*skb
);
762 struct list_head tcp_tsorted_anchor
;
763 #ifdef CONFIG_NET_SOCK_MSG
764 unsigned long _sk_redir
;
768 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
776 /* Following fields are _not_ copied in __copy_skb_header()
777 * Note that queue_mapping is here mostly to fill a hole.
781 /* if you move cloned around you also must adapt those constants */
782 #ifdef __BIG_ENDIAN_BITFIELD
783 #define CLONED_MASK (1 << 7)
785 #define CLONED_MASK 1
787 #define CLONED_OFFSET() offsetof(struct sk_buff, __cloned_offset)
790 __u8 __cloned_offset
[0];
798 pp_recycle
:1; /* page_pool recycle indicator */
799 #ifdef CONFIG_SKB_EXTENSIONS
800 __u8 active_extensions
;
803 /* fields enclosed in headers_start/headers_end are copied
804 * using a single memcpy() in __copy_skb_header()
807 __u32 headers_start
[0];
810 /* if you move pkt_type around you also must adapt those constants */
811 #ifdef __BIG_ENDIAN_BITFIELD
812 #define PKT_TYPE_MAX (7 << 5)
814 #define PKT_TYPE_MAX 7
816 #define PKT_TYPE_OFFSET() offsetof(struct sk_buff, __pkt_type_offset)
819 __u8 __pkt_type_offset
[0];
829 __u8 wifi_acked_valid
:1;
832 /* Indicates the inner headers are valid in the skbuff. */
833 __u8 encapsulation
:1;
834 __u8 encap_hdr_csum
:1;
837 #ifdef __BIG_ENDIAN_BITFIELD
838 #define PKT_VLAN_PRESENT_BIT 7
840 #define PKT_VLAN_PRESENT_BIT 0
842 #define PKT_VLAN_PRESENT_OFFSET() offsetof(struct sk_buff, __pkt_vlan_present_offset)
844 __u8 __pkt_vlan_present_offset
[0];
847 __u8 csum_complete_sw
:1;
849 __u8 csum_not_inet
:1;
850 __u8 dst_pending_confirm
:1;
851 #ifdef CONFIG_IPV6_NDISC_NODETYPE
852 __u8 ndisc_nodetype
:2;
855 __u8 ipvs_property
:1;
856 __u8 inner_protocol_type
:1;
857 __u8 remcsum_offload
:1;
858 #ifdef CONFIG_NET_SWITCHDEV
859 __u8 offload_fwd_mark
:1;
860 __u8 offload_l3_fwd_mark
:1;
862 #ifdef CONFIG_NET_CLS_ACT
863 __u8 tc_skip_classify
:1;
864 __u8 tc_at_ingress
:1;
866 #ifdef CONFIG_NET_REDIRECT
870 #ifdef CONFIG_TLS_DEVICE
874 #ifdef CONFIG_NET_SCHED
875 __u16 tc_index
; /* traffic control index */
890 #if defined(CONFIG_NET_RX_BUSY_POLL) || defined(CONFIG_XPS)
892 unsigned int napi_id
;
893 unsigned int sender_cpu
;
896 #ifdef CONFIG_NETWORK_SECMARK
902 __u32 reserved_tailroom
;
906 __be16 inner_protocol
;
910 __u16 inner_transport_header
;
911 __u16 inner_network_header
;
912 __u16 inner_mac_header
;
915 __u16 transport_header
;
916 __u16 network_header
;
924 __u32 headers_end
[0];
927 /* These elements must be at the end, see alloc_skb() for details. */
932 unsigned int truesize
;
935 #ifdef CONFIG_SKB_EXTENSIONS
936 /* only useable after checking ->active_extensions != 0 */
937 struct skb_ext
*extensions
;
943 * Handling routines are only of interest to the kernel
946 #define SKB_ALLOC_FCLONE 0x01
947 #define SKB_ALLOC_RX 0x02
948 #define SKB_ALLOC_NAPI 0x04
951 * skb_pfmemalloc - Test if the skb was allocated from PFMEMALLOC reserves
954 static inline bool skb_pfmemalloc(const struct sk_buff
*skb
)
956 return unlikely(skb
->pfmemalloc
);
960 * skb might have a dst pointer attached, refcounted or not.
961 * _skb_refdst low order bit is set if refcount was _not_ taken
963 #define SKB_DST_NOREF 1UL
964 #define SKB_DST_PTRMASK ~(SKB_DST_NOREF)
967 * skb_dst - returns skb dst_entry
970 * Returns skb dst_entry, regardless of reference taken or not.
972 static inline struct dst_entry
*skb_dst(const struct sk_buff
*skb
)
974 /* If refdst was not refcounted, check we still are in a
975 * rcu_read_lock section
977 WARN_ON((skb
->_skb_refdst
& SKB_DST_NOREF
) &&
978 !rcu_read_lock_held() &&
979 !rcu_read_lock_bh_held());
980 return (struct dst_entry
*)(skb
->_skb_refdst
& SKB_DST_PTRMASK
);
984 * skb_dst_set - sets skb dst
988 * Sets skb dst, assuming a reference was taken on dst and should
989 * be released by skb_dst_drop()
991 static inline void skb_dst_set(struct sk_buff
*skb
, struct dst_entry
*dst
)
993 skb
->_skb_refdst
= (unsigned long)dst
;
997 * skb_dst_set_noref - sets skb dst, hopefully, without taking reference
1001 * Sets skb dst, assuming a reference was not taken on dst.
1002 * If dst entry is cached, we do not take reference and dst_release
1003 * will be avoided by refdst_drop. If dst entry is not cached, we take
1004 * reference, so that last dst_release can destroy the dst immediately.
1006 static inline void skb_dst_set_noref(struct sk_buff
*skb
, struct dst_entry
*dst
)
1008 WARN_ON(!rcu_read_lock_held() && !rcu_read_lock_bh_held());
1009 skb
->_skb_refdst
= (unsigned long)dst
| SKB_DST_NOREF
;
1013 * skb_dst_is_noref - Test if skb dst isn't refcounted
1016 static inline bool skb_dst_is_noref(const struct sk_buff
*skb
)
1018 return (skb
->_skb_refdst
& SKB_DST_NOREF
) && skb_dst(skb
);
1022 * skb_rtable - Returns the skb &rtable
1025 static inline struct rtable
*skb_rtable(const struct sk_buff
*skb
)
1027 return (struct rtable
*)skb_dst(skb
);
1030 /* For mangling skb->pkt_type from user space side from applications
1031 * such as nft, tc, etc, we only allow a conservative subset of
1032 * possible pkt_types to be set.
1034 static inline bool skb_pkt_type_ok(u32 ptype
)
1036 return ptype
<= PACKET_OTHERHOST
;
1040 * skb_napi_id - Returns the skb's NAPI id
1043 static inline unsigned int skb_napi_id(const struct sk_buff
*skb
)
1045 #ifdef CONFIG_NET_RX_BUSY_POLL
1046 return skb
->napi_id
;
1053 * skb_unref - decrement the skb's reference count
1056 * Returns true if we can free the skb.
1058 static inline bool skb_unref(struct sk_buff
*skb
)
1062 if (likely(refcount_read(&skb
->users
) == 1))
1064 else if (likely(!refcount_dec_and_test(&skb
->users
)))
1070 void skb_release_head_state(struct sk_buff
*skb
);
1071 void kfree_skb(struct sk_buff
*skb
);
1072 void kfree_skb_list(struct sk_buff
*segs
);
1073 void skb_dump(const char *level
, const struct sk_buff
*skb
, bool full_pkt
);
1074 void skb_tx_error(struct sk_buff
*skb
);
1076 #ifdef CONFIG_TRACEPOINTS
1077 void consume_skb(struct sk_buff
*skb
);
1079 static inline void consume_skb(struct sk_buff
*skb
)
1081 return kfree_skb(skb
);
1085 void __consume_stateless_skb(struct sk_buff
*skb
);
1086 void __kfree_skb(struct sk_buff
*skb
);
1087 extern struct kmem_cache
*skbuff_head_cache
;
1089 void kfree_skb_partial(struct sk_buff
*skb
, bool head_stolen
);
1090 bool skb_try_coalesce(struct sk_buff
*to
, struct sk_buff
*from
,
1091 bool *fragstolen
, int *delta_truesize
);
1093 struct sk_buff
*__alloc_skb(unsigned int size
, gfp_t priority
, int flags
,
1095 struct sk_buff
*__build_skb(void *data
, unsigned int frag_size
);
1096 struct sk_buff
*build_skb(void *data
, unsigned int frag_size
);
1097 struct sk_buff
*build_skb_around(struct sk_buff
*skb
,
1098 void *data
, unsigned int frag_size
);
1100 struct sk_buff
*napi_build_skb(void *data
, unsigned int frag_size
);
1103 * alloc_skb - allocate a network buffer
1104 * @size: size to allocate
1105 * @priority: allocation mask
1107 * This function is a convenient wrapper around __alloc_skb().
1109 static inline struct sk_buff
*alloc_skb(unsigned int size
,
1112 return __alloc_skb(size
, priority
, 0, NUMA_NO_NODE
);
1115 struct sk_buff
*alloc_skb_with_frags(unsigned long header_len
,
1116 unsigned long data_len
,
1120 struct sk_buff
*alloc_skb_for_msg(struct sk_buff
*first
);
1122 /* Layout of fast clones : [skb1][skb2][fclone_ref] */
1123 struct sk_buff_fclones
{
1124 struct sk_buff skb1
;
1126 struct sk_buff skb2
;
1128 refcount_t fclone_ref
;
1132 * skb_fclone_busy - check if fclone is busy
1136 * Returns true if skb is a fast clone, and its clone is not freed.
1137 * Some drivers call skb_orphan() in their ndo_start_xmit(),
1138 * so we also check that this didnt happen.
1140 static inline bool skb_fclone_busy(const struct sock
*sk
,
1141 const struct sk_buff
*skb
)
1143 const struct sk_buff_fclones
*fclones
;
1145 fclones
= container_of(skb
, struct sk_buff_fclones
, skb1
);
1147 return skb
->fclone
== SKB_FCLONE_ORIG
&&
1148 refcount_read(&fclones
->fclone_ref
) > 1 &&
1149 READ_ONCE(fclones
->skb2
.sk
) == sk
;
1153 * alloc_skb_fclone - allocate a network buffer from fclone cache
1154 * @size: size to allocate
1155 * @priority: allocation mask
1157 * This function is a convenient wrapper around __alloc_skb().
1159 static inline struct sk_buff
*alloc_skb_fclone(unsigned int size
,
1162 return __alloc_skb(size
, priority
, SKB_ALLOC_FCLONE
, NUMA_NO_NODE
);
1165 struct sk_buff
*skb_morph(struct sk_buff
*dst
, struct sk_buff
*src
);
1166 void skb_headers_offset_update(struct sk_buff
*skb
, int off
);
1167 int skb_copy_ubufs(struct sk_buff
*skb
, gfp_t gfp_mask
);
1168 struct sk_buff
*skb_clone(struct sk_buff
*skb
, gfp_t priority
);
1169 void skb_copy_header(struct sk_buff
*new, const struct sk_buff
*old
);
1170 struct sk_buff
*skb_copy(const struct sk_buff
*skb
, gfp_t priority
);
1171 struct sk_buff
*__pskb_copy_fclone(struct sk_buff
*skb
, int headroom
,
1172 gfp_t gfp_mask
, bool fclone
);
1173 static inline struct sk_buff
*__pskb_copy(struct sk_buff
*skb
, int headroom
,
1176 return __pskb_copy_fclone(skb
, headroom
, gfp_mask
, false);
1179 int pskb_expand_head(struct sk_buff
*skb
, int nhead
, int ntail
, gfp_t gfp_mask
);
1180 struct sk_buff
*skb_realloc_headroom(struct sk_buff
*skb
,
1181 unsigned int headroom
);
1182 struct sk_buff
*skb_copy_expand(const struct sk_buff
*skb
, int newheadroom
,
1183 int newtailroom
, gfp_t priority
);
1184 int __must_check
skb_to_sgvec_nomark(struct sk_buff
*skb
, struct scatterlist
*sg
,
1185 int offset
, int len
);
1186 int __must_check
skb_to_sgvec(struct sk_buff
*skb
, struct scatterlist
*sg
,
1187 int offset
, int len
);
1188 int skb_cow_data(struct sk_buff
*skb
, int tailbits
, struct sk_buff
**trailer
);
1189 int __skb_pad(struct sk_buff
*skb
, int pad
, bool free_on_error
);
1192 * skb_pad - zero pad the tail of an skb
1193 * @skb: buffer to pad
1194 * @pad: space to pad
1196 * Ensure that a buffer is followed by a padding area that is zero
1197 * filled. Used by network drivers which may DMA or transfer data
1198 * beyond the buffer end onto the wire.
1200 * May return error in out of memory cases. The skb is freed on error.
1202 static inline int skb_pad(struct sk_buff
*skb
, int pad
)
1204 return __skb_pad(skb
, pad
, true);
1206 #define dev_kfree_skb(a) consume_skb(a)
1208 int skb_append_pagefrags(struct sk_buff
*skb
, struct page
*page
,
1209 int offset
, size_t size
);
1211 struct skb_seq_state
{
1215 __u32 stepped_offset
;
1216 struct sk_buff
*root_skb
;
1217 struct sk_buff
*cur_skb
;
1222 void skb_prepare_seq_read(struct sk_buff
*skb
, unsigned int from
,
1223 unsigned int to
, struct skb_seq_state
*st
);
1224 unsigned int skb_seq_read(unsigned int consumed
, const u8
**data
,
1225 struct skb_seq_state
*st
);
1226 void skb_abort_seq_read(struct skb_seq_state
*st
);
1228 unsigned int skb_find_text(struct sk_buff
*skb
, unsigned int from
,
1229 unsigned int to
, struct ts_config
*config
);
1232 * Packet hash types specify the type of hash in skb_set_hash.
1234 * Hash types refer to the protocol layer addresses which are used to
1235 * construct a packet's hash. The hashes are used to differentiate or identify
1236 * flows of the protocol layer for the hash type. Hash types are either
1237 * layer-2 (L2), layer-3 (L3), or layer-4 (L4).
1239 * Properties of hashes:
1241 * 1) Two packets in different flows have different hash values
1242 * 2) Two packets in the same flow should have the same hash value
1244 * A hash at a higher layer is considered to be more specific. A driver should
1245 * set the most specific hash possible.
1247 * A driver cannot indicate a more specific hash than the layer at which a hash
1248 * was computed. For instance an L3 hash cannot be set as an L4 hash.
1250 * A driver may indicate a hash level which is less specific than the
1251 * actual layer the hash was computed on. For instance, a hash computed
1252 * at L4 may be considered an L3 hash. This should only be done if the
1253 * driver can't unambiguously determine that the HW computed the hash at
1254 * the higher layer. Note that the "should" in the second property above
1257 enum pkt_hash_types
{
1258 PKT_HASH_TYPE_NONE
, /* Undefined type */
1259 PKT_HASH_TYPE_L2
, /* Input: src_MAC, dest_MAC */
1260 PKT_HASH_TYPE_L3
, /* Input: src_IP, dst_IP */
1261 PKT_HASH_TYPE_L4
, /* Input: src_IP, dst_IP, src_port, dst_port */
1264 static inline void skb_clear_hash(struct sk_buff
*skb
)
1271 static inline void skb_clear_hash_if_not_l4(struct sk_buff
*skb
)
1274 skb_clear_hash(skb
);
1278 __skb_set_hash(struct sk_buff
*skb
, __u32 hash
, bool is_sw
, bool is_l4
)
1280 skb
->l4_hash
= is_l4
;
1281 skb
->sw_hash
= is_sw
;
1286 skb_set_hash(struct sk_buff
*skb
, __u32 hash
, enum pkt_hash_types type
)
1288 /* Used by drivers to set hash from HW */
1289 __skb_set_hash(skb
, hash
, false, type
== PKT_HASH_TYPE_L4
);
1293 __skb_set_sw_hash(struct sk_buff
*skb
, __u32 hash
, bool is_l4
)
1295 __skb_set_hash(skb
, hash
, true, is_l4
);
1298 void __skb_get_hash(struct sk_buff
*skb
);
1299 u32
__skb_get_hash_symmetric(const struct sk_buff
*skb
);
1300 u32
skb_get_poff(const struct sk_buff
*skb
);
1301 u32
__skb_get_poff(const struct sk_buff
*skb
, const void *data
,
1302 const struct flow_keys_basic
*keys
, int hlen
);
1303 __be32
__skb_flow_get_ports(const struct sk_buff
*skb
, int thoff
, u8 ip_proto
,
1304 const void *data
, int hlen_proto
);
1306 static inline __be32
skb_flow_get_ports(const struct sk_buff
*skb
,
1307 int thoff
, u8 ip_proto
)
1309 return __skb_flow_get_ports(skb
, thoff
, ip_proto
, NULL
, 0);
1312 void skb_flow_dissector_init(struct flow_dissector
*flow_dissector
,
1313 const struct flow_dissector_key
*key
,
1314 unsigned int key_count
);
1316 struct bpf_flow_dissector
;
1317 bool bpf_flow_dissect(struct bpf_prog
*prog
, struct bpf_flow_dissector
*ctx
,
1318 __be16 proto
, int nhoff
, int hlen
, unsigned int flags
);
1320 bool __skb_flow_dissect(const struct net
*net
,
1321 const struct sk_buff
*skb
,
1322 struct flow_dissector
*flow_dissector
,
1323 void *target_container
, const void *data
,
1324 __be16 proto
, int nhoff
, int hlen
, unsigned int flags
);
1326 static inline bool skb_flow_dissect(const struct sk_buff
*skb
,
1327 struct flow_dissector
*flow_dissector
,
1328 void *target_container
, unsigned int flags
)
1330 return __skb_flow_dissect(NULL
, skb
, flow_dissector
,
1331 target_container
, NULL
, 0, 0, 0, flags
);
1334 static inline bool skb_flow_dissect_flow_keys(const struct sk_buff
*skb
,
1335 struct flow_keys
*flow
,
1338 memset(flow
, 0, sizeof(*flow
));
1339 return __skb_flow_dissect(NULL
, skb
, &flow_keys_dissector
,
1340 flow
, NULL
, 0, 0, 0, flags
);
1344 skb_flow_dissect_flow_keys_basic(const struct net
*net
,
1345 const struct sk_buff
*skb
,
1346 struct flow_keys_basic
*flow
,
1347 const void *data
, __be16 proto
,
1348 int nhoff
, int hlen
, unsigned int flags
)
1350 memset(flow
, 0, sizeof(*flow
));
1351 return __skb_flow_dissect(net
, skb
, &flow_keys_basic_dissector
, flow
,
1352 data
, proto
, nhoff
, hlen
, flags
);
1355 void skb_flow_dissect_meta(const struct sk_buff
*skb
,
1356 struct flow_dissector
*flow_dissector
,
1357 void *target_container
);
1359 /* Gets a skb connection tracking info, ctinfo map should be a
1360 * map of mapsize to translate enum ip_conntrack_info states
1364 skb_flow_dissect_ct(const struct sk_buff
*skb
,
1365 struct flow_dissector
*flow_dissector
,
1366 void *target_container
,
1367 u16
*ctinfo_map
, size_t mapsize
,
1370 skb_flow_dissect_tunnel_info(const struct sk_buff
*skb
,
1371 struct flow_dissector
*flow_dissector
,
1372 void *target_container
);
1374 void skb_flow_dissect_hash(const struct sk_buff
*skb
,
1375 struct flow_dissector
*flow_dissector
,
1376 void *target_container
);
1378 static inline __u32
skb_get_hash(struct sk_buff
*skb
)
1380 if (!skb
->l4_hash
&& !skb
->sw_hash
)
1381 __skb_get_hash(skb
);
1386 static inline __u32
skb_get_hash_flowi6(struct sk_buff
*skb
, const struct flowi6
*fl6
)
1388 if (!skb
->l4_hash
&& !skb
->sw_hash
) {
1389 struct flow_keys keys
;
1390 __u32 hash
= __get_hash_from_flowi6(fl6
, &keys
);
1392 __skb_set_sw_hash(skb
, hash
, flow_keys_have_l4(&keys
));
1398 __u32
skb_get_hash_perturb(const struct sk_buff
*skb
,
1399 const siphash_key_t
*perturb
);
1401 static inline __u32
skb_get_hash_raw(const struct sk_buff
*skb
)
1406 static inline void skb_copy_hash(struct sk_buff
*to
, const struct sk_buff
*from
)
1408 to
->hash
= from
->hash
;
1409 to
->sw_hash
= from
->sw_hash
;
1410 to
->l4_hash
= from
->l4_hash
;
1413 static inline void skb_copy_decrypted(struct sk_buff
*to
,
1414 const struct sk_buff
*from
)
1416 #ifdef CONFIG_TLS_DEVICE
1417 to
->decrypted
= from
->decrypted
;
1421 #ifdef NET_SKBUFF_DATA_USES_OFFSET
1422 static inline unsigned char *skb_end_pointer(const struct sk_buff
*skb
)
1424 return skb
->head
+ skb
->end
;
1427 static inline unsigned int skb_end_offset(const struct sk_buff
*skb
)
1432 static inline unsigned char *skb_end_pointer(const struct sk_buff
*skb
)
1437 static inline unsigned int skb_end_offset(const struct sk_buff
*skb
)
1439 return skb
->end
- skb
->head
;
1444 #define skb_shinfo(SKB) ((struct skb_shared_info *)(skb_end_pointer(SKB)))
1446 static inline struct skb_shared_hwtstamps
*skb_hwtstamps(struct sk_buff
*skb
)
1448 return &skb_shinfo(skb
)->hwtstamps
;
1451 static inline struct ubuf_info
*skb_zcopy(struct sk_buff
*skb
)
1453 bool is_zcopy
= skb
&& skb_shinfo(skb
)->flags
& SKBFL_ZEROCOPY_ENABLE
;
1455 return is_zcopy
? skb_uarg(skb
) : NULL
;
1458 static inline void net_zcopy_get(struct ubuf_info
*uarg
)
1460 refcount_inc(&uarg
->refcnt
);
1463 static inline void skb_zcopy_init(struct sk_buff
*skb
, struct ubuf_info
*uarg
)
1465 skb_shinfo(skb
)->destructor_arg
= uarg
;
1466 skb_shinfo(skb
)->flags
|= uarg
->flags
;
1469 static inline void skb_zcopy_set(struct sk_buff
*skb
, struct ubuf_info
*uarg
,
1472 if (skb
&& uarg
&& !skb_zcopy(skb
)) {
1473 if (unlikely(have_ref
&& *have_ref
))
1476 net_zcopy_get(uarg
);
1477 skb_zcopy_init(skb
, uarg
);
1481 static inline void skb_zcopy_set_nouarg(struct sk_buff
*skb
, void *val
)
1483 skb_shinfo(skb
)->destructor_arg
= (void *)((uintptr_t) val
| 0x1UL
);
1484 skb_shinfo(skb
)->flags
|= SKBFL_ZEROCOPY_FRAG
;
1487 static inline bool skb_zcopy_is_nouarg(struct sk_buff
*skb
)
1489 return (uintptr_t) skb_shinfo(skb
)->destructor_arg
& 0x1UL
;
1492 static inline void *skb_zcopy_get_nouarg(struct sk_buff
*skb
)
1494 return (void *)((uintptr_t) skb_shinfo(skb
)->destructor_arg
& ~0x1UL
);
1497 static inline void net_zcopy_put(struct ubuf_info
*uarg
)
1500 uarg
->callback(NULL
, uarg
, true);
1503 static inline void net_zcopy_put_abort(struct ubuf_info
*uarg
, bool have_uref
)
1506 if (uarg
->callback
== msg_zerocopy_callback
)
1507 msg_zerocopy_put_abort(uarg
, have_uref
);
1509 net_zcopy_put(uarg
);
1513 /* Release a reference on a zerocopy structure */
1514 static inline void skb_zcopy_clear(struct sk_buff
*skb
, bool zerocopy_success
)
1516 struct ubuf_info
*uarg
= skb_zcopy(skb
);
1519 if (!skb_zcopy_is_nouarg(skb
))
1520 uarg
->callback(skb
, uarg
, zerocopy_success
);
1522 skb_shinfo(skb
)->flags
&= ~SKBFL_ZEROCOPY_FRAG
;
1526 static inline void skb_mark_not_on_list(struct sk_buff
*skb
)
1531 /* Iterate through singly-linked GSO fragments of an skb. */
1532 #define skb_list_walk_safe(first, skb, next_skb) \
1533 for ((skb) = (first), (next_skb) = (skb) ? (skb)->next : NULL; (skb); \
1534 (skb) = (next_skb), (next_skb) = (skb) ? (skb)->next : NULL)
1536 static inline void skb_list_del_init(struct sk_buff
*skb
)
1538 __list_del_entry(&skb
->list
);
1539 skb_mark_not_on_list(skb
);
1543 * skb_queue_empty - check if a queue is empty
1546 * Returns true if the queue is empty, false otherwise.
1548 static inline int skb_queue_empty(const struct sk_buff_head
*list
)
1550 return list
->next
== (const struct sk_buff
*) list
;
1554 * skb_queue_empty_lockless - check if a queue is empty
1557 * Returns true if the queue is empty, false otherwise.
1558 * This variant can be used in lockless contexts.
1560 static inline bool skb_queue_empty_lockless(const struct sk_buff_head
*list
)
1562 return READ_ONCE(list
->next
) == (const struct sk_buff
*) list
;
1567 * skb_queue_is_last - check if skb is the last entry in the queue
1571 * Returns true if @skb is the last buffer on the list.
1573 static inline bool skb_queue_is_last(const struct sk_buff_head
*list
,
1574 const struct sk_buff
*skb
)
1576 return skb
->next
== (const struct sk_buff
*) list
;
1580 * skb_queue_is_first - check if skb is the first entry in the queue
1584 * Returns true if @skb is the first buffer on the list.
1586 static inline bool skb_queue_is_first(const struct sk_buff_head
*list
,
1587 const struct sk_buff
*skb
)
1589 return skb
->prev
== (const struct sk_buff
*) list
;
1593 * skb_queue_next - return the next packet in the queue
1595 * @skb: current buffer
1597 * Return the next packet in @list after @skb. It is only valid to
1598 * call this if skb_queue_is_last() evaluates to false.
1600 static inline struct sk_buff
*skb_queue_next(const struct sk_buff_head
*list
,
1601 const struct sk_buff
*skb
)
1603 /* This BUG_ON may seem severe, but if we just return then we
1604 * are going to dereference garbage.
1606 BUG_ON(skb_queue_is_last(list
, skb
));
1611 * skb_queue_prev - return the prev packet in the queue
1613 * @skb: current buffer
1615 * Return the prev packet in @list before @skb. It is only valid to
1616 * call this if skb_queue_is_first() evaluates to false.
1618 static inline struct sk_buff
*skb_queue_prev(const struct sk_buff_head
*list
,
1619 const struct sk_buff
*skb
)
1621 /* This BUG_ON may seem severe, but if we just return then we
1622 * are going to dereference garbage.
1624 BUG_ON(skb_queue_is_first(list
, skb
));
1629 * skb_get - reference buffer
1630 * @skb: buffer to reference
1632 * Makes another reference to a socket buffer and returns a pointer
1635 static inline struct sk_buff
*skb_get(struct sk_buff
*skb
)
1637 refcount_inc(&skb
->users
);
1642 * If users == 1, we are the only owner and can avoid redundant atomic changes.
1646 * skb_cloned - is the buffer a clone
1647 * @skb: buffer to check
1649 * Returns true if the buffer was generated with skb_clone() and is
1650 * one of multiple shared copies of the buffer. Cloned buffers are
1651 * shared data so must not be written to under normal circumstances.
1653 static inline int skb_cloned(const struct sk_buff
*skb
)
1655 return skb
->cloned
&&
1656 (atomic_read(&skb_shinfo(skb
)->dataref
) & SKB_DATAREF_MASK
) != 1;
1659 static inline int skb_unclone(struct sk_buff
*skb
, gfp_t pri
)
1661 might_sleep_if(gfpflags_allow_blocking(pri
));
1663 if (skb_cloned(skb
))
1664 return pskb_expand_head(skb
, 0, 0, pri
);
1670 * skb_header_cloned - is the header a clone
1671 * @skb: buffer to check
1673 * Returns true if modifying the header part of the buffer requires
1674 * the data to be copied.
1676 static inline int skb_header_cloned(const struct sk_buff
*skb
)
1683 dataref
= atomic_read(&skb_shinfo(skb
)->dataref
);
1684 dataref
= (dataref
& SKB_DATAREF_MASK
) - (dataref
>> SKB_DATAREF_SHIFT
);
1685 return dataref
!= 1;
1688 static inline int skb_header_unclone(struct sk_buff
*skb
, gfp_t pri
)
1690 might_sleep_if(gfpflags_allow_blocking(pri
));
1692 if (skb_header_cloned(skb
))
1693 return pskb_expand_head(skb
, 0, 0, pri
);
1699 * __skb_header_release - release reference to header
1700 * @skb: buffer to operate on
1702 static inline void __skb_header_release(struct sk_buff
*skb
)
1705 atomic_set(&skb_shinfo(skb
)->dataref
, 1 + (1 << SKB_DATAREF_SHIFT
));
1710 * skb_shared - is the buffer shared
1711 * @skb: buffer to check
1713 * Returns true if more than one person has a reference to this
1716 static inline int skb_shared(const struct sk_buff
*skb
)
1718 return refcount_read(&skb
->users
) != 1;
1722 * skb_share_check - check if buffer is shared and if so clone it
1723 * @skb: buffer to check
1724 * @pri: priority for memory allocation
1726 * If the buffer is shared the buffer is cloned and the old copy
1727 * drops a reference. A new clone with a single reference is returned.
1728 * If the buffer is not shared the original buffer is returned. When
1729 * being called from interrupt status or with spinlocks held pri must
1732 * NULL is returned on a memory allocation failure.
1734 static inline struct sk_buff
*skb_share_check(struct sk_buff
*skb
, gfp_t pri
)
1736 might_sleep_if(gfpflags_allow_blocking(pri
));
1737 if (skb_shared(skb
)) {
1738 struct sk_buff
*nskb
= skb_clone(skb
, pri
);
1750 * Copy shared buffers into a new sk_buff. We effectively do COW on
1751 * packets to handle cases where we have a local reader and forward
1752 * and a couple of other messy ones. The normal one is tcpdumping
1753 * a packet thats being forwarded.
1757 * skb_unshare - make a copy of a shared buffer
1758 * @skb: buffer to check
1759 * @pri: priority for memory allocation
1761 * If the socket buffer is a clone then this function creates a new
1762 * copy of the data, drops a reference count on the old copy and returns
1763 * the new copy with the reference count at 1. If the buffer is not a clone
1764 * the original buffer is returned. When called with a spinlock held or
1765 * from interrupt state @pri must be %GFP_ATOMIC
1767 * %NULL is returned on a memory allocation failure.
1769 static inline struct sk_buff
*skb_unshare(struct sk_buff
*skb
,
1772 might_sleep_if(gfpflags_allow_blocking(pri
));
1773 if (skb_cloned(skb
)) {
1774 struct sk_buff
*nskb
= skb_copy(skb
, pri
);
1776 /* Free our shared copy */
1787 * skb_peek - peek at the head of an &sk_buff_head
1788 * @list_: list to peek at
1790 * Peek an &sk_buff. Unlike most other operations you _MUST_
1791 * be careful with this one. A peek leaves the buffer on the
1792 * list and someone else may run off with it. You must hold
1793 * the appropriate locks or have a private queue to do this.
1795 * Returns %NULL for an empty list or a pointer to the head element.
1796 * The reference count is not incremented and the reference is therefore
1797 * volatile. Use with caution.
1799 static inline struct sk_buff
*skb_peek(const struct sk_buff_head
*list_
)
1801 struct sk_buff
*skb
= list_
->next
;
1803 if (skb
== (struct sk_buff
*)list_
)
1809 * __skb_peek - peek at the head of a non-empty &sk_buff_head
1810 * @list_: list to peek at
1812 * Like skb_peek(), but the caller knows that the list is not empty.
1814 static inline struct sk_buff
*__skb_peek(const struct sk_buff_head
*list_
)
1820 * skb_peek_next - peek skb following the given one from a queue
1821 * @skb: skb to start from
1822 * @list_: list to peek at
1824 * Returns %NULL when the end of the list is met or a pointer to the
1825 * next element. The reference count is not incremented and the
1826 * reference is therefore volatile. Use with caution.
1828 static inline struct sk_buff
*skb_peek_next(struct sk_buff
*skb
,
1829 const struct sk_buff_head
*list_
)
1831 struct sk_buff
*next
= skb
->next
;
1833 if (next
== (struct sk_buff
*)list_
)
1839 * skb_peek_tail - peek at the tail of an &sk_buff_head
1840 * @list_: list to peek at
1842 * Peek an &sk_buff. Unlike most other operations you _MUST_
1843 * be careful with this one. A peek leaves the buffer on the
1844 * list and someone else may run off with it. You must hold
1845 * the appropriate locks or have a private queue to do this.
1847 * Returns %NULL for an empty list or a pointer to the tail element.
1848 * The reference count is not incremented and the reference is therefore
1849 * volatile. Use with caution.
1851 static inline struct sk_buff
*skb_peek_tail(const struct sk_buff_head
*list_
)
1853 struct sk_buff
*skb
= READ_ONCE(list_
->prev
);
1855 if (skb
== (struct sk_buff
*)list_
)
1862 * skb_queue_len - get queue length
1863 * @list_: list to measure
1865 * Return the length of an &sk_buff queue.
1867 static inline __u32
skb_queue_len(const struct sk_buff_head
*list_
)
1873 * skb_queue_len_lockless - get queue length
1874 * @list_: list to measure
1876 * Return the length of an &sk_buff queue.
1877 * This variant can be used in lockless contexts.
1879 static inline __u32
skb_queue_len_lockless(const struct sk_buff_head
*list_
)
1881 return READ_ONCE(list_
->qlen
);
1885 * __skb_queue_head_init - initialize non-spinlock portions of sk_buff_head
1886 * @list: queue to initialize
1888 * This initializes only the list and queue length aspects of
1889 * an sk_buff_head object. This allows to initialize the list
1890 * aspects of an sk_buff_head without reinitializing things like
1891 * the spinlock. It can also be used for on-stack sk_buff_head
1892 * objects where the spinlock is known to not be used.
1894 static inline void __skb_queue_head_init(struct sk_buff_head
*list
)
1896 list
->prev
= list
->next
= (struct sk_buff
*)list
;
1901 * This function creates a split out lock class for each invocation;
1902 * this is needed for now since a whole lot of users of the skb-queue
1903 * infrastructure in drivers have different locking usage (in hardirq)
1904 * than the networking core (in softirq only). In the long run either the
1905 * network layer or drivers should need annotation to consolidate the
1906 * main types of usage into 3 classes.
1908 static inline void skb_queue_head_init(struct sk_buff_head
*list
)
1910 spin_lock_init(&list
->lock
);
1911 __skb_queue_head_init(list
);
1914 static inline void skb_queue_head_init_class(struct sk_buff_head
*list
,
1915 struct lock_class_key
*class)
1917 skb_queue_head_init(list
);
1918 lockdep_set_class(&list
->lock
, class);
1922 * Insert an sk_buff on a list.
1924 * The "__skb_xxxx()" functions are the non-atomic ones that
1925 * can only be called with interrupts disabled.
1927 static inline void __skb_insert(struct sk_buff
*newsk
,
1928 struct sk_buff
*prev
, struct sk_buff
*next
,
1929 struct sk_buff_head
*list
)
1931 /* See skb_queue_empty_lockless() and skb_peek_tail()
1932 * for the opposite READ_ONCE()
1934 WRITE_ONCE(newsk
->next
, next
);
1935 WRITE_ONCE(newsk
->prev
, prev
);
1936 WRITE_ONCE(next
->prev
, newsk
);
1937 WRITE_ONCE(prev
->next
, newsk
);
1941 static inline void __skb_queue_splice(const struct sk_buff_head
*list
,
1942 struct sk_buff
*prev
,
1943 struct sk_buff
*next
)
1945 struct sk_buff
*first
= list
->next
;
1946 struct sk_buff
*last
= list
->prev
;
1948 WRITE_ONCE(first
->prev
, prev
);
1949 WRITE_ONCE(prev
->next
, first
);
1951 WRITE_ONCE(last
->next
, next
);
1952 WRITE_ONCE(next
->prev
, last
);
1956 * skb_queue_splice - join two skb lists, this is designed for stacks
1957 * @list: the new list to add
1958 * @head: the place to add it in the first list
1960 static inline void skb_queue_splice(const struct sk_buff_head
*list
,
1961 struct sk_buff_head
*head
)
1963 if (!skb_queue_empty(list
)) {
1964 __skb_queue_splice(list
, (struct sk_buff
*) head
, head
->next
);
1965 head
->qlen
+= list
->qlen
;
1970 * skb_queue_splice_init - join two skb lists and reinitialise the emptied list
1971 * @list: the new list to add
1972 * @head: the place to add it in the first list
1974 * The list at @list is reinitialised
1976 static inline void skb_queue_splice_init(struct sk_buff_head
*list
,
1977 struct sk_buff_head
*head
)
1979 if (!skb_queue_empty(list
)) {
1980 __skb_queue_splice(list
, (struct sk_buff
*) head
, head
->next
);
1981 head
->qlen
+= list
->qlen
;
1982 __skb_queue_head_init(list
);
1987 * skb_queue_splice_tail - join two skb lists, each list being a queue
1988 * @list: the new list to add
1989 * @head: the place to add it in the first list
1991 static inline void skb_queue_splice_tail(const struct sk_buff_head
*list
,
1992 struct sk_buff_head
*head
)
1994 if (!skb_queue_empty(list
)) {
1995 __skb_queue_splice(list
, head
->prev
, (struct sk_buff
*) head
);
1996 head
->qlen
+= list
->qlen
;
2001 * skb_queue_splice_tail_init - join two skb lists and reinitialise the emptied list
2002 * @list: the new list to add
2003 * @head: the place to add it in the first list
2005 * Each of the lists is a queue.
2006 * The list at @list is reinitialised
2008 static inline void skb_queue_splice_tail_init(struct sk_buff_head
*list
,
2009 struct sk_buff_head
*head
)
2011 if (!skb_queue_empty(list
)) {
2012 __skb_queue_splice(list
, head
->prev
, (struct sk_buff
*) head
);
2013 head
->qlen
+= list
->qlen
;
2014 __skb_queue_head_init(list
);
2019 * __skb_queue_after - queue a buffer at the list head
2020 * @list: list to use
2021 * @prev: place after this buffer
2022 * @newsk: buffer to queue
2024 * Queue a buffer int the middle of a list. This function takes no locks
2025 * and you must therefore hold required locks before calling it.
2027 * A buffer cannot be placed on two lists at the same time.
2029 static inline void __skb_queue_after(struct sk_buff_head
*list
,
2030 struct sk_buff
*prev
,
2031 struct sk_buff
*newsk
)
2033 __skb_insert(newsk
, prev
, prev
->next
, list
);
2036 void skb_append(struct sk_buff
*old
, struct sk_buff
*newsk
,
2037 struct sk_buff_head
*list
);
2039 static inline void __skb_queue_before(struct sk_buff_head
*list
,
2040 struct sk_buff
*next
,
2041 struct sk_buff
*newsk
)
2043 __skb_insert(newsk
, next
->prev
, next
, list
);
2047 * __skb_queue_head - queue a buffer at the list head
2048 * @list: list to use
2049 * @newsk: buffer to queue
2051 * Queue a buffer at the start of a list. This function takes no locks
2052 * and you must therefore hold required locks before calling it.
2054 * A buffer cannot be placed on two lists at the same time.
2056 static inline void __skb_queue_head(struct sk_buff_head
*list
,
2057 struct sk_buff
*newsk
)
2059 __skb_queue_after(list
, (struct sk_buff
*)list
, newsk
);
2061 void skb_queue_head(struct sk_buff_head
*list
, struct sk_buff
*newsk
);
2064 * __skb_queue_tail - queue a buffer at the list tail
2065 * @list: list to use
2066 * @newsk: buffer to queue
2068 * Queue a buffer at the end of a list. This function takes no locks
2069 * and you must therefore hold required locks before calling it.
2071 * A buffer cannot be placed on two lists at the same time.
2073 static inline void __skb_queue_tail(struct sk_buff_head
*list
,
2074 struct sk_buff
*newsk
)
2076 __skb_queue_before(list
, (struct sk_buff
*)list
, newsk
);
2078 void skb_queue_tail(struct sk_buff_head
*list
, struct sk_buff
*newsk
);
2081 * remove sk_buff from list. _Must_ be called atomically, and with
2084 void skb_unlink(struct sk_buff
*skb
, struct sk_buff_head
*list
);
2085 static inline void __skb_unlink(struct sk_buff
*skb
, struct sk_buff_head
*list
)
2087 struct sk_buff
*next
, *prev
;
2089 WRITE_ONCE(list
->qlen
, list
->qlen
- 1);
2092 skb
->next
= skb
->prev
= NULL
;
2093 WRITE_ONCE(next
->prev
, prev
);
2094 WRITE_ONCE(prev
->next
, next
);
2098 * __skb_dequeue - remove from the head of the queue
2099 * @list: list to dequeue from
2101 * Remove the head of the list. This function does not take any locks
2102 * so must be used with appropriate locks held only. The head item is
2103 * returned or %NULL if the list is empty.
2105 static inline struct sk_buff
*__skb_dequeue(struct sk_buff_head
*list
)
2107 struct sk_buff
*skb
= skb_peek(list
);
2109 __skb_unlink(skb
, list
);
2112 struct sk_buff
*skb_dequeue(struct sk_buff_head
*list
);
2115 * __skb_dequeue_tail - remove from the tail of the queue
2116 * @list: list to dequeue from
2118 * Remove the tail of the list. This function does not take any locks
2119 * so must be used with appropriate locks held only. The tail item is
2120 * returned or %NULL if the list is empty.
2122 static inline struct sk_buff
*__skb_dequeue_tail(struct sk_buff_head
*list
)
2124 struct sk_buff
*skb
= skb_peek_tail(list
);
2126 __skb_unlink(skb
, list
);
2129 struct sk_buff
*skb_dequeue_tail(struct sk_buff_head
*list
);
2132 static inline bool skb_is_nonlinear(const struct sk_buff
*skb
)
2134 return skb
->data_len
;
2137 static inline unsigned int skb_headlen(const struct sk_buff
*skb
)
2139 return skb
->len
- skb
->data_len
;
2142 static inline unsigned int __skb_pagelen(const struct sk_buff
*skb
)
2144 unsigned int i
, len
= 0;
2146 for (i
= skb_shinfo(skb
)->nr_frags
- 1; (int)i
>= 0; i
--)
2147 len
+= skb_frag_size(&skb_shinfo(skb
)->frags
[i
]);
2151 static inline unsigned int skb_pagelen(const struct sk_buff
*skb
)
2153 return skb_headlen(skb
) + __skb_pagelen(skb
);
2157 * __skb_fill_page_desc - initialise a paged fragment in an skb
2158 * @skb: buffer containing fragment to be initialised
2159 * @i: paged fragment index to initialise
2160 * @page: the page to use for this fragment
2161 * @off: the offset to the data with @page
2162 * @size: the length of the data
2164 * Initialises the @i'th fragment of @skb to point to &size bytes at
2165 * offset @off within @page.
2167 * Does not take any additional reference on the fragment.
2169 static inline void __skb_fill_page_desc(struct sk_buff
*skb
, int i
,
2170 struct page
*page
, int off
, int size
)
2172 skb_frag_t
*frag
= &skb_shinfo(skb
)->frags
[i
];
2175 * Propagate page pfmemalloc to the skb if we can. The problem is
2176 * that not all callers have unique ownership of the page but rely
2177 * on page_is_pfmemalloc doing the right thing(tm).
2179 frag
->bv_page
= page
;
2180 frag
->bv_offset
= off
;
2181 skb_frag_size_set(frag
, size
);
2183 page
= compound_head(page
);
2184 if (page_is_pfmemalloc(page
))
2185 skb
->pfmemalloc
= true;
2189 * skb_fill_page_desc - initialise a paged fragment in an skb
2190 * @skb: buffer containing fragment to be initialised
2191 * @i: paged fragment index to initialise
2192 * @page: the page to use for this fragment
2193 * @off: the offset to the data with @page
2194 * @size: the length of the data
2196 * As per __skb_fill_page_desc() -- initialises the @i'th fragment of
2197 * @skb to point to @size bytes at offset @off within @page. In
2198 * addition updates @skb such that @i is the last fragment.
2200 * Does not take any additional reference on the fragment.
2202 static inline void skb_fill_page_desc(struct sk_buff
*skb
, int i
,
2203 struct page
*page
, int off
, int size
)
2205 __skb_fill_page_desc(skb
, i
, page
, off
, size
);
2206 skb_shinfo(skb
)->nr_frags
= i
+ 1;
2209 void skb_add_rx_frag(struct sk_buff
*skb
, int i
, struct page
*page
, int off
,
2210 int size
, unsigned int truesize
);
2212 void skb_coalesce_rx_frag(struct sk_buff
*skb
, int i
, int size
,
2213 unsigned int truesize
);
2215 #define SKB_LINEAR_ASSERT(skb) BUG_ON(skb_is_nonlinear(skb))
2217 #ifdef NET_SKBUFF_DATA_USES_OFFSET
2218 static inline unsigned char *skb_tail_pointer(const struct sk_buff
*skb
)
2220 return skb
->head
+ skb
->tail
;
2223 static inline void skb_reset_tail_pointer(struct sk_buff
*skb
)
2225 skb
->tail
= skb
->data
- skb
->head
;
2228 static inline void skb_set_tail_pointer(struct sk_buff
*skb
, const int offset
)
2230 skb_reset_tail_pointer(skb
);
2231 skb
->tail
+= offset
;
2234 #else /* NET_SKBUFF_DATA_USES_OFFSET */
2235 static inline unsigned char *skb_tail_pointer(const struct sk_buff
*skb
)
2240 static inline void skb_reset_tail_pointer(struct sk_buff
*skb
)
2242 skb
->tail
= skb
->data
;
2245 static inline void skb_set_tail_pointer(struct sk_buff
*skb
, const int offset
)
2247 skb
->tail
= skb
->data
+ offset
;
2250 #endif /* NET_SKBUFF_DATA_USES_OFFSET */
2253 * Add data to an sk_buff
2255 void *pskb_put(struct sk_buff
*skb
, struct sk_buff
*tail
, int len
);
2256 void *skb_put(struct sk_buff
*skb
, unsigned int len
);
2257 static inline void *__skb_put(struct sk_buff
*skb
, unsigned int len
)
2259 void *tmp
= skb_tail_pointer(skb
);
2260 SKB_LINEAR_ASSERT(skb
);
2266 static inline void *__skb_put_zero(struct sk_buff
*skb
, unsigned int len
)
2268 void *tmp
= __skb_put(skb
, len
);
2270 memset(tmp
, 0, len
);
2274 static inline void *__skb_put_data(struct sk_buff
*skb
, const void *data
,
2277 void *tmp
= __skb_put(skb
, len
);
2279 memcpy(tmp
, data
, len
);
2283 static inline void __skb_put_u8(struct sk_buff
*skb
, u8 val
)
2285 *(u8
*)__skb_put(skb
, 1) = val
;
2288 static inline void *skb_put_zero(struct sk_buff
*skb
, unsigned int len
)
2290 void *tmp
= skb_put(skb
, len
);
2292 memset(tmp
, 0, len
);
2297 static inline void *skb_put_data(struct sk_buff
*skb
, const void *data
,
2300 void *tmp
= skb_put(skb
, len
);
2302 memcpy(tmp
, data
, len
);
2307 static inline void skb_put_u8(struct sk_buff
*skb
, u8 val
)
2309 *(u8
*)skb_put(skb
, 1) = val
;
2312 void *skb_push(struct sk_buff
*skb
, unsigned int len
);
2313 static inline void *__skb_push(struct sk_buff
*skb
, unsigned int len
)
2320 void *skb_pull(struct sk_buff
*skb
, unsigned int len
);
2321 static inline void *__skb_pull(struct sk_buff
*skb
, unsigned int len
)
2324 BUG_ON(skb
->len
< skb
->data_len
);
2325 return skb
->data
+= len
;
2328 static inline void *skb_pull_inline(struct sk_buff
*skb
, unsigned int len
)
2330 return unlikely(len
> skb
->len
) ? NULL
: __skb_pull(skb
, len
);
2333 void *__pskb_pull_tail(struct sk_buff
*skb
, int delta
);
2335 static inline void *__pskb_pull(struct sk_buff
*skb
, unsigned int len
)
2337 if (len
> skb_headlen(skb
) &&
2338 !__pskb_pull_tail(skb
, len
- skb_headlen(skb
)))
2341 return skb
->data
+= len
;
2344 static inline void *pskb_pull(struct sk_buff
*skb
, unsigned int len
)
2346 return unlikely(len
> skb
->len
) ? NULL
: __pskb_pull(skb
, len
);
2349 static inline bool pskb_may_pull(struct sk_buff
*skb
, unsigned int len
)
2351 if (likely(len
<= skb_headlen(skb
)))
2353 if (unlikely(len
> skb
->len
))
2355 return __pskb_pull_tail(skb
, len
- skb_headlen(skb
)) != NULL
;
2358 void skb_condense(struct sk_buff
*skb
);
2361 * skb_headroom - bytes at buffer head
2362 * @skb: buffer to check
2364 * Return the number of bytes of free space at the head of an &sk_buff.
2366 static inline unsigned int skb_headroom(const struct sk_buff
*skb
)
2368 return skb
->data
- skb
->head
;
2372 * skb_tailroom - bytes at buffer end
2373 * @skb: buffer to check
2375 * Return the number of bytes of free space at the tail of an sk_buff
2377 static inline int skb_tailroom(const struct sk_buff
*skb
)
2379 return skb_is_nonlinear(skb
) ? 0 : skb
->end
- skb
->tail
;
2383 * skb_availroom - bytes at buffer end
2384 * @skb: buffer to check
2386 * Return the number of bytes of free space at the tail of an sk_buff
2387 * allocated by sk_stream_alloc()
2389 static inline int skb_availroom(const struct sk_buff
*skb
)
2391 if (skb_is_nonlinear(skb
))
2394 return skb
->end
- skb
->tail
- skb
->reserved_tailroom
;
2398 * skb_reserve - adjust headroom
2399 * @skb: buffer to alter
2400 * @len: bytes to move
2402 * Increase the headroom of an empty &sk_buff by reducing the tail
2403 * room. This is only allowed for an empty buffer.
2405 static inline void skb_reserve(struct sk_buff
*skb
, int len
)
2412 * skb_tailroom_reserve - adjust reserved_tailroom
2413 * @skb: buffer to alter
2414 * @mtu: maximum amount of headlen permitted
2415 * @needed_tailroom: minimum amount of reserved_tailroom
2417 * Set reserved_tailroom so that headlen can be as large as possible but
2418 * not larger than mtu and tailroom cannot be smaller than
2420 * The required headroom should already have been reserved before using
2423 static inline void skb_tailroom_reserve(struct sk_buff
*skb
, unsigned int mtu
,
2424 unsigned int needed_tailroom
)
2426 SKB_LINEAR_ASSERT(skb
);
2427 if (mtu
< skb_tailroom(skb
) - needed_tailroom
)
2428 /* use at most mtu */
2429 skb
->reserved_tailroom
= skb_tailroom(skb
) - mtu
;
2431 /* use up to all available space */
2432 skb
->reserved_tailroom
= needed_tailroom
;
2435 #define ENCAP_TYPE_ETHER 0
2436 #define ENCAP_TYPE_IPPROTO 1
2438 static inline void skb_set_inner_protocol(struct sk_buff
*skb
,
2441 skb
->inner_protocol
= protocol
;
2442 skb
->inner_protocol_type
= ENCAP_TYPE_ETHER
;
2445 static inline void skb_set_inner_ipproto(struct sk_buff
*skb
,
2448 skb
->inner_ipproto
= ipproto
;
2449 skb
->inner_protocol_type
= ENCAP_TYPE_IPPROTO
;
2452 static inline void skb_reset_inner_headers(struct sk_buff
*skb
)
2454 skb
->inner_mac_header
= skb
->mac_header
;
2455 skb
->inner_network_header
= skb
->network_header
;
2456 skb
->inner_transport_header
= skb
->transport_header
;
2459 static inline void skb_reset_mac_len(struct sk_buff
*skb
)
2461 skb
->mac_len
= skb
->network_header
- skb
->mac_header
;
2464 static inline unsigned char *skb_inner_transport_header(const struct sk_buff
2467 return skb
->head
+ skb
->inner_transport_header
;
2470 static inline int skb_inner_transport_offset(const struct sk_buff
*skb
)
2472 return skb_inner_transport_header(skb
) - skb
->data
;
2475 static inline void skb_reset_inner_transport_header(struct sk_buff
*skb
)
2477 skb
->inner_transport_header
= skb
->data
- skb
->head
;
2480 static inline void skb_set_inner_transport_header(struct sk_buff
*skb
,
2483 skb_reset_inner_transport_header(skb
);
2484 skb
->inner_transport_header
+= offset
;
2487 static inline unsigned char *skb_inner_network_header(const struct sk_buff
*skb
)
2489 return skb
->head
+ skb
->inner_network_header
;
2492 static inline void skb_reset_inner_network_header(struct sk_buff
*skb
)
2494 skb
->inner_network_header
= skb
->data
- skb
->head
;
2497 static inline void skb_set_inner_network_header(struct sk_buff
*skb
,
2500 skb_reset_inner_network_header(skb
);
2501 skb
->inner_network_header
+= offset
;
2504 static inline unsigned char *skb_inner_mac_header(const struct sk_buff
*skb
)
2506 return skb
->head
+ skb
->inner_mac_header
;
2509 static inline void skb_reset_inner_mac_header(struct sk_buff
*skb
)
2511 skb
->inner_mac_header
= skb
->data
- skb
->head
;
2514 static inline void skb_set_inner_mac_header(struct sk_buff
*skb
,
2517 skb_reset_inner_mac_header(skb
);
2518 skb
->inner_mac_header
+= offset
;
2520 static inline bool skb_transport_header_was_set(const struct sk_buff
*skb
)
2522 return skb
->transport_header
!= (typeof(skb
->transport_header
))~0U;
2525 static inline unsigned char *skb_transport_header(const struct sk_buff
*skb
)
2527 return skb
->head
+ skb
->transport_header
;
2530 static inline void skb_reset_transport_header(struct sk_buff
*skb
)
2532 skb
->transport_header
= skb
->data
- skb
->head
;
2535 static inline void skb_set_transport_header(struct sk_buff
*skb
,
2538 skb_reset_transport_header(skb
);
2539 skb
->transport_header
+= offset
;
2542 static inline unsigned char *skb_network_header(const struct sk_buff
*skb
)
2544 return skb
->head
+ skb
->network_header
;
2547 static inline void skb_reset_network_header(struct sk_buff
*skb
)
2549 skb
->network_header
= skb
->data
- skb
->head
;
2552 static inline void skb_set_network_header(struct sk_buff
*skb
, const int offset
)
2554 skb_reset_network_header(skb
);
2555 skb
->network_header
+= offset
;
2558 static inline unsigned char *skb_mac_header(const struct sk_buff
*skb
)
2560 return skb
->head
+ skb
->mac_header
;
2563 static inline int skb_mac_offset(const struct sk_buff
*skb
)
2565 return skb_mac_header(skb
) - skb
->data
;
2568 static inline u32
skb_mac_header_len(const struct sk_buff
*skb
)
2570 return skb
->network_header
- skb
->mac_header
;
2573 static inline int skb_mac_header_was_set(const struct sk_buff
*skb
)
2575 return skb
->mac_header
!= (typeof(skb
->mac_header
))~0U;
2578 static inline void skb_unset_mac_header(struct sk_buff
*skb
)
2580 skb
->mac_header
= (typeof(skb
->mac_header
))~0U;
2583 static inline void skb_reset_mac_header(struct sk_buff
*skb
)
2585 skb
->mac_header
= skb
->data
- skb
->head
;
2588 static inline void skb_set_mac_header(struct sk_buff
*skb
, const int offset
)
2590 skb_reset_mac_header(skb
);
2591 skb
->mac_header
+= offset
;
2594 static inline void skb_pop_mac_header(struct sk_buff
*skb
)
2596 skb
->mac_header
= skb
->network_header
;
2599 static inline void skb_probe_transport_header(struct sk_buff
*skb
)
2601 struct flow_keys_basic keys
;
2603 if (skb_transport_header_was_set(skb
))
2606 if (skb_flow_dissect_flow_keys_basic(NULL
, skb
, &keys
,
2608 skb_set_transport_header(skb
, keys
.control
.thoff
);
2611 static inline void skb_mac_header_rebuild(struct sk_buff
*skb
)
2613 if (skb_mac_header_was_set(skb
)) {
2614 const unsigned char *old_mac
= skb_mac_header(skb
);
2616 skb_set_mac_header(skb
, -skb
->mac_len
);
2617 memmove(skb_mac_header(skb
), old_mac
, skb
->mac_len
);
2621 static inline int skb_checksum_start_offset(const struct sk_buff
*skb
)
2623 return skb
->csum_start
- skb_headroom(skb
);
2626 static inline unsigned char *skb_checksum_start(const struct sk_buff
*skb
)
2628 return skb
->head
+ skb
->csum_start
;
2631 static inline int skb_transport_offset(const struct sk_buff
*skb
)
2633 return skb_transport_header(skb
) - skb
->data
;
2636 static inline u32
skb_network_header_len(const struct sk_buff
*skb
)
2638 return skb
->transport_header
- skb
->network_header
;
2641 static inline u32
skb_inner_network_header_len(const struct sk_buff
*skb
)
2643 return skb
->inner_transport_header
- skb
->inner_network_header
;
2646 static inline int skb_network_offset(const struct sk_buff
*skb
)
2648 return skb_network_header(skb
) - skb
->data
;
2651 static inline int skb_inner_network_offset(const struct sk_buff
*skb
)
2653 return skb_inner_network_header(skb
) - skb
->data
;
2656 static inline int pskb_network_may_pull(struct sk_buff
*skb
, unsigned int len
)
2658 return pskb_may_pull(skb
, skb_network_offset(skb
) + len
);
2662 * CPUs often take a performance hit when accessing unaligned memory
2663 * locations. The actual performance hit varies, it can be small if the
2664 * hardware handles it or large if we have to take an exception and fix it
2667 * Since an ethernet header is 14 bytes network drivers often end up with
2668 * the IP header at an unaligned offset. The IP header can be aligned by
2669 * shifting the start of the packet by 2 bytes. Drivers should do this
2672 * skb_reserve(skb, NET_IP_ALIGN);
2674 * The downside to this alignment of the IP header is that the DMA is now
2675 * unaligned. On some architectures the cost of an unaligned DMA is high
2676 * and this cost outweighs the gains made by aligning the IP header.
2678 * Since this trade off varies between architectures, we allow NET_IP_ALIGN
2681 #ifndef NET_IP_ALIGN
2682 #define NET_IP_ALIGN 2
2686 * The networking layer reserves some headroom in skb data (via
2687 * dev_alloc_skb). This is used to avoid having to reallocate skb data when
2688 * the header has to grow. In the default case, if the header has to grow
2689 * 32 bytes or less we avoid the reallocation.
2691 * Unfortunately this headroom changes the DMA alignment of the resulting
2692 * network packet. As for NET_IP_ALIGN, this unaligned DMA is expensive
2693 * on some architectures. An architecture can override this value,
2694 * perhaps setting it to a cacheline in size (since that will maintain
2695 * cacheline alignment of the DMA). It must be a power of 2.
2697 * Various parts of the networking layer expect at least 32 bytes of
2698 * headroom, you should not reduce this.
2700 * Using max(32, L1_CACHE_BYTES) makes sense (especially with RPS)
2701 * to reduce average number of cache lines per packet.
2702 * get_rps_cpu() for example only access one 64 bytes aligned block :
2703 * NET_IP_ALIGN(2) + ethernet_header(14) + IP_header(20/40) + ports(8)
2706 #define NET_SKB_PAD max(32, L1_CACHE_BYTES)
2709 int ___pskb_trim(struct sk_buff
*skb
, unsigned int len
);
2711 static inline void __skb_set_length(struct sk_buff
*skb
, unsigned int len
)
2713 if (WARN_ON(skb_is_nonlinear(skb
)))
2716 skb_set_tail_pointer(skb
, len
);
2719 static inline void __skb_trim(struct sk_buff
*skb
, unsigned int len
)
2721 __skb_set_length(skb
, len
);
2724 void skb_trim(struct sk_buff
*skb
, unsigned int len
);
2726 static inline int __pskb_trim(struct sk_buff
*skb
, unsigned int len
)
2729 return ___pskb_trim(skb
, len
);
2730 __skb_trim(skb
, len
);
2734 static inline int pskb_trim(struct sk_buff
*skb
, unsigned int len
)
2736 return (len
< skb
->len
) ? __pskb_trim(skb
, len
) : 0;
2740 * pskb_trim_unique - remove end from a paged unique (not cloned) buffer
2741 * @skb: buffer to alter
2744 * This is identical to pskb_trim except that the caller knows that
2745 * the skb is not cloned so we should never get an error due to out-
2748 static inline void pskb_trim_unique(struct sk_buff
*skb
, unsigned int len
)
2750 int err
= pskb_trim(skb
, len
);
2754 static inline int __skb_grow(struct sk_buff
*skb
, unsigned int len
)
2756 unsigned int diff
= len
- skb
->len
;
2758 if (skb_tailroom(skb
) < diff
) {
2759 int ret
= pskb_expand_head(skb
, 0, diff
- skb_tailroom(skb
),
2764 __skb_set_length(skb
, len
);
2769 * skb_orphan - orphan a buffer
2770 * @skb: buffer to orphan
2772 * If a buffer currently has an owner then we call the owner's
2773 * destructor function and make the @skb unowned. The buffer continues
2774 * to exist but is no longer charged to its former owner.
2776 static inline void skb_orphan(struct sk_buff
*skb
)
2778 if (skb
->destructor
) {
2779 skb
->destructor(skb
);
2780 skb
->destructor
= NULL
;
2788 * skb_orphan_frags - orphan the frags contained in a buffer
2789 * @skb: buffer to orphan frags from
2790 * @gfp_mask: allocation mask for replacement pages
2792 * For each frag in the SKB which needs a destructor (i.e. has an
2793 * owner) create a copy of that frag and release the original
2794 * page by calling the destructor.
2796 static inline int skb_orphan_frags(struct sk_buff
*skb
, gfp_t gfp_mask
)
2798 if (likely(!skb_zcopy(skb
)))
2800 if (!skb_zcopy_is_nouarg(skb
) &&
2801 skb_uarg(skb
)->callback
== msg_zerocopy_callback
)
2803 return skb_copy_ubufs(skb
, gfp_mask
);
2806 /* Frags must be orphaned, even if refcounted, if skb might loop to rx path */
2807 static inline int skb_orphan_frags_rx(struct sk_buff
*skb
, gfp_t gfp_mask
)
2809 if (likely(!skb_zcopy(skb
)))
2811 return skb_copy_ubufs(skb
, gfp_mask
);
2815 * __skb_queue_purge - empty a list
2816 * @list: list to empty
2818 * Delete all buffers on an &sk_buff list. Each buffer is removed from
2819 * the list and one reference dropped. This function does not take the
2820 * list lock and the caller must hold the relevant locks to use it.
2822 static inline void __skb_queue_purge(struct sk_buff_head
*list
)
2824 struct sk_buff
*skb
;
2825 while ((skb
= __skb_dequeue(list
)) != NULL
)
2828 void skb_queue_purge(struct sk_buff_head
*list
);
2830 unsigned int skb_rbtree_purge(struct rb_root
*root
);
2832 void *__netdev_alloc_frag_align(unsigned int fragsz
, unsigned int align_mask
);
2835 * netdev_alloc_frag - allocate a page fragment
2836 * @fragsz: fragment size
2838 * Allocates a frag from a page for receive buffer.
2839 * Uses GFP_ATOMIC allocations.
2841 static inline void *netdev_alloc_frag(unsigned int fragsz
)
2843 return __netdev_alloc_frag_align(fragsz
, ~0u);
2846 static inline void *netdev_alloc_frag_align(unsigned int fragsz
,
2849 WARN_ON_ONCE(!is_power_of_2(align
));
2850 return __netdev_alloc_frag_align(fragsz
, -align
);
2853 struct sk_buff
*__netdev_alloc_skb(struct net_device
*dev
, unsigned int length
,
2857 * netdev_alloc_skb - allocate an skbuff for rx on a specific device
2858 * @dev: network device to receive on
2859 * @length: length to allocate
2861 * Allocate a new &sk_buff and assign it a usage count of one. The
2862 * buffer has unspecified headroom built in. Users should allocate
2863 * the headroom they think they need without accounting for the
2864 * built in space. The built in space is used for optimisations.
2866 * %NULL is returned if there is no free memory. Although this function
2867 * allocates memory it can be called from an interrupt.
2869 static inline struct sk_buff
*netdev_alloc_skb(struct net_device
*dev
,
2870 unsigned int length
)
2872 return __netdev_alloc_skb(dev
, length
, GFP_ATOMIC
);
2875 /* legacy helper around __netdev_alloc_skb() */
2876 static inline struct sk_buff
*__dev_alloc_skb(unsigned int length
,
2879 return __netdev_alloc_skb(NULL
, length
, gfp_mask
);
2882 /* legacy helper around netdev_alloc_skb() */
2883 static inline struct sk_buff
*dev_alloc_skb(unsigned int length
)
2885 return netdev_alloc_skb(NULL
, length
);
2889 static inline struct sk_buff
*__netdev_alloc_skb_ip_align(struct net_device
*dev
,
2890 unsigned int length
, gfp_t gfp
)
2892 struct sk_buff
*skb
= __netdev_alloc_skb(dev
, length
+ NET_IP_ALIGN
, gfp
);
2894 if (NET_IP_ALIGN
&& skb
)
2895 skb_reserve(skb
, NET_IP_ALIGN
);
2899 static inline struct sk_buff
*netdev_alloc_skb_ip_align(struct net_device
*dev
,
2900 unsigned int length
)
2902 return __netdev_alloc_skb_ip_align(dev
, length
, GFP_ATOMIC
);
2905 static inline void skb_free_frag(void *addr
)
2907 page_frag_free(addr
);
2910 void *__napi_alloc_frag_align(unsigned int fragsz
, unsigned int align_mask
);
2912 static inline void *napi_alloc_frag(unsigned int fragsz
)
2914 return __napi_alloc_frag_align(fragsz
, ~0u);
2917 static inline void *napi_alloc_frag_align(unsigned int fragsz
,
2920 WARN_ON_ONCE(!is_power_of_2(align
));
2921 return __napi_alloc_frag_align(fragsz
, -align
);
2924 struct sk_buff
*__napi_alloc_skb(struct napi_struct
*napi
,
2925 unsigned int length
, gfp_t gfp_mask
);
2926 static inline struct sk_buff
*napi_alloc_skb(struct napi_struct
*napi
,
2927 unsigned int length
)
2929 return __napi_alloc_skb(napi
, length
, GFP_ATOMIC
);
2931 void napi_consume_skb(struct sk_buff
*skb
, int budget
);
2933 void napi_skb_free_stolen_head(struct sk_buff
*skb
);
2934 void __kfree_skb_defer(struct sk_buff
*skb
);
2937 * __dev_alloc_pages - allocate page for network Rx
2938 * @gfp_mask: allocation priority. Set __GFP_NOMEMALLOC if not for network Rx
2939 * @order: size of the allocation
2941 * Allocate a new page.
2943 * %NULL is returned if there is no free memory.
2945 static inline struct page
*__dev_alloc_pages(gfp_t gfp_mask
,
2948 /* This piece of code contains several assumptions.
2949 * 1. This is for device Rx, therefor a cold page is preferred.
2950 * 2. The expectation is the user wants a compound page.
2951 * 3. If requesting a order 0 page it will not be compound
2952 * due to the check to see if order has a value in prep_new_page
2953 * 4. __GFP_MEMALLOC is ignored if __GFP_NOMEMALLOC is set due to
2954 * code in gfp_to_alloc_flags that should be enforcing this.
2956 gfp_mask
|= __GFP_COMP
| __GFP_MEMALLOC
;
2958 return alloc_pages_node(NUMA_NO_NODE
, gfp_mask
, order
);
2961 static inline struct page
*dev_alloc_pages(unsigned int order
)
2963 return __dev_alloc_pages(GFP_ATOMIC
| __GFP_NOWARN
, order
);
2967 * __dev_alloc_page - allocate a page for network Rx
2968 * @gfp_mask: allocation priority. Set __GFP_NOMEMALLOC if not for network Rx
2970 * Allocate a new page.
2972 * %NULL is returned if there is no free memory.
2974 static inline struct page
*__dev_alloc_page(gfp_t gfp_mask
)
2976 return __dev_alloc_pages(gfp_mask
, 0);
2979 static inline struct page
*dev_alloc_page(void)
2981 return dev_alloc_pages(0);
2985 * dev_page_is_reusable - check whether a page can be reused for network Rx
2986 * @page: the page to test
2988 * A page shouldn't be considered for reusing/recycling if it was allocated
2989 * under memory pressure or at a distant memory node.
2991 * Returns false if this page should be returned to page allocator, true
2994 static inline bool dev_page_is_reusable(const struct page
*page
)
2996 return likely(page_to_nid(page
) == numa_mem_id() &&
2997 !page_is_pfmemalloc(page
));
3001 * skb_propagate_pfmemalloc - Propagate pfmemalloc if skb is allocated after RX page
3002 * @page: The page that was allocated from skb_alloc_page
3003 * @skb: The skb that may need pfmemalloc set
3005 static inline void skb_propagate_pfmemalloc(const struct page
*page
,
3006 struct sk_buff
*skb
)
3008 if (page_is_pfmemalloc(page
))
3009 skb
->pfmemalloc
= true;
3013 * skb_frag_off() - Returns the offset of a skb fragment
3014 * @frag: the paged fragment
3016 static inline unsigned int skb_frag_off(const skb_frag_t
*frag
)
3018 return frag
->bv_offset
;
3022 * skb_frag_off_add() - Increments the offset of a skb fragment by @delta
3023 * @frag: skb fragment
3024 * @delta: value to add
3026 static inline void skb_frag_off_add(skb_frag_t
*frag
, int delta
)
3028 frag
->bv_offset
+= delta
;
3032 * skb_frag_off_set() - Sets the offset of a skb fragment
3033 * @frag: skb fragment
3034 * @offset: offset of fragment
3036 static inline void skb_frag_off_set(skb_frag_t
*frag
, unsigned int offset
)
3038 frag
->bv_offset
= offset
;
3042 * skb_frag_off_copy() - Sets the offset of a skb fragment from another fragment
3043 * @fragto: skb fragment where offset is set
3044 * @fragfrom: skb fragment offset is copied from
3046 static inline void skb_frag_off_copy(skb_frag_t
*fragto
,
3047 const skb_frag_t
*fragfrom
)
3049 fragto
->bv_offset
= fragfrom
->bv_offset
;
3053 * skb_frag_page - retrieve the page referred to by a paged fragment
3054 * @frag: the paged fragment
3056 * Returns the &struct page associated with @frag.
3058 static inline struct page
*skb_frag_page(const skb_frag_t
*frag
)
3060 return frag
->bv_page
;
3064 * __skb_frag_ref - take an addition reference on a paged fragment.
3065 * @frag: the paged fragment
3067 * Takes an additional reference on the paged fragment @frag.
3069 static inline void __skb_frag_ref(skb_frag_t
*frag
)
3071 get_page(skb_frag_page(frag
));
3075 * skb_frag_ref - take an addition reference on a paged fragment of an skb.
3077 * @f: the fragment offset.
3079 * Takes an additional reference on the @f'th paged fragment of @skb.
3081 static inline void skb_frag_ref(struct sk_buff
*skb
, int f
)
3083 __skb_frag_ref(&skb_shinfo(skb
)->frags
[f
]);
3087 * __skb_frag_unref - release a reference on a paged fragment.
3088 * @frag: the paged fragment
3089 * @recycle: recycle the page if allocated via page_pool
3091 * Releases a reference on the paged fragment @frag
3092 * or recycles the page via the page_pool API.
3094 static inline void __skb_frag_unref(skb_frag_t
*frag
, bool recycle
)
3096 struct page
*page
= skb_frag_page(frag
);
3098 #ifdef CONFIG_PAGE_POOL
3099 if (recycle
&& page_pool_return_skb_page(page
))
3106 * skb_frag_unref - release a reference on a paged fragment of an skb.
3108 * @f: the fragment offset
3110 * Releases a reference on the @f'th paged fragment of @skb.
3112 static inline void skb_frag_unref(struct sk_buff
*skb
, int f
)
3114 __skb_frag_unref(&skb_shinfo(skb
)->frags
[f
], skb
->pp_recycle
);
3118 * skb_frag_address - gets the address of the data contained in a paged fragment
3119 * @frag: the paged fragment buffer
3121 * Returns the address of the data within @frag. The page must already
3124 static inline void *skb_frag_address(const skb_frag_t
*frag
)
3126 return page_address(skb_frag_page(frag
)) + skb_frag_off(frag
);
3130 * skb_frag_address_safe - gets the address of the data contained in a paged fragment
3131 * @frag: the paged fragment buffer
3133 * Returns the address of the data within @frag. Checks that the page
3134 * is mapped and returns %NULL otherwise.
3136 static inline void *skb_frag_address_safe(const skb_frag_t
*frag
)
3138 void *ptr
= page_address(skb_frag_page(frag
));
3142 return ptr
+ skb_frag_off(frag
);
3146 * skb_frag_page_copy() - sets the page in a fragment from another fragment
3147 * @fragto: skb fragment where page is set
3148 * @fragfrom: skb fragment page is copied from
3150 static inline void skb_frag_page_copy(skb_frag_t
*fragto
,
3151 const skb_frag_t
*fragfrom
)
3153 fragto
->bv_page
= fragfrom
->bv_page
;
3157 * __skb_frag_set_page - sets the page contained in a paged fragment
3158 * @frag: the paged fragment
3159 * @page: the page to set
3161 * Sets the fragment @frag to contain @page.
3163 static inline void __skb_frag_set_page(skb_frag_t
*frag
, struct page
*page
)
3165 frag
->bv_page
= page
;
3169 * skb_frag_set_page - sets the page contained in a paged fragment of an skb
3171 * @f: the fragment offset
3172 * @page: the page to set
3174 * Sets the @f'th fragment of @skb to contain @page.
3176 static inline void skb_frag_set_page(struct sk_buff
*skb
, int f
,
3179 __skb_frag_set_page(&skb_shinfo(skb
)->frags
[f
], page
);
3182 bool skb_page_frag_refill(unsigned int sz
, struct page_frag
*pfrag
, gfp_t prio
);
3185 * skb_frag_dma_map - maps a paged fragment via the DMA API
3186 * @dev: the device to map the fragment to
3187 * @frag: the paged fragment to map
3188 * @offset: the offset within the fragment (starting at the
3189 * fragment's own offset)
3190 * @size: the number of bytes to map
3191 * @dir: the direction of the mapping (``PCI_DMA_*``)
3193 * Maps the page associated with @frag to @device.
3195 static inline dma_addr_t
skb_frag_dma_map(struct device
*dev
,
3196 const skb_frag_t
*frag
,
3197 size_t offset
, size_t size
,
3198 enum dma_data_direction dir
)
3200 return dma_map_page(dev
, skb_frag_page(frag
),
3201 skb_frag_off(frag
) + offset
, size
, dir
);
3204 static inline struct sk_buff
*pskb_copy(struct sk_buff
*skb
,
3207 return __pskb_copy(skb
, skb_headroom(skb
), gfp_mask
);
3211 static inline struct sk_buff
*pskb_copy_for_clone(struct sk_buff
*skb
,
3214 return __pskb_copy_fclone(skb
, skb_headroom(skb
), gfp_mask
, true);
3219 * skb_clone_writable - is the header of a clone writable
3220 * @skb: buffer to check
3221 * @len: length up to which to write
3223 * Returns true if modifying the header part of the cloned buffer
3224 * does not requires the data to be copied.
3226 static inline int skb_clone_writable(const struct sk_buff
*skb
, unsigned int len
)
3228 return !skb_header_cloned(skb
) &&
3229 skb_headroom(skb
) + len
<= skb
->hdr_len
;
3232 static inline int skb_try_make_writable(struct sk_buff
*skb
,
3233 unsigned int write_len
)
3235 return skb_cloned(skb
) && !skb_clone_writable(skb
, write_len
) &&
3236 pskb_expand_head(skb
, 0, 0, GFP_ATOMIC
);
3239 static inline int __skb_cow(struct sk_buff
*skb
, unsigned int headroom
,
3244 if (headroom
> skb_headroom(skb
))
3245 delta
= headroom
- skb_headroom(skb
);
3247 if (delta
|| cloned
)
3248 return pskb_expand_head(skb
, ALIGN(delta
, NET_SKB_PAD
), 0,
3254 * skb_cow - copy header of skb when it is required
3255 * @skb: buffer to cow
3256 * @headroom: needed headroom
3258 * If the skb passed lacks sufficient headroom or its data part
3259 * is shared, data is reallocated. If reallocation fails, an error
3260 * is returned and original skb is not changed.
3262 * The result is skb with writable area skb->head...skb->tail
3263 * and at least @headroom of space at head.
3265 static inline int skb_cow(struct sk_buff
*skb
, unsigned int headroom
)
3267 return __skb_cow(skb
, headroom
, skb_cloned(skb
));
3271 * skb_cow_head - skb_cow but only making the head writable
3272 * @skb: buffer to cow
3273 * @headroom: needed headroom
3275 * This function is identical to skb_cow except that we replace the
3276 * skb_cloned check by skb_header_cloned. It should be used when
3277 * you only need to push on some header and do not need to modify
3280 static inline int skb_cow_head(struct sk_buff
*skb
, unsigned int headroom
)
3282 return __skb_cow(skb
, headroom
, skb_header_cloned(skb
));
3286 * skb_padto - pad an skbuff up to a minimal size
3287 * @skb: buffer to pad
3288 * @len: minimal length
3290 * Pads up a buffer to ensure the trailing bytes exist and are
3291 * blanked. If the buffer already contains sufficient data it
3292 * is untouched. Otherwise it is extended. Returns zero on
3293 * success. The skb is freed on error.
3295 static inline int skb_padto(struct sk_buff
*skb
, unsigned int len
)
3297 unsigned int size
= skb
->len
;
3298 if (likely(size
>= len
))
3300 return skb_pad(skb
, len
- size
);
3304 * __skb_put_padto - increase size and pad an skbuff up to a minimal size
3305 * @skb: buffer to pad
3306 * @len: minimal length
3307 * @free_on_error: free buffer on error
3309 * Pads up a buffer to ensure the trailing bytes exist and are
3310 * blanked. If the buffer already contains sufficient data it
3311 * is untouched. Otherwise it is extended. Returns zero on
3312 * success. The skb is freed on error if @free_on_error is true.
3314 static inline int __must_check
__skb_put_padto(struct sk_buff
*skb
,
3318 unsigned int size
= skb
->len
;
3320 if (unlikely(size
< len
)) {
3322 if (__skb_pad(skb
, len
, free_on_error
))
3324 __skb_put(skb
, len
);
3330 * skb_put_padto - increase size and pad an skbuff up to a minimal size
3331 * @skb: buffer to pad
3332 * @len: minimal length
3334 * Pads up a buffer to ensure the trailing bytes exist and are
3335 * blanked. If the buffer already contains sufficient data it
3336 * is untouched. Otherwise it is extended. Returns zero on
3337 * success. The skb is freed on error.
3339 static inline int __must_check
skb_put_padto(struct sk_buff
*skb
, unsigned int len
)
3341 return __skb_put_padto(skb
, len
, true);
3344 static inline int skb_add_data(struct sk_buff
*skb
,
3345 struct iov_iter
*from
, int copy
)
3347 const int off
= skb
->len
;
3349 if (skb
->ip_summed
== CHECKSUM_NONE
) {
3351 if (csum_and_copy_from_iter_full(skb_put(skb
, copy
), copy
,
3353 skb
->csum
= csum_block_add(skb
->csum
, csum
, off
);
3356 } else if (copy_from_iter_full(skb_put(skb
, copy
), copy
, from
))
3359 __skb_trim(skb
, off
);
3363 static inline bool skb_can_coalesce(struct sk_buff
*skb
, int i
,
3364 const struct page
*page
, int off
)
3369 const skb_frag_t
*frag
= &skb_shinfo(skb
)->frags
[i
- 1];
3371 return page
== skb_frag_page(frag
) &&
3372 off
== skb_frag_off(frag
) + skb_frag_size(frag
);
3377 static inline int __skb_linearize(struct sk_buff
*skb
)
3379 return __pskb_pull_tail(skb
, skb
->data_len
) ? 0 : -ENOMEM
;
3383 * skb_linearize - convert paged skb to linear one
3384 * @skb: buffer to linarize
3386 * If there is no free memory -ENOMEM is returned, otherwise zero
3387 * is returned and the old skb data released.
3389 static inline int skb_linearize(struct sk_buff
*skb
)
3391 return skb_is_nonlinear(skb
) ? __skb_linearize(skb
) : 0;
3395 * skb_has_shared_frag - can any frag be overwritten
3396 * @skb: buffer to test
3398 * Return true if the skb has at least one frag that might be modified
3399 * by an external entity (as in vmsplice()/sendfile())
3401 static inline bool skb_has_shared_frag(const struct sk_buff
*skb
)
3403 return skb_is_nonlinear(skb
) &&
3404 skb_shinfo(skb
)->flags
& SKBFL_SHARED_FRAG
;
3408 * skb_linearize_cow - make sure skb is linear and writable
3409 * @skb: buffer to process
3411 * If there is no free memory -ENOMEM is returned, otherwise zero
3412 * is returned and the old skb data released.
3414 static inline int skb_linearize_cow(struct sk_buff
*skb
)
3416 return skb_is_nonlinear(skb
) || skb_cloned(skb
) ?
3417 __skb_linearize(skb
) : 0;
3420 static __always_inline
void
3421 __skb_postpull_rcsum(struct sk_buff
*skb
, const void *start
, unsigned int len
,
3424 if (skb
->ip_summed
== CHECKSUM_COMPLETE
)
3425 skb
->csum
= csum_block_sub(skb
->csum
,
3426 csum_partial(start
, len
, 0), off
);
3427 else if (skb
->ip_summed
== CHECKSUM_PARTIAL
&&
3428 skb_checksum_start_offset(skb
) < 0)
3429 skb
->ip_summed
= CHECKSUM_NONE
;
3433 * skb_postpull_rcsum - update checksum for received skb after pull
3434 * @skb: buffer to update
3435 * @start: start of data before pull
3436 * @len: length of data pulled
3438 * After doing a pull on a received packet, you need to call this to
3439 * update the CHECKSUM_COMPLETE checksum, or set ip_summed to
3440 * CHECKSUM_NONE so that it can be recomputed from scratch.
3442 static inline void skb_postpull_rcsum(struct sk_buff
*skb
,
3443 const void *start
, unsigned int len
)
3445 __skb_postpull_rcsum(skb
, start
, len
, 0);
3448 static __always_inline
void
3449 __skb_postpush_rcsum(struct sk_buff
*skb
, const void *start
, unsigned int len
,
3452 if (skb
->ip_summed
== CHECKSUM_COMPLETE
)
3453 skb
->csum
= csum_block_add(skb
->csum
,
3454 csum_partial(start
, len
, 0), off
);
3458 * skb_postpush_rcsum - update checksum for received skb after push
3459 * @skb: buffer to update
3460 * @start: start of data after push
3461 * @len: length of data pushed
3463 * After doing a push on a received packet, you need to call this to
3464 * update the CHECKSUM_COMPLETE checksum.
3466 static inline void skb_postpush_rcsum(struct sk_buff
*skb
,
3467 const void *start
, unsigned int len
)
3469 __skb_postpush_rcsum(skb
, start
, len
, 0);
3472 void *skb_pull_rcsum(struct sk_buff
*skb
, unsigned int len
);
3475 * skb_push_rcsum - push skb and update receive checksum
3476 * @skb: buffer to update
3477 * @len: length of data pulled
3479 * This function performs an skb_push on the packet and updates
3480 * the CHECKSUM_COMPLETE checksum. It should be used on
3481 * receive path processing instead of skb_push unless you know
3482 * that the checksum difference is zero (e.g., a valid IP header)
3483 * or you are setting ip_summed to CHECKSUM_NONE.
3485 static inline void *skb_push_rcsum(struct sk_buff
*skb
, unsigned int len
)
3488 skb_postpush_rcsum(skb
, skb
->data
, len
);
3492 int pskb_trim_rcsum_slow(struct sk_buff
*skb
, unsigned int len
);
3494 * pskb_trim_rcsum - trim received skb and update checksum
3495 * @skb: buffer to trim
3498 * This is exactly the same as pskb_trim except that it ensures the
3499 * checksum of received packets are still valid after the operation.
3500 * It can change skb pointers.
3503 static inline int pskb_trim_rcsum(struct sk_buff
*skb
, unsigned int len
)
3505 if (likely(len
>= skb
->len
))
3507 return pskb_trim_rcsum_slow(skb
, len
);
3510 static inline int __skb_trim_rcsum(struct sk_buff
*skb
, unsigned int len
)
3512 if (skb
->ip_summed
== CHECKSUM_COMPLETE
)
3513 skb
->ip_summed
= CHECKSUM_NONE
;
3514 __skb_trim(skb
, len
);
3518 static inline int __skb_grow_rcsum(struct sk_buff
*skb
, unsigned int len
)
3520 if (skb
->ip_summed
== CHECKSUM_COMPLETE
)
3521 skb
->ip_summed
= CHECKSUM_NONE
;
3522 return __skb_grow(skb
, len
);
3525 #define rb_to_skb(rb) rb_entry_safe(rb, struct sk_buff, rbnode)
3526 #define skb_rb_first(root) rb_to_skb(rb_first(root))
3527 #define skb_rb_last(root) rb_to_skb(rb_last(root))
3528 #define skb_rb_next(skb) rb_to_skb(rb_next(&(skb)->rbnode))
3529 #define skb_rb_prev(skb) rb_to_skb(rb_prev(&(skb)->rbnode))
3531 #define skb_queue_walk(queue, skb) \
3532 for (skb = (queue)->next; \
3533 skb != (struct sk_buff *)(queue); \
3536 #define skb_queue_walk_safe(queue, skb, tmp) \
3537 for (skb = (queue)->next, tmp = skb->next; \
3538 skb != (struct sk_buff *)(queue); \
3539 skb = tmp, tmp = skb->next)
3541 #define skb_queue_walk_from(queue, skb) \
3542 for (; skb != (struct sk_buff *)(queue); \
3545 #define skb_rbtree_walk(skb, root) \
3546 for (skb = skb_rb_first(root); skb != NULL; \
3547 skb = skb_rb_next(skb))
3549 #define skb_rbtree_walk_from(skb) \
3550 for (; skb != NULL; \
3551 skb = skb_rb_next(skb))
3553 #define skb_rbtree_walk_from_safe(skb, tmp) \
3554 for (; tmp = skb ? skb_rb_next(skb) : NULL, (skb != NULL); \
3557 #define skb_queue_walk_from_safe(queue, skb, tmp) \
3558 for (tmp = skb->next; \
3559 skb != (struct sk_buff *)(queue); \
3560 skb = tmp, tmp = skb->next)
3562 #define skb_queue_reverse_walk(queue, skb) \
3563 for (skb = (queue)->prev; \
3564 skb != (struct sk_buff *)(queue); \
3567 #define skb_queue_reverse_walk_safe(queue, skb, tmp) \
3568 for (skb = (queue)->prev, tmp = skb->prev; \
3569 skb != (struct sk_buff *)(queue); \
3570 skb = tmp, tmp = skb->prev)
3572 #define skb_queue_reverse_walk_from_safe(queue, skb, tmp) \
3573 for (tmp = skb->prev; \
3574 skb != (struct sk_buff *)(queue); \
3575 skb = tmp, tmp = skb->prev)
3577 static inline bool skb_has_frag_list(const struct sk_buff
*skb
)
3579 return skb_shinfo(skb
)->frag_list
!= NULL
;
3582 static inline void skb_frag_list_init(struct sk_buff
*skb
)
3584 skb_shinfo(skb
)->frag_list
= NULL
;
3587 #define skb_walk_frags(skb, iter) \
3588 for (iter = skb_shinfo(skb)->frag_list; iter; iter = iter->next)
3591 int __skb_wait_for_more_packets(struct sock
*sk
, struct sk_buff_head
*queue
,
3592 int *err
, long *timeo_p
,
3593 const struct sk_buff
*skb
);
3594 struct sk_buff
*__skb_try_recv_from_queue(struct sock
*sk
,
3595 struct sk_buff_head
*queue
,
3598 struct sk_buff
**last
);
3599 struct sk_buff
*__skb_try_recv_datagram(struct sock
*sk
,
3600 struct sk_buff_head
*queue
,
3601 unsigned int flags
, int *off
, int *err
,
3602 struct sk_buff
**last
);
3603 struct sk_buff
*__skb_recv_datagram(struct sock
*sk
,
3604 struct sk_buff_head
*sk_queue
,
3605 unsigned int flags
, int *off
, int *err
);
3606 struct sk_buff
*skb_recv_datagram(struct sock
*sk
, unsigned flags
, int noblock
,
3608 __poll_t
datagram_poll(struct file
*file
, struct socket
*sock
,
3609 struct poll_table_struct
*wait
);
3610 int skb_copy_datagram_iter(const struct sk_buff
*from
, int offset
,
3611 struct iov_iter
*to
, int size
);
3612 static inline int skb_copy_datagram_msg(const struct sk_buff
*from
, int offset
,
3613 struct msghdr
*msg
, int size
)
3615 return skb_copy_datagram_iter(from
, offset
, &msg
->msg_iter
, size
);
3617 int skb_copy_and_csum_datagram_msg(struct sk_buff
*skb
, int hlen
,
3618 struct msghdr
*msg
);
3619 int skb_copy_and_hash_datagram_iter(const struct sk_buff
*skb
, int offset
,
3620 struct iov_iter
*to
, int len
,
3621 struct ahash_request
*hash
);
3622 int skb_copy_datagram_from_iter(struct sk_buff
*skb
, int offset
,
3623 struct iov_iter
*from
, int len
);
3624 int zerocopy_sg_from_iter(struct sk_buff
*skb
, struct iov_iter
*frm
);
3625 void skb_free_datagram(struct sock
*sk
, struct sk_buff
*skb
);
3626 void __skb_free_datagram_locked(struct sock
*sk
, struct sk_buff
*skb
, int len
);
3627 static inline void skb_free_datagram_locked(struct sock
*sk
,
3628 struct sk_buff
*skb
)
3630 __skb_free_datagram_locked(sk
, skb
, 0);
3632 int skb_kill_datagram(struct sock
*sk
, struct sk_buff
*skb
, unsigned int flags
);
3633 int skb_copy_bits(const struct sk_buff
*skb
, int offset
, void *to
, int len
);
3634 int skb_store_bits(struct sk_buff
*skb
, int offset
, const void *from
, int len
);
3635 __wsum
skb_copy_and_csum_bits(const struct sk_buff
*skb
, int offset
, u8
*to
,
3637 int skb_splice_bits(struct sk_buff
*skb
, struct sock
*sk
, unsigned int offset
,
3638 struct pipe_inode_info
*pipe
, unsigned int len
,
3639 unsigned int flags
);
3640 int skb_send_sock_locked(struct sock
*sk
, struct sk_buff
*skb
, int offset
,
3642 int skb_send_sock(struct sock
*sk
, struct sk_buff
*skb
, int offset
, int len
);
3643 void skb_copy_and_csum_dev(const struct sk_buff
*skb
, u8
*to
);
3644 unsigned int skb_zerocopy_headlen(const struct sk_buff
*from
);
3645 int skb_zerocopy(struct sk_buff
*to
, struct sk_buff
*from
,
3647 void skb_split(struct sk_buff
*skb
, struct sk_buff
*skb1
, const u32 len
);
3648 int skb_shift(struct sk_buff
*tgt
, struct sk_buff
*skb
, int shiftlen
);
3649 void skb_scrub_packet(struct sk_buff
*skb
, bool xnet
);
3650 bool skb_gso_validate_network_len(const struct sk_buff
*skb
, unsigned int mtu
);
3651 bool skb_gso_validate_mac_len(const struct sk_buff
*skb
, unsigned int len
);
3652 struct sk_buff
*skb_segment(struct sk_buff
*skb
, netdev_features_t features
);
3653 struct sk_buff
*skb_segment_list(struct sk_buff
*skb
, netdev_features_t features
,
3654 unsigned int offset
);
3655 struct sk_buff
*skb_vlan_untag(struct sk_buff
*skb
);
3656 int skb_ensure_writable(struct sk_buff
*skb
, int write_len
);
3657 int __skb_vlan_pop(struct sk_buff
*skb
, u16
*vlan_tci
);
3658 int skb_vlan_pop(struct sk_buff
*skb
);
3659 int skb_vlan_push(struct sk_buff
*skb
, __be16 vlan_proto
, u16 vlan_tci
);
3660 int skb_eth_pop(struct sk_buff
*skb
);
3661 int skb_eth_push(struct sk_buff
*skb
, const unsigned char *dst
,
3662 const unsigned char *src
);
3663 int skb_mpls_push(struct sk_buff
*skb
, __be32 mpls_lse
, __be16 mpls_proto
,
3664 int mac_len
, bool ethernet
);
3665 int skb_mpls_pop(struct sk_buff
*skb
, __be16 next_proto
, int mac_len
,
3667 int skb_mpls_update_lse(struct sk_buff
*skb
, __be32 mpls_lse
);
3668 int skb_mpls_dec_ttl(struct sk_buff
*skb
);
3669 struct sk_buff
*pskb_extract(struct sk_buff
*skb
, int off
, int to_copy
,
3672 static inline int memcpy_from_msg(void *data
, struct msghdr
*msg
, int len
)
3674 return copy_from_iter_full(data
, len
, &msg
->msg_iter
) ? 0 : -EFAULT
;
3677 static inline int memcpy_to_msg(struct msghdr
*msg
, void *data
, int len
)
3679 return copy_to_iter(data
, len
, &msg
->msg_iter
) == len
? 0 : -EFAULT
;
3682 struct skb_checksum_ops
{
3683 __wsum (*update
)(const void *mem
, int len
, __wsum wsum
);
3684 __wsum (*combine
)(__wsum csum
, __wsum csum2
, int offset
, int len
);
3687 extern const struct skb_checksum_ops
*crc32c_csum_stub __read_mostly
;
3689 __wsum
__skb_checksum(const struct sk_buff
*skb
, int offset
, int len
,
3690 __wsum csum
, const struct skb_checksum_ops
*ops
);
3691 __wsum
skb_checksum(const struct sk_buff
*skb
, int offset
, int len
,
3694 static inline void * __must_check
3695 __skb_header_pointer(const struct sk_buff
*skb
, int offset
, int len
,
3696 const void *data
, int hlen
, void *buffer
)
3698 if (likely(hlen
- offset
>= len
))
3699 return (void *)data
+ offset
;
3701 if (!skb
|| unlikely(skb_copy_bits(skb
, offset
, buffer
, len
) < 0))
3707 static inline void * __must_check
3708 skb_header_pointer(const struct sk_buff
*skb
, int offset
, int len
, void *buffer
)
3710 return __skb_header_pointer(skb
, offset
, len
, skb
->data
,
3711 skb_headlen(skb
), buffer
);
3715 * skb_needs_linearize - check if we need to linearize a given skb
3716 * depending on the given device features.
3717 * @skb: socket buffer to check
3718 * @features: net device features
3720 * Returns true if either:
3721 * 1. skb has frag_list and the device doesn't support FRAGLIST, or
3722 * 2. skb is fragmented and the device does not support SG.
3724 static inline bool skb_needs_linearize(struct sk_buff
*skb
,
3725 netdev_features_t features
)
3727 return skb_is_nonlinear(skb
) &&
3728 ((skb_has_frag_list(skb
) && !(features
& NETIF_F_FRAGLIST
)) ||
3729 (skb_shinfo(skb
)->nr_frags
&& !(features
& NETIF_F_SG
)));
3732 static inline void skb_copy_from_linear_data(const struct sk_buff
*skb
,
3734 const unsigned int len
)
3736 memcpy(to
, skb
->data
, len
);
3739 static inline void skb_copy_from_linear_data_offset(const struct sk_buff
*skb
,
3740 const int offset
, void *to
,
3741 const unsigned int len
)
3743 memcpy(to
, skb
->data
+ offset
, len
);
3746 static inline void skb_copy_to_linear_data(struct sk_buff
*skb
,
3748 const unsigned int len
)
3750 memcpy(skb
->data
, from
, len
);
3753 static inline void skb_copy_to_linear_data_offset(struct sk_buff
*skb
,
3756 const unsigned int len
)
3758 memcpy(skb
->data
+ offset
, from
, len
);
3761 void skb_init(void);
3763 static inline ktime_t
skb_get_ktime(const struct sk_buff
*skb
)
3769 * skb_get_timestamp - get timestamp from a skb
3770 * @skb: skb to get stamp from
3771 * @stamp: pointer to struct __kernel_old_timeval to store stamp in
3773 * Timestamps are stored in the skb as offsets to a base timestamp.
3774 * This function converts the offset back to a struct timeval and stores
3777 static inline void skb_get_timestamp(const struct sk_buff
*skb
,
3778 struct __kernel_old_timeval
*stamp
)
3780 *stamp
= ns_to_kernel_old_timeval(skb
->tstamp
);
3783 static inline void skb_get_new_timestamp(const struct sk_buff
*skb
,
3784 struct __kernel_sock_timeval
*stamp
)
3786 struct timespec64 ts
= ktime_to_timespec64(skb
->tstamp
);
3788 stamp
->tv_sec
= ts
.tv_sec
;
3789 stamp
->tv_usec
= ts
.tv_nsec
/ 1000;
3792 static inline void skb_get_timestampns(const struct sk_buff
*skb
,
3793 struct __kernel_old_timespec
*stamp
)
3795 struct timespec64 ts
= ktime_to_timespec64(skb
->tstamp
);
3797 stamp
->tv_sec
= ts
.tv_sec
;
3798 stamp
->tv_nsec
= ts
.tv_nsec
;
3801 static inline void skb_get_new_timestampns(const struct sk_buff
*skb
,
3802 struct __kernel_timespec
*stamp
)
3804 struct timespec64 ts
= ktime_to_timespec64(skb
->tstamp
);
3806 stamp
->tv_sec
= ts
.tv_sec
;
3807 stamp
->tv_nsec
= ts
.tv_nsec
;
3810 static inline void __net_timestamp(struct sk_buff
*skb
)
3812 skb
->tstamp
= ktime_get_real();
3815 static inline ktime_t
net_timedelta(ktime_t t
)
3817 return ktime_sub(ktime_get_real(), t
);
3820 static inline ktime_t
net_invalid_timestamp(void)
3825 static inline u8
skb_metadata_len(const struct sk_buff
*skb
)
3827 return skb_shinfo(skb
)->meta_len
;
3830 static inline void *skb_metadata_end(const struct sk_buff
*skb
)
3832 return skb_mac_header(skb
);
3835 static inline bool __skb_metadata_differs(const struct sk_buff
*skb_a
,
3836 const struct sk_buff
*skb_b
,
3839 const void *a
= skb_metadata_end(skb_a
);
3840 const void *b
= skb_metadata_end(skb_b
);
3841 /* Using more efficient varaiant than plain call to memcmp(). */
3842 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
3846 #define __it(x, op) (x -= sizeof(u##op))
3847 #define __it_diff(a, b, op) (*(u##op *)__it(a, op)) ^ (*(u##op *)__it(b, op))
3848 case 32: diffs
|= __it_diff(a
, b
, 64);
3850 case 24: diffs
|= __it_diff(a
, b
, 64);
3852 case 16: diffs
|= __it_diff(a
, b
, 64);
3854 case 8: diffs
|= __it_diff(a
, b
, 64);
3856 case 28: diffs
|= __it_diff(a
, b
, 64);
3858 case 20: diffs
|= __it_diff(a
, b
, 64);
3860 case 12: diffs
|= __it_diff(a
, b
, 64);
3862 case 4: diffs
|= __it_diff(a
, b
, 32);
3867 return memcmp(a
- meta_len
, b
- meta_len
, meta_len
);
3871 static inline bool skb_metadata_differs(const struct sk_buff
*skb_a
,
3872 const struct sk_buff
*skb_b
)
3874 u8 len_a
= skb_metadata_len(skb_a
);
3875 u8 len_b
= skb_metadata_len(skb_b
);
3877 if (!(len_a
| len_b
))
3880 return len_a
!= len_b
?
3881 true : __skb_metadata_differs(skb_a
, skb_b
, len_a
);
3884 static inline void skb_metadata_set(struct sk_buff
*skb
, u8 meta_len
)
3886 skb_shinfo(skb
)->meta_len
= meta_len
;
3889 static inline void skb_metadata_clear(struct sk_buff
*skb
)
3891 skb_metadata_set(skb
, 0);
3894 struct sk_buff
*skb_clone_sk(struct sk_buff
*skb
);
3896 #ifdef CONFIG_NETWORK_PHY_TIMESTAMPING
3898 void skb_clone_tx_timestamp(struct sk_buff
*skb
);
3899 bool skb_defer_rx_timestamp(struct sk_buff
*skb
);
3901 #else /* CONFIG_NETWORK_PHY_TIMESTAMPING */
3903 static inline void skb_clone_tx_timestamp(struct sk_buff
*skb
)
3907 static inline bool skb_defer_rx_timestamp(struct sk_buff
*skb
)
3912 #endif /* !CONFIG_NETWORK_PHY_TIMESTAMPING */
3915 * skb_complete_tx_timestamp() - deliver cloned skb with tx timestamps
3917 * PHY drivers may accept clones of transmitted packets for
3918 * timestamping via their phy_driver.txtstamp method. These drivers
3919 * must call this function to return the skb back to the stack with a
3922 * @skb: clone of the original outgoing packet
3923 * @hwtstamps: hardware time stamps
3926 void skb_complete_tx_timestamp(struct sk_buff
*skb
,
3927 struct skb_shared_hwtstamps
*hwtstamps
);
3929 void __skb_tstamp_tx(struct sk_buff
*orig_skb
, const struct sk_buff
*ack_skb
,
3930 struct skb_shared_hwtstamps
*hwtstamps
,
3931 struct sock
*sk
, int tstype
);
3934 * skb_tstamp_tx - queue clone of skb with send time stamps
3935 * @orig_skb: the original outgoing packet
3936 * @hwtstamps: hardware time stamps, may be NULL if not available
3938 * If the skb has a socket associated, then this function clones the
3939 * skb (thus sharing the actual data and optional structures), stores
3940 * the optional hardware time stamping information (if non NULL) or
3941 * generates a software time stamp (otherwise), then queues the clone
3942 * to the error queue of the socket. Errors are silently ignored.
3944 void skb_tstamp_tx(struct sk_buff
*orig_skb
,
3945 struct skb_shared_hwtstamps
*hwtstamps
);
3948 * skb_tx_timestamp() - Driver hook for transmit timestamping
3950 * Ethernet MAC Drivers should call this function in their hard_xmit()
3951 * function immediately before giving the sk_buff to the MAC hardware.
3953 * Specifically, one should make absolutely sure that this function is
3954 * called before TX completion of this packet can trigger. Otherwise
3955 * the packet could potentially already be freed.
3957 * @skb: A socket buffer.
3959 static inline void skb_tx_timestamp(struct sk_buff
*skb
)
3961 skb_clone_tx_timestamp(skb
);
3962 if (skb_shinfo(skb
)->tx_flags
& SKBTX_SW_TSTAMP
)
3963 skb_tstamp_tx(skb
, NULL
);
3967 * skb_complete_wifi_ack - deliver skb with wifi status
3969 * @skb: the original outgoing packet
3970 * @acked: ack status
3973 void skb_complete_wifi_ack(struct sk_buff
*skb
, bool acked
);
3975 __sum16
__skb_checksum_complete_head(struct sk_buff
*skb
, int len
);
3976 __sum16
__skb_checksum_complete(struct sk_buff
*skb
);
3978 static inline int skb_csum_unnecessary(const struct sk_buff
*skb
)
3980 return ((skb
->ip_summed
== CHECKSUM_UNNECESSARY
) ||
3982 (skb
->ip_summed
== CHECKSUM_PARTIAL
&&
3983 skb_checksum_start_offset(skb
) >= 0));
3987 * skb_checksum_complete - Calculate checksum of an entire packet
3988 * @skb: packet to process
3990 * This function calculates the checksum over the entire packet plus
3991 * the value of skb->csum. The latter can be used to supply the
3992 * checksum of a pseudo header as used by TCP/UDP. It returns the
3995 * For protocols that contain complete checksums such as ICMP/TCP/UDP,
3996 * this function can be used to verify that checksum on received
3997 * packets. In that case the function should return zero if the
3998 * checksum is correct. In particular, this function will return zero
3999 * if skb->ip_summed is CHECKSUM_UNNECESSARY which indicates that the
4000 * hardware has already verified the correctness of the checksum.
4002 static inline __sum16
skb_checksum_complete(struct sk_buff
*skb
)
4004 return skb_csum_unnecessary(skb
) ?
4005 0 : __skb_checksum_complete(skb
);
4008 static inline void __skb_decr_checksum_unnecessary(struct sk_buff
*skb
)
4010 if (skb
->ip_summed
== CHECKSUM_UNNECESSARY
) {
4011 if (skb
->csum_level
== 0)
4012 skb
->ip_summed
= CHECKSUM_NONE
;
4018 static inline void __skb_incr_checksum_unnecessary(struct sk_buff
*skb
)
4020 if (skb
->ip_summed
== CHECKSUM_UNNECESSARY
) {
4021 if (skb
->csum_level
< SKB_MAX_CSUM_LEVEL
)
4023 } else if (skb
->ip_summed
== CHECKSUM_NONE
) {
4024 skb
->ip_summed
= CHECKSUM_UNNECESSARY
;
4025 skb
->csum_level
= 0;
4029 static inline void __skb_reset_checksum_unnecessary(struct sk_buff
*skb
)
4031 if (skb
->ip_summed
== CHECKSUM_UNNECESSARY
) {
4032 skb
->ip_summed
= CHECKSUM_NONE
;
4033 skb
->csum_level
= 0;
4037 /* Check if we need to perform checksum complete validation.
4039 * Returns true if checksum complete is needed, false otherwise
4040 * (either checksum is unnecessary or zero checksum is allowed).
4042 static inline bool __skb_checksum_validate_needed(struct sk_buff
*skb
,
4046 if (skb_csum_unnecessary(skb
) || (zero_okay
&& !check
)) {
4047 skb
->csum_valid
= 1;
4048 __skb_decr_checksum_unnecessary(skb
);
4055 /* For small packets <= CHECKSUM_BREAK perform checksum complete directly
4058 #define CHECKSUM_BREAK 76
4060 /* Unset checksum-complete
4062 * Unset checksum complete can be done when packet is being modified
4063 * (uncompressed for instance) and checksum-complete value is
4066 static inline void skb_checksum_complete_unset(struct sk_buff
*skb
)
4068 if (skb
->ip_summed
== CHECKSUM_COMPLETE
)
4069 skb
->ip_summed
= CHECKSUM_NONE
;
4072 /* Validate (init) checksum based on checksum complete.
4075 * 0: checksum is validated or try to in skb_checksum_complete. In the latter
4076 * case the ip_summed will not be CHECKSUM_UNNECESSARY and the pseudo
4077 * checksum is stored in skb->csum for use in __skb_checksum_complete
4078 * non-zero: value of invalid checksum
4081 static inline __sum16
__skb_checksum_validate_complete(struct sk_buff
*skb
,
4085 if (skb
->ip_summed
== CHECKSUM_COMPLETE
) {
4086 if (!csum_fold(csum_add(psum
, skb
->csum
))) {
4087 skb
->csum_valid
= 1;
4094 if (complete
|| skb
->len
<= CHECKSUM_BREAK
) {
4097 csum
= __skb_checksum_complete(skb
);
4098 skb
->csum_valid
= !csum
;
4105 static inline __wsum
null_compute_pseudo(struct sk_buff
*skb
, int proto
)
4110 /* Perform checksum validate (init). Note that this is a macro since we only
4111 * want to calculate the pseudo header which is an input function if necessary.
4112 * First we try to validate without any computation (checksum unnecessary) and
4113 * then calculate based on checksum complete calling the function to compute
4117 * 0: checksum is validated or try to in skb_checksum_complete
4118 * non-zero: value of invalid checksum
4120 #define __skb_checksum_validate(skb, proto, complete, \
4121 zero_okay, check, compute_pseudo) \
4123 __sum16 __ret = 0; \
4124 skb->csum_valid = 0; \
4125 if (__skb_checksum_validate_needed(skb, zero_okay, check)) \
4126 __ret = __skb_checksum_validate_complete(skb, \
4127 complete, compute_pseudo(skb, proto)); \
4131 #define skb_checksum_init(skb, proto, compute_pseudo) \
4132 __skb_checksum_validate(skb, proto, false, false, 0, compute_pseudo)
4134 #define skb_checksum_init_zero_check(skb, proto, check, compute_pseudo) \
4135 __skb_checksum_validate(skb, proto, false, true, check, compute_pseudo)
4137 #define skb_checksum_validate(skb, proto, compute_pseudo) \
4138 __skb_checksum_validate(skb, proto, true, false, 0, compute_pseudo)
4140 #define skb_checksum_validate_zero_check(skb, proto, check, \
4142 __skb_checksum_validate(skb, proto, true, true, check, compute_pseudo)
4144 #define skb_checksum_simple_validate(skb) \
4145 __skb_checksum_validate(skb, 0, true, false, 0, null_compute_pseudo)
4147 static inline bool __skb_checksum_convert_check(struct sk_buff
*skb
)
4149 return (skb
->ip_summed
== CHECKSUM_NONE
&& skb
->csum_valid
);
4152 static inline void __skb_checksum_convert(struct sk_buff
*skb
, __wsum pseudo
)
4154 skb
->csum
= ~pseudo
;
4155 skb
->ip_summed
= CHECKSUM_COMPLETE
;
4158 #define skb_checksum_try_convert(skb, proto, compute_pseudo) \
4160 if (__skb_checksum_convert_check(skb)) \
4161 __skb_checksum_convert(skb, compute_pseudo(skb, proto)); \
4164 static inline void skb_remcsum_adjust_partial(struct sk_buff
*skb
, void *ptr
,
4165 u16 start
, u16 offset
)
4167 skb
->ip_summed
= CHECKSUM_PARTIAL
;
4168 skb
->csum_start
= ((unsigned char *)ptr
+ start
) - skb
->head
;
4169 skb
->csum_offset
= offset
- start
;
4172 /* Update skbuf and packet to reflect the remote checksum offload operation.
4173 * When called, ptr indicates the starting point for skb->csum when
4174 * ip_summed is CHECKSUM_COMPLETE. If we need create checksum complete
4175 * here, skb_postpull_rcsum is done so skb->csum start is ptr.
4177 static inline void skb_remcsum_process(struct sk_buff
*skb
, void *ptr
,
4178 int start
, int offset
, bool nopartial
)
4183 skb_remcsum_adjust_partial(skb
, ptr
, start
, offset
);
4187 if (unlikely(skb
->ip_summed
!= CHECKSUM_COMPLETE
)) {
4188 __skb_checksum_complete(skb
);
4189 skb_postpull_rcsum(skb
, skb
->data
, ptr
- (void *)skb
->data
);
4192 delta
= remcsum_adjust(ptr
, skb
->csum
, start
, offset
);
4194 /* Adjust skb->csum since we changed the packet */
4195 skb
->csum
= csum_add(skb
->csum
, delta
);
4198 static inline struct nf_conntrack
*skb_nfct(const struct sk_buff
*skb
)
4200 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
4201 return (void *)(skb
->_nfct
& NFCT_PTRMASK
);
4207 static inline unsigned long skb_get_nfct(const struct sk_buff
*skb
)
4209 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
4216 static inline void skb_set_nfct(struct sk_buff
*skb
, unsigned long nfct
)
4218 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
4223 #ifdef CONFIG_SKB_EXTENSIONS
4225 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
4231 #if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
4234 #if IS_ENABLED(CONFIG_MPTCP)
4237 SKB_EXT_NUM
, /* must be last */
4241 * struct skb_ext - sk_buff extensions
4242 * @refcnt: 1 on allocation, deallocated on 0
4243 * @offset: offset to add to @data to obtain extension address
4244 * @chunks: size currently allocated, stored in SKB_EXT_ALIGN_SHIFT units
4245 * @data: start of extension data, variable sized
4247 * Note: offsets/lengths are stored in chunks of 8 bytes, this allows
4248 * to use 'u8' types while allowing up to 2kb worth of extension data.
4252 u8 offset
[SKB_EXT_NUM
]; /* in chunks of 8 bytes */
4253 u8 chunks
; /* same */
4254 char data
[] __aligned(8);
4257 struct skb_ext
*__skb_ext_alloc(gfp_t flags
);
4258 void *__skb_ext_set(struct sk_buff
*skb
, enum skb_ext_id id
,
4259 struct skb_ext
*ext
);
4260 void *skb_ext_add(struct sk_buff
*skb
, enum skb_ext_id id
);
4261 void __skb_ext_del(struct sk_buff
*skb
, enum skb_ext_id id
);
4262 void __skb_ext_put(struct skb_ext
*ext
);
4264 static inline void skb_ext_put(struct sk_buff
*skb
)
4266 if (skb
->active_extensions
)
4267 __skb_ext_put(skb
->extensions
);
4270 static inline void __skb_ext_copy(struct sk_buff
*dst
,
4271 const struct sk_buff
*src
)
4273 dst
->active_extensions
= src
->active_extensions
;
4275 if (src
->active_extensions
) {
4276 struct skb_ext
*ext
= src
->extensions
;
4278 refcount_inc(&ext
->refcnt
);
4279 dst
->extensions
= ext
;
4283 static inline void skb_ext_copy(struct sk_buff
*dst
, const struct sk_buff
*src
)
4286 __skb_ext_copy(dst
, src
);
4289 static inline bool __skb_ext_exist(const struct skb_ext
*ext
, enum skb_ext_id i
)
4291 return !!ext
->offset
[i
];
4294 static inline bool skb_ext_exist(const struct sk_buff
*skb
, enum skb_ext_id id
)
4296 return skb
->active_extensions
& (1 << id
);
4299 static inline void skb_ext_del(struct sk_buff
*skb
, enum skb_ext_id id
)
4301 if (skb_ext_exist(skb
, id
))
4302 __skb_ext_del(skb
, id
);
4305 static inline void *skb_ext_find(const struct sk_buff
*skb
, enum skb_ext_id id
)
4307 if (skb_ext_exist(skb
, id
)) {
4308 struct skb_ext
*ext
= skb
->extensions
;
4310 return (void *)ext
+ (ext
->offset
[id
] << 3);
4316 static inline void skb_ext_reset(struct sk_buff
*skb
)
4318 if (unlikely(skb
->active_extensions
)) {
4319 __skb_ext_put(skb
->extensions
);
4320 skb
->active_extensions
= 0;
4324 static inline bool skb_has_extensions(struct sk_buff
*skb
)
4326 return unlikely(skb
->active_extensions
);
4329 static inline void skb_ext_put(struct sk_buff
*skb
) {}
4330 static inline void skb_ext_reset(struct sk_buff
*skb
) {}
4331 static inline void skb_ext_del(struct sk_buff
*skb
, int unused
) {}
4332 static inline void __skb_ext_copy(struct sk_buff
*d
, const struct sk_buff
*s
) {}
4333 static inline void skb_ext_copy(struct sk_buff
*dst
, const struct sk_buff
*s
) {}
4334 static inline bool skb_has_extensions(struct sk_buff
*skb
) { return false; }
4335 #endif /* CONFIG_SKB_EXTENSIONS */
4337 static inline void nf_reset_ct(struct sk_buff
*skb
)
4339 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
4340 nf_conntrack_put(skb_nfct(skb
));
4345 static inline void nf_reset_trace(struct sk_buff
*skb
)
4347 #if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE) || defined(CONFIG_NF_TABLES)
4352 static inline void ipvs_reset(struct sk_buff
*skb
)
4354 #if IS_ENABLED(CONFIG_IP_VS)
4355 skb
->ipvs_property
= 0;
4359 /* Note: This doesn't put any conntrack info in dst. */
4360 static inline void __nf_copy(struct sk_buff
*dst
, const struct sk_buff
*src
,
4363 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
4364 dst
->_nfct
= src
->_nfct
;
4365 nf_conntrack_get(skb_nfct(src
));
4367 #if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE) || defined(CONFIG_NF_TABLES)
4369 dst
->nf_trace
= src
->nf_trace
;
4373 static inline void nf_copy(struct sk_buff
*dst
, const struct sk_buff
*src
)
4375 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
4376 nf_conntrack_put(skb_nfct(dst
));
4378 __nf_copy(dst
, src
, true);
4381 #ifdef CONFIG_NETWORK_SECMARK
4382 static inline void skb_copy_secmark(struct sk_buff
*to
, const struct sk_buff
*from
)
4384 to
->secmark
= from
->secmark
;
4387 static inline void skb_init_secmark(struct sk_buff
*skb
)
4392 static inline void skb_copy_secmark(struct sk_buff
*to
, const struct sk_buff
*from
)
4395 static inline void skb_init_secmark(struct sk_buff
*skb
)
4399 static inline int secpath_exists(const struct sk_buff
*skb
)
4402 return skb_ext_exist(skb
, SKB_EXT_SEC_PATH
);
4408 static inline bool skb_irq_freeable(const struct sk_buff
*skb
)
4410 return !skb
->destructor
&&
4411 !secpath_exists(skb
) &&
4413 !skb
->_skb_refdst
&&
4414 !skb_has_frag_list(skb
);
4417 static inline void skb_set_queue_mapping(struct sk_buff
*skb
, u16 queue_mapping
)
4419 skb
->queue_mapping
= queue_mapping
;
4422 static inline u16
skb_get_queue_mapping(const struct sk_buff
*skb
)
4424 return skb
->queue_mapping
;
4427 static inline void skb_copy_queue_mapping(struct sk_buff
*to
, const struct sk_buff
*from
)
4429 to
->queue_mapping
= from
->queue_mapping
;
4432 static inline void skb_record_rx_queue(struct sk_buff
*skb
, u16 rx_queue
)
4434 skb
->queue_mapping
= rx_queue
+ 1;
4437 static inline u16
skb_get_rx_queue(const struct sk_buff
*skb
)
4439 return skb
->queue_mapping
- 1;
4442 static inline bool skb_rx_queue_recorded(const struct sk_buff
*skb
)
4444 return skb
->queue_mapping
!= 0;
4447 static inline void skb_set_dst_pending_confirm(struct sk_buff
*skb
, u32 val
)
4449 skb
->dst_pending_confirm
= val
;
4452 static inline bool skb_get_dst_pending_confirm(const struct sk_buff
*skb
)
4454 return skb
->dst_pending_confirm
!= 0;
4457 static inline struct sec_path
*skb_sec_path(const struct sk_buff
*skb
)
4460 return skb_ext_find(skb
, SKB_EXT_SEC_PATH
);
4466 /* Keeps track of mac header offset relative to skb->head.
4467 * It is useful for TSO of Tunneling protocol. e.g. GRE.
4468 * For non-tunnel skb it points to skb_mac_header() and for
4469 * tunnel skb it points to outer mac header.
4470 * Keeps track of level of encapsulation of network headers.
4481 #define SKB_GSO_CB_OFFSET 32
4482 #define SKB_GSO_CB(skb) ((struct skb_gso_cb *)((skb)->cb + SKB_GSO_CB_OFFSET))
4484 static inline int skb_tnl_header_len(const struct sk_buff
*inner_skb
)
4486 return (skb_mac_header(inner_skb
) - inner_skb
->head
) -
4487 SKB_GSO_CB(inner_skb
)->mac_offset
;
4490 static inline int gso_pskb_expand_head(struct sk_buff
*skb
, int extra
)
4492 int new_headroom
, headroom
;
4495 headroom
= skb_headroom(skb
);
4496 ret
= pskb_expand_head(skb
, extra
, 0, GFP_ATOMIC
);
4500 new_headroom
= skb_headroom(skb
);
4501 SKB_GSO_CB(skb
)->mac_offset
+= (new_headroom
- headroom
);
4505 static inline void gso_reset_checksum(struct sk_buff
*skb
, __wsum res
)
4507 /* Do not update partial checksums if remote checksum is enabled. */
4508 if (skb
->remcsum_offload
)
4511 SKB_GSO_CB(skb
)->csum
= res
;
4512 SKB_GSO_CB(skb
)->csum_start
= skb_checksum_start(skb
) - skb
->head
;
4515 /* Compute the checksum for a gso segment. First compute the checksum value
4516 * from the start of transport header to SKB_GSO_CB(skb)->csum_start, and
4517 * then add in skb->csum (checksum from csum_start to end of packet).
4518 * skb->csum and csum_start are then updated to reflect the checksum of the
4519 * resultant packet starting from the transport header-- the resultant checksum
4520 * is in the res argument (i.e. normally zero or ~ of checksum of a pseudo
4523 static inline __sum16
gso_make_checksum(struct sk_buff
*skb
, __wsum res
)
4525 unsigned char *csum_start
= skb_transport_header(skb
);
4526 int plen
= (skb
->head
+ SKB_GSO_CB(skb
)->csum_start
) - csum_start
;
4527 __wsum partial
= SKB_GSO_CB(skb
)->csum
;
4529 SKB_GSO_CB(skb
)->csum
= res
;
4530 SKB_GSO_CB(skb
)->csum_start
= csum_start
- skb
->head
;
4532 return csum_fold(csum_partial(csum_start
, plen
, partial
));
4535 static inline bool skb_is_gso(const struct sk_buff
*skb
)
4537 return skb_shinfo(skb
)->gso_size
;
4540 /* Note: Should be called only if skb_is_gso(skb) is true */
4541 static inline bool skb_is_gso_v6(const struct sk_buff
*skb
)
4543 return skb_shinfo(skb
)->gso_type
& SKB_GSO_TCPV6
;
4546 /* Note: Should be called only if skb_is_gso(skb) is true */
4547 static inline bool skb_is_gso_sctp(const struct sk_buff
*skb
)
4549 return skb_shinfo(skb
)->gso_type
& SKB_GSO_SCTP
;
4552 /* Note: Should be called only if skb_is_gso(skb) is true */
4553 static inline bool skb_is_gso_tcp(const struct sk_buff
*skb
)
4555 return skb_shinfo(skb
)->gso_type
& (SKB_GSO_TCPV4
| SKB_GSO_TCPV6
);
4558 static inline void skb_gso_reset(struct sk_buff
*skb
)
4560 skb_shinfo(skb
)->gso_size
= 0;
4561 skb_shinfo(skb
)->gso_segs
= 0;
4562 skb_shinfo(skb
)->gso_type
= 0;
4565 static inline void skb_increase_gso_size(struct skb_shared_info
*shinfo
,
4568 if (WARN_ON_ONCE(shinfo
->gso_size
== GSO_BY_FRAGS
))
4570 shinfo
->gso_size
+= increment
;
4573 static inline void skb_decrease_gso_size(struct skb_shared_info
*shinfo
,
4576 if (WARN_ON_ONCE(shinfo
->gso_size
== GSO_BY_FRAGS
))
4578 shinfo
->gso_size
-= decrement
;
4581 void __skb_warn_lro_forwarding(const struct sk_buff
*skb
);
4583 static inline bool skb_warn_if_lro(const struct sk_buff
*skb
)
4585 /* LRO sets gso_size but not gso_type, whereas if GSO is really
4586 * wanted then gso_type will be set. */
4587 const struct skb_shared_info
*shinfo
= skb_shinfo(skb
);
4589 if (skb_is_nonlinear(skb
) && shinfo
->gso_size
!= 0 &&
4590 unlikely(shinfo
->gso_type
== 0)) {
4591 __skb_warn_lro_forwarding(skb
);
4597 static inline void skb_forward_csum(struct sk_buff
*skb
)
4599 /* Unfortunately we don't support this one. Any brave souls? */
4600 if (skb
->ip_summed
== CHECKSUM_COMPLETE
)
4601 skb
->ip_summed
= CHECKSUM_NONE
;
4605 * skb_checksum_none_assert - make sure skb ip_summed is CHECKSUM_NONE
4606 * @skb: skb to check
4608 * fresh skbs have their ip_summed set to CHECKSUM_NONE.
4609 * Instead of forcing ip_summed to CHECKSUM_NONE, we can
4610 * use this helper, to document places where we make this assertion.
4612 static inline void skb_checksum_none_assert(const struct sk_buff
*skb
)
4615 BUG_ON(skb
->ip_summed
!= CHECKSUM_NONE
);
4619 bool skb_partial_csum_set(struct sk_buff
*skb
, u16 start
, u16 off
);
4621 int skb_checksum_setup(struct sk_buff
*skb
, bool recalculate
);
4622 struct sk_buff
*skb_checksum_trimmed(struct sk_buff
*skb
,
4623 unsigned int transport_len
,
4624 __sum16(*skb_chkf
)(struct sk_buff
*skb
));
4627 * skb_head_is_locked - Determine if the skb->head is locked down
4628 * @skb: skb to check
4630 * The head on skbs build around a head frag can be removed if they are
4631 * not cloned. This function returns true if the skb head is locked down
4632 * due to either being allocated via kmalloc, or by being a clone with
4633 * multiple references to the head.
4635 static inline bool skb_head_is_locked(const struct sk_buff
*skb
)
4637 return !skb
->head_frag
|| skb_cloned(skb
);
4640 /* Local Checksum Offload.
4641 * Compute outer checksum based on the assumption that the
4642 * inner checksum will be offloaded later.
4643 * See Documentation/networking/checksum-offloads.rst for
4644 * explanation of how this works.
4645 * Fill in outer checksum adjustment (e.g. with sum of outer
4646 * pseudo-header) before calling.
4647 * Also ensure that inner checksum is in linear data area.
4649 static inline __wsum
lco_csum(struct sk_buff
*skb
)
4651 unsigned char *csum_start
= skb_checksum_start(skb
);
4652 unsigned char *l4_hdr
= skb_transport_header(skb
);
4655 /* Start with complement of inner checksum adjustment */
4656 partial
= ~csum_unfold(*(__force __sum16
*)(csum_start
+
4659 /* Add in checksum of our headers (incl. outer checksum
4660 * adjustment filled in by caller) and return result.
4662 return csum_partial(l4_hdr
, csum_start
- l4_hdr
, partial
);
4665 static inline bool skb_is_redirected(const struct sk_buff
*skb
)
4667 #ifdef CONFIG_NET_REDIRECT
4668 return skb
->redirected
;
4674 static inline void skb_set_redirected(struct sk_buff
*skb
, bool from_ingress
)
4676 #ifdef CONFIG_NET_REDIRECT
4677 skb
->redirected
= 1;
4678 skb
->from_ingress
= from_ingress
;
4679 if (skb
->from_ingress
)
4684 static inline void skb_reset_redirect(struct sk_buff
*skb
)
4686 #ifdef CONFIG_NET_REDIRECT
4687 skb
->redirected
= 0;
4691 static inline bool skb_csum_is_sctp(struct sk_buff
*skb
)
4693 return skb
->csum_not_inet
;
4696 static inline void skb_set_kcov_handle(struct sk_buff
*skb
,
4697 const u64 kcov_handle
)
4700 skb
->kcov_handle
= kcov_handle
;
4704 static inline u64
skb_get_kcov_handle(struct sk_buff
*skb
)
4707 return skb
->kcov_handle
;
4713 #ifdef CONFIG_PAGE_POOL
4714 static inline void skb_mark_for_recycle(struct sk_buff
*skb
, struct page
*page
,
4715 struct page_pool
*pp
)
4717 skb
->pp_recycle
= 1;
4718 page_pool_store_mem_info(page
, pp
);
4722 static inline bool skb_pp_recycle(struct sk_buff
*skb
, void *data
)
4724 if (!IS_ENABLED(CONFIG_PAGE_POOL
) || !skb
->pp_recycle
)
4726 return page_pool_return_skb_page(virt_to_page(data
));
4729 #endif /* __KERNEL__ */
4730 #endif /* _LINUX_SKBUFF_H */