4702 lines
132 KiB
C
4702 lines
132 KiB
C
/* SPDX-License-Identifier: GPL-2.0-or-later */
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/*
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* Definitions for the 'struct sk_buff' memory handlers.
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*
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* Authors:
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* Alan Cox, <gw4pts@gw4pts.ampr.org>
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* Florian La Roche, <rzsfl@rz.uni-sb.de>
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*/
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#ifndef _LINUX_SKBUFF_H
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#define _LINUX_SKBUFF_H
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#include <linux/kernel.h>
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#include <linux/compiler.h>
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#include <linux/time.h>
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#include <linux/bug.h>
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#include <linux/bvec.h>
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#include <linux/cache.h>
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#include <linux/rbtree.h>
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#include <linux/socket.h>
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#include <linux/refcount.h>
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#include <linux/atomic.h>
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#include <asm/types.h>
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#include <linux/spinlock.h>
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#include <linux/net.h>
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#include <linux/textsearch.h>
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#include <net/checksum.h>
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#include <linux/rcupdate.h>
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#include <linux/hrtimer.h>
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#include <linux/dma-mapping.h>
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#include <linux/netdev_features.h>
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#include <linux/sched.h>
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#include <linux/sched/clock.h>
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#include <net/flow_dissector.h>
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#include <linux/splice.h>
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#include <linux/in6.h>
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#include <linux/if_packet.h>
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#include <net/flow.h>
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#if IS_ENABLED(CONFIG_NF_CONNTRACK)
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#include <linux/netfilter/nf_conntrack_common.h>
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#endif
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/* The interface for checksum offload between the stack and networking drivers
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* is as follows...
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*
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* A. IP checksum related features
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*
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* Drivers advertise checksum offload capabilities in the features of a device.
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* From the stack's point of view these are capabilities offered by the driver.
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* A driver typically only advertises features that it is capable of offloading
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* to its device.
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*
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* The checksum related features are:
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*
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* NETIF_F_HW_CSUM - The driver (or its device) is able to compute one
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* IP (one's complement) checksum for any combination
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* of protocols or protocol layering. The checksum is
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* computed and set in a packet per the CHECKSUM_PARTIAL
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* interface (see below).
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*
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* NETIF_F_IP_CSUM - Driver (device) is only able to checksum plain
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* TCP or UDP packets over IPv4. These are specifically
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* unencapsulated packets of the form IPv4|TCP or
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* IPv4|UDP where the Protocol field in the IPv4 header
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* is TCP or UDP. The IPv4 header may contain IP options.
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* This feature cannot be set in features for a device
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* with NETIF_F_HW_CSUM also set. This feature is being
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* DEPRECATED (see below).
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*
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* NETIF_F_IPV6_CSUM - Driver (device) is only able to checksum plain
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* TCP or UDP packets over IPv6. These are specifically
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* unencapsulated packets of the form IPv6|TCP or
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* IPv6|UDP where the Next Header field in the IPv6
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* header is either TCP or UDP. IPv6 extension headers
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* are not supported with this feature. This feature
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* cannot be set in features for a device with
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* NETIF_F_HW_CSUM also set. This feature is being
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* DEPRECATED (see below).
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*
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* NETIF_F_RXCSUM - Driver (device) performs receive checksum offload.
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* This flag is only used to disable the RX checksum
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* feature for a device. The stack will accept receive
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* checksum indication in packets received on a device
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* regardless of whether NETIF_F_RXCSUM is set.
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*
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* B. Checksumming of received packets by device. Indication of checksum
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* verification is set in skb->ip_summed. Possible values are:
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*
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* CHECKSUM_NONE:
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*
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* Device did not checksum this packet e.g. due to lack of capabilities.
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* The packet contains full (though not verified) checksum in packet but
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* not in skb->csum. Thus, skb->csum is undefined in this case.
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*
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* CHECKSUM_UNNECESSARY:
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*
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* The hardware you're dealing with doesn't calculate the full checksum
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* (as in CHECKSUM_COMPLETE), but it does parse headers and verify checksums
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* for specific protocols. For such packets it will set CHECKSUM_UNNECESSARY
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* if their checksums are okay. skb->csum is still undefined in this case
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* though. A driver or device must never modify the checksum field in the
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* packet even if checksum is verified.
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*
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* CHECKSUM_UNNECESSARY is applicable to following protocols:
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* TCP: IPv6 and IPv4.
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* UDP: IPv4 and IPv6. A device may apply CHECKSUM_UNNECESSARY to a
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* zero UDP checksum for either IPv4 or IPv6, the networking stack
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* may perform further validation in this case.
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* GRE: only if the checksum is present in the header.
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* SCTP: indicates the CRC in SCTP header has been validated.
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* FCOE: indicates the CRC in FC frame has been validated.
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*
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* skb->csum_level indicates the number of consecutive checksums found in
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* the packet minus one that have been verified as CHECKSUM_UNNECESSARY.
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* For instance if a device receives an IPv6->UDP->GRE->IPv4->TCP packet
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* and a device is able to verify the checksums for UDP (possibly zero),
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* GRE (checksum flag is set) and TCP, skb->csum_level would be set to
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* two. If the device were only able to verify the UDP checksum and not
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* GRE, either because it doesn't support GRE checksum or because GRE
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* checksum is bad, skb->csum_level would be set to zero (TCP checksum is
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* not considered in this case).
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*
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* CHECKSUM_COMPLETE:
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*
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* This is the most generic way. The device supplied checksum of the _whole_
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* packet as seen by netif_rx() and fills in skb->csum. This means the
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* hardware doesn't need to parse L3/L4 headers to implement this.
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*
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* Notes:
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* - Even if device supports only some protocols, but is able to produce
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* skb->csum, it MUST use CHECKSUM_COMPLETE, not CHECKSUM_UNNECESSARY.
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* - CHECKSUM_COMPLETE is not applicable to SCTP and FCoE protocols.
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*
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* CHECKSUM_PARTIAL:
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*
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* A checksum is set up to be offloaded to a device as described in the
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* output description for CHECKSUM_PARTIAL. This may occur on a packet
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* received directly from another Linux OS, e.g., a virtualized Linux kernel
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* on the same host, or it may be set in the input path in GRO or remote
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* checksum offload. For the purposes of checksum verification, the checksum
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* referred to by skb->csum_start + skb->csum_offset and any preceding
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* checksums in the packet are considered verified. Any checksums in the
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* packet that are after the checksum being offloaded are not considered to
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* be verified.
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*
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* C. Checksumming on transmit for non-GSO. The stack requests checksum offload
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* in the skb->ip_summed for a packet. Values are:
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*
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* CHECKSUM_PARTIAL:
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*
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* The driver is required to checksum the packet as seen by hard_start_xmit()
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* from skb->csum_start up to the end, and to record/write the checksum at
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* offset skb->csum_start + skb->csum_offset. A driver may verify that the
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* csum_start and csum_offset values are valid values given the length and
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* offset of the packet, but it should not attempt to validate that the
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* checksum refers to a legitimate transport layer checksum -- it is the
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* purview of the stack to validate that csum_start and csum_offset are set
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* correctly.
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*
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* When the stack requests checksum offload for a packet, the driver MUST
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* ensure that the checksum is set correctly. A driver can either offload the
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* checksum calculation to the device, or call skb_checksum_help (in the case
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* that the device does not support offload for a particular checksum).
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*
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* NETIF_F_IP_CSUM and NETIF_F_IPV6_CSUM are being deprecated in favor of
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* NETIF_F_HW_CSUM. New devices should use NETIF_F_HW_CSUM to indicate
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* checksum offload capability.
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* skb_csum_hwoffload_help() can be called to resolve CHECKSUM_PARTIAL based
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* on network device checksumming capabilities: if a packet does not match
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* them, skb_checksum_help or skb_crc32c_help (depending on the value of
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* csum_not_inet, see item D.) is called to resolve the checksum.
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*
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* CHECKSUM_NONE:
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*
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* The skb was already checksummed by the protocol, or a checksum is not
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* required.
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*
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* CHECKSUM_UNNECESSARY:
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*
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* This has the same meaning as CHECKSUM_NONE for checksum offload on
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* output.
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*
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* CHECKSUM_COMPLETE:
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* Not used in checksum output. If a driver observes a packet with this value
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* set in skbuff, it should treat the packet as if CHECKSUM_NONE were set.
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*
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* D. Non-IP checksum (CRC) offloads
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*
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* NETIF_F_SCTP_CRC - This feature indicates that a device is capable of
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* offloading the SCTP CRC in a packet. To perform this offload the stack
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* will set csum_start and csum_offset accordingly, set ip_summed to
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* CHECKSUM_PARTIAL and set csum_not_inet to 1, to provide an indication in
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* the skbuff that the CHECKSUM_PARTIAL refers to CRC32c.
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* A driver that supports both IP checksum offload and SCTP CRC32c offload
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* must verify which offload is configured for a packet by testing the
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* value of skb->csum_not_inet; skb_crc32c_csum_help is provided to resolve
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* CHECKSUM_PARTIAL on skbs where csum_not_inet is set to 1.
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*
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* NETIF_F_FCOE_CRC - This feature indicates that a device is capable of
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* offloading the FCOE CRC in a packet. To perform this offload the stack
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* will set ip_summed to CHECKSUM_PARTIAL and set csum_start and csum_offset
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* accordingly. Note that there is no indication in the skbuff that the
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* CHECKSUM_PARTIAL refers to an FCOE checksum, so a driver that supports
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* both IP checksum offload and FCOE CRC offload must verify which offload
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* is configured for a packet, presumably by inspecting packet headers.
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*
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* E. Checksumming on output with GSO.
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*
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* In the case of a GSO packet (skb_is_gso(skb) is true), checksum offload
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* is implied by the SKB_GSO_* flags in gso_type. Most obviously, if the
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* gso_type is SKB_GSO_TCPV4 or SKB_GSO_TCPV6, TCP checksum offload as
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* part of the GSO operation is implied. If a checksum is being offloaded
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* with GSO then ip_summed is CHECKSUM_PARTIAL, and both csum_start and
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* csum_offset are set to refer to the outermost checksum being offloaded
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* (two offloaded checksums are possible with UDP encapsulation).
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*/
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/* Don't change this without changing skb_csum_unnecessary! */
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#define CHECKSUM_NONE 0
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#define CHECKSUM_UNNECESSARY 1
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#define CHECKSUM_COMPLETE 2
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#define CHECKSUM_PARTIAL 3
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/* Maximum value in skb->csum_level */
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#define SKB_MAX_CSUM_LEVEL 3
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#define SKB_DATA_ALIGN(X) ALIGN(X, SMP_CACHE_BYTES)
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#define SKB_WITH_OVERHEAD(X) \
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((X) - SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
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#define SKB_MAX_ORDER(X, ORDER) \
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SKB_WITH_OVERHEAD((PAGE_SIZE << (ORDER)) - (X))
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#define SKB_MAX_HEAD(X) (SKB_MAX_ORDER((X), 0))
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#define SKB_MAX_ALLOC (SKB_MAX_ORDER(0, 2))
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/* return minimum truesize of one skb containing X bytes of data */
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#define SKB_TRUESIZE(X) ((X) + \
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SKB_DATA_ALIGN(sizeof(struct sk_buff)) + \
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SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
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struct ahash_request;
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struct net_device;
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struct scatterlist;
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struct pipe_inode_info;
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struct iov_iter;
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struct napi_struct;
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struct bpf_prog;
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union bpf_attr;
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struct skb_ext;
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#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
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struct nf_bridge_info {
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enum {
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BRNF_PROTO_UNCHANGED,
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BRNF_PROTO_8021Q,
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BRNF_PROTO_PPPOE
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} orig_proto:8;
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u8 pkt_otherhost:1;
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u8 in_prerouting:1;
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u8 bridged_dnat:1;
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__u16 frag_max_size;
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struct net_device *physindev;
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/* always valid & non-NULL from FORWARD on, for physdev match */
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struct net_device *physoutdev;
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union {
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/* prerouting: detect dnat in orig/reply direction */
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__be32 ipv4_daddr;
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struct in6_addr ipv6_daddr;
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/* after prerouting + nat detected: store original source
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* mac since neigh resolution overwrites it, only used while
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* skb is out in neigh layer.
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*/
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char neigh_header[8];
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};
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};
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#endif
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#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
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/* Chain in tc_skb_ext will be used to share the tc chain with
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* ovs recirc_id. It will be set to the current chain by tc
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* and read by ovs to recirc_id.
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*/
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struct tc_skb_ext {
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__u32 chain;
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__u16 mru;
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bool post_ct;
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};
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#endif
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struct sk_buff_head {
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/* These two members must be first. */
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struct sk_buff *next;
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struct sk_buff *prev;
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__u32 qlen;
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spinlock_t lock;
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};
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struct sk_buff;
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/* To allow 64K frame to be packed as single skb without frag_list we
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* require 64K/PAGE_SIZE pages plus 1 additional page to allow for
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* buffers which do not start on a page boundary.
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*
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* Since GRO uses frags we allocate at least 16 regardless of page
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* size.
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*/
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#if (65536/PAGE_SIZE + 1) < 16
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#define MAX_SKB_FRAGS 16UL
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#else
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#define MAX_SKB_FRAGS (65536/PAGE_SIZE + 1)
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#endif
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extern int sysctl_max_skb_frags;
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/* Set skb_shinfo(skb)->gso_size to this in case you want skb_segment to
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* segment using its current segmentation instead.
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*/
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#define GSO_BY_FRAGS 0xFFFF
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typedef struct bio_vec skb_frag_t;
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/**
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* skb_frag_size() - Returns the size of a skb fragment
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* @frag: skb fragment
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*/
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static inline unsigned int skb_frag_size(const skb_frag_t *frag)
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{
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return frag->bv_len;
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}
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/**
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* skb_frag_size_set() - Sets the size of a skb fragment
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* @frag: skb fragment
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* @size: size of fragment
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*/
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static inline void skb_frag_size_set(skb_frag_t *frag, unsigned int size)
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{
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frag->bv_len = size;
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}
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/**
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* skb_frag_size_add() - Increments the size of a skb fragment by @delta
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* @frag: skb fragment
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* @delta: value to add
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*/
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static inline void skb_frag_size_add(skb_frag_t *frag, int delta)
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{
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frag->bv_len += delta;
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}
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/**
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* skb_frag_size_sub() - Decrements the size of a skb fragment by @delta
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* @frag: skb fragment
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* @delta: value to subtract
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*/
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static inline void skb_frag_size_sub(skb_frag_t *frag, int delta)
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{
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frag->bv_len -= delta;
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}
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/**
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* skb_frag_must_loop - Test if %p is a high memory page
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* @p: fragment's page
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*/
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static inline bool skb_frag_must_loop(struct page *p)
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{
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#if defined(CONFIG_HIGHMEM)
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if (IS_ENABLED(CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP) || PageHighMem(p))
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return true;
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#endif
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return false;
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}
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/**
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* skb_frag_foreach_page - loop over pages in a fragment
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*
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* @f: skb frag to operate on
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* @f_off: offset from start of f->bv_page
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* @f_len: length from f_off to loop over
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* @p: (temp var) current page
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* @p_off: (temp var) offset from start of current page,
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* non-zero only on first page.
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* @p_len: (temp var) length in current page,
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* < PAGE_SIZE only on first and last page.
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* @copied: (temp var) length so far, excluding current p_len.
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*
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* A fragment can hold a compound page, in which case per-page
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* operations, notably kmap_atomic, must be called for each
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* regular page.
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*/
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#define skb_frag_foreach_page(f, f_off, f_len, p, p_off, p_len, copied) \
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for (p = skb_frag_page(f) + ((f_off) >> PAGE_SHIFT), \
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p_off = (f_off) & (PAGE_SIZE - 1), \
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p_len = skb_frag_must_loop(p) ? \
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min_t(u32, f_len, PAGE_SIZE - p_off) : f_len, \
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copied = 0; \
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copied < f_len; \
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copied += p_len, p++, p_off = 0, \
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p_len = min_t(u32, f_len - copied, PAGE_SIZE)) \
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#define HAVE_HW_TIME_STAMP
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/**
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* struct skb_shared_hwtstamps - hardware time stamps
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* @hwtstamp: hardware time stamp transformed into duration
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* since arbitrary point in time
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*
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* Software time stamps generated by ktime_get_real() are stored in
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* skb->tstamp.
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*
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* hwtstamps can only be compared against other hwtstamps from
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* the same device.
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*
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* This structure is attached to packets as part of the
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* &skb_shared_info. Use skb_hwtstamps() to get a pointer.
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*/
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struct skb_shared_hwtstamps {
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ktime_t hwtstamp;
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};
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/* Definitions for tx_flags in struct skb_shared_info */
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enum {
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/* generate hardware time stamp */
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SKBTX_HW_TSTAMP = 1 << 0,
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/* generate software time stamp when queueing packet to NIC */
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SKBTX_SW_TSTAMP = 1 << 1,
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/* device driver is going to provide hardware time stamp */
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SKBTX_IN_PROGRESS = 1 << 2,
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/* generate wifi status information (where possible) */
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SKBTX_WIFI_STATUS = 1 << 4,
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/* generate software time stamp when entering packet scheduling */
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SKBTX_SCHED_TSTAMP = 1 << 6,
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};
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#define SKBTX_ANY_SW_TSTAMP (SKBTX_SW_TSTAMP | \
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SKBTX_SCHED_TSTAMP)
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#define SKBTX_ANY_TSTAMP (SKBTX_HW_TSTAMP | SKBTX_ANY_SW_TSTAMP)
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/* Definitions for flags in struct skb_shared_info */
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enum {
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/* use zcopy routines */
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SKBFL_ZEROCOPY_ENABLE = BIT(0),
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|
|
/* 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
|
|
*/
|
|
SKBFL_SHARED_FRAG = BIT(1),
|
|
};
|
|
|
|
#define SKBFL_ZEROCOPY_FRAG (SKBFL_ZEROCOPY_ENABLE | SKBFL_SHARED_FRAG)
|
|
|
|
/*
|
|
* 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 sk_buff *, 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;
|
|
u8 flags;
|
|
|
|
struct mmpin {
|
|
struct user_struct *user;
|
|
unsigned int num_pg;
|
|
} mmp;
|
|
};
|
|
|
|
#define skb_uarg(SKB) ((struct ubuf_info *)(skb_shinfo(SKB)->destructor_arg))
|
|
|
|
int mm_account_pinned_pages(struct mmpin *mmp, size_t size);
|
|
void mm_unaccount_pinned_pages(struct mmpin *mmp);
|
|
|
|
struct ubuf_info *msg_zerocopy_alloc(struct sock *sk, size_t size);
|
|
struct ubuf_info *msg_zerocopy_realloc(struct sock *sk, size_t size,
|
|
struct ubuf_info *uarg);
|
|
|
|
void msg_zerocopy_put_abort(struct ubuf_info *uarg, bool have_uref);
|
|
|
|
void msg_zerocopy_callback(struct sk_buff *skb, struct ubuf_info *uarg,
|
|
bool success);
|
|
|
|
int skb_zerocopy_iter_dgram(struct sk_buff *skb, struct msghdr *msg, int len);
|
|
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 {
|
|
__u8 flags;
|
|
__u8 meta_len;
|
|
__u8 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;
|
|
|
|
/*
|
|
* 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,
|
|
|
|
SKB_GSO_UDP = 1 << 16,
|
|
|
|
SKB_GSO_UDP_L4 = 1 << 17,
|
|
|
|
SKB_GSO_FRAGLIST = 1 << 18,
|
|
};
|
|
|
|
#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
|
|
* @skb_mstamp_ns: (aka @tstamp) earliest departure time; start point
|
|
* for retransmit timer
|
|
* @rbnode: RB tree node, alternative to next/prev for netem/tcp
|
|
* @list: queue head
|
|
* @sk: Socket we are owned by
|
|
* @ip_defrag_offset: (aka @sk) alternate use of @sk, used in
|
|
* fragmentation management
|
|
* @dev: Device we arrived on/are leaving by
|
|
* @dev_scratch: (aka @dev) alternate use of @dev when @dev would be %NULL
|
|
* @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
|
|
* @inner_protocol_type: whether the inner protocol is
|
|
* ENCAP_TYPE_ETHER or ENCAP_TYPE_IPPROTO
|
|
* @remcsum_offload: remote checksum offload is enabled
|
|
* @offload_fwd_mark: Packet was L2-forwarded in hardware
|
|
* @offload_l3_fwd_mark: Packet was L3-forwarded in hardware
|
|
* @tc_skip_classify: do not classify packet. set by IFB device
|
|
* @tc_at_ingress: used within tc_classify to distinguish in/egress
|
|
* @redirected: packet was redirected by packet classifier
|
|
* @from_ingress: packet was redirected from the ingress path
|
|
* @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
|
|
* @tcp_tsorted_anchor: list structure for TCP (tp->tsorted_sent_queue)
|
|
* @_sk_redir: socket redirection information for skmsg
|
|
* @_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
|
|
* @head_frag: skb was allocated from page fragments,
|
|
* not allocated by kmalloc() or vmalloc().
|
|
* @pfmemalloc: skbuff was allocated from PFMEMALLOC reserves
|
|
* @active_extensions: active extensions (skb_ext_id types)
|
|
* @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
|
|
* @encapsulation: indicates the inner headers in the skbuff are valid
|
|
* @encap_hdr_csum: software checksum is needed
|
|
* @csum_valid: checksum is already valid
|
|
* @csum_not_inet: use CRC32c to resolve CHECKSUM_PARTIAL
|
|
* @csum_complete_sw: checksum was completed by software
|
|
* @csum_level: indicates the number of consecutive checksums found in
|
|
* the packet minus one that have been verified as
|
|
* CHECKSUM_UNNECESSARY (max 3)
|
|
* @dst_pending_confirm: need to confirm neighbour
|
|
* @decrypted: Decrypted SKB
|
|
* @napi_id: id of the NAPI struct this skb came from
|
|
* @sender_cpu: (aka @napi_id) source CPU in XPS
|
|
* @secmark: security marking
|
|
* @mark: Generic packet mark
|
|
* @reserved_tailroom: (aka @mark) number of bytes of free space available
|
|
* at the tail of an sk_buff
|
|
* @vlan_present: VLAN tag is present
|
|
* @vlan_proto: vlan encapsulation protocol
|
|
* @vlan_tci: vlan tag control information
|
|
* @inner_protocol: Protocol (encapsulation)
|
|
* @inner_ipproto: (aka @inner_protocol) stores ipproto when
|
|
* skb->inner_protocol_type == ENCAP_TYPE_IPPROTO;
|
|
* @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
|
|
* @kcov_handle: KCOV remote handle for remote coverage collection
|
|
* @tail: Tail pointer
|
|
* @end: End pointer
|
|
* @head: Head of buffer
|
|
* @data: Data head pointer
|
|
* @truesize: Buffer size
|
|
* @users: User count - see {datagram,tcp}.c
|
|
* @extensions: allocated extensions, valid if active_extensions is nonzero
|
|
*/
|
|
|
|
struct sk_buff {
|
|
union {
|
|
struct {
|
|
/* These two members must be first. */
|
|
struct sk_buff *next;
|
|
struct sk_buff *prev;
|
|
|
|
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;
|
|
};
|
|
};
|
|
struct rb_node rbnode; /* used in netem, ip4 defrag, and tcp stack */
|
|
struct list_head list;
|
|
};
|
|
|
|
union {
|
|
struct sock *sk;
|
|
int ip_defrag_offset;
|
|
};
|
|
|
|
union {
|
|
ktime_t tstamp;
|
|
u64 skb_mstamp_ns; /* earliest departure time */
|
|
};
|
|
/*
|
|
* 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);
|
|
|
|
union {
|
|
struct {
|
|
unsigned long _skb_refdst;
|
|
void (*destructor)(struct sk_buff *skb);
|
|
};
|
|
struct list_head tcp_tsorted_anchor;
|
|
#ifdef CONFIG_NET_SOCK_MSG
|
|
unsigned long _sk_redir;
|
|
#endif
|
|
};
|
|
|
|
#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
|
|
unsigned long _nfct;
|
|
#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.
|
|
*/
|
|
__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)
|
|
|
|
/* private: */
|
|
__u8 __cloned_offset[0];
|
|
/* public: */
|
|
__u8 cloned:1,
|
|
nohdr:1,
|
|
fclone:2,
|
|
peeked:1,
|
|
head_frag:1,
|
|
pfmemalloc:1;
|
|
#ifdef CONFIG_SKB_EXTENSIONS
|
|
__u8 active_extensions;
|
|
#endif
|
|
/* 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)
|
|
|
|
/* private: */
|
|
__u8 __pkt_type_offset[0];
|
|
/* public: */
|
|
__u8 pkt_type:3;
|
|
__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;
|
|
|
|
#ifdef __BIG_ENDIAN_BITFIELD
|
|
#define PKT_VLAN_PRESENT_BIT 7
|
|
#else
|
|
#define PKT_VLAN_PRESENT_BIT 0
|
|
#endif
|
|
#define PKT_VLAN_PRESENT_OFFSET() offsetof(struct sk_buff, __pkt_vlan_present_offset)
|
|
/* private: */
|
|
__u8 __pkt_vlan_present_offset[0];
|
|
/* public: */
|
|
__u8 vlan_present: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;
|
|
__u8 offload_l3_fwd_mark:1;
|
|
#endif
|
|
#ifdef CONFIG_NET_CLS_ACT
|
|
__u8 tc_skip_classify:1;
|
|
__u8 tc_at_ingress:1;
|
|
#endif
|
|
#ifdef CONFIG_NET_REDIRECT
|
|
__u8 redirected:1;
|
|
__u8 from_ingress:1;
|
|
#endif
|
|
#ifdef CONFIG_TLS_DEVICE
|
|
__u8 decrypted: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;
|
|
|
|
#ifdef CONFIG_KCOV
|
|
u64 kcov_handle;
|
|
#endif
|
|
|
|
/* 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 CONFIG_SKB_EXTENSIONS
|
|
/* only useable after checking ->active_extensions != 0 */
|
|
struct skb_ext *extensions;
|
|
#endif
|
|
};
|
|
|
|
#ifdef __KERNEL__
|
|
/*
|
|
* Handling routines are only of interest to the kernel
|
|
*/
|
|
|
|
#define SKB_ALLOC_FCLONE 0x01
|
|
#define SKB_ALLOC_RX 0x02
|
|
#define SKB_ALLOC_NAPI 0x04
|
|
|
|
/**
|
|
* skb_pfmemalloc - Test if the skb was allocated from PFMEMALLOC reserves
|
|
* @skb: buffer
|
|
*/
|
|
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)
|
|
|
|
/**
|
|
* 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);
|
|
}
|
|
|
|
/**
|
|
* skb_rtable - Returns the skb &rtable
|
|
* @skb: buffer
|
|
*/
|
|
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;
|
|
}
|
|
|
|
/**
|
|
* skb_napi_id - Returns the skb's NAPI id
|
|
* @skb: buffer
|
|
*/
|
|
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
|
|
}
|
|
|
|
/**
|
|
* skb_unref - decrement the skb's reference count
|
|
* @skb: buffer
|
|
*
|
|
* Returns 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_dump(const char *level, const struct sk_buff *skb, bool full_pkt);
|
|
void skb_tx_error(struct sk_buff *skb);
|
|
|
|
#ifdef CONFIG_TRACEPOINTS
|
|
void consume_skb(struct sk_buff *skb);
|
|
#else
|
|
static inline void consume_skb(struct sk_buff *skb)
|
|
{
|
|
return kfree_skb(skb);
|
|
}
|
|
#endif
|
|
|
|
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);
|
|
struct sk_buff *build_skb_around(struct sk_buff *skb,
|
|
void *data, unsigned int frag_size);
|
|
|
|
struct sk_buff *napi_build_skb(void *data, unsigned int frag_size);
|
|
|
|
/**
|
|
* alloc_skb - allocate a network buffer
|
|
* @size: size to allocate
|
|
* @priority: allocation mask
|
|
*
|
|
* This function is a convenient wrapper around __alloc_skb().
|
|
*/
|
|
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);
|
|
struct sk_buff *alloc_skb_for_msg(struct sk_buff *first);
|
|
|
|
/* 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 &&
|
|
READ_ONCE(fclones->skb2.sk) == sk;
|
|
}
|
|
|
|
/**
|
|
* alloc_skb_fclone - allocate a network buffer from fclone cache
|
|
* @size: size to allocate
|
|
* @priority: allocation mask
|
|
*
|
|
* This function is a convenient wrapper around __alloc_skb().
|
|
*/
|
|
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);
|
|
void skb_headers_offset_update(struct sk_buff *skb, int off);
|
|
int skb_copy_ubufs(struct sk_buff *skb, gfp_t gfp_mask);
|
|
struct sk_buff *skb_clone(struct sk_buff *skb, gfp_t priority);
|
|
void skb_copy_header(struct sk_buff *new, const struct sk_buff *old);
|
|
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_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;
|
|
__u32 frag_off;
|
|
};
|
|
|
|
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, const void *data,
|
|
const struct flow_keys_basic *keys, int hlen);
|
|
__be32 __skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto,
|
|
const 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);
|
|
|
|
struct bpf_flow_dissector;
|
|
bool bpf_flow_dissect(struct bpf_prog *prog, struct bpf_flow_dissector *ctx,
|
|
__be16 proto, int nhoff, int hlen, unsigned int flags);
|
|
|
|
bool __skb_flow_dissect(const struct net *net,
|
|
const struct sk_buff *skb,
|
|
struct flow_dissector *flow_dissector,
|
|
void *target_container, const 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(NULL, 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(NULL, skb, &flow_keys_dissector,
|
|
flow, NULL, 0, 0, 0, flags);
|
|
}
|
|
|
|
static inline bool
|
|
skb_flow_dissect_flow_keys_basic(const struct net *net,
|
|
const struct sk_buff *skb,
|
|
struct flow_keys_basic *flow,
|
|
const void *data, __be16 proto,
|
|
int nhoff, int hlen, unsigned int flags)
|
|
{
|
|
memset(flow, 0, sizeof(*flow));
|
|
return __skb_flow_dissect(net, skb, &flow_keys_basic_dissector, flow,
|
|
data, proto, nhoff, hlen, flags);
|
|
}
|
|
|
|
void skb_flow_dissect_meta(const struct sk_buff *skb,
|
|
struct flow_dissector *flow_dissector,
|
|
void *target_container);
|
|
|
|
/* Gets a skb connection tracking info, ctinfo map should be a
|
|
* map of mapsize to translate enum ip_conntrack_info states
|
|
* to user states.
|
|
*/
|
|
void
|
|
skb_flow_dissect_ct(const struct sk_buff *skb,
|
|
struct flow_dissector *flow_dissector,
|
|
void *target_container,
|
|
u16 *ctinfo_map, size_t mapsize,
|
|
bool post_ct);
|
|
void
|
|
skb_flow_dissect_tunnel_info(const struct sk_buff *skb,
|
|
struct flow_dissector *flow_dissector,
|
|
void *target_container);
|
|
|
|
void skb_flow_dissect_hash(const struct sk_buff *skb,
|
|
struct flow_dissector *flow_dissector,
|
|
void *target_container);
|
|
|
|
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,
|
|
const siphash_key_t *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;
|
|
};
|
|
|
|
static inline void skb_copy_decrypted(struct sk_buff *to,
|
|
const struct sk_buff *from)
|
|
{
|
|
#ifdef CONFIG_TLS_DEVICE
|
|
to->decrypted = from->decrypted;
|
|
#endif
|
|
}
|
|
|
|
#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)->flags & SKBFL_ZEROCOPY_ENABLE;
|
|
|
|
return is_zcopy ? skb_uarg(skb) : NULL;
|
|
}
|
|
|
|
static inline void net_zcopy_get(struct ubuf_info *uarg)
|
|
{
|
|
refcount_inc(&uarg->refcnt);
|
|
}
|
|
|
|
static inline void skb_zcopy_init(struct sk_buff *skb, struct ubuf_info *uarg)
|
|
{
|
|
skb_shinfo(skb)->destructor_arg = uarg;
|
|
skb_shinfo(skb)->flags |= uarg->flags;
|
|
}
|
|
|
|
static inline void skb_zcopy_set(struct sk_buff *skb, struct ubuf_info *uarg,
|
|
bool *have_ref)
|
|
{
|
|
if (skb && uarg && !skb_zcopy(skb)) {
|
|
if (unlikely(have_ref && *have_ref))
|
|
*have_ref = false;
|
|
else
|
|
net_zcopy_get(uarg);
|
|
skb_zcopy_init(skb, uarg);
|
|
}
|
|
}
|
|
|
|
static inline void skb_zcopy_set_nouarg(struct sk_buff *skb, void *val)
|
|
{
|
|
skb_shinfo(skb)->destructor_arg = (void *)((uintptr_t) val | 0x1UL);
|
|
skb_shinfo(skb)->flags |= SKBFL_ZEROCOPY_FRAG;
|
|
}
|
|
|
|
static inline bool skb_zcopy_is_nouarg(struct sk_buff *skb)
|
|
{
|
|
return (uintptr_t) skb_shinfo(skb)->destructor_arg & 0x1UL;
|
|
}
|
|
|
|
static inline void *skb_zcopy_get_nouarg(struct sk_buff *skb)
|
|
{
|
|
return (void *)((uintptr_t) skb_shinfo(skb)->destructor_arg & ~0x1UL);
|
|
}
|
|
|
|
static inline void net_zcopy_put(struct ubuf_info *uarg)
|
|
{
|
|
if (uarg)
|
|
uarg->callback(NULL, uarg, true);
|
|
}
|
|
|
|
static inline void net_zcopy_put_abort(struct ubuf_info *uarg, bool have_uref)
|
|
{
|
|
if (uarg) {
|
|
if (uarg->callback == msg_zerocopy_callback)
|
|
msg_zerocopy_put_abort(uarg, have_uref);
|
|
else if (have_uref)
|
|
net_zcopy_put(uarg);
|
|
}
|
|
}
|
|
|
|
/* Release a reference on a zerocopy structure */
|
|
static inline void skb_zcopy_clear(struct sk_buff *skb, bool zerocopy_success)
|
|
{
|
|
struct ubuf_info *uarg = skb_zcopy(skb);
|
|
|
|
if (uarg) {
|
|
if (!skb_zcopy_is_nouarg(skb))
|
|
uarg->callback(skb, uarg, zerocopy_success);
|
|
|
|
skb_shinfo(skb)->flags &= ~SKBFL_ZEROCOPY_FRAG;
|
|
}
|
|
}
|
|
|
|
static inline void skb_mark_not_on_list(struct sk_buff *skb)
|
|
{
|
|
skb->next = NULL;
|
|
}
|
|
|
|
/* Iterate through singly-linked GSO fragments of an skb. */
|
|
#define skb_list_walk_safe(first, skb, next_skb) \
|
|
for ((skb) = (first), (next_skb) = (skb) ? (skb)->next : NULL; (skb); \
|
|
(skb) = (next_skb), (next_skb) = (skb) ? (skb)->next : NULL)
|
|
|
|
static inline void skb_list_del_init(struct sk_buff *skb)
|
|
{
|
|
__list_del_entry(&skb->list);
|
|
skb_mark_not_on_list(skb);
|
|
}
|
|
|
|
/**
|
|
* 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_empty_lockless - check if a queue is empty
|
|
* @list: queue head
|
|
*
|
|
* Returns true if the queue is empty, false otherwise.
|
|
* This variant can be used in lockless contexts.
|
|
*/
|
|
static inline bool skb_queue_empty_lockless(const struct sk_buff_head *list)
|
|
{
|
|
return READ_ONCE(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 can avoid redundant atomic changes.
|
|
*/
|
|
|
|
/**
|
|
* 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
|
|
*/
|
|
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 - peek at the head of a non-empty &sk_buff_head
|
|
* @list_: list to peek at
|
|
*
|
|
* Like skb_peek(), but the caller knows that the list is not empty.
|
|
*/
|
|
static inline struct sk_buff *__skb_peek(const struct sk_buff_head *list_)
|
|
{
|
|
return list_->next;
|
|
}
|
|
|
|
/**
|
|
* 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 = READ_ONCE(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_len_lockless - get queue length
|
|
* @list_: list to measure
|
|
*
|
|
* Return the length of an &sk_buff queue.
|
|
* This variant can be used in lockless contexts.
|
|
*/
|
|
static inline __u32 skb_queue_len_lockless(const struct sk_buff_head *list_)
|
|
{
|
|
return READ_ONCE(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.
|
|
*/
|
|
static inline void __skb_insert(struct sk_buff *newsk,
|
|
struct sk_buff *prev, struct sk_buff *next,
|
|
struct sk_buff_head *list)
|
|
{
|
|
/* See skb_queue_empty_lockless() and skb_peek_tail()
|
|
* for the opposite READ_ONCE()
|
|
*/
|
|
WRITE_ONCE(newsk->next, next);
|
|
WRITE_ONCE(newsk->prev, prev);
|
|
WRITE_ONCE(next->prev, newsk);
|
|
WRITE_ONCE(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;
|
|
|
|
WRITE_ONCE(first->prev, prev);
|
|
WRITE_ONCE(prev->next, first);
|
|
|
|
WRITE_ONCE(last->next, next);
|
|
WRITE_ONCE(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.
|
|
*/
|
|
static inline void __skb_queue_head(struct sk_buff_head *list,
|
|
struct sk_buff *newsk)
|
|
{
|
|
__skb_queue_after(list, (struct sk_buff *)list, newsk);
|
|
}
|
|
void skb_queue_head(struct sk_buff_head *list, struct sk_buff *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.
|
|
*/
|
|
static inline void __skb_queue_tail(struct sk_buff_head *list,
|
|
struct sk_buff *newsk)
|
|
{
|
|
__skb_queue_before(list, (struct sk_buff *)list, newsk);
|
|
}
|
|
void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *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;
|
|
|
|
WRITE_ONCE(list->qlen, list->qlen - 1);
|
|
next = skb->next;
|
|
prev = skb->prev;
|
|
skb->next = skb->prev = NULL;
|
|
WRITE_ONCE(next->prev, prev);
|
|
WRITE_ONCE(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.
|
|
*/
|
|
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;
|
|
}
|
|
struct sk_buff *skb_dequeue(struct sk_buff_head *list);
|
|
|
|
/**
|
|
* __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.
|
|
*/
|
|
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;
|
|
}
|
|
struct sk_buff *skb_dequeue_tail(struct sk_buff_head *list);
|
|
|
|
|
|
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->bv_page = page;
|
|
frag->bv_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_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 bool pskb_may_pull(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
if (likely(len <= skb_headlen(skb)))
|
|
return true;
|
|
if (unlikely(len > skb->len))
|
|
return false;
|
|
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_unset_mac_header(struct sk_buff *skb)
|
|
{
|
|
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)
|
|
{
|
|
struct flow_keys_basic keys;
|
|
|
|
if (skb_transport_header_was_set(skb))
|
|
return;
|
|
|
|
if (skb_flow_dissect_flow_keys_basic(NULL, skb, &keys,
|
|
NULL, 0, 0, 0, 0))
|
|
skb_set_transport_header(skb, keys.control.thoff);
|
|
}
|
|
|
|
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_cpu() 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 (WARN_ON(skb_is_nonlinear(skb)))
|
|
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_zcopy_is_nouarg(skb) &&
|
|
skb_uarg(skb)->callback == msg_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.
|
|
*/
|
|
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_queue_purge(struct sk_buff_head *list);
|
|
|
|
unsigned int skb_rbtree_purge(struct rb_root *root);
|
|
|
|
void *__netdev_alloc_frag_align(unsigned int fragsz, unsigned int align_mask);
|
|
|
|
/**
|
|
* netdev_alloc_frag - allocate a page fragment
|
|
* @fragsz: fragment size
|
|
*
|
|
* Allocates a frag from a page for receive buffer.
|
|
* Uses GFP_ATOMIC allocations.
|
|
*/
|
|
static inline void *netdev_alloc_frag(unsigned int fragsz)
|
|
{
|
|
return __netdev_alloc_frag_align(fragsz, ~0u);
|
|
}
|
|
|
|
static inline void *netdev_alloc_frag_align(unsigned int fragsz,
|
|
unsigned int align)
|
|
{
|
|
WARN_ON_ONCE(!is_power_of_2(align));
|
|
return __netdev_alloc_frag_align(fragsz, -align);
|
|
}
|
|
|
|
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_align(unsigned int fragsz, unsigned int align_mask);
|
|
|
|
static inline void *napi_alloc_frag(unsigned int fragsz)
|
|
{
|
|
return __napi_alloc_frag_align(fragsz, ~0u);
|
|
}
|
|
|
|
static inline void *napi_alloc_frag_align(unsigned int fragsz,
|
|
unsigned int align)
|
|
{
|
|
WARN_ON_ONCE(!is_power_of_2(align));
|
|
return __napi_alloc_frag_align(fragsz, -align);
|
|
}
|
|
|
|
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 napi_skb_free_stolen_head(struct sk_buff *skb);
|
|
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_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);
|
|
}
|
|
|
|
/**
|
|
* dev_page_is_reusable - check whether a page can be reused for network Rx
|
|
* @page: the page to test
|
|
*
|
|
* A page shouldn't be considered for reusing/recycling if it was allocated
|
|
* under memory pressure or at a distant memory node.
|
|
*
|
|
* Returns false if this page should be returned to page allocator, true
|
|
* otherwise.
|
|
*/
|
|
static inline bool dev_page_is_reusable(const struct page *page)
|
|
{
|
|
return likely(page_to_nid(page) == numa_mem_id() &&
|
|
!page_is_pfmemalloc(page));
|
|
}
|
|
|
|
/**
|
|
* 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(const struct page *page,
|
|
struct sk_buff *skb)
|
|
{
|
|
if (page_is_pfmemalloc(page))
|
|
skb->pfmemalloc = true;
|
|
}
|
|
|
|
/**
|
|
* skb_frag_off() - Returns the offset of a skb fragment
|
|
* @frag: the paged fragment
|
|
*/
|
|
static inline unsigned int skb_frag_off(const skb_frag_t *frag)
|
|
{
|
|
return frag->bv_offset;
|
|
}
|
|
|
|
/**
|
|
* skb_frag_off_add() - Increments the offset of a skb fragment by @delta
|
|
* @frag: skb fragment
|
|
* @delta: value to add
|
|
*/
|
|
static inline void skb_frag_off_add(skb_frag_t *frag, int delta)
|
|
{
|
|
frag->bv_offset += delta;
|
|
}
|
|
|
|
/**
|
|
* skb_frag_off_set() - Sets the offset of a skb fragment
|
|
* @frag: skb fragment
|
|
* @offset: offset of fragment
|
|
*/
|
|
static inline void skb_frag_off_set(skb_frag_t *frag, unsigned int offset)
|
|
{
|
|
frag->bv_offset = offset;
|
|
}
|
|
|
|
/**
|
|
* skb_frag_off_copy() - Sets the offset of a skb fragment from another fragment
|
|
* @fragto: skb fragment where offset is set
|
|
* @fragfrom: skb fragment offset is copied from
|
|
*/
|
|
static inline void skb_frag_off_copy(skb_frag_t *fragto,
|
|
const skb_frag_t *fragfrom)
|
|
{
|
|
fragto->bv_offset = fragfrom->bv_offset;
|
|
}
|
|
|
|
/**
|
|
* 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->bv_page;
|
|
}
|
|
|
|
/**
|
|
* __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)) + skb_frag_off(frag);
|
|
}
|
|
|
|
/**
|
|
* 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 + skb_frag_off(frag);
|
|
}
|
|
|
|
/**
|
|
* skb_frag_page_copy() - sets the page in a fragment from another fragment
|
|
* @fragto: skb fragment where page is set
|
|
* @fragfrom: skb fragment page is copied from
|
|
*/
|
|
static inline void skb_frag_page_copy(skb_frag_t *fragto,
|
|
const skb_frag_t *fragfrom)
|
|
{
|
|
fragto->bv_page = fragfrom->bv_page;
|
|
}
|
|
|
|
/**
|
|
* __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->bv_page = 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),
|
|
skb_frag_off(frag) + 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 __must_check __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 __must_check 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 skb_frag_t *frag = &skb_shinfo(skb)->frags[i - 1];
|
|
|
|
return page == skb_frag_page(frag) &&
|
|
off == skb_frag_off(frag) + 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)->flags & SKBFL_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;
|
|
}
|
|
|
|
int pskb_trim_rcsum_slow(struct sk_buff *skb, unsigned int len);
|
|
/**
|
|
* 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.
|
|
* It can change skb pointers.
|
|
*/
|
|
|
|
static inline int pskb_trim_rcsum(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
if (likely(len >= skb->len))
|
|
return 0;
|
|
return pskb_trim_rcsum_slow(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 rb_to_skb(rb) rb_entry_safe(rb, struct sk_buff, rbnode)
|
|
#define skb_rb_first(root) rb_to_skb(rb_first(root))
|
|
#define skb_rb_last(root) rb_to_skb(rb_last(root))
|
|
#define skb_rb_next(skb) rb_to_skb(rb_next(&(skb)->rbnode))
|
|
#define skb_rb_prev(skb) rb_to_skb(rb_prev(&(skb)->rbnode))
|
|
|
|
#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_rbtree_walk(skb, root) \
|
|
for (skb = skb_rb_first(root); skb != NULL; \
|
|
skb = skb_rb_next(skb))
|
|
|
|
#define skb_rbtree_walk_from(skb) \
|
|
for (; skb != NULL; \
|
|
skb = skb_rb_next(skb))
|
|
|
|
#define skb_rbtree_walk_from_safe(skb, tmp) \
|
|
for (; tmp = skb ? skb_rb_next(skb) : NULL, (skb != NULL); \
|
|
skb = tmp)
|
|
|
|
#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, struct sk_buff_head *queue,
|
|
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,
|
|
int *off, int *err,
|
|
struct sk_buff **last);
|
|
struct sk_buff *__skb_try_recv_datagram(struct sock *sk,
|
|
struct sk_buff_head *queue,
|
|
unsigned int flags, int *off, int *err,
|
|
struct sk_buff **last);
|
|
struct sk_buff *__skb_recv_datagram(struct sock *sk,
|
|
struct sk_buff_head *sk_queue,
|
|
unsigned int flags, int *off, int *err);
|
|
struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags, int noblock,
|
|
int *err);
|
|
__poll_t 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_and_hash_datagram_iter(const struct sk_buff *skb, int offset,
|
|
struct iov_iter *to, int len,
|
|
struct ahash_request *hash);
|
|
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);
|
|
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);
|
|
bool skb_gso_validate_network_len(const struct sk_buff *skb, unsigned int mtu);
|
|
bool skb_gso_validate_mac_len(const struct sk_buff *skb, unsigned int len);
|
|
struct sk_buff *skb_segment(struct sk_buff *skb, netdev_features_t features);
|
|
struct sk_buff *skb_segment_list(struct sk_buff *skb, netdev_features_t features,
|
|
unsigned int offset);
|
|
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);
|
|
int skb_eth_pop(struct sk_buff *skb);
|
|
int skb_eth_push(struct sk_buff *skb, const unsigned char *dst,
|
|
const unsigned char *src);
|
|
int skb_mpls_push(struct sk_buff *skb, __be32 mpls_lse, __be16 mpls_proto,
|
|
int mac_len, bool ethernet);
|
|
int skb_mpls_pop(struct sk_buff *skb, __be16 next_proto, int mac_len,
|
|
bool ethernet);
|
|
int skb_mpls_update_lse(struct sk_buff *skb, __be32 mpls_lse);
|
|
int skb_mpls_dec_ttl(struct sk_buff *skb);
|
|
struct sk_buff *pskb_extract(struct sk_buff *skb, int off, int to_copy,
|
|
gfp_t gfp);
|
|
|
|
static inline int memcpy_from_msg(void *data, struct msghdr *msg, int len)
|
|
{
|
|
return copy_from_iter_full(data, len, &msg->msg_iter) ? 0 : -EFAULT;
|
|
}
|
|
|
|
static inline int memcpy_to_msg(struct msghdr *msg, void *data, int len)
|
|
{
|
|
return copy_to_iter(data, len, &msg->msg_iter) == len ? 0 : -EFAULT;
|
|
}
|
|
|
|
struct skb_checksum_ops {
|
|
__wsum (*update)(const void *mem, int len, __wsum wsum);
|
|
__wsum (*combine)(__wsum csum, __wsum csum2, int offset, int len);
|
|
};
|
|
|
|
extern const struct skb_checksum_ops *crc32c_csum_stub __read_mostly;
|
|
|
|
__wsum __skb_checksum(const struct sk_buff *skb, int offset, int len,
|
|
__wsum csum, const struct skb_checksum_ops *ops);
|
|
__wsum skb_checksum(const struct sk_buff *skb, int offset, int len,
|
|
__wsum csum);
|
|
|
|
static inline void * __must_check
|
|
__skb_header_pointer(const struct sk_buff *skb, int offset, int len,
|
|
const void *data, int hlen, void *buffer)
|
|
{
|
|
if (likely(hlen - offset >= len))
|
|
return (void *)data + offset;
|
|
|
|
if (!skb || unlikely(skb_copy_bits(skb, offset, buffer, len) < 0))
|
|
return NULL;
|
|
|
|
return buffer;
|
|
}
|
|
|
|
static inline void * __must_check
|
|
skb_header_pointer(const struct sk_buff *skb, int offset, int len, void *buffer)
|
|
{
|
|
return __skb_header_pointer(skb, offset, len, skb->data,
|
|
skb_headlen(skb), buffer);
|
|
}
|
|
|
|
/**
|
|
* skb_needs_linearize - check if we need to linearize a given skb
|
|
* depending on the given device features.
|
|
* @skb: socket buffer to check
|
|
* @features: net device features
|
|
*
|
|
* Returns true if either:
|
|
* 1. skb has frag_list and the device doesn't support FRAGLIST, or
|
|
* 2. skb is fragmented and the device does not support SG.
|
|
*/
|
|
static inline bool skb_needs_linearize(struct sk_buff *skb,
|
|
netdev_features_t features)
|
|
{
|
|
return skb_is_nonlinear(skb) &&
|
|
((skb_has_frag_list(skb) && !(features & NETIF_F_FRAGLIST)) ||
|
|
(skb_shinfo(skb)->nr_frags && !(features & NETIF_F_SG)));
|
|
}
|
|
|
|
static inline void skb_copy_from_linear_data(const struct sk_buff *skb,
|
|
void *to,
|
|
const unsigned int len)
|
|
{
|
|
memcpy(to, skb->data, len);
|
|
}
|
|
|
|
static inline void skb_copy_from_linear_data_offset(const struct sk_buff *skb,
|
|
const int offset, void *to,
|
|
const unsigned int len)
|
|
{
|
|
memcpy(to, skb->data + offset, len);
|
|
}
|
|
|
|
static inline void skb_copy_to_linear_data(struct sk_buff *skb,
|
|
const void *from,
|
|
const unsigned int len)
|
|
{
|
|
memcpy(skb->data, from, len);
|
|
}
|
|
|
|
static inline void skb_copy_to_linear_data_offset(struct sk_buff *skb,
|
|
const int offset,
|
|
const void *from,
|
|
const unsigned int len)
|
|
{
|
|
memcpy(skb->data + offset, from, len);
|
|
}
|
|
|
|
void skb_init(void);
|
|
|
|
static inline ktime_t skb_get_ktime(const struct sk_buff *skb)
|
|
{
|
|
return skb->tstamp;
|
|
}
|
|
|
|
/**
|
|
* skb_get_timestamp - get timestamp from a skb
|
|
* @skb: skb to get stamp from
|
|
* @stamp: pointer to struct __kernel_old_timeval to store stamp in
|
|
*
|
|
* Timestamps are stored in the skb as offsets to a base timestamp.
|
|
* This function converts the offset back to a struct timeval and stores
|
|
* it in stamp.
|
|
*/
|
|
static inline void skb_get_timestamp(const struct sk_buff *skb,
|
|
struct __kernel_old_timeval *stamp)
|
|
{
|
|
*stamp = ns_to_kernel_old_timeval(skb->tstamp);
|
|
}
|
|
|
|
static inline void skb_get_new_timestamp(const struct sk_buff *skb,
|
|
struct __kernel_sock_timeval *stamp)
|
|
{
|
|
struct timespec64 ts = ktime_to_timespec64(skb->tstamp);
|
|
|
|
stamp->tv_sec = ts.tv_sec;
|
|
stamp->tv_usec = ts.tv_nsec / 1000;
|
|
}
|
|
|
|
static inline void skb_get_timestampns(const struct sk_buff *skb,
|
|
struct __kernel_old_timespec *stamp)
|
|
{
|
|
struct timespec64 ts = ktime_to_timespec64(skb->tstamp);
|
|
|
|
stamp->tv_sec = ts.tv_sec;
|
|
stamp->tv_nsec = ts.tv_nsec;
|
|
}
|
|
|
|
static inline void skb_get_new_timestampns(const struct sk_buff *skb,
|
|
struct __kernel_timespec *stamp)
|
|
{
|
|
struct timespec64 ts = ktime_to_timespec64(skb->tstamp);
|
|
|
|
stamp->tv_sec = ts.tv_sec;
|
|
stamp->tv_nsec = ts.tv_nsec;
|
|
}
|
|
|
|
static inline void __net_timestamp(struct sk_buff *skb)
|
|
{
|
|
skb->tstamp = ktime_get_real();
|
|
}
|
|
|
|
static inline ktime_t net_timedelta(ktime_t t)
|
|
{
|
|
return ktime_sub(ktime_get_real(), t);
|
|
}
|
|
|
|
static inline ktime_t net_invalid_timestamp(void)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline u8 skb_metadata_len(const struct sk_buff *skb)
|
|
{
|
|
return skb_shinfo(skb)->meta_len;
|
|
}
|
|
|
|
static inline void *skb_metadata_end(const struct sk_buff *skb)
|
|
{
|
|
return skb_mac_header(skb);
|
|
}
|
|
|
|
static inline bool __skb_metadata_differs(const struct sk_buff *skb_a,
|
|
const struct sk_buff *skb_b,
|
|
u8 meta_len)
|
|
{
|
|
const void *a = skb_metadata_end(skb_a);
|
|
const void *b = skb_metadata_end(skb_b);
|
|
/* Using more efficient varaiant than plain call to memcmp(). */
|
|
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
|
|
u64 diffs = 0;
|
|
|
|
switch (meta_len) {
|
|
#define __it(x, op) (x -= sizeof(u##op))
|
|
#define __it_diff(a, b, op) (*(u##op *)__it(a, op)) ^ (*(u##op *)__it(b, op))
|
|
case 32: diffs |= __it_diff(a, b, 64);
|
|
fallthrough;
|
|
case 24: diffs |= __it_diff(a, b, 64);
|
|
fallthrough;
|
|
case 16: diffs |= __it_diff(a, b, 64);
|
|
fallthrough;
|
|
case 8: diffs |= __it_diff(a, b, 64);
|
|
break;
|
|
case 28: diffs |= __it_diff(a, b, 64);
|
|
fallthrough;
|
|
case 20: diffs |= __it_diff(a, b, 64);
|
|
fallthrough;
|
|
case 12: diffs |= __it_diff(a, b, 64);
|
|
fallthrough;
|
|
case 4: diffs |= __it_diff(a, b, 32);
|
|
break;
|
|
}
|
|
return diffs;
|
|
#else
|
|
return memcmp(a - meta_len, b - meta_len, meta_len);
|
|
#endif
|
|
}
|
|
|
|
static inline bool skb_metadata_differs(const struct sk_buff *skb_a,
|
|
const struct sk_buff *skb_b)
|
|
{
|
|
u8 len_a = skb_metadata_len(skb_a);
|
|
u8 len_b = skb_metadata_len(skb_b);
|
|
|
|
if (!(len_a | len_b))
|
|
return false;
|
|
|
|
return len_a != len_b ?
|
|
true : __skb_metadata_differs(skb_a, skb_b, len_a);
|
|
}
|
|
|
|
static inline void skb_metadata_set(struct sk_buff *skb, u8 meta_len)
|
|
{
|
|
skb_shinfo(skb)->meta_len = meta_len;
|
|
}
|
|
|
|
static inline void skb_metadata_clear(struct sk_buff *skb)
|
|
{
|
|
skb_metadata_set(skb, 0);
|
|
}
|
|
|
|
struct sk_buff *skb_clone_sk(struct sk_buff *skb);
|
|
|
|
#ifdef CONFIG_NETWORK_PHY_TIMESTAMPING
|
|
|
|
void skb_clone_tx_timestamp(struct sk_buff *skb);
|
|
bool skb_defer_rx_timestamp(struct sk_buff *skb);
|
|
|
|
#else /* CONFIG_NETWORK_PHY_TIMESTAMPING */
|
|
|
|
static inline void skb_clone_tx_timestamp(struct sk_buff *skb)
|
|
{
|
|
}
|
|
|
|
static inline bool skb_defer_rx_timestamp(struct sk_buff *skb)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
#endif /* !CONFIG_NETWORK_PHY_TIMESTAMPING */
|
|
|
|
/**
|
|
* skb_complete_tx_timestamp() - deliver cloned skb with tx timestamps
|
|
*
|
|
* PHY drivers may accept clones of transmitted packets for
|
|
* timestamping via their phy_driver.txtstamp method. These drivers
|
|
* must call this function to return the skb back to the stack with a
|
|
* timestamp.
|
|
*
|
|
* @skb: clone of the original outgoing packet
|
|
* @hwtstamps: hardware time stamps
|
|
*
|
|
*/
|
|
void skb_complete_tx_timestamp(struct sk_buff *skb,
|
|
struct skb_shared_hwtstamps *hwtstamps);
|
|
|
|
void __skb_tstamp_tx(struct sk_buff *orig_skb, const struct sk_buff *ack_skb,
|
|
struct skb_shared_hwtstamps *hwtstamps,
|
|
struct sock *sk, int tstype);
|
|
|
|
/**
|
|
* skb_tstamp_tx - queue clone of skb with send time stamps
|
|
* @orig_skb: the original outgoing packet
|
|
* @hwtstamps: hardware time stamps, may be NULL if not available
|
|
*
|
|
* If the skb has a socket associated, then this function clones the
|
|
* skb (thus sharing the actual data and optional structures), stores
|
|
* the optional hardware time stamping information (if non NULL) or
|
|
* generates a software time stamp (otherwise), then queues the clone
|
|
* to the error queue of the socket. Errors are silently ignored.
|
|
*/
|
|
void skb_tstamp_tx(struct sk_buff *orig_skb,
|
|
struct skb_shared_hwtstamps *hwtstamps);
|
|
|
|
/**
|
|
* skb_tx_timestamp() - Driver hook for transmit timestamping
|
|
*
|
|
* Ethernet MAC Drivers should call this function in their hard_xmit()
|
|
* function immediately before giving the sk_buff to the MAC hardware.
|
|
*
|
|
* Specifically, one should make absolutely sure that this function is
|
|
* called before TX completion of this packet can trigger. Otherwise
|
|
* the packet could potentially already be freed.
|
|
*
|
|
* @skb: A socket buffer.
|
|
*/
|
|
static inline void skb_tx_timestamp(struct sk_buff *skb)
|
|
{
|
|
skb_clone_tx_timestamp(skb);
|
|
if (skb_shinfo(skb)->tx_flags & SKBTX_SW_TSTAMP)
|
|
skb_tstamp_tx(skb, NULL);
|
|
}
|
|
|
|
/**
|
|
* skb_complete_wifi_ack - deliver skb with wifi status
|
|
*
|
|
* @skb: the original outgoing packet
|
|
* @acked: ack status
|
|
*
|
|
*/
|
|
void skb_complete_wifi_ack(struct sk_buff *skb, bool acked);
|
|
|
|
__sum16 __skb_checksum_complete_head(struct sk_buff *skb, int len);
|
|
__sum16 __skb_checksum_complete(struct sk_buff *skb);
|
|
|
|
static inline int skb_csum_unnecessary(const struct sk_buff *skb)
|
|
{
|
|
return ((skb->ip_summed == CHECKSUM_UNNECESSARY) ||
|
|
skb->csum_valid ||
|
|
(skb->ip_summed == CHECKSUM_PARTIAL &&
|
|
skb_checksum_start_offset(skb) >= 0));
|
|
}
|
|
|
|
/**
|
|
* skb_checksum_complete - Calculate checksum of an entire packet
|
|
* @skb: packet to process
|
|
*
|
|
* This function calculates the checksum over the entire packet plus
|
|
* the value of skb->csum. The latter can be used to supply the
|
|
* checksum of a pseudo header as used by TCP/UDP. It returns the
|
|
* checksum.
|
|
*
|
|
* For protocols that contain complete checksums such as ICMP/TCP/UDP,
|
|
* this function can be used to verify that checksum on received
|
|
* packets. In that case the function should return zero if the
|
|
* checksum is correct. In particular, this function will return zero
|
|
* if skb->ip_summed is CHECKSUM_UNNECESSARY which indicates that the
|
|
* hardware has already verified the correctness of the checksum.
|
|
*/
|
|
static inline __sum16 skb_checksum_complete(struct sk_buff *skb)
|
|
{
|
|
return skb_csum_unnecessary(skb) ?
|
|
0 : __skb_checksum_complete(skb);
|
|
}
|
|
|
|
static inline void __skb_decr_checksum_unnecessary(struct sk_buff *skb)
|
|
{
|
|
if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
|
|
if (skb->csum_level == 0)
|
|
skb->ip_summed = CHECKSUM_NONE;
|
|
else
|
|
skb->csum_level--;
|
|
}
|
|
}
|
|
|
|
static inline void __skb_incr_checksum_unnecessary(struct sk_buff *skb)
|
|
{
|
|
if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
|
|
if (skb->csum_level < SKB_MAX_CSUM_LEVEL)
|
|
skb->csum_level++;
|
|
} else if (skb->ip_summed == CHECKSUM_NONE) {
|
|
skb->ip_summed = CHECKSUM_UNNECESSARY;
|
|
skb->csum_level = 0;
|
|
}
|
|
}
|
|
|
|
static inline void __skb_reset_checksum_unnecessary(struct sk_buff *skb)
|
|
{
|
|
if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
|
|
skb->ip_summed = CHECKSUM_NONE;
|
|
skb->csum_level = 0;
|
|
}
|
|
}
|
|
|
|
/* Check if we need to perform checksum complete validation.
|
|
*
|
|
* Returns true if checksum complete is needed, false otherwise
|
|
* (either checksum is unnecessary or zero checksum is allowed).
|
|
*/
|
|
static inline bool __skb_checksum_validate_needed(struct sk_buff *skb,
|
|
bool zero_okay,
|
|
__sum16 check)
|
|
{
|
|
if (skb_csum_unnecessary(skb) || (zero_okay && !check)) {
|
|
skb->csum_valid = 1;
|
|
__skb_decr_checksum_unnecessary(skb);
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
/* For small packets <= CHECKSUM_BREAK perform checksum complete directly
|
|
* in checksum_init.
|
|
*/
|
|
#define CHECKSUM_BREAK 76
|
|
|
|
/* Unset checksum-complete
|
|
*
|
|
* Unset checksum complete can be done when packet is being modified
|
|
* (uncompressed for instance) and checksum-complete value is
|
|
* invalidated.
|
|
*/
|
|
static inline void skb_checksum_complete_unset(struct sk_buff *skb)
|
|
{
|
|
if (skb->ip_summed == CHECKSUM_COMPLETE)
|
|
skb->ip_summed = CHECKSUM_NONE;
|
|
}
|
|
|
|
/* Validate (init) checksum based on checksum complete.
|
|
*
|
|
* Return values:
|
|
* 0: checksum is validated or try to in skb_checksum_complete. In the latter
|
|
* case the ip_summed will not be CHECKSUM_UNNECESSARY and the pseudo
|
|
* checksum is stored in skb->csum for use in __skb_checksum_complete
|
|
* non-zero: value of invalid checksum
|
|
*
|
|
*/
|
|
static inline __sum16 __skb_checksum_validate_complete(struct sk_buff *skb,
|
|
bool complete,
|
|
__wsum psum)
|
|
{
|
|
if (skb->ip_summed == CHECKSUM_COMPLETE) {
|
|
if (!csum_fold(csum_add(psum, skb->csum))) {
|
|
skb->csum_valid = 1;
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
skb->csum = psum;
|
|
|
|
if (complete || skb->len <= CHECKSUM_BREAK) {
|
|
__sum16 csum;
|
|
|
|
csum = __skb_checksum_complete(skb);
|
|
skb->csum_valid = !csum;
|
|
return csum;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static inline __wsum null_compute_pseudo(struct sk_buff *skb, int proto)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
/* Perform checksum validate (init). Note that this is a macro since we only
|
|
* want to calculate the pseudo header which is an input function if necessary.
|
|
* First we try to validate without any computation (checksum unnecessary) and
|
|
* then calculate based on checksum complete calling the function to compute
|
|
* pseudo header.
|
|
*
|
|
* Return values:
|
|
* 0: checksum is validated or try to in skb_checksum_complete
|
|
* non-zero: value of invalid checksum
|
|
*/
|
|
#define __skb_checksum_validate(skb, proto, complete, \
|
|
zero_okay, check, compute_pseudo) \
|
|
({ \
|
|
__sum16 __ret = 0; \
|
|
skb->csum_valid = 0; \
|
|
if (__skb_checksum_validate_needed(skb, zero_okay, check)) \
|
|
__ret = __skb_checksum_validate_complete(skb, \
|
|
complete, compute_pseudo(skb, proto)); \
|
|
__ret; \
|
|
})
|
|
|
|
#define skb_checksum_init(skb, proto, compute_pseudo) \
|
|
__skb_checksum_validate(skb, proto, false, false, 0, compute_pseudo)
|
|
|
|
#define skb_checksum_init_zero_check(skb, proto, check, compute_pseudo) \
|
|
__skb_checksum_validate(skb, proto, false, true, check, compute_pseudo)
|
|
|
|
#define skb_checksum_validate(skb, proto, compute_pseudo) \
|
|
__skb_checksum_validate(skb, proto, true, false, 0, compute_pseudo)
|
|
|
|
#define skb_checksum_validate_zero_check(skb, proto, check, \
|
|
compute_pseudo) \
|
|
__skb_checksum_validate(skb, proto, true, true, check, compute_pseudo)
|
|
|
|
#define skb_checksum_simple_validate(skb) \
|
|
__skb_checksum_validate(skb, 0, true, false, 0, null_compute_pseudo)
|
|
|
|
static inline bool __skb_checksum_convert_check(struct sk_buff *skb)
|
|
{
|
|
return (skb->ip_summed == CHECKSUM_NONE && skb->csum_valid);
|
|
}
|
|
|
|
static inline void __skb_checksum_convert(struct sk_buff *skb, __wsum pseudo)
|
|
{
|
|
skb->csum = ~pseudo;
|
|
skb->ip_summed = CHECKSUM_COMPLETE;
|
|
}
|
|
|
|
#define skb_checksum_try_convert(skb, proto, compute_pseudo) \
|
|
do { \
|
|
if (__skb_checksum_convert_check(skb)) \
|
|
__skb_checksum_convert(skb, compute_pseudo(skb, proto)); \
|
|
} while (0)
|
|
|
|
static inline void skb_remcsum_adjust_partial(struct sk_buff *skb, void *ptr,
|
|
u16 start, u16 offset)
|
|
{
|
|
skb->ip_summed = CHECKSUM_PARTIAL;
|
|
skb->csum_start = ((unsigned char *)ptr + start) - skb->head;
|
|
skb->csum_offset = offset - start;
|
|
}
|
|
|
|
/* Update skbuf and packet to reflect the remote checksum offload operation.
|
|
* When called, ptr indicates the starting point for skb->csum when
|
|
* ip_summed is CHECKSUM_COMPLETE. If we need create checksum complete
|
|
* here, skb_postpull_rcsum is done so skb->csum start is ptr.
|
|
*/
|
|
static inline void skb_remcsum_process(struct sk_buff *skb, void *ptr,
|
|
int start, int offset, bool nopartial)
|
|
{
|
|
__wsum delta;
|
|
|
|
if (!nopartial) {
|
|
skb_remcsum_adjust_partial(skb, ptr, start, offset);
|
|
return;
|
|
}
|
|
|
|
if (unlikely(skb->ip_summed != CHECKSUM_COMPLETE)) {
|
|
__skb_checksum_complete(skb);
|
|
skb_postpull_rcsum(skb, skb->data, ptr - (void *)skb->data);
|
|
}
|
|
|
|
delta = remcsum_adjust(ptr, skb->csum, start, offset);
|
|
|
|
/* Adjust skb->csum since we changed the packet */
|
|
skb->csum = csum_add(skb->csum, delta);
|
|
}
|
|
|
|
static inline struct nf_conntrack *skb_nfct(const struct sk_buff *skb)
|
|
{
|
|
#if IS_ENABLED(CONFIG_NF_CONNTRACK)
|
|
return (void *)(skb->_nfct & NFCT_PTRMASK);
|
|
#else
|
|
return NULL;
|
|
#endif
|
|
}
|
|
|
|
static inline unsigned long skb_get_nfct(const struct sk_buff *skb)
|
|
{
|
|
#if IS_ENABLED(CONFIG_NF_CONNTRACK)
|
|
return skb->_nfct;
|
|
#else
|
|
return 0UL;
|
|
#endif
|
|
}
|
|
|
|
static inline void skb_set_nfct(struct sk_buff *skb, unsigned long nfct)
|
|
{
|
|
#if IS_ENABLED(CONFIG_NF_CONNTRACK)
|
|
skb->_nfct = nfct;
|
|
#endif
|
|
}
|
|
|
|
#ifdef CONFIG_SKB_EXTENSIONS
|
|
enum skb_ext_id {
|
|
#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
|
|
SKB_EXT_BRIDGE_NF,
|
|
#endif
|
|
#ifdef CONFIG_XFRM
|
|
SKB_EXT_SEC_PATH,
|
|
#endif
|
|
#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
|
|
TC_SKB_EXT,
|
|
#endif
|
|
#if IS_ENABLED(CONFIG_MPTCP)
|
|
SKB_EXT_MPTCP,
|
|
#endif
|
|
SKB_EXT_NUM, /* must be last */
|
|
};
|
|
|
|
/**
|
|
* struct skb_ext - sk_buff extensions
|
|
* @refcnt: 1 on allocation, deallocated on 0
|
|
* @offset: offset to add to @data to obtain extension address
|
|
* @chunks: size currently allocated, stored in SKB_EXT_ALIGN_SHIFT units
|
|
* @data: start of extension data, variable sized
|
|
*
|
|
* Note: offsets/lengths are stored in chunks of 8 bytes, this allows
|
|
* to use 'u8' types while allowing up to 2kb worth of extension data.
|
|
*/
|
|
struct skb_ext {
|
|
refcount_t refcnt;
|
|
u8 offset[SKB_EXT_NUM]; /* in chunks of 8 bytes */
|
|
u8 chunks; /* same */
|
|
char data[] __aligned(8);
|
|
};
|
|
|
|
struct skb_ext *__skb_ext_alloc(gfp_t flags);
|
|
void *__skb_ext_set(struct sk_buff *skb, enum skb_ext_id id,
|
|
struct skb_ext *ext);
|
|
void *skb_ext_add(struct sk_buff *skb, enum skb_ext_id id);
|
|
void __skb_ext_del(struct sk_buff *skb, enum skb_ext_id id);
|
|
void __skb_ext_put(struct skb_ext *ext);
|
|
|
|
static inline void skb_ext_put(struct sk_buff *skb)
|
|
{
|
|
if (skb->active_extensions)
|
|
__skb_ext_put(skb->extensions);
|
|
}
|
|
|
|
static inline void __skb_ext_copy(struct sk_buff *dst,
|
|
const struct sk_buff *src)
|
|
{
|
|
dst->active_extensions = src->active_extensions;
|
|
|
|
if (src->active_extensions) {
|
|
struct skb_ext *ext = src->extensions;
|
|
|
|
refcount_inc(&ext->refcnt);
|
|
dst->extensions = ext;
|
|
}
|
|
}
|
|
|
|
static inline void skb_ext_copy(struct sk_buff *dst, const struct sk_buff *src)
|
|
{
|
|
skb_ext_put(dst);
|
|
__skb_ext_copy(dst, src);
|
|
}
|
|
|
|
static inline bool __skb_ext_exist(const struct skb_ext *ext, enum skb_ext_id i)
|
|
{
|
|
return !!ext->offset[i];
|
|
}
|
|
|
|
static inline bool skb_ext_exist(const struct sk_buff *skb, enum skb_ext_id id)
|
|
{
|
|
return skb->active_extensions & (1 << id);
|
|
}
|
|
|
|
static inline void skb_ext_del(struct sk_buff *skb, enum skb_ext_id id)
|
|
{
|
|
if (skb_ext_exist(skb, id))
|
|
__skb_ext_del(skb, id);
|
|
}
|
|
|
|
static inline void *skb_ext_find(const struct sk_buff *skb, enum skb_ext_id id)
|
|
{
|
|
if (skb_ext_exist(skb, id)) {
|
|
struct skb_ext *ext = skb->extensions;
|
|
|
|
return (void *)ext + (ext->offset[id] << 3);
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static inline void skb_ext_reset(struct sk_buff *skb)
|
|
{
|
|
if (unlikely(skb->active_extensions)) {
|
|
__skb_ext_put(skb->extensions);
|
|
skb->active_extensions = 0;
|
|
}
|
|
}
|
|
|
|
static inline bool skb_has_extensions(struct sk_buff *skb)
|
|
{
|
|
return unlikely(skb->active_extensions);
|
|
}
|
|
#else
|
|
static inline void skb_ext_put(struct sk_buff *skb) {}
|
|
static inline void skb_ext_reset(struct sk_buff *skb) {}
|
|
static inline void skb_ext_del(struct sk_buff *skb, int unused) {}
|
|
static inline void __skb_ext_copy(struct sk_buff *d, const struct sk_buff *s) {}
|
|
static inline void skb_ext_copy(struct sk_buff *dst, const struct sk_buff *s) {}
|
|
static inline bool skb_has_extensions(struct sk_buff *skb) { return false; }
|
|
#endif /* CONFIG_SKB_EXTENSIONS */
|
|
|
|
static inline void nf_reset_ct(struct sk_buff *skb)
|
|
{
|
|
#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
|
|
nf_conntrack_put(skb_nfct(skb));
|
|
skb->_nfct = 0;
|
|
#endif
|
|
}
|
|
|
|
static inline void nf_reset_trace(struct sk_buff *skb)
|
|
{
|
|
#if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE) || defined(CONFIG_NF_TABLES)
|
|
skb->nf_trace = 0;
|
|
#endif
|
|
}
|
|
|
|
static inline void ipvs_reset(struct sk_buff *skb)
|
|
{
|
|
#if IS_ENABLED(CONFIG_IP_VS)
|
|
skb->ipvs_property = 0;
|
|
#endif
|
|
}
|
|
|
|
/* Note: This doesn't put any conntrack info in dst. */
|
|
static inline void __nf_copy(struct sk_buff *dst, const struct sk_buff *src,
|
|
bool copy)
|
|
{
|
|
#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
|
|
dst->_nfct = src->_nfct;
|
|
nf_conntrack_get(skb_nfct(src));
|
|
#endif
|
|
#if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE) || defined(CONFIG_NF_TABLES)
|
|
if (copy)
|
|
dst->nf_trace = src->nf_trace;
|
|
#endif
|
|
}
|
|
|
|
static inline void nf_copy(struct sk_buff *dst, const struct sk_buff *src)
|
|
{
|
|
#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
|
|
nf_conntrack_put(skb_nfct(dst));
|
|
#endif
|
|
__nf_copy(dst, src, true);
|
|
}
|
|
|
|
#ifdef CONFIG_NETWORK_SECMARK
|
|
static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from)
|
|
{
|
|
to->secmark = from->secmark;
|
|
}
|
|
|
|
static inline void skb_init_secmark(struct sk_buff *skb)
|
|
{
|
|
skb->secmark = 0;
|
|
}
|
|
#else
|
|
static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from)
|
|
{ }
|
|
|
|
static inline void skb_init_secmark(struct sk_buff *skb)
|
|
{ }
|
|
#endif
|
|
|
|
static inline int secpath_exists(const struct sk_buff *skb)
|
|
{
|
|
#ifdef CONFIG_XFRM
|
|
return skb_ext_exist(skb, SKB_EXT_SEC_PATH);
|
|
#else
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
static inline bool skb_irq_freeable(const struct sk_buff *skb)
|
|
{
|
|
return !skb->destructor &&
|
|
!secpath_exists(skb) &&
|
|
!skb_nfct(skb) &&
|
|
!skb->_skb_refdst &&
|
|
!skb_has_frag_list(skb);
|
|
}
|
|
|
|
static inline void skb_set_queue_mapping(struct sk_buff *skb, u16 queue_mapping)
|
|
{
|
|
skb->queue_mapping = queue_mapping;
|
|
}
|
|
|
|
static inline u16 skb_get_queue_mapping(const struct sk_buff *skb)
|
|
{
|
|
return skb->queue_mapping;
|
|
}
|
|
|
|
static inline void skb_copy_queue_mapping(struct sk_buff *to, const struct sk_buff *from)
|
|
{
|
|
to->queue_mapping = from->queue_mapping;
|
|
}
|
|
|
|
static inline void skb_record_rx_queue(struct sk_buff *skb, u16 rx_queue)
|
|
{
|
|
skb->queue_mapping = rx_queue + 1;
|
|
}
|
|
|
|
static inline u16 skb_get_rx_queue(const struct sk_buff *skb)
|
|
{
|
|
return skb->queue_mapping - 1;
|
|
}
|
|
|
|
static inline bool skb_rx_queue_recorded(const struct sk_buff *skb)
|
|
{
|
|
return skb->queue_mapping != 0;
|
|
}
|
|
|
|
static inline void skb_set_dst_pending_confirm(struct sk_buff *skb, u32 val)
|
|
{
|
|
skb->dst_pending_confirm = val;
|
|
}
|
|
|
|
static inline bool skb_get_dst_pending_confirm(const struct sk_buff *skb)
|
|
{
|
|
return skb->dst_pending_confirm != 0;
|
|
}
|
|
|
|
static inline struct sec_path *skb_sec_path(const struct sk_buff *skb)
|
|
{
|
|
#ifdef CONFIG_XFRM
|
|
return skb_ext_find(skb, SKB_EXT_SEC_PATH);
|
|
#else
|
|
return NULL;
|
|
#endif
|
|
}
|
|
|
|
/* Keeps track of mac header offset relative to skb->head.
|
|
* It is useful for TSO of Tunneling protocol. e.g. GRE.
|
|
* For non-tunnel skb it points to skb_mac_header() and for
|
|
* tunnel skb it points to outer mac header.
|
|
* Keeps track of level of encapsulation of network headers.
|
|
*/
|
|
struct skb_gso_cb {
|
|
union {
|
|
int mac_offset;
|
|
int data_offset;
|
|
};
|
|
int encap_level;
|
|
__wsum csum;
|
|
__u16 csum_start;
|
|
};
|
|
#define SKB_GSO_CB_OFFSET 32
|
|
#define SKB_GSO_CB(skb) ((struct skb_gso_cb *)((skb)->cb + SKB_GSO_CB_OFFSET))
|
|
|
|
static inline int skb_tnl_header_len(const struct sk_buff *inner_skb)
|
|
{
|
|
return (skb_mac_header(inner_skb) - inner_skb->head) -
|
|
SKB_GSO_CB(inner_skb)->mac_offset;
|
|
}
|
|
|
|
static inline int gso_pskb_expand_head(struct sk_buff *skb, int extra)
|
|
{
|
|
int new_headroom, headroom;
|
|
int ret;
|
|
|
|
headroom = skb_headroom(skb);
|
|
ret = pskb_expand_head(skb, extra, 0, GFP_ATOMIC);
|
|
if (ret)
|
|
return ret;
|
|
|
|
new_headroom = skb_headroom(skb);
|
|
SKB_GSO_CB(skb)->mac_offset += (new_headroom - headroom);
|
|
return 0;
|
|
}
|
|
|
|
static inline void gso_reset_checksum(struct sk_buff *skb, __wsum res)
|
|
{
|
|
/* Do not update partial checksums if remote checksum is enabled. */
|
|
if (skb->remcsum_offload)
|
|
return;
|
|
|
|
SKB_GSO_CB(skb)->csum = res;
|
|
SKB_GSO_CB(skb)->csum_start = skb_checksum_start(skb) - skb->head;
|
|
}
|
|
|
|
/* Compute the checksum for a gso segment. First compute the checksum value
|
|
* from the start of transport header to SKB_GSO_CB(skb)->csum_start, and
|
|
* then add in skb->csum (checksum from csum_start to end of packet).
|
|
* skb->csum and csum_start are then updated to reflect the checksum of the
|
|
* resultant packet starting from the transport header-- the resultant checksum
|
|
* is in the res argument (i.e. normally zero or ~ of checksum of a pseudo
|
|
* header.
|
|
*/
|
|
static inline __sum16 gso_make_checksum(struct sk_buff *skb, __wsum res)
|
|
{
|
|
unsigned char *csum_start = skb_transport_header(skb);
|
|
int plen = (skb->head + SKB_GSO_CB(skb)->csum_start) - csum_start;
|
|
__wsum partial = SKB_GSO_CB(skb)->csum;
|
|
|
|
SKB_GSO_CB(skb)->csum = res;
|
|
SKB_GSO_CB(skb)->csum_start = csum_start - skb->head;
|
|
|
|
return csum_fold(csum_partial(csum_start, plen, partial));
|
|
}
|
|
|
|
static inline bool skb_is_gso(const struct sk_buff *skb)
|
|
{
|
|
return skb_shinfo(skb)->gso_size;
|
|
}
|
|
|
|
/* Note: Should be called only if skb_is_gso(skb) is true */
|
|
static inline bool skb_is_gso_v6(const struct sk_buff *skb)
|
|
{
|
|
return skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6;
|
|
}
|
|
|
|
/* Note: Should be called only if skb_is_gso(skb) is true */
|
|
static inline bool skb_is_gso_sctp(const struct sk_buff *skb)
|
|
{
|
|
return skb_shinfo(skb)->gso_type & SKB_GSO_SCTP;
|
|
}
|
|
|
|
/* Note: Should be called only if skb_is_gso(skb) is true */
|
|
static inline bool skb_is_gso_tcp(const struct sk_buff *skb)
|
|
{
|
|
return skb_shinfo(skb)->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6);
|
|
}
|
|
|
|
static inline void skb_gso_reset(struct sk_buff *skb)
|
|
{
|
|
skb_shinfo(skb)->gso_size = 0;
|
|
skb_shinfo(skb)->gso_segs = 0;
|
|
skb_shinfo(skb)->gso_type = 0;
|
|
}
|
|
|
|
static inline void skb_increase_gso_size(struct skb_shared_info *shinfo,
|
|
u16 increment)
|
|
{
|
|
if (WARN_ON_ONCE(shinfo->gso_size == GSO_BY_FRAGS))
|
|
return;
|
|
shinfo->gso_size += increment;
|
|
}
|
|
|
|
static inline void skb_decrease_gso_size(struct skb_shared_info *shinfo,
|
|
u16 decrement)
|
|
{
|
|
if (WARN_ON_ONCE(shinfo->gso_size == GSO_BY_FRAGS))
|
|
return;
|
|
shinfo->gso_size -= decrement;
|
|
}
|
|
|
|
void __skb_warn_lro_forwarding(const struct sk_buff *skb);
|
|
|
|
static inline bool skb_warn_if_lro(const struct sk_buff *skb)
|
|
{
|
|
/* LRO sets gso_size but not gso_type, whereas if GSO is really
|
|
* wanted then gso_type will be set. */
|
|
const struct skb_shared_info *shinfo = skb_shinfo(skb);
|
|
|
|
if (skb_is_nonlinear(skb) && shinfo->gso_size != 0 &&
|
|
unlikely(shinfo->gso_type == 0)) {
|
|
__skb_warn_lro_forwarding(skb);
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
static inline void skb_forward_csum(struct sk_buff *skb)
|
|
{
|
|
/* Unfortunately we don't support this one. Any brave souls? */
|
|
if (skb->ip_summed == CHECKSUM_COMPLETE)
|
|
skb->ip_summed = CHECKSUM_NONE;
|
|
}
|
|
|
|
/**
|
|
* skb_checksum_none_assert - make sure skb ip_summed is CHECKSUM_NONE
|
|
* @skb: skb to check
|
|
*
|
|
* fresh skbs have their ip_summed set to CHECKSUM_NONE.
|
|
* Instead of forcing ip_summed to CHECKSUM_NONE, we can
|
|
* use this helper, to document places where we make this assertion.
|
|
*/
|
|
static inline void skb_checksum_none_assert(const struct sk_buff *skb)
|
|
{
|
|
#ifdef DEBUG
|
|
BUG_ON(skb->ip_summed != CHECKSUM_NONE);
|
|
#endif
|
|
}
|
|
|
|
bool skb_partial_csum_set(struct sk_buff *skb, u16 start, u16 off);
|
|
|
|
int skb_checksum_setup(struct sk_buff *skb, bool recalculate);
|
|
struct sk_buff *skb_checksum_trimmed(struct sk_buff *skb,
|
|
unsigned int transport_len,
|
|
__sum16(*skb_chkf)(struct sk_buff *skb));
|
|
|
|
/**
|
|
* skb_head_is_locked - Determine if the skb->head is locked down
|
|
* @skb: skb to check
|
|
*
|
|
* The head on skbs build around a head frag can be removed if they are
|
|
* not cloned. This function returns true if the skb head is locked down
|
|
* due to either being allocated via kmalloc, or by being a clone with
|
|
* multiple references to the head.
|
|
*/
|
|
static inline bool skb_head_is_locked(const struct sk_buff *skb)
|
|
{
|
|
return !skb->head_frag || skb_cloned(skb);
|
|
}
|
|
|
|
/* Local Checksum Offload.
|
|
* Compute outer checksum based on the assumption that the
|
|
* inner checksum will be offloaded later.
|
|
* See Documentation/networking/checksum-offloads.rst for
|
|
* explanation of how this works.
|
|
* Fill in outer checksum adjustment (e.g. with sum of outer
|
|
* pseudo-header) before calling.
|
|
* Also ensure that inner checksum is in linear data area.
|
|
*/
|
|
static inline __wsum lco_csum(struct sk_buff *skb)
|
|
{
|
|
unsigned char *csum_start = skb_checksum_start(skb);
|
|
unsigned char *l4_hdr = skb_transport_header(skb);
|
|
__wsum partial;
|
|
|
|
/* Start with complement of inner checksum adjustment */
|
|
partial = ~csum_unfold(*(__force __sum16 *)(csum_start +
|
|
skb->csum_offset));
|
|
|
|
/* Add in checksum of our headers (incl. outer checksum
|
|
* adjustment filled in by caller) and return result.
|
|
*/
|
|
return csum_partial(l4_hdr, csum_start - l4_hdr, partial);
|
|
}
|
|
|
|
static inline bool skb_is_redirected(const struct sk_buff *skb)
|
|
{
|
|
#ifdef CONFIG_NET_REDIRECT
|
|
return skb->redirected;
|
|
#else
|
|
return false;
|
|
#endif
|
|
}
|
|
|
|
static inline void skb_set_redirected(struct sk_buff *skb, bool from_ingress)
|
|
{
|
|
#ifdef CONFIG_NET_REDIRECT
|
|
skb->redirected = 1;
|
|
skb->from_ingress = from_ingress;
|
|
if (skb->from_ingress)
|
|
skb->tstamp = 0;
|
|
#endif
|
|
}
|
|
|
|
static inline void skb_reset_redirect(struct sk_buff *skb)
|
|
{
|
|
#ifdef CONFIG_NET_REDIRECT
|
|
skb->redirected = 0;
|
|
#endif
|
|
}
|
|
|
|
static inline bool skb_csum_is_sctp(struct sk_buff *skb)
|
|
{
|
|
return skb->csum_not_inet;
|
|
}
|
|
|
|
static inline void skb_set_kcov_handle(struct sk_buff *skb,
|
|
const u64 kcov_handle)
|
|
{
|
|
#ifdef CONFIG_KCOV
|
|
skb->kcov_handle = kcov_handle;
|
|
#endif
|
|
}
|
|
|
|
static inline u64 skb_get_kcov_handle(struct sk_buff *skb)
|
|
{
|
|
#ifdef CONFIG_KCOV
|
|
return skb->kcov_handle;
|
|
#else
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
#endif /* __KERNEL__ */
|
|
#endif /* _LINUX_SKBUFF_H */
|