| /* |
| * Definitions for the 'struct sk_buff' memory handlers. |
| * |
| * Authors: |
| * Alan Cox, <gw4pts@gw4pts.ampr.org> |
| * Florian La Roche, <rzsfl@rz.uni-sb.de> |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation; either version |
| * 2 of the License, or (at your option) any later version. |
| */ |
| |
| #ifndef _LINUX_SKBUFF_H |
| #define _LINUX_SKBUFF_H |
| |
| #include <linux/kernel.h> |
| #include <linux/kmemcheck.h> |
| #include <linux/compiler.h> |
| #include <linux/time.h> |
| #include <linux/bug.h> |
| #include <linux/cache.h> |
| #include <linux/rbtree.h> |
| #include <linux/socket.h> |
| #include <linux/refcount.h> |
| |
| #include <linux/atomic.h> |
| #include <asm/types.h> |
| #include <linux/spinlock.h> |
| #include <linux/net.h> |
| #include <linux/textsearch.h> |
| #include <net/checksum.h> |
| #include <linux/rcupdate.h> |
| #include <linux/hrtimer.h> |
| #include <linux/dma-mapping.h> |
| #include <linux/netdev_features.h> |
| #include <linux/sched.h> |
| #include <linux/sched/clock.h> |
| #include <net/flow_dissector.h> |
| #include <linux/splice.h> |
| #include <linux/in6.h> |
| #include <linux/if_packet.h> |
| #include <net/flow.h> |
| |
| /* The interface for checksum offload between the stack and networking drivers |
| * is as follows... |
| * |
| * A. IP checksum related features |
| * |
| * Drivers advertise checksum offload capabilities in the features of a device. |
| * From the stack's point of view these are capabilities offered by the driver, |
| * a driver typically only advertises features that it is capable of offloading |
| * to its device. |
| * |
| * The checksum related features are: |
| * |
| * NETIF_F_HW_CSUM - The driver (or its device) is able to compute one |
| * IP (one's complement) checksum for any combination |
| * of protocols or protocol layering. The checksum is |
| * computed and set in a packet per the CHECKSUM_PARTIAL |
| * interface (see below). |
| * |
| * NETIF_F_IP_CSUM - Driver (device) is only able to checksum plain |
| * TCP or UDP packets over IPv4. These are specifically |
| * unencapsulated packets of the form IPv4|TCP or |
| * IPv4|UDP where the Protocol field in the IPv4 header |
| * is TCP or UDP. The IPv4 header may contain IP options |
| * This feature cannot be set in features for a device |
| * with NETIF_F_HW_CSUM also set. This feature is being |
| * DEPRECATED (see below). |
| * |
| * NETIF_F_IPV6_CSUM - Driver (device) is only able to checksum plain |
| * TCP or UDP packets over IPv6. These are specifically |
| * unencapsulated packets of the form IPv6|TCP or |
| * IPv4|UDP where the Next Header field in the IPv6 |
| * header is either TCP or UDP. IPv6 extension headers |
| * are not supported with this feature. This feature |
| * cannot be set in features for a device with |
| * NETIF_F_HW_CSUM also set. This feature is being |
| * DEPRECATED (see below). |
| * |
| * NETIF_F_RXCSUM - Driver (device) performs receive checksum offload. |
| * This flag is used only used to disable the RX checksum |
| * feature for a device. The stack will accept receive |
| * checksum indication in packets received on a device |
| * regardless of whether NETIF_F_RXCSUM is set. |
| * |
| * B. Checksumming of received packets by device. Indication of checksum |
| * verification is in set skb->ip_summed. Possible values are: |
| * |
| * CHECKSUM_NONE: |
| * |
| * Device did not checksum this packet e.g. due to lack of capabilities. |
| * The packet contains full (though not verified) checksum in packet but |
| * not in skb->csum. Thus, skb->csum is undefined in this case. |
| * |
| * CHECKSUM_UNNECESSARY: |
| * |
| * The hardware you're dealing with doesn't calculate the full checksum |
| * (as in CHECKSUM_COMPLETE), but it does parse headers and verify checksums |
| * for specific protocols. For such packets it will set CHECKSUM_UNNECESSARY |
| * if their checksums are okay. skb->csum is still undefined in this case |
| * though. A driver or device must never modify the checksum field in the |
| * packet even if checksum is verified. |
| * |
| * CHECKSUM_UNNECESSARY is applicable to following protocols: |
| * TCP: IPv6 and IPv4. |
| * UDP: IPv4 and IPv6. A device may apply CHECKSUM_UNNECESSARY to a |
| * zero UDP checksum for either IPv4 or IPv6, the networking stack |
| * may perform further validation in this case. |
| * GRE: only if the checksum is present in the header. |
| * SCTP: indicates the CRC in SCTP header has been validated. |
| * FCOE: indicates the CRC in FC frame has been validated. |
| * |
| * skb->csum_level indicates the number of consecutive checksums found in |
| * the packet minus one that have been verified as CHECKSUM_UNNECESSARY. |
| * For instance if a device receives an IPv6->UDP->GRE->IPv4->TCP packet |
| * and a device is able to verify the checksums for UDP (possibly zero), |
| * GRE (checksum flag is set), and TCP-- skb->csum_level would be set to |
| * two. If the device were only able to verify the UDP checksum and not |
| * GRE, either because it doesn't support GRE checksum of because GRE |
| * checksum is bad, skb->csum_level would be set to zero (TCP checksum is |
| * not considered in this case). |
| * |
| * CHECKSUM_COMPLETE: |
| * |
| * This is the most generic way. The device supplied checksum of the _whole_ |
| * packet as seen by netif_rx() and fills out in skb->csum. Meaning, the |
| * hardware doesn't need to parse L3/L4 headers to implement this. |
| * |
| * Notes: |
| * - Even if device supports only some protocols, but is able to produce |
| * skb->csum, it MUST use CHECKSUM_COMPLETE, not CHECKSUM_UNNECESSARY. |
| * - CHECKSUM_COMPLETE is not applicable to SCTP and FCoE protocols. |
| * |
| * CHECKSUM_PARTIAL: |
| * |
| * A checksum is set up to be offloaded to a device as described in the |
| * output description for CHECKSUM_PARTIAL. This may occur on a packet |
| * received directly from another Linux OS, e.g., a virtualized Linux kernel |
| * on the same host, or it may be set in the input path in GRO or remote |
| * checksum offload. For the purposes of checksum verification, the checksum |
| * referred to by skb->csum_start + skb->csum_offset and any preceding |
| * checksums in the packet are considered verified. Any checksums in the |
| * packet that are after the checksum being offloaded are not considered to |
| * be verified. |
| * |
| * C. Checksumming on transmit for non-GSO. The stack requests checksum offload |
| * in the skb->ip_summed for a packet. Values are: |
| * |
| * CHECKSUM_PARTIAL: |
| * |
| * The driver is required to checksum the packet as seen by hard_start_xmit() |
| * from skb->csum_start up to the end, and to record/write the checksum at |
| * offset skb->csum_start + skb->csum_offset. A driver may verify that the |
| * csum_start and csum_offset values are valid values given the length and |
| * offset of the packet, however they should not attempt to validate that the |
| * checksum refers to a legitimate transport layer checksum-- it is the |
| * purview of the stack to validate that csum_start and csum_offset are set |
| * correctly. |
| * |
| * When the stack requests checksum offload for a packet, the driver MUST |
| * ensure that the checksum is set correctly. A driver can either offload the |
| * checksum calculation to the device, or call skb_checksum_help (in the case |
| * that the device does not support offload for a particular checksum). |
| * |
| * NETIF_F_IP_CSUM and NETIF_F_IPV6_CSUM are being deprecated in favor of |
| * NETIF_F_HW_CSUM. New devices should use NETIF_F_HW_CSUM to indicate |
| * checksum offload capability. |
| * skb_csum_hwoffload_help() can be called to resolve CHECKSUM_PARTIAL based |
| * on network device checksumming capabilities: if a packet does not match |
| * them, skb_checksum_help or skb_crc32c_help (depending on the value of |
| * csum_not_inet, see item D.) is called to resolve the checksum. |
| * |
| * CHECKSUM_NONE: |
| * |
| * The skb was already checksummed by the protocol, or a checksum is not |
| * required. |
| * |
| * CHECKSUM_UNNECESSARY: |
| * |
| * This has the same meaning on as CHECKSUM_NONE for checksum offload on |
| * output. |
| * |
| * CHECKSUM_COMPLETE: |
| * Not used in checksum output. If a driver observes a packet with this value |
| * set in skbuff, if should treat as CHECKSUM_NONE being set. |
| * |
| * D. Non-IP checksum (CRC) offloads |
| * |
| * NETIF_F_SCTP_CRC - This feature indicates that a device is capable of |
| * offloading the SCTP CRC in a packet. To perform this offload the stack |
| * will set set csum_start and csum_offset accordingly, set ip_summed to |
| * CHECKSUM_PARTIAL and set csum_not_inet to 1, to provide an indication in |
| * the skbuff that the CHECKSUM_PARTIAL refers to CRC32c. |
| * A driver that supports both IP checksum offload and SCTP CRC32c offload |
| * must verify which offload is configured for a packet by testing the |
| * value of skb->csum_not_inet; skb_crc32c_csum_help is provided to resolve |
| * CHECKSUM_PARTIAL on skbs where csum_not_inet is set to 1. |
| * |
| * NETIF_F_FCOE_CRC - This feature indicates that a device is capable of |
| * offloading the FCOE CRC in a packet. To perform this offload the stack |
| * will set ip_summed to CHECKSUM_PARTIAL and set csum_start and csum_offset |
| * accordingly. Note the there is no indication in the skbuff that the |
| * CHECKSUM_PARTIAL refers to an FCOE checksum, a driver that supports |
| * both IP checksum offload and FCOE CRC offload must verify which offload |
| * is configured for a packet presumably by inspecting packet headers. |
| * |
| * E. Checksumming on output with GSO. |
| * |
| * In the case of a GSO packet (skb_is_gso(skb) is true), checksum offload |
| * is implied by the SKB_GSO_* flags in gso_type. Most obviously, if the |
| * gso_type is SKB_GSO_TCPV4 or SKB_GSO_TCPV6, TCP checksum offload as |
| * part of the GSO operation is implied. If a checksum is being offloaded |
| * with GSO then ip_summed is CHECKSUM_PARTIAL, csum_start and csum_offset |
| * are set to refer to the outermost checksum being offload (two offloaded |
| * checksums are possible with UDP encapsulation). |
| */ |
| |
| /* Don't change this without changing skb_csum_unnecessary! */ |
| #define CHECKSUM_NONE 0 |
| #define CHECKSUM_UNNECESSARY 1 |
| #define CHECKSUM_COMPLETE 2 |
| #define CHECKSUM_PARTIAL 3 |
| |
| /* Maximum value in skb->csum_level */ |
| #define SKB_MAX_CSUM_LEVEL 3 |
| |
| #define SKB_DATA_ALIGN(X) ALIGN(X, SMP_CACHE_BYTES) |
| #define SKB_WITH_OVERHEAD(X) \ |
| ((X) - SKB_DATA_ALIGN(sizeof(struct skb_shared_info))) |
| #define SKB_MAX_ORDER(X, ORDER) \ |
| SKB_WITH_OVERHEAD((PAGE_SIZE << (ORDER)) - (X)) |
| #define SKB_MAX_HEAD(X) (SKB_MAX_ORDER((X), 0)) |
| #define SKB_MAX_ALLOC (SKB_MAX_ORDER(0, 2)) |
| |
| /* return minimum truesize of one skb containing X bytes of data */ |
| #define SKB_TRUESIZE(X) ((X) + \ |
| SKB_DATA_ALIGN(sizeof(struct sk_buff)) + \ |
| SKB_DATA_ALIGN(sizeof(struct skb_shared_info))) |
| |
| struct net_device; |
| struct scatterlist; |
| struct pipe_inode_info; |
| struct iov_iter; |
| struct napi_struct; |
| |
| #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) |
| struct nf_conntrack { |
| atomic_t use; |
| }; |
| #endif |
| |
| #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) |
| struct nf_bridge_info { |
| refcount_t use; |
| enum { |
| BRNF_PROTO_UNCHANGED, |
| BRNF_PROTO_8021Q, |
| BRNF_PROTO_PPPOE |
| } orig_proto:8; |
| u8 pkt_otherhost:1; |
| u8 in_prerouting:1; |
| u8 bridged_dnat:1; |
| __u16 frag_max_size; |
| struct net_device *physindev; |
| |
| /* always valid & non-NULL from FORWARD on, for physdev match */ |
| struct net_device *physoutdev; |
| union { |
| /* prerouting: detect dnat in orig/reply direction */ |
| __be32 ipv4_daddr; |
| struct in6_addr ipv6_daddr; |
| |
| /* after prerouting + nat detected: store original source |
| * mac since neigh resolution overwrites it, only used while |
| * skb is out in neigh layer. |
| */ |
| char neigh_header[8]; |
| }; |
| }; |
| #endif |
| |
| struct sk_buff_head { |
| /* These two members must be first. */ |
| struct sk_buff *next; |
| struct sk_buff *prev; |
| |
| __u32 qlen; |
| spinlock_t lock; |
| }; |
| |
| struct sk_buff; |
| |
| /* To allow 64K frame to be packed as single skb without frag_list we |
| * require 64K/PAGE_SIZE pages plus 1 additional page to allow for |
| * buffers which do not start on a page boundary. |
| * |
| * Since GRO uses frags we allocate at least 16 regardless of page |
| * size. |
| */ |
| #if (65536/PAGE_SIZE + 1) < 16 |
| #define MAX_SKB_FRAGS 16UL |
| #else |
| #define MAX_SKB_FRAGS (65536/PAGE_SIZE + 1) |
| #endif |
| extern int sysctl_max_skb_frags; |
| |
| /* Set skb_shinfo(skb)->gso_size to this in case you want skb_segment to |
| * segment using its current segmentation instead. |
| */ |
| #define GSO_BY_FRAGS 0xFFFF |
| |
| typedef struct skb_frag_struct skb_frag_t; |
| |
| struct skb_frag_struct { |
| struct { |
| struct page *p; |
| } page; |
| #if (BITS_PER_LONG > 32) || (PAGE_SIZE >= 65536) |
| __u32 page_offset; |
| __u32 size; |
| #else |
| __u16 page_offset; |
| __u16 size; |
| #endif |
| }; |
| |
| static inline unsigned int skb_frag_size(const skb_frag_t *frag) |
| { |
| return frag->size; |
| } |
| |
| static inline void skb_frag_size_set(skb_frag_t *frag, unsigned int size) |
| { |
| frag->size = size; |
| } |
| |
| static inline void skb_frag_size_add(skb_frag_t *frag, int delta) |
| { |
| frag->size += delta; |
| } |
| |
| static inline void skb_frag_size_sub(skb_frag_t *frag, int delta) |
| { |
| frag->size -= delta; |
| } |
| |
| static inline bool skb_frag_must_loop(struct page *p) |
| { |
| #if defined(CONFIG_HIGHMEM) |
| if (PageHighMem(p)) |
| return true; |
| #endif |
| return false; |
| } |
| |
| /** |
| * skb_frag_foreach_page - loop over pages in a fragment |
| * |
| * @f: skb frag to operate on |
| * @f_off: offset from start of f->page.p |
| * @f_len: length from f_off to loop over |
| * @p: (temp var) current page |
| * @p_off: (temp var) offset from start of current page, |
| * non-zero only on first page. |
| * @p_len: (temp var) length in current page, |
| * < PAGE_SIZE only on first and last page. |
| * @copied: (temp var) length so far, excluding current p_len. |
| * |
| * A fragment can hold a compound page, in which case per-page |
| * operations, notably kmap_atomic, must be called for each |
| * regular page. |
| */ |
| #define skb_frag_foreach_page(f, f_off, f_len, p, p_off, p_len, copied) \ |
| for (p = skb_frag_page(f) + ((f_off) >> PAGE_SHIFT), \ |
| p_off = (f_off) & (PAGE_SIZE - 1), \ |
| p_len = skb_frag_must_loop(p) ? \ |
| min_t(u32, f_len, PAGE_SIZE - p_off) : f_len, \ |
| copied = 0; \ |
| copied < f_len; \ |
| copied += p_len, p++, p_off = 0, \ |
| p_len = min_t(u32, f_len - copied, PAGE_SIZE)) \ |
| |
| #define HAVE_HW_TIME_STAMP |
| |
| /** |
| * struct skb_shared_hwtstamps - hardware time stamps |
| * @hwtstamp: hardware time stamp transformed into duration |
| * since arbitrary point in time |
| * |
| * Software time stamps generated by ktime_get_real() are stored in |
| * skb->tstamp. |
| * |
| * hwtstamps can only be compared against other hwtstamps from |
| * the same device. |
| * |
| * This structure is attached to packets as part of the |
| * &skb_shared_info. Use skb_hwtstamps() to get a pointer. |
| */ |
| struct skb_shared_hwtstamps { |
| ktime_t hwtstamp; |
| }; |
| |
| /* Definitions for tx_flags in struct skb_shared_info */ |
| enum { |
| /* generate hardware time stamp */ |
| SKBTX_HW_TSTAMP = 1 << 0, |
| |
| /* generate software time stamp when queueing packet to NIC */ |
| SKBTX_SW_TSTAMP = 1 << 1, |
| |
| /* device driver is going to provide hardware time stamp */ |
| SKBTX_IN_PROGRESS = 1 << 2, |
| |
| /* device driver supports TX zero-copy buffers */ |
| SKBTX_DEV_ZEROCOPY = 1 << 3, |
| |
| /* generate wifi status information (where possible) */ |
| SKBTX_WIFI_STATUS = 1 << 4, |
| |
| /* This indicates at least one fragment might be overwritten |
| * (as in vmsplice(), sendfile() ...) |
| * If we need to compute a TX checksum, we'll need to copy |
| * all frags to avoid possible bad checksum |
| */ |
| SKBTX_SHARED_FRAG = 1 << 5, |
| |
| /* generate software time stamp when entering packet scheduling */ |
| SKBTX_SCHED_TSTAMP = 1 << 6, |
| }; |
| |
| #define SKBTX_ZEROCOPY_FRAG (SKBTX_DEV_ZEROCOPY | SKBTX_SHARED_FRAG) |
| #define SKBTX_ANY_SW_TSTAMP (SKBTX_SW_TSTAMP | \ |
| SKBTX_SCHED_TSTAMP) |
| #define SKBTX_ANY_TSTAMP (SKBTX_HW_TSTAMP | SKBTX_ANY_SW_TSTAMP) |
| |
| /* |
| * The callback notifies userspace to release buffers when skb DMA is done in |
| * lower device, the skb last reference should be 0 when calling this. |
| * The zerocopy_success argument is true if zero copy transmit occurred, |
| * false on data copy or out of memory error caused by data copy attempt. |
| * The ctx field is used to track device context. |
| * The desc field is used to track userspace buffer index. |
| */ |
| struct ubuf_info { |
| void (*callback)(struct ubuf_info *, bool zerocopy_success); |
| union { |
| struct { |
| unsigned long desc; |
| void *ctx; |
| }; |
| struct { |
| u32 id; |
| u16 len; |
| u16 zerocopy:1; |
| u32 bytelen; |
| }; |
| }; |
| refcount_t refcnt; |
| |
| struct mmpin { |
| struct user_struct *user; |
| unsigned int num_pg; |
| } mmp; |
| }; |
| |
| #define skb_uarg(SKB) ((struct ubuf_info *)(skb_shinfo(SKB)->destructor_arg)) |
| |
| struct ubuf_info *sock_zerocopy_alloc(struct sock *sk, size_t size); |
| struct ubuf_info *sock_zerocopy_realloc(struct sock *sk, size_t size, |
| struct ubuf_info *uarg); |
| |
| static inline void sock_zerocopy_get(struct ubuf_info *uarg) |
| { |
| refcount_inc(&uarg->refcnt); |
| } |
| |
| void sock_zerocopy_put(struct ubuf_info *uarg); |
| void sock_zerocopy_put_abort(struct ubuf_info *uarg); |
| |
| void sock_zerocopy_callback(struct ubuf_info *uarg, bool success); |
| |
| int skb_zerocopy_iter_stream(struct sock *sk, struct sk_buff *skb, |
| struct msghdr *msg, int len, |
| struct ubuf_info *uarg); |
| |
| /* This data is invariant across clones and lives at |
| * the end of the header data, ie. at skb->end. |
| */ |
| struct skb_shared_info { |
| unsigned short _unused; |
| unsigned char nr_frags; |
| __u8 tx_flags; |
| unsigned short gso_size; |
| /* Warning: this field is not always filled in (UFO)! */ |
| unsigned short gso_segs; |
| struct sk_buff *frag_list; |
| struct skb_shared_hwtstamps hwtstamps; |
| unsigned int gso_type; |
| u32 tskey; |
| __be32 ip6_frag_id; |
| |
| /* |
| * Warning : all fields before dataref are cleared in __alloc_skb() |
| */ |
| atomic_t dataref; |
| |
| /* Intermediate layers must ensure that destructor_arg |
| * remains valid until skb destructor */ |
| void * destructor_arg; |
| |
| /* must be last field, see pskb_expand_head() */ |
| skb_frag_t frags[MAX_SKB_FRAGS]; |
| }; |
| |
| /* We divide dataref into two halves. The higher 16 bits hold references |
| * to the payload part of skb->data. The lower 16 bits hold references to |
| * the entire skb->data. A clone of a headerless skb holds the length of |
| * the header in skb->hdr_len. |
| * |
| * All users must obey the rule that the skb->data reference count must be |
| * greater than or equal to the payload reference count. |
| * |
| * Holding a reference to the payload part means that the user does not |
| * care about modifications to the header part of skb->data. |
| */ |
| #define SKB_DATAREF_SHIFT 16 |
| #define SKB_DATAREF_MASK ((1 << SKB_DATAREF_SHIFT) - 1) |
| |
| |
| enum { |
| SKB_FCLONE_UNAVAILABLE, /* skb has no fclone (from head_cache) */ |
| SKB_FCLONE_ORIG, /* orig skb (from fclone_cache) */ |
| SKB_FCLONE_CLONE, /* companion fclone skb (from fclone_cache) */ |
| }; |
| |
| enum { |
| SKB_GSO_TCPV4 = 1 << 0, |
| |
| /* This indicates the skb is from an untrusted source. */ |
| SKB_GSO_DODGY = 1 << 1, |
| |
| /* This indicates the tcp segment has CWR set. */ |
| SKB_GSO_TCP_ECN = 1 << 2, |
| |
| SKB_GSO_TCP_FIXEDID = 1 << 3, |
| |
| SKB_GSO_TCPV6 = 1 << 4, |
| |
| SKB_GSO_FCOE = 1 << 5, |
| |
| SKB_GSO_GRE = 1 << 6, |
| |
| SKB_GSO_GRE_CSUM = 1 << 7, |
| |
| SKB_GSO_IPXIP4 = 1 << 8, |
| |
| SKB_GSO_IPXIP6 = 1 << 9, |
| |
| SKB_GSO_UDP_TUNNEL = 1 << 10, |
| |
| SKB_GSO_UDP_TUNNEL_CSUM = 1 << 11, |
| |
| SKB_GSO_PARTIAL = 1 << 12, |
| |
| SKB_GSO_TUNNEL_REMCSUM = 1 << 13, |
| |
| SKB_GSO_SCTP = 1 << 14, |
| |
| SKB_GSO_ESP = 1 << 15, |
| }; |
| |
| #if BITS_PER_LONG > 32 |
| #define NET_SKBUFF_DATA_USES_OFFSET 1 |
| #endif |
| |
| #ifdef NET_SKBUFF_DATA_USES_OFFSET |
| typedef unsigned int sk_buff_data_t; |
| #else |
| typedef unsigned char *sk_buff_data_t; |
| #endif |
| |
| /** |
| * struct sk_buff - socket buffer |
| * @next: Next buffer in list |
| * @prev: Previous buffer in list |
| * @tstamp: Time we arrived/left |
| * @rbnode: RB tree node, alternative to next/prev for netem/tcp |
| * @sk: Socket we are owned by |
| * @dev: Device we arrived on/are leaving by |
| * @cb: Control buffer. Free for use by every layer. Put private vars here |
| * @_skb_refdst: destination entry (with norefcount bit) |
| * @sp: the security path, used for xfrm |
| * @len: Length of actual data |
| * @data_len: Data length |
| * @mac_len: Length of link layer header |
| * @hdr_len: writable header length of cloned skb |
| * @csum: Checksum (must include start/offset pair) |
| * @csum_start: Offset from skb->head where checksumming should start |
| * @csum_offset: Offset from csum_start where checksum should be stored |
| * @priority: Packet queueing priority |
| * @ignore_df: allow local fragmentation |
| * @cloned: Head may be cloned (check refcnt to be sure) |
| * @ip_summed: Driver fed us an IP checksum |
| * @nohdr: Payload reference only, must not modify header |
| * @pkt_type: Packet class |
| * @fclone: skbuff clone status |
| * @ipvs_property: skbuff is owned by ipvs |
| * @tc_skip_classify: do not classify packet. set by IFB device |
| * @tc_at_ingress: used within tc_classify to distinguish in/egress |
| * @tc_redirected: packet was redirected by a tc action |
| * @tc_from_ingress: if tc_redirected, tc_at_ingress at time of redirect |
| * @peeked: this packet has been seen already, so stats have been |
| * done for it, don't do them again |
| * @nf_trace: netfilter packet trace flag |
| * @protocol: Packet protocol from driver |
| * @destructor: Destruct function |
| * @_nfct: Associated connection, if any (with nfctinfo bits) |
| * @nf_bridge: Saved data about a bridged frame - see br_netfilter.c |
| * @skb_iif: ifindex of device we arrived on |
| * @tc_index: Traffic control index |
| * @hash: the packet hash |
| * @queue_mapping: Queue mapping for multiqueue devices |
| * @xmit_more: More SKBs are pending for this queue |
| * @ndisc_nodetype: router type (from link layer) |
| * @ooo_okay: allow the mapping of a socket to a queue to be changed |
| * @l4_hash: indicate hash is a canonical 4-tuple hash over transport |
| * ports. |
| * @sw_hash: indicates hash was computed in software stack |
| * @wifi_acked_valid: wifi_acked was set |
| * @wifi_acked: whether frame was acked on wifi or not |
| * @no_fcs: Request NIC to treat last 4 bytes as Ethernet FCS |
| * @csum_not_inet: use CRC32c to resolve CHECKSUM_PARTIAL |
| * @dst_pending_confirm: need to confirm neighbour |
| * @napi_id: id of the NAPI struct this skb came from |
| * @secmark: security marking |
| * @mark: Generic packet mark |
| * @vlan_proto: vlan encapsulation protocol |
| * @vlan_tci: vlan tag control information |
| * @inner_protocol: Protocol (encapsulation) |
| * @inner_transport_header: Inner transport layer header (encapsulation) |
| * @inner_network_header: Network layer header (encapsulation) |
| * @inner_mac_header: Link layer header (encapsulation) |
| * @transport_header: Transport layer header |
| * @network_header: Network layer header |
| * @mac_header: Link layer header |
| * @tail: Tail pointer |
| * @end: End pointer |
| * @head: Head of buffer |
| * @data: Data head pointer |
| * @truesize: Buffer size |
| * @users: User count - see {datagram,tcp}.c |
| */ |
| |
| struct sk_buff { |
| union { |
| struct { |
| /* These two members must be first. */ |
| struct sk_buff *next; |
| struct sk_buff *prev; |
| |
| union { |
| ktime_t tstamp; |
| u64 skb_mstamp; |
| }; |
| }; |
| struct rb_node rbnode; /* used in netem & tcp stack */ |
| }; |
| struct sock *sk; |
| |
| union { |
| struct net_device *dev; |
| /* Some protocols might use this space to store information, |
| * while device pointer would be NULL. |
| * UDP receive path is one user. |
| */ |
| unsigned long dev_scratch; |
| }; |
| /* |
| * This is the control buffer. It is free to use for every |
| * layer. Please put your private variables there. If you |
| * want to keep them across layers you have to do a skb_clone() |
| * first. This is owned by whoever has the skb queued ATM. |
| */ |
| char cb[48] __aligned(8); |
| |
| unsigned long _skb_refdst; |
| void (*destructor)(struct sk_buff *skb); |
| #ifdef CONFIG_XFRM |
| struct sec_path *sp; |
| #endif |
| #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) |
| unsigned long _nfct; |
| #endif |
| #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) |
| struct nf_bridge_info *nf_bridge; |
| #endif |
| unsigned int len, |
| data_len; |
| __u16 mac_len, |
| hdr_len; |
| |
| /* Following fields are _not_ copied in __copy_skb_header() |
| * Note that queue_mapping is here mostly to fill a hole. |
| */ |
| kmemcheck_bitfield_begin(flags1); |
| __u16 queue_mapping; |
| |
| /* if you move cloned around you also must adapt those constants */ |
| #ifdef __BIG_ENDIAN_BITFIELD |
| #define CLONED_MASK (1 << 7) |
| #else |
| #define CLONED_MASK 1 |
| #endif |
| #define CLONED_OFFSET() offsetof(struct sk_buff, __cloned_offset) |
| |
| __u8 __cloned_offset[0]; |
| __u8 cloned:1, |
| nohdr:1, |
| fclone:2, |
| peeked:1, |
| head_frag:1, |
| xmit_more:1, |
| __unused:1; /* one bit hole */ |
| kmemcheck_bitfield_end(flags1); |
| |
| /* fields enclosed in headers_start/headers_end are copied |
| * using a single memcpy() in __copy_skb_header() |
| */ |
| /* private: */ |
| __u32 headers_start[0]; |
| /* public: */ |
| |
| /* if you move pkt_type around you also must adapt those constants */ |
| #ifdef __BIG_ENDIAN_BITFIELD |
| #define PKT_TYPE_MAX (7 << 5) |
| #else |
| #define PKT_TYPE_MAX 7 |
| #endif |
| #define PKT_TYPE_OFFSET() offsetof(struct sk_buff, __pkt_type_offset) |
| |
| __u8 __pkt_type_offset[0]; |
| __u8 pkt_type:3; |
| __u8 pfmemalloc:1; |
| __u8 ignore_df:1; |
| |
| __u8 nf_trace:1; |
| __u8 ip_summed:2; |
| __u8 ooo_okay:1; |
| __u8 l4_hash:1; |
| __u8 sw_hash:1; |
| __u8 wifi_acked_valid:1; |
| __u8 wifi_acked:1; |
| |
| __u8 no_fcs:1; |
| /* Indicates the inner headers are valid in the skbuff. */ |
| __u8 encapsulation:1; |
| __u8 encap_hdr_csum:1; |
| __u8 csum_valid:1; |
| __u8 csum_complete_sw:1; |
| __u8 csum_level:2; |
| __u8 csum_not_inet:1; |
| |
| __u8 dst_pending_confirm:1; |
| #ifdef CONFIG_IPV6_NDISC_NODETYPE |
| __u8 ndisc_nodetype:2; |
| #endif |
| __u8 ipvs_property:1; |
| __u8 inner_protocol_type:1; |
| __u8 remcsum_offload:1; |
| #ifdef CONFIG_NET_SWITCHDEV |
| __u8 offload_fwd_mark:1; |
| #endif |
| #ifdef CONFIG_NET_CLS_ACT |
| __u8 tc_skip_classify:1; |
| __u8 tc_at_ingress:1; |
| __u8 tc_redirected:1; |
| __u8 tc_from_ingress:1; |
| #endif |
| |
| #ifdef CONFIG_NET_SCHED |
| __u16 tc_index; /* traffic control index */ |
| #endif |
| |
| union { |
| __wsum csum; |
| struct { |
| __u16 csum_start; |
| __u16 csum_offset; |
| }; |
| }; |
| __u32 priority; |
| int skb_iif; |
| __u32 hash; |
| __be16 vlan_proto; |
| __u16 vlan_tci; |
| #if defined(CONFIG_NET_RX_BUSY_POLL) || defined(CONFIG_XPS) |
| union { |
| unsigned int napi_id; |
| unsigned int sender_cpu; |
| }; |
| #endif |
| #ifdef CONFIG_NETWORK_SECMARK |
| __u32 secmark; |
| #endif |
| |
| union { |
| __u32 mark; |
| __u32 reserved_tailroom; |
| }; |
| |
| union { |
| __be16 inner_protocol; |
| __u8 inner_ipproto; |
| }; |
| |
| __u16 inner_transport_header; |
| __u16 inner_network_header; |
| __u16 inner_mac_header; |
| |
| __be16 protocol; |
| __u16 transport_header; |
| __u16 network_header; |
| __u16 mac_header; |
| |
| /* private: */ |
| __u32 headers_end[0]; |
| /* public: */ |
| |
| /* These elements must be at the end, see alloc_skb() for details. */ |
| sk_buff_data_t tail; |
| sk_buff_data_t end; |
| unsigned char *head, |
| *data; |
| unsigned int truesize; |
| refcount_t users; |
| }; |
| |
| #ifdef __KERNEL__ |
| /* |
| * Handling routines are only of interest to the kernel |
| */ |
| #include <linux/slab.h> |
| |
| |
| #define SKB_ALLOC_FCLONE 0x01 |
| #define SKB_ALLOC_RX 0x02 |
| #define SKB_ALLOC_NAPI 0x04 |
| |
| /* Returns true if the skb was allocated from PFMEMALLOC reserves */ |
| static inline bool skb_pfmemalloc(const struct sk_buff *skb) |
| { |
| return unlikely(skb->pfmemalloc); |
| } |
| |
| /* |
| * skb might have a dst pointer attached, refcounted or not. |
| * _skb_refdst low order bit is set if refcount was _not_ taken |
| */ |
| #define SKB_DST_NOREF 1UL |
| #define SKB_DST_PTRMASK ~(SKB_DST_NOREF) |
| |
| #define SKB_NFCT_PTRMASK ~(7UL) |
| /** |
| * skb_dst - returns skb dst_entry |
| * @skb: buffer |
| * |
| * Returns skb dst_entry, regardless of reference taken or not. |
| */ |
| static inline struct dst_entry *skb_dst(const struct sk_buff *skb) |
| { |
| /* If refdst was not refcounted, check we still are in a |
| * rcu_read_lock section |
| */ |
| WARN_ON((skb->_skb_refdst & SKB_DST_NOREF) && |
| !rcu_read_lock_held() && |
| !rcu_read_lock_bh_held()); |
| return (struct dst_entry *)(skb->_skb_refdst & SKB_DST_PTRMASK); |
| } |
| |
| /** |
| * skb_dst_set - sets skb dst |
| * @skb: buffer |
| * @dst: dst entry |
| * |
| * Sets skb dst, assuming a reference was taken on dst and should |
| * be released by skb_dst_drop() |
| */ |
| static inline void skb_dst_set(struct sk_buff *skb, struct dst_entry *dst) |
| { |
| skb->_skb_refdst = (unsigned long)dst; |
| } |
| |
| /** |
| * skb_dst_set_noref - sets skb dst, hopefully, without taking reference |
| * @skb: buffer |
| * @dst: dst entry |
| * |
| * Sets skb dst, assuming a reference was not taken on dst. |
| * If dst entry is cached, we do not take reference and dst_release |
| * will be avoided by refdst_drop. If dst entry is not cached, we take |
| * reference, so that last dst_release can destroy the dst immediately. |
| */ |
| static inline void skb_dst_set_noref(struct sk_buff *skb, struct dst_entry *dst) |
| { |
| WARN_ON(!rcu_read_lock_held() && !rcu_read_lock_bh_held()); |
| skb->_skb_refdst = (unsigned long)dst | SKB_DST_NOREF; |
| } |
| |
| /** |
| * skb_dst_is_noref - Test if skb dst isn't refcounted |
| * @skb: buffer |
| */ |
| static inline bool skb_dst_is_noref(const struct sk_buff *skb) |
| { |
| return (skb->_skb_refdst & SKB_DST_NOREF) && skb_dst(skb); |
| } |
| |
| static inline struct rtable *skb_rtable(const struct sk_buff *skb) |
| { |
| return (struct rtable *)skb_dst(skb); |
| } |
| |
| /* For mangling skb->pkt_type from user space side from applications |
| * such as nft, tc, etc, we only allow a conservative subset of |
| * possible pkt_types to be set. |
| */ |
| static inline bool skb_pkt_type_ok(u32 ptype) |
| { |
| return ptype <= PACKET_OTHERHOST; |
| } |
| |
| static inline unsigned int skb_napi_id(const struct sk_buff *skb) |
| { |
| #ifdef CONFIG_NET_RX_BUSY_POLL |
| return skb->napi_id; |
| #else |
| return 0; |
| #endif |
| } |
| |
| /* decrement the reference count and return true if we can free the skb */ |
| static inline bool skb_unref(struct sk_buff *skb) |
| { |
| if (unlikely(!skb)) |
| return false; |
| if (likely(refcount_read(&skb->users) == 1)) |
| smp_rmb(); |
| else if (likely(!refcount_dec_and_test(&skb->users))) |
| return false; |
| |
| return true; |
| } |
| |
| void skb_release_head_state(struct sk_buff *skb); |
| void kfree_skb(struct sk_buff *skb); |
| void kfree_skb_list(struct sk_buff *segs); |
| void skb_tx_error(struct sk_buff *skb); |
| void consume_skb(struct sk_buff *skb); |
| void __consume_stateless_skb(struct sk_buff *skb); |
| void __kfree_skb(struct sk_buff *skb); |
| extern struct kmem_cache *skbuff_head_cache; |
| |
| void kfree_skb_partial(struct sk_buff *skb, bool head_stolen); |
| bool skb_try_coalesce(struct sk_buff *to, struct sk_buff *from, |
| bool *fragstolen, int *delta_truesize); |
| |
| struct sk_buff *__alloc_skb(unsigned int size, gfp_t priority, int flags, |
| int node); |
| struct sk_buff *__build_skb(void *data, unsigned int frag_size); |
| struct sk_buff *build_skb(void *data, unsigned int frag_size); |
| static inline struct sk_buff *alloc_skb(unsigned int size, |
| gfp_t priority) |
| { |
| return __alloc_skb(size, priority, 0, NUMA_NO_NODE); |
| } |
| |
| struct sk_buff *alloc_skb_with_frags(unsigned long header_len, |
| unsigned long data_len, |
| int max_page_order, |
| int *errcode, |
| gfp_t gfp_mask); |
| |
| /* Layout of fast clones : [skb1][skb2][fclone_ref] */ |
| struct sk_buff_fclones { |
| struct sk_buff skb1; |
| |
| struct sk_buff skb2; |
| |
| refcount_t fclone_ref; |
| }; |
| |
| /** |
| * skb_fclone_busy - check if fclone is busy |
| * @sk: socket |
| * @skb: buffer |
| * |
| * Returns true if skb is a fast clone, and its clone is not freed. |
| * Some drivers call skb_orphan() in their ndo_start_xmit(), |
| * so we also check that this didnt happen. |
| */ |
| static inline bool skb_fclone_busy(const struct sock *sk, |
| const struct sk_buff *skb) |
| { |
| const struct sk_buff_fclones *fclones; |
| |
| fclones = container_of(skb, struct sk_buff_fclones, skb1); |
| |
| return skb->fclone == SKB_FCLONE_ORIG && |
| refcount_read(&fclones->fclone_ref) > 1 && |
| fclones->skb2.sk == sk; |
| } |
| |
| static inline struct sk_buff *alloc_skb_fclone(unsigned int size, |
| gfp_t priority) |
| { |
| return __alloc_skb(size, priority, SKB_ALLOC_FCLONE, NUMA_NO_NODE); |
| } |
| |
| struct sk_buff *skb_morph(struct sk_buff *dst, struct sk_buff *src); |
| int skb_copy_ubufs(struct sk_buff *skb, gfp_t gfp_mask); |
| struct sk_buff *skb_clone(struct sk_buff *skb, gfp_t priority); |
| struct sk_buff *skb_copy(const struct sk_buff *skb, gfp_t priority); |
| struct sk_buff *__pskb_copy_fclone(struct sk_buff *skb, int headroom, |
| gfp_t gfp_mask, bool fclone); |
| static inline struct sk_buff *__pskb_copy(struct sk_buff *skb, int headroom, |
| gfp_t gfp_mask) |
| { |
| return __pskb_copy_fclone(skb, headroom, gfp_mask, false); |
| } |
| |
| int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail, gfp_t gfp_mask); |
| struct sk_buff *skb_realloc_headroom(struct sk_buff *skb, |
| unsigned int headroom); |
| struct sk_buff *skb_copy_expand(const struct sk_buff *skb, int newheadroom, |
| int newtailroom, gfp_t priority); |
| int __must_check skb_to_sgvec_nomark(struct sk_buff *skb, struct scatterlist *sg, |
| int offset, int len); |
| int __must_check skb_to_sgvec(struct sk_buff *skb, struct scatterlist *sg, |
| int offset, int len); |
| int skb_cow_data(struct sk_buff *skb, int tailbits, struct sk_buff **trailer); |
| int __skb_pad(struct sk_buff *skb, int pad, bool free_on_error); |
| |
| /** |
| * skb_pad - zero pad the tail of an skb |
| * @skb: buffer to pad |
| * @pad: space to pad |
| * |
| * Ensure that a buffer is followed by a padding area that is zero |
| * filled. Used by network drivers which may DMA or transfer data |
| * beyond the buffer end onto the wire. |
| * |
| * May return error in out of memory cases. The skb is freed on error. |
| */ |
| static inline int skb_pad(struct sk_buff *skb, int pad) |
| { |
| return __skb_pad(skb, pad, true); |
| } |
| #define dev_kfree_skb(a) consume_skb(a) |
| |
| int skb_append_datato_frags(struct sock *sk, struct sk_buff *skb, |
| int getfrag(void *from, char *to, int offset, |
| int len, int odd, struct sk_buff *skb), |
| void *from, int length); |
| |
| int skb_append_pagefrags(struct sk_buff *skb, struct page *page, |
| int offset, size_t size); |
| |
| struct skb_seq_state { |
| __u32 lower_offset; |
| __u32 upper_offset; |
| __u32 frag_idx; |
| __u32 stepped_offset; |
| struct sk_buff *root_skb; |
| struct sk_buff *cur_skb; |
| __u8 *frag_data; |
| }; |
| |
| void skb_prepare_seq_read(struct sk_buff *skb, unsigned int from, |
| unsigned int to, struct skb_seq_state *st); |
| unsigned int skb_seq_read(unsigned int consumed, const u8 **data, |
| struct skb_seq_state *st); |
| void skb_abort_seq_read(struct skb_seq_state *st); |
| |
| unsigned int skb_find_text(struct sk_buff *skb, unsigned int from, |
| unsigned int to, struct ts_config *config); |
| |
| /* |
| * Packet hash types specify the type of hash in skb_set_hash. |
| * |
| * Hash types refer to the protocol layer addresses which are used to |
| * construct a packet's hash. The hashes are used to differentiate or identify |
| * flows of the protocol layer for the hash type. Hash types are either |
| * layer-2 (L2), layer-3 (L3), or layer-4 (L4). |
| * |
| * Properties of hashes: |
| * |
| * 1) Two packets in different flows have different hash values |
| * 2) Two packets in the same flow should have the same hash value |
| * |
| * A hash at a higher layer is considered to be more specific. A driver should |
| * set the most specific hash possible. |
| * |
| * A driver cannot indicate a more specific hash than the layer at which a hash |
| * was computed. For instance an L3 hash cannot be set as an L4 hash. |
| * |
| * A driver may indicate a hash level which is less specific than the |
| * actual layer the hash was computed on. For instance, a hash computed |
| * at L4 may be considered an L3 hash. This should only be done if the |
| * driver can't unambiguously determine that the HW computed the hash at |
| * the higher layer. Note that the "should" in the second property above |
| * permits this. |
| */ |
| enum pkt_hash_types { |
| PKT_HASH_TYPE_NONE, /* Undefined type */ |
| PKT_HASH_TYPE_L2, /* Input: src_MAC, dest_MAC */ |
| PKT_HASH_TYPE_L3, /* Input: src_IP, dst_IP */ |
| PKT_HASH_TYPE_L4, /* Input: src_IP, dst_IP, src_port, dst_port */ |
| }; |
| |
| static inline void skb_clear_hash(struct sk_buff *skb) |
| { |
| skb->hash = 0; |
| skb->sw_hash = 0; |
| skb->l4_hash = 0; |
| } |
| |
| static inline void skb_clear_hash_if_not_l4(struct sk_buff *skb) |
| { |
| if (!skb->l4_hash) |
| skb_clear_hash(skb); |
| } |
| |
| static inline void |
| __skb_set_hash(struct sk_buff *skb, __u32 hash, bool is_sw, bool is_l4) |
| { |
| skb->l4_hash = is_l4; |
| skb->sw_hash = is_sw; |
| skb->hash = hash; |
| } |
| |
| static inline void |
| skb_set_hash(struct sk_buff *skb, __u32 hash, enum pkt_hash_types type) |
| { |
| /* Used by drivers to set hash from HW */ |
| __skb_set_hash(skb, hash, false, type == PKT_HASH_TYPE_L4); |
| } |
| |
| static inline void |
| __skb_set_sw_hash(struct sk_buff *skb, __u32 hash, bool is_l4) |
| { |
| __skb_set_hash(skb, hash, true, is_l4); |
| } |
| |
| void __skb_get_hash(struct sk_buff *skb); |
| u32 __skb_get_hash_symmetric(const struct sk_buff *skb); |
| u32 skb_get_poff(const struct sk_buff *skb); |
| u32 __skb_get_poff(const struct sk_buff *skb, void *data, |
| const struct flow_keys *keys, int hlen); |
| __be32 __skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto, |
| void *data, int hlen_proto); |
| |
| static inline __be32 skb_flow_get_ports(const struct sk_buff *skb, |
| int thoff, u8 ip_proto) |
| { |
| return __skb_flow_get_ports(skb, thoff, ip_proto, NULL, 0); |
| } |
| |
| void skb_flow_dissector_init(struct flow_dissector *flow_dissector, |
| const struct flow_dissector_key *key, |
| unsigned int key_count); |
| |
| bool __skb_flow_dissect(const struct sk_buff *skb, |
| struct flow_dissector *flow_dissector, |
| void *target_container, |
| void *data, __be16 proto, int nhoff, int hlen, |
| unsigned int flags); |
| |
| static inline bool skb_flow_dissect(const struct sk_buff *skb, |
| struct flow_dissector *flow_dissector, |
| void *target_container, unsigned int flags) |
| { |
| return __skb_flow_dissect(skb, flow_dissector, target_container, |
| NULL, 0, 0, 0, flags); |
| } |
| |
| static inline bool skb_flow_dissect_flow_keys(const struct sk_buff *skb, |
| struct flow_keys *flow, |
| unsigned int flags) |
| { |
| memset(flow, 0, sizeof(*flow)); |
| return __skb_flow_dissect(skb, &flow_keys_dissector, flow, |
| NULL, 0, 0, 0, flags); |
| } |
| |
| static inline bool skb_flow_dissect_flow_keys_buf(struct flow_keys *flow, |
| void *data, __be16 proto, |
| int nhoff, int hlen, |
| unsigned int flags) |
| { |
| memset(flow, 0, sizeof(*flow)); |
| return __skb_flow_dissect(NULL, &flow_keys_buf_dissector, flow, |
| data, proto, nhoff, hlen, flags); |
| } |
| |
| static inline __u32 skb_get_hash(struct sk_buff *skb) |
| { |
| if (!skb->l4_hash && !skb->sw_hash) |
| __skb_get_hash(skb); |
| |
| return skb->hash; |
| } |
| |
| static inline __u32 skb_get_hash_flowi6(struct sk_buff *skb, const struct flowi6 *fl6) |
| { |
| if (!skb->l4_hash && !skb->sw_hash) { |
| struct flow_keys keys; |
| __u32 hash = __get_hash_from_flowi6(fl6, &keys); |
| |
| __skb_set_sw_hash(skb, hash, flow_keys_have_l4(&keys)); |
| } |
| |
| return skb->hash; |
| } |
| |
| __u32 skb_get_hash_perturb(const struct sk_buff *skb, u32 perturb); |
| |
| static inline __u32 skb_get_hash_raw(const struct sk_buff *skb) |
| { |
| return skb->hash; |
| } |
| |
| static inline void skb_copy_hash(struct sk_buff *to, const struct sk_buff *from) |
| { |
| to->hash = from->hash; |
| to->sw_hash = from->sw_hash; |
| to->l4_hash = from->l4_hash; |
| }; |
| |
| #ifdef NET_SKBUFF_DATA_USES_OFFSET |
| static inline unsigned char *skb_end_pointer(const struct sk_buff *skb) |
| { |
| return skb->head + skb->end; |
| } |
| |
| static inline unsigned int skb_end_offset(const struct sk_buff *skb) |
| { |
| return skb->end; |
| } |
| #else |
| static inline unsigned char *skb_end_pointer(const struct sk_buff *skb) |
| { |
| return skb->end; |
| } |
| |
| static inline unsigned int skb_end_offset(const struct sk_buff *skb) |
| { |
| return skb->end - skb->head; |
| } |
| #endif |
| |
| /* Internal */ |
| #define skb_shinfo(SKB) ((struct skb_shared_info *)(skb_end_pointer(SKB))) |
| |
| static inline struct skb_shared_hwtstamps *skb_hwtstamps(struct sk_buff *skb) |
| { |
| return &skb_shinfo(skb)->hwtstamps; |
| } |
| |
| static inline struct ubuf_info *skb_zcopy(struct sk_buff *skb) |
| { |
| bool is_zcopy = skb && skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY; |
| |
| return is_zcopy ? skb_uarg(skb) : NULL; |
| } |
| |
| static inline void skb_zcopy_set(struct sk_buff *skb, struct ubuf_info *uarg) |
| { |
| if (skb && uarg && !skb_zcopy(skb)) { |
| sock_zerocopy_get(uarg); |
| skb_shinfo(skb)->destructor_arg = uarg; |
| skb_shinfo(skb)->tx_flags |= SKBTX_ZEROCOPY_FRAG; |
| } |
| } |
| |
| /* Release a reference on a zerocopy structure */ |
| static inline void skb_zcopy_clear(struct sk_buff *skb, bool zerocopy) |
| { |
| struct ubuf_info *uarg = skb_zcopy(skb); |
| |
| if (uarg) { |
| if (uarg->callback == sock_zerocopy_callback) { |
| uarg->zerocopy = uarg->zerocopy && zerocopy; |
| sock_zerocopy_put(uarg); |
| } else { |
| uarg->callback(uarg, zerocopy); |
| } |
| |
| skb_shinfo(skb)->tx_flags &= ~SKBTX_ZEROCOPY_FRAG; |
| } |
| } |
| |
| /* Abort a zerocopy operation and revert zckey on error in send syscall */ |
| static inline void skb_zcopy_abort(struct sk_buff *skb) |
| { |
| struct ubuf_info *uarg = skb_zcopy(skb); |
| |
| if (uarg) { |
| sock_zerocopy_put_abort(uarg); |
| skb_shinfo(skb)->tx_flags &= ~SKBTX_ZEROCOPY_FRAG; |
| } |
| } |
| |
| /** |
| * skb_queue_empty - check if a queue is empty |
| * @list: queue head |
| * |
| * Returns true if the queue is empty, false otherwise. |
| */ |
| static inline int skb_queue_empty(const struct sk_buff_head *list) |
| { |
| return list->next == (const struct sk_buff *) list; |
| } |
| |
| /** |
| * skb_queue_is_last - check if skb is the last entry in the queue |
| * @list: queue head |
| * @skb: buffer |
| * |
| * Returns true if @skb is the last buffer on the list. |
| */ |
| static inline bool skb_queue_is_last(const struct sk_buff_head *list, |
| const struct sk_buff *skb) |
| { |
| return skb->next == (const struct sk_buff *) list; |
| } |
| |
| /** |
| * skb_queue_is_first - check if skb is the first entry in the queue |
| * @list: queue head |
| * @skb: buffer |
| * |
| * Returns true if @skb is the first buffer on the list. |
| */ |
| static inline bool skb_queue_is_first(const struct sk_buff_head *list, |
| const struct sk_buff *skb) |
| { |
| return skb->prev == (const struct sk_buff *) list; |
| } |
| |
| /** |
| * skb_queue_next - return the next packet in the queue |
| * @list: queue head |
| * @skb: current buffer |
| * |
| * Return the next packet in @list after @skb. It is only valid to |
| * call this if skb_queue_is_last() evaluates to false. |
| */ |
| static inline struct sk_buff *skb_queue_next(const struct sk_buff_head *list, |
| const struct sk_buff *skb) |
| { |
| /* This BUG_ON may seem severe, but if we just return then we |
| * are going to dereference garbage. |
| */ |
| BUG_ON(skb_queue_is_last(list, skb)); |
| return skb->next; |
| } |
| |
| /** |
| * skb_queue_prev - return the prev packet in the queue |
| * @list: queue head |
| * @skb: current buffer |
| * |
| * Return the prev packet in @list before @skb. It is only valid to |
| * call this if skb_queue_is_first() evaluates to false. |
| */ |
| static inline struct sk_buff *skb_queue_prev(const struct sk_buff_head *list, |
| const struct sk_buff *skb) |
| { |
| /* This BUG_ON may seem severe, but if we just return then we |
| * are going to dereference garbage. |
| */ |
| BUG_ON(skb_queue_is_first(list, skb)); |
| return skb->prev; |
| } |
| |
| /** |
| * skb_get - reference buffer |
| * @skb: buffer to reference |
| * |
| * Makes another reference to a socket buffer and returns a pointer |
| * to the buffer. |
| */ |
| static inline struct sk_buff *skb_get(struct sk_buff *skb) |
| { |
| refcount_inc(&skb->users); |
| return skb; |
| } |
| |
| /* |
| * If users == 1, we are the only owner and are can avoid redundant |
| * atomic change. |
| */ |
| |
| /** |
| * skb_cloned - is the buffer a clone |
| * @skb: buffer to check |
| * |
| * Returns true if the buffer was generated with skb_clone() and is |
| * one of multiple shared copies of the buffer. Cloned buffers are |
| * shared data so must not be written to under normal circumstances. |
| */ |
| static inline int skb_cloned(const struct sk_buff *skb) |
| { |
| return skb->cloned && |
| (atomic_read(&skb_shinfo(skb)->dataref) & SKB_DATAREF_MASK) != 1; |
| } |
| |
| static inline int skb_unclone(struct sk_buff *skb, gfp_t pri) |
| { |
| might_sleep_if(gfpflags_allow_blocking(pri)); |
| |
| if (skb_cloned(skb)) |
| return pskb_expand_head(skb, 0, 0, pri); |
| |
| return 0; |
| } |
| |
| /** |
| * skb_header_cloned - is the header a clone |
| * @skb: buffer to check |
| * |
| * Returns true if modifying the header part of the buffer requires |
| * the data to be copied. |
| */ |
| static inline int skb_header_cloned(const struct sk_buff *skb) |
| { |
| int dataref; |
| |
| if (!skb->cloned) |
| return 0; |
| |
| dataref = atomic_read(&skb_shinfo(skb)->dataref); |
| dataref = (dataref & SKB_DATAREF_MASK) - (dataref >> SKB_DATAREF_SHIFT); |
| return dataref != 1; |
| } |
| |
| static inline int skb_header_unclone(struct sk_buff *skb, gfp_t pri) |
| { |
| might_sleep_if(gfpflags_allow_blocking(pri)); |
| |
| if (skb_header_cloned(skb)) |
| return pskb_expand_head(skb, 0, 0, pri); |
| |
| return 0; |
| } |
| |
| /** |
| * skb_header_release - release reference to header |
| * @skb: buffer to operate on |
| * |
| * Drop a reference to the header part of the buffer. This is done |
| * by acquiring a payload reference. You must not read from the header |
| * part of skb->data after this. |
| * Note : Check if you can use __skb_header_release() instead. |
| */ |
| static inline void skb_header_release(struct sk_buff *skb) |
| { |
| BUG_ON(skb->nohdr); |
| skb->nohdr = 1; |
| atomic_add(1 << SKB_DATAREF_SHIFT, &skb_shinfo(skb)->dataref); |
| } |
| |
| /** |
| * __skb_header_release - release reference to header |
| * @skb: buffer to operate on |
| * |
| * Variant of skb_header_release() assuming skb is private to caller. |
| * We can avoid one atomic operation. |
| */ |
| static inline void __skb_header_release(struct sk_buff *skb) |
| { |
| skb->nohdr = 1; |
| atomic_set(&skb_shinfo(skb)->dataref, 1 + (1 << SKB_DATAREF_SHIFT)); |
| } |
| |
| |
| /** |
| * skb_shared - is the buffer shared |
| * @skb: buffer to check |
| * |
| * Returns true if more than one person has a reference to this |
| * buffer. |
| */ |
| static inline int skb_shared(const struct sk_buff *skb) |
| { |
| return refcount_read(&skb->users) != 1; |
| } |
| |
| /** |
| * skb_share_check - check if buffer is shared and if so clone it |
| * @skb: buffer to check |
| * @pri: priority for memory allocation |
| * |
| * If the buffer is shared the buffer is cloned and the old copy |
| * drops a reference. A new clone with a single reference is returned. |
| * If the buffer is not shared the original buffer is returned. When |
| * being called from interrupt status or with spinlocks held pri must |
| * be GFP_ATOMIC. |
| * |
| * NULL is returned on a memory allocation failure. |
| */ |
| static inline struct sk_buff *skb_share_check(struct sk_buff *skb, gfp_t pri) |
| { |
| might_sleep_if(gfpflags_allow_blocking(pri)); |
| if (skb_shared(skb)) { |
| struct sk_buff *nskb = skb_clone(skb, pri); |
| |
| if (likely(nskb)) |
| consume_skb(skb); |
| else |
| kfree_skb(skb); |
| skb = nskb; |
| } |
| return skb; |
| } |
| |
| /* |
| * Copy shared buffers into a new sk_buff. We effectively do COW on |
| * packets to handle cases where we have a local reader and forward |
| * and a couple of other messy ones. The normal one is tcpdumping |
| * a packet thats being forwarded. |
| */ |
| |
| /** |
| * skb_unshare - make a copy of a shared buffer |
| * @skb: buffer to check |
| * @pri: priority for memory allocation |
| * |
| * If the socket buffer is a clone then this function creates a new |
| * copy of the data, drops a reference count on the old copy and returns |
| * the new copy with the reference count at 1. If the buffer is not a clone |
| * the original buffer is returned. When called with a spinlock held or |
| * from interrupt state @pri must be %GFP_ATOMIC |
| * |
| * %NULL is returned on a memory allocation failure. |
| */ |
| static inline struct sk_buff *skb_unshare(struct sk_buff *skb, |
| gfp_t pri) |
| { |
| might_sleep_if(gfpflags_allow_blocking(pri)); |
| if (skb_cloned(skb)) { |
| struct sk_buff *nskb = skb_copy(skb, pri); |
| |
| /* Free our shared copy */ |
| if (likely(nskb)) |
| consume_skb(skb); |
| else |
| kfree_skb(skb); |
| skb = nskb; |
| } |
| return skb; |
| } |
| |
| /** |
| * skb_peek - peek at the head of an &sk_buff_head |
| * @list_: list to peek at |
| * |
| * Peek an &sk_buff. Unlike most other operations you _MUST_ |
| * be careful with this one. A peek leaves the buffer on the |
| * list and someone else may run off with it. You must hold |
| * the appropriate locks or have a private queue to do this. |
| * |
| * Returns %NULL for an empty list or a pointer to the head element. |
| * The reference count is not incremented and the reference is therefore |
| * volatile. Use with caution. |
| */ |
| static inline struct sk_buff *skb_peek(const struct sk_buff_head *list_) |
| { |
| struct sk_buff *skb = list_->next; |
| |
| if (skb == (struct sk_buff *)list_) |
| skb = NULL; |
| return skb; |
| } |
| |
| /** |
| * skb_peek_next - peek skb following the given one from a queue |
| * @skb: skb to start from |
| * @list_: list to peek at |
| * |
| * Returns %NULL when the end of the list is met or a pointer to the |
| * next element. The reference count is not incremented and the |
| * reference is therefore volatile. Use with caution. |
| */ |
| static inline struct sk_buff *skb_peek_next(struct sk_buff *skb, |
| const struct sk_buff_head *list_) |
| { |
| struct sk_buff *next = skb->next; |
| |
| if (next == (struct sk_buff *)list_) |
| next = NULL; |
| return next; |
| } |
| |
| /** |
| * skb_peek_tail - peek at the tail of an &sk_buff_head |
| * @list_: list to peek at |
| * |
| * Peek an &sk_buff. Unlike most other operations you _MUST_ |
| * be careful with this one. A peek leaves the buffer on the |
| * list and someone else may run off with it. You must hold |
| * the appropriate locks or have a private queue to do this. |
| * |
| * Returns %NULL for an empty list or a pointer to the tail element. |
| * The reference count is not incremented and the reference is therefore |
| * volatile. Use with caution. |
| */ |
| static inline struct sk_buff *skb_peek_tail(const struct sk_buff_head *list_) |
| { |
| struct sk_buff *skb = list_->prev; |
| |
| if (skb == (struct sk_buff *)list_) |
| skb = NULL; |
| return skb; |
| |
| } |
| |
| /** |
| * skb_queue_len - get queue length |
| * @list_: list to measure |
| * |
| * Return the length of an &sk_buff queue. |
| */ |
| static inline __u32 skb_queue_len(const struct sk_buff_head *list_) |
| { |
| return list_->qlen; |
| } |
| |
| /** |
| * __skb_queue_head_init - initialize non-spinlock portions of sk_buff_head |
| * @list: queue to initialize |
| * |
| * This initializes only the list and queue length aspects of |
| * an sk_buff_head object. This allows to initialize the list |
| * aspects of an sk_buff_head without reinitializing things like |
| * the spinlock. It can also be used for on-stack sk_buff_head |
| * objects where the spinlock is known to not be used. |
| */ |
| static inline void __skb_queue_head_init(struct sk_buff_head *list) |
| { |
| list->prev = list->next = (struct sk_buff *)list; |
| list->qlen = 0; |
| } |
| |
| /* |
| * This function creates a split out lock class for each invocation; |
| * this is needed for now since a whole lot of users of the skb-queue |
| * infrastructure in drivers have different locking usage (in hardirq) |
| * than the networking core (in softirq only). In the long run either the |
| * network layer or drivers should need annotation to consolidate the |
| * main types of usage into 3 classes. |
| */ |
| static inline void skb_queue_head_init(struct sk_buff_head *list) |
| { |
| spin_lock_init(&list->lock); |
| __skb_queue_head_init(list); |
| } |
| |
| static inline void skb_queue_head_init_class(struct sk_buff_head *list, |
| struct lock_class_key *class) |
| { |
| skb_queue_head_init(list); |
| lockdep_set_class(&list->lock, class); |
| } |
| |
| /* |
| * Insert an sk_buff on a list. |
| * |
| * The "__skb_xxxx()" functions are the non-atomic ones that |
| * can only be called with interrupts disabled. |
| */ |
| void skb_insert(struct sk_buff *old, struct sk_buff *newsk, |
| struct sk_buff_head *list); |
| static inline void __skb_insert(struct sk_buff *newsk, |
| struct sk_buff *prev, struct sk_buff *next, |
| struct sk_buff_head *list) |
| { |
| newsk->next = next; |
| newsk->prev = prev; |
| next->prev = prev->next = newsk; |
| list->qlen++; |
| } |
| |
| static inline void __skb_queue_splice(const struct sk_buff_head *list, |
| struct sk_buff *prev, |
| struct sk_buff *next) |
| { |
| struct sk_buff *first = list->next; |
| struct sk_buff *last = list->prev; |
| |
| first->prev = prev; |
| prev->next = first; |
| |
| last->next = next; |
| next->prev = last; |
| } |
| |
| /** |
| * skb_queue_splice - join two skb lists, this is designed for stacks |
| * @list: the new list to add |
| * @head: the place to add it in the first list |
| */ |
| static inline void skb_queue_splice(const struct sk_buff_head *list, |
| struct sk_buff_head *head) |
| { |
| if (!skb_queue_empty(list)) { |
| __skb_queue_splice(list, (struct sk_buff *) head, head->next); |
| head->qlen += list->qlen; |
| } |
| } |
| |
| /** |
| * skb_queue_splice_init - join two skb lists and reinitialise the emptied list |
| * @list: the new list to add |
| * @head: the place to add it in the first list |
| * |
| * The list at @list is reinitialised |
| */ |
| static inline void skb_queue_splice_init(struct sk_buff_head *list, |
| struct sk_buff_head *head) |
| { |
| if (!skb_queue_empty(list)) { |
| __skb_queue_splice(list, (struct sk_buff *) head, head->next); |
| head->qlen += list->qlen; |
| __skb_queue_head_init(list); |
| } |
| } |
| |
| /** |
| * skb_queue_splice_tail - join two skb lists, each list being a queue |
| * @list: the new list to add |
| * @head: the place to add it in the first list |
| */ |
| static inline void skb_queue_splice_tail(const struct sk_buff_head *list, |
| struct sk_buff_head *head) |
| { |
| if (!skb_queue_empty(list)) { |
| __skb_queue_splice(list, head->prev, (struct sk_buff *) head); |
| head->qlen += list->qlen; |
| } |
| } |
| |
| /** |
| * skb_queue_splice_tail_init - join two skb lists and reinitialise the emptied list |
| * @list: the new list to add |
| * @head: the place to add it in the first list |
| * |
| * Each of the lists is a queue. |
| * The list at @list is reinitialised |
| */ |
| static inline void skb_queue_splice_tail_init(struct sk_buff_head *list, |
| struct sk_buff_head *head) |
| { |
| if (!skb_queue_empty(list)) { |
| __skb_queue_splice(list, head->prev, (struct sk_buff *) head); |
| head->qlen += list->qlen; |
| __skb_queue_head_init(list); |
| } |
| } |
| |
| /** |
| * __skb_queue_after - queue a buffer at the list head |
| * @list: list to use |
| * @prev: place after this buffer |
| * @newsk: buffer to queue |
| * |
| * Queue a buffer int the middle of a list. This function takes no locks |
| * and you must therefore hold required locks before calling it. |
| * |
| * A buffer cannot be placed on two lists at the same time. |
| */ |
| static inline void __skb_queue_after(struct sk_buff_head *list, |
| struct sk_buff *prev, |
| struct sk_buff *newsk) |
| { |
| __skb_insert(newsk, prev, prev->next, list); |
| } |
| |
| void skb_append(struct sk_buff *old, struct sk_buff *newsk, |
| struct sk_buff_head *list); |
| |
| static inline void __skb_queue_before(struct sk_buff_head *list, |
| struct sk_buff *next, |
| struct sk_buff *newsk) |
| { |
| __skb_insert(newsk, next->prev, next, list); |
| } |
| |
| /** |
| * __skb_queue_head - queue a buffer at the list head |
| * @list: list to use |
| * @newsk: buffer to queue |
| * |
| * Queue a buffer at the start of a list. This function takes no locks |
| * and you must therefore hold required locks before calling it. |
| * |
| * A buffer cannot be placed on two lists at the same time. |
| */ |
| void skb_queue_head(struct sk_buff_head *list, struct sk_buff *newsk); |
| static inline void __skb_queue_head(struct sk_buff_head *list, |
| struct sk_buff *newsk) |
| { |
| __skb_queue_after(list, (struct sk_buff *)list, newsk); |
| } |
| |
| /** |
| * __skb_queue_tail - queue a buffer at the list tail |
| * @list: list to use |
| * @newsk: buffer to queue |
| * |
| * Queue a buffer at the end of a list. This function takes no locks |
| * and you must therefore hold required locks before calling it. |
| * |
| * A buffer cannot be placed on two lists at the same time. |
| */ |
| void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk); |
| static inline void __skb_queue_tail(struct sk_buff_head *list, |
| struct sk_buff *newsk) |
| { |
| __skb_queue_before(list, (struct sk_buff *)list, newsk); |
| } |
| |
| /* |
| * remove sk_buff from list. _Must_ be called atomically, and with |
| * the list known.. |
| */ |
| void skb_unlink(struct sk_buff *skb, struct sk_buff_head *list); |
| static inline void __skb_unlink(struct sk_buff *skb, struct sk_buff_head *list) |
| { |
| struct sk_buff *next, *prev; |
| |
| list->qlen--; |
| next = skb->next; |
| prev = skb->prev; |
| skb->next = skb->prev = NULL; |
| next->prev = prev; |
| prev->next = next; |
| } |
| |
| /** |
| * __skb_dequeue - remove from the head of the queue |
| * @list: list to dequeue from |
| * |
| * Remove the head of the list. This function does not take any locks |
| * so must be used with appropriate locks held only. The head item is |
| * returned or %NULL if the list is empty. |
| */ |
| struct sk_buff *skb_dequeue(struct sk_buff_head *list); |
| static inline struct sk_buff *__skb_dequeue(struct sk_buff_head *list) |
| { |
| struct sk_buff *skb = skb_peek(list); |
| if (skb) |
| __skb_unlink(skb, list); |
| return skb; |
| } |
| |
| /** |
| * __skb_dequeue_tail - remove from the tail of the queue |
| * @list: list to dequeue from |
| * |
| * Remove the tail of the list. This function does not take any locks |
| * so must be used with appropriate locks held only. The tail item is |
| * returned or %NULL if the list is empty. |
| */ |
| struct sk_buff *skb_dequeue_tail(struct sk_buff_head *list); |
| static inline struct sk_buff *__skb_dequeue_tail(struct sk_buff_head *list) |
| { |
| struct sk_buff *skb = skb_peek_tail(list); |
| if (skb) |
| __skb_unlink(skb, list); |
| return skb; |
| } |
| |
| |
| static inline bool skb_is_nonlinear(const struct sk_buff *skb) |
| { |
| return skb->data_len; |
| } |
| |
| static inline unsigned int skb_headlen(const struct sk_buff *skb) |
| { |
| return skb->len - skb->data_len; |
| } |
| |
| static inline unsigned int __skb_pagelen(const struct sk_buff *skb) |
| { |
| unsigned int i, len = 0; |
| |
| for (i = skb_shinfo(skb)->nr_frags - 1; (int)i >= 0; i--) |
| len += skb_frag_size(&skb_shinfo(skb)->frags[i]); |
| return len; |
| } |
| |
| static inline unsigned int skb_pagelen(const struct sk_buff *skb) |
| { |
| return skb_headlen(skb) + __skb_pagelen(skb); |
| } |
| |
| /** |
| * __skb_fill_page_desc - initialise a paged fragment in an skb |
| * @skb: buffer containing fragment to be initialised |
| * @i: paged fragment index to initialise |
| * @page: the page to use for this fragment |
| * @off: the offset to the data with @page |
| * @size: the length of the data |
| * |
| * Initialises the @i'th fragment of @skb to point to &size bytes at |
| * offset @off within @page. |
| * |
| * Does not take any additional reference on the fragment. |
| */ |
| static inline void __skb_fill_page_desc(struct sk_buff *skb, int i, |
| struct page *page, int off, int size) |
| { |
| skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; |
| |
| /* |
| * Propagate page pfmemalloc to the skb if we can. The problem is |
| * that not all callers have unique ownership of the page but rely |
| * on page_is_pfmemalloc doing the right thing(tm). |
| */ |
| frag->page.p = page; |
| frag->page_offset = off; |
| skb_frag_size_set(frag, size); |
| |
| page = compound_head(page); |
| if (page_is_pfmemalloc(page)) |
| skb->pfmemalloc = true; |
| } |
| |
| /** |
| * skb_fill_page_desc - initialise a paged fragment in an skb |
| * @skb: buffer containing fragment to be initialised |
| * @i: paged fragment index to initialise |
| * @page: the page to use for this fragment |
| * @off: the offset to the data with @page |
| * @size: the length of the data |
| * |
| * As per __skb_fill_page_desc() -- initialises the @i'th fragment of |
| * @skb to point to @size bytes at offset @off within @page. In |
| * addition updates @skb such that @i is the last fragment. |
| * |
| * Does not take any additional reference on the fragment. |
| */ |
| static inline void skb_fill_page_desc(struct sk_buff *skb, int i, |
| struct page *page, int off, int size) |
| { |
| __skb_fill_page_desc(skb, i, page, off, size); |
| skb_shinfo(skb)->nr_frags = i + 1; |
| } |
| |
| void skb_add_rx_frag(struct sk_buff *skb, int i, struct page *page, int off, |
| int size, unsigned int truesize); |
| |
| void skb_coalesce_rx_frag(struct sk_buff *skb, int i, int size, |
| unsigned int truesize); |
| |
| #define SKB_PAGE_ASSERT(skb) BUG_ON(skb_shinfo(skb)->nr_frags) |
| #define SKB_FRAG_ASSERT(skb) BUG_ON(skb_has_frag_list(skb)) |
| #define SKB_LINEAR_ASSERT(skb) BUG_ON(skb_is_nonlinear(skb)) |
| |
| #ifdef NET_SKBUFF_DATA_USES_OFFSET |
| static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb) |
| { |
| return skb->head + skb->tail; |
| } |
| |
| static inline void skb_reset_tail_pointer(struct sk_buff *skb) |
| { |
| skb->tail = skb->data - skb->head; |
| } |
| |
| static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset) |
| { |
| skb_reset_tail_pointer(skb); |
| skb->tail += offset; |
| } |
| |
| #else /* NET_SKBUFF_DATA_USES_OFFSET */ |
| static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb) |
| { |
| return skb->tail; |
| } |
| |
| static inline void skb_reset_tail_pointer(struct sk_buff *skb) |
| { |
| skb->tail = skb->data; |
| } |
| |
| static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset) |
| { |
| skb->tail = skb->data + offset; |
| } |
| |
| #endif /* NET_SKBUFF_DATA_USES_OFFSET */ |
| |
| /* |
| * Add data to an sk_buff |
| */ |
| void *pskb_put(struct sk_buff *skb, struct sk_buff *tail, int len); |
| void *skb_put(struct sk_buff *skb, unsigned int len); |
| static inline void *__skb_put(struct sk_buff *skb, unsigned int len) |
| { |
| void *tmp = skb_tail_pointer(skb); |
| SKB_LINEAR_ASSERT(skb); |
| skb->tail += len; |
| skb->len += len; |
| return tmp; |
| } |
| |
| static inline void *__skb_put_zero(struct sk_buff *skb, unsigned int len) |
| { |
| void *tmp = __skb_put(skb, len); |
| |
| memset(tmp, 0, len); |
| return tmp; |
| } |
| |
| static inline void *__skb_put_data(struct sk_buff *skb, const void *data, |
| unsigned int len) |
| { |
| void *tmp = __skb_put(skb, len); |
| |
| memcpy(tmp, data, len); |
| return tmp; |
| } |
| |
| static inline void __skb_put_u8(struct sk_buff *skb, u8 val) |
| { |
| *(u8 *)__skb_put(skb, 1) = val; |
| } |
| |
| static inline void *skb_put_zero(struct sk_buff *skb, unsigned int len) |
| { |
| void *tmp = skb_put(skb, len); |
| |
| memset(tmp, 0, len); |
| |
| return tmp; |
| } |
| |
| static inline void *skb_put_data(struct sk_buff *skb, const void *data, |
| unsigned int len) |
| { |
| void *tmp = skb_put(skb, len); |
| |
| memcpy(tmp, data, len); |
| |
| return tmp; |
| } |
| |
| static inline void skb_put_u8(struct sk_buff *skb, u8 val) |
| { |
| *(u8 *)skb_put(skb, 1) = val; |
| } |
| |
| void *skb_push(struct sk_buff *skb, unsigned int len); |
| static inline void *__skb_push(struct sk_buff *skb, unsigned int len) |
| { |
| skb->data -= len; |
| skb->len += len; |
| return skb->data; |
| } |
| |
| void *skb_pull(struct sk_buff *skb, unsigned int len); |
| static inline void *__skb_pull(struct sk_buff *skb, unsigned int len) |
| { |
| skb->len -= len; |
| BUG_ON(skb->len < skb->data_len); |
| return skb->data += len; |
| } |
| |
| static inline void *skb_pull_inline(struct sk_buff *skb, unsigned int len) |
| { |
| return unlikely(len > skb->len) ? NULL : __skb_pull(skb, len); |
| } |
| |
| void *__pskb_pull_tail(struct sk_buff *skb, int delta); |
| |
| static inline void *__pskb_pull(struct sk_buff *skb, unsigned int len) |
| { |
| if (len > skb_headlen(skb) && |
| !__pskb_pull_tail(skb, len - skb_headlen(skb))) |
| return NULL; |
| skb->len -= len; |
| return skb->data += len; |
| } |
| |
| static inline void *pskb_pull(struct sk_buff *skb, unsigned int len) |
| { |
| return unlikely(len > skb->len) ? NULL : __pskb_pull(skb, len); |
| } |
| |
| static inline int pskb_may_pull(struct sk_buff *skb, unsigned int len) |
| { |
| if (likely(len <= skb_headlen(skb))) |
| return 1; |
| if (unlikely(len > skb->len)) |
| return 0; |
| return __pskb_pull_tail(skb, len - skb_headlen(skb)) != NULL; |
| } |
| |
| void skb_condense(struct sk_buff *skb); |
| |
| /** |
| * skb_headroom - bytes at buffer head |
| * @skb: buffer to check |
| * |
| * Return the number of bytes of free space at the head of an &sk_buff. |
| */ |
| static inline unsigned int skb_headroom(const struct sk_buff *skb) |
| { |
| return skb->data - skb->head; |
| } |
| |
| /** |
| * skb_tailroom - bytes at buffer end |
| * @skb: buffer to check |
| * |
| * Return the number of bytes of free space at the tail of an sk_buff |
| */ |
| static inline int skb_tailroom(const struct sk_buff *skb) |
| { |
| return skb_is_nonlinear(skb) ? 0 : skb->end - skb->tail; |
| } |
| |
| /** |
| * skb_availroom - bytes at buffer end |
| * @skb: buffer to check |
| * |
| * Return the number of bytes of free space at the tail of an sk_buff |
| * allocated by sk_stream_alloc() |
| */ |
| static inline int skb_availroom(const struct sk_buff *skb) |
| { |
| if (skb_is_nonlinear(skb)) |
| return 0; |
| |
| return skb->end - skb->tail - skb->reserved_tailroom; |
| } |
| |
| /** |
| * skb_reserve - adjust headroom |
| * @skb: buffer to alter |
| * @len: bytes to move |
| * |
| * Increase the headroom of an empty &sk_buff by reducing the tail |
| * room. This is only allowed for an empty buffer. |
| */ |
| static inline void skb_reserve(struct sk_buff *skb, int len) |
| { |
| skb->data += len; |
| skb->tail += len; |
| } |
| |
| /** |
| * skb_tailroom_reserve - adjust reserved_tailroom |
| * @skb: buffer to alter |
| * @mtu: maximum amount of headlen permitted |
| * @needed_tailroom: minimum amount of reserved_tailroom |
| * |
| * Set reserved_tailroom so that headlen can be as large as possible but |
| * not larger than mtu and tailroom cannot be smaller than |
| * needed_tailroom. |
| * The required headroom should already have been reserved before using |
| * this function. |
| */ |
| static inline void skb_tailroom_reserve(struct sk_buff *skb, unsigned int mtu, |
| unsigned int needed_tailroom) |
| { |
| SKB_LINEAR_ASSERT(skb); |
| if (mtu < skb_tailroom(skb) - needed_tailroom) |
| /* use at most mtu */ |
| skb->reserved_tailroom = skb_tailroom(skb) - mtu; |
| else |
| /* use up to all available space */ |
| skb->reserved_tailroom = needed_tailroom; |
| } |
| |
| #define ENCAP_TYPE_ETHER 0 |
| #define ENCAP_TYPE_IPPROTO 1 |
| |
| static inline void skb_set_inner_protocol(struct sk_buff *skb, |
| __be16 protocol) |
| { |
| skb->inner_protocol = protocol; |
| skb->inner_protocol_type = ENCAP_TYPE_ETHER; |
| } |
| |
| static inline void skb_set_inner_ipproto(struct sk_buff *skb, |
| __u8 ipproto) |
| { |
| skb->inner_ipproto = ipproto; |
| skb->inner_protocol_type = ENCAP_TYPE_IPPROTO; |
| } |
| |
| static inline void skb_reset_inner_headers(struct sk_buff *skb) |
| { |
| skb->inner_mac_header = skb->mac_header; |
| skb->inner_network_header = skb->network_header; |
| skb->inner_transport_header = skb->transport_header; |
| } |
| |
| static inline void skb_reset_mac_len(struct sk_buff *skb) |
| { |
| skb->mac_len = skb->network_header - skb->mac_header; |
| } |
| |
| static inline unsigned char *skb_inner_transport_header(const struct sk_buff |
| *skb) |
| { |
| return skb->head + skb->inner_transport_header; |
| } |
| |
| static inline int skb_inner_transport_offset(const struct sk_buff *skb) |
| { |
| return skb_inner_transport_header(skb) - skb->data; |
| } |
| |
| static inline void skb_reset_inner_transport_header(struct sk_buff *skb) |
| { |
| skb->inner_transport_header = skb->data - skb->head; |
| } |
| |
| static inline void skb_set_inner_transport_header(struct sk_buff *skb, |
| const int offset) |
| { |
| skb_reset_inner_transport_header(skb); |
| skb->inner_transport_header += offset; |
| } |
| |
| static inline unsigned char *skb_inner_network_header(const struct sk_buff *skb) |
| { |
| return skb->head + skb->inner_network_header; |
| } |
| |
| static inline void skb_reset_inner_network_header(struct sk_buff *skb) |
| { |
| skb->inner_network_header = skb->data - skb->head; |
| } |
| |
| static inline void skb_set_inner_network_header(struct sk_buff *skb, |
| const int offset) |
| { |
| skb_reset_inner_network_header(skb); |
| skb->inner_network_header += offset; |
| } |
| |
| static inline unsigned char *skb_inner_mac_header(const struct sk_buff *skb) |
| { |
| return skb->head + skb->inner_mac_header; |
| } |
| |
| static inline void skb_reset_inner_mac_header(struct sk_buff *skb) |
| { |
| skb->inner_mac_header = skb->data - skb->head; |
| } |
| |
| static inline void skb_set_inner_mac_header(struct sk_buff *skb, |
| const int offset) |
| { |
| skb_reset_inner_mac_header(skb); |
| skb->inner_mac_header += offset; |
| } |
| static inline bool skb_transport_header_was_set(const struct sk_buff *skb) |
| { |
| return skb->transport_header != (typeof(skb->transport_header))~0U; |
| } |
| |
| static inline unsigned char *skb_transport_header(const struct sk_buff *skb) |
| { |
| return skb->head + skb->transport_header; |
| } |
| |
| static inline void skb_reset_transport_header(struct sk_buff *skb) |
| { |
| skb->transport_header = skb->data - skb->head; |
| } |
| |
| static inline void skb_set_transport_header(struct sk_buff *skb, |
| const int offset) |
| { |
| skb_reset_transport_header(skb); |
| skb->transport_header += offset; |
| } |
| |
| static inline unsigned char *skb_network_header(const struct sk_buff *skb) |
| { |
| return skb->head + skb->network_header; |
| } |
| |
| static inline void skb_reset_network_header(struct sk_buff *skb) |
| { |
| skb->network_header = skb->data - skb->head; |
| } |
| |
| static inline void skb_set_network_header(struct sk_buff *skb, const int offset) |
| { |
| skb_reset_network_header(skb); |
| skb->network_header += offset; |
| } |
| |
| static inline unsigned char *skb_mac_header(const struct sk_buff *skb) |
| { |
| return skb->head + skb->mac_header; |
| } |
| |
| static inline int skb_mac_offset(const struct sk_buff *skb) |
| { |
| return skb_mac_header(skb) - skb->data; |
| } |
| |
| static inline u32 skb_mac_header_len(const struct sk_buff *skb) |
| { |
| return skb->network_header - skb->mac_header; |
| } |
| |
| static inline int skb_mac_header_was_set(const struct sk_buff *skb) |
| { |
| return skb->mac_header != (typeof(skb->mac_header))~0U; |
| } |
| |
| static inline void skb_reset_mac_header(struct sk_buff *skb) |
| { |
| skb->mac_header = skb->data - skb->head; |
| } |
| |
| static inline void skb_set_mac_header(struct sk_buff *skb, const int offset) |
| { |
| skb_reset_mac_header(skb); |
| skb->mac_header += offset; |
| } |
| |
| static inline void skb_pop_mac_header(struct sk_buff *skb) |
| { |
| skb->mac_header = skb->network_header; |
| } |
| |
| static inline void skb_probe_transport_header(struct sk_buff *skb, |
| const int offset_hint) |
| { |
| struct flow_keys keys; |
| |
| if (skb_transport_header_was_set(skb)) |
| return; |
| else if (skb_flow_dissect_flow_keys(skb, &keys, 0)) |
| skb_set_transport_header(skb, keys.control.thoff); |
| else |
| skb_set_transport_header(skb, offset_hint); |
| } |
| |
| static inline void skb_mac_header_rebuild(struct sk_buff *skb) |
| { |
| if (skb_mac_header_was_set(skb)) { |
| const unsigned char *old_mac = skb_mac_header(skb); |
| |
| skb_set_mac_header(skb, -skb->mac_len); |
| memmove(skb_mac_header(skb), old_mac, skb->mac_len); |
| } |
| } |
| |
| static inline int skb_checksum_start_offset(const struct sk_buff *skb) |
| { |
| return skb->csum_start - skb_headroom(skb); |
| } |
| |
| static inline unsigned char *skb_checksum_start(const struct sk_buff *skb) |
| { |
| return skb->head + skb->csum_start; |
| } |
| |
| static inline int skb_transport_offset(const struct sk_buff *skb) |
| { |
| return skb_transport_header(skb) - skb->data; |
| } |
| |
| static inline u32 skb_network_header_len(const struct sk_buff *skb) |
| { |
| return skb->transport_header - skb->network_header; |
| } |
| |
| static inline u32 skb_inner_network_header_len(const struct sk_buff *skb) |
| { |
| return skb->inner_transport_header - skb->inner_network_header; |
| } |
| |
| static inline int skb_network_offset(const struct sk_buff *skb) |
| { |
| return skb_network_header(skb) - skb->data; |
| } |
| |
| static inline int skb_inner_network_offset(const struct sk_buff *skb) |
| { |
| return skb_inner_network_header(skb) - skb->data; |
| } |
| |
| static inline int pskb_network_may_pull(struct sk_buff *skb, unsigned int len) |
| { |
| return pskb_may_pull(skb, skb_network_offset(skb) + len); |
| } |
| |
| /* |
| * CPUs often take a performance hit when accessing unaligned memory |
| * locations. The actual performance hit varies, it can be small if the |
| * hardware handles it or large if we have to take an exception and fix it |
| * in software. |
| * |
| * Since an ethernet header is 14 bytes network drivers often end up with |
| * the IP header at an unaligned offset. The IP header can be aligned by |
| * shifting the start of the packet by 2 bytes. Drivers should do this |
| * with: |
| * |
| * skb_reserve(skb, NET_IP_ALIGN); |
| * |
| * The downside to this alignment of the IP header is that the DMA is now |
| * unaligned. On some architectures the cost of an unaligned DMA is high |
| * and this cost outweighs the gains made by aligning the IP header. |
| * |
| * Since this trade off varies between architectures, we allow NET_IP_ALIGN |
| * to be overridden. |
| */ |
| #ifndef NET_IP_ALIGN |
| #define NET_IP_ALIGN 2 |
| #endif |
| |
| /* |
| * The networking layer reserves some headroom in skb data (via |
| * dev_alloc_skb). This is used to avoid having to reallocate skb data when |
| * the header has to grow. In the default case, if the header has to grow |
| * 32 bytes or less we avoid the reallocation. |
| * |
| * Unfortunately this headroom changes the DMA alignment of the resulting |
| * network packet. As for NET_IP_ALIGN, this unaligned DMA is expensive |
| * on some architectures. An architecture can override this value, |
| * perhaps setting it to a cacheline in size (since that will maintain |
| * cacheline alignment of the DMA). It must be a power of 2. |
| * |
| * Various parts of the networking layer expect at least 32 bytes of |
| * headroom, you should not reduce this. |
| * |
| * Using max(32, L1_CACHE_BYTES) makes sense (especially with RPS) |
| * to reduce average number of cache lines per packet. |
| * get_rps_cpus() for example only access one 64 bytes aligned block : |
| * NET_IP_ALIGN(2) + ethernet_header(14) + IP_header(20/40) + ports(8) |
| */ |
| #ifndef NET_SKB_PAD |
| #define NET_SKB_PAD max(32, L1_CACHE_BYTES) |
| #endif |
| |
| int ___pskb_trim(struct sk_buff *skb, unsigned int len); |
| |
| static inline void __skb_set_length(struct sk_buff *skb, unsigned int len) |
| { |
| if (unlikely(skb_is_nonlinear(skb))) { |
| WARN_ON(1); |
| return; |
| } |
| skb->len = len; |
| skb_set_tail_pointer(skb, len); |
| } |
| |
| static inline void __skb_trim(struct sk_buff *skb, unsigned int len) |
| { |
| __skb_set_length(skb, len); |
| } |
| |
| void skb_trim(struct sk_buff *skb, unsigned int len); |
| |
| static inline int __pskb_trim(struct sk_buff *skb, unsigned int len) |
| { |
| if (skb->data_len) |
| return ___pskb_trim(skb, len); |
| __skb_trim(skb, len); |
| return 0; |
| } |
| |
| static inline int pskb_trim(struct sk_buff *skb, unsigned int len) |
| { |
| return (len < skb->len) ? __pskb_trim(skb, len) : 0; |
| } |
| |
| /** |
| * pskb_trim_unique - remove end from a paged unique (not cloned) buffer |
| * @skb: buffer to alter |
| * @len: new length |
| * |
| * This is identical to pskb_trim except that the caller knows that |
| * the skb is not cloned so we should never get an error due to out- |
| * of-memory. |
| */ |
| static inline void pskb_trim_unique(struct sk_buff *skb, unsigned int len) |
| { |
| int err = pskb_trim(skb, len); |
| BUG_ON(err); |
| } |
| |
| static inline int __skb_grow(struct sk_buff *skb, unsigned int len) |
| { |
| unsigned int diff = len - skb->len; |
| |
| if (skb_tailroom(skb) < diff) { |
| int ret = pskb_expand_head(skb, 0, diff - skb_tailroom(skb), |
| GFP_ATOMIC); |
| if (ret) |
| return ret; |
| } |
| __skb_set_length(skb, len); |
| return 0; |
| } |
| |
| /** |
| * skb_orphan - orphan a buffer |
| * @skb: buffer to orphan |
| * |
| * If a buffer currently has an owner then we call the owner's |
| * destructor function and make the @skb unowned. The buffer continues |
| * to exist but is no longer charged to its former owner. |
| */ |
| static inline void skb_orphan(struct sk_buff *skb) |
| { |
| if (skb->destructor) { |
| skb->destructor(skb); |
| skb->destructor = NULL; |
| skb->sk = NULL; |
| } else { |
| BUG_ON(skb->sk); |
| } |
| } |
| |
| /** |
| * skb_orphan_frags - orphan the frags contained in a buffer |
| * @skb: buffer to orphan frags from |
| * @gfp_mask: allocation mask for replacement pages |
| * |
| * For each frag in the SKB which needs a destructor (i.e. has an |
| * owner) create a copy of that frag and release the original |
| * page by calling the destructor. |
| */ |
| static inline int skb_orphan_frags(struct sk_buff *skb, gfp_t gfp_mask) |
| { |
| if (likely(!skb_zcopy(skb))) |
| return 0; |
| if (skb_uarg(skb)->callback == sock_zerocopy_callback) |
| return 0; |
| return skb_copy_ubufs(skb, gfp_mask); |
| } |
| |
| /* Frags must be orphaned, even if refcounted, if skb might loop to rx path */ |
| static inline int skb_orphan_frags_rx(struct sk_buff *skb, gfp_t gfp_mask) |
| { |
| if (likely(!skb_zcopy(skb))) |
| return 0; |
| return skb_copy_ubufs(skb, gfp_mask); |
| } |
| |
| /** |
| * __skb_queue_purge - empty a list |
| * @list: list to empty |
| * |
| * Delete all buffers on an &sk_buff list. Each buffer is removed from |
| * the list and one reference dropped. This function does not take the |
| * list lock and the caller must hold the relevant locks to use it. |
| */ |
| void skb_queue_purge(struct sk_buff_head *list); |
| static inline void __skb_queue_purge(struct sk_buff_head *list) |
| { |
| struct sk_buff *skb; |
| while ((skb = __skb_dequeue(list)) != NULL) |
| kfree_skb(skb); |
| } |
| |
| void skb_rbtree_purge(struct rb_root *root); |
| |
| void *netdev_alloc_frag(unsigned int fragsz); |
| |
| struct sk_buff *__netdev_alloc_skb(struct net_device *dev, unsigned int length, |
| gfp_t gfp_mask); |
| |
| /** |
| * netdev_alloc_skb - allocate an skbuff for rx on a specific device |
| * @dev: network device to receive on |
| * @length: length to allocate |
| * |
| * Allocate a new &sk_buff and assign it a usage count of one. The |
| * buffer has unspecified headroom built in. Users should allocate |
| * the headroom they think they need without accounting for the |
| * built in space. The built in space is used for optimisations. |
| * |
| * %NULL is returned if there is no free memory. Although this function |
| * allocates memory it can be called from an interrupt. |
| */ |
| static inline struct sk_buff *netdev_alloc_skb(struct net_device *dev, |
| unsigned int length) |
| { |
| return __netdev_alloc_skb(dev, length, GFP_ATOMIC); |
| } |
| |
| /* legacy helper around __netdev_alloc_skb() */ |
| static inline struct sk_buff *__dev_alloc_skb(unsigned int length, |
| gfp_t gfp_mask) |
| { |
| return __netdev_alloc_skb(NULL, length, gfp_mask); |
| } |
| |
| /* legacy helper around netdev_alloc_skb() */ |
| static inline struct sk_buff *dev_alloc_skb(unsigned int length) |
| { |
| return netdev_alloc_skb(NULL, length); |
| } |
| |
| |
| static inline struct sk_buff *__netdev_alloc_skb_ip_align(struct net_device *dev, |
| unsigned int length, gfp_t gfp) |
| { |
| struct sk_buff *skb = __netdev_alloc_skb(dev, length + NET_IP_ALIGN, gfp); |
| |
| if (NET_IP_ALIGN && skb) |
| skb_reserve(skb, NET_IP_ALIGN); |
| return skb; |
| } |
| |
| static inline struct sk_buff *netdev_alloc_skb_ip_align(struct net_device *dev, |
| unsigned int length) |
| { |
| return __netdev_alloc_skb_ip_align(dev, length, GFP_ATOMIC); |
| } |
| |
| static inline void skb_free_frag(void *addr) |
| { |
| page_frag_free(addr); |
| } |
| |
| void *napi_alloc_frag(unsigned int fragsz); |
| struct sk_buff *__napi_alloc_skb(struct napi_struct *napi, |
| unsigned int length, gfp_t gfp_mask); |
| static inline struct sk_buff *napi_alloc_skb(struct napi_struct *napi, |
| unsigned int length) |
| { |
| return __napi_alloc_skb(napi, length, GFP_ATOMIC); |
| } |
| void napi_consume_skb(struct sk_buff *skb, int budget); |
| |
| void __kfree_skb_flush(void); |
| void __kfree_skb_defer(struct sk_buff *skb); |
| |
| /** |
| * __dev_alloc_pages - allocate page for network Rx |
| * @gfp_mask: allocation priority. Set __GFP_NOMEMALLOC if not for network Rx |
| * @order: size of the allocation |
| * |
| * Allocate a new page. |
| * |
| * %NULL is returned if there is no free memory. |
| */ |
| static inline struct page *__dev_alloc_pages(gfp_t gfp_mask, |
| unsigned int order) |
| { |
| /* This piece of code contains several assumptions. |
| * 1. This is for device Rx, therefor a cold page is preferred. |
| * 2. The expectation is the user wants a compound page. |
| * 3. If requesting a order 0 page it will not be compound |
| * due to the check to see if order has a value in prep_new_page |
| * 4. __GFP_MEMALLOC is ignored if __GFP_NOMEMALLOC is set due to |
| * code in gfp_to_alloc_flags that should be enforcing this. |
| */ |
| gfp_mask |= __GFP_COLD | __GFP_COMP | __GFP_MEMALLOC; |
| |
| return alloc_pages_node(NUMA_NO_NODE, gfp_mask, order); |
| } |
| |
| static inline struct page *dev_alloc_pages(unsigned int order) |
| { |
| return __dev_alloc_pages(GFP_ATOMIC | __GFP_NOWARN, order); |
| } |
| |
| /** |
| * __dev_alloc_page - allocate a page for network Rx |
| * @gfp_mask: allocation priority. Set __GFP_NOMEMALLOC if not for network Rx |
| * |
| * Allocate a new page. |
| * |
| * %NULL is returned if there is no free memory. |
| */ |
| static inline struct page *__dev_alloc_page(gfp_t gfp_mask) |
| { |
| return __dev_alloc_pages(gfp_mask, 0); |
| } |
| |
| static inline struct page *dev_alloc_page(void) |
| { |
| return dev_alloc_pages(0); |
| } |
| |
| /** |
| * skb_propagate_pfmemalloc - Propagate pfmemalloc if skb is allocated after RX page |
| * @page: The page that was allocated from skb_alloc_page |
| * @skb: The skb that may need pfmemalloc set |
| */ |
| static inline void skb_propagate_pfmemalloc(struct page *page, |
| struct sk_buff *skb) |
| { |
| if (page_is_pfmemalloc(page)) |
| skb->pfmemalloc = true; |
| } |
| |
| /** |
| * skb_frag_page - retrieve the page referred to by a paged fragment |
| * @frag: the paged fragment |
| * |
| * Returns the &struct page associated with @frag. |
| */ |
| static inline struct page *skb_frag_page(const skb_frag_t *frag) |
| { |
| return frag->page.p; |
| } |
| |
| /** |
| * __skb_frag_ref - take an addition reference on a paged fragment. |
| * @frag: the paged fragment |
| * |
| * Takes an additional reference on the paged fragment @frag. |
| */ |
| static inline void __skb_frag_ref(skb_frag_t *frag) |
| { |
| get_page(skb_frag_page(frag)); |
| } |
| |
| /** |
| * skb_frag_ref - take an addition reference on a paged fragment of an skb. |
| * @skb: the buffer |
| * @f: the fragment offset. |
| * |
| * Takes an additional reference on the @f'th paged fragment of @skb. |
| */ |
| static inline void skb_frag_ref(struct sk_buff *skb, int f) |
| { |
| __skb_frag_ref(&skb_shinfo(skb)->frags[f]); |
| } |
| |
| /** |
| * __skb_frag_unref - release a reference on a paged fragment. |
| * @frag: the paged fragment |
| * |
| * Releases a reference on the paged fragment @frag. |
| */ |
| static inline void __skb_frag_unref(skb_frag_t *frag) |
| { |
| put_page(skb_frag_page(frag)); |
| } |
| |
| /** |
| * skb_frag_unref - release a reference on a paged fragment of an skb. |
| * @skb: the buffer |
| * @f: the fragment offset |
| * |
| * Releases a reference on the @f'th paged fragment of @skb. |
| */ |
| static inline void skb_frag_unref(struct sk_buff *skb, int f) |
| { |
| __skb_frag_unref(&skb_shinfo(skb)->frags[f]); |
| } |
| |
| /** |
| * skb_frag_address - gets the address of the data contained in a paged fragment |
| * @frag: the paged fragment buffer |
| * |
| * Returns the address of the data within @frag. The page must already |
| * be mapped. |
| */ |
| static inline void *skb_frag_address(const skb_frag_t *frag) |
| { |
| return page_address(skb_frag_page(frag)) + frag->page_offset; |
| } |
| |
| /** |
| * skb_frag_address_safe - gets the address of the data contained in a paged fragment |
| * @frag: the paged fragment buffer |
| * |
| * Returns the address of the data within @frag. Checks that the page |
| * is mapped and returns %NULL otherwise. |
| */ |
| static inline void *skb_frag_address_safe(const skb_frag_t *frag) |
| { |
| void *ptr = page_address(skb_frag_page(frag)); |
| if (unlikely(!ptr)) |
| return NULL; |
| |
| return ptr + frag->page_offset; |
| } |
| |
| /** |
| * __skb_frag_set_page - sets the page contained in a paged fragment |
| * @frag: the paged fragment |
| * @page: the page to set |
| * |
| * Sets the fragment @frag to contain @page. |
| */ |
| static inline void __skb_frag_set_page(skb_frag_t *frag, struct page *page) |
| { |
| frag->page.p = page; |
| } |
| |
| /** |
| * skb_frag_set_page - sets the page contained in a paged fragment of an skb |
| * @skb: the buffer |
| * @f: the fragment offset |
| * @page: the page to set |
| * |
| * Sets the @f'th fragment of @skb to contain @page. |
| */ |
| static inline void skb_frag_set_page(struct sk_buff *skb, int f, |
| struct page *page) |
| { |
| __skb_frag_set_page(&skb_shinfo(skb)->frags[f], page); |
| } |
| |
| bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t prio); |
| |
| /** |
| * skb_frag_dma_map - maps a paged fragment via the DMA API |
| * @dev: the device to map the fragment to |
| * @frag: the paged fragment to map |
| * @offset: the offset within the fragment (starting at the |
| * fragment's own offset) |
| * @size: the number of bytes to map |
| * @dir: the direction of the mapping (``PCI_DMA_*``) |
| * |
| * Maps the page associated with @frag to @device. |
| */ |
| static inline dma_addr_t skb_frag_dma_map(struct device *dev, |
| const skb_frag_t *frag, |
| size_t offset, size_t size, |
| enum dma_data_direction dir) |
| { |
| return dma_map_page(dev, skb_frag_page(frag), |
| frag->page_offset + offset, size, dir); |
| } |
| |
| static inline struct sk_buff *pskb_copy(struct sk_buff *skb, |
| gfp_t gfp_mask) |
| { |
| return __pskb_copy(skb, skb_headroom(skb), gfp_mask); |
| } |
| |
| |
| static inline struct sk_buff *pskb_copy_for_clone(struct sk_buff *skb, |
| gfp_t gfp_mask) |
| { |
| return __pskb_copy_fclone(skb, skb_headroom(skb), gfp_mask, true); |
| } |
| |
| |
| /** |
| * skb_clone_writable - is the header of a clone writable |
| * @skb: buffer to check |
| * @len: length up to which to write |
| * |
| * Returns true if modifying the header part of the cloned buffer |
| * does not requires the data to be copied. |
| */ |
| static inline int skb_clone_writable(const struct sk_buff *skb, unsigned int len) |
| { |
| return !skb_header_cloned(skb) && |
| skb_headroom(skb) + len <= skb->hdr_len; |
| } |
| |
| static inline int skb_try_make_writable(struct sk_buff *skb, |
| unsigned int write_len) |
| { |
| return skb_cloned(skb) && !skb_clone_writable(skb, write_len) && |
| pskb_expand_head(skb, 0, 0, GFP_ATOMIC); |
| } |
| |
| static inline int __skb_cow(struct sk_buff *skb, unsigned int headroom, |
| int cloned) |
| { |
| int delta = 0; |
| |
| if (headroom > skb_headroom(skb)) |
| delta = headroom - skb_headroom(skb); |
| |
| if (delta || cloned) |
| return pskb_expand_head(skb, ALIGN(delta, NET_SKB_PAD), 0, |
| GFP_ATOMIC); |
| return 0; |
| } |
| |
| /** |
| * skb_cow - copy header of skb when it is required |
| * @skb: buffer to cow |
| * @headroom: needed headroom |
| * |
| * If the skb passed lacks sufficient headroom or its data part |
| * is shared, data is reallocated. If reallocation fails, an error |
| * is returned and original skb is not changed. |
| * |
| * The result is skb with writable area skb->head...skb->tail |
| * and at least @headroom of space at head. |
| */ |
| static inline int skb_cow(struct sk_buff *skb, unsigned int headroom) |
| { |
| return __skb_cow(skb, headroom, skb_cloned(skb)); |
| } |
| |
| /** |
| * skb_cow_head - skb_cow but only making the head writable |
| * @skb: buffer to cow |
| * @headroom: needed headroom |
| * |
| * This function is identical to skb_cow except that we replace the |
| * skb_cloned check by skb_header_cloned. It should be used when |
| * you only need to push on some header and do not need to modify |
| * the data. |
| */ |
| static inline int skb_cow_head(struct sk_buff *skb, unsigned int headroom) |
| { |
| return __skb_cow(skb, headroom, skb_header_cloned(skb)); |
| } |
| |
| /** |
| * skb_padto - pad an skbuff up to a minimal size |
| * @skb: buffer to pad |
| * @len: minimal length |
| * |
| * Pads up a buffer to ensure the trailing bytes exist and are |
| * blanked. If the buffer already contains sufficient data it |
| * is untouched. Otherwise it is extended. Returns zero on |
| * success. The skb is freed on error. |
| */ |
| static inline int skb_padto(struct sk_buff *skb, unsigned int len) |
| { |
| unsigned int size = skb->len; |
| if (likely(size >= len)) |
| return 0; |
| return skb_pad(skb, len - size); |
| } |
| |
| /** |
| * skb_put_padto - increase size and pad an skbuff up to a minimal size |
| * @skb: buffer to pad |
| * @len: minimal length |
| * @free_on_error: free buffer on error |
| * |
| * Pads up a buffer to ensure the trailing bytes exist and are |
| * blanked. If the buffer already contains sufficient data it |
| * is untouched. Otherwise it is extended. Returns zero on |
| * success. The skb is freed on error if @free_on_error is true. |
| */ |
| static inline int __skb_put_padto(struct sk_buff *skb, unsigned int len, |
| bool free_on_error) |
| { |
| unsigned int size = skb->len; |
| |
| if (unlikely(size < len)) { |
| len -= size; |
| if (__skb_pad(skb, len, free_on_error)) |
| return -ENOMEM; |
| __skb_put(skb, len); |
| } |
| return 0; |
| } |
| |
| /** |
| * skb_put_padto - increase size and pad an skbuff up to a minimal size |
| * @skb: buffer to pad |
| * @len: minimal length |
| * |
| * Pads up a buffer to ensure the trailing bytes exist and are |
| * blanked. If the buffer already contains sufficient data it |
| * is untouched. Otherwise it is extended. Returns zero on |
| * success. The skb is freed on error. |
| */ |
| static inline int skb_put_padto(struct sk_buff *skb, unsigned int len) |
| { |
| return __skb_put_padto(skb, len, true); |
| } |
| |
| static inline int skb_add_data(struct sk_buff *skb, |
| struct iov_iter *from, int copy) |
| { |
| const int off = skb->len; |
| |
| if (skb->ip_summed == CHECKSUM_NONE) { |
| __wsum csum = 0; |
| if (csum_and_copy_from_iter_full(skb_put(skb, copy), copy, |
| &csum, from)) { |
| skb->csum = csum_block_add(skb->csum, csum, off); |
| return 0; |
| } |
| } else if (copy_from_iter_full(skb_put(skb, copy), copy, from)) |
| return 0; |
| |
| __skb_trim(skb, off); |
| return -EFAULT; |
| } |
| |
| static inline bool skb_can_coalesce(struct sk_buff *skb, int i, |
| const struct page *page, int off) |
| { |
| if (skb_zcopy(skb)) |
| return false; |
| if (i) { |
| const struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[i - 1]; |
| |
| return page == skb_frag_page(frag) && |
| off == frag->page_offset + skb_frag_size(frag); |
| } |
| return false; |
| } |
| |
| static inline int __skb_linearize(struct sk_buff *skb) |
| { |
| return __pskb_pull_tail(skb, skb->data_len) ? 0 : -ENOMEM; |
| } |
| |
| /** |
| * skb_linearize - convert paged skb to linear one |
| * @skb: buffer to linarize |
| * |
| * If there is no free memory -ENOMEM is returned, otherwise zero |
| * is returned and the old skb data released. |
| */ |
| static inline int skb_linearize(struct sk_buff *skb) |
| { |
| return skb_is_nonlinear(skb) ? __skb_linearize(skb) : 0; |
| } |
| |
| /** |
| * skb_has_shared_frag - can any frag be overwritten |
| * @skb: buffer to test |
| * |
| * Return true if the skb has at least one frag that might be modified |
| * by an external entity (as in vmsplice()/sendfile()) |
| */ |
| static inline bool skb_has_shared_frag(const struct sk_buff *skb) |
| { |
| return skb_is_nonlinear(skb) && |
| skb_shinfo(skb)->tx_flags & SKBTX_SHARED_FRAG; |
| } |
| |
| /** |
| * skb_linearize_cow - make sure skb is linear and writable |
| * @skb: buffer to process |
| * |
| * If there is no free memory -ENOMEM is returned, otherwise zero |
| * is returned and the old skb data released. |
| */ |
| static inline int skb_linearize_cow(struct sk_buff *skb) |
| { |
| return skb_is_nonlinear(skb) || skb_cloned(skb) ? |
| __skb_linearize(skb) : 0; |
| } |
| |
| static __always_inline void |
| __skb_postpull_rcsum(struct sk_buff *skb, const void *start, unsigned int len, |
| unsigned int off) |
| { |
| if (skb->ip_summed == CHECKSUM_COMPLETE) |
| skb->csum = csum_block_sub(skb->csum, |
| csum_partial(start, len, 0), off); |
| else if (skb->ip_summed == CHECKSUM_PARTIAL && |
| skb_checksum_start_offset(skb) < 0) |
| skb->ip_summed = CHECKSUM_NONE; |
| } |
| |
| /** |
| * skb_postpull_rcsum - update checksum for received skb after pull |
| * @skb: buffer to update |
| * @start: start of data before pull |
| * @len: length of data pulled |
| * |
| * After doing a pull on a received packet, you need to call this to |
| * update the CHECKSUM_COMPLETE checksum, or set ip_summed to |
| * CHECKSUM_NONE so that it can be recomputed from scratch. |
| */ |
| static inline void skb_postpull_rcsum(struct sk_buff *skb, |
| const void *start, unsigned int len) |
| { |
| __skb_postpull_rcsum(skb, start, len, 0); |
| } |
| |
| static __always_inline void |
| __skb_postpush_rcsum(struct sk_buff *skb, const void *start, unsigned int len, |
| unsigned int off) |
| { |
| if (skb->ip_summed == CHECKSUM_COMPLETE) |
| skb->csum = csum_block_add(skb->csum, |
| csum_partial(start, len, 0), off); |
| } |
| |
| /** |
| * skb_postpush_rcsum - update checksum for received skb after push |
| * @skb: buffer to update |
| * @start: start of data after push |
| * @len: length of data pushed |
| * |
| * After doing a push on a received packet, you need to call this to |
| * update the CHECKSUM_COMPLETE checksum. |
| */ |
| static inline void skb_postpush_rcsum(struct sk_buff *skb, |
| const void *start, unsigned int len) |
| { |
| __skb_postpush_rcsum(skb, start, len, 0); |
| } |
| |
| void *skb_pull_rcsum(struct sk_buff *skb, unsigned int len); |
| |
| /** |
| * skb_push_rcsum - push skb and update receive checksum |
| * @skb: buffer to update |
| * @len: length of data pulled |
| * |
| * This function performs an skb_push on the packet and updates |
| * the CHECKSUM_COMPLETE checksum. It should be used on |
| * receive path processing instead of skb_push unless you know |
| * that the checksum difference is zero (e.g., a valid IP header) |
| * or you are setting ip_summed to CHECKSUM_NONE. |
| */ |
| static inline void *skb_push_rcsum(struct sk_buff *skb, unsigned int len) |
| { |
| skb_push(skb, len); |
| skb_postpush_rcsum(skb, skb->data, len); |
| return skb->data; |
| } |
| |
| /** |
| * pskb_trim_rcsum - trim received skb and update checksum |
| * @skb: buffer to trim |
| * @len: new length |
| * |
| * This is exactly the same as pskb_trim except that it ensures the |
| * checksum of received packets are still valid after the operation. |
| */ |
| |
| static inline int pskb_trim_rcsum(struct sk_buff *skb, unsigned int len) |
| { |
| if (likely(len >= skb->len)) |
| return 0; |
| if (skb->ip_summed == CHECKSUM_COMPLETE) |
| skb->ip_summed = CHECKSUM_NONE; |
| return __pskb_trim(skb, len); |
| } |
| |
| static inline int __skb_trim_rcsum(struct sk_buff *skb, unsigned int len) |
| { |
| if (skb->ip_summed == CHECKSUM_COMPLETE) |
| skb->ip_summed = CHECKSUM_NONE; |
| __skb_trim(skb, len); |
| return 0; |
| } |
| |
| static inline int __skb_grow_rcsum(struct sk_buff *skb, unsigned int len) |
| { |
| if (skb->ip_summed == CHECKSUM_COMPLETE) |
| skb->ip_summed = CHECKSUM_NONE; |
| return __skb_grow(skb, len); |
| } |
| |
| #define skb_queue_walk(queue, skb) \ |
| for (skb = (queue)->next; \ |
| skb != (struct sk_buff *)(queue); \ |
| skb = skb->next) |
| |
| #define skb_queue_walk_safe(queue, skb, tmp) \ |
| for (skb = (queue)->next, tmp = skb->next; \ |
| skb != (struct sk_buff *)(queue); \ |
| skb = tmp, tmp = skb->next) |
| |
| #define skb_queue_walk_from(queue, skb) \ |
| for (; skb != (struct sk_buff *)(queue); \ |
| skb = skb->next) |
| |
| #define skb_queue_walk_from_safe(queue, skb, tmp) \ |
| for (tmp = skb->next; \ |
| skb != (struct sk_buff *)(queue); \ |
| skb = tmp, tmp = skb->next) |
| |
| #define skb_queue_reverse_walk(queue, skb) \ |
| for (skb = (queue)->prev; \ |
| skb != (struct sk_buff *)(queue); \ |
| skb = skb->prev) |
| |
| #define skb_queue_reverse_walk_safe(queue, skb, tmp) \ |
| for (skb = (queue)->prev, tmp = skb->prev; \ |
| skb != (struct sk_buff *)(queue); \ |
| skb = tmp, tmp = skb->prev) |
| |
| #define skb_queue_reverse_walk_from_safe(queue, skb, tmp) \ |
| for (tmp = skb->prev; \ |
| skb != (struct sk_buff *)(queue); \ |
| skb = tmp, tmp = skb->prev) |
| |
| static inline bool skb_has_frag_list(const struct sk_buff *skb) |
| { |
| return skb_shinfo(skb)->frag_list != NULL; |
| } |
| |
| static inline void skb_frag_list_init(struct sk_buff *skb) |
| { |
| skb_shinfo(skb)->frag_list = NULL; |
| } |
| |
| #define skb_walk_frags(skb, iter) \ |
| for (iter = skb_shinfo(skb)->frag_list; iter; iter = iter->next) |
| |
| |
| int __skb_wait_for_more_packets(struct sock *sk, int *err, long *timeo_p, |
| const struct sk_buff *skb); |
| struct sk_buff *__skb_try_recv_from_queue(struct sock *sk, |
| struct sk_buff_head *queue, |
| unsigned int flags, |
| void (*destructor)(struct sock *sk, |
| struct sk_buff *skb), |
| int *peeked, int *off, int *err, |
| struct sk_buff **last); |
| struct sk_buff *__skb_try_recv_datagram(struct sock *sk, unsigned flags, |
| void (*destructor)(struct sock *sk, |
| struct sk_buff *skb), |
| int *peeked, int *off, int *err, |
| struct sk_buff **last); |
| struct sk_buff *__skb_recv_datagram(struct sock *sk, unsigned flags, |
| void (*destructor)(struct sock *sk, |
| struct sk_buff *skb), |
| int *peeked, int *off, int *err); |
| struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags, int noblock, |
| int *err); |
| unsigned int datagram_poll(struct file *file, struct socket *sock, |
| struct poll_table_struct *wait); |
| int skb_copy_datagram_iter(const struct sk_buff *from, int offset, |
| struct iov_iter *to, int size); |
| static inline int skb_copy_datagram_msg(const struct sk_buff *from, int offset, |
| struct msghdr *msg, int size) |
| { |
| return skb_copy_datagram_iter(from, offset, &msg->msg_iter, size); |
| } |
| int skb_copy_and_csum_datagram_msg(struct sk_buff *skb, int hlen, |
| struct msghdr *msg); |
| int skb_copy_datagram_from_iter(struct sk_buff *skb, int offset, |
| struct iov_iter *from, int len); |
| int zerocopy_sg_from_iter(struct sk_buff *skb, struct iov_iter *frm); |
| void skb_free_datagram(struct sock *sk, struct sk_buff *skb); |
| void __skb_free_datagram_locked(struct sock *sk, struct sk_buff *skb, int len); |
| static inline void skb_free_datagram_locked(struct sock *sk, |
| struct sk_buff *skb) |
| { |
| __skb_free_datagram_locked(sk, skb, 0); |
| } |
| int skb_kill_datagram(struct sock *sk, struct sk_buff *skb, unsigned int flags); |
| int skb_copy_bits(const struct sk_buff *skb, int offset, void *to, int len); |
| int skb_store_bits(struct sk_buff *skb, int offset, const void *from, int len); |
| __wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset, u8 *to, |
| int len, __wsum csum); |
| int skb_splice_bits(struct sk_buff *skb, struct sock *sk, unsigned int offset, |
| struct pipe_inode_info *pipe, unsigned int len, |
| unsigned int flags); |
| int skb_send_sock_locked(struct sock *sk, struct sk_buff *skb, int offset, |
| int len); |
| int skb_send_sock(struct sock *sk, struct sk_buff *skb, int offset, int len); |
| void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to); |
| unsigned int skb_zerocopy_headlen(const struct sk_buff *from); |
| int skb_zerocopy(struct sk_buff *to, struct sk_buff *from, |
| int len, int hlen); |
| void skb_split(struct sk_buff *skb, struct sk_buff *skb1, const u32 len); |
| int skb_shift(struct sk_buff *tgt, struct sk_buff *skb, int shiftlen); |
| void skb_scrub_packet(struct sk_buff *skb, bool xnet); |
| unsigned int skb_gso_transport_seglen(const struct sk_buff *skb); |
| bool skb_gso_validate_mtu(const struct sk_buff *skb, unsigned int mtu); |
| struct sk_buff *skb_segment(struct sk_buff *skb, netdev_features_t features); |
| struct sk_buff *skb_vlan_untag(struct sk_buff *skb); |
| int skb_ensure_writable(struct sk_buff *skb, int write_len); |
| int __skb_vlan_pop(struct sk_buff *skb, u16 *vlan_tci); |
| int skb_vlan_pop(struct sk_buff *skb); |
| int skb_vlan_push(struct sk_buff *skb, __be16 vlan_proto, u16 vlan_tci); |
| struct sk_buff |