path: root/platform/linux-generic/include/api/odp_packet.h

/* Copyright (c) 2013, Linaro Limited
 * All rights reserved.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */


/**
 * @file
 *
 * ODP packet descriptor
 */

#ifndef ODP_PACKET_H_
#define ODP_PACKET_H_

#ifdef __cplusplus
extern "C" {
#endif

#include <odp_buffer.h>
#include <odp_platform_types.h>

/** @defgroup odp_packet ODP PACKET
 *  Operations on a packet.
 *  @{
 */


/*
 * Packet API v0.5 notes
 * - Push/pull operations only on packet level
 * - Push/pull within limits of segment headroom/tailroom/data lengths
 * - Segment data length must be always at least one byte (i.e. there are no
 *   empty segments)
 * - Head/tailroom content belong to packet content (in addition to data
 *   and meta-data) and thus is preserved over packet ownership changes.
 * - _addr refer to a fixed address, which operations do not modify
 * - _ptr refer to pointer to data, which may be modified by operations
 */


/*
 *
 * Alloc and free
 * ********************************************************
 *
 */

/**
 * Allocate a packet from a buffer pool
 *
 * Allocates a packet of the requested length from the specified buffer pool.
 * Pool must have been created with buffer type ODP_BUFFER_TYPE_PACKET. The
 * packet is initialized with data pointers and lengths set according to the
 * specified len, and the default headroom and tailroom length settings. All
 * other packet metadata are set to their default values.
 *
 * @param pool          Pool handle
 * @param len           Packet data length
 *
 * @return Handle of allocated packet
 * @retval ODP_PACKET_INVALID  Packet could not be allocated
 *
 * @note The default headroom and tailroom used for packets is specified by
 * the ODP_CONFIG_PACKET_HEADROOM and ODP_CONFIG_PACKET_TAILROOM defines in
 * odp_config.h.
 */
odp_packet_t odp_packet_alloc(odp_buffer_pool_t pool, uint32_t len);

/**
 * Free packet
 *
 * Frees the packet into the buffer pool it was allocated from.
 *
 * @param pkt           Packet handle
 */
void odp_packet_free(odp_packet_t pkt);

/**
 * Reset packet
 *
 * Resets all packet meta-data to their default values. Packet length is used
 * to initialize pointers and lengths. It must be less than the total buffer
 * length of the packet minus the default headroom length. Packet is not
 * modified on failure.
 *
 * @param pkt           Packet handle
 * @param len           Packet data length
 *
 * @retval 0 Success
 * @retval Non-zero Failure
 *
 * @see odp_packet_buf_len()
 */
int odp_packet_reset(odp_packet_t pkt, uint32_t len);

/**
 * Convert a buffer handle to a packet handle
 *
 * @param buf  Buffer handle
 *
 * @return Packet handle
 */
odp_packet_t odp_packet_from_buffer(odp_buffer_t buf);

/**
 * Convert a packet handle to a buffer handle
 *
 * @param pkt  Packet handle
 *
 * @return Buffer handle
 */
odp_buffer_t odp_packet_to_buffer(odp_packet_t pkt);


/*
 *
 * Pointers and lengths
 * ********************************************************
 *
 */

/**
 * Packet head address
 *
 * Returns start address of the first segment. Packet level headroom starts
 * from here. Use odp_packet_data() or odp_packet_l2_ptr() to return the
 * packet data start address.
 *
 * @param pkt  Packet handle
 *
 * @return Pointer to the start address of the first packet segment
 *
 * @see odp_packet_data(), odp_packet_l2_ptr(), odp_packet_headroom()
 */
void *odp_packet_head(odp_packet_t pkt);

/**
 * Total packet buffer length
 *
 * Returns sum of buffer lengths over all packet segments.
 *
 * @param pkt  Packet handle
 *
 * @return  Total packet buffer length in bytes
 *
 * @see odp_packet_reset()
 */
uint32_t odp_packet_buf_len(odp_packet_t pkt);

/**
 * Packet data pointer
 *
 * Returns the current packet data pointer. When a packet is received
 * from packet input, this points to the first byte of the received
 * packet. Packet level offsets are calculated relative to this position.
 *
 * User can adjust the data pointer with head_push/head_pull (does not modify
 * segmentation) and add_data/rem_data calls (may modify segmentation).
 *
 * @param pkt  Packet handle
 *
 * @return  Pointer to the packet data
 *
 * @see odp_packet_l2_ptr(), odp_packet_seg_len()
 */
void *odp_packet_data(odp_packet_t pkt);

/**
 * Packet segment data length
 *
 * Returns number of data bytes following the current data pointer
 * (odp_packet_data()) location in the segment.
 *
 * @param pkt  Packet handle
 *
 * @return  Segment data length in bytes (pointed by odp_packet_data())
 *
 * @see odp_packet_data()
 */
uint32_t odp_packet_seg_len(odp_packet_t pkt);

/**
 * Packet data length
 *
 * Returns sum of data lengths over all packet segments.
 *
 * @param pkt  Packet handle
 *
 * @return Packet data length
 */
uint32_t odp_packet_len(odp_packet_t pkt);

/**
 * Packet headroom length
 *
 * Returns the current packet level headroom length.
 *
 * @param pkt  Packet handle
 *
 * @return Headroom length
 */
uint32_t odp_packet_headroom(odp_packet_t pkt);

/**
 * Packet tailroom length
 *
 * Returns the current packet level tailroom length.
 *
 * @param pkt  Packet handle
 *
 * @return Tailroom length
 */
uint32_t odp_packet_tailroom(odp_packet_t pkt);

/**
 * Packet tailroom pointer
 *
 * Returns pointer to the start of the current packet level tailroom.
 *
 * User can adjust the tail pointer with tail_push/tail_pull (does not modify
 * segmentation) and add_data/rem_data calls (may modify segmentation).
 *
 * @param pkt  Packet handle
 *
 * @return  Tailroom pointer
 *
 * @see odp_packet_tailroom()
 */
void *odp_packet_tail(odp_packet_t pkt);

/**
 * Push out packet head
 *
 * Increase packet data length by moving packet head into packet headroom.
 * Packet headroom is decreased with the same amount. The packet head may be
 * pushed out up to 'headroom' bytes. Packet is not modified if there's not
 * enough headroom space.
 *
 * odp_packet_xxx:
 * seg_len  += len
 * len      += len
 * headroom -= len
 * data     -= len
 *
 * Operation does not modify packet segmentation or move data. Handles and
 * pointers remain valid. User is responsible to update packet meta-data
 * offsets when needed.
 *
 * @param pkt  Packet handle
 * @param len  Number of bytes to push the head (0 ... headroom)
 *
 * @return The new data pointer
 * @retval NULL  Requested offset exceeds available headroom
 *
 * @see odp_packet_headroom(), odp_packet_pull_head()
 */
void *odp_packet_push_head(odp_packet_t pkt, uint32_t len);

/**
 * Pull in packet head
 *
 * Decrease packet data length by removing data from the head of the packet.
 * Packet headroom is increased with the same amount. Packet head may be pulled
 * in up to seg_len - 1 bytes (i.e. packet data pointer must stay in the
 * first segment). Packet is not modified if there's not enough data.
 *
 * odp_packet_xxx:
 * seg_len  -= len
 * len      -= len
 * headroom += len
 * data     += len
 *
 * Operation does not modify packet segmentation or move data. Handles and
 * pointers remain valid. User is responsible to update packet meta-data
 * offsets when needed.
 *
 * @param pkt  Packet handle
 * @param len  Number of bytes to pull the head (0 ... seg_len - 1)
 *
 * @return The new data pointer, or NULL in case of an error.
 * @retval NULL  Requested offset exceeds packet segment length
 *
 * @see odp_packet_seg_len(), odp_packet_push_head()
 */
void *odp_packet_pull_head(odp_packet_t pkt, uint32_t len);

/**
 * Push out packet tail
 *
 * Increase packet data length by moving packet tail into packet tailroom.
 * Packet tailroom is decreased with the same amount. The packet tail may be
 * pushed out up to 'tailroom' bytes. Packet is not modified if there's not
 * enough tailroom.
 *
 * last_seg:
 * data_len += len
 *
 * odp_packet_xxx:
 * len      += len
 * tail     += len
 * tailroom -= len
 *
 * Operation does not modify packet segmentation or move data. Handles,
 * pointers and offsets remain valid.
 *
 * @param pkt  Packet handle
 * @param len  Number of bytes to push the tail (0 ... tailroom)
 *
 * @return The old tail pointer
 * @retval NULL  Requested offset exceeds available tailroom
 *
 * @see odp_packet_tailroom(), odp_packet_pull_tail()
 */
void *odp_packet_push_tail(odp_packet_t pkt, uint32_t len);

/**
 * Pull in packet tail
 *
 * Decrease packet data length by removing data from the tail of the packet.
 * Packet tailroom is increased with the same amount. Packet tail may be pulled
 * in up to last segment data_len - 1 bytes. (i.e. packet tail must stay in the
 * last segment). Packet is not modified if there's not enough data.
 *
 * last_seg:
 * data_len -= len
 *
 * odp_packet_xxx:
 * len      -= len
 * tail     -= len
 * tailroom += len
 *
 * Operation does not modify packet segmentation or move data. Handles and
 * pointers remain valid. User is responsible to update packet meta-data
 * offsets when needed.
 *
 * @param pkt  Packet handle
 * @param len  Number of bytes to pull the tail (0 ... last_seg:data_len - 1)
 *
 * @return The new tail pointer
 * @retval NULL  The specified offset exceeds allowable data length
 */
void *odp_packet_pull_tail(odp_packet_t pkt, uint32_t len);

/**
 * Packet offset pointer
 *
 * Returns pointer to data in the packet offset. The packet level byte offset is
 * calculated from the current odp_packet_data() position. Optionally outputs
 * handle to the segment and number of data bytes in the segment following the
 * pointer.
 *
 * @param      pkt      Packet handle
 * @param      offset   Byte offset into the packet
 * @param[out] len      Number of data bytes remaining in the segment (output).
 *                      Ignored when NULL.
 * @param[out] seg      Handle to the segment containing the address (output).
 *                      Ignored when NULL.
 *
 * @return Pointer to the offset
 * @retval NULL  Requested offset exceeds packet length
 */
void *odp_packet_offset(odp_packet_t pkt, uint32_t offset, uint32_t *len,
			odp_packet_seg_t *seg);

/*
 *
 * Meta-data
 * ********************************************************
 *
 */

/**
 * Packet pool
 *
 * Returns handle to the buffer pool where the packet was allocated from.
 *
 * @param pkt   Packet handle
 *
 * @return Buffer pool handle
 */
odp_buffer_pool_t odp_packet_pool(odp_packet_t pkt);

/**
 * Packet input interface
 *
 * Returns handle to the packet IO interface which received the packet or
 * ODP_PKTIO_INVALID when the packet was allocated/reset by the application.
 *
 * @param pkt   Packet handle
 *
 * @return Packet interface handle
 * @retval ODP_PKTIO_INVALID  Packet was not received
 */
odp_pktio_t odp_packet_input(odp_packet_t pkt);

/**
 * User context pointer
 *
 * Return previously stored user context pointer.
 *
 * @param pkt  Packet handle
 *
 * @return User context pointer
 */
void *odp_packet_user_ptr(odp_packet_t pkt);

/**
 * Set user context pointer
 *
 * Each packet has room for a user defined context. The context can be stored
 * either as a pointer OR as a uint64_t value, but not both at the same time.
 * The latest context set operation determines which one has been stored.
 *
 * @param pkt  Packet handle
 * @param ctx  User context pointer
 */
void odp_packet_user_ptr_set(odp_packet_t pkt, const void *ctx);

/**
 * User context data (uint64_t)
 *
 * Return previously stored user context uint64_t value.
 *
 * @param pkt  Packet handle
 *
 * @return User context data
 */
uint64_t odp_packet_user_u64(odp_packet_t pkt);

/**
 * Set user context data (uint64_t)
 *
 * Each packet has room for a user defined context. The context can be stored
 * either as a pointer OR as a uint64_t value, but not both at the same time.
 * The latest context set operation determines which one has been stored.
 *
 * @param pkt  Packet handle
 * @param ctx  User context data
 */
void odp_packet_user_u64_set(odp_packet_t pkt, uint64_t ctx);

/**
 * Layer 2 start pointer
 *
 * Returns pointer to the start of the layer 2 header. Optionally, outputs
 * number of data bytes in the segment following the pointer.
 *
 * @param      pkt      Packet handle
 * @param[out] len      Number of data bytes remaining in the segment (output).
 *                      Ignored when NULL.
 *
 * @return  Layer 2 start pointer, or offset 0 by default
 *
 * @see odp_packet_l2_offset(), odp_packet_l2_offset_set()
 */
void *odp_packet_l2_ptr(odp_packet_t pkt, uint32_t *len);

/**
 * Layer 2 start offset
 *
 * Returns offset to the start of the layer 2 header. The offset is calculated
 * from the current odp_packet_data() position in bytes.
 *
 * User is responsible to update the offset when modifying the packet data
 * pointer position.
 *
 * @param pkt  Packet handle
 *
 * @return  Layer 2 start offset
 */
uint32_t odp_packet_l2_offset(odp_packet_t pkt);

/**
 * Set layer 2 start offset
 *
 * Set offset to the start of the layer 2 header. The offset is calculated from
 * the current odp_packet_data() position in bytes. Offset must not exceed
 * packet data length. Packet is not modified on an error.
 *
 * @param pkt     Packet handle
 * @param offset  Layer 2 start offset (0 ... odp_packet_len()-1)
 *
 * @retval 0 Success
 * @retval Non-zero Failure
 */
int odp_packet_l2_offset_set(odp_packet_t pkt, uint32_t offset);

/**
 * Layer 3 start pointer
 *
 * Returns pointer to the start of the layer 3 header. Optionally, outputs
 * number of data bytes in the segment following the pointer.
 *
 * @param      pkt      Packet handle
 * @param[out] len      Number of data bytes remaining in the segment (output).
 *                      Ignored when NULL.
 *
 * @return  Layer 3 start pointer, or NULL
 *
 * @see odp_packet_l3_offset(), odp_packet_l3_offset_set()
 */
void *odp_packet_l3_ptr(odp_packet_t pkt, uint32_t *len);

/**
 * Layer 3 start offset
 *
 * Returns offset to the start of the layer 3 header. The offset is calculated
 * from the current odp_packet_data() position in bytes.
 *
 * User is responsible to update the offset when modifying the packet data
 * pointer position.
 *
 * @param pkt  Packet handle
 *
 * @return  Layer 3 start offset or ODP_PACKET_OFFSET_INVALID if not found
 */
uint32_t odp_packet_l3_offset(odp_packet_t pkt);

/**
 * Set layer 3 start offset
 *
 * Set offset to the start of the layer 3 header. The offset is calculated from
 * the current odp_packet_data() position in bytes. Offset must not exceed
 * packet data length. Packet is not modified on an error.
 *
 * @param pkt     Packet handle
 * @param offset  Layer 3 start offset (0 ... odp_packet_len()-1)
 *
 * @retval 0 Success
 * @retval Non-zero Failure
 */
int odp_packet_l3_offset_set(odp_packet_t pkt, uint32_t offset);

/**
 * Layer 4 start pointer
 *
 * Returns pointer to the start of the layer 4 header. Optionally, outputs
 * number of data bytes in the segment following the pointer.
 *
 * @param      pkt      Packet handle
 * @param[out] len      Number of data bytes remaining in the segment (output).
 *                      Ignored when NULL.
 *
 * @return  Layer 4 start pointer, or NULL
 *
 * @see odp_packet_l4_offset(), odp_packet_l4_offset_set()
 */
void *odp_packet_l4_ptr(odp_packet_t pkt, uint32_t *len);

/**
 * Layer 4 start offset
 *
 * Returns offset to the start of the layer 4 header. The offset is calculated
 * from the current odp_packet_data() position in bytes.
 *
 * User is responsible to update the offset when modifying the packet data
 * pointer position.
 *
 * @param pkt  Packet handle
 *
 * @return  Layer 4 start offset or ODP_PACKET_OFFSET_INVALID if not found
 */
uint32_t odp_packet_l4_offset(odp_packet_t pkt);

/**
 * Set layer 4 start offset
 *
 * Set offset to the start of the layer 4 header. The offset is calculated from
 * the current odp_packet_data() position in bytes. Offset must not exceed
 * packet data length. Packet is not modified on an error.
 *
 * @param pkt     Packet handle
 * @param offset  Layer 4 start offset (0 ... odp_packet_len()-1)
 *
 * @retval 0 Success
 * @retval Non-zero Failure
 */
int odp_packet_l4_offset_set(odp_packet_t pkt, uint32_t offset);

/**
 * Tests if packet is segmented
 *
 * @param pkt  Packet handle
 *
 * @retval 0 Packet is not segmented
 * @retval 1 Packet is segmented
 */
int odp_packet_is_segmented(odp_packet_t pkt);

/**
 * Number of segments
 *
 * Returns number of segments in the packet. A packet has always at least one
 * segment.
 *
 * @param pkt  Packet handle
 *
 * @return Number of segments (>0)
 */
int odp_packet_num_segs(odp_packet_t pkt);

/**
 * First segment in packet
 *
 * A packet has always the first segment (has at least one segment).
 *
 * @param pkt  Packet handle
 *
 * @return Handle to the first segment
 */
odp_packet_seg_t odp_packet_first_seg(odp_packet_t pkt);

/**
 * Last segment in packet
 *
 * A packet has always the last segment (has at least one segment).
 *
 * @param pkt  Packet handle
 *
 * @return Handle to the last segment
 */
odp_packet_seg_t odp_packet_last_seg(odp_packet_t pkt);

/**
 * Next segment in packet
 *
 * Returns handle to the next segment after the current segment, or
 * ODP_PACKET_SEG_INVALID if there are no more segments. Use
 * odp_packet_first_seg() to get handle to the first segment.
 *
 * @param pkt   Packet handle
 * @param seg   Current segment handle
 *
 * @return Handle to the next segment, or ODP_PACKET_SEG_INVALID
 */
odp_packet_seg_t odp_packet_next_seg(odp_packet_t pkt, odp_packet_seg_t seg);


/*
 *
 * Segment level
 * ********************************************************
 *
 */

/**
 * Segment buffer address
 *
 * Returns start address of the segment.
 *
 * @param pkt  Packet handle
 * @param seg  Segment handle
 *
 * @return  Start address of the segment, or NULL on an error
 *
 * @see odp_packet_seg_buf_len()
 */
void *odp_packet_seg_buf_addr(odp_packet_t pkt, odp_packet_seg_t seg);

/**
 * Segment buffer length
 *
 * Returns segment buffer length in bytes.
 *
 * @param pkt  Packet handle
 * @param seg  Segment handle
 *
 * @return  Segment buffer length in bytes
 *
 * @see odp_packet_seg_buf_addr()
 */
uint32_t odp_packet_seg_buf_len(odp_packet_t pkt, odp_packet_seg_t seg);

/**
 * Segment data pointer
 *
 * Returns pointer to the first byte of data in the segment.
 *
 * @param pkt  Packet handle
 * @param seg  Segment handle
 *
 * @return  Pointer to the segment data, or NULL on an error
 *
 * @see odp_packet_seg_data_len()
 */
void *odp_packet_seg_data(odp_packet_t pkt, odp_packet_seg_t seg);

/**
 * Segment data length
 *
 * Returns segment data length in bytes.
 *
 * @param pkt  Packet handle
 * @param seg  Segment handle
 *
 * @return  Segment data length in bytes
 *
 * @see odp_packet_seg_data()
 */
uint32_t odp_packet_seg_data_len(odp_packet_t pkt, odp_packet_seg_t seg);


/*
 *
 * Manipulation
 * ********************************************************
 *
 */


/**
 * Add data into an offset
 *
 * Increases packet data length by adding new data area into the specified
 * offset. The operation returns a new packet handle on success. It may modify
 * packet segmentation and move data. Handles and pointers must be updated
 * after the operation. User is responsible to update packet meta-data offsets
 * when needed. The packet is not modified on an error.
 *
 * @param pkt     Packet handle
 * @param offset  Byte offset into the packet
 * @param len     Number of bytes to add into the offset
 *
 * @return New packet handle, or ODP_PACKET_INVALID in case of an error.
 */
odp_packet_t odp_packet_add_data(odp_packet_t pkt, uint32_t offset,
				 uint32_t len);

/**
 * Remove data from an offset
 *
 * Decreases packet data length by removing data from the specified offset.
 * The operation returns a new packet handle on success, and may modify
 * packet segmentation and move data. Handles and pointers must be updated
 * after the operation. User is responsible to update packet meta-data offsets
 * when needed. The packet is not modified on an error.
 *
 * @param pkt     Packet handle
 * @param offset  Byte offset into the packet
 * @param len     Number of bytes to remove from the offset
 *
 * @return New packet handle, or ODP_PACKET_INVALID in case of an error.
 */
odp_packet_t odp_packet_rem_data(odp_packet_t pkt, uint32_t offset,
				 uint32_t len);


/*
 *
 * Copy
 * ********************************************************
 *
 */

/**
 * Copy packet
 *
 * Create a new copy of the packet. The new packet is exact copy of the source
 * packet (incl. data and meta-data). The pool must have been created with
 * buffer type ODP_BUFFER_TYPE_PACKET.
 *
 * @param pkt   Packet handle
 * @param pool  Buffer pool for allocation of the new packet.
 *
 * @return Handle to the copy of the packet, or ODP_PACKET_INVALID
 */
odp_packet_t odp_packet_copy(odp_packet_t pkt, odp_buffer_pool_t pool);

/**
 * Copy data from packet
 *
 * Copy    'len' bytes of data from the packet level offset to the destination
 * address.
 *
 * @param pkt    Packet handle
 * @param offset Byte offset into the packet
 * @param len    Number of bytes to copy
 * @param dst    Destination address
 *
 * @retval 0 Success
 * @retval Non-zero Failure
 */
int odp_packet_copydata_out(odp_packet_t pkt, uint32_t offset,
			    uint32_t len, void *dst);

/**
 * Copy data into packet
 *
 * Copy    'len' bytes of data from the source address into the packet level
 * offset. Maximum number of bytes to copy is packet data length minus the
 * offset. Packet is not modified on an error.
 *
 * @param pkt    Packet handle
 * @param offset Byte offset into the packet
 * @param len    Number of bytes to copy
 * @param src    Source address
 *
 * @retval 0 Success
 * @retval Non-zero Failure
 */
int odp_packet_copydata_in(odp_packet_t pkt, uint32_t offset,
			   uint32_t len, const void *src);

/*
 *
 * Debugging
 * ********************************************************
 *
 */

/**
 * Print packet to the console
 *
 * Print all packet debug information to the console.
 *
 * @param pkt  Packet handle
 */
void odp_packet_print(odp_packet_t pkt);

/**
 * Perform full packet validity check
 *
 * The operation may consume considerable number of cpu cycles depending on
 * the check level.
 *
 * @param pkt  Packet handle
 *
 * @retval 0 Packet is not valid
 * @retval 1 Packet is valid
 */
int odp_packet_is_valid(odp_packet_t pkt);


/**
 * @}
 */

#ifdef __cplusplus
}
#endif

#endif